[clang] NFC: remove duplicated code around type constraint and templ arg subst

[mizvekov]

Summary

Signed-off-by: Matheus Izvekov <[e-mail]>

[rsmith]

Nice!

clang/include/clang/AST/DeclTemplate.h

public:
   /// Returns the explicit template arguments that were given.
   const TemplateArgumentLoc *getTemplateArgs() const {
     return getTrailingObjects<TemplateArgumentLoc>();
   }
 
   /// Returns the number of explicit template arguments that were given.
   unsigned getNumTemplateArgs() const { return NumArgs; }
 
+  llvm::ArrayRef<TemplateArgumentLoc> arguments() const {
+    return llvm::makeArrayRef(getTemplateArgs(), getNumTemplateArgs());
+  }
+
   /// Returns the nth template argument.
   const TemplateArgumentLoc &getTemplateArg(unsigned I) const {
     assert(I < getNumTemplateArgs() && "template arg index out of range");
     return getTemplateArgs()[I];
   }
 
   SourceLocation getLAngleLoc() const {
     return AngleLocs.getBegin();

clang/include/clang/Sema/Sema.h

 
   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,
+
+  bool SubstTypeConstraint(TemplateTypeParmDecl *Inst, const TypeConstraint *TC,
                            const MultiLevelTemplateArgumentList &TemplateArgs);
 
   bool InstantiateDefaultArgument(SourceLocation CallLoc, FunctionDecl *FD,
                                   ParmVarDecl *Param);
   void InstantiateExceptionSpec(SourceLocation PointOfInstantiation,
                                 FunctionDecl *Function);
   bool CheckInstantiatedFunctionTemplateConstraints(
       SourceLocation PointOfInstantiation, FunctionDecl *Decl,
       ArrayRef<TemplateArgument> TemplateArgs,

clang/lib/Sema/SemaTemplate.cpp

if (auto *TTP = dyn_cast<TemplateTypeParmDecl>(TemplateParam)) {
       // substitute it directly.
       auto *NewTTP = TemplateTypeParmDecl::Create(
           SemaRef.Context, DC, TTP->getBeginLoc(), TTP->getLocation(),
           /*Depth*/ 0, Depth1IndexAdjustment + TTP->getIndex(),
           TTP->getIdentifier(), TTP->wasDeclaredWithTypename(),
           TTP->isParameterPack(), TTP->hasTypeConstraint(),
           TTP->isExpandedParameterPack() ?
           llvm::Optional<unsigned>(TTP->getNumExpansionParameters()) : None);
-      if (const auto *TC = TTP->getTypeConstraint()) {
-        TemplateArgumentListInfo TransformedArgs;
-        const auto *ArgsAsWritten = TC->getTemplateArgsAsWritten();
-        if (!ArgsAsWritten ||
-            SemaRef.Subst(ArgsAsWritten->getTemplateArgs(),
-                          ArgsAsWritten->NumTemplateArgs, TransformedArgs,
-                          Args))
-          SemaRef.AttachTypeConstraint(
-              TC->getNestedNameSpecifierLoc(), TC->getConceptNameInfo(),
-              TC->getNamedConcept(), ArgsAsWritten ? &TransformedArgs : nullptr,
-              NewTTP,
-              NewTTP->isParameterPack()
-                 ? cast<CXXFoldExpr>(TC->getImmediatelyDeclaredConstraint())
-                     ->getEllipsisLoc()
-                 : SourceLocation());
-      }
+      if (const auto *TC = TTP->getTypeConstraint())
+        SemaRef.SubstTypeConstraint(NewTTP, TC, Args);
       if (TTP->hasDefaultArgument()) {
         TypeSourceInfo *InstantiatedDefaultArg =
             SemaRef.SubstType(TTP->getDefaultArgumentInfo(), Args,
                               TTP->getDefaultArgumentLoc(), TTP->getDeclName());
         if (InstantiatedDefaultArg)
           NewTTP->setDefaultArgument(InstantiatedDefaultArg);
       }
       SemaRef.CurrentInstantiationScope->InstantiatedLocal(TemplateParam,

clang/lib/Sema/SemaTemplateDeduction.cpp

FinishTemplateArgumentDeduction(
   // arguments of the class template partial specialization, and
   // verify that the instantiated template arguments are both valid
   // and are equivalent to the template arguments originally provided
   // to the class template.
   LocalInstantiationScope InstScope(S);
   auto *Template = Partial->getSpecializedTemplate();
   const ASTTemplateArgumentListInfo *PartialTemplArgInfo =
       Partial->getTemplateArgsAsWritten();
-  const TemplateArgumentLoc *PartialTemplateArgs =
-      PartialTemplArgInfo->getTemplateArgs();
 
