[llvm] [AMDGPU] Remove redundant s_cmp_* after add X, 1 (PR #176962)

[Matt Arsenault via llvm-commits]

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@@ -2300,10 +2299,9 @@ body:             |
   ; GCN-NEXT: bb.2:
   ; GCN-NEXT:   S_ENDPGM 0
   bb.0:
-    successors: %bb.1(0x40000000), %bb.2(0x40000000)
-    liveins: $sgpr0_sgpr1, $vgpr0_vgpr1
-    %0:vgpr_32 = IMPLICIT_DEF
-    %2:sreg_32 = COPY %0
+    successors: %bb.1, %bb.2
+    liveins: $sgpr0
+    %2:sreg_32 = COPY $sgpr0
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arsenm wrote:

Should compact register numbers, so this would be %0

https://github.com/llvm/llvm-project/pull/176962