1 //===- WasmObjectFile.cpp - Wasm object file implementation ---------------===// 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 #include "llvm/ADT/ArrayRef.h" 10 #include "llvm/ADT/DenseSet.h" 11 #include "llvm/ADT/STLExtras.h" 12 #include "llvm/ADT/SmallSet.h" 13 #include "llvm/ADT/StringRef.h" 14 #include "llvm/ADT/StringSet.h" 15 #include "llvm/ADT/StringSwitch.h" 16 #include "llvm/ADT/Triple.h" 17 #include "llvm/BinaryFormat/Wasm.h" 18 #include "llvm/MC/SubtargetFeature.h" 19 #include "llvm/Object/Binary.h" 20 #include "llvm/Object/Error.h" 21 #include "llvm/Object/ObjectFile.h" 22 #include "llvm/Object/SymbolicFile.h" 23 #include "llvm/Object/Wasm.h" 24 #include "llvm/Support/Endian.h" 25 #include "llvm/Support/Error.h" 26 #include "llvm/Support/ErrorHandling.h" 27 #include "llvm/Support/LEB128.h" 28 #include "llvm/Support/ScopedPrinter.h" 29 #include <algorithm> 30 #include <cassert> 31 #include <cstdint> 32 #include <cstring> 33 #include <system_error> 34 35 #define DEBUG_TYPE "wasm-object" 36 37 using namespace llvm; 38 using namespace object; 39 40 void WasmSymbol::print(raw_ostream &Out) const { 41 Out << "Name=" << Info.Name 42 << ", Kind=" << toString(wasm::WasmSymbolType(Info.Kind)) 43 << ", Flags=" << Info.Flags; 44 if (!isTypeData()) { 45 Out << ", ElemIndex=" << Info.ElementIndex; 46 } else if (isDefined()) { 47 Out << ", Segment=" << Info.DataRef.Segment; 48 Out << ", Offset=" << Info.DataRef.Offset; 49 Out << ", Size=" << Info.DataRef.Size; 50 } 51 } 52 53 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 54 LLVM_DUMP_METHOD void WasmSymbol::dump() const { print(dbgs()); } 55 #endif 56 57 Expected<std::unique_ptr<WasmObjectFile>> 58 ObjectFile::createWasmObjectFile(MemoryBufferRef Buffer) { 59 Error Err = Error::success(); 60 auto ObjectFile = std::make_unique<WasmObjectFile>(Buffer, Err); 61 if (Err) 62 return std::move(Err); 63 64 return std::move(ObjectFile); 65 } 66 67 #define VARINT7_MAX ((1 << 7) - 1) 68 #define VARINT7_MIN (-(1 << 7)) 69 #define VARUINT7_MAX (1 << 7) 70 #define VARUINT1_MAX (1) 71 72 static uint8_t readUint8(WasmObjectFile::ReadContext &Ctx) { 73 if (Ctx.Ptr == Ctx.End) 74 report_fatal_error("EOF while reading uint8"); 75 return *Ctx.Ptr++; 76 } 77 78 static uint32_t readUint32(WasmObjectFile::ReadContext &Ctx) { 79 if (Ctx.Ptr + 4 > Ctx.End) 80 report_fatal_error("EOF while reading uint32"); 81 uint32_t Result = support::endian::read32le(Ctx.Ptr); 82 Ctx.Ptr += 4; 83 return Result; 84 } 85 86 static int32_t readFloat32(WasmObjectFile::ReadContext &Ctx) { 87 if (Ctx.Ptr + 4 > Ctx.End) 88 report_fatal_error("EOF while reading float64"); 89 int32_t Result = 0; 90 memcpy(&Result, Ctx.Ptr, sizeof(Result)); 91 Ctx.Ptr += sizeof(Result); 92 return Result; 93 } 94 95 static int64_t readFloat64(WasmObjectFile::ReadContext &Ctx) { 96 if (Ctx.Ptr + 8 > Ctx.End) 97 report_fatal_error("EOF while reading float64"); 98 int64_t Result = 0; 99 memcpy(&Result, Ctx.Ptr, sizeof(Result)); 100 Ctx.Ptr += sizeof(Result); 101 return Result; 102 } 103 104 static uint64_t readULEB128(WasmObjectFile::ReadContext &Ctx) { 105 unsigned Count; 106 const char *Error = nullptr; 107 uint64_t Result = decodeULEB128(Ctx.Ptr, &Count, Ctx.End, &Error); 108 if (Error) 109 report_fatal_error(Error); 110 Ctx.Ptr += Count; 111 return Result; 112 } 113 114 static StringRef readString(WasmObjectFile::ReadContext &Ctx) { 115 uint32_t StringLen = readULEB128(Ctx); 116 if (Ctx.Ptr + StringLen > Ctx.End) 117 report_fatal_error("EOF while reading string"); 118 StringRef Return = 119 StringRef(reinterpret_cast<const char *>(Ctx.Ptr), StringLen); 120 Ctx.Ptr += StringLen; 121 return Return; 122 } 123 124 static int64_t readLEB128(WasmObjectFile::ReadContext &Ctx) { 125 unsigned Count; 126 const char *Error = nullptr; 127 uint64_t Result = decodeSLEB128(Ctx.Ptr, &Count, Ctx.End, &Error); 128 if (Error) 129 report_fatal_error(Error); 130 Ctx.Ptr += Count; 131 return Result; 132 } 133 134 static uint8_t readVaruint1(WasmObjectFile::ReadContext &Ctx) { 135 int64_t Result = readLEB128(Ctx); 136 if (Result > VARUINT1_MAX || Result < 0) 137 report_fatal_error("LEB is outside Varuint1 range"); 138 return Result; 139 } 140 141 static int32_t readVarint32(WasmObjectFile::ReadContext &Ctx) { 142 int64_t Result = readLEB128(Ctx); 143 if (Result > INT32_MAX || Result < INT32_MIN) 144 report_fatal_error("LEB is outside Varint32 range"); 145 return Result; 146 } 147 148 static uint32_t readVaruint32(WasmObjectFile::ReadContext &Ctx) { 149 uint64_t Result = readULEB128(Ctx); 150 if (Result > UINT32_MAX) 151 report_fatal_error("LEB is outside Varuint32 range"); 152 return Result; 153 } 154 155 static int64_t readVarint64(WasmObjectFile::ReadContext &Ctx) { 156 return readLEB128(Ctx); 157 } 158 159 static uint64_t readVaruint64(WasmObjectFile::ReadContext &Ctx) { 160 return readULEB128(Ctx); 161 } 162 163 static uint8_t readOpcode(WasmObjectFile::ReadContext &Ctx) { 164 return readUint8(Ctx); 165 } 166 167 static Error readInitExpr(wasm::WasmInitExpr &Expr, 168 WasmObjectFile::ReadContext &Ctx) { 169 Expr.Opcode = readOpcode(Ctx); 170 171 switch (Expr.Opcode) { 172 case wasm::WASM_OPCODE_I32_CONST: 173 Expr.Value.Int32 = readVarint32(Ctx); 174 break; 175 case wasm::WASM_OPCODE_I64_CONST: 176 Expr.Value.Int64 = readVarint64(Ctx); 177 break; 178 case wasm::WASM_OPCODE_F32_CONST: 179 Expr.Value.Float32 = readFloat32(Ctx); 180 break; 181 case wasm::WASM_OPCODE_F64_CONST: 182 Expr.Value.Float64 = readFloat64(Ctx); 183 break; 184 case wasm::WASM_OPCODE_GLOBAL_GET: 185 Expr.Value.Global = readULEB128(Ctx); 186 break; 187 case wasm::WASM_OPCODE_REF_NULL: { 188 wasm::ValType Ty = static_cast<wasm::ValType>(readULEB128(Ctx)); 189 if (Ty != wasm::ValType::EXTERNREF) { 190 return make_error<GenericBinaryError>("Invalid type for ref.null", 191 object_error::parse_failed); 192 } 193 break; 194 } 195 default: 196 return make_error<GenericBinaryError>("Invalid opcode in init_expr", 197 object_error::parse_failed); 198 } 199 200 uint8_t EndOpcode = readOpcode(Ctx); 201 if (EndOpcode != wasm::WASM_OPCODE_END) { 202 return make_error<GenericBinaryError>("Invalid init_expr", 203 object_error::parse_failed); 204 } 205 return Error::success(); 206 } 207 208 static wasm::WasmLimits readLimits(WasmObjectFile::ReadContext &Ctx) { 209 wasm::WasmLimits Result; 210 Result.Flags = readVaruint32(Ctx); 211 Result.Initial = readVaruint64(Ctx); 212 if (Result.Flags & wasm::WASM_LIMITS_FLAG_HAS_MAX) 213 Result.Maximum = readVaruint64(Ctx); 214 return Result; 215 } 216 217 static wasm::WasmTable readTable(WasmObjectFile::ReadContext &Ctx) { 218 wasm::WasmTable Table; 219 Table.ElemType = readUint8(Ctx); 220 Table.Limits = readLimits(Ctx); 221 return Table; 222 } 223 224 static Error readSection(WasmSection &Section, WasmObjectFile::ReadContext &Ctx, 225 WasmSectionOrderChecker &Checker) { 226 Section.Offset = Ctx.Ptr - Ctx.Start; 227 Section.Type = readUint8(Ctx); 228 LLVM_DEBUG(dbgs() << "readSection type=" << Section.Type << "\n"); 229 uint32_t Size = readVaruint32(Ctx); 230 if (Size == 0) 231 return make_error<StringError>("Zero length section", 232 object_error::parse_failed); 233 if (Ctx.Ptr + Size > Ctx.End) 234 return make_error<StringError>("Section too large", 235 object_error::parse_failed); 236 if (Section.Type == wasm::WASM_SEC_CUSTOM) { 237 WasmObjectFile::ReadContext SectionCtx; 238 SectionCtx.Start = Ctx.Ptr; 239 SectionCtx.Ptr = Ctx.Ptr; 240 SectionCtx.End = Ctx.Ptr + Size; 241 242 Section.Name = readString(SectionCtx); 