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.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@83249 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/PostRASchedulerList.cpp b/lib/CodeGen/PostRASchedulerList.cpp
index 902f50517c5f70fdc92ed416792d8394be931dda..662ab01a37cfb3f6464a81c9beae96b9a875fb0f 100644 (file)
--- a/lib/CodeGen/PostRASchedulerList.cpp
+++ b/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;
 }