/*

 * Bitshuffle - Filter for improving compression of typed binary data.

 *

 * Author: Kiyoshi Masui <kiyo@physics.ubc.ca>

 * Website: http://www.github.com/kiyo-masui/bitshuffle

 * Created: 2014

 *

 * Note: Adapted for c-blosc by Francesc Alted.

 *

 * See LICENSES/BITSHUFFLE.txt file for details about copyright and

 * rights to use.

 *

 */

#include "bitshuffle-generic.h"

#include "bitshuffle-sse2.h"

/* Define dummy functions if SSE2 is not available for the compilation target and compiler. */

#if !defined(__SSE2__)

#include <stdlib.h>

int64_t blosc_internal_bshuf_trans_byte_elem_sse2(void* in, void* out, const size_t size,

                                                  const size_t elem_size, void* tmp_buf) {

    abort();

}

int64_t blosc_internal_bshuf_untrans_bit_elem_sse2(void* in, void* out, const size_t size,

                                           const size_t elem_size, void* tmp_buf) {

    abort();

}

#else /* defined(__SSE2__) */

#include <emmintrin.h>

/* The next is useful for debugging purposes */

#if 0

#include <stdio.h>

#include <string.h>

static void printxmm(__m128i xmm0)

{

  uint8_t buf[32];

  ((__m128i *)buf)[0] = xmm0;

  printf("%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x,%x\n",

          buf[0], buf[1], buf[2], buf[3],

          buf[4], buf[5], buf[6], buf[7],

          buf[8], buf[9], buf[10], buf[11],

          buf[12], buf[13], buf[14], buf[15]);

}

#endif

/* ---- Worker code that requires SSE2. Intel Petium 4 (2000) and later. ---- */

/* Transpose bytes within elements for 16 bit elements. */

static int64_t bshuf_trans_byte_elem_SSE_16(void* in, void* out, const size_t size) {

    char* in_b = (char*) in;

    char* out_b = (char*) out;

    __m128i a0, b0, a1, b1;

    size_t ii;

    for (ii=0; ii + 15 < size; ii += 16) {

        a0 = _mm_loadu_si128((__m128i *) &in_b[2*ii + 0*16]);

        b0 = _mm_loadu_si128((__m128i *) &in_b[2*ii + 1*16]);

        a1 = _mm_unpacklo_epi8(a0, b0);

        b1 = _mm_unpackhi_epi8(a0, b0);

        a0 = _mm_unpacklo_epi8(a1, b1);

        b0 = _mm_unpackhi_epi8(a1, b1);

        a1 = _mm_unpacklo_epi8(a0, b0);

        b1 = _mm_unpackhi_epi8(a0, b0);

        a0 = _mm_unpacklo_epi8(a1, b1);

        b0 = _mm_unpackhi_epi8(a1, b1);

        _mm_storeu_si128((__m128i *) &out_b[0*size + ii], a0);

        _mm_storeu_si128((__m128i *) &out_b[1*size + ii], b0);

    }

    return blosc_internal_bshuf_trans_byte_elem_remainder(in, out, size, 2,

            size - size % 16);

}

/* Transpose bytes within elements for 32 bit elements. */

static int64_t bshuf_trans_byte_elem_SSE_32(void* in, void* out, const size_t size) {

    char* in_b = (char*) in;

    char* out_b = (char*) out;

    __m128i a0, b0, c0, d0, a1, b1, c1, d1;

    size_t ii;

    for (ii=0; ii + 15 < size; ii += 16) {

        a0 = _mm_loadu_si128((__m128i *) &in_b[4*ii + 0*16]);

        b0 = _mm_loadu_si128((__m128i *) &in_b[4*ii + 1*16]);

        c0 = _mm_loadu_si128((__m128i *) &in_b[4*ii + 2*16]);

        d0 = _mm_loadu_si128((__m128i *) &in_b[4*ii + 3*16]);

        a1 = _mm_unpacklo_epi8(a0, b0);

        b1 = _mm_unpackhi_epi8(a0, b0);

        c1 = _mm_unpacklo_epi8(c0, d0);

        d1 = _mm_unpackhi_epi8(c0, d0);

        a0 = _mm_unpacklo_epi8(a1, b1);

        b0 = _mm_unpackhi_epi8(a1, b1);

        c0 = _mm_unpacklo_epi8(c1, d1);

        d0 = _mm_unpackhi_epi8(c1, d1);

        a1 = _mm_unpacklo_epi8(a0, b0);

        b1 = _mm_unpackhi_epi8(a0, b0);

        c1 = _mm_unpacklo_epi8(c0, d0);

        d1 = _mm_unpackhi_epi8(c0, d0);

        a0 = _mm_unpacklo_epi64(a1, c1);

        b0 = _mm_unpackhi_epi64(a1, c1);

        c0 = _mm_unpacklo_epi64(b1, d1);

        d0 = _mm_unpackhi_epi64(b1, d1);

