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// |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 Amal Hussein. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-atomics.wait
description: >
New waiters should be applied to the end of the list and woken by order they entered the list (FIFO)
info: |
Atomics.wait( typedArray, index, value, timeout )
16.Perform AddWaiter(WL, W).
...
3.Add W to the end of the list of waiters in WL.
includes: [atomicsHelper.js]
features: [Atomics, BigInt, SharedArrayBuffer, TypedArray]
---*/
var WAIT_INDEX = 0;
var RUNNING = 1;
var LOCK_INDEX = 2;
var NUMAGENT = 3;
const i64a = new BigInt64Array(
new SharedArrayBuffer(BigInt64Array.BYTES_PER_ELEMENT * 4)
);
for (var i = 0; i < NUMAGENT; i++) {
var agentNum = i;
$262.agent.start(`
$262.agent.receiveBroadcast(function(sab) {
const i64a = new BigInt64Array(sab);
Atomics.add(i64a, ${RUNNING}, 1n);
// Synchronize workers before reporting the initial report.
while (Atomics.compareExchange(i64a, ${LOCK_INDEX}, 0n, 1n) !== 0n) ;
// Report the agent number before waiting.
$262.agent.report(${agentNum});
// Wait until restarted by main thread.
var status = Atomics.wait(i64a, ${WAIT_INDEX}, 0n);
// Report wait status.
$262.agent.report(status);
// Report the agent number after waiting.
$262.agent.report(${agentNum});
$262.agent.leaving();
});
`);
}
$262.agent.safeBroadcast(i64a);
// Wait until all agents started.
$262.agent.waitUntil(i64a, RUNNING, BigInt(NUMAGENT));
// Agents may be started in any order.
const started = [];
for (var i = 0; i < NUMAGENT; i++) {
// Wait until an agent entered its critical section.
$262.agent.waitUntil(i64a, LOCK_INDEX, 1n);
// Record the agent number.
started.push($262.agent.getReport());
// The agent may have been interrupted between reporting its initial report
// and the `Atomics.wait` call. Try to yield control to ensure the agent
// actually started to wait.
$262.agent.tryYield();
// Now continue with the next agent.
Atomics.store(i64a, LOCK_INDEX, 0n);
}
// Agents must notify in the order they waited.
for (var i = 0; i < NUMAGENT; i++) {
var woken = 0;
while ((woken = Atomics.notify(i64a, WAIT_INDEX, 1)) === 0) ;
assert.sameValue(woken, 1,
'Atomics.notify(i64a, WAIT_INDEX, 1) returns 1, at index = ' + i);
assert.sameValue($262.agent.getReport(), 'ok',
'$262.agent.getReport() returns "ok", at index = ' + i);
assert.sameValue($262.agent.getReport(), started[i],
'$262.agent.getReport() returns the value of `started[' + i + ']`');
}
reportCompare(0, 0);