/*
 * Copyright (C) 2014 the FFLAS-FFPACK group
 *
 * Written by   Bastien Vialla<bastien.vialla@lirmm.fr>
 * Brice Boyer (briceboyer) <boyer.brice@gmail.com>
 * Romain Lebreton <romain.lebreton@lirmm.fr>
 *
 *
 * ========LICENCE========
 * This file is part of the library FFLAS-FFPACK.
 *
 * FFLAS-FFPACK is free software: you can redistribute it and/or modify
 * it under the terms of the  GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 * ========LICENCE========
 *.
 */

#ifndef __FFLASFFPACK_fflas_ffpack_utils_simd256_int16_INL
#define __FFLASFFPACK_fflas_ffpack_utils_simd256_int16_INL

#ifndef __FFLASFFPACK_HAVE_AVX2_INSTRUCTIONS
#error "You need AVX2 instructions to perform 256bits operations on int16_t"
#endif

/*
 * Simd256 specialized for int16_t
 */
template <> struct Simd256_impl<true, true, true, 2> : public Simd256i_base {

    /*
     * alias to 256 bit simd register
     */
    using vect_t = __m256i;

    /*
     * alias to 256 bit simd register
     */
    using half_t = __m128i;

    /*
     * define the scalar type corresponding to the specialization
     */
    using scalar_t = int16_t;

    /*
     * Simd128 for scalar_t, to deal half_t
     */
    using simdHalf = Simd128<scalar_t>;

    /*
     *  number of scalar_t in a simd register
     */
    static const constexpr size_t vect_size = 16;

    /*
     *  alignement required by scalar_t pointer to be loaded in a vect_t
     */
    static const constexpr size_t alignment = 32;

    /*
     * Check if the pointer p is a multiple of alignemnt
     */
    template <class T> static constexpr bool valid(T *p) { return (int64_t)p % alignment == 0; }

    /*
     * Check if the number n is a multiple of vect_size
     */
    template <class T> static constexpr bool compliant(T n) { return n % vect_size == 0; }

    /*
     * Converter from vect_t to a tab.
     * exple:
     *	Converter conv;
     *	conv.v = a;
     *	scalart_t x = conv.t[1]
     */
    union Converter {
        vect_t v;
        scalar_t t[vect_size];
    };

    /*
     *  Broadcast 16-bit integer a to all elements of dst. This intrinsic may generate the vpbroadcastw.
     *  Return [x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x] int16_t
     */
    static INLINE CONST vect_t set1(const scalar_t x) { return _mm256_set1_epi16(x); }

    /*
     *  Set packed 16-bit integers in dst with the supplied values.
     *  Return [x0,x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15] int16_t
     */
    static INLINE CONST vect_t set(const scalar_t x0, const scalar_t x1, const scalar_t x2, const scalar_t x3,
                                   const scalar_t x4, const scalar_t x5, const scalar_t x6, const scalar_t x7,
                                   const scalar_t x8, const scalar_t x9, const scalar_t x10, const scalar_t x11,
                                   const scalar_t x12, const scalar_t x13, const scalar_t x14, const scalar_t x15) {
        return _mm256_set_epi16(x15, x14, x13, x12, x11, x10, x9, x8, x7, x6, x5, x4, x3, x2, x1, x0);
    }

    /*
     *  Gather 16-bit integer elements with indexes idx[0], ..., idx[15] from the address p in vect_t.
     *  Return [p[idx[0]], p[idx[1]], p[idx[2]], p[idx[3]],
     p[idx[4]], p[idx[5]], p[idx[6]], p[idx[7]],
     p[idx[8]], p[idx[9]], p[idx[10]], p[idx[11]],
     p[idx[12]], p[idx[13]], p[idx[14]], p[idx[15]]] int16_t
     */
    template <class T> static INLINE PURE vect_t gather(const scalar_t *const p, const T *const idx) {
        return set(p[idx[0]], p[idx[1]], p[idx[2]], p[idx[3]], p[idx[4]], p[idx[5]], p[idx[6]], p[idx[7]], p[idx[8]],
                   p[idx[9]], p[idx[10]], p[idx[11]], p[idx[12]], p[idx[13]], p[idx[14]], p[idx[15]]);
    }

    /*
     * Load 256-bits of integer data from memory into dst.
     * p must be aligned on a 32-byte boundary or a general-protection exception will be generated.
     * Return [p[0],p[1],p[2],p[3],p[4],p[5],p[6],p[7],p[8],p[9],p[10],p[11]p[12],p[13],p[14],p[15]] int16_t
     */
    static INLINE PURE vect_t load(const scalar_t *const p) {
        return _mm256_load_si256(reinterpret_cast<const vect_t *>(p));
    }

