Implement OpenCL event_t as Clang builtin type, including event_t related OpenCL restrictions (OpenCL 1.2 spec 6.9)

llvm-svn: 172973

30 files changed, 146 insertions, 8 deletions

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index ace9dc0..b18fa67 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -893,6 +893,8 @@ void ASTContext::InitBuiltinTypes(const TargetInfo &Target) {
     InitBuiltinType(OCLImage2dTy, BuiltinType::OCLImage2d);
     InitBuiltinType(OCLImage2dArrayTy, BuiltinType::OCLImage2dArray);
     InitBuiltinType(OCLImage3dTy, BuiltinType::OCLImage3d);
+
+    InitBuiltinType(OCLEventTy, BuiltinType::OCLEvent);
   }
   
   // Builtin type for __objc_yes and __objc_no
@@ -1434,6 +1436,7 @@ ASTContext::getTypeInfoImpl(const Type *T) const {
       Width = Target->getPointerWidth(0); 
       Align = Target->getPointerAlign(0);
       break;
+    case BuiltinType::OCLEvent:
     case BuiltinType::OCLImage1d:
     case BuiltinType::OCLImage1dArray:
     case BuiltinType::OCLImage1dBuffer:
@@ -4895,6 +4898,7 @@ static char getObjCEncodingForPrimitiveKind(const ASTContext *C,
     case BuiltinType::OCLImage2d:
     case BuiltinType::OCLImage2dArray:
     case BuiltinType::OCLImage3d:
+    case BuiltinType::OCLEvent:
     case BuiltinType::Dependent:
 #define BUILTIN_TYPE(KIND, ID)
 #define PLACEHOLDER_TYPE(KIND, ID) \
diff --git a/clang/lib/AST/Expr.cpp b/clang/lib/AST/Expr.cpp
index 718002f..e3ff29d 100644
--- a/clang/lib/AST/Expr.cpp
+++ b/clang/lib/AST/Expr.cpp
@@ -1400,6 +1400,7 @@ void CastExpr::CheckCastConsistency() const {
   case CK_ARCConsumeObject:
   case CK_ARCReclaimReturnedObject:
   case CK_ARCExtendBlockObject:
+  case CK_ZeroToOCLEvent:
     assert(!getType()->isBooleanType() && "unheralded conversion to bool");
     goto CheckNoBasePath;
 
@@ -1531,6 +1532,8 @@ const char *CastExpr::getCastKindName() const {
     return "CopyAndAutoreleaseBlockObject";
   case CK_BuiltinFnToFnPtr:
     return "BuiltinFnToFnPtr";
+  case CK_ZeroToOCLEvent:
+    return "ZeroToOCLEvent";
   }
 
   llvm_unreachable("Unhandled cast kind!");
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index 9965e12..64fd40b 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -5372,6 +5372,7 @@ bool IntExprEvaluator::VisitCastExpr(const CastExpr *E) {
   case CK_IntegralComplexCast:
   case CK_IntegralComplexToFloatingComplex:
   case CK_BuiltinFnToFnPtr:
+  case CK_ZeroToOCLEvent:
     llvm_unreachable("invalid cast kind for integral value");
 
   case CK_BitCast:
@@ -5859,6 +5860,7 @@ bool ComplexExprEvaluator::VisitCastExpr(const CastExpr *E) {
   case CK_ARCExtendBlockObject:
   case CK_CopyAndAutoreleaseBlockObject:
   case CK_BuiltinFnToFnPtr:
+  case CK_ZeroToOCLEvent:
     llvm_unreachable("invalid cast kind for complex value");
 
   case CK_LValueToRValue:
diff --git a/clang/lib/AST/ItaniumMangle.cpp b/clang/lib/AST/ItaniumMangle.cpp
index 65e630e..926384d 100644
--- a/clang/lib/AST/ItaniumMangle.cpp
+++ b/clang/lib/AST/ItaniumMangle.cpp
@@ -1886,6 +1886,7 @@ void CXXNameMangler::mangleType(const BuiltinType *T) {
   case BuiltinType::OCLImage2d: Out << "11ocl_image2d"; break;
   case BuiltinType::OCLImage2dArray: Out << "16ocl_image2darray"; break;
   case BuiltinType::OCLImage3d: Out << "11ocl_image3d"; break;
+  case BuiltinType::OCLEvent: Out << "9ocl_event"; break;
   }
 }
 
