/*
  * 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 "fixed_dsp.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 *v1, int *v2, int len)
 {
     int i;
 
     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_X86)
         ff_fixed_dsp_init_x86(fdsp);
 

     return fdsp;
 }