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|
// Copyright 2018 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.
module data_view {
extern operator '.buffer'
macro LoadArrayBufferViewBuffer(JSArrayBufferView): JSArrayBuffer;
extern operator '.byte_length'
macro LoadDataViewByteLength(JSDataView): Number;
extern operator '.byte_offset'
macro LoadDataViewByteOffset(JSDataView): Number;
extern operator '.backing_store'
macro LoadArrayBufferBackingStore(JSArrayBuffer): RawPtr;
macro WasNeutered(view: JSArrayBufferView): bool {
return IsDetachedBuffer(view.buffer);
}
macro ValidateDataView(context: Context,
o: Object, method: String): JSDataView {
try {
return cast<JSDataView>(o) otherwise CastError;
}
label CastError {
ThrowTypeError(context, kIncompatibleMethodReceiver, method);
}
}
// ES6 section 24.2.4.1 get DataView.prototype.buffer
javascript builtin DataViewPrototypeGetBuffer(
context: Context, receiver: Object, ...arguments): JSArrayBuffer {
let data_view: JSDataView = ValidateDataView(
context, receiver, 'get DataView.prototype.buffer');
return data_view.buffer;
}
// ES6 section 24.2.4.2 get DataView.prototype.byteLength
javascript builtin DataViewPrototypeGetByteLength(
context: Context, receiver: Object, ...arguments): Number {
let data_view: JSDataView = ValidateDataView(
context, receiver, 'get DataView.prototype.byte_length');
if (WasNeutered(data_view)) {
// TODO(bmeurer): According to the ES6 spec, we should throw a TypeError
// here if the JSArrayBuffer of the {data_view} was neutered.
return 0;
}
return data_view.byte_length;
}
// ES6 section 24.2.4.3 get DataView.prototype.byteOffset
javascript builtin DataViewPrototypeGetByteOffset(
context: Context, receiver: Object, ...arguments): Number {
let data_view: JSDataView = ValidateDataView(
context, receiver, 'get DataView.prototype.byte_offset');
if (WasNeutered(data_view)) {
// TODO(bmeurer): According to the ES6 spec, we should throw a TypeError
// here if the JSArrayBuffer of the {data_view} was neutered.
return 0;
}
return data_view.byte_offset;
}
extern macro BitcastInt32ToFloat32(uint32): float32;
extern macro BitcastFloat32ToInt32(float32): uint32;
extern macro Float64ExtractLowWord32(float64): uint32;
extern macro Float64ExtractHighWord32(float64): uint32;
extern macro Float64InsertLowWord32(float64, uint32): float64;
extern macro Float64InsertHighWord32(float64, uint32): float64;
extern macro LoadUint8(RawPtr, intptr): uint32;
extern macro LoadInt8(RawPtr, intptr): int32;
macro LoadDataViewUint8(buffer: JSArrayBuffer, offset: intptr): Smi {
return convert<Smi>(LoadUint8(buffer.backing_store, offset));
}
macro LoadDataViewInt8(buffer: JSArrayBuffer, offset: intptr): Smi {
return convert<Smi>(LoadInt8(buffer.backing_store, offset));
}
macro LoadDataView16(buffer: JSArrayBuffer, offset: intptr,
requested_little_endian: bool,
signed: constexpr bool): Number {
let data_pointer: RawPtr = buffer.backing_store;
let b0: int32;
let b1: int32;
let result: int32;
// Sign-extend the most significant byte by loading it as an Int8.
if (requested_little_endian) {
b0 = Signed(LoadUint8(data_pointer, offset));
b1 = LoadInt8(data_pointer, offset + 1);
result = (b1 << 8) + b0;
} else {
b0 = LoadInt8(data_pointer, offset);
b1 = Signed(LoadUint8(data_pointer, offset + 1));
result = (b0 << 8) + b1;
}
if constexpr (signed) {
return convert<Smi>(result);
} else {
// Bit-mask the higher bits to prevent sign extension if we're unsigned.
