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// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Used for encoding f32 and double constants to bits.
let byte_view = new Uint8Array(8);
let data_view = new DataView(byte_view.buffer);
// The bytes function receives one of
// - several arguments, each of which is either a number or a string of length
// 1; if it's a string, the charcode of the contained character is used.
// - a single array argument containing the actual arguments
// - a single string; the returned buffer will contain the char codes of all
// contained characters.
function bytes(...input) {
if (input.length == 1 && typeof input[0] == 'array') input = input[0];
if (input.length == 1 && typeof input[0] == 'string') {
let len = input[0].length;
let view = new Uint8Array(len);
for (let i = 0; i < len; i++) view[i] = input[0].charCodeAt(i);
return view.buffer;
}
let view = new Uint8Array(input.length);
for (let i = 0; i < input.length; i++) {
let val = input[i];
if (typeof val == 'string') {
assertEquals(1, val.length, 'string inputs must have length 1');
val = val.charCodeAt(0);
}
view[i] = val | 0;
}
return view.buffer;
}
// Header declaration constants
var kWasmH0 = 0;
var kWasmH1 = 0x61;
var kWasmH2 = 0x73;
var kWasmH3 = 0x6d;
var kWasmV0 = 0x1;
var kWasmV1 = 0;
var kWasmV2 = 0;
var kWasmV3 = 0;
var kHeaderSize = 8;
var kPageSize = 65536;
var kSpecMaxPages = 65535;
var kMaxVarInt32Size = 5;
var kMaxVarInt64Size = 10;
let kDeclNoLocals = 0;
// Section declaration constants
let kUnknownSectionCode = 0;
let kTypeSectionCode = 1; // Function signature declarations
let kImportSectionCode = 2; // Import declarations
let kFunctionSectionCode = 3; // Function declarations
let kTableSectionCode = 4; // Indirect function table and other tables
let kMemorySectionCode = 5; // Memory attributes
let kGlobalSectionCode = 6; // Global declarations
let kExportSectionCode = 7; // Exports
let kStartSectionCode = 8; // Start function declaration
let kElementSectionCode = 9; // Elements section
let kCodeSectionCode = 10; // Function code
let kDataSectionCode = 11; // Data segments
let kDataCountSectionCode = 12; // Data segment count (between Element & Code)
let kTagSectionCode = 13; // Tag section (between Memory & Global)
// Name section types
let kModuleNameCode = 0;
let kFunctionNamesCode = 1;
let kLocalNamesCode = 2;
let kWasmFunctionTypeForm = 0x60;
let kWasmAnyFunctionTypeForm = 0x70;
let kWasmStructTypeForm = 0x5f;
let kWasmArrayTypeForm = 0x5e;
let kWasmSubtypeForm = 0x50;
let kWasmSubtypeFinalForm = 0x4f;
let kWasmRecursiveTypeGroupForm = 0x4e;
let kNoSuperType = 0xFFFFFFFF;
let kHasMaximumFlag = 1;
let kSharedHasMaximumFlag = 3;
// Segment flags
let kActiveNoIndex = 0;
let kPassive = 1;
let kActiveWithIndex = 2;
let kPassiveWithElements = 5;
// Function declaration flags
let kDeclFunctionName = 0x01;
let kDeclFunctionImport = 0x02;
let kDeclFunctionLocals = 0x04;
let kDeclFunctionExport = 0x08;
// Local types
let kWasmStmt = 0x40;
let kWasmI32 = 0x7f;
let kWasmI64 = 0x7e;
let kWasmF32 = 0x7d;
let kWasmF64 = 0x7c;
let kWasmS128 = 0x7b;
// These are defined as negative integers to distinguish them from positive type
// indices.
let kWasmNullFuncRef = -0x0d;
let kWasmNullExternRef = -0x0e;
let kWasmNullRef = -0x0f;
let kWasmFuncRef = -0x10;
let kWasmAnyFunc = kWasmFuncRef; // Alias named as in the JS API spec
let kWasmExternRef = -0x11;
let kWasmAnyRef = -0x12;
let kWasmEqRef = -0x13;
let kWasmI31Ref = -0x14;
let kWasmStructRef = -0x15;
let kWasmArrayRef = -0x16;
// Use the positive-byte versions inside function bodies.
let kLeb128Mask = 0x7f;
let kFuncRefCode = kWasmFuncRef & kLeb128Mask;
let kAnyFuncCode = kFuncRefCode; // Alias named as in the JS API spec
let kExternRefCode = kWasmExternRef & kLeb128Mask;
let kAnyRefCode = kWasmAnyRef & kLeb128Mask;
let kEqRefCode = kWasmEqRef & kLeb128Mask;
let kI31RefCode = kWasmI31Ref & kLeb128Mask;
let kNullExternRefCode = kWasmNullExternRef & kLeb128Mask;
let kNullFuncRefCode = kWasmNullFuncRef & kLeb128Mask;
let kStructRefCode = kWasmStructRef & kLeb128Mask;
let kArrayRefCode = kWasmArrayRef & kLeb128Mask;
let kNullRefCode = kWasmNullRef & kLeb128Mask;
let kWasmRefNull = 0x63;
let kWasmRef = 0x64;
function wasmRefNullType(heap_type) {
return {opcode: kWasmRefNull, heap_type: heap_type};
}
function wasmRefType(heap_type) {
return {opcode: kWasmRef, heap_type: heap_type};
}
let kExternalFunction = 0;
let kExternalTable = 1;
let kExternalMemory = 2;
let kExternalGlobal = 3;
