diff --git a/clang/include/clang/AST/OpenMPClause.h b/clang/include/clang/AST/OpenMPClause.h
index 79f43fc8ab88..e82a5f09a32d 100644
--- a/clang/include/clang/AST/OpenMPClause.h
+++ b/clang/include/clang/AST/OpenMPClause.h
@@ -1,6993 +1,7015 @@
 //===- OpenMPClause.h - Classes for OpenMP clauses --------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 /// \file
 /// This file defines OpenMP AST classes for clauses.
 /// There are clauses for executable directives, clauses for declarative
 /// directives and clauses which can be used in both kinds of directives.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_AST_OPENMPCLAUSE_H
 #define LLVM_CLANG_AST_OPENMPCLAUSE_H
 
 #include "clang/AST/Decl.h"
 #include "clang/AST/DeclarationName.h"
 #include "clang/AST/Expr.h"
 #include "clang/AST/NestedNameSpecifier.h"
 #include "clang/AST/Stmt.h"
 #include "clang/AST/StmtIterator.h"
 #include "clang/Basic/LLVM.h"
 #include "clang/Basic/OpenMPKinds.h"
 #include "clang/Basic/SourceLocation.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/MapVector.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/iterator.h"
 #include "llvm/ADT/iterator_range.h"
 #include "llvm/Frontend/OpenMP/OMPConstants.h"
 #include "llvm/Frontend/OpenMP/OMPContext.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/TrailingObjects.h"
 #include <cassert>
 #include <cstddef>
 #include <iterator>
 #include <utility>
 
 namespace clang {
 
 class ASTContext;
 
 //===----------------------------------------------------------------------===//
 // AST classes for clauses.
 //===----------------------------------------------------------------------===//
 
 /// This is a basic class for representing single OpenMP clause.
 class OMPClause {
   /// Starting location of the clause (the clause keyword).
   SourceLocation StartLoc;
 
   /// Ending location of the clause.
   SourceLocation EndLoc;
 
   /// Kind of the clause.
   OpenMPClauseKind Kind;
 
 protected:
   OMPClause(OpenMPClauseKind K, SourceLocation StartLoc, SourceLocation EndLoc)
       : StartLoc(StartLoc), EndLoc(EndLoc), Kind(K) {}
 
 public:
   /// Returns the starting location of the clause.
   SourceLocation getBeginLoc() const { return StartLoc; }
 
   /// Returns the ending location of the clause.
   SourceLocation getEndLoc() const { return EndLoc; }
 
   /// Sets the starting location of the clause.
   void setLocStart(SourceLocation Loc) { StartLoc = Loc; }
 
   /// Sets the ending location of the clause.
   void setLocEnd(SourceLocation Loc) { EndLoc = Loc; }
 
   /// Returns kind of OpenMP clause (private, shared, reduction, etc.).
   OpenMPClauseKind getClauseKind() const { return Kind; }
 
   bool isImplicit() const { return StartLoc.isInvalid(); }
 
   using child_iterator = StmtIterator;
   using const_child_iterator = ConstStmtIterator;
   using child_range = llvm::iterator_range<child_iterator>;
   using const_child_range = llvm::iterator_range<const_child_iterator>;
 
   child_range children();
   const_child_range children() const {
     auto Children = const_cast<OMPClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   /// Get the iterator range for the expressions used in the clauses. Used
   /// expressions include only the children that must be evaluated at the
   /// runtime before entering the construct.
   child_range used_children();
   const_child_range used_children() const {
     auto Children = const_cast<OMPClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   static bool classof(const OMPClause *) { return true; }
 };
 
 /// Class that handles pre-initialization statement for some clauses, like
 /// 'shedule', 'firstprivate' etc.
 class OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Pre-initialization statement for the clause.
   Stmt *PreInit = nullptr;
 
   /// Region that captures the associated stmt.
   OpenMPDirectiveKind CaptureRegion = llvm::omp::OMPD_unknown;
 
 protected:
   OMPClauseWithPreInit(const OMPClause *This) {
     assert(get(This) && "get is not tuned for pre-init.");
   }
 
   /// Set pre-initialization statement for the clause.
   void
   setPreInitStmt(Stmt *S,
                  OpenMPDirectiveKind ThisRegion = llvm::omp::OMPD_unknown) {
     PreInit = S;
     CaptureRegion = ThisRegion;
   }
 
 public:
   /// Get pre-initialization statement for the clause.
   const Stmt *getPreInitStmt() const { return PreInit; }
 
   /// Get pre-initialization statement for the clause.
   Stmt *getPreInitStmt() { return PreInit; }
 
   /// Get capture region for the stmt in the clause.
   OpenMPDirectiveKind getCaptureRegion() const { return CaptureRegion; }
 
   static OMPClauseWithPreInit *get(OMPClause *C);
   static const OMPClauseWithPreInit *get(const OMPClause *C);
 };
 
 /// Class that handles post-update expression for some clauses, like
 /// 'lastprivate', 'reduction' etc.
 class OMPClauseWithPostUpdate : public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Post-update expression for the clause.
   Expr *PostUpdate = nullptr;
 
 protected:
   OMPClauseWithPostUpdate(const OMPClause *This) : OMPClauseWithPreInit(This) {
     assert(get(This) && "get is not tuned for post-update.");
   }
 
   /// Set pre-initialization statement for the clause.
   void setPostUpdateExpr(Expr *S) { PostUpdate = S; }
 
 public:
   /// Get post-update expression for the clause.
   const Expr *getPostUpdateExpr() const { return PostUpdate; }
 
   /// Get post-update expression for the clause.
   Expr *getPostUpdateExpr() { return PostUpdate; }
 
   static OMPClauseWithPostUpdate *get(OMPClause *C);
   static const OMPClauseWithPostUpdate *get(const OMPClause *C);
 };
 
 /// This structure contains most locations needed for by an OMPVarListClause.
 struct OMPVarListLocTy {
   /// Starting location of the clause (the clause keyword).
   SourceLocation StartLoc;
   /// Location of '('.
   SourceLocation LParenLoc;
   /// Ending location of the clause.
   SourceLocation EndLoc;
   OMPVarListLocTy() = default;
   OMPVarListLocTy(SourceLocation StartLoc, SourceLocation LParenLoc,
                   SourceLocation EndLoc)
       : StartLoc(StartLoc), LParenLoc(LParenLoc), EndLoc(EndLoc) {}
 };
 
 /// This represents clauses with the list of variables like 'private',
 /// 'firstprivate', 'copyin', 'shared', or 'reduction' clauses in the
 /// '#pragma omp ...' directives.
 template <class T> class OMPVarListClause : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Number of variables in the list.
   unsigned NumVars;
 
 protected:
   /// Build a clause with \a N variables
   ///
   /// \param K Kind of the clause.
   /// \param StartLoc Starting location of the clause (the clause keyword).
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param N Number of the variables in the clause.
   OMPVarListClause(OpenMPClauseKind K, SourceLocation StartLoc,
                    SourceLocation LParenLoc, SourceLocation EndLoc, unsigned N)
       : OMPClause(K, StartLoc, EndLoc), LParenLoc(LParenLoc), NumVars(N) {}
 
   /// Fetches list of variables associated with this clause.
   MutableArrayRef<Expr *> getVarRefs() {
     return MutableArrayRef<Expr *>(
         static_cast<T *>(this)->template getTrailingObjects<Expr *>(), NumVars);
   }
 
   /// Sets the list of variables for this clause.
   void setVarRefs(ArrayRef<Expr *> VL) {
     assert(VL.size() == NumVars &&
            "Number of variables is not the same as the preallocated buffer");
     std::copy(VL.begin(), VL.end(),
               static_cast<T *>(this)->template getTrailingObjects<Expr *>());
   }
 
 public:
   using varlist_iterator = MutableArrayRef<Expr *>::iterator;
   using varlist_const_iterator = ArrayRef<const Expr *>::iterator;
   using varlist_range = llvm::iterator_range<varlist_iterator>;
   using varlist_const_range = llvm::iterator_range<varlist_const_iterator>;
 
   unsigned varlist_size() const { return NumVars; }
   bool varlist_empty() const { return NumVars == 0; }
 
   varlist_range varlists() {
     return varlist_range(varlist_begin(), varlist_end());
   }
   varlist_const_range varlists() const {
     return varlist_const_range(varlist_begin(), varlist_end());
   }
 
   varlist_iterator varlist_begin() { return getVarRefs().begin(); }
   varlist_iterator varlist_end() { return getVarRefs().end(); }
   varlist_const_iterator varlist_begin() const { return getVarRefs().begin(); }
   varlist_const_iterator varlist_end() const { return getVarRefs().end(); }
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Fetches list of all variables in the clause.
   ArrayRef<const Expr *> getVarRefs() const {
     return llvm::makeArrayRef(
         static_cast<const T *>(this)->template getTrailingObjects<Expr *>(),
         NumVars);
   }
 };
 
 /// This represents 'allocator' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp allocate(a) allocator(omp_default_mem_alloc)
 /// \endcode
 /// In this example directive '#pragma omp allocate' has simple 'allocator'
 /// clause with the allocator 'omp_default_mem_alloc'.
 class OMPAllocatorClause : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Expression with the allocator.
   Stmt *Allocator = nullptr;
 
   /// Set allocator.
   void setAllocator(Expr *A) { Allocator = A; }
 
 public:
   /// Build 'allocator' clause with the given allocator.
   ///
   /// \param A Allocator.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPAllocatorClause(Expr *A, SourceLocation StartLoc, SourceLocation LParenLoc,
                      SourceLocation EndLoc)
       : OMPClause(OMPC_allocator, StartLoc, EndLoc), LParenLoc(LParenLoc),
         Allocator(A) {}
 
   /// Build an empty clause.
   OMPAllocatorClause()
       : OMPClause(OMPC_allocator, SourceLocation(), SourceLocation()) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Returns allocator.
   Expr *getAllocator() const { return cast_or_null<Expr>(Allocator); }
 
   child_range children() { return child_range(&Allocator, &Allocator + 1); }
 
   const_child_range children() const {
     return const_child_range(&Allocator, &Allocator + 1);
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_allocator;
   }
 };
 
 /// This represents clause 'allocate' in the '#pragma omp ...' directives.
 ///
 /// \code
 /// #pragma omp parallel private(a) allocate(omp_default_mem_alloc :a)
 /// \endcode
 /// In this example directive '#pragma omp parallel' has clause 'private'
 /// and clause 'allocate' for the variable 'a'.
 class OMPAllocateClause final
     : public OMPVarListClause<OMPAllocateClause>,
       private llvm::TrailingObjects<OMPAllocateClause, Expr *> {
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Allocator specified in the clause, or 'nullptr' if the default one is
   /// used.
   Expr *Allocator = nullptr;
   /// Position of the ':' delimiter in the clause;
   SourceLocation ColonLoc;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param Allocator Allocator expression.
   /// \param ColonLoc Location of ':' delimiter.
   /// \param EndLoc Ending location of the clause.
   /// \param N Number of the variables in the clause.
   OMPAllocateClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                     Expr *Allocator, SourceLocation ColonLoc,
                     SourceLocation EndLoc, unsigned N)
       : OMPVarListClause<OMPAllocateClause>(OMPC_allocate, StartLoc, LParenLoc,
                                             EndLoc, N),
         Allocator(Allocator), ColonLoc(ColonLoc) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPAllocateClause(unsigned N)
       : OMPVarListClause<OMPAllocateClause>(OMPC_allocate, SourceLocation(),
                                             SourceLocation(), SourceLocation(),
                                             N) {}
 
   /// Sets location of ':' symbol in clause.
   void setColonLoc(SourceLocation CL) { ColonLoc = CL; }
 
   void setAllocator(Expr *A) { Allocator = A; }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param Allocator Allocator expression.
   /// \param ColonLoc Location of ':' delimiter.
   /// \param EndLoc Ending location of the clause.
   /// \param VL List of references to the variables.
   static OMPAllocateClause *Create(const ASTContext &C, SourceLocation StartLoc,
                                    SourceLocation LParenLoc, Expr *Allocator,
                                    SourceLocation ColonLoc,
                                    SourceLocation EndLoc, ArrayRef<Expr *> VL);
 
   /// Returns the allocator expression or nullptr, if no allocator is specified.
   Expr *getAllocator() const { return Allocator; }
 
   /// Returns the location of the ':' delimiter.
   SourceLocation getColonLoc() const { return ColonLoc; }
 
   /// Creates an empty clause with the place for \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPAllocateClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPAllocateClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_allocate;
   }
 };
 
 /// This represents 'if' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp parallel if(parallel:a > 5)
 /// \endcode
 /// In this example directive '#pragma omp parallel' has simple 'if' clause with
 /// condition 'a > 5' and directive name modifier 'parallel'.
 class OMPIfClause : public OMPClause, public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Condition of the 'if' clause.
   Stmt *Condition = nullptr;
 
   /// Location of ':' (if any).
   SourceLocation ColonLoc;
 
   /// Directive name modifier for the clause.
   OpenMPDirectiveKind NameModifier = llvm::omp::OMPD_unknown;
 
   /// Name modifier location.
   SourceLocation NameModifierLoc;
 
   /// Set condition.
   void setCondition(Expr *Cond) { Condition = Cond; }
 
   /// Set directive name modifier for the clause.
   void setNameModifier(OpenMPDirectiveKind NM) { NameModifier = NM; }
 
   /// Set location of directive name modifier for the clause.
   void setNameModifierLoc(SourceLocation Loc) { NameModifierLoc = Loc; }
 
   /// Set location of ':'.
   void setColonLoc(SourceLocation Loc) { ColonLoc = Loc; }
 
 public:
   /// Build 'if' clause with condition \a Cond.
   ///
   /// \param NameModifier [OpenMP 4.1] Directive name modifier of clause.
   /// \param Cond Condition of the clause.
   /// \param HelperCond Helper condition for the clause.
   /// \param CaptureRegion Innermost OpenMP region where expressions in this
   /// clause must be captured.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param NameModifierLoc Location of directive name modifier.
   /// \param ColonLoc [OpenMP 4.1] Location of ':'.
   /// \param EndLoc Ending location of the clause.
   OMPIfClause(OpenMPDirectiveKind NameModifier, Expr *Cond, Stmt *HelperCond,
               OpenMPDirectiveKind CaptureRegion, SourceLocation StartLoc,
               SourceLocation LParenLoc, SourceLocation NameModifierLoc,
               SourceLocation ColonLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_if, StartLoc, EndLoc), OMPClauseWithPreInit(this),
         LParenLoc(LParenLoc), Condition(Cond), ColonLoc(ColonLoc),
         NameModifier(NameModifier), NameModifierLoc(NameModifierLoc) {
     setPreInitStmt(HelperCond, CaptureRegion);
   }
 
   /// Build an empty clause.
   OMPIfClause()
       : OMPClause(OMPC_if, SourceLocation(), SourceLocation()),
         OMPClauseWithPreInit(this) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Return the location of ':'.
   SourceLocation getColonLoc() const { return ColonLoc; }
 
   /// Returns condition.
   Expr *getCondition() const { return cast_or_null<Expr>(Condition); }
 
   /// Return directive name modifier associated with the clause.
   OpenMPDirectiveKind getNameModifier() const { return NameModifier; }
 
   /// Return the location of directive name modifier.
   SourceLocation getNameModifierLoc() const { return NameModifierLoc; }
 
   child_range children() { return child_range(&Condition, &Condition + 1); }
 
   const_child_range children() const {
     return const_child_range(&Condition, &Condition + 1);
   }
 
   child_range used_children();
   const_child_range used_children() const {
     auto Children = const_cast<OMPIfClause *>(this)->used_children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_if;
   }
 };
 
 /// This represents 'final' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp task final(a > 5)
 /// \endcode
 /// In this example directive '#pragma omp task' has simple 'final'
 /// clause with condition 'a > 5'.
 class OMPFinalClause : public OMPClause, public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Condition of the 'if' clause.
   Stmt *Condition = nullptr;
 
   /// Set condition.
   void setCondition(Expr *Cond) { Condition = Cond; }
 
 public:
   /// Build 'final' clause with condition \a Cond.
   ///
   /// \param Cond Condition of the clause.
   /// \param HelperCond Helper condition for the construct.
   /// \param CaptureRegion Innermost OpenMP region where expressions in this
   /// clause must be captured.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPFinalClause(Expr *Cond, Stmt *HelperCond,
                  OpenMPDirectiveKind CaptureRegion, SourceLocation StartLoc,
                  SourceLocation LParenLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_final, StartLoc, EndLoc), OMPClauseWithPreInit(this),
         LParenLoc(LParenLoc), Condition(Cond) {
     setPreInitStmt(HelperCond, CaptureRegion);
   }
 
   /// Build an empty clause.
   OMPFinalClause()
       : OMPClause(OMPC_final, SourceLocation(), SourceLocation()),
         OMPClauseWithPreInit(this) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Returns condition.
   Expr *getCondition() const { return cast_or_null<Expr>(Condition); }
 
   child_range children() { return child_range(&Condition, &Condition + 1); }
 
   const_child_range children() const {
     return const_child_range(&Condition, &Condition + 1);
   }
 
   child_range used_children();
   const_child_range used_children() const {
     auto Children = const_cast<OMPFinalClause *>(this)->used_children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_final;
   }
 };
 
 /// This represents 'num_threads' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp parallel num_threads(6)
 /// \endcode
 /// In this example directive '#pragma omp parallel' has simple 'num_threads'
 /// clause with number of threads '6'.
 class OMPNumThreadsClause : public OMPClause, public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Condition of the 'num_threads' clause.
   Stmt *NumThreads = nullptr;
 
   /// Set condition.
   void setNumThreads(Expr *NThreads) { NumThreads = NThreads; }
 
 public:
   /// Build 'num_threads' clause with condition \a NumThreads.
   ///
   /// \param NumThreads Number of threads for the construct.
   /// \param HelperNumThreads Helper Number of threads for the construct.
   /// \param CaptureRegion Innermost OpenMP region where expressions in this
   /// clause must be captured.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPNumThreadsClause(Expr *NumThreads, Stmt *HelperNumThreads,
                       OpenMPDirectiveKind CaptureRegion,
                       SourceLocation StartLoc, SourceLocation LParenLoc,
                       SourceLocation EndLoc)
       : OMPClause(OMPC_num_threads, StartLoc, EndLoc),
         OMPClauseWithPreInit(this), LParenLoc(LParenLoc),
         NumThreads(NumThreads) {
     setPreInitStmt(HelperNumThreads, CaptureRegion);
   }
 
   /// Build an empty clause.
   OMPNumThreadsClause()
       : OMPClause(OMPC_num_threads, SourceLocation(), SourceLocation()),
         OMPClauseWithPreInit(this) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Returns number of threads.
   Expr *getNumThreads() const { return cast_or_null<Expr>(NumThreads); }
 
   child_range children() { return child_range(&NumThreads, &NumThreads + 1); }
 
   const_child_range children() const {
     return const_child_range(&NumThreads, &NumThreads + 1);
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_num_threads;
   }
 };
 
 /// This represents 'safelen' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp simd safelen(4)
 /// \endcode
 /// In this example directive '#pragma omp simd' has clause 'safelen'
 /// with single expression '4'.
 /// If the safelen clause is used then no two iterations executed
 /// concurrently with SIMD instructions can have a greater distance
 /// in the logical iteration space than its value. The parameter of
 /// the safelen clause must be a constant positive integer expression.
 class OMPSafelenClause : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Safe iteration space distance.
   Stmt *Safelen = nullptr;
 
   /// Set safelen.
   void setSafelen(Expr *Len) { Safelen = Len; }
 
 public:
   /// Build 'safelen' clause.
   ///
   /// \param Len Expression associated with this clause.
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPSafelenClause(Expr *Len, SourceLocation StartLoc, SourceLocation LParenLoc,
                    SourceLocation EndLoc)
       : OMPClause(OMPC_safelen, StartLoc, EndLoc), LParenLoc(LParenLoc),
         Safelen(Len) {}
 
   /// Build an empty clause.
   explicit OMPSafelenClause()
       : OMPClause(OMPC_safelen, SourceLocation(), SourceLocation()) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Return safe iteration space distance.
   Expr *getSafelen() const { return cast_or_null<Expr>(Safelen); }
 
   child_range children() { return child_range(&Safelen, &Safelen + 1); }
 
   const_child_range children() const {
     return const_child_range(&Safelen, &Safelen + 1);
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_safelen;
   }
 };
 
 /// This represents 'simdlen' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp simd simdlen(4)
 /// \endcode
 /// In this example directive '#pragma omp simd' has clause 'simdlen'
 /// with single expression '4'.
 /// If the 'simdlen' clause is used then it specifies the preferred number of
 /// iterations to be executed concurrently. The parameter of the 'simdlen'
 /// clause must be a constant positive integer expression.
 class OMPSimdlenClause : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Safe iteration space distance.
   Stmt *Simdlen = nullptr;
 
   /// Set simdlen.
   void setSimdlen(Expr *Len) { Simdlen = Len; }
 
 public:
   /// Build 'simdlen' clause.
   ///
   /// \param Len Expression associated with this clause.
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPSimdlenClause(Expr *Len, SourceLocation StartLoc, SourceLocation LParenLoc,
                    SourceLocation EndLoc)
       : OMPClause(OMPC_simdlen, StartLoc, EndLoc), LParenLoc(LParenLoc),
         Simdlen(Len) {}
 
   /// Build an empty clause.
   explicit OMPSimdlenClause()
       : OMPClause(OMPC_simdlen, SourceLocation(), SourceLocation()) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Return safe iteration space distance.
   Expr *getSimdlen() const { return cast_or_null<Expr>(Simdlen); }
 
   child_range children() { return child_range(&Simdlen, &Simdlen + 1); }
 
   const_child_range children() const {
     return const_child_range(&Simdlen, &Simdlen + 1);
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_simdlen;
   }
 };
 
 /// This represents 'collapse' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp simd collapse(3)
 /// \endcode
 /// In this example directive '#pragma omp simd' has clause 'collapse'
 /// with single expression '3'.
 /// The parameter must be a constant positive integer expression, it specifies
 /// the number of nested loops that should be collapsed into a single iteration
 /// space.
 class OMPCollapseClause : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Number of for-loops.
   Stmt *NumForLoops = nullptr;
 
   /// Set the number of associated for-loops.
   void setNumForLoops(Expr *Num) { NumForLoops = Num; }
 
 public:
   /// Build 'collapse' clause.
   ///
   /// \param Num Expression associated with this clause.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPCollapseClause(Expr *Num, SourceLocation StartLoc,
                     SourceLocation LParenLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_collapse, StartLoc, EndLoc), LParenLoc(LParenLoc),
         NumForLoops(Num) {}
 
   /// Build an empty clause.
   explicit OMPCollapseClause()
       : OMPClause(OMPC_collapse, SourceLocation(), SourceLocation()) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Return the number of associated for-loops.
   Expr *getNumForLoops() const { return cast_or_null<Expr>(NumForLoops); }
 
   child_range children() { return child_range(&NumForLoops, &NumForLoops + 1); }
 
   const_child_range children() const {
     return const_child_range(&NumForLoops, &NumForLoops + 1);
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_collapse;
   }
 };
 
 /// This represents 'default' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp parallel default(shared)
 /// \endcode
 /// In this example directive '#pragma omp parallel' has simple 'default'
 /// clause with kind 'shared'.
 class OMPDefaultClause : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// A kind of the 'default' clause.
   llvm::omp::DefaultKind Kind = llvm::omp::OMP_DEFAULT_unknown;
 
   /// Start location of the kind in source code.
   SourceLocation KindKwLoc;
 
   /// Set kind of the clauses.
   ///
   /// \param K Argument of clause.
   void setDefaultKind(llvm::omp::DefaultKind K) { Kind = K; }
 
   /// Set argument location.
   ///
   /// \param KLoc Argument location.
   void setDefaultKindKwLoc(SourceLocation KLoc) { KindKwLoc = KLoc; }
 
 public:
   /// Build 'default' clause with argument \a A ('none' or 'shared').
   ///
   /// \param A Argument of the clause ('none' or 'shared').
   /// \param ALoc Starting location of the argument.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPDefaultClause(llvm::omp::DefaultKind A, SourceLocation ALoc,
                    SourceLocation StartLoc, SourceLocation LParenLoc,
                    SourceLocation EndLoc)
       : OMPClause(OMPC_default, StartLoc, EndLoc), LParenLoc(LParenLoc),
         Kind(A), KindKwLoc(ALoc) {}
 
   /// Build an empty clause.
   OMPDefaultClause()
       : OMPClause(OMPC_default, SourceLocation(), SourceLocation()) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Returns kind of the clause.
   llvm::omp::DefaultKind getDefaultKind() const { return Kind; }
 
   /// Returns location of clause kind.
   SourceLocation getDefaultKindKwLoc() const { return KindKwLoc; }
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_default;
   }
 };
 
 /// This represents 'proc_bind' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp parallel proc_bind(master)
 /// \endcode
 /// In this example directive '#pragma omp parallel' has simple 'proc_bind'
 /// clause with kind 'master'.
 class OMPProcBindClause : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// A kind of the 'proc_bind' clause.
   llvm::omp::ProcBindKind Kind = llvm::omp::OMP_PROC_BIND_unknown;
 
   /// Start location of the kind in source code.
   SourceLocation KindKwLoc;
 
   /// Set kind of the clause.
   ///
   /// \param K Kind of clause.
   void setProcBindKind(llvm::omp::ProcBindKind K) { Kind = K; }
 
   /// Set clause kind location.
   ///
   /// \param KLoc Kind location.
   void setProcBindKindKwLoc(SourceLocation KLoc) { KindKwLoc = KLoc; }
 
 public:
   /// Build 'proc_bind' clause with argument \a A ('master', 'close' or
   ///        'spread').
   ///
   /// \param A Argument of the clause ('master', 'close' or 'spread').
   /// \param ALoc Starting location of the argument.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPProcBindClause(llvm::omp::ProcBindKind A, SourceLocation ALoc,
                     SourceLocation StartLoc, SourceLocation LParenLoc,
                     SourceLocation EndLoc)
       : OMPClause(OMPC_proc_bind, StartLoc, EndLoc), LParenLoc(LParenLoc),
         Kind(A), KindKwLoc(ALoc) {}
 
   /// Build an empty clause.
   OMPProcBindClause()
       : OMPClause(OMPC_proc_bind, SourceLocation(), SourceLocation()) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Returns kind of the clause.
   llvm::omp::ProcBindKind getProcBindKind() const { return Kind; }
 
   /// Returns location of clause kind.
   SourceLocation getProcBindKindKwLoc() const { return KindKwLoc; }
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_proc_bind;
   }
 };
 
 /// This represents 'unified_address' clause in the '#pragma omp requires'
 /// directive.
 ///
 /// \code
 /// #pragma omp requires unified_address
 /// \endcode
 /// In this example directive '#pragma omp requires' has 'unified_address'
 /// clause.
 class OMPUnifiedAddressClause final : public OMPClause {
 public:
   friend class OMPClauseReader;
   /// Build 'unified_address' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPUnifiedAddressClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_unified_address, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPUnifiedAddressClause()
       : OMPClause(OMPC_unified_address, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_unified_address;
   }
 };
 
 /// This represents 'unified_shared_memory' clause in the '#pragma omp requires'
 /// directive.
 ///
 /// \code
 /// #pragma omp requires unified_shared_memory
 /// \endcode
 /// In this example directive '#pragma omp requires' has 'unified_shared_memory'
 /// clause.
 class OMPUnifiedSharedMemoryClause final : public OMPClause {
 public:
   friend class OMPClauseReader;
   /// Build 'unified_shared_memory' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPUnifiedSharedMemoryClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_unified_shared_memory, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPUnifiedSharedMemoryClause()
       : OMPClause(OMPC_unified_shared_memory, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_unified_shared_memory;
   }
 };
 
 /// This represents 'reverse_offload' clause in the '#pragma omp requires'
 /// directive.
 ///
 /// \code
 /// #pragma omp requires reverse_offload
 /// \endcode
 /// In this example directive '#pragma omp requires' has 'reverse_offload'
 /// clause.
 class OMPReverseOffloadClause final : public OMPClause {
 public:
   friend class OMPClauseReader;
   /// Build 'reverse_offload' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPReverseOffloadClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_reverse_offload, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPReverseOffloadClause()
       : OMPClause(OMPC_reverse_offload, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_reverse_offload;
   }
 };
 
 /// This represents 'dynamic_allocators' clause in the '#pragma omp requires'
 /// directive.
 ///
 /// \code
 /// #pragma omp requires dynamic_allocators
 /// \endcode
 /// In this example directive '#pragma omp requires' has 'dynamic_allocators'
 /// clause.
 class OMPDynamicAllocatorsClause final : public OMPClause {
 public:
   friend class OMPClauseReader;
   /// Build 'dynamic_allocators' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPDynamicAllocatorsClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_dynamic_allocators, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPDynamicAllocatorsClause()
       : OMPClause(OMPC_dynamic_allocators, SourceLocation(), SourceLocation()) {
   }
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_dynamic_allocators;
   }
 };
 
 /// This represents 'atomic_default_mem_order' clause in the '#pragma omp
 /// requires'  directive.
 ///
 /// \code
 /// #pragma omp requires atomic_default_mem_order(seq_cst)
 /// \endcode
 /// In this example directive '#pragma omp requires' has simple
 /// atomic_default_mem_order' clause with kind 'seq_cst'.
 class OMPAtomicDefaultMemOrderClause final : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('
   SourceLocation LParenLoc;
 
   /// A kind of the 'atomic_default_mem_order' clause.
   OpenMPAtomicDefaultMemOrderClauseKind Kind =
       OMPC_ATOMIC_DEFAULT_MEM_ORDER_unknown;
 
   /// Start location of the kind in source code.
   SourceLocation KindKwLoc;
 
   /// Set kind of the clause.
   ///
   /// \param K Kind of clause.
   void setAtomicDefaultMemOrderKind(OpenMPAtomicDefaultMemOrderClauseKind K) {
     Kind = K;
   }
 
   /// Set clause kind location.
   ///
   /// \param KLoc Kind location.
   void setAtomicDefaultMemOrderKindKwLoc(SourceLocation KLoc) {
     KindKwLoc = KLoc;
   }
 
 public:
   /// Build 'atomic_default_mem_order' clause with argument \a A ('seq_cst',
   /// 'acq_rel' or 'relaxed').
   ///
   /// \param A Argument of the clause ('seq_cst', 'acq_rel' or 'relaxed').
   /// \param ALoc Starting location of the argument.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPAtomicDefaultMemOrderClause(OpenMPAtomicDefaultMemOrderClauseKind A,
                                  SourceLocation ALoc, SourceLocation StartLoc,
                                  SourceLocation LParenLoc,
                                  SourceLocation EndLoc)
       : OMPClause(OMPC_atomic_default_mem_order, StartLoc, EndLoc),
         LParenLoc(LParenLoc), Kind(A), KindKwLoc(ALoc) {}
 
   /// Build an empty clause.
   OMPAtomicDefaultMemOrderClause()
       : OMPClause(OMPC_atomic_default_mem_order, SourceLocation(),
                   SourceLocation()) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the locaiton of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Returns kind of the clause.
   OpenMPAtomicDefaultMemOrderClauseKind getAtomicDefaultMemOrderKind() const {
     return Kind;
   }
 
   /// Returns location of clause kind.
   SourceLocation getAtomicDefaultMemOrderKindKwLoc() const { return KindKwLoc; }
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_atomic_default_mem_order;
   }
 };
 
 /// This represents 'schedule' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp for schedule(static, 3)
 /// \endcode
 /// In this example directive '#pragma omp for' has 'schedule' clause with
 /// arguments 'static' and '3'.
 class OMPScheduleClause : public OMPClause, public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// A kind of the 'schedule' clause.
   OpenMPScheduleClauseKind Kind = OMPC_SCHEDULE_unknown;
 
   /// Modifiers for 'schedule' clause.
   enum {FIRST, SECOND, NUM_MODIFIERS};
   OpenMPScheduleClauseModifier Modifiers[NUM_MODIFIERS];
 
   /// Locations of modifiers.
   SourceLocation ModifiersLoc[NUM_MODIFIERS];
 
   /// Start location of the schedule ind in source code.
   SourceLocation KindLoc;
 
   /// Location of ',' (if any).
   SourceLocation CommaLoc;
 
   /// Chunk size.
   Expr *ChunkSize = nullptr;
 
   /// Set schedule kind.
   ///
   /// \param K Schedule kind.
   void setScheduleKind(OpenMPScheduleClauseKind K) { Kind = K; }
 
   /// Set the first schedule modifier.
   ///
   /// \param M Schedule modifier.
   void setFirstScheduleModifier(OpenMPScheduleClauseModifier M) {
     Modifiers[FIRST] = M;
   }
 
   /// Set the second schedule modifier.
   ///
   /// \param M Schedule modifier.
   void setSecondScheduleModifier(OpenMPScheduleClauseModifier M) {
     Modifiers[SECOND] = M;
   }
 
   /// Set location of the first schedule modifier.
   void setFirstScheduleModifierLoc(SourceLocation Loc) {
     ModifiersLoc[FIRST] = Loc;
   }
 
   /// Set location of the second schedule modifier.
   void setSecondScheduleModifierLoc(SourceLocation Loc) {
     ModifiersLoc[SECOND] = Loc;
   }
 
   /// Set schedule modifier location.
   ///
   /// \param M Schedule modifier location.
   void setScheduleModifer(OpenMPScheduleClauseModifier M) {
     if (Modifiers[FIRST] == OMPC_SCHEDULE_MODIFIER_unknown)
       Modifiers[FIRST] = M;
     else {
       assert(Modifiers[SECOND] == OMPC_SCHEDULE_MODIFIER_unknown);
       Modifiers[SECOND] = M;
     }
   }
 
   /// Sets the location of '('.
   ///
   /// \param Loc Location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Set schedule kind start location.
   ///
   /// \param KLoc Schedule kind location.
   void setScheduleKindLoc(SourceLocation KLoc) { KindLoc = KLoc; }
 
   /// Set location of ','.
   ///
   /// \param Loc Location of ','.
   void setCommaLoc(SourceLocation Loc) { CommaLoc = Loc; }
 
   /// Set chunk size.
   ///
   /// \param E Chunk size.
   void setChunkSize(Expr *E) { ChunkSize = E; }
 
 public:
   /// Build 'schedule' clause with schedule kind \a Kind and chunk size
   /// expression \a ChunkSize.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param KLoc Starting location of the argument.
   /// \param CommaLoc Location of ','.
   /// \param EndLoc Ending location of the clause.
   /// \param Kind Schedule kind.
   /// \param ChunkSize Chunk size.
   /// \param HelperChunkSize Helper chunk size for combined directives.
   /// \param M1 The first modifier applied to 'schedule' clause.
   /// \param M1Loc Location of the first modifier
   /// \param M2 The second modifier applied to 'schedule' clause.
   /// \param M2Loc Location of the second modifier
   OMPScheduleClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                     SourceLocation KLoc, SourceLocation CommaLoc,
                     SourceLocation EndLoc, OpenMPScheduleClauseKind Kind,
                     Expr *ChunkSize, Stmt *HelperChunkSize,
                     OpenMPScheduleClauseModifier M1, SourceLocation M1Loc,
                     OpenMPScheduleClauseModifier M2, SourceLocation M2Loc)
       : OMPClause(OMPC_schedule, StartLoc, EndLoc), OMPClauseWithPreInit(this),
         LParenLoc(LParenLoc), Kind(Kind), KindLoc(KLoc), CommaLoc(CommaLoc),
         ChunkSize(ChunkSize) {
     setPreInitStmt(HelperChunkSize);
     Modifiers[FIRST] = M1;
     Modifiers[SECOND] = M2;
     ModifiersLoc[FIRST] = M1Loc;
     ModifiersLoc[SECOND] = M2Loc;
   }
 
   /// Build an empty clause.
   explicit OMPScheduleClause()
       : OMPClause(OMPC_schedule, SourceLocation(), SourceLocation()),
         OMPClauseWithPreInit(this) {
     Modifiers[FIRST] = OMPC_SCHEDULE_MODIFIER_unknown;
     Modifiers[SECOND] = OMPC_SCHEDULE_MODIFIER_unknown;
   }
 
   /// Get kind of the clause.
   OpenMPScheduleClauseKind getScheduleKind() const { return Kind; }
 
   /// Get the first modifier of the clause.
   OpenMPScheduleClauseModifier getFirstScheduleModifier() const {
     return Modifiers[FIRST];
   }
 
   /// Get the second modifier of the clause.
   OpenMPScheduleClauseModifier getSecondScheduleModifier() const {
     return Modifiers[SECOND];
   }
 
   /// Get location of '('.
   SourceLocation getLParenLoc() { return LParenLoc; }
 
   /// Get kind location.
   SourceLocation getScheduleKindLoc() { return KindLoc; }
 
   /// Get the first modifier location.
   SourceLocation getFirstScheduleModifierLoc() const {
     return ModifiersLoc[FIRST];
   }
 
   /// Get the second modifier location.
   SourceLocation getSecondScheduleModifierLoc() const {
     return ModifiersLoc[SECOND];
   }
 
   /// Get location of ','.
   SourceLocation getCommaLoc() { return CommaLoc; }
 
   /// Get chunk size.
   Expr *getChunkSize() { return ChunkSize; }
 
   /// Get chunk size.
   const Expr *getChunkSize() const { return ChunkSize; }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(&ChunkSize),
                        reinterpret_cast<Stmt **>(&ChunkSize) + 1);
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPScheduleClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_schedule;
   }
 };
 
 /// This represents 'ordered' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp for ordered (2)
 /// \endcode
 /// In this example directive '#pragma omp for' has 'ordered' clause with
 /// parameter 2.
 class OMPOrderedClause final
     : public OMPClause,
       private llvm::TrailingObjects<OMPOrderedClause, Expr *> {
   friend class OMPClauseReader;
   friend TrailingObjects;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Number of for-loops.
   Stmt *NumForLoops = nullptr;
 
   /// Real number of loops.
   unsigned NumberOfLoops = 0;
 
   /// Build 'ordered' clause.
   ///
   /// \param Num Expression, possibly associated with this clause.
   /// \param NumLoops Number of loops, associated with this clause.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPOrderedClause(Expr *Num, unsigned NumLoops, SourceLocation StartLoc,
                    SourceLocation LParenLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_ordered, StartLoc, EndLoc), LParenLoc(LParenLoc),
         NumForLoops(Num), NumberOfLoops(NumLoops) {}
 
   /// Build an empty clause.
   explicit OMPOrderedClause(unsigned NumLoops)
       : OMPClause(OMPC_ordered, SourceLocation(), SourceLocation()),
         NumberOfLoops(NumLoops) {}
 
   /// Set the number of associated for-loops.
   void setNumForLoops(Expr *Num) { NumForLoops = Num; }
 
 public:
   /// Build 'ordered' clause.
   ///
   /// \param Num Expression, possibly associated with this clause.
   /// \param NumLoops Number of loops, associated with this clause.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   static OMPOrderedClause *Create(const ASTContext &C, Expr *Num,
                                   unsigned NumLoops, SourceLocation StartLoc,
                                   SourceLocation LParenLoc,
                                   SourceLocation EndLoc);
 
   /// Build an empty clause.
   static OMPOrderedClause* CreateEmpty(const ASTContext &C, unsigned NumLoops);
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Return the number of associated for-loops.
   Expr *getNumForLoops() const { return cast_or_null<Expr>(NumForLoops); }
 
   /// Set number of iterations for the specified loop.
   void setLoopNumIterations(unsigned NumLoop, Expr *NumIterations);
   /// Get number of iterations for all the loops.
   ArrayRef<Expr *> getLoopNumIterations() const;
 
   /// Set loop counter for the specified loop.
   void setLoopCounter(unsigned NumLoop, Expr *Counter);
   /// Get loops counter for the specified loop.
   Expr *getLoopCounter(unsigned NumLoop);
   const Expr *getLoopCounter(unsigned NumLoop) const;
 
   child_range children() { return child_range(&NumForLoops, &NumForLoops + 1); }
 
   const_child_range children() const {
     return const_child_range(&NumForLoops, &NumForLoops + 1);
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_ordered;
   }
 };
 
 /// This represents 'nowait' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp for nowait
 /// \endcode
 /// In this example directive '#pragma omp for' has 'nowait' clause.
 class OMPNowaitClause : public OMPClause {
 public:
   /// Build 'nowait' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPNowaitClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_nowait, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPNowaitClause()
       : OMPClause(OMPC_nowait, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_nowait;
   }
 };
 
 /// This represents 'untied' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp task untied
 /// \endcode
 /// In this example directive '#pragma omp task' has 'untied' clause.
 class OMPUntiedClause : public OMPClause {
 public:
   /// Build 'untied' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPUntiedClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_untied, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPUntiedClause()
       : OMPClause(OMPC_untied, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_untied;
   }
 };
 
 /// This represents 'mergeable' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp task mergeable
 /// \endcode
 /// In this example directive '#pragma omp task' has 'mergeable' clause.
 class OMPMergeableClause : public OMPClause {
 public:
   /// Build 'mergeable' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPMergeableClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_mergeable, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPMergeableClause()
       : OMPClause(OMPC_mergeable, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_mergeable;
   }
 };
 
 /// This represents 'read' clause in the '#pragma omp atomic' directive.
 ///
 /// \code
 /// #pragma omp atomic read
 /// \endcode
 /// In this example directive '#pragma omp atomic' has 'read' clause.
 class OMPReadClause : public OMPClause {
 public:
   /// Build 'read' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPReadClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_read, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPReadClause() : OMPClause(OMPC_read, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_read;
   }
 };
 
 /// This represents 'write' clause in the '#pragma omp atomic' directive.
 ///
 /// \code
 /// #pragma omp atomic write
 /// \endcode
 /// In this example directive '#pragma omp atomic' has 'write' clause.
 class OMPWriteClause : public OMPClause {
 public:
   /// Build 'write' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPWriteClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_write, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPWriteClause()
       : OMPClause(OMPC_write, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_write;
   }
 };
 
 /// This represents 'update' clause in the '#pragma omp atomic'
 /// directive.
 ///
 /// \code
 /// #pragma omp atomic update
 /// \endcode
 /// In this example directive '#pragma omp atomic' has 'update' clause.
 /// Also, this class represents 'update' clause in  '#pragma omp depobj'
 /// directive.
 ///
 /// \code
 /// #pragma omp depobj(a) update(in)
 /// \endcode
 /// In this example directive '#pragma omp depobj' has 'update' clause with 'in'
 /// dependence kind.
 class OMPUpdateClause final
     : public OMPClause,
       private llvm::TrailingObjects<OMPUpdateClause, SourceLocation,
                                     OpenMPDependClauseKind> {
   friend class OMPClauseReader;
   friend TrailingObjects;
 
   /// true if extended version of the clause for 'depobj' directive.
   bool IsExtended = false;
 
   /// Define the sizes of each trailing object array except the last one. This
   /// is required for TrailingObjects to work properly.
   size_t numTrailingObjects(OverloadToken<SourceLocation>) const {
     // 2 locations: for '(' and argument location.
     return IsExtended ? 2 : 0;
   }
 
   /// Sets the the location of '(' in clause for 'depobj' directive.
   void setLParenLoc(SourceLocation Loc) {
     assert(IsExtended && "Expected extended clause.");
     *getTrailingObjects<SourceLocation>() = Loc;
   }
 
   /// Sets the the location of '(' in clause for 'depobj' directive.
   void setArgumentLoc(SourceLocation Loc) {
     assert(IsExtended && "Expected extended clause.");
     *std::next(getTrailingObjects<SourceLocation>(), 1) = Loc;
   }
 
   /// Sets the dependence kind for the clause for 'depobj' directive.
   void setDependencyKind(OpenMPDependClauseKind DK) {
     assert(IsExtended && "Expected extended clause.");
     *getTrailingObjects<OpenMPDependClauseKind>() = DK;
   }
 
   /// Build 'update' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPUpdateClause(SourceLocation StartLoc, SourceLocation EndLoc,
                   bool IsExtended)
       : OMPClause(OMPC_update, StartLoc, EndLoc), IsExtended(IsExtended) {}
 
   /// Build an empty clause.
   OMPUpdateClause(bool IsExtended)
       : OMPClause(OMPC_update, SourceLocation(), SourceLocation()),
         IsExtended(IsExtended) {}
 
 public:
   /// Creates clause for 'atomic' directive.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   static OMPUpdateClause *Create(const ASTContext &C, SourceLocation StartLoc,
                                  SourceLocation EndLoc);
 
   /// Creates clause for 'depobj' directive.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param ArgumentLoc Location of the argument.
   /// \param DK Dependence kind.
   /// \param EndLoc Ending location of the clause.
   static OMPUpdateClause *Create(const ASTContext &C, SourceLocation StartLoc,
                                  SourceLocation LParenLoc,
                                  SourceLocation ArgumentLoc,
                                  OpenMPDependClauseKind DK,
                                  SourceLocation EndLoc);
 
   /// Creates an empty clause with the place for \a N variables.
   ///
   /// \param C AST context.
   /// \param IsExtended true if extended clause for 'depobj' directive must be
   /// created.
   static OMPUpdateClause *CreateEmpty(const ASTContext &C, bool IsExtended);
 
   /// Checks if the clause is the extended clauses for 'depobj' directive.
   bool isExtended() const { return IsExtended; }
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   /// Gets the the location of '(' in clause for 'depobj' directive.
   SourceLocation getLParenLoc() const {
     assert(IsExtended && "Expected extended clause.");
     return *getTrailingObjects<SourceLocation>();
   }
 
   /// Gets the the location of argument in clause for 'depobj' directive.
   SourceLocation getArgumentLoc() const {
     assert(IsExtended && "Expected extended clause.");
     return *std::next(getTrailingObjects<SourceLocation>(), 1);
   }
 
   /// Gets the dependence kind in clause for 'depobj' directive.
   OpenMPDependClauseKind getDependencyKind() const {
     assert(IsExtended && "Expected extended clause.");
     return *getTrailingObjects<OpenMPDependClauseKind>();
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_update;
   }
 };
 
 /// This represents 'capture' clause in the '#pragma omp atomic'
 /// directive.
 ///
 /// \code
 /// #pragma omp atomic capture
 /// \endcode
 /// In this example directive '#pragma omp atomic' has 'capture' clause.
 class OMPCaptureClause : public OMPClause {
 public:
   /// Build 'capture' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPCaptureClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_capture, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPCaptureClause()
       : OMPClause(OMPC_capture, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_capture;
   }
 };
 
 /// This represents 'seq_cst' clause in the '#pragma omp atomic'
 /// directive.
 ///
 /// \code
 /// #pragma omp atomic seq_cst
 /// \endcode
 /// In this example directive '#pragma omp atomic' has 'seq_cst' clause.
 class OMPSeqCstClause : public OMPClause {
 public:
   /// Build 'seq_cst' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPSeqCstClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_seq_cst, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPSeqCstClause()
       : OMPClause(OMPC_seq_cst, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_seq_cst;
   }
 };
 
 /// This represents 'acq_rel' clause in the '#pragma omp atomic|flush'
 /// directives.
 ///
 /// \code
 /// #pragma omp flush acq_rel
 /// \endcode
 /// In this example directive '#pragma omp flush' has 'acq_rel' clause.
 class OMPAcqRelClause final : public OMPClause {
 public:
   /// Build 'ack_rel' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPAcqRelClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_acq_rel, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPAcqRelClause()
       : OMPClause(OMPC_acq_rel, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_acq_rel;
   }
 };
 
 /// This represents 'acquire' clause in the '#pragma omp atomic|flush'
 /// directives.
 ///
 /// \code
 /// #pragma omp flush acquire
 /// \endcode
 /// In this example directive '#pragma omp flush' has 'acquire' clause.
 class OMPAcquireClause final : public OMPClause {
 public:
   /// Build 'acquire' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPAcquireClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_acquire, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPAcquireClause()
       : OMPClause(OMPC_acquire, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_acquire;
   }
 };
 
 /// This represents 'release' clause in the '#pragma omp atomic|flush'
 /// directives.
 ///
 /// \code
 /// #pragma omp flush release
 /// \endcode
 /// In this example directive '#pragma omp flush' has 'release' clause.
 class OMPReleaseClause final : public OMPClause {
 public:
   /// Build 'release' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPReleaseClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_release, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPReleaseClause()
       : OMPClause(OMPC_release, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_release;
   }
 };
 
 /// This represents 'relaxed' clause in the '#pragma omp atomic'
 /// directives.
 ///
 /// \code
 /// #pragma omp atomic relaxed
 /// \endcode
 /// In this example directive '#pragma omp atomic' has 'relaxed' clause.
 class OMPRelaxedClause final : public OMPClause {
 public:
   /// Build 'relaxed' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPRelaxedClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_relaxed, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPRelaxedClause()
       : OMPClause(OMPC_relaxed, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_relaxed;
   }
 };
 
 /// This represents clause 'private' in the '#pragma omp ...' directives.
 ///
 /// \code
 /// #pragma omp parallel private(a,b)
 /// \endcode
 /// In this example directive '#pragma omp parallel' has clause 'private'
 /// with the variables 'a' and 'b'.
 class OMPPrivateClause final
     : public OMPVarListClause<OMPPrivateClause>,
       private llvm::TrailingObjects<OMPPrivateClause, Expr *> {
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param N Number of the variables in the clause.
   OMPPrivateClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                    SourceLocation EndLoc, unsigned N)
       : OMPVarListClause<OMPPrivateClause>(OMPC_private, StartLoc, LParenLoc,
                                            EndLoc, N) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPPrivateClause(unsigned N)
       : OMPVarListClause<OMPPrivateClause>(OMPC_private, SourceLocation(),
                                            SourceLocation(), SourceLocation(),
                                            N) {}
 
   /// Sets the list of references to private copies with initializers for
   /// new private variables.
   /// \param VL List of references.
   void setPrivateCopies(ArrayRef<Expr *> VL);
 
   /// Gets the list of references to private copies with initializers for
   /// new private variables.
   MutableArrayRef<Expr *> getPrivateCopies() {
     return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
   }
   ArrayRef<const Expr *> getPrivateCopies() const {
     return llvm::makeArrayRef(varlist_end(), varlist_size());
   }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param VL List of references to the variables.
   /// \param PrivateVL List of references to private copies with initializers.
   static OMPPrivateClause *Create(const ASTContext &C, SourceLocation StartLoc,
                                   SourceLocation LParenLoc,
                                   SourceLocation EndLoc, ArrayRef<Expr *> VL,
                                   ArrayRef<Expr *> PrivateVL);
 
   /// Creates an empty clause with the place for \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPPrivateClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   using private_copies_iterator = MutableArrayRef<Expr *>::iterator;
   using private_copies_const_iterator = ArrayRef<const Expr *>::iterator;
   using private_copies_range = llvm::iterator_range<private_copies_iterator>;
   using private_copies_const_range =
       llvm::iterator_range<private_copies_const_iterator>;
 
   private_copies_range private_copies() {
     return private_copies_range(getPrivateCopies().begin(),
                                 getPrivateCopies().end());
   }
 
   private_copies_const_range private_copies() const {
     return private_copies_const_range(getPrivateCopies().begin(),
                                       getPrivateCopies().end());
   }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPPrivateClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_private;
   }
 };
 
 /// This represents clause 'firstprivate' in the '#pragma omp ...'
 /// directives.
 ///
 /// \code
 /// #pragma omp parallel firstprivate(a,b)
 /// \endcode
 /// In this example directive '#pragma omp parallel' has clause 'firstprivate'
 /// with the variables 'a' and 'b'.
 class OMPFirstprivateClause final
     : public OMPVarListClause<OMPFirstprivateClause>,
       public OMPClauseWithPreInit,
       private llvm::TrailingObjects<OMPFirstprivateClause, Expr *> {
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param N Number of the variables in the clause.
   OMPFirstprivateClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                         SourceLocation EndLoc, unsigned N)
       : OMPVarListClause<OMPFirstprivateClause>(OMPC_firstprivate, StartLoc,
                                                 LParenLoc, EndLoc, N),
         OMPClauseWithPreInit(this) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPFirstprivateClause(unsigned N)
       : OMPVarListClause<OMPFirstprivateClause>(
             OMPC_firstprivate, SourceLocation(), SourceLocation(),
             SourceLocation(), N),
         OMPClauseWithPreInit(this) {}
 
   /// Sets the list of references to private copies with initializers for
   /// new private variables.
   /// \param VL List of references.
   void setPrivateCopies(ArrayRef<Expr *> VL);
 
   /// Gets the list of references to private copies with initializers for
   /// new private variables.
   MutableArrayRef<Expr *> getPrivateCopies() {
     return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
   }
   ArrayRef<const Expr *> getPrivateCopies() const {
     return llvm::makeArrayRef(varlist_end(), varlist_size());
   }
 
   /// Sets the list of references to initializer variables for new
   /// private variables.
   /// \param VL List of references.
   void setInits(ArrayRef<Expr *> VL);
 
   /// Gets the list of references to initializer variables for new
   /// private variables.
   MutableArrayRef<Expr *> getInits() {
     return MutableArrayRef<Expr *>(getPrivateCopies().end(), varlist_size());
   }
   ArrayRef<const Expr *> getInits() const {
     return llvm::makeArrayRef(getPrivateCopies().end(), varlist_size());
   }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param VL List of references to the original variables.
   /// \param PrivateVL List of references to private copies with initializers.
   /// \param InitVL List of references to auto generated variables used for
   /// initialization of a single array element. Used if firstprivate variable is
   /// of array type.
   /// \param PreInit Statement that must be executed before entering the OpenMP
   /// region with this clause.
   static OMPFirstprivateClause *
   Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
          SourceLocation EndLoc, ArrayRef<Expr *> VL, ArrayRef<Expr *> PrivateVL,
          ArrayRef<Expr *> InitVL, Stmt *PreInit);
 
   /// Creates an empty clause with the place for \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPFirstprivateClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   using private_copies_iterator = MutableArrayRef<Expr *>::iterator;
   using private_copies_const_iterator = ArrayRef<const Expr *>::iterator;
   using private_copies_range = llvm::iterator_range<private_copies_iterator>;
   using private_copies_const_range =
       llvm::iterator_range<private_copies_const_iterator>;
 
   private_copies_range private_copies() {
     return private_copies_range(getPrivateCopies().begin(),
                                 getPrivateCopies().end());
   }
   private_copies_const_range private_copies() const {
     return private_copies_const_range(getPrivateCopies().begin(),
                                       getPrivateCopies().end());
   }
 
   using inits_iterator = MutableArrayRef<Expr *>::iterator;
   using inits_const_iterator = ArrayRef<const Expr *>::iterator;
   using inits_range = llvm::iterator_range<inits_iterator>;
   using inits_const_range = llvm::iterator_range<inits_const_iterator>;
 
   inits_range inits() {
     return inits_range(getInits().begin(), getInits().end());
   }
   inits_const_range inits() const {
     return inits_const_range(getInits().begin(), getInits().end());
   }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPFirstprivateClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
   const_child_range used_children() const {
     auto Children = const_cast<OMPFirstprivateClause *>(this)->used_children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_firstprivate;
   }
 };
 
 /// This represents clause 'lastprivate' in the '#pragma omp ...'
 /// directives.
 ///
 /// \code
 /// #pragma omp simd lastprivate(a,b)
 /// \endcode
 /// In this example directive '#pragma omp simd' has clause 'lastprivate'
 /// with the variables 'a' and 'b'.
 class OMPLastprivateClause final
     : public OMPVarListClause<OMPLastprivateClause>,
       public OMPClauseWithPostUpdate,
       private llvm::TrailingObjects<OMPLastprivateClause, Expr *> {
   // There are 4 additional tail-allocated arrays at the end of the class:
   // 1. Contains list of pseudo variables with the default initialization for
   // each non-firstprivate variables. Used in codegen for initialization of
   // lastprivate copies.
   // 2. List of helper expressions for proper generation of assignment operation
   // required for lastprivate clause. This list represents private variables
   // (for arrays, single array element).
   // 3. List of helper expressions for proper generation of assignment operation
   // required for lastprivate clause. This list represents original variables
   // (for arrays, single array element).
   // 4. List of helper expressions that represents assignment operation:
   // \code
   // DstExprs = SrcExprs;
   // \endcode
   // Required for proper codegen of final assignment performed by the
   // lastprivate clause.
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Optional lastprivate kind, e.g. 'conditional', if specified by user.
   OpenMPLastprivateModifier LPKind;
   /// Optional location of the lasptrivate kind, if specified by user.
   SourceLocation LPKindLoc;
   /// Optional colon location, if specified by user.
   SourceLocation ColonLoc;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param N Number of the variables in the clause.
   OMPLastprivateClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                        SourceLocation EndLoc, OpenMPLastprivateModifier LPKind,
                        SourceLocation LPKindLoc, SourceLocation ColonLoc,
                        unsigned N)
       : OMPVarListClause<OMPLastprivateClause>(OMPC_lastprivate, StartLoc,
                                                LParenLoc, EndLoc, N),
         OMPClauseWithPostUpdate(this), LPKind(LPKind), LPKindLoc(LPKindLoc),
         ColonLoc(ColonLoc) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPLastprivateClause(unsigned N)
       : OMPVarListClause<OMPLastprivateClause>(
             OMPC_lastprivate, SourceLocation(), SourceLocation(),
             SourceLocation(), N),
         OMPClauseWithPostUpdate(this) {}
 
   /// Get the list of helper expressions for initialization of private
   /// copies for lastprivate variables.
   MutableArrayRef<Expr *> getPrivateCopies() {
     return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
   }
   ArrayRef<const Expr *> getPrivateCopies() const {
     return llvm::makeArrayRef(varlist_end(), varlist_size());
   }
 
   /// Set list of helper expressions, required for proper codegen of the
   /// clause. These expressions represent private variables (for arrays, single
   /// array element) in the final assignment statement performed by the
   /// lastprivate clause.
   void setSourceExprs(ArrayRef<Expr *> SrcExprs);
 
   /// Get the list of helper source expressions.
   MutableArrayRef<Expr *> getSourceExprs() {
     return MutableArrayRef<Expr *>(getPrivateCopies().end(), varlist_size());
   }
   ArrayRef<const Expr *> getSourceExprs() const {
     return llvm::makeArrayRef(getPrivateCopies().end(), varlist_size());
   }
 
   /// Set list of helper expressions, required for proper codegen of the
   /// clause. These expressions represent original variables (for arrays, single
   /// array element) in the final assignment statement performed by the
   /// lastprivate clause.
   void setDestinationExprs(ArrayRef<Expr *> DstExprs);
 
   /// Get the list of helper destination expressions.
   MutableArrayRef<Expr *> getDestinationExprs() {
     return MutableArrayRef<Expr *>(getSourceExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getDestinationExprs() const {
     return llvm::makeArrayRef(getSourceExprs().end(), varlist_size());
   }
 
   /// Set list of helper assignment expressions, required for proper
   /// codegen of the clause. These expressions are assignment expressions that
   /// assign private copy of the variable to original variable.
   void setAssignmentOps(ArrayRef<Expr *> AssignmentOps);
 
   /// Get the list of helper assignment expressions.
   MutableArrayRef<Expr *> getAssignmentOps() {
     return MutableArrayRef<Expr *>(getDestinationExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getAssignmentOps() const {
     return llvm::makeArrayRef(getDestinationExprs().end(), varlist_size());
   }
 
   /// Sets lastprivate kind.
   void setKind(OpenMPLastprivateModifier Kind) { LPKind = Kind; }
   /// Sets location of the lastprivate kind.
   void setKindLoc(SourceLocation Loc) { LPKindLoc = Loc; }
   /// Sets colon symbol location.
   void setColonLoc(SourceLocation Loc) { ColonLoc = Loc; }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param VL List of references to the variables.
   /// \param SrcExprs List of helper expressions for proper generation of
   /// assignment operation required for lastprivate clause. This list represents
   /// private variables (for arrays, single array element).
   /// \param DstExprs List of helper expressions for proper generation of
   /// assignment operation required for lastprivate clause. This list represents
   /// original variables (for arrays, single array element).
   /// \param AssignmentOps List of helper expressions that represents assignment
   /// operation:
   /// \code
   /// DstExprs = SrcExprs;
   /// \endcode
   /// Required for proper codegen of final assignment performed by the
   /// lastprivate clause.
   /// \param LPKind Lastprivate kind, e.g. 'conditional'.
   /// \param LPKindLoc Location of the lastprivate kind.
   /// \param ColonLoc Location of the ':' symbol if lastprivate kind is used.
   /// \param PreInit Statement that must be executed before entering the OpenMP
   /// region with this clause.
   /// \param PostUpdate Expression that must be executed after exit from the
   /// OpenMP region with this clause.
   static OMPLastprivateClause *
   Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
          SourceLocation EndLoc, ArrayRef<Expr *> VL, ArrayRef<Expr *> SrcExprs,
          ArrayRef<Expr *> DstExprs, ArrayRef<Expr *> AssignmentOps,
          OpenMPLastprivateModifier LPKind, SourceLocation LPKindLoc,
          SourceLocation ColonLoc, Stmt *PreInit, Expr *PostUpdate);
 
   /// Creates an empty clause with the place for \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPLastprivateClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   /// Lastprivate kind.
   OpenMPLastprivateModifier getKind() const { return LPKind; }
   /// Returns the location of the lastprivate kind.
   SourceLocation getKindLoc() const { return LPKindLoc; }
   /// Returns the location of the ':' symbol, if any.
   SourceLocation getColonLoc() const { return ColonLoc; }
 
   using helper_expr_iterator = MutableArrayRef<Expr *>::iterator;
   using helper_expr_const_iterator = ArrayRef<const Expr *>::iterator;
   using helper_expr_range = llvm::iterator_range<helper_expr_iterator>;
   using helper_expr_const_range =
       llvm::iterator_range<helper_expr_const_iterator>;
 
   /// Set list of helper expressions, required for generation of private
   /// copies of original lastprivate variables.
   void setPrivateCopies(ArrayRef<Expr *> PrivateCopies);
 
   helper_expr_const_range private_copies() const {
     return helper_expr_const_range(getPrivateCopies().begin(),
                                    getPrivateCopies().end());
   }
 
   helper_expr_range private_copies() {
     return helper_expr_range(getPrivateCopies().begin(),
                              getPrivateCopies().end());
   }
 
   helper_expr_const_range source_exprs() const {
     return helper_expr_const_range(getSourceExprs().begin(),
                                    getSourceExprs().end());
   }
 
   helper_expr_range source_exprs() {
     return helper_expr_range(getSourceExprs().begin(), getSourceExprs().end());
   }
 
   helper_expr_const_range destination_exprs() const {
     return helper_expr_const_range(getDestinationExprs().begin(),
                                    getDestinationExprs().end());
   }
 
   helper_expr_range destination_exprs() {
     return helper_expr_range(getDestinationExprs().begin(),
                              getDestinationExprs().end());
   }
 
   helper_expr_const_range assignment_ops() const {
     return helper_expr_const_range(getAssignmentOps().begin(),
                                    getAssignmentOps().end());
   }
 
   helper_expr_range assignment_ops() {
     return helper_expr_range(getAssignmentOps().begin(),
                              getAssignmentOps().end());
   }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPLastprivateClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_lastprivate;
   }
 };
 
 /// This represents clause 'shared' in the '#pragma omp ...' directives.
 ///
 /// \code
 /// #pragma omp parallel shared(a,b)
 /// \endcode
 /// In this example directive '#pragma omp parallel' has clause 'shared'
 /// with the variables 'a' and 'b'.
 class OMPSharedClause final
     : public OMPVarListClause<OMPSharedClause>,
       private llvm::TrailingObjects<OMPSharedClause, Expr *> {
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param N Number of the variables in the clause.
   OMPSharedClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                   SourceLocation EndLoc, unsigned N)
       : OMPVarListClause<OMPSharedClause>(OMPC_shared, StartLoc, LParenLoc,
                                           EndLoc, N) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPSharedClause(unsigned N)
       : OMPVarListClause<OMPSharedClause>(OMPC_shared, SourceLocation(),
                                           SourceLocation(), SourceLocation(),
                                           N) {}
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param VL List of references to the variables.
   static OMPSharedClause *Create(const ASTContext &C, SourceLocation StartLoc,
                                  SourceLocation LParenLoc,
                                  SourceLocation EndLoc, ArrayRef<Expr *> VL);
 
   /// Creates an empty clause with \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPSharedClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPSharedClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_shared;
   }
 };
 
 /// This represents clause 'reduction' in the '#pragma omp ...'
 /// directives.
 ///
 /// \code
 /// #pragma omp parallel reduction(+:a,b)
 /// \endcode
 /// In this example directive '#pragma omp parallel' has clause 'reduction'
 /// with operator '+' and the variables 'a' and 'b'.
 class OMPReductionClause final
     : public OMPVarListClause<OMPReductionClause>,
       public OMPClauseWithPostUpdate,
       private llvm::TrailingObjects<OMPReductionClause, Expr *> {
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Location of ':'.
   SourceLocation ColonLoc;
 
   /// Nested name specifier for C++.
   NestedNameSpecifierLoc QualifierLoc;
 
   /// Name of custom operator.
   DeclarationNameInfo NameInfo;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param ColonLoc Location of ':'.
   /// \param N Number of the variables in the clause.
   /// \param QualifierLoc The nested-name qualifier with location information
   /// \param NameInfo The full name info for reduction identifier.
   OMPReductionClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                      SourceLocation ColonLoc, SourceLocation EndLoc, unsigned N,
                      NestedNameSpecifierLoc QualifierLoc,
                      const DeclarationNameInfo &NameInfo)
       : OMPVarListClause<OMPReductionClause>(OMPC_reduction, StartLoc,
                                              LParenLoc, EndLoc, N),
         OMPClauseWithPostUpdate(this), ColonLoc(ColonLoc),
         QualifierLoc(QualifierLoc), NameInfo(NameInfo) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPReductionClause(unsigned N)
       : OMPVarListClause<OMPReductionClause>(OMPC_reduction, SourceLocation(),
                                              SourceLocation(), SourceLocation(),
                                              N),
         OMPClauseWithPostUpdate(this) {}
 
   /// Sets location of ':' symbol in clause.
   void setColonLoc(SourceLocation CL) { ColonLoc = CL; }
 
   /// Sets the name info for specified reduction identifier.
   void setNameInfo(DeclarationNameInfo DNI) { NameInfo = DNI; }
 
   /// Sets the nested name specifier.
   void setQualifierLoc(NestedNameSpecifierLoc NSL) { QualifierLoc = NSL; }
 
   /// Set list of helper expressions, required for proper codegen of the
   /// clause. These expressions represent private copy of the reduction
   /// variable.
   void setPrivates(ArrayRef<Expr *> Privates);
 
   /// Get the list of helper privates.
   MutableArrayRef<Expr *> getPrivates() {
     return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
   }
   ArrayRef<const Expr *> getPrivates() const {
     return llvm::makeArrayRef(varlist_end(), varlist_size());
   }
 
   /// Set list of helper expressions, required for proper codegen of the
   /// clause. These expressions represent LHS expression in the final
   /// reduction expression performed by the reduction clause.
   void setLHSExprs(ArrayRef<Expr *> LHSExprs);
 
   /// Get the list of helper LHS expressions.
   MutableArrayRef<Expr *> getLHSExprs() {
     return MutableArrayRef<Expr *>(getPrivates().end(), varlist_size());
   }
   ArrayRef<const Expr *> getLHSExprs() const {
     return llvm::makeArrayRef(getPrivates().end(), varlist_size());
   }
 
   /// Set list of helper expressions, required for proper codegen of the
   /// clause. These expressions represent RHS expression in the final
   /// reduction expression performed by the reduction clause.
   /// Also, variables in these expressions are used for proper initialization of
   /// reduction copies.
   void setRHSExprs(ArrayRef<Expr *> RHSExprs);
 
   /// Get the list of helper destination expressions.
   MutableArrayRef<Expr *> getRHSExprs() {
     return MutableArrayRef<Expr *>(getLHSExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getRHSExprs() const {
     return llvm::makeArrayRef(getLHSExprs().end(), varlist_size());
   }
 
   /// Set list of helper reduction expressions, required for proper
   /// codegen of the clause. These expressions are binary expressions or
   /// operator/custom reduction call that calculates new value from source
   /// helper expressions to destination helper expressions.
   void setReductionOps(ArrayRef<Expr *> ReductionOps);
 
   /// Get the list of helper reduction expressions.
   MutableArrayRef<Expr *> getReductionOps() {
     return MutableArrayRef<Expr *>(getRHSExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getReductionOps() const {
     return llvm::makeArrayRef(getRHSExprs().end(), varlist_size());
   }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param ColonLoc Location of ':'.
   /// \param EndLoc Ending location of the clause.
   /// \param VL The variables in the clause.
   /// \param QualifierLoc The nested-name qualifier with location information
   /// \param NameInfo The full name info for reduction identifier.
   /// \param Privates List of helper expressions for proper generation of
   /// private copies.
   /// \param LHSExprs List of helper expressions for proper generation of
   /// assignment operation required for copyprivate clause. This list represents
   /// LHSs of the reduction expressions.
   /// \param RHSExprs List of helper expressions for proper generation of
   /// assignment operation required for copyprivate clause. This list represents
   /// RHSs of the reduction expressions.
   /// Also, variables in these expressions are used for proper initialization of
   /// reduction copies.
   /// \param ReductionOps List of helper expressions that represents reduction
   /// expressions:
   /// \code
   /// LHSExprs binop RHSExprs;
   /// operator binop(LHSExpr, RHSExpr);
   /// <CutomReduction>(LHSExpr, RHSExpr);
   /// \endcode
   /// Required for proper codegen of final reduction operation performed by the
   /// reduction clause.
   /// \param PreInit Statement that must be executed before entering the OpenMP
   /// region with this clause.
   /// \param PostUpdate Expression that must be executed after exit from the
   /// OpenMP region with this clause.
   static OMPReductionClause *
   Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
          SourceLocation ColonLoc, SourceLocation EndLoc, ArrayRef<Expr *> VL,
          NestedNameSpecifierLoc QualifierLoc,
          const DeclarationNameInfo &NameInfo, ArrayRef<Expr *> Privates,
          ArrayRef<Expr *> LHSExprs, ArrayRef<Expr *> RHSExprs,
          ArrayRef<Expr *> ReductionOps, Stmt *PreInit, Expr *PostUpdate);
 
   /// Creates an empty clause with the place for \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPReductionClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   /// Gets location of ':' symbol in clause.
   SourceLocation getColonLoc() const { return ColonLoc; }
 
   /// Gets the name info for specified reduction identifier.
   const DeclarationNameInfo &getNameInfo() const { return NameInfo; }
 
   /// Gets the nested name specifier.
   NestedNameSpecifierLoc getQualifierLoc() const { return QualifierLoc; }
 
   using helper_expr_iterator = MutableArrayRef<Expr *>::iterator;
   using helper_expr_const_iterator = ArrayRef<const Expr *>::iterator;
   using helper_expr_range = llvm::iterator_range<helper_expr_iterator>;
   using helper_expr_const_range =
       llvm::iterator_range<helper_expr_const_iterator>;
 
   helper_expr_const_range privates() const {
     return helper_expr_const_range(getPrivates().begin(), getPrivates().end());
   }
 
   helper_expr_range privates() {
     return helper_expr_range(getPrivates().begin(), getPrivates().end());
   }
 
   helper_expr_const_range lhs_exprs() const {
     return helper_expr_const_range(getLHSExprs().begin(), getLHSExprs().end());
   }
 
   helper_expr_range lhs_exprs() {
     return helper_expr_range(getLHSExprs().begin(), getLHSExprs().end());
   }
 
   helper_expr_const_range rhs_exprs() const {
     return helper_expr_const_range(getRHSExprs().begin(), getRHSExprs().end());
   }
 
   helper_expr_range rhs_exprs() {
     return helper_expr_range(getRHSExprs().begin(), getRHSExprs().end());
   }
 
   helper_expr_const_range reduction_ops() const {
     return helper_expr_const_range(getReductionOps().begin(),
                                    getReductionOps().end());
   }
 
   helper_expr_range reduction_ops() {
     return helper_expr_range(getReductionOps().begin(),
                              getReductionOps().end());
   }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPReductionClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
   const_child_range used_children() const {
     auto Children = const_cast<OMPReductionClause *>(this)->used_children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_reduction;
   }
 };
 
 /// This represents clause 'task_reduction' in the '#pragma omp taskgroup'
 /// directives.
 ///
 /// \code
 /// #pragma omp taskgroup task_reduction(+:a,b)
 /// \endcode
 /// In this example directive '#pragma omp taskgroup' has clause
 /// 'task_reduction' with operator '+' and the variables 'a' and 'b'.
 class OMPTaskReductionClause final
     : public OMPVarListClause<OMPTaskReductionClause>,
       public OMPClauseWithPostUpdate,
       private llvm::TrailingObjects<OMPTaskReductionClause, Expr *> {
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Location of ':'.
   SourceLocation ColonLoc;
 
   /// Nested name specifier for C++.
   NestedNameSpecifierLoc QualifierLoc;
 
   /// Name of custom operator.
   DeclarationNameInfo NameInfo;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param ColonLoc Location of ':'.
   /// \param N Number of the variables in the clause.
   /// \param QualifierLoc The nested-name qualifier with location information
   /// \param NameInfo The full name info for reduction identifier.
   OMPTaskReductionClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                          SourceLocation ColonLoc, SourceLocation EndLoc,
                          unsigned N, NestedNameSpecifierLoc QualifierLoc,
                          const DeclarationNameInfo &NameInfo)
       : OMPVarListClause<OMPTaskReductionClause>(OMPC_task_reduction, StartLoc,
                                                  LParenLoc, EndLoc, N),
         OMPClauseWithPostUpdate(this), ColonLoc(ColonLoc),
         QualifierLoc(QualifierLoc), NameInfo(NameInfo) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPTaskReductionClause(unsigned N)
       : OMPVarListClause<OMPTaskReductionClause>(
             OMPC_task_reduction, SourceLocation(), SourceLocation(),
             SourceLocation(), N),
         OMPClauseWithPostUpdate(this) {}
 
   /// Sets location of ':' symbol in clause.
   void setColonLoc(SourceLocation CL) { ColonLoc = CL; }
 
   /// Sets the name info for specified reduction identifier.
   void setNameInfo(DeclarationNameInfo DNI) { NameInfo = DNI; }
 
   /// Sets the nested name specifier.
   void setQualifierLoc(NestedNameSpecifierLoc NSL) { QualifierLoc = NSL; }
 
   /// Set list of helper expressions, required for proper codegen of the clause.
   /// These expressions represent private copy of the reduction variable.
   void setPrivates(ArrayRef<Expr *> Privates);
 
   /// Get the list of helper privates.
   MutableArrayRef<Expr *> getPrivates() {
     return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
   }
   ArrayRef<const Expr *> getPrivates() const {
     return llvm::makeArrayRef(varlist_end(), varlist_size());
   }
 
   /// Set list of helper expressions, required for proper codegen of the clause.
   /// These expressions represent LHS expression in the final reduction
   /// expression performed by the reduction clause.
   void setLHSExprs(ArrayRef<Expr *> LHSExprs);
 
   /// Get the list of helper LHS expressions.
   MutableArrayRef<Expr *> getLHSExprs() {
     return MutableArrayRef<Expr *>(getPrivates().end(), varlist_size());
   }
   ArrayRef<const Expr *> getLHSExprs() const {
     return llvm::makeArrayRef(getPrivates().end(), varlist_size());
   }
 
   /// Set list of helper expressions, required for proper codegen of the clause.
   /// These expressions represent RHS expression in the final reduction
   /// expression performed by the reduction clause. Also, variables in these
   /// expressions are used for proper initialization of reduction copies.
   void setRHSExprs(ArrayRef<Expr *> RHSExprs);
 
   ///  Get the list of helper destination expressions.
   MutableArrayRef<Expr *> getRHSExprs() {
     return MutableArrayRef<Expr *>(getLHSExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getRHSExprs() const {
     return llvm::makeArrayRef(getLHSExprs().end(), varlist_size());
   }
 
   /// Set list of helper reduction expressions, required for proper
   /// codegen of the clause. These expressions are binary expressions or
   /// operator/custom reduction call that calculates new value from source
   /// helper expressions to destination helper expressions.
   void setReductionOps(ArrayRef<Expr *> ReductionOps);
 
   ///  Get the list of helper reduction expressions.
   MutableArrayRef<Expr *> getReductionOps() {
     return MutableArrayRef<Expr *>(getRHSExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getReductionOps() const {
     return llvm::makeArrayRef(getRHSExprs().end(), varlist_size());
   }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param ColonLoc Location of ':'.
   /// \param EndLoc Ending location of the clause.
   /// \param VL The variables in the clause.
   /// \param QualifierLoc The nested-name qualifier with location information
   /// \param NameInfo The full name info for reduction identifier.
   /// \param Privates List of helper expressions for proper generation of
   /// private copies.
   /// \param LHSExprs List of helper expressions for proper generation of
   /// assignment operation required for copyprivate clause. This list represents
   /// LHSs of the reduction expressions.
   /// \param RHSExprs List of helper expressions for proper generation of
   /// assignment operation required for copyprivate clause. This list represents
   /// RHSs of the reduction expressions.
   /// Also, variables in these expressions are used for proper initialization of
   /// reduction copies.
   /// \param ReductionOps List of helper expressions that represents reduction
   /// expressions:
   /// \code
   /// LHSExprs binop RHSExprs;
   /// operator binop(LHSExpr, RHSExpr);
   /// <CutomReduction>(LHSExpr, RHSExpr);
   /// \endcode
   /// Required for proper codegen of final reduction operation performed by the
   /// reduction clause.
   /// \param PreInit Statement that must be executed before entering the OpenMP
   /// region with this clause.
   /// \param PostUpdate Expression that must be executed after exit from the
   /// OpenMP region with this clause.
   static OMPTaskReductionClause *
   Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
          SourceLocation ColonLoc, SourceLocation EndLoc, ArrayRef<Expr *> VL,
          NestedNameSpecifierLoc QualifierLoc,
          const DeclarationNameInfo &NameInfo, ArrayRef<Expr *> Privates,
          ArrayRef<Expr *> LHSExprs, ArrayRef<Expr *> RHSExprs,
          ArrayRef<Expr *> ReductionOps, Stmt *PreInit, Expr *PostUpdate);
 
   /// Creates an empty clause with the place for \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPTaskReductionClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   /// Gets location of ':' symbol in clause.
   SourceLocation getColonLoc() const { return ColonLoc; }
 
   /// Gets the name info for specified reduction identifier.
   const DeclarationNameInfo &getNameInfo() const { return NameInfo; }
 
   /// Gets the nested name specifier.
   NestedNameSpecifierLoc getQualifierLoc() const { return QualifierLoc; }
 
   using helper_expr_iterator = MutableArrayRef<Expr *>::iterator;
   using helper_expr_const_iterator = ArrayRef<const Expr *>::iterator;
   using helper_expr_range = llvm::iterator_range<helper_expr_iterator>;
   using helper_expr_const_range =
       llvm::iterator_range<helper_expr_const_iterator>;
 
   helper_expr_const_range privates() const {
     return helper_expr_const_range(getPrivates().begin(), getPrivates().end());
   }
 
   helper_expr_range privates() {
     return helper_expr_range(getPrivates().begin(), getPrivates().end());
   }
 
   helper_expr_const_range lhs_exprs() const {
     return helper_expr_const_range(getLHSExprs().begin(), getLHSExprs().end());
   }
 
   helper_expr_range lhs_exprs() {
     return helper_expr_range(getLHSExprs().begin(), getLHSExprs().end());
   }
 
   helper_expr_const_range rhs_exprs() const {
     return helper_expr_const_range(getRHSExprs().begin(), getRHSExprs().end());
   }
 
   helper_expr_range rhs_exprs() {
     return helper_expr_range(getRHSExprs().begin(), getRHSExprs().end());
   }
 
   helper_expr_const_range reduction_ops() const {
     return helper_expr_const_range(getReductionOps().begin(),
                                    getReductionOps().end());
   }
 
   helper_expr_range reduction_ops() {
     return helper_expr_range(getReductionOps().begin(),
                              getReductionOps().end());
   }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPTaskReductionClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_task_reduction;
   }
 };
 
 /// This represents clause 'in_reduction' in the '#pragma omp task' directives.
 ///
 /// \code
 /// #pragma omp task in_reduction(+:a,b)
 /// \endcode
 /// In this example directive '#pragma omp task' has clause 'in_reduction' with
 /// operator '+' and the variables 'a' and 'b'.
 class OMPInReductionClause final
     : public OMPVarListClause<OMPInReductionClause>,
       public OMPClauseWithPostUpdate,
       private llvm::TrailingObjects<OMPInReductionClause, Expr *> {
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Location of ':'.
   SourceLocation ColonLoc;
 
   /// Nested name specifier for C++.
   NestedNameSpecifierLoc QualifierLoc;
 
   /// Name of custom operator.
   DeclarationNameInfo NameInfo;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param ColonLoc Location of ':'.
   /// \param N Number of the variables in the clause.
   /// \param QualifierLoc The nested-name qualifier with location information
   /// \param NameInfo The full name info for reduction identifier.
   OMPInReductionClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                        SourceLocation ColonLoc, SourceLocation EndLoc,
                        unsigned N, NestedNameSpecifierLoc QualifierLoc,
                        const DeclarationNameInfo &NameInfo)
       : OMPVarListClause<OMPInReductionClause>(OMPC_in_reduction, StartLoc,
                                                LParenLoc, EndLoc, N),
         OMPClauseWithPostUpdate(this), ColonLoc(ColonLoc),
         QualifierLoc(QualifierLoc), NameInfo(NameInfo) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPInReductionClause(unsigned N)
       : OMPVarListClause<OMPInReductionClause>(
             OMPC_in_reduction, SourceLocation(), SourceLocation(),
             SourceLocation(), N),
         OMPClauseWithPostUpdate(this) {}
 
   /// Sets location of ':' symbol in clause.
   void setColonLoc(SourceLocation CL) { ColonLoc = CL; }
 
   /// Sets the name info for specified reduction identifier.
   void setNameInfo(DeclarationNameInfo DNI) { NameInfo = DNI; }
 
   /// Sets the nested name specifier.
   void setQualifierLoc(NestedNameSpecifierLoc NSL) { QualifierLoc = NSL; }
 
   /// Set list of helper expressions, required for proper codegen of the clause.
   /// These expressions represent private copy of the reduction variable.
   void setPrivates(ArrayRef<Expr *> Privates);
 
   /// Get the list of helper privates.
   MutableArrayRef<Expr *> getPrivates() {
     return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
   }
   ArrayRef<const Expr *> getPrivates() const {
     return llvm::makeArrayRef(varlist_end(), varlist_size());
   }
 
   /// Set list of helper expressions, required for proper codegen of the clause.
   /// These expressions represent LHS expression in the final reduction
   /// expression performed by the reduction clause.
   void setLHSExprs(ArrayRef<Expr *> LHSExprs);
 
   /// Get the list of helper LHS expressions.
   MutableArrayRef<Expr *> getLHSExprs() {
     return MutableArrayRef<Expr *>(getPrivates().end(), varlist_size());
   }
   ArrayRef<const Expr *> getLHSExprs() const {
     return llvm::makeArrayRef(getPrivates().end(), varlist_size());
   }
 
   /// Set list of helper expressions, required for proper codegen of the clause.
   /// These expressions represent RHS expression in the final reduction
   /// expression performed by the reduction clause. Also, variables in these
   /// expressions are used for proper initialization of reduction copies.
   void setRHSExprs(ArrayRef<Expr *> RHSExprs);
 
   ///  Get the list of helper destination expressions.
   MutableArrayRef<Expr *> getRHSExprs() {
     return MutableArrayRef<Expr *>(getLHSExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getRHSExprs() const {
     return llvm::makeArrayRef(getLHSExprs().end(), varlist_size());
   }
 
   /// Set list of helper reduction expressions, required for proper
   /// codegen of the clause. These expressions are binary expressions or
   /// operator/custom reduction call that calculates new value from source
   /// helper expressions to destination helper expressions.
   void setReductionOps(ArrayRef<Expr *> ReductionOps);
 
   ///  Get the list of helper reduction expressions.
   MutableArrayRef<Expr *> getReductionOps() {
     return MutableArrayRef<Expr *>(getRHSExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getReductionOps() const {
     return llvm::makeArrayRef(getRHSExprs().end(), varlist_size());
   }
 
   /// Set list of helper reduction taskgroup descriptors.
   void setTaskgroupDescriptors(ArrayRef<Expr *> ReductionOps);
 
   ///  Get the list of helper reduction taskgroup descriptors.
   MutableArrayRef<Expr *> getTaskgroupDescriptors() {
     return MutableArrayRef<Expr *>(getReductionOps().end(), varlist_size());
   }
   ArrayRef<const Expr *> getTaskgroupDescriptors() const {
     return llvm::makeArrayRef(getReductionOps().end(), varlist_size());
   }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param ColonLoc Location of ':'.
   /// \param EndLoc Ending location of the clause.
   /// \param VL The variables in the clause.
   /// \param QualifierLoc The nested-name qualifier with location information
   /// \param NameInfo The full name info for reduction identifier.
   /// \param Privates List of helper expressions for proper generation of
   /// private copies.
   /// \param LHSExprs List of helper expressions for proper generation of
   /// assignment operation required for copyprivate clause. This list represents
   /// LHSs of the reduction expressions.
   /// \param RHSExprs List of helper expressions for proper generation of
   /// assignment operation required for copyprivate clause. This list represents
   /// RHSs of the reduction expressions.
   /// Also, variables in these expressions are used for proper initialization of
   /// reduction copies.
   /// \param ReductionOps List of helper expressions that represents reduction
   /// expressions:
   /// \code
   /// LHSExprs binop RHSExprs;
   /// operator binop(LHSExpr, RHSExpr);
   /// <CutomReduction>(LHSExpr, RHSExpr);
   /// \endcode
   /// Required for proper codegen of final reduction operation performed by the
   /// reduction clause.
   /// \param TaskgroupDescriptors List of helper taskgroup descriptors for
   /// corresponding items in parent taskgroup task_reduction clause.
   /// \param PreInit Statement that must be executed before entering the OpenMP
   /// region with this clause.
   /// \param PostUpdate Expression that must be executed after exit from the
   /// OpenMP region with this clause.
   static OMPInReductionClause *
   Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
          SourceLocation ColonLoc, SourceLocation EndLoc, ArrayRef<Expr *> VL,
          NestedNameSpecifierLoc QualifierLoc,
          const DeclarationNameInfo &NameInfo, ArrayRef<Expr *> Privates,
          ArrayRef<Expr *> LHSExprs, ArrayRef<Expr *> RHSExprs,
          ArrayRef<Expr *> ReductionOps, ArrayRef<Expr *> TaskgroupDescriptors,
          Stmt *PreInit, Expr *PostUpdate);
 
   /// Creates an empty clause with the place for \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPInReductionClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   /// Gets location of ':' symbol in clause.
   SourceLocation getColonLoc() const { return ColonLoc; }
 
   /// Gets the name info for specified reduction identifier.
   const DeclarationNameInfo &getNameInfo() const { return NameInfo; }
 
   /// Gets the nested name specifier.
   NestedNameSpecifierLoc getQualifierLoc() const { return QualifierLoc; }
 
   using helper_expr_iterator = MutableArrayRef<Expr *>::iterator;
   using helper_expr_const_iterator = ArrayRef<const Expr *>::iterator;
   using helper_expr_range = llvm::iterator_range<helper_expr_iterator>;
   using helper_expr_const_range =
       llvm::iterator_range<helper_expr_const_iterator>;
 
   helper_expr_const_range privates() const {
     return helper_expr_const_range(getPrivates().begin(), getPrivates().end());
   }
 
   helper_expr_range privates() {
     return helper_expr_range(getPrivates().begin(), getPrivates().end());
   }
 
   helper_expr_const_range lhs_exprs() const {
     return helper_expr_const_range(getLHSExprs().begin(), getLHSExprs().end());
   }
 
   helper_expr_range lhs_exprs() {
     return helper_expr_range(getLHSExprs().begin(), getLHSExprs().end());
   }
 
   helper_expr_const_range rhs_exprs() const {
     return helper_expr_const_range(getRHSExprs().begin(), getRHSExprs().end());
   }
 
   helper_expr_range rhs_exprs() {
     return helper_expr_range(getRHSExprs().begin(), getRHSExprs().end());
   }
 
   helper_expr_const_range reduction_ops() const {
     return helper_expr_const_range(getReductionOps().begin(),
                                    getReductionOps().end());
   }
 
   helper_expr_range reduction_ops() {
     return helper_expr_range(getReductionOps().begin(),
                              getReductionOps().end());
   }
 
   helper_expr_const_range taskgroup_descriptors() const {
     return helper_expr_const_range(getTaskgroupDescriptors().begin(),
                                    getTaskgroupDescriptors().end());
   }
 
   helper_expr_range taskgroup_descriptors() {
     return helper_expr_range(getTaskgroupDescriptors().begin(),
                              getTaskgroupDescriptors().end());
   }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPInReductionClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_in_reduction;
   }
 };
 
 /// This represents clause 'linear' in the '#pragma omp ...'
 /// directives.
 ///
 /// \code
 /// #pragma omp simd linear(a,b : 2)
 /// \endcode
 /// In this example directive '#pragma omp simd' has clause 'linear'
 /// with variables 'a', 'b' and linear step '2'.
 class OMPLinearClause final
     : public OMPVarListClause<OMPLinearClause>,
       public OMPClauseWithPostUpdate,
       private llvm::TrailingObjects<OMPLinearClause, Expr *> {
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Modifier of 'linear' clause.
   OpenMPLinearClauseKind Modifier = OMPC_LINEAR_val;
 
   /// Location of linear modifier if any.
   SourceLocation ModifierLoc;
 
   /// Location of ':'.
   SourceLocation ColonLoc;
 
   /// Sets the linear step for clause.
   void setStep(Expr *Step) { *(getFinals().end()) = Step; }
 
   /// Sets the expression to calculate linear step for clause.
   void setCalcStep(Expr *CalcStep) { *(getFinals().end() + 1) = CalcStep; }
 
   /// Build 'linear' clause with given number of variables \a NumVars.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param ColonLoc Location of ':'.
   /// \param EndLoc Ending location of the clause.
   /// \param NumVars Number of variables.
   OMPLinearClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                   OpenMPLinearClauseKind Modifier, SourceLocation ModifierLoc,
                   SourceLocation ColonLoc, SourceLocation EndLoc,
                   unsigned NumVars)
       : OMPVarListClause<OMPLinearClause>(OMPC_linear, StartLoc, LParenLoc,
                                           EndLoc, NumVars),
         OMPClauseWithPostUpdate(this), Modifier(Modifier),
         ModifierLoc(ModifierLoc), ColonLoc(ColonLoc) {}
 
   /// Build an empty clause.
   ///
   /// \param NumVars Number of variables.
   explicit OMPLinearClause(unsigned NumVars)
       : OMPVarListClause<OMPLinearClause>(OMPC_linear, SourceLocation(),
                                           SourceLocation(), SourceLocation(),
                                           NumVars),
         OMPClauseWithPostUpdate(this) {}
 
   /// Gets the list of initial values for linear variables.
   ///
   /// There are NumVars expressions with initial values allocated after the
   /// varlist, they are followed by NumVars update expressions (used to update
   /// the linear variable's value on current iteration) and they are followed by
   /// NumVars final expressions (used to calculate the linear variable's
   /// value after the loop body). After these lists, there are 2 helper
   /// expressions - linear step and a helper to calculate it before the
   /// loop body (used when the linear step is not constant):
   ///
   /// { Vars[] /* in OMPVarListClause */; Privates[]; Inits[]; Updates[];
   /// Finals[]; Step; CalcStep; }
   MutableArrayRef<Expr *> getPrivates() {
     return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
   }
   ArrayRef<const Expr *> getPrivates() const {
     return llvm::makeArrayRef(varlist_end(), varlist_size());
   }
 
   MutableArrayRef<Expr *> getInits() {
     return MutableArrayRef<Expr *>(getPrivates().end(), varlist_size());
   }
   ArrayRef<const Expr *> getInits() const {
     return llvm::makeArrayRef(getPrivates().end(), varlist_size());
   }
 
   /// Sets the list of update expressions for linear variables.
   MutableArrayRef<Expr *> getUpdates() {
     return MutableArrayRef<Expr *>(getInits().end(), varlist_size());
   }
   ArrayRef<const Expr *> getUpdates() const {
     return llvm::makeArrayRef(getInits().end(), varlist_size());
   }
 
   /// Sets the list of final update expressions for linear variables.
   MutableArrayRef<Expr *> getFinals() {
     return MutableArrayRef<Expr *>(getUpdates().end(), varlist_size());
   }
   ArrayRef<const Expr *> getFinals() const {
     return llvm::makeArrayRef(getUpdates().end(), varlist_size());
   }
 
   /// Gets the list of used expressions for linear variables.
   MutableArrayRef<Expr *> getUsedExprs() {
     return MutableArrayRef<Expr *>(getFinals().end() + 2, varlist_size() + 1);
   }
   ArrayRef<const Expr *> getUsedExprs() const {
     return llvm::makeArrayRef(getFinals().end() + 2, varlist_size() + 1);
   }
 
   /// Sets the list of the copies of original linear variables.
   /// \param PL List of expressions.
   void setPrivates(ArrayRef<Expr *> PL);
 
   /// Sets the list of the initial values for linear variables.
   /// \param IL List of expressions.
   void setInits(ArrayRef<Expr *> IL);
 
 public:
   /// Creates clause with a list of variables \a VL and a linear step
   /// \a Step.
   ///
   /// \param C AST Context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param Modifier Modifier of 'linear' clause.
   /// \param ModifierLoc Modifier location.
   /// \param ColonLoc Location of ':'.
   /// \param EndLoc Ending location of the clause.
   /// \param VL List of references to the variables.
   /// \param PL List of private copies of original variables.
   /// \param IL List of initial values for the variables.
   /// \param Step Linear step.
   /// \param CalcStep Calculation of the linear step.
   /// \param PreInit Statement that must be executed before entering the OpenMP
   /// region with this clause.
   /// \param PostUpdate Expression that must be executed after exit from the
   /// OpenMP region with this clause.
   static OMPLinearClause *
   Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
          OpenMPLinearClauseKind Modifier, SourceLocation ModifierLoc,
          SourceLocation ColonLoc, SourceLocation EndLoc, ArrayRef<Expr *> VL,
          ArrayRef<Expr *> PL, ArrayRef<Expr *> IL, Expr *Step, Expr *CalcStep,
          Stmt *PreInit, Expr *PostUpdate);
 
   /// Creates an empty clause with the place for \a NumVars variables.
   ///
   /// \param C AST context.
   /// \param NumVars Number of variables.
   static OMPLinearClause *CreateEmpty(const ASTContext &C, unsigned NumVars);
 
   /// Set modifier.
   void setModifier(OpenMPLinearClauseKind Kind) { Modifier = Kind; }
 
   /// Return modifier.
   OpenMPLinearClauseKind getModifier() const { return Modifier; }
 
   /// Set modifier location.
   void setModifierLoc(SourceLocation Loc) { ModifierLoc = Loc; }
 
   /// Return modifier location.
   SourceLocation getModifierLoc() const { return ModifierLoc; }
 
   /// Sets the location of ':'.
   void setColonLoc(SourceLocation Loc) { ColonLoc = Loc; }
 
   /// Returns the location of ':'.
   SourceLocation getColonLoc() const { return ColonLoc; }
 
   /// Returns linear step.
   Expr *getStep() { return *(getFinals().end()); }
 
   /// Returns linear step.
   const Expr *getStep() const { return *(getFinals().end()); }
 
   /// Returns expression to calculate linear step.
   Expr *getCalcStep() { return *(getFinals().end() + 1); }
 
   /// Returns expression to calculate linear step.
   const Expr *getCalcStep() const { return *(getFinals().end() + 1); }
 
   /// Sets the list of update expressions for linear variables.
   /// \param UL List of expressions.
   void setUpdates(ArrayRef<Expr *> UL);
 
   /// Sets the list of final update expressions for linear variables.
   /// \param FL List of expressions.
   void setFinals(ArrayRef<Expr *> FL);
 
   /// Sets the list of used expressions for the linear clause.
   void setUsedExprs(ArrayRef<Expr *> UE);
 
   using privates_iterator = MutableArrayRef<Expr *>::iterator;
   using privates_const_iterator = ArrayRef<const Expr *>::iterator;
   using privates_range = llvm::iterator_range<privates_iterator>;
   using privates_const_range = llvm::iterator_range<privates_const_iterator>;
 
   privates_range privates() {
     return privates_range(getPrivates().begin(), getPrivates().end());
   }
 
   privates_const_range privates() const {
     return privates_const_range(getPrivates().begin(), getPrivates().end());
   }
 
   using inits_iterator = MutableArrayRef<Expr *>::iterator;
   using inits_const_iterator = ArrayRef<const Expr *>::iterator;
   using inits_range = llvm::iterator_range<inits_iterator>;
   using inits_const_range = llvm::iterator_range<inits_const_iterator>;
 
   inits_range inits() {
     return inits_range(getInits().begin(), getInits().end());
   }
 
   inits_const_range inits() const {
     return inits_const_range(getInits().begin(), getInits().end());
   }
 
   using updates_iterator = MutableArrayRef<Expr *>::iterator;
   using updates_const_iterator = ArrayRef<const Expr *>::iterator;
   using updates_range = llvm::iterator_range<updates_iterator>;
   using updates_const_range = llvm::iterator_range<updates_const_iterator>;
 
   updates_range updates() {
     return updates_range(getUpdates().begin(), getUpdates().end());
   }
 
   updates_const_range updates() const {
     return updates_const_range(getUpdates().begin(), getUpdates().end());
   }
 
   using finals_iterator = MutableArrayRef<Expr *>::iterator;
   using finals_const_iterator = ArrayRef<const Expr *>::iterator;
   using finals_range = llvm::iterator_range<finals_iterator>;
   using finals_const_range = llvm::iterator_range<finals_const_iterator>;
 
   finals_range finals() {
     return finals_range(getFinals().begin(), getFinals().end());
   }
 
   finals_const_range finals() const {
     return finals_const_range(getFinals().begin(), getFinals().end());
   }
 
   using used_expressions_iterator = MutableArrayRef<Expr *>::iterator;
   using used_expressions_const_iterator = ArrayRef<const Expr *>::iterator;
   using used_expressions_range =
       llvm::iterator_range<used_expressions_iterator>;
   using used_expressions_const_range =
       llvm::iterator_range<used_expressions_const_iterator>;
 
   used_expressions_range used_expressions() {
     return finals_range(getUsedExprs().begin(), getUsedExprs().end());
   }
 
   used_expressions_const_range used_expressions() const {
     return finals_const_range(getUsedExprs().begin(), getUsedExprs().end());
   }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPLinearClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children();
 
   const_child_range used_children() const {
     auto Children = const_cast<OMPLinearClause *>(this)->used_children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_linear;
   }
 };
 
 /// This represents clause 'aligned' in the '#pragma omp ...'
 /// directives.
 ///
 /// \code
 /// #pragma omp simd aligned(a,b : 8)
 /// \endcode
 /// In this example directive '#pragma omp simd' has clause 'aligned'
 /// with variables 'a', 'b' and alignment '8'.
 class OMPAlignedClause final
     : public OMPVarListClause<OMPAlignedClause>,
       private llvm::TrailingObjects<OMPAlignedClause, Expr *> {
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Location of ':'.
   SourceLocation ColonLoc;
 
   /// Sets the alignment for clause.
   void setAlignment(Expr *A) { *varlist_end() = A; }
 
   /// Build 'aligned' clause with given number of variables \a NumVars.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param ColonLoc Location of ':'.
   /// \param EndLoc Ending location of the clause.
   /// \param NumVars Number of variables.
   OMPAlignedClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                    SourceLocation ColonLoc, SourceLocation EndLoc,
                    unsigned NumVars)
       : OMPVarListClause<OMPAlignedClause>(OMPC_aligned, StartLoc, LParenLoc,
                                            EndLoc, NumVars),
         ColonLoc(ColonLoc) {}
 
   /// Build an empty clause.
   ///
   /// \param NumVars Number of variables.
   explicit OMPAlignedClause(unsigned NumVars)
       : OMPVarListClause<OMPAlignedClause>(OMPC_aligned, SourceLocation(),
                                            SourceLocation(), SourceLocation(),
                                            NumVars) {}
 
 public:
   /// Creates clause with a list of variables \a VL and alignment \a A.
   ///
   /// \param C AST Context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param ColonLoc Location of ':'.
   /// \param EndLoc Ending location of the clause.
   /// \param VL List of references to the variables.
   /// \param A Alignment.
   static OMPAlignedClause *Create(const ASTContext &C, SourceLocation StartLoc,
                                   SourceLocation LParenLoc,
                                   SourceLocation ColonLoc,
                                   SourceLocation EndLoc, ArrayRef<Expr *> VL,
                                   Expr *A);
 
   /// Creates an empty clause with the place for \a NumVars variables.
   ///
   /// \param C AST context.
   /// \param NumVars Number of variables.
   static OMPAlignedClause *CreateEmpty(const ASTContext &C, unsigned NumVars);
 
   /// Sets the location of ':'.
   void setColonLoc(SourceLocation Loc) { ColonLoc = Loc; }
 
   /// Returns the location of ':'.
   SourceLocation getColonLoc() const { return ColonLoc; }
 
   /// Returns alignment.
   Expr *getAlignment() { return *varlist_end(); }
 
   /// Returns alignment.
   const Expr *getAlignment() const { return *varlist_end(); }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPAlignedClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_aligned;
   }
 };
 
 /// This represents clause 'copyin' in the '#pragma omp ...' directives.
 ///
 /// \code
 /// #pragma omp parallel copyin(a,b)
 /// \endcode
 /// In this example directive '#pragma omp parallel' has clause 'copyin'
 /// with the variables 'a' and 'b'.
 class OMPCopyinClause final
     : public OMPVarListClause<OMPCopyinClause>,
       private llvm::TrailingObjects<OMPCopyinClause, Expr *> {
   // Class has 3 additional tail allocated arrays:
   // 1. List of helper expressions for proper generation of assignment operation
   // required for copyin clause. This list represents sources.
   // 2. List of helper expressions for proper generation of assignment operation
   // required for copyin clause. This list represents destinations.
   // 3. List of helper expressions that represents assignment operation:
   // \code
   // DstExprs = SrcExprs;
   // \endcode
   // Required for proper codegen of propagation of master's thread values of
   // threadprivate variables to local instances of that variables in other
   // implicit threads.
 
