function _toConsumableArray(arr) { if (Array.isArray(arr)) { for (var i = 0, arr2 = new Array(arr.length); i < arr.length; i++) { arr2[i] = arr[i]; } return arr2; } else { return Array.from(arr); } } import { CompileError } from "@webassemblyjs/helper-api-error"; import * as ieee754 from "@webassemblyjs/ieee754"; import * as utf8 from "@webassemblyjs/utf8"; import * as t from "@webassemblyjs/ast"; import { decodeInt32, decodeUInt32, MAX_NUMBER_OF_BYTE_U32, decodeInt64, decodeUInt64, MAX_NUMBER_OF_BYTE_U64 } from "@webassemblyjs/leb128"; import constants from "@webassemblyjs/helper-wasm-bytecode"; function toHex(n) { return "0x" + Number(n).toString(16); } function byteArrayEq(l, r) { if (l.length !== r.length) { return false; } for (var i = 0; i < l.length; i++) { if (l[i] !== r[i]) { return false; } } return true; } export function decode(ab, opts) { var buf = new Uint8Array(ab); var getUniqueName = t.getUniqueNameGenerator(); var offset = 0; function getPosition() { return { line: -1, column: offset }; } function dump(b, msg) { if (opts.dump === false) return; var pad = "\t\t\t\t\t\t\t\t\t\t"; var str = ""; if (b.length < 5) { str = b.map(toHex).join(" "); } else { str = "..."; } console.log(toHex(offset) + ":\t", str, pad, ";", msg); } function dumpSep(msg) { if (opts.dump === false) return; console.log(";", msg); } /** * TODO(sven): we can atually use a same structure * we are adding incrementally new features */ var state = { elementsInFuncSection: [], elementsInExportSection: [], elementsInCodeSection: [], /** * Decode memory from: * - Memory section */ memoriesInModule: [], /** * Decoded types from: * - Type section */ typesInModule: [], /** * Decoded functions from: * - Function section * - Import section */ functionsInModule: [], /** * Decoded tables from: * - Table section */ tablesInModule: [], /** * Decoded globals from: * - Global section */ globalsInModule: [] }; function isEOF() { return offset >= buf.length; } function eatBytes(n) { offset = offset + n; } function readBytesAtOffset(_offset, numberOfBytes) { var arr = []; for (var i = 0; i < numberOfBytes; i++) { arr.push(buf[_offset + i]); } return arr; } function readBytes(numberOfBytes) { return readBytesAtOffset(offset, numberOfBytes); } function readF64() { var bytes = readBytes(ieee754.NUMBER_OF_BYTE_F64); var value = ieee754.decodeF64(bytes); if (Math.sign(value) * value === Infinity) { return { value: Math.sign(value), inf: true, nextIndex: ieee754.NUMBER_OF_BYTE_F64 }; } if (isNaN(value)) { var sign = bytes[bytes.length - 1] >> 7 ? -1 : 1; var mantissa = 0; for (var i = 0; i < bytes.length - 2; ++i) { mantissa += bytes[i] * Math.pow(256, i); } mantissa += bytes[bytes.length - 2] % 16 * Math.pow(256, bytes.length - 2); return { value: sign * mantissa, nan: true, nextIndex: ieee754.NUMBER_OF_BYTE_F64 }; } return { value: value, nextIndex: ieee754.NUMBER_OF_BYTE_F64 }; } function readF32() { var bytes = readBytes(ieee754.NUMBER_OF_BYTE_F32); var value = ieee754.decodeF32(bytes); if (Math.sign(value) * value === Infinity) { return { value: Math.sign(value), inf: true, nextIndex: ieee754.NUMBER_OF_BYTE_F32 }; } if (isNaN(value)) { var sign = bytes[bytes.length - 1] >> 7 ? -1 : 1; var mantissa = 0; for (var i = 0; i < bytes.length - 2; ++i) { mantissa += bytes[i] * Math.pow(256, i); } mantissa += bytes[bytes.length - 2] % 128 * Math.pow(256, bytes.length - 2); return { value: sign * mantissa, nan: true, nextIndex: ieee754.NUMBER_OF_BYTE_F32 }; } return { value: value, nextIndex: ieee754.NUMBER_OF_BYTE_F32 }; } function readUTF8String() { var lenu32 = readU32(); // Don't eat any bytes. Instead, peek ahead of the current offset using // readBytesAtOffset below. This keeps readUTF8String neutral with respect // to the current offset, just like the other readX functions. var strlen = lenu32.value; dump([strlen], "string length"); var bytes = readBytesAtOffset(offset + lenu32.nextIndex, strlen); var value = utf8.decode(bytes); return { value: value, nextIndex: strlen + lenu32.nextIndex }; } /** * Decode an unsigned 32bits integer * * The length will be handled by the leb librairy, we pass the max number of * byte. */ function readU32() { var bytes = readBytes(MAX_NUMBER_OF_BYTE_U32); var buffer = Buffer.from(bytes); return decodeUInt32(buffer); } function readVaruint32() { // where 32 bits = max 4 bytes var bytes = readBytes(4); var buffer = Buffer.from(bytes); return decodeUInt32(buffer); } function readVaruint7() { // where 7 bits = max 1 bytes var bytes = readBytes(1); var buffer = Buffer.from(bytes); return decodeUInt32(buffer); } /** * Decode a signed 32bits interger */ function read32() { var bytes = readBytes(MAX_NUMBER_OF_BYTE_U32); var buffer = Buffer.from(bytes); return decodeInt32(buffer); } /** * Decode a signed 64bits integer */ function read64() { var bytes = readBytes(MAX_NUMBER_OF_BYTE_U64); var buffer = Buffer.from(bytes); return decodeInt64(buffer); } function readU64() { var bytes = readBytes(MAX_NUMBER_OF_BYTE_U64); var buffer = Buffer.from(bytes); return decodeUInt64(buffer); } function readByte() { return readBytes(1)[0]; } function parseModuleHeader() { if (isEOF() === true || offset + 4 > buf.length) { throw new Error("unexpected end"); } var header = readBytes(4); if (byteArrayEq(constants.magicModuleHeader, header) === false) { throw new CompileError("magic header not detected"); } dump(header, "wasm magic header"); eatBytes(4); } function parseVersion() { if (isEOF() === true || offset + 4 > buf.length) { throw new Error("unexpected end"); } var version = readBytes(4); if (byteArrayEq(constants.moduleVersion, version) === false) { throw new CompileError("unknown binary version"); } dump(version, "wasm version"); eatBytes(4); } function parseVec(cast) { var u32 = readU32(); var length = u32.value; eatBytes(u32.nextIndex); dump([length], "number"); if (length === 0) { return []; } var elements = []; for (var i = 0; i < length; i++) { var byte = readByte(); eatBytes(1); var value = cast(byte); dump([byte], value); if (typeof value === "undefined") { throw new CompileError("Internal failure: parseVec could not cast the value"); } elements.push(value); } return elements; } // Type section // https://webassembly.github.io/spec/binary/modules.html#binary-typesec function parseTypeSection(numberOfTypes) { var typeInstructionNodes = []; dump([numberOfTypes], "num types"); for (var i = 0; i < numberOfTypes; i++) { var startLoc = getPosition(); dumpSep("type " + i); var type = readByte(); eatBytes(1); if (type == constants.types.func) { dump([type], "func"); var paramValtypes = parseVec(function (b) { return constants.valtypes[b]; }); var params = paramValtypes.map(function (v) { return t.funcParam( /*valtype*/ v); }); var result = parseVec(function (b) { return constants.valtypes[b]; }); var endLoc = getPosition(); typeInstructionNodes.push(t.withLoc(t.typeInstruction(undefined, t.signature(params, result)), endLoc, startLoc)); state.typesInModule.push({ params: params, result: result }); } else { throw new Error("Unsupported type: " + toHex(type)); } } return typeInstructionNodes; } // Import section // https://webassembly.github.io/spec/binary/modules.html#binary-importsec function parseImportSection(numberOfImports) { var imports = []; for (var i = 0; i < numberOfImports; i++) { dumpSep("import header " + i); var startLoc = getPosition(); /** * Module name */ var moduleName = readUTF8String(); eatBytes(moduleName.nextIndex); dump([], "module name (".concat(moduleName.value, ")")); /** * Name */ var name = readUTF8String(); eatBytes(name.nextIndex); dump([], "name (".concat(name.value, ")")); /** * Import descr */ var descrTypeByte = readByte(); eatBytes(1); var descrType = constants.importTypes[descrTypeByte]; dump([descrTypeByte], "import kind"); if (typeof descrType === "undefined") { throw new CompileError("Unknown import description type: " + toHex(descrTypeByte)); } var importDescr = void 0; if (descrType === "func") { var indexU32 = readU32(); var typeindex = indexU32.value; eatBytes(indexU32.nextIndex); dump([typeindex], "type index"); var signature = state.typesInModule[typeindex]; if (typeof signature === "undefined") { throw new CompileError("function signature not found (".concat(typeindex, ")")); } var id = getUniqueName("func"); importDescr = t.funcImportDescr(id, t.signature(signature.params, signature.result)); state.functionsInModule.push({ id: t.identifier(name.value), signature: signature, isExternal: true }); } else if (descrType === "global") { importDescr = parseGlobalType(); var globalNode = t.global(importDescr, []); state.globalsInModule.push(globalNode); } else if (descrType === "table") { importDescr = parseTableType(i); } else if (descrType === "mem") { var memoryNode = parseMemoryType(0); state.memoriesInModule.push(memoryNode); importDescr = memoryNode; } else { throw new CompileError("Unsupported import of type: " + descrType); } var endLoc = getPosition(); imports.push(t.withLoc(t.moduleImport(moduleName.value, name.value, importDescr), endLoc, startLoc)); } return imports; } // Function section // https://webassembly.github.io/spec/binary/modules.html#function-section function parseFuncSection(numberOfFunctions) { dump([numberOfFunctions], "num funcs"); for (var i = 0; i < numberOfFunctions; i++) { var indexU32 = readU32(); var typeindex = indexU32.value; eatBytes(indexU32.nextIndex); dump([typeindex], "type index"); var signature = state.typesInModule[typeindex]; if (typeof signature === "undefined") { throw new CompileError("function signature not found (".concat(typeindex, ")")); } // preserve anonymous, a name might be resolved later var id = t.withRaw(t.identifier(getUniqueName("func")), ""); state.functionsInModule.push({ id: id, signature: signature, isExternal: false }); } } // Export section // https://webassembly.github.io/spec/binary/modules.html#export-section function parseExportSection(numberOfExport) { dump([numberOfExport], "num exports"); // Parse vector of exports for (var i = 0; i < numberOfExport; i++) { var startLoc = getPosition(); /** * Name */ var name = readUTF8String(); eatBytes(name.nextIndex); dump([], "export name (".concat(name.value, ")")); /** * exportdescr */ var typeIndex = readByte(); eatBytes(1); dump([typeIndex], "export kind"); var indexu32 = readU32(); var index = indexu32.value; eatBytes(indexu32.nextIndex); dump([index], "export index"); var id = void 0, signature = void 0; if (constants.exportTypes[typeIndex] === "Func") { var func = state.functionsInModule[index]; if (typeof func === "undefined") { throw new CompileError("entry not found at index ".concat(index, " in function section")); } id = t.numberLiteralFromRaw(index, String(index)); signature = func.signature; } else if (constants.exportTypes[typeIndex] === "Table") { var table = state.tablesInModule[index]; if (typeof table === "undefined") { throw new CompileError("entry not found at index ".concat(index, " in table section")); } id = t.numberLiteralFromRaw(index, String(index)); signature = null; } else if (constants.exportTypes[typeIndex] === "Mem") { var memNode = state.memoriesInModule[index]; if (typeof memNode === "undefined") { throw new CompileError("entry not found at index ".concat(index, " in memory section")); } id = t.numberLiteralFromRaw(index, String(index)); signature = null; } else if (constants.exportTypes[typeIndex] === "Global") { var global = state.globalsInModule[index]; if (typeof global === "undefined") { throw new CompileError("entry not found at index ".concat(index, " in global section")); } id = t.numberLiteralFromRaw(index, String(index)); signature = null; } else { console.warn("Unsupported export type: " + toHex(typeIndex)); return; } var endLoc = getPosition(); state.elementsInExportSection.push({ name: name.value, type: constants.exportTypes[typeIndex], signature: signature, id: id, index: index, endLoc: endLoc, startLoc: startLoc }); } } // Code section // https://webassembly.github.io/spec/binary/modules.html#code-section function parseCodeSection(numberOfFuncs) { dump([numberOfFuncs], "number functions"); // Parse vector of function for (var i = 0; i < numberOfFuncs; i++) { var startLoc = getPosition(); dumpSep("function body " + i); // the u32 size of the function code in bytes // Ignore it for now var bodySizeU32 = readU32(); eatBytes(bodySizeU32.nextIndex); dump([bodySizeU32.value], "function body size"); var code = []; /** * Parse locals */ var funcLocalNumU32 = readU32(); var funcLocalNum = funcLocalNumU32.value; eatBytes(funcLocalNumU32.nextIndex); dump([funcLocalNum], "num locals"); var locals = []; for (var _i = 0; _i < funcLocalNum; _i++) { var localCountU32 = readU32(); var localCount = localCountU32.value; eatBytes(localCountU32.nextIndex); dump([localCount], "num local"); var valtypeByte = readByte(); eatBytes(1); var type = constants.valtypes[valtypeByte]; locals.push(type); dump([valtypeByte], type); if (typeof type === "undefined") { throw new CompileError("Unexpected valtype: " + toHex(valtypeByte)); } } // Decode instructions until the end parseInstructionBlock(code); code.unshift.apply(code, _toConsumableArray(locals.map(function (l) { return t.instruction("local", [t.valtypeLiteral(l)]); }))); var endLoc = getPosition(); state.elementsInCodeSection.push({ code: code, locals: locals, endLoc: endLoc, startLoc: startLoc, bodySize: bodySizeU32.value }); } } function parseInstructionBlock(code) { while (true) { var startLoc = getPosition(); var instructionAlreadyCreated = false; var instructionByte = readByte(); eatBytes(1); if (instructionByte === 0xfe) { throw new CompileError("Atomic instructions are not implemented"); } var instruction = constants.symbolsByByte[instructionByte]; if (typeof instruction === "undefined") { throw new CompileError("Unexpected instruction: " + toHex(instructionByte)); } if (typeof instruction.object === "string") { dump([instructionByte], "".concat(instruction.object, ".").concat(instruction.name)); } else { dump([instructionByte], instruction.name); } /** * End of the function */ if (instruction.name === "end") { break; } var args = []; if (instruction.name === "loop") { var blocktypeByte = readByte(); eatBytes(1); var blocktype = constants.blockTypes[blocktypeByte]; dump([blocktypeByte], "blocktype"); if (typeof blocktype === "undefined") { throw new CompileError("Unexpected blocktype: " + toHex(blocktypeByte)); } var instr = []; parseInstructionBlock(instr); // preserve anonymous var label = t.withRaw(t.identifier(getUniqueName("loop")), ""); var loopNode = t.loopInstruction(label, blocktype, instr); code.push(loopNode); instructionAlreadyCreated = true; } else if (instruction.name === "if") { var _blocktypeByte = readByte(); eatBytes(1); var _blocktype = constants.blockTypes[_blocktypeByte]; dump([_blocktypeByte], "blocktype"); if (typeof _blocktype === "undefined") { throw new CompileError("Unexpected blocktype: " + toHex(_blocktypeByte)); } var testIndex = t.withRaw(t.identifier(getUniqueName("if")), ""); var ifBody = []; parseInstructionBlock(ifBody); // Defaults to no alternate var elseIndex = 0; for (elseIndex = 0; elseIndex < ifBody.length; ++elseIndex) { var _instr = ifBody[elseIndex]; if (_instr.type === "Instr" && _instr.id === "else") { break; } } var consequentInstr = ifBody.slice(0, elseIndex); var alternate = ifBody.slice(elseIndex + 1); // wast sugar var testInstrs = []; var ifNode = t.ifInstruction(testIndex, testInstrs, _blocktype, consequentInstr, alternate); code.push(ifNode); instructionAlreadyCreated = true; } else if (instruction.name === "block") { var _blocktypeByte2 = readByte(); eatBytes(1); var _blocktype2 = constants.blockTypes[_blocktypeByte2]; dump([_blocktypeByte2], "blocktype"); if (typeof _blocktype2 === "undefined") { throw new CompileError("Unexpected blocktype: " + toHex(_blocktypeByte2)); } var _instr2 = []; parseInstructionBlock(_instr2); // preserve anonymous var _label = t.withRaw(t.identifier(getUniqueName("block")), ""); var blockNode = t.blockInstruction(_label, _instr2, _blocktype2); code.push(blockNode); instructionAlreadyCreated = true; } else if (instruction.name === "call") { var indexu32 = readU32(); var index = indexu32.value; eatBytes(indexu32.nextIndex); dump([index], "index"); var callNode = t.callInstruction(t.indexLiteral(index)); code.push(callNode); instructionAlreadyCreated = true; } else if (instruction.name === "call_indirect") { var indexU32 = readU32(); var typeindex = indexU32.value; eatBytes(indexU32.nextIndex); dump([typeindex], "type index"); var signature = state.typesInModule[typeindex]; if (typeof signature === "undefined") { throw new CompileError("call_indirect signature not found (".concat(typeindex, ")")); } var _callNode = t.callIndirectInstruction(t.signature(signature.params, signature.result), []); var flagU32 = readU32(); var flag = flagU32.value; // 0x00 - reserved byte eatBytes(flagU32.nextIndex); if (flag !== 0) { throw new CompileError("zero flag expected"); } code.push(_callNode); instructionAlreadyCreated = true; } else if (instruction.name === "br_table") { var indicesu32 = readU32(); var indices = indicesu32.value; eatBytes(indicesu32.nextIndex); dump([indices], "num indices"); for (var i = 0; i <= indices; i++) { var _indexu = readU32(); var _index = _indexu.value; eatBytes(_indexu.nextIndex); dump([_index], "index"); args.push(t.numberLiteralFromRaw(_indexu.value.toString(), "u32")); } } else if (instructionByte >= 0x28 && instructionByte <= 0x40) { /** * Memory instructions */ if (instruction.name === "grow_memory" || instruction.name === "current_memory") { var _indexU = readU32(); var _index2 = _indexU.value; eatBytes(_indexU.nextIndex); if (_index2 !== 0) { throw new Error("zero flag expected"); } dump([_index2], "index"); } else { var aligun32 = readU32(); var align = aligun32.value; eatBytes(aligun32.nextIndex); dump([align], "align"); var offsetu32 = readU32(); var _offset2 = offsetu32.value; eatBytes(offsetu32.nextIndex); dump([_offset2], "offset"); } } else if (instructionByte >= 0x41 && instructionByte <= 0x44) { /** * Numeric instructions */ if (instruction.object === "i32") { var value32 = read32(); var value = value32.value; eatBytes(value32.nextIndex); dump([value], "i32 value"); args.push(t.numberLiteralFromRaw(value)); } if (instruction.object === "u32") { var valueu32 = readU32(); var _value = valueu32.value; eatBytes(valueu32.nextIndex); dump([_value], "u32 value"); args.push(t.numberLiteralFromRaw(_value)); } if (instruction.object === "i64") { var value64 = read64(); var _value2 = value64.value; eatBytes(value64.nextIndex); dump([Number(_value2.toString())], "i64 value"); var high = _value2.high, low = _value2.low; var node = { type: "LongNumberLiteral", value: { high: high, low: low } }; args.push(node); } if (instruction.object === "u64") { var valueu64 = readU64(); var _value3 = valueu64.value; eatBytes(valueu64.nextIndex); dump([Number(_value3.toString())], "u64 value"); var _high = _value3.high, _low = _value3.low; var _node = { type: "LongNumberLiteral", value: { high: _high, low: _low } }; args.push(_node); } if (instruction.object === "f32") { var valuef32 = readF32(); var _value4 = valuef32.value; eatBytes(valuef32.nextIndex); dump([_value4], "f32 value"); args.push( // $FlowIgnore t.floatLiteral(_value4, valuef32.nan, valuef32.inf, String(_value4))); } if (instruction.object === "f64") { var valuef64 = readF64(); var _value5 = valuef64.value; eatBytes(valuef64.nextIndex); dump([_value5], "f64 value"); args.push( // $FlowIgnore t.floatLiteral(_value5, valuef64.nan, valuef64.inf, String(_value5))); } } else { for (var _i2 = 0; _i2 < instruction.numberOfArgs; _i2++) { var u32 = readU32(); eatBytes(u32.nextIndex); dump([u32.value], "argument " + _i2); args.push(t.numberLiteralFromRaw(u32.value)); } } if (instructionAlreadyCreated === false) { if (typeof instruction.object === "string") { code.push(t.objectInstruction(instruction.name, instruction.object, args)); } else { var endLoc = getPosition(); var _node2 = t.withLoc(t.instruction(instruction.name, args), endLoc, startLoc); code.push(_node2); } } } } // https://webassembly.github.io/spec/core/binary/types.html#limits function parseLimits() { var limitType = readByte(); eatBytes(1); dump([limitType], "limit type"); var min, max; if (limitType === 0x01 || limitType === 0x03 // shared limits ) { var u32min = readU32(); min = parseInt(u32min.value); eatBytes(u32min.nextIndex); dump([min], "min"); var u32max = readU32(); max = parseInt(u32max.value); eatBytes(u32max.nextIndex); dump([max], "max"); } if (limitType === 0x00) { var _u32min = readU32(); min = parseInt(_u32min.value); eatBytes(_u32min.nextIndex); dump([min], "min"); } return t.limit(min, max); } // https://webassembly.github.io/spec/core/binary/types.html#binary-tabletype function parseTableType(index) { var name = t.withRaw(t.identifier(getUniqueName("table")), String(index)); var elementTypeByte = readByte(); eatBytes(1); dump([elementTypeByte], "element type"); var elementType = constants.tableTypes[elementTypeByte]; if (typeof elementType === "undefined") { throw new CompileError("Unknown element type in table: " + toHex(elementType)); } var limits = parseLimits(); return t.table(elementType, limits, name); } // https://webassembly.github.io/spec/binary/types.html#global-types function parseGlobalType() { var valtypeByte = readByte(); eatBytes(1); var type = constants.valtypes[valtypeByte]; dump([valtypeByte], type); if (typeof type === "undefined") { throw new CompileError("Unknown valtype: " + toHex(valtypeByte)); } var globalTypeByte = readByte(); eatBytes(1); var globalType = constants.globalTypes[globalTypeByte]; dump([globalTypeByte], "global type (".concat(globalType, ")")); if (typeof globalType === "undefined") { throw new CompileError("Invalid mutability: " + toHex(globalTypeByte)); } return t.globalType(type, globalType); } // function parseNameModule() { // const lenu32 = readVaruint32(); // eatBytes(lenu32.nextIndex); // console.log("len", lenu32); // const strlen = lenu32.value; // dump([strlen], "string length"); // const bytes = readBytes(strlen); // eatBytes(strlen); // const value = utf8.decode(bytes); // return [t.moduleNameMetadata(value)]; // } // this section contains an array of function names and indices function parseNameSectionFunctions() { var functionNames = []; var numberOfFunctionsu32 = readU32(); var numbeOfFunctions = numberOfFunctionsu32.value; eatBytes(numberOfFunctionsu32.nextIndex); for (var i = 0; i < numbeOfFunctions; i++) { var indexu32 = readU32(); var index = indexu32.value; eatBytes(indexu32.nextIndex); var name = readUTF8String(); eatBytes(name.nextIndex); functionNames.push(t.functionNameMetadata(name.value, index)); } return functionNames; } function parseNameSectionLocals() { var localNames = []; var numbeOfFunctionsu32 = readU32(); var numbeOfFunctions = numbeOfFunctionsu32.value; eatBytes(numbeOfFunctionsu32.nextIndex); for (var i = 0; i < numbeOfFunctions; i++) { var functionIndexu32 = readU32(); var functionIndex = functionIndexu32.value; eatBytes(functionIndexu32.nextIndex); var numLocalsu32 = readU32(); var numLocals = numLocalsu32.value; eatBytes(numLocalsu32.nextIndex); for (var _i3 = 0; _i3 < numLocals; _i3++) { var localIndexu32 = readU32(); var localIndex = localIndexu32.value; eatBytes(localIndexu32.nextIndex); var name = readUTF8String(); eatBytes(name.nextIndex); localNames.push(t.localNameMetadata(name.value, localIndex, functionIndex)); } } return localNames; } // this is a custom section used for name resolution // https://github.com/WebAssembly/design/blob/master/BinaryEncoding.md#name-section function parseNameSection(remainingBytes) { var nameMetadata = []; var initialOffset = offset; while (offset - initialOffset < remainingBytes) { // name_type var sectionTypeByte = readVaruint7(); eatBytes(sectionTypeByte.nextIndex); // name_payload_len var subSectionSizeInBytesu32 = readVaruint32(); eatBytes(subSectionSizeInBytesu32.nextIndex); switch (sectionTypeByte.value) { // case 0: { // TODO(sven): re-enable that // Current status: it seems that when we decode the module's name // no name_payload_len is used. // // See https://github.com/WebAssembly/design/blob/master/BinaryEncoding.md#name-section // // nameMetadata.push(...parseNameModule()); // break; // } case 1: { nameMetadata.push.apply(nameMetadata, _toConsumableArray(parseNameSectionFunctions())); break; } case 2: { nameMetadata.push.apply(nameMetadata, _toConsumableArray(parseNameSectionLocals())); break; } default: { // skip unknown subsection eatBytes(subSectionSizeInBytesu32.value); } } } return nameMetadata; } function parseGlobalSection(numberOfGlobals) { var globals = []; dump([numberOfGlobals], "num globals"); for (var i = 0; i < numberOfGlobals; i++) { var startLoc = getPosition(); var globalType = parseGlobalType(); /** * Global expressions */ var init = []; parseInstructionBlock(init); var endLoc = getPosition(); var node = t.withLoc(t.global(globalType, init), endLoc, startLoc); globals.push(node); state.globalsInModule.push(node); } return globals; } function parseElemSection(numberOfElements) { var elems = []; dump([numberOfElements], "num elements"); for (var i = 0; i < numberOfElements; i++) { var startLoc = getPosition(); var tableindexu32 = readU32(); var tableindex = tableindexu32.value; eatBytes(tableindexu32.nextIndex); dump([tableindex], "table index"); /** * Parse instructions */ var instr = []; parseInstructionBlock(instr); /** * Parse ( vector function index ) * */ var indicesu32 = readU32(); var indices = indicesu32.value; eatBytes(indicesu32.nextIndex); dump([indices], "num indices"); var indexValues = []; for (var _i4 = 0; _i4 < indices; _i4++) { var indexu32 = readU32(); var index = indexu32.value; eatBytes(indexu32.nextIndex); dump([index], "index"); indexValues.push(t.indexLiteral(index)); } var endLoc = getPosition(); var elemNode = t.withLoc(t.elem(t.indexLiteral(tableindex), instr, indexValues), endLoc, startLoc); elems.push(elemNode); } return elems; } // https://webassembly.github.io/spec/core/binary/types.html#memory-types function parseMemoryType(i) { var limits = parseLimits(); return t.memory(limits, t.indexLiteral(i)); } // https://webassembly.github.io/spec/binary/modules.html#table-section function parseTableSection(numberOfElements) { var tables = []; dump([numberOfElements], "num elements"); for (var i = 0; i < numberOfElements; i++) { var tablesNode = parseTableType(i); state.tablesInModule.push(tablesNode); tables.push(tablesNode); } return tables; } // https://webassembly.github.io/spec/binary/modules.html#memory-section function parseMemorySection(numberOfElements) { var memories = []; dump([numberOfElements], "num elements"); for (var i = 0; i < numberOfElements; i++) { var memoryNode = parseMemoryType(i); state.memoriesInModule.push(memoryNode); memories.push(memoryNode); } return memories; } // https://webassembly.github.io/spec/binary/modules.html#binary-startsec function parseStartSection() { var startLoc = getPosition(); var u32 = readU32(); var startFuncIndex = u32.value; eatBytes(u32.nextIndex); dump([startFuncIndex], "index"); var endLoc = getPosition(); return t.withLoc(t.start(t.indexLiteral(startFuncIndex)), endLoc, startLoc); } // https://webassembly.github.io/spec/binary/modules.html#data-section function parseDataSection(numberOfElements) { var dataEntries = []; dump([numberOfElements], "num elements"); for (var i = 0; i < numberOfElements; i++) { var memoryIndexu32 = readU32(); var memoryIndex = memoryIndexu32.value; eatBytes(memoryIndexu32.nextIndex); dump([memoryIndex], "memory index"); var instrs = []; parseInstructionBlock(instrs); if (instrs.length !== 1) { throw new CompileError("data section offset must be a single instruction"); } var bytes = parseVec(function (b) { return b; }); dump([], "init"); dataEntries.push(t.data(t.memIndexLiteral(memoryIndex), instrs[0], t.byteArray(bytes))); } return dataEntries; } // https://webassembly.github.io/spec/binary/modules.html#binary-section function parseSection(sectionIndex) { var sectionId = readByte(); eatBytes(1); if (sectionId >= sectionIndex || sectionIndex === constants.sections.custom) { sectionIndex = sectionId + 1; } else { if (sectionId !== constants.sections.custom) throw new CompileError("Unexpected section: " + toHex(sectionId)); } var nextSectionIndex = sectionIndex; var startOffset = offset; var startPosition = getPosition(); var u32 = readU32(); var sectionSizeInBytes = u32.value; eatBytes(u32.nextIndex); var sectionSizeInBytesEndLoc = getPosition(); var sectionSizeInBytesNode = t.withLoc(t.numberLiteralFromRaw(sectionSizeInBytes), sectionSizeInBytesEndLoc, startPosition); switch (sectionId) { case constants.sections.type: { dumpSep("section Type"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _startPosition = getPosition(); var _u = readU32(); var numberOfTypes = _u.value; eatBytes(_u.nextIndex); var endPosition = getPosition(); var _metadata = t.sectionMetadata("type", startOffset, sectionSizeInBytesNode, t.withLoc(t.numberLiteralFromRaw(numberOfTypes), endPosition, _startPosition)); var _nodes = parseTypeSection(numberOfTypes); return { nodes: _nodes, metadata: _metadata, nextSectionIndex: nextSectionIndex }; } case constants.sections.table: { dumpSep("section Table"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _startPosition2 = getPosition(); var _u2 = readU32(); var numberOfTable = _u2.value; eatBytes(_u2.nextIndex); var _endPosition = getPosition(); dump([numberOfTable], "num tables"); var _metadata2 = t.sectionMetadata("table", startOffset, sectionSizeInBytesNode, t.withLoc(t.numberLiteralFromRaw(numberOfTable), _endPosition, _startPosition2)); var _nodes2 = parseTableSection(numberOfTable); return { nodes: _nodes2, metadata: _metadata2, nextSectionIndex: nextSectionIndex }; } case constants.sections.import: { dumpSep("section Import"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _startPosition3 = getPosition(); var numberOfImportsu32 = readU32(); var numberOfImports = numberOfImportsu32.value; eatBytes(numberOfImportsu32.nextIndex); var _endPosition2 = getPosition(); dump([numberOfImports], "number of imports"); var _metadata3 = t.sectionMetadata("import", startOffset, sectionSizeInBytesNode, t.withLoc(t.numberLiteralFromRaw(numberOfImports), _endPosition2, _startPosition3)); var _nodes3 = parseImportSection(numberOfImports); return { nodes: _nodes3, metadata: _metadata3, nextSectionIndex: nextSectionIndex }; } case constants.sections.func: { dumpSep("section Function"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _startPosition4 = getPosition(); var numberOfFunctionsu32 = readU32(); var numberOfFunctions = numberOfFunctionsu32.value; eatBytes(numberOfFunctionsu32.nextIndex); var _endPosition3 = getPosition(); var _metadata4 = t.sectionMetadata("func", startOffset, sectionSizeInBytesNode, t.withLoc(t.numberLiteralFromRaw(numberOfFunctions), _endPosition3, _startPosition4)); parseFuncSection(numberOfFunctions); var _nodes4 = []; return { nodes: _nodes4, metadata: _metadata4, nextSectionIndex: nextSectionIndex }; } case constants.sections.export: { dumpSep("section Export"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _startPosition5 = getPosition(); var _u3 = readU32(); var numberOfExport = _u3.value; eatBytes(_u3.nextIndex); var _endPosition4 = getPosition(); var _metadata5 = t.sectionMetadata("export", startOffset, sectionSizeInBytesNode, t.withLoc(t.numberLiteralFromRaw(numberOfExport), _endPosition4, _startPosition5)); parseExportSection(numberOfExport); var _nodes5 = []; return { nodes: _nodes5, metadata: _metadata5, nextSectionIndex: nextSectionIndex }; } case constants.sections.code: { dumpSep("section Code"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _startPosition6 = getPosition(); var _u4 = readU32(); var numberOfFuncs = _u4.value; eatBytes(_u4.nextIndex); var _endPosition5 = getPosition(); var _metadata6 = t.sectionMetadata("code", startOffset, sectionSizeInBytesNode, t.withLoc(t.numberLiteralFromRaw(numberOfFuncs), _endPosition5, _startPosition6)); if (opts.ignoreCodeSection === true) { var remainingBytes = sectionSizeInBytes - _u4.nextIndex; eatBytes(remainingBytes); // eat the entire section } else { parseCodeSection(numberOfFuncs); } var _nodes6 = []; return { nodes: _nodes6, metadata: _metadata6, nextSectionIndex: nextSectionIndex }; } case constants.sections.start: { dumpSep("section Start"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _metadata7 = t.sectionMetadata("start", startOffset, sectionSizeInBytesNode); var _nodes7 = [parseStartSection()]; return { nodes: _nodes7, metadata: _metadata7, nextSectionIndex: nextSectionIndex }; } case constants.sections.element: { dumpSep("section Element"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _startPosition7 = getPosition(); var numberOfElementsu32 = readU32(); var numberOfElements = numberOfElementsu32.value; eatBytes(numberOfElementsu32.nextIndex); var _endPosition6 = getPosition(); var _metadata8 = t.sectionMetadata("element", startOffset, sectionSizeInBytesNode, t.withLoc(t.numberLiteralFromRaw(numberOfElements), _endPosition6, _startPosition7)); var _nodes8 = parseElemSection(numberOfElements); return { nodes: _nodes8, metadata: _metadata8, nextSectionIndex: nextSectionIndex }; } case constants.sections.global: { dumpSep("section Global"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _startPosition8 = getPosition(); var numberOfGlobalsu32 = readU32(); var numberOfGlobals = numberOfGlobalsu32.value; eatBytes(numberOfGlobalsu32.nextIndex); var _endPosition7 = getPosition(); var _metadata9 = t.sectionMetadata("global", startOffset, sectionSizeInBytesNode, t.withLoc(t.numberLiteralFromRaw(numberOfGlobals), _endPosition7, _startPosition8)); var _nodes9 = parseGlobalSection(numberOfGlobals); return { nodes: _nodes9, metadata: _metadata9, nextSectionIndex: nextSectionIndex }; } case constants.sections.memory: { dumpSep("section Memory"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _startPosition9 = getPosition(); var _numberOfElementsu = readU32(); var _numberOfElements = _numberOfElementsu.value; eatBytes(_numberOfElementsu.nextIndex); var _endPosition8 = getPosition(); var _metadata10 = t.sectionMetadata("memory", startOffset, sectionSizeInBytesNode, t.withLoc(t.numberLiteralFromRaw(_numberOfElements), _endPosition8, _startPosition9)); var _nodes10 = parseMemorySection(_numberOfElements); return { nodes: _nodes10, metadata: _metadata10, nextSectionIndex: nextSectionIndex }; } case constants.sections.data: { dumpSep("section Data"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _metadata11 = t.sectionMetadata("data", startOffset, sectionSizeInBytesNode); var _startPosition10 = getPosition(); var _numberOfElementsu2 = readU32(); var _numberOfElements2 = _numberOfElementsu2.value; eatBytes(_numberOfElementsu2.nextIndex); var _endPosition9 = getPosition(); _metadata11.vectorOfSize = t.withLoc(t.numberLiteralFromRaw(_numberOfElements2), _endPosition9, _startPosition10); if (opts.ignoreDataSection === true) { var _remainingBytes = sectionSizeInBytes - _numberOfElementsu2.nextIndex; eatBytes(_remainingBytes); // eat the entire section dumpSep("ignore data (" + sectionSizeInBytes + " bytes)"); return { nodes: [], metadata: _metadata11, nextSectionIndex: nextSectionIndex }; } else { var _nodes11 = parseDataSection(_numberOfElements2); return { nodes: _nodes11, metadata: _metadata11, nextSectionIndex: nextSectionIndex }; } } case constants.sections.custom: { dumpSep("section Custom"); dump([sectionId], "section code"); dump([sectionSizeInBytes], "section size"); var _metadata12 = [t.sectionMetadata("custom", startOffset, sectionSizeInBytesNode)]; var sectionName = readUTF8String(); eatBytes(sectionName.nextIndex); dump([], "section name (".concat(sectionName.value, ")")); var _remainingBytes2 = sectionSizeInBytes - sectionName.nextIndex; if (sectionName.value === "name") { try { _metadata12.push.apply(_metadata12, _toConsumableArray(parseNameSection(_remainingBytes2))); } catch (e) { console.warn("Failed to decode custom \"name\" section @".concat(offset, "; ignoring (").concat(e.message, ").")); eatBytes(_remainingBytes2); } } else { // We don't parse the custom section eatBytes(_remainingBytes2); dumpSep("ignore custom " + JSON.stringify(sectionName.value) + " section (" + _remainingBytes2 + " bytes)"); } return { nodes: [], metadata: _metadata12, nextSectionIndex: nextSectionIndex }; } } throw new CompileError("Unexpected section: " + toHex(sectionId)); } parseModuleHeader(); parseVersion(); var moduleFields = []; var sectionIndex = 0; var moduleMetadata = { sections: [], functionNames: [], localNames: [] }; /** * All the generate declaration are going to be stored in our state */ while (offset < buf.length) { var _parseSection = parseSection(sectionIndex), _nodes12 = _parseSection.nodes, _metadata13 = _parseSection.metadata, nextSectionIndex = _parseSection.nextSectionIndex; moduleFields.push.apply(moduleFields, _toConsumableArray(_nodes12)); var metadataArray = Array.isArray(_metadata13) ? _metadata13 : [_metadata13]; metadataArray.forEach(function (metadataItem) { if (metadataItem.type === "FunctionNameMetadata") { moduleMetadata.functionNames.push(metadataItem); } else if (metadataItem.type === "LocalNameMetadata") { moduleMetadata.localNames.push(metadataItem); } else { moduleMetadata.sections.push(metadataItem); } }); // Ignore custom section if (nextSectionIndex) { sectionIndex = nextSectionIndex; } } /** * Transform the state into AST nodes */ var funcIndex = 0; state.functionsInModule.forEach(function (func) { var params = func.signature.params; var result = func.signature.result; var body = []; // External functions doesn't provide any code, can skip it here if (func.isExternal === true) { return; } var decodedElementInCodeSection = state.elementsInCodeSection[funcIndex]; if (opts.ignoreCodeSection === false) { if (typeof decodedElementInCodeSection === "undefined") { throw new CompileError("func " + toHex(funcIndex) + " code not found"); } body = decodedElementInCodeSection.code; } funcIndex++; var funcNode = t.func(func.id, t.signature(params, result), body); if (func.isExternal === true) { funcNode.isExternal = func.isExternal; } // Add function position in the binary if possible if (opts.ignoreCodeSection === false) { var startLoc = decodedElementInCodeSection.startLoc, endLoc = decodedElementInCodeSection.endLoc, bodySize = decodedElementInCodeSection.bodySize; funcNode = t.withLoc(funcNode, endLoc, startLoc); funcNode.metadata = { bodySize: bodySize }; } moduleFields.push(funcNode); }); state.elementsInExportSection.forEach(function (moduleExport) { /** * If the export has no id, we won't be able to call it from the outside * so we can omit it */ if (moduleExport.id != null) { moduleFields.push(t.withLoc(t.moduleExport(moduleExport.name, t.moduleExportDescr(moduleExport.type, moduleExport.id)), moduleExport.endLoc, moduleExport.startLoc)); } }); dumpSep("end of program"); var module = t.module(null, moduleFields, t.moduleMetadata(moduleMetadata.sections, moduleMetadata.functionNames, moduleMetadata.localNames)); return t.program([module]); }