Updating branches/google/stable to r178511stable

git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/google/stable@178655 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 22 insertions, 648 deletions

diff --git a/lib/Target/Mips/MipsISelDAGToDAG.cpp b/lib/Target/Mips/MipsISelDAGToDAG.cpp
index 6dff548505..77b08cb11e 100644
--- a/lib/Target/Mips/MipsISelDAGToDAG.cpp
+++ b/lib/Target/Mips/MipsISelDAGToDAG.cpp
@@ -12,19 +12,19 @@
 //===----------------------------------------------------------------------===//
 
 #define DEBUG_TYPE "mips-isel"
+#include "MipsISelDAGToDAG.h"
+#include "Mips16ISelDAGToDAG.h"
+#include "MipsSEISelDAGToDAG.h"
 #include "Mips.h"
 #include "MCTargetDesc/MipsBaseInfo.h"
 #include "MipsAnalyzeImmediate.h"
 #include "MipsMachineFunction.h"
 #include "MipsRegisterInfo.h"
-#include "MipsSubtarget.h"
-#include "MipsTargetMachine.h"
 #include "llvm/CodeGen/MachineConstantPool.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
 #include "llvm/CodeGen/MachineInstrBuilder.h"
 #include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/CodeGen/SelectionDAGISel.h"
 #include "llvm/CodeGen/SelectionDAGNodes.h"
 #include "llvm/IR/GlobalValue.h"
 #include "llvm/IR/Instructions.h"
@@ -45,270 +45,11 @@ using namespace llvm;
 // MipsDAGToDAGISel - MIPS specific code to select MIPS machine
 // instructions for SelectionDAG operations.
 //===----------------------------------------------------------------------===//
-namespace {
-
-class MipsDAGToDAGISel : public SelectionDAGISel {
-
-  /// TM - Keep a reference to MipsTargetMachine.
-  MipsTargetMachine &TM;
-
-  /// Subtarget - Keep a pointer to the MipsSubtarget around so that we can
-  /// make the right decision when generating code for different targets.
-  const MipsSubtarget &Subtarget;
-
-public:
-  explicit MipsDAGToDAGISel(MipsTargetMachine &tm) :
-  SelectionDAGISel(tm),
-  TM(tm), Subtarget(tm.getSubtarget<MipsSubtarget>()) {}
-
-  // Pass Name
-  virtual const char *getPassName() const {
-    return "MIPS DAG->DAG Pattern Instruction Selection";
-  }
-
-  virtual bool runOnMachineFunction(MachineFunction &MF);
-
-private:
-  // Include the pieces autogenerated from the target description.
-  #include "MipsGenDAGISel.inc"
-
-  /// getTargetMachine - Return a reference to the TargetMachine, casted
-  /// to the target-specific type.
-  const MipsTargetMachine &getTargetMachine() {
-    return static_cast<const MipsTargetMachine &>(TM);
-  }
-
-  /// getInstrInfo - Return a reference to the TargetInstrInfo, casted
-  /// to the target-specific type.
-  const MipsInstrInfo *getInstrInfo() {
-    return getTargetMachine().getInstrInfo();
-  }
-
-  SDNode *getGlobalBaseReg();
-
-  SDValue getMips16SPAliasReg();
-
-  void getMips16SPRefReg(SDNode *parent, SDValue &AliasReg);
-
-  std::pair<SDNode*, SDNode*> SelectMULT(SDNode *N, unsigned Opc, DebugLoc dl,
-                                         EVT Ty, bool HasLo, bool HasHi);
-
-  SDNode *Select(SDNode *N);
-
-  // Complex Pattern.
-  /// (reg + imm).
-  bool selectAddrRegImm(SDValue Addr, SDValue &Base, SDValue &Offset) const;
-
-  /// Fall back on this function if all else fails.
-  bool selectAddrDefault(SDValue Addr, SDValue &Base, SDValue &Offset) const;
-
-  /// Match integer address pattern.
-  bool selectIntAddr(SDValue Addr, SDValue &Base, SDValue &Offset) const;
-
-  bool SelectAddr16(SDNode *Parent, SDValue N, SDValue &Base, SDValue &Offset,
-       SDValue &Alias);
-
-  // getImm - Return a target constant with the specified value.
-  inline SDValue getImm(const SDNode *Node, uint64_t Imm) {
