1 //===- Wasm.h - Wasm object file implementation -----------------*- 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 // This file declares the WasmObjectFile class, which implements the ObjectFile 10 // interface for Wasm files. 11 // 12 // See: https://github.com/WebAssembly/design/blob/master/BinaryEncoding.md 13 // 14 //===----------------------------------------------------------------------===// 15 16 #ifndef LLVM_OBJECT_WASM_H 17 #define LLVM_OBJECT_WASM_H 18 19 #include "llvm/ADT/ArrayRef.h" 20 #include "llvm/ADT/StringRef.h" 21 #include "llvm/BinaryFormat/Wasm.h" 22 #include "llvm/Config/llvm-config.h" 23 #include "llvm/MC/MCSymbolWasm.h" 24 #include "llvm/Object/Binary.h" 25 #include "llvm/Object/ObjectFile.h" 26 #include "llvm/Support/Error.h" 27 #include "llvm/Support/MemoryBuffer.h" 28 #include <cstddef> 29 #include <cstdint> 30 #include <vector> 31 32 namespace llvm { 33 namespace object { 34 35 class WasmSymbol { 36 public: 37 WasmSymbol(const wasm::WasmSymbolInfo &Info, 38 const wasm::WasmGlobalType *GlobalType, 39 const wasm::WasmTableType *TableType, 40 const wasm::WasmEventType *EventType, 41 const wasm::WasmSignature *Signature) 42 : Info(Info), GlobalType(GlobalType), TableType(TableType), 43 EventType(EventType), Signature(Signature) {} 44 45 const wasm::WasmSymbolInfo &Info; 46 const wasm::WasmGlobalType *GlobalType; 47 const wasm::WasmTableType *TableType; 48 const wasm::WasmEventType *EventType; 49 const wasm::WasmSignature *Signature; 50 51 bool isTypeFunction() const { 52 return Info.Kind == wasm::WASM_SYMBOL_TYPE_FUNCTION; 53 } 54 55 bool isTypeTable() const { return Info.Kind == wasm::WASM_SYMBOL_TYPE_TABLE; } 56 57 bool isTypeData() const { return Info.Kind == wasm::WASM_SYMBOL_TYPE_DATA; } 58 59 bool isTypeGlobal() const { 60 return Info.Kind == wasm::WASM_SYMBOL_TYPE_GLOBAL; 61 } 62 63 bool isTypeSection() const { 64 return Info.Kind == wasm::WASM_SYMBOL_TYPE_SECTION; 65 } 66 67 bool isTypeEvent() const { return Info.Kind == wasm::WASM_SYMBOL_TYPE_EVENT; } 68 69 bool isDefined() const { return !isUndefined(); } 70 71 bool isUndefined() const { 72 return (Info.Flags & wasm::WASM_SYMBOL_UNDEFINED) != 0; 73 } 74 75 bool isBindingWeak() const { 76 return getBinding() == wasm::WASM_SYMBOL_BINDING_WEAK; 77 } 78 79 bool isBindingGlobal() const { 80 return getBinding() == wasm::WASM_SYMBOL_BINDING_GLOBAL; 81 } 82 83 bool isBindingLocal() const { 84 return getBinding() == wasm::WASM_SYMBOL_BINDING_LOCAL; 85 } 86 87 unsigned getBinding() const { 88 return Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK; 89 } 90 91 bool isHidden() const { 92 return getVisibility() == wasm::WASM_SYMBOL_VISIBILITY_HIDDEN; 93 } 94 95 unsigned getVisibility() const { 96 return Info.Flags & wasm::WASM_SYMBOL_VISIBILITY_MASK; 97 } 98 99 void print(raw_ostream &Out) const; 100 101 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 102 LLVM_DUMP_METHOD void dump() const; 103 #endif 104 }; 105 106 struct WasmSection { 107 WasmSection() = default; 108 109 uint32_t Type = 0; // Section type (See below) 110 uint32_t Offset = 0; // Offset with in the file 111 StringRef Name; // Section name (User-defined sections only) 112 uint32_t Comdat = UINT32_MAX; // From the "comdat info" section 113 ArrayRef<uint8_t> Content; // Section content 114 std::vector<wasm::WasmRelocation> Relocations; // Relocations for this section 115 }; 116 117 struct WasmSegment { 118 uint32_t SectionOffset; 119 wasm::WasmDataSegment Data; 120 }; 121 122 class WasmObjectFile : public ObjectFile { 123 124 public: 125 