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| -rw-r--r-- | src/liblzma/lzma/lzma_encoder_getoptimum.c | 893 |
1 files changed, 893 insertions, 0 deletions
diff --git a/src/liblzma/lzma/lzma_encoder_getoptimum.c b/src/liblzma/lzma/lzma_encoder_getoptimum.c new file mode 100644 index 00000000..cdeb3145 --- /dev/null +++ b/src/liblzma/lzma/lzma_encoder_getoptimum.c @@ -0,0 +1,893 @@ +/////////////////////////////////////////////////////////////////////////////// +// +/// \file lzma_encoder_getoptimum.c +// +// Copyright (C) 1999-2006 Igor Pavlov +// Copyright (C) 2007 Lasse Collin +// +// This library 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. +// +// This library 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. +// +/////////////////////////////////////////////////////////////////////////////// + +// NOTE: If you want to keep the line length in 80 characters, set +// tab width to 4 or less in your editor when editing this file. + + +// "Would you love the monster code? +// Could you understand beauty of the beast?" +// --Adapted from Lordi's "Would you love a monster man". + + +#include "lzma_encoder_private.h" + + +#define length_get_price(length_encoder, symbol, pos_state) \ + (length_encoder).prices[pos_state][symbol] + + +#define get_rep_len_1_price(state, pos_state) \ + bit_get_price_0(coder->is_rep0[state]) \ + + bit_get_price_0(coder->is_rep0_long[state][pos_state]) + + +// Adds to price_target. +#define get_pure_rep_price(price_target, rep_index, state, pos_state) \ +do { \ + if ((rep_index) == 0) { \ + price_target += bit_get_price_0(coder->is_rep0[state]); \ + price_target += bit_get_price_1( \ + coder->is_rep0_long[state][pos_state]); \ + } else { \ + price_target += bit_get_price_1(coder->is_rep0[state]); \ + if ((rep_index) == 1) { \ + price_target += bit_get_price_0(coder->is_rep1[state]); \ + } else { \ + price_target += bit_get_price_1(coder->is_rep1[state]); \ + price_target += bit_get_price( \ + coder->is_rep2[state], (rep_index) - 2); \ + } \ + } \ +} while (0) + + +// Adds to price_target. +#define get_rep_price(price_target, rep_index, len, state, pos_state) \ +do { \ + get_pure_rep_price(price_target, rep_index, state, pos_state); \ + price_target += length_get_price(coder->rep_match_len_encoder, \ + (len) - MATCH_MIN_LEN, pos_state); \ +} while (0) + + +// Adds to price_target. +#define get_pos_len_price(price_target, pos, len, pos_state) \ +do { \ + const uint32_t len_to_pos_state_tmp = get_len_to_pos_state(len); \ + if ((pos) < FULL_DISTANCES) { \ + price_target += distances_prices[len_to_pos_state_tmp][pos]; \ + } else { \ + price_target \ + += pos_slot_prices[len_to_pos_state_tmp][get_pos_slot_2(pos)] \ + + align_prices[(pos) & ALIGN_MASK]; \ + } \ + price_target += length_get_price( \ + coder->len_encoder, (len) - MATCH_MIN_LEN, pos_state); \ +} while (0) + + +// Three macros to manipulate lzma_optimal structures: +#define make_as_char(opt) \ +do { \ + (opt).back_prev = UINT32_MAX; \ + (opt).prev_1_is_char = false; \ +} while (0) + + +#define make_as_short_rep(opt) \ +do { \ + (opt).back_prev = 0; \ + (opt).prev_1_is_char = false; \ +} while (0) + + +#define is_short_rep(opt) \ + ((opt).back_prev == 0) + + +static void +fill_distances_prices(lzma_coder *coder) +{ + uint32_t temp_prices[FULL_DISTANCES]; + + for (uint32_t i = START_POS_MODEL_INDEX; i < FULL_DISTANCES; ++i) { + const uint32_t pos_slot = get_pos_slot(i); + const uint32_t footer_bits = ((pos_slot >> 1) - 