//===- Wasm.h - Wasm object file implementation -----------------*- C++ -*-===// // // 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 // //===----------------------------------------------------------------------===// // // This file declares the WasmObjectFile class, which implements the ObjectFile // interface for Wasm files. // // See: https://github.com/WebAssembly/design/blob/master/BinaryEncoding.md // //===----------------------------------------------------------------------===// #ifndef LLVM_OBJECT_WASM_H #define LLVM_OBJECT_WASM_H #include "llvm/ADT/ArrayRef.h" #include "llvm/ADT/StringMap.h" #include "llvm/ADT/StringRef.h" #include "llvm/BinaryFormat/Wasm.h" #include "llvm/Config/llvm-config.h" #include "llvm/MC/MCSymbolWasm.h" #include "llvm/Object/Binary.h" #include "llvm/Object/ObjectFile.h" #include "llvm/Support/Error.h" #include "llvm/Support/MemoryBuffer.h" #include #include #include namespace llvm { namespace object { class WasmSymbol { public: WasmSymbol(const wasm::WasmSymbolInfo &Info, const wasm::WasmGlobalType *GlobalType, const wasm::WasmEventType *EventType, const wasm::WasmSignature *Signature) : Info(Info), GlobalType(GlobalType), EventType(EventType), Signature(Signature) {} const wasm::WasmSymbolInfo &Info; const wasm::WasmGlobalType *GlobalType; const wasm::WasmEventType *EventType; const wasm::WasmSignature *Signature; bool isTypeFunction() const { return Info.Kind == wasm::WASM_SYMBOL_TYPE_FUNCTION; } bool isTypeData() const { return Info.Kind == wasm::WASM_SYMBOL_TYPE_DATA; } bool isTypeGlobal() const { return Info.Kind == wasm::WASM_SYMBOL_TYPE_GLOBAL; } bool isTypeSection() const { return Info.Kind == wasm::WASM_SYMBOL_TYPE_SECTION; } bool isTypeEvent() const { return Info.Kind == wasm::WASM_SYMBOL_TYPE_EVENT; } bool isDefined() const { return !isUndefined(); } bool isUndefined() const { return (Info.Flags & wasm::WASM_SYMBOL_UNDEFINED) != 0; } bool isBindingWeak() const { return getBinding() == wasm::WASM_SYMBOL_BINDING_WEAK; } bool isBindingGlobal() const { return getBinding() == wasm::WASM_SYMBOL_BINDING_GLOBAL; } bool isBindingLocal() const { return getBinding() == wasm::WASM_SYMBOL_BINDING_LOCAL; } unsigned getBinding() const { return Info.Flags & wasm::WASM_SYMBOL_BINDING_MASK; } bool isHidden() const { return getVisibility() == wasm::WASM_SYMBOL_VISIBILITY_HIDDEN; } unsigned getVisibility() const { return Info.Flags & wasm::WASM_SYMBOL_VISIBILITY_MASK; } void print(raw_ostream &Out) const; #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) LLVM_DUMP_METHOD void dump() const; #endif }; struct WasmSection { WasmSection() = default; uint32_t Type = 0; // Section type (See below) uint32_t Offset = 0; // Offset with in the file StringRef Name; // Section name (User-defined sections only) ArrayRef Content; // Section content std::vector Relocations; // Relocations for this section }; struct WasmSegment { uint32_t SectionOffset; wasm::WasmDataSegment Data; }; class WasmObjectFile : public ObjectFile { public: WasmObjectFile(MemoryBufferRef Object, Error &Err); const wasm::WasmObjectHeader &getHeader() const; const WasmSymbol &getWasmSymbol(const DataRefImpl &Symb) const; const WasmSymbol &getWasmSymbol(const SymbolRef &Symbol) const; const WasmSection &getWasmSection(const SectionRef &Section) const; const wasm::WasmRelocation &getWasmRelocation(const RelocationRef &Ref) const; static bool classof(const Binary *v) { return v->isWasm(); } const wasm::WasmDylinkInfo &dylinkInfo() const { return DylinkInfo; } const wasm::WasmProducerInfo &getProducerInfo() const { return ProducerInfo; } ArrayRef getTargetFeatures() const { return TargetFeatures; } ArrayRef types() const { return Signatures; } ArrayRef functionTypes() const { return FunctionTypes; } ArrayRef imports() const { return Imports; } ArrayRef tables() const { return Tables; } ArrayRef memories() const { return