//===-- Symbol.cpp --------------------------------------------------------===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// #include "lldb/Symbol/Symbol.h" #include "lldb/Core/Module.h" #include "lldb/Core/ModuleSpec.h" #include "lldb/Core/Section.h" #include "lldb/Symbol/Function.h" #include "lldb/Symbol/ObjectFile.h" #include "lldb/Symbol/SymbolVendor.h" #include "lldb/Symbol/Symtab.h" #include "lldb/Target/Process.h" #include "lldb/Target/Target.h" #include "lldb/Utility/Stream.h" using namespace lldb; using namespace lldb_private; Symbol::Symbol() : SymbolContextScope(), m_uid(UINT32_MAX), m_type_data(0), m_type_data_resolved(false), m_is_synthetic(false), m_is_debug(false), m_is_external(false), m_size_is_sibling(false), m_size_is_synthesized(false), m_size_is_valid(false), m_demangled_is_synthesized(false), m_contains_linker_annotations(false), m_is_weak(false), m_type(eSymbolTypeInvalid), m_mangled(), m_addr_range(), m_flags() {} Symbol::Symbol(uint32_t symID, llvm::StringRef name, SymbolType type, bool external, bool is_debug, bool is_trampoline, bool is_artificial, const lldb::SectionSP §ion_sp, addr_t offset, addr_t size, bool size_is_valid, bool contains_linker_annotations, uint32_t flags) : SymbolContextScope(), m_uid(symID), m_type_data(0), m_type_data_resolved(false), m_is_synthetic(is_artificial), m_is_debug(is_debug), m_is_external(external), m_size_is_sibling(false), m_size_is_synthesized(false), m_size_is_valid(size_is_valid || size > 0), m_demangled_is_synthesized(false), m_contains_linker_annotations(contains_linker_annotations), m_is_weak(false), m_type(type), m_mangled(name), m_addr_range(section_sp, offset, size), m_flags(flags) {} Symbol::Symbol(uint32_t symID, const Mangled &mangled, SymbolType type, bool external, bool is_debug, bool is_trampoline, bool is_artificial, const AddressRange &range, bool size_is_valid, bool contains_linker_annotations, uint32_t flags) : SymbolContextScope(), m_uid(symID), m_type_data(0), m_type_data_resolved(false), m_is_synthetic(is_artificial), m_is_debug(is_debug), m_is_external(external), m_size_is_sibling(false), m_size_is_synthesized(false), m_size_is_valid(size_is_valid || range.GetByteSize() > 0), m_demangled_is_synthesized(false), m_contains_linker_annotations(contains_linker_annotations), m_is_weak(false), m_type(type), m_mangled(mangled), m_addr_range(range), m_flags(flags) {} Symbol::Symbol(const Symbol &rhs) : SymbolContextScope(rhs), m_uid(rhs.m_uid), m_type_data(rhs.m_type_data), m_type_data_resolved(rhs.m_type_data_resolved), m_is_synthetic(rhs.m_is_synthetic), m_is_debug(rhs.m_is_debug), m_is_external(rhs.m_is_external), m_size_is_sibling(rhs.m_size_is_sibling), m_size_is_synthesized(false), m_size_is_valid(rhs.m_size_is_valid), m_demangled_is_synthesized(rhs.m_demangled_is_synthesized), m_contains_linker_annotations(rhs.m_contains_linker_annotations), m_is_weak(rhs.m_is_weak), m_type(rhs.m_type), m_mangled(rhs.m_mangled), m_addr_range(rhs.m_addr_range), m_flags(rhs.m_flags) {} const Symbol &Symbol::operator=(const Symbol &rhs) { if (this != &rhs) { SymbolContextScope::operator=(rhs); m_uid = rhs.m_uid; m_type_data = rhs.m_type_data; m_type_data_resolved = rhs.m_type_data_resolved; m_is_synthetic = rhs.m_is_synthetic; m_is_debug = rhs.m_is_debug; m_is_external = rhs.m_is_external; m_size_is_sibling = rhs.m_size_is_sibling; m_size_is_synthesized = rhs.m_size_is_sibling; m_size_is_valid = rhs.m_size_is_valid; m_demangled_is_synthesized = rhs.m_demangled_is_synthesized; m_contains_linker_annotations = rhs.m_contains_linker_annotations; m_is_weak = rhs.m_is_weak; m_type = rhs.m_type; m_mangled = rhs.m_mangled; m_addr_range = rhs.m_addr_range; m_flags = rhs.m_flags; } return *this; } void Symbol::Clear() { m_uid = UINT32_MAX; m_mangled.Clear(); m_type_data = 0; m_type_data_resolved = false; m_is_synthetic = false; m_is_debug = false; m_is_external = false; m_size_is_sibling = false; m_size_is_synthesized = false; m_size_is_valid = false; m_demangled_is_synthesized = false; m_contains_linker_annotations = false; m_is_weak = false; m_type = eSymbolTypeInvalid; m_flags = 0; m_addr_range.Clear(); } bool Symbol::ValueIsAddress() const { return m_addr_range.GetBaseAddress().GetSection().get() != nullptr; } ConstString Symbol::GetDisplayName() const { return m_mangled.GetDisplayDemangledName(); } ConstString Symbol::GetReExportedSymbolName() const { if (m_type == eSymbolTypeReExported) { // For eSymbolTypeReExported, the "const char *" from a ConstString is used // as the offset in the address range base address. We can then make this // back into a string that is the re-exported name. intptr_t str_ptr = m_addr_range.GetBaseAddress().GetOffset(); if (str_ptr != 0) return ConstString((const char *)str_ptr); else return GetName(); } return ConstString(); } FileSpec Symbol::GetReExportedSymbolSharedLibrary() const { if (m_type == eSymbolTypeReExported) { // For eSymbolTypeReExported, the "const char *" from a ConstString is used // as the offset in the address range base address. We can then make this // back into a string that is the re-exported name. intptr_t str_ptr = m_addr_range.GetByteSize(); if (str_ptr != 0) return FileSpec((const char *)str_ptr); } return FileSpec(); } void Symbol::SetReExportedSymbolName(ConstString name) { SetType(eSymbolTypeReExported); // For eSymbolTypeReExported, the "const char *" from a ConstString is used // as the offset in the address range base address. m_addr_range.GetBaseAddress().SetOffset((uintptr_t)name.GetCString()); } bool Symbol::SetReExportedSymbolSharedLibrary(const FileSpec &fspec) { if (m_type == eSymbolTypeReExported) { // For eSymbolTypeReExported, the "const char *" from a ConstString is used // as the offset in the address range base address. m_addr_range.SetByteSize( (uintptr_t)ConstString(fspec.GetPath().c_str()).GetCString()); return true; } return false; } uint32_t Symbol::GetSiblingIndex() const { return m_size_is_sibling ? m_addr_range.GetByteSize() : UINT32_MAX; } bool Symbol::IsTrampoline() const { return m_type == eSymbolTypeTrampoline; } bool Symbol::IsIndirect() const { return m_type == eSymbolTypeResolver; } void Symbol::GetDescription(Stream *s, lldb::DescriptionLevel level, Target *target) const { s->Printf("id = {0x%8.8x}", m_uid); if (m_addr_range.GetBaseAddress().GetSection()) { if (ValueIsAddress()) { const lldb::addr_t byte_size = GetByteSize(); if (byte_size > 0) { s->PutCString(", range = "); m_addr_range.Dump(s, target, Address::DumpStyleLoadAddress, Address::DumpStyleFileAddress); } else { s->PutCString(", address = "); m_addr_range.GetBaseAddress().Dump(s, target, Address::DumpStyleLoadAddress, Address::DumpStyleFileAddress); } } else s->Printf(", value = 0x%16.16" PRIx64, m_addr_range.GetBaseAddress().GetOffset()); } else { if (m_size_is_sibling) s->Printf(", sibling = %5" PRIu64, m_addr_range.GetBaseAddress().GetOffset()); else s->Printf(", value = 0x%16.16" PRIx64, m_addr_range.GetBaseAddress().GetOffset()); } ConstString demangled = m_mangled.GetDemangledName(); if (demangled) s->Printf(", name=\"%s\"", demangled.AsCString()); if (m_mangled.GetMangledName()) s->Printf(", mangled=\"%s\"", m_mangled.GetMangledName().AsCString()); } void Symbol::Dump(Stream *s, Target *target, uint32_t index, Mangled::NamePreference name_preference) const { s->Printf("[%5u] %6u %c%c%c %-15s ", index, GetID(), m_is_debug ? 