/*

 * Copyright (c) 2017, 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/av1_rtcd.h"

#include "aom/aom_integer.h"

#include "aom_dsp/aom_dsp_common.h"

static inline void write_zero(tran_low_t *qcoeff) {

  const __m256i zero = _mm256_setzero_si256();

  _mm256_storeu_si256((__m256i *)qcoeff, zero);

  _mm256_storeu_si256((__m256i *)qcoeff + 1, zero);

}

static inline void init_one_qp(const __m128i *p, __m256i *qp) {

  const __m128i ac = _mm_unpackhi_epi64(*p, *p);

  *qp = _mm256_insertf128_si256(_mm256_castsi128_si256(*p), ac, 1);

}

static inline void init_qp(const int16_t *round_ptr, const int16_t *quant_ptr,

                           const int16_t *dequant_ptr, int log_scale,

                           __m256i *thr, __m256i *qp) {

  __m128i round = _mm_loadu_si128((const __m128i *)round_ptr);

  const __m128i quant = _mm_loadu_si128((const __m128i *)quant_ptr);

  const __m128i dequant = _mm_loadu_si128((const __m128i *)dequant_ptr);

  if (log_scale > 0) {

    const __m128i rnd = _mm_set1_epi16((int16_t)1 << (log_scale - 1));

    round = _mm_add_epi16(round, rnd);

    round = _mm_srai_epi16(round, log_scale);

  }

  init_one_qp(&round, &qp[0]);

  init_one_qp(&quant, &qp[1]);

  if (log_scale == 1) {

    qp[1] = _mm256_slli_epi16(qp[1], log_scale);

  }

  init_one_qp(&dequant, &qp[2]);

  *thr = _mm256_srai_epi16(qp[2], 1 + log_scale);

  // Subtracting 1 here eliminates a _mm256_cmpeq_epi16() instruction when

  // calculating the zbin mask.

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

}

static inline void update_qp(__m256i *thr, __m256i *qp) {

  qp[0] = _mm256_permute2x128_si256(qp[0], qp[0], 0x11);

  qp[1] = _mm256_permute2x128_si256(qp[1], qp[1], 0x11);

  qp[2] = _mm256_permute2x128_si256(qp[2], qp[2], 0x11);

  *thr = _mm256_permute2x128_si256(*thr, *thr, 0x11);

}

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 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);

}

static inline uint16_t quant_gather_eob(__m256i eob) {

  const __m128i eob_lo = _mm256_castsi256_si128(eob);

  const __m128i eob_hi = _mm256_extractf128_si256(eob, 1);

  __m128i eob_s = _mm_max_epi16(eob_lo, eob_hi);

  eob_s = _mm_subs_epu16(_mm_set1_epi16(INT16_MAX), eob_s);

  eob_s = _mm_minpos_epu16(eob_s);

  return INT16_MAX - _mm_extract_epi16(eob_s, 0);

}

static inline int16_t accumulate_eob256(__m256i eob256) {

  const __m128i eob_lo = _mm256_castsi256_si128(eob256);

  const __m128i eob_hi = _mm256_extractf128_si256(eob256, 1);

  __m128i eob = _mm_max_epi16(eob_lo, eob_hi);

  __m128i eob_shuffled = _mm_shuffle_epi32(eob, 0xe);

  eob = _mm_max_epi16(eob, eob_shuffled);

  eob_shuffled = _mm_shufflelo_epi16(eob, 0xe);

  eob = _mm_max_epi16(eob, eob_shuffled);

  eob_shuffled = _mm_shufflelo_epi16(eob, 0x1);

  eob = _mm_max_epi16(eob, eob_shuffled);

  return _mm_extract_epi16(eob, 1);

}

static AOM_FORCE_INLINE void quantize_lp_16_first(

    const int16_t *coeff_ptr, const int16_t *iscan_ptr, int16_t *qcoeff_ptr,

    int16_t *dqcoeff_ptr, __m256i *round256, __m256i *quant256,

    __m256i *dequant256, __m256i *eob) {

  const __m256i coeff = _mm256_loadu_si256((const __m256i *)coeff_ptr);

  const __m256i abs_coeff = _mm256_abs_epi16(coeff);

  const __m256i tmp_rnd = _mm256_adds_epi16(abs_coeff, *round256);

  const __m256i abs_qcoeff = _mm256_mulhi_epi16(tmp_rnd, *quant256);

  const __m256i qcoeff = _mm256_sign_epi16(abs_qcoeff, coeff);

  const __m256i dqcoeff = _mm256_mullo_epi16(qcoeff, *dequant256);

  const __m256i nz_mask =

      _mm256_cmpgt_epi16(abs_qcoeff, _mm256_setzero_si256());

