1 files changed, 665 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/ARM/ARMFastISel.cpp b/contrib/llvm/lib/Target/ARM/ARMFastISel.cpp
new file mode 100644
index 0000000..4892eae
--- /dev/null
+++ b/contrib/llvm/lib/Target/ARM/ARMFastISel.cpp
@@ -0,0 +1,665 @@
+//===-- ARMFastISel.cpp - ARM FastISel implementation ---------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file defines the ARM-specific support for the FastISel class. Some
+// of the target-specific code is generated by tablegen in the file
+// ARMGenFastISel.inc, which is #included here.
+//
+//===----------------------------------------------------------------------===//
+
+#include "ARM.h"
+#include "ARMBaseInstrInfo.h"
+#include "ARMRegisterInfo.h"
+#include "ARMTargetMachine.h"
+#include "ARMSubtarget.h"
+#include "llvm/CallingConv.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/GlobalVariable.h"
+#include "llvm/Instructions.h"
+#include "llvm/IntrinsicInst.h"
+#include "llvm/CodeGen/Analysis.h"
+#include "llvm/CodeGen/FastISel.h"
+#include "llvm/CodeGen/FunctionLoweringInfo.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachineConstantPool.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/Support/CallSite.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/GetElementPtrTypeIterator.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/Target/TargetInstrInfo.h"
+#include "llvm/Target/TargetLowering.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetOptions.h"
+using namespace llvm;
+
+static cl::opt<bool>
+EnableARMFastISel("arm-fast-isel",
+                  cl::desc("Turn on experimental ARM fast-isel support"),
+                  cl::init(false), cl::Hidden);
+
+namespace {
+
+class ARMFastISel : public FastISel {
+
+  /// Subtarget - Keep a pointer to the ARMSubtarget around so that we can
+  /// make the right decision when generating code for different targets.
+  const ARMSubtarget *Subtarget;
+  const TargetMachine &TM;
+  const TargetInstrInfo &TII;
+  const TargetLowering &TLI;
+  const ARMFunctionInfo *AFI;
+
+  // Convenience variable to avoid checking all the time.
+  bool isThumb;
+
+  public:
+    explicit ARMFastISel(FunctionLoweringInfo &funcInfo) 
+    : FastISel(funcInfo),
+      TM(funcInfo.MF->getTarget()),
+      TII(*TM.getInstrInfo()),
+      TLI(*TM.getTargetLowering()) {
+      Subtarget = &TM.getSubtarget<ARMSubtarget>();
+      AFI = funcInfo.MF->getInfo<ARMFunctionInfo>();
+      isThumb = AFI->isThumbFunction();
+    }
+
+    // Code from FastISel.cpp.
+    virtual unsigned FastEmitInst_(unsigned MachineInstOpcode,
+                                   const TargetRegisterClass *RC);
+    virtual unsigned FastEmitInst_r(unsigned MachineInstOpcode,
+                                    const TargetRegisterClass *RC,
+                                    unsigned Op0, bool Op0IsKill);
+    virtual unsigned FastEmitInst_rr(unsigned MachineInstOpcode,
+                                     const TargetRegisterClass *RC,
+                                     unsigned Op0, bool Op0IsKill,
+                                     unsigned Op1, bool Op1IsKill);
+    virtual unsigned FastEmitInst_ri(unsigned MachineInstOpcode,
+                                     const TargetRegisterClass *RC,
+                                     unsigned Op0, bool Op0IsKill,
+                                     uint64_t Imm);
+    virtual unsigned FastEmitInst_rf(unsigned MachineInstOpcode,
+                                     const TargetRegisterClass *RC,
+                                     unsigned Op0, bool Op0IsKill,
+                                     const ConstantFP *FPImm);
+    virtual unsigned FastEmitInst_i(unsigned MachineInstOpcode,
+                                    const TargetRegisterClass *RC,
+                                    uint64_t Imm);
+    virtual unsigned FastEmitInst_rri(unsigned MachineInstOpcode,
+                                      const TargetRegisterClass *RC,
+                                      unsigned Op0, bool Op0IsKill,
+                                      unsigned Op1, bool Op1IsKill,
+                                      uint64_t Imm);
+    virtual unsigned FastEmitInst_extractsubreg(MVT RetVT,
+                                                unsigned Op0, bool Op0IsKill,
+                                                uint32_t Idx);
+                                                
+    // Backend specific FastISel code.
