C++ SectionRef::isText方法代码示例

relocation_iterator RuntimeDyldMachO::processScatteredVANILLA(
                          unsigned SectionID, relocation_iterator RelI,
                          const ObjectFile &BaseObjT,
                          RuntimeDyldMachO::ObjSectionToIDMap &ObjSectionToID) {
  const MachOObjectFile &Obj =
    static_cast<const MachOObjectFile&>(BaseObjT);
  MachO::any_relocation_info RE =
    Obj.getRelocation(RelI->getRawDataRefImpl());

  SectionEntry &Section = Sections[SectionID];
  uint32_t RelocType = Obj.getAnyRelocationType(RE);
  bool IsPCRel = Obj.getAnyRelocationPCRel(RE);
  unsigned Size = Obj.getAnyRelocationLength(RE);
  uint64_t Offset = RelI->getOffset();
  uint8_t *LocalAddress = Section.getAddressWithOffset(Offset);
  unsigned NumBytes = 1 << Size;
  int64_t Addend = readBytesUnaligned(LocalAddress, NumBytes);

  unsigned SymbolBaseAddr = Obj.getScatteredRelocationValue(RE);
  section_iterator TargetSI = getSectionByAddress(Obj, SymbolBaseAddr);
  assert(TargetSI != Obj.section_end() && "Can't find section for symbol");
  uint64_t SectionBaseAddr = TargetSI->getAddress();
  SectionRef TargetSection = *TargetSI;
  bool IsCode = TargetSection.isText();
  uint32_t TargetSectionID =
    findOrEmitSection(Obj, TargetSection, IsCode, ObjSectionToID);

  Addend -= SectionBaseAddr;
  RelocationEntry R(SectionID, Offset, RelocType, Addend, IsPCRel, Size);

  addRelocationForSection(R, TargetSectionID);

  return ++RelI;
}

RelocationValueRef RuntimeDyldMachO::getRelocationValueRef(
    const ObjectFile &BaseTObj, const relocation_iterator &RI,
    const RelocationEntry &RE, ObjSectionToIDMap &ObjSectionToID) {

  const MachOObjectFile &Obj =
      static_cast<const MachOObjectFile &>(BaseTObj);
  MachO::any_relocation_info RelInfo =
      Obj.getRelocation(RI->getRawDataRefImpl());
  RelocationValueRef Value;

  bool IsExternal = Obj.getPlainRelocationExternal(RelInfo);
  if (IsExternal) {
    symbol_iterator Symbol = RI->getSymbol();
    StringRef TargetName;
    Symbol->getName(TargetName);
    SymbolTableMap::const_iterator SI =
      GlobalSymbolTable.find(TargetName.data());
    if (SI != GlobalSymbolTable.end()) {
      Value.SectionID = SI->second.first;
      Value.Offset = SI->second.second + RE.Addend;
    } else {
      Value.SymbolName = TargetName.data();
      Value.Offset = RE.Addend;
    }
  } else {
    SectionRef Sec = Obj.getRelocationSection(RelInfo);
    bool IsCode = Sec.isText();
    Value.SectionID = findOrEmitSection(Obj, Sec, IsCode, ObjSectionToID);
    uint64_t Addr = Sec.getAddress();
    Value.Offset = RE.Addend - Addr;
  }

  return Value;
}

RelocationValueRef RuntimeDyldMachO::getRelocationValueRef(
    const ObjectFile &BaseTObj, const relocation_iterator &RI,
    const RelocationEntry &RE, ObjSectionToIDMap &ObjSectionToID) {

  const MachOObjectFile &Obj =
      static_cast<const MachOObjectFile &>(BaseTObj);
  MachO::any_relocation_info RelInfo =
      Obj.getRelocation(RI->getRawDataRefImpl());
  RelocationValueRef Value;

  bool IsExternal = Obj.getPlainRelocationExternal(RelInfo);
  if (IsExternal) {
    symbol_iterator Symbol = RI->getSymbol();
    ErrorOr<StringRef> TargetNameOrErr = Symbol->getName();
    if (std::error_code EC = TargetNameOrErr.getError())
      report_fatal_error(EC.message());
    StringRef TargetName = *TargetNameOrErr;
    RTDyldSymbolTable::const_iterator SI =
      GlobalSymbolTable.find(TargetName.data());
    if (SI != GlobalSymbolTable.end()) {
      const auto &SymInfo = SI->second;
      Value.SectionID = SymInfo.getSectionID();
      Value.Offset = SymInfo.getOffset() + RE.Addend;
    } else {
      Value.SymbolName = TargetName.data();
      Value.Offset = RE.Addend;
    }
  } else {
    SectionRef Sec = Obj.getAnyRelocationSection(RelInfo);
    bool IsCode = Sec.isText();
    Value.SectionID = findOrEmitSection(Obj, Sec, IsCode, ObjSectionToID);
    uint64_t Addr = Sec.getAddress();
    Value.Offset = RE.Addend - Addr;
  }

