[llvm] [AMDGPU] Remove wavefrontsize feature from GFX10+ (PR #98400)

[Matt Arsenault via llvm-commits]

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@@ -105,6 +105,14 @@ GCNSubtarget::initializeSubtargetDependencies(const Triple &TT,
                                         : AMDGPUSubtarget::SOUTHERN_ISLANDS;
   }
 
+  if (!hasFeature(AMDGPU::FeatureWavefrontSize32) &&
+      !hasFeature(AMDGPU::FeatureWavefrontSize64)) {
+    if (getGeneration() >= AMDGPUSubtarget::GFX10)
+      ToggleFeature(AMDGPU::FeatureWavefrontSize32);
+    else
+      ToggleFeature(AMDGPU::FeatureWavefrontSize64);
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arsenm wrote:

I mean if there's a SupportsWave32 feature, implied by FeatureWavefrontSize32, if you specify wavefrontsize32 to a wave64-only target, the incompatible feature check in the parsing logic will hit and it will assume you specified an invalid target and unset the target-cpu.

https://github.com/llvm/llvm-project/pull/98400