+//===-- LLVMSymbolize.cpp -------------------------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Implementation for LLVM symbolization library.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/Symbolize/Symbolize.h"
+
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/Config/config.h"
+#include "llvm/DebugInfo/DWARF/DWARFContext.h"
+#include "llvm/DebugInfo/PDB/PDB.h"
+#include "llvm/DebugInfo/PDB/PDBContext.h"
+#include "llvm/Object/ELFObjectFile.h"
+#include "llvm/Object/MachO.h"
+#include "llvm/Object/SymbolSize.h"
+#include "llvm/Support/COFF.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/Compression.h"
+#include "llvm/Support/DataExtractor.h"
+#include "llvm/Support/Errc.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Path.h"
+#include <sstream>
+#include <stdlib.h>
+
+#if defined(_MSC_VER)
+#include <Windows.h>
+#include <DbgHelp.h>
+#pragma comment(lib, "dbghelp.lib")
+
+// Windows.h conflicts with our COFF header definitions.
+#ifdef IMAGE_FILE_MACHINE_I386
+#undef IMAGE_FILE_MACHINE_I386
+#endif
+#endif
+
+namespace llvm {
+namespace symbolize {
+
+// FIXME: Move this to llvm-symbolizer tool.
+static bool error(std::error_code ec) {
+ if (!ec)
+ return false;
+ errs() << "LLVMSymbolizer: error reading file: " << ec.message() << ".\n";
+ return true;
+}
+
+static DILineInfoSpecifier
+getDILineInfoSpecifier(const LLVMSymbolizer::Options &Opts) {
+ return DILineInfoSpecifier(
+ DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath,
+ Opts.PrintFunctions);
+}
+
+ModuleInfo::ModuleInfo(ObjectFile *Obj, DIContext *DICtx)
+ : Module(Obj), DebugInfoContext(DICtx) {
+ std::unique_ptr<DataExtractor> OpdExtractor;
+ uint64_t OpdAddress = 0;
+ // Find the .opd (function descriptor) section if any, for big-endian
+ // PowerPC64 ELF.
+ if (Module->getArch() == Triple::ppc64) {
+ for (section_iterator Section : Module->sections()) {
+ StringRef Name;
+ if (!error(Section->getName(Name)) && Name == ".opd") {
+ StringRef Data;
+ if (!error(Section->getContents(Data))) {
+ OpdExtractor.reset(new DataExtractor(Data, Module->isLittleEndian(),
+ Module->getBytesInAddress()));
+ OpdAddress = Section->getAddress();
+ }
+ break;
+ }
+ }
+ }
+ std::vector<std::pair<SymbolRef, uint64_t>> Symbols =
+ computeSymbolSizes(*Module);
+ for (auto &P : Symbols)
+ addSymbol(P.first, P.second, OpdExtractor.get(), OpdAddress);
+
+ // If this is a COFF object and we didn't find any symbols, try the export
+ // table.
+ if (Symbols.empty()) {
+ if (auto *CoffObj = dyn_cast<COFFObjectFile>(Obj))
+ addCoffExportSymbols(CoffObj);
+ }
+}
+
+namespace {
+struct OffsetNamePair {
+ uint32_t Offset;
+ StringRef Name;
+ bool operator<(const OffsetNamePair &R) const {
+ return Offset < R.Offset;
+ }
+};
+}
+
+void ModuleInfo::addCoffExportSymbols(const COFFObjectFile *CoffObj) {
+ // Get all export names and offsets.
+ std::vector<OffsetNamePair> ExportSyms;
+ for (const ExportDirectoryEntryRef &Ref : CoffObj->export_directories()) {
+ StringRef Name;
+ uint32_t Offset;
+ if (error(Ref.getSymbolName(Name)) || error(Ref.getExportRVA(Offset)))
+ return;
+ ExportSyms.push_back(OffsetNamePair{Offset, Name});
+ }
+ if (ExportSyms.empty())
+ return;
+
+ // Sort by ascending offset.
+ array_pod_sort(ExportSyms.begin(), ExportSyms.end());
+
+ // Approximate the symbol sizes by assuming they run to the next symbol.
