/*****************************************************************************
* This file is part of Kvazaar HEVC encoder.
*
* Copyright (C) 2013-2015 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 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.
*
* 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 Lesser General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with Kvazaar. If not, see .
****************************************************************************/
#include "strategyselector.h"
#include "avx2_common_functions.h"
#include "cabac.h"
#include "context.h"
#include "encode_coding_tree-avx2.h"
#include "kvz_math.h"
#include
// GCC headers apparently won't have this at all.. sigh
#ifndef _andn_u32
#define _andn_u32(x, y) (__andn_u32((x), (y)))
#endif
/*
* NOTE: Returns 10, not 11 like SSE and AVX comparisons do, as the bit pattern
* implying greaterness
*/
static INLINE uint32_t _mm32_cmpgt_epu2(uint32_t a, uint32_t b)
{
const uint32_t himask = 0xaaaaaaaa;
uint32_t a_gt_b = _andn_u32(b, a);
uint32_t a_ne_b = a ^ b;
uint32_t a_gt_b_sh = a_gt_b << 1;
uint32_t lobit_tiebrk_hi = _andn_u32(a_ne_b, a_gt_b_sh);
uint32_t res = (a_gt_b | lobit_tiebrk_hi) & himask;
return res;
}
static INLINE uint32_t pack_16x16b_to_16x2b(__m256i src)
{
/*
* For each 16-bit element in src:
* ABCD EFGH IJKL MNOP Original elements
* 0000 0000 0000 00XY Element clipped to [0, 3] using _mm256_min_epu16
* 0000 000X Y000 0000 Shift word to align LSBs across byte boundary
* 0000 0001 1000 0000 Comparison mask to be compared against
* XXXX XXXX YYYY YYYY Comparison result, for movemask
*/
const __m256i threes = _mm256_set1_epi16 (3);
const __m256i cmpmask = _mm256_set1_epi16 (0x0180);
__m256i clipped = _mm256_min_epu16 (src, threes);
__m256i shifted = _mm256_slli_epi16 (clipped, 7);
__m256i cmpres = _mm256_cmpeq_epi8 (shifted, cmpmask);
uint32_t result = _mm256_movemask_epi8(cmpres);
return result;
}
/**
* \brief Context derivation process of coeff_abs_significant_flag,
* parallelized to handle 16 coeffs at once
* \param pattern_sig_ctx pattern for current coefficient group
* \param scan_idx pixel scan type in use
* \param pos_xs column addresses of current scan positions
* \param pos_ys row addresses of current scan positions
* \param block_type log2 value of block size if square block, or 4 otherwise
* \param width width of the block
* \param texture_type texture type (TEXT_LUMA...)
* \returns ctx_inc for current scan position
*/
static INLINE __m256i kvz_context_get_sig_ctx_inc_16x16b(int32_t pattern_sig_ctx, uint32_t scan_idx, __m256i pos_xs,
__m256i pos_ys, int32_t block_type, int8_t texture_type)
{
const __m256i zero = _mm256_set1_epi8(0);
const __m256i ff = _mm256_set1_epi8(0xff);
const __m256i ones = _mm256_set1_epi16(1);
const __m256i twos = _mm256_set1_epi16(2);
const __m256i threes = _mm256_set1_epi16(3);
const __m256i ctx_ind_map[3] = {
_mm256_setr_epi16(
0, 2, 1, 6,
3, 4, 7, 6,
4, 5, 7, 8,
5, 8, 8, 8
),
_mm256_setr_epi16(
0, 1, 4, 5,
2, 3, 4, 5,
6, 6, 8, 8,
7, 7, 8, 8
),
_mm256_setr_epi16(
0, 2, 6, 7,
1, 3, 6, 7,
4, 4, 8, 8,
5, 5, 8, 8
),
};
int16_t offset;
if (block_type == 3)
if (scan_idx == SCAN_DIAG)
offset = 9;
else
offset = 15;
else
if (texture_type == 0)
offset = 21;
else
offset = 12;
__m256i offsets = _mm256_set1_epi16(offset);
// This will only ever be compared to 0, 1 and 2, so it's fine to cast down
// to 16b (and it should never be above 3 anyways)