let kExternalTag = 4;
let kTableZero = 0;
let kMemoryZero = 0;
let kSegmentZero = 0;
let kTagAttribute = 0;
// Useful signatures
let kSig_i_i = makeSig([kWasmI32], [kWasmI32]);
let kSig_l_l = makeSig([kWasmI64], [kWasmI64]);
let kSig_i_l = makeSig([kWasmI64], [kWasmI32]);
let kSig_i_ii = makeSig([kWasmI32, kWasmI32], [kWasmI32]);
let kSig_i_iii = makeSig([kWasmI32, kWasmI32, kWasmI32], [kWasmI32]);
let kSig_v_iiii = makeSig([kWasmI32, kWasmI32, kWasmI32, kWasmI32], []);
let kSig_f_ff = makeSig([kWasmF32, kWasmF32], [kWasmF32]);
let kSig_d_dd = makeSig([kWasmF64, kWasmF64], [kWasmF64]);
let kSig_l_ll = makeSig([kWasmI64, kWasmI64], [kWasmI64]);
let kSig_i_dd = makeSig([kWasmF64, kWasmF64], [kWasmI32]);
let kSig_v_v = makeSig([], []);
let kSig_i_v = makeSig([], [kWasmI32]);
let kSig_l_v = makeSig([], [kWasmI64]);
let kSig_f_v = makeSig([], [kWasmF32]);
let kSig_d_v = makeSig([], [kWasmF64]);
let kSig_v_i = makeSig([kWasmI32], []);
let kSig_v_ii = makeSig([kWasmI32, kWasmI32], []);
let kSig_v_iii = makeSig([kWasmI32, kWasmI32, kWasmI32], []);
let kSig_v_l = makeSig([kWasmI64], []);
let kSig_v_d = makeSig([kWasmF64], []);
let kSig_v_dd = makeSig([kWasmF64, kWasmF64], []);
let kSig_v_ddi = makeSig([kWasmF64, kWasmF64, kWasmI32], []);
let kSig_ii_v = makeSig([], [kWasmI32, kWasmI32]);
let kSig_iii_v = makeSig([], [kWasmI32, kWasmI32, kWasmI32]);
let kSig_ii_i = makeSig([kWasmI32], [kWasmI32, kWasmI32]);
let kSig_iii_i = makeSig([kWasmI32], [kWasmI32, kWasmI32, kWasmI32]);
let kSig_ii_ii = makeSig([kWasmI32, kWasmI32], [kWasmI32, kWasmI32]);
let kSig_iii_ii = makeSig([kWasmI32, kWasmI32], [kWasmI32, kWasmI32, kWasmI32]);
let kSig_v_f = makeSig([kWasmF32], []);
let kSig_f_f = makeSig([kWasmF32], [kWasmF32]);
let kSig_f_d = makeSig([kWasmF64], [kWasmF32]);
let kSig_d_d = makeSig([kWasmF64], [kWasmF64]);
let kSig_r_r = makeSig([kWasmExternRef], [kWasmExternRef]);
let kSig_a_a = makeSig([kWasmAnyFunc], [kWasmAnyFunc]);
let kSig_i_r = makeSig([kWasmExternRef], [kWasmI32]);
let kSig_v_r = makeSig([kWasmExternRef], []);
let kSig_v_a = makeSig([kWasmAnyFunc], []);
let kSig_v_rr = makeSig([kWasmExternRef, kWasmExternRef], []);
let kSig_v_aa = makeSig([kWasmAnyFunc, kWasmAnyFunc], []);
let kSig_r_v = makeSig([], [kWasmExternRef]);
let kSig_a_v = makeSig([], [kWasmAnyFunc]);
let kSig_a_i = makeSig([kWasmI32], [kWasmAnyFunc]);
function makeSig(params, results) {
return {params: params, results: results};
}
function makeSig_v_x(x) {
return makeSig([x], []);
}
function makeSig_v_xx(x) {
return makeSig([x, x], []);
}
function makeSig_r_v(r) {
return makeSig([], [r]);
}
function makeSig_r_x(r, x) {
return makeSig([x], [r]);
}
function makeSig_r_xx(r, x) {
return makeSig([x, x], [r]);
}
// Opcodes
let kExprUnreachable = 0x00;
let kExprNop = 0x01;
let kExprBlock = 0x02;
let kExprLoop = 0x03;
let kExprIf = 0x04;
let kExprElse = 0x05;
let kExprTry = 0x06;
let kExprCatch = 0x07;
let kExprCatchAll = 0x19;
let kExprThrow = 0x08;
let kExprRethrow = 0x09;
let kExprBrOnExn = 0x0a;
let kExprEnd = 0x0b;
let kExprBr = 0x0c;
let kExprBrIf = 0x0d;
let kExprBrTable = 0x0e;
let kExprReturn = 0x0f;
let kExprCallFunction = 0x10;
let kExprCallIndirect = 0x11;
let kExprReturnCall = 0x12;
let kExprReturnCallIndirect = 0x13;
let kExprDrop = 0x1a;
let kExprSelect = 0x1b;
let kExprLocalGet = 0x20;
let kExprLocalSet = 0x21;
let kExprLocalTee = 0x22;
let kExprGlobalGet = 0x23;
let kExprGlobalSet = 0x24;
let kExprTableGet = 0x25;
let kExprTableSet = 0x26;
let kExprI32LoadMem = 0x28;
let kExprI64LoadMem = 0x29;
let kExprF32LoadMem = 0x2a;
let kExprF64LoadMem = 0x2b;
let kExprI32LoadMem8S = 0x2c;
let kExprI32LoadMem8U = 0x2d;
let kExprI32LoadMem16S = 0x2e;
let kExprI32LoadMem16U = 0x2f;
let kExprI64LoadMem8S = 0x30;
let kExprI64LoadMem8U = 0x31;
let kExprI64LoadMem16S = 0x32;
let kExprI64LoadMem16U = 0x33;
let kExprI64LoadMem32S = 0x34;
let kExprI64LoadMem32U = 0x35;
let kExprI32StoreMem = 0x36;
let kExprI64StoreMem = 0x37;
let kExprF32StoreMem = 0x38;
let kExprF64StoreMem = 0x39;
let kExprI32StoreMem8 = 0x3a;
let kExprI32StoreMem16 = 0x3b;
let kExprI64StoreMem8 = 0x3c;
let kExprI64StoreMem16 = 0x3d;
let kExprI64StoreMem32 = 0x3e;
let kExprMemorySize = 0x3f;
let kExprMemoryGrow = 0x40;
let kExprI32Const = 0x41;
let kExprI64Const = 0x42;
let kExprF32Const = 0x43;
let kExprF64Const = 0x44;
let kExprI32Eqz = 0x45;
let kExprI32Eq = 0x46;
let kExprI32Ne = 0x47;
let kExprI32LtS = 0x48;
let kExprI32LtU = 0x49;
let kExprI32GtS = 0x4a;
let kExprI32GtU = 0x4b;