   TemplateArgumentListInfo InstArgs(PartialTemplArgInfo->LAngleLoc,
                                     PartialTemplArgInfo->RAngleLoc);
 
-  if (S.Subst(PartialTemplateArgs, PartialTemplArgInfo->NumTemplateArgs,
-              InstArgs, MultiLevelTemplateArgumentList(*DeducedArgumentList))) {
+  if (S.SubstTemplateArguments(
+          PartialTemplArgInfo->arguments(),
+          MultiLevelTemplateArgumentList(*DeducedArgumentList), InstArgs)) {
     unsigned ArgIdx = InstArgs.size(), ParamIdx = ArgIdx;
     if (ParamIdx >= Partial->getTemplateParameters()->size())
       ParamIdx = Partial->getTemplateParameters()->size() - 1;
 
     Decl *Param = const_cast<NamedDecl *>(
         Partial->getTemplateParameters()->getParam(ParamIdx));
     Info.Param = makeTemplateParameter(Param);
-    Info.FirstArg = PartialTemplateArgs[ArgIdx].getArgument();
+    Info.FirstArg = (*PartialTemplArgInfo)[ArgIdx].getArgument();
     return Sema::TDK_SubstitutionFailure;
   }
 
   bool ConstraintsNotSatisfied;
   SmallVector<TemplateArgument, 4> ConvertedInstArgs;
   if (S.CheckTemplateArgumentList(Template, Partial->getLocation(), InstArgs,
                                   false, ConvertedInstArgs,
                                   /*UpdateArgsWithConversions=*/true,

clang/lib/Sema/SemaTemplateInstantiate.cpp

struct GetContainedInventedTypeParmVisitor :
 
     TemplateTypeParmDecl *VisitPackExpansionType(const PackExpansionType *T) {
       return Visit(T->getPattern());
     }
   };
 
 } // namespace
 
+bool Sema::SubstTypeConstraint(
+    TemplateTypeParmDecl *Inst, const TypeConstraint *TC,
+    const MultiLevelTemplateArgumentList &TemplateArgs) {
+  const ASTTemplateArgumentListInfo *TemplArgInfo =
+      TC->getTemplateArgsAsWritten();
+  TemplateArgumentListInfo InstArgs;
+
+  if (TemplArgInfo) {
+    InstArgs.setLAngleLoc(TemplArgInfo->LAngleLoc);
+    InstArgs.setRAngleLoc(TemplArgInfo->RAngleLoc);
+    if (SubstTemplateArguments(TemplArgInfo->arguments(), TemplateArgs,
+                               InstArgs))
+      return true;
+  }
+  return AttachTypeConstraint(
+      TC->getNestedNameSpecifierLoc(), TC->getConceptNameInfo(),
+      TC->getNamedConcept(), &InstArgs, Inst,
+      Inst->isParameterPack()
+          ? cast<CXXFoldExpr>(TC->getImmediatelyDeclaredConstraint())
+                ->getEllipsisLoc()
+          : SourceLocation());
+}
+
 ParmVarDecl *Sema::SubstParmVarDecl(ParmVarDecl *OldParm,
                             const MultiLevelTemplateArgumentList &TemplateArgs,
                                     int indexAdjustment,
                                     Optional<unsigned> NumExpansions,
                                     bool ExpectParameterPack) {
   TypeSourceInfo *OldDI = OldParm->getTypeSourceInfo();
   TypeSourceInfo *NewDI = nullptr;
 
