Function adjust_negative

ciphercore-base/src/ops/long_division.rs:239–312

(
    quotient: Node,
    remainder: Node,
    abs_divisor: Node,
    dividend_is_negative: Node,
    divisor_is_negative: Node,
)

}

fn adjust_negative(
    quotient: Node,
    remainder: Node,
    abs_divisor: Node,
    dividend_is_negative: Node,
    divisor_is_negative: Node,
) -> Result<(Node, Node)> {
    // We compute the quotient and remainder using the same logic as numpy's // and %.
    let g = quotient.get_graph();
    let result_is_negative = dividend_is_negative.add(divisor_is_negative.clone())?;
    let remainder_bits = pop_last_dim(remainder.get_type()?.get_dimensions()).1;
    let remainder_is_zero = unsqueeze(
        g.custom_op(
            CustomOperation::new(Equal {}),
            vec![
                remainder.clone(),
                g.zeros(array_type(vec![remainder_bits], BIT))?,
            ],
        )?,
        -1,
    )?;
    // quotient = (-quotient if remainder is 0 else -quotient-1)
    //            if result_is_negative else quotient
    let inverted_quotient = invert_bits(quotient.clone())?; // a.k.a (-quotient-1)
    let negative_quotient = add_one(inverted_quotient.clone())?;
    let quotient = g.custom_op(
        CustomOperation::new(Mux {}),
        vec![
            result_is_negative.clone(),
            g.custom_op(
                CustomOperation::new(Mux {}),
                vec![
                    remainder_is_zero.clone(),
                    negative_quotient,
                    inverted_quotient,
                ],
            )?,
            quotient,
        ],
    )?;
    // positive_remainder = 0 if remainder is 0
    //                      else abs(divisor) - remainder if result_is_negative else remainder
    let positive_remainder = g.custom_op(
        CustomOperation::new(Mux {}),
        vec![
            remainder_is_zero,
            remainder.clone(),
            g.custom_op(
                CustomOperation::new(Mux {}),
                vec![
                    result_is_negative,
                    g.custom_op(
                        CustomOperation::new(BinaryAdd {
                            overflow_bit: false,
                        }),
                        vec![abs_divisor, negative(remainder.clone())?],
                    )?,
                    remainder,