path: root/lib/Target/X86/X86CodeEmitter.cpp

//===-- X86/X86CodeEmitter.cpp - Convert X86 code to machine code ---------===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the pass that transforms the X86 machine instructions into
// relocatable machine code.
//
//===----------------------------------------------------------------------===//

#define DEBUG_TYPE "x86-emitter"
#include "X86InstrInfo.h"
#include "X86JITInfo.h"
#include "X86Subtarget.h"
#include "X86TargetMachine.h"
#include "X86Relocations.h"
#include "X86.h"
#include "llvm/LLVMContext.h"
#include "llvm/PassManager.h"
#include "llvm/CodeGen/JITCodeEmitter.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/Function.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/MC/MCCodeEmitter.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCInst.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetOptions.h"
using namespace llvm;

STATISTIC(NumEmitted, "Number of machine instructions emitted");

namespace {
  template<class CodeEmitter>
  class Emitter : public MachineFunctionPass {
    const X86InstrInfo  *II;
    const TargetData    *TD;
    X86TargetMachine    &TM;
    CodeEmitter         &MCE;
    MachineModuleInfo   *MMI;
    intptr_t PICBaseOffset;
    bool Is64BitMode;
    bool IsPIC;
  public:
    static char ID;
    explicit Emitter(X86TargetMachine &tm, CodeEmitter &mce)
      : MachineFunctionPass(ID), II(0), TD(0), TM(tm), 
      MCE(mce), PICBaseOffset(0), Is64BitMode(false),
      IsPIC(TM.getRelocationModel() == Reloc::PIC_) {}
    Emitter(X86TargetMachine &tm, CodeEmitter &mce,
            const X86InstrInfo &ii, const TargetData &td, bool is64)
      : MachineFunctionPass(ID), II(&ii), TD(&td), TM(tm), 
      MCE(mce), PICBaseOffset(0), Is64BitMode(is64),
      IsPIC(TM.getRelocationModel() == Reloc::PIC_) {}

    bool runOnMachineFunction(MachineFunction &MF);

    virtual const char *getPassName() const {
      return "X86 Machine Code Emitter";
    }

    void emitInstruction(MachineInstr &MI, const MCInstrDesc *Desc);
    
    void getAnalysisUsage(AnalysisUsage &AU) const {
      AU.setPreservesAll();
      AU.addRequired<MachineModuleInfo>();
      MachineFunctionPass::getAnalysisUsage(AU);
    }

  private:
    void emitPCRelativeBlockAddress(MachineBasicBlock *MBB);
    void emitGlobalAddress(const GlobalValue *GV, unsigned Reloc,
                           intptr_t Disp = 0, intptr_t PCAdj = 0,
                           bool Indirect = false);
    void emitExternalSymbolAddress(const char *ES, unsigned Reloc);
    void emitConstPoolAddress(unsigned CPI, unsigned Reloc, intptr_t Disp = 0,
                              intptr_t PCAdj = 0);
    void emitJumpTableAddress(unsigned JTI, unsigned Reloc,
                              intptr_t PCAdj = 0);

    void emitDisplacementField(const MachineOperand *RelocOp, int DispVal,
                               intptr_t Adj = 0, bool IsPCRel = true);

    void emitRegModRMByte(unsigned ModRMReg, unsigned RegOpcodeField);
    void emitRegModRMByte(unsigned RegOpcodeField);
    void emitSIBByte(unsigned SS, unsigned Index, unsigned Base);
    void emitConstant(uint64_t Val, unsigned Size);

    void emitMemModRMByte(const MachineInstr &MI,
                          unsigned Op, unsigned RegOpcodeField,
                          intptr_t PCAdj = 0);
  };

template<class CodeEmitter>
  char Emitter<CodeEmitter>::ID = 0;
} // end anonymous namespace.

/// createX86CodeEmitterPass - Return a pass that emits the collected X86 code
/// to the specified templated MachineCodeEmitter object.
FunctionPass *llvm::createX86JITCodeEmitterPass(X86TargetMachine &TM,
                                                JITCodeEmitter &JCE) {
  return new Emitter<JITCodeEmitter>(TM, <