[OpenCL] Fix parsing of opencl-c.h in CL 3.0

[kpet]

Summary

Ensure that the cl_khr_3d_image_writes pragma is enabled by making
cl_khr_3d_image_writes an optional core feature in CL 3.0 in addition
to being an available extension in 1.0 onwards and a core feature in
CL 2.0.

Signed-off-by: Kevin Petit <[e-mail]>

[Anastasia]

LGTM! Thanks! I would like to hold off committing this for a day or two to see if there is any input from @azabaznov or anyone else.

[kpet]

Thanks! I'll wait for a couple of days before committing then.

[azabaznov]

Thanks for  the patch! Sorry for the delay

Can you please elaborate on what issue you are trying to resolve with this fix? You're trying to emit diagnostics for cl_khr_3d_image_writes for OpenCL C 3.0?

FYI cl_khr_3d_image_writes should have no effect in -cl-ext option for OpenCL C 3.0 as there exist __opencl_c_3d_image_writes,  I think it was discussed in some previous reviews

[kpet]

@azabaznov Without this change, opencl-c.h cannot be parsed with -cl-std=CL3.0 as the write_only image3d_t type is not enabled. The type is currently enabled via cl_khr_3d_image_writes. See https://github.com/llvm/llvm-project/blob/main/clang/include/clang/Basic/OpenCLImageTypes.def#L68. It may be that we want to redesign this such that the type be enabled by the feature macro (or via another mechanism) and have the extension enable the feature macro internally but this would require more thinking and is probably best done as a follow-up IMHO (maybe as part of https://reviews.llvm.org/D92004 or a pre-requisite thereof?).

[azabaznov]

Looks good to me. Thanks!

Without this change, opencl-c.h cannot be parsed with -cl-std=CL3.0 as the write_only image3d_t type is not enabled.

This should be fixed in the following up patches to check for __opencl_c_3d_image_writes feature or either for both: __opencl_c_3d_image_writes and cl_khr_3d_image_writes (in OpenCL C 3.0 mode). But I think it's OK to have this check for now.

[kpet]

Thanks! I'll commit the change.

[kpet]

Committed as https://github.com/llvm/llvm-project/commit/9d25ce743a95a9ad03c0a4b3a705f85c2de52398.

clang/include/clang/Basic/OpenCLExtensions.def

 OPENCL_EXTENSION(cl_khr_fp16, true, 100)
 OPENCL_EXTENSION(cl_khr_int64_base_atomics, true, 100)
 OPENCL_EXTENSION(cl_khr_int64_extended_atomics, true, 100)
-OPENCL_COREFEATURE(cl_khr_3d_image_writes, true, 100, OCL_C_20)
+OPENCL_GENERIC_EXTENSION(cl_khr_3d_image_writes, true, 100, OCL_C_20, OCL_C_30)
 
 // EMBEDDED_PROFILE
 OPENCL_EXTENSION(cles_khr_int64, true, 110)

clang/test/Headers/opencl-c-header.cl

 // RUN: %clang_cc1 -O0 -triple spir-unknown-unknown -internal-isystem ../../lib/Headers -include opencl-c.h -emit-llvm -o - %s -verify -cl-std=CL1.1 | FileCheck %s
 // RUN: %clang_cc1 -O0 -triple spir-unknown-unknown -internal-isystem ../../lib/Headers -include opencl-c.h -emit-llvm -o - %s -verify -cl-std=CL1.2 | FileCheck %s
 // RUN: %clang_cc1 -O0 -triple spir-unknown-unknown -internal-isystem ../../lib/Headers -include opencl-c.h -emit-llvm -o - %s -verify -cl-std=clc++ | FileCheck %s --check-prefix=CHECK20
+// RUN: %clang_cc1 -O0 -triple spir-unknown-unknown -internal-isystem ../../lib/Headers -include opencl-c.h -emit-llvm -o - %s -verify -cl-std=CL3.0 | FileCheck %s
 
 // Test including the default header as a module.
 // The module should be compiled only once and loaded from cache afterwards.

 #endif
 
 // Verify that ATOMIC_VAR_INIT is defined.
-#if defined(__OPENCL_CPP_VERSION__) || (__OPENCL_C_VERSION__ >= CL_VERSION_2_0)
+#if defined(__OPENCL_CPP_VERSION__) || (__OPENCL_C_VERSION__ == CL_VERSION_2_0)
 global atomic_int z = ATOMIC_VAR_INIT(99);
 #endif //__OPENCL_C_VERSION__
 // CHECK-MOD: Reading modules

clang/test/SemaOpenCL/extension-version.cl

 // expected-warning@-2{{OpenCL extension 'cl_khr_fp64' is core feature or supported optional core feature - ignoring}}
 #endif
 
-//Core feature in CL 2.0
+//Core feature in CL 2.0, optional core feature in CL 3.0
 #ifndef cl_khr_3d_image_writes
 #error "Missing cl_khr_3d_image_writes define"
 #endif
 #pragma OPENCL EXTENSION cl_khr_3d_image_writes : enable
-#if (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ == 200) && defined TEST_CORE_FEATURES
+#if (defined(__OPENCL_CPP_VERSION__) || __OPENCL_C_VERSION__ == 200 || __OPENCL_C_VERSION__ == 300) && defined TEST_CORE_FEATURES
 // expected-warning@-2{{OpenCL extension 'cl_khr_3d_image_writes' is core feature or supported optional core feature - ignoring}}
 #endif