[llvm] [VirtRegMap] Remove unsupported sub-registers during rewrite (PR #201550)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,45 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py UTC_ARGS: --version 6
+; RUN: llc -mcpu=gfx90a -O3 < %s | FileCheck %s
+
+target triple = "amdgcn-amd-amdhsa"
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arsenm wrote:

```suggestion
target triple = "amdgpu9.0a-amd-amdhsa"
```

https://github.com/llvm/llvm-project/pull/201550