- else {
- if ( atom.dontDeadStrip() )
- fLiveRootAtoms.insert(&atom);
- }
-
- // if in global namespace, add atom itself to symbol table
- ObjectFile::Atom::Scope scope = atom.getScope();
- const char* name = atom.getName();
- if ( (scope != ObjectFile::Atom::scopeTranslationUnit) && (name != NULL) ) {
- // add to symbol table
- fGlobalSymbolTable.add(atom);
- }
-
- // record section orders so output file can have same order
- if (atom.getSectionName()) {
- bool untrusted = false;
- switch ( atom.getContentType() ) {
- case ObjectFile::Atom::kSectionStart:
- case ObjectFile::Atom::kSectionEnd:
- untrusted = true;
- default:
- break;
- }
- atom.setSection(Section::find(atom.getSectionName(), atom.getSegment().getName(), atom.isZeroFill(), untrusted));
- }
-}
-
-
-void Linker::markDead(ObjectFile::Atom* atom)
-{
- //fprintf(stderr, "markDead(%p) %s from %s\n", atom, atom->getDisplayName(), atom->getFile()->getPath());
- fDeadAtoms.insert(atom);
-
- // <rdar://problem/6578360> -dead_strip inhibits weak coalescing in no_dead_strip section
- if ( fLiveRootAtoms.count(atom) != 0 ) {
- fLiveRootAtoms.erase(atom);
- }
-
- //
- // The kGroupSubordinate reference kind is used to model group comdat.
- // The "signature" atom in the group has a kGroupSubordinate reference to
- // all other members of the group. So, if the signature atom is
- // coalesced away, all other atoms in the group should also be removed.
- //
- std::vector<class ObjectFile::Reference*>& references = atom->getReferences();
- for (std::vector<ObjectFile::Reference*>::iterator rit=references.begin(); rit != references.end(); rit++) {
- ObjectFile::Reference* ref = *rit;
- if ( ref->getKind() == 2 /*kGroupSubordinate*/ ) { // FIX FIX
- ObjectFile::Atom* targetAtom = &(ref->getTarget());
- //fprintf(stderr, " markDead(%p) subordinate %s\n", targetAtom, targetAtom->getDisplayName());
- if ( targetAtom == NULL ) {
- warning("%s has a group reference to %s but is not bound", atom->getDisplayName(), ref->getTargetName());
- }
- else {
- if ( targetAtom->getScope() != ObjectFile::Atom::scopeTranslationUnit ) {
- // ok for .eh symbols to be not static in -r mode
- if ( (fOptions.outputKind() != Options::kObjectFile) || (strcmp(targetAtom->getSectionName(), "__eh_frame") != 0) )
- warning("%s is in a comdat group but its scope is not static", targetAtom->getDisplayName());
- }
- this->markDead(targetAtom);
- }
- }
- }
-}
-
-void Linker::updateConstraints(ObjectFile::Reader* reader)
-{
- // check objc objects were compiled compatibly
- ObjectFile::Reader::ObjcConstraint objcAddition = reader->getObjCConstraint();
- if ( reader->getInstallPath() == NULL ) {
- // adding a .o file
- switch ( objcAddition ) {
- case ObjectFile::Reader::kObjcNone:
- break;
- case ObjectFile::Reader::kObjcRetainRelease:
- if ( fCurrentObjCConstraint == ObjectFile::Reader::kObjcGC )
- throwf("%s built with incompatible Garbage Collection settings to link with previous .o files", reader->getPath());
- fCurrentObjCConstraint = ObjectFile::Reader::kObjcRetainRelease;
- break;
- case ObjectFile::Reader::kObjcRetainReleaseOrGC:
- if ( fCurrentObjCConstraint == ObjectFile::Reader::kObjcNone )
- fCurrentObjCConstraint = ObjectFile::Reader::kObjcRetainReleaseOrGC;
- break;
- case ObjectFile::Reader::kObjcGC:
- if ( fCurrentObjCConstraint == ObjectFile::Reader::kObjcRetainRelease )
- throwf("%s built with incompatible Garbage Collection settings to link with previous .o files", reader->getPath());
- fCurrentObjCConstraint = ObjectFile::Reader::kObjcGC;
- break;
- }
- }
- if ( reader->objcReplacementClasses() )
- fObjcReplacmentClasses = true;
-
- // check cpu sub-types for stricter sub-type
- fCurrentCpuConstraint = (ObjectFile::Reader::CpuConstraint)reader->updateCpuConstraint(fCurrentCpuConstraint);
-}
-
-inline void Linker::addAtoms(std::vector<class ObjectFile::Atom*>& atoms)
-{
- bool scanAll = fOptions.readerOptions().fFullyLoadArchives || fOptions.readerOptions().fLoadAllObjcObjectsFromArchives;
- bool first = true;
- for (std::vector<ObjectFile::Atom*>::iterator it=atoms.begin(); it != atoms.end(); it++) {
- // usually we only need to get the first atom's reader, but
- // with -all_load all atoms from all .o files come come back together
- // so we need to scan all atoms
- if ( first || scanAll ) {
- // update fReadersThatHaveSuppliedAtoms
- ObjectFile::Reader* reader = (*it)->getFile();
- if ( std::find(fReadersThatHaveSuppliedAtoms.begin(), fReadersThatHaveSuppliedAtoms.end(), reader)
- == fReadersThatHaveSuppliedAtoms.end() ) {
- fReadersThatHaveSuppliedAtoms.push_back(reader);
- updateConstraints(reader);
- }
- }
- this->addAtom(**it);
- first = false;
- }
-}
-
-void Linker::logArchive(ObjectFile::Reader* reader)
-{
- if ( (fArchiveReaders.count(reader) != 0) && (fArchiveReadersLogged.count(reader) == 0) ) {
- fArchiveReadersLogged.insert(reader);
- const char* fullPath = reader->getPath();
- char realName[MAXPATHLEN];
- if ( realpath(fullPath, realName) != NULL )
- fullPath = realName;
- logTraceInfo("[Logging for XBS] Used static archive: %s\n", fullPath);
- }
-}
-
-
-void Linker::buildAtomList()
-{
- fStartBuildAtomsTime = mach_absolute_time();
- // add initial undefines from -u option
- std::vector<const char*>& initialUndefines = fOptions.initialUndefines();
- for (std::vector<const char*>::iterator it=initialUndefines.begin(); it != initialUndefines.end(); it++) {
- fGlobalSymbolTable.require(*it);
- }
-
- // writer can contribute atoms
- this->addAtoms(fOutputFile->getAtoms());
-
- // each reader contributes atoms
- for (std::vector<class ObjectFile::Reader*>::iterator it=fInputFiles.begin(); it != fInputFiles.end(); it++) {
- ObjectFile::Reader* reader = *it;
- std::vector<class ObjectFile::Atom*>& atoms = reader->getAtoms();
- this->addAtoms(atoms);
- if ( fOptions.readerOptions().fTraceArchives && (atoms.size() != 0) )
- logArchive(reader);
- }
-
- // extra command line section always at end
- std::vector<Options::ExtraSection>& extraSections = fOptions.extraSections();
- for( std::vector<Options::ExtraSection>::iterator it=extraSections.begin(); it != extraSections.end(); ++it) {
- this->addAtoms((new opaque_section::Reader(it->segmentName, it->sectionName, it->path, it->data, it->dataLen, fNextInputOrdinal))->getAtoms());
- fNextInputOrdinal += it->dataLen;
- }
-
- // done with all .o files on command line
- // everything loaded from now on is a just-in-time atom
- fInitialLoadsDone = true;
-}
-
-static const char* pathLeafName(const char* path)
-{
- const char* shortPath = strrchr(path, '/');
- if ( shortPath == NULL )
- return path;
- else
- return &shortPath[1];
-}
-
-
-void Linker::loadUndefines()
-{
- // keep looping until no more undefines were added in last loop
- unsigned int undefineCount = 0xFFFFFFFF;
- while ( undefineCount != fGlobalSymbolTable.getRequireCount() ) {
- undefineCount = fGlobalSymbolTable.getRequireCount();
- std::vector<const char*> undefineNames;
- fGlobalSymbolTable.getUndefinesNames(undefineNames);
- for(std::vector<const char*>::iterator it = undefineNames.begin(); it != undefineNames.end(); ++it) {
- // load for previous undefine may also have loaded this undefine, so check again
- if ( fGlobalSymbolTable.find(*it) == NULL ) {
- std::vector<class ObjectFile::Atom*>* atoms = this->addJustInTimeAtoms(*it, true, true, true);
- if ( atoms != NULL )
- delete atoms;
- }
- }
- // <rdar://problem/5894163> need to search archives for overrides of common symbols
- if ( fGlobalSymbolTable.hasExternalTentativeDefinitions() ) {
- bool searchDylibs = (fOptions.commonsMode() == Options::kCommonsOverriddenByDylibs);
- std::vector<const char*> tentativeDefinitionNames;
- fGlobalSymbolTable.getTentativesNames(tentativeDefinitionNames);
- for(std::vector<const char*>::iterator it = tentativeDefinitionNames.begin(); it != tentativeDefinitionNames.end(); ++it) {
- // load for previous tentative may also have overridden this tentative, so check again
- ObjectFile::Atom* tent = fGlobalSymbolTable.find(*it);
- if ( (tent != NULL) && (tent->getDefinitionKind() == ObjectFile::Atom::kTentativeDefinition) ) {
- std::vector<class ObjectFile::Atom*>* atoms = this->addJustInTimeAtoms(*it, searchDylibs, true, false);
- if ( atoms != NULL )
- delete atoms;
- }
- }
- }
- }
-}
-
-// temp hack for rdar://problem/4718189 map ObjC class names to new runtime names
-class ExportedObjcClass
-{
-public:
- ExportedObjcClass(Options& opt) : fOptions(opt) {}
-
- bool operator()(const char* name) const {
- if ( fOptions.shouldExport(name) ) {
- if ( strncmp(name, ".objc_class_name_", 17) == 0 )
- return true;
- if ( strncmp(name, "_OBJC_CLASS_$_", 14) == 0 )
- return true;
- if ( strncmp(name, "_OBJC_METACLASS_$_", 18) == 0 )
- return true;
- }
- //fprintf(stderr, "%s is not exported\n", name);
- return false;
- }
-private:
- Options& fOptions;
-};
-
-
-void Linker::checkUndefines()
-{
- // error out on any remaining undefines
- bool doPrint = true;
- bool doError = true;
- switch ( fOptions.undefinedTreatment() ) {
- case Options::kUndefinedError:
- break;
- case Options::kUndefinedDynamicLookup:
- doError = false;
- break;
- case Options::kUndefinedWarning:
- doError = false;
- break;
- case Options::kUndefinedSuppress:
- doError = false;
- doPrint = false;
- break;
- }
- std::vector<const char*> unresolvableUndefines;
- fGlobalSymbolTable.getUndefinesNames(unresolvableUndefines);
-
- // temp hack for rdar://problem/4718189 map ObjC class names to new runtime names
- // ignore unresolved references to Objc class names that are listed in -exported_symbols_list
- if ( fOptions.hasExportRestrictList() )
- unresolvableUndefines.erase(std::remove_if(unresolvableUndefines.begin(), unresolvableUndefines.end(), ExportedObjcClass(fOptions)), unresolvableUndefines.end());
-
- const int unresolvableCount = unresolvableUndefines.size();
- int unresolvableExportsCount = 0;
- if ( unresolvableCount != 0 ) {
- if ( doPrint ) {
- if ( fOptions.printArchPrefix() )
- fprintf(stderr, "Undefined symbols for architecture %s:\n", fArchitectureName);
- else
- fprintf(stderr, "Undefined symbols:\n");
- for (int i=0; i < unresolvableCount; ++i) {
- const char* name = unresolvableUndefines[i];
- fprintf(stderr, " \"%s\", referenced from:\n", name);
- // scan all atoms for references
- bool foundAtomReference = false;
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- ObjectFile::Atom* atom = *it;
- std::vector<class ObjectFile::Reference*>& references = atom->getReferences();
- for (std::vector<ObjectFile::Reference*>::iterator rit=references.begin(); rit != references.end(); rit++) {
- ObjectFile::Reference* reference = *rit;
- if ( reference->getTargetBinding() == ObjectFile::Reference::kUnboundByName ) {
- if ( strcmp(reference->getTargetName(), name) == 0 ) {
- fprintf(stderr, " %s in %s\n", atom->getDisplayName(), pathLeafName(atom->getFile()->getPath()));
- foundAtomReference = true;
- }
- }
- if ( reference->getFromTargetBinding() == ObjectFile::Reference::kUnboundByName ) {
- if ( strcmp(reference->getFromTargetName(), name) == 0 ) {
- fprintf(stderr, " %s in %s\n", atom->getDisplayName(), pathLeafName(atom->getFile()->getPath()));
- foundAtomReference = true;
- }
- }
- }
- }
- // scan command line options
- if ( !foundAtomReference ) {
- // might be from -init command line option
- if ( (fOptions.initFunctionName() != NULL) && (strcmp(name, fOptions.initFunctionName()) == 0) ) {
- fprintf(stderr, " -init command line option\n");
- }
- // or might be from exported symbol option
- else if ( fOptions.hasExportMaskList() && fOptions.shouldExport(name) ) {
- fprintf(stderr, " -exported_symbol[s_list] command line option\n");
- }
- else {
- bool isInitialUndefine = false;
- std::vector<const char*>& clundefs = fOptions.initialUndefines();
- for (std::vector<const char*>::iterator uit = clundefs.begin(); uit != clundefs.end(); ++uit) {
- if ( strcmp(*uit, name) == 0 ) {
- isInitialUndefine = true;
- break;
- }
- }
- if ( isInitialUndefine )
- fprintf(stderr, " -u command line option\n");
- }
- ++unresolvableExportsCount;
- }
- // be helpful and check for typos
- bool printedStart = false;
- for (SymbolTable::Mapper::iterator sit=fGlobalSymbolTable.begin(); sit != fGlobalSymbolTable.end(); ++sit) {
- if ( (sit->second != NULL) && (strstr(sit->first, name) != NULL) ) {
- if ( ! printedStart ) {
- fprintf(stderr, " (maybe you meant: %s", sit->first);
- printedStart = true;
- }
- else {
- fprintf(stderr, ", %s ", sit->first);
- }
- }
- }
- if ( printedStart )
- fprintf(stderr, ")\n");
- }
- }
- if ( doError )
- throw "symbol(s) not found";
- }
-
- // for each tentative definition in symbol table look for dylib that exports same symbol name
- if ( fGlobalSymbolTable.hasExternalTentativeDefinitions() ) {
- for (SymbolTable::Mapper::iterator it=fGlobalSymbolTable.begin(); it != fGlobalSymbolTable.end(); ++it) {
- ObjectFile::Atom* atom = it->second;
- if ( (atom != NULL) && (atom->getDefinitionKind()==ObjectFile::Atom::kTentativeDefinition)
- && (atom->getScope() == ObjectFile::Atom::scopeGlobal) ) {
- // look for dylibs that export same name as used by global tentative definition
- addJustInTimeAtoms(atom->getName(), true, false, false);
- }
- }
- }
-
-
- // record any overrides of weak symbols any linked dylib
- for (SymbolTable::Mapper::iterator it=fGlobalSymbolTable.begin(); it != fGlobalSymbolTable.end(); ++it) {
- ObjectFile::Atom* atom = it->second;
- if ( (atom != NULL) && (atom->getDefinitionKind()==ObjectFile::Atom::kRegularDefinition)
- && (atom->getScope() == ObjectFile::Atom::scopeGlobal) ) {
- const char* name = atom->getName();
- //fprintf(stderr, "looking for dylibs with a weak %s\n", name);
- // look for dylibs with weak exports of the same name
- for (InstallNameToReader::iterator it=fDylibMap.begin(); it != fDylibMap.end(); it++) {
- ObjectFile::Reader* reader = it->second;
- if ( reader->hasWeakExternals() ) {
- std::vector<class ObjectFile::Atom*>* dylibAtoms = reader->getJustInTimeAtomsFor(name);
- if ( dylibAtoms != NULL ) {
- //fprintf(stderr, "addJustInTimeAtoms(%s) => found in file %s\n", name, reader->getPath() );
- // if this is a weak definition in a dylib
- if ( (dylibAtoms->at(0)->getDefinitionKind() == ObjectFile::Atom::kExternalWeakDefinition) ) {
- fRegularDefAtomsThatOverrideADylibsWeakDef.insert(atom);
- }
- }
- }
- }
- }
- }
-
-}
-
-
-
-std::vector<class ObjectFile::Atom*>* Linker::addJustInTimeAtoms(const char* name, bool searchDylibs, bool searchArchives, bool okToMakeProxy)
-{
- //fprintf(stderr, "addJustInTimeAtoms(%s, searchDylibs=%d, searchArchives=%d)\n", name, searchDylibs, searchArchives );
- // when creating final linked image, writer gets first chance
- if ( fOptions.outputKind() != Options::kObjectFile ) {
- std::vector<class ObjectFile::Atom*>* atoms = fOutputFile->getJustInTimeAtomsFor(name);
- if ( atoms != NULL ) {
- this->addAtoms(*atoms);
- //fprintf(stderr, "addJustInTimeAtoms(%s) => found in file %s\n", name, fOutputFile->getPath() );
- return atoms; // found a definition, no need to search anymore
- }
- }
-
- // give readers a chance
- for (std::vector<class ObjectFile::Reader*>::iterator it=fInputFiles.begin(); it != fInputFiles.end(); it++) {
- ObjectFile::Reader* reader = *it;
- if ( reader != NULL ) {
- // if this reader is a static archive that has the symbol we need, pull in all atoms in that module
- // if this reader is a dylib that exports the symbol we need, have it synthesize an atom for us.
