/*

 * Copyright (c) 2019, 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 <immintrin.h>

#include "config/aom_dsp_rtcd.h"

#include "aom/aom_integer.h"

#include "aom_dsp/quantize.h"

#include "aom_dsp/x86/quantize_x86.h"

static inline void load_b_values_avx2(const int16_t *zbin_ptr, __m256i *zbin,

                                      const int16_t *round_ptr, __m256i *round,

                                      const int16_t *quant_ptr, __m256i *quant,

                                      const int16_t *dequant_ptr,

                                      __m256i *dequant,

                                      const int16_t *shift_ptr,

                                      __m256i *shift) {

  *zbin = _mm256_castsi128_si256(_mm_load_si128((const __m128i *)zbin_ptr));

  *zbin = _mm256_permute4x64_epi64(*zbin, 0x54);

  *zbin = _mm256_sub_epi16(*zbin, _mm256_set1_epi16(1));

  *round = _mm256_castsi128_si256(_mm_load_si128((const __m128i *)round_ptr));

  *round = _mm256_permute4x64_epi64(*round, 0x54);

  *quant = _mm256_castsi128_si256(_mm_load_si128((const __m128i *)quant_ptr));

  *quant = _mm256_permute4x64_epi64(*quant, 0x54);

  *dequant =

      _mm256_castsi128_si256(_mm_load_si128((const __m128i *)dequant_ptr));

  *dequant = _mm256_permute4x64_epi64(*dequant, 0x54);

  *shift = _mm256_castsi128_si256(_mm_load_si128((const __m128i *)shift_ptr));

  *shift = _mm256_permute4x64_epi64(*shift, 0x54);

}

static inline __m256i load_coefficients_avx2(const tran_low_t *coeff_ptr) {

  const __m256i coeff1 = _mm256_load_si256((__m256i *)(coeff_ptr));

  const __m256i coeff2 = _mm256_load_si256((__m256i *)(coeff_ptr + 8));

  return _mm256_packs_epi32(coeff1, coeff2);

}

static inline void update_mask1_avx2(__m256i *cmp_mask,

                                     const int16_t *iscan_ptr, int *is_found,

                                     __m256i *mask) {

  __m256i temp_mask = _mm256_setzero_si256();

  if (_mm256_movemask_epi8(*cmp_mask)) {

    __m256i iscan = _mm256_loadu_si256((const __m256i *)(iscan_ptr));

    temp_mask = _mm256_and_si256(*cmp_mask, iscan);

    *is_found = 1;

  }

  *mask = _mm256_max_epi16(temp_mask, *mask);

}

static inline void update_mask0_avx2(__m256i *qcoeff, __m256i *threshold,

                                     const int16_t *iscan_ptr, int *is_found,

                                     __m256i *mask) {

  __m256i zero = _mm256_setzero_si256();

  __m256i coeff[2], cmp_mask0, cmp_mask1;

  coeff[0] = _mm256_unpacklo_epi16(*qcoeff, zero);

  coeff[1] = _mm256_unpackhi_epi16(*qcoeff, zero);

  coeff[0] = _mm256_slli_epi32(coeff[0], AOM_QM_BITS);

  cmp_mask0 = _mm256_cmpgt_epi32(coeff[0], threshold[0]);

  coeff[1] = _mm256_slli_epi32(coeff[1], AOM_QM_BITS);

  cmp_mask1 = _mm256_cmpgt_epi32(coeff[1], threshold[1]);

  cmp_mask0 =

      _mm256_permute4x64_epi64(_mm256_packs_epi32(cmp_mask0, cmp_mask1), 0xd8);

  update_mask1_avx2(&cmp_mask0, iscan_ptr, is_found, mask);

}

static inline void calculate_qcoeff_avx2(__m256i *coeff, const __m256i *round,

                                         const __m256i *quant,

                                         const __m256i *shift) {

  __m256i tmp, qcoeff;

  qcoeff = _mm256_adds_epi16(*coeff, *round);

  tmp = _mm256_mulhi_epi16(qcoeff, *quant);

  qcoeff = _mm256_add_epi16(tmp, qcoeff);

  *coeff = _mm256_mulhi_epi16(qcoeff, *shift);

}

static inline __m256i calculate_dqcoeff_avx2(__m256i qcoeff, __m256i dequant) {

  return _mm256_mullo_epi16(qcoeff, dequant);