+ // FIXME: This assumes all exports are functions.
+ uint64_t ImageBase = CoffObj->getImageBase();
+ for (auto I = ExportSyms.begin(), E = ExportSyms.end(); I != E; ++I) {
+ OffsetNamePair &Export = *I;
+ // FIXME: The last export has a one byte size now.
+ uint32_t NextOffset = I != E ? I->Offset : Export.Offset + 1;
+ uint64_t SymbolStart = ImageBase + Export.Offset;
+ uint64_t SymbolSize = NextOffset - Export.Offset;
+ SymbolDesc SD = {SymbolStart, SymbolSize};
+ Functions.insert(std::make_pair(SD, Export.Name));
+ }
+}
+
+void ModuleInfo::addSymbol(const SymbolRef &Symbol, uint64_t SymbolSize,
+ DataExtractor *OpdExtractor, uint64_t OpdAddress) {
+ SymbolRef::Type SymbolType = Symbol.getType();
+ if (SymbolType != SymbolRef::ST_Function && SymbolType != SymbolRef::ST_Data)
+ return;
+ ErrorOr<uint64_t> SymbolAddressOrErr = Symbol.getAddress();
+ if (error(SymbolAddressOrErr.getError()))
+ return;
+ uint64_t SymbolAddress = *SymbolAddressOrErr;
+ if (OpdExtractor) {
+ // For big-endian PowerPC64 ELF, symbols in the .opd section refer to
+ // function descriptors. The first word of the descriptor is a pointer to
+ // the function's code.
+ // For the purposes of symbolization, pretend the symbol's address is that
+ // of the function's code, not the descriptor.
+ uint64_t OpdOffset = SymbolAddress - OpdAddress;
+ uint32_t OpdOffset32 = OpdOffset;
+ if (OpdOffset == OpdOffset32 &&
+ OpdExtractor->isValidOffsetForAddress(OpdOffset32))
+ SymbolAddress = OpdExtractor->getAddress(&OpdOffset32);
+ }
+ ErrorOr<StringRef> SymbolNameOrErr = Symbol.getName();
+ if (error(SymbolNameOrErr.getError()))
+ return;
+ StringRef SymbolName = *SymbolNameOrErr;
+ // Mach-O symbol table names have leading underscore, skip it.
+ if (Module->isMachO() && SymbolName.size() > 0 && SymbolName[0] == '_')
+ SymbolName = SymbolName.drop_front();
+ // FIXME: If a function has alias, there are two entries in symbol table
+ // with same address size. Make sure we choose the correct one.
+ auto &M = SymbolType == SymbolRef::ST_Function ? Functions : Objects;
+ SymbolDesc SD = { SymbolAddress, SymbolSize };
+ M.insert(std::make_pair(SD, SymbolName));
+}
+
+// Return true if this is a 32-bit x86 PE COFF module.
+bool ModuleInfo::isWin32Module() const {
+ auto *CoffObject = dyn_cast<COFFObjectFile>(Module);
+ return CoffObject && CoffObject->getMachine() == COFF::IMAGE_FILE_MACHINE_I386;
+}
+
+uint64_t ModuleInfo::getModulePreferredBase() const {
+ if (auto *CoffObject = dyn_cast<COFFObjectFile>(Module))
+ return CoffObject->getImageBase();
+ return 0;
+}
+
+bool ModuleInfo::getNameFromSymbolTable(SymbolRef::Type Type, uint64_t Address,
+ std::string &Name, uint64_t &Addr,
+ uint64_t &Size) const {
+ const auto &SymbolMap = Type == SymbolRef::ST_Function ? Functions : Objects;
+ if (SymbolMap.empty())
+ return false;
+ SymbolDesc SD = { Address, Address };
+ auto SymbolIterator = SymbolMap.upper_bound(SD);
+ if (SymbolIterator == SymbolMap.begin())
+ return false;
+ --SymbolIterator;
+ if (SymbolIterator->first.Size != 0 &&
+ SymbolIterator->first.Addr + SymbolIterator->first.Size <= Address)
+ return false;
+ Name = SymbolIterator->second.str();
+ Addr = SymbolIterator->first.Addr;
+ Size = SymbolIterator->first.Size;
+ return true;
+}
+
+DILineInfo ModuleInfo::symbolizeCode(
+ uint64_t ModuleOffset, const LLVMSymbolizer::Options &Opts) const {
+ DILineInfo LineInfo;
+ if (DebugInfoContext) {
+ LineInfo = DebugInfoContext->getLineInfoForAddress(
+ ModuleOffset, getDILineInfoSpecifier(Opts));
+ }
+ // Override function name from symbol table if necessary.