- //fprintf(stderr, "addJustInTimeAtoms(%s), looking in reader %s\n", name, reader->getPath() );
- bool isDylibReader = (reader->getInstallPath() != NULL);
- if ( isDylibReader ? searchDylibs : searchArchives ) {
- std::vector<class ObjectFile::Atom*>* atoms = reader->getJustInTimeAtomsFor(name);
- if ( atoms != NULL ) {
- this->addAtoms(*atoms);
- //fprintf(stderr, "addJustInTimeAtoms(%s) => found in file %s\n", name, reader->getPath() );
- if ( !isDylibReader && fOptions.readerOptions().fTraceArchives ) {
- logArchive(reader);
- }
- // if this is a weak definition in a dylib
- if ( isDylibReader && (atoms->size() == 1) && (atoms->at(0)->getDefinitionKind() == ObjectFile::Atom::kExternalWeakDefinition) ) {
- // keep looking for a non-weak definition
- }
- else {
- // found a definition, no need to search anymore
- return atoms;
- }
- }
- }
- }
- }
-
- // for two level namesapce, give all implicitly link dylibs a chance
- if ( fOptions.nameSpace() == Options::kTwoLevelNameSpace ) {
- for (InstallNameToReader::iterator it=fDylibMap.begin(); it != fDylibMap.end(); it++) {
- if ( it->second->implicitlyLinked() ) {
- //fprintf(stderr, "addJustInTimeAtoms(%s), looking in implicitly linked %s\n", name, it->second->getPath() );
- std::vector<class ObjectFile::Atom*>* atoms = it->second->getJustInTimeAtomsFor(name);
- if ( atoms != NULL ) {
- this->addAtoms(*atoms);
- //fprintf(stderr, "addJustInTimeAtoms(%s) => found in file %s\n", name, reader->getPath() );
- // if this is a weak definition in a dylib
- if ( (atoms->size() == 1) && (atoms->at(0)->getDefinitionKind() == ObjectFile::Atom::kExternalWeakDefinition) ) {
- // keep looking for a non-weak definition
- }
- else {
- // found a definition, no need to search anymore
- return atoms;
- }
- }
- }
- }
- }
-
- // for flat namespace, give indirect dylibs
- if ( fOptions.nameSpace() != Options::kTwoLevelNameSpace ) {
- for (InstallNameToReader::iterator it=fDylibMap.begin(); it != fDylibMap.end(); it++) {
- if ( ! it->second->explicitlyLinked() ) {
- std::vector<class ObjectFile::Atom*>* atoms = it->second->getJustInTimeAtomsFor(name);
- if ( atoms != NULL ) {
- this->addAtoms(*atoms);
- //fprintf(stderr, "addJustInTimeAtoms(%s) => found in file %s\n", name, reader->getPath() );
- return atoms; // found a definition, no need to search anymore
- }
- }
- }
- }
-
- // writer creates a proxy in two cases:
- // 1) ld -r is being used to create a .o file
- // 2) -undefined dynamic_lookup is being used
- // 3) -U _foo is being used
- // 4) x86_64 kext bundle is being created
- if ( (fOptions.outputKind() == Options::kObjectFile)
- || ((fOptions.undefinedTreatment() != Options::kUndefinedError) && okToMakeProxy)
- || (fOptions.someAllowedUndefines() && okToMakeProxy)
- || (fOptions.outputKind() == Options::kKextBundle) ) {
- ObjectFile::Atom* atom = fOutputFile->getUndefinedProxyAtom(name);
- if ( atom != NULL ) {
- this->addAtom(*atom);
- return NULL;
- }
- }
- //fprintf(stderr, "addJustInTimeAtoms(%s) => not found\n", name);
- return NULL;
-}
-
-void Linker::resolve(ObjectFile::Reference* reference)
-{
- // look in global symbol table
- const char* targetName = reference->getTargetName();
- ObjectFile::Atom* target = fGlobalSymbolTable.find(targetName);
- if ( target == NULL ) {
- throwf("unexpected undefined symbol: %s", targetName);
- }
- reference->setTarget(*target, reference->getTargetOffset());
-}
-
-void Linker::resolveFrom(ObjectFile::Reference* reference)
-{
- // handle references that have two (from and to) targets
- const char* fromTargetName = reference->getFromTargetName();
- ObjectFile::Atom* fromTarget = fGlobalSymbolTable.find(fromTargetName);
- if ( fromTarget == NULL ) {
- throwf("unexpected undefined symbol: %s", fromTargetName);
- }
- reference->setFromTarget(*fromTarget);
-}
-
-
-void Linker::resolveReferences()
-{
- // note: the atom list may grow during this loop as libraries supply needed atoms
- for (unsigned int j=0; j < fAllAtoms.size(); ++j) {
- ObjectFile::Atom* atom = fAllAtoms[j];
- std::vector<class ObjectFile::Reference*>& references = atom->getReferences();
- for (std::vector<ObjectFile::Reference*>::iterator it=references.begin(); it != references.end(); it++) {
- ObjectFile::Reference* reference = *it;
- if ( reference->getTargetBinding() == ObjectFile::Reference::kUnboundByName )
- this->resolve(reference);
- if ( reference->getFromTargetBinding() == ObjectFile::Reference::kUnboundByName )
- this->resolveFrom(reference);
- }
- }
-}
-
-
-// used to remove stabs associated with atoms that won't be in output file
-class NotInSet
-{
-public:
- NotInSet(std::set<ObjectFile::Atom*>& theSet) : fSet(theSet) {}
-
- bool operator()(const ObjectFile::Reader::Stab& stab) const {
- if ( stab.atom == NULL )
- return false; // leave stabs that are not associated with any atome
- else
- return ( fSet.count(stab.atom) == 0 );
- }
-
-private:
- std::set<ObjectFile::Atom*>& fSet;
-};
-
-
-class NotLive
-{
-public:
- NotLive(std::set<ObjectFile::Atom*>& set) : fLiveAtoms(set) {}
-
- bool operator()(ObjectFile::Atom*& atom) const {
- //if ( fLiveAtoms.count(atom) == 0 )
- // fprintf(stderr, "dead strip %s\n", atom->getDisplayName());
- return ( fLiveAtoms.count(atom) == 0 );
- }
-private:
- std::set<ObjectFile::Atom*>& fLiveAtoms;
-};
-
-
-void Linker::addJustInTimeAtomsAndMarkLive(const char* name)
-{
- //fprintf(stderr, "addJustInTimeAtomsAndMarkLive(%s)\n", name);
- std::vector<class ObjectFile::Atom*>* atoms = this->addJustInTimeAtoms(name, true, true, true);
- if ( atoms != NULL ) {
- if ( fOptions.allGlobalsAreDeadStripRoots() ) {
- for (std::vector<ObjectFile::Atom*>::iterator it=atoms->begin(); it != atoms->end(); it++) {
- ObjectFile::Atom* atom = *it;
- if ( atom->getScope() == ObjectFile::Atom::scopeGlobal ) {
- WhyLiveBackChain rootChain;
- rootChain.previous = NULL;
- rootChain.referer = atom;
- this->markLive(*atom, &rootChain);
- }
- }
- }
- delete atoms;
- }
-}
-
-void Linker::markLive(ObjectFile::Atom& atom, struct Linker::WhyLiveBackChain* previous)
-{
- //fprintf(stderr, "markLive(%p)\n", &atom);
- if ( fLiveAtoms.count(&atom) == 0 ) {
- // if -why_live cares about this symbol, then dump chain
- if ( (previous->referer != NULL) && fOptions.printWhyLive(previous->referer->getDisplayName()) ) {
- int depth = 0;
- for(WhyLiveBackChain* p = previous; p != NULL; p = p->previous, ++depth) {
- for(int i=depth; i > 0; --i)
- fprintf(stderr, " ");
- fprintf(stderr, "%p %s from %s\n", p->referer, p->referer->getDisplayName(), p->referer->getFile()->getPath());
- }
- }
- // set up next chain
- WhyLiveBackChain thisChain;
- thisChain.previous = previous;
- // this atom is live
- fLiveAtoms.insert(&atom);
- // update total size info (except for __ZEROPAGE atom)
- if ( atom.getSegment().isContentReadable() ) {
- fTotalSize += atom.getSize();
- if ( atom.isZeroFill() )
- fTotalZeroFillSize += atom.getSize();
- }
- // and all atoms it references
- std::vector<class ObjectFile::Reference*>& references = atom.getReferences();
- for (std::vector<ObjectFile::Reference*>::iterator it=references.begin(); it != references.end(); it++) {
- ObjectFile::Reference* reference = *it;
- if ( reference->getTargetBinding() == ObjectFile::Reference::kUnboundByName ) {
- // look in global symbol table
- const char* targetName = reference->getTargetName();
- ObjectFile::Atom* target = fGlobalSymbolTable.find(targetName);
- if ( (target == NULL) || (target->getDefinitionKind() == ObjectFile::Atom::kTentativeDefinition) ) {
- // load archives or dylibs
- this->addJustInTimeAtomsAndMarkLive(targetName);
- }
- // look again
- target = fGlobalSymbolTable.find(targetName);
- if ( target != NULL ) {
- reference->setTarget(*target, reference->getTargetOffset());
- }
- else {
- // mark as undefined, for later error processing
- fAtomsWithUnresolvedReferences.push_back(&atom);
- fGlobalSymbolTable.require(targetName);
- }
- }
- switch ( reference->getTargetBinding() ) {
- case ObjectFile::Reference::kBoundDirectly:
- case ObjectFile::Reference::kBoundByName:
- thisChain.referer = &reference->getTarget();
- markLive(reference->getTarget(), &thisChain);
- break;
- case ObjectFile::Reference::kDontBind:
- case ObjectFile::Reference::kUnboundByName:
- // do nothing
- break;
- }
- // do the same as above, for "from target"
- if ( reference->getFromTargetBinding() == ObjectFile::Reference::kUnboundByName ) {
- // look in global symbol table
- const char* targetName = reference->getFromTargetName();
- ObjectFile::Atom* target = fGlobalSymbolTable.find(targetName);
- if ( (target == NULL) || (target->getDefinitionKind() == ObjectFile::Atom::kTentativeDefinition) ) {
- // load archives or dylibs
- this->addJustInTimeAtomsAndMarkLive(targetName);
- }
- // look again
- target = fGlobalSymbolTable.find(targetName);
- if ( target != NULL ) {
- reference->setFromTarget(*target);
- }
- else {
- // mark as undefined, for later error processing
- fGlobalSymbolTable.require(targetName);
- }
- }
- switch ( reference->getFromTargetBinding() ) {
- case ObjectFile::Reference::kBoundDirectly:
- case ObjectFile::Reference::kBoundByName:
- thisChain.referer = &reference->getFromTarget();
- markLive(reference->getFromTarget(), &thisChain);
- break;
- case ObjectFile::Reference::kUnboundByName:
- case ObjectFile::Reference::kDontBind:
- // do nothing
- break;
- }
- }
- }
-}
-
-
-void Linker::addLiveRoot(const char* name)
-{
- ObjectFile::Atom* target = fGlobalSymbolTable.find(name);
- if ( target == NULL ) {
- this->addJustInTimeAtomsAndMarkLive(name);
- target = fGlobalSymbolTable.find(name);
- }
- if ( target != NULL )
- fLiveRootAtoms.insert(target);
-}
-
-void Linker::moveToFrontOfSection(ObjectFile::Atom* atom)
-{
- // check if already moved to front
- if ( fInitializerAtoms.find(atom) == fInitializerAtoms.end() ) {
- // don't re-order initializers from .o files without MH_SUBSECTIONS_VIA_SYMBOLS
- // since that could make all atoms in the file look like initializers
- if ( atom->getFile()->canScatterAtoms() ) {
- //fprintf(stdout, "marking as initializer: %s\n", atom->getDisplayName());
- fInitializerAtoms.insert(atom);
- // mark all functions that this function references
- std::vector<class ObjectFile::Reference*>& references = atom->getReferences();
- for (std::vector<ObjectFile::Reference*>::const_iterator rit=references.begin(); rit != references.end(); rit++) {
- ObjectFile::Atom* childAtom = &((*rit)->getTarget());
- if ( childAtom != NULL ) {
- if ( (*rit)->isBranch() ) {
- this->moveToFrontOfSection(childAtom);
- }
- else if ( (childAtom->getName() != NULL) && (strncmp(childAtom->getName(), "___tcf_", 7) == 0) ) {
- //fprintf(stdout, "marking as terminator: %s\n", childAtom->getDisplayName());
- fTerminatorAtoms.insert(childAtom);
- }
- }
- }
- }
- }
-}
-
-void Linker::deadStripResolve()
-{
- // add main() to live roots
