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

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,108 @@
+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 6
+# RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx90a -O3 -start-before=greedy \
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arsenm wrote:

Probably don't need -O3

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