[llvm] [AMDGPU][LIT] Added a MIR LIT showing the SGPR spills (PR #94584)

[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
+# RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx908 -verify-machineinstrs -stress-regalloc=3 -start-before=greedy -stop-after=si-lower-sgpr-spills -o - %s | FileCheck -check-prefix=SGPR_SPILLED %s
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vg0204 wrote:

So, I guess this test file need to consider to start from RA rather than post RA else, SCC really won't work thereafter(with optimized SGPR spill code) because of absence of LS , which really gets calculated at RA.

https://github.com/llvm/llvm-project/pull/94584