diff options
Diffstat (limited to 'lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp')
| -rw-r--r-- | lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp | 220 |
1 files changed, 197 insertions, 23 deletions
diff --git a/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp b/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp index 4775c75f7211..ddd3259842e2 100644 --- a/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp +++ b/lib/ReaderWriter/MachO/MachONormalizedFileFromAtoms.cpp @@ -22,6 +22,7 @@ #include "MachONormalizedFile.h" #include "ArchHandler.h" +#include "DebugInfo.h" #include "MachONormalizedFileBinaryUtils.h" #include "lld/Core/Error.h" #include "lld/Core/LLVM.h" @@ -34,6 +35,7 @@ #include "llvm/Support/MachO.h" #include <map> #include <system_error> +#include <unordered_set> using llvm::StringRef; using llvm::isa; @@ -120,6 +122,7 @@ public: void copySectionInfo(NormalizedFile &file); void updateSectionInfo(NormalizedFile &file); void buildAtomToAddressMap(); + llvm::Error synthesizeDebugNotes(NormalizedFile &file); llvm::Error addSymbols(const lld::File &atomFile, NormalizedFile &file); void addIndirectSymbols(const lld::File &atomFile, NormalizedFile &file); void addRebaseAndBindingInfo(const lld::File &, NormalizedFile &file); @@ -201,6 +204,7 @@ private: bool _allSourceFilesHaveMinVersions = true; LoadCommandType _minVersionCommandType = (LoadCommandType)0; uint32_t _minVersion = 0; + std::vector<lld::mach_o::Stab> _stabs; }; Util::~Util() { @@ -785,6 +789,158 @@ void Util::buildAtomToAddressMap() { } } +llvm::Error Util::synthesizeDebugNotes(NormalizedFile &file) { + + // Bail out early if we don't need to generate a debug map. + if (_ctx.debugInfoMode() == MachOLinkingContext::DebugInfoMode::noDebugMap) + return llvm::Error::success(); + + std::vector<const DefinedAtom*> atomsNeedingDebugNotes; + std::set<const mach_o::MachOFile*> filesWithStabs; + bool objFileHasDwarf = false; + const File *objFile = nullptr; + + for (SectionInfo *sect : _sectionInfos) { + for (const AtomInfo &info : sect->atomsAndOffsets) { + if (const DefinedAtom *atom = dyn_cast<DefinedAtom>(info.atom)) { + + // FIXME: No stabs/debug-notes for symbols that wouldn't be in the + // symbol table. + // FIXME: No stabs/debug-notes for kernel dtrace probes. + + if (atom->contentType() == DefinedAtom::typeCFI || + atom->contentType() == DefinedAtom::typeCString) + continue; + + // Whenever we encounter a new file, update the 'objfileHasDwarf' flag. + if (&info.atom->file() != objFile) { + objFileHasDwarf = false; + if (const mach_o::MachOFile *atomFile = + dyn_cast<mach_o::MachOFile>(&info.atom->file())) { + if (atomFile->debugInfo()) { + if (isa<mach_o::DwarfDebugInfo>(atomFile->debugInfo())) + objFileHasDwarf = true; + else if (isa<mach_o::StabsDebugInfo>(atomFile->debugInfo())) + filesWithStabs.insert(atomFile); + } + } + } + + // If this atom is from a file that needs dwarf, add it to the list. + if (objFileHasDwarf) + atomsNeedingDebugNotes.push_back(info.atom); + } + } + } + + // Sort atoms needing debug notes by file ordinal, then atom ordinal. + std::sort(atomsNeedingDebugNotes.begin(), atomsNeedingDebugNotes.end(), + [](const DefinedAtom *lhs, const DefinedAtom *rhs) { + if (lhs->file().ordinal() != rhs->file().ordinal()) + return (lhs->file().ordinal() < rhs->file().ordinal()); + return (lhs->ordinal() < rhs->ordinal()); + }); + + // FIXME: Handle <rdar://problem/17689030>: Add -add_ast_path option to \ + // linker which add N_AST stab entry to output + // See OutputFile::synthesizeDebugNotes in ObjectFile.cpp in ld64. + + StringRef oldFileName = ""; + StringRef oldDirPath = ""; + bool wroteStartSO = false; + std::unordered_set<std::string> seenFiles; + for (const DefinedAtom *atom : atomsNeedingDebugNotes) { + const auto &atomFile = cast<mach_o::MachOFile>(atom->file()); + assert(dyn_cast_or_null<lld::mach_o::DwarfDebugInfo>(atomFile.debugInfo()) + && "file for atom needing debug notes does not contain dwarf"); + auto &dwarf = cast<lld::mach_o::DwarfDebugInfo>(*atomFile.debugInfo()); + + auto &tu = dwarf.translationUnitSource(); + StringRef newFileName = tu.name; + StringRef newDirPath = tu.path; + + // Add an SO whenever the TU source file changes. + if (newFileName != oldFileName || newDirPath != oldDirPath) { + // Translation unit change, emit ending SO + if (oldFileName != "") + _stabs.push_back(mach_o::Stab(nullptr, N_SO, 1, 0, 0, "")); + + oldFileName = newFileName; + oldDirPath = newDirPath; + + // If newDirPath doesn't end with a '/' we need to add one: + if (newDirPath.back() != '/') { + char *p = + file.ownedAllocations.Allocate<char>(newDirPath.size() + 2); + memcpy(p, newDirPath.data(), newDirPath.size()); + p[newDirPath.size()] = '/'; + p[newDirPath.size() + 1] = '\0'; + newDirPath = p; + } + + // New translation unit, emit start SOs: + _stabs.push_back(mach_o::Stab(nullptr, N_SO, 0, 0, 0, newDirPath)); + _stabs.push_back(mach_o::Stab(nullptr, N_SO, 0, 0, 0, newFileName)); + + // Synthesize OSO for start of file. + char *fullPath = nullptr; + { + SmallString<1024> pathBuf(atomFile.path()); + if (auto EC = llvm::sys::fs::make_absolute(pathBuf)) + return llvm::errorCodeToError(EC); + fullPath = file.ownedAllocations.Allocate<char>(pathBuf.size() + 1); + memcpy(fullPath, pathBuf.c_str(), pathBuf.size() + 1); + } + + // Get mod time. + uint32_t modTime = 0; + llvm::sys::fs::file_status stat; + if (!llvm::sys::fs::status(fullPath, stat)) + if (llvm::sys::fs::exists(stat)) + modTime = llvm::sys::toTimeT(stat.getLastModificationTime()); + + _stabs.push_back(mach_o::Stab(nullptr, N_OSO, _ctx.getCPUSubType(), 1, + modTime, fullPath)); + // <rdar://problem/6337329> linker should put cpusubtype in n_sect field + // of nlist entry for N_OSO debug note entries. + wroteStartSO = true; + } + + if (atom->contentType() == DefinedAtom::typeCode) { + // Synthesize BNSYM and start FUN stabs. + _stabs.push_back(mach_o::Stab(atom, N_BNSYM, 1, 0, 0, "")); + _stabs.push_back(mach_o::Stab(atom, N_FUN, 1, 0, 0, atom->name())); + // Synthesize any SOL stabs needed + // FIXME: add SOL stabs. + _stabs.push_back(mach_o::Stab(nullptr, N_FUN, 0, 0, + atom->rawContent().size(), "")); + _stabs.push_back(mach_o::Stab(nullptr, N_ENSYM, 1, 0, + atom->rawContent().size(), "")); + } else { + if (atom->scope() == Atom::scopeTranslationUnit) + _stabs.push_back(mach_o::Stab(atom, N_STSYM, 1, 0, 0, atom->name())); + else + _stabs.push_back(mach_o::Stab(nullptr, N_GSYM, 1, 0, 0, atom->name())); + } + } + + // Emit ending SO if necessary. + if (wroteStartSO) + _stabs.push_back(mach_o::Stab(nullptr, N_SO, 1, 0, 0, "")); + + // Copy any stabs from .o file. + for (const auto *objFile : filesWithStabs) { + const auto &stabsList = + cast<mach_o::StabsDebugInfo>(objFile->debugInfo())->stabs(); + for (auto &stab : stabsList) { + // FIXME: Drop stabs whose atoms have been dead-stripped. + _stabs.push_back(stab); + } + } + + return llvm::Error::success(); +} + uint16_t Util::descBits(const DefinedAtom* atom) { uint16_t desc = 0; switch (atom->merge()) { @@ -807,7 +963,8 @@ uint16_t Util::descBits(const DefinedAtom* atom) { desc |= REFERENCED_DYNAMICALLY; if (_archHandler.isThumbFunction(*atom)) desc |= N_ARM_THUMB_DEF; - if (atom->deadStrip() == DefinedAtom::deadStripNever) { + if (atom->deadStrip() == DefinedAtom::deadStripNever && + _ctx.outputMachOType() == llvm::MachO::MH_OBJECT) { if ((atom->contentType() != DefinedAtom::typeInitializerPtr) && (atom->contentType() != DefinedAtom::typeTerminatorPtr)) desc |= N_NO_DEAD_STRIP; @@ -828,7 +985,7 @@ llvm::Error Util::getSymbolTableRegion(const DefinedAtom* atom, case Atom::scopeTranslationUnit: scope = 0; inGlobalsRegion = false; - return llvm::Error(); + return llvm::Error::success(); case Atom::scopeLinkageUnit: if ((_ctx.exportMode() == MachOLinkingContext::ExportMode::whiteList) && _ctx.exportSymbolNamed(atom->name())) { @@ -840,38 +997,55 @@ llvm::Error Util::getSymbolTableRegion(const DefinedAtom* atom, // -keep_private_externs means keep in globals region as N_PEXT. scope = N_PEXT | N_EXT; inGlobalsRegion = true; - return llvm::Error(); + return llvm::Error::success(); } } // scopeLinkageUnit symbols