[llvm] [CodeGen] Add MachineRegisterClassInfo analysis pass (PR #120690)

[Pengcheng Wang via llvm-commits]

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@@ -1005,6 +1016,7 @@
 ; GCN-O2-NEXT:        SI lower SGPR spill instructions
 ; GCN-O2-NEXT:        Virtual Register Map
 ; GCN-O2-NEXT:        Live Register Matrix
+; GCN-O2-NEXT:        Machine Register Class Info Analysis
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wangpc-pp wrote:

Can you teach me how to eliminate these recomputations? Or can I land first and can you make a follow-up? I have no idea how to fix this. :-(

https://github.com/llvm/llvm-project/pull/120690