diff options
| -rw-r--r-- | lld/lib/ReaderWriter/PECOFF/ReaderCOFF.cpp | 225 |
1 files changed, 123 insertions, 102 deletions
diff --git a/lld/lib/ReaderWriter/PECOFF/ReaderCOFF.cpp b/lld/lib/ReaderWriter/PECOFF/ReaderCOFF.cpp index 1e23731dd14..2a5d542f3af 100644 --- a/lld/lib/ReaderWriter/PECOFF/ReaderCOFF.cpp +++ b/lld/lib/ReaderWriter/PECOFF/ReaderCOFF.cpp @@ -213,6 +213,12 @@ private: }; class FileCOFF : public File { +private: + typedef std::vector<const llvm::object::coff_symbol*> SymbolVector; + typedef std::map<const llvm::object::coff_section*, + std::vector<const llvm::object::coff_symbol*>> + SectionToSymbolVectorMap; + public: FileCOFF(const TargetInfo &ti, std::unique_ptr<llvm::MemoryBuffer> MB, llvm::error_code &EC) @@ -229,139 +235,154 @@ public: } Bin.take(); - const llvm::object::coff_file_header *Header = nullptr; - if ((EC = Obj->getHeader(Header))) - return; - // Assign each symbol to the section it's in. If it does not belong to a // section, create an atom for it now. - std::map< const llvm::object::coff_section* - , std::vector<const llvm::object::coff_symbol*>> SectionSymbols; + SectionToSymbolVectorMap definedSymbols; + if ((EC = readSymbolTable(definedSymbols))) + return; + + // Atomize defined symbols. This is a separate pass from readSymbolTable() + // because in order to create an atom for a symbol we need to the adjacent + // symbols. + for (auto &i : definedSymbols) { + const llvm::object::coff_section *section = i.first; + std::vector<const llvm::object::coff_symbol*> &symbols = i.second; + if ((EC = AtomizeDefinedSymbols(section, symbols))) + return; + } + } + + virtual const atom_collection<DefinedAtom> &defined() const { + return DefinedAtoms; + } + + virtual const atom_collection<UndefinedAtom> &undefined() const { + return UndefinedAtoms; + } + + virtual const atom_collection<SharedLibraryAtom> &sharedLibrary() const { + return SharedLibraryAtoms; + } + + virtual const atom_collection<AbsoluteAtom> &absolute() const { + return AbsoluteAtoms; + } + + virtual const TargetInfo &getTargetInfo() const { return _targetInfo; } + +private: + /// Iterate over symbol table to process all symbols. Absolute or undefined + /// symbols are atomized in this method. Defined symbols are not atomized + /// but added to DefinedSymbols for further processing. + error_code readSymbolTable(SectionToSymbolVectorMap &definedSymbols) { + const llvm::object::coff_file_header *Header = nullptr; + if (error_code ec = Obj->getHeader(Header)) + return ec; for (uint32_t i = 0, e = Header->NumberOfSymbols; i != e; ++i) { const llvm::object::coff_symbol *Symb; - if ((EC = Obj->getSymbol(i, Symb))) - return; + if (error_code ec = Obj->getSymbol(i, Symb)) + return ec; llvm::StringRef Name; - if ((EC = Obj->getSymbolName(Symb, Name))) - return; + if (error_code ec = Obj->getSymbolName(Symb, Name)) + return ec; int16_t SectionIndex = Symb->SectionNumber; assert(SectionIndex != llvm::COFF::IMAGE_SYM_DEBUG && - "Cannot atomize IMAGE_SYM_DEBUG!"); + "Cannot atomize IMAGE_SYM_DEBUG!"); + // Skip aux symbols. + i += Symb->NumberOfAuxSymbols; if (SectionIndex == llvm::COFF::IMAGE_SYM_ABSOLUTE) { // Create an absolute atom. AbsoluteAtoms._atoms.push_back( new (AtomStorage.Allocate<COFFAbsoluteAtom>()) COFFAbsoluteAtom(*this, Name, Symb->Value)); - } else