+ if (Opts.PrintFunctions != FunctionNameKind::None && Opts.UseSymbolTable) {
+ std::string FunctionName;
+ uint64_t Start, Size;
+ if (getNameFromSymbolTable(SymbolRef::ST_Function, ModuleOffset,
+ FunctionName, Start, Size)) {
+ LineInfo.FunctionName = FunctionName;
+ }
+ }
+ return LineInfo;
+}
+
+DIInliningInfo ModuleInfo::symbolizeInlinedCode(
+ uint64_t ModuleOffset, const LLVMSymbolizer::Options &Opts) const {
+ DIInliningInfo InlinedContext;
+
+ if (DebugInfoContext) {
+ InlinedContext = DebugInfoContext->getInliningInfoForAddress(
+ ModuleOffset, getDILineInfoSpecifier(Opts));
+ }
+ // Make sure there is at least one frame in context.
+ if (InlinedContext.getNumberOfFrames() == 0) {
+ InlinedContext.addFrame(DILineInfo());
+ }
+ // Override the function name in lower frame with name from symbol table.
+ if (Opts.PrintFunctions != FunctionNameKind::None && Opts.UseSymbolTable) {
+ DIInliningInfo PatchedInlinedContext;
+ for (uint32_t i = 0, n = InlinedContext.getNumberOfFrames(); i < n; i++) {
+ DILineInfo LineInfo = InlinedContext.getFrame(i);
+ if (i == n - 1) {
+ std::string FunctionName;
+ uint64_t Start, Size;
+ if (getNameFromSymbolTable(SymbolRef::ST_Function, ModuleOffset,
+ FunctionName, Start, Size)) {
+ LineInfo.FunctionName = FunctionName;
+ }
+ }
+ PatchedInlinedContext.addFrame(LineInfo);
+ }
+ InlinedContext = PatchedInlinedContext;
+ }
+ return InlinedContext;
+}
+
+bool ModuleInfo::symbolizeData(uint64_t ModuleOffset, std::string &Name,
+ uint64_t &Start, uint64_t &Size) const {
+ return getNameFromSymbolTable(SymbolRef::ST_Data, ModuleOffset, Name, Start,
+ Size);
+}
+
+const char LLVMSymbolizer::kBadString[] = "??";
+
+std::string LLVMSymbolizer::symbolizeCode(const std::string &ModuleName,
+ uint64_t ModuleOffset) {
+ ModuleInfo *Info = getOrCreateModuleInfo(ModuleName);
+ if (!Info)
+ return printDILineInfo(DILineInfo(), Info);
+
+ // If the user is giving us relative addresses, add the preferred base of the
+ // object to the offset before we do the query. It's what DIContext expects.
+ if (Opts.RelativeAddresses)
+ ModuleOffset += Info->getModulePreferredBase();
+
+ if (Opts.PrintInlining) {
+ DIInliningInfo InlinedContext =
+ Info->symbolizeInlinedCode(ModuleOffset, Opts);
+ uint32_t FramesNum = InlinedContext.getNumberOfFrames();
+ assert(FramesNum > 0);
+ std::string Result;
+ for (uint32_t i = 0; i < FramesNum; i++) {
+ DILineInfo LineInfo = InlinedContext.getFrame(i);
+ Result += printDILineInfo(LineInfo, Info);
+ }
+ return Result;
+ }
+ DILineInfo LineInfo = Info->symbolizeCode(ModuleOffset, Opts);
+ return printDILineInfo(LineInfo, Info);
+}
+
+std::string LLVMSymbolizer::symbolizeData(const std::string &ModuleName,
+ uint64_t ModuleOffset) {
+ std::string Name = kBadString;
+ uint64_t Start = 0;
+ uint64_t Size = 0;
+ if (Opts.UseSymbolTable) {
+ if (ModuleInfo *Info = getOrCreateModuleInfo(ModuleName)) {
+ // If the user is giving us relative addresses, add the preferred base of the
+ // object to the offset before we do the query. It's what DIContext expects.
