[OpenCL] Enabling the usage of CLK_NULL_QUEUE as compare operand.

Summary: Enabling the compression of CLK_NULL_QUEUE to variable of type queue_t.

Reviewers: Anastasia

Subscribers: cfe-commits, yaxunl, bader

Differential Revision: https://reviews.llvm.org/D27569

llvm-svn: 290171

1 files changed, 6 insertions, 0 deletions

diff --git a/clang/lib/Sema/SemaOverload.cpp b/clang/lib/Sema/SemaOverload.cpp
index d49142b8d85..c8a45013e9e 100644
--- a/clang/lib/Sema/SemaOverload.cpp
+++ b/clang/lib/Sema/SemaOverload.cpp
@@ -1785,6 +1785,11 @@ static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType,
              From->EvaluateKnownConstInt(S.getASTContext()) == 0) {
     SCS.Second = ICK_Zero_Event_Conversion;
     FromType = ToType;
+  } else if (ToType->isQueueT() &&
+             From->isIntegerConstantExpr(S.getASTContext()) &&
+             (From->EvaluateKnownConstInt(S.getASTContext()) == 0)) {
+    SCS.Second = ICK_Zero_Queue_Conversion;
+    FromType = ToType;
   } else {
     // No second conversion required.
     SCS.Second = ICK_Identity;
@@ -5162,6 +5167,7 @@ static bool CheckConvertedConstantConversions(Sema &S,
   case ICK_Function_Conversion:
   case ICK_Integral_Promotion:
   case ICK_Integral_Conversion: // Narrowing conversions are checked elsewhere.
+  case ICK_Zero_Queue_Conversion:
     return true;
 
   case ICK_Boolean_Conversion: