| //===- Wasm.h - Wasm object file format -------------------------*- 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 defines manifest constants for the wasm object file format. |
| // See: https://github.com/WebAssembly/design/blob/master/BinaryEncoding.md |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_BINARYFORMAT_WASM_H |
| #define LLVM_BINARYFORMAT_WASM_H |
| |
| #include "llvm/ADT/ArrayRef.h" |
| #include "llvm/ADT/SmallVector.h" |
| |
| namespace llvm { |
| namespace wasm { |
| |
| // Object file magic string. |
| const char WasmMagic[] = {'\0', 'a', 's', 'm'}; |
| // Wasm binary format version |
| const uint32_t WasmVersion = 0x1; |
| // Wasm linking metadata version |
| const uint32_t WasmMetadataVersion = 0x2; |
| // Wasm uses a 64k page size |
| const uint32_t WasmPageSize = 65536; |
| |
| struct WasmObjectHeader { |
| StringRef Magic; |
| uint32_t Version; |
| }; |
| |
| struct WasmDylinkInfo { |
| uint32_t MemorySize; // Memory size in bytes |
| uint32_t MemoryAlignment; // P2 alignment of memory |
| uint32_t TableSize; // Table size in elements |
| uint32_t TableAlignment; // P2 alignment of table |
| std::vector<StringRef> Needed; // Shared library depenedencies |
| }; |
| |
| struct WasmProducerInfo { |
| std::vector<std::pair<std::string, std::string>> Languages; |
| std::vector<std::pair<std::string, std::string>> Tools; |
| std::vector<std::pair<std::string, std::string>> SDKs; |
| }; |
| |
| struct WasmFeatureEntry { |
| uint8_t Prefix; |
| std::string Name; |
| }; |
| |
| struct WasmExport { |
| StringRef Name; |
| uint8_t Kind; |
| uint32_t Index; |
| }; |
| |
| struct WasmLimits { |
| uint8_t Flags; |
| uint32_t Initial; |
| uint32_t Maximum; |
| }; |
| |
| struct WasmTable { |
| uint8_t ElemType; |
| WasmLimits Limits; |
| }; |
| |
| struct WasmInitExpr { |
| uint8_t Opcode; |
| union { |
| int32_t Int32; |
| int64_t Int64; |
| int32_t Float32; |
| int64_t Float64; |
| uint32_t Global; |
| } Value; |
| }; |
| |
| struct WasmGlobalType { |
| uint8_t Type; |
| bool Mutable; |
| }; |
| |
| struct WasmGlobal { |
| uint32_t Index; |
| WasmGlobalType Type; |
| WasmInitExpr InitExpr; |
| StringRef SymbolName; // from the "linking" section |
| }; |
| |
| struct WasmEventType { |
| // Kind of event. Currently only WASM_EVENT_ATTRIBUTE_EXCEPTION is possible. |
| uint32_t Attribute; |
| uint32_t SigIndex; |
| }; |
| |
| struct WasmEvent { |
| uint32_t Index; |
| WasmEventType Type; |
| StringRef SymbolName; // from the "linking" section |
| }; |
| |
| struct WasmImport { |
| StringRef Module; |
| StringRef Field; |
| uint8_t Kind; |
| union { |
| uint32_t SigIndex; |
| WasmGlobalType Global; |
| WasmTable Table; |
| WasmLimits Memory; |
| WasmEventType Event; |
| }; |
| }; |
| |
| struct WasmLocalDecl { |
| uint8_t Type; |
| uint32_t Count; |
| }; |
| |
| struct WasmFunction { |
| uint32_t Index; |
| std::vector<WasmLocalDecl> Locals; |
| ArrayRef<uint8_t> Body; |
| uint32_t CodeSectionOffset; |
| uint32_t Size; |
| uint32_t CodeOffset; // start of Locals and Body |
| StringRef SymbolName; // from the "linking" section |
| StringRef DebugName; // from the "name" section |
| uint32_t Comdat; // from the "comdat info" section |
| }; |
| |
| struct WasmDataSegment { |
| uint32_t InitFlags; |
| uint32_t MemoryIndex; // present if InitFlags & WASM_SEGMENT_HAS_MEMINDEX |
| WasmInitExpr Offset; // present if InitFlags & WASM_SEGMENT_IS_PASSIVE == 0 |
| ArrayRef<uint8_t> Content; |
| StringRef Name; // from the "segment info" section |
