1 //===-- Symbol.cpp ----------------------------------------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 10 #include "lldb/Symbol/Symbol.h" 11 12 #include "lldb/Core/Module.h" 13 #include "lldb/Core/ModuleSpec.h" 14 #include "lldb/Core/Section.h" 15 #include "lldb/Core/Stream.h" 16 #include "lldb/Symbol/Function.h" 17 #include "lldb/Symbol/ObjectFile.h" 18 #include "lldb/Symbol/SymbolVendor.h" 19 #include "lldb/Symbol/Symtab.h" 20 #include "lldb/Target/Process.h" 21 #include "lldb/Target/Target.h" 22 23 using namespace lldb; 24 using namespace lldb_private; 25 26 Symbol::Symbol() 27 : SymbolContextScope(), m_uid(UINT32_MAX), m_type_data(0), 28 m_type_data_resolved(false), m_is_synthetic(false), m_is_debug(false), 29 m_is_external(false), m_size_is_sibling(false), 30 m_size_is_synthesized(false), m_size_is_valid(false), 31 m_demangled_is_synthesized(false), m_contains_linker_annotations(false), 32 m_type(eSymbolTypeInvalid), m_mangled(), m_addr_range(), m_flags() {} 33 34 Symbol::Symbol(uint32_t symID, const char *name, bool name_is_mangled, 35 SymbolType type, bool external, bool is_debug, 36 bool is_trampoline, bool is_artificial, 37 const lldb::SectionSP §ion_sp, addr_t offset, addr_t size, 38 bool size_is_valid, bool contains_linker_annotations, 39 uint32_t flags) 40 : SymbolContextScope(), m_uid(symID), m_type_data(0), 41 m_type_data_resolved(false), m_is_synthetic(is_artificial), 42 m_is_debug(is_debug), m_is_external(external), m_size_is_sibling(false), 43 m_size_is_synthesized(false), m_size_is_valid(size_is_valid || size > 0), 44 m_demangled_is_synthesized(false), 45 m_contains_linker_annotations(contains_linker_annotations), m_type(type), 46 m_mangled(ConstString(name), name_is_mangled), 47 m_addr_range(section_sp, offset, size), m_flags(flags) {} 48 49 Symbol::Symbol(uint32_t symID, const Mangled &mangled, SymbolType type, 50 bool external, bool is_debug, bool is_trampoline, 51 bool is_artificial, const AddressRange &range, 52 bool size_is_valid, bool contains_linker_annotations, 53 uint32_t flags) 54 : SymbolContextScope(), m_uid(symID), m_type_data(0), 55 m_type_data_resolved(false), m_is_synthetic(is_artificial), 56 m_is_debug(is_debug), m_is_external(external), m_size_is_sibling(false), 57 m_size_is_synthesized(false), 58 m_size_is_valid(size_is_valid || range.GetByteSize() > 0), 59 m_demangled_is_synthesized(false), 60 m_contains_linker_annotations(contains_linker_annotations), m_type(type), 61 m_mangled(mangled), m_addr_range(range), m_flags(flags) {} 62 63 Symbol::Symbol(const Symbol &rhs) 64 : SymbolContextScope(rhs), m_uid(rhs.m_uid), m_type_data(rhs.m_type_data), 65 m_type_data_resolved(rhs.m_type_data_resolved), 66 m_is_synthetic(rhs.m_is_synthetic), m_is_debug(rhs.m_is_debug), 67 m_is_external(rhs.m_is_external), 68 m_size_is_sibling(rhs.m_size_is_sibling), m_size_is_synthesized(false), 69 m_size_is_valid(rhs.m_size_is_valid), 70 m_demangled_is_synthesized(rhs.m_demangled_is_synthesized), 71 m_contains_linker_annotations(rhs.m_contains_linker_annotations), 72 m_type(rhs.m_type), m_mangled(rhs.m_mangled), 73 m_addr_range(rhs.m_addr_range), m_flags(rhs.m_flags) {} 74 75 const Symbol &Symbol::operator=(const Symbol &rhs) { 76 if (this != &rhs) { 77 SymbolContextScope::operator=(rhs); 78 m_uid = rhs.m_uid; 79 