[llvm] [AMDGPU] In instruction selector, allow copy from physical reg to s1 (PR #96157)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,138 @@
+# RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -run-pass=instruction-select -verify-machineinstrs -o - %s | FileCheck -check-prefix=WAVE64 %s
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arsenm wrote:

```suggestion
# RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -run-pass=instruction-select -o - %s | FileCheck -check-prefix=WAVE64 %s
```

https://github.com/llvm/llvm-project/pull/96157