[HLSL] Pass flags to cc1 based on language

[beanz]

Summary

Having the flags only pass through if you're using the dxc-driver means
that the clang driver doesn't work for HLSL, which is undesirable. This
change switches to instead passing flags based on the language mode
similar to how OpenCL does it. This allows the clang driver to be used
for HLSL source files as well.

[python3kgae]

clang/test/Driver/hlsl_no_stdinc.hlsl

2

-target?

[beanz]

Fixing test typo, thanks @python3kgae!

clang/include/clang/Driver/Types.h

#undef TYPE
   bool isHIP(ID Id);
 
   /// isObjC - Is this an "ObjC" input (Obj-C and Obj-C++ sources and headers).
   bool isObjC(ID Id);
 
   /// isOpenCL - Is this an "OpenCL" input.
   bool isOpenCL(ID Id);
 
+  /// isHLSL - Is this an HLSL input.
+  bool isHLSL(ID Id);
+
   /// isSrcFile - Is this a source file, i.e. something that still has to be
   /// preprocessed. The logic behind this is the same that decides if the first
   /// compilation phase is a preprocessing one.
   bool isSrcFile(ID Id);
 
   /// lookupTypeForExtension - Lookup the type to use for the file
   /// extension \p Ext.
   ID lookupTypeForExtension(llvm::StringRef Ext);

clang/lib/Driver/ToolChains/Clang.cpp

const unsigned ForwardedArguments[] = {options::OPT_dxil_validator_version,
                                          options::OPT_I,
                                          options::OPT_S,
                                          options::OPT_O,
                                          options::OPT_emit_llvm,
                                          options::OPT_emit_obj,
                                          options::OPT_disable_llvm_passes,
                                          options::OPT_fnative_half_type,
                                          options::OPT_hlsl_entrypoint};
-
+  if (!types::isHLSL(InputType))
+    return;
   for (const auto &Arg : ForwardedArguments)
     if (const auto *A = Args.getLastArg(Arg))
       A->renderAsInput(Args, CmdArgs);
   // Add the default headers if dxc_no_stdinc is not set.
-  if (!Args.hasArg(options::OPT_dxc_no_stdinc))
+  if (!Args.hasArg(options::OPT_dxc_no_stdinc) &&
+      !Args.hasArg(options::OPT_nostdinc))
     CmdArgs.push_back("-finclude-default-header");
 }
 
 static void RenderARCMigrateToolOptions(const Driver &D, const ArgList &Args,
                                         ArgStringList &CmdArgs) {
   bool ARCMTEnabled = false;
   if (!Args.hasArg(options::OPT_fno_objc_arc, options::OPT_fobjc_arc)) {
     if (const Arg *A = Args.getLastArg(options::OPT_ccc_arcmt_check,
if (A->getOption().matches(options::OPT_mrestrict_it)) {
       CmdArgs.push_back("-arm-default-it");
     }
   }
 
   // Forward -cl options to -cc1
   RenderOpenCLOptions(Args, CmdArgs, InputType);
 
   // Forward hlsl options to -cc1
-  if (C.getDriver().IsDXCMode())
-    RenderHLSLOptions(Args, CmdArgs, InputType);
 
   if (IsHIP) {
     if (Args.hasFlag(options::OPT_fhip_new_launch_api,
                      options::OPT_fno_hip_new_launch_api, true))
       CmdArgs.push_back("-fhip-new-launch-api");
     if (Args.hasFlag(options::OPT_fgpu_allow_device_init,
                      options::OPT_fno_gpu_allow_device_init, false))
       CmdArgs.push_back("-fgpu-allow-device-init");

clang/lib/Driver/Types.cpp

bool types::isHIP(ID Id) {
 
   case TY_HIP:
   case TY_PP_HIP:
   case TY_HIP_DEVICE:
     return true;
   }
 }
 
+bool types::isHLSL(ID Id) { return Id == TY_HLSL; }
+
 bool types::isSrcFile(ID Id) {
   return Id != TY_Object && getPreprocessedType(Id) != TY_INVALID;
 }
 
 types::ID types::lookupTypeForExtension(llvm::StringRef Ext) {
   return llvm::StringSwitch<types::ID>(Ext)
            .Case("c", TY_C)
            .Case("C", TY_CXX)

clang/test/Driver/hlsl_no_stdinc.hlsl

 // RUN: %clang_dxc  -Tlib_6_7 -fcgl -Fo - %s -### 2>&1 | FileCheck %s --check-prefix=STDINC
+// RUN: %clang -target dxil-pc-shadermodel6.3-library -o - %s -### 2>&1 | FileCheck %s --check-prefix=STDINC
 // RUN: %clang_dxc  -Tlib_6_7 -hlsl-no-stdinc -fcgl -Fo - %s -### 2>&1 | FileCheck %s --check-prefix=NOSTDINC
+// RUN: %clang -target dxil-pc-shadermodel6.3-library -nostdinc -o - %s -### 2>&1 | FileCheck %s --check-prefix=NOSTDINC
 
 // RUN: %clang -cc1 -triple dxil-pc-shadermodel6.3-library -x hlsl -ast-dump -o - %s -verify
 
 // Make sure hlsl-no-stdinc is translated into finclude-default-header.
 // STDINC:"-finclude-default-header"
 // NOSTDINC-NOT:"-finclude-default-header"
 
 // Make sure uint not work when finclude-default-header is off.
 // expected-error@+1 {{unknown type name 'uint'}}
 uint a;