+ if (Opts.RelativeAddresses)
+ ModuleOffset += Info->getModulePreferredBase();
+ if (Info->symbolizeData(ModuleOffset, Name, Start, Size) && Opts.Demangle)
+ Name = DemangleName(Name, Info);
+ }
+ }
+ std::stringstream ss;
+ ss << Name << "\n" << Start << " " << Size << "\n";
+ return ss.str();
+}
+
+void LLVMSymbolizer::flush() {
+ DeleteContainerSeconds(Modules);
+ ObjectPairForPathArch.clear();
+ ObjectFileForArch.clear();
+}
+
+// For Path="/path/to/foo" and Basename="foo" assume that debug info is in
+// /path/to/foo.dSYM/Contents/Resources/DWARF/foo.
+// For Path="/path/to/bar.dSYM" and Basename="foo" assume that debug info is in
+// /path/to/bar.dSYM/Contents/Resources/DWARF/foo.
+static
+std::string getDarwinDWARFResourceForPath(
+ const std::string &Path, const std::string &Basename) {
+ SmallString<16> ResourceName = StringRef(Path);
+ if (sys::path::extension(Path) != ".dSYM") {
+ ResourceName += ".dSYM";
+ }
+ sys::path::append(ResourceName, "Contents", "Resources", "DWARF");
+ sys::path::append(ResourceName, Basename);
+ return ResourceName.str();
+}
+
+static bool checkFileCRC(StringRef Path, uint32_t CRCHash) {
+ ErrorOr<std::unique_ptr<MemoryBuffer>> MB =
+ MemoryBuffer::getFileOrSTDIN(Path);
+ if (!MB)
+ return false;
+ return !zlib::isAvailable() || CRCHash == zlib::crc32(MB.get()->getBuffer());
+}
+
+static bool findDebugBinary(const std::string &OrigPath,
+ const std::string &DebuglinkName, uint32_t CRCHash,
+ std::string &Result) {
+ std::string OrigRealPath = OrigPath;
+#if defined(HAVE_REALPATH)
+ if (char *RP = realpath(OrigPath.c_str(), nullptr)) {
+ OrigRealPath = RP;
+ free(RP);
+ }
+#endif
+ SmallString<16> OrigDir(OrigRealPath);
+ llvm::sys::path::remove_filename(OrigDir);
+ SmallString<16> DebugPath = OrigDir;
+ // Try /path/to/original_binary/debuglink_name
+ llvm::sys::path::append(DebugPath, DebuglinkName);
+ if (checkFileCRC(DebugPath, CRCHash)) {
+ Result = DebugPath.str();
+ return true;
+ }
+ // Try /path/to/original_binary/.debug/debuglink_name
+ DebugPath = OrigRealPath;
+ llvm::sys::path::append(DebugPath, ".debug", DebuglinkName);
+ if (checkFileCRC(DebugPath, CRCHash)) {
+ Result = DebugPath.str();
+ return true;
+ }
+ // Try /usr/lib/debug/path/to/original_binary/debuglink_name
+ DebugPath = "/usr/lib/debug";
+ llvm::sys::path::append(DebugPath, llvm::sys::path::relative_path(OrigDir),
+ DebuglinkName);
+ if (checkFileCRC(DebugPath, CRCHash)) {
+ Result = DebugPath.str();
+ return true;
+ }
+ return false;
+}
+
+static bool getGNUDebuglinkContents(const ObjectFile *Obj, std::string &DebugName,
+ uint32_t &CRCHash) {
+ if (!Obj)
+ return false;
+ for (const SectionRef &Section : Obj->sections()) {
+ StringRef Name;
+ Section.getName(Name);
+ Name = Name.substr(Name.find_first_not_of("._"));
+ if (Name == "gnu_debuglink") {
+ StringRef Data;
+ Section.getContents(Data);
+ DataExtractor DE(Data, Obj->isLittleEndian(), 0);
+ uint32_t Offset = 0;
+ if (const char *DebugNameStr = DE.getCStr(&Offset)) {
+ // 4-byte align the offset.
