1 //===-- SymbolFile.h --------------------------------------------*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #ifndef LLDB_SYMBOL_SYMBOLFILE_H 10 #define LLDB_SYMBOL_SYMBOLFILE_H 11 12 #include "lldb/Core/PluginInterface.h" 13 #include "lldb/Core/SourceLocationSpec.h" 14 #include "lldb/Symbol/CompilerDecl.h" 15 #include "lldb/Symbol/CompilerDeclContext.h" 16 #include "lldb/Symbol/CompilerType.h" 17 #include "lldb/Symbol/Function.h" 18 #include "lldb/Symbol/SourceModule.h" 19 #include "lldb/Symbol/Type.h" 20 #include "lldb/Symbol/TypeList.h" 21 #include "lldb/Symbol/TypeSystem.h" 22 #include "lldb/Target/Statistics.h" 23 #include "lldb/Utility/XcodeSDK.h" 24 #include "lldb/lldb-private.h" 25 #include "llvm/ADT/DenseSet.h" 26 #include "llvm/Support/Errc.h" 27 28 #include <mutex> 29 30 #if defined(LLDB_CONFIGURATION_DEBUG) 31 #define ASSERT_MODULE_LOCK(expr) (expr->AssertModuleLock()) 32 #else 33 #define ASSERT_MODULE_LOCK(expr) ((void)0) 34 #endif 35 36 namespace lldb_private { 37 38 class SymbolFile : public PluginInterface { 39 /// LLVM RTTI support. 40 static char ID; 41 42 public: 43 /// LLVM RTTI support. 44 /// \{ 45 virtual bool isA(const void *ClassID) const { return ClassID == &ID; } 46 static bool classof(const SymbolFile *obj) { return obj->isA(&ID); } 47 /// \} 48 49 // Symbol file ability bits. 50 // 51 // Each symbol file can claim to support one or more symbol file abilities. 52 // These get returned from SymbolFile::GetAbilities(). These help us to 53 // determine which plug-in will be best to load the debug information found 54 // in files. 55 enum Abilities { 56 CompileUnits = (1u << 0), 57 LineTables = (1u << 1), 58 Functions = (1u << 2), 59 Blocks = (1u << 3), 60 GlobalVariables = (1u << 4), 61 LocalVariables = (1u << 5), 62 VariableTypes = (1u << 6), 63 kAllAbilities = ((1u << 7) - 1u) 64 }; 65 66 static SymbolFile *FindPlugin(lldb::ObjectFileSP objfile_sp); 67 68 // Constructors and Destructors 69 SymbolFile(lldb::ObjectFileSP objfile_sp) 70 : m_objfile_sp(std::move(objfile_sp)) {} 71 72 ~SymbolFile() override = default; 73 74 /// Get a mask of what this symbol file supports for the object file 75 /// that it was constructed with. 76 /// 77 /// Each symbol file gets to respond with a mask of abilities that 78 /// it supports for each object file. This happens when we are 79 /// trying to figure out which symbol file plug-in will get used 80 /// for a given object file. The plug-in that responds with the 81 /// best mix of "SymbolFile::Abilities" bits set, will get chosen to 82 /// be the symbol file parser. This allows each plug-in to check for 83 /// sections that contain data a symbol file plug-in would need. For 84 /// example the DWARF plug-in requires DWARF sections in a file that 85 /// contain debug information. If the DWARF plug-in doesn't find 86 /// these sections, it won't respond with many ability bits set, and 87 /// we will probably fall back to the symbol table SymbolFile plug-in 88 /// which uses any information in the symbol table. Also, plug-ins 89 /// might check for some specific symbols in a symbol table in the 90 /// case where the symbol table contains debug information (STABS 91 /// and COFF). Not a lot of work should happen in these functions 92 /// as the plug-in might not get selected due to another plug-in 93 /// having more abilities. Any initialization work should be saved 94 /// for "void SymbolFile::InitializeObject()" which will get called 95 /// on the SymbolFile object with the best set of abilities. 