diff --git a/include/llvm/CodeGen/MachineInstr.h b/include/llvm/CodeGen/MachineInstr.h
index cb807292292..339371227d2 100644
--- a/include/llvm/CodeGen/MachineInstr.h
+++ b/include/llvm/CodeGen/MachineInstr.h
@@ -147,6 +147,14 @@ public:
     regNum = reg;
   }
 
+  // used to get the reg number if when one is allocted (must be
+  // called only after reg alloc)
+  inline unsigned int  getAllocatedRegNum() const {
+    assert(opType == MO_VirtualRegister || opType == MO_CCRegister || 
+	   opType == MO_MachineRegister);
+    return regNum;
+  }
+
  
 };