243 244 uint32_t SectionNameSize = SectionCtx.Ptr - SectionCtx.Start; 245 Ctx.Ptr += SectionNameSize; 246 Size -= SectionNameSize; 247 } 248 249 if (!Checker.isValidSectionOrder(Section.Type, Section.Name)) { 250 return make_error<StringError>("Out of order section type: " + 251 llvm::to_string(Section.Type), 252 object_error::parse_failed); 253 } 254 255 Section.Content = ArrayRef<uint8_t>(Ctx.Ptr, Size); 256 Ctx.Ptr += Size; 257 return Error::success(); 258 } 259 260 WasmObjectFile::WasmObjectFile(MemoryBufferRef Buffer, Error &Err) 261 : ObjectFile(Binary::ID_Wasm, Buffer) { 262 ErrorAsOutParameter ErrAsOutParam(&Err); 263 Header.Magic = getData().substr(0, 4); 264 if (Header.Magic != StringRef("\0asm", 4)) { 265 Err = 266 make_error<StringError>("Bad magic number", object_error::parse_failed); 267 return; 268 } 269 270 ReadContext Ctx; 271 Ctx.Start = getData().bytes_begin(); 272 Ctx.Ptr = Ctx.Start + 4; 273 Ctx.End = Ctx.Start + getData().size(); 274 275 if (Ctx.Ptr + 4 > Ctx.End) { 276 Err = make_error<StringError>("Missing version number", 277 object_error::parse_failed); 278 return; 279 } 280 281 Header.Version = readUint32(Ctx); 282 if (Header.Version != wasm::WasmVersion) { 283 Err = make_error<StringError>("Bad version number", 284 object_error::parse_failed); 285 return; 286 } 287 288 WasmSection Sec; 289 WasmSectionOrderChecker Checker; 290 while (Ctx.Ptr < Ctx.End) { 291 if ((Err = readSection(Sec, Ctx, Checker))) 292 return; 293 if ((Err = parseSection(Sec))) 294 return; 295 296 Sections.push_back(Sec); 297 } 298 } 299 300 Error WasmObjectFile::parseSection(WasmSection &Sec) { 301 ReadContext Ctx; 302 Ctx.Start = Sec.Content.data(); 303 Ctx.End = Ctx.Start + Sec.Content.size(); 304 Ctx.Ptr = Ctx.Start; 305 switch (Sec.Type) { 306 case wasm::WASM_SEC_CUSTOM: 307 return parseCustomSection(Sec, Ctx); 308 case wasm::WASM_SEC_TYPE: 309 return parseTypeSection(Ctx); 310 case wasm::WASM_SEC_IMPORT: 311 return parseImportSection(Ctx); 312 case wasm::WASM_SEC_FUNCTION: 313 return parseFunctionSection(Ctx); 314 case wasm::WASM_SEC_TABLE: 315 return parseTableSection(Ctx); 316 case wasm::WASM_SEC_MEMORY: 317 return parseMemorySection(Ctx); 318 case wasm::WASM_SEC_EVENT: 319 return parseEventSection(Ctx); 320 case wasm::WASM_SEC_GLOBAL: 321 return parseGlobalSection(Ctx); 322 case wasm::WASM_SEC_EXPORT: 323 return parseExportSection(Ctx); 324 case wasm::WASM_SEC_START: 325 return parseStartSection(Ctx); 326 case wasm::WASM_SEC_ELEM: 327 return parseElemSection(Ctx); 328 case wasm::WASM_SEC_CODE: 329 return parseCodeSection(Ctx); 330 case wasm::WASM_SEC_DATA: 331 return parseDataSection(Ctx); 332 case wasm::WASM_SEC_DATACOUNT: 333 return parseDataCountSection(Ctx); 334 default: 335 return make_error<GenericBinaryError>( 336 "Invalid section type: " + Twine(Sec.Type), object_error::parse_failed); 337 } 338 } 339 340 Error WasmObjectFile::parseDylinkSection(ReadContext &Ctx) { 341 // See https://github.com/WebAssembly/tool-conventions/blob/master/DynamicLinking.md 342 HasDylinkSection = true; 343 DylinkInfo.MemorySize = readVaruint32(Ctx); 344 DylinkInfo.MemoryAlignment = readVaruint32(Ctx); 345 DylinkInfo.TableSize = readVaruint32(Ctx); 346 DylinkInfo.TableAlignment = readVaruint32(Ctx); 347 uint32_t Count = readVaruint32(Ctx); 348 while (Count--) { 349 DylinkInfo.Needed.push_back(readString(Ctx)); 350 } 351 if (Ctx.Ptr != Ctx.End) 352 return make_error<GenericBinaryError>("dylink section ended prematurely", 353 object_error::parse_failed); 354 return Error::success(); 355 } 356 357 Error WasmObjectFile::parseNameSection(ReadContext &Ctx) { 358 llvm::DenseSet<uint64_t> Seen; 359 if (FunctionTypes.size() && !SeenCodeSection) { 360 return make_error<GenericBinaryError>("Names must come after code section", 361 object_error::parse_failed); 362 } 363 364 while (Ctx.Ptr < Ctx.End) { 365 uint8_t Type = readUint8(Ctx); 366 uint32_t Size = readVaruint32(Ctx); 367 const uint8_t *SubSectionEnd = Ctx.Ptr + Size; 368 switch (Type) { 369 case wasm::WASM_NAMES_FUNCTION: { 370 uint32_t Count = readVaruint32(Ctx); 371 while (Count--) { 372 uint32_t Index = readVaruint32(Ctx); 373 if (!Seen.insert(Index).second) 374 return make_error<GenericBinaryError>("Function named more than once", 375 object_error::parse_failed); 376 StringRef Name = readString(Ctx); 377 if (!isValidFunctionIndex(Index) || Name.empty()) 378 return make_error<GenericBinaryError>("Invalid name entry", 379 object_error::parse_failed); 380 DebugNames.push_back(wasm::WasmFunctionName{Index, Name}); 381 if (isDefinedFunctionIndex(Index)) 382 getDefinedFunction(Index).DebugName = Name; 383 } 384 break; 385 } 386 // Ignore local names for now 387 case wasm::WASM_NAMES_LOCAL: 388 default: 389 Ctx.Ptr += Size; 390 break; 391 } 392 if (Ctx.Ptr != SubSectionEnd) 393 return make_error<GenericBinaryError>( 394 "Name sub-section ended prematurely", object_error::parse_failed); 395 } 396 397 if (Ctx.Ptr != Ctx.End) 398 return make_error<GenericBinaryError>("Name section ended prematurely", 399 object_error::parse_failed); 400 return Error::success(); 401 } 402 403 Error WasmObjectFile::parseLinkingSection(ReadContext &Ctx) { 404 HasLinkingSection = true; 405 if (FunctionTypes.size() && !SeenCodeSection) { 406 return make_error<GenericBinaryError>( 407 "Linking data must come after code section", 408 object_error::parse_failed); 409 } 410 411 LinkingData.Version = readVaruint32(Ctx); 412 if (LinkingData.Version != wasm::WasmMetadataVersion) { 413 return make_error<GenericBinaryError>( 414 "Unexpected metadata version: " + Twine(LinkingData.Version) + 415 " (Expected: " + Twine(wasm::WasmMetadataVersion) + ")", 416 object_error::parse_failed); 417 } 418 419 const uint8_t *OrigEnd = Ctx.End; 420 while (Ctx.Ptr < OrigEnd) { 421 Ctx.End = OrigEnd; 422 uint8_t Type = readUint8(Ctx); 423 uint32_t Size = readVaruint32(Ctx); 424 LLVM_DEBUG(dbgs() << "readSubsection type=" << int(Type) << " size=" << Size 425 << "\n"); 426 Ctx.End = Ctx.Ptr + Size; 427 switch (Type) { 428 case wasm::WASM_SYMBOL_TABLE: 429 if (Error Err = parseLinkingSectionSymtab(Ctx)) 430 return Err; 431 break; 432 case wasm::WASM_SEGMENT_INFO: { 433 uint32_t Count = readVaruint32(Ctx); 434 if (Count > DataSegments.size()) 435 return make_error<GenericBinaryError>("Too many segment names", 436 object_error::parse_failed); 437 for (uint32_t I = 0; I < Count; I++) { 438 DataSegments[I].Data.Name = readString(Ctx); 439 DataSegments[I].Data.Alignment = readVaruint32(Ctx); 440 DataSegments[I].Data.LinkerFlags = readVaruint32(Ctx); 441 } 442 break; 443 } 444 case wasm::WASM_INIT_FUNCS: { 445 uint32_t Count = readVaruint32(Ctx); 446 LinkingData.InitFunctions.reserve(Count); 447 for (uint32_t I = 0; I < Count; I++) { 448 wasm::WasmInitFunc Init; 449 Init.Priority = readVaruint32(Ctx); 450 Init.Symbol = readVaruint32(Ctx); 451 if (!isValidFunctionSymbol(Init.Symbol)) 452 return make_error<GenericBinaryError>("Invalid function symbol: " + 453 Twine(Init.Symbol), 454 object_error::parse_failed); 455 LinkingData.InitFunctions.emplace_back(Init); 456 } 457 break; 458 } 459 case wasm::WASM_COMDAT_INFO: 460 if (Error Err = parseLinkingSectionComdat(Ctx)) 461 return Err; 462 break; 463 default: 464 Ctx.Ptr += Size; 465 break; 466 } 467 if (Ctx.Ptr != Ctx.End) 468 return make_error<GenericBinaryError>( 469 "Linking sub-section ended prematurely", object_error::parse_failed); 470 } 471 if (Ctx.Ptr != OrigEnd) 472 return make_error<GenericBinaryError>("Linking section ended prematurely", 