__m256i pattern_sig_ctxs = _mm256_set1_epi16((int16_t)(MIN(0xffff, pattern_sig_ctx)));
__m256i pattern_sig_ctxs_eq_zero = _mm256_cmpeq_epi16(pattern_sig_ctxs, zero);
__m256i pattern_sig_ctxs_eq_one = _mm256_cmpeq_epi16(pattern_sig_ctxs, ones);
__m256i pattern_sig_ctxs_eq_two = _mm256_cmpeq_epi16(pattern_sig_ctxs, twos);
__m256i pattern_sig_ctxs_eq_1or2 = _mm256_or_si256 (pattern_sig_ctxs_eq_one,
pattern_sig_ctxs_eq_two);
__m256i pattern_sig_ctxs_lt3 = _mm256_or_si256 (pattern_sig_ctxs_eq_1or2,
pattern_sig_ctxs_eq_zero);
__m256i pattern_sig_ctxs_other = _mm256_xor_si256(pattern_sig_ctxs_lt3,
ff);
__m256i x_plus_y = _mm256_add_epi16 (pos_xs, pos_ys);
__m256i x_plus_y_zero = _mm256_cmpeq_epi16(x_plus_y, zero); // All these should be 0, preempts block_type_two rule
__m256i texture_types = _mm256_set1_epi16((int16_t)texture_type);
__m256i block_types = _mm256_set1_epi16((int16_t)block_type);
__m256i block_type_two = _mm256_cmpeq_epi16(block_types, twos); // All these should be ctx_ind_map[4 * pos_y + pos_x];
__m256i bt2_vals = ctx_ind_map[scan_idx];
__m256i bt2_vals_masked = _mm256_and_si256(bt2_vals, block_type_two);
__m256i pos_xs_in_subset = _mm256_and_si256(pos_xs, threes);
__m256i pos_ys_in_subset = _mm256_and_si256(pos_ys, threes);
__m256i cg_pos_xs = _mm256_srli_epi16(pos_xs, 2);
__m256i cg_pos_ys = _mm256_srli_epi16(pos_ys, 2);
__m256i cg_pos_xysums = _mm256_add_epi16 (cg_pos_xs, cg_pos_ys);
__m256i pos_xy_sums_in_subset = _mm256_add_epi16(pos_xs_in_subset, pos_ys_in_subset);
/*
* if (pattern_sig_ctx == 0) {
* switch (pos_x_in_subset + pos_y_in_subset) {
* case 0:
* cnt = 2;
* break;
* case 1:
* case 2:
* cnt = 1;
* break;
* default:
* cnt = 0;
* }
* }
*
* Equivalent to:
*
* if (pattern_sig_ctx == 0) {
* subamt = cnt <= 1 ? 1 : 0;
* pxyis_max3 = min(3, pos_x_in_subset + pos_y_in_subset);
* cnt = (3 - pxyis_max3) - subamt;
* }
*/
__m256i pxyis_lte_1 = _mm256_cmpgt_epi16(twos, pos_xy_sums_in_subset);
__m256i subamts = _mm256_and_si256 (pxyis_lte_1, ones);
__m256i pxyis_max3 = _mm256_min_epu16 (pos_xy_sums_in_subset, threes);
__m256i cnts_tmp = _mm256_sub_epi16 (threes, pxyis_max3);
__m256i cnts_sig_ctx_0 = _mm256_sub_epi16 (cnts_tmp, subamts);
__m256i cnts_sc0_masked = _mm256_and_si256 (cnts_sig_ctx_0, pattern_sig_ctxs_eq_zero);
/*
* if (pattern_sig_ctx == 1 || pattern_sig_ctx == 2) {
* if (pattern_sig_ctx == 1)
* subtrahend = pos_y_in_subset;
* else
* subtrahend = pos_x_in_subset;
* cnt = 2 - min(2, subtrahend);
* }
*/
__m256i pos_operands_ctx_1or2 = _mm256_blendv_epi8(pos_ys_in_subset,
pos_xs_in_subset,
pattern_sig_ctxs_eq_two);
__m256i pos_operands_max2 = _mm256_min_epu16 (pos_operands_ctx_1or2, twos);
__m256i cnts_sig_ctx_1or2 = _mm256_sub_epi16 (twos, pos_operands_max2);
__m256i cnts_sc12_masked = _mm256_and_si256 (cnts_sig_ctx_1or2, pattern_sig_ctxs_eq_1or2);
/*
* if (pattern_sig_ctx > 2)
* cnt = 2;
*/
__m256i cnts_scother_masked = _mm256_and_si256(twos, pattern_sig_ctxs_other);
// Select correct count
__m256i cnts_sc012_masked = _mm256_or_si256 (cnts_sc0_masked, cnts_sc12_masked);
__m256i cnts = _mm256_or_si256 (cnts_scother_masked, cnts_sc012_masked);
// Compute final values
__m256i textype_eq_0 = _mm256_cmpeq_epi16(texture_types, zero);
__m256i cg_pos_sums_gt_0 = _mm256_cmpgt_epi16(cg_pos_xysums, zero);
__m256i tmpcond = _mm256_and_si256 (textype_eq_0, cg_pos_sums_gt_0);
__m256i tmp = _mm256_and_si256 (tmpcond, threes);
__m256i tmp_with_offsets = _mm256_add_epi16 (tmp, offsets);
__m256i rv_noshortcirc = _mm256_add_epi16 (cnts, tmp_with_offsets);
// Ol' sprite mask method works here!