-    return CurDAG->getTargetConstant(Imm, Node->getValueType(0));
-  }
-
-  void ProcessFunctionAfterISel(MachineFunction &MF);
-  bool ReplaceUsesWithZeroReg(MachineRegisterInfo *MRI, const MachineInstr&);
-  void InitGlobalBaseReg(MachineFunction &MF);
-  void InitMips16SPAliasReg(MachineFunction &MF);
-
-  virtual bool SelectInlineAsmMemoryOperand(const SDValue &Op,
-                                            char ConstraintCode,
-                                            std::vector<SDValue> &OutOps);
-};
-
-}
-
-// Insert instructions to initialize the global base register in the
-// first MBB of the function. When the ABI is O32 and the relocation model is
-// PIC, the necessary instructions are emitted later to prevent optimization
-// passes from moving them.
-void MipsDAGToDAGISel::InitGlobalBaseReg(MachineFunction &MF) {
-  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
-
-  if (!MipsFI->globalBaseRegSet())
-    return;
-
-  MachineBasicBlock &MBB = MF.front();
-  MachineBasicBlock::iterator I = MBB.begin();
-  MachineRegisterInfo &RegInfo = MF.getRegInfo();
-  const TargetInstrInfo &TII = *MF.getTarget().getInstrInfo();
-  DebugLoc DL = I != MBB.end() ? I->getDebugLoc() : DebugLoc();
-  unsigned V0, V1, V2, GlobalBaseReg = MipsFI->getGlobalBaseReg();
-  const TargetRegisterClass *RC;
-
-  if (Subtarget.isABI_N64())
-    RC = (const TargetRegisterClass*)&Mips::CPU64RegsRegClass;
-  else if (Subtarget.inMips16Mode())
-    RC = (const TargetRegisterClass*)&Mips::CPU16RegsRegClass;
-  else
-    RC = (const TargetRegisterClass*)&Mips::CPURegsRegClass;
-
-  V0 = RegInfo.createVirtualRegister(RC);
-  V1 = RegInfo.createVirtualRegister(RC);
-  V2 = RegInfo.createVirtualRegister(RC);
-
-  if (Subtarget.isABI_N64()) {
-    MF.getRegInfo().addLiveIn(Mips::T9_64);
-    MBB.addLiveIn(Mips::T9_64);
-
-    // lui $v0, %hi(%neg(%gp_rel(fname)))
-    // daddu $v1, $v0, $t9
-    // daddiu $globalbasereg, $v1, %lo(%neg(%gp_rel(fname)))
-    const GlobalValue *FName = MF.getFunction();
-    BuildMI(MBB, I, DL, TII.get(Mips::LUi64), V0)
-      .addGlobalAddress(FName, 0, MipsII::MO_GPOFF_HI);
-    BuildMI(MBB, I, DL, TII.get(Mips::DADDu), V1).addReg(V0)
-      .addReg(Mips::T9_64);
-    BuildMI(MBB, I, DL, TII.get(Mips::DADDiu), GlobalBaseReg).addReg(V1)
-      .addGlobalAddress(FName, 0, MipsII::MO_GPOFF_LO);
-    return;
-  }
-
-  if (Subtarget.inMips16Mode()) {
-    BuildMI(MBB, I, DL, TII.get(Mips::LiRxImmX16), V0)
-      .addExternalSymbol("_gp_disp", MipsII::MO_ABS_HI);
-    BuildMI(MBB, I, DL, TII.get(Mips::AddiuRxPcImmX16), V1)
-      .addExternalSymbol("_gp_disp", MipsII::MO_ABS_LO);
-    BuildMI(MBB, I, DL, TII.get(Mips::SllX16), V2).addReg(V0).addImm(16);
-    BuildMI(MBB, I, DL, TII.get(Mips::AdduRxRyRz16), GlobalBaseReg)
-      .addReg(V1).addReg(V2);
-    return;
-  }
-
-  if (MF.getTarget().getRelocationModel() == Reloc::Static) {
-    // Set global register to __gnu_local_gp.
-    //
-    // lui   $v0, %hi(__gnu_local_gp)
-    // addiu $globalbasereg, $v0, %lo(__gnu_local_gp)
-    BuildMI(MBB, I, DL, TII.get(Mips::LUi), V0)
-      .addExternalSymbol("__gnu_local_gp", MipsII::MO_ABS_HI);
-    BuildMI(MBB, I, DL, TII.get(Mips::ADDiu), GlobalBaseReg).addReg(V0)
-      .addExternalSymbol("__gnu_local_gp", MipsII::MO_ABS_LO);
-    return;
-  }
-
-  MF.getRegInfo().addLiveIn(Mips::T9);
-  MBB.addLiveIn(Mips::T9);
-
-  if (Subtarget.isABI_N32()) {
-    // lui $v0, %hi(%neg(%gp_rel(fname)))
-    // addu $v1, $v0, $t9
-    // addiu $globalbasereg, $v1, %lo(%neg(%gp_rel(fname)))
-    const GlobalValue *FName = MF.getFunction();