1); + const uint32_t base = (2 | (pos_slot & 1)) << footer_bits; + temp_prices[i] = 0; + bittree_reverse_get_price(temp_prices[i], + coder->pos_encoders + base - pos_slot - 1, + footer_bits, i - base); + } + + const uint32_t dist_table_size = coder->dist_table_size; + + for (uint32_t len_to_pos_state = 0; + len_to_pos_state < LEN_TO_POS_STATES; + ++len_to_pos_state) { + + const probability *encoder = coder->pos_slot_encoder[len_to_pos_state]; + uint32_t *pos_slot_prices = coder->pos_slot_prices[len_to_pos_state]; + + for (uint32_t pos_slot = 0; + pos_slot < dist_table_size; + ++pos_slot) { + pos_slot_prices[pos_slot] = 0; + bittree_get_price(pos_slot_prices[pos_slot], encoder, + POS_SLOT_BITS, pos_slot); + } + + for (uint32_t pos_slot = END_POS_MODEL_INDEX; + pos_slot < dist_table_size; + ++pos_slot) + pos_slot_prices[pos_slot] += (((pos_slot >> 1) - 1) + - ALIGN_BITS) << BIT_PRICE_SHIFT_BITS; + + + uint32_t *distances_prices + = coder->distances_prices[len_to_pos_state]; + + uint32_t i; + for (i = 0; i < START_POS_MODEL_INDEX; ++i) + distances_prices[i] = pos_slot_prices[i]; + + for (; i < FULL_DISTANCES; ++i) + distances_prices[i] = pos_slot_prices[get_pos_slot(i)] + + temp_prices[i]; + } + + coder->match_price_count = 0; + + return; +} + + +static void +fill_align_prices(lzma_coder *coder) +{ + for (uint32_t i = 0; i < ALIGN_TABLE_SIZE; ++i) { + uint32_t tmp = 0; + bittree_reverse_get_price(tmp, coder->pos_align_encoder, + ALIGN_BITS, i); + coder->align_prices[i] = tmp; + } + + coder->align_price_count = 0; +} + + +// The first argument is a pointer returned by literal_get_subcoder(). +static uint32_t +literal_get_price(const probability *encoders, const bool match_mode, + const uint8_t match_byte, const uint8_t symbol) +{ + uint32_t price = 0; + uint32_t context = 1; + int i = 8; + + if (match_mode) { + do { + --i; + const uint32_t match_bit = (match_byte >> i) & 1; + const uint32_t bit = (symbol >> i) & 1; + const uint32_t subcoder_index + = 0x100 + (match_bit << 8) + context; + + price += bit_get_price(encoders[subcoder_index], bit); + context = (context << 1) | bit; + + if (match_bit != bit) + break; + + } while (i != 0); + } + + while (i != 0) { + --i; + const uint32_t bit = (symbol >> i) & 1; + price += bit_get_price(encoders[context], bit); + context = (context << 1) | bit; + } + + return price; +} + + +static void +backward(lzma_coder *restrict coder, uint32_t *restrict len_res, + uint32_t *restrict back_res, uint32_t cur) +{ + coder->optimum_end_index = cur; + + uint32_t pos_mem = coder->optimum[cur].pos_prev; + uint32_t back_mem = coder->optimum[cur].back_prev; + + do { + if (coder->optimum[cur].prev_1_is_char) { + make_as_char(coder->optimum[pos_mem]); + coder->optimum[pos_mem].pos_prev = pos_mem - 1; + + if (coder->optimum[cur].prev_2) { + coder->optimum[pos_mem - 1].prev_1_is_char = false; + coder->optimum[pos_mem - 1].pos_prev + = coder->optimum[cur].pos_prev_2; + coder->optimum[pos_mem - 1].back_prev + = coder->optimum[cur].back_prev_2; + } + } + + uint32_t pos_prev = pos_mem; + uint32_t back_cur = back_mem; + + back_mem = coder->optimum[pos_prev].back_prev; + pos_mem = coder->optimum[pos_prev].pos_prev; + + coder->optimum[pos_prev].back_prev = back_cur; + coder->optimum[pos_prev].pos_prev = cur; + cur = pos_prev; + + } while (cur != 0); + + coder->optimum_current_index = coder->optimum[0].pos_prev; + *len_res = coder->optimum[0].pos_prev; + *back_res = coder->optimum[0].back_prev; + + return; +} + + +extern