test262/test/built-ins/Atomics/compareExchange/good-views.js

75 lines
2.7 KiB
JavaScript

// Copyright (C) 2017 Mozilla Corporation. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-atomics.compareexchange
description: Test Atomics.compareExchange on arrays that allow atomic operations.
includes: [testAtomics.js, testTypedArray.js]
features: [SharedArrayBuffer, ArrayBuffer, DataView, Atomics, arrow-function, let, TypedArray, for-of]
---*/
var sab = new SharedArrayBuffer(1024);
var ab = new ArrayBuffer(16);
var int_views = [Int8Array, Uint8Array, Int16Array, Uint16Array, Int32Array, Uint32Array];
var good_indices = [ (view) => 0/-1, // -0
(view) => '-0',
(view) => view.length - 1,
(view) => ({ valueOf: () => 0 }),
(view) => ({ toString: () => '0', valueOf: false }) // non-callable valueOf triggers invocation of toString
];
testWithTypedArrayConstructors(function(View) {
// Make it interesting - use non-zero byteOffsets and non-zero indexes.
var view = new View(sab, 32, 20);
var control = new View(ab, 0, 2);
// Performs the exchange
view[8] = 0;
assert.sameValue(Atomics.compareExchange(view, 8, 0, 10), 0);
assert.sameValue(view[8], 10);
view[8] = 0;
assert.sameValue(Atomics.compareExchange(view, 8, 1, 10), 0,
"Does not perform the exchange");
assert.sameValue(view[8], 0);
view[8] = 0;
assert.sameValue(Atomics.compareExchange(view, 8, 0, -5), 0,
"Performs the exchange, coercing the value being stored");
control[0] = -5;
assert.sameValue(view[8], control[0]);
view[3] = -5;
control[0] = -5;
assert.sameValue(Atomics.compareExchange(view, 3, -5, 0), control[0],
"Performs the exchange, coercing the value being tested");
assert.sameValue(view[3], 0);
control[0] = 12345;
view[3] = 12345;
assert.sameValue(Atomics.compareExchange(view, 3, 12345, 0), control[0],
"Performs the exchange, chopping the value being tested");
assert.sameValue(view[3], 0);
control[0] = 123456789;
view[3] = 123456789;
assert.sameValue(Atomics.compareExchange(view, 3, 123456789, 0), control[0],
"Performs the exchange, chopping the value being tested");
assert.sameValue(view[3], 0);
// In-bounds boundary cases for indexing
testWithAtomicsInBoundsIndices(function(IdxGen) {
let Idx = IdxGen(view);
view.fill(0);
// Atomics.store() computes an index from Idx in the same way as other
// Atomics operations, not quite like view[Idx].
Atomics.store(view, Idx, 37);
assert.sameValue(Atomics.compareExchange(view, Idx, 37, 0), 37);
});
}, int_views);