    /*
     * Load 256-bits of integer data from memory into dst.
     * p does not need to be aligned on any particular boundary.
     * Return [p[0],p[1],p[2],p[3],p[4],p[5],p[6],p[7],p[8],p[9],p[10],p[11]p[12],p[13],p[14],p[15]] int16_t
     */
    static INLINE PURE vect_t loadu(const scalar_t *const p) {
        return _mm256_loadu_si256(reinterpret_cast<const vect_t *>(p));
    }

    /*
     * Store 256-bits of integer data from a into memory.
     * p must be aligned on a 32-byte boundary or a general-protection exception will be generated.
     */
    static INLINE void store(scalar_t *p, vect_t v) {
        _mm256_store_si256(reinterpret_cast<vect_t *>(p), v);
    }

    /*
     * Store 256-bits of integer data from a into memory.
     * p does not need to be aligned on any particular boundary.
     */
    static INLINE void storeu(scalar_t *p, vect_t v) {
        _mm256_storeu_si256(reinterpret_cast<vect_t *>(p), v);
    }

    /*
     * Store 256-bits of integer data from a into memory using a non-temporal memory hint.
     * p must be aligned on a 32-byte boundary or a general-protection exception may be generated.
     */
    static INLINE void stream(scalar_t *p, const vect_t v) {
        _mm256_stream_si256(reinterpret_cast<vect_t *>(p), v);
    }

    /*
     * Shift packed 16-bit integers in a left by s while shifting in zeros, and store the results in vect_t.
     * Args   : [a0, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15] int16_t
     * Return : [a0 << s, a1 << s, a2 << s, a3 << s, a4 << s, a5 << s, a6 << s, a7 << s,
     *	   a8 << s, a9 << s, a10 << s, a11 << s, a12 << s, a13 << s, a14 << s, a15 << s] int16_t
     */
    template<int s>
    static INLINE CONST vect_t sll(const vect_t a) { return _mm256_slli_epi16(a, s); }

    /*
     * Shift packed 16-bit integers in a right by s while shifting in zeros, and store the results in vect_t.
     * Args   : [a0, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15] int16_t
     * Return : [a0 >> s, a1 >> s, a2 >> s, a3 >> s, a4 >> s, a5 >> s, a6 >> s, a7 >> s,
     *	   a8 >> s, a9 >> s, a10 >> s, a11 >> s, a12 >> s, a13 >> s, a14 >> s, a15 >> s] int16_t
     */
    template<int s>
    static INLINE CONST vect_t srl(const vect_t a) { return _mm256_srli_epi16(a, s); }

    /*
     * Shift packed 16-bit integers in a right by s while shifting in sign bits, and store the results in vect_t.
     * Args   :	[a0, ..., a15]		int16_t
     * Return : 	[a0 >> s, ..., a15 >> s] int16_t
     */
    template<int s>
    static INLINE CONST vect_t sra(const vect_t a) { return _mm256_srai_epi16(a, s); }

    /*
     * Shuffle 16-bit integers in a using the control in imm8, and store the results in dst.
     * Args   : [a0, ..., a15] int16_t
     * Return : [a[s[0..3]], ..., a[s[60..63]] int16_t
     */
    template<uint64_t s>
    static INLINE CONST vect_t shuffle(const vect_t a) {
        //#pragma warning "The simd shuffle function is emulated, it may impact the performances.";
        Converter conv;
        conv.v = a;
        return set (conv.t[( s      & 0x000000000000000F)], conv.t[( s      & 0x00000000000000F0)],
                    conv.t[((s>> 8) & 0x000000000000000F)], conv.t[((s>> 8) & 0x00000000000000F0)],
                    conv.t[((s>>16) & 0x000000000000000F)], conv.t[((s>>16) & 0x00000000000000F0)],
                    conv.t[((s>>24) & 0x000000000000000F)], conv.t[((s>>24) & 0x00000000000000F0)],
                    conv.t[((s>>32) & 0x000000000000000F)], conv.t[((s>>32) & 0x00000000000000F0)],
                    conv.t[((s>>40) & 0x000000000000000F)], conv.t[((s>>40) & 0x00000000000000F0)],
                    conv.t[((s>>48) & 0x000000000000000F)], conv.t[((s>>48) & 0x00000000000000F0)],
                    conv.t[((s>>56) & 0x000000000000000F)], conv.t[((s>>56) & 0x00000000000000F0)]);
    }

