[llvm] [AMDGPU] Fix GCUpwardRPTracker. (PR #74328)

[Valery Pykhtin via llvm-commits]

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@@ -666,3 +625,70 @@ body: |
     EXP_DONE 0, %49:vgpr_32, undef %51:vgpr_32, undef %53:vgpr_32, undef %55:vgpr_32, -1, 0, 1, implicit $exec
     S_ENDPGM 0
 ...
+---
+name: early_clobber_def_used_on_rhs
+registers:
+  - { id: 0, class: vgpr_32 }
+body: |
+  ; RPU-LABEL: name: early_clobber_def_used_on_rhs
+  ; RPU: bb.0:
+  ; RPU-NEXT:   Live-in:
+  ; RPU-NEXT:   SGPR  VGPR
+  ; RPU-NEXT:   0     0
+  ; RPU-NEXT:   0     1      dead %3:vgpr_32 = COPY $vgpr0
+  ; RPU-NEXT:   0     0
+  ; RPU-NEXT:   0     1      early-clobber %2:vgpr_32 = COPY %0:vgpr_32
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vpykhtin wrote:

Mir parser renames those registers, I haven't managed to prevent it doing that.

https://github.com/llvm/llvm-project/pull/74328