-    BuildMI(MBB, I, DL, TII.get(Mips::LUi), V0)
-      .addGlobalAddress(FName, 0, MipsII::MO_GPOFF_HI);
-    BuildMI(MBB, I, DL, TII.get(Mips::ADDu), V1).addReg(V0).addReg(Mips::T9);
-    BuildMI(MBB, I, DL, TII.get(Mips::ADDiu), GlobalBaseReg).addReg(V1)
-      .addGlobalAddress(FName, 0, MipsII::MO_GPOFF_LO);
-    return;
-  }
-
-  assert(Subtarget.isABI_O32());
-
-  // For O32 ABI, the following instruction sequence is emitted to initialize
-  // the global base register:
-  //
-  //  0. lui   $2, %hi(_gp_disp)
-  //  1. addiu $2, $2, %lo(_gp_disp)
-  //  2. addu  $globalbasereg, $2, $t9
-  //
-  // We emit only the last instruction here.
-  //
-  // GNU linker requires that the first two instructions appear at the beginning
-  // of a function and no instructions be inserted before or between them.
-  // The two instructions are emitted during lowering to MC layer in order to
-  // avoid any reordering.
-  //
-  // Register $2 (Mips::V0) is added to the list of live-in registers to ensure
-  // the value instruction 1 (addiu) defines is valid when instruction 2 (addu)
-  // reads it.
-  MF.getRegInfo().addLiveIn(Mips::V0);
-  MBB.addLiveIn(Mips::V0);
-  BuildMI(MBB, I, DL, TII.get(Mips::ADDu), GlobalBaseReg)
-    .addReg(Mips::V0).addReg(Mips::T9);
-}
-
-// Insert instructions to initialize the Mips16 SP Alias register in the
-// first MBB of the function.
-//
-void MipsDAGToDAGISel::InitMips16SPAliasReg(MachineFunction &MF) {
-  MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
-
-  if (!MipsFI->mips16SPAliasRegSet())
-    return;
-
-  MachineBasicBlock &MBB = MF.front();
-  MachineBasicBlock::iterator I = MBB.begin();
-  const TargetInstrInfo &TII = *MF.getTarget().getInstrInfo();
-  DebugLoc DL = I != MBB.end() ? I->getDebugLoc() : DebugLoc();
-  unsigned Mips16SPAliasReg = MipsFI->getMips16SPAliasReg();
-
-  BuildMI(MBB, I, DL, TII.get(Mips::MoveR3216), Mips16SPAliasReg)
-    .addReg(Mips::SP);
-}
-
-
-bool MipsDAGToDAGISel::ReplaceUsesWithZeroReg(MachineRegisterInfo *MRI,
-                                              const MachineInstr& MI) {
-  unsigned DstReg = 0, ZeroReg = 0;
-
-  // Check if MI is "addiu $dst, $zero, 0" or "daddiu $dst, $zero, 0".
-  if ((MI.getOpcode() == Mips::ADDiu) &&
-      (MI.getOperand(1).getReg() == Mips::ZERO) &&
-      (MI.getOperand(2).getImm() == 0)) {
-    DstReg = MI.getOperand(0).getReg();
-    ZeroReg = Mips::ZERO;
-  } else if ((MI.getOpcode() == Mips::DADDiu) &&
-             (MI.getOperand(1).getReg() == Mips::ZERO_64) &&
-             (MI.getOperand(2).getImm() == 0)) {
-    DstReg = MI.getOperand(0).getReg();
-    ZeroReg = Mips::ZERO_64;
-  }
-
-  if (!DstReg)
-    return false;
-
-  // Replace uses with ZeroReg.
-  for (MachineRegisterInfo::use_iterator U = MRI->use_begin(DstReg),
-       E = MRI->use_end(); U != E;) {
-    MachineOperand &MO = U.getOperand();
-    unsigned OpNo = U.getOperandNo();
-    MachineInstr *MI = MO.getParent();
-    ++U;
-
-    // Do not replace if it is a phi's operand or is tied to def operand.
-    if (MI->isPHI() || MI->isRegTiedToDefOperand(OpNo) || MI->isPseudo())
-      continue;
-
-    MO.setReg(ZeroReg);
-  }
-
-  return true;
-}
-
-void MipsDAGToDAGISel::ProcessFunctionAfterISel(MachineFunction &MF) {
-  InitGlobalBaseReg(MF);
-  InitMips16SPAliasReg(MF);
-
-  MachineRegisterInfo *MRI = &MF.getRegInfo();
-
-  for (MachineFunction::iterator MFI = MF.begin(), MFE = MF.end(); MFI != MFE;
-       ++MFI)
-    for (MachineBasicBlock::iterator I = MFI->begin(); I != MFI->end(); ++I)
-      ReplaceUsesWithZeroReg(MRI, *I);
-}
 