__m256i rv1 = _mm256_andnot_si256(block_type_two, rv_noshortcirc);
__m256i rv2 = _mm256_or_si256 (rv1, bt2_vals_masked);
__m256i rv = _mm256_andnot_si256(x_plus_y_zero, rv2);
return rv;
}
/**
* \brief Encode (X,Y) position of the last significant coefficient
*
* \param lastpos_x X component of last coefficient
* \param lastpos_y Y component of last coefficient
* \param width Block width
* \param height Block height
* \param type plane type / luminance or chrominance
* \param scan scan type (diag, hor, ver)
*
* This method encodes the X and Y component within a block of the last
* significant coefficient.
*/
static void encode_last_significant_xy(cabac_data_t * const cabac,
uint8_t lastpos_x, uint8_t lastpos_y,
uint8_t width, uint8_t height,
uint8_t type, uint8_t scan)
{
const int index = kvz_math_floor_log2(width) - 2;
uint8_t ctx_offset = type ? 0 : (index * 3 + (index + 1) / 4);
uint8_t shift = type ? index : (index + 3) / 4;
cabac_ctx_t *base_ctx_x = (type ? cabac->ctx.cu_ctx_last_x_chroma : cabac->ctx.cu_ctx_last_x_luma);
cabac_ctx_t *base_ctx_y = (type ? cabac->ctx.cu_ctx_last_y_chroma : cabac->ctx.cu_ctx_last_y_luma);
if (scan == SCAN_VER) {
SWAP(lastpos_x, lastpos_y, uint8_t);
}
const int group_idx_x = g_group_idx[lastpos_x];
const int group_idx_y = g_group_idx[lastpos_y];
// x prefix
for (int last_x = 0; last_x < group_idx_x; last_x++) {
cabac->cur_ctx = &base_ctx_x[ctx_offset + (last_x >> shift)];
CABAC_BIN(cabac, 1, "last_sig_coeff_x_prefix");
}
if (group_idx_x < g_group_idx[width - 1]) {
cabac->cur_ctx = &base_ctx_x[ctx_offset + (group_idx_x >> shift)];
CABAC_BIN(cabac, 0, "last_sig_coeff_x_prefix");
}
// y prefix
for (int last_y = 0; last_y < group_idx_y; last_y++) {
cabac->cur_ctx = &base_ctx_y[ctx_offset + (last_y >> shift)];
CABAC_BIN(cabac, 1, "last_sig_coeff_y_prefix");
}
if (group_idx_y < g_group_idx[height - 1]) {
cabac->cur_ctx = &base_ctx_y[ctx_offset + (group_idx_y >> shift)];
CABAC_BIN(cabac, 0, "last_sig_coeff_y_prefix");
}
// last_sig_coeff_x_suffix
if (group_idx_x > 3) {
const int suffix = lastpos_x - g_min_in_group[group_idx_x];
const int bits = (group_idx_x - 2) / 2;
CABAC_BINS_EP(cabac, suffix, bits, "last_sig_coeff_x_suffix");
}
// last_sig_coeff_y_suffix
if (group_idx_y > 3) {
const int suffix = lastpos_y - g_min_in_group[group_idx_y];
const int bits = (group_idx_y - 2) / 2;
CABAC_BINS_EP(cabac, suffix, bits, "last_sig_coeff_y_suffix");
}
}
void kvz_encode_coeff_nxn_avx2(encoder_state_t * const state,
cabac_data_t * const cabac,
const coeff_t *coeff,
uint8_t width,
uint8_t type,
int8_t scan_mode,
int8_t tr_skip)
{
const encoder_control_t * const encoder = state->encoder_control;
int c1 = 1;
uint8_t last_coeff_x = 0;
uint8_t last_coeff_y = 0;
int32_t i;
uint32_t sig_coeffgroup_flag[8 * 8] = { 0 };
