diff --git a/lib/Target/X86/MachineCodeEmitter.cpp b/lib/Target/X86/MachineCodeEmitter.cpp deleted file mode 100644 index 07b1a0bcc3f..00000000000 --- a/lib/Target/X86/MachineCodeEmitter.cpp +++ /dev/null @@ -1,558 +0,0 @@ -//===-- X86/MachineCodeEmitter.cpp - Convert X86 code to machine code -----===// -// -// This file contains the pass that transforms the X86 machine instructions into -// actual executable machine code. -// -//===----------------------------------------------------------------------===// - -#include "X86TargetMachine.h" -#include "X86.h" -#include "llvm/PassManager.h" -#include "llvm/CodeGen/MachineCodeEmitter.h" -#include "llvm/CodeGen/MachineFunctionPass.h" -#include "llvm/CodeGen/MachineInstr.h" -#include "llvm/Value.h" - -namespace { - class JITResolver { - MachineCodeEmitter &MCE; - - // LazyCodeGenMap - Keep track of call sites for functions that are to be - // lazily resolved. - std::map LazyCodeGenMap; - - // LazyResolverMap - Keep track of the lazy resolver created for a - // particular function so that we can reuse them if necessary. - std::map LazyResolverMap; - public: - JITResolver(MachineCodeEmitter &mce) : MCE(mce) {} - unsigned getLazyResolver(Function *F); - unsigned addFunctionReference(unsigned Address, Function *F); - - private: - unsigned emitStubForFunction(Function *F); - static void CompilationCallback(); - unsigned resolveFunctionReference(unsigned RetAddr); - }; - - JITResolver *TheJITResolver; -} - - -/// addFunctionReference - This method is called when we need to emit the -/// address of a function that has not yet been emitted, so we don't know the -/// address. Instead, we emit a call to the CompilationCallback method, and -/// keep track of where we are. -/// -unsigned JITResolver::addFunctionReference(unsigned Address, Function *F) { - LazyCodeGenMap[Address] = F; - return (intptr_t)&JITResolver::CompilationCallback; -} - -unsigned JITResolver::resolveFunctionReference(unsigned RetAddr) { - std::map::iterator I = LazyCodeGenMap.find(RetAddr); - assert(I != LazyCodeGenMap.end() && "Not in map!"); - Function *F = I->second; - LazyCodeGenMap.erase(I); - return MCE.forceCompilationOf(F); -} - -unsigned JITResolver::getLazyResolver(Function *F) { - std::map::iterator I = LazyResolverMap.lower_bound(F); - if (I != LazyResolverMap.end() && I->first == F) return I->second; - -//std::cerr << "Getting lazy resolver for : " << ((Value*)F)->getName() << "\n"; - - unsigned Stub = emitStubForFunction(F); - LazyResolverMap.insert(I, std::make_pair(F, Stub)); - return Stub; -} - -void JITResolver::CompilationCallback() { - unsigned *StackPtr = (unsigned*)__builtin_frame_address(0); - unsigned RetAddr = (unsigned)__builtin_return_address(0); - - assert(StackPtr[1] == RetAddr && - "Could not find return address on the stack!"); - bool isStub = ((unsigned char*)RetAddr)[0] == 0xCD; // Interrupt marker? - - // The call instruction should have pushed the return value onto the stack... - RetAddr -= 4; // Backtrack to the reference itself... - -#if 0 - DEBUG(std::cerr << "In callback! Addr=0x" << std::hex << RetAddr - << " ESP=0x" << (unsigned)StackPtr << std::dec - << ": Resolving call to function: " - << TheVM->getFunctionReferencedName((void*)RetAddr) << "\n"); -#endif - - // Sanity check to make sure this really is a call instruction... - assert(((unsigned char*)RetAddr)[-1] == 