[PATCH] D105858: opencl-c.h: add 3.0 optional extension support for a few more bits

Mon Jul 19 15:03:43 PDT 2021

Anastasia added inline comments.

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Comment at: clang/lib/Headers/opencl-c-base.h:329
 #endif // defined(__opencl_c_atomic_scope_all_devices)
-#if defined(cl_intel_subgroups) || defined(cl_khr_subgroups)
+#if defined(cl_intel_subgroups) || defined(cl_khr_subgroups) || defined(__opencl_c_subgroups)
   memory_scope_sub_group = __OPENCL_MEMORY_SCOPE_SUB_GROUP
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azabaznov wrote:
> Anastasia wrote:
> > We had a discussion with @azabaznov around features that are aliasing each other and we have discussed to use one feature macro for those. Clang should already ensure that both are set/unset simultaneously? And for those that are not set in clang we can set them correctly here in the header directly.
> > 
> Yeah, I we did. Note that this is applicable to fp64 and 3d image writes, while __openc_c_subgroups and cl_khr_subgroups are not equivalent as extension requires subgroup-independent forward progress but subgroup-independent forward progress is optional in OpenCL C 3.0. I'll try submit a patch for 3d image writes feature macro support this week.
Ok, I see so while the functions are identical they are not entirely equivalent extensions so vendors might support one but not the other? In this case I think we should keep checking both but it would be good to add a comment explaining why we are checking both macros here.

Btw do you happen to have spec reference? I can't find anything relevant.

Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D105858/new/

https://reviews.llvm.org/D105858