let kExprI32LeS = 0x4c;
let kExprI32LeU = 0x4d;
let kExprI32GeS = 0x4e;
let kExprI32GeU = 0x4f;
let kExprI64Eqz = 0x50;
let kExprI64Eq = 0x51;
let kExprI64Ne = 0x52;
let kExprI64LtS = 0x53;
let kExprI64LtU = 0x54;
let kExprI64GtS = 0x55;
let kExprI64GtU = 0x56;
let kExprI64LeS = 0x57;
let kExprI64LeU = 0x58;
let kExprI64GeS = 0x59;
let kExprI64GeU = 0x5a;
let kExprF32Eq = 0x5b;
let kExprF32Ne = 0x5c;
let kExprF32Lt = 0x5d;
let kExprF32Gt = 0x5e;
let kExprF32Le = 0x5f;
let kExprF32Ge = 0x60;
let kExprF64Eq = 0x61;
let kExprF64Ne = 0x62;
let kExprF64Lt = 0x63;
let kExprF64Gt = 0x64;
let kExprF64Le = 0x65;
let kExprF64Ge = 0x66;
let kExprI32Clz = 0x67;
let kExprI32Ctz = 0x68;
let kExprI32Popcnt = 0x69;
let kExprI32Add = 0x6a;
let kExprI32Sub = 0x6b;
let kExprI32Mul = 0x6c;
let kExprI32DivS = 0x6d;
let kExprI32DivU = 0x6e;
let kExprI32RemS = 0x6f;
let kExprI32RemU = 0x70;
let kExprI32And = 0x71;
let kExprI32Ior = 0x72;
let kExprI32Xor = 0x73;
let kExprI32Shl = 0x74;
let kExprI32ShrS = 0x75;
let kExprI32ShrU = 0x76;
let kExprI32Rol = 0x77;
let kExprI32Ror = 0x78;
let kExprI64Clz = 0x79;
let kExprI64Ctz = 0x7a;
let kExprI64Popcnt = 0x7b;
let kExprI64Add = 0x7c;
let kExprI64Sub = 0x7d;
let kExprI64Mul = 0x7e;
let kExprI64DivS = 0x7f;
let kExprI64DivU = 0x80;
let kExprI64RemS = 0x81;
let kExprI64RemU = 0x82;
let kExprI64And = 0x83;
let kExprI64Ior = 0x84;
let kExprI64Xor = 0x85;
let kExprI64Shl = 0x86;
let kExprI64ShrS = 0x87;
let kExprI64ShrU = 0x88;
let kExprI64Rol = 0x89;
let kExprI64Ror = 0x8a;
let kExprF32Abs = 0x8b;
let kExprF32Neg = 0x8c;
let kExprF32Ceil = 0x8d;
let kExprF32Floor = 0x8e;
let kExprF32Trunc = 0x8f;
let kExprF32NearestInt = 0x90;
let kExprF32Sqrt = 0x91;
let kExprF32Add = 0x92;
let kExprF32Sub = 0x93;
let kExprF32Mul = 0x94;
let kExprF32Div = 0x95;
let kExprF32Min = 0x96;
let kExprF32Max = 0x97;
let kExprF32CopySign = 0x98;
let kExprF64Abs = 0x99;
let kExprF64Neg = 0x9a;
let kExprF64Ceil = 0x9b;
let kExprF64Floor = 0x9c;
let kExprF64Trunc = 0x9d;
let kExprF64NearestInt = 0x9e;
let kExprF64Sqrt = 0x9f;
let kExprF64Add = 0xa0;
let kExprF64Sub = 0xa1;
let kExprF64Mul = 0xa2;
let kExprF64Div = 0xa3;
let kExprF64Min = 0xa4;
let kExprF64Max = 0xa5;
let kExprF64CopySign = 0xa6;
let kExprI32ConvertI64 = 0xa7;
let kExprI32SConvertF32 = 0xa8;
let kExprI32UConvertF32 = 0xa9;
let kExprI32SConvertF64 = 0xaa;
let kExprI32UConvertF64 = 0xab;
let kExprI64SConvertI32 = 0xac;
let kExprI64UConvertI32 = 0xad;
let kExprI64SConvertF32 = 0xae;
let kExprI64UConvertF32 = 0xaf;
let kExprI64SConvertF64 = 0xb0;
let kExprI64UConvertF64 = 0xb1;
let kExprF32SConvertI32 = 0xb2;
let kExprF32UConvertI32 = 0xb3;
let kExprF32SConvertI64 = 0xb4;
let kExprF32UConvertI64 = 0xb5;
let kExprF32ConvertF64 = 0xb6;
let kExprF64SConvertI32 = 0xb7;
let kExprF64UConvertI32 = 0xb8;
let kExprF64SConvertI64 = 0xb9;
let kExprF64UConvertI64 = 0xba;
let kExprF64ConvertF32 = 0xbb;
let kExprI32ReinterpretF32 = 0xbc;
let kExprI64ReinterpretF64 = 0xbd;
let kExprF32ReinterpretI32 = 0xbe;
let kExprF64ReinterpretI64 = 0xbf;
let kExprI32SExtendI8 = 0xc0;
let kExprI32SExtendI16 = 0xc1;
let kExprI64SExtendI8 = 0xc2;
let kExprI64SExtendI16 = 0xc3;
let kExprI64SExtendI32 = 0xc4;
let kExprRefNull = 0xd0;
let kExprRefIsNull = 0xd1;
let kExprRefFunc = 0xd2;
// Prefix opcodes
let kGCPrefix = 0xfb;
let kNumericPrefix = 0xfc;
let kSimdPrefix = 0xfd;
let kAtomicPrefix = 0xfe;
// Use these for multi-byte instructions (opcode > 0x7F needing two LEB bytes):
function GCInstr(opcode) {
if (opcode <= 0x7F) return [kGCPrefix, opcode];
return [kGCPrefix, 0x80 | (opcode & 0x7F), opcode >> 7];
}
// GC opcodes
let kExprStructNew = 0x00;
let kExprStructNewDefault = 0x01;
let kExprStructGet = 0x02;
let kExprStructGetS = 0x03;
let kExprStructGetU = 0x04;
let kExprStructSet = 0x05;
let kExprArrayNew = 0x06;
let kExprArrayNewDefault = 0x07;
let kExprArrayNewFixed = 0x08;
let kExprArrayNewData = 0x09;
let kExprArrayNewElem = 0x0a;
let kExprArrayGet = 0x0b;
let kExprArrayGetS = 0x0c;
let kExprArrayGetU = 0x0d;
let kExprArraySet = 0x0e;
let kExprArrayLen = 0x0f;
let kExprArrayFill = 0x10;
let kExprArrayCopy = 0x11;
let kExprArrayInitData = 0x12;
let kExprArrayInitElem = 0x13;
let kExprRefTest = 0x14;
let kExprRefTestNull = 0x15;
let kExprRefCast = 0x16;
let kExprRefCastNull = 0x17;
let kExprBrOnCast = 0x18;
let kExprBrOnCastFail = 0x19;
let kExprExternInternalize = 0x1a;
let kExprExternExternalize = 0x1b;
let kExprI31New = 0x1c;
let kExprI31GetS = 0x1d;
let kExprI31GetU = 0x1e;
// Numeric opcodes.
