[clang] [llvm] [mlir] [AMDGPU] Verify AMDGPU required workgroup size matches flat workgroup size (PR #200989)

[Shilei Tian via cfe-commits]

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@@ -2814,6 +2817,80 @@ void Verifier::verifyFunctionMetadata(
   }
 }
 
+void Verifier::verifyAMDGPUReqdWorkGroupSize(const Function &F) {
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shiltian wrote:

I kind of wonder if the generic verifier is the right place doing this kind of check. CC @nikic 

https://github.com/llvm/llvm-project/pull/200989