Index: ELF/DynamicLibraryWriter.h =================================================================== --- ELF/DynamicLibraryWriter.h +++ ELF/DynamicLibraryWriter.h @@ -9,15 +9,7 @@ #ifndef LLD_READER_WRITER_ELF_DYNAMIC_LIBRARY_WRITER_H #define LLD_READER_WRITER_ELF_DYNAMIC_LIBRARY_WRITER_H -#include "lld/ReaderWriter/Writer.h" - -#include "DefaultLayout.h" -#include "TargetLayout.h" -#include "ExecutableAtoms.h" - -#include "lld/ReaderWriter/ELFTargetInfo.h" - -#include "llvm/ADT/StringSet.h" +#include "OutputELFWriter.h" namespace lld { namespace elf { @@ -31,326 +23,53 @@ // DynamicLibraryWriter Class //===----------------------------------------------------------------------===// template -class DynamicLibraryWriter : public ELFWriter { +class DynamicLibraryWriter : public OutputELFWriter { public: - typedef Elf_Shdr_Impl Elf_Shdr; - typedef Elf_Sym_Impl Elf_Sym; - typedef Elf_Dyn_Impl Elf_Dyn; - - DynamicLibraryWriter(const ELFTargetInfo &ti); + DynamicLibraryWriter(const ELFTargetInfo &ti):OutputELFWriter(ti) + {} private: - // build the sections that need to be created - void buildChunks(const File &file); - virtual error_code writeFile(const File &File, StringRef path); - void buildAtomToAddressMap(); - void buildStaticSymbolTable(const File &file); void buildDynamicSymbolTable(const File &file); - void buildSectionHeaderTable(); - void assignSectionsWithNoSegments(); void addDefaultAtoms(); void addFiles(InputFiles&); void finalizeDefaultAtomValues(); - uint64_t addressOfAtom(const Atom *atom) { - return _atomToAddressMap[atom]; - } - - void createDefaultSections(); - - void createDefaultDynamicEntries() {} - llvm::BumpPtrAllocator _alloc; - - const ELFTargetInfo &_targetInfo; - TargetHandler &_targetHandler; - - typedef llvm::DenseMap AtomToAddress; - AtomToAddress _atomToAddressMap; - TargetLayout *_layout; - LLD_UNIQUE_BUMP_PTR(Header) _Header; - LLD_UNIQUE_BUMP_PTR(ProgramHeader) _programHeader; - LLD_UNIQUE_BUMP_PTR(SymbolTable) _symtab; - LLD_UNIQUE_BUMP_PTR(StringTable) _strtab; - LLD_UNIQUE_BUMP_PTR(StringTable) _shstrtab; - LLD_UNIQUE_BUMP_PTR(SectionHeader) _shdrtab; - /// \name Dynamic sections. - /// @{ - LLD_UNIQUE_BUMP_PTR(DynamicTable) _dynamicTable; - LLD_UNIQUE_BUMP_PTR(DynamicSymbolTable) _dynamicSymbolTable; - LLD_UNIQUE_BUMP_PTR(StringTable) _dynamicStringTable; - LLD_UNIQUE_BUMP_PTR(InterpSection) _interpSection; - LLD_UNIQUE_BUMP_PTR(HashSection) _hashTable; - llvm::StringSet<> _soNeeded; - /// @} - CRuntimeFile _runtimeFile; }; //===----------------------------------------------------------------------===// // DynamicLibraryWriter //===----------------------------------------------------------------------===// template -DynamicLibraryWriter::DynamicLibraryWriter(const ELFTargetInfo &ti) - : _targetInfo(ti), _targetHandler(ti.getTargetHandler()), - _runtimeFile(ti) { - _layout = &_targetHandler.targetLayout(); -} - -template -void DynamicLibraryWriter::buildChunks(const File &file) { - for (const DefinedAtom *definedAtom : file.defined()) { - _layout->addAtom(definedAtom); - } - for (const AbsoluteAtom *absoluteAtom : file.absolute()) - _layout->addAtom(absoluteAtom); -} - -template -void DynamicLibraryWriter::buildStaticSymbolTable(const File &file) { - for (auto sec : _layout->sections()) - if (auto section = dyn_cast>(sec)) - for (const auto &atom : section->atoms()) - _symtab->addSymbol(atom->_atom, section->ordinal(), atom->_virtualAddr); - for (auto &atom : _layout->absoluteAtoms()) - _symtab->addSymbol(atom->_atom, ELF::SHN_ABS, atom->_virtualAddr); - for (const UndefinedAtom *a : file.undefined()) - _symtab->addSymbol(a, ELF::SHN_UNDEF); -} - -template void DynamicLibraryWriter::buildDynamicSymbolTable(const File &file) { - for (const auto sla : file.sharedLibrary()) { - _dynamicSymbolTable->addSymbol(sla, ELF::SHN_UNDEF); - _soNeeded.insert(sla->loadName()); - } // Add all the defined symbols to the dynamic symbol table // we need hooks into the Atom to find out which atoms need // to be exported - for (auto sec : _layout->sections()) + for (auto sec : this->_layout->sections()) if (auto section = dyn_cast>(sec)) for (const auto &atom : section->atoms()) { const DefinedAtom *da = dyn_cast(atom->_atom); if (da && (da->scope() != DefinedAtom::scopeTranslationUnit)) - _dynamicSymbolTable->addSymbol(atom->_atom, section->ordinal(), - atom->_virtualAddr, atom); + this->_dynamicSymbolTable->addSymbol(atom->_atom, section->ordinal(), + atom->_virtualAddr, atom); } - for (const auto &loadName : _soNeeded) { - Elf_Dyn dyn; - dyn.d_tag = DT_NEEDED; - dyn.d_un.d_val = _dynamicStringTable->addString(loadName.getKey()); - _dynamicTable->addEntry(dyn); - } -} -template