[llvm] [RISCV][Peephole] Clear kill flags for registers after fold VMV (PR #138847)

[Luke Lau via llvm-commits]

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@@ -585,6 +585,7 @@ bool RISCVVectorPeephole::foldUndefPassthruVMV_V_V(MachineInstr &MI) {
 
   MRI->replaceRegWith(MI.getOperand(0).getReg(), MI.getOperand(2).getReg());
   MI.eraseFromParent();
+  MRI->clearKillFlags(MI.getOperand(2).getReg());
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lukel97 wrote:

Same here, I think this should be
```suggestion
  MRI->replaceRegWith(MI.getOperand(0).getReg(), MI.getOperand(2).getReg());
  MRI->clearKillFlags(MI.getOperand(2).getReg());
  MI.eraseFromParent();
```

https://github.com/llvm/llvm-project/pull/138847