[OpenCL] Add function name to extension diagnostic

[joey]

Summary

Slightly improve the diagnostic by including the function name.

This has been separated out from https://reviews.llvm.org/D33945.

[bader]

LGTM.
Just one minor comment.
Thanks.

clang/Sema/Sema.h

8435

I think it's better to use NamedDecl to allow this function be used for declarations other than FunctionDecl.

[joey]

Thanks!

Making that change, going to re-run the tests and then I'll commit.

Sema/Sema.cpp

   if (checkOpenCLDisabledTypeOrDecl(Decl, Loc, QT, OpenCLDeclExtMap))
     return true;
 
   // Check extensions for builtin types.
   return checkOpenCLDisabledTypeOrDecl(QT.getCanonicalType().getTypePtr(), Loc,
                                        QT, OpenCLTypeExtMap);
 }
 
-bool Sema::checkOpenCLDisabledDecl(const Decl &D, const Expr &E) {
-  return checkOpenCLDisabledTypeOrDecl(&D, E.getLocStart(), "",
+bool Sema::checkOpenCLDisabledDecl(const FunctionDecl &D, const Expr &E) {
+  IdentifierInfo *FnName = D.getIdentifier();
+  return checkOpenCLDisabledTypeOrDecl(&D, E.getLocStart(), FnName,
                                        OpenCLDeclExtMap, 1, D.getSourceRange());
 }

SemaOpenCL/extension-begin.cl

 }
 
 #pragma OPENCL EXTENSION my_ext : disable 
 void test_f2(void) {
   struct A test_A2; // expected-error {{use of type 'struct A' requires my_ext extension to be enabled}}
   const struct A test_A_local; // expected-error {{use of type 'struct A' requires my_ext extension to be enabled}}
   TypedefOfA test_typedef_A; // expected-error {{use of type 'TypedefOfA' (aka 'struct A') requires my_ext extension to be enabled}}
   PointerOfA test_A_pointer; // expected-error {{use of type 'PointerOfA' (aka 'const struct A *') requires my_ext extension to be enabled}}
-  f(); // expected-error {{use of declaration requires my_ext extension to be enabled}}
+  f(); // expected-error {{use of declaration 'f' requires my_ext extension to be enabled}}
   g(0); // expected-error {{no matching function for call to 'g'}}
         // expected-note@-26 {{candidate disabled due to OpenCL extension}}
         // expected-note@-22 {{candidate function not viable: requires 0 arguments, but 1 was provided}}
 }
 
 #endif // HEADER_USER
 

clang/Basic/DiagnosticSemaKinds.td

 def err_opencl_type_can_only_be_used_as_function_parameter : Error <
   "type %0 can only be used as a function parameter in OpenCL">;
 def warn_opencl_attr_deprecated_ignored : Warning <
   "%0 attribute is deprecated and ignored in OpenCL version %1">,
   InGroup<IgnoredAttributes>;
 def err_opencl_variadic_function : Error<
   "invalid prototype, variadic arguments are not allowed in OpenCL">;
 def err_opencl_requires_extension : Error<
-  "use of %select{type |declaration}0%1 requires %2 extension to be enabled">;
+  "use of %select{type|declaration}0 %1 requires %2 extension to be enabled">;
 
 // OpenCL v2.0 s6.13.6 -- Builtin Pipe Functions
 def err_opencl_builtin_pipe_first_arg : Error<
   "first argument to %0 must be a pipe type">;
 def err_opencl_builtin_pipe_arg_num : Error<
   "invalid number of arguments to function: %0">;
 def err_opencl_builtin_pipe_invalid_arg : Error<
   "invalid argument type to function %0 (expecting %1 having %2)">;

clang/Sema/Sema.h

   /// emit diagnostics.
   /// \return true if type is disabled.
   bool checkOpenCLDisabledTypeDeclSpec(const DeclSpec &DS, QualType T);
 
   /// \brief Check if declaration \p D used by expression \p E
   /// is disabled due to required OpenCL extensions being disabled. If so,
   /// emit diagnostics.
   /// \return true if type is disabled.
-  bool checkOpenCLDisabledDecl(const Decl &D, const Expr &E);
+  bool checkOpenCLDisabledDecl(const FunctionDecl &D, const Expr &E);
 
   //===--------------------------------------------------------------------===//
   // OpenMP directives and clauses.
   //
 private:
   void *VarDataSharingAttributesStack;
   /// Set to true inside '#pragma omp declare target' region.
   bool IsInOpenMPDeclareTargetContext = false;