[clang] [libclc] [AMDGPU][libclc] Enable cl_khr_subgroup_non_uniform_arithmetic and use in libclc (PR #200747)

[Matt Arsenault via cfe-commits]

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@@ -324,6 +324,7 @@ class LLVM_LIBRARY_VISIBILITY AMDGPUTargetInfo final : public TargetInfo {
       Opts["cl_khr_mipmap_image"] = true;
       Opts["cl_khr_mipmap_image_writes"] = true;
       Opts["cl_khr_subgroups"] = true;
+      Opts["cl_khr_subgroup_non_uniform_arithmetic"] = true;
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arsenm wrote:

I don't think device-libs implements these functions. This would need to check if the environment is LLVM 

https://github.com/llvm/llvm-project/pull/200747