diff --git a/lib/CodeGen/LiveIntervalAnalysis.cpp b/lib/CodeGen/LiveIntervalAnalysis.cpp
index e936158..c542033 100644
--- a/lib/CodeGen/LiveIntervalAnalysis.cpp
+++ b/lib/CodeGen/LiveIntervalAnalysis.cpp
@@ -887,7 +887,7 @@
 
   // If the source instruction was killing the source register before the
   // merge, unset the isKill marker given the live range has been extended.
-  int UIdx = ValLREndInst->findRegisterUseOperand(IntB.reg, true);
+  int UIdx = ValLREndInst->findRegisterUseOperandIdx(IntB.reg, true);
   if (UIdx != -1)
     ValLREndInst->getOperand(UIdx).unsetIsKill();
   
diff --git a/lib/CodeGen/LiveVariables.cpp b/lib/CodeGen/LiveVariables.cpp
index 9c7f13d..4816cc1 100644
--- a/lib/CodeGen/LiveVariables.cpp
+++ b/lib/CodeGen/LiveVariables.cpp
@@ -435,7 +435,8 @@
                "Cannot have a live-in virtual register!");
         HandlePhysRegUse(*I, Ret);
         // Add live-out registers as implicit uses.
-        Ret->addRegOperand(*I, false, true);
+        if (Ret->findRegisterUseOperandIdx(*I) == -1)
+          Ret->addRegOperand(*I, false, true);
       }
     }
 
diff --git a/lib/CodeGen/MachineInstr.cpp b/lib/CodeGen/MachineInstr.cpp
index a1e7691..1c0d9cc 100644
--- a/lib/CodeGen/MachineInstr.cpp
+++ b/lib/CodeGen/MachineInstr.cpp
@@ -169,10 +169,10 @@
   }
 }
 
-/// findRegisterUseOperand() - Returns the MachineOperand that is a use of
+/// findRegisterUseOperandIdx() - Returns the MachineOperand that is a use of
 /// the specific register or -1 if it is not found. It further tightening
 /// the search criteria to a use that kills the register if isKill is true.
-int MachineInstr::findRegisterUseOperand(unsigned Reg, bool isKill){
+int MachineInstr::findRegisterUseOperandIdx(unsigned Reg, bool isKill) {
   for (unsigned i = 0, e = getNumOperands(); i != e; ++i) {
     MachineOperand &MO = getOperand(i);
     if (MO.isReg() && MO.isUse() && MO.getReg() == Reg)
diff --git a/lib/CodeGen/RegisterScavenging.cpp b/lib/CodeGen/RegisterScavenging.cpp
index 13a3619..93c63bf 100644
--- a/lib/CodeGen/RegisterScavenging.cpp
+++ b/lib/CodeGen/RegisterScavenging.cpp
@@ -235,7 +235,7 @@
   I = next(I);
   while (I != MBB->end()) {
     Dist++;
-    if (I->findRegisterUseOperand(Reg) != -1)
+    if (I->findRegisterUseOperandIdx(Reg) != -1)
         return Dist;
     I = next(I);    
   }
diff --git a/lib/CodeGen/VirtRegMap.cpp b/lib/CodeGen/VirtRegMap.cpp
index 482e336..9ae38ac 100644
--- a/lib/CodeGen/VirtRegMap.cpp
+++ b/lib/CodeGen/VirtRegMap.cpp
@@ -764,7 +764,7 @@
           // necessary.
           bool WasKill = false;
           if (SSMI) {
-            int UIdx = SSMI->findRegisterUseOperand(PhysReg, true);
+            int UIdx = SSMI->findRegisterUseOperandIdx(PhysReg, true);
             if (UIdx != -1) {
               MachineOperand &MOK = SSMI->getOperand(UIdx);
               WasKill = MOK.isKill();
@@ -849,7 +849,7 @@
         // necessary.
         bool WasKill = false;
         if (SSMI) {
-          int UIdx = SSMI->findRegisterUseOperand(PhysReg, true);
+          int UIdx = SSMI->findRegisterUseOperandIdx(PhysReg, true);
           if (UIdx != -1) {
             MachineOperand &MOK = SSMI->getOperand(UIdx);
             WasKill = MOK.isKill();
@@ -859,7 +859,7 @@
         MachineInstr *CopyMI = prior(MII);
         if (WasKill) {
           // Transfer kill to the next use.
-          int UIdx = CopyMI->findRegisterUseOperand(PhysReg);
+          int UIdx = CopyMI->findRegisterUseOperandIdx(PhysReg);
           assert(UIdx != -1);
           MachineOperand &MOU = CopyMI->getOperand(UIdx);
           MOU.setIsKill();
@@ -957,7 +957,7 @@
               // extended. Remove its kill.
               bool WasKill = false;
               if (SSMI) {
-                int UIdx = SSMI->findRegisterUseOperand(InReg, true);
+                int UIdx = SSMI->findRegisterUseOperandIdx(InReg, true);
                 if (UIdx != -1) {
                   MachineOperand &MOK = SSMI->getOperand(UIdx);
                   WasKill = MOK.isKill();
@@ -967,7 +967,7 @@
               if (NextMII != MBB.end()) {
                 // If NextMII uses InReg and the use is not a two address
                 // operand, mark it killed.
-                int UIdx = NextMII->findRegisterUseOperand(InReg);
+                int UIdx = NextMII->findRegisterUseOperandIdx(InReg);
                 if (UIdx != -1) {
                   MachineOperand &MOU = NextMII->getOperand(UIdx);
                   if (WasKill) {