return convert<Smi>(result & 0xFFFF);
}
}
macro LoadDataView32(buffer: JSArrayBuffer, offset: intptr,
requested_little_endian: bool,
signed: constexpr bool): Number {
let data_pointer: RawPtr = buffer.backing_store;
let b0: uint32 = LoadUint8(data_pointer, offset);
let b1: uint32 = LoadUint8(data_pointer, offset + 1);
let b2: uint32 = LoadUint8(data_pointer, offset + 2);
let b3: uint32 = LoadUint8(data_pointer, offset + 3);
let result: uint32;
if (requested_little_endian) {
result = (b3 << 24) | (b2 << 16) | (b1 << 8) | b0;
} else {
result = (b0 << 24) | (b1 << 16) | (b2 << 8) | b3;
}
if constexpr (signed) {
return convert<Number>(Signed(result));
} else {
return convert<Number>(result);
}
}
macro LoadDataViewFloat32(buffer: JSArrayBuffer, offset: intptr,
requested_little_endian: bool): Number {
let data_pointer: RawPtr = buffer.backing_store;
let b0: uint32 = LoadUint8(data_pointer, offset);
let b1: uint32 = LoadUint8(data_pointer, offset + 1);
let b2: uint32 = LoadUint8(data_pointer, offset + 2);
let b3: uint32 = LoadUint8(data_pointer, offset + 3);
let result: uint32;
if (requested_little_endian) {
result = (b3 << 24) | (b2 << 16) | (b1 << 8) | b0;
} else {
result = (b0 << 24) | (b1 << 16) | (b2 << 8) | b3;
}
let float_res: float64 = convert<float64>(BitcastInt32ToFloat32(result));
return convert<Number>(float_res);
}
macro LoadDataViewFloat64(buffer: JSArrayBuffer, offset: intptr,
requested_little_endian: bool): Number {
let data_pointer: RawPtr = buffer.backing_store;
let b0: uint32 = LoadUint8(data_pointer, offset);
let b1: uint32 = LoadUint8(data_pointer, offset + 1);
let b2: uint32 = LoadUint8(data_pointer, offset + 2);
let b3: uint32 = LoadUint8(data_pointer, offset + 3);
let b4: uint32 = LoadUint8(data_pointer, offset + 4);
let b5: uint32 = LoadUint8(data_pointer, offset + 5);
let b6: uint32 = LoadUint8(data_pointer, offset + 6);
let b7: uint32 = LoadUint8(data_pointer, offset + 7);
let low_word: uint32;
let high_word: uint32;
if (requested_little_endian) {
low_word = (b3 << 24) | (b2 << 16) | (b1 << 8) | b0;
high_word = (b7 << 24) | (b6 << 16) | (b5 << 8) | b4;
} else {
high_word = (b0 << 24) | (b1 << 16) | (b2 << 8) | b3;
low_word = (b4 << 24) | (b5 << 16) | (b6 << 8) | b7;
}
let result: float64 = 0;
result = Float64InsertLowWord32(result, low_word);
result = Float64InsertHighWord32(result, high_word);
return convert<Number>(result);
}
extern macro AllocateBigInt(intptr): BigInt;
extern macro StoreBigIntBitfield(BigInt, intptr): void;
extern macro StoreBigIntDigit(BigInt, constexpr int31, uintptr): void;
extern macro DataViewEncodeBigIntBits(constexpr bool,
constexpr int31): intptr;
const kPositiveBigInt: constexpr bool generates 'false';
const kNegativeBigInt: constexpr bool generates 'true';
const kZeroDigitBigInt: constexpr int31 generates '0';
const kOneDigitBigInt: constexpr int31 generates '1';
const kTwoDigitBigInt: constexpr int31 generates '2';
macro CreateEmptyBigInt(is_positive: bool, length: constexpr int31): BigInt {
// Allocate a BigInt with the desired length (number of digits).
let result: BigInt = AllocateBigInt(length);
// Write the desired sign and length to the BigInt bitfield.
if (is_positive) {
StoreBigIntBitfield(result,
DataViewEncodeBigIntBits(kPositiveBigInt, length));
} else {
StoreBigIntBitfield(result,
DataViewEncodeBigIntBits(kNegativeBigInt, length));
}
return result;
}
// Create a BigInt on a 64-bit architecture from two 32-bit values.
macro MakeBigIntOn64Bit(low_word: uint32, high_word: uint32,
signed: constexpr bool): BigInt {
// 0n is represented by a zero-length BigInt.