473 object_error::parse_failed); 474 return Error::success(); 475 } 476 477 Error WasmObjectFile::parseLinkingSectionSymtab(ReadContext &Ctx) { 478 uint32_t Count = readVaruint32(Ctx); 479 LinkingData.SymbolTable.reserve(Count); 480 Symbols.reserve(Count); 481 StringSet<> SymbolNames; 482 483 std::vector<wasm::WasmImport *> ImportedGlobals; 484 std::vector<wasm::WasmImport *> ImportedFunctions; 485 std::vector<wasm::WasmImport *> ImportedEvents; 486 ImportedGlobals.reserve(Imports.size()); 487 ImportedFunctions.reserve(Imports.size()); 488 ImportedEvents.reserve(Imports.size()); 489 for (auto &I : Imports) { 490 if (I.Kind == wasm::WASM_EXTERNAL_FUNCTION) 491 ImportedFunctions.emplace_back(&I); 492 else if (I.Kind == wasm::WASM_EXTERNAL_GLOBAL) 493 ImportedGlobals.emplace_back(&I); 494 else if (I.Kind == wasm::WASM_EXTERNAL_EVENT) 495 ImportedEvents.emplace_back(&I); 496 } 497 498 while (Count--) { 499 wasm::WasmSymbolInfo Info; 500 const wasm::WasmSignature *Signature = nullptr; 501 const wasm::WasmGlobalType *GlobalType = nullptr; 502 const wasm::WasmEventType *EventType = nullptr; 503 504 Info.Kind = readUint8(Ctx); 505 Info.Flags = readVaruint32(Ctx); 506 bool IsDefined = (Info.Flags & wasm::WASM_SYMBOL_UNDEFINED) == 0; 507 508 switch (Info.Kind) { 509 case wasm::WASM_SYMBOL_TYPE_FUNCTION: 510 Info.ElementIndex = readVaruint32(Ctx); 511 if (!isValidFunctionIndex(Info.ElementIndex) || 512 IsDefined != isDefinedFunctionIndex(Info.ElementIndex)) 513 return make_error<GenericBinaryError>("invalid function symbol index", 514 object_error::parse_failed); 515 if (IsDefined) { 516 Info.Name = readString(Ctx); 517 unsigned FuncIndex = Info.ElementIndex - NumImportedFunctions; 518 Signature = &Signatures[FunctionTypes[FuncIndex]]; 519 wasm::WasmFunction &Function = Functions[FuncIndex]; 520 if (Function.SymbolName.empty()) 521 Function.SymbolName = Info.Name; 522 } else { 523 wasm::WasmImport &Import = *ImportedFunctions[Info.ElementIndex]; 524 if ((Info.Flags & wasm::WASM_SYMBOL_EXPLICIT_NAME) != 0) { 525 Info.Name = readString(Ctx); 526 Info.ImportName = Import.Field; 527 } else { 528 Info.Name = Import.Field; 529 } 530 Signature = &Signatures[Import.SigIndex]; 531 if (!Import.Module.empty()) { 532 Info.ImportModule = Import.Module; 533 } 534 } 535 break; 536 537 case wasm::WASM_SYMBOL_TYPE_GLOBAL: 538 Info.ElementIndex = readVaruint32(Ctx); 539 if (!isValidGlobalIndex(Info.ElementIndex) || 540 IsDefined != isDefinedGlobalIndex(Info.ElementIndex)) 541 return make_error<GenericBinaryError>("invalid global symbol index", 542 object_error::parse_failed); 543 if (!IsDefined && (Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) == 544 wasm::WASM_SYMBOL_BINDING_WEAK) 545 return make_error<GenericBinaryError>("undefined weak global symbol", 546 object_error::parse_failed); 547 if (IsDefined) { 548 Info.Name = readString(Ctx); 549 unsigned GlobalIndex = Info.ElementIndex - NumImportedGlobals; 550 wasm::WasmGlobal &Global = Globals[GlobalIndex]; 551 GlobalType = &Global.Type; 552 if (Global.SymbolName.empty()) 553 Global.SymbolName = Info.Name; 554 } else { 555 wasm::WasmImport &Import = *ImportedGlobals[Info.ElementIndex]; 556 if ((Info.Flags & wasm::WASM_SYMBOL_EXPLICIT_NAME) != 0) { 557 Info.Name = readString(Ctx); 558 Info.ImportName = Import.Field; 559 } else { 560 Info.Name = Import.Field; 561 } 562 GlobalType = &Import.Global; 563 Info.ImportName = Import.Field; 564 if (!Import.Module.empty()) { 565 Info.ImportModule = Import.Module; 566 } 567 } 568 break; 569 570 case wasm::WASM_SYMBOL_TYPE_DATA: 571 Info.Name = readString(Ctx); 572 if (IsDefined) { 573 auto Index = readVaruint32(Ctx); 574 if (Index >= DataSegments.size()) 575 return make_error<GenericBinaryError>("invalid data symbol index", 576 object_error::parse_failed); 577 auto Offset = readVaruint64(Ctx); 578 auto Size = readVaruint64(Ctx); 579 if (Offset + Size > DataSegments[Index].Data.Content.size()) 580 return make_error<GenericBinaryError>("invalid data symbol offset", 581 object_error::parse_failed); 582 Info.DataRef = wasm::WasmDataReference{Index, Offset, Size}; 583 } 584 break; 585 586 case wasm::WASM_SYMBOL_TYPE_SECTION: { 587 if ((Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) != 588 wasm::WASM_SYMBOL_BINDING_LOCAL) 589 return make_error<GenericBinaryError>( 590 "Section symbols must have local binding", 591 object_error::parse_failed); 592 Info.ElementIndex = readVaruint32(Ctx); 593 // Use somewhat unique section name as symbol name. 594 StringRef SectionName = Sections[Info.ElementIndex].Name; 595 Info.Name = SectionName; 596 break; 597 } 598 599 case wasm::WASM_SYMBOL_TYPE_EVENT: { 600 Info.ElementIndex = readVaruint32(Ctx); 601 if (!isValidEventIndex(Info.ElementIndex) || 602 IsDefined != isDefinedEventIndex(Info.ElementIndex)) 603 return make_error<GenericBinaryError>("invalid event symbol index", 604 object_error::parse_failed); 605 if (!IsDefined && (Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) == 606 wasm::WASM_SYMBOL_BINDING_WEAK) 607 return make_error<GenericBinaryError>("undefined weak global symbol", 608 object_error::parse_failed); 609 if (IsDefined) { 610 Info.Name = readString(Ctx); 611 unsigned EventIndex = Info.ElementIndex - NumImportedEvents; 612 wasm::WasmEvent &Event = Events[EventIndex]; 613 Signature = &Signatures[Event.Type.SigIndex]; 614 EventType = &Event.Type; 615 if (Event.SymbolName.empty()) 616 Event.SymbolName = Info.Name; 617 618 } else { 619 wasm::WasmImport &Import = *ImportedEvents[Info.ElementIndex]; 620 if ((Info.Flags & wasm::WASM_SYMBOL_EXPLICIT_NAME) != 0) { 621 Info.Name = readString(Ctx); 622 Info.ImportName = Import.Field; 623 } else { 624 Info.Name = Import.Field; 625 } 626 EventType = &Import.Event; 627 Signature = &Signatures[EventType->SigIndex]; 628 if (!Import.Module.empty()) { 629 Info.ImportModule = Import.Module; 630 } 631 } 632 break; 633 } 634 635 default: 636 return make_error<GenericBinaryError>("Invalid symbol type", 637 object_error::parse_failed); 638 } 639 640 if ((Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK) != 641 wasm::WASM_SYMBOL_BINDING_LOCAL && 642 !SymbolNames.insert(Info.Name).second) 643 return make_error<GenericBinaryError>("Duplicate symbol name " + 644 Twine(Info.Name), 645 object_error::parse_failed); 646 LinkingData.SymbolTable.emplace_back(Info); 647 Symbols.emplace_back(LinkingData.SymbolTable.back(), GlobalType, EventType, 648 Signature); 649 LLVM_DEBUG(dbgs() << "Adding symbol: " << Symbols.back() << "\n"); 650 } 651 652 return Error::success(); 653 } 654 655 Error WasmObjectFile::parseLinkingSectionComdat(ReadContext &Ctx) { 656 uint32_t ComdatCount = readVaruint32(Ctx); 657 StringSet<> ComdatSet; 658 for (unsigned ComdatIndex = 0; ComdatIndex < ComdatCount; ++ComdatIndex) { 659 StringRef Name = readString(Ctx); 660 if (Name.empty() || !ComdatSet.insert(Name).second) 661 return make_error<GenericBinaryError>("Bad/duplicate COMDAT name " + 662 Twine(Name), 663 object_error::parse_failed); 664 LinkingData.Comdats.emplace_back(Name); 665 uint32_t Flags = readVaruint32(Ctx); 666 if (Flags != 0) 667 return make_error<GenericBinaryError>("Unsupported COMDAT flags", 668 object_error::parse_failed); 669 670 uint32_t EntryCount = readVaruint32(Ctx); 671 while (EntryCount--) { 672 unsigned Kind = readVaruint32(Ctx); 673 unsigned Index = readVaruint32(Ctx); 674 switch (Kind) { 675 default: 676 return make_error<GenericBinaryError>("Invalid COMDAT entry type", 677 object_error::parse_failed); 678 case