1 //===-- LLVMSymbolize.cpp -------------------------------------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Implementation for LLVM symbolization library.
12 //===----------------------------------------------------------------------===//
14 #include "LLVMSymbolize.h"
15 #include "llvm/ADT/STLExtras.h"
16 #include "llvm/Object/MachO.h"
17 #include "llvm/Support/Casting.h"
18 #include "llvm/Support/FileSystem.h"
19 #include "llvm/Support/Path.h"
26 static bool error(error_code ec) {
29 errs() << "LLVMSymbolizer: error reading file: " << ec.message() << ".\n";
34 getDILineInfoSpecifierFlags(const LLVMSymbolizer::Options &Opts) {
35 uint32_t Flags = llvm::DILineInfoSpecifier::FileLineInfo |
36 llvm::DILineInfoSpecifier::AbsoluteFilePath;
37 if (Opts.PrintFunctions)
38 Flags |= llvm::DILineInfoSpecifier::FunctionName;
42 static void patchFunctionNameInDILineInfo(const std::string &NewFunctionName,
43 DILineInfo &LineInfo) {
44 std::string FileName = LineInfo.getFileName();
45 LineInfo = DILineInfo(StringRef(FileName), StringRef(NewFunctionName),
46 LineInfo.getLine(), LineInfo.getColumn());
49 ModuleInfo::ModuleInfo(ObjectFile *Obj, DIContext *DICtx)
50 : Module(Obj), DebugInfoContext(DICtx) {
52 for (symbol_iterator si = Module->begin_symbols(), se = Module->end_symbols();
53 si != se; si.increment(ec)) {
56 SymbolRef::Type SymbolType;
57 if (error(si->getType(SymbolType)))
59 if (SymbolType != SymbolRef::ST_Function &&
60 SymbolType != SymbolRef::ST_Data)
62 uint64_t SymbolAddress;
63 if (error(si->getAddress(SymbolAddress)) ||
64 SymbolAddress == UnknownAddressOrSize)
67 // Getting symbol size is linear for Mach-O files, so assume that symbol
68 // occupies the memory range up to the following symbol.
69 if (isa<MachOObjectFile>(Obj))
71 else if (error(si->getSize(SymbolSize)) ||
72 SymbolSize == UnknownAddressOrSize)
75 if (error(si->getName(SymbolName)))
77 // FIXME: If a function has alias, there are two entries in symbol table
78 // with same address size. Make sure we choose the correct one.
79 SymbolMapTy &M = SymbolType == SymbolRef::ST_Function ? Functions : Objects;
80 SymbolDesc SD = { SymbolAddress, SymbolSize };
81 M.insert(std::make_pair(SD, SymbolName));
85 bool ModuleInfo::getNameFromSymbolTable(SymbolRef::Type Type, uint64_t Address,
86 std::string &Name, uint64_t &Addr,
87 uint64_t &Size) const {
88 const SymbolMapTy &M = Type == SymbolRef::ST_Function ? Functions : Objects;
91 SymbolDesc SD = { Address, Address };
92 SymbolMapTy::const_iterator it = M.upper_bound(SD);
96 if (it->first.Size != 0 && it->first.Addr + it->first.Size <= Address)
98 Name = it->second.str();
99 Addr = it->first.Addr;
100 Size = it->first.Size;
104 DILineInfo ModuleInfo::symbolizeCode(
105 uint64_t ModuleOffset, const LLVMSymbolizer::Options &Opts) const {
107 if (DebugInfoContext) {
108 LineInfo = DebugInfoContext->getLineInfoForAddress(
109 ModuleOffset, getDILineInfoSpecifierFlags(Opts));
111 // Override function name from symbol table if necessary.
112 if (Opts.PrintFunctions && Opts.UseSymbolTable) {
113 std::string FunctionName;
114 uint64_t Start, Size;
115 if (getNameFromSymbolTable(SymbolRef::ST_Function, ModuleOffset,
116 FunctionName, Start, Size)) {
117 patchFunctionNameInDILineInfo(FunctionName, LineInfo);
123 DIInliningInfo ModuleInfo::symbolizeInlinedCode(
124 uint64_t ModuleOffset, const LLVMSymbolizer::Options &Opts) const {
125 DIInliningInfo InlinedContext;
126 if (DebugInfoContext) {
127 InlinedContext = DebugInfoContext->getInliningInfoForAddress(
128 ModuleOffset, getDILineInfoSpecifierFlags(Opts));
130 // Make sure there is at least one frame in context.
131 if (InlinedContext.getNumberOfFrames() == 0) {
132 InlinedContext.addFrame(DILineInfo());
134 // Override the function name in lower frame with name from symbol table.