- ObjectFile::Atom* entryPoint = this->entryPoint(false, true);
- if ( entryPoint != NULL )
- fLiveRootAtoms.insert(entryPoint);
-
- // add dyld_stub_binding_helper/dyld_stub_binder to live roots
- ObjectFile::Atom* dyldHelper = this->dyldClassicHelper();
- if ( dyldHelper != NULL )
- fLiveRootAtoms.insert(dyldHelper);
- dyldHelper = this->dyldCompressedHelper();
- if ( dyldHelper != NULL )
- fLiveRootAtoms.insert(dyldHelper);
-
- // if using lazy dylib loading, add dyld_lazy_dylib_stub_binding_helper() to live roots
- if ( fOptions.usingLazyDylibLinking() ) {
- ObjectFile::Atom* dyldLazyDylibHelper = this->dyldLazyLibraryHelper();
- if ( dyldLazyDylibHelper != NULL )
- fLiveRootAtoms.insert(dyldLazyDylibHelper);
- }
-
- // add -exported_symbols_list, -init, and -u entries to live roots
- std::vector<const char*>& initialUndefines = fOptions.initialUndefines();
- for (std::vector<const char*>::iterator it=initialUndefines.begin(); it != initialUndefines.end(); it++)
- addLiveRoot(*it);
-
- // if -exported_symbols_list that has wildcards, we need to find all matches and make them the roots
- // <rdar://problem/5524973>
- if ( fOptions.hasWildCardExportRestrictList() ) {
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- ObjectFile::Atom* atom = *it;
- if ( (atom->getScope() == ObjectFile::Atom::scopeGlobal)
- && (fDeadAtoms.count(atom) == 0)
- && fOptions.shouldExport(atom->getName()) )
- fLiveRootAtoms.insert(atom);
- }
- }
-
- // in some cases, every global scope atom in initial .o files is a root
- if ( fOptions.allGlobalsAreDeadStripRoots() ) {
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- ObjectFile::Atom* atom = *it;
- if ( (atom->getScope() == ObjectFile::Atom::scopeGlobal) && (fDeadAtoms.count(atom) == 0) )
- fLiveRootAtoms.insert(atom);
- }
- }
-
- // mark all roots as live, and all atoms they reference
- for (std::set<ObjectFile::Atom*>::iterator it=fLiveRootAtoms.begin(); it != fLiveRootAtoms.end(); it++) {
- WhyLiveBackChain rootChain;
- rootChain.previous = NULL;
- rootChain.referer = *it;
- markLive(**it, &rootChain);
- }
-
- // it is possible that there are unresolved references that can be resolved now
- // this can happen if the first reference to a common symbol in an archive.
- // common symbols are not in the archive TOC, but the .o could have been pulled in later.
- // <rdar://problem/4654131> ld64 while linking cc1 [ when dead_strip is ON]
- for (std::vector<ObjectFile::Atom*>::iterator it=fAtomsWithUnresolvedReferences.begin(); it != fAtomsWithUnresolvedReferences.end(); it++) {
- std::vector<class ObjectFile::Reference*>& references = (*it)->getReferences();
- for (std::vector<ObjectFile::Reference*>::iterator rit=references.begin(); rit != references.end(); rit++) {
- ObjectFile::Reference* reference = *rit;
- if ( reference->getTargetBinding() == ObjectFile::Reference::kUnboundByName ) {
- ObjectFile::Atom* target = fGlobalSymbolTable.find(reference->getTargetName());
- if ( target != NULL ) {
- reference->setTarget(*target, reference->getTargetOffset());
- fLiveAtoms.insert(target);
- // by just adding this atom to fLiveAtoms set, we are assuming it has no
- // references, which is true for commons.
- if ( target->getDefinitionKind() != ObjectFile::Atom::kTentativeDefinition )
- warning("internal error %s is not a tentative definition", target->getDisplayName());
- }
- }
- if ( reference->getFromTargetBinding() == ObjectFile::Reference::kUnboundByName ) {
- ObjectFile::Atom* target = fGlobalSymbolTable.find(reference->getFromTargetName());
- if ( target != NULL ) {
- reference->setFromTarget(*target);
- fLiveAtoms.insert(target);
- // by just adding this atom to fLiveAtoms set, we are assuming it has no
- // references, which is true for commons.
- if ( target->getDefinitionKind() != ObjectFile::Atom::kTentativeDefinition )
- warning("internal error %s is not a tentative definition", target->getDisplayName());
- }
- }
- }
- }
-
- // It is possible that some weak symbols were overridden by lazily load objects from archives
- // and we have some atoms that still refer to the overridden ones.
- // In that case we need to go back and rebind
- if ( fAtomsOverriddenByLateLoads.size() > 0 ) {
- for (std::set<ObjectFile::Atom*>::iterator it=fLiveAtoms.begin(); it != fLiveAtoms.end(); ++it) {
- ObjectFile::Atom* atom = *it;
- std::vector<class ObjectFile::Reference*>& references = atom->getReferences();
- for (std::vector<ObjectFile::Reference*>::iterator rit=references.begin(); rit != references.end(); ++rit) {
- ObjectFile::Reference* reference = *rit;
- ObjectFile::Atom* toTarget = &reference->getTarget();
- if ( fAtomsOverriddenByLateLoads.count(toTarget) ) {
- //fprintf(stderr, "change reference in %p from %p to %p\n", atom, toTarget, fGlobalSymbolTable.find(toTarget->getName()));
- reference->setTarget(*fGlobalSymbolTable.find(toTarget->getName()), reference->getTargetOffset());
- }
- ObjectFile::Atom* fromTarget = &reference->getFromTarget();
- if ( (fromTarget != NULL) && fAtomsOverriddenByLateLoads.count(fromTarget) ) {
- //fprintf(stderr, "change from reference in %p from %p to %p\n", atom, fromTarget, fGlobalSymbolTable.find(fromTarget->getName()));
- reference->setTarget(*fGlobalSymbolTable.find(fromTarget->getName()), reference->getFromTargetOffset());
- }
- }
- }
-
- // make sure overriders are live if the atom they overrid was live
- for (std::set<ObjectFile::Atom*>::iterator it=fAtomsOverriddenByLateLoads.begin(); it != fAtomsOverriddenByLateLoads.end(); ++it) {
- ObjectFile::Atom* overriderAtom = *it;
- if ( fLiveAtoms.count(overriderAtom) ) {
- WhyLiveBackChain rootChain;
- rootChain.previous = NULL;
- rootChain.referer = *it;
- markLive(*fGlobalSymbolTable.find(overriderAtom->getName()), &rootChain);
- }
- }
-
- // remove overridden atoms from fLiveAtoms
- fAllAtoms.erase(std::remove_if(fAllAtoms.begin(), fAllAtoms.end(), InSet(fAtomsOverriddenByLateLoads)), fAllAtoms.end());
- fAtomsOverriddenByLateLoads.clear();
- // remove dead atoms from fLiveAtoms
- fAllAtoms.erase(std::remove_if(fAllAtoms.begin(), fAllAtoms.end(), InSet(fDeadAtoms)), fAllAtoms.end());
- }
-
- // now remove all non-live atoms from fAllAtoms
- fAllAtoms.erase(std::remove_if(fAllAtoms.begin(), fAllAtoms.end(), NotLive(fLiveAtoms)), fAllAtoms.end());
-}
-
-void Linker::checkObjC()
-{
- // check dylibs
- switch ( fCurrentObjCConstraint ) {
- case ObjectFile::Reader::kObjcNone:
- // can link against any dylib
- break;
- case ObjectFile::Reader::kObjcRetainRelease:
- // cannot link against GC-only dylibs
- for (InstallNameToReader::iterator it=fDylibMap.begin(); it != fDylibMap.end(); it++) {
- if ( it->second->explicitlyLinked() ) {
- if ( it->second->getObjCConstraint() == ObjectFile::Reader::kObjcGC )
- throwf("this linkage unit uses Retain/Release. It cannot link against the GC-only dylib: %s", it->second->getPath());
- }
- }
- break;
- case ObjectFile::Reader::kObjcRetainReleaseOrGC:
- // can link against GC or RR dylibs
- break;
- case ObjectFile::Reader::kObjcGC:
- // cannot link against RR-only dylibs
- for (InstallNameToReader::iterator it=fDylibMap.begin(); it != fDylibMap.end(); it++) {
- if ( it->second->explicitlyLinked() ) {
- if ( it->second->getObjCConstraint() == ObjectFile::Reader::kObjcRetainRelease )
- throwf("this linkage unit requires GC. It cannot link against Retain/Release dylib: %s", it->second->getPath());
- }
- }
- break;
- }
-
- // synthesize __OBJC __image_info atom if needed
- if ( fCurrentObjCConstraint != ObjectFile::Reader::kObjcNone ) {
- this->addAtom(fOutputFile->makeObjcInfoAtom(fCurrentObjCConstraint, fObjcReplacmentClasses));
- }
-}
-
-
-static uint8_t pcRelKind(cpu_type_t arch)
-{
- switch ( arch ) {
- case CPU_TYPE_POWERPC:
- return ppc::kPointerDiff32;
- case CPU_TYPE_POWERPC64:
- return ppc64::kPointerDiff32;
- case CPU_TYPE_I386:
- return x86::kPointerDiff;
- case CPU_TYPE_X86_64:
- return x86_64::kPointerDiff32;
- case CPU_TYPE_ARM:
- return arm::kPointerDiff;
- }
- throw "uknown architecture";
-}
-
-typedef uint8_t* (*oldcreatedof_func_t) (const char*, cpu_type_t, unsigned int, const char*[], const char*[], uint64_t offsetsInDOF[], size_t* size);
-typedef uint8_t* (*createdof_func_t)(cpu_type_t, unsigned int, const char*[], unsigned int, const char*[], const char*[], uint64_t offsetsInDOF[], size_t* size);
-
-
-void Linker::processDTrace()
-{
- // only make __dof section in final linked images
- if ( fOptions.outputKind() == Options::kObjectFile )
- return;
-
- // scan all atoms looking for dtrace probes
- std::vector<DTraceProbeInfo> probeSites;
- std::vector<DTraceProbeInfo> isEnabledSites;
- std::map<const ObjectFile::Atom*,CStringSet> atomToDtraceTypes;
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); ++it) {
- ObjectFile::Atom* atom = *it;
- std::vector<class ObjectFile::Reference*>& references = atom->getReferences();
- for (std::vector<ObjectFile::Reference*>::iterator rit=references.begin(); rit != references.end(); ++rit) {
- ObjectFile::Reference* ref = *rit;
- if ( ref->getTargetBinding() == ObjectFile::Reference::kDontBind ) {
- const char* probeName = ref->getTargetName();
- if ( probeName != NULL ) {
- uint32_t offsetInAtom = ref->getFixUpOffset();
- if ( strncmp(probeName, "___dtrace_probe$", 16) == 0 )
- probeSites.push_back(DTraceProbeInfo(atom, offsetInAtom, probeName));
- else if ( strncmp(probeName, "___dtrace_isenabled$", 20) == 0 )
- isEnabledSites.push_back(DTraceProbeInfo(atom, offsetInAtom, probeName));
- else if ( strncmp(probeName, "___dtrace_", 10) == 0 )
- atomToDtraceTypes[atom].insert(probeName);
- }
- }
- }
- }
-
- // if no probes, we're done
- if ( (probeSites.size() == 0) && (isEnabledSites.size() == 0) )
- return;
-
- // partition probes by provider name
- // The symbol names looks like:
- // "___dtrace_probe$" provider-name "$" probe-name [ "$"... ]
- // "___dtrace_isenabled$" provider-name "$" probe-name [ "$"... ]
- ProviderToProbes providerToProbes;
- std::vector<DTraceProbeInfo> emptyList;
- for(std::vector<DTraceProbeInfo>::iterator it = probeSites.begin(); it != probeSites.end(); ++it) {
- // ignore probes in functions that were coalesed away rdar://problem/5628149
- if ( fDeadAtoms.count((ObjectFile::Atom*)(it->atom)) == 0 ) {
- const char* providerStart = &it->probeName[16];
- const char* providerEnd = strchr(providerStart, '$');
- if ( providerEnd != NULL ) {
- char providerName[providerEnd-providerStart+1];
- strlcpy(providerName, providerStart, providerEnd-providerStart+1);
- ProviderToProbes::iterator pos = providerToProbes.find(providerName);
- if ( pos == providerToProbes.end() ) {
- const char* dup = strdup(providerName);
- providerToProbes[dup] = emptyList;
- }
- providerToProbes[providerName].push_back(*it);
- }
- }
- }
- for(std::vector<DTraceProbeInfo>::iterator it = isEnabledSites.begin(); it != isEnabledSites.end(); ++it) {
- // ignore probes in functions that were coalesed away rdar://problem/5628149