 bool MipsDAGToDAGISel::runOnMachineFunction(MachineFunction &MF) {
   bool Ret = SelectionDAGISel::runOnMachineFunction(MF);
 
-  ProcessFunctionAfterISel(MF);
+  processFunctionAfterISel(MF);
 
   return Ret;
 }
@@ -320,233 +61,36 @@ SDNode *MipsDAGToDAGISel::getGlobalBaseReg() {
   return CurDAG->getRegister(GlobalBaseReg, TLI.getPointerTy()).getNode();
 }
 
-/// getMips16SPAliasReg - Output the instructions required to put the
-/// SP into a Mips16 accessible aliased register.
-SDValue MipsDAGToDAGISel::getMips16SPAliasReg() {
-  unsigned Mips16SPAliasReg =
-    MF->getInfo<MipsFunctionInfo>()->getMips16SPAliasReg();
-  return CurDAG->getRegister(Mips16SPAliasReg, TLI.getPointerTy());
-}
-
 /// ComplexPattern used on MipsInstrInfo
 /// Used on Mips Load/Store instructions
 bool MipsDAGToDAGISel::selectAddrRegImm(SDValue Addr, SDValue &Base,
                                         SDValue &Offset) const {
-  EVT ValTy = Addr.getValueType();
-
-  // if Address is FI, get the TargetFrameIndex.
-  if (FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>(Addr)) {
-    Base   = CurDAG->getTargetFrameIndex(FIN->getIndex(), ValTy);
-    Offset = CurDAG->getTargetConstant(0, ValTy);
-    return true;
-  }
-
-  // on PIC code Load GA
-  if (Addr.getOpcode() == MipsISD::Wrapper) {
-    Base   = Addr.getOperand(0);
-    Offset = Addr.getOperand(1);
-    return true;
-  }
-
-  if (TM.getRelocationModel() != Reloc::PIC_) {
-    if ((Addr.getOpcode() == ISD::TargetExternalSymbol ||
-        Addr.getOpcode() == ISD::TargetGlobalAddress))
-      return false;
-  }
-
-  // Addresses of the form FI+const or FI|const
-  if (CurDAG->isBaseWithConstantOffset(Addr)) {
-    ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1));
-    if (isInt<16>(CN->getSExtValue())) {
-
-      // If the first operand is a FI, get the TargetFI Node
-      if (FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>
-                                  (Addr.getOperand(0)))
-        Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), ValTy);
-      else
-        Base = Addr.getOperand(0);
-
-      Offset = CurDAG->getTargetConstant(CN->getZExtValue(), ValTy);
-      return true;
-    }
-  }
-
-  // Operand is a result from an ADD.
-  if (Addr.getOpcode() == ISD::ADD) {
-    // When loading from constant pools, load the lower address part in
-    // the instruction itself. Example, instead of:
-    //  lui $2, %hi($CPI1_0)
-    //  addiu $2, $2, %lo($CPI1_0)
-    //  lwc1 $f0, 0($2)
-    // Generate:
-    //  lui $2, %hi($CPI1_0)
-    //  lwc1 $f0, %lo($CPI1_0)($2)
-    if (Addr.getOperand(1).getOpcode() == MipsISD::Lo ||
-        Addr.getOperand(1).getOpcode() == MipsISD::GPRel) {
-      SDValue Opnd0 = Addr.getOperand(1).getOperand(0);
-      if (isa<ConstantPoolSDNode>(Opnd0) || isa<GlobalAddressSDNode>(Opnd0) ||
-          isa<JumpTableSDNode>(Opnd0)) {
-        Base = Addr.getOperand(0);
-        Offset = Opnd0;
-        return true;
-      }
-    }
-  }
-
+  llvm_unreachable("Unimplemented function.");
   return false;
 }
 
