1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
|
// |reftest| skip-if(!this.hasOwnProperty('Atomics')||!this.hasOwnProperty('SharedArrayBuffer')||(this.hasOwnProperty('getBuildConfiguration')&&getBuildConfiguration()['arm64-simulator'])) -- Atomics,SharedArrayBuffer is not enabled unconditionally, ARM64 Simulator cannot emulate atomics
// Copyright (C) 2018 Rick Waldron. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-atomics.exchange
description: >
Atomics.and returns the value that existed at the
index prior to the operation.
info: |
Atomics.exchange( typedArray, index, value )
1. Return ? AtomicReadModifyWrite(typedArray, index, value, second).
AtomicReadModifyWrite( typedArray, index, value, op )
...
9. Return GetModifySetValueInBuffer(buffer, indexedPosition,
elementType, v, op).
GetModifySetValueInBuffer( arrayBuffer,
byteIndex, type, value, op [ , isLittleEndian ] )
...
16. Return RawBytesToNumber(type, rawBytesRead, isLittleEndian).
features: [Atomics, SharedArrayBuffer, TypedArray]
---*/
const i32a = new Int32Array(
new SharedArrayBuffer(Int32Array.BYTES_PER_ELEMENT * 4)
);
const update = 0b00000001000000001000000010000001;
assert.sameValue(
Atomics.exchange(i32a, 0, update),
0,
'Atomics.exchange(i32a, 0, update) returns 0'
);
assert.sameValue(
i32a[0],
update,
'The value of i32a[0] equals the value of `update` (0b00000001000000001000000010000001)'
);
reportCompare(0, 0);
|
