halftime 0.1.1

HalftimeHash: almost-universal hashing for long strings
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
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132

//! Runtime CPU feature detection (x86): AVX-512 > AVX2×2 > SSE2×4 > scalar repeat.

use universal_hash::{UhfClosure, UniversalHash, common::BlockSizeUser};

use crate::backend::{Absorb, soft};
use crate::entropy::Entropy;
use crate::variant::HalftimeVariant;

cpufeatures::new!(avx2_token, "avx2");
cpufeatures::new!(avx512f_token, "avx512f");
cpufeatures::new!(sse2_token, "sse2");

macro_rules! define_autodetect {
    ($mod_name:ident, $v:ty, $avx512:ty, $avx2r8:ty, $sse2r8:ty, $repeat8:ty) => {
        pub(crate) mod $mod_name {
            use super::*;

            pub(crate) enum Inner {
                Avx512($avx512),
                Avx2Repeat8($avx2r8),
                Sse2Repeat8($sse2r8),
                Repeat8($repeat8),
            }

            pub(crate) struct State {
                inner: Inner,
            }

            impl Clone for State {
                fn clone(&self) -> Self {
                    Self {
                        inner: match &self.inner {
                            Inner::Avx512(s) => Inner::Avx512(s.clone()),
                            Inner::Avx2Repeat8(s) => Inner::Avx2Repeat8(s.clone()),
                            Inner::Sse2Repeat8(s) => Inner::Sse2Repeat8(s.clone()),
                            Inner::Repeat8(s) => Inner::Repeat8(s.clone()),
                        },
                    }
                }
            }

            impl BlockSizeUser for State {
                type BlockSize = <$v as HalftimeVariant>::TagSize;
            }

            impl State {
                pub(crate) fn new(key: &[u8; 32]) -> Self {
                    let (_avx512_token, has_avx512) = avx512f_token::init_get();
                    let (_avx2_token, has_avx2) = avx2_token::init_get();
                    let (_sse2_token, has_sse2) = sse2_token::init_get();
                    let inner = if has_avx512 {
                        Inner::Avx512(<$avx512>::new(key))
                    } else if has_avx2 {
                        Inner::Avx2Repeat8(<$avx2r8>::new(key))
                    } else if has_sse2 {
                        Inner::Sse2Repeat8(<$sse2r8>::new(key))
                    } else {
                        Inner::Repeat8(<$repeat8>::new(key))
                    };
                    Self { inner }
                }

                pub(crate) fn from_entropy(entropy: Entropy) -> Self {
                    let (_avx512_token, has_avx512) = avx512f_token::init_get();
                    let (_avx2_token, has_avx2) = avx2_token::init_get();
                    let (_sse2_token, has_sse2) = sse2_token::init_get();
                    let inner = if has_avx512 {
                        Inner::Avx512(<$avx512>::from_entropy(entropy))
                    } else if has_avx2 {
                        Inner::Avx2Repeat8(<$avx2r8>::from_entropy(entropy.clone()))
                    } else if has_sse2 {
                        Inner::Sse2Repeat8(<$sse2r8>::from_entropy(entropy.clone()))
                    } else {
                        Inner::Repeat8(<$repeat8>::from_entropy(entropy))
                    };
                    Self { inner }
                }
            }

            impl Absorb for State {
                fn absorb(&mut self, data: &[u8]) {
                    match &mut self.inner {
                        Inner::Avx512(s) => s.absorb(data),
                        Inner::Avx2Repeat8(s) => s.absorb(data),
                        Inner::Sse2Repeat8(s) => s.absorb(data),
                        Inner::Repeat8(s) => s.absorb(data),
                    }
                }
            }

            impl UniversalHash for State {
                fn update_with_backend(&mut self, f: impl UhfClosure<BlockSize = Self::BlockSize>) {
                    match &mut self.inner {
                        Inner::Avx512(s) => f.call(s),
                        Inner::Avx2Repeat8(s) => f.call(s),
                        Inner::Sse2Repeat8(s) => f.call(s),
                        Inner::Repeat8(s) => f.call(s),
                    }
                }

                fn finalize(self) -> universal_hash::array::Array<u8, Self::BlockSize> {
                    match self.inner {
                        Inner::Avx512(s) => s.finalize(),
                        Inner::Avx2Repeat8(s) => s.finalize(),
                        Inner::Sse2Repeat8(s) => s.finalize(),
                        Inner::Repeat8(s) => s.finalize(),
                    }
                }
            }
        }
    };
}

macro_rules! autodetect_variants {
    ($($mod:ident, $v:ty, $avx512:ty, $avx2:ty, $sse2:ty, $r8:ty;)*) => {
        $(define_autodetect!($mod, $v, $avx512, $avx2, $sse2, $r8);)*
    };
}

use crate::variant::{Hh16, Hh24, Hh32, Hh40};

autodetect_variants! {
    ad16, Hh16, soft::Avx512State16, soft::Avx2Repeat8State16, soft::Sse2Repeat8State16, soft::State16;
    ad24, Hh24, soft::Avx512State24, soft::Avx2Repeat8State24, soft::Sse2Repeat8State24, soft::State24;
    ad32, Hh32, soft::Avx512State32, soft::Avx2Repeat8State32, soft::Sse2Repeat8State32, soft::State32;
    ad40, Hh40, soft::Avx512State40, soft::Avx2Repeat8State40, soft::Sse2Repeat8State40, soft::State40;
}

pub(crate) use ad16::State as State16;
pub(crate) use ad24::State as State24;
pub(crate) use ad32::State as State32;
pub(crate) use ad40::State as State40;