[llvm] [AArch64] Fix an incorrect handling of debug values in MachineSink (PR #68107)

[Momchil Velikov via llvm-commits]

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@@ -528,7 +528,10 @@ bool MachineSinking::PerformSinkAndFold(MachineInstr &MI,
           continue;
         MachineInstr *NewDbgMI = SinkDst->getMF()->CloneMachineInstr(DbgMI);
         SinkMBB.insertAfter(InsertPt, NewDbgMI);
-        NewDbgMI->getOperand(0).setReg(DstReg);
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momchil-velikov wrote:

To clarify, that `getOperand(0)` works for `DBG_VALUE`s only, other debug instructions can have operands using `DefReg` at other positions.

https://github.com/llvm/llvm-project/pull/68107