96 /// 97 /// \return 98 /// A uint32_t mask containing bits from the SymbolFile::Abilities 99 /// enumeration. Any bits that are set represent an ability that 100 /// this symbol plug-in can parse from the object file. 101 uint32_t GetAbilities() { 102 if (!m_calculated_abilities) { 103 m_abilities = CalculateAbilities(); 104 m_calculated_abilities = true; 105 } 106 107 return m_abilities; 108 } 109 110 virtual uint32_t CalculateAbilities() = 0; 111 112 /// Symbols file subclasses should override this to return the Module that 113 /// owns the TypeSystem that this symbol file modifies type information in. 114 virtual std::recursive_mutex &GetModuleMutex() const; 115 116 /// Initialize the SymbolFile object. 117 /// 118 /// The SymbolFile object with the best set of abilities (detected 119 /// in "uint32_t SymbolFile::GetAbilities()) will have this function 120 /// called if it is chosen to parse an object file. More complete 121 /// initialization can happen in this function which will get called 122 /// prior to any other functions in the SymbolFile protocol. 123 virtual void InitializeObject() {} 124 125 // Compile Unit function calls 126 // Approach 1 - iterator 127 uint32_t GetNumCompileUnits(); 128 lldb::CompUnitSP GetCompileUnitAtIndex(uint32_t idx); 129 130 Symtab *GetSymtab(); 131 132 virtual lldb::LanguageType ParseLanguage(CompileUnit &comp_unit) = 0; 133 /// Return the Xcode SDK comp_unit was compiled against. 134 virtual XcodeSDK ParseXcodeSDK(CompileUnit &comp_unit) { return {}; } 135 virtual size_t ParseFunctions(CompileUnit &comp_unit) = 0; 136 virtual bool ParseLineTable(CompileUnit &comp_unit) = 0; 137 virtual bool ParseDebugMacros(CompileUnit &comp_unit) = 0; 138 139 /// Apply a lambda to each external lldb::Module referenced by this 140 /// \p comp_unit. Recursively also descends into the referenced external 141 /// modules of any encountered compilation unit. 142 /// 143 /// This function can be used to traverse Clang -gmodules debug 144 /// information, which is stored in DWARF files separate from the 145 /// object files. 146 /// 147 /// \param comp_unit 148 /// When this SymbolFile consists of multiple auxilliary 149 /// SymbolFiles, for example, a Darwin debug map that references 150 /// multiple .o files, comp_unit helps choose the auxilliary 151 /// file. In most other cases comp_unit's symbol file is 152 /// identical with *this. 153 /// 154 /// \param[in] lambda 155 /// The lambda that should be applied to every function. The lambda can 156 /// return true if the iteration should be aborted earlier. 157 /// 158 /// \param visited_symbol_files 159 /// A set of SymbolFiles that were already visited to avoid 160 /// visiting one file more than once. 161 /// 162 /// \return 163 /// If the lambda early-exited, this function returns true to 164 /// propagate the early exit. 165 virtual bool ForEachExternalModule( 166 lldb_private::CompileUnit &comp_unit, 167 llvm::DenseSet<lldb_private::SymbolFile *> &visited_symbol_files, 168 llvm::function_ref<bool(Module &)> lambda) { 169 return false; 170 } 171 virtual bool ParseSupportFiles(CompileUnit &comp_unit, 172 FileSpecList &support_files) = 0; 173 virtual size_t ParseTypes(CompileUnit &comp_unit) = 0; 174 virtual bool ParseIsOptimized(CompileUnit &comp_unit) { return false; } 175 176 virtual bool 177 ParseImportedModules(const SymbolContext &sc, 178 std::vector<SourceModule> &imported_modules) = 0; 179 virtual size_t ParseBlocksRecursive(Function &func) = 0; 180 virtual size_t ParseVariablesForContext(const SymbolContext &sc) = 0; 181 virtual Type *ResolveTypeUID(lldb::user_id_t type_uid) = 0; 182 183 /// The characteristics of an array type. 184 struct ArrayInfo { 185 int64_t first_index = 0; 186 llvm::SmallVector<uint64_t, 1> element_orders; 187 uint32_t byte_stride = 0; 188 uint32_t bit_stride = 0; 189 }; 190 /// If \c type_uid points to an array type, return its characteristics. 