[llvm] [CodeGen][MachineLICM] Use RegUnits in HoistRegionPostRA (PR #94608)

[Matt Arsenault via llvm-commits]

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@@ -460,16 +475,18 @@ void MachineLICMBase::ProcessMI(MachineInstr *MI, BitVector &PhysRegDefs,
     assert(Reg.isPhysical() && "Not expecting virtual register!");
 
     if (!MO.isDef()) {
-      if (Reg && (PhysRegDefs.test(Reg) || PhysRegClobbers.test(Reg)))
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arsenm wrote:

Could pre-commit removal of the redundant !Reg check 

https://github.com/llvm/llvm-project/pull/94608