- if ( fDeadAtoms.count((ObjectFile::Atom*)(it->atom)) == 0 ) {
- const char* providerStart = &it->probeName[20];
- const char* providerEnd = strchr(providerStart, '$');
- if ( providerEnd != NULL ) {
- char providerName[providerEnd-providerStart+1];
- strlcpy(providerName, providerStart, providerEnd-providerStart+1);
- ProviderToProbes::iterator pos = providerToProbes.find(providerName);
- if ( pos == providerToProbes.end() ) {
- const char* dup = strdup(providerName);
- providerToProbes[dup] = emptyList;
- }
- providerToProbes[providerName].push_back(*it);
- }
- }
- }
-
- // create a DOF section for each provider
- int dofIndex=1;
- CStringSet sectionNamesUsed;
- for(ProviderToProbes::iterator pit = providerToProbes.begin(); pit != providerToProbes.end(); ++pit, ++dofIndex) {
- const char* providerName = pit->first;
- const std::vector<DTraceProbeInfo>& probes = pit->second;
-
- // open library and find dtrace_create_dof()
- void* handle = dlopen("/usr/lib/libdtrace.dylib", RTLD_LAZY);
- if ( handle == NULL )
- throwf("couldn't dlopen() /usr/lib/libdtrace.dylib: %s", dlerror());
- createdof_func_t pCreateDOF = (createdof_func_t)dlsym(handle, "dtrace_ld_create_dof");
- if ( pCreateDOF == NULL )
- throwf("couldn't find \"dtrace_ld_create_dof\" in /usr/lib/libdtrace.dylib: %s", dlerror());
- // build list of typedefs/stability infos for this provider
- CStringSet types;
- for(std::vector<DTraceProbeInfo>::const_iterator it = probes.begin(); it != probes.end(); ++it) {
- std::map<const ObjectFile::Atom*,CStringSet>::iterator pos = atomToDtraceTypes.find(it->atom);
- if ( pos != atomToDtraceTypes.end() ) {
- for(CStringSet::iterator sit = pos->second.begin(); sit != pos->second.end(); ++sit) {
- const char* providerStart = strchr(*sit, '$')+1;
- const char* providerEnd = strchr(providerStart, '$');
- if ( providerEnd != NULL ) {
- char aProviderName[providerEnd-providerStart+1];
- strlcpy(aProviderName, providerStart, providerEnd-providerStart+1);
- if ( strcmp(aProviderName, providerName) == 0 )
- types.insert(*sit);
- }
- }
- }
- }
- int typeCount = types.size();
- const char* typeNames[typeCount];
- //fprintf(stderr, "types for %s:\n", providerName);
- uint32_t index = 0;
- for(CStringSet::iterator it = types.begin(); it != types.end(); ++it) {
- typeNames[index] = *it;
- //fprintf(stderr, "\t%s\n", *it);
- ++index;
- }
-
- // build list of probe/isenabled sites
- const uint32_t probeCount = probes.size();
- const char* probeNames[probeCount];
- const char* funtionNames[probeCount];
- uint64_t offsetsInDOF[probeCount];
- index = 0;
- for(std::vector<DTraceProbeInfo>::const_iterator it = probes.begin(); it != probes.end(); ++it) {
- probeNames[index] = it->probeName;
- funtionNames[index] = it->atom->getName();
- offsetsInDOF[index] = 0;
- ++index;
- }
- //fprintf(stderr, "calling libtrace to create DOF\n");
- //for(uint32_t i=0; i < probeCount; ++i)
- // fprintf(stderr, " [%u]\t %s\t%s\n", i, probeNames[i], funtionNames[i]);
- // call dtrace library to create DOF section
- size_t dofSectionSize;
- uint8_t* p = (*pCreateDOF)(fArchitecture, typeCount, typeNames, probeCount, probeNames, funtionNames, offsetsInDOF, &dofSectionSize);
- if ( p != NULL ) {
- char sectionName[18];
- strcpy(sectionName, "__dof_");
- strlcpy(§ionName[6], providerName, 10);
- // create unique section name so each DOF is in its own section
- if ( sectionNamesUsed.count(sectionName) != 0 ) {
- sectionName[15] = '0';
- sectionName[16] = '\0';
- while ( sectionNamesUsed.count(sectionName) != 0 )
- ++sectionName[15];
- }
- sectionNamesUsed.insert(sectionName);
- char symbolName[strlen(providerName)+64];
- sprintf(symbolName, "__dtrace_dof_for_provider_%s", providerName);
- opaque_section::Reader* reader = new opaque_section::Reader("__TEXT", sectionName,
- "dtrace", p, dofSectionSize, fNextInputOrdinal, symbolName);
- fNextInputOrdinal += dofSectionSize;
- // add references
- for (uint32_t i=0; i < probeCount; ++i) {
- uint64_t offset = offsetsInDOF[i];
- //fprintf(stderr, "%s offset[%d]=0x%08llX\n", providerName, i, offset);
- if ( offset > dofSectionSize )
- throwf("offsetsInDOF[%d]=%0llX > dofSectionSize=%0lX\n", i, offset, dofSectionSize);
- reader->addSectionReference(pcRelKind(fArchitecture), offset, probes[i].atom, probes[i].offset, reader->getAtoms()[0], 0);
- }
- this->addAtoms(reader->getAtoms());
- }
- else {
- throw "error creating dtrace DOF section";
- }
- }
-}
-
-
-static bool matchesObjectFile(ObjectFile::Atom* atom, const char* objectFileLeafName)
-{
- if ( objectFileLeafName == NULL )
- return true;
- const char* atomFullPath = atom->getFile()->getPath();
- const char* lastSlash = strrchr(atomFullPath, '/');
- if ( lastSlash != NULL ) {
- if ( strcmp(&lastSlash[1], objectFileLeafName) == 0 )
- return true;
- }
- else {
- if ( strcmp(atomFullPath, objectFileLeafName) == 0 )
- return true;
- }
- return false;
-}
-
-
-static bool usesAnonymousNamespace(const char* symbol)
-{
- return ( (strncmp(symbol, "__Z", 3) == 0) && (strstr(symbol, "_GLOBAL__N_") != NULL) );
-}
-
-
-//
-// convert:
-// __ZN20_GLOBAL__N__Z5main2v3barEv => _ZN-3barEv
-// __ZN37_GLOBAL__N_main.cxx_00000000_493A01A33barEv => _ZN-3barEv
-//
-static void canonicalizeAnonymousName(const char* inSymbol, char outSymbol[])
-{
- const char* globPtr = strstr(inSymbol, "_GLOBAL__N_");
- while ( isdigit(*(--globPtr)) )
- ; // loop
- char* endptr;
- unsigned long length = strtoul(globPtr+1, &endptr, 10);
- const char* globEndPtr = endptr + length;
- int startLen = globPtr-inSymbol+1;
- memcpy(outSymbol, inSymbol, startLen);
- outSymbol[startLen] = '-';
- strcpy(&outSymbol[startLen+1], globEndPtr);
-}
-
-
-ObjectFile::Atom* Linker::findAtom(const Options::OrderedSymbol& orderedSymbol)
-{
- ObjectFile::Atom* atom = fGlobalSymbolTable.find(orderedSymbol.symbolName);
- if ( atom != NULL ) {
- if ( matchesObjectFile(atom, orderedSymbol.objectFileName) )
- return atom;
- }
- else {
- // slow case. The requested symbol is not in symbol table, so might be static function
- static SymbolTable::Mapper hashTableOfTranslationUnitScopedSymbols;
- static SymbolTable::Mapper hashTableOfSymbolsWithAnonymousNamespace;
- static bool built = false;
- // build a hash_map the first time
- if ( !built ) {
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- atom = *it;
- const char* name = atom->getName();
- if ( name != NULL) {
- if ( usesAnonymousNamespace(name) ) {
- // symbol that uses anonymous namespace
- char canonicalName[strlen(name)+2];
- canonicalizeAnonymousName(name, canonicalName);
- const char* hashName = strdup(canonicalName);
- SymbolTable::Mapper::iterator pos = hashTableOfSymbolsWithAnonymousNamespace.find(hashName);
- if ( pos == hashTableOfSymbolsWithAnonymousNamespace.end() )
- hashTableOfSymbolsWithAnonymousNamespace[hashName] = atom;
- else
- hashTableOfSymbolsWithAnonymousNamespace[hashName] = NULL; // collision, denote with NULL
- }
- else if ( atom->getScope() == ObjectFile::Atom::scopeTranslationUnit ) {
- // static function or data
- SymbolTable::Mapper::iterator pos = hashTableOfTranslationUnitScopedSymbols.find(name);
- if ( pos == hashTableOfTranslationUnitScopedSymbols.end() )
- hashTableOfTranslationUnitScopedSymbols[name] = atom;
- else
- hashTableOfTranslationUnitScopedSymbols[name] = NULL; // collision, denote with NULL
- }
- }
- }
- //fprintf(stderr, "built hash table of %lu static functions\n", hashTableOfTranslationUnitScopedSymbols.size());
- built = true;
- }
-
- // look for name in hashTableOfTranslationUnitScopedSymbols
- SymbolTable::Mapper::iterator pos = hashTableOfTranslationUnitScopedSymbols.find(orderedSymbol.symbolName);
- if ( pos != hashTableOfTranslationUnitScopedSymbols.end() ) {
- if ( (pos->second != NULL) && matchesObjectFile(pos->second, orderedSymbol.objectFileName) ) {
- //fprintf(stderr, "found %s in hash table\n", orderedSymbol.symbolName);
- return pos->second;
- }
- if ( pos->second == NULL )
- // name is in hash table, but atom is NULL, so that means there are duplicates, so we use super slow way
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- atom = *it;
- if ( atom->getScope() == ObjectFile::Atom::scopeTranslationUnit ) {
- const char* name = atom->getName();
- if ( (name != NULL) && (strcmp(name, orderedSymbol.symbolName) == 0) ) {
- if ( matchesObjectFile(atom, orderedSymbol.objectFileName) ) {
- if ( fOptions.printOrderFileStatistics() )
- warning("%s specified in order_file but it exists in multiple .o files. "
- "Prefix symbol with .o filename in order_file to disambiguate", orderedSymbol.symbolName);
- return atom;
- }
- }
- }
- }
- }
-
- // look for name in hashTableOfSymbolsWithAnonymousNamespace
- if ( usesAnonymousNamespace(orderedSymbol.symbolName) ) {
- // symbol that uses anonymous namespace
- char canonicalName[strlen(orderedSymbol.symbolName)+2];
- canonicalizeAnonymousName(orderedSymbol.symbolName, canonicalName);
- SymbolTable::Mapper::iterator pos = hashTableOfSymbolsWithAnonymousNamespace.find(canonicalName);
- if ( pos != hashTableOfSymbolsWithAnonymousNamespace.end() ) {
- if ( (pos->second != NULL) && matchesObjectFile(pos->second, orderedSymbol.objectFileName) ) {
- //fprintf(stderr, "found %s in anonymous namespace hash table\n", canonicalName);
- return pos->second;
- }
- if ( pos->second == NULL )
- // name is in hash table, but atom is NULL, so that means there are duplicates, so we use super slow way
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- atom = *it;
- const char* name = atom->getName();
- if ( (name != NULL) && usesAnonymousNamespace(name) ) {
- char canonicalAtomName[strlen(name)+2];
- canonicalizeAnonymousName(name, canonicalAtomName);
- if ( strcmp(canonicalAtomName, canonicalName) == 0 ) {
- if ( matchesObjectFile(atom, orderedSymbol.objectFileName) ) {
- if ( fOptions.printOrderFileStatistics() )
- warning("%s specified in order_file but it exists in multiple .o files. "
- "Prefix symbol with .o filename in order_file to disambiguate", orderedSymbol.symbolName);
- return atom;
- }
- }
- }
- }
- }
- }
- }
- return NULL;
-}
-
-
-void Linker::sortSections()
-{
- Section::assignIndexes();
-}
-
-
-//
-// Linker::sortAtoms()
-//
-// The purpose of this method is to take the graph of all Atoms and produce an ordered
-// sequence of atoms. The constraints are that: 1) all Atoms of the same Segment must
-// be contiguous, 2) all Atoms of the same Section must be contigous, 3) Atoms specified
-// in an order_file are seqenced as in the order_file and before Atoms not specified,
-// 4) Atoms in the same section from the same .o file should be contiguous and sequenced
-// in the same order they were in the .o file, 5) Atoms in the same Section but which came
-// from different .o files should be sequenced in the same order that the .o files
-// were passed to the linker (i.e. command line order).