        _mm_storeu_si128((__m128i *) &out_b[0*size + ii], a0);

        _mm_storeu_si128((__m128i *) &out_b[1*size + ii], b0);

        _mm_storeu_si128((__m128i *) &out_b[2*size + ii], c0);

        _mm_storeu_si128((__m128i *) &out_b[3*size + ii], d0);

    }

    return blosc_internal_bshuf_trans_byte_elem_remainder(in, out, size, 4,

            size - size % 16);

}

/* Transpose bytes within elements for 64 bit elements. */

static int64_t bshuf_trans_byte_elem_SSE_64(void* in, void* out, const size_t size) {

    char* in_b = (char*) in;

    char* out_b = (char*) out;

    __m128i a0, b0, c0, d0, e0, f0, g0, h0;

    __m128i a1, b1, c1, d1, e1, f1, g1, h1;

    size_t ii;

    for (ii=0; ii + 15 < size; ii += 16) {

        a0 = _mm_loadu_si128((__m128i *) &in_b[8*ii + 0*16]);

        b0 = _mm_loadu_si128((__m128i *) &in_b[8*ii + 1*16]);

        c0 = _mm_loadu_si128((__m128i *) &in_b[8*ii + 2*16]);

        d0 = _mm_loadu_si128((__m128i *) &in_b[8*ii + 3*16]);

        e0 = _mm_loadu_si128((__m128i *) &in_b[8*ii + 4*16]);

        f0 = _mm_loadu_si128((__m128i *) &in_b[8*ii + 5*16]);

        g0 = _mm_loadu_si128((__m128i *) &in_b[8*ii + 6*16]);

        h0 = _mm_loadu_si128((__m128i *) &in_b[8*ii + 7*16]);

        a1 = _mm_unpacklo_epi8(a0, b0);

        b1 = _mm_unpackhi_epi8(a0, b0);

        c1 = _mm_unpacklo_epi8(c0, d0);

        d1 = _mm_unpackhi_epi8(c0, d0);

        e1 = _mm_unpacklo_epi8(e0, f0);

        f1 = _mm_unpackhi_epi8(e0, f0);

        g1 = _mm_unpacklo_epi8(g0, h0);

        h1 = _mm_unpackhi_epi8(g0, h0);

        a0 = _mm_unpacklo_epi8(a1, b1);

        b0 = _mm_unpackhi_epi8(a1, b1);

        c0 = _mm_unpacklo_epi8(c1, d1);

        d0 = _mm_unpackhi_epi8(c1, d1);

        e0 = _mm_unpacklo_epi8(e1, f1);

        f0 = _mm_unpackhi_epi8(e1, f1);

        g0 = _mm_unpacklo_epi8(g1, h1);

        h0 = _mm_unpackhi_epi8(g1, h1);

        a1 = _mm_unpacklo_epi32(a0, c0);

        b1 = _mm_unpackhi_epi32(a0, c0);

        c1 = _mm_unpacklo_epi32(b0, d0);

        d1 = _mm_unpackhi_epi32(b0, d0);

        e1 = _mm_unpacklo_epi32(e0, g0);

        f1 = _mm_unpackhi_epi32(e0, g0);

        g1 = _mm_unpacklo_epi32(f0, h0);

        h1 = _mm_unpackhi_epi32(f0, h0);

        a0 = _mm_unpacklo_epi64(a1, e1);

        b0 = _mm_unpackhi_epi64(a1, e1);

        c0 = _mm_unpacklo_epi64(b1, f1);

        d0 = _mm_unpackhi_epi64(b1, f1);

        e0 = _mm_unpacklo_epi64(c1, g1);

        f0 = _mm_unpackhi_epi64(c1, g1);

        g0 = _mm_unpacklo_epi64(d1, h1);

        h0 = _mm_unpackhi_epi64(d1, h1);

        _mm_storeu_si128((__m128i *) &out_b[0*size + ii], a0);

        _mm_storeu_si128((__m128i *) &out_b[1*size + ii], b0);

        _mm_storeu_si128((__m128i *) &out_b[2*size + ii], c0);

