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authorMisha Brukman <brukman+llvm@gmail.com>2004-07-26 18:43:11 +0000
committerMisha Brukman <brukman+llvm@gmail.com>2004-07-26 18:43:11 +0000
commitc6d398abbb462dc3453e2027886ec01c96d3e651 (patch)
tree1a3a5c9b78941a8083eb8b7af83e302086f81a07 /lib/Target/X86/InstSelectSimple.cpp
parentb097f216b0fe35303f519fda6cf0dceda0587d44 (diff)
Renamed files to have the `X86' prefix for uniqueness purposes.
All CVS history was renamed, the *,v were copied over. No worries. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@15238 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/Target/X86/InstSelectSimple.cpp')
-rw-r--r--lib/Target/X86/InstSelectSimple.cpp3907
1 files changed, 0 insertions, 3907 deletions
diff --git a/lib/Target/X86/InstSelectSimple.cpp b/lib/Target/X86/InstSelectSimple.cpp
deleted file mode 100644
index 4b43896d37..0000000000
--- a/lib/Target/X86/InstSelectSimple.cpp
+++ /dev/null
@@ -1,3907 +0,0 @@
-//===-- InstSelectSimple.cpp - A simple instruction selector for x86 ------===//
-//
-// 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.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file defines a simple peephole instruction selector for the x86 target
-//
-//===----------------------------------------------------------------------===//
-
-#include "X86.h"
-#include "X86InstrBuilder.h"
-#include "X86InstrInfo.h"
-#include "llvm/Constants.h"
-#include "llvm/DerivedTypes.h"
-#include "llvm/Function.h"
-#include "llvm/Instructions.h"
-#include "llvm/Pass.h"
-#include "llvm/CodeGen/IntrinsicLowering.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"
-#include "Support/Statistic.h"
-using namespace llvm;
-
-namespace {
- Statistic<>
- NumFPKill("x86-codegen", "Number of FP_REG_KILL instructions added");
-
- /// TypeClass - Used by the X86 backend to group LLVM types by their basic X86
- /// 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->getTypeID()) {
- 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 bytes.
-static inline TypeClass getClassB(const Type *Ty) {
- if (Ty == Type::BoolTy) return cByte;
- 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();
-
- // Insert the FP_REG_KILL instructions into blocks that need them.
- InsertFPRegKills();
-
- 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 "X86 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();
-
- /// InsertFPRegKills - Insert FP_REG_KILL instructions into basic blocks
- /// that need them. This only occurs due to the floating point stackifier
- /// not being aggressive enough to handle arbitrary global stackification.
- ///
- void InsertFPRegKills();
-
- // Visitation methods for various instructions. These methods simply emit
- // fixed X86 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);
-
- /// getAddressingMode - Get the addressing mode to use to address the
- /// specified value. The returned value should be used with addFullAddress.
- void getAddressingMode(Value *Addr, unsigned &BaseReg, unsigned &Scale,
- unsigned &IndexReg, unsigned &Disp);
-
-
- /// getGEPIndex - This is used to fold GEP instructions into X86 addressing
- /// expressions.
- void getGEPIndex(MachineBasicBlock *MBB, MachineBasicBlock::iterator IP,
- std::vector<Value*> &GEPOps,
- std::vector<const Type*> &GEPTypes, unsigned &BaseReg,
- unsigned &Scale, unsigned &IndexReg, unsigned &Disp);
-
- /// isGEPFoldable - Return true if the specified GEP can be completely
- /// folded into the addressing mode of a load/store or lea instruction.
- bool isGEPFoldable(MachineBasicBlock *MBB,
- Value *Src, User::op_iterator IdxBegin,
- User::op_iterator IdxEnd, unsigned &BaseReg,
- unsigned &Scale, unsigned &IndexReg, unsigned &Disp);
-
- /// 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 emitUCOMr(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 X86RegisterInfo*>(TM.getRegisterInfo()) &&
- "Current target doesn't have X86 reg info??");
- const X86RegisterInfo *MRI =
- static_cast<const X86RegisterInfo*>(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 (CastInst *CI = dyn_cast<CastInst>(V)) {
- // Do not emit noop casts at all, unless it's a double -> float cast.
- if (getClassB(CI->getType()) == getClassB(CI->getOperand(0)->getType()) &&
- (CI->getType() != Type::FloatTy ||
- CI->getOperand(0)->getType() != Type::DoubleTy))
- return getReg(CI->getOperand(0), MBB, IPt);
- } else if (AllocaInst *AI = dyn_castFixedAlloca(V)) {
- // If the alloca address couldn't be folded into the instruction addressing,
- // emit an explicit LEA as appropriate.