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param N Number of the variables in the clause.
   OMPCopyinClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                   SourceLocation EndLoc, unsigned N)
       : OMPVarListClause<OMPCopyinClause>(OMPC_copyin, StartLoc, LParenLoc,
                                           EndLoc, N) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPCopyinClause(unsigned N)
       : OMPVarListClause<OMPCopyinClause>(OMPC_copyin, SourceLocation(),
                                           SourceLocation(), SourceLocation(),
                                           N) {}
 
   /// Set list of helper expressions, required for proper codegen of the
   /// clause. These expressions represent source expression in the final
   /// assignment statement performed by the copyin clause.
   void setSourceExprs(ArrayRef<Expr *> SrcExprs);
 
   /// Get the list of helper source expressions.
   MutableArrayRef<Expr *> getSourceExprs() {
     return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
   }
   ArrayRef<const Expr *> getSourceExprs() const {
     return llvm::makeArrayRef(varlist_end(), varlist_size());
   }
 
   /// Set list of helper expressions, required for proper codegen of the
   /// clause. These expressions represent destination expression in the final
   /// assignment statement performed by the copyin clause.
   void setDestinationExprs(ArrayRef<Expr *> DstExprs);
 
   /// Get the list of helper destination expressions.
   MutableArrayRef<Expr *> getDestinationExprs() {
     return MutableArrayRef<Expr *>(getSourceExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getDestinationExprs() const {
     return llvm::makeArrayRef(getSourceExprs().end(), varlist_size());
   }
 
   /// Set list of helper assignment expressions, required for proper
   /// codegen of the clause. These expressions are assignment expressions that
   /// assign source helper expressions to destination helper expressions
   /// correspondingly.
   void setAssignmentOps(ArrayRef<Expr *> AssignmentOps);
 
   /// Get the list of helper assignment expressions.
   MutableArrayRef<Expr *> getAssignmentOps() {
     return MutableArrayRef<Expr *>(getDestinationExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getAssignmentOps() const {
     return llvm::makeArrayRef(getDestinationExprs().end(), varlist_size());
   }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param VL List of references to the variables.
   /// \param SrcExprs List of helper expressions for proper generation of
   /// assignment operation required for copyin clause. This list represents
   /// sources.
   /// \param DstExprs List of helper expressions for proper generation of
   /// assignment operation required for copyin clause. This list represents
   /// destinations.
   /// \param AssignmentOps List of helper expressions that represents assignment
   /// operation:
   /// \code
   /// DstExprs = SrcExprs;
   /// \endcode
   /// Required for proper codegen of propagation of master's thread values of
   /// threadprivate variables to local instances of that variables in other
   /// implicit threads.
   static OMPCopyinClause *
   Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
          SourceLocation EndLoc, ArrayRef<Expr *> VL, ArrayRef<Expr *> SrcExprs,
          ArrayRef<Expr *> DstExprs, ArrayRef<Expr *> AssignmentOps);
 
   /// Creates an empty clause with \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPCopyinClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   using helper_expr_iterator = MutableArrayRef<Expr *>::iterator;
   using helper_expr_const_iterator = ArrayRef<const Expr *>::iterator;
   using helper_expr_range = llvm::iterator_range<helper_expr_iterator>;
   using helper_expr_const_range =
       llvm::iterator_range<helper_expr_const_iterator>;
 
   helper_expr_const_range source_exprs() const {
     return helper_expr_const_range(getSourceExprs().begin(),
                                    getSourceExprs().end());
   }
 
   helper_expr_range source_exprs() {
     return helper_expr_range(getSourceExprs().begin(), getSourceExprs().end());
   }
 
   helper_expr_const_range destination_exprs() const {
     return helper_expr_const_range(getDestinationExprs().begin(),
                                    getDestinationExprs().end());
   }
 
   helper_expr_range destination_exprs() {
     return helper_expr_range(getDestinationExprs().begin(),
                              getDestinationExprs().end());
   }
 
   helper_expr_const_range assignment_ops() const {
     return helper_expr_const_range(getAssignmentOps().begin(),
                                    getAssignmentOps().end());
   }
 
   helper_expr_range assignment_ops() {
     return helper_expr_range(getAssignmentOps().begin(),
                              getAssignmentOps().end());
   }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPCopyinClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_copyin;
   }
 };
 
 /// This represents clause 'copyprivate' in the '#pragma omp ...'
 /// directives.
 ///
 /// \code
 /// #pragma omp single copyprivate(a,b)
 /// \endcode
 /// In this example directive '#pragma omp single' has clause 'copyprivate'
 /// with the variables 'a' and 'b'.
 class OMPCopyprivateClause final
     : public OMPVarListClause<OMPCopyprivateClause>,
       private llvm::TrailingObjects<OMPCopyprivateClause, Expr *> {
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param N Number of the variables in the clause.
   OMPCopyprivateClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                        SourceLocation EndLoc, unsigned N)
       : OMPVarListClause<OMPCopyprivateClause>(OMPC_copyprivate, StartLoc,
                                                LParenLoc, EndLoc, N) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPCopyprivateClause(unsigned N)
       : OMPVarListClause<OMPCopyprivateClause>(
             OMPC_copyprivate, SourceLocation(), SourceLocation(),
             SourceLocation(), N) {}
 
   /// Set list of helper expressions, required for proper codegen of the
   /// clause. These expressions represent source expression in the final
   /// assignment statement performed by the copyprivate clause.
   void setSourceExprs(ArrayRef<Expr *> SrcExprs);
 
   /// Get the list of helper source expressions.
   MutableArrayRef<Expr *> getSourceExprs() {
     return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
   }
   ArrayRef<const Expr *> getSourceExprs() const {
     return llvm::makeArrayRef(varlist_end(), varlist_size());
   }
 
   /// Set list of helper expressions, required for proper codegen of the
   /// clause. These expressions represent destination expression in the final
   /// assignment statement performed by the copyprivate clause.
   void setDestinationExprs(ArrayRef<Expr *> DstExprs);
 
   /// Get the list of helper destination expressions.
   MutableArrayRef<Expr *> getDestinationExprs() {
     return MutableArrayRef<Expr *>(getSourceExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getDestinationExprs() const {
     return llvm::makeArrayRef(getSourceExprs().end(), varlist_size());
   }
 
   /// Set list of helper assignment expressions, required for proper
   /// codegen of the clause. These expressions are assignment expressions that
   /// assign source helper expressions to destination helper expressions
   /// correspondingly.
   void setAssignmentOps(ArrayRef<Expr *> AssignmentOps);
 
   /// Get the list of helper assignment expressions.
   MutableArrayRef<Expr *> getAssignmentOps() {
     return MutableArrayRef<Expr *>(getDestinationExprs().end(), varlist_size());
   }
   ArrayRef<const Expr *> getAssignmentOps() const {
     return llvm::makeArrayRef(getDestinationExprs().end(), varlist_size());
   }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param VL List of references to the variables.
   /// \param SrcExprs List of helper expressions for proper generation of
   /// assignment operation required for copyprivate clause. This list represents
   /// sources.
   /// \param DstExprs List of helper expressions for proper generation of
   /// assignment operation required for copyprivate clause. This list represents
   /// destinations.
   /// \param AssignmentOps List of helper expressions that represents assignment
   /// operation:
   /// \code
   /// DstExprs = SrcExprs;
   /// \endcode
   /// Required for proper codegen of final assignment performed by the
   /// copyprivate clause.
   static OMPCopyprivateClause *
   Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
          SourceLocation EndLoc, ArrayRef<Expr *> VL, ArrayRef<Expr *> SrcExprs,
          ArrayRef<Expr *> DstExprs, ArrayRef<Expr *> AssignmentOps);
 
   /// Creates an empty clause with \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPCopyprivateClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   using helper_expr_iterator = MutableArrayRef<Expr *>::iterator;
   using helper_expr_const_iterator = ArrayRef<const Expr *>::iterator;
   using helper_expr_range = llvm::iterator_range<helper_expr_iterator>;
   using helper_expr_const_range =
       llvm::iterator_range<helper_expr_const_iterator>;
 
   helper_expr_const_range source_exprs() const {
     return helper_expr_const_range(getSourceExprs().begin(),
                                    getSourceExprs().end());
   }
 
   helper_expr_range source_exprs() {
     return helper_expr_range(getSourceExprs().begin(), getSourceExprs().end());
   }
 
   helper_expr_const_range destination_exprs() const {
     return helper_expr_const_range(getDestinationExprs().begin(),
                                    getDestinationExprs().end());
   }
 
   helper_expr_range destination_exprs() {
     return helper_expr_range(getDestinationExprs().begin(),
                              getDestinationExprs().end());
   }
 
   helper_expr_const_range assignment_ops() const {
     return helper_expr_const_range(getAssignmentOps().begin(),
                                    getAssignmentOps().end());
   }
 
   helper_expr_range assignment_ops() {
     return helper_expr_range(getAssignmentOps().begin(),
                              getAssignmentOps().end());
   }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPCopyprivateClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_copyprivate;
   }
 };
 
 /// This represents implicit clause 'flush' for the '#pragma omp flush'
 /// directive.
 /// This clause does not exist by itself, it can be only as a part of 'omp
 /// flush' directive. This clause is introduced to keep the original structure
 /// of \a OMPExecutableDirective class and its derivatives and to use the
 /// existing infrastructure of clauses with the list of variables.
 ///
 /// \code
 /// #pragma omp flush(a,b)
 /// \endcode
 /// In this example directive '#pragma omp flush' has implicit clause 'flush'
 /// with the variables 'a' and 'b'.
 class OMPFlushClause final
     : public OMPVarListClause<OMPFlushClause>,
       private llvm::TrailingObjects<OMPFlushClause, Expr *> {
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param N Number of the variables in the clause.
   OMPFlushClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                  SourceLocation EndLoc, unsigned N)
       : OMPVarListClause<OMPFlushClause>(OMPC_flush, StartLoc, LParenLoc,
                                          EndLoc, N) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPFlushClause(unsigned N)
       : OMPVarListClause<OMPFlushClause>(OMPC_flush, SourceLocation(),
                                          SourceLocation(), SourceLocation(),
                                          N) {}
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param VL List of references to the variables.
   static OMPFlushClause *Create(const ASTContext &C, SourceLocation StartLoc,
                                 SourceLocation LParenLoc, SourceLocation EndLoc,
                                 ArrayRef<Expr *> VL);
 
   /// Creates an empty clause with \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPFlushClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPFlushClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_flush;
   }
 };
 
 /// This represents implicit clause 'depobj' for the '#pragma omp depobj'
 /// directive.
 /// This clause does not exist by itself, it can be only as a part of 'omp
 /// depobj' directive. This clause is introduced to keep the original structure
 /// of \a OMPExecutableDirective class and its derivatives and to use the
 /// existing infrastructure of clauses with the list of variables.
 ///
 /// \code
 /// #pragma omp depobj(a) destroy
 /// \endcode
 /// In this example directive '#pragma omp depobj' has implicit clause 'depobj'
 /// with the depobj 'a'.
 class OMPDepobjClause final : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Chunk size.
   Expr *Depobj = nullptr;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPDepobjClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                   SourceLocation EndLoc)
       : OMPClause(OMPC_depobj, StartLoc, EndLoc), LParenLoc(LParenLoc) {}
 
   /// Build an empty clause.
   ///
   explicit OMPDepobjClause()
       : OMPClause(OMPC_depobj, SourceLocation(), SourceLocation()) {}
 
   void setDepobj(Expr *E) { Depobj = E; }
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
 public:
   /// Creates clause.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param Depobj depobj expression associated with the 'depobj' directive.
   static OMPDepobjClause *Create(const ASTContext &C, SourceLocation StartLoc,
                                  SourceLocation LParenLoc,
                                  SourceLocation EndLoc, Expr *Depobj);
 
   /// Creates an empty clause.
   ///
   /// \param C AST context.
   static OMPDepobjClause *CreateEmpty(const ASTContext &C);
 
   /// Returns depobj expression associated with the clause.
   Expr *getDepobj() { return Depobj; }
   const Expr *getDepobj() const { return Depobj; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(&Depobj),
                        reinterpret_cast<Stmt **>(&Depobj) + 1);
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPDepobjClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_depobj;
   }
 };
 
 /// This represents implicit clause 'depend' for the '#pragma omp task'
 /// directive.
 ///
 /// \code
 /// #pragma omp task depend(in:a,b)
 /// \endcode
 /// In this example directive '#pragma omp task' with clause 'depend' with the
 /// variables 'a' and 'b' with dependency 'in'.
 class OMPDependClause final
     : public OMPVarListClause<OMPDependClause>,
       private llvm::TrailingObjects<OMPDependClause, Expr *> {
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Dependency type (one of in, out, inout).
   OpenMPDependClauseKind DepKind = OMPC_DEPEND_unknown;
 
   /// Dependency type location.
   SourceLocation DepLoc;
 
   /// Colon location.
   SourceLocation ColonLoc;
 
   /// Number of loops, associated with the depend clause.
   unsigned NumLoops = 0;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param N Number of the variables in the clause.
   /// \param NumLoops Number of loops that is associated with this depend
   /// clause.
   OMPDependClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                   SourceLocation EndLoc, unsigned N, unsigned NumLoops)
       : OMPVarListClause<OMPDependClause>(OMPC_depend, StartLoc, LParenLoc,
                                           EndLoc, N), NumLoops(NumLoops) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   /// \param NumLoops Number of loops that is associated with this depend
   /// clause.
   explicit OMPDependClause(unsigned N, unsigned NumLoops)
       : OMPVarListClause<OMPDependClause>(OMPC_depend, SourceLocation(),
                                           SourceLocation(), SourceLocation(),
                                           N),
         NumLoops(NumLoops) {}
 
   /// Set dependency kind.
   void setDependencyKind(OpenMPDependClauseKind K) { DepKind = K; }
 
   /// Set dependency kind and its location.
   void setDependencyLoc(SourceLocation Loc) { DepLoc = Loc; }
 
   /// Set colon location.
   void setColonLoc(SourceLocation Loc) { ColonLoc = Loc; }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param DepKind Dependency type.
   /// \param DepLoc Location of the dependency type.
   /// \param ColonLoc Colon location.
   /// \param VL List of references to the variables.
   /// \param NumLoops Number of loops that is associated with this depend
   /// clause.
   static OMPDependClause *Create(const ASTContext &C, SourceLocation StartLoc,
                                  SourceLocation LParenLoc,
                                  SourceLocation EndLoc,
                                  OpenMPDependClauseKind DepKind,
                                  SourceLocation DepLoc, SourceLocation ColonLoc,
                                  ArrayRef<Expr *> VL, unsigned NumLoops);
 
   /// Creates an empty clause with \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   /// \param NumLoops Number of loops that is associated with this depend
   /// clause.
   static OMPDependClause *CreateEmpty(const ASTContext &C, unsigned N,
                                       unsigned NumLoops);
 
   /// Get dependency type.
   OpenMPDependClauseKind getDependencyKind() const { return DepKind; }
 
   /// Get dependency type location.
   SourceLocation getDependencyLoc() const { return DepLoc; }
 
   /// Get colon location.
   SourceLocation getColonLoc() const { return ColonLoc; }
 
   /// Get number of loops associated with the clause.
   unsigned getNumLoops() const { return NumLoops; }
 
   /// Set the loop data for the depend clauses with 'sink|source' kind of
   /// dependency.
   void setLoopData(unsigned NumLoop, Expr *Cnt);
 
   /// Get the loop data.
   Expr *getLoopData(unsigned NumLoop);
   const Expr *getLoopData(unsigned NumLoop) const;
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPDependClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_depend;
   }
 };
 
 /// This represents 'device' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp target device(a)
 /// \endcode
 /// In this example directive '#pragma omp target' has clause 'device'
 /// with single expression 'a'.
 class OMPDeviceClause : public OMPClause, public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
+  /// Device clause modifier.
+  OpenMPDeviceClauseModifier Modifier = OMPC_DEVICE_unknown;
+
+  /// Location of the modifier.
+  SourceLocation ModifierLoc;
+
   /// Device number.
   Stmt *Device = nullptr;
 
   /// Set the device number.
   ///
   /// \param E Device number.
   void setDevice(Expr *E) { Device = E; }
 
+  /// Sets modifier.
+  void setModifier(OpenMPDeviceClauseModifier M) { Modifier = M; }
+
+  /// Setst modifier location.
+  void setModifierLoc(SourceLocation Loc) { ModifierLoc = Loc; }
+
 public:
   /// Build 'device' clause.
   ///
+  /// \param Modifier Clause modifier.
   /// \param E Expression associated with this clause.
   /// \param CaptureRegion Innermost OpenMP region where expressions in this
   /// clause must be captured.
   /// \param StartLoc Starting location of the clause.
+  /// \param ModifierLoc Modifier location.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
-  OMPDeviceClause(Expr *E, Stmt *HelperE, OpenMPDirectiveKind CaptureRegion,
-                  SourceLocation StartLoc, SourceLocation LParenLoc,
+  OMPDeviceClause(OpenMPDeviceClauseModifier Modifier, Expr *E, Stmt *HelperE,
+                  OpenMPDirectiveKind CaptureRegion, SourceLocation StartLoc,
+                  SourceLocation LParenLoc, SourceLocation ModifierLoc,
                   SourceLocation EndLoc)
       : OMPClause(OMPC_device, StartLoc, EndLoc), OMPClauseWithPreInit(this),
-        LParenLoc(LParenLoc), Device(E) {
+        LParenLoc(LParenLoc), Modifier(Modifier), ModifierLoc(ModifierLoc),
+        Device(E) {
     setPreInitStmt(HelperE, CaptureRegion);
   }
 
   /// Build an empty clause.
   OMPDeviceClause()
       : OMPClause(OMPC_device, SourceLocation(), SourceLocation()),
         OMPClauseWithPreInit(this) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Return device number.
   Expr *getDevice() { return cast<Expr>(Device); }
 
   /// Return device number.
   Expr *getDevice() const { return cast<Expr>(Device); }
 
+  /// Gets modifier.
+  OpenMPDeviceClauseModifier getModifier() const { return Modifier; }
+
+  /// Gets modifier location.
+  SourceLocation getModifierLoc() const { return ModifierLoc; }
+
   child_range children() { return child_range(&Device, &Device + 1); }
 
   const_child_range children() const {
     return const_child_range(&Device, &Device + 1);
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_device;
   }
 };
 
 /// This represents 'threads' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp ordered threads
 /// \endcode
 /// In this example directive '#pragma omp ordered' has simple 'threads' clause.
 class OMPThreadsClause : public OMPClause {
 public:
   /// Build 'threads' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPThreadsClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_threads, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPThreadsClause()
       : OMPClause(OMPC_threads, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_threads;
   }
 };
 
 /// This represents 'simd' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp ordered simd
 /// \endcode
 /// In this example directive '#pragma omp ordered' has simple 'simd' clause.
 class OMPSIMDClause : public OMPClause {
 public:
   /// Build 'simd' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPSIMDClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_simd, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPSIMDClause() : OMPClause(OMPC_simd, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_simd;
   }
 };
 
 /// Struct that defines common infrastructure to handle mappable
 /// expressions used in OpenMP clauses.
 class OMPClauseMappableExprCommon {
 public:
   /// Class that represents a component of a mappable expression. E.g.
   /// for an expression S.a, the first component is a declaration reference
   /// expression associated with 'S' and the second is a member expression
   /// associated with the field declaration 'a'. If the expression is an array
   /// subscript it may not have any associated declaration. In that case the
   /// associated declaration is set to nullptr.
   class MappableComponent {
     /// Expression associated with the component.
     Expr *AssociatedExpression = nullptr;
 
     /// Declaration associated with the declaration. If the component does
     /// not have a declaration (e.g. array subscripts or section), this is set
     /// to nullptr.
     ValueDecl *AssociatedDeclaration = nullptr;
 
   public:
     explicit MappableComponent() = default;
     explicit MappableComponent(Expr *AssociatedExpression,
                                ValueDecl *AssociatedDeclaration)
         : AssociatedExpression(AssociatedExpression),
           AssociatedDeclaration(
               AssociatedDeclaration
                   ? cast<ValueDecl>(AssociatedDeclaration->getCanonicalDecl())
                   : nullptr) {}
 
     Expr *getAssociatedExpression() const { return AssociatedExpression; }
 
     ValueDecl *getAssociatedDeclaration() const {
       return AssociatedDeclaration;
     }
   };
 
   // List of components of an expression. This first one is the whole
   // expression and the last one is the base expression.
   using MappableExprComponentList = SmallVector<MappableComponent, 8>;
   using MappableExprComponentListRef = ArrayRef<MappableComponent>;
 
   // List of all component lists associated to the same base declaration.
   // E.g. if both 'S.a' and 'S.b' are a mappable expressions, each will have
   // their component list but the same base declaration 'S'.
   using MappableExprComponentLists = SmallVector<MappableExprComponentList, 8>;
   using MappableExprComponentListsRef = ArrayRef<MappableExprComponentList>;
 
 protected:
   // Return the total number of elements in a list of component lists.
   static unsigned
   getComponentsTotalNumber(MappableExprComponentListsRef ComponentLists);
 
   // Return the total number of elements in a list of declarations. All
   // declarations are expected to be canonical.
   static unsigned
   getUniqueDeclarationsTotalNumber(ArrayRef<const ValueDecl *> Declarations);
 };
 
 /// This structure contains all sizes needed for by an
 /// OMPMappableExprListClause.
 struct OMPMappableExprListSizeTy {
   /// Number of expressions listed.
   unsigned NumVars;
   /// Number of unique base declarations.
   unsigned NumUniqueDeclarations;
   /// Number of component lists.
   unsigned NumComponentLists;
   /// Total number of expression components.
   unsigned NumComponents;
   OMPMappableExprListSizeTy() = default;
   OMPMappableExprListSizeTy(unsigned NumVars, unsigned NumUniqueDeclarations,
                             unsigned NumComponentLists, unsigned NumComponents)
       : NumVars(NumVars), NumUniqueDeclarations(NumUniqueDeclarations),
         NumComponentLists(NumComponentLists), NumComponents(NumComponents) {}
 };
 
 /// This represents clauses with a list of expressions that are mappable.
 /// Examples of these clauses are 'map' in
 /// '#pragma omp target [enter|exit] [data]...' directives, and  'to' and 'from
 /// in '#pragma omp target update...' directives.
 template <class T>
 class OMPMappableExprListClause : public OMPVarListClause<T>,
                                   public OMPClauseMappableExprCommon {
   friend class OMPClauseReader;
 
   /// Number of unique declarations in this clause.
   unsigned NumUniqueDeclarations;
 
   /// Number of component lists in this clause.
   unsigned NumComponentLists;
 
   /// Total number of components in this clause.
   unsigned NumComponents;
 
   /// C++ nested name specifier for the associated user-defined mapper.
   NestedNameSpecifierLoc MapperQualifierLoc;
 
   /// The associated user-defined mapper identifier information.
   DeclarationNameInfo MapperIdInfo;
 
 protected:
   /// Build a clause for \a NumUniqueDeclarations declarations, \a
   /// NumComponentLists total component lists, and \a NumComponents total
   /// components.
   ///
   /// \param K Kind of the clause.
   /// \param Locs Locations needed to build a mappable clause. It includes 1)
   /// StartLoc: starting location of the clause (the clause keyword); 2)
   /// LParenLoc: location of '('; 3) EndLoc: ending location of the clause.
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   /// \param MapperQualifierLocPtr C++ nested name specifier for the associated
   /// user-defined mapper.
   /// \param MapperIdInfoPtr The identifier of associated user-defined mapper.
   OMPMappableExprListClause(
       OpenMPClauseKind K, const OMPVarListLocTy &Locs,
       const OMPMappableExprListSizeTy &Sizes,
       NestedNameSpecifierLoc *MapperQualifierLocPtr = nullptr,
       DeclarationNameInfo *MapperIdInfoPtr = nullptr)
       : OMPVarListClause<T>(K, Locs.StartLoc, Locs.LParenLoc, Locs.EndLoc,
                             Sizes.NumVars),
         NumUniqueDeclarations(Sizes.NumUniqueDeclarations),
         NumComponentLists(Sizes.NumComponentLists),
         NumComponents(Sizes.NumComponents) {
     if (MapperQualifierLocPtr)
       MapperQualifierLoc = *MapperQualifierLocPtr;
     if (MapperIdInfoPtr)
       MapperIdInfo = *MapperIdInfoPtr;
   }
 
   /// Get the unique declarations that are in the trailing objects of the
   /// class.
   MutableArrayRef<ValueDecl *> getUniqueDeclsRef() {
     return MutableArrayRef<ValueDecl *>(
         static_cast<T *>(this)->template getTrailingObjects<ValueDecl *>(),
         NumUniqueDeclarations);
   }
 
   /// Get the unique declarations that are in the trailing objects of the
   /// class.
   ArrayRef<ValueDecl *> getUniqueDeclsRef() const {
     return ArrayRef<ValueDecl *>(
         static_cast<const T *>(this)
             ->template getTrailingObjects<ValueDecl *>(),
         NumUniqueDeclarations);
   }
 
   /// Set the unique declarations that are in the trailing objects of the
   /// class.
   void setUniqueDecls(ArrayRef<ValueDecl *> UDs) {
     assert(UDs.size() == NumUniqueDeclarations &&
            "Unexpected amount of unique declarations.");
     std::copy(UDs.begin(), UDs.end(), getUniqueDeclsRef().begin());
   }
 
   /// Get the number of lists per declaration that are in the trailing
   /// objects of the class.
   MutableArrayRef<unsigned> getDeclNumListsRef() {
     return MutableArrayRef<unsigned>(
         static_cast<T *>(this)->template getTrailingObjects<unsigned>(),
         NumUniqueDeclarations);
   }
 
   /// Get the number of lists per declaration that are in the trailing
   /// objects of the class.
   ArrayRef<unsigned> getDeclNumListsRef() const {
     return ArrayRef<unsigned>(
         static_cast<const T *>(this)->template getTrailingObjects<unsigned>(),
         NumUniqueDeclarations);
   }
 
   /// Set the number of lists per declaration that are in the trailing
   /// objects of the class.
   void setDeclNumLists(ArrayRef<unsigned> DNLs) {
     assert(DNLs.size() == NumUniqueDeclarations &&
            "Unexpected amount of list numbers.");
     std::copy(DNLs.begin(), DNLs.end(), getDeclNumListsRef().begin());
   }
 
   /// Get the cumulative component lists sizes that are in the trailing
   /// objects of the class. They are appended after the number of lists.
   MutableArrayRef<unsigned> getComponentListSizesRef() {
     return MutableArrayRef<unsigned>(
         static_cast<T *>(this)->template getTrailingObjects<unsigned>() +
             NumUniqueDeclarations,
         NumComponentLists);
   }
 
   /// Get the cumulative component lists sizes that are in the trailing
   /// objects of the class. They are appended after the number of lists.
   ArrayRef<unsigned> getComponentListSizesRef() const {
     return ArrayRef<unsigned>(
         static_cast<const T *>(this)->template getTrailingObjects<unsigned>() +
             NumUniqueDeclarations,
         NumComponentLists);
   }
 
   /// Set the cumulative component lists sizes that are in the trailing
   /// objects of the class.
   void setComponentListSizes(ArrayRef<unsigned> CLSs) {
     assert(CLSs.size() == NumComponentLists &&
            "Unexpected amount of component lists.");
     std::copy(CLSs.begin(), CLSs.end(), getComponentListSizesRef().begin());
   }
 
   /// Get the components that are in the trailing objects of the class.
   MutableArrayRef<MappableComponent> getComponentsRef() {
     return MutableArrayRef<MappableComponent>(
         static_cast<T *>(this)
             ->template getTrailingObjects<MappableComponent>(),
         NumComponents);
   }
 
   /// Get the components that are in the trailing objects of the class.
   ArrayRef<MappableComponent> getComponentsRef() const {
     return ArrayRef<MappableComponent>(
         static_cast<const T *>(this)
             ->template getTrailingObjects<MappableComponent>(),
         NumComponents);
   }
 
   /// Set the components that are in the trailing objects of the class.
   /// This requires the list sizes so that it can also fill the original
   /// expressions, which are the first component of each list.
   void setComponents(ArrayRef<MappableComponent> Components,
                      ArrayRef<unsigned> CLSs) {
     assert(Components.size() == NumComponents &&
            "Unexpected amount of component lists.");
     assert(CLSs.size() == NumComponentLists &&
            "Unexpected amount of list sizes.");
     std::copy(Components.begin(), Components.end(), getComponentsRef().begin());
   }
 
   /// Fill the clause information from the list of declarations and
   /// associated component lists.
   void setClauseInfo(ArrayRef<ValueDecl *> Declarations,
                      MappableExprComponentListsRef ComponentLists) {
     // Perform some checks to make sure the data sizes are consistent with the
     // information available when the clause was created.
     assert(getUniqueDeclarationsTotalNumber(Declarations) ==
                NumUniqueDeclarations &&
            "Unexpected number of mappable expression info entries!");
     assert(getComponentsTotalNumber(ComponentLists) == NumComponents &&
            "Unexpected total number of components!");
     assert(Declarations.size() == ComponentLists.size() &&
            "Declaration and component lists size is not consistent!");
     assert(Declarations.size() == NumComponentLists &&
            "Unexpected declaration and component lists size!");
 
     // Organize the components by declaration and retrieve the original
     // expression. Original expressions are always the first component of the
     // mappable component list.
     llvm::MapVector<ValueDecl *, SmallVector<MappableExprComponentListRef, 8>>
         ComponentListMap;
     {
       auto CI = ComponentLists.begin();
       for (auto DI = Declarations.begin(), DE = Declarations.end(); DI != DE;
            ++DI, ++CI) {
         assert(!CI->empty() && "Invalid component list!");
         ComponentListMap[*DI].push_back(*CI);
       }
     }
 
     // Iterators of the target storage.
     auto UniqueDeclarations = getUniqueDeclsRef();
     auto UDI = UniqueDeclarations.begin();
 
     auto DeclNumLists = getDeclNumListsRef();
     auto DNLI = DeclNumLists.begin();
 
     auto ComponentListSizes = getComponentListSizesRef();
     auto CLSI = ComponentListSizes.begin();
 
     auto Components = getComponentsRef();
     auto CI = Components.begin();
 
     // Variable to compute the accumulation of the number of components.
     unsigned PrevSize = 0u;
 
     // Scan all the declarations and associated component lists.
     for (auto &M : ComponentListMap) {
       // The declaration.
       auto *D = M.first;
       // The component lists.
       auto CL = M.second;
 
       // Initialize the entry.
       *UDI = D;
       ++UDI;
 
       *DNLI = CL.size();
       ++DNLI;
 
       // Obtain the cumulative sizes and concatenate all the components in the
       // reserved storage.
       for (auto C : CL) {
         // Accumulate with the previous size.
         PrevSize += C.size();
 
         // Save the size.
         *CLSI = PrevSize;
         ++CLSI;
 
         // Append components after the current components iterator.
         CI = std::copy(C.begin(), C.end(), CI);
       }
     }
   }
 
   /// Set the nested name specifier of associated user-defined mapper.
   void setMapperQualifierLoc(NestedNameSpecifierLoc NNSL) {
     MapperQualifierLoc = NNSL;
   }
 
   /// Set the name of associated user-defined mapper.
   void setMapperIdInfo(DeclarationNameInfo MapperId) {
     MapperIdInfo = MapperId;
   }
 
   /// Get the user-defined mapper references that are in the trailing objects of
   /// the class.
   MutableArrayRef<Expr *> getUDMapperRefs() {
     return llvm::makeMutableArrayRef<Expr *>(
         static_cast<T *>(this)->template getTrailingObjects<Expr *>() +
             OMPVarListClause<T>::varlist_size(),
         OMPVarListClause<T>::varlist_size());
   }
 
   /// Get the user-defined mappers references that are in the trailing objects
   /// of the class.
   ArrayRef<Expr *> getUDMapperRefs() const {
     return llvm::makeArrayRef<Expr *>(
         static_cast<T *>(this)->template getTrailingObjects<Expr *>() +
             OMPVarListClause<T>::varlist_size(),
         OMPVarListClause<T>::varlist_size());
   }
 
   /// Set the user-defined mappers that are in the trailing objects of the
   /// class.
   void setUDMapperRefs(ArrayRef<Expr *> DMDs) {
     assert(DMDs.size() == OMPVarListClause<T>::varlist_size() &&
            "Unexpected number of user-defined mappers.");
     std::copy(DMDs.begin(), DMDs.end(), getUDMapperRefs().begin());
   }
 
 public:
   /// Return the number of unique base declarations in this clause.
   unsigned getUniqueDeclarationsNum() const { return NumUniqueDeclarations; }
 
   /// Return the number of lists derived from the clause expressions.
   unsigned getTotalComponentListNum() const { return NumComponentLists; }
 
   /// Return the total number of components in all lists derived from the
   /// clause.
   unsigned getTotalComponentsNum() const { return NumComponents; }
 
   /// Gets the nested name specifier for associated user-defined mapper.
   NestedNameSpecifierLoc getMapperQualifierLoc() const {
     return MapperQualifierLoc;
   }
 
   /// Gets the name info for associated user-defined mapper.
   const DeclarationNameInfo &getMapperIdInfo() const { return MapperIdInfo; }
 
   /// Iterator that browse the components by lists. It also allows
   /// browsing components of a single declaration.
   class const_component_lists_iterator
       : public llvm::iterator_adaptor_base<
             const_component_lists_iterator,
             MappableExprComponentListRef::const_iterator,
             std::forward_iterator_tag, MappableComponent, ptrdiff_t,
             MappableComponent, MappableComponent> {
     // The declaration the iterator currently refers to.
     ArrayRef<ValueDecl *>::iterator DeclCur;
 
     // The list number associated with the current declaration.
     ArrayRef<unsigned>::iterator NumListsCur;
 
     // Remaining lists for the current declaration.
     unsigned RemainingLists = 0;
 
     // The cumulative size of the previous list, or zero if there is no previous
     // list.
     unsigned PrevListSize = 0;
 
     // The cumulative sizes of the current list - it will delimit the remaining
     // range of interest.
     ArrayRef<unsigned>::const_iterator ListSizeCur;
     ArrayRef<unsigned>::const_iterator ListSizeEnd;
 
     // Iterator to the end of the components storage.
     MappableExprComponentListRef::const_iterator End;
 
   public:
     /// Construct an iterator that scans all lists.
     explicit const_component_lists_iterator(
         ArrayRef<ValueDecl *> UniqueDecls, ArrayRef<unsigned> DeclsListNum,
         ArrayRef<unsigned> CumulativeListSizes,
         MappableExprComponentListRef Components)
         : const_component_lists_iterator::iterator_adaptor_base(
               Components.begin()),
           DeclCur(UniqueDecls.begin()), NumListsCur(DeclsListNum.begin()),
           ListSizeCur(CumulativeListSizes.begin()),
           ListSizeEnd(CumulativeListSizes.end()), End(Components.end()) {
       assert(UniqueDecls.size() == DeclsListNum.size() &&
              "Inconsistent number of declarations and list sizes!");
       if (!DeclsListNum.empty())
         RemainingLists = *NumListsCur;
     }
 
     /// Construct an iterator that scan lists for a given declaration \a
     /// Declaration.
     explicit const_component_lists_iterator(
         const ValueDecl *Declaration, ArrayRef<ValueDecl *> UniqueDecls,
         ArrayRef<unsigned> DeclsListNum, ArrayRef<unsigned> CumulativeListSizes,
         MappableExprComponentListRef Components)
         : const_component_lists_iterator(UniqueDecls, DeclsListNum,
                                          CumulativeListSizes, Components) {
       // Look for the desired declaration. While we are looking for it, we
       // update the state so that we know the component where a given list
       // starts.
       for (; DeclCur != UniqueDecls.end(); ++DeclCur, ++NumListsCur) {
         if (*DeclCur == Declaration)
           break;
 
         assert(*NumListsCur > 0 && "No lists associated with declaration??");
 
         // Skip the lists associated with the current declaration, but save the
         // last list size that was skipped.
         std::advance(ListSizeCur, *NumListsCur - 1);
         PrevListSize = *ListSizeCur;
         ++ListSizeCur;
       }
 
       // If we didn't find any declaration, advance the iterator to after the
       // last component and set remaining lists to zero.
       if (ListSizeCur == CumulativeListSizes.end()) {
         this->I = End;
         RemainingLists = 0u;
         return;
       }
 
       // Set the remaining lists with the total number of lists of the current
       // declaration.
       RemainingLists = *NumListsCur;
 
       // Adjust the list size end iterator to the end of the relevant range.
       ListSizeEnd = ListSizeCur;
       std::advance(ListSizeEnd, RemainingLists);
 
       // Given that the list sizes are cumulative, the index of the component
       // that start the list is the size of the previous list.
       std::advance(this->I, PrevListSize);
     }
 
     // Return the array with the current list. The sizes are cumulative, so the
     // array size is the difference between the current size and previous one.
     std::pair<const ValueDecl *, MappableExprComponentListRef>
     operator*() const {
       assert(ListSizeCur != ListSizeEnd && "Invalid iterator!");
       return std::make_pair(
           *DeclCur,
           MappableExprComponentListRef(&*this->I, *ListSizeCur - PrevListSize));
     }
     std::pair<const ValueDecl *, MappableExprComponentListRef>
     operator->() const {
       return **this;
     }
 
     // Skip the components of the current list.
     const_component_lists_iterator &operator++() {
       assert(ListSizeCur != ListSizeEnd && RemainingLists &&
              "Invalid iterator!");
 
       // If we don't have more lists just skip all the components. Otherwise,
       // advance the iterator by the number of components in the current list.
       if (std::next(ListSizeCur) == ListSizeEnd) {
         this->I = End;
         RemainingLists = 0;
       } else {
         std::advance(this->I, *ListSizeCur - PrevListSize);
         PrevListSize = *ListSizeCur;
 
         // We are done with a declaration, move to the next one.
         if (!(--RemainingLists)) {
           ++DeclCur;
           ++NumListsCur;
           RemainingLists = *NumListsCur;
           assert(RemainingLists && "No lists in the following declaration??");
         }
       }
 
       ++ListSizeCur;
       return *this;
     }
   };
 
   using const_component_lists_range =
       llvm::iterator_range<const_component_lists_iterator>;
 
   /// Iterators for all component lists.
   const_component_lists_iterator component_lists_begin() const {
     return const_component_lists_iterator(
         getUniqueDeclsRef(), getDeclNumListsRef(), getComponentListSizesRef(),
         getComponentsRef());
   }
   const_component_lists_iterator component_lists_end() const {
     return const_component_lists_iterator(
         ArrayRef<ValueDecl *>(), ArrayRef<unsigned>(), ArrayRef<unsigned>(),
         MappableExprComponentListRef(getComponentsRef().end(),
                                      getComponentsRef().end()));
   }
   const_component_lists_range component_lists() const {
     return {component_lists_begin(), component_lists_end()};
   }
 
   /// Iterators for component lists associated with the provided
   /// declaration.
   const_component_lists_iterator
   decl_component_lists_begin(const ValueDecl *VD) const {
     return const_component_lists_iterator(
         VD, getUniqueDeclsRef(), getDeclNumListsRef(),
         getComponentListSizesRef(), getComponentsRef());
   }
   const_component_lists_iterator decl_component_lists_end() const {
     return component_lists_end();
   }
   const_component_lists_range decl_component_lists(const ValueDecl *VD) const {
     return {decl_component_lists_begin(VD), decl_component_lists_end()};
   }
 
   /// Iterators to access all the declarations, number of lists, list sizes, and
   /// components.
   using const_all_decls_iterator = ArrayRef<ValueDecl *>::iterator;
   using const_all_decls_range = llvm::iterator_range<const_all_decls_iterator>;
 
   const_all_decls_range all_decls() const {
     auto A = getUniqueDeclsRef();
     return const_all_decls_range(A.begin(), A.end());
   }
 
   using const_all_num_lists_iterator = ArrayRef<unsigned>::iterator;
   using const_all_num_lists_range =
       llvm::iterator_range<const_all_num_lists_iterator>;
 
   const_all_num_lists_range all_num_lists() const {
     auto A = getDeclNumListsRef();
     return const_all_num_lists_range(A.begin(), A.end());
   }
 
   using const_all_lists_sizes_iterator = ArrayRef<unsigned>::iterator;
   using const_all_lists_sizes_range =
       llvm::iterator_range<const_all_lists_sizes_iterator>;
 
   const_all_lists_sizes_range all_lists_sizes() const {
     auto A = getComponentListSizesRef();
     return const_all_lists_sizes_range(A.begin(), A.end());
   }
 
   using const_all_components_iterator = ArrayRef<MappableComponent>::iterator;
   using const_all_components_range =
       llvm::iterator_range<const_all_components_iterator>;
 
   const_all_components_range all_components() const {
     auto A = getComponentsRef();
     return const_all_components_range(A.begin(), A.end());
   }
 
   using mapperlist_iterator = MutableArrayRef<Expr *>::iterator;
   using mapperlist_const_iterator = ArrayRef<const Expr *>::iterator;
   using mapperlist_range = llvm::iterator_range<mapperlist_iterator>;
   using mapperlist_const_range =
       llvm::iterator_range<mapperlist_const_iterator>;
 
   mapperlist_iterator mapperlist_begin() { return getUDMapperRefs().begin(); }
   mapperlist_iterator mapperlist_end() { return getUDMapperRefs().end(); }
   mapperlist_const_iterator mapperlist_begin() const {
     return getUDMapperRefs().begin();
   }
   mapperlist_const_iterator mapperlist_end() const {
     return getUDMapperRefs().end();
   }
   mapperlist_range mapperlists() {
     return mapperlist_range(mapperlist_begin(), mapperlist_end());
   }
   mapperlist_const_range mapperlists() const {
     return mapperlist_const_range(mapperlist_begin(), mapperlist_end());
   }
 };
 
 /// This represents clause 'map' in the '#pragma omp ...'
 /// directives.
 ///
 /// \code
 /// #pragma omp target map(a,b)
 /// \endcode
 /// In this example directive '#pragma omp target' has clause 'map'
 /// with the variables 'a' and 'b'.
 class OMPMapClause final : public OMPMappableExprListClause<OMPMapClause>,
                            private llvm::TrailingObjects<
                                OMPMapClause, Expr *, ValueDecl *, unsigned,
                                OMPClauseMappableExprCommon::MappableComponent> {
   friend class OMPClauseReader;
   friend OMPMappableExprListClause;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Define the sizes of each trailing object array except the last one. This
   /// is required for TrailingObjects to work properly.
   size_t numTrailingObjects(OverloadToken<Expr *>) const {
     // There are varlist_size() of expressions, and varlist_size() of
     // user-defined mappers.
     return 2 * varlist_size();
   }
   size_t numTrailingObjects(OverloadToken<ValueDecl *>) const {
     return getUniqueDeclarationsNum();
   }
   size_t numTrailingObjects(OverloadToken<unsigned>) const {
     return getUniqueDeclarationsNum() + getTotalComponentListNum();
   }
 
 public:
   /// Number of allowed map-type-modifiers.
   static constexpr unsigned NumberOfModifiers =
       OMPC_MAP_MODIFIER_last - OMPC_MAP_MODIFIER_unknown - 1;
 
 private:
   /// Map-type-modifiers for the 'map' clause.
   OpenMPMapModifierKind MapTypeModifiers[NumberOfModifiers] = {
       OMPC_MAP_MODIFIER_unknown, OMPC_MAP_MODIFIER_unknown,
       OMPC_MAP_MODIFIER_unknown};
 
   /// Location of map-type-modifiers for the 'map' clause.
   SourceLocation MapTypeModifiersLoc[NumberOfModifiers];
 
   /// Map type for the 'map' clause.
   OpenMPMapClauseKind MapType = OMPC_MAP_unknown;
 
   /// Is this an implicit map type or not.
   bool MapTypeIsImplicit = false;
 
   /// Location of the map type.
   SourceLocation MapLoc;
 
   /// Colon location.
   SourceLocation ColonLoc;
 
   /// Build a clause for \a NumVars listed expressions, \a
   /// NumUniqueDeclarations declarations, \a NumComponentLists total component
   /// lists, and \a NumComponents total expression components.
   ///
   /// \param MapModifiers Map-type-modifiers.
   /// \param MapModifiersLoc Locations of map-type-modifiers.
   /// \param MapperQualifierLoc C++ nested name specifier for the associated
   /// user-defined mapper.
   /// \param MapperIdInfo The identifier of associated user-defined mapper.
   /// \param MapType Map type.
   /// \param MapTypeIsImplicit Map type is inferred implicitly.
   /// \param MapLoc Location of the map type.
   /// \param Locs Locations needed to build a mappable clause. It includes 1)
   /// StartLoc: starting location of the clause (the clause keyword); 2)
   /// LParenLoc: location of '('; 3) EndLoc: ending location of the clause.
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   explicit OMPMapClause(ArrayRef<OpenMPMapModifierKind> MapModifiers,
                         ArrayRef<SourceLocation> MapModifiersLoc,
                         NestedNameSpecifierLoc MapperQualifierLoc,
                         DeclarationNameInfo MapperIdInfo,
                         OpenMPMapClauseKind MapType, bool MapTypeIsImplicit,
                         SourceLocation MapLoc, const OMPVarListLocTy &Locs,
                         const OMPMappableExprListSizeTy &Sizes)
       : OMPMappableExprListClause(OMPC_map, Locs, Sizes, &MapperQualifierLoc,
                                   &MapperIdInfo),
         MapType(MapType), MapTypeIsImplicit(MapTypeIsImplicit), MapLoc(MapLoc) {
     assert(llvm::array_lengthof(MapTypeModifiers) == MapModifiers.size() &&
            "Unexpected number of map type modifiers.");
     llvm::copy(MapModifiers, std::begin(MapTypeModifiers));
 
     assert(llvm::array_lengthof(MapTypeModifiersLoc) ==
                MapModifiersLoc.size() &&
            "Unexpected number of map type modifier locations.");
     llvm::copy(MapModifiersLoc, std::begin(MapTypeModifiersLoc));
   }
 
   /// Build an empty clause.
   ///
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   explicit OMPMapClause(const OMPMappableExprListSizeTy &Sizes)
       : OMPMappableExprListClause(OMPC_map, OMPVarListLocTy(), Sizes) {}
 
   /// Set map-type-modifier for the clause.
   ///
   /// \param I index for map-type-modifier.
   /// \param T map-type-modifier for the clause.
   void setMapTypeModifier(unsigned I, OpenMPMapModifierKind T) {
     assert(I < NumberOfModifiers &&
            "Unexpected index to store map type modifier, exceeds array size.");
     MapTypeModifiers[I] = T;
   }
 
   /// Set location for the map-type-modifier.
   ///
   /// \param I index for map-type-modifier location.
   /// \param TLoc map-type-modifier location.
   void setMapTypeModifierLoc(unsigned I, SourceLocation TLoc) {
     assert(I < NumberOfModifiers &&
            "Index to store map type modifier location exceeds array size.");
     MapTypeModifiersLoc[I] = TLoc;
   }
 
   /// Set type for the clause.
   ///
   /// \param T Type for the clause.
   void setMapType(OpenMPMapClauseKind T) { MapType = T; }
 
   /// Set type location.
   ///
   /// \param TLoc Type location.
   void setMapLoc(SourceLocation TLoc) { MapLoc = TLoc; }
 
   /// Set colon location.
   void setColonLoc(SourceLocation Loc) { ColonLoc = Loc; }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param C AST context.
   /// \param Locs Locations needed to build a mappable clause. It includes 1)
   /// StartLoc: starting location of the clause (the clause keyword); 2)
   /// LParenLoc: location of '('; 3) EndLoc: ending location of the clause.
   /// \param Vars The original expression used in the clause.
   /// \param Declarations Declarations used in the clause.
   /// \param ComponentLists Component lists used in the clause.
   /// \param UDMapperRefs References to user-defined mappers associated with
   /// expressions used in the clause.
   /// \param MapModifiers Map-type-modifiers.
   /// \param MapModifiersLoc Location of map-type-modifiers.
   /// \param UDMQualifierLoc C++ nested name specifier for the associated
   /// user-defined mapper.
   /// \param MapperId The identifier of associated user-defined mapper.
   /// \param Type Map type.
   /// \param TypeIsImplicit Map type is inferred implicitly.
   /// \param TypeLoc Location of the map type.
   static OMPMapClause *
   Create(const ASTContext &C, const OMPVarListLocTy &Locs,
          ArrayRef<Expr *> Vars, ArrayRef<ValueDecl *> Declarations,
          MappableExprComponentListsRef ComponentLists,
          ArrayRef<Expr *> UDMapperRefs,
          ArrayRef<OpenMPMapModifierKind> MapModifiers,
          ArrayRef<SourceLocation> MapModifiersLoc,
          NestedNameSpecifierLoc UDMQualifierLoc, DeclarationNameInfo MapperId,
          OpenMPMapClauseKind Type, bool TypeIsImplicit, SourceLocation TypeLoc);
 
   /// Creates an empty clause with the place for \a NumVars original
   /// expressions, \a NumUniqueDeclarations declarations, \NumComponentLists
   /// lists, and \a NumComponents expression components.
   ///
   /// \param C AST context.
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   static OMPMapClause *CreateEmpty(const ASTContext &C,
                                    const OMPMappableExprListSizeTy &Sizes);
 
   /// Fetches mapping kind for the clause.
   OpenMPMapClauseKind getMapType() const LLVM_READONLY { return MapType; }
 
   /// Is this an implicit map type?
   /// We have to capture 'IsMapTypeImplicit' from the parser for more
   /// informative error messages.  It helps distinguish map(r) from
   /// map(tofrom: r), which is important to print more helpful error
   /// messages for some target directives.
   bool isImplicitMapType() const LLVM_READONLY { return MapTypeIsImplicit; }
 
   /// Fetches the map-type-modifier at 'Cnt' index of array of modifiers.
   ///
   /// \param Cnt index for map-type-modifier.
   OpenMPMapModifierKind getMapTypeModifier(unsigned Cnt) const LLVM_READONLY {
     assert(Cnt < NumberOfModifiers &&
            "Requested modifier exceeds the total number of modifiers.");
     return MapTypeModifiers[Cnt];
   }
 
   /// Fetches the map-type-modifier location at 'Cnt' index of array of
   /// modifiers' locations.
   ///
   /// \param Cnt index for map-type-modifier location.
   SourceLocation getMapTypeModifierLoc(unsigned Cnt) const LLVM_READONLY {
     assert(Cnt < NumberOfModifiers &&
            "Requested modifier location exceeds total number of modifiers.");
     return MapTypeModifiersLoc[Cnt];
   }
 
   /// Fetches ArrayRef of map-type-modifiers.
   ArrayRef<OpenMPMapModifierKind> getMapTypeModifiers() const LLVM_READONLY {
     return llvm::makeArrayRef(MapTypeModifiers);
   }
 
   /// Fetches ArrayRef of location of map-type-modifiers.
   ArrayRef<SourceLocation> getMapTypeModifiersLoc() const LLVM_READONLY {
     return llvm::makeArrayRef(MapTypeModifiersLoc);
   }
 
   /// Fetches location of clause mapping kind.
   SourceLocation getMapLoc() const LLVM_READONLY { return MapLoc; }
 
   /// Get colon location.
   SourceLocation getColonLoc() const { return ColonLoc; }
 
   child_range children() {
     return child_range(
         reinterpret_cast<Stmt **>(varlist_begin()),
         reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPMapClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     if (MapType == OMPC_MAP_to || MapType == OMPC_MAP_tofrom)
       return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                          reinterpret_cast<Stmt **>(varlist_end()));
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     auto Children = const_cast<OMPMapClause *>(this)->used_children();
     return const_child_range(Children.begin(), Children.end());
   }
 
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_map;
   }
 };
 
 /// This represents 'num_teams' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp teams num_teams(n)
 /// \endcode
 /// In this example directive '#pragma omp teams' has clause 'num_teams'
 /// with single expression 'n'.
 class OMPNumTeamsClause : public OMPClause, public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// NumTeams number.
   Stmt *NumTeams = nullptr;
 
   /// Set the NumTeams number.
   ///
   /// \param E NumTeams number.
   void setNumTeams(Expr *E) { NumTeams = E; }
 
 public:
   /// Build 'num_teams' clause.
   ///
   /// \param E Expression associated with this clause.
   /// \param HelperE Helper Expression associated with this clause.
   /// \param CaptureRegion Innermost OpenMP region where expressions in this
   /// clause must be captured.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPNumTeamsClause(Expr *E, Stmt *HelperE, OpenMPDirectiveKind CaptureRegion,
                     SourceLocation StartLoc, SourceLocation LParenLoc,
                     SourceLocation EndLoc)
       : OMPClause(OMPC_num_teams, StartLoc, EndLoc), OMPClauseWithPreInit(this),
         LParenLoc(LParenLoc), NumTeams(E) {
     setPreInitStmt(HelperE, CaptureRegion);
   }
 
   /// Build an empty clause.
   OMPNumTeamsClause()
       : OMPClause(OMPC_num_teams, SourceLocation(), SourceLocation()),
         OMPClauseWithPreInit(this) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Return NumTeams number.
   Expr *getNumTeams() { return cast<Expr>(NumTeams); }
 
   /// Return NumTeams number.
   Expr *getNumTeams() const { return cast<Expr>(NumTeams); }
 
   child_range children() { return child_range(&NumTeams, &NumTeams + 1); }
 
   const_child_range children() const {
     return const_child_range(&NumTeams, &NumTeams + 1);
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_num_teams;
   }
 };
 
 /// This represents 'thread_limit' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp teams thread_limit(n)
 /// \endcode
 /// In this example directive '#pragma omp teams' has clause 'thread_limit'
 /// with single expression 'n'.
 class OMPThreadLimitClause : public OMPClause, public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// ThreadLimit number.
   Stmt *ThreadLimit = nullptr;
 
   /// Set the ThreadLimit number.
   ///
   /// \param E ThreadLimit number.
   void setThreadLimit(Expr *E) { ThreadLimit = E; }
 
 public:
   /// Build 'thread_limit' clause.
   ///
   /// \param E Expression associated with this clause.
   /// \param HelperE Helper Expression associated with this clause.
   /// \param CaptureRegion Innermost OpenMP region where expressions in this
   /// clause must be captured.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPThreadLimitClause(Expr *E, Stmt *HelperE,
                        OpenMPDirectiveKind CaptureRegion,
                        SourceLocation StartLoc, SourceLocation LParenLoc,
                        SourceLocation EndLoc)
       : OMPClause(OMPC_thread_limit, StartLoc, EndLoc),
         OMPClauseWithPreInit(this), LParenLoc(LParenLoc), ThreadLimit(E) {
     setPreInitStmt(HelperE, CaptureRegion);
   }
 
   /// Build an empty clause.
   OMPThreadLimitClause()
       : OMPClause(OMPC_thread_limit, SourceLocation(), SourceLocation()),
         OMPClauseWithPreInit(this) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Return ThreadLimit number.
   Expr *getThreadLimit() { return cast<Expr>(ThreadLimit); }
 
   /// Return ThreadLimit number.
   Expr *getThreadLimit() const { return cast<Expr>(ThreadLimit); }
 
   child_range children() { return child_range(&ThreadLimit, &ThreadLimit + 1); }
 
   const_child_range children() const {
     return const_child_range(&ThreadLimit, &ThreadLimit + 1);
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_thread_limit;
   }
 };
 
 /// This represents 'priority' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp task priority(n)
 /// \endcode
 /// In this example directive '#pragma omp teams' has clause 'priority' with
 /// single expression 'n'.
 class OMPPriorityClause : public OMPClause, public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Priority number.
   Stmt *Priority = nullptr;
 
   /// Set the Priority number.
   ///
   /// \param E Priority number.
   void setPriority(Expr *E) { Priority = E; }
 
 public:
   /// Build 'priority' clause.
   ///
   /// \param Priority Expression associated with this clause.
   /// \param HelperPriority Helper priority for the construct.
   /// \param CaptureRegion Innermost OpenMP region where expressions in this
   /// clause must be captured.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPPriorityClause(Expr *Priority, Stmt *HelperPriority,
                     OpenMPDirectiveKind CaptureRegion, SourceLocation StartLoc,
                     SourceLocation LParenLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_priority, StartLoc, EndLoc), OMPClauseWithPreInit(this),
         LParenLoc(LParenLoc), Priority(Priority) {
     setPreInitStmt(HelperPriority, CaptureRegion);
   }
 
   /// Build an empty clause.
   OMPPriorityClause()
       : OMPClause(OMPC_priority, SourceLocation(), SourceLocation()),
         OMPClauseWithPreInit(this) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Return Priority number.
   Expr *getPriority() { return cast<Expr>(Priority); }
 
   /// Return Priority number.
   Expr *getPriority() const { return cast<Expr>(Priority); }
 
   child_range children() { return child_range(&Priority, &Priority + 1); }
 
   const_child_range children() const {
     return const_child_range(&Priority, &Priority + 1);
   }
 
   child_range used_children();
   const_child_range used_children() const {
     auto Children = const_cast<OMPPriorityClause *>(this)->used_children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_priority;
   }
 };
 
 /// This represents 'grainsize' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp taskloop grainsize(4)
 /// \endcode
 /// In this example directive '#pragma omp taskloop' has clause 'grainsize'
 /// with single expression '4'.
 class OMPGrainsizeClause : public OMPClause, public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Safe iteration space distance.
   Stmt *Grainsize = nullptr;
 
   /// Set safelen.
   void setGrainsize(Expr *Size) { Grainsize = Size; }
 
 public:
   /// Build 'grainsize' clause.
   ///
   /// \param Size Expression associated with this clause.
   /// \param HelperSize Helper grainsize for the construct.
   /// \param CaptureRegion Innermost OpenMP region where expressions in this
   /// clause must be captured.
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPGrainsizeClause(Expr *Size, Stmt *HelperSize,
                      OpenMPDirectiveKind CaptureRegion, SourceLocation StartLoc,
                      SourceLocation LParenLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_grainsize, StartLoc, EndLoc), OMPClauseWithPreInit(this),
         LParenLoc(LParenLoc), Grainsize(Size) {
     setPreInitStmt(HelperSize, CaptureRegion);
   }
 
   /// Build an empty clause.
   explicit OMPGrainsizeClause()
       : OMPClause(OMPC_grainsize, SourceLocation(), SourceLocation()),
         OMPClauseWithPreInit(this) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Return safe iteration space distance.
   Expr *getGrainsize() const { return cast_or_null<Expr>(Grainsize); }
 
   child_range children() { return child_range(&Grainsize, &Grainsize + 1); }
 
   const_child_range children() const {
     return const_child_range(&Grainsize, &Grainsize + 1);
   }
 
   child_range used_children();
   const_child_range used_children() const {
     auto Children = const_cast<OMPGrainsizeClause *>(this)->used_children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_grainsize;
   }
 };
 
 /// This represents 'nogroup' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp taskloop nogroup
 /// \endcode
 /// In this example directive '#pragma omp taskloop' has 'nogroup' clause.
 class OMPNogroupClause : public OMPClause {
 public:
   /// Build 'nogroup' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPNogroupClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_nogroup, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPNogroupClause()
       : OMPClause(OMPC_nogroup, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_nogroup;
   }
 };
 
 /// This represents 'num_tasks' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp taskloop num_tasks(4)
 /// \endcode
 /// In this example directive '#pragma omp taskloop' has clause 'num_tasks'
 /// with single expression '4'.
 class OMPNumTasksClause : public OMPClause, public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Safe iteration space distance.
   Stmt *NumTasks = nullptr;
 
   /// Set safelen.
   void setNumTasks(Expr *Size) { NumTasks = Size; }
 
 public:
   /// Build 'num_tasks' clause.
   ///
   /// \param Size Expression associated with this clause.
   /// \param HelperSize Helper grainsize for the construct.
   /// \param CaptureRegion Innermost OpenMP region where expressions in this
   /// clause must be captured.
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPNumTasksClause(Expr *Size, Stmt *HelperSize,
                     OpenMPDirectiveKind CaptureRegion, SourceLocation StartLoc,
                     SourceLocation LParenLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_num_tasks, StartLoc, EndLoc), OMPClauseWithPreInit(this),
         LParenLoc(LParenLoc), NumTasks(Size) {
     setPreInitStmt(HelperSize, CaptureRegion);
   }
 
   /// Build an empty clause.
   explicit OMPNumTasksClause()
       : OMPClause(OMPC_num_tasks, SourceLocation(), SourceLocation()),
         OMPClauseWithPreInit(this) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Return safe iteration space distance.
   Expr *getNumTasks() const { return cast_or_null<Expr>(NumTasks); }
 
   child_range children() { return child_range(&NumTasks, &NumTasks + 1); }
 
   const_child_range children() const {
     return const_child_range(&NumTasks, &NumTasks + 1);
   }
 
   child_range used_children();
   const_child_range used_children() const {
     auto Children = const_cast<OMPNumTasksClause *>(this)->used_children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_num_tasks;
   }
 };
 
 /// This represents 'hint' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp critical (name) hint(6)
 /// \endcode
 /// In this example directive '#pragma omp critical' has name 'name' and clause
 /// 'hint' with argument '6'.
 class OMPHintClause : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Hint expression of the 'hint' clause.
   Stmt *Hint = nullptr;
 
   /// Set hint expression.
   void setHint(Expr *H) { Hint = H; }
 
 public:
   /// Build 'hint' clause with expression \a Hint.
   ///
   /// \param Hint Hint expression.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPHintClause(Expr *Hint, SourceLocation StartLoc, SourceLocation LParenLoc,
                 SourceLocation EndLoc)
       : OMPClause(OMPC_hint, StartLoc, EndLoc), LParenLoc(LParenLoc),
         Hint(Hint) {}
 
   /// Build an empty clause.
   OMPHintClause() : OMPClause(OMPC_hint, SourceLocation(), SourceLocation()) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Returns number of threads.
   Expr *getHint() const { return cast_or_null<Expr>(Hint); }
 
   child_range children() { return child_range(&Hint, &Hint + 1); }
 
   const_child_range children() const {
     return const_child_range(&Hint, &Hint + 1);
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_hint;
   }
 };
 
 /// This represents 'dist_schedule' clause in the '#pragma omp ...'
 /// directive.
 ///
 /// \code
 /// #pragma omp distribute dist_schedule(static, 3)
 /// \endcode
 /// In this example directive '#pragma omp distribute' has 'dist_schedule'
 /// clause with arguments 'static' and '3'.
 class OMPDistScheduleClause : public OMPClause, public OMPClauseWithPreInit {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// A kind of the 'schedule' clause.
   OpenMPDistScheduleClauseKind Kind = OMPC_DIST_SCHEDULE_unknown;
 
   /// Start location of the schedule kind in source code.
   SourceLocation KindLoc;
 
   /// Location of ',' (if any).
   SourceLocation CommaLoc;
 
   /// Chunk size.
   Expr *ChunkSize = nullptr;
 
   /// Set schedule kind.
   ///
   /// \param K Schedule kind.
   void setDistScheduleKind(OpenMPDistScheduleClauseKind K) { Kind = K; }
 
   /// Sets the location of '('.
   ///
   /// \param Loc Location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Set schedule kind start location.
   ///
   /// \param KLoc Schedule kind location.
   void setDistScheduleKindLoc(SourceLocation KLoc) { KindLoc = KLoc; }
 
   /// Set location of ','.
   ///
   /// \param Loc Location of ','.
   void setCommaLoc(SourceLocation Loc) { CommaLoc = Loc; }
 
   /// Set chunk size.
   ///
   /// \param E Chunk size.
   void setChunkSize(Expr *E) { ChunkSize = E; }
 
 public:
   /// Build 'dist_schedule' clause with schedule kind \a Kind and chunk
   /// size expression \a ChunkSize.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param KLoc Starting location of the argument.
   /// \param CommaLoc Location of ','.
   /// \param EndLoc Ending location of the clause.
   /// \param Kind DistSchedule kind.
   /// \param ChunkSize Chunk size.
   /// \param HelperChunkSize Helper chunk size for combined directives.
   OMPDistScheduleClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                         SourceLocation KLoc, SourceLocation CommaLoc,
                         SourceLocation EndLoc,
                         OpenMPDistScheduleClauseKind Kind, Expr *ChunkSize,
                         Stmt *HelperChunkSize)
       : OMPClause(OMPC_dist_schedule, StartLoc, EndLoc),
         OMPClauseWithPreInit(this), LParenLoc(LParenLoc), Kind(Kind),
         KindLoc(KLoc), CommaLoc(CommaLoc), ChunkSize(ChunkSize) {
     setPreInitStmt(HelperChunkSize);
   }
 
   /// Build an empty clause.
   explicit OMPDistScheduleClause()
       : OMPClause(OMPC_dist_schedule, SourceLocation(), SourceLocation()),
         OMPClauseWithPreInit(this) {}
 
   /// Get kind of the clause.
   OpenMPDistScheduleClauseKind getDistScheduleKind() const { return Kind; }
 
   /// Get location of '('.
   SourceLocation getLParenLoc() { return LParenLoc; }
 
   /// Get kind location.
   SourceLocation getDistScheduleKindLoc() { return KindLoc; }
 
   /// Get location of ','.
   SourceLocation getCommaLoc() { return CommaLoc; }
 
   /// Get chunk size.
   Expr *getChunkSize() { return ChunkSize; }
 
   /// Get chunk size.
   const Expr *getChunkSize() const { return ChunkSize; }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(&ChunkSize),
                        reinterpret_cast<Stmt **>(&ChunkSize) + 1);
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPDistScheduleClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_dist_schedule;
   }
 };
 
 /// This represents 'defaultmap' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp target defaultmap(tofrom: scalar)
 /// \endcode
 /// In this example directive '#pragma omp target' has 'defaultmap' clause of kind
 /// 'scalar' with modifier 'tofrom'.
 class OMPDefaultmapClause : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Modifiers for 'defaultmap' clause.
   OpenMPDefaultmapClauseModifier Modifier = OMPC_DEFAULTMAP_MODIFIER_unknown;
 
   /// Locations of modifiers.
   SourceLocation ModifierLoc;
 
   /// A kind of the 'defaultmap' clause.
   OpenMPDefaultmapClauseKind Kind = OMPC_DEFAULTMAP_unknown;
 
   /// Start location of the defaultmap kind in source code.
   SourceLocation KindLoc;
 
   /// Set defaultmap kind.
   ///
   /// \param K Defaultmap kind.
   void setDefaultmapKind(OpenMPDefaultmapClauseKind K) { Kind = K; }
 
   /// Set the defaultmap modifier.
   ///
   /// \param M Defaultmap modifier.
   void setDefaultmapModifier(OpenMPDefaultmapClauseModifier M) {
     Modifier = M;
   }
 
   /// Set location of the defaultmap modifier.
   void setDefaultmapModifierLoc(SourceLocation Loc) {
     ModifierLoc = Loc;
   }
 
   /// Sets the location of '('.
   ///
   /// \param Loc Location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Set defaultmap kind start location.
   ///
   /// \param KLoc Defaultmap kind location.
   void setDefaultmapKindLoc(SourceLocation KLoc) { KindLoc = KLoc; }
 
 public:
   /// Build 'defaultmap' clause with defaultmap kind \a Kind
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param KLoc Starting location of the argument.
   /// \param EndLoc Ending location of the clause.
   /// \param Kind Defaultmap kind.
   /// \param M The modifier applied to 'defaultmap' clause.
   /// \param MLoc Location of the modifier
   OMPDefaultmapClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                       SourceLocation MLoc, SourceLocation KLoc,
                       SourceLocation EndLoc, OpenMPDefaultmapClauseKind Kind,
                       OpenMPDefaultmapClauseModifier M)
       : OMPClause(OMPC_defaultmap, StartLoc, EndLoc), LParenLoc(LParenLoc),
         Modifier(M), ModifierLoc(MLoc), Kind(Kind), KindLoc(KLoc) {}
 
   /// Build an empty clause.
   explicit OMPDefaultmapClause()
       : OMPClause(OMPC_defaultmap, SourceLocation(), SourceLocation()) {}
 
   /// Get kind of the clause.
   OpenMPDefaultmapClauseKind getDefaultmapKind() const { return Kind; }
 
   /// Get the modifier of the clause.
   OpenMPDefaultmapClauseModifier getDefaultmapModifier() const {
     return Modifier;
   }
 
   /// Get location of '('.
   SourceLocation getLParenLoc() { return LParenLoc; }
 
   /// Get kind location.
   SourceLocation getDefaultmapKindLoc() { return KindLoc; }
 
   /// Get the modifier location.
   SourceLocation getDefaultmapModifierLoc() const {
     return ModifierLoc;
   }
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_defaultmap;
   }
 };
 
 /// This represents clause 'to' in the '#pragma omp ...'
 /// directives.
 ///
 /// \code
 /// #pragma omp target update to(a,b)
 /// \endcode
 /// In this example directive '#pragma omp target update' has clause 'to'
 /// with the variables 'a' and 'b'.
 class OMPToClause final : public OMPMappableExprListClause<OMPToClause>,
                           private llvm::TrailingObjects<
                               OMPToClause, Expr *, ValueDecl *, unsigned,
                               OMPClauseMappableExprCommon::MappableComponent> {
   friend class OMPClauseReader;
   friend OMPMappableExprListClause;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Build clause with number of variables \a NumVars.
   ///
   /// \param MapperQualifierLoc C++ nested name specifier for the associated
   /// user-defined mapper.
   /// \param MapperIdInfo The identifier of associated user-defined mapper.
   /// \param Locs Locations needed to build a mappable clause. It includes 1)
   /// StartLoc: starting location of the clause (the clause keyword); 2)
   /// LParenLoc: location of '('; 3) EndLoc: ending location of the clause.
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   explicit OMPToClause(NestedNameSpecifierLoc MapperQualifierLoc,
                        DeclarationNameInfo MapperIdInfo,
                        const OMPVarListLocTy &Locs,
                        const OMPMappableExprListSizeTy &Sizes)
       : OMPMappableExprListClause(OMPC_to, Locs, Sizes, &MapperQualifierLoc,
                                   &MapperIdInfo) {}
 
   /// Build an empty clause.
   ///
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   explicit OMPToClause(const OMPMappableExprListSizeTy &Sizes)
       : OMPMappableExprListClause(OMPC_to, OMPVarListLocTy(), Sizes) {}
 
   /// Define the sizes of each trailing object array except the last one. This
   /// is required for TrailingObjects to work properly.
   size_t numTrailingObjects(OverloadToken<Expr *>) const {
     // There are varlist_size() of expressions, and varlist_size() of
     // user-defined mappers.
     return 2 * varlist_size();
   }
   size_t numTrailingObjects(OverloadToken<ValueDecl *>) const {
     return getUniqueDeclarationsNum();
   }
   size_t numTrailingObjects(OverloadToken<unsigned>) const {
     return getUniqueDeclarationsNum() + getTotalComponentListNum();
   }
 
 public:
   /// Creates clause with a list of variables \a Vars.
   ///
   /// \param C AST context.
   /// \param Locs Locations needed to build a mappable clause. It includes 1)
   /// StartLoc: starting location of the clause (the clause keyword); 2)
   /// LParenLoc: location of '('; 3) EndLoc: ending location of the clause.
   /// \param Vars The original expression used in the clause.
   /// \param Declarations Declarations used in the clause.
   /// \param ComponentLists Component lists used in the clause.
   /// \param UDMapperRefs References to user-defined mappers associated with
   /// expressions used in the clause.
   /// \param UDMQualifierLoc C++ nested name specifier for the associated
   /// user-defined mapper.
   /// \param MapperId The identifier of associated user-defined mapper.
   static OMPToClause *Create(const ASTContext &C, const OMPVarListLocTy &Locs,
                              ArrayRef<Expr *> Vars,
                              ArrayRef<ValueDecl *> Declarations,
                              MappableExprComponentListsRef ComponentLists,
                              ArrayRef<Expr *> UDMapperRefs,
                              NestedNameSpecifierLoc UDMQualifierLoc,
                              DeclarationNameInfo MapperId);
 
   /// Creates an empty clause with the place for \a NumVars variables.
   ///
   /// \param C AST context.
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   static OMPToClause *CreateEmpty(const ASTContext &C,
                                   const OMPMappableExprListSizeTy &Sizes);
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPToClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_to;
   }
 };
 
 /// This represents clause 'from' in the '#pragma omp ...'
 /// directives.
 ///
 /// \code
 /// #pragma omp target update from(a,b)
 /// \endcode
 /// In this example directive '#pragma omp target update' has clause 'from'
 /// with the variables 'a' and 'b'.
 class OMPFromClause final
     : public OMPMappableExprListClause<OMPFromClause>,
       private llvm::TrailingObjects<
           OMPFromClause, Expr *, ValueDecl *, unsigned,
           OMPClauseMappableExprCommon::MappableComponent> {
   friend class OMPClauseReader;
   friend OMPMappableExprListClause;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Build clause with number of variables \a NumVars.
   ///
   /// \param MapperQualifierLoc C++ nested name specifier for the associated
   /// user-defined mapper.
   /// \param MapperIdInfo The identifier of associated user-defined mapper.
   /// \param Locs Locations needed to build a mappable clause. It includes 1)
   /// StartLoc: starting location of the clause (the clause keyword); 2)
   /// LParenLoc: location of '('; 3) EndLoc: ending location of the clause.
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   explicit OMPFromClause(NestedNameSpecifierLoc MapperQualifierLoc,
                          DeclarationNameInfo MapperIdInfo,
                          const OMPVarListLocTy &Locs,
                          const OMPMappableExprListSizeTy &Sizes)
       : OMPMappableExprListClause(OMPC_from, Locs, Sizes, &MapperQualifierLoc,
                                   &MapperIdInfo) {}
 
   /// Build an empty clause.
   ///
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   explicit OMPFromClause(const OMPMappableExprListSizeTy &Sizes)
       : OMPMappableExprListClause(OMPC_from, OMPVarListLocTy(), Sizes) {}
 
   /// Define the sizes of each trailing object array except the last one. This
   /// is required for TrailingObjects to work properly.
   size_t numTrailingObjects(OverloadToken<Expr *>) const {
     // There are varlist_size() of expressions, and varlist_size() of
     // user-defined mappers.
     return 2 * varlist_size();
   }
   size_t numTrailingObjects(OverloadToken<ValueDecl *>) const {
     return getUniqueDeclarationsNum();
   }
   size_t numTrailingObjects(OverloadToken<unsigned>) const {
     return getUniqueDeclarationsNum() + getTotalComponentListNum();
   }
 
 public:
   /// Creates clause with a list of variables \a Vars.
   ///
   /// \param C AST context.
   /// \param Locs Locations needed to build a mappable clause. It includes 1)
   /// StartLoc: starting location of the clause (the clause keyword); 2)
   /// LParenLoc: location of '('; 3) EndLoc: ending location of the clause.
   /// \param Vars The original expression used in the clause.
   /// \param Declarations Declarations used in the clause.
   /// \param ComponentLists Component lists used in the clause.
   /// \param UDMapperRefs References to user-defined mappers associated with
   /// expressions used in the clause.
   /// \param UDMQualifierLoc C++ nested name specifier for the associated
   /// user-defined mapper.
   /// \param MapperId The identifier of associated user-defined mapper.
   static OMPFromClause *Create(const ASTContext &C, const OMPVarListLocTy &Locs,
                                ArrayRef<Expr *> Vars,
                                ArrayRef<ValueDecl *> Declarations,
                                MappableExprComponentListsRef ComponentLists,
                                ArrayRef<Expr *> UDMapperRefs,
                                NestedNameSpecifierLoc UDMQualifierLoc,
                                DeclarationNameInfo MapperId);
 
   /// Creates an empty clause with the place for \a NumVars variables.
   ///
   /// \param C AST context.
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   static OMPFromClause *CreateEmpty(const ASTContext &C,
                                     const OMPMappableExprListSizeTy &Sizes);
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPFromClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_from;
   }
 };
 
 /// This represents clause 'use_device_ptr' in the '#pragma omp ...'
 /// directives.
 ///
 /// \code
 /// #pragma omp target data use_device_ptr(a,b)
 /// \endcode
 /// In this example directive '#pragma omp target data' has clause
 /// 'use_device_ptr' with the variables 'a' and 'b'.
 class OMPUseDevicePtrClause final
     : public OMPMappableExprListClause<OMPUseDevicePtrClause>,
       private llvm::TrailingObjects<
           OMPUseDevicePtrClause, Expr *, ValueDecl *, unsigned,
           OMPClauseMappableExprCommon::MappableComponent> {
   friend class OMPClauseReader;
   friend OMPMappableExprListClause;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Build clause with number of variables \a NumVars.
   ///
   /// \param Locs Locations needed to build a mappable clause. It includes 1)
   /// StartLoc: starting location of the clause (the clause keyword); 2)
   /// LParenLoc: location of '('; 3) EndLoc: ending location of the clause.
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   explicit OMPUseDevicePtrClause(const OMPVarListLocTy &Locs,
                                  const OMPMappableExprListSizeTy &Sizes)
       : OMPMappableExprListClause(OMPC_use_device_ptr, Locs, Sizes) {}
 
   /// Build an empty clause.
   ///
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   explicit OMPUseDevicePtrClause(const OMPMappableExprListSizeTy &Sizes)
       : OMPMappableExprListClause(OMPC_use_device_ptr, OMPVarListLocTy(),
                                   Sizes) {}
 
   /// Define the sizes of each trailing object array except the last one. This
   /// is required for TrailingObjects to work properly.
   size_t numTrailingObjects(OverloadToken<Expr *>) const {
     return 3 * varlist_size();
   }
   size_t numTrailingObjects(OverloadToken<ValueDecl *>) const {
     return getUniqueDeclarationsNum();
   }
   size_t numTrailingObjects(OverloadToken<unsigned>) const {
     return getUniqueDeclarationsNum() + getTotalComponentListNum();
   }
 
   /// Sets the list of references to private copies with initializers for new
   /// private variables.
   /// \param VL List of references.
   void setPrivateCopies(ArrayRef<Expr *> VL);
 
   /// Gets the list of references to private copies with initializers for new
   /// private variables.
   MutableArrayRef<Expr *> getPrivateCopies() {
     return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
   }
   ArrayRef<const Expr *> getPrivateCopies() const {
     return llvm::makeArrayRef(varlist_end(), varlist_size());
   }
 
   /// Sets the list of references to initializer variables for new private
   /// variables.
   /// \param VL List of references.
   void setInits(ArrayRef<Expr *> VL);
 
   /// Gets the list of references to initializer variables for new private
   /// variables.
   MutableArrayRef<Expr *> getInits() {
     return MutableArrayRef<Expr *>(getPrivateCopies().end(), varlist_size());
   }
   ArrayRef<const Expr *> getInits() const {
     return llvm::makeArrayRef(getPrivateCopies().end(), varlist_size());
   }
 
 public:
   /// Creates clause with a list of variables \a Vars.
   ///
   /// \param C AST context.
   /// \param Locs Locations needed to build a mappable clause. It includes 1)
   /// StartLoc: starting location of the clause (the clause keyword); 2)
   /// LParenLoc: location of '('; 3) EndLoc: ending location of the clause.
   /// \param Vars The original expression used in the clause.
   /// \param PrivateVars Expressions referring to private copies.
   /// \param Inits Expressions referring to private copy initializers.
   /// \param Declarations Declarations used in the clause.
   /// \param ComponentLists Component lists used in the clause.
   static OMPUseDevicePtrClause *
   Create(const ASTContext &C, const OMPVarListLocTy &Locs,
          ArrayRef<Expr *> Vars, ArrayRef<Expr *> PrivateVars,
          ArrayRef<Expr *> Inits, ArrayRef<ValueDecl *> Declarations,
          MappableExprComponentListsRef ComponentLists);
 
   /// Creates an empty clause with the place for \a NumVars variables.
   ///
   /// \param C AST context.
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   static OMPUseDevicePtrClause *
   CreateEmpty(const ASTContext &C, const OMPMappableExprListSizeTy &Sizes);
 
   using private_copies_iterator = MutableArrayRef<Expr *>::iterator;
   using private_copies_const_iterator = ArrayRef<const Expr *>::iterator;
   using private_copies_range = llvm::iterator_range<private_copies_iterator>;
   using private_copies_const_range =
       llvm::iterator_range<private_copies_const_iterator>;
 
   private_copies_range private_copies() {
     return private_copies_range(getPrivateCopies().begin(),
                                 getPrivateCopies().end());
   }
 
   private_copies_const_range private_copies() const {
     return private_copies_const_range(getPrivateCopies().begin(),
                                       getPrivateCopies().end());
   }
 
   using inits_iterator = MutableArrayRef<Expr *>::iterator;
   using inits_const_iterator = ArrayRef<const Expr *>::iterator;
   using inits_range = llvm::iterator_range<inits_iterator>;
   using inits_const_range = llvm::iterator_range<inits_const_iterator>;
 
   inits_range inits() {
     return inits_range(getInits().begin(), getInits().end());
   }
 
   inits_const_range inits() const {
     return inits_const_range(getInits().begin(), getInits().end());
   }
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPUseDevicePtrClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_use_device_ptr;
   }
 };
 
 /// This represents clause 'is_device_ptr' in the '#pragma omp ...'
 /// directives.
 ///
 /// \code
 /// #pragma omp target is_device_ptr(a,b)
 /// \endcode
 /// In this example directive '#pragma omp target' has clause
 /// 'is_device_ptr' with the variables 'a' and 'b'.
 class OMPIsDevicePtrClause final
     : public OMPMappableExprListClause<OMPIsDevicePtrClause>,
       private llvm::TrailingObjects<
           OMPIsDevicePtrClause, Expr *, ValueDecl *, unsigned,
           OMPClauseMappableExprCommon::MappableComponent> {
   friend class OMPClauseReader;
   friend OMPMappableExprListClause;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Build clause with number of variables \a NumVars.
   ///
   /// \param Locs Locations needed to build a mappable clause. It includes 1)
   /// StartLoc: starting location of the clause (the clause keyword); 2)
   /// LParenLoc: location of '('; 3) EndLoc: ending location of the clause.
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   explicit OMPIsDevicePtrClause(const OMPVarListLocTy &Locs,
                                 const OMPMappableExprListSizeTy &Sizes)
       : OMPMappableExprListClause(OMPC_is_device_ptr, Locs, Sizes) {}
 
   /// Build an empty clause.
   ///
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   explicit OMPIsDevicePtrClause(const OMPMappableExprListSizeTy &Sizes)
       : OMPMappableExprListClause(OMPC_is_device_ptr, OMPVarListLocTy(),
                                   Sizes) {}
 
   /// Define the sizes of each trailing object array except the last one. This
   /// is required for TrailingObjects to work properly.
   size_t numTrailingObjects(OverloadToken<Expr *>) const {
     return varlist_size();
   }
   size_t numTrailingObjects(OverloadToken<ValueDecl *>) const {
     return getUniqueDeclarationsNum();
   }
   size_t numTrailingObjects(OverloadToken<unsigned>) const {
     return getUniqueDeclarationsNum() + getTotalComponentListNum();
   }
 
 public:
   /// Creates clause with a list of variables \a Vars.
   ///
   /// \param C AST context.
   /// \param Locs Locations needed to build a mappable clause. It includes 1)
   /// StartLoc: starting location of the clause (the clause keyword); 2)
   /// LParenLoc: location of '('; 3) EndLoc: ending location of the clause.
   /// \param Vars The original expression used in the clause.
   /// \param Declarations Declarations used in the clause.
   /// \param ComponentLists Component lists used in the clause.
   static OMPIsDevicePtrClause *
   Create(const ASTContext &C, const OMPVarListLocTy &Locs,
          ArrayRef<Expr *> Vars, ArrayRef<ValueDecl *> Declarations,
          MappableExprComponentListsRef ComponentLists);
 
   /// Creates an empty clause with the place for \a NumVars variables.
   ///
   /// \param C AST context.
   /// \param Sizes All required sizes to build a mappable clause. It includes 1)
   /// NumVars: number of expressions listed in this clause; 2)
   /// NumUniqueDeclarations: number of unique base declarations in this clause;
   /// 3) NumComponentLists: number of component lists in this clause; and 4)
   /// NumComponents: total number of expression components in the clause.
   static OMPIsDevicePtrClause *
   CreateEmpty(const ASTContext &C, const OMPMappableExprListSizeTy &Sizes);
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPIsDevicePtrClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_is_device_ptr;
   }
 };
 
 /// This represents clause 'nontemporal' in the '#pragma omp ...' directives.
 ///
 /// \code
 /// #pragma omp simd nontemporal(a)
 /// \endcode
 /// In this example directive '#pragma omp simd' has clause 'nontemporal' for
 /// the variable 'a'.
 class OMPNontemporalClause final
     : public OMPVarListClause<OMPNontemporalClause>,
       private llvm::TrailingObjects<OMPNontemporalClause, Expr *> {
   friend class OMPClauseReader;
   friend OMPVarListClause;
   friend TrailingObjects;
 
   /// Build clause with number of variables \a N.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param N Number of the variables in the clause.
   OMPNontemporalClause(SourceLocation StartLoc, SourceLocation LParenLoc,
                        SourceLocation EndLoc, unsigned N)
       : OMPVarListClause<OMPNontemporalClause>(OMPC_nontemporal, StartLoc,
                                                LParenLoc, EndLoc, N) {}
 
   /// Build an empty clause.
   ///
   /// \param N Number of variables.
   explicit OMPNontemporalClause(unsigned N)
       : OMPVarListClause<OMPNontemporalClause>(
             OMPC_nontemporal, SourceLocation(), SourceLocation(),
             SourceLocation(), N) {}
 
   /// Get the list of privatied copies if the member expression was captured by
   /// one of the privatization clauses.
   MutableArrayRef<Expr *> getPrivateRefs() {
     return MutableArrayRef<Expr *>(varlist_end(), varlist_size());
   }
   ArrayRef<const Expr *> getPrivateRefs() const {
     return llvm::makeArrayRef(varlist_end(), varlist_size());
   }
 
 public:
   /// Creates clause with a list of variables \a VL.
   ///
   /// \param C AST context.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   /// \param VL List of references to the variables.
   static OMPNontemporalClause *
   Create(const ASTContext &C, SourceLocation StartLoc, SourceLocation LParenLoc,
          SourceLocation EndLoc, ArrayRef<Expr *> VL);
 
   /// Creates an empty clause with the place for \a N variables.
   ///
   /// \param C AST context.
   /// \param N The number of variables.
   static OMPNontemporalClause *CreateEmpty(const ASTContext &C, unsigned N);
 
   /// Sets the list of references to private copies created in private clauses.
   /// \param VL List of references.
   void setPrivateRefs(ArrayRef<Expr *> VL);
 
   child_range children() {
     return child_range(reinterpret_cast<Stmt **>(varlist_begin()),
                        reinterpret_cast<Stmt **>(varlist_end()));
   }
 
   const_child_range children() const {
     auto Children = const_cast<OMPNontemporalClause *>(this)->children();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range private_refs() {
     return child_range(reinterpret_cast<Stmt **>(getPrivateRefs().begin()),
                        reinterpret_cast<Stmt **>(getPrivateRefs().end()));
   }
 
   const_child_range private_refs() const {
     auto Children = const_cast<OMPNontemporalClause *>(this)->private_refs();
     return const_child_range(Children.begin(), Children.end());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_nontemporal;
   }
 };
 
 /// This represents 'order' clause in the '#pragma omp ...' directive.
 ///
 /// \code
 /// #pragma omp simd order(concurrent)
 /// \endcode
 /// In this example directive '#pragma omp parallel' has simple 'order'
 /// clause with kind 'concurrent'.
 class OMPOrderClause final : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// A kind of the 'default' clause.
   OpenMPOrderClauseKind Kind = OMPC_ORDER_unknown;
 
   /// Start location of the kind in source code.
   SourceLocation KindKwLoc;
 
   /// Set kind of the clause.
   ///
   /// \param K Argument of clause.
   void setKind(OpenMPOrderClauseKind K) { Kind = K; }
 
   /// Set argument location.
   ///
   /// \param KLoc Argument location.
   void setKindKwLoc(SourceLocation KLoc) { KindKwLoc = KLoc; }
 
 public:
   /// Build 'order' clause with argument \p A ('concurrent').
   ///
   /// \param A Argument of the clause ('concurrent').
   /// \param ALoc Starting location of the argument.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPOrderClause(OpenMPOrderClauseKind A, SourceLocation ALoc,
                  SourceLocation StartLoc, SourceLocation LParenLoc,
                  SourceLocation EndLoc)
       : OMPClause(OMPC_order, StartLoc, EndLoc), LParenLoc(LParenLoc), Kind(A),
         KindKwLoc(ALoc) {}
 
   /// Build an empty clause.
   OMPOrderClause()
       : OMPClause(OMPC_order, SourceLocation(), SourceLocation()) {}
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Returns kind of the clause.
   OpenMPOrderClauseKind getKind() const { return Kind; }
 
   /// Returns location of clause kind.
   SourceLocation getKindKwLoc() const { return KindKwLoc; }
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_order;
   }
 };
 
 /// This represents 'destroy' clause in the '#pragma omp depobj'
 /// directive.
 ///
 /// \code
 /// #pragma omp depobj(a) destroy
 /// \endcode
 /// In this example directive '#pragma omp depobj' has 'destroy' clause.
 class OMPDestroyClause final : public OMPClause {
 public:
   /// Build 'destroy' clause.
   ///
   /// \param StartLoc Starting location of the clause.
   /// \param EndLoc Ending location of the clause.
   OMPDestroyClause(SourceLocation StartLoc, SourceLocation EndLoc)
       : OMPClause(OMPC_destroy, StartLoc, EndLoc) {}
 
   /// Build an empty clause.
   OMPDestroyClause()
       : OMPClause(OMPC_destroy, SourceLocation(), SourceLocation()) {}
 
   child_range children() {
     return child_range(child_iterator(), child_iterator());
   }
 
   const_child_range children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_destroy;
   }
 };
 
 /// This represents 'detach' clause in the '#pragma omp task' directive.
 ///
 /// \code
 /// #pragma omp task detach(evt)
 /// \endcode
 /// In this example directive '#pragma omp detach' has simple 'detach' clause
 /// with the variable 'evt'.
 class OMPDetachClause final : public OMPClause {
   friend class OMPClauseReader;
 
   /// Location of '('.
   SourceLocation LParenLoc;
 
   /// Expression of the 'detach' clause.
   Stmt *Evt = nullptr;
 
   /// Set condition.
   void setEventHandler(Expr *E) { Evt = E; }
 
   /// Sets the location of '('.
   void setLParenLoc(SourceLocation Loc) { LParenLoc = Loc; }
 
 public:
   /// Build 'detach' clause with event-handler \a Evt.
   ///
   /// \param Evt Event handler expression.
   /// \param StartLoc Starting location of the clause.
   /// \param LParenLoc Location of '('.
   /// \param EndLoc Ending location of the clause.
   OMPDetachClause(Expr *Evt, SourceLocation StartLoc, SourceLocation LParenLoc,
                   SourceLocation EndLoc)
       : OMPClause(OMPC_detach, StartLoc, EndLoc), LParenLoc(LParenLoc),
         Evt(Evt) {}
 
   /// Build an empty clause.
   OMPDetachClause()
       : OMPClause(OMPC_detach, SourceLocation(), SourceLocation()) {}
 
   /// Returns the location of '('.
   SourceLocation getLParenLoc() const { return LParenLoc; }
 
   /// Returns event-handler expression.
   Expr *getEventHandler() const { return cast_or_null<Expr>(Evt); }
 
   child_range children() { return child_range(&Evt, &Evt + 1); }
 
   const_child_range children() const {
     return const_child_range(&Evt, &Evt + 1);
   }
 
   child_range used_children() {
     return child_range(child_iterator(), child_iterator());
   }
   const_child_range used_children() const {
     return const_child_range(const_child_iterator(), const_child_iterator());
   }
 
   static bool classof(const OMPClause *T) {
     return T->getClauseKind() == OMPC_detach;
   }
 };
 
 /// This class implements a simple visitor for OMPClause
 /// subclasses.
 template<class ImplClass, template <typename> class Ptr, typename RetTy>
 class OMPClauseVisitorBase {
 public:
 #define PTR(CLASS) Ptr<CLASS>
 #define DISPATCH(CLASS) \
   return static_cast<ImplClass*>(this)->Visit##CLASS(static_cast<PTR(CLASS)>(S))
 
 #define OPENMP_CLAUSE(Name, Class)                              \
   RetTy Visit ## Class (PTR(Class) S) { DISPATCH(Class); }
 #include "clang/Basic/OpenMPKinds.def"
 
   RetTy Visit(PTR(OMPClause) S) {
     // Top switch clause: visit each OMPClause.
     switch (S->getClauseKind()) {
     default: llvm_unreachable("Unknown clause kind!");
 #define OPENMP_CLAUSE(Name, Class)                              \
     case OMPC_ ## Name : return Visit ## Class(static_cast<PTR(Class)>(S));
 #include "clang/Basic/OpenMPKinds.def"
     }
   }
   // Base case, ignore it. :)
   RetTy VisitOMPClause(PTR(OMPClause) Node) { return RetTy(); }
 #undef PTR
 #undef DISPATCH
 };
 
 template <typename T> using const_ptr = std::add_pointer_t<std::add_const_t<T>>;
 
 template <class ImplClass, typename RetTy = void>
 class OMPClauseVisitor
     : public OMPClauseVisitorBase<ImplClass, std::add_pointer_t, RetTy> {};
 template<class ImplClass, typename RetTy = void>
 class ConstOMPClauseVisitor :
       public OMPClauseVisitorBase <ImplClass, const_ptr, RetTy> {};
 
 class OMPClausePrinter final : public OMPClauseVisitor<OMPClausePrinter> {
   raw_ostream &OS;
   const PrintingPolicy &Policy;
 
   /// Process clauses with list of variables.
   template <typename T> void VisitOMPClauseList(T *Node, char StartSym);
 
 public:
   OMPClausePrinter(raw_ostream &OS, const PrintingPolicy &Policy)
       : OS(OS), Policy(Policy) {}
 
 #define OPENMP_CLAUSE(Name, Class) void Visit##Class(Class *S);
 #include "clang/Basic/OpenMPKinds.def"
 };
 
 /// Helper data structure representing the traits in a match clause of an
 /// `declare variant` or `metadirective`. The outer level is an ordered
 /// collection of selector sets, each with an associated kind and an ordered
 /// collection of selectors. A selector has a kind, an optional score/condition,
 /// and an ordered collection of properties.
 struct OMPTraitInfo {
   struct OMPTraitProperty {
     llvm::omp::TraitProperty Kind = llvm::omp::TraitProperty::invalid;
   };
   struct OMPTraitSelector {
     Expr *ScoreOrCondition = nullptr;
     llvm::omp::TraitSelector Kind = llvm::omp::TraitSelector::invalid;
     llvm::SmallVector<OMPTraitProperty, 4> Properties;
   };
   struct OMPTraitSet {
     llvm::omp::TraitSet Kind = llvm::omp::TraitSet::invalid;
     llvm::SmallVector<OMPTraitSelector, 4> Selectors;
   };
 
   /// The outermost level of selector sets.
   llvm::SmallVector<OMPTraitSet, 4> Sets;
 
   bool anyScoreOrCondition(
       const llvm::function_ref<bool(Expr *&, bool /* IsScore */)> &Cond) {
     return llvm::any_of(Sets, [&Cond](OMPTraitInfo::OMPTraitSet &Set) {
       return llvm::any_of(
           Set.Selectors, [&Cond](OMPTraitInfo::OMPTraitSelector &Selector) {
             return Cond(Selector.ScoreOrCondition,
                         /* IsScore */ Selector.Kind !=
                             llvm::omp::TraitSelector::user_condition);
           });
     });
   }
 
   /// Create a variant match info object from this trait info object. While the
   /// former is a flat representation the actual main difference is that the
   /// latter uses clang::Expr to store the score/condition while the former is
   /// independent of clang. Thus, expressions and conditions are evaluated in
   /// this method.
   void getAsVariantMatchInfo(ASTContext &ASTCtx,
                              llvm::omp::VariantMatchInfo &VMI) const;
 
   /// Print a human readable representation into \p OS.
   void print(llvm::raw_ostream &OS, const PrintingPolicy &Policy) const;
 };
 llvm::raw_ostream &operator<<(llvm::raw_ostream &OS, const OMPTraitInfo &TI);
 
 } // namespace clang
 
 #endif // LLVM_CLANG_AST_OPENMPCLAUSE_H
diff --git a/clang/include/clang/Basic/OpenMPKinds.def b/clang/include/clang/Basic/OpenMPKinds.def
index e6a4aa1d1f58..0488dad6706b 100644
--- a/clang/include/clang/Basic/OpenMPKinds.def
+++ b/clang/include/clang/Basic/OpenMPKinds.def
@@ -1,1160 +1,1168 @@
 //===--- OpenMPKinds.def - OpenMP directives and clauses list ---*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 /// \file
 /// This file defines the list of supported OpenMP directives and
 /// clauses.
 ///
 //===----------------------------------------------------------------------===//
 
 #ifndef OPENMP_CLAUSE
 #  define OPENMP_CLAUSE(Name, Class)
 #endif
 #ifndef OPENMP_PARALLEL_CLAUSE
 #  define OPENMP_PARALLEL_CLAUSE(Name)
 #endif
 #ifndef OPENMP_SIMD_CLAUSE
 #  define OPENMP_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_FOR_CLAUSE
 #  define OPENMP_FOR_CLAUSE(Name)
 #endif
 #ifndef OPENMP_FOR_SIMD_CLAUSE
 #  define OPENMP_FOR_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_SECTIONS_CLAUSE
 #  define OPENMP_SECTIONS_CLAUSE(Name)
 #endif
 #ifndef OPENMP_SINGLE_CLAUSE
 #  define OPENMP_SINGLE_CLAUSE(Name)
 #endif
 #ifndef OPENMP_PARALLEL_FOR_CLAUSE
 #  define OPENMP_PARALLEL_FOR_CLAUSE(Name)
 #endif
 #ifndef OPENMP_PARALLEL_FOR_SIMD_CLAUSE
 #  define OPENMP_PARALLEL_FOR_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_PARALLEL_MASTER_CLAUSE
 #  define OPENMP_PARALLEL_MASTER_CLAUSE(Name)
 #endif
 #ifndef OPENMP_PARALLEL_SECTIONS_CLAUSE
 #  define OPENMP_PARALLEL_SECTIONS_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TASK_CLAUSE
 #  define OPENMP_TASK_CLAUSE(Name)
 #endif
 #ifndef OPENMP_ATOMIC_CLAUSE
 #  define OPENMP_ATOMIC_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_CLAUSE
 #  define OPENMP_TARGET_CLAUSE(Name)
 #endif
 #ifndef OPENMP_REQUIRES_CLAUSE
 # define OPENMP_REQUIRES_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_DATA_CLAUSE
 #  define OPENMP_TARGET_DATA_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_ENTER_DATA_CLAUSE
 #define OPENMP_TARGET_ENTER_DATA_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_EXIT_DATA_CLAUSE
 #define OPENMP_TARGET_EXIT_DATA_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_PARALLEL_CLAUSE
 #  define OPENMP_TARGET_PARALLEL_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_PARALLEL_FOR_CLAUSE
 #  define OPENMP_TARGET_PARALLEL_FOR_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_UPDATE_CLAUSE
 #  define OPENMP_TARGET_UPDATE_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TEAMS_CLAUSE
 #  define OPENMP_TEAMS_CLAUSE(Name)
 #endif
 #ifndef OPENMP_CANCEL_CLAUSE
 #  define OPENMP_CANCEL_CLAUSE(Name)
 #endif
 #ifndef OPENMP_ORDERED_CLAUSE
 #  define OPENMP_ORDERED_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TASKLOOP_CLAUSE
 #  define OPENMP_TASKLOOP_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TASKLOOP_SIMD_CLAUSE
 #  define OPENMP_TASKLOOP_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_MASTER_TASKLOOP_CLAUSE
 #  define OPENMP_MASTER_TASKLOOP_CLAUSE(Name)
 #endif
 #ifndef OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE
 #  define OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE
 #  define OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(Name)
 #endif
 #ifndef OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE
 #  define OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_CRITICAL_CLAUSE
 #  define OPENMP_CRITICAL_CLAUSE(Name)
 #endif
 #ifndef OPENMP_DISTRIBUTE_CLAUSE
 #define OPENMP_DISTRIBUTE_CLAUSE(Name)
 #endif
 #ifndef OPENMP_SCHEDULE_KIND
 #define OPENMP_SCHEDULE_KIND(Name)
 #endif
 #ifndef OPENMP_SCHEDULE_MODIFIER
 #define OPENMP_SCHEDULE_MODIFIER(Name)
 #endif
 #ifndef OPENMP_DEPEND_KIND
 #define OPENMP_DEPEND_KIND(Name)
 #endif
 #ifndef OPENMP_LINEAR_KIND
 #define OPENMP_LINEAR_KIND(Name)
 #endif
 #ifndef OPENMP_MAP_KIND
 #define OPENMP_MAP_KIND(Name)
 #endif
 #ifndef OPENMP_MAP_MODIFIER_KIND
 #define OPENMP_MAP_MODIFIER_KIND(Name)
 #endif
 #ifndef OPENMP_TO_MODIFIER_KIND
 #define OPENMP_TO_MODIFIER_KIND(Name)
 #endif
 #ifndef OPENMP_FROM_MODIFIER_KIND
 #define OPENMP_FROM_MODIFIER_KIND(Name)
 #endif
 #ifndef OPENMP_DIST_SCHEDULE_KIND
 #define OPENMP_DIST_SCHEDULE_KIND(Name)
 #endif
 #ifndef OPENMP_DEFAULTMAP_KIND
 #define OPENMP_DEFAULTMAP_KIND(Name)
 #endif
 #ifndef OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND
 #define OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND(Name)
 #endif
 #ifndef OPENMP_DEFAULTMAP_MODIFIER
 #define OPENMP_DEFAULTMAP_MODIFIER(Name)
 #endif
 #ifndef OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE
 #define OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(Name)
 #endif
 #ifndef OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE
 #define OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_DISTRIBUTE_SIMD_CLAUSE
 #define OPENMP_DISTRIBUTE_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE
 #define OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_SIMD_CLAUSE
 #define OPENMP_TARGET_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TEAMS_DISTRIBUTE_CLAUSE
 #define OPENMP_TEAMS_DISTRIBUTE_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE
 #define OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE
 #define OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE
 #define OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_TEAMS_CLAUSE
 #define OPENMP_TARGET_TEAMS_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE
 #define OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE
 #define OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE
 #define OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE
 #define OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(Name)
 #endif
 #ifndef OPENMP_TASKGROUP_CLAUSE
 #define OPENMP_TASKGROUP_CLAUSE(Name)
 #endif
 #ifndef OPENMP_DECLARE_MAPPER_CLAUSE
 #define OPENMP_DECLARE_MAPPER_CLAUSE(Name)
 #endif
 #ifndef OPENMP_ALLOCATE_CLAUSE
 # define OPENMP_ALLOCATE_CLAUSE(Name)
 #endif
 #ifndef OPENMP_DEVICE_TYPE_KIND
 #define OPENMP_DEVICE_TYPE_KIND(Name)
 #endif
 #ifndef OPENMP_DECLARE_VARIANT_CLAUSE
 #define OPENMP_DECLARE_VARIANT_CLAUSE(Name)
 #endif
 #ifndef OPENMP_LASTPRIVATE_KIND
 #define OPENMP_LASTPRIVATE_KIND(Name)
 #endif
 #ifndef OPENMP_ORDER_KIND
 #define OPENMP_ORDER_KIND(Name)
 #endif
 #ifndef OPENMP_FLUSH_CLAUSE
 #define OPENMP_FLUSH_CLAUSE(Name)
 #endif
 #ifndef OPENMP_DEPOBJ_CLAUSE
 #define OPENMP_DEPOBJ_CLAUSE(Name)
 #endif
+#ifndef OPENMP_DEVICE_MODIFIER
+#define OPENMP_DEVICE_MODIFIER(Name)
+#endif
 
 // OpenMP clauses.
 OPENMP_CLAUSE(allocator, OMPAllocatorClause)
 OPENMP_CLAUSE(if, OMPIfClause)
 OPENMP_CLAUSE(final, OMPFinalClause)
 OPENMP_CLAUSE(num_threads, OMPNumThreadsClause)
 OPENMP_CLAUSE(safelen, OMPSafelenClause)
 OPENMP_CLAUSE(simdlen, OMPSimdlenClause)
 OPENMP_CLAUSE(collapse, OMPCollapseClause)
 OPENMP_CLAUSE(default, OMPDefaultClause)
 OPENMP_CLAUSE(private, OMPPrivateClause)
 OPENMP_CLAUSE(firstprivate, OMPFirstprivateClause)
 OPENMP_CLAUSE(lastprivate, OMPLastprivateClause)
 OPENMP_CLAUSE(shared,  OMPSharedClause)
 OPENMP_CLAUSE(reduction,  OMPReductionClause)
 OPENMP_CLAUSE(linear,  OMPLinearClause)
 OPENMP_CLAUSE(aligned, OMPAlignedClause)
 OPENMP_CLAUSE(copyin,  OMPCopyinClause)
 OPENMP_CLAUSE(copyprivate,  OMPCopyprivateClause)
 OPENMP_CLAUSE(proc_bind, OMPProcBindClause)
 OPENMP_CLAUSE(schedule, OMPScheduleClause)
 OPENMP_CLAUSE(ordered, OMPOrderedClause)
 OPENMP_CLAUSE(nowait, OMPNowaitClause)
 OPENMP_CLAUSE(untied, OMPUntiedClause)
 OPENMP_CLAUSE(mergeable, OMPMergeableClause)
 OPENMP_CLAUSE(flush, OMPFlushClause)
 OPENMP_CLAUSE(read, OMPReadClause)
 OPENMP_CLAUSE(write, OMPWriteClause)
 OPENMP_CLAUSE(update, OMPUpdateClause)
 OPENMP_CLAUSE(capture, OMPCaptureClause)
 OPENMP_CLAUSE(seq_cst, OMPSeqCstClause)
 OPENMP_CLAUSE(acq_rel, OMPAcqRelClause)
 OPENMP_CLAUSE(acquire, OMPAcquireClause)
 OPENMP_CLAUSE(release, OMPReleaseClause)
 OPENMP_CLAUSE(relaxed, OMPRelaxedClause)
 OPENMP_CLAUSE(depend, OMPDependClause)
 OPENMP_CLAUSE(device, OMPDeviceClause)
 OPENMP_CLAUSE(threads, OMPThreadsClause)
 OPENMP_CLAUSE(simd, OMPSIMDClause)
 OPENMP_CLAUSE(map, OMPMapClause)
 OPENMP_CLAUSE(num_teams, OMPNumTeamsClause)
 OPENMP_CLAUSE(thread_limit, OMPThreadLimitClause)
 OPENMP_CLAUSE(priority, OMPPriorityClause)
 OPENMP_CLAUSE(grainsize, OMPGrainsizeClause)
 OPENMP_CLAUSE(nogroup, OMPNogroupClause)
 OPENMP_CLAUSE(num_tasks, OMPNumTasksClause)
 OPENMP_CLAUSE(hint, OMPHintClause)
 OPENMP_CLAUSE(dist_schedule, OMPDistScheduleClause)
 OPENMP_CLAUSE(defaultmap, OMPDefaultmapClause)
 OPENMP_CLAUSE(to, OMPToClause)
 OPENMP_CLAUSE(from, OMPFromClause)
 OPENMP_CLAUSE(use_device_ptr, OMPUseDevicePtrClause)
 OPENMP_CLAUSE(is_device_ptr, OMPIsDevicePtrClause)
 OPENMP_CLAUSE(task_reduction,  OMPTaskReductionClause)
 OPENMP_CLAUSE(in_reduction,  OMPInReductionClause)
 OPENMP_CLAUSE(unified_address, OMPUnifiedAddressClause)
 OPENMP_CLAUSE(unified_shared_memory, OMPUnifiedSharedMemoryClause)
 OPENMP_CLAUSE(reverse_offload, OMPReverseOffloadClause)
 OPENMP_CLAUSE(dynamic_allocators, OMPDynamicAllocatorsClause)
 OPENMP_CLAUSE(atomic_default_mem_order, OMPAtomicDefaultMemOrderClause)
 OPENMP_CLAUSE(allocate, OMPAllocateClause)
 OPENMP_CLAUSE(nontemporal, OMPNontemporalClause)
 OPENMP_CLAUSE(order, OMPOrderClause)
 OPENMP_CLAUSE(depobj, OMPDepobjClause)
 OPENMP_CLAUSE(destroy, OMPDestroyClause)
 OPENMP_CLAUSE(detach, OMPDetachClause)
 
 // Clauses allowed for OpenMP directive 'parallel'.
 OPENMP_PARALLEL_CLAUSE(if)
 OPENMP_PARALLEL_CLAUSE(num_threads)
 OPENMP_PARALLEL_CLAUSE(default)
 OPENMP_PARALLEL_CLAUSE(proc_bind)
 OPENMP_PARALLEL_CLAUSE(private)
 OPENMP_PARALLEL_CLAUSE(firstprivate)
 OPENMP_PARALLEL_CLAUSE(shared)
 OPENMP_PARALLEL_CLAUSE(reduction)
 OPENMP_PARALLEL_CLAUSE(copyin)
 OPENMP_PARALLEL_CLAUSE(allocate)
 
 // Clauses allowed for directive 'omp simd'.
 OPENMP_SIMD_CLAUSE(private)
 OPENMP_SIMD_CLAUSE(lastprivate)
 OPENMP_SIMD_CLAUSE(linear)
 OPENMP_SIMD_CLAUSE(aligned)
 OPENMP_SIMD_CLAUSE(safelen)
 OPENMP_SIMD_CLAUSE(simdlen)
 OPENMP_SIMD_CLAUSE(collapse)
 OPENMP_SIMD_CLAUSE(reduction)
 OPENMP_SIMD_CLAUSE(allocate)
 OPENMP_SIMD_CLAUSE(if)
 OPENMP_SIMD_CLAUSE(nontemporal)
 OPENMP_SIMD_CLAUSE(order)
 
 // Clauses allowed for directive 'omp for'.
 OPENMP_FOR_CLAUSE(private)
 OPENMP_FOR_CLAUSE(lastprivate)
 OPENMP_FOR_CLAUSE(firstprivate)
 OPENMP_FOR_CLAUSE(reduction)
 OPENMP_FOR_CLAUSE(collapse)
 OPENMP_FOR_CLAUSE(schedule)
 OPENMP_FOR_CLAUSE(ordered)
 OPENMP_FOR_CLAUSE(nowait)
 OPENMP_FOR_CLAUSE(linear)
 OPENMP_FOR_CLAUSE(allocate)
 OPENMP_FOR_CLAUSE(order)
 
 // Clauses allowed for directive 'omp for simd'.
 OPENMP_FOR_SIMD_CLAUSE(private)
 OPENMP_FOR_SIMD_CLAUSE(firstprivate)
 OPENMP_FOR_SIMD_CLAUSE(lastprivate)
 OPENMP_FOR_SIMD_CLAUSE(reduction)
 OPENMP_FOR_SIMD_CLAUSE(schedule)
 OPENMP_FOR_SIMD_CLAUSE(collapse)
 OPENMP_FOR_SIMD_CLAUSE(nowait)
 OPENMP_FOR_SIMD_CLAUSE(safelen)
 OPENMP_FOR_SIMD_CLAUSE(simdlen)
 OPENMP_FOR_SIMD_CLAUSE(linear)
 OPENMP_FOR_SIMD_CLAUSE(aligned)
 OPENMP_FOR_SIMD_CLAUSE(ordered)
 OPENMP_FOR_SIMD_CLAUSE(allocate)
 OPENMP_FOR_SIMD_CLAUSE(if)
 OPENMP_FOR_SIMD_CLAUSE(nontemporal)
 OPENMP_FOR_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'omp sections'.
 OPENMP_SECTIONS_CLAUSE(private)
 OPENMP_SECTIONS_CLAUSE(lastprivate)
 OPENMP_SECTIONS_CLAUSE(firstprivate)
 OPENMP_SECTIONS_CLAUSE(reduction)
 OPENMP_SECTIONS_CLAUSE(nowait)
 OPENMP_SECTIONS_CLAUSE(allocate)
 
 // Clauses allowed for directive 'omp single'.
 OPENMP_SINGLE_CLAUSE(private)
 OPENMP_SINGLE_CLAUSE(firstprivate)
 OPENMP_SINGLE_CLAUSE(copyprivate)
 OPENMP_SINGLE_CLAUSE(nowait)
 OPENMP_SINGLE_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'cancel'.
 OPENMP_CANCEL_CLAUSE(if)
 
 // Static attributes for 'schedule' clause.
 OPENMP_SCHEDULE_KIND(static)
 OPENMP_SCHEDULE_KIND(dynamic)
 OPENMP_SCHEDULE_KIND(guided)
 OPENMP_SCHEDULE_KIND(auto)
 OPENMP_SCHEDULE_KIND(runtime)
 
 // Modifiers for 'schedule' clause.
 OPENMP_SCHEDULE_MODIFIER(monotonic)
 OPENMP_SCHEDULE_MODIFIER(nonmonotonic)
 OPENMP_SCHEDULE_MODIFIER(simd)
 
+// Modifiers for 'device' clause.
+OPENMP_DEVICE_MODIFIER(ancestor)
+OPENMP_DEVICE_MODIFIER(device_num)
+
 // Static attributes for 'defaultmap' clause.
 OPENMP_DEFAULTMAP_KIND(scalar)
 OPENMP_DEFAULTMAP_KIND(aggregate)
 OPENMP_DEFAULTMAP_KIND(pointer)
 
 // Modifiers for 'defaultmap' clause.
 OPENMP_DEFAULTMAP_MODIFIER(alloc)
 OPENMP_DEFAULTMAP_MODIFIER(to)
 OPENMP_DEFAULTMAP_MODIFIER(from)
 OPENMP_DEFAULTMAP_MODIFIER(tofrom)
 OPENMP_DEFAULTMAP_MODIFIER(firstprivate)
 OPENMP_DEFAULTMAP_MODIFIER(none)
 OPENMP_DEFAULTMAP_MODIFIER(default)
 
 // Static attributes for 'depend' clause.
 OPENMP_DEPEND_KIND(in)
 OPENMP_DEPEND_KIND(out)
 OPENMP_DEPEND_KIND(inout)
 OPENMP_DEPEND_KIND(mutexinoutset)
 OPENMP_DEPEND_KIND(depobj)
 OPENMP_DEPEND_KIND(source)
 OPENMP_DEPEND_KIND(sink)
 
 // Modifiers for 'linear' clause.
 OPENMP_LINEAR_KIND(val)
 OPENMP_LINEAR_KIND(ref)
 OPENMP_LINEAR_KIND(uval)
 
 // Clauses allowed for OpenMP directive 'parallel for'.
 OPENMP_PARALLEL_FOR_CLAUSE(if)
 OPENMP_PARALLEL_FOR_CLAUSE(num_threads)
 OPENMP_PARALLEL_FOR_CLAUSE(default)
 OPENMP_PARALLEL_FOR_CLAUSE(proc_bind)
 OPENMP_PARALLEL_FOR_CLAUSE(private)
 OPENMP_PARALLEL_FOR_CLAUSE(firstprivate)
 OPENMP_PARALLEL_FOR_CLAUSE(shared)
 OPENMP_PARALLEL_FOR_CLAUSE(reduction)
 OPENMP_PARALLEL_FOR_CLAUSE(copyin)
 OPENMP_PARALLEL_FOR_CLAUSE(lastprivate)
 OPENMP_PARALLEL_FOR_CLAUSE(collapse)
 OPENMP_PARALLEL_FOR_CLAUSE(schedule)
 OPENMP_PARALLEL_FOR_CLAUSE(ordered)
 OPENMP_PARALLEL_FOR_CLAUSE(linear)
 OPENMP_PARALLEL_FOR_CLAUSE(allocate)
 OPENMP_PARALLEL_FOR_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'parallel for simd'.
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(if)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(num_threads)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(default)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(proc_bind)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(private)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(firstprivate)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(shared)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(reduction)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(copyin)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(lastprivate)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(collapse)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(schedule)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(safelen)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(simdlen)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(linear)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(aligned)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(ordered)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(allocate)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(nontemporal)
 OPENMP_PARALLEL_FOR_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'parallel master'.
 OPENMP_PARALLEL_MASTER_CLAUSE(if)
 OPENMP_PARALLEL_MASTER_CLAUSE(num_threads)
 OPENMP_PARALLEL_MASTER_CLAUSE(default)
 OPENMP_PARALLEL_MASTER_CLAUSE(private)
 OPENMP_PARALLEL_MASTER_CLAUSE(firstprivate)
 OPENMP_PARALLEL_MASTER_CLAUSE(shared)
 OPENMP_PARALLEL_MASTER_CLAUSE(copyin)
 OPENMP_PARALLEL_MASTER_CLAUSE(reduction)
 OPENMP_PARALLEL_MASTER_CLAUSE(proc_bind)
 OPENMP_PARALLEL_MASTER_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'parallel sections'.
 OPENMP_PARALLEL_SECTIONS_CLAUSE(if)
 OPENMP_PARALLEL_SECTIONS_CLAUSE(num_threads)
 OPENMP_PARALLEL_SECTIONS_CLAUSE(default)
 OPENMP_PARALLEL_SECTIONS_CLAUSE(proc_bind)
 OPENMP_PARALLEL_SECTIONS_CLAUSE(private)
 OPENMP_PARALLEL_SECTIONS_CLAUSE(firstprivate)
 OPENMP_PARALLEL_SECTIONS_CLAUSE(shared)
 OPENMP_PARALLEL_SECTIONS_CLAUSE(reduction)
 OPENMP_PARALLEL_SECTIONS_CLAUSE(copyin)
 OPENMP_PARALLEL_SECTIONS_CLAUSE(lastprivate)
 OPENMP_PARALLEL_SECTIONS_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'task'.
 OPENMP_TASK_CLAUSE(if)
 OPENMP_TASK_CLAUSE(final)
 OPENMP_TASK_CLAUSE(default)
 OPENMP_TASK_CLAUSE(private)
 OPENMP_TASK_CLAUSE(firstprivate)
 OPENMP_TASK_CLAUSE(shared)
 OPENMP_TASK_CLAUSE(untied)
 OPENMP_TASK_CLAUSE(mergeable)
 OPENMP_TASK_CLAUSE(depend)
 OPENMP_TASK_CLAUSE(priority)
 OPENMP_TASK_CLAUSE(in_reduction)
 OPENMP_TASK_CLAUSE(allocate)
 OPENMP_TASK_CLAUSE(detach)
 
 // Clauses allowed for OpenMP directive 'atomic'.
 OPENMP_ATOMIC_CLAUSE(read)
 OPENMP_ATOMIC_CLAUSE(write)
 OPENMP_ATOMIC_CLAUSE(update)
 OPENMP_ATOMIC_CLAUSE(capture)
 OPENMP_ATOMIC_CLAUSE(seq_cst)
 OPENMP_ATOMIC_CLAUSE(acq_rel)
 OPENMP_ATOMIC_CLAUSE(acquire)
 OPENMP_ATOMIC_CLAUSE(release)
 OPENMP_ATOMIC_CLAUSE(relaxed)
 OPENMP_ATOMIC_CLAUSE(hint)
 
 // Clauses allowed for OpenMP directive 'target'.
 OPENMP_TARGET_CLAUSE(if)
 OPENMP_TARGET_CLAUSE(device)
 OPENMP_TARGET_CLAUSE(map)
 OPENMP_TARGET_CLAUSE(private)
 OPENMP_TARGET_CLAUSE(nowait)
 OPENMP_TARGET_CLAUSE(depend)
 OPENMP_TARGET_CLAUSE(defaultmap)
 OPENMP_TARGET_CLAUSE(firstprivate)
 OPENMP_TARGET_CLAUSE(is_device_ptr)
 OPENMP_TARGET_CLAUSE(reduction)
 OPENMP_TARGET_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'requires'.
 OPENMP_REQUIRES_CLAUSE(unified_address)
 OPENMP_REQUIRES_CLAUSE(unified_shared_memory)
 OPENMP_REQUIRES_CLAUSE(reverse_offload)
 OPENMP_REQUIRES_CLAUSE(dynamic_allocators)
 OPENMP_REQUIRES_CLAUSE(atomic_default_mem_order)
 
 // Clauses allowed for OpenMP directive 'allocate'.
 OPENMP_ALLOCATE_CLAUSE(allocator)
 
 // Modifiers for 'atomic_default_mem_order' clause.
 OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND(seq_cst)
 OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND(acq_rel)
 OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND(relaxed)
 
 // Clauses allowed for OpenMP directive 'target data'.
 OPENMP_TARGET_DATA_CLAUSE(if)
 OPENMP_TARGET_DATA_CLAUSE(device)
 OPENMP_TARGET_DATA_CLAUSE(map)
 OPENMP_TARGET_DATA_CLAUSE(use_device_ptr)
 
 // Clauses allowed for OpenMP directive 'target enter data'.
 OPENMP_TARGET_ENTER_DATA_CLAUSE(if)
 OPENMP_TARGET_ENTER_DATA_CLAUSE(device)
 OPENMP_TARGET_ENTER_DATA_CLAUSE(map)
 OPENMP_TARGET_ENTER_DATA_CLAUSE(nowait)
 OPENMP_TARGET_ENTER_DATA_CLAUSE(depend)
 
 // Clauses allowed for OpenMP directive 'target exit data'.
 OPENMP_TARGET_EXIT_DATA_CLAUSE(if)
 OPENMP_TARGET_EXIT_DATA_CLAUSE(device)
 OPENMP_TARGET_EXIT_DATA_CLAUSE(map)
 OPENMP_TARGET_EXIT_DATA_CLAUSE(nowait)
 OPENMP_TARGET_EXIT_DATA_CLAUSE(depend)
 
 // Clauses allowed for OpenMP directive 'target parallel'.
 OPENMP_TARGET_PARALLEL_CLAUSE(if)
 OPENMP_TARGET_PARALLEL_CLAUSE(device)
 OPENMP_TARGET_PARALLEL_CLAUSE(map)
 OPENMP_TARGET_PARALLEL_CLAUSE(private)
 OPENMP_TARGET_PARALLEL_CLAUSE(firstprivate)
 OPENMP_TARGET_PARALLEL_CLAUSE(nowait)
 OPENMP_TARGET_PARALLEL_CLAUSE(depend)
 OPENMP_TARGET_PARALLEL_CLAUSE(defaultmap)
 OPENMP_TARGET_PARALLEL_CLAUSE(num_threads)
 OPENMP_TARGET_PARALLEL_CLAUSE(default)
 OPENMP_TARGET_PARALLEL_CLAUSE(proc_bind)
 OPENMP_TARGET_PARALLEL_CLAUSE(shared)
 OPENMP_TARGET_PARALLEL_CLAUSE(reduction)
 OPENMP_TARGET_PARALLEL_CLAUSE(is_device_ptr)
 OPENMP_TARGET_PARALLEL_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'target parallel for'.
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(if)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(device)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(map)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(private)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(firstprivate)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(lastprivate)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(nowait)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(depend)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(defaultmap)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(num_threads)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(default)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(proc_bind)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(shared)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(reduction)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(collapse)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(schedule)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(ordered)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(linear)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(is_device_ptr)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(allocate)
 OPENMP_TARGET_PARALLEL_FOR_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'target update'.
 OPENMP_TARGET_UPDATE_CLAUSE(if)
 OPENMP_TARGET_UPDATE_CLAUSE(device)
 OPENMP_TARGET_UPDATE_CLAUSE(to)
 OPENMP_TARGET_UPDATE_CLAUSE(from)
 OPENMP_TARGET_UPDATE_CLAUSE(nowait)
 OPENMP_TARGET_UPDATE_CLAUSE(depend)
 
 // Clauses allowed for OpenMP directive 'teams'.
 OPENMP_TEAMS_CLAUSE(default)
 OPENMP_TEAMS_CLAUSE(private)
 OPENMP_TEAMS_CLAUSE(firstprivate)
 OPENMP_TEAMS_CLAUSE(shared)
 OPENMP_TEAMS_CLAUSE(reduction)
 OPENMP_TEAMS_CLAUSE(num_teams)
 OPENMP_TEAMS_CLAUSE(thread_limit)
 OPENMP_TEAMS_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'ordered'.
 OPENMP_ORDERED_CLAUSE(threads)
 OPENMP_ORDERED_CLAUSE(simd)
 OPENMP_ORDERED_CLAUSE(depend)
 
 // Map types for 'map' clause.
 OPENMP_MAP_KIND(alloc)
 OPENMP_MAP_KIND(to)
 OPENMP_MAP_KIND(from)
 OPENMP_MAP_KIND(tofrom)
 OPENMP_MAP_KIND(delete)
 OPENMP_MAP_KIND(release)
 
 // Map-type-modifiers for 'map' clause.
 OPENMP_MAP_MODIFIER_KIND(always)
 OPENMP_MAP_MODIFIER_KIND(close)
 OPENMP_MAP_MODIFIER_KIND(mapper)
 
 // Modifiers for 'to' clause.
 OPENMP_TO_MODIFIER_KIND(mapper)
 
 // Modifiers for 'from' clause.
 OPENMP_FROM_MODIFIER_KIND(mapper)
 
 // Clauses allowed for OpenMP directive 'taskloop'.
 OPENMP_TASKLOOP_CLAUSE(if)
 OPENMP_TASKLOOP_CLAUSE(shared)
 OPENMP_TASKLOOP_CLAUSE(private)
 OPENMP_TASKLOOP_CLAUSE(firstprivate)
 OPENMP_TASKLOOP_CLAUSE(lastprivate)
 OPENMP_TASKLOOP_CLAUSE(default)
 OPENMP_TASKLOOP_CLAUSE(collapse)
 OPENMP_TASKLOOP_CLAUSE(final)
 OPENMP_TASKLOOP_CLAUSE(untied)
 OPENMP_TASKLOOP_CLAUSE(mergeable)
 OPENMP_TASKLOOP_CLAUSE(priority)
 OPENMP_TASKLOOP_CLAUSE(grainsize)
 OPENMP_TASKLOOP_CLAUSE(nogroup)
 OPENMP_TASKLOOP_CLAUSE(num_tasks)
 OPENMP_TASKLOOP_CLAUSE(reduction)
 OPENMP_TASKLOOP_CLAUSE(in_reduction)
 OPENMP_TASKLOOP_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'taskloop simd'.
 OPENMP_TASKLOOP_SIMD_CLAUSE(if)
 OPENMP_TASKLOOP_SIMD_CLAUSE(shared)
 OPENMP_TASKLOOP_SIMD_CLAUSE(private)
 OPENMP_TASKLOOP_SIMD_CLAUSE(firstprivate)
 OPENMP_TASKLOOP_SIMD_CLAUSE(lastprivate)
 OPENMP_TASKLOOP_SIMD_CLAUSE(default)
 OPENMP_TASKLOOP_SIMD_CLAUSE(collapse)
 OPENMP_TASKLOOP_SIMD_CLAUSE(final)
 OPENMP_TASKLOOP_SIMD_CLAUSE(untied)
 OPENMP_TASKLOOP_SIMD_CLAUSE(mergeable)
 OPENMP_TASKLOOP_SIMD_CLAUSE(priority)
 OPENMP_TASKLOOP_SIMD_CLAUSE(linear)
 OPENMP_TASKLOOP_SIMD_CLAUSE(aligned)
 OPENMP_TASKLOOP_SIMD_CLAUSE(safelen)
 OPENMP_TASKLOOP_SIMD_CLAUSE(simdlen)
 OPENMP_TASKLOOP_SIMD_CLAUSE(grainsize)
 OPENMP_TASKLOOP_SIMD_CLAUSE(nogroup)
 OPENMP_TASKLOOP_SIMD_CLAUSE(num_tasks)
 OPENMP_TASKLOOP_SIMD_CLAUSE(reduction)
 OPENMP_TASKLOOP_SIMD_CLAUSE(in_reduction)
 OPENMP_TASKLOOP_SIMD_CLAUSE(allocate)
 OPENMP_TASKLOOP_SIMD_CLAUSE(nontemporal)
 OPENMP_TASKLOOP_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'master taskloop'.
 OPENMP_MASTER_TASKLOOP_CLAUSE(if)
 OPENMP_MASTER_TASKLOOP_CLAUSE(shared)
 OPENMP_MASTER_TASKLOOP_CLAUSE(private)
 OPENMP_MASTER_TASKLOOP_CLAUSE(firstprivate)
 OPENMP_MASTER_TASKLOOP_CLAUSE(lastprivate)
 OPENMP_MASTER_TASKLOOP_CLAUSE(default)
 OPENMP_MASTER_TASKLOOP_CLAUSE(collapse)
 OPENMP_MASTER_TASKLOOP_CLAUSE(final)
 OPENMP_MASTER_TASKLOOP_CLAUSE(untied)
 OPENMP_MASTER_TASKLOOP_CLAUSE(mergeable)
 OPENMP_MASTER_TASKLOOP_CLAUSE(priority)
 OPENMP_MASTER_TASKLOOP_CLAUSE(grainsize)
 OPENMP_MASTER_TASKLOOP_CLAUSE(nogroup)
 OPENMP_MASTER_TASKLOOP_CLAUSE(num_tasks)
 OPENMP_MASTER_TASKLOOP_CLAUSE(reduction)
 OPENMP_MASTER_TASKLOOP_CLAUSE(in_reduction)
 OPENMP_MASTER_TASKLOOP_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'master taskloop simd'.
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(if)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(shared)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(private)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(firstprivate)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(lastprivate)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(default)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(collapse)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(final)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(untied)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(mergeable)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(priority)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(linear)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(aligned)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(safelen)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(simdlen)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(grainsize)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(nogroup)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(num_tasks)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(reduction)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(in_reduction)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(allocate)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(nontemporal)
 OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'parallel master taskloop'.
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(if)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(shared)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(private)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(firstprivate)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(lastprivate)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(default)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(collapse)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(final)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(untied)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(mergeable)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(priority)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(grainsize)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(nogroup)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(num_tasks)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(reduction)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(allocate)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(num_threads)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(proc_bind)
 OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE(copyin)
 
 // Clauses allowed for OpenMP directive 'parallel master taskloop simd'.
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(if)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(shared)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(private)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(firstprivate)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(lastprivate)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(default)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(collapse)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(final)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(untied)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(mergeable)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(priority)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(grainsize)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(nogroup)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(num_tasks)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(reduction)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(allocate)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(num_threads)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(proc_bind)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(copyin)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(linear)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(aligned)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(safelen)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(simdlen)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(nontemporal)
 OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'critical'.
 OPENMP_CRITICAL_CLAUSE(hint)
 
 // Clauses allowed for OpenMP directive 'distribute'
 OPENMP_DISTRIBUTE_CLAUSE(private)
 OPENMP_DISTRIBUTE_CLAUSE(firstprivate)
 OPENMP_DISTRIBUTE_CLAUSE(lastprivate)
 OPENMP_DISTRIBUTE_CLAUSE(collapse)
 OPENMP_DISTRIBUTE_CLAUSE(dist_schedule)
 OPENMP_DISTRIBUTE_CLAUSE(allocate)
 
 // Static attributes for 'dist_schedule' clause.
 OPENMP_DIST_SCHEDULE_KIND(static)
 
