[llvm] [CodeGen] Check physical def kill flag in MachineInstr::isDead (PR #168684)

[Luke Lau via llvm-commits]

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@@ -1398,7 +1398,8 @@ bool MachineInstr::isDead(const MachineRegisterInfo &MRI,
     Register Reg = MO.getReg();
     if (Reg.isPhysical()) {
       // Don't delete live physreg defs, or any reserved register defs.
-      if (!LivePhysRegs || !LivePhysRegs->available(Reg) || MRI.isReserved(Reg))
+      if ((!MO.isDead() && (!LivePhysRegs || !LivePhysRegs->available(Reg))) ||
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lukel97 wrote:

Thanks for catching that, fixed in 577cf9acfc5b

https://github.com/llvm/llvm-project/pull/168684