Memories; } ArrayRef globals() const { return Globals; } ArrayRef events() const { return Events; } ArrayRef exports() const { return Exports; } ArrayRef syms() const { return Symbols; } const wasm::WasmLinkingData &linkingData() const { return LinkingData; } uint32_t getNumberOfSymbols() const { return Symbols.size(); } ArrayRef elements() const { return ElemSegments; } ArrayRef dataSegments() const { return DataSegments; } ArrayRef functions() const { return Functions; } ArrayRef debugNames() const { return DebugNames; } uint32_t startFunction() const { return StartFunction; } uint32_t getNumImportedGlobals() const { return NumImportedGlobals; } uint32_t getNumImportedFunctions() const { return NumImportedFunctions; } uint32_t getNumImportedEvents() const { return NumImportedEvents; } void moveSymbolNext(DataRefImpl &Symb) const override; uint32_t getSymbolFlags(DataRefImpl Symb) const override; basic_symbol_iterator symbol_begin() const override; basic_symbol_iterator symbol_end() const override; Expected getSymbolName(DataRefImpl Symb) const override; Expected getSymbolAddress(DataRefImpl Symb) const override; uint64_t getWasmSymbolValue(const WasmSymbol &Sym) const; uint64_t getSymbolValueImpl(DataRefImpl Symb) const override; uint32_t getSymbolAlignment(DataRefImpl Symb) const override; uint64_t getCommonSymbolSizeImpl(DataRefImpl Symb) const override; Expected getSymbolType(DataRefImpl Symb) const override; Expected getSymbolSection(DataRefImpl Symb) const override; // Overrides from SectionRef. void moveSectionNext(DataRefImpl &Sec) const override; Expected getSectionName(DataRefImpl Sec) const override; uint64_t getSectionAddress(DataRefImpl Sec) const override; uint64_t getSectionIndex(DataRefImpl Sec) const override; uint64_t getSectionSize(DataRefImpl Sec) const override; Expected> getSectionContents(DataRefImpl Sec) const override; uint64_t getSectionAlignment(DataRefImpl Sec) const override; bool isSectionCompressed(DataRefImpl Sec) const override; bool isSectionText(DataRefImpl Sec) const override; bool isSectionData(DataRefImpl Sec) const override; bool isSectionBSS(DataRefImpl Sec) const override; bool isSectionVirtual(DataRefImpl Sec) const override; bool isSectionBitcode(DataRefImpl Sec) const override; relocation_iterator section_rel_begin(DataRefImpl Sec) const override; relocation_iterator section_rel_end(DataRefImpl Sec) const override; // Overrides from RelocationRef. void moveRelocationNext(DataRefImpl &Rel) const override; uint64_t getRelocationOffset(DataRefImpl Rel) const override; symbol_iterator getRelocationSymbol(DataRefImpl Rel) const override; uint64_t getRelocationType(DataRefImpl Rel) const override; void getRelocationTypeName(DataRefImpl Rel, SmallVectorImpl &Result) const override; section_iterator section_begin() const override; section_iterator section_end() const override; uint8_t getBytesInAddress() const override; StringRef getFileFormatName() const override; Triple::ArchType getArch() const override; SubtargetFeatures getFeatures() const override; bool isRelocatableObject() const override; bool isSharedObject() const; struct ReadContext { const uint8_t *Start; const uint8_t *Ptr; const uint8_t *End; }; private: bool isValidFunctionIndex(uint32_t Index) const; bool isDefinedFunctionIndex(uint32_t Index) const; bool isValidGlobalIndex(uint32_t Index) const; bool isDefinedGlobalIndex(uint32_t Index) const; bool isValidEventIndex(uint32_t Index) const; bool isDefinedEventIndex(uint32_t Index) const; bool isValidFunctionSymbol(uint32_t Index) const; bool isValidGlobalSymbol(uint32_t Index) const; bool isValidEventSymbol(uint32_t Index) const; bool isValidDataSymbol(uint32_t Index) const; bool isValidSectionSymbol(uint32_t Index) const; wasm::WasmFunction &getDefinedFunction(uint32_t Index); const wasm::WasmFunction &getDefinedFunction(uint32_t Index) const; wasm::WasmGlobal &getDefinedGlobal(uint32_t Index); wasm::WasmEvent &getDefinedEvent(uint32_t Index); const WasmSection &getWasmSection(DataRefImpl Ref) const; const wasm::WasmRelocation &getWasmRelocation(DataRefImpl Ref) const; Error parseSection(WasmSection &Sec); Error parseCustomSection(WasmSection &Sec, ReadContext &Ctx); // Standard section types Error parseTypeSection(ReadContext &Ctx); Error parseImportSection(ReadContext &Ctx); Error parseFunctionSection(ReadContext &Ctx); Error parseTableSection(ReadContext &Ctx); Error parseMemorySection(ReadContext &Ctx); Error parseGlobalSection(ReadContext &Ctx); Error parseEventSection(ReadContext &Ctx); Error parseExportSection(ReadContext &Ctx); Error parseStartSection(ReadContext &Ctx); Error parseElemSection(ReadContext &Ctx); Error parseCodeSection(ReadContext &Ctx); Error parseDataSection(ReadContext &Ctx); Error parseDataCountSection(ReadContext &Ctx); // Custom section types Error parseDylinkSection(ReadContext &Ctx); Error parseNameSection(ReadContext &Ctx); Error parseLinkingSection(ReadContext &Ctx); Error parseLinkingSectionSymtab(ReadContext &Ctx); Error parseLinkingSectionComdat(ReadContext &Ctx); Error parseProducersSection(ReadContext &Ctx); Error parseTargetFeaturesSection(ReadContext &Ctx); Error parseRelocSection(StringRef Name, ReadContext &Ctx); wasm::WasmObjectHeader Header; std::vector Sections; wasm::WasmDylinkInfo DylinkInfo; wasm::WasmProducerInfo ProducerInfo; std::vector TargetFeatures; std::vector Signatures; std::vector FunctionTypes; std::vector Tables; std::vector Memories; std::vector Globals; std::vector Events; std::vector Imports; std::vector Exports; std::vector ElemSegments; std::vector DataSegments; llvm::Optional DataCount; std::vector Functions; std::vector Symbols; std::vector DebugNames; uint32_t StartFunction = -1; bool HasLinkingSection = false; bool HasDylinkSection = false; wasm::WasmLinkingData LinkingData; uint32_t NumImportedGlobals = 0; uint32_t NumImportedFunctions = 0; uint32_t NumImportedEvents = 0; uint32_t CodeSection = 0; uint32_t DataSection = 0; uint32_t GlobalSection = 0; uint32_t EventSection = 0; }; class WasmSectionOrderChecker { public: // We define orders for all core wasm sections and known custom sections. enum : int { // Sentinel, must be zero WASM_SEC_ORDER_NONE = 0, // Core sections WASM_SEC_ORDER_TYPE, WASM_SEC_ORDER_IMPORT, WASM_SEC_ORDER_FUNCTION, WASM_SEC_ORDER_TABLE, WASM_SEC_ORDER_MEMORY, WASM_SEC_ORDER_GLOBAL, WASM_SEC_ORDER_EVENT, WASM_SEC_ORDER_EXPORT, WASM_SEC_ORDER_START, WASM_SEC_ORDER_ELEM, WASM_SEC_ORDER_DATACOUNT, WASM_SEC_ORDER_CODE, WASM_SEC_ORDER_DATA, // Custom sections // "dylink" should be the very first section in the module WASM_SEC_ORDER_DYLINK, // "linking" section requires DATA section in order to validate data symbols WASM_SEC_ORDER_LINKING, // Must come after "linking" section in order to validate reloc indexes. WASM_SEC_ORDER_RELOC, // "name" section must appear after DATA. Comes after "linking" to allow // symbol table to set default function name. WASM_SEC_ORDER_NAME, // "producers" section must appear after "name" section. WASM_SEC_ORDER_PRODUCERS, // "target_features" section must appear after producers section WASM_SEC_ORDER_TARGET_FEATURES, // Must be last WASM_NUM_SEC_ORDERS }; // Sections that may or may not be present, but cannot be predecessors static int DisallowedPredecessors[WASM_NUM_SEC_ORDERS][WASM_NUM_SEC_ORDERS]; bool isValidSectionOrder(unsigned ID, StringRef CustomSectionName = ""); private: bool Seen[WASM_NUM_SEC_ORDERS] = {}; // Sections that have been seen already // Returns -1 for unknown sections. int getSectionOrder(unsigned ID, StringRef CustomSectionName = ""); }; } // end namespace object inline raw_ostream &operator<<(raw_ostream &OS, const object::WasmSymbol &Sym) { Sym.print(OS); return OS; } } // end namespace llvm #endif // LLVM_OBJECT_WASM_H