46 lines
1.3 KiB
JavaScript
46 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 isTypedArray = require('is-typed-array');
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var typedArrayByteOffset = require('typed-array-byte-offset');
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var typedArrayLength = require('typed-array-length');
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var whichTypedArray = require('which-typed-array');
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var tableTAO = require('./tables/typed-array-objects');
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// https://262.ecma-international.org/12.0/#sec-validateatomicaccess
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module.exports = function ValidateAtomicAccess(typedArray, requestIndex) {
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if (!isTypedArray(typedArray)) {
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throw new $TypeError('Assertion failed: `typedArray` must be a TypedArray'); // step 1
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}
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var length = typedArrayLength(typedArray); // step 2
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var accessIndex = ToIndex(requestIndex); // step 3
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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 $RangeError('index out of range'); // step 5
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}
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var arrayTypeName = whichTypedArray(typedArray); // step 6
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var taType = tableTAO.name['$' + arrayTypeName];
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var elementSize = tableTAO.size['$' + taType]; // step 7
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var offset = typedArrayByteOffset(typedArray); // step 8
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return (accessIndex * elementSize) + offset; // step 9
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};
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