From 3b008a3a65d2e66362e2391d29290a8f4707d32a Mon Sep 17 00:00:00 2001
From: Benjamin Kramer <benny.kra@googlemail.com>
Date: Fri, 2 Oct 2009 15:59:52 +0000
Subject: [PATCH] Fix a use-after-free in post-ra-scheduling.

MI->addOperand invalidates references to it's operands, avoid touching
the operand after a new one was added.

llvm-svn: 83249
---
 llvm/lib/CodeGen/PostRASchedulerList.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/CodeGen/PostRASchedulerList.cpp b/llvm/lib/CodeGen/PostRASchedulerList.cpp
index 902f50517c5f..662ab01a37cf 100644
--- a/llvm/lib/CodeGen/PostRASchedulerList.cpp
+++ b/llvm/lib/CodeGen/PostRASchedulerList.cpp
@@ -884,6 +884,7 @@ bool SchedulePostRATDList::ToggleKillFlag(MachineInstr *MI,
 
   // If any subreg of MO is live, then create an imp-def for that
   // subreg and keep MO marked as killed.
+  MO.setIsKill(false);
   bool AllDead = true;
   const unsigned SuperReg = MO.getReg();
   for (const unsigned *Subreg = TRI->getSubRegisters(SuperReg);
@@ -898,7 +899,8 @@ bool SchedulePostRATDList::ToggleKillFlag(MachineInstr *MI,
     }
   }
 
-  MO.setIsKill(AllDead);
+  if(AllDead)
+    MO.setIsKill(true);
   return false;
 }
 
-- 
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