crypto-bigint 0.7.5

Pure Rust implementation of a big integer library which has been designed from the ground-up for use in cryptographic applications. Provides constant-time, no_std-friendly implementations of modern formulas using const generics.
Documentation 
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//! [`BoxedUint`] bitwise OR operations.

use crate::{BitOr, BitOrAssign, BoxedUint, CtOption, Limb};

impl BoxedUint {
    /// Computes bitwise `a | b`.
    #[inline(always)]
    #[must_use]
    pub fn bitor(&self, rhs: &Self) -> Self {
        Self::map_limbs(self, rhs, Limb::bitor)
    }

    /// Perform wrapping bitwise `OR`.
    ///
    /// There's no way wrapping could ever happen.
    /// This function exists so that all operations are accounted for in the wrapping operations
    #[must_use]
    pub fn wrapping_or(&self, rhs: &Self) -> Self {
        self.bitor(rhs)
    }

    /// Perform checked bitwise `OR`, returning a [`CtOption`] which `is_some` always
    #[must_use]
    pub fn checked_or(&self, rhs: &Self) -> CtOption<Self> {
        CtOption::some(self.bitor(rhs))
    }
}

impl BitOr for BoxedUint {
    type Output = Self;

    fn bitor(self, rhs: Self) -> BoxedUint {
        self.bitor(&rhs)
    }
}

impl BitOr<&BoxedUint> for BoxedUint {
    type Output = BoxedUint;

    #[allow(clippy::needless_borrow)]
    fn bitor(self, rhs: &BoxedUint) -> BoxedUint {
        (&self).bitor(rhs)
    }
}

impl BitOr<BoxedUint> for &BoxedUint {
    type Output = BoxedUint;

    fn bitor(self, rhs: BoxedUint) -> BoxedUint {
        self.bitor(&rhs)
    }
}

impl BitOr<&BoxedUint> for &BoxedUint {
    type Output = BoxedUint;

    fn bitor(self, rhs: &BoxedUint) -> BoxedUint {
        self.bitor(rhs)
    }
}

impl BitOrAssign for BoxedUint {
    fn bitor_assign(&mut self, other: Self) {
        Self::bitor_assign(self, &other);
    }
}

impl BitOrAssign<&BoxedUint> for BoxedUint {
    fn bitor_assign(&mut self, other: &Self) {
        if other.limbs.len() > self.limbs.len() {
            self.resize_in_place_unchecked(other.bits_precision());
        }

        for (a, b) in self.limbs.iter_mut().zip(other.limbs.iter()) {
            *a |= *b;
        }
    }
}

#[cfg(test)]
mod tests {
    use crate::{BitOrAssign, BoxedUint, Limb};

    #[test]
    fn bitor_assign_preserves_wider_rhs_limbs() {
        let mut lhs = BoxedUint::zero_with_precision(Limb::BITS);
        let rhs = BoxedUint::max(Limb::BITS * 2);
        let expected = lhs.bitor(&rhs);

        lhs.bitor_assign(&rhs);

        assert_eq!(lhs, expected);
    }
}