135 if (Opts.PrintFunctions && Opts.UseSymbolTable) {
136 DIInliningInfo PatchedInlinedContext;
137 for (uint32_t i = 0, n = InlinedContext.getNumberOfFrames(); i < n; i++) {
138 DILineInfo LineInfo = InlinedContext.getFrame(i);
140 std::string FunctionName;
141 uint64_t Start, Size;
142 if (getNameFromSymbolTable(SymbolRef::ST_Function, ModuleOffset,
143 FunctionName, Start, Size)) {
144 patchFunctionNameInDILineInfo(FunctionName, LineInfo);
147 PatchedInlinedContext.addFrame(LineInfo);
149 InlinedContext = PatchedInlinedContext;
151 return InlinedContext;
154 bool ModuleInfo::symbolizeData(uint64_t ModuleOffset, std::string &Name,
155 uint64_t &Start, uint64_t &Size) const {
156 return getNameFromSymbolTable(SymbolRef::ST_Data, ModuleOffset, Name, Start,
160 const char LLVMSymbolizer::kBadString[] = "??";
162 std::string LLVMSymbolizer::symbolizeCode(const std::string &ModuleName,
163 uint64_t ModuleOffset) {
164 ModuleInfo *Info = getOrCreateModuleInfo(ModuleName);
166 return printDILineInfo(DILineInfo());
167 if (Opts.PrintInlining) {
168 DIInliningInfo InlinedContext =
169 Info->symbolizeInlinedCode(ModuleOffset, Opts);
170 uint32_t FramesNum = InlinedContext.getNumberOfFrames();
171 assert(FramesNum > 0);
173 for (uint32_t i = 0; i < FramesNum; i++) {
174 DILineInfo LineInfo = InlinedContext.getFrame(i);
175 Result += printDILineInfo(LineInfo);
179 DILineInfo LineInfo = Info->symbolizeCode(ModuleOffset, Opts);
180 return printDILineInfo(LineInfo);
183 std::string LLVMSymbolizer::symbolizeData(const std::string &ModuleName,
184 uint64_t ModuleOffset) {
185 std::string Name = kBadString;
188 if (Opts.UseSymbolTable) {
189 if (ModuleInfo *Info = getOrCreateModuleInfo(ModuleName)) {
190 if (Info->symbolizeData(ModuleOffset, Name, Start, Size))
194 std::stringstream ss;
195 ss << Name << "\n" << Start << " " << Size << "\n";
199 void LLVMSymbolizer::flush() {
200 DeleteContainerSeconds(Modules);
203 // Returns true if the object endianness is known.
204 static bool getObjectEndianness(const ObjectFile *Obj, bool &IsLittleEndian) {
205 // FIXME: Implement this when libLLVMObject allows to do it easily.
206 IsLittleEndian = true;
210 static ObjectFile *getObjectFile(const std::string &Path) {
211 OwningPtr<MemoryBuffer> Buff;
212 if (error(MemoryBuffer::getFile(Path, Buff)))
214 return ObjectFile::createObjectFile(Buff.take());
217 static std::string getDarwinDWARFResourceForModule(const std::string &Path) {
218 StringRef Basename = sys::path::filename(Path);
219 const std::string &DSymDirectory = Path + ".dSYM";
220 SmallString<16> ResourceName = StringRef(DSymDirectory);
221 sys::path::append(ResourceName, "Contents", "Resources", "DWARF");
222 sys::path::append(ResourceName, Basename);
223 return ResourceName.str();
227 LLVMSymbolizer::getOrCreateModuleInfo(const std::string &ModuleName) {
228 ModuleMapTy::iterator I = Modules.find(ModuleName);
229 if (I != Modules.end())
232 ObjectFile *Obj = getObjectFile(ModuleName);
234 // Module name doesn't point to a valid object file.
235 Modules.insert(make_pair(ModuleName, (ModuleInfo *)0));
239 DIContext *Context = 0;
241 if (getObjectEndianness(Obj, IsLittleEndian)) {
242 // On Darwin we may find DWARF in separate object file in
243 // resource directory.
244 ObjectFile *DbgObj = Obj;
245 if (isa<MachOObjectFile>(Obj)) {
246 const std::string &ResourceName =
247 getDarwinDWARFResourceForModule(ModuleName);
248 bool ResourceFileExists = false;
249 if (!sys::fs::exists(ResourceName, ResourceFileExists) &&
250 ResourceFileExists) {
251 if (ObjectFile *ResourceObj = getObjectFile(ResourceName))
252 DbgObj = ResourceObj;
255 Context = DIContext::getDWARFContext(DbgObj);
259 ModuleInfo *Info = new ModuleInfo(Obj, Context);
260 Modules.insert(make_pair(ModuleName, Info));
264 std::string LLVMSymbolizer::printDILineInfo(DILineInfo LineInfo) const {
265 // By default, DILineInfo contains "<invalid>" for function/filename it
266 // cannot fetch. We replace it to "??" to make our output closer to addr2line.
267 static const std::string kDILineInfoBadString = "<invalid>";
268 std::stringstream Result;
269 if (Opts.PrintFunctions) {
270 std::string FunctionName = LineInfo.getFunctionName();
271 if (FunctionName == kDILineInfoBadString)
272 FunctionName = kBadString;
273 DemangleName(FunctionName);
274 Result << FunctionName << "\n";
276 std::string Filename = LineInfo.getFileName();
277 if (Filename == kDILineInfoBadString)
278 Filename = kBadString;
279 Result << Filename << ":" << LineInfo.getLine() << ":" << LineInfo.getColumn()
284 #if !defined(_MSC_VER)
285 // Assume that __cxa_demangle is provided by libcxxabi (except for Windows).
286 extern "C" char *__cxa_demangle(const char *mangled_name, char *output_buffer,
287 size_t *length, int *status);
290 void LLVMSymbolizer::DemangleName(std::string &Name) const {
291 #if !defined(_MSC_VER)
295 char *DemangledName = __cxa_demangle(Name.c_str(), 0, 0, &status);
298 Name = DemangledName;
303 } // namespace symbolize