 // Clauses allowed for OpenMP directive 'distribute parallel for'
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(firstprivate)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(lastprivate)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(collapse)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(dist_schedule)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(if)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(num_threads)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(default)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(proc_bind)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(private)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(shared)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(reduction)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(copyin)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(schedule)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(allocate)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'distribute parallel for simd'
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(firstprivate)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(lastprivate)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(collapse)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(dist_schedule)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(if)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(num_threads)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(default)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(proc_bind)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(private)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(shared)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(reduction)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(copyin)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(schedule)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(linear)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(aligned)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(safelen)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(simdlen)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(allocate)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(nontemporal)
 OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'distribute simd'
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(private)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(firstprivate)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(lastprivate)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(collapse)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(dist_schedule)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(linear)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(aligned)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(safelen)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(simdlen)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(reduction)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(allocate)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(if)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(nontemporal)
 OPENMP_DISTRIBUTE_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'target parallel for simd'.
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(if)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(device)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(map)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(private)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(firstprivate)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(lastprivate)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(nowait)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(depend)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(defaultmap)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(num_threads)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(default)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(proc_bind)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(shared)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(reduction)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(collapse)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(schedule)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(ordered)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(linear)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(safelen)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(simdlen)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(aligned)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(is_device_ptr)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(allocate)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(nontemporal)
 OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'target simd'.
 OPENMP_TARGET_SIMD_CLAUSE(if)
 OPENMP_TARGET_SIMD_CLAUSE(device)
 OPENMP_TARGET_SIMD_CLAUSE(map)
 OPENMP_TARGET_SIMD_CLAUSE(private)
 OPENMP_TARGET_SIMD_CLAUSE(nowait)
 OPENMP_TARGET_SIMD_CLAUSE(depend)
 OPENMP_TARGET_SIMD_CLAUSE(defaultmap)
 OPENMP_TARGET_SIMD_CLAUSE(firstprivate)
 OPENMP_TARGET_SIMD_CLAUSE(is_device_ptr)
 OPENMP_TARGET_SIMD_CLAUSE(lastprivate)
 OPENMP_TARGET_SIMD_CLAUSE(linear)
 OPENMP_TARGET_SIMD_CLAUSE(aligned)
 OPENMP_TARGET_SIMD_CLAUSE(safelen)
 OPENMP_TARGET_SIMD_CLAUSE(simdlen)
 OPENMP_TARGET_SIMD_CLAUSE(collapse)
 OPENMP_TARGET_SIMD_CLAUSE(reduction)
 OPENMP_TARGET_SIMD_CLAUSE(allocate)
 OPENMP_TARGET_SIMD_CLAUSE(nontemporal)
 OPENMP_TARGET_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'teams distribute'.
 OPENMP_TEAMS_DISTRIBUTE_CLAUSE(default)
 OPENMP_TEAMS_DISTRIBUTE_CLAUSE(private)
 OPENMP_TEAMS_DISTRIBUTE_CLAUSE(firstprivate)
 OPENMP_TEAMS_DISTRIBUTE_CLAUSE(shared)
 OPENMP_TEAMS_DISTRIBUTE_CLAUSE(reduction)
 OPENMP_TEAMS_DISTRIBUTE_CLAUSE(num_teams)
 OPENMP_TEAMS_DISTRIBUTE_CLAUSE(thread_limit)
 OPENMP_TEAMS_DISTRIBUTE_CLAUSE(lastprivate)
 OPENMP_TEAMS_DISTRIBUTE_CLAUSE(collapse)
 OPENMP_TEAMS_DISTRIBUTE_CLAUSE(dist_schedule)
 OPENMP_TEAMS_DISTRIBUTE_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'teams distribute simd'
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(default)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(private)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(firstprivate)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(shared)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(reduction)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(num_teams)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(thread_limit)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(lastprivate)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(collapse)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(dist_schedule)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(linear)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(aligned)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(safelen)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(simdlen)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(allocate)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(if)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(nontemporal)
 OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'teams distribute parallel for simd'
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(firstprivate)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(lastprivate)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(collapse)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(dist_schedule)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(if)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(num_threads)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(default)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(proc_bind)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(private)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(shared)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(reduction)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(schedule)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(linear)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(aligned)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(safelen)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(simdlen)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(num_teams)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(thread_limit)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(allocate)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(nontemporal)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'teams distribute parallel for'
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(firstprivate)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(lastprivate)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(collapse)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(dist_schedule)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(if)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(num_threads)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(default)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(proc_bind)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(private)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(shared)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(reduction)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(schedule)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(num_teams)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(thread_limit)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(copyin)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(allocate)
 OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'target teams'.
 OPENMP_TARGET_TEAMS_CLAUSE(if)
 OPENMP_TARGET_TEAMS_CLAUSE(device)
 OPENMP_TARGET_TEAMS_CLAUSE(map)
 OPENMP_TARGET_TEAMS_CLAUSE(private)
 OPENMP_TARGET_TEAMS_CLAUSE(nowait)
 OPENMP_TARGET_TEAMS_CLAUSE(depend)
 OPENMP_TARGET_TEAMS_CLAUSE(defaultmap)
 OPENMP_TARGET_TEAMS_CLAUSE(firstprivate)
 OPENMP_TARGET_TEAMS_CLAUSE(is_device_ptr)
 OPENMP_TARGET_TEAMS_CLAUSE(default)
 OPENMP_TARGET_TEAMS_CLAUSE(shared)
 OPENMP_TARGET_TEAMS_CLAUSE(reduction)
 OPENMP_TARGET_TEAMS_CLAUSE(num_teams)
 OPENMP_TARGET_TEAMS_CLAUSE(thread_limit)
 OPENMP_TARGET_TEAMS_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'target teams distribute'.
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(if)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(device)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(map)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(private)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(nowait)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(depend)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(defaultmap)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(firstprivate)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(is_device_ptr)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(default)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(shared)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(reduction)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(num_teams)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(thread_limit)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(lastprivate)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(collapse)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(dist_schedule)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'target teams distribute parallel for'.
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(if)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(device)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(map)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(private)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(nowait)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(depend)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(defaultmap)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(firstprivate)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(is_device_ptr)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(default)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(shared)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(reduction)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(num_teams)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(thread_limit)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(lastprivate)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(collapse)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(dist_schedule)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(num_threads)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(proc_bind)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(schedule)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(allocate)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive
 // 'target teams distribute parallel for simd'.
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(if)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(device)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(map)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(private)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(nowait)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(depend)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(defaultmap)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(firstprivate)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(is_device_ptr)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(default)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(shared)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(reduction)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(num_teams)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(thread_limit)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(lastprivate)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(collapse)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(dist_schedule)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(num_threads)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(proc_bind)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(schedule)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(linear)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(aligned)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(safelen)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(simdlen)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(allocate)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(nontemporal)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'target teams distribute simd'.
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(if)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(device)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(map)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(private)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(nowait)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(depend)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(defaultmap)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(firstprivate)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(lastprivate)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(is_device_ptr)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(shared)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(reduction)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(num_teams)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(thread_limit)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(collapse)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(dist_schedule)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(linear)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(aligned)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(safelen)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(simdlen)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(allocate)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(nontemporal)
 OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE(order)
 
 // Clauses allowed for OpenMP directive 'taskgroup'.
 OPENMP_TASKGROUP_CLAUSE(task_reduction)
 OPENMP_TASKGROUP_CLAUSE(allocate)
 
 // Clauses allowed for OpenMP directive 'declare mapper'.
 OPENMP_DECLARE_MAPPER_CLAUSE(map)
 
 // Device types for 'device_type' clause.
 OPENMP_DEVICE_TYPE_KIND(host)
 OPENMP_DEVICE_TYPE_KIND(nohost)
 OPENMP_DEVICE_TYPE_KIND(any)
 
 // Clauses allowed for OpenMP directive 'declare variant'.
 OPENMP_DECLARE_VARIANT_CLAUSE(match)
 
 // Type of the 'lastprivate' clause.
 OPENMP_LASTPRIVATE_KIND(conditional)
 
 // Type of the 'order' clause.
 OPENMP_ORDER_KIND(concurrent)
 
 // Clauses allowed for OpenMP directive 'flush'.
 OPENMP_FLUSH_CLAUSE(acq_rel)
 OPENMP_FLUSH_CLAUSE(acquire)
 OPENMP_FLUSH_CLAUSE(release)
 
 // Clauses allowed for OpenMP directive 'depobj'.
 OPENMP_DEPOBJ_CLAUSE(depend)
 OPENMP_DEPOBJ_CLAUSE(destroy)
 OPENMP_DEPOBJ_CLAUSE(update)
 
+#undef OPENMP_DEVICE_MODIFIER
 #undef OPENMP_DEPOBJ_CLAUSE
 #undef OPENMP_FLUSH_CLAUSE
 #undef OPENMP_ORDER_KIND
 #undef OPENMP_LASTPRIVATE_KIND
 #undef OPENMP_DECLARE_VARIANT_CLAUSE
 #undef OPENMP_DEVICE_TYPE_KIND
 #undef OPENMP_ALLOCATE_CLAUSE
 #undef OPENMP_DECLARE_MAPPER_CLAUSE
 #undef OPENMP_TASKGROUP_CLAUSE
 #undef OPENMP_PARALLEL_MASTER_TASKLOOP_SIMD_CLAUSE
 #undef OPENMP_PARALLEL_MASTER_TASKLOOP_CLAUSE
 #undef OPENMP_MASTER_TASKLOOP_SIMD_CLAUSE
 #undef OPENMP_MASTER_TASKLOOP_CLAUSE
 #undef OPENMP_TASKLOOP_SIMD_CLAUSE
 #undef OPENMP_TASKLOOP_CLAUSE
 #undef OPENMP_LINEAR_KIND
 #undef OPENMP_DEPEND_KIND
 #undef OPENMP_SCHEDULE_MODIFIER
 #undef OPENMP_SCHEDULE_KIND
 #undef OPENMP_CLAUSE
 #undef OPENMP_CRITICAL_CLAUSE
 #undef OPENMP_ORDERED_CLAUSE
 #undef OPENMP_CANCEL_CLAUSE
 #undef OPENMP_SINGLE_CLAUSE
 #undef OPENMP_SECTIONS_CLAUSE
 #undef OPENMP_PARALLEL_CLAUSE
 #undef OPENMP_PARALLEL_FOR_CLAUSE
 #undef OPENMP_PARALLEL_FOR_SIMD_CLAUSE
 #undef OPENMP_PARALLEL_MASTER_CLAUSE
 #undef OPENMP_PARALLEL_SECTIONS_CLAUSE
 #undef OPENMP_TASK_CLAUSE
 #undef OPENMP_ATOMIC_CLAUSE
 #undef OPENMP_TARGET_CLAUSE
 #undef OPENMP_REQUIRES_CLAUSE
 #undef OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND
 #undef OPENMP_TARGET_DATA_CLAUSE
 #undef OPENMP_TARGET_ENTER_DATA_CLAUSE
 #undef OPENMP_TARGET_EXIT_DATA_CLAUSE
 #undef OPENMP_TARGET_PARALLEL_CLAUSE
 #undef OPENMP_TARGET_PARALLEL_FOR_CLAUSE
 #undef OPENMP_TEAMS_CLAUSE
 #undef OPENMP_SIMD_CLAUSE
 #undef OPENMP_FOR_CLAUSE
 #undef OPENMP_FOR_SIMD_CLAUSE
 #undef OPENMP_MAP_KIND
 #undef OPENMP_MAP_MODIFIER_KIND
 #undef OPENMP_TO_MODIFIER_KIND
 #undef OPENMP_FROM_MODIFIER_KIND
 #undef OPENMP_DISTRIBUTE_CLAUSE
 #undef OPENMP_DIST_SCHEDULE_KIND
 #undef OPENMP_DEFAULTMAP_KIND
 #undef OPENMP_DEFAULTMAP_MODIFIER
 #undef OPENMP_TARGET_UPDATE_CLAUSE
 #undef OPENMP_DISTRIBUTE_PARALLEL_FOR_CLAUSE
 #undef OPENMP_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE
 #undef OPENMP_DISTRIBUTE_SIMD_CLAUSE
 #undef OPENMP_TARGET_PARALLEL_FOR_SIMD_CLAUSE
 #undef OPENMP_TARGET_SIMD_CLAUSE
 #undef OPENMP_TEAMS_DISTRIBUTE_CLAUSE
 #undef OPENMP_TEAMS_DISTRIBUTE_SIMD_CLAUSE
 #undef OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE
 #undef OPENMP_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE
 #undef OPENMP_TARGET_TEAMS_CLAUSE
 #undef OPENMP_TARGET_TEAMS_DISTRIBUTE_CLAUSE
 #undef OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_CLAUSE
 #undef OPENMP_TARGET_TEAMS_DISTRIBUTE_PARALLEL_FOR_SIMD_CLAUSE
 #undef OPENMP_TARGET_TEAMS_DISTRIBUTE_SIMD_CLAUSE
diff --git a/clang/include/clang/Basic/OpenMPKinds.h b/clang/include/clang/Basic/OpenMPKinds.h
index 43196663c45f..46eeffe999d9 100644
--- a/clang/include/clang/Basic/OpenMPKinds.h
+++ b/clang/include/clang/Basic/OpenMPKinds.h
@@ -1,278 +1,285 @@
 //===--- OpenMPKinds.h - OpenMP enums ---------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
 /// Defines some OpenMP-specific enums and functions.
 ///
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_BASIC_OPENMPKINDS_H
 #define LLVM_CLANG_BASIC_OPENMPKINDS_H
 
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Frontend/OpenMP/OMPConstants.h"
 
 namespace clang {
 
 /// OpenMP directives.
 using OpenMPDirectiveKind = llvm::omp::Directive;
 
 /// OpenMP clauses.
 enum OpenMPClauseKind {
 #define OPENMP_CLAUSE(Name, Class) \
   OMPC_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_threadprivate,
   OMPC_uniform,
   OMPC_device_type,
   OMPC_match,
   OMPC_unknown
 };
 
 /// OpenMP attributes for 'schedule' clause.
 enum OpenMPScheduleClauseKind {
 #define OPENMP_SCHEDULE_KIND(Name) \
   OMPC_SCHEDULE_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_SCHEDULE_unknown
 };
 
 /// OpenMP modifiers for 'schedule' clause.
 enum OpenMPScheduleClauseModifier {
   OMPC_SCHEDULE_MODIFIER_unknown = OMPC_SCHEDULE_unknown,
 #define OPENMP_SCHEDULE_MODIFIER(Name) \
   OMPC_SCHEDULE_MODIFIER_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_SCHEDULE_MODIFIER_last
 };
 
+/// OpenMP modifiers for 'device' clause.
+enum OpenMPDeviceClauseModifier {
+#define OPENMP_DEVICE_MODIFIER(Name) OMPC_DEVICE_##Name,
+#include "clang/Basic/OpenMPKinds.def"
+  OMPC_DEVICE_unknown,
+};
+
 /// OpenMP attributes for 'depend' clause.
 enum OpenMPDependClauseKind {
 #define OPENMP_DEPEND_KIND(Name) \
   OMPC_DEPEND_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_DEPEND_unknown
 };
 
 /// OpenMP attributes for 'linear' clause.
 enum OpenMPLinearClauseKind {
 #define OPENMP_LINEAR_KIND(Name) \
   OMPC_LINEAR_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_LINEAR_unknown
 };
 
 /// OpenMP mapping kind for 'map' clause.
 enum OpenMPMapClauseKind {
 #define OPENMP_MAP_KIND(Name) \
   OMPC_MAP_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_MAP_unknown
 };
 
 /// OpenMP modifier kind for 'map' clause.
 enum OpenMPMapModifierKind {
   OMPC_MAP_MODIFIER_unknown = OMPC_MAP_unknown,
 #define OPENMP_MAP_MODIFIER_KIND(Name) \
   OMPC_MAP_MODIFIER_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_MAP_MODIFIER_last
 };
 
 /// OpenMP modifier kind for 'to' clause.
 enum OpenMPToModifierKind {
 #define OPENMP_TO_MODIFIER_KIND(Name) \
   OMPC_TO_MODIFIER_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_TO_MODIFIER_unknown
 };
 
 /// OpenMP modifier kind for 'from' clause.
 enum OpenMPFromModifierKind {
 #define OPENMP_FROM_MODIFIER_KIND(Name) \
   OMPC_FROM_MODIFIER_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_FROM_MODIFIER_unknown
 };
 
 /// OpenMP attributes for 'dist_schedule' clause.
 enum OpenMPDistScheduleClauseKind {
 #define OPENMP_DIST_SCHEDULE_KIND(Name) OMPC_DIST_SCHEDULE_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_DIST_SCHEDULE_unknown
 };
 
 /// OpenMP attributes for 'defaultmap' clause.
 enum OpenMPDefaultmapClauseKind {
 #define OPENMP_DEFAULTMAP_KIND(Name) \
   OMPC_DEFAULTMAP_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_DEFAULTMAP_unknown
 };
 
 /// OpenMP modifiers for 'defaultmap' clause.
 enum OpenMPDefaultmapClauseModifier {
   OMPC_DEFAULTMAP_MODIFIER_unknown = OMPC_DEFAULTMAP_unknown,
 #define OPENMP_DEFAULTMAP_MODIFIER(Name) \
   OMPC_DEFAULTMAP_MODIFIER_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_DEFAULTMAP_MODIFIER_last
 };
 
 /// OpenMP attributes for 'atomic_default_mem_order' clause.
 enum OpenMPAtomicDefaultMemOrderClauseKind {
 #define OPENMP_ATOMIC_DEFAULT_MEM_ORDER_KIND(Name)  \
   OMPC_ATOMIC_DEFAULT_MEM_ORDER_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_ATOMIC_DEFAULT_MEM_ORDER_unknown
 };
 
 /// OpenMP device type for 'device_type' clause.
 enum OpenMPDeviceType {
 #define OPENMP_DEVICE_TYPE_KIND(Name) \
   OMPC_DEVICE_TYPE_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_DEVICE_TYPE_unknown
 };
 
 /// OpenMP 'lastprivate' clause modifier.
 enum OpenMPLastprivateModifier {
 #define OPENMP_LASTPRIVATE_KIND(Name) OMPC_LASTPRIVATE_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_LASTPRIVATE_unknown,
 };
 
 /// OpenMP attributes for 'order' clause.
 enum OpenMPOrderClauseKind {
 #define OPENMP_ORDER_KIND(Name) OMPC_ORDER_##Name,
 #include "clang/Basic/OpenMPKinds.def"
   OMPC_ORDER_unknown,
 };
 
 /// Scheduling data for loop-based OpenMP directives.
 struct OpenMPScheduleTy final {
   OpenMPScheduleClauseKind Schedule = OMPC_SCHEDULE_unknown;
   OpenMPScheduleClauseModifier M1 = OMPC_SCHEDULE_MODIFIER_unknown;
   OpenMPScheduleClauseModifier M2 = OMPC_SCHEDULE_MODIFIER_unknown;
 };
 
 OpenMPClauseKind getOpenMPClauseKind(llvm::StringRef Str);
 const char *getOpenMPClauseName(OpenMPClauseKind Kind);
 
 unsigned getOpenMPSimpleClauseType(OpenMPClauseKind Kind, llvm::StringRef Str);
 const char *getOpenMPSimpleClauseTypeName(OpenMPClauseKind Kind, unsigned Type);
 
 bool isAllowedClauseForDirective(OpenMPDirectiveKind DKind,
                                  OpenMPClauseKind CKind,
                                  unsigned OpenMPVersion);
 
 /// Checks if the specified directive is a directive with an associated
 /// loop construct.
 /// \param DKind Specified directive.
 /// \return true - the directive is a loop-associated directive like 'omp simd'
 /// or 'omp for' directive, otherwise - false.
 bool isOpenMPLoopDirective(OpenMPDirectiveKind DKind);
 
 /// Checks if the specified directive is a worksharing directive.
 /// \param DKind Specified directive.
 /// \return true - the directive is a worksharing directive like 'omp for',
 /// otherwise - false.
 bool isOpenMPWorksharingDirective(OpenMPDirectiveKind DKind);
 
 /// Checks if the specified directive is a taskloop directive.
 /// \param DKind Specified directive.
 /// \return true - the directive is a worksharing directive like 'omp taskloop',
 /// otherwise - false.
 bool isOpenMPTaskLoopDirective(OpenMPDirectiveKind DKind);
 
 /// Checks if the specified directive is a parallel-kind directive.
 /// \param DKind Specified directive.
 /// \return true - the directive is a parallel-like directive like 'omp
 /// parallel', otherwise - false.
 bool isOpenMPParallelDirective(OpenMPDirectiveKind DKind);
 
 /// Checks if the specified directive is a target code offload directive.
 /// \param DKind Specified directive.
 /// \return true - the directive is a target code offload directive like
 /// 'omp target', 'omp target parallel', 'omp target xxx'
 /// otherwise - false.
 bool isOpenMPTargetExecutionDirective(OpenMPDirectiveKind DKind);
 
 /// Checks if the specified directive is a target data offload directive.
 /// \param DKind Specified directive.
 /// \return true - the directive is a target data offload directive like
 /// 'omp target data', 'omp target update', 'omp target enter data',
 /// 'omp target exit data'
 /// otherwise - false.
 bool isOpenMPTargetDataManagementDirective(OpenMPDirectiveKind DKind);
 
 /// Checks if the specified composite/combined directive constitutes a teams
 /// directive in the outermost nest.  For example
 /// 'omp teams distribute' or 'omp teams distribute parallel for'.
 /// \param DKind Specified directive.
 /// \return true - the directive has teams on the outermost nest, otherwise -
 /// false.
 bool isOpenMPNestingTeamsDirective(OpenMPDirectiveKind DKind);
 
 /// Checks if the specified directive is a teams-kind directive.  For example,
 /// 'omp teams distribute' or 'omp target teams'.
 /// \param DKind Specified directive.
 /// \return true - the directive is a teams-like directive, otherwise - false.
 bool isOpenMPTeamsDirective(OpenMPDirectiveKind DKind);
 
 /// Checks if the specified directive is a simd directive.
 /// \param DKind Specified directive.
 /// \return true - the directive is a simd directive like 'omp simd',
 /// otherwise - false.
 bool isOpenMPSimdDirective(OpenMPDirectiveKind DKind);
 
 /// Checks if the specified directive is a distribute directive.
 /// \param DKind Specified directive.
 /// \return true - the directive is a distribute-directive like 'omp
 /// distribute',
 /// otherwise - false.
 bool isOpenMPDistributeDirective(OpenMPDirectiveKind DKind);
 
 /// Checks if the specified composite/combined directive constitutes a
 /// distribute directive in the outermost nest.  For example,
 /// 'omp distribute parallel for' or 'omp distribute'.
 /// \param DKind Specified directive.
 /// \return true - the directive has distribute on the outermost nest.
 /// otherwise - false.
 bool isOpenMPNestingDistributeDirective(OpenMPDirectiveKind DKind);
 
 /// Checks if the specified clause is one of private clauses like
 /// 'private', 'firstprivate', 'reduction' etc..
 /// \param Kind Clause kind.
 /// \return true - the clause is a private clause, otherwise - false.
 bool isOpenMPPrivate(OpenMPClauseKind Kind);
 
 /// Checks if the specified clause is one of threadprivate clauses like
 /// 'threadprivate', 'copyin' or 'copyprivate'.
 /// \param Kind Clause kind.
 /// \return true - the clause is a threadprivate clause, otherwise - false.
 bool isOpenMPThreadPrivate(OpenMPClauseKind Kind);
 
 /// Checks if the specified directive kind is one of tasking directives - task,
 /// taskloop, taksloop simd, master taskloop, parallel master taskloop, master
 /// taskloop simd, or parallel master taskloop simd.
 bool isOpenMPTaskingDirective(OpenMPDirectiveKind Kind);
 
 /// Checks if the specified directive kind is one of the composite or combined
 /// directives that need loop bound sharing across loops outlined in nested
 /// functions
 bool isOpenMPLoopBoundSharingDirective(OpenMPDirectiveKind Kind);
 
 /// Return the captured regions of an OpenMP directive.
 void getOpenMPCaptureRegions(
     llvm::SmallVectorImpl<OpenMPDirectiveKind> &CaptureRegions,
     OpenMPDirectiveKind DKind);
 }
 
 #endif
 
diff --git a/clang/include/clang/Parse/Parser.h b/clang/include/clang/Parse/Parser.h
index 85844e2edb07..a9c68a2e231e 100644
--- a/clang/include/clang/Parse/Parser.h
+++ b/clang/include/clang/Parse/Parser.h
@@ -1,3229 +1,3231 @@
 //===--- Parser.h - C Language Parser ---------------------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 //  This file defines the Parser interface.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_PARSE_PARSER_H
 #define LLVM_CLANG_PARSE_PARSER_H
 
 #include "clang/AST/OpenMPClause.h"
 #include "clang/AST/Availability.h"
 #include "clang/Basic/BitmaskEnum.h"
 #include "clang/Basic/OpenMPKinds.h"
 #include "clang/Basic/OperatorPrecedence.h"
 #include "clang/Basic/Specifiers.h"
 #include "clang/Lex/CodeCompletionHandler.h"
 #include "clang/Lex/Preprocessor.h"
 #include "clang/Sema/DeclSpec.h"
 #include "clang/Sema/Sema.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/Support/Compiler.h"
 #include "llvm/Support/PrettyStackTrace.h"
 #include "llvm/Support/SaveAndRestore.h"
 #include <memory>
 #include <stack>
 
 namespace clang {
   class PragmaHandler;
   class Scope;
   class BalancedDelimiterTracker;
   class CorrectionCandidateCallback;
   class DeclGroupRef;
   class DiagnosticBuilder;
   struct LoopHint;
   class Parser;
   class ParsingDeclRAIIObject;
   class ParsingDeclSpec;
   class ParsingDeclarator;
   class ParsingFieldDeclarator;
   class ColonProtectionRAIIObject;
   class InMessageExpressionRAIIObject;
   class PoisonSEHIdentifiersRAIIObject;
   class OMPClause;
   class ObjCTypeParamList;
   class ObjCTypeParameter;
 
 /// Parser - This implements a parser for the C family of languages.  After
 /// parsing units of the grammar, productions are invoked to handle whatever has
 /// been read.
 ///
 class Parser : public CodeCompletionHandler {
   friend class ColonProtectionRAIIObject;
   friend class ParsingOpenMPDirectiveRAII;
   friend class InMessageExpressionRAIIObject;
   friend class PoisonSEHIdentifiersRAIIObject;
   friend class ObjCDeclContextSwitch;
   friend class ParenBraceBracketBalancer;
   friend class BalancedDelimiterTracker;
 
   Preprocessor &PP;
 
   /// Tok - The current token we are peeking ahead.  All parsing methods assume
   /// that this is valid.
   Token Tok;
 
   // PrevTokLocation - The location of the token we previously
   // consumed. This token is used for diagnostics where we expected to
   // see a token following another token (e.g., the ';' at the end of
   // a statement).
   SourceLocation PrevTokLocation;
 
   /// Tracks an expected type for the current token when parsing an expression.
   /// Used by code completion for ranking.
   PreferredTypeBuilder PreferredType;
 
   unsigned short ParenCount = 0, BracketCount = 0, BraceCount = 0;
   unsigned short MisplacedModuleBeginCount = 0;
 
   /// Actions - These are the callbacks we invoke as we parse various constructs
   /// in the file.
   Sema &Actions;
 
   DiagnosticsEngine &Diags;
 
   /// ScopeCache - Cache scopes to reduce malloc traffic.
   enum { ScopeCacheSize = 16 };
   unsigned NumCachedScopes;
   Scope *ScopeCache[ScopeCacheSize];
 
   /// Identifiers used for SEH handling in Borland. These are only
   /// allowed in particular circumstances
   // __except block
   IdentifierInfo *Ident__exception_code,
                  *Ident___exception_code,
                  *Ident_GetExceptionCode;
   // __except filter expression
   IdentifierInfo *Ident__exception_info,
                  *Ident___exception_info,
                  *Ident_GetExceptionInfo;
   // __finally
   IdentifierInfo *Ident__abnormal_termination,
                  *Ident___abnormal_termination,
                  *Ident_AbnormalTermination;
 
   /// Contextual keywords for Microsoft extensions.
   IdentifierInfo *Ident__except;
   mutable IdentifierInfo *Ident_sealed;
 
   /// Ident_super - IdentifierInfo for "super", to support fast
   /// comparison.
   IdentifierInfo *Ident_super;
   /// Ident_vector, Ident_bool - cached IdentifierInfos for "vector" and
   /// "bool" fast comparison.  Only present if AltiVec or ZVector are enabled.
   IdentifierInfo *Ident_vector;
   IdentifierInfo *Ident_bool;
   /// Ident_pixel - cached IdentifierInfos for "pixel" fast comparison.
   /// Only present if AltiVec enabled.
   IdentifierInfo *Ident_pixel;
 
   /// Objective-C contextual keywords.
   IdentifierInfo *Ident_instancetype;
 
   /// Identifier for "introduced".
   IdentifierInfo *Ident_introduced;
 
   /// Identifier for "deprecated".
   IdentifierInfo *Ident_deprecated;
 
   /// Identifier for "obsoleted".
   IdentifierInfo *Ident_obsoleted;
 
   /// Identifier for "unavailable".
   IdentifierInfo *Ident_unavailable;
 
   /// Identifier for "message".
   IdentifierInfo *Ident_message;
 
   /// Identifier for "strict".
   IdentifierInfo *Ident_strict;
 
   /// Identifier for "replacement".
   IdentifierInfo *Ident_replacement;
 
   /// Identifiers used by the 'external_source_symbol' attribute.
   IdentifierInfo *Ident_language, *Ident_defined_in,
       *Ident_generated_declaration;
 
   /// C++11 contextual keywords.
   mutable IdentifierInfo *Ident_final;
   mutable IdentifierInfo *Ident_GNU_final;
   mutable IdentifierInfo *Ident_override;
 
   // C++2a contextual keywords.
   mutable IdentifierInfo *Ident_import;
   mutable IdentifierInfo *Ident_module;
 
   // C++ type trait keywords that can be reverted to identifiers and still be
   // used as type traits.
   llvm::SmallDenseMap<IdentifierInfo *, tok::TokenKind> RevertibleTypeTraits;
 
   std::unique_ptr<PragmaHandler> AlignHandler;
   std::unique_ptr<PragmaHandler> GCCVisibilityHandler;
   std::unique_ptr<PragmaHandler> OptionsHandler;
   std::unique_ptr<PragmaHandler> PackHandler;
   std::unique_ptr<PragmaHandler> MSStructHandler;
   std::unique_ptr<PragmaHandler> UnusedHandler;
   std::unique_ptr<PragmaHandler> WeakHandler;
   std::unique_ptr<PragmaHandler> RedefineExtnameHandler;
   std::unique_ptr<PragmaHandler> FPContractHandler;
   std::unique_ptr<PragmaHandler> OpenCLExtensionHandler;
   std::unique_ptr<PragmaHandler> OpenMPHandler;
   std::unique_ptr<PragmaHandler> PCSectionHandler;
   std::unique_ptr<PragmaHandler> MSCommentHandler;
   std::unique_ptr<PragmaHandler> MSDetectMismatchHandler;
   std::unique_ptr<PragmaHandler> MSPointersToMembers;
   std::unique_ptr<PragmaHandler> MSVtorDisp;
   std::unique_ptr<PragmaHandler> MSInitSeg;
   std::unique_ptr<PragmaHandler> MSDataSeg;
   std::unique_ptr<PragmaHandler> MSBSSSeg;
   std::unique_ptr<PragmaHandler> MSConstSeg;
   std::unique_ptr<PragmaHandler> MSCodeSeg;
   std::unique_ptr<PragmaHandler> MSSection;
   std::unique_ptr<PragmaHandler> MSRuntimeChecks;
   std::unique_ptr<PragmaHandler> MSIntrinsic;
   std::unique_ptr<PragmaHandler> MSOptimize;
   std::unique_ptr<PragmaHandler> CUDAForceHostDeviceHandler;
   std::unique_ptr<PragmaHandler> OptimizeHandler;
   std::unique_ptr<PragmaHandler> LoopHintHandler;
   std::unique_ptr<PragmaHandler> UnrollHintHandler;
   std::unique_ptr<PragmaHandler> NoUnrollHintHandler;
   std::unique_ptr<PragmaHandler> UnrollAndJamHintHandler;
   std::unique_ptr<PragmaHandler> NoUnrollAndJamHintHandler;
   std::unique_ptr<PragmaHandler> FPHandler;
   std::unique_ptr<PragmaHandler> STDCFENVHandler;
   std::unique_ptr<PragmaHandler> STDCCXLIMITHandler;
   std::unique_ptr<PragmaHandler> STDCUnknownHandler;
   std::unique_ptr<PragmaHandler> AttributePragmaHandler;
   std::unique_ptr<PragmaHandler> MaxTokensHerePragmaHandler;
   std::unique_ptr<PragmaHandler> MaxTokensTotalPragmaHandler;
 
   std::unique_ptr<CommentHandler> CommentSemaHandler;
 
   /// Whether the '>' token acts as an operator or not. This will be
   /// true except when we are parsing an expression within a C++
   /// template argument list, where the '>' closes the template
   /// argument list.
   bool GreaterThanIsOperator;
 
   /// ColonIsSacred - When this is false, we aggressively try to recover from
   /// code like "foo : bar" as if it were a typo for "foo :: bar".  This is not
   /// safe in case statements and a few other things.  This is managed by the
   /// ColonProtectionRAIIObject RAII object.
   bool ColonIsSacred;
 
   /// Parsing OpenMP directive mode.
   bool OpenMPDirectiveParsing = false;
 
   /// When true, we are directly inside an Objective-C message
   /// send expression.
   ///
   /// This is managed by the \c InMessageExpressionRAIIObject class, and
   /// should not be set directly.
   bool InMessageExpression;
 
   /// Gets set to true after calling ProduceSignatureHelp, it is for a
   /// workaround to make sure ProduceSignatureHelp is only called at the deepest
   /// function call.
   bool CalledSignatureHelp = false;
 
   /// The "depth" of the template parameters currently being parsed.
   unsigned TemplateParameterDepth;
 
   /// RAII class that manages the template parameter depth.
   class TemplateParameterDepthRAII {
     unsigned &Depth;
     unsigned AddedLevels;
   public:
     explicit TemplateParameterDepthRAII(unsigned &Depth)
       : Depth(Depth), AddedLevels(0) {}
 
     ~TemplateParameterDepthRAII() {
       Depth -= AddedLevels;
     }
 
     void operator++() {
       ++Depth;
       ++AddedLevels;
     }
     void addDepth(unsigned D) {
       Depth += D;
       AddedLevels += D;
     }
     void setAddedDepth(unsigned D) {
       Depth = Depth - AddedLevels + D;
       AddedLevels = D;
     }
 
     unsigned getDepth() const { return Depth; }
     unsigned getOriginalDepth() const { return Depth - AddedLevels; }
   };
 
   /// Factory object for creating ParsedAttr objects.
   AttributeFactory AttrFactory;
 
   /// Gathers and cleans up TemplateIdAnnotations when parsing of a
   /// top-level declaration is finished.
   SmallVector<TemplateIdAnnotation *, 16> TemplateIds;
 
   /// Identifiers which have been declared within a tentative parse.
   SmallVector<IdentifierInfo *, 8> TentativelyDeclaredIdentifiers;
 
   /// Tracker for '<' tokens that might have been intended to be treated as an
   /// angle bracket instead of a less-than comparison.
   ///
   /// This happens when the user intends to form a template-id, but typoes the
   /// template-name or forgets a 'template' keyword for a dependent template
   /// name.
   ///
   /// We track these locations from the point where we see a '<' with a
   /// name-like expression on its left until we see a '>' or '>>' that might
   /// match it.
   struct AngleBracketTracker {
     /// Flags used to rank candidate template names when there is more than one
     /// '<' in a scope.
     enum Priority : unsigned short {
       /// A non-dependent name that is a potential typo for a template name.
       PotentialTypo = 0x0,
       /// A dependent name that might instantiate to a template-name.
       DependentName = 0x2,
 
       /// A space appears before the '<' token.
       SpaceBeforeLess = 0x0,
       /// No space before the '<' token
       NoSpaceBeforeLess = 0x1,
 
       LLVM_MARK_AS_BITMASK_ENUM(/*LargestValue*/ DependentName)
     };
 
     struct Loc {
       Expr *TemplateName;
       SourceLocation LessLoc;
       AngleBracketTracker::Priority Priority;
       unsigned short ParenCount, BracketCount, BraceCount;
 
       bool isActive(Parser &P) const {
         return P.ParenCount == ParenCount && P.BracketCount == BracketCount &&
                P.BraceCount == BraceCount;
       }
 
       bool isActiveOrNested(Parser &P) const {
         return isActive(P) || P.ParenCount > ParenCount ||
                P.BracketCount > BracketCount || P.BraceCount > BraceCount;
       }
     };
 
     SmallVector<Loc, 8> Locs;
 
     /// Add an expression that might have been intended to be a template name.
     /// In the case of ambiguity, we arbitrarily select the innermost such
     /// expression, for example in 'foo < bar < baz', 'bar' is the current
     /// candidate. No attempt is made to track that 'foo' is also a candidate
     /// for the case where we see a second suspicious '>' token.
     void add(Parser &P, Expr *TemplateName, SourceLocation LessLoc,
              Priority Prio) {
       if (!Locs.empty() && Locs.back().isActive(P)) {
         if (Locs.back().Priority <= Prio) {
           Locs.back().TemplateName = TemplateName;
           Locs.back().LessLoc = LessLoc;
           Locs.back().Priority = Prio;
         }
       } else {
         Locs.push_back({TemplateName, LessLoc, Prio,
                         P.ParenCount, P.BracketCount, P.BraceCount});
       }
     }
 
     /// Mark the current potential missing template location as having been
     /// handled (this happens if we pass a "corresponding" '>' or '>>' token
     /// or leave a bracket scope).
     void clear(Parser &P) {
       while (!Locs.empty() && Locs.back().isActiveOrNested(P))
         Locs.pop_back();
     }
 
     /// Get the current enclosing expression that might hve been intended to be
     /// a template name.
     Loc *getCurrent(Parser &P) {
       if (!Locs.empty() && Locs.back().isActive(P))
         return &Locs.back();
       return nullptr;
     }
   };
 
   AngleBracketTracker AngleBrackets;
 
   IdentifierInfo *getSEHExceptKeyword();
 
   /// True if we are within an Objective-C container while parsing C-like decls.
   ///
   /// This is necessary because Sema thinks we have left the container
   /// to parse the C-like decls, meaning Actions.getObjCDeclContext() will
   /// be NULL.
   bool ParsingInObjCContainer;
 
   /// Whether to skip parsing of function bodies.
   ///
   /// This option can be used, for example, to speed up searches for
   /// declarations/definitions when indexing.
   bool SkipFunctionBodies;
 
   /// The location of the expression statement that is being parsed right now.
   /// Used to determine if an expression that is being parsed is a statement or
   /// just a regular sub-expression.
   SourceLocation ExprStatementTokLoc;
 
   /// Flags describing a context in which we're parsing a statement.
   enum class ParsedStmtContext {
     /// This context permits declarations in language modes where declarations
     /// are not statements.
     AllowDeclarationsInC = 0x1,
     /// This context permits standalone OpenMP directives.
     AllowStandaloneOpenMPDirectives = 0x2,
     /// This context is at the top level of a GNU statement expression.
     InStmtExpr = 0x4,
 
     /// The context of a regular substatement.
     SubStmt = 0,
     /// The context of a compound-statement.
     Compound = AllowDeclarationsInC | AllowStandaloneOpenMPDirectives,
 
     LLVM_MARK_AS_BITMASK_ENUM(InStmtExpr)
   };
 
   /// Act on an expression statement that might be the last statement in a
   /// GNU statement expression. Checks whether we are actually at the end of
   /// a statement expression and builds a suitable expression statement.
   StmtResult handleExprStmt(ExprResult E, ParsedStmtContext StmtCtx);
 
 public:
   Parser(Preprocessor &PP, Sema &Actions, bool SkipFunctionBodies);
   ~Parser() override;
 
   const LangOptions &getLangOpts() const { return PP.getLangOpts(); }
   const TargetInfo &getTargetInfo() const { return PP.getTargetInfo(); }
   Preprocessor &getPreprocessor() const { return PP; }
   Sema &getActions() const { return Actions; }
   AttributeFactory &getAttrFactory() { return AttrFactory; }
 
   const Token &getCurToken() const { return Tok; }
   Scope *getCurScope() const { return Actions.getCurScope(); }
   void incrementMSManglingNumber() const {
     return Actions.incrementMSManglingNumber();
   }
 
   Decl  *getObjCDeclContext() const { return Actions.getObjCDeclContext(); }
 
   // Type forwarding.  All of these are statically 'void*', but they may all be
   // different actual classes based on the actions in place.
   typedef OpaquePtr<DeclGroupRef> DeclGroupPtrTy;
   typedef OpaquePtr<TemplateName> TemplateTy;
 
   typedef SmallVector<TemplateParameterList *, 4> TemplateParameterLists;
 
   typedef Sema::FullExprArg FullExprArg;
 
   // Parsing methods.
 
   /// Initialize - Warm up the parser.
   ///
   void Initialize();
 
   /// Parse the first top-level declaration in a translation unit.
   bool ParseFirstTopLevelDecl(DeclGroupPtrTy &Result);
 
   /// ParseTopLevelDecl - Parse one top-level declaration. Returns true if
   /// the EOF was encountered.
   bool ParseTopLevelDecl(DeclGroupPtrTy &Result, bool IsFirstDecl = false);
   bool ParseTopLevelDecl() {
     DeclGroupPtrTy Result;
     return ParseTopLevelDecl(Result);
   }
 
   /// ConsumeToken - Consume the current 'peek token' and lex the next one.
   /// This does not work with special tokens: string literals, code completion,
   /// annotation tokens and balanced tokens must be handled using the specific
   /// consume methods.
   /// Returns the location of the consumed token.
   SourceLocation ConsumeToken() {
     assert(!isTokenSpecial() &&
            "Should consume special tokens with Consume*Token");
     PrevTokLocation = Tok.getLocation();
     PP.Lex(Tok);
     return PrevTokLocation;
   }
 
   bool TryConsumeToken(tok::TokenKind Expected) {
     if (Tok.isNot(Expected))
       return false;
     assert(!isTokenSpecial() &&
            "Should consume special tokens with Consume*Token");
     PrevTokLocation = Tok.getLocation();
     PP.Lex(Tok);
     return true;
   }
 
   bool TryConsumeToken(tok::TokenKind Expected, SourceLocation &Loc) {
     if (!TryConsumeToken(Expected))
       return false;
     Loc = PrevTokLocation;
     return true;
   }
 
   /// ConsumeAnyToken - Dispatch to the right Consume* method based on the
   /// current token type.  This should only be used in cases where the type of
   /// the token really isn't known, e.g. in error recovery.
   SourceLocation ConsumeAnyToken(bool ConsumeCodeCompletionTok = false) {
     if (isTokenParen())
       return ConsumeParen();
     if (isTokenBracket())
       return ConsumeBracket();
     if (isTokenBrace())
       return ConsumeBrace();
     if (isTokenStringLiteral())
       return ConsumeStringToken();
     if (Tok.is(tok::code_completion))
       return ConsumeCodeCompletionTok ? ConsumeCodeCompletionToken()
                                       : handleUnexpectedCodeCompletionToken();
     if (Tok.isAnnotation())
       return ConsumeAnnotationToken();
     return ConsumeToken();
   }
 
 
   SourceLocation getEndOfPreviousToken() {
     return PP.getLocForEndOfToken(PrevTokLocation);
   }
 
   /// Retrieve the underscored keyword (_Nonnull, _Nullable) that corresponds
   /// to the given nullability kind.
   IdentifierInfo *getNullabilityKeyword(NullabilityKind nullability) {
     return Actions.getNullabilityKeyword(nullability);
   }
 
 private:
   //===--------------------------------------------------------------------===//
   // Low-Level token peeking and consumption methods.
   //
 
   /// isTokenParen - Return true if the cur token is '(' or ')'.
   bool isTokenParen() const {
     return Tok.isOneOf(tok::l_paren, tok::r_paren);
   }
   /// isTokenBracket - Return true if the cur token is '[' or ']'.
   bool isTokenBracket() const {
     return Tok.isOneOf(tok::l_square, tok::r_square);
   }
   /// isTokenBrace - Return true if the cur token is '{' or '}'.
   bool isTokenBrace() const {
     return Tok.isOneOf(tok::l_brace, tok::r_brace);
   }
   /// isTokenStringLiteral - True if this token is a string-literal.
   bool isTokenStringLiteral() const {
     return tok::isStringLiteral(Tok.getKind());
   }
   /// isTokenSpecial - True if this token requires special consumption methods.
   bool isTokenSpecial() const {
     return isTokenStringLiteral() || isTokenParen() || isTokenBracket() ||
            isTokenBrace() || Tok.is(tok::code_completion) || Tok.isAnnotation();
   }
 
   /// Returns true if the current token is '=' or is a type of '='.
   /// For typos, give a fixit to '='
   bool isTokenEqualOrEqualTypo();
 
   /// Return the current token to the token stream and make the given
   /// token the current token.
   void UnconsumeToken(Token &Consumed) {
       Token Next = Tok;
       PP.EnterToken(Consumed, /*IsReinject*/true);
       PP.Lex(Tok);
       PP.EnterToken(Next, /*IsReinject*/true);
   }
 
   SourceLocation ConsumeAnnotationToken() {
     assert(Tok.isAnnotation() && "wrong consume method");
     SourceLocation Loc = Tok.getLocation();
     PrevTokLocation = Tok.getAnnotationEndLoc();
     PP.Lex(Tok);
     return Loc;
   }
 
   /// ConsumeParen - This consume method keeps the paren count up-to-date.
   ///
   SourceLocation ConsumeParen() {
     assert(isTokenParen() && "wrong consume method");
     if (Tok.getKind() == tok::l_paren)
       ++ParenCount;
     else if (ParenCount) {
       AngleBrackets.clear(*this);
       --ParenCount;       // Don't let unbalanced )'s drive the count negative.
     }
     PrevTokLocation = Tok.getLocation();
     PP.Lex(Tok);
     return PrevTokLocation;
   }
 
   /// ConsumeBracket - This consume method keeps the bracket count up-to-date.
   ///
   SourceLocation ConsumeBracket() {
     assert(isTokenBracket() && "wrong consume method");
     if (Tok.getKind() == tok::l_square)
       ++BracketCount;
     else if (BracketCount) {
       AngleBrackets.clear(*this);
       --BracketCount;     // Don't let unbalanced ]'s drive the count negative.
     }
 
     PrevTokLocation = Tok.getLocation();
     PP.Lex(Tok);
     return PrevTokLocation;
   }
 
   /// ConsumeBrace - This consume method keeps the brace count up-to-date.
   ///
   SourceLocation ConsumeBrace() {
     assert(isTokenBrace() && "wrong consume method");
     if (Tok.getKind() == tok::l_brace)
       ++BraceCount;
     else if (BraceCount) {
       AngleBrackets.clear(*this);
       --BraceCount;     // Don't let unbalanced }'s drive the count negative.
     }
 
     PrevTokLocation = Tok.getLocation();
     PP.Lex(Tok);
     return PrevTokLocation;
   }
 
   /// ConsumeStringToken - Consume the current 'peek token', lexing a new one
   /// and returning the token kind.  This method is specific to strings, as it
   /// handles string literal concatenation, as per C99 5.1.1.2, translation
   /// phase #6.
   SourceLocation ConsumeStringToken() {
     assert(isTokenStringLiteral() &&
            "Should only consume string literals with this method");
     PrevTokLocation = Tok.getLocation();
     PP.Lex(Tok);
     return PrevTokLocation;
   }
 
   /// Consume the current code-completion token.
   ///
   /// This routine can be called to consume the code-completion token and
   /// continue processing in special cases where \c cutOffParsing() isn't
   /// desired, such as token caching or completion with lookahead.
   SourceLocation ConsumeCodeCompletionToken() {
     assert(Tok.is(tok::code_completion));
     PrevTokLocation = Tok.getLocation();
     PP.Lex(Tok);
     return PrevTokLocation;
   }
 
   ///\ brief When we are consuming a code-completion token without having
   /// matched specific position in the grammar, provide code-completion results
   /// based on context.
   ///
   /// \returns the source location of the code-completion token.
   SourceLocation handleUnexpectedCodeCompletionToken();
 
   /// Abruptly cut off parsing; mainly used when we have reached the
   /// code-completion point.
   void cutOffParsing() {
     if (PP.isCodeCompletionEnabled())
       PP.setCodeCompletionReached();
     // Cut off parsing by acting as if we reached the end-of-file.
     Tok.setKind(tok::eof);
   }
 
   /// Determine if we're at the end of the file or at a transition
   /// between modules.
   bool isEofOrEom() {
     tok::TokenKind Kind = Tok.getKind();
     return Kind == tok::eof || Kind == tok::annot_module_begin ||
            Kind == tok::annot_module_end || Kind == tok::annot_module_include;
   }
 
   /// Checks if the \p Level is valid for use in a fold expression.
   bool isFoldOperator(prec::Level Level) const;
 
   /// Checks if the \p Kind is a valid operator for fold expressions.
   bool isFoldOperator(tok::TokenKind Kind) const;
 
   /// Initialize all pragma handlers.
   void initializePragmaHandlers();
 
   /// Destroy and reset all pragma handlers.
   void resetPragmaHandlers();
 
   /// Handle the annotation token produced for #pragma unused(...)
   void HandlePragmaUnused();
 
   /// Handle the annotation token produced for
   /// #pragma GCC visibility...
   void HandlePragmaVisibility();
 
   /// Handle the annotation token produced for
   /// #pragma pack...
   void HandlePragmaPack();
 
   /// Handle the annotation token produced for
   /// #pragma ms_struct...
   void HandlePragmaMSStruct();
 
   /// Handle the annotation token produced for
   /// #pragma comment...
   void HandlePragmaMSComment();
 
   void HandlePragmaMSPointersToMembers();
 
   void HandlePragmaMSVtorDisp();
 
   void HandlePragmaMSPragma();
   bool HandlePragmaMSSection(StringRef PragmaName,
                              SourceLocation PragmaLocation);
   bool HandlePragmaMSSegment(StringRef PragmaName,
                              SourceLocation PragmaLocation);
   bool HandlePragmaMSInitSeg(StringRef PragmaName,
                              SourceLocation PragmaLocation);
 
   /// Handle the annotation token produced for
   /// #pragma align...
   void HandlePragmaAlign();
 
   /// Handle the annotation token produced for
   /// #pragma clang __debug dump...
   void HandlePragmaDump();
 
   /// Handle the annotation token produced for
   /// #pragma weak id...
   void HandlePragmaWeak();
 
   /// Handle the annotation token produced for
   /// #pragma weak id = id...
   void HandlePragmaWeakAlias();
 
   /// Handle the annotation token produced for
   /// #pragma redefine_extname...
   void HandlePragmaRedefineExtname();
 
   /// Handle the annotation token produced for
   /// #pragma STDC FP_CONTRACT...
   void HandlePragmaFPContract();
 
   /// Handle the annotation token produced for
   /// #pragma STDC FENV_ACCESS...
   void HandlePragmaFEnvAccess();
 
   /// \brief Handle the annotation token produced for
   /// #pragma clang fp ...
   void HandlePragmaFP();
 
   /// Handle the annotation token produced for
   /// #pragma OPENCL EXTENSION...
   void HandlePragmaOpenCLExtension();
 
   /// Handle the annotation token produced for
   /// #pragma clang __debug captured
   StmtResult HandlePragmaCaptured();
 
   /// Handle the annotation token produced for
   /// #pragma clang loop and #pragma unroll.
   bool HandlePragmaLoopHint(LoopHint &Hint);
 
   bool ParsePragmaAttributeSubjectMatchRuleSet(
       attr::ParsedSubjectMatchRuleSet &SubjectMatchRules,
       SourceLocation &AnyLoc, SourceLocation &LastMatchRuleEndLoc);
 
   void HandlePragmaAttribute();
 
   /// GetLookAheadToken - This peeks ahead N tokens and returns that token
   /// without consuming any tokens.  LookAhead(0) returns 'Tok', LookAhead(1)
   /// returns the token after Tok, etc.
   ///
   /// Note that this differs from the Preprocessor's LookAhead method, because
   /// the Parser always has one token lexed that the preprocessor doesn't.
   ///
   const Token &GetLookAheadToken(unsigned N) {
     if (N == 0 || Tok.is(tok::eof)) return Tok;
     return PP.LookAhead(N-1);
   }
 
 public:
   /// NextToken - This peeks ahead one token and returns it without
   /// consuming it.
   const Token &NextToken() {
     return PP.LookAhead(0);
   }
 
   /// getTypeAnnotation - Read a parsed type out of an annotation token.
   static ParsedType getTypeAnnotation(const Token &Tok) {
     return ParsedType::getFromOpaquePtr(Tok.getAnnotationValue());
   }
 
 private:
   static void setTypeAnnotation(Token &Tok, ParsedType T) {
     Tok.setAnnotationValue(T.getAsOpaquePtr());
   }
 
   static NamedDecl *getNonTypeAnnotation(const Token &Tok) {
     return static_cast<NamedDecl*>(Tok.getAnnotationValue());
   }
 
   static void setNonTypeAnnotation(Token &Tok, NamedDecl *ND) {
     Tok.setAnnotationValue(ND);
   }
 
   static IdentifierInfo *getIdentifierAnnotation(const Token &Tok) {
     return static_cast<IdentifierInfo*>(Tok.getAnnotationValue());
   }
 
   static void setIdentifierAnnotation(Token &Tok, IdentifierInfo *ND) {
     Tok.setAnnotationValue(ND);
   }
 
   /// Read an already-translated primary expression out of an annotation
   /// token.
   static ExprResult getExprAnnotation(const Token &Tok) {
     return ExprResult::getFromOpaquePointer(Tok.getAnnotationValue());
   }
 
   /// Set the primary expression corresponding to the given annotation
   /// token.
   static void setExprAnnotation(Token &Tok, ExprResult ER) {
     Tok.setAnnotationValue(ER.getAsOpaquePointer());
   }
 
 public:
   // If NeedType is true, then TryAnnotateTypeOrScopeToken will try harder to
   // find a type name by attempting typo correction.
   bool TryAnnotateTypeOrScopeToken();
   bool TryAnnotateTypeOrScopeTokenAfterScopeSpec(CXXScopeSpec &SS,
                                                  bool IsNewScope);
   bool TryAnnotateCXXScopeToken(bool EnteringContext = false);
 
   bool MightBeCXXScopeToken() {
     return Tok.is(tok::identifier) || Tok.is(tok::coloncolon) ||
            (Tok.is(tok::annot_template_id) &&
             NextToken().is(tok::coloncolon)) ||
            Tok.is(tok::kw_decltype) || Tok.is(tok::kw___super);
   }
   bool TryAnnotateOptionalCXXScopeToken(bool EnteringContext = false) {
     return MightBeCXXScopeToken() && TryAnnotateCXXScopeToken(EnteringContext);
   }
 
 private:
   enum AnnotatedNameKind {
     /// Annotation has failed and emitted an error.
     ANK_Error,
     /// The identifier is a tentatively-declared name.
     ANK_TentativeDecl,
     /// The identifier is a template name. FIXME: Add an annotation for that.
     ANK_TemplateName,
     /// The identifier can't be resolved.
     ANK_Unresolved,
     /// Annotation was successful.
     ANK_Success
   };
   AnnotatedNameKind TryAnnotateName(CorrectionCandidateCallback *CCC = nullptr);
 
   /// Push a tok::annot_cxxscope token onto the token stream.
   void AnnotateScopeToken(CXXScopeSpec &SS, bool IsNewAnnotation);
 
   /// TryAltiVecToken - Check for context-sensitive AltiVec identifier tokens,
   /// replacing them with the non-context-sensitive keywords.  This returns
   /// true if the token was replaced.
   bool TryAltiVecToken(DeclSpec &DS, SourceLocation Loc,
                        const char *&PrevSpec, unsigned &DiagID,
                        bool &isInvalid) {
     if (!getLangOpts().AltiVec && !getLangOpts().ZVector)
       return false;
 
     if (Tok.getIdentifierInfo() != Ident_vector &&
         Tok.getIdentifierInfo() != Ident_bool &&
         (!getLangOpts().AltiVec || Tok.getIdentifierInfo() != Ident_pixel))
       return false;
 
     return TryAltiVecTokenOutOfLine(DS, Loc, PrevSpec, DiagID, isInvalid);
   }
 
   /// TryAltiVecVectorToken - Check for context-sensitive AltiVec vector
   /// identifier token, replacing it with the non-context-sensitive __vector.
   /// This returns true if the token was replaced.
   bool TryAltiVecVectorToken() {
     if ((!getLangOpts().AltiVec && !getLangOpts().ZVector) ||
         Tok.getIdentifierInfo() != Ident_vector) return false;
     return TryAltiVecVectorTokenOutOfLine();
   }
 
   bool TryAltiVecVectorTokenOutOfLine();
   bool TryAltiVecTokenOutOfLine(DeclSpec &DS, SourceLocation Loc,
                                 const char *&PrevSpec, unsigned &DiagID,
                                 bool &isInvalid);
 
   /// Returns true if the current token is the identifier 'instancetype'.
   ///
   /// Should only be used in Objective-C language modes.
   bool isObjCInstancetype() {
     assert(getLangOpts().ObjC);
     if (Tok.isAnnotation())
       return false;
     if (!Ident_instancetype)
       Ident_instancetype = PP.getIdentifierInfo("instancetype");
     return Tok.getIdentifierInfo() == Ident_instancetype;
   }
 
   /// TryKeywordIdentFallback - For compatibility with system headers using
   /// keywords as identifiers, attempt to convert the current token to an
   /// identifier and optionally disable the keyword for the remainder of the
   /// translation unit. This returns false if the token was not replaced,
   /// otherwise emits a diagnostic and returns true.
   bool TryKeywordIdentFallback(bool DisableKeyword);
 
   /// Get the TemplateIdAnnotation from the token.
   TemplateIdAnnotation *takeTemplateIdAnnotation(const Token &tok);
 
   /// TentativeParsingAction - An object that is used as a kind of "tentative
   /// parsing transaction". It gets instantiated to mark the token position and
   /// after the token consumption is done, Commit() or Revert() is called to
   /// either "commit the consumed tokens" or revert to the previously marked
   /// token position. Example:
   ///
   ///   TentativeParsingAction TPA(*this);
   ///   ConsumeToken();
   ///   ....
   ///   TPA.Revert();
   ///
   class TentativeParsingAction {
     Parser &P;
     PreferredTypeBuilder PrevPreferredType;
     Token PrevTok;
     size_t PrevTentativelyDeclaredIdentifierCount;
     unsigned short PrevParenCount, PrevBracketCount, PrevBraceCount;
     bool isActive;
 
   public:
     explicit TentativeParsingAction(Parser& p) : P(p) {
       PrevPreferredType = P.PreferredType;
       PrevTok = P.Tok;
       PrevTentativelyDeclaredIdentifierCount =
           P.TentativelyDeclaredIdentifiers.size();
       PrevParenCount = P.ParenCount;
       PrevBracketCount = P.BracketCount;
       PrevBraceCount = P.BraceCount;
       P.PP.EnableBacktrackAtThisPos();
       isActive = true;
     }
     void Commit() {
       assert(isActive && "Parsing action was finished!");
       P.TentativelyDeclaredIdentifiers.resize(
           PrevTentativelyDeclaredIdentifierCount);
       P.PP.CommitBacktrackedTokens();
       isActive = false;
     }
     void Revert() {
       assert(isActive && "Parsing action was finished!");
       P.PP.Backtrack();
       P.PreferredType = PrevPreferredType;
       P.Tok = PrevTok;
       P.TentativelyDeclaredIdentifiers.resize(
           PrevTentativelyDeclaredIdentifierCount);
       P.ParenCount = PrevParenCount;
       P.BracketCount = PrevBracketCount;
       P.BraceCount = PrevBraceCount;
       isActive = false;
     }
     ~TentativeParsingAction() {
       assert(!isActive && "Forgot to call Commit or Revert!");
     }
   };
   /// A TentativeParsingAction that automatically reverts in its destructor.
   /// Useful for disambiguation parses that will always be reverted.
   class RevertingTentativeParsingAction
       : private Parser::TentativeParsingAction {
   public:
     RevertingTentativeParsingAction(Parser &P)
         : Parser::TentativeParsingAction(P) {}
     ~RevertingTentativeParsingAction() { Revert(); }
   };
 
   class UnannotatedTentativeParsingAction;
 
   /// ObjCDeclContextSwitch - An object used to switch context from
   /// an objective-c decl context to its enclosing decl context and
   /// back.
   class ObjCDeclContextSwitch {
     Parser &P;
     Decl *DC;
     SaveAndRestore<bool> WithinObjCContainer;
   public:
     explicit ObjCDeclContextSwitch(Parser &p)
       : P(p), DC(p.getObjCDeclContext()),
         WithinObjCContainer(P.ParsingInObjCContainer, DC != nullptr) {
       if (DC)
         P.Actions.ActOnObjCTemporaryExitContainerContext(cast<DeclContext>(DC));
     }
     ~ObjCDeclContextSwitch() {
       if (DC)
         P.Actions.ActOnObjCReenterContainerContext(cast<DeclContext>(DC));
     }
   };
 
   /// ExpectAndConsume - The parser expects that 'ExpectedTok' is next in the
   /// input.  If so, it is consumed and false is returned.
   ///
   /// If a trivial punctuator misspelling is encountered, a FixIt error
   /// diagnostic is issued and false is returned after recovery.
   ///
   /// If the input is malformed, this emits the specified diagnostic and true is
   /// returned.
   bool ExpectAndConsume(tok::TokenKind ExpectedTok,
                         unsigned Diag = diag::err_expected,
                         StringRef DiagMsg = "");
 
   /// The parser expects a semicolon and, if present, will consume it.
   ///
   /// If the next token is not a semicolon, this emits the specified diagnostic,
   /// or, if there's just some closing-delimiter noise (e.g., ')' or ']') prior
   /// to the semicolon, consumes that extra token.
   bool ExpectAndConsumeSemi(unsigned DiagID);
 
   /// The kind of extra semi diagnostic to emit.
   enum ExtraSemiKind {
     OutsideFunction = 0,
     InsideStruct = 1,
     InstanceVariableList = 2,
     AfterMemberFunctionDefinition = 3
   };
 
   /// Consume any extra semi-colons until the end of the line.
   void ConsumeExtraSemi(ExtraSemiKind Kind, DeclSpec::TST T = TST_unspecified);
 
   /// Return false if the next token is an identifier. An 'expected identifier'
   /// error is emitted otherwise.
   ///
   /// The parser tries to recover from the error by checking if the next token
   /// is a C++ keyword when parsing Objective-C++. Return false if the recovery
   /// was successful.
   bool expectIdentifier();
 
 public:
   //===--------------------------------------------------------------------===//
   // Scope manipulation
 
   /// ParseScope - Introduces a new scope for parsing. The kind of
   /// scope is determined by ScopeFlags. Objects of this type should
   /// be created on the stack to coincide with the position where the
   /// parser enters the new scope, and this object's constructor will
   /// create that new scope. Similarly, once the object is destroyed
   /// the parser will exit the scope.
   class ParseScope {
     Parser *Self;
     ParseScope(const ParseScope &) = delete;
     void operator=(const ParseScope &) = delete;
 
   public:
     // ParseScope - Construct a new object to manage a scope in the
     // parser Self where the new Scope is created with the flags
     // ScopeFlags, but only when we aren't about to enter a compound statement.
     ParseScope(Parser *Self, unsigned ScopeFlags, bool EnteredScope = true,
                bool BeforeCompoundStmt = false)
       : Self(Self) {
       if (EnteredScope && !BeforeCompoundStmt)
         Self->EnterScope(ScopeFlags);
       else {
         if (BeforeCompoundStmt)
           Self->incrementMSManglingNumber();
 
         this->Self = nullptr;
       }
     }
 
     // Exit - Exit the scope associated with this object now, rather
     // than waiting until the object is destroyed.
     void Exit() {
       if (Self) {
         Self->ExitScope();
         Self = nullptr;
       }
     }
 
     ~ParseScope() {
       Exit();
     }
   };
 
   /// EnterScope - Start a new scope.
   void EnterScope(unsigned ScopeFlags);
 
   /// ExitScope - Pop a scope off the scope stack.
   void ExitScope();
 
 private:
   /// RAII object used to modify the scope flags for the current scope.
   class ParseScopeFlags {
     Scope *CurScope;
     unsigned OldFlags;
     ParseScopeFlags(const ParseScopeFlags &) = delete;
     void operator=(const ParseScopeFlags &) = delete;
 
   public:
     ParseScopeFlags(Parser *Self, unsigned ScopeFlags, bool ManageFlags = true);
     ~ParseScopeFlags();
   };
 
   //===--------------------------------------------------------------------===//
   // Diagnostic Emission and Error recovery.
 
 public:
   DiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID);
   DiagnosticBuilder Diag(const Token &Tok, unsigned DiagID);
   DiagnosticBuilder Diag(unsigned DiagID) {
     return Diag(Tok, DiagID);
   }
 
 private:
   void SuggestParentheses(SourceLocation Loc, unsigned DK,
                           SourceRange ParenRange);
   void CheckNestedObjCContexts(SourceLocation AtLoc);
 
 public:
 
   /// Control flags for SkipUntil functions.
   enum SkipUntilFlags {
     StopAtSemi = 1 << 0,  ///< Stop skipping at semicolon
     /// Stop skipping at specified token, but don't skip the token itself
     StopBeforeMatch = 1 << 1,
     StopAtCodeCompletion = 1 << 2 ///< Stop at code completion
   };
 
   friend constexpr SkipUntilFlags operator|(SkipUntilFlags L,
                                             SkipUntilFlags R) {
     return static_cast<SkipUntilFlags>(static_cast<unsigned>(L) |
                                        static_cast<unsigned>(R));
   }
 
   /// SkipUntil - Read tokens until we get to the specified token, then consume
   /// it (unless StopBeforeMatch is specified).  Because we cannot guarantee
   /// that the token will ever occur, this skips to the next token, or to some
   /// likely good stopping point.  If Flags has StopAtSemi flag, skipping will
   /// stop at a ';' character. Balances (), [], and {} delimiter tokens while
   /// skipping.
   ///
   /// If SkipUntil finds the specified token, it returns true, otherwise it
   /// returns false.
   bool SkipUntil(tok::TokenKind T,
                  SkipUntilFlags Flags = static_cast<SkipUntilFlags>(0)) {
     return SkipUntil(llvm::makeArrayRef(T), Flags);
   }
   bool SkipUntil(tok::TokenKind T1, tok::TokenKind T2,
                  SkipUntilFlags Flags = static_cast<SkipUntilFlags>(0)) {
     tok::TokenKind TokArray[] = {T1, T2};
     return SkipUntil(TokArray, Flags);
   }
   bool SkipUntil(tok::TokenKind T1, tok::TokenKind T2, tok::TokenKind T3,
                  SkipUntilFlags Flags = static_cast<SkipUntilFlags>(0)) {
     tok::TokenKind TokArray[] = {T1, T2, T3};
     return SkipUntil(TokArray, Flags);
   }
   bool SkipUntil(ArrayRef<tok::TokenKind> Toks,
                  SkipUntilFlags Flags = static_cast<SkipUntilFlags>(0));
 
   /// SkipMalformedDecl - Read tokens until we get to some likely good stopping
   /// point for skipping past a simple-declaration.
   void SkipMalformedDecl();
 
   /// The location of the first statement inside an else that might
   /// have a missleading indentation. If there is no
   /// MisleadingIndentationChecker on an else active, this location is invalid.
   SourceLocation MisleadingIndentationElseLoc;
 
 private:
   //===--------------------------------------------------------------------===//
   // Lexing and parsing of C++ inline methods.
 
   struct ParsingClass;
 
   /// [class.mem]p1: "... the class is regarded as complete within
   /// - function bodies
   /// - default arguments
   /// - exception-specifications (TODO: C++0x)
   /// - and brace-or-equal-initializers for non-static data members
   /// (including such things in nested classes)."
   /// LateParsedDeclarations build the tree of those elements so they can
   /// be parsed after parsing the top-level class.
   class LateParsedDeclaration {
   public:
     virtual ~LateParsedDeclaration();
 
     virtual void ParseLexedMethodDeclarations();
     virtual void ParseLexedMemberInitializers();
     virtual void ParseLexedMethodDefs();
     virtual void ParseLexedAttributes();
     virtual void ParseLexedPragmas();
   };
 
   /// Inner node of the LateParsedDeclaration tree that parses
   /// all its members recursively.
   class LateParsedClass : public LateParsedDeclaration {
   public:
     LateParsedClass(Parser *P, ParsingClass *C);
     ~LateParsedClass() override;
 
     void ParseLexedMethodDeclarations() override;
     void ParseLexedMemberInitializers() override;
     void ParseLexedMethodDefs() override;
     void ParseLexedAttributes() override;
     void ParseLexedPragmas() override;
 
   private:
     Parser *Self;
     ParsingClass *Class;
   };
 
   /// Contains the lexed tokens of an attribute with arguments that
   /// may reference member variables and so need to be parsed at the
   /// end of the class declaration after parsing all other member
   /// member declarations.
   /// FIXME: Perhaps we should change the name of LateParsedDeclaration to
   /// LateParsedTokens.
   struct LateParsedAttribute : public LateParsedDeclaration {
     Parser *Self;
     CachedTokens Toks;
     IdentifierInfo &AttrName;
     IdentifierInfo *MacroII = nullptr;
     SourceLocation AttrNameLoc;
     SmallVector<Decl*, 2> Decls;
 
     explicit LateParsedAttribute(Parser *P, IdentifierInfo &Name,
                                  SourceLocation Loc)
       : Self(P), AttrName(Name), AttrNameLoc(Loc) {}
 
     void ParseLexedAttributes() override;
 
     void addDecl(Decl *D) { Decls.push_back(D); }
   };
 
   /// Contains the lexed tokens of a pragma with arguments that
   /// may reference member variables and so need to be parsed at the
   /// end of the class declaration after parsing all other member
   /// member declarations.
   class LateParsedPragma : public LateParsedDeclaration {
     Parser *Self = nullptr;
     AccessSpecifier AS = AS_none;
     CachedTokens Toks;
 
   public:
     explicit LateParsedPragma(Parser *P, AccessSpecifier AS)
         : Self(P), AS(AS) {}
 
     void takeToks(CachedTokens &Cached) { Toks.swap(Cached); }
     const CachedTokens &toks() const { return Toks; }
     AccessSpecifier getAccessSpecifier() const { return AS; }
 
     void ParseLexedPragmas() override;
   };
 
   // A list of late-parsed attributes.  Used by ParseGNUAttributes.
   class LateParsedAttrList: public SmallVector<LateParsedAttribute *, 2> {
   public:
     LateParsedAttrList(bool PSoon = false) : ParseSoon(PSoon) { }
 
     bool parseSoon() { return ParseSoon; }
 
   private:
     bool ParseSoon;  // Are we planning to parse these shortly after creation?
   };
 
   /// Contains the lexed tokens of a member function definition
   /// which needs to be parsed at the end of the class declaration
   /// after parsing all other member declarations.
   struct LexedMethod : public LateParsedDeclaration {
     Parser *Self;
     Decl *D;
     CachedTokens Toks;
 
     /// Whether this member function had an associated template
     /// scope. When true, D is a template declaration.
     /// otherwise, it is a member function declaration.
     bool TemplateScope;
 
     explicit LexedMethod(Parser* P, Decl *MD)
       : Self(P), D(MD), TemplateScope(false) {}
 
     void ParseLexedMethodDefs() override;
   };
 
   /// LateParsedDefaultArgument - Keeps track of a parameter that may
   /// have a default argument that cannot be parsed yet because it
   /// occurs within a member function declaration inside the class
   /// (C++ [class.mem]p2).
   struct LateParsedDefaultArgument {
     explicit LateParsedDefaultArgument(Decl *P,
                                        std::unique_ptr<CachedTokens> Toks = nullptr)
       : Param(P), Toks(std::move(Toks)) { }
 
     /// Param - The parameter declaration for this parameter.
     Decl *Param;
 
     /// Toks - The sequence of tokens that comprises the default
     /// argument expression, not including the '=' or the terminating
     /// ')' or ','. This will be NULL for parameters that have no
     /// default argument.
     std::unique_ptr<CachedTokens> Toks;
   };
 
   /// LateParsedMethodDeclaration - A method declaration inside a class that
   /// contains at least one entity whose parsing needs to be delayed
   /// until the class itself is completely-defined, such as a default
   /// argument (C++ [class.mem]p2).
   struct LateParsedMethodDeclaration : public LateParsedDeclaration {
     explicit LateParsedMethodDeclaration(Parser *P, Decl *M)
       : Self(P), Method(M), TemplateScope(false),
         ExceptionSpecTokens(nullptr) {}
 
     void ParseLexedMethodDeclarations() override;
 
     Parser* Self;
 
     /// Method - The method declaration.
     Decl *Method;
 
     /// Whether this member function had an associated template
     /// scope. When true, D is a template declaration.
     /// otherwise, it is a member function declaration.
     bool TemplateScope;
 
     /// DefaultArgs - Contains the parameters of the function and
     /// their default arguments. At least one of the parameters will
     /// have a default argument, but all of the parameters of the
     /// method will be stored so that they can be reintroduced into
     /// scope at the appropriate times.
     SmallVector<LateParsedDefaultArgument, 8> DefaultArgs;
 
     /// The set of tokens that make up an exception-specification that
     /// has not yet been parsed.
     CachedTokens *ExceptionSpecTokens;
   };
 
   /// LateParsedMemberInitializer - An initializer for a non-static class data
   /// member whose parsing must to be delayed until the class is completely
   /// defined (C++11 [class.mem]p2).
   struct LateParsedMemberInitializer : public LateParsedDeclaration {
     LateParsedMemberInitializer(Parser *P, Decl *FD)
       : Self(P), Field(FD) { }
 
     void ParseLexedMemberInitializers() override;
 
     Parser *Self;
 
     /// Field - The field declaration.
     Decl *Field;
 
     /// CachedTokens - The sequence of tokens that comprises the initializer,
     /// including any leading '='.
     CachedTokens Toks;
   };
 
   /// LateParsedDeclarationsContainer - During parsing of a top (non-nested)
   /// C++ class, its method declarations that contain parts that won't be
   /// parsed until after the definition is completed (C++ [class.mem]p2),
   /// the method declarations and possibly attached inline definitions
   /// will be stored here with the tokens that will be parsed to create those
   /// entities.
   typedef SmallVector<LateParsedDeclaration*,2> LateParsedDeclarationsContainer;
 
   /// Representation of a class that has been parsed, including
   /// any member function declarations or definitions that need to be
   /// parsed after the corresponding top-level class is complete.
   struct ParsingClass {
     ParsingClass(Decl *TagOrTemplate, bool TopLevelClass, bool IsInterface)
       : TopLevelClass(TopLevelClass), TemplateScope(false),
         IsInterface(IsInterface), TagOrTemplate(TagOrTemplate) { }
 
     /// Whether this is a "top-level" class, meaning that it is
     /// not nested within another class.
     bool TopLevelClass : 1;
 
     /// Whether this class had an associated template
     /// scope. When true, TagOrTemplate is a template declaration;
     /// otherwise, it is a tag declaration.
     bool TemplateScope : 1;
 
     /// Whether this class is an __interface.
     bool IsInterface : 1;
 
     /// The class or class template whose definition we are parsing.
     Decl *TagOrTemplate;
 
     /// LateParsedDeclarations - Method declarations, inline definitions and
     /// nested classes that contain pieces whose parsing will be delayed until
     /// the top-level class is fully defined.
     LateParsedDeclarationsContainer LateParsedDeclarations;
   };
 
   /// The stack of classes that is currently being
   /// parsed. Nested and local classes will be pushed onto this stack
   /// when they are parsed, and removed afterward.
   std::stack<ParsingClass *> ClassStack;
 
   ParsingClass &getCurrentClass() {
     assert(!ClassStack.empty() && "No lexed method stacks!");
     return *ClassStack.top();
   }
 
   /// RAII object used to manage the parsing of a class definition.
   class ParsingClassDefinition {
     Parser &P;
     bool Popped;
     Sema::ParsingClassState State;
 
   public:
     ParsingClassDefinition(Parser &P, Decl *TagOrTemplate, bool TopLevelClass,
                            bool IsInterface)
       : P(P), Popped(false),
         State(P.PushParsingClass(TagOrTemplate, TopLevelClass, IsInterface)) {
     }
 
     /// Pop this class of the stack.
     void Pop() {
       assert(!Popped && "Nested class has already been popped");
       Popped = true;
       P.PopParsingClass(State);
     }
 
     ~ParsingClassDefinition() {
       if (!Popped)
         P.PopParsingClass(State);
     }
   };
 
   /// Contains information about any template-specific
   /// information that has been parsed prior to parsing declaration
   /// specifiers.
   struct ParsedTemplateInfo {
     ParsedTemplateInfo()
       : Kind(NonTemplate), TemplateParams(nullptr), TemplateLoc() { }
 
     ParsedTemplateInfo(TemplateParameterLists *TemplateParams,
                        bool isSpecialization,
                        bool lastParameterListWasEmpty = false)
       : Kind(isSpecialization? ExplicitSpecialization : Template),
         TemplateParams(TemplateParams),
         LastParameterListWasEmpty(lastParameterListWasEmpty) { }
 
     explicit ParsedTemplateInfo(SourceLocation ExternLoc,
                                 SourceLocation TemplateLoc)
       : Kind(ExplicitInstantiation), TemplateParams(nullptr),
         ExternLoc(ExternLoc), TemplateLoc(TemplateLoc),
         LastParameterListWasEmpty(false){ }
 
     /// The kind of template we are parsing.
     enum {
       /// We are not parsing a template at all.
       NonTemplate = 0,
       /// We are parsing a template declaration.
       Template,
       /// We are parsing an explicit specialization.
       ExplicitSpecialization,
       /// We are parsing an explicit instantiation.
       ExplicitInstantiation
     } Kind;
 
     /// The template parameter lists, for template declarations
     /// and explicit specializations.
     TemplateParameterLists *TemplateParams;
 
     /// The location of the 'extern' keyword, if any, for an explicit
     /// instantiation
     SourceLocation ExternLoc;
 
     /// The location of the 'template' keyword, for an explicit
     /// instantiation.
     SourceLocation TemplateLoc;
 
     /// Whether the last template parameter list was empty.
     bool LastParameterListWasEmpty;
 
     SourceRange getSourceRange() const LLVM_READONLY;
   };
 
   void LexTemplateFunctionForLateParsing(CachedTokens &Toks);
   void ParseLateTemplatedFuncDef(LateParsedTemplate &LPT);
 
   static void LateTemplateParserCallback(void *P, LateParsedTemplate &LPT);
   static void LateTemplateParserCleanupCallback(void *P);
 
   Sema::ParsingClassState
   PushParsingClass(Decl *TagOrTemplate, bool TopLevelClass, bool IsInterface);
   void DeallocateParsedClasses(ParsingClass *Class);
   void PopParsingClass(Sema::ParsingClassState);
 
   enum CachedInitKind {
     CIK_DefaultArgument,
     CIK_DefaultInitializer
   };
 
   NamedDecl *ParseCXXInlineMethodDef(AccessSpecifier AS,
                                      ParsedAttributes &AccessAttrs,
                                      ParsingDeclarator &D,
                                      const ParsedTemplateInfo &TemplateInfo,
                                      const VirtSpecifiers &VS,
                                      SourceLocation PureSpecLoc);
   void ParseCXXNonStaticMemberInitializer(Decl *VarD);
   void ParseLexedAttributes(ParsingClass &Class);
   void ParseLexedAttributeList(LateParsedAttrList &LAs, Decl *D,
                                bool EnterScope, bool OnDefinition);
   void ParseLexedAttribute(LateParsedAttribute &LA,
                            bool EnterScope, bool OnDefinition);
   void ParseLexedMethodDeclarations(ParsingClass &Class);
   void ParseLexedMethodDeclaration(LateParsedMethodDeclaration &LM);
   void ParseLexedMethodDefs(ParsingClass &Class);
   void ParseLexedMethodDef(LexedMethod &LM);
   void ParseLexedMemberInitializers(ParsingClass &Class);
   void ParseLexedMemberInitializer(LateParsedMemberInitializer &MI);
   void ParseLexedObjCMethodDefs(LexedMethod &LM, bool parseMethod);
   void ParseLexedPragmas(ParsingClass &Class);
   void ParseLexedPragma(LateParsedPragma &LP);
   bool ConsumeAndStoreFunctionPrologue(CachedTokens &Toks);
   bool ConsumeAndStoreInitializer(CachedTokens &Toks, CachedInitKind CIK);
   bool ConsumeAndStoreConditional(CachedTokens &Toks);
   bool ConsumeAndStoreUntil(tok::TokenKind T1,
                             CachedTokens &Toks,
                             bool StopAtSemi = true,
                             bool ConsumeFinalToken = true) {
     return ConsumeAndStoreUntil(T1, T1, Toks, StopAtSemi, ConsumeFinalToken);
   }
   bool ConsumeAndStoreUntil(tok::TokenKind T1, tok::TokenKind T2,
                             CachedTokens &Toks,
                             bool StopAtSemi = true,
                             bool ConsumeFinalToken = true);
 
   //===--------------------------------------------------------------------===//
   // C99 6.9: External Definitions.
   struct ParsedAttributesWithRange : ParsedAttributes {
     ParsedAttributesWithRange(AttributeFactory &factory)
       : ParsedAttributes(factory) {}
 
     void clear() {
       ParsedAttributes::clear();
       Range = SourceRange();
     }
 
     SourceRange Range;
   };
   struct ParsedAttributesViewWithRange : ParsedAttributesView {
     ParsedAttributesViewWithRange() : ParsedAttributesView() {}
     void clearListOnly() {
       ParsedAttributesView::clearListOnly();
       Range = SourceRange();
     }
 
     SourceRange Range;
   };
 
   DeclGroupPtrTy ParseExternalDeclaration(ParsedAttributesWithRange &attrs,
                                           ParsingDeclSpec *DS = nullptr);
   bool isDeclarationAfterDeclarator();
   bool isStartOfFunctionDefinition(const ParsingDeclarator &Declarator);
   DeclGroupPtrTy ParseDeclarationOrFunctionDefinition(
                                                   ParsedAttributesWithRange &attrs,
                                                   ParsingDeclSpec *DS = nullptr,
                                                   AccessSpecifier AS = AS_none);
   DeclGroupPtrTy ParseDeclOrFunctionDefInternal(ParsedAttributesWithRange &attrs,
                                                 ParsingDeclSpec &DS,
                                                 AccessSpecifier AS);
 
   void SkipFunctionBody();
   Decl *ParseFunctionDefinition(ParsingDeclarator &D,
                  const ParsedTemplateInfo &TemplateInfo = ParsedTemplateInfo(),
                  LateParsedAttrList *LateParsedAttrs = nullptr);
   void ParseKNRParamDeclarations(Declarator &D);
   // EndLoc is filled with the location of the last token of the simple-asm.
   ExprResult ParseSimpleAsm(bool ForAsmLabel, SourceLocation *EndLoc);
   ExprResult ParseAsmStringLiteral(bool ForAsmLabel);
 
   // Objective-C External Declarations
   void MaybeSkipAttributes(tok::ObjCKeywordKind Kind);
   DeclGroupPtrTy ParseObjCAtDirectives(ParsedAttributesWithRange &Attrs);
   DeclGroupPtrTy ParseObjCAtClassDeclaration(SourceLocation atLoc);
   Decl *ParseObjCAtInterfaceDeclaration(SourceLocation AtLoc,
                                         ParsedAttributes &prefixAttrs);
   class ObjCTypeParamListScope;
   ObjCTypeParamList *parseObjCTypeParamList();
   ObjCTypeParamList *parseObjCTypeParamListOrProtocolRefs(
       ObjCTypeParamListScope &Scope, SourceLocation &lAngleLoc,
       SmallVectorImpl<IdentifierLocPair> &protocolIdents,
       SourceLocation &rAngleLoc, bool mayBeProtocolList = true);
 
   void HelperActionsForIvarDeclarations(Decl *interfaceDecl, SourceLocation atLoc,
                                         BalancedDelimiterTracker &T,
                                         SmallVectorImpl<Decl *> &AllIvarDecls,
                                         bool RBraceMissing);
   void ParseObjCClassInstanceVariables(Decl *interfaceDecl,
                                        tok::ObjCKeywordKind visibility,
                                        SourceLocation atLoc);
   bool ParseObjCProtocolReferences(SmallVectorImpl<Decl *> &P,
                                    SmallVectorImpl<SourceLocation> &PLocs,
                                    bool WarnOnDeclarations,
                                    bool ForObjCContainer,
                                    SourceLocation &LAngleLoc,
                                    SourceLocation &EndProtoLoc,
                                    bool consumeLastToken);
 
   /// Parse the first angle-bracket-delimited clause for an
   /// Objective-C object or object pointer type, which may be either
   /// type arguments or protocol qualifiers.
   void parseObjCTypeArgsOrProtocolQualifiers(
          ParsedType baseType,
          SourceLocation &typeArgsLAngleLoc,
          SmallVectorImpl<ParsedType> &typeArgs,
          SourceLocation &typeArgsRAngleLoc,
          SourceLocation &protocolLAngleLoc,
          SmallVectorImpl<Decl *> &protocols,
          SmallVectorImpl<SourceLocation> &protocolLocs,
          SourceLocation &protocolRAngleLoc,
          bool consumeLastToken,
          bool warnOnIncompleteProtocols);
 
   /// Parse either Objective-C type arguments or protocol qualifiers; if the
   /// former, also parse protocol qualifiers afterward.
   void parseObjCTypeArgsAndProtocolQualifiers(
          ParsedType baseType,
          SourceLocation &typeArgsLAngleLoc,
          SmallVectorImpl<ParsedType> &typeArgs,
          SourceLocation &typeArgsRAngleLoc,
          SourceLocation &protocolLAngleLoc,
          SmallVectorImpl<Decl *> &protocols,
          SmallVectorImpl<SourceLocation> &protocolLocs,
          SourceLocation &protocolRAngleLoc,
          bool consumeLastToken);
 
   /// Parse a protocol qualifier type such as '<NSCopying>', which is
   /// an anachronistic way of writing 'id<NSCopying>'.
   TypeResult parseObjCProtocolQualifierType(SourceLocation &rAngleLoc);
 
   /// Parse Objective-C type arguments and protocol qualifiers, extending the
   /// current type with the parsed result.
   TypeResult parseObjCTypeArgsAndProtocolQualifiers(SourceLocation loc,
                                                     ParsedType type,
                                                     bool consumeLastToken,
                                                     SourceLocation &endLoc);
 
   void ParseObjCInterfaceDeclList(tok::ObjCKeywordKind contextKey,
                                   Decl *CDecl);
   DeclGroupPtrTy ParseObjCAtProtocolDeclaration(SourceLocation atLoc,
                                                 ParsedAttributes &prefixAttrs);
 
   struct ObjCImplParsingDataRAII {
     Parser &P;
     Decl *Dcl;
     bool HasCFunction;
     typedef SmallVector<LexedMethod*, 8> LateParsedObjCMethodContainer;
     LateParsedObjCMethodContainer LateParsedObjCMethods;
 
     ObjCImplParsingDataRAII(Parser &parser, Decl *D)
       : P(parser), Dcl(D), HasCFunction(false) {
       P.CurParsedObjCImpl = this;
       Finished = false;
     }
     ~ObjCImplParsingDataRAII();
 
     void finish(SourceRange AtEnd);
     bool isFinished() const { return Finished; }
 
   private:
     bool Finished;
   };
   ObjCImplParsingDataRAII *CurParsedObjCImpl;
   void StashAwayMethodOrFunctionBodyTokens(Decl *MDecl);
 
   DeclGroupPtrTy ParseObjCAtImplementationDeclaration(SourceLocation AtLoc,
                                                       ParsedAttributes &Attrs);
   DeclGroupPtrTy ParseObjCAtEndDeclaration(SourceRange atEnd);
   Decl *ParseObjCAtAliasDeclaration(SourceLocation atLoc);
   Decl *ParseObjCPropertySynthesize(SourceLocation atLoc);
   Decl *ParseObjCPropertyDynamic(SourceLocation atLoc);
 
   IdentifierInfo *ParseObjCSelectorPiece(SourceLocation &MethodLocation);
   // Definitions for Objective-c context sensitive keywords recognition.
   enum ObjCTypeQual {
     objc_in=0, objc_out, objc_inout, objc_oneway, objc_bycopy, objc_byref,
     objc_nonnull, objc_nullable, objc_null_unspecified,
     objc_NumQuals
   };
   IdentifierInfo *ObjCTypeQuals[objc_NumQuals];
 
   bool isTokIdentifier_in() const;
 
   ParsedType ParseObjCTypeName(ObjCDeclSpec &DS, DeclaratorContext Ctx,
                                ParsedAttributes *ParamAttrs);
   void ParseObjCMethodRequirement();
   Decl *ParseObjCMethodPrototype(
             tok::ObjCKeywordKind MethodImplKind = tok::objc_not_keyword,
             bool MethodDefinition = true);
   Decl *ParseObjCMethodDecl(SourceLocation mLoc, tok::TokenKind mType,
             tok::ObjCKeywordKind MethodImplKind = tok::objc_not_keyword,
             bool MethodDefinition=true);
   void ParseObjCPropertyAttribute(ObjCDeclSpec &DS);
 
   Decl *ParseObjCMethodDefinition();
 
 public:
   //===--------------------------------------------------------------------===//
   // C99 6.5: Expressions.
 
   /// TypeCastState - State whether an expression is or may be a type cast.
   enum TypeCastState {
     NotTypeCast = 0,
     MaybeTypeCast,
     IsTypeCast
   };
 
   ExprResult ParseExpression(TypeCastState isTypeCast = NotTypeCast);
   ExprResult ParseConstantExpressionInExprEvalContext(
       TypeCastState isTypeCast = NotTypeCast);
   ExprResult ParseConstantExpression(TypeCastState isTypeCast = NotTypeCast);
   ExprResult ParseCaseExpression(SourceLocation CaseLoc);
   ExprResult ParseConstraintExpression();
   ExprResult
   ParseConstraintLogicalAndExpression(bool IsTrailingRequiresClause);
   ExprResult ParseConstraintLogicalOrExpression(bool IsTrailingRequiresClause);
   // Expr that doesn't include commas.
   ExprResult ParseAssignmentExpression(TypeCastState isTypeCast = NotTypeCast);
 
   ExprResult ParseMSAsmIdentifier(llvm::SmallVectorImpl<Token> &LineToks,
                                   unsigned &NumLineToksConsumed,
                                   bool IsUnevaluated);
 
   ExprResult ParseStringLiteralExpression(bool AllowUserDefinedLiteral = false);
 
 private:
   ExprResult ParseExpressionWithLeadingAt(SourceLocation AtLoc);
 
   ExprResult ParseExpressionWithLeadingExtension(SourceLocation ExtLoc);
 
   ExprResult ParseRHSOfBinaryExpression(ExprResult LHS,
                                         prec::Level MinPrec);
   /// Control what ParseCastExpression will parse.
   enum CastParseKind {
     AnyCastExpr = 0,
     UnaryExprOnly,
     PrimaryExprOnly
   };
   ExprResult ParseCastExpression(CastParseKind ParseKind,
                                  bool isAddressOfOperand,
                                  bool &NotCastExpr,
                                  TypeCastState isTypeCast,
                                  bool isVectorLiteral = false,
                                  bool *NotPrimaryExpression = nullptr);
   ExprResult ParseCastExpression(CastParseKind ParseKind,
                                  bool isAddressOfOperand = false,
                                  TypeCastState isTypeCast = NotTypeCast,
                                  bool isVectorLiteral = false,
                                  bool *NotPrimaryExpression = nullptr);
 
   /// Returns true if the next token cannot start an expression.
   bool isNotExpressionStart();
 
   /// Returns true if the next token would start a postfix-expression
   /// suffix.
   bool isPostfixExpressionSuffixStart() {
     tok::TokenKind K = Tok.getKind();
     return (K == tok::l_square || K == tok::l_paren ||
             K == tok::period || K == tok::arrow ||
             K == tok::plusplus || K == tok::minusminus);
   }
 
   bool diagnoseUnknownTemplateId(ExprResult TemplateName, SourceLocation Less);
   void checkPotentialAngleBracket(ExprResult &PotentialTemplateName);
   bool checkPotentialAngleBracketDelimiter(const AngleBracketTracker::Loc &,
                                            const Token &OpToken);
   bool checkPotentialAngleBracketDelimiter(const Token &OpToken) {
     if (auto *Info = AngleBrackets.getCurrent(*this))
       return checkPotentialAngleBracketDelimiter(*Info, OpToken);
     return false;
   }
 
   ExprResult ParsePostfixExpressionSuffix(ExprResult LHS);
   ExprResult ParseUnaryExprOrTypeTraitExpression();
   ExprResult ParseBuiltinPrimaryExpression();
 
   ExprResult ParseExprAfterUnaryExprOrTypeTrait(const Token &OpTok,
                                                      bool &isCastExpr,
                                                      ParsedType &CastTy,
                                                      SourceRange &CastRange);
 
   typedef SmallVector<Expr*, 20> ExprListTy;
   typedef SmallVector<SourceLocation, 20> CommaLocsTy;
 
   /// ParseExpressionList - Used for C/C++ (argument-)expression-list.
   bool ParseExpressionList(SmallVectorImpl<Expr *> &Exprs,
                            SmallVectorImpl<SourceLocation> &CommaLocs,
                            llvm::function_ref<void()> ExpressionStarts =
                                llvm::function_ref<void()>());
 
   /// ParseSimpleExpressionList - A simple comma-separated list of expressions,
   /// used for misc language extensions.
   bool ParseSimpleExpressionList(SmallVectorImpl<Expr*> &Exprs,
                                  SmallVectorImpl<SourceLocation> &CommaLocs);
 
 
   /// ParenParseOption - Control what ParseParenExpression will parse.
   enum ParenParseOption {
     SimpleExpr,      // Only parse '(' expression ')'
     FoldExpr,        // Also allow fold-expression <anything>
     CompoundStmt,    // Also allow '(' compound-statement ')'
     CompoundLiteral, // Also allow '(' type-name ')' '{' ... '}'
     CastExpr         // Also allow '(' type-name ')' <anything>
   };
   ExprResult ParseParenExpression(ParenParseOption &ExprType,
                                         bool stopIfCastExpr,
                                         bool isTypeCast,
                                         ParsedType &CastTy,
                                         SourceLocation &RParenLoc);
 
   ExprResult ParseCXXAmbiguousParenExpression(
       ParenParseOption &ExprType, ParsedType &CastTy,
       BalancedDelimiterTracker &Tracker, ColonProtectionRAIIObject &ColonProt);
   ExprResult ParseCompoundLiteralExpression(ParsedType Ty,
                                                   SourceLocation LParenLoc,
                                                   SourceLocation RParenLoc);
 
   ExprResult ParseGenericSelectionExpression();
 
   ExprResult ParseObjCBoolLiteral();
 
   ExprResult ParseFoldExpression(ExprResult LHS, BalancedDelimiterTracker &T);
 
   //===--------------------------------------------------------------------===//
   // C++ Expressions
   ExprResult tryParseCXXIdExpression(CXXScopeSpec &SS, bool isAddressOfOperand,
                                      Token &Replacement);
   ExprResult ParseCXXIdExpression(bool isAddressOfOperand = false);
 
   bool areTokensAdjacent(const Token &A, const Token &B);
 
   void CheckForTemplateAndDigraph(Token &Next, ParsedType ObjectTypePtr,
                                   bool EnteringContext, IdentifierInfo &II,
                                   CXXScopeSpec &SS);
 
   bool ParseOptionalCXXScopeSpecifier(CXXScopeSpec &SS, ParsedType ObjectType,
                                       bool EnteringContext,
                                       bool *MayBePseudoDestructor = nullptr,
                                       bool IsTypename = false,
                                       IdentifierInfo **LastII = nullptr,
                                       bool OnlyNamespace = false,
                                       bool InUsingDeclaration = false);
 
   //===--------------------------------------------------------------------===//
   // C++11 5.1.2: Lambda expressions
 
   /// Result of tentatively parsing a lambda-introducer.
   enum class LambdaIntroducerTentativeParse {
     /// This appears to be a lambda-introducer, which has been fully parsed.
     Success,
     /// This is a lambda-introducer, but has not been fully parsed, and this
     /// function needs to be called again to parse it.
     Incomplete,
     /// This is definitely an Objective-C message send expression, rather than
     /// a lambda-introducer, attribute-specifier, or array designator.
     MessageSend,
     /// This is not a lambda-introducer.
     Invalid,
   };
 
   // [...] () -> type {...}
   ExprResult ParseLambdaExpression();
   ExprResult TryParseLambdaExpression();
   bool
   ParseLambdaIntroducer(LambdaIntroducer &Intro,
                         LambdaIntroducerTentativeParse *Tentative = nullptr);
   ExprResult ParseLambdaExpressionAfterIntroducer(LambdaIntroducer &Intro);
 
   //===--------------------------------------------------------------------===//
   // C++ 5.2p1: C++ Casts
   ExprResult ParseCXXCasts();
 
   /// Parse a __builtin_bit_cast(T, E), used to implement C++2a std::bit_cast.
   ExprResult ParseBuiltinBitCast();
 
   //===--------------------------------------------------------------------===//
   // C++ 5.2p1: C++ Type Identification
   ExprResult ParseCXXTypeid();
 
   //===--------------------------------------------------------------------===//
   //  C++ : Microsoft __uuidof Expression
   ExprResult ParseCXXUuidof();
 
   //===--------------------------------------------------------------------===//
   // C++ 5.2.4: C++ Pseudo-Destructor Expressions
   ExprResult ParseCXXPseudoDestructor(Expr *Base, SourceLocation OpLoc,
                                             tok::TokenKind OpKind,
                                             CXXScopeSpec &SS,
                                             ParsedType ObjectType);
 
   //===--------------------------------------------------------------------===//
   // C++ 9.3.2: C++ 'this' pointer
   ExprResult ParseCXXThis();
 
   //===--------------------------------------------------------------------===//
   // C++ 15: C++ Throw Expression
   ExprResult ParseThrowExpression();
 
   ExceptionSpecificationType tryParseExceptionSpecification(
                     bool Delayed,
                     SourceRange &SpecificationRange,
                     SmallVectorImpl<ParsedType> &DynamicExceptions,
                     SmallVectorImpl<SourceRange> &DynamicExceptionRanges,
                     ExprResult &NoexceptExpr,
                     CachedTokens *&ExceptionSpecTokens);
 
   // EndLoc is filled with the location of the last token of the specification.
   ExceptionSpecificationType ParseDynamicExceptionSpecification(
                                   SourceRange &SpecificationRange,
                                   SmallVectorImpl<ParsedType> &Exceptions,
                                   SmallVectorImpl<SourceRange> &Ranges);
 
   //===--------------------------------------------------------------------===//
   // C++0x 8: Function declaration trailing-return-type
   TypeResult ParseTrailingReturnType(SourceRange &Range,
                                      bool MayBeFollowedByDirectInit);
 
   //===--------------------------------------------------------------------===//
   // C++ 2.13.5: C++ Boolean Literals
   ExprResult ParseCXXBoolLiteral();
 
   //===--------------------------------------------------------------------===//
   // C++ 5.2.3: Explicit type conversion (functional notation)
   ExprResult ParseCXXTypeConstructExpression(const DeclSpec &DS);
 
   /// ParseCXXSimpleTypeSpecifier - [C++ 7.1.5.2] Simple type specifiers.
   /// This should only be called when the current token is known to be part of
   /// simple-type-specifier.
   void ParseCXXSimpleTypeSpecifier(DeclSpec &DS);
 
   bool ParseCXXTypeSpecifierSeq(DeclSpec &DS);
 
   //===--------------------------------------------------------------------===//
   // C++ 5.3.4 and 5.3.5: C++ new and delete
   bool ParseExpressionListOrTypeId(SmallVectorImpl<Expr*> &Exprs,
                                    Declarator &D);
   void ParseDirectNewDeclarator(Declarator &D);
   ExprResult ParseCXXNewExpression(bool UseGlobal, SourceLocation Start);
   ExprResult ParseCXXDeleteExpression(bool UseGlobal,
                                             SourceLocation Start);
 
   //===--------------------------------------------------------------------===//
   // C++ if/switch/while/for condition expression.
   struct ForRangeInfo;
   Sema::ConditionResult ParseCXXCondition(StmtResult *InitStmt,
                                           SourceLocation Loc,
                                           Sema::ConditionKind CK,
                                           ForRangeInfo *FRI = nullptr);
 
   //===--------------------------------------------------------------------===//
   // C++ Coroutines
 
   ExprResult ParseCoyieldExpression();
 
   //===--------------------------------------------------------------------===//
   // C++ Concepts
 
   ExprResult ParseRequiresExpression();
   void ParseTrailingRequiresClause(Declarator &D);
 
   //===--------------------------------------------------------------------===//
   // C99 6.7.8: Initialization.
 
   /// ParseInitializer
   ///       initializer: [C99 6.7.8]
   ///         assignment-expression
   ///         '{' ...
   ExprResult ParseInitializer() {
     if (Tok.isNot(tok::l_brace))
       return ParseAssignmentExpression();
     return ParseBraceInitializer();
   }
   bool MayBeDesignationStart();
   ExprResult ParseBraceInitializer();
   ExprResult ParseInitializerWithPotentialDesignator(
       llvm::function_ref<void(const Designation &)> CodeCompleteCB);
 
   //===--------------------------------------------------------------------===//
   // clang Expressions
 
   ExprResult ParseBlockLiteralExpression();  // ^{...}
 
   //===--------------------------------------------------------------------===//
   // Objective-C Expressions
   ExprResult ParseObjCAtExpression(SourceLocation AtLocation);
   ExprResult ParseObjCStringLiteral(SourceLocation AtLoc);
   ExprResult ParseObjCCharacterLiteral(SourceLocation AtLoc);
   ExprResult ParseObjCNumericLiteral(SourceLocation AtLoc);
   ExprResult ParseObjCBooleanLiteral(SourceLocation AtLoc, bool ArgValue);
   ExprResult ParseObjCArrayLiteral(SourceLocation AtLoc);
   ExprResult ParseObjCDictionaryLiteral(SourceLocation AtLoc);
   ExprResult ParseObjCBoxedExpr(SourceLocation AtLoc);
   ExprResult ParseObjCEncodeExpression(SourceLocation AtLoc);
   ExprResult ParseObjCSelectorExpression(SourceLocation AtLoc);
   ExprResult ParseObjCProtocolExpression(SourceLocation AtLoc);
   bool isSimpleObjCMessageExpression();
   ExprResult ParseObjCMessageExpression();
   ExprResult ParseObjCMessageExpressionBody(SourceLocation LBracloc,
                                             SourceLocation SuperLoc,
                                             ParsedType ReceiverType,
                                             Expr *ReceiverExpr);
   ExprResult ParseAssignmentExprWithObjCMessageExprStart(
       SourceLocation LBracloc, SourceLocation SuperLoc,
       ParsedType ReceiverType, Expr *ReceiverExpr);
   bool ParseObjCXXMessageReceiver(bool &IsExpr, void *&TypeOrExpr);
 
   //===--------------------------------------------------------------------===//
   // C99 6.8: Statements and Blocks.
 
   /// A SmallVector of statements, with stack size 32 (as that is the only one
   /// used.)
   typedef SmallVector<Stmt*, 32> StmtVector;
   /// A SmallVector of expressions, with stack size 12 (the maximum used.)
   typedef SmallVector<Expr*, 12> ExprVector;
   /// A SmallVector of types.
   typedef SmallVector<ParsedType, 12> TypeVector;
 
   StmtResult
   ParseStatement(SourceLocation *TrailingElseLoc = nullptr,
                  ParsedStmtContext StmtCtx = ParsedStmtContext::SubStmt);
   StmtResult ParseStatementOrDeclaration(
       StmtVector &Stmts, ParsedStmtContext StmtCtx,
       SourceLocation *TrailingElseLoc = nullptr);
   StmtResult ParseStatementOrDeclarationAfterAttributes(
                                          StmtVector &Stmts,
                                          ParsedStmtContext StmtCtx,
                                          SourceLocation *TrailingElseLoc,
                                          ParsedAttributesWithRange &Attrs);
   StmtResult ParseExprStatement(ParsedStmtContext StmtCtx);
   StmtResult ParseLabeledStatement(ParsedAttributesWithRange &attrs,
                                    ParsedStmtContext StmtCtx);
   StmtResult ParseCaseStatement(ParsedStmtContext StmtCtx,
                                 bool MissingCase = false,
                                 ExprResult Expr = ExprResult());
   StmtResult ParseDefaultStatement(ParsedStmtContext StmtCtx);
   StmtResult ParseCompoundStatement(bool isStmtExpr = false);
   StmtResult ParseCompoundStatement(bool isStmtExpr,
                                     unsigned ScopeFlags);
   void ParseCompoundStatementLeadingPragmas();
   bool ConsumeNullStmt(StmtVector &Stmts);
   StmtResult ParseCompoundStatementBody(bool isStmtExpr = false);
   bool ParseParenExprOrCondition(StmtResult *InitStmt,
                                  Sema::ConditionResult &CondResult,
                                  SourceLocation Loc,
                                  Sema::ConditionKind CK);
   StmtResult ParseIfStatement(SourceLocation *TrailingElseLoc);
   StmtResult ParseSwitchStatement(SourceLocation *TrailingElseLoc);
   StmtResult ParseWhileStatement(SourceLocation *TrailingElseLoc);
   StmtResult ParseDoStatement();
   StmtResult ParseForStatement(SourceLocation *TrailingElseLoc);
   StmtResult ParseGotoStatement();
   StmtResult ParseContinueStatement();
   StmtResult ParseBreakStatement();
   StmtResult ParseReturnStatement();
   StmtResult ParseAsmStatement(bool &msAsm);
   StmtResult ParseMicrosoftAsmStatement(SourceLocation AsmLoc);
   StmtResult ParsePragmaLoopHint(StmtVector &Stmts,
                                  ParsedStmtContext StmtCtx,
                                  SourceLocation *TrailingElseLoc,
                                  ParsedAttributesWithRange &Attrs);
 
   /// Describes the behavior that should be taken for an __if_exists
   /// block.
   enum IfExistsBehavior {
     /// Parse the block; this code is always used.
     IEB_Parse,
     /// Skip the block entirely; this code is never used.
     IEB_Skip,
     /// Parse the block as a dependent block, which may be used in
     /// some template instantiations but not others.
     IEB_Dependent
   };
 
   /// Describes the condition of a Microsoft __if_exists or
   /// __if_not_exists block.
   struct IfExistsCondition {
     /// The location of the initial keyword.
     SourceLocation KeywordLoc;
     /// Whether this is an __if_exists block (rather than an
     /// __if_not_exists block).
     bool IsIfExists;
 
     /// Nested-name-specifier preceding the name.
     CXXScopeSpec SS;
 
     /// The name we're looking for.
     UnqualifiedId Name;
 
     /// The behavior of this __if_exists or __if_not_exists block
     /// should.
     IfExistsBehavior Behavior;
   };
 
   bool ParseMicrosoftIfExistsCondition(IfExistsCondition& Result);
   void ParseMicrosoftIfExistsStatement(StmtVector &Stmts);
   void ParseMicrosoftIfExistsExternalDeclaration();
   void ParseMicrosoftIfExistsClassDeclaration(DeclSpec::TST TagType,
                                               ParsedAttributes &AccessAttrs,
                                               AccessSpecifier &CurAS);
   bool ParseMicrosoftIfExistsBraceInitializer(ExprVector &InitExprs,
                                               bool &InitExprsOk);
   bool ParseAsmOperandsOpt(SmallVectorImpl<IdentifierInfo *> &Names,
                            SmallVectorImpl<Expr *> &Constraints,
                            SmallVectorImpl<Expr *> &Exprs);
 
   //===--------------------------------------------------------------------===//
   // C++ 6: Statements and Blocks
 
   StmtResult ParseCXXTryBlock();
   StmtResult ParseCXXTryBlockCommon(SourceLocation TryLoc, bool FnTry = false);
   StmtResult ParseCXXCatchBlock(bool FnCatch = false);
 
   //===--------------------------------------------------------------------===//
   // MS: SEH Statements and Blocks
 
   StmtResult ParseSEHTryBlock();
   StmtResult ParseSEHExceptBlock(SourceLocation Loc);
   StmtResult ParseSEHFinallyBlock(SourceLocation Loc);
   StmtResult ParseSEHLeaveStatement();
 
   //===--------------------------------------------------------------------===//
   // Objective-C Statements
 
   StmtResult ParseObjCAtStatement(SourceLocation atLoc,
                                   ParsedStmtContext StmtCtx);
   StmtResult ParseObjCTryStmt(SourceLocation atLoc);
   StmtResult ParseObjCThrowStmt(SourceLocation atLoc);
   StmtResult ParseObjCSynchronizedStmt(SourceLocation atLoc);
   StmtResult ParseObjCAutoreleasePoolStmt(SourceLocation atLoc);
 
 
   //===--------------------------------------------------------------------===//
   // C99 6.7: Declarations.
 
   /// A context for parsing declaration specifiers.  TODO: flesh this
   /// out, there are other significant restrictions on specifiers than
   /// would be best implemented in the parser.
   enum class DeclSpecContext {
     DSC_normal, // normal context
     DSC_class,  // class context, enables 'friend'
     DSC_type_specifier, // C++ type-specifier-seq or C specifier-qualifier-list
     DSC_trailing, // C++11 trailing-type-specifier in a trailing return type
     DSC_alias_declaration, // C++11 type-specifier-seq in an alias-declaration
     DSC_top_level, // top-level/namespace declaration context
     DSC_template_param, // template parameter context
     DSC_template_type_arg, // template type argument context
     DSC_objc_method_result, // ObjC method result context, enables 'instancetype'
     DSC_condition // condition declaration context
   };
 
   /// Is this a context in which we are parsing just a type-specifier (or
   /// trailing-type-specifier)?
   static bool isTypeSpecifier(DeclSpecContext DSC) {
     switch (DSC) {
     case DeclSpecContext::DSC_normal:
     case DeclSpecContext::DSC_template_param:
     case DeclSpecContext::DSC_class:
     case DeclSpecContext::DSC_top_level:
     case DeclSpecContext::DSC_objc_method_result:
     case DeclSpecContext::DSC_condition:
       return false;
 
     case DeclSpecContext::DSC_template_type_arg:
     case DeclSpecContext::DSC_type_specifier:
     case DeclSpecContext::DSC_trailing:
     case DeclSpecContext::DSC_alias_declaration:
       return true;
     }
     llvm_unreachable("Missing DeclSpecContext case");
   }
 
   /// Is this a context in which we can perform class template argument
   /// deduction?
   static bool isClassTemplateDeductionContext(DeclSpecContext DSC) {
     switch (DSC) {
     case DeclSpecContext::DSC_normal:
     case DeclSpecContext::DSC_template_param:
     case DeclSpecContext::DSC_class:
     case DeclSpecContext::DSC_top_level:
     case DeclSpecContext::DSC_condition:
     case DeclSpecContext::DSC_type_specifier:
       return true;
 
     case DeclSpecContext::DSC_objc_method_result:
     case DeclSpecContext::DSC_template_type_arg:
     case DeclSpecContext::DSC_trailing:
     case DeclSpecContext::DSC_alias_declaration:
       return false;
     }
     llvm_unreachable("Missing DeclSpecContext case");
   }
 
   /// Information on a C++0x for-range-initializer found while parsing a
   /// declaration which turns out to be a for-range-declaration.
   struct ForRangeInit {
     SourceLocation ColonLoc;
     ExprResult RangeExpr;
 
     bool ParsedForRangeDecl() { return !ColonLoc.isInvalid(); }
   };
   struct ForRangeInfo : ForRangeInit {
     StmtResult LoopVar;
   };
 
   DeclGroupPtrTy ParseDeclaration(DeclaratorContext Context,
                                   SourceLocation &DeclEnd,
                                   ParsedAttributesWithRange &attrs,
                                   SourceLocation *DeclSpecStart = nullptr);
   DeclGroupPtrTy
   ParseSimpleDeclaration(DeclaratorContext Context, SourceLocation &DeclEnd,
                          ParsedAttributesWithRange &attrs, bool RequireSemi,
                          ForRangeInit *FRI = nullptr,
                          SourceLocation *DeclSpecStart = nullptr);
   bool MightBeDeclarator(DeclaratorContext Context);
   DeclGroupPtrTy ParseDeclGroup(ParsingDeclSpec &DS, DeclaratorContext Context,
                                 SourceLocation *DeclEnd = nullptr,
                                 ForRangeInit *FRI = nullptr);
   Decl *ParseDeclarationAfterDeclarator(Declarator &D,
                const ParsedTemplateInfo &TemplateInfo = ParsedTemplateInfo());
   bool ParseAsmAttributesAfterDeclarator(Declarator &D);
   Decl *ParseDeclarationAfterDeclaratorAndAttributes(
       Declarator &D,
       const ParsedTemplateInfo &TemplateInfo = ParsedTemplateInfo(),
       ForRangeInit *FRI = nullptr);
   Decl *ParseFunctionStatementBody(Decl *Decl, ParseScope &BodyScope);
   Decl *ParseFunctionTryBlock(Decl *Decl, ParseScope &BodyScope);
 
   /// When in code-completion, skip parsing of the function/method body
   /// unless the body contains the code-completion point.
   ///
   /// \returns true if the function body was skipped.
   bool trySkippingFunctionBody();
 
   bool ParseImplicitInt(DeclSpec &DS, CXXScopeSpec *SS,
                         const ParsedTemplateInfo &TemplateInfo,
                         AccessSpecifier AS, DeclSpecContext DSC,
                         ParsedAttributesWithRange &Attrs);
   DeclSpecContext
   getDeclSpecContextFromDeclaratorContext(DeclaratorContext Context);
   void ParseDeclarationSpecifiers(
       DeclSpec &DS,
       const ParsedTemplateInfo &TemplateInfo = ParsedTemplateInfo(),
       AccessSpecifier AS = AS_none,
       DeclSpecContext DSC = DeclSpecContext::DSC_normal,
       LateParsedAttrList *LateAttrs = nullptr);
   bool DiagnoseMissingSemiAfterTagDefinition(
       DeclSpec &DS, AccessSpecifier AS, DeclSpecContext DSContext,
       LateParsedAttrList *LateAttrs = nullptr);
 
   void ParseSpecifierQualifierList(
       DeclSpec &DS, AccessSpecifier AS = AS_none,
       DeclSpecContext DSC = DeclSpecContext::DSC_normal);
 
   void ParseObjCTypeQualifierList(ObjCDeclSpec &DS,
                                   DeclaratorContext Context);
 
   void ParseEnumSpecifier(SourceLocation TagLoc, DeclSpec &DS,
                           const ParsedTemplateInfo &TemplateInfo,
                           AccessSpecifier AS, DeclSpecContext DSC);
   void ParseEnumBody(SourceLocation StartLoc, Decl *TagDecl);
   void ParseStructUnionBody(SourceLocation StartLoc, DeclSpec::TST TagType,
                             Decl *TagDecl);
 
   void ParseStructDeclaration(
       ParsingDeclSpec &DS,
       llvm::function_ref<void(ParsingFieldDeclarator &)> FieldsCallback);
 
   bool isDeclarationSpecifier(bool DisambiguatingWithExpression = false);
   bool isTypeSpecifierQualifier();
 
   /// isKnownToBeTypeSpecifier - Return true if we know that the specified token
   /// is definitely a type-specifier.  Return false if it isn't part of a type
   /// specifier or if we're not sure.
   bool isKnownToBeTypeSpecifier(const Token &Tok) const;
 
   /// Return true if we know that we are definitely looking at a
   /// decl-specifier, and isn't part of an expression such as a function-style
   /// cast. Return false if it's no a decl-specifier, or we're not sure.
   bool isKnownToBeDeclarationSpecifier() {
     if (getLangOpts().CPlusPlus)
       return isCXXDeclarationSpecifier() == TPResult::True;
     return isDeclarationSpecifier(true);
   }
 
   /// isDeclarationStatement - Disambiguates between a declaration or an
   /// expression statement, when parsing function bodies.
   /// Returns true for declaration, false for expression.
   bool isDeclarationStatement() {
     if (getLangOpts().CPlusPlus)
       return isCXXDeclarationStatement();
     return isDeclarationSpecifier(true);
   }
 
   /// isForInitDeclaration - Disambiguates between a declaration or an
   /// expression in the context of the C 'clause-1' or the C++
   // 'for-init-statement' part of a 'for' statement.
   /// Returns true for declaration, false for expression.
   bool isForInitDeclaration() {
     if (getLangOpts().OpenMP)
       Actions.startOpenMPLoop();
     if (getLangOpts().CPlusPlus)
       return isCXXSimpleDeclaration(/*AllowForRangeDecl=*/true);
     return isDeclarationSpecifier(true);
   }
 
   /// Determine whether this is a C++1z for-range-identifier.
   bool isForRangeIdentifier();
 
   /// Determine whether we are currently at the start of an Objective-C
   /// class message that appears to be missing the open bracket '['.
   bool isStartOfObjCClassMessageMissingOpenBracket();
 
   /// Starting with a scope specifier, identifier, or
   /// template-id that refers to the current class, determine whether
   /// this is a constructor declarator.
   bool isConstructorDeclarator(bool Unqualified, bool DeductionGuide = false);
 
   /// Specifies the context in which type-id/expression
   /// disambiguation will occur.
   enum TentativeCXXTypeIdContext {
     TypeIdInParens,
     TypeIdUnambiguous,
     TypeIdAsTemplateArgument
   };
 
 
   /// isTypeIdInParens - Assumes that a '(' was parsed and now we want to know
   /// whether the parens contain an expression or a type-id.
   /// Returns true for a type-id and false for an expression.
   bool isTypeIdInParens(bool &isAmbiguous) {
     if (getLangOpts().CPlusPlus)
       return isCXXTypeId(TypeIdInParens, isAmbiguous);
     isAmbiguous = false;
     return isTypeSpecifierQualifier();
   }
   bool isTypeIdInParens() {
     bool isAmbiguous;
     return isTypeIdInParens(isAmbiguous);
   }
 
   /// Checks if the current tokens form type-id or expression.
   /// It is similar to isTypeIdInParens but does not suppose that type-id
   /// is in parenthesis.
   bool isTypeIdUnambiguously() {
     bool IsAmbiguous;
     if (getLangOpts().CPlusPlus)
       return isCXXTypeId(TypeIdUnambiguous, IsAmbiguous);
     return isTypeSpecifierQualifier();
   }
 
   /// isCXXDeclarationStatement - C++-specialized function that disambiguates
   /// between a declaration or an expression statement, when parsing function
   /// bodies. Returns true for declaration, false for expression.
   bool isCXXDeclarationStatement();
 
   /// isCXXSimpleDeclaration - C++-specialized function that disambiguates
   /// between a simple-declaration or an expression-statement.
   /// If during the disambiguation process a parsing error is encountered,
   /// the function returns true to let the declaration parsing code handle it.
   /// Returns false if the statement is disambiguated as expression.
   bool isCXXSimpleDeclaration(bool AllowForRangeDecl);
 
   /// isCXXFunctionDeclarator - Disambiguates between a function declarator or
   /// a constructor-style initializer, when parsing declaration statements.
   /// Returns true for function declarator and false for constructor-style
   /// initializer. Sets 'IsAmbiguous' to true to indicate that this declaration
   /// might be a constructor-style initializer.
   /// If during the disambiguation process a parsing error is encountered,
   /// the function returns true to let the declaration parsing code handle it.
   bool isCXXFunctionDeclarator(bool *IsAmbiguous = nullptr);
 
   struct ConditionDeclarationOrInitStatementState;
   enum class ConditionOrInitStatement {
     Expression,    ///< Disambiguated as an expression (either kind).
     ConditionDecl, ///< Disambiguated as the declaration form of condition.
     InitStmtDecl,  ///< Disambiguated as a simple-declaration init-statement.
     ForRangeDecl,  ///< Disambiguated as a for-range declaration.
     Error          ///< Can't be any of the above!
   };
   /// Disambiguates between the different kinds of things that can happen
   /// after 'if (' or 'switch ('. This could be one of two different kinds of
   /// declaration (depending on whether there is a ';' later) or an expression.
   ConditionOrInitStatement
   isCXXConditionDeclarationOrInitStatement(bool CanBeInitStmt,
                                            bool CanBeForRangeDecl);
 
   bool isCXXTypeId(TentativeCXXTypeIdContext Context, bool &isAmbiguous);
   bool isCXXTypeId(TentativeCXXTypeIdContext Context) {
     bool isAmbiguous;
     return isCXXTypeId(Context, isAmbiguous);
   }
 
   /// TPResult - Used as the result value for functions whose purpose is to
   /// disambiguate C++ constructs by "tentatively parsing" them.
   enum class TPResult {
     True, False, Ambiguous, Error
   };
 
   /// Based only on the given token kind, determine whether we know that
   /// we're at the start of an expression or a type-specifier-seq (which may
   /// be an expression, in C++).
   ///
   /// This routine does not attempt to resolve any of the trick cases, e.g.,
   /// those involving lookup of identifiers.
   ///
   /// \returns \c TPR_true if this token starts an expression, \c TPR_false if
   /// this token starts a type-specifier-seq, or \c TPR_ambiguous if it cannot
   /// tell.
   TPResult isExpressionOrTypeSpecifierSimple(tok::TokenKind Kind);
 
   /// isCXXDeclarationSpecifier - Returns TPResult::True if it is a
   /// declaration specifier, TPResult::False if it is not,
   /// TPResult::Ambiguous if it could be either a decl-specifier or a
   /// function-style cast, and TPResult::Error if a parsing error was
   /// encountered. If it could be a braced C++11 function-style cast, returns
   /// BracedCastResult.
   /// Doesn't consume tokens.
   TPResult
   isCXXDeclarationSpecifier(TPResult BracedCastResult = TPResult::False,
                             bool *InvalidAsDeclSpec = nullptr);
 
   /// Given that isCXXDeclarationSpecifier returns \c TPResult::True or
   /// \c TPResult::Ambiguous, determine whether the decl-specifier would be
   /// a type-specifier other than a cv-qualifier.
   bool isCXXDeclarationSpecifierAType();
 
   /// Determine whether the current token sequence might be
   ///   '<' template-argument-list '>'
   /// rather than a less-than expression.
   TPResult isTemplateArgumentList(unsigned TokensToSkip);
 
   /// Determine whether an '(' after an 'explicit' keyword is part of a C++20
   /// 'explicit(bool)' declaration, in earlier language modes where that is an
   /// extension.
   TPResult isExplicitBool();
 
   /// Determine whether an identifier has been tentatively declared as a
   /// non-type. Such tentative declarations should not be found to name a type
   /// during a tentative parse, but also should not be annotated as a non-type.
   bool isTentativelyDeclared(IdentifierInfo *II);
 
   // "Tentative parsing" functions, used for disambiguation. If a parsing error
   // is encountered they will return TPResult::Error.
   // Returning TPResult::True/False indicates that the ambiguity was
   // resolved and tentative parsing may stop. TPResult::Ambiguous indicates
   // that more tentative parsing is necessary for disambiguation.
   // They all consume tokens, so backtracking should be used after calling them.
 