 bool MipsDAGToDAGISel::selectAddrDefault(SDValue Addr, SDValue &Base,
                                          SDValue &Offset) const {
-  Base = Addr;
-  Offset = CurDAG->getTargetConstant(0, Addr.getValueType());
-  return true;
+  llvm_unreachable("Unimplemented function.");
+  return false;
 }
 
 bool MipsDAGToDAGISel::selectIntAddr(SDValue Addr, SDValue &Base,
                                      SDValue &Offset) const {
-  return selectAddrRegImm(Addr, Base, Offset) ||
-    selectAddrDefault(Addr, Base, Offset);
-}
-
-void MipsDAGToDAGISel::getMips16SPRefReg(SDNode *Parent, SDValue &AliasReg) {
-  SDValue AliasFPReg = CurDAG->getRegister(Mips::S0, TLI.getPointerTy());
-  if (Parent) {
-    switch (Parent->getOpcode()) {
-      case ISD::LOAD: {
-        LoadSDNode *SD = dyn_cast<LoadSDNode>(Parent);
-        switch (SD->getMemoryVT().getSizeInBits()) {
-        case 8:
-        case 16:
-          AliasReg = TM.getFrameLowering()->hasFP(*MF)?
-            AliasFPReg: getMips16SPAliasReg();
-          return;
-        }
-        break;
-      }
-      case ISD::STORE: {
-        StoreSDNode *SD = dyn_cast<StoreSDNode>(Parent);
-        switch (SD->getMemoryVT().getSizeInBits()) {
-        case 8:
-        case 16:
-          AliasReg = TM.getFrameLowering()->hasFP(*MF)?
-            AliasFPReg: getMips16SPAliasReg();
-          return;
-        }
-        break;
-      }
-    }
-  }
-  AliasReg = CurDAG->getRegister(Mips::SP, TLI.getPointerTy());
-  return;
-
-}
-bool MipsDAGToDAGISel::SelectAddr16(
-  SDNode *Parent, SDValue Addr, SDValue &Base, SDValue &Offset,
-  SDValue &Alias) {
-  EVT ValTy = Addr.getValueType();
-
-  Alias = CurDAG->getTargetConstant(0, ValTy);
-
-  // if Address is FI, get the TargetFrameIndex.
-  if (FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>(Addr)) {
-    Base   = CurDAG->getTargetFrameIndex(FIN->getIndex(), ValTy);
-    Offset = CurDAG->getTargetConstant(0, ValTy);
-    getMips16SPRefReg(Parent, Alias);
-    return true;
-  }
-  // on PIC code Load GA
-  if (Addr.getOpcode() == MipsISD::Wrapper) {
-    Base   = Addr.getOperand(0);
-    Offset = Addr.getOperand(1);
-    return true;
-  }
-  if (TM.getRelocationModel() != Reloc::PIC_) {
-    if ((Addr.getOpcode() == ISD::TargetExternalSymbol ||
-        Addr.getOpcode() == ISD::TargetGlobalAddress))
-      return false;
-  }
-  // Addresses of the form FI+const or FI|const
-  if (CurDAG->isBaseWithConstantOffset(Addr)) {
-    ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1));
-    if (isInt<16>(CN->getSExtValue())) {
-
-      // If the first operand is a FI, get the TargetFI Node
-      if (FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>
-                                  (Addr.getOperand(0))) {
-        Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), ValTy);
-        getMips16SPRefReg(Parent, Alias);
-      }
-      else
-        Base = Addr.getOperand(0);
-
-      Offset = CurDAG->getTargetConstant(CN->getZExtValue(), ValTy);
-      return true;
-    }
-  }
-  // Operand is a result from an ADD.
-  if (Addr.getOpcode() == ISD::ADD) {
-    // When loading from constant pools, load the lower address part in
-    // the instruction itself. Example, instead of:
-    //  lui $2, %hi($CPI1_0)
-    //  addiu $2, $2, %lo($CPI1_0)
-    //  lwc1 $f0, 0($2)
-    // Generate:
-    //  lui $2, %hi($CPI1_0)
-    //  lwc1 $f0, %lo($CPI1_0)($2)
-    if (Addr.getOperand(1).getOpcode() == MipsISD::Lo ||
-        Addr.getOperand(1).getOpcode() == MipsISD::GPRel) {
-      SDValue Opnd0 = Addr.getOperand(1).getOperand(0);
-      if (isa<ConstantPoolSDNode>(Opnd0) || isa<GlobalAddressSDNode>(Opnd0) ||
-          isa<JumpTableSDNode>(Opnd0)) {
-        Base = Addr.getOperand(0);
-        Offset = Opnd0;
-        return true;
-      }
-    }
-
-    // If an indexed floating point load/store can be emitted, return false.
-    const LSBaseSDNode *LS = dyn_cast<LSBaseSDNode>(Parent);
-
-    if (LS &&
-        (LS->getMemoryVT() == MVT::f32 || LS->getMemoryVT() == MVT::f64) &&
-        Subtarget.hasFPIdx())
-      return false;
-  }
-  Base   = Addr;
-  Offset = CurDAG->getTargetConstant(0, ValTy);
-  return true;
+  llvm_unreachable("Unimplemented function.");
+  return false;
 }
 