    /*
     * Unpack and interleave 16-bit integers from the low half of a and b within 128-bit lanes, and store the results in dst.
     * Args   :	[a0, ..., a15] int16_t
     [b0, ..., b15] int16_t
     * Return :	[a0, b0, a1, b1, ..., a8, b8, a9, b9, ...] int16_t
     */
    static INLINE CONST vect_t unpacklo_twice(const vect_t a, const vect_t b) { return _mm256_unpacklo_epi16(a, b); }

    /*
     * Unpack and interleave 16-bit integers from the high half of a and b within 128-bit lanes, and store the results in dst.
     * Args   :	[a0, ..., a15] int16_t
     [b0, ..., b15] int16_t
     * Return :	[a4, b4, a5, b5, ..., a12, b12, a13, b13, ...] int16_t
     */
    static INLINE CONST vect_t unpackhi_twice(const vect_t a, const vect_t b) { return _mm256_unpackhi_epi16(a, b); }

    /*
     * Unpack and interleave 16-bit integers from the low half of a and b, and store the results in dst.
     * Args   :	[a0, ..., a15] int16_t
     [b0, ..., b15] int16_t
     * Return :	[a0, b0, ..., a7, b7] int16_t
     */
    static INLINE CONST vect_t unpacklo(const vect_t a, const vect_t b) {
        // using Simd256_64 = Simd256<uint64_t>;
        // vect_t a1 = Simd256_64::template shuffle<0xD8>(a); // 0xD8 = 3120 base_4 so a -> [a0,a2,a1,a3] uint64
        // vect_t b1 = Simd256_64::template shuffle<0xD8>(b); // 0xD8 = 3120 base_4
        // return unpacklo_twice(a1, b1);
        vect_t a1 = _mm256_permute4x64_epi64(a, 0xD8);
        vect_t b1 = _mm256_permute4x64_epi64(a, 0xD8);
        return unpacklo_twice(a1, b1);

    }

    /*
     * Unpack and interleave 16-bit integers from the high half of a and b, and store the results in dst.
     * Args   :	[a0, ..., a15] int16_t
     [b0, ..., b15] int16_t
     * Return :	[a8, b8, ..., a15, b15] int16_t
     */
    static INLINE CONST vect_t unpackhi(const vect_t a, const vect_t b) {
        // using Simd256_64 = Simd256<uint64_t>;
        // vect_t a1 = Simd256_64::template shuffle<0xD8>(a); // 0xD8 = 3120 base_4
        // vect_t b1 = Simd256_64::template shuffle<0xD8>(b); // 0xD8 = 3120 base_4
        // return unpackhi_twice(a1, b1);
        vect_t a1 = _mm256_permute4x64_epi64(a, 0xD8);
        vect_t b1 = _mm256_permute4x64_epi64(a, 0xD8);
        return unpackhi_twice(a1, b1);

    }

    /*
     * Unpack and interleave 16-bit integers from the low then high half of a and b, and store the results in dst.
     * Args   :	[a0, ..., a15] int16_t
     [b0, ..., b15] int16_t
     * Return :	[a0, b0, ..., a7, b7] int16_t
     *			[a8, b8, ..., a15, b15] int16_t
     */
    static INLINE void unpacklohi(vect_t& s1, vect_t& s2, const vect_t a, const vect_t b) {
        // using Simd256_64 = Simd256<uint64_t>;
        // vect_t a1 = Simd256_64::template shuffle<0xD8>(a); // 0xD8 = 3120 base_4
        // vect_t b1 = Simd256_64::template shuffle<0xD8>(b); // 0xD8 = 3120 base_4
        vect_t a1 = _mm256_permute4x64_epi64(a, 0xD8);
        vect_t b1 = _mm256_permute4x64_epi64(a, 0xD8);
        s1 = unpacklo_twice(a1, b1);
        s2 = unpackhi_twice(a1, b1);

    }

    /*
     * Blend packed 16-bit integers from a and b in each 128 lane using control mask imm8, and store the results in dst.
     * Args   :	[a0, ..., a15] int16_t
     [b0, ..., b15] int16_t
     * Return :	[s[0]?a0:b0,   , s[15]?a15:b15] int16_t
     */
    template<uint8_t s>
    static INLINE CONST vect_t blend_twice(const vect_t a, const vect_t b) {
        return _mm256_blend_epi16(a, b, s);
    }

