malachite_base/num/arithmetic/
mod_square.rs

1// Copyright © 2025 Mikhail Hogrefe
2//
3// This file is part of Malachite.
4//
5// Malachite is free software: you can redistribute it and/or modify it under the terms of the GNU
6// Lesser General Public License (LGPL) as published by the Free Software Foundation; either version
7// 3 of the License, or (at your option) any later version. See <https://www.gnu.org/licenses/>.
8
9use crate::num::arithmetic::traits::{
10    ModPow, ModPowAssign, ModPowPrecomputed, ModPowPrecomputedAssign, ModSquare, ModSquareAssign,
11    ModSquarePrecomputed, ModSquarePrecomputedAssign,
12};
13
14macro_rules! impl_mod_square {
15    ($t:ident) => {
16        impl ModSquare for $t {
17            type Output = $t;
18
19            /// Squares a number modulo another number $m$. The input must be already reduced modulo
20            /// $m$.
21            ///
22            /// $f(x, m) = y$, where $x, y < m$ and $x^2 \equiv y \mod m$.
23            ///
24            /// # Worst-case complexity
25            /// Constant time and additional memory.
26            ///
27            /// # Panics
28            /// Panics if `self` is greater than or equal to `m`.
29            ///
30            /// # Examples
31            /// See [here](super::mod_square#mod_square).
32            #[inline]
33            fn mod_square(self, m: $t) -> $t {
34                self.mod_pow(2, m)
35            }
36        }
37
38        impl ModSquareAssign for $t {
39            /// Squares a number modulo another number $m$, in place. The input must be already
40            /// reduced modulo $m$.
41            ///
42            /// $x \gets y$, where $x, y < m$ and $x^2 \equiv y \mod m$.
43            ///
44            /// # Worst-case complexity
45            /// Constant time and additional memory.
46            ///
47            /// # Panics
48            /// Panics if `self` is greater than or equal to `m`.
49            ///
50            /// # Examples
51            /// See [here](super::mod_square#mod_square_assign).
52            #[inline]
53            fn mod_square_assign(&mut self, m: $t) {
54                self.mod_pow_assign(2, m);
55            }
56        }
57
58        impl ModSquarePrecomputed<u64, $t> for $t {
59            /// Squares a number modulo another number $m$. The input must be already reduced modulo
60            /// $m$.
61            ///
62            /// Some precomputed data is provided; this speeds up computations involving several
63            /// modular squarings with the same modulus. The precomputed data should be obtained
64            /// using [`precompute_mod_pow_data`](super::traits::ModPowPrecomputed).
65            ///
66            /// # Worst-case complexity
67            /// Constant time and additional memory.
68            ///
69            /// # Panics
70            /// Panics if `self` is greater than or equal to `m`.
71            ///
72            /// # Examples
73            /// See [here](super::mod_square#mod_square_precomputed).
74            #[inline]
75            fn mod_square_precomputed(self, m: $t, data: &Self::Data) -> Self::Output {
76                self.mod_pow_precomputed(2, m, data)
77            }
78        }
79
80        impl ModSquarePrecomputedAssign<u64, $t> for $t {
81            /// Squares a number modulo another number $m$, in place. The input must be already
82            /// reduced modulo $m$.
83            ///
84            /// Some precomputed data is provided; this speeds up computations involving several
85            /// modular squarings with the same modulus. The precomputed data should be obtained
86            /// using [`precompute_mod_pow_data`](super::traits::ModPowPrecomputed).
87            ///
88            /// # Worst-case complexity
89            /// Constant time and additional memory.
90            ///
91            /// # Panics
92            /// Panics if `self` is greater than or equal to `m`.
93            ///
94            /// # Examples
95            /// See [here](super::mod_square#mod_square_precomputed_assign).
96            #[inline]
97            fn mod_square_precomputed_assign(&mut self, m: $t, data: &Self::Data) {
98                self.mod_pow_precomputed_assign(2, m, data);
99            }
100        }
101    };
102}
103apply_to_unsigneds!(impl_mod_square);
malachite_base/num/arithmetic/mod_square.rs

malachite_base/num/arithmetic/
mod_square.rs
