1 //===- tools/dsymutil/MachODebugMapParser.cpp - Parse STABS debug maps ----===//
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "BinaryHolder.h"
13 #include "llvm/Object/MachO.h"
14 #include "llvm/Support/Path.h"
15 #include "llvm/Support/raw_ostream.h"
19 using namespace llvm::dsymutil;
20 using namespace llvm::object;
22 class MachODebugMapParser {
24 MachODebugMapParser(StringRef BinaryPath, ArrayRef<std::string> Archs,
25 StringRef PathPrefix = "", bool Verbose = false)
26 : BinaryPath(BinaryPath), Archs(Archs.begin(), Archs.end()),
27 PathPrefix(PathPrefix), MainBinaryHolder(Verbose),
28 CurrentObjectHolder(Verbose), CurrentDebugMapObject(nullptr) {}
30 /// \brief Parses and returns the DebugMaps of the input binary.
31 /// The binary contains multiple maps in case it is a universal
33 /// \returns an error in case the provided BinaryPath doesn't exist
34 /// or isn't of a supported type.
35 ErrorOr<std::vector<std::unique_ptr<DebugMap>>> parse();
38 std::string BinaryPath;
39 SmallVector<StringRef, 1> Archs;
40 std::string PathPrefix;
42 /// Owns the MemoryBuffer for the main binary.
43 BinaryHolder MainBinaryHolder;
44 /// Map of the binary symbol addresses.
45 StringMap<uint64_t> MainBinarySymbolAddresses;
46 StringRef MainBinaryStrings;
47 /// The constructed DebugMap.
48 std::unique_ptr<DebugMap> Result;
50 /// Owns the MemoryBuffer for the currently handled object file.
51 BinaryHolder CurrentObjectHolder;
52 /// Map of the currently processed object file symbol addresses.
53 StringMap<uint64_t> CurrentObjectAddresses;
54 /// Element of the debug map corresponfing to the current object file.
55 DebugMapObject *CurrentDebugMapObject;
57 /// Holds function info while function scope processing.
58 const char *CurrentFunctionName;
59 uint64_t CurrentFunctionAddress;
61 std::unique_ptr<DebugMap> parseOneBinary(const MachOObjectFile &MainBinary,
62 StringRef BinaryPath);
64 void switchToNewDebugMapObject(StringRef Filename, sys::TimeValue Timestamp);
65 void resetParserState();
66 uint64_t getMainBinarySymbolAddress(StringRef Name);
67 void loadMainBinarySymbols(const MachOObjectFile &MainBinary);
68 void loadCurrentObjectFileSymbols(const object::MachOObjectFile &Obj);
69 void handleStabSymbolTableEntry(uint32_t StringIndex, uint8_t Type,
70 uint8_t SectionIndex, uint16_t Flags,
73 template <typename STEType> void handleStabDebugMapEntry(const STEType &STE) {
74 handleStabSymbolTableEntry(STE.n_strx, STE.n_type, STE.n_sect, STE.n_desc,
79 static void Warning(const Twine &Msg) { errs() << "warning: " + Msg + "\n"; }
82 /// Reset the parser state coresponding to the current object
83 /// file. This is to be called after an object file is finished
85 void MachODebugMapParser::resetParserState() {
86 CurrentObjectAddresses.clear();
87 CurrentDebugMapObject = nullptr;
90 /// Create a new DebugMapObject. This function resets the state of the
91 /// parser that was referring to the last object file and sets
92 /// everything up to add symbols to the new one.
93 void MachODebugMapParser::switchToNewDebugMapObject(StringRef Filename,
94 sys::TimeValue Timestamp) {
97 SmallString<80> Path(PathPrefix);
98 sys::path::append(Path, Filename);
101 CurrentObjectHolder.GetFilesAs<MachOObjectFile>(Path, Timestamp);
102 if (auto Error = MachOOrError.getError()) {
103 Warning(Twine("cannot open debug object \"") + Path.str() + "\": " +
104 Error.message() + "\n");
109 CurrentObjectHolder.GetAs<MachOObjectFile>(Result->getTriple());
110 if (auto Err = ErrOrAchObj.getError()) {
111 return Warning(Twine("cannot open debug object \"") + Path.str() + "\": " +
112 Err.message() + "\n");
115 CurrentDebugMapObject = &Result->addDebugMapObject(Path, Timestamp);
116 loadCurrentObjectFileSymbols(*ErrOrAchObj);
119 std::unique_ptr<DebugMap>
120 MachODebugMapParser::parseOneBinary(const MachOObjectFile &MainBinary,
121 StringRef BinaryPath) {
122 loadMainBinarySymbols(MainBinary);
123 Result = make_unique<DebugMap>(BinaryHolder::getTriple(MainBinary));
124 MainBinaryStrings = MainBinary.getStringTableData();
125 for (const SymbolRef &Symbol : MainBinary.symbols()) {
126 const DataRefImpl &DRI = Symbol.getRawDataRefImpl();
127 if (MainBinary.is64Bit())
128 handleStabDebugMapEntry(MainBinary.getSymbol64TableEntry(DRI));
130 handleStabDebugMapEntry(MainBinary.getSymbolTableEntry(DRI));
134 return std::move(Result);
137 static bool shouldLinkArch(SmallVectorImpl<StringRef> &Archs, StringRef Arch) {
139 std::find(Archs.begin(), Archs.end(), "all") != Archs.end() ||
140 std::find(Archs.begin(), Archs.end(), "*") != Archs.end())
143 if (Arch.startswith("arm") && Arch != "arm64" &&
144 std::find(Archs.begin(), Archs.end(), "arm") != Archs.end())
147 return std::find(Archs.begin(), Archs.end(), Arch) != Archs.end();
150 /// This main parsing routine tries to open the main binary and if
151 /// successful iterates over the STAB entries. The real parsing is
152 /// done in handleStabSymbolTableEntry.