wasm::WASM_COMDAT_DATA: 679 if (Index >= DataSegments.size()) 680 return make_error<GenericBinaryError>( 681 "COMDAT data index out of range", object_error::parse_failed); 682 if (DataSegments[Index].Data.Comdat != UINT32_MAX) 683 return make_error<GenericBinaryError>("Data segment in two COMDATs", 684 object_error::parse_failed); 685 DataSegments[Index].Data.Comdat = ComdatIndex; 686 break; 687 case wasm::WASM_COMDAT_FUNCTION: 688 if (!isDefinedFunctionIndex(Index)) 689 return make_error<GenericBinaryError>( 690 "COMDAT function index out of range", object_error::parse_failed); 691 if (getDefinedFunction(Index).Comdat != UINT32_MAX) 692 return make_error<GenericBinaryError>("Function in two COMDATs", 693 object_error::parse_failed); 694 getDefinedFunction(Index).Comdat = ComdatIndex; 695 break; 696 } 697 } 698 } 699 return Error::success(); 700 } 701 702 Error WasmObjectFile::parseProducersSection(ReadContext &Ctx) { 703 llvm::SmallSet<StringRef, 3> FieldsSeen; 704 uint32_t Fields = readVaruint32(Ctx); 705 for (size_t I = 0; I < Fields; ++I) { 706 StringRef FieldName = readString(Ctx); 707 if (!FieldsSeen.insert(FieldName).second) 708 return make_error<GenericBinaryError>( 709 "Producers section does not have unique fields", 710 object_error::parse_failed); 711 std::vector<std::pair<std::string, std::string>> *ProducerVec = nullptr; 712 if (FieldName == "language") { 713 ProducerVec = &ProducerInfo.Languages; 714 } else if (FieldName == "processed-by") { 715 ProducerVec = &ProducerInfo.Tools; 716 } else if (FieldName == "sdk") { 717 ProducerVec = &ProducerInfo.SDKs; 718 } else { 719 return make_error<GenericBinaryError>( 720 "Producers section field is not named one of language, processed-by, " 721 "or sdk", 722 object_error::parse_failed); 723 } 724 uint32_t ValueCount = readVaruint32(Ctx); 725 llvm::SmallSet<StringRef, 8> ProducersSeen; 726 for (size_t J = 0; J < ValueCount; ++J) { 727 StringRef Name = readString(Ctx); 728 StringRef Version = readString(Ctx); 729 if (!ProducersSeen.insert(Name).second) { 730 return make_error<GenericBinaryError>( 731 "Producers section contains repeated producer", 732 object_error::parse_failed); 733 } 734 ProducerVec->emplace_back(std::string(Name), std::string(Version)); 735 } 736 } 737 if (Ctx.Ptr != Ctx.End) 738 return make_error<GenericBinaryError>("Producers section ended prematurely", 739 object_error::parse_failed); 740 return Error::success(); 741 } 742 743 Error WasmObjectFile::parseTargetFeaturesSection(ReadContext &Ctx) { 744 llvm::SmallSet<std::string, 8> FeaturesSeen; 745 uint32_t FeatureCount = readVaruint32(Ctx); 746 for (size_t I = 0; I < FeatureCount; ++I) { 747 wasm::WasmFeatureEntry Feature; 748 Feature.Prefix = readUint8(Ctx); 749 switch (Feature.Prefix) { 750 case wasm::WASM_FEATURE_PREFIX_USED: 751 case wasm::WASM_FEATURE_PREFIX_REQUIRED: 752 case wasm::WASM_FEATURE_PREFIX_DISALLOWED: 753 break; 754 default: 755 return make_error<GenericBinaryError>("Unknown feature policy prefix", 756 object_error::parse_failed); 757 } 758 Feature.Name = std::string(readString(Ctx)); 759 if (!FeaturesSeen.insert(Feature.Name).second) 760 return make_error<GenericBinaryError>( 761 "Target features section contains repeated feature \"" + 762 Feature.Name + "\"", 763 object_error::parse_failed); 764 TargetFeatures.push_back(Feature); 765 } 766 if (Ctx.Ptr != Ctx.End) 767 return make_error<GenericBinaryError>( 768 "Target features section ended prematurely", 769 object_error::parse_failed); 770 return Error::success(); 771 } 772 773 Error WasmObjectFile::parseRelocSection(StringRef Name, ReadContext &Ctx) { 774 uint32_t SectionIndex = readVaruint32(Ctx); 775 if (SectionIndex >= Sections.size()) 776 return make_error<GenericBinaryError>("Invalid section index", 777 object_error::parse_failed); 778 WasmSection &Section = Sections[SectionIndex]; 779 uint32_t RelocCount = readVaruint32(Ctx); 780 uint32_t EndOffset = Section.Content.size(); 781 uint32_t PreviousOffset = 0; 782 while (RelocCount--) { 783 wasm::WasmRelocation Reloc = {}; 784 Reloc.Type = readVaruint32(Ctx); 785 Reloc.Offset = readVaruint32(Ctx); 786 if (Reloc.Offset < PreviousOffset) 787 return make_error<GenericBinaryError>("Relocations not in offset order", 788 object_error::parse_failed); 789 PreviousOffset = Reloc.Offset; 790 Reloc.Index = readVaruint32(Ctx); 791 switch (Reloc.Type) { 792 case wasm::R_WASM_FUNCTION_INDEX_LEB: 793 case wasm::R_WASM_TABLE_INDEX_SLEB: 794 case wasm::R_WASM_TABLE_INDEX_I32: 795 case wasm::R_WASM_TABLE_INDEX_REL_SLEB: 796 if (!isValidFunctionSymbol(Reloc.Index)) 797 return make_error<GenericBinaryError>("Bad relocation function index", 798 object_error::parse_failed); 799 break; 800 case wasm::R_WASM_TYPE_INDEX_LEB: 801 if (Reloc.Index >= Signatures.size()) 802 return make_error<GenericBinaryError>("Bad relocation type index", 803 object_error::parse_failed); 804 break; 805 case wasm::R_WASM_GLOBAL_INDEX_LEB: 806 // R_WASM_GLOBAL_INDEX_LEB are can be used against function and data 807 // symbols to refer to their GOT entries. 808 if (!isValidGlobalSymbol(Reloc.Index) && 809 !isValidDataSymbol(Reloc.Index) && 810 !isValidFunctionSymbol(Reloc.Index)) 811 return make_error<GenericBinaryError>("Bad relocation global index", 812 object_error::parse_failed); 813 break; 814 case wasm::R_WASM_GLOBAL_INDEX_I32: 815 if (!isValidGlobalSymbol(Reloc.Index)) 816 return make_error<GenericBinaryError>("Bad relocation global index", 817 object_error::parse_failed); 818 break; 819 case wasm::R_WASM_EVENT_INDEX_LEB: 820 if (!isValidEventSymbol(Reloc.Index)) 821 return make_error<GenericBinaryError>("Bad relocation event index", 822 object_error::parse_failed); 823 break; 824 case wasm::R_WASM_MEMORY_ADDR_LEB: 825 case wasm::R_WASM_MEMORY_ADDR_SLEB: 826 case wasm::R_WASM_MEMORY_ADDR_I32: 827 case wasm::R_WASM_MEMORY_ADDR_REL_SLEB: 828 if (!isValidDataSymbol(Reloc.Index)) 829 return make_error<GenericBinaryError>("Bad relocation data index", 830 object_error::parse_failed); 831 Reloc.Addend = readVarint32(Ctx); 832 break; 833 case wasm::R_WASM_MEMORY_ADDR_LEB64: 834 case wasm::R_WASM_MEMORY_ADDR_SLEB64: 835 case wasm::R_WASM_MEMORY_ADDR_I64: 836 case wasm::R_WASM_MEMORY_ADDR_REL_SLEB64: 837 if (!isValidDataSymbol(Reloc.Index)) 838 return make_error<GenericBinaryError>("Bad relocation data index", 839 object_error::parse_failed); 840 Reloc.Addend = readVarint64(Ctx); 841 break; 842 case wasm::R_WASM_FUNCTION_OFFSET_I32: 843 if (!isValidFunctionSymbol(Reloc.Index)) 844 return make_error<GenericBinaryError>("Bad relocation function index", 845 object_error::parse_failed); 846 Reloc.Addend = readVarint32(Ctx); 847 break; 848 case wasm::R_WASM_SECTION_OFFSET_I32: 849 if (!isValidSectionSymbol(Reloc.Index)) 850 return make_error<GenericBinaryError>("Bad relocation section index", 851 object_error::parse_failed); 852 Reloc.Addend = readVarint32(Ctx); 853 break; 854 default: 855 return make_error<GenericBinaryError>("Bad relocation type: " + 856 Twine(Reloc.Type), 857 object_error::parse_failed); 858 } 859 860 // Relocations must fit inside the section, and must appear in order. They 861 // also shouldn't overlap a function/element boundary, but we don't bother 862 // to check that. 863 uint64_t Size = 5; 864 if (Reloc.Type == wasm::R_WASM_MEMORY_ADDR_LEB64 || 865 Reloc.Type == wasm::R_WASM_MEMORY_ADDR_SLEB64 || 866 Reloc.Type == wasm::R_WASM_MEMORY_ADDR_REL_SLEB64) 867 Size = 10; 868 if (Reloc.Type == wasm::R_WASM_TABLE_INDEX_I32 || 869 Reloc.Type == wasm::R_WASM_MEMORY_ADDR_I32 || 870 