/*

 * Copyright (c) 2018, Alliance for Open Media. All rights reserved.

 *

 * This source code is subject to the terms of the BSD 2 Clause License and

 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License

 * was not distributed with this source code in the LICENSE file, you can

 * obtain it at www.aomedia.org/license/software. If the Alliance for Open

 * Media Patent License 1.0 was not distributed with this source code in the

 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.

 */

#include <assert.h>

#include <immintrin.h>

#include "config/aom_config.h"

#include "config/aom_dsp_rtcd.h"

#include "aom_ports/mem.h"

#include "aom/aom_integer.h"

#include "aom_dsp/aom_dsp_common.h"

#include "aom_dsp/aom_filter.h"

#include "aom_dsp/x86/obmc_intrinsic_sse4.h"

////////////////////////////////////////////////////////////////////////////////

// 8 bit

////////////////////////////////////////////////////////////////////////////////

static inline void obmc_variance_w8n(const uint8_t *pre, const int pre_stride,

                                     const int32_t *wsrc, const int32_t *mask,

                                     unsigned int *const sse, int *const sum,

                                     const int w, const int h) {

  int n = 0, width, height = h;

  __m128i v_sum_d = _mm_setzero_si128();

  __m128i v_sse_d = _mm_setzero_si128();

  const __m256i v_bias_d = _mm256_set1_epi32((1 << 12) >> 1);

  __m128i v_d;

  const uint8_t *pre_temp;

  assert(w >= 8);

  assert(IS_POWER_OF_TWO(w));

  assert(IS_POWER_OF_TWO(h));

  do {

    width = w;

    pre_temp = pre;

    do {

      const __m128i v_p_b = _mm_loadl_epi64((const __m128i *)pre_temp);

      const __m256i v_m_d = _mm256_loadu_si256((__m256i const *)(mask + n));

      const __m256i v_w_d = _mm256_loadu_si256((__m256i const *)(wsrc + n));

      const __m256i v_p0_d = _mm256_cvtepu8_epi32(v_p_b);

      // Values in both pre and mask fit in 15 bits, and are packed at 32 bit

      // boundaries. We use pmaddwd, as it has lower latency on Haswell

      // than pmulld but produces the same result with these inputs.

      const __m256i v_pm_d = _mm256_madd_epi16(v_p0_d, v_m_d);

      const __m256i v_diff0_d = _mm256_sub_epi32(v_w_d, v_pm_d);

      const __m256i v_sign_d = _mm256_srai_epi32(v_diff0_d, 31);

      const __m256i v_tmp_d =

          _mm256_add_epi32(_mm256_add_epi32(v_diff0_d, v_bias_d), v_sign_d);

      const __m256i v_rdiff0_d = _mm256_srai_epi32(v_tmp_d, 12);

      const __m128i v_rdiff_d = _mm256_castsi256_si128(v_rdiff0_d);

      const __m128i v_rdiff1_d = _mm256_extracti128_si256(v_rdiff0_d, 1);

      const __m128i v_rdiff01_w = _mm_packs_epi32(v_rdiff_d, v_rdiff1_d);

      const __m128i v_sqrdiff_d = _mm_madd_epi16(v_rdiff01_w, v_rdiff01_w);

      v_sum_d = _mm_add_epi32(v_sum_d, v_rdiff_d);

      v_sum_d = _mm_add_epi32(v_sum_d, v_rdiff1_d);

      v_sse_d = _mm_add_epi32(v_sse_d, v_sqrdiff_d);

      pre_temp += 8;

      n += 8;

      width -= 8;

    } while (width > 0);

    pre += pre_stride;

    height -= 1;

  } while (height > 0);

  v_d = _mm_hadd_epi32(v_sum_d, v_sse_d);

  v_d = _mm_hadd_epi32(v_d, v_d);

  *sum = _mm_cvtsi128_si32(v_d);

  *sse = (unsigned int)_mm_cvtsi128_si32(_mm_srli_si128(v_d, 4));

}

static inline void obmc_variance_w16n(const uint8_t *pre, const int pre_stride,

                                      const int32_t *wsrc, const int32_t *mask,

                                      unsigned int *const sse, int *const sum,

                                      const int w, const int h) {

  int n = 0, width, height = h;

  __m256i v_d;

  __m128i res0;

  const uint8_t *pre_temp;

  const __m256i v_bias_d = _mm256_set1_epi32((1 << 12) >> 1);

  __m256i v_sum_d = _mm256_setzero_si256();

  __m256i v_sse_d = _mm256_setzero_si256();

  assert(w >= 16);

  assert(IS_POWER_OF_TWO(w));

  assert(IS_POWER_OF_TWO(h));

  do {

    width = w;

    pre_temp = pre;

    do {

      const __m128i v_p_b = _mm_loadu_si128((__m128i *)pre_temp);

      const __m256i v_m0_d = _mm256_loadu_si256((__m256i const *)(mask + n));

      const __m256i v_w0_d = _mm256_loadu_si256((__m256i const *)(wsrc + n));

      const __m256i v_m1_d =

          _mm256_loadu_si256((__m256i const *)(mask + n + 8));

      const __m256i v_w1_d =

          _mm256_loadu_si256((__m256i const *)(wsrc + n + 8));

      const __m256i v_p0_d = _mm256_cvtepu8_epi32(v_p_b);

      const __m256i v_p1_d = _mm256_cvtepu8_epi32(_mm_srli_si128(v_p_b, 8));

      const __m256i v_pm0_d = _mm256_madd_epi16(v_p0_d, v_m0_d);

