void IdenticalCodeFolding::findCandidates(FoldingCandidates& pCandidateList) { Module::obj_iterator obj, objEnd = m_Module.obj_end(); for (obj = m_Module.obj_begin(); obj != objEnd; ++obj) { std::set<const LDSection*> funcptr_access_set; typedef std::map<LDSection*, LDSection*> CandidateMap; CandidateMap candidate_map; LDContext::sect_iterator sect, sectEnd = (*obj)->context()->sectEnd(); for (sect = (*obj)->context()->sectBegin(); sect != sectEnd; ++sect) { switch ((*sect)->kind()) { case LDFileFormat::TEXT: { candidate_map.insert( std::make_pair(*sect, reinterpret_cast<LDSection*>(NULL))); break; } case LDFileFormat::Relocation: { LDSection* target = (*sect)->getLink(); if (target->kind() == LDFileFormat::TEXT) { candidate_map[target] = *sect; } // Safe icf if (m_Config.options().getICFMode() == GeneralOptions::ICF::Safe) { RelocData::iterator rel, relEnd = (*sect)->getRelocData()->end(); for (rel = (*sect)->getRelocData()->begin(); rel != relEnd; ++rel) { LDSymbol* sym = rel->symInfo()->outSymbol(); if (sym->hasFragRef() && (sym->type() == ResolveInfo::Function)) { const LDSection* def = &sym->fragRef()->frag()->getParent()->getSection(); if (!isSymCtorOrDtor(*rel->symInfo()) && m_Backend.mayHaveUnsafeFunctionPointerAccess(*target) && m_Backend.getRelocator() ->mayHaveFunctionPointerAccess(*rel)) { funcptr_access_set.insert(def); } } } // for each reloc } break; } default: { // skip break; } } // end of switch } // for each section CandidateMap::iterator candidate, candidateEnd = candidate_map.end(); for (candidate = candidate_map.begin(); candidate != candidateEnd; ++candidate) { if ((m_Config.options().getICFMode() == GeneralOptions::ICF::All) || (funcptr_access_set.count(candidate->first) == 0)) { size_t index = m_KeptSections.size(); m_KeptSections[candidate->first] = ObjectAndId(*obj, index); pCandidateList.push_back( FoldingCandidate(candidate->first, candidate->second, *obj)); } } // for each possible candidate } // for each obj }
void IdenticalCodeFolding::FoldingCandidate::initConstantContent( const TargetLDBackend& pBackend, const IdenticalCodeFolding::KeptSections& pKeptSections) { // Get the static content from text. assert(sect != NULL && sect->hasSectionData()); SectionData::const_iterator frag, fragEnd = sect->getSectionData()->end(); for (frag = sect->getSectionData()->begin(); frag != fragEnd; ++frag) { switch (frag->getKind()) { case Fragment::Region: { const RegionFragment& region = llvm::cast<RegionFragment>(*frag); content.append(region.getRegion().begin(), region.size()); break; } default: { // FIXME: Currently we only take care of RegionFragment. break; } } } // Get the static content from relocs. if (reloc_sect != NULL && reloc_sect->hasRelocData()) { for (Relocation& rel : *reloc_sect->getRelocData()) { llvm::format_object<Relocation::Type, Relocation::Address, Relocation::Address, Relocation::Address> rel_info("%x%llx%llx%llx", rel.type(), rel.symValue(), rel.addend(), rel.place()); char rel_str[48]; rel_info.print(rel_str, sizeof(rel_str)); content.append(rel_str); // Handle the recursive call. LDSymbol* sym = rel.symInfo()->outSymbol(); if ((sym->type() == ResolveInfo::Function) && sym->hasFragRef()) { LDSection* def = &sym->fragRef()->frag()->getParent()->getSection(); if (def == sect) { continue; } } if (!pBackend.isSymbolPreemptible(*rel.symInfo()) && sym->hasFragRef() && (pKeptSections.find( &sym->fragRef()->frag()->getParent()->getSection()) != pKeptSections.end())) { // Mark this reloc as a variable. variable_relocs.push_back(&rel); } else { // TODO: Support inlining merge sections if possible (target-dependent). if ((sym->binding() == ResolveInfo::Local) || (sym->binding() == ResolveInfo::Absolute)) { // ABS or Local symbols. content.append(sym->name()).append(obj->name()).append( obj->path().native()); } else { content.append(sym->name()); } } } } }
bool MipsGNULDBackend::hasEntryInStrTab(const LDSymbol& pSym) const { return ResolveInfo::Section != pSym.type() || m_pGpDispSymbol == &pSym; }