let kExprMemoryInit = 0x08;
let kExprDataDrop = 0x09;
let kExprMemoryCopy = 0x0a;
let kExprMemoryFill = 0x0b;
let kExprTableInit = 0x0c;
let kExprElemDrop = 0x0d;
let kExprTableCopy = 0x0e;
let kExprTableGrow = 0x0f;
let kExprTableSize = 0x10;
let kExprTableFill = 0x11;
// Atomic opcodes.
let kExprAtomicNotify = 0x00;
let kExprI32AtomicWait = 0x01;
let kExprI64AtomicWait = 0x02;
let kExprI32AtomicLoad = 0x10;
let kExprI32AtomicLoad8U = 0x12;
let kExprI32AtomicLoad16U = 0x13;
let kExprI32AtomicStore = 0x17;
let kExprI32AtomicStore8U = 0x19;
let kExprI32AtomicStore16U = 0x1a;
let kExprI32AtomicAdd = 0x1e;
let kExprI32AtomicAdd8U = 0x20;
let kExprI32AtomicAdd16U = 0x21;
let kExprI32AtomicSub = 0x25;
let kExprI32AtomicSub8U = 0x27;
let kExprI32AtomicSub16U = 0x28;
let kExprI32AtomicAnd = 0x2c;
let kExprI32AtomicAnd8U = 0x2e;
let kExprI32AtomicAnd16U = 0x2f;
let kExprI32AtomicOr = 0x33;
let kExprI32AtomicOr8U = 0x35;
let kExprI32AtomicOr16U = 0x36;
let kExprI32AtomicXor = 0x3a;
let kExprI32AtomicXor8U = 0x3c;
let kExprI32AtomicXor16U = 0x3d;
let kExprI32AtomicExchange = 0x41;
let kExprI32AtomicExchange8U = 0x43;
let kExprI32AtomicExchange16U = 0x44;
let kExprI32AtomicCompareExchange = 0x48;
let kExprI32AtomicCompareExchange8U = 0x4a;
let kExprI32AtomicCompareExchange16U = 0x4b;
let kExprI64AtomicLoad = 0x11;
let kExprI64AtomicLoad8U = 0x14;
let kExprI64AtomicLoad16U = 0x15;
let kExprI64AtomicLoad32U = 0x16;
let kExprI64AtomicStore = 0x18;
let kExprI64AtomicStore8U = 0x1b;
let kExprI64AtomicStore16U = 0x1c;
let kExprI64AtomicStore32U = 0x1d;
let kExprI64AtomicAdd = 0x1f;
let kExprI64AtomicAdd8U = 0x22;
let kExprI64AtomicAdd16U = 0x23;
let kExprI64AtomicAdd32U = 0x24;
let kExprI64AtomicSub = 0x26;
let kExprI64AtomicSub8U = 0x29;
let kExprI64AtomicSub16U = 0x2a;
let kExprI64AtomicSub32U = 0x2b;
let kExprI64AtomicAnd = 0x2d;
let kExprI64AtomicAnd8U = 0x30;
let kExprI64AtomicAnd16U = 0x31;
let kExprI64AtomicAnd32U = 0x32;
let kExprI64AtomicOr = 0x34;
let kExprI64AtomicOr8U = 0x37;
let kExprI64AtomicOr16U = 0x38;
let kExprI64AtomicOr32U = 0x39;
let kExprI64AtomicXor = 0x3b;
let kExprI64AtomicXor8U = 0x3e;
let kExprI64AtomicXor16U = 0x3f;
let kExprI64AtomicXor32U = 0x40;
let kExprI64AtomicExchange = 0x42;
let kExprI64AtomicExchange8U = 0x45;
let kExprI64AtomicExchange16U = 0x46;
let kExprI64AtomicExchange32U = 0x47;
let kExprI64AtomicCompareExchange = 0x49
let kExprI64AtomicCompareExchange8U = 0x4c;
let kExprI64AtomicCompareExchange16U = 0x4d;
let kExprI64AtomicCompareExchange32U = 0x4e;
// Simd opcodes.
let kExprS128LoadMem = 0x00;
let kExprS128StoreMem = 0x01;
let kExprI32x4Splat = 0x0c;
let kExprI32x4Eq = 0x2c;
let kExprS1x4AllTrue = 0x75;
let kExprF32x4Min = 0x9e;
class Binary {
constructor() {
this.length = 0;
this.buffer = new Uint8Array(8192);
}
ensure_space(needed) {
if (this.buffer.length - this.length >= needed) return;
let new_capacity = this.buffer.length * 2;
while (new_capacity - this.length < needed) new_capacity *= 2;
let new_buffer = new Uint8Array(new_capacity);
new_buffer.set(this.buffer);
this.buffer = new_buffer;
}
trunc_buffer() {
return new Uint8Array(this.buffer.buffer, 0, this.length);
}
reset() {
this.length = 0;
}
emit_u8(val) {
this.ensure_space(1);
this.buffer[this.length++] = val;
}
emit_u16(val) {
this.ensure_space(2);
this.buffer[this.length++] = val;
this.buffer[this.length++] = val >> 8;
}
emit_u32(val) {
this.ensure_space(4);
this.buffer[this.length++] = val;
this.buffer[this.length++] = val >> 8;
this.buffer[this.length++] = val >> 16;
this.buffer[this.length++] = val >> 24;
}
emit_leb_u(val, max_len) {
this.ensure_space(max_len);
for (let i = 0; i < max_len; ++i) {
let v = val & 0xff;
val = val >>> 7;
if (val == 0) {
this.buffer[this.length++] = v;
return;
}
this.buffer[this.length++] = v | 0x80;
}
throw new Error("Leb value exceeds maximum length of " + max_len);
}
emit_u32v(val) {
this.emit_leb_u(val, kMaxVarInt32Size);
}
emit_u64v(val) {
this.emit_leb_u(val, kMaxVarInt64Size);
}
emit_bytes(data) {
this.ensure_space(data.length);
this.buffer.set(data, this.length);
this.length += data.length;
}
emit_string(string) {
// When testing illegal names, we pass a byte array directly.
if (string instanceof Array) {
this.emit_u32v(string.length);
this.emit_bytes(string);
return;
}
// This is the hacky way to convert a JavaScript string to a UTF8 encoded
// string only containing single-byte characters.
