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// Copyright © 2026 Mikhail Hogrefe
//
// This file is part of Malachite.
//
// Malachite is free software: you can redistribute it and/or modify it under the terms of the GNU
// Lesser General Public License (LGPL) as published by the Free Software Foundation; either version
// 3 of the License, or (at your option) any later version. See <https://www.gnu.org/licenses/>.
use crate::num::arithmetic::mul_add_mul::{
Wide, mul_add_mul_wide_signed, mul_add_mul_wide_unsigned,
};
use crate::num::arithmetic::traits::{
OverflowingMulAddMul, OverflowingMulAddMulAssign, WrappingMulAddMul,
};
macro_rules! impl_overflowing_mul_add_mul {
($t:ident, $wide:ident) => {
impl OverflowingMulAddMul for $t {
type Output = $t;
/// Adds the products of two pairs of numbers.
///
/// Returns a tuple of the result along with a boolean indicating whether an arithmetic
/// overflow occurred. If an overflow occurred, then the wrapped result is returned.
///
/// $$
/// f(x, y, z, w) = (xy + zw \\mod 2^W, m),
/// $$
/// where $W$ is `Self::WIDTH` and $m$ is true if and only if $xy + zw$ is not
/// representable.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// See [here](super::overflowing_mul_add_mul#overflowing_mul_add_mul).
#[inline]
fn overflowing_mul_add_mul(self, y: $t, z: $t, w: $t) -> ($t, bool) {
(
self.wrapping_mul_add_mul(y, z, w),
!matches!($wide(self, y, z, w, false), Wide::Fits(_)),
)
}
}
impl OverflowingMulAddMulAssign for $t {
/// Adds the products of two pairs of numbers, in place.
///
/// Returns a boolean indicating whether an arithmetic overflow occurred. If an overflow
/// occurred, then the wrapped result is assigned.
///
/// $$
/// x \\gets xy + zw \\mod 2^W,
/// $$
/// where $W$ is `Self::WIDTH`; the return value is true if and only if $xy + zw$ is not
/// representable.
///
/// # Worst-case complexity
/// Constant time and additional memory.
///
/// # Examples
/// See [here](super::overflowing_mul_add_mul#overflowing_mul_add_mul_assign).
#[inline]
fn overflowing_mul_add_mul_assign(&mut self, y: $t, z: $t, w: $t) -> bool {
let (result, overflow) = self.overflowing_mul_add_mul(y, z, w);
*self = result;
overflow
}
}
};
}
macro_rules! impl_overflowing_mul_add_mul_unsigned {
($t:ident) => {
impl_overflowing_mul_add_mul!($t, mul_add_mul_wide_unsigned);
};
}
apply_to_unsigneds!(impl_overflowing_mul_add_mul_unsigned);
macro_rules! impl_overflowing_mul_add_mul_signed {
($t:ident) => {
impl_overflowing_mul_add_mul!($t, mul_add_mul_wide_signed);
};
}
apply_to_signeds!(impl_overflowing_mul_add_mul_signed);