if (SectionIndex == llvm::COFF::IMAGE_SYM_UNDEFINED) { + continue; + } + if (SectionIndex == llvm::COFF::IMAGE_SYM_UNDEFINED) { // Create an undefined atom. UndefinedAtoms._atoms.push_back( new (AtomStorage.Allocate<COFFUndefinedAtom>()) COFFUndefinedAtom(*this, Name)); - } else if ( Symb->StorageClass == llvm::COFF::IMAGE_SYM_CLASS_STATIC - && Symb->Value == 0) { - // A symbol with IMAGE_SYM_CLASS_STATIC and zero value represents a - // section name. This is redundant and we can safely skip this here - // because the same section name is also in the section header. - } else { + continue; + } + // A symbol with IMAGE_SYM_CLASS_STATIC and zero value represents a + // section name. This is redundant and we can safely skip such a symbol + // because the same section name is also in the section header. + if (Symb->StorageClass != llvm::COFF::IMAGE_SYM_CLASS_STATIC + || Symb->Value != 0) { // This is actually a defined symbol. Add it to its section's list of // symbols. uint8_t SC = Symb->StorageClass; - // If Symb->Value actually means section offset. - if ( SC == llvm::COFF::IMAGE_SYM_CLASS_EXTERNAL - || SC == llvm::COFF::IMAGE_SYM_CLASS_STATIC - || SC == llvm::COFF::IMAGE_SYM_CLASS_FUNCTION) { - const llvm::object::coff_section *Sec; - if ((EC = Obj->getSection(SectionIndex, Sec))) - return; - assert(Sec && "SectionIndex > 0, Sec must be non-null!"); - SectionSymbols[Sec].push_back(Symb); - } else { + if (SC != llvm::COFF::IMAGE_SYM_CLASS_EXTERNAL + && SC != llvm::COFF::IMAGE_SYM_CLASS_STATIC + && SC != llvm::COFF::IMAGE_SYM_CLASS_FUNCTION) { llvm::errs() << "Unable to create atom for: " << Name << "\n"; - EC = llvm::object::object_error::parse_failed; - return; + return llvm::object::object_error::parse_failed; } - } - // Skip aux symbols. - i += Symb->NumberOfAuxSymbols; - } - - // For each section, sort its symbols by address, then create a defined atom - // for each range. - for (auto &i : SectionSymbols) { - auto &Symbs = i.second; - // Sort symbols by position. - std::stable_sort(Symbs.begin(), Symbs.end(), - // For some reason MSVC fails to allow the lambda in this context with a - // "illegal use of local type in type instantiation". MSVC is clearly - // wrong here. Force a conversion to function pointer to work around. - static_cast<bool(*)(const coff_symbol*, const coff_symbol*)>( - [](const coff_symbol *A, const coff_symbol *B) -> bool { - return A->Value < B->Value; - })); - - if (Symbs.empty()) { - // Create an atom for the entire section. - llvm::ArrayRef<uint8_t> Data; - DefinedAtoms._atoms.push_back( - new (AtomStorage.Allocate<COFFDefinedAtom>()) - COFFDefinedAtom(*this, "", nullptr, i.first, Data)); - continue; - } - - llvm::ArrayRef<uint8_t> SecData; - if ((EC = Obj->getSectionContents(i.first, SecData))) - return; - - // Create an unnamed atom if the first atom isn't at the start of the - // section. - if (Symbs[0]->Value != 0) { - uint64_t Size = Symbs[0]->Value; - llvm::ArrayRef<uint8_t> Data(SecData.data(), Size); - DefinedAtoms._atoms.push_back( - new (AtomStorage.Allocate<COFFDefinedAtom>()) - COFFDefinedAtom(*this, "", nullptr, i.first, Data)); - } - - for (auto si = Symbs.begin(), se = Symbs.end(); si != se; ++si) { - // if this is the last symbol, take up the remaining data. - llvm::ArrayRef<uint8_t> Data; - if (si + 1 == se) { - Data = llvm::ArrayRef<uint8_t>( SecData.data() + (*si)->Value - , SecData.end()); - } else { - Data = llvm::ArrayRef<uint8_t>( SecData.data() + (*si)->Value - , (*(si + 1))->Value - (*si)->Value); - } - llvm::StringRef Name; - if ((EC = Obj->getSymbolName(*si, Name))) - return; - DefinedAtoms._atoms.push_back( - new (AtomStorage.Allocate<COFFDefinedAtom>()) - COFFDefinedAtom(*this, Name, *si, i.first, Data)); + const llvm::object::coff_section *Sec; + if (error_code ec = Obj->getSection(SectionIndex, Sec)) + return ec; + assert(Sec && "SectionIndex > 0, Sec must be non-null!"); + definedSymbols[Sec].push_back(Symb); } } + return error_code::success(); } - virtual const atom_collection<DefinedAtom> &defined() const { - return DefinedAtoms; - } + /// Atomize defined symbols. + error_code AtomizeDefinedSymbols( + const llvm::object::coff_section *section, + std::vector<const llvm::object::coff_symbol*> &symbols) { + // Sort symbols by position. + std::stable_sort(symbols.begin(), symbols.end(), + // For some reason MSVC fails to allow the lambda in this context with a + // "illegal use of local type in type instantiation". MSVC is clearly + // wrong here. Force a conversion to function pointer to work around. + static_cast<bool(*)(const coff_symbol*, const coff_symbol*)>( + [](const coff_symbol *A, const coff_symbol *B) -> bool { + return A->Value < B->Value; + })); + + if (symbols.empty()) { + // Create an atom for the entire section. + llvm::ArrayRef<uint8_t> Data; + DefinedAtoms._atoms.push_back( + new (AtomStorage.Allocate<COFFDefinedAtom>()) + COFFDefinedAtom(*this, "", nullptr, section, Data)); + return error_code::success(); + } - virtual const atom_collection<UndefinedAtom> &undefined() const { - return UndefinedAtoms; - } + llvm::ArrayRef<uint8_t> SecData; + if (error_code ec = Obj->getSectionContents(section, SecData)) + return ec; - virtual const atom_collection<SharedLibraryAtom> &sharedLibrary() const { - return SharedLibraryAtoms; - } + // Create an unnamed atom if the first atom isn't at the start of the + // section. + if (symbols[0]->Value != 0) { + uint64_t Size = symbols[0]->Value; + llvm::ArrayRef<uint8_t> Data(SecData.data(), Size); + DefinedAtoms._atoms.push_back( + new (AtomStorage.Allocate<COFFDefinedAtom>()) + COFFDefinedAtom(*this, "", nullptr, section, Data)); + } - virtual const atom_collection<AbsoluteAtom> &absolute() const { - return AbsoluteAtoms; + for (auto si = symbols.begin(), se = symbols.end(); si != se; ++si) { + const uint8_t *start = SecData.data() + (*si)->Value; + // if this is the last symbol, take up the remaining data. + const uint8_t *end = (si + 1 == se) + ? start + SecData.size() + : SecData.data() + (*(si + 1))->Value; + llvm::ArrayRef<uint8_t> Data(start, end); + llvm::StringRef Name; + if (error_code ec = Obj->getSymbolName(*si, Name)) + return ec; + DefinedAtoms._atoms.push_back( + new (AtomStorage.Allocate<COFFDefinedAtom>()) + COFFDefinedAtom(*this, Name, *si, section, Data)); + } + return error_code::success(); } - virtual const TargetInfo &getTargetInfo() const { return _targetInfo; } - -private: std::unique_ptr<const llvm::object::COFFObjectFile> Obj; atom_collection_vector<DefinedAtom> DefinedAtoms; atom_collection_vector<UndefinedAtom> UndefinedAtoms; |
