[llvm] AMDGPU: Fix si-fix-sgpr-copies asserting on VReg_1 phi (PR #128903)

[Christudasan Devadasan via llvm-commits]

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@@ -0,0 +1,97 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
+# RUN: llc -mtriple=amdgcn-mesa-mesa3d -mcpu=gfx900 -run-pass=si-fix-sgpr-copies,si-i1-copies -o - %s | FileCheck %s
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cdevadas wrote:

Wouldn't this case be relevant to compute as well? Asking because of the triple with `mesa`.

https://github.com/llvm/llvm-project/pull/128903