// Thanks: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference // /Global_Objects/Math/imul 'use strict'; module.exports = function (x, y) { var xh = (x >>> 16) & 0xffff, xl = x & 0xffff , yh = (y >>> 16) & 0xffff, yl = y & 0xffff; // the shift by 0 fixes the sign on the high part // the final |0 converts the unsigned value into a signed value return ((xl * yl) + (((xh * yl + xl * yh) << 16) >>> 0) | 0); };