Add clang cc1 option to generate OpenCL builtin functions

[Pierre]

Summary

Clang cc1 currently sets the -finclude-default-header flag by default, including the opencl-c.h header file. This patch adds a -fgenerate-opencl-builtin flag to generate OpenCL builtin functions with Tablegen. This flag overrides the -finclude-default-header flag.

This patch follows https://reviews.llvm.org/D60763

[Anastasia]

clang/include/clang/Driver/CC1Options.td

755

I feel may be it should be -fadd-opencl-builtins just to hide implementation details from the clang users.

Also the description should be something like:

"Add OpenCL builtin function definitions automatically..."

[Pierre]

The name of the command line option has been updated.

[Anastasia]

LGTM! Thanks!

[Pierre]

Forgot to update one argument

[Pierre]

The changes are part of https://reviews.llvm.org/D60763 which was merged.

clang/include/clang/Basic/LangOptions.def

 LANGOPT(CFProtectionBranch , 1, 0, "Control-Flow Branch Protection enabled")
 LANGOPT(FakeAddressSpaceMap , 1, 0, "OpenCL fake address space map")
 ENUM_LANGOPT(AddressSpaceMapMangling , AddrSpaceMapMangling, 2, ASMM_Target, "OpenCL address space map mangling mode")
-LANGOPT(IncludeDefaultHeader, 1, 0, "Include default header file for OpenCL")
+LANGOPT(IncludeDefaultHeader, 1, 0, "Include default header file containing OpenCL builtin functions")
+LANGOPT(AddOpenCLBuiltins, 1, 0, "Add OpenCL builtin function declarations automatically")
 BENIGN_LANGOPT(DelayedTemplateParsing , 1, 0, "delayed template parsing")
 LANGOPT(BlocksRuntimeOptional , 1, 0, "optional blocks runtime")
 LANGOPT(

clang/include/clang/Driver/CC1Options.td

 def fdefault_calling_conv_EQ : Joined<["-"], "fdefault-calling-conv=">,
   HelpText<"Set default calling convention">, Values<"cdecl,fastcall,stdcall,vectorcall,regcall">;
 def finclude_default_header : Flag<["-"], "finclude-default-header">,
-  HelpText<"Include the default header file for OpenCL">;
+  HelpText<"Include default header file containing OpenCL builtin functions">;
+def fadd_opencl_builtins: Flag<["-"], "fadd-opencl-builtins">,
+  HelpText<"Add OpenCL builtin function declarations automatically">;
 def fpreserve_vec3_type : Flag<["-"], "fpreserve-vec3-type">,
   HelpText<"Preserve 3-component vector type">;
 def fwchar_type_EQ : Joined<["-"], "fwchar-type=">,

clang/lib/Frontend/CompilerInvocation.cpp

     Opts.NativeHalfArgsAndReturns = 1;
     Opts.OpenCLCPlusPlus = Opts.CPlusPlus;
     // Include default header file for OpenCL.
-    if (Opts.IncludeDefaultHeader) {
+    if (Opts.IncludeDefaultHeader && !Opts.AddOpenCLBuiltins) {
       PPOpts.Includes.push_back("opencl-c.h");
     }
   }

   }
 
   Opts.IncludeDefaultHeader = Args.hasArg(OPT_finclude_default_header);
+  Opts.AddOpenCLBuiltins = Args.hasArg(OPT_fadd_opencl_builtins);
 
   llvm::Triple T(TargetOpts.Triple);
   CompilerInvocation::setLangDefaults(Opts, IK, T, PPOpts, LangStd);

clang/lib/Sema/SemaLookup.cpp

       }
 
       // Check if this is an OpenCL Builtin, and if so, insert the declarations.
-      if (S.getLangOpts().OpenCL) {
+      if (S.getLangOpts().OpenCL && S.getLangOpts().AddOpenCLBuiltins) {
         auto Index = isOpenCLBuiltin(II->getName());
         if (Index.first) {
           InsertBuiltinDeclarations(S, R, II, Index.first, Index.second);