'D' : ' ', m_is_synthetic ? 'S' : ' ', m_is_external ? 'X' : ' ', GetTypeAsString()); // Make sure the size of the symbol is up to date before dumping GetByteSize(); ConstString name = m_mangled.GetName(name_preference); if (ValueIsAddress()) { if (!m_addr_range.GetBaseAddress().Dump(s, nullptr, Address::DumpStyleFileAddress)) s->Printf("%*s", 18, ""); s->PutChar(' '); if (!m_addr_range.GetBaseAddress().Dump(s, target, Address::DumpStyleLoadAddress)) s->Printf("%*s", 18, ""); const char *format = m_size_is_sibling ? " Sibling -> [%5llu] 0x%8.8x %s\n" : " 0x%16.16" PRIx64 " 0x%8.8x %s\n"; s->Printf(format, GetByteSize(), m_flags, name.AsCString("")); } else if (m_type == eSymbolTypeReExported) { s->Printf( " 0x%8.8x %s", m_flags, name.AsCString("")); ConstString reexport_name = GetReExportedSymbolName(); intptr_t shlib = m_addr_range.GetByteSize(); if (shlib) s->Printf(" -> %s`%s\n", (const char *)shlib, reexport_name.GetCString()); else s->Printf(" -> %s\n", reexport_name.GetCString()); } else { const char *format = m_size_is_sibling ? "0x%16.16" PRIx64 " Sibling -> [%5llu] 0x%8.8x %s\n" : "0x%16.16" PRIx64 " 0x%16.16" PRIx64 " 0x%8.8x %s\n"; s->Printf(format, m_addr_range.GetBaseAddress().GetOffset(), GetByteSize(), m_flags, name.AsCString("")); } } uint32_t Symbol::GetPrologueByteSize() { if (m_type == eSymbolTypeCode || m_type == eSymbolTypeResolver) { if (!m_type_data_resolved) { m_type_data_resolved = true; const Address &base_address = m_addr_range.GetBaseAddress(); Function *function = base_address.CalculateSymbolContextFunction(); if (function) { // Functions have line entries which can also potentially have end of // prologue information. So if this symbol points to a function, use // the prologue information from there. m_type_data = function->GetPrologueByteSize(); } else { ModuleSP module_sp(base_address.GetModule()); SymbolContext sc; if (module_sp) { uint32_t resolved_flags = module_sp->ResolveSymbolContextForAddress( base_address, eSymbolContextLineEntry, sc); if (resolved_flags & eSymbolContextLineEntry) { // Default to the end of the first line entry. m_type_data = sc.line_entry.range.GetByteSize(); // Set address for next line. Address addr(base_address); addr.Slide(m_type_data); // Check the first few instructions and look for one that has a // line number that is different than the first entry. This is also // done in Function::GetPrologueByteSize(). uint16_t total_offset = m_type_data; for (int idx = 0; idx < 6; ++idx) { SymbolContext sc_temp; resolved_flags = module_sp->ResolveSymbolContextForAddress( addr, eSymbolContextLineEntry, sc_temp); // Make sure we got line number information... if (!(resolved_flags & eSymbolContextLineEntry)) break; // If this line number is different than our first one, use it // and we're done. if (sc_temp.line_entry.line != sc.line_entry.line) { m_type_data = total_offset; break; } // Slide addr up to the next line address. addr.Slide(sc_temp.line_entry.range.GetByteSize()); total_offset += sc_temp.line_entry.range.GetByteSize(); // If we've gone too far, bail out. if (total_offset >= m_addr_range.GetByteSize()) break; } // Sanity check - this may be a function in the middle of code that // has debug