   TPResult TryParseSimpleDeclaration(bool AllowForRangeDecl);
   TPResult TryParseTypeofSpecifier();
   TPResult TryParseProtocolQualifiers();
   TPResult TryParsePtrOperatorSeq();
   TPResult TryParseOperatorId();
   TPResult TryParseInitDeclaratorList();
   TPResult TryParseDeclarator(bool mayBeAbstract, bool mayHaveIdentifier = true,
                               bool mayHaveDirectInit = false);
   TPResult
   TryParseParameterDeclarationClause(bool *InvalidAsDeclaration = nullptr,
                                      bool VersusTemplateArg = false);
   TPResult TryParseFunctionDeclarator();
   TPResult TryParseBracketDeclarator();
   TPResult TryConsumeDeclarationSpecifier();
 
   /// Try to skip a possibly empty sequence of 'attribute-specifier's without
   /// full validation of the syntactic structure of attributes.
   bool TrySkipAttributes();
 
 public:
   TypeResult ParseTypeName(SourceRange *Range = nullptr,
                            DeclaratorContext Context
                              = DeclaratorContext::TypeNameContext,
                            AccessSpecifier AS = AS_none,
                            Decl **OwnedType = nullptr,
                            ParsedAttributes *Attrs = nullptr);
 
 private:
   void ParseBlockId(SourceLocation CaretLoc);
 
   /// Are [[]] attributes enabled?
   bool standardAttributesAllowed() const {
     const LangOptions &LO = getLangOpts();
     return LO.DoubleSquareBracketAttributes;
   }
 
   // Check for the start of an attribute-specifier-seq in a context where an
   // attribute is not allowed.
   bool CheckProhibitedCXX11Attribute() {
     assert(Tok.is(tok::l_square));
     if (!standardAttributesAllowed() || NextToken().isNot(tok::l_square))
       return false;
     return DiagnoseProhibitedCXX11Attribute();
   }
 
   bool DiagnoseProhibitedCXX11Attribute();
   void CheckMisplacedCXX11Attribute(ParsedAttributesWithRange &Attrs,
                                     SourceLocation CorrectLocation) {
     if (!standardAttributesAllowed())
       return;
     if ((Tok.isNot(tok::l_square) || NextToken().isNot(tok::l_square)) &&
         Tok.isNot(tok::kw_alignas))
       return;
     DiagnoseMisplacedCXX11Attribute(Attrs, CorrectLocation);
   }
   void DiagnoseMisplacedCXX11Attribute(ParsedAttributesWithRange &Attrs,
                                        SourceLocation CorrectLocation);
 
   void stripTypeAttributesOffDeclSpec(ParsedAttributesWithRange &Attrs,
                                       DeclSpec &DS, Sema::TagUseKind TUK);
 
   // FixItLoc = possible correct location for the attributes
   void ProhibitAttributes(ParsedAttributesWithRange &Attrs,
                           SourceLocation FixItLoc = SourceLocation()) {
     if (Attrs.Range.isInvalid())
       return;
     DiagnoseProhibitedAttributes(Attrs.Range, FixItLoc);
     Attrs.clear();
   }
 
   void ProhibitAttributes(ParsedAttributesViewWithRange &Attrs,
                           SourceLocation FixItLoc = SourceLocation()) {
     if (Attrs.Range.isInvalid())
       return;
     DiagnoseProhibitedAttributes(Attrs.Range, FixItLoc);
     Attrs.clearListOnly();
   }
   void DiagnoseProhibitedAttributes(const SourceRange &Range,
                                     SourceLocation FixItLoc);
 
   // Forbid C++11 and C2x attributes that appear on certain syntactic locations
   // which standard permits but we don't supported yet, for example, attributes
   // appertain to decl specifiers.
   void ProhibitCXX11Attributes(ParsedAttributesWithRange &Attrs,
                                unsigned DiagID);
 
   /// Skip C++11 and C2x attributes and return the end location of the
   /// last one.
   /// \returns SourceLocation() if there are no attributes.
   SourceLocation SkipCXX11Attributes();
 
   /// Diagnose and skip C++11 and C2x attributes that appear in syntactic
   /// locations where attributes are not allowed.
   void DiagnoseAndSkipCXX11Attributes();
 
   /// Parses syntax-generic attribute arguments for attributes which are
   /// known to the implementation, and adds them to the given ParsedAttributes
   /// list with the given attribute syntax. Returns the number of arguments
   /// parsed for the attribute.
   unsigned
   ParseAttributeArgsCommon(IdentifierInfo *AttrName, SourceLocation AttrNameLoc,
                            ParsedAttributes &Attrs, SourceLocation *EndLoc,
                            IdentifierInfo *ScopeName, SourceLocation ScopeLoc,
                            ParsedAttr::Syntax Syntax);
 
   void MaybeParseGNUAttributes(Declarator &D,
                                LateParsedAttrList *LateAttrs = nullptr) {
     if (Tok.is(tok::kw___attribute)) {
       ParsedAttributes attrs(AttrFactory);
       SourceLocation endLoc;
       ParseGNUAttributes(attrs, &endLoc, LateAttrs, &D);
       D.takeAttributes(attrs, endLoc);
     }
   }
   void MaybeParseGNUAttributes(ParsedAttributes &attrs,
                                SourceLocation *endLoc = nullptr,
                                LateParsedAttrList *LateAttrs = nullptr) {
     if (Tok.is(tok::kw___attribute))
       ParseGNUAttributes(attrs, endLoc, LateAttrs);
   }
   void ParseGNUAttributes(ParsedAttributes &attrs,
                           SourceLocation *endLoc = nullptr,
                           LateParsedAttrList *LateAttrs = nullptr,
                           Declarator *D = nullptr);
   void ParseGNUAttributeArgs(IdentifierInfo *AttrName,
                              SourceLocation AttrNameLoc,
                              ParsedAttributes &Attrs, SourceLocation *EndLoc,
                              IdentifierInfo *ScopeName, SourceLocation ScopeLoc,
                              ParsedAttr::Syntax Syntax, Declarator *D);
   IdentifierLoc *ParseIdentifierLoc();
 
   unsigned
   ParseClangAttributeArgs(IdentifierInfo *AttrName, SourceLocation AttrNameLoc,
                           ParsedAttributes &Attrs, SourceLocation *EndLoc,
                           IdentifierInfo *ScopeName, SourceLocation ScopeLoc,
                           ParsedAttr::Syntax Syntax);
 
   void MaybeParseCXX11Attributes(Declarator &D) {
     if (standardAttributesAllowed() && isCXX11AttributeSpecifier()) {
       ParsedAttributesWithRange attrs(AttrFactory);
       SourceLocation endLoc;
       ParseCXX11Attributes(attrs, &endLoc);
       D.takeAttributes(attrs, endLoc);
     }
   }
   void MaybeParseCXX11Attributes(ParsedAttributes &attrs,
                                  SourceLocation *endLoc = nullptr) {
     if (standardAttributesAllowed() && isCXX11AttributeSpecifier()) {
       ParsedAttributesWithRange attrsWithRange(AttrFactory);
       ParseCXX11Attributes(attrsWithRange, endLoc);
       attrs.takeAllFrom(attrsWithRange);
     }
   }
   void MaybeParseCXX11Attributes(ParsedAttributesWithRange &attrs,
                                  SourceLocation *endLoc = nullptr,
                                  bool OuterMightBeMessageSend = false) {
     if (standardAttributesAllowed() &&
       isCXX11AttributeSpecifier(false, OuterMightBeMessageSend))
       ParseCXX11Attributes(attrs, endLoc);
   }
 
   void ParseCXX11AttributeSpecifier(ParsedAttributes &attrs,
                                     SourceLocation *EndLoc = nullptr);
   void ParseCXX11Attributes(ParsedAttributesWithRange &attrs,
                             SourceLocation *EndLoc = nullptr);
   /// Parses a C++11 (or C2x)-style attribute argument list. Returns true
   /// if this results in adding an attribute to the ParsedAttributes list.
   bool ParseCXX11AttributeArgs(IdentifierInfo *AttrName,
                                SourceLocation AttrNameLoc,
                                ParsedAttributes &Attrs, SourceLocation *EndLoc,
                                IdentifierInfo *ScopeName,
                                SourceLocation ScopeLoc);
 
   IdentifierInfo *TryParseCXX11AttributeIdentifier(SourceLocation &Loc);
 
   void MaybeParseMicrosoftAttributes(ParsedAttributes &attrs,
                                      SourceLocation *endLoc = nullptr) {
     if (getLangOpts().MicrosoftExt && Tok.is(tok::l_square))
       ParseMicrosoftAttributes(attrs, endLoc);
   }
   void ParseMicrosoftUuidAttributeArgs(ParsedAttributes &Attrs);
   void ParseMicrosoftAttributes(ParsedAttributes &attrs,
                                 SourceLocation *endLoc = nullptr);
   void MaybeParseMicrosoftDeclSpecs(ParsedAttributes &Attrs,
                                     SourceLocation *End = nullptr) {
     const auto &LO = getLangOpts();
     if (LO.DeclSpecKeyword && Tok.is(tok::kw___declspec))
       ParseMicrosoftDeclSpecs(Attrs, End);
   }
   void ParseMicrosoftDeclSpecs(ParsedAttributes &Attrs,
                                SourceLocation *End = nullptr);
   bool ParseMicrosoftDeclSpecArgs(IdentifierInfo *AttrName,
                                   SourceLocation AttrNameLoc,
                                   ParsedAttributes &Attrs);
   void ParseMicrosoftTypeAttributes(ParsedAttributes &attrs);
   void DiagnoseAndSkipExtendedMicrosoftTypeAttributes();
   SourceLocation SkipExtendedMicrosoftTypeAttributes();
   void ParseMicrosoftInheritanceClassAttributes(ParsedAttributes &attrs);
   void ParseBorlandTypeAttributes(ParsedAttributes &attrs);
   void ParseOpenCLKernelAttributes(ParsedAttributes &attrs);
   void ParseOpenCLQualifiers(ParsedAttributes &Attrs);
   /// Parses opencl_unroll_hint attribute if language is OpenCL v2.0
   /// or higher.
   /// \return false if error happens.
   bool MaybeParseOpenCLUnrollHintAttribute(ParsedAttributes &Attrs) {
     if (getLangOpts().OpenCL)
       return ParseOpenCLUnrollHintAttribute(Attrs);
     return true;
   }
   /// Parses opencl_unroll_hint attribute.
   /// \return false if error happens.
   bool ParseOpenCLUnrollHintAttribute(ParsedAttributes &Attrs);
   void ParseNullabilityTypeSpecifiers(ParsedAttributes &attrs);
 
   VersionTuple ParseVersionTuple(SourceRange &Range);
   void ParseAvailabilityAttribute(IdentifierInfo &Availability,
                                   SourceLocation AvailabilityLoc,
                                   ParsedAttributes &attrs,
                                   SourceLocation *endLoc,
                                   IdentifierInfo *ScopeName,
                                   SourceLocation ScopeLoc,
                                   ParsedAttr::Syntax Syntax);
 
   Optional<AvailabilitySpec> ParseAvailabilitySpec();
   ExprResult ParseAvailabilityCheckExpr(SourceLocation StartLoc);
 
   void ParseExternalSourceSymbolAttribute(IdentifierInfo &ExternalSourceSymbol,
                                           SourceLocation Loc,
                                           ParsedAttributes &Attrs,
                                           SourceLocation *EndLoc,
                                           IdentifierInfo *ScopeName,
                                           SourceLocation ScopeLoc,
                                           ParsedAttr::Syntax Syntax);
 
   void ParseObjCBridgeRelatedAttribute(IdentifierInfo &ObjCBridgeRelated,
                                        SourceLocation ObjCBridgeRelatedLoc,
                                        ParsedAttributes &attrs,
                                        SourceLocation *endLoc,
                                        IdentifierInfo *ScopeName,
                                        SourceLocation ScopeLoc,
                                        ParsedAttr::Syntax Syntax);
 
   void ParseTypeTagForDatatypeAttribute(IdentifierInfo &AttrName,
                                         SourceLocation AttrNameLoc,
                                         ParsedAttributes &Attrs,
                                         SourceLocation *EndLoc,
                                         IdentifierInfo *ScopeName,
                                         SourceLocation ScopeLoc,
                                         ParsedAttr::Syntax Syntax);
 
   void
   ParseAttributeWithTypeArg(IdentifierInfo &AttrName,
                             SourceLocation AttrNameLoc, ParsedAttributes &Attrs,
                             SourceLocation *EndLoc, IdentifierInfo *ScopeName,
                             SourceLocation ScopeLoc, ParsedAttr::Syntax Syntax);
 
   void ParseTypeofSpecifier(DeclSpec &DS);
   SourceLocation ParseDecltypeSpecifier(DeclSpec &DS);
   void AnnotateExistingDecltypeSpecifier(const DeclSpec &DS,
                                          SourceLocation StartLoc,
                                          SourceLocation EndLoc);
   void ParseUnderlyingTypeSpecifier(DeclSpec &DS);
   void ParseAtomicSpecifier(DeclSpec &DS);
 
   ExprResult ParseAlignArgument(SourceLocation Start,
                                 SourceLocation &EllipsisLoc);
   void ParseAlignmentSpecifier(ParsedAttributes &Attrs,
                                SourceLocation *endLoc = nullptr);
 
   VirtSpecifiers::Specifier isCXX11VirtSpecifier(const Token &Tok) const;
   VirtSpecifiers::Specifier isCXX11VirtSpecifier() const {
     return isCXX11VirtSpecifier(Tok);
   }
   void ParseOptionalCXX11VirtSpecifierSeq(VirtSpecifiers &VS, bool IsInterface,
                                           SourceLocation FriendLoc);
 
   bool isCXX11FinalKeyword() const;
 
   /// DeclaratorScopeObj - RAII object used in Parser::ParseDirectDeclarator to
   /// enter a new C++ declarator scope and exit it when the function is
   /// finished.
   class DeclaratorScopeObj {
     Parser &P;
     CXXScopeSpec &SS;
     bool EnteredScope;
     bool CreatedScope;
   public:
     DeclaratorScopeObj(Parser &p, CXXScopeSpec &ss)
       : P(p), SS(ss), EnteredScope(false), CreatedScope(false) {}
 
     void EnterDeclaratorScope() {
       assert(!EnteredScope && "Already entered the scope!");
       assert(SS.isSet() && "C++ scope was not set!");
 
       CreatedScope = true;
       P.EnterScope(0); // Not a decl scope.
 
       if (!P.Actions.ActOnCXXEnterDeclaratorScope(P.getCurScope(), SS))
         EnteredScope = true;
     }
 
     ~DeclaratorScopeObj() {
       if (EnteredScope) {
         assert(SS.isSet() && "C++ scope was cleared ?");
         P.Actions.ActOnCXXExitDeclaratorScope(P.getCurScope(), SS);
       }
       if (CreatedScope)
         P.ExitScope();
     }
   };
 
   /// ParseDeclarator - Parse and verify a newly-initialized declarator.
   void ParseDeclarator(Declarator &D);
   /// A function that parses a variant of direct-declarator.
   typedef void (Parser::*DirectDeclParseFunction)(Declarator&);
   void ParseDeclaratorInternal(Declarator &D,
                                DirectDeclParseFunction DirectDeclParser);
 
   enum AttrRequirements {
     AR_NoAttributesParsed = 0, ///< No attributes are diagnosed.
     AR_GNUAttributesParsedAndRejected = 1 << 0, ///< Diagnose GNU attributes.
     AR_GNUAttributesParsed = 1 << 1,
     AR_CXX11AttributesParsed = 1 << 2,
     AR_DeclspecAttributesParsed = 1 << 3,
     AR_AllAttributesParsed = AR_GNUAttributesParsed |
                              AR_CXX11AttributesParsed |
                              AR_DeclspecAttributesParsed,
     AR_VendorAttributesParsed = AR_GNUAttributesParsed |
                                 AR_DeclspecAttributesParsed
   };
 
   void ParseTypeQualifierListOpt(
       DeclSpec &DS, unsigned AttrReqs = AR_AllAttributesParsed,
       bool AtomicAllowed = true, bool IdentifierRequired = false,
       Optional<llvm::function_ref<void()>> CodeCompletionHandler = None);
   void ParseDirectDeclarator(Declarator &D);
   void ParseDecompositionDeclarator(Declarator &D);
   void ParseParenDeclarator(Declarator &D);
   void ParseFunctionDeclarator(Declarator &D,
                                ParsedAttributes &attrs,
                                BalancedDelimiterTracker &Tracker,
                                bool IsAmbiguous,
                                bool RequiresArg = false);
   void InitCXXThisScopeForDeclaratorIfRelevant(
       const Declarator &D, const DeclSpec &DS,
       llvm::Optional<Sema::CXXThisScopeRAII> &ThisScope);
   bool ParseRefQualifier(bool &RefQualifierIsLValueRef,
                          SourceLocation &RefQualifierLoc);
   bool isFunctionDeclaratorIdentifierList();
   void ParseFunctionDeclaratorIdentifierList(
          Declarator &D,
          SmallVectorImpl<DeclaratorChunk::ParamInfo> &ParamInfo);
   void ParseParameterDeclarationClause(
          DeclaratorContext DeclaratorContext,
          ParsedAttributes &attrs,
          SmallVectorImpl<DeclaratorChunk::ParamInfo> &ParamInfo,
          SourceLocation &EllipsisLoc);
   void ParseBracketDeclarator(Declarator &D);
   void ParseMisplacedBracketDeclarator(Declarator &D);
 
   //===--------------------------------------------------------------------===//
   // C++ 7: Declarations [dcl.dcl]
 
   /// The kind of attribute specifier we have found.
   enum CXX11AttributeKind {
     /// This is not an attribute specifier.
     CAK_NotAttributeSpecifier,
     /// This should be treated as an attribute-specifier.
     CAK_AttributeSpecifier,
     /// The next tokens are '[[', but this is not an attribute-specifier. This
     /// is ill-formed by C++11 [dcl.attr.grammar]p6.
     CAK_InvalidAttributeSpecifier
   };
   CXX11AttributeKind
   isCXX11AttributeSpecifier(bool Disambiguate = false,
                             bool OuterMightBeMessageSend = false);
 
   void DiagnoseUnexpectedNamespace(NamedDecl *Context);
 
   DeclGroupPtrTy ParseNamespace(DeclaratorContext Context,
                                 SourceLocation &DeclEnd,
                                 SourceLocation InlineLoc = SourceLocation());
 
   struct InnerNamespaceInfo {
     SourceLocation NamespaceLoc;
     SourceLocation InlineLoc;
     SourceLocation IdentLoc;
     IdentifierInfo *Ident;
   };
   using InnerNamespaceInfoList = llvm::SmallVector<InnerNamespaceInfo, 4>;
 
   void ParseInnerNamespace(const InnerNamespaceInfoList &InnerNSs,
                            unsigned int index, SourceLocation &InlineLoc,
                            ParsedAttributes &attrs,
                            BalancedDelimiterTracker &Tracker);
   Decl *ParseLinkage(ParsingDeclSpec &DS, DeclaratorContext Context);
   Decl *ParseExportDeclaration();
   DeclGroupPtrTy ParseUsingDirectiveOrDeclaration(
       DeclaratorContext Context, const ParsedTemplateInfo &TemplateInfo,
       SourceLocation &DeclEnd, ParsedAttributesWithRange &attrs);
   Decl *ParseUsingDirective(DeclaratorContext Context,
                             SourceLocation UsingLoc,
                             SourceLocation &DeclEnd,
                             ParsedAttributes &attrs);
 
   struct UsingDeclarator {
     SourceLocation TypenameLoc;
     CXXScopeSpec SS;
     UnqualifiedId Name;
     SourceLocation EllipsisLoc;
 
     void clear() {
       TypenameLoc = EllipsisLoc = SourceLocation();
       SS.clear();
       Name.clear();
     }
   };
 
   bool ParseUsingDeclarator(DeclaratorContext Context, UsingDeclarator &D);
   DeclGroupPtrTy ParseUsingDeclaration(DeclaratorContext Context,
                                        const ParsedTemplateInfo &TemplateInfo,
                                        SourceLocation UsingLoc,
                                        SourceLocation &DeclEnd,
                                        AccessSpecifier AS = AS_none);
   Decl *ParseAliasDeclarationAfterDeclarator(
       const ParsedTemplateInfo &TemplateInfo, SourceLocation UsingLoc,
       UsingDeclarator &D, SourceLocation &DeclEnd, AccessSpecifier AS,
       ParsedAttributes &Attrs, Decl **OwnedType = nullptr);
 
   Decl *ParseStaticAssertDeclaration(SourceLocation &DeclEnd);
   Decl *ParseNamespaceAlias(SourceLocation NamespaceLoc,
                             SourceLocation AliasLoc, IdentifierInfo *Alias,
                             SourceLocation &DeclEnd);
 
   //===--------------------------------------------------------------------===//
   // C++ 9: classes [class] and C structs/unions.
   bool isValidAfterTypeSpecifier(bool CouldBeBitfield);
   void ParseClassSpecifier(tok::TokenKind TagTokKind, SourceLocation TagLoc,
                            DeclSpec &DS, const ParsedTemplateInfo &TemplateInfo,
                            AccessSpecifier AS, bool EnteringContext,
                            DeclSpecContext DSC,
                            ParsedAttributesWithRange &Attributes);
   void SkipCXXMemberSpecification(SourceLocation StartLoc,
                                   SourceLocation AttrFixitLoc,
                                   unsigned TagType,
                                   Decl *TagDecl);
   void ParseCXXMemberSpecification(SourceLocation StartLoc,
                                    SourceLocation AttrFixitLoc,
                                    ParsedAttributesWithRange &Attrs,
                                    unsigned TagType,
                                    Decl *TagDecl);
   ExprResult ParseCXXMemberInitializer(Decl *D, bool IsFunction,
                                        SourceLocation &EqualLoc);
   bool
   ParseCXXMemberDeclaratorBeforeInitializer(Declarator &DeclaratorInfo,
                                             VirtSpecifiers &VS,
                                             ExprResult &BitfieldSize,
                                             LateParsedAttrList &LateAttrs);
   void MaybeParseAndDiagnoseDeclSpecAfterCXX11VirtSpecifierSeq(Declarator &D,
                                                                VirtSpecifiers &VS);
   DeclGroupPtrTy ParseCXXClassMemberDeclaration(
       AccessSpecifier AS, ParsedAttributes &Attr,
       const ParsedTemplateInfo &TemplateInfo = ParsedTemplateInfo(),
       ParsingDeclRAIIObject *DiagsFromTParams = nullptr);
   DeclGroupPtrTy ParseCXXClassMemberDeclarationWithPragmas(
       AccessSpecifier &AS, ParsedAttributesWithRange &AccessAttrs,
       DeclSpec::TST TagType, Decl *Tag);
   void ParseConstructorInitializer(Decl *ConstructorDecl);
   MemInitResult ParseMemInitializer(Decl *ConstructorDecl);
   void HandleMemberFunctionDeclDelays(Declarator& DeclaratorInfo,
                                       Decl *ThisDecl);
 
   //===--------------------------------------------------------------------===//
   // C++ 10: Derived classes [class.derived]
   TypeResult ParseBaseTypeSpecifier(SourceLocation &BaseLoc,
                                     SourceLocation &EndLocation);
   void ParseBaseClause(Decl *ClassDecl);
   BaseResult ParseBaseSpecifier(Decl *ClassDecl);
   AccessSpecifier getAccessSpecifierIfPresent() const;
 
   bool ParseUnqualifiedIdTemplateId(CXXScopeSpec &SS,
                                     SourceLocation TemplateKWLoc,
                                     IdentifierInfo *Name,
                                     SourceLocation NameLoc,
                                     bool EnteringContext,
                                     ParsedType ObjectType,
                                     UnqualifiedId &Id,
                                     bool AssumeTemplateId);
   bool ParseUnqualifiedIdOperator(CXXScopeSpec &SS, bool EnteringContext,
                                   ParsedType ObjectType,
                                   UnqualifiedId &Result);
 
   //===--------------------------------------------------------------------===//
   // OpenMP: Directives and clauses.
   /// Parse clauses for '#pragma omp declare simd'.
   DeclGroupPtrTy ParseOMPDeclareSimdClauses(DeclGroupPtrTy Ptr,
                                             CachedTokens &Toks,
                                             SourceLocation Loc);
 
   /// Parse a property kind into \p TIProperty for the selector set \p Set and
   /// selector \p Selector.
   void parseOMPTraitPropertyKind(OMPTraitInfo::OMPTraitProperty &TIProperty,
                                  llvm::omp::TraitSet Set,
                                  llvm::omp::TraitSelector Selector,
                                  llvm::StringMap<SourceLocation> &Seen);
 
   /// Parse a selector kind into \p TISelector for the selector set \p Set.
   void parseOMPTraitSelectorKind(OMPTraitInfo::OMPTraitSelector &TISelector,
                                  llvm::omp::TraitSet Set,
                                  llvm::StringMap<SourceLocation> &Seen);
 
   /// Parse a selector set kind into \p TISet.
   void parseOMPTraitSetKind(OMPTraitInfo::OMPTraitSet &TISet,
                             llvm::StringMap<SourceLocation> &Seen);
 
   /// Parses an OpenMP context property.
   void parseOMPContextProperty(OMPTraitInfo::OMPTraitSelector &TISelector,
                                llvm::omp::TraitSet Set,
                                llvm::StringMap<SourceLocation> &Seen);
 
   /// Parses an OpenMP context selector.
   void parseOMPContextSelector(OMPTraitInfo::OMPTraitSelector &TISelector,
                                llvm::omp::TraitSet Set,
                                llvm::StringMap<SourceLocation> &SeenSelectors);
 
   /// Parses an OpenMP context selector set.
   void parseOMPContextSelectorSet(OMPTraitInfo::OMPTraitSet &TISet,
                                   llvm::StringMap<SourceLocation> &SeenSets);
 
   /// Parses OpenMP context selectors.
   bool parseOMPContextSelectors(SourceLocation Loc, OMPTraitInfo &TI);
 
   /// Parse clauses for '#pragma omp declare variant'.
   void ParseOMPDeclareVariantClauses(DeclGroupPtrTy Ptr, CachedTokens &Toks,
                                      SourceLocation Loc);
   /// Parse clauses for '#pragma omp declare target'.
   DeclGroupPtrTy ParseOMPDeclareTargetClauses();
   /// Parse '#pragma omp end declare target'.
   void ParseOMPEndDeclareTargetDirective(OpenMPDirectiveKind DKind,
                                          SourceLocation Loc);
   /// Parses declarative OpenMP directives.
   DeclGroupPtrTy ParseOpenMPDeclarativeDirectiveWithExtDecl(
       AccessSpecifier &AS, ParsedAttributesWithRange &Attrs,
       bool Delayed = false, DeclSpec::TST TagType = DeclSpec::TST_unspecified,
       Decl *TagDecl = nullptr);
   /// Parse 'omp declare reduction' construct.
   DeclGroupPtrTy ParseOpenMPDeclareReductionDirective(AccessSpecifier AS);
   /// Parses initializer for provided omp_priv declaration inside the reduction
   /// initializer.
   void ParseOpenMPReductionInitializerForDecl(VarDecl *OmpPrivParm);
 
   /// Parses 'omp declare mapper' directive.
   DeclGroupPtrTy ParseOpenMPDeclareMapperDirective(AccessSpecifier AS);
   /// Parses variable declaration in 'omp declare mapper' directive.
   TypeResult parseOpenMPDeclareMapperVarDecl(SourceRange &Range,
                                              DeclarationName &Name,
                                              AccessSpecifier AS = AS_none);
 
   /// Parses simple list of variables.
   ///
   /// \param Kind Kind of the directive.
   /// \param Callback Callback function to be called for the list elements.
   /// \param AllowScopeSpecifier true, if the variables can have fully
   /// qualified names.
   ///
   bool ParseOpenMPSimpleVarList(
       OpenMPDirectiveKind Kind,
       const llvm::function_ref<void(CXXScopeSpec &, DeclarationNameInfo)> &
           Callback,
       bool AllowScopeSpecifier);
   /// Parses declarative or executable directive.
   ///
   /// \param StmtCtx The context in which we're parsing the directive.
   StmtResult
   ParseOpenMPDeclarativeOrExecutableDirective(ParsedStmtContext StmtCtx);
   /// Parses clause of kind \a CKind for directive of a kind \a Kind.
   ///
   /// \param DKind Kind of current directive.
   /// \param CKind Kind of current clause.
   /// \param FirstClause true, if this is the first clause of a kind \a CKind
   /// in current directive.
   ///
   OMPClause *ParseOpenMPClause(OpenMPDirectiveKind DKind,
                                OpenMPClauseKind CKind, bool FirstClause);
   /// Parses clause with a single expression of a kind \a Kind.
   ///
   /// \param Kind Kind of current clause.
   /// \param ParseOnly true to skip the clause's semantic actions and return
   /// nullptr.
   ///
   OMPClause *ParseOpenMPSingleExprClause(OpenMPClauseKind Kind,
                                          bool ParseOnly);
   /// Parses simple clause of a kind \a Kind.
   ///
   /// \param Kind Kind of current clause.
   /// \param ParseOnly true to skip the clause's semantic actions and return
   /// nullptr.
   ///
   OMPClause *ParseOpenMPSimpleClause(OpenMPClauseKind Kind, bool ParseOnly);
   /// Parses clause with a single expression and an additional argument
   /// of a kind \a Kind.
   ///
+  /// \param DKind Directive kind.
   /// \param Kind Kind of current clause.
   /// \param ParseOnly true to skip the clause's semantic actions and return
   /// nullptr.
   ///
-  OMPClause *ParseOpenMPSingleExprWithArgClause(OpenMPClauseKind Kind,
+  OMPClause *ParseOpenMPSingleExprWithArgClause(OpenMPDirectiveKind DKind,
+                                                OpenMPClauseKind Kind,
                                                 bool ParseOnly);
   /// Parses clause without any additional arguments.
   ///
   /// \param Kind Kind of current clause.
   /// \param ParseOnly true to skip the clause's semantic actions and return
   /// nullptr.
   ///
   OMPClause *ParseOpenMPClause(OpenMPClauseKind Kind, bool ParseOnly = false);
   /// Parses clause with the list of variables of a kind \a Kind.
   ///
   /// \param Kind Kind of current clause.
   /// \param ParseOnly true to skip the clause's semantic actions and return
   /// nullptr.
   ///
   OMPClause *ParseOpenMPVarListClause(OpenMPDirectiveKind DKind,
                                       OpenMPClauseKind Kind, bool ParseOnly);
 
 public:
   /// Parses simple expression in parens for single-expression clauses of OpenMP
   /// constructs.
   /// \param RLoc Returned location of right paren.
   ExprResult ParseOpenMPParensExpr(StringRef ClauseName, SourceLocation &RLoc,
                                    bool IsAddressOfOperand = false);
 
   /// Data used for parsing list of variables in OpenMP clauses.
   struct OpenMPVarListDataTy {
     Expr *TailExpr = nullptr;
     SourceLocation ColonLoc;
     SourceLocation RLoc;
     CXXScopeSpec ReductionOrMapperIdScopeSpec;
     DeclarationNameInfo ReductionOrMapperId;
     int ExtraModifier = -1; ///< Additional modifier for linear, map, depend or
                             ///< lastprivate clause.
     SmallVector<OpenMPMapModifierKind, OMPMapClause::NumberOfModifiers>
     MapTypeModifiers;
     SmallVector<SourceLocation, OMPMapClause::NumberOfModifiers>
     MapTypeModifiersLoc;
     bool IsMapTypeImplicit = false;
     SourceLocation DepLinMapLastLoc;
   };
 
   /// Parses clauses with list.
   bool ParseOpenMPVarList(OpenMPDirectiveKind DKind, OpenMPClauseKind Kind,
                           SmallVectorImpl<Expr *> &Vars,
                           OpenMPVarListDataTy &Data);
   bool ParseUnqualifiedId(CXXScopeSpec &SS, bool EnteringContext,
                           bool AllowDestructorName,
                           bool AllowConstructorName,
                           bool AllowDeductionGuide,
                           ParsedType ObjectType,
                           SourceLocation *TemplateKWLoc,
                           UnqualifiedId &Result);
   /// Parses the mapper modifier in map, to, and from clauses.
   bool parseMapperModifier(OpenMPVarListDataTy &Data);
   /// Parses map-type-modifiers in map clause.
   /// map([ [map-type-modifier[,] [map-type-modifier[,] ...] map-type : ] list)
   /// where, map-type-modifier ::= always | close | mapper(mapper-identifier)
   bool parseMapTypeModifiers(OpenMPVarListDataTy &Data);
 
 private:
   //===--------------------------------------------------------------------===//
   // C++ 14: Templates [temp]
 
   // C++ 14.1: Template Parameters [temp.param]
   Decl *ParseDeclarationStartingWithTemplate(DeclaratorContext Context,
                                              SourceLocation &DeclEnd,
                                              ParsedAttributes &AccessAttrs,
                                              AccessSpecifier AS = AS_none);
   Decl *ParseTemplateDeclarationOrSpecialization(DeclaratorContext Context,
                                                  SourceLocation &DeclEnd,
                                                  ParsedAttributes &AccessAttrs,
                                                  AccessSpecifier AS);
   Decl *ParseSingleDeclarationAfterTemplate(
       DeclaratorContext Context, const ParsedTemplateInfo &TemplateInfo,
       ParsingDeclRAIIObject &DiagsFromParams, SourceLocation &DeclEnd,
       ParsedAttributes &AccessAttrs, AccessSpecifier AS = AS_none);
   bool ParseTemplateParameters(unsigned Depth,
                                SmallVectorImpl<NamedDecl *> &TemplateParams,
                                SourceLocation &LAngleLoc,
                                SourceLocation &RAngleLoc);
   bool ParseTemplateParameterList(unsigned Depth,
                                   SmallVectorImpl<NamedDecl*> &TemplateParams);
   TPResult isStartOfTemplateTypeParameter();
   NamedDecl *ParseTemplateParameter(unsigned Depth, unsigned Position);
   NamedDecl *ParseTypeParameter(unsigned Depth, unsigned Position);
   NamedDecl *ParseTemplateTemplateParameter(unsigned Depth, unsigned Position);
   NamedDecl *ParseNonTypeTemplateParameter(unsigned Depth, unsigned Position);
   bool isTypeConstraintAnnotation();
   bool TryAnnotateTypeConstraint();
   NamedDecl *
   ParseConstrainedTemplateTypeParameter(unsigned Depth, unsigned Position);
   void DiagnoseMisplacedEllipsis(SourceLocation EllipsisLoc,
                                  SourceLocation CorrectLoc,
                                  bool AlreadyHasEllipsis,
                                  bool IdentifierHasName);
   void DiagnoseMisplacedEllipsisInDeclarator(SourceLocation EllipsisLoc,
                                              Declarator &D);
   // C++ 14.3: Template arguments [temp.arg]
   typedef SmallVector<ParsedTemplateArgument, 16> TemplateArgList;
 
   bool ParseGreaterThanInTemplateList(SourceLocation &RAngleLoc,
                                       bool ConsumeLastToken,
                                       bool ObjCGenericList);
   bool ParseTemplateIdAfterTemplateName(bool ConsumeLastToken,
                                         SourceLocation &LAngleLoc,
                                         TemplateArgList &TemplateArgs,
                                         SourceLocation &RAngleLoc);
 
   bool AnnotateTemplateIdToken(TemplateTy Template, TemplateNameKind TNK,
                                CXXScopeSpec &SS,
                                SourceLocation TemplateKWLoc,
                                UnqualifiedId &TemplateName,
                                bool AllowTypeAnnotation = true,
                                bool TypeConstraint = false);
   void AnnotateTemplateIdTokenAsType(CXXScopeSpec &SS,
                                      bool IsClassName = false);
   bool ParseTemplateArgumentList(TemplateArgList &TemplateArgs);
   ParsedTemplateArgument ParseTemplateTemplateArgument();
   ParsedTemplateArgument ParseTemplateArgument();
   Decl *ParseExplicitInstantiation(DeclaratorContext Context,
                                    SourceLocation ExternLoc,
                                    SourceLocation TemplateLoc,
                                    SourceLocation &DeclEnd,
                                    ParsedAttributes &AccessAttrs,
                                    AccessSpecifier AS = AS_none);
   // C++2a: Template, concept definition [temp]
   Decl *
   ParseConceptDefinition(const ParsedTemplateInfo &TemplateInfo,
                          SourceLocation &DeclEnd);
 
   //===--------------------------------------------------------------------===//
   // Modules
   DeclGroupPtrTy ParseModuleDecl(bool IsFirstDecl);
   Decl *ParseModuleImport(SourceLocation AtLoc);
   bool parseMisplacedModuleImport();
   bool tryParseMisplacedModuleImport() {
     tok::TokenKind Kind = Tok.getKind();
     if (Kind == tok::annot_module_begin || Kind == tok::annot_module_end ||
         Kind == tok::annot_module_include)
       return parseMisplacedModuleImport();
     return false;
   }
 
   bool ParseModuleName(
       SourceLocation UseLoc,
       SmallVectorImpl<std::pair<IdentifierInfo *, SourceLocation>> &Path,
       bool IsImport);
 
   //===--------------------------------------------------------------------===//
   // C++11/G++: Type Traits [Type-Traits.html in the GCC manual]
   ExprResult ParseTypeTrait();
 
   //===--------------------------------------------------------------------===//
   // Embarcadero: Arary and Expression Traits
   ExprResult ParseArrayTypeTrait();
   ExprResult ParseExpressionTrait();
 
   //===--------------------------------------------------------------------===//
   // Preprocessor code-completion pass-through
   void CodeCompleteDirective(bool InConditional) override;
   void CodeCompleteInConditionalExclusion() override;
   void CodeCompleteMacroName(bool IsDefinition) override;
   void CodeCompletePreprocessorExpression() override;
   void CodeCompleteMacroArgument(IdentifierInfo *Macro, MacroInfo *MacroInfo,
                                  unsigned ArgumentIndex) override;
   void CodeCompleteIncludedFile(llvm::StringRef Dir, bool IsAngled) override;
   void CodeCompleteNaturalLanguage() override;
 
   class GNUAsmQualifiers {
     unsigned Qualifiers = AQ_unspecified;
 
   public:
     enum AQ {
       AQ_unspecified = 0,
       AQ_volatile    = 1,
       AQ_inline      = 2,
       AQ_goto        = 4,
     };
     static const char *getQualifierName(AQ Qualifier);
     bool setAsmQualifier(AQ Qualifier);
     inline bool isVolatile() const { return Qualifiers & AQ_volatile; };
     inline bool isInline() const { return Qualifiers & AQ_inline; };
     inline bool isGoto() const { return Qualifiers & AQ_goto; }
   };
   bool isGCCAsmStatement(const Token &TokAfterAsm) const;
   bool isGNUAsmQualifier(const Token &TokAfterAsm) const;
   GNUAsmQualifiers::AQ getGNUAsmQualifier(const Token &Tok) const;
   bool parseGNUAsmQualifierListOpt(GNUAsmQualifiers &AQ);
 };
 
 }  // end namespace clang
 
 #endif
diff --git a/clang/include/clang/Sema/Sema.h b/clang/include/clang/Sema/Sema.h
index f29e4f3c227c..28f6705b307f 100644
--- a/clang/include/clang/Sema/Sema.h
+++ b/clang/include/clang/Sema/Sema.h
@@ -1,12321 +1,12323 @@
 //===--- Sema.h - Semantic Analysis & AST Building --------------*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file defines the Sema class, which performs semantic analysis and
 // builds ASTs.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef LLVM_CLANG_SEMA_SEMA_H
 #define LLVM_CLANG_SEMA_SEMA_H
 
 #include "clang/AST/ASTConcept.h"
 #include "clang/AST/ASTFwd.h"
 #include "clang/AST/Attr.h"
 #include "clang/AST/Availability.h"
 #include "clang/AST/ComparisonCategories.h"
 #include "clang/AST/DeclTemplate.h"
 #include "clang/AST/DeclarationName.h"
 #include "clang/AST/Expr.h"
 #include "clang/AST/ExprCXX.h"
 #include "clang/AST/ExprConcepts.h"
 #include "clang/AST/ExprObjC.h"
 #include "clang/AST/ExternalASTSource.h"
 #include "clang/AST/LocInfoType.h"
 #include "clang/AST/MangleNumberingContext.h"
 #include "clang/AST/NSAPI.h"
 #include "clang/AST/PrettyPrinter.h"
 #include "clang/AST/StmtCXX.h"
 #include "clang/AST/TypeLoc.h"
 #include "clang/AST/TypeOrdering.h"
 #include "clang/Basic/BitmaskEnum.h"
 #include "clang/Basic/ExpressionTraits.h"
 #include "clang/Basic/Module.h"
 #include "clang/Basic/OpenCLOptions.h"
 #include "clang/Basic/OpenMPKinds.h"
 #include "clang/Basic/PragmaKinds.h"
 #include "clang/Basic/Specifiers.h"
 #include "clang/Basic/TemplateKinds.h"
 #include "clang/Basic/TypeTraits.h"
 #include "clang/Sema/AnalysisBasedWarnings.h"
 #include "clang/Sema/CleanupInfo.h"
 #include "clang/Sema/DeclSpec.h"
 #include "clang/Sema/ExternalSemaSource.h"
 #include "clang/Sema/IdentifierResolver.h"
 #include "clang/Sema/ObjCMethodList.h"
 #include "clang/Sema/Ownership.h"
 #include "clang/Sema/Scope.h"
 #include "clang/Sema/SemaConcept.h"
 #include "clang/Sema/TypoCorrection.h"
 #include "clang/Sema/Weak.h"
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/Optional.h"
 #include "llvm/ADT/SetVector.h"
 #include "llvm/ADT/SmallBitVector.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/TinyPtrVector.h"
 #include "llvm/Frontend/OpenMP/OMPConstants.h"
 #include <deque>
 #include <memory>
 #include <string>
 #include <tuple>
 #include <vector>
 
 namespace llvm {
   class APSInt;
   template <typename ValueT> struct DenseMapInfo;
   template <typename ValueT, typename ValueInfoT> class DenseSet;
   class SmallBitVector;
   struct InlineAsmIdentifierInfo;
 }
 
 namespace clang {
   class ADLResult;
   class ASTConsumer;
   class ASTContext;
   class ASTMutationListener;
   class ASTReader;
   class ASTWriter;
   class ArrayType;
   class ParsedAttr;
   class BindingDecl;
   class BlockDecl;
   class CapturedDecl;
   class CXXBasePath;
   class CXXBasePaths;
   class CXXBindTemporaryExpr;
   typedef SmallVector<CXXBaseSpecifier*, 4> CXXCastPath;
   class CXXConstructorDecl;
   class CXXConversionDecl;
   class CXXDeleteExpr;
   class CXXDestructorDecl;
   class CXXFieldCollector;
   class CXXMemberCallExpr;
   class CXXMethodDecl;
   class CXXScopeSpec;
   class CXXTemporary;
   class CXXTryStmt;
   class CallExpr;
   class ClassTemplateDecl;
   class ClassTemplatePartialSpecializationDecl;
   class ClassTemplateSpecializationDecl;
   class VarTemplatePartialSpecializationDecl;
   class CodeCompleteConsumer;
   class CodeCompletionAllocator;
   class CodeCompletionTUInfo;
   class CodeCompletionResult;
   class CoroutineBodyStmt;
   class Decl;
   class DeclAccessPair;
   class DeclContext;
   class DeclRefExpr;
   class DeclaratorDecl;
   class DeducedTemplateArgument;
   class DependentDiagnostic;
   class DesignatedInitExpr;
   class Designation;
   class EnableIfAttr;
   class EnumConstantDecl;
   class Expr;
   class ExtVectorType;
   class FormatAttr;
   class FriendDecl;
   class FunctionDecl;
   class FunctionProtoType;
   class FunctionTemplateDecl;
   class ImplicitConversionSequence;
   typedef MutableArrayRef<ImplicitConversionSequence> ConversionSequenceList;
   class InitListExpr;
   class InitializationKind;
   class InitializationSequence;
   class InitializedEntity;
   class IntegerLiteral;
   class LabelStmt;
   class LambdaExpr;
   class LangOptions;
   class LocalInstantiationScope;
   class LookupResult;
   class MacroInfo;
   typedef ArrayRef<std::pair<IdentifierInfo *, SourceLocation>> ModuleIdPath;
   class ModuleLoader;
   class MultiLevelTemplateArgumentList;
   class NamedDecl;
   class ObjCCategoryDecl;
   class ObjCCategoryImplDecl;
   class ObjCCompatibleAliasDecl;
   class ObjCContainerDecl;
   class ObjCImplDecl;
   class ObjCImplementationDecl;
   class ObjCInterfaceDecl;
   class ObjCIvarDecl;
   template <class T> class ObjCList;
   class ObjCMessageExpr;
   class ObjCMethodDecl;
   class ObjCPropertyDecl;
   class ObjCProtocolDecl;
   class OMPThreadPrivateDecl;
   class OMPRequiresDecl;
   class OMPDeclareReductionDecl;
   class OMPDeclareSimdDecl;
   class OMPClause;
   struct OMPVarListLocTy;
   struct OverloadCandidate;
   enum class OverloadCandidateParamOrder : char;
   enum OverloadCandidateRewriteKind : unsigned;
   class OverloadCandidateSet;
   class OverloadExpr;
   class ParenListExpr;
   class ParmVarDecl;
   class Preprocessor;
   class PseudoDestructorTypeStorage;
   class PseudoObjectExpr;
   class QualType;
   class StandardConversionSequence;
   class Stmt;
   class StringLiteral;
   class SwitchStmt;
   class TemplateArgument;
   class TemplateArgumentList;
   class TemplateArgumentLoc;
   class TemplateDecl;
   class TemplateInstantiationCallback;
   class TemplateParameterList;
   class TemplatePartialOrderingContext;
   class TemplateTemplateParmDecl;
   class Token;
   class TypeAliasDecl;
   class TypedefDecl;
   class TypedefNameDecl;
   class TypeLoc;
   class TypoCorrectionConsumer;
   class UnqualifiedId;
   class UnresolvedLookupExpr;
   class UnresolvedMemberExpr;
   class UnresolvedSetImpl;
   class UnresolvedSetIterator;
   class UsingDecl;
   class UsingShadowDecl;
   class ValueDecl;
   class VarDecl;
   class VarTemplateSpecializationDecl;
   class VisibilityAttr;
   class VisibleDeclConsumer;
   class IndirectFieldDecl;
   struct DeductionFailureInfo;
   class TemplateSpecCandidateSet;
 
 namespace sema {
   class AccessedEntity;
   class BlockScopeInfo;
   class Capture;
   class CapturedRegionScopeInfo;
   class CapturingScopeInfo;
   class CompoundScopeInfo;
   class DelayedDiagnostic;
   class DelayedDiagnosticPool;
   class FunctionScopeInfo;
   class LambdaScopeInfo;
   class PossiblyUnreachableDiag;
   class SemaPPCallbacks;
   class TemplateDeductionInfo;
 }
 
 namespace threadSafety {
   class BeforeSet;
   void threadSafetyCleanup(BeforeSet* Cache);
 }
 
 // FIXME: No way to easily map from TemplateTypeParmTypes to
 // TemplateTypeParmDecls, so we have this horrible PointerUnion.
 typedef std::pair<llvm::PointerUnion<const TemplateTypeParmType*, NamedDecl*>,
                   SourceLocation> UnexpandedParameterPack;
 
 /// Describes whether we've seen any nullability information for the given
 /// file.
 struct FileNullability {
   /// The first pointer declarator (of any pointer kind) in the file that does
   /// not have a corresponding nullability annotation.
   SourceLocation PointerLoc;
 
   /// The end location for the first pointer declarator in the file. Used for
   /// placing fix-its.
   SourceLocation PointerEndLoc;
 
   /// Which kind of pointer declarator we saw.
   uint8_t PointerKind;
 
   /// Whether we saw any type nullability annotations in the given file.
   bool SawTypeNullability = false;
 };
 
 /// A mapping from file IDs to a record of whether we've seen nullability
 /// information in that file.
 class FileNullabilityMap {
   /// A mapping from file IDs to the nullability information for each file ID.
   llvm::DenseMap<FileID, FileNullability> Map;
 
   /// A single-element cache based on the file ID.
   struct {
     FileID File;
     FileNullability Nullability;
   } Cache;
 
 public:
   FileNullability &operator[](FileID file) {
     // Check the single-element cache.
     if (file == Cache.File)
       return Cache.Nullability;
 
     // It's not in the single-element cache; flush the cache if we have one.
     if (!Cache.File.isInvalid()) {
       Map[Cache.File] = Cache.Nullability;
     }
 
     // Pull this entry into the cache.
     Cache.File = file;
     Cache.Nullability = Map[file];
     return Cache.Nullability;
   }
 };
 
 /// Keeps track of expected type during expression parsing. The type is tied to
 /// a particular token, all functions that update or consume the type take a
 /// start location of the token they are looking at as a parameter. This allows
 /// to avoid updating the type on hot paths in the parser.
 class PreferredTypeBuilder {
 public:
   PreferredTypeBuilder() = default;
   explicit PreferredTypeBuilder(QualType Type) : Type(Type) {}
 
   void enterCondition(Sema &S, SourceLocation Tok);
   void enterReturn(Sema &S, SourceLocation Tok);
   void enterVariableInit(SourceLocation Tok, Decl *D);
   /// Computing a type for the function argument may require running
   /// overloading, so we postpone its computation until it is actually needed.
   ///
   /// Clients should be very careful when using this funciton, as it stores a
   /// function_ref, clients should make sure all calls to get() with the same
   /// location happen while function_ref is alive.
   void enterFunctionArgument(SourceLocation Tok,
                              llvm::function_ref<QualType()> ComputeType);
 
   void enterParenExpr(SourceLocation Tok, SourceLocation LParLoc);
   void enterUnary(Sema &S, SourceLocation Tok, tok::TokenKind OpKind,
                   SourceLocation OpLoc);
   void enterBinary(Sema &S, SourceLocation Tok, Expr *LHS, tok::TokenKind Op);
   void enterMemAccess(Sema &S, SourceLocation Tok, Expr *Base);
   void enterSubscript(Sema &S, SourceLocation Tok, Expr *LHS);
   /// Handles all type casts, including C-style cast, C++ casts, etc.
   void enterTypeCast(SourceLocation Tok, QualType CastType);
 
   QualType get(SourceLocation Tok) const {
     if (Tok != ExpectedLoc)
       return QualType();
     if (!Type.isNull())
       return Type;
     if (ComputeType)
       return ComputeType();
     return QualType();
   }
 
 private:
   /// Start position of a token for which we store expected type.
   SourceLocation ExpectedLoc;
   /// Expected type for a token starting at ExpectedLoc.
   QualType Type;
   /// A function to compute expected type at ExpectedLoc. It is only considered
   /// if Type is null.
   llvm::function_ref<QualType()> ComputeType;
 };
 
 /// Sema - This implements semantic analysis and AST building for C.
 class Sema final {
   Sema(const Sema &) = delete;
   void operator=(const Sema &) = delete;
 
   /// A key method to reduce duplicate debug info from Sema.
   virtual void anchor();
 
   ///Source of additional semantic information.
   ExternalSemaSource *ExternalSource;
 
   ///Whether Sema has generated a multiplexer and has to delete it.
   bool isMultiplexExternalSource;
 
   static bool mightHaveNonExternalLinkage(const DeclaratorDecl *FD);
 
   bool isVisibleSlow(const NamedDecl *D);
 
   /// Determine whether two declarations should be linked together, given that
   /// the old declaration might not be visible and the new declaration might
   /// not have external linkage.
   bool shouldLinkPossiblyHiddenDecl(const NamedDecl *Old,
                                     const NamedDecl *New) {
     if (isVisible(Old))
      return true;
     // See comment in below overload for why it's safe to compute the linkage
     // of the new declaration here.
     if (New->isExternallyDeclarable()) {
       assert(Old->isExternallyDeclarable() &&
              "should not have found a non-externally-declarable previous decl");
       return true;
     }
     return false;
   }
   bool shouldLinkPossiblyHiddenDecl(LookupResult &Old, const NamedDecl *New);
 
   void setupImplicitSpecialMemberType(CXXMethodDecl *SpecialMem,
                                       QualType ResultTy,
                                       ArrayRef<QualType> Args);
 
 public:
   /// The maximum alignment, same as in llvm::Value. We duplicate them here
   /// because that allows us not to duplicate the constants in clang code,
   /// which we must to since we can't directly use the llvm constants.
   /// The value is verified against llvm here: lib/CodeGen/CGDecl.cpp
   ///
   /// This is the greatest alignment value supported by load, store, and alloca
   /// instructions, and global values.
   static const unsigned MaxAlignmentExponent = 29;
   static const unsigned MaximumAlignment = 1u << MaxAlignmentExponent;
 
   typedef OpaquePtr<DeclGroupRef> DeclGroupPtrTy;
   typedef OpaquePtr<TemplateName> TemplateTy;
   typedef OpaquePtr<QualType> TypeTy;
 
   OpenCLOptions OpenCLFeatures;
   FPOptions FPFeatures;
 
   const LangOptions &LangOpts;
   Preprocessor &PP;
   ASTContext &Context;
   ASTConsumer &Consumer;
   DiagnosticsEngine &Diags;
   SourceManager &SourceMgr;
 
   /// Flag indicating whether or not to collect detailed statistics.
   bool CollectStats;
 
   /// Code-completion consumer.
   CodeCompleteConsumer *CodeCompleter;
 
   /// CurContext - This is the current declaration context of parsing.
   DeclContext *CurContext;
 
   /// Generally null except when we temporarily switch decl contexts,
   /// like in \see ActOnObjCTemporaryExitContainerContext.
   DeclContext *OriginalLexicalContext;
 
   /// VAListTagName - The declaration name corresponding to __va_list_tag.
   /// This is used as part of a hack to omit that class from ADL results.
   DeclarationName VAListTagName;
 
   bool MSStructPragmaOn; // True when \#pragma ms_struct on
 
   /// Controls member pointer representation format under the MS ABI.
   LangOptions::PragmaMSPointersToMembersKind
       MSPointerToMemberRepresentationMethod;
 
   /// Stack of active SEH __finally scopes.  Can be empty.
   SmallVector<Scope*, 2> CurrentSEHFinally;
 
   /// Source location for newly created implicit MSInheritanceAttrs
   SourceLocation ImplicitMSInheritanceAttrLoc;
 
   /// Holds TypoExprs that are created from `createDelayedTypo`. This is used by
   /// `TransformTypos` in order to keep track of any TypoExprs that are created
   /// recursively during typo correction and wipe them away if the correction
   /// fails.
   llvm::SmallVector<TypoExpr *, 2> TypoExprs;
 
   /// pragma clang section kind
   enum PragmaClangSectionKind {
     PCSK_Invalid      = 0,
     PCSK_BSS          = 1,
     PCSK_Data         = 2,
     PCSK_Rodata       = 3,
     PCSK_Text         = 4,
     PCSK_Relro        = 5
    };
 
   enum PragmaClangSectionAction {
     PCSA_Set     = 0,
     PCSA_Clear   = 1
   };
 
   struct PragmaClangSection {
     std::string SectionName;
     bool Valid = false;
     SourceLocation PragmaLocation;
 
     void Act(SourceLocation PragmaLocation,
              PragmaClangSectionAction Action,
              StringLiteral* Name);
    };
 
    PragmaClangSection PragmaClangBSSSection;
    PragmaClangSection PragmaClangDataSection;
    PragmaClangSection PragmaClangRodataSection;
    PragmaClangSection PragmaClangRelroSection;
    PragmaClangSection PragmaClangTextSection;
 
   enum PragmaMsStackAction {
     PSK_Reset     = 0x0,                // #pragma ()
     PSK_Set       = 0x1,                // #pragma (value)
     PSK_Push      = 0x2,                // #pragma (push[, id])
     PSK_Pop       = 0x4,                // #pragma (pop[, id])
     PSK_Show      = 0x8,                // #pragma (show) -- only for "pack"!
     PSK_Push_Set  = PSK_Push | PSK_Set, // #pragma (push[, id], value)
     PSK_Pop_Set   = PSK_Pop | PSK_Set,  // #pragma (pop[, id], value)
   };
 
   template<typename ValueType>
   struct PragmaStack {
     struct Slot {
       llvm::StringRef StackSlotLabel;
       ValueType Value;
       SourceLocation PragmaLocation;
       SourceLocation PragmaPushLocation;
       Slot(llvm::StringRef StackSlotLabel, ValueType Value,
            SourceLocation PragmaLocation, SourceLocation PragmaPushLocation)
           : StackSlotLabel(StackSlotLabel), Value(Value),
             PragmaLocation(PragmaLocation),
             PragmaPushLocation(PragmaPushLocation) {}
     };
     void Act(SourceLocation PragmaLocation,
              PragmaMsStackAction Action,
              llvm::StringRef StackSlotLabel,
              ValueType Value);
 
     // MSVC seems to add artificial slots to #pragma stacks on entering a C++
     // method body to restore the stacks on exit, so it works like this:
     //
     //   struct S {
     //     #pragma <name>(push, InternalPragmaSlot, <current_pragma_value>)
     //     void Method {}
     //     #pragma <name>(pop, InternalPragmaSlot)
     //   };
     //
     // It works even with #pragma vtordisp, although MSVC doesn't support
     //   #pragma vtordisp(push [, id], n)
     // syntax.
     //
     // Push / pop a named sentinel slot.
     void SentinelAction(PragmaMsStackAction Action, StringRef Label) {
       assert((Action == PSK_Push || Action == PSK_Pop) &&
              "Can only push / pop #pragma stack sentinels!");
       Act(CurrentPragmaLocation, Action, Label, CurrentValue);
     }
 
     // Constructors.
     explicit PragmaStack(const ValueType &Default)
         : DefaultValue(Default), CurrentValue(Default) {}
 
     bool hasValue() const { return CurrentValue != DefaultValue; }
 
     SmallVector<Slot, 2> Stack;
     ValueType DefaultValue; // Value used for PSK_Reset action.
     ValueType CurrentValue;
     SourceLocation CurrentPragmaLocation;
   };
   // FIXME: We should serialize / deserialize these if they occur in a PCH (but
   // we shouldn't do so if they're in a module).
 
   /// Whether to insert vtordisps prior to virtual bases in the Microsoft
   /// C++ ABI.  Possible values are 0, 1, and 2, which mean:
   ///
   /// 0: Suppress all vtordisps
   /// 1: Insert vtordisps in the presence of vbase overrides and non-trivial
   ///    structors
   /// 2: Always insert vtordisps to support RTTI on partially constructed
   ///    objects
   PragmaStack<MSVtorDispMode> VtorDispStack;
   // #pragma pack.
   // Sentinel to represent when the stack is set to mac68k alignment.
   static const unsigned kMac68kAlignmentSentinel = ~0U;
   PragmaStack<unsigned> PackStack;
   // The current #pragma pack values and locations at each #include.
   struct PackIncludeState {
     unsigned CurrentValue;
     SourceLocation CurrentPragmaLocation;
     bool HasNonDefaultValue, ShouldWarnOnInclude;
   };
   SmallVector<PackIncludeState, 8> PackIncludeStack;
   // Segment #pragmas.
   PragmaStack<StringLiteral *> DataSegStack;
   PragmaStack<StringLiteral *> BSSSegStack;
   PragmaStack<StringLiteral *> ConstSegStack;
   PragmaStack<StringLiteral *> CodeSegStack;
 
   // RAII object to push / pop sentinel slots for all MS #pragma stacks.
   // Actions should be performed only if we enter / exit a C++ method body.
   class PragmaStackSentinelRAII {
   public:
     PragmaStackSentinelRAII(Sema &S, StringRef SlotLabel, bool ShouldAct);
     ~PragmaStackSentinelRAII();
 
   private:
     Sema &S;
     StringRef SlotLabel;
     bool ShouldAct;
   };
 
   /// A mapping that describes the nullability we've seen in each header file.
   FileNullabilityMap NullabilityMap;
 
   /// Last section used with #pragma init_seg.
   StringLiteral *CurInitSeg;
   SourceLocation CurInitSegLoc;
 
   /// VisContext - Manages the stack for \#pragma GCC visibility.
   void *VisContext; // Really a "PragmaVisStack*"
 
   /// This an attribute introduced by \#pragma clang attribute.
   struct PragmaAttributeEntry {
     SourceLocation Loc;
     ParsedAttr *Attribute;
     SmallVector<attr::SubjectMatchRule, 4> MatchRules;
     bool IsUsed;
   };
 
   /// A push'd group of PragmaAttributeEntries.
   struct PragmaAttributeGroup {
     /// The location of the push attribute.
     SourceLocation Loc;
     /// The namespace of this push group.
     const IdentifierInfo *Namespace;
     SmallVector<PragmaAttributeEntry, 2> Entries;
   };
 
   SmallVector<PragmaAttributeGroup, 2> PragmaAttributeStack;
 
   /// The declaration that is currently receiving an attribute from the
   /// #pragma attribute stack.
   const Decl *PragmaAttributeCurrentTargetDecl;
 
   /// This represents the last location of a "#pragma clang optimize off"
   /// directive if such a directive has not been closed by an "on" yet. If
   /// optimizations are currently "on", this is set to an invalid location.
   SourceLocation OptimizeOffPragmaLocation;
 
   /// Flag indicating if Sema is building a recovery call expression.
   ///
   /// This flag is used to avoid building recovery call expressions
   /// if Sema is already doing so, which would cause infinite recursions.
   bool IsBuildingRecoveryCallExpr;
 
   /// Used to control the generation of ExprWithCleanups.
   CleanupInfo Cleanup;
 
   /// ExprCleanupObjects - This is the stack of objects requiring
   /// cleanup that are created by the current full expression.
   SmallVector<ExprWithCleanups::CleanupObject, 8> ExprCleanupObjects;
 
   /// Store a set of either DeclRefExprs or MemberExprs that contain a reference
   /// to a variable (constant) that may or may not be odr-used in this Expr, and
   /// we won't know until all lvalue-to-rvalue and discarded value conversions
   /// have been applied to all subexpressions of the enclosing full expression.
   /// This is cleared at the end of each full expression.
   using MaybeODRUseExprSet = llvm::SmallPtrSet<Expr *, 2>;
   MaybeODRUseExprSet MaybeODRUseExprs;
 
   std::unique_ptr<sema::FunctionScopeInfo> CachedFunctionScope;
 
   /// Stack containing information about each of the nested
   /// function, block, and method scopes that are currently active.
   SmallVector<sema::FunctionScopeInfo *, 4> FunctionScopes;
 
   /// The index of the first FunctionScope that corresponds to the current
   /// context.
   unsigned FunctionScopesStart = 0;
 
   ArrayRef<sema::FunctionScopeInfo*> getFunctionScopes() const {
     return llvm::makeArrayRef(FunctionScopes.begin() + FunctionScopesStart,
                               FunctionScopes.end());
   }
 
   /// Stack containing information needed when in C++2a an 'auto' is encountered
   /// in a function declaration parameter type specifier in order to invent a
   /// corresponding template parameter in the enclosing abbreviated function
   /// template. This information is also present in LambdaScopeInfo, stored in
   /// the FunctionScopes stack.
   SmallVector<InventedTemplateParameterInfo, 4> InventedParameterInfos;
 
   /// The index of the first InventedParameterInfo that refers to the current
   /// context.
   unsigned InventedParameterInfosStart = 0;
 
   ArrayRef<InventedTemplateParameterInfo> getInventedParameterInfos() const {
     return llvm::makeArrayRef(InventedParameterInfos.begin() +
                                   InventedParameterInfosStart,
                               InventedParameterInfos.end());
   }
 
   typedef LazyVector<TypedefNameDecl *, ExternalSemaSource,
                      &ExternalSemaSource::ReadExtVectorDecls, 2, 2>
     ExtVectorDeclsType;
 
   /// ExtVectorDecls - This is a list all the extended vector types. This allows
   /// us to associate a raw vector type with one of the ext_vector type names.
   /// This is only necessary for issuing pretty diagnostics.
   ExtVectorDeclsType ExtVectorDecls;
 
   /// FieldCollector - Collects CXXFieldDecls during parsing of C++ classes.
   std::unique_ptr<CXXFieldCollector> FieldCollector;
 
   typedef llvm::SmallSetVector<NamedDecl *, 16> NamedDeclSetType;
 
   /// Set containing all declared private fields that are not used.
   NamedDeclSetType UnusedPrivateFields;
 
   /// Set containing all typedefs that are likely unused.
   llvm::SmallSetVector<const TypedefNameDecl *, 4>
       UnusedLocalTypedefNameCandidates;
 
   /// Delete-expressions to be analyzed at the end of translation unit
   ///
   /// This list contains class members, and locations of delete-expressions
   /// that could not be proven as to whether they mismatch with new-expression
   /// used in initializer of the field.
   typedef std::pair<SourceLocation, bool> DeleteExprLoc;
   typedef llvm::SmallVector<DeleteExprLoc, 4> DeleteLocs;
   llvm::MapVector<FieldDecl *, DeleteLocs> DeleteExprs;
 
   typedef llvm::SmallPtrSet<const CXXRecordDecl*, 8> RecordDeclSetTy;
 
   /// PureVirtualClassDiagSet - a set of class declarations which we have
   /// emitted a list of pure virtual functions. Used to prevent emitting the
   /// same list more than once.
   std::unique_ptr<RecordDeclSetTy> PureVirtualClassDiagSet;
 
   /// ParsingInitForAutoVars - a set of declarations with auto types for which
   /// we are currently parsing the initializer.
   llvm::SmallPtrSet<const Decl*, 4> ParsingInitForAutoVars;
 
   /// Look for a locally scoped extern "C" declaration by the given name.
   NamedDecl *findLocallyScopedExternCDecl(DeclarationName Name);
 
   typedef LazyVector<VarDecl *, ExternalSemaSource,
                      &ExternalSemaSource::ReadTentativeDefinitions, 2, 2>
     TentativeDefinitionsType;
 
   /// All the tentative definitions encountered in the TU.
   TentativeDefinitionsType TentativeDefinitions;
 
   /// All the external declarations encoutered and used in the TU.
   SmallVector<VarDecl *, 4> ExternalDeclarations;
 
   typedef LazyVector<const DeclaratorDecl *, ExternalSemaSource,
                      &ExternalSemaSource::ReadUnusedFileScopedDecls, 2, 2>
     UnusedFileScopedDeclsType;
 
   /// The set of file scoped decls seen so far that have not been used
   /// and must warn if not used. Only contains the first declaration.
   UnusedFileScopedDeclsType UnusedFileScopedDecls;
 
   typedef LazyVector<CXXConstructorDecl *, ExternalSemaSource,
                      &ExternalSemaSource::ReadDelegatingConstructors, 2, 2>
     DelegatingCtorDeclsType;
 
   /// All the delegating constructors seen so far in the file, used for
   /// cycle detection at the end of the TU.
   DelegatingCtorDeclsType DelegatingCtorDecls;
 
   /// All the overriding functions seen during a class definition
   /// that had their exception spec checks delayed, plus the overridden
   /// function.
   SmallVector<std::pair<const CXXMethodDecl*, const CXXMethodDecl*>, 2>
     DelayedOverridingExceptionSpecChecks;
 
   /// All the function redeclarations seen during a class definition that had
   /// their exception spec checks delayed, plus the prior declaration they
   /// should be checked against. Except during error recovery, the new decl
   /// should always be a friend declaration, as that's the only valid way to
   /// redeclare a special member before its class is complete.
   SmallVector<std::pair<FunctionDecl*, FunctionDecl*>, 2>
     DelayedEquivalentExceptionSpecChecks;
 
   typedef llvm::MapVector<const FunctionDecl *,
                           std::unique_ptr<LateParsedTemplate>>
       LateParsedTemplateMapT;
   LateParsedTemplateMapT LateParsedTemplateMap;
 
   /// Callback to the parser to parse templated functions when needed.
   typedef void LateTemplateParserCB(void *P, LateParsedTemplate &LPT);
   typedef void LateTemplateParserCleanupCB(void *P);
   LateTemplateParserCB *LateTemplateParser;
   LateTemplateParserCleanupCB *LateTemplateParserCleanup;
   void *OpaqueParser;
 
   void SetLateTemplateParser(LateTemplateParserCB *LTP,
                              LateTemplateParserCleanupCB *LTPCleanup,
                              void *P) {
     LateTemplateParser = LTP;
     LateTemplateParserCleanup = LTPCleanup;
     OpaqueParser = P;
   }
 
   class DelayedDiagnostics;
 
   class DelayedDiagnosticsState {
     sema::DelayedDiagnosticPool *SavedPool;
     friend class Sema::DelayedDiagnostics;
   };
   typedef DelayedDiagnosticsState ParsingDeclState;
   typedef DelayedDiagnosticsState ProcessingContextState;
 
   /// A class which encapsulates the logic for delaying diagnostics
   /// during parsing and other processing.
   class DelayedDiagnostics {
     /// The current pool of diagnostics into which delayed
     /// diagnostics should go.
     sema::DelayedDiagnosticPool *CurPool;
 
   public:
     DelayedDiagnostics() : CurPool(nullptr) {}
 
     /// Adds a delayed diagnostic.
     void add(const sema::DelayedDiagnostic &diag); // in DelayedDiagnostic.h
 
     /// Determines whether diagnostics should be delayed.
     bool shouldDelayDiagnostics() { return CurPool != nullptr; }
 
     /// Returns the current delayed-diagnostics pool.
     sema::DelayedDiagnosticPool *getCurrentPool() const {
       return CurPool;
     }
 
     /// Enter a new scope.  Access and deprecation diagnostics will be
     /// collected in this pool.
     DelayedDiagnosticsState push(sema::DelayedDiagnosticPool &pool) {
       DelayedDiagnosticsState state;
       state.SavedPool = CurPool;
       CurPool = &pool;
       return state;
     }
 
     /// Leave a delayed-diagnostic state that was previously pushed.
     /// Do not emit any of the diagnostics.  This is performed as part
     /// of the bookkeeping of popping a pool "properly".
     void popWithoutEmitting(DelayedDiagnosticsState state) {
       CurPool = state.SavedPool;
     }
 
     /// Enter a new scope where access and deprecation diagnostics are
     /// not delayed.
     DelayedDiagnosticsState pushUndelayed() {
       DelayedDiagnosticsState state;
       state.SavedPool = CurPool;
       CurPool = nullptr;
       return state;
     }
 
     /// Undo a previous pushUndelayed().
     void popUndelayed(DelayedDiagnosticsState state) {
       assert(CurPool == nullptr);
       CurPool = state.SavedPool;
     }
   } DelayedDiagnostics;
 
   /// A RAII object to temporarily push a declaration context.
   class ContextRAII {
   private:
     Sema &S;
     DeclContext *SavedContext;
     ProcessingContextState SavedContextState;
     QualType SavedCXXThisTypeOverride;
     unsigned SavedFunctionScopesStart;
     unsigned SavedInventedParameterInfosStart;
 
   public:
     ContextRAII(Sema &S, DeclContext *ContextToPush, bool NewThisContext = true)
       : S(S), SavedContext(S.CurContext),
         SavedContextState(S.DelayedDiagnostics.pushUndelayed()),
         SavedCXXThisTypeOverride(S.CXXThisTypeOverride),
         SavedFunctionScopesStart(S.FunctionScopesStart),
         SavedInventedParameterInfosStart(S.InventedParameterInfosStart)
     {
       assert(ContextToPush && "pushing null context");
       S.CurContext = ContextToPush;
       if (NewThisContext)
         S.CXXThisTypeOverride = QualType();
       // Any saved FunctionScopes do not refer to this context.
       S.FunctionScopesStart = S.FunctionScopes.size();
       S.InventedParameterInfosStart = S.InventedParameterInfos.size();
     }
 
     void pop() {
       if (!SavedContext) return;
       S.CurContext = SavedContext;
       S.DelayedDiagnostics.popUndelayed(SavedContextState);
       S.CXXThisTypeOverride = SavedCXXThisTypeOverride;
       S.FunctionScopesStart = SavedFunctionScopesStart;
       S.InventedParameterInfosStart = SavedInventedParameterInfosStart;
       SavedContext = nullptr;
     }
 
     ~ContextRAII() {
       pop();
     }
   };
 
   /// Whether the AST is currently being rebuilt to correct immediate
   /// invocations. Immediate invocation candidates and references to consteval
   /// functions aren't tracked when this is set.
   bool RebuildingImmediateInvocation = false;
 
   /// Used to change context to isConstantEvaluated without pushing a heavy
   /// ExpressionEvaluationContextRecord object.
   bool isConstantEvaluatedOverride;
 
   bool isConstantEvaluated() {
     return ExprEvalContexts.back().isConstantEvaluated() ||
            isConstantEvaluatedOverride;
   }
 
   /// RAII object to handle the state changes required to synthesize
   /// a function body.
   class SynthesizedFunctionScope {
     Sema &S;
     Sema::ContextRAII SavedContext;
     bool PushedCodeSynthesisContext = false;
 
   public:
     SynthesizedFunctionScope(Sema &S, DeclContext *DC)
         : S(S), SavedContext(S, DC) {
       S.PushFunctionScope();
       S.PushExpressionEvaluationContext(
           Sema::ExpressionEvaluationContext::PotentiallyEvaluated);
       if (auto *FD = dyn_cast<FunctionDecl>(DC))
         FD->setWillHaveBody(true);
       else
         assert(isa<ObjCMethodDecl>(DC));
     }
 
     void addContextNote(SourceLocation UseLoc) {
       assert(!PushedCodeSynthesisContext);
 
       Sema::CodeSynthesisContext Ctx;
       Ctx.Kind = Sema::CodeSynthesisContext::DefiningSynthesizedFunction;
       Ctx.PointOfInstantiation = UseLoc;
       Ctx.Entity = cast<Decl>(S.CurContext);
       S.pushCodeSynthesisContext(Ctx);
 
       PushedCodeSynthesisContext = true;
     }
 
     ~SynthesizedFunctionScope() {
       if (PushedCodeSynthesisContext)
         S.popCodeSynthesisContext();
       if (auto *FD = dyn_cast<FunctionDecl>(S.CurContext))
         FD->setWillHaveBody(false);
       S.PopExpressionEvaluationContext();
       S.PopFunctionScopeInfo();
     }
   };
 
   /// WeakUndeclaredIdentifiers - Identifiers contained in
   /// \#pragma weak before declared. rare. may alias another
   /// identifier, declared or undeclared
   llvm::MapVector<IdentifierInfo *, WeakInfo> WeakUndeclaredIdentifiers;
 
   /// ExtnameUndeclaredIdentifiers - Identifiers contained in
   /// \#pragma redefine_extname before declared.  Used in Solaris system headers
   /// to define functions that occur in multiple standards to call the version
   /// in the currently selected standard.
   llvm::DenseMap<IdentifierInfo*,AsmLabelAttr*> ExtnameUndeclaredIdentifiers;
 
 
   /// Load weak undeclared identifiers from the external source.
   void LoadExternalWeakUndeclaredIdentifiers();
 
   /// WeakTopLevelDecl - Translation-unit scoped declarations generated by
   /// \#pragma weak during processing of other Decls.
   /// I couldn't figure out a clean way to generate these in-line, so
   /// we store them here and handle separately -- which is a hack.
   /// It would be best to refactor this.
   SmallVector<Decl*,2> WeakTopLevelDecl;
 
   IdentifierResolver IdResolver;
 
   /// Translation Unit Scope - useful to Objective-C actions that need
   /// to lookup file scope declarations in the "ordinary" C decl namespace.
   /// For example, user-defined classes, built-in "id" type, etc.
   Scope *TUScope;
 
   /// The C++ "std" namespace, where the standard library resides.
   LazyDeclPtr StdNamespace;
 
   /// The C++ "std::bad_alloc" class, which is defined by the C++
   /// standard library.
   LazyDeclPtr StdBadAlloc;
 
   /// The C++ "std::align_val_t" enum class, which is defined by the C++
   /// standard library.
   LazyDeclPtr StdAlignValT;
 
   /// The C++ "std::experimental" namespace, where the experimental parts
   /// of the standard library resides.
   NamespaceDecl *StdExperimentalNamespaceCache;
 
   /// The C++ "std::initializer_list" template, which is defined in
   /// \<initializer_list>.
   ClassTemplateDecl *StdInitializerList;
 
   /// The C++ "std::coroutine_traits" template, which is defined in
   /// \<coroutine_traits>
   ClassTemplateDecl *StdCoroutineTraitsCache;
 
   /// The C++ "type_info" declaration, which is defined in \<typeinfo>.
   RecordDecl *CXXTypeInfoDecl;
 
   /// The MSVC "_GUID" struct, which is defined in MSVC header files.
   RecordDecl *MSVCGuidDecl;
 
   /// Caches identifiers/selectors for NSFoundation APIs.
   std::unique_ptr<NSAPI> NSAPIObj;
 
   /// The declaration of the Objective-C NSNumber class.
   ObjCInterfaceDecl *NSNumberDecl;
 
   /// The declaration of the Objective-C NSValue class.
   ObjCInterfaceDecl *NSValueDecl;
 
   /// Pointer to NSNumber type (NSNumber *).
   QualType NSNumberPointer;
 
   /// Pointer to NSValue type (NSValue *).
   QualType NSValuePointer;
 
   /// The Objective-C NSNumber methods used to create NSNumber literals.
   ObjCMethodDecl *NSNumberLiteralMethods[NSAPI::NumNSNumberLiteralMethods];
 
   /// The declaration of the Objective-C NSString class.
   ObjCInterfaceDecl *NSStringDecl;
 
   /// Pointer to NSString type (NSString *).
   QualType NSStringPointer;
 
   /// The declaration of the stringWithUTF8String: method.
   ObjCMethodDecl *StringWithUTF8StringMethod;
 
   /// The declaration of the valueWithBytes:objCType: method.
   ObjCMethodDecl *ValueWithBytesObjCTypeMethod;
 
   /// The declaration of the Objective-C NSArray class.
   ObjCInterfaceDecl *NSArrayDecl;
 
   /// The declaration of the arrayWithObjects:count: method.
   ObjCMethodDecl *ArrayWithObjectsMethod;
 
   /// The declaration of the Objective-C NSDictionary class.
   ObjCInterfaceDecl *NSDictionaryDecl;
 
   /// The declaration of the dictionaryWithObjects:forKeys:count: method.
   ObjCMethodDecl *DictionaryWithObjectsMethod;
 
   /// id<NSCopying> type.
   QualType QIDNSCopying;
 
   /// will hold 'respondsToSelector:'
   Selector RespondsToSelectorSel;
 
   /// A flag to remember whether the implicit forms of operator new and delete
   /// have been declared.
   bool GlobalNewDeleteDeclared;
 
   /// A flag to indicate that we're in a context that permits abstract
   /// references to fields.  This is really a
   bool AllowAbstractFieldReference;
 
   /// Describes how the expressions currently being parsed are
   /// evaluated at run-time, if at all.
   enum class ExpressionEvaluationContext {
     /// The current expression and its subexpressions occur within an
     /// unevaluated operand (C++11 [expr]p7), such as the subexpression of
     /// \c sizeof, where the type of the expression may be significant but
     /// no code will be generated to evaluate the value of the expression at
     /// run time.
     Unevaluated,
 
     /// The current expression occurs within a braced-init-list within
     /// an unevaluated operand. This is mostly like a regular unevaluated
     /// context, except that we still instantiate constexpr functions that are
     /// referenced here so that we can perform narrowing checks correctly.
     UnevaluatedList,
 
     /// The current expression occurs within a discarded statement.
     /// This behaves largely similarly to an unevaluated operand in preventing
     /// definitions from being required, but not in other ways.
     DiscardedStatement,
 
     /// The current expression occurs within an unevaluated
     /// operand that unconditionally permits abstract references to
     /// fields, such as a SIZE operator in MS-style inline assembly.
     UnevaluatedAbstract,
 
     /// The current context is "potentially evaluated" in C++11 terms,
     /// but the expression is evaluated at compile-time (like the values of
     /// cases in a switch statement).
     ConstantEvaluated,
 
     /// The current expression is potentially evaluated at run time,
     /// which means that code may be generated to evaluate the value of the
     /// expression at run time.
     PotentiallyEvaluated,
 
     /// The current expression is potentially evaluated, but any
     /// declarations referenced inside that expression are only used if
     /// in fact the current expression is used.
     ///
     /// This value is used when parsing default function arguments, for which
     /// we would like to provide diagnostics (e.g., passing non-POD arguments
     /// through varargs) but do not want to mark declarations as "referenced"
     /// until the default argument is used.
     PotentiallyEvaluatedIfUsed
   };
 
   using ImmediateInvocationCandidate = llvm::PointerIntPair<ConstantExpr *, 1>;
 
   /// Data structure used to record current or nested
   /// expression evaluation contexts.
   struct ExpressionEvaluationContextRecord {
     /// The expression evaluation context.
     ExpressionEvaluationContext Context;
 
     /// Whether the enclosing context needed a cleanup.
     CleanupInfo ParentCleanup;
 
     /// Whether we are in a decltype expression.
     bool IsDecltype;
 
     /// The number of active cleanup objects when we entered
     /// this expression evaluation context.
     unsigned NumCleanupObjects;
 
     /// The number of typos encountered during this expression evaluation
     /// context (i.e. the number of TypoExprs created).
     unsigned NumTypos;
 
     MaybeODRUseExprSet SavedMaybeODRUseExprs;
 
     /// The lambdas that are present within this context, if it
     /// is indeed an unevaluated context.
     SmallVector<LambdaExpr *, 2> Lambdas;
 
     /// The declaration that provides context for lambda expressions
     /// and block literals if the normal declaration context does not
     /// suffice, e.g., in a default function argument.
     Decl *ManglingContextDecl;
 
     /// If we are processing a decltype type, a set of call expressions
     /// for which we have deferred checking the completeness of the return type.
     SmallVector<CallExpr *, 8> DelayedDecltypeCalls;
 
     /// If we are processing a decltype type, a set of temporary binding
     /// expressions for which we have deferred checking the destructor.
     SmallVector<CXXBindTemporaryExpr *, 8> DelayedDecltypeBinds;
 
     llvm::SmallPtrSet<const Expr *, 8> PossibleDerefs;
 
     /// Expressions appearing as the LHS of a volatile assignment in this
     /// context. We produce a warning for these when popping the context if
     /// they are not discarded-value expressions nor unevaluated operands.
     SmallVector<Expr*, 2> VolatileAssignmentLHSs;
 
     /// Set of candidates for starting an immediate invocation.
     llvm::SmallVector<ImmediateInvocationCandidate, 4> ImmediateInvocationCandidates;
 
     /// Set of DeclRefExprs referencing a consteval function when used in a
     /// context not already known to be immediately invoked.
     llvm::SmallPtrSet<DeclRefExpr *, 4> ReferenceToConsteval;
 
     /// \brief Describes whether we are in an expression constext which we have
     /// to handle differently.
     enum ExpressionKind {
       EK_Decltype, EK_TemplateArgument, EK_Other
     } ExprContext;
 
     ExpressionEvaluationContextRecord(ExpressionEvaluationContext Context,
                                       unsigned NumCleanupObjects,
                                       CleanupInfo ParentCleanup,
                                       Decl *ManglingContextDecl,
                                       ExpressionKind ExprContext)
         : Context(Context), ParentCleanup(ParentCleanup),
           NumCleanupObjects(NumCleanupObjects), NumTypos(0),
           ManglingContextDecl(ManglingContextDecl), ExprContext(ExprContext) {}
 
     bool isUnevaluated() const {
       return Context == ExpressionEvaluationContext::Unevaluated ||
              Context == ExpressionEvaluationContext::UnevaluatedAbstract ||
              Context == ExpressionEvaluationContext::UnevaluatedList;
     }
     bool isConstantEvaluated() const {
       return Context == ExpressionEvaluationContext::ConstantEvaluated;
     }
   };
 
   /// A stack of expression evaluation contexts.
   SmallVector<ExpressionEvaluationContextRecord, 8> ExprEvalContexts;
 
   /// Emit a warning for all pending noderef expressions that we recorded.
   void WarnOnPendingNoDerefs(ExpressionEvaluationContextRecord &Rec);
 
   /// Compute the mangling number context for a lambda expression or
   /// block literal. Also return the extra mangling decl if any.
   ///
   /// \param DC - The DeclContext containing the lambda expression or
   /// block literal.
   std::tuple<MangleNumberingContext *, Decl *>
   getCurrentMangleNumberContext(const DeclContext *DC);
 
 
   /// SpecialMemberOverloadResult - The overloading result for a special member
   /// function.
   ///
   /// This is basically a wrapper around PointerIntPair. The lowest bits of the
   /// integer are used to determine whether overload resolution succeeded.
   class SpecialMemberOverloadResult {
   public:
     enum Kind {
       NoMemberOrDeleted,
       Ambiguous,
       Success
     };
 
   private:
     llvm::PointerIntPair<CXXMethodDecl*, 2> Pair;
 
   public:
     SpecialMemberOverloadResult() : Pair() {}
     SpecialMemberOverloadResult(CXXMethodDecl *MD)
         : Pair(MD, MD->isDeleted() ? NoMemberOrDeleted : Success) {}
 
     CXXMethodDecl *getMethod() const { return Pair.getPointer(); }
     void setMethod(CXXMethodDecl *MD) { Pair.setPointer(MD); }
 
     Kind getKind() const { return static_cast<Kind>(Pair.getInt()); }
     void setKind(Kind K) { Pair.setInt(K); }
   };
 
   class SpecialMemberOverloadResultEntry
       : public llvm::FastFoldingSetNode,
         public SpecialMemberOverloadResult {
   public:
     SpecialMemberOverloadResultEntry(const llvm::FoldingSetNodeID &ID)
       : FastFoldingSetNode(ID)
     {}
   };
 
   /// A cache of special member function overload resolution results
   /// for C++ records.
   llvm::FoldingSet<SpecialMemberOverloadResultEntry> SpecialMemberCache;
 
   /// A cache of the flags available in enumerations with the flag_bits
   /// attribute.
   mutable llvm::DenseMap<const EnumDecl*, llvm::APInt> FlagBitsCache;
 
   /// The kind of translation unit we are processing.
   ///
   /// When we're processing a complete translation unit, Sema will perform
   /// end-of-translation-unit semantic tasks (such as creating
   /// initializers for tentative definitions in C) once parsing has
   /// completed. Modules and precompiled headers perform different kinds of
   /// checks.
   TranslationUnitKind TUKind;
 
   llvm::BumpPtrAllocator BumpAlloc;
 
   /// The number of SFINAE diagnostics that have been trapped.
   unsigned NumSFINAEErrors;
 
   typedef llvm::DenseMap<ParmVarDecl *, llvm::TinyPtrVector<ParmVarDecl *>>
     UnparsedDefaultArgInstantiationsMap;
 
   /// A mapping from parameters with unparsed default arguments to the
   /// set of instantiations of each parameter.
   ///
   /// This mapping is a temporary data structure used when parsing
   /// nested class templates or nested classes of class templates,
   /// where we might end up instantiating an inner class before the
   /// default arguments of its methods have been parsed.
   UnparsedDefaultArgInstantiationsMap UnparsedDefaultArgInstantiations;
 
   // Contains the locations of the beginning of unparsed default
   // argument locations.
   llvm::DenseMap<ParmVarDecl *, SourceLocation> UnparsedDefaultArgLocs;
 
   /// UndefinedInternals - all the used, undefined objects which require a
   /// definition in this translation unit.
   llvm::MapVector<NamedDecl *, SourceLocation> UndefinedButUsed;
 
   /// Determine if VD, which must be a variable or function, is an external
   /// symbol that nonetheless can't be referenced from outside this translation
   /// unit because its type has no linkage and it's not extern "C".
   bool isExternalWithNoLinkageType(ValueDecl *VD);
 
   /// Obtain a sorted list of functions that are undefined but ODR-used.
   void getUndefinedButUsed(
       SmallVectorImpl<std::pair<NamedDecl *, SourceLocation> > &Undefined);
 
   /// Retrieves list of suspicious delete-expressions that will be checked at
   /// the end of translation unit.
   const llvm::MapVector<FieldDecl *, DeleteLocs> &
   getMismatchingDeleteExpressions() const;
 
   typedef std::pair<ObjCMethodList, ObjCMethodList> GlobalMethods;
   typedef llvm::DenseMap<Selector, GlobalMethods> GlobalMethodPool;
 
   /// Method Pool - allows efficient lookup when typechecking messages to "id".
   /// We need to maintain a list, since selectors can have differing signatures
   /// across classes. In Cocoa, this happens to be extremely uncommon (only 1%
   /// of selectors are "overloaded").
   /// At the head of the list it is recorded whether there were 0, 1, or >= 2
   /// methods inside categories with a particular selector.
   GlobalMethodPool MethodPool;
 
   /// Method selectors used in a \@selector expression. Used for implementation
   /// of -Wselector.
   llvm::MapVector<Selector, SourceLocation> ReferencedSelectors;
 
   /// List of SourceLocations where 'self' is implicitly retained inside a
   /// block.
   llvm::SmallVector<std::pair<SourceLocation, const BlockDecl *>, 1>
       ImplicitlyRetainedSelfLocs;
 
   /// Kinds of C++ special members.
   enum CXXSpecialMember {
     CXXDefaultConstructor,
     CXXCopyConstructor,
     CXXMoveConstructor,
     CXXCopyAssignment,
     CXXMoveAssignment,
     CXXDestructor,
     CXXInvalid
   };
 
   typedef llvm::PointerIntPair<CXXRecordDecl *, 3, CXXSpecialMember>
       SpecialMemberDecl;
 
   /// The C++ special members which we are currently in the process of
   /// declaring. If this process recursively triggers the declaration of the
   /// same special member, we should act as if it is not yet declared.
   llvm::SmallPtrSet<SpecialMemberDecl, 4> SpecialMembersBeingDeclared;
 
   /// Kinds of defaulted comparison operator functions.
   enum class DefaultedComparisonKind : unsigned char {
     /// This is not a defaultable comparison operator.
     None,
     /// This is an operator== that should be implemented as a series of
     /// subobject comparisons.
     Equal,
     /// This is an operator<=> that should be implemented as a series of
     /// subobject comparisons.
     ThreeWay,
     /// This is an operator!= that should be implemented as a rewrite in terms
     /// of a == comparison.
     NotEqual,
     /// This is an <, <=, >, or >= that should be implemented as a rewrite in
     /// terms of a <=> comparison.
     Relational,
   };
 
   /// The function definitions which were renamed as part of typo-correction
   /// to match their respective declarations. We want to keep track of them
   /// to ensure that we don't emit a "redefinition" error if we encounter a
   /// correctly named definition after the renamed definition.
   llvm::SmallPtrSet<const NamedDecl *, 4> TypoCorrectedFunctionDefinitions;
 
   /// Stack of types that correspond to the parameter entities that are
   /// currently being copy-initialized. Can be empty.
   llvm::SmallVector<QualType, 4> CurrentParameterCopyTypes;
 
   void ReadMethodPool(Selector Sel);
   void updateOutOfDateSelector(Selector Sel);
 
   /// Private Helper predicate to check for 'self'.
   bool isSelfExpr(Expr *RExpr);
   bool isSelfExpr(Expr *RExpr, const ObjCMethodDecl *Method);
 
   /// Cause the active diagnostic on the DiagosticsEngine to be
   /// emitted. This is closely coupled to the SemaDiagnosticBuilder class and
   /// should not be used elsewhere.
   void EmitCurrentDiagnostic(unsigned DiagID);
 
   /// Records and restores the FPFeatures state on entry/exit of compound
   /// statements.
   class FPFeaturesStateRAII {
   public:
     FPFeaturesStateRAII(Sema &S) : S(S), OldFPFeaturesState(S.FPFeatures) {}
     ~FPFeaturesStateRAII() { S.FPFeatures = OldFPFeaturesState; }
 
   private:
     Sema& S;
     FPOptions OldFPFeaturesState;
   };
 
   void addImplicitTypedef(StringRef Name, QualType T);
 
   bool WarnedStackExhausted = false;
 
 public:
   Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer,
        TranslationUnitKind TUKind = TU_Complete,
        CodeCompleteConsumer *CompletionConsumer = nullptr);
   ~Sema();
 
   /// Perform initialization that occurs after the parser has been
   /// initialized but before it parses anything.
   void Initialize();
 
   const LangOptions &getLangOpts() const { return LangOpts; }
   OpenCLOptions &getOpenCLOptions() { return OpenCLFeatures; }
   FPOptions     &getFPOptions() { return FPFeatures; }
 
   DiagnosticsEngine &getDiagnostics() const { return Diags; }
   SourceManager &getSourceManager() const { return SourceMgr; }
   Preprocessor &getPreprocessor() const { return PP; }
   ASTContext &getASTContext() const { return Context; }
   ASTConsumer &getASTConsumer() const { return Consumer; }
   ASTMutationListener *getASTMutationListener() const;
   ExternalSemaSource* getExternalSource() const { return ExternalSource; }
 
   ///Registers an external source. If an external source already exists,
   /// creates a multiplex external source and appends to it.
   ///
   ///\param[in] E - A non-null external sema source.
   ///
   void addExternalSource(ExternalSemaSource *E);
 
   void PrintStats() const;
 
   /// Warn that the stack is nearly exhausted.
   void warnStackExhausted(SourceLocation Loc);
 
   /// Run some code with "sufficient" stack space. (Currently, at least 256K is
   /// guaranteed). Produces a warning if we're low on stack space and allocates
   /// more in that case. Use this in code that may recurse deeply (for example,
   /// in template instantiation) to avoid stack overflow.
   void runWithSufficientStackSpace(SourceLocation Loc,
                                    llvm::function_ref<void()> Fn);
 
   /// Helper class that creates diagnostics with optional
   /// template instantiation stacks.
   ///
   /// This class provides a wrapper around the basic DiagnosticBuilder
   /// class that emits diagnostics. SemaDiagnosticBuilder is
   /// responsible for emitting the diagnostic (as DiagnosticBuilder
   /// does) and, if the diagnostic comes from inside a template
   /// instantiation, printing the template instantiation stack as
   /// well.
   class SemaDiagnosticBuilder : public DiagnosticBuilder {
     Sema &SemaRef;
     unsigned DiagID;
 
   public:
     SemaDiagnosticBuilder(DiagnosticBuilder &DB, Sema &SemaRef, unsigned DiagID)
       : DiagnosticBuilder(DB), SemaRef(SemaRef), DiagID(DiagID) { }
 
     // This is a cunning lie. DiagnosticBuilder actually performs move
     // construction in its copy constructor (but due to varied uses, it's not
     // possible to conveniently express this as actual move construction). So
     // the default copy ctor here is fine, because the base class disables the
     // source anyway, so the user-defined ~SemaDiagnosticBuilder is a safe no-op
     // in that case anwyay.
     SemaDiagnosticBuilder(const SemaDiagnosticBuilder&) = default;
 
     ~SemaDiagnosticBuilder() {
       // If we aren't active, there is nothing to do.
       if (!isActive()) return;
 
       // Otherwise, we need to emit the diagnostic. First flush the underlying
       // DiagnosticBuilder data, and clear the diagnostic builder itself so it
       // won't emit the diagnostic in its own destructor.
       //
       // This seems wasteful, in that as written the DiagnosticBuilder dtor will
       // do its own needless checks to see if the diagnostic needs to be
       // emitted. However, because we take care to ensure that the builder
       // objects never escape, a sufficiently smart compiler will be able to
       // eliminate that code.
       FlushCounts();
       Clear();
 
       // Dispatch to Sema to emit the diagnostic.
       SemaRef.EmitCurrentDiagnostic(DiagID);
     }
 
     /// Teach operator<< to produce an object of the correct type.
     template<typename T>
     friend const SemaDiagnosticBuilder &operator<<(
         const SemaDiagnosticBuilder &Diag, const T &Value) {
       const DiagnosticBuilder &BaseDiag = Diag;
       BaseDiag << Value;
       return Diag;
     }
   };
 
   /// Emit a diagnostic.
   SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID) {
     DiagnosticBuilder DB = Diags.Report(Loc, DiagID);
     return SemaDiagnosticBuilder(DB, *this, DiagID);
   }
 
   /// Emit a partial diagnostic.
   SemaDiagnosticBuilder Diag(SourceLocation Loc, const PartialDiagnostic& PD);
 
   /// Build a partial diagnostic.
   PartialDiagnostic PDiag(unsigned DiagID = 0); // in SemaInternal.h
 
   bool findMacroSpelling(SourceLocation &loc, StringRef name);
 
   /// Get a string to suggest for zero-initialization of a type.
   std::string
   getFixItZeroInitializerForType(QualType T, SourceLocation Loc) const;
   std::string getFixItZeroLiteralForType(QualType T, SourceLocation Loc) const;
 
   /// Calls \c Lexer::getLocForEndOfToken()
   SourceLocation getLocForEndOfToken(SourceLocation Loc, unsigned Offset = 0);
 
   /// Retrieve the module loader associated with the preprocessor.
   ModuleLoader &getModuleLoader() const;
 
   /// Invent a new identifier for parameters of abbreviated templates.
   IdentifierInfo *
   InventAbbreviatedTemplateParameterTypeName(IdentifierInfo *ParamName,
                                              unsigned Index);
 
   void emitAndClearUnusedLocalTypedefWarnings();
 
   enum TUFragmentKind {
     /// The global module fragment, between 'module;' and a module-declaration.
     Global,
     /// A normal translation unit fragment. For a non-module unit, this is the
     /// entire translation unit. Otherwise, it runs from the module-declaration
     /// to the private-module-fragment (if any) or the end of the TU (if not).
     Normal,
     /// The private module fragment, between 'module :private;' and the end of
     /// the translation unit.
     Private
   };
 
   void ActOnStartOfTranslationUnit();
   void ActOnEndOfTranslationUnit();
   void ActOnEndOfTranslationUnitFragment(TUFragmentKind Kind);
 
   void CheckDelegatingCtorCycles();
 
   Scope *getScopeForContext(DeclContext *Ctx);
 
   void PushFunctionScope();
   void PushBlockScope(Scope *BlockScope, BlockDecl *Block);
   sema::LambdaScopeInfo *PushLambdaScope();
 
   /// This is used to inform Sema what the current TemplateParameterDepth
   /// is during Parsing.  Currently it is used to pass on the depth
   /// when parsing generic lambda 'auto' parameters.
   void RecordParsingTemplateParameterDepth(unsigned Depth);
 
   void PushCapturedRegionScope(Scope *RegionScope, CapturedDecl *CD,
                                RecordDecl *RD, CapturedRegionKind K,
                                unsigned OpenMPCaptureLevel = 0);
 
   /// Custom deleter to allow FunctionScopeInfos to be kept alive for a short
   /// time after they've been popped.
   class PoppedFunctionScopeDeleter {
     Sema *Self;
 
   public:
     explicit PoppedFunctionScopeDeleter(Sema *Self) : Self(Self) {}
     void operator()(sema::FunctionScopeInfo *Scope) const;
   };
 
   using PoppedFunctionScopePtr =
       std::unique_ptr<sema::FunctionScopeInfo, PoppedFunctionScopeDeleter>;
 
   PoppedFunctionScopePtr
   PopFunctionScopeInfo(const sema::AnalysisBasedWarnings::Policy *WP = nullptr,
                        const Decl *D = nullptr,
                        QualType BlockType = QualType());
 
   sema::FunctionScopeInfo *getCurFunction() const {
     return FunctionScopes.empty() ? nullptr : FunctionScopes.back();
   }
 
   sema::FunctionScopeInfo *getEnclosingFunction() const;
 
   void setFunctionHasBranchIntoScope();
   void setFunctionHasBranchProtectedScope();
   void setFunctionHasIndirectGoto();
 
   void PushCompoundScope(bool IsStmtExpr);
   void PopCompoundScope();
 
   sema::CompoundScopeInfo &getCurCompoundScope() const;
 
   bool hasAnyUnrecoverableErrorsInThisFunction() const;
 
   /// Retrieve the current block, if any.
   sema::BlockScopeInfo *getCurBlock();
 
   /// Get the innermost lambda enclosing the current location, if any. This
   /// looks through intervening non-lambda scopes such as local functions and
   /// blocks.
   sema::LambdaScopeInfo *getEnclosingLambda() const;
 
   /// Retrieve the current lambda scope info, if any.
   /// \param IgnoreNonLambdaCapturingScope true if should find the top-most
   /// lambda scope info ignoring all inner capturing scopes that are not
   /// lambda scopes.
   sema::LambdaScopeInfo *
   getCurLambda(bool IgnoreNonLambdaCapturingScope = false);
 
   /// Retrieve the current generic lambda info, if any.
   sema::LambdaScopeInfo *getCurGenericLambda();
 
   /// Retrieve the current captured region, if any.
   sema::CapturedRegionScopeInfo *getCurCapturedRegion();
 
   /// WeakTopLevelDeclDecls - access to \#pragma weak-generated Decls
   SmallVectorImpl<Decl *> &WeakTopLevelDecls() { return WeakTopLevelDecl; }
 
   /// Called before parsing a function declarator belonging to a function
   /// declaration.
   void ActOnStartFunctionDeclarationDeclarator(Declarator &D,
                                                unsigned TemplateParameterDepth);
 
   /// Called after parsing a function declarator belonging to a function
   /// declaration.
   void ActOnFinishFunctionDeclarationDeclarator(Declarator &D);
 
   void ActOnComment(SourceRange Comment);
 
   //===--------------------------------------------------------------------===//
   // Type Analysis / Processing: SemaType.cpp.
   //
 
   QualType BuildQualifiedType(QualType T, SourceLocation Loc, Qualifiers Qs,
                               const DeclSpec *DS = nullptr);
   QualType BuildQualifiedType(QualType T, SourceLocation Loc, unsigned CVRA,
                               const DeclSpec *DS = nullptr);
   QualType BuildPointerType(QualType T,
                             SourceLocation Loc, DeclarationName Entity);
   QualType BuildReferenceType(QualType T, bool LValueRef,
                               SourceLocation Loc, DeclarationName Entity);
   QualType BuildArrayType(QualType T, ArrayType::ArraySizeModifier ASM,
                           Expr *ArraySize, unsigned Quals,
                           SourceRange Brackets, DeclarationName Entity);
   QualType BuildVectorType(QualType T, Expr *VecSize, SourceLocation AttrLoc);
   QualType BuildExtVectorType(QualType T, Expr *ArraySize,
                               SourceLocation AttrLoc);
   QualType BuildAddressSpaceAttr(QualType &T, LangAS ASIdx, Expr *AddrSpace,
                                  SourceLocation AttrLoc);
 
   /// Same as above, but constructs the AddressSpace index if not provided.
   QualType BuildAddressSpaceAttr(QualType &T, Expr *AddrSpace,
                                  SourceLocation AttrLoc);
 
   bool CheckQualifiedFunctionForTypeId(QualType T, SourceLocation Loc);
 
   bool CheckFunctionReturnType(QualType T, SourceLocation Loc);
 
   /// Build a function type.
   ///
   /// This routine checks the function type according to C++ rules and
   /// under the assumption that the result type and parameter types have
   /// just been instantiated from a template. It therefore duplicates
   /// some of the behavior of GetTypeForDeclarator, but in a much
   /// simpler form that is only suitable for this narrow use case.
   ///
   /// \param T The return type of the function.
   ///
   /// \param ParamTypes The parameter types of the function. This array
   /// will be modified to account for adjustments to the types of the
   /// function parameters.
   ///
   /// \param Loc The location of the entity whose type involves this
   /// function type or, if there is no such entity, the location of the
   /// type that will have function type.
   ///
   /// \param Entity The name of the entity that involves the function
   /// type, if known.
   ///
   /// \param EPI Extra information about the function type. Usually this will
   /// be taken from an existing function with the same prototype.
   ///
   /// \returns A suitable function type, if there are no errors. The
   /// unqualified type will always be a FunctionProtoType.
   /// Otherwise, returns a NULL type.
   QualType BuildFunctionType(QualType T,
                              MutableArrayRef<QualType> ParamTypes,
                              SourceLocation Loc, DeclarationName Entity,
                              const FunctionProtoType::ExtProtoInfo &EPI);
 
   QualType BuildMemberPointerType(QualType T, QualType Class,
                                   SourceLocation Loc,
                                   DeclarationName Entity);
   QualType BuildBlockPointerType(QualType T,
                                  SourceLocation Loc, DeclarationName Entity);
   QualType BuildParenType(QualType T);
   QualType BuildAtomicType(QualType T, SourceLocation Loc);
   QualType BuildReadPipeType(QualType T,
                          SourceLocation Loc);
   QualType BuildWritePipeType(QualType T,
                          SourceLocation Loc);
 
   TypeSourceInfo *GetTypeForDeclarator(Declarator &D, Scope *S);
   TypeSourceInfo *GetTypeForDeclaratorCast(Declarator &D, QualType FromTy);
 
   /// Package the given type and TSI into a ParsedType.
   ParsedType CreateParsedType(QualType T, TypeSourceInfo *TInfo);
   DeclarationNameInfo GetNameForDeclarator(Declarator &D);
   DeclarationNameInfo GetNameFromUnqualifiedId(const UnqualifiedId &Name);
   static QualType GetTypeFromParser(ParsedType Ty,
                                     TypeSourceInfo **TInfo = nullptr);
   CanThrowResult canThrow(const Stmt *E);
   const FunctionProtoType *ResolveExceptionSpec(SourceLocation Loc,
                                                 const FunctionProtoType *FPT);
   void UpdateExceptionSpec(FunctionDecl *FD,
                            const FunctionProtoType::ExceptionSpecInfo &ESI);
   bool CheckSpecifiedExceptionType(QualType &T, SourceRange Range);
   bool CheckDistantExceptionSpec(QualType T);
   bool CheckEquivalentExceptionSpec(FunctionDecl *Old, FunctionDecl *New);
   bool CheckEquivalentExceptionSpec(
       const FunctionProtoType *Old, SourceLocation OldLoc,
       const FunctionProtoType *New, SourceLocation NewLoc);
   bool CheckEquivalentExceptionSpec(
       const PartialDiagnostic &DiagID, const PartialDiagnostic & NoteID,
       const FunctionProtoType *Old, SourceLocation OldLoc,
       const FunctionProtoType *New, SourceLocation NewLoc);
   bool handlerCanCatch(QualType HandlerType, QualType ExceptionType);
   bool CheckExceptionSpecSubset(const PartialDiagnostic &DiagID,
                                 const PartialDiagnostic &NestedDiagID,
                                 const PartialDiagnostic &NoteID,
                                 const PartialDiagnostic &NoThrowDiagID,
                                 const FunctionProtoType *Superset,
                                 SourceLocation SuperLoc,
                                 const FunctionProtoType *Subset,
                                 SourceLocation SubLoc);
   bool CheckParamExceptionSpec(const PartialDiagnostic &NestedDiagID,
                                const PartialDiagnostic &NoteID,
                                const FunctionProtoType *Target,
                                SourceLocation TargetLoc,
                                const FunctionProtoType *Source,
                                SourceLocation SourceLoc);
 
   TypeResult ActOnTypeName(Scope *S, Declarator &D);
 
   /// The parser has parsed the context-sensitive type 'instancetype'
   /// in an Objective-C message declaration. Return the appropriate type.
   ParsedType ActOnObjCInstanceType(SourceLocation Loc);
 
   /// Abstract class used to diagnose incomplete types.
   struct TypeDiagnoser {
     TypeDiagnoser() {}
 
     virtual void diagnose(Sema &S, SourceLocation Loc, QualType T) = 0;
     virtual ~TypeDiagnoser() {}
   };
 
   static int getPrintable(int I) { return I; }
   static unsigned getPrintable(unsigned I) { return I; }
   static bool getPrintable(bool B) { return B; }
   static const char * getPrintable(const char *S) { return S; }
   static StringRef getPrintable(StringRef S) { return S; }
   static const std::string &getPrintable(const std::string &S) { return S; }
   static const IdentifierInfo *getPrintable(const IdentifierInfo *II) {
     return II;
   }
   static DeclarationName getPrintable(DeclarationName N) { return N; }
   static QualType getPrintable(QualType T) { return T; }
   static SourceRange getPrintable(SourceRange R) { return R; }
   static SourceRange getPrintable(SourceLocation L) { return L; }
   static SourceRange getPrintable(const Expr *E) { return E->getSourceRange(); }
   static SourceRange getPrintable(TypeLoc TL) { return TL.getSourceRange();}
 
   template <typename... Ts> class BoundTypeDiagnoser : public TypeDiagnoser {
   protected:
     unsigned DiagID;
     std::tuple<const Ts &...> Args;
 
     template <std::size_t... Is>
     void emit(const SemaDiagnosticBuilder &DB,
               std::index_sequence<Is...>) const {
       // Apply all tuple elements to the builder in order.
       bool Dummy[] = {false, (DB << getPrintable(std::get<Is>(Args)))...};
       (void)Dummy;
     }
 
   public:
     BoundTypeDiagnoser(unsigned DiagID, const Ts &...Args)
         : TypeDiagnoser(), DiagID(DiagID), Args(Args...) {
       assert(DiagID != 0 && "no diagnostic for type diagnoser");
     }
 
     void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
       const SemaDiagnosticBuilder &DB = S.Diag(Loc, DiagID);
       emit(DB, std::index_sequence_for<Ts...>());
       DB << T;
     }
   };
 
   /// A derivative of BoundTypeDiagnoser for which the diagnostic's type
   /// parameter is preceded by a 0/1 enum that is 1 if the type is sizeless.
   /// For example, a diagnostic with no other parameters would generally have
   /// the form "...%select{incomplete|sizeless}0 type %1...".
   template <typename... Ts>
   class SizelessTypeDiagnoser : public BoundTypeDiagnoser<Ts...> {
   public:
     SizelessTypeDiagnoser(unsigned DiagID, const Ts &... Args)
         : BoundTypeDiagnoser<Ts...>(DiagID, Args...) {}
 
     void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
       const SemaDiagnosticBuilder &DB = S.Diag(Loc, this->DiagID);
       this->emit(DB, std::index_sequence_for<Ts...>());
       DB << T->isSizelessType() << T;
     }
   };
 
   enum class CompleteTypeKind {
     /// Apply the normal rules for complete types.  In particular,
     /// treat all sizeless types as incomplete.
     Normal,
 
     /// Relax the normal rules for complete types so that they include
     /// sizeless built-in types.
     AcceptSizeless,
 
     // FIXME: Eventually we should flip the default to Normal and opt in
     // to AcceptSizeless rather than opt out of it.
     Default = AcceptSizeless
   };
 
 private:
   /// Methods for marking which expressions involve dereferencing a pointer
   /// marked with the 'noderef' attribute. Expressions are checked bottom up as
   /// they are parsed, meaning that a noderef pointer may not be accessed. For
   /// example, in `&*p` where `p` is a noderef pointer, we will first parse the
   /// `*p`, but need to check that `address of` is called on it. This requires
   /// keeping a container of all pending expressions and checking if the address
   /// of them are eventually taken.
   void CheckSubscriptAccessOfNoDeref(const ArraySubscriptExpr *E);
   void CheckAddressOfNoDeref(const Expr *E);
   void CheckMemberAccessOfNoDeref(const MemberExpr *E);
 
   bool RequireCompleteTypeImpl(SourceLocation Loc, QualType T,
                                CompleteTypeKind Kind, TypeDiagnoser *Diagnoser);
 
   struct ModuleScope {
     SourceLocation BeginLoc;
     clang::Module *Module = nullptr;
     bool ModuleInterface = false;
     bool ImplicitGlobalModuleFragment = false;
     VisibleModuleSet OuterVisibleModules;
   };
   /// The modules we're currently parsing.
   llvm::SmallVector<ModuleScope, 16> ModuleScopes;
 
   /// Namespace definitions that we will export when they finish.
   llvm::SmallPtrSet<const NamespaceDecl*, 8> DeferredExportedNamespaces;
 
   /// Get the module whose scope we are currently within.
   Module *getCurrentModule() const {
     return ModuleScopes.empty() ? nullptr : ModuleScopes.back().Module;
   }
 
   VisibleModuleSet VisibleModules;
 
 public:
   /// Get the module owning an entity.
   Module *getOwningModule(const Decl *Entity) {
     return Entity->getOwningModule();
   }
 
   /// Make a merged definition of an existing hidden definition \p ND
   /// visible at the specified location.
   void makeMergedDefinitionVisible(NamedDecl *ND);
 
   bool isModuleVisible(const Module *M, bool ModulePrivate = false);
 
   /// Determine whether a declaration is visible to name lookup.
   bool isVisible(const NamedDecl *D) {
     return !D->isHidden() || isVisibleSlow(D);
   }
 
   /// Determine whether any declaration of an entity is visible.
   bool
   hasVisibleDeclaration(const NamedDecl *D,
                         llvm::SmallVectorImpl<Module *> *Modules = nullptr) {
     return isVisible(D) || hasVisibleDeclarationSlow(D, Modules);
   }
   bool hasVisibleDeclarationSlow(const NamedDecl *D,
                                  llvm::SmallVectorImpl<Module *> *Modules);
 
   bool hasVisibleMergedDefinition(NamedDecl *Def);
   bool hasMergedDefinitionInCurrentModule(NamedDecl *Def);
 
   /// Determine if \p D and \p Suggested have a structurally compatible
   /// layout as described in C11 6.2.7/1.
   bool hasStructuralCompatLayout(Decl *D, Decl *Suggested);
 
   /// Determine if \p D has a visible definition. If not, suggest a declaration
   /// that should be made visible to expose the definition.
   bool hasVisibleDefinition(NamedDecl *D, NamedDecl **Suggested,
                             bool OnlyNeedComplete = false);
   bool hasVisibleDefinition(const NamedDecl *D) {
     NamedDecl *Hidden;
     return hasVisibleDefinition(const_cast<NamedDecl*>(D), &Hidden);
   }
 
   /// Determine if the template parameter \p D has a visible default argument.
   bool
   hasVisibleDefaultArgument(const NamedDecl *D,
                             llvm::SmallVectorImpl<Module *> *Modules = nullptr);
 
   /// Determine if there is a visible declaration of \p D that is an explicit
   /// specialization declaration for a specialization of a template. (For a
   /// member specialization, use hasVisibleMemberSpecialization.)
   bool hasVisibleExplicitSpecialization(
       const NamedDecl *D, llvm::SmallVectorImpl<Module *> *Modules = nullptr);
 
   /// Determine if there is a visible declaration of \p D that is a member
   /// specialization declaration (as opposed to an instantiated declaration).
   bool hasVisibleMemberSpecialization(
       const NamedDecl *D, llvm::SmallVectorImpl<Module *> *Modules = nullptr);
 
   /// Determine if \p A and \p B are equivalent internal linkage declarations
   /// from different modules, and thus an ambiguity error can be downgraded to
   /// an extension warning.
   bool isEquivalentInternalLinkageDeclaration(const NamedDecl *A,
                                               const NamedDecl *B);
   void diagnoseEquivalentInternalLinkageDeclarations(
       SourceLocation Loc, const NamedDecl *D,
       ArrayRef<const NamedDecl *> Equiv);
 
   bool isUsualDeallocationFunction(const CXXMethodDecl *FD);
 
   bool isCompleteType(SourceLocation Loc, QualType T,
                       CompleteTypeKind Kind = CompleteTypeKind::Default) {
     return !RequireCompleteTypeImpl(Loc, T, Kind, nullptr);
   }
   bool RequireCompleteType(SourceLocation Loc, QualType T,
                            CompleteTypeKind Kind, TypeDiagnoser &Diagnoser);
   bool RequireCompleteType(SourceLocation Loc, QualType T,
                            CompleteTypeKind Kind, unsigned DiagID);
 
   bool RequireCompleteType(SourceLocation Loc, QualType T,
                            TypeDiagnoser &Diagnoser) {
     return RequireCompleteType(Loc, T, CompleteTypeKind::Default, Diagnoser);
   }
   bool RequireCompleteType(SourceLocation Loc, QualType T, unsigned DiagID) {
     return RequireCompleteType(Loc, T, CompleteTypeKind::Default, DiagID);
   }
 
   template <typename... Ts>
   bool RequireCompleteType(SourceLocation Loc, QualType T, unsigned DiagID,
                            const Ts &...Args) {
     BoundTypeDiagnoser<Ts...> Diagnoser(DiagID, Args...);
     return RequireCompleteType(Loc, T, Diagnoser);
   }
 
   template <typename... Ts>
   bool RequireCompleteSizedType(SourceLocation Loc, QualType T, unsigned DiagID,
                                 const Ts &... Args) {
     SizelessTypeDiagnoser<Ts...> Diagnoser(DiagID, Args...);
     return RequireCompleteType(Loc, T, CompleteTypeKind::Normal, Diagnoser);
   }
 
   void completeExprArrayBound(Expr *E);
   bool RequireCompleteExprType(Expr *E, CompleteTypeKind Kind,
                                TypeDiagnoser &Diagnoser);
   bool RequireCompleteExprType(Expr *E, unsigned DiagID);
 
   template <typename... Ts>
   bool RequireCompleteExprType(Expr *E, unsigned DiagID, const Ts &...Args) {
     BoundTypeDiagnoser<Ts...> Diagnoser(DiagID, Args...);
     return RequireCompleteExprType(E, CompleteTypeKind::Default, Diagnoser);
   }
 
   template <typename... Ts>
   bool RequireCompleteSizedExprType(Expr *E, unsigned DiagID,
                                     const Ts &... Args) {
     SizelessTypeDiagnoser<Ts...> Diagnoser(DiagID, Args...);
     return RequireCompleteExprType(E, CompleteTypeKind::Normal, Diagnoser);
   }
 
   bool RequireLiteralType(SourceLocation Loc, QualType T,
                           TypeDiagnoser &Diagnoser);
   bool RequireLiteralType(SourceLocation Loc, QualType T, unsigned DiagID);
 
   template <typename... Ts>
   bool RequireLiteralType(SourceLocation Loc, QualType T, unsigned DiagID,
                           const Ts &...Args) {
     BoundTypeDiagnoser<Ts...> Diagnoser(DiagID, Args...);
     return RequireLiteralType(Loc, T, Diagnoser);
   }
 
