Initial revision


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@14283 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PowerPCISelSimple.cpp b/lib/Target/PowerPC/PowerPCISelSimple.cpp
new file mode 100644
index 0000000..c9c0e2d
--- /dev/null
+++ b/lib/Target/PowerPC/PowerPCISelSimple.cpp
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+//===-- InstSelectSimple.cpp - A simple instruction selector for PowerPC --===//
+// 
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by the LLVM research group and is distributed under
+// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// 
+//===----------------------------------------------------------------------===//
+
+#include "PowerPC.h"
+#include "PowerPCInstrBuilder.h"
+#include "PowerPCInstrInfo.h"
+#include "llvm/Constants.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/Function.h"
+#include "llvm/Instructions.h"
+#include "llvm/IntrinsicLowering.h"
+#include "llvm/Pass.h"
+#include "llvm/CodeGen/MachineConstantPool.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/SSARegMap.h"
+#include "llvm/Target/MRegisterInfo.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Support/GetElementPtrTypeIterator.h"
+#include "llvm/Support/InstVisitor.h"
+using namespace llvm;
+
+namespace {
+  /// TypeClass - Used by the PowerPC backend to group LLVM types by their basic PPC
+  /// Representation.
+  ///
+  enum TypeClass {
+    cByte, cShort, cInt, cFP, cLong
+  };
+}
+
+/// getClass - Turn a primitive type into a "class" number which is based on the
+/// size of the type, and whether or not it is floating point.
+///
+static inline TypeClass getClass(const Type *Ty) {
+  switch (Ty->getPrimitiveID()) {
+  case Type::SByteTyID:
+  case Type::UByteTyID:   return cByte;      // Byte operands are class #0
+  case Type::ShortTyID:
+  case Type::UShortTyID:  return cShort;     // Short operands are class #1
+  case Type::IntTyID:
+  case Type::UIntTyID:
+  case Type::PointerTyID: return cInt;       // Int's and pointers are class #2
+
+  case Type::FloatTyID:
+  case Type::DoubleTyID:  return cFP;        // Floating Point is #3
+
+  case Type::LongTyID:
+  case Type::ULongTyID:   return cLong;      // Longs are class #4
+  default:
+    assert(0 && "Invalid type to getClass!");
+    return cByte;  // not reached
+  }
+}
+
+// getClassB - Just like getClass, but treat boolean values as ints.
+static inline TypeClass getClassB(const Type *Ty) {
+  if (Ty == Type::BoolTy) return cInt;
+  return getClass(Ty);
+}
+
+namespace {
+  struct ISel : public FunctionPass, InstVisitor<ISel> {
+    TargetMachine &TM;
+    MachineFunction *F;                 // The function we are compiling into
+    MachineBasicBlock *BB;              // The current MBB we are compiling
+    int VarArgsFrameIndex;              // FrameIndex for start of varargs area
+    int ReturnAddressIndex;             // FrameIndex for the return address
+
+    std::map<Value*, unsigned> RegMap;  // Mapping between Val's and SSA Regs
+
+    // MBBMap - Mapping between LLVM BB -> Machine BB
+    std::map<const BasicBlock*, MachineBasicBlock*> MBBMap;
+
+    // AllocaMap - Mapping from fixed sized alloca instructions to the
+    // FrameIndex for the alloca.
+    std::map<AllocaInst*, unsigned> AllocaMap;
+
+    ISel(TargetMachine &tm) : TM(tm), F(0), BB(0) {}
+
+    /// runOnFunction - Top level implementation of instruction selection for
+    /// the entire function.
+    ///
+    bool runOnFunction(Function &Fn) {
+      // First pass over the function, lower any unknown intrinsic functions
+      // with the IntrinsicLowering class.
+      LowerUnknownIntrinsicFunctionCalls(Fn);
+
+      F = &MachineFunction::construct(&Fn, TM);
+
+      // Create all of the machine basic blocks for the function...
+      for (Function::iterator I = Fn.begin(), E = Fn.end(); I != E; ++I)
+        F->getBasicBlockList().push_back(MBBMap[I] = new MachineBasicBlock(I));
+
+      BB = &F->front();
+
+      // Set up a frame object for the return address.  This is used by the
+      // llvm.returnaddress & llvm.frameaddress intrinisics.
+      ReturnAddressIndex = F->getFrameInfo()->CreateFixedObject(4, -4);
+
+      // Copy incoming arguments off of the stack...
+      LoadArgumentsToVirtualRegs(Fn);
+
+      // Instruction select everything except PHI nodes
+      visit(Fn);
+
+      // Select the PHI nodes
+      SelectPHINodes();
+
+      RegMap.clear();
+      MBBMap.clear();
+      AllocaMap.clear();
+      F = 0;
+      // We always build a machine code representation for the function
+      return true;
+    }
+
+    virtual const char *getPassName() const {
+      return "PowerPC Simple Instruction Selection";
+    }
+
+    /// visitBasicBlock - This method is called when we are visiting a new basic
+    /// block.  This simply creates a new MachineBasicBlock to emit code into
+    /// and adds it to the current MachineFunction.  Subsequent visit* for
+    /// instructions will be invoked for all instructions in the basic block.
+    ///
+    void visitBasicBlock(BasicBlock &LLVM_BB) {
+      BB = MBBMap[&LLVM_BB];
+    }
+
+    /// LowerUnknownIntrinsicFunctionCalls - This performs a prepass over the
+    /// function, lowering any calls to unknown intrinsic functions into the
+    /// equivalent LLVM code.
+    ///
+    void LowerUnknownIntrinsicFunctionCalls(Function &F);
+
+    /// LoadArgumentsToVirtualRegs - Load all of the arguments to this function
+    /// from the stack into virtual registers.
+    ///
+    void LoadArgumentsToVirtualRegs(Function &F);
+
+    /// SelectPHINodes - Insert machine code to generate phis.  This is tricky
+    /// because we have to generate our sources into the source basic blocks,
+    /// not the current one.
+    ///
+    void SelectPHINodes();
+
+    // Visitation methods for various instructions.  These methods simply emit
+    // fixed PowerPC code for each instruction.
+
+    // Control flow operators
+    void visitReturnInst(ReturnInst &RI);
+    void visitBranchInst(BranchInst &BI);
+
+    struct ValueRecord {
+      Value *Val;
+      unsigned Reg;
+      const Type *Ty;
+      ValueRecord(unsigned R, const Type *T) : Val(0), Reg(R), Ty(T) {}
+      ValueRecord(Value *V) : Val(V), Reg(0), Ty(V->getType()) {}
+    };
+    void doCall(const ValueRecord &Ret, MachineInstr *CallMI,
+                const std::vector<ValueRecord> &Args);
+    void visitCallInst(CallInst &I);
+    void visitIntrinsicCall(Intrinsic::ID ID, CallInst &I);
+
+    // Arithmetic operators
+    void visitSimpleBinary(BinaryOperator &B, unsigned OpcodeClass);
+    void visitAdd(BinaryOperator &B) { visitSimpleBinary(B, 0); }
+    void visitSub(BinaryOperator &B) { visitSimpleBinary(B, 1); }
+    void visitMul(BinaryOperator &B);
+
+    void visitDiv(BinaryOperator &B) { visitDivRem(B); }
+    void visitRem(BinaryOperator &B) { visitDivRem(B); }
+    void visitDivRem(BinaryOperator &B);
+
+    // Bitwise operators
+    void visitAnd(BinaryOperator &B) { visitSimpleBinary(B, 2); }
+    void visitOr (BinaryOperator &B) { visitSimpleBinary(B, 3); }
+    void visitXor(BinaryOperator &B) { visitSimpleBinary(B, 4); }
+
+    // Comparison operators...
+    void visitSetCondInst(SetCondInst &I);
+    unsigned EmitComparison(unsigned OpNum, Value *Op0, Value *Op1,
+                            MachineBasicBlock *MBB,
+                            MachineBasicBlock::iterator MBBI);
+    void visitSelectInst(SelectInst &SI);
+    
+    
+    // Memory Instructions
+    void visitLoadInst(LoadInst &I);
+    void visitStoreInst(StoreInst &I);
+    void visitGetElementPtrInst(GetElementPtrInst &I);
+    void visitAllocaInst(AllocaInst &I);
+    void visitMallocInst(MallocInst &I);
+    void visitFreeInst(FreeInst &I);
+    
+    // Other operators
+    void visitShiftInst(ShiftInst &I);
+    void visitPHINode(PHINode &I) {}      // PHI nodes handled by second pass
+    void visitCastInst(CastInst &I);
+    void visitVANextInst(VANextInst &I);
+    void visitVAArgInst(VAArgInst &I);
+
+    void visitInstruction(Instruction &I) {
+      std::cerr << "Cannot instruction select: " << I;
+      abort();
+    }
+
+    /// promote32 - Make a value 32-bits wide, and put it somewhere.
+    ///
+    void promote32(unsigned targetReg, const ValueRecord &VR);
+
+    /// emitGEPOperation - Common code shared between visitGetElementPtrInst and
+    /// constant expression GEP support.
+    ///
+    void emitGEPOperation(MachineBasicBlock *BB, MachineBasicBlock::iterator IP,
+                          Value *Src, User::op_iterator IdxBegin,
+                          User::op_iterator IdxEnd, unsigned TargetReg);
+
+    /// emitCastOperation - Common code shared between visitCastInst and
+    /// constant expression cast support.
+    ///
+    void emitCastOperation(MachineBasicBlock *BB,MachineBasicBlock::iterator IP,
+                           Value *Src, const Type *DestTy, unsigned TargetReg);
+
+    /// emitSimpleBinaryOperation - Common code shared between visitSimpleBinary
+    /// and constant expression support.
+    ///
+    void emitSimpleBinaryOperation(MachineBasicBlock *BB,
+                                   MachineBasicBlock::iterator IP,
+                                   Value *Op0, Value *Op1,
+                                   unsigned OperatorClass, unsigned TargetReg);
+
+    /// emitBinaryFPOperation - This method handles emission of floating point
+    /// Add (0), Sub (1), Mul (2), and Div (3) operations.
+    void emitBinaryFPOperation(MachineBasicBlock *BB,
+                               MachineBasicBlock::iterator IP,
+                               Value *Op0, Value *Op1,
+                               unsigned OperatorClass, unsigned TargetReg);
+
+    void emitMultiply(MachineBasicBlock *BB, MachineBasicBlock::iterator IP,
+                      Value *Op0, Value *Op1, unsigned TargetReg);
+
+    void doMultiply(MachineBasicBlock *MBB, MachineBasicBlock::iterator MBBI,
+                    unsigned DestReg, const Type *DestTy,
+                    unsigned Op0Reg, unsigned Op1Reg);
+    void doMultiplyConst(MachineBasicBlock *MBB, 
+                         MachineBasicBlock::iterator MBBI,
+                         unsigned DestReg, const Type *DestTy,
+                         unsigned Op0Reg, unsigned Op1Val);
+
+    void emitDivRemOperation(MachineBasicBlock *BB,
+                             MachineBasicBlock::iterator IP,
+                             Value *Op0, Value *Op1, bool isDiv,
+                             unsigned TargetReg);
+
+    /// emitSetCCOperation - Common code shared between visitSetCondInst and
+    /// constant expression support.
+    ///
+    void emitSetCCOperation(MachineBasicBlock *BB,
+                            MachineBasicBlock::iterator IP,
+                            Value *Op0, Value *Op1, unsigned Opcode,
+                            unsigned TargetReg);
+
+    /// emitShiftOperation - Common code shared between visitShiftInst and
+    /// constant expression support.
+    ///
+    void emitShiftOperation(MachineBasicBlock *MBB,
+                            MachineBasicBlock::iterator IP,
+                            Value *Op, Value *ShiftAmount, bool isLeftShift,
+                            const Type *ResultTy, unsigned DestReg);
+      
+    /// emitSelectOperation - Common code shared between visitSelectInst and the
+    /// constant expression support.
+    void emitSelectOperation(MachineBasicBlock *MBB,
+                             MachineBasicBlock::iterator IP,
+                             Value *Cond, Value *TrueVal, Value *FalseVal,
+                             unsigned DestReg);
+
+    /// copyConstantToRegister - Output the instructions required to put the
+    /// specified constant into the specified register.
+    ///
+    void copyConstantToRegister(MachineBasicBlock *MBB,
+                                MachineBasicBlock::iterator MBBI,
+                                Constant *C, unsigned Reg);
+
+    void emitUCOM(MachineBasicBlock *MBB, MachineBasicBlock::iterator MBBI,
+                   unsigned LHS, unsigned RHS);
+
+    /// makeAnotherReg - This method returns the next register number we haven't
+    /// yet used.
+    ///
+    /// Long values are handled somewhat specially.  They are always allocated
+    /// as pairs of 32 bit integer values.  The register number returned is the
+    /// lower 32 bits of the long value, and the regNum+1 is the upper 32 bits
+    /// of the long value.
+    ///
+    unsigned makeAnotherReg(const Type *Ty) {
+      assert(dynamic_cast<const PowerPCRegisterInfo*>(TM.getRegisterInfo()) &&
+             "Current target doesn't have PPC reg info??");
+      const PowerPCRegisterInfo *MRI =
+        static_cast<const PowerPCRegisterInfo*>(TM.getRegisterInfo());
+      if (Ty == Type::LongTy || Ty == Type::ULongTy) {
+        const TargetRegisterClass *RC = MRI->getRegClassForType(Type::IntTy);
+        // Create the lower part
+        F->getSSARegMap()->createVirtualRegister(RC);
+        // Create the upper part.
+        return F->getSSARegMap()->createVirtualRegister(RC)-1;
+      }
+
+      // Add the mapping of regnumber => reg class to MachineFunction
+      const TargetRegisterClass *RC = MRI->getRegClassForType(Ty);
+      return F->getSSARegMap()->createVirtualRegister(RC);
+    }
+
+    /// getReg - This method turns an LLVM value into a register number.
+    ///
+    unsigned getReg(Value &V) { return getReg(&V); }  // Allow references
+    unsigned getReg(Value *V) {
+      // Just append to the end of the current bb.
+      MachineBasicBlock::iterator It = BB->end();
+      return getReg(V, BB, It);
+    }
+    unsigned getReg(Value *V, MachineBasicBlock *MBB,
+                    MachineBasicBlock::iterator IPt);
+
+    /// getFixedSizedAllocaFI - Return the frame index for a fixed sized alloca
+    /// that is to be statically allocated with the initial stack frame
+    /// adjustment.
+    unsigned getFixedSizedAllocaFI(AllocaInst *AI);
+  };
+}
+
+/// dyn_castFixedAlloca - If the specified value is a fixed size alloca
+/// instruction in the entry block, return it.  Otherwise, return a null
+/// pointer.
+static AllocaInst *dyn_castFixedAlloca(Value *V) {
+  if (AllocaInst *AI = dyn_cast<AllocaInst>(V)) {
+    BasicBlock *BB = AI->getParent();
+    if (isa<ConstantUInt>(AI->getArraySize()) && BB ==&BB->getParent()->front())
+      return AI;
+  }
+  return 0;
+}
+
+/// getReg - This method turns an LLVM value into a register number.
+///
+unsigned ISel::getReg(Value *V, MachineBasicBlock *MBB,
+                      MachineBasicBlock::iterator IPt) {
+  // If this operand is a constant, emit the code to copy the constant into
+  // the register here...
+  //
+  if (Constant *C = dyn_cast<Constant>(V)) {
+    unsigned Reg = makeAnotherReg(V->getType());
+    copyConstantToRegister(MBB, IPt, C, Reg);
+    return Reg;
+  } else if (GlobalValue *GV = dyn_cast<GlobalValue>(V)) {
+    unsigned Reg1 = makeAnotherReg(V->getType());
+	unsigned Reg2 = makeAnotherReg(V->getType());
+    // Move the address of the global into the register
+    BuildMI(*MBB, IPt, PPC32::LOADHiAddr, 2, Reg1).addReg(PPC32::R0).addGlobalAddress(GV);
+    BuildMI(*MBB, IPt, PPC32::LOADLoAddr, 2, Reg2).addReg(Reg1).addGlobalAddress(GV);
+    return Reg2;
+  } else if (CastInst *CI = dyn_cast<CastInst>(V)) {
+    // Do not emit noop casts at all.