    /*
     * Add packed 16-bits integer in a and b, and store the results in vect_t.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     * Return :	 [a0+b0, a1+b1, a2+b2, a3+b3, a4+b4, a5+b5, a6+b6, a7+b7,
     a8+b8, a9+b9, a10+b10, a11+b11, a12+b12, a13+b13, a14+b14, a15+b15]   int16_t
     */
    static INLINE CONST vect_t add(const vect_t a, const vect_t b) { return _mm256_add_epi16(a, b); }

    static INLINE vect_t addin(vect_t &a, const vect_t b) { return a = add(a, b); }

    /*
     * Subtract packed 16-bit integers in b from packed 16-bit integers in a, and store the results in vect_t.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     * Return : 	[a0-b0, a1-b1, a2-b2, a3-b3, a4-b4, a5-b5, a6-b6, a7-b7,
     a8-b8, a9-b9, a10-b10, a11-b11, a12-b12, a13-b13, a14-b14, a15-b15]  int16_t
     */
    static INLINE CONST vect_t sub(const vect_t a, const vect_t b) { return _mm256_sub_epi16(a, b); }

    static INLINE vect_t subin(vect_t &a, const vect_t b) { return a = sub(a, b); }

    /*
     * Multiply the packed 16-bit integers in a and b, producing intermediate 32-bit integers, and store the low 16 bits
     of the intermediate integers in vect_t.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     * Return : [a0*b0 smod 2^16, ..., a15*b15 smod 2^16]	int16_t
     *	   where (a smod p) is the signed representant of a modulo p, that is -p/2 <= (a smod p) < p/2
     */
    static INLINE CONST vect_t mullo(const vect_t a, const vect_t b) { return _mm256_mullo_epi16(a, b); }

    static INLINE CONST vect_t mul(const vect_t a, const vect_t b) { return mullo(a, b); }

    /*
     * Multiply the packed 16-bit integers in a and b, producing intermediate 32-bit integers, and store the high 16
     bits of the intermediate integers in vect_t.
     * Args   : [a0, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15] int16_t
     *	   [b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12, b13, b14, b15] int16_t
     * Return : [Floor(a0*b0/2^16), ..., Floor(a15*b15/2^16)] int16_t
     */
    static INLINE CONST vect_t mulhi(const vect_t a, const vect_t b) { return _mm256_mulhi_epi16(a, b); }

    /*
     * Multiply the low 8-bit integers from each packed 16-bit element in a and b, and store the signed 16-bit results
     in dst.
     * Args   : [a0, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15] int16_t
     *	   [b0, b1, b2, b3, b4, b5, b6, b7, b8, b9, b10, b11, b12, b13, b14, b15] int16_t
     * Return : [(a0 smod 2^8)*(b0 smod 2^8), ..., (a15 smod 2^8)*(b15 smod 2^8)]	int16_t
     *	   where (a smod p) is the signed representant of a modulo p, that is -p/2 <= (a smod p) < p/2
     */
    static INLINE CONST vect_t mulx(vect_t a, vect_t b) {
        //#pragma warning "The simd mulx function is emulated, it may impact the performances."
        vect_t a1, b1, mask1, mask2;
        mask1 = set1(0x00FF);
        mask2 = set1(0x0080);
        a1 = add(a,mask2);
        a1 = vand(a1,mask1);
        a1 = sub(a1,mask2);
        b1 = add(b,mask2);
        b1 = vand(b1,mask1);
        b1 = sub(b1,mask2);
        return mul(a1,b1);
    }

    /*
     * Multiply the packed 16-bit integers in a and b, producing intermediate 32-bit integers,
     * keep the low 16 bits of the intermediate and add the low 16-bits of c.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     [c0, ..., c15]		int16_t
     * Return :	[(a0*b0+c0) smod 2^16, ..., (a15*b15+c15) smod 2^16]	int16_t
     */
    static INLINE CONST vect_t fmadd(const vect_t c, const vect_t a, const vect_t b) { return add(c, mul(a, b)); }

    static INLINE vect_t fmaddin(vect_t &c, const vect_t a, const vect_t b) { return c = fmadd(c, a, b); }

    /*
     * Multiply the low 8-bit integers from each packed 16-bit element in a and b,
     * keep the signed 16-bit results and add the low 16-bits of c.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     [c0, ..., c15]		int16_t
     * Return :	[((a0 smod 2^8)*(b0 smod 2^8)+c0) smod 2^16, ...,
     *		 ((a15 smod 2^8)*(b15 smod 2^8)+c15) smod 2^16]	int16_t
     */
    static INLINE CONST vect_t fmaddx(const vect_t c, const vect_t a, const vect_t b) { return add(c, mulx(a, b)); }

    static INLINE vect_t fmaddxin(vect_t &c, const vect_t a, const vect_t b) { return c = fmaddx(c, a, b); }