void DynamicLibraryWriter::buildAtomToAddressMap() { - for (auto sec : _layout->sections()) - if (auto section = dyn_cast>(sec)) - for (const auto &atom : section->atoms()) - _atomToAddressMap[atom->_atom] = atom->_virtualAddr; - // build the atomToAddressMap that contains absolute symbols too - for (auto &atom : _layout->absoluteAtoms()) - _atomToAddressMap[atom->_atom] = atom->_virtualAddr; + OutputELFWriter::buildDynamicSymbolTable(file); } template -void DynamicLibraryWriter::buildSectionHeaderTable() { - for (auto mergedSec : _layout->mergedSections()) { - if (mergedSec->kind() != Chunk::K_ELFSection && - mergedSec->kind() != Chunk::K_AtomSection) - continue; - if (mergedSec->hasSegment()) - _shdrtab->appendSection(mergedSec); - } -} - -template -void DynamicLibraryWriter::assignSectionsWithNoSegments() { - for (auto mergedSec : _layout->mergedSections()) { - if (mergedSec->kind() != Chunk::K_ELFSection && - mergedSec->kind() != Chunk::K_AtomSection) - continue; - if (!mergedSec->hasSegment()) - _shdrtab->appendSection(mergedSec); - } - _layout->assignOffsetsForMiscSections(); - for (auto sec : _layout->sections()) - if (auto section = dyn_cast>(sec)) - if (!DefaultLayout::hasOutputSegment(section)) - _shdrtab->updateSection(section); -} - -/// \brief Add absolute symbols by default. These are linker added -/// absolute symbols -template -void DynamicLibraryWriter::addDefaultAtoms() { - _runtimeFile.addAbsoluteAtom("__bss_start"); -} +void DynamicLibraryWriter::addDefaultAtoms() { } -/// \brief Hook in lld to add CRuntime file template void DynamicLibraryWriter::addFiles(InputFiles &inputFiles) { - addDefaultAtoms(); - inputFiles.prependFile(_runtimeFile); - // Give a chance for the target to add atoms - _targetHandler.addFiles(inputFiles); + this->_targetHandler.addFiles(inputFiles); } -/// Finalize the value of all the absolute symbols that we -/// created template void DynamicLibraryWriter::finalizeDefaultAtomValues() { - auto bssStartAtomIter = _layout->findAbsoluteAtom("__bss_start"); - - assert(!(bssStartAtomIter == _layout->absoluteAtoms().end()) && - "Unable to find the absolute atoms that have been added by lld"); - - auto phe = _programHeader->findProgramHeader( - llvm::ELF::PT_LOAD, llvm::ELF::PF_W, llvm::ELF::PF_X); - - (*bssStartAtomIter)->_virtualAddr = (*phe)->p_vaddr + (*phe)->p_filesz; - - // Give a chance for the target to finalize its atom values - _targetHandler.finalizeSymbolValues(); -} - -template -error_code DynamicLibraryWriter::writeFile(const File &file, StringRef path) { - buildChunks(file); - - // Call the preFlight callbacks to modify the sections and the atoms - // contained in them, in anyway the targets may want - _layout->doPreFlight(); - - // Create the default sections like the symbol table, string table, and the - // section string table - createDefaultSections(); - - _dynamicTable->createDefaultEntries(); - buildDynamicSymbolTable(file); - - // Set the Layout - _layout->assignSectionsToSegments(); - _layout->assignFileOffsets(); - _layout->assignVirtualAddress(); - - // Finalize the default value of symbols that the linker adds - finalizeDefaultAtomValues(); - - // Build the Atom To Address map for applying relocations - buildAtomToAddressMap(); - - // Create symbol table and section string table - buildStaticSymbolTable(file); - - // Finalize the layout by calling the finalize() functions - _layout->finalize(); - - // build Section Header table - buildSectionHeaderTable(); - - // assign Offsets and virtual addresses - // for sections with no segments - assignSectionsWithNoSegments(); - - _dynamicTable->updateDynamicTable(_hashTable.get(), - _dynamicSymbolTable.get()); - - uint64_t totalSize = _shdrtab->fileOffset() + _shdrtab->fileSize(); - - OwningPtr buffer; - error_code ec = FileOutputBuffer::create(path, - totalSize, buffer, - FileOutputBuffer::F_executable); - if (ec) - return ec; - - _Header->e_ident(ELF::EI_CLASS, _targetInfo.is64Bits() ? ELF::ELFCLASS64 : - ELF::ELFCLASS32); - _Header->e_ident(ELF::EI_DATA, _targetInfo.isLittleEndian() ? - ELF::ELFDATA2LSB : ELF::ELFDATA2MSB); - _Header->e_type(_targetInfo.getOutputType()); - _Header->e_machine(_targetInfo.getOutputMachine()); - - if (!