}

static inline void store_coefficients_avx2(__m256i coeff_vals,

                                           tran_low_t *coeff_ptr) {

  __m256i coeff_sign = _mm256_srai_epi16(coeff_vals, 15);

  __m256i coeff_vals_lo = _mm256_unpacklo_epi16(coeff_vals, coeff_sign);

  __m256i coeff_vals_hi = _mm256_unpackhi_epi16(coeff_vals, coeff_sign);

  _mm256_store_si256((__m256i *)(coeff_ptr), coeff_vals_lo);

  _mm256_store_si256((__m256i *)(coeff_ptr + 8), coeff_vals_hi);

}

void aom_quantize_b_adaptive_avx2(

    const tran_low_t *coeff_ptr, intptr_t n_coeffs, const int16_t *zbin_ptr,

    const int16_t *round_ptr, const int16_t *quant_ptr,

    const int16_t *quant_shift_ptr, tran_low_t *qcoeff_ptr,

    tran_low_t *dqcoeff_ptr, const int16_t *dequant_ptr, uint16_t *eob_ptr,

    const int16_t *scan, const int16_t *iscan) {

  int index = 16;

  int non_zero_count = 0;

  int non_zero_count_prescan_add_zero = 0;

  int is_found0 = 0, is_found1 = 0;

  int eob = -1;

  const __m256i zero = _mm256_setzero_si256();

  __m256i zbin, round, quant, dequant, shift;

  __m256i coeff, qcoeff;

  __m256i cmp_mask, mask0 = zero, mask1 = zero;

  __m128i temp_mask0, temp_mask1;

  int prescan_add[2];

  int thresh[2];

  const qm_val_t wt = (1 << AOM_QM_BITS);

  for (int i = 0; i < 2; ++i) {

    prescan_add[i] = ROUND_POWER_OF_TWO(dequant_ptr[i] * EOB_FACTOR, 7);

    thresh[i] = (zbin_ptr[i] * wt + prescan_add[i]) - 1;

  }

  __m256i threshold[2];

  threshold[0] = _mm256_set1_epi32(thresh[0]);

  threshold[1] = _mm256_set1_epi32(thresh[1]);

  threshold[0] = _mm256_blend_epi32(threshold[0], threshold[1], 0xfe);

#if SKIP_EOB_FACTOR_ADJUST

  int first = -1;

#endif

  // Setup global values.

  load_b_values_avx2(zbin_ptr, &zbin, round_ptr, &round, quant_ptr, &quant,

                     dequant_ptr, &dequant, quant_shift_ptr, &shift);

  // Do DC and first 15 AC.

  coeff = load_coefficients_avx2(coeff_ptr);

  qcoeff = _mm256_abs_epi16(coeff);

  update_mask0_avx2(&qcoeff, threshold, iscan, &is_found0, &mask0);

  __m256i temp0 = _mm256_cmpgt_epi16(qcoeff, zbin);

  zbin = _mm256_unpackhi_epi64(zbin, zbin);

  cmp_mask = _mm256_permute4x64_epi64(temp0, 0xd8);

  update_mask1_avx2(&cmp_mask, iscan, &is_found1, &mask1);

  threshold[0] = threshold[1];

  if (_mm256_movemask_epi8(cmp_mask) == 0) {

    _mm256_store_si256((__m256i *)(qcoeff_ptr), zero);

    _mm256_store_si256((__m256i *)(qcoeff_ptr + 8), zero);

    _mm256_store_si256((__m256i *)(dqcoeff_ptr), zero);

    _mm256_store_si256((__m256i *)(dqcoeff_ptr + 8), zero);

    round = _mm256_unpackhi_epi64(round, round);

    quant = _mm256_unpackhi_epi64(quant, quant);

    shift = _mm256_unpackhi_epi64(shift, shift);

    dequant = _mm256_unpackhi_epi64(dequant, dequant);

  } else {

    calculate_qcoeff_avx2(&qcoeff, &round, &quant, &shift);

    round = _mm256_unpackhi_epi64(round, round);

    quant = _mm256_unpackhi_epi64(quant, quant);

    shift = _mm256_unpackhi_epi64(shift, shift);

    // Reinsert signs

    qcoeff = _mm256_sign_epi16(qcoeff, coeff);