    /*
     * Multiply the packed 16-bit integers in a and b, producing intermediate 32-bit integers,
     * and substract the low 16 bits of the intermediate from elements of c.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     [c0, ..., c15]		int16_t
     * Return :	[(-a0*b0+c0) smod 2^16, ..., (-a15*b15+c15) smod 2^16]	int16_t
     */
    static INLINE CONST vect_t fnmadd(const vect_t c, const vect_t a, const vect_t b) { return sub(c, mul(a, b)); }

    static INLINE vect_t fnmaddin(vect_t &c, const vect_t a, const vect_t b) { return c = fnmadd(c, a, b); }

    /*
     * Multiply the low 8-bit integers from each packed 16-bit element in a and b,
     * keep the signed 16-bit results and substract them from elements of c.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     [c0, ..., c15]		int16_t
     * Return :	[(-(a0 smod 2^8)*(b0 smod 2^8)+c0) smod 2^16, ...,
     *		 (-(a15 smod 2^8)*(b15 smod 2^8)+c15) smod 2^16]		int16_t
     */
    static INLINE CONST vect_t fnmaddx(const vect_t c, const vect_t a, const vect_t b) { return sub(c, mulx(a, b)); }

    static INLINE vect_t fnmaddxin(vect_t &c, const vect_t a, const vect_t b) { return c = fnmaddx(c, a, b); }

    /*
     * Multiply packed 16-bit integers in a and b, producing intermediate 32-bit integers,
     * and substract elements of c to the low 16-bits of the intermediate.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     [c0, ..., c15]		int16_t
     * Return :	[(a0*b0-c0) smod 2^16, ..., (a15*b15-c15) smod 2^16]	int16_t
     */
    static INLINE CONST vect_t fmsub(const vect_t c, const vect_t a, const vect_t b) { return sub(mul(a, b), c); }

    static INLINE vect_t fmsubin(vect_t &c, const vect_t a, const vect_t b) { return c = fmsub(c, a, b); }

    /*
     * Multiply the low 8-bit integers from each packed 16-bit element in a and b,
     * keep the signed 16-bit results and substract elements of c from them.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     [c0, ..., c15]		int16_t
     * Return :	[((a0 smod 2^8)*(b0 smod 2^8)-c0) smod 2^16, ...,
     *		 ((a15 smod 2^8)*(b15 smod 2^8)-c15) smod 2^16]		int16_t
     */
    static INLINE CONST vect_t fmsubx(const vect_t c, const vect_t a, const vect_t b) { return sub(mulx(a, b), c); }

    static INLINE vect_t fmsubxin(vect_t &c, const vect_t a, const vect_t b) { return c = fmsubx(c, a, b); }

    /*
     * Compare packed 16-bits in a and b for equality, and store the results in vect_t.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     * Return : [(a0==b0) ? 0xFFFF : 0, (a1==b1) ? 0xFFFF : 0,
     (a2==b2) ? 0xFFFF : 0, (a3==b3) ? 0xFFFF : 0,
     (a4==b4) ? 0xFFFF : 0, (a5==b5) ? 0xFFFF : 0,
     (a6==b6) ? 0xFFFF : 0, (a7==b7) ? 0xFFFF : 0,
     (a8==b8) ? 0xFFFF : 0, (a9==b9) ? 0xFFFF : 0,
     (a10==b10) ? 0xFFFF : 0, (a11==b11) ? 0xFFFF : 0,
     (a12==b12) ? 0xFFFF : 0, (a13==b13) ? 0xFFFF : 0,
     (a14==b14) ? 0xFFFF : 0, (a15==b15) ? 0xFFFF : 0]		     int16_t
     */
    static INLINE CONST vect_t eq(const vect_t a, const vect_t b) { return _mm256_cmpeq_epi16(a, b); }

    /*
     * Compare packed 16-bits in a and b for greater-than, and store the results in vect_t.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     * Return : [(a0>b0) ? 0xFFFF : 0, (a1>b1) ? 0xFFFF : 0,
     (a2>b2) ? 0xFFFF : 0, (a3>b3) ? 0xFFFF : 0,
     (a4>b4) ? 0xFFFF : 0, (a5>b5) ? 0xFFFF : 0,
     (a6>b6) ? 0xFFFF : 0, (a7>b7) ? 0xFFFF : 0,
     (a8>b8) ? 0xFFFF : 0, (a9>b9) ? 0xFFFF : 0,
     (a10>b10) ? 0xFFFF : 0, (a11>b11) ? 0xFFFF : 0,
     (a12>b12) ? 0xFFFF : 0, (a13>b13) ? 0xFFFF : 0,
     (a14>b14) ? 0xFFFF : 0, (a15>b15) ? 0xFFFF : 0]					  int16_t
     */
    static INLINE CONST vect_t greater(const vect_t a, const vect_t b) { return _mm256_cmpgt_epi16(a, b); }