-//
-// The way this is implemented is that the linker passes a "base ordinal" to each Reader
-// as it is constructed. The reader should construct it Atoms so that calling getOrdinal()
-// on its atoms returns a contiguous range of values starting at the base ordinal. Then
-// sorting is just sorting by section, then by ordinal.
-//
-// If an order_file is specified, it gets more complicated. First, an override-ordinal map
-// is created. It causes the sort routine to ignore the value returned by getOrdinal() and
-// use the override value instead. Next some Atoms must be layed out consecutively
-// (e.g. hand written assembly that does not end with return, but rather falls into
-// the next label). This is modeled in Readers via a "kFollowOn" reference. The use of
-// kFollowOn refernces produces "clusters" of atoms that must stay together.
-// If an order_file tries to move one atom, it may need to move a whole cluster. The
-// algorithm to do this models clusters using two maps. The "starts" maps maps any
-// atom in a cluster to the first Atom in the cluster. The "nexts" maps an Atom in a
-// cluster to the next Atom in the cluster. With this in place, while processing an
-// order_file, if any entry is in a cluster (in "starts" map), then the entire cluster is
-// given ordinal overrides.
-//
-void Linker::sortAtoms()
-{
- fStartSortTime = mach_absolute_time();
- // if -order_file is used, build map of atom ordinal overrides
- std::map<const ObjectFile::Atom*, uint32_t>* ordinalOverrideMap = NULL;
- std::map<const ObjectFile::Atom*, uint32_t> theOrdinalOverrideMap;
- const bool log = false;
- if ( fOptions.orderedSymbols().size() != 0 ) {
- // first make a pass to find all follow-on references and build start/next maps
- // which are a way to represent clusters of atoms that must layout together
- std::map<const ObjectFile::Atom*, const ObjectFile::Atom*> followOnStarts;
- std::map<const ObjectFile::Atom*, const ObjectFile::Atom*> followOnNexts;
- for (std::vector<ObjectFile::Atom*>::iterator ait=fAllAtoms.begin(); ait != fAllAtoms.end(); ait++) {
- ObjectFile::Atom* atom = *ait;
- std::vector<class ObjectFile::Reference*>& references = atom->getReferences();
- for (std::vector<ObjectFile::Reference*>::iterator rit=references.begin(); rit != references.end(); rit++) {
- ObjectFile::Reference* ref = *rit;
- if ( ref->getKind() == 1 ) { // FIX FIX
- ObjectFile::Atom* targetAtom = &ref->getTarget();
- if ( log ) fprintf(stderr, "ref %s -> %s", atom->getDisplayName(), targetAtom->getDisplayName());
- std::map<const ObjectFile::Atom*, const ObjectFile::Atom*>::iterator startFrom = followOnStarts.find(atom);
- std::map<const ObjectFile::Atom*, const ObjectFile::Atom*>::iterator startTo = followOnStarts.find(targetAtom);
- if ( (startFrom == followOnStarts.end()) && (startTo == followOnStarts.end()) ) {
- // this is first time we've seen either atom, make simple cluster of the two
- if ( log ) fprintf(stderr, " new cluster\n");
- followOnStarts[atom] = atom;
- followOnStarts[targetAtom] = atom;
- followOnNexts[atom] = targetAtom;
- followOnNexts[targetAtom] = NULL;
- }
- else if ( (startFrom != followOnStarts.end()) && (startTo == followOnStarts.end()) && (followOnNexts[atom] == NULL) ) {
- // atom is at end of an existing cluster, so append target to end of cluster
- if ( log ) fprintf(stderr, " end of cluster starting with %s\n", followOnStarts[atom]->getDisplayName());
- followOnNexts[atom] = targetAtom;
- followOnNexts[targetAtom] = NULL;
- followOnStarts[targetAtom] = followOnStarts[atom];
- }
- else {
- // gerneral case of inserting into an existing cluster
- if ( followOnNexts[atom] != NULL ) {
- // an atom with two follow-ons is illegal
- warning("can't order %s because both %s and %s must follow it",
- atom->getDisplayName(), targetAtom->getDisplayName(), followOnNexts[atom]->getDisplayName());
- }
- else {
- // there already exists an atom that says target must be its follow-on
- const ObjectFile::Atom* originalStart = startTo->second;
- const ObjectFile::Atom* originalPrevious = originalStart;
- while ( followOnNexts[originalPrevious] != targetAtom )
- originalPrevious = followOnNexts[originalPrevious];
- bool otherIsAlias = (originalPrevious->getSize() == 0);
- bool thisIsAlias = (atom->getSize() == 0);
- if ( !otherIsAlias && !thisIsAlias ) {
- warning("can't order %s because both %s and %s must preceed it",
- targetAtom->getDisplayName(), originalPrevious->getDisplayName(), atom->getDisplayName());
- }
- else if ( otherIsAlias ) {
- if ( originalPrevious == originalStart ) {
- // other is alias at start of cluster, make this the new start of cluster
- if ( log ) fprintf(stderr, " becomes new start of cluster previous starting with %s\n", originalStart->getDisplayName());
- followOnNexts[atom] = originalPrevious;
- for(const ObjectFile::Atom* nextAtom = atom; nextAtom != NULL; nextAtom = followOnNexts[nextAtom])
- followOnStarts[nextAtom] = atom;
- }
- else {
- // other is alias in middle of cluster, insert new atom before it
- if ( log ) fprintf(stderr, " insert into cluster starting with %s before alias %s\n", originalStart->getDisplayName(), originalPrevious->getDisplayName());
- followOnStarts[atom] = originalStart;
- followOnNexts[atom] = originalPrevious;
- for(const ObjectFile::Atom* a = originalStart; a != NULL; a = followOnNexts[a]) {
- if ( followOnNexts[a] == originalPrevious ) {
- followOnNexts[a] = atom;
- break;
- }
- }
- }
- }
- else {
- // this is alias, so it can go inbetween originalPrevious and targetAtom
- if ( log ) fprintf(stderr, " insert into cluster starting with %s after %s\n", originalStart->getDisplayName(), originalPrevious->getDisplayName());
- followOnStarts[atom] = originalStart;
- followOnNexts[atom] = followOnNexts[originalPrevious];
- followOnNexts[originalPrevious] = atom;
- }
- }
- }
- }
- }
- }
-
- if ( log ) {
- for(std::map<const ObjectFile::Atom*, const ObjectFile::Atom*>::iterator it = followOnStarts.begin(); it != followOnStarts.end(); ++it)
- fprintf(stderr, "start %s -> %s\n", it->first->getDisplayName(), it->second->getDisplayName());
-
- for(std::map<const ObjectFile::Atom*, const ObjectFile::Atom*>::iterator it = followOnNexts.begin(); it != followOnNexts.end(); ++it)
- fprintf(stderr, "next %s -> %s\n", it->first->getDisplayName(), (it->second != NULL) ? it->second->getDisplayName() : "null");
- }
-
- // with the start/next maps of follow-on atoms we can process the order file and produce override ordinals
- ordinalOverrideMap = &theOrdinalOverrideMap;
- uint32_t index = 0;
- uint32_t matchCount = 0;
- std::vector<Options::OrderedSymbol>& orderedSymbols = fOptions.orderedSymbols();
- for(std::vector<Options::OrderedSymbol>::iterator it = orderedSymbols.begin(); it != orderedSymbols.end(); ++it) {
- ObjectFile::Atom* atom = this->findAtom(*it);
- if ( atom != NULL ) {
- std::map<const ObjectFile::Atom*, const ObjectFile::Atom*>::iterator start = followOnStarts.find(atom);
- if ( start != followOnStarts.end() ) {
- // this symbol for the order file corresponds to an atom that is in a cluster that must lay out together
- for(const ObjectFile::Atom* nextAtom = start->second; nextAtom != NULL; nextAtom = followOnNexts[nextAtom]) {
- std::map<const ObjectFile::Atom*, uint32_t>::iterator pos = theOrdinalOverrideMap.find(nextAtom);
- if ( pos == theOrdinalOverrideMap.end() ) {
- theOrdinalOverrideMap[nextAtom] = index++;
- if (log ) fprintf(stderr, "override ordinal %u assigned to %s in cluster from %s\n", index, nextAtom->getDisplayName(), nextAtom->getFile()->getPath());
- }
- else {
- if (log ) fprintf(stderr, "could not order %s as %u because it was already laid out earlier by %s as %u\n",
- atom->getDisplayName(), index, followOnStarts[atom]->getDisplayName(), theOrdinalOverrideMap[atom] );
- }
- }
- }
- else {
- theOrdinalOverrideMap[atom] = index;
- if (log ) fprintf(stderr, "override ordinal %u assigned to %s from %s\n", index, atom->getDisplayName(), atom->getFile()->getPath());
- }
- ++matchCount;
- }
- else {
- if ( fOptions.printOrderFileStatistics() ) {
- if ( it->objectFileName == NULL )
- warning("can't find match for order_file entry: %s", it->symbolName);
- else
- warning("can't find match for order_file entry: %s/%s", it->objectFileName, it->symbolName);
- }
- }
- ++index;
- }
- if ( fOptions.printOrderFileStatistics() && (fOptions.orderedSymbols().size() != matchCount) ) {
- warning("only %u out of %lu order_file symbols were applicable", matchCount, fOptions.orderedSymbols().size() );
- }
- }
-
- // sort atoms
- std::sort(fAllAtoms.begin(), fAllAtoms.end(), Linker::AtomSorter(ordinalOverrideMap, fInitializerAtoms, fTerminatorAtoms));
-
- //fprintf(stderr, "Sorted atoms:\n");
- //for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- // fprintf(stderr, "\t%s, %u %s\t%s\n", (*it)->getSectionName(), (*it)->getSection()->getIndex(), (*it)->getDisplayName(), (*it)->getFile()->getPath());
- //}
-}
-
-
-// make sure given addresses are within reach of branches, etc
-void Linker::tweakLayout()
-{
- // > 2GB images need their large zero fill atoms sorted to the end to keep access with +/- 2GB
- if ( fTotalSize > 0x7F000000 ) {
- fBiggerThanTwoGigOutput = true;
-
- if ( (fTotalSize-fTotalZeroFillSize) > 0x7F000000 )
- throwf("total output size exceeds 2GB (%lldMB)", (fTotalSize-fTotalZeroFillSize)/(1024*1024));
-
- // move very large (>1MB) zero fill atoms to a new section at very end of __DATA segment
- Section* hugeZeroFills = Section::find("__huge", "__DATA", true, true);
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- ObjectFile::Atom* atom = *it;
- if ( atom->isZeroFill() && (atom->getSize() > 1024*1024) && (strcmp(atom->getSegment().getName(), "__DATA") == 0) )
- atom->setSection(hugeZeroFills);
- }
- }
-
- // move all initializers to start of __text section
- if ( fOptions.readerOptions().fAutoOrderInitializers ) {
- // move -init function to front of __text
- if ( fOptions.initFunctionName() != NULL ) {
- ObjectFile::Atom* initAtom = fGlobalSymbolTable.find(fOptions.initFunctionName());
- if ( initAtom == NULL )
- throwf("could not find -init function: \"%s\"", fOptions.initFunctionName());
- moveToFrontOfSection(initAtom);
- }
-
- // move all functions pointed to by __mod_init_func section to front of __text
- Section* initSection = Section::find("__mod_init_func", "__DATA", false, true, false);
- if ( initSection != NULL ) {
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); ++it) {
- if ( (*it)->getSection() == initSection ) {
- std::vector<class ObjectFile::Reference*>& references = (*it)->getReferences();
- if ( references.size() == 1 )
- moveToFrontOfSection(&(references[0]->getTarget()));
- }
- }
- }
- }
-
- // move atoms with relocations to start of __DATA,__data section
- // <rdar://problem/6061558> linker should order __DATA segment to reduce dyld dirtied pages
- if ( fOptions.orderData() ) {
- bool slideable = false;
- switch ( fOptions.outputKind() ) {
- case Options::kDynamicExecutable:
- case Options::kStaticExecutable:
- case Options::kDyld:
- case Options::kPreload:
- case Options::kObjectFile:
- case Options::kKextBundle:
- slideable = false;
- break;
- case Options::kDynamicLibrary:
- case Options::kDynamicBundle:
- slideable = true;
- break;
- }
- const bool hasPreferredLoadAddress = (fOptions.baseAddress() != 0);
- Section* dataSection = Section::find("__data", "__DATA", false, true, false);
- if ( dataSection != NULL ) {
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); ++it) {
- ObjectFile::Atom* dataAtom = *it;
- if ( dataAtom->getSection() == dataSection ) {