let string_utf8 = unescape(encodeURIComponent(string));
this.emit_u32v(string_utf8.length);
for (let i = 0; i < string_utf8.length; i++) {
this.emit_u8(string_utf8.charCodeAt(i));
}
}
emit_heap_type(heap_type) {
this.emit_bytes(wasmSignedLeb(heap_type, kMaxVarInt32Size));
}
emit_type(type) {
if ((typeof type) == 'number') {
this.emit_u8(type >= 0 ? type : type & kLeb128Mask);
} else {
this.emit_u8(type.opcode);
if ('depth' in type) this.emit_u8(type.depth);
this.emit_heap_type(type.heap_type);
}
}
emit_init_expr(expr) {
this.emit_bytes(expr);
this.emit_u8(kExprEnd);
}
emit_header() {
this.emit_bytes([
kWasmH0, kWasmH1, kWasmH2, kWasmH3, kWasmV0, kWasmV1, kWasmV2, kWasmV3
]);
}
emit_section(section_code, content_generator) {
// Emit section name.
this.emit_u8(section_code);
// Emit the section to a temporary buffer: its full length isn't know yet.
const section = new Binary;
content_generator(section);
// Emit section length.
this.emit_u32v(section.length);
// Copy the temporary buffer.
// Avoid spread because {section} can be huge.
this.emit_bytes(section.trunc_buffer());
}
}
class WasmFunctionBuilder {
constructor(module, name, type_index) {
this.module = module;
this.name = name;
this.type_index = type_index;
this.body = [];
this.locals = [];
this.local_names = [];
}
numLocalNames() {
let num_local_names = 0;
for (let loc_name of this.local_names) {
if (loc_name !== undefined) ++num_local_names;
}
return num_local_names;
}
exportAs(name) {
this.module.addExport(name, this.index);
return this;
}
exportFunc() {
this.exportAs(this.name);
return this;
}
addBody(body) {
for (let b of body) {
if (typeof b !== 'number' || (b & (~0xFF)) !== 0 )
throw new Error('invalid body (entries must be 8 bit numbers): ' + body);
}
this.body = body.slice();
// Automatically add the end for the function block to the body.
this.body.push(kExprEnd);
return this;
}
addBodyWithEnd(body) {
this.body = body;
return this;
}
getNumLocals() {
let total_locals = 0;
for (let l of this.locals) {
for (let type of ["i32", "i64", "f32", "f64", "s128"]) {
total_locals += l[type + "_count"] || 0;
}
}
return total_locals;
}
addLocals(locals, names) {
const old_num_locals = this.getNumLocals();
this.locals.push(locals);
if (names) {
const missing_names = old_num_locals - this.local_names.length;
this.local_names.push(...new Array(missing_names), ...names);
}
return this;
}
end() {
return this.module;
}
}
class WasmGlobalBuilder {
constructor(module, type, mutable, init) {
this.module = module;
this.type = type;
this.mutable = mutable;
this.init = init;
}
exportAs(name) {
this.module.exports.push({name: name, kind: kExternalGlobal,
index: this.index});
return this;
}
}
function checkExpr(expr) {
for (let b of expr) {
if (typeof b !== 'number' || (b & (~0xFF)) !== 0) {
throw new Error(
'invalid body (entries must be 8 bit numbers): ' + expr);
}
}
}
class WasmTableBuilder {
constructor(module, type, initial_size, max_size, init_expr) {
this.module = module;
this.type = type;
this.initial_size = initial_size;
this.has_max = max_size != undefined;
this.max_size = max_size;
this.init_expr = init_expr;
this.has_init = init_expr !== undefined;
}
exportAs(name) {
this.module.exports.push({name: name, kind: kExternalTable,
index: this.index});
return this;
}
}
function makeField(type, mutability) {
if ((typeof mutability) != 'boolean') {
throw new Error('field mutability must be boolean');
}
return {type: type, mutability: mutability};
}
class WasmStruct {
constructor(fields, is_final, supertype_idx) {
if (!Array.isArray(fields)) {
throw new Error('struct fields must be an array');
}
this.fields = fields;
this.type_form = kWasmStructTypeForm;
this.is_final = is_final;
this.supertype = supertype_idx;
}
}
class WasmArray {
constructor(type, mutability, is_final, supertype_idx) {
this.type = type;
this.mutability = mutability;
this.type_form = kWasmArrayTypeForm;
this.is_final = is_final;
this.supertype = supertype_idx;
}
}
class WasmModuleBuilder {
constructor() {
this.types = [];
this.imports = [];
this.exports = [];
this.globals = [];
this.tables = [];
this.tags = [];
this.functions = [];
this.element_segments = [];
this.data_segments = [];
this.explicit = [];
this.rec_groups = [];
this.num_imported_funcs = 0;
this.num_imported_globals = 0;
this.num_imported_tables = 0;
this.num_imported_tags = 0;
return this;
}
addStart(start_index) {
this.start_index = start_index;
return this;
}
addMemory(min, max, exp, shared) {
this.memory = {min: min, max: max, exp: exp, shared: shared};
return this;
}
addExplicitSection(bytes) {
this.explicit.push(bytes);
return this;
}
stringToBytes(name) {
var result = new Binary();
result.emit_string(name);
return result.trunc_buffer()
}
createCustomSection(name, bytes) {
name = this.stringToBytes(name);
var section = new Binary();
section.emit_u8(kUnknownSectionCode);
section.emit_u32v(name.length + bytes.length);
section.emit_bytes(name);
section.emit_bytes(bytes);
return section.trunc_buffer();
}
addCustomSection(name, bytes) {
this.explicit.push(this.createCustomSection(name, bytes));
}
// We use {is_final = true} so that the MVP syntax is generated for
// signatures.
