diff --git a/include/llvm/CodeGen/RegisterScavenging.h b/include/llvm/CodeGen/RegisterScavenging.h
index 65fdaea1047..4a82fc5ef63 100644
--- a/include/llvm/CodeGen/RegisterScavenging.h
+++ b/include/llvm/CodeGen/RegisterScavenging.h
@@ -46,14 +46,13 @@ public:
 
   /// Init - Initialize the states.
   ///
-  void init();
+  void init(MachineBasicBlock *mbb = NULL);
 
   /// Reset - Discard previous states and re-initialize the states given for
   /// the specific basic block.
   void reset(MachineBasicBlock *mbb) {
-    MBB = mbb;
     clear();
-    init();
+    init(mbb);
   }
 
   /// forward / backward - Move the internal MBB iterator and update register
diff --git a/lib/CodeGen/RegisterScavenging.cpp b/lib/CodeGen/RegisterScavenging.cpp
index 0f980a71236..6856511bcee 100644
--- a/lib/CodeGen/RegisterScavenging.cpp
+++ b/lib/CodeGen/RegisterScavenging.cpp
@@ -25,7 +25,10 @@
 #include "llvm/ADT/STLExtras.h"
 using namespace llvm;
 
-void RegScavenger::init() {
+void RegScavenger::init(MachineBasicBlock *mbb) {
+  if (mbb)
+    MBB = mbb;
+
   const MachineFunction &MF = *MBB->getParent();
   const TargetMachine &TM = MF.getTarget();
   const MRegisterInfo *RegInfo = TM.getRegisterInfo();