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use num::arithmetic::traits::{
ModPowerOf2Mul, ModPowerOf2MulAssign, ModPowerOf2Square, ModPowerOf2SquareAssign,
};
macro_rules! impl_mod_power_of_2_square {
($t:ident) => {
impl ModPowerOf2Square for $t {
type Output = $t;
/// Squares a number modulo another number $2^k$. Assumes the input is already reduced
/// modulo $2^k$.
///
/// $f(x, k) = y$, where $x, y < 2^k$ and $x^2 \equiv y \mod 2^k$.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Panics
/// Panics if `pow` is greater than `Self::WIDTH`.
///
/// # Examples
/// See [here](super::mod_power_of_2_square#mod_power_of_2_square).
#[inline]
fn mod_power_of_2_square(self, pow: u64) -> $t {
self.mod_power_of_2_mul(self, pow)
}
}
impl ModPowerOf2SquareAssign for $t {
/// Squares a number modulo another number $2^k$, in place. Assumes the input is
/// already reduced modulo $2^k$.
///
/// $x \gets y$, where $x, y < 2^k$ and $x^2 \equiv y \mod 2^k$.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Panics
/// Panics if `pow` is greater than `Self::WIDTH`.
///
/// # Examples
/// See [here](super::mod_power_of_2_square#mod_power_of_2_square_assign).
#[inline]
fn mod_power_of_2_square_assign(&mut self, pow: u64) {
self.mod_power_of_2_mul_assign(*self, pow);
}
}
};
}
apply_to_unsigneds!(impl_mod_power_of_2_square);