crypto_bigint/limb/
encoding.rs

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1//! Limb encoding
2
3use super::{Limb, Word};
4use crate::Encoding;
5
6impl Encoding for Limb {
7    const BIT_SIZE: usize = Self::BIT_SIZE;
8    const BYTE_SIZE: usize = Self::BYTE_SIZE;
9
10    #[cfg(target_pointer_width = "32")]
11    type Repr = [u8; 4];
12    #[cfg(target_pointer_width = "64")]
13    type Repr = [u8; 8];
14
15    #[inline]
16    fn from_be_bytes(bytes: Self::Repr) -> Self {
17        Limb(Word::from_be_bytes(bytes))
18    }
19
20    #[inline]
21    fn from_le_bytes(bytes: Self::Repr) -> Self {
22        Limb(Word::from_le_bytes(bytes))
23    }
24
25    #[inline]
26    fn to_be_bytes(&self) -> Self::Repr {
27        self.0.to_be_bytes()
28    }
29
30    #[inline]
31    fn to_le_bytes(&self) -> Self::Repr {
32        self.0.to_le_bytes()
33    }
34}
35
36#[cfg(test)]
37mod test {
38    use super::*;
39    use proptest::prelude::*;
40
41    prop_compose! {
42        fn limb()(inner in any::<Word>()) -> Limb {
43            Limb(inner)
44        }
45    }
46
47    proptest! {
48        #[test]
49        fn roundtrip(a in limb()) {
50            assert_eq!(a, Limb::from_be_bytes(a.to_be_bytes()));
51            assert_eq!(a, Limb::from_le_bytes(a.to_le_bytes()));
52        }
53    }
54
55    proptest! {
56        #[test]
57        fn reverse(a in limb()) {
58            let mut bytes = a.to_be_bytes();
59            bytes.reverse();
60            assert_eq!(a, Limb::from_le_bytes(bytes));
61
62            let mut bytes = a.to_le_bytes();
63            bytes.reverse();
64            assert_eq!(a, Limb::from_be_bytes(bytes));
65        }
66    }
67}
crypto_bigint/limb/encoding.rs

crypto_bigint/limb/
encoding.rs
