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    #![allow(dead_code)]

    use std::arch::x86_64::*;
    use std::fmt;
    use std::mem;

    /// A builder for SSSE3 empowered vectors.
    ///
    /// This builder represents a receipt that the SSSE3 target feature is enabled
    /// on the currently running CPU. Namely, the only way to get a value of this
    /// type is if the SSSE3 feature is enabled.
    ///
    /// This type can then be used to build vector types that use SSSE3 features
    /// safely.
    #[derive(Clone, Copy, Debug)]
    pub struct SSSE3VectorBuilder(());

    impl SSSE3VectorBuilder {
        /// Create a new SSSE3 vector builder.
        ///
        /// If the SSSE3 feature is not enabled for the current target, then
        /// return `None`.
        pub fn new() -> Option<SSSE3VectorBuilder> {
            if is_x86_feature_detected!("ssse3") {
                Some(SSSE3VectorBuilder(()))
            } else {
                None
            }
        }

        /// Create a new u8x16 SSSE3 vector where all of the bytes are set to
        /// the given value.
        #[inline]
        pub fn u8x16_splat(self, n: u8) -> u8x16 {
            // Safe because we know SSSE3 is enabled.
            unsafe { u8x16::splat(n) }
        }

        /// Load 16 bytes from the given slice, with bounds checks.
        #[inline]
        pub fn u8x16_load_unaligned(self, slice: &[u8]) -> u8x16 {
            // Safe because we know SSSE3 is enabled.
            unsafe { u8x16::load_unaligned(slice) }
        }

        /// Load 16 bytes from the given slice, without bounds checks.
        #[inline]
        pub unsafe fn u8x16_load_unchecked_unaligned(self, slice: &[u8]) -> u8x16 {
            // Safe because we know SSSE3 is enabled, but still unsafe
            // because we aren't doing bounds checks.
            u8x16::load_unchecked_unaligned(slice)
        }

        /// Load 16 bytes from the given slice, with bound and alignment checks.
        #[inline]
        pub fn u8x16_load(self, slice: &[u8]) -> u8x16 {
            // Safe because we know SSSE3 is enabled.
            unsafe { u8x16::load(slice) }
        }

        /// Load 16 bytes from the given slice, without bound or alignment checks.
        #[inline]
        pub unsafe fn u8x16_load_unchecked(self, slice: &[u8]) -> u8x16 {
            // Safe because we know SSSE3 is enabled, but still unsafe
            // because we aren't doing bounds checks.
            u8x16::load_unchecked(slice)
        }
    }

    /// A u8x16 is a 128-bit vector with 16 single-byte lanes.
    ///
    /// It provides a safe API that uses only SSE2 or SSSE3 instructions.
    /// The only way for callers to construct a value of this type is
    /// through the SSSE3VectorBuilder type, and the only way to get a
    /// SSSE3VectorBuilder is if the `ssse3` target feature is enabled.
    ///
    /// Note that generally speaking, all uses of this type should get
    /// inlined, otherwise you probably have a performance bug.
    #[derive(Clone, Copy)]
    #[allow(non_camel_case_types)]
    #[repr(transparent)]
    pub struct u8x16 {
        vector: __m128i
    }

    impl u8x16 {
        #[inline]
        unsafe fn splat(n: u8) -> u8x16 {
            u8x16 { vector: _mm_set1_epi8(n as i8) }
        }

        #[inline]
        unsafe fn load_unaligned(slice: &[u8]) -> u8x16 {
            assert!(slice.len() >= 16);
            u8x16::load_unchecked(slice)
        }

        #[inline]
        unsafe fn load_unchecked_unaligned(slice: &[u8]) -> u8x16 {
            let v = _mm_loadu_si128(slice.as_ptr() as *const u8 as *const __m128i);
            u8x16 { vector: v }
        }

        #[inline]
        unsafe fn load(slice: &[u8]) -> u8x16 {
            assert!(slice.len() >= 16);
            assert!(slice.as_ptr() as usize % 16 == 0);
            u8x16::load_unchecked(slice)
        }

        #[inline]
        unsafe fn load_unchecked(slice: &[u8]) -> u8x16 {
            let v = _mm_load_si128(slice.as_ptr() as *const u8 as *const __m128i);
            u8x16 { vector: v }
        }

        #[inline]
        pub fn shuffle(self, indices: u8x16) -> u8x16 {
            // Safe because we know SSSE3 is enabled.
            unsafe {
                u8x16 { vector: _mm_shuffle_epi8(self.vector, indices.vector) }
            }
        }

        #[inline]
        pub fn ne(self, other: u8x16) -> u8x16 {
            // Safe because we know SSSE3 is enabled.
            unsafe {
                let boolv = _mm_cmpeq_epi8(self.vector, other.vector);
                let ones = _mm_set1_epi8(0xFF as u8 as i8);
                u8x16 { vector: _mm_andnot_si128(boolv, ones) }
            }
        }

        #[inline]
        pub fn and(self, other: u8x16) -> u8x16 {
            // Safe because we know SSSE3 is enabled.
            unsafe {
                u8x16 { vector: _mm_and_si128(self.vector, other.vector) }
            }
        }

        #[inline]
        pub fn movemask(self) -> u32 {
            // Safe because we know SSSE3 is enabled.
            unsafe {
                _mm_movemask_epi8(self.vector) as u32
            }
        }

        #[inline]
        pub fn alignr_14(self, other: u8x16) -> u8x16 {
            // Safe because we know SSSE3 is enabled.
            unsafe {
                u8x16 { vector: _mm_alignr_epi8(self.vector, other.vector, 14) }
            }
        }

        #[inline]
        pub fn alignr_15(self, other: u8x16) -> u8x16 {
            // Safe because we know SSSE3 is enabled.
            unsafe {
                u8x16 { vector: _mm_alignr_epi8(self.vector, other.vector, 15) }
            }
        }

        #[inline]
        pub fn bit_shift_right_4(self) -> u8x16 {
            // Safe because we know SSSE3 is enabled.
            unsafe {
                u8x16 { vector: _mm_srli_epi16(self.vector, 4) }
            }
        }

        #[inline]
        pub fn bytes(self) -> [u8; 16] {
            // Safe because __m128i and [u8; 16] are layout compatible
            unsafe { mem::transmute(self) }
        }

        #[inline]
        pub fn replace_bytes(&mut self, value: [u8; 16]) {
            // Safe because __m128i and [u8; 16] are layout compatible
            self.vector = unsafe { mem::transmute(value) };
        }
    }

    impl fmt::Debug for u8x16 {
        fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
            self.bytes().fmt(f)
        }
    }

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