addType(type, supertype_idx = kNoSuperType, is_final = true) {
var pl = type.params.length; // should have params
var rl = type.results.length; // should have results
var type_copy = {params: type.params, results: type.results,
is_final: is_final, supertype: supertype_idx};
this.types.push(type_copy);
return this.types.length - 1;
}
addStruct(fields, supertype_idx = kNoSuperType, is_final = false) {
this.types.push(new WasmStruct(fields, is_final, supertype_idx));
return this.types.length - 1;
}
addArray(type, mutability, supertype_idx = kNoSuperType, is_final = false) {
this.types.push(new WasmArray(type, mutability, is_final, supertype_idx));
return this.types.length - 1;
}
static defaultFor(type) {
switch (type) {
case kWasmI32:
return wasmI32Const(0);
case kWasmI64:
return wasmI64Const(0);
case kWasmF32:
return wasmF32Const(0.0);
case kWasmF64:
return wasmF64Const(0.0);
case kWasmS128:
return [kSimdPrefix, kExprS128Const, ...(new Array(16).fill(0))];
default:
if ((typeof type) != 'number' && type.opcode != kWasmRefNull) {
throw new Error("Non-defaultable type");
}
let heap_type = (typeof type) == 'number' ? type : type.heap_type;
return [kExprRefNull, ...wasmSignedLeb(heap_type, kMaxVarInt32Size)];
}
}
addGlobal(type, mutable, init) {
if (init === undefined) init = WasmModuleBuilder.defaultFor(type);
checkExpr(init);
let glob = new WasmGlobalBuilder(this, type, mutable, init);
glob.index = this.globals.length + this.num_imported_globals;
this.globals.push(glob);
return glob;
}
addTable(type, initial_size, max_size = undefined, init_expr = undefined) {
if (type == kWasmI32 || type == kWasmI64 || type == kWasmF32 ||
type == kWasmF64 || type == kWasmS128 || type == kWasmStmt) {
throw new Error('Tables must be of a reference type');
}
if (init_expr != undefined) checkExpr(init_expr);
let table = new WasmTableBuilder(
this, type, initial_size, max_size, init_expr);
table.index = this.tables.length + this.num_imported_tables;
this.tables.push(table);
return table;
}
addTag(type) {
let type_index = (typeof type) == "number" ? type : this.addType(type);
let tag_index = this.tags.length + this.num_imported_tags;
this.tags.push(type_index);
return tag_index;
}
addFunction(name, type) {
let type_index = (typeof type) == "number" ? type : this.addType(type);
let func = new WasmFunctionBuilder(this, name, type_index);
func.index = this.functions.length + this.num_imported_funcs;
this.functions.push(func);
return func;
}
addImport(module, name, type) {
if (this.functions.length != 0) {
throw new Error('Imported functions must be declared before local ones');
}
let type_index = (typeof type) == "number" ? type : this.addType(type);
this.imports.push({module: module, name: name, kind: kExternalFunction,
type: type_index});
return this.num_imported_funcs++;
}
addImportedGlobal(module, name, type, mutable = false) {
if (this.globals.length != 0) {
throw new Error('Imported globals must be declared before local ones');
}
let o = {module: module, name: name, kind: kExternalGlobal, type: type,
mutable: mutable};
this.imports.push(o);
return this.num_imported_globals++;
}
addImportedMemory(module, name, initial = 0, maximum, shared) {
let o = {module: module, name: name, kind: kExternalMemory,
initial: initial, maximum: maximum, shared: shared};
this.imports.push(o);
return this;
}
addImportedTable(module, name, initial, maximum, type) {
if (this.tables.length != 0) {
throw new Error('Imported tables must be declared before local ones');
}
let o = {module: module, name: name, kind: kExternalTable, initial: initial,
maximum: maximum, type: type || kWasmAnyFunctionTypeForm};
this.imports.push(o);
return this.num_imported_tables++;
}
addImportedTag(module, name, type) {
if (this.tags.length != 0) {
throw new Error('Imported tags must be declared before local ones');
}
let type_index = (typeof type) == "number" ? type : this.addType(type);
let o = {module: module, name: name, kind: kExternalTag, type: type_index};
this.imports.push(o);
return this.num_imported_tags++;
}
addExport(name, index) {
this.exports.push({name: name, kind: kExternalFunction, index: index});
return this;
}
addExportOfKind(name, kind, index) {
this.exports.push({name: name, kind: kind, index: index});
return this;
}
addDataSegment(addr, data, is_global = false) {
this.data_segments.push(
{addr: addr, data: data, is_global: is_global, is_active: true});
return this.data_segments.length - 1;
}
addPassiveDataSegment(data) {
this.data_segments.push({data: data, is_active: false});
return this.data_segments.length - 1;
}
exportMemoryAs(name) {
this.exports.push({name: name, kind: kExternalMemory, index: 0});
}
addElementSegment(table, base, is_global, array) {
this.element_segments.push({table: table, base: base, is_global: is_global,
array: array, is_active: true});
return this;
}
addPassiveElementSegment(array, is_import = false) {
this.element_segments.push({array: array, is_active: false});
return this;
}
appendToTable(array) {
for (let n of array) {
if (typeof n != 'number')
throw new Error('invalid table (entries have to be numbers): ' + array);
}
if (this.tables.length == 0) {
this.addTable(kWasmAnyFunc, 0);
}
// Adjust the table to the correct size.