_targetHandler.doesOverrideHeader()) { - _Header->e_ident(ELF::EI_VERSION, 1); - _Header->e_ident(ELF::EI_OSABI, 0); - _Header->e_version(1); - } else { - // override the contents of the ELF Header - _targetHandler.setHeaderInfo(_Header.get()); - } - _Header->e_phoff(_programHeader->fileOffset()); - _Header->e_shoff(_shdrtab->fileOffset()); - _Header->e_phentsize(_programHeader->entsize()); - _Header->e_phnum(_programHeader->numHeaders()); - _Header->e_shentsize(_shdrtab->entsize()); - _Header->e_shnum(_shdrtab->numHeaders()); - _Header->e_shstrndx(_shstrtab->ordinal()); - uint64_t virtualAddr = 0; - _layout->findAtomAddrByName(_targetInfo.getEntry(), virtualAddr); - - // HACK: We have to write out the header and program header here even though - // they are a member of a segment because only sections are written in the - // following loop. - _Header->write(this, *buffer); - _programHeader->write(this, *buffer); - - for (auto section : _layout->sections()) - section->write(this, *buffer); - - return buffer->commit(); + this->_targetHandler.finalizeSymbolValues(); } -template -void DynamicLibraryWriter::createDefaultSections() { - _Header.reset(new (_alloc) Header(_targetInfo)); - _programHeader.reset(new (_alloc) ProgramHeader(_targetInfo)); - _layout->setHeader(_Header.get()); - _layout->setProgramHeader(_programHeader.get()); - - _symtab.reset(new (_alloc) SymbolTable( - _targetInfo, ".symtab", DefaultLayout::ORDER_SYMBOL_TABLE)); - _strtab.reset(new (_alloc) StringTable( - _targetInfo, ".strtab", DefaultLayout::ORDER_STRING_TABLE)); - _shstrtab.reset(new (_alloc) StringTable( - _targetInfo, ".shstrtab", DefaultLayout::ORDER_SECTION_STRINGS)); - _shdrtab.reset(new (_alloc) SectionHeader( - _targetInfo, DefaultLayout::ORDER_SECTION_HEADERS)); - _layout->addSection(_symtab.get()); - _layout->addSection(_strtab.get()); - _layout->addSection(_shstrtab.get()); - _shdrtab->setStringSection(_shstrtab.get()); - _symtab->setStringSection(_strtab.get()); - _layout->addSection(_shdrtab.get()); - - _dynamicTable.reset(new (_alloc) DynamicTable( - _targetInfo, ".dynamic", DefaultLayout::ORDER_DYNAMIC)); - _dynamicStringTable.reset(new (_alloc) StringTable( - _targetInfo, ".dynstr", DefaultLayout::ORDER_DYNAMIC_STRINGS, - true)); - _dynamicSymbolTable.reset(new (_alloc) DynamicSymbolTable( - _targetInfo, ".dynsym", DefaultLayout::ORDER_DYNAMIC_SYMBOLS)); - _interpSection.reset(new (_alloc) InterpSection( - _targetInfo, ".interp", DefaultLayout::ORDER_INTERP, - _targetInfo.getInterpreter())); - _hashTable.reset(new (_alloc) HashSection( - _targetInfo, ".hash", DefaultLayout::ORDER_HASH)); - _layout->addSection(_dynamicTable.get()); - _layout->addSection(_dynamicStringTable.get()); - _layout->addSection(_dynamicSymbolTable.get()); - _layout->addSection(_interpSection.get()); - _layout->addSection(_hashTable.get()); - _dynamicSymbolTable->setStringSection(_dynamicStringTable.get()); - if (_layout->hasDynamicRelocationTable()) - _layout->getDynamicRelocationTable()->setSymbolTable( - _dynamicSymbolTable.get()); - if (_layout->hasPLTRelocationTable()) - _layout->getPLTRelocationTable()->setSymbolTable( - _dynamicSymbolTable.get()); - - // give a chance for the target to add sections - _targetHandler.createDefaultSections(); -} } // namespace elf } // namespace lld Index: ELF/ExecutableWriter.h =================================================================== --- ELF/ExecutableWriter.h +++ ELF/ExecutableWriter.h @@ -9,15 +9,7 @@ #ifndef LLD_READER_WRITER_ELF_EXECUTABLE_WRITER_H #define LLD_READER_WRITER_ELF_EXECUTABLE_WRITER_H -#include "lld/ReaderWriter/Writer.h" - -#include "DefaultLayout.h" -#include "TargetLayout.h" -#include "ExecutableAtoms.h" - -#include "lld/ReaderWriter/ELFTargetInfo.h" - -#include "llvm/ADT/StringSet.h" +#include "OutputELFWriter.h" namespace lld { namespace elf { @@ -31,148 +23,29 @@ // ExecutableWriter Class //===----------------------------------------------------------------------===// template -class ExecutableWriter : public ELFWriter { +class ExecutableWriter : public OutputELFWriter { public: - typedef Elf_Shdr_Impl Elf_Shdr; - typedef Elf_Sym_Impl Elf_Sym; - typedef Elf_Dyn_Impl Elf_Dyn; - - ExecutableWriter(const ELFTargetInfo &ti); + ExecutableWriter(const ELFTargetInfo &ti) + : OutputELFWriter(ti), _runtimeFile(ti) + {} private: - // build the sections that need to be created - void buildChunks(const File &file); - virtual error_code writeFile(const File &File, StringRef path); - void buildAtomToAddressMap(); - void buildStaticSymbolTable(const File &file); - void buildDynamicSymbolTable(const File &file); - void buildSectionHeaderTable(); - void assignSectionsWithNoSegments(); - void addDefaultAtoms(); - void addFiles(InputFiles&); - void finalizeDefaultAtomValues(); - - uint64_t addressOfAtom(const Atom *atom) { - return _atomToAddressMap[atom]; - } - - void createDefaultSections(); - - void createDefaultDynamicEntries() {} - - llvm::BumpPtrAllocator _alloc; - - const ELFTargetInfo &_targetInfo; - TargetHandler &_targetHandler; - - typedef llvm::DenseMap AtomToAddress; - AtomToAddress _atomToAddressMap; - TargetLayout *_layout; - LLD_UNIQUE_BUMP_PTR(Header) _Header; - LLD_UNIQUE_BUMP_PTR(ProgramHeader) _programHeader; - LLD_UNIQUE_BUMP_PTR(SymbolTable) _symtab; - LLD_UNIQUE_BUMP_PTR(StringTable) _strtab; - LLD_UNIQUE_BUMP_PTR(StringTable) _shstrtab; - LLD_UNIQUE_BUMP_PTR(SectionHeader) _shdrtab; - /// \name Dynamic sections. - /// @{ - LLD_UNIQUE_BUMP_PTR(DynamicTable) _dynamicTable; - LLD_UNIQUE_BUMP_PTR(DynamicSymbolTable) _dynamicSymbolTable; - LLD_UNIQUE_BUMP_PTR(StringTable) _dynamicStringTable; - LLD_UNIQUE_BUMP_PTR(InterpSection) _interpSection; - LLD_UNIQUE_BUMP_PTR(HashSection) _hashTable; - llvm::StringSet<> _soNeeded; - /// @} + virtual void addDefaultAtoms(); + virtual void addFiles(InputFiles&); + virtual void finalizeDefaultAtomValues(); + CRuntimeFile _runtimeFile; }; //===----------------------------------------------------------------------===// // ExecutableWriter //===----------------------------------------------------------------------===// -template -ExecutableWriter::ExecutableWriter(const ELFTargetInfo &ti) - : _targetInfo(ti), _targetHandler(ti.getTargetHandler()), - _runtimeFile(ti) { - _layout = &_targetHandler.targetLayout(); -} - -template -void ExecutableWriter::buildChunks(const File &file) { - for (const DefinedAtom *definedAtom : file.defined()) { - _layout->addAtom(definedAtom); - } - for (const AbsoluteAtom *absoluteAtom : file.absolute()) - _layout->addAtom(absoluteAtom); -} - -template -void ExecutableWriter::buildStaticSymbolTable(const File &file) { - for (auto sec : _layout->sections()) - if (auto section = dyn_cast>(sec)) - for (const auto &atom : section->atoms()) - _symtab->addSymbol(atom->_atom, section->ordinal(), atom->_virtualAddr); - for (auto &atom : _layout->absoluteAtoms()) - _symtab->addSymbol(atom->_atom, ELF::SHN_ABS, atom->_virtualAddr); - for (const UndefinedAtom *a : file.undefined()) - _symtab->addSymbol(a, ELF::SHN_UNDEF); -} - -template -void ExecutableWriter::buildDynamicSymbolTable(const File &file) { - for (const auto sla : file.sharedLibrary()) { - _dynamicSymbolTable->addSymbol(sla, ELF::SHN_UNDEF); - _soNeeded.insert(sla->loadName()); - } - for (const auto &loadName : _soNeeded) { - Elf_Dyn dyn; - dyn.d_tag = DT_NEEDED; - dyn.d_un.d_val = _dynamicStringTable->addString(loadName.getKey()); - _dynamicTable->addEntry(dyn); - } -} - -template void ExecutableWriter::buildAtomToAddressMap() { - for (auto sec : _layout->sections()) - if (auto section = dyn_cast>(sec)) - for (const auto &atom : section->atoms()) - _atomToAddressMap[atom->_atom] = atom->_virtualAddr; - // build the atomToAddressMap that contains absolute symbols too - for (auto &atom : _layout->absoluteAtoms()) - _atomToAddressMap[atom->_atom] = atom->_virtualAddr; -} - -template -void ExecutableWriter::buildSectionHeaderTable() { - for (auto mergedSec : _layout->mergedSections()) { - if (mergedSec->kind() != Chunk::K_ELFSection && - mergedSec->kind() != Chunk::K_AtomSection) - continue; - if (mergedSec->hasSegment()) - _shdrtab->appendSection(mergedSec); - } -} - -template -void ExecutableWriter::assignSectionsWithNoSegments() { - for (auto mergedSec : _layout->mergedSections()) { - if (mergedSec->kind() != Chunk::K_ELFSection && - mergedSec->kind() != Chunk::K_AtomSection) - continue; - if (!mergedSec->hasSegment()) - _shdrtab->appendSection(mergedSec); - } - _layout->assignOffsetsForMiscSections(); - for (auto sec : _layout->sections()) - if (auto section = dyn_cast>(sec)) - if (!DefaultLayout::hasOutputSegment(section)) - _shdrtab->updateSection(section); -} /// \brief Add absolute symbols by default. These are linker added /// absolute symbols template void ExecutableWriter::addDefaultAtoms() { - _runtimeFile.addUndefinedAtom(_targetInfo.getEntry()); + _runtimeFile.addUndefinedAtom(this->_targetInfo.getEntry()); _runtimeFile.addAbsoluteAtom("__bss_start"); _runtimeFile.addAbsoluteAtom("__bss_end"); _runtimeFile.addAbsoluteAtom("_end"); @@ -193,17 +66,17 @@ addDefaultAtoms(); inputFiles.prependFile(_runtimeFile); // Give a chance for the target to add atoms - _targetHandler.addFiles(inputFiles); + this->_targetHandler.addFiles(inputFiles); } /// Finalize the value of all the absolute symbols that we /// created template void ExecutableWriter::finalizeDefaultAtomValues() { - auto bssStartAtomIter = _layout->findAbsoluteAtom("__bss_start"); - auto bssEndAtomIter = _layout->findAbsoluteAtom("__bss_end"); - auto underScoreEndAtomIter = _layout->findAbsoluteAtom("_end"); - auto endAtomIter = _layout->findAbsoluteAtom("end"); + auto bssStartAtomIter = this->_layout->findAbsoluteAtom("__bss_start"); + auto bssEndAtomIter = this->_layout->findAbsoluteAtom("__bss_end"); + auto