      const __m256i v_pm1_d = _mm256_madd_epi16(v_p1_d, v_m1_d);

      const __m256i v_diff0_d = _mm256_sub_epi32(v_w0_d, v_pm0_d);

      const __m256i v_diff1_d = _mm256_sub_epi32(v_w1_d, v_pm1_d);

      const __m256i v_sign0_d = _mm256_srai_epi32(v_diff0_d, 31);

      const __m256i v_sign1_d = _mm256_srai_epi32(v_diff1_d, 31);

      const __m256i v_tmp0_d =

          _mm256_add_epi32(_mm256_add_epi32(v_diff0_d, v_bias_d), v_sign0_d);

      const __m256i v_tmp1_d =

          _mm256_add_epi32(_mm256_add_epi32(v_diff1_d, v_bias_d), v_sign1_d);

      const __m256i v_rdiff0_d = _mm256_srai_epi32(v_tmp0_d, 12);

      const __m256i v_rdiff2_d = _mm256_srai_epi32(v_tmp1_d, 12);

      const __m256i v_rdiff1_d = _mm256_add_epi32(v_rdiff0_d, v_rdiff2_d);

      const __m256i v_rdiff01_w = _mm256_packs_epi32(v_rdiff0_d, v_rdiff2_d);

      const __m256i v_sqrdiff_d = _mm256_madd_epi16(v_rdiff01_w, v_rdiff01_w);

      v_sum_d = _mm256_add_epi32(v_sum_d, v_rdiff1_d);

      v_sse_d = _mm256_add_epi32(v_sse_d, v_sqrdiff_d);

      pre_temp += 16;

      n += 16;

      width -= 16;

    } while (width > 0);

    pre += pre_stride;

    height -= 1;

  } while (height > 0);

  v_d = _mm256_hadd_epi32(v_sum_d, v_sse_d);

  v_d = _mm256_hadd_epi32(v_d, v_d);

  res0 = _mm256_castsi256_si128(v_d);

  res0 = _mm_add_epi32(res0, _mm256_extractf128_si256(v_d, 1));

  *sum = _mm_cvtsi128_si32(res0);

  *sse = (unsigned int)_mm_cvtsi128_si32(_mm_srli_si128(res0, 4));

}

#define OBMCVARWXH(W, H)                                                \

  unsigned int aom_obmc_variance##W##x##H##_avx2(                       \

      const uint8_t *pre, int pre_stride, const int32_t *wsrc,          \

      const int32_t *mask, unsigned int *sse) {                         \

    int sum;                                                            \

    if (W == 4) {                                                       \

      obmc_variance_w4(pre, pre_stride, wsrc, mask, sse, &sum, H);      \

    } else if (W == 8) {                                                \

      obmc_variance_w8n(pre, pre_stride, wsrc, mask, sse, &sum, W, H);  \

    } else {                                                            \

      obmc_variance_w16n(pre, pre_stride, wsrc, mask, sse, &sum, W, H); \

    }                                                                   \

                                                                        \

    return *sse - (unsigned int)(((int64_t)sum * sum) / (W * H));       \

  }

Unexecuted instantiation: aom_obmc_variance128x128_avx2

Unexecuted instantiation: aom_obmc_variance128x64_avx2

Unexecuted instantiation: aom_obmc_variance64x128_avx2

Unexecuted instantiation: aom_obmc_variance64x64_avx2

Unexecuted instantiation: aom_obmc_variance64x32_avx2

Unexecuted instantiation: aom_obmc_variance32x64_avx2

Unexecuted instantiation: aom_obmc_variance32x32_avx2

Unexecuted instantiation: aom_obmc_variance32x16_avx2

Unexecuted instantiation: aom_obmc_variance16x32_avx2

Unexecuted instantiation: aom_obmc_variance16x16_avx2

Unexecuted instantiation: aom_obmc_variance16x8_avx2

Unexecuted instantiation: aom_obmc_variance8x16_avx2

Unexecuted instantiation: aom_obmc_variance8x8_avx2

Unexecuted instantiation: aom_obmc_variance8x4_avx2

Unexecuted instantiation: aom_obmc_variance4x8_avx2

Unexecuted instantiation: aom_obmc_variance4x4_avx2

Unexecuted instantiation: aom_obmc_variance4x16_avx2

Unexecuted instantiation: aom_obmc_variance16x4_avx2

Unexecuted instantiation: aom_obmc_variance8x32_avx2

Unexecuted instantiation: aom_obmc_variance32x8_avx2

Unexecuted instantiation: aom_obmc_variance16x64_avx2

Unexecuted instantiation: aom_obmc_variance64x16_avx2

OBMCVARWXH(128, 128)

OBMCVARWXH(128, 64)

OBMCVARWXH(64, 128)

OBMCVARWXH(64, 64)

OBMCVARWXH(64, 32)

OBMCVARWXH(32, 64)

OBMCVARWXH(32, 32)

OBMCVARWXH(32, 16)

OBMCVARWXH(16, 32)

OBMCVARWXH(16, 16)

OBMCVARWXH(16, 8)

OBMCVARWXH(8, 16)

OBMCVARWXH(8, 8)

OBMCVARWXH(8, 4)

OBMCVARWXH(4, 8)

OBMCVARWXH(4, 4)

OBMCVARWXH(4, 16)

OBMCVARWXH(16, 4)

OBMCVARWXH(8, 32)

OBMCVARWXH(32, 8)

OBMCVARWXH(16, 64)

OBMCVARWXH(64, 16)