set opencl_c_version per target, remove CL_3_0_EXTENSIONS

Author: wenju-he

libclc/CMakeLists.txt

@@ -387,21 +387,39 @@ foreach( t ${LIBCLC_TARGETS_TO_BUILD} )
 
     message( STATUS "  device: ${d} ( ${${d}_aliases} )" )
 
-    if ( ARCH STREQUAL spirv OR ARCH STREQUAL spirv64 )
+    # 1.2 is Clang's default OpenCL C language standard to compile for.
+    set( opencl_lang_std "CL1.2" )
+
+    if ( ${DARCH} STREQUAL spirv )
+      set( opencl_lang_std "CL3.0" )
       set( build_flags -O0 -finline-hint-functions -DCLC_SPIRV )
       set( opt_flags )
       set( spvflags --spirv-max-version=1.1 )
       set( MACRO_ARCH SPIRV32 )
       if( ARCH STREQUAL spirv64 )
         set( MACRO_ARCH SPIRV64 )
       endif()
-    elseif( ARCH STREQUAL clspv OR ARCH STREQUAL clspv64 )
+    elseif( ${DARCH} STREQUAL clspv )
+      # Refer to https://github.com/google/clspv for OpenCL version.
+      set( opencl_lang_std "CL3.0" )
       set( build_flags "-Wno-unknown-assumption" -DCLC_CLSPV )
       set( opt_flags -O3 )
       set( MACRO_ARCH CLSPV32 )
       if( ARCH STREQUAL clspv64 )
         set( MACRO_ARCH CLSPV64 )
       endif()
+    elseif( ${DARCH} STREQUAL nvptx )
+      # Refer to https://www.khronos.org/opencl/ for OpenCL version in NV implementation.
+      set( opencl_lang_std "CL3.0" )
+      set( build_flags )
+      set( opt_flags -O3 )
+      set( MACRO_ARCH ${ARCH} )
+    elseif( ${DARCH} STREQUAL amdgcn OR ${DARCH} STREQUAL amdgcn-amdhsa OR ${DARCH} STREQUAL r600 )
+      # Refer to https://github.com/ROCm/clr/tree/develop/opencl for OpenCL version.
+      set( opencl_lang_std "CL2.0" )
+      set( build_flags )
+      set( opt_flags -O3 )
+      set( MACRO_ARCH ${ARCH} )
     else()
       set( build_flags )
       set( opt_flags -O3 )
@@ -411,15 +429,7 @@ foreach( t ${LIBCLC_TARGETS_TO_BUILD} )
     set( LIBCLC_ARCH_OBJFILE_DIR "${LIBCLC_OBJFILE_DIR}/${arch_suffix}" )
     file( MAKE_DIRECTORY ${LIBCLC_ARCH_OBJFILE_DIR} )
 
-    # OpenCL 3.0 extensions
-    string(CONCAT CL_3_0_EXTENSIONS
-      "-cl-ext="
-      "+cl_khr_fp64,"
-      "+cl_khr_fp16,"
-      "+__opencl_c_3d_image_writes,"
-      "+__opencl_c_images,"
-      "+cl_khr_3d_image_writes")
-    list( APPEND build_flags -cl-std=CL3.0 "-Xclang" ${CL_3_0_EXTENSIONS} )
+    list( APPEND build_flags -cl-std=${opencl_lang_std} )
 
     string( TOUPPER "CLC_${MACRO_ARCH}" CLC_TARGET_DEFINE )