    /*
     * Compare packed 16-bits in a and b for lesser-than, and store the results in vect_t.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     * Return : [(a0<b0) ? 0xFFFF : 0, (a1<b1) ? 0xFFFF : 0,
     (a2<b2) ? 0xFFFF : 0, (a3<b3) ? 0xFFFF : 0,
     (a4<b4) ? 0xFFFF : 0, (a5<b5) ? 0xFFFF : 0,
     (a6<b6) ? 0xFFFF : 0, (a7<b7) ? 0xFFFF : 0,
     (a8<b8) ? 0xFFFF : 0, (a9<b9) ? 0xFFFF : 0,
     (a10<b10) ? 0xFFFF : 0, (a11<b11) ? 0xFFFF : 0,
     (a12<b12) ? 0xFFFF : 0, (a13<b13) ? 0xFFFF : 0,
     (a14<b14) ? 0xFFFF : 0, (a15>b15) ? 0xFFFF : 0] 					  int16_t
     */
    static INLINE CONST vect_t lesser(const vect_t a, const vect_t b) { return _mm256_cmpgt_epi16(b, a); }

    /*
     * Compare packed 16-bits in a and b for greater or equal than, and store the results in vect_t.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     * Return : [(a0>=b0) ? 0xFFFF : 0, (a1>=b1) ? 0xFFFF : 0,
     (a2>=b2) ? 0xFFFF : 0, (a3>=b3) ? 0xFFFF : 0,
     (a4>=b4) ? 0xFFFF : 0, (a5>=b5) ? 0xFFFF : 0,
     (a6>=b6) ? 0xFFFF : 0, (a7>=b7) ? 0xFFFF : 0,
     (a8>=b8) ? 0xFFFF : 0, (a9>=b9) ? 0xFFFF : 0,
     (a10>=b10) ? 0xFFFF : 0, (a11>=b11) ? 0xFFFF : 0,
     (a12>=b12) ? 0xFFFF : 0, (a13>=b13) ? 0xFFFF : 0,
     (a14>=b14) ? 0xFFFF : 0, (a15>=b15) ? 0xFFFF : 0]					  int16_t
     */
    static INLINE CONST vect_t greater_eq(const vect_t a, const vect_t b) { return vor(greater(a, b), eq(a, b)); }

    /*
     * Compare packed 16-bits in a and b for lesser or equal than, and store the results in vect_t.
     * Args   :	[a0, ..., a15]		int16_t
     [b0, ..., b15]		int16_t
     * Return : [(a0<=b0) ? 0xFFFF : 0, (a1<=b1) ? 0xFFFF : 0,
     (a2<=b2) ? 0xFFFF : 0, (a3<=b3) ? 0xFFFF : 0,
     (a4<=b4) ? 0xFFFF : 0, (a5<=b5) ? 0xFFFF : 0,
     (a6<=b6) ? 0xFFFF : 0, (a7<=b7) ? 0xFFFF : 0,
     (a8<=b8) ? 0xFFFF : 0, (a9<=b9) ? 0xFFFF : 0,
     (a10<=b10) ? 0xFFFF : 0, (a11<=b11) ? 0xFFFF : 0,
     (a12<=b12) ? 0xFFFF : 0, (a13<=b13) ? 0xFFFF : 0,
     (a14<=b14) ? 0xFFFF : 0, (a15<=b15) ? 0xFFFF : 0] 					   int16_t
     */
    static INLINE CONST vect_t lesser_eq(const vect_t a, const vect_t b) { return vor(lesser(a, b), eq(a, b)); }

    /*
     * Horizontally add 16-bits elements of a.
     * Args   : [a0, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15]
     * Return : a0+a1+a2+a3+a4+a5+a6+a7+a8+a9+a10+a11+a12+a13+a14+a15
     */
    static INLINE CONST scalar_t hadd_to_scal(const vect_t a) {
        Converter ca;
        ca.v = a;
        return scalar_t(ca.t[0] + ca.t[1] + ca.t[2] + ca.t[3] + ca.t[4] + ca.t[5] + ca.t[6] + ca.t[7] + ca.t[8] + ca.t[9] +
                        ca.t[10] + ca.t[11] + ca.t[12] + ca.t[13] + ca.t[14] + ca.t[15]);
    }

    static INLINE CONST vect_t round(const vect_t a) { return a; }

    static INLINE vect_t mod(vect_t &C, const vect_t &P, const vect_t &INVP, const vect_t &NEGP, const vect_t &MIN,
                             const vect_t &MAX, vect_t &Q, vect_t &T) {
#ifdef __INTEL_COMPILER
        C = _mm256_rem_epi16(C, P);
#else
        FFLASFFPACK_abort("pas implementé");
#endif
        NORML_MOD(C, P, NEGP, MIN, MAX, Q, T);
        return C;
    }
};