-/// Select multiply instructions.
-std::pair<SDNode*, SDNode*>
-MipsDAGToDAGISel::SelectMULT(SDNode *N, unsigned Opc, DebugLoc dl, EVT Ty,
-                             bool HasLo, bool HasHi) {
-  SDNode *Lo = 0, *Hi = 0;
-  SDNode *Mul = CurDAG->getMachineNode(Opc, dl, MVT::Glue, N->getOperand(0),
-                                       N->getOperand(1));
-  SDValue InFlag = SDValue(Mul, 0);
-
-  if (HasLo) {
-    unsigned Opcode = Subtarget.inMips16Mode() ? Mips::Mflo16 :
-      (Ty == MVT::i32 ? Mips::MFLO : Mips::MFLO64);
-    Lo = CurDAG->getMachineNode(Opcode, dl, Ty, MVT::Glue, InFlag);
-    InFlag = SDValue(Lo, 1);
-  }
-  if (HasHi) {
-    unsigned Opcode = Subtarget.inMips16Mode() ? Mips::Mfhi16 :
-      (Ty == MVT::i32 ? Mips::MFHI : Mips::MFHI64);
-    Hi = CurDAG->getMachineNode(Opcode, dl, Ty, InFlag);
-  }
-  return std::make_pair(Lo, Hi);
+bool MipsDAGToDAGISel::selectAddr16(SDNode *Parent, SDValue N, SDValue &Base,
+                                    SDValue &Offset, SDValue &Alias) {
+  llvm_unreachable("Unimplemented function.");
+  return false;
 }
 
-
 /// Select instructions not customized! Used for
 /// expanded, promoted and normal instructions
 SDNode* MipsDAGToDAGISel::Select(SDNode *Node) {
   unsigned Opcode = Node->getOpcode();
-  DebugLoc dl = Node->getDebugLoc();
 
   // Dump information about the Node being selected
   DEBUG(errs() << "Selecting: "; Node->dump(CurDAG); errs() << "\n");
@@ -557,167 +101,19 @@ SDNode* MipsDAGToDAGISel::Select(SDNode *Node) {
     return NULL;
   }
 
-  ///
-  // Instruction Selection not handled by the auto-generated
-  // tablegen selection should be handled here.
-  ///
-  EVT NodeTy = Node->getValueType(0);
-  unsigned MultOpc;
+  // See if subclasses can handle this node.
+  std::pair<bool, SDNode*> Ret = selectNode(Node);
+
+  if (Ret.first)
+    return Ret.second;
 
   switch(Opcode) {
   default: break;
 