int8_t be_valid = encoder->cfg.signhide_enable;
int32_t scan_pos_sig;
uint32_t go_rice_param = 0;
uint32_t ctx_sig;
// CONSTANTS
const uint32_t num_blk_side = width >> TR_MIN_LOG2_SIZE;
const uint32_t log2_block_size = kvz_g_convert_to_bit[width] + 2;
const uint32_t *scan =
kvz_g_sig_last_scan[scan_mode][log2_block_size - 1];
const uint32_t *scan_cg = g_sig_last_scan_cg[log2_block_size - 2][scan_mode];
const uint32_t num_blocks = num_blk_side * num_blk_side;
const __m256i zero = _mm256_set1_epi8(0);
const __m256i ones = _mm256_set1_epi16(1);
const __m256i twos = _mm256_set1_epi16(2);
// Init base contexts according to block type
cabac_ctx_t *base_coeff_group_ctx = &(cabac->ctx.cu_sig_coeff_group_model[type]);
cabac_ctx_t *baseCtx = (type == 0) ? &(cabac->ctx.cu_sig_model_luma[0]) :
&(cabac->ctx.cu_sig_model_chroma[0]);
// Scan all coeff groups to find out which of them have coeffs.
// Populate sig_coeffgroup_flag with that info.
// NOTE: Modified the functionality a bit, sig_coeffgroup_flag used to be
// 1 if true and 0 if false, now it's "undefined but nonzero" if true and
// 0 if false (not actually undefined, it's a bitmask representing the
// significant coefficients' position in the group which in itself could
// be useful information)
int32_t scan_cg_last = -1;
for (int32_t i = 0; i < num_blocks; i++) {
const uint32_t cg_id = scan_cg[i];
const uint32_t n_xbits = log2_block_size - 2; // How many lowest bits of scan_cg represent X coord
const uint32_t cg_x = cg_id & ((1 << n_xbits) - 1);
const uint32_t cg_y = cg_id >> n_xbits;
const uint32_t cg_pos = cg_y * width * 4 + cg_x * 4;
const uint32_t cg_pos_y = (cg_pos >> log2_block_size) >> TR_MIN_LOG2_SIZE;
const uint32_t cg_pos_x = (cg_pos & (width - 1)) >> TR_MIN_LOG2_SIZE;
const uint32_t addr = cg_pos_x + cg_pos_y * num_blk_side;
__m128d coeffs_d_upper = _mm_setzero_pd();
__m128d coeffs_d_lower = _mm_setzero_pd();
__m128i coeffs_upper;
__m128i coeffs_lower;
__m256i cur_coeffs;
coeffs_d_upper = _mm_loadl_pd(coeffs_d_upper, (double *)(coeff + cg_pos + 0 * width));
coeffs_d_upper = _mm_loadh_pd(coeffs_d_upper, (double *)(coeff + cg_pos + 1 * width));
coeffs_d_lower = _mm_loadl_pd(coeffs_d_lower, (double *)(coeff + cg_pos + 2 * width));
coeffs_d_lower = _mm_loadh_pd(coeffs_d_lower, (double *)(coeff + cg_pos + 3 * width));
coeffs_upper = _mm_castpd_si128(coeffs_d_upper);
coeffs_lower = _mm_castpd_si128(coeffs_d_lower);
cur_coeffs = _mm256_insertf128_si256(_mm256_castsi128_si256(coeffs_upper),
coeffs_lower,
1);
__m256i coeffs_zero = _mm256_cmpeq_epi16(cur_coeffs, zero);
uint32_t nz_coeffs_2b = ~((uint32_t)_mm256_movemask_epi8(coeffs_zero));
sig_coeffgroup_flag[addr] = nz_coeffs_2b;
if (nz_coeffs_2b)
scan_cg_last = i;
}
// Rest of the code assumes at least one non-zero coeff.
