//===----------------------------------------------------------------------===//
// X86GNULDBackend
//===----------------------------------------------------------------------===//
X86GNULDBackend::X86GNULDBackend(const LinkerConfig& pConfig,
GNUInfo* pInfo,
Relocation::Type pCopyRel)
: GNULDBackend(pConfig, pInfo),
m_pRelocator(NULL),
m_pPLT(NULL),
m_pRelDyn(NULL),
m_pRelPLT(NULL),
m_pDynamic(NULL),
m_pGOTSymbol(NULL),
m_CopyRel(pCopyRel)
{
Triple::ArchType arch = pConfig.targets().triple().getArch();
assert (arch == Triple::x86 || arch == Triple::x86_64);
if (arch == Triple::x86 ||
pConfig.targets().triple().getEnvironment() == Triple::GNUX32) {
m_RelEntrySize = 8;
m_RelaEntrySize = 12;
if (arch == Triple::x86)
m_PointerRel = llvm::ELF::R_386_32;
else
m_PointerRel = llvm::ELF::R_X86_64_32;
}
else {
m_RelEntrySize = 16;
m_RelaEntrySize = 24;
m_PointerRel = llvm::ELF::R_X86_64_64;
}
}
static bool MCLDEmulateX86ELF(LinkerScript& pScript, LinkerConfig& pConfig)
{
if (!MCLDEmulateELF(pScript, pConfig))
return false;
// set up bitclass and endian
pConfig.targets().setEndian(TargetOptions::Little);
unsigned int bitclass;
Triple::ArchType arch = pConfig.targets().triple().getArch();
assert (arch == Triple::x86 || arch == Triple::x86_64);
if (arch == Triple::x86 ||
pConfig.targets().triple().getEnvironment() == Triple::GNUX32) {
bitclass = 32;
}
else {
bitclass = 64;
}
pConfig.targets().setBitClass(bitclass);
// set up target-dependent constraints of attributes
pConfig.attribute().constraint().enableWholeArchive();
pConfig.attribute().constraint().enableAsNeeded();
pConfig.attribute().constraint().setSharedSystem();
// set up the predefined attributes
pConfig.attribute().predefined().unsetWholeArchive();
pConfig.attribute().predefined().unsetAsNeeded();
pConfig.attribute().predefined().setDynamic();
return true;
}
static bool MCLDEmulateARMELF(LinkerConfig& pConfig)
{
if (!MCLDEmulateELF(pConfig))
return false;
// set up bitclass and endian
pConfig.targets().setEndian(TargetOptions::Little);
pConfig.targets().setBitClass(32);
// set up target-dependent constraints of attributes
pConfig.attribute().constraint().enableWholeArchive();
pConfig.attribute().constraint().enableAsNeeded();
pConfig.attribute().constraint().setSharedSystem();
// set up the predefined attributes
pConfig.attribute().predefined().unsetWholeArchive();
pConfig.attribute().predefined().unsetAsNeeded();
pConfig.attribute().predefined().setDynamic();
// set up section map
if (pConfig.codeGenType() != LinkerConfig::Object) {
bool exist = false;
pConfig.scripts().sectionMap().append(".ARM.exidx", ".ARM.exidx", exist);
pConfig.scripts().sectionMap().append(".ARM.extab", ".ARM.extab", exist);
pConfig.scripts().sectionMap().append(".ARM.attributes", ".ARM.attributes", exist);
}
return true;
}
//===----------------------------------------------------------------------===//
// ELFDynObjReader
//===----------------------------------------------------------------------===//
ELFDynObjReader::ELFDynObjReader(GNULDBackend& pBackend,
IRBuilder& pBuilder,
const LinkerConfig& pConfig)
: DynObjReader(),
m_pELFReader(0),
m_Builder(pBuilder) {
if (pConfig.targets().is32Bits() && pConfig.targets().isLittleEndian())
m_pELFReader = new ELFReader<32, true>(pBackend);
else if (pConfig.targets().is64Bits() && pConfig.targets().isLittleEndian())
m_pELFReader = new ELFReader<64, true>(pBackend);
}