+    if (getClassB(CI->getType()) == getClassB(CI->getOperand(0)->getType()))
+      return getReg(CI->getOperand(0), MBB, IPt);
+  } else if (AllocaInst *AI = dyn_castFixedAlloca(V)) {
+    unsigned Reg = makeAnotherReg(V->getType());
+    unsigned FI = getFixedSizedAllocaFI(AI);
+    addFrameReference(BuildMI(*MBB, IPt, PPC32::ADDI, 2, Reg), FI, 0, false);
+    return Reg;
+  }
+
+  unsigned &Reg = RegMap[V];
+  if (Reg == 0) {
+    Reg = makeAnotherReg(V->getType());
+    RegMap[V] = Reg;
+  }
+
+  return Reg;
+}
+
+/// getFixedSizedAllocaFI - Return the frame index for a fixed sized alloca
+/// that is to be statically allocated with the initial stack frame
+/// adjustment.
+unsigned ISel::getFixedSizedAllocaFI(AllocaInst *AI) {
+  // Already computed this?
+  std::map<AllocaInst*, unsigned>::iterator I = AllocaMap.lower_bound(AI);
+  if (I != AllocaMap.end() && I->first == AI) return I->second;
+
+  const Type *Ty = AI->getAllocatedType();
+  ConstantUInt *CUI = cast<ConstantUInt>(AI->getArraySize());
+  unsigned TySize = TM.getTargetData().getTypeSize(Ty);
+  TySize *= CUI->getValue();   // Get total allocated size...
+  unsigned Alignment = TM.getTargetData().getTypeAlignment(Ty);
+      
+  // Create a new stack object using the frame manager...
+  int FrameIdx = F->getFrameInfo()->CreateStackObject(TySize, Alignment);
+  AllocaMap.insert(I, std::make_pair(AI, FrameIdx));
+  return FrameIdx;
+}
+
+
+/// copyConstantToRegister - Output the instructions required to put the
+/// specified constant into the specified register.
+///
+void ISel::copyConstantToRegister(MachineBasicBlock *MBB,
+                                  MachineBasicBlock::iterator IP,
+                                  Constant *C, unsigned R) {
+  if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
+    unsigned Class = 0;
+    switch (CE->getOpcode()) {
+    case Instruction::GetElementPtr:
+      emitGEPOperation(MBB, IP, CE->getOperand(0),
+                       CE->op_begin()+1, CE->op_end(), R);
+      return;
+    case Instruction::Cast:
+      emitCastOperation(MBB, IP, CE->getOperand(0), CE->getType(), R);
+      return;
+
+    case Instruction::Xor: ++Class; // FALL THROUGH
+    case Instruction::Or:  ++Class; // FALL THROUGH
+    case Instruction::And: ++Class; // FALL THROUGH
+    case Instruction::Sub: ++Class; // FALL THROUGH
+    case Instruction::Add:
+      emitSimpleBinaryOperation(MBB, IP, CE->getOperand(0), CE->getOperand(1),
+                                Class, R);
+      return;
+
+    case Instruction::Mul:
+      emitMultiply(MBB, IP, CE->getOperand(0), CE->getOperand(1), R);
+      return;
+
+    case Instruction::Div:
+    case Instruction::Rem:
+      emitDivRemOperation(MBB, IP, CE->getOperand(0), CE->getOperand(1),
+                          CE->getOpcode() == Instruction::Div, R);
+      return;
+
+    case Instruction::SetNE:
+    case Instruction::SetEQ:
+    case Instruction::SetLT:
+    case Instruction::SetGT:
+    case Instruction::SetLE:
+    case Instruction::SetGE:
+      emitSetCCOperation(MBB, IP, CE->getOperand(0), CE->getOperand(1),
+                         CE->getOpcode(), R);
+      return;
+
+    case Instruction::Shl:
+    case Instruction::Shr:
+      emitShiftOperation(MBB, IP, CE->getOperand(0), CE->getOperand(1),
+                         CE->getOpcode() == Instruction::Shl, CE->getType(), R);
+      return;
+
+    case Instruction::Select:
+      emitSelectOperation(MBB, IP, CE->getOperand(0), CE->getOperand(1),
+                          CE->getOperand(2), R);
+      return;
+
+    default:
+      std::cerr << "Offending expr: " << C << "\n";
+      assert(0 && "Constant expression not yet handled!\n");
+    }
+  }
+
+  if (C->getType()->isIntegral()) {
+    unsigned Class = getClassB(C->getType());
+
+    if (Class == cLong) {
+      // Copy the value into the register pair.
+      uint64_t Val = cast<ConstantInt>(C)->getRawValue();
+	  unsigned hiTmp = makeAnotherReg(Type::IntTy);
+	  unsigned loTmp = makeAnotherReg(Type::IntTy);
+      BuildMI(*MBB, IP, PPC32::ADDIS, 2, loTmp).addReg(PPC32::R0).addImm(Val >> 48);
+      BuildMI(*MBB, IP, PPC32::ORI, 2, R).addReg(loTmp).addImm((Val >> 32) & 0xFFFF);
+      BuildMI(*MBB, IP, PPC32::ADDIS, 2, hiTmp).addReg(PPC32::R0).addImm((Val >> 16) & 0xFFFF);
+      BuildMI(*MBB, IP, PPC32::ORI, 2, R+1).addReg(hiTmp).addImm(Val & 0xFFFF);
+      return;
+    }
+
+    assert(Class <= cInt && "Type not handled yet!");
+
+    if (C->getType() == Type::BoolTy) {
+      BuildMI(*MBB, IP, PPC32::ADDI, 2, R).addReg(PPC32::R0).addImm(C == ConstantBool::True);
+    } else if (Class == cByte || Class == cShort) {
+      ConstantInt *CI = cast<ConstantInt>(C);
+      BuildMI(*MBB, IP, PPC32::ADDI, 2, R).addReg(PPC32::R0).addImm(CI->getRawValue());
+    } else {
+      ConstantInt *CI = cast<ConstantInt>(C);
+      int TheVal = CI->getRawValue() & 0xFFFFFFFF;
+      if (TheVal < 32768 && TheVal >= -32768) {
+		BuildMI(*MBB, IP, PPC32::ADDI, 2, R).addReg(PPC32::R0).addImm(CI->getRawValue());
+	  } else {
+		unsigned TmpReg = makeAnotherReg(Type::IntTy);
+		BuildMI(*MBB, IP, PPC32::ADDIS, 2, TmpReg).addReg(PPC32::R0).addImm(CI->getRawValue() >> 16);
+		BuildMI(*MBB, IP, PPC32::ORI, 2, R).addReg(TmpReg).addImm(CI->getRawValue() & 0xFFFF);
+	  }
+    }
+  } else if (ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
+      // We need to spill the constant to memory...
+      MachineConstantPool *CP = F->getConstantPool();
+      unsigned CPI = CP->getConstantPoolIndex(CFP);
+      const Type *Ty = CFP->getType();
+
+      assert(Ty == Type::FloatTy || Ty == Type::DoubleTy && "Unknown FP type!"); 
+      unsigned LoadOpcode = Ty == Type::FloatTy ? PPC32::LFS : PPC32::LFD;
+      addConstantPoolReference(BuildMI(*MBB, IP, LoadOpcode, 2, R), CPI);
+  } else if (isa<ConstantPointerNull>(C)) {
+    // Copy zero (null pointer) to the register.
+    BuildMI(*MBB, IP, PPC32::ADDI, 2, R).addReg(PPC32::R0).addImm(0);
+  } else if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(C)) {
+    BuildMI(*MBB, IP, PPC32::ADDIS, 2, R).addReg(PPC32::R0).addGlobalAddress(CPR->getValue());
+    BuildMI(*MBB, IP, PPC32::ORI, 2, R).addReg(PPC32::R0).addGlobalAddress(CPR->getValue());
+  } else {
+    std::cerr << "Offending constant: " << C << "\n";
+    assert(0 && "Type not handled yet!");
+  }
+}
+
+/// LoadArgumentsToVirtualRegs - Load all of the arguments to this function from
+/// the stack into virtual registers.
+///
+/// FIXME: When we can calculate which args are coming in via registers
+/// source them from there instead.
+void ISel::LoadArgumentsToVirtualRegs(Function &Fn) {
+  unsigned ArgOffset = 0;   // Frame mechanisms handle retaddr slot
+  unsigned GPR_remaining = 8;
+  unsigned FPR_remaining = 13;
+  unsigned GPR_idx = 3;
+  unsigned FPR_idx = 1;
+	
+  MachineFrameInfo *MFI = F->getFrameInfo();
+
+  for (Function::aiterator I = Fn.abegin(), E = Fn.aend(); I != E; ++I) {
+    bool ArgLive = !I->use_empty();
+    unsigned Reg = ArgLive ? getReg(*I) : 0;
+    int FI;          // Frame object index
+
+    switch (getClassB(I->getType())) {
+    case cByte:
+      if (ArgLive) {
+        FI = MFI->CreateFixedObject(1, ArgOffset);
+		if (GPR_remaining > 0) {
+			BuildMI(BB, PPC32::OR, 2, Reg).addReg(PPC32::R0+GPR_idx).addReg(PPC32::R0+GPR_idx);
+		} else {
+			addFrameReference(BuildMI(BB, PPC32::LBZ, 2, Reg), FI);
+		}
+	  }
+      break;
+    case cShort:
+      if (ArgLive) {
+        FI = MFI->CreateFixedObject(2, ArgOffset);
+		if (GPR_remaining > 0) {
+			BuildMI(BB, PPC32::OR, 2, Reg).addReg(PPC32::R0+GPR_idx).addReg(PPC32::R0+GPR_idx);
+		} else {
+			addFrameReference(BuildMI(BB, PPC32::LHZ, 2, Reg), FI);
+		}
+	  }
+      break;
+    case cInt:
+      if (ArgLive) {
+        FI = MFI->CreateFixedObject(4, ArgOffset);
+		if (GPR_remaining > 0) {
+			BuildMI(BB, PPC32::OR, 2, Reg).addReg(PPC32::R0+GPR_idx).addReg(PPC32::R0+GPR_idx);
+		} else {
+			addFrameReference(BuildMI(BB, PPC32::LWZ, 2, Reg), FI);
+		}
+	  }
+      break;
+    case cLong:
+      if (ArgLive) {
+        FI = MFI->CreateFixedObject(8, ArgOffset);
+		if (GPR_remaining > 1) {
+			BuildMI(BB, PPC32::OR, 2, Reg).addReg(PPC32::R0+GPR_idx).addReg(PPC32::R0+GPR_idx);
+			BuildMI(BB, PPC32::OR, 2, Reg+1).addReg(PPC32::R0+GPR_idx+1).addReg(PPC32::R0+GPR_idx+1);
+		} else {
+			addFrameReference(BuildMI(BB, PPC32::LWZ, 2, Reg), FI);
+			addFrameReference(BuildMI(BB, PPC32::LWZ, 2, Reg+1), FI, 4);
+		}
+	  }
+      ArgOffset += 4;   // longs require 4 additional bytes
+	  if (GPR_remaining > 1) {
+		GPR_remaining--;    // uses up 2 GPRs
+		GPR_idx++;
+	  }
+      break;
+    case cFP:
+      if (ArgLive) {
+        unsigned Opcode;
+        if (I->getType() == Type::FloatTy) {
+          Opcode = PPC32::LFS;
+          FI = MFI->CreateFixedObject(4, ArgOffset);
+        } else {
+          Opcode = PPC32::LFD;
+          FI = MFI->CreateFixedObject(8, ArgOffset);
+        }
+		if (FPR_remaining > 0) {
+			BuildMI(BB, PPC32::FMR, 1, Reg).addReg(PPC32::F0+FPR_idx);
+			FPR_remaining--;
+			FPR_idx++;
+		} else {
+			addFrameReference(BuildMI(BB, Opcode, 2, Reg), FI);
+		}
+	  }
+      if (I->getType() == Type::DoubleTy) {
+        ArgOffset += 4;   // doubles require 4 additional bytes
+		if (GPR_remaining > 0) {
+			GPR_remaining--;    // uses up 2 GPRs
+			GPR_idx++;
+		}
+	  }
+      break;
+    default:
+      assert(0 && "Unhandled argument type!");
+    }
+    ArgOffset += 4;  // Each argument takes at least 4 bytes on the stack...
+	if (GPR_remaining > 0) {
+		GPR_remaining--;    // uses up 2 GPRs
+		GPR_idx++;
+	}
+  }
+
+  // If the function takes variable number of arguments, add a frame offset for
+  // the start of the first vararg value... this is used to expand
+  // llvm.va_start.
+  if (Fn.getFunctionType()->isVarArg())
+    VarArgsFrameIndex = MFI->CreateFixedObject(1, ArgOffset);
+}
+
+
+/// SelectPHINodes - Insert machine code to generate phis.  This is tricky
+/// because we have to generate our sources into the source basic blocks, not
+/// the current one.
+///
+void ISel::SelectPHINodes() {
+  const TargetInstrInfo &TII = *TM.getInstrInfo();
+  const Function &LF = *F->getFunction();  // The LLVM function...
+  for (Function::const_iterator I = LF.begin(), E = LF.end(); I != E; ++I) {
+    const BasicBlock *BB = I;
+    MachineBasicBlock &MBB = *MBBMap[I];
+
+    // Loop over all of the PHI nodes in the LLVM basic block...
+    MachineBasicBlock::iterator PHIInsertPoint = MBB.begin();
+    for (BasicBlock::const_iterator I = BB->begin();
+         PHINode *PN = const_cast<PHINode*>(dyn_cast<PHINode>(I)); ++I) {
+
+      // Create a new machine instr PHI node, and insert it.
+      unsigned PHIReg = getReg(*PN);
+      MachineInstr *PhiMI = BuildMI(MBB, PHIInsertPoint,
+                                    PPC32::PHI, PN->getNumOperands(), PHIReg);
+
+      MachineInstr *LongPhiMI = 0;
+      if (PN->getType() == Type::LongTy || PN->getType() == Type::ULongTy)
+        LongPhiMI = BuildMI(MBB, PHIInsertPoint,
+                            PPC32::PHI, PN->getNumOperands(), PHIReg+1);
+
+      // PHIValues - Map of blocks to incoming virtual registers.  We use this
+      // so that we only initialize one incoming value for a particular block,
+      // even if the block has multiple entries in the PHI node.
+      //
+      std::map<MachineBasicBlock*, unsigned> PHIValues;
+
+      for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) {
+        MachineBasicBlock *PredMBB = MBBMap[PN->getIncomingBlock(i)];
+        unsigned ValReg;
+        std::map<MachineBasicBlock*, unsigned>::iterator EntryIt =
+          PHIValues.lower_bound(PredMBB);
+
+        if (EntryIt != PHIValues.end() && EntryIt->first == PredMBB) {
+          // We already inserted an initialization of the register for this
+          // predecessor.  Recycle it.
+          ValReg = EntryIt->second;
+
+        } else {        
+          // Get the incoming value into a virtual register.
+          //
+          Value *Val = PN->getIncomingValue(i);
+
+          // If this is a constant or GlobalValue, we may have to insert code
+          // into the basic block to compute it into a virtual register.
+          if ((isa<Constant>(Val) && !isa<ConstantExpr>(Val)) ||
+              isa<GlobalValue>(Val)) {
+            // Simple constants get emitted at the end of the basic block,
+            // before any terminator instructions.  We "know" that the code to
+            // move a constant into a register will never clobber any flags.
+            ValReg = getReg(Val, PredMBB, PredMBB->getFirstTerminator());
+          } else {
+            // Because we don't want to clobber any values which might be in
+            // physical registers with the computation of this constant (which
+            // might be arbitrarily complex if it is a constant expression),
+            // just insert the computation at the top of the basic block.
+            MachineBasicBlock::iterator PI = PredMBB->begin();
+            
+            // Skip over any PHI nodes though!
+            while (PI != PredMBB->end() && PI->getOpcode() == PPC32::PHI)
+              ++PI;
+            
+            ValReg = getReg(Val, PredMBB, PI);
+          }
+
+          // Remember that we inserted a value for this PHI for this predecessor
+          PHIValues.insert(EntryIt, std::make_pair(PredMBB, ValReg));
+        }
+
+        PhiMI->addRegOperand(ValReg);
+        PhiMI->addMachineBasicBlockOperand(PredMBB);
+        if (LongPhiMI) {
+          LongPhiMI->addRegOperand(ValReg+1);
+          LongPhiMI->addMachineBasicBlockOperand(PredMBB);
+        }
+      }
+
+      // Now that we emitted all of the incoming values for the PHI node, make
+      // sure to reposition the InsertPoint after the PHI that we just added.
