[llvm] [AMDGPU] Verify dominance when rewriting spills to registers (PR #167347)

[Austin Kerbow via llvm-commits]

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+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx950 -O3 -o - %s | FileCheck %s
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kerbowa wrote:

This testcase started passing incidentally after e95f6fa123d. There is an additional failure somewhere else with the same crash signature, "Virtual register defs don't dominate all uses.", that Harhsa was trying to reduce. Seems like no luck there. I will probably need to create a unit test. See SWDEV-564578 for details.

https://github.com/llvm/llvm-project/pull/167347