[OpenCL] Support pipe keyword in C++ mode

[svenvh]

Summary

Support the OpenCL C pipe feature in C++ for OpenCL mode, to preserve backwards compatibility with OpenCL C.

[Anastasia]

LGTM! Thanks!

include/clang/Basic/TokenKinds.def

 KEYWORD(__builtin_astype            , KEYOPENCLC | KEYOPENCLCXX)
 KEYWORD(vec_step                    , KEYOPENCLC | KEYALTIVEC | KEYZVECTOR)
 #define GENERIC_IMAGE_TYPE(ImgType, Id) KEYWORD(ImgType##_t, KEYOPENCLC | KEYOPENCLCXX)
 #include "clang/Basic/OpenCLImageTypes.def"
 
 // OpenMP Type Traits
 KEYWORD(__builtin_omp_required_simd_align, KEYALL)
 
-KEYWORD(pipe                        , KEYOPENCLC)
+KEYWORD(pipe                        , KEYOPENCLC | KEYOPENCLCXX)
 
 // Borland Extensions.
 KEYWORD(__pascal                    , KEYALL)
 
 // Altivec Extension.
 KEYWORD(__vector                    , KEYALTIVEC|KEYZVECTOR)
 KEYWORD(__pixel                     , KEYALTIVEC)
 KEYWORD(__bool                      , KEYALTIVEC|KEYZVECTOR)

lib/Basic/Builtins.cpp

bool MathBuiltinsUnsupported =
     LangOpts.NoMathBuiltin && BuiltinInfo.HeaderName &&
     llvm::StringRef(BuiltinInfo.HeaderName).equals("math.h");
   bool GnuModeUnsupported = !LangOpts.GNUMode && (BuiltinInfo.Langs & GNU_LANG);
   bool MSModeUnsupported =
       !LangOpts.MicrosoftExt && (BuiltinInfo.Langs & MS_LANG);
   bool ObjCUnsupported = !LangOpts.ObjC && BuiltinInfo.Langs == OBJC_LANG;
   bool OclC1Unsupported = (LangOpts.OpenCLVersion / 100) != 1 &&
                           (BuiltinInfo.Langs & ALL_OCLC_LANGUAGES ) ==  OCLC1X_LANG;
-  bool OclC2Unsupported = LangOpts.OpenCLVersion != 200 &&
-                          (BuiltinInfo.Langs & ALL_OCLC_LANGUAGES) == OCLC20_LANG;
+  bool OclC2Unsupported =
+      (LangOpts.OpenCLVersion != 200 && !LangOpts.OpenCLCPlusPlus) &&
   bool OclCUnsupported = !LangOpts.OpenCL &&
                          (BuiltinInfo.Langs & ALL_OCLC_LANGUAGES);
   bool OpenMPUnsupported = !LangOpts.OpenMP && BuiltinInfo.Langs == OMP_LANG;
   bool CPlusPlusUnsupported =
       !LangOpts.CPlusPlus && BuiltinInfo.Langs == CXX_LANG;
   return !BuiltinsUnsupported && !MathBuiltinsUnsupported && !OclCUnsupported &&
          !OclC1Unsupported && !OclC2Unsupported && !OpenMPUnsupported &&
          !GnuModeUnsupported && !MSModeUnsupported && !ObjCUnsupported &&

lib/Parse/ParseDecl.cpp

bool Parser::ParseImplicitInt(DeclSpec &DS, CXXScopeSpec *SS,
   if (!isTypeSpecifier(DSC) && !getLangOpts().CPlusPlus &&
       isValidAfterIdentifierInDeclarator(NextToken())) {
     // If this token is valid for implicit int, e.g. "static x = 4", then
     // we just avoid eating the identifier, so it will be parsed as the
     // identifier in the declarator.
     return false;
   }
 