m_type_data = rhs.m_type_data; 80 m_type_data_resolved = rhs.m_type_data_resolved; 81 m_is_synthetic = rhs.m_is_synthetic; 82 m_is_debug = rhs.m_is_debug; 83 m_is_external = rhs.m_is_external; 84 m_size_is_sibling = rhs.m_size_is_sibling; 85 m_size_is_synthesized = rhs.m_size_is_sibling; 86 m_size_is_valid = rhs.m_size_is_valid; 87 m_demangled_is_synthesized = rhs.m_demangled_is_synthesized; 88 m_contains_linker_annotations = rhs.m_contains_linker_annotations; 89 m_type = rhs.m_type; 90 m_mangled = rhs.m_mangled; 91 m_addr_range = rhs.m_addr_range; 92 m_flags = rhs.m_flags; 93 } 94 return *this; 95 } 96 97 void Symbol::Clear() { 98 m_uid = UINT32_MAX; 99 m_mangled.Clear(); 100 m_type_data = 0; 101 m_type_data_resolved = false; 102 m_is_synthetic = false; 103 m_is_debug = false; 104 m_is_external = false; 105 m_size_is_sibling = false; 106 m_size_is_synthesized = false; 107 m_size_is_valid = false; 108 m_demangled_is_synthesized = false; 109 m_contains_linker_annotations = false; 110 m_type = eSymbolTypeInvalid; 111 m_flags = 0; 112 m_addr_range.Clear(); 113 } 114 115 bool Symbol::ValueIsAddress() const { 116 return m_addr_range.GetBaseAddress().GetSection().get() != nullptr; 117 } 118 119 ConstString Symbol::GetDisplayName() const { 120 if (!m_mangled) 121 return ConstString(); 122 return m_mangled.GetDisplayDemangledName(GetLanguage()); 123 } 124 125 ConstString Symbol::GetReExportedSymbolName() const { 126 if (m_type == eSymbolTypeReExported) { 127 // For eSymbolTypeReExported, the "const char *" from a ConstString 128 // is used as the offset in the address range base address. We can 129 // then make this back into a string that is the re-exported name. 130 intptr_t str_ptr = m_addr_range.GetBaseAddress().GetOffset(); 131 if (str_ptr != 0) 132 return ConstString((const char *)str_ptr); 133 else 134 return GetName(); 135 } 136 return ConstString(); 137 } 138 139 FileSpec Symbol::GetReExportedSymbolSharedLibrary() const { 140 if (m_type == eSymbolTypeReExported) { 141 // For eSymbolTypeReExported, the "const char *" from a ConstString 142 // is used as the offset in the address range base address. We can 143 // then make this back into a string that is the re-exported name. 144 intptr_t str_ptr = m_addr_range.GetByteSize(); 145 if (str_ptr != 0) 146 return FileSpec((const char *)str_ptr, false); 147 } 148 return FileSpec(); 149 } 150 151 void Symbol::SetReExportedSymbolName(const ConstString &name) { 152 SetType(eSymbolTypeReExported); 153 // For eSymbolTypeReExported, the "const char *" from a ConstString 154 // is used as the offset in the address range base address. 155 m_addr_range.GetBaseAddress().SetOffset((uintptr_t)name.GetCString()); 156 } 157 158 bool Symbol::SetReExportedSymbolSharedLibrary(const FileSpec &fspec) { 159 if (m_type == eSymbolTypeReExported) { 160 // For eSymbolTypeReExported, the "const char *" from a ConstString 161 // is used as the offset in the address range base address. 