diff --git a/clang/lib/AST/MicrosoftMangle.cpp b/clang/lib/AST/MicrosoftMangle.cpp
index bd0125d..0b77ac8 100644
--- a/clang/lib/AST/MicrosoftMangle.cpp
+++ b/clang/lib/AST/MicrosoftMangle.cpp
@@ -1060,6 +1060,7 @@ void MicrosoftCXXNameMangler::mangleType(const BuiltinType *T,
   case BuiltinType::OCLImage2d: Out << "PAUocl_image2d@@"; break;
   case BuiltinType::OCLImage2dArray: Out << "PAUocl_image2darray@@"; break;
   case BuiltinType::OCLImage3d: Out << "PAUocl_image3d@@"; break;
+  case BuiltinType::OCLEvent: Out << "PAUocl_event@@"; break;
  
   case BuiltinType::NullPtr: Out << "$$T"; break;
 
diff --git a/clang/lib/AST/NSAPI.cpp b/clang/lib/AST/NSAPI.cpp
index 35cc7d0..c8cf920 100644
--- a/clang/lib/AST/NSAPI.cpp
+++ b/clang/lib/AST/NSAPI.cpp
@@ -351,6 +351,7 @@ NSAPI::getNSNumberFactoryMethodKind(QualType T) const {
   case BuiltinType::OCLImage2d:
   case BuiltinType::OCLImage2dArray:
   case BuiltinType::OCLImage3d:
+  case BuiltinType::OCLEvent:
   case BuiltinType::BoundMember:
   case BuiltinType::Dependent:
   case BuiltinType::Overload:
diff --git a/clang/lib/AST/Type.cpp b/clang/lib/AST/Type.cpp
index 45ec4ed..524d005 100644
--- a/clang/lib/AST/Type.cpp
+++ b/clang/lib/AST/Type.cpp
@@ -1518,6 +1518,7 @@ StringRef BuiltinType::getName(const PrintingPolicy &Policy) const {
   case OCLImage2d:        return "image2d_t";
   case OCLImage2dArray:   return "image2d_array_t";
   case OCLImage3d:        return "image3d_t";
+  case OCLEvent:          return "event_t";
   }
   
   llvm_unreachable("Invalid builtin type.");
diff --git a/clang/lib/AST/TypeLoc.cpp b/clang/lib/AST/TypeLoc.cpp
index a5baf70..3efa148 100644
--- a/clang/lib/AST/TypeLoc.cpp
+++ b/clang/lib/AST/TypeLoc.cpp
@@ -268,6 +268,7 @@ TypeSpecifierType BuiltinTypeLoc::getWrittenTypeSpec() const {
   case BuiltinType::OCLImage2d:
   case BuiltinType::OCLImage2dArray:
   case BuiltinType::OCLImage3d:
+  case BuiltinType::OCLEvent:
   case BuiltinType::BuiltinFn:
     return TST_unspecified;
   }
diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 37df4b3..264d075 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -426,6 +426,9 @@ llvm::DIType CGDebugInfo::CreateType(const BuiltinType *BT) {
   case BuiltinType::OCLImage3d:
     return getOrCreateStructPtrType("opencl_image3d_t",
                                     OCLImage3dDITy);
+  case BuiltinType::OCLEvent:
+    return getOrCreateStructPtrType("opencl_event_t",
+                                    OCLEventDITy);
 
   case BuiltinType::UChar:
   case BuiltinType::Char_U: Encoding = llvm::dwarf::DW_ATE_unsigned_char; break;
diff --git a/clang/lib/CodeGen/CGDebugInfo.h b/clang/lib/CodeGen/CGDebugInfo.h
index 3ecf2ed..fbbee0b 100644
--- a/clang/lib/CodeGen/CGDebugInfo.h
+++ b/clang/lib/CodeGen/CGDebugInfo.h
@@ -55,6 +55,7 @@ class CGDebugInfo {
   llvm::DIType OCLImage1dDITy, OCLImage1dArrayDITy, OCLImage1dBufferDITy;
   llvm::DIType OCLImage2dDITy, OCLImage2dArrayDITy;
   llvm::DIType OCLImage3dDITy;
+  llvm::DIType OCLEventDITy;
   