-  case ISD::SUBE:
-  case ISD::ADDE: {
-    bool inMips16Mode = Subtarget.inMips16Mode();
-    SDValue InFlag = Node->getOperand(2), CmpLHS;
-    unsigned Opc = InFlag.getOpcode(); (void)Opc;
-    assert(((Opc == ISD::ADDC || Opc == ISD::ADDE) ||
-            (Opc == ISD::SUBC || Opc == ISD::SUBE)) &&
-           "(ADD|SUB)E flag operand must come from (ADD|SUB)C/E insn");
-
-    unsigned MOp;
-    if (Opcode == ISD::ADDE) {
-      CmpLHS = InFlag.getValue(0);
-      if (inMips16Mode)
-        MOp = Mips::AdduRxRyRz16;
-      else
-        MOp = Mips::ADDu;
-    } else {
-      CmpLHS = InFlag.getOperand(0);
-      if (inMips16Mode)
-        MOp = Mips::SubuRxRyRz16;
-      else
-        MOp = Mips::SUBu;
-    }
-
-    SDValue Ops[] = { CmpLHS, InFlag.getOperand(1) };
-
-    SDValue LHS = Node->getOperand(0);
-    SDValue RHS = Node->getOperand(1);
-
-    EVT VT = LHS.getValueType();
-
-    unsigned Sltu_op = inMips16Mode? Mips::SltuRxRyRz16: Mips::SLTu;
-    SDNode *Carry = CurDAG->getMachineNode(Sltu_op, dl, VT, Ops, 2);
-    unsigned Addu_op = inMips16Mode? Mips::AdduRxRyRz16 : Mips::ADDu;
-    SDNode *AddCarry = CurDAG->getMachineNode(Addu_op, dl, VT,
-                                              SDValue(Carry,0), RHS);
-
-    return CurDAG->SelectNodeTo(Node, MOp, VT, MVT::Glue,
-                                LHS, SDValue(AddCarry,0));
-  }
-
-  /// Mul with two results
-  case ISD::SMUL_LOHI:
-  case ISD::UMUL_LOHI: {
-    if (NodeTy == MVT::i32) {
-      if (Subtarget.inMips16Mode())
-        MultOpc = (Opcode == ISD::UMUL_LOHI ? Mips::MultuRxRy16 :
-                   Mips::MultRxRy16);
-      else
-        MultOpc = (Opcode == ISD::UMUL_LOHI ? Mips::MULTu : Mips::MULT);
-    }
-    else
-      MultOpc = (Opcode == ISD::UMUL_LOHI ? Mips::DMULTu : Mips::DMULT);
-
-    std::pair<SDNode*, SDNode*> LoHi = SelectMULT(Node, MultOpc, dl, NodeTy,
-                                                  true, true);
-
-    if (!SDValue(Node, 0).use_empty())
-      ReplaceUses(SDValue(Node, 0), SDValue(LoHi.first, 0));
-
-    if (!SDValue(Node, 1).use_empty())
-      ReplaceUses(SDValue(Node, 1), SDValue(LoHi.second, 0));
-
-    return NULL;
-  }
-
-  /// Special Muls
-  case ISD::MUL: {
-    // Mips32 has a 32-bit three operand mul instruction.
-    if (Subtarget.hasMips32() && NodeTy == MVT::i32)
-      break;
-    return SelectMULT(Node, NodeTy == MVT::i32 ? Mips::MULT : Mips::DMULT,
-                      dl, NodeTy, true, false).first;
-  }
-  case ISD::MULHS:
-  case ISD::MULHU: {
-    if (NodeTy == MVT::i32) {
-      if (Subtarget.inMips16Mode())
-        MultOpc = (Opcode == ISD::MULHU ?
-                   Mips::MultuRxRy16 : Mips::MultRxRy16);
-      else
-        MultOpc = (Opcode == ISD::MULHU ? Mips::MULTu : Mips::MULT);
-    }
-    else
-      MultOpc = (Opcode == ISD::MULHU ? Mips::DMULTu : Mips::DMULT);
-
-    return SelectMULT(Node, MultOpc, dl, NodeTy, false, true).second;
-  }
-
   // Get target GOT address.
   case ISD::GLOBAL_OFFSET_TABLE:
     return getGlobalBaseReg();
 
