/*****************************************************************************
 * This file is part of Kvazaar HEVC encoder.
 *
 * Copyright (C) 2013-2014 Tampere University of Technology and others (see
 * COPYING file).
 *
 * Kvazaar is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 *
 * Kvazaar 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Kvazaar.  If not, see <http://www.gnu.org/licenses/>.
 ****************************************************************************/

/*
 * \file
 */
#include "../strategyselector.h"
#include "../image.h"
#include <immintrin.h>
#include <assert.h>

#ifdef __GNUC__
  __attribute__ ((__target__ ("sse2")))
#endif
static unsigned reg_sad_sse2(const pixel * const data1, const pixel * const data2,
                        const int width, const int height, const unsigned stride1, const unsigned stride2)
{
  int y, x;
  unsigned sad = 0;
  __m128i sse_inc = _mm_setzero_si128 ();
  long long int sse_inc_array[2];
  
  for (y = 0; y < height; ++y) {
    for (x = 0; x <= width-16; x+=16) {
      const __m128i a = _mm_loadu_si128((__m128i const*) &data1[y * stride1 + x]);
      const __m128i b = _mm_loadu_si128((__m128i const*) &data2[y * stride2 + x]);
      sse_inc = _mm_add_epi32(sse_inc, _mm_sad_epu8(a,b));
    }

    for (; x < width; ++x) {
      sad += abs(data1[y * stride1 + x] - data2[y * stride2 + x]);
    }
  }
  _mm_storeu_si128((__m128i*) sse_inc_array, sse_inc);
  sad += sse_inc_array[0] + sse_inc_array[1];

  return sad;
}

static int strategy_register_picture_sse2(void* opaque) {
  return strategyselector_register(opaque, "reg_sad", "sse2", 10, &reg_sad_sse2);
}