[SYCL] Add SYCL device compilation flow.

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

Author: vladimirlaz

clang/include/clang/Basic/LangOptions.def

@@ -215,6 +215,7 @@ LANGOPT(CUDAHostDeviceConstexpr, 1, 1, "treating unattributed constexpr function
 LANGOPT(CUDADeviceApproxTranscendentals, 1, 0, "using approximate transcendental functions")
 LANGOPT(GPURelocatableDeviceCode, 1, 0, "generate relocatable device code")
 
+LANGOPT(SYCL              , 1, 0, "Generate code for SYCL device")
 LANGOPT(SizedDeallocation , 1, 0, "sized deallocation")
 LANGOPT(AlignedAllocation , 1, 0, "aligned allocation")
 LANGOPT(AlignedAllocationUnavailable, 1, 0, "aligned allocation functions are unavailable")

clang/include/clang/Driver/CC1Options.td

@@ -833,8 +833,14 @@ def fopenmp_is_device : Flag<["-"], "fopenmp-is-device">,
 def fopenmp_host_ir_file_path : Separate<["-"], "fopenmp-host-ir-file-path">,
   HelpText<"Path to the IR file produced by the frontend for the host.">;
 
-} // let Flags = [CC1Option]
+//===----------------------------------------------------------------------===//
+// SYCL Options
+//===----------------------------------------------------------------------===//
 
+def fsycl_is_device : Flag<["-"], "fsycl-is-device">,
+  HelpText<"Generate code for SYCL device.">;
+
+} // let Flags = [CC1Option]
 
 //===----------------------------------------------------------------------===//
 // cc1as-only Options

clang/include/clang/Driver/Options.td

@@ -3122,6 +3122,8 @@ defm stack_arrays : BooleanFFlag<"stack-arrays">, Group<gfortran_Group>;
 defm underscoring : BooleanFFlag<"underscoring">, Group<gfortran_Group>;
 defm whole_file : BooleanFFlag<"whole-file">, Group<gfortran_Group>;
 
+def sycl : Flag<["--"], "sycl">,
+  HelpText<"Compile SYCL kernels for device">;
 
 include "CC1Options.td"
 

clang/lib/Driver/ToolChains/Clang.cpp

@@ -3417,6 +3417,7 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
   bool IsWindowsCygnus = RawTriple.isWindowsCygwinEnvironment();
   bool IsWindowsMSVC = RawTriple.isWindowsMSVCEnvironment();
   bool IsIAMCU = RawTriple.isOSIAMCU();
+  bool IsSYCL = Args.hasArg(options::OPT_sycl);
 
   // Adjust IsWindowsXYZ for CUDA/HIP compilations.  Even when compiling in
   // device mode (i.e., getToolchain().getTriple() is NVPTX/AMDGCN, not
@@ -3465,6 +3466,12 @@ void Clang::ConstructJob(Compilation &C, const JobAction &JA,
     CmdArgs.push_back(Args.MakeArgString(NormalizedTriple));
   }
 
+  if (IsSYCL) {
+    // We want to compile sycl kernels.
+    CmdArgs.push_back("-std=c++11");
+    CmdArgs.push_back("-fsycl-is-device");
+  }
+
   if (IsOpenMPDevice) {
     // We have to pass the triple of the host if compiling for an OpenMP device.
     std::string NormalizedTriple =

clang/lib/Frontend/CompilerInvocation.cpp

@@ -2872,6 +2872,8 @@ static void ParseLangArgs(LangOptions &Opts, ArgList &Args, InputKind IK,
           << Opts.OMPHostIRFile;
   }
 
+  Opts.SYCL = Args.hasArg(options::OPT_fsycl_is_device);
+
   // Set CUDA mode for OpenMP target NVPTX if specified in options
   Opts.OpenMPCUDAMode = Opts.OpenMPIsDevice && T.isNVPTX() &&
                         Args.hasArg(options::OPT_fopenmp_cuda_mode);

clang/lib/Frontend/InitPreprocessor.cpp

@@ -1056,6 +1056,10 @@ static void InitializePredefinedMacros(const TargetInfo &TI,
     Builder.defineMacro("__CLANG_CUDA_APPROX_TRANSCENDENTALS__");
   }
 
+  if (LangOpts.SYCL) {
+    Builder.defineMacro("__SYCL_DEVICE_ONLY__");
+  }
+
   // OpenCL definitions.
   if (LangOpts.OpenCL) {
 #define OPENCLEXT(Ext) \