+ Offset = (Offset + 3) & ~0x3;
+ if (DE.isValidOffsetForDataOfSize(Offset, 4)) {
+ DebugName = DebugNameStr;
+ CRCHash = DE.getU32(&Offset);
+ return true;
+ }
+ }
+ break;
+ }
+ }
+ return false;
+}
+
+static
+bool darwinDsymMatchesBinary(const MachOObjectFile *DbgObj,
+ const MachOObjectFile *Obj) {
+ ArrayRef<uint8_t> dbg_uuid = DbgObj->getUuid();
+ ArrayRef<uint8_t> bin_uuid = Obj->getUuid();
+ if (dbg_uuid.empty() || bin_uuid.empty())
+ return false;
+ return !memcmp(dbg_uuid.data(), bin_uuid.data(), dbg_uuid.size());
+}
+
+ObjectFile *LLVMSymbolizer::lookUpDsymFile(const std::string &ExePath,
+ const MachOObjectFile *MachExeObj, const std::string &ArchName) {
+ // On Darwin we may find DWARF in separate object file in
+ // resource directory.
+ std::vector<std::string> DsymPaths;
+ StringRef Filename = sys::path::filename(ExePath);
+ DsymPaths.push_back(getDarwinDWARFResourceForPath(ExePath, Filename));
+ for (const auto &Path : Opts.DsymHints) {
+ DsymPaths.push_back(getDarwinDWARFResourceForPath(Path, Filename));
+ }
+ for (const auto &path : DsymPaths) {
+ ErrorOr<OwningBinary<Binary>> BinaryOrErr = createBinary(path);
+ std::error_code EC = BinaryOrErr.getError();
+ if (EC != errc::no_such_file_or_directory && !error(EC)) {
+ OwningBinary<Binary> B = std::move(BinaryOrErr.get());
+ ObjectFile *DbgObj =
+ getObjectFileFromBinary(B.getBinary(), ArchName);
+ const MachOObjectFile *MachDbgObj =
+ dyn_cast<const MachOObjectFile>(DbgObj);
+ if (!MachDbgObj) continue;
+ if (darwinDsymMatchesBinary(MachDbgObj, MachExeObj)) {
+ addOwningBinary(std::move(B));
+ return DbgObj;
+ }
+ }
+ }
+ return nullptr;
+}
+
+LLVMSymbolizer::ObjectPair
+LLVMSymbolizer::getOrCreateObjects(const std::string &Path,
+ const std::string &ArchName) {
+ const auto &I = ObjectPairForPathArch.find(std::make_pair(Path, ArchName));
+ if (I != ObjectPairForPathArch.end())
+ return I->second;
+ ObjectFile *Obj = nullptr;
+ ObjectFile *DbgObj = nullptr;
+ ErrorOr<OwningBinary<Binary>> BinaryOrErr = createBinary(Path);
+ if (!error(BinaryOrErr.getError())) {
+ OwningBinary<Binary> &B = BinaryOrErr.get();
+ Obj = getObjectFileFromBinary(B.getBinary(), ArchName);
+ if (!Obj) {
+ ObjectPair Res = std::make_pair(nullptr, nullptr);
+ ObjectPairForPathArch[std::make_pair(Path, ArchName)] = Res;
+ return Res;
+ }
+ addOwningBinary(std::move(B));
+ if (auto MachObj = dyn_cast<const MachOObjectFile>(Obj))
+ DbgObj = lookUpDsymFile(Path, MachObj, ArchName);
+ // Try to locate the debug binary using .gnu_debuglink section.
