crypto_bigint/uint/
split.rs

1use crate::{Limb, Uint};
2
3/// Split this number in half, returning its high and low components
4/// respectively.
5#[inline]
6pub(crate) const fn split_mixed<const L: usize, const H: usize, const O: usize>(
7    n: &Uint<O>,
8) -> (Uint<H>, Uint<L>) {
9    let top = L + H;
10    let top = if top < O { top } else { O };
11    let mut lo = [Limb::ZERO; L];
12    let mut hi = [Limb::ZERO; H];
13    let mut i = 0;
14
15    while i < top {
16        if i < L {
17            lo[i] = n.limbs[i];
18        } else {
19            hi[i - L] = n.limbs[i];
20        }
21        i += 1;
22    }
23
24    (Uint { limbs: hi }, Uint { limbs: lo })
25}
26
27#[cfg(test)]
28mod tests {
29    use crate::{U128, U64};
30
31    #[test]
32    fn split() {
33        let (hi, lo) = U128::from_be_hex("00112233445566778899aabbccddeeff").split();
34        assert_eq!(hi, U64::from_u64(0x0011223344556677));
35        assert_eq!(lo, U64::from_u64(0x8899aabbccddeeff));
36    }
37}
crypto_bigint/uint/split.rs

crypto_bigint/uint/
split.rs