162 m_addr_range.SetByteSize( 163 (uintptr_t)ConstString(fspec.GetPath().c_str()).GetCString()); 164 return true; 165 } 166 return false; 167 } 168 169 uint32_t Symbol::GetSiblingIndex() const { 170 return m_size_is_sibling ? m_addr_range.GetByteSize() : UINT32_MAX; 171 } 172 173 bool Symbol::IsTrampoline() const { return m_type == eSymbolTypeTrampoline; } 174 175 bool Symbol::IsIndirect() const { return m_type == eSymbolTypeResolver; } 176 177 void Symbol::GetDescription(Stream *s, lldb::DescriptionLevel level, 178 Target *target) const { 179 s->Printf("id = {0x%8.8x}", m_uid); 180 181 if (m_addr_range.GetBaseAddress().GetSection()) { 182 if (ValueIsAddress()) { 183 const lldb::addr_t byte_size = GetByteSize(); 184 if (byte_size > 0) { 185 s->PutCString(", range = "); 186 m_addr_range.Dump(s, target, Address::DumpStyleLoadAddress, 187 Address::DumpStyleFileAddress); 188 } else { 189 s->PutCString(", address = "); 190 m_addr_range.GetBaseAddress().Dump(s, target, 191 Address::DumpStyleLoadAddress, 192 Address::DumpStyleFileAddress); 193 } 194 } else 195 s->Printf(", value = 0x%16.16" PRIx64, 196 m_addr_range.GetBaseAddress().GetOffset()); 197 } else { 198 if (m_size_is_sibling) 199 s->Printf(", sibling = %5" PRIu64, 200 m_addr_range.GetBaseAddress().GetOffset()); 201 else 202 s->Printf(", value = 0x%16.16" PRIx64, 203 m_addr_range.GetBaseAddress().GetOffset()); 204 } 205 ConstString demangled = m_mangled.GetDemangledName(GetLanguage()); 206 if (demangled) 207 s->Printf(", name=\"%s\"", demangled.AsCString()); 208 if (m_mangled.GetMangledName()) 209 s->Printf(", mangled=\"%s\"", m_mangled.GetMangledName().AsCString()); 210 } 211 212 void Symbol::Dump(Stream *s, Target *target, uint32_t index) const { 213 s->Printf("[%5u] %6u %c%c%c %-15s ", index, GetID(), m_is_debug ? 'D' : ' ', 214 m_is_synthetic ? 'S' : ' ', m_is_external ? 'X' : ' ', 215 GetTypeAsString()); 216 217 // Make sure the size of the symbol is up to date before dumping 218 GetByteSize(); 219 220 ConstString name = m_mangled.GetName(GetLanguage()); 221 if (ValueIsAddress()) { 222 if (!m_addr_range.GetBaseAddress().Dump(s, nullptr, 223 Address::DumpStyleFileAddress)) 224 s->Printf("%*s", 18, ""); 225 226 s->PutChar(' '); 227 228 if (!m_addr_range.GetBaseAddress().Dump(s, target, 229 Address::DumpStyleLoadAddress)) 230 s->Printf("%*s", 18, ""); 231 232 const char *format = m_size_is_sibling ? " Sibling -> [%5llu] 0x%8.8x %s\n" 233 : " 0x%16.16" PRIx64 " 0x%8.8x %s\n"; 234 s->Printf(format, GetByteSize(), m_flags, name.AsCString("")); 235 } else if (m_type == eSymbolTypeReExported) { 236 s->Printf( 237 " 0x%8.8x %s", 238 m_flags, name.AsCString("")); 239 240 ConstString reexport_name = GetReExportedSymbolName(); 241 intptr_t shlib = m_addr_range.GetByteSize(); 242 if (shlib) 243 s->Printf(" -> %s`%s\n", (const char *)shlib, reexport_name.GetCString()); 244 else 245 s->Printf(" -> %s\n", reexport_name.GetCString()); 246 } else { 247 const char *format = 248 m_size_is_sibling 249 ? "0x%16.16" PRIx64 250 " Sibling -> [%5llu] 0x%8.8x %s\n" 251 : "0x%16.16" PRIx64 " 0x%16.16" PRIx64 252 " 0x%8.8x %s\n"; 253 s->Printf(format, m_addr_range.GetBaseAddress().GetOffset(), GetByteSize(), 254 m_flags, name.AsCString("")); 255 } 256 } 257 258 uint32_t Symbol::GetPrologueByteSize() { 259 if (m_type == eSymbolTypeCode || m_type == eSymbolTypeResolver) { 260 if (!m_type_data_resolved) { 261 m_type_data_resolved = true; 262 263 const Address &base_address = m_addr_range.GetBaseAddress(); 264 Function *function = base_address.CalculateSymbolContextFunction(); 265 if (function) { 266 // Functions have line entries which can also potentially have end of 267 // prologue information. 