+  // Early exit as Sema has a dedicated missing_actual_pipe_type diagnostic
+  // for incomplete declarations such as `pipe p`.
+  if (getLangOpts().OpenCLCPlusPlus && DS.isTypeSpecPipe())
+    return false;
+
   if (getLangOpts().CPlusPlus &&
       DS.getStorageClassSpec() == DeclSpec::SCS_auto) {
     // Don't require a type specifier if we have the 'auto' storage class
     // specifier in C++98 -- we'll promote it to a type specifier.
     if (SS)
       AnnotateScopeToken(*SS, /*IsNewAnnotation*/false);
     return false;
   }
case tok::kw___vector:
       break;
     case tok::kw___pixel:
       isInvalid = DS.SetTypeAltiVecPixel(true, Loc, PrevSpec, DiagID, Policy);
       break;
     case tok::kw___bool:
       isInvalid = DS.SetTypeAltiVecBool(true, Loc, PrevSpec, DiagID, Policy);
       break;
     case tok::kw_pipe:
-      if (!getLangOpts().OpenCL || (getLangOpts().OpenCLVersion < 200)) {
+      if (!getLangOpts().OpenCL || (getLangOpts().OpenCLVersion < 200 &&
+                                    !getLangOpts().OpenCLCPlusPlus)) {
         // OpenCL 2.0 defined this keyword. OpenCL 1.2 and earlier should
         // support the "pipe" word as identifier.
         Tok.getIdentifierInfo()->revertTokenIDToIdentifier();
         goto DoneWithDeclSpec;
       }
       isInvalid = DS.SetTypePipe(true, Loc, PrevSpec, DiagID, Policy);
       break;
 #define GENERIC_IMAGE_TYPE(ImgType, Id) \

 ///
 /// \param DisambiguatingWithExpression True to indicate that the purpose of
 /// this check is to disambiguate between an expression and a declaration.
 bool Parser::isDeclarationSpecifier(bool DisambiguatingWithExpression) {
   switch (Tok.getKind()) {
   default: return false;
 
   case tok::kw_pipe:
-    return getLangOpts().OpenCL && (getLangOpts().OpenCLVersion >= 200);
+    return (getLangOpts().OpenCL && getLangOpts().OpenCLVersion >= 200) ||
+           getLangOpts().OpenCLCPlusPlus;
 
   case tok::identifier:   // foo::bar
     // Unfortunate hack to support "Class.factoryMethod" notation.
     if (getLangOpts().ObjC && NextToken().is(tok::period))
       return false;
     if (TryAltiVecVectorToken())
       return true;
     LLVM_FALLTHROUGH;
void Parser::ParseDeclarator(Declarator &D) {
   ParseDeclaratorInternal(D, &Parser::ParseDirectDeclarator);
 }
 
 static bool isPtrOperatorToken(tok::TokenKind Kind, const LangOptions &Lang,
                                DeclaratorContext TheContext) {
   if (Kind == tok::star || Kind == tok::caret)
     return true;
 
-  if ((Kind == tok::kw_pipe) && Lang.OpenCL && (Lang.OpenCLVersion >= 200))
+  if (Kind == tok::kw_pipe &&
+      ((Lang.OpenCL && Lang.OpenCLVersion >= 200) || Lang.OpenCLCPlusPlus))
     return true;
 
   if (!Lang.CPlusPlus)
     return false;
 
   if (Kind == tok::amp)
     return true;
 

lib/Parse/ParseTentative.cpp

Parser::isCXXDeclarationSpecifier(Parser::TPResult BracedCastResult,
   case tok::kw___local:
   case tok::kw___global:
   case tok::kw___constant:
   case tok::kw___generic:
     // OpenCL access qualifiers
   case tok::kw___read_only:
   case tok::kw___write_only:
   case tok::kw___read_write:
+    // OpenCL pipe
+  case tok::kw_pipe:
 
     // GNU
   case tok::kw_restrict:
   case tok::kw__Complex:
   case tok::kw___attribute:
   case tok::kw___auto_type:
     return TPResult::True;
 

lib/Sema/SemaDecl.cpp

if (isMemberSpecialization && !NewFD->isInvalidDecl())
       CompleteMemberSpecialization(NewFD, Previous);
   }
 
   for (const ParmVarDecl *Param : NewFD->parameters()) {
     QualType PT = Param->getType();
 