underScoreEndAtomIter = this->_layout->findAbsoluteAtom("_end"); + auto endAtomIter = this->_layout->findAbsoluteAtom("end"); auto startEnd = [&](StringRef sym, StringRef sec) -> void { // TODO: This looks like a good place to use Twine... @@ -212,9 +85,9 @@ start += "_start"; end += sym; end += "_end"; - auto s = _layout->findAbsoluteAtom(start); - auto e = _layout->findAbsoluteAtom(end); - auto section = _layout->findOutputSection(sec); + auto s = this->_layout->findAbsoluteAtom(start); + auto e = this->_layout->findAbsoluteAtom(end); + auto section = this->_layout->findOutputSection(sec); if (section) { (*s)->_virtualAddr = section->virtualAddr(); (*e)->_virtualAddr = section->virtualAddr() + section->memSize(); @@ -229,16 +102,16 @@ startEnd("rela_iplt", ".rela.plt"); startEnd("fini_array", ".fini_array"); - assert(!(bssStartAtomIter == _layout->absoluteAtoms().end() || - bssEndAtomIter == _layout->absoluteAtoms().end() || - underScoreEndAtomIter == _layout->absoluteAtoms().end() || - endAtomIter == _layout->absoluteAtoms().end()) && + assert(!(bssStartAtomIter == this->_layout->absoluteAtoms().end() || + bssEndAtomIter == this->_layout->absoluteAtoms().end() || + underScoreEndAtomIter == this->_layout->absoluteAtoms().end() || + endAtomIter == this->_layout->absoluteAtoms().end()) && "Unable to find the absolute atoms that have been added by lld"); - auto phe = _programHeader->findProgramHeader( + auto phe = this->_programHeader->findProgramHeader( llvm::ELF::PT_LOAD, llvm::ELF::PF_W, llvm::ELF::PF_X); - assert(!(phe == _programHeader->end()) && + assert(!(phe == this->_programHeader->end()) && "Can't find a data segment in the program header!"); (*bssStartAtomIter)->_virtualAddr = (*phe)->p_vaddr + (*phe)->p_filesz; @@ -247,153 +120,9 @@ (*endAtomIter)->_virtualAddr = (*phe)->p_vaddr + (*phe)->p_memsz; // Give a chance for the target to finalize its atom values - _targetHandler.finalizeSymbolValues(); -} - -template -error_code ExecutableWriter::writeFile(const File &file, StringRef path) { - buildChunks(file); - - // Call the preFlight callbacks to modify the sections and the atoms - // contained in them, in anyway the targets may want - _layout->doPreFlight(); - - // Create the default sections like the symbol table, string table, and the - // section string table - createDefaultSections(); - - if (_targetInfo.isDynamic()) { - _dynamicTable->createDefaultEntries(); - buildDynamicSymbolTable(file); - } - - // Set the Layout - _layout->assignSectionsToSegments(); - _layout->assignFileOffsets(); - _layout->assignVirtualAddress(); - - // Finalize the default value of symbols that the linker adds - finalizeDefaultAtomValues(); - - // Build the Atom To Address map for applying relocations - buildAtomToAddressMap(); - - // Create symbol table and section string table - buildStaticSymbolTable(file); - - // Finalize the layout by calling the finalize() functions - _layout->finalize(); - - // build Section Header table - buildSectionHeaderTable(); - - // assign Offsets and virtual addresses - // for sections with no segments - assignSectionsWithNoSegments(); - - if (_targetInfo.isDynamic()) - _dynamicTable->updateDynamicTable(_hashTable.get(), - _dynamicSymbolTable.get()); - - uint64_t totalSize = _shdrtab->fileOffset() + _shdrtab->fileSize(); - - OwningPtr buffer; - error_code ec = FileOutputBuffer::create(path, - totalSize, buffer, - FileOutputBuffer::F_executable); - if (ec) - return ec; - - _Header->e_ident(ELF::EI_CLASS, _targetInfo.is64Bits() ? ELF::ELFCLASS64 : - ELF::ELFCLASS32); - _Header->e_ident(ELF::EI_DATA, _targetInfo.isLittleEndian() ? - ELF::ELFDATA2LSB : ELF::ELFDATA2MSB); - _Header->e_type(_targetInfo.getOutputType()); - _Header->e_machine(_targetInfo.getOutputMachine()); - - if (!_targetHandler.doesOverrideHeader()) { - _Header->e_ident(ELF::EI_VERSION, 1); - _Header->e_ident(ELF::EI_OSABI, 0); - _Header->e_version(1); - } else { - // override the contents of the ELF Header - _targetHandler.setHeaderInfo(_Header.get()); - } - _Header->e_phoff(_programHeader->fileOffset()); - _Header->e_shoff(_shdrtab->fileOffset()); - _Header->e_phentsize(_programHeader->entsize()); - _Header->e_phnum(_programHeader->numHeaders()); - _Header->e_shentsize(_shdrtab->entsize()); - _Header->e_shnum(_shdrtab->numHeaders()); - _Header->e_shstrndx(_shstrtab->ordinal()); - uint64_t virtualAddr = 0; - _layout->findAtomAddrByName(_targetInfo.getEntry(), virtualAddr); - _Header->e_entry(virtualAddr); - - // HACK: We have to write out the header and program header here even though - // they are a member of a segment because only sections are written in the - // following