268 // So if this symbol points to a function, use the prologue information 269 // from there. 270 m_type_data = function->GetPrologueByteSize(); 271 } else { 272 ModuleSP module_sp(base_address.GetModule()); 273 SymbolContext sc; 274 if (module_sp) { 275 uint32_t resolved_flags = module_sp->ResolveSymbolContextForAddress( 276 base_address, eSymbolContextLineEntry, sc); 277 if (resolved_flags & eSymbolContextLineEntry) { 278 // Default to the end of the first line entry. 279 m_type_data = sc.line_entry.range.GetByteSize(); 280 281 // Set address for next line. 282 Address addr(base_address); 283 addr.Slide(m_type_data); 284 285 // Check the first few instructions and look for one that has a line 286 // number that is 287 // different than the first entry. This is also done in 288 // Function::GetPrologueByteSize(). 289 uint16_t total_offset = m_type_data; 290 for (int idx = 0; idx < 6; ++idx) { 291 SymbolContext sc_temp; 292 resolved_flags = module_sp->ResolveSymbolContextForAddress( 293 addr, eSymbolContextLineEntry, sc_temp); 294 // Make sure we got line number information... 295 if (!(resolved_flags & eSymbolContextLineEntry)) 296 break; 297 298 // If this line number is different than our first one, use it and 299 // we're done. 300 if (sc_temp.line_entry.line != sc.line_entry.line) { 301 m_type_data = total_offset; 302 break; 303 } 304 305 // Slide addr up to the next line address. 306 addr.Slide(sc_temp.line_entry.range.GetByteSize()); 307 total_offset += sc_temp.line_entry.range.GetByteSize(); 308 // If we've gone too far, bail out. 309 if (total_offset >= m_addr_range.GetByteSize()) 310 break; 311 } 312 313 // Sanity check - this may be a function in the middle of code that 314 // has debug information, but 315 // not for this symbol. So the line entries surrounding us won't 316 // lie inside our function. 317 // In that case, the line entry will be bigger than we are, so we do 318 // that quick check and 319 // if that is true, we just return 0. 320 if (m_type_data >= m_addr_range.GetByteSize()) 321 m_type_data = 0; 322 } else { 323 // TODO: expose something in Process to figure out the 324 // size of a function prologue. 325 m_type_data = 0; 326 } 327 } 328 } 329 } 330 return m_type_data; 331 } 332 return 0; 333 } 334 335 bool Symbol::Compare(const ConstString &name, SymbolType type) const { 336 if (type == eSymbolTypeAny || m_type == type) 337 return m_mangled.GetMangledName() == name || 338 m_mangled.GetDemangledName(GetLanguage()) == name; 339 return false; 340 } 341 342 #define ENUM_TO_CSTRING(x) \ 343 case eSymbolType##x: \ 344 return #x; 345 346 const char *Symbol::GetTypeAsString() const { 347 switch (m_type) { 348 ENUM_TO_CSTRING(Invalid); 349 ENUM_TO_CSTRING(Absolute); 350 ENUM_TO_CSTRING(Code); 351 ENUM_TO_CSTRING(Resolver); 352 ENUM_TO_CSTRING(Data); 353 ENUM_TO_CSTRING(Trampoline); 354 ENUM_TO_CSTRING(Runtime); 355 ENUM_TO_CSTRING(Exception); 356 ENUM_TO_CSTRING(SourceFile); 357 ENUM_TO_CSTRING(HeaderFile); 358 ENUM_TO_CSTRING(ObjectFile); 359 ENUM_TO_CSTRING(CommonBlock); 360 ENUM_TO_CSTRING(Block); 361 ENUM_TO_CSTRING(Local); 362 ENUM_TO_CSTRING(Param); 363 ENUM_TO_CSTRING(Variable); 364 ENUM_TO_CSTRING(VariableType); 365 ENUM_TO_CSTRING(LineEntry); 366 ENUM_TO_CSTRING(LineHeader); 367 