  return Value;
}

void RuntimeDyldMachO::processRelocationRef(unsigned SectionID,
                                            RelocationRef RelI,
                                            ObjectImage &Obj,
                                            ObjSectionToIDMap &ObjSectionToID,
                                            const SymbolTableMap &Symbols,
                                            StubMap &Stubs) {
  const ObjectFile *OF = Obj.getObjectFile();
  const MachOObjectFile *MachO = static_cast<const MachOObjectFile*>(OF);
  MachO::any_relocation_info RE= MachO->getRelocation(RelI.getRawDataRefImpl());

  uint32_t RelType = MachO->getAnyRelocationType(RE);

  // FIXME: Properly handle scattered relocations.
  //        For now, optimistically skip these: they can often be ignored, as
  //        the static linker will already have applied the relocation, and it
  //        only needs to be reapplied if symbols move relative to one another.
  //        Note: This will fail horribly where the relocations *do* need to be
  //        applied, but that was already the case.
  if (MachO->isRelocationScattered(RE))
    return;

  RelocationValueRef Value;
  SectionEntry &Section = Sections[SectionID];

  bool isExtern = MachO->getPlainRelocationExternal(RE);
  bool IsPCRel = MachO->getAnyRelocationPCRel(RE);
  unsigned Size = MachO->getAnyRelocationLength(RE);
  uint64_t Offset;
  RelI.getOffset(Offset);
  uint8_t *LocalAddress = Section.Address + Offset;
  unsigned NumBytes = 1 << Size;
  uint64_t Addend = 0;
  memcpy(&Addend, LocalAddress, NumBytes);

  if (isExtern) {
    // Obtain the symbol name which is referenced in the relocation
    symbol_iterator Symbol = RelI.getSymbol();
    StringRef TargetName;
    Symbol->getName(TargetName);
    // First search for the symbol in the local symbol table
    SymbolTableMap::const_iterator lsi = Symbols.find(TargetName.data());
    if (lsi != Symbols.end()) {
      Value.SectionID = lsi->second.first;
      Value.Addend = lsi->second.second + Addend;
    } else {
      // Search for the symbol in the global symbol table
      SymbolTableMap::const_iterator gsi = GlobalSymbolTable.find(TargetName.data());
      if (gsi != GlobalSymbolTable.end()) {
        Value.SectionID = gsi->second.first;
        Value.Addend = gsi->second.second + Addend;
      } else {
        Value.SymbolName = TargetName.data();
        Value.Addend = Addend;
      }
    }
  } else {
    SectionRef Sec = MachO->getRelocationSection(RE);
    bool IsCode = false;
    Sec.isText(IsCode);
    Value.SectionID = findOrEmitSection(Obj, Sec, IsCode, ObjSectionToID);
    uint64_t Addr;
    Sec.getAddress(Addr);
    Value.Addend = Addend - Addr;
    if (IsPCRel)
      Value.Addend += Offset + NumBytes;
  }

  if (Arch == Triple::x86_64 && (RelType == MachO::X86_64_RELOC_GOT ||
                                 RelType == MachO::X86_64_RELOC_GOT_LOAD)) {
    assert(IsPCRel);
    assert(Size == 2);
    StubMap::const_iterator i = Stubs.find(Value);
    uint8_t *Addr;
    if (i != Stubs.end()) {
      Addr = Section.Address + i->second;
    } else {
      Stubs[Value] = Section.StubOffset;
      uint8_t *GOTEntry = Section.Address + Section.StubOffset;
      RelocationEntry RE(SectionID, Section.StubOffset,
                         MachO::X86_64_RELOC_UNSIGNED, 0, false, 3);
      if (Value.SymbolName)
        addRelocationForSymbol(RE, Value.SymbolName);
      else
        addRelocationForSection(RE, Value.SectionID);
      Section.StubOffset += 8;
      Addr = GOTEntry;
    }
    resolveRelocation(Section, Offset, (uint64_t)Addr,
                      MachO::X86_64_RELOC_UNSIGNED, Value.Addend, true, 2);
  } else if (Arch == Triple::arm &&
             (RelType & 0xf) == MachO::ARM_RELOC_BR24) {
    // This is an ARM branch relocation, need to use a stub function.

    //  Look up for existing stub.
    StubMap::const_iterator i = Stubs.find(Value);
    if (i != Stubs.end())
      resolveRelocation(Section, Offset,
                        (uint64_t)Section.Address + i->second,
                        RelType, 0, IsPCRel, Size);
    else {
//.........这里部分代码省略.........