+    virtual bool TargetSelectInstruction(const Instruction *I);
+    virtual unsigned TargetMaterializeConstant(const Constant *C);
+
+  #include "ARMGenFastISel.inc"
+  
+    // Instruction selection routines.
+    virtual bool ARMSelectLoad(const Instruction *I);
+    virtual bool ARMSelectStore(const Instruction *I);
+    virtual bool ARMSelectBranch(const Instruction *I);
+
+    // Utility routines.
+  private:
+    bool isTypeLegal(const Type *Ty, EVT &VT);
+    bool isLoadTypeLegal(const Type *Ty, EVT &VT);
+    bool ARMEmitLoad(EVT VT, unsigned &ResultReg, unsigned Reg, int Offset);
+    bool ARMEmitStore(EVT VT, unsigned SrcReg, unsigned Reg, int Offset);
+    bool ARMLoadAlloca(const Instruction *I);
+    bool ARMStoreAlloca(const Instruction *I, unsigned SrcReg);
+    bool ARMComputeRegOffset(const Value *Obj, unsigned &Reg, int &Offset);
+    bool ARMMaterializeConstant(const ConstantInt *Val, unsigned &Reg);
+    
+    bool DefinesOptionalPredicate(MachineInstr *MI, bool *CPSR);
+    const MachineInstrBuilder &AddOptionalDefs(const MachineInstrBuilder &MIB);
+};
+
+} // end anonymous namespace
+
+// #include "ARMGenCallingConv.inc"
+
+// DefinesOptionalPredicate - This is different from DefinesPredicate in that
+// we don't care about implicit defs here, just places we'll need to add a
+// default CCReg argument. Sets CPSR if we're setting CPSR instead of CCR.
+bool ARMFastISel::DefinesOptionalPredicate(MachineInstr *MI, bool *CPSR) {
+  const TargetInstrDesc &TID = MI->getDesc();
+  if (!TID.hasOptionalDef())
+    return false;
+
+  // Look to see if our OptionalDef is defining CPSR or CCR.
+  for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) {
+    const MachineOperand &MO = MI->getOperand(i);
+    if (!MO.isReg() || !MO.isDef()) continue;
+    if (MO.getReg() == ARM::CPSR)
+      *CPSR = true;
+  }
+  return true;
+}
+
+// If the machine is predicable go ahead and add the predicate operands, if
+// it needs default CC operands add those.
+const MachineInstrBuilder &
+ARMFastISel::AddOptionalDefs(const MachineInstrBuilder &MIB) {
+  MachineInstr *MI = &*MIB;
+
+  // Do we use a predicate?
+  if (TII.isPredicable(MI))
+    AddDefaultPred(MIB);
+  
+  // Do we optionally set a predicate?  Preds is size > 0 iff the predicate
+  // defines CPSR. All other OptionalDefines in ARM are the CCR register.
+  bool CPSR = false;
+  if (DefinesOptionalPredicate(MI, &CPSR)) {
+    if (CPSR)
+      AddDefaultT1CC(MIB);
+    else
+      AddDefaultCC(MIB);
+  }
+  return MIB;
+}
+
+unsigned ARMFastISel::FastEmitInst_(unsigned MachineInstOpcode,
+                                    const TargetRegisterClass* RC) {
+  unsigned ResultReg = createResultReg(RC);
+  const TargetInstrDesc &II = TII.get(MachineInstOpcode);
+
+  AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg));
+  return ResultReg;
+}
+
+unsigned ARMFastISel::FastEmitInst_r(unsigned MachineInstOpcode,
+                                     const TargetRegisterClass *RC,
+                                     unsigned Op0, bool Op0IsKill) {
+  unsigned ResultReg = createResultReg(RC);
+  const TargetInstrDesc &II = TII.get(MachineInstOpcode);
+
+  if (II.getNumDefs() >= 1)
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+                   .addReg(Op0, Op0IsKill * RegState::Kill));
+  else {
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+                   .addReg(Op0, Op0IsKill * RegState::Kill));
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                   TII.get(TargetOpcode::COPY), ResultReg)
+                   .addReg(II.ImplicitDefs[0]));
+  }
+  return ResultReg;
+}
+
+unsigned ARMFastISel::FastEmitInst_rr(unsigned MachineInstOpcode,
+                                      const TargetRegisterClass *RC,
+                                      unsigned Op0, bool Op0IsKill,
+                                      unsigned Op1, bool Op1IsKill) {
+  unsigned ResultReg = createResultReg(RC);
+  const TargetInstrDesc &II = TII.get(MachineInstOpcode);
+
+  if (II.getNumDefs() >= 1)
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+                   .addReg(Op0, Op0IsKill * RegState::Kill)
+                   .addReg(Op1, Op1IsKill * RegState::Kill));
+  else {
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+                   .addReg(Op0, Op0IsKill * RegState::Kill)
+                   .addReg(Op1, Op1IsKill * RegState::Kill));
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                           TII.get(TargetOpcode::COPY), ResultReg)