if (const TypeConstraint *TC = TTP->getTypeConstraint()) {
       auto *Inst = cast_or_null<TemplateTypeParmDecl>(
           FindInstantiatedDecl(TTP->getLocation(), TTP, TemplateArgs));
       // We will first get here when instantiating the abbreviated function
       // template's described function, but we might also get here later.
       // Make sure we do not instantiate the TypeConstraint more than once.
       if (Inst && !Inst->getTypeConstraint()) {
         // TODO: Concepts: do not instantiate the constraint (delayed constraint
         // substitution)
-        const ASTTemplateArgumentListInfo *TemplArgInfo
-          = TC->getTemplateArgsAsWritten();
-        TemplateArgumentListInfo InstArgs;
-
-        if (TemplArgInfo) {
-          InstArgs.setLAngleLoc(TemplArgInfo->LAngleLoc);
-          InstArgs.setRAngleLoc(TemplArgInfo->RAngleLoc);
-          if (Subst(TemplArgInfo->getTemplateArgs(),
-                    TemplArgInfo->NumTemplateArgs, InstArgs, TemplateArgs))
-            return nullptr;
-        }
-        if (AttachTypeConstraint(
-                TC->getNestedNameSpecifierLoc(), TC->getConceptNameInfo(),
-                TC->getNamedConcept(), TemplArgInfo ? &InstArgs : nullptr, Inst,
-                TTP->isParameterPack()
-                    ? cast<CXXFoldExpr>(TC->getImmediatelyDeclaredConstraint())
-                          ->getEllipsisLoc()
-                    : SourceLocation()))
+        if (SubstTypeConstraint(Inst, TC, TemplateArgs))
           return nullptr;
       }
     }
   }
 
   ParmVarDecl *NewParm = CheckParameter(Context.getTranslationUnitDecl(),
                                         OldParm->getInnerLocStart(),
                                         OldParm->getLocation(),
Sema::SubstTemplateName(NestedNameSpecifierLoc QualifierLoc,
                         const MultiLevelTemplateArgumentList &TemplateArgs) {
   TemplateInstantiator Instantiator(*this, TemplateArgs, Loc,
                                     DeclarationName());
   CXXScopeSpec SS;
   SS.Adopt(QualifierLoc);
   return Instantiator.TransformTemplateName(SS, Name, Loc);
 }
 
-bool Sema::Subst(const TemplateArgumentLoc *Args, unsigned NumArgs,
-                 TemplateArgumentListInfo &Result,
-                 const MultiLevelTemplateArgumentList &TemplateArgs) {
-  TemplateInstantiator Instantiator(*this, TemplateArgs, SourceLocation(),
-                                    DeclarationName());
-
-  return Instantiator.TransformTemplateArguments(Args, NumArgs, Result);
-}
-
 static const Decl *getCanonicalParmVarDecl(const Decl *D) {
   // When storing ParmVarDecls in the local instantiation scope, we always
   // want to use the ParmVarDecl from the canonical function declaration,
   // since the map is then valid for any redeclaration or definition of that
   // function.
   if (const ParmVarDecl *PV = dyn_cast<ParmVarDecl>(D)) {
     if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(PV->getDeclContext())) {
       unsigned i = PV->getFunctionScopeIndex();

clang/lib/Sema/SemaTemplateInstantiateDecl.cpp

Decl *TemplateDeclInstantiator::VisitFunctionDecl(
 
   if (DependentFunctionTemplateSpecializationInfo *Info
         = D->getDependentSpecializationInfo()) {
     assert(isFriend && "non-friend has dependent specialization info?");
 
     // Instantiate the explicit template arguments.
     TemplateArgumentListInfo ExplicitArgs(Info->getLAngleLoc(),
                                           Info->getRAngleLoc());
-    if (SemaRef.Subst(Info->getTemplateArgs(), Info->getNumTemplateArgs(),
-                      ExplicitArgs, TemplateArgs))
+    if (SemaRef.SubstTemplateArguments(Info->arguments(), TemplateArgs,
+                                       ExplicitArgs))
       return nullptr;
 
     // Map the candidate templates to their instantiations.
     for (unsigned I = 0, E = Info->getNumTemplates(); I != E; ++I) {
       Decl *Temp = SemaRef.FindInstantiatedDecl(D->getLocation(),
                                                 Info->getTemplate(I),
                                                 TemplateArgs);
       if (!Temp) return nullptr;
Decl *TemplateDeclInstantiator::VisitFunctionDecl(
   } else if (const ASTTemplateArgumentListInfo *Info =
                  D->getTemplateSpecializationArgsAsWritten()) {
     // The name of this function was written as a template-id.
     SemaRef.LookupQualifiedName(Previous, DC);
 
     // Instantiate the explicit template arguments.
     TemplateArgumentListInfo ExplicitArgs(Info->getLAngleLoc(),
                                           Info->getRAngleLoc());
-    if (SemaRef.Subst(Info->getTemplateArgs(), Info->getNumTemplateArgs(),
-                      ExplicitArgs, TemplateArgs))
+    if (SemaRef.SubstTemplateArguments(Info->arguments(), TemplateArgs,
+                                       ExplicitArgs))
       return nullptr;
 
     if (SemaRef.CheckFunctionTemplateSpecialization(Function,
                                                     &ExplicitArgs,
                                                     Previous))
       Function->setInvalidDecl();
 
