diff --git a/include/llvm/Target/TargetRegInfo.h b/include/llvm/Target/TargetRegInfo.h
index d8c6a96b2cc..aab0980e18e 100644
--- a/include/llvm/Target/TargetRegInfo.h
+++ b/include/llvm/Target/TargetRegInfo.h
@@ -62,6 +62,95 @@ public:
 
 
 
+//---------------------------------------------------------------------------
+// class MachineRegInfo
+// 
+// Purpose:
+//   Interface to register info of target machine
+// 
+//--------------------------------------------------------------------------
+
+
+
+typedef hash_map<const MachineInstr *, AddedInstrns *> AddedInstrMapType;
+
+// A vector of all machine register classes
+typedef vector<const MachineRegClassInfo *> MachineRegClassArrayType;
+
+
+class MachineRegInfo : public NonCopyableV {
+
+protected:
+
+  MachineRegClassArrayType MachineRegClassArr;    
+
+  
+public:
+
+
+  // According the definition of a MachineOperand class, a Value in a
+  // machine instruction can go into either a normal register or a 
+  // condition code register. If isCCReg is true below, the ID of the condition
+  // code regiter class will be returned. Otherwise, the normal register
+  // class (eg. int, float) must be returned.
+  virtual unsigned getRegClassIDOfValue (const Value *const Val,
+					 bool isCCReg = false) const =0;
+
+
+  inline unsigned int getNumOfRegClasses() const { 
+    return MachineRegClassArr.size(); 
+  }  
+
+  const MachineRegClassInfo *const getMachineRegClass(unsigned i) const { 
+    return MachineRegClassArr[i]; 
+  }
+
+  // returns the register that is hardwired to zero if any (-1 if none)
+  virtual inline int      getZeroRegNum()     const = 0;
+
+  //virtual unsigned getRegClassIDOfValue (const Value *const Val) const = 0;
+  // this method must give the exact register class of a machine operand
+  // e.g, Int, Float, Int CC, Float CC 
+  //virtual unsigned getRCIDOfMachineOp (const MachineOperand &MO) const = 0;
+
+
+  virtual void colorArgs(const Method *const Meth, 
+			 LiveRangeInfo & LRI) const = 0;
+
+  virtual void colorCallArgs(vector<const Instruction *> & CallInstrList, 
+			     LiveRangeInfo& LRI, 
+			     AddedInstrMapType& AddedInstrMap ) const = 0 ;
+
+  virtual void colorRetArg(vector<const Instruction *> & 
+			   RetInstrList, LiveRangeInfo& LRI,
+			   AddedInstrMapType &AddedInstrMap) const =0;
+
+  // returns the reg used for pushing the address when a method is called.
+  // This can be used for other purposes between calls
+  virtual unsigned getCallAddressReg() const = 0;
+
+  // and when we return from a method. It should be made sure that this 
+  // register contains the return value when a return instruction is reached.
+  virtual unsigned getReturnAddressReg() const = 0; 
+  
+  virtual int getUnifiedRegNum(int RegClassID, int reg) const = 0;
+
+  virtual const string getUnifiedRegName(int UnifiedRegNum) const = 0;
+
+  //virtual void printReg(const LiveRange *const LR) const =0;
+
+  MachineRegInfo() { }
+
+};
+
+
+
+
+#endif
+
+
+
+#if 0
 
 //---------------------------------------------------------------------------
 // class MachineRegInfo
@@ -133,103 +222,10 @@ public:
 };
 