+                   .addReg(II.ImplicitDefs[0]));
+  }
+  return ResultReg;
+}
+
+unsigned ARMFastISel::FastEmitInst_ri(unsigned MachineInstOpcode,
+                                      const TargetRegisterClass *RC,
+                                      unsigned Op0, bool Op0IsKill,
+                                      uint64_t Imm) {
+  unsigned ResultReg = createResultReg(RC);
+  const TargetInstrDesc &II = TII.get(MachineInstOpcode);
+
+  if (II.getNumDefs() >= 1)
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+                   .addReg(Op0, Op0IsKill * RegState::Kill)
+                   .addImm(Imm));
+  else {
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+                   .addReg(Op0, Op0IsKill * RegState::Kill)
+                   .addImm(Imm));
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                           TII.get(TargetOpcode::COPY), ResultReg)
+                   .addReg(II.ImplicitDefs[0]));
+  }
+  return ResultReg;
+}
+
+unsigned ARMFastISel::FastEmitInst_rf(unsigned MachineInstOpcode,
+                                      const TargetRegisterClass *RC,
+                                      unsigned Op0, bool Op0IsKill,
+                                      const ConstantFP *FPImm) {
+  unsigned ResultReg = createResultReg(RC);
+  const TargetInstrDesc &II = TII.get(MachineInstOpcode);
+
+  if (II.getNumDefs() >= 1)
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+                   .addReg(Op0, Op0IsKill * RegState::Kill)
+                   .addFPImm(FPImm));
+  else {
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+                   .addReg(Op0, Op0IsKill * RegState::Kill)
+                   .addFPImm(FPImm));
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                           TII.get(TargetOpcode::COPY), ResultReg)
+                   .addReg(II.ImplicitDefs[0]));
+  }
+  return ResultReg;
+}
+
+unsigned ARMFastISel::FastEmitInst_rri(unsigned MachineInstOpcode,
+                                       const TargetRegisterClass *RC,
+                                       unsigned Op0, bool Op0IsKill,
+                                       unsigned Op1, bool Op1IsKill,
+                                       uint64_t Imm) {
+  unsigned ResultReg = createResultReg(RC);
+  const TargetInstrDesc &II = TII.get(MachineInstOpcode);
+
+  if (II.getNumDefs() >= 1)
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+                   .addReg(Op0, Op0IsKill * RegState::Kill)
+                   .addReg(Op1, Op1IsKill * RegState::Kill)
+                   .addImm(Imm));
+  else {
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+                   .addReg(Op0, Op0IsKill * RegState::Kill)
+                   .addReg(Op1, Op1IsKill * RegState::Kill)
+                   .addImm(Imm));
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                           TII.get(TargetOpcode::COPY), ResultReg)
+                   .addReg(II.ImplicitDefs[0]));
+  }
+  return ResultReg;
+}
+
+unsigned ARMFastISel::FastEmitInst_i(unsigned MachineInstOpcode,
+                                     const TargetRegisterClass *RC,
+                                     uint64_t Imm) {
+  unsigned ResultReg = createResultReg(RC);
+  const TargetInstrDesc &II = TII.get(MachineInstOpcode);
+  
+  if (II.getNumDefs() >= 1)
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II, ResultReg)
+                   .addImm(Imm));
+  else {
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, II)
+                   .addImm(Imm));
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                           TII.get(TargetOpcode::COPY), ResultReg)
+                   .addReg(II.ImplicitDefs[0]));
+  }
+  return ResultReg;
+}
+
+unsigned ARMFastISel::FastEmitInst_extractsubreg(MVT RetVT,
+                                                 unsigned Op0, bool Op0IsKill,
+                                                 uint32_t Idx) {
+  unsigned ResultReg = createResultReg(TLI.getRegClassFor(RetVT));
+  assert(TargetRegisterInfo::isVirtualRegister(Op0) &&
+         "Cannot yet extract from physregs");
+  AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt,
+                         DL, TII.get(TargetOpcode::COPY), ResultReg)
+                 .addReg(Op0, getKillRegState(Op0IsKill), Idx));
+  return ResultReg;
+}
+
+unsigned ARMFastISel::TargetMaterializeConstant(const Constant *C) {
+  EVT VT = TLI.getValueType(C->getType(), true);
+
+  // Only handle simple types.