let table = this.tables[0];
const base = table.initial_size;
const table_size = base + array.length;
table.initial_size = table_size;
if (table.has_max && table_size > table.max_size) {
table.max_size = table_size;
}
return this.addElementSegment(0, base, false, array);
}
setTableBounds(min, max = undefined) {
if (this.tables.length != 0) {
throw new Error("The table bounds of table '0' have already been set.");
}
this.addTable(kWasmAnyFunc, min, max);
return this;
}
startRecGroup() {
this.rec_groups.push({start: this.types.length, size: 0});
}
endRecGroup() {
if (this.rec_groups.length == 0) {
throw new Error("Did not start a recursive group before ending one")
}
let last_element = this.rec_groups[this.rec_groups.length - 1]
if (last_element.size != 0) {
throw new Error("Did not start a recursive group before ending one")
}
last_element.size = this.types.length - last_element.start;
}
setName(name) {
this.name = name;
return this;
}
toBuffer(debug = false) {
let binary = new Binary;
let wasm = this;
// Add header
binary.emit_header();
// Add type section
if (wasm.types.length > 0) {
if (debug) print('emitting types @ ' + binary.length);
binary.emit_section(kTypeSectionCode, section => {
let length_with_groups = wasm.types.length;
for (let group of wasm.rec_groups) {
length_with_groups -= group.size - 1;
}
section.emit_u32v(length_with_groups);
let rec_group_index = 0;
for (let i = 0; i < wasm.types.length; i++) {
if (rec_group_index < wasm.rec_groups.length &&
wasm.rec_groups[rec_group_index].start == i) {
section.emit_u8(kWasmRecursiveTypeGroupForm);
section.emit_u32v(wasm.rec_groups[rec_group_index].size);
rec_group_index++;
}
let type = wasm.types[i];
if (type.supertype != kNoSuperType) {
section.emit_u8(type.is_final ? kWasmSubtypeFinalForm
: kWasmSubtypeForm);
section.emit_u8(1); // supertype count
section.emit_u32v(type.supertype);
} else if (!type.is_final) {
section.emit_u8(kWasmSubtypeForm);
section.emit_u8(0); // no supertypes
}
if (type instanceof WasmStruct) {
section.emit_u8(kWasmStructTypeForm);
section.emit_u32v(type.fields.length);
for (let field of type.fields) {
section.emit_type(field.type);
section.emit_u8(field.mutability ? 1 : 0);
}
} else if (type instanceof WasmArray) {
section.emit_u8(kWasmArrayTypeForm);
section.emit_type(type.type);
section.emit_u8(type.mutability ? 1 : 0);
} else {
section.emit_u8(kWasmFunctionTypeForm);
section.emit_u32v(type.params.length);
for (let param of type.params) {
section.emit_type(param);
}
section.emit_u32v(type.results.length);
for (let result of type.results) {
section.emit_type(result);
}
}
}
});
}
// Add imports section
if (wasm.imports.length > 0) {
if (debug) print("emitting imports @ " + binary.length);
binary.emit_section(kImportSectionCode, section => {
section.emit_u32v(wasm.imports.length);
for (let imp of wasm.imports) {
section.emit_string(imp.module);
section.emit_string(imp.name || '');
section.emit_u8(imp.kind);
if (imp.kind == kExternalFunction) {
section.emit_u32v(imp.type_index);
} else if (imp.kind == kExternalGlobal) {
section.emit_type(imp.type);
section.emit_u8(imp.mutable);
} else if (imp.kind == kExternalMemory) {
var has_max = (typeof imp.maximum) != "undefined";
var is_shared = (typeof imp.shared) != "undefined";
if (is_shared) {
section.emit_u8(has_max ? 3 : 2); // flags
} else {
section.emit_u8(has_max ? 1 : 0); // flags
}
section.emit_u32v(imp.initial); // initial
if (has_max) section.emit_u32v(imp.maximum); // maximum
} else if (imp.kind == kExternalTable) {
section.emit_type(imp.type);
var has_max = (typeof imp.maximum) != "undefined";
section.emit_u8(has_max ? 1 : 0); // flags
section.emit_u32v(imp.initial); // initial
if (has_max) section.emit_u32v(imp.maximum); // maximum
} else if (imp.kind == kExternalTag) {
section.emit_u32v(kTagAttribute);
section.emit_u32v(imp.type);
} else {
throw new Error("unknown/unsupported import kind " + imp.kind);
}
}
});
}
// Add functions declarations
if (wasm.functions.length > 0) {
if (debug) print("emitting function decls @ " + binary.length);
binary.emit_section(kFunctionSectionCode, section => {
section.emit_u32v(wasm.functions.length);
for (let func of wasm.functions) {
section.emit_u32v(func.type_index);
}
});
}
// Add table section
if (wasm.tables.length > 0) {
if (debug) print ("emitting tables @ " + binary.length);
binary.emit_section(kTableSectionCode, section => {
section.emit_u32v(wasm.tables.length);
for (let table of wasm.tables) {
section.emit_type(table.type);
section.emit_u8(table.has_max);
section.emit_u32v(table.initial_size);
if (table.has_max) section.emit_u32v(table.max_size);
if (table.has_init) section.emit_init_expr(table.init_expr);
}
});
}
// Add memory section
if (wasm.memory !== undefined) {
if (debug) print("emitting memory @ " + binary.length);
binary.emit_section(kMemorySectionCode, section => {
section.emit_u8(1); // one memory entry
const has_max = wasm.memory.max !== undefined;
const is_shared = wasm.memory.shared !== undefined;
// Emit flags (bit 0: reszeable max, bit 1: shared memory)
if (is_shared) {
section.emit_u8(has_max ? kSharedHasMaximumFlag : 2);
} else {
section.emit_u8(has_max ? kHasMaximumFlag : 0);
}
section.emit_u32v(wasm.memory.min);
if (has_max) section.emit_u32v(wasm.memory.max);
});
}
// Add global section.
if (wasm.globals.length > 0) {
if (debug) print ("emitting globals @ " + binary.length);
binary.emit_section(kGlobalSectionCode, section => {
section.emit_u32v(wasm.globals.length);
for (let global of wasm.globals) {
section.emit_type(global.type);
section.emit_u8(global.mutable);
section.emit_init_expr(global.init);
}
});
}
// Add tags.
if (wasm.tags.length > 0) {
if (debug) print("emitting tags @ " + binary.length);
binary.emit_section(kTagSectionCode, section => {
section.emit_u32v(wasm.tags.length);
for (let type of wasm.tags) {
section.emit_u32v(kTagAttribute);
section.emit_u32v(type);
}
});
}
// Add export table.
var mem_export = (wasm.memory !== undefined && wasm.memory.exp);
var exports_count = wasm.exports.length + (mem_export ? 1 : 0);
if (exports_count > 0) {
if (debug) print("emitting exports @ " + binary.length);
binary.emit_section(kExportSectionCode, section => {
section.emit_u32v(exports_count);
for (let exp of wasm.exports) {
section.emit_string(exp.name);
section.emit_u8(exp.kind);
section.emit_u32v(exp.index);
}
if (mem_export) {
section.emit_string("memory");
section.emit_u8(kExternalMemory);
section.emit_u8(0);
}
});
}
// Add start function section.
if (wasm.start_index !== undefined) {
if (debug) print("emitting start function @ " + binary.length);
binary.emit_section(kStartSectionCode, section => {
section.emit_u32v(wasm.start_index);
});
}
// Add element segments
if (wasm.element_segments.length > 0) {
if (debug) print("emitting element segments @ " + binary.length);
binary.emit_section(kElementSectionCode, section => {
var inits = wasm.element_segments;
section.emit_u32v(inits.length);
for (let init of inits) {
if (init.is_active) {
// Active segment.
if (init.table == 0) {
section.emit_u32v(kActiveNoIndex);
} else {
section.emit_u32v(kActiveWithIndex);
section.emit_u32v(init.table);
}
if (init.is_global) {
section.emit_u8(kExprGlobalGet);
} else {
section.emit_u8(kExprI32Const);
}
section.emit_u32v(init.base);
section.emit_u8(kExprEnd);
if (init.table != 0) {
section.emit_u8(kExternalFunction);
}
section.emit_u32v(init.array.length);
for (let index of init.array) {
section.emit_u32v(index);
}
} else {
// Passive segment.
