[SYCL] Use kernel types with the global namespace specifier.

That allows to avoid ambiguity in integration header for kernel
types if namespaces with the same names are defined on different
levels.

Signed-off-by: Vladimir Lazarev <vladimir.lazarev@intel.com>

clang/lib/Sema/SemaSYCL.cpp

@@ -11,6 +11,7 @@
 
 #include "TreeTransform.h"
 #include "clang/AST/AST.h"
+#include "clang/AST/QualTypeNames.h"
 #include "clang/AST/RecordLayout.h"
 #include "clang/AST/RecursiveASTVisitor.h"
 #include "clang/Sema/Sema.h"
@@ -705,7 +706,10 @@ void Sema::ConstructSYCLKernel(FunctionDecl *KernelCallerFunc) {
     // Get Name for our kernel.
     const TemplateArgumentList *TemplateArgs =
         KernelCallerFunc->getTemplateSpecializationArgs();
-    QualType KernelNameType = TemplateArgs->get(0).getAsType();
+    QualType KernelNameType = TypeName::getFullyQualifiedType(
+                                TemplateArgs->get(0).getAsType(),
+                                getASTContext(),
+                                true);
     std::string Name = constructKernelName(KernelNameType);
     populateIntHeader(getSyclIntegrationHeader(), Name, KernelNameType, LE);
 

clang/test/CodeGenSYCL/integration_header.cpp

@@ -14,8 +14,8 @@
 // CHECK: static constexpr
 // CHECK-NEXT: const char* const kernel_names[] = {
 // CHECK-NEXT:   "first_kernel",
-// CHECK-NEXT:   "second_namespace::second_kernel<char>",
-// CHECK-NEXT:   "third_kernel<1, int,  point< X> >"
+// CHECK-NEXT:   "::second_namespace::second_kernel<char>",
+// CHECK-NEXT:   "::third_kernel<1, int,  ::point<X> >"
 // CHECK-NEXT: };
 //
 // CHECK: static constexpr
@@ -27,12 +27,12 @@
 // CHECK-NEXT:   { kernel_param_kind_t::kind_accessor, 2016, 5 },
 // CHECK-NEXT:   { kernel_param_kind_t::kind_scalar, 1, 5 },
 // CHECK-EMPTY:
-// CHECK-NEXT:   //--- second_namespace::second_kernel<char>
+// CHECK-NEXT:   //--- ::second_namespace::second_kernel<char>
 // CHECK-NEXT:   { kernel_param_kind_t::kind_scalar, 4, 0 },
 // CHECK-NEXT:   { kernel_param_kind_t::kind_accessor, 2016, 4 },
 // CHECK-NEXT:   { kernel_param_kind_t::kind_scalar, 1, 4 },
 // CHECK-EMPTY:
-// CHECK-NEXT:   //--- third_kernel<1, int,  point< X> >
+// CHECK-NEXT:   //--- ::third_kernel<1, int, ::point<X> >
 // CHECK-NEXT:   { kernel_param_kind_t::kind_scalar, 4, 0 },
 // CHECK-NEXT:   { kernel_param_kind_t::kind_accessor, 2016, 4 },
 // CHECK-NEXT:   { kernel_param_kind_t::kind_scalar, 1, 4 },
@@ -41,8 +41,8 @@
 //
 // CHECK: template <class KernelNameType> struct KernelInfo;
 // CHECK: template <> struct KernelInfo<class first_kernel> {
-// CHECK: template <> struct KernelInfo<class second_namespace::second_kernel<char>> {
-// CHECK: template <> struct KernelInfo<class third_kernel<1, int, struct point<struct X> >> {
+// CHECK: template <> struct KernelInfo<::second_namespace::second_kernel<char>> {
+// CHECK: template <> struct KernelInfo<::third_kernel<1, int, ::point<X> >> {
 
 namespace cl {
 namespace sycl {