        _mm_storeu_si128((__m128i *) &out_b[3*size + ii], d0);

        _mm_storeu_si128((__m128i *) &out_b[4*size + ii], e0);

        _mm_storeu_si128((__m128i *) &out_b[5*size + ii], f0);

        _mm_storeu_si128((__m128i *) &out_b[6*size + ii], g0);

        _mm_storeu_si128((__m128i *) &out_b[7*size + ii], h0);

    }

    return blosc_internal_bshuf_trans_byte_elem_remainder(in, out, size, 8,

            size - size % 16);

}

/* Memory copy with bshuf call signature. */

static int64_t bshuf_copy(void* in, void* out, const size_t size,

                          const size_t elem_size) {

    char* in_b = (char*) in;

    char* out_b = (char*) out;

    memcpy(out_b, in_b, size * elem_size);

    return size * elem_size;

}

/* Transpose bytes within elements using best SSE algorithm available. */

int64_t blosc_internal_bshuf_trans_byte_elem_sse2(void* in, void* out, const size_t size,

                                                  const size_t elem_size, void* tmp_buf) {

    int64_t count;

    /*  Trivial cases: power of 2 bytes. */

    switch (elem_size) {

        case 1:

            count = bshuf_copy(in, out, size, elem_size);

            return count;

        case 2:

            count = bshuf_trans_byte_elem_SSE_16(in, out, size);

            return count;

        case 4:

            count = bshuf_trans_byte_elem_SSE_32(in, out, size);

            return count;

        case 8:

            count = bshuf_trans_byte_elem_SSE_64(in, out, size);

            return count;

    }

    /*  Worst case: odd number of bytes. Turns out that this is faster for */

    /*  (odd * 2) byte elements as well (hence % 4). */

    if (elem_size % 4) {

        count = blosc_internal_bshuf_trans_byte_elem_scal(in, out, size, elem_size);

        return count;

    }

    /*  Multiple of power of 2: transpose hierarchically. */

    {

        size_t nchunk_elem;

        if ((elem_size % 8) == 0) {

            nchunk_elem = elem_size / 8;

            TRANS_ELEM_TYPE(in, out, size, nchunk_elem, int64_t);

            count = bshuf_trans_byte_elem_SSE_64(out, tmp_buf,

                    size * nchunk_elem);

            blosc_internal_bshuf_trans_elem(tmp_buf, out, 8, nchunk_elem, size);

        } else if ((elem_size % 4) == 0) {

            nchunk_elem = elem_size / 4;

            TRANS_ELEM_TYPE(in, out, size, nchunk_elem, int32_t);

            count = bshuf_trans_byte_elem_SSE_32(out, tmp_buf,

                    size * nchunk_elem);

            blosc_internal_bshuf_trans_elem(tmp_buf, out, 4, nchunk_elem, size);

        } else {

            /*  Not used since scalar algorithm is faster. */

            nchunk_elem = elem_size / 2;

            TRANS_ELEM_TYPE(in, out, size, nchunk_elem, int16_t);

            count = bshuf_trans_byte_elem_SSE_16(out, tmp_buf,

                    size * nchunk_elem);

            blosc_internal_bshuf_trans_elem(tmp_buf, out, 2, nchunk_elem, size);

        }

        return count;

    }

}

/* Transpose bits within bytes. */

static int64_t bshuf_trans_bit_byte_sse2(void* in, void* out, const size_t size,

                                         const size_t elem_size) {

    char* in_b = (char*) in;

    char* out_b = (char*) out;

    uint16_t* out_ui16;

    int64_t count;

    size_t nbyte = elem_size * size;

    __m128i xmm;

    int32_t bt;

    size_t ii, kk;

    CHECK_MULT_EIGHT(nbyte);

    for (ii = 0; ii + 15 < nbyte; ii += 16) {

        xmm = _mm_loadu_si128((__m128i *) &in_b[ii]);

        for (kk = 0; kk < 8; kk++) {

            bt = _mm_movemask_epi8(xmm);

            xmm = _mm_slli_epi16(xmm, 1);

            out_ui16 = (uint16_t*) &out_b[((7 - kk) * nbyte + ii) / 8];

            *out_ui16 = bt;

        }

    }

    count = blosc_internal_bshuf_trans_bit_byte_remainder(in, out, size, elem_size,

            nbyte - nbyte % 16);

    return count;

}

/* Transpose bits within elements. */

int64_t blosc_internal_bshuf_trans_bit_elem_sse2(void* in, void* out, const size_t size,

          const size_t elem_size, void* tmp_buf) {

    int64_t count;