/*
 * Simd128 specialized for uint16_t
 */
template <> struct Simd256_impl<true, true, false, 2> : public Simd256_impl<true, true, true, 2> {

    /*
     * define the scalar type corresponding to the specialization
     */
    using scalar_t = uint16_t;

    /*
     * Simd128 for scalar_t, to deal half_t
     */
    using simdHalf = Simd128<scalar_t>;

    /*
     * Converter from vect_t to a tab.
     * exple:
     *	Converter conv;
     *	conv.v = a;
     *	scalart_t x = conv.t[1]
     */
    union Converter {
        vect_t v;
        scalar_t t[vect_size];
    };

    /*
     *  Broadcast 16-bit unsigned integer a to all elements of dst. This intrinsic may generate the vpbroadcastw.
     *  Return [x,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x] uint16_t
     */
    static INLINE CONST vect_t set1(const scalar_t x) { return _mm256_set1_epi16(x); }

    /*
     *  Set packed 16-bit unsigned integers in dst with the supplied values.
     *  Return [x0,x1,x2,x3,x4,x5,x6,x7,x8,x9,x10,x11,x12,x13,x14,x15] uint16_t
     */
    static INLINE CONST vect_t set(const scalar_t x0, const scalar_t x1, const scalar_t x2, const scalar_t x3,
                                   const scalar_t x4, const scalar_t x5, const scalar_t x6, const scalar_t x7,
                                   const scalar_t x8, const scalar_t x9, const scalar_t x10, const scalar_t x11,
                                   const scalar_t x12, const scalar_t x13, const scalar_t x14, const scalar_t x15) {
        return _mm256_set_epi16(x15, x14, x13, x12, x11, x10, x9, x8, x7, x6, x5, x4, x3, x2, x1, x0);
    }

    /*
     *  Gather 16-bit integer elements with indexes idx[0], ..., idx[15] from the address p in vect_t.
     *  Return [p[idx[0]], p[idx[1]], p[idx[2]], p[idx[3]],
     p[idx[4]], p[idx[5]], p[idx[6]], p[idx[7]],
     p[idx[8]], p[idx[9]], p[idx[10]], p[idx[11]],
     p[idx[12]], p[idx[13]], p[idx[14]], p[idx[15]]] uint16_t
     */
    template <class T> static INLINE PURE vect_t gather(const scalar_t *const p, const T *const idx) {
        return set(p[idx[0]], p[idx[1]], p[idx[2]], p[idx[3]], p[idx[4]], p[idx[5]], p[idx[6]], p[idx[7]], p[idx[8]],
                   p[idx[9]], p[idx[10]], p[idx[11]], p[idx[12]], p[idx[13]], p[idx[14]], p[idx[15]]);
    }

    /*
     * Load 256-bits of unsigned integer data from memory into dst.
     * p must be aligned on a 32-byte boundary or a general-protection exception will be generated.
     * Return [p[0],p[1],p[2],p[3],p[4],p[5],p[6],p[7],p[8],p[9],p[10],p[11]p[12],p[13],p[14],p[15]] uint16_t
     */
    static INLINE PURE vect_t load(const scalar_t *const p) {
        return _mm256_load_si256(reinterpret_cast<const vect_t *>(p));
    }

    /*
     * Load 256-bits of unsigned integer data from memory into dst.
     * p does not need to be aligned on any particular boundary.
     * Return [p[0],p[1],p[2],p[3],p[4],p[5],p[6],p[7],p[8],p[9],p[10],p[11]p[12],p[13],p[14],p[15]] uint16_t
     */
    static INLINE PURE vect_t loadu(const scalar_t *const p) {
        return _mm256_loadu_si256(reinterpret_cast<const vect_t *>(p));
    }

    /*
     * Store 256-bits of unsigned integer data from a into memory.
     * p must be aligned on a 32-byte boundary or a general-protection exception will be generated.
     */
    static INLINE void store(scalar_t *p, vect_t v) {
        _mm256_store_si256(reinterpret_cast<vect_t *>(p), v);
    }

    /*
     * Store 256-bits of unsigned integer data from a into memory.
     * p does not need to be aligned on any particular boundary.
     */
    static INLINE void storeu(scalar_t *p, vect_t v) {
        _mm256_storeu_si256(reinterpret_cast<vect_t *>(p), v);
    }

    /*
     * Store 256-bits of unsigned integer data from a into memory using a non-temporal memory hint.
     * p must be aligned on a 32-byte boundary or a general-protection exception may be generated.
     */
    static INLINE void stream(scalar_t *p, const vect_t v) {
        _mm256_stream_si256(reinterpret_cast<vect_t *>(p), v);
    }