| uint32_t Alignment; |
| uint32_t LinkerFlags; |
| uint32_t Comdat; // from the "comdat info" section |
| }; |
| |
| struct WasmElemSegment { |
| uint32_t TableIndex; |
| WasmInitExpr Offset; |
| std::vector<uint32_t> Functions; |
| }; |
| |
| // Represents the location of a Wasm data symbol within a WasmDataSegment, as |
| // the index of the segment, and the offset and size within the segment. |
| struct WasmDataReference { |
| uint32_t Segment; |
| uint32_t Offset; |
| uint32_t Size; |
| }; |
| |
| struct WasmRelocation { |
| uint8_t Type; // The type of the relocation. |
| uint32_t Index; // Index into either symbol or type index space. |
| uint64_t Offset; // Offset from the start of the section. |
| int64_t Addend; // A value to add to the symbol. |
| }; |
| |
| struct WasmInitFunc { |
| uint32_t Priority; |
| uint32_t Symbol; |
| }; |
| |
| struct WasmSymbolInfo { |
| StringRef Name; |
| uint8_t Kind; |
| uint32_t Flags; |
| StringRef ImportModule; // For undefined symbols the module of the import |
| StringRef ImportName; // For undefined symbols the name of the import |
| union { |
| // For function or global symbols, the index in function or global index |
| // space. |
| uint32_t ElementIndex; |
| // For a data symbols, the address of the data relative to segment. |
| WasmDataReference DataRef; |
| }; |
| }; |
| |
| struct WasmFunctionName { |
| uint32_t Index; |
| StringRef Name; |
| }; |
| |
| struct WasmLinkingData { |
| uint32_t Version; |
| std::vector<WasmInitFunc> InitFunctions; |
| std::vector<StringRef> Comdats; |
| std::vector<WasmSymbolInfo> SymbolTable; |
| }; |
| |
| enum : unsigned { |
| WASM_SEC_CUSTOM = 0, // Custom / User-defined section |
| WASM_SEC_TYPE = 1, // Function signature declarations |
| WASM_SEC_IMPORT = 2, // Import declarations |
| WASM_SEC_FUNCTION = 3, // Function declarations |
| WASM_SEC_TABLE = 4, // Indirect function table and other tables |
| WASM_SEC_MEMORY = 5, // Memory attributes |
| WASM_SEC_GLOBAL = 6, // Global declarations |
| WASM_SEC_EXPORT = 7, // Exports |
| WASM_SEC_START = 8, // Start function declaration |
| WASM_SEC_ELEM = 9, // Elements section |
| WASM_SEC_CODE = 10, // Function bodies (code) |
| WASM_SEC_DATA = 11, // Data segments |
| WASM_SEC_DATACOUNT = 12, // Data segment count |
| WASM_SEC_EVENT = 13 // Event declarations |
| }; |
| |
| // Type immediate encodings used in various contexts. |
| enum : unsigned { |
| WASM_TYPE_I32 = 0x7F, |
| WASM_TYPE_I64 = 0x7E, |
| WASM_TYPE_F32 = 0x7D, |
| WASM_TYPE_F64 = 0x7C, |
| WASM_TYPE_V128 = 0x7B, |
| WASM_TYPE_FUNCREF = 0x70, |
| WASM_TYPE_EXCEPT_REF = 0x68, |
| WASM_TYPE_FUNC = 0x60, |
| WASM_TYPE_NORESULT = 0x40, // for blocks with no result values |
| }; |
| |
| // Kinds of externals (for imports and exports). |
| enum : unsigned { |
| WASM_EXTERNAL_FUNCTION = 0x0, |
| WASM_EXTERNAL_TABLE = 0x1, |
| WASM_EXTERNAL_MEMORY = 0x2, |
| WASM_EXTERNAL_GLOBAL = 0x3, |
| WASM_EXTERNAL_EVENT = 0x4, |
| }; |
| |
| // Opcodes used in initializer expressions. |
| enum : unsigned { |
| WASM_OPCODE_END = 0x0b, |
| WASM_OPCODE_CALL = 0x10, |
| WASM_OPCODE_GLOBAL_GET = 0x23, |
| WASM_OPCODE_I32_STORE = 0x36, |
| WASM_OPCODE_I32_CONST = 0x41, |
| WASM_OPCODE_I64_CONST = 0x42, |
| WASM_OPCODE_F32_CONST = 0x43, |
| WASM_OPCODE_F64_CONST = 0x44, |
| WASM_OPCODE_I32_ADD = 0x6a, |
| WASM_OPCODE_MISC_PREFIX = 0xfc, |
| WASM_OPCODE_MEMORY_INIT = 0x08, |
| WASM_OPCODE_DATA_DROP = 0x09, |
| }; |
| |
| enum : unsigned { |
