[PATCH] D82087: AMDGPU/clang: Add builtins for llvm.amdgcn.ballot

[Matt Arsenault via Phabricator via cfe-commits]

arsenm marked 2 inline comments as done.
arsenm added inline comments.


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Comment at: clang/lib/Basic/Targets/AMDGPU.cpp:288
+  if (!IsNullCPU) {
+    // Default to wave32 if available, or wave64 if not
+    if (Features.count("wavefrontsize32") == 0 &&
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sameerds wrote:
> So the implication here is that wave32 is the preferred choice on newer architectures, and hence the default when available?
Yes, this has always been the case


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Comment at: clang/lib/Basic/Targets/AMDGPU.cpp:293
+        "wavefrontsize32" : "wavefrontsize64";
+      Features.insert(std::make_pair(DefaultWaveSizeFeature, true));
+    }
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yaxunl wrote:
> what's the default wave front size in backend for gfx10* before this change?
It's always been wave32


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D82087/new/

https://reviews.llvm.org/D82087