//===- llvm-cxxdump.cpp - Dump C++ data in an Object File -------*- C++ -*-===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // Dumps C++ data resident in object files and archives. // //===----------------------------------------------------------------------===// #include "llvm-cxxdump.h" #include "Error.h" #include "llvm/ADT/ArrayRef.h" #include "llvm/Object/Archive.h" #include "llvm/Object/ObjectFile.h" #include "llvm/Object/SymbolSize.h" #include "llvm/Support/Debug.h" #include "llvm/Support/Endian.h" #include "llvm/Support/FileSystem.h" #include "llvm/Support/ManagedStatic.h" #include "llvm/Support/PrettyStackTrace.h" #include "llvm/Support/Signals.h" #include "llvm/Support/TargetRegistry.h" #include "llvm/Support/TargetSelect.h" #include "llvm/Support/raw_ostream.h" #include <map> #include <string> #include <system_error> using namespace llvm; using namespace llvm::object; using namespace llvm::support; namespace opts { cl::list<std::string> InputFilenames(cl::Positional, cl::desc("<input object files>"), cl::ZeroOrMore); } // namespace opts namespace llvm { static void error(std::error_code EC) { if (!EC) return; outs() << "\nError reading file: " << EC.message() << ".\n"; outs().flush(); exit(1); } static void error(Error Err) { if (Err) { logAllUnhandledErrors(std::move(Err), outs(), "Error reading file: "); outs().flush(); exit(1); } } } // namespace llvm static void reportError(StringRef Input, StringRef Message) { if (Input == "-") Input = "<stdin>"; errs() << Input << ": " << Message << "\n"; errs().flush(); exit(1); } static void reportError(StringRef Input, std::error_code EC) { reportError(Input, EC.message()); } static std::map<SectionRef, SmallVector<SectionRef, 1>> SectionRelocMap; static void collectRelocatedSymbols(const ObjectFile *Obj, const SectionRef &Sec, uint64_t SecAddress, uint64_t SymAddress, uint64_t SymSize, StringRef *I, StringRef *E) { uint64_t SymOffset = SymAddress - SecAddress; uint64_t SymEnd = SymOffset + SymSize; for (const SectionRef &SR : SectionRelocMap[Sec]) { for (const object::RelocationRef &Reloc : SR.relocations()) { if (I == E) break; const object::symbol_iterator RelocSymI = Reloc.getSymbol(); if (RelocSymI == Obj->symbol_end()) continue; Expected<StringRef> RelocSymName = RelocSymI->getName(); error(errorToErrorCode(RelocSymName.takeError())); uint64_t Offset = Reloc.getOffset(); if (Offset >= SymOffset && Offset < SymEnd) { *I = *RelocSymName; ++I; } } } } static void collectRelocationOffsets( const ObjectFile *Obj, const SectionRef &Sec, uint64_t SecAddress, uint64_t SymAddress, uint64_t SymSize, StringRef SymName, std::map<std::pair<StringRef, uint64_t>, StringRef> &Collection) { uint64_t SymOffset = SymAddress - SecAddress; uint64_t SymEnd = SymOffset + SymSize; for (const SectionRef &SR : SectionRelocMap[Sec]) { for (const object::RelocationRef &Reloc : SR.relocations()) { const object::symbol_iterator RelocSymI = Reloc.getSymbol(); if (RelocSymI == Obj->symbol_end()) continue; Expected<StringRef> RelocSymName = RelocSymI->getName(); error(errorToErrorCode(RelocSymName.takeError())); uint64_t Offset = Reloc.getOffset(); if (Offset >= SymOffset && Offset < SymEnd) Collection[std::make_pair(SymName, Offset - SymOffset)] = *RelocSymName; } } } static void dumpCXXData(const ObjectFile *Obj) { struct CompleteObjectLocator { StringRef Symbols[2]; ArrayRef<little32_t> Data; }; struct ClassHierarchyDescriptor { StringRef Symbols[1]; ArrayRef<little32_t> Data; }; struct BaseClassDescriptor { StringRef Symbols[2]; ArrayRef<little32_t> Data; }; struct TypeDescriptor { StringRef Symbols[1]; uint64_t AlwaysZero; StringRef MangledName; }; struct ThrowInfo { uint32_t Flags; }; struct CatchableTypeArray { uint32_t NumEntries; }; struct CatchableType { uint32_t Flags; uint32_t NonVirtualBaseAdjustmentOffset; int32_t VirtualBasePointerOffset; uint32_t VirtualBaseAdjustmentOffset; uint32_t Size; StringRef Symbols[2]; }; std::map<std::pair<StringRef, uint64_t>, StringRef> VFTableEntries; std::map<std::pair<StringRef, uint64_t>, StringRef> TIEntries; std::map<std::pair<StringRef, uint64_t>, StringRef> CTAEntries; std::map<StringRef, ArrayRef<little32_t>> VBTables; std::map<StringRef, CompleteObjectLocator> COLs; std::map<StringRef, ClassHierarchyDescriptor> CHDs; std::map<std::pair<StringRef, uint64_t>, StringRef> BCAEntries; std::map<StringRef, BaseClassDescriptor> BCDs; std::map<StringRef, TypeDescriptor> TDs; std::map<StringRef, ThrowInfo> TIs; std::map<StringRef, CatchableTypeArray> CTAs; std::map<StringRef, CatchableType> CTs; std::map<std::pair<StringRef, uint64_t>, StringRef> VTableSymEntries; std::map<std::pair<StringRef, uint64_t>, int64_t> VTableDataEntries; std::map<std::pair<StringRef, uint64_t>, StringRef> VTTEntries; std::map<StringRef, StringRef> TINames; SectionRelocMap.clear(); for (const SectionRef &Section : Obj->sections()) { section_iterator Sec2 = Section.getRelocatedSection(); if (Sec2 != Obj->section_end()) SectionRelocMap[*Sec2].push_back(Section); } uint8_t BytesInAddress = Obj->getBytesInAddress(); std::vector<std::pair<SymbolRef, uint64_t>> SymAddr = object::computeSymbolSizes(*Obj); for (auto &P : SymAddr) { object::SymbolRef Sym = P.first; uint64_t SymSize = P.second; Expected<StringRef> SymNameOrErr = Sym.getName(); error(errorToErrorCode(SymNameOrErr.takeError())); StringRef SymName = *SymNameOrErr; Expected<object::section_iterator> SecIOrErr = Sym.getSection(); error(errorToErrorCode(SecIOrErr.takeError())); object::section_iterator SecI = *SecIOrErr; // Skip external symbols. if (SecI == Obj->section_end()) continue; const SectionRef &Sec = *SecI; // Skip virtual or BSS sections. if (Sec.isBSS() || Sec.isVirtual()) continue; StringRef SecContents; error(Sec.getContents(SecContents)); Expected<uint64_t> SymAddressOrErr = Sym.getAddress(); error(errorToErrorCode(SymAddressOrErr.takeError())); uint64_t SymAddress = *SymAddressOrErr; uint64_t SecAddress = Sec.getAddress(); uint64_t SecSize = Sec.getSize(); uint64_t SymOffset = SymAddress - SecAddress; StringRef SymContents = SecContents.substr(SymOffset, SymSize); // VFTables in the MS-ABI start with '??_7' and are contained within their // own COMDAT section. We then determine the contents of the VFTable by // looking at each relocation in the section. if (SymName.startswith("??