//===----------------------------------------------------------------------===//
// emulateX86LD - the help function to emulate X86 ld
//===----------------------------------------------------------------------===//
bool emulateX86LD(LinkerScript& pScript, LinkerConfig& pConfig)
{
if (pConfig.targets().triple().isOSDarwin()) {
assert(0 && "MachO linker has not supported yet");
return false;
}
if (pConfig.targets().triple().isOSWindows()) {
assert(0 && "COFF linker has not supported yet");
return false;
}
return MCLDEmulateX86ELF(pScript, pConfig);
}
/// emitRelocation
void ELFObjectWriter::emitRelocation(const LinkerConfig& pConfig,
const LDSection& pSection,
MemoryRegion& pRegion) const
{
const RelocData* sect_data = pSection.getRelocData();
assert(NULL != sect_data && "SectionData is NULL in emitRelocation!");
if (pSection.type() == SHT_REL) {
if (pConfig.targets().is32Bits())
emitRel<32>(pConfig, *sect_data, pRegion);
else if (pConfig.targets().is64Bits())
emitRel<64>(pConfig, *sect_data, pRegion);
else {
fatal(diag::unsupported_bitclass) << pConfig.targets().triple().str()
<< pConfig.targets().bitclass();
}
} else if (pSection.type() == SHT_RELA) {
if (pConfig.targets().is32Bits())
emitRela<32>(pConfig, *sect_data, pRegion);
else if (pConfig.targets().is64Bits())
emitRela<64>(pConfig, *sect_data, pRegion);
else {
fatal(diag::unsupported_bitclass) << pConfig.targets().triple().str()
<< pConfig.targets().bitclass();
}
} else
llvm::report_fatal_error("unsupported relocation section type!");
}
/// configure the output filename
bool OutputFormatOptions::parseOutput(Module& pModule, LinkerConfig& pConfig)
{
if (true == m_Shared || true == m_PIE) {
// -shared or -pie
m_FileType = mcld::LinkerConfig::DynObj;
}
else if (true == m_Relocatable) {
// partial linking
m_FileType = mcld::LinkerConfig::Object;
}
else if (mcld::LinkerConfig::Binary == m_OFormat) {
// binary output
m_FileType = mcld::LinkerConfig::Binary;
}
pConfig.setCodeGenType(m_FileType);
std::string output_filename(m_OutputFilename.native());
if (m_OutputFilename.empty()) {
if (llvm::Triple::Win32 == pConfig.targets().triple().getOS()) {
output_filename.assign("_out");
switch (m_FileType) {
case mcld::LinkerConfig::Object: {
output_filename += ".obj";
break;
}
case mcld::LinkerConfig::DynObj: {
output_filename += ".dll";
break;
}
case mcld::LinkerConfig::Exec: {
output_filename += ".exe";
break;
}
case mcld::LinkerConfig::External:
break;
default: {
return false;
break;
}
} // switch
}
else {
if (mcld::LinkerConfig::Object == m_FileType ||
mcld::LinkerConfig::DynObj == m_FileType ||
mcld::LinkerConfig::Exec == m_FileType ||
mcld::LinkerConfig::External == m_FileType) {
output_filename.assign("a.out");
}
else {
return false;
}
}
} // end of if empty m_OutputFilename
pModule.setName(output_filename);
return true;
}
// FIXME: LinkerConfig& pConfig should be constant
bool MCLDEmulateELF(LinkerScript& pScript, LinkerConfig& pConfig) {
// set up section map
if (pConfig.options().getScriptList().empty() &&
pConfig.codeGenType() != LinkerConfig::Object) {
const unsigned int map_size = (sizeof(map) / sizeof(map[0]));
for (unsigned int i = 0; i < map_size; ++i) {
std::pair<SectionMap::mapping, bool> res =
pScript.sectionMap().insert(map[i].from, map[i].to, map[i].policy);
if (!res.second)
return false;
}
} else {
// FIXME: this is the hack to help assignment processing in current
// implementation.
