/*

 * Copyright (c) 2012

 *      MIPS Technologies, Inc., California.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. Neither the name of the MIPS Technologies, Inc., nor the names of its

 *    contributors may be used to endorse or promote products derived from

 *    this software without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE MIPS TECHNOLOGIES, INC. ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE MIPS TECHNOLOGIES, INC. BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 *

 * Author:  Nedeljko Babic (nedeljko.babic imgtec com)

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg 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.

 *

 * FFmpeg 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 FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#include "common.h"

#include "fixed_dsp.h"

#include "mem.h"

static void vector_fmul_add_c(int *dst, const int *src0, const int *src1, const int *src2, int len){

    int i;

    int64_t accu;

    for (i=0; i<len; i++) {

        accu = (int64_t)src0[i] * src1[i];

        dst[i] = src2[i] + (int)((accu + 0x40000000) >> 31);

    }

}

static void vector_fmul_reverse_c(int *dst, const int *src0, const int *src1, int len)

{

    int i;

    int64_t accu;

    src1 += len-1;

    for (i=0; i<len; i++) {

        accu = (int64_t)src0[i] * src1[-i];

        dst[i] = (int)((accu+0x40000000) >> 31);

    }

}

static void vector_fmul_window_scaled_c(int16_t *dst, const int32_t *src0,

                                       const int32_t *src1, const int32_t *win,

                                       int len, uint8_t bits)

{

    int32_t s0, s1, wi, wj, i,j, round;

    dst += len;

    win += len;

    src0+= len;

    round = bits? 1 << (bits-1) : 0;

    for (i=-len, j=len-1; i<0; i++, j--) {

        s0 = src0[i];

        s1 = src1[j];

        wi = win[i];

        wj = win[j];

        dst[i] = av_clip_int16(((((int64_t)s0*wj - (int64_t)s1*wi + 0x40000000) >> 31) + round) >> bits);

        dst[j] = av_clip_int16(((((int64_t)s0*wi + (int64_t)s1*wj + 0x40000000) >> 31) + round) >> bits);

    }

}

static void vector_fmul_window_c(int32_t *dst, const int32_t *src0,

                                       const int32_t *src1, const int32_t *win,

                                       int len)

{

    int32_t s0, s1, wi, wj, i, j;

    dst += len;

    win += len;

    src0+= len;

    for (i=-len, j=len-1; i<0; i++, j--) {

        s0 = src0[i];

        s1 = src1[j];

        wi = win[i];

        wj = win[j];

        dst[i] = ((int64_t)s0*wj - (int64_t)s1*wi + 0x40000000) >> 31;

        dst[j] = ((int64_t)s0*wi + (int64_t)s1*wj + 0x40000000) >> 31;

    }

}

static void vector_fmul_c(int *dst, const int *src0, const int *src1, int len)

{

    int i;

    int64_t accu;

    for (i = 0; i < len; i++){

        accu = (int64_t)src0[i] * src1[i];

        dst[i] = (int)((accu+0x40000000) >> 31);

    }

}

static int scalarproduct_fixed_c(const int *v1, const int *v2, int len)

{

    /** p is initialized with 0x40000000 so that the proper rounding will occur

      * at the end */

    int64_t p = 0x40000000;

    int i;

    for (i = 0; i < len; i++)

        p += (int64_t)v1[i] * v2[i];

    return (int)(p >> 31);

}

static void butterflies_fixed_c(int *restrict v1s, int *restrict v2, int len)

{

    int i;

    unsigned int *v1 = v1s;

    for (i = 0; i < len; i++){

        int t = v1[i] - v2[i];

        v1[i] += v2[i];

        v2[i] = t;

    }

}

AVFixedDSPContext * avpriv_alloc_fixed_dsp(int bit_exact)

{

    AVFixedDSPContext * fdsp = av_malloc(sizeof(AVFixedDSPContext));

    if (!fdsp)

        return NULL;

    fdsp->vector_fmul_window_scaled = vector_fmul_window_scaled_c;

    fdsp->vector_fmul_window = vector_fmul_window_c;

    fdsp->vector_fmul = vector_fmul_c;

    fdsp->vector_fmul_add = vector_fmul_add_c;

    fdsp->vector_fmul_reverse = vector_fmul_reverse_c;

    fdsp->butterflies_fixed = butterflies_fixed_c;

    fdsp->scalarproduct_fixed = scalarproduct_fixed_c;

#if ARCH_RISCV

    ff_fixed_dsp_init_riscv(fdsp);

#elif ARCH_X86 && HAVE_X86ASM

    ff_fixed_dsp_init_x86(fdsp);

#endif

    return fdsp;

}