    // Mask out zbin threshold coeffs

    qcoeff = _mm256_and_si256(qcoeff, temp0);

    store_coefficients_avx2(qcoeff, qcoeff_ptr);

    coeff = calculate_dqcoeff_avx2(qcoeff, dequant);

    dequant = _mm256_unpackhi_epi64(dequant, dequant);

    store_coefficients_avx2(coeff, dqcoeff_ptr);

  }

  // AC only loop.

  while (index < n_coeffs) {

    coeff = load_coefficients_avx2(coeff_ptr + index);

    qcoeff = _mm256_abs_epi16(coeff);

    update_mask0_avx2(&qcoeff, threshold, iscan + index, &is_found0, &mask0);

    temp0 = _mm256_cmpgt_epi16(qcoeff, zbin);

    cmp_mask = _mm256_permute4x64_epi64(temp0, 0xd8);

    update_mask1_avx2(&cmp_mask, iscan + index, &is_found1, &mask1);

    if (_mm256_movemask_epi8(cmp_mask) == 0) {

      _mm256_store_si256((__m256i *)(qcoeff_ptr + index), zero);

      _mm256_store_si256((__m256i *)(qcoeff_ptr + index + 8), zero);

      _mm256_store_si256((__m256i *)(dqcoeff_ptr + index), zero);

      _mm256_store_si256((__m256i *)(dqcoeff_ptr + index + 8), zero);

      index += 16;

      continue;

    }

    calculate_qcoeff_avx2(&qcoeff, &round, &quant, &shift);

    qcoeff = _mm256_sign_epi16(qcoeff, coeff);

    qcoeff = _mm256_and_si256(qcoeff, temp0);

    store_coefficients_avx2(qcoeff, qcoeff_ptr + index);

    coeff = calculate_dqcoeff_avx2(qcoeff, dequant);

    store_coefficients_avx2(coeff, dqcoeff_ptr + index);

    index += 16;

  }

  if (is_found0) {

    temp_mask0 = _mm_max_epi16(_mm256_castsi256_si128(mask0),

                               _mm256_extracti128_si256(mask0, 1));

    non_zero_count = calculate_non_zero_count(temp_mask0);

  }

  if (is_found1) {

    temp_mask1 = _mm_max_epi16(_mm256_castsi256_si128(mask1),

                               _mm256_extracti128_si256(mask1, 1));

    non_zero_count_prescan_add_zero = calculate_non_zero_count(temp_mask1);

  }

  for (int i = non_zero_count_prescan_add_zero - 1; i >= non_zero_count; i--) {

    const int rc = scan[i];

    qcoeff_ptr[rc] = 0;

    dqcoeff_ptr[rc] = 0;

  }

  for (int i = non_zero_count - 1; i >= 0; i--) {

    const int rc = scan[i];

    if (qcoeff_ptr[rc]) {

      eob = i;

      break;

    }

  }

  *eob_ptr = eob + 1;

#if SKIP_EOB_FACTOR_ADJUST

  // TODO(Aniket): Experiment the following loop with intrinsic by combining

  // with the quantization loop above

  for (int i = 0; i < non_zero_count; i++) {

    const int rc = scan[i];

    const int qcoeff0 = qcoeff_ptr[rc];

    if (qcoeff0) {

      first = i;

      break;

    }

  }

  if ((*eob_ptr - 1) >= 0 && first == (*eob_ptr - 1)) {

    const int rc = scan[(*eob_ptr - 1)];

    if (qcoeff_ptr[rc] == 1 || qcoeff_ptr[rc] == -1) {

      const int coeff0 = coeff_ptr[rc] * wt;

      const int coeff_sign = AOMSIGN(coeff0);

      const int abs_coeff = (coeff0 ^ coeff_sign) - coeff_sign;

      const int factor = EOB_FACTOR + SKIP_EOB_FACTOR_ADJUST;

      const int prescan_add_val =

          ROUND_POWER_OF_TWO(dequant_ptr[rc != 0] * factor, 7);

      if (abs_coeff <

          (zbin_ptr[rc != 0] * (1 << AOM_QM_BITS) + prescan_add_val)) {

        qcoeff_ptr[rc] = 0;

        dqcoeff_ptr[rc] = 0;

        *eob_ptr = 0;

      }

    }

  }

#endif

}