Function memrchr3 

pub fn memrchr3<'a>(
    needle1: u8,
    needle2: u8,
    needle3: u8,
    haystacks: impl IntoIterator<Item = &'a [u8]>,
) -> Option<usize>

Variant of [memchr::memrchr3()] for a discontiguous haystack. See memrchr() for more info.