Reloc.Type == wasm::R_WASM_SECTION_OFFSET_I32 || 871 Reloc.Type == wasm::R_WASM_FUNCTION_OFFSET_I32 || 872 Reloc.Type == wasm::R_WASM_GLOBAL_INDEX_I32) 873 Size = 4; 874 if (Reloc.Type == wasm::R_WASM_MEMORY_ADDR_I64) 875 Size = 8; 876 if (Reloc.Offset + Size > EndOffset) 877 return make_error<GenericBinaryError>("Bad relocation offset", 878 object_error::parse_failed); 879 880 Section.Relocations.push_back(Reloc); 881 } 882 if (Ctx.Ptr != Ctx.End) 883 return make_error<GenericBinaryError>("Reloc section ended prematurely", 884 object_error::parse_failed); 885 return Error::success(); 886 } 887 888 Error WasmObjectFile::parseCustomSection(WasmSection &Sec, ReadContext &Ctx) { 889 if (Sec.Name == "dylink") { 890 if (Error Err = parseDylinkSection(Ctx)) 891 return Err; 892 } else if (Sec.Name == "name") { 893 if (Error Err = parseNameSection(Ctx)) 894 return Err; 895 } else if (Sec.Name == "linking") { 896 if (Error Err = parseLinkingSection(Ctx)) 897 return Err; 898 } else if (Sec.Name == "producers") { 899 if (Error Err = parseProducersSection(Ctx)) 900 return Err; 901 } else if (Sec.Name == "target_features") { 902 if (Error Err = parseTargetFeaturesSection(Ctx)) 903 return Err; 904 } else if (Sec.Name.startswith("reloc.")) { 905 if (Error Err = parseRelocSection(Sec.Name, Ctx)) 906 return Err; 907 } 908 return Error::success(); 909 } 910 911 Error WasmObjectFile::parseTypeSection(ReadContext &Ctx) { 912 uint32_t Count = readVaruint32(Ctx); 913 Signatures.reserve(Count); 914 while (Count--) { 915 wasm::WasmSignature Sig; 916 uint8_t Form = readUint8(Ctx); 917 if (Form != wasm::WASM_TYPE_FUNC) { 918 return make_error<GenericBinaryError>("Invalid signature type", 919 object_error::parse_failed); 920 } 921 uint32_t ParamCount = readVaruint32(Ctx); 922 Sig.Params.reserve(ParamCount); 923 while (ParamCount--) { 924 uint32_t ParamType = readUint8(Ctx); 925 Sig.Params.push_back(wasm::ValType(ParamType)); 926 } 927 uint32_t ReturnCount = readVaruint32(Ctx); 928 while (ReturnCount--) { 929 uint32_t ReturnType = readUint8(Ctx); 930 Sig.Returns.push_back(wasm::ValType(ReturnType)); 931 } 932 Signatures.push_back(std::move(Sig)); 933 } 934 if (Ctx.Ptr != Ctx.End) 935 return make_error<GenericBinaryError>("Type section ended prematurely", 936 object_error::parse_failed); 937 return Error::success(); 938 } 939 940 Error WasmObjectFile::parseImportSection(ReadContext &Ctx) { 941 uint32_t Count = readVaruint32(Ctx); 942 Imports.reserve(Count); 943 for (uint32_t I = 0; I < Count; I++) { 944 wasm::WasmImport Im; 945 Im.Module = readString(Ctx); 946 Im.Field = readString(Ctx); 947 Im.Kind = readUint8(Ctx); 948 switch (Im.Kind) { 949 case wasm::WASM_EXTERNAL_FUNCTION: 950 NumImportedFunctions++; 951 Im.SigIndex = readVaruint32(Ctx); 952 break; 953 case wasm::WASM_EXTERNAL_GLOBAL: 954 NumImportedGlobals++; 955 Im.Global.Type = readUint8(Ctx); 956 Im.Global.Mutable = readVaruint1(Ctx); 957 break; 958 case wasm::WASM_EXTERNAL_MEMORY: 959 Im.Memory = readLimits(Ctx); 960 break; 961 case wasm::WASM_EXTERNAL_TABLE: 962 Im.Table = readTable(Ctx); 963 if (Im.Table.ElemType != wasm::WASM_TYPE_FUNCREF) 964 return make_error<GenericBinaryError>("Invalid table element type", 965 object_error::parse_failed); 966 break; 967 case wasm::WASM_EXTERNAL_EVENT: 968 NumImportedEvents++; 969 Im.Event.Attribute = readVarint32(Ctx); 970 Im.Event.SigIndex = readVarint32(Ctx); 971 break; 972 default: 973 return make_error<GenericBinaryError>("Unexpected import kind", 974 object_error::parse_failed); 975 } 976 Imports.push_back(Im); 977 } 978 if (Ctx.Ptr != Ctx.End) 979 return make_error<GenericBinaryError>("Import section ended prematurely", 980 object_error::parse_failed); 981 return Error::success(); 982 } 983 984 Error WasmObjectFile::parseFunctionSection(ReadContext &Ctx) { 985 uint32_t Count = readVaruint32(Ctx); 986 FunctionTypes.reserve(Count); 987 Functions.resize(Count); 988 uint32_t NumTypes = Signatures.size(); 989 while (Count--) { 990 uint32_t Type = readVaruint32(Ctx); 991 if (Type >= NumTypes) 992 return make_error<GenericBinaryError>("Invalid function type", 993 object_error::parse_failed); 994 FunctionTypes.push_back(Type); 995 } 996 if (Ctx.Ptr != Ctx.End) 997 return make_error<GenericBinaryError>("Function section ended prematurely", 998 object_error::parse_failed); 999 return Error::success(); 1000 } 1001 1002 Error WasmObjectFile::parseTableSection(ReadContext &Ctx) { 1003 uint32_t Count = readVaruint32(Ctx); 1004 Tables.reserve(Count); 1005 while (Count--) { 1006 Tables.push_back(readTable(Ctx)); 1007 if (Tables.back().ElemType != wasm::WASM_TYPE_FUNCREF) { 1008 return make_error<GenericBinaryError>("Invalid table element type", 1009 object_error::parse_failed); 1010 } 1011 } 1012 if (Ctx.Ptr != Ctx.End) 1013 return make_error<GenericBinaryError>("Table section ended prematurely", 1014 object_error::parse_failed); 1015 return Error::success(); 1016 } 1017 1018 Error WasmObjectFile::parseMemorySection(ReadContext &Ctx) { 1019 uint32_t Count = readVaruint32(Ctx); 1020 Memories.reserve(Count); 1021 while (Count--) { 1022 Memories.push_back(readLimits(Ctx)); 1023 } 1024 if (Ctx.Ptr != Ctx.End) 1025 return make_error<GenericBinaryError>("Memory section ended prematurely", 1026 object_error::parse_failed); 1027 return Error::success(); 1028 } 1029 1030 Error WasmObjectFile::parseEventSection(ReadContext &Ctx) { 1031 EventSection = Sections.size(); 1032 uint32_t Count = readVarint32(Ctx); 1033 Events.reserve(Count); 1034 while (Count--) { 1035 wasm::WasmEvent Event; 1036 Event.Index = NumImportedEvents + Events.size(); 1037 Event.Type.Attribute = readVaruint32(Ctx); 1038 Event.Type.SigIndex = readVarint32(Ctx); 1039 Events.push_back(Event); 1040 } 1041 1042 if (Ctx.Ptr != Ctx.End) 1043 return make_error<GenericBinaryError>("Event section ended prematurely", 1044 object_error::parse_failed); 1045 return Error::success(); 1046 } 1047 1048 Error WasmObjectFile::parseGlobalSection(ReadContext &Ctx) { 1049 GlobalSection = Sections.size(); 1050 uint32_t Count = readVaruint32(Ctx); 1051 Globals.reserve(Count); 1052 while (Count--) { 1053 wasm::WasmGlobal Global; 1054 Global.Index = NumImportedGlobals + Globals.size(); 1055 Global.Type.Type = readUint8(Ctx); 1056 Global.Type.Mutable = readVaruint1(Ctx); 1057 if (Error Err = readInitExpr(Global.InitExpr, Ctx)) 1058 return Err; 1059 Globals.push_back(Global); 1060 } 1061 if (Ctx.Ptr != Ctx.End) 1062 return make_error<GenericBinaryError>("Global section ended prematurely", 1063 object_error::parse_failed); 1064 return Error::success(); 1065 } 1066 1067 Error WasmObjectFile::parseExportSection(ReadContext &Ctx) { 1068 uint32_t Count = readVaruint32(Ctx); 1069 Exports.reserve(Count); 1070 for (uint32_t I = 0; I < Count; I++) { 1071 wasm::WasmExport Ex; 1072 Ex.Name = readString(Ctx); 1073 Ex.Kind = readUint8(Ctx); 1074 Ex.Index = readVaruint32(Ctx); 1075 switch (Ex.Kind) { 1076 case wasm::WASM_EXTERNAL_FUNCTION: 1077 1078 if (!isDefinedFunctionIndex(Ex.Index)) 1079 return make_error<GenericBinaryError>("Invalid function export", 1080 object_error::parse_failed); 1081 getDefinedFunction(Ex.Index).ExportName = Ex.Name; 1082 break; 1083 case wasm::WASM_EXTERNAL_GLOBAL: 1084 if (!isValidGlobalIndex(Ex.Index)) 1085 return make_error<GenericBinaryError>("Invalid global export", 1086 object_error::parse_failed); 1087 break; 1088 case wasm::WASM_EXTERNAL_EVENT: 1089 if (!isValidEventIndex(Ex.Index)) 1090 return make_error<GenericBinaryError>("Invalid event export", 1091 