     // OpenCL 2.0 pipe restrictions forbids pipe packet types to be non-value
     // types.
-    if (getLangOpts().OpenCLVersion >= 200) {
+    if (getLangOpts().OpenCLVersion >= 200 || getLangOpts().OpenCLCPlusPlus) {
       if(const PipeType *PipeTy = PT->getAs<PipeType>()) {
         QualType ElemTy = PipeTy->getElementType();
           if (ElemTy->isReferenceType() || ElemTy->isPointerType()) {
             Diag(Param->getTypeSpecStartLoc(), diag::err_reference_pipe_type );
             D.setInvalidType();
           }
       }
     }

lib/Sema/SemaType.cpp

if (S.getLangOpts().ImplicitInt) {
             << DS.getSourceRange()
             << FixItHint::CreateInsertion(DS.getBeginLoc(), "int");
       }
     } else if (!DS.hasTypeSpecifier()) {
       // C99 and C++ require a type specifier.  For example, C99 6.7.2p2 says:
       // "At least one type specifier shall be given in the declaration
       // specifiers in each declaration, and in the specifier-qualifier list in
       // each struct declaration and type name."
-      if (S.getLangOpts().CPlusPlus) {
+      if (S.getLangOpts().CPlusPlus && !DS.isTypeSpecPipe()) {
         S.Diag(DeclLoc, diag::err_missing_type_specifier)
           << DS.getSourceRange();
 
         // When this occurs in C++ code, often something is very broken with the
         // value being declared, poison it as invalid so we don't get chains of
         // errors.
         declarator.setInvalidType(true);
-      } else if (S.getLangOpts().OpenCLVersion >= 200 && DS.isTypeSpecPipe()){
+      } else if ((S.getLangOpts().OpenCLVersion >= 200 ||
+                  S.getLangOpts().OpenCLCPlusPlus) &&
+                 DS.isTypeSpecPipe()) {
         S.Diag(DeclLoc, diag::err_missing_actual_pipe_type)
           << DS.getSourceRange();
         declarator.setInvalidType(true);
       } else {
         S.Diag(DeclLoc, diag::ext_missing_type_specifier)
           << DS.getSourceRange();
       }
     }

test/SemaOpenCL/invalid-pipes-cl2.0.cl

 // RUN: %clang_cc1 %s -verify -pedantic -fsyntax-only -cl-std=CL2.0
+// RUN: %clang_cc1 %s -verify -pedantic -fsyntax-only -cl-std=c++
 
 global pipe int gp;            // expected-error {{type '__global read_only pipe int' can only be used as a function parameter in OpenCL}}
 global reserve_id_t rid;          // expected-error {{the '__global reserve_id_t' type cannot be used to declare a program scope variable}}
 
-extern pipe write_only int get_pipe(); // expected-error {{type '__global write_only pipe int (void)' can only be used as a function parameter in OpenCL}}
+extern pipe write_only int get_pipe(); // expected-error-re{{type '__global write_only pipe int ({{(void)?}})' can only be used as a function parameter in OpenCL}}
 
 kernel void test_invalid_reserved_id(reserve_id_t ID) { // expected-error {{'reserve_id_t' cannot be used as the type of a kernel parameter}}
 }
 
 void test1(pipe int *p) {// expected-error {{pipes packet types cannot be of reference type}}
 }
 void test2(pipe p) {// expected-error {{missing actual type specifier for pipe}}
 }

 pipe_int_t test6() {} // expected-error{{declaring function return value of type 'pipe_int_t' (aka 'read_only pipe int') is not allowed}}
 
 bool test_id_comprision(void) {
   reserve_id_t id1, id2;
   return (id1 == id2);          // expected-error {{invalid operands to binary expression ('reserve_id_t' and 'reserve_id_t')}}
 }
 
 // Tests ASTContext::mergeTypes rejects this.
+#ifndef __OPENCL_CPP_VERSION__
 int f(pipe int x, int y); // expected-note {{previous declaration is here}}
 int f(x, y) // expected-error {{conflicting types for 'f}}
 pipe short x;
 int y;
 {
     return y;
 }
+#endif