+ if (!DbgObj) {
+ std::string DebuglinkName;
+ uint32_t CRCHash;
+ std::string DebugBinaryPath;
+ if (getGNUDebuglinkContents(Obj, DebuglinkName, CRCHash) &&
+ findDebugBinary(Path, DebuglinkName, CRCHash, DebugBinaryPath)) {
+ BinaryOrErr = createBinary(DebugBinaryPath);
+ if (!error(BinaryOrErr.getError())) {
+ OwningBinary<Binary> B = std::move(BinaryOrErr.get());
+ DbgObj = getObjectFileFromBinary(B.getBinary(), ArchName);
+ addOwningBinary(std::move(B));
+ }
+ }
+ }
+ }
+ if (!DbgObj)
+ DbgObj = Obj;
+ ObjectPair Res = std::make_pair(Obj, DbgObj);
+ ObjectPairForPathArch[std::make_pair(Path, ArchName)] = Res;
+ return Res;
+}
+
+ObjectFile *
+LLVMSymbolizer::getObjectFileFromBinary(Binary *Bin,
+ const std::string &ArchName) {
+ if (!Bin)
+ return nullptr;
+ ObjectFile *Res = nullptr;
+ if (MachOUniversalBinary *UB = dyn_cast<MachOUniversalBinary>(Bin)) {
+ const auto &I = ObjectFileForArch.find(
+ std::make_pair(UB, ArchName));
+ if (I != ObjectFileForArch.end())
+ return I->second;
+ ErrorOr<std::unique_ptr<ObjectFile>> ParsedObj =
+ UB->getObjectForArch(ArchName);
+ if (ParsedObj) {
+ Res = ParsedObj.get().get();
+ ParsedBinariesAndObjects.push_back(std::move(ParsedObj.get()));
+ }
+ ObjectFileForArch[std::make_pair(UB, ArchName)] = Res;
+ } else if (Bin->isObject()) {
+ Res = cast<ObjectFile>(Bin);
+ }
+ return Res;
+}
+
+ModuleInfo *
+LLVMSymbolizer::getOrCreateModuleInfo(const std::string &ModuleName) {
+ const auto &I = Modules.find(ModuleName);
+ if (I != Modules.end())
+ return I->second;
+ std::string BinaryName = ModuleName;
+ std::string ArchName = Opts.DefaultArch;
+ size_t ColonPos = ModuleName.find_last_of(':');
+ // Verify that substring after colon form a valid arch name.
+ if (ColonPos != std::string::npos) {
+ std::string ArchStr = ModuleName.substr(ColonPos + 1);
+ if (Triple(ArchStr).getArch() != Triple::UnknownArch) {
+ BinaryName = ModuleName.substr(0, ColonPos);
+ ArchName = ArchStr;
+ }
+ }
+ ObjectPair Objects = getOrCreateObjects(BinaryName, ArchName);
+
+ if (!Objects.first) {
+ // Failed to find valid object file.
+ Modules.insert(make_pair(ModuleName, (ModuleInfo *)nullptr));
+ return nullptr;
+ }
+ DIContext *Context = nullptr;
+ if (auto CoffObject = dyn_cast<COFFObjectFile>(Objects.first)) {
+ // If this is a COFF object, assume it contains PDB debug information. If
+ // we don't find any we will fall back to the DWARF case.
+ std::unique_ptr<IPDBSession> Session;
+ PDB_ErrorCode Error = loadDataForEXE(PDB_ReaderType::DIA,
+ Objects.first->getFileName(), Session);
+ if (Error == PDB_ErrorCode::Success) {
+ Context = new PDBContext(*CoffObject, std::move(Session));
+ }
+ }
+ if (!Context)
+ Context = new DWARFContextInMemory(*Objects.second);
+ assert(Context);
+ ModuleInfo *Info = new ModuleInfo(Objects.first, Context);
+ Modules.insert(make_pair(ModuleName, Info));
+ return Info;
+}
+
+std::string LLVMSymbolizer::printDILineInfo(DILineInfo LineInfo,
+ ModuleInfo *ModInfo) const {
+ // By default, DILineInfo contains "<invalid>" for function/filename it
+ // cannot fetch. We replace it to "??" to make our output closer to addr2line.