if (low_word == 0 && high_word == 0) {
return AllocateBigInt(kZeroDigitBigInt);
}
let is_positive: bool = true;
let high_part: intptr = Signed(convert<uintptr>(high_word));
let low_part: intptr = Signed(convert<uintptr>(low_word));
let raw_value: intptr = (high_part << 32) + low_part;
if constexpr (signed) {
if (raw_value < 0) {
is_positive = false;
// We have to store the absolute value of raw_value in the digit.
raw_value = 0 - raw_value;
}
}
// Allocate the BigInt and store the absolute value.
let result: BigInt = CreateEmptyBigInt(is_positive, kOneDigitBigInt);
StoreBigIntDigit(result, 0, Unsigned(raw_value));
return result;
}
// Create a BigInt on a 32-bit architecture from two 32-bit values.
macro MakeBigIntOn32Bit(low_word: uint32, high_word: uint32,
signed: constexpr bool): BigInt {
// 0n is represented by a zero-length BigInt.
if (low_word == 0 && high_word == 0) {
return AllocateBigInt(kZeroDigitBigInt);
}
// On a 32-bit platform, we might need 1 or 2 digits to store the number.
let need_two_digits: bool = false;
let is_positive: bool = true;
// We need to do some math on low_word and high_word,
// so convert them to int32.
let low_part: int32 = Signed(low_word);
let high_part: int32 = Signed(high_word);
// If high_word == 0, the number is positive, and we only need 1 digit,
// so we don't have anything to do.
// Otherwise, all cases are possible.
if (high_word != 0) {
if constexpr (signed) {
// If high_part < 0, the number is always negative.
if (high_part < 0) {
is_positive = false;
// We have to compute the absolute value by hand.
// There will be a negative carry from the low word
// to the high word iff low != 0.
high_part = 0 - high_part;
if (low_part != 0) {
high_part = high_part - 1;
}
low_part = 0 - low_part;
// Here, high_part could be 0 again so we might have 1 or 2 digits.
if (high_part != 0) {
need_two_digits = true;
}
} else {
// In this case, the number is positive, and we need 2 digits.
need_two_digits = true;
}
} else {
// In this case, the number is positive (unsigned),
// and we need 2 digits.
need_two_digits = true;
}
}
// Allocate the BigInt with the right sign and length.
let result: BigInt;
if (need_two_digits) {
result = CreateEmptyBigInt(is_positive, kTwoDigitBigInt);
} else {
result = CreateEmptyBigInt(is_positive, kOneDigitBigInt);
}
// Finally, write the digit(s) to the BigInt.
StoreBigIntDigit(result, 0, Unsigned(convert<intptr>(low_part)));
if (need_two_digits) {
StoreBigIntDigit(result, 1, Unsigned(convert<intptr>(high_part)));
}
return result;
}
macro MakeBigInt(low_word: uint32, high_word: uint32,
signed: constexpr bool): BigInt {
// A BigInt digit has the platform word size, so we only need one digit
// on 64-bit platforms but may need two on 32-bit.
if constexpr (Is64()) {
return MakeBigIntOn64Bit(low_word, high_word, signed);
} else {
return MakeBigIntOn32Bit(low_word, high_word, signed);
}
}
macro LoadDataViewBigInt(buffer: JSArrayBuffer, offset: intptr,
requested_little_endian: bool,
signed: constexpr bool): BigInt {
let data_pointer: RawPtr = buffer.backing_store;
let b0: uint32 = LoadUint8(data_pointer, offset);
let b1: uint32 = LoadUint8(data_pointer, offset + 1);
let b2: uint32 = LoadUint8(data_pointer, offset + 2);
let b3: uint32 = LoadUint8(data_pointer, offset + 3);
let b4: uint32 = LoadUint8(data_pointer, offset + 4);
let b5: uint32 = LoadUint8(data_pointer, offset + 5);
let b6: uint32 = LoadUint8(data_pointer, offset + 6);
let b7: uint32 = LoadUint8(data_pointer, offset + 7);
let low_word: uint32;
let high_word: uint32;
if (requested_little_endian) {
low_word = (b3 << 24) | (b2 << 16) | (b1 << 8) | b0;
high_word = (b7 << 24) | (b6 << 16) | (b5 << 8) | b4;
} else {
high_word = (b0 << 24) | (b1 << 16) | (b2 << 8) | b3;
low_word = (b4 << 24) | (b5 << 16) | (b6 << 8) | b7;
}
return MakeBigInt(low_word, high_word, signed);
}
extern macro ToSmiIndex(Object, Context): Smi labels RangeError;
extern macro DataViewElementSize(constexpr ElementsKind): constexpr int31;
macro DataViewGet(context: Context,
receiver: Object,
offset: Object,
requested_little_endian: Object,
kind: constexpr ElementsKind): Numeric {
// TODO(theotime): add more specific method name to match
// the former implementation.