assert(scan_cg_last >= 0);
ALIGNED(64) int16_t coeff_reord[LCU_WIDTH * LCU_WIDTH];
uint32_t pos_last, scan_pos_last;
{
__m256i coeffs_r;
for (int32_t i = 0; i <= scan_cg_last; i++) {
int32_t subpos = i * 16;
scanord_read_vector(&coeff, scan, scan_mode, subpos, width, &coeffs_r, 1);
_mm256_store_si256((__m256i *)(coeff_reord + subpos), coeffs_r);
}
// Find the last coeff by going backwards in scan order.
uint32_t baseaddr = scan_cg_last * 16;
__m256i cur_coeffs_zeros = _mm256_cmpeq_epi16(coeffs_r, zero);
uint32_t nz_bytes = ~(_mm256_movemask_epi8(cur_coeffs_zeros));
scan_pos_last = baseaddr + ((31 - _lzcnt_u32(nz_bytes)) >> 1);
pos_last = scan[scan_pos_last];
}
// transform skip flag
if(width == 4 && encoder->cfg.trskip_enable) {
cabac->cur_ctx = (type == 0) ? &(cabac->ctx.transform_skip_model_luma) : &(cabac->ctx.transform_skip_model_chroma);
CABAC_BIN(cabac, tr_skip, "transform_skip_flag");
}
last_coeff_x = pos_last & (width - 1);
last_coeff_y = (uint8_t)(pos_last >> log2_block_size);
// Code last_coeff_x and last_coeff_y
encode_last_significant_xy(cabac,
last_coeff_x,
last_coeff_y,
width,
width,
type,
scan_mode);
scan_pos_sig = scan_pos_last;
ALIGNED(64) uint16_t abs_coeff[16];
ALIGNED(32) uint16_t abs_coeff_buf_sb[16];
ALIGNED(32) int16_t pos_ys_buf[16];
ALIGNED(32) int16_t pos_xs_buf[16];
ALIGNED(32) int16_t ctx_sig_buf[16];
abs_coeff[0] = abs(coeff[pos_last]);
uint32_t coeff_signs = (coeff[pos_last] < 0);
int32_t num_non_zero = 1;
int32_t last_nz_pos_in_cg = scan_pos_sig;
int32_t first_nz_pos_in_cg = scan_pos_sig;
scan_pos_sig--;
// significant_coeff_flag
for (i = scan_cg_last; i >= 0; i--) {
int32_t sub_pos = i << 4; // LOG2_SCAN_SET_SIZE;
int32_t cg_blk_pos = scan_cg[i];
int32_t cg_pos_y = cg_blk_pos / num_blk_side;
int32_t cg_pos_x = cg_blk_pos - (cg_pos_y * num_blk_side);
go_rice_param = 0;
if (i == scan_cg_last || i == 0) {
sig_coeffgroup_flag[cg_blk_pos] = 1;
} else {
uint32_t sig_coeff_group = (sig_coeffgroup_flag[cg_blk_pos] != 0);
uint32_t ctx_sig = kvz_context_get_sig_coeff_group(sig_coeffgroup_flag, cg_pos_x,
cg_pos_y, width);
cabac->cur_ctx = &base_coeff_group_ctx[ctx_sig];
CABAC_BIN(cabac, sig_coeff_group, "coded_sub_block_flag");
}
if (sig_coeffgroup_flag[cg_blk_pos]) {
int32_t pattern_sig_ctx = kvz_context_calc_pattern_sig_ctx(sig_coeffgroup_flag,
cg_pos_x, cg_pos_y, width);
const __m256i coeff_pos_zero = _mm256_castsi128_si256(_mm_cvtsi32_si128(0xffff));
const __m128i log2_block_size_128 = _mm_cvtsi32_si128(log2_block_size);
__m256i coeffs = _mm256_load_si256((__m256i *)(coeff_reord + sub_pos));
__m256i sigs_inv = _mm256_cmpeq_epi16(coeffs, zero);
__m256i is = _mm256_set1_epi16(i);
__m256i is_zero = _mm256_cmpeq_epi16(is, zero);
__m256i coeffs_subzero = _mm256_cmpgt_epi16(zero, coeffs);
__m256i masked_coeffs = _mm256_andnot_si256(sigs_inv, coeffs);
__m256i abs_coeffs = _mm256_abs_epi16(masked_coeffs);
// TODO: obtain 16-bit block positions, maybe? :P
