mincdc 0.1.0

A very simple yet efficient content-defined chunking algorithm.
Documentation 
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pub fn argmin_u32_overlapping_hashed<const SHOULD_HASH: bool>(
    bytes: &[u8],
    multiplier: u32,
    addend: u32,
) -> usize {
    let mut min_idx = 0;
    let mut min_val = u32::MAX;

    if bytes.len() < 4 {
        return 0;
    }

    for (i, window) in bytes.windows(4).enumerate() {
        let mut v = u32::from_le_bytes(window.try_into().unwrap());
        if SHOULD_HASH {
            v = v.wrapping_mul(multiplier);
            v = v.wrapping_add(addend);
        }
        if v < min_val {
            min_val = v;
            min_idx = i;
        }
    }

    min_idx
}

#[inline(always)]
#[allow(dead_code)]
pub fn argmin_u32_overlapping_hashed_four<const SHOULD_HASH: bool>(
    bytes: &[u8],
    multiplier: u32,
    addend: u32,
) -> usize {
    assert!(bytes.len() >= 7);
    (0..4)
        .min_by_key(|i| {
            let substr = &bytes[*i..*i + 4];
            let mut v = u32::from_le_bytes(substr.try_into().unwrap());
            if SHOULD_HASH {
                v = v.wrapping_mul(multiplier);
                v = v.wrapping_add(addend);
            }
            v
        })
        .unwrap()
}