ring 0.17.11

// Copyright 2018 Brian Smith.
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
// SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
// OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
// CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

#[cfg(target_arch = "x86")]
pub fn shift_full_blocks<const BLOCK_LEN: usize>(
    in_out: super::overlapping::Overlapping<'_, u8>,
    mut transform: impl FnMut(&[u8; BLOCK_LEN]) -> [u8; BLOCK_LEN],
) {
    let (in_out, src) = in_out.into_slice_src_mut();
    let in_out_len = in_out[src.clone()].len();

    for i in (0..in_out_len).step_by(BLOCK_LEN) {
        let block = {
            let input =
                <&[u8; BLOCK_LEN]>::try_from(&in_out[(src.start + i)..][..BLOCK_LEN]).unwrap();
            transform(input)
        };
        let output = <&mut [u8; BLOCK_LEN]>::try_from(&mut in_out[i..][..BLOCK_LEN]).unwrap();
        *output = block;
    }
}