+  if (!VT.isSimple()) return 0;
+  
+  // TODO: This should be safe for fp because they're just bits from the
+  // Constant.
+  // TODO: Theoretically we could materialize fp constants with instructions
+  // from VFP3.
+
+  // MachineConstantPool wants an explicit alignment.
+  unsigned Align = TD.getPrefTypeAlignment(C->getType());
+  if (Align == 0) {
+    // TODO: Figure out if this is correct.
+    Align = TD.getTypeAllocSize(C->getType());
+  }
+  unsigned Idx = MCP.getConstantPoolIndex(C, Align);
+
+  unsigned DestReg = createResultReg(TLI.getRegClassFor(VT));
+  // Different addressing modes between ARM/Thumb2 for constant pool loads.
+  if (isThumb)
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                            TII.get(ARM::t2LDRpci))
+                    .addReg(DestReg).addConstantPoolIndex(Idx));
+  else
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                            TII.get(ARM::LDRcp))
+                    .addReg(DestReg).addConstantPoolIndex(Idx)
+                    .addReg(0).addImm(0));
+    
+  return DestReg;
+}
+
+bool ARMFastISel::isTypeLegal(const Type *Ty, EVT &VT) {
+  VT = TLI.getValueType(Ty, true);
+  
+  // Only handle simple types.
+  if (VT == MVT::Other || !VT.isSimple()) return false;
+    
+  // Handle all legal types, i.e. a register that will directly hold this
+  // value.
+  return TLI.isTypeLegal(VT);
+}
+
+bool ARMFastISel::isLoadTypeLegal(const Type *Ty, EVT &VT) {
+  if (isTypeLegal(Ty, VT)) return true;
+  
+  // If this is a type than can be sign or zero-extended to a basic operation
+  // go ahead and accept it now.
+  if (VT == MVT::i8 || VT == MVT::i16)
+    return true;
+  
+  return false;
+}
+
+// Computes the Reg+Offset to get to an object.
+bool ARMFastISel::ARMComputeRegOffset(const Value *Obj, unsigned &Reg,
+                                      int &Offset) {
+  // Some boilerplate from the X86 FastISel.
+  const User *U = NULL;
+  unsigned Opcode = Instruction::UserOp1;
+  if (const Instruction *I = dyn_cast<Instruction>(Obj)) {
+    // Don't walk into other basic blocks; it's possible we haven't
+    // visited them yet, so the instructions may not yet be assigned
+    // virtual registers.
+    if (FuncInfo.MBBMap[I->getParent()] != FuncInfo.MBB)
+      return false;
+
+    Opcode = I->getOpcode();
+    U = I;
+  } else if (const ConstantExpr *C = dyn_cast<ConstantExpr>(Obj)) {
+    Opcode = C->getOpcode();
+    U = C;
+  }
+
+  if (const PointerType *Ty = dyn_cast<PointerType>(Obj->getType()))
+    if (Ty->getAddressSpace() > 255)
+      // Fast instruction selection doesn't support the special
+      // address spaces.
+      return false;
+  
+  switch (Opcode) {
+    default: 
+    //errs() << "Failing Opcode is: " << *Op1 << "\n";
+    break;
+    case Instruction::Alloca: {
+      assert(false && "Alloca should have been handled earlier!");
+      return false;
+    }
+  }
+  
+  if (const GlobalValue *GV = dyn_cast<GlobalValue>(Obj)) {
+    //errs() << "Failing GV is: " << GV << "\n";
+    (void)GV;
+    return false;
+  }
+  
+  // Try to get this in a register if nothing else has worked.
+  Reg = getRegForValue(Obj);
+  if (Reg == 0) return false;
+
+  // Since the offset may be too large for the load instruction
+  // get the reg+offset into a register.
+  // TODO: Verify the additions work, otherwise we'll need to add the
+  // offset instead of 0 to the instructions and do all sorts of operand
+  // munging.
+  // TODO: Optimize this somewhat.
