toFixedPointValue method

Implementation

FixedPointValue toFixedPointValue() {
  final exact = toScaledBigInt();
  var significand = exact.significand;
  var exponent = exact.exponent;
  if (significand == BigInt.zero) {
    return FixedPointValue.populatorWithSignedness(
            integerWidth: 0, fractionWidth: 0)
        .ofScaledBigInt(BigInt.zero, 0);
  }
  while (significand.isEven) {
    significand >>= 1;
    exponent++;
  }

  final fractionWidth = max(0, -exponent);
  final scaled = exponent > 0 ? significand << exponent : significand;
  final requiredSignedWidth = scaled.isNegative
      ? (scaled.abs() - BigInt.one).bitLength + 1
      : scaled.bitLength + 1;
  final totalWidth = max(fractionWidth + 1, requiredSignedWidth);
  return FixedPointValue.populatorWithSignedness(
          integerWidth: totalWidth - fractionWidth - 1,
          fractionWidth: fractionWidth)
      .ofScaledBigInt(significand, exponent);
}