axhash-core 0.9.0

Platform-agnostic AxHash core for Rust with no_std compatibility.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74

use crate::backend::finalize_vector;
use crate::constants::{SECRET, STRIPE_SECRET};
use crate::memory::r_128;
use core::arch::aarch64::*;

#[target_feature(enable = "neon", enable = "aes")]
#[inline]
unsafe fn process_128_block_aarch64(
    ptr: *const u8,
    v0: &mut uint8x16_t, v1: &mut uint8x16_t, v2: &mut uint8x16_t, v3: &mut uint8x16_t,
    v4: &mut uint8x16_t, v5: &mut uint8x16_t, v6: &mut uint8x16_t, v7: &mut uint8x16_t,
) {
    let d0 = unsafe { r_128(ptr) };
    let d1 = unsafe { r_128(ptr.add(16)) };
    let d2 = unsafe { r_128(ptr.add(32)) };
    let d3 = unsafe { r_128(ptr.add(48)) };
    let d4 = unsafe { r_128(ptr.add(64)) };
    let d5 = unsafe { r_128(ptr.add(80)) };
    let d6 = unsafe { r_128(ptr.add(96)) };
    let d7 = unsafe { r_128(ptr.add(112)) };

    *v0 = vaesmcq_u8(vaeseq_u8(*v0, d0));
    *v1 = vaesmcq_u8(vaeseq_u8(*v1, d1));
    *v2 = vaesmcq_u8(vaeseq_u8(*v2, d2));
    *v3 = vaesmcq_u8(vaeseq_u8(*v3, d3));
    *v4 = vaesmcq_u8(vaeseq_u8(*v4, d4));
    *v5 = vaesmcq_u8(vaeseq_u8(*v5, d5));
    *v6 = vaesmcq_u8(vaeseq_u8(*v6, d6));
    *v7 = vaesmcq_u8(vaeseq_u8(*v7, d7));

    *v1 = veorq_u8(*v1, *v0);
    *v3 = veorq_u8(*v3, *v2);
    *v5 = veorq_u8(*v5, *v4);
    *v7 = veorq_u8(*v7, *v6);
}

#[target_feature(enable = "neon", enable = "aes")]
pub(crate) unsafe fn hash_bytes_long(ptr: *const u8, len: usize, acc: u64) -> u64 {
    let mut v0 = vreinterpretq_u8_u64(vdupq_n_u64(SECRET[0] ^ acc));
    let mut v1 = vreinterpretq_u8_u64(vdupq_n_u64(STRIPE_SECRET[0] ^ acc));
    let mut v2 = vreinterpretq_u8_u64(vdupq_n_u64(SECRET[1] ^ acc));
    let mut v3 = vreinterpretq_u8_u64(vdupq_n_u64(STRIPE_SECRET[1] ^ acc));
    let mut v4 = vreinterpretq_u8_u64(vdupq_n_u64(SECRET[2] ^ acc));
    let mut v5 = vreinterpretq_u8_u64(vdupq_n_u64(STRIPE_SECRET[2] ^ acc));
    let mut v6 = vreinterpretq_u8_u64(vdupq_n_u64(SECRET[3] ^ acc));
    let mut v7 = vreinterpretq_u8_u64(vdupq_n_u64(STRIPE_SECRET[3] ^ acc));

    let mut offset = 0usize;
    while offset + 128 <= len {
        unsafe {
            process_128_block_aarch64(
                ptr.add(offset), &mut v0, &mut v1, &mut v2, &mut v3,
                &mut v4, &mut v5, &mut v6, &mut v7,
            );
        }
        offset += 128;
    }
    unsafe {
        process_128_block_aarch64(
            ptr.add(len - 128), &mut v0, &mut v1, &mut v2, &mut v3,
            &mut v4, &mut v5, &mut v6, &mut v7,
        );
    }

    let sum0 = veorq_u8(veorq_u8(v0, v2), veorq_u8(v4, v6));
    let sum1 = veorq_u8(veorq_u8(v1, v3), veorq_u8(v5, v7));
    let final_vec = veorq_u8(sum0, sum1);

    let final_u64x2 = vreinterpretq_u64_u8(final_vec);
    let lo = vgetq_lane_u64(final_u64x2, 0);
    let hi = vgetq_lane_u64(final_u64x2, 1);

    finalize_vector(lo, hi, len)
}