information, but not for this symbol. So the line // entries surrounding us won't lie inside our function. In that // case, the line entry will be bigger than we are, so we do that // quick check and if that is true, we just return 0. if (m_type_data >= m_addr_range.GetByteSize()) m_type_data = 0; } else { // TODO: expose something in Process to figure out the // size of a function prologue. m_type_data = 0; } } } } return m_type_data; } return 0; } bool Symbol::Compare(ConstString name, SymbolType type) const { if (type == eSymbolTypeAny || m_type == type) return m_mangled.GetMangledName() == name || m_mangled.GetDemangledName() == name; return false; } #define ENUM_TO_CSTRING(x) \ case eSymbolType##x: \ return #x; const char *Symbol::GetTypeAsString() const { switch (m_type) { ENUM_TO_CSTRING(Invalid); ENUM_TO_CSTRING(Absolute); ENUM_TO_CSTRING(Code); ENUM_TO_CSTRING(Resolver); ENUM_TO_CSTRING(Data); ENUM_TO_CSTRING(Trampoline); ENUM_TO_CSTRING(Runtime); ENUM_TO_CSTRING(Exception); ENUM_TO_CSTRING(SourceFile); ENUM_TO_CSTRING(HeaderFile); ENUM_TO_CSTRING(ObjectFile); ENUM_TO_CSTRING(CommonBlock); ENUM_TO_CSTRING(Block); ENUM_TO_CSTRING(Local); ENUM_TO_CSTRING(Param); ENUM_TO_CSTRING(Variable); ENUM_TO_CSTRING(VariableType); ENUM_TO_CSTRING(LineEntry); ENUM_TO_CSTRING(LineHeader); ENUM_TO_CSTRING(ScopeBegin); ENUM_TO_CSTRING(ScopeEnd); ENUM_TO_CSTRING(Additional); ENUM_TO_CSTRING(Compiler); ENUM_TO_CSTRING(Instrumentation); ENUM_TO_CSTRING(Undefined); ENUM_TO_CSTRING(ObjCClass); ENUM_TO_CSTRING(ObjCMetaClass); ENUM_TO_CSTRING(ObjCIVar); ENUM_TO_CSTRING(ReExported); default: break; } return ""; } void Symbol::CalculateSymbolContext(SymbolContext *sc) { // Symbols can reconstruct the symbol and the module in the symbol context sc->symbol = this; if (ValueIsAddress()) sc->module_sp = GetAddressRef().GetModule(); else sc->module_sp.reset(); } ModuleSP Symbol::CalculateSymbolContextModule() { if (ValueIsAddress()) return GetAddressRef().GetModule(); return ModuleSP(); } Symbol *Symbol::CalculateSymbolContextSymbol() { return this; } void Symbol::DumpSymbolContext(Stream *s) { bool dumped_module = false; if (ValueIsAddress()) { ModuleSP module_sp(GetAddressRef().GetModule()); if (module_sp) { dumped_module = true; module_sp->DumpSymbolContext(s); } } if (dumped_module) s->PutCString(", "); s->Printf("Symbol{0x%8.8x}", GetID()); } lldb::addr_t Symbol::GetByteSize() const { return m_addr_range.GetByteSize(); } Symbol *Symbol::ResolveReExportedSymbolInModuleSpec( Target &target, ConstString &reexport_name, ModuleSpec &module_spec, ModuleList &seen_modules) const { ModuleSP module_sp; if (module_spec.GetFileSpec()) { // Try searching for the module file spec first using the full path module_sp = target.GetImages().FindFirstModule(module_spec); if (!module_sp) { // Next try and find the module by basename in case environment variables // or other runtime trickery causes shared libraries to be loaded from // alternate paths module_spec.GetFileSpec().GetDirectory().Clear(); module_sp = target.GetImages().FindFirstModule(module_spec); } } if (module_sp) { // There should not be cycles in the reexport list, but we don't want to // crash if there are so make sure we haven't seen this before: if (!seen_modules.AppendIfNeeded(module_sp)) return nullptr; lldb_private::SymbolContextList sc_list; module_sp->FindSymbolsWithNameAndType(reexport_name, eSymbolTypeAny, sc_list); const size_t num_scs = sc_list.GetSize(); if (num_scs > 0) { for (size_t i = 0; i < num_scs; ++i) { lldb_private::SymbolContext