[llvm] [MachineLateInstrsCleanup] Reuse redundant spill-slot reloads (PR #220180)

[via llvm-commits]

anupkum-sgs wrote:

I verified that reusing MachineLICM's InstructionStoresToFI is safe here, even though this pass runs after PEI while MachineLICM runs before it. The remaining question is whether to promote the helper into a shared utility (e.g. TargetInstrInfo) and use it in both passes, or keep a local copy in both files. (Analysis done with Claude Opus 5.)

https://github.com/llvm/llvm-project/pull/220180