0xE8 && "Not a call instr!"); - - unsigned NewVal = TheJITResolver->resolveFunctionReference(RetAddr); - - // Rewrite the call target... so that we don't fault every time we execute - // the call. - *(unsigned*)RetAddr = NewVal-RetAddr-4; - - if (isStub) { - // If this is a stub, rewrite the call into an unconditional branch - // instruction so that two return addresses are not pushed onto the stack - // when the requested function finally gets called. This also makes the - // 0xCD byte (interrupt) dead, so the marker doesn't effect anything. - ((unsigned char*)RetAddr)[-1] = 0xE9; - } - - // Change the return address to reexecute the call instruction... - StackPtr[1] -= 5; -} - -/// emitStubForFunction - This method is used by the JIT when it needs to emit -/// the address of a function for a function whose code has not yet been -/// generated. In order to do this, it generates a stub which jumps to the lazy -/// function compiler, which will eventually get fixed to call the function -/// directly. -/// -unsigned JITResolver::emitStubForFunction(Function *F) { - MCE.startFunctionStub(*F, 6); - MCE.emitByte(0xE8); // Call with 32 bit pc-rel destination... - - unsigned Address = addFunctionReference(MCE.getCurrentPCValue(), F); - MCE.emitWord(Address-MCE.getCurrentPCValue()-4); - - MCE.emitByte(0xCD); // Interrupt - Just a marker identifying the stub! - return (intptr_t)MCE.finishFunctionStub(*F); -} - - - -namespace { - class Emitter : public MachineFunctionPass { - const X86InstrInfo *II; - MachineCodeEmitter &MCE; - std::map BasicBlockAddrs; - std::vector > BBRefs; - public: - Emitter(MachineCodeEmitter &mce) : II(0), MCE(mce) {} - - bool runOnMachineFunction(MachineFunction &MF); - - virtual const char *getPassName() const { - return "X86 Machine Code Emitter"; - } - - private: - void emitBasicBlock(MachineBasicBlock &MBB); - void emitInstruction(MachineInstr &MI); - - void emitPCRelativeBlockAddress(BasicBlock *BB); - void emitMaybePCRelativeValue(unsigned Address, bool isPCRelative); - void emitGlobalAddressForCall(GlobalValue *GV); - void emitGlobalAddressForPtr(GlobalValue *GV); - - void emitRegModRMByte(unsigned ModRMReg, unsigned RegOpcodeField); - void emitSIBByte(unsigned SS, unsigned Index, unsigned Base); - void emitConstant(unsigned Val, unsigned Size); - - void emitMemModRMByte(const MachineInstr &MI, - unsigned Op, unsigned RegOpcodeField); - - }; -} - -/// addPassesToEmitMachineCode - Add passes to the specified pass manager to get -/// machine code emitted. This uses a MAchineCodeEmitter object to handle -/// actually outputting the machine code and resolving things like the address -/// of functions. This method should returns true if machine code emission is -/// not supported. -/// -bool X86TargetMachine::addPassesToEmitMachineCode(PassManager &PM, - MachineCodeEmitter &MCE) { - PM.add(new Emitter(MCE)); - return false; -} - -bool Emitter::runOnMachineFunction(MachineFunction &MF) { - II = &((X86TargetMachine&)MF.getTarget()).getInstrInfo(); - - MCE.startFunction(MF); - MCE.emitConstantPool(MF.getConstantPool()); - for (MachineFunction::iterator I = MF.begin(), E = MF.end(); I != E; ++I) - emitBasicBlock(*I); - MCE.finishFunction(MF); - - // Resolve all forward branches now... - for (unsigned i = 0, e = BBRefs.size(); i != e; ++i) { - unsigned Location = BasicBlockAddrs[BBRefs[i].first]; - unsigned Ref = BBRefs[i].second; - *(unsigned*)Ref = Location-Ref-4; - } - BBRefs.clear(); - BasicBlockAddrs.clear(); - return false; -} - -void Emitter::emitBasicBlock(MachineBasicBlock &MBB) { - if (uint64_t Addr = MCE.getCurrentPCValue()) - BasicBlockAddrs[MBB.getBasicBlock()] = Addr; - - for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end(); I != E; ++I) - emitInstruction(**I); -} - - -/// emitPCRelativeBlockAddress - This method emits the PC relative address of -/// the specified basic block, or if the basic block hasn't been emitted yet -/// (because this is a forward branch), it keeps track of the information -/// necessary to resolve this address later (and emits a dummy value). -/// -void Emitter::emitPCRelativeBlockAddress(BasicBlock *BB) { - // FIXME: Emit backward branches directly - BBRefs.push_back(std::make_pair(BB, MCE.getCurrentPCValue())); - MCE.emitWord(0); // Emit a dummy value -} - -/// emitMaybePCRelativeValue - Emit a 32-bit address which may be PC relative. -/// -void Emitter::emitMaybePCRelativeValue(unsigned Address, bool isPCRelative) { - if (isPCRelative) - MCE.emitWord(Address-MCE.getCurrentPCValue()-4); - else - MCE.emitWord(Address); -} - -/// emitGlobalAddressForCall - Emit the specified address to the code stream -/// assuming this is part of a function call, which is PC relative. -/// -void Emitter::emitGlobalAddressForCall(GlobalValue *GV) { - // Get the address from the backend... - unsigned Address = MCE.getGlobalValueAddress(GV); - - // If the machine code emitter doesn't know what the address IS yet, we have - // to take special measures. - // - if (Address == 0) { - // FIXME: this is JIT specific! - if (TheJITResolver == 0) - TheJITResolver = new JITResolver(MCE); - Address = TheJITResolver->addFunctionReference(MCE.getCurrentPCValue(), - (Function*)GV); - } - emitMaybePCRelativeValue(Address, true); -} - -/// emitGlobalAddress - Emit the specified address to the code stream assuming -/// this is part of a "take the address of a global" instruction, which is not -/// PC relative. -/// -void Emitter::emitGlobalAddressForPtr(GlobalValue *GV) { - // Get the address from the backend... - unsigned Address = MCE.getGlobalValueAddress(GV); - - // If the machine code emitter doesn't know what the address IS yet, we have - // to take special measures. - // - if (Address == 0) { - // FIXME: this is JIT specific! - if (TheJITResolver == 0) - TheJITResolver = new JITResolver(MCE); - Address = TheJITResolver->getLazyResolver((Function*)GV); - } - - emitMaybePCRelativeValue(Address, false); -} - - - - -namespace N86 { // Native X86 Register numbers... - enum { - EAX = 0, ECX = 1, EDX = 2, EBX = 3, ESP = 4, EBP = 5, ESI = 6, EDI = 7 - }; -} - - -// getX86RegNum - This function maps LLVM register identifiers to their X86 -// specific numbering, which is used in various places encoding instructions. -// -static unsigned getX86RegNum(unsigned RegNo) { - switch(RegNo) { - case X86::EAX: case X86::AX: case X86::AL: return N86::EAX; - case X86::ECX: case X86::CX: case X86::CL: return N86::ECX; - case X86::EDX: case X86::DX: case X86::DL: return N86::EDX; - case X86::EBX: case X86::BX: case X86::BL: return N86::EBX; - case X86::ESP: case X86::SP: case X86::AH: return N86::ESP; - case X86::EBP: case X86::BP: case X86::CH: return N86::EBP; - case X86::ESI: case