+  if (Offset != 0) {
+    ARMCC::CondCodes Pred = ARMCC::AL;
+    unsigned PredReg = 0;
+
+    if (!isThumb)
+      emitARMRegPlusImmediate(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                              Reg, Reg, Offset, Pred, PredReg,
+                              static_cast<const ARMBaseInstrInfo&>(TII));
+    else {
+      assert(AFI->isThumb2Function());
+      emitT2RegPlusImmediate(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                             Reg, Reg, Offset, Pred, PredReg,
+                             static_cast<const ARMBaseInstrInfo&>(TII));
+    }
+  }
+  
+  return true;
+}
+
+bool ARMFastISel::ARMLoadAlloca(const Instruction *I) {
+  Value *Op0 = I->getOperand(0);
+
+  // Verify it's an alloca.
+  if (const AllocaInst *AI = dyn_cast<AllocaInst>(Op0)) {
+    DenseMap<const AllocaInst*, int>::iterator SI =
+      FuncInfo.StaticAllocaMap.find(AI);
+
+    if (SI != FuncInfo.StaticAllocaMap.end()) {
+      TargetRegisterClass* RC = TLI.getRegClassFor(TLI.getPointerTy());
+      unsigned ResultReg = createResultReg(RC);
+      TII.loadRegFromStackSlot(*FuncInfo.MBB, *FuncInfo.InsertPt,
+                               ResultReg, SI->second, RC,
+                               TM.getRegisterInfo());
+      UpdateValueMap(I, ResultReg);
+      return true;
+    }
+  }
+  return false;
+}
+
+bool ARMFastISel::ARMEmitLoad(EVT VT, unsigned &ResultReg,
+                              unsigned Reg, int Offset) {
+  
+  assert(VT.isSimple() && "Non-simple types are invalid here!");
+  unsigned Opc;
+  
+  switch (VT.getSimpleVT().SimpleTy) {
+    default: 
+      assert(false && "Trying to emit for an unhandled type!");
+      return false;
+    case MVT::i16:
+      Opc = isThumb ? ARM::tLDRH : ARM::LDRH;
+      VT = MVT::i32;
+      break;
+    case MVT::i8:
+      Opc = isThumb ? ARM::tLDRB : ARM::LDRB;
+      VT = MVT::i32;
+      break;
+    case MVT::i32:
+      Opc = isThumb ? ARM::tLDR : ARM::LDR;
+      break;
+  }
+  
+  ResultReg = createResultReg(TLI.getRegClassFor(VT));
+  
+  // TODO: Fix the Addressing modes so that these can share some code.
+  // Since this is a Thumb1 load this will work in Thumb1 or 2 mode.
+  if (isThumb)
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                            TII.get(Opc), ResultReg)
+                    .addReg(Reg).addImm(Offset).addReg(0));
+  else
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                            TII.get(Opc), ResultReg)
+                    .addReg(Reg).addReg(0).addImm(Offset));
+                    
+  return true;
+}
+
+bool ARMFastISel::ARMStoreAlloca(const Instruction *I, unsigned SrcReg) {
+  Value *Op1 = I->getOperand(1);
+
+  // Verify it's an alloca.
+  if (const AllocaInst *AI = dyn_cast<AllocaInst>(Op1)) {
+    DenseMap<const AllocaInst*, int>::iterator SI =
+      FuncInfo.StaticAllocaMap.find(AI);
+
+    if (SI != FuncInfo.StaticAllocaMap.end()) {
+      TargetRegisterClass* RC = TLI.getRegClassFor(TLI.getPointerTy());
+      assert(SrcReg != 0 && "Nothing to store!");
+      TII.storeRegToStackSlot(*FuncInfo.MBB, *FuncInfo.InsertPt,
+                              SrcReg, true /*isKill*/, SI->second, RC,
+                              TM.getRegisterInfo());
+      return true;
+    }
+  }
+  return false;
+}
+
+bool ARMFastISel::ARMEmitStore(EVT VT, unsigned SrcReg,
+                               unsigned DstReg, int Offset) {
+  unsigned StrOpc;
+  switch (VT.getSimpleVT().SimpleTy) {
+    default: return false;
+    case MVT::i1:
+    case MVT::i8: StrOpc = isThumb ? ARM::tSTRB : ARM::STRB; break;
+    case MVT::i16: StrOpc = isThumb ? ARM::tSTRH : ARM::STRH; break;
+    case MVT::i32: StrOpc = isThumb ? ARM::tSTR : ARM::STR; break;
+    case MVT::f32:
+      if (!Subtarget->hasVFP2()) return false;
+      StrOpc = ARM::VSTRS;
+      break;
+    case MVT::f64:
+      if (!Subtarget->hasVFP2()) return false;
+      StrOpc = ARM::VSTRD;
+      break;
+  }
+  
+  if (isThumb)
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                            TII.get(StrOpc), SrcReg)
+                    .addReg(DstReg).addImm(Offset).addReg(0));
+  else
+    AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL,
+                            TII.get(StrOpc), SrcReg)
+                    .addReg(DstReg).addReg(0).addImm(Offset));
+  
+  return true;
+}
+
+bool ARMFastISel::ARMSelectStore(const Instruction *I) {
+  Value *Op0 = I->getOperand(0);
+  unsigned SrcReg = 0;
+
+  // Yay type legalization
+  EVT VT;
+  if (!isLoadTypeLegal(I->getOperand(0)->getType(), VT))
+    return false;
+
+  // Get the value to be stored into a register.