sc; if (sc_list.GetContextAtIndex(i, sc)) { if (sc.symbol->IsExternal()) return sc.symbol; } } } // If we didn't find the symbol in this module, it may be because this // module re-exports some whole other library. We have to search those as // well: seen_modules.Append(module_sp); FileSpecList reexported_libraries = module_sp->GetObjectFile()->GetReExportedLibraries(); size_t num_reexported_libraries = reexported_libraries.GetSize(); for (size_t idx = 0; idx < num_reexported_libraries; idx++) { ModuleSpec reexported_module_spec; reexported_module_spec.GetFileSpec() = reexported_libraries.GetFileSpecAtIndex(idx); Symbol *result_symbol = ResolveReExportedSymbolInModuleSpec( target, reexport_name, reexported_module_spec, seen_modules); if (result_symbol) return result_symbol; } } return nullptr; } Symbol *Symbol::ResolveReExportedSymbol(Target &target) const { ConstString reexport_name(GetReExportedSymbolName()); if (reexport_name) { ModuleSpec module_spec; ModuleList seen_modules; module_spec.GetFileSpec() = GetReExportedSymbolSharedLibrary(); if (module_spec.GetFileSpec()) { return ResolveReExportedSymbolInModuleSpec(target, reexport_name, module_spec, seen_modules); } } return nullptr; } lldb::addr_t Symbol::GetFileAddress() const { if (ValueIsAddress()) return GetAddressRef().GetFileAddress(); else return LLDB_INVALID_ADDRESS; } lldb::addr_t Symbol::GetLoadAddress(Target *target) const { if (ValueIsAddress()) return GetAddressRef().GetLoadAddress(target); else return LLDB_INVALID_ADDRESS; } ConstString Symbol::GetName() const { return m_mangled.GetName(); } ConstString Symbol::GetNameNoArguments() const { return m_mangled.GetName(Mangled::ePreferDemangledWithoutArguments); } lldb::addr_t Symbol::ResolveCallableAddress(Target &target) const { if (GetType() == lldb::eSymbolTypeUndefined) return LLDB_INVALID_ADDRESS; Address func_so_addr; bool is_indirect = IsIndirect(); if (GetType() == eSymbolTypeReExported) { Symbol *reexported_symbol = ResolveReExportedSymbol(target); if (reexported_symbol) { func_so_addr = reexported_symbol->GetAddress(); is_indirect = reexported_symbol->IsIndirect(); } } else { func_so_addr = GetAddress(); is_indirect = IsIndirect(); } if (func_so_addr.IsValid()) { if (!target.GetProcessSP() && is_indirect) { // can't resolve indirect symbols without calling a function... return LLDB_INVALID_ADDRESS; } lldb::addr_t load_addr = func_so_addr.GetCallableLoadAddress(&target, is_indirect); if (load_addr != LLDB_INVALID_ADDRESS) { return load_addr; } } return LLDB_INVALID_ADDRESS; } lldb::DisassemblerSP Symbol::GetInstructions(const ExecutionContext &exe_ctx, const char *flavor, bool prefer_file_cache) { ModuleSP module_sp(m_addr_range.GetBaseAddress().GetModule()); if (module_sp && exe_ctx.HasTargetScope()) { const bool prefer_file_cache = false; return Disassembler::DisassembleRange(module_sp->GetArchitecture(), nullptr, flavor, exe_ctx.GetTargetRef(), m_addr_range, prefer_file_cache); } return lldb::DisassemblerSP(); } bool Symbol::GetDisassembly(const ExecutionContext &exe_ctx, const char *flavor, bool prefer_file_cache, Stream &strm) { lldb::DisassemblerSP disassembler_sp = GetInstructions(exe_ctx, flavor, prefer_file_cache); if (disassembler_sp) { const bool show_address = true; const bool show_bytes = false; disassembler_sp->GetInstructionList().Dump(&strm, show_address, show_bytes, &exe_ctx); return true; } return false; } bool Symbol::ContainsFileAddress(lldb::addr_t file_addr) const { return m_addr_range.ContainsFileAddress(file_addr); }