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

[Vikash Gupta via llvm-commits]

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@@ -0,0 +1,231 @@
+# 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:

The pipeline is stopped way before VGPR allocation here, as it happens much after SILowerSGPR spills. The -start-before=greedy, here it refers to SGPR greedy allocation, followed by virtRegRewriter & SILOwerSGPRSpill. I feel the change needed would eith to use -sgpr-regalloc option OR use  -start-before=greedy,0 to depict using SGPR allocation.

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