[llvm] [AMDGPU][WIP] Optimize SGPR spills (PR #93668)

[Vikash Gupta via llvm-commits]

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+# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 5
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vg0204 wrote:

I believe I added the RUN command for both BEFORE & AFTER stack slot coloring pass (the one invoked just after sgpr regAlloc), & stack indices re-usage can be seen.

https://github.com/llvm/llvm-project/pull/93668