  _mm256_storeu_si256((__m256i *)qcoeff_ptr, qcoeff);

  _mm256_storeu_si256((__m256i *)dqcoeff_ptr, dqcoeff);

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

  const __m256i iscan_plus1 = _mm256_sub_epi16(iscan, nz_mask);

  const __m256i nz_iscan = _mm256_and_si256(iscan_plus1, nz_mask);

  *eob = _mm256_max_epi16(*eob, nz_iscan);

}

static AOM_FORCE_INLINE void quantize_lp_16(

    const int16_t *coeff_ptr, intptr_t n_coeffs, const int16_t *iscan_ptr,

    int16_t *qcoeff_ptr, int16_t *dqcoeff_ptr, __m256i *round256,

    __m256i *quant256, __m256i *dequant256, __m256i *eob) {

  const __m256i coeff =

      _mm256_loadu_si256((const __m256i *)(coeff_ptr + n_coeffs));

  const __m256i abs_coeff = _mm256_abs_epi16(coeff);

  const __m256i tmp_rnd = _mm256_adds_epi16(abs_coeff, *round256);

  const __m256i abs_qcoeff = _mm256_mulhi_epi16(tmp_rnd, *quant256);

  const __m256i qcoeff = _mm256_sign_epi16(abs_qcoeff, coeff);

  const __m256i dqcoeff = _mm256_mullo_epi16(qcoeff, *dequant256);

  const __m256i nz_mask =

      _mm256_cmpgt_epi16(abs_qcoeff, _mm256_setzero_si256());

  _mm256_storeu_si256((__m256i *)(qcoeff_ptr + n_coeffs), qcoeff);

  _mm256_storeu_si256((__m256i *)(dqcoeff_ptr + n_coeffs), dqcoeff);

  const __m256i iscan =

      _mm256_loadu_si256((const __m256i *)(iscan_ptr + n_coeffs));

  const __m256i iscan_plus1 = _mm256_sub_epi16(iscan, nz_mask);

  const __m256i nz_iscan = _mm256_and_si256(iscan_plus1, nz_mask);

  *eob = _mm256_max_epi16(*eob, nz_iscan);

}

void av1_quantize_lp_avx2(const int16_t *coeff_ptr, intptr_t n_coeffs,

                          const int16_t *round_ptr, const int16_t *quant_ptr,

                          int16_t *qcoeff_ptr, int16_t *dqcoeff_ptr,

                          const int16_t *dequant_ptr, uint16_t *eob_ptr,

                          const int16_t *scan, const int16_t *iscan) {

  (void)scan;

  __m256i eob256 = _mm256_setzero_si256();

  // Setup global values.

  __m256i round256 =

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

  __m256i quant256 =

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

  __m256i dequant256 =

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

  // Populate upper AC values.

  round256 = _mm256_permute4x64_epi64(round256, 0x54);

  quant256 = _mm256_permute4x64_epi64(quant256, 0x54);

  dequant256 = _mm256_permute4x64_epi64(dequant256, 0x54);

  // Process DC and the first 15 AC coeffs.

  quantize_lp_16_first(coeff_ptr, iscan, qcoeff_ptr, dqcoeff_ptr, &round256,

                       &quant256, &dequant256, &eob256);

  if (n_coeffs > 16) {

    // Overwrite the DC constants with AC constants

    dequant256 = _mm256_permute2x128_si256(dequant256, dequant256, 0x31);

    quant256 = _mm256_permute2x128_si256(quant256, quant256, 0x31);

    round256 = _mm256_permute2x128_si256(round256, round256, 0x31);

    // AC only loop.

    for (int idx = 16; idx < n_coeffs; idx += 16) {

      quantize_lp_16(coeff_ptr, idx, iscan, qcoeff_ptr, dqcoeff_ptr, &round256,

                     &quant256, &dequant256, &eob256);

    }

  }

  *eob_ptr = accumulate_eob256(eob256);

}

static AOM_FORCE_INLINE __m256i get_max_lane_eob(const int16_t *iscan,

                                                 __m256i v_eobmax,

                                                 __m256i v_mask) {

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

  const __m256i v_iscan_perm = _mm256_permute4x64_epi64(v_iscan, 0xD8);

  const __m256i v_iscan_plus1 = _mm256_sub_epi16(v_iscan_perm, v_mask);

  const __m256i v_nz_iscan = _mm256_and_si256(v_iscan_plus1, v_mask);

  return _mm256_max_epi16(v_eobmax, v_nz_iscan);