- std::vector<class ObjectFile::Reference*>& references = dataAtom->getReferences();
- if ( references.size() > 0 ) {
- if ( slideable && !hasPreferredLoadAddress ) {
- // in a slidable image dyld will need to rebase and bind so any references will need runtime fixups
- // if image has preferred base address, assume it will load there and not rebase
- moveToFrontOfSection(dataAtom);
- }
- else {
- // in a non-slideable image, dyld will only do binding, so only references to
- // symbols in another dylib will need runtime fixups
- //fprintf(stderr, "reference from atom %s\n", dataAtom->getDisplayName());
- for (std::vector<ObjectFile::Reference*>::iterator rit=references.begin(); rit != references.end(); rit++) {
- ObjectFile::Reference* reference = *rit;
- //fprintf(stderr, "\t%d %s\n", reference->getTarget().getDefinitionKind(), reference->getTarget().getDisplayName());
- if ( (reference->getTarget().getDefinitionKind() == ObjectFile::Atom::kExternalDefinition)
- || (reference->getTarget().getDefinitionKind() == ObjectFile::Atom::kExternalWeakDefinition) ) {
- moveToFrontOfSection(dataAtom);
- break;
- }
- }
- }
- }
- }
- }
- }
- }
-
-}
-
-
-void Linker::writeDotOutput()
-{
- const char* dotOutFilePath = fOptions.dotOutputFile();
- if ( dotOutFilePath != NULL ) {
- FILE* out = fopen(dotOutFilePath, "w");
- if ( out != NULL ) {
- // print header
- fprintf(out, "digraph dg\n{\n");
- fprintf(out, "\tconcentrate = true;\n");
- fprintf(out, "\trankdir = LR;\n");
-
- // print each atom as a node
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- ObjectFile::Atom* atom = *it;
- if ( atom->getFile() != fOutputFile ) {
- const char* name = atom->getDisplayName();
- if ( (atom->getDefinitionKind() == ObjectFile::Atom::kExternalDefinition)
- || (atom->getDefinitionKind() == ObjectFile::Atom::kExternalWeakDefinition) ) {
- fprintf(out, "\taddr%p [ shape = plaintext, label = \"%s\" ];\n", atom, name);
- }
- else if ( strcmp(atom->getSectionName(), "__cstring") == 0 ) {
- char cstring[atom->getSize()+2];
- atom->copyRawContent((uint8_t*)cstring);
- fprintf(out, "\taddr%p [ label = \"string: '", atom);
- for (const char* s=cstring; *s != '\0'; ++s) {
- if ( *s == '\n' )
- fprintf(out, "\\\\n");
- else
- fputc(*s, out);
- }
- fprintf(out, "'\" ];\n");
- }
- else {
- fprintf(out, "\taddr%p [ label = \"%s\" ];\n", atom, name);
- }
- }
- }
- fprintf(out, "\n");
-
- // print each reference as an edge
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- ObjectFile::Atom* fromAtom = *it;
- if ( fromAtom->getFile() != fOutputFile ) {
- std::vector<ObjectFile::Reference*>& references = fromAtom->getReferences();
- std::set<ObjectFile::Atom*> seenTargets;
- for (std::vector<ObjectFile::Reference*>::iterator rit=references.begin(); rit != references.end(); rit++) {
- ObjectFile::Reference* reference = *rit;
- ObjectFile::Atom* toAtom = &(reference->getTarget());
- if ( seenTargets.count(toAtom) == 0 ) {
- seenTargets.insert(toAtom);
- fprintf(out, "\taddr%p -> addr%p;\n", fromAtom, toAtom);
- }
- }
- }
- }
- fprintf(out, "\n");
-
- // push all imports to bottom of graph
- fprintf(out, "{ rank = same; ");
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- ObjectFile::Atom* atom = *it;
- if ( atom->getFile() != fOutputFile )
- if ( (atom->getDefinitionKind() == ObjectFile::Atom::kExternalDefinition)
- || (atom->getDefinitionKind() == ObjectFile::Atom::kExternalWeakDefinition) ) {
- fprintf(out, "addr%p; ", atom);
- }
- }
- fprintf(out, "};\n ");
-
- // print footer
- fprintf(out, "}\n");
- fclose(out);
- }
- else {
- warning("could not write dot output file: %s", dotOutFilePath);
- }
- }
-}
-
-ObjectFile::Atom* Linker::entryPoint(bool orInit, bool searchArchives)
-{
- // if main executable, find entry point atom
- ObjectFile::Atom* entryPoint = NULL;
- switch ( fOptions.outputKind() ) {
- case Options::kDynamicExecutable:
- case Options::kStaticExecutable:
- case Options::kDyld:
- case Options::kPreload:
- entryPoint = fGlobalSymbolTable.find(fOptions.entryName());
- if ( (entryPoint == NULL) && searchArchives ) {
- // <rdar://problem/7043256> ld64 can not find a -e entry point from an archive
- this->addJustInTimeAtoms(fOptions.entryName(), false, true, false);
- entryPoint = fGlobalSymbolTable.find(fOptions.entryName());
- }
- if ( entryPoint == NULL ) {
- throwf("could not find entry point \"%s\" (perhaps missing crt1.o)", fOptions.entryName());
- }
- break;
- case Options::kDynamicLibrary:
- if ( orInit && (fOptions.initFunctionName() != NULL) ) {
- entryPoint = fGlobalSymbolTable.find(fOptions.initFunctionName());
- if ( entryPoint == NULL ) {
- throwf("could not find -init function: \"%s\"", fOptions.initFunctionName());
- }
- }
- break;
- case Options::kObjectFile:
- case Options::kDynamicBundle:
- case Options::kKextBundle:
- entryPoint = NULL;
- break;
- }
- return entryPoint;
-}
-
-ObjectFile::Atom* Linker::dyldClassicHelper()
-{
- if ( fOptions.makeClassicDyldInfo() )
- return fGlobalSymbolTable.find("dyld_stub_binding_helper");
- else
- return NULL;
-}
-
-ObjectFile::Atom* Linker::dyldCompressedHelper()
-{
- if ( fOptions.makeCompressedDyldInfo() ) {
- // dyld_stub_binder is in libSystem.B.dylib
- ObjectFile::Atom* atom = fGlobalSymbolTable.find("dyld_stub_binder");
- if ( atom == NULL ) {
- this->addJustInTimeAtoms("dyld_stub_binder", true, false, true);
- }
- atom = fGlobalSymbolTable.find("dyld_stub_binder");
- return atom;
- }
- else
- return NULL;
-}
-
-ObjectFile::Atom* Linker::dyldLazyLibraryHelper()
-{
- return fGlobalSymbolTable.find("dyld_lazy_dylib_stub_binding_helper");
-}
-
-const char* Linker::assureFullPath(const char* path)
-{
- if ( path[0] == '/' )
- return path;
- char cwdbuff[MAXPATHLEN];
- if ( getcwd(cwdbuff, MAXPATHLEN) != NULL ) {
- char* result;
- asprintf(&result, "%s/%s", cwdbuff, path);
- if ( result != NULL )
- return result;
- }
- return path;
-}
-
-
-//
-// The stab strings are of the form:
-// <name> ':' <type-code> <number-pari>
-// but the <name> contain a colon.
-// For C++ <name> may contain a double colon (e.g. std::string:f(0,1) )
-// For Objective-C name may contain a colon instead square bracket (e.g. [Foo doit:]:f(0,1) )
-//
-const char* Linker::truncateStabString(const char* str)
-{
- enum { start, inObjc } state = start;
- for (const char* s = str; *s != 0; ++s) {
- char c = *s;
- switch (state) {
- case start:
- if ( c == '[' ) {
- state = inObjc;
- }
- else {
- if ( c == ':' ) {
- if ( s[1] == ':' ) {
- ++s;
- }
- else {
- // found colon
- // Duplicate strndup behavior here.
- int trunStrLen = s-str+2;
- char* temp = new char[trunStrLen+1];
- memcpy(temp, str, trunStrLen);
- temp[trunStrLen] = '\0';
- return temp;
- }
- }
- }
- break;
- case inObjc:
- if ( c == ']' ) {
- state = start;
- }
- break;
- }
- }
- // malformed
- return str;
-}
-
-
-bool Linker::minimizeStab(ObjectFile::Reader::Stab& stab)
-{
- switch(stab.type){
- case N_GSYM:
- case N_STSYM:
- case N_LCSYM:
- case N_FUN:
- // these all need truncated strings
- stab.string = truncateStabString(stab.string);
- return true;
- case N_SO:
- case N_OSO:
- case N_OPT:
- case N_SOL:
- // these are included in the minimal stabs, but they keep their full string
- return true;
- default:
- return false;
- }
-}
-
-
-struct HeaderRange {
- std::vector<ObjectFile::Reader::Stab>::iterator begin;
- std::vector<ObjectFile::Reader::Stab>::iterator end;
- int parentRangeIndex;
- uint32_t sum;
- bool sumPrecomputed;
- bool useEXCL;
- bool cannotEXCL; // because of SLINE, etc stabs
-};
-
-
-typedef __gnu_cxx::hash_map<const char*, std::vector<uint32_t>, __gnu_cxx::hash<const char*>, CStringEquals> PathToSums;
-
-// hash table that maps header path to a vector of known checksums for that path
-static PathToSums sKnownBINCLs;
-
-
-void Linker::collectStabs(ObjectFile::Reader* reader, std::map<const class ObjectFile::Atom*, uint32_t>& atomOrdinals)
-{
- const bool log = false;
- bool minimal = ( fOptions.readerOptions().fDebugInfoStripping == ObjectFile::ReaderOptions::kDebugInfoMinimal );
- std::vector<class ObjectFile::Reader::Stab>* readerStabs = reader->getStabs();
- if ( readerStabs == NULL )
- return;
-
- if ( log ) fprintf(stderr, "processesing %lu stabs for %s\n", readerStabs->size(), reader->getPath());
- std::vector<HeaderRange> ranges;
- int curRangeIndex = -1;
- int count = 0;
- ObjectFile::Atom* atomWithLowestOrdinal = NULL;
- ObjectFile::Atom* atomWithHighestOrdinal = NULL;
- uint32_t highestOrdinal = 0;
- uint32_t lowestOrdinal = UINT_MAX;
- std::vector<std::pair<ObjectFile::Atom*,ObjectFile::Atom*> > soRanges;
- // 1) find all (possibly nested) BINCL/EINCL ranges and their checksums
- // 2) find all SO/SO ranges and the first/last atom own by a FUN stab therein
- for(std::vector<class ObjectFile::Reader::Stab>::iterator it=readerStabs->begin(); it != readerStabs->end(); ++it) {
- ++count;
- switch ( it->type ) {
- case N_BINCL:
- {
- HeaderRange range;
- range.begin = it;
- range.end = readerStabs->end();
- range.parentRangeIndex = curRangeIndex;
- range.sum = it->value;
- range.sumPrecomputed = (range.sum != 0);
- range.useEXCL = false;
- range.cannotEXCL = false;
- curRangeIndex = ranges.size();
- if ( log ) fprintf(stderr, "[%d]BINCL %s\n", curRangeIndex, it->string);
- ranges.push_back(range);
- }
- break;
- case N_EINCL:
- if ( curRangeIndex == -1 ) {
- warning("EINCL missing BINCL in %s", reader->getPath());
- }
- else {
- ranges[curRangeIndex].end = it+1;
- if ( log ) fprintf(stderr, "[%d->%d]EINCL %s\n", curRangeIndex, ranges[curRangeIndex].parentRangeIndex, it->string);
- curRangeIndex = ranges[curRangeIndex].parentRangeIndex;
- }
- break;
- case N_FUN:
- {
- std::map<const class ObjectFile::Atom*, uint32_t>::iterator pos = atomOrdinals.find(it->atom);
- if ( pos != atomOrdinals.end() ) {
- uint32_t ordinal = pos->second;
- if ( ordinal > highestOrdinal ) {
- highestOrdinal = ordinal;
- atomWithHighestOrdinal = it->atom;
- }
- if ( ordinal < lowestOrdinal ) {
- lowestOrdinal = ordinal;
- atomWithLowestOrdinal = it->atom;
- }
- }
- }
- // fall through
- case N_BNSYM:
- case N_ENSYM:
- case N_LBRAC:
- case N_RBRAC:
- case N_SLINE:
- case N_STSYM:
- case N_LCSYM:
- if ( curRangeIndex != -1 ) {
- ranges[curRangeIndex].cannotEXCL = true;
- if ( fOptions.warnStabs() )
- warning("cannot do BINCL/EINCL optimzation because of stabs kinds in %s for %s\n", ranges[curRangeIndex].begin->string, reader->getPath());
- }
- break;
- case N_SO:
- if ( (it->string != NULL) && (strlen(it->string) > 0) ) {
- // start SO, reset hi/low FUN tracking
- atomWithLowestOrdinal = NULL;
- atomWithHighestOrdinal = NULL;
- highestOrdinal = 0;
- lowestOrdinal = UINT_MAX;
- }
- else {
- // end SO, record hi/low atoms for this SO range
- soRanges.push_back(std::make_pair<ObjectFile::Atom*,ObjectFile::Atom*>(atomWithLowestOrdinal, atomWithHighestOrdinal));
- }
- // fall through
- default:
- if ( curRangeIndex != -1 ) {
- if ( ! ranges[curRangeIndex].sumPrecomputed ) {
- uint32_t sum = 0;
- const char* s = it->string;
- char c;
- while ( (c = *s++) != 0 ) {
- sum += c;
- // don't checkusm first number (file index) after open paren in string
- if ( c == '(' ) {
- while(isdigit(*s))
- ++s;
- }
- }
- ranges[curRangeIndex].sum += sum;
- }
- }
-
- }
- }
- if ( log ) fprintf(stderr, "processesed %d stabs for %s\n", count, reader->getPath());
- if ( curRangeIndex != -1 )
- warning("BINCL (%s) missing EINCL in %s", ranges[curRangeIndex].begin->string, reader->getPath());
-
- // if no BINCLs
- if ( ranges.size() == 0 ) {
- unsigned int soIndex = 0;
- for(std::vector<ObjectFile::Reader::Stab>::iterator it=readerStabs->begin(); it != readerStabs->end(); ++it) {