are no longer global once linked. scope = N_PEXT; inGlobalsRegion = false; - return llvm::Error(); + return llvm::Error::success(); case Atom::scopeGlobal: if (_ctx.exportRestrictMode()) { if (_ctx.exportSymbolNamed(atom->name())) { scope = N_EXT; inGlobalsRegion = true; - return llvm::Error(); + return llvm::Error::success(); } else { scope = N_PEXT; inGlobalsRegion = false; - return llvm::Error(); + return llvm::Error::success(); } } else { scope = N_EXT; inGlobalsRegion = true; - return llvm::Error(); + return llvm::Error::success(); } break; } llvm_unreachable("atom->scope() unknown enum value"); } + + llvm::Error Util::addSymbols(const lld::File &atomFile, NormalizedFile &file) { bool rMode = (_ctx.outputMachOType() == llvm::MachO::MH_OBJECT); - // Mach-O symbol table has three regions: locals, globals, undefs. + // Mach-O symbol table has four regions: stabs, locals, globals, undefs. + + // Add all stabs. + for (auto &stab : _stabs) { + Symbol sym; + sym.type = static_cast<NListType>(stab.type); + sym.scope = 0; + sym.sect = stab.other; + sym.desc = stab.desc; + if (stab.atom) + sym.value = _atomToAddress[stab.atom]; + else + sym.value = stab.value; + sym.name = stab.str; + file.stabsSymbols.push_back(sym); + } // Add all local (non-global) symbols in address order std::vector<AtomAndIndex> globals; @@ -965,7 +1139,7 @@ llvm::Error Util::addSymbols(const lld::File &atomFile, file.undefinedSymbols.push_back(sym); } - return llvm::Error(); + return llvm::Error::success(); } const Atom *Util::targetOfLazyPointer(const DefinedAtom *lpAtom) { @@ -1040,15 +1214,15 @@ void Util::addIndirectSymbols(const lld::File &atomFile, NormalizedFile &file) { } } -void Util::addDependentDylibs(const lld::File &atomFile,NormalizedFile &nFile) { +void Util::addDependentDylibs(const lld::File &atomFile, + NormalizedFile &nFile) { // Scan all imported symbols and build up list of dylibs they are from. int ordinal = 1; - for (const SharedLibraryAtom *slAtom : atomFile.sharedLibrary()) { - StringRef loadPath = slAtom->loadName(); - DylibPathToInfo::iterator pos = _dylibInfo.find(loadPath); + for (const auto *dylib : _ctx.allDylibs()) { + DylibPathToInfo::iterator pos = _dylibInfo.find(dylib->installName()); if (pos == _dylibInfo.end()) { DylibInfo info; - bool flatNamespaceAtom = &slAtom->file() == _ctx.flatNamespaceFile(); + bool flatNamespaceAtom = dylib == _ctx.flatNamespaceFile(); // If we're in -flat_namespace mode (or this atom came from the flat // namespace file under -undefined dynamic_lookup) then use the flat @@ -1057,24 +1231,22 @@ void Util::addDependentDylibs(const lld::File &atomFile,NormalizedFile &nFile) { info.ordinal = BIND_SPECIAL_DYLIB_FLAT_LOOKUP; else info.ordinal = ordinal++; - info.hasWeak = slAtom->canBeNullAtRuntime(); + info.hasWeak = false; info.hasNonWeak = !info.hasWeak; - _dylibInfo[loadPath] = info; + _dylibInfo[dylib->installName()] = info; // Unless this was a flat_namespace atom, record the source dylib. if (!flatNamespaceAtom) { DependentDylib depInfo; - depInfo.path = loadPath; + depInfo.path = dylib->installName(); depInfo.kind = llvm::MachO::LC_LOAD_DYLIB; - depInfo.currentVersion = _ctx.dylibCurrentVersion(loadPath); - depInfo.compatVersion = _ctx.dylibCompatVersion(loadPath); + depInfo.currentVersion = _ctx.dylibCurrentVersion(dylib->path()); + depInfo.compatVersion = _ctx.dylibCompatVersion(dylib->path()); nFile.dependentDylibs.push_back(depInfo); } } else { - if ( slAtom->canBeNullAtRuntime() ) - pos->second.hasWeak = true; - else - pos->second.hasNonWeak = true; + pos->second.hasWeak = false; + pos->second.hasNonWeak = !pos->second.hasWeak; } } // Automatically weak link dylib in which all symbols are weak (canBeNull). @@ -1404,6 +1576,8 @@ normalizedFromAtoms(const lld::File &atomFile, util.copySectionInfo(normFile); util.assignAddressesToSections(normFile); util.buildAtomToAddressMap(); + if (auto err = util.synthesizeDebugNotes(normFile)) + return std::move(err); util.updateSectionInfo(normFile); util.copySectionContent(normFile); if (auto ec = util.addSymbols(atomFile, normFile)) { |