faster 0.5.2

Explicit SIMD for humans
// This file is part of faster, the SIMD library for humans.
// Copyright 2017 Adam Niederer <adam.niederer@gmail.com>

// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.

pub trait Transmute {
    type i8s;
    type u8s;
    type i16s;
    type u16s;
    type i32s;
    type u32s;
    type f32s;
    type i64s;
    type u64s;
    type f64s;

    fn be_i8s(&self) -> Self::i8s;
    fn be_u8s(&self) -> Self::u8s;
    fn be_i16s(&self) -> Self::i16s;
    fn be_u16s(&self) -> Self::u16s;
    fn be_i32s(&self) -> Self::i32s;
    fn be_u32s(&self) -> Self::u32s;
    // TODO: Remove possibility of signalling NaNs
    unsafe fn be_f32s_unchecked(&self) -> Self::f32s;
    fn be_i64s(&self) -> Self::i64s;
    fn be_u64s(&self) -> Self::u64s;
    // TODO: Remove possibility of signalling NaNs
    unsafe fn be_f64s_unchecked(&self) -> Self::f64s;
}

macro_rules! impl_packed_transmute {
    ($($t:ty,)* ... $u8s:ty, $i8s:ty, $u16s:ty, $i16s:ty, $u32s:ty, $i32s:ty,
     $f32s:ty, $u64s:ty, $i64s:ty, $f64s:ty, $feat:expr, $nfeat:expr) => (
        $(
            impl Transmute for $t {
                type i8s = $i8s;
                type u8s = $u8s;
                type i16s = $i16s;
                type u16s = $u16s;
                type i32s = $i32s;
                type u32s = $u32s;
                type f32s = $f32s;
                type i64s = $i64s;
                type u64s = $u64s;
                type f64s = $f64s;

                #[inline(always)]
                fn be_i8s(&self) -> Self::i8s {
                    unsafe { transmute::<Self, Self::i8s>(*self) }
                }

                #[inline(always)]
                fn be_u8s(&self) -> Self::u8s {
                    unsafe { transmute::<Self, Self::u8s>(*self) }
                }

                #[inline(always)]
                fn be_i16s(&self) -> Self::i16s {
                    unsafe { transmute::<Self, Self::i16s>(*self) }
                }

                #[inline(always)]
                fn be_u16s(&self) -> Self::u16s {
                    unsafe { transmute::<Self, Self::u16s>(*self) }
                }

                #[inline(always)]
                fn be_i32s(&self) -> Self::i32s {
                    unsafe { transmute::<Self, Self::i32s>(*self) }
                }

                #[inline(always)]
                fn be_u32s(&self) -> Self::u32s {
                    unsafe { transmute::<Self, Self::u32s>(*self) }
                }

                #[inline(always)]
                unsafe fn be_f32s_unchecked(&self) -> Self::f32s {
                    transmute::<Self, Self::f32s>(*self)
                }

                #[inline(always)]
                fn be_i64s(&self) -> Self::i64s {
                    unsafe { transmute::<Self, Self::i64s>(*self) }
                }

                #[inline(always)]
                fn be_u64s(&self) -> Self::u64s {
                    unsafe { transmute::<Self, Self::u64s>(*self) }
                }

                #[inline(always)]
                unsafe fn be_f64s_unchecked(&self) -> Self::f64s {
                    transmute::<Self, Self::f64s>(*self)
                }
            }
        )*
    );
}

#[cfg(test)]
mod tests {
    use crate::prelude::*;

    macro_rules! test_transmute {
        ($name:ident, $val:expr, $xmute:ident) => (
            #[test]
            fn $name() {
                #![allow(unused_unsafe)]
                assert_eq!(unsafe { $val.be_i8s().$xmute() }, $val);
                assert_eq!(unsafe { $val.be_u8s().$xmute() }, $val);
                assert_eq!(unsafe { $val.be_i16s().$xmute() }, $val);
                assert_eq!(unsafe { $val.be_u16s().$xmute() }, $val);
                assert_eq!(unsafe { $val.be_i32s().$xmute() }, $val);
                assert_eq!(unsafe { $val.be_u32s().$xmute() }, $val);
                assert_eq!(unsafe { $val.be_i64s().$xmute() }, $val);
                assert_eq!(unsafe { $val.be_u64s().$xmute() }, $val);
            }
        )
    }

    test_transmute!(transmute_u8s, u8s(1), be_u8s);
    test_transmute!(transmute_i8s, i8s(1), be_i8s);
    test_transmute!(transmute_u16s, u16s(1), be_u16s);
    test_transmute!(transmute_i16s, i16s(1), be_i16s);
    test_transmute!(transmute_u32s, u32s(1), be_u32s);
    test_transmute!(transmute_i32s, i32s(1), be_i32s);
    test_transmute!(transmute_f32s, f32s(1.0), be_f32s_unchecked);
    test_transmute!(transmute_u64s, u64s(1), be_u64s);
    test_transmute!(transmute_i64s, i64s(1), be_i64s);
    test_transmute!(transmute_f64s, f64s(1.0), be_f64s_unchecked);
}