[llvm] [NFC] New test for untested case in SILowerI1Copies (PR #186127)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,149 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -O1 < %s | FileCheck %s
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arsenm wrote:

Shouldn't need -O1 

https://github.com/llvm/llvm-project/pull/186127