+  SrcReg = getRegForValue(Op0);
+  if (SrcReg == 0)
+    return false;
+    
+  // If we're an alloca we know we have a frame index and can emit the store
+  // quickly.
+  if (ARMStoreAlloca(I, SrcReg))
+    return true;
+    
+  // Our register and offset with innocuous defaults.
+  unsigned Reg = 0;
+  int Offset = 0;
+  
+  // See if we can handle this as Reg + Offset
+  if (!ARMComputeRegOffset(I->getOperand(1), Reg, Offset))
+    return false;
+    
+  if (!ARMEmitStore(VT, SrcReg, Reg, Offset /* 0 */)) return false;
+    
+  return false;
+  
+}
+
+bool ARMFastISel::ARMSelectLoad(const Instruction *I) {
+  // If we're an alloca we know we have a frame index and can emit the load
+  // directly in short order.
+  if (ARMLoadAlloca(I))
+    return true;
+    
+  // Verify we have a legal type before going any further.
+  EVT VT;
+  if (!isLoadTypeLegal(I->getType(), VT))
+    return false;
+  
+  // Our register and offset with innocuous defaults.
+  unsigned Reg = 0;
+  int Offset = 0;
+  
+  // See if we can handle this as Reg + Offset
+  if (!ARMComputeRegOffset(I->getOperand(0), Reg, Offset))
+    return false;
+  
+  unsigned ResultReg;
+  if (!ARMEmitLoad(VT, ResultReg, Reg, Offset /* 0 */)) return false;
+  
+  UpdateValueMap(I, ResultReg);
+  return true;
+}
+
+bool ARMFastISel::ARMSelectBranch(const Instruction *I) {
+  const BranchInst *BI = cast<BranchInst>(I);
+  MachineBasicBlock *TBB = FuncInfo.MBBMap[BI->getSuccessor(0)];
+  MachineBasicBlock *FBB = FuncInfo.MBBMap[BI->getSuccessor(1)];
+  
+  // Simple branch support.
+  unsigned CondReg = getRegForValue(BI->getCondition());
+  if (CondReg == 0) return false;
+  
+  unsigned CmpOpc = isThumb ? ARM::t2CMPrr : ARM::CMPrr;
+  unsigned BrOpc = isThumb ? ARM::t2Bcc : ARM::Bcc;
+  AddOptionalDefs(BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(CmpOpc))
+                  .addReg(CondReg).addReg(CondReg));
+  BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, TII.get(BrOpc))
+                  .addMBB(TBB).addImm(ARMCC::NE).addReg(ARM::CPSR);
+  FastEmitBranch(FBB, DL);
+  FuncInfo.MBB->addSuccessor(TBB);
+  return true;
+}
+
+// TODO: SoftFP support.
+bool ARMFastISel::TargetSelectInstruction(const Instruction *I) {
+  // No Thumb-1 for now.
+  if (isThumb && !AFI->isThumb2Function()) return false;
+  
+  switch (I->getOpcode()) {
+    case Instruction::Load:
+      return ARMSelectLoad(I);
+    case Instruction::Store:
+      return ARMSelectStore(I);
+    case Instruction::Br:
+      return ARMSelectBranch(I);
+    default: break;
+  }
+  return false;
+}
+
+namespace llvm {
+  llvm::FastISel *ARM::createFastISel(FunctionLoweringInfo &funcInfo) {
+    if (EnableARMFastISel) return new ARMFastISel(funcInfo);
+    return 0;
+  }
+}