rust/crates/core_simd/src/round.rs

use crate::simd::intrinsics;
use crate::simd::{LaneCount, Simd, SupportedLaneCount};

macro_rules! implement {
    {
        $type:ty, $int_type:ty
    } => {
        #[cfg(feature = "std")]
        impl<const LANES: usize> Simd<$type, LANES>
        where
            LaneCount<LANES>: SupportedLaneCount,
        {
            /// Returns the smallest integer greater than or equal to each lane.
            #[must_use = "method returns a new vector and does not mutate the original value"]
            #[inline]
            pub fn ceil(self) -> Self {
                unsafe { intrinsics::simd_ceil(self) }
            }

            /// Returns the largest integer value less than or equal to each lane.
            #[must_use = "method returns a new vector and does not mutate the original value"]
            #[inline]
            pub fn floor(self) -> Self {
                unsafe { intrinsics::simd_floor(self) }
            }

            /// Rounds to the nearest integer value. Ties round toward zero.
            #[must_use = "method returns a new vector and does not mutate the original value"]
            #[inline]
            pub fn round(self) -> Self {
                unsafe { intrinsics::simd_round(self) }
            }

            /// Returns the floating point's integer value, with its fractional part removed.
            #[must_use = "method returns a new vector and does not mutate the original value"]
            #[inline]
            pub fn trunc(self) -> Self {
                unsafe { intrinsics::simd_trunc(self) }
            }

            /// Returns the floating point's fractional value, with its integer part removed.
            #[must_use = "method returns a new vector and does not mutate the original value"]
            #[inline]
            pub fn fract(self) -> Self {
                self - self.trunc()
            }
        }

        impl<const LANES: usize> Simd<$type, LANES>
        where
            LaneCount<LANES>: SupportedLaneCount,
        {
            /// Rounds toward zero and converts to the same-width integer type, assuming that
            /// the value is finite and fits in that type.
            ///
            /// # Safety
            /// The value must:
            ///
            /// * Not be NaN
            /// * Not be infinite
            /// * Be representable in the return type, after truncating off its fractional part
            #[inline]
            pub unsafe fn to_int_unchecked(self) -> Simd<$int_type, LANES> {
                unsafe { intrinsics::simd_cast(self) }
            }

            /// Creates a floating-point vector from an integer vector.  Rounds values that are
            /// not exactly representable.
            #[inline]
            pub fn round_from_int(value: Simd<$int_type, LANES>) -> Self {
                unsafe { intrinsics::simd_cast(value) }
            }
        }
    }
}

implement! { f32, i32 }
implement! { f64, i64 }