    CHECK_MULT_EIGHT(size);

    count = blosc_internal_bshuf_trans_byte_elem_sse2(in, out, size, elem_size, tmp_buf);

    CHECK_ERR(count);

    count = bshuf_trans_bit_byte_sse2(out, tmp_buf, size, elem_size);

    CHECK_ERR(count);

    count = blosc_internal_bshuf_trans_bitrow_eight(tmp_buf, out, size, elem_size);

    return count;

}

/* For data organized into a row for each bit (8 * elem_size rows), transpose

 * the bytes. */

int64_t blosc_internal_bshuf_trans_byte_bitrow_sse2(void* in, void* out, const size_t size,

             const size_t elem_size) {

    char* in_b = (char*) in;

    char* out_b = (char*) out;

    size_t nrows = 8 * elem_size;

    size_t nbyte_row = size / 8;

    size_t ii, jj;

    __m128i a0, b0, c0, d0, e0, f0, g0, h0;

    __m128i a1, b1, c1, d1, e1, f1, g1, h1;

    __m128 *as, *bs, *cs, *ds, *es, *fs, *gs, *hs;

    CHECK_MULT_EIGHT(size);

    for (ii = 0; ii + 7 < nrows; ii += 8) {

        for (jj = 0; jj + 15 < nbyte_row; jj += 16) {

            a0 = _mm_loadu_si128((__m128i *) &in_b[(ii + 0)*nbyte_row + jj]);

            b0 = _mm_loadu_si128((__m128i *) &in_b[(ii + 1)*nbyte_row + jj]);

            c0 = _mm_loadu_si128((__m128i *) &in_b[(ii + 2)*nbyte_row + jj]);

            d0 = _mm_loadu_si128((__m128i *) &in_b[(ii + 3)*nbyte_row + jj]);

            e0 = _mm_loadu_si128((__m128i *) &in_b[(ii + 4)*nbyte_row + jj]);

            f0 = _mm_loadu_si128((__m128i *) &in_b[(ii + 5)*nbyte_row + jj]);

            g0 = _mm_loadu_si128((__m128i *) &in_b[(ii + 6)*nbyte_row + jj]);

            h0 = _mm_loadu_si128((__m128i *) &in_b[(ii + 7)*nbyte_row + jj]);

            a1 = _mm_unpacklo_epi8(a0, b0);

            b1 = _mm_unpacklo_epi8(c0, d0);

            c1 = _mm_unpacklo_epi8(e0, f0);

            d1 = _mm_unpacklo_epi8(g0, h0);

            e1 = _mm_unpackhi_epi8(a0, b0);

            f1 = _mm_unpackhi_epi8(c0, d0);

            g1 = _mm_unpackhi_epi8(e0, f0);

            h1 = _mm_unpackhi_epi8(g0, h0);

            a0 = _mm_unpacklo_epi16(a1, b1);

            b0 = _mm_unpacklo_epi16(c1, d1);

            c0 = _mm_unpackhi_epi16(a1, b1);

            d0 = _mm_unpackhi_epi16(c1, d1);

            e0 = _mm_unpacklo_epi16(e1, f1);

            f0 = _mm_unpacklo_epi16(g1, h1);

            g0 = _mm_unpackhi_epi16(e1, f1);

            h0 = _mm_unpackhi_epi16(g1, h1);

            a1 = _mm_unpacklo_epi32(a0, b0);

            b1 = _mm_unpackhi_epi32(a0, b0);

            c1 = _mm_unpacklo_epi32(c0, d0);

            d1 = _mm_unpackhi_epi32(c0, d0);

            e1 = _mm_unpacklo_epi32(e0, f0);

            f1 = _mm_unpackhi_epi32(e0, f0);

            g1 = _mm_unpacklo_epi32(g0, h0);

            h1 = _mm_unpackhi_epi32(g0, h0);

            /*  We don't have a storeh instruction for integers, so interpret */

            /*  as a float. Have a storel (_mm_storel_epi64). */

            as = (__m128 *) &a1;

            bs = (__m128 *) &b1;

            cs = (__m128 *) &c1;

            ds = (__m128 *) &d1;

            es = (__m128 *) &e1;

            fs = (__m128 *) &f1;

            gs = (__m128 *) &g1;

            hs = (__m128 *) &h1;

            _mm_storel_pi((__m64 *) &out_b[(jj + 0) * nrows + ii], *as);

            _mm_storel_pi((__m64 *) &out_b[(jj + 2) * nrows + ii], *bs);

