[llvm] [PHIElimination] Verify reappropriated COPY is of similar register class, update livevars. (PR #146337)

[Mikael Holmén via llvm-commits]

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@@ -117,3 +117,54 @@ body: |
 
 ...
 
+---
+name: update_livevars
+tracksRegLiveness: true
+body:             |
+  bb.0:
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mikaelholmen wrote:

Missing CHECKs

https://github.com/llvm/llvm-project/pull/146337