Index: lib/Target/Mips/Mips64InstrInfo.td
===================================================================
--- lib/Target/Mips/Mips64InstrInfo.td
+++ lib/Target/Mips/Mips64InstrInfo.td
@@ -440,6 +440,16 @@ def : MipsPat<(i64 (sext_inreg GPR64:$src, i32)),
 // bswap MipsPattern
 def : MipsPat<(bswap GPR64:$rt), (DSHD (DSBH GPR64:$rt))>;
 
+// Carry pattern
+def : MipsPat<(subc GPR64:$lhs, GPR64:$rhs),
+              (DSUBu GPR64:$lhs, GPR64:$rhs)>;
+let AdditionalPredicates = [NotDSP] in {
+  def : MipsPat<(addc GPR64:$lhs, GPR64:$rhs),
+                (DADDu GPR64:$lhs, GPR64:$rhs)>;
+  def : MipsPat<(addc GPR64:$lhs, immSExt16:$imm),
+                (DADDiu GPR64:$lhs, imm:$imm)>;
+}
+
 //===----------------------------------------------------------------------===//
 // Instruction aliases
 //===----------------------------------------------------------------------===//
Index: lib/Target/Mips/MipsISelLowering.cpp
===================================================================
--- lib/Target/Mips/MipsISelLowering.cpp
+++ lib/Target/Mips/MipsISelLowering.cpp
@@ -261,6 +261,9 @@ MipsTargetLowering::MipsTargetLowering(const MipsT
     setOperationAction(ISD::LOAD,               MVT::i64,   Custom);
     setOperationAction(ISD::STORE,              MVT::i64,   Custom);
     setOperationAction(ISD::FP_TO_SINT,         MVT::i64,   Custom);
+    setOperationAction(ISD::SHL_PARTS,          MVT::i64,   Custom);
+    setOperationAction(ISD::SRA_PARTS,          MVT::i64,   Custom);
+    setOperationAction(ISD::SRL_PARTS,          MVT::i64,   Custom);
   }
 
   if (!Subtarget.isGP64bit()) {
@@ -2017,10 +2020,11 @@ SDValue MipsTargetLowering::lowerATOMIC_FENCE(SDVa
 SDValue MipsTargetLowering::lowerShiftLeftParts(SDValue Op,
                                                 SelectionDAG &DAG) const {
   SDLoc DL(Op);
+  MVT VT = Subtarget.isGP64bit() ? MVT::i64 : MVT::i32;
+
   SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
   SDValue Shamt = Op.getOperand(2);
-
-  // if shamt < 32:
+  // if shamt < (VT.bits):
   //  lo = (shl lo, shamt)
   //  hi = (or (shl hi, shamt) (srl (srl lo, 1), ~shamt))
   // else:
@@ -2028,18 +2032,17 @@ SDValue MipsTargetLowering::lowerShiftLeftParts(SD
   //  hi = (shl lo, shamt[4:0])
   SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
                             DAG.getConstant(-1, MVT::i32));
-  SDValue ShiftRight1Lo = DAG.getNode(ISD::SRL, DL, MVT::i32, Lo,
-                                      DAG.getConstant(1, MVT::i32));
-  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, MVT::i32, ShiftRight1Lo,
-                                     Not);
-  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, MVT::i32, Hi, Shamt);
-  SDValue Or = DAG.getNode(ISD::OR, DL, MVT::i32, ShiftLeftHi, ShiftRightLo);
-  SDValue ShiftLeftLo = DAG.getNode(ISD::SHL, DL, MVT::i32, Lo, Shamt);
+  SDValue ShiftRight1Lo = DAG.getNode(ISD::SRL, DL, VT, Lo,
+                                      DAG.getConstant(1, VT));
+  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, VT, ShiftRight1Lo, Not);
+  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, VT, Hi, Shamt);
+  SDValue Or = DAG.getNode(ISD::OR, DL, VT, ShiftLeftHi, ShiftRightLo);
+  SDValue ShiftLeftLo = DAG.getNode(ISD::SHL, DL, VT, Lo, Shamt);
   SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
                              DAG.getConstant(0x20, MVT::i32));
-  Lo = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond,
-                   DAG.getConstant(0, MVT::i32), ShiftLeftLo);
-  Hi = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond, ShiftLeftLo, Or);
+  Lo = DAG.getNode(ISD::SELECT, DL, VT, Cond,
+                   DAG.getConstant(0, VT), ShiftLeftLo);
+  Hi = DAG.getNode(ISD::SELECT, DL, VT, Cond, ShiftLeftLo, Or);
 