section.emit_u8(kPassiveWithElements); // flags
section.emit_u8(kWasmAnyFunc);
section.emit_u32v(init.array.length);
for (let index of init.array) {
if (index === null) {
section.emit_u8(kExprRefNull);
section.emit_u8(kExprEnd);
} else {
section.emit_u8(kExprRefFunc);
section.emit_u32v(index);
section.emit_u8(kExprEnd);
}
}
}
}
});
}
// If there are any passive data segments, add the DataCount section.
if (wasm.data_segments.some(seg => !seg.is_active)) {
binary.emit_section(kDataCountSectionCode, section => {
section.emit_u32v(wasm.data_segments.length);
});
}
// Add function bodies.
if (wasm.functions.length > 0) {
// emit function bodies
if (debug) print("emitting code @ " + binary.length);
binary.emit_section(kCodeSectionCode, section => {
section.emit_u32v(wasm.functions.length);
let header = new Binary;
for (let func of wasm.functions) {
header.reset();
// Function body length will be patched later.
let local_decls = [];
for (let l of func.locals || []) {
if (l.i32_count > 0) {
local_decls.push({count: l.i32_count, type: kWasmI32});
}
if (l.i64_count > 0) {
local_decls.push({count: l.i64_count, type: kWasmI64});
}
if (l.f32_count > 0) {
local_decls.push({count: l.f32_count, type: kWasmF32});
}
if (l.f64_count > 0) {
local_decls.push({count: l.f64_count, type: kWasmF64});
}
if (l.s128_count > 0) {
local_decls.push({count: l.s128_count, type: kWasmS128});
}
if (l.anyref_count > 0) {
local_decls.push({count: l.anyref_count, type: kWasmExternRef});
}
if (l.anyfunc_count > 0) {
local_decls.push({count: l.anyfunc_count, type: kWasmAnyFunc});
}
}
header.emit_u32v(local_decls.length);
for (let decl of local_decls) {
header.emit_u32v(decl.count);
header.emit_type(decl.type);
}
section.emit_u32v(header.length + func.body.length);
section.emit_bytes(header.trunc_buffer());
section.emit_bytes(func.body);
}
});
}
// Add data segments.
if (wasm.data_segments.length > 0) {
if (debug) print("emitting data segments @ " + binary.length);
binary.emit_section(kDataSectionCode, section => {
section.emit_u32v(wasm.data_segments.length);
for (let seg of wasm.data_segments) {
if (seg.is_active) {
section.emit_u8(0); // linear memory index 0 / flags
if (seg.is_global) {
// initializer is a global variable
section.emit_u8(kExprGlobalGet);
section.emit_u32v(seg.addr);
} else {
// initializer is a constant
section.emit_u8(kExprI32Const);
section.emit_u32v(seg.addr);
}
section.emit_u8(kExprEnd);
} else {
section.emit_u8(kPassive); // flags
}
section.emit_u32v(seg.data.length);
section.emit_bytes(seg.data);
}
});
}
// Add any explicitly added sections
for (let exp of wasm.explicit) {
if (debug) print("emitting explicit @ " + binary.length);
binary.emit_bytes(exp);
}
// Add names.
let num_function_names = 0;
let num_functions_with_local_names = 0;
for (let func of wasm.functions) {
if (func.name !== undefined) ++num_function_names;
if (func.numLocalNames() > 0) ++num_functions_with_local_names;
}
if (num_function_names > 0 || num_functions_with_local_names > 0 ||
wasm.name !== undefined) {
if (debug) print('emitting names @ ' + binary.length);
binary.emit_section(kUnknownSectionCode, section => {
section.emit_string('name');
// Emit module name.
if (wasm.name !== undefined) {
section.emit_section(kModuleNameCode, name_section => {
name_section.emit_string(wasm.name);
});
}
// Emit function names.
if (num_function_names > 0) {
section.emit_section(kFunctionNamesCode, name_section => {
name_section.emit_u32v(num_function_names);
for (let func of wasm.functions) {
if (func.name === undefined) continue;
name_section.emit_u32v(func.index);
name_section.emit_string(func.name);
}
});
}
// Emit local names.
if (num_functions_with_local_names > 0) {
section.emit_section(kLocalNamesCode, name_section => {
name_section.emit_u32v(num_functions_with_local_names);
for (let func of wasm.functions) {
if (func.numLocalNames() == 0) continue;
name_section.emit_u32v(func.index);
name_section.emit_u32v(func.numLocalNames());
for (let i = 0; i < func.local_names.length; ++i) {
if (func.local_names[i] === undefined) continue;
name_section.emit_u32v(i);
name_section.emit_string(func.local_names[i]);
}
}
});
}
});
}
return binary.trunc_buffer();
}
toArray(debug = false) {
return Array.from(this.toBuffer(debug));
}
instantiate(ffi) {
let module = this.toModule();
let instance = new WebAssembly.Instance(module, ffi);
return instance;
}
asyncInstantiate(ffi) {
return WebAssembly.instantiate(this.toBuffer(), ffi)
.then(({module, instance}) => instance);
}
toModule(debug = false) {
return new WebAssembly.Module(this.toBuffer(debug));
}
}
globalThis.WasmModuleBuilder = WasmModuleBuilder;
function wasmSignedLeb(val, max_len = 5) {
let res = [];
for (let i = 0; i < max_len; ++i) {
let v = val & 0x7f;
// If {v} sign-extended from 7 to 32 bits is equal to val, we are done.
if (((v << 25) >> 25) == val) {
res.push(v);
return res;
}
res.push(v | 0x80);
val = val >> 7;
}
throw new Error(
'Leb value <' + val + '> exceeds maximum length of ' + max_len);
}
globalThis.wasmSignedLeb = wasmSignedLeb;
function wasmI32Const(val) {
return [kExprI32Const, ...wasmSignedLeb(val, 5)];
}
globalThis.wasmI32Const = wasmI32Const;
function wasmF32Const(f) {
// Write in little-endian order at offset 0.
data_view.setFloat32(0, f, true);
return [
kExprF32Const, byte_view[0], byte_view[1], byte_view[2], byte_view[3]
];
}
globalThis.wasmI32Const = wasmI32Const;
function wasmF64Const(f) {
// Write in little-endian order at offset 0.
data_view.setFloat64(0, f, true);
return [
kExprF64Const, byte_view[0], byte_view[1], byte_view[2],
byte_view[3], byte_view[4], byte_view[5], byte_view[6], byte_view[7]
];
}
globalThis.wasmF64Const = wasmF64Const;