+      // This is needed because we might have inserted a constant into this
+      // block, right after the PHI's which is before the old insert point!
+      PHIInsertPoint = LongPhiMI ? LongPhiMI : PhiMI;
+      ++PHIInsertPoint;
+    }
+  }
+}
+
+
+// canFoldSetCCIntoBranchOrSelect - Return the setcc instruction if we can fold
+// it into the conditional branch or select instruction which is the only user
+// of the cc instruction.  This is the case if the conditional branch is the
+// only user of the setcc, and if the setcc is in the same basic block as the
+// conditional branch.  We also don't handle long arguments below, so we reject
+// them here as well.
+//
+static SetCondInst *canFoldSetCCIntoBranchOrSelect(Value *V) {
+  if (SetCondInst *SCI = dyn_cast<SetCondInst>(V))
+    if (SCI->hasOneUse()) {
+      Instruction *User = cast<Instruction>(SCI->use_back());
+      if ((isa<BranchInst>(User) || isa<SelectInst>(User)) &&
+          SCI->getParent() == User->getParent() &&
+          (getClassB(SCI->getOperand(0)->getType()) != cLong ||
+           SCI->getOpcode() == Instruction::SetEQ ||
+           SCI->getOpcode() == Instruction::SetNE))
+        return SCI;
+    }
+  return 0;
+}
+
+// Return a fixed numbering for setcc instructions which does not depend on the
+// order of the opcodes.
+//
+static unsigned getSetCCNumber(unsigned Opcode) {
+  switch(Opcode) {
+  default: assert(0 && "Unknown setcc instruction!");
+  case Instruction::SetEQ: return 0;
+  case Instruction::SetNE: return 1;
+  case Instruction::SetLT: return 2;
+  case Instruction::SetGE: return 3;
+  case Instruction::SetGT: return 4;
+  case Instruction::SetLE: return 5;
+  }
+}
+
+/// emitUCOM - emits an unordered FP compare.
+void ISel::emitUCOM(MachineBasicBlock *MBB, MachineBasicBlock::iterator IP,
+                     unsigned LHS, unsigned RHS) {
+	BuildMI(*MBB, IP, PPC32::FCMPU, 2, PPC32::CR0).addReg(LHS).addReg(RHS);
+}
+
+// EmitComparison - This function emits a comparison of the two operands,
+// returning the extended setcc code to use.
+unsigned ISel::EmitComparison(unsigned OpNum, Value *Op0, Value *Op1,
+                              MachineBasicBlock *MBB,
+                              MachineBasicBlock::iterator IP) {
+  // The arguments are already supposed to be of the same type.
+  const Type *CompTy = Op0->getType();
+  unsigned Class = getClassB(CompTy);
+  unsigned Op0r = getReg(Op0, MBB, IP);
+
+  // Special case handling of: cmp R, i
+  if (isa<ConstantPointerNull>(Op1)) {
+      BuildMI(*MBB, IP, PPC32::CMPI, 2, PPC32::CR0).addReg(Op0r).addImm(0);
+  } else if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
+    if (Class == cByte || Class == cShort || Class == cInt) {
+      unsigned Op1v = CI->getRawValue();
+
+      // Mask off any upper bits of the constant, if there are any...
+      Op1v &= (1ULL << (8 << Class)) - 1;
+
+	  // Compare immediate or promote to reg?
+	  if (Op1v <= 32767) {
+		BuildMI(*MBB, IP, CompTy->isSigned() ? PPC32::CMPI : PPC32::CMPLI, 3, PPC32::CR0).addImm(0).addReg(Op0r).addImm(Op1v);
+	  } else {
+		unsigned Op1r = getReg(Op1, MBB, IP);
+		BuildMI(*MBB, IP, CompTy->isSigned() ? PPC32::CMP : PPC32::CMPL, 3, PPC32::CR0).addImm(0).addReg(Op0r).addReg(Op1r);
+	  }
+      return OpNum;
+    } else {
+      assert(Class == cLong && "Unknown integer class!");
+      unsigned LowCst = CI->getRawValue();
+      unsigned HiCst = CI->getRawValue() >> 32;
+      if (OpNum < 2) {    // seteq, setne
+        unsigned LoTmp = Op0r;
+        if (LowCst != 0) {
+		  unsigned LoLow = makeAnotherReg(Type::IntTy);
+          unsigned LoTmp = makeAnotherReg(Type::IntTy);
+          BuildMI(*MBB, IP, PPC32::XORI, 2, LoLow).addReg(Op0r).addImm(LowCst);
+          BuildMI(*MBB, IP, PPC32::XORIS, 2, LoTmp).addReg(LoLow).addImm(LowCst >> 16);
+        }
+        unsigned HiTmp = Op0r+1;
+        if (HiCst != 0) {
+		  unsigned HiLow = makeAnotherReg(Type::IntTy);
+          unsigned HiTmp = makeAnotherReg(Type::IntTy);
+          BuildMI(*MBB, IP, PPC32::XORI, 2, HiLow).addReg(Op0r+1).addImm(HiCst);
+          BuildMI(*MBB, IP, PPC32::XORIS, 2, HiTmp).addReg(HiLow).addImm(HiCst >> 16);
+        }
+        unsigned FinalTmp = makeAnotherReg(Type::IntTy);
+        BuildMI(*MBB, IP, PPC32::ORo, 2, FinalTmp).addReg(LoTmp).addReg(HiTmp);
+        //BuildMI(*MBB, IP, PPC32::CMPLI, 2, PPC32::CR0).addReg(FinalTmp).addImm(0);
+        return OpNum;
+      } else {
+        // Emit a sequence of code which compares the high and low parts once
+        // each, then uses a conditional move to handle the overflow case.  For
+        // example, a setlt for long would generate code like this:
+        //
+        // AL = lo(op1) < lo(op2)   // Always unsigned comparison
+        // BL = hi(op1) < hi(op2)   // Signedness depends on operands
+        // dest = hi(op1) == hi(op2) ? BL : AL;
+        //
+
+        // FIXME: Not Yet Implemented
+		return OpNum;
+      }
+    }
+  }
+
+  unsigned Op1r = getReg(Op1, MBB, IP);
+  switch (Class) {
+  default: assert(0 && "Unknown type class!");
+  case cByte:
+  case cShort:
+  case cInt:
+	BuildMI(*MBB, IP, CompTy->isSigned() ? PPC32::CMP : PPC32::CMPL, 2, PPC32::CR0).addReg(Op0r).addReg(Op1r);
+    break;
+  case cFP:
+    emitUCOM(MBB, IP, Op0r, Op1r);
+    break;
+
+  case cLong:
+    if (OpNum < 2) {    // seteq, setne
+      unsigned LoTmp = makeAnotherReg(Type::IntTy);
+      unsigned HiTmp = makeAnotherReg(Type::IntTy);
+      unsigned FinalTmp = makeAnotherReg(Type::IntTy);
+      BuildMI(*MBB, IP, PPC32::XOR, 2, LoTmp).addReg(Op0r).addReg(Op1r);
+      BuildMI(*MBB, IP, PPC32::XOR, 2, HiTmp).addReg(Op0r+1).addReg(Op1r+1);
+      BuildMI(*MBB, IP, PPC32::ORo,  2, FinalTmp).addReg(LoTmp).addReg(HiTmp);
+      //BuildMI(*MBB, IP, PPC32::CMPLI, 2, PPC32::CR0).addReg(FinalTmp).addImm(0);
+      break;  // Allow the sete or setne to be generated from flags set by OR
+    } else {
+      // Emit a sequence of code which compares the high and low parts once
+      // each, then uses a conditional move to handle the overflow case.  For
+      // example, a setlt for long would generate code like this:
+      //
+      // AL = lo(op1) < lo(op2)   // Signedness depends on operands
+      // BL = hi(op1) < hi(op2)   // Always unsigned comparison
+      // dest = hi(op1) == hi(op2) ? BL : AL;
+      //
+
+      // FIXME: Not Yet Implemented
+      return OpNum;
+    }
+  }
+  return OpNum;
+}
+
+/// SetCC instructions - Here we just emit boilerplate code to set a byte-sized
+/// register, then move it to wherever the result should be. 
+///
+void ISel::visitSetCondInst(SetCondInst &I) {
+  if (canFoldSetCCIntoBranchOrSelect(&I))
+    return;  // Fold this into a branch or select.
+
+  unsigned DestReg = getReg(I);
+  MachineBasicBlock::iterator MII = BB->end();
+  emitSetCCOperation(BB, MII, I.getOperand(0), I.getOperand(1), I.getOpcode(),DestReg);
+}
+
+/// emitSetCCOperation - Common code shared between visitSetCondInst and
+/// constant expression support.
+///
+/// FIXME: this is wrong.  we should figure out a way to guarantee
+/// TargetReg is a CR and then make it a no-op
+void ISel::emitSetCCOperation(MachineBasicBlock *MBB,
+                              MachineBasicBlock::iterator IP,
+                              Value *Op0, Value *Op1, unsigned Opcode,
+                              unsigned TargetReg) {
+  unsigned OpNum = getSetCCNumber(Opcode);
+  OpNum = EmitComparison(OpNum, Op0, Op1, MBB, IP);
+
+  // The value is already in CR0 at this point, do nothing.
+}
+
+
+void ISel::visitSelectInst(SelectInst &SI) {
+  unsigned DestReg = getReg(SI);
+  MachineBasicBlock::iterator MII = BB->end();
+  emitSelectOperation(BB, MII, SI.getCondition(), SI.getTrueValue(),SI.getFalseValue(), DestReg);
+}
+ 
+/// emitSelect - Common code shared between visitSelectInst and the constant
+/// expression support.
+/// FIXME: this is most likely broken in one or more ways.  Namely, PowerPC has
+/// no select instruction.  FSEL only works for comparisons against zero.
+void ISel::emitSelectOperation(MachineBasicBlock *MBB,
+                               MachineBasicBlock::iterator IP,
+                               Value *Cond, Value *TrueVal, Value *FalseVal,
+                               unsigned DestReg) {
+  unsigned SelectClass = getClassB(TrueVal->getType());
+
+  unsigned TrueReg  = getReg(TrueVal, MBB, IP);
+  unsigned FalseReg = getReg(FalseVal, MBB, IP);
+
+  if (TrueReg == FalseReg) {
+	if (SelectClass == cFP) {
+		BuildMI(*MBB, IP, PPC32::FMR, 1, DestReg).addReg(TrueReg);
+	} else {
+		BuildMI(*MBB, IP, PPC32::OR, 2, DestReg).addReg(TrueReg).addReg(TrueReg);
+	}
+	
+    if (SelectClass == cLong)
+		BuildMI(*MBB, IP, PPC32::OR, 2, DestReg+1).addReg(TrueReg+1).addReg(TrueReg+1);
+    return;
+  }
+
+  unsigned CondReg = getReg(Cond, MBB, IP);
+  unsigned numZeros = makeAnotherReg(Type::IntTy);
+  unsigned falseHi = makeAnotherReg(Type::IntTy);
+  unsigned falseAll = makeAnotherReg(Type::IntTy);
+  unsigned trueAll = makeAnotherReg(Type::IntTy);
+  unsigned Temp1 = makeAnotherReg(Type::IntTy);
+  unsigned Temp2 = makeAnotherReg(Type::IntTy);
+
+  BuildMI(*MBB, IP, PPC32::CNTLZW, 1, numZeros).addReg(CondReg);
+  BuildMI(*MBB, IP, PPC32::RLWINM, 4, falseHi).addReg(numZeros).addImm(26).addImm(0).addImm(0);
+  BuildMI(*MBB, IP, PPC32::SRAWI, 2, falseAll).addReg(falseHi).addImm(31);
+  BuildMI(*MBB, IP, PPC32::NOR, 2, trueAll).addReg(falseAll).addReg(falseAll);
+  BuildMI(*MBB, IP, PPC32::AND, 2, Temp1).addReg(TrueReg).addReg(trueAll);
+  BuildMI(*MBB, IP, PPC32::AND, 2, Temp2).addReg(FalseReg).addReg(falseAll);
+  BuildMI(*MBB, IP, PPC32::OR, 2, DestReg).addReg(Temp1).addReg(Temp2);
+  
+  if (SelectClass == cLong) {
+	unsigned Temp3 = makeAnotherReg(Type::IntTy);
+	unsigned Temp4 = makeAnotherReg(Type::IntTy);
+	BuildMI(*MBB, IP, PPC32::AND, 2, Temp3).addReg(TrueReg+1).addReg(trueAll);
+	BuildMI(*MBB, IP, PPC32::AND, 2, Temp4).addReg(FalseReg+1).addReg(falseAll);
+	BuildMI(*MBB, IP, PPC32::OR, 2, DestReg+1).addReg(Temp3).addReg(Temp4);
+  }
+  
+  return;
+}
+
+
+
+/// promote32 - Emit instructions to turn a narrow operand into a 32-bit-wide
+/// operand, in the specified target register.
+///
+void ISel::promote32(unsigned targetReg, const ValueRecord &VR) {
+  bool isUnsigned = VR.Ty->isUnsigned() || VR.Ty == Type::BoolTy;
+
+  Value *Val = VR.Val;
+  const Type *Ty = VR.Ty;
+  if (Val) {
+    if (Constant *C = dyn_cast<Constant>(Val)) {
+      Val = ConstantExpr::getCast(C, Type::IntTy);
+      Ty = Type::IntTy;
+    }
+
+    // If this is a simple constant, just emit a load directly to avoid the copy.
+    if (ConstantInt *CI = dyn_cast<ConstantInt>(Val)) {
+      int TheVal = CI->getRawValue() & 0xFFFFFFFF;
+
+      if (TheVal < 32768 && TheVal >= -32768) {
+		BuildMI(BB, PPC32::ADDI, 2, targetReg).addReg(PPC32::R0).addImm(TheVal);
+	  } else {
+		unsigned TmpReg = makeAnotherReg(Type::IntTy);
+		BuildMI(BB, PPC32::ADDIS, 2, TmpReg).addReg(PPC32::R0).addImm(TheVal >> 16);
+		BuildMI(BB, PPC32::ORI, 2, targetReg).addReg(TmpReg).addImm(TheVal & 0xFFFF);
+	  }
+      return;
+    }
+  }
+
+  // Make sure we have the register number for this value...
+  unsigned Reg = Val ? getReg(Val) : VR.Reg;
+
+  switch (getClassB(Ty)) {
+  case cByte:
+    // Extend value into target register (8->32)
+    if (isUnsigned)
+      BuildMI(BB, PPC32::RLWINM, 4, targetReg).addReg(Reg).addZImm(0).addZImm(24).addZImm(31);
+    else
+      BuildMI(BB, PPC32::EXTSB, 1, targetReg).addReg(Reg);
+    break;
+  case cShort:
+    // Extend value into target register (16->32)
+    if (isUnsigned)
+      BuildMI(BB, PPC32::RLWINM, 4, targetReg).addReg(Reg).addZImm(0).addZImm(16).addZImm(31);
+    else
+      BuildMI(BB, PPC32::EXTSH, 1, targetReg).addReg(Reg);
+    break;
+  case cInt:
+    // Move value into target register (32->32)
+    BuildMI(BB, PPC32::ORI, 2, targetReg).addReg(Reg).addReg(Reg);
+    break;
+  default:
+    assert(0 && "Unpromotable operand class in promote32");
+  }
+}
+
+// just emit blr.
+void ISel::visitReturnInst(ReturnInst &I) {
+  Value *RetVal = I.getOperand(0);
+
+  switch (getClassB(RetVal->getType())) {
+  case cByte:   // integral return values: extend or move into r3 and return
+  case cShort:
+  case cInt:
+    promote32(PPC32::R3, ValueRecord(RetVal));
+    break;
+  case cFP: {   // Floats & Doubles: Return in f1
+    unsigned RetReg = getReg(RetVal);
+    BuildMI(BB, PPC32::FMR, 1, PPC32::F1).addReg(RetReg);
+    break;
+  }
+  case cLong: {
+    unsigned RetReg = getReg(RetVal);
+    BuildMI(BB, PPC32::OR, 2, PPC32::R3).addReg(RetReg).addReg(RetReg);
+    BuildMI(BB, PPC32::OR, 2, PPC32::R4).addReg(RetReg+1).addReg(RetReg+1);
+    break;
+  }
+  default:
+    visitInstruction(I);
+  }
+  BuildMI(BB, PPC32::BLR, 1).addImm(0);
+}
+
+// getBlockAfter - Return the basic block which occurs lexically after the
+// specified one.