    /*
     * Shift packed 16-bit unsigned integers in a right by s while shifting in sign bits, and store the results in vect_t.
     * Args   : [a0, ..., a15]				int16_t
     * Return : [Floor(a0/2^s), ..., Floor(a15/2^s)]	int16_t
     */
    template<int s>
    static INLINE CONST vect_t sra(const vect_t a) { return _mm256_srli_epi16(a, s); }

    static INLINE CONST vect_t greater(vect_t a, vect_t b) {
        vect_t x;
        x = set1((static_cast<scalar_t>(1) << (sizeof(scalar_t) * 8 - 1)));
        a = sub(a,x);
        b = sub(b,x);
        return _mm256_cmpgt_epi16(a, b);
    }

    static INLINE CONST vect_t lesser(vect_t a, vect_t b) {
        vect_t x;
        x = set1((static_cast<scalar_t>(1) << (sizeof(scalar_t) * 8 - 1)));
        a = sub(a,x);
        b = sub(b,x);
        return _mm256_cmpgt_epi16(b, a);
    }

    static INLINE CONST vect_t greater_eq(const vect_t a, const vect_t b) { return vor(greater(a, b), eq(a, b)); }

    static INLINE CONST vect_t lesser_eq(const vect_t a, const vect_t b) { return vor(lesser(a, b), eq(a, b)); }

    /*
     * Multiply the packed unsigned 16-bit integers in a and b, producing intermediate 32-bit integers,
     * and store the high 16 bits of the intermediate integers in vect_t.
     * Args   :	[a0, ..., a15]		uint16_t
     [b0, ..., b15]		uint16_t
     * Return : [Floor(a0*b0/2^16), ..., Floor(a15*b15/2^16)] uint16_t
     */
    static INLINE CONST vect_t mulhi(const vect_t a, const vect_t b) { return _mm256_mulhi_epu16(a, b); }

    /*
     * Multiply the low unsigned 8-bit integers from each packed 16-bit element in a and b,
     * and store the signed 16-bit results in vect_t.
     * Args   :	[a0, ..., a15]		uint16_t
     [b0, ..., b15]		uint16_t
     * Return : [(a0 mod 2^8)*(b0 mod 2^8), ..., (a15 mod 2^8)*(b15 mod 2^8)] uint16_t
     */
    static INLINE CONST vect_t mulx(vect_t a, vect_t b) {
        //#pragma warning "The simd mulx function is emulated, it may impact the performances."
        vect_t a1, b1, mask1;
        mask1 = set1(0x00FF);
        a1 = vand(a,mask1);
        b1 = vand(b,mask1);
        return mul(a1,b1);
    }

    static INLINE CONST vect_t fmaddx(const vect_t c, const vect_t a, const vect_t b) { return add(c, mulx(a, b)); }

    static INLINE vect_t fmaddxin(vect_t &c, const vect_t a, const vect_t b) { return c = fmaddx(c, a, b); }

    static INLINE CONST vect_t fnmaddx(const vect_t c, const vect_t a, const vect_t b) { return sub(c, mulx(a, b)); }

    static INLINE vect_t fnmaddxin(vect_t &c, const vect_t a, const vect_t b) { return c = fnmaddx(c, a, b); }

    static INLINE CONST vect_t fmsubx(const vect_t c, const vect_t a, const vect_t b) { return sub(mulx(a, b), c); }

    static INLINE vect_t fmsubxin(vect_t &c, const vect_t a, const vect_t b) { return c = fmsubx(c, a, b); }

    /*
     * Horizontally add 16-bits elements of a.
     * Args   : [a0, a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14, a15]
     * Return : a0+a1+a2+a3+a4+a5+a6+a7+a8+a9+a10+a11+a12+a13+a14+a15
     */
    static INLINE CONST scalar_t hadd_to_scal(const vect_t a) {
        Converter ca;
        ca.v = a;
        return scalar_t(ca.t[0] + ca.t[1] + ca.t[2] + ca.t[3] + ca.t[4] + ca.t[5] + ca.t[6] + ca.t[7] + ca.t[8] + ca.t[9] +
                        ca.t[10] + ca.t[11] + ca.t[12] + ca.t[13] + ca.t[14] + ca.t[15]);
    }
};  //Simd256_impl<true,true,false,2>

#endif // __FFLASFFPACK_fflas_ffpack_utils_simd256_int16_INL
/* -*- mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
// vim:sts=4:sw=4:ts=4:et:sr:cino=>s,f0,{0,g0,(0,\:0,t0,+0,=s
