[llvm] [CodeGen] MachineLICM: Do not consider "loop liveins" as loop defs (PR #121769)

[Matt Arsenault via llvm-commits]

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@@ -644,6 +638,16 @@ void MachineLICMImpl::HoistRegionPostRA(MachineLoop *CurLoop,
       ProcessMI(&MI, RUDefs, RUClobbers, StoredFIs, Candidates, CurLoop);
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arsenm wrote:

Processing the loop forward is suspect, physreg liveness tracking should always be done in reverse 

https://github.com/llvm/llvm-project/pull/121769