+static inline BasicBlock *getBlockAfter(BasicBlock *BB) {
+  Function::iterator I = BB; ++I;  // Get iterator to next block
+  return I != BB->getParent()->end() ? &*I : 0;
+}
+
+/// visitBranchInst - Handle conditional and unconditional branches here.  Note
+/// that since code layout is frozen at this point, that if we are trying to
+/// jump to a block that is the immediate successor of the current block, we can
+/// just make a fall-through (but we don't currently).
+///
+void ISel::visitBranchInst(BranchInst &BI) {
+	// Update machine-CFG edges
+	BB->addSuccessor (MBBMap[BI.getSuccessor(0)]);
+	if (BI.isConditional())
+		BB->addSuccessor (MBBMap[BI.getSuccessor(1)]);
+	
+	BasicBlock *NextBB = getBlockAfter(BI.getParent());  // BB after current one
+	
+	if (!BI.isConditional()) {  // Unconditional branch?
+		if (BI.getSuccessor(0) != NextBB)
+			BuildMI(BB, PPC32::B, 1).addMBB(MBBMap[BI.getSuccessor(0)]);
+		return;
+	}
+	
+  // See if we can fold the setcc into the branch itself...
+  SetCondInst *SCI = canFoldSetCCIntoBranchOrSelect(BI.getCondition());
+  if (SCI == 0) {
+    // Nope, cannot fold setcc into this branch.  Emit a branch on a condition
+    // computed some other way...
+    unsigned condReg = getReg(BI.getCondition());
+	BuildMI(BB, PPC32::CMPLI, 3, PPC32::CR0).addImm(0).addReg(condReg).addImm(0);
+    if (BI.getSuccessor(1) == NextBB) {
+      if (BI.getSuccessor(0) != NextBB)
+        BuildMI(BB, PPC32::BC, 3).addImm(4).addImm(2).addMBB(MBBMap[BI.getSuccessor(0)]);
+    } else {
+	  BuildMI(BB, PPC32::BC, 3).addImm(12).addImm(2).addMBB(MBBMap[BI.getSuccessor(1)]);
+      
+      if (BI.getSuccessor(0) != NextBB)
+        BuildMI(BB, PPC32::B, 1).addMBB(MBBMap[BI.getSuccessor(0)]);
+    }
+    return;
+  }
+
+
+  unsigned OpNum = getSetCCNumber(SCI->getOpcode());
+  MachineBasicBlock::iterator MII = BB->end();
+  OpNum = EmitComparison(OpNum, SCI->getOperand(0), SCI->getOperand(1), BB,MII);
+
+  const Type *CompTy = SCI->getOperand(0)->getType();
+  bool isSigned = CompTy->isSigned() && getClassB(CompTy) != cFP;
+  
+  // LLVM  -> X86 signed  X86 unsigned
+  // -----    ----------  ------------
+  // seteq -> je          je
+  // setne -> jne         jne
+  // setlt -> jl          jb
+  // setge -> jge         jae
+  // setgt -> jg          ja
+  // setle -> jle         jbe
+
+  static const unsigned BITab[6] = { 2, 2, 0, 0, 1, 1 };
+  unsigned BO_true = (OpNum % 2 == 0) ? 12 : 4;
+  unsigned BO_false = (OpNum % 2 == 0) ? 4 : 12;
+  unsigned BIval = BITab[0];
+
+  if (BI.getSuccessor(0) != NextBB) {
+		BuildMI(BB, PPC32::BC, 3).addImm(BO_true).addImm(BIval).addMBB(MBBMap[BI.getSuccessor(0)]);
+    if (BI.getSuccessor(1) != NextBB)
+		BuildMI(BB, PPC32::B, 1).addMBB(MBBMap[BI.getSuccessor(1)]);
+  } else {
+    // Change to the inverse condition...
+    if (BI.getSuccessor(1) != NextBB) {
+	  BuildMI(BB, PPC32::BC, 3).addImm(BO_false).addImm(BIval).addMBB(MBBMap[BI.getSuccessor(1)]);
+    }
+  }
+}
+
+
+/// doCall - This emits an abstract call instruction, setting up the arguments
+/// and the return value as appropriate.  For the actual function call itself,
+/// it inserts the specified CallMI instruction into the stream.
+///
+/// FIXME: See Documentation at the following URL for "correct" behavior
+/// <http://developer.apple.com/documentation/DeveloperTools/Conceptual/MachORuntime/2rt_powerpc_abi/chapter_9_section_5.html>
+void ISel::doCall(const ValueRecord &Ret, MachineInstr *CallMI,
+                  const std::vector<ValueRecord> &Args) {
+  // Count how many bytes are to be pushed on the stack...
+  unsigned NumBytes = 0;
+
+  if (!Args.empty()) {
+    for (unsigned i = 0, e = Args.size(); i != e; ++i)
+      switch (getClassB(Args[i].Ty)) {
+      case cByte: case cShort: case cInt:
+        NumBytes += 4; break;
+      case cLong:
+        NumBytes += 8; break;
+      case cFP:
+        NumBytes += Args[i].Ty == Type::FloatTy ? 4 : 8;
+        break;
+      default: assert(0 && "Unknown class!");
+      }
+
+    // Adjust the stack pointer for the new arguments...
+    BuildMI(BB, PPC32::ADJCALLSTACKDOWN, 1).addImm(NumBytes);
+
+    // Arguments go on the stack in reverse order, as specified by the ABI.
+    unsigned ArgOffset = 0;
+	unsigned GPR_remaining = 8;
+	unsigned FPR_remaining = 13;
+	unsigned GPR_idx = 3;
+	unsigned FPR_idx = 1;
+	
+    for (unsigned i = 0, e = Args.size(); i != e; ++i) {
+      unsigned ArgReg;
+      switch (getClassB(Args[i].Ty)) {
+      case cByte:
+      case cShort:
+        // Promote arg to 32 bits wide into a temporary register...
+        ArgReg = makeAnotherReg(Type::UIntTy);
+        promote32(ArgReg, Args[i]);
+		  
+		// Reg or stack?
+		if (GPR_remaining > 0) {
+			BuildMI(BB, PPC32::OR, 2, PPC32::R0 + GPR_idx).addReg(ArgReg).addReg(ArgReg);
+		} else {
+			BuildMI(BB, PPC32::STW, 3).addReg(ArgReg).addImm(ArgOffset).addReg(PPC32::R1);
+		}
+		break;
+      case cInt:
+        ArgReg = Args[i].Val ? getReg(Args[i].Val) : Args[i].Reg;
+
+		// Reg or stack?
+		if (GPR_remaining > 0) {
+		    BuildMI(BB, PPC32::OR, 2, PPC32::R0 + GPR_idx).addReg(ArgReg).addReg(ArgReg);
+		} else {
+		    BuildMI(BB, PPC32::STW, 3).addReg(ArgReg).addImm(ArgOffset).addReg(PPC32::R1);
+		}
+		break;
+      case cLong:
+		ArgReg = Args[i].Val ? getReg(Args[i].Val) : Args[i].Reg;
+
+		// Reg or stack?
+		if (GPR_remaining > 1) {
+		    BuildMI(BB, PPC32::OR, 2, PPC32::R0 + GPR_idx).addReg(ArgReg).addReg(ArgReg);
+		    BuildMI(BB, PPC32::OR, 2, PPC32::R0 + GPR_idx + 1).addReg(ArgReg+1).addReg(ArgReg+1);
+		} else {
+		    BuildMI(BB, PPC32::STW, 3).addReg(ArgReg).addImm(ArgOffset).addReg(PPC32::R1);
+		    BuildMI(BB, PPC32::STW, 3).addReg(ArgReg+1).addImm(ArgOffset+4).addReg(PPC32::R1);
+		}
+
+        ArgOffset += 4;        // 8 byte entry, not 4.
+		if (GPR_remaining > 0) {
+			GPR_remaining -= 1;    // uses up 2 GPRs
+			GPR_idx += 1;
+		}
+        break;
+      case cFP:
+        ArgReg = Args[i].Val ? getReg(Args[i].Val) : Args[i].Reg;
+        if (Args[i].Ty == Type::FloatTy) {
+			// Reg or stack?
+			if (FPR_remaining > 0) {
+				BuildMI(BB, PPC32::FMR, 1, PPC32::F0 + FPR_idx).addReg(ArgReg);
+				FPR_remaining--;
+				FPR_idx++;
+			} else {
+				BuildMI(BB, PPC32::STFS, 3).addReg(ArgReg).addImm(ArgOffset).addReg(PPC32::R1);
+			}
+        } else {
+          assert(Args[i].Ty == Type::DoubleTy && "Unknown FP type!");
+			// Reg or stack?
+			if (FPR_remaining > 0) {
+				BuildMI(BB, PPC32::FMR, 1, PPC32::F0 + FPR_idx).addReg(ArgReg);
+				FPR_remaining--;
+				FPR_idx++;
+			} else {
+				BuildMI(BB, PPC32::STFD, 3).addReg(ArgReg).addImm(ArgOffset).addReg(PPC32::R1);
+			}
+
+			ArgOffset += 4;       // 8 byte entry, not 4.
+			if (GPR_remaining > 0) {
+				GPR_remaining--;    // uses up 2 GPRs
+				GPR_idx++;
+			}
+        }
+        break;
+
+      default: assert(0 && "Unknown class!");
+      }
+      ArgOffset += 4;
+	  if (GPR_remaining > 0) {
+		GPR_remaining--;    // uses up 2 GPRs
+		GPR_idx++;
+	  }
+    }
+  } else {
+    BuildMI(BB, PPC32::ADJCALLSTACKDOWN, 1).addImm(0);
+  }
+
+  BB->push_back(CallMI);
+
+  BuildMI(BB, PPC32::ADJCALLSTACKUP, 1).addImm(NumBytes);
+
+  // If there is a return value, scavenge the result from the location the call
+  // leaves it in...
+  //
+  if (Ret.Ty != Type::VoidTy) {
+    unsigned DestClass = getClassB(Ret.Ty);
+    switch (DestClass) {
+    case cByte:
+    case cShort:
+    case cInt:
+      // Integral results are in r3
+	  BuildMI(BB, PPC32::OR, 2, Ret.Reg).addReg(PPC32::R3).addReg(PPC32::R3);
+    case cFP:     // Floating-point return values live in f1
+      BuildMI(BB, PPC32::FMR, 1, Ret.Reg).addReg(PPC32::F1);
+      break;
+    case cLong:   // Long values are in r3:r4
+	  BuildMI(BB, PPC32::OR, 2, Ret.Reg).addReg(PPC32::R3).addReg(PPC32::R3);
+	  BuildMI(BB, PPC32::OR, 2, Ret.Reg+1).addReg(PPC32::R4).addReg(PPC32::R4);
+      break;
+    default: assert(0 && "Unknown class!");
+    }
+  }
+}
+
+
+/// visitCallInst - Push args on stack and do a procedure call instruction.
+void ISel::visitCallInst(CallInst &CI) {
+  MachineInstr *TheCall;
+  if (Function *F = CI.getCalledFunction()) {
+    // Is it an intrinsic function call?
+    if (Intrinsic::ID ID = (Intrinsic::ID)F->getIntrinsicID()) {
+      visitIntrinsicCall(ID, CI);   // Special intrinsics are not handled here
+      return;
+    }
+
+    // Emit a CALL instruction with PC-relative displacement.
+    TheCall = BuildMI(PPC32::CALLpcrel, 1).addGlobalAddress(F, true);
+  } else {  // Emit an indirect call through the CTR
+    unsigned Reg = getReg(CI.getCalledValue());
+    BuildMI(PPC32::MTSPR, 2).addZImm(9).addReg(Reg);
+    TheCall = BuildMI(PPC32::CALLindirect, 1).addZImm(20).addZImm(0);
+  }
+
+  std::vector<ValueRecord> Args;
+  for (unsigned i = 1, e = CI.getNumOperands(); i != e; ++i)
+    Args.push_back(ValueRecord(CI.getOperand(i)));
+
+  unsigned DestReg = CI.getType() != Type::VoidTy ? getReg(CI) : 0;
+  doCall(ValueRecord(DestReg, CI.getType()), TheCall, Args);
+}         
+
+
+/// dyncastIsNan - Return the operand of an isnan operation if this is an isnan.
+///
+static Value *dyncastIsNan(Value *V) {
+  if (CallInst *CI = dyn_cast<CallInst>(V))
+    if (Function *F = CI->getCalledFunction())
+      if (F->getIntrinsicID() == Intrinsic::isnan)
+        return CI->getOperand(1);
+  return 0;
+}
+
+/// isOnlyUsedByUnorderedComparisons - Return true if this value is only used by
+/// or's whos operands are all calls to the isnan predicate.
+static bool isOnlyUsedByUnorderedComparisons(Value *V) {
+  assert(dyncastIsNan(V) && "The value isn't an isnan call!");
+
+  // Check all uses, which will be or's of isnans if this predicate is true.
+  for (Value::use_iterator UI = V->use_begin(), E = V->use_end(); UI != E;++UI){
+    Instruction *I = cast<Instruction>(*UI);
+    if (I->getOpcode() != Instruction::Or) return false;
+    if (I->getOperand(0) != V && !dyncastIsNan(I->getOperand(0))) return false;
+    if (I->getOperand(1) != V && !dyncastIsNan(I->getOperand(1))) return false;
+  }
+
+  return true;
+}
+
+/// LowerUnknownIntrinsicFunctionCalls - This performs a prepass over the
+/// function, lowering any calls to unknown intrinsic functions into the
+/// equivalent LLVM code.
+///
+void ISel::LowerUnknownIntrinsicFunctionCalls(Function &F) {
+  for (Function::iterator BB = F.begin(), E = F.end(); BB != E; ++BB)
+    for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; )
+      if (CallInst *CI = dyn_cast<CallInst>(I++))
+        if (Function *F = CI->getCalledFunction())
+          switch (F->getIntrinsicID()) {
+          case Intrinsic::not_intrinsic:
+          case Intrinsic::vastart:
+          case Intrinsic::vacopy:
+          case Intrinsic::vaend:
+          case Intrinsic::returnaddress:
+          case Intrinsic::frameaddress:
+          case Intrinsic::isnan:
+            // We directly implement these intrinsics
+            break;
+          case Intrinsic::readio: {
+            // On PPC, memory operations are in-order.  Lower this intrinsic
+            // into a volatile load.
+            Instruction *Before = CI->getPrev();
+            LoadInst * LI = new LoadInst(CI->getOperand(1), "", true, CI);
+            CI->replaceAllUsesWith(LI);
+            BB->getInstList().erase(CI);
+            break;
+          }
+          case Intrinsic::writeio: {
+            // On PPC, memory operations are in-order.  Lower this intrinsic
+            // into a volatile store.
+            Instruction *Before = CI->getPrev();
+            StoreInst *LI = new StoreInst(CI->getOperand(1),
+                                          CI->getOperand(2), true, CI);
+            CI->replaceAllUsesWith(LI);
+            BB->getInstList().erase(CI);
+            break;
+          }
+          default:
+            // All other intrinsic calls we must lower.
+            Instruction *Before = CI->getPrev();
+            TM.getIntrinsicLowering().LowerIntrinsicCall(CI);
+            if (Before) {        // Move iterator to instruction after call
+              I = Before; ++I;
+            } else {
+              I = BB->begin();
+            }
+          }
+}
+
+void ISel::visitIntrinsicCall(Intrinsic::ID ID, CallInst &CI) {
+  unsigned TmpReg1, TmpReg2, TmpReg3;
+  switch (ID) {
+  case Intrinsic::vastart:
+    // Get the address of the first vararg value...
