[llvm] [AMDGPU] Cgscc amdgpu attributor (PR #179719)

[Matt Arsenault via llvm-commits]

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@@ -923,6 +857,16 @@ void AMDGPUTargetMachine::registerPassBuilderCallbacks(PassBuilder &PB) {
 #define GET_PASS_REGISTRY "AMDGPUPassRegistry.def"
 #include "llvm/Passes/TargetPassRegistry.inc"
 
+  PB.registerPipelineParsingCallback(
+      [this](StringRef Name, CGSCCPassManager &PM,
+             ArrayRef<PassBuilder::PipelineElement> Pipeline) {
+        if (Name == "amdgpu-attributor-cgscc") {
+          PM.addPass(AMDGPUAttributorCGSCCPass(*this));
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arsenm wrote:

This shouldn't be run for R600, it should be safe to cast it 

https://github.com/llvm/llvm-project/pull/179719