_7")) { // Each relocation either names a virtual method or a thunk. We note the // offset into the section and the symbol used for the relocation. collectRelocationOffsets(Obj, Sec, SecAddress, SecAddress, SecSize, SymName, VFTableEntries); } // VBTables in the MS-ABI start with '??_8' and are filled with 32-bit // offsets of virtual bases. else if (SymName.startswith("??_8")) { ArrayRef<little32_t> VBTableData( reinterpret_cast<const little32_t *>(SymContents.data()), SymContents.size() / sizeof(little32_t)); VBTables[SymName] = VBTableData; } // Complete object locators in the MS-ABI start with '??_R4' else if (SymName.startswith("??_R4")) { CompleteObjectLocator COL; COL.Data = makeArrayRef( reinterpret_cast<const little32_t *>(SymContents.data()), 3); StringRef *I = std::begin(COL.Symbols), *E = std::end(COL.Symbols); collectRelocatedSymbols(Obj, Sec, SecAddress, SymAddress, SymSize, I, E); COLs[SymName] = COL; } // Class hierarchy descriptors in the MS-ABI start with '??_R3' else if (SymName.startswith("??_R3")) { ClassHierarchyDescriptor CHD; CHD.Data = makeArrayRef( reinterpret_cast<const little32_t *>(SymContents.data()), 3); StringRef *I = std::begin(CHD.Symbols), *E = std::end(CHD.Symbols); collectRelocatedSymbols(Obj, Sec, SecAddress, SymAddress, SymSize, I, E); CHDs[SymName] = CHD; } // Class hierarchy descriptors in the MS-ABI start with '??_R2' else if (SymName.startswith("??_R2")) { // Each relocation names a base class descriptor. We note the offset into // the section and the symbol used for the relocation. collectRelocationOffsets(Obj, Sec, SecAddress, SymAddress, SymSize, SymName, BCAEntries); } // Base class descriptors in the MS-ABI start with '??_R1' else if (SymName.startswith("??_R1")) { BaseClassDescriptor BCD; BCD.Data = makeArrayRef( reinterpret_cast<const little32_t *>(SymContents.data()) + 1, 5); StringRef *I = std::begin(BCD.Symbols), *E = std::end(BCD.Symbols); collectRelocatedSymbols(Obj, Sec, SecAddress, SymAddress, SymSize, I, E); BCDs[SymName] = BCD; } // Type descriptors in the MS-ABI start with '??_R0' else if (SymName.startswith("??_R0")) { const char *DataPtr = SymContents.drop_front(BytesInAddress).data(); TypeDescriptor TD; if (BytesInAddress == 8) TD.AlwaysZero = *reinterpret_cast<const little64_t *>(DataPtr); else TD.AlwaysZero = *reinterpret_cast<const little32_t *>(DataPtr); TD.MangledName = SymContents.drop_front(BytesInAddress * 2); StringRef *I = std::begin(TD.Symbols), *E = std::end(TD.Symbols); collectRelocatedSymbols(Obj, Sec, SecAddress, SymAddress, SymSize, I, E); TDs[SymName] = TD; } // Throw descriptors in the MS-ABI start with '_TI' else if (SymName.startswith("_TI") || SymName.startswith("__TI")) { ThrowInfo TI; TI.Flags = *reinterpret_cast<const little32_t *>(SymContents.data()); collectRelocationOffsets(Obj, Sec, SecAddress, SymAddress, SymSize, SymName, TIEntries); TIs[SymName] = TI; } // Catchable type arrays in the MS-ABI start with _CTA or __CTA. else if (SymName.startswith("_CTA") || SymName.startswith("__CTA")) { CatchableTypeArray CTA; CTA.NumEntries = *reinterpret_cast<const little32_t *>(SymContents.data()); collectRelocationOffsets(Obj, Sec, SecAddress, SymAddress, SymSize, SymName, CTAEntries); CTAs[SymName] = CTA; } // Catchable