[llvm] [MachineCopyPropagation][NFC] Refactor EliminateSpillageCopies (PR #192609)

[David Green via llvm-commits]

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@@ -1415,6 +1428,11 @@ void MachineCopyPropagation::eliminateSpillageCopies(MachineBasicBlock &MBB) {
     SmallSet<Register, 8> RegsToClobber;
     if (!CopyOperands) {
       for (const MachineOperand &MO : MI.operands()) {
+        if (MO.isRegMask()) {
+          BitVector &PreservedRegUnits = Tracker.getPreservedRegUnits(MO, *TRI);
+          Tracker.clobberNonPreservedRegs(PreservedRegUnits, *TRI, *TII,
+                                          UseCopyInstr);
+        }
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davemgreen wrote:

This could continue here too, to be explicit about it.

https://github.com/llvm/llvm-project/pull/192609