path: root/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp

//===-- RuntimeDyldELF.cpp - Run-time dynamic linker for MC-JIT -*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Implementation of ELF support for the MC-JIT runtime dynamic linker.
//
//===----------------------------------------------------------------------===//

#define DEBUG_TYPE "dyld"
#include "RuntimeDyldELF.h"
#include "JITRegistrar.h"
#include "ObjectImageCommon.h"
#include "llvm/ADT/IntervalMap.h"
#include "llvm/ADT/OwningPtr.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Triple.h"
#include "llvm/ExecutionEngine/ObjectBuffer.h"
#include "llvm/ExecutionEngine/ObjectImage.h"
#include "llvm/Object/ELF.h"
#include "llvm/Object/ObjectFile.h"
#include "llvm/Support/ELF.h"
using namespace llvm;
using namespace llvm::object;

namespace {

static inline
error_code check(error_code Err) {
  if (Err) {
    report_fatal_error(Err.message());
  }
  return Err;
}

template<class ELFT>
class DyldELFObject
  : public ELFObjectFile<ELFT> {
  LLVM_ELF_IMPORT_TYPES_ELFT(ELFT)

  typedef Elf_Shdr_Impl<ELFT> Elf_Shdr;
  typedef Elf_Sym_Impl<ELFT> Elf_Sym;
  typedef
    Elf_Rel_Impl<ELFT, false> Elf_Rel;
  typedef
    Elf_Rel_Impl<ELFT, true> Elf_Rela;

  typedef Elf_Ehdr_Impl<ELFT> Elf_Ehdr;

  typedef typename ELFDataTypeTypedefHelper<
          ELFT>::value_type addr_type;

public:
  DyldELFObject(MemoryBuffer *Wrapper, error_code &ec);

  void updateSectionAddress(const SectionRef &Sec, uint64_t Addr);
  void updateSymbolAddress(const SymbolRef &Sym, uint64_t Addr);

  // Methods for type inquiry through isa, cast and dyn_cast
  static inline bool classof(const Binary *v) {
    return (isa<ELFObjectFile<ELFT> >(v)
            && classof(cast<ELFObjectFile
                <ELFT> >(v)));
  }
  static inline bool classof(
      const ELFObjectFile<ELFT> *v) {
    return v->isDyldType();
  }
};

template<class ELFT>
class ELFObjectImage : public ObjectImageCommon {
  protected:
    DyldELFObject<ELFT> *DyldObj;
    bool Registered;

  public:
    ELFObjectImage(ObjectBuffer *Input,
                 DyldELFObject<ELFT> *Obj)
    : ObjectImageCommon(Input, Obj),
      DyldObj(Obj),
      Registered(false) {}

    virtual ~ELFObjectImage() {
      if (Registered)
        deregisterWithDebugger();
    }

    // Subclasses can override these methods to update the image with loaded
    // addresses for sections and common symbols
    virtual void updateSectionAddress(const SectionRef &Sec, uint64_t Addr)
    {
      DyldObj->updateSectionAddress(Sec, Addr);
    }

    virtual void updateSymbolAddress(const SymbolRef &Sym, uint64_t Addr)
    {
      DyldObj->updateSymbolAddress(Sym, Addr);
    }

    virtual void registerWithDebugger()
    {
      JITRegistrar::getGDBRegistrar().registerObject(*Buffer);
      Registered = true;
    }
    virtual void deregisterWithDebugger()
    {
      JITRegistrar::getGDBRegistrar().deregisterObject(*Buffer);
    }
};

// The MemoryBuffer passed into this constructor is just a wrapper around the
// actual memory.  Ultimately, the Binary parent class will take ownership of
// this MemoryBuffer object but not the underlying memory.
template<class ELFT>
DyldELFObject<ELFT>::DyldELFObject(MemoryBuffer *Wrapper, error_code &ec)
  : ELFObjectFile<ELFT>(Wrapper, ec) {
  this->isDyldELFObject = true;
}

template<class ELFT>
void DyldELFObject<ELFT>::updateSectionAddress(const SectionRef &Sec,
                                               uint64_t Addr) {
  DataRefImpl ShdrRef = Sec.getRawDataRefImpl();
  <