let data_view: JSDataView = ValidateDataView(
context, receiver, 'get DataView.prototype.get');
let getIndex: Number;
try {
getIndex = ToIndex(offset, context) otherwise RangeError;
}
label RangeError {
ThrowRangeError(context, kInvalidDataViewAccessorOffset);
}
let littleEndian: bool = ToBoolean(requested_little_endian);
let buffer: JSArrayBuffer = data_view.buffer;
if (IsDetachedBuffer(buffer)) {
ThrowTypeError(context, kDetachedOperation, 'DataView.prototype.get');
}
let viewOffset: Number = data_view.byte_offset;
let viewSize: Number = data_view.byte_length;
let elementSize: Number = DataViewElementSize(kind);
if (getIndex + elementSize > viewSize) {
ThrowRangeError(context, kInvalidDataViewAccessorOffset);
}
let getIndexFloat: float64 = convert<float64>(getIndex);
let getIndexIntptr: intptr = Signed(convert<uintptr>(getIndexFloat));
let viewOffsetFloat: float64 = convert<float64>(viewOffset);
let viewOffsetIntptr: intptr = Signed(convert<uintptr>(viewOffsetFloat));
let bufferIndex: intptr = getIndexIntptr + viewOffsetIntptr;
if constexpr (kind == UINT8_ELEMENTS) {
return LoadDataViewUint8(buffer, bufferIndex);
} else if constexpr (kind == INT8_ELEMENTS) {
return LoadDataViewInt8(buffer, bufferIndex);
} else if constexpr (kind == UINT16_ELEMENTS) {
return LoadDataView16(buffer, bufferIndex, littleEndian, false);
} else if constexpr (kind == INT16_ELEMENTS) {
return LoadDataView16(buffer, bufferIndex, littleEndian, true);
} else if constexpr (kind == UINT32_ELEMENTS) {
return LoadDataView32(buffer, bufferIndex, littleEndian, false);
} else if constexpr (kind == INT32_ELEMENTS) {
return LoadDataView32(buffer, bufferIndex, littleEndian, true);
} else if constexpr (kind == FLOAT32_ELEMENTS) {
return LoadDataViewFloat32(buffer, bufferIndex, littleEndian);
} else if constexpr (kind == FLOAT64_ELEMENTS) {
return LoadDataViewFloat64(buffer, bufferIndex, littleEndian);
} else if constexpr (kind == BIGINT64_ELEMENTS) {
return LoadDataViewBigInt(buffer, bufferIndex, littleEndian, true);
} else if constexpr (kind == BIGUINT64_ELEMENTS) {
return LoadDataViewBigInt(buffer, bufferIndex, littleEndian, false);
} else {
unreachable;
}
}
javascript builtin DataViewPrototypeGetInt8(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
return DataViewGet(context, receiver, offset, Undefined, INT8_ELEMENTS);
}
javascript builtin DataViewPrototypeGetUint8(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
return DataViewGet(context, receiver, offset, Undefined, UINT8_ELEMENTS);
}
javascript builtin DataViewPrototypeGetInt16(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let is_little_endian : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
return DataViewGet(context, receiver, offset, is_little_endian,
INT16_ELEMENTS);
}
javascript builtin DataViewPrototypeGetUint16(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let is_little_endian : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
return DataViewGet(context, receiver, offset, is_little_endian,
UINT16_ELEMENTS);
}
javascript builtin DataViewPrototypeGetInt32(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let is_little_endian : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
return DataViewGet(context, receiver, offset, is_little_endian,
INT32_ELEMENTS);
}
javascript builtin DataViewPrototypeGetUint32(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let is_little_endian : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
return DataViewGet(context, receiver, offset, is_little_endian,
UINT32_ELEMENTS);
}
javascript builtin DataViewPrototypeGetFloat32(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let is_little_endian : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
return DataViewGet(context, receiver, offset, is_little_endian,
FLOAT32_ELEMENTS);
}
