[llvm] [AMDGPU] Replace dynamic VGPR feature with attribute (PR #133444)

[Diana Picus via llvm-commits]

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@@ -199,8 +199,13 @@ unsigned getMaxVGPRs(const TargetMachine &TM, const Function &F) {
   if (!TM.getTargetTriple().isAMDGCN())
     return 128;
 
+  bool IsDynamicVGPR = false;
+  if (F.hasFnAttribute("amdgpu-dynamic-vgpr"))
+    IsDynamicVGPR = F.getFnAttribute("amdgpu-dynamic-vgpr").getValueAsBool();
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rovka wrote:

I'm thinking of adding a helper for this somewhere, but I'm not sure what would be a good place. Any suggestions?

https://github.com/llvm/llvm-project/pull/133444