+    TmpReg1 = getReg(CI);
+    addFrameReference(BuildMI(BB, PPC32::ADDI, 2, TmpReg1), VarArgsFrameIndex);
+    return;
+
+  case Intrinsic::vacopy:
+    TmpReg1 = getReg(CI);
+    TmpReg2 = getReg(CI.getOperand(1));
+    BuildMI(BB, PPC32::OR, 2, TmpReg1).addReg(TmpReg2).addReg(TmpReg2);
+    return;
+  case Intrinsic::vaend: return;
+
+  case Intrinsic::returnaddress:
+  case Intrinsic::frameaddress:
+    TmpReg1 = getReg(CI);
+    if (cast<Constant>(CI.getOperand(1))->isNullValue()) {
+      if (ID == Intrinsic::returnaddress) {
+        // Just load the return address
+        addFrameReference(BuildMI(BB, PPC32::LWZ, 2, TmpReg1),
+                          ReturnAddressIndex);
+      } else {
+        addFrameReference(BuildMI(BB, PPC32::ADDI, 2, TmpReg1),
+                          ReturnAddressIndex, -4, false);
+      }
+    } else {
+      // Values other than zero are not implemented yet.
+      BuildMI(BB, PPC32::ADDI, 2, TmpReg1).addReg(PPC32::R0).addImm(0);
+    }
+    return;
+
+  case Intrinsic::isnan:
+    // If this is only used by 'isunordered' style comparisons, don't emit it.
+    if (isOnlyUsedByUnorderedComparisons(&CI)) return;
+    TmpReg1 = getReg(CI.getOperand(1));
+    emitUCOM(BB, BB->end(), TmpReg1, TmpReg1);
+	TmpReg2 = makeAnotherReg(Type::IntTy);
+	BuildMI(BB, PPC32::MFCR, TmpReg2);
+    TmpReg3 = getReg(CI);
+    BuildMI(BB, PPC32::RLWINM, 4, TmpReg3).addReg(TmpReg2).addImm(4).addImm(31).addImm(31);
+    return;
+
+  default: assert(0 && "Error: unknown intrinsics should have been lowered!");
+  }
+}
+
+/// visitSimpleBinary - Implement simple binary operators for integral types...
+/// OperatorClass is one of: 0 for Add, 1 for Sub, 2 for And, 3 for Or, 4 for
+/// Xor.
+///
+void ISel::visitSimpleBinary(BinaryOperator &B, unsigned OperatorClass) {
+  unsigned DestReg = getReg(B);
+  MachineBasicBlock::iterator MI = BB->end();
+  Value *Op0 = B.getOperand(0), *Op1 = B.getOperand(1);
+  unsigned Class = getClassB(B.getType());
+
+  emitSimpleBinaryOperation(BB, MI, Op0, Op1, OperatorClass, DestReg);
+}
+
+/// emitBinaryFPOperation - This method handles emission of floating point
+/// Add (0), Sub (1), Mul (2), and Div (3) operations.
+void ISel::emitBinaryFPOperation(MachineBasicBlock *BB,
+                                 MachineBasicBlock::iterator IP,
+                                 Value *Op0, Value *Op1,
+                                 unsigned OperatorClass, unsigned DestReg) {
+
+  // Special case: op Reg, <const fp>
+  if (ConstantFP *Op1C = dyn_cast<ConstantFP>(Op1)) {
+      // Create a constant pool entry for this constant.
+      MachineConstantPool *CP = F->getConstantPool();
+      unsigned CPI = CP->getConstantPoolIndex(Op1C);
+      const Type *Ty = Op1->getType();
+
+      static const unsigned OpcodeTab[][4] = {
+        { PPC32::FADDS, PPC32::FSUBS, PPC32::FMULS, PPC32::FDIVS },   // Float
+        { PPC32::FADD, PPC32::FSUB, PPC32::FMUL, PPC32::FDIV },   // Double
+      };
+
+      assert(Ty == Type::FloatTy || Ty == Type::DoubleTy && "Unknown FP type!");
+	  unsigned TempReg = makeAnotherReg(Ty);
+      unsigned LoadOpcode = Ty == Type::FloatTy ? PPC32::LFS : PPC32::LFD;
+      addConstantPoolReference(BuildMI(*BB, IP, LoadOpcode, 2, TempReg), CPI);
+
+      unsigned Opcode = OpcodeTab[Ty != Type::FloatTy][OperatorClass];
+      unsigned Op0r = getReg(Op0, BB, IP);
+	  BuildMI(*BB, IP, Opcode, DestReg).addReg(Op0r).addReg(TempReg);
+      return;
+    }
+  
+  // Special case: R1 = op <const fp>, R2
+  if (ConstantFP *CFP = dyn_cast<ConstantFP>(Op0))
+    if (CFP->isExactlyValue(-0.0) && OperatorClass == 1) {
+      // -0.0 - X === -X
+      unsigned op1Reg = getReg(Op1, BB, IP);
+      BuildMI(*BB, IP, PPC32::FNEG, 1, DestReg).addReg(op1Reg);
+      return;
+    } else {
+      // R1 = op CST, R2  -->  R1 = opr R2, CST
+
+      // Create a constant pool entry for this constant.
+      MachineConstantPool *CP = F->getConstantPool();
+      unsigned CPI = CP->getConstantPoolIndex(CFP);
+      const Type *Ty = CFP->getType();
+
+      static const unsigned OpcodeTab[][4] = {
+        { PPC32::FADDS, PPC32::FSUBS, PPC32::FMULS, PPC32::FDIVS },   // Float
+        { PPC32::FADD, PPC32::FSUB, PPC32::FMUL, PPC32::FDIV },   // Double
+      };
+
+      assert(Ty == Type::FloatTy || Ty == Type::DoubleTy && "Unknown FP type!");
+	  unsigned TempReg = makeAnotherReg(Ty);
+      unsigned LoadOpcode = Ty == Type::FloatTy ? PPC32::LFS : PPC32::LFD;
+      addConstantPoolReference(BuildMI(*BB, IP, LoadOpcode, 2, TempReg), CPI);
+
+      unsigned Opcode = OpcodeTab[Ty != Type::FloatTy][OperatorClass];
+      unsigned Op1r = getReg(Op1, BB, IP);
+	  BuildMI(*BB, IP, Opcode, DestReg).addReg(TempReg).addReg(Op1r);
+      return;
+    }
+
+  // General case.
+  static const unsigned OpcodeTab[4] = {
+    PPC32::FADD, PPC32::FSUB, PPC32::FMUL, PPC32::FDIV
+  };
+
+  unsigned Opcode = OpcodeTab[OperatorClass];
+  unsigned Op0r = getReg(Op0, BB, IP);
+  unsigned Op1r = getReg(Op1, BB, IP);
+  BuildMI(*BB, IP, Opcode, 2, DestReg).addReg(Op0r).addReg(Op1r);
+}
+
+/// emitSimpleBinaryOperation - Implement simple binary operators for integral
+/// types...  OperatorClass is one of: 0 for Add, 1 for Sub, 2 for And, 3 for
+/// Or, 4 for Xor.
+///
+/// emitSimpleBinaryOperation - Common code shared between visitSimpleBinary
+/// and constant expression support.
+///
+void ISel::emitSimpleBinaryOperation(MachineBasicBlock *MBB,
+                                     MachineBasicBlock::iterator IP,
+                                     Value *Op0, Value *Op1,
+                                     unsigned OperatorClass, unsigned DestReg) {
+  unsigned Class = getClassB(Op0->getType());
+
+    // Arithmetic and Bitwise operators
+    static const unsigned OpcodeTab[5] = {
+	  PPC32::ADD, PPC32::SUB, PPC32::AND, PPC32::OR, PPC32::XOR
+	};
+    // Otherwise, code generate the full operation with a constant.
+    static const unsigned BottomTab[] = {
+      PPC32::ADDC, PPC32::SUBC, PPC32::AND, PPC32::OR, PPC32::XOR
+    };
+    static const unsigned TopTab[] = {
+      PPC32::ADDE, PPC32::SUBFE, PPC32::AND, PPC32::OR, PPC32::XOR
+    };
+  
+  if (Class == cFP) {
+    assert(OperatorClass < 2 && "No logical ops for FP!");
+    emitBinaryFPOperation(MBB, IP, Op0, Op1, OperatorClass, DestReg);
+    return;
+  }
+
+  if (Op0->getType() == Type::BoolTy) {
+    if (OperatorClass == 3)
+      // If this is an or of two isnan's, emit an FP comparison directly instead
+      // of or'ing two isnan's together.
+      if (Value *LHS = dyncastIsNan(Op0))
+        if (Value *RHS = dyncastIsNan(Op1)) {
+          unsigned Op0Reg = getReg(RHS, MBB, IP), Op1Reg = getReg(LHS, MBB, IP);
+		  unsigned TmpReg = makeAnotherReg(Type::IntTy);
+          emitUCOM(MBB, IP, Op0Reg, Op1Reg);
+		  BuildMI(*MBB, IP, PPC32::MFCR, TmpReg);
+		  BuildMI(*MBB, IP, PPC32::RLWINM, 4, DestReg).addReg(TmpReg).addImm(4).addImm(31).addImm(31);
+          return;
+        }
+  }
+
+  // sub 0, X -> neg X
+  if (ConstantInt *CI = dyn_cast<ConstantInt>(Op0))
+    if (OperatorClass == 1 && CI->isNullValue()) {
+      unsigned op1Reg = getReg(Op1, MBB, IP);
+      BuildMI(*MBB, IP, PPC32::NEG, 1, DestReg).addReg(op1Reg);
+      
+      if (Class == cLong) {
+		unsigned zeroes = makeAnotherReg(Type::IntTy);
+		unsigned overflow = makeAnotherReg(Type::IntTy);
+        unsigned T = makeAnotherReg(Type::IntTy);
+		BuildMI(*MBB, IP, PPC32::CNTLZW, 1, zeroes).addReg(op1Reg);
+		BuildMI(*MBB, IP, PPC32::RLWINM, 4, overflow).addReg(zeroes).addImm(27).addImm(5).addImm(31);
+		BuildMI(*MBB, IP, PPC32::ADD, 2, T).addReg(op1Reg+1).addReg(overflow);
+		BuildMI(*MBB, IP, PPC32::NEG, 1, DestReg+1).addReg(T);
+      }
+      return;
+    }
+
+  // Special case: op Reg, <const int>
+  if (ConstantInt *Op1C = dyn_cast<ConstantInt>(Op1)) {
+    unsigned Op0r = getReg(Op0, MBB, IP);
+
+    // xor X, -1 -> not X
+    if (OperatorClass == 4 && Op1C->isAllOnesValue()) {
+      BuildMI(*MBB, IP, PPC32::NOR, 2, DestReg).addReg(Op0r).addReg(Op0r);
+      if (Class == cLong)  // Invert the top part too
+        BuildMI(*MBB, IP, PPC32::NOR, 2, DestReg+1).addReg(Op0r+1).addReg(Op0r+1);
+      return;
+    }
+
+    unsigned Opcode = OpcodeTab[OperatorClass];
+    unsigned Op1r = getReg(Op1, MBB, IP);
+
+    if (Class != cLong) {
+      BuildMI(*MBB, IP, Opcode, 2, DestReg).addReg(Op0r).addReg(Op1r);
+      return;
+    }
+    
+    // If the constant is zero in the low 32-bits, just copy the low part
+    // across and apply the normal 32-bit operation to the high parts.  There
+    // will be no carry or borrow into the top.
+    if (cast<ConstantInt>(Op1C)->getRawValue() == 0) {
+      if (OperatorClass != 2) // All but and...
+        BuildMI(*MBB, IP, PPC32::OR, 2, DestReg).addReg(Op0r).addReg(Op0r);
+      else
+        BuildMI(*MBB, IP, PPC32::ADDI, 2, DestReg).addReg(PPC32::R0).addImm(0);
+	  BuildMI(*MBB, IP, Opcode, 2, DestReg+1).addReg(Op0r+1).addReg(Op1r+1);
+      return;
+    }
+    
+    // If this is a long value and the high or low bits have a special
+    // property, emit some special cases.
+    unsigned Op1h = cast<ConstantInt>(Op1C)->getRawValue() >> 32LL;
+    
+    // If this is a logical operation and the top 32-bits are zero, just
+    // operate on the lower 32.
+    if (Op1h == 0 && OperatorClass > 1) {
+      BuildMI(*MBB, IP, Opcode, 2, DestReg).addReg(Op0r).addReg(Op1r);
+      if (OperatorClass != 2)  // All but and
+        BuildMI(*MBB, IP, PPC32::OR, 2, DestReg+1).addReg(Op0r+1).addReg(Op0r+1);
+      else
+        BuildMI(*MBB, IP, PPC32::ADDI, 2, DestReg+1).addReg(PPC32::R0).addImm(0);
+      return;
+    }
+    
+    // TODO: We could handle lots of other special cases here, such as AND'ing
+    // with 0xFFFFFFFF00000000 -> noop, etc.
+    
+    BuildMI(*MBB, IP, BottomTab[OperatorClass], 2, DestReg).addReg(Op0r).addImm(Op1r);
+    BuildMI(*MBB, IP, TopTab[OperatorClass], 2, DestReg+1).addReg(Op0r+1).addImm(Op1r+1);
+    return;
+  }
+
+  unsigned Op0r = getReg(Op0, MBB, IP);
+  unsigned Op1r = getReg(Op1, MBB, IP);
+
+  if (Class != cLong) {
+	unsigned Opcode = OpcodeTab[OperatorClass];
+	BuildMI(*MBB, IP, Opcode, 2, DestReg).addReg(Op0r).addReg(Op1r);
+  } else {
+    BuildMI(*MBB, IP, BottomTab[OperatorClass], 2, DestReg).addReg(Op0r).addImm(Op1r);
+    BuildMI(*MBB, IP, TopTab[OperatorClass], 2, DestReg+1).addReg(Op0r+1).addImm(Op1r+1);
+  }
+  return;
+}
+
+/// doMultiply - Emit appropriate instructions to multiply together the
+/// registers op0Reg and op1Reg, and put the result in DestReg.  The type of the
+/// result should be given as DestTy.
+///
+void ISel::doMultiply(MachineBasicBlock *MBB, MachineBasicBlock::iterator MBBI,
+                      unsigned DestReg, const Type *DestTy,
+                      unsigned op0Reg, unsigned op1Reg) {
+  unsigned Class = getClass(DestTy);
+  switch (Class) {
+  case cLong:
+    BuildMI(*MBB, MBBI, PPC32::MULHW, 2, DestReg+1).addReg(op0Reg+1).addReg(op1Reg+1);
+  case cInt:
+  case cShort:
+  case cByte:
+    BuildMI(*MBB, MBBI, PPC32::MULLW, 2, DestReg).addReg(op0Reg).addReg(op1Reg);
+    return;
+  default:
+	assert(0 && "doMultiply cannot operate on unknown type!");
+  }
+}
+
+// ExactLog2 - This function solves for (Val == 1 << (N-1)) and returns N.  It
+// returns zero when the input is not exactly a power of two.
+static unsigned ExactLog2(unsigned Val) {
+  if (Val == 0 || (Val & (Val-1))) return 0;
+  unsigned Count = 0;
+  while (Val != 1) {
+    Val >>= 1;
+    ++Count;
+  }
+  return Count+1;
+}
+
+
+/// doMultiplyConst - This function is specialized to efficiently codegen an 8,
+/// 16, or 32-bit integer multiply by a constant.
+void ISel::doMultiplyConst(MachineBasicBlock *MBB,
+                           MachineBasicBlock::iterator IP,
+                           unsigned DestReg, const Type *DestTy,
+                           unsigned op0Reg, unsigned ConstRHS) {
+  unsigned Class = getClass(DestTy);
+  // Handle special cases here.
+  switch (ConstRHS) {
+  case 0:
+    BuildMI(*MBB, IP, PPC32::ADDI, 2, DestReg).addReg(PPC32::R0).addImm(0);
+    return;
+  case 1:
+    BuildMI(*MBB, IP, PPC32::OR, 2, DestReg).addReg(op0Reg).addReg(op0Reg);
+    return;
+  case 2:
+    BuildMI(*MBB, IP, PPC32::ADD, 2,DestReg).addReg(op0Reg).addReg(op0Reg);
+    return;
+  }
+
+  // If the element size is exactly a power of 2, use a shift to get it.