   /// TypeCache - Cache of previously constructed Types.
   llvm::DenseMap<void *, llvm::WeakVH> TypeCache;
diff --git a/clang/lib/CodeGen/CGExpr.cpp b/clang/lib/CodeGen/CGExpr.cpp
index cdbd6e7..9bef08b 100644
--- a/clang/lib/CodeGen/CGExpr.cpp
+++ b/clang/lib/CodeGen/CGExpr.cpp
@@ -2639,6 +2639,8 @@ LValue CodeGenFunction::EmitCastLValue(const CastExpr *E) {
                                            ConvertType(ToType));
     return MakeAddrLValue(V, E->getType());
   }
+  case CK_ZeroToOCLEvent:
+    llvm_unreachable("NULL to OpenCL event lvalue cast is not valid");
   }
   
   llvm_unreachable("Unhandled lvalue cast kind?");
diff --git a/clang/lib/CodeGen/CGExprAgg.cpp b/clang/lib/CodeGen/CGExprAgg.cpp
index b037113..a35ef0c 100644
--- a/clang/lib/CodeGen/CGExprAgg.cpp
+++ b/clang/lib/CodeGen/CGExprAgg.cpp
@@ -648,6 +648,7 @@ void AggExprEmitter::VisitCastExpr(CastExpr *E) {
   case CK_ARCExtendBlockObject:
   case CK_CopyAndAutoreleaseBlockObject:
   case CK_BuiltinFnToFnPtr:
+  case CK_ZeroToOCLEvent:
     llvm_unreachable("cast kind invalid for aggregate types");
   }
 }
diff --git a/clang/lib/CodeGen/CGExprComplex.cpp b/clang/lib/CodeGen/CGExprComplex.cpp
index 1270297..0a53d4f 100644
--- a/clang/lib/CodeGen/CGExprComplex.cpp
+++ b/clang/lib/CodeGen/CGExprComplex.cpp
@@ -428,6 +428,7 @@ ComplexPairTy ComplexExprEmitter::EmitCast(CastExpr::CastKind CK, Expr *Op,
   case CK_ARCExtendBlockObject:
   case CK_CopyAndAutoreleaseBlockObject:
   case CK_BuiltinFnToFnPtr:
+  case CK_ZeroToOCLEvent:
     llvm_unreachable("invalid cast kind for complex value");
 
   case CK_FloatingRealToComplex:
diff --git a/clang/lib/CodeGen/CGExprConstant.cpp b/clang/lib/CodeGen/CGExprConstant.cpp
index 2c107cb..80ab2ed 100644
--- a/clang/lib/CodeGen/CGExprConstant.cpp
+++ b/clang/lib/CodeGen/CGExprConstant.cpp
@@ -747,6 +747,7 @@ public:
     case CK_FloatingToIntegral:
     case CK_FloatingToBoolean:
     case CK_FloatingCast:
+    case CK_ZeroToOCLEvent:
       return 0;
     }
     llvm_unreachable("Invalid CastKind");
diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
index 5715913..ed927e2 100644
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -1383,6 +1383,11 @@ Value *ScalarExprEmitter::VisitCastExpr(CastExpr *CE) {
     return EmitComplexToScalarConversion(V, E->getType(), DestTy);
   }
 
+  case CK_ZeroToOCLEvent: {
+    assert(DestTy->isEventT() && "CK_ZeroToOCLEvent cast on non event type");
+    return llvm::Constant::getNullValue(ConvertType(DestTy));
+  }
+
   }
 
   llvm_unreachable("unknown scalar cast");
diff --git a/clang/lib/CodeGen/CGOpenCLRuntime.cpp b/clang/lib/CodeGen/CGOpenCLRuntime.cpp
index bb239c6..215d096 100644
--- a/clang/lib/CodeGen/CGOpenCLRuntime.cpp
+++ b/clang/lib/CodeGen/CGOpenCLRuntime.cpp
@@ -55,5 +55,8 @@ llvm::Type *CGOpenCLRuntime::convertOpenCLSpecificType(const Type *T) {
   case BuiltinType::OCLImage3d:
     return llvm::PointerType::get(llvm::StructType::create(
                            CGM.getLLVMContext(), "opencl.image3d_t"), 0);
+  case BuiltinType::OCLEvent:
+    return llvm::PointerType::get(llvm::StructType::create(
+                           CGM.getLLVMContext(), "opencl.event_t"), 0);
   }
 }
diff --git a/clang/lib/CodeGen/CGRTTI.cpp b/clang/lib/CodeGen/CGRTTI.cpp
index 41b73e23..3d65892 100644
--- a/clang/lib/CodeGen/CGRTTI.cpp
+++ b/clang/lib/CodeGen/CGRTTI.cpp
@@ -197,6 +197,7 @@ static bool TypeInfoIsInStandardLibrary(const BuiltinType *Ty) {
     case BuiltinType::OCLImage2d:
     case BuiltinType::OCLImage2dArray:
     case BuiltinType::OCLImage3d:
+    case BuiltinType::OCLEvent:
       return true;
       
