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``````use crate::simd::intrinsics;
use crate::simd::{LaneCount, Mask, MaskElement, Simd, SimdElement, SupportedLaneCount};

impl<T, const LANES: usize> Mask<T, LANES>
where
T: MaskElement,
LaneCount<LANES>: SupportedLaneCount,
{
/// Choose lanes from two vectors.
///
/// For each lane in the mask, choose the corresponding lane from `true_values` if
/// that lane mask is true, and `false_values` if that lane mask is false.
///
/// # Examples
/// ```
/// # #![feature(portable_simd)]
/// # use core::simd::{Simd, Mask};
/// let a = Simd::from_array([0, 1, 2, 3]);
/// let b = Simd::from_array([4, 5, 6, 7]);
/// let mask = Mask::from_array([true, false, false, true]);
/// let c = mask.select(a, b);
/// assert_eq!(c.to_array(), [0, 5, 6, 3]);
/// ```
#[inline]
#[must_use = "method returns a new vector and does not mutate the original inputs"]
pub fn select<U>(
self,
true_values: Simd<U, LANES>,
false_values: Simd<U, LANES>,
) -> Simd<U, LANES>
where
U: SimdElement<Mask = T>,
{
// Safety: The mask has been cast to a vector of integers,
// and the operands to select between are vectors of the same type and length.
unsafe { intrinsics::simd_select(self.to_int(), true_values, false_values) }
}

/// Choose lanes from two masks.
///
/// For each lane in the mask, choose the corresponding lane from `true_values` if
/// that lane mask is true, and `false_values` if that lane mask is false.
///
/// # Examples
/// ```
/// # #![feature(portable_simd)]
/// # use core::simd::Mask;
/// let a = Mask::<i32, 4>::from_array([true, true, false, false]);
/// let b = Mask::<i32, 4>::from_array([false, false, true, true]);
/// let mask = Mask::<i32, 4>::from_array([true, false, false, true]);
/// let c = mask.select_mask(a, b);
/// assert_eq!(c.to_array(), [true, false, true, false]);
/// ```
#[inline]
#[must_use = "method returns a new mask and does not mutate the original inputs"]
pub fn select_mask(self, true_values: Self, false_values: Self) -> Self {
self & true_values | !self & false_values
}
}
``````