diff --git a/include/llvm/CodeGen/MachineCodeForInstruction.h b/include/llvm/CodeGen/MachineCodeForInstruction.h
index 2193a80e529..f4ec42dbf3d 100644
--- a/include/llvm/CodeGen/MachineCodeForInstruction.h
+++ b/include/llvm/CodeGen/MachineCodeForInstruction.h
@@ -23,12 +23,14 @@
 class MachineInstr;
 class Instruction;
 class Value;
+class CallArgsDescriptor;
 
 extern AnnotationID MCFI_AID;
 
 class MachineCodeForInstruction : public Annotation {
-  std::vector<Value*> tempVec;         // used by m/c instr but not VM instr
-  std::vector<MachineInstr*> Contents;
+  std::vector<Value*> tempVec;          // used by m/c instr but not VM instr
+  std::vector<MachineInstr*> Contents;  // the machine instr for this VM instr
+  CallArgsDescriptor* callArgsDesc;     // only used for CALL instructions
 public:
   MachineCodeForInstruction() : Annotation(MCFI_AID) {}
   ~MachineCodeForInstruction();
@@ -81,6 +83,9 @@ public:
     tempVec.push_back(tmp);
     return *this;
   }
+
+  void setCallArgsDescriptor(CallArgsDescriptor* desc) { callArgsDesc = desc; }
+  CallArgsDescriptor* getCallArgsDescriptor() const    { return callArgsDesc; }
 };
 
 #endif
diff --git a/lib/CodeGen/MachineCodeForInstruction.cpp b/lib/CodeGen/MachineCodeForInstruction.cpp
index f3080628ee8..7b2fb75c653 100644
--- a/lib/CodeGen/MachineCodeForInstruction.cpp
+++ b/lib/CodeGen/MachineCodeForInstruction.cpp
@@ -17,6 +17,7 @@
 
 #include "llvm/CodeGen/MachineCodeForInstruction.h"
 #include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/CodeGen/MachineInstrAnnot.h"
 #include "llvm/CodeGen/InstrSelection.h"
 
 AnnotationID MCFI_AID(
@@ -55,4 +56,8 @@ MachineCodeForInstruction::~MachineCodeForInstruction()
   // Free the MachineInstr objects allocated, if any.
   for (unsigned i=0, N = size(); i < N; i++)
     delete (*this)[i];
+
+  // Free the CallArgsDescriptor if it exists.
+  if (callArgsDesc)
+    delete callArgsDesc;
 }
diff --git a/lib/Target/SparcV9/MachineCodeForInstruction.h b/lib/Target/SparcV9/MachineCodeForInstruction.h
index 2193a80e529..f4ec42dbf3d 100644
--- a/lib/Target/SparcV9/MachineCodeForInstruction.h
+++ b/lib/Target/SparcV9/MachineCodeForInstruction.h
@@ -23,12 +23,14 @@
 class MachineInstr;
 class Instruction;
 class Value;
+class CallArgsDescriptor;
 
 extern AnnotationID MCFI_AID;
 
 class MachineCodeForInstruction : public Annotation {
-  std::vector<Value*> tempVec;         // used by m/c instr but not VM instr
-  std::vector<MachineInstr*> Contents;
+  std::vector<Value*> tempVec;          // used by m/c instr but not VM instr
+  std::vector<MachineInstr*> Contents;  // the machine instr for this VM instr
+  CallArgsDescriptor* callArgsDesc;     // only used for CALL instructions
 public:
   MachineCodeForInstruction() : Annotation(MCFI_AID) {}
   ~MachineCodeForInstruction();
@@ -81,6 +83,9 @@ public:
     tempVec.push_back(tmp);
     return *this;
   }
+
+  void setCallArgsDescriptor(CallArgsDescriptor* desc) { callArgsDesc = desc; }
+  CallArgsDescriptor* getCallArgsDescriptor() const    { return callArgsDesc; }
 };
 
 #endif