     IsExplicitSpecialization = true;
Decl *TemplateDeclInstantiator::VisitCXXMethodDecl(
   // the explicit template arguments.
   if (DependentFunctionTemplateSpecializationInfo *Info
         = D->getDependentSpecializationInfo()) {
     assert(isFriend && "non-friend has dependent specialization info?");
 
     // Instantiate the explicit template arguments.
     TemplateArgumentListInfo ExplicitArgs(Info->getLAngleLoc(),
                                           Info->getRAngleLoc());
-    if (SemaRef.Subst(Info->getTemplateArgs(), Info->getNumTemplateArgs(),
-                      ExplicitArgs, TemplateArgs))
+    if (SemaRef.SubstTemplateArguments(Info->arguments(), TemplateArgs,
+                                       ExplicitArgs))
       return nullptr;
 
     // Map the candidate templates to their instantiations.
     for (unsigned I = 0, E = Info->getNumTemplates(); I != E; ++I) {
       Decl *Temp = SemaRef.FindInstantiatedDecl(D->getLocation(),
                                                 Info->getTemplate(I),
                                                 TemplateArgs);
       if (!Temp) return nullptr;
if (DependentFunctionTemplateSpecializationInfo *Info
     IsExplicitSpecialization = true;
   } else if (const ASTTemplateArgumentListInfo *Info =
                  ClassScopeSpecializationArgs.getValueOr(
                      D->getTemplateSpecializationArgsAsWritten())) {
     SemaRef.LookupQualifiedName(Previous, DC);
 
     TemplateArgumentListInfo ExplicitArgs(Info->getLAngleLoc(),
                                           Info->getRAngleLoc());
-    if (SemaRef.Subst(Info->getTemplateArgs(), Info->getNumTemplateArgs(),
-                      ExplicitArgs, TemplateArgs))
+    if (SemaRef.SubstTemplateArguments(Info->arguments(), TemplateArgs,
+                                       ExplicitArgs))
       return nullptr;
 
     if (SemaRef.CheckFunctionTemplateSpecialization(Method,
                                                     &ExplicitArgs,
                                                     Previous))
       Method->setInvalidDecl();
 
     IsExplicitSpecialization = true;
Decl *TemplateDeclInstantiator::VisitTemplateTypeParmDecl(
   if (auto *TC = D->getTypeConstraint()) {
     if (!D->isImplicit()) {
       // Invented template parameter type constraints will be instantiated with
       // the corresponding auto-typed parameter as it might reference other
       // parameters.
 
       // TODO: Concepts: do not instantiate the constraint (delayed constraint
       // substitution)
-      const ASTTemplateArgumentListInfo *TemplArgInfo
-        = TC->getTemplateArgsAsWritten();
-      TemplateArgumentListInfo InstArgs;
-
-      if (TemplArgInfo) {
-        InstArgs.setLAngleLoc(TemplArgInfo->LAngleLoc);
-        InstArgs.setRAngleLoc(TemplArgInfo->RAngleLoc);
-        if (SemaRef.Subst(TemplArgInfo->getTemplateArgs(),
-                          TemplArgInfo->NumTemplateArgs,
-                          InstArgs, TemplateArgs))
-          return nullptr;
-      }
-      if (SemaRef.AttachTypeConstraint(
-              TC->getNestedNameSpecifierLoc(), TC->getConceptNameInfo(),
-              TC->getNamedConcept(), &InstArgs, Inst,
-              D->isParameterPack()
-                  ? cast<CXXFoldExpr>(TC->getImmediatelyDeclaredConstraint())
-                      ->getEllipsisLoc()
-                  : SourceLocation()))
+      if (SemaRef.SubstTypeConstraint(Inst, TC, TemplateArgs))
         return nullptr;
     }
   }
   if (D->hasDefaultArgument() && !D->defaultArgumentWasInherited()) {
     TypeSourceInfo *InstantiatedDefaultArg =
         SemaRef.SubstType(D->getDefaultArgumentInfo(), TemplateArgs,
                           D->getDefaultArgumentLoc(), D->getDeclName());
     if (InstantiatedDefaultArg)
TemplateDeclInstantiator::VisitClassTemplateSpecializationDecl(
   // specialization.
   TemplateSpecializationTypeLoc Loc = D->getTypeAsWritten()->getTypeLoc().
                                         castAs<TemplateSpecializationTypeLoc>();
   TemplateArgumentListInfo InstTemplateArgs(Loc.getLAngleLoc(),
                                             Loc.getRAngleLoc());
   SmallVector<TemplateArgumentLoc, 4> ArgLocs;
   for (unsigned I = 0; I != Loc.getNumArgs(); ++I)
     ArgLocs.push_back(Loc.getArgLoc(I));
-  if (SemaRef.Subst(ArgLocs.data(), ArgLocs.size(),
-                    InstTemplateArgs, TemplateArgs))
+  if (SemaRef.SubstTemplateArguments(ArgLocs, TemplateArgs, InstTemplateArgs))
     return nullptr;
 