object_error::parse_failed); 1092 break; 1093 case wasm::WASM_EXTERNAL_MEMORY: 1094 case wasm::WASM_EXTERNAL_TABLE: 1095 break; 1096 default: 1097 return make_error<GenericBinaryError>("Unexpected export kind", 1098 object_error::parse_failed); 1099 } 1100 Exports.push_back(Ex); 1101 } 1102 if (Ctx.Ptr != Ctx.End) 1103 return make_error<GenericBinaryError>("Export section ended prematurely", 1104 object_error::parse_failed); 1105 return Error::success(); 1106 } 1107 1108 bool WasmObjectFile::isValidFunctionIndex(uint32_t Index) const { 1109 return Index < NumImportedFunctions + FunctionTypes.size(); 1110 } 1111 1112 bool WasmObjectFile::isDefinedFunctionIndex(uint32_t Index) const { 1113 return Index >= NumImportedFunctions && isValidFunctionIndex(Index); 1114 } 1115 1116 bool WasmObjectFile::isValidGlobalIndex(uint32_t Index) const { 1117 return Index < NumImportedGlobals + Globals.size(); 1118 } 1119 1120 bool WasmObjectFile::isDefinedGlobalIndex(uint32_t Index) const { 1121 return Index >= NumImportedGlobals && isValidGlobalIndex(Index); 1122 } 1123 1124 bool WasmObjectFile::isValidEventIndex(uint32_t Index) const { 1125 return Index < NumImportedEvents + Events.size(); 1126 } 1127 1128 bool WasmObjectFile::isDefinedEventIndex(uint32_t Index) const { 1129 return Index >= NumImportedEvents && isValidEventIndex(Index); 1130 } 1131 1132 bool WasmObjectFile::isValidFunctionSymbol(uint32_t Index) const { 1133 return Index < Symbols.size() && Symbols[Index].isTypeFunction(); 1134 } 1135 1136 bool WasmObjectFile::isValidGlobalSymbol(uint32_t Index) const { 1137 return Index < Symbols.size() && Symbols[Index].isTypeGlobal(); 1138 } 1139 1140 bool WasmObjectFile::isValidEventSymbol(uint32_t Index) const { 1141 return Index < Symbols.size() && Symbols[Index].isTypeEvent(); 1142 } 1143 1144 bool WasmObjectFile::isValidDataSymbol(uint32_t Index) const { 1145 return Index < Symbols.size() && Symbols[Index].isTypeData(); 1146 } 1147 1148 bool WasmObjectFile::isValidSectionSymbol(uint32_t Index) const { 1149 return Index < Symbols.size() && Symbols[Index].isTypeSection(); 1150 } 1151 1152 wasm::WasmFunction &WasmObjectFile::getDefinedFunction(uint32_t Index) { 1153 assert(isDefinedFunctionIndex(Index)); 1154 return Functions[Index - NumImportedFunctions]; 1155 } 1156 1157 const wasm::WasmFunction & 1158 WasmObjectFile::getDefinedFunction(uint32_t Index) const { 1159 assert(isDefinedFunctionIndex(Index)); 1160 return Functions[Index - NumImportedFunctions]; 1161 } 1162 1163 wasm::WasmGlobal &WasmObjectFile::getDefinedGlobal(uint32_t Index) { 1164 assert(isDefinedGlobalIndex(Index)); 1165 return Globals[Index - NumImportedGlobals]; 1166 } 1167 1168 wasm::WasmEvent &WasmObjectFile::getDefinedEvent(uint32_t Index) { 1169 assert(isDefinedEventIndex(Index)); 1170 return Events[Index - NumImportedEvents]; 1171 } 1172 1173 Error WasmObjectFile::parseStartSection(ReadContext &Ctx) { 1174 StartFunction = readVaruint32(Ctx); 1175 if (!isValidFunctionIndex(StartFunction)) 1176 return make_error<GenericBinaryError>("Invalid start function", 1177 object_error::parse_failed); 1178 return Error::success(); 1179 } 1180 1181 Error WasmObjectFile::parseCodeSection(ReadContext &Ctx) { 1182 SeenCodeSection = true; 1183 CodeSection = Sections.size(); 1184 uint32_t FunctionCount = readVaruint32(Ctx); 1185 if (FunctionCount != FunctionTypes.size()) { 1186 return make_error<GenericBinaryError>("Invalid function count", 1187 object_error::parse_failed); 1188 } 1189 1190 for (uint32_t i = 0; i < FunctionCount; i++) { 1191 wasm::WasmFunction& Function = Functions[i]; 1192 const uint8_t *FunctionStart = Ctx.Ptr; 1193 uint32_t Size = readVaruint32(Ctx); 1194 const uint8_t *FunctionEnd = Ctx.Ptr + Size; 1195 1196 Function.CodeOffset = Ctx.Ptr - FunctionStart; 1197 Function.Index = NumImportedFunctions + i; 1198 Function.CodeSectionOffset = FunctionStart - Ctx.Start; 1199 Function.Size = FunctionEnd - FunctionStart; 1200 1201 uint32_t NumLocalDecls = readVaruint32(Ctx); 1202 Function.Locals.reserve(NumLocalDecls); 1203 while (NumLocalDecls--) { 1204 wasm::WasmLocalDecl Decl; 1205 Decl.Count = readVaruint32(Ctx); 1206 Decl.Type = readUint8(Ctx); 1207 Function.Locals.push_back(Decl); 1208 } 1209 1210 uint32_t BodySize = FunctionEnd - Ctx.Ptr; 1211 Function.Body = ArrayRef<uint8_t>(Ctx.Ptr, BodySize); 1212 // This will be set later when reading in the linking metadata section. 1213 Function.Comdat = UINT32_MAX; 1214 Ctx.Ptr += BodySize; 1215 assert(Ctx.Ptr == FunctionEnd); 1216 } 1217 if (Ctx.Ptr != Ctx.End) 1218 return make_error<GenericBinaryError>("Code section ended prematurely", 1219 object_error::parse_failed); 1220 return Error::success(); 1221 } 1222 1223 Error WasmObjectFile::parseElemSection(ReadContext &Ctx) { 1224 uint32_t Count = readVaruint32(Ctx); 1225 ElemSegments.reserve(Count); 1226 while (Count--) { 1227 wasm::WasmElemSegment Segment; 1228 Segment.TableIndex = readVaruint32(Ctx); 1229 if (Segment.TableIndex != 0) { 1230 return make_error<GenericBinaryError>("Invalid TableIndex", 1231 object_error::parse_failed); 1232 } 1233 if (Error Err = readInitExpr(Segment.Offset, Ctx)) 1234 return Err; 1235 uint32_t NumElems = readVaruint32(Ctx); 1236 while (NumElems--) { 1237 Segment.Functions.push_back(readVaruint32(Ctx)); 1238 } 1239 ElemSegments.push_back(Segment); 1240 } 1241 if (Ctx.Ptr != Ctx.End) 1242 return make_error<GenericBinaryError>("Elem section ended prematurely", 1243 object_error::parse_failed); 1244 return Error::success(); 1245 } 1246 1247 Error WasmObjectFile::parseDataSection(ReadContext &Ctx) { 1248 DataSection = Sections.size(); 1249 uint32_t Count = readVaruint32(Ctx); 1250 if (DataCount && Count != DataCount.getValue()) 1251 return make_error<GenericBinaryError>( 1252 "Number of data segments does not match DataCount section"); 1253 DataSegments.reserve(Count); 1254 while (Count--) { 1255 WasmSegment Segment; 1256 Segment.Data.InitFlags = readVaruint32(Ctx); 1257 Segment.Data.MemoryIndex = (Segment.Data.InitFlags & wasm::WASM_SEGMENT_HAS_MEMINDEX) 1258 ? readVaruint32(Ctx) : 0; 1259 if ((Segment.Data.InitFlags & wasm::WASM_SEGMENT_IS_PASSIVE) == 0) { 1260 if (Error Err = readInitExpr(Segment.Data.Offset, Ctx)) 1261 return Err; 1262 } else { 1263 Segment.Data.Offset.Opcode = wasm::WASM_OPCODE_I32_CONST; 1264 Segment.Data.Offset.Value.Int32 = 0; 1265 } 1266 uint32_t Size = readVaruint32(Ctx); 1267 if (Size > (size_t)(Ctx.End - Ctx.Ptr)) 1268 return make_error<GenericBinaryError>("Invalid segment size", 1269 object_error::parse_failed); 1270 Segment.Data.Content = ArrayRef<uint8_t>(Ctx.Ptr, Size); 1271 // The rest of these Data fields are set later, when reading in the linking 1272 // metadata section. 