     case BuiltinType::Dependent:
diff --git a/clang/lib/CodeGen/CodeGenTypes.cpp b/clang/lib/CodeGen/CodeGenTypes.cpp
index 2c5f2d8..c186ebff 100644
--- a/clang/lib/CodeGen/CodeGenTypes.cpp
+++ b/clang/lib/CodeGen/CodeGenTypes.cpp
@@ -374,6 +374,7 @@ llvm::Type *CodeGenTypes::ConvertType(QualType T) {
     case BuiltinType::OCLImage2d:
     case BuiltinType::OCLImage2dArray:
     case BuiltinType::OCLImage3d:
+    case BuiltinType::OCLEvent:
       ResultType = CGM.getOpenCLRuntime().convertOpenCLSpecificType(Ty);
       break;
     
diff --git a/clang/lib/Edit/RewriteObjCFoundationAPI.cpp b/clang/lib/Edit/RewriteObjCFoundationAPI.cpp
index 312c86f..215aacd 100644
--- a/clang/lib/Edit/RewriteObjCFoundationAPI.cpp
+++ b/clang/lib/Edit/RewriteObjCFoundationAPI.cpp
@@ -1075,6 +1075,7 @@ static bool rewriteToNumericBoxedExpression(const ObjCMessageExpr *Msg,
     case CK_NonAtomicToAtomic:
     case CK_CopyAndAutoreleaseBlockObject:
     case CK_BuiltinFnToFnPtr:
+    case CK_ZeroToOCLEvent:
       return false;
     }
   }
diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index f9c68c7..cfe5d1b 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -2783,6 +2783,10 @@ void Parser::ParseDeclarationSpecifiers(DeclSpec &DS,
       isInvalid = DS.SetTypeSpecType(DeclSpec::TST_image3d_t, Loc,
                                      PrevSpec, DiagID);
       break;
+    case tok::kw_event_t:
+      isInvalid = DS.SetTypeSpecType(DeclSpec::TST_event_t, Loc,
+                                     PrevSpec, DiagID);
+      break;
     case tok::kw___unknown_anytype:
       isInvalid = DS.SetTypeSpecType(TST_unknown_anytype, Loc,
                                      PrevSpec, DiagID);
@@ -3633,6 +3637,7 @@ bool Parser::isKnownToBeTypeSpecifier(const Token &Tok) const {
   case tok::kw_image2d_t:
   case tok::kw_image2d_array_t:
   case tok::kw_image3d_t:
+  case tok::kw_event_t:
 
     // struct-or-union-specifier (C99) or class-specifier (C++)
   case tok::kw_class:
@@ -3713,6 +3718,7 @@ bool Parser::isTypeSpecifierQualifier() {
   case tok::kw_image2d_t:
   case tok::kw_image2d_array_t:
   case tok::kw_image3d_t:
+  case tok::kw_event_t:
 
     // struct-or-union-specifier (C99) or class-specifier (C++)
   case tok::kw_class:
@@ -3865,6 +3871,7 @@ bool Parser::isDeclarationSpecifier(bool DisambiguatingWithExpression) {
   case tok::kw_image2d_t:
   case tok::kw_image2d_array_t:
   case tok::kw_image3d_t:
+  case tok::kw_event_t:
 
