forked from lix-project/lix-website
44 lines
1.3 KiB
JavaScript
44 lines
1.3 KiB
JavaScript
'use strict';
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var $RangeError = require('es-errors/range');
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var $TypeError = require('es-errors/type');
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var ToIndex = require('./ToIndex');
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var TypedArrayElementSize = require('./TypedArrayElementSize');
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var TypedArrayLength = require('./TypedArrayLength');
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var isTypedArrayWithBufferWitnessRecord = require('../helpers/records/typed-array-with-buffer-witness-record');
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var typedArrayByteOffset = require('typed-array-byte-offset');
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// https://262.ecma-international.org/15.0/#sec-validateatomicaccess
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module.exports = function ValidateAtomicAccess(taRecord, requestIndex) {
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if (!isTypedArrayWithBufferWitnessRecord(taRecord)) {
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throw new $TypeError('Assertion failed: `taRecord` must be a TypedArray With Buffer Witness Record');
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}
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var length = TypedArrayLength(taRecord); // step 1
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var accessIndex = ToIndex(requestIndex); // step 2
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/*
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// this assertion can never be reached
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if (!(accessIndex >= 0)) {
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throw new $TypeError('Assertion failed: accessIndex >= 0'); // step 4
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}
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*/
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if (accessIndex >= length) {
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throw new $RangeError('index out of range'); // step 4
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}
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var typedArray = taRecord['[[Object]]']; // step 5
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var elementSize = TypedArrayElementSize(typedArray); // step 6
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var offset = typedArrayByteOffset(typedArray); // step 7
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return (accessIndex * elementSize) + offset; // step 8
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};
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