   QualType getElaboratedType(ElaboratedTypeKeyword Keyword,
                              const CXXScopeSpec &SS, QualType T,
                              TagDecl *OwnedTagDecl = nullptr);
 
   QualType BuildTypeofExprType(Expr *E, SourceLocation Loc);
   /// If AsUnevaluated is false, E is treated as though it were an evaluated
   /// context, such as when building a type for decltype(auto).
   QualType BuildDecltypeType(Expr *E, SourceLocation Loc,
                              bool AsUnevaluated = true);
   QualType BuildUnaryTransformType(QualType BaseType,
                                    UnaryTransformType::UTTKind UKind,
                                    SourceLocation Loc);
 
   //===--------------------------------------------------------------------===//
   // Symbol table / Decl tracking callbacks: SemaDecl.cpp.
   //
 
   struct SkipBodyInfo {
     SkipBodyInfo()
         : ShouldSkip(false), CheckSameAsPrevious(false), Previous(nullptr),
           New(nullptr) {}
     bool ShouldSkip;
     bool CheckSameAsPrevious;
     NamedDecl *Previous;
     NamedDecl *New;
   };
 
   DeclGroupPtrTy ConvertDeclToDeclGroup(Decl *Ptr, Decl *OwnedType = nullptr);
 
   void DiagnoseUseOfUnimplementedSelectors();
 
   bool isSimpleTypeSpecifier(tok::TokenKind Kind) const;
 
   ParsedType getTypeName(const IdentifierInfo &II, SourceLocation NameLoc,
                          Scope *S, CXXScopeSpec *SS = nullptr,
                          bool isClassName = false, bool HasTrailingDot = false,
                          ParsedType ObjectType = nullptr,
                          bool IsCtorOrDtorName = false,
                          bool WantNontrivialTypeSourceInfo = false,
                          bool IsClassTemplateDeductionContext = true,
                          IdentifierInfo **CorrectedII = nullptr);
   TypeSpecifierType isTagName(IdentifierInfo &II, Scope *S);
   bool isMicrosoftMissingTypename(const CXXScopeSpec *SS, Scope *S);
   void DiagnoseUnknownTypeName(IdentifierInfo *&II,
                                SourceLocation IILoc,
                                Scope *S,
                                CXXScopeSpec *SS,
                                ParsedType &SuggestedType,
                                bool IsTemplateName = false);
 
   /// Attempt to behave like MSVC in situations where lookup of an unqualified
   /// type name has failed in a dependent context. In these situations, we
   /// automatically form a DependentTypeName that will retry lookup in a related
   /// scope during instantiation.
   ParsedType ActOnMSVCUnknownTypeName(const IdentifierInfo &II,
                                       SourceLocation NameLoc,
                                       bool IsTemplateTypeArg);
 
   /// Describes the result of the name lookup and resolution performed
   /// by \c ClassifyName().
   enum NameClassificationKind {
     /// This name is not a type or template in this context, but might be
     /// something else.
     NC_Unknown,
     /// Classification failed; an error has been produced.
     NC_Error,
     /// The name has been typo-corrected to a keyword.
     NC_Keyword,
     /// The name was classified as a type.
     NC_Type,
     /// The name was classified as a specific non-type, non-template
     /// declaration. ActOnNameClassifiedAsNonType should be called to
     /// convert the declaration to an expression.
     NC_NonType,
     /// The name was classified as an ADL-only function name.
     /// ActOnNameClassifiedAsUndeclaredNonType should be called to convert the
     /// result to an expression.
     NC_UndeclaredNonType,
     /// The name denotes a member of a dependent type that could not be
     /// resolved. ActOnNameClassifiedAsDependentNonType should be called to
     /// convert the result to an expression.
     NC_DependentNonType,
     /// The name was classified as a non-type, and an expression representing
     /// that name has been formed.
     NC_ContextIndependentExpr,
     /// The name was classified as a template whose specializations are types.
     NC_TypeTemplate,
     /// The name was classified as a variable template name.
     NC_VarTemplate,
     /// The name was classified as a function template name.
     NC_FunctionTemplate,
     /// The name was classified as an ADL-only function template name.
     NC_UndeclaredTemplate,
     /// The name was classified as a concept name.
     NC_Concept,
   };
 
   class NameClassification {
     NameClassificationKind Kind;
     union {
       ExprResult Expr;
       NamedDecl *NonTypeDecl;
       TemplateName Template;
       ParsedType Type;
     };
 
     explicit NameClassification(NameClassificationKind Kind) : Kind(Kind) {}
 
   public:
     NameClassification(ParsedType Type) : Kind(NC_Type), Type(Type) {}
 
     NameClassification(const IdentifierInfo *Keyword) : Kind(NC_Keyword) {}
 
     static NameClassification Error() {
       return NameClassification(NC_Error);
     }
 
     static NameClassification Unknown() {
       return NameClassification(NC_Unknown);
     }
 
     static NameClassification ContextIndependentExpr(ExprResult E) {
       NameClassification Result(NC_ContextIndependentExpr);
       Result.Expr = E;
       return Result;
     }
 
     static NameClassification NonType(NamedDecl *D) {
       NameClassification Result(NC_NonType);
       Result.NonTypeDecl = D;
       return Result;
     }
 
     static NameClassification UndeclaredNonType() {
       return NameClassification(NC_UndeclaredNonType);
     }
 
     static NameClassification DependentNonType() {
       return NameClassification(NC_DependentNonType);
     }
 
     static NameClassification TypeTemplate(TemplateName Name) {
       NameClassification Result(NC_TypeTemplate);
       Result.Template = Name;
       return Result;
     }
 
     static NameClassification VarTemplate(TemplateName Name) {
       NameClassification Result(NC_VarTemplate);
       Result.Template = Name;
       return Result;
     }
 
     static NameClassification FunctionTemplate(TemplateName Name) {
       NameClassification Result(NC_FunctionTemplate);
       Result.Template = Name;
       return Result;
     }
 
     static NameClassification Concept(TemplateName Name) {
       NameClassification Result(NC_Concept);
       Result.Template = Name;
       return Result;
     }
 
     static NameClassification UndeclaredTemplate(TemplateName Name) {
       NameClassification Result(NC_UndeclaredTemplate);
       Result.Template = Name;
       return Result;
     }
 
     NameClassificationKind getKind() const { return Kind; }
 
     ExprResult getExpression() const {
       assert(Kind == NC_ContextIndependentExpr);
       return Expr;
     }
 
     ParsedType getType() const {
       assert(Kind == NC_Type);
       return Type;
     }
 
     NamedDecl *getNonTypeDecl() const {
       assert(Kind == NC_NonType);
       return NonTypeDecl;
     }
 
     TemplateName getTemplateName() const {
       assert(Kind == NC_TypeTemplate || Kind == NC_FunctionTemplate ||
              Kind == NC_VarTemplate || Kind == NC_Concept ||
              Kind == NC_UndeclaredTemplate);
       return Template;
     }
 
     TemplateNameKind getTemplateNameKind() const {
       switch (Kind) {
       case NC_TypeTemplate:
         return TNK_Type_template;
       case NC_FunctionTemplate:
         return TNK_Function_template;
       case NC_VarTemplate:
         return TNK_Var_template;
       case NC_Concept:
         return TNK_Concept_template;
       case NC_UndeclaredTemplate:
         return TNK_Undeclared_template;
       default:
         llvm_unreachable("unsupported name classification.");
       }
     }
   };
 
   /// Perform name lookup on the given name, classifying it based on
   /// the results of name lookup and the following token.
   ///
   /// This routine is used by the parser to resolve identifiers and help direct
   /// parsing. When the identifier cannot be found, this routine will attempt
   /// to correct the typo and classify based on the resulting name.
   ///
   /// \param S The scope in which we're performing name lookup.
   ///
   /// \param SS The nested-name-specifier that precedes the name.
   ///
   /// \param Name The identifier. If typo correction finds an alternative name,
   /// this pointer parameter will be updated accordingly.
   ///
   /// \param NameLoc The location of the identifier.
   ///
   /// \param NextToken The token following the identifier. Used to help
   /// disambiguate the name.
   ///
   /// \param CCC The correction callback, if typo correction is desired.
   NameClassification ClassifyName(Scope *S, CXXScopeSpec &SS,
                                   IdentifierInfo *&Name, SourceLocation NameLoc,
                                   const Token &NextToken,
                                   CorrectionCandidateCallback *CCC = nullptr);
 
   /// Act on the result of classifying a name as an undeclared (ADL-only)
   /// non-type declaration.
   ExprResult ActOnNameClassifiedAsUndeclaredNonType(IdentifierInfo *Name,
                                                     SourceLocation NameLoc);
   /// Act on the result of classifying a name as an undeclared member of a
   /// dependent base class.
   ExprResult ActOnNameClassifiedAsDependentNonType(const CXXScopeSpec &SS,
                                                    IdentifierInfo *Name,
                                                    SourceLocation NameLoc,
                                                    bool IsAddressOfOperand);
   /// Act on the result of classifying a name as a specific non-type
   /// declaration.
   ExprResult ActOnNameClassifiedAsNonType(Scope *S, const CXXScopeSpec &SS,
                                           NamedDecl *Found,
                                           SourceLocation NameLoc,
                                           const Token &NextToken);
 
   /// Describes the detailed kind of a template name. Used in diagnostics.
   enum class TemplateNameKindForDiagnostics {
     ClassTemplate,
     FunctionTemplate,
     VarTemplate,
     AliasTemplate,
     TemplateTemplateParam,
     Concept,
     DependentTemplate
   };
   TemplateNameKindForDiagnostics
   getTemplateNameKindForDiagnostics(TemplateName Name);
 
   /// Determine whether it's plausible that E was intended to be a
   /// template-name.
   bool mightBeIntendedToBeTemplateName(ExprResult E, bool &Dependent) {
     if (!getLangOpts().CPlusPlus || E.isInvalid())
       return false;
     Dependent = false;
     if (auto *DRE = dyn_cast<DeclRefExpr>(E.get()))
       return !DRE->hasExplicitTemplateArgs();
     if (auto *ME = dyn_cast<MemberExpr>(E.get()))
       return !ME->hasExplicitTemplateArgs();
     Dependent = true;
     if (auto *DSDRE = dyn_cast<DependentScopeDeclRefExpr>(E.get()))
       return !DSDRE->hasExplicitTemplateArgs();
     if (auto *DSME = dyn_cast<CXXDependentScopeMemberExpr>(E.get()))
       return !DSME->hasExplicitTemplateArgs();
     // Any additional cases recognized here should also be handled by
     // diagnoseExprIntendedAsTemplateName.
     return false;
   }
   void diagnoseExprIntendedAsTemplateName(Scope *S, ExprResult TemplateName,
                                           SourceLocation Less,
                                           SourceLocation Greater);
 
   Decl *ActOnDeclarator(Scope *S, Declarator &D);
 
   NamedDecl *HandleDeclarator(Scope *S, Declarator &D,
                               MultiTemplateParamsArg TemplateParameterLists);
   void RegisterLocallyScopedExternCDecl(NamedDecl *ND, Scope *S);
   bool DiagnoseClassNameShadow(DeclContext *DC, DeclarationNameInfo Info);
   bool diagnoseQualifiedDeclaration(CXXScopeSpec &SS, DeclContext *DC,
                                     DeclarationName Name, SourceLocation Loc,
                                     bool IsTemplateId);
   void
   diagnoseIgnoredQualifiers(unsigned DiagID, unsigned Quals,
                             SourceLocation FallbackLoc,
                             SourceLocation ConstQualLoc = SourceLocation(),
                             SourceLocation VolatileQualLoc = SourceLocation(),
                             SourceLocation RestrictQualLoc = SourceLocation(),
                             SourceLocation AtomicQualLoc = SourceLocation(),
                             SourceLocation UnalignedQualLoc = SourceLocation());
 
   static bool adjustContextForLocalExternDecl(DeclContext *&DC);
   void DiagnoseFunctionSpecifiers(const DeclSpec &DS);
   NamedDecl *getShadowedDeclaration(const TypedefNameDecl *D,
                                     const LookupResult &R);
   NamedDecl *getShadowedDeclaration(const VarDecl *D, const LookupResult &R);
   void CheckShadow(NamedDecl *D, NamedDecl *ShadowedDecl,
                    const LookupResult &R);
   void CheckShadow(Scope *S, VarDecl *D);
 
   /// Warn if 'E', which is an expression that is about to be modified, refers
   /// to a shadowing declaration.
   void CheckShadowingDeclModification(Expr *E, SourceLocation Loc);
 
   void DiagnoseShadowingLambdaDecls(const sema::LambdaScopeInfo *LSI);
 
 private:
   /// Map of current shadowing declarations to shadowed declarations. Warn if
   /// it looks like the user is trying to modify the shadowing declaration.
   llvm::DenseMap<const NamedDecl *, const NamedDecl *> ShadowingDecls;
 
 public:
   void CheckCastAlign(Expr *Op, QualType T, SourceRange TRange);
   void handleTagNumbering(const TagDecl *Tag, Scope *TagScope);
   void setTagNameForLinkagePurposes(TagDecl *TagFromDeclSpec,
                                     TypedefNameDecl *NewTD);
   void CheckTypedefForVariablyModifiedType(Scope *S, TypedefNameDecl *D);
   NamedDecl* ActOnTypedefDeclarator(Scope* S, Declarator& D, DeclContext* DC,
                                     TypeSourceInfo *TInfo,
                                     LookupResult &Previous);
   NamedDecl* ActOnTypedefNameDecl(Scope* S, DeclContext* DC, TypedefNameDecl *D,
                                   LookupResult &Previous, bool &Redeclaration);
   NamedDecl *ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC,
                                      TypeSourceInfo *TInfo,
                                      LookupResult &Previous,
                                      MultiTemplateParamsArg TemplateParamLists,
                                      bool &AddToScope,
                                      ArrayRef<BindingDecl *> Bindings = None);
   NamedDecl *
   ActOnDecompositionDeclarator(Scope *S, Declarator &D,
                                MultiTemplateParamsArg TemplateParamLists);
   // Returns true if the variable declaration is a redeclaration
   bool CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous);
   void CheckVariableDeclarationType(VarDecl *NewVD);
   bool DeduceVariableDeclarationType(VarDecl *VDecl, bool DirectInit,
                                      Expr *Init);
   void CheckCompleteVariableDeclaration(VarDecl *VD);
   void CheckCompleteDecompositionDeclaration(DecompositionDecl *DD);
   void MaybeSuggestAddingStaticToDecl(const FunctionDecl *D);
 
   NamedDecl* ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC,
                                      TypeSourceInfo *TInfo,
                                      LookupResult &Previous,
                                      MultiTemplateParamsArg TemplateParamLists,
                                      bool &AddToScope);
   bool AddOverriddenMethods(CXXRecordDecl *DC, CXXMethodDecl *MD);
 
   enum class CheckConstexprKind {
     /// Diagnose issues that are non-constant or that are extensions.
     Diagnose,
     /// Identify whether this function satisfies the formal rules for constexpr
     /// functions in the current lanugage mode (with no extensions).
     CheckValid
   };
 
   bool CheckConstexprFunctionDefinition(const FunctionDecl *FD,
                                         CheckConstexprKind Kind);
 
   void DiagnoseHiddenVirtualMethods(CXXMethodDecl *MD);
   void FindHiddenVirtualMethods(CXXMethodDecl *MD,
                           SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods);
   void NoteHiddenVirtualMethods(CXXMethodDecl *MD,
                           SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods);
   // Returns true if the function declaration is a redeclaration
   bool CheckFunctionDeclaration(Scope *S,
                                 FunctionDecl *NewFD, LookupResult &Previous,
                                 bool IsMemberSpecialization);
   bool shouldLinkDependentDeclWithPrevious(Decl *D, Decl *OldDecl);
   bool canFullyTypeCheckRedeclaration(ValueDecl *NewD, ValueDecl *OldD,
                                       QualType NewT, QualType OldT);
   void CheckMain(FunctionDecl *FD, const DeclSpec &D);
   void CheckMSVCRTEntryPoint(FunctionDecl *FD);
   Attr *getImplicitCodeSegOrSectionAttrForFunction(const FunctionDecl *FD,
                                                    bool IsDefinition);
   void CheckFunctionOrTemplateParamDeclarator(Scope *S, Declarator &D);
   Decl *ActOnParamDeclarator(Scope *S, Declarator &D);
   ParmVarDecl *BuildParmVarDeclForTypedef(DeclContext *DC,
                                           SourceLocation Loc,
                                           QualType T);
   ParmVarDecl *CheckParameter(DeclContext *DC, SourceLocation StartLoc,
                               SourceLocation NameLoc, IdentifierInfo *Name,
                               QualType T, TypeSourceInfo *TSInfo,
                               StorageClass SC);
   void ActOnParamDefaultArgument(Decl *param,
                                  SourceLocation EqualLoc,
                                  Expr *defarg);
   void ActOnParamUnparsedDefaultArgument(Decl *param,
                                          SourceLocation EqualLoc,
                                          SourceLocation ArgLoc);
   void ActOnParamDefaultArgumentError(Decl *param, SourceLocation EqualLoc);
   bool SetParamDefaultArgument(ParmVarDecl *Param, Expr *DefaultArg,
                                SourceLocation EqualLoc);
 
   // Contexts where using non-trivial C union types can be disallowed. This is
   // passed to err_non_trivial_c_union_in_invalid_context.
   enum NonTrivialCUnionContext {
     // Function parameter.
     NTCUC_FunctionParam,
     // Function return.
     NTCUC_FunctionReturn,
     // Default-initialized object.
     NTCUC_DefaultInitializedObject,
     // Variable with automatic storage duration.
     NTCUC_AutoVar,
     // Initializer expression that might copy from another object.
     NTCUC_CopyInit,
     // Assignment.
     NTCUC_Assignment,
     // Compound literal.
     NTCUC_CompoundLiteral,
     // Block capture.
     NTCUC_BlockCapture,
     // lvalue-to-rvalue conversion of volatile type.
     NTCUC_LValueToRValueVolatile,
   };
 
   /// Emit diagnostics if the initializer or any of its explicit or
   /// implicitly-generated subexpressions require copying or
   /// default-initializing a type that is or contains a C union type that is
   /// non-trivial to copy or default-initialize.
   void checkNonTrivialCUnionInInitializer(const Expr *Init, SourceLocation Loc);
 
   // These flags are passed to checkNonTrivialCUnion.
   enum NonTrivialCUnionKind {
     NTCUK_Init = 0x1,
     NTCUK_Destruct = 0x2,
     NTCUK_Copy = 0x4,
   };
 
   /// Emit diagnostics if a non-trivial C union type or a struct that contains
   /// a non-trivial C union is used in an invalid context.
   void checkNonTrivialCUnion(QualType QT, SourceLocation Loc,
                              NonTrivialCUnionContext UseContext,
                              unsigned NonTrivialKind);
 
   void AddInitializerToDecl(Decl *dcl, Expr *init, bool DirectInit);
   void ActOnUninitializedDecl(Decl *dcl);
   void ActOnInitializerError(Decl *Dcl);
 
   void ActOnPureSpecifier(Decl *D, SourceLocation PureSpecLoc);
   void ActOnCXXForRangeDecl(Decl *D);
   StmtResult ActOnCXXForRangeIdentifier(Scope *S, SourceLocation IdentLoc,
                                         IdentifierInfo *Ident,
                                         ParsedAttributes &Attrs,
                                         SourceLocation AttrEnd);
   void SetDeclDeleted(Decl *dcl, SourceLocation DelLoc);
   void SetDeclDefaulted(Decl *dcl, SourceLocation DefaultLoc);
   void CheckStaticLocalForDllExport(VarDecl *VD);
   void FinalizeDeclaration(Decl *D);
   DeclGroupPtrTy FinalizeDeclaratorGroup(Scope *S, const DeclSpec &DS,
                                          ArrayRef<Decl *> Group);
   DeclGroupPtrTy BuildDeclaratorGroup(MutableArrayRef<Decl *> Group);
 
   /// Should be called on all declarations that might have attached
   /// documentation comments.
   void ActOnDocumentableDecl(Decl *D);
   void ActOnDocumentableDecls(ArrayRef<Decl *> Group);
 
   void ActOnFinishKNRParamDeclarations(Scope *S, Declarator &D,
                                        SourceLocation LocAfterDecls);
   void CheckForFunctionRedefinition(
       FunctionDecl *FD, const FunctionDecl *EffectiveDefinition = nullptr,
       SkipBodyInfo *SkipBody = nullptr);
   Decl *ActOnStartOfFunctionDef(Scope *S, Declarator &D,
                                 MultiTemplateParamsArg TemplateParamLists,
                                 SkipBodyInfo *SkipBody = nullptr);
   Decl *ActOnStartOfFunctionDef(Scope *S, Decl *D,
                                 SkipBodyInfo *SkipBody = nullptr);
   void ActOnStartTrailingRequiresClause(Scope *S, Declarator &D);
   ExprResult ActOnFinishTrailingRequiresClause(ExprResult ConstraintExpr);
   void ActOnStartOfObjCMethodDef(Scope *S, Decl *D);
   bool isObjCMethodDecl(Decl *D) {
     return D && isa<ObjCMethodDecl>(D);
   }
 
   /// Determine whether we can delay parsing the body of a function or
   /// function template until it is used, assuming we don't care about emitting
   /// code for that function.
   ///
   /// This will be \c false if we may need the body of the function in the
   /// middle of parsing an expression (where it's impractical to switch to
   /// parsing a different function), for instance, if it's constexpr in C++11
   /// or has an 'auto' return type in C++14. These cases are essentially bugs.
   bool canDelayFunctionBody(const Declarator &D);
 
   /// Determine whether we can skip parsing the body of a function
   /// definition, assuming we don't care about analyzing its body or emitting
   /// code for that function.
   ///
   /// This will be \c false only if we may need the body of the function in
   /// order to parse the rest of the program (for instance, if it is
   /// \c constexpr in C++11 or has an 'auto' return type in C++14).
   bool canSkipFunctionBody(Decl *D);
 
   void computeNRVO(Stmt *Body, sema::FunctionScopeInfo *Scope);
   Decl *ActOnFinishFunctionBody(Decl *Decl, Stmt *Body);
   Decl *ActOnFinishFunctionBody(Decl *Decl, Stmt *Body, bool IsInstantiation);
   Decl *ActOnSkippedFunctionBody(Decl *Decl);
   void ActOnFinishInlineFunctionDef(FunctionDecl *D);
 
   /// ActOnFinishDelayedAttribute - Invoked when we have finished parsing an
   /// attribute for which parsing is delayed.
   void ActOnFinishDelayedAttribute(Scope *S, Decl *D, ParsedAttributes &Attrs);
 
   /// Diagnose any unused parameters in the given sequence of
   /// ParmVarDecl pointers.
   void DiagnoseUnusedParameters(ArrayRef<ParmVarDecl *> Parameters);
 
   /// Diagnose whether the size of parameters or return value of a
   /// function or obj-c method definition is pass-by-value and larger than a
   /// specified threshold.
   void
   DiagnoseSizeOfParametersAndReturnValue(ArrayRef<ParmVarDecl *> Parameters,
                                          QualType ReturnTy, NamedDecl *D);
 
   void DiagnoseInvalidJumps(Stmt *Body);
   Decl *ActOnFileScopeAsmDecl(Expr *expr,
                               SourceLocation AsmLoc,
                               SourceLocation RParenLoc);
 
   /// Handle a C++11 empty-declaration and attribute-declaration.
   Decl *ActOnEmptyDeclaration(Scope *S, const ParsedAttributesView &AttrList,
                               SourceLocation SemiLoc);
 
   enum class ModuleDeclKind {
     Interface,      ///< 'export module X;'
     Implementation, ///< 'module X;'
   };
 
   /// The parser has processed a module-declaration that begins the definition
   /// of a module interface or implementation.
   DeclGroupPtrTy ActOnModuleDecl(SourceLocation StartLoc,
                                  SourceLocation ModuleLoc, ModuleDeclKind MDK,
                                  ModuleIdPath Path, bool IsFirstDecl);
 
   /// The parser has processed a global-module-fragment declaration that begins
   /// the definition of the global module fragment of the current module unit.
   /// \param ModuleLoc The location of the 'module' keyword.
   DeclGroupPtrTy ActOnGlobalModuleFragmentDecl(SourceLocation ModuleLoc);
 
   /// The parser has processed a private-module-fragment declaration that begins
   /// the definition of the private module fragment of the current module unit.
   /// \param ModuleLoc The location of the 'module' keyword.
   /// \param PrivateLoc The location of the 'private' keyword.
   DeclGroupPtrTy ActOnPrivateModuleFragmentDecl(SourceLocation ModuleLoc,
                                                 SourceLocation PrivateLoc);
 
   /// The parser has processed a module import declaration.
   ///
   /// \param StartLoc The location of the first token in the declaration. This
   ///        could be the location of an '@', 'export', or 'import'.
   /// \param ExportLoc The location of the 'export' keyword, if any.
   /// \param ImportLoc The location of the 'import' keyword.
   /// \param Path The module access path.
   DeclResult ActOnModuleImport(SourceLocation StartLoc,
                                SourceLocation ExportLoc,
                                SourceLocation ImportLoc, ModuleIdPath Path);
   DeclResult ActOnModuleImport(SourceLocation StartLoc,
                                SourceLocation ExportLoc,
                                SourceLocation ImportLoc, Module *M,
                                ModuleIdPath Path = {});
 
   /// The parser has processed a module import translated from a
   /// #include or similar preprocessing directive.
   void ActOnModuleInclude(SourceLocation DirectiveLoc, Module *Mod);
   void BuildModuleInclude(SourceLocation DirectiveLoc, Module *Mod);
 
   /// The parsed has entered a submodule.
   void ActOnModuleBegin(SourceLocation DirectiveLoc, Module *Mod);
   /// The parser has left a submodule.
   void ActOnModuleEnd(SourceLocation DirectiveLoc, Module *Mod);
 
   /// Create an implicit import of the given module at the given
   /// source location, for error recovery, if possible.
   ///
   /// This routine is typically used when an entity found by name lookup
   /// is actually hidden within a module that we know about but the user
   /// has forgotten to import.
   void createImplicitModuleImportForErrorRecovery(SourceLocation Loc,
                                                   Module *Mod);
 
   /// Kinds of missing import. Note, the values of these enumerators correspond
   /// to %select values in diagnostics.
   enum class MissingImportKind {
     Declaration,
     Definition,
     DefaultArgument,
     ExplicitSpecialization,
     PartialSpecialization
   };
 
   /// Diagnose that the specified declaration needs to be visible but
   /// isn't, and suggest a module import that would resolve the problem.
   void diagnoseMissingImport(SourceLocation Loc, NamedDecl *Decl,
                              MissingImportKind MIK, bool Recover = true);
   void diagnoseMissingImport(SourceLocation Loc, NamedDecl *Decl,
                              SourceLocation DeclLoc, ArrayRef<Module *> Modules,
                              MissingImportKind MIK, bool Recover);
 
   Decl *ActOnStartExportDecl(Scope *S, SourceLocation ExportLoc,
                              SourceLocation LBraceLoc);
   Decl *ActOnFinishExportDecl(Scope *S, Decl *ExportDecl,
                               SourceLocation RBraceLoc);
 
   /// We've found a use of a templated declaration that would trigger an
   /// implicit instantiation. Check that any relevant explicit specializations
   /// and partial specializations are visible, and diagnose if not.
   void checkSpecializationVisibility(SourceLocation Loc, NamedDecl *Spec);
 
   /// We've found a use of a template specialization that would select a
   /// partial specialization. Check that the partial specialization is visible,
   /// and diagnose if not.
   void checkPartialSpecializationVisibility(SourceLocation Loc,
                                             NamedDecl *Spec);
 
   /// Retrieve a suitable printing policy for diagnostics.
   PrintingPolicy getPrintingPolicy() const {
     return getPrintingPolicy(Context, PP);
   }
 
   /// Retrieve a suitable printing policy for diagnostics.
   static PrintingPolicy getPrintingPolicy(const ASTContext &Ctx,
                                           const Preprocessor &PP);
 
   /// Scope actions.
   void ActOnPopScope(SourceLocation Loc, Scope *S);
   void ActOnTranslationUnitScope(Scope *S);
 
   Decl *ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
                                    RecordDecl *&AnonRecord);
   Decl *ParsedFreeStandingDeclSpec(Scope *S, AccessSpecifier AS, DeclSpec &DS,
                                    MultiTemplateParamsArg TemplateParams,
                                    bool IsExplicitInstantiation,
                                    RecordDecl *&AnonRecord);
 
   Decl *BuildAnonymousStructOrUnion(Scope *S, DeclSpec &DS,
                                     AccessSpecifier AS,
                                     RecordDecl *Record,
                                     const PrintingPolicy &Policy);
 
   Decl *BuildMicrosoftCAnonymousStruct(Scope *S, DeclSpec &DS,
                                        RecordDecl *Record);
 
   /// Common ways to introduce type names without a tag for use in diagnostics.
   /// Keep in sync with err_tag_reference_non_tag.
   enum NonTagKind {
     NTK_NonStruct,
     NTK_NonClass,
     NTK_NonUnion,
     NTK_NonEnum,
     NTK_Typedef,
     NTK_TypeAlias,
     NTK_Template,
     NTK_TypeAliasTemplate,
     NTK_TemplateTemplateArgument,
   };
 
   /// Given a non-tag type declaration, returns an enum useful for indicating
   /// what kind of non-tag type this is.
   NonTagKind getNonTagTypeDeclKind(const Decl *D, TagTypeKind TTK);
 
   bool isAcceptableTagRedeclaration(const TagDecl *Previous,
                                     TagTypeKind NewTag, bool isDefinition,
                                     SourceLocation NewTagLoc,
                                     const IdentifierInfo *Name);
 
   enum TagUseKind {
     TUK_Reference,   // Reference to a tag:  'struct foo *X;'
     TUK_Declaration, // Fwd decl of a tag:   'struct foo;'
     TUK_Definition,  // Definition of a tag: 'struct foo { int X; } Y;'
     TUK_Friend       // Friend declaration:  'friend struct foo;'
   };
 
   Decl *ActOnTag(Scope *S, unsigned TagSpec, TagUseKind TUK,
                  SourceLocation KWLoc, CXXScopeSpec &SS, IdentifierInfo *Name,
                  SourceLocation NameLoc, const ParsedAttributesView &Attr,
                  AccessSpecifier AS, SourceLocation ModulePrivateLoc,
                  MultiTemplateParamsArg TemplateParameterLists, bool &OwnedDecl,
                  bool &IsDependent, SourceLocation ScopedEnumKWLoc,
                  bool ScopedEnumUsesClassTag, TypeResult UnderlyingType,
                  bool IsTypeSpecifier, bool IsTemplateParamOrArg,
                  SkipBodyInfo *SkipBody = nullptr);
 
   Decl *ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
                                 unsigned TagSpec, SourceLocation TagLoc,
                                 CXXScopeSpec &SS, IdentifierInfo *Name,
                                 SourceLocation NameLoc,
                                 const ParsedAttributesView &Attr,
                                 MultiTemplateParamsArg TempParamLists);
 
   TypeResult ActOnDependentTag(Scope *S,
                                unsigned TagSpec,
                                TagUseKind TUK,
                                const CXXScopeSpec &SS,
                                IdentifierInfo *Name,
                                SourceLocation TagLoc,
                                SourceLocation NameLoc);
 
   void ActOnDefs(Scope *S, Decl *TagD, SourceLocation DeclStart,
                  IdentifierInfo *ClassName,
                  SmallVectorImpl<Decl *> &Decls);
   Decl *ActOnField(Scope *S, Decl *TagD, SourceLocation DeclStart,
                    Declarator &D, Expr *BitfieldWidth);
 
   FieldDecl *HandleField(Scope *S, RecordDecl *TagD, SourceLocation DeclStart,
                          Declarator &D, Expr *BitfieldWidth,
                          InClassInitStyle InitStyle,
                          AccessSpecifier AS);
   MSPropertyDecl *HandleMSProperty(Scope *S, RecordDecl *TagD,
                                    SourceLocation DeclStart, Declarator &D,
                                    Expr *BitfieldWidth,
                                    InClassInitStyle InitStyle,
                                    AccessSpecifier AS,
                                    const ParsedAttr &MSPropertyAttr);
 
   FieldDecl *CheckFieldDecl(DeclarationName Name, QualType T,
                             TypeSourceInfo *TInfo,
                             RecordDecl *Record, SourceLocation Loc,
                             bool Mutable, Expr *BitfieldWidth,
                             InClassInitStyle InitStyle,
                             SourceLocation TSSL,
                             AccessSpecifier AS, NamedDecl *PrevDecl,
                             Declarator *D = nullptr);
 
   bool CheckNontrivialField(FieldDecl *FD);
   void DiagnoseNontrivial(const CXXRecordDecl *Record, CXXSpecialMember CSM);
 
   enum TrivialABIHandling {
     /// The triviality of a method unaffected by "trivial_abi".
     TAH_IgnoreTrivialABI,
 
     /// The triviality of a method affected by "trivial_abi".
     TAH_ConsiderTrivialABI
   };
 
   bool SpecialMemberIsTrivial(CXXMethodDecl *MD, CXXSpecialMember CSM,
                               TrivialABIHandling TAH = TAH_IgnoreTrivialABI,
                               bool Diagnose = false);
 
   /// For a defaulted function, the kind of defaulted function that it is.
   class DefaultedFunctionKind {
     CXXSpecialMember SpecialMember : 8;
     DefaultedComparisonKind Comparison : 8;
 
   public:
     DefaultedFunctionKind()
         : SpecialMember(CXXInvalid), Comparison(DefaultedComparisonKind::None) {
     }
     DefaultedFunctionKind(CXXSpecialMember CSM)
         : SpecialMember(CSM), Comparison(DefaultedComparisonKind::None) {}
     DefaultedFunctionKind(DefaultedComparisonKind Comp)
         : SpecialMember(CXXInvalid), Comparison(Comp) {}
 
     bool isSpecialMember() const { return SpecialMember != CXXInvalid; }
     bool isComparison() const {
       return Comparison != DefaultedComparisonKind::None;
     }
 
     explicit operator bool() const {
       return isSpecialMember() || isComparison();
     }
 
     CXXSpecialMember asSpecialMember() const { return SpecialMember; }
     DefaultedComparisonKind asComparison() const { return Comparison; }
 
     /// Get the index of this function kind for use in diagnostics.
     unsigned getDiagnosticIndex() const {
       static_assert(CXXInvalid > CXXDestructor,
                     "invalid should have highest index");
       static_assert((unsigned)DefaultedComparisonKind::None == 0,
                     "none should be equal to zero");
       return SpecialMember + (unsigned)Comparison;
     }
   };
 
   DefaultedFunctionKind getDefaultedFunctionKind(const FunctionDecl *FD);
 
   CXXSpecialMember getSpecialMember(const CXXMethodDecl *MD) {
     return getDefaultedFunctionKind(MD).asSpecialMember();
   }
   DefaultedComparisonKind getDefaultedComparisonKind(const FunctionDecl *FD) {
     return getDefaultedFunctionKind(FD).asComparison();
   }
 
   void ActOnLastBitfield(SourceLocation DeclStart,
                          SmallVectorImpl<Decl *> &AllIvarDecls);
   Decl *ActOnIvar(Scope *S, SourceLocation DeclStart,
                   Declarator &D, Expr *BitfieldWidth,
                   tok::ObjCKeywordKind visibility);
 
   // This is used for both record definitions and ObjC interface declarations.
   void ActOnFields(Scope *S, SourceLocation RecLoc, Decl *TagDecl,
                    ArrayRef<Decl *> Fields, SourceLocation LBrac,
                    SourceLocation RBrac, const ParsedAttributesView &AttrList);
 
   /// ActOnTagStartDefinition - Invoked when we have entered the
   /// scope of a tag's definition (e.g., for an enumeration, class,
   /// struct, or union).
   void ActOnTagStartDefinition(Scope *S, Decl *TagDecl);
 
   /// Perform ODR-like check for C/ObjC when merging tag types from modules.
   /// Differently from C++, actually parse the body and reject / error out
   /// in case of a structural mismatch.
   bool ActOnDuplicateDefinition(DeclSpec &DS, Decl *Prev,
                                 SkipBodyInfo &SkipBody);
 
   typedef void *SkippedDefinitionContext;
 
   /// Invoked when we enter a tag definition that we're skipping.
   SkippedDefinitionContext ActOnTagStartSkippedDefinition(Scope *S, Decl *TD);
 
   Decl *ActOnObjCContainerStartDefinition(Decl *IDecl);
 
   /// ActOnStartCXXMemberDeclarations - Invoked when we have parsed a
   /// C++ record definition's base-specifiers clause and are starting its
   /// member declarations.
   void ActOnStartCXXMemberDeclarations(Scope *S, Decl *TagDecl,
                                        SourceLocation FinalLoc,
                                        bool IsFinalSpelledSealed,
                                        SourceLocation LBraceLoc);
 
   /// ActOnTagFinishDefinition - Invoked once we have finished parsing
   /// the definition of a tag (enumeration, class, struct, or union).
   void ActOnTagFinishDefinition(Scope *S, Decl *TagDecl,
                                 SourceRange BraceRange);
 
   void ActOnTagFinishSkippedDefinition(SkippedDefinitionContext Context);
 
   void ActOnObjCContainerFinishDefinition();
 
   /// Invoked when we must temporarily exit the objective-c container
   /// scope for parsing/looking-up C constructs.
   ///
   /// Must be followed by a call to \see ActOnObjCReenterContainerContext
   void ActOnObjCTemporaryExitContainerContext(DeclContext *DC);
   void ActOnObjCReenterContainerContext(DeclContext *DC);
 
   /// ActOnTagDefinitionError - Invoked when there was an unrecoverable
   /// error parsing the definition of a tag.
   void ActOnTagDefinitionError(Scope *S, Decl *TagDecl);
 
   EnumConstantDecl *CheckEnumConstant(EnumDecl *Enum,
                                       EnumConstantDecl *LastEnumConst,
                                       SourceLocation IdLoc,
                                       IdentifierInfo *Id,
                                       Expr *val);
   bool CheckEnumUnderlyingType(TypeSourceInfo *TI);
   bool CheckEnumRedeclaration(SourceLocation EnumLoc, bool IsScoped,
                               QualType EnumUnderlyingTy, bool IsFixed,
                               const EnumDecl *Prev);
 
   /// Determine whether the body of an anonymous enumeration should be skipped.
   /// \param II The name of the first enumerator.
   SkipBodyInfo shouldSkipAnonEnumBody(Scope *S, IdentifierInfo *II,
                                       SourceLocation IILoc);
 
   Decl *ActOnEnumConstant(Scope *S, Decl *EnumDecl, Decl *LastEnumConstant,
                           SourceLocation IdLoc, IdentifierInfo *Id,
                           const ParsedAttributesView &Attrs,
                           SourceLocation EqualLoc, Expr *Val);
   void ActOnEnumBody(SourceLocation EnumLoc, SourceRange BraceRange,
                      Decl *EnumDecl, ArrayRef<Decl *> Elements, Scope *S,
                      const ParsedAttributesView &Attr);
 
   DeclContext *getContainingDC(DeclContext *DC);
 
   /// Set the current declaration context until it gets popped.
   void PushDeclContext(Scope *S, DeclContext *DC);
   void PopDeclContext();
 
   /// EnterDeclaratorContext - Used when we must lookup names in the context
   /// of a declarator's nested name specifier.
   void EnterDeclaratorContext(Scope *S, DeclContext *DC);
   void ExitDeclaratorContext(Scope *S);
 
   /// Push the parameters of D, which must be a function, into scope.
   void ActOnReenterFunctionContext(Scope* S, Decl* D);
   void ActOnExitFunctionContext();
 
   DeclContext *getFunctionLevelDeclContext();
 
   /// getCurFunctionDecl - If inside of a function body, this returns a pointer
   /// to the function decl for the function being parsed.  If we're currently
   /// in a 'block', this returns the containing context.
   FunctionDecl *getCurFunctionDecl();
 
   /// getCurMethodDecl - If inside of a method body, this returns a pointer to
   /// the method decl for the method being parsed.  If we're currently
   /// in a 'block', this returns the containing context.
   ObjCMethodDecl *getCurMethodDecl();
 
   /// getCurFunctionOrMethodDecl - Return the Decl for the current ObjC method
   /// or C function we're in, otherwise return null.  If we're currently
   /// in a 'block', this returns the containing context.
   NamedDecl *getCurFunctionOrMethodDecl();
 
   /// Add this decl to the scope shadowed decl chains.
   void PushOnScopeChains(NamedDecl *D, Scope *S, bool AddToContext = true);
 
   /// isDeclInScope - If 'Ctx' is a function/method, isDeclInScope returns true
   /// if 'D' is in Scope 'S', otherwise 'S' is ignored and isDeclInScope returns
   /// true if 'D' belongs to the given declaration context.
   ///
   /// \param AllowInlineNamespace If \c true, allow the declaration to be in the
   ///        enclosing namespace set of the context, rather than contained
   ///        directly within it.
   bool isDeclInScope(NamedDecl *D, DeclContext *Ctx, Scope *S = nullptr,
                      bool AllowInlineNamespace = false);
 
   /// Finds the scope corresponding to the given decl context, if it
   /// happens to be an enclosing scope.  Otherwise return NULL.
   static Scope *getScopeForDeclContext(Scope *S, DeclContext *DC);
 
   /// Subroutines of ActOnDeclarator().
   TypedefDecl *ParseTypedefDecl(Scope *S, Declarator &D, QualType T,
                                 TypeSourceInfo *TInfo);
   bool isIncompatibleTypedef(TypeDecl *Old, TypedefNameDecl *New);
 
   /// Describes the kind of merge to perform for availability
   /// attributes (including "deprecated", "unavailable", and "availability").
   enum AvailabilityMergeKind {
     /// Don't merge availability attributes at all.
     AMK_None,
     /// Merge availability attributes for a redeclaration, which requires
     /// an exact match.
     AMK_Redeclaration,
     /// Merge availability attributes for an override, which requires
     /// an exact match or a weakening of constraints.
     AMK_Override,
     /// Merge availability attributes for an implementation of
     /// a protocol requirement.
     AMK_ProtocolImplementation,
   };
 
   /// Describes the kind of priority given to an availability attribute.
   ///
   /// The sum of priorities deteremines the final priority of the attribute.
   /// The final priority determines how the attribute will be merged.
   /// An attribute with a lower priority will always remove higher priority
   /// attributes for the specified platform when it is being applied. An
   /// attribute with a higher priority will not be applied if the declaration
   /// already has an availability attribute with a lower priority for the
   /// specified platform. The final prirority values are not expected to match
   /// the values in this enumeration, but instead should be treated as a plain
   /// integer value. This enumeration just names the priority weights that are
   /// used to calculate that final vaue.
   enum AvailabilityPriority : int {
     /// The availability attribute was specified explicitly next to the
     /// declaration.
     AP_Explicit = 0,
 
     /// The availability attribute was applied using '#pragma clang attribute'.
     AP_PragmaClangAttribute = 1,
 
     /// The availability attribute for a specific platform was inferred from
     /// an availability attribute for another platform.
     AP_InferredFromOtherPlatform = 2
   };
 
   /// Attribute merging methods. Return true if a new attribute was added.
   AvailabilityAttr *
   mergeAvailabilityAttr(NamedDecl *D, const AttributeCommonInfo &CI,
                         IdentifierInfo *Platform, bool Implicit,
                         VersionTuple Introduced, VersionTuple Deprecated,
                         VersionTuple Obsoleted, bool IsUnavailable,
                         StringRef Message, bool IsStrict, StringRef Replacement,
                         AvailabilityMergeKind AMK, int Priority);
   TypeVisibilityAttr *
   mergeTypeVisibilityAttr(Decl *D, const AttributeCommonInfo &CI,
                           TypeVisibilityAttr::VisibilityType Vis);
   VisibilityAttr *mergeVisibilityAttr(Decl *D, const AttributeCommonInfo &CI,
                                       VisibilityAttr::VisibilityType Vis);
   UuidAttr *mergeUuidAttr(Decl *D, const AttributeCommonInfo &CI,
                           StringRef Uuid);
   DLLImportAttr *mergeDLLImportAttr(Decl *D, const AttributeCommonInfo &CI);
   DLLExportAttr *mergeDLLExportAttr(Decl *D, const AttributeCommonInfo &CI);
   MSInheritanceAttr *mergeMSInheritanceAttr(Decl *D,
                                             const AttributeCommonInfo &CI,
                                             bool BestCase,
                                             MSInheritanceModel Model);
   FormatAttr *mergeFormatAttr(Decl *D, const AttributeCommonInfo &CI,
                               IdentifierInfo *Format, int FormatIdx,
                               int FirstArg);
   SectionAttr *mergeSectionAttr(Decl *D, const AttributeCommonInfo &CI,
                                 StringRef Name);
   CodeSegAttr *mergeCodeSegAttr(Decl *D, const AttributeCommonInfo &CI,
                                 StringRef Name);
   AlwaysInlineAttr *mergeAlwaysInlineAttr(Decl *D,
                                           const AttributeCommonInfo &CI,
                                           const IdentifierInfo *Ident);
   MinSizeAttr *mergeMinSizeAttr(Decl *D, const AttributeCommonInfo &CI);
   NoSpeculativeLoadHardeningAttr *
   mergeNoSpeculativeLoadHardeningAttr(Decl *D,
                                       const NoSpeculativeLoadHardeningAttr &AL);
   SpeculativeLoadHardeningAttr *
   mergeSpeculativeLoadHardeningAttr(Decl *D,
                                     const SpeculativeLoadHardeningAttr &AL);
   OptimizeNoneAttr *mergeOptimizeNoneAttr(Decl *D,
                                           const AttributeCommonInfo &CI);
   InternalLinkageAttr *mergeInternalLinkageAttr(Decl *D, const ParsedAttr &AL);
   InternalLinkageAttr *mergeInternalLinkageAttr(Decl *D,
                                                 const InternalLinkageAttr &AL);
   CommonAttr *mergeCommonAttr(Decl *D, const ParsedAttr &AL);
   CommonAttr *mergeCommonAttr(Decl *D, const CommonAttr &AL);
 
   void mergeDeclAttributes(NamedDecl *New, Decl *Old,
                            AvailabilityMergeKind AMK = AMK_Redeclaration);
   void MergeTypedefNameDecl(Scope *S, TypedefNameDecl *New,
                             LookupResult &OldDecls);
   bool MergeFunctionDecl(FunctionDecl *New, NamedDecl *&Old, Scope *S,
                          bool MergeTypeWithOld);
   bool MergeCompatibleFunctionDecls(FunctionDecl *New, FunctionDecl *Old,
                                     Scope *S, bool MergeTypeWithOld);
   void mergeObjCMethodDecls(ObjCMethodDecl *New, ObjCMethodDecl *Old);
   void MergeVarDecl(VarDecl *New, LookupResult &Previous);
   void MergeVarDeclTypes(VarDecl *New, VarDecl *Old, bool MergeTypeWithOld);
   void MergeVarDeclExceptionSpecs(VarDecl *New, VarDecl *Old);
   bool checkVarDeclRedefinition(VarDecl *OldDefn, VarDecl *NewDefn);
   void notePreviousDefinition(const NamedDecl *Old, SourceLocation New);
   bool MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old, Scope *S);
 
   // AssignmentAction - This is used by all the assignment diagnostic functions
   // to represent what is actually causing the operation
   enum AssignmentAction {
     AA_Assigning,
     AA_Passing,
     AA_Returning,
     AA_Converting,
     AA_Initializing,
     AA_Sending,
     AA_Casting,
     AA_Passing_CFAudited
   };
 
   /// C++ Overloading.
   enum OverloadKind {
     /// This is a legitimate overload: the existing declarations are
     /// functions or function templates with different signatures.
     Ovl_Overload,
 
     /// This is not an overload because the signature exactly matches
     /// an existing declaration.
     Ovl_Match,
 
     /// This is not an overload because the lookup results contain a
     /// non-function.
     Ovl_NonFunction
   };
   OverloadKind CheckOverload(Scope *S,
                              FunctionDecl *New,
                              const LookupResult &OldDecls,
                              NamedDecl *&OldDecl,
                              bool IsForUsingDecl);
   bool IsOverload(FunctionDecl *New, FunctionDecl *Old, bool IsForUsingDecl,
                   bool ConsiderCudaAttrs = true,
                   bool ConsiderRequiresClauses = true);
 
   enum class AllowedExplicit {
     /// Allow no explicit functions to be used.
     None,
     /// Allow explicit conversion functions but not explicit constructors.
     Conversions,
     /// Allow both explicit conversion functions and explicit constructors.
     All
   };
 
   ImplicitConversionSequence
   TryImplicitConversion(Expr *From, QualType ToType,
                         bool SuppressUserConversions,
                         AllowedExplicit AllowExplicit,
                         bool InOverloadResolution,
                         bool CStyle,
                         bool AllowObjCWritebackConversion);
 
   bool IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType);
   bool IsFloatingPointPromotion(QualType FromType, QualType ToType);
   bool IsComplexPromotion(QualType FromType, QualType ToType);
   bool IsPointerConversion(Expr *From, QualType FromType, QualType ToType,
                            bool InOverloadResolution,
                            QualType& ConvertedType, bool &IncompatibleObjC);
   bool isObjCPointerConversion(QualType FromType, QualType ToType,
                                QualType& ConvertedType, bool &IncompatibleObjC);
   bool isObjCWritebackConversion(QualType FromType, QualType ToType,
                                  QualType &ConvertedType);
   bool IsBlockPointerConversion(QualType FromType, QualType ToType,
                                 QualType& ConvertedType);
   bool FunctionParamTypesAreEqual(const FunctionProtoType *OldType,
                                   const FunctionProtoType *NewType,
                                   unsigned *ArgPos = nullptr);
   void HandleFunctionTypeMismatch(PartialDiagnostic &PDiag,
                                   QualType FromType, QualType ToType);
 
   void maybeExtendBlockObject(ExprResult &E);
   CastKind PrepareCastToObjCObjectPointer(ExprResult &E);
   bool CheckPointerConversion(Expr *From, QualType ToType,
                               CastKind &Kind,
                               CXXCastPath& BasePath,
                               bool IgnoreBaseAccess,
                               bool Diagnose = true);
   bool IsMemberPointerConversion(Expr *From, QualType FromType, QualType ToType,
                                  bool InOverloadResolution,
                                  QualType &ConvertedType);
   bool CheckMemberPointerConversion(Expr *From, QualType ToType,
                                     CastKind &Kind,
                                     CXXCastPath &BasePath,
                                     bool IgnoreBaseAccess);
   bool IsQualificationConversion(QualType FromType, QualType ToType,
                                  bool CStyle, bool &ObjCLifetimeConversion);
   bool IsFunctionConversion(QualType FromType, QualType ToType,
                             QualType &ResultTy);
   bool DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType);
   bool isSameOrCompatibleFunctionType(CanQualType Param, CanQualType Arg);
 
   ExprResult PerformMoveOrCopyInitialization(const InitializedEntity &Entity,
                                              const VarDecl *NRVOCandidate,
                                              QualType ResultType,
                                              Expr *Value,
                                              bool AllowNRVO = true);
 
   bool CanPerformAggregateInitializationForOverloadResolution(
       const InitializedEntity &Entity, InitListExpr *From);
 
   bool CanPerformCopyInitialization(const InitializedEntity &Entity,
                                     ExprResult Init);
   ExprResult PerformCopyInitialization(const InitializedEntity &Entity,
                                        SourceLocation EqualLoc,
                                        ExprResult Init,
                                        bool TopLevelOfInitList = false,
                                        bool AllowExplicit = false);
   ExprResult PerformObjectArgumentInitialization(Expr *From,
                                                  NestedNameSpecifier *Qualifier,
                                                  NamedDecl *FoundDecl,
                                                  CXXMethodDecl *Method);
 
   /// Check that the lifetime of the initializer (and its subobjects) is
   /// sufficient for initializing the entity, and perform lifetime extension
   /// (when permitted) if not.
   void checkInitializerLifetime(const InitializedEntity &Entity, Expr *Init);
 
   ExprResult PerformContextuallyConvertToBool(Expr *From);
   ExprResult PerformContextuallyConvertToObjCPointer(Expr *From);
 
   /// Contexts in which a converted constant expression is required.
   enum CCEKind {
     CCEK_CaseValue,   ///< Expression in a case label.
     CCEK_Enumerator,  ///< Enumerator value with fixed underlying type.
     CCEK_TemplateArg, ///< Value of a non-type template parameter.
     CCEK_NewExpr,     ///< Constant expression in a noptr-new-declarator.
     CCEK_ConstexprIf, ///< Condition in a constexpr if statement.
     CCEK_ExplicitBool ///< Condition in an explicit(bool) specifier.
   };
   ExprResult CheckConvertedConstantExpression(Expr *From, QualType T,
                                               llvm::APSInt &Value, CCEKind CCE);
   ExprResult CheckConvertedConstantExpression(Expr *From, QualType T,
                                               APValue &Value, CCEKind CCE);
 
   /// Abstract base class used to perform a contextual implicit
   /// conversion from an expression to any type passing a filter.
   class ContextualImplicitConverter {
   public:
     bool Suppress;
     bool SuppressConversion;
 
     ContextualImplicitConverter(bool Suppress = false,
                                 bool SuppressConversion = false)
         : Suppress(Suppress), SuppressConversion(SuppressConversion) {}
 
     /// Determine whether the specified type is a valid destination type
     /// for this conversion.
     virtual bool match(QualType T) = 0;
 
     /// Emits a diagnostic complaining that the expression does not have
     /// integral or enumeration type.
     virtual SemaDiagnosticBuilder
     diagnoseNoMatch(Sema &S, SourceLocation Loc, QualType T) = 0;
 
     /// Emits a diagnostic when the expression has incomplete class type.
     virtual SemaDiagnosticBuilder
     diagnoseIncomplete(Sema &S, SourceLocation Loc, QualType T) = 0;
 
     /// Emits a diagnostic when the only matching conversion function
     /// is explicit.
     virtual SemaDiagnosticBuilder diagnoseExplicitConv(
         Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) = 0;
 
     /// Emits a note for the explicit conversion function.
     virtual SemaDiagnosticBuilder
     noteExplicitConv(Sema &S, CXXConversionDecl *Conv, QualType ConvTy) = 0;
 
     /// Emits a diagnostic when there are multiple possible conversion
     /// functions.
     virtual SemaDiagnosticBuilder
     diagnoseAmbiguous(Sema &S, SourceLocation Loc, QualType T) = 0;
 
     /// Emits a note for one of the candidate conversions.
     virtual SemaDiagnosticBuilder
     noteAmbiguous(Sema &S, CXXConversionDecl *Conv, QualType ConvTy) = 0;
 
     /// Emits a diagnostic when we picked a conversion function
     /// (for cases when we are not allowed to pick a conversion function).
     virtual SemaDiagnosticBuilder diagnoseConversion(
         Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) = 0;
 
     virtual ~ContextualImplicitConverter() {}
   };
 
   class ICEConvertDiagnoser : public ContextualImplicitConverter {
     bool AllowScopedEnumerations;
 
   public:
     ICEConvertDiagnoser(bool AllowScopedEnumerations,
                         bool Suppress, bool SuppressConversion)
         : ContextualImplicitConverter(Suppress, SuppressConversion),
           AllowScopedEnumerations(AllowScopedEnumerations) {}
 
     /// Match an integral or (possibly scoped) enumeration type.
     bool match(QualType T) override;
 
     SemaDiagnosticBuilder
     diagnoseNoMatch(Sema &S, SourceLocation Loc, QualType T) override {
       return diagnoseNotInt(S, Loc, T);
     }
 
     /// Emits a diagnostic complaining that the expression does not have
     /// integral or enumeration type.
     virtual SemaDiagnosticBuilder
     diagnoseNotInt(Sema &S, SourceLocation Loc, QualType T) = 0;
   };
 
   /// Perform a contextual implicit conversion.
   ExprResult PerformContextualImplicitConversion(
       SourceLocation Loc, Expr *FromE, ContextualImplicitConverter &Converter);
 
 
   enum ObjCSubscriptKind {
     OS_Array,
     OS_Dictionary,
     OS_Error
   };
   ObjCSubscriptKind CheckSubscriptingKind(Expr *FromE);
 
   // Note that LK_String is intentionally after the other literals, as
   // this is used for diagnostics logic.
   enum ObjCLiteralKind {
     LK_Array,
     LK_Dictionary,
     LK_Numeric,
     LK_Boxed,
     LK_String,
     LK_Block,
     LK_None
   };
   ObjCLiteralKind CheckLiteralKind(Expr *FromE);
 
   ExprResult PerformObjectMemberConversion(Expr *From,
                                            NestedNameSpecifier *Qualifier,
                                            NamedDecl *FoundDecl,
                                            NamedDecl *Member);
 
   // Members have to be NamespaceDecl* or TranslationUnitDecl*.
   // TODO: make this is a typesafe union.
   typedef llvm::SmallSetVector<DeclContext   *, 16> AssociatedNamespaceSet;
   typedef llvm::SmallSetVector<CXXRecordDecl *, 16> AssociatedClassSet;
 
   using ADLCallKind = CallExpr::ADLCallKind;
 
   void AddOverloadCandidate(FunctionDecl *Function, DeclAccessPair FoundDecl,
                             ArrayRef<Expr *> Args,
                             OverloadCandidateSet &CandidateSet,
                             bool SuppressUserConversions = false,
                             bool PartialOverloading = false,
                             bool AllowExplicit = true,
                             bool AllowExplicitConversion = false,
                             ADLCallKind IsADLCandidate = ADLCallKind::NotADL,
                             ConversionSequenceList EarlyConversions = None,
                             OverloadCandidateParamOrder PO = {});
   void AddFunctionCandidates(const UnresolvedSetImpl &Functions,
                       ArrayRef<Expr *> Args,
                       OverloadCandidateSet &CandidateSet,
                       TemplateArgumentListInfo *ExplicitTemplateArgs = nullptr,
                       bool SuppressUserConversions = false,
                       bool PartialOverloading = false,
                       bool FirstArgumentIsBase = false);
   void AddMethodCandidate(DeclAccessPair FoundDecl,
                           QualType ObjectType,
                           Expr::Classification ObjectClassification,
                           ArrayRef<Expr *> Args,
                           OverloadCandidateSet& CandidateSet,
                           bool SuppressUserConversion = false,
                           OverloadCandidateParamOrder PO = {});
   void AddMethodCandidate(CXXMethodDecl *Method,
                           DeclAccessPair FoundDecl,
                           CXXRecordDecl *ActingContext, QualType ObjectType,
                           Expr::Classification ObjectClassification,
                           ArrayRef<Expr *> Args,
                           OverloadCandidateSet& CandidateSet,
                           bool SuppressUserConversions = false,
                           bool PartialOverloading = false,
                           ConversionSequenceList EarlyConversions = None,
                           OverloadCandidateParamOrder PO = {});
   void AddMethodTemplateCandidate(FunctionTemplateDecl *MethodTmpl,
                                   DeclAccessPair FoundDecl,
                                   CXXRecordDecl *ActingContext,
                                  TemplateArgumentListInfo *ExplicitTemplateArgs,
                                   QualType ObjectType,
                                   Expr::Classification ObjectClassification,
                                   ArrayRef<Expr *> Args,
                                   OverloadCandidateSet& CandidateSet,
                                   bool SuppressUserConversions = false,
                                   bool PartialOverloading = false,
                                   OverloadCandidateParamOrder PO = {});
   void AddTemplateOverloadCandidate(
       FunctionTemplateDecl *FunctionTemplate, DeclAccessPair FoundDecl,
       TemplateArgumentListInfo *ExplicitTemplateArgs, ArrayRef<Expr *> Args,
       OverloadCandidateSet &CandidateSet, bool SuppressUserConversions = false,
       bool PartialOverloading = false, bool AllowExplicit = true,
       ADLCallKind IsADLCandidate = ADLCallKind::NotADL,
       OverloadCandidateParamOrder PO = {});
   bool CheckNonDependentConversions(
       FunctionTemplateDecl *FunctionTemplate, ArrayRef<QualType> ParamTypes,
       ArrayRef<Expr *> Args, OverloadCandidateSet &CandidateSet,
       ConversionSequenceList &Conversions, bool SuppressUserConversions,
       CXXRecordDecl *ActingContext = nullptr, QualType ObjectType = QualType(),
       Expr::Classification ObjectClassification = {},
       OverloadCandidateParamOrder PO = {});
   void AddConversionCandidate(
       CXXConversionDecl *Conversion, DeclAccessPair FoundDecl,
       CXXRecordDecl *ActingContext, Expr *From, QualType ToType,
       OverloadCandidateSet &CandidateSet, bool AllowObjCConversionOnExplicit,
       bool AllowExplicit, bool AllowResultConversion = true);
   void AddTemplateConversionCandidate(
       FunctionTemplateDecl *FunctionTemplate, DeclAccessPair FoundDecl,
       CXXRecordDecl *ActingContext, Expr *From, QualType ToType,
       OverloadCandidateSet &CandidateSet, bool AllowObjCConversionOnExplicit,
       bool AllowExplicit, bool AllowResultConversion = true);
   void AddSurrogateCandidate(CXXConversionDecl *Conversion,
                              DeclAccessPair FoundDecl,
                              CXXRecordDecl *ActingContext,
                              const FunctionProtoType *Proto,
                              Expr *Object, ArrayRef<Expr *> Args,
                              OverloadCandidateSet& CandidateSet);
   void AddNonMemberOperatorCandidates(
       const UnresolvedSetImpl &Functions, ArrayRef<Expr *> Args,
       OverloadCandidateSet &CandidateSet,
       TemplateArgumentListInfo *ExplicitTemplateArgs = nullptr);
   void AddMemberOperatorCandidates(OverloadedOperatorKind Op,
                                    SourceLocation OpLoc, ArrayRef<Expr *> Args,
                                    OverloadCandidateSet &CandidateSet,
                                    OverloadCandidateParamOrder PO = {});
   void AddBuiltinCandidate(QualType *ParamTys, ArrayRef<Expr *> Args,
                            OverloadCandidateSet& CandidateSet,
                            bool IsAssignmentOperator = false,
                            unsigned NumContextualBoolArguments = 0);
   void AddBuiltinOperatorCandidates(OverloadedOperatorKind Op,
                                     SourceLocation OpLoc, ArrayRef<Expr *> Args,
                                     OverloadCandidateSet& CandidateSet);
   void AddArgumentDependentLookupCandidates(DeclarationName Name,
                                             SourceLocation Loc,
                                             ArrayRef<Expr *> Args,
                                 TemplateArgumentListInfo *ExplicitTemplateArgs,
                                             OverloadCandidateSet& CandidateSet,
                                             bool PartialOverloading = false);
 
   // Emit as a 'note' the specific overload candidate
   void NoteOverloadCandidate(
       NamedDecl *Found, FunctionDecl *Fn,
       OverloadCandidateRewriteKind RewriteKind = OverloadCandidateRewriteKind(),
       QualType DestType = QualType(), bool TakingAddress = false);
 
   // Emit as a series of 'note's all template and non-templates identified by
   // the expression Expr
   void NoteAllOverloadCandidates(Expr *E, QualType DestType = QualType(),
                                  bool TakingAddress = false);
 
   /// Check the enable_if expressions on the given function. Returns the first
   /// failing attribute, or NULL if they were all successful.
   EnableIfAttr *CheckEnableIf(FunctionDecl *Function, ArrayRef<Expr *> Args,
                               bool MissingImplicitThis = false);
 
   /// Find the failed Boolean condition within a given Boolean
   /// constant expression, and describe it with a string.
   std::pair<Expr *, std::string> findFailedBooleanCondition(Expr *Cond);
 
   /// Emit diagnostics for the diagnose_if attributes on Function, ignoring any
   /// non-ArgDependent DiagnoseIfAttrs.
   ///
   /// Argument-dependent diagnose_if attributes should be checked each time a
   /// function is used as a direct callee of a function call.
   ///
   /// Returns true if any errors were emitted.
   bool diagnoseArgDependentDiagnoseIfAttrs(const FunctionDecl *Function,
                                            const Expr *ThisArg,
                                            ArrayRef<const Expr *> Args,
                                            SourceLocation Loc);
 
   /// Emit diagnostics for the diagnose_if attributes on Function, ignoring any
   /// ArgDependent DiagnoseIfAttrs.
   ///
   /// Argument-independent diagnose_if attributes should be checked on every use
   /// of a function.
   ///
   /// Returns true if any errors were emitted.
   bool diagnoseArgIndependentDiagnoseIfAttrs(const NamedDecl *ND,
                                              SourceLocation Loc);
 
   /// Returns whether the given function's address can be taken or not,
   /// optionally emitting a diagnostic if the address can't be taken.
   ///
   /// Returns false if taking the address of the function is illegal.
   bool checkAddressOfFunctionIsAvailable(const FunctionDecl *Function,
                                          bool Complain = false,
                                          SourceLocation Loc = SourceLocation());
 
   // [PossiblyAFunctionType]  -->   [Return]
   // NonFunctionType --> NonFunctionType
   // R (A) --> R(A)
   // R (*)(A) --> R (A)
   // R (&)(A) --> R (A)
   // R (S::*)(A) --> R (A)
   QualType ExtractUnqualifiedFunctionType(QualType PossiblyAFunctionType);
 
   FunctionDecl *
   ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr,
                                      QualType TargetType,
                                      bool Complain,
                                      DeclAccessPair &Found,
                                      bool *pHadMultipleCandidates = nullptr);
 
   FunctionDecl *
   resolveAddressOfSingleOverloadCandidate(Expr *E, DeclAccessPair &FoundResult);
 
   bool resolveAndFixAddressOfSingleOverloadCandidate(
       ExprResult &SrcExpr, bool DoFunctionPointerConversion = false);
 
   FunctionDecl *
   ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl,
                                               bool Complain = false,
                                               DeclAccessPair *Found = nullptr);
 
   bool ResolveAndFixSingleFunctionTemplateSpecialization(
                       ExprResult &SrcExpr,
                       bool DoFunctionPointerConverion = false,
                       bool Complain = false,
                       SourceRange OpRangeForComplaining = SourceRange(),
                       QualType DestTypeForComplaining = QualType(),
                       unsigned DiagIDForComplaining = 0);
 
 
   Expr *FixOverloadedFunctionReference(Expr *E,
                                        DeclAccessPair FoundDecl,
                                        FunctionDecl *Fn);
   ExprResult FixOverloadedFunctionReference(ExprResult,
                                             DeclAccessPair FoundDecl,
                                             FunctionDecl *Fn);
 
   void AddOverloadedCallCandidates(UnresolvedLookupExpr *ULE,
                                    ArrayRef<Expr *> Args,
                                    OverloadCandidateSet &CandidateSet,
                                    bool PartialOverloading = false);
 
   // An enum used to represent the different possible results of building a
   // range-based for loop.
   enum ForRangeStatus {
     FRS_Success,
     FRS_NoViableFunction,
     FRS_DiagnosticIssued
   };
 
   ForRangeStatus BuildForRangeBeginEndCall(SourceLocation Loc,
                                            SourceLocation RangeLoc,
                                            const DeclarationNameInfo &NameInfo,
                                            LookupResult &MemberLookup,
                                            OverloadCandidateSet *CandidateSet,
                                            Expr *Range, ExprResult *CallExpr);
 
   ExprResult BuildOverloadedCallExpr(Scope *S, Expr *Fn,
                                      UnresolvedLookupExpr *ULE,
                                      SourceLocation LParenLoc,
                                      MultiExprArg Args,
                                      SourceLocation RParenLoc,
                                      Expr *ExecConfig,
                                      bool AllowTypoCorrection=true,
                                      bool CalleesAddressIsTaken=false);
 
   bool buildOverloadedCallSet(Scope *S, Expr *Fn, UnresolvedLookupExpr *ULE,
                               MultiExprArg Args, SourceLocation RParenLoc,
                               OverloadCandidateSet *CandidateSet,
                               ExprResult *Result);
 
   ExprResult CreateOverloadedUnaryOp(SourceLocation OpLoc,
                                      UnaryOperatorKind Opc,
                                      const UnresolvedSetImpl &Fns,
                                      Expr *input, bool RequiresADL = true);
 
   void LookupOverloadedBinOp(OverloadCandidateSet &CandidateSet,
                              OverloadedOperatorKind Op,
                              const UnresolvedSetImpl &Fns,
                              ArrayRef<Expr *> Args, bool RequiresADL = true);
   ExprResult CreateOverloadedBinOp(SourceLocation OpLoc,
                                    BinaryOperatorKind Opc,
                                    const UnresolvedSetImpl &Fns,
                                    Expr *LHS, Expr *RHS,
                                    bool RequiresADL = true,
                                    bool AllowRewrittenCandidates = true,
                                    FunctionDecl *DefaultedFn = nullptr);
   ExprResult BuildSynthesizedThreeWayComparison(SourceLocation OpLoc,
                                                 const UnresolvedSetImpl &Fns,
                                                 Expr *LHS, Expr *RHS,
                                                 FunctionDecl *DefaultedFn);
 
   ExprResult CreateOverloadedArraySubscriptExpr(SourceLocation LLoc,
                                                 SourceLocation RLoc,
                                                 Expr *Base,Expr *Idx);
 
   ExprResult
   BuildCallToMemberFunction(Scope *S, Expr *MemExpr,
                             SourceLocation LParenLoc,
                             MultiExprArg Args,
                             SourceLocation RParenLoc);
   ExprResult
   BuildCallToObjectOfClassType(Scope *S, Expr *Object, SourceLocation LParenLoc,
                                MultiExprArg Args,
                                SourceLocation RParenLoc);
 
   ExprResult BuildOverloadedArrowExpr(Scope *S, Expr *Base,
                                       SourceLocation OpLoc,
                                       bool *NoArrowOperatorFound = nullptr);
 
   /// CheckCallReturnType - Checks that a call expression's return type is
   /// complete. Returns true on failure. The location passed in is the location
   /// that best represents the call.
   bool CheckCallReturnType(QualType ReturnType, SourceLocation Loc,
                            CallExpr *CE, FunctionDecl *FD);
 
   /// Helpers for dealing with blocks and functions.
   bool CheckParmsForFunctionDef(ArrayRef<ParmVarDecl *> Parameters,
                                 bool CheckParameterNames);
   void CheckCXXDefaultArguments(FunctionDecl *FD);
   void CheckExtraCXXDefaultArguments(Declarator &D);
   Scope *getNonFieldDeclScope(Scope *S);
 
   /// \name Name lookup
   ///
   /// These routines provide name lookup that is used during semantic
   /// analysis to resolve the various kinds of names (identifiers,
   /// overloaded operator names, constructor names, etc.) into zero or
   /// more declarations within a particular scope. The major entry
   /// points are LookupName, which performs unqualified name lookup,
   /// and LookupQualifiedName, which performs qualified name lookup.
   ///
   /// All name lookup is performed based on some specific criteria,
   /// which specify what names will be visible to name lookup and how
   /// far name lookup should work. These criteria are important both
   /// for capturing language semantics (certain lookups will ignore
   /// certain names, for example) and for performance, since name
   /// lookup is often a bottleneck in the compilation of C++. Name
   /// lookup criteria is specified via the LookupCriteria enumeration.
   ///
   /// The results of name lookup can vary based on the kind of name
   /// lookup performed, the current language, and the translation
   /// unit. In C, for example, name lookup will either return nothing
   /// (no entity found) or a single declaration. In C++, name lookup
   /// can additionally refer to a set of overloaded functions or
   /// result in an ambiguity. All of the possible results of name
   /// lookup are captured by the LookupResult class, which provides
   /// the ability to distinguish among them.
   //@{
 
   /// Describes the kind of name lookup to perform.
   enum LookupNameKind {
     /// Ordinary name lookup, which finds ordinary names (functions,
     /// variables, typedefs, etc.) in C and most kinds of names
     /// (functions, variables, members, types, etc.) in C++.
     LookupOrdinaryName = 0,
     /// Tag name lookup, which finds the names of enums, classes,
     /// structs, and unions.
     LookupTagName,
     /// Label name lookup.
     LookupLabel,
     /// Member name lookup, which finds the names of
     /// class/struct/union members.
     LookupMemberName,
     /// Look up of an operator name (e.g., operator+) for use with
     /// operator overloading. This lookup is similar to ordinary name
     /// lookup, but will ignore any declarations that are class members.
     LookupOperatorName,
     /// Look up a name following ~ in a destructor name. This is an ordinary
     /// lookup, but prefers tags to typedefs.
     LookupDestructorName,
     /// Look up of a name that precedes the '::' scope resolution
     /// operator in C++. This lookup completely ignores operator, object,
     /// function, and enumerator names (C++ [basic.lookup.qual]p1).
     LookupNestedNameSpecifierName,
     /// Look up a namespace name within a C++ using directive or
     /// namespace alias definition, ignoring non-namespace names (C++
     /// [basic.lookup.udir]p1).
     LookupNamespaceName,
     /// Look up all declarations in a scope with the given name,
     /// including resolved using declarations.  This is appropriate
     /// for checking redeclarations for a using declaration.
     LookupUsingDeclName,
     /// Look up an ordinary name that is going to be redeclared as a
     /// name with linkage. This lookup ignores any declarations that
     /// are outside of the current scope unless they have linkage. See
     /// C99 6.2.2p4-5 and C++ [basic.link]p6.
     LookupRedeclarationWithLinkage,
     /// Look up a friend of a local class. This lookup does not look
     /// outside the innermost non-class scope. See C++11 [class.friend]p11.
     LookupLocalFriendName,
     /// Look up the name of an Objective-C protocol.
     LookupObjCProtocolName,
     /// Look up implicit 'self' parameter of an objective-c method.
     LookupObjCImplicitSelfParam,
     /// Look up the name of an OpenMP user-defined reduction operation.
     LookupOMPReductionName,
     /// Look up the name of an OpenMP user-defined mapper.
     LookupOMPMapperName,
     /// Look up any declaration with any name.
     LookupAnyName
   };
 
   /// Specifies whether (or how) name lookup is being performed for a
   /// redeclaration (vs. a reference).
   enum RedeclarationKind {
     /// The lookup is a reference to this name that is not for the
     /// purpose of redeclaring the name.
     NotForRedeclaration = 0,
     /// The lookup results will be used for redeclaration of a name,
     /// if an entity by that name already exists and is visible.
     ForVisibleRedeclaration,
     /// The lookup results will be used for redeclaration of a name
     /// with external linkage; non-visible lookup results with external linkage
     /// may also be found.
     ForExternalRedeclaration
   };
 
   RedeclarationKind forRedeclarationInCurContext() {
     // A declaration with an owning module for linkage can never link against
     // anything that is not visible. We don't need to check linkage here; if
     // the context has internal linkage, redeclaration lookup won't find things
     // from other TUs, and we can't safely compute linkage yet in general.
     if (cast<Decl>(CurContext)
             ->getOwningModuleForLinkage(/*IgnoreLinkage*/true))
       return ForVisibleRedeclaration;
     return ForExternalRedeclaration;
   }
 
   /// The possible outcomes of name lookup for a literal operator.
   enum LiteralOperatorLookupResult {
     /// The lookup resulted in an error.
     LOLR_Error,
     /// The lookup found no match but no diagnostic was issued.
     LOLR_ErrorNoDiagnostic,
     /// The lookup found a single 'cooked' literal operator, which
     /// expects a normal literal to be built and passed to it.
     LOLR_Cooked,
     /// The lookup found a single 'raw' literal operator, which expects
     /// a string literal containing the spelling of the literal token.
     LOLR_Raw,
     /// The lookup found an overload set of literal operator templates,
     /// which expect the characters of the spelling of the literal token to be
     /// passed as a non-type template argument pack.
     LOLR_Template,
     /// The lookup found an overload set of literal operator templates,
     /// which expect the character type and characters of the spelling of the
     /// string literal token to be passed as template arguments.
     LOLR_StringTemplate
   };
 
   SpecialMemberOverloadResult LookupSpecialMember(CXXRecordDecl *D,
                                                   CXXSpecialMember SM,
                                                   bool ConstArg,
                                                   bool VolatileArg,
                                                   bool RValueThis,
                                                   bool ConstThis,
                                                   bool VolatileThis);
 
   typedef std::function<void(const TypoCorrection &)> TypoDiagnosticGenerator;
   typedef std::function<ExprResult(Sema &, TypoExpr *, TypoCorrection)>
       TypoRecoveryCallback;
 
 private:
   bool CppLookupName(LookupResult &R, Scope *S);
 
   struct TypoExprState {
     std::unique_ptr<TypoCorrectionConsumer> Consumer;
     TypoDiagnosticGenerator DiagHandler;
     TypoRecoveryCallback RecoveryHandler;
     TypoExprState();
     TypoExprState(TypoExprState &&other) noexcept;
     TypoExprState &operator=(TypoExprState &&other) noexcept;
   };
 
   /// The set of unhandled TypoExprs and their associated state.
   llvm::MapVector<TypoExpr *, TypoExprState> DelayedTypos;
 
   /// Creates a new TypoExpr AST node.
   TypoExpr *createDelayedTypo(std::unique_ptr<TypoCorrectionConsumer> TCC,
                               TypoDiagnosticGenerator TDG,
                               TypoRecoveryCallback TRC);
 
   // The set of known/encountered (unique, canonicalized) NamespaceDecls.
   //
   // The boolean value will be true to indicate that the namespace was loaded
   // from an AST/PCH file, or false otherwise.
   llvm::MapVector<NamespaceDecl*, bool> KnownNamespaces;
 
   /// Whether we have already loaded known namespaces from an extenal
   /// source.
   bool LoadedExternalKnownNamespaces;
 
   /// Helper for CorrectTypo and CorrectTypoDelayed used to create and
   /// populate a new TypoCorrectionConsumer. Returns nullptr if typo correction
   /// should be skipped entirely.
   std::unique_ptr<TypoCorrectionConsumer>
   makeTypoCorrectionConsumer(const DeclarationNameInfo &Typo,
                              Sema::LookupNameKind LookupKind, Scope *S,
                              CXXScopeSpec *SS,
                              CorrectionCandidateCallback &CCC,
                              DeclContext *MemberContext, bool EnteringContext,
                              const ObjCObjectPointerType *OPT,
                              bool ErrorRecovery);
 
 public:
   const TypoExprState &getTypoExprState(TypoExpr *TE) const;
 
   /// Clears the state of the given TypoExpr.
   void clearDelayedTypo(TypoExpr *TE);
 
   /// Look up a name, looking for a single declaration.  Return
   /// null if the results were absent, ambiguous, or overloaded.
   ///
   /// It is preferable to use the elaborated form and explicitly handle
   /// ambiguity and overloaded.
   NamedDecl *LookupSingleName(Scope *S, DeclarationName Name,
                               SourceLocation Loc,
                               LookupNameKind NameKind,
                               RedeclarationKind Redecl
                                 = NotForRedeclaration);
   bool LookupBuiltin(LookupResult &R);
   bool LookupName(LookupResult &R, Scope *S,
                   bool AllowBuiltinCreation = false);
   bool LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
                            bool InUnqualifiedLookup = false);
   bool LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
                            CXXScopeSpec &SS);
   bool LookupParsedName(LookupResult &R, Scope *S, CXXScopeSpec *SS,
                         bool AllowBuiltinCreation = false,
                         bool EnteringContext = false);
   ObjCProtocolDecl *LookupProtocol(IdentifierInfo *II, SourceLocation IdLoc,
                                    RedeclarationKind Redecl
                                      = NotForRedeclaration);
   bool LookupInSuper(LookupResult &R, CXXRecordDecl *Class);
 
   void LookupOverloadedOperatorName(OverloadedOperatorKind Op, Scope *S,
                                     QualType T1, QualType T2,
                                     UnresolvedSetImpl &Functions);
 
   LabelDecl *LookupOrCreateLabel(IdentifierInfo *II, SourceLocation IdentLoc,
                                  SourceLocation GnuLabelLoc = SourceLocation());
 
   DeclContextLookupResult LookupConstructors(CXXRecordDecl *Class);
   CXXConstructorDecl *LookupDefaultConstructor(CXXRecordDecl *Class);
   CXXConstructorDecl *LookupCopyingConstructor(CXXRecordDecl *Class,
                                                unsigned Quals);
   CXXMethodDecl *LookupCopyingAssignment(CXXRecordDecl *Class, unsigned Quals,
                                          bool RValueThis, unsigned ThisQuals);
   CXXConstructorDecl *LookupMovingConstructor(CXXRecordDecl *Class,
                                               unsigned Quals);
   CXXMethodDecl *LookupMovingAssignment(CXXRecordDecl *Class, unsigned Quals,
                                         bool RValueThis, unsigned ThisQuals);
   CXXDestructorDecl *LookupDestructor(CXXRecordDecl *Class);
 
   bool checkLiteralOperatorId(const CXXScopeSpec &SS, const UnqualifiedId &Id);
   LiteralOperatorLookupResult LookupLiteralOperator(Scope *S, LookupResult &R,
                                                     ArrayRef<QualType> ArgTys,
                                                     bool AllowRaw,
                                                     bool AllowTemplate,
                                                     bool AllowStringTemplate,
                                                     bool DiagnoseMissing);
   bool isKnownName(StringRef name);
 
   /// Status of the function emission on the CUDA/HIP/OpenMP host/device attrs.
   enum class FunctionEmissionStatus {
     Emitted,
     CUDADiscarded,     // Discarded due to CUDA/HIP hostness
     OMPDiscarded,      // Discarded due to OpenMP hostness
     TemplateDiscarded, // Discarded due to uninstantiated templates
     Unknown,
   };
   FunctionEmissionStatus getEmissionStatus(FunctionDecl *Decl);
 
   // Whether the callee should be ignored in CUDA/HIP/OpenMP host/device check.
   bool shouldIgnoreInHostDeviceCheck(FunctionDecl *Callee);
 
   void ArgumentDependentLookup(DeclarationName Name, SourceLocation Loc,
                                ArrayRef<Expr *> Args, ADLResult &Functions);
 
   void LookupVisibleDecls(Scope *S, LookupNameKind Kind,
                           VisibleDeclConsumer &Consumer,
                           bool IncludeGlobalScope = true,
                           bool LoadExternal = true);
   void LookupVisibleDecls(DeclContext *Ctx, LookupNameKind Kind,
                           VisibleDeclConsumer &Consumer,
                           bool IncludeGlobalScope = true,
                           bool IncludeDependentBases = false,
                           bool LoadExternal = true);
 
   enum CorrectTypoKind {
     CTK_NonError,     // CorrectTypo used in a non error recovery situation.
     CTK_ErrorRecovery // CorrectTypo used in normal error recovery.
   };
 
   TypoCorrection CorrectTypo(const DeclarationNameInfo &Typo,
                              Sema::LookupNameKind LookupKind,
                              Scope *S, CXXScopeSpec *SS,
                              CorrectionCandidateCallback &CCC,
                              CorrectTypoKind Mode,
                              DeclContext *MemberContext = nullptr,
                              bool EnteringContext = false,
                              const ObjCObjectPointerType *OPT = nullptr,
                              bool RecordFailure = true);
 
   TypoExpr *CorrectTypoDelayed(const DeclarationNameInfo &Typo,
                                Sema::LookupNameKind LookupKind, Scope *S,
                                CXXScopeSpec *SS,
                                CorrectionCandidateCallback &CCC,
                                TypoDiagnosticGenerator TDG,
                                TypoRecoveryCallback TRC, CorrectTypoKind Mode,
                                DeclContext *MemberContext = nullptr,
                                bool EnteringContext = false,
                                const ObjCObjectPointerType *OPT = nullptr);
 
   /// Process any TypoExprs in the given Expr and its children,
   /// generating diagnostics as appropriate and returning a new Expr if there
   /// were typos that were all successfully corrected and ExprError if one or
   /// more typos could not be corrected.
   ///
   /// \param E The Expr to check for TypoExprs.
   ///
   /// \param InitDecl A VarDecl to avoid because the Expr being corrected is its
   /// initializer.
   ///
   /// \param Filter A function applied to a newly rebuilt Expr to determine if
   /// it is an acceptable/usable result from a single combination of typo
   /// corrections. As long as the filter returns ExprError, different
   /// combinations of corrections will be tried until all are exhausted.
   ExprResult
   CorrectDelayedTyposInExpr(Expr *E, VarDecl *InitDecl = nullptr,
                             llvm::function_ref<ExprResult(Expr *)> Filter =
                                 [](Expr *E) -> ExprResult { return E; });
 
   ExprResult
   CorrectDelayedTyposInExpr(Expr *E,
                             llvm::function_ref<ExprResult(Expr *)> Filter) {
     return CorrectDelayedTyposInExpr(E, nullptr, Filter);
   }
 
   ExprResult
   CorrectDelayedTyposInExpr(ExprResult ER, VarDecl *InitDecl = nullptr,
                             llvm::function_ref<ExprResult(Expr *)> Filter =
                                 [](Expr *E) -> ExprResult { return E; }) {
     return ER.isInvalid() ? ER : CorrectDelayedTyposInExpr(ER.get(), Filter);
   }
 
   ExprResult
   CorrectDelayedTyposInExpr(ExprResult ER,
                             llvm::function_ref<ExprResult(Expr *)> Filter) {
     return CorrectDelayedTyposInExpr(ER, nullptr, Filter);
   }
 
   void diagnoseTypo(const TypoCorrection &Correction,
                     const PartialDiagnostic &TypoDiag,
                     bool ErrorRecovery = true);
 
   void diagnoseTypo(const TypoCorrection &Correction,
                     const PartialDiagnostic &TypoDiag,
                     const PartialDiagnostic &PrevNote,
                     bool ErrorRecovery = true);
 
   void MarkTypoCorrectedFunctionDefinition(const NamedDecl *F);
 
   void FindAssociatedClassesAndNamespaces(SourceLocation InstantiationLoc,
                                           ArrayRef<Expr *> Args,
                                    AssociatedNamespaceSet &AssociatedNamespaces,
                                    AssociatedClassSet &AssociatedClasses);
 
   void FilterLookupForScope(LookupResult &R, DeclContext *Ctx, Scope *S,
                             bool ConsiderLinkage, bool AllowInlineNamespace);
 
   bool CheckRedeclarationModuleOwnership(NamedDecl *New, NamedDecl *Old);
 
   void DiagnoseAmbiguousLookup(LookupResult &Result);
   //@}
 
   ObjCInterfaceDecl *getObjCInterfaceDecl(IdentifierInfo *&Id,
                                           SourceLocation IdLoc,
                                           bool TypoCorrection = false);
   NamedDecl *LazilyCreateBuiltin(IdentifierInfo *II, unsigned ID,
                                  Scope *S, bool ForRedeclaration,
                                  SourceLocation Loc);
   NamedDecl *ImplicitlyDefineFunction(SourceLocation Loc, IdentifierInfo &II,
                                       Scope *S);
   void AddKnownFunctionAttributesForReplaceableGlobalAllocationFunction(
       FunctionDecl *FD);
   void AddKnownFunctionAttributes(FunctionDecl *FD);
 
   // More parsing and symbol table subroutines.
 
   void ProcessPragmaWeak(Scope *S, Decl *D);
   // Decl attributes - this routine is the top level dispatcher.
   void ProcessDeclAttributes(Scope *S, Decl *D, const Declarator &PD);
   // Helper for delayed processing of attributes.
   void ProcessDeclAttributeDelayed(Decl *D,
                                    const ParsedAttributesView &AttrList);
   void ProcessDeclAttributeList(Scope *S, Decl *D, const ParsedAttributesView &AL,
                              bool IncludeCXX11Attributes = true);
   bool ProcessAccessDeclAttributeList(AccessSpecDecl *ASDecl,
                                    const ParsedAttributesView &AttrList);
 
   void checkUnusedDeclAttributes(Declarator &D);
 
   /// Determine if type T is a valid subject for a nonnull and similar
   /// attributes. By default, we look through references (the behavior used by
   /// nonnull), but if the second parameter is true, then we treat a reference
   /// type as valid.
   bool isValidPointerAttrType(QualType T, bool RefOkay = false);
 
   bool CheckRegparmAttr(const ParsedAttr &attr, unsigned &value);
   bool CheckCallingConvAttr(const ParsedAttr &attr, CallingConv &CC,
                             const FunctionDecl *FD = nullptr);
   bool CheckAttrTarget(const ParsedAttr &CurrAttr);
   bool CheckAttrNoArgs(const ParsedAttr &CurrAttr);
   bool checkStringLiteralArgumentAttr(const ParsedAttr &Attr, unsigned ArgNum,
                                       StringRef &Str,
                                       SourceLocation *ArgLocation = nullptr);
   bool checkSectionName(SourceLocation LiteralLoc, StringRef Str);
   bool checkTargetAttr(SourceLocation LiteralLoc, StringRef Str);
   bool checkMSInheritanceAttrOnDefinition(
       CXXRecordDecl *RD, SourceRange Range, bool BestCase,
       MSInheritanceModel SemanticSpelling);
 
   void CheckAlignasUnderalignment(Decl *D);
 
   /// Adjust the calling convention of a method to be the ABI default if it
   /// wasn't specified explicitly.  This handles method types formed from
   /// function type typedefs and typename template arguments.
   void adjustMemberFunctionCC(QualType &T, bool IsStatic, bool IsCtorOrDtor,
                               SourceLocation Loc);
 
   // Check if there is an explicit attribute, but only look through parens.
   // The intent is to look for an attribute on the current declarator, but not
   // one that came from a typedef.
   bool hasExplicitCallingConv(QualType T);
 
   /// Get the outermost AttributedType node that sets a calling convention.
   /// Valid types should not have multiple attributes with different CCs.
   const AttributedType *getCallingConvAttributedType(QualType T) const;
 
   /// Stmt attributes - this routine is the top level dispatcher.
   StmtResult ProcessStmtAttributes(Stmt *Stmt,
                                    const ParsedAttributesView &Attrs,
                                    SourceRange Range);
 
   void WarnConflictingTypedMethods(ObjCMethodDecl *Method,
                                    ObjCMethodDecl *MethodDecl,
                                    bool IsProtocolMethodDecl);
 
   void CheckConflictingOverridingMethod(ObjCMethodDecl *Method,
                                    ObjCMethodDecl *Overridden,
                                    bool IsProtocolMethodDecl);
 
   /// WarnExactTypedMethods - This routine issues a warning if method
   /// implementation declaration matches exactly that of its declaration.
   void WarnExactTypedMethods(ObjCMethodDecl *Method,
                              ObjCMethodDecl *MethodDecl,
                              bool IsProtocolMethodDecl);
 
   typedef llvm::SmallPtrSet<Selector, 8> SelectorSet;
 
   /// CheckImplementationIvars - This routine checks if the instance variables
   /// listed in the implelementation match those listed in the interface.
   void CheckImplementationIvars(ObjCImplementationDecl *ImpDecl,
                                 ObjCIvarDecl **Fields, unsigned nIvars,
                                 SourceLocation Loc);
 
   /// ImplMethodsVsClassMethods - This is main routine to warn if any method
   /// remains unimplemented in the class or category \@implementation.
   void ImplMethodsVsClassMethods(Scope *S, ObjCImplDecl* IMPDecl,
                                  ObjCContainerDecl* IDecl,
                                  bool IncompleteImpl = false);
 
   /// DiagnoseUnimplementedProperties - This routine warns on those properties
   /// which must be implemented by this implementation.
   void DiagnoseUnimplementedProperties(Scope *S, ObjCImplDecl* IMPDecl,
                                        ObjCContainerDecl *CDecl,
                                        bool SynthesizeProperties);
 
   /// Diagnose any null-resettable synthesized setters.
   void diagnoseNullResettableSynthesizedSetters(const ObjCImplDecl *impDecl);
 
   /// DefaultSynthesizeProperties - This routine default synthesizes all
   /// properties which must be synthesized in the class's \@implementation.
   void DefaultSynthesizeProperties(Scope *S, ObjCImplDecl *IMPDecl,
                                    ObjCInterfaceDecl *IDecl,
                                    SourceLocation AtEnd);
   void DefaultSynthesizeProperties(Scope *S, Decl *D, SourceLocation AtEnd);
 
   /// IvarBacksCurrentMethodAccessor - This routine returns 'true' if 'IV' is
   /// an ivar synthesized for 'Method' and 'Method' is a property accessor
   /// declared in class 'IFace'.
   bool IvarBacksCurrentMethodAccessor(ObjCInterfaceDecl *IFace,
                                       ObjCMethodDecl *Method, ObjCIvarDecl *IV);
 
   /// DiagnoseUnusedBackingIvarInAccessor - Issue an 'unused' warning if ivar which
   /// backs the property is not used in the property's accessor.
   void DiagnoseUnusedBackingIvarInAccessor(Scope *S,
                                            const ObjCImplementationDecl *ImplD);
 
   /// GetIvarBackingPropertyAccessor - If method is a property setter/getter and
   /// it property has a backing ivar, returns this ivar; otherwise, returns NULL.
   /// It also returns ivar's property on success.
   ObjCIvarDecl *GetIvarBackingPropertyAccessor(const ObjCMethodDecl *Method,
                                                const ObjCPropertyDecl *&PDecl) const;
 
   /// Called by ActOnProperty to handle \@property declarations in
   /// class extensions.
   ObjCPropertyDecl *HandlePropertyInClassExtension(Scope *S,
                       SourceLocation AtLoc,
                       SourceLocation LParenLoc,
                       FieldDeclarator &FD,
                       Selector GetterSel,
                       SourceLocation GetterNameLoc,
                       Selector SetterSel,
                       SourceLocation SetterNameLoc,
                       const bool isReadWrite,
                       unsigned &Attributes,
                       const unsigned AttributesAsWritten,
                       QualType T,
                       TypeSourceInfo *TSI,
                       tok::ObjCKeywordKind MethodImplKind);
 
   /// Called by ActOnProperty and HandlePropertyInClassExtension to
   /// handle creating the ObjcPropertyDecl for a category or \@interface.
   ObjCPropertyDecl *CreatePropertyDecl(Scope *S,
                                        ObjCContainerDecl *CDecl,
                                        SourceLocation AtLoc,
                                        SourceLocation LParenLoc,
                                        FieldDeclarator &FD,
                                        Selector GetterSel,
                                        SourceLocation GetterNameLoc,
                                        Selector SetterSel,
                                        SourceLocation SetterNameLoc,
                                        const bool isReadWrite,
                                        const unsigned Attributes,
                                        const unsigned AttributesAsWritten,
                                        QualType T,
                                        TypeSourceInfo *TSI,
                                        tok::ObjCKeywordKind MethodImplKind,
                                        DeclContext *lexicalDC = nullptr);
 
   /// AtomicPropertySetterGetterRules - This routine enforces the rule (via
   /// warning) when atomic property has one but not the other user-declared
   /// setter or getter.
   void AtomicPropertySetterGetterRules(ObjCImplDecl* IMPDecl,
                                        ObjCInterfaceDecl* IDecl);
 
   void DiagnoseOwningPropertyGetterSynthesis(const ObjCImplementationDecl *D);
 
   void DiagnoseMissingDesignatedInitOverrides(
                                           const ObjCImplementationDecl *ImplD,
                                           const ObjCInterfaceDecl *IFD);
 
   void DiagnoseDuplicateIvars(ObjCInterfaceDecl *ID, ObjCInterfaceDecl *SID);
 
   enum MethodMatchStrategy {
     MMS_loose,
     MMS_strict
   };
 
   /// MatchTwoMethodDeclarations - Checks if two methods' type match and returns
   /// true, or false, accordingly.
   bool MatchTwoMethodDeclarations(const ObjCMethodDecl *Method,
                                   const ObjCMethodDecl *PrevMethod,
                                   MethodMatchStrategy strategy = MMS_strict);
 
   /// MatchAllMethodDeclarations - Check methods declaraed in interface or
   /// or protocol against those declared in their implementations.
   void MatchAllMethodDeclarations(const SelectorSet &InsMap,
                                   const SelectorSet &ClsMap,
                                   SelectorSet &InsMapSeen,
                                   SelectorSet &ClsMapSeen,
                                   ObjCImplDecl* IMPDecl,
                                   ObjCContainerDecl* IDecl,
                                   bool &IncompleteImpl,
                                   bool ImmediateClass,
                                   bool WarnCategoryMethodImpl=false);
 
   /// CheckCategoryVsClassMethodMatches - Checks that methods implemented in
   /// category matches with those implemented in its primary class and
   /// warns each time an exact match is found.
   void CheckCategoryVsClassMethodMatches(ObjCCategoryImplDecl *CatIMP);
 
   /// Add the given method to the list of globally-known methods.
   void addMethodToGlobalList(ObjCMethodList *List, ObjCMethodDecl *Method);
 
   /// Returns default addr space for method qualifiers.
   LangAS getDefaultCXXMethodAddrSpace() const;
 
 private:
   /// AddMethodToGlobalPool - Add an instance or factory method to the global
   /// pool. See descriptoin of AddInstanceMethodToGlobalPool.
   void AddMethodToGlobalPool(ObjCMethodDecl *Method, bool impl, bool instance);
 
   /// LookupMethodInGlobalPool - Returns the instance or factory method and
   /// optionally warns if there are multiple signatures.
   ObjCMethodDecl *LookupMethodInGlobalPool(Selector Sel, SourceRange R,
                                            bool receiverIdOrClass,
                                            bool instance);
 
 public:
   /// - Returns instance or factory methods in global method pool for
   /// given selector. It checks the desired kind first, if none is found, and
   /// parameter checkTheOther is set, it then checks the other kind. If no such
   /// method or only one method is found, function returns false; otherwise, it
   /// returns true.
   bool
   CollectMultipleMethodsInGlobalPool(Selector Sel,
                                      SmallVectorImpl<ObjCMethodDecl*>& Methods,
                                      bool InstanceFirst, bool CheckTheOther,
                                      const ObjCObjectType *TypeBound = nullptr);
 
   bool
   AreMultipleMethodsInGlobalPool(Selector Sel, ObjCMethodDecl *BestMethod,
                                  SourceRange R, bool receiverIdOrClass,
                                  SmallVectorImpl<ObjCMethodDecl*>& Methods);
 
   void
   DiagnoseMultipleMethodInGlobalPool(SmallVectorImpl<ObjCMethodDecl*> &Methods,
                                      Selector Sel, SourceRange R,
                                      bool receiverIdOrClass);
 
 private:
   /// - Returns a selector which best matches given argument list or
   /// nullptr if none could be found
   ObjCMethodDecl *SelectBestMethod(Selector Sel, MultiExprArg Args,
                                    bool IsInstance,
                                    SmallVectorImpl<ObjCMethodDecl*>& Methods);
 
 
   /// Record the typo correction failure and return an empty correction.
   TypoCorrection FailedCorrection(IdentifierInfo *Typo, SourceLocation TypoLoc,
                                   bool RecordFailure = true) {
     if (RecordFailure)
       TypoCorrectionFailures[Typo].insert(TypoLoc);
     return TypoCorrection();
   }
 
 public:
   /// AddInstanceMethodToGlobalPool - All instance methods in a translation
   /// unit are added to a global pool. This allows us to efficiently associate
   /// a selector with a method declaraation for purposes of typechecking
   /// messages sent to "id" (where the class of the object is unknown).
   void AddInstanceMethodToGlobalPool(ObjCMethodDecl *Method, bool impl=false) {
     AddMethodToGlobalPool(Method, impl, /*instance*/true);
   }
 
   /// AddFactoryMethodToGlobalPool - Same as above, but for factory methods.
   void AddFactoryMethodToGlobalPool(ObjCMethodDecl *Method, bool impl=false) {
     AddMethodToGlobalPool(Method, impl, /*instance*/false);
   }
 
   /// AddAnyMethodToGlobalPool - Add any method, instance or factory to global
   /// pool.
   void AddAnyMethodToGlobalPool(Decl *D);
 
   /// LookupInstanceMethodInGlobalPool - Returns the method and warns if
   /// there are multiple signatures.
   ObjCMethodDecl *LookupInstanceMethodInGlobalPool(Selector Sel, SourceRange R,
                                                    bool receiverIdOrClass=false) {
     return LookupMethodInGlobalPool(Sel, R, receiverIdOrClass,
                                     /*instance*/true);
   }
 
   /// LookupFactoryMethodInGlobalPool - Returns the method and warns if
   /// there are multiple signatures.
   ObjCMethodDecl *LookupFactoryMethodInGlobalPool(Selector Sel, SourceRange R,
                                                   bool receiverIdOrClass=false) {
     return LookupMethodInGlobalPool(Sel, R, receiverIdOrClass,
                                     /*instance*/false);
   }
 
   const ObjCMethodDecl *SelectorsForTypoCorrection(Selector Sel,
                               QualType ObjectType=QualType());
   /// LookupImplementedMethodInGlobalPool - Returns the method which has an
   /// implementation.
   ObjCMethodDecl *LookupImplementedMethodInGlobalPool(Selector Sel);
 
   /// CollectIvarsToConstructOrDestruct - Collect those ivars which require
   /// initialization.
   void CollectIvarsToConstructOrDestruct(ObjCInterfaceDecl *OI,
                                   SmallVectorImpl<ObjCIvarDecl*> &Ivars);
 
   //===--------------------------------------------------------------------===//
   // Statement Parsing Callbacks: SemaStmt.cpp.
 public:
   class FullExprArg {
   public:
     FullExprArg() : E(nullptr) { }
     FullExprArg(Sema &actions) : E(nullptr) { }
 
     ExprResult release() {
       return E;
     }
 
     Expr *get() const { return E; }
 
     Expr *operator->() {
       return E;
     }
 
   private:
     // FIXME: No need to make the entire Sema class a friend when it's just
     // Sema::MakeFullExpr that needs access to the constructor below.
     friend class Sema;
 
     explicit FullExprArg(Expr *expr) : E(expr) {}
 
     Expr *E;
   };
 
   FullExprArg MakeFullExpr(Expr *Arg) {
     return MakeFullExpr(Arg, Arg ? Arg->getExprLoc() : SourceLocation());
   }
   FullExprArg MakeFullExpr(Expr *Arg, SourceLocation CC) {
     return FullExprArg(
         ActOnFinishFullExpr(Arg, CC, /*DiscardedValue*/ false).get());
   }
   FullExprArg MakeFullDiscardedValueExpr(Expr *Arg) {
     ExprResult FE =
         ActOnFinishFullExpr(Arg, Arg ? Arg->getExprLoc() : SourceLocation(),
                             /*DiscardedValue*/ true);
     return FullExprArg(FE.get());
   }
 
   StmtResult ActOnExprStmt(ExprResult Arg, bool DiscardedValue = true);
   StmtResult ActOnExprStmtError();
 
   StmtResult ActOnNullStmt(SourceLocation SemiLoc,
                            bool HasLeadingEmptyMacro = false);
 
   void ActOnStartOfCompoundStmt(bool IsStmtExpr);
   void ActOnFinishOfCompoundStmt();
   StmtResult ActOnCompoundStmt(SourceLocation L, SourceLocation R,
                                ArrayRef<Stmt *> Elts, bool isStmtExpr);
 
   /// A RAII object to enter scope of a compound statement.
   class CompoundScopeRAII {
   public:
     CompoundScopeRAII(Sema &S, bool IsStmtExpr = false) : S(S) {
       S.ActOnStartOfCompoundStmt(IsStmtExpr);
     }
 
     ~CompoundScopeRAII() {
       S.ActOnFinishOfCompoundStmt();
     }
 
   private:
     Sema &S;
   };
 
   /// An RAII helper that pops function a function scope on exit.
   struct FunctionScopeRAII {
     Sema &S;
     bool Active;
     FunctionScopeRAII(Sema &S) : S(S), Active(true) {}
     ~FunctionScopeRAII() {
       if (Active)
         S.PopFunctionScopeInfo();
     }
     void disable() { Active = false; }
   };
 
   StmtResult ActOnDeclStmt(DeclGroupPtrTy Decl,
                                    SourceLocation StartLoc,
                                    SourceLocation EndLoc);
   void ActOnForEachDeclStmt(DeclGroupPtrTy Decl);
   StmtResult ActOnForEachLValueExpr(Expr *E);
   ExprResult ActOnCaseExpr(SourceLocation CaseLoc, ExprResult Val);
   StmtResult ActOnCaseStmt(SourceLocation CaseLoc, ExprResult LHS,
                            SourceLocation DotDotDotLoc, ExprResult RHS,
                            SourceLocation ColonLoc);
   void ActOnCaseStmtBody(Stmt *CaseStmt, Stmt *SubStmt);
 
   StmtResult ActOnDefaultStmt(SourceLocation DefaultLoc,
                                       SourceLocation ColonLoc,
                                       Stmt *SubStmt, Scope *CurScope);
   StmtResult ActOnLabelStmt(SourceLocation IdentLoc, LabelDecl *TheDecl,
                             SourceLocation ColonLoc, Stmt *SubStmt);
 
   StmtResult ActOnAttributedStmt(SourceLocation AttrLoc,
                                  ArrayRef<const Attr*> Attrs,
                                  Stmt *SubStmt);
 
   class ConditionResult;
   StmtResult ActOnIfStmt(SourceLocation IfLoc, bool IsConstexpr,
                          Stmt *InitStmt,
                          ConditionResult Cond, Stmt *ThenVal,
                          SourceLocation ElseLoc, Stmt *ElseVal);
   StmtResult BuildIfStmt(SourceLocation IfLoc, bool IsConstexpr,
                          Stmt *InitStmt,
                          ConditionResult Cond, Stmt *ThenVal,
                          SourceLocation ElseLoc, Stmt *ElseVal);
   StmtResult ActOnStartOfSwitchStmt(SourceLocation SwitchLoc,
                                     Stmt *InitStmt,
                                     ConditionResult Cond);
   StmtResult ActOnFinishSwitchStmt(SourceLocation SwitchLoc,
                                            Stmt *Switch, Stmt *Body);
   StmtResult ActOnWhileStmt(SourceLocation WhileLoc, ConditionResult Cond,
                             Stmt *Body);
   StmtResult ActOnDoStmt(SourceLocation DoLoc, Stmt *Body,
                          SourceLocation WhileLoc, SourceLocation CondLParen,
                          Expr *Cond, SourceLocation CondRParen);
 
   StmtResult ActOnForStmt(SourceLocation ForLoc,
                           SourceLocation LParenLoc,
                           Stmt *First,
                           ConditionResult Second,
                           FullExprArg Third,
                           SourceLocation RParenLoc,
                           Stmt *Body);
   ExprResult CheckObjCForCollectionOperand(SourceLocation forLoc,
                                            Expr *collection);
   StmtResult ActOnObjCForCollectionStmt(SourceLocation ForColLoc,
                                         Stmt *First, Expr *collection,
                                         SourceLocation RParenLoc);
   StmtResult FinishObjCForCollectionStmt(Stmt *ForCollection, Stmt *Body);
 
   enum BuildForRangeKind {
     /// Initial building of a for-range statement.
     BFRK_Build,
     /// Instantiation or recovery rebuild of a for-range statement. Don't
     /// attempt any typo-correction.
     BFRK_Rebuild,
     /// Determining whether a for-range statement could be built. Avoid any
     /// unnecessary or irreversible actions.
     BFRK_Check
   };
 
   StmtResult ActOnCXXForRangeStmt(Scope *S, SourceLocation ForLoc,
                                   SourceLocation CoawaitLoc,
                                   Stmt *InitStmt,
                                   Stmt *LoopVar,
                                   SourceLocation ColonLoc, Expr *Collection,
                                   SourceLocation RParenLoc,
                                   BuildForRangeKind Kind);
   StmtResult BuildCXXForRangeStmt(SourceLocation ForLoc,
                                   SourceLocation CoawaitLoc,
                                   Stmt *InitStmt,
                                   SourceLocation ColonLoc,
                                   Stmt *RangeDecl, Stmt *Begin, Stmt *End,
                                   Expr *Cond, Expr *Inc,
                                   Stmt *LoopVarDecl,
                                   SourceLocation RParenLoc,
                                   BuildForRangeKind Kind);
   StmtResult FinishCXXForRangeStmt(Stmt *ForRange, Stmt *Body);
 
   StmtResult ActOnGotoStmt(SourceLocation GotoLoc,
                            SourceLocation LabelLoc,
                            LabelDecl *TheDecl);
   StmtResult ActOnIndirectGotoStmt(SourceLocation GotoLoc,
                                    SourceLocation StarLoc,
                                    Expr *DestExp);
   StmtResult ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope);
   StmtResult ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope);
 
   void ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
                                 CapturedRegionKind Kind, unsigned NumParams);
   typedef std::pair<StringRef, QualType> CapturedParamNameType;
   void ActOnCapturedRegionStart(SourceLocation Loc, Scope *CurScope,
                                 CapturedRegionKind Kind,
                                 ArrayRef<CapturedParamNameType> Params,
                                 unsigned OpenMPCaptureLevel = 0);
   StmtResult ActOnCapturedRegionEnd(Stmt *S);
   void ActOnCapturedRegionError();
   RecordDecl *CreateCapturedStmtRecordDecl(CapturedDecl *&CD,
                                            SourceLocation Loc,
                                            unsigned NumParams);
 
   enum CopyElisionSemanticsKind {
     CES_Strict = 0,
     CES_AllowParameters = 1,
     CES_AllowDifferentTypes = 2,
     CES_AllowExceptionVariables = 4,
     CES_FormerDefault = (CES_AllowParameters),
     CES_Default = (CES_AllowParameters | CES_AllowDifferentTypes),
     CES_AsIfByStdMove = (CES_AllowParameters | CES_AllowDifferentTypes |
                          CES_AllowExceptionVariables),
   };
 
   VarDecl *getCopyElisionCandidate(QualType ReturnType, Expr *E,
                                    CopyElisionSemanticsKind CESK);
   bool isCopyElisionCandidate(QualType ReturnType, const VarDecl *VD,
                               CopyElisionSemanticsKind CESK);
 
   StmtResult ActOnReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp,
                              Scope *CurScope);
   StmtResult BuildReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp);
   StmtResult ActOnCapScopeReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp);
 
   StmtResult ActOnGCCAsmStmt(SourceLocation AsmLoc, bool IsSimple,
                              bool IsVolatile, unsigned NumOutputs,
                              unsigned NumInputs, IdentifierInfo **Names,
                              MultiExprArg Constraints, MultiExprArg Exprs,
                              Expr *AsmString, MultiExprArg Clobbers,
                              unsigned NumLabels,
                              SourceLocation RParenLoc);
 
   void FillInlineAsmIdentifierInfo(Expr *Res,
                                    llvm::InlineAsmIdentifierInfo &Info);
   ExprResult LookupInlineAsmIdentifier(CXXScopeSpec &SS,
                                        SourceLocation TemplateKWLoc,
                                        UnqualifiedId &Id,
                                        bool IsUnevaluatedContext);
   bool LookupInlineAsmField(StringRef Base, StringRef Member,
                             unsigned &Offset, SourceLocation AsmLoc);
   ExprResult LookupInlineAsmVarDeclField(Expr *RefExpr, StringRef Member,
                                          SourceLocation AsmLoc);
   StmtResult ActOnMSAsmStmt(SourceLocation AsmLoc, SourceLocation LBraceLoc,
                             ArrayRef<Token> AsmToks,
                             StringRef AsmString,
                             unsigned NumOutputs, unsigned NumInputs,
                             ArrayRef<StringRef> Constraints,
                             ArrayRef<StringRef> Clobbers,
                             ArrayRef<Expr*> Exprs,
                             SourceLocation EndLoc);
   LabelDecl *GetOrCreateMSAsmLabel(StringRef ExternalLabelName,
                                    SourceLocation Location,
                                    bool AlwaysCreate);
 
   VarDecl *BuildObjCExceptionDecl(TypeSourceInfo *TInfo, QualType ExceptionType,
                                   SourceLocation StartLoc,
                                   SourceLocation IdLoc, IdentifierInfo *Id,
                                   bool Invalid = false);
 
   Decl *ActOnObjCExceptionDecl(Scope *S, Declarator &D);
 
   StmtResult ActOnObjCAtCatchStmt(SourceLocation AtLoc, SourceLocation RParen,
                                   Decl *Parm, Stmt *Body);
 
   StmtResult ActOnObjCAtFinallyStmt(SourceLocation AtLoc, Stmt *Body);
 
   StmtResult ActOnObjCAtTryStmt(SourceLocation AtLoc, Stmt *Try,
                                 MultiStmtArg Catch, Stmt *Finally);
 
   StmtResult BuildObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw);
   StmtResult ActOnObjCAtThrowStmt(SourceLocation AtLoc, Expr *Throw,
                                   Scope *CurScope);
   ExprResult ActOnObjCAtSynchronizedOperand(SourceLocation atLoc,
                                             Expr *operand);
   StmtResult ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc,
                                          Expr *SynchExpr,
                                          Stmt *SynchBody);
 
   StmtResult ActOnObjCAutoreleasePoolStmt(SourceLocation AtLoc, Stmt *Body);
 
   VarDecl *BuildExceptionDeclaration(Scope *S, TypeSourceInfo *TInfo,
                                      SourceLocation StartLoc,
                                      SourceLocation IdLoc,
                                      IdentifierInfo *Id);
 
   Decl *ActOnExceptionDeclarator(Scope *S, Declarator &D);
 
   StmtResult ActOnCXXCatchBlock(SourceLocation CatchLoc,
                                 Decl *ExDecl, Stmt *HandlerBlock);
   StmtResult ActOnCXXTryBlock(SourceLocation TryLoc, Stmt *TryBlock,
                               ArrayRef<Stmt *> Handlers);
 
   StmtResult ActOnSEHTryBlock(bool IsCXXTry, // try (true) or __try (false) ?
                               SourceLocation TryLoc, Stmt *TryBlock,
                               Stmt *Handler);
   StmtResult ActOnSEHExceptBlock(SourceLocation Loc,
                                  Expr *FilterExpr,
                                  Stmt *Block);
   void ActOnStartSEHFinallyBlock();
   void ActOnAbortSEHFinallyBlock();
   StmtResult ActOnFinishSEHFinallyBlock(SourceLocation Loc, Stmt *Block);
   StmtResult ActOnSEHLeaveStmt(SourceLocation Loc, Scope *CurScope);
 
   void DiagnoseReturnInConstructorExceptionHandler(CXXTryStmt *TryBlock);
 
   bool ShouldWarnIfUnusedFileScopedDecl(const DeclaratorDecl *D) const;
 
   /// If it's a file scoped decl that must warn if not used, keep track
   /// of it.
   void MarkUnusedFileScopedDecl(const DeclaratorDecl *D);
 
   /// DiagnoseUnusedExprResult - If the statement passed in is an expression
   /// whose result is unused, warn.
   void DiagnoseUnusedExprResult(const Stmt *S);
   void DiagnoseUnusedNestedTypedefs(const RecordDecl *D);
   void DiagnoseUnusedDecl(const NamedDecl *ND);
 
   /// Emit \p DiagID if statement located on \p StmtLoc has a suspicious null
   /// statement as a \p Body, and it is located on the same line.
   ///
   /// This helps prevent bugs due to typos, such as:
   ///     if (condition);
   ///       do_stuff();
   void DiagnoseEmptyStmtBody(SourceLocation StmtLoc,
                              const Stmt *Body,
                              unsigned DiagID);
 
   /// Warn if a for/while loop statement \p S, which is followed by
   /// \p PossibleBody, has a suspicious null statement as a body.
   void DiagnoseEmptyLoopBody(const Stmt *S,
                              const Stmt *PossibleBody);
 
   /// Warn if a value is moved to itself.
   void DiagnoseSelfMove(const Expr *LHSExpr, const Expr *RHSExpr,
                         SourceLocation OpLoc);
 
   /// Warn if we're implicitly casting from a _Nullable pointer type to a
   /// _Nonnull one.
   void diagnoseNullableToNonnullConversion(QualType DstType, QualType SrcType,
                                            SourceLocation Loc);
 
   /// Warn when implicitly casting 0 to nullptr.
   void diagnoseZeroToNullptrConversion(CastKind Kind, const Expr *E);
 
   ParsingDeclState PushParsingDeclaration(sema::DelayedDiagnosticPool &pool) {
     return DelayedDiagnostics.push(pool);
   }
   void PopParsingDeclaration(ParsingDeclState state, Decl *decl);
 
   typedef ProcessingContextState ParsingClassState;
   ParsingClassState PushParsingClass() {
     ParsingClassDepth++;
     return DelayedDiagnostics.pushUndelayed();
   }
   void PopParsingClass(ParsingClassState state) {
     ParsingClassDepth--;
     DelayedDiagnostics.popUndelayed(state);
   }
 
   void redelayDiagnostics(sema::DelayedDiagnosticPool &pool);
 
   void DiagnoseAvailabilityOfDecl(NamedDecl *D, ArrayRef<SourceLocation> Locs,
                                   const ObjCInterfaceDecl *UnknownObjCClass,
                                   bool ObjCPropertyAccess,
                                   bool AvoidPartialAvailabilityChecks = false,
                                   ObjCInterfaceDecl *ClassReceiver = nullptr);
 
   bool makeUnavailableInSystemHeader(SourceLocation loc,
                                      UnavailableAttr::ImplicitReason reason);
 
   /// Issue any -Wunguarded-availability warnings in \c FD
   void DiagnoseUnguardedAvailabilityViolations(Decl *FD);
 
   void handleDelayedAvailabilityCheck(sema::DelayedDiagnostic &DD, Decl *Ctx);
 
