Function sha::sha256::ops::expand_round_x4

pub fn expand_round_x4(w: &mut [u32; 16], t: usize)

This function can be easily implemented with Intel SHA intruction set extensions.

{
    let temp = sha256load(work[2], work[3]);
    sha256msg2(sha256msg1(work[0], work[1]) + temp, work[3])
}