ENUM_TO_CSTRING(ScopeBegin); 368 ENUM_TO_CSTRING(ScopeEnd); 369 ENUM_TO_CSTRING(Additional); 370 ENUM_TO_CSTRING(Compiler); 371 ENUM_TO_CSTRING(Instrumentation); 372 ENUM_TO_CSTRING(Undefined); 373 ENUM_TO_CSTRING(ObjCClass); 374 ENUM_TO_CSTRING(ObjCMetaClass); 375 ENUM_TO_CSTRING(ObjCIVar); 376 ENUM_TO_CSTRING(ReExported); 377 default: 378 break; 379 } 380 return "<unknown SymbolType>"; 381 } 382 383 void Symbol::CalculateSymbolContext(SymbolContext *sc) { 384 // Symbols can reconstruct the symbol and the module in the symbol context 385 sc->symbol = this; 386 if (ValueIsAddress()) 387 sc->module_sp = GetAddressRef().GetModule(); 388 else 389 sc->module_sp.reset(); 390 } 391 392 ModuleSP Symbol::CalculateSymbolContextModule() { 393 if (ValueIsAddress()) 394 return GetAddressRef().GetModule(); 395 return ModuleSP(); 396 } 397 398 Symbol *Symbol::CalculateSymbolContextSymbol() { return this; } 399 400 void Symbol::DumpSymbolContext(Stream *s) { 401 bool dumped_module = false; 402 if (ValueIsAddress()) { 403 ModuleSP module_sp(GetAddressRef().GetModule()); 404 if (module_sp) { 405 dumped_module = true; 406 module_sp->DumpSymbolContext(s); 407 } 408 } 409 if (dumped_module) 410 s->PutCString(", "); 411 412 s->Printf("Symbol{0x%8.8x}", GetID()); 413 } 414 415 lldb::addr_t Symbol::GetByteSize() const { return m_addr_range.GetByteSize(); } 416 417 Symbol *Symbol::ResolveReExportedSymbolInModuleSpec( 418 Target &target, ConstString &reexport_name, ModuleSpec &module_spec, 419 ModuleList &seen_modules) const { 420 ModuleSP module_sp; 421 if (module_spec.GetFileSpec()) { 422 // Try searching for the module file spec first using the full path 423 module_sp = target.GetImages().FindFirstModule(module_spec); 424 if (!module_sp) { 425 // Next try and find the module by basename in case environment 426 // variables or other runtime trickery causes shared libraries 427 // to be loaded from alternate paths 428 module_spec.GetFileSpec().GetDirectory().Clear(); 429 module_sp = target.GetImages().FindFirstModule(module_spec); 430 } 431 } 432 433 if (module_sp) { 434 // There should not be cycles in the reexport list, but we don't want to 435 // crash if there are so make sure 436 // we haven't seen this before: 437 if (!seen_modules.AppendIfNeeded(module_sp)) 438 return nullptr; 439 440 lldb_private::SymbolContextList sc_list; 441 module_sp->FindSymbolsWithNameAndType(reexport_name, eSymbolTypeAny, 442 sc_list); 443 const size_t num_scs = sc_list.GetSize(); 444 if (num_scs > 0) { 445 for (size_t i = 0; i < num_scs; ++i) { 446 lldb_private::SymbolContext sc; 447 if (sc_list.GetContextAtIndex(i, sc)) { 448 if (sc.symbol->IsExternal()) 449 return sc.symbol; 450 } 451 } 452 } 453 // If we didn't find the symbol in this module, it may be because this 454 // module re-exports some 455 // whole other library. We have to search those as well: 456 seen_modules.Append(module_sp); 457 458 FileSpecList reexported_libraries = 459 module_sp->GetObjectFile()->GetReExportedLibraries(); 460 size_t num_reexported_libraries = reexported_libraries.GetSize(); 461 for (size_t idx = 0; idx < num_reexported_libraries; idx++) { 462 ModuleSpec reexported_module_spec; 463 reexported_module_spec.GetFileSpec() = 464 reexported_libraries.GetFileSpecAtIndex(idx); 465 Symbol *result_symbol = ResolveReExportedSymbolInModuleSpec( 466 target, reexport_name, reexported_module_spec, seen_modules); 467 if (result_symbol) 468 return result_symbol; 469 } 470 } 471 return nullptr; 472 } 473 474 Symbol *Symbol::ResolveReExportedSymbol(Target &target) const { 475 ConstString reexport_name(GetReExportedSymbolName()); 476 if (reexport_name) { 477 ModuleSpec module_spec; 478 ModuleList seen_modules; 479 module_spec.GetFileSpec() = GetReExportedSymbolSharedLibrary(); 480 if (module_spec.GetFileSpec()) { 481 return ResolveReExportedSymbolInModuleSpec(target, reexport_name, 482 module_spec, seen_modules); 483 } 484 } 485 return nullptr; 486 } 487 488 lldb::addr_t Symbol::GetFileAddress() const { 489 if (ValueIsAddress()) 490 return GetAddressRef().GetFileAddress(); 491 else 492 return LLDB_INVALID_ADDRESS; 493 } 494 495 lldb::addr_t Symbol::GetLoadAddress(Target *target) const { 496 if (ValueIsAddress()) 497 return GetAddressRef().GetLoadAddress(target); 498 else 499 return LLDB_INVALID_ADDRESS; 500 } 501 502 ConstString Symbol::GetName() const { return m_mangled.GetName(GetLanguage()); } 503 504 ConstString Symbol::GetNameNoArguments() const { 505 return m_mangled.GetName(GetLanguage(), 506 Mangled::ePreferDemangledWithoutArguments); 507 } 508 509 lldb::addr_t Symbol::ResolveCallableAddress(Target &target) const { 510 if (GetType() == lldb::eSymbolTypeUndefined) 511 return LLDB_INVALID_ADDRESS; 512 513 Address func_so_addr; 514 515 bool is_indirect = IsIndirect(); 516 if (GetType() == eSymbolTypeReExported) { 517 Symbol *reexported_symbol = ResolveReExportedSymbol(target); 518 if (reexported_symbol) { 519 func_so_addr = reexported_symbol->GetAddress(); 520 is_indirect = reexported_symbol->IsIndirect(); 521 } 522 } else { 523 func_so_addr = GetAddress(); 524 is_indirect = IsIndirect(); 525 } 526 527 if (func_so_addr.IsValid()) { 528 if (!target.GetProcessSP() && is_indirect) { 529 // can't resolve indirect symbols without calling a function... 530 return LLDB_INVALID_ADDRESS; 531 } 532 533 lldb::addr_t load_addr = 534 func_so_addr.GetCallableLoadAddress(&target, is_indirect); 535 536 if (load_addr != LLDB_INVALID_ADDRESS) { 537 return load_addr; 538 } 539 } 540 541 return LLDB_INVALID_ADDRESS; 542 } 543 544 lldb::DisassemblerSP Symbol::GetInstructions(const ExecutionContext &exe_ctx, 545 const char *flavor, 546 bool prefer_file_cache) { 547 ModuleSP module_sp(m_addr_range.GetBaseAddress().GetModule()); 548 if (module_sp) { 549 const bool prefer_file_cache = false; 550 return Disassembler::DisassembleRange(module_sp->GetArchitecture(), nullptr, 551 flavor, exe_ctx, m_addr_range, 552 prefer_file_cache); 553 } 554 return lldb::DisassemblerSP(); 555 } 556 557 bool Symbol::GetDisassembly(const ExecutionContext &exe_ctx, const char *flavor, 558 bool prefer_file_cache, Stream &strm) { 559 lldb::DisassemblerSP disassembler_sp = 560 GetInstructions(exe_ctx, flavor, prefer_file_cache); 561 if (disassembler_sp) { 562 const bool show_address = true; 563 const bool show_bytes = false; 564 disassembler_sp->GetInstructionList().Dump(&strm, show_address, show_bytes, 565 &exe_ctx); 566 return true; 567 } 568 return false; 569 } 570 571 bool Symbol::ContainsFileAddress(lldb::addr_t file_addr) const { 572 return m_addr_range.ContainsFileAddress(file_addr); 573 } 574