153 ErrorOr<std::vector<std::unique_ptr<DebugMap>>> MachODebugMapParser::parse() {
154 auto MainBinOrError =
155 MainBinaryHolder.GetFilesAs<MachOObjectFile>(BinaryPath);
156 if (auto Error = MainBinOrError.getError())
159 std::vector<std::unique_ptr<DebugMap>> Results;
161 for (const auto *Binary : *MainBinOrError)
162 if (shouldLinkArch(Archs, Binary->getArch(nullptr, &T).getArchName()))
163 Results.push_back(parseOneBinary(*Binary, BinaryPath));
165 return std::move(Results);
168 /// Interpret the STAB entries to fill the DebugMap.
169 void MachODebugMapParser::handleStabSymbolTableEntry(uint32_t StringIndex,
171 uint8_t SectionIndex,
174 if (!(Type & MachO::N_STAB))
177 const char *Name = &MainBinaryStrings.data()[StringIndex];
179 // An N_OSO entry represents the start of a new object file description.
180 if (Type == MachO::N_OSO) {
181 sys::TimeValue Timestamp;
182 Timestamp.fromEpochTime(Value);
183 return switchToNewDebugMapObject(Name, Timestamp);
186 // If the last N_OSO object file wasn't found,
187 // CurrentDebugMapObject will be null. Do not update anything
188 // until we find the next valid N_OSO entry.
189 if (!CurrentDebugMapObject)
195 // This is a global variable. We need to query the main binary
196 // symbol table to find its address as it might not be in the
197 // debug map (for common symbols).
198 Value = getMainBinarySymbolAddress(Name);
201 // Functions are scopes in STABS. They have an end marker that
202 // contains the function size.
203 if (Name[0] == '\0') {
205 Value = CurrentFunctionAddress;
206 Name = CurrentFunctionName;
209 CurrentFunctionName = Name;
210 CurrentFunctionAddress = Value;
219 auto ObjectSymIt = CurrentObjectAddresses.find(Name);
220 if (ObjectSymIt == CurrentObjectAddresses.end())
221 return Warning("could not find object file symbol for symbol " +
223 if (!CurrentDebugMapObject->addSymbol(Name, ObjectSymIt->getValue(), Value,
225 return Warning(Twine("failed to insert symbol '") + Name +
226 "' in the debug map.");
229 /// Load the current object file symbols into CurrentObjectAddresses.
230 void MachODebugMapParser::loadCurrentObjectFileSymbols(
231 const object::MachOObjectFile &Obj) {
232 CurrentObjectAddresses.clear();
234 for (auto Sym : Obj.symbols()) {
235 uint64_t Addr = Sym.getValue();
236 ErrorOr<StringRef> Name = Sym.getName();
239 CurrentObjectAddresses[*Name] = Addr;
243 /// Lookup a symbol address in the main binary symbol table. The
244 /// parser only needs to query common symbols, thus not every symbol's
245 /// address is available through this function.
246 uint64_t MachODebugMapParser::getMainBinarySymbolAddress(StringRef Name) {
247 auto Sym = MainBinarySymbolAddresses.find(Name);
248 if (Sym == MainBinarySymbolAddresses.end())
253 /// Load the interesting main binary symbols' addresses into
254 /// MainBinarySymbolAddresses.
255 void MachODebugMapParser::loadMainBinarySymbols(
256 const MachOObjectFile &MainBinary) {
257 section_iterator Section = MainBinary.section_end();
258 MainBinarySymbolAddresses.clear();
259 for (const auto &Sym : MainBinary.symbols()) {
260 SymbolRef::Type Type = Sym.getType();
261 // Skip undefined and STAB entries.
262 if ((Type & SymbolRef::ST_Debug) || (Type & SymbolRef::ST_Unknown))
264 // The only symbols of interest are the global variables. These
265 // are the only ones that need to be queried because the address
266 // of common data won't be described in the debug map. All other
267 // addresses should be fetched for the debug map.
268 if (!(Sym.getFlags() & SymbolRef::SF_Global))
270 ErrorOr<section_iterator> SectionOrErr = Sym.getSection();
273 Section = *SectionOrErr;
274 if (Section == MainBinary.section_end() || Section->isText())
276 uint64_t Addr = Sym.getValue();
277 ErrorOr<StringRef> NameOrErr = Sym.getName();
280 StringRef Name = *NameOrErr;
281 if (Name.size() == 0 || Name[0] == '\0')
283 MainBinarySymbolAddresses[Name] = Addr;
289 llvm::ErrorOr<std::vector<std::unique_ptr<DebugMap>>>
290 parseDebugMap(StringRef InputFile, ArrayRef<std::string> Archs,
291 StringRef PrependPath, bool Verbose, bool InputIsYAML) {
293 MachODebugMapParser Parser(InputFile, Archs, PrependPath, Verbose);
294 return Parser.parse();
296 return DebugMap::parseYAMLDebugMap(InputFile, PrependPath, Verbose);