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

[Matt Arsenault via cfe-commits]

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@@ -2814,6 +2817,80 @@ void Verifier::verifyFunctionMetadata(
   }
 }
 
+void Verifier::verifyAMDGPUReqdWorkGroupSize(const Function &F) {
+  if (!TT.isAMDGPU())
+    return;
+
+  MDNode *ReqdWorkGroupSize = F.getMetadata("reqd_work_group_size");
+  if (!ReqdWorkGroupSize)
+    return;
+
+  Check(ReqdWorkGroupSize->getNumOperands() == 3,
+        "reqd_work_group_size must have exactly three operands", &F,
+        ReqdWorkGroupSize);
+  if (ReqdWorkGroupSize->getNumOperands() != 3)
+    return;
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arsenm wrote:

This should be independently verified for the metadata check (which it may already be). This isn't target dependent 

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