+  if (unsigned Shift = ExactLog2(ConstRHS)) {
+    switch (Class) {
+    default: assert(0 && "Unknown class for this function!");
+    case cByte:
+    case cShort:
+    case cInt:
+      BuildMI(*MBB, IP, PPC32::RLWINM, 4, DestReg).addReg(op0Reg).addImm(Shift-1).addImm(0).addImm(31-Shift-1);
+      return;
+    }
+  }
+  
+  // Most general case, emit a normal multiply...
+  unsigned TmpReg1 = makeAnotherReg(Type::IntTy);
+  unsigned TmpReg2 = makeAnotherReg(Type::IntTy);
+  BuildMI(*MBB, IP, PPC32::ADDIS, 2, TmpReg1).addReg(PPC32::R0).addImm(ConstRHS >> 16);
+  BuildMI(*MBB, IP, PPC32::ORI, 2, TmpReg2).addReg(TmpReg1).addImm(ConstRHS);
+  
+  // Emit a MUL to multiply the register holding the index by
+  // elementSize, putting the result in OffsetReg.
+  doMultiply(MBB, IP, DestReg, DestTy, op0Reg, TmpReg2);
+}
+
+void ISel::visitMul(BinaryOperator &I) {
+  unsigned ResultReg = getReg(I);
+
+  Value *Op0 = I.getOperand(0);
+  Value *Op1 = I.getOperand(1);
+
+  MachineBasicBlock::iterator IP = BB->end();
+  emitMultiply(BB, IP, Op0, Op1, ResultReg);
+}
+
+void ISel::emitMultiply(MachineBasicBlock *MBB, MachineBasicBlock::iterator IP,
+                        Value *Op0, Value *Op1, unsigned DestReg) {
+  MachineBasicBlock &BB = *MBB;
+  TypeClass Class = getClass(Op0->getType());
+
+  // Simple scalar multiply?
+  unsigned Op0Reg  = getReg(Op0, &BB, IP);
+  switch (Class) {
+  case cByte:
+  case cShort:
+  case cInt:
+    if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
+      unsigned Val = (unsigned)CI->getRawValue(); // Isn't a 64-bit constant
+      doMultiplyConst(&BB, IP, DestReg, Op0->getType(), Op0Reg, Val);
+    } else {
+      unsigned Op1Reg  = getReg(Op1, &BB, IP);
+      doMultiply(&BB, IP, DestReg, Op1->getType(), Op0Reg, Op1Reg);
+    }
+    return;
+  case cFP:
+    emitBinaryFPOperation(MBB, IP, Op0, Op1, 2, DestReg);
+    return;
+  case cLong:
+    break;
+  }
+
+  // Long value.  We have to do things the hard way...
+  if (ConstantInt *CI = dyn_cast<ConstantInt>(Op1)) {
+    unsigned CLow = CI->getRawValue();
+    unsigned CHi  = CI->getRawValue() >> 32;
+    
+    if (CLow == 0) {
+      // If the low part of the constant is all zeros, things are simple.
+      BuildMI(BB, IP, PPC32::ADDI, 2, DestReg).addReg(PPC32::R0).addImm(0);
+      doMultiplyConst(&BB, IP, DestReg+1, Type::UIntTy, Op0Reg, CHi);
+      return;
+    }
+    
+    // Multiply the two low parts
+    unsigned OverflowReg = 0;
+    if (CLow == 1) {
+      BuildMI(BB, IP, PPC32::OR, 2, DestReg).addReg(Op0Reg).addReg(Op0Reg);
+    } else {
+	  unsigned TmpRegL = makeAnotherReg(Type::UIntTy);
+      unsigned Op1RegL = makeAnotherReg(Type::UIntTy);
+      OverflowReg = makeAnotherReg(Type::UIntTy);
+	  BuildMI(BB, IP, PPC32::ADDIS, 2, TmpRegL).addReg(PPC32::R0).addImm(CLow >> 16);
+	  BuildMI(BB, IP, PPC32::ORI, 2, Op1RegL).addReg(TmpRegL).addImm(CLow);
+	  BuildMI(BB, IP, PPC32::MULLW, 2, DestReg).addReg(Op0Reg).addReg(Op1RegL);
+	  BuildMI(BB, IP, PPC32::MULHW, 2, OverflowReg).addReg(Op0Reg).addReg(Op1RegL);
+    }
+    
+    unsigned AHBLReg = makeAnotherReg(Type::UIntTy);
+    doMultiplyConst(&BB, IP, AHBLReg, Type::UIntTy, Op0Reg+1, CLow);
+    
+    unsigned AHBLplusOverflowReg;
+    if (OverflowReg) {
+      AHBLplusOverflowReg = makeAnotherReg(Type::UIntTy);
+      BuildMI(BB, IP, PPC32::ADD, 2,                // AH*BL+(AL*BL >> 32)
+              AHBLplusOverflowReg).addReg(AHBLReg).addReg(OverflowReg);
+    } else {
+      AHBLplusOverflowReg = AHBLReg;
+    }
+    
+    if (CHi == 0) {
+      BuildMI(BB, IP, PPC32::OR, 2, DestReg+1).addReg(AHBLplusOverflowReg).addReg(AHBLplusOverflowReg);
+    } else {
+      unsigned ALBHReg = makeAnotherReg(Type::UIntTy); // AL*BH
+      doMultiplyConst(&BB, IP, ALBHReg, Type::UIntTy, Op0Reg, CHi);
+      
+      BuildMI(BB, IP, PPC32::ADD, 2,      // AL*BH + AH*BL + (AL*BL >> 32)
+              DestReg+1).addReg(AHBLplusOverflowReg).addReg(ALBHReg);
+    }
+    return;
+  }
+
+  // General 64x64 multiply
+
+  unsigned Op1Reg  = getReg(Op1, &BB, IP);
+  
+  // Multiply the two low parts... capturing carry into EDX
+  BuildMI(BB, IP, PPC32::MULLW, 2, DestReg).addReg(Op0Reg).addReg(Op1Reg);  // AL*BL
+  
+  unsigned OverflowReg = makeAnotherReg(Type::UIntTy);
+  BuildMI(BB, IP, PPC32::MULHW, 2, OverflowReg).addReg(Op0Reg).addReg(Op1Reg); // AL*BL >> 32
+  
+  unsigned AHBLReg = makeAnotherReg(Type::UIntTy);   // AH*BL
+  BuildMI(BB, IP, PPC32::MULLW, 2, AHBLReg).addReg(Op0Reg+1).addReg(Op1Reg);
+  
+  unsigned AHBLplusOverflowReg = makeAnotherReg(Type::UIntTy);
+  BuildMI(BB, IP, PPC32::ADD, 2,                // AH*BL+(AL*BL >> 32)
+          AHBLplusOverflowReg).addReg(AHBLReg).addReg(OverflowReg);
+  
+  unsigned ALBHReg = makeAnotherReg(Type::UIntTy); // AL*BH
+  BuildMI(BB, IP, PPC32::MULLW, 2, ALBHReg).addReg(Op0Reg).addReg(Op1Reg+1);
+  
+  BuildMI(BB, IP, PPC32::ADD, 2,      // AL*BH + AH*BL + (AL*BL >> 32)
+          DestReg+1).addReg(AHBLplusOverflowReg).addReg(ALBHReg);
+}
+
+
+/// visitDivRem - Handle division and remainder instructions... these
+/// instruction both require the same instructions to be generated, they just
+/// select the result from a different register.  Note that both of these
+/// instructions work differently for signed and unsigned operands.
+///
+void ISel::visitDivRem(BinaryOperator &I) {
+  unsigned ResultReg = getReg(I);
+  Value *Op0 = I.getOperand(0), *Op1 = I.getOperand(1);
+
+  MachineBasicBlock::iterator IP = BB->end();
+  emitDivRemOperation(BB, IP, Op0, Op1, I.getOpcode() == Instruction::Div, ResultReg);
+}
+
+void ISel::emitDivRemOperation(MachineBasicBlock *BB,
+                               MachineBasicBlock::iterator IP,
+                               Value *Op0, Value *Op1, bool isDiv,
+                               unsigned ResultReg) {
+  const Type *Ty = Op0->getType();
+  unsigned Class = getClass(Ty);
+  switch (Class) {
+  case cFP:              // Floating point divide
+    if (isDiv) {
+      emitBinaryFPOperation(BB, IP, Op0, Op1, 3, ResultReg);
+      return;
+    } else {               // Floating point remainder...
+      unsigned Op0Reg = getReg(Op0, BB, IP);
+      unsigned Op1Reg = getReg(Op1, BB, IP);
+      MachineInstr *TheCall =
+        BuildMI(PPC32::CALLpcrel, 1).addExternalSymbol("fmod", true);
+      std::vector<ValueRecord> Args;
+      Args.push_back(ValueRecord(Op0Reg, Type::DoubleTy));
+      Args.push_back(ValueRecord(Op1Reg, Type::DoubleTy));
+      doCall(ValueRecord(ResultReg, Type::DoubleTy), TheCall, Args);
+    }
+    return;
+  case cLong: {
+    static const char *FnName[] =
+      { "__moddi3", "__divdi3", "__umoddi3", "__udivdi3" };
+    unsigned Op0Reg = getReg(Op0, BB, IP);
+    unsigned Op1Reg = getReg(Op1, BB, IP);
+    unsigned NameIdx = Ty->isUnsigned()*2 + isDiv;
+    MachineInstr *TheCall =
+      BuildMI(PPC32::CALLpcrel, 1).addExternalSymbol(FnName[NameIdx], true);
+
+    std::vector<ValueRecord> Args;
+    Args.push_back(ValueRecord(Op0Reg, Type::LongTy));
+    Args.push_back(ValueRecord(Op1Reg, Type::LongTy));
+    doCall(ValueRecord(ResultReg, Type::LongTy), TheCall, Args);
+    return;
+  }
+  case cByte: case cShort: case cInt:
+    break;          // Small integrals, handled below...
+  default: assert(0 && "Unknown class!");
+  }
+
+  // Special case signed division by power of 2.
+  if (isDiv)
+    if (ConstantSInt *CI = dyn_cast<ConstantSInt>(Op1)) {
+      assert(Class != cLong && "This doesn't handle 64-bit divides!");
+      int V = CI->getValue();
+
+      if (V == 1) {       // X /s 1 => X
+        unsigned Op0Reg = getReg(Op0, BB, IP);
+        BuildMI(*BB, IP, PPC32::OR, 2, ResultReg).addReg(Op0Reg).addReg(Op0Reg);
+        return;
+      }
+
+      if (V == -1) {      // X /s -1 => -X
+        unsigned Op0Reg = getReg(Op0, BB, IP);
+        BuildMI(*BB, IP, PPC32::NEG, 1, ResultReg).addReg(Op0Reg);
+        return;
+      }
+
+      bool isNeg = false;
+      if (V < 0) {         // Not a positive power of 2?
+        V = -V;
+        isNeg = true;      // Maybe it's a negative power of 2.
+      }
+      if (unsigned Log = ExactLog2(V)) {
+        --Log;
+        unsigned Op0Reg = getReg(Op0, BB, IP);
+        unsigned TmpReg = makeAnotherReg(Op0->getType());
+        if (Log != 1) 
+          BuildMI(*BB, IP, PPC32::SRAWI, 2, TmpReg).addReg(Op0Reg).addImm(Log-1);
+        else
+          BuildMI(*BB, IP, PPC32::OR, 2, TmpReg).addReg(Op0Reg).addReg(Op0Reg);
+
+        unsigned TmpReg2 = makeAnotherReg(Op0->getType());
+        BuildMI(*BB, IP, PPC32::RLWINM, 4, TmpReg2).addReg(TmpReg).addImm(Log).addImm(32-Log).addImm(31);
+
+        unsigned TmpReg3 = makeAnotherReg(Op0->getType());
+        BuildMI(*BB, IP, PPC32::ADD, 2, TmpReg3).addReg(Op0Reg).addReg(TmpReg2);
+
+        unsigned TmpReg4 = isNeg ? makeAnotherReg(Op0->getType()) : ResultReg;
+        BuildMI(*BB, IP, PPC32::SRAWI, 2, TmpReg4).addReg(Op0Reg).addImm(Log);
+
+        if (isNeg)
+          BuildMI(*BB, IP, PPC32::NEG, 1, ResultReg).addReg(TmpReg4);
+        return;
+      }
+    }
+
+  unsigned Op0Reg = getReg(Op0, BB, IP);
+  unsigned Op1Reg = getReg(Op1, BB, IP);
+
+  if (isDiv) {
+	if (Ty->isSigned()) {
+		BuildMI(*BB, IP, PPC32::DIVW, 2, ResultReg).addReg(Op0Reg).addReg(Op1Reg);
+	} else {
+		BuildMI(*BB, IP, PPC32::DIVWU, 2, ResultReg).addReg(Op0Reg).addReg(Op1Reg);
+	}
+  } else { // Remainder
+	unsigned TmpReg1 = makeAnotherReg(Op0->getType());
+	unsigned TmpReg2 = makeAnotherReg(Op0->getType());
+	
+	if (Ty->isSigned()) {
+		BuildMI(*BB, IP, PPC32::DIVW, 2, TmpReg1).addReg(Op0Reg).addReg(Op1Reg);
+	} else {
+		BuildMI(*BB, IP, PPC32::DIVWU, 2, TmpReg1).addReg(Op0Reg).addReg(Op1Reg);
+	}
+	BuildMI(*BB, IP, PPC32::MULLW, 2, TmpReg2).addReg(TmpReg1).addReg(Op1Reg);
+	BuildMI(*BB, IP, PPC32::SUBF, 2, ResultReg).addReg(TmpReg2).addReg(Op0Reg);
+  }
+}
+
+
+/// Shift instructions: 'shl', 'sar', 'shr' - Some special cases here
+/// for constant immediate shift values, and for constant immediate
+/// shift values equal to 1. Even the general case is sort of special,
+/// because the shift amount has to be in CL, not just any old register.
+///
+void ISel::visitShiftInst(ShiftInst &I) {
+  MachineBasicBlock::iterator IP = BB->end ();
+  emitShiftOperation (BB, IP, I.getOperand (0), I.getOperand (1),
+                      I.getOpcode () == Instruction::Shl, I.getType (),
+                      getReg (I));
+}
+
+/// emitShiftOperation - Common code shared between visitShiftInst and
+/// constant expression support.
+void ISel::emitShiftOperation(MachineBasicBlock *MBB,
+                              MachineBasicBlock::iterator IP,
+                              Value *Op, Value *ShiftAmount, bool isLeftShift,
+                              const Type *ResultTy, unsigned DestReg) {
+  unsigned SrcReg = getReg (Op, MBB, IP);
+  bool isSigned = ResultTy->isSigned ();
+  unsigned Class = getClass (ResultTy);
+  
+  // Longs, as usual, are handled specially...
+  if (Class == cLong) {
+    // If we have a constant shift, we can generate much more efficient code
+    // than otherwise...