javascript builtin DataViewPrototypeGetFloat64(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let is_little_endian : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
return DataViewGet(context, receiver, offset, is_little_endian,
FLOAT64_ELEMENTS);
}
javascript builtin DataViewPrototypeGetBigInt64(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let is_little_endian : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
return DataViewGet(context, receiver, offset, is_little_endian,
BIGINT64_ELEMENTS);
}
javascript builtin DataViewPrototypeGetBigUint64(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let is_little_endian : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
return DataViewGet(context, receiver, offset, is_little_endian,
BIGUINT64_ELEMENTS);
}
extern macro ToNumber(Context, Object): Number;
extern macro ToBigInt(Context, Object): BigInt;
extern macro TruncateFloat64ToFloat32(float64): float32;
extern macro TruncateFloat64ToWord32(float64): uint32;
extern macro StoreWord8(RawPtr, intptr, uint32): void;
macro StoreDataView8(buffer: JSArrayBuffer, offset: intptr,
value: uint32) {
StoreWord8(buffer.backing_store, offset, value & 0xFF);
}
macro StoreDataView16(buffer: JSArrayBuffer, offset: intptr, value: uint32,
requested_little_endian: bool) {
let data_pointer: RawPtr = buffer.backing_store;
let b0: uint32 = value & 0xFF;
let b1: uint32 = (value >>> 8) & 0xFF;
if (requested_little_endian) {
StoreWord8(data_pointer, offset, b0);
StoreWord8(data_pointer, offset + 1, b1);
} else {
StoreWord8(data_pointer, offset, b1);
StoreWord8(data_pointer, offset + 1, b0);
}
}
macro StoreDataView32(buffer: JSArrayBuffer, offset: intptr, value: uint32,
requested_little_endian: bool) {
let data_pointer: RawPtr = buffer.backing_store;
let b0: uint32 = value & 0xFF;
let b1: uint32 = (value >>> 8) & 0xFF;
let b2: uint32 = (value >>> 16) & 0xFF;
let b3: uint32 = value >>> 24; // We don't need to mask here.
if (requested_little_endian) {
StoreWord8(data_pointer, offset, b0);
StoreWord8(data_pointer, offset + 1, b1);
StoreWord8(data_pointer, offset + 2, b2);
StoreWord8(data_pointer, offset + 3, b3);
} else {
StoreWord8(data_pointer, offset, b3);
StoreWord8(data_pointer, offset + 1, b2);
StoreWord8(data_pointer, offset + 2, b1);
StoreWord8(data_pointer, offset + 3, b0);
}
}
macro StoreDataView64(buffer: JSArrayBuffer, offset: intptr,
low_word: uint32, high_word: uint32,
requested_little_endian: bool) {
let data_pointer: RawPtr = buffer.backing_store;
let b0: uint32 = low_word & 0xFF;
let b1: uint32 = (low_word >>> 8) & 0xFF;
let b2: uint32 = (low_word >>> 16) & 0xFF;
let b3: uint32 = low_word >>> 24;
let b4: uint32 = high_word & 0xFF;
let b5: uint32 = (high_word >>> 8) & 0xFF;
let b6: uint32 = (high_word >>> 16) & 0xFF;
let b7: uint32 = high_word >>> 24;
if (requested_little_endian) {
StoreWord8(data_pointer, offset, b0);
StoreWord8(data_pointer, offset + 1, b1);
StoreWord8(data_pointer, offset + 2, b2);
StoreWord8(data_pointer, offset + 3, b3);
StoreWord8(data_pointer, offset + 4, b4);
StoreWord8(data_pointer, offset + 5, b5);
StoreWord8(data_pointer, offset + 6, b6);
StoreWord8(data_pointer, offset + 7, b7);
} else {
StoreWord8(data_pointer, offset, b7);
StoreWord8(data_pointer, offset + 1, b6);
StoreWord8(data_pointer, offset + 2, b5);
StoreWord8(data_pointer, offset + 3, b4);
StoreWord8(data_pointer, offset + 4, b3);
StoreWord8(data_pointer, offset + 5, b2);
StoreWord8(data_pointer, offset + 6, b1);
StoreWord8(data_pointer, offset + 7, b0);
}
}
extern macro DataViewDecodeBigIntLength(BigInt): uintptr;
extern macro DataViewDecodeBigIntSign(BigInt): uintptr;
extern macro LoadBigIntDigit(BigInt, constexpr int31): uintptr;
// We might get here a BigInt that is bigger than 64 bits, but we're only
// interested in the 64 lowest ones. This means the lowest BigInt digit
// on 64-bit platforms, and the 2 lowest BigInt digits on 32-bit ones.
