mpzjs/examples/gen-threads.js

Arbitrary-precision integer arithmetic using libgmp

const {Worker, isMainThread, workerData} = require('worker_threads');
const os = require('os');
const assert = require('assert');
const MPZ = require('../');

if (isMainThread) {
    (async function main() {
        const threads = new Promise(resolve => {
            const size = os.cpus().length * 2;
            let wait = size;

            for (let i = 0; i < size; i++) {
                const worker = new Worker(__filename, {workerData: i});

                worker.on('exit', () => {
                    wait--;
                    if (wait === 0) {
                        resolve();
                    }
                });
            }
        });

        work('main');
        await threads;
    })();
} else {
    work(workerData);
}

function work(id) {
    const q = MPZ(2).pow(159).add(1).rand(MPZ(2).pow(160)).nextPrime();
    const L = 512 + 64 * Math.floor(Math.random() * 8);

    let p;
    do {
        const X = MPZ(2).pow(L - 1).add(1).rand(MPZ(2).pow(L));
        const c = X.mod(q.mul(2));
        p = X.sub(c.sub(1)); // p is congruent to 1 % 2q somehow!
    } while (p.lt(MPZ(2).pow(L - 1)) || p.probPrime(50) === false);

    assert.ok(q.gt(MPZ(2).pow(159)), 'q > 2**159');
    assert.ok(q.lt(MPZ(2).pow(160)), 'q < 2**160');
    assert.ok(p.gt(MPZ(2).pow(L - 1)), 'p > 2**(L-1)');
    assert.ok(q.lt(MPZ(2).pow(L)), 'p < 2**L');
    assert.ok(q.mul(p.sub(1).div(q)).add(1).eq(p), 'q divides p - 1');

    assert.ok(p.probPrime(50), 'p is not prime!');
    assert.ok(q.probPrime(50), 'q is not prime!');

    console.dir({ id, p : p.toString(), q : q.toString() });
}