__m256i blk_poses_hi = _mm256_loadu_si256((__m256i *)(scan + sub_pos + 8));
__m256i blk_poses_lo = _mm256_loadu_si256((__m256i *)(scan + sub_pos + 0));
__m256i blk_poses_tmp = _mm256_packs_epi32(blk_poses_lo, blk_poses_hi);
__m256i blk_poses = _mm256_permute4x64_epi64(blk_poses_tmp, _MM_SHUFFLE(3, 1, 2, 0));
__m256i pos_ys = _mm256_srl_epi16(blk_poses, log2_block_size_128);
__m256i pos_xs = _mm256_sub_epi16(blk_poses, _mm256_sll_epi16(pos_ys, log2_block_size_128));
_mm256_store_si256((__m256i *)pos_ys_buf, pos_ys);
_mm256_store_si256((__m256i *)pos_xs_buf, pos_xs);
__m256i encode_sig_coeff_flags_inv = _mm256_andnot_si256(is_zero, coeff_pos_zero);
get_first_last_nz_int16(masked_coeffs, &first_nz_pos_in_cg, &last_nz_pos_in_cg);
_mm256_store_si256((__m256i *)abs_coeff_buf_sb, abs_coeffs);
__m256i ctx_sigs = kvz_context_get_sig_ctx_inc_16x16b(pattern_sig_ctx, scan_mode, pos_xs, pos_ys,
log2_block_size, type);
_mm256_store_si256((__m256i *)ctx_sig_buf, ctx_sigs);
uint32_t esc_flags = ~(_mm256_movemask_epi8(encode_sig_coeff_flags_inv));
uint32_t sigs = ~(_mm256_movemask_epi8(sigs_inv));
uint32_t coeff_sign_buf = _mm256_movemask_epi8(coeffs_subzero);
for (; scan_pos_sig >= sub_pos; scan_pos_sig--) {
uint32_t id = scan_pos_sig - sub_pos;
uint32_t shamt = (id << 1) + 1;
uint32_t curr_sig = (sigs >> shamt) & 1;
uint32_t curr_esc_flag = (esc_flags >> shamt) & 1;
uint32_t curr_coeff_sign = (coeff_sign_buf >> shamt) & 1;
if (curr_esc_flag | num_non_zero) {
ctx_sig = ctx_sig_buf[id];
cabac->cur_ctx = &baseCtx[ctx_sig];
CABAC_BIN(cabac, curr_sig, "sig_coeff_flag");
}
if (curr_sig) {
abs_coeff[num_non_zero] = abs_coeff_buf_sb[id];
coeff_signs = 2 * coeff_signs + curr_coeff_sign;
num_non_zero++;
}
}
} else {
scan_pos_sig = sub_pos - 1;
}
if (num_non_zero > 0) {
bool sign_hidden = last_nz_pos_in_cg - first_nz_pos_in_cg >= 4 /* SBH_THRESHOLD */
&& !encoder->cfg.lossless;
uint32_t ctx_set = (i > 0 && type == 0) ? 2 : 0;
cabac_ctx_t *base_ctx_mod;
int32_t num_c1_flag, first_c2_flag_idx, idx;
__m256i abs_coeffs = _mm256_load_si256((__m256i *)abs_coeff);
__m256i coeffs_gt1 = _mm256_cmpgt_epi16(abs_coeffs, ones);
__m256i coeffs_gt2 = _mm256_cmpgt_epi16(abs_coeffs, twos);
uint32_t coeffs_gt1_bits = _mm256_movemask_epi8(coeffs_gt1);
uint32_t coeffs_gt2_bits = _mm256_movemask_epi8(coeffs_gt2);
if (c1 == 0) {
ctx_set++;
}
base_ctx_mod = (type == 0) ? &(cabac->ctx.cu_one_model_luma[4 * ctx_set]) :
&(cabac->ctx.cu_one_model_chroma[4 * ctx_set]);
num_c1_flag = MIN(num_non_zero, C1FLAG_NUMBER);
first_c2_flag_idx = -1;
/*
* c1s_pattern is 16 base-4 numbers: 3, 3, 3, ... , 3, 2 (c1 will never
* be less than 0 or greater than 3, so two bits per iter are enough).
* It's essentially the values that c1 will be for the next iteration as
* long as we have not encountered any >1 symbols. Count how long run of
* such symbols there is in the beginning of this CG, and zero all c1's
* that are located at or after the first >1 symbol.