pScript.sectionMap().insert("", "");
}
if (!pConfig.options().nostdlib()) {
// TODO: check if user sets the default search path instead via -Y option
// set up default search path
switch (pConfig.targets().triple().getOS()) {
case llvm::Triple::NetBSD:
pScript.directories().insert("=/usr/lib");
break;
case llvm::Triple::Win32:
pScript.directories().insert("=/mingw/lib");
break;
default:
pScript.directories().insert("=/lib");
pScript.directories().insert("=/usr/lib");
break;
}
}
return true;
}
//===----------------------------------------------------------------------===//
// ELFObjectReader
//===----------------------------------------------------------------------===//
/// constructor
ELFObjectReader::ELFObjectReader(GNULDBackend& pBackend,
IRBuilder& pBuilder,
const LinkerConfig& pConfig)
: ObjectReader(),
m_pELFReader(NULL),
m_pEhFrameReader(NULL),
m_Builder(pBuilder),
m_ReadFlag(ParseEhFrame),
m_Backend(pBackend),
m_Config(pConfig) {
if (pConfig.targets().is32Bits() && pConfig.targets().isLittleEndian()) {
m_pELFReader = new ELFReader<32, true>(pBackend);
}
else if (pConfig.targets().is64Bits() && pConfig.targets().isLittleEndian()) {
m_pELFReader = new ELFReader<64, true>(pBackend);
}
m_pEhFrameReader = new EhFrameReader();
}
void ELFObjectWriter::writeELFHeader(const LinkerConfig& pConfig,
const Module& pModule,
MemoryArea& pOutput) const
{
typedef typename ELFSizeTraits<SIZE>::Ehdr ElfXX_Ehdr;
typedef typename ELFSizeTraits<SIZE>::Shdr ElfXX_Shdr;
typedef typename ELFSizeTraits<SIZE>::Phdr ElfXX_Phdr;
// ELF header must start from 0x0
MemoryRegion *region = pOutput.request(0, sizeof(ElfXX_Ehdr));
ElfXX_Ehdr* header = (ElfXX_Ehdr*)region->start();
memcpy(header->e_ident, ElfMagic, EI_MAG3+1);
header->e_ident[EI_CLASS] = (SIZE == 32) ? ELFCLASS32 : ELFCLASS64;
header->e_ident[EI_DATA] = pConfig.targets().isLittleEndian()?
ELFDATA2LSB : ELFDATA2MSB;
header->e_ident[EI_VERSION] = target().getInfo().ELFVersion();
header->e_ident[EI_OSABI] = target().getInfo().OSABI();
header->e_ident[EI_ABIVERSION] = target().getInfo().ABIVersion();
// FIXME: add processor-specific and core file types.
switch(pConfig.codeGenType()) {
case LinkerConfig::Object:
header->e_type = ET_REL;
break;
case LinkerConfig::DynObj:
header->e_type = ET_DYN;
break;
case LinkerConfig::Exec:
header->e_type = ET_EXEC;
break;
default:
llvm::errs() << "unspported output file type: " << pConfig.codeGenType() << ".\n";
header->e_type = ET_NONE;
}
header->e_machine = target().getInfo().machine();
header->e_version = header->e_ident[EI_VERSION];
header->e_entry = getEntryPoint(pConfig, pModule);
if (LinkerConfig::Object != pConfig.codeGenType())
header->e_phoff = sizeof(ElfXX_Ehdr);
else
header->e_phoff = 0x0;
header->e_shoff = getLastStartOffset<SIZE>(pModule);
header->e_flags = target().getInfo().flags();
header->e_ehsize = sizeof(ElfXX_Ehdr);
header->e_phentsize = sizeof(ElfXX_Phdr);
header->e_phnum = target().elfSegmentTable().size();
header->e_shentsize = sizeof(ElfXX_Shdr);
header->e_shnum = pModule.size();
header->e_shstrndx = pModule.getSection(".shstrtab")->index();
}
static bool MCLDEmulateHexagonELF(LinkerConfig& pConfig)
{
if (!MCLDEmulateELF(pConfig))
return false;
// set up bitclass and endian
pConfig.targets().setEndian(TargetOptions::Little);
pConfig.targets().setBitClass(32);
// set up target-dependent constraints of attributes
pConfig.attribute().constraint().enableWholeArchive();
pConfig.attribute().constraint().enableAsNeeded();
pConfig.attribute().constraint().setSharedSystem();
// set up the predefined attributes
pConfig.attribute().predefined().unsetWholeArchive();
pConfig.attribute().predefined().unsetAsNeeded();
pConfig.attribute().predefined().setDynamic();
return true;
}
/// includeMember - include the object member in the given file offset, and
/// return the size of the object
/// @param pConfig - LinkerConfig
/// @param pArchiveRoot - the archive root
/// @param pFileOffset - file offset of the member header in the archive
size_t GNUArchiveReader::includeMember(const LinkerConfig& pConfig,
Archive& pArchive,
uint32_t pFileOffset)
{
Input* cur_archive = &(pArchive.getARFile());
Input* member = NULL;
uint32_t file_offset = pFileOffset;
size_t size = 0;
do {
uint32_t nested_offset = 0;
// use the file offset in current archive to find out the member we
// want to include
member = readMemberHeader(pArchive,
*cur_archive,
file_offset,
nested_offset,
size);
assert(member != NULL);
// bypass if we get an archive that is already in the map
if (Input::Archive == member->type()) {
cur_archive = member;
file_offset = nested_offset;
continue;
}
// insert a node into the subtree of current archive.
