[PATCH] D100945: [GreedyRA] Fix removeBackCopies to account empty copies

[Serguei Katkov via Phabricator via llvm-commits]

skatkov added a comment.

empty copy is introduced by D100748 <https://reviews.llvm.org/D100748> when we skip RegAssign.insert.
When another copy is hoisted after that we can get these two copies.



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Comment at: llvm/test/CodeGen/X86/statepoint-invoke-ra-remove-back-copies.mir:12
+
+  define void @hoge(i8 addrspace(1)* %arg) gc "statepoint-example" personality i32* ()* @widget {
+  bb:
----------------
reames wrote:
> Any chance this can be further reduced?  This looks really fragile.
I did my best to reduce it using bugpoint, this is minimal version.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D100945/new/

https://reviews.llvm.org/D100945