loop. - _Header->write(this, *buffer); - _programHeader->write(this, *buffer); - - for (auto section : _layout->sections()) - section->write(this, *buffer); - - return buffer->commit(); + this->_targetHandler.finalizeSymbolValues(); } -template -void ExecutableWriter::createDefaultSections() { - _Header.reset(new (_alloc) Header(_targetInfo)); - _programHeader.reset(new (_alloc) ProgramHeader(_targetInfo)); - _layout->setHeader(_Header.get()); - _layout->setProgramHeader(_programHeader.get()); - - _symtab.reset(new (_alloc) SymbolTable( - _targetInfo, ".symtab", DefaultLayout::ORDER_SYMBOL_TABLE)); - _strtab.reset(new (_alloc) StringTable( - _targetInfo, ".strtab", DefaultLayout::ORDER_STRING_TABLE)); - _shstrtab.reset(new (_alloc) StringTable( - _targetInfo, ".shstrtab", DefaultLayout::ORDER_SECTION_STRINGS)); - _shdrtab.reset(new (_alloc) SectionHeader( - _targetInfo, DefaultLayout::ORDER_SECTION_HEADERS)); - _layout->addSection(_symtab.get()); - _layout->addSection(_strtab.get()); - _layout->addSection(_shstrtab.get()); - _shdrtab->setStringSection(_shstrtab.get()); - _symtab->setStringSection(_strtab.get()); - _layout->addSection(_shdrtab.get()); - - if (_targetInfo.isDynamic()) { - _dynamicTable.reset(new (_alloc) DynamicTable( - _targetInfo, ".dynamic", DefaultLayout::ORDER_DYNAMIC)); - _dynamicStringTable.reset(new (_alloc) StringTable( - _targetInfo, ".dynstr", DefaultLayout::ORDER_DYNAMIC_STRINGS, - true)); - _dynamicSymbolTable.reset(new (_alloc) DynamicSymbolTable( - _targetInfo, ".dynsym", DefaultLayout::ORDER_DYNAMIC_SYMBOLS)); - _interpSection.reset(new (_alloc) InterpSection( - _targetInfo, ".interp", DefaultLayout::ORDER_INTERP, - _targetInfo.getInterpreter())); - _hashTable.reset(new (_alloc) HashSection( - _targetInfo, ".hash", DefaultLayout::ORDER_HASH)); - _layout->addSection(_dynamicTable.get()); - _layout->addSection(_dynamicStringTable.get()); - _layout->addSection(_dynamicSymbolTable.get()); - _layout->addSection(_interpSection.get()); - _layout->addSection(_hashTable.get()); - _dynamicSymbolTable->setStringSection(_dynamicStringTable.get()); - if (_layout->hasDynamicRelocationTable()) - _layout->getDynamicRelocationTable()->setSymbolTable( - _dynamicSymbolTable.get()); - if (_layout->hasPLTRelocationTable()) - _layout->getPLTRelocationTable()->setSymbolTable( - _dynamicSymbolTable.get()); - } - - // give a chance for the target to add sections - _targetHandler.createDefaultSections(); -} } // namespace elf } // namespace lld Index: ELF/OutputELFWriter.h =================================================================== --- ELF/OutputELFWriter.h +++ ELF/OutputELFWriter.h @@ -0,0 +1,350 @@ +//===- lib/ReaderWriter/ELF/OutputELFWriter.h ----------------------------===// +// +// The LLVM Linker +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +#ifndef LLD_READER_WRITER_OUTPUT_ELF_WRITER_H +#define LLD_READER_WRITER_OUTPUT_ELF_WRITER_H + +#include "lld/ReaderWriter/Writer.h" + +#include "DefaultLayout.h" +#include "TargetLayout.h" +#include "ExecutableAtoms.h" + +#include "lld/ReaderWriter/ELFTargetInfo.h" + +#include "llvm/ADT/StringSet.h" + +namespace lld { +namespace elf { +using namespace llvm; +using namespace llvm::object; + +template +class OutputELFWriter; + +//===----------------------------------------------------------------------===// +// OutputELFWriter Class +//===----------------------------------------------------------------------===// +template +class OutputELFWriter : public ELFWriter { +public: + typedef Elf_Shdr_Impl Elf_Shdr; + typedef Elf_Sym_Impl Elf_Sym; + typedef Elf_Dyn_Impl Elf_Dyn; + + OutputELFWriter(const ELFTargetInfo &ti); + +protected: + // build the sections that need to be created + virtual void createDefaultSections(); + + // Build all the output sections + virtual void buildChunks(const File &file); + + // Build the output file + virtual error_code buildOutput(const File &file); + + // Write the file to the path specified + virtual error_code writeFile(const File &File, StringRef path); + + // Build the atom to address map, this has to be called + // before applying relocations + virtual void buildAtomToAddressMap(); + + // Build the symbol table for static linking + virtual void buildStaticSymbolTable(const File &file); + + // Build the dynamic symbol table for dynamic linking + virtual void buildDynamicSymbolTable(const File &file); + + // Build the section header table + virtual void buildSectionHeaderTable(); + + // Assign sections that have no segments such as the symbol table, + // section header table, string table etc + virtual void assignSectionsWithNoSegments(); + + // Add default atoms that need to be present in the output file + virtual void addDefaultAtoms() = 