Archive::ArchiveMember* parent =
pArchive.getArchiveMember(cur_archive->name());
assert(NULL != parent);
pArchive.inputs().insert(parent->lastPos, *(parent->move), *member);
// move the iterator to new created node, and also adjust the
// direction to Afterward for next insertion in this subtree
parent->move->move(parent->lastPos);
parent->move = &InputTree::Afterward;
bool doContinue = false;
if (m_ELFObjectReader.isMyFormat(*member, doContinue)) {
member->setType(Input::Object);
pArchive.addObjectMember(pFileOffset, parent->lastPos);
m_ELFObjectReader.readHeader(*member);
m_ELFObjectReader.readSections(*member);
m_ELFObjectReader.readSymbols(*member);
m_Module.getObjectList().push_back(member);
}
else if (doContinue && isMyFormat(*member, doContinue)) {
member->setType(Input::Archive);
// when adding a new archive node, set the iterator to archive
// itself, and set the direction to Downward
pArchive.addArchiveMember(member->name(),
parent->lastPos,
&InputTree::Downward);
cur_archive = member;
file_offset = nested_offset;
}
else {
warning(diag::warn_unrecognized_input_file) << member->path()
<< pConfig.targets().triple().str();
}
} while (Input::Object != member->type());
return size;
}
bool GroupReader::readGroup(Module::input_iterator pRoot,
InputBuilder& pBuilder,
const LinkerConfig& pConfig)
{
// record the number of total objects included in this sub-tree
size_t cur_obj_cnt = 0;
size_t last_obj_cnt = 0;
size_t non_ar_obj_cnt = 0;
// record the archive files in this sub-tree
typedef std::vector<ArchiveListEntry*> ArchiveListType;
ArchiveListType ar_list;
Module::input_iterator input = --pRoot;
// Since the end of a sub-tree is the same node to the end of whole tree, we
// take the end of the whole input tree for conventience.
Module::input_iterator input_end = m_Module.input_end();
// first time read the sub-tree
while (input != input_end) {
// already got type - for example, bitcode or external OIR (object
// intermediate representation)
if ((*input)->type() == Input::Script ||
(*input)->type() == Input::Object ||
(*input)->type() == Input::DynObj ||
(*input)->type() == Input::Archive ||
(*input)->type() == Input::External) {
++input;
continue;
}
// is an archive
if (m_ArchiveReader.isMyFormat(**input)) {
(*input)->setType(Input::Archive);
// record the Archive used by each archive node
Archive* ar = new Archive(**input, pBuilder);
ArchiveListEntry* entry = new ArchiveListEntry(*ar, input);
ar_list.push_back(entry);
// read archive
m_ArchiveReader.readArchive(*ar);
cur_obj_cnt += ar->numOfObjectMember();
}
// is a relocatable object file
else if (m_ObjectReader.isMyFormat(**input)) {
(*input)->setType(Input::Object);
m_ObjectReader.readHeader(**input);
m_ObjectReader.readSections(**input);
m_ObjectReader.readSymbols(**input);
m_Module.getObjectList().push_back(*input);
++cur_obj_cnt;
++non_ar_obj_cnt;
}
// is a shared object file
else if (m_DynObjReader.isMyFormat(**input)) {
(*input)->setType(Input::DynObj);
m_DynObjReader.readHeader(**input);
m_DynObjReader.readSymbols(**input);
m_Module.getLibraryList().push_back(*input);
}
else {
fatal(diag::err_unrecognized_input_file) << (*input)->path()
<< pConfig.targets().triple().str();
}
++input;
}
// after read in all the archives, traverse the archive list in a loop until
// there is no unresolved symbols added
ArchiveListType::iterator it = ar_list.begin();
ArchiveListType::iterator end = ar_list.end();
while (cur_obj_cnt != last_obj_cnt) {
last_obj_cnt = cur_obj_cnt;
cur_obj_cnt = non_ar_obj_cnt;
for (it = ar_list.begin(); it != end; ++it) {
Archive& ar = (*it)->archive;
// if --whole-archive is given to this archive, no need to read it again
if ( ar.getARFile().attribute()->isWholeArchive())
continue;
m_ArchiveReader.readArchive(ar);
cur_obj_cnt += ar.numOfObjectMember();
}
}
// after all needed member included, merge the archive sub-tree to main
// InputTree
for (it = ar_list.begin(); it != end; ++it) {
Archive& ar = (*it)->archive;
if (ar.numOfObjectMember() > 0) {
m_Module.getInputTree().merge<InputTree::Inclusive>((*it)->input,
ar.inputs());
}
}
// cleanup ar_list
for (it = ar_list.begin(); it != end; ++it) {
delete &((*it)->archive);
delete (*it);
}
ar_list.clear();
return true;
}