types in the MS-ABI start with _CT or __CT. else if (SymName.startswith("_CT") || SymName.startswith("__CT")) { const little32_t *DataPtr = reinterpret_cast<const little32_t *>(SymContents.data()); CatchableType CT; CT.Flags = DataPtr[0]; CT.NonVirtualBaseAdjustmentOffset = DataPtr[2]; CT.VirtualBasePointerOffset = DataPtr[3]; CT.VirtualBaseAdjustmentOffset = DataPtr[4]; CT.Size = DataPtr[5]; StringRef *I = std::begin(CT.Symbols), *E = std::end(CT.Symbols); collectRelocatedSymbols(Obj, Sec, SecAddress, SymAddress, SymSize, I, E); CTs[SymName] = CT; } // Construction vtables in the Itanium ABI start with '_ZTT' or '__ZTT'. else if (SymName.startswith("_ZTT") || SymName.startswith("__ZTT")) { collectRelocationOffsets(Obj, Sec, SecAddress, SymAddress, SymSize, SymName, VTTEntries); } // Typeinfo names in the Itanium ABI start with '_ZTS' or '__ZTS'. else if (SymName.startswith("_ZTS") || SymName.startswith("__ZTS")) { TINames[SymName] = SymContents.slice(0, SymContents.find('\0')); } // Vtables in the Itanium ABI start with '_ZTV' or '__ZTV'. else if (SymName.startswith("_ZTV") || SymName.startswith("__ZTV")) { collectRelocationOffsets(Obj, Sec, SecAddress, SymAddress, SymSize, SymName, VTableSymEntries); for (uint64_t SymOffI = 0; SymOffI < SymSize; SymOffI += BytesInAddress) { auto Key = std::make_pair(SymName, SymOffI); if (VTableSymEntries.count(Key)) continue; const char *DataPtr = SymContents.substr(SymOffI, BytesInAddress).data(); int64_t VData; if (BytesInAddress == 8) VData = *reinterpret_cast<const little64_t *>(DataPtr); else VData = *reinterpret_cast<const little32_t *>(DataPtr); VTableDataEntries[Key] = VData; } } // Typeinfo structures in the Itanium ABI start with '_ZTI' or '__ZTI'. else if (SymName.startswith("_ZTI") || SymName.startswith("__ZTI")) { // FIXME: Do something with these! } } for (const auto &VFTableEntry : VFTableEntries) { StringRef VFTableName = VFTableEntry.first.first; uint64_t Offset = VFTableEntry.first.second; StringRef SymName = VFTableEntry.second; outs() << VFTableName << '[' << Offset << "]: " << SymName << '\n'; } for (const auto &VBTable : VBTables) { StringRef VBTableName = VBTable.first; uint32_t Idx = 0; for (little32_t Offset : VBTable.second) { outs() << VBTableName << '[' << Idx << "]: " << Offset << '\n'; Idx += sizeof(Offset); } } for (const auto &COLPair : COLs) { StringRef COLName = COLPair.first; const CompleteObjectLocator &COL = COLPair.second; outs() << COLName << "[IsImageRelative]: " << COL.Data[0] << '\n'; outs() << COLName << "[OffsetToTop]: " << COL.Data[1] << '\n'; outs() << COLName << "[VFPtrOffset]: " << COL.Data[2] << '\n'; outs() << COLName << "[TypeDescriptor]: " << COL.Symbols[0] << '\n'; outs() << COLName << "[ClassHierarchyDescriptor]: " << COL.Symbols[1] << '\n'; } for (const auto &CHDPair : CHDs) { StringRef CHDName = CHDPair.first; const ClassHierarchyDescriptor &CHD = CHDPair.second; outs() << CHDName << "[AlwaysZero]: " << CHD.Data[0] << '\n'; outs() << CHDName << "[Flags]: " << CHD.Data[1] << '\n'; outs() << CHDName << "[NumClasses]: " << CHD.Data[2] << '\n'; outs() << CHDName << "[BaseClassArray]: " << CHD.Symbols[0] << '\n'; } for (const auto &BCAEntry : BCAEntries) { StringRef BCAName = BCAEntry.first.first; uint64_t Offset = BCAEntry.first.second; StringRef SymName = BCAEntry.second; outs() << BCAName << '[' << Offset << "]: " << SymName << '\n'; } for (const auto &BCDPair : BCDs) { StringRef BCDName = BCDPair.first; const BaseClassDescriptor &BCD = BCDPair.second; outs() << BCDName << "[TypeDescriptor]: " << BCD.Symbols[0] << '\n'; outs() << BCDName << "[NumBases]: " << BCD.Data[0] << '\n'; outs() << BCDName << "[OffsetInVBase]: " << BCD.Data[1] << '\n'; outs() << BCDName << "[VBPtrOffset]: " << BCD.Data[2] << '\n'; outs() << BCDName << "[OffsetInVBTable]: " << BCD.Data[3] << '\n'; outs() << BCDName << "[Flags]: " << BCD.Data[4] << '\n'; outs() << BCDName << "[ClassHierarchyDescriptor]: " << BCD.Symbols[1] << '\n'; } for (const auto &TDPair : TDs) { StringRef TDName = TDPair.first; const TypeDescriptor &TD = TDPair.second; outs() << TDName << "[VFPtr]: " << TD.Symbols[0] << '\n'; outs() << TDName << "[AlwaysZero]: " << TD.AlwaysZero << '\n'; outs() << TDName << "[MangledName]: "; outs().write_escaped(TD.MangledName.rtrim(StringRef("\0", 1)), /*UseHexEscapes=*/true) << '\n'; } for (const auto &TIPair : TIs) { StringRef TIName = TIPair.first; const ThrowInfo &TI = TIPair.second; auto dumpThrowInfoFlag = [&](const char *Name, uint32_t Flag) { outs() << TIName << "[Flags." << Name << "]: " << (TI.Flags & Flag ? "true" : "false") << '\n'; }; auto dumpThrowInfoSymbol = [&](const char *Name, int Offset) { outs() << TIName << '[' << Name << "]: "; auto Entry = TIEntries.find(std::make_pair(TIName, Offset)); outs() << (Entry == TIEntries.end() ? "null" : Entry->second) << '\n'; }; outs() << TIName << "[Flags]: " << TI.Flags << '\n'; dumpThrowInfoFlag("Const", 1); dumpThrowInfoFlag("Volatile", 2); dumpThrowInfoSymbol("CleanupFn", 4); dumpThrowInfoSymbol("ForwardCompat", 8); dumpThrowInfoSymbol("CatchableTypeArray", 12); } for (const auto &CTAPair : CTAs) { StringRef CTAName = CTAPair.first; const CatchableTypeArray &CTA = CTAPair.second; outs() << CTAName << "[NumEntries]: " << CTA.NumEntries << '\n'; unsigned Idx = 0; for (auto I = CTAEntries.lower_bound(std::make_pair(CTAName, 0)), E = CTAEntries.upper_bound(std::make_pair(CTAName, UINT64_MAX)); I != E; ++I) outs() << CTAName << '[' << Idx++ << "]: " << I->second << '\n'; } for (const auto &CTPair : CTs) { StringRef CTName = CTPair.first; const CatchableType &CT = CTPair.second; auto dumpCatchableTypeFlag = [&](const char *Name, uint32_t Flag) { outs() << CTName << "[Flags." << Name << "]: " << (CT.Flags & Flag ? "true" : "false") << '\n'; }; outs() << CTName << "[Flags]: " << CT.Flags << '\n'; dumpCatchableTypeFlag("ScalarType", 1); dumpCatchableTypeFlag("VirtualInheritance", 4); outs() << CTName << "[TypeDescriptor]: " << CT.Symbols[0] << '\n'; outs() << CTName << "[NonVirtualBaseAdjustmentOffset]: " << CT.NonVirtualBaseAdjustmentOffset << '\n'; outs() << CTName << "[VirtualBasePointerOffset]: " << CT.VirtualBasePointerOffset << '\n'; outs() << CTName << "[VirtualBaseAdjustmentOffset]: " << CT.VirtualBaseAdjustmentOffset << '\n'; outs() << CTName << "[Size]: " << CT.Size << '\n'; outs() << CTName << "[CopyCtor]: " << (CT.Symbols[1].empty() ? "null" : CT.Symbols[1]) << '\n'; } for (const auto &VTTPair : VTTEntries) { StringRef VTTName = VTTPair.first.first; uint64_t VTTOffset = VTTPair.first.second; StringRef VTTEntry = VTTPair.second; outs() << VTTName << '[' << VTTOffset << "]: " << VTTEntry << '\n'; } for (const auto &TIPair : TINames) { StringRef TIName = TIPair.first; outs() << TIName << ": " << TIPair.second << '\n'; } auto VTableSymI = VTableSymEntries.begin(); auto VTableSymE = VTableSymEntries.end(); auto VTableDataI = VTableDataEntries.begin(); auto VTableDataE = VTableDataEntries.end(); for (;;) { bool SymDone = VTableSymI == VTableSymE; bool DataDone = VTableDataI == VTableDataE; if (SymDone && DataDone) break; if (!SymDone && (DataDone || VTableSymI->first < VTableDataI->first)) { StringRef VTableName = VTableSymI->first.first; uint64_t Offset = VTableSymI->first.second; StringRef VTableEntry = VTableSymI->second; outs() << VTableName << '[' << Offset << "]: "; outs() << VTableEntry; outs() << '\n'; ++VTableSymI; continue; } if (!DataDone && (SymDone || VTableDataI->first < VTableSymI->first)) { StringRef VTableName = VTableDataI->first.first; uint64_t Offset = VTableDataI->first.second; int64_t VTableEntry = VTableDataI->second; outs() << VTableName << '[' << Offset << "]: "; outs() << VTableEntry; outs() << '\n'; ++VTableDataI; continue; } } } static void dumpArchive(const Archive *Arc) { Error Err; for (auto &ArcC : Arc->children(Err)) { Expected<std::unique_ptr<Binary>> ChildOrErr = ArcC.getAsBinary(); if (!ChildOrErr) { // Ignore non-object files. if (auto E = isNotObjectErrorInvalidFileType(ChildOrErr.takeError())) { std::string Buf; raw_string_ostream OS(Buf); logAllUnhandledErrors(std::move(E), OS, ""); OS.flush(); reportError(Arc->getFileName(), Buf); } ChildOrErr.takeError(); continue; } if (ObjectFile *Obj = dyn_cast<ObjectFile>(&*ChildOrErr.get())) dumpCXXData(Obj); else reportError(Arc->getFileName(), cxxdump_error::unrecognized_file_format); } error(std::move(Err)); } static void dumpInput(StringRef File) { // Attempt to open the binary. Expected<OwningBinary<Binary>> BinaryOrErr = createBinary(File); if (!BinaryOrErr) { auto EC = errorToErrorCode(BinaryOrErr.takeError()); reportError(File, EC); return; } Binary &Binary = *BinaryOrErr.get().getBinary(); if (Archive *Arc = dyn_cast<Archive>(&Binary)) dumpArchive(Arc); else if (ObjectFile *Obj = dyn_cast<ObjectFile>(&Binary)) dumpCXXData(Obj); else reportError(File, cxxdump_error::unrecognized_file_format); } int main(int argc, const char *argv[]) { sys::PrintStackTraceOnErrorSignal(argv[0]); PrettyStackTraceProgram X(argc, argv); llvm_shutdown_obj Y; // Initialize targets. llvm::InitializeAllTargetInfos(); // Register the target printer for --version. cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion); cl::ParseCommandLineOptions(argc, argv, "LLVM C++ ABI Data Dumper\n"); // Default to stdin if no filename is specified. if (opts::InputFilenames.size() == 0) opts::InputFilenames.push_back("-"); std::for_each(opts::InputFilenames.begin(), opts::InputFilenames.end(), dumpInput); return EXIT_SUCCESS; }