   SDValue Ops[2] = {Lo, Hi};
   return DAG.getMergeValues(Ops, DL);
@@ -2050,8 +2053,9 @@ SDValue MipsTargetLowering::lowerShiftRightParts(S
   SDLoc DL(Op);
   SDValue Lo = Op.getOperand(0), Hi = Op.getOperand(1);
   SDValue Shamt = Op.getOperand(2);
+  MVT VT = Subtarget.isGP64bit() ? MVT::i64 : MVT::i32;
 
-  // if shamt < 32:
+  // if shamt < (VT.bits):
   //  lo = (or (shl (shl hi, 1), ~shamt) (srl lo, shamt))
   //  if isSRA:
   //    hi = (sra hi, shamt)
@@ -2066,21 +2070,19 @@ SDValue MipsTargetLowering::lowerShiftRightParts(S
   //   hi = 0
   SDValue Not = DAG.getNode(ISD::XOR, DL, MVT::i32, Shamt,
                             DAG.getConstant(-1, MVT::i32));
-  SDValue ShiftLeft1Hi = DAG.getNode(ISD::SHL, DL, MVT::i32, Hi,
-                                     DAG.getConstant(1, MVT::i32));
-  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, MVT::i32, ShiftLeft1Hi, Not);
-  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, MVT::i32, Lo, Shamt);
-  SDValue Or = DAG.getNode(ISD::OR, DL, MVT::i32, ShiftLeftHi, ShiftRightLo);
-  SDValue ShiftRightHi = DAG.getNode(IsSRA ? ISD::SRA : ISD::SRL, DL, MVT::i32,
-                                     Hi, Shamt);
+  SDValue ShiftLeft1Hi = DAG.getNode(ISD::SHL, DL, VT, Hi,
+                                     DAG.getConstant(1, VT));
+  SDValue ShiftLeftHi = DAG.getNode(ISD::SHL, DL, VT, ShiftLeft1Hi, Not);
+  SDValue ShiftRightLo = DAG.getNode(ISD::SRL, DL, VT, Lo, Shamt);
+  SDValue Or = DAG.getNode(ISD::OR, DL, VT, ShiftLeftHi, ShiftRightLo);
+  SDValue ShiftRightHi = DAG.getNode(IsSRA ? ISD::SRA : ISD::SRL,
+                                     DL, VT, Hi, Shamt);
   SDValue Cond = DAG.getNode(ISD::AND, DL, MVT::i32, Shamt,
                              DAG.getConstant(0x20, MVT::i32));
-  SDValue Shift31 = DAG.getNode(ISD::SRA, DL, MVT::i32, Hi,
-                                DAG.getConstant(31, MVT::i32));
-  Lo = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond, ShiftRightHi, Or);
-  Hi = DAG.getNode(ISD::SELECT, DL, MVT::i32, Cond,
-                   IsSRA ? Shift31 : DAG.getConstant(0, MVT::i32),
-                   ShiftRightHi);
+  SDValue Shift31 = DAG.getNode(ISD::SRA, DL, VT, Hi, DAG.getConstant(31, VT));
+  Lo = DAG.getNode(ISD::SELECT, DL, VT, Cond, ShiftRightHi, Or);
+  Hi = DAG.getNode(ISD::SELECT, DL, VT, Cond,
+                   IsSRA ? Shift31 : DAG.getConstant(0, VT), ShiftRightHi);
 
   SDValue Ops[2] = {Lo, Hi};
   return DAG.getMergeValues(Ops, DL);
Index: lib/Target/Mips/MipsSEISelDAGToDAG.cpp
===================================================================
--- lib/Target/Mips/MipsSEISelDAGToDAG.cpp
+++ lib/Target/Mips/MipsSEISelDAGToDAG.cpp
@@ -236,13 +236,31 @@ SDNode *MipsSEDAGToDAGISel::selectAddESubE(unsigne
           (Opc == ISD::SUBC || Opc == ISD::SUBE)) &&
          "(ADD|SUB)E flag operand must come from (ADD|SUB)C/E insn");
 