   //===--------------------------------------------------------------------===//
   // Expression Parsing Callbacks: SemaExpr.cpp.
 
   bool CanUseDecl(NamedDecl *D, bool TreatUnavailableAsInvalid);
   bool DiagnoseUseOfDecl(NamedDecl *D, ArrayRef<SourceLocation> Locs,
                          const ObjCInterfaceDecl *UnknownObjCClass = nullptr,
                          bool ObjCPropertyAccess = false,
                          bool AvoidPartialAvailabilityChecks = false,
                          ObjCInterfaceDecl *ClassReciever = nullptr);
   void NoteDeletedFunction(FunctionDecl *FD);
   void NoteDeletedInheritingConstructor(CXXConstructorDecl *CD);
   bool DiagnosePropertyAccessorMismatch(ObjCPropertyDecl *PD,
                                         ObjCMethodDecl *Getter,
                                         SourceLocation Loc);
   void DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc,
                              ArrayRef<Expr *> Args);
 
   void PushExpressionEvaluationContext(
       ExpressionEvaluationContext NewContext, Decl *LambdaContextDecl = nullptr,
       ExpressionEvaluationContextRecord::ExpressionKind Type =
           ExpressionEvaluationContextRecord::EK_Other);
   enum ReuseLambdaContextDecl_t { ReuseLambdaContextDecl };
   void PushExpressionEvaluationContext(
       ExpressionEvaluationContext NewContext, ReuseLambdaContextDecl_t,
       ExpressionEvaluationContextRecord::ExpressionKind Type =
           ExpressionEvaluationContextRecord::EK_Other);
   void PopExpressionEvaluationContext();
 
   void DiscardCleanupsInEvaluationContext();
 
   ExprResult TransformToPotentiallyEvaluated(Expr *E);
   ExprResult HandleExprEvaluationContextForTypeof(Expr *E);
 
   ExprResult CheckUnevaluatedOperand(Expr *E);
   void CheckUnusedVolatileAssignment(Expr *E);
 
   ExprResult ActOnConstantExpression(ExprResult Res);
 
   // Functions for marking a declaration referenced.  These functions also
   // contain the relevant logic for marking if a reference to a function or
   // variable is an odr-use (in the C++11 sense).  There are separate variants
   // for expressions referring to a decl; these exist because odr-use marking
   // needs to be delayed for some constant variables when we build one of the
   // named expressions.
   //
   // MightBeOdrUse indicates whether the use could possibly be an odr-use, and
   // should usually be true. This only needs to be set to false if the lack of
   // odr-use cannot be determined from the current context (for instance,
   // because the name denotes a virtual function and was written without an
   // explicit nested-name-specifier).
   void MarkAnyDeclReferenced(SourceLocation Loc, Decl *D, bool MightBeOdrUse);
   void MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func,
                               bool MightBeOdrUse = true);
   void MarkVariableReferenced(SourceLocation Loc, VarDecl *Var);
   void MarkDeclRefReferenced(DeclRefExpr *E, const Expr *Base = nullptr);
   void MarkMemberReferenced(MemberExpr *E);
   void MarkFunctionParmPackReferenced(FunctionParmPackExpr *E);
   void MarkCaptureUsedInEnclosingContext(VarDecl *Capture, SourceLocation Loc,
                                          unsigned CapturingScopeIndex);
 
   ExprResult CheckLValueToRValueConversionOperand(Expr *E);
   void CleanupVarDeclMarking();
 
   enum TryCaptureKind {
     TryCapture_Implicit, TryCapture_ExplicitByVal, TryCapture_ExplicitByRef
   };
 
   /// Try to capture the given variable.
   ///
   /// \param Var The variable to capture.
   ///
   /// \param Loc The location at which the capture occurs.
   ///
   /// \param Kind The kind of capture, which may be implicit (for either a
   /// block or a lambda), or explicit by-value or by-reference (for a lambda).
   ///
   /// \param EllipsisLoc The location of the ellipsis, if one is provided in
   /// an explicit lambda capture.
   ///
   /// \param BuildAndDiagnose Whether we are actually supposed to add the
   /// captures or diagnose errors. If false, this routine merely check whether
   /// the capture can occur without performing the capture itself or complaining
   /// if the variable cannot be captured.
   ///
   /// \param CaptureType Will be set to the type of the field used to capture
   /// this variable in the innermost block or lambda. Only valid when the
   /// variable can be captured.
   ///
   /// \param DeclRefType Will be set to the type of a reference to the capture
   /// from within the current scope. Only valid when the variable can be
   /// captured.
   ///
   /// \param FunctionScopeIndexToStopAt If non-null, it points to the index
   /// of the FunctionScopeInfo stack beyond which we do not attempt to capture.
   /// This is useful when enclosing lambdas must speculatively capture
   /// variables that may or may not be used in certain specializations of
   /// a nested generic lambda.
   ///
   /// \returns true if an error occurred (i.e., the variable cannot be
   /// captured) and false if the capture succeeded.
   bool tryCaptureVariable(VarDecl *Var, SourceLocation Loc, TryCaptureKind Kind,
                           SourceLocation EllipsisLoc, bool BuildAndDiagnose,
                           QualType &CaptureType,
                           QualType &DeclRefType,
                           const unsigned *const FunctionScopeIndexToStopAt);
 
   /// Try to capture the given variable.
   bool tryCaptureVariable(VarDecl *Var, SourceLocation Loc,
                           TryCaptureKind Kind = TryCapture_Implicit,
                           SourceLocation EllipsisLoc = SourceLocation());
 
   /// Checks if the variable must be captured.
   bool NeedToCaptureVariable(VarDecl *Var, SourceLocation Loc);
 
   /// Given a variable, determine the type that a reference to that
   /// variable will have in the given scope.
   QualType getCapturedDeclRefType(VarDecl *Var, SourceLocation Loc);
 
   /// Mark all of the declarations referenced within a particular AST node as
   /// referenced. Used when template instantiation instantiates a non-dependent
   /// type -- entities referenced by the type are now referenced.
   void MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T);
   void MarkDeclarationsReferencedInExpr(Expr *E,
                                         bool SkipLocalVariables = false);
 
   /// Try to recover by turning the given expression into a
   /// call.  Returns true if recovery was attempted or an error was
   /// emitted; this may also leave the ExprResult invalid.
   bool tryToRecoverWithCall(ExprResult &E, const PartialDiagnostic &PD,
                             bool ForceComplain = false,
                             bool (*IsPlausibleResult)(QualType) = nullptr);
 
   /// Figure out if an expression could be turned into a call.
   bool tryExprAsCall(Expr &E, QualType &ZeroArgCallReturnTy,
                      UnresolvedSetImpl &NonTemplateOverloads);
 
   /// Conditionally issue a diagnostic based on the current
   /// evaluation context.
   ///
   /// \param Statement If Statement is non-null, delay reporting the
   /// diagnostic until the function body is parsed, and then do a basic
   /// reachability analysis to determine if the statement is reachable.
   /// If it is unreachable, the diagnostic will not be emitted.
   bool DiagRuntimeBehavior(SourceLocation Loc, const Stmt *Statement,
                            const PartialDiagnostic &PD);
   /// Similar, but diagnostic is only produced if all the specified statements
   /// are reachable.
   bool DiagRuntimeBehavior(SourceLocation Loc, ArrayRef<const Stmt*> Stmts,
                            const PartialDiagnostic &PD);
 
   // Primary Expressions.
   SourceRange getExprRange(Expr *E) const;
 
   ExprResult ActOnIdExpression(
       Scope *S, CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
       UnqualifiedId &Id, bool HasTrailingLParen, bool IsAddressOfOperand,
       CorrectionCandidateCallback *CCC = nullptr,
       bool IsInlineAsmIdentifier = false, Token *KeywordReplacement = nullptr);
 
   void DecomposeUnqualifiedId(const UnqualifiedId &Id,
                               TemplateArgumentListInfo &Buffer,
                               DeclarationNameInfo &NameInfo,
                               const TemplateArgumentListInfo *&TemplateArgs);
 
   bool
   DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
                       CorrectionCandidateCallback &CCC,
                       TemplateArgumentListInfo *ExplicitTemplateArgs = nullptr,
                       ArrayRef<Expr *> Args = None, TypoExpr **Out = nullptr);
 
   DeclResult LookupIvarInObjCMethod(LookupResult &Lookup, Scope *S,
                                     IdentifierInfo *II);
   ExprResult BuildIvarRefExpr(Scope *S, SourceLocation Loc, ObjCIvarDecl *IV);
 
   ExprResult LookupInObjCMethod(LookupResult &LookUp, Scope *S,
                                 IdentifierInfo *II,
                                 bool AllowBuiltinCreation=false);
 
   ExprResult ActOnDependentIdExpression(const CXXScopeSpec &SS,
                                         SourceLocation TemplateKWLoc,
                                         const DeclarationNameInfo &NameInfo,
                                         bool isAddressOfOperand,
                                 const TemplateArgumentListInfo *TemplateArgs);
 
   /// If \p D cannot be odr-used in the current expression evaluation context,
   /// return a reason explaining why. Otherwise, return NOUR_None.
   NonOdrUseReason getNonOdrUseReasonInCurrentContext(ValueDecl *D);
 
   DeclRefExpr *BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
                                 SourceLocation Loc,
                                 const CXXScopeSpec *SS = nullptr);
   DeclRefExpr *
   BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
                    const DeclarationNameInfo &NameInfo,
                    const CXXScopeSpec *SS = nullptr,
                    NamedDecl *FoundD = nullptr,
                    SourceLocation TemplateKWLoc = SourceLocation(),
                    const TemplateArgumentListInfo *TemplateArgs = nullptr);
   DeclRefExpr *
   BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
                    const DeclarationNameInfo &NameInfo,
                    NestedNameSpecifierLoc NNS,
                    NamedDecl *FoundD = nullptr,
                    SourceLocation TemplateKWLoc = SourceLocation(),
                    const TemplateArgumentListInfo *TemplateArgs = nullptr);
 
   ExprResult
   BuildAnonymousStructUnionMemberReference(
       const CXXScopeSpec &SS,
       SourceLocation nameLoc,
       IndirectFieldDecl *indirectField,
       DeclAccessPair FoundDecl = DeclAccessPair::make(nullptr, AS_none),
       Expr *baseObjectExpr = nullptr,
       SourceLocation opLoc = SourceLocation());
 
   ExprResult BuildPossibleImplicitMemberExpr(const CXXScopeSpec &SS,
                                              SourceLocation TemplateKWLoc,
                                              LookupResult &R,
                                 const TemplateArgumentListInfo *TemplateArgs,
                                              const Scope *S);
   ExprResult BuildImplicitMemberExpr(const CXXScopeSpec &SS,
                                      SourceLocation TemplateKWLoc,
                                      LookupResult &R,
                                 const TemplateArgumentListInfo *TemplateArgs,
                                      bool IsDefiniteInstance,
                                      const Scope *S);
   bool UseArgumentDependentLookup(const CXXScopeSpec &SS,
                                   const LookupResult &R,
                                   bool HasTrailingLParen);
 
   ExprResult
   BuildQualifiedDeclarationNameExpr(CXXScopeSpec &SS,
                                     const DeclarationNameInfo &NameInfo,
                                     bool IsAddressOfOperand, const Scope *S,
                                     TypeSourceInfo **RecoveryTSI = nullptr);
 
   ExprResult BuildDependentDeclRefExpr(const CXXScopeSpec &SS,
                                        SourceLocation TemplateKWLoc,
                                 const DeclarationNameInfo &NameInfo,
                                 const TemplateArgumentListInfo *TemplateArgs);
 
   ExprResult BuildDeclarationNameExpr(const CXXScopeSpec &SS,
                                       LookupResult &R,
                                       bool NeedsADL,
                                       bool AcceptInvalidDecl = false);
   ExprResult BuildDeclarationNameExpr(
       const CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo, NamedDecl *D,
       NamedDecl *FoundD = nullptr,
       const TemplateArgumentListInfo *TemplateArgs = nullptr,
       bool AcceptInvalidDecl = false);
 
   ExprResult BuildLiteralOperatorCall(LookupResult &R,
                       DeclarationNameInfo &SuffixInfo,
                       ArrayRef<Expr *> Args,
                       SourceLocation LitEndLoc,
                       TemplateArgumentListInfo *ExplicitTemplateArgs = nullptr);
 
   ExprResult BuildPredefinedExpr(SourceLocation Loc,
                                  PredefinedExpr::IdentKind IK);
   ExprResult ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind);
   ExprResult ActOnIntegerConstant(SourceLocation Loc, uint64_t Val);
 
   bool CheckLoopHintExpr(Expr *E, SourceLocation Loc);
 
   ExprResult ActOnNumericConstant(const Token &Tok, Scope *UDLScope = nullptr);
   ExprResult ActOnCharacterConstant(const Token &Tok,
                                     Scope *UDLScope = nullptr);
   ExprResult ActOnParenExpr(SourceLocation L, SourceLocation R, Expr *E);
   ExprResult ActOnParenListExpr(SourceLocation L,
                                 SourceLocation R,
                                 MultiExprArg Val);
 
   /// ActOnStringLiteral - The specified tokens were lexed as pasted string
   /// fragments (e.g. "foo" "bar" L"baz").
   ExprResult ActOnStringLiteral(ArrayRef<Token> StringToks,
                                 Scope *UDLScope = nullptr);
 
   ExprResult ActOnGenericSelectionExpr(SourceLocation KeyLoc,
                                        SourceLocation DefaultLoc,
                                        SourceLocation RParenLoc,
                                        Expr *ControllingExpr,
                                        ArrayRef<ParsedType> ArgTypes,
                                        ArrayRef<Expr *> ArgExprs);
   ExprResult CreateGenericSelectionExpr(SourceLocation KeyLoc,
                                         SourceLocation DefaultLoc,
                                         SourceLocation RParenLoc,
                                         Expr *ControllingExpr,
                                         ArrayRef<TypeSourceInfo *> Types,
                                         ArrayRef<Expr *> Exprs);
 
   // Binary/Unary Operators.  'Tok' is the token for the operator.
   ExprResult CreateBuiltinUnaryOp(SourceLocation OpLoc, UnaryOperatorKind Opc,
                                   Expr *InputExpr);
   ExprResult BuildUnaryOp(Scope *S, SourceLocation OpLoc,
                           UnaryOperatorKind Opc, Expr *Input);
   ExprResult ActOnUnaryOp(Scope *S, SourceLocation OpLoc,
                           tok::TokenKind Op, Expr *Input);
 
   bool isQualifiedMemberAccess(Expr *E);
   QualType CheckAddressOfOperand(ExprResult &Operand, SourceLocation OpLoc);
 
   ExprResult CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo,
                                             SourceLocation OpLoc,
                                             UnaryExprOrTypeTrait ExprKind,
                                             SourceRange R);
   ExprResult CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc,
                                             UnaryExprOrTypeTrait ExprKind);
   ExprResult
     ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc,
                                   UnaryExprOrTypeTrait ExprKind,
                                   bool IsType, void *TyOrEx,
                                   SourceRange ArgRange);
 
   ExprResult CheckPlaceholderExpr(Expr *E);
   bool CheckVecStepExpr(Expr *E);
 
   bool CheckUnaryExprOrTypeTraitOperand(Expr *E, UnaryExprOrTypeTrait ExprKind);
   bool CheckUnaryExprOrTypeTraitOperand(QualType ExprType, SourceLocation OpLoc,
                                         SourceRange ExprRange,
                                         UnaryExprOrTypeTrait ExprKind);
   ExprResult ActOnSizeofParameterPackExpr(Scope *S,
                                           SourceLocation OpLoc,
                                           IdentifierInfo &Name,
                                           SourceLocation NameLoc,
                                           SourceLocation RParenLoc);
   ExprResult ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc,
                                  tok::TokenKind Kind, Expr *Input);
 
   ExprResult ActOnArraySubscriptExpr(Scope *S, Expr *Base, SourceLocation LLoc,
                                      Expr *Idx, SourceLocation RLoc);
   ExprResult CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc,
                                              Expr *Idx, SourceLocation RLoc);
   ExprResult ActOnOMPArraySectionExpr(Expr *Base, SourceLocation LBLoc,
                                       Expr *LowerBound, SourceLocation ColonLoc,
                                       Expr *Length, SourceLocation RBLoc);
 
   // This struct is for use by ActOnMemberAccess to allow
   // BuildMemberReferenceExpr to be able to reinvoke ActOnMemberAccess after
   // changing the access operator from a '.' to a '->' (to see if that is the
   // change needed to fix an error about an unknown member, e.g. when the class
   // defines a custom operator->).
   struct ActOnMemberAccessExtraArgs {
     Scope *S;
     UnqualifiedId &Id;
     Decl *ObjCImpDecl;
   };
 
   ExprResult BuildMemberReferenceExpr(
       Expr *Base, QualType BaseType, SourceLocation OpLoc, bool IsArrow,
       CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
       NamedDecl *FirstQualifierInScope, const DeclarationNameInfo &NameInfo,
       const TemplateArgumentListInfo *TemplateArgs,
       const Scope *S,
       ActOnMemberAccessExtraArgs *ExtraArgs = nullptr);
 
   ExprResult
   BuildMemberReferenceExpr(Expr *Base, QualType BaseType, SourceLocation OpLoc,
                            bool IsArrow, const CXXScopeSpec &SS,
                            SourceLocation TemplateKWLoc,
                            NamedDecl *FirstQualifierInScope, LookupResult &R,
                            const TemplateArgumentListInfo *TemplateArgs,
                            const Scope *S,
                            bool SuppressQualifierCheck = false,
                            ActOnMemberAccessExtraArgs *ExtraArgs = nullptr);
 
   ExprResult BuildFieldReferenceExpr(Expr *BaseExpr, bool IsArrow,
                                      SourceLocation OpLoc,
                                      const CXXScopeSpec &SS, FieldDecl *Field,
                                      DeclAccessPair FoundDecl,
                                      const DeclarationNameInfo &MemberNameInfo);
 
   ExprResult PerformMemberExprBaseConversion(Expr *Base, bool IsArrow);
 
   bool CheckQualifiedMemberReference(Expr *BaseExpr, QualType BaseType,
                                      const CXXScopeSpec &SS,
                                      const LookupResult &R);
 
   ExprResult ActOnDependentMemberExpr(Expr *Base, QualType BaseType,
                                       bool IsArrow, SourceLocation OpLoc,
                                       const CXXScopeSpec &SS,
                                       SourceLocation TemplateKWLoc,
                                       NamedDecl *FirstQualifierInScope,
                                const DeclarationNameInfo &NameInfo,
                                const TemplateArgumentListInfo *TemplateArgs);
 
   ExprResult ActOnMemberAccessExpr(Scope *S, Expr *Base,
                                    SourceLocation OpLoc,
                                    tok::TokenKind OpKind,
                                    CXXScopeSpec &SS,
                                    SourceLocation TemplateKWLoc,
                                    UnqualifiedId &Member,
                                    Decl *ObjCImpDecl);
 
   MemberExpr *
   BuildMemberExpr(Expr *Base, bool IsArrow, SourceLocation OpLoc,
                   const CXXScopeSpec *SS, SourceLocation TemplateKWLoc,
                   ValueDecl *Member, DeclAccessPair FoundDecl,
                   bool HadMultipleCandidates,
                   const DeclarationNameInfo &MemberNameInfo, QualType Ty,
                   ExprValueKind VK, ExprObjectKind OK,
                   const TemplateArgumentListInfo *TemplateArgs = nullptr);
   MemberExpr *
   BuildMemberExpr(Expr *Base, bool IsArrow, SourceLocation OpLoc,
                   NestedNameSpecifierLoc NNS, SourceLocation TemplateKWLoc,
                   ValueDecl *Member, DeclAccessPair FoundDecl,
                   bool HadMultipleCandidates,
                   const DeclarationNameInfo &MemberNameInfo, QualType Ty,
                   ExprValueKind VK, ExprObjectKind OK,
                   const TemplateArgumentListInfo *TemplateArgs = nullptr);
 
   void ActOnDefaultCtorInitializers(Decl *CDtorDecl);
   bool ConvertArgumentsForCall(CallExpr *Call, Expr *Fn,
                                FunctionDecl *FDecl,
                                const FunctionProtoType *Proto,
                                ArrayRef<Expr *> Args,
                                SourceLocation RParenLoc,
                                bool ExecConfig = false);
   void CheckStaticArrayArgument(SourceLocation CallLoc,
                                 ParmVarDecl *Param,
                                 const Expr *ArgExpr);
 
   /// ActOnCallExpr - Handle a call to Fn with the specified array of arguments.
   /// This provides the location of the left/right parens and a list of comma
   /// locations.
   ExprResult ActOnCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc,
                            MultiExprArg ArgExprs, SourceLocation RParenLoc,
                            Expr *ExecConfig = nullptr);
   ExprResult BuildCallExpr(Scope *S, Expr *Fn, SourceLocation LParenLoc,
                            MultiExprArg ArgExprs, SourceLocation RParenLoc,
                            Expr *ExecConfig = nullptr,
                            bool IsExecConfig = false);
   enum class AtomicArgumentOrder { API, AST };
   ExprResult
   BuildAtomicExpr(SourceRange CallRange, SourceRange ExprRange,
                   SourceLocation RParenLoc, MultiExprArg Args,
                   AtomicExpr::AtomicOp Op,
                   AtomicArgumentOrder ArgOrder = AtomicArgumentOrder::API);
   ExprResult
   BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl, SourceLocation LParenLoc,
                         ArrayRef<Expr *> Arg, SourceLocation RParenLoc,
                         Expr *Config = nullptr, bool IsExecConfig = false,
                         ADLCallKind UsesADL = ADLCallKind::NotADL);
 
   ExprResult ActOnCUDAExecConfigExpr(Scope *S, SourceLocation LLLLoc,
                                      MultiExprArg ExecConfig,
                                      SourceLocation GGGLoc);
 
   ExprResult ActOnCastExpr(Scope *S, SourceLocation LParenLoc,
                            Declarator &D, ParsedType &Ty,
                            SourceLocation RParenLoc, Expr *CastExpr);
   ExprResult BuildCStyleCastExpr(SourceLocation LParenLoc,
                                  TypeSourceInfo *Ty,
                                  SourceLocation RParenLoc,
                                  Expr *Op);
   CastKind PrepareScalarCast(ExprResult &src, QualType destType);
 
   /// Build an altivec or OpenCL literal.
   ExprResult BuildVectorLiteral(SourceLocation LParenLoc,
                                 SourceLocation RParenLoc, Expr *E,
                                 TypeSourceInfo *TInfo);
 
   ExprResult MaybeConvertParenListExprToParenExpr(Scope *S, Expr *ME);
 
   ExprResult ActOnCompoundLiteral(SourceLocation LParenLoc,
                                   ParsedType Ty,
                                   SourceLocation RParenLoc,
                                   Expr *InitExpr);
 
   ExprResult BuildCompoundLiteralExpr(SourceLocation LParenLoc,
                                       TypeSourceInfo *TInfo,
                                       SourceLocation RParenLoc,
                                       Expr *LiteralExpr);
 
   ExprResult ActOnInitList(SourceLocation LBraceLoc,
                            MultiExprArg InitArgList,
                            SourceLocation RBraceLoc);
 
   ExprResult BuildInitList(SourceLocation LBraceLoc,
                            MultiExprArg InitArgList,
                            SourceLocation RBraceLoc);
 
   ExprResult ActOnDesignatedInitializer(Designation &Desig,
                                         SourceLocation EqualOrColonLoc,
                                         bool GNUSyntax,
                                         ExprResult Init);
 
 private:
   static BinaryOperatorKind ConvertTokenKindToBinaryOpcode(tok::TokenKind Kind);
 
 public:
   ExprResult ActOnBinOp(Scope *S, SourceLocation TokLoc,
                         tok::TokenKind Kind, Expr *LHSExpr, Expr *RHSExpr);
   ExprResult BuildBinOp(Scope *S, SourceLocation OpLoc,
                         BinaryOperatorKind Opc, Expr *LHSExpr, Expr *RHSExpr);
   ExprResult CreateBuiltinBinOp(SourceLocation OpLoc, BinaryOperatorKind Opc,
                                 Expr *LHSExpr, Expr *RHSExpr);
 
   void DiagnoseCommaOperator(const Expr *LHS, SourceLocation Loc);
 
   /// ActOnConditionalOp - Parse a ?: operation.  Note that 'LHS' may be null
   /// in the case of a the GNU conditional expr extension.
   ExprResult ActOnConditionalOp(SourceLocation QuestionLoc,
                                 SourceLocation ColonLoc,
                                 Expr *CondExpr, Expr *LHSExpr, Expr *RHSExpr);
 
   /// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo".
   ExprResult ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc,
                             LabelDecl *TheDecl);
 
   void ActOnStartStmtExpr();
   ExprResult ActOnStmtExpr(Scope *S, SourceLocation LPLoc, Stmt *SubStmt,
                            SourceLocation RPLoc);
   ExprResult BuildStmtExpr(SourceLocation LPLoc, Stmt *SubStmt,
                            SourceLocation RPLoc, unsigned TemplateDepth);
   // Handle the final expression in a statement expression.
   ExprResult ActOnStmtExprResult(ExprResult E);
   void ActOnStmtExprError();
 
   // __builtin_offsetof(type, identifier(.identifier|[expr])*)
   struct OffsetOfComponent {
     SourceLocation LocStart, LocEnd;
     bool isBrackets;  // true if [expr], false if .ident
     union {
       IdentifierInfo *IdentInfo;
       Expr *E;
     } U;
   };
 
   /// __builtin_offsetof(type, a.b[123][456].c)
   ExprResult BuildBuiltinOffsetOf(SourceLocation BuiltinLoc,
                                   TypeSourceInfo *TInfo,
                                   ArrayRef<OffsetOfComponent> Components,
                                   SourceLocation RParenLoc);
   ExprResult ActOnBuiltinOffsetOf(Scope *S,
                                   SourceLocation BuiltinLoc,
                                   SourceLocation TypeLoc,
                                   ParsedType ParsedArgTy,
                                   ArrayRef<OffsetOfComponent> Components,
                                   SourceLocation RParenLoc);
 
   // __builtin_choose_expr(constExpr, expr1, expr2)
   ExprResult ActOnChooseExpr(SourceLocation BuiltinLoc,
                              Expr *CondExpr, Expr *LHSExpr,
                              Expr *RHSExpr, SourceLocation RPLoc);
 
   // __builtin_va_arg(expr, type)
   ExprResult ActOnVAArg(SourceLocation BuiltinLoc, Expr *E, ParsedType Ty,
                         SourceLocation RPLoc);
   ExprResult BuildVAArgExpr(SourceLocation BuiltinLoc, Expr *E,
                             TypeSourceInfo *TInfo, SourceLocation RPLoc);
 
   // __builtin_LINE(), __builtin_FUNCTION(), __builtin_FILE(),
   // __builtin_COLUMN()
   ExprResult ActOnSourceLocExpr(SourceLocExpr::IdentKind Kind,
                                 SourceLocation BuiltinLoc,
                                 SourceLocation RPLoc);
 
   // Build a potentially resolved SourceLocExpr.
   ExprResult BuildSourceLocExpr(SourceLocExpr::IdentKind Kind,
                                 SourceLocation BuiltinLoc, SourceLocation RPLoc,
                                 DeclContext *ParentContext);
 
   // __null
   ExprResult ActOnGNUNullExpr(SourceLocation TokenLoc);
 
   bool CheckCaseExpression(Expr *E);
 
   /// Describes the result of an "if-exists" condition check.
   enum IfExistsResult {
     /// The symbol exists.
     IER_Exists,
 
     /// The symbol does not exist.
     IER_DoesNotExist,
 
     /// The name is a dependent name, so the results will differ
     /// from one instantiation to the next.
     IER_Dependent,
 
     /// An error occurred.
     IER_Error
   };
 
   IfExistsResult
   CheckMicrosoftIfExistsSymbol(Scope *S, CXXScopeSpec &SS,
                                const DeclarationNameInfo &TargetNameInfo);
 
   IfExistsResult
   CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc,
                                bool IsIfExists, CXXScopeSpec &SS,
                                UnqualifiedId &Name);
 
   StmtResult BuildMSDependentExistsStmt(SourceLocation KeywordLoc,
                                         bool IsIfExists,
                                         NestedNameSpecifierLoc QualifierLoc,
                                         DeclarationNameInfo NameInfo,
                                         Stmt *Nested);
   StmtResult ActOnMSDependentExistsStmt(SourceLocation KeywordLoc,
                                         bool IsIfExists,
                                         CXXScopeSpec &SS, UnqualifiedId &Name,
                                         Stmt *Nested);
 
   //===------------------------- "Block" Extension ------------------------===//
 
   /// ActOnBlockStart - This callback is invoked when a block literal is
   /// started.
   void ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope);
 
   /// ActOnBlockArguments - This callback allows processing of block arguments.
   /// If there are no arguments, this is still invoked.
   void ActOnBlockArguments(SourceLocation CaretLoc, Declarator &ParamInfo,
                            Scope *CurScope);
 
   /// ActOnBlockError - If there is an error parsing a block, this callback
   /// is invoked to pop the information about the block from the action impl.
   void ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope);
 
   /// ActOnBlockStmtExpr - This is called when the body of a block statement
   /// literal was successfully completed.  ^(int x){...}
   ExprResult ActOnBlockStmtExpr(SourceLocation CaretLoc, Stmt *Body,
                                 Scope *CurScope);
 
   //===---------------------------- Clang Extensions ----------------------===//
 
   /// __builtin_convertvector(...)
   ExprResult ActOnConvertVectorExpr(Expr *E, ParsedType ParsedDestTy,
                                     SourceLocation BuiltinLoc,
                                     SourceLocation RParenLoc);
 
   //===---------------------------- OpenCL Features -----------------------===//
 
   /// __builtin_astype(...)
   ExprResult ActOnAsTypeExpr(Expr *E, ParsedType ParsedDestTy,
                              SourceLocation BuiltinLoc,
                              SourceLocation RParenLoc);
 
   //===---------------------------- C++ Features --------------------------===//
 
   // Act on C++ namespaces
   Decl *ActOnStartNamespaceDef(Scope *S, SourceLocation InlineLoc,
                                SourceLocation NamespaceLoc,
                                SourceLocation IdentLoc, IdentifierInfo *Ident,
                                SourceLocation LBrace,
                                const ParsedAttributesView &AttrList,
                                UsingDirectiveDecl *&UsingDecl);
   void ActOnFinishNamespaceDef(Decl *Dcl, SourceLocation RBrace);
 
   NamespaceDecl *getStdNamespace() const;
   NamespaceDecl *getOrCreateStdNamespace();
 
   NamespaceDecl *lookupStdExperimentalNamespace();
 
   CXXRecordDecl *getStdBadAlloc() const;
   EnumDecl *getStdAlignValT() const;
 
 private:
   // A cache representing if we've fully checked the various comparison category
   // types stored in ASTContext. The bit-index corresponds to the integer value
   // of a ComparisonCategoryType enumerator.
   llvm::SmallBitVector FullyCheckedComparisonCategories;
 
   ValueDecl *tryLookupCtorInitMemberDecl(CXXRecordDecl *ClassDecl,
                                          CXXScopeSpec &SS,
                                          ParsedType TemplateTypeTy,
                                          IdentifierInfo *MemberOrBase);
 
 public:
   enum class ComparisonCategoryUsage {
     /// The '<=>' operator was used in an expression and a builtin operator
     /// was selected.
     OperatorInExpression,
     /// A defaulted 'operator<=>' needed the comparison category. This
     /// typically only applies to 'std::strong_ordering', due to the implicit
     /// fallback return value.
     DefaultedOperator,
   };
 
   /// Lookup the specified comparison category types in the standard
   ///   library, an check the VarDecls possibly returned by the operator<=>
   ///   builtins for that type.
   ///
   /// \return The type of the comparison category type corresponding to the
   ///   specified Kind, or a null type if an error occurs
   QualType CheckComparisonCategoryType(ComparisonCategoryType Kind,
                                        SourceLocation Loc,
                                        ComparisonCategoryUsage Usage);
 
   /// Tests whether Ty is an instance of std::initializer_list and, if
   /// it is and Element is not NULL, assigns the element type to Element.
   bool isStdInitializerList(QualType Ty, QualType *Element);
 
   /// Looks for the std::initializer_list template and instantiates it
   /// with Element, or emits an error if it's not found.
   ///
   /// \returns The instantiated template, or null on error.
   QualType BuildStdInitializerList(QualType Element, SourceLocation Loc);
 
   /// Determine whether Ctor is an initializer-list constructor, as
   /// defined in [dcl.init.list]p2.
   bool isInitListConstructor(const FunctionDecl *Ctor);
 
   Decl *ActOnUsingDirective(Scope *CurScope, SourceLocation UsingLoc,
                             SourceLocation NamespcLoc, CXXScopeSpec &SS,
                             SourceLocation IdentLoc,
                             IdentifierInfo *NamespcName,
                             const ParsedAttributesView &AttrList);
 
   void PushUsingDirective(Scope *S, UsingDirectiveDecl *UDir);
 
   Decl *ActOnNamespaceAliasDef(Scope *CurScope,
                                SourceLocation NamespaceLoc,
                                SourceLocation AliasLoc,
                                IdentifierInfo *Alias,
                                CXXScopeSpec &SS,
                                SourceLocation IdentLoc,
                                IdentifierInfo *Ident);
 
   void HideUsingShadowDecl(Scope *S, UsingShadowDecl *Shadow);
   bool CheckUsingShadowDecl(UsingDecl *UD, NamedDecl *Target,
                             const LookupResult &PreviousDecls,
                             UsingShadowDecl *&PrevShadow);
   UsingShadowDecl *BuildUsingShadowDecl(Scope *S, UsingDecl *UD,
                                         NamedDecl *Target,
                                         UsingShadowDecl *PrevDecl);
 
   bool CheckUsingDeclRedeclaration(SourceLocation UsingLoc,
                                    bool HasTypenameKeyword,
                                    const CXXScopeSpec &SS,
                                    SourceLocation NameLoc,
                                    const LookupResult &Previous);
   bool CheckUsingDeclQualifier(SourceLocation UsingLoc,
                                bool HasTypename,
                                const CXXScopeSpec &SS,
                                const DeclarationNameInfo &NameInfo,
                                SourceLocation NameLoc);
 
   NamedDecl *BuildUsingDeclaration(
       Scope *S, AccessSpecifier AS, SourceLocation UsingLoc,
       bool HasTypenameKeyword, SourceLocation TypenameLoc, CXXScopeSpec &SS,
       DeclarationNameInfo NameInfo, SourceLocation EllipsisLoc,
       const ParsedAttributesView &AttrList, bool IsInstantiation);
   NamedDecl *BuildUsingPackDecl(NamedDecl *InstantiatedFrom,
                                 ArrayRef<NamedDecl *> Expansions);
 
   bool CheckInheritingConstructorUsingDecl(UsingDecl *UD);
 
   /// Given a derived-class using shadow declaration for a constructor and the
   /// correspnding base class constructor, find or create the implicit
   /// synthesized derived class constructor to use for this initialization.
   CXXConstructorDecl *
   findInheritingConstructor(SourceLocation Loc, CXXConstructorDecl *BaseCtor,
                             ConstructorUsingShadowDecl *DerivedShadow);
 
   Decl *ActOnUsingDeclaration(Scope *CurScope, AccessSpecifier AS,
                               SourceLocation UsingLoc,
                               SourceLocation TypenameLoc, CXXScopeSpec &SS,
                               UnqualifiedId &Name, SourceLocation EllipsisLoc,
                               const ParsedAttributesView &AttrList);
   Decl *ActOnAliasDeclaration(Scope *CurScope, AccessSpecifier AS,
                               MultiTemplateParamsArg TemplateParams,
                               SourceLocation UsingLoc, UnqualifiedId &Name,
                               const ParsedAttributesView &AttrList,
                               TypeResult Type, Decl *DeclFromDeclSpec);
 
   /// BuildCXXConstructExpr - Creates a complete call to a constructor,
   /// including handling of its default argument expressions.
   ///
   /// \param ConstructKind - a CXXConstructExpr::ConstructionKind
   ExprResult
   BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
                         NamedDecl *FoundDecl,
                         CXXConstructorDecl *Constructor, MultiExprArg Exprs,
                         bool HadMultipleCandidates, bool IsListInitialization,
                         bool IsStdInitListInitialization,
                         bool RequiresZeroInit, unsigned ConstructKind,
                         SourceRange ParenRange);
 
   /// Build a CXXConstructExpr whose constructor has already been resolved if
   /// it denotes an inherited constructor.
   ExprResult
   BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
                         CXXConstructorDecl *Constructor, bool Elidable,
                         MultiExprArg Exprs,
                         bool HadMultipleCandidates, bool IsListInitialization,
                         bool IsStdInitListInitialization,
                         bool RequiresZeroInit, unsigned ConstructKind,
                         SourceRange ParenRange);
 
   // FIXME: Can we remove this and have the above BuildCXXConstructExpr check if
   // the constructor can be elidable?
   ExprResult
   BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
                         NamedDecl *FoundDecl,
                         CXXConstructorDecl *Constructor, bool Elidable,
                         MultiExprArg Exprs, bool HadMultipleCandidates,
                         bool IsListInitialization,
                         bool IsStdInitListInitialization, bool RequiresZeroInit,
                         unsigned ConstructKind, SourceRange ParenRange);
 
   ExprResult BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field);
 
 
   /// Instantiate or parse a C++ default argument expression as necessary.
   /// Return true on error.
   bool CheckCXXDefaultArgExpr(SourceLocation CallLoc, FunctionDecl *FD,
                               ParmVarDecl *Param);
 
   /// BuildCXXDefaultArgExpr - Creates a CXXDefaultArgExpr, instantiating
   /// the default expr if needed.
   ExprResult BuildCXXDefaultArgExpr(SourceLocation CallLoc,
                                     FunctionDecl *FD,
                                     ParmVarDecl *Param);
 
   /// FinalizeVarWithDestructor - Prepare for calling destructor on the
   /// constructed variable.
   void FinalizeVarWithDestructor(VarDecl *VD, const RecordType *DeclInitType);
 
   /// Helper class that collects exception specifications for
   /// implicitly-declared special member functions.
   class ImplicitExceptionSpecification {
     // Pointer to allow copying
     Sema *Self;
     // We order exception specifications thus:
     // noexcept is the most restrictive, but is only used in C++11.
     // throw() comes next.
     // Then a throw(collected exceptions)
     // Finally no specification, which is expressed as noexcept(false).
     // throw(...) is used instead if any called function uses it.
     ExceptionSpecificationType ComputedEST;
     llvm::SmallPtrSet<CanQualType, 4> ExceptionsSeen;
     SmallVector<QualType, 4> Exceptions;
 
     void ClearExceptions() {
       ExceptionsSeen.clear();
       Exceptions.clear();
     }
 
   public:
     explicit ImplicitExceptionSpecification(Sema &Self)
       : Self(&Self), ComputedEST(EST_BasicNoexcept) {
       if (!Self.getLangOpts().CPlusPlus11)
         ComputedEST = EST_DynamicNone;
     }
 
     /// Get the computed exception specification type.
     ExceptionSpecificationType getExceptionSpecType() const {
       assert(!isComputedNoexcept(ComputedEST) &&
              "noexcept(expr) should not be a possible result");
       return ComputedEST;
     }
 
     /// The number of exceptions in the exception specification.
     unsigned size() const { return Exceptions.size(); }
 
     /// The set of exceptions in the exception specification.
     const QualType *data() const { return Exceptions.data(); }
 
     /// Integrate another called method into the collected data.
     void CalledDecl(SourceLocation CallLoc, const CXXMethodDecl *Method);
 
     /// Integrate an invoked expression into the collected data.
     void CalledExpr(Expr *E) { CalledStmt(E); }
 
     /// Integrate an invoked statement into the collected data.
     void CalledStmt(Stmt *S);
 
     /// Overwrite an EPI's exception specification with this
     /// computed exception specification.
     FunctionProtoType::ExceptionSpecInfo getExceptionSpec() const {
       FunctionProtoType::ExceptionSpecInfo ESI;
       ESI.Type = getExceptionSpecType();
       if (ESI.Type == EST_Dynamic) {
         ESI.Exceptions = Exceptions;
       } else if (ESI.Type == EST_None) {
         /// C++11 [except.spec]p14:
         ///   The exception-specification is noexcept(false) if the set of
         ///   potential exceptions of the special member function contains "any"
         ESI.Type = EST_NoexceptFalse;
         ESI.NoexceptExpr = Self->ActOnCXXBoolLiteral(SourceLocation(),
                                                      tok::kw_false).get();
       }
       return ESI;
     }
   };
 
   /// Determine what sort of exception specification a defaulted
   /// copy constructor of a class will have.
   ImplicitExceptionSpecification
   ComputeDefaultedDefaultCtorExceptionSpec(SourceLocation Loc,
                                            CXXMethodDecl *MD);
 
   /// Determine what sort of exception specification a defaulted
   /// default constructor of a class will have, and whether the parameter
   /// will be const.
   ImplicitExceptionSpecification
   ComputeDefaultedCopyCtorExceptionSpec(CXXMethodDecl *MD);
 
   /// Determine what sort of exception specification a defaulted
   /// copy assignment operator of a class will have, and whether the
   /// parameter will be const.
   ImplicitExceptionSpecification
   ComputeDefaultedCopyAssignmentExceptionSpec(CXXMethodDecl *MD);
 
   /// Determine what sort of exception specification a defaulted move
   /// constructor of a class will have.
   ImplicitExceptionSpecification
   ComputeDefaultedMoveCtorExceptionSpec(CXXMethodDecl *MD);
 
   /// Determine what sort of exception specification a defaulted move
   /// assignment operator of a class will have.
   ImplicitExceptionSpecification
   ComputeDefaultedMoveAssignmentExceptionSpec(CXXMethodDecl *MD);
 
   /// Determine what sort of exception specification a defaulted
   /// destructor of a class will have.
   ImplicitExceptionSpecification
   ComputeDefaultedDtorExceptionSpec(CXXMethodDecl *MD);
 
   /// Determine what sort of exception specification an inheriting
   /// constructor of a class will have.
   ImplicitExceptionSpecification
   ComputeInheritingCtorExceptionSpec(SourceLocation Loc,
                                      CXXConstructorDecl *CD);
 
   /// Evaluate the implicit exception specification for a defaulted
   /// special member function.
   void EvaluateImplicitExceptionSpec(SourceLocation Loc, FunctionDecl *FD);
 
   /// Check the given noexcept-specifier, convert its expression, and compute
   /// the appropriate ExceptionSpecificationType.
   ExprResult ActOnNoexceptSpec(SourceLocation NoexceptLoc, Expr *NoexceptExpr,
                                ExceptionSpecificationType &EST);
 
   /// Check the given exception-specification and update the
   /// exception specification information with the results.
   void checkExceptionSpecification(bool IsTopLevel,
                                    ExceptionSpecificationType EST,
                                    ArrayRef<ParsedType> DynamicExceptions,
                                    ArrayRef<SourceRange> DynamicExceptionRanges,
                                    Expr *NoexceptExpr,
                                    SmallVectorImpl<QualType> &Exceptions,
                                    FunctionProtoType::ExceptionSpecInfo &ESI);
 
   /// Determine if we're in a case where we need to (incorrectly) eagerly
   /// parse an exception specification to work around a libstdc++ bug.
   bool isLibstdcxxEagerExceptionSpecHack(const Declarator &D);
 
   /// Add an exception-specification to the given member function
   /// (or member function template). The exception-specification was parsed
   /// after the method itself was declared.
   void actOnDelayedExceptionSpecification(Decl *Method,
          ExceptionSpecificationType EST,
          SourceRange SpecificationRange,
          ArrayRef<ParsedType> DynamicExceptions,
          ArrayRef<SourceRange> DynamicExceptionRanges,
          Expr *NoexceptExpr);
 
   class InheritedConstructorInfo;
 
   /// Determine if a special member function should have a deleted
   /// definition when it is defaulted.
   bool ShouldDeleteSpecialMember(CXXMethodDecl *MD, CXXSpecialMember CSM,
                                  InheritedConstructorInfo *ICI = nullptr,
                                  bool Diagnose = false);
 
   /// Produce notes explaining why a defaulted function was defined as deleted.
   void DiagnoseDeletedDefaultedFunction(FunctionDecl *FD);
 
   /// Declare the implicit default constructor for the given class.
   ///
   /// \param ClassDecl The class declaration into which the implicit
   /// default constructor will be added.
   ///
   /// \returns The implicitly-declared default constructor.
   CXXConstructorDecl *DeclareImplicitDefaultConstructor(
                                                      CXXRecordDecl *ClassDecl);
 
   /// DefineImplicitDefaultConstructor - Checks for feasibility of
   /// defining this constructor as the default constructor.
   void DefineImplicitDefaultConstructor(SourceLocation CurrentLocation,
                                         CXXConstructorDecl *Constructor);
 
   /// Declare the implicit destructor for the given class.
   ///
   /// \param ClassDecl The class declaration into which the implicit
   /// destructor will be added.
   ///
   /// \returns The implicitly-declared destructor.
   CXXDestructorDecl *DeclareImplicitDestructor(CXXRecordDecl *ClassDecl);
 
   /// DefineImplicitDestructor - Checks for feasibility of
   /// defining this destructor as the default destructor.
   void DefineImplicitDestructor(SourceLocation CurrentLocation,
                                 CXXDestructorDecl *Destructor);
 
   /// Build an exception spec for destructors that don't have one.
   ///
   /// C++11 says that user-defined destructors with no exception spec get one
   /// that looks as if the destructor was implicitly declared.
   void AdjustDestructorExceptionSpec(CXXDestructorDecl *Destructor);
 
   /// Define the specified inheriting constructor.
   void DefineInheritingConstructor(SourceLocation UseLoc,
                                    CXXConstructorDecl *Constructor);
 
   /// Declare the implicit copy constructor for the given class.
   ///
   /// \param ClassDecl The class declaration into which the implicit
   /// copy constructor will be added.
   ///
   /// \returns The implicitly-declared copy constructor.
   CXXConstructorDecl *DeclareImplicitCopyConstructor(CXXRecordDecl *ClassDecl);
 
   /// DefineImplicitCopyConstructor - Checks for feasibility of
   /// defining this constructor as the copy constructor.
   void DefineImplicitCopyConstructor(SourceLocation CurrentLocation,
                                      CXXConstructorDecl *Constructor);
 
   /// Declare the implicit move constructor for the given class.
   ///
   /// \param ClassDecl The Class declaration into which the implicit
   /// move constructor will be added.
   ///
   /// \returns The implicitly-declared move constructor, or NULL if it wasn't
   /// declared.
   CXXConstructorDecl *DeclareImplicitMoveConstructor(CXXRecordDecl *ClassDecl);
 
   /// DefineImplicitMoveConstructor - Checks for feasibility of
   /// defining this constructor as the move constructor.
   void DefineImplicitMoveConstructor(SourceLocation CurrentLocation,
                                      CXXConstructorDecl *Constructor);
 
   /// Declare the implicit copy assignment operator for the given class.
   ///
   /// \param ClassDecl The class declaration into which the implicit
   /// copy assignment operator will be added.
   ///
   /// \returns The implicitly-declared copy assignment operator.
   CXXMethodDecl *DeclareImplicitCopyAssignment(CXXRecordDecl *ClassDecl);
 
   /// Defines an implicitly-declared copy assignment operator.
   void DefineImplicitCopyAssignment(SourceLocation CurrentLocation,
                                     CXXMethodDecl *MethodDecl);
 
   /// Declare the implicit move assignment operator for the given class.
   ///
   /// \param ClassDecl The Class declaration into which the implicit
   /// move assignment operator will be added.
   ///
   /// \returns The implicitly-declared move assignment operator, or NULL if it
   /// wasn't declared.
   CXXMethodDecl *DeclareImplicitMoveAssignment(CXXRecordDecl *ClassDecl);
 
   /// Defines an implicitly-declared move assignment operator.
   void DefineImplicitMoveAssignment(SourceLocation CurrentLocation,
                                     CXXMethodDecl *MethodDecl);
 
   /// Force the declaration of any implicitly-declared members of this
   /// class.
   void ForceDeclarationOfImplicitMembers(CXXRecordDecl *Class);
 
   /// Check a completed declaration of an implicit special member.
   void CheckImplicitSpecialMemberDeclaration(Scope *S, FunctionDecl *FD);
 
   /// Determine whether the given function is an implicitly-deleted
   /// special member function.
   bool isImplicitlyDeleted(FunctionDecl *FD);
 
   /// Check whether 'this' shows up in the type of a static member
   /// function after the (naturally empty) cv-qualifier-seq would be.
   ///
   /// \returns true if an error occurred.
   bool checkThisInStaticMemberFunctionType(CXXMethodDecl *Method);
 
   /// Whether this' shows up in the exception specification of a static
   /// member function.
   bool checkThisInStaticMemberFunctionExceptionSpec(CXXMethodDecl *Method);
 
   /// Check whether 'this' shows up in the attributes of the given
   /// static member function.
   ///
   /// \returns true if an error occurred.
   bool checkThisInStaticMemberFunctionAttributes(CXXMethodDecl *Method);
 
   /// MaybeBindToTemporary - If the passed in expression has a record type with
   /// a non-trivial destructor, this will return CXXBindTemporaryExpr. Otherwise
   /// it simply returns the passed in expression.
   ExprResult MaybeBindToTemporary(Expr *E);
 
   /// Wrap the expression in a ConstantExpr if it is a potential immediate
   /// invocation.
   ExprResult CheckForImmediateInvocation(ExprResult E, FunctionDecl *Decl);
 
   bool CompleteConstructorCall(CXXConstructorDecl *Constructor,
                                MultiExprArg ArgsPtr,
                                SourceLocation Loc,
                                SmallVectorImpl<Expr*> &ConvertedArgs,
                                bool AllowExplicit = false,
                                bool IsListInitialization = false);
 
   ParsedType getInheritingConstructorName(CXXScopeSpec &SS,
                                           SourceLocation NameLoc,
                                           IdentifierInfo &Name);
 
   ParsedType getConstructorName(IdentifierInfo &II, SourceLocation NameLoc,
                                 Scope *S, CXXScopeSpec &SS,
                                 bool EnteringContext);
   ParsedType getDestructorName(SourceLocation TildeLoc,
                                IdentifierInfo &II, SourceLocation NameLoc,
                                Scope *S, CXXScopeSpec &SS,
                                ParsedType ObjectType,
                                bool EnteringContext);
 
   ParsedType getDestructorTypeForDecltype(const DeclSpec &DS,
                                           ParsedType ObjectType);
 
   // Checks that reinterpret casts don't have undefined behavior.
   void CheckCompatibleReinterpretCast(QualType SrcType, QualType DestType,
                                       bool IsDereference, SourceRange Range);
 
   /// ActOnCXXNamedCast - Parse {dynamic,static,reinterpret,const}_cast's.
   ExprResult ActOnCXXNamedCast(SourceLocation OpLoc,
                                tok::TokenKind Kind,
                                SourceLocation LAngleBracketLoc,
                                Declarator &D,
                                SourceLocation RAngleBracketLoc,
                                SourceLocation LParenLoc,
                                Expr *E,
                                SourceLocation RParenLoc);
 
   ExprResult BuildCXXNamedCast(SourceLocation OpLoc,
                                tok::TokenKind Kind,
                                TypeSourceInfo *Ty,
                                Expr *E,
                                SourceRange AngleBrackets,
                                SourceRange Parens);
 
   ExprResult ActOnBuiltinBitCastExpr(SourceLocation KWLoc, Declarator &Dcl,
                                      ExprResult Operand,
                                      SourceLocation RParenLoc);
 
   ExprResult BuildBuiltinBitCastExpr(SourceLocation KWLoc, TypeSourceInfo *TSI,
                                      Expr *Operand, SourceLocation RParenLoc);
 
   ExprResult BuildCXXTypeId(QualType TypeInfoType,
                             SourceLocation TypeidLoc,
                             TypeSourceInfo *Operand,
                             SourceLocation RParenLoc);
   ExprResult BuildCXXTypeId(QualType TypeInfoType,
                             SourceLocation TypeidLoc,
                             Expr *Operand,
                             SourceLocation RParenLoc);
 
   /// ActOnCXXTypeid - Parse typeid( something ).
   ExprResult ActOnCXXTypeid(SourceLocation OpLoc,
                             SourceLocation LParenLoc, bool isType,
                             void *TyOrExpr,
                             SourceLocation RParenLoc);
 
   ExprResult BuildCXXUuidof(QualType TypeInfoType,
                             SourceLocation TypeidLoc,
                             TypeSourceInfo *Operand,
                             SourceLocation RParenLoc);
   ExprResult BuildCXXUuidof(QualType TypeInfoType,
                             SourceLocation TypeidLoc,
                             Expr *Operand,
                             SourceLocation RParenLoc);
 
   /// ActOnCXXUuidof - Parse __uuidof( something ).
   ExprResult ActOnCXXUuidof(SourceLocation OpLoc,
                             SourceLocation LParenLoc, bool isType,
                             void *TyOrExpr,
                             SourceLocation RParenLoc);
 
   /// Handle a C++1z fold-expression: ( expr op ... op expr ).
   ExprResult ActOnCXXFoldExpr(SourceLocation LParenLoc, Expr *LHS,
                               tok::TokenKind Operator,
                               SourceLocation EllipsisLoc, Expr *RHS,
                               SourceLocation RParenLoc);
   ExprResult BuildCXXFoldExpr(SourceLocation LParenLoc, Expr *LHS,
                               BinaryOperatorKind Operator,
                               SourceLocation EllipsisLoc, Expr *RHS,
                               SourceLocation RParenLoc,
                               Optional<unsigned> NumExpansions);
   ExprResult BuildEmptyCXXFoldExpr(SourceLocation EllipsisLoc,
                                    BinaryOperatorKind Operator);
 
   //// ActOnCXXThis -  Parse 'this' pointer.
   ExprResult ActOnCXXThis(SourceLocation loc);
 
   /// Build a CXXThisExpr and mark it referenced in the current context.
   Expr *BuildCXXThisExpr(SourceLocation Loc, QualType Type, bool IsImplicit);
   void MarkThisReferenced(CXXThisExpr *This);
 
   /// Try to retrieve the type of the 'this' pointer.
   ///
   /// \returns The type of 'this', if possible. Otherwise, returns a NULL type.
   QualType getCurrentThisType();
 
   /// When non-NULL, the C++ 'this' expression is allowed despite the
   /// current context not being a non-static member function. In such cases,
   /// this provides the type used for 'this'.
   QualType CXXThisTypeOverride;
 
   /// RAII object used to temporarily allow the C++ 'this' expression
   /// to be used, with the given qualifiers on the current class type.
   class CXXThisScopeRAII {
     Sema &S;
     QualType OldCXXThisTypeOverride;
     bool Enabled;
 
   public:
     /// Introduce a new scope where 'this' may be allowed (when enabled),
     /// using the given declaration (which is either a class template or a
     /// class) along with the given qualifiers.
     /// along with the qualifiers placed on '*this'.
     CXXThisScopeRAII(Sema &S, Decl *ContextDecl, Qualifiers CXXThisTypeQuals,
                      bool Enabled = true);
 
     ~CXXThisScopeRAII();
   };
 
   /// Make sure the value of 'this' is actually available in the current
   /// context, if it is a potentially evaluated context.
   ///
   /// \param Loc The location at which the capture of 'this' occurs.
   ///
   /// \param Explicit Whether 'this' is explicitly captured in a lambda
   /// capture list.
   ///
   /// \param FunctionScopeIndexToStopAt If non-null, it points to the index
   /// of the FunctionScopeInfo stack beyond which we do not attempt to capture.
   /// This is useful when enclosing lambdas must speculatively capture
   /// 'this' that may or may not be used in certain specializations of
   /// a nested generic lambda (depending on whether the name resolves to
   /// a non-static member function or a static function).
   /// \return returns 'true' if failed, 'false' if success.
   bool CheckCXXThisCapture(SourceLocation Loc, bool Explicit = false,
       bool BuildAndDiagnose = true,
       const unsigned *const FunctionScopeIndexToStopAt = nullptr,
       bool ByCopy = false);
 
   /// Determine whether the given type is the type of *this that is used
   /// outside of the body of a member function for a type that is currently
   /// being defined.
   bool isThisOutsideMemberFunctionBody(QualType BaseType);
 
   /// ActOnCXXBoolLiteral - Parse {true,false} literals.
   ExprResult ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind);
 
 
   /// ActOnObjCBoolLiteral - Parse {__objc_yes,__objc_no} literals.
   ExprResult ActOnObjCBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind);
 
   ExprResult
   ActOnObjCAvailabilityCheckExpr(llvm::ArrayRef<AvailabilitySpec> AvailSpecs,
                                  SourceLocation AtLoc, SourceLocation RParen);
 
   /// ActOnCXXNullPtrLiteral - Parse 'nullptr'.
   ExprResult ActOnCXXNullPtrLiteral(SourceLocation Loc);
 
   //// ActOnCXXThrow -  Parse throw expressions.
   ExprResult ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *expr);
   ExprResult BuildCXXThrow(SourceLocation OpLoc, Expr *Ex,
                            bool IsThrownVarInScope);
   bool CheckCXXThrowOperand(SourceLocation ThrowLoc, QualType ThrowTy, Expr *E);
 
   /// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
   /// Can be interpreted either as function-style casting ("int(x)")
   /// or class type construction ("ClassType(x,y,z)")
   /// or creation of a value-initialized type ("int()").
   ExprResult ActOnCXXTypeConstructExpr(ParsedType TypeRep,
                                        SourceLocation LParenOrBraceLoc,
                                        MultiExprArg Exprs,
                                        SourceLocation RParenOrBraceLoc,
                                        bool ListInitialization);
 
   ExprResult BuildCXXTypeConstructExpr(TypeSourceInfo *Type,
                                        SourceLocation LParenLoc,
                                        MultiExprArg Exprs,
                                        SourceLocation RParenLoc,
                                        bool ListInitialization);
 
   /// ActOnCXXNew - Parsed a C++ 'new' expression.
   ExprResult ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
                          SourceLocation PlacementLParen,
                          MultiExprArg PlacementArgs,
                          SourceLocation PlacementRParen,
                          SourceRange TypeIdParens, Declarator &D,
                          Expr *Initializer);
   ExprResult BuildCXXNew(SourceRange Range, bool UseGlobal,
                          SourceLocation PlacementLParen,
                          MultiExprArg PlacementArgs,
                          SourceLocation PlacementRParen,
                          SourceRange TypeIdParens,
                          QualType AllocType,
                          TypeSourceInfo *AllocTypeInfo,
                          Optional<Expr *> ArraySize,
                          SourceRange DirectInitRange,
                          Expr *Initializer);
 
   /// Determine whether \p FD is an aligned allocation or deallocation
   /// function that is unavailable.
   bool isUnavailableAlignedAllocationFunction(const FunctionDecl &FD) const;
 
   /// Produce diagnostics if \p FD is an aligned allocation or deallocation
   /// function that is unavailable.
   void diagnoseUnavailableAlignedAllocation(const FunctionDecl &FD,
                                             SourceLocation Loc);
 
   bool CheckAllocatedType(QualType AllocType, SourceLocation Loc,
                           SourceRange R);
 
   /// The scope in which to find allocation functions.
   enum AllocationFunctionScope {
     /// Only look for allocation functions in the global scope.
     AFS_Global,
     /// Only look for allocation functions in the scope of the
     /// allocated class.
     AFS_Class,
     /// Look for allocation functions in both the global scope
     /// and in the scope of the allocated class.
     AFS_Both
   };
 
   /// Finds the overloads of operator new and delete that are appropriate
   /// for the allocation.
   bool FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
                                AllocationFunctionScope NewScope,
                                AllocationFunctionScope DeleteScope,
                                QualType AllocType, bool IsArray,
                                bool &PassAlignment, MultiExprArg PlaceArgs,
                                FunctionDecl *&OperatorNew,
                                FunctionDecl *&OperatorDelete,
                                bool Diagnose = true);
   void DeclareGlobalNewDelete();
   void DeclareGlobalAllocationFunction(DeclarationName Name, QualType Return,
                                        ArrayRef<QualType> Params);
 
   bool FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD,
                                 DeclarationName Name, FunctionDecl* &Operator,
                                 bool Diagnose = true);
   FunctionDecl *FindUsualDeallocationFunction(SourceLocation StartLoc,
                                               bool CanProvideSize,
                                               bool Overaligned,
                                               DeclarationName Name);
   FunctionDecl *FindDeallocationFunctionForDestructor(SourceLocation StartLoc,
                                                       CXXRecordDecl *RD);
 
   /// ActOnCXXDelete - Parsed a C++ 'delete' expression
   ExprResult ActOnCXXDelete(SourceLocation StartLoc,
                             bool UseGlobal, bool ArrayForm,
                             Expr *Operand);
   void CheckVirtualDtorCall(CXXDestructorDecl *dtor, SourceLocation Loc,
                             bool IsDelete, bool CallCanBeVirtual,
                             bool WarnOnNonAbstractTypes,
                             SourceLocation DtorLoc);
 
   ExprResult ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation LParen,
                                Expr *Operand, SourceLocation RParen);
   ExprResult BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand,
                                   SourceLocation RParen);
 
   /// Parsed one of the type trait support pseudo-functions.
   ExprResult ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
                             ArrayRef<ParsedType> Args,
                             SourceLocation RParenLoc);
   ExprResult BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
                             ArrayRef<TypeSourceInfo *> Args,
                             SourceLocation RParenLoc);
 
   /// ActOnArrayTypeTrait - Parsed one of the binary type trait support
   /// pseudo-functions.
   ExprResult ActOnArrayTypeTrait(ArrayTypeTrait ATT,
                                  SourceLocation KWLoc,
                                  ParsedType LhsTy,
                                  Expr *DimExpr,
                                  SourceLocation RParen);
 
   ExprResult BuildArrayTypeTrait(ArrayTypeTrait ATT,
                                  SourceLocation KWLoc,
                                  TypeSourceInfo *TSInfo,
                                  Expr *DimExpr,
                                  SourceLocation RParen);
 
   /// ActOnExpressionTrait - Parsed one of the unary type trait support
   /// pseudo-functions.
   ExprResult ActOnExpressionTrait(ExpressionTrait OET,
                                   SourceLocation KWLoc,
                                   Expr *Queried,
                                   SourceLocation RParen);
 
   ExprResult BuildExpressionTrait(ExpressionTrait OET,
                                   SourceLocation KWLoc,
                                   Expr *Queried,
                                   SourceLocation RParen);
 
   ExprResult ActOnStartCXXMemberReference(Scope *S,
                                           Expr *Base,
                                           SourceLocation OpLoc,
                                           tok::TokenKind OpKind,
                                           ParsedType &ObjectType,
                                           bool &MayBePseudoDestructor);
 
   ExprResult BuildPseudoDestructorExpr(Expr *Base,
                                        SourceLocation OpLoc,
                                        tok::TokenKind OpKind,
                                        const CXXScopeSpec &SS,
                                        TypeSourceInfo *ScopeType,
                                        SourceLocation CCLoc,
                                        SourceLocation TildeLoc,
                                      PseudoDestructorTypeStorage DestroyedType);
 
   ExprResult ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
                                        SourceLocation OpLoc,
                                        tok::TokenKind OpKind,
                                        CXXScopeSpec &SS,
                                        UnqualifiedId &FirstTypeName,
                                        SourceLocation CCLoc,
                                        SourceLocation TildeLoc,
                                        UnqualifiedId &SecondTypeName);
 
   ExprResult ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
                                        SourceLocation OpLoc,
                                        tok::TokenKind OpKind,
                                        SourceLocation TildeLoc,
                                        const DeclSpec& DS);
 
   /// MaybeCreateExprWithCleanups - If the current full-expression
   /// requires any cleanups, surround it with a ExprWithCleanups node.
   /// Otherwise, just returns the passed-in expression.
   Expr *MaybeCreateExprWithCleanups(Expr *SubExpr);
   Stmt *MaybeCreateStmtWithCleanups(Stmt *SubStmt);
   ExprResult MaybeCreateExprWithCleanups(ExprResult SubExpr);
 
   MaterializeTemporaryExpr *
   CreateMaterializeTemporaryExpr(QualType T, Expr *Temporary,
                                  bool BoundToLvalueReference);
 
   ExprResult ActOnFinishFullExpr(Expr *Expr, bool DiscardedValue) {
     return ActOnFinishFullExpr(
         Expr, Expr ? Expr->getExprLoc() : SourceLocation(), DiscardedValue);
   }
   ExprResult ActOnFinishFullExpr(Expr *Expr, SourceLocation CC,
                                  bool DiscardedValue, bool IsConstexpr = false);
   StmtResult ActOnFinishFullStmt(Stmt *Stmt);
 
   // Marks SS invalid if it represents an incomplete type.
   bool RequireCompleteDeclContext(CXXScopeSpec &SS, DeclContext *DC);
 
   DeclContext *computeDeclContext(QualType T);
   DeclContext *computeDeclContext(const CXXScopeSpec &SS,
                                   bool EnteringContext = false);
   bool isDependentScopeSpecifier(const CXXScopeSpec &SS);
   CXXRecordDecl *getCurrentInstantiationOf(NestedNameSpecifier *NNS);
 
   /// The parser has parsed a global nested-name-specifier '::'.
   ///
   /// \param CCLoc The location of the '::'.
   ///
   /// \param SS The nested-name-specifier, which will be updated in-place
   /// to reflect the parsed nested-name-specifier.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool ActOnCXXGlobalScopeSpecifier(SourceLocation CCLoc, CXXScopeSpec &SS);
 
   /// The parser has parsed a '__super' nested-name-specifier.
   ///
   /// \param SuperLoc The location of the '__super' keyword.
   ///
   /// \param ColonColonLoc The location of the '::'.
   ///
   /// \param SS The nested-name-specifier, which will be updated in-place
   /// to reflect the parsed nested-name-specifier.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool ActOnSuperScopeSpecifier(SourceLocation SuperLoc,
                                 SourceLocation ColonColonLoc, CXXScopeSpec &SS);
 
   bool isAcceptableNestedNameSpecifier(const NamedDecl *SD,
                                        bool *CanCorrect = nullptr);
   NamedDecl *FindFirstQualifierInScope(Scope *S, NestedNameSpecifier *NNS);
 
   /// Keeps information about an identifier in a nested-name-spec.
   ///
   struct NestedNameSpecInfo {
     /// The type of the object, if we're parsing nested-name-specifier in
     /// a member access expression.
     ParsedType ObjectType;
 
     /// The identifier preceding the '::'.
     IdentifierInfo *Identifier;
 
     /// The location of the identifier.
     SourceLocation IdentifierLoc;
 
     /// The location of the '::'.
     SourceLocation CCLoc;
 
     /// Creates info object for the most typical case.
     NestedNameSpecInfo(IdentifierInfo *II, SourceLocation IdLoc,
              SourceLocation ColonColonLoc, ParsedType ObjectType = ParsedType())
       : ObjectType(ObjectType), Identifier(II), IdentifierLoc(IdLoc),
         CCLoc(ColonColonLoc) {
     }
 
     NestedNameSpecInfo(IdentifierInfo *II, SourceLocation IdLoc,
                        SourceLocation ColonColonLoc, QualType ObjectType)
       : ObjectType(ParsedType::make(ObjectType)), Identifier(II),
         IdentifierLoc(IdLoc), CCLoc(ColonColonLoc) {
     }
   };
 
   bool isNonTypeNestedNameSpecifier(Scope *S, CXXScopeSpec &SS,
                                     NestedNameSpecInfo &IdInfo);
 
   bool BuildCXXNestedNameSpecifier(Scope *S,
                                    NestedNameSpecInfo &IdInfo,
                                    bool EnteringContext,
                                    CXXScopeSpec &SS,
                                    NamedDecl *ScopeLookupResult,
                                    bool ErrorRecoveryLookup,
                                    bool *IsCorrectedToColon = nullptr,
                                    bool OnlyNamespace = false);
 
   /// The parser has parsed a nested-name-specifier 'identifier::'.
   ///
   /// \param S The scope in which this nested-name-specifier occurs.
   ///
   /// \param IdInfo Parser information about an identifier in the
   /// nested-name-spec.
   ///
   /// \param EnteringContext Whether we're entering the context nominated by
   /// this nested-name-specifier.
   ///
   /// \param SS The nested-name-specifier, which is both an input
   /// parameter (the nested-name-specifier before this type) and an
   /// output parameter (containing the full nested-name-specifier,
   /// including this new type).
   ///
   /// \param ErrorRecoveryLookup If true, then this method is called to improve
   /// error recovery. In this case do not emit error message.
   ///
   /// \param IsCorrectedToColon If not null, suggestions to replace '::' -> ':'
   /// are allowed.  The bool value pointed by this parameter is set to 'true'
   /// if the identifier is treated as if it was followed by ':', not '::'.
   ///
   /// \param OnlyNamespace If true, only considers namespaces in lookup.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool ActOnCXXNestedNameSpecifier(Scope *S,
                                    NestedNameSpecInfo &IdInfo,
                                    bool EnteringContext,
                                    CXXScopeSpec &SS,
                                    bool ErrorRecoveryLookup = false,
                                    bool *IsCorrectedToColon = nullptr,
                                    bool OnlyNamespace = false);
 
   ExprResult ActOnDecltypeExpression(Expr *E);
 
   bool ActOnCXXNestedNameSpecifierDecltype(CXXScopeSpec &SS,
                                            const DeclSpec &DS,
                                            SourceLocation ColonColonLoc);
 
   bool IsInvalidUnlessNestedName(Scope *S, CXXScopeSpec &SS,
                                  NestedNameSpecInfo &IdInfo,
                                  bool EnteringContext);
 
   /// The parser has parsed a nested-name-specifier
   /// 'template[opt] template-name < template-args >::'.
   ///
   /// \param S The scope in which this nested-name-specifier occurs.
   ///
   /// \param SS The nested-name-specifier, which is both an input
   /// parameter (the nested-name-specifier before this type) and an
   /// output parameter (containing the full nested-name-specifier,
   /// including this new type).
   ///
   /// \param TemplateKWLoc the location of the 'template' keyword, if any.
   /// \param TemplateName the template name.
   /// \param TemplateNameLoc The location of the template name.
   /// \param LAngleLoc The location of the opening angle bracket  ('<').
   /// \param TemplateArgs The template arguments.
   /// \param RAngleLoc The location of the closing angle bracket  ('>').
   /// \param CCLoc The location of the '::'.
   ///
   /// \param EnteringContext Whether we're entering the context of the
   /// nested-name-specifier.
   ///
   ///
   /// \returns true if an error occurred, false otherwise.
   bool ActOnCXXNestedNameSpecifier(Scope *S,
                                    CXXScopeSpec &SS,
                                    SourceLocation TemplateKWLoc,
                                    TemplateTy TemplateName,
                                    SourceLocation TemplateNameLoc,
                                    SourceLocation LAngleLoc,
                                    ASTTemplateArgsPtr TemplateArgs,
                                    SourceLocation RAngleLoc,
                                    SourceLocation CCLoc,
                                    bool EnteringContext);
 
   /// Given a C++ nested-name-specifier, produce an annotation value
   /// that the parser can use later to reconstruct the given
   /// nested-name-specifier.
   ///
   /// \param SS A nested-name-specifier.
   ///
   /// \returns A pointer containing all of the information in the
   /// nested-name-specifier \p SS.
   void *SaveNestedNameSpecifierAnnotation(CXXScopeSpec &SS);
 
   /// Given an annotation pointer for a nested-name-specifier, restore
   /// the nested-name-specifier structure.
   ///
   /// \param Annotation The annotation pointer, produced by
   /// \c SaveNestedNameSpecifierAnnotation().
   ///
   /// \param AnnotationRange The source range corresponding to the annotation.
   ///
   /// \param SS The nested-name-specifier that will be updated with the contents
   /// of the annotation pointer.
   void RestoreNestedNameSpecifierAnnotation(void *Annotation,
                                             SourceRange AnnotationRange,
                                             CXXScopeSpec &SS);
 
   bool ShouldEnterDeclaratorScope(Scope *S, const CXXScopeSpec &SS);
 
   /// ActOnCXXEnterDeclaratorScope - Called when a C++ scope specifier (global
   /// scope or nested-name-specifier) is parsed, part of a declarator-id.
   /// After this method is called, according to [C++ 3.4.3p3], names should be
   /// looked up in the declarator-id's scope, until the declarator is parsed and
   /// ActOnCXXExitDeclaratorScope is called.
   /// The 'SS' should be a non-empty valid CXXScopeSpec.
   bool ActOnCXXEnterDeclaratorScope(Scope *S, CXXScopeSpec &SS);
 
   /// ActOnCXXExitDeclaratorScope - Called when a declarator that previously
   /// invoked ActOnCXXEnterDeclaratorScope(), is finished. 'SS' is the same
   /// CXXScopeSpec that was passed to ActOnCXXEnterDeclaratorScope as well.
   /// Used to indicate that names should revert to being looked up in the
   /// defining scope.
   void ActOnCXXExitDeclaratorScope(Scope *S, const CXXScopeSpec &SS);
 
   /// ActOnCXXEnterDeclInitializer - Invoked when we are about to parse an
   /// initializer for the declaration 'Dcl'.
   /// After this method is called, according to [C++ 3.4.1p13], if 'Dcl' is a
   /// static data member of class X, names should be looked up in the scope of
   /// class X.
   void ActOnCXXEnterDeclInitializer(Scope *S, Decl *Dcl);
 
   /// ActOnCXXExitDeclInitializer - Invoked after we are finished parsing an
   /// initializer for the declaration 'Dcl'.
   void ActOnCXXExitDeclInitializer(Scope *S, Decl *Dcl);
 
   /// Create a new lambda closure type.
   CXXRecordDecl *createLambdaClosureType(SourceRange IntroducerRange,
                                          TypeSourceInfo *Info,
                                          bool KnownDependent,
                                          LambdaCaptureDefault CaptureDefault);
 
   /// Start the definition of a lambda expression.
   CXXMethodDecl *startLambdaDefinition(CXXRecordDecl *Class,
                                        SourceRange IntroducerRange,
                                        TypeSourceInfo *MethodType,
                                        SourceLocation EndLoc,
                                        ArrayRef<ParmVarDecl *> Params,
                                        ConstexprSpecKind ConstexprKind,
                                        Expr *TrailingRequiresClause);
 
   /// Number lambda for linkage purposes if necessary.
   void handleLambdaNumbering(
       CXXRecordDecl *Class, CXXMethodDecl *Method,
       Optional<std::tuple<unsigned, bool, Decl *>> Mangling = None);
 
   /// Endow the lambda scope info with the relevant properties.
   void buildLambdaScope(sema::LambdaScopeInfo *LSI,
                         CXXMethodDecl *CallOperator,
                         SourceRange IntroducerRange,
                         LambdaCaptureDefault CaptureDefault,
                         SourceLocation CaptureDefaultLoc,
                         bool ExplicitParams,
                         bool ExplicitResultType,
                         bool Mutable);
 
   /// Perform initialization analysis of the init-capture and perform
   /// any implicit conversions such as an lvalue-to-rvalue conversion if
   /// not being used to initialize a reference.
   ParsedType actOnLambdaInitCaptureInitialization(
       SourceLocation Loc, bool ByRef, SourceLocation EllipsisLoc,
       IdentifierInfo *Id, LambdaCaptureInitKind InitKind, Expr *&Init) {
     return ParsedType::make(buildLambdaInitCaptureInitialization(
         Loc, ByRef, EllipsisLoc, None, Id,
         InitKind != LambdaCaptureInitKind::CopyInit, Init));
   }
   QualType buildLambdaInitCaptureInitialization(
       SourceLocation Loc, bool ByRef, SourceLocation EllipsisLoc,
       Optional<unsigned> NumExpansions, IdentifierInfo *Id, bool DirectInit,
       Expr *&Init);
 
   /// Create a dummy variable within the declcontext of the lambda's
   ///  call operator, for name lookup purposes for a lambda init capture.
   ///
   ///  CodeGen handles emission of lambda captures, ignoring these dummy
   ///  variables appropriately.
   VarDecl *createLambdaInitCaptureVarDecl(SourceLocation Loc,
                                           QualType InitCaptureType,
                                           SourceLocation EllipsisLoc,
                                           IdentifierInfo *Id,
                                           unsigned InitStyle, Expr *Init);
 
   /// Add an init-capture to a lambda scope.
   void addInitCapture(sema::LambdaScopeInfo *LSI, VarDecl *Var);
 
   /// Note that we have finished the explicit captures for the
   /// given lambda.
   void finishLambdaExplicitCaptures(sema::LambdaScopeInfo *LSI);
 
   /// \brief This is called after parsing the explicit template parameter list
   /// on a lambda (if it exists) in C++2a.
   void ActOnLambdaExplicitTemplateParameterList(SourceLocation LAngleLoc,
                                                 ArrayRef<NamedDecl *> TParams,
                                                 SourceLocation RAngleLoc);
 
   /// Introduce the lambda parameters into scope.
   void addLambdaParameters(
       ArrayRef<LambdaIntroducer::LambdaCapture> Captures,
       CXXMethodDecl *CallOperator, Scope *CurScope);
 
   /// Deduce a block or lambda's return type based on the return
   /// statements present in the body.
   void deduceClosureReturnType(sema::CapturingScopeInfo &CSI);
 
   /// ActOnStartOfLambdaDefinition - This is called just before we start
   /// parsing the body of a lambda; it analyzes the explicit captures and
   /// arguments, and sets up various data-structures for the body of the
   /// lambda.
   void ActOnStartOfLambdaDefinition(LambdaIntroducer &Intro,
                                     Declarator &ParamInfo, Scope *CurScope);
 
   /// ActOnLambdaError - If there is an error parsing a lambda, this callback
   /// is invoked to pop the information about the lambda.
   void ActOnLambdaError(SourceLocation StartLoc, Scope *CurScope,
                         bool IsInstantiation = false);
 
   /// ActOnLambdaExpr - This is called when the body of a lambda expression
   /// was successfully completed.
   ExprResult ActOnLambdaExpr(SourceLocation StartLoc, Stmt *Body,
                              Scope *CurScope);
 
   /// Does copying/destroying the captured variable have side effects?
   bool CaptureHasSideEffects(const sema::Capture &From);
 
   /// Diagnose if an explicit lambda capture is unused. Returns true if a
   /// diagnostic is emitted.
   bool DiagnoseUnusedLambdaCapture(SourceRange CaptureRange,
                                    const sema::Capture &From);
 
   /// Build a FieldDecl suitable to hold the given capture.
   FieldDecl *BuildCaptureField(RecordDecl *RD, const sema::Capture &Capture);
 
   /// Initialize the given capture with a suitable expression.
   ExprResult BuildCaptureInit(const sema::Capture &Capture,
                               SourceLocation ImplicitCaptureLoc,
                               bool IsOpenMPMapping = false);
 
   /// Complete a lambda-expression having processed and attached the
   /// lambda body.
   ExprResult BuildLambdaExpr(SourceLocation StartLoc, SourceLocation EndLoc,
                              sema::LambdaScopeInfo *LSI);
 
   /// Get the return type to use for a lambda's conversion function(s) to
   /// function pointer type, given the type of the call operator.
   QualType
   getLambdaConversionFunctionResultType(const FunctionProtoType *CallOpType);
 
   /// Define the "body" of the conversion from a lambda object to a
   /// function pointer.
   ///
   /// This routine doesn't actually define a sensible body; rather, it fills
   /// in the initialization expression needed to copy the lambda object into
   /// the block, and IR generation actually generates the real body of the
   /// block pointer conversion.
   void DefineImplicitLambdaToFunctionPointerConversion(
          SourceLocation CurrentLoc, CXXConversionDecl *Conv);
 
   /// Define the "body" of the conversion from a lambda object to a
   /// block pointer.
   ///
   /// This routine doesn't actually define a sensible body; rather, it fills
   /// in the initialization expression needed to copy the lambda object into
   /// the block, and IR generation actually generates the real body of the
   /// block pointer conversion.
   void DefineImplicitLambdaToBlockPointerConversion(SourceLocation CurrentLoc,
                                                     CXXConversionDecl *Conv);
 
   ExprResult BuildBlockForLambdaConversion(SourceLocation CurrentLocation,
                                            SourceLocation ConvLocation,
                                            CXXConversionDecl *Conv,
                                            Expr *Src);
 
   /// Check whether the given expression is a valid constraint expression.
   /// A diagnostic is emitted if it is not, false is returned, and
   /// PossibleNonPrimary will be set to true if the failure might be due to a
   /// non-primary expression being used as an atomic constraint.
   bool CheckConstraintExpression(Expr *CE, Token NextToken = Token(),
                                  bool *PossibleNonPrimary = nullptr,
                                  bool IsTrailingRequiresClause = false);
 
   /// Check whether the given type-dependent expression will be the name of a
   /// function or another callable function-like entity (e.g. a function
   // template or overload set) for any substitution.
   bool IsDependentFunctionNameExpr(Expr *E);
 
 private:
   /// Caches pairs of template-like decls whose associated constraints were
   /// checked for subsumption and whether or not the first's constraints did in
   /// fact subsume the second's.
   llvm::DenseMap<std::pair<NamedDecl *, NamedDecl *>, bool> SubsumptionCache;
   /// Caches the normalized associated constraints of declarations (concepts or
   /// constrained declarations). If an error occurred while normalizing the
   /// associated constraints of the template or concept, nullptr will be cached
   /// here.
   llvm::DenseMap<NamedDecl *, NormalizedConstraint *>
       NormalizationCache;
 
   llvm::ContextualFoldingSet<ConstraintSatisfaction, const ASTContext &>
       SatisfactionCache;
 
 public:
   const NormalizedConstraint *
   getNormalizedAssociatedConstraints(
       NamedDecl *ConstrainedDecl, ArrayRef<const Expr *> AssociatedConstraints);
 
   /// \brief Check whether the given declaration's associated constraints are
   /// at least as constrained than another declaration's according to the
   /// partial ordering of constraints.
   ///
   /// \param Result If no error occurred, receives the result of true if D1 is
   /// at least constrained than D2, and false otherwise.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool IsAtLeastAsConstrained(NamedDecl *D1, ArrayRef<const Expr *> AC1,
                               NamedDecl *D2, ArrayRef<const Expr *> AC2,
                               bool &Result);
 
   /// If D1 was not at least as constrained as D2, but would've been if a pair
   /// of atomic constraints involved had been declared in a concept and not
   /// repeated in two separate places in code.
   /// \returns true if such a diagnostic was emitted, false otherwise.
   bool MaybeEmitAmbiguousAtomicConstraintsDiagnostic(NamedDecl *D1,
       ArrayRef<const Expr *> AC1, NamedDecl *D2, ArrayRef<const Expr *> AC2);
 
   /// \brief Check whether the given list of constraint expressions are
   /// satisfied (as if in a 'conjunction') given template arguments.
   /// \param Template the template-like entity that triggered the constraints
   /// check (either a concept or a constrained entity).
   /// \param ConstraintExprs a list of constraint expressions, treated as if
   /// they were 'AND'ed together.
   /// \param TemplateArgs the list of template arguments to substitute into the
   /// constraint expression.
   /// \param TemplateIDRange The source range of the template id that
   /// caused the constraints check.
   /// \param Satisfaction if true is returned, will contain details of the
   /// satisfaction, with enough information to diagnose an unsatisfied
   /// expression.
   /// \returns true if an error occurred and satisfaction could not be checked,
   /// false otherwise.
   bool CheckConstraintSatisfaction(
       const NamedDecl *Template, ArrayRef<const Expr *> ConstraintExprs,
       ArrayRef<TemplateArgument> TemplateArgs,
       SourceRange TemplateIDRange, ConstraintSatisfaction &Satisfaction);
 
   /// \brief Check whether the given non-dependent constraint expression is
   /// satisfied. Returns false and updates Satisfaction with the satisfaction
   /// verdict if successful, emits a diagnostic and returns true if an error
   /// occured and satisfaction could not be determined.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool CheckConstraintSatisfaction(const Expr *ConstraintExpr,
                                    ConstraintSatisfaction &Satisfaction);
 
   /// Check whether the given function decl's trailing requires clause is
   /// satisfied, if any. Returns false and updates Satisfaction with the
   /// satisfaction verdict if successful, emits a diagnostic and returns true if
   /// an error occured and satisfaction could not be determined.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool CheckFunctionConstraints(const FunctionDecl *FD,
                                 ConstraintSatisfaction &Satisfaction,
                                 SourceLocation UsageLoc = SourceLocation());
 
 
   /// \brief Ensure that the given template arguments satisfy the constraints
   /// associated with the given template, emitting a diagnostic if they do not.
   ///
   /// \param Template The template to which the template arguments are being
   /// provided.
   ///
   /// \param TemplateArgs The converted, canonicalized template arguments.
   ///
   /// \param TemplateIDRange The source range of the template id that
   /// caused the constraints check.
   ///
   /// \returns true if the constrains are not satisfied or could not be checked
   /// for satisfaction, false if the constraints are satisfied.
   bool EnsureTemplateArgumentListConstraints(TemplateDecl *Template,
                                        ArrayRef<TemplateArgument> TemplateArgs,
                                              SourceRange TemplateIDRange);
 
   /// \brief Emit diagnostics explaining why a constraint expression was deemed
   /// unsatisfied.
   /// \param First whether this is the first time an unsatisfied constraint is
   /// diagnosed for this error.
   void
   DiagnoseUnsatisfiedConstraint(const ConstraintSatisfaction &Satisfaction,
                                 bool First = true);
 
   /// \brief Emit diagnostics explaining why a constraint expression was deemed
   /// unsatisfied.
   void
   DiagnoseUnsatisfiedConstraint(const ASTConstraintSatisfaction &Satisfaction,
                                 bool First = true);
 
   /// \brief Emit diagnostics explaining why a constraint expression was deemed
   /// unsatisfied because it was ill-formed.
   void DiagnoseUnsatisfiedIllFormedConstraint(SourceLocation DiagnosticLocation,
                                               StringRef Diagnostic);
 
   void DiagnoseRedeclarationConstraintMismatch(SourceLocation Old,
                                                SourceLocation New);
 
   // ParseObjCStringLiteral - Parse Objective-C string literals.
   ExprResult ParseObjCStringLiteral(SourceLocation *AtLocs,
                                     ArrayRef<Expr *> Strings);
 
   ExprResult BuildObjCStringLiteral(SourceLocation AtLoc, StringLiteral *S);
 
   /// BuildObjCNumericLiteral - builds an ObjCBoxedExpr AST node for the
   /// numeric literal expression. Type of the expression will be "NSNumber *"
   /// or "id" if NSNumber is unavailable.
   ExprResult BuildObjCNumericLiteral(SourceLocation AtLoc, Expr *Number);
   ExprResult ActOnObjCBoolLiteral(SourceLocation AtLoc, SourceLocation ValueLoc,
                                   bool Value);
   ExprResult BuildObjCArrayLiteral(SourceRange SR, MultiExprArg Elements);
 
   /// BuildObjCBoxedExpr - builds an ObjCBoxedExpr AST node for the
   /// '@' prefixed parenthesized expression. The type of the expression will
   /// either be "NSNumber *", "NSString *" or "NSValue *" depending on the type
   /// of ValueType, which is allowed to be a built-in numeric type, "char *",
   /// "const char *" or C structure with attribute 'objc_boxable'.
   ExprResult BuildObjCBoxedExpr(SourceRange SR, Expr *ValueExpr);
 
   ExprResult BuildObjCSubscriptExpression(SourceLocation RB, Expr *BaseExpr,
                                           Expr *IndexExpr,
                                           ObjCMethodDecl *getterMethod,
                                           ObjCMethodDecl *setterMethod);
 
   ExprResult BuildObjCDictionaryLiteral(SourceRange SR,
                                MutableArrayRef<ObjCDictionaryElement> Elements);
 
   ExprResult BuildObjCEncodeExpression(SourceLocation AtLoc,
                                   TypeSourceInfo *EncodedTypeInfo,
                                   SourceLocation RParenLoc);
   ExprResult BuildCXXMemberCallExpr(Expr *Exp, NamedDecl *FoundDecl,
                                     CXXConversionDecl *Method,
                                     bool HadMultipleCandidates);
 
   ExprResult ParseObjCEncodeExpression(SourceLocation AtLoc,
                                        SourceLocation EncodeLoc,
                                        SourceLocation LParenLoc,
                                        ParsedType Ty,
                                        SourceLocation RParenLoc);
 
   /// ParseObjCSelectorExpression - Build selector expression for \@selector
   ExprResult ParseObjCSelectorExpression(Selector Sel,
                                          SourceLocation AtLoc,
                                          SourceLocation SelLoc,
                                          SourceLocation LParenLoc,
                                          SourceLocation RParenLoc,
                                          bool WarnMultipleSelectors);
 
   /// ParseObjCProtocolExpression - Build protocol expression for \@protocol
   ExprResult ParseObjCProtocolExpression(IdentifierInfo * ProtocolName,
                                          SourceLocation AtLoc,
                                          SourceLocation ProtoLoc,
                                          SourceLocation LParenLoc,
                                          SourceLocation ProtoIdLoc,
                                          SourceLocation RParenLoc);
 
   //===--------------------------------------------------------------------===//
   // C++ Declarations
   //
   Decl *ActOnStartLinkageSpecification(Scope *S,
                                        SourceLocation ExternLoc,
                                        Expr *LangStr,
                                        SourceLocation LBraceLoc);
   Decl *ActOnFinishLinkageSpecification(Scope *S,
                                         Decl *LinkageSpec,
                                         SourceLocation RBraceLoc);
 
 
   //===--------------------------------------------------------------------===//
   // C++ Classes
   //
   CXXRecordDecl *getCurrentClass(Scope *S, const CXXScopeSpec *SS);
   bool isCurrentClassName(const IdentifierInfo &II, Scope *S,
                           const CXXScopeSpec *SS = nullptr);
   bool isCurrentClassNameTypo(IdentifierInfo *&II, const CXXScopeSpec *SS);
 
   bool ActOnAccessSpecifier(AccessSpecifier Access, SourceLocation ASLoc,
                             SourceLocation ColonLoc,
                             const ParsedAttributesView &Attrs);
 
   NamedDecl *ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS,
                                  Declarator &D,
                                  MultiTemplateParamsArg TemplateParameterLists,
                                  Expr *BitfieldWidth, const VirtSpecifiers &VS,
                                  InClassInitStyle InitStyle);
 
   void ActOnStartCXXInClassMemberInitializer();
   void ActOnFinishCXXInClassMemberInitializer(Decl *VarDecl,
                                               SourceLocation EqualLoc,
                                               Expr *Init);
 
   MemInitResult ActOnMemInitializer(Decl *ConstructorD,
                                     Scope *S,
                                     CXXScopeSpec &SS,
                                     IdentifierInfo *MemberOrBase,
                                     ParsedType TemplateTypeTy,
                                     const DeclSpec &DS,
                                     SourceLocation IdLoc,
                                     SourceLocation LParenLoc,
                                     ArrayRef<Expr *> Args,
                                     SourceLocation RParenLoc,
                                     SourceLocation EllipsisLoc);
 
   MemInitResult ActOnMemInitializer(Decl *ConstructorD,
                                     Scope *S,
                                     CXXScopeSpec &SS,
                                     IdentifierInfo *MemberOrBase,
                                     ParsedType TemplateTypeTy,
                                     const DeclSpec &DS,
                                     SourceLocation IdLoc,
                                     Expr *InitList,
                                     SourceLocation EllipsisLoc);
 
   MemInitResult BuildMemInitializer(Decl *ConstructorD,
                                     Scope *S,
                                     CXXScopeSpec &SS,
                                     IdentifierInfo *MemberOrBase,
                                     ParsedType TemplateTypeTy,
                                     const DeclSpec &DS,
                                     SourceLocation IdLoc,
                                     Expr *Init,
                                     SourceLocation EllipsisLoc);
 
   MemInitResult BuildMemberInitializer(ValueDecl *Member,
                                        Expr *Init,
                                        SourceLocation IdLoc);
 
   MemInitResult BuildBaseInitializer(QualType BaseType,
                                      TypeSourceInfo *BaseTInfo,
                                      Expr *Init,
                                      CXXRecordDecl *ClassDecl,
                                      SourceLocation EllipsisLoc);
 
   MemInitResult BuildDelegatingInitializer(TypeSourceInfo *TInfo,
                                            Expr *Init,
                                            CXXRecordDecl *ClassDecl);
 
   bool SetDelegatingInitializer(CXXConstructorDecl *Constructor,
                                 CXXCtorInitializer *Initializer);
 
   bool SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
                            ArrayRef<CXXCtorInitializer *> Initializers = None);
 
   void SetIvarInitializers(ObjCImplementationDecl *ObjCImplementation);
 
 
   /// MarkBaseAndMemberDestructorsReferenced - Given a record decl,
   /// mark all the non-trivial destructors of its members and bases as
   /// referenced.
   void MarkBaseAndMemberDestructorsReferenced(SourceLocation Loc,
                                               CXXRecordDecl *Record);
 
   /// The list of classes whose vtables have been used within
   /// this translation unit, and the source locations at which the
   /// first use occurred.
   typedef std::pair<CXXRecordDecl*, SourceLocation> VTableUse;
 
   /// The list of vtables that are required but have not yet been
   /// materialized.
   SmallVector<VTableUse, 16> VTableUses;
 
   /// The set of classes whose vtables have been used within
   /// this translation unit, and a bit that will be true if the vtable is
   /// required to be emitted (otherwise, it should be emitted only if needed
   /// by code generation).
   llvm::DenseMap<CXXRecordDecl *, bool> VTablesUsed;
 
   /// Load any externally-stored vtable uses.
   void LoadExternalVTableUses();
 
   /// Note that the vtable for the given class was used at the
   /// given location.
   void MarkVTableUsed(SourceLocation Loc, CXXRecordDecl *Class,
                       bool DefinitionRequired = false);
 
   /// Mark the exception specifications of all virtual member functions
   /// in the given class as needed.
   void MarkVirtualMemberExceptionSpecsNeeded(SourceLocation Loc,
                                              const CXXRecordDecl *RD);
 
   /// MarkVirtualMembersReferenced - Will mark all members of the given
   /// CXXRecordDecl referenced.
   void MarkVirtualMembersReferenced(SourceLocation Loc, const CXXRecordDecl *RD,
                                     bool ConstexprOnly = false);
 
   /// Define all of the vtables that have been used in this
   /// translation unit and reference any virtual members used by those
   /// vtables.
   ///
   /// \returns true if any work was done, false otherwise.
   bool DefineUsedVTables();
 
   void AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl);
 
   void ActOnMemInitializers(Decl *ConstructorDecl,
                             SourceLocation ColonLoc,
                             ArrayRef<CXXCtorInitializer*> MemInits,
                             bool AnyErrors);
 
   /// Check class-level dllimport/dllexport attribute. The caller must
   /// ensure that referenceDLLExportedClassMethods is called some point later
   /// when all outer classes of Class are complete.
   void checkClassLevelDLLAttribute(CXXRecordDecl *Class);
   void checkClassLevelCodeSegAttribute(CXXRecordDecl *Class);
 
   void referenceDLLExportedClassMethods();
 
   void propagateDLLAttrToBaseClassTemplate(
       CXXRecordDecl *Class, Attr *ClassAttr,
       ClassTemplateSpecializationDecl *BaseTemplateSpec,
       SourceLocation BaseLoc);
 
   /// Add gsl::Pointer attribute to std::container::iterator
   /// \param ND The declaration that introduces the name
   /// std::container::iterator. \param UnderlyingRecord The record named by ND.
   void inferGslPointerAttribute(NamedDecl *ND, CXXRecordDecl *UnderlyingRecord);
 
   /// Add [[gsl::Owner]] and [[gsl::Pointer]] attributes for std:: types.
   void inferGslOwnerPointerAttribute(CXXRecordDecl *Record);
 
   /// Add [[gsl::Pointer]] attributes for std:: types.
   void inferGslPointerAttribute(TypedefNameDecl *TD);
 
   void CheckCompletedCXXClass(Scope *S, CXXRecordDecl *Record);
 
   /// Check that the C++ class annoated with "trivial_abi" satisfies all the
   /// conditions that are needed for the attribute to have an effect.
   void checkIllFormedTrivialABIStruct(CXXRecordDecl &RD);
 
   void ActOnFinishCXXMemberSpecification(Scope *S, SourceLocation RLoc,
                                          Decl *TagDecl, SourceLocation LBrac,
                                          SourceLocation RBrac,
                                          const ParsedAttributesView &AttrList);
   void ActOnFinishCXXMemberDecls();
   void ActOnFinishCXXNonNestedClass();
 
   void ActOnReenterCXXMethodParameter(Scope *S, ParmVarDecl *Param);
   unsigned ActOnReenterTemplateScope(Scope *S, Decl *Template);
   void ActOnStartDelayedMemberDeclarations(Scope *S, Decl *Record);
   void ActOnStartDelayedCXXMethodDeclaration(Scope *S, Decl *Method);
   void ActOnDelayedCXXMethodParameter(Scope *S, Decl *Param);
   void ActOnFinishDelayedMemberDeclarations(Scope *S, Decl *Record);
   void ActOnFinishDelayedCXXMethodDeclaration(Scope *S, Decl *Method);
   void ActOnFinishDelayedMemberInitializers(Decl *Record);
   void MarkAsLateParsedTemplate(FunctionDecl *FD, Decl *FnD,
                                 CachedTokens &Toks);
   void UnmarkAsLateParsedTemplate(FunctionDecl *FD);
   bool IsInsideALocalClassWithinATemplateFunction();
 
   Decl *ActOnStaticAssertDeclaration(SourceLocation StaticAssertLoc,
                                      Expr *AssertExpr,
                                      Expr *AssertMessageExpr,
                                      SourceLocation RParenLoc);
   Decl *BuildStaticAssertDeclaration(SourceLocation StaticAssertLoc,
                                      Expr *AssertExpr,
                                      StringLiteral *AssertMessageExpr,
                                      SourceLocation RParenLoc,
                                      bool Failed);
 
   FriendDecl *CheckFriendTypeDecl(SourceLocation LocStart,
                                   SourceLocation FriendLoc,
                                   TypeSourceInfo *TSInfo);
   Decl *ActOnFriendTypeDecl(Scope *S, const DeclSpec &DS,
                             MultiTemplateParamsArg TemplateParams);
   NamedDecl *ActOnFriendFunctionDecl(Scope *S, Declarator &D,
                                      MultiTemplateParamsArg TemplateParams);
 
   QualType CheckConstructorDeclarator(Declarator &D, QualType R,
                                       StorageClass& SC);
   void CheckConstructor(CXXConstructorDecl *Constructor);
   QualType CheckDestructorDeclarator(Declarator &D, QualType R,
                                      StorageClass& SC);
   bool CheckDestructor(CXXDestructorDecl *Destructor);
   void CheckConversionDeclarator(Declarator &D, QualType &R,
                                  StorageClass& SC);
   Decl *ActOnConversionDeclarator(CXXConversionDecl *Conversion);
   void CheckDeductionGuideDeclarator(Declarator &D, QualType &R,
                                      StorageClass &SC);
   void CheckDeductionGuideTemplate(FunctionTemplateDecl *TD);
 
   void CheckExplicitlyDefaultedFunction(Scope *S, FunctionDecl *MD);
 
   bool CheckExplicitlyDefaultedSpecialMember(CXXMethodDecl *MD,
                                              CXXSpecialMember CSM);
   void CheckDelayedMemberExceptionSpecs();
 
   bool CheckExplicitlyDefaultedComparison(Scope *S, FunctionDecl *MD,
                                           DefaultedComparisonKind DCK);
   void DeclareImplicitEqualityComparison(CXXRecordDecl *RD,
                                          FunctionDecl *Spaceship);
   void DefineDefaultedComparison(SourceLocation Loc, FunctionDecl *FD,
                                  DefaultedComparisonKind DCK);
 
   //===--------------------------------------------------------------------===//
   // C++ Derived Classes
   //
 
   /// ActOnBaseSpecifier - Parsed a base specifier
   CXXBaseSpecifier *CheckBaseSpecifier(CXXRecordDecl *Class,
                                        SourceRange SpecifierRange,
                                        bool Virtual, AccessSpecifier Access,
                                        TypeSourceInfo *TInfo,
                                        SourceLocation EllipsisLoc);
 
   BaseResult ActOnBaseSpecifier(Decl *classdecl,
                                 SourceRange SpecifierRange,
                                 ParsedAttributes &Attrs,
                                 bool Virtual, AccessSpecifier Access,
                                 ParsedType basetype,
                                 SourceLocation BaseLoc,
                                 SourceLocation EllipsisLoc);
 
   bool AttachBaseSpecifiers(CXXRecordDecl *Class,
                             MutableArrayRef<CXXBaseSpecifier *> Bases);
   void ActOnBaseSpecifiers(Decl *ClassDecl,
                            MutableArrayRef<CXXBaseSpecifier *> Bases);
 
   bool IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base);
   bool IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base,
                      CXXBasePaths &Paths);
 
   // FIXME: I don't like this name.
   void BuildBasePathArray(const CXXBasePaths &Paths, CXXCastPath &BasePath);
 
   bool CheckDerivedToBaseConversion(QualType Derived, QualType Base,
                                     SourceLocation Loc, SourceRange Range,
                                     CXXCastPath *BasePath = nullptr,
                                     bool IgnoreAccess = false);
   bool CheckDerivedToBaseConversion(QualType Derived, QualType Base,
                                     unsigned InaccessibleBaseID,
                                     unsigned AmbigiousBaseConvID,
                                     SourceLocation Loc, SourceRange Range,
                                     DeclarationName Name,
                                     CXXCastPath *BasePath,
                                     bool IgnoreAccess = false);
 
   std::string getAmbiguousPathsDisplayString(CXXBasePaths &Paths);
 
   bool CheckOverridingFunctionAttributes(const CXXMethodDecl *New,
                                          const CXXMethodDecl *Old);
 
   /// CheckOverridingFunctionReturnType - Checks whether the return types are
   /// covariant, according to C++ [class.virtual]p5.
   bool CheckOverridingFunctionReturnType(const CXXMethodDecl *New,
                                          const CXXMethodDecl *Old);
 
   /// CheckOverridingFunctionExceptionSpec - Checks whether the exception
   /// spec is a subset of base spec.
   bool CheckOverridingFunctionExceptionSpec(const CXXMethodDecl *New,
                                             const CXXMethodDecl *Old);
 
   bool CheckPureMethod(CXXMethodDecl *Method, SourceRange InitRange);
 
   /// CheckOverrideControl - Check C++11 override control semantics.
   void CheckOverrideControl(NamedDecl *D);
 
   /// DiagnoseAbsenceOfOverrideControl - Diagnose if 'override' keyword was
   /// not used in the declaration of an overriding method.
   void DiagnoseAbsenceOfOverrideControl(NamedDecl *D);
 
   /// CheckForFunctionMarkedFinal - Checks whether a virtual member function
   /// overrides a virtual member function marked 'final', according to
   /// C++11 [class.virtual]p4.
   bool CheckIfOverriddenFunctionIsMarkedFinal(const CXXMethodDecl *New,
                                               const CXXMethodDecl *Old);
 
 
   //===--------------------------------------------------------------------===//
   // C++ Access Control
   //
 
   enum AccessResult {
     AR_accessible,
     AR_inaccessible,
     AR_dependent,
     AR_delayed
   };
 
   bool SetMemberAccessSpecifier(NamedDecl *MemberDecl,
                                 NamedDecl *PrevMemberDecl,
                                 AccessSpecifier LexicalAS);
 
   AccessResult CheckUnresolvedMemberAccess(UnresolvedMemberExpr *E,
                                            DeclAccessPair FoundDecl);
   AccessResult CheckUnresolvedLookupAccess(UnresolvedLookupExpr *E,
                                            DeclAccessPair FoundDecl);
   AccessResult CheckAllocationAccess(SourceLocation OperatorLoc,
                                      SourceRange PlacementRange,
                                      CXXRecordDecl *NamingClass,
                                      DeclAccessPair FoundDecl,
                                      bool Diagnose = true);
   AccessResult CheckConstructorAccess(SourceLocation Loc,
                                       CXXConstructorDecl *D,
                                       DeclAccessPair FoundDecl,
                                       const InitializedEntity &Entity,
                                       bool IsCopyBindingRefToTemp = false);
   AccessResult CheckConstructorAccess(SourceLocation Loc,
                                       CXXConstructorDecl *D,
                                       DeclAccessPair FoundDecl,
                                       const InitializedEntity &Entity,
                                       const PartialDiagnostic &PDiag);
   AccessResult CheckDestructorAccess(SourceLocation Loc,
                                      CXXDestructorDecl *Dtor,
                                      const PartialDiagnostic &PDiag,
                                      QualType objectType = QualType());
   AccessResult CheckFriendAccess(NamedDecl *D);
   AccessResult CheckMemberAccess(SourceLocation UseLoc,
                                  CXXRecordDecl *NamingClass,
                                  DeclAccessPair Found);
   AccessResult
   CheckStructuredBindingMemberAccess(SourceLocation UseLoc,
                                      CXXRecordDecl *DecomposedClass,
                                      DeclAccessPair Field);
   AccessResult CheckMemberOperatorAccess(SourceLocation Loc,
                                          Expr *ObjectExpr,
                                          Expr *ArgExpr,
                                          DeclAccessPair FoundDecl);
   AccessResult CheckAddressOfMemberAccess(Expr *OvlExpr,
                                           DeclAccessPair FoundDecl);
   AccessResult CheckBaseClassAccess(SourceLocation AccessLoc,
                                     QualType Base, QualType Derived,
                                     const CXXBasePath &Path,
                                     unsigned DiagID,
                                     bool ForceCheck = false,
                                     bool ForceUnprivileged = false);
   void CheckLookupAccess(const LookupResult &R);
   bool IsSimplyAccessible(NamedDecl *Decl, CXXRecordDecl *NamingClass,
                           QualType BaseType);
   bool isMemberAccessibleForDeletion(CXXRecordDecl *NamingClass,
                                      DeclAccessPair Found, QualType ObjectType,
                                      SourceLocation Loc,
                                      const PartialDiagnostic &Diag);
   bool isMemberAccessibleForDeletion(CXXRecordDecl *NamingClass,
                                      DeclAccessPair Found,
                                      QualType ObjectType) {
     return isMemberAccessibleForDeletion(NamingClass, Found, ObjectType,
                                          SourceLocation(), PDiag());
   }
 
   void HandleDependentAccessCheck(const DependentDiagnostic &DD,
                          const MultiLevelTemplateArgumentList &TemplateArgs);
   void PerformDependentDiagnostics(const DeclContext *Pattern,
                         const MultiLevelTemplateArgumentList &TemplateArgs);
 
   void HandleDelayedAccessCheck(sema::DelayedDiagnostic &DD, Decl *Ctx);
 
   /// When true, access checking violations are treated as SFINAE
   /// failures rather than hard errors.
   bool AccessCheckingSFINAE;
 
   enum AbstractDiagSelID {
     AbstractNone = -1,
     AbstractReturnType,
     AbstractParamType,
     AbstractVariableType,
     AbstractFieldType,
     AbstractIvarType,
     AbstractSynthesizedIvarType,
     AbstractArrayType
   };
 
   bool isAbstractType(SourceLocation Loc, QualType T);
   bool RequireNonAbstractType(SourceLocation Loc, QualType T,
                               TypeDiagnoser &Diagnoser);
   template <typename... Ts>
   bool RequireNonAbstractType(SourceLocation Loc, QualType T, unsigned DiagID,
                               const Ts &...Args) {
     BoundTypeDiagnoser<Ts...> Diagnoser(DiagID, Args...);
     return RequireNonAbstractType(Loc, T, Diagnoser);
   }
 
   void DiagnoseAbstractType(const CXXRecordDecl *RD);
 
   //===--------------------------------------------------------------------===//
   // C++ Overloaded Operators [C++ 13.5]
   //
 
   bool CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl);
 
   bool CheckLiteralOperatorDeclaration(FunctionDecl *FnDecl);
 
   //===--------------------------------------------------------------------===//
   // C++ Templates [C++ 14]
   //
   void FilterAcceptableTemplateNames(LookupResult &R,
                                      bool AllowFunctionTemplates = true,
                                      bool AllowDependent = true);
   bool hasAnyAcceptableTemplateNames(LookupResult &R,
                                      bool AllowFunctionTemplates = true,
                                      bool AllowDependent = true,
                                      bool AllowNonTemplateFunctions = false);
   /// Try to interpret the lookup result D as a template-name.
   ///
   /// \param D A declaration found by name lookup.
   /// \param AllowFunctionTemplates Whether function templates should be
   ///        considered valid results.
   /// \param AllowDependent Whether unresolved using declarations (that might
   ///        name templates) should be considered valid results.
   NamedDecl *getAsTemplateNameDecl(NamedDecl *D,
                                    bool AllowFunctionTemplates = true,
                                    bool AllowDependent = true);
 
   enum class AssumedTemplateKind {
     /// This is not assumed to be a template name.
     None,
     /// This is assumed to be a template name because lookup found nothing.
     FoundNothing,
     /// This is assumed to be a template name because lookup found one or more
     /// functions (but no function templates).
     FoundFunctions,
   };
   bool LookupTemplateName(LookupResult &R, Scope *S, CXXScopeSpec &SS,
                           QualType ObjectType, bool EnteringContext,
                           bool &MemberOfUnknownSpecialization,
                           SourceLocation TemplateKWLoc = SourceLocation(),
                           AssumedTemplateKind *ATK = nullptr,
                           bool Disambiguation = false);
 
   TemplateNameKind isTemplateName(Scope *S,
                                   CXXScopeSpec &SS,
                                   bool hasTemplateKeyword,
                                   const UnqualifiedId &Name,
                                   ParsedType ObjectType,
                                   bool EnteringContext,
                                   TemplateTy &Template,
                                   bool &MemberOfUnknownSpecialization,
                                   bool Disambiguation = false);
 
   /// Try to resolve an undeclared template name as a type template.
   ///
   /// Sets II to the identifier corresponding to the template name, and updates
   /// Name to a corresponding (typo-corrected) type template name and TNK to
   /// the corresponding kind, if possible.
   void ActOnUndeclaredTypeTemplateName(Scope *S, TemplateTy &Name,
                                        TemplateNameKind &TNK,
                                        SourceLocation NameLoc,
                                        IdentifierInfo *&II);
 
   bool resolveAssumedTemplateNameAsType(Scope *S, TemplateName &Name,
                                         SourceLocation NameLoc,
                                         bool Diagnose = true);
 
   /// Determine whether a particular identifier might be the name in a C++1z
   /// deduction-guide declaration.
   bool isDeductionGuideName(Scope *S, const IdentifierInfo &Name,
                             SourceLocation NameLoc,
                             ParsedTemplateTy *Template = nullptr);
 
   bool DiagnoseUnknownTemplateName(const IdentifierInfo &II,
                                    SourceLocation IILoc,
                                    Scope *S,
                                    const CXXScopeSpec *SS,
                                    TemplateTy &SuggestedTemplate,
                                    TemplateNameKind &SuggestedKind);
 
   bool DiagnoseUninstantiableTemplate(SourceLocation PointOfInstantiation,
                                       NamedDecl *Instantiation,
                                       bool InstantiatedFromMember,
                                       const NamedDecl *Pattern,
                                       const NamedDecl *PatternDef,
                                       TemplateSpecializationKind TSK,
                                       bool Complain = true);
 
   void DiagnoseTemplateParameterShadow(SourceLocation Loc, Decl *PrevDecl);
   TemplateDecl *AdjustDeclIfTemplate(Decl *&Decl);
 
   NamedDecl *ActOnTypeParameter(Scope *S, bool Typename,
                                 SourceLocation EllipsisLoc,
                                 SourceLocation KeyLoc,
                                 IdentifierInfo *ParamName,
                                 SourceLocation ParamNameLoc,
                                 unsigned Depth, unsigned Position,
                                 SourceLocation EqualLoc,
                                 ParsedType DefaultArg, bool HasTypeConstraint);
 
   bool ActOnTypeConstraint(const CXXScopeSpec &SS,
                            TemplateIdAnnotation *TypeConstraint,
                            TemplateTypeParmDecl *ConstrainedParameter,
                            SourceLocation EllipsisLoc);
 
   bool AttachTypeConstraint(NestedNameSpecifierLoc NS,
                             DeclarationNameInfo NameInfo,
                             ConceptDecl *NamedConcept,
                             const TemplateArgumentListInfo *TemplateArgs,
                             TemplateTypeParmDecl *ConstrainedParameter,
                             SourceLocation EllipsisLoc);
 
   bool AttachTypeConstraint(AutoTypeLoc TL,
                             NonTypeTemplateParmDecl *ConstrainedParameter,
                             SourceLocation EllipsisLoc);
 
   QualType CheckNonTypeTemplateParameterType(TypeSourceInfo *&TSI,
                                              SourceLocation Loc);
   QualType CheckNonTypeTemplateParameterType(QualType T, SourceLocation Loc);
 
   NamedDecl *ActOnNonTypeTemplateParameter(Scope *S, Declarator &D,
                                       unsigned Depth,
                                       unsigned Position,
                                       SourceLocation EqualLoc,
                                       Expr *DefaultArg);
   NamedDecl *ActOnTemplateTemplateParameter(Scope *S,
                                        SourceLocation TmpLoc,
                                        TemplateParameterList *Params,
                                        SourceLocation EllipsisLoc,
                                        IdentifierInfo *ParamName,
                                        SourceLocation ParamNameLoc,
                                        unsigned Depth,
                                        unsigned Position,
                                        SourceLocation EqualLoc,
                                        ParsedTemplateArgument DefaultArg);
 
   TemplateParameterList *
   ActOnTemplateParameterList(unsigned Depth,
                              SourceLocation ExportLoc,
                              SourceLocation TemplateLoc,
                              SourceLocation LAngleLoc,
                              ArrayRef<NamedDecl *> Params,
                              SourceLocation RAngleLoc,
                              Expr *RequiresClause);
 
   /// The context in which we are checking a template parameter list.
   enum TemplateParamListContext {
     TPC_ClassTemplate,
     TPC_VarTemplate,
     TPC_FunctionTemplate,
     TPC_ClassTemplateMember,
     TPC_FriendClassTemplate,
     TPC_FriendFunctionTemplate,
     TPC_FriendFunctionTemplateDefinition,
     TPC_TypeAliasTemplate
   };
 
   bool CheckTemplateParameterList(TemplateParameterList *NewParams,
                                   TemplateParameterList *OldParams,
                                   TemplateParamListContext TPC,
                                   SkipBodyInfo *SkipBody = nullptr);
   TemplateParameterList *MatchTemplateParametersToScopeSpecifier(
       SourceLocation DeclStartLoc, SourceLocation DeclLoc,
       const CXXScopeSpec &SS, TemplateIdAnnotation *TemplateId,
       ArrayRef<TemplateParameterList *> ParamLists,
       bool IsFriend, bool &IsMemberSpecialization, bool &Invalid,
       bool SuppressDiagnostic = false);
 
   DeclResult CheckClassTemplate(
       Scope *S, unsigned TagSpec, TagUseKind TUK, SourceLocation KWLoc,
       CXXScopeSpec &SS, IdentifierInfo *Name, SourceLocation NameLoc,
       const ParsedAttributesView &Attr, TemplateParameterList *TemplateParams,
       AccessSpecifier AS, SourceLocation ModulePrivateLoc,
       SourceLocation FriendLoc, unsigned NumOuterTemplateParamLists,
       TemplateParameterList **OuterTemplateParamLists,
       SkipBodyInfo *SkipBody = nullptr);
 
   TemplateArgumentLoc getTrivialTemplateArgumentLoc(const TemplateArgument &Arg,
                                                     QualType NTTPType,
                                                     SourceLocation Loc);
 
   /// Get a template argument mapping the given template parameter to itself,
   /// e.g. for X in \c template<int X>, this would return an expression template
   /// argument referencing X.
   TemplateArgumentLoc getIdentityTemplateArgumentLoc(NamedDecl *Param,
                                                      SourceLocation Location);
 
   void translateTemplateArguments(const ASTTemplateArgsPtr &In,
                                   TemplateArgumentListInfo &Out);
 
   ParsedTemplateArgument ActOnTemplateTypeArgument(TypeResult ParsedType);
 
   void NoteAllFoundTemplates(TemplateName Name);
 
   QualType CheckTemplateIdType(TemplateName Template,
                                SourceLocation TemplateLoc,
                               TemplateArgumentListInfo &TemplateArgs);
 
   TypeResult
   ActOnTemplateIdType(Scope *S, CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
                       TemplateTy Template, IdentifierInfo *TemplateII,
                       SourceLocation TemplateIILoc, SourceLocation LAngleLoc,
                       ASTTemplateArgsPtr TemplateArgs, SourceLocation RAngleLoc,
                       bool IsCtorOrDtorName = false, bool IsClassName = false);
 
   /// Parsed an elaborated-type-specifier that refers to a template-id,
   /// such as \c class T::template apply<U>.
   TypeResult ActOnTagTemplateIdType(TagUseKind TUK,
                                     TypeSpecifierType TagSpec,
                                     SourceLocation TagLoc,
                                     CXXScopeSpec &SS,
                                     SourceLocation TemplateKWLoc,
                                     TemplateTy TemplateD,
                                     SourceLocation TemplateLoc,
                                     SourceLocation LAngleLoc,
                                     ASTTemplateArgsPtr TemplateArgsIn,
                                     SourceLocation RAngleLoc);
 
   DeclResult ActOnVarTemplateSpecialization(
       Scope *S, Declarator &D, TypeSourceInfo *DI,
       SourceLocation TemplateKWLoc, TemplateParameterList *TemplateParams,
       StorageClass SC, bool IsPartialSpecialization);
 
   DeclResult CheckVarTemplateId(VarTemplateDecl *Template,
                                 SourceLocation TemplateLoc,
                                 SourceLocation TemplateNameLoc,
                                 const TemplateArgumentListInfo &TemplateArgs);
 
   ExprResult CheckVarTemplateId(const CXXScopeSpec &SS,
                                 const DeclarationNameInfo &NameInfo,
                                 VarTemplateDecl *Template,
                                 SourceLocation TemplateLoc,
                                 const TemplateArgumentListInfo *TemplateArgs);
 
   ExprResult
   CheckConceptTemplateId(const CXXScopeSpec &SS,
                          SourceLocation TemplateKWLoc,
                          const DeclarationNameInfo &ConceptNameInfo,
                          NamedDecl *FoundDecl, ConceptDecl *NamedConcept,
                          const TemplateArgumentListInfo *TemplateArgs);
 
   void diagnoseMissingTemplateArguments(TemplateName Name, SourceLocation Loc);
 
