Index: lib/Target/Mips/MipsISelLowering.h
===================================================================
--- lib/Target/Mips/MipsISelLowering.h
+++ lib/Target/Mips/MipsISelLowering.h
@@ -343,9 +343,8 @@
     struct ByValArgInfo {
       unsigned FirstIdx; // Index of the first register used.
       unsigned NumRegs;  // Number of registers used for this argument.
-      unsigned Address;  // Offset of the stack area used to pass this argument.
 
-      ByValArgInfo() : FirstIdx(0), NumRegs(0), Address(0) {}
+      ByValArgInfo() : FirstIdx(0), NumRegs(0) {}
     };
 
     /// MipsCC - This class provides methods used to analyze formal and call
@@ -479,20 +478,20 @@
     /// copyByValArg - Copy argument registers which were used to pass a byval
     /// argument to the stack. Create a stack frame object for the byval
     /// argument.
-    void copyByValRegs(SDValue Chain, SDLoc DL,
-                       std::vector<SDValue> &OutChains, SelectionDAG &DAG,
-                       const ISD::ArgFlagsTy &Flags,
+    void copyByValRegs(SDValue Chain, SDLoc DL, std::vector<SDValue> &OutChains,
+                       SelectionDAG &DAG, const ISD::ArgFlagsTy &Flags,
                        SmallVectorImpl<SDValue> &InVals,
-                       const Argument *FuncArg,
-                       const MipsCC &CC, const ByValArgInfo &ByVal) const;
+                       const Argument *FuncArg, const MipsCC &CC,
+                       const ByValArgInfo &ByVal, const CCValAssign &VA) const;
 
     /// passByValArg - Pass a byval argument in registers or on stack.
     void passByValArg(SDValue Chain, SDLoc DL,
-                      std::deque< std::pair<unsigned, SDValue> > &RegsToPass,
+                      std::deque<std::pair<unsigned, SDValue>> &RegsToPass,
                       SmallVectorImpl<SDValue> &MemOpChains, SDValue StackPtr,
                       MachineFrameInfo *MFI, SelectionDAG &DAG, SDValue Arg,
                       const MipsCC &CC, const ByValArgInfo &ByVal,
-                      const ISD::ArgFlagsTy &Flags, bool isLittle) const;
+                      const ISD::ArgFlagsTy &Flags, bool isLittle,
+                      const CCValAssign &VA) const;
 
     /// writeVarArgRegs - Write variable function arguments passed in registers
     /// to the stack. Also create a stack frame object for the first variable
Index: lib/Target/Mips/MipsISelLowering.cpp
===================================================================
--- lib/Target/Mips/MipsISelLowering.cpp
+++ lib/Target/Mips/MipsISelLowering.cpp
@@ -2647,7 +2647,7 @@
       assert(!IsTailCall &&
              "Do not tail-call optimize if there is a byval argument.");
       passByValArg(Chain, DL, RegsToPass, MemOpChains, StackPtr, MFI, DAG, Arg,
-                   MipsCCInfo, *ByValArg, Flags, Subtarget.isLittle());
+                   MipsCCInfo, *ByValArg, Flags, Subtarget.isLittle(), VA);
       ++ByValArg;
       continue;
     }
@@ -2905,7 +2905,7 @@
              "ByVal args of size 0 should have been ignored by front-end.");
       assert(ByValArg != MipsCCInfo.byval_end());
       copyByValRegs(Chain, DL, OutChains, DAG, Flags, InVals, &*FuncArg,
-                    MipsCCInfo, *ByValArg);
+                    MipsCCInfo, *ByValArg, VA);
       ++ByValArg;
       continue;
     }
@@ -3675,10 +3675,9 @@
     allocateRegs(ByVal, ByValSize, Align, State);
 
   // Allocate space on caller's stack.
-  ByVal.Address =
+  unsigned Offset =
       State.AllocateStack(ByValSize - RegSizeInBytes * ByVal.NumRegs, Align);
-  State.addLoc(
-      CCValAssign::getMem(ValNo, ValVT, ByVal.Address, LocVT, LocInfo));
+  State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
   ByValArgs.push_back(ByVal);
 }
 
@@ -3736,11 +3735,11 @@
   return VT;
 }
 
-void MipsTargetLowering::
-copyByValRegs(SDValue Chain, SDLoc DL, std::vector<SDValue> &OutChains,
-              SelectionDAG &DAG, const ISD::ArgFlagsTy &Flags,
-              SmallVectorImpl<SDValue> &InVals, const Argument *FuncArg,
-              const MipsCC &CC, const ByValArgInfo &ByVal) const {
+void MipsTargetLowering::copyByValRegs(
+    SDValue Chain, SDLoc DL, std::vector<SDValue> &OutChains, SelectionDAG &DAG,
+    const ISD::ArgFlagsTy &Flags, SmallVectorImpl<SDValue> &InVals,
+    const Argument *FuncArg, const MipsCC &CC, const ByValArgInfo &ByVal,
+    const CCValAssign &VA) const {
   MachineFunction &MF = DAG.getMachineFunction();
   MachineFrameInfo *MFI = MF.getFrameInfo();
   unsigned GPRSizeInBytes = Subtarget.getGPRSizeInBytes();
@@ -3753,7 +3752,7 @@
         (int)CC.reservedArgArea() -
         (int)((CC.intArgRegs().size() - ByVal.FirstIdx) * GPRSizeInBytes);
   else
-    FrameObjOffset = ByVal.Address;
+    FrameObjOffset = VA.getLocMemOffset();
 
   // Create frame object.
   EVT PtrTy = getPointerTy();
@@ -3782,13 +3781,13 @@
 }
 
 // Copy byVal arg to registers and stack.
-void MipsTargetLowering::
-passByValArg(SDValue Chain, SDLoc DL,
-             std::deque< std::pair<unsigned, SDValue> > &RegsToPass,
-             SmallVectorImpl<SDValue> &MemOpChains, SDValue StackPtr,
-             MachineFrameInfo *MFI, SelectionDAG &DAG, SDValue Arg,
-             const MipsCC &CC, const ByValArgInfo &ByVal,
-             const ISD::ArgFlagsTy &Flags, bool isLittle) const {
+void MipsTargetLowering::passByValArg(
+    SDValue Chain, SDLoc DL,
+    std::deque<std::pair<unsigned, SDValue>> &RegsToPass,
+    SmallVectorImpl<SDValue> &MemOpChains, SDValue StackPtr,
+    MachineFrameInfo *MFI, SelectionDAG &DAG, SDValue Arg, const MipsCC &CC,
+    const ByValArgInfo &ByVal, const ISD::ArgFlagsTy &Flags, bool isLittle,
+    const CCValAssign &VA) const {
   unsigned ByValSizeInBytes = Flags.getByValSize();
   unsigned OffsetInBytes = 0; // From beginning of struct
   unsigned RegSizeInBytes = Subtarget.getGPRSizeInBytes();
@@ -3872,7 +3871,7 @@
   SDValue Src = DAG.getNode(ISD::ADD, DL, PtrTy, Arg,
                             DAG.getConstant(OffsetInBytes, PtrTy));
   SDValue Dst = DAG.getNode(ISD::ADD, DL, PtrTy, StackPtr,
-                            DAG.getIntPtrConstant(ByVal.Address));
+                            DAG.getIntPtrConstant(VA.getLocMemOffset()));
   Chain = DAG.getMemcpy(Chain, DL, Dst, Src, DAG.getConstant(MemCpySize, PtrTy),
                         Alignment, /*isVolatile=*/false, /*AlwaysInline=*/false,
                         MachinePointerInfo(), MachinePointerInfo());