-  case ISD::ConstantFP: {
-    ConstantFPSDNode *CN = dyn_cast<ConstantFPSDNode>(Node);
-    if (Node->getValueType(0) == MVT::f64 && CN->isExactlyValue(+0.0)) {
-      if (Subtarget.hasMips64()) {
-        SDValue Zero = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), dl,
-                                              Mips::ZERO_64, MVT::i64);
-        return CurDAG->getMachineNode(Mips::DMTC1, dl, MVT::f64, Zero);
-      }
-
-      SDValue Zero = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), dl,
-                                            Mips::ZERO, MVT::i32);
-      return CurDAG->getMachineNode(Mips::BuildPairF64, dl, MVT::f64, Zero,
-                                    Zero);
-    }
-    break;
-  }
-
-  case ISD::Constant: {
-    const ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Node);
-    unsigned Size = CN->getValueSizeInBits(0);
-
-    if (Size == 32)
-      break;
-
-    MipsAnalyzeImmediate AnalyzeImm;
-    int64_t Imm = CN->getSExtValue();
-
-    const MipsAnalyzeImmediate::InstSeq &Seq =
-      AnalyzeImm.Analyze(Imm, Size, false);
-
-    MipsAnalyzeImmediate::InstSeq::const_iterator Inst = Seq.begin();
-    DebugLoc DL = CN->getDebugLoc();
-    SDNode *RegOpnd;
-    SDValue ImmOpnd = CurDAG->getTargetConstant(SignExtend64<16>(Inst->ImmOpnd),
-                                                MVT::i64);
-
-    // The first instruction can be a LUi which is different from other
-    // instructions (ADDiu, ORI and SLL) in that it does not have a register
-    // operand.
-    if (Inst->Opc == Mips::LUi64)
-      RegOpnd = CurDAG->getMachineNode(Inst->Opc, DL, MVT::i64, ImmOpnd);
-    else
-      RegOpnd =
-        CurDAG->getMachineNode(Inst->Opc, DL, MVT::i64,
-                               CurDAG->getRegister(Mips::ZERO_64, MVT::i64),
-                               ImmOpnd);
-
-    // The remaining instructions in the sequence are handled here.
-    for (++Inst; Inst != Seq.end(); ++Inst) {
-      ImmOpnd = CurDAG->getTargetConstant(SignExtend64<16>(Inst->ImmOpnd),
-                                          MVT::i64);
-      RegOpnd = CurDAG->getMachineNode(Inst->Opc, DL, MVT::i64,
-                                       SDValue(RegOpnd, 0), ImmOpnd);
-    }
-
-    return RegOpnd;
-  }
-
 #ifndef NDEBUG
   case ISD::LOAD:
   case ISD::STORE:
@@ -726,31 +122,6 @@ SDNode* MipsDAGToDAGISel::Select(SDNode *Node) {
            "Unexpected unaligned loads/stores.");
     break;
 #endif
-
-  case MipsISD::ThreadPointer: {
-    EVT PtrVT = TLI.getPointerTy();
-    unsigned RdhwrOpc, SrcReg, DestReg;
-
-    if (PtrVT == MVT::i32) {
-      RdhwrOpc = Mips::RDHWR;
-      SrcReg = Mips::HWR29;
-      DestReg = Mips::V1;
-    } else {
-      RdhwrOpc = Mips::RDHWR64;
-      SrcReg = Mips::HWR29_64;
-      DestReg = Mips::V1_64;
-    }
-
-    SDNode *Rdhwr =
-      CurDAG->getMachineNode(RdhwrOpc, Node->getDebugLoc(),
-                             Node->getValueType(0),
-                             CurDAG->getRegister(SrcReg, PtrVT));
-    SDValue Chain = CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, DestReg,
-                                         SDValue(Rdhwr, 0));
-    SDValue ResNode = CurDAG->getCopyFromReg(Chain, dl, DestReg, PtrVT);
-    ReplaceUses(SDValue(Node, 0), ResNode);
-    return ResNode.getNode();
-  }
   }
 
   // Select the default instruction
@@ -776,5 +147,8 @@ SelectInlineAsmMemoryOperand(const SDValue &Op, char ConstraintCode,
 /// createMipsISelDag - This pass converts a legalized DAG into a
 /// MIPS-specific DAG, ready for instruction scheduling.
 FunctionPass *llvm::createMipsISelDag(MipsTargetMachine &TM) {
-  return new MipsDAGToDAGISel(TM);
+  if (TM.getSubtargetImpl()->inMips16Mode())
+    return llvm::createMips16ISelDag(TM);
+
+  return llvm::createMipsSEISelDag(TM);
 }