}

static AOM_FORCE_INLINE void quantize_fp_16(

    const __m256i *thr, const __m256i *qp, const tran_low_t *coeff_ptr,

    const int16_t *iscan_ptr, tran_low_t *qcoeff_ptr, tran_low_t *dqcoeff_ptr,

    __m256i *eob) {

  const __m256i coeff = load_coefficients_avx2(coeff_ptr);

  const __m256i abs_coeff = _mm256_abs_epi16(coeff);

  const __m256i mask = _mm256_cmpgt_epi16(abs_coeff, *thr);

  const int nzflag = _mm256_movemask_epi8(mask);

  if (nzflag) {

    const __m256i tmp_rnd = _mm256_adds_epi16(abs_coeff, qp[0]);

    const __m256i abs_q = _mm256_mulhi_epi16(tmp_rnd, qp[1]);

    const __m256i q = _mm256_sign_epi16(abs_q, coeff);

    const __m256i dq = _mm256_mullo_epi16(q, qp[2]);

    const __m256i nz_mask = _mm256_cmpgt_epi16(abs_q, _mm256_setzero_si256());

    store_coefficients_avx2(q, qcoeff_ptr);

    store_coefficients_avx2(dq, dqcoeff_ptr);

    *eob = get_max_lane_eob(iscan_ptr, *eob, nz_mask);

  } else {

    write_zero(qcoeff_ptr);

    write_zero(dqcoeff_ptr);

  }

}

void av1_quantize_fp_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_ptr, const int16_t *iscan_ptr) {

  (void)scan_ptr;

  (void)zbin_ptr;

  (void)quant_shift_ptr;

  const int log_scale = 0;

  const int step = 16;

  __m256i qp[3], thr;

  __m256i eob = _mm256_setzero_si256();

  init_qp(round_ptr, quant_ptr, dequant_ptr, log_scale, &thr, qp);

  quantize_fp_16(&thr, qp, coeff_ptr, iscan_ptr, qcoeff_ptr, dqcoeff_ptr, &eob);

  coeff_ptr += step;

  qcoeff_ptr += step;

  dqcoeff_ptr += step;

  iscan_ptr += step;

  n_coeffs -= step;

  update_qp(&thr, qp);

  while (n_coeffs > 0) {

    quantize_fp_16(&thr, qp, coeff_ptr, iscan_ptr, qcoeff_ptr, dqcoeff_ptr,

                   &eob);

    coeff_ptr += step;

    qcoeff_ptr += step;

    dqcoeff_ptr += step;

    iscan_ptr += step;

    n_coeffs -= step;

  }

  *eob_ptr = quant_gather_eob(eob);

}

static AOM_FORCE_INLINE void quantize_fp_32x32(

    const __m256i *thr, const __m256i *qp, const tran_low_t *coeff_ptr,

    const int16_t *iscan_ptr, tran_low_t *qcoeff_ptr, tran_low_t *dqcoeff_ptr,

    __m256i *eob) {

  const __m256i coeff = load_coefficients_avx2(coeff_ptr);

  const __m256i abs_coeff = _mm256_abs_epi16(coeff);

  const __m256i mask = _mm256_cmpgt_epi16(abs_coeff, *thr);

  const int nzflag = _mm256_movemask_epi8(mask);

  if (nzflag) {

    const __m256i tmp_rnd = _mm256_adds_epi16(abs_coeff, qp[0]);

    const __m256i abs_q = _mm256_mulhi_epu16(tmp_rnd, qp[1]);

    const __m256i q = _mm256_sign_epi16(abs_q, coeff);

    const __m256i abs_dq =

        _mm256_srli_epi16(_mm256_mullo_epi16(abs_q, qp[2]), 1);

    const __m256i nz_mask = _mm256_cmpgt_epi16(abs_q, _mm256_setzero_si256());

    const __m256i dq = _mm256_sign_epi16(abs_dq, coeff);

    store_coefficients_avx2(q, qcoeff_ptr);

    store_coefficients_avx2(dq, dqcoeff_ptr);

    *eob = get_max_lane_eob(iscan_ptr, *eob, nz_mask);

  } else {

    write_zero(qcoeff_ptr);

    write_zero(dqcoeff_ptr);

  }

}

void av1_quantize_fp_32x32_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_ptr, const int16_t *iscan_ptr) {

  (void)scan_ptr;

  (void)zbin_ptr;

  (void)quant_shift_ptr;

  const int log_scale = 1;

  const unsigned int step = 16;

