[llvm] AMDGPU: Handle folding frame indexes into s_add_i32 (PR #101694)

[Diana Picus via llvm-commits]

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@@ -312,27 +304,31 @@ body:             |
     ; MUBUFW64-LABEL: name: s_add_i32__fi_offset0__sgpr
     ; MUBUFW64: liveins: $sgpr8
     ; MUBUFW64-NEXT: {{  $}}
-    ; MUBUFW64-NEXT: $sgpr4 = S_LSHR_B32 $sgpr32, 6, implicit-def dead $scc
-    ; MUBUFW64-NEXT: renamable $sgpr7 = S_ADD_I32 killed $sgpr4, $sgpr8, implicit-def dead $scc
+    ; MUBUFW64-NEXT: renamable $sgpr4 = S_LSHR_B32 $sgpr32, 6, implicit-def dead $scc
+    ; MUBUFW64-NEXT: renamable $sgpr7 = S_ADD_I32 $sgpr4, $sgpr8, implicit-def dead $scc
+    ; MUBUFW64-NEXT: renamable $sgpr7 = COPY $sgpr8
     ; MUBUFW64-NEXT: SI_RETURN implicit $sgpr7
     ;
     ; MUBUFW32-LABEL: name: s_add_i32__fi_offset0__sgpr
     ; MUBUFW32: liveins: $sgpr8
     ; MUBUFW32-NEXT: {{  $}}
-    ; MUBUFW32-NEXT: $sgpr4 = S_LSHR_B32 $sgpr32, 5, implicit-def dead $scc
-    ; MUBUFW32-NEXT: renamable $sgpr7 = S_ADD_I32 killed $sgpr4, $sgpr8, implicit-def dead $scc
+    ; MUBUFW32-NEXT: renamable $sgpr4 = S_LSHR_B32 $sgpr32, 5, implicit-def dead $scc
+    ; MUBUFW32-NEXT: renamable $sgpr7 = S_ADD_I32 $sgpr4, $sgpr8, implicit-def dead $scc
+    ; MUBUFW32-NEXT: renamable $sgpr7 = COPY $sgpr8
     ; MUBUFW32-NEXT: SI_RETURN implicit $sgpr7
     ;
     ; FLATSCRW64-LABEL: name: s_add_i32__fi_offset0__sgpr
     ; FLATSCRW64: liveins: $sgpr8
     ; FLATSCRW64-NEXT: {{  $}}
     ; FLATSCRW64-NEXT: renamable $sgpr7 = S_ADD_I32 $sgpr32, $sgpr8, implicit-def dead $scc
+    ; FLATSCRW64-NEXT: renamable $sgpr7 = COPY $sgpr8
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rovka wrote:

Why are we overwriting sgpr7 here and in other similar cases in this file?

https://github.com/llvm/llvm-project/pull/101694