JSTests/stress/lars-sab-workers.js

//@ skip

var sab = new SharedArrayBuffer(100 * 4);

var memory = new Int32Array(sab);

var numWorkers = 0;
function startWorker(code)
{
    print("Starting worker!");
    
    numWorkers++;
    $.agent.start(code);
}

resources = `
function wait(memory, index, waitCondition, wakeCondition)
{
    while (memory[index] == waitCondition) {
        var result = Atomics.wait(memory, index, waitCondition);
        switch (result) {
        case "not-equal":
        case "ok":
            break;
        default:
            $.agent.report("Error: bad result from wait: " + result);
            $.agent.report("error");
            break;
        }
        var value = memory[index];
        if (value != wakeCondition) {
            $.agent.report("Error: wait returned not-equal but the memory has a bad value: " + value);
            $.agent.report("error");
        }
    }
    var value = memory[index];
    if (value != wakeCondition) {
        $.agent.report("Error: done waiting but the memory has a bad value: " + value);
        $.agent.report("error");
    }
}

function wake(memory, index)
{
    var result = Atomics.wake(memory, index, 1);
    if (result != 0 && result != 1) {
        $.agent.report("Error: bad result from wake: " + result);
        $.agent.report("error");
    }
}
`;

startWorker(
    resources + `
    $.agent.receiveBroadcast(sab => {
        var memory = new Int32Array(sab);
        var didStartIdx = 0;
        var shouldGoIdx = 1;
        var didEndIdx = 2;
        
        $.agent.report("1: Started!");
        $.agent.report("1: Memory: " + memory);
        
        wait(memory, didStartIdx, 0, 1);
        
        $.agent.report("1: It started!");
        
        memory[shouldGoIdx] = 1;
        wake(memory, shouldGoIdx);
        
        wait(memory, didEndIdx, 0, 1);
        
        $.agent.report("1: All done!");
        $.agent.report("1: Memory: " + memory);
        $.agent.report("done");
    });
    `);

startWorker(
    resources + `
    $.agent.receiveBroadcast(sab => {
        var memory = new Int32Array(sab);
        var didStartIdx = 0;
        var shouldGoIdx = 1;
        var didEndIdx = 2;
        
        $.agent.report("2: Started!");
        $.agent.report("2: Memory: " + memory);
        
        Atomics.store(memory, didStartIdx, 1);
        wake(memory, didStartIdx);
        
        wait(memory, shouldGoIdx, 0, 1);
        
        Atomics.store(memory, didEndIdx, 1);
        wake(memory, didEndIdx, 1);
        
        $.agent.report("2: Memory: " + memory);
        $.agent.report("done");
    });
    `);

$.agent.broadcast(sab);

for (;;) {
    var report = waitForReport();
    if (report == "done") {
        if (!--numWorkers) {
            print("All workers done!");
            break;
        }
    } else if (report == "error") {
        print("Test failed!");
        throw new Error("Test failed.");
    } else
        print("report: " + report);
}

for (var i = 0; i < 3; ++i) {
    if (memory[i] != 1)
        throw "Error: Bad value at memory[" + i + "]: " + memory[i];
}
for (var i = 3; i < memory.length; ++i) {
    if (memory[i] != 0)
        throw "Error: Bad value at memory[" + i + "]: " + memory[i];
}
print("Test passed!");