1273 Segment.Data.Alignment = 0; 1274 Segment.Data.LinkerFlags = 0; 1275 Segment.Data.Comdat = UINT32_MAX; 1276 Segment.SectionOffset = Ctx.Ptr - Ctx.Start; 1277 Ctx.Ptr += Size; 1278 DataSegments.push_back(Segment); 1279 } 1280 if (Ctx.Ptr != Ctx.End) 1281 return make_error<GenericBinaryError>("Data section ended prematurely", 1282 object_error::parse_failed); 1283 return Error::success(); 1284 } 1285 1286 Error WasmObjectFile::parseDataCountSection(ReadContext &Ctx) { 1287 DataCount = readVaruint32(Ctx); 1288 return Error::success(); 1289 } 1290 1291 const wasm::WasmObjectHeader &WasmObjectFile::getHeader() const { 1292 return Header; 1293 } 1294 1295 void WasmObjectFile::moveSymbolNext(DataRefImpl &Symb) const { Symb.d.b++; } 1296 1297 Expected<uint32_t> WasmObjectFile::getSymbolFlags(DataRefImpl Symb) const { 1298 uint32_t Result = SymbolRef::SF_None; 1299 const WasmSymbol &Sym = getWasmSymbol(Symb); 1300 1301 LLVM_DEBUG(dbgs() << "getSymbolFlags: ptr=" << &Sym << " " << Sym << "\n"); 1302 if (Sym.isBindingWeak()) 1303 Result |= SymbolRef::SF_Weak; 1304 if (!Sym.isBindingLocal()) 1305 Result |= SymbolRef::SF_Global; 1306 if (Sym.isHidden()) 1307 Result |= SymbolRef::SF_Hidden; 1308 if (!Sym.isDefined()) 1309 Result |= SymbolRef::SF_Undefined; 1310 if (Sym.isTypeFunction()) 1311 Result |= SymbolRef::SF_Executable; 1312 return Result; 1313 } 1314 1315 basic_symbol_iterator WasmObjectFile::symbol_begin() const { 1316 DataRefImpl Ref; 1317 Ref.d.a = 1; // Arbitrary non-zero value so that Ref.p is non-null 1318 Ref.d.b = 0; // Symbol index 1319 return BasicSymbolRef(Ref, this); 1320 } 1321 1322 basic_symbol_iterator WasmObjectFile::symbol_end() const { 1323 DataRefImpl Ref; 1324 Ref.d.a = 1; // Arbitrary non-zero value so that Ref.p is non-null 1325 Ref.d.b = Symbols.size(); // Symbol index 1326 return BasicSymbolRef(Ref, this); 1327 } 1328 1329 const WasmSymbol &WasmObjectFile::getWasmSymbol(const DataRefImpl &Symb) const { 1330 return Symbols[Symb.d.b]; 1331 } 1332 1333 const WasmSymbol &WasmObjectFile::getWasmSymbol(const SymbolRef &Symb) const { 1334 return getWasmSymbol(Symb.getRawDataRefImpl()); 1335 } 1336 1337 Expected<StringRef> WasmObjectFile::getSymbolName(DataRefImpl Symb) const { 1338 return getWasmSymbol(Symb).Info.Name; 1339 } 1340 1341 Expected<uint64_t> WasmObjectFile::getSymbolAddress(DataRefImpl Symb) const { 1342 auto &Sym = getWasmSymbol(Symb); 1343 if (Sym.Info.Kind == wasm::WASM_SYMBOL_TYPE_FUNCTION && 1344 isDefinedFunctionIndex(Sym.Info.ElementIndex)) 1345 return getDefinedFunction(Sym.Info.ElementIndex).CodeSectionOffset; 1346 else 1347 return getSymbolValue(Symb); 1348 } 1349 1350 uint64_t WasmObjectFile::getWasmSymbolValue(const WasmSymbol &Sym) const { 1351 switch (Sym.Info.Kind) { 1352 case wasm::WASM_SYMBOL_TYPE_FUNCTION: 1353 case wasm::WASM_SYMBOL_TYPE_GLOBAL: 1354 case wasm::WASM_SYMBOL_TYPE_EVENT: 1355 return Sym.Info.ElementIndex; 1356 case wasm::WASM_SYMBOL_TYPE_DATA: { 1357 // The value of a data symbol is the segment offset, plus the symbol 1358 // offset within the segment. 1359 uint32_t SegmentIndex = Sym.Info.DataRef.Segment; 1360 const wasm::WasmDataSegment &Segment = DataSegments[SegmentIndex].Data; 1361 if (Segment.Offset.Opcode == wasm::WASM_OPCODE_I32_CONST) { 1362 return Segment.Offset.Value.Int32 + Sym.Info.DataRef.Offset; 1363 } else if (Segment.Offset.Opcode == wasm::WASM_OPCODE_I64_CONST) { 1364 return Segment.Offset.Value.Int64 + Sym.Info.DataRef.Offset; 1365 } else { 1366 llvm_unreachable("unknown init expr opcode"); 1367 } 1368 } 1369 case wasm::WASM_SYMBOL_TYPE_SECTION: 1370 return 0; 1371 } 1372 llvm_unreachable("invalid symbol type"); 1373 } 1374 1375 uint64_t WasmObjectFile::getSymbolValueImpl(DataRefImpl Symb) const { 1376 return getWasmSymbolValue(getWasmSymbol(Symb)); 1377 } 1378 1379 uint32_t WasmObjectFile::getSymbolAlignment(DataRefImpl Symb) const { 1380 llvm_unreachable("not yet implemented"); 1381 return 0; 1382 } 1383 1384 uint64_t WasmObjectFile::getCommonSymbolSizeImpl(DataRefImpl Symb) const { 1385 llvm_unreachable("not yet implemented"); 1386 return 0; 1387 } 1388 1389 Expected<SymbolRef::Type> 1390 WasmObjectFile::getSymbolType(DataRefImpl Symb) const { 1391 const WasmSymbol &Sym = getWasmSymbol(Symb); 1392 1393 switch (Sym.Info.Kind) { 1394 case wasm::WASM_SYMBOL_TYPE_FUNCTION: 1395 return SymbolRef::ST_Function; 1396 case wasm::WASM_SYMBOL_TYPE_GLOBAL: 1397 return SymbolRef::ST_Other; 1398 case wasm::WASM_SYMBOL_TYPE_DATA: 1399 return SymbolRef::ST_Data; 1400 case wasm::WASM_SYMBOL_TYPE_SECTION: 1401 return SymbolRef::ST_Debug; 1402 case wasm::WASM_SYMBOL_TYPE_EVENT: 1403 return SymbolRef::ST_Other; 1404 } 1405 1406 llvm_unreachable("Unknown WasmSymbol::SymbolType"); 1407 return SymbolRef::ST_Other; 1408 } 1409 1410 Expected<section_iterator> 1411 WasmObjectFile::getSymbolSection(DataRefImpl Symb) const { 1412 const WasmSymbol &Sym = getWasmSymbol(Symb); 1413 if (Sym.isUndefined()) 1414 return section_end(); 1415 1416 DataRefImpl Ref; 1417 Ref.d.a = getSymbolSectionIdImpl(Sym); 1418 return section_iterator(SectionRef(Ref, this)); 1419 } 1420 1421 uint32_t WasmObjectFile::getSymbolSectionId(SymbolRef Symb) const { 1422 const WasmSymbol &Sym = getWasmSymbol(Symb); 1423 return getSymbolSectionIdImpl(Sym); 1424 } 1425 1426 uint32_t WasmObjectFile::getSymbolSectionIdImpl(const WasmSymbol &Sym) const { 1427 switch (Sym.Info.Kind) { 1428 case wasm::WASM_SYMBOL_TYPE_FUNCTION: 1429 return CodeSection; 1430 case wasm::WASM_SYMBOL_TYPE_GLOBAL: 1431 return GlobalSection; 1432 case wasm::WASM_SYMBOL_TYPE_DATA: 1433 return DataSection; 1434 case wasm::WASM_SYMBOL_TYPE_SECTION: 1435 return Sym.Info.ElementIndex; 1436 case wasm::WASM_SYMBOL_TYPE_EVENT: 1437 return EventSection; 1438 default: 1439 llvm_unreachable("Unknown WasmSymbol::SymbolType"); 1440 } 1441 } 1442 1443 void WasmObjectFile::moveSectionNext(DataRefImpl &Sec) const { Sec.d.a++; } 1444 1445 Expected<StringRef> WasmObjectFile::getSectionName(DataRefImpl Sec) const { 1446 const WasmSection &S = Sections[Sec.d.a]; 1447 #define ECase(X) \ 1448 case wasm::WASM_SEC_##X: \ 1449 return #X; 1450 switch (S.Type) { 1451 ECase(TYPE); 1452 ECase(IMPORT); 1453 ECase(FUNCTION); 1454 ECase(TABLE); 1455 ECase(MEMORY); 1456 ECase(GLOBAL); 1457 ECase(EVENT); 1458 ECase(EXPORT); 1459 ECase(START); 1460 ECase(ELEM); 1461 ECase(CODE); 1462 ECase(DATA); 1463 ECase(DATACOUNT); 1464 case wasm::WASM_SEC_CUSTOM: 1465 return S.Name; 1466 default: 1467 return createStringError(object_error::invalid_section_index, ""); 1468 } 1469 #undef ECase 1470 } 1471 1472 uint64_t WasmObjectFile::getSectionAddress(DataRefImpl Sec) const { return 0; } 1473 1474 uint64_t WasmObjectFile::getSectionIndex(DataRefImpl Sec) const { 1475 return Sec.d.a; 1476 } 1477 1478 uint64_t WasmObjectFile::getSectionSize(DataRefImpl Sec) const { 1479 const WasmSection &S = Sections[Sec.d.a]; 1480 return S.Content.size(); 1481 } 1482 1483 Expected<ArrayRef<uint8_t>> 1484 WasmObjectFile::getSectionContents(DataRefImpl Sec) const { 1485 const WasmSection &S = Sections[Sec.d.a]; 1486 // This will never fail since wasm sections can never be empty (user-sections 1487 // must have a name and non-user sections each have a defined structure). 