*/
const uint32_t c1s_pattern = 0xfffffffe;
uint32_t n_nongt1_bits = _tzcnt_u32(coeffs_gt1_bits);
uint32_t c1s_nextiter = _bzhi_u32(c1s_pattern, n_nongt1_bits);
first_c2_flag_idx = n_nongt1_bits >> 1;
c1 = 1;
for (idx = 0; idx < num_c1_flag; idx++) {
uint32_t shamt = idx << 1;
uint32_t symbol = (coeffs_gt1_bits >> shamt) & 1;
cabac->cur_ctx = &base_ctx_mod[c1];
CABAC_BIN(cabac, symbol, "coeff_abs_level_greater1_flag");
c1 = (c1s_nextiter >> shamt) & 3;
}
if (c1 == 0) {
base_ctx_mod = (type == 0) ? &(cabac->ctx.cu_abs_model_luma[ctx_set]) :
&(cabac->ctx.cu_abs_model_chroma[ctx_set]);
if (first_c2_flag_idx != -1) {
uint32_t shamt = (first_c2_flag_idx << 1) + 1;
uint8_t symbol = (coeffs_gt2_bits >> shamt) & 1;
cabac->cur_ctx = &base_ctx_mod[0];
CABAC_BIN(cabac, symbol, "coeff_abs_level_greater2_flag");
}
}
int32_t shiftamt = (be_valid && sign_hidden) ? 1 : 0;
int32_t nnz = num_non_zero - shiftamt;
coeff_signs >>= shiftamt;
if (!cabac->only_count) {
if (encoder->cfg.crypto_features & KVZ_CRYPTO_TRANSF_COEFF_SIGNS) {
coeff_signs ^= kvz_crypto_get_key(state->crypto_hdl, nnz);
}
}
CABAC_BINS_EP(cabac, coeff_signs, nnz, "coeff_sign_flag");
if (c1 == 0 || num_non_zero > C1FLAG_NUMBER) {
const __m256i ones = _mm256_set1_epi16(1);
__m256i abs_coeffs_gt1 = _mm256_cmpgt_epi16 (abs_coeffs, ones);
uint32_t acgt1_bits = _mm256_movemask_epi8(abs_coeffs_gt1);
uint32_t first_acgt1_bpos = _tzcnt_u32(acgt1_bits);
uint32_t abs_coeffs_base4 = pack_16x16b_to_16x2b(abs_coeffs);
const uint32_t ones_base4 = 0x55555555;
const uint32_t twos_base4 = 0xaaaaaaaa;
const uint32_t c1flag_number_mask_inv = 0xffffffff << (C1FLAG_NUMBER << 1);
const uint32_t c1flag_number_mask = ~c1flag_number_mask_inv;
// The addition will not overflow between 2-bit atoms because
// first_coeff2s will only be 1 or 0, and the other addend is 2
uint32_t first_coeff2s = _bzhi_u32(ones_base4, first_acgt1_bpos + 2);
uint32_t base_levels = first_coeff2s + twos_base4;
base_levels &= c1flag_number_mask;
base_levels |= (ones_base4 & c1flag_number_mask_inv);
uint32_t encode_decisions = _mm32_cmpgt_epu2(base_levels, abs_coeffs_base4);
for (idx = 0; idx < num_non_zero; idx++) {
uint32_t shamt = idx << 1;
uint32_t dont_encode_curr = (encode_decisions >> shamt) & 3;
int16_t base_level = (base_levels >> shamt) & 3;
uint16_t curr_abs_coeff = abs_coeff[idx];
if (!dont_encode_curr) {
uint16_t level_diff = curr_abs_coeff - base_level;
if (!cabac->only_count && (encoder->cfg.crypto_features & KVZ_CRYPTO_TRANSF_COEFFS)) {
kvz_cabac_write_coeff_remain_encry(state, cabac, level_diff, go_rice_param, base_level);
} else {
kvz_cabac_write_coeff_remain(cabac, level_diff, go_rice_param);
}
if (curr_abs_coeff > 3 * (1 << go_rice_param)) {
go_rice_param = MIN(go_rice_param + 1, 4);
}
}
}
}
}
last_nz_pos_in_cg = -1;
first_nz_pos_in_cg = 16;
num_non_zero = 0;
coeff_signs = 0;
}
}
int kvz_strategy_register_encode_avx2(void* opaque, uint8_t bitdepth)
{
bool success = true;
success &= kvz_strategyselector_register(opaque, "encode_coeff_nxn", "avx2", 40, &kvz_encode_coeff_nxn_avx2);
return success;
}