+  unsigned SLTuOp = Mips::SLTu, ADDuOp = Mips::ADDu;
+  if (Subtarget->isGP64bit()) {
+    SLTuOp = Mips::SLTu64;
+    ADDuOp = Mips::DADDu;
+  }
+
   SDValue Ops[] = { CmpLHS, InFlag.getOperand(1) };
   SDValue LHS = Node->getOperand(0), RHS = Node->getOperand(1);
   EVT VT = LHS.getValueType();
 
-  SDNode *Carry = CurDAG->getMachineNode(Mips::SLTu, DL, VT, Ops);
-  SDNode *AddCarry = CurDAG->getMachineNode(Mips::ADDu, DL, VT,
+  SDNode *Carry = CurDAG->getMachineNode(SLTuOp, DL, VT, Ops);
+
+  if (Subtarget->isGP64bit()) {
+    // On 64-bit targets, sltu produces an i64 but our backend currently says
+    // that SLTu64 produces an i32. We need to fix this in the long run but for
+    // now, just make the DAG type-correct by asserting the upper bits are zero.
+    Carry = CurDAG->getMachineNode(Mips::SUBREG_TO_REG, DL, VT,
+                                   CurDAG->getTargetConstant(0, VT),
+                                   SDValue(Carry, 0),
+                                   CurDAG->getTargetConstant(Mips::sub_32, VT));
+  }
+
+  SDNode *AddCarry = CurDAG->getMachineNode(ADDuOp, DL, VT,
                                             SDValue(Carry, 0), RHS);
+
   return CurDAG->SelectNodeTo(Node, MOp, VT, MVT::Glue, LHS,
                               SDValue(AddCarry, 0));
 }
@@ -641,7 +659,8 @@ std::pair<bool, SDNode*> MipsSEDAGToDAGISel::selec
 
   case ISD::SUBE: {
     SDValue InFlag = Node->getOperand(2);
-    Result = selectAddESubE(Mips::SUBu, InFlag, InFlag.getOperand(0), DL, Node);
+    unsigned Opc = Subtarget->isGP64bit() ? Mips::DSUBu : Mips::SUBu;
+    Result = selectAddESubE(Opc, InFlag, InFlag.getOperand(0), DL, Node);
     return std::make_pair(true, Result);
   }
 
@@ -649,7 +668,8 @@ std::pair<bool, SDNode*> MipsSEDAGToDAGISel::selec
     if (Subtarget->hasDSP()) // Select DSP instructions, ADDSC and ADDWC.
       break;
     SDValue InFlag = Node->getOperand(2);
-    Result = selectAddESubE(Mips::ADDu, InFlag, InFlag.getValue(0), DL, Node);
+    unsigned Opc = Subtarget->isGP64bit() ? Mips::DADDu : Mips::ADDu;
+    Result = selectAddESubE(Opc, InFlag, InFlag.getValue(0), DL, Node);
     return std::make_pair(true, Result);
   }
 
Index: lib/Target/Mips/MipsSEISelLowering.cpp
===================================================================
--- lib/Target/Mips/MipsSEISelLowering.cpp
+++ lib/Target/Mips/MipsSEISelLowering.cpp
@@ -122,6 +122,8 @@ MipsSETargetLowering::MipsSETargetLowering(const M
     setOperationAction(ISD::MUL,              MVT::i64, Custom);
 
   if (Subtarget.isGP64bit()) {
+    setOperationAction(ISD::SMUL_LOHI,        MVT::i64, Custom);
+    setOperationAction(ISD::UMUL_LOHI,        MVT::i64, Custom);
     setOperationAction(ISD::MULHS,            MVT::i64, Custom);
     setOperationAction(ISD::MULHU,            MVT::i64, Custom);
     setOperationAction(ISD::SDIVREM,          MVT::i64, Custom);
@@ -200,6 +202,8 @@ MipsSETargetLowering::MipsSETargetLowering(const M
   if (Subtarget.hasMips64r6()) {
     // MIPS64r6 replaces the accumulator-based multiplies with a three register
     // instruction
+    setOperationAction(ISD::SMUL_LOHI, MVT::i64, Expand);
+    setOperationAction(ISD::UMUL_LOHI, MVT::i64, Expand);
     setOperationAction(ISD::MUL, MVT::i64, Legal);
     setOperationAction(ISD::MULHS, MVT::i64, Legal);
     setOperationAction(ISD::MULHU, MVT::i64, Legal);