macro StoreDataViewBigInt(buffer: JSArrayBuffer, offset: intptr,
bigint_value: BigInt,
requested_little_endian: bool) {
let length: uintptr = DataViewDecodeBigIntLength(bigint_value);
let sign: uintptr = DataViewDecodeBigIntSign(bigint_value);
// The 32-bit words that will hold the BigInt's value in
// two's complement representation.
let low_word: uint32 = 0;
let high_word: uint32 = 0;
// The length is nonzero if and only if the BigInt's value is nonzero.
if (length != 0) {
if constexpr (Is64()) {
// There is always exactly 1 BigInt digit to load in this case.
let value: uintptr = LoadBigIntDigit(bigint_value, 0);
low_word = convert<uint32>(value); // Truncates value to 32 bits.
high_word = convert<uint32>(value >>> 32);
}
else { // There might be either 1 or 2 BigInt digits we need to load.
low_word = convert<uint32>(LoadBigIntDigit(bigint_value, 0));
if (length >= 2) { // Only load the second digit if there is one.
high_word = convert<uint32>(LoadBigIntDigit(bigint_value, 1));
}
}
}
if (sign != 0) { // The number is negative, convert it.
high_word = Unsigned(0 - Signed(high_word));
if (low_word != 0) {
high_word = Unsigned(Signed(high_word) - 1);
}
low_word = Unsigned(0 - Signed(low_word));
}
StoreDataView64(buffer, offset, low_word, high_word,
requested_little_endian);
}
macro DataViewSet(context: Context,
receiver: Object,
offset: Object,
value: Object,
requested_little_endian: Object,
kind: constexpr ElementsKind): Object {
// TODO(theotime): add more specific method name to match
// the former implementation.
let data_view: JSDataView = ValidateDataView(
context, receiver, 'get DataView.prototype.get');
let getIndex: Number;
try {
getIndex = ToIndex(offset, context) otherwise RangeError;
}
label RangeError {
ThrowRangeError(context, kInvalidDataViewAccessorOffset);
}
let littleEndian: bool = ToBoolean(requested_little_endian);
let buffer: JSArrayBuffer = data_view.buffer;
let bigint_value: BigInt;
let num_value: Number;
// According to ES6 section 24.2.1.2 SetViewValue, we must perform
// the conversion before doing the bounds check.