X86::SI: case X86::DH: return N86::ESI; - case X86::EDI: case X86::DI: case X86::BH: return N86::EDI; - - case X86::ST0: case X86::ST1: case X86::ST2: case X86::ST3: - case X86::ST4: case X86::ST5: case X86::ST6: case X86::ST7: - return RegNo-X86::ST0; - default: - assert(RegNo >= MRegisterInfo::FirstVirtualRegister && - "Unknown physical register!"); - assert(0 && "Register allocator hasn't allocated reg correctly yet!"); - return 0; - } -} - -inline static unsigned char ModRMByte(unsigned Mod, unsigned RegOpcode, - unsigned RM) { - assert(Mod < 4 && RegOpcode < 8 && RM < 8 && "ModRM Fields out of range!"); - return RM | (RegOpcode << 3) | (Mod << 6); -} - -void Emitter::emitRegModRMByte(unsigned ModRMReg, unsigned RegOpcodeFld){ - MCE.emitByte(ModRMByte(3, RegOpcodeFld, getX86RegNum(ModRMReg))); -} - -void Emitter::emitSIBByte(unsigned SS, unsigned Index, unsigned Base) { - // SIB byte is in the same format as the ModRMByte... - MCE.emitByte(ModRMByte(SS, Index, Base)); -} - -void Emitter::emitConstant(unsigned Val, unsigned Size) { - // Output the constant in little endian byte order... - for (unsigned i = 0; i != Size; ++i) { - MCE.emitByte(Val & 255); - Val >>= 8; - } -} - -static bool isDisp8(int Value) { - return Value == (signed char)Value; -} - -void Emitter::emitMemModRMByte(const MachineInstr &MI, - unsigned Op, unsigned RegOpcodeField) { - const MachineOperand &Disp = MI.getOperand(Op+3); - if (MI.getOperand(Op).isConstantPoolIndex()) { - // Emit a direct address reference [disp32] where the displacement of the - // constant pool entry is controlled by the MCE. - MCE.emitByte(ModRMByte(0, RegOpcodeField, 5)); - unsigned Index = MI.getOperand(Op).getConstantPoolIndex(); - unsigned Address = MCE.getConstantPoolEntryAddress(Index); - MCE.emitWord(Address+Disp.getImmedValue()); - return; - } - - const MachineOperand &BaseReg = MI.getOperand(Op); - const MachineOperand &Scale = MI.getOperand(Op+1); - const MachineOperand &IndexReg = MI.getOperand(Op+2); - - // Is a SIB byte needed? - if (IndexReg.getReg() == 0 && BaseReg.getReg() != X86::ESP) { - if (BaseReg.getReg() == 0) { // Just a displacement? - // Emit special case [disp32] encoding - MCE.emitByte(ModRMByte(0, RegOpcodeField, 5)); - emitConstant(Disp.getImmedValue(), 4); - } else { - unsigned BaseRegNo = getX86RegNum(BaseReg.getReg()); - if (Disp.getImmedValue() == 0 && BaseRegNo != N86::EBP) { - // Emit simple indirect register encoding... [EAX] f.e. - MCE.emitByte(ModRMByte(0, RegOpcodeField, BaseRegNo)); - } else if (isDisp8(Disp.getImmedValue())) { - // Emit the disp8 encoding... [REG+disp8] - MCE.emitByte(ModRMByte(1, RegOpcodeField, BaseRegNo)); - emitConstant(Disp.getImmedValue(), 1); - } else { - // Emit the most general non-SIB encoding: [REG+disp32] - MCE.emitByte(ModRMByte(2, RegOpcodeField, BaseRegNo)); - emitConstant(Disp.getImmedValue(), 4); - } - } - - } else { // We need a SIB byte, so start by outputting the ModR/M byte first - assert(IndexReg.getReg() != X86::ESP && "Cannot use ESP as index reg!"); - - bool ForceDisp32 = false; - bool ForceDisp8 = false; - if (BaseReg.getReg() == 0) { - // If there is no base register, we emit the special case SIB byte with - // MOD=0, BASE=5, to JUST get the index, scale, and displacement. - MCE.emitByte(ModRMByte(0, RegOpcodeField, 4)); - ForceDisp32 = true; - } else if (Disp.getImmedValue() == 