   ExprResult BuildTemplateIdExpr(const CXXScopeSpec &SS,
                                  SourceLocation TemplateKWLoc,
                                  LookupResult &R,
                                  bool RequiresADL,
                                const TemplateArgumentListInfo *TemplateArgs);
 
   ExprResult BuildQualifiedTemplateIdExpr(CXXScopeSpec &SS,
                                           SourceLocation TemplateKWLoc,
                                const DeclarationNameInfo &NameInfo,
                                const TemplateArgumentListInfo *TemplateArgs);
 
   TemplateNameKind ActOnDependentTemplateName(
       Scope *S, CXXScopeSpec &SS, SourceLocation TemplateKWLoc,
       const UnqualifiedId &Name, ParsedType ObjectType, bool EnteringContext,
       TemplateTy &Template, bool AllowInjectedClassName = false);
 
   DeclResult ActOnClassTemplateSpecialization(
       Scope *S, unsigned TagSpec, TagUseKind TUK, SourceLocation KWLoc,
       SourceLocation ModulePrivateLoc, CXXScopeSpec &SS,
       TemplateIdAnnotation &TemplateId, const ParsedAttributesView &Attr,
       MultiTemplateParamsArg TemplateParameterLists,
       SkipBodyInfo *SkipBody = nullptr);
 
   bool CheckTemplatePartialSpecializationArgs(SourceLocation Loc,
                                               TemplateDecl *PrimaryTemplate,
                                               unsigned NumExplicitArgs,
                                               ArrayRef<TemplateArgument> Args);
   void CheckTemplatePartialSpecialization(
       ClassTemplatePartialSpecializationDecl *Partial);
   void CheckTemplatePartialSpecialization(
       VarTemplatePartialSpecializationDecl *Partial);
 
   Decl *ActOnTemplateDeclarator(Scope *S,
                                 MultiTemplateParamsArg TemplateParameterLists,
                                 Declarator &D);
 
   bool
   CheckSpecializationInstantiationRedecl(SourceLocation NewLoc,
                                          TemplateSpecializationKind NewTSK,
                                          NamedDecl *PrevDecl,
                                          TemplateSpecializationKind PrevTSK,
                                          SourceLocation PrevPtOfInstantiation,
                                          bool &SuppressNew);
 
   bool CheckDependentFunctionTemplateSpecialization(FunctionDecl *FD,
                     const TemplateArgumentListInfo &ExplicitTemplateArgs,
                                                     LookupResult &Previous);
 
   bool CheckFunctionTemplateSpecialization(
       FunctionDecl *FD, TemplateArgumentListInfo *ExplicitTemplateArgs,
       LookupResult &Previous, bool QualifiedFriend = false);
   bool CheckMemberSpecialization(NamedDecl *Member, LookupResult &Previous);
   void CompleteMemberSpecialization(NamedDecl *Member, LookupResult &Previous);
 
   DeclResult ActOnExplicitInstantiation(
       Scope *S, SourceLocation ExternLoc, SourceLocation TemplateLoc,
       unsigned TagSpec, SourceLocation KWLoc, const CXXScopeSpec &SS,
       TemplateTy Template, SourceLocation TemplateNameLoc,
       SourceLocation LAngleLoc, ASTTemplateArgsPtr TemplateArgs,
       SourceLocation RAngleLoc, const ParsedAttributesView &Attr);
 
   DeclResult ActOnExplicitInstantiation(Scope *S, SourceLocation ExternLoc,
                                         SourceLocation TemplateLoc,
                                         unsigned TagSpec, SourceLocation KWLoc,
                                         CXXScopeSpec &SS, IdentifierInfo *Name,
                                         SourceLocation NameLoc,
                                         const ParsedAttributesView &Attr);
 
   DeclResult ActOnExplicitInstantiation(Scope *S,
                                         SourceLocation ExternLoc,
                                         SourceLocation TemplateLoc,
                                         Declarator &D);
 
   TemplateArgumentLoc
   SubstDefaultTemplateArgumentIfAvailable(TemplateDecl *Template,
                                           SourceLocation TemplateLoc,
                                           SourceLocation RAngleLoc,
                                           Decl *Param,
                                           SmallVectorImpl<TemplateArgument>
                                             &Converted,
                                           bool &HasDefaultArg);
 
   /// Specifies the context in which a particular template
   /// argument is being checked.
   enum CheckTemplateArgumentKind {
     /// The template argument was specified in the code or was
     /// instantiated with some deduced template arguments.
     CTAK_Specified,
 
     /// The template argument was deduced via template argument
     /// deduction.
     CTAK_Deduced,
 
     /// The template argument was deduced from an array bound
     /// via template argument deduction.
     CTAK_DeducedFromArrayBound
   };
 
   bool CheckTemplateArgument(NamedDecl *Param,
                              TemplateArgumentLoc &Arg,
                              NamedDecl *Template,
                              SourceLocation TemplateLoc,
                              SourceLocation RAngleLoc,
                              unsigned ArgumentPackIndex,
                            SmallVectorImpl<TemplateArgument> &Converted,
                              CheckTemplateArgumentKind CTAK = CTAK_Specified);
 
   /// Check that the given template arguments can be be provided to
   /// the given template, converting the arguments along the way.
   ///
   /// \param Template The template to which the template arguments are being
   /// provided.
   ///
   /// \param TemplateLoc The location of the template name in the source.
   ///
   /// \param TemplateArgs The list of template arguments. If the template is
   /// a template template parameter, this function may extend the set of
   /// template arguments to also include substituted, defaulted template
   /// arguments.
   ///
   /// \param PartialTemplateArgs True if the list of template arguments is
   /// intentionally partial, e.g., because we're checking just the initial
   /// set of template arguments.
   ///
   /// \param Converted Will receive the converted, canonicalized template
   /// arguments.
   ///
   /// \param UpdateArgsWithConversions If \c true, update \p TemplateArgs to
   /// contain the converted forms of the template arguments as written.
   /// Otherwise, \p TemplateArgs will not be modified.
   ///
   /// \param ConstraintsNotSatisfied If provided, and an error occured, will
   /// receive true if the cause for the error is the associated constraints of
   /// the template not being satisfied by the template arguments.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool CheckTemplateArgumentList(TemplateDecl *Template,
                                  SourceLocation TemplateLoc,
                                  TemplateArgumentListInfo &TemplateArgs,
                                  bool PartialTemplateArgs,
                                  SmallVectorImpl<TemplateArgument> &Converted,
                                  bool UpdateArgsWithConversions = true,
                                  bool *ConstraintsNotSatisfied = nullptr);
 
   bool CheckTemplateTypeArgument(TemplateTypeParmDecl *Param,
                                  TemplateArgumentLoc &Arg,
                            SmallVectorImpl<TemplateArgument> &Converted);
 
   bool CheckTemplateArgument(TemplateTypeParmDecl *Param,
                              TypeSourceInfo *Arg);
   ExprResult CheckTemplateArgument(NonTypeTemplateParmDecl *Param,
                                    QualType InstantiatedParamType, Expr *Arg,
                                    TemplateArgument &Converted,
                                CheckTemplateArgumentKind CTAK = CTAK_Specified);
   bool CheckTemplateTemplateArgument(TemplateTemplateParmDecl *Param,
                                      TemplateParameterList *Params,
                                      TemplateArgumentLoc &Arg);
 
   ExprResult
   BuildExpressionFromDeclTemplateArgument(const TemplateArgument &Arg,
                                           QualType ParamType,
                                           SourceLocation Loc);
   ExprResult
   BuildExpressionFromIntegralTemplateArgument(const TemplateArgument &Arg,
                                               SourceLocation Loc);
 
   /// Enumeration describing how template parameter lists are compared
   /// for equality.
   enum TemplateParameterListEqualKind {
     /// We are matching the template parameter lists of two templates
     /// that might be redeclarations.
     ///
     /// \code
     /// template<typename T> struct X;
     /// template<typename T> struct X;
     /// \endcode
     TPL_TemplateMatch,
 
     /// We are matching the template parameter lists of two template
     /// template parameters as part of matching the template parameter lists
     /// of two templates that might be redeclarations.
     ///
     /// \code
     /// template<template<int I> class TT> struct X;
     /// template<template<int Value> class Other> struct X;
     /// \endcode
     TPL_TemplateTemplateParmMatch,
 
     /// We are matching the template parameter lists of a template
     /// template argument against the template parameter lists of a template
     /// template parameter.
     ///
     /// \code
     /// template<template<int Value> class Metafun> struct X;
     /// template<int Value> struct integer_c;
     /// X<integer_c> xic;
     /// \endcode
     TPL_TemplateTemplateArgumentMatch
   };
 
   bool TemplateParameterListsAreEqual(TemplateParameterList *New,
                                       TemplateParameterList *Old,
                                       bool Complain,
                                       TemplateParameterListEqualKind Kind,
                                       SourceLocation TemplateArgLoc
                                         = SourceLocation());
 
   bool CheckTemplateDeclScope(Scope *S, TemplateParameterList *TemplateParams);
 
   /// Called when the parser has parsed a C++ typename
   /// specifier, e.g., "typename T::type".
   ///
   /// \param S The scope in which this typename type occurs.
   /// \param TypenameLoc the location of the 'typename' keyword
   /// \param SS the nested-name-specifier following the typename (e.g., 'T::').
   /// \param II the identifier we're retrieving (e.g., 'type' in the example).
   /// \param IdLoc the location of the identifier.
   TypeResult
   ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
                     const CXXScopeSpec &SS, const IdentifierInfo &II,
                     SourceLocation IdLoc);
 
   /// Called when the parser has parsed a C++ typename
   /// specifier that ends in a template-id, e.g.,
   /// "typename MetaFun::template apply<T1, T2>".
   ///
   /// \param S The scope in which this typename type occurs.
   /// \param TypenameLoc the location of the 'typename' keyword
   /// \param SS the nested-name-specifier following the typename (e.g., 'T::').
   /// \param TemplateLoc the location of the 'template' keyword, if any.
   /// \param TemplateName The template name.
   /// \param TemplateII The identifier used to name the template.
   /// \param TemplateIILoc The location of the template name.
   /// \param LAngleLoc The location of the opening angle bracket  ('<').
   /// \param TemplateArgs The template arguments.
   /// \param RAngleLoc The location of the closing angle bracket  ('>').
   TypeResult
   ActOnTypenameType(Scope *S, SourceLocation TypenameLoc,
                     const CXXScopeSpec &SS,
                     SourceLocation TemplateLoc,
                     TemplateTy TemplateName,
                     IdentifierInfo *TemplateII,
                     SourceLocation TemplateIILoc,
                     SourceLocation LAngleLoc,
                     ASTTemplateArgsPtr TemplateArgs,
                     SourceLocation RAngleLoc);
 
   QualType CheckTypenameType(ElaboratedTypeKeyword Keyword,
                              SourceLocation KeywordLoc,
                              NestedNameSpecifierLoc QualifierLoc,
                              const IdentifierInfo &II,
                              SourceLocation IILoc,
                              TypeSourceInfo **TSI,
                              bool DeducedTSTContext);
 
   QualType CheckTypenameType(ElaboratedTypeKeyword Keyword,
                              SourceLocation KeywordLoc,
                              NestedNameSpecifierLoc QualifierLoc,
                              const IdentifierInfo &II,
                              SourceLocation IILoc,
                              bool DeducedTSTContext = true);
 
 
   TypeSourceInfo *RebuildTypeInCurrentInstantiation(TypeSourceInfo *T,
                                                     SourceLocation Loc,
                                                     DeclarationName Name);
   bool RebuildNestedNameSpecifierInCurrentInstantiation(CXXScopeSpec &SS);
 
   ExprResult RebuildExprInCurrentInstantiation(Expr *E);
   bool RebuildTemplateParamsInCurrentInstantiation(
                                                 TemplateParameterList *Params);
 
   std::string
   getTemplateArgumentBindingsText(const TemplateParameterList *Params,
                                   const TemplateArgumentList &Args);
 
   std::string
   getTemplateArgumentBindingsText(const TemplateParameterList *Params,
                                   const TemplateArgument *Args,
                                   unsigned NumArgs);
 
   //===--------------------------------------------------------------------===//
   // C++ Concepts
   //===--------------------------------------------------------------------===//
   Decl *ActOnConceptDefinition(
       Scope *S, MultiTemplateParamsArg TemplateParameterLists,
       IdentifierInfo *Name, SourceLocation NameLoc, Expr *ConstraintExpr);
 
   RequiresExprBodyDecl *
   ActOnStartRequiresExpr(SourceLocation RequiresKWLoc,
                          ArrayRef<ParmVarDecl *> LocalParameters,
                          Scope *BodyScope);
   void ActOnFinishRequiresExpr();
   concepts::Requirement *ActOnSimpleRequirement(Expr *E);
   concepts::Requirement *ActOnTypeRequirement(
       SourceLocation TypenameKWLoc, CXXScopeSpec &SS, SourceLocation NameLoc,
       IdentifierInfo *TypeName, TemplateIdAnnotation *TemplateId);
   concepts::Requirement *ActOnCompoundRequirement(Expr *E,
                                                   SourceLocation NoexceptLoc);
   concepts::Requirement *
   ActOnCompoundRequirement(
       Expr *E, SourceLocation NoexceptLoc, CXXScopeSpec &SS,
       TemplateIdAnnotation *TypeConstraint, unsigned Depth);
   concepts::Requirement *ActOnNestedRequirement(Expr *Constraint);
   concepts::ExprRequirement *
   BuildExprRequirement(
       Expr *E, bool IsSatisfied, SourceLocation NoexceptLoc,
       concepts::ExprRequirement::ReturnTypeRequirement ReturnTypeRequirement);
   concepts::ExprRequirement *
   BuildExprRequirement(
       concepts::Requirement::SubstitutionDiagnostic *ExprSubstDiag,
       bool IsSatisfied, SourceLocation NoexceptLoc,
       concepts::ExprRequirement::ReturnTypeRequirement ReturnTypeRequirement);
   concepts::TypeRequirement *BuildTypeRequirement(TypeSourceInfo *Type);
   concepts::TypeRequirement *
   BuildTypeRequirement(
       concepts::Requirement::SubstitutionDiagnostic *SubstDiag);
   concepts::NestedRequirement *BuildNestedRequirement(Expr *E);
   concepts::NestedRequirement *
   BuildNestedRequirement(
       concepts::Requirement::SubstitutionDiagnostic *SubstDiag);
   ExprResult ActOnRequiresExpr(SourceLocation RequiresKWLoc,
                                RequiresExprBodyDecl *Body,
                                ArrayRef<ParmVarDecl *> LocalParameters,
                                ArrayRef<concepts::Requirement *> Requirements,
                                SourceLocation ClosingBraceLoc);
 
   //===--------------------------------------------------------------------===//
   // C++ Variadic Templates (C++0x [temp.variadic])
   //===--------------------------------------------------------------------===//
 
   /// Determine whether an unexpanded parameter pack might be permitted in this
   /// location. Useful for error recovery.
   bool isUnexpandedParameterPackPermitted();
 
   /// The context in which an unexpanded parameter pack is
   /// being diagnosed.
   ///
   /// Note that the values of this enumeration line up with the first
   /// argument to the \c err_unexpanded_parameter_pack diagnostic.
   enum UnexpandedParameterPackContext {
     /// An arbitrary expression.
     UPPC_Expression = 0,
 
     /// The base type of a class type.
     UPPC_BaseType,
 
     /// The type of an arbitrary declaration.
     UPPC_DeclarationType,
 
     /// The type of a data member.
     UPPC_DataMemberType,
 
     /// The size of a bit-field.
     UPPC_BitFieldWidth,
 
     /// The expression in a static assertion.
     UPPC_StaticAssertExpression,
 
     /// The fixed underlying type of an enumeration.
     UPPC_FixedUnderlyingType,
 
     /// The enumerator value.
     UPPC_EnumeratorValue,
 
     /// A using declaration.
     UPPC_UsingDeclaration,
 
     /// A friend declaration.
     UPPC_FriendDeclaration,
 
     /// A declaration qualifier.
     UPPC_DeclarationQualifier,
 
     /// An initializer.
     UPPC_Initializer,
 
     /// A default argument.
     UPPC_DefaultArgument,
 
     /// The type of a non-type template parameter.
     UPPC_NonTypeTemplateParameterType,
 
     /// The type of an exception.
     UPPC_ExceptionType,
 
     /// Partial specialization.
     UPPC_PartialSpecialization,
 
     /// Microsoft __if_exists.
     UPPC_IfExists,
 
     /// Microsoft __if_not_exists.
     UPPC_IfNotExists,
 
     /// Lambda expression.
     UPPC_Lambda,
 
     /// Block expression,
     UPPC_Block,
 
     /// A type constraint,
     UPPC_TypeConstraint
   };
 
   /// Diagnose unexpanded parameter packs.
   ///
   /// \param Loc The location at which we should emit the diagnostic.
   ///
   /// \param UPPC The context in which we are diagnosing unexpanded
   /// parameter packs.
   ///
   /// \param Unexpanded the set of unexpanded parameter packs.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool DiagnoseUnexpandedParameterPacks(SourceLocation Loc,
                                         UnexpandedParameterPackContext UPPC,
                                   ArrayRef<UnexpandedParameterPack> Unexpanded);
 
   /// If the given type contains an unexpanded parameter pack,
   /// diagnose the error.
   ///
   /// \param Loc The source location where a diagnostc should be emitted.
   ///
   /// \param T The type that is being checked for unexpanded parameter
   /// packs.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool DiagnoseUnexpandedParameterPack(SourceLocation Loc, TypeSourceInfo *T,
                                        UnexpandedParameterPackContext UPPC);
 
   /// If the given expression contains an unexpanded parameter
   /// pack, diagnose the error.
   ///
   /// \param E The expression that is being checked for unexpanded
   /// parameter packs.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool DiagnoseUnexpandedParameterPack(Expr *E,
                        UnexpandedParameterPackContext UPPC = UPPC_Expression);
 
   /// If the given nested-name-specifier contains an unexpanded
   /// parameter pack, diagnose the error.
   ///
   /// \param SS The nested-name-specifier that is being checked for
   /// unexpanded parameter packs.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool DiagnoseUnexpandedParameterPack(const CXXScopeSpec &SS,
                                        UnexpandedParameterPackContext UPPC);
 
   /// If the given name contains an unexpanded parameter pack,
   /// diagnose the error.
   ///
   /// \param NameInfo The name (with source location information) that
   /// is being checked for unexpanded parameter packs.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool DiagnoseUnexpandedParameterPack(const DeclarationNameInfo &NameInfo,
                                        UnexpandedParameterPackContext UPPC);
 
   /// If the given template name contains an unexpanded parameter pack,
   /// diagnose the error.
   ///
   /// \param Loc The location of the template name.
   ///
   /// \param Template The template name that is being checked for unexpanded
   /// parameter packs.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool DiagnoseUnexpandedParameterPack(SourceLocation Loc,
                                        TemplateName Template,
                                        UnexpandedParameterPackContext UPPC);
 
   /// If the given template argument contains an unexpanded parameter
   /// pack, diagnose the error.
   ///
   /// \param Arg The template argument that is being checked for unexpanded
   /// parameter packs.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool DiagnoseUnexpandedParameterPack(TemplateArgumentLoc Arg,
                                        UnexpandedParameterPackContext UPPC);
 
   /// Collect the set of unexpanded parameter packs within the given
   /// template argument.
   ///
   /// \param Arg The template argument that will be traversed to find
   /// unexpanded parameter packs.
   void collectUnexpandedParameterPacks(TemplateArgument Arg,
                    SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
 
   /// Collect the set of unexpanded parameter packs within the given
   /// template argument.
   ///
   /// \param Arg The template argument that will be traversed to find
   /// unexpanded parameter packs.
   void collectUnexpandedParameterPacks(TemplateArgumentLoc Arg,
                     SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
 
   /// Collect the set of unexpanded parameter packs within the given
   /// type.
   ///
   /// \param T The type that will be traversed to find
   /// unexpanded parameter packs.
   void collectUnexpandedParameterPacks(QualType T,
                    SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
 
   /// Collect the set of unexpanded parameter packs within the given
   /// type.
   ///
   /// \param TL The type that will be traversed to find
   /// unexpanded parameter packs.
   void collectUnexpandedParameterPacks(TypeLoc TL,
                    SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
 
   /// Collect the set of unexpanded parameter packs within the given
   /// nested-name-specifier.
   ///
   /// \param NNS The nested-name-specifier that will be traversed to find
   /// unexpanded parameter packs.
   void collectUnexpandedParameterPacks(NestedNameSpecifierLoc NNS,
                          SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
 
   /// Collect the set of unexpanded parameter packs within the given
   /// name.
   ///
   /// \param NameInfo The name that will be traversed to find
   /// unexpanded parameter packs.
   void collectUnexpandedParameterPacks(const DeclarationNameInfo &NameInfo,
                          SmallVectorImpl<UnexpandedParameterPack> &Unexpanded);
 
   /// Invoked when parsing a template argument followed by an
   /// ellipsis, which creates a pack expansion.
   ///
   /// \param Arg The template argument preceding the ellipsis, which
   /// may already be invalid.
   ///
   /// \param EllipsisLoc The location of the ellipsis.
   ParsedTemplateArgument ActOnPackExpansion(const ParsedTemplateArgument &Arg,
                                             SourceLocation EllipsisLoc);
 
   /// Invoked when parsing a type followed by an ellipsis, which
   /// creates a pack expansion.
   ///
   /// \param Type The type preceding the ellipsis, which will become
   /// the pattern of the pack expansion.
   ///
   /// \param EllipsisLoc The location of the ellipsis.
   TypeResult ActOnPackExpansion(ParsedType Type, SourceLocation EllipsisLoc);
 
   /// Construct a pack expansion type from the pattern of the pack
   /// expansion.
   TypeSourceInfo *CheckPackExpansion(TypeSourceInfo *Pattern,
                                      SourceLocation EllipsisLoc,
                                      Optional<unsigned> NumExpansions);
 
   /// Construct a pack expansion type from the pattern of the pack
   /// expansion.
   QualType CheckPackExpansion(QualType Pattern,
                               SourceRange PatternRange,
                               SourceLocation EllipsisLoc,
                               Optional<unsigned> NumExpansions);
 
   /// Invoked when parsing an expression followed by an ellipsis, which
   /// creates a pack expansion.
   ///
   /// \param Pattern The expression preceding the ellipsis, which will become
   /// the pattern of the pack expansion.
   ///
   /// \param EllipsisLoc The location of the ellipsis.
   ExprResult ActOnPackExpansion(Expr *Pattern, SourceLocation EllipsisLoc);
 
   /// Invoked when parsing an expression followed by an ellipsis, which
   /// creates a pack expansion.
   ///
   /// \param Pattern The expression preceding the ellipsis, which will become
   /// the pattern of the pack expansion.
   ///
   /// \param EllipsisLoc The location of the ellipsis.
   ExprResult CheckPackExpansion(Expr *Pattern, SourceLocation EllipsisLoc,
                                 Optional<unsigned> NumExpansions);
 
   /// Determine whether we could expand a pack expansion with the
   /// given set of parameter packs into separate arguments by repeatedly
   /// transforming the pattern.
   ///
   /// \param EllipsisLoc The location of the ellipsis that identifies the
   /// pack expansion.
   ///
   /// \param PatternRange The source range that covers the entire pattern of
   /// the pack expansion.
   ///
   /// \param Unexpanded The set of unexpanded parameter packs within the
   /// pattern.
   ///
   /// \param ShouldExpand Will be set to \c true if the transformer should
   /// expand the corresponding pack expansions into separate arguments. When
   /// set, \c NumExpansions must also be set.
   ///
   /// \param RetainExpansion Whether the caller should add an unexpanded
   /// pack expansion after all of the expanded arguments. This is used
   /// when extending explicitly-specified template argument packs per
   /// C++0x [temp.arg.explicit]p9.
   ///
   /// \param NumExpansions The number of separate arguments that will be in
   /// the expanded form of the corresponding pack expansion. This is both an
   /// input and an output parameter, which can be set by the caller if the
   /// number of expansions is known a priori (e.g., due to a prior substitution)
   /// and will be set by the callee when the number of expansions is known.
   /// The callee must set this value when \c ShouldExpand is \c true; it may
   /// set this value in other cases.
   ///
   /// \returns true if an error occurred (e.g., because the parameter packs
   /// are to be instantiated with arguments of different lengths), false
   /// otherwise. If false, \c ShouldExpand (and possibly \c NumExpansions)
   /// must be set.
   bool CheckParameterPacksForExpansion(SourceLocation EllipsisLoc,
                                        SourceRange PatternRange,
                              ArrayRef<UnexpandedParameterPack> Unexpanded,
                              const MultiLevelTemplateArgumentList &TemplateArgs,
                                        bool &ShouldExpand,
                                        bool &RetainExpansion,
                                        Optional<unsigned> &NumExpansions);
 
   /// Determine the number of arguments in the given pack expansion
   /// type.
   ///
   /// This routine assumes that the number of arguments in the expansion is
   /// consistent across all of the unexpanded parameter packs in its pattern.
   ///
   /// Returns an empty Optional if the type can't be expanded.
   Optional<unsigned> getNumArgumentsInExpansion(QualType T,
       const MultiLevelTemplateArgumentList &TemplateArgs);
 
   /// Determine whether the given declarator contains any unexpanded
   /// parameter packs.
   ///
   /// This routine is used by the parser to disambiguate function declarators
   /// with an ellipsis prior to the ')', e.g.,
   ///
   /// \code
   ///   void f(T...);
   /// \endcode
   ///
   /// To determine whether we have an (unnamed) function parameter pack or
   /// a variadic function.
   ///
   /// \returns true if the declarator contains any unexpanded parameter packs,
   /// false otherwise.
   bool containsUnexpandedParameterPacks(Declarator &D);
 
   /// Returns the pattern of the pack expansion for a template argument.
   ///
   /// \param OrigLoc The template argument to expand.
   ///
   /// \param Ellipsis Will be set to the location of the ellipsis.
   ///
   /// \param NumExpansions Will be set to the number of expansions that will
   /// be generated from this pack expansion, if known a priori.
   TemplateArgumentLoc getTemplateArgumentPackExpansionPattern(
       TemplateArgumentLoc OrigLoc,
       SourceLocation &Ellipsis,
       Optional<unsigned> &NumExpansions) const;
 
   /// Given a template argument that contains an unexpanded parameter pack, but
   /// which has already been substituted, attempt to determine the number of
   /// elements that will be produced once this argument is fully-expanded.
   ///
   /// This is intended for use when transforming 'sizeof...(Arg)' in order to
   /// avoid actually expanding the pack where possible.
   Optional<unsigned> getFullyPackExpandedSize(TemplateArgument Arg);
 
   //===--------------------------------------------------------------------===//
   // C++ Template Argument Deduction (C++ [temp.deduct])
   //===--------------------------------------------------------------------===//
 
   /// Adjust the type \p ArgFunctionType to match the calling convention,
   /// noreturn, and optionally the exception specification of \p FunctionType.
   /// Deduction often wants to ignore these properties when matching function
   /// types.
   QualType adjustCCAndNoReturn(QualType ArgFunctionType, QualType FunctionType,
                                bool AdjustExceptionSpec = false);
 
   /// Describes the result of template argument deduction.
   ///
   /// The TemplateDeductionResult enumeration describes the result of
   /// template argument deduction, as returned from
   /// DeduceTemplateArguments(). The separate TemplateDeductionInfo
   /// structure provides additional information about the results of
   /// template argument deduction, e.g., the deduced template argument
   /// list (if successful) or the specific template parameters or
   /// deduced arguments that were involved in the failure.
   enum TemplateDeductionResult {
     /// Template argument deduction was successful.
     TDK_Success = 0,
     /// The declaration was invalid; do nothing.
     TDK_Invalid,
     /// Template argument deduction exceeded the maximum template
     /// instantiation depth (which has already been diagnosed).
     TDK_InstantiationDepth,
     /// Template argument deduction did not deduce a value
     /// for every template parameter.
     TDK_Incomplete,
     /// Template argument deduction did not deduce a value for every
     /// expansion of an expanded template parameter pack.
     TDK_IncompletePack,
     /// Template argument deduction produced inconsistent
     /// deduced values for the given template parameter.
     TDK_Inconsistent,
     /// Template argument deduction failed due to inconsistent
     /// cv-qualifiers on a template parameter type that would
     /// otherwise be deduced, e.g., we tried to deduce T in "const T"
     /// but were given a non-const "X".
     TDK_Underqualified,
     /// Substitution of the deduced template argument values
     /// resulted in an error.
     TDK_SubstitutionFailure,
     /// After substituting deduced template arguments, a dependent
     /// parameter type did not match the corresponding argument.
     TDK_DeducedMismatch,
     /// After substituting deduced template arguments, an element of
     /// a dependent parameter type did not match the corresponding element
     /// of the corresponding argument (when deducing from an initializer list).
     TDK_DeducedMismatchNested,
     /// A non-depnedent component of the parameter did not match the
     /// corresponding component of the argument.
     TDK_NonDeducedMismatch,
     /// When performing template argument deduction for a function
     /// template, there were too many call arguments.
     TDK_TooManyArguments,
     /// When performing template argument deduction for a function
     /// template, there were too few call arguments.
     TDK_TooFewArguments,
     /// The explicitly-specified template arguments were not valid
     /// template arguments for the given template.
     TDK_InvalidExplicitArguments,
     /// Checking non-dependent argument conversions failed.
     TDK_NonDependentConversionFailure,
     /// The deduced arguments did not satisfy the constraints associated
     /// with the template.
     TDK_ConstraintsNotSatisfied,
     /// Deduction failed; that's all we know.
     TDK_MiscellaneousDeductionFailure,
     /// CUDA Target attributes do not match.
     TDK_CUDATargetMismatch
   };
 
   TemplateDeductionResult
   DeduceTemplateArguments(ClassTemplatePartialSpecializationDecl *Partial,
                           const TemplateArgumentList &TemplateArgs,
                           sema::TemplateDeductionInfo &Info);
 
   TemplateDeductionResult
   DeduceTemplateArguments(VarTemplatePartialSpecializationDecl *Partial,
                           const TemplateArgumentList &TemplateArgs,
                           sema::TemplateDeductionInfo &Info);
 
   TemplateDeductionResult SubstituteExplicitTemplateArguments(
       FunctionTemplateDecl *FunctionTemplate,
       TemplateArgumentListInfo &ExplicitTemplateArgs,
       SmallVectorImpl<DeducedTemplateArgument> &Deduced,
       SmallVectorImpl<QualType> &ParamTypes, QualType *FunctionType,
       sema::TemplateDeductionInfo &Info);
 
   /// brief A function argument from which we performed template argument
   // deduction for a call.
   struct OriginalCallArg {
     OriginalCallArg(QualType OriginalParamType, bool DecomposedParam,
                     unsigned ArgIdx, QualType OriginalArgType)
         : OriginalParamType(OriginalParamType),
           DecomposedParam(DecomposedParam), ArgIdx(ArgIdx),
           OriginalArgType(OriginalArgType) {}
 
     QualType OriginalParamType;
     bool DecomposedParam;
     unsigned ArgIdx;
     QualType OriginalArgType;
   };
 
   TemplateDeductionResult FinishTemplateArgumentDeduction(
       FunctionTemplateDecl *FunctionTemplate,
       SmallVectorImpl<DeducedTemplateArgument> &Deduced,
       unsigned NumExplicitlySpecified, FunctionDecl *&Specialization,
       sema::TemplateDeductionInfo &Info,
       SmallVectorImpl<OriginalCallArg> const *OriginalCallArgs = nullptr,
       bool PartialOverloading = false,
       llvm::function_ref<bool()> CheckNonDependent = []{ return false; });
 
   TemplateDeductionResult DeduceTemplateArguments(
       FunctionTemplateDecl *FunctionTemplate,
       TemplateArgumentListInfo *ExplicitTemplateArgs, ArrayRef<Expr *> Args,
       FunctionDecl *&Specialization, sema::TemplateDeductionInfo &Info,
       bool PartialOverloading,
       llvm::function_ref<bool(ArrayRef<QualType>)> CheckNonDependent);
 
   TemplateDeductionResult
   DeduceTemplateArguments(FunctionTemplateDecl *FunctionTemplate,
                           TemplateArgumentListInfo *ExplicitTemplateArgs,
                           QualType ArgFunctionType,
                           FunctionDecl *&Specialization,
                           sema::TemplateDeductionInfo &Info,
                           bool IsAddressOfFunction = false);
 
   TemplateDeductionResult
   DeduceTemplateArguments(FunctionTemplateDecl *FunctionTemplate,
                           QualType ToType,
                           CXXConversionDecl *&Specialization,
                           sema::TemplateDeductionInfo &Info);
 
   TemplateDeductionResult
   DeduceTemplateArguments(FunctionTemplateDecl *FunctionTemplate,
                           TemplateArgumentListInfo *ExplicitTemplateArgs,
                           FunctionDecl *&Specialization,
                           sema::TemplateDeductionInfo &Info,
                           bool IsAddressOfFunction = false);
 
   /// Substitute Replacement for \p auto in \p TypeWithAuto
   QualType SubstAutoType(QualType TypeWithAuto, QualType Replacement);
   /// Substitute Replacement for auto in TypeWithAuto
   TypeSourceInfo* SubstAutoTypeSourceInfo(TypeSourceInfo *TypeWithAuto,
                                           QualType Replacement);
   /// Completely replace the \c auto in \p TypeWithAuto by
   /// \p Replacement. This does not retain any \c auto type sugar.
   QualType ReplaceAutoType(QualType TypeWithAuto, QualType Replacement);
 
   /// Result type of DeduceAutoType.
   enum DeduceAutoResult {
     DAR_Succeeded,
     DAR_Failed,
     DAR_FailedAlreadyDiagnosed
   };
 
   DeduceAutoResult
   DeduceAutoType(TypeSourceInfo *AutoType, Expr *&Initializer, QualType &Result,
                  Optional<unsigned> DependentDeductionDepth = None,
                  bool IgnoreConstraints = false);
   DeduceAutoResult
   DeduceAutoType(TypeLoc AutoTypeLoc, Expr *&Initializer, QualType &Result,
                  Optional<unsigned> DependentDeductionDepth = None,
                  bool IgnoreConstraints = false);
   void DiagnoseAutoDeductionFailure(VarDecl *VDecl, Expr *Init);
   bool DeduceReturnType(FunctionDecl *FD, SourceLocation Loc,
                         bool Diagnose = true);
 
   /// Declare implicit deduction guides for a class template if we've
   /// not already done so.
   void DeclareImplicitDeductionGuides(TemplateDecl *Template,
                                       SourceLocation Loc);
 
   QualType DeduceTemplateSpecializationFromInitializer(
       TypeSourceInfo *TInfo, const InitializedEntity &Entity,
       const InitializationKind &Kind, MultiExprArg Init);
 
   QualType deduceVarTypeFromInitializer(VarDecl *VDecl, DeclarationName Name,
                                         QualType Type, TypeSourceInfo *TSI,
                                         SourceRange Range, bool DirectInit,
                                         Expr *Init);
 
   TypeLoc getReturnTypeLoc(FunctionDecl *FD) const;
 
   bool DeduceFunctionTypeFromReturnExpr(FunctionDecl *FD,
                                         SourceLocation ReturnLoc,
                                         Expr *&RetExpr, AutoType *AT);
 
   FunctionTemplateDecl *getMoreSpecializedTemplate(
       FunctionTemplateDecl *FT1, FunctionTemplateDecl *FT2, SourceLocation Loc,
       TemplatePartialOrderingContext TPOC, unsigned NumCallArguments1,
       unsigned NumCallArguments2, bool Reversed = false);
   UnresolvedSetIterator
   getMostSpecialized(UnresolvedSetIterator SBegin, UnresolvedSetIterator SEnd,
                      TemplateSpecCandidateSet &FailedCandidates,
                      SourceLocation Loc,
                      const PartialDiagnostic &NoneDiag,
                      const PartialDiagnostic &AmbigDiag,
                      const PartialDiagnostic &CandidateDiag,
                      bool Complain = true, QualType TargetType = QualType());
 
   ClassTemplatePartialSpecializationDecl *
   getMoreSpecializedPartialSpecialization(
                                   ClassTemplatePartialSpecializationDecl *PS1,
                                   ClassTemplatePartialSpecializationDecl *PS2,
                                   SourceLocation Loc);
 
   bool isMoreSpecializedThanPrimary(ClassTemplatePartialSpecializationDecl *T,
                                     sema::TemplateDeductionInfo &Info);
 
   VarTemplatePartialSpecializationDecl *getMoreSpecializedPartialSpecialization(
       VarTemplatePartialSpecializationDecl *PS1,
       VarTemplatePartialSpecializationDecl *PS2, SourceLocation Loc);
 
   bool isMoreSpecializedThanPrimary(VarTemplatePartialSpecializationDecl *T,
                                     sema::TemplateDeductionInfo &Info);
 
   bool isTemplateTemplateParameterAtLeastAsSpecializedAs(
       TemplateParameterList *PParam, TemplateDecl *AArg, SourceLocation Loc);
 
   void MarkUsedTemplateParameters(const Expr *E, bool OnlyDeduced,
                                   unsigned Depth, llvm::SmallBitVector &Used);
 
   void MarkUsedTemplateParameters(const TemplateArgumentList &TemplateArgs,
                                   bool OnlyDeduced,
                                   unsigned Depth,
                                   llvm::SmallBitVector &Used);
   void MarkDeducedTemplateParameters(
                                   const FunctionTemplateDecl *FunctionTemplate,
                                   llvm::SmallBitVector &Deduced) {
     return MarkDeducedTemplateParameters(Context, FunctionTemplate, Deduced);
   }
   static void MarkDeducedTemplateParameters(ASTContext &Ctx,
                                   const FunctionTemplateDecl *FunctionTemplate,
                                   llvm::SmallBitVector &Deduced);
 
   //===--------------------------------------------------------------------===//
   // C++ Template Instantiation
   //
 
   MultiLevelTemplateArgumentList
   getTemplateInstantiationArgs(NamedDecl *D,
                                const TemplateArgumentList *Innermost = nullptr,
                                bool RelativeToPrimary = false,
                                const FunctionDecl *Pattern = nullptr);
 
   /// A context in which code is being synthesized (where a source location
   /// alone is not sufficient to identify the context). This covers template
   /// instantiation and various forms of implicitly-generated functions.
   struct CodeSynthesisContext {
     /// The kind of template instantiation we are performing
     enum SynthesisKind {
       /// We are instantiating a template declaration. The entity is
       /// the declaration we're instantiating (e.g., a CXXRecordDecl).
       TemplateInstantiation,
 
       /// We are instantiating a default argument for a template
       /// parameter. The Entity is the template parameter whose argument is
       /// being instantiated, the Template is the template, and the
       /// TemplateArgs/NumTemplateArguments provide the template arguments as
       /// specified.
       DefaultTemplateArgumentInstantiation,
 
       /// We are instantiating a default argument for a function.
       /// The Entity is the ParmVarDecl, and TemplateArgs/NumTemplateArgs
       /// provides the template arguments as specified.
       DefaultFunctionArgumentInstantiation,
 
       /// We are substituting explicit template arguments provided for
       /// a function template. The entity is a FunctionTemplateDecl.
       ExplicitTemplateArgumentSubstitution,
 
       /// We are substituting template argument determined as part of
       /// template argument deduction for either a class template
       /// partial specialization or a function template. The
       /// Entity is either a {Class|Var}TemplatePartialSpecializationDecl or
       /// a TemplateDecl.
       DeducedTemplateArgumentSubstitution,
 
       /// We are substituting prior template arguments into a new
       /// template parameter. The template parameter itself is either a
       /// NonTypeTemplateParmDecl or a TemplateTemplateParmDecl.
       PriorTemplateArgumentSubstitution,
 
       /// We are checking the validity of a default template argument that
       /// has been used when naming a template-id.
       DefaultTemplateArgumentChecking,
 
       /// We are computing the exception specification for a defaulted special
       /// member function.
       ExceptionSpecEvaluation,
 
       /// We are instantiating the exception specification for a function
       /// template which was deferred until it was needed.
       ExceptionSpecInstantiation,
 
       /// We are instantiating a requirement of a requires expression.
       RequirementInstantiation,
 
       /// We are checking the satisfaction of a nested requirement of a requires
       /// expression.
       NestedRequirementConstraintsCheck,
 
       /// We are declaring an implicit special member function.
       DeclaringSpecialMember,
 
       /// We are declaring an implicit 'operator==' for a defaulted
       /// 'operator<=>'.
       DeclaringImplicitEqualityComparison,
 
       /// We are defining a synthesized function (such as a defaulted special
       /// member).
       DefiningSynthesizedFunction,
 
       // We are checking the constraints associated with a constrained entity or
       // the constraint expression of a concept. This includes the checks that
       // atomic constraints have the type 'bool' and that they can be constant
       // evaluated.
       ConstraintsCheck,
 
       // We are substituting template arguments into a constraint expression.
       ConstraintSubstitution,
 
       // We are normalizing a constraint expression.
       ConstraintNormalization,
 
       // We are substituting into the parameter mapping of an atomic constraint
       // during normalization.
       ParameterMappingSubstitution,
 
       /// We are rewriting a comparison operator in terms of an operator<=>.
       RewritingOperatorAsSpaceship,
 
       /// Added for Template instantiation observation.
       /// Memoization means we are _not_ instantiating a template because
       /// it is already instantiated (but we entered a context where we
       /// would have had to if it was not already instantiated).
       Memoization
     } Kind;
 
     /// Was the enclosing context a non-instantiation SFINAE context?
     bool SavedInNonInstantiationSFINAEContext;
 
     /// The point of instantiation or synthesis within the source code.
     SourceLocation PointOfInstantiation;
 
     /// The entity that is being synthesized.
     Decl *Entity;
 
     /// The template (or partial specialization) in which we are
     /// performing the instantiation, for substitutions of prior template
     /// arguments.
     NamedDecl *Template;
 
     /// The list of template arguments we are substituting, if they
     /// are not part of the entity.
     const TemplateArgument *TemplateArgs;
 
     // FIXME: Wrap this union around more members, or perhaps store the
     // kind-specific members in the RAII object owning the context.
     union {
       /// The number of template arguments in TemplateArgs.
       unsigned NumTemplateArgs;
 
       /// The special member being declared or defined.
       CXXSpecialMember SpecialMember;
     };
 
     ArrayRef<TemplateArgument> template_arguments() const {
       assert(Kind != DeclaringSpecialMember);
       return {TemplateArgs, NumTemplateArgs};
     }
 
     /// The template deduction info object associated with the
     /// substitution or checking of explicit or deduced template arguments.
     sema::TemplateDeductionInfo *DeductionInfo;
 
     /// The source range that covers the construct that cause
     /// the instantiation, e.g., the template-id that causes a class
     /// template instantiation.
     SourceRange InstantiationRange;
 
     CodeSynthesisContext()
         : Kind(TemplateInstantiation),
           SavedInNonInstantiationSFINAEContext(false), Entity(nullptr),
           Template(nullptr), TemplateArgs(nullptr), NumTemplateArgs(0),
           DeductionInfo(nullptr) {}
 
     /// Determines whether this template is an actual instantiation
     /// that should be counted toward the maximum instantiation depth.
     bool isInstantiationRecord() const;
   };
 
   /// List of active code synthesis contexts.
   ///
   /// This vector is treated as a stack. As synthesis of one entity requires
   /// synthesis of another, additional contexts are pushed onto the stack.
   SmallVector<CodeSynthesisContext, 16> CodeSynthesisContexts;
 
   /// Specializations whose definitions are currently being instantiated.
   llvm::DenseSet<std::pair<Decl *, unsigned>> InstantiatingSpecializations;
 
   /// Non-dependent types used in templates that have already been instantiated
   /// by some template instantiation.
   llvm::DenseSet<QualType> InstantiatedNonDependentTypes;
 
   /// Extra modules inspected when performing a lookup during a template
   /// instantiation. Computed lazily.
   SmallVector<Module*, 16> CodeSynthesisContextLookupModules;
 
   /// Cache of additional modules that should be used for name lookup
   /// within the current template instantiation. Computed lazily; use
   /// getLookupModules() to get a complete set.
   llvm::DenseSet<Module*> LookupModulesCache;
 
   /// Get the set of additional modules that should be checked during
   /// name lookup. A module and its imports become visible when instanting a
   /// template defined within it.
   llvm::DenseSet<Module*> &getLookupModules();
 
   /// Map from the most recent declaration of a namespace to the most
   /// recent visible declaration of that namespace.
   llvm::DenseMap<NamedDecl*, NamedDecl*> VisibleNamespaceCache;
 
   /// Whether we are in a SFINAE context that is not associated with
   /// template instantiation.
   ///
   /// This is used when setting up a SFINAE trap (\c see SFINAETrap) outside
   /// of a template instantiation or template argument deduction.
   bool InNonInstantiationSFINAEContext;
 
   /// The number of \p CodeSynthesisContexts that are not template
   /// instantiations and, therefore, should not be counted as part of the
   /// instantiation depth.
   ///
   /// When the instantiation depth reaches the user-configurable limit
   /// \p LangOptions::InstantiationDepth we will abort instantiation.
   // FIXME: Should we have a similar limit for other forms of synthesis?
   unsigned NonInstantiationEntries;
 
   /// The depth of the context stack at the point when the most recent
   /// error or warning was produced.
   ///
   /// This value is used to suppress printing of redundant context stacks
   /// when there are multiple errors or warnings in the same instantiation.
   // FIXME: Does this belong in Sema? It's tough to implement it anywhere else.
   unsigned LastEmittedCodeSynthesisContextDepth = 0;
 
   /// The template instantiation callbacks to trace or track
   /// instantiations (objects can be chained).
   ///
   /// This callbacks is used to print, trace or track template
   /// instantiations as they are being constructed.
   std::vector<std::unique_ptr<TemplateInstantiationCallback>>
       TemplateInstCallbacks;
 
   /// The current index into pack expansion arguments that will be
   /// used for substitution of parameter packs.
   ///
   /// The pack expansion index will be -1 to indicate that parameter packs
   /// should be instantiated as themselves. Otherwise, the index specifies
   /// which argument within the parameter pack will be used for substitution.
   int ArgumentPackSubstitutionIndex;
 
   /// RAII object used to change the argument pack substitution index
   /// within a \c Sema object.
   ///
   /// See \c ArgumentPackSubstitutionIndex for more information.
   class ArgumentPackSubstitutionIndexRAII {
     Sema &Self;
     int OldSubstitutionIndex;
 
   public:
     ArgumentPackSubstitutionIndexRAII(Sema &Self, int NewSubstitutionIndex)
       : Self(Self), OldSubstitutionIndex(Self.ArgumentPackSubstitutionIndex) {
       Self.ArgumentPackSubstitutionIndex = NewSubstitutionIndex;
     }
 
     ~ArgumentPackSubstitutionIndexRAII() {
       Self.ArgumentPackSubstitutionIndex = OldSubstitutionIndex;
     }
   };
 
   friend class ArgumentPackSubstitutionRAII;
 
   /// For each declaration that involved template argument deduction, the
   /// set of diagnostics that were suppressed during that template argument
   /// deduction.
   ///
   /// FIXME: Serialize this structure to the AST file.
   typedef llvm::DenseMap<Decl *, SmallVector<PartialDiagnosticAt, 1> >
     SuppressedDiagnosticsMap;
   SuppressedDiagnosticsMap SuppressedDiagnostics;
 
   /// A stack object to be created when performing template
   /// instantiation.
   ///
   /// Construction of an object of type \c InstantiatingTemplate
   /// pushes the current instantiation onto the stack of active
   /// instantiations. If the size of this stack exceeds the maximum
   /// number of recursive template instantiations, construction
   /// produces an error and evaluates true.
   ///
   /// Destruction of this object will pop the named instantiation off
   /// the stack.
   struct InstantiatingTemplate {
     /// Note that we are instantiating a class template,
     /// function template, variable template, alias template,
     /// or a member thereof.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           Decl *Entity,
                           SourceRange InstantiationRange = SourceRange());
 
     struct ExceptionSpecification {};
     /// Note that we are instantiating an exception specification
     /// of a function template.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           FunctionDecl *Entity, ExceptionSpecification,
                           SourceRange InstantiationRange = SourceRange());
 
     /// Note that we are instantiating a default argument in a
     /// template-id.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           TemplateParameter Param, TemplateDecl *Template,
                           ArrayRef<TemplateArgument> TemplateArgs,
                           SourceRange InstantiationRange = SourceRange());
 
     /// Note that we are substituting either explicitly-specified or
     /// deduced template arguments during function template argument deduction.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           FunctionTemplateDecl *FunctionTemplate,
                           ArrayRef<TemplateArgument> TemplateArgs,
                           CodeSynthesisContext::SynthesisKind Kind,
                           sema::TemplateDeductionInfo &DeductionInfo,
                           SourceRange InstantiationRange = SourceRange());
 
     /// Note that we are instantiating as part of template
     /// argument deduction for a class template declaration.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           TemplateDecl *Template,
                           ArrayRef<TemplateArgument> TemplateArgs,
                           sema::TemplateDeductionInfo &DeductionInfo,
                           SourceRange InstantiationRange = SourceRange());
 
     /// Note that we are instantiating as part of template
     /// argument deduction for a class template partial
     /// specialization.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           ClassTemplatePartialSpecializationDecl *PartialSpec,
                           ArrayRef<TemplateArgument> TemplateArgs,
                           sema::TemplateDeductionInfo &DeductionInfo,
                           SourceRange InstantiationRange = SourceRange());
 
     /// Note that we are instantiating as part of template
     /// argument deduction for a variable template partial
     /// specialization.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           VarTemplatePartialSpecializationDecl *PartialSpec,
                           ArrayRef<TemplateArgument> TemplateArgs,
                           sema::TemplateDeductionInfo &DeductionInfo,
                           SourceRange InstantiationRange = SourceRange());
 
     /// Note that we are instantiating a default argument for a function
     /// parameter.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           ParmVarDecl *Param,
                           ArrayRef<TemplateArgument> TemplateArgs,
                           SourceRange InstantiationRange = SourceRange());
 
     /// Note that we are substituting prior template arguments into a
     /// non-type parameter.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           NamedDecl *Template,
                           NonTypeTemplateParmDecl *Param,
                           ArrayRef<TemplateArgument> TemplateArgs,
                           SourceRange InstantiationRange);
 
     /// Note that we are substituting prior template arguments into a
     /// template template parameter.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           NamedDecl *Template,
                           TemplateTemplateParmDecl *Param,
                           ArrayRef<TemplateArgument> TemplateArgs,
                           SourceRange InstantiationRange);
 
     /// Note that we are checking the default template argument
     /// against the template parameter for a given template-id.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           TemplateDecl *Template,
                           NamedDecl *Param,
                           ArrayRef<TemplateArgument> TemplateArgs,
                           SourceRange InstantiationRange);
 
     struct ConstraintsCheck {};
     /// \brief Note that we are checking the constraints associated with some
     /// constrained entity (a concept declaration or a template with associated
     /// constraints).
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           ConstraintsCheck, NamedDecl *Template,
                           ArrayRef<TemplateArgument> TemplateArgs,
                           SourceRange InstantiationRange);
 
     struct ConstraintSubstitution {};
     /// \brief Note that we are checking a constraint expression associated
     /// with a template declaration or as part of the satisfaction check of a
     /// concept.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           ConstraintSubstitution, NamedDecl *Template,
                           sema::TemplateDeductionInfo &DeductionInfo,
                           SourceRange InstantiationRange);
 
     struct ConstraintNormalization {};
     /// \brief Note that we are normalizing a constraint expression.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           ConstraintNormalization, NamedDecl *Template,
                           SourceRange InstantiationRange);
 
     struct ParameterMappingSubstitution {};
     /// \brief Note that we are subtituting into the parameter mapping of an
     /// atomic constraint during constraint normalization.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           ParameterMappingSubstitution, NamedDecl *Template,
                           SourceRange InstantiationRange);
 
     /// \brief Note that we are substituting template arguments into a part of
     /// a requirement of a requires expression.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           concepts::Requirement *Req,
                           sema::TemplateDeductionInfo &DeductionInfo,
                           SourceRange InstantiationRange = SourceRange());
 
     /// \brief Note that we are checking the satisfaction of the constraint
     /// expression inside of a nested requirement.
     InstantiatingTemplate(Sema &SemaRef, SourceLocation PointOfInstantiation,
                           concepts::NestedRequirement *Req, ConstraintsCheck,
                           SourceRange InstantiationRange = SourceRange());
 
     /// Note that we have finished instantiating this template.
     void Clear();
 
     ~InstantiatingTemplate() { Clear(); }
 
     /// Determines whether we have exceeded the maximum
     /// recursive template instantiations.
     bool isInvalid() const { return Invalid; }
 
     /// Determine whether we are already instantiating this
     /// specialization in some surrounding active instantiation.
     bool isAlreadyInstantiating() const { return AlreadyInstantiating; }
 
   private:
     Sema &SemaRef;
     bool Invalid;
     bool AlreadyInstantiating;
     bool CheckInstantiationDepth(SourceLocation PointOfInstantiation,
                                  SourceRange InstantiationRange);
 
     InstantiatingTemplate(
         Sema &SemaRef, CodeSynthesisContext::SynthesisKind Kind,
         SourceLocation PointOfInstantiation, SourceRange InstantiationRange,
         Decl *Entity, NamedDecl *Template = nullptr,
         ArrayRef<TemplateArgument> TemplateArgs = None,
         sema::TemplateDeductionInfo *DeductionInfo = nullptr);
 
     InstantiatingTemplate(const InstantiatingTemplate&) = delete;
 
     InstantiatingTemplate&
     operator=(const InstantiatingTemplate&) = delete;
   };
 
   void pushCodeSynthesisContext(CodeSynthesisContext Ctx);
   void popCodeSynthesisContext();
 
   /// Determine whether we are currently performing template instantiation.
   bool inTemplateInstantiation() const {
     return CodeSynthesisContexts.size() > NonInstantiationEntries;
   }
 
   void PrintContextStack() {
     if (!CodeSynthesisContexts.empty() &&
         CodeSynthesisContexts.size() != LastEmittedCodeSynthesisContextDepth) {
       PrintInstantiationStack();
       LastEmittedCodeSynthesisContextDepth = CodeSynthesisContexts.size();
     }
     if (PragmaAttributeCurrentTargetDecl)
       PrintPragmaAttributeInstantiationPoint();
   }
   void PrintInstantiationStack();
 
   void PrintPragmaAttributeInstantiationPoint();
 
   /// Determines whether we are currently in a context where
   /// template argument substitution failures are not considered
   /// errors.
   ///
   /// \returns An empty \c Optional if we're not in a SFINAE context.
   /// Otherwise, contains a pointer that, if non-NULL, contains the nearest
   /// template-deduction context object, which can be used to capture
   /// diagnostics that will be suppressed.
   Optional<sema::TemplateDeductionInfo *> isSFINAEContext() const;
 
   /// Determines whether we are currently in a context that
   /// is not evaluated as per C++ [expr] p5.
   bool isUnevaluatedContext() const {
     assert(!ExprEvalContexts.empty() &&
            "Must be in an expression evaluation context");
     return ExprEvalContexts.back().isUnevaluated();
   }
 
   /// RAII class used to determine whether SFINAE has
   /// trapped any errors that occur during template argument
   /// deduction.
   class SFINAETrap {
     Sema &SemaRef;
     unsigned PrevSFINAEErrors;
     bool PrevInNonInstantiationSFINAEContext;
     bool PrevAccessCheckingSFINAE;
     bool PrevLastDiagnosticIgnored;
 
   public:
     explicit SFINAETrap(Sema &SemaRef, bool AccessCheckingSFINAE = false)
       : SemaRef(SemaRef), PrevSFINAEErrors(SemaRef.NumSFINAEErrors),
         PrevInNonInstantiationSFINAEContext(
                                       SemaRef.InNonInstantiationSFINAEContext),
         PrevAccessCheckingSFINAE(SemaRef.AccessCheckingSFINAE),
         PrevLastDiagnosticIgnored(
             SemaRef.getDiagnostics().isLastDiagnosticIgnored())
     {
       if (!SemaRef.isSFINAEContext())
         SemaRef.InNonInstantiationSFINAEContext = true;
       SemaRef.AccessCheckingSFINAE = AccessCheckingSFINAE;
     }
 
     ~SFINAETrap() {
       SemaRef.NumSFINAEErrors = PrevSFINAEErrors;
       SemaRef.InNonInstantiationSFINAEContext
         = PrevInNonInstantiationSFINAEContext;
       SemaRef.AccessCheckingSFINAE = PrevAccessCheckingSFINAE;
       SemaRef.getDiagnostics().setLastDiagnosticIgnored(
           PrevLastDiagnosticIgnored);
     }
 
     /// Determine whether any SFINAE errors have been trapped.
     bool hasErrorOccurred() const {
       return SemaRef.NumSFINAEErrors > PrevSFINAEErrors;
     }
   };
 
   /// RAII class used to indicate that we are performing provisional
   /// semantic analysis to determine the validity of a construct, so
   /// typo-correction and diagnostics in the immediate context (not within
   /// implicitly-instantiated templates) should be suppressed.
   class TentativeAnalysisScope {
     Sema &SemaRef;
     // FIXME: Using a SFINAETrap for this is a hack.
     SFINAETrap Trap;
     bool PrevDisableTypoCorrection;
   public:
     explicit TentativeAnalysisScope(Sema &SemaRef)
         : SemaRef(SemaRef), Trap(SemaRef, true),
           PrevDisableTypoCorrection(SemaRef.DisableTypoCorrection) {
       SemaRef.DisableTypoCorrection = true;
     }
     ~TentativeAnalysisScope() {
       SemaRef.DisableTypoCorrection = PrevDisableTypoCorrection;
     }
   };
 
   /// The current instantiation scope used to store local
   /// variables.
   LocalInstantiationScope *CurrentInstantiationScope;
 
   /// Tracks whether we are in a context where typo correction is
   /// disabled.
   bool DisableTypoCorrection;
 
   /// The number of typos corrected by CorrectTypo.
   unsigned TyposCorrected;
 
   typedef llvm::SmallSet<SourceLocation, 2> SrcLocSet;
   typedef llvm::DenseMap<IdentifierInfo *, SrcLocSet> IdentifierSourceLocations;
 
   /// A cache containing identifiers for which typo correction failed and
   /// their locations, so that repeated attempts to correct an identifier in a
   /// given location are ignored if typo correction already failed for it.
   IdentifierSourceLocations TypoCorrectionFailures;
 
   /// Worker object for performing CFG-based warnings.
   sema::AnalysisBasedWarnings AnalysisWarnings;
   threadSafety::BeforeSet *ThreadSafetyDeclCache;
 
   /// An entity for which implicit template instantiation is required.
   ///
   /// The source location associated with the declaration is the first place in
   /// the source code where the declaration was "used". It is not necessarily
   /// the point of instantiation (which will be either before or after the
   /// namespace-scope declaration that triggered this implicit instantiation),
   /// However, it is the location that diagnostics should generally refer to,
   /// because users will need to know what code triggered the instantiation.
   typedef std::pair<ValueDecl *, SourceLocation> PendingImplicitInstantiation;
 
   /// The queue of implicit template instantiations that are required
   /// but have not yet been performed.
   std::deque<PendingImplicitInstantiation> PendingInstantiations;
 
   /// Queue of implicit template instantiations that cannot be performed
   /// eagerly.
   SmallVector<PendingImplicitInstantiation, 1> LateParsedInstantiations;
 
   class GlobalEagerInstantiationScope {
   public:
     GlobalEagerInstantiationScope(Sema &S, bool Enabled)
         : S(S), Enabled(Enabled) {
       if (!Enabled) return;
 
       SavedPendingInstantiations.swap(S.PendingInstantiations);
       SavedVTableUses.swap(S.VTableUses);
     }
 
     void perform() {
       if (Enabled) {
         S.DefineUsedVTables();
         S.PerformPendingInstantiations();
       }
     }
 
     ~GlobalEagerInstantiationScope() {
       if (!Enabled) return;
 
       // Restore the set of pending vtables.
       assert(S.VTableUses.empty() &&
              "VTableUses should be empty before it is discarded.");
       S.VTableUses.swap(SavedVTableUses);
 
       // Restore the set of pending implicit instantiations.
       assert(S.PendingInstantiations.empty() &&
              "PendingInstantiations should be empty before it is discarded.");
       S.PendingInstantiations.swap(SavedPendingInstantiations);
     }
 
   private:
     Sema &S;
     SmallVector<VTableUse, 16> SavedVTableUses;
     std::deque<PendingImplicitInstantiation> SavedPendingInstantiations;
     bool Enabled;
   };
 
   /// The queue of implicit template instantiations that are required
   /// and must be performed within the current local scope.
   ///
   /// This queue is only used for member functions of local classes in
   /// templates, which must be instantiated in the same scope as their
   /// enclosing function, so that they can reference function-local
   /// types, static variables, enumerators, etc.
   std::deque<PendingImplicitInstantiation> PendingLocalImplicitInstantiations;
 
   class LocalEagerInstantiationScope {
   public:
     LocalEagerInstantiationScope(Sema &S) : S(S) {
       SavedPendingLocalImplicitInstantiations.swap(
           S.PendingLocalImplicitInstantiations);
     }
 
     void perform() { S.PerformPendingInstantiations(/*LocalOnly=*/true); }
 
     ~LocalEagerInstantiationScope() {
       assert(S.PendingLocalImplicitInstantiations.empty() &&
              "there shouldn't be any pending local implicit instantiations");
       SavedPendingLocalImplicitInstantiations.swap(
           S.PendingLocalImplicitInstantiations);
     }
 
   private:
     Sema &S;
     std::deque<PendingImplicitInstantiation>
         SavedPendingLocalImplicitInstantiations;
   };
 
   /// A helper class for building up ExtParameterInfos.
   class ExtParameterInfoBuilder {
     SmallVector<FunctionProtoType::ExtParameterInfo, 16> Infos;
     bool HasInteresting = false;
 
   public:
     /// Set the ExtParameterInfo for the parameter at the given index,
     ///
     void set(unsigned index, FunctionProtoType::ExtParameterInfo info) {
       assert(Infos.size() <= index);
       Infos.resize(index);
       Infos.push_back(info);
 
       if (!HasInteresting)
         HasInteresting = (info != FunctionProtoType::ExtParameterInfo());
     }
 
     /// Return a pointer (suitable for setting in an ExtProtoInfo) to the
     /// ExtParameterInfo array we've built up.
     const FunctionProtoType::ExtParameterInfo *
     getPointerOrNull(unsigned numParams) {
       if (!HasInteresting) return nullptr;
       Infos.resize(numParams);
       return Infos.data();
     }
   };
 
   void PerformPendingInstantiations(bool LocalOnly = false);
 
   TypeSourceInfo *SubstType(TypeSourceInfo *T,
                             const MultiLevelTemplateArgumentList &TemplateArgs,
                             SourceLocation Loc, DeclarationName Entity,
                             bool AllowDeducedTST = false);
 
   QualType SubstType(QualType T,
                      const MultiLevelTemplateArgumentList &TemplateArgs,
                      SourceLocation Loc, DeclarationName Entity);
 
   TypeSourceInfo *SubstType(TypeLoc TL,
                             const MultiLevelTemplateArgumentList &TemplateArgs,
                             SourceLocation Loc, DeclarationName Entity);
 
   TypeSourceInfo *SubstFunctionDeclType(TypeSourceInfo *T,
                             const MultiLevelTemplateArgumentList &TemplateArgs,
                                         SourceLocation Loc,
                                         DeclarationName Entity,
                                         CXXRecordDecl *ThisContext,
                                         Qualifiers ThisTypeQuals);
   void SubstExceptionSpec(FunctionDecl *New, const FunctionProtoType *Proto,
                           const MultiLevelTemplateArgumentList &Args);
   bool SubstExceptionSpec(SourceLocation Loc,
                           FunctionProtoType::ExceptionSpecInfo &ESI,
                           SmallVectorImpl<QualType> &ExceptionStorage,
                           const MultiLevelTemplateArgumentList &Args);
   ParmVarDecl *SubstParmVarDecl(ParmVarDecl *D,
                             const MultiLevelTemplateArgumentList &TemplateArgs,
                                 int indexAdjustment,
                                 Optional<unsigned> NumExpansions,
                                 bool ExpectParameterPack);
   bool SubstParmTypes(SourceLocation Loc, ArrayRef<ParmVarDecl *> Params,
                       const FunctionProtoType::ExtParameterInfo *ExtParamInfos,
                       const MultiLevelTemplateArgumentList &TemplateArgs,
                       SmallVectorImpl<QualType> &ParamTypes,
                       SmallVectorImpl<ParmVarDecl *> *OutParams,
                       ExtParameterInfoBuilder &ParamInfos);
   ExprResult SubstExpr(Expr *E,
                        const MultiLevelTemplateArgumentList &TemplateArgs);
 
   /// Substitute the given template arguments into a list of
   /// expressions, expanding pack expansions if required.
   ///
   /// \param Exprs The list of expressions to substitute into.
   ///
   /// \param IsCall Whether this is some form of call, in which case
   /// default arguments will be dropped.
   ///
   /// \param TemplateArgs The set of template arguments to substitute.
   ///
   /// \param Outputs Will receive all of the substituted arguments.
   ///
   /// \returns true if an error occurred, false otherwise.
   bool SubstExprs(ArrayRef<Expr *> Exprs, bool IsCall,
                   const MultiLevelTemplateArgumentList &TemplateArgs,
                   SmallVectorImpl<Expr *> &Outputs);
 
   StmtResult SubstStmt(Stmt *S,
                        const MultiLevelTemplateArgumentList &TemplateArgs);
 
   TemplateParameterList *
   SubstTemplateParams(TemplateParameterList *Params, DeclContext *Owner,
                       const MultiLevelTemplateArgumentList &TemplateArgs);
 
   bool
   SubstTemplateArguments(ArrayRef<TemplateArgumentLoc> Args,
                          const MultiLevelTemplateArgumentList &TemplateArgs,
                          TemplateArgumentListInfo &Outputs);
 
 
   Decl *SubstDecl(Decl *D, DeclContext *Owner,
                   const MultiLevelTemplateArgumentList &TemplateArgs);
 
   /// Substitute the name and return type of a defaulted 'operator<=>' to form
   /// an implicit 'operator=='.
   FunctionDecl *SubstSpaceshipAsEqualEqual(CXXRecordDecl *RD,
                                            FunctionDecl *Spaceship);
 
   ExprResult SubstInitializer(Expr *E,
                        const MultiLevelTemplateArgumentList &TemplateArgs,
                        bool CXXDirectInit);
 
   bool
   SubstBaseSpecifiers(CXXRecordDecl *Instantiation,
                       CXXRecordDecl *Pattern,
                       const MultiLevelTemplateArgumentList &TemplateArgs);
 
   bool
   InstantiateClass(SourceLocation PointOfInstantiation,
                    CXXRecordDecl *Instantiation, CXXRecordDecl *Pattern,
                    const MultiLevelTemplateArgumentList &TemplateArgs,
                    TemplateSpecializationKind TSK,
                    bool Complain = true);
 
   bool InstantiateEnum(SourceLocation PointOfInstantiation,
                        EnumDecl *Instantiation, EnumDecl *Pattern,
                        const MultiLevelTemplateArgumentList &TemplateArgs,
                        TemplateSpecializationKind TSK);
 
   bool InstantiateInClassInitializer(
       SourceLocation PointOfInstantiation, FieldDecl *Instantiation,
       FieldDecl *Pattern, const MultiLevelTemplateArgumentList &TemplateArgs);
 
   struct LateInstantiatedAttribute {
     const Attr *TmplAttr;
     LocalInstantiationScope *Scope;
     Decl *NewDecl;
 
     LateInstantiatedAttribute(const Attr *A, LocalInstantiationScope *S,
                               Decl *D)
       : TmplAttr(A), Scope(S), NewDecl(D)
     { }
   };
   typedef SmallVector<LateInstantiatedAttribute, 16> LateInstantiatedAttrVec;
 
   void InstantiateAttrs(const MultiLevelTemplateArgumentList &TemplateArgs,
                         const Decl *Pattern, Decl *Inst,
                         LateInstantiatedAttrVec *LateAttrs = nullptr,
                         LocalInstantiationScope *OuterMostScope = nullptr);
 
   void
   InstantiateAttrsForDecl(const MultiLevelTemplateArgumentList &TemplateArgs,
                           const Decl *Pattern, Decl *Inst,
                           LateInstantiatedAttrVec *LateAttrs = nullptr,
                           LocalInstantiationScope *OuterMostScope = nullptr);
 
   bool usesPartialOrExplicitSpecialization(
       SourceLocation Loc, ClassTemplateSpecializationDecl *ClassTemplateSpec);
 
   bool
   InstantiateClassTemplateSpecialization(SourceLocation PointOfInstantiation,
                            ClassTemplateSpecializationDecl *ClassTemplateSpec,
                            TemplateSpecializationKind TSK,
                            bool Complain = true);
 
   void InstantiateClassMembers(SourceLocation PointOfInstantiation,
                                CXXRecordDecl *Instantiation,
                             const MultiLevelTemplateArgumentList &TemplateArgs,
                                TemplateSpecializationKind TSK);
 
   void InstantiateClassTemplateSpecializationMembers(
                                           SourceLocation PointOfInstantiation,
                            ClassTemplateSpecializationDecl *ClassTemplateSpec,
                                                 TemplateSpecializationKind TSK);
 
   NestedNameSpecifierLoc
   SubstNestedNameSpecifierLoc(NestedNameSpecifierLoc NNS,
                            const MultiLevelTemplateArgumentList &TemplateArgs);
 
   DeclarationNameInfo
   SubstDeclarationNameInfo(const DeclarationNameInfo &NameInfo,
                            const MultiLevelTemplateArgumentList &TemplateArgs);
   TemplateName
   SubstTemplateName(NestedNameSpecifierLoc QualifierLoc, TemplateName Name,
                     SourceLocation Loc,
                     const MultiLevelTemplateArgumentList &TemplateArgs);
   bool Subst(const TemplateArgumentLoc *Args, unsigned NumArgs,
              TemplateArgumentListInfo &Result,
              const MultiLevelTemplateArgumentList &TemplateArgs);
 
   void InstantiateExceptionSpec(SourceLocation PointOfInstantiation,
                                 FunctionDecl *Function);
   bool CheckInstantiatedFunctionTemplateConstraints(
       SourceLocation PointOfInstantiation, FunctionDecl *Decl,
       ArrayRef<TemplateArgument> TemplateArgs,
       ConstraintSatisfaction &Satisfaction);
   FunctionDecl *InstantiateFunctionDeclaration(FunctionTemplateDecl *FTD,
                                                const TemplateArgumentList *Args,
                                                SourceLocation Loc);
   void InstantiateFunctionDefinition(SourceLocation PointOfInstantiation,
                                      FunctionDecl *Function,
                                      bool Recursive = false,
                                      bool DefinitionRequired = false,
                                      bool AtEndOfTU = false);
   VarTemplateSpecializationDecl *BuildVarTemplateInstantiation(
       VarTemplateDecl *VarTemplate, VarDecl *FromVar,
       const TemplateArgumentList &TemplateArgList,
       const TemplateArgumentListInfo &TemplateArgsInfo,
       SmallVectorImpl<TemplateArgument> &Converted,
       SourceLocation PointOfInstantiation, void *InsertPos,
       LateInstantiatedAttrVec *LateAttrs = nullptr,
       LocalInstantiationScope *StartingScope = nullptr);
   VarTemplateSpecializationDecl *CompleteVarTemplateSpecializationDecl(
       VarTemplateSpecializationDecl *VarSpec, VarDecl *PatternDecl,
       const MultiLevelTemplateArgumentList &TemplateArgs);
   void
   BuildVariableInstantiation(VarDecl *NewVar, VarDecl *OldVar,
                              const MultiLevelTemplateArgumentList &TemplateArgs,
                              LateInstantiatedAttrVec *LateAttrs,
                              DeclContext *Owner,
                              LocalInstantiationScope *StartingScope,
                              bool InstantiatingVarTemplate = false,
                              VarTemplateSpecializationDecl *PrevVTSD = nullptr);
 
   VarDecl *getVarTemplateSpecialization(
       VarTemplateDecl *VarTempl, const TemplateArgumentListInfo *TemplateArgs,
       const DeclarationNameInfo &MemberNameInfo, SourceLocation TemplateKWLoc);
 
   void InstantiateVariableInitializer(
       VarDecl *Var, VarDecl *OldVar,
       const MultiLevelTemplateArgumentList &TemplateArgs);
   void InstantiateVariableDefinition(SourceLocation PointOfInstantiation,
                                      VarDecl *Var, bool Recursive = false,
                                      bool DefinitionRequired = false,
                                      bool AtEndOfTU = false);
 
   void InstantiateMemInitializers(CXXConstructorDecl *New,
                                   const CXXConstructorDecl *Tmpl,
                             const MultiLevelTemplateArgumentList &TemplateArgs);
 
   NamedDecl *FindInstantiatedDecl(SourceLocation Loc, NamedDecl *D,
                           const MultiLevelTemplateArgumentList &TemplateArgs,
                           bool FindingInstantiatedContext = false);
   DeclContext *FindInstantiatedContext(SourceLocation Loc, DeclContext *DC,
                           const MultiLevelTemplateArgumentList &TemplateArgs);
 
   // Objective-C declarations.
   enum ObjCContainerKind {
     OCK_None = -1,
     OCK_Interface = 0,
     OCK_Protocol,
     OCK_Category,
     OCK_ClassExtension,
     OCK_Implementation,
     OCK_CategoryImplementation
   };
   ObjCContainerKind getObjCContainerKind() const;
 
   DeclResult actOnObjCTypeParam(Scope *S,
                                 ObjCTypeParamVariance variance,
                                 SourceLocation varianceLoc,
                                 unsigned index,
                                 IdentifierInfo *paramName,
                                 SourceLocation paramLoc,
                                 SourceLocation colonLoc,
                                 ParsedType typeBound);
 
   ObjCTypeParamList *actOnObjCTypeParamList(Scope *S, SourceLocation lAngleLoc,
                                             ArrayRef<Decl *> typeParams,
                                             SourceLocation rAngleLoc);
   void popObjCTypeParamList(Scope *S, ObjCTypeParamList *typeParamList);
 
   Decl *ActOnStartClassInterface(
       Scope *S, SourceLocation AtInterfaceLoc, IdentifierInfo *ClassName,
       SourceLocation ClassLoc, ObjCTypeParamList *typeParamList,
       IdentifierInfo *SuperName, SourceLocation SuperLoc,
       ArrayRef<ParsedType> SuperTypeArgs, SourceRange SuperTypeArgsRange,
       Decl *const *ProtoRefs, unsigned NumProtoRefs,
       const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc,
       const ParsedAttributesView &AttrList);
 
   void ActOnSuperClassOfClassInterface(Scope *S,
                                        SourceLocation AtInterfaceLoc,
                                        ObjCInterfaceDecl *IDecl,
                                        IdentifierInfo *ClassName,
                                        SourceLocation ClassLoc,
                                        IdentifierInfo *SuperName,
                                        SourceLocation SuperLoc,
                                        ArrayRef<ParsedType> SuperTypeArgs,
                                        SourceRange SuperTypeArgsRange);
 
   void ActOnTypedefedProtocols(SmallVectorImpl<Decl *> &ProtocolRefs,
                                SmallVectorImpl<SourceLocation> &ProtocolLocs,
                                IdentifierInfo *SuperName,
                                SourceLocation SuperLoc);
 
   Decl *ActOnCompatibilityAlias(
                     SourceLocation AtCompatibilityAliasLoc,
                     IdentifierInfo *AliasName,  SourceLocation AliasLocation,
                     IdentifierInfo *ClassName, SourceLocation ClassLocation);
 
   bool CheckForwardProtocolDeclarationForCircularDependency(
     IdentifierInfo *PName,
     SourceLocation &PLoc, SourceLocation PrevLoc,
     const ObjCList<ObjCProtocolDecl> &PList);
 
   Decl *ActOnStartProtocolInterface(
       SourceLocation AtProtoInterfaceLoc, IdentifierInfo *ProtocolName,
       SourceLocation ProtocolLoc, Decl *const *ProtoRefNames,
       unsigned NumProtoRefs, const SourceLocation *ProtoLocs,
       SourceLocation EndProtoLoc, const ParsedAttributesView &AttrList);
 
   Decl *ActOnStartCategoryInterface(
       SourceLocation AtInterfaceLoc, IdentifierInfo *ClassName,
       SourceLocation ClassLoc, ObjCTypeParamList *typeParamList,
       IdentifierInfo *CategoryName, SourceLocation CategoryLoc,
       Decl *const *ProtoRefs, unsigned NumProtoRefs,
       const SourceLocation *ProtoLocs, SourceLocation EndProtoLoc,
       const ParsedAttributesView &AttrList);
 
   Decl *ActOnStartClassImplementation(SourceLocation AtClassImplLoc,
                                       IdentifierInfo *ClassName,
                                       SourceLocation ClassLoc,
                                       IdentifierInfo *SuperClassname,
                                       SourceLocation SuperClassLoc,
                                       const ParsedAttributesView &AttrList);
 
   Decl *ActOnStartCategoryImplementation(SourceLocation AtCatImplLoc,
                                          IdentifierInfo *ClassName,
                                          SourceLocation ClassLoc,
                                          IdentifierInfo *CatName,
                                          SourceLocation CatLoc,
                                          const ParsedAttributesView &AttrList);
 
   DeclGroupPtrTy ActOnFinishObjCImplementation(Decl *ObjCImpDecl,
                                                ArrayRef<Decl *> Decls);
 
   DeclGroupPtrTy ActOnForwardClassDeclaration(SourceLocation Loc,
                    IdentifierInfo **IdentList,
                    SourceLocation *IdentLocs,
                    ArrayRef<ObjCTypeParamList *> TypeParamLists,
                    unsigned NumElts);
 
   DeclGroupPtrTy
   ActOnForwardProtocolDeclaration(SourceLocation AtProtoclLoc,
                                   ArrayRef<IdentifierLocPair> IdentList,
                                   const ParsedAttributesView &attrList);
 
   void FindProtocolDeclaration(bool WarnOnDeclarations, bool ForObjCContainer,
                                ArrayRef<IdentifierLocPair> ProtocolId,
                                SmallVectorImpl<Decl *> &Protocols);
 
   void DiagnoseTypeArgsAndProtocols(IdentifierInfo *ProtocolId,
                                     SourceLocation ProtocolLoc,
                                     IdentifierInfo *TypeArgId,
                                     SourceLocation TypeArgLoc,
                                     bool SelectProtocolFirst = false);
 
   /// Given a list of identifiers (and their locations), resolve the
   /// names to either Objective-C protocol qualifiers or type
   /// arguments, as appropriate.
   void actOnObjCTypeArgsOrProtocolQualifiers(
          Scope *S,
          ParsedType baseType,
          SourceLocation lAngleLoc,
          ArrayRef<IdentifierInfo *> identifiers,
          ArrayRef<SourceLocation> identifierLocs,
          SourceLocation rAngleLoc,
          SourceLocation &typeArgsLAngleLoc,
          SmallVectorImpl<ParsedType> &typeArgs,
          SourceLocation &typeArgsRAngleLoc,
          SourceLocation &protocolLAngleLoc,
          SmallVectorImpl<Decl *> &protocols,
          SourceLocation &protocolRAngleLoc,
          bool warnOnIncompleteProtocols);
 
   /// Build a an Objective-C protocol-qualified 'id' type where no
   /// base type was specified.
   TypeResult actOnObjCProtocolQualifierType(
                SourceLocation lAngleLoc,
                ArrayRef<Decl *> protocols,
                ArrayRef<SourceLocation> protocolLocs,
                SourceLocation rAngleLoc);
 
   /// Build a specialized and/or protocol-qualified Objective-C type.
   TypeResult actOnObjCTypeArgsAndProtocolQualifiers(
                Scope *S,
                SourceLocation Loc,
                ParsedType BaseType,
                SourceLocation TypeArgsLAngleLoc,
                ArrayRef<ParsedType> TypeArgs,
                SourceLocation TypeArgsRAngleLoc,
                SourceLocation ProtocolLAngleLoc,
                ArrayRef<Decl *> Protocols,
                ArrayRef<SourceLocation> ProtocolLocs,
                SourceLocation ProtocolRAngleLoc);
 
   /// Build an Objective-C type parameter type.
   QualType BuildObjCTypeParamType(const ObjCTypeParamDecl *Decl,
                                   SourceLocation ProtocolLAngleLoc,
                                   ArrayRef<ObjCProtocolDecl *> Protocols,
                                   ArrayRef<SourceLocation> ProtocolLocs,
                                   SourceLocation ProtocolRAngleLoc,
                                   bool FailOnError = false);
 
   /// Build an Objective-C object pointer type.
   QualType BuildObjCObjectType(QualType BaseType,
                                SourceLocation Loc,
                                SourceLocation TypeArgsLAngleLoc,
                                ArrayRef<TypeSourceInfo *> TypeArgs,
                                SourceLocation TypeArgsRAngleLoc,
                                SourceLocation ProtocolLAngleLoc,
                                ArrayRef<ObjCProtocolDecl *> Protocols,
                                ArrayRef<SourceLocation> ProtocolLocs,
                                SourceLocation ProtocolRAngleLoc,
                                bool FailOnError = false);
 
   /// Ensure attributes are consistent with type.
   /// \param [in, out] Attributes The attributes to check; they will
   /// be modified to be consistent with \p PropertyTy.
   void CheckObjCPropertyAttributes(Decl *PropertyPtrTy,
                                    SourceLocation Loc,
                                    unsigned &Attributes,
                                    bool propertyInPrimaryClass);
 
   /// Process the specified property declaration and create decls for the
   /// setters and getters as needed.
   /// \param property The property declaration being processed
   void ProcessPropertyDecl(ObjCPropertyDecl *property);
 
 
   void DiagnosePropertyMismatch(ObjCPropertyDecl *Property,
                                 ObjCPropertyDecl *SuperProperty,
                                 const IdentifierInfo *Name,
                                 bool OverridingProtocolProperty);
 
   void DiagnoseClassExtensionDupMethods(ObjCCategoryDecl *CAT,
                                         ObjCInterfaceDecl *ID);
 
   Decl *ActOnAtEnd(Scope *S, SourceRange AtEnd,
                    ArrayRef<Decl *> allMethods = None,
                    ArrayRef<DeclGroupPtrTy> allTUVars = None);
 
   Decl *ActOnProperty(Scope *S, SourceLocation AtLoc,
                       SourceLocation LParenLoc,
                       FieldDeclarator &FD, ObjCDeclSpec &ODS,
                       Selector GetterSel, Selector SetterSel,
                       tok::ObjCKeywordKind MethodImplKind,
                       DeclContext *lexicalDC = nullptr);
 
   Decl *ActOnPropertyImplDecl(Scope *S,
                               SourceLocation AtLoc,
                               SourceLocation PropertyLoc,
                               bool ImplKind,
                               IdentifierInfo *PropertyId,
                               IdentifierInfo *PropertyIvar,
                               SourceLocation PropertyIvarLoc,
                               ObjCPropertyQueryKind QueryKind);
 
   enum ObjCSpecialMethodKind {
     OSMK_None,
     OSMK_Alloc,
     OSMK_New,
     OSMK_Copy,
     OSMK_RetainingInit,
     OSMK_NonRetainingInit
   };
 
   struct ObjCArgInfo {
     IdentifierInfo *Name;
     SourceLocation NameLoc;
     // The Type is null if no type was specified, and the DeclSpec is invalid
     // in this case.
     ParsedType Type;
     ObjCDeclSpec DeclSpec;
 
     /// ArgAttrs - Attribute list for this argument.
     ParsedAttributesView ArgAttrs;
   };
 
   Decl *ActOnMethodDeclaration(
       Scope *S,
       SourceLocation BeginLoc, // location of the + or -.
       SourceLocation EndLoc,   // location of the ; or {.
       tok::TokenKind MethodType, ObjCDeclSpec &ReturnQT, ParsedType ReturnType,
       ArrayRef<SourceLocation> SelectorLocs, Selector Sel,
       // optional arguments. The number of types/arguments is obtained
       // from the Sel.getNumArgs().
       ObjCArgInfo *ArgInfo, DeclaratorChunk::ParamInfo *CParamInfo,
       unsigned CNumArgs, // c-style args
       const ParsedAttributesView &AttrList, tok::ObjCKeywordKind MethodImplKind,
       bool isVariadic, bool MethodDefinition);
 
   ObjCMethodDecl *LookupMethodInQualifiedType(Selector Sel,
                                               const ObjCObjectPointerType *OPT,
                                               bool IsInstance);
   ObjCMethodDecl *LookupMethodInObjectType(Selector Sel, QualType Ty,
                                            bool IsInstance);
 
   bool CheckARCMethodDecl(ObjCMethodDecl *method);
   bool inferObjCARCLifetime(ValueDecl *decl);
 
   void deduceOpenCLAddressSpace(ValueDecl *decl);
 
   ExprResult
   HandleExprPropertyRefExpr(const ObjCObjectPointerType *OPT,
                             Expr *BaseExpr,
                             SourceLocation OpLoc,
                             DeclarationName MemberName,
                             SourceLocation MemberLoc,
                             SourceLocation SuperLoc, QualType SuperType,
                             bool Super);
 
   ExprResult
   ActOnClassPropertyRefExpr(IdentifierInfo &receiverName,
                             IdentifierInfo &propertyName,
                             SourceLocation receiverNameLoc,
                             SourceLocation propertyNameLoc);
 
   ObjCMethodDecl *tryCaptureObjCSelf(SourceLocation Loc);
 
   /// Describes the kind of message expression indicated by a message
   /// send that starts with an identifier.
   enum ObjCMessageKind {
     /// The message is sent to 'super'.
     ObjCSuperMessage,
     /// The message is an instance message.
     ObjCInstanceMessage,
     /// The message is a class message, and the identifier is a type
     /// name.
     ObjCClassMessage
   };
 
   ObjCMessageKind getObjCMessageKind(Scope *S,
                                      IdentifierInfo *Name,
                                      SourceLocation NameLoc,
                                      bool IsSuper,
                                      bool HasTrailingDot,
                                      ParsedType &ReceiverType);
 
   ExprResult ActOnSuperMessage(Scope *S, SourceLocation SuperLoc,
                                Selector Sel,
                                SourceLocation LBracLoc,
                                ArrayRef<SourceLocation> SelectorLocs,
                                SourceLocation RBracLoc,
                                MultiExprArg Args);
 
   ExprResult BuildClassMessage(TypeSourceInfo *ReceiverTypeInfo,
                                QualType ReceiverType,
                                SourceLocation SuperLoc,
                                Selector Sel,
                                ObjCMethodDecl *Method,
                                SourceLocation LBracLoc,
                                ArrayRef<SourceLocation> SelectorLocs,
                                SourceLocation RBracLoc,
                                MultiExprArg Args,
                                bool isImplicit = false);
 
   ExprResult BuildClassMessageImplicit(QualType ReceiverType,
                                        bool isSuperReceiver,
                                        SourceLocation Loc,
                                        Selector Sel,
                                        ObjCMethodDecl *Method,
                                        MultiExprArg Args);
 
   ExprResult ActOnClassMessage(Scope *S,
                                ParsedType Receiver,
                                Selector Sel,
                                SourceLocation LBracLoc,
                                ArrayRef<SourceLocation> SelectorLocs,
                                SourceLocation RBracLoc,
                                MultiExprArg Args);
 
   ExprResult BuildInstanceMessage(Expr *Receiver,
                                   QualType ReceiverType,
                                   SourceLocation SuperLoc,
                                   Selector Sel,
                                   ObjCMethodDecl *Method,
                                   SourceLocation LBracLoc,
                                   ArrayRef<SourceLocation> SelectorLocs,
                                   SourceLocation RBracLoc,
                                   MultiExprArg Args,
                                   bool isImplicit = false);
 
   ExprResult BuildInstanceMessageImplicit(Expr *Receiver,
                                           QualType ReceiverType,
                                           SourceLocation Loc,
                                           Selector Sel,
                                           ObjCMethodDecl *Method,
                                           MultiExprArg Args);
 
   ExprResult ActOnInstanceMessage(Scope *S,
                                   Expr *Receiver,
                                   Selector Sel,
                                   SourceLocation LBracLoc,
                                   ArrayRef<SourceLocation> SelectorLocs,
                                   SourceLocation RBracLoc,
                                   MultiExprArg Args);
 
   ExprResult BuildObjCBridgedCast(SourceLocation LParenLoc,
                                   ObjCBridgeCastKind Kind,
                                   SourceLocation BridgeKeywordLoc,
                                   TypeSourceInfo *TSInfo,
                                   Expr *SubExpr);
 
   ExprResult ActOnObjCBridgedCast(Scope *S,
                                   SourceLocation LParenLoc,
                                   ObjCBridgeCastKind Kind,
                                   SourceLocation BridgeKeywordLoc,
                                   ParsedType Type,
                                   SourceLocation RParenLoc,
                                   Expr *SubExpr);
 
   void CheckTollFreeBridgeCast(QualType castType, Expr *castExpr);
 
   void CheckObjCBridgeRelatedCast(QualType castType, Expr *castExpr);
 
   bool CheckTollFreeBridgeStaticCast(QualType castType, Expr *castExpr,
                                      CastKind &Kind);
 
   bool checkObjCBridgeRelatedComponents(SourceLocation Loc,
                                         QualType DestType, QualType SrcType,
                                         ObjCInterfaceDecl *&RelatedClass,
                                         ObjCMethodDecl *&ClassMethod,
                                         ObjCMethodDecl *&InstanceMethod,
                                         TypedefNameDecl *&TDNDecl,
                                         bool CfToNs, bool Diagnose = true);
 
   bool CheckObjCBridgeRelatedConversions(SourceLocation Loc,
                                          QualType DestType, QualType SrcType,
                                          Expr *&SrcExpr, bool Diagnose = true);
 
   bool ConversionToObjCStringLiteralCheck(QualType DstType, Expr *&SrcExpr,
                                           bool Diagnose = true);
 
   bool checkInitMethod(ObjCMethodDecl *method, QualType receiverTypeIfCall);
 
   /// Check whether the given new method is a valid override of the
   /// given overridden method, and set any properties that should be inherited.
   void CheckObjCMethodOverride(ObjCMethodDecl *NewMethod,
                                const ObjCMethodDecl *Overridden);
 
   /// Describes the compatibility of a result type with its method.
   enum ResultTypeCompatibilityKind {
     RTC_Compatible,
     RTC_Incompatible,
     RTC_Unknown
   };
 
   void CheckObjCMethodDirectOverrides(ObjCMethodDecl *method,
                                       ObjCMethodDecl *overridden);
 
   void CheckObjCMethodOverrides(ObjCMethodDecl *ObjCMethod,
                                 ObjCInterfaceDecl *CurrentClass,
                                 ResultTypeCompatibilityKind RTC);
 
   enum PragmaOptionsAlignKind {
     POAK_Native,  // #pragma options align=native
     POAK_Natural, // #pragma options align=natural
     POAK_Packed,  // #pragma options align=packed
     POAK_Power,   // #pragma options align=power
     POAK_Mac68k,  // #pragma options align=mac68k
     POAK_Reset    // #pragma options align=reset
   };
 
   /// ActOnPragmaClangSection - Called on well formed \#pragma clang section
   void ActOnPragmaClangSection(SourceLocation PragmaLoc,
                                PragmaClangSectionAction Action,
                                PragmaClangSectionKind SecKind, StringRef SecName);
 
   /// ActOnPragmaOptionsAlign - Called on well formed \#pragma options align.
   void ActOnPragmaOptionsAlign(PragmaOptionsAlignKind Kind,
                                SourceLocation PragmaLoc);
 
   /// ActOnPragmaPack - Called on well formed \#pragma pack(...).
   void ActOnPragmaPack(SourceLocation PragmaLoc, PragmaMsStackAction Action,
                        StringRef SlotLabel, Expr *Alignment);
 
   enum class PragmaPackDiagnoseKind {
     NonDefaultStateAtInclude,
     ChangedStateAtExit
   };
 
   void DiagnoseNonDefaultPragmaPack(PragmaPackDiagnoseKind Kind,
                                     SourceLocation IncludeLoc);
   void DiagnoseUnterminatedPragmaPack();
 
   /// ActOnPragmaMSStruct - Called on well formed \#pragma ms_struct [on|off].
   void ActOnPragmaMSStruct(PragmaMSStructKind Kind);
 
   /// ActOnPragmaMSComment - Called on well formed
   /// \#pragma comment(kind, "arg").
   void ActOnPragmaMSComment(SourceLocation CommentLoc, PragmaMSCommentKind Kind,
                             StringRef Arg);
 
   /// ActOnPragmaMSPointersToMembers - called on well formed \#pragma
   /// pointers_to_members(representation method[, general purpose
   /// representation]).
   void ActOnPragmaMSPointersToMembers(
       LangOptions::PragmaMSPointersToMembersKind Kind,
       SourceLocation PragmaLoc);
 
   /// Called on well formed \#pragma vtordisp().
   void ActOnPragmaMSVtorDisp(PragmaMsStackAction Action,
                              SourceLocation PragmaLoc,
                              MSVtorDispMode Value);
 
   enum PragmaSectionKind {
     PSK_DataSeg,
     PSK_BSSSeg,
     PSK_ConstSeg,
     PSK_CodeSeg,
   };
 
   bool UnifySection(StringRef SectionName,
                     int SectionFlags,
                     DeclaratorDecl *TheDecl);
   bool UnifySection(StringRef SectionName,
                     int SectionFlags,
                     SourceLocation PragmaSectionLocation);
 
   /// Called on well formed \#pragma bss_seg/data_seg/const_seg/code_seg.
   void ActOnPragmaMSSeg(SourceLocation PragmaLocation,
                         PragmaMsStackAction Action,
                         llvm::StringRef StackSlotLabel,
                         StringLiteral *SegmentName,
                         llvm::StringRef PragmaName);
 
   /// Called on well formed \#pragma section().
   void ActOnPragmaMSSection(SourceLocation PragmaLocation,
                             int SectionFlags, StringLiteral *SegmentName);
 
   /// Called on well-formed \#pragma init_seg().
   void ActOnPragmaMSInitSeg(SourceLocation PragmaLocation,
                             StringLiteral *SegmentName);
 
   /// Called on #pragma clang __debug dump II
   void ActOnPragmaDump(Scope *S, SourceLocation Loc, IdentifierInfo *II);
 
   /// ActOnPragmaDetectMismatch - Call on well-formed \#pragma detect_mismatch
   void ActOnPragmaDetectMismatch(SourceLocation Loc, StringRef Name,
                                  StringRef Value);
 
   /// ActOnPragmaUnused - Called on well-formed '\#pragma unused'.
   void ActOnPragmaUnused(const Token &Identifier,
                          Scope *curScope,
                          SourceLocation PragmaLoc);
 
   /// ActOnPragmaVisibility - Called on well formed \#pragma GCC visibility... .
   void ActOnPragmaVisibility(const IdentifierInfo* VisType,
                              SourceLocation PragmaLoc);
 
   NamedDecl *DeclClonePragmaWeak(NamedDecl *ND, IdentifierInfo *II,
                                  SourceLocation Loc);
   void DeclApplyPragmaWeak(Scope *S, NamedDecl *ND, WeakInfo &W);
 
   /// ActOnPragmaWeakID - Called on well formed \#pragma weak ident.
   void ActOnPragmaWeakID(IdentifierInfo* WeakName,
                          SourceLocation PragmaLoc,
                          SourceLocation WeakNameLoc);
 
   /// ActOnPragmaRedefineExtname - Called on well formed
   /// \#pragma redefine_extname oldname newname.
   void ActOnPragmaRedefineExtname(IdentifierInfo* WeakName,
                                   IdentifierInfo* AliasName,
                                   SourceLocation PragmaLoc,
                                   SourceLocation WeakNameLoc,
                                   SourceLocation AliasNameLoc);
 
   /// ActOnPragmaWeakAlias - Called on well formed \#pragma weak ident = ident.
   void ActOnPragmaWeakAlias(IdentifierInfo* WeakName,
                             IdentifierInfo* AliasName,
                             SourceLocation PragmaLoc,
                             SourceLocation WeakNameLoc,
                             SourceLocation AliasNameLoc);
 
   /// ActOnPragmaFPContract - Called on well formed
   /// \#pragma {STDC,OPENCL} FP_CONTRACT and
   /// \#pragma clang fp contract
   void ActOnPragmaFPContract(LangOptions::FPContractModeKind FPC);
 
   /// ActOnPragmaFenvAccess - Called on well formed
   /// \#pragma STDC FENV_ACCESS
   void ActOnPragmaFEnvAccess(LangOptions::FEnvAccessModeKind FPC);
 
   /// Called to set rounding mode for floating point operations.
   void setRoundingMode(LangOptions::FPRoundingModeKind);
 
   /// Called to set exception behavior for floating point operations.
   void setExceptionMode(LangOptions::FPExceptionModeKind);
 
   /// AddAlignmentAttributesForRecord - Adds any needed alignment attributes to
   /// a the record decl, to handle '\#pragma pack' and '\#pragma options align'.
   void AddAlignmentAttributesForRecord(RecordDecl *RD);
 
   /// AddMsStructLayoutForRecord - Adds ms_struct layout attribute to record.
   void AddMsStructLayoutForRecord(RecordDecl *RD);
 
   /// FreePackedContext - Deallocate and null out PackContext.
   void FreePackedContext();
 
   /// PushNamespaceVisibilityAttr - Note that we've entered a
   /// namespace with a visibility attribute.
   void PushNamespaceVisibilityAttr(const VisibilityAttr *Attr,
                                    SourceLocation Loc);
 
   /// AddPushedVisibilityAttribute - If '\#pragma GCC visibility' was used,
   /// add an appropriate visibility attribute.
   void AddPushedVisibilityAttribute(Decl *RD);
 
   /// PopPragmaVisibility - Pop the top element of the visibility stack; used
   /// for '\#pragma GCC visibility' and visibility attributes on namespaces.
   void PopPragmaVisibility(bool IsNamespaceEnd, SourceLocation EndLoc);
 
   /// FreeVisContext - Deallocate and null out VisContext.
   void FreeVisContext();
 
   /// AddCFAuditedAttribute - Check whether we're currently within
   /// '\#pragma clang arc_cf_code_audited' and, if so, consider adding
   /// the appropriate attribute.
   void AddCFAuditedAttribute(Decl *D);
 
   void ActOnPragmaAttributeAttribute(ParsedAttr &Attribute,
                                      SourceLocation PragmaLoc,
                                      attr::ParsedSubjectMatchRuleSet Rules);
   void ActOnPragmaAttributeEmptyPush(SourceLocation PragmaLoc,
                                      const IdentifierInfo *Namespace);
 
   /// Called on well-formed '\#pragma clang attribute pop'.
   void ActOnPragmaAttributePop(SourceLocation PragmaLoc,
                                const IdentifierInfo *Namespace);
 
   /// Adds the attributes that have been specified using the
   /// '\#pragma clang attribute push' directives to the given declaration.
   void AddPragmaAttributes(Scope *S, Decl *D);
 
   void DiagnoseUnterminatedPragmaAttribute();
 
   /// Called on well formed \#pragma clang optimize.
   void ActOnPragmaOptimize(bool On, SourceLocation PragmaLoc);
 
   /// Get the location for the currently active "\#pragma clang optimize
   /// off". If this location is invalid, then the state of the pragma is "on".
   SourceLocation getOptimizeOffPragmaLocation() const {
     return OptimizeOffPragmaLocation;
   }
 
   /// Only called on function definitions; if there is a pragma in scope
   /// with the effect of a range-based optnone, consider marking the function
   /// with attribute optnone.
   void AddRangeBasedOptnone(FunctionDecl *FD);
 
   /// Adds the 'optnone' attribute to the function declaration if there
   /// are no conflicts; Loc represents the location causing the 'optnone'
   /// attribute to be added (usually because of a pragma).
   void AddOptnoneAttributeIfNoConflicts(FunctionDecl *FD, SourceLocation Loc);
 
   /// AddAlignedAttr - Adds an aligned attribute to a particular declaration.
   void AddAlignedAttr(Decl *D, const AttributeCommonInfo &CI, Expr *E,
                       bool IsPackExpansion);
   void AddAlignedAttr(Decl *D, const AttributeCommonInfo &CI, TypeSourceInfo *T,
                       bool IsPackExpansion);
 
   /// AddAssumeAlignedAttr - Adds an assume_aligned attribute to a particular
   /// declaration.
   void AddAssumeAlignedAttr(Decl *D, const AttributeCommonInfo &CI, Expr *E,
                             Expr *OE);
 
   /// AddAllocAlignAttr - Adds an alloc_align attribute to a particular
   /// declaration.
   void AddAllocAlignAttr(Decl *D, const AttributeCommonInfo &CI,
                          Expr *ParamExpr);
 
   /// AddAlignValueAttr - Adds an align_value attribute to a particular
   /// declaration.
   void AddAlignValueAttr(Decl *D, const AttributeCommonInfo &CI, Expr *E);
 
   /// AddLaunchBoundsAttr - Adds a launch_bounds attribute to a particular
   /// declaration.
   void AddLaunchBoundsAttr(Decl *D, const AttributeCommonInfo &CI,
                            Expr *MaxThreads, Expr *MinBlocks);
 
   /// AddModeAttr - Adds a mode attribute to a particular declaration.
   void AddModeAttr(Decl *D, const AttributeCommonInfo &CI, IdentifierInfo *Name,
                    bool InInstantiation = false);
 
   void AddParameterABIAttr(Decl *D, const AttributeCommonInfo &CI,
                            ParameterABI ABI);
 
   enum class RetainOwnershipKind {NS, CF, OS};
   void AddXConsumedAttr(Decl *D, const AttributeCommonInfo &CI,
                         RetainOwnershipKind K, bool IsTemplateInstantiation);
 
   /// addAMDGPUFlatWorkGroupSizeAttr - Adds an amdgpu_flat_work_group_size
   /// attribute to a particular declaration.
   void addAMDGPUFlatWorkGroupSizeAttr(Decl *D, const AttributeCommonInfo &CI,
                                       Expr *Min, Expr *Max);
 
   /// addAMDGPUWavePersEUAttr - Adds an amdgpu_waves_per_eu attribute to a
   /// particular declaration.
   void addAMDGPUWavesPerEUAttr(Decl *D, const AttributeCommonInfo &CI,
                                Expr *Min, Expr *Max);
 
   bool checkNSReturnsRetainedReturnType(SourceLocation loc, QualType type);
 
   //===--------------------------------------------------------------------===//
   // C++ Coroutines TS
   //
   bool ActOnCoroutineBodyStart(Scope *S, SourceLocation KwLoc,
                                StringRef Keyword);
   ExprResult ActOnCoawaitExpr(Scope *S, SourceLocation KwLoc, Expr *E);
   ExprResult ActOnCoyieldExpr(Scope *S, SourceLocation KwLoc, Expr *E);
   StmtResult ActOnCoreturnStmt(Scope *S, SourceLocation KwLoc, Expr *E);
 
   ExprResult BuildResolvedCoawaitExpr(SourceLocation KwLoc, Expr *E,
                                       bool IsImplicit = false);
   ExprResult BuildUnresolvedCoawaitExpr(SourceLocation KwLoc, Expr *E,
                                         UnresolvedLookupExpr* Lookup);
   ExprResult BuildCoyieldExpr(SourceLocation KwLoc, Expr *E);
   StmtResult BuildCoreturnStmt(SourceLocation KwLoc, Expr *E,
                                bool IsImplicit = false);
   StmtResult BuildCoroutineBodyStmt(CoroutineBodyStmt::CtorArgs);
   bool buildCoroutineParameterMoves(SourceLocation Loc);
   VarDecl *buildCoroutinePromise(SourceLocation Loc);
   void CheckCompletedCoroutineBody(FunctionDecl *FD, Stmt *&Body);
   ClassTemplateDecl *lookupCoroutineTraits(SourceLocation KwLoc,
                                            SourceLocation FuncLoc);
 
   //===--------------------------------------------------------------------===//
   // OpenCL extensions.
   //
 private:
   std::string CurrOpenCLExtension;
   /// Extensions required by an OpenCL type.
   llvm::DenseMap<const Type*, std::set<std::string>> OpenCLTypeExtMap;
   /// Extensions required by an OpenCL declaration.
   llvm::DenseMap<const Decl*, std::set<std::string>> OpenCLDeclExtMap;
 public:
   llvm::StringRef getCurrentOpenCLExtension() const {
     return CurrOpenCLExtension;
   }
 
   /// Check if a function declaration \p FD associates with any
   /// extensions present in OpenCLDeclExtMap and if so return the
   /// extension(s) name(s).
   std::string getOpenCLExtensionsFromDeclExtMap(FunctionDecl *FD);
 
   /// Check if a function type \p FT associates with any
   /// extensions present in OpenCLTypeExtMap and if so return the
   /// extension(s) name(s).
   std::string getOpenCLExtensionsFromTypeExtMap(FunctionType *FT);
 
   /// Find an extension in an appropriate extension map and return its name
   template<typename T, typename MapT>
   std::string getOpenCLExtensionsFromExtMap(T* FT, MapT &Map);
 
   void setCurrentOpenCLExtension(llvm::StringRef Ext) {
     CurrOpenCLExtension = std::string(Ext);
   }
 
   /// Set OpenCL extensions for a type which can only be used when these
   /// OpenCL extensions are enabled. If \p Exts is empty, do nothing.
   /// \param Exts A space separated list of OpenCL extensions.
   void setOpenCLExtensionForType(QualType T, llvm::StringRef Exts);
 
   /// Set OpenCL extensions for a declaration which can only be
   /// used when these OpenCL extensions are enabled. If \p Exts is empty, do
   /// nothing.
   /// \param Exts A space separated list of OpenCL extensions.
   void setOpenCLExtensionForDecl(Decl *FD, llvm::StringRef Exts);
 
   /// Set current OpenCL extensions for a type which can only be used
   /// when these OpenCL extensions are enabled. If current OpenCL extension is
   /// empty, do nothing.
   void setCurrentOpenCLExtensionForType(QualType T);
 
   /// Set current OpenCL extensions for a declaration which
   /// can only be used when these OpenCL extensions are enabled. If current
   /// OpenCL extension is empty, do nothing.
   void setCurrentOpenCLExtensionForDecl(Decl *FD);
 
   bool isOpenCLDisabledDecl(Decl *FD);
 
   /// Check if type \p T corresponding to declaration specifier \p DS
   /// is disabled due to required OpenCL extensions being disabled. If so,
   /// emit diagnostics.
   /// \return true if type is disabled.
   bool checkOpenCLDisabledTypeDeclSpec(const DeclSpec &DS, QualType T);
 
   /// Check if declaration \p D used by expression \p E
   /// is disabled due to required OpenCL extensions being disabled. If so,
   /// emit diagnostics.
   /// \return true if type is disabled.
   bool checkOpenCLDisabledDecl(const NamedDecl &D, const Expr &E);
 
   //===--------------------------------------------------------------------===//
   // OpenMP directives and clauses.
   //
 private:
   void *VarDataSharingAttributesStack;
   /// Number of nested '#pragma omp declare target' directives.
   unsigned DeclareTargetNestingLevel = 0;
   /// Initialization of data-sharing attributes stack.
   void InitDataSharingAttributesStack();
   void DestroyDataSharingAttributesStack();
   ExprResult
   VerifyPositiveIntegerConstantInClause(Expr *Op, OpenMPClauseKind CKind,
                                         bool StrictlyPositive = true);
   /// Returns OpenMP nesting level for current directive.
   unsigned getOpenMPNestingLevel() const;
 
   /// Adjusts the function scopes index for the target-based regions.
   void adjustOpenMPTargetScopeIndex(unsigned &FunctionScopesIndex,
                                     unsigned Level) const;
 
   /// Returns the number of scopes associated with the construct on the given
   /// OpenMP level.
   int getNumberOfConstructScopes(unsigned Level) const;
 
   /// Push new OpenMP function region for non-capturing function.
   void pushOpenMPFunctionRegion();
 
   /// Pop OpenMP function region for non-capturing function.
   void popOpenMPFunctionRegion(const sema::FunctionScopeInfo *OldFSI);
 
   /// Check whether we're allowed to call Callee from the current function.
   void checkOpenMPDeviceFunction(SourceLocation Loc, FunctionDecl *Callee,
                                  bool CheckForDelayedContext = true);
 
   /// Check whether we're allowed to call Callee from the current function.
   void checkOpenMPHostFunction(SourceLocation Loc, FunctionDecl *Callee,
                                bool CheckCaller = true);
 
   /// Check if the expression is allowed to be used in expressions for the
   /// OpenMP devices.
   void checkOpenMPDeviceExpr(const Expr *E);
 
   /// Finishes analysis of the deferred functions calls that may be declared as
   /// host/nohost during device/host compilation.
   void finalizeOpenMPDelayedAnalysis();
 
   /// Checks if a type or a declaration is disabled due to the owning extension
   /// being disabled, and emits diagnostic messages if it is disabled.
   /// \param D type or declaration to be checked.
   /// \param DiagLoc source location for the diagnostic message.
   /// \param DiagInfo information to be emitted for the diagnostic message.
   /// \param SrcRange source range of the declaration.
   /// \param Map maps type or declaration to the extensions.
   /// \param Selector selects diagnostic message: 0 for type and 1 for
   ///        declaration.
   /// \return true if the type or declaration is disabled.
   template <typename T, typename DiagLocT, typename DiagInfoT, typename MapT>
   bool checkOpenCLDisabledTypeOrDecl(T D, DiagLocT DiagLoc, DiagInfoT DiagInfo,
                                      MapT &Map, unsigned Selector = 0,
                                      SourceRange SrcRange = SourceRange());
 
   /// Marks all the functions that might be required for the currently active
   /// OpenMP context.
   void markOpenMPDeclareVariantFuncsReferenced(SourceLocation Loc,
                                                FunctionDecl *Func,
                                                bool MightBeOdrUse);
 
 public:
   /// Struct to store the context selectors info for declare variant directive.
 