if constexpr (kind == BIGUINT64_ELEMENTS || kind == BIGINT64_ELEMENTS) {
bigint_value = ToBigInt(context, value);
} else {
num_value = ToNumber(context, value);
}
if (IsDetachedBuffer(buffer)) {
ThrowTypeError(context, kDetachedOperation, 'DataView.prototype.get');
}
let viewOffset: Number = data_view.byte_offset;
let viewSize: Number = data_view.byte_length;
let elementSize: Number = DataViewElementSize(kind);
if (getIndex + elementSize > viewSize) {
ThrowRangeError(context, kInvalidDataViewAccessorOffset);
}
let getIndexFloat: float64 = convert<float64>(getIndex);
let getIndexIntptr: intptr = Signed(convert<uintptr>(getIndexFloat));
let viewOffsetFloat: float64 = convert<float64>(viewOffset);
let viewOffsetIntptr: intptr = Signed(convert<uintptr>(viewOffsetFloat));
let bufferIndex: intptr = getIndexIntptr + viewOffsetIntptr;
if constexpr (kind == BIGUINT64_ELEMENTS || kind == BIGINT64_ELEMENTS) {
StoreDataViewBigInt(buffer, bufferIndex, bigint_value,
littleEndian);
}
else {
let double_value: float64 = ChangeNumberToFloat64(num_value);
if constexpr (kind == UINT8_ELEMENTS || kind == INT8_ELEMENTS) {
StoreDataView8(buffer, bufferIndex,
TruncateFloat64ToWord32(double_value));
}
else if constexpr (kind == UINT16_ELEMENTS || kind == INT16_ELEMENTS) {
StoreDataView16(buffer, bufferIndex,
TruncateFloat64ToWord32(double_value), littleEndian);
}
else if constexpr (kind == UINT32_ELEMENTS || kind == INT32_ELEMENTS) {
StoreDataView32(buffer, bufferIndex,
TruncateFloat64ToWord32(double_value), littleEndian);
}
else if constexpr (kind == FLOAT32_ELEMENTS) {
let float_value: float32 = TruncateFloat64ToFloat32(double_value);
StoreDataView32(buffer, bufferIndex,
BitcastFloat32ToInt32(float_value), littleEndian);
}
else if constexpr (kind == FLOAT64_ELEMENTS) {
let low_word: uint32 = Float64ExtractLowWord32(double_value);
let high_word: uint32 = Float64ExtractHighWord32(double_value);
StoreDataView64(buffer, bufferIndex, low_word, high_word,
littleEndian);
}
}
return Undefined;
}
javascript builtin DataViewPrototypeSetInt8(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let value : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
return DataViewSet(context, receiver, offset, value, Undefined,
INT8_ELEMENTS);
}
javascript builtin DataViewPrototypeSetUint8(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let value : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
return DataViewSet(context, receiver, offset, value, Undefined,
UINT8_ELEMENTS);
}
javascript builtin DataViewPrototypeSetInt16(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let value : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
let is_little_endian : Object = arguments.length > 2 ?
arguments[2] :
Undefined;
return DataViewSet(context, receiver, offset, value,
is_little_endian, INT16_ELEMENTS);
}
javascript builtin DataViewPrototypeSetUint16(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let value : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
let is_little_endian : Object = arguments.length > 2 ?
arguments[2] :
Undefined;
return DataViewSet(context, receiver, offset, value,
is_little_endian, UINT16_ELEMENTS);
}
javascript builtin DataViewPrototypeSetInt32(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let value : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
let is_little_endian : Object = arguments.length > 2 ?
arguments[2] :
Undefined;
return DataViewSet(context, receiver, offset, value,
is_little_endian, INT32_ELEMENTS);
}
javascript builtin DataViewPrototypeSetUint32(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let value : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
let is_little_endian : Object = arguments.length > 2 ?
arguments[2] :
Undefined;
return DataViewSet(context, receiver, offset, value,
is_little_endian, UINT32_ELEMENTS);
}
javascript builtin DataViewPrototypeSetFloat32(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let value : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
let is_little_endian : Object = arguments.length > 2 ?
arguments[2] :
Undefined;
return DataViewSet(context, receiver, offset, value,
is_little_endian, FLOAT32_ELEMENTS);
}
javascript builtin DataViewPrototypeSetFloat64(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let value : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
let is_little_endian : Object = arguments.length > 2 ?
arguments[2] :
Undefined;
return DataViewSet(context, receiver, offset, value,
is_little_endian, FLOAT64_ELEMENTS);
}
javascript builtin DataViewPrototypeSetBigInt64(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let value : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
let is_little_endian : Object = arguments.length > 2 ?
arguments[2] :
Undefined;
return DataViewSet(context, receiver, offset, value,
is_little_endian, BIGINT64_ELEMENTS);
}
javascript builtin DataViewPrototypeSetBigUint64(
context: Context, receiver: Object, ...arguments): Object {
let offset: Object = arguments.length > 0 ?
arguments[0] :
Undefined;
let value : Object = arguments.length > 1 ?
arguments[1] :
Undefined;
let is_little_endian : Object = arguments.length > 2 ?
arguments[2] :
Undefined;
return DataViewSet(context, receiver, offset, value,
is_little_endian, BIGUINT64_ELEMENTS);
}
}
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