 
-
-
-
-
-
-#if 0
-
-class Value;
-class Instruction;
-class Method;
-class LiveRangeInfo;
-class LiveRange;
-class AddedInstrns;
-class MachineInstr;
-
-//-----------------------------------------------------------------------------
-// class MachineRegClassInfo
-// 
-// Purpose:
-//   Interface to description of machine register class (e.g., int reg class
-//   float reg class etc)
-// 
-//--------------------------------------------------------------------------
-
-class IGNode;
-class MachineRegClassInfo {
-protected:  
-  const unsigned RegClassID;        // integer ID of a reg class
-  const unsigned NumOfAvailRegs;    // # of avail for coloring -without SP etc.
-  const unsigned NumOfAllRegs;      // # of all registers -including SP,g0 etc.
-
-public:
-  
-  inline unsigned getRegClassID() const { return RegClassID; }
-  inline unsigned getNumOfAvailRegs() const { return NumOfAvailRegs; }
-  inline unsigned getNumOfAllRegs() const { return NumOfAllRegs; }
-
-
-
-  // This method should find a color which is not used by neighbors
-  // (i.e., a false position in IsColorUsedArr) and 
-  virtual void colorIGNode(IGNode * Node, bool IsColorUsedArr[] ) const = 0;
-
-
-  MachineRegClassInfo(const unsigned ID, const unsigned NVR, 
-		      const unsigned NAR): RegClassID(ID), NumOfAvailRegs(NVR),
-                                           NumOfAllRegs(NAR) { }
-};
-
-//---------------------------------------------------------------------------
-// class MachineRegInfo
-// 
-// Purpose:
-//   Interface to register info of target machine
-// 
-//--------------------------------------------------------------------------
-
-typedef hash_map<const MachineInstr *, AddedInstrns *> AddedInstrMapType;
-
-// A vector of all machine register classestypedef vector<const MachineRegClassInfo *> MachineRegClassArrayType;
-
-
-class MachineRegInfo : public NonCopyableV {
-protected:
-  MachineRegClassArrayType MachineRegClassArr;    
- 
-public:
-  inline unsigned int getNumOfRegClasses() const { 
-    return MachineRegClassArr.size(); 
-  }  
-
-  const MachineRegClassInfo *const getMachineRegClass(unsigned i) const { 
-    return MachineRegClassArr[i]; 
-  }
-
-
-  virtual unsigned getRegClassIDOfValue (const Value *const Val) const = 0;
-
-  virtual void colorArgs(const Method *const Meth, 
-			 LiveRangeInfo & LRI) const = 0;
-
-  virtual void colorCallArgs(vector<const Instruction *> & CallInstrList, 
-			     LiveRangeInfo& LRI, 
-			     AddedInstrMapType& AddedInstrMap ) const = 0;
-
-  virtual int getUnifiedRegNum(int RegClassID, int reg) const = 0;
-
-  virtual const string getUnifiedRegName(int reg) const = 0;
-
-  //virtual void printReg(const LiveRange *const LR) const =0;
-
-  MachineRegInfo() { }
-
-};
-
 #endif
 
 
 
-#endif
+
+
+
diff --git a/lib/CodeGen/RegAlloc/PhyRegAlloc.h b/lib/CodeGen/RegAlloc/PhyRegAlloc.h
index 5b5fc43435c..fcf28320cc7 100644
--- a/lib/CodeGen/RegAlloc/PhyRegAlloc.h
+++ b/lib/CodeGen/RegAlloc/PhyRegAlloc.h
@@ -66,6 +66,7 @@ class PhyRegAlloc
   const unsigned NumOfRegClasses;       // recorded here for efficiency
 
   vector<const Instruction *> CallInstrList;  // a list of all call instrs
+  vector<const Instruction *> RetInstrList;   // a list of all return instrs
 
   AddedInstrMapType AddedInstrMap;      // to store instrns added in this phase
 
diff --git a/lib/Target/SparcV9/RegAlloc/PhyRegAlloc.h b/lib/Target/SparcV9/RegAlloc/PhyRegAlloc.h
index 5b5fc43435c..fcf28320cc7 100644
--- a/lib/Target/SparcV9/RegAlloc/PhyRegAlloc.h
+++ b/lib/Target/SparcV9/RegAlloc/PhyRegAlloc.h
@@ -66,6 +66,7 @@ class PhyRegAlloc
   const unsigned NumOfRegClasses;       // recorded here for efficiency
 
   vector<const Instruction *> CallInstrList;  // a list of all call instrs
+  vector<const Instruction *> RetInstrList;   // a list of all return instrs
 
   AddedInstrMapType AddedInstrMap;      // to store instrns added in this phase