[llvm] [AMDGPU] Enable GCNRewritePartialRegUses pass by default. (PR #72975)

[Valery Pykhtin via llvm-commits]

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@@ -50,15 +50,17 @@ define amdgpu_ps i128 @extractelement_vgpr_v4i128_sgpr_idx(ptr addrspace(1) %ptr
 ; GFX9-NEXT:    s_set_gpr_idx_on s2, gpr_idx(SRC0)
 ; GFX9-NEXT:    v_mov_b32_e32 v0, v2
 ; GFX9-NEXT:    v_mov_b32_e32 v1, v3
-; GFX9-NEXT:    v_mov_b32_e32 v18, v2
 ; GFX9-NEXT:    s_set_gpr_idx_off
 ; GFX9-NEXT:    v_readfirstlane_b32 s0, v0
+; GFX9-NEXT:    s_set_gpr_idx_on s2, gpr_idx(SRC0)
+; GFX9-NEXT:    v_mov_b32_e32 v0, v2
+; GFX9-NEXT:    s_set_gpr_idx_off
 ; GFX9-NEXT:    v_readfirstlane_b32 s1, v1
 ; GFX9-NEXT:    s_set_gpr_idx_on s2, gpr_idx(SRC0)
-; GFX9-NEXT:    v_mov_b32_e32 v3, v3
+; GFX9-NEXT:    v_mov_b32_e32 v1, v3
 ; GFX9-NEXT:    s_set_gpr_idx_off
-; GFX9-NEXT:    v_readfirstlane_b32 s2, v18
-; GFX9-NEXT:    v_readfirstlane_b32 s3, v3
+; GFX9-NEXT:    v_readfirstlane_b32 s2, v0
+; GFX9-NEXT:    v_readfirstlane_b32 s3, v1
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vpykhtin wrote:

Thank you for the explanation Petar, it's different issue indeed.

https://github.com/llvm/llvm-project/pull/72975