+    //
+    if (ConstantUInt *CUI = dyn_cast<ConstantUInt>(ShiftAmount)) {
+      unsigned Amount = CUI->getValue();
+      if (Amount < 32) {
+        if (isLeftShift) {
+		  // FIXME: RLWIMI is a use-and-def of DestReg+1, but that violates SSA
+          BuildMI(*MBB, IP, PPC32::RLWINM, 4, DestReg+1).addReg(SrcReg+1).addImm(Amount).addImm(0).addImm(31-Amount);
+          BuildMI(*MBB, IP, PPC32::RLWIMI, 5).addReg(DestReg+1).addReg(SrcReg).addImm(Amount).addImm(32-Amount).addImm(31);
+          BuildMI(*MBB, IP, PPC32::RLWINM, 4, DestReg).addReg(SrcReg).addImm(Amount).addImm(0).addImm(31-Amount);
+        } else {
+		  // FIXME: RLWIMI is a use-and-def of DestReg, but that violates SSA
+          BuildMI(*MBB, IP, PPC32::RLWINM, 4, DestReg).addReg(SrcReg).addImm(32-Amount).addImm(Amount).addImm(31);
+          BuildMI(*MBB, IP, PPC32::RLWIMI, 5).addReg(DestReg).addReg(SrcReg+1).addImm(32-Amount).addImm(0).addImm(Amount-1);
+          BuildMI(*MBB, IP, PPC32::RLWINM, 4, DestReg+1).addReg(SrcReg+1).addImm(32-Amount).addImm(Amount).addImm(31);
+        }
+      } else {                 // Shifting more than 32 bits
+        Amount -= 32;
+        if (isLeftShift) {
+          if (Amount != 0) {
+			BuildMI(*MBB, IP, PPC32::RLWINM, 4, DestReg+1).addReg(SrcReg).addImm(Amount).addImm(0).addImm(31-Amount);
+          } else {
+            BuildMI(*MBB, IP, PPC32::OR, 2, DestReg+1).addReg(SrcReg).addReg(SrcReg);
+          }
+          BuildMI(*MBB, IP, PPC32::ADDI, 2, DestReg).addReg(PPC32::R0).addImm(0);
+        } else {
+          if (Amount != 0) {
+			if (isSigned)
+				BuildMI(*MBB, IP, PPC32::SRAWI, 2, DestReg).addReg(SrcReg+1).addImm(Amount);
+			else
+				BuildMI(*MBB, IP, PPC32::RLWINM, 4, DestReg).addReg(SrcReg+1).addImm(32-Amount).addImm(Amount).addImm(31);
+          } else {
+            BuildMI(*MBB, IP, PPC32::OR, 2, DestReg).addReg(SrcReg+1).addReg(SrcReg+1);
+          }
+          BuildMI(*MBB, IP, PPC32::ADDI, 2, DestReg+1).addReg(PPC32::R0).addImm(0);
+        }
+      }
+    } else {
+      unsigned TmpReg1 = makeAnotherReg(Type::IntTy);
+      unsigned TmpReg2 = makeAnotherReg(Type::IntTy);
+	  unsigned TmpReg3 = makeAnotherReg(Type::IntTy);
+	  unsigned TmpReg4 = makeAnotherReg(Type::IntTy);
+	  unsigned TmpReg5 = makeAnotherReg(Type::IntTy);
+	  unsigned TmpReg6 = makeAnotherReg(Type::IntTy);
+	  unsigned ShiftAmountReg = getReg (ShiftAmount, MBB, IP);
+	  
+      if (isLeftShift) {
+		BuildMI(*MBB, IP, PPC32::SUBFIC, 2, TmpReg1).addReg(ShiftAmountReg).addImm(32);
+		BuildMI(*MBB, IP, PPC32::SLW, 2, TmpReg2).addReg(SrcReg+1).addReg(ShiftAmountReg);
+		BuildMI(*MBB, IP, PPC32::SRW, 2, TmpReg3).addReg(SrcReg).addReg(TmpReg1);
+		BuildMI(*MBB, IP, PPC32::OR, 2, TmpReg4).addReg(TmpReg2).addReg(TmpReg3);
+		BuildMI(*MBB, IP, PPC32::ADDI, 2, TmpReg5).addReg(ShiftAmountReg).addImm(-32);
+		BuildMI(*MBB, IP, PPC32::SLW, 2, TmpReg6).addReg(SrcReg).addReg(TmpReg5);
+		BuildMI(*MBB, IP, PPC32::OR, 2, DestReg+1).addReg(TmpReg4).addReg(TmpReg6);
+		BuildMI(*MBB, IP, PPC32::SLW, 2, DestReg).addReg(SrcReg).addReg(ShiftAmountReg);
+	  } else {
+		if (isSigned) {
+			// FIXME: Unimplmented
+			// Page C-3 of the PowerPC 32bit Programming Environments Manual
+		} else {
+			BuildMI(*MBB, IP, PPC32::SUBFIC, 2, TmpReg1).addReg(ShiftAmountReg).addImm(32);
+			BuildMI(*MBB, IP, PPC32::SRW, 2, TmpReg2).addReg(SrcReg).addReg(ShiftAmountReg);
+			BuildMI(*MBB, IP, PPC32::SLW, 2, TmpReg3).addReg(SrcReg+1).addReg(TmpReg1);
+			BuildMI(*MBB, IP, PPC32::OR, 2, TmpReg4).addReg(TmpReg2).addReg(TmpReg3);
+			BuildMI(*MBB, IP, PPC32::ADDI, 2, TmpReg5).addReg(ShiftAmountReg).addImm(-32);
+			BuildMI(*MBB, IP, PPC32::SRW, 2, TmpReg6).addReg(SrcReg+1).addReg(TmpReg5);
+			BuildMI(*MBB, IP, PPC32::OR, 2, DestReg).addReg(TmpReg4).addReg(TmpReg6);
+			BuildMI(*MBB, IP, PPC32::SRW, 2, DestReg+1).addReg(SrcReg+1).addReg(ShiftAmountReg);
+		}
+	  }
+    }
+    return;
+  }
+
+  if (ConstantUInt *CUI = dyn_cast<ConstantUInt>(ShiftAmount)) {
+    // The shift amount is constant, guaranteed to be a ubyte. Get its value.
+    assert(CUI->getType() == Type::UByteTy && "Shift amount not a ubyte?");
+    unsigned Amount = CUI->getValue();
+
+	if (isLeftShift) {
+		BuildMI(*MBB, IP, PPC32::RLWINM, 4, DestReg).addReg(SrcReg).addImm(Amount).addImm(0).addImm(31-Amount);
+	} else {
+		if (isSigned) {
+			BuildMI(*MBB, IP, PPC32::SRAWI, 2, DestReg).addReg(SrcReg).addImm(Amount);
+		} else {
+			BuildMI(*MBB, IP, PPC32::RLWINM, 4, DestReg).addReg(SrcReg).addImm(32-Amount).addImm(Amount).addImm(31);
+		}
+	}
+  } else {                  // The shift amount is non-constant.
+    unsigned ShiftAmountReg = getReg (ShiftAmount, MBB, IP);
+
+	if (isLeftShift) {
+		BuildMI(*MBB, IP, PPC32::SLW, 2, DestReg).addReg(SrcReg).addReg(ShiftAmountReg);
+	} else {
+		BuildMI(*MBB, IP, isSigned ? PPC32::SRAW : PPC32::SRW, 2, DestReg).addReg(SrcReg).addReg(ShiftAmountReg);
+	}
+  }
+}
+
+
+/// visitLoadInst - Implement LLVM load instructions
+///
+void ISel::visitLoadInst(LoadInst &I) {
+  static const unsigned Opcodes[] = { PPC32::LBZ, PPC32::LHZ, PPC32::LWZ, PPC32::LFS };
+  unsigned Class = getClassB(I.getType());
+  unsigned Opcode = Opcodes[Class];
+  if (I.getType() == Type::DoubleTy) Opcode = PPC32::LFD;
+
+  unsigned DestReg = getReg(I);
+
+  if (AllocaInst *AI = dyn_castFixedAlloca(I.getOperand(0))) {
+	unsigned FI = getFixedSizedAllocaFI(AI);
+    if (Class == cLong) {
+		addFrameReference(BuildMI(BB, PPC32::LWZ, 2, DestReg), FI);
+		addFrameReference(BuildMI(BB, PPC32::LWZ, 2, DestReg+1), FI, 4);
+    } else {
+		addFrameReference(BuildMI(BB, Opcode, 2, DestReg), FI);
+	}
+  } else {
+	unsigned SrcAddrReg = getReg(I.getOperand(0));
+    
+    if (Class == cLong) {
+      BuildMI(BB, PPC32::LWZ, 2, DestReg).addImm(0).addReg(SrcAddrReg);
+      BuildMI(BB, PPC32::LWZ, 2, DestReg+1).addImm(4).addReg(SrcAddrReg);
+    } else {
+      BuildMI(BB, Opcode, 2, DestReg).addImm(0).addReg(SrcAddrReg);
+    }
+  }
+}
+
+/// visitStoreInst - Implement LLVM store instructions
+///
+void ISel::visitStoreInst(StoreInst &I) {
+  unsigned ValReg      = getReg(I.getOperand(0));
+  unsigned AddressReg  = getReg(I.getOperand(1));
+ 
+  const Type *ValTy = I.getOperand(0)->getType();
+  unsigned Class = getClassB(ValTy);
+
+  if (Class == cLong) {
+	BuildMI(BB, PPC32::STW, 3).addReg(ValReg).addImm(0).addReg(AddressReg);
+   	BuildMI(BB, PPC32::STW, 3).addReg(ValReg+1).addImm(4).addReg(AddressReg);
+    return;
+  }
+
+  static const unsigned Opcodes[] = {
+    PPC32::STB, PPC32::STH, PPC32::STW, PPC32::STFS
+  };
+  unsigned Opcode = Opcodes[Class];
+  if (ValTy == Type::DoubleTy) Opcode = PPC32::STFD;
+  BuildMI(BB, Opcode, 3).addReg(ValReg).addImm(0).addReg(AddressReg);
+}
+
+
+/// visitCastInst - Here we have various kinds of copying with or without sign
+/// extension going on.
+///
+void ISel::visitCastInst(CastInst &CI) {
+  Value *Op = CI.getOperand(0);
+
+  unsigned SrcClass = getClassB(Op->getType());
+  unsigned DestClass = getClassB(CI.getType());
+  // Noop casts are not emitted: getReg will return the source operand as the
+  // register to use for any uses of the noop cast.
+  if (DestClass == SrcClass)
+    return;
+
+  // If this is a cast from a 32-bit integer to a Long type, and the only uses
+  // of the case are GEP instructions, then the cast does not need to be
+  // generated explicitly, it will be folded into the GEP.
+  if (DestClass == cLong && SrcClass == cInt) {
+    bool AllUsesAreGEPs = true;
+    for (Value::use_iterator I = CI.use_begin(), E = CI.use_end(); I != E; ++I)
+      if (!isa<GetElementPtrInst>(*I)) {
+        AllUsesAreGEPs = false;
+        break;
+      }        
+
+    // No need to codegen this cast if all users are getelementptr instrs...
+    if (AllUsesAreGEPs) return;
+  }
+
+  unsigned DestReg = getReg(CI);
+  MachineBasicBlock::iterator MI = BB->end();
+  emitCastOperation(BB, MI, Op, CI.getType(), DestReg);
+}
+
+/// emitCastOperation - Common code shared between visitCastInst and constant
+/// expression cast support.
+///
+void ISel::emitCastOperation(MachineBasicBlock *BB,
+                             MachineBasicBlock::iterator IP,
+                             Value *Src, const Type *DestTy,
+                             unsigned DestReg) {
+  const Type *SrcTy = Src->getType();
+  unsigned SrcClass = getClassB(SrcTy);
+  unsigned DestClass = getClassB(DestTy);
+  unsigned SrcReg = getReg(Src, BB, IP);
+
+  // Implement casts to bool by using compare on the operand followed by set if
+  // not zero on the result.
+  if (DestTy == Type::BoolTy) {
+    switch (SrcClass) {
+    case cByte:
+	case cShort:
+    case cInt: {
+      unsigned TmpReg = makeAnotherReg(Type::IntTy);
+	  BuildMI(*BB, IP, PPC32::ADDIC, 2, TmpReg).addReg(SrcReg).addImm(-1);
+	  BuildMI(*BB, IP, PPC32::SUBFE, 2, DestReg).addReg(TmpReg).addReg(SrcReg);
+      break;
+    }
+    case cLong: {
+      unsigned TmpReg = makeAnotherReg(Type::IntTy);
+      unsigned SrcReg2 = makeAnotherReg(Type::IntTy);
+      BuildMI(*BB, IP, PPC32::OR, 2, SrcReg2).addReg(SrcReg).addReg(SrcReg+1);
+	  BuildMI(*BB, IP, PPC32::ADDIC, 2, TmpReg).addReg(SrcReg2).addImm(-1);
+	  BuildMI(*BB, IP, PPC32::SUBFE, 2, DestReg).addReg(TmpReg).addReg(SrcReg2);
+      break;
+    }
+    case cFP:
+      // FIXME
+	  // Load -0.0
+	  // Compare
+	  // move to CR1
+	  // Negate -0.0
+	  // Compare
+	  // CROR
+	  // MFCR
+	  // Left-align
+	  // SRA ?
+      break;
+    }
+    return;
+  }
+
+  // Implement casts between values of the same type class (as determined by
+  // getClass) by using a register-to-register move.
+  if (SrcClass == DestClass) {
+	if (SrcClass <= cInt) {
+	  BuildMI(*BB, IP, PPC32::OR, 2, DestReg).addReg(SrcReg).addReg(SrcReg);
+	} else if (SrcClass == cFP && SrcTy == DestTy) {
+      BuildMI(*BB, IP, PPC32::FMR, 1, DestReg).addReg(SrcReg);
+    } else if (SrcClass == cFP) {
+      if (SrcTy == Type::FloatTy) {  // float -> double
+        assert(DestTy == Type::DoubleTy && "Unknown cFP member!");
+        BuildMI(*BB, IP, PPC32::FMR, 1, DestReg).addReg(SrcReg);
+      } else {                       // double -> float
+        assert(SrcTy == Type::DoubleTy && DestTy == Type::FloatTy &&
+               "Unknown cFP member!");
+		BuildMI(*BB, IP, PPC32::FRSP, 1, DestReg).addReg(SrcReg);
+      }
+    } else if (SrcClass == cLong) {
+	  BuildMI(*BB, IP, PPC32::OR, 2, DestReg).addReg(SrcReg).addReg(SrcReg);
+	  BuildMI(*BB, IP, PPC32::OR, 2, DestReg+1).addReg(SrcReg+1).addReg(SrcReg+1);
+    } else {
+      assert(0 && "Cannot handle this type of cast instruction!");
+      abort();
+    }
+    return;
+  }
+
+  // Handle cast of SMALLER int to LARGER int using a move with sign extension
+  // or zero extension, depending on whether the source type was signed.
+  if (SrcClass <= cInt && (DestClass <= cInt || DestClass == cLong) &&
+      SrcClass < DestClass) {
+    bool isLong = DestClass == cLong;
+    if (isLong) DestClass = cInt;
+
+    bool isUnsigned = SrcTy->isUnsigned() || SrcTy == Type::BoolTy;
+    if (SrcClass < cInt) {
+      if (isUnsigned) {
+    	unsigned shift = (SrcClass == cByte) ? 24 : 16;
+    	BuildMI(*BB, IP, PPC32::RLWINM, 4, DestReg).addReg(SrcReg).addZImm(0).addImm(shift).addImm(31);
+      } else {
+        BuildMI(*BB, IP, (SrcClass == cByte) ? PPC32::EXTSB : PPC32::EXTSH, 1, DestReg).addReg(SrcReg);
+	  }
+	} else {
+	  BuildMI(*BB, IP, PPC32::OR, 2, DestReg).addReg(SrcReg).addReg(SrcReg);
+	}
+
+    if (isLong) {  // Handle upper 32 bits as appropriate...
+      if (isUnsigned)     // Zero out top bits...
+        BuildMI(*BB, IP, PPC32::ADDI, 2, DestReg+1).addReg(PPC32::R0).addImm(0);
+      else                // Sign extend bottom half...
+        BuildMI(*BB, IP, PPC32::SRAWI, 2, DestReg+1).addReg(DestReg).addImm(31);
+    }
+    return;
+  }
+
+  // Special case long -> int ...
+  if (SrcClass == cLong && DestClass == cInt) {
+    BuildMI(*BB, IP, PPC32::OR, 2, DestReg).addReg(SrcReg).addReg(SrcReg);
+    return;
+  }
+  
+  // Handle cast of LARGER int to SMALLER int with a clear or sign extend
+  if ((SrcClass <= cInt || SrcClass == cLong) && DestClass <= cInt
+      && SrcClass > DestClass) {
+    bool isUnsigned = SrcTy->isUnsigned() || SrcTy == Type::BoolTy;
+	if (isUnsigned) {
+    	unsigned shift = (SrcClass == cByte) ? 24 : 16;
+    	BuildMI(*BB, IP, PPC32::RLWINM, 4, DestReg).addReg(SrcReg).addZImm(0).addImm(shift).addImm(31);
+	} else {
+        BuildMI(*BB, IP, (SrcClass == cByte) ? PPC32::EXTSB : PPC32::EXTSH, 1, DestReg).addReg(SrcReg);
+	}
+    return;
+  }
+
+  // Handle casts from integer to floating point now...