     // struct-or-union-specifier (C99) or class-specifier (C++)
   case tok::kw_class:
diff --git a/clang/lib/Parse/ParseExpr.cpp b/clang/lib/Parse/ParseExpr.cpp
index d6d38c7..9c788a1 100644
--- a/clang/lib/Parse/ParseExpr.cpp
+++ b/clang/lib/Parse/ParseExpr.cpp
@@ -1024,6 +1024,7 @@ ExprResult Parser::ParseCastExpression(bool isUnaryExpression,
   case tok::kw_image2d_t:
   case tok::kw_image2d_array_t:
   case tok::kw_image3d_t: {
+  case tok::kw_event_t:
     if (!getLangOpts().CPlusPlus) {
       Diag(Tok, diag::err_expected_expression);
       return ExprError();
diff --git a/clang/lib/Parse/ParseTentative.cpp b/clang/lib/Parse/ParseTentative.cpp
index 78d73bc..1116daa 100644
--- a/clang/lib/Parse/ParseTentative.cpp
+++ b/clang/lib/Parse/ParseTentative.cpp
@@ -843,6 +843,7 @@ Parser::isExpressionOrTypeSpecifierSimple(tok::TokenKind Kind) {
   case tok::kw_image2d_t:
   case tok::kw_image2d_array_t:
   case tok::kw_image3d_t:
+  case tok::kw_event_t:
   case tok::kw___unknown_anytype:
     return TPResult::False();
 
diff --git a/clang/lib/Sema/DeclSpec.cpp b/clang/lib/Sema/DeclSpec.cpp
index 35b07361..6d30b89 100644
--- a/clang/lib/Sema/DeclSpec.cpp
+++ b/clang/lib/Sema/DeclSpec.cpp
@@ -286,6 +286,7 @@ bool Declarator::isDeclarationOfFunction() const {
     case TST_image2d_t:
     case TST_image2d_array_t:
     case TST_image3d_t:
+    case TST_event_t:
       return false;
 
     case TST_decltype:
@@ -427,6 +428,7 @@ const char *DeclSpec::getSpecifierName(DeclSpec::TST T) {
   case DeclSpec::TST_image2d_t:   return "image2d_t";
   case DeclSpec::TST_image2d_array_t: return "image2d_array_t";
   case DeclSpec::TST_image3d_t:   return "image3d_t";
+  case DeclSpec::TST_event_t:     return "event_t";
   case DeclSpec::TST_error:       return "(error)";
   }
   llvm_unreachable("Unknown typespec!");
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index dbdbc3d..7936efa1 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -4401,6 +4401,22 @@ Sema::ActOnVariableDeclarator(Scope *S, Declarator &D, DeclContext *DC,
       SC = SC_OpenCLWorkGroupLocal;
       SCAsWritten = SC_OpenCLWorkGroupLocal;
     }
+
+    // OpenCL 1.2 spec, p6.9 r:
+    // The event type cannot be used to declare a program scope variable.
+    // The event type cannot be used with the __local, __constant and __global
+    // address space qualifiers.
+    if (R->isEventT()) {
+      if (S->getParent() == 0) {
+        Diag(D.getLocStart(), diag::err_event_t_global_var);
+        D.setInvalidType();
+      }
+
+      if (R.getAddressSpace()) {
+        Diag(D.getLocStart(), diag::err_event_t_addr_space_qual);
+        D.setInvalidType();
+      }
+    }
   }
 
   bool isExplicitSpecialization = false;
@@ -6136,12 +6152,26 @@ Sema::ActOnFunctionDeclarator(Scope *S, Declarator &D, DeclContext *DC,
     }
   }
 
-  // OpenCL v1.2 s6.8 static is invalid for kernel functions.
-  if ((getLangOpts().OpenCLVersion >= 120)
-      && NewFD->hasAttr<OpenCLKernelAttr>()
-      && (SC == SC_Static)) {
-    Diag(D.getIdentifierLoc(), diag::err_static_kernel);
-    D.setInvalidType();
+  if (NewFD->hasAttr<OpenCLKernelAttr>()) {
+
+    // OpenCL v1.2 s6.8 static is invalid for kernel functions.
+    if ((getLangOpts().OpenCLVersion >= 120)
+        && (SC == SC_Static)) {
+      Diag(D.getIdentifierLoc(), diag::err_static_kernel);
+      D.setInvalidType();
+    }
+
+    // OpenCL v1.2 s6.8 n:
+    // Arguments to kernel functions in a program cannot be declared to be of
+    // type event_t.
+    for (FunctionDecl::param_iterator PI = NewFD->param_begin(),
+         PE = NewFD->param_end(); PI != PE; ++PI) {
+      if ((*PI)->getType()->isEventT()) {
+        Diag((*PI)->getLocation(), diag::err_event_t_kernel_arg);
+        D.setInvalidType();
+      }
+    }
+    
   }
 