+ static const std::string kDILineInfoBadString = "<invalid>";
+ std::stringstream Result;
+ if (Opts.PrintFunctions != FunctionNameKind::None) {
+ std::string FunctionName = LineInfo.FunctionName;
+ if (FunctionName == kDILineInfoBadString)
+ FunctionName = kBadString;
+ else if (Opts.Demangle)
+ FunctionName = DemangleName(FunctionName, ModInfo);
+ Result << FunctionName << "\n";
+ }
+ std::string Filename = LineInfo.FileName;
+ if (Filename == kDILineInfoBadString)
+ Filename = kBadString;
+ Result << Filename << ":" << LineInfo.Line << ":" << LineInfo.Column << "\n";
+ return Result.str();
+}
+
+// Undo these various manglings for Win32 extern "C" functions:
+// cdecl - _foo
+// stdcall - _foo@12
+// fastcall - @foo@12
+// vectorcall - foo@@12
+// These are all different linkage names for 'foo'.
+static StringRef demanglePE32ExternCFunc(StringRef SymbolName) {
+ // Remove any '_' or '@' prefix.
+ char Front = SymbolName.empty() ? '\0' : SymbolName[0];
+ if (Front == '_' || Front == '@')
+ SymbolName = SymbolName.drop_front();
+
+ // Remove any '@[0-9]+' suffix.
+ if (Front != '?') {
+ size_t AtPos = SymbolName.rfind('@');
+ if (AtPos != StringRef::npos &&
+ std::all_of(SymbolName.begin() + AtPos + 1, SymbolName.end(),
+ [](char C) { return C >= '0' && C <= '9'; })) {
+ SymbolName = SymbolName.substr(0, AtPos);
+ }
+ }
+
+ // Remove any ending '@' for vectorcall.
+ if (SymbolName.endswith("@"))
+ SymbolName = SymbolName.drop_back();
+
+ return SymbolName;
+}
+
+#if !defined(_MSC_VER)
+// Assume that __cxa_demangle is provided by libcxxabi (except for Windows).
+extern "C" char *__cxa_demangle(const char *mangled_name, char *output_buffer,
+ size_t *length, int *status);
+#endif
+
+std::string LLVMSymbolizer::DemangleName(const std::string &Name,
+ ModuleInfo *ModInfo) {
+#if !defined(_MSC_VER)
+ // We can spoil names of symbols with C linkage, so use an heuristic
+ // approach to check if the name should be demangled.
+ if (Name.substr(0, 2) == "_Z") {
+ int status = 0;
+ char *DemangledName = __cxa_demangle(Name.c_str(), nullptr, nullptr, &status);
+ if (status != 0)
+ return Name;
+ std::string Result = DemangledName;
+ free(DemangledName);
+ return Result;
+ }
+#else
+ if (!Name.empty() && Name.front() == '?') {
+ // Only do MSVC C++ demangling on symbols starting with '?'.
+ char DemangledName[1024] = {0};
+ DWORD result = ::UnDecorateSymbolName(
+ Name.c_str(), DemangledName, 1023,
+ UNDNAME_NO_ACCESS_SPECIFIERS | // Strip public, private, protected
+ UNDNAME_NO_ALLOCATION_LANGUAGE | // Strip __thiscall, __stdcall, etc
+ UNDNAME_NO_THROW_SIGNATURES | // Strip throw() specifications
+ UNDNAME_NO_MEMBER_TYPE | // Strip virtual, static, etc specifiers
+ UNDNAME_NO_MS_KEYWORDS | // Strip all MS extension keywords
+ UNDNAME_NO_FUNCTION_RETURNS); // Strip function return types
+ return (result == 0) ? Name : std::string(DemangledName);
+ }
+#endif
+ if (ModInfo->isWin32Module())
+ return std::string(demanglePE32ExternCFunc(Name));
+ return Name;
+}
+
+} // namespace symbolize
+} // namespace llvm