- unsigned Reg = makeAnotherReg(V->getType());
- unsigned FI = getFixedSizedAllocaFI(AI);
- addFrameReference(BuildMI(*MBB, IPt, X86::LEA32r, 4, Reg), FI);
- 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();
- BuildMI(*MBB, IP, X86::MOV32ri, 1, R).addImm(Val & 0xFFFFFFFF);
- BuildMI(*MBB, IP, X86::MOV32ri, 1, R+1).addImm(Val >> 32);
- return;
- }
-
- assert(Class <= cInt && "Type not handled yet!");
-
- static const unsigned IntegralOpcodeTab[] = {
- X86::MOV8ri, X86::MOV16ri, X86::MOV32ri
- };
-
- if (C->getType() == Type::BoolTy) {
- BuildMI(*MBB, IP, X86::MOV8ri, 1, R).addImm(C == ConstantBool::True);
- } else {
- ConstantInt *CI = cast<ConstantInt>(C);
- BuildMI(*MBB, IP, IntegralOpcodeTab[Class],1,R).addImm(CI->getRawValue());
- }
- } else if (ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
- if (CFP->isExactlyValue(+0.0))
- BuildMI(*MBB, IP, X86::FLD0, 0, R);
- else if (CFP->isExactlyValue(+1.0))
- BuildMI(*MBB, IP, X86::FLD1, 0, R);
- else {
- // Otherwise 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 ? X86::FLD32m : X86::FLD64m;
- addConstantPoolReference(BuildMI(*MBB, IP, LoadOpcode, 4, R), CPI);
- }
-
- } else if (isa<ConstantPointerNull>(C)) {
- // Copy zero (null pointer) to the register.
- BuildMI(*MBB, IP, X86::MOV32ri, 1, R).addImm(0);
- } else if (GlobalValue *GV = dyn_cast<GlobalValue>(C)) {
- BuildMI(*MBB, IP, X86::MOV32ri, 1, R).addGlobalAddress(GV);
- } 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.
-///
-void ISel::LoadArgumentsToVirtualRegs(Function &Fn) {
- // Emit instructions to load the arguments... On entry to a function on the
- // X86, the stack frame looks like this:
- //
- // [ESP] -- return address
- // [ESP + 4] -- first argument (leftmost lexically)
- // [ESP + 8] -- second argument, if first argument is four bytes in size
- // ...
- //
- unsigned ArgOffset = 0; // Frame mechanisms handle retaddr slot
- 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);
- addFrameReference(BuildMI(BB, X86::MOV8rm, 4, Reg), FI);
- }
- break;
- case cShort:
- if (ArgLive) {
- FI = MFI->CreateFixedObject(2, ArgOffset);
- addFrameReference(BuildMI(BB, X86::MOV16rm, 4, Reg), FI);
- }
- break;
- case cInt:
- if (ArgLive) {
- FI = MFI->CreateFixedObject(4, ArgOffset);
- addFrameReference(BuildMI(BB, X86::MOV32rm, 4, Reg), FI);
- }
- break;
- case cLong:
- if (ArgLive) {
- FI = MFI->CreateFixedObject(8, ArgOffset);
- addFrameReference(BuildMI(BB, X86::MOV32rm, 4, Reg), FI);
- addFrameReference(BuildMI(BB, X86::MOV32rm, 4, Reg+1), FI, 4);
- }
- ArgOffset += 4; // longs require 4 additional bytes
- break;
- case cFP:
- if (ArgLive) {
- unsigned Opcode;
- if (I->getType() == Type::FloatTy) {
- Opcode = X86::FLD32m;
- FI = MFI->CreateFixedObject(4, ArgOffset);
- } else {
- Opcode = X86::FLD64m;
- FI = MFI->CreateFixedObject(8, ArgOffset);
- }
- addFrameReference(BuildMI(BB, Opcode, 4, Reg), FI);
- }
- if (I->getType() == Type::DoubleTy)
- ArgOffset += 4; // doubles require 4 additional bytes
- break;
- default:
- assert(0 && "Unhandled argument type!");
- }
- ArgOffset += 4; // Each argument takes at least 4 bytes on the stack...
- }
-
- // 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,
- X86::PHI, PN->getNumOperands(), PHIReg);
-
- MachineInstr *LongPhiMI = 0;
- if (PN->getType() == Type::LongTy || PN->getType() == Type::ULongTy)
- LongPhiMI = BuildMI(MBB, PHIInsertPoint,
- X86::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))) {
- // 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() == X86::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;
- }
- }
-}
-
-/// RequiresFPRegKill - The floating point stackifier pass cannot insert
-/// compensation code on critical edges. As such, it requires that we kill all
-/// FP registers on the exit from any blocks that either ARE critical edges, or
-/// branch to a block that has incoming critical edges.
-///
-/// Note that this kill instruction will eventually be eliminated when
-/// restrictions in the stackifier are relaxed.
-///
-static bool RequiresFPRegKill(const MachineBasicBlock *MBB) {
-#if 0
- const BasicBlock *BB = MBB->getBasicBlock ();
- for (succ_const_iterator SI = succ_begin(BB), E = succ_end(BB); SI!=E; ++SI) {
- const BasicBlock *Succ = *SI;
- pred_const_iterator PI = pred_begin(Succ), PE = pred_end(Succ);
- ++PI; // Block have at least one predecessory
- if (PI != PE) { // If it has exactly one, this isn't crit edge
- // If this block has more than one predecessor, check all of the
- // predecessors to see if they have multiple successors. If so, then the
- // block we are analyzing needs an FPRegKill.