0; + + // Add any runtime files and their atoms to the output + virtual void addFiles(InputFiles&) = 0; + + // Finalize the default atom values + virtual void finalizeDefaultAtomValues() = 0; + + // This is called by the write section to apply relocations + virtual uint64_t addressOfAtom(const Atom *atom) { + return _atomToAddressMap[atom]; + } + + // This is a hook for creating default dynamic entries + virtual void createDefaultDynamicEntries() {} + + llvm::BumpPtrAllocator _alloc; + + const ELFTargetInfo &_targetInfo; + TargetHandler &_targetHandler; + + typedef llvm::DenseMap AtomToAddress; + AtomToAddress _atomToAddressMap; + TargetLayout *_layout; + LLD_UNIQUE_BUMP_PTR(Header) _Header; + LLD_UNIQUE_BUMP_PTR(ProgramHeader) _programHeader; + LLD_UNIQUE_BUMP_PTR(SymbolTable) _symtab; + LLD_UNIQUE_BUMP_PTR(StringTable) _strtab; + LLD_UNIQUE_BUMP_PTR(StringTable) _shstrtab; + LLD_UNIQUE_BUMP_PTR(SectionHeader) _shdrtab; + /// \name Dynamic sections. + /// @{ + LLD_UNIQUE_BUMP_PTR(DynamicTable) _dynamicTable; + LLD_UNIQUE_BUMP_PTR(DynamicSymbolTable) _dynamicSymbolTable; + LLD_UNIQUE_BUMP_PTR(StringTable) _dynamicStringTable; + LLD_UNIQUE_BUMP_PTR(InterpSection) _interpSection; + LLD_UNIQUE_BUMP_PTR(HashSection) _hashTable; + llvm::StringSet<> _soNeeded; + /// @} +}; + +//===----------------------------------------------------------------------===// +// OutputELFWriter +//===----------------------------------------------------------------------===// +template +OutputELFWriter::OutputELFWriter(const ELFTargetInfo &ti) + : _targetInfo(ti), _targetHandler(ti.getTargetHandler()) { + _layout = &_targetHandler.targetLayout(); +} + +template +void OutputELFWriter::buildChunks(const File &file) { + for (const DefinedAtom *definedAtom : file.defined()) { + _layout->addAtom(definedAtom); + } + for (const AbsoluteAtom *absoluteAtom : file.absolute()) + _layout->addAtom(absoluteAtom); +} + +template +void OutputELFWriter::buildStaticSymbolTable(const File &file) { + for (auto sec : _layout->sections()) + if (auto section = dyn_cast>(sec)) + for (const auto &atom : section->atoms()) + _symtab->addSymbol(atom->_atom, section->ordinal(), atom->_virtualAddr); + for (auto &atom : _layout->absoluteAtoms()) + _symtab->addSymbol(atom->_atom, ELF::SHN_ABS, atom->_virtualAddr); + for (const UndefinedAtom *a : file.undefined()) + _symtab->addSymbol(a, ELF::SHN_UNDEF); +} + +template +void OutputELFWriter::buildDynamicSymbolTable(const File &file) { + for (const auto sla : file.sharedLibrary()) { + _dynamicSymbolTable->addSymbol(sla, ELF::SHN_UNDEF); + _soNeeded.insert(sla->loadName()); + } + for (const auto &loadName : _soNeeded) { + Elf_Dyn dyn; + dyn.d_tag = DT_NEEDED; + dyn.d_un.d_val = _dynamicStringTable->addString(loadName.getKey()); + _dynamicTable->addEntry(dyn); + } +} + +template void OutputELFWriter::buildAtomToAddressMap() { + for (auto sec : _layout->sections()) + if (auto section = dyn_cast>(sec)) + for (const auto &atom : section->atoms()) + _atomToAddressMap[atom->_atom] = atom->_virtualAddr; + // build the atomToAddressMap that contains absolute symbols too + for (auto &atom : _layout->absoluteAtoms()) + _atomToAddressMap[atom->_atom] = atom->_virtualAddr; +} + +template +void OutputELFWriter::buildSectionHeaderTable() { + for (auto mergedSec : _layout->mergedSections()) { + if (mergedSec->kind() != Chunk::K_ELFSection && + mergedSec->kind() != Chunk::K_AtomSection) + continue; + if (mergedSec->hasSegment()) + _shdrtab->appendSection(mergedSec); + } +} + +template +void OutputELFWriter::assignSectionsWithNoSegments() { + for (auto mergedSec : _layout->mergedSections()) { + if (mergedSec->kind() != Chunk::K_ELFSection && + mergedSec->kind() != Chunk::K_AtomSection) + continue; + if (!mergedSec->hasSegment()) + _shdrtab->appendSection(mergedSec); + } + _layout->assignOffsetsForMiscSections(); + for (auto sec : _layout->sections()) + if (auto section = dyn_cast>(sec)) + if (!DefaultLayout::hasOutputSegment(section)) + _shdrtab->updateSection(section); +} + +template +void OutputELFWriter::createDefaultSections() { + _Header.reset(new (_alloc) Header(_targetInfo)); + _programHeader.reset(new (_alloc) ProgramHeader(_targetInfo)); + _layout->setHeader(_Header.get()); + _layout->setProgramHeader(_programHeader.get()); + + _symtab.reset(new (_alloc) SymbolTable( + _targetInfo, ".symtab", DefaultLayout::ORDER_SYMBOL_TABLE)); + _strtab.reset(new (_alloc) StringTable( + _targetInfo, ".strtab", DefaultLayout::ORDER_STRING_TABLE)); + _shstrtab.reset(new (_alloc) StringTable( + _targetInfo, ".shstrtab", DefaultLayout::ORDER_SECTION_STRINGS)); + _shdrtab.reset(new (_alloc) SectionHeader( + _targetInfo, DefaultLayout::ORDER_SECTION_HEADERS)); + _layout->addSection(_symtab.get()); + _layout->addSection(_strtab.get()); + _layout->addSection(_shstrtab.get()); + _shdrtab->setStringSection(_shstrtab.get()); + _symtab->setStringSection(_strtab.get()); + _layout->addSection(_shdrtab.get()); + + if (_targetInfo.isDynamic()) { + _dynamicTable.reset(new (_alloc) DynamicTable( + _targetInfo, ".dynamic", DefaultLayout::ORDER_DYNAMIC)); + _dynamicStringTable.reset(new (_alloc) StringTable( + _targetInfo, ".dynstr", DefaultLayout::ORDER_DYNAMIC_STRINGS, + true)); + _dynamicSymbolTable.reset(new (_alloc) DynamicSymbolTable( + _targetInfo, ".dynsym", DefaultLayout::ORDER_DYNAMIC_SYMBOLS)); + _interpSection.reset(new (_alloc) InterpSection( + _targetInfo, ".interp", DefaultLayout::ORDER_INTERP, + _targetInfo.getInterpreter())); + _hashTable.reset(new (_alloc) HashSection( + _targetInfo, ".hash", DefaultLayout::ORDER_HASH)); + _layout->addSection(_dynamicTable.get()); + _layout->addSection(_dynamicStringTable.get()); + _layout->addSection(_dynamicSymbolTable.get()); + _layout->addSection(_interpSection.get()); + _layout->addSection(_hashTable.get()); + _dynamicSymbolTable->setStringSection(_dynamicStringTable.get()); + if (_layout->hasDynamicRelocationTable()) + _layout->getDynamicRelocationTable()->setSymbolTable( + _dynamicSymbolTable.get()); + if (_layout->hasPLTRelocationTable()) + _layout->getPLTRelocationTable()->setSymbolTable( + _dynamicSymbolTable.get()); + } + + // give a chance for the target to add sections + _targetHandler.createDefaultSections(); +} + +template +error_code OutputELFWriter::buildOutput(const File &file) { + buildChunks(file); + + // Call the preFlight callbacks to modify the sections and the atoms + // contained in them, in anyway the targets may want + _layout->doPreFlight(); + + // Create the default sections like the symbol table, string table, and the + // section string table + createDefaultSections(); + + if (_targetInfo.isDynamic()) { + _dynamicTable->createDefaultEntries(); + buildDynamicSymbolTable(file); + } + + // Set the Layout + _layout->assignSectionsToSegments(); + _layout->assignFileOffsets(); + _layout->assignVirtualAddress(); + + // Finalize the default value of symbols that the linker adds + finalizeDefaultAtomValues(); + + // Build the Atom To Address map for applying relocations + buildAtomToAddressMap(); + + // Create symbol table and section string table + buildStaticSymbolTable(file); + + // Finalize the layout by calling the finalize() functions + _layout->finalize(); + + // build Section Header table + buildSectionHeaderTable(); + + // assign Offsets and virtual addresses + // for sections with no segments + assignSectionsWithNoSegments(); + + if (_targetInfo.isDynamic()) + _dynamicTable->updateDynamicTable(_hashTable.get(), + _dynamicSymbolTable.get()); + + return error_code::success(); +} + +template +error_code OutputELFWriter::writeFile(const File &file, StringRef path) { + + buildOutput(file); + + uint64_t totalSize = _shdrtab->fileOffset() + _shdrtab->fileSize(); + + OwningPtr buffer; + error_code ec = FileOutputBuffer::create(path, + totalSize, buffer, + FileOutputBuffer::F_executable); + if (ec) + return ec; + + _Header->e_ident(ELF::EI_CLASS, _targetInfo.is64Bits() ? ELF::ELFCLASS64 : + ELF::ELFCLASS32); + _Header->e_ident(ELF::EI_DATA, _targetInfo.isLittleEndian() ? + ELF::ELFDATA2LSB : ELF::ELFDATA2MSB); + _Header->e_type(_targetInfo.getOutputType()); + _Header->e_machine(_targetInfo.getOutputMachine()); + + if (!_targetHandler.doesOverrideHeader()) { + _Header->e_ident(ELF::EI_VERSION, 1); + _Header->e_ident(ELF::EI_OSABI, 0); + _Header->e_version(1); + } else { + // override the contents of the ELF Header + _targetHandler.setHeaderInfo(_Header.get()); + } + _Header->e_phoff(_programHeader->fileOffset()); + _Header->e_shoff(_shdrtab->fileOffset()); + _Header->e_phentsize(_programHeader->entsize()); + _Header->e_phnum(_programHeader->numHeaders()); + _Header->e_shentsize(_shdrtab->entsize()); + _Header->e_shnum(_shdrtab->numHeaders()); + _Header->e_shstrndx(_shstrtab->ordinal()); + uint64_t virtualAddr = 0; + _layout->findAtomAddrByName(_targetInfo.getEntry(), virtualAddr); + _Header->e_entry(virtualAddr); + + // HACK: We have to write out the header and program header here even though + // they are a member of a segment because only sections are written in the + // following loop. + _Header->write(this, *buffer); + _programHeader->write(this, *buffer); + + for (auto section : _layout->sections()) + section->write(this, *buffer); + + return buffer->commit(); +} +} // namespace elf +} // namespace lld + +#endif // LLD_READER_WRITER_OUTPUT_ELF_WRITER_H