   MarkUnusedFileScopedDecl(NewFD);
@@ -9776,6 +9806,14 @@ FieldDecl *Sema::HandleField(Scope *S, RecordDecl *Record,
     }
   }
 
+  // OpenCL 1.2 spec, s6.9 r:
+  // The event type cannot be used to declare a structure or union field.
+  if (LangOpts.OpenCL && T->isEventT()) {
+    Diag(Loc, diag::err_event_t_struct_field);
+    D.setInvalidType();
+  }
+
+
   DiagnoseFunctionSpecifiers(D);
 
   if (D.getDeclSpec().isThreadSpecified())
diff --git a/clang/lib/Sema/SemaInit.cpp b/clang/lib/Sema/SemaInit.cpp
index 26bb6ef..e661110 100644
--- a/clang/lib/Sema/SemaInit.cpp
+++ b/clang/lib/Sema/SemaInit.cpp
@@ -2424,6 +2424,7 @@ void InitializationSequence::Step::Destroy() {
   case SK_PassByIndirectRestore:
   case SK_ProduceObjCObject:
   case SK_StdInitializerList:
+  case SK_OCLZeroEvent:
     break;
 
   case SK_ConversionSequence:
@@ -2652,6 +2653,13 @@ void InitializationSequence::AddStdInitializerListConstructionStep(QualType T) {
   Steps.push_back(S);
 }
 
+void InitializationSequence::AddOCLZeroEventStep(QualType T) {
+  Step S;
+  S.Kind = SK_OCLZeroEvent;
+  S.Type = T;
+  Steps.push_back(S);
+}
+
 void InitializationSequence::RewrapReferenceInitList(QualType T,
                                                      InitListExpr *Syntactic) {
   assert(Syntactic->getNumInits() == 1 &&
@@ -4009,6 +4017,27 @@ static bool tryObjCWritebackConversion(Sema &S,
   return true;
 }
 
+//
+// OpenCL 1.2 spec, s6.12.10
+//
+// The event argument can also be used to associate the
+// async_work_group_copy with a previous async copy allowing
+// an event to be shared by multiple async copies; otherwise
+// event should be zero.
+//
+static bool TryOCLZeroEventInitialization(Sema &S,
+                                          InitializationSequence &Sequence,
+                                          QualType DestType,
+                                          Expr *Initializer) {
+  if (!S.getLangOpts().OpenCL || !DestType->isEventT() ||
+      !Initializer->isIntegerConstantExpr(S.getASTContext()) ||
+      (Initializer->EvaluateKnownConstInt(S.getASTContext()) != 0))
+    return false;
+
+  Sequence.AddOCLZeroEventStep(DestType);
+  return true;
+}
+
 InitializationSequence::InitializationSequence(Sema &S,
                                                const InitializedEntity &Entity,
                                                const InitializationKind &Kind,
@@ -4152,6 +4181,10 @@ InitializationSequence::InitializationSequence(Sema &S,
       return;
     }
     
+
+    if (TryOCLZeroEventInitialization(S, *this, DestType, Initializer))
+      return;
+
     // Handle initialization in C
     AddCAssignmentStep(DestType);
     MaybeProduceObjCObject(S, *this, Entity);
@@ -4940,7 +4973,8 @@ InitializationSequence::Perform(Sema &S,
   case SK_PassByIndirectCopyRestore:
   case SK_PassByIndirectRestore:
   case SK_ProduceObjCObject:
-  case SK_StdInitializerList: {
+  case SK_StdInitializerList:
+  case SK_OCLZeroEvent: {
     assert(Args.size() == 1);
     CurInit = Args[0];
     if (!CurInit.get()) return ExprError();
@@ -5453,6 +5487,15 @@ InitializationSequence::Perform(Sema &S,
       CurInit = S.Owned(Semantic);
       break;
     }
+    case SK_OCLZeroEvent: {
+      assert(Step->Type->isEventT() && 
+             "Event initialization on non event type.");
+
+      CurInit = S.ImpCastExprToType(CurInit.take(), Step->Type,
+                                    CK_ZeroToOCLEvent,
+                                    CurInit.get()->getValueKind());
+      break;
+    }
     }
   }
 
