[llvm] [GlobalISel] Combine away G_UNMERGE(G_IMPLICITDEF). (PR #119183)

[Thorsten Schütt via llvm-commits]

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@@ -22,8 +22,8 @@ body: |
 
     ; CHECK-LABEL: name: test_implicit_def_s3
     ; CHECK: [[DEF:%[0-9]+]]:_(s64) = G_IMPLICIT_DEF
-    ; CHECK: [[SEXT_INREG:%[0-9]+]]:_(s64) = G_SEXT_INREG [[DEF]], 3
-    ; CHECK: $x0 = COPY [[SEXT_INREG]](s64)
+    ; CHECK-NEXT: [[SEXT_INREG:%[0-9]+]]:_(s64) = G_SEXT_INREG [[DEF]], 3
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tschuett wrote:

G_SEXT_INREG of undef.

https://github.com/llvm/llvm-project/pull/119183