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

[Jay Foad via llvm-commits]

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@@ -448,7 +463,7 @@ void MachineLICMBase::ProcessMI(MachineInstr *MI, BitVector &PhysRegDefs,
     // We can't hoist an instruction defining a physreg that is clobbered in
     // the loop.
     if (MO.isRegMask()) {
-      PhysRegClobbers.setBitsNotInMask(MO.getRegMask());
+      applyBitsNotInRegMaskToRegUnitsMask(TRI, RUClobbers, MO.getRegMask());
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jayfoad wrote:

The regmask includes sgpr4, which means the call preserves s4, so we _can_ hoist a def of s4.

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