@@ -6139,6 +6182,10 @@ void InitializationSequence::dump(raw_ostream &OS) const {
     case SK_StdInitializerList:
       OS << "std::initializer_list from initializer list";
       break;
+
+    case SK_OCLZeroEvent:
+      OS << "OpenCL event_t from zero";
+      break;
     }
   }
 }
diff --git a/clang/lib/Sema/SemaTemplateVariadic.cpp b/clang/lib/Sema/SemaTemplateVariadic.cpp
index 6c70320..bb20913 100644
--- a/clang/lib/Sema/SemaTemplateVariadic.cpp
+++ b/clang/lib/Sema/SemaTemplateVariadic.cpp
@@ -737,6 +737,7 @@ bool Sema::containsUnexpandedParameterPacks(Declarator &D) {
   case TST_image2d_t:
   case TST_image2d_array_t:
   case TST_image3d_t:
+  case TST_event_t:
   case TST_error:
     break;
   }
diff --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
index 35816a42..a3b0c45 100644
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -952,6 +952,10 @@ static QualType ConvertDeclSpecToType(TypeProcessingState &state) {
     Result = Context.OCLImage3dTy;
     break;
 
+  case DeclSpec::TST_event_t:
+    Result = Context.OCLEventTy;
+    break;
+
   case DeclSpec::TST_error:
     Result = Context.IntTy;
     declarator.setInvalidType(true);
diff --git a/clang/lib/Serialization/ASTCommon.cpp b/clang/lib/Serialization/ASTCommon.cpp
index bcd8e87..bf1e25a 100644
--- a/clang/lib/Serialization/ASTCommon.cpp
+++ b/clang/lib/Serialization/ASTCommon.cpp
@@ -66,6 +66,7 @@ serialization::TypeIdxFromBuiltin(const BuiltinType *BT) {
   case BuiltinType::OCLImage2d:       ID = PREDEF_TYPE_IMAGE2D_ID;      break;
   case BuiltinType::OCLImage2dArray:  ID = PREDEF_TYPE_IMAGE2D_ARR_ID;  break;
   case BuiltinType::OCLImage3d:       ID = PREDEF_TYPE_IMAGE3D_ID;      break;
+  case BuiltinType::OCLEvent:         ID = PREDEF_TYPE_EVENT_ID;        break;
   case BuiltinType::BuiltinFn:
                                 ID = PREDEF_TYPE_BUILTIN_FN; break;
 
diff --git a/clang/lib/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index c378570..00bae0a 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -4807,6 +4807,7 @@ QualType ASTReader::GetType(TypeID ID) {
     case PREDEF_TYPE_IMAGE2D_ID:    T = Context.OCLImage2dTy;       break;
     case PREDEF_TYPE_IMAGE2D_ARR_ID: T = Context.OCLImage2dArrayTy; break;
     case PREDEF_TYPE_IMAGE3D_ID:    T = Context.OCLImage3dTy;       break;
+    case PREDEF_TYPE_EVENT_ID:      T = Context.OCLEventTy;         break;
     case PREDEF_TYPE_AUTO_DEDUCT:   T = Context.getAutoDeductType(); break;
         
     case PREDEF_TYPE_AUTO_RREF_DEDUCT: 
diff --git a/clang/lib/StaticAnalyzer/Core/ExprEngineC.cpp b/clang/lib/StaticAnalyzer/Core/ExprEngineC.cpp
index f1ef0f6..ea2fc3c 100644
--- a/clang/lib/StaticAnalyzer/Core/ExprEngineC.cpp
+++ b/clang/lib/StaticAnalyzer/Core/ExprEngineC.cpp
@@ -306,7 +306,8 @@ void ExprEngine::VisitCast(const CastExpr *CastE, const Expr *Ex,
       case CK_CPointerToObjCPointerCast:
       case CK_BlockPointerToObjCPointerCast:
       case CK_AnyPointerToBlockPointerCast:  
-      case CK_ObjCObjectLValueCast: {
+      case CK_ObjCObjectLValueCast: 
+      case CK_ZeroToOCLEvent: {
         // Delegate to SValBuilder to process.
         SVal V = state->getSVal(Ex, LCtx);
         V = svalBuilder.evalCast(V, T, ExTy);