[clang] [llvm] [AMDGPU] Error out in clang if wavefront64 is used on gfx1250 (PR #153693)

[Yaxun Liu via cfe-commits]

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@@ -774,6 +774,18 @@ static bool isWave32Capable(StringRef GPU, const Triple &T) {
   return IsWave32Capable;
 }
 
+static bool isWave64Capable(StringRef GPU, const Triple &T) {
+  if (T.isAMDGCN()) {
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yxsamliu wrote:

I agree with Matt. We already have fillAMDGPUFeatureMap() that is supposed to fill the default features. On line 434/435, it already fills wave32/64 for spirv. It is kind of redundant and may cause inconsistency to have isWave32Capable() and isWave64Capable(). If we need a way to get wave64 capability, we could cache the default target features returned by fillAMDGPUFeatureMap() in TargetInfo and look it up for wave64 capability.

https://github.com/llvm/llvm-project/pull/153693