[SYCL] Add SYCL kernel attribute to clang.

Signed-off-by: Vladimir Lazarev <[email protected]>

Author: vladimirlaz

clang/include/clang/Basic/Attr.td

@@ -991,6 +991,13 @@ def SYCLDevice : InheritableAttr {
   let Documentation = [Undocumented];
 }
 
+def SYCLKernel : InheritableAttr {
+  let Spellings = [GNU<"sycl_kernel">];
+  let Subjects = SubjectList<[Function]>;
+  let LangOpts = [SYCL];
+  let Documentation = [Undocumented];
+}
+
 def C11NoReturn : InheritableAttr {
   let Spellings = [Keyword<"_Noreturn">];
   let Subjects = SubjectList<[Function], ErrorDiag>;

clang/lib/Sema/SemaDeclAttr.cpp

@@ -6280,6 +6280,9 @@ static void ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D,
   case ParsedAttr::AT_Flatten:
     handleSimpleAttribute<FlattenAttr>(S, D, AL);
     break;
+  case ParsedAttr::AT_SYCLKernel:
+    handleSimpleAttribute<SYCLKernelAttr>(S, D, AL);
+    break;
   case ParsedAttr::AT_Format:
     handleFormatAttr(S, D, AL);
     break;

clang/test/Misc/pragma-attribute-supported-attributes-list.test

@@ -117,6 +117,7 @@
 // CHECK-NEXT: ReturnsNonNull (SubjectMatchRule_objc_method, SubjectMatchRule_function)
 // CHECK-NEXT: ReturnsTwice (SubjectMatchRule_function)
 // CHECK-NEXT: SYCLDevice (SubjectMatchRule_function, SubjectMatchRule_variable)
+// CHECK-NEXT: SYCLKernel (SubjectMatchRule_function)
 // CHECK-NEXT: ScopedLockable (SubjectMatchRule_record)
 // CHECK-NEXT: Section (SubjectMatchRule_function, SubjectMatchRule_variable_is_global, SubjectMatchRule_objc_method, SubjectMatchRule_objc_property)
 // CHECK-NEXT: SetTypestate (SubjectMatchRule_function_is_member)

clang/test/SemaSYCL/kernel-attribute.cpp

@@ -0,0 +1,5 @@
+// RUN: %clang_cc1 -fsycl-is-device -fsyntax-only -fcxx-exceptions -verify -pedantic -std=c++11 %s
+// expected-no-diagnostics
+
+__attribute((sycl_kernel)) void foo() {
+}