- // copy minimal or all stabs
- ObjectFile::Reader::Stab stab = *it;
- if ( !minimal || minimizeStab(stab) ) {
- if ( stab.type == N_SO ) {
- if ( soIndex < soRanges.size() ) {
- if ( (stab.string != NULL) && (strlen(stab.string) > 0) ) {
- // starting SO is associated with first atom
- stab.atom = soRanges[soIndex].first;
- }
- else {
- // ending SO is associated with last atom
- stab.atom = soRanges[soIndex].second;
- ++soIndex;
- }
- }
- }
- fStabs.push_back(stab);
- }
- }
- return;
- }
-
- //fprintf(stderr, "BINCL/EINCL info for %s\n", reader->getPath());
- //for(std::vector<HeaderRange>::iterator it=ranges.begin(); it != ranges.end(); ++it) {
- // fprintf(stderr, "%08X %s\n", it->sum, it->begin->string);
- //}
-
- // see if any of these BINCL/EINCL ranges have already been seen and therefore can be replaced with EXCL
- for(std::vector<HeaderRange>::iterator it=ranges.begin(); it != ranges.end(); ++it) {
- if ( ! it->cannotEXCL ) {
- const char* header = it->begin->string;
- uint32_t sum = it->sum;
- PathToSums::iterator pos = sKnownBINCLs.find(header);
- if ( pos != sKnownBINCLs.end() ) {
- std::vector<uint32_t>& sums = pos->second;
- for(std::vector<uint32_t>::iterator sit=sums.begin(); sit != sums.end(); ++sit) {
- if (*sit == sum) {
- //fprintf(stderr, "use EXCL for %s in %s\n", header, reader->getPath());
- it->useEXCL = true;
- break;
- }
- }
- if ( ! it->useEXCL ) {
- // have seen this path, but not this checksum
- //fprintf(stderr, "registering another checksum %08X for %s\n", sum, header);
- sums.push_back(sum);
- }
- }
- else {
- // have not seen this path, so add to known BINCLs
- std::vector<uint32_t> empty;
- sKnownBINCLs[header] = empty;
- sKnownBINCLs[header].push_back(sum);
- //fprintf(stderr, "registering checksum %08X for %s\n", sum, header);
- }
- }
- }
-
- // add a new set of stabs with BINCL/EINCL runs that have been seen before, replaced with EXCLs
- curRangeIndex = -1;
- const int maxRangeIndex = ranges.size();
- int soIndex = 0;
- for(std::vector<ObjectFile::Reader::Stab>::iterator it=readerStabs->begin(); it != readerStabs->end(); ++it) {
- switch ( it->type ) {
- case N_BINCL:
- for(int i=curRangeIndex+1; i < maxRangeIndex; ++i) {
- if ( ranges[i].begin == it ) {
- curRangeIndex = i;
- HeaderRange& range = ranges[curRangeIndex];
- ObjectFile::Reader::Stab stab = *it;
- stab.value = range.sum; // BINCL and EXCL have n_value set to checksum
- if ( range.useEXCL )
- stab.type = N_EXCL; // transform BINCL into EXCL
- if ( !minimal )
- fStabs.push_back(stab);
- break;
- }
- }
- break;
- case N_EINCL:
- if ( curRangeIndex != -1 ) {
- if ( !ranges[curRangeIndex].useEXCL && !minimal )
- fStabs.push_back(*it);
- curRangeIndex = ranges[curRangeIndex].parentRangeIndex;
- }
- break;
- default:
- if ( (curRangeIndex == -1) || !ranges[curRangeIndex].useEXCL ) {
- ObjectFile::Reader::Stab stab = *it;
- if ( !minimal || minimizeStab(stab) ) {
- if ( stab.type == N_SO ) {
- if ( (stab.string != NULL) && (strlen(stab.string) > 0) ) {
- // starting SO is associated with first atom
- stab.atom = soRanges[soIndex].first;
- }
- else {
- // ending SO is associated with last atom
- stab.atom = soRanges[soIndex].second;
- ++soIndex;
- }
- }
- fStabs.push_back(stab);
- }
- }
- }
- }
-
-}
-
-
-// used to prune out atoms that don't need debug notes generated
-class NoDebugNoteAtom
-{
-public:
- NoDebugNoteAtom(const std::map<class ObjectFile::Reader*, uint32_t>& readersWithDwarfOrdinals)
- : fReadersWithDwarfOrdinals(readersWithDwarfOrdinals) {}
-
- bool operator()(const ObjectFile::Atom* atom) const {
- if ( atom->getSymbolTableInclusion() == ObjectFile::Atom::kSymbolTableNotIn )
- return true;
- if ( atom->getName() == NULL )
- return true;
- if ( fReadersWithDwarfOrdinals.find(atom->getFile()) == fReadersWithDwarfOrdinals.end() )
- return true;
- return false;
- }
-
-private:
- const std::map<class ObjectFile::Reader*, uint32_t>& fReadersWithDwarfOrdinals;
-};
-
-// used to sort atoms with debug notes
-class ReadersWithDwarfSorter
-{
-public:
- ReadersWithDwarfSorter(const std::map<class ObjectFile::Reader*, uint32_t>& readersWithDwarfOrdinals,
- const std::map<const class ObjectFile::Atom*, uint32_t>& atomOrdinals)
- : fReadersWithDwarfOrdinals(readersWithDwarfOrdinals), fAtomOrdinals(atomOrdinals) {}
-
- bool operator()(const ObjectFile::Atom* left, const ObjectFile::Atom* right) const
- {
- // first sort by reader
- unsigned int leftReaderIndex = fReadersWithDwarfOrdinals.find(left->getFile())->second;
- unsigned int rightReaderIndex = fReadersWithDwarfOrdinals.find(right->getFile())->second;
- if ( leftReaderIndex != rightReaderIndex )
- return (leftReaderIndex < rightReaderIndex);
-
- // then sort by atom ordinal
- unsigned int leftAtomIndex = fAtomOrdinals.find(left)->second;
- unsigned int rightAtomIndex = fAtomOrdinals.find(right)->second;
- return leftAtomIndex < rightAtomIndex;
- }
-
-private:
- const std::map<class ObjectFile::Reader*, uint32_t>& fReadersWithDwarfOrdinals;
- const std::map<const class ObjectFile::Atom*, uint32_t>& fAtomOrdinals;
-};
-
-
-
-
-
-void Linker::synthesizeDebugNotes(std::vector<class ObjectFile::Atom*>& allAtomsByReader)
-{
- // synthesize "debug notes" and add them to master stabs vector
- const char* dirPath = NULL;
- const char* filename = NULL;
- bool wroteStartSO = false;
- bool useZeroOSOModTime = (getenv("RC_RELEASE") != NULL);
- __gnu_cxx::hash_set<const char*, __gnu_cxx::hash<const char*>, CStringEquals> seenFiles;
- for (std::vector<ObjectFile::Atom*>::iterator it=allAtomsByReader.begin(); it != allAtomsByReader.end(); it++) {
- ObjectFile::Atom* atom = *it;
- const char* newDirPath;
- const char* newFilename;
- //fprintf(stderr, "debug note for %s\n", atom->getDisplayName());
- if ( atom->getTranslationUnitSource(&newDirPath, &newFilename) ) {
- // need SO's whenever the translation unit source file changes
- if ( newFilename != filename ) {
- // gdb like directory SO's to end in '/', but dwarf DW_AT_comp_dir usually does not have trailing '/'
- if ( (newDirPath != NULL) && (strlen(newDirPath) > 1 ) && (newDirPath[strlen(newDirPath)-1] != '/') )
- asprintf((char**)&newDirPath, "%s/", newDirPath);
- if ( filename != NULL ) {
- // translation unit change, emit ending SO
- ObjectFile::Reader::Stab endFileStab;
- endFileStab.atom = NULL;
- endFileStab.type = N_SO;
- endFileStab.other = 1;
- endFileStab.desc = 0;
- endFileStab.value = 0;
- endFileStab.string = "";
- fStabs.push_back(endFileStab);
- }
- // new translation unit, emit start SO's
- ObjectFile::Reader::Stab dirPathStab;
- dirPathStab.atom = NULL;
- dirPathStab.type = N_SO;
- dirPathStab.other = 0;
- dirPathStab.desc = 0;
- dirPathStab.value = 0;
- dirPathStab.string = newDirPath;
- fStabs.push_back(dirPathStab);
- ObjectFile::Reader::Stab fileStab;
- fileStab.atom = NULL;
- fileStab.type = N_SO;
- fileStab.other = 0;
- fileStab.desc = 0;
- fileStab.value = 0;
- fileStab.string = newFilename;
- fStabs.push_back(fileStab);
- // Synthesize OSO for start of file
- ObjectFile::Reader::Stab objStab;
- objStab.atom = NULL;
- objStab.type = N_OSO;
- // <rdar://problem/6337329> linker should put cpusubtype in n_sect field of nlist entry for N_OSO debug note entries
- objStab.other = atom->getFile()->updateCpuConstraint(0);
- objStab.desc = 1;
- objStab.value = useZeroOSOModTime ? 0 : atom->getFile()->getModificationTime();
- objStab.string = assureFullPath(atom->getFile()->getPath());
- fStabs.push_back(objStab);
- wroteStartSO = true;
- // add the source file path to seenFiles so it does not show up in SOLs
- seenFiles.insert(newFilename);
- }
- filename = newFilename;
- dirPath = newDirPath;
- if ( atom->getSegment().isContentExecutable() && (strncmp(atom->getSectionName(), "__text", 6) == 0) ) {
- // Synthesize BNSYM and start FUN stabs
- ObjectFile::Reader::Stab beginSym;
- beginSym.atom = atom;
- beginSym.type = N_BNSYM;
- beginSym.other = 1;
- beginSym.desc = 0;
- beginSym.value = 0;
- beginSym.string = "";
- fStabs.push_back(beginSym);
- ObjectFile::Reader::Stab startFun;
- startFun.atom = atom;
- startFun.type = N_FUN;
- startFun.other = 1;
- startFun.desc = 0;
- startFun.value = 0;
- startFun.string = atom->getName();
- fStabs.push_back(startFun);
- // Synthesize any SOL stabs needed
- std::vector<ObjectFile::LineInfo>* lineInfo = atom->getLineInfo();
- if ( lineInfo != NULL ) {
- const char* curFile = NULL;
- for (std::vector<ObjectFile::LineInfo>::iterator it = lineInfo->begin(); it != lineInfo->end(); ++it) {
- if ( it->fileName != curFile ) {
- if ( seenFiles.count(it->fileName) == 0 ) {
- seenFiles.insert(it->fileName);
- ObjectFile::Reader::Stab sol;
- sol.atom = 0;
- sol.type = N_SOL;
- sol.other = 0;
- sol.desc = 0;
- sol.value = 0;
- sol.string = it->fileName;
- fStabs.push_back(sol);
- }
- curFile = it->fileName;
- }
- }
- }
- // Synthesize end FUN and ENSYM stabs
- ObjectFile::Reader::Stab endFun;
- endFun.atom = atom;
- endFun.type = N_FUN;
- endFun.other = 0;
- endFun.desc = 0;
- endFun.value = 0;
- endFun.string = "";
- fStabs.push_back(endFun);
- ObjectFile::Reader::Stab endSym;
- endSym.atom = atom;
- endSym.type = N_ENSYM;
- endSym.other = 1;
- endSym.desc = 0;
- endSym.value = 0;
- endSym.string = "";
- fStabs.push_back(endSym);
- }
- else if ( atom->getSymbolTableInclusion() == ObjectFile::Atom::kSymbolTableNotIn ) {
- // no stabs for atoms that would not be in the symbol table
- }
- else if ( atom->getSymbolTableInclusion() == ObjectFile::Atom::kSymbolTableInAsAbsolute ) {
- // no stabs for absolute symbols
- }
- else if ( (strcmp(atom->getSectionName(), "__eh_frame") == 0) ) {
- // no stabs for .eh atoms
- }
- else if ( (strncmp(atom->getName(), "__dtrace_probe$", 15) == 0) ) {
- // no stabs for old style dtrace probes
- }
- else {
- ObjectFile::Reader::Stab globalsStab;
- const char* name = atom->getName();
- if ( atom->getScope() == ObjectFile::Atom::scopeTranslationUnit ) {
- // Synthesize STSYM stab for statics
- globalsStab.atom = atom;
- globalsStab.type = N_STSYM;
- globalsStab.other = 1;
- globalsStab.desc = 0;
- globalsStab.value = 0;
- globalsStab.string = name;
- fStabs.push_back(globalsStab);
- }
- else {
- // Synthesize GSYM stab for other globals
- globalsStab.atom = atom;
- globalsStab.type = N_GSYM;
- globalsStab.other = 1;
- globalsStab.desc = 0;
- globalsStab.value = 0;
- globalsStab.string = name;
- fStabs.push_back(globalsStab);
- }
- }
- }
- }
-
- if ( wroteStartSO ) {
- // emit ending SO
- ObjectFile::Reader::Stab endFileStab;
- endFileStab.atom = NULL;
- endFileStab.type = N_SO;
- endFileStab.other = 1;
- endFileStab.desc = 0;
- endFileStab.value = 0;
- endFileStab.string = "";
- fStabs.push_back(endFileStab);
- }
-}
-
-
-
-
-void Linker::collectDebugInfo()
-{
- std::map<const class ObjectFile::Atom*, uint32_t> atomOrdinals;
- fStartDebugTime = mach_absolute_time();
- if ( fOptions.readerOptions().fDebugInfoStripping != ObjectFile::ReaderOptions::kDebugInfoNone ) {
-
- // determine mixture of stabs and dwarf
- bool someStabs = false;
- bool someDwarf = false;
- for (std::vector<class ObjectFile::Reader*>::iterator it=fReadersThatHaveSuppliedAtoms.begin();
- it != fReadersThatHaveSuppliedAtoms.end();
- it++) {
- ObjectFile::Reader* reader = *it;
- if ( reader != NULL ) {
- switch ( reader->getDebugInfoKind() ) {
- case ObjectFile::Reader::kDebugInfoNone:
- break;
- case ObjectFile::Reader::kDebugInfoStabs:
- someStabs = true;
- break;
- case ObjectFile::Reader::kDebugInfoDwarf:
- someDwarf = true;
- fCreateUUID = true;
- break;
- case ObjectFile::Reader::kDebugInfoStabsUUID:
- someStabs = true;
- fCreateUUID = true;
- break;
- default:
