blob: 999764fd3799eb3a268d193b412bb01daeae9cd8 [file] [log] [blame]
//===- ObjectLinker.h -----------------------------------------------------===//
//
// The MCLinker Project
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// ObjectLinker plays the same role as GNU collect2 to prepare all implicit
// parameters for FragmentLinker.
//
//===----------------------------------------------------------------------===//
#ifndef MCLD_OBJECT_OBJECT_LINKER_H
#define MCLD_OBJECT_OBJECT_LINKER_H
#ifdef ENABLE_UNITTEST
#include <gtest.h>
#endif
#include <stddef.h>
namespace mcld {
class Module;
class LinkerConfig;
class IRBuilder;
class FragmentLinker;
class TargetLDBackend;
class MemoryArea;
class MemoryAreaFactory;
class ObjectReader;
class DynObjReader;
class ArchiveReader;
class GroupReader;
class BinaryReader;
class ObjectWriter;
class DynObjWriter;
class ExecWriter;
class BinaryWriter;
/** \class ObjectLinker
* \brief ObjectLinker prepares parameters for FragmentLinker.
*/
class ObjectLinker
{
public:
ObjectLinker(const LinkerConfig& pConfig,
TargetLDBackend& pLDBackend);
~ObjectLinker();
void setup(Module& pModule, IRBuilder& pBuilder);
/// initFragmentLinker - initialize FragmentLinker
/// Connect all components in FragmentLinker
bool initFragmentLinker();
/// initStdSections - initialize standard sections of the output file.
bool initStdSections();
/// normalize - normalize the input files
void normalize();
/// linkable - check the linkability of current LinkerConfig
/// Check list:
/// - check the Attributes are not violate the constaint
/// - check every Input has a correct Attribute
bool linkable() const;
/// readRelocations - read all relocation entries
bool readRelocations();
/// mergeSections - put allinput sections into output sections
bool mergeSections();
/// allocateCommonSymobols - allocate fragments for common symbols to the
/// corresponding sections
bool allocateCommonSymbols();
/// addStandardSymbols - shared object and executable files need some
/// standard symbols
/// @return if there are some input symbols with the same name to the
/// standard symbols, return false
bool addStandardSymbols();
/// addTargetSymbols - some targets, such as MIPS and ARM, need some
/// target-dependent symbols
/// @return if there are some input symbols with the same name to the
/// target symbols, return false
bool addTargetSymbols();
/// addScriptSymbols - define symbols from the command line option or linker
/// scripts.
/// @return if there are some existing symbols with identical name to the
/// script symbols, return false.
bool addScriptSymbols();
/// scanRelocations - scan all relocation entries by output symbols.
bool scanRelocations();
/// initStubs - initialize stub-related stuff.
bool initStubs();
/// prelayout - help backend to do some modification before layout
bool prelayout();
/// layout - linearly layout all output sections and reserve some space
/// for GOT/PLT
/// Because we do not support instruction relaxing in this early version,
/// if there is a branch can not jump to its target, we return false
/// directly
bool layout();
/// postlayout - help backend to do some modification after layout
bool postlayout();
/// relocate - applying relocation entries and create relocation
/// section in the output files
/// Create relocation section, asking TargetLDBackend to
/// read the relocation information into RelocationEntry
/// and push_back into the relocation section
bool relocation();
/// finalizeSymbolValue - finalize the symbol value
bool finalizeSymbolValue();
/// emitOutput - emit the output file.
bool emitOutput(MemoryArea& pOutput);
/// postProcessing - do modificatiion after all processes
bool postProcessing(MemoryArea& pOutput);
/// getLinker - get internal FragmentLinker object
const FragmentLinker* getLinker() const { return m_pLinker; }
FragmentLinker* getLinker() { return m_pLinker; }
/// hasInitLinker - has Linker been initialized?
bool hasInitLinker() const
{ return (NULL != m_pLinker); }
// ----- readers and writers ----- //
const ObjectReader* getObjectReader () const { return m_pObjectReader; }
ObjectReader* getObjectReader () { return m_pObjectReader; }
const DynObjReader* getDynObjReader () const { return m_pDynObjReader; }
DynObjReader* getDynObjReader () { return m_pDynObjReader; }
const ArchiveReader* getArchiveReader() const { return m_pArchiveReader; }
ArchiveReader* getArchiveReader() { return m_pArchiveReader; }
const GroupReader* getGroupReader () const { return m_pGroupReader; }
GroupReader* getGroupReader () { return m_pGroupReader; }
const BinaryReader* getBinaryReader () const { return m_pBinaryReader; }
BinaryReader* getBinaryReader () { return m_pBinaryReader; }
const ObjectWriter* getWriter () const { return m_pWriter; }
ObjectWriter* getWriter () { return m_pWriter; }
private:
const LinkerConfig& m_Config;
FragmentLinker* m_pLinker;
Module* m_pModule;
IRBuilder* m_pBuilder;
TargetLDBackend &m_LDBackend;
// ----- readers and writers ----- //
ObjectReader* m_pObjectReader;
DynObjReader* m_pDynObjReader;
ArchiveReader* m_pArchiveReader;
GroupReader* m_pGroupReader;
BinaryReader* m_pBinaryReader;
ObjectWriter* m_pWriter;
};
} // end namespace mcld
#endif