code: function fnv_mix(a) {
      a += a << 13;
      a ^= a >>> 7;
      a += a << 3;
      a ^= a >>> 17;
      a += a << 5;
      return a & 0xffffffff;
    }
docs: See https://web.archive.org/web/20131019013225/http://home.comcast.net/~bretm/hash/6.html