   /// Checks if the variant/multiversion functions are compatible.
   bool areMultiversionVariantFunctionsCompatible(
       const FunctionDecl *OldFD, const FunctionDecl *NewFD,
       const PartialDiagnostic &NoProtoDiagID,
       const PartialDiagnosticAt &NoteCausedDiagIDAt,
       const PartialDiagnosticAt &NoSupportDiagIDAt,
       const PartialDiagnosticAt &DiffDiagIDAt, bool TemplatesSupported,
       bool ConstexprSupported, bool CLinkageMayDiffer);
 
   /// Function tries to capture lambda's captured variables in the OpenMP region
   /// before the original lambda is captured.
   void tryCaptureOpenMPLambdas(ValueDecl *V);
 
   /// Return true if the provided declaration \a VD should be captured by
   /// reference.
   /// \param Level Relative level of nested OpenMP construct for that the check
   /// is performed.
   /// \param OpenMPCaptureLevel Capture level within an OpenMP construct.
   bool isOpenMPCapturedByRef(const ValueDecl *D, unsigned Level,
                              unsigned OpenMPCaptureLevel) const;
 
   /// Check if the specified variable is used in one of the private
   /// clauses (private, firstprivate, lastprivate, reduction etc.) in OpenMP
   /// constructs.
   VarDecl *isOpenMPCapturedDecl(ValueDecl *D, bool CheckScopeInfo = false,
                                 unsigned StopAt = 0);
   ExprResult getOpenMPCapturedExpr(VarDecl *Capture, ExprValueKind VK,
                                    ExprObjectKind OK, SourceLocation Loc);
 
   /// If the current region is a loop-based region, mark the start of the loop
   /// construct.
   void startOpenMPLoop();
 
   /// If the current region is a range loop-based region, mark the start of the
   /// loop construct.
   void startOpenMPCXXRangeFor();
 
   /// Check if the specified variable is used in 'private' clause.
   /// \param Level Relative level of nested OpenMP construct for that the check
   /// is performed.
   OpenMPClauseKind isOpenMPPrivateDecl(ValueDecl *D, unsigned Level,
                                        unsigned CapLevel) const;
 
   /// Sets OpenMP capture kind (OMPC_private, OMPC_firstprivate, OMPC_map etc.)
   /// for \p FD based on DSA for the provided corresponding captured declaration
   /// \p D.
   void setOpenMPCaptureKind(FieldDecl *FD, const ValueDecl *D, unsigned Level);
 
   /// Check if the specified variable is captured  by 'target' directive.
   /// \param Level Relative level of nested OpenMP construct for that the check
   /// is performed.
   bool isOpenMPTargetCapturedDecl(const ValueDecl *D, unsigned Level,
                                   unsigned CaptureLevel) const;
 
   /// Check if the specified global variable must be captured  by outer capture
   /// regions.
   /// \param Level Relative level of nested OpenMP construct for that
   /// the check is performed.
   bool isOpenMPGlobalCapturedDecl(ValueDecl *D, unsigned Level,
                                   unsigned CaptureLevel) const;
 
   ExprResult PerformOpenMPImplicitIntegerConversion(SourceLocation OpLoc,
                                                     Expr *Op);
   /// Called on start of new data sharing attribute block.
   void StartOpenMPDSABlock(OpenMPDirectiveKind K,
                            const DeclarationNameInfo &DirName, Scope *CurScope,
                            SourceLocation Loc);
   /// Start analysis of clauses.
   void StartOpenMPClause(OpenMPClauseKind K);
   /// End analysis of clauses.
   void EndOpenMPClause();
   /// Called on end of data sharing attribute block.
   void EndOpenMPDSABlock(Stmt *CurDirective);
 
   /// Check if the current region is an OpenMP loop region and if it is,
   /// mark loop control variable, used in \p Init for loop initialization, as
   /// private by default.
   /// \param Init First part of the for loop.
   void ActOnOpenMPLoopInitialization(SourceLocation ForLoc, Stmt *Init);
 
   // OpenMP directives and clauses.
   /// Called on correct id-expression from the '#pragma omp
   /// threadprivate'.
   ExprResult ActOnOpenMPIdExpression(Scope *CurScope, CXXScopeSpec &ScopeSpec,
                                      const DeclarationNameInfo &Id,
                                      OpenMPDirectiveKind Kind);
   /// Called on well-formed '#pragma omp threadprivate'.
   DeclGroupPtrTy ActOnOpenMPThreadprivateDirective(
                                      SourceLocation Loc,
                                      ArrayRef<Expr *> VarList);
   /// Builds a new OpenMPThreadPrivateDecl and checks its correctness.
   OMPThreadPrivateDecl *CheckOMPThreadPrivateDecl(SourceLocation Loc,
                                                   ArrayRef<Expr *> VarList);
   /// Called on well-formed '#pragma omp allocate'.
   DeclGroupPtrTy ActOnOpenMPAllocateDirective(SourceLocation Loc,
                                               ArrayRef<Expr *> VarList,
                                               ArrayRef<OMPClause *> Clauses,
                                               DeclContext *Owner = nullptr);
   /// Called on well-formed '#pragma omp requires'.
   DeclGroupPtrTy ActOnOpenMPRequiresDirective(SourceLocation Loc,
                                               ArrayRef<OMPClause *> ClauseList);
   /// Check restrictions on Requires directive
   OMPRequiresDecl *CheckOMPRequiresDecl(SourceLocation Loc,
                                         ArrayRef<OMPClause *> Clauses);
   /// Check if the specified type is allowed to be used in 'omp declare
   /// reduction' construct.
   QualType ActOnOpenMPDeclareReductionType(SourceLocation TyLoc,
                                            TypeResult ParsedType);
   /// Called on start of '#pragma omp declare reduction'.
   DeclGroupPtrTy ActOnOpenMPDeclareReductionDirectiveStart(
       Scope *S, DeclContext *DC, DeclarationName Name,
       ArrayRef<std::pair<QualType, SourceLocation>> ReductionTypes,
       AccessSpecifier AS, Decl *PrevDeclInScope = nullptr);
   /// Initialize declare reduction construct initializer.
   void ActOnOpenMPDeclareReductionCombinerStart(Scope *S, Decl *D);
   /// Finish current declare reduction construct initializer.
   void ActOnOpenMPDeclareReductionCombinerEnd(Decl *D, Expr *Combiner);
   /// Initialize declare reduction construct initializer.
   /// \return omp_priv variable.
   VarDecl *ActOnOpenMPDeclareReductionInitializerStart(Scope *S, Decl *D);
   /// Finish current declare reduction construct initializer.
   void ActOnOpenMPDeclareReductionInitializerEnd(Decl *D, Expr *Initializer,
                                                  VarDecl *OmpPrivParm);
   /// Called at the end of '#pragma omp declare reduction'.
   DeclGroupPtrTy ActOnOpenMPDeclareReductionDirectiveEnd(
       Scope *S, DeclGroupPtrTy DeclReductions, bool IsValid);
 
   /// Check variable declaration in 'omp declare mapper' construct.
   TypeResult ActOnOpenMPDeclareMapperVarDecl(Scope *S, Declarator &D);
   /// Check if the specified type is allowed to be used in 'omp declare
   /// mapper' construct.
   QualType ActOnOpenMPDeclareMapperType(SourceLocation TyLoc,
                                         TypeResult ParsedType);
   /// Called on start of '#pragma omp declare mapper'.
   OMPDeclareMapperDecl *ActOnOpenMPDeclareMapperDirectiveStart(
       Scope *S, DeclContext *DC, DeclarationName Name, QualType MapperType,
       SourceLocation StartLoc, DeclarationName VN, AccessSpecifier AS,
       Decl *PrevDeclInScope = nullptr);
   /// Build the mapper variable of '#pragma omp declare mapper'.
   void ActOnOpenMPDeclareMapperDirectiveVarDecl(OMPDeclareMapperDecl *DMD,
                                                 Scope *S, QualType MapperType,
                                                 SourceLocation StartLoc,
                                                 DeclarationName VN);
   /// Called at the end of '#pragma omp declare mapper'.
   DeclGroupPtrTy
   ActOnOpenMPDeclareMapperDirectiveEnd(OMPDeclareMapperDecl *D, Scope *S,
                                        ArrayRef<OMPClause *> ClauseList);
 
   /// Called on the start of target region i.e. '#pragma omp declare target'.
   bool ActOnStartOpenMPDeclareTargetDirective(SourceLocation Loc);
   /// Called at the end of target region i.e. '#pragme omp end declare target'.
   void ActOnFinishOpenMPDeclareTargetDirective();
   /// Searches for the provided declaration name for OpenMP declare target
   /// directive.
   NamedDecl *
   lookupOpenMPDeclareTargetName(Scope *CurScope, CXXScopeSpec &ScopeSpec,
                                 const DeclarationNameInfo &Id,
                                 NamedDeclSetType &SameDirectiveDecls);
   /// Called on correct id-expression from the '#pragma omp declare target'.
   void ActOnOpenMPDeclareTargetName(NamedDecl *ND, SourceLocation Loc,
                                     OMPDeclareTargetDeclAttr::MapTypeTy MT,
                                     OMPDeclareTargetDeclAttr::DevTypeTy DT);
   /// Check declaration inside target region.
   void
   checkDeclIsAllowedInOpenMPTarget(Expr *E, Decl *D,
                                    SourceLocation IdLoc = SourceLocation());
   /// Return true inside OpenMP declare target region.
   bool isInOpenMPDeclareTargetContext() const {
     return DeclareTargetNestingLevel > 0;
   }
   /// Return true inside OpenMP target region.
   bool isInOpenMPTargetExecutionDirective() const;
 
   /// Return the number of captured regions created for an OpenMP directive.
   static int getOpenMPCaptureLevels(OpenMPDirectiveKind Kind);
 
   /// Initialization of captured region for OpenMP region.
   void ActOnOpenMPRegionStart(OpenMPDirectiveKind DKind, Scope *CurScope);
   /// End of OpenMP region.
   ///
   /// \param S Statement associated with the current OpenMP region.
   /// \param Clauses List of clauses for the current OpenMP region.
   ///
   /// \returns Statement for finished OpenMP region.
   StmtResult ActOnOpenMPRegionEnd(StmtResult S, ArrayRef<OMPClause *> Clauses);
   StmtResult ActOnOpenMPExecutableDirective(
       OpenMPDirectiveKind Kind, const DeclarationNameInfo &DirName,
       OpenMPDirectiveKind CancelRegion, ArrayRef<OMPClause *> Clauses,
       Stmt *AStmt, SourceLocation StartLoc, SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp parallel' after parsing
   /// of the  associated statement.
   StmtResult ActOnOpenMPParallelDirective(ArrayRef<OMPClause *> Clauses,
                                           Stmt *AStmt,
                                           SourceLocation StartLoc,
                                           SourceLocation EndLoc);
   using VarsWithInheritedDSAType =
       llvm::SmallDenseMap<const ValueDecl *, const Expr *, 4>;
   /// Called on well-formed '\#pragma omp simd' after parsing
   /// of the associated statement.
   StmtResult
   ActOnOpenMPSimdDirective(ArrayRef<OMPClause *> Clauses, Stmt *AStmt,
                            SourceLocation StartLoc, SourceLocation EndLoc,
                            VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp for' after parsing
   /// of the associated statement.
   StmtResult
   ActOnOpenMPForDirective(ArrayRef<OMPClause *> Clauses, Stmt *AStmt,
                           SourceLocation StartLoc, SourceLocation EndLoc,
                           VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp for simd' after parsing
   /// of the associated statement.
   StmtResult
   ActOnOpenMPForSimdDirective(ArrayRef<OMPClause *> Clauses, Stmt *AStmt,
                               SourceLocation StartLoc, SourceLocation EndLoc,
                               VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp sections' after parsing
   /// of the associated statement.
   StmtResult ActOnOpenMPSectionsDirective(ArrayRef<OMPClause *> Clauses,
                                           Stmt *AStmt, SourceLocation StartLoc,
                                           SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp section' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPSectionDirective(Stmt *AStmt, SourceLocation StartLoc,
                                          SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp single' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPSingleDirective(ArrayRef<OMPClause *> Clauses,
                                         Stmt *AStmt, SourceLocation StartLoc,
                                         SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp master' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPMasterDirective(Stmt *AStmt, SourceLocation StartLoc,
                                         SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp critical' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPCriticalDirective(const DeclarationNameInfo &DirName,
                                           ArrayRef<OMPClause *> Clauses,
                                           Stmt *AStmt, SourceLocation StartLoc,
                                           SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp parallel for' after parsing
   /// of the  associated statement.
   StmtResult ActOnOpenMPParallelForDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp parallel for simd' after
   /// parsing of the  associated statement.
   StmtResult ActOnOpenMPParallelForSimdDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp parallel master' after
   /// parsing of the  associated statement.
   StmtResult ActOnOpenMPParallelMasterDirective(ArrayRef<OMPClause *> Clauses,
                                                 Stmt *AStmt,
                                                 SourceLocation StartLoc,
                                                 SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp parallel sections' after
   /// parsing of the  associated statement.
   StmtResult ActOnOpenMPParallelSectionsDirective(ArrayRef<OMPClause *> Clauses,
                                                   Stmt *AStmt,
                                                   SourceLocation StartLoc,
                                                   SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp task' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPTaskDirective(ArrayRef<OMPClause *> Clauses,
                                       Stmt *AStmt, SourceLocation StartLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp taskyield'.
   StmtResult ActOnOpenMPTaskyieldDirective(SourceLocation StartLoc,
                                            SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp barrier'.
   StmtResult ActOnOpenMPBarrierDirective(SourceLocation StartLoc,
                                          SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp taskwait'.
   StmtResult ActOnOpenMPTaskwaitDirective(SourceLocation StartLoc,
                                           SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp taskgroup'.
   StmtResult ActOnOpenMPTaskgroupDirective(ArrayRef<OMPClause *> Clauses,
                                            Stmt *AStmt, SourceLocation StartLoc,
                                            SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp flush'.
   StmtResult ActOnOpenMPFlushDirective(ArrayRef<OMPClause *> Clauses,
                                        SourceLocation StartLoc,
                                        SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp depobj'.
   StmtResult ActOnOpenMPDepobjDirective(ArrayRef<OMPClause *> Clauses,
                                         SourceLocation StartLoc,
                                         SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp ordered' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPOrderedDirective(ArrayRef<OMPClause *> Clauses,
                                          Stmt *AStmt, SourceLocation StartLoc,
                                          SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp atomic' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPAtomicDirective(ArrayRef<OMPClause *> Clauses,
                                         Stmt *AStmt, SourceLocation StartLoc,
                                         SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp target' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPTargetDirective(ArrayRef<OMPClause *> Clauses,
                                         Stmt *AStmt, SourceLocation StartLoc,
                                         SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp target data' after parsing of
   /// the associated statement.
   StmtResult ActOnOpenMPTargetDataDirective(ArrayRef<OMPClause *> Clauses,
                                             Stmt *AStmt, SourceLocation StartLoc,
                                             SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp target enter data' after
   /// parsing of the associated statement.
   StmtResult ActOnOpenMPTargetEnterDataDirective(ArrayRef<OMPClause *> Clauses,
                                                  SourceLocation StartLoc,
                                                  SourceLocation EndLoc,
                                                  Stmt *AStmt);
   /// Called on well-formed '\#pragma omp target exit data' after
   /// parsing of the associated statement.
   StmtResult ActOnOpenMPTargetExitDataDirective(ArrayRef<OMPClause *> Clauses,
                                                 SourceLocation StartLoc,
                                                 SourceLocation EndLoc,
                                                 Stmt *AStmt);
   /// Called on well-formed '\#pragma omp target parallel' after
   /// parsing of the associated statement.
   StmtResult ActOnOpenMPTargetParallelDirective(ArrayRef<OMPClause *> Clauses,
                                                 Stmt *AStmt,
                                                 SourceLocation StartLoc,
                                                 SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp target parallel for' after
   /// parsing of the  associated statement.
   StmtResult ActOnOpenMPTargetParallelForDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp teams' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPTeamsDirective(ArrayRef<OMPClause *> Clauses,
                                        Stmt *AStmt, SourceLocation StartLoc,
                                        SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp cancellation point'.
   StmtResult
   ActOnOpenMPCancellationPointDirective(SourceLocation StartLoc,
                                         SourceLocation EndLoc,
                                         OpenMPDirectiveKind CancelRegion);
   /// Called on well-formed '\#pragma omp cancel'.
   StmtResult ActOnOpenMPCancelDirective(ArrayRef<OMPClause *> Clauses,
                                         SourceLocation StartLoc,
                                         SourceLocation EndLoc,
                                         OpenMPDirectiveKind CancelRegion);
   /// Called on well-formed '\#pragma omp taskloop' after parsing of the
   /// associated statement.
   StmtResult
   ActOnOpenMPTaskLoopDirective(ArrayRef<OMPClause *> Clauses, Stmt *AStmt,
                                SourceLocation StartLoc, SourceLocation EndLoc,
                                VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp taskloop simd' after parsing of
   /// the associated statement.
   StmtResult ActOnOpenMPTaskLoopSimdDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp master taskloop' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPMasterTaskLoopDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp master taskloop simd' after parsing of
   /// the associated statement.
   StmtResult ActOnOpenMPMasterTaskLoopSimdDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp parallel master taskloop' after
   /// parsing of the associated statement.
   StmtResult ActOnOpenMPParallelMasterTaskLoopDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp parallel master taskloop simd' after
   /// parsing of the associated statement.
   StmtResult ActOnOpenMPParallelMasterTaskLoopSimdDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp distribute' after parsing
   /// of the associated statement.
   StmtResult
   ActOnOpenMPDistributeDirective(ArrayRef<OMPClause *> Clauses, Stmt *AStmt,
                                  SourceLocation StartLoc, SourceLocation EndLoc,
                                  VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp target update'.
   StmtResult ActOnOpenMPTargetUpdateDirective(ArrayRef<OMPClause *> Clauses,
                                               SourceLocation StartLoc,
                                               SourceLocation EndLoc,
                                               Stmt *AStmt);
   /// Called on well-formed '\#pragma omp distribute parallel for' after
   /// parsing of the associated statement.
   StmtResult ActOnOpenMPDistributeParallelForDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp distribute parallel for simd'
   /// after parsing of the associated statement.
   StmtResult ActOnOpenMPDistributeParallelForSimdDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp distribute simd' after
   /// parsing of the associated statement.
   StmtResult ActOnOpenMPDistributeSimdDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp target parallel for simd' after
   /// parsing of the associated statement.
   StmtResult ActOnOpenMPTargetParallelForSimdDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp target simd' after parsing of
   /// the associated statement.
   StmtResult
   ActOnOpenMPTargetSimdDirective(ArrayRef<OMPClause *> Clauses, Stmt *AStmt,
                                  SourceLocation StartLoc, SourceLocation EndLoc,
                                  VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp teams distribute' after parsing of
   /// the associated statement.
   StmtResult ActOnOpenMPTeamsDistributeDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp teams distribute simd' after parsing
   /// of the associated statement.
   StmtResult ActOnOpenMPTeamsDistributeSimdDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp teams distribute parallel for simd'
   /// after parsing of the associated statement.
   StmtResult ActOnOpenMPTeamsDistributeParallelForSimdDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp teams distribute parallel for'
   /// after parsing of the associated statement.
   StmtResult ActOnOpenMPTeamsDistributeParallelForDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp target teams' after parsing of the
   /// associated statement.
   StmtResult ActOnOpenMPTargetTeamsDirective(ArrayRef<OMPClause *> Clauses,
                                              Stmt *AStmt,
                                              SourceLocation StartLoc,
                                              SourceLocation EndLoc);
   /// Called on well-formed '\#pragma omp target teams distribute' after parsing
   /// of the associated statement.
   StmtResult ActOnOpenMPTargetTeamsDistributeDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp target teams distribute parallel for'
   /// after parsing of the associated statement.
   StmtResult ActOnOpenMPTargetTeamsDistributeParallelForDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp target teams distribute parallel for
   /// simd' after parsing of the associated statement.
   StmtResult ActOnOpenMPTargetTeamsDistributeParallelForSimdDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
   /// Called on well-formed '\#pragma omp target teams distribute simd' after
   /// parsing of the associated statement.
   StmtResult ActOnOpenMPTargetTeamsDistributeSimdDirective(
       ArrayRef<OMPClause *> Clauses, Stmt *AStmt, SourceLocation StartLoc,
       SourceLocation EndLoc, VarsWithInheritedDSAType &VarsWithImplicitDSA);
 
   /// Checks correctness of linear modifiers.
   bool CheckOpenMPLinearModifier(OpenMPLinearClauseKind LinKind,
                                  SourceLocation LinLoc);
   /// Checks that the specified declaration matches requirements for the linear
   /// decls.
   bool CheckOpenMPLinearDecl(const ValueDecl *D, SourceLocation ELoc,
                              OpenMPLinearClauseKind LinKind, QualType Type,
                              bool IsDeclareSimd = false);
 
   /// Called on well-formed '\#pragma omp declare simd' after parsing of
   /// the associated method/function.
   DeclGroupPtrTy ActOnOpenMPDeclareSimdDirective(
       DeclGroupPtrTy DG, OMPDeclareSimdDeclAttr::BranchStateTy BS,
       Expr *Simdlen, ArrayRef<Expr *> Uniforms, ArrayRef<Expr *> Aligneds,
       ArrayRef<Expr *> Alignments, ArrayRef<Expr *> Linears,
       ArrayRef<unsigned> LinModifiers, ArrayRef<Expr *> Steps, SourceRange SR);
 
   /// Checks '\#pragma omp declare variant' variant function and original
   /// functions after parsing of the associated method/function.
   /// \param DG Function declaration to which declare variant directive is
   /// applied to.
   /// \param VariantRef Expression that references the variant function, which
   /// must be used instead of the original one, specified in \p DG.
   /// \param TI The trait info object representing the match clause.
   /// \returns None, if the function/variant function are not compatible with
   /// the pragma, pair of original function/variant ref expression otherwise.
   Optional<std::pair<FunctionDecl *, Expr *>>
   checkOpenMPDeclareVariantFunction(DeclGroupPtrTy DG, Expr *VariantRef,
                                     OMPTraitInfo &TI, SourceRange SR);
 
   /// Called on well-formed '\#pragma omp declare variant' after parsing of
   /// the associated method/function.
   /// \param FD Function declaration to which declare variant directive is
   /// applied to.
   /// \param VariantRef Expression that references the variant function, which
   /// must be used instead of the original one, specified in \p DG.
   /// \param TI The context traits associated with the function variant.
   void ActOnOpenMPDeclareVariantDirective(FunctionDecl *FD, Expr *VariantRef,
                                           OMPTraitInfo &TI, SourceRange SR);
 
   OMPClause *ActOnOpenMPSingleExprClause(OpenMPClauseKind Kind,
                                          Expr *Expr,
                                          SourceLocation StartLoc,
                                          SourceLocation LParenLoc,
                                          SourceLocation EndLoc);
   /// Called on well-formed 'allocator' clause.
   OMPClause *ActOnOpenMPAllocatorClause(Expr *Allocator,
                                         SourceLocation StartLoc,
                                         SourceLocation LParenLoc,
                                         SourceLocation EndLoc);
   /// Called on well-formed 'if' clause.
   OMPClause *ActOnOpenMPIfClause(OpenMPDirectiveKind NameModifier,
                                  Expr *Condition, SourceLocation StartLoc,
                                  SourceLocation LParenLoc,
                                  SourceLocation NameModifierLoc,
                                  SourceLocation ColonLoc,
                                  SourceLocation EndLoc);
   /// Called on well-formed 'final' clause.
   OMPClause *ActOnOpenMPFinalClause(Expr *Condition, SourceLocation StartLoc,
                                     SourceLocation LParenLoc,
                                     SourceLocation EndLoc);
   /// Called on well-formed 'num_threads' clause.
   OMPClause *ActOnOpenMPNumThreadsClause(Expr *NumThreads,
                                          SourceLocation StartLoc,
                                          SourceLocation LParenLoc,
                                          SourceLocation EndLoc);
   /// Called on well-formed 'safelen' clause.
   OMPClause *ActOnOpenMPSafelenClause(Expr *Length,
                                       SourceLocation StartLoc,
                                       SourceLocation LParenLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'simdlen' clause.
   OMPClause *ActOnOpenMPSimdlenClause(Expr *Length, SourceLocation StartLoc,
                                       SourceLocation LParenLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'collapse' clause.
   OMPClause *ActOnOpenMPCollapseClause(Expr *NumForLoops,
                                        SourceLocation StartLoc,
                                        SourceLocation LParenLoc,
                                        SourceLocation EndLoc);
   /// Called on well-formed 'ordered' clause.
   OMPClause *
   ActOnOpenMPOrderedClause(SourceLocation StartLoc, SourceLocation EndLoc,
                            SourceLocation LParenLoc = SourceLocation(),
                            Expr *NumForLoops = nullptr);
   /// Called on well-formed 'grainsize' clause.
   OMPClause *ActOnOpenMPGrainsizeClause(Expr *Size, SourceLocation StartLoc,
                                         SourceLocation LParenLoc,
                                         SourceLocation EndLoc);
   /// Called on well-formed 'num_tasks' clause.
   OMPClause *ActOnOpenMPNumTasksClause(Expr *NumTasks, SourceLocation StartLoc,
                                        SourceLocation LParenLoc,
                                        SourceLocation EndLoc);
   /// Called on well-formed 'hint' clause.
   OMPClause *ActOnOpenMPHintClause(Expr *Hint, SourceLocation StartLoc,
                                    SourceLocation LParenLoc,
                                    SourceLocation EndLoc);
   /// Called on well-formed 'detach' clause.
   OMPClause *ActOnOpenMPDetachClause(Expr *Evt, SourceLocation StartLoc,
                                      SourceLocation LParenLoc,
                                      SourceLocation EndLoc);
 
   OMPClause *ActOnOpenMPSimpleClause(OpenMPClauseKind Kind,
                                      unsigned Argument,
                                      SourceLocation ArgumentLoc,
                                      SourceLocation StartLoc,
                                      SourceLocation LParenLoc,
                                      SourceLocation EndLoc);
   /// Called on well-formed 'default' clause.
   OMPClause *ActOnOpenMPDefaultClause(llvm::omp::DefaultKind Kind,
                                       SourceLocation KindLoc,
                                       SourceLocation StartLoc,
                                       SourceLocation LParenLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'proc_bind' clause.
   OMPClause *ActOnOpenMPProcBindClause(llvm::omp::ProcBindKind Kind,
                                        SourceLocation KindLoc,
                                        SourceLocation StartLoc,
                                        SourceLocation LParenLoc,
                                        SourceLocation EndLoc);
   /// Called on well-formed 'order' clause.
   OMPClause *ActOnOpenMPOrderClause(OpenMPOrderClauseKind Kind,
                                     SourceLocation KindLoc,
                                     SourceLocation StartLoc,
                                     SourceLocation LParenLoc,
                                     SourceLocation EndLoc);
   /// Called on well-formed 'update' clause.
   OMPClause *ActOnOpenMPUpdateClause(OpenMPDependClauseKind Kind,
                                      SourceLocation KindLoc,
                                      SourceLocation StartLoc,
                                      SourceLocation LParenLoc,
                                      SourceLocation EndLoc);
 
   OMPClause *ActOnOpenMPSingleExprWithArgClause(
       OpenMPClauseKind Kind, ArrayRef<unsigned> Arguments, Expr *Expr,
       SourceLocation StartLoc, SourceLocation LParenLoc,
       ArrayRef<SourceLocation> ArgumentsLoc, SourceLocation DelimLoc,
       SourceLocation EndLoc);
   /// Called on well-formed 'schedule' clause.
   OMPClause *ActOnOpenMPScheduleClause(
       OpenMPScheduleClauseModifier M1, OpenMPScheduleClauseModifier M2,
       OpenMPScheduleClauseKind Kind, Expr *ChunkSize, SourceLocation StartLoc,
       SourceLocation LParenLoc, SourceLocation M1Loc, SourceLocation M2Loc,
       SourceLocation KindLoc, SourceLocation CommaLoc, SourceLocation EndLoc);
 
   OMPClause *ActOnOpenMPClause(OpenMPClauseKind Kind, SourceLocation StartLoc,
                                SourceLocation EndLoc);
   /// Called on well-formed 'nowait' clause.
   OMPClause *ActOnOpenMPNowaitClause(SourceLocation StartLoc,
                                      SourceLocation EndLoc);
   /// Called on well-formed 'untied' clause.
   OMPClause *ActOnOpenMPUntiedClause(SourceLocation StartLoc,
                                      SourceLocation EndLoc);
   /// Called on well-formed 'mergeable' clause.
   OMPClause *ActOnOpenMPMergeableClause(SourceLocation StartLoc,
                                         SourceLocation EndLoc);
   /// Called on well-formed 'read' clause.
   OMPClause *ActOnOpenMPReadClause(SourceLocation StartLoc,
                                    SourceLocation EndLoc);
   /// Called on well-formed 'write' clause.
   OMPClause *ActOnOpenMPWriteClause(SourceLocation StartLoc,
                                     SourceLocation EndLoc);
   /// Called on well-formed 'update' clause.
   OMPClause *ActOnOpenMPUpdateClause(SourceLocation StartLoc,
                                      SourceLocation EndLoc);
   /// Called on well-formed 'capture' clause.
   OMPClause *ActOnOpenMPCaptureClause(SourceLocation StartLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'seq_cst' clause.
   OMPClause *ActOnOpenMPSeqCstClause(SourceLocation StartLoc,
                                      SourceLocation EndLoc);
   /// Called on well-formed 'acq_rel' clause.
   OMPClause *ActOnOpenMPAcqRelClause(SourceLocation StartLoc,
                                      SourceLocation EndLoc);
   /// Called on well-formed 'acquire' clause.
   OMPClause *ActOnOpenMPAcquireClause(SourceLocation StartLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'release' clause.
   OMPClause *ActOnOpenMPReleaseClause(SourceLocation StartLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'relaxed' clause.
   OMPClause *ActOnOpenMPRelaxedClause(SourceLocation StartLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'destroy' clause.
   OMPClause *ActOnOpenMPDestroyClause(SourceLocation StartLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'threads' clause.
   OMPClause *ActOnOpenMPThreadsClause(SourceLocation StartLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'simd' clause.
   OMPClause *ActOnOpenMPSIMDClause(SourceLocation StartLoc,
                                    SourceLocation EndLoc);
   /// Called on well-formed 'nogroup' clause.
   OMPClause *ActOnOpenMPNogroupClause(SourceLocation StartLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'unified_address' clause.
   OMPClause *ActOnOpenMPUnifiedAddressClause(SourceLocation StartLoc,
                                              SourceLocation EndLoc);
 
   /// Called on well-formed 'unified_address' clause.
   OMPClause *ActOnOpenMPUnifiedSharedMemoryClause(SourceLocation StartLoc,
                                                   SourceLocation EndLoc);
 
   /// Called on well-formed 'reverse_offload' clause.
   OMPClause *ActOnOpenMPReverseOffloadClause(SourceLocation StartLoc,
                                              SourceLocation EndLoc);
 
   /// Called on well-formed 'dynamic_allocators' clause.
   OMPClause *ActOnOpenMPDynamicAllocatorsClause(SourceLocation StartLoc,
                                                 SourceLocation EndLoc);
 
   /// Called on well-formed 'atomic_default_mem_order' clause.
   OMPClause *ActOnOpenMPAtomicDefaultMemOrderClause(
       OpenMPAtomicDefaultMemOrderClauseKind Kind, SourceLocation KindLoc,
       SourceLocation StartLoc, SourceLocation LParenLoc, SourceLocation EndLoc);
 
   OMPClause *ActOnOpenMPVarListClause(
       OpenMPClauseKind Kind, ArrayRef<Expr *> Vars, Expr *TailExpr,
       const OMPVarListLocTy &Locs, SourceLocation ColonLoc,
       CXXScopeSpec &ReductionOrMapperIdScopeSpec,
       DeclarationNameInfo &ReductionOrMapperId, int ExtraModifier,
       ArrayRef<OpenMPMapModifierKind> MapTypeModifiers,
       ArrayRef<SourceLocation> MapTypeModifiersLoc, bool IsMapTypeImplicit,
       SourceLocation DepLinMapLastLoc);
   /// Called on well-formed 'allocate' clause.
   OMPClause *
   ActOnOpenMPAllocateClause(Expr *Allocator, ArrayRef<Expr *> VarList,
                             SourceLocation StartLoc, SourceLocation ColonLoc,
                             SourceLocation LParenLoc, SourceLocation EndLoc);
   /// Called on well-formed 'private' clause.
   OMPClause *ActOnOpenMPPrivateClause(ArrayRef<Expr *> VarList,
                                       SourceLocation StartLoc,
                                       SourceLocation LParenLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'firstprivate' clause.
   OMPClause *ActOnOpenMPFirstprivateClause(ArrayRef<Expr *> VarList,
                                            SourceLocation StartLoc,
                                            SourceLocation LParenLoc,
                                            SourceLocation EndLoc);
   /// Called on well-formed 'lastprivate' clause.
   OMPClause *ActOnOpenMPLastprivateClause(
       ArrayRef<Expr *> VarList, OpenMPLastprivateModifier LPKind,
       SourceLocation LPKindLoc, SourceLocation ColonLoc,
       SourceLocation StartLoc, SourceLocation LParenLoc, SourceLocation EndLoc);
   /// Called on well-formed 'shared' clause.
   OMPClause *ActOnOpenMPSharedClause(ArrayRef<Expr *> VarList,
                                      SourceLocation StartLoc,
                                      SourceLocation LParenLoc,
                                      SourceLocation EndLoc);
   /// Called on well-formed 'reduction' clause.
   OMPClause *ActOnOpenMPReductionClause(
       ArrayRef<Expr *> VarList, SourceLocation StartLoc,
       SourceLocation LParenLoc, SourceLocation ColonLoc, SourceLocation EndLoc,
       CXXScopeSpec &ReductionIdScopeSpec,
       const DeclarationNameInfo &ReductionId,
       ArrayRef<Expr *> UnresolvedReductions = llvm::None);
   /// Called on well-formed 'task_reduction' clause.
   OMPClause *ActOnOpenMPTaskReductionClause(
       ArrayRef<Expr *> VarList, SourceLocation StartLoc,
       SourceLocation LParenLoc, SourceLocation ColonLoc, SourceLocation EndLoc,
       CXXScopeSpec &ReductionIdScopeSpec,
       const DeclarationNameInfo &ReductionId,
       ArrayRef<Expr *> UnresolvedReductions = llvm::None);
   /// Called on well-formed 'in_reduction' clause.
   OMPClause *ActOnOpenMPInReductionClause(
       ArrayRef<Expr *> VarList, SourceLocation StartLoc,
       SourceLocation LParenLoc, SourceLocation ColonLoc, SourceLocation EndLoc,
       CXXScopeSpec &ReductionIdScopeSpec,
       const DeclarationNameInfo &ReductionId,
       ArrayRef<Expr *> UnresolvedReductions = llvm::None);
   /// Called on well-formed 'linear' clause.
   OMPClause *
   ActOnOpenMPLinearClause(ArrayRef<Expr *> VarList, Expr *Step,
                           SourceLocation StartLoc, SourceLocation LParenLoc,
                           OpenMPLinearClauseKind LinKind, SourceLocation LinLoc,
                           SourceLocation ColonLoc, SourceLocation EndLoc);
   /// Called on well-formed 'aligned' clause.
   OMPClause *ActOnOpenMPAlignedClause(ArrayRef<Expr *> VarList,
                                       Expr *Alignment,
                                       SourceLocation StartLoc,
                                       SourceLocation LParenLoc,
                                       SourceLocation ColonLoc,
                                       SourceLocation EndLoc);
   /// Called on well-formed 'copyin' clause.
   OMPClause *ActOnOpenMPCopyinClause(ArrayRef<Expr *> VarList,
                                      SourceLocation StartLoc,
                                      SourceLocation LParenLoc,
                                      SourceLocation EndLoc);
   /// Called on well-formed 'copyprivate' clause.
   OMPClause *ActOnOpenMPCopyprivateClause(ArrayRef<Expr *> VarList,
                                           SourceLocation StartLoc,
                                           SourceLocation LParenLoc,
                                           SourceLocation EndLoc);
   /// Called on well-formed 'flush' pseudo clause.
   OMPClause *ActOnOpenMPFlushClause(ArrayRef<Expr *> VarList,
                                     SourceLocation StartLoc,
                                     SourceLocation LParenLoc,
                                     SourceLocation EndLoc);
   /// Called on well-formed 'depobj' pseudo clause.
   OMPClause *ActOnOpenMPDepobjClause(Expr *Depobj, SourceLocation StartLoc,
                                      SourceLocation LParenLoc,
                                      SourceLocation EndLoc);
   /// Called on well-formed 'depend' clause.
   OMPClause *
   ActOnOpenMPDependClause(OpenMPDependClauseKind DepKind, SourceLocation DepLoc,
                           SourceLocation ColonLoc, ArrayRef<Expr *> VarList,
                           SourceLocation StartLoc, SourceLocation LParenLoc,
                           SourceLocation EndLoc);
   /// Called on well-formed 'device' clause.
-  OMPClause *ActOnOpenMPDeviceClause(Expr *Device, SourceLocation StartLoc,
+  OMPClause *ActOnOpenMPDeviceClause(OpenMPDeviceClauseModifier Modifier,
+                                     Expr *Device, SourceLocation StartLoc,
                                      SourceLocation LParenLoc,
+                                     SourceLocation ModifierLoc,
                                      SourceLocation EndLoc);
   /// Called on well-formed 'map' clause.
   OMPClause *
   ActOnOpenMPMapClause(ArrayRef<OpenMPMapModifierKind> MapTypeModifiers,
                        ArrayRef<SourceLocation> MapTypeModifiersLoc,
                        CXXScopeSpec &MapperIdScopeSpec,
                        DeclarationNameInfo &MapperId,
                        OpenMPMapClauseKind MapType, bool IsMapTypeImplicit,
                        SourceLocation MapLoc, SourceLocation ColonLoc,
                        ArrayRef<Expr *> VarList, const OMPVarListLocTy &Locs,
                        ArrayRef<Expr *> UnresolvedMappers = llvm::None);
   /// Called on well-formed 'num_teams' clause.
   OMPClause *ActOnOpenMPNumTeamsClause(Expr *NumTeams, SourceLocation StartLoc,
                                        SourceLocation LParenLoc,
                                        SourceLocation EndLoc);
   /// Called on well-formed 'thread_limit' clause.
   OMPClause *ActOnOpenMPThreadLimitClause(Expr *ThreadLimit,
                                           SourceLocation StartLoc,
                                           SourceLocation LParenLoc,
                                           SourceLocation EndLoc);
   /// Called on well-formed 'priority' clause.
   OMPClause *ActOnOpenMPPriorityClause(Expr *Priority, SourceLocation StartLoc,
                                        SourceLocation LParenLoc,
                                        SourceLocation EndLoc);
   /// Called on well-formed 'dist_schedule' clause.
   OMPClause *ActOnOpenMPDistScheduleClause(
       OpenMPDistScheduleClauseKind Kind, Expr *ChunkSize,
       SourceLocation StartLoc, SourceLocation LParenLoc, SourceLocation KindLoc,
       SourceLocation CommaLoc, SourceLocation EndLoc);
   /// Called on well-formed 'defaultmap' clause.
   OMPClause *ActOnOpenMPDefaultmapClause(
       OpenMPDefaultmapClauseModifier M, OpenMPDefaultmapClauseKind Kind,
       SourceLocation StartLoc, SourceLocation LParenLoc, SourceLocation MLoc,
       SourceLocation KindLoc, SourceLocation EndLoc);
   /// Called on well-formed 'to' clause.
   OMPClause *
   ActOnOpenMPToClause(ArrayRef<Expr *> VarList, CXXScopeSpec &MapperIdScopeSpec,
                       DeclarationNameInfo &MapperId,
                       const OMPVarListLocTy &Locs,
                       ArrayRef<Expr *> UnresolvedMappers = llvm::None);
   /// Called on well-formed 'from' clause.
   OMPClause *ActOnOpenMPFromClause(
       ArrayRef<Expr *> VarList, CXXScopeSpec &MapperIdScopeSpec,
       DeclarationNameInfo &MapperId, const OMPVarListLocTy &Locs,
       ArrayRef<Expr *> UnresolvedMappers = llvm::None);
   /// Called on well-formed 'use_device_ptr' clause.
   OMPClause *ActOnOpenMPUseDevicePtrClause(ArrayRef<Expr *> VarList,
                                            const OMPVarListLocTy &Locs);
   /// Called on well-formed 'is_device_ptr' clause.
   OMPClause *ActOnOpenMPIsDevicePtrClause(ArrayRef<Expr *> VarList,
                                           const OMPVarListLocTy &Locs);
   /// Called on well-formed 'nontemporal' clause.
   OMPClause *ActOnOpenMPNontemporalClause(ArrayRef<Expr *> VarList,
                                           SourceLocation StartLoc,
                                           SourceLocation LParenLoc,
                                           SourceLocation EndLoc);
 
   /// The kind of conversion being performed.
   enum CheckedConversionKind {
     /// An implicit conversion.
     CCK_ImplicitConversion,
     /// A C-style cast.
     CCK_CStyleCast,
     /// A functional-style cast.
     CCK_FunctionalCast,
     /// A cast other than a C-style cast.
     CCK_OtherCast,
     /// A conversion for an operand of a builtin overloaded operator.
     CCK_ForBuiltinOverloadedOp
   };
 
   static bool isCast(CheckedConversionKind CCK) {
     return CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast ||
            CCK == CCK_OtherCast;
   }
 
   /// ImpCastExprToType - If Expr is not of type 'Type', insert an implicit
   /// cast.  If there is already an implicit cast, merge into the existing one.
   /// If isLvalue, the result of the cast is an lvalue.
   ExprResult ImpCastExprToType(Expr *E, QualType Type, CastKind CK,
                                ExprValueKind VK = VK_RValue,
                                const CXXCastPath *BasePath = nullptr,
                                CheckedConversionKind CCK
                                   = CCK_ImplicitConversion);
 
   /// ScalarTypeToBooleanCastKind - Returns the cast kind corresponding
   /// to the conversion from scalar type ScalarTy to the Boolean type.
   static CastKind ScalarTypeToBooleanCastKind(QualType ScalarTy);
 
   /// IgnoredValueConversions - Given that an expression's result is
   /// syntactically ignored, perform any conversions that are
   /// required.
   ExprResult IgnoredValueConversions(Expr *E);
 
   // UsualUnaryConversions - promotes integers (C99 6.3.1.1p2) and converts
   // functions and arrays to their respective pointers (C99 6.3.2.1).
   ExprResult UsualUnaryConversions(Expr *E);
 
   /// CallExprUnaryConversions - a special case of an unary conversion
   /// performed on a function designator of a call expression.
   ExprResult CallExprUnaryConversions(Expr *E);
 
   // DefaultFunctionArrayConversion - converts functions and arrays
   // to their respective pointers (C99 6.3.2.1).
   ExprResult DefaultFunctionArrayConversion(Expr *E, bool Diagnose = true);
 
   // DefaultFunctionArrayLvalueConversion - converts functions and
   // arrays to their respective pointers and performs the
   // lvalue-to-rvalue conversion.
   ExprResult DefaultFunctionArrayLvalueConversion(Expr *E,
                                                   bool Diagnose = true);
 
   // DefaultLvalueConversion - performs lvalue-to-rvalue conversion on
   // the operand.  This is DefaultFunctionArrayLvalueConversion,
   // except that it assumes the operand isn't of function or array
   // type.
   ExprResult DefaultLvalueConversion(Expr *E);
 
   // DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that
   // do not have a prototype. Integer promotions are performed on each
   // argument, and arguments that have type float are promoted to double.
   ExprResult DefaultArgumentPromotion(Expr *E);
 
   /// If \p E is a prvalue denoting an unmaterialized temporary, materialize
   /// it as an xvalue. In C++98, the result will still be a prvalue, because
   /// we don't have xvalues there.
   ExprResult TemporaryMaterializationConversion(Expr *E);
 
   // Used for emitting the right warning by DefaultVariadicArgumentPromotion
   enum VariadicCallType {
     VariadicFunction,
     VariadicBlock,
     VariadicMethod,
     VariadicConstructor,
     VariadicDoesNotApply
   };
 
   VariadicCallType getVariadicCallType(FunctionDecl *FDecl,
                                        const FunctionProtoType *Proto,
                                        Expr *Fn);
 
   // Used for determining in which context a type is allowed to be passed to a
   // vararg function.
   enum VarArgKind {
     VAK_Valid,
     VAK_ValidInCXX11,
     VAK_Undefined,
     VAK_MSVCUndefined,
     VAK_Invalid
   };
 
   // Determines which VarArgKind fits an expression.
   VarArgKind isValidVarArgType(const QualType &Ty);
 
   /// Check to see if the given expression is a valid argument to a variadic
   /// function, issuing a diagnostic if not.
   void checkVariadicArgument(const Expr *E, VariadicCallType CT);
 
   /// Check to see if a given expression could have '.c_str()' called on it.
   bool hasCStrMethod(const Expr *E);
 
   /// GatherArgumentsForCall - Collector argument expressions for various
   /// form of call prototypes.
   bool GatherArgumentsForCall(SourceLocation CallLoc, FunctionDecl *FDecl,
                               const FunctionProtoType *Proto,
                               unsigned FirstParam, ArrayRef<Expr *> Args,
                               SmallVectorImpl<Expr *> &AllArgs,
                               VariadicCallType CallType = VariadicDoesNotApply,
                               bool AllowExplicit = false,
                               bool IsListInitialization = false);
 
   // DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but
   // will create a runtime trap if the resulting type is not a POD type.
   ExprResult DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT,
                                               FunctionDecl *FDecl);
 
   /// Context in which we're performing a usual arithmetic conversion.
   enum ArithConvKind {
     /// An arithmetic operation.
     ACK_Arithmetic,
     /// A bitwise operation.
     ACK_BitwiseOp,
     /// A comparison.
     ACK_Comparison,
     /// A conditional (?:) operator.
     ACK_Conditional,
     /// A compound assignment expression.
     ACK_CompAssign,
   };
 
   // UsualArithmeticConversions - performs the UsualUnaryConversions on it's
   // operands and then handles various conversions that are common to binary
   // operators (C99 6.3.1.8). If both operands aren't arithmetic, this
   // routine returns the first non-arithmetic type found. The client is
   // responsible for emitting appropriate error diagnostics.
   QualType UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS,
                                       SourceLocation Loc, ArithConvKind ACK);
 
   /// AssignConvertType - All of the 'assignment' semantic checks return this
   /// enum to indicate whether the assignment was allowed.  These checks are
   /// done for simple assignments, as well as initialization, return from
   /// function, argument passing, etc.  The query is phrased in terms of a
   /// source and destination type.
   enum AssignConvertType {
     /// Compatible - the types are compatible according to the standard.
     Compatible,
 
     /// PointerToInt - The assignment converts a pointer to an int, which we
     /// accept as an extension.
     PointerToInt,
 
     /// IntToPointer - The assignment converts an int to a pointer, which we
     /// accept as an extension.
     IntToPointer,
 
     /// FunctionVoidPointer - The assignment is between a function pointer and
     /// void*, which the standard doesn't allow, but we accept as an extension.
     FunctionVoidPointer,
 
     /// IncompatiblePointer - The assignment is between two pointers types that
     /// are not compatible, but we accept them as an extension.
     IncompatiblePointer,
 
     /// IncompatibleFunctionPointer - The assignment is between two function
     /// pointers types that are not compatible, but we accept them as an
     /// extension.
     IncompatibleFunctionPointer,
 
     /// IncompatiblePointerSign - The assignment is between two pointers types
     /// which point to integers which have a different sign, but are otherwise
     /// identical. This is a subset of the above, but broken out because it's by
     /// far the most common case of incompatible pointers.
     IncompatiblePointerSign,
 
     /// CompatiblePointerDiscardsQualifiers - The assignment discards
     /// c/v/r qualifiers, which we accept as an extension.
     CompatiblePointerDiscardsQualifiers,
 
     /// IncompatiblePointerDiscardsQualifiers - The assignment
     /// discards qualifiers that we don't permit to be discarded,
     /// like address spaces.
     IncompatiblePointerDiscardsQualifiers,
 
     /// IncompatibleNestedPointerAddressSpaceMismatch - The assignment
     /// changes address spaces in nested pointer types which is not allowed.
     /// For instance, converting __private int ** to __generic int ** is
     /// illegal even though __private could be converted to __generic.
     IncompatibleNestedPointerAddressSpaceMismatch,
 
     /// IncompatibleNestedPointerQualifiers - The assignment is between two
     /// nested pointer types, and the qualifiers other than the first two
     /// levels differ e.g. char ** -> const char **, but we accept them as an
     /// extension.
     IncompatibleNestedPointerQualifiers,
 
     /// IncompatibleVectors - The assignment is between two vector types that
     /// have the same size, which we accept as an extension.
     IncompatibleVectors,
 
     /// IntToBlockPointer - The assignment converts an int to a block
     /// pointer. We disallow this.
     IntToBlockPointer,
 
     /// IncompatibleBlockPointer - The assignment is between two block
     /// pointers types that are not compatible.
     IncompatibleBlockPointer,
 
     /// IncompatibleObjCQualifiedId - The assignment is between a qualified
     /// id type and something else (that is incompatible with it). For example,
     /// "id <XXX>" = "Foo *", where "Foo *" doesn't implement the XXX protocol.
     IncompatibleObjCQualifiedId,
 
     /// IncompatibleObjCWeakRef - Assigning a weak-unavailable object to an
     /// object with __weak qualifier.
     IncompatibleObjCWeakRef,
 
     /// Incompatible - We reject this conversion outright, it is invalid to
     /// represent it in the AST.
     Incompatible
   };
 
   /// DiagnoseAssignmentResult - Emit a diagnostic, if required, for the
   /// assignment conversion type specified by ConvTy.  This returns true if the
   /// conversion was invalid or false if the conversion was accepted.
   bool DiagnoseAssignmentResult(AssignConvertType ConvTy,
                                 SourceLocation Loc,
                                 QualType DstType, QualType SrcType,
                                 Expr *SrcExpr, AssignmentAction Action,
                                 bool *Complained = nullptr);
 
   /// IsValueInFlagEnum - Determine if a value is allowed as part of a flag
   /// enum. If AllowMask is true, then we also allow the complement of a valid
   /// value, to be used as a mask.
   bool IsValueInFlagEnum(const EnumDecl *ED, const llvm::APInt &Val,
                          bool AllowMask) const;
 
   /// DiagnoseAssignmentEnum - Warn if assignment to enum is a constant
   /// integer not in the range of enum values.
   void DiagnoseAssignmentEnum(QualType DstType, QualType SrcType,
                               Expr *SrcExpr);
 
   /// CheckAssignmentConstraints - Perform type checking for assignment,
   /// argument passing, variable initialization, and function return values.
   /// C99 6.5.16.
   AssignConvertType CheckAssignmentConstraints(SourceLocation Loc,
                                                QualType LHSType,
                                                QualType RHSType);
 
   /// Check assignment constraints and optionally prepare for a conversion of
   /// the RHS to the LHS type. The conversion is prepared for if ConvertRHS
   /// is true.
   AssignConvertType CheckAssignmentConstraints(QualType LHSType,
                                                ExprResult &RHS,
                                                CastKind &Kind,
                                                bool ConvertRHS = true);
 
   /// Check assignment constraints for an assignment of RHS to LHSType.
   ///
   /// \param LHSType The destination type for the assignment.
   /// \param RHS The source expression for the assignment.
   /// \param Diagnose If \c true, diagnostics may be produced when checking
   ///        for assignability. If a diagnostic is produced, \p RHS will be
   ///        set to ExprError(). Note that this function may still return
   ///        without producing a diagnostic, even for an invalid assignment.
   /// \param DiagnoseCFAudited If \c true, the target is a function parameter
   ///        in an audited Core Foundation API and does not need to be checked
   ///        for ARC retain issues.
   /// \param ConvertRHS If \c true, \p RHS will be updated to model the
   ///        conversions necessary to perform the assignment. If \c false,
   ///        \p Diagnose must also be \c false.
   AssignConvertType CheckSingleAssignmentConstraints(
       QualType LHSType, ExprResult &RHS, bool Diagnose = true,
       bool DiagnoseCFAudited = false, bool ConvertRHS = true);
 
   // If the lhs type is a transparent union, check whether we
   // can initialize the transparent union with the given expression.
   AssignConvertType CheckTransparentUnionArgumentConstraints(QualType ArgType,
                                                              ExprResult &RHS);
 
   bool IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType);
 
   bool CheckExceptionSpecCompatibility(Expr *From, QualType ToType);
 
   ExprResult PerformImplicitConversion(Expr *From, QualType ToType,
                                        AssignmentAction Action,
                                        bool AllowExplicit = false);
   ExprResult PerformImplicitConversion(Expr *From, QualType ToType,
                                        AssignmentAction Action,
                                        bool AllowExplicit,
                                        ImplicitConversionSequence& ICS);
   ExprResult PerformImplicitConversion(Expr *From, QualType ToType,
                                        const ImplicitConversionSequence& ICS,
                                        AssignmentAction Action,
                                        CheckedConversionKind CCK
                                           = CCK_ImplicitConversion);
   ExprResult PerformImplicitConversion(Expr *From, QualType ToType,
                                        const StandardConversionSequence& SCS,
                                        AssignmentAction Action,
                                        CheckedConversionKind CCK);
 
   ExprResult PerformQualificationConversion(
       Expr *E, QualType Ty, ExprValueKind VK = VK_RValue,
       CheckedConversionKind CCK = CCK_ImplicitConversion);
 
   /// the following "Check" methods will return a valid/converted QualType
   /// or a null QualType (indicating an error diagnostic was issued).
 
   /// type checking binary operators (subroutines of CreateBuiltinBinOp).
   QualType InvalidOperands(SourceLocation Loc, ExprResult &LHS,
                            ExprResult &RHS);
   QualType InvalidLogicalVectorOperands(SourceLocation Loc, ExprResult &LHS,
                                  ExprResult &RHS);
   QualType CheckPointerToMemberOperands( // C++ 5.5
     ExprResult &LHS, ExprResult &RHS, ExprValueKind &VK,
     SourceLocation OpLoc, bool isIndirect);
   QualType CheckMultiplyDivideOperands( // C99 6.5.5
     ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign,
     bool IsDivide);
   QualType CheckRemainderOperands( // C99 6.5.5
     ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
     bool IsCompAssign = false);
   QualType CheckAdditionOperands( // C99 6.5.6
     ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
     BinaryOperatorKind Opc, QualType* CompLHSTy = nullptr);
   QualType CheckSubtractionOperands( // C99 6.5.6
     ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
     QualType* CompLHSTy = nullptr);
   QualType CheckShiftOperands( // C99 6.5.7
     ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
     BinaryOperatorKind Opc, bool IsCompAssign = false);
   void CheckPtrComparisonWithNullChar(ExprResult &E, ExprResult &NullE);
   QualType CheckCompareOperands( // C99 6.5.8/9
       ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
       BinaryOperatorKind Opc);
   QualType CheckBitwiseOperands( // C99 6.5.[10...12]
       ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
       BinaryOperatorKind Opc);
   QualType CheckLogicalOperands( // C99 6.5.[13,14]
     ExprResult &LHS, ExprResult &RHS, SourceLocation Loc,
     BinaryOperatorKind Opc);
   // CheckAssignmentOperands is used for both simple and compound assignment.
   // For simple assignment, pass both expressions and a null converted type.
   // For compound assignment, pass both expressions and the converted type.
   QualType CheckAssignmentOperands( // C99 6.5.16.[1,2]
     Expr *LHSExpr, ExprResult &RHS, SourceLocation Loc, QualType CompoundType);
 
   ExprResult checkPseudoObjectIncDec(Scope *S, SourceLocation OpLoc,
                                      UnaryOperatorKind Opcode, Expr *Op);
   ExprResult checkPseudoObjectAssignment(Scope *S, SourceLocation OpLoc,
                                          BinaryOperatorKind Opcode,
                                          Expr *LHS, Expr *RHS);
   ExprResult checkPseudoObjectRValue(Expr *E);
   Expr *recreateSyntacticForm(PseudoObjectExpr *E);
 
   QualType CheckConditionalOperands( // C99 6.5.15
     ExprResult &Cond, ExprResult &LHS, ExprResult &RHS,
     ExprValueKind &VK, ExprObjectKind &OK, SourceLocation QuestionLoc);
   QualType CXXCheckConditionalOperands( // C++ 5.16
     ExprResult &cond, ExprResult &lhs, ExprResult &rhs,
     ExprValueKind &VK, ExprObjectKind &OK, SourceLocation questionLoc);
   QualType CheckGNUVectorConditionalTypes(ExprResult &Cond, ExprResult &LHS,
                                           ExprResult &RHS,
                                           SourceLocation QuestionLoc);
   QualType FindCompositePointerType(SourceLocation Loc, Expr *&E1, Expr *&E2,
                                     bool ConvertArgs = true);
   QualType FindCompositePointerType(SourceLocation Loc,
                                     ExprResult &E1, ExprResult &E2,
                                     bool ConvertArgs = true) {
     Expr *E1Tmp = E1.get(), *E2Tmp = E2.get();
     QualType Composite =
         FindCompositePointerType(Loc, E1Tmp, E2Tmp, ConvertArgs);
     E1 = E1Tmp;
     E2 = E2Tmp;
     return Composite;
   }
 
   QualType FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS,
                                         SourceLocation QuestionLoc);
 
   bool DiagnoseConditionalForNull(Expr *LHSExpr, Expr *RHSExpr,
                                   SourceLocation QuestionLoc);
 
   void DiagnoseAlwaysNonNullPointer(Expr *E,
                                     Expr::NullPointerConstantKind NullType,
                                     bool IsEqual, SourceRange Range);
 
   /// type checking for vector binary operators.
   QualType CheckVectorOperands(ExprResult &LHS, ExprResult &RHS,
                                SourceLocation Loc, bool IsCompAssign,
                                bool AllowBothBool, bool AllowBoolConversion);
   QualType GetSignedVectorType(QualType V);
   QualType CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS,
                                       SourceLocation Loc,
                                       BinaryOperatorKind Opc);
   QualType CheckVectorLogicalOperands(ExprResult &LHS, ExprResult &RHS,
                                       SourceLocation Loc);
 
   bool areLaxCompatibleVectorTypes(QualType srcType, QualType destType);
   bool isLaxVectorConversion(QualType srcType, QualType destType);
 
   /// type checking declaration initializers (C99 6.7.8)
   bool CheckForConstantInitializer(Expr *e, QualType t);
 
   // type checking C++ declaration initializers (C++ [dcl.init]).
 
   /// ReferenceCompareResult - Expresses the result of comparing two
   /// types (cv1 T1 and cv2 T2) to determine their compatibility for the
   /// purposes of initialization by reference (C++ [dcl.init.ref]p4).
   enum ReferenceCompareResult {
     /// Ref_Incompatible - The two types are incompatible, so direct
     /// reference binding is not possible.
     Ref_Incompatible = 0,
     /// Ref_Related - The two types are reference-related, which means
     /// that their unqualified forms (T1 and T2) are either the same
     /// or T1 is a base class of T2.
     Ref_Related,
     /// Ref_Compatible - The two types are reference-compatible.
     Ref_Compatible
   };
 
   // Fake up a scoped enumeration that still contextually converts to bool.
   struct ReferenceConversionsScope {
     /// The conversions that would be performed on an lvalue of type T2 when
     /// binding a reference of type T1 to it, as determined when evaluating
     /// whether T1 is reference-compatible with T2.
     enum ReferenceConversions {
       Qualification = 0x1,
       NestedQualification = 0x2,
       Function = 0x4,
       DerivedToBase = 0x8,
       ObjC = 0x10,
       ObjCLifetime = 0x20,
 
       LLVM_MARK_AS_BITMASK_ENUM(/*LargestValue=*/ObjCLifetime)
     };
   };
   using ReferenceConversions = ReferenceConversionsScope::ReferenceConversions;
 
   ReferenceCompareResult
   CompareReferenceRelationship(SourceLocation Loc, QualType T1, QualType T2,
                                ReferenceConversions *Conv = nullptr);
 
   ExprResult checkUnknownAnyCast(SourceRange TypeRange, QualType CastType,
                                  Expr *CastExpr, CastKind &CastKind,
                                  ExprValueKind &VK, CXXCastPath &Path);
 
   /// Force an expression with unknown-type to an expression of the
   /// given type.
   ExprResult forceUnknownAnyToType(Expr *E, QualType ToType);
 
   /// Type-check an expression that's being passed to an
   /// __unknown_anytype parameter.
   ExprResult checkUnknownAnyArg(SourceLocation callLoc,
                                 Expr *result, QualType &paramType);
 
   // CheckVectorCast - check type constraints for vectors.
   // Since vectors are an extension, there are no C standard reference for this.
   // We allow casting between vectors and integer datatypes of the same size.
   // returns true if the cast is invalid
   bool CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty,
                        CastKind &Kind);
 
   /// Prepare `SplattedExpr` for a vector splat operation, adding
   /// implicit casts if necessary.
   ExprResult prepareVectorSplat(QualType VectorTy, Expr *SplattedExpr);
 
   // CheckExtVectorCast - check type constraints for extended vectors.
   // Since vectors are an extension, there are no C standard reference for this.
   // We allow casting between vectors and integer datatypes of the same size,
   // or vectors and the element type of that vector.
   // returns the cast expr
   ExprResult CheckExtVectorCast(SourceRange R, QualType DestTy, Expr *CastExpr,
                                 CastKind &Kind);
 
   ExprResult BuildCXXFunctionalCastExpr(TypeSourceInfo *TInfo, QualType Type,
                                         SourceLocation LParenLoc,
                                         Expr *CastExpr,
                                         SourceLocation RParenLoc);
 
   enum ARCConversionResult { ACR_okay, ACR_unbridged, ACR_error };
 
   /// Checks for invalid conversions and casts between
   /// retainable pointers and other pointer kinds for ARC and Weak.
   ARCConversionResult CheckObjCConversion(SourceRange castRange,
                                           QualType castType, Expr *&op,
                                           CheckedConversionKind CCK,
                                           bool Diagnose = true,
                                           bool DiagnoseCFAudited = false,
                                           BinaryOperatorKind Opc = BO_PtrMemD
                                           );
 
   Expr *stripARCUnbridgedCast(Expr *e);
   void diagnoseARCUnbridgedCast(Expr *e);
 
   bool CheckObjCARCUnavailableWeakConversion(QualType castType,
                                              QualType ExprType);
 
   /// checkRetainCycles - Check whether an Objective-C message send
   /// might create an obvious retain cycle.
   void checkRetainCycles(ObjCMessageExpr *msg);
   void checkRetainCycles(Expr *receiver, Expr *argument);
   void checkRetainCycles(VarDecl *Var, Expr *Init);
 
   /// checkUnsafeAssigns - Check whether +1 expr is being assigned
   /// to weak/__unsafe_unretained type.
   bool checkUnsafeAssigns(SourceLocation Loc, QualType LHS, Expr *RHS);
 
   /// checkUnsafeExprAssigns - Check whether +1 expr is being assigned
   /// to weak/__unsafe_unretained expression.
   void checkUnsafeExprAssigns(SourceLocation Loc, Expr *LHS, Expr *RHS);
 
   /// CheckMessageArgumentTypes - Check types in an Obj-C message send.
   /// \param Method - May be null.
   /// \param [out] ReturnType - The return type of the send.
   /// \return true iff there were any incompatible types.
   bool CheckMessageArgumentTypes(const Expr *Receiver, QualType ReceiverType,
                                  MultiExprArg Args, Selector Sel,
                                  ArrayRef<SourceLocation> SelectorLocs,
                                  ObjCMethodDecl *Method, bool isClassMessage,
                                  bool isSuperMessage, SourceLocation lbrac,
                                  SourceLocation rbrac, SourceRange RecRange,
                                  QualType &ReturnType, ExprValueKind &VK);
 
   /// Determine the result of a message send expression based on
   /// the type of the receiver, the method expected to receive the message,
   /// and the form of the message send.
   QualType getMessageSendResultType(const Expr *Receiver, QualType ReceiverType,
                                     ObjCMethodDecl *Method, bool isClassMessage,
                                     bool isSuperMessage);
 
   /// If the given expression involves a message send to a method
   /// with a related result type, emit a note describing what happened.
   void EmitRelatedResultTypeNote(const Expr *E);
 
   /// Given that we had incompatible pointer types in a return
   /// statement, check whether we're in a method with a related result
   /// type, and if so, emit a note describing what happened.
   void EmitRelatedResultTypeNoteForReturn(QualType destType);
 
   class ConditionResult {
     Decl *ConditionVar;
     FullExprArg Condition;
     bool Invalid;
     bool HasKnownValue;
     bool KnownValue;
 
     friend class Sema;
     ConditionResult(Sema &S, Decl *ConditionVar, FullExprArg Condition,
                     bool IsConstexpr)
         : ConditionVar(ConditionVar), Condition(Condition), Invalid(false),
           HasKnownValue(IsConstexpr && Condition.get() &&
                         !Condition.get()->isValueDependent()),
           KnownValue(HasKnownValue &&
                      !!Condition.get()->EvaluateKnownConstInt(S.Context)) {}
     explicit ConditionResult(bool Invalid)
         : ConditionVar(nullptr), Condition(nullptr), Invalid(Invalid),
           HasKnownValue(false), KnownValue(false) {}
 
   public:
     ConditionResult() : ConditionResult(false) {}
     bool isInvalid() const { return Invalid; }
     std::pair<VarDecl *, Expr *> get() const {
       return std::make_pair(cast_or_null<VarDecl>(ConditionVar),
                             Condition.get());
     }
     llvm::Optional<bool> getKnownValue() const {
       if (!HasKnownValue)
         return None;
       return KnownValue;
     }
   };
   static ConditionResult ConditionError() { return ConditionResult(true); }
 
   enum class ConditionKind {
     Boolean,     ///< A boolean condition, from 'if', 'while', 'for', or 'do'.
     ConstexprIf, ///< A constant boolean condition from 'if constexpr'.
     Switch       ///< An integral condition for a 'switch' statement.
   };
 
   ConditionResult ActOnCondition(Scope *S, SourceLocation Loc,
                                  Expr *SubExpr, ConditionKind CK);
 
   ConditionResult ActOnConditionVariable(Decl *ConditionVar,
                                          SourceLocation StmtLoc,
                                          ConditionKind CK);
 
   DeclResult ActOnCXXConditionDeclaration(Scope *S, Declarator &D);
 
   ExprResult CheckConditionVariable(VarDecl *ConditionVar,
                                     SourceLocation StmtLoc,
                                     ConditionKind CK);
   ExprResult CheckSwitchCondition(SourceLocation SwitchLoc, Expr *Cond);
 
   /// CheckBooleanCondition - Diagnose problems involving the use of
   /// the given expression as a boolean condition (e.g. in an if
   /// statement).  Also performs the standard function and array
   /// decays, possibly changing the input variable.
   ///
   /// \param Loc - A location associated with the condition, e.g. the
   /// 'if' keyword.
   /// \return true iff there were any errors
   ExprResult CheckBooleanCondition(SourceLocation Loc, Expr *E,
                                    bool IsConstexpr = false);
 
   /// ActOnExplicitBoolSpecifier - Build an ExplicitSpecifier from an expression
   /// found in an explicit(bool) specifier.
   ExplicitSpecifier ActOnExplicitBoolSpecifier(Expr *E);
 
   /// tryResolveExplicitSpecifier - Attempt to resolve the explict specifier.
   /// Returns true if the explicit specifier is now resolved.
   bool tryResolveExplicitSpecifier(ExplicitSpecifier &ExplicitSpec);
 
   /// DiagnoseAssignmentAsCondition - Given that an expression is
   /// being used as a boolean condition, warn if it's an assignment.
   void DiagnoseAssignmentAsCondition(Expr *E);
 
   /// Redundant parentheses over an equality comparison can indicate
   /// that the user intended an assignment used as condition.
   void DiagnoseEqualityWithExtraParens(ParenExpr *ParenE);
 
   /// CheckCXXBooleanCondition - Returns true if conversion to bool is invalid.
   ExprResult CheckCXXBooleanCondition(Expr *CondExpr, bool IsConstexpr = false);
 
   /// ConvertIntegerToTypeWarnOnOverflow - Convert the specified APInt to have
   /// the specified width and sign.  If an overflow occurs, detect it and emit
   /// the specified diagnostic.
   void ConvertIntegerToTypeWarnOnOverflow(llvm::APSInt &OldVal,
                                           unsigned NewWidth, bool NewSign,
                                           SourceLocation Loc, unsigned DiagID);
 
   /// Checks that the Objective-C declaration is declared in the global scope.
   /// Emits an error and marks the declaration as invalid if it's not declared
   /// in the global scope.
   bool CheckObjCDeclScope(Decl *D);
 
   /// Abstract base class used for diagnosing integer constant
   /// expression violations.
   class VerifyICEDiagnoser {
   public:
     bool Suppress;
 
     VerifyICEDiagnoser(bool Suppress = false) : Suppress(Suppress) { }
 
     virtual void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) =0;
     virtual void diagnoseFold(Sema &S, SourceLocation Loc, SourceRange SR);
     virtual ~VerifyICEDiagnoser() { }
   };
 
   /// VerifyIntegerConstantExpression - Verifies that an expression is an ICE,
   /// and reports the appropriate diagnostics. Returns false on success.
   /// Can optionally return the value of the expression.
   ExprResult VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
                                              VerifyICEDiagnoser &Diagnoser,
                                              bool AllowFold = true);
   ExprResult VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
                                              unsigned DiagID,
                                              bool AllowFold = true);
   ExprResult VerifyIntegerConstantExpression(Expr *E,
                                              llvm::APSInt *Result = nullptr);
 
   /// VerifyBitField - verifies that a bit field expression is an ICE and has
   /// the correct width, and that the field type is valid.
   /// Returns false on success.
   /// Can optionally return whether the bit-field is of width 0
   ExprResult VerifyBitField(SourceLocation FieldLoc, IdentifierInfo *FieldName,
                             QualType FieldTy, bool IsMsStruct,
                             Expr *BitWidth, bool *ZeroWidth = nullptr);
 
 private:
   unsigned ForceCUDAHostDeviceDepth = 0;
 
 public:
   /// Increments our count of the number of times we've seen a pragma forcing
   /// functions to be __host__ __device__.  So long as this count is greater
   /// than zero, all functions encountered will be __host__ __device__.
   void PushForceCUDAHostDevice();
 
   /// Decrements our count of the number of times we've seen a pragma forcing
   /// functions to be __host__ __device__.  Returns false if the count is 0
   /// before incrementing, so you can emit an error.
   bool PopForceCUDAHostDevice();
 
   /// Diagnostics that are emitted only if we discover that the given function
   /// must be codegen'ed.  Because handling these correctly adds overhead to
   /// compilation, this is currently only enabled for CUDA compilations.
   llvm::DenseMap<CanonicalDeclPtr<FunctionDecl>,
                  std::vector<PartialDiagnosticAt>>
       DeviceDeferredDiags;
 
   /// A pair of a canonical FunctionDecl and a SourceLocation.  When used as the
   /// key in a hashtable, both the FD and location are hashed.
   struct FunctionDeclAndLoc {
     CanonicalDeclPtr<FunctionDecl> FD;
     SourceLocation Loc;
   };
 
   /// FunctionDecls and SourceLocations for which CheckCUDACall has emitted a
   /// (maybe deferred) "bad call" diagnostic.  We use this to avoid emitting the
   /// same deferred diag twice.
   llvm::DenseSet<FunctionDeclAndLoc> LocsWithCUDACallDiags;
 
   /// An inverse call graph, mapping known-emitted functions to one of their
   /// known-emitted callers (plus the location of the call).
   ///
   /// Functions that we can tell a priori must be emitted aren't added to this
   /// map.
   llvm::DenseMap</* Callee = */ CanonicalDeclPtr<FunctionDecl>,
                  /* Caller = */ FunctionDeclAndLoc>
       DeviceKnownEmittedFns;
 
   /// A partial call graph maintained during CUDA/OpenMP device code compilation
   /// to support deferred diagnostics.
   ///
   /// Functions are only added here if, at the time they're considered, they are
   /// not known-emitted.  As soon as we discover that a function is
   /// known-emitted, we remove it and everything it transitively calls from this
   /// set and add those functions to DeviceKnownEmittedFns.
   llvm::DenseMap</* Caller = */ CanonicalDeclPtr<FunctionDecl>,
                  /* Callees = */ llvm::MapVector<CanonicalDeclPtr<FunctionDecl>,
                                                  SourceLocation>>
       DeviceCallGraph;
 
   /// Diagnostic builder for CUDA/OpenMP devices errors which may or may not be
   /// deferred.
   ///
   /// In CUDA, there exist constructs (e.g. variable-length arrays, try/catch)
   /// which are not allowed to appear inside __device__ functions and are
   /// allowed to appear in __host__ __device__ functions only if the host+device
   /// function is never codegen'ed.
   ///
   /// To handle this, we use the notion of "deferred diagnostics", where we
   /// attach a diagnostic to a FunctionDecl that's emitted iff it's codegen'ed.
   ///
   /// This class lets you emit either a regular diagnostic, a deferred
   /// diagnostic, or no diagnostic at all, according to an argument you pass to
   /// its constructor, thus simplifying the process of creating these "maybe
   /// deferred" diagnostics.
   class DeviceDiagBuilder {
   public:
     enum Kind {
       /// Emit no diagnostics.
       K_Nop,
       /// Emit the diagnostic immediately (i.e., behave like Sema::Diag()).
       K_Immediate,
       /// Emit the diagnostic immediately, and, if it's a warning or error, also
       /// emit a call stack showing how this function can be reached by an a
       /// priori known-emitted function.
       K_ImmediateWithCallStack,
       /// Create a deferred diagnostic, which is emitted only if the function
       /// it's attached to is codegen'ed.  Also emit a call stack as with
       /// K_ImmediateWithCallStack.
       K_Deferred
     };
 
     DeviceDiagBuilder(Kind K, SourceLocation Loc, unsigned DiagID,
                       FunctionDecl *Fn, Sema &S);
     DeviceDiagBuilder(DeviceDiagBuilder &&D);
     DeviceDiagBuilder(const DeviceDiagBuilder &) = default;
     ~DeviceDiagBuilder();
 
     /// Convertible to bool: True if we immediately emitted an error, false if
     /// we didn't emit an error or we created a deferred error.
     ///
     /// Example usage:
     ///
     ///   if (DeviceDiagBuilder(...) << foo << bar)
     ///     return ExprError();
     ///
     /// But see CUDADiagIfDeviceCode() and CUDADiagIfHostCode() -- you probably
     /// want to use these instead of creating a DeviceDiagBuilder yourself.
     operator bool() const { return ImmediateDiag.hasValue(); }
 
     template <typename T>
     friend const DeviceDiagBuilder &operator<<(const DeviceDiagBuilder &Diag,
                                                const T &Value) {
       if (Diag.ImmediateDiag.hasValue())
         *Diag.ImmediateDiag << Value;
       else if (Diag.PartialDiagId.hasValue())
         Diag.S.DeviceDeferredDiags[Diag.Fn][*Diag.PartialDiagId].second
             << Value;
       return Diag;
     }
 
   private:
     Sema &S;
     SourceLocation Loc;
     unsigned DiagID;
     FunctionDecl *Fn;
     bool ShowCallStack;
 
     // Invariant: At most one of these Optionals has a value.
     // FIXME: Switch these to a Variant once that exists.
     llvm::Optional<SemaDiagnosticBuilder> ImmediateDiag;
     llvm::Optional<unsigned> PartialDiagId;
   };
 
   /// Indicate that this function (and thus everything it transtively calls)
   /// will be codegen'ed, and emit any deferred diagnostics on this function and
   /// its (transitive) callees.
   void markKnownEmitted(
       Sema &S, FunctionDecl *OrigCaller, FunctionDecl *OrigCallee,
       SourceLocation OrigLoc,
       const llvm::function_ref<bool(Sema &, FunctionDecl *)> IsKnownEmitted);
 
   /// Creates a DeviceDiagBuilder that emits the diagnostic if the current context
   /// is "used as device code".
   ///
   /// - If CurContext is a __host__ function, does not emit any diagnostics.
   /// - If CurContext is a __device__ or __global__ function, emits the
   ///   diagnostics immediately.
   /// - If CurContext is a __host__ __device__ function and we are compiling for
   ///   the device, creates a diagnostic which is emitted if and when we realize
   ///   that the function will be codegen'ed.
   ///
   /// Example usage:
   ///
   ///  // Variable-length arrays are not allowed in CUDA device code.
   ///  if (CUDADiagIfDeviceCode(Loc, diag::err_cuda_vla) << CurrentCUDATarget())
   ///    return ExprError();
   ///  // Otherwise, continue parsing as normal.
   DeviceDiagBuilder CUDADiagIfDeviceCode(SourceLocation Loc, unsigned DiagID);
 
   /// Creates a DeviceDiagBuilder that emits the diagnostic if the current context
   /// is "used as host code".
   ///
   /// Same as CUDADiagIfDeviceCode, with "host" and "device" switched.
   DeviceDiagBuilder CUDADiagIfHostCode(SourceLocation Loc, unsigned DiagID);
 
   /// Creates a DeviceDiagBuilder that emits the diagnostic if the current
   /// context is "used as device code".
   ///
   /// - If CurContext is a `declare target` function or it is known that the
   /// function is emitted for the device, emits the diagnostics immediately.
   /// - If CurContext is a non-`declare target` function and we are compiling
   ///   for the device, creates a diagnostic which is emitted if and when we
   ///   realize that the function will be codegen'ed.
   ///
   /// Example usage:
   ///
   ///  // Variable-length arrays are not allowed in NVPTX device code.
   ///  if (diagIfOpenMPDeviceCode(Loc, diag::err_vla_unsupported))
   ///    return ExprError();
   ///  // Otherwise, continue parsing as normal.
   DeviceDiagBuilder diagIfOpenMPDeviceCode(SourceLocation Loc, unsigned DiagID);
 
   /// Creates a DeviceDiagBuilder that emits the diagnostic if the current
   /// context is "used as host code".
   ///
   /// - If CurContext is a `declare target` function or it is known that the
   /// function is emitted for the host, emits the diagnostics immediately.
   /// - If CurContext is a non-host function, just ignore it.
   ///
   /// Example usage:
   ///
   ///  // Variable-length arrays are not allowed in NVPTX device code.
   ///  if (diagIfOpenMPHostode(Loc, diag::err_vla_unsupported))
   ///    return ExprError();
   ///  // Otherwise, continue parsing as normal.
   DeviceDiagBuilder diagIfOpenMPHostCode(SourceLocation Loc, unsigned DiagID);
 
   DeviceDiagBuilder targetDiag(SourceLocation Loc, unsigned DiagID);
 
   enum CUDAFunctionTarget {
     CFT_Device,
     CFT_Global,
     CFT_Host,
     CFT_HostDevice,
     CFT_InvalidTarget
   };
 
   /// Determines whether the given function is a CUDA device/host/kernel/etc.
   /// function.
   ///
   /// Use this rather than examining the function's attributes yourself -- you
   /// will get it wrong.  Returns CFT_Host if D is null.
   CUDAFunctionTarget IdentifyCUDATarget(const FunctionDecl *D,
                                         bool IgnoreImplicitHDAttr = false);
   CUDAFunctionTarget IdentifyCUDATarget(const ParsedAttributesView &Attrs);
 
   /// Gets the CUDA target for the current context.
   CUDAFunctionTarget CurrentCUDATarget() {
     return IdentifyCUDATarget(dyn_cast<FunctionDecl>(CurContext));
   }
 
   // CUDA function call preference. Must be ordered numerically from
   // worst to best.
   enum CUDAFunctionPreference {
     CFP_Never,      // Invalid caller/callee combination.
     CFP_WrongSide,  // Calls from host-device to host or device
                     // function that do not match current compilation
                     // mode.
     CFP_HostDevice, // Any calls to host/device functions.
     CFP_SameSide,   // Calls from host-device to host or device
                     // function matching current compilation mode.
     CFP_Native,     // host-to-host or device-to-device calls.
   };
 
   /// Identifies relative preference of a given Caller/Callee
   /// combination, based on their host/device attributes.
   /// \param Caller function which needs address of \p Callee.
   ///               nullptr in case of global context.
   /// \param Callee target function
   ///
   /// \returns preference value for particular Caller/Callee combination.
   CUDAFunctionPreference IdentifyCUDAPreference(const FunctionDecl *Caller,
                                                 const FunctionDecl *Callee);
 
   /// Determines whether Caller may invoke Callee, based on their CUDA
   /// host/device attributes.  Returns false if the call is not allowed.
   ///
   /// Note: Will return true for CFP_WrongSide calls.  These may appear in
   /// semantically correct CUDA programs, but only if they're never codegen'ed.
   bool IsAllowedCUDACall(const FunctionDecl *Caller,
                          const FunctionDecl *Callee) {
     return IdentifyCUDAPreference(Caller, Callee) != CFP_Never;
   }
 
   /// May add implicit CUDAHostAttr and CUDADeviceAttr attributes to FD,
   /// depending on FD and the current compilation settings.
   void maybeAddCUDAHostDeviceAttrs(FunctionDecl *FD,
                                    const LookupResult &Previous);
 
 public:
   /// Check whether we're allowed to call Callee from the current context.
   ///
   /// - If the call is never allowed in a semantically-correct program
   ///   (CFP_Never), emits an error and returns false.
   ///
   /// - If the call is allowed in semantically-correct programs, but only if
   ///   it's never codegen'ed (CFP_WrongSide), creates a deferred diagnostic to
   ///   be emitted if and when the caller is codegen'ed, and returns true.
   ///
   ///   Will only create deferred diagnostics for a given SourceLocation once,
   ///   so you can safely call this multiple times without generating duplicate
   ///   deferred errors.
   ///
   /// - Otherwise, returns true without emitting any diagnostics.
   bool CheckCUDACall(SourceLocation Loc, FunctionDecl *Callee);
 
   /// Set __device__ or __host__ __device__ attributes on the given lambda
   /// operator() method.
   ///
   /// CUDA lambdas declared inside __device__ or __global__ functions inherit
   /// the __device__ attribute.  Similarly, lambdas inside __host__ __device__
   /// functions become __host__ __device__ themselves.
   void CUDASetLambdaAttrs(CXXMethodDecl *Method);
 
   /// Finds a function in \p Matches with highest calling priority
   /// from \p Caller context and erases all functions with lower
   /// calling priority.
   void EraseUnwantedCUDAMatches(
       const FunctionDecl *Caller,
       SmallVectorImpl<std::pair<DeclAccessPair, FunctionDecl *>> &Matches);
 
   /// Given a implicit special member, infer its CUDA target from the
   /// calls it needs to make to underlying base/field special members.
   /// \param ClassDecl the class for which the member is being created.
   /// \param CSM the kind of special member.
   /// \param MemberDecl the special member itself.
   /// \param ConstRHS true if this is a copy operation with a const object on
   ///        its RHS.
   /// \param Diagnose true if this call should emit diagnostics.
   /// \return true if there was an error inferring.
   /// The result of this call is implicit CUDA target attribute(s) attached to
   /// the member declaration.
   bool inferCUDATargetForImplicitSpecialMember(CXXRecordDecl *ClassDecl,
                                                CXXSpecialMember CSM,
                                                CXXMethodDecl *MemberDecl,
                                                bool ConstRHS,
                                                bool Diagnose);
 
   /// \return true if \p CD can be considered empty according to CUDA
   /// (E.2.3.1 in CUDA 7.5 Programming guide).
   bool isEmptyCudaConstructor(SourceLocation Loc, CXXConstructorDecl *CD);
   bool isEmptyCudaDestructor(SourceLocation Loc, CXXDestructorDecl *CD);
 
   // \brief Checks that initializers of \p Var satisfy CUDA restrictions. In
   // case of error emits appropriate diagnostic and invalidates \p Var.
   //
   // \details CUDA allows only empty constructors as initializers for global
   // variables (see E.2.3.1, CUDA 7.5). The same restriction also applies to all
   // __shared__ variables whether they are local or not (they all are implicitly
   // static in CUDA). One exception is that CUDA allows constant initializers
   // for __constant__ and __device__ variables.
   void checkAllowedCUDAInitializer(VarDecl *VD);
 
   /// Check whether NewFD is a valid overload for CUDA. Emits
   /// diagnostics and invalidates NewFD if not.
   void checkCUDATargetOverload(FunctionDecl *NewFD,
                                const LookupResult &Previous);
   /// Copies target attributes from the template TD to the function FD.
   void inheritCUDATargetAttrs(FunctionDecl *FD, const FunctionTemplateDecl &TD);
 
   /// Returns the name of the launch configuration function.  This is the name
   /// of the function that will be called to configure kernel call, with the
   /// parameters specified via <<<>>>.
   std::string getCudaConfigureFuncName() const;
 
   /// \name Code completion
   //@{
   /// Describes the context in which code completion occurs.
   enum ParserCompletionContext {
     /// Code completion occurs at top-level or namespace context.
     PCC_Namespace,
     /// Code completion occurs within a class, struct, or union.
     PCC_Class,
     /// Code completion occurs within an Objective-C interface, protocol,
     /// or category.
     PCC_ObjCInterface,
     /// Code completion occurs within an Objective-C implementation or
     /// category implementation
     PCC_ObjCImplementation,
     /// Code completion occurs within the list of instance variables
     /// in an Objective-C interface, protocol, category, or implementation.
     PCC_ObjCInstanceVariableList,
     /// Code completion occurs following one or more template
     /// headers.
     PCC_Template,
     /// Code completion occurs following one or more template
     /// headers within a class.
     PCC_MemberTemplate,
     /// Code completion occurs within an expression.
     PCC_Expression,
     /// Code completion occurs within a statement, which may
     /// also be an expression or a declaration.
     PCC_Statement,
     /// Code completion occurs at the beginning of the
     /// initialization statement (or expression) in a for loop.
     PCC_ForInit,
     /// Code completion occurs within the condition of an if,
     /// while, switch, or for statement.
     PCC_Condition,
     /// Code completion occurs within the body of a function on a
     /// recovery path, where we do not have a specific handle on our position
     /// in the grammar.
     PCC_RecoveryInFunction,
     /// Code completion occurs where only a type is permitted.
     PCC_Type,
     /// Code completion occurs in a parenthesized expression, which
     /// might also be a type cast.
     PCC_ParenthesizedExpression,
     /// Code completion occurs within a sequence of declaration
     /// specifiers within a function, method, or block.
     PCC_LocalDeclarationSpecifiers
   };
 
   void CodeCompleteModuleImport(SourceLocation ImportLoc, ModuleIdPath Path);
   void CodeCompleteOrdinaryName(Scope *S,
                                 ParserCompletionContext CompletionContext);
   void CodeCompleteDeclSpec(Scope *S, DeclSpec &DS,
                             bool AllowNonIdentifiers,
                             bool AllowNestedNameSpecifiers);
 
   struct CodeCompleteExpressionData;
   void CodeCompleteExpression(Scope *S,
                               const CodeCompleteExpressionData &Data);
   void CodeCompleteExpression(Scope *S, QualType PreferredType,
                               bool IsParenthesized = false);
   void CodeCompleteMemberReferenceExpr(Scope *S, Expr *Base, Expr *OtherOpBase,
                                        SourceLocation OpLoc, bool IsArrow,
                                        bool IsBaseExprStatement,
                                        QualType PreferredType);
   void CodeCompletePostfixExpression(Scope *S, ExprResult LHS,
                                      QualType PreferredType);
   void CodeCompleteTag(Scope *S, unsigned TagSpec);
   void CodeCompleteTypeQualifiers(DeclSpec &DS);
   void CodeCompleteFunctionQualifiers(DeclSpec &DS, Declarator &D,
                                       const VirtSpecifiers *VS = nullptr);
   void CodeCompleteBracketDeclarator(Scope *S);
   void CodeCompleteCase(Scope *S);
   /// Reports signatures for a call to CodeCompleteConsumer and returns the
   /// preferred type for the current argument. Returned type can be null.
   QualType ProduceCallSignatureHelp(Scope *S, Expr *Fn, ArrayRef<Expr *> Args,
                                     SourceLocation OpenParLoc);
   QualType ProduceConstructorSignatureHelp(Scope *S, QualType Type,
                                            SourceLocation Loc,
                                            ArrayRef<Expr *> Args,
                                            SourceLocation OpenParLoc);
   QualType ProduceCtorInitMemberSignatureHelp(Scope *S, Decl *ConstructorDecl,
                                               CXXScopeSpec SS,
                                               ParsedType TemplateTypeTy,
                                               ArrayRef<Expr *> ArgExprs,
                                               IdentifierInfo *II,
                                               SourceLocation OpenParLoc);
   void CodeCompleteInitializer(Scope *S, Decl *D);
   /// Trigger code completion for a record of \p BaseType. \p InitExprs are
   /// expressions in the initializer list seen so far and \p D is the current
   /// Designation being parsed.
   void CodeCompleteDesignator(const QualType BaseType,
                               llvm::ArrayRef<Expr *> InitExprs,
                               const Designation &D);
   void CodeCompleteAfterIf(Scope *S);
 
   void CodeCompleteQualifiedId(Scope *S, CXXScopeSpec &SS, bool EnteringContext,
                                bool IsUsingDeclaration, QualType BaseType,
                                QualType PreferredType);
   void CodeCompleteUsing(Scope *S);
   void CodeCompleteUsingDirective(Scope *S);
   void CodeCompleteNamespaceDecl(Scope *S);
   void CodeCompleteNamespaceAliasDecl(Scope *S);
   void CodeCompleteOperatorName(Scope *S);
   void CodeCompleteConstructorInitializer(
                                 Decl *Constructor,
                                 ArrayRef<CXXCtorInitializer *> Initializers);
 
   void CodeCompleteLambdaIntroducer(Scope *S, LambdaIntroducer &Intro,
                                     bool AfterAmpersand);
 
   void CodeCompleteObjCAtDirective(Scope *S);
   void CodeCompleteObjCAtVisibility(Scope *S);
   void CodeCompleteObjCAtStatement(Scope *S);
   void CodeCompleteObjCAtExpression(Scope *S);
   void CodeCompleteObjCPropertyFlags(Scope *S, ObjCDeclSpec &ODS);
   void CodeCompleteObjCPropertyGetter(Scope *S);
   void CodeCompleteObjCPropertySetter(Scope *S);
   void CodeCompleteObjCPassingType(Scope *S, ObjCDeclSpec &DS,
                                    bool IsParameter);
   void CodeCompleteObjCMessageReceiver(Scope *S);
   void CodeCompleteObjCSuperMessage(Scope *S, SourceLocation SuperLoc,
                                     ArrayRef<IdentifierInfo *> SelIdents,
                                     bool AtArgumentExpression);
   void CodeCompleteObjCClassMessage(Scope *S, ParsedType Receiver,
                                     ArrayRef<IdentifierInfo *> SelIdents,
                                     bool AtArgumentExpression,
                                     bool IsSuper = false);
   void CodeCompleteObjCInstanceMessage(Scope *S, Expr *Receiver,
                                        ArrayRef<IdentifierInfo *> SelIdents,
                                        bool AtArgumentExpression,
                                        ObjCInterfaceDecl *Super = nullptr);
   void CodeCompleteObjCForCollection(Scope *S,
                                      DeclGroupPtrTy IterationVar);
   void CodeCompleteObjCSelector(Scope *S,
                                 ArrayRef<IdentifierInfo *> SelIdents);
   void CodeCompleteObjCProtocolReferences(
                                          ArrayRef<IdentifierLocPair> Protocols);
   void CodeCompleteObjCProtocolDecl(Scope *S);
   void CodeCompleteObjCInterfaceDecl(Scope *S);
   void CodeCompleteObjCSuperclass(Scope *S,
                                   IdentifierInfo *ClassName,
                                   SourceLocation ClassNameLoc);
   void CodeCompleteObjCImplementationDecl(Scope *S);
   void CodeCompleteObjCInterfaceCategory(Scope *S,
                                          IdentifierInfo *ClassName,
                                          SourceLocation ClassNameLoc);
   void CodeCompleteObjCImplementationCategory(Scope *S,
                                               IdentifierInfo *ClassName,
                                               SourceLocation ClassNameLoc);
   void CodeCompleteObjCPropertyDefinition(Scope *S);
   void CodeCompleteObjCPropertySynthesizeIvar(Scope *S,
                                               IdentifierInfo *PropertyName);
   void CodeCompleteObjCMethodDecl(Scope *S, Optional<bool> IsInstanceMethod,
                                   ParsedType ReturnType);
   void CodeCompleteObjCMethodDeclSelector(Scope *S,
                                           bool IsInstanceMethod,
                                           bool AtParameterName,
                                           ParsedType ReturnType,
                                           ArrayRef<IdentifierInfo *> SelIdents);
   void CodeCompleteObjCClassPropertyRefExpr(Scope *S, IdentifierInfo &ClassName,
                                             SourceLocation ClassNameLoc,
                                             bool IsBaseExprStatement);
   void CodeCompletePreprocessorDirective(bool InConditional);
   void CodeCompleteInPreprocessorConditionalExclusion(Scope *S);
   void CodeCompletePreprocessorMacroName(bool IsDefinition);
   void CodeCompletePreprocessorExpression();
   void CodeCompletePreprocessorMacroArgument(Scope *S,
                                              IdentifierInfo *Macro,
                                              MacroInfo *MacroInfo,
                                              unsigned Argument);
   void CodeCompleteIncludedFile(llvm::StringRef Dir, bool IsAngled);
   void CodeCompleteNaturalLanguage();
   void CodeCompleteAvailabilityPlatformName();
   void GatherGlobalCodeCompletions(CodeCompletionAllocator &Allocator,
                                    CodeCompletionTUInfo &CCTUInfo,
                   SmallVectorImpl<CodeCompletionResult> &Results);
   //@}
 
   //===--------------------------------------------------------------------===//
   // Extra semantic analysis beyond the C type system
 
 public:
   SourceLocation getLocationOfStringLiteralByte(const StringLiteral *SL,
                                                 unsigned ByteNo) const;
 
 private:
   void CheckArrayAccess(const Expr *BaseExpr, const Expr *IndexExpr,
                         const ArraySubscriptExpr *ASE=nullptr,
                         bool AllowOnePastEnd=true, bool IndexNegated=false);
   void CheckArrayAccess(const Expr *E);
   // Used to grab the relevant information from a FormatAttr and a
   // FunctionDeclaration.
   struct FormatStringInfo {
     unsigned FormatIdx;
     unsigned FirstDataArg;
     bool HasVAListArg;
   };
 
   static bool getFormatStringInfo(const FormatAttr *Format, bool IsCXXMember,
                                   FormatStringInfo *FSI);
   bool CheckFunctionCall(FunctionDecl *FDecl, CallExpr *TheCall,
                          const FunctionProtoType *Proto);
   bool CheckObjCMethodCall(ObjCMethodDecl *Method, SourceLocation loc,
                            ArrayRef<const Expr *> Args);
   bool CheckPointerCall(NamedDecl *NDecl, CallExpr *TheCall,
                         const FunctionProtoType *Proto);
   bool CheckOtherCall(CallExpr *TheCall, const FunctionProtoType *Proto);
   void CheckConstructorCall(FunctionDecl *FDecl,
                             ArrayRef<const Expr *> Args,
                             const FunctionProtoType *Proto,
                             SourceLocation Loc);
 
   void checkCall(NamedDecl *FDecl, const FunctionProtoType *Proto,
                  const Expr *ThisArg, ArrayRef<const Expr *> Args,
                  bool IsMemberFunction, SourceLocation Loc, SourceRange Range,
                  VariadicCallType CallType);
 
   bool CheckObjCString(Expr *Arg);
   ExprResult CheckOSLogFormatStringArg(Expr *Arg);
 
   ExprResult CheckBuiltinFunctionCall(FunctionDecl *FDecl,
                                       unsigned BuiltinID, CallExpr *TheCall);
   void checkFortifiedBuiltinMemoryFunction(FunctionDecl *FD, CallExpr *TheCall);
 
   bool CheckARMBuiltinExclusiveCall(unsigned BuiltinID, CallExpr *TheCall,
                                     unsigned MaxWidth);
   bool CheckNeonBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckMVEBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckCDEBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckARMCoprocessorImmediate(const Expr *CoprocArg, bool WantCDE);
   bool CheckARMBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
 
   bool CheckAArch64BuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckBPFBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckHexagonBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckHexagonBuiltinArgument(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckMipsBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckMipsBuiltinCpu(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckMipsBuiltinArgument(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckSystemZBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckX86BuiltinRoundingOrSAE(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckX86BuiltinGatherScatterScale(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckX86BuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
   bool CheckPPCBuiltinFunctionCall(unsigned BuiltinID, CallExpr *TheCall);
 
   bool SemaBuiltinVAStart(unsigned BuiltinID, CallExpr *TheCall);
   bool SemaBuiltinVAStartARMMicrosoft(CallExpr *Call);
   bool SemaBuiltinUnorderedCompare(CallExpr *TheCall);
   bool SemaBuiltinFPClassification(CallExpr *TheCall, unsigned NumArgs);
   bool SemaBuiltinVSX(CallExpr *TheCall);
   bool SemaBuiltinOSLogFormat(CallExpr *TheCall);
 
 public:
   // Used by C++ template instantiation.
   ExprResult SemaBuiltinShuffleVector(CallExpr *TheCall);
   ExprResult SemaConvertVectorExpr(Expr *E, TypeSourceInfo *TInfo,
                                    SourceLocation BuiltinLoc,
                                    SourceLocation RParenLoc);
 
 private:
   bool SemaBuiltinPrefetch(CallExpr *TheCall);
   bool SemaBuiltinAllocaWithAlign(CallExpr *TheCall);
   bool SemaBuiltinAssume(CallExpr *TheCall);
   bool SemaBuiltinAssumeAligned(CallExpr *TheCall);
   bool SemaBuiltinLongjmp(CallExpr *TheCall);
   bool SemaBuiltinSetjmp(CallExpr *TheCall);
   ExprResult SemaBuiltinAtomicOverloaded(ExprResult TheCallResult);
   ExprResult SemaBuiltinNontemporalOverloaded(ExprResult TheCallResult);
   ExprResult SemaAtomicOpsOverloaded(ExprResult TheCallResult,
                                      AtomicExpr::AtomicOp Op);
   ExprResult SemaBuiltinOperatorNewDeleteOverloaded(ExprResult TheCallResult,
                                                     bool IsDelete);
   bool SemaBuiltinConstantArg(CallExpr *TheCall, int ArgNum,
                               llvm::APSInt &Result);
   bool SemaBuiltinConstantArgRange(CallExpr *TheCall, int ArgNum, int Low,
                                    int High, bool RangeIsError = true);
   bool SemaBuiltinConstantArgMultiple(CallExpr *TheCall, int ArgNum,
                                       unsigned Multiple);
   bool SemaBuiltinConstantArgPower2(CallExpr *TheCall, int ArgNum);
   bool SemaBuiltinConstantArgShiftedByte(CallExpr *TheCall, int ArgNum,
                                          unsigned ArgBits);
   bool SemaBuiltinConstantArgShiftedByteOrXXFF(CallExpr *TheCall, int ArgNum,
                                                unsigned ArgBits);
   bool SemaBuiltinARMSpecialReg(unsigned BuiltinID, CallExpr *TheCall,
                                 int ArgNum, unsigned ExpectedFieldNum,
                                 bool AllowName);
   bool SemaBuiltinARMMemoryTaggingCall(unsigned BuiltinID, CallExpr *TheCall);
 public:
   enum FormatStringType {
     FST_Scanf,
     FST_Printf,
     FST_NSString,
     FST_Strftime,
     FST_Strfmon,
     FST_Kprintf,
     FST_FreeBSDKPrintf,
     FST_OSTrace,
     FST_OSLog,
     FST_Unknown
   };
   static FormatStringType GetFormatStringType(const FormatAttr *Format);
 
   bool FormatStringHasSArg(const StringLiteral *FExpr);
 
   static bool GetFormatNSStringIdx(const FormatAttr *Format, unsigned &Idx);
 
 private:
   bool CheckFormatArguments(const FormatAttr *Format,
                             ArrayRef<const Expr *> Args,
                             bool IsCXXMember,
                             VariadicCallType CallType,
                             SourceLocation Loc, SourceRange Range,
                             llvm::SmallBitVector &CheckedVarArgs);
   bool CheckFormatArguments(ArrayRef<const Expr *> Args,
                             bool HasVAListArg, unsigned format_idx,
                             unsigned firstDataArg, FormatStringType Type,
                             VariadicCallType CallType,
                             SourceLocation Loc, SourceRange range,
                             llvm::SmallBitVector &CheckedVarArgs);
 
   void CheckAbsoluteValueFunction(const CallExpr *Call,
                                   const FunctionDecl *FDecl);
 
   void CheckMaxUnsignedZero(const CallExpr *Call, const FunctionDecl *FDecl);
 
   void CheckMemaccessArguments(const CallExpr *Call,
                                unsigned BId,
                                IdentifierInfo *FnName);
 
   void CheckStrlcpycatArguments(const CallExpr *Call,
                                 IdentifierInfo *FnName);
 
   void CheckStrncatArguments(const CallExpr *Call,
                              IdentifierInfo *FnName);
 
   void CheckReturnValExpr(Expr *RetValExp, QualType lhsType,
                           SourceLocation ReturnLoc,
                           bool isObjCMethod = false,
                           const AttrVec *Attrs = nullptr,
                           const FunctionDecl *FD = nullptr);
 
 public:
   void CheckFloatComparison(SourceLocation Loc, Expr *LHS, Expr *RHS);
 
 private:
   void CheckImplicitConversions(Expr *E, SourceLocation CC = SourceLocation());
   void CheckBoolLikeConversion(Expr *E, SourceLocation CC);
   void CheckForIntOverflow(Expr *E);
   void CheckUnsequencedOperations(const Expr *E);
 
   /// Perform semantic checks on a completed expression. This will either
   /// be a full-expression or a default argument expression.
   void CheckCompletedExpr(Expr *E, SourceLocation CheckLoc = SourceLocation(),
                           bool IsConstexpr = false);
 
   void CheckBitFieldInitialization(SourceLocation InitLoc, FieldDecl *Field,
                                    Expr *Init);
 
   /// Check if there is a field shadowing.
   void CheckShadowInheritedFields(const SourceLocation &Loc,
                                   DeclarationName FieldName,
                                   const CXXRecordDecl *RD,
                                   bool DeclIsField = true);
 
   /// Check if the given expression contains 'break' or 'continue'
   /// statement that produces control flow different from GCC.
   void CheckBreakContinueBinding(Expr *E);
 
   /// Check whether receiver is mutable ObjC container which
   /// attempts to add itself into the container
   void CheckObjCCircularContainer(ObjCMessageExpr *Message);
 
   void AnalyzeDeleteExprMismatch(const CXXDeleteExpr *DE);
   void AnalyzeDeleteExprMismatch(FieldDecl *Field, SourceLocation DeleteLoc,
                                  bool DeleteWasArrayForm);
 public:
   /// Register a magic integral constant to be used as a type tag.
   void RegisterTypeTagForDatatype(const IdentifierInfo *ArgumentKind,
                                   uint64_t MagicValue, QualType Type,
                                   bool LayoutCompatible, bool MustBeNull);
 
   struct TypeTagData {
     TypeTagData() {}
 
     TypeTagData(QualType Type, bool LayoutCompatible, bool MustBeNull) :
         Type(Type), LayoutCompatible(LayoutCompatible),
         MustBeNull(MustBeNull)
     {}
 
     QualType Type;
 
     /// If true, \c Type should be compared with other expression's types for
     /// layout-compatibility.
     unsigned LayoutCompatible : 1;
     unsigned MustBeNull : 1;
   };
 
   /// A pair of ArgumentKind identifier and magic value.  This uniquely
   /// identifies the magic value.
   typedef std::pair<const IdentifierInfo *, uint64_t> TypeTagMagicValue;
 
 private:
   /// A map from magic value to type information.
   std::unique_ptr<llvm::DenseMap<TypeTagMagicValue, TypeTagData>>
       TypeTagForDatatypeMagicValues;
 
   /// Peform checks on a call of a function with argument_with_type_tag
   /// or pointer_with_type_tag attributes.
   void CheckArgumentWithTypeTag(const ArgumentWithTypeTagAttr *Attr,
                                 const ArrayRef<const Expr *> ExprArgs,
                                 SourceLocation CallSiteLoc);
 
   /// Check if we are taking the address of a packed field
   /// as this may be a problem if the pointer value is dereferenced.
   void CheckAddressOfPackedMember(Expr *rhs);
 
   /// The parser's current scope.
   ///
   /// The parser maintains this state here.
   Scope *CurScope;
 
   mutable IdentifierInfo *Ident_super;
   mutable IdentifierInfo *Ident___float128;
 
   /// Nullability type specifiers.
   IdentifierInfo *Ident__Nonnull = nullptr;
   IdentifierInfo *Ident__Nullable = nullptr;
   IdentifierInfo *Ident__Null_unspecified = nullptr;
 
   IdentifierInfo *Ident_NSError = nullptr;
 
   /// The handler for the FileChanged preprocessor events.
   ///
   /// Used for diagnostics that implement custom semantic analysis for #include
   /// directives, like -Wpragma-pack.
   sema::SemaPPCallbacks *SemaPPCallbackHandler;
 
 protected:
   friend class Parser;
   friend class InitializationSequence;
   friend class ASTReader;
   friend class ASTDeclReader;
   friend class ASTWriter;
 
 public:
   /// Retrieve the keyword associated
   IdentifierInfo *getNullabilityKeyword(NullabilityKind nullability);
 
   /// The struct behind the CFErrorRef pointer.
   RecordDecl *CFError = nullptr;
 
   /// Retrieve the identifier "NSError".
   IdentifierInfo *getNSErrorIdent();
 
   /// Retrieve the parser's current scope.
   ///
   /// This routine must only be used when it is certain that semantic analysis
   /// and the parser are in precisely the same context, which is not the case
   /// when, e.g., we are performing any kind of template instantiation.
   /// Therefore, the only safe places to use this scope are in the parser
   /// itself and in routines directly invoked from the parser and *never* from
   /// template substitution or instantiation.
   Scope *getCurScope() const { return CurScope; }
 
   void incrementMSManglingNumber() const {
     return CurScope->incrementMSManglingNumber();
   }
 
   IdentifierInfo *getSuperIdentifier() const;
   IdentifierInfo *getFloat128Identifier() const;
 
   Decl *getObjCDeclContext() const;
 
   DeclContext *getCurLexicalContext() const {
     return OriginalLexicalContext ? OriginalLexicalContext : CurContext;
   }
 
   const DeclContext *getCurObjCLexicalContext() const {
     const DeclContext *DC = getCurLexicalContext();
     // A category implicitly has the attribute of the interface.
     if (const ObjCCategoryDecl *CatD = dyn_cast<ObjCCategoryDecl>(DC))
       DC = CatD->getClassInterface();
     return DC;
   }
 
   /// Determine the number of levels of enclosing template parameters. This is
   /// only usable while parsing. Note that this does not include dependent
   /// contexts in which no template parameters have yet been declared, such as
   /// in a terse function template or generic lambda before the first 'auto' is
   /// encountered.
   unsigned getTemplateDepth(Scope *S) const;
 
   /// To be used for checking whether the arguments being passed to
   /// function exceeds the number of parameters expected for it.
   static bool TooManyArguments(size_t NumParams, size_t NumArgs,
                                bool PartialOverloading = false) {
     // We check whether we're just after a comma in code-completion.
     if (NumArgs > 0 && PartialOverloading)
       return NumArgs + 1 > NumParams; // If so, we view as an extra argument.
     return NumArgs > NumParams;
   }
 
   // Emitting members of dllexported classes is delayed until the class
   // (including field initializers) is fully parsed.
   SmallVector<CXXRecordDecl*, 4> DelayedDllExportClasses;
   SmallVector<CXXMethodDecl*, 4> DelayedDllExportMemberFunctions;
 
 private:
   int ParsingClassDepth = 0;
 
   class SavePendingParsedClassStateRAII {
   public:
     SavePendingParsedClassStateRAII(Sema &S) : S(S) { swapSavedState(); }
 
     ~SavePendingParsedClassStateRAII() {
       assert(S.DelayedOverridingExceptionSpecChecks.empty() &&
              "there shouldn't be any pending delayed exception spec checks");
       assert(S.DelayedEquivalentExceptionSpecChecks.empty() &&
              "there shouldn't be any pending delayed exception spec checks");
       swapSavedState();
     }
 
   private:
     Sema &S;
     decltype(DelayedOverridingExceptionSpecChecks)
         SavedOverridingExceptionSpecChecks;
     decltype(DelayedEquivalentExceptionSpecChecks)
         SavedEquivalentExceptionSpecChecks;
 
     void swapSavedState() {
       SavedOverridingExceptionSpecChecks.swap(
           S.DelayedOverridingExceptionSpecChecks);
       SavedEquivalentExceptionSpecChecks.swap(
           S.DelayedEquivalentExceptionSpecChecks);
     }
   };
 
   /// Helper class that collects misaligned member designations and
   /// their location info for delayed diagnostics.
   struct MisalignedMember {
     Expr *E;
     RecordDecl *RD;
     ValueDecl *MD;
     CharUnits Alignment;
 
     MisalignedMember() : E(), RD(), MD(), Alignment() {}
     MisalignedMember(Expr *E, RecordDecl *RD, ValueDecl *MD,
                      CharUnits Alignment)
         : E(E), RD(RD), MD(MD), Alignment(Alignment) {}
     explicit MisalignedMember(Expr *E)
         : MisalignedMember(E, nullptr, nullptr, CharUnits()) {}
 
     bool operator==(const MisalignedMember &m) { return this->E == m.E; }
   };
   /// Small set of gathered accesses to potentially misaligned members
   /// due to the packed attribute.
   SmallVector<MisalignedMember, 4> MisalignedMembers;
 
   /// Adds an expression to the set of gathered misaligned members.
   void AddPotentialMisalignedMembers(Expr *E, RecordDecl *RD, ValueDecl *MD,
                                      CharUnits Alignment);
 
 public:
   /// Diagnoses the current set of gathered accesses. This typically
   /// happens at full expression level. The set is cleared after emitting the
   /// diagnostics.
   void DiagnoseMisalignedMembers();
 
   /// This function checks if the expression is in the sef of potentially
   /// misaligned members and it is converted to some pointer type T with lower
   /// or equal alignment requirements. If so it removes it. This is used when
   /// we do not want to diagnose such misaligned access (e.g. in conversions to
   /// void*).
   void DiscardMisalignedMemberAddress(const Type *T, Expr *E);
 
   /// This function calls Action when it determines that E designates a
   /// misaligned member due to the packed attribute. This is used to emit
   /// local diagnostics like in reference binding.
   void RefersToMemberWithReducedAlignment(
       Expr *E,
       llvm::function_ref<void(Expr *, RecordDecl *, FieldDecl *, CharUnits)>
           Action);
 
   /// Describes the reason a calling convention specification was ignored, used
   /// for diagnostics.
   enum class CallingConventionIgnoredReason {
     ForThisTarget = 0,
     VariadicFunction,
     ConstructorDestructor,
     BuiltinFunction
   };
 };
 
 /// RAII object that enters a new expression evaluation context.
 class EnterExpressionEvaluationContext {
   Sema &Actions;
   bool Entered = true;
 
 public:
   EnterExpressionEvaluationContext(
       Sema &Actions, Sema::ExpressionEvaluationContext NewContext,
       Decl *LambdaContextDecl = nullptr,
       Sema::ExpressionEvaluationContextRecord::ExpressionKind ExprContext =
           Sema::ExpressionEvaluationContextRecord::EK_Other,
       bool ShouldEnter = true)
       : Actions(Actions), Entered(ShouldEnter) {
     if (Entered)
       Actions.PushExpressionEvaluationContext(NewContext, LambdaContextDecl,
                                               ExprContext);
   }
   EnterExpressionEvaluationContext(
       Sema &Actions, Sema::ExpressionEvaluationContext NewContext,
       Sema::ReuseLambdaContextDecl_t,
       Sema::ExpressionEvaluationContextRecord::ExpressionKind ExprContext =
           Sema::ExpressionEvaluationContextRecord::EK_Other)
       : Actions(Actions) {
     Actions.PushExpressionEvaluationContext(
         NewContext, Sema::ReuseLambdaContextDecl, ExprContext);
   }
 
   enum InitListTag { InitList };
   EnterExpressionEvaluationContext(Sema &Actions, InitListTag,
                                    bool ShouldEnter = true)
       : Actions(Actions), Entered(false) {
     // In C++11 onwards, narrowing checks are performed on the contents of
     // braced-init-lists, even when they occur within unevaluated operands.
     // Therefore we still need to instantiate constexpr functions used in such
     // a context.
     if (ShouldEnter && Actions.isUnevaluatedContext() &&
         Actions.getLangOpts().CPlusPlus11) {
       Actions.PushExpressionEvaluationContext(
           Sema::ExpressionEvaluationContext::UnevaluatedList);
       Entered = true;
     }
   }
 
   ~EnterExpressionEvaluationContext() {
     if (Entered)
       Actions.PopExpressionEvaluationContext();
   }
 };
 
 DeductionFailureInfo
 MakeDeductionFailureInfo(ASTContext &Context, Sema::TemplateDeductionResult TDK,
                          sema::TemplateDeductionInfo &Info);
 
 /// Contains a late templated function.
 /// Will be parsed at the end of the translation unit, used by Sema & Parser.
 struct LateParsedTemplate {
   CachedTokens Toks;
   /// The template function declaration to be late parsed.
   Decl *D;
 };
 } // end namespace clang
 
 namespace llvm {
 // Hash a FunctionDeclAndLoc by looking at both its FunctionDecl and its
 // SourceLocation.
 template <> struct DenseMapInfo<clang::Sema::FunctionDeclAndLoc> {
   using FunctionDeclAndLoc = clang::Sema::FunctionDeclAndLoc;
   using FDBaseInfo = DenseMapInfo<clang::CanonicalDeclPtr<clang::FunctionDecl>>;
 
   static FunctionDeclAndLoc getEmptyKey() {
     return {FDBaseInfo::getEmptyKey(), clang::SourceLocation()};
   }
 
   static FunctionDeclAndLoc getTombstoneKey() {
     return {FDBaseInfo::getTombstoneKey(), clang::SourceLocation()};
   }
 
   static unsigned getHashValue(const FunctionDeclAndLoc &FDL) {
     return hash_combine(FDBaseInfo::getHashValue(FDL.FD),
                         FDL.Loc.getRawEncoding());
   }
 
   static bool isEqual(const FunctionDeclAndLoc &LHS,
                       const FunctionDeclAndLoc &RHS) {
     return LHS.FD == RHS.FD && LHS.Loc == RHS.Loc;
   }
 };
 } // namespace llvm
 
 #endif
diff --git a/clang/lib/AST/OpenMPClause.cpp b/clang/lib/AST/OpenMPClause.cpp
index b01aae433763..a95789067056 100644
--- a/clang/lib/AST/OpenMPClause.cpp
+++ b/clang/lib/AST/OpenMPClause.cpp
@@ -1,1905 +1,1910 @@
 //===- OpenMPClause.cpp - Classes for OpenMP clauses ----------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 // This file implements the subclesses of Stmt class declared in OpenMPClause.h
 //
 //===----------------------------------------------------------------------===//
 
 #include "clang/AST/OpenMPClause.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/Attr.h"
 #include "clang/AST/Decl.h"
 #include "clang/AST/DeclOpenMP.h"
 #include "clang/Basic/LLVM.h"
 #include "clang/Basic/OpenMPKinds.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/ErrorHandling.h"
 #include <algorithm>
 #include <cassert>
 
 using namespace clang;
 
 OMPClause::child_range OMPClause::children() {
   switch (getClauseKind()) {
   default:
     break;
 #define OPENMP_CLAUSE(Name, Class)                                             \
   case OMPC_##Name:                                                            \
     return static_cast<Class *>(this)->children();
 #include "clang/Basic/OpenMPKinds.def"
   }
   llvm_unreachable("unknown OMPClause");
 }
 
 OMPClause::child_range OMPClause::used_children() {
   switch (getClauseKind()) {
 #define OPENMP_CLAUSE(Name, Class)                                             \
   case OMPC_##Name:                                                            \
     return static_cast<Class *>(this)->used_children();
 #include "clang/Basic/OpenMPKinds.def"
   case OMPC_threadprivate:
   case OMPC_uniform:
   case OMPC_device_type:
   case OMPC_match:
   case OMPC_unknown:
     break;
   }
   llvm_unreachable("unknown OMPClause");
 }
 
 OMPClauseWithPreInit *OMPClauseWithPreInit::get(OMPClause *C) {
   auto *Res = OMPClauseWithPreInit::get(const_cast<const OMPClause *>(C));
   return Res ? const_cast<OMPClauseWithPreInit *>(Res) : nullptr;
 }
 
 const OMPClauseWithPreInit *OMPClauseWithPreInit::get(const OMPClause *C) {
   switch (C->getClauseKind()) {
   case OMPC_schedule:
     return static_cast<const OMPScheduleClause *>(C);
   case OMPC_dist_schedule:
     return static_cast<const OMPDistScheduleClause *>(C);
   case OMPC_firstprivate:
     return static_cast<const OMPFirstprivateClause *>(C);
   case OMPC_lastprivate:
     return static_cast<const OMPLastprivateClause *>(C);
   case OMPC_reduction:
     return static_cast<const OMPReductionClause *>(C);
   case OMPC_task_reduction:
     return static_cast<const OMPTaskReductionClause *>(C);
   case OMPC_in_reduction:
     return static_cast<const OMPInReductionClause *>(C);
   case OMPC_linear:
     return static_cast<const OMPLinearClause *>(C);
   case OMPC_if:
     return static_cast<const OMPIfClause *>(C);
   case OMPC_num_threads:
     return static_cast<const OMPNumThreadsClause *>(C);
   case OMPC_num_teams:
     return static_cast<const OMPNumTeamsClause *>(C);
   case OMPC_thread_limit:
     return static_cast<const OMPThreadLimitClause *>(C);
   case OMPC_device:
     return static_cast<const OMPDeviceClause *>(C);
   case OMPC_grainsize:
     return static_cast<const OMPGrainsizeClause *>(C);
   case OMPC_num_tasks:
     return static_cast<const OMPNumTasksClause *>(C);
   case OMPC_final:
     return static_cast<const OMPFinalClause *>(C);
   case OMPC_priority:
     return static_cast<const OMPPriorityClause *>(C);
   case OMPC_default:
   case OMPC_proc_bind:
   case OMPC_safelen:
   case OMPC_simdlen:
   case OMPC_allocator:
   case OMPC_allocate:
   case OMPC_collapse:
   case OMPC_private:
   case OMPC_shared:
   case OMPC_aligned:
   case OMPC_copyin:
   case OMPC_copyprivate:
   case OMPC_ordered:
   case OMPC_nowait:
   case OMPC_untied:
   case OMPC_mergeable:
   case OMPC_threadprivate:
   case OMPC_flush:
   case OMPC_depobj:
   case OMPC_read:
   case OMPC_write:
   case OMPC_update:
   case OMPC_capture:
   case OMPC_seq_cst:
   case OMPC_acq_rel:
   case OMPC_acquire:
   case OMPC_release:
   case OMPC_relaxed:
   case OMPC_depend:
   case OMPC_threads:
   case OMPC_simd:
   case OMPC_map:
   case OMPC_nogroup:
   case OMPC_hint:
   case OMPC_defaultmap:
   case OMPC_unknown:
   case OMPC_uniform:
   case OMPC_to:
   case OMPC_from:
   case OMPC_use_device_ptr:
   case OMPC_is_device_ptr:
   case OMPC_unified_address:
   case OMPC_unified_shared_memory:
   case OMPC_reverse_offload:
   case OMPC_dynamic_allocators:
   case OMPC_atomic_default_mem_order:
   case OMPC_device_type:
   case OMPC_match:
   case OMPC_nontemporal:
   case OMPC_order:
   case OMPC_destroy:
   case OMPC_detach:
     break;
   }
 
   return nullptr;
 }
 
 OMPClauseWithPostUpdate *OMPClauseWithPostUpdate::get(OMPClause *C) {
   auto *Res = OMPClauseWithPostUpdate::get(const_cast<const OMPClause *>(C));
   return Res ? const_cast<OMPClauseWithPostUpdate *>(Res) : nullptr;
 }
 
 const OMPClauseWithPostUpdate *OMPClauseWithPostUpdate::get(const OMPClause *C) {
   switch (C->getClauseKind()) {
   case OMPC_lastprivate:
     return static_cast<const OMPLastprivateClause *>(C);
   case OMPC_reduction:
     return static_cast<const OMPReductionClause *>(C);
   case OMPC_task_reduction:
     return static_cast<const OMPTaskReductionClause *>(C);
   case OMPC_in_reduction:
     return static_cast<const OMPInReductionClause *>(C);
   case OMPC_linear:
     return static_cast<const OMPLinearClause *>(C);
   case OMPC_schedule:
   case OMPC_dist_schedule:
   case OMPC_firstprivate:
   case OMPC_default:
   case OMPC_proc_bind:
   case OMPC_if:
   case OMPC_final:
   case OMPC_num_threads:
   case OMPC_safelen:
   case OMPC_simdlen:
   case OMPC_allocator:
   case OMPC_allocate:
   case OMPC_collapse:
   case OMPC_private:
   case OMPC_shared:
   case OMPC_aligned:
   case OMPC_copyin:
   case OMPC_copyprivate:
   case OMPC_ordered:
   case OMPC_nowait:
   case OMPC_untied:
   case OMPC_mergeable:
   case OMPC_threadprivate:
   case OMPC_flush:
   case OMPC_depobj:
   case OMPC_read:
   case OMPC_write:
   case OMPC_update:
   case OMPC_capture:
   case OMPC_seq_cst:
   case OMPC_acq_rel:
   case OMPC_acquire:
   case OMPC_release:
   case OMPC_relaxed:
   case OMPC_depend:
   case OMPC_device:
   case OMPC_threads:
   case OMPC_simd:
   case OMPC_map:
   case OMPC_num_teams:
   case OMPC_thread_limit:
   case OMPC_priority:
   case OMPC_grainsize:
   case OMPC_nogroup:
   case OMPC_num_tasks:
   case OMPC_hint:
   case OMPC_defaultmap:
   case OMPC_unknown:
   case OMPC_uniform:
   case OMPC_to:
   case OMPC_from:
   case OMPC_use_device_ptr:
   case OMPC_is_device_ptr:
   case OMPC_unified_address:
   case OMPC_unified_shared_memory:
   case OMPC_reverse_offload:
   case OMPC_dynamic_allocators:
   case OMPC_atomic_default_mem_order:
   case OMPC_device_type:
   case OMPC_match:
   case OMPC_nontemporal:
   case OMPC_order:
   case OMPC_destroy:
   case OMPC_detach:
     break;
   }
 
   return nullptr;
 }
 
 /// Gets the address of the original, non-captured, expression used in the
 /// clause as the preinitializer.
 static Stmt **getAddrOfExprAsWritten(Stmt *S) {
   if (!S)
     return nullptr;
   if (auto *DS = dyn_cast<DeclStmt>(S)) {
     assert(DS->isSingleDecl() && "Only single expression must be captured.");
     if (auto *OED = dyn_cast<OMPCapturedExprDecl>(DS->getSingleDecl()))
       return OED->getInitAddress();
   }
   return nullptr;
 }
 
 OMPClause::child_range OMPIfClause::used_children() {
   if (Stmt **C = getAddrOfExprAsWritten(getPreInitStmt()))
     return child_range(C, C + 1);
   return child_range(&Condition, &Condition + 1);
 }
 
 OMPClause::child_range OMPGrainsizeClause::used_children() {
   if (Stmt **C = getAddrOfExprAsWritten(getPreInitStmt()))
     return child_range(C, C + 1);
   return child_range(&Grainsize, &Grainsize + 1);
 }
 
 OMPClause::child_range OMPNumTasksClause::used_children() {
   if (Stmt **C = getAddrOfExprAsWritten(getPreInitStmt()))
     return child_range(C, C + 1);
   return child_range(&NumTasks, &NumTasks + 1);
 }
 
 OMPClause::child_range OMPFinalClause::used_children() {
   if (Stmt **C = getAddrOfExprAsWritten(getPreInitStmt()))
     return child_range(C, C + 1);
   return child_range(&Condition, &Condition + 1);
 }
 
 OMPClause::child_range OMPPriorityClause::used_children() {
   if (Stmt **C = getAddrOfExprAsWritten(getPreInitStmt()))
     return child_range(C, C + 1);
   return child_range(&Priority, &Priority + 1);
 }
 
 OMPOrderedClause *OMPOrderedClause::Create(const ASTContext &C, Expr *Num,
                                            unsigned NumLoops,
                                            SourceLocation StartLoc,
                                            SourceLocation LParenLoc,
                                            SourceLocation EndLoc) {
   void *Mem = C.Allocate(totalSizeToAlloc<Expr *>(2 * NumLoops));
   auto *Clause =
       new (Mem) OMPOrderedClause(Num, NumLoops, StartLoc, LParenLoc, EndLoc);
   for (unsigned I = 0; I < NumLoops; ++I) {
     Clause->setLoopNumIterations(I, nullptr);
     Clause->setLoopCounter(I, nullptr);
   }
   return Clause;
 }
 
 OMPOrderedClause *OMPOrderedClause::CreateEmpty(const ASTContext &C,
                                                 unsigned NumLoops) {
   void *Mem = C.Allocate(totalSizeToAlloc<Expr *>(2 * NumLoops));
   auto *Clause = new (Mem) OMPOrderedClause(NumLoops);
   for (unsigned I = 0; I < NumLoops; ++I) {
     Clause->setLoopNumIterations(I, nullptr);
     Clause->setLoopCounter(I, nullptr);
   }
   return Clause;
 }
 
 void OMPOrderedClause::setLoopNumIterations(unsigned NumLoop,
                                             Expr *NumIterations) {
   assert(NumLoop < NumberOfLoops && "out of loops number.");
   getTrailingObjects<Expr *>()[NumLoop] = NumIterations;
 }
 
 ArrayRef<Expr *> OMPOrderedClause::getLoopNumIterations() const {
   return llvm::makeArrayRef(getTrailingObjects<Expr *>(), NumberOfLoops);
 }
 
 void OMPOrderedClause::setLoopCounter(unsigned NumLoop, Expr *Counter) {
   assert(NumLoop < NumberOfLoops && "out of loops number.");
   getTrailingObjects<Expr *>()[NumberOfLoops + NumLoop] = Counter;
 }
 
 Expr *OMPOrderedClause::getLoopCounter(unsigned NumLoop) {
   assert(NumLoop <