191 /// To support variable-length array types, this function takes an 192 /// optional \p ExecutionContext. If \c exe_ctx is non-null, the 193 /// dynamic characteristics for that context are returned. 194 virtual llvm::Optional<ArrayInfo> 195 GetDynamicArrayInfoForUID(lldb::user_id_t type_uid, 196 const lldb_private::ExecutionContext *exe_ctx) = 0; 197 198 virtual bool CompleteType(CompilerType &compiler_type) = 0; 199 virtual void ParseDeclsForContext(CompilerDeclContext decl_ctx) {} 200 virtual CompilerDecl GetDeclForUID(lldb::user_id_t uid) { 201 return CompilerDecl(); 202 } 203 virtual CompilerDeclContext GetDeclContextForUID(lldb::user_id_t uid) { 204 return CompilerDeclContext(); 205 } 206 virtual CompilerDeclContext GetDeclContextContainingUID(lldb::user_id_t uid) { 207 return CompilerDeclContext(); 208 } 209 virtual uint32_t ResolveSymbolContext(const Address &so_addr, 210 lldb::SymbolContextItem resolve_scope, 211 SymbolContext &sc) = 0; 212 virtual uint32_t 213 ResolveSymbolContext(const SourceLocationSpec &src_location_spec, 214 lldb::SymbolContextItem resolve_scope, 215 SymbolContextList &sc_list); 216 217 virtual void DumpClangAST(Stream &s) {} 218 virtual void FindGlobalVariables(ConstString name, 219 const CompilerDeclContext &parent_decl_ctx, 220 uint32_t max_matches, 221 VariableList &variables); 222 virtual void FindGlobalVariables(const RegularExpression ®ex, 223 uint32_t max_matches, 224 VariableList &variables); 225 virtual void FindFunctions(ConstString name, 226 const CompilerDeclContext &parent_decl_ctx, 227 lldb::FunctionNameType name_type_mask, 228 bool include_inlines, SymbolContextList &sc_list); 229 virtual void FindFunctions(const RegularExpression ®ex, 230 bool include_inlines, SymbolContextList &sc_list); 231 virtual void 232 FindTypes(ConstString name, const CompilerDeclContext &parent_decl_ctx, 233 uint32_t max_matches, 234 llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files, 235 TypeMap &types); 236 237 /// Find types specified by a CompilerContextPattern. 238 /// \param languages 239 /// Only return results in these languages. 240 /// \param searched_symbol_files 241 /// Prevents one file from being visited multiple times. 242 virtual void 243 FindTypes(llvm::ArrayRef<CompilerContext> pattern, LanguageSet languages, 244 llvm::DenseSet<lldb_private::SymbolFile *> &searched_symbol_files, 245 TypeMap &types); 246 247 virtual void 248 GetMangledNamesForFunction(const std::string &scope_qualified_name, 249 std::vector<ConstString> &mangled_names); 250 251 virtual void GetTypes(lldb_private::SymbolContextScope *sc_scope, 252 lldb::TypeClass type_mask, 253 lldb_private::TypeList &type_list) = 0; 254 255 virtual void PreloadSymbols(); 256 257 virtual llvm::Expected<lldb_private::TypeSystem &> 258 GetTypeSystemForLanguage(lldb::LanguageType language); 259 260 virtual CompilerDeclContext 261 FindNamespace(ConstString name, const CompilerDeclContext &parent_decl_ctx) { 262 return CompilerDeclContext(); 263 } 264 265 ObjectFile *GetObjectFile() { return m_objfile_sp.get(); } 266 const ObjectFile *GetObjectFile() const { return m_objfile_sp.get(); } 267 ObjectFile *GetMainObjectFile(); 268 269 virtual std::vector<std::unique_ptr<CallEdge>> 270 ParseCallEdgesInFunction(UserID func_id) { 271 return {}; 272 } 273 274 virtual void AddSymbols(Symtab &symtab) {} 275 276 /// Notify the SymbolFile that the file addresses in the Sections 277 /// for this module have been changed. 278 virtual void SectionFileAddressesChanged(); 279 280 struct RegisterInfoResolver { 281 virtual ~RegisterInfoResolver(); // anchor 282 283 virtual const RegisterInfo *ResolveName(llvm::StringRef name) const = 0; 284 virtual const RegisterInfo *ResolveNumber(lldb::RegisterKind kind, 285 uint32_t number) const = 0; 286 }; 287 virtual lldb::UnwindPlanSP 288 GetUnwindPlan(const Address &address, const RegisterInfoResolver &resolver) { 289 return nullptr; 290 } 291 292 /// Return the number of stack bytes taken up by the parameters to this 293 /// function. 