[llvm] [LiveRegUnits] Enhanced the register liveness check (PR #66061)

[Matt Arsenault via llvm-commits]

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@@ -7909,7 +7909,7 @@ AArch64InstrInfo::getOutlinableRanges(MachineBasicBlock &MBB,
       CreateNewRangeStartingAt(MI.getIterator());
       continue;
     }
-    LRAvailableEverywhere &= LRU.available(AArch64::LR);
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arsenm wrote:

I think the positive is available check is more readable than having to negate most of the uses 

https://github.com/llvm/llvm-project/pull/66061