WasmObjectFile(MemoryBufferRef Object, Error &Err); 126 127 const wasm::WasmObjectHeader &getHeader() const; 128 const WasmSymbol &getWasmSymbol(const DataRefImpl &Symb) const; 129 const WasmSymbol &getWasmSymbol(const SymbolRef &Symbol) const; 130 const WasmSection &getWasmSection(const SectionRef &Section) const; 131 const wasm::WasmRelocation &getWasmRelocation(const RelocationRef &Ref) const; 132 133 static bool classof(const Binary *v) { return v->isWasm(); } 134 135 const wasm::WasmDylinkInfo &dylinkInfo() const { return DylinkInfo; } 136 const wasm::WasmProducerInfo &getProducerInfo() const { return ProducerInfo; } 137 ArrayRef<wasm::WasmFeatureEntry> getTargetFeatures() const { 138 return TargetFeatures; 139 } 140 ArrayRef<wasm::WasmSignature> types() const { return Signatures; } 141 ArrayRef<uint32_t> functionTypes() const { return FunctionTypes; } 142 ArrayRef<wasm::WasmImport> imports() const { return Imports; } 143 ArrayRef<wasm::WasmTable> tables() const { return Tables; } 144 ArrayRef<wasm::WasmLimits> memories() const { return Memories; } 145 ArrayRef<wasm::WasmGlobal> globals() const { return Globals; } 146 ArrayRef<wasm::WasmEvent> events() const { return Events; } 147 ArrayRef<wasm::WasmExport> exports() const { return Exports; } 148 ArrayRef<WasmSymbol> syms() const { return Symbols; } 149 const wasm::WasmLinkingData &linkingData() const { return LinkingData; } 150 uint32_t getNumberOfSymbols() const { return Symbols.size(); } 151 ArrayRef<wasm::WasmElemSegment> elements() const { return ElemSegments; } 152 ArrayRef<WasmSegment> dataSegments() const { return DataSegments; } 153 ArrayRef<wasm::WasmFunction> functions() const { return Functions; } 154 ArrayRef<wasm::WasmDebugName> debugNames() const { return DebugNames; } 155 uint32_t startFunction() const { return StartFunction; } 156 uint32_t getNumImportedGlobals() const { return NumImportedGlobals; } 157 uint32_t getNumImportedTables() const { return NumImportedTables; } 158 uint32_t getNumImportedFunctions() const { return NumImportedFunctions; } 159 uint32_t getNumImportedEvents() const { return NumImportedEvents; } 160 uint32_t getNumSections() const { return Sections.size(); } 161 void moveSymbolNext(DataRefImpl &Symb) const override; 162 163 Expected<uint32_t> getSymbolFlags(DataRefImpl Symb) const override; 164 165 basic_symbol_iterator symbol_begin() const override; 166 167 basic_symbol_iterator symbol_end() const override; 168 Expected<StringRef> getSymbolName(DataRefImpl Symb) const override; 169 170 Expected<uint64_t> getSymbolAddress(DataRefImpl Symb) const override; 171 uint64_t getWasmSymbolValue(const WasmSymbol &Sym) const; 172 uint64_t getSymbolValueImpl(DataRefImpl Symb) const override; 173 uint32_t getSymbolAlignment(DataRefImpl Symb) const override; 174 uint64_t getCommonSymbolSizeImpl(DataRefImpl Symb) const override; 175 Expected<SymbolRef::Type> getSymbolType(DataRefImpl Symb) const override; 176 Expected<section_iterator> getSymbolSection(DataRefImpl Symb) const override; 177 uint32_t getSymbolSectionId(SymbolRef Sym) const; 178 179 // Overrides from SectionRef. 