1488 return S.Content; 1489 } 1490 1491 uint64_t WasmObjectFile::getSectionAlignment(DataRefImpl Sec) const { 1492 return 1; 1493 } 1494 1495 bool WasmObjectFile::isSectionCompressed(DataRefImpl Sec) const { 1496 return false; 1497 } 1498 1499 bool WasmObjectFile::isSectionText(DataRefImpl Sec) const { 1500 return getWasmSection(Sec).Type == wasm::WASM_SEC_CODE; 1501 } 1502 1503 bool WasmObjectFile::isSectionData(DataRefImpl Sec) const { 1504 return getWasmSection(Sec).Type == wasm::WASM_SEC_DATA; 1505 } 1506 1507 bool WasmObjectFile::isSectionBSS(DataRefImpl Sec) const { return false; } 1508 1509 bool WasmObjectFile::isSectionVirtual(DataRefImpl Sec) const { return false; } 1510 1511 relocation_iterator WasmObjectFile::section_rel_begin(DataRefImpl Ref) const { 1512 DataRefImpl RelocRef; 1513 RelocRef.d.a = Ref.d.a; 1514 RelocRef.d.b = 0; 1515 return relocation_iterator(RelocationRef(RelocRef, this)); 1516 } 1517 1518 relocation_iterator WasmObjectFile::section_rel_end(DataRefImpl Ref) const { 1519 const WasmSection &Sec = getWasmSection(Ref); 1520 DataRefImpl RelocRef; 1521 RelocRef.d.a = Ref.d.a; 1522 RelocRef.d.b = Sec.Relocations.size(); 1523 return relocation_iterator(RelocationRef(RelocRef, this)); 1524 } 1525 1526 void WasmObjectFile::moveRelocationNext(DataRefImpl &Rel) const { Rel.d.b++; } 1527 1528 uint64_t WasmObjectFile::getRelocationOffset(DataRefImpl Ref) const { 1529 const wasm::WasmRelocation &Rel = getWasmRelocation(Ref); 1530 return Rel.Offset; 1531 } 1532 1533 symbol_iterator WasmObjectFile::getRelocationSymbol(DataRefImpl Ref) const { 1534 const wasm::WasmRelocation &Rel = getWasmRelocation(Ref); 1535 if (Rel.Type == wasm::R_WASM_TYPE_INDEX_LEB) 1536 return symbol_end(); 1537 DataRefImpl Sym; 1538 Sym.d.a = 1; 1539 Sym.d.b = Rel.Index; 1540 return symbol_iterator(SymbolRef(Sym, this)); 1541 } 1542 1543 uint64_t WasmObjectFile::getRelocationType(DataRefImpl Ref) const { 1544 const wasm::WasmRelocation &Rel = getWasmRelocation(Ref); 1545 return Rel.Type; 1546 } 1547 1548 void WasmObjectFile::getRelocationTypeName( 1549 DataRefImpl Ref, SmallVectorImpl<char> &Result) const { 1550 const wasm::WasmRelocation &Rel = getWasmRelocation(Ref); 1551 StringRef Res = "Unknown"; 1552 1553 #define WASM_RELOC(name, value) \ 1554 case wasm::name: \ 1555 Res = #name; \ 1556 break; 1557 1558 switch (Rel.Type) { 1559 #include "llvm/BinaryFormat/WasmRelocs.def" 1560 } 1561 1562 #undef WASM_RELOC 1563 1564 Result.append(Res.begin(), Res.end()); 1565 } 1566 1567 section_iterator WasmObjectFile::section_begin() const { 1568 DataRefImpl Ref; 1569 Ref.d.a = 0; 1570 return section_iterator(SectionRef(Ref, this)); 1571 } 1572 1573 section_iterator WasmObjectFile::section_end() const { 1574 DataRefImpl Ref; 1575 Ref.d.a = Sections.size(); 1576 return section_iterator(SectionRef(Ref, this)); 1577 } 1578 1579 uint8_t WasmObjectFile::getBytesInAddress() const { return 4; } 1580 1581 StringRef WasmObjectFile::getFileFormatName() const { return "WASM"; } 1582 1583 Triple::ArchType WasmObjectFile::getArch() const { return Triple::wasm32; } 1584 1585 SubtargetFeatures WasmObjectFile::getFeatures() const { 1586 return SubtargetFeatures(); 1587 } 1588 1589 bool WasmObjectFile::isRelocatableObject() const { return HasLinkingSection; } 1590 1591 bool WasmObjectFile::isSharedObject() const { return HasDylinkSection; } 1592 1593 const WasmSection &WasmObjectFile::getWasmSection(DataRefImpl Ref) const { 1594 assert(Ref.d.a < Sections.size()); 1595 return Sections[Ref.d.a]; 1596 } 1597 1598 const WasmSection & 1599 WasmObjectFile::getWasmSection(const SectionRef &Section) const { 1600 return getWasmSection(Section.getRawDataRefImpl()); 1601 } 1602 1603 const wasm::WasmRelocation & 1604 WasmObjectFile::getWasmRelocation(const RelocationRef &Ref) const { 1605 return getWasmRelocation(Ref.getRawDataRefImpl()); 1606 } 1607 1608 const wasm::WasmRelocation & 1609 WasmObjectFile::getWasmRelocation(DataRefImpl Ref) const { 1610 assert(Ref.d.a < Sections.size()); 1611 const WasmSection &Sec = Sections[Ref.d.a]; 1612 assert(Ref.d.b < Sec.Relocations.size()); 1613 return Sec.Relocations[Ref.d.b]; 1614 } 1615 1616 int WasmSectionOrderChecker::getSectionOrder(unsigned ID, 1617 StringRef CustomSectionName) { 1618 switch (ID) { 1619 case wasm::WASM_SEC_CUSTOM: 1620 return StringSwitch<unsigned>(CustomSectionName) 1621 .Case("dylink", WASM_SEC_ORDER_DYLINK) 1622 .Case("linking", WASM_SEC_ORDER_LINKING) 1623 .StartsWith("reloc.", WASM_SEC_ORDER_RELOC) 1624 .Case("name", WASM_SEC_ORDER_NAME) 1625 .Case("producers", WASM_SEC_ORDER_PRODUCERS) 1626 .Case("target_features", WASM_SEC_ORDER_TARGET_FEATURES) 1627 .Default(WASM_SEC_ORDER_NONE); 1628 case wasm::WASM_SEC_TYPE: 1629 return WASM_SEC_ORDER_TYPE; 1630 case wasm::WASM_SEC_IMPORT: 1631 return WASM_SEC_ORDER_IMPORT; 1632 case wasm::WASM_SEC_FUNCTION: 1633 return WASM_SEC_ORDER_FUNCTION; 1634 case wasm::WASM_SEC_TABLE: 1635 return WASM_SEC_ORDER_TABLE; 1636 case wasm::WASM_SEC_MEMORY: 1637 return WASM_SEC_ORDER_MEMORY; 1638 case wasm::WASM_SEC_GLOBAL: 1639 return WASM_SEC_ORDER_GLOBAL; 1640 case wasm::WASM_SEC_EXPORT: 1641 return WASM_SEC_ORDER_EXPORT; 1642 case wasm::WASM_SEC_START: 1643 return WASM_SEC_ORDER_START; 1644 case wasm::WASM_SEC_ELEM: 1645 return WASM_SEC_ORDER_ELEM; 1646 case wasm::WASM_SEC_CODE: 1647 return WASM_SEC_ORDER_CODE; 1648 case wasm::WASM_SEC_DATA: 1649 return WASM_SEC_ORDER_DATA; 1650 case wasm::WASM_SEC_DATACOUNT: 1651 return WASM_SEC_ORDER_DATACOUNT; 1652 case wasm::WASM_SEC_EVENT: 1653 return WASM_SEC_ORDER_EVENT; 1654 default: 1655 return WASM_SEC_ORDER_NONE; 1656 } 1657 } 1658 1659 // Represents the edges in a directed graph where any node B reachable from node 1660 // A is not allowed to appear before A in the section ordering, but may appear 1661 // afterward. 1662 int WasmSectionOrderChecker::DisallowedPredecessors 1663 [WASM_NUM_SEC_ORDERS][WASM_NUM_SEC_ORDERS] = { 1664 // WASM_SEC_ORDER_NONE 1665 {}, 1666 // WASM_SEC_ORDER_TYPE 1667 {WASM_SEC_ORDER_TYPE, WASM_SEC_ORDER_IMPORT}, 1668 // WASM_SEC_ORDER_IMPORT 1669 {WASM_SEC_ORDER_IMPORT, WASM_SEC_ORDER_FUNCTION}, 1670 // WASM_SEC_ORDER_FUNCTION 1671 {WASM_SEC_ORDER_FUNCTION, WASM_SEC_ORDER_TABLE}, 1672 // WASM_SEC_ORDER_TABLE 1673 {WASM_SEC_ORDER_TABLE, WASM_SEC_ORDER_MEMORY}, 1674 // WASM_SEC_ORDER_MEMORY 1675 {WASM_SEC_ORDER_MEMORY, WASM_SEC_ORDER_EVENT}, 1676 // WASM_SEC_ORDER_EVENT 1677 {WASM_SEC_ORDER_EVENT, WASM_SEC_ORDER_GLOBAL}, 1678 // WASM_SEC_ORDER_GLOBAL 1679 {WASM_SEC_ORDER_GLOBAL, WASM_SEC_ORDER_EXPORT}, 1680 // WASM_SEC_ORDER_EXPORT 1681 {WASM_SEC_ORDER_EXPORT, WASM_SEC_ORDER_START}, 1682 // WASM_SEC_ORDER_START 1683 {WASM_SEC_ORDER_START, WASM_SEC_ORDER_ELEM}, 1684 // WASM_SEC_ORDER_ELEM 1685 {WASM_SEC_ORDER_ELEM, WASM_SEC_ORDER_DATACOUNT}, 1686 // WASM_SEC_ORDER_DATACOUNT 1687 {WASM_SEC_ORDER_DATACOUNT, WASM_SEC_ORDER_CODE}, 1688 // WASM_SEC_ORDER_CODE 1689 {WASM_SEC_ORDER_CODE, WASM_SEC_ORDER_DATA}, 1690 // WASM_SEC_ORDER_DATA 1691 {WASM_SEC_ORDER_DATA, WASM_SEC_ORDER_LINKING}, 1692 1693 // Custom Sections 1694 // WASM_SEC_ORDER_DYLINK 1695 {WASM_SEC_ORDER_DYLINK, WASM_SEC_ORDER_TYPE}, 1696 // WASM_SEC_ORDER_LINKING 1697 {WASM_SEC_ORDER_LINKING, WASM_SEC_ORDER_RELOC, WASM_SEC_ORDER_NAME}, 1698 // WASM_SEC_ORDER_RELOC (can be repeated) 1699 {}, 1700 // WASM_SEC_ORDER_NAME 1701 {WASM_SEC_ORDER_NAME, WASM_SEC_ORDER_PRODUCERS}, 1702 // WASM_SEC_ORDER_PRODUCERS 1703 {WASM_SEC_ORDER_PRODUCERS, WASM_SEC_ORDER_TARGET_FEATURES}, 1704 // WASM_SEC_ORDER_TARGET_FEATURES 1705 {WASM_SEC_ORDER_TARGET_FEATURES}}; 1706 1707 bool WasmSectionOrderChecker::isValidSectionOrder(unsigned ID, 1708 StringRef CustomSectionName) { 1709 int Order = getSectionOrder(ID, CustomSectionName); 1710 if (Order == WASM_SEC_ORDER_NONE) 1711 return true; 1712 1713 // Disallowed predecessors we need to check for 1714 SmallVector<int, WASM_NUM_SEC_ORDERS> WorkList; 1715 1716 // Keep track of completed checks to avoid repeating work 1717 bool Checked[WASM_NUM_SEC_ORDERS] = {}; 1718 1719 int Curr = Order; 1720 while (true) { 1721 // Add new disallowed predecessors to work list 1722 for (size_t I = 0;; ++I) { 1723 int Next = DisallowedPredecessors[Curr][I]; 1724 if (Next == WASM_SEC_ORDER_NONE) 1725 break; 1726 if (Checked[Next]) 1727 continue; 1728 WorkList.push_back(Next); 1729 Checked[Next] = true; 1730 } 1731 1732 if (WorkList.empty()) 1733 break; 1734 1735 // Consider next disallowed predecessor 1736 Curr = WorkList.pop_back_val(); 1737 if (Seen[Curr]) 1738 return false; 1739 } 1740 1741 // Have not seen any disallowed predecessors 1742 Seen[Order] = true; 1743 return true; 1744 } 1745