            _mm_storel_pi((__m64 *) &out_b[(jj + 4) * nrows + ii], *cs);

            _mm_storel_pi((__m64 *) &out_b[(jj + 6) * nrows + ii], *ds);

            _mm_storel_pi((__m64 *) &out_b[(jj + 8) * nrows + ii], *es);

            _mm_storel_pi((__m64 *) &out_b[(jj + 10) * nrows + ii], *fs);

            _mm_storel_pi((__m64 *) &out_b[(jj + 12) * nrows + ii], *gs);

            _mm_storel_pi((__m64 *) &out_b[(jj + 14) * nrows + ii], *hs);

            _mm_storeh_pi((__m64 *) &out_b[(jj + 1) * nrows + ii], *as);

            _mm_storeh_pi((__m64 *) &out_b[(jj + 3) * nrows + ii], *bs);

            _mm_storeh_pi((__m64 *) &out_b[(jj + 5) * nrows + ii], *cs);

            _mm_storeh_pi((__m64 *) &out_b[(jj + 7) * nrows + ii], *ds);

            _mm_storeh_pi((__m64 *) &out_b[(jj + 9) * nrows + ii], *es);

            _mm_storeh_pi((__m64 *) &out_b[(jj + 11) * nrows + ii], *fs);

            _mm_storeh_pi((__m64 *) &out_b[(jj + 13) * nrows + ii], *gs);

            _mm_storeh_pi((__m64 *) &out_b[(jj + 15) * nrows + ii], *hs);

        }

        for (jj = nbyte_row - nbyte_row % 16; jj < nbyte_row; jj ++) {

            out_b[jj * nrows + ii + 0] = in_b[(ii + 0)*nbyte_row + jj];

            out_b[jj * nrows + ii + 1] = in_b[(ii + 1)*nbyte_row + jj];

            out_b[jj * nrows + ii + 2] = in_b[(ii + 2)*nbyte_row + jj];

            out_b[jj * nrows + ii + 3] = in_b[(ii + 3)*nbyte_row + jj];

            out_b[jj * nrows + ii + 4] = in_b[(ii + 4)*nbyte_row + jj];

            out_b[jj * nrows + ii + 5] = in_b[(ii + 5)*nbyte_row + jj];

            out_b[jj * nrows + ii + 6] = in_b[(ii + 6)*nbyte_row + jj];

            out_b[jj * nrows + ii + 7] = in_b[(ii + 7)*nbyte_row + jj];

        }

    }

    return size * elem_size;

}

/* Shuffle bits within the bytes of eight element blocks. */

int64_t blosc_internal_bshuf_shuffle_bit_eightelem_sse2(void* in, void* out, const size_t size,

           const size_t elem_size) {

    /*  With a bit of care, this could be written such that such that it is */

    /*  in_buf = out_buf safe. */

    char* in_b = (char*) in;

    uint16_t* out_ui16 = (uint16_t*) out;

    size_t nbyte = elem_size * size;

    __m128i xmm;

    int32_t bt;

    size_t ii, jj, kk;

    size_t ind;

    CHECK_MULT_EIGHT(size);

    if (elem_size % 2) {

        blosc_internal_bshuf_shuffle_bit_eightelem_scal(in, out, size, elem_size);

    } else {

        for (ii = 0; ii + 8 * elem_size - 1 < nbyte;

                ii += 8 * elem_size) {

            for (jj = 0; jj + 15 < 8 * elem_size; jj += 16) {

                xmm = _mm_loadu_si128((__m128i *) &in_b[ii + jj]);

                for (kk = 0; kk < 8; kk++) {

                    bt = _mm_movemask_epi8(xmm);

                    xmm = _mm_slli_epi16(xmm, 1);

                    ind = (ii + jj / 8 + (7 - kk) * elem_size);

                    out_ui16[ind / 2] = bt;

                }

            }

        }

    }

    return size * elem_size;

}

/* Untranspose bits within elements. */

int64_t blosc_internal_bshuf_untrans_bit_elem_sse2(void* in, void* out, const size_t size,

            const size_t elem_size, void* tmp_buf) {

    int64_t count;

    CHECK_MULT_EIGHT(size);

    count = blosc_internal_bshuf_trans_byte_bitrow_sse2(in, tmp_buf, size, elem_size);

    CHECK_ERR(count);

    count = blosc_internal_bshuf_shuffle_bit_eightelem_sse2(tmp_buf, out, size, elem_size);

    return count;

}

#endif /* !defined(__SSE2__) */