180 void moveSectionNext(DataRefImpl &Sec) const override; 181 Expected<StringRef> getSectionName(DataRefImpl Sec) const override; 182 uint64_t getSectionAddress(DataRefImpl Sec) const override; 183 uint64_t getSectionIndex(DataRefImpl Sec) const override; 184 uint64_t getSectionSize(DataRefImpl Sec) const override; 185 Expected<ArrayRef<uint8_t>> 186 getSectionContents(DataRefImpl Sec) const override; 187 uint64_t getSectionAlignment(DataRefImpl Sec) const override; 188 bool isSectionCompressed(DataRefImpl Sec) const override; 189 bool isSectionText(DataRefImpl Sec) const override; 190 bool isSectionData(DataRefImpl Sec) const override; 191 bool isSectionBSS(DataRefImpl Sec) const override; 192 bool isSectionVirtual(DataRefImpl Sec) const override; 193 relocation_iterator section_rel_begin(DataRefImpl Sec) const override; 194 relocation_iterator section_rel_end(DataRefImpl Sec) const override; 195 196 // Overrides from RelocationRef. 197 void moveRelocationNext(DataRefImpl &Rel) const override; 198 uint64_t getRelocationOffset(DataRefImpl Rel) const override; 199 symbol_iterator getRelocationSymbol(DataRefImpl Rel) const override; 200 uint64_t getRelocationType(DataRefImpl Rel) const override; 201 void getRelocationTypeName(DataRefImpl Rel, 202 SmallVectorImpl<char> &Result) const override; 203 204 section_iterator section_begin() const override; 205 section_iterator section_end() const override; 206 uint8_t getBytesInAddress() const override; 207 StringRef getFileFormatName() const override; 208 Triple::ArchType getArch() const override; 209 SubtargetFeatures getFeatures() const override; 210 bool isRelocatableObject() const override; 211 bool isSharedObject() const; 212 213 struct ReadContext { 214 const uint8_t *Start; 215 const uint8_t *Ptr; 216 const uint8_t *End; 217 }; 218 219 private: 220 bool isValidFunctionIndex(uint32_t Index) const; 221 bool isDefinedFunctionIndex(uint32_t Index) const; 222 bool isValidGlobalIndex(uint32_t Index) const; 223 bool isValidTableNumber(uint32_t Index) const; 224 bool isDefinedGlobalIndex(uint32_t Index) const; 225 bool isDefinedTableNumber(uint32_t Index) const; 226 bool isValidEventIndex(uint32_t Index) const; 227 bool isDefinedEventIndex(uint32_t Index) const; 228 bool isValidFunctionSymbol(uint32_t Index) const; 229 bool isValidTableSymbol(uint32_t Index) const; 230 bool isValidGlobalSymbol(uint32_t Index) const; 231 bool isValidEventSymbol(uint32_t Index) const; 232 bool isValidDataSymbol(uint32_t Index) const; 233 bool isValidSectionSymbol(uint32_t Index) const; 234 wasm::WasmFunction &getDefinedFunction(uint32_t Index); 235 const wasm::WasmFunction &getDefinedFunction(uint32_t Index) const; 236 wasm::WasmGlobal &getDefinedGlobal(uint32_t Index); 237 wasm::WasmEvent &getDefinedEvent(uint32_t Index); 238 239 const WasmSection &getWasmSection(DataRefImpl Ref) const; 240 const wasm::WasmRelocation &getWasmRelocation(DataRefImpl Ref) const; 241 uint32_t getSymbolSectionIdImpl(const WasmSymbol &Symb) const; 242 243 Error parseSection(WasmSection &Sec); 244 Error parseCustomSection(WasmSection &Sec, ReadContext &Ctx); 245 246 // Standard section types 247 Error parseTypeSection(ReadContext &Ctx); 248 Error parseImportSection(ReadContext &Ctx); 249 Error parseFunctionSection(ReadContext &Ctx); 250 Error parseTableSection(ReadContext &Ctx); 251 Error parseMemorySection(ReadContext &Ctx); 252 Error parseEventSection(ReadContext &Ctx); 253 Error parseGlobalSection(ReadContext &Ctx); 254 Error parseExportSection(ReadContext &Ctx); 255 Error parseStartSection(ReadContext &Ctx); 256 Error parseElemSection(ReadContext &Ctx); 257 Error parseCodeSection(ReadContext &Ctx); 258 Error parseDataSection(ReadContext &Ctx); 259 Error parseDataCountSection(ReadContext &Ctx); 260 261 // Custom section types 262 Error parseDylinkSection(ReadContext &Ctx); 263 Error parseNameSection(ReadContext &Ctx); 264 Error parseLinkingSection(ReadContext &Ctx); 265 Error parseLinkingSectionSymtab(ReadContext &Ctx); 266 Error parseLinkingSectionComdat(ReadContext &Ctx); 267 Error parseProducersSection(ReadContext &Ctx); 268 Error parseTargetFeaturesSection(ReadContext &Ctx); 269 Error parseRelocSection(StringRef Name, ReadContext &Ctx); 270 271 wasm::WasmObjectHeader Header; 272 std::vector<WasmSection> Sections; 273 wasm::WasmDylinkInfo DylinkInfo; 274 wasm::WasmProducerInfo ProducerInfo; 275 std::vector<wasm::WasmFeatureEntry> TargetFeatures; 276 std::vector<wasm::WasmSignature> Signatures; 277 std::vector<uint32_t> FunctionTypes; 278 std::vector<wasm::WasmTable> Tables; 279 std::vector<wasm::WasmLimits> Memories; 280 std::vector<wasm::WasmGlobal> Globals; 281 std::vector<wasm::WasmEvent> Events; 282 std::vector<wasm::WasmImport> Imports; 283 std::vector<wasm::WasmExport> Exports; 284 std::vector<wasm::WasmElemSegment> ElemSegments; 285 std::vector<WasmSegment> DataSegments; 286 llvm::Optional<size_t> DataCount; 287 std::vector<wasm::WasmFunction> Functions; 288 std::vector<WasmSymbol> Symbols; 289 std::vector<wasm::WasmDebugName> DebugNames; 290 uint32_t StartFunction = -1; 291 bool HasLinkingSection = false; 292 bool HasDylinkSection = false; 293 bool SeenCodeSection = false; 294 bool HasMemory64 = false; 295 wasm::WasmLinkingData LinkingData; 296 uint32_t NumImportedGlobals = 0; 297 uint32_t NumImportedTables = 0; 298 uint32_t NumImportedFunctions = 0; 299 uint32_t NumImportedEvents = 0; 300 uint32_t CodeSection = 0; 301 uint32_t DataSection = 0; 302 uint32_t EventSection = 0; 303 uint32_t GlobalSection = 0; 304 uint32_t TableSection = 0; 305 }; 306 307 class WasmSectionOrderChecker { 308 public: 309 // We define orders for all core wasm sections and known custom sections. 310 enum : int { 311 // Sentinel, must be zero 312 WASM_SEC_ORDER_NONE = 0, 313 314 // Core sections 315 WASM_SEC_ORDER_TYPE, 316 WASM_SEC_ORDER_IMPORT, 317 WASM_SEC_ORDER_FUNCTION, 318 WASM_SEC_ORDER_TABLE, 319 WASM_SEC_ORDER_MEMORY, 320 WASM_SEC_ORDER_EVENT, 321 WASM_SEC_ORDER_GLOBAL, 322 WASM_SEC_ORDER_EXPORT, 323 WASM_SEC_ORDER_START, 324 WASM_SEC_ORDER_ELEM, 325 WASM_SEC_ORDER_DATACOUNT, 326 WASM_SEC_ORDER_CODE, 327 WASM_SEC_ORDER_DATA, 328 329 // Custom sections 330 // "dylink" should be the very first section in the module 331 WASM_SEC_ORDER_DYLINK, 332 // "linking" section requires DATA section in order to validate data symbols 333 WASM_SEC_ORDER_LINKING, 334 // Must come after "linking" section in order to validate reloc indexes. 335 WASM_SEC_ORDER_RELOC, 336 // "name" section must appear after DATA. Comes after "linking" to allow 337 // symbol table to set default function name. 338 WASM_SEC_ORDER_NAME, 339 // "producers" section must appear after "name" section. 340 WASM_SEC_ORDER_PRODUCERS, 341 // "target_features" section must appear after producers section 342 WASM_SEC_ORDER_TARGET_FEATURES, 343 344 // Must be last 345 WASM_NUM_SEC_ORDERS 346 347 }; 348 349 // Sections that may or may not be present, but cannot be predecessors 350 static int DisallowedPredecessors[WASM_NUM_SEC_ORDERS][WASM_NUM_SEC_ORDERS]; 351 352 bool isValidSectionOrder(unsigned ID, StringRef CustomSectionName = ""); 353 354 private: 355 bool Seen[WASM_NUM_SEC_ORDERS] = {}; // Sections that have been seen already 356 357 // Returns -1 for unknown sections. 358 int getSectionOrder(unsigned ID, StringRef CustomSectionName = ""); 359 }; 360 361 } // end namespace object 362 363 inline raw_ostream &operator<<(raw_ostream &OS, const object::WasmSymbol &Sym) { 364 Sym.print(OS); 365 return OS; 366 } 367 368 } // end namespace llvm 369 370 #endif // LLVM_OBJECT_WASM_H 371
Indexes created Tue Feb 24 08:35:24 UTC 2026