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use super::block::{Block, BLOCK_LEN};
#[cfg(not(target_arch = "aarch64"))]
pub fn shift_full_blocks<F>(in_out: &mut [u8], in_prefix_len: usize, mut transform: F)
where
F: FnMut(&[u8; BLOCK_LEN]) -> Block,
{
use core::convert::TryFrom;
let in_out_len = in_out.len().checked_sub(in_prefix_len).unwrap();
for i in (0..in_out_len).step_by(BLOCK_LEN) {
let block = {
let input =
<&[u8; BLOCK_LEN]>::try_from(&in_out[(in_prefix_len + i)..][..BLOCK_LEN]).unwrap();
transform(input)
};
let output = <&mut [u8; BLOCK_LEN]>::try_from(&mut in_out[i..][..BLOCK_LEN]).unwrap();
*output = *block.as_ref();
}
}
pub fn shift_partial<F>((in_prefix_len, in_out): (usize, &mut [u8]), transform: F)
where
F: FnOnce(&[u8]) -> Block,
{
let (block, in_out_len) = {
let input = &in_out[in_prefix_len..];
let in_out_len = input.len();
if in_out_len == 0 {
return;
}
debug_assert!(in_out_len < BLOCK_LEN);
(transform(input), in_out_len)
};
in_out[..in_out_len].copy_from_slice(&block.as_ref()[..in_out_len]);
}