void +lzma_get_optimum(lzma_coder *restrict coder, + uint32_t *restrict back_res, uint32_t *restrict len_res) +{ + // Update the price tables. In the C++ LZMA SDK 4.42 this was done in both + // initialization function and in the main loop. In liblzma they were + // moved into this single place. + if (coder->additional_offset == 0) { + if (coder->match_price_count >= (1 << 7)) + fill_distances_prices(coder); + + if (coder->align_price_count >= ALIGN_TABLE_SIZE) + fill_align_prices(coder); + } + + + if (coder->optimum_end_index != coder->optimum_current_index) { + *len_res = coder->optimum[coder->optimum_current_index].pos_prev + - coder->optimum_current_index; + *back_res = coder->optimum[coder->optimum_current_index].back_prev; + coder->optimum_current_index = coder->optimum[ + coder->optimum_current_index].pos_prev; + return; + } + + coder->optimum_current_index = 0; + coder->optimum_end_index = 0; + + + const uint32_t fast_bytes = coder->fast_bytes; + uint32_t *match_distances = coder->match_distances; + + uint32_t len_main; + uint32_t num_distance_pairs; + + if (!coder->longest_match_was_found) { + lzma_read_match_distances(coder, &len_main, &num_distance_pairs); + } else { + len_main = coder->longest_match_length; + num_distance_pairs = coder->num_distance_pairs; + coder->longest_match_was_found = false; + } + + + const uint8_t *buf = coder->lz.buffer + coder->lz.read_pos - 1; + uint32_t num_available_bytes + = coder->lz.write_pos - coder->lz.read_pos + 1; + if (num_available_bytes < 2) { + *back_res = UINT32_MAX; + *len_res = 1; + return; + } + + if (num_available_bytes > MATCH_MAX_LEN) + num_available_bytes = MATCH_MAX_LEN; + + + uint32_t reps[REP_DISTANCES]; + uint32_t rep_lens[REP_DISTANCES]; + uint32_t rep_max_index = 0; + + for (uint32_t i = 0; i < REP_DISTANCES; ++i) { + reps[i] = coder->rep_distances[i]; + const uint32_t back_offset = reps[i] + 1; + + if (buf[0] != *(buf - back_offset) + || buf[1] != *(buf + 1 - back_offset)) { + rep_lens[i] = 0; + continue; + } + + uint32_t len_test; + for (len_test = 2; len_test < num_available_bytes + && buf[len_test] == *(buf + len_test - back_offset); + ++len_test) ; + + rep_lens[i] = len_test; + if (len_test > rep_lens[rep_max_index]) + rep_max_index = i; + } + + if (rep_lens[rep_max_index] >= fast_bytes) { + *back_res = rep_max_index; + *len_res = rep_lens[rep_max_index]; + move_pos(*len_res - 1); + return; + } + + + if (len_main >= fast_bytes) { + *back_res = match_distances[num_distance_pairs] + REP_DISTANCES; + *len_res = len_main; + move_pos(len_main - 1); + return; + } + + uint8_t current_byte = *buf; + uint8_t match_byte = *(buf - reps[0] - 1); + + if (len_main < 2 && current_byte != match_byte + && rep_lens[rep_max_index] < 2) { + *back_res = UINT32_MAX; + *len_res = 1; + return; + } + + const uint32_t pos_mask = coder->pos_mask; + + coder->optimum[0].state = coder->state; + + uint32_t position = coder->now_pos; + uint32_t pos_state = (position & pos_mask); + + coder->optimum[1].price = bit_get_price_0( + coder->is_match[coder->state][pos_state]) + + literal_get_price( + literal_get_subcoder(coder->literal_coder, + position, coder->previous_byte), + !is_char_state(coder->state), match_byte, current_byte); + + make_as_char(coder->optimum[1]); + + uint32_t match_price + = bit_get_price_1(coder->is_match[coder->state][pos_state]); + uint32_t rep_match_price + = match_price + bit_get_price_1(coder->is_rep[coder->state]); + + + if (match_byte == current_byte) { + const