0 && BaseReg.getReg() != X86::EBP) { - // Emit no displacement ModR/M byte - MCE.emitByte(ModRMByte(0, RegOpcodeField, 4)); - } else if (isDisp8(Disp.getImmedValue())) { - // Emit the disp8 encoding... - MCE.emitByte(ModRMByte(1, RegOpcodeField, 4)); - ForceDisp8 = true; // Make sure to force 8 bit disp if Base=EBP - } else { - // Emit the normal disp32 encoding... - MCE.emitByte(ModRMByte(2, RegOpcodeField, 4)); - } - - // Calculate what the SS field value should be... - static const unsigned SSTable[] = { ~0, 0, 1, ~0, 2, ~0, ~0, ~0, 3 }; - unsigned SS = SSTable[Scale.getImmedValue()]; - - if (BaseReg.getReg() == 0) { - // Handle the SIB byte for the case where there is no base. The - // displacement has already been output. - assert(IndexReg.getReg() && "Index register must be specified!"); - emitSIBByte(SS, getX86RegNum(IndexReg.getReg()), 5); - } else { - unsigned BaseRegNo = getX86RegNum(BaseReg.getReg()); - unsigned IndexRegNo; - if (IndexReg.getReg()) - IndexRegNo = getX86RegNum(IndexReg.getReg()); - else - IndexRegNo = 4; // For example [ESP+1*+4] - emitSIBByte(SS, IndexRegNo, BaseRegNo); - } - - // Do we need to output a displacement? - if (Disp.getImmedValue() != 0 || ForceDisp32 || ForceDisp8) { - if (!ForceDisp32 && isDisp8(Disp.getImmedValue())) - emitConstant(Disp.getImmedValue(), 1); - else - emitConstant(Disp.getImmedValue(), 4); - } - } -} - -static unsigned sizeOfPtr(const TargetInstrDescriptor &Desc) { - switch (Desc.TSFlags & X86II::ArgMask) { - case X86II::Arg8: return 1; - case X86II::Arg16: return 2; - case X86II::Arg32: return 4; - case X86II::ArgF32: return 4; - case X86II::ArgF64: return 8; - case X86II::ArgF80: return 10; - default: assert(0 && "Memory size not set!"); - return 0; - } -} - -void Emitter::emitInstruction(MachineInstr &MI) { - unsigned Opcode = MI.getOpcode(); - const TargetInstrDescriptor &Desc = II->get(Opcode); - - // Emit instruction prefixes if neccesary - if (Desc.TSFlags & X86II::OpSize) MCE.emitByte(0x66);// Operand size... - - switch (Desc.TSFlags & X86II::Op0Mask) { - case X86II::TB: - MCE.emitByte(0x0F); // Two-byte opcode prefix - break; - case X86II::D8: case X86II::D9: case X86II::DA: case X86II::DB: - case X86II::DC: case X86II::DD: case X86II::DE: case X86II::DF: - MCE.emitByte(0xD8+ - (((Desc.TSFlags & X86II::Op0Mask)-X86II::D8) - >> X86II::Op0Shift)); - break; // Two-byte opcode prefix - default: assert(0 && "Invalid prefix!"); - case 0: break; // No prefix! - } - - unsigned char BaseOpcode = II->getBaseOpcodeFor(Opcode); - switch (Desc.TSFlags & X86II::FormMask) { - default: assert(0 && "Unknown FormMask value in X86 MachineCodeEmitter!"); - case X86II::Pseudo: - if (Opcode != X86::IMPLICIT_USE) - std::cerr << "X86 Machine Code Emitter: No 'form', not emitting: " << MI; - break; - - case X86II::RawFrm: - MCE.emitByte(BaseOpcode); - if (MI.getNumOperands() == 1) { - MachineOperand &MO = MI.getOperand(0); - if (MO.isPCRelativeDisp()) { - // Conditional branch... FIXME: this should use an MBB destination! - emitPCRelativeBlockAddress(cast(MO.getVRegValue())); - } else if (MO.isGlobalAddress()) { - assert(MO.isPCRelative() && "Call target is not PC Relative?"); - emitGlobalAddressForCall(MO.getGlobal()); - } else if (MO.isExternalSymbol()) { - unsigned Address = MCE.getGlobalValueAddress(MO.getSymbolName()); - assert(Address && "Unknown external