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

[via llvm-commits]

anupkum-sgs wrote:

I’d keep a local copy in both files rather than promoting this to TargetInstrInfo (or a shared header).

InstructionStoresToFI is a small, file-static predicate. Putting it on TII makes it a public CodeGen API. Duplicating ~15 lines is cheaper than introducing a public helper for two internal call sites. We can hoist later if a third user turns up.

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