294 virtual llvm::Expected<lldb::addr_t> GetParameterStackSize(Symbol &symbol) { 295 return llvm::createStringError(make_error_code(llvm::errc::not_supported), 296 "Operation not supported."); 297 } 298 299 virtual void Dump(Stream &s); 300 301 /// Metrics gathering functions 302 303 /// Return the size in bytes of all debug information in the symbol file. 304 /// 305 /// If the debug information is contained in sections of an ObjectFile, then 306 /// this call should add the size of all sections that contain debug 307 /// information. Symbols the symbol tables are not considered debug 308 /// information for this call to make it easy and quick for this number to be 309 /// calculated. If the symbol file is all debug information, the size of the 310 /// entire file should be returned. The default implementation of this 311 /// function will iterate over all sections in a module and add up their 312 /// debug info only section byte sizes. 313 virtual uint64_t GetDebugInfoSize(); 314 315 /// Return the time taken to parse the debug information. 316 /// 317 /// \returns 0.0 if no information has been parsed or if there is 318 /// no computational cost to parsing the debug information. 319 virtual StatsDuration::Duration GetDebugInfoParseTime() { return {}; } 320 321 /// Return the time it took to index the debug information in the object 322 /// file. 323 /// 324 /// \returns 0.0 if the file doesn't need to be indexed or if it 325 /// hasn't been indexed yet, or a valid duration if it has. 326 virtual StatsDuration::Duration GetDebugInfoIndexTime() { return {}; } 327 328 /// Accessors for the bool that indicates if the debug info index was loaded 329 /// from, or saved to the module index cache. 330 /// 331 /// In statistics it is handy to know if a module's debug info was loaded from 332 /// or saved to the cache. When the debug info index is loaded from the cache 333 /// startup times can be faster. When the cache is enabled and the debug info 334 /// index is saved to the cache, debug sessions can be slower. These accessors 335 /// can be accessed by the statistics and emitted to help track these costs. 336 /// \{ 337 bool GetDebugInfoIndexWasLoadedFromCache() const { 338 return m_index_was_loaded_from_cache; 339 } 340 void SetDebugInfoIndexWasLoadedFromCache() { 341 m_index_was_loaded_from_cache = true; 342 } 343 bool GetDebugInfoIndexWasSavedToCache() const { 344 return m_index_was_saved_to_cache; 345 } 346 void SetDebugInfoIndexWasSavedToCache() { 347 m_index_was_saved_to_cache = true; 348 } 349 /// \} 350 351 protected: 352 void AssertModuleLock(); 353 virtual uint32_t CalculateNumCompileUnits() = 0; 354 virtual lldb::CompUnitSP ParseCompileUnitAtIndex(uint32_t idx) = 0; 355 virtual TypeList &GetTypeList() { return m_type_list; } 356 357 void SetCompileUnitAtIndex(uint32_t idx, const lldb::CompUnitSP &cu_sp); 358 359 lldb::ObjectFileSP m_objfile_sp; // Keep a reference to the object file in 360 // case it isn't the same as the module 361 // object file (debug symbols in a separate 362 // file) 363 llvm::Optional<std::vector<lldb::CompUnitSP>> m_compile_units; 364 TypeList m_type_list; 365 Symtab *m_symtab = nullptr; 366 uint32_t m_abilities = 0; 367 bool m_calculated_abilities = false; 368 bool m_index_was_loaded_from_cache = false; 369 bool m_index_was_saved_to_cache = false; 370 371 private: 372 SymbolFile(const SymbolFile &) = delete; 373 const SymbolFile &operator=(const SymbolFile &) = delete; 374 }; 375 376 } // namespace lldb_private 377 378 #endif // LLDB_SYMBOL_SYMBOLFILE_H 379