symbol!"); - emitMaybePCRelativeValue(Address, MO.isPCRelative()); - } else { - assert(0 && "Unknown RawFrm operand!"); - } - } - break; - - case X86II::AddRegFrm: - MCE.emitByte(BaseOpcode + getX86RegNum(MI.getOperand(0).getReg())); - if (MI.getNumOperands() == 2) { - MachineOperand &MO1 = MI.getOperand(1); - if (MO1.isImmediate() || MO1.getVRegValueOrNull() || - MO1.isGlobalAddress() || MO1.isExternalSymbol()) { - unsigned Size = sizeOfPtr(Desc); - if (Value *V = MO1.getVRegValueOrNull()) { - assert(Size == 4 && "Don't know how to emit non-pointer values!"); - emitGlobalAddressForPtr(cast(V)); - } else if (MO1.isGlobalAddress()) { - assert(Size == 4 && "Don't know how to emit non-pointer values!"); - assert(!MO1.isPCRelative() && "Function pointer ref is PC relative?"); - emitGlobalAddressForPtr(MO1.getGlobal()); - } else if (MO1.isExternalSymbol()) { - assert(Size == 4 && "Don't know how to emit non-pointer values!"); - - unsigned Address = MCE.getGlobalValueAddress(MO1.getSymbolName()); - assert(Address && "Unknown external symbol!"); - emitMaybePCRelativeValue(Address, MO1.isPCRelative()); - } else { - emitConstant(MO1.getImmedValue(), Size); - } - } - } - break; - - case X86II::MRMDestReg: { - MCE.emitByte(BaseOpcode); - MachineOperand &SrcOp = MI.getOperand(1+II->isTwoAddrInstr(Opcode)); - emitRegModRMByte(MI.getOperand(0).getReg(), getX86RegNum(SrcOp.getReg())); - if (MI.getNumOperands() == 4) - emitConstant(MI.getOperand(3).getImmedValue(), sizeOfPtr(Desc)); - break; - } - case X86II::MRMDestMem: - MCE.emitByte(BaseOpcode); - emitMemModRMByte(MI, 0, getX86RegNum(MI.getOperand(4).getReg())); - break; - - case X86II::MRMSrcReg: - MCE.emitByte(BaseOpcode); - emitRegModRMByte(MI.getOperand(MI.getNumOperands()-1).getReg(), - getX86RegNum(MI.getOperand(0).getReg())); - break; - - case X86II::MRMSrcMem: - MCE.emitByte(BaseOpcode); - emitMemModRMByte(MI, MI.getNumOperands()-4, - getX86RegNum(MI.getOperand(0).getReg())); - break; - - case X86II::MRMS0r: case X86II::MRMS1r: - case X86II::MRMS2r: case X86II::MRMS3r: - case X86II::MRMS4r: case X86II::MRMS5r: - case X86II::MRMS6r: case X86II::MRMS7r: - MCE.emitByte(BaseOpcode); - emitRegModRMByte(MI.getOperand(0).getReg(), - (Desc.TSFlags & X86II::FormMask)-X86II::MRMS0r); - - if (MI.getOperand(MI.getNumOperands()-1).isImmediate()) { - unsigned Size = sizeOfPtr(Desc); - emitConstant(MI.getOperand(MI.getNumOperands()-1).getImmedValue(), Size); - } - break; - - case X86II::MRMS0m: case X86II::MRMS1m: - case X86II::MRMS2m: case X86II::MRMS3m: - case X86II::MRMS4m: case X86II::MRMS5m: - case X86II::MRMS6m: case X86II::MRMS7m: - MCE.emitByte(BaseOpcode); - emitMemModRMByte(MI, 0, (Desc.TSFlags & X86II::FormMask)-X86II::MRMS0m); - - if (MI.getNumOperands() == 5) { - unsigned Size = sizeOfPtr(Desc); - emitConstant(MI.getOperand(4).getImmedValue(), Size); - } - break; - } -} diff --git a/lib/Target/X86/X86CodeEmitter.cpp b/lib/Target/X86/X86CodeEmitter.cpp index 07b1a0bcc3f..48885c96ee1 100644 --- a/lib/Target/X86/X86CodeEmitter.cpp +++ b/lib/Target/X86/X86CodeEmitter.cpp @@ -1,4 +1,4 @@ -//===-- X86/MachineCodeEmitter.cpp - Convert X86 code to machine code -----===// +//===-- X86/X86CodeEmitter.cpp - Convert X86 code to machine code ---------===// // // This file contains the pass that transforms the X86 machine instructions into // actual executable machine code.