[llvm] [GlobalISel] Import samesign flag (second attempt) (PR #114267)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,69 @@
+; NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 4
+; RUN: llc -global-isel -mtriple=aarch64-linux-gnu -O0 -stop-after=irtranslator < %s | FileCheck %s
+
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arsenm wrote:

```suggestion
```

https://github.com/llvm/llvm-project/pull/114267