[OpenCL] Traverse vector types for ocl extensions support

[vmaksimo]

Summary

Given the following kernel:
__kernel void foo()
{

double d;
double4 dd;

}

and cl_khr_fp64 disabled, the compilation would fail due to
the presence of 'double d', but when removed, it passes.

The expectation is that extended vector types of unsupported types
will also be unsupported.

The patch adds the check for this scenario.

[Anastasia]

LGTM! Thanks! Could you please change the commit title tag:
[Sema] -> [OpenCL]

lib/Sema/Sema.cpp

42

It would be better to undo this formatting change. Clang code base seems to be inconsistent on that anyway.

lib/Sema/Sema.cpp

 #include "clang/Sema/TemplateDeduction.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/SmallSet.h"
+
 using namespace clang;
 using namespace sema;
 

   if (auto TagT = dyn_cast<TagType>(QT.getCanonicalType().getTypePtr()))
     Decl = TagT->getDecl();
   auto Loc = DS.getTypeSpecTypeLoc();
+
+  // Check extensions for vector types.
+  // e.g. double4 is not allowed when cl_khr_fp64 is absent.
+  if (QT->isExtVectorType()) {
+    auto TypePtr = QT->castAs<ExtVectorType>()->getElementType().getTypePtr();
+    return checkOpenCLDisabledTypeOrDecl(TypePtr, Loc, QT, OpenCLTypeExtMap);
+  }
+
   if (checkOpenCLDisabledTypeOrDecl(Decl, Loc, QT, OpenCLDeclExtMap))
     return true;
 

test/SemaOpenCL/extensions.cl

 // expected-error@-2{{use of type 'double' requires cl_khr_fp64 extension to be enabled}}
 #endif
 
+  typedef double double4 __attribute__((ext_vector_type(4)));
+  double4 d4 = {0.0f, 2.0f, 3.0f, 1.0f};
+#ifdef NOFP64
+// expected-error@-3 {{use of type 'double' requires cl_khr_fp64 extension to be enabled}}
+// expected-error@-3 {{use of type 'double4' (vector of 4 'double' values) requires cl_khr_fp64 extension to be enabled}}
+#endif
+
   (void) 1.0;
 
 #ifdef NOFP64