   // Check that the template argument list is well-formed for this
   // class template.
   SmallVector<TemplateArgument, 4> Converted;
   if (SemaRef.CheckTemplateArgumentList(InstClassTemplate,
                                         D->getLocation(),
                                         InstTemplateArgs,
Decl *TemplateDeclInstantiator::VisitVarTemplateSpecializationDecl(
   if (!InstVarTemplate)
     return nullptr;
 
   // Substitute the current template arguments.
   const TemplateArgumentListInfo &TemplateArgsInfo = D->getTemplateArgsInfo();
   VarTemplateArgsInfo.setLAngleLoc(TemplateArgsInfo.getLAngleLoc());
   VarTemplateArgsInfo.setRAngleLoc(TemplateArgsInfo.getRAngleLoc());
 
-  if (SemaRef.Subst(TemplateArgsInfo.getArgumentArray(),
-                    TemplateArgsInfo.size(), VarTemplateArgsInfo, TemplateArgs))
+  if (SemaRef.SubstTemplateArguments(TemplateArgsInfo.arguments(), TemplateArgs,
+                                     VarTemplateArgsInfo))
     return nullptr;
 
   // Check that the template argument list is well-formed for this template.
   SmallVector<TemplateArgument, 4> Converted;
   if (SemaRef.CheckTemplateArgumentList(InstVarTemplate, D->getLocation(),
                                         VarTemplateArgsInfo, false, Converted,
                                         /*UpdateArgsWithConversion=*/true))
     return nullptr;
if (!InstParams)
     return nullptr;
 
   // Substitute into the template arguments of the class template partial
   // specialization.
   const ASTTemplateArgumentListInfo *TemplArgInfo
     = PartialSpec->getTemplateArgsAsWritten();
   TemplateArgumentListInfo InstTemplateArgs(TemplArgInfo->LAngleLoc,
                                             TemplArgInfo->RAngleLoc);
-  if (SemaRef.Subst(TemplArgInfo->getTemplateArgs(),
-                    TemplArgInfo->NumTemplateArgs,
-                    InstTemplateArgs, TemplateArgs))
+  if (SemaRef.SubstTemplateArguments(TemplArgInfo->arguments(), TemplateArgs,
+                                     InstTemplateArgs))
     return nullptr;
 
   // Check that the template argument list is well-formed for this
   // class template.
   SmallVector<TemplateArgument, 4> Converted;
   if (SemaRef.CheckTemplateArgumentList(ClassTemplate,
                                         PartialSpec->getLocation(),
                                         InstTemplateArgs,
if (!InstParams)
     return nullptr;
 
   // Substitute into the template arguments of the variable template partial
   // specialization.
   const ASTTemplateArgumentListInfo *TemplArgInfo
     = PartialSpec->getTemplateArgsAsWritten();
   TemplateArgumentListInfo InstTemplateArgs(TemplArgInfo->LAngleLoc,
                                             TemplArgInfo->RAngleLoc);
-  if (SemaRef.Subst(TemplArgInfo->getTemplateArgs(),
-                    TemplArgInfo->NumTemplateArgs,
-                    InstTemplateArgs, TemplateArgs))
+  if (SemaRef.SubstTemplateArguments(TemplArgInfo->arguments(), TemplateArgs,
+                                     InstTemplateArgs))
     return nullptr;
 
   // Check that the template argument list is well-formed for this
   // class template.
   SmallVector<TemplateArgument, 4> Converted;
   if (SemaRef.CheckTemplateArgumentList(VarTemplate, PartialSpec->getLocation(),
                                         InstTemplateArgs, false, Converted))
     return nullptr;