uint32_t short_rep_price = rep_match_price + + get_rep_len_1_price(coder->state, pos_state); + + if (short_rep_price < coder->optimum[1].price) { + coder->optimum[1].price = short_rep_price; + make_as_short_rep(coder->optimum[1]); + } + } + + uint32_t len_end = (len_main >= rep_lens[rep_max_index]) + ? len_main + : rep_lens[rep_max_index]; + + if (len_end < 2) { + *back_res = coder->optimum[1].back_prev; + *len_res = 1; + return; + } + + coder->optimum[1].pos_prev = 0; + + for (uint32_t i = 0; i < REP_DISTANCES; ++i) + coder->optimum[0].backs[i] = reps[i]; + + uint32_t len = len_end; + do { + coder->optimum[len].price = INFINITY_PRICE; + } while (--len >= 2); + + + uint32_t (*distances_prices)[FULL_DISTANCES] = coder->distances_prices; + uint32_t (*pos_slot_prices)[DIST_TABLE_SIZE_MAX] = coder->pos_slot_prices; + uint32_t *align_prices = coder->align_prices; + + for (uint32_t i = 0; i < REP_DISTANCES; ++i) { + uint32_t rep_len = rep_lens[i]; + if (rep_len < 2) + continue; + + uint32_t price = rep_match_price; + get_pure_rep_price(price, i, coder->state, pos_state); + + do { + const uint32_t cur_and_len_price = price + + length_get_price( + coder->rep_match_len_encoder, + rep_len - 2, pos_state); + + if (cur_and_len_price < coder->optimum[rep_len].price) { + coder->optimum[rep_len].price = cur_and_len_price; + coder->optimum[rep_len].pos_prev = 0; + coder->optimum[rep_len].back_prev = i; + coder->optimum[rep_len].prev_1_is_char = false; + } + } while (--rep_len >= 2); + } + + + uint32_t normal_match_price = match_price + + bit_get_price_0(coder->is_rep[coder->state]); + + len = (rep_lens[0] >= 2) ? rep_lens[0] + 1 : 2; + + if (len <= len_main) { + uint32_t offs = 0; + + while (len > match_distances[offs + 1]) + offs += 2; + + for(; ; ++len) { + const uint32_t distance = match_distances[offs + 2]; + uint32_t cur_and_len_price = normal_match_price; + get_pos_len_price(cur_and_len_price, distance, len, pos_state); + + if (cur_and_len_price < coder->optimum[len].price) { + coder->optimum[len].price = cur_and_len_price; + coder->optimum[len].pos_prev = 0; + coder->optimum[len].back_prev = distance + REP_DISTANCES; + coder->optimum[len].prev_1_is_char = false; + } + + if (len == match_distances[offs + 1]) { + offs += 2; + if (offs == num_distance_pairs) + break; + } + } + } + + + ////////////////// + // Big loop ;-) // + ////////////////// + + uint32_t cur = 0; + + // The rest of this function is a huge while-loop. To avoid extreme + // indentation, the indentation level is not increased here. + while (true) { + + ++cur; + + assert(cur < OPTS); + + if (cur == len_end) { + backward(coder, len_res, back_res, cur); + return; + } + + uint32_t new_len; + + lzma_read_match_distances(coder, &new_len, &num_distance_pairs); + + if (new_len >= fast_bytes) { + coder->num_distance_pairs = num_distance_pairs; + coder->longest_match_length = new_len; + coder->longest_match_was_found = true; + backward(coder, len_res, back_res, cur); + return; + } + + + ++position; + + uint32_t pos_prev = coder->optimum[cur].pos_prev; + uint32_t state; + + if (coder->optimum[cur].prev_1_is_char) { + --pos_prev; + + if (coder->optimum[cur].prev_2) { + state = coder->optimum[coder->optimum[cur].pos_prev_2].state; + + if (coder->optimum[cur].back_prev_2 < REP_DISTANCES) + update_rep(state); + else + update_match(state); + + } else { + state = coder->optimum[pos_prev].state; + } + + update_char(state); + + } else { + state = coder->optimum[pos_prev].state; + } + + if (pos_prev == cur - 1) { + if (is_short_rep(coder->optimum[cur])) + update_short_rep(state); + else + update_char(state); + } else { + uint32_t pos; + if (coder->optimum[cur].prev_1_is_char && coder->optimum[cur].prev_2) { + pos_prev = coder->optimum[cur].pos_prev_2; + pos = coder->optimum[cur].back_prev_2; + update_rep(state); + } else { + pos = coder->optimum[cur].back_prev; + if (pos < REP_DISTANCES) + update_rep(state); + else + update_match(state); + } + + if (pos < REP_DISTANCES) { + reps[0] = coder->optimum[pos_prev].backs[pos]; + + uint32_t i; + for (i = 1; i <= pos; ++i) + reps[i] = coder->optimum[pos_prev].backs[i - 1]; + + for (; i < REP_DISTANCES; ++i) + reps[i] = coder->optimum[pos_prev].backs[i]; + + } else { + reps[0] = pos - REP_DISTANCES; + + for (uint32_t i = 1; i < REP_DISTANCES; ++i) + reps[i] = coder->optimum[pos_prev].backs[i - 1]; + } + } + + coder->optimum[cur].state = state; + + for (uint32_t i = 0; i < REP_DISTANCES; ++i) + coder->optimum[cur].backs[i] = reps[i]; + + const uint32_t cur_price = coder->optimum[cur].price; + + buf = coder->lz.buffer + coder->lz.read_pos - 1; + current_byte = *buf; + match_byte = *(buf - reps[0] - 1); + + pos_state = position & pos_mask; + + const uint32_t cur_and_1_price = cur_price + + bit_get_price_0(coder->is_match[state][pos_state]) + + literal_get_price( + literal_get_subcoder(coder->literal_coder, + position, buf[-1]), + !is_char_state(state), match_byte, current_byte); + + bool next_is_char = false; + + if (cur_and_1_price < coder->optimum[cur + 1].price) { + coder->optimum[cur + 1].price = cur_and_1_price; + coder->optimum[cur + 1].pos_prev = cur; + make_as_char(coder->optimum[cur + 1]); + next_is_char = true; + } + + match_price = cur_price + + bit_get_price_1(coder->is_match[state][pos_state]); + rep_match_price = match_price + + bit_get_price_1(coder->is_rep[state]); + + if (match_byte == current_byte + && !(coder->optimum[cur + 1].pos_prev < cur + && coder->optimum[cur + 1].back_prev == 0)) { + + const uint32_t short_rep_price = rep_match_price + + get_rep_len_1_price(state, pos_state); + + if (short_rep_price <= coder->optimum[cur + 1].price) { + coder->optimum[cur + 1].price = short_rep_price; + coder->optimum[cur + 1].pos_prev = cur; + make_as_short_rep(coder->optimum[cur + 1]); + next_is_char = true; + } + } + + uint32_t num_available_bytes_full + = coder->lz.write_pos - coder->lz.read_pos + 1; + num_available_bytes_full = MIN(OPTS - 1 - cur, num_available_bytes_full); + num_available_bytes = num_available_bytes_full; + + if (num_available_bytes < 2) + continue; + + if (num_available_bytes > fast_bytes) + num_available_bytes = fast_bytes; + + if (!next_is_char && match_byte != current_byte) { // speed optimization + // try literal + rep0 + const uint32_t back_offset = reps[0] + 1; + const uint32_t limit = MIN(num_available_bytes_full, fast_bytes + 1); + + uint32_t temp; + for (temp = 1; temp < limit + && buf[temp] == *(buf + temp - back_offset); + ++temp) ; + + const uint32_t len_test_2 = temp - 1; + + if (len_test_2 >= 2) { + uint32_t state_2 = state; + update_char(state_2); + + const uint32_t pos_state_next = (position + 1) & pos_mask; + const uint32_t next_rep_match_price = cur_and_1_price + + bit_get_price_1(coder->is_match[state_2][pos_state_next]) + + bit_get_price_1(coder->is_rep[state_2]); + + // for (; len_test_2 >= 2; --len_test_2) { + const uint32_t offset = cur + 1 + len_test_2; + + while (len_end < offset) + coder->optimum[++len_end].price = INFINITY_PRICE; + + uint32_t cur_and_len_price = next_rep_match_price; + get_rep_price(cur_and_len_price, + 0, len_test_2, state_2, pos_state_next); + + if (cur_and_len_price < coder->optimum[offset].price) { + coder->optimum[offset].price = cur_and_len_price; + coder->optimum[offset].pos_prev = cur + 1; + coder->optimum[offset].back_prev = 0; + coder->optimum[offset].prev_1_is_char = true; + coder->optimum[offset].prev_2 = false; + } +// } + } + } + + + uint32_t start_len = 2; // speed optimization + + for (uint32_t rep_index = 0; rep_index < REP_DISTANCES; ++rep_index) { + const uint32_t back_offset = reps[rep_index] + 1; + + if (buf[0] != *(buf - back_offset) || buf[1] != *(buf + 1 - back_offset)) + continue; + + uint32_t len_test; + for (len_test = 2; len_test < num_available_bytes + && buf[len_test] == *(buf + len_test - back_offset); + ++len_test) ; + + while (len_end < cur + len_test) + coder->optimum[++len_end].price = INFINITY_PRICE; + + const uint32_t len_test_temp = len_test; + uint32_t price = rep_match_price; + get_pure_rep_price(price, rep_index, state, pos_state); + + do { + const uint32_t cur_and_len_price = price + + length_get_price(coder->rep_match_len_encoder, + len_test - 2, pos_state); + + if (cur_and_len_price < coder->optimum[cur + len_test].price) { + coder->optimum[cur + len_test].price = cur_and_len_price; + coder->optimum[cur + len_test].pos_prev = cur; + coder->optimum[cur + len_test].back_prev = rep_index; + coder->optimum[cur + len_test].prev_1_is_char = false; + } + } while (--len_test >= 2); + + len_test = len_test_temp; + + if (rep_index == 0) + start_len = len_test + 1; + + + uint32_t len_test_2 = len_test + 1; + const uint32_t limit = MIN(num_available_bytes_full, + len_test_2 + fast_bytes); + for (; len_test_2 < limit + && buf[len_test_2] == *(buf + len_test_2 - back_offset); + ++len_test_2) ; + + len_test_2 -= len_test + 1; + + if (len_test_2 >= 2) { + uint32_t state_2 = state; + update_rep(state_2); + + uint32_t pos_state_next = (position + len_test) & pos_mask; + + const uint32_t cur_and_len_char_price = price + + length_get_price(coder->rep_match_len_encoder, + len_test - 2, pos_state) + + bit_get_price_0(coder->is_match[state_2][pos_state_next]) + + literal_get_price( + literal_get_subcoder(coder->literal_coder, + position + len_test, buf[len_test - 1]), + true, *(buf + len_test - back_offset), buf[len_test]); + + update_char(state_2); + + pos_state_next = (position + len_test + 1) & pos_mask; + + const uint32_t next_rep_match_price = cur_and_len_char_price + + bit_get_price_1(coder->is_match[state_2][pos_state_next]) + + bit_get_price_1(coder->is_rep[state_2]); + +// for(; len_test_2 >= 2; len_test_2--) { + const uint32_t offset = cur + len_test + 1 + len_test_2; + + while (len_end < offset) + coder->optimum[++len_end].price = INFINITY_PRICE; + + uint32_t cur_and_len_price = next_rep_match_price; + get_rep_price(cur_and_len_price, + 0, len_test_2, state_2, pos_state_next); + + if (cur_and_len_price < coder->optimum[offset].price) { + coder->optimum[offset].price = cur_and_len_price; + coder->optimum[offset].pos_prev = cur + len_test + 1; + coder->optimum[offset].back_prev = 0; + coder->optimum[offset].prev_1_is_char = true; + coder->optimum[offset].prev_2 = true; + coder->optimum[offset].pos_prev_2 = cur; + coder->optimum[offset].back_prev_2 = rep_index; + } +// } + } + } + + +// for (uint32_t len_test = 2; len_test <= new_len; ++len_test) + if (new_len > num_available_bytes) { + new_len = num_available_bytes; + + for (num_distance_pairs = 0; + new_len > match_distances[num_distance_pairs + 1]; + num_distance_pairs += 2) ; + + match_distances[num_distance_pairs + 1] = new_len; + num_distance_pairs += 2; + } + + + if (new_len >= start_len) { + normal_match_price = match_price + + bit_get_price_0(coder->is_rep[state]); + + while (len_end < cur + new_len) + coder->optimum[++len_end].price = INFINITY_PRICE; + + uint32_t offs = 0; + while (start_len > match_distances[offs + 1]) + offs += 2; + + uint32_t cur_back = match_distances[offs + 2]; + uint32_t pos_slot = get_pos_slot_2(cur_back); + + for (uint32_t len_test = start_len; ; ++len_test) { + uint32_t cur_and_len_price = normal_match_price; + const uint32_t len_to_pos_state = get_len_to_pos_state(len_test); + + if (cur_back < FULL_DISTANCES) + cur_and_len_price += distances_prices[ + len_to_pos_state][cur_back]; + else + cur_and_len_price += pos_slot_prices[ + len_to_pos_state][pos_slot] + + align_prices[cur_back & ALIGN_MASK]; + + cur_and_len_price += length_get_price(coder->len_encoder, + len_test - MATCH_MIN_LEN, pos_state); + + if (cur_and_len_price < coder->optimum[cur + len_test].price) { + coder->optimum[cur + len_test].price = cur_and_len_price; + coder->optimum[cur + len_test].pos_prev = cur; + coder->optimum[cur + len_test].back_prev + = cur_back + REP_DISTANCES; + coder->optimum[cur + len_test].prev_1_is_char = false; + } + + if (len_test == match_distances[offs + 1]) { + // Try Match + Literal + Rep0 + const uint32_t back_offset = cur_back + 1; + uint32_t len_test_2 = len_test + 1; + const uint32_t limit = MIN(num_available_bytes_full, + len_test_2 + fast_bytes); + + for (; len_test_2 < limit && + buf[len_test_2] == *(buf + len_test_2 - back_offset); + ++len_test_2) ; + + len_test_2 -= len_test + 1; + + if (len_test_2 >= 2) { + uint32_t state_2 = state; + update_match(state_2); + uint32_t pos_state_next + = (position + len_test) & pos_mask; + + const uint32_t cur_and_len_char_price = cur_and_len_price + + bit_get_price_0( + coder->is_match[state_2][pos_state_next]) + + literal_get_price( + literal_get_subcoder( + coder->literal_coder, + position + len_test, + buf[len_test - 1]), + true, + *(buf + len_test - back_offset), + buf[len_test]); + + update_char(state_2); + pos_state_next = (pos_state_next + 1) & pos_mask; + + const uint32_t next_rep_match_price + = cur_and_len_char_price + + bit_get_price_1( + coder->is_match[state_2][pos_state_next]) + + bit_get_price_1(coder->is_rep[state_2]); + + // for(; len_test_2 >= 2; --len_test_2) { + const uint32_t offset = cur + len_test + 1 + len_test_2; + + while (len_end < offset) + coder->optimum[++len_end].price = INFINITY_PRICE; + + cur_and_len_price = next_rep_match_price; + get_rep_price(cur_and_len_price, + 0, len_test_2, state_2, pos_state_next); + + if (cur_and_len_price < coder->optimum[offset].price) { + coder->optimum[offset].price = cur_and_len_price; + coder->optimum[offset].pos_prev = cur + len_test + 1; + coder->optimum[offset].back_prev = 0; + coder->optimum[offset].prev_1_is_char = true; + coder->optimum[offset].prev_2 = true; + coder->optimum[offset].pos_prev_2 = cur; + coder->optimum[offset].back_prev_2 + = cur_back + REP_DISTANCES; + } +// } + } + + offs += 2; + if (offs == num_distance_pairs) + break; + + cur_back = match_distances[offs + 2]; + if (cur_back >= FULL_DISTANCES) + pos_slot = get_pos_slot_2(cur_back); + } + } + } + + } // Closes: while (true) +} |