path: root/include/llvm/MC/MCAssembler.h

//===- MCAssembler.h - Object File Generation -------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_MC_MCASSEMBLER_H
#define LLVM_MC_MCASSEMBLER_H

#include "llvm/MC/MCFixup.h"
#include "llvm/MC/MCInst.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/ilist.h"
#include "llvm/ADT/ilist_node.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/DataTypes.h"
#include <vector> // FIXME: Shouldn't be needed.

namespace llvm {
class raw_ostream;
class MCAsmLayout;
class MCAssembler;
class MCContext;
class MCCodeEmitter;
class MCExpr;
class MCFragment;
class MCObjectWriter;
class MCSection;
class MCSectionData;
class MCSymbol;
class MCSymbolData;
class MCValue;
class MCAsmBackend;

class MCFragment : public ilist_node<MCFragment> {
  friend class MCAsmLayout;

  MCFragment(const MCFragment&);     // DO NOT IMPLEMENT
  void operator=(const MCFragment&); // DO NOT IMPLEMENT

public:
  enum FragmentType {
    FT_Align,
    FT_Data,
    FT_Fill,
    FT_Inst,
    FT_Org,
    FT_Dwarf,
    FT_DwarfFrame,
    FT_LEB
  };

private:
  FragmentType Kind;

  /// Parent - The data for the section this fragment is in.
  MCSectionData *Parent;

  /// Atom - The atom this fragment is in, as represented by it's defining
  /// symbol. Atom's are only used by backends which set
  /// \see MCAsmBackend::hasReliableSymbolDifference().
  MCSymbolData *Atom;

  /// @name Assembler Backend Data
  /// @{
  //
  // FIXME: This could all be kept private to the assembler implementation.

  /// Offset - The offset of this fragment in its section. This is ~0 until
  /// initialized.
  uint64_t Offset;

  /// LayoutOrder - The layout order of this fragment.
  unsigned LayoutOrder;

  /// @}

protected:
  MCFragment(FragmentType _Kind, MCSectionData *_Parent = 0);

public:
  // Only for sentinel.
  MCFragment();
  virtual ~MCFragment();

  FragmentType getKind() const { return Kind; }

  MCSectionData *getParent() const { return Parent; }
  void setParent(MCSectionData *Value) { Parent = Value; }

  MCSymbolData *getAtom() const { return Atom; }
  void setAtom(MCSymbolData *Value) { Atom = Value; }

  unsigned getLayoutOrder() const { return LayoutOrder; }
  void setLayoutOrder(unsigned Value) { LayoutOrder = Value; }

  static bool classof(const MCFragment *O) { return true; }

  void dump();
};

class MCDataFragment : public MCFragment {
  virtual void anchor();
  SmallString<32> Contents;

  /// Fixups - The list of fixups in this fragment.
  std::vector<MCFixup> Fixups;

public:
  typedef std::vector<MCFixup>::const_iterator const_fixup_iterator;
  typedef std::vector<MCFixup>::iterator fixup_iterator;

public:
  MCDataFragment(MCSectionData *SD = 0) : MCFragment(FT_Data, SD) {}

  /// @name Accessors
  /// @{

  SmallString<32> &getContents() { return Contents; }
  const SmallString<32> &getContents() const { return Contents; }

  /// @}
  /// @name Fixup Access
  /// @{

  void addFixup(MCFixup Fixup) {
    // Enforce invariant that fixups are in offset order.
    assert((Fixups.empty() || Fixup.getOffset() >= Fixups.back().getOffset()) &&
           "Fixups must be added in order!");
    Fixups.push_back(Fixup);
  }

  std::vector<MCFixup> &getFixups() { return Fixups; }
  const std::vector<MCFixup> &getFixups() const { return Fixups; }

  fixup_iterator fixup_begin() { return Fixups.begin(); }
  const_fixup_iterator fixup_begin() const { return Fixups.begin(); }

  fixup_iterator fixup_end() {return Fixups.end();}
  const_fixup_iterator fixup_end() const {return Fixups.end();}

  size_t fixup_size() const { return Fixups.size(); }

  /// @}

  static bool classof(const MCFragment *F) {
    return F->getKind() == MCFragment::FT_Data;
  }
  static bool classof(const MCDataFragment *) { return true; }
};

// FIXME: This current incarnation of MCInstFragment doesn't make much sense, as
// it is almost entirely a duplicate of MCDataFragment. If we decide to stick
// with this approach (as opposed to making MCInstFragment a very light weight
// object with just the MCInst and a code size, then we should just change
// MCDataFragment to have an optional MCInst at its end.
class MCInstFragment : public MCFragment {
  virtual void anchor();

  /// Inst - The instruction this is a fragment for.
  MCInst Inst;

  /// Code - Binary data for the currently encoded instruction.