  __m256i qp[3], thr;

  __m256i eob = _mm256_setzero_si256();

  init_qp(round_ptr, quant_ptr, dequant_ptr, log_scale, &thr, qp);

  quantize_fp_32x32(&thr, qp, coeff_ptr, iscan_ptr, qcoeff_ptr, dqcoeff_ptr,

                    &eob);

  coeff_ptr += step;

  qcoeff_ptr += step;

  dqcoeff_ptr += step;

  iscan_ptr += step;

  n_coeffs -= step;

  update_qp(&thr, qp);

  while (n_coeffs > 0) {

    quantize_fp_32x32(&thr, qp, coeff_ptr, iscan_ptr, qcoeff_ptr, dqcoeff_ptr,

                      &eob);

    coeff_ptr += step;

    qcoeff_ptr += step;

    dqcoeff_ptr += step;

    iscan_ptr += step;

    n_coeffs -= step;

  }

  *eob_ptr = quant_gather_eob(eob);

}

static inline void quantize_fp_64x64(const __m256i *thr, const __m256i *qp,

                                     const tran_low_t *coeff_ptr,

                                     const int16_t *iscan_ptr,

                                     tran_low_t *qcoeff_ptr,

                                     tran_low_t *dqcoeff_ptr, __m256i *eob) {

  const __m256i coeff = load_coefficients_avx2(coeff_ptr);

  const __m256i abs_coeff = _mm256_abs_epi16(coeff);

  const __m256i mask = _mm256_cmpgt_epi16(abs_coeff, *thr);

  const int nzflag = _mm256_movemask_epi8(mask);

  if (nzflag) {

    const __m256i tmp_rnd =

        _mm256_and_si256(_mm256_adds_epi16(abs_coeff, qp[0]), mask);

    const __m256i qh = _mm256_slli_epi16(_mm256_mulhi_epi16(tmp_rnd, qp[1]), 2);

    const __m256i ql =

        _mm256_srli_epi16(_mm256_mullo_epi16(tmp_rnd, qp[1]), 14);

    const __m256i abs_q = _mm256_or_si256(qh, ql);

    const __m256i dqh = _mm256_slli_epi16(_mm256_mulhi_epi16(abs_q, qp[2]), 14);

    const __m256i dql = _mm256_srli_epi16(_mm256_mullo_epi16(abs_q, qp[2]), 2);

    const __m256i abs_dq = _mm256_or_si256(dqh, dql);

    const __m256i q = _mm256_sign_epi16(abs_q, coeff);

    const __m256i dq = _mm256_sign_epi16(abs_dq, coeff);

    // Check the signed q/dq value here instead of the absolute value. When

    // dequant equals 4, the dequant threshold (*thr) becomes 0 after being

    // scaled down by (1 + log_scale). See init_qp(). When *thr is 0 and the

    // abs_coeff is 0, the nzflag will be set. As a result, the eob will be

    // incorrectly calculated. The psign instruction corrects the error by

    // zeroing out q/dq if coeff is zero.

    const __m256i z_mask = _mm256_cmpeq_epi16(dq, _mm256_setzero_si256());

    const __m256i nz_mask = _mm256_cmpeq_epi16(z_mask, _mm256_setzero_si256());

    store_coefficients_avx2(q, qcoeff_ptr);

    store_coefficients_avx2(dq, dqcoeff_ptr);

    *eob = get_max_lane_eob(iscan_ptr, *eob, nz_mask);

  } else {

    write_zero(qcoeff_ptr);

    write_zero(dqcoeff_ptr);

  }

}

void av1_quantize_fp_64x64_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_ptr, const int16_t *iscan_ptr) {

  (void)scan_ptr;

  (void)zbin_ptr;

  (void)quant_shift_ptr;

  const int log_scale = 2;

  const unsigned int step = 16;

  __m256i qp[3], thr;

  __m256i eob = _mm256_setzero_si256();

  init_qp(round_ptr, quant_ptr, dequant_ptr, log_scale, &thr, qp);

  quantize_fp_64x64(&thr, qp, coeff_ptr, iscan_ptr, qcoeff_ptr, dqcoeff_ptr,

                    &eob);

  coeff_ptr += step;

  qcoeff_ptr += step;

  dqcoeff_ptr += step;

  iscan_ptr += step;

  n_coeffs -= step;

  update_qp(&thr, qp);

  while (n_coeffs > 0) {

    quantize_fp_64x64(&thr, qp, coeff_ptr, iscan_ptr, qcoeff_ptr, dqcoeff_ptr,

                      &eob);

    coeff_ptr += step;

    qcoeff_ptr += step;

    dqcoeff_ptr += step;

    iscan_ptr += step;

    n_coeffs -= step;

  }

  *eob_ptr = quant_gather_eob(eob);

}