| WASM_LIMITS_FLAG_HAS_MAX = 0x1, |
| WASM_LIMITS_FLAG_IS_SHARED = 0x2, |
| }; |
| |
| enum : unsigned { |
| WASM_SEGMENT_IS_PASSIVE = 0x01, |
| WASM_SEGMENT_HAS_MEMINDEX = 0x02, |
| }; |
| |
| // Feature policy prefixes used in the custom "target_features" section |
| enum : uint8_t { |
| WASM_FEATURE_PREFIX_USED = '+', |
| WASM_FEATURE_PREFIX_REQUIRED = '=', |
| WASM_FEATURE_PREFIX_DISALLOWED = '-', |
| }; |
| |
| // Kind codes used in the custom "name" section |
| enum : unsigned { |
| WASM_NAMES_FUNCTION = 0x1, |
| WASM_NAMES_LOCAL = 0x2, |
| }; |
| |
| // Kind codes used in the custom "linking" section |
| enum : unsigned { |
| WASM_SEGMENT_INFO = 0x5, |
| WASM_INIT_FUNCS = 0x6, |
| WASM_COMDAT_INFO = 0x7, |
| WASM_SYMBOL_TABLE = 0x8, |
| }; |
| |
| // Kind codes used in the custom "linking" section in the WASM_COMDAT_INFO |
| enum : unsigned { |
| WASM_COMDAT_DATA = 0x0, |
| WASM_COMDAT_FUNCTION = 0x1, |
| }; |
| |
| // Kind codes used in the custom "linking" section in the WASM_SYMBOL_TABLE |
| enum WasmSymbolType : unsigned { |
| WASM_SYMBOL_TYPE_FUNCTION = 0x0, |
| WASM_SYMBOL_TYPE_DATA = 0x1, |
| WASM_SYMBOL_TYPE_GLOBAL = 0x2, |
| WASM_SYMBOL_TYPE_SECTION = 0x3, |
| WASM_SYMBOL_TYPE_EVENT = 0x4, |
| }; |
| |
| // Kinds of event attributes. |
| enum WasmEventAttribute : unsigned { |
| WASM_EVENT_ATTRIBUTE_EXCEPTION = 0x0, |
| }; |
| |
| const unsigned WASM_SYMBOL_BINDING_MASK = 0x3; |
| const unsigned WASM_SYMBOL_VISIBILITY_MASK = 0xc; |
| |
| const unsigned WASM_SYMBOL_BINDING_GLOBAL = 0x0; |
| const unsigned WASM_SYMBOL_BINDING_WEAK = 0x1; |
| const unsigned WASM_SYMBOL_BINDING_LOCAL = 0x2; |
| const unsigned WASM_SYMBOL_VISIBILITY_DEFAULT = 0x0; |
| const unsigned WASM_SYMBOL_VISIBILITY_HIDDEN = 0x4; |
| const unsigned WASM_SYMBOL_UNDEFINED = 0x10; |
| const unsigned WASM_SYMBOL_EXPORTED = 0x20; |
| const unsigned WASM_SYMBOL_EXPLICIT_NAME = 0x40; |
| |
| #define WASM_RELOC(name, value) name = value, |
| |
| enum : unsigned { |
| #include "WasmRelocs.def" |
| }; |
| |
| #undef WASM_RELOC |
| |
| // Subset of types that a value can have |
| enum class ValType { |
| I32 = WASM_TYPE_I32, |
| I64 = WASM_TYPE_I64, |
| F32 = WASM_TYPE_F32, |
| F64 = WASM_TYPE_F64, |
| V128 = WASM_TYPE_V128, |
| EXCEPT_REF = WASM_TYPE_EXCEPT_REF, |
| }; |
| |
| struct WasmSignature { |
| SmallVector<ValType, 1> Returns; |
| SmallVector<ValType, 4> Params; |
| // Support empty and tombstone instances, needed by DenseMap. |
| enum { Plain, Empty, Tombstone } State = Plain; |
| |
| WasmSignature(SmallVector<ValType, 1> &&InReturns, |
| SmallVector<ValType, 4> &&InParams) |
| : Returns(InReturns), Params(InParams) {} |
| WasmSignature() = default; |
| }; |
| |
| // Useful comparison operators |
| inline bool operator==(const WasmSignature &LHS, const WasmSignature &RHS) { |
| return LHS.State == RHS.State && LHS.Returns == RHS.Returns && |
| LHS.Params == RHS.Params; |
| } |
| |
| inline bool operator!=(const WasmSignature &LHS, const WasmSignature &RHS) { |
| return !(LHS == RHS); |
| } |
| |
| inline bool operator==(const WasmGlobalType &LHS, const WasmGlobalType &RHS) { |
| return LHS.Type == RHS.Type && LHS.Mutable == RHS.Mutable; |
| } |
| |
| inline bool operator!=(const WasmGlobalType &LHS, const WasmGlobalType &RHS) { |
| return !(LHS == RHS); |
| } |
| |
| std::string toString(WasmSymbolType type); |
| std::string relocTypetoString(uint32_t type); |
| bool relocTypeHasAddend(uint32_t type); |
| |
| } // end namespace wasm |
| } // end namespace llvm |
| |
| #endif |