- throw "Unhandled type of debug information";
- }
- }
- }
-
- if ( someDwarf || someStabs ) {
- // try to minimize re-allocations
- fStabs.reserve(1024);
-
- // make mapping from atoms to ordinal
- uint32_t ordinal = 1;
- for (std::vector<ObjectFile::Atom*>::iterator it=fAllAtoms.begin(); it != fAllAtoms.end(); it++) {
- atomOrdinals[*it] = ordinal++;
- }
- }
-
- // process all dwarf .o files as a batch
- if ( someDwarf ) {
- // make mapping from readers with dwarf to ordinal
- std::map<class ObjectFile::Reader*, uint32_t> readersWithDwarfOrdinals;
- uint32_t readerOrdinal = 1;
- for (std::vector<class ObjectFile::Reader*>::iterator it=fReadersThatHaveSuppliedAtoms.begin();
- it != fReadersThatHaveSuppliedAtoms.end();
- it++) {
- ObjectFile::Reader* reader = *it;
- if ( (reader != NULL) && (reader->getDebugInfoKind() == ObjectFile::Reader::kDebugInfoDwarf) ) {
- readersWithDwarfOrdinals[reader] = readerOrdinal++;
- }
- }
-
- // make a vector of atoms
- std::vector<class ObjectFile::Atom*> allAtomsByReader(fAllAtoms.begin(), fAllAtoms.end());
- // remove those not from a reader that has dwarf
- allAtomsByReader.erase(std::remove_if(allAtomsByReader.begin(), allAtomsByReader.end(),
- NoDebugNoteAtom(readersWithDwarfOrdinals)), allAtomsByReader.end());
- // sort by reader then atom ordinal
- std::sort(allAtomsByReader.begin(), allAtomsByReader.end(), ReadersWithDwarfSorter(readersWithDwarfOrdinals, atomOrdinals));
- // add debug notes for each atom
- this->synthesizeDebugNotes(allAtomsByReader);
- }
-
- // process all stabs .o files one by one
- if ( someStabs ) {
- // get stabs from each reader, in command line order
- for (std::vector<class ObjectFile::Reader*>::iterator it=fReadersThatHaveSuppliedAtoms.begin();
- it != fReadersThatHaveSuppliedAtoms.end();
- it++) {
- ObjectFile::Reader* reader = *it;
- if ( reader != NULL ) {
- switch ( reader->getDebugInfoKind() ) {
- case ObjectFile::Reader::kDebugInfoDwarf:
- case ObjectFile::Reader::kDebugInfoNone:
- // do nothing
- break;
- case ObjectFile::Reader::kDebugInfoStabs:
- case ObjectFile::Reader::kDebugInfoStabsUUID:
- collectStabs(reader, atomOrdinals);
- break;
- default:
- throw "Unhandled type of debug information";
- }
- }
- }
- // remove stabs associated with atoms that won't be in output
- std::set<class ObjectFile::Atom*> allAtomsSet;
- allAtomsSet.insert(fAllAtoms.begin(), fAllAtoms.end());
- fStabs.erase(std::remove_if(fStabs.begin(), fStabs.end(), NotInSet(allAtomsSet)), fStabs.end());
- }
- }
-}
-
-void Linker::writeOutput()
-{
- // <rdar://problem/6933931> ld -r of empty .o file should preserve sub-type
- // <rdar://problem/7049478> empty dylib should have subtype from command line
- if ( fOptions.preferSubArchitecture() && (fOptions.architecture() == CPU_TYPE_ARM) ) {
- fCurrentCpuConstraint = (ObjectFile::Reader::CpuConstraint)fOptions.subArchitecture();
- }
-
- if ( fOptions.forceCpuSubtypeAll() )
- fCurrentCpuConstraint = ObjectFile::Reader::kCpuAny;
-
- fStartWriteTime = mach_absolute_time();
- // tell writer about each segment's atoms
- fOutputFileSize = fOutputFile->write(fAllAtoms, fStabs, this->entryPoint(true),
- fCreateUUID, fCanScatter,
- fCurrentCpuConstraint,
- fRegularDefAtomsThatOverrideADylibsWeakDef,
- fGlobalSymbolTable.hasExternalWeakDefinitions());
-}
-
-const char* Linker::fileArch(const void* p)
-{
- const uint8_t* bytes = (uint8_t*)p;
- const char* result;
- result = mach_o::relocatable::Reader<ppc>::fileKind(bytes);
- if ( result != NULL )
- return result;
- result = mach_o::relocatable::Reader<ppc64>::fileKind(bytes);
- if ( result != NULL )
- return result;
- result = mach_o::relocatable::Reader<x86>::fileKind(bytes);
- if ( result != NULL )
- return result;
- result = mach_o::relocatable::Reader<x86_64>::fileKind(bytes);
- if ( result != NULL )
- return result;
- result = mach_o::relocatable::Reader<arm>::fileKind(bytes);
- if ( result != NULL )
- return result;
-
- result = lto::Reader::fileKind(bytes);
- if ( result != NULL )
- return result;
-
- return "unsupported file format";
-}
-
-ObjectFile::Reader* Linker::createReader(const Options::FileInfo& info)
-{
- // map in whole file
- uint64_t len = info.fileLen;
- int fd = ::open(info.path, O_RDONLY, 0);
- if ( fd == -1 )
- throwf("can't open file, errno=%d", errno);
- if ( info.fileLen < 20 )
- throw "file too small";
-
- uint8_t* p = (uint8_t*)::mmap(NULL, info.fileLen, PROT_READ, MAP_FILE | MAP_PRIVATE, fd, 0);
- if ( p == (uint8_t*)(-1) )
- throwf("can't map file, errno=%d", errno);
-
- // if fat file, skip to architecture we want
- // Note: fat header is always big-endian
- bool isFatFile = false;
- const fat_header* fh = (fat_header*)p;
- if ( fh->magic == OSSwapBigToHostInt32(FAT_MAGIC) ) {
- isFatFile = true;
- const struct fat_arch* archs = (struct fat_arch*)(p + sizeof(struct fat_header));
- uint32_t sliceToUse;
- bool sliceFound = false;
- if ( fOptions.preferSubArchitecture() ) {
- // first try to find a slice that match cpu-type and cpu-sub-type
- for (uint32_t i=0; i < OSSwapBigToHostInt32(fh->nfat_arch); ++i) {
- if ( (OSSwapBigToHostInt32(archs[i].cputype) == (uint32_t)fArchitecture)
- && (OSSwapBigToHostInt32(archs[i].cpusubtype) == (uint32_t)fOptions.subArchitecture()) ) {
- sliceToUse = i;
- sliceFound = true;
- break;
- }
- }
- }
- if ( !sliceFound ) {
- // look for any slice that matches just cpu-type
- for (uint32_t i=0; i < OSSwapBigToHostInt32(fh->nfat_arch); ++i) {
- if ( OSSwapBigToHostInt32(archs[i].cputype) == (uint32_t)fArchitecture ) {
- sliceToUse = i;
- sliceFound = true;
- break;
- }
- }
- }
- if ( sliceFound ) {
- uint32_t fileOffset = OSSwapBigToHostInt32(archs[sliceToUse].offset);
- len = OSSwapBigToHostInt32(archs[sliceToUse].size);
- // if requested architecture is page aligned within fat file, then remap just that portion of file
- if ( (fileOffset & 0x00000FFF) == 0 ) {
- // unmap whole file
- munmap((caddr_t)p, info.fileLen);
- // re-map just part we need
- p = (uint8_t*)::mmap(NULL, len, PROT_READ, MAP_FILE | MAP_PRIVATE, fd, fileOffset);
- if ( p == (uint8_t*)(-1) )
- throwf("can't re-map file, errno=%d", errno);
- }
- else {
- p = &p[fileOffset];
- }
- }
- }
- ::close(fd);
-
- bool objSubtypeMustMatch = (fOptions.preferSubArchitecture() && !fOptions.allowSubArchitectureMismatches());
- switch (fArchitecture) {
- case CPU_TYPE_POWERPC:
- if ( mach_o::relocatable::Reader<ppc>::validFile(p) )
- return this->addObject(new mach_o::relocatable::Reader<ppc>::Reader(p, info.path, info.modTime, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- else if ( mach_o::dylib::Reader<ppc>::validFile(p, info.options.fBundleLoader) )
- return this->addDylib(new mach_o::dylib::Reader<ppc>::Reader(p, len, info.path, info.options, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- else if ( archive::Reader<ppc>::validFile(p, len) )
- return this->addArchive(new archive::Reader<ppc>::Reader(p, len, info.path, info.modTime, info.options, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- break;
- case CPU_TYPE_POWERPC64:
- if ( mach_o::relocatable::Reader<ppc64>::validFile(p) )
- return this->addObject(new mach_o::relocatable::Reader<ppc64>::Reader(p, info.path, info.modTime, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- else if ( mach_o::dylib::Reader<ppc64>::validFile(p, info.options.fBundleLoader) )
- return this->addDylib(new mach_o::dylib::Reader<ppc64>::Reader(p, len, info.path, info.options, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- else if ( archive::Reader<ppc64>::validFile(p, len) )
- return this->addArchive(new archive::Reader<ppc64>::Reader(p, len, info.path, info.modTime, info.options, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- break;
- case CPU_TYPE_I386:
- if ( mach_o::relocatable::Reader<x86>::validFile(p) )
- return this->addObject(new mach_o::relocatable::Reader<x86>::Reader(p, info.path, info.modTime, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- else if ( mach_o::dylib::Reader<x86>::validFile(p, info.options.fBundleLoader) )
- return this->addDylib(new mach_o::dylib::Reader<x86>::Reader(p, len, info.path, info.options, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- else if ( archive::Reader<x86>::validFile(p, len) )
- return this->addArchive(new archive::Reader<x86>::Reader(p, len, info.path, info.modTime, info.options, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- break;
- case CPU_TYPE_X86_64:
- if ( mach_o::relocatable::Reader<x86_64>::validFile(p) )
- return this->addObject(new mach_o::relocatable::Reader<x86_64>::Reader(p, info.path, info.modTime, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- else if ( mach_o::dylib::Reader<x86_64>::validFile(p, info.options.fBundleLoader) )
- return this->addDylib(new mach_o::dylib::Reader<x86_64>::Reader(p, len, info.path, info.options, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- else if ( archive::Reader<x86_64>::validFile(p, len) )
- return this->addArchive(new archive::Reader<x86_64>::Reader(p, len, info.path, info.modTime, info.options, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- case CPU_TYPE_ARM:
- if ( mach_o::relocatable::Reader<arm>::validFile(p, objSubtypeMustMatch, fOptions.subArchitecture()) )
- return this->addObject(new mach_o::relocatable::Reader<arm>::Reader(p, info.path, info.modTime, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- else if ( mach_o::dylib::Reader<arm>::validFile(p, info.options.fBundleLoader) )
- return this->addDylib(new mach_o::dylib::Reader<arm>::Reader(p, len, info.path, info.options, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- else if ( archive::Reader<arm>::validFile(p, len) )
- return this->addArchive(new archive::Reader<arm>::Reader(p, len, info.path, info.modTime, info.options, fOptions.readerOptions(), fNextInputOrdinal), info, len);
- break;
- }
-
-#if LTO_SUPPORT
- if ( lto::Reader::validFile(p, len, fArchitecture) ) {
- return this->addObject(new lto::Reader(p, len, info.path, info.modTime, fOptions.readerOptions(), fArchitecture), info, len);
- }
- else if ( lto::Reader::fileKind((uint8_t*)p) != NULL ) {
- if ( lto::Reader::loaded() ) {
- throwf("file was built for %s which is not the architecture being linked (%s)", fileArch(p), fArchitectureName);
- }
- else {
- const char* libLTO = "libLTO.dylib";
- char ldPath[PATH_MAX];
- char tmpPath[PATH_MAX];
- char libLTOPath[PATH_MAX];
- uint32_t bufSize = PATH_MAX;
- if ( _NSGetExecutablePath(ldPath, &bufSize) != -1 ) {
- if ( realpath(ldPath, tmpPath) != NULL ) {
- char* lastSlash = strrchr(tmpPath, '/');
- if ( lastSlash != NULL )
- strcpy(lastSlash, "/../lib/libLTO.dylib");
- libLTO = tmpPath;
- if ( realpath(tmpPath, libLTOPath) != NULL )
- libLTO = libLTOPath;
- }
- }
- throwf("could not process llvm bitcode object file, because %s could not be loaded", libLTO);
- }
- }
-#endif
- // error handling
- if ( ((fat_header*)p)->magic == OSSwapBigToHostInt32(FAT_MAGIC) ) {
- throwf("missing required architecture %s in file", fArchitectureName);
- }
- else {
- if ( isFatFile )
- throwf("file is universal but does not contain a(n) %s slice", fArchitectureName);
- else
- throwf("file was built for %s which is not the architecture being linked (%s)", fileArch(p), fArchitectureName);
- }
-}
-
-void Linker::logDylib(ObjectFile::Reader* reader, bool indirect)
-{
- if ( fOptions.readerOptions().fTraceDylibs ) {
- const char* fullPath = reader->getPath();
- char realName[MAXPATHLEN];
- if ( realpath(fullPath, realName) != NULL )
- fullPath = realName;
- if ( indirect )
- logTraceInfo("[Logging for XBS] Used indirect dynamic library: %s\n", fullPath);
projects / apple / ld64.git / blobdiff