From 60dc7345eb1543546064a35c7c2c4ea08b40f9c0 Mon Sep 17 00:00:00 2001
From: Lang Hames <lhames@gmail.com>
Date: Wed, 13 May 2009 04:18:47 +0000
Subject: [PATCH] Fix for PR4121. If TwoAddressInstructionPass removes a dead
 def, and the regB operand was killed, the kill needs to be removed from
 regB's VarInfo.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@71635 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/CodeGen/TwoAddressInstructionPass.cpp | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/CodeGen/TwoAddressInstructionPass.cpp b/lib/CodeGen/TwoAddressInstructionPass.cpp
index e37639e068a..2ec0c712222 100644
--- a/lib/CodeGen/TwoAddressInstructionPass.cpp
+++ b/lib/CodeGen/TwoAddressInstructionPass.cpp
@@ -858,6 +858,12 @@ bool TwoAddressInstructionPass::runOnMachineFunction(MachineFunction &MF) {
                     }
                   }
                 }
+
+                // We're really going to nuke the old inst. If regB was marked
+                // as a kill we need to update its Kills list.
+                if (mi->getOperand(si).isKill())
+                  LV->removeVirtualRegisterKilled(regB, mi);
+
                 mbbi->erase(mi); // Nuke the old inst.
                 mi = nmi;
                 ++NumDeletes;