docs: function tinf_build_bits_base(bits, base, delta, first) {
    var i, sum;
  
    /* build bits table */
    for (i = 0; i < delta; ++i) bits[i] = 0;
    for (i = 0; i < 30 - delta; ++i) bits[i + delta] = i / delta | 0;
  
    /* build base table */
    for (sum = first, i = 0; i < 30; ++i) {
      base[i] = sum;
      sum += 1 << bits[i];
    }
  }