- for (PI = pred_begin(Succ); PI != PE; ++PI) {
- const BasicBlock *Pred = *PI;
- succ_const_iterator SI2 = succ_begin(Pred);
- ++SI2; // There must be at least one successor of this block.
- if (SI2 != succ_end(Pred))
- return true; // Yes, we must insert the kill on this edge.
- }
- }
- }
- // If we got this far, there is no need to insert the kill instruction.
- return false;
-#else
- return true;
-#endif
-}
-
-// InsertFPRegKills - Insert FP_REG_KILL instructions into basic blocks that
-// need them. This only occurs due to the floating point stackifier not being
-// aggressive enough to handle arbitrary global stackification.
-//
-// Currently we insert an FP_REG_KILL instruction into each block that uses or
-// defines a floating point virtual register.
-//
-// When the global register allocators (like linear scan) finally update live
-// variable analysis, we can keep floating point values in registers across
-// portions of the CFG that do not involve critical edges. This will be a big
-// win, but we are waiting on the global allocators before we can do this.
-//
-// With a bit of work, the floating point stackifier pass can be enhanced to
-// break critical edges as needed (to make a place to put compensation code),
-// but this will require some infrastructure improvements as well.
-//
-void ISel::InsertFPRegKills() {
- SSARegMap &RegMap = *F->getSSARegMap();
-
- for (MachineFunction::iterator BB = F->begin(), E = F->end(); BB != E; ++BB) {
- for (MachineBasicBlock::iterator I = BB->begin(), E = BB->end(); I!=E; ++I)
- for (unsigned i = 0, e = I->getNumOperands(); i != e; ++i) {
- MachineOperand& MO = I->getOperand(i);
- if (MO.isRegister() && MO.getReg()) {
- unsigned Reg = MO.getReg();
- if (MRegisterInfo::isVirtualRegister(Reg))
- if (RegMap.getRegClass(Reg)->getSize() == 10)
- goto UsesFPReg;
- }
- }
- // If we haven't found an FP register use or def in this basic block, check
- // to see if any of our successors has an FP PHI node, which will cause a
- // copy to be inserted into this block.
- for (MachineBasicBlock::const_succ_iterator SI = BB->succ_begin(),
- SE = BB->succ_end(); SI != SE; ++SI) {
- MachineBasicBlock *SBB = *SI;
- for (MachineBasicBlock::iterator I = SBB->begin();
- I != SBB->end() && I->getOpcode() == X86::PHI; ++I) {
- if (RegMap.getRegClass(I->getOperand(0).getReg())->getSize() == 10)
- goto UsesFPReg;
- }
- }
- continue;
- UsesFPReg:
- // Okay, this block uses an FP register. If the block has successors (ie,
- // it's not an unwind/return), insert the FP_REG_KILL instruction.
- if (BB->succ_size () && RequiresFPRegKill(BB)) {
- BuildMI(*BB, BB->getFirstTerminator(), X86::FP_REG_KILL, 0);
- ++NumFPKill;
- }
- }
-}
-
-
-void ISel::getAddressingMode(Value *Addr, unsigned &BaseReg, unsigned &Scale,
- unsigned &IndexReg, unsigned &Disp) {
- BaseReg = 0; Scale = 1; IndexReg = 0; Disp = 0;
- if (GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(Addr)) {
- if (isGEPFoldable(BB, GEP->getOperand(0), GEP->op_begin()+1, GEP->op_end(),
- BaseReg, Scale, IndexReg, Disp))
- return;
- } else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(Addr)) {
- if (CE->getOpcode() == Instruction::GetElementPtr)
- if (isGEPFoldable(BB, CE->getOperand(0), CE->op_begin()+1, CE->op_end(),
- BaseReg, Scale, IndexReg, Disp))
- return;
- }
-
- // If it's not foldable, reset addr mode.
- BaseReg = getReg(Addr);
- Scale = 1; IndexReg = 0; Disp = 0;
-}
-
-// 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. 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)) &&
- (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;
- }
-}
-
-// LLVM -> X86 signed X86 unsigned
-// ----- ---------- ------------
-// seteq -> sete sete
-// setne -> setne setne
-// setlt -> setl setb
-// setge -> setge setae
-// setgt -> setg seta
-// setle -> setle setbe
-// ----
-// sets // Used by comparison with 0 optimization
-// setns
-static const unsigned SetCCOpcodeTab[2][8] = {
- { X86::SETEr, X86::SETNEr, X86::SETBr, X86::SETAEr, X86::SETAr, X86::SETBEr,
- 0, 0 },
- { X86::SETEr, X86::SETNEr, X86::SETLr, X86::SETGEr, X86::SETGr, X86::SETLEr,
- X86::SETSr, X86::SETNSr },
-};
-
-/// emitUCOMr - In the future when we support processors before the P6, this
-/// wraps the logic for emitting an FUCOMr vs FUCOMIr.
-void ISel::emitUCO