+  if (DestClass == cFP) {
+
+	// Emit a library call for long to float conversion
+	if (SrcClass == cLong) {
+		std::vector<ValueRecord> Args;
+		Args.push_back(ValueRecord(SrcReg, SrcTy));
+		MachineInstr *TheCall = BuildMI(PPC32::CALLpcrel, 1).addExternalSymbol("__floatdidf", true);
+		doCall(ValueRecord(DestReg, DestTy), TheCall, Args);
+		return;
+	}
+
+    unsigned TmpReg = makeAnotherReg(Type::IntTy);
+    switch (SrcTy->getPrimitiveID()) {
+    case Type::BoolTyID:
+    case Type::SByteTyID:
+      BuildMI(*BB, IP, PPC32::EXTSB, 1, TmpReg).addReg(SrcReg);
+      break;
+    case Type::UByteTyID:
+	  BuildMI(*BB, IP, PPC32::RLWINM, 4, TmpReg).addReg(SrcReg).addZImm(0).addImm(24).addImm(31);
+      break;
+    case Type::ShortTyID:
+      BuildMI(*BB, IP, PPC32::EXTSB, 1, TmpReg).addReg(SrcReg);
+      break;
+    case Type::UShortTyID:
+	  BuildMI(*BB, IP, PPC32::RLWINM, 4, TmpReg).addReg(SrcReg).addZImm(0).addImm(16).addImm(31);
+      break;
+	case Type::IntTyID:
+	  BuildMI(*BB, IP, PPC32::OR, 2, TmpReg).addReg(SrcReg).addReg(SrcReg);
+	  break;
+	case Type::UIntTyID:
+	  BuildMI(*BB, IP, PPC32::OR, 2, TmpReg).addReg(SrcReg).addReg(SrcReg);
+	  break;
+    default:  // No promotion needed...
+      break;
+    }
+    
+    SrcReg = TmpReg;
+	
+    // Spill the integer to memory and reload it from there.
+	// Also spill room for a special conversion constant
+	int ConstantFrameIndex = 
+      F->getFrameInfo()->CreateStackObject(Type::DoubleTy, TM.getTargetData());
+    int ValueFrameIdx =
+      F->getFrameInfo()->CreateStackObject(Type::DoubleTy, TM.getTargetData());
+
+	unsigned constantHi = makeAnotherReg(Type::IntTy);
+	unsigned constantLo = makeAnotherReg(Type::IntTy);
+	unsigned ConstF = makeAnotherReg(Type::DoubleTy);
+	unsigned TempF = makeAnotherReg(Type::DoubleTy);
+	
+    if (!SrcTy->isSigned()) {
+		BuildMI(*BB, IP, PPC32::ADDIS, 2, constantHi).addReg(PPC32::R0).addImm(0x4330);
+		BuildMI(*BB, IP, PPC32::ADDI, 2, constantLo).addReg(PPC32::R0).addImm(0);
+		addFrameReference(BuildMI(*BB, IP, PPC32::STW, 3).addReg(constantHi), ConstantFrameIndex);
+		addFrameReference(BuildMI(*BB, IP, PPC32::STW, 3).addReg(constantLo), ConstantFrameIndex, 4);
+		addFrameReference(BuildMI(*BB, IP, PPC32::STW, 3).addReg(constantHi), ValueFrameIdx);
+		addFrameReference(BuildMI(*BB, IP, PPC32::STW, 3).addReg(SrcReg), ValueFrameIdx, 4);
+		addFrameReference(BuildMI(*BB, IP, PPC32::LFD, 2, ConstF), ConstantFrameIndex);
+		addFrameReference(BuildMI(*BB, IP, PPC32::LFD, 2, TempF), ValueFrameIdx);
+		BuildMI(*BB, IP, PPC32::FSUB, 2, DestReg).addReg(TempF).addReg(ConstF);
+	} else {
+		unsigned TempLo = makeAnotherReg(Type::IntTy);
+		BuildMI(*BB, IP, PPC32::ADDIS, 2, constantHi).addReg(PPC32::R0).addImm(0x4330);
+		BuildMI(*BB, IP, PPC32::ADDIS, 2, constantLo).addReg(PPC32::R0).addImm(0x8000);
+		addFrameReference(BuildMI(*BB, IP, PPC32::STW, 3).addReg(constantHi), ConstantFrameIndex);
+		addFrameReference(BuildMI(*BB, IP, PPC32::STW, 3).addReg(constantLo), ConstantFrameIndex, 4);
+		addFrameReference(BuildMI(*BB, IP, PPC32::STW, 3).addReg(constantHi), ValueFrameIdx);
+		BuildMI(*BB, IP, PPC32::XORIS, 2, TempLo).addReg(SrcReg).addImm(0x8000);
+		addFrameReference(BuildMI(*BB, IP, PPC32::STW, 3).addReg(TempLo), ValueFrameIdx, 4);
+		addFrameReference(BuildMI(*BB, IP, PPC32::LFD, 2, ConstF), ConstantFrameIndex);
+		addFrameReference(BuildMI(*BB, IP, PPC32::LFD, 2, TempF), ValueFrameIdx);
+		BuildMI(*BB, IP, PPC32::FSUB, 2, DestReg).addReg(TempF).addReg(ConstF);
+	}
+    return;
+  }
+
+  // Handle casts from floating point to integer now...
+  if (SrcClass == cFP) {
+
+	// emit library call
+	if (DestClass == cLong) {
+		std::vector<ValueRecord> Args;
+		Args.push_back(ValueRecord(SrcReg, SrcTy));
+		MachineInstr *TheCall = BuildMI(PPC32::CALLpcrel, 1).addExternalSymbol("__fixdfdi", true);
+		doCall(ValueRecord(DestReg, DestTy), TheCall, Args);
+		return;
+	}
+
+    int ValueFrameIdx =
+      F->getFrameInfo()->CreateStackObject(Type::DoubleTy, TM.getTargetData());
+
+	// load into 32 bit value, and then truncate as necessary
+	// FIXME: This is wrong for unsigned dest types
+	//if (DestTy->isSigned()) {
+		unsigned TempReg = makeAnotherReg(Type::DoubleTy);
+		BuildMI(*BB, IP, PPC32::FCTIWZ, 1, TempReg).addReg(SrcReg);
+		addFrameReference(BuildMI(*BB, IP, PPC32::STFD, 3).addReg(TempReg), ValueFrameIdx);
+		addFrameReference(BuildMI(*BB, IP, PPC32::LWZ, 2, DestReg), ValueFrameIdx+4);
+	//} else {
+	//}
+	
+	// FIXME: Truncate return value
+    return;
+  }
+
+  // Anything we haven't handled already, we can't (yet) handle at all.
+  assert(0 && "Unhandled cast instruction!");
+  abort();
+}
+
+/// visitVANextInst - Implement the va_next instruction...
+///
+void ISel::visitVANextInst(VANextInst &I) {
+  unsigned VAList = getReg(I.getOperand(0));
+  unsigned DestReg = getReg(I);
+
+  unsigned Size;
+  switch (I.getArgType()->getPrimitiveID()) {
+  default:
+    std::cerr << I;
+    assert(0 && "Error: bad type for va_next instruction!");
+    return;
+  case Type::PointerTyID:
+  case Type::UIntTyID:
+  case Type::IntTyID:
+    Size = 4;
+    break;
+  case Type::ULongTyID:
+  case Type::LongTyID:
+  case Type::DoubleTyID:
+    Size = 8;
+    break;
+  }
+
+  // Increment the VAList pointer...
+  BuildMI(BB, PPC32::ADDI, 2, DestReg).addReg(VAList).addImm(Size);
+}
+
+void ISel::visitVAArgInst(VAArgInst &I) {
+  unsigned VAList = getReg(I.getOperand(0));
+  unsigned DestReg = getReg(I);
+
+  switch (I.getType()->getPrimitiveID()) {
+  default:
+    std::cerr << I;
+    assert(0 && "Error: bad type for va_next instruction!");
+    return;
+  case Type::PointerTyID:
+  case Type::UIntTyID:
+  case Type::IntTyID:
+    BuildMI(BB, PPC32::LWZ, 2, DestReg).addImm(0).addReg(VAList);
+    break;
+  case Type::ULongTyID:
+  case Type::LongTyID:
+    BuildMI(BB, PPC32::LWZ, 2, DestReg).addImm(0).addReg(VAList);
+    BuildMI(BB, PPC32::LWZ, 2, DestReg+1).addImm(4).addReg(VAList);
+    break;
+  case Type::DoubleTyID:
+    BuildMI(BB, PPC32::LFD, 2, DestReg).addImm(0).addReg(VAList);
+    break;
+  }
+}
+
+/// visitGetElementPtrInst - instruction-select GEP instructions
+///
+void ISel::visitGetElementPtrInst(GetElementPtrInst &I) {
+  unsigned outputReg = getReg(I);
+  emitGEPOperation(BB, BB->end(), I.getOperand(0),I.op_begin()+1, I.op_end(), outputReg);
+}
+
+void ISel::emitGEPOperation(MachineBasicBlock *MBB,
+                            MachineBasicBlock::iterator IP,
+                            Value *Src, User::op_iterator IdxBegin,
+                            User::op_iterator IdxEnd, unsigned TargetReg) {
+  const TargetData &TD = TM.getTargetData();
+  if (ConstantPointerRef *CPR = dyn_cast<ConstantPointerRef>(Src))
+    Src = CPR->getValue();
+
+  std::vector<Value*> GEPOps;
+  GEPOps.resize(IdxEnd-IdxBegin+1);
+  GEPOps[0] = Src;
+  std::copy(IdxBegin, IdxEnd, GEPOps.begin()+1);
+  
+  std::vector<const Type*> GEPTypes;
+  GEPTypes.assign(gep_type_begin(Src->getType(), IdxBegin, IdxEnd),
+                  gep_type_end(Src->getType(), IdxBegin, IdxEnd));
+
+  // Keep emitting instructions until we consume the entire GEP instruction.
+  while (!GEPOps.empty()) {
+      // It's an array or pointer access: [ArraySize x ElementType].
+      const SequentialType *SqTy = cast<SequentialType>(GEPTypes.back());
+      Value *idx = GEPOps.back();
+      GEPOps.pop_back();        // Consume a GEP operand
+      GEPTypes.pop_back();
+
+      // Many GEP instructions use a [cast (int/uint) to LongTy] as their
+      // operand on X86.  Handle this case directly now...
+      if (CastInst *CI = dyn_cast<CastInst>(idx))
+        if (CI->getOperand(0)->getType() == Type::IntTy ||
+            CI->getOperand(0)->getType() == Type::UIntTy)
+          idx = CI->getOperand(0);
+
+      // We want to add BaseReg to(idxReg * sizeof ElementType). First, we
+      // must find the size of the pointed-to type (Not coincidentally, the next
+      // type is the type of the elements in the array).
+      const Type *ElTy = SqTy->getElementType();
+      unsigned elementSize = TD.getTypeSize(ElTy);
+
+     if (elementSize == 1) {
+        // If the element size is 1, we don't have to multiply, just add
+        unsigned idxReg = getReg(idx, MBB, IP);
+        unsigned Reg = makeAnotherReg(Type::UIntTy);
+        BuildMI(*MBB, IP, PPC32::ADD, 2,TargetReg).addReg(Reg).addReg(idxReg);
+        --IP;            // Insert the next instruction before this one.
+        TargetReg = Reg; // Codegen the rest of the GEP into this
+      } else {
+        unsigned idxReg = getReg(idx, MBB, IP);
+        unsigned OffsetReg = makeAnotherReg(Type::UIntTy);
+
+        // Make sure we can back the iterator up to point to the first
+        // instruction emitted.
+        MachineBasicBlock::iterator BeforeIt = IP;
+        if (IP == MBB->begin())
+          BeforeIt = MBB->end();
+        else
+          --BeforeIt;
+        doMultiplyConst(MBB, IP, OffsetReg, Type::IntTy, idxReg, elementSize);
+
+        // Emit an ADD to add OffsetReg to the basePtr.
+        unsigned Reg = makeAnotherReg(Type::UIntTy);
+        BuildMI(*MBB, IP, PPC32::ADD, 2, TargetReg).addReg(Reg).addReg(OffsetReg);
+
+        // Step to the first instruction of the multiply.
+        if (BeforeIt == MBB->end())
+          IP = MBB->begin();
+        else
+          IP = ++BeforeIt;
+
+        TargetReg = Reg; // Codegen the rest of the GEP into this
+      }
+    }
+}
+
+/// visitAllocaInst - If this is a fixed size alloca, allocate space from the
+/// frame manager, otherwise do it the hard way.
+///
+void ISel::visitAllocaInst(AllocaInst &I) {
+  // If this is a fixed size alloca in the entry block for the function, we
+  // statically stack allocate the space, so we don't need to do anything here.
+  //
+  if (dyn_castFixedAlloca(&I)) return;
+  
+  // Find the data size of the alloca inst's getAllocatedType.
+  const Type *Ty = I.getAllocatedType();
+  unsigned TySize = TM.getTargetData().getTypeSize(Ty);
+
+  // Create a register to hold the temporary result of multiplying the type size
+  // constant by the variable amount.
+  unsigned TotalSizeReg = makeAnotherReg(Type::UIntTy);
+  unsigned SrcReg1 = getReg(I.getArraySize());
+  
+  // TotalSizeReg = mul <numelements>, <TypeSize>
+  MachineBasicBlock::iterator MBBI = BB->end();
+  doMultiplyConst(BB, MBBI, TotalSizeReg, Type::UIntTy, SrcReg1, TySize);
+
+  // AddedSize = add <TotalSizeReg>, 15
+  unsigned AddedSizeReg = makeAnotherReg(Type::UIntTy);
+  BuildMI(BB, PPC32::ADD, 2, AddedSizeReg).addReg(TotalSizeReg).addImm(15);
+
+  // AlignedSize = and <AddedSize>, ~15
+  unsigned AlignedSize = makeAnotherReg(Type::UIntTy);
+  BuildMI(BB, PPC32::RLWNM, 4, AlignedSize).addReg(AddedSizeReg).addImm(0).addImm(0).addImm(27);
+  
+  // Subtract size from stack pointer, thereby allocating some space.
+  BuildMI(BB, PPC32::SUB, 2, PPC32::R1).addReg(PPC32::R1).addReg(AlignedSize);
+
+  // Put a pointer to the space into the result register, by copying
+  // the stack pointer.
+  BuildMI(BB, PPC32::OR, 2, getReg(I)).addReg(PPC32::R1).addReg(PPC32::R1);
+
+  // Inform the Frame Information that we have just allocated a variable-sized
+  // object.
+  F->getFrameInfo()->CreateVariableSizedObject();
+}
+
+/// visitMallocInst - Malloc instructions are code generated into direct calls
+/// to the library malloc.
+///
+void ISel::visitMallocInst(MallocInst &I) {
+  unsigned AllocSize = TM.getTargetData().getTypeSize(I.getAllocatedType());
+  unsigned Arg;
+
+  if (ConstantUInt *C = dyn_cast<ConstantUInt>(I.getOperand(0))) {
+    Arg = getReg(ConstantUInt::get(Type::UIntTy, C->getValue() * AllocSize));
+  } else {
+    Arg = makeAnotherReg(Type::UIntTy);
+    unsigned Op0Reg = getReg(I.getOperand(0));
+    MachineBasicBlock::iterator MBBI = BB->end();
+    doMultiplyConst(BB, MBBI, Arg, Type::UIntTy, Op0Reg, AllocSize);
+  }
+
+  std::vector<ValueRecord> Args;
+  Args.push_back(ValueRecord(Arg, Type::UIntTy));
+  MachineInstr *TheCall = BuildMI(PPC32::CALLpcrel, 1).addExternalSymbol("malloc", true);
+  doCall(ValueRecord(getReg(I), I.getType()), TheCall, Args);
+}
+
+
+/// visitFreeInst - Free instructions are code gen'd to call the free libc
+/// function.
+///
+void ISel::visitFreeInst(FreeInst &I) {
+  std::vector<ValueRecord> Args;
+  Args.push_back(ValueRecord(I.getOperand(0)));
+  MachineInstr *TheCall = BuildMI(PPC32::CALLpcrel, 1).addExternalSymbol("free", true);
+  doCall(ValueRecord(0, Type::VoidTy), TheCall, Args);
+}
+   
+/// createPPC32SimpleInstructionSelector - This pass converts an LLVM function
+/// into a machine code representation is a very simple peep-hole fashion.  The
+/// generated code sucks but the implementation is nice and simple.
+///
+FunctionPass *llvm::createPPCSimpleInstructionSelector(TargetMachine &TM) {
+  return new ISel(TM);
+}