diff options
Diffstat (limited to '')
| -rw-r--r-- | encoder.c | 131 |
1 files changed, 59 insertions, 72 deletions
@@ -1,5 +1,5 @@ /* Clzip - LZMA lossless data compressor - Copyright (C) 2010-2021 Antonio Diaz Diaz. + Copyright (C) 2010-2022 Antonio Diaz Diaz. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -33,32 +33,25 @@ CRC32 crc32; int LZe_get_match_pairs( struct LZ_encoder * const e, struct Pair * pairs ) { - int32_t * ptr0 = e->eb.mb.pos_array + ( e->eb.mb.cyclic_pos << 1 ); - int32_t * ptr1 = ptr0 + 1; - int32_t * newptr; - int len = 0, len0 = 0, len1 = 0; - int maxlen = 3; /* only used if pairs != 0 */ - int num_pairs = 0; - const int pos1 = e->eb.mb.pos + 1; - const int min_pos = ( e->eb.mb.pos > e->eb.mb.dictionary_size ) ? - e->eb.mb.pos - e->eb.mb.dictionary_size : 0; - const uint8_t * const data = Mb_ptr_to_current_pos( &e->eb.mb ); - int count, key2, key3, key4, newpos1; - unsigned tmp; int len_limit = e->match_len_limit; - if( len_limit > Mb_available_bytes( &e->eb.mb ) ) { len_limit = Mb_available_bytes( &e->eb.mb ); if( len_limit < 4 ) return 0; } - tmp = crc32[data[0]] ^ data[1]; - key2 = tmp & ( num_prev_positions2 - 1 ); + int maxlen = 3; /* only used if pairs != 0 */ + int num_pairs = 0; + const int min_pos = ( e->eb.mb.pos > e->eb.mb.dictionary_size ) ? + e->eb.mb.pos - e->eb.mb.dictionary_size : 0; + const uint8_t * const data = Mb_ptr_to_current_pos( &e->eb.mb ); + + unsigned tmp = crc32[data[0]] ^ data[1]; + const int key2 = tmp & ( num_prev_positions2 - 1 ); tmp ^= (unsigned)data[2] << 8; - key3 = num_prev_positions2 + ( tmp & ( num_prev_positions3 - 1 ) ); - key4 = num_prev_positions2 + num_prev_positions3 + - ( ( tmp ^ ( crc32[data[3]] << 5 ) ) & e->eb.mb.key4_mask ); + const int key3 = num_prev_positions2 + ( tmp & ( num_prev_positions3 - 1 ) ); + const int key4 = num_prev_positions2 + num_prev_positions3 + + ( ( tmp ^ ( crc32[data[3]] << 5 ) ) & e->eb.mb.key4_mask ); if( pairs ) { @@ -67,7 +60,7 @@ int LZe_get_match_pairs( struct LZ_encoder * const e, struct Pair * pairs ) if( np2 > min_pos && e->eb.mb.buffer[np2-1] == data[0] ) { pairs[0].dis = e->eb.mb.pos - np2; - pairs[0].len = maxlen = 2; + pairs[0].len = maxlen = 2 + ( np2 == np3 ); num_pairs = 1; } if( np2 != np3 && np3 > min_pos && e->eb.mb.buffer[np3-1] == data[0] ) @@ -86,18 +79,23 @@ int LZe_get_match_pairs( struct LZ_encoder * const e, struct Pair * pairs ) } } + const int pos1 = e->eb.mb.pos + 1; e->eb.mb.prev_positions[key2] = pos1; e->eb.mb.prev_positions[key3] = pos1; - newpos1 = e->eb.mb.prev_positions[key4]; + int newpos1 = e->eb.mb.prev_positions[key4]; e->eb.mb.prev_positions[key4] = pos1; + int32_t * ptr0 = e->eb.mb.pos_array + ( e->eb.mb.cyclic_pos << 1 ); + int32_t * ptr1 = ptr0 + 1; + int len = 0, len0 = 0, len1 = 0; + + int count; for( count = e->cycles; ; ) { - int delta; if( newpos1 <= min_pos || --count < 0 ) { *ptr0 = *ptr1 = 0; break; } - delta = pos1 - newpos1; - newptr = e->eb.mb.pos_array + + const int delta = pos1 - newpos1; + int32_t * const newptr = e->eb.mb.pos_array + ( ( e->eb.mb.cyclic_pos - delta + ( (e->eb.mb.cyclic_pos >= delta) ? 0 : e->eb.mb.dictionary_size + 1 ) ) << 1 ); if( data[len-delta] == data[len] ) @@ -152,7 +150,6 @@ static void LZe_update_distance_prices( struct LZ_encoder * const e ) for( len_state = 0; len_state < len_states; ++len_state ) { int * const dsp = e->dis_slot_prices[len_state]; - int * const dp = e->dis_prices[len_state]; const Bit_model * const bmds = e->eb.bm_dis_slot[len_state]; int slot = 0; for( ; slot < end_dis_model; ++slot ) @@ -161,6 +158,7 @@ static void LZe_update_distance_prices( struct LZ_encoder * const e ) dsp[slot] = price_symbol6( bmds, slot ) + (((( slot >> 1 ) - 1 ) - dis_align_bits ) << price_shift_bits ); + int * const dp = e->dis_prices[len_state]; for( dis = 0; dis < start_dis_model; ++dis ) dp[dis] = dsp[dis]; for( ; dis < modeled_distances; ++dis ) @@ -169,7 +167,7 @@ static void LZe_update_distance_prices( struct LZ_encoder * const e ) } -/* Returns the number of bytes advanced (ahead). +/* Return the number of bytes advanced (ahead). trials[0]..trials[ahead-1] contain the steps to encode. ( trials[0].dis4 == -1 ) means literal. A match/rep longer or equal than match_len_limit finishes the sequence. @@ -178,9 +176,8 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, const int reps[num_rep_distances], const State state ) { - int main_len, num_pairs, i, rep, num_trials, len; - int rep_index = 0, cur = 0; - int replens[num_rep_distances]; + int num_pairs, num_trials; + int i, rep, len; if( e->pending_num_pairs > 0 ) /* from previous call */ { @@ -189,8 +186,10 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, } else num_pairs = LZe_read_match_distances( e ); - main_len = ( num_pairs > 0 ) ? e->pairs[num_pairs-1].len : 0; + const int main_len = ( num_pairs > 0 ) ? e->pairs[num_pairs-1].len : 0; + int replens[num_rep_distances]; + int rep_index = 0; for( i = 0; i < num_rep_distances; ++i ) { replens[i] = Mb_true_match_len( &e->eb.mb, 0, reps[i] + 1 ); @@ -212,10 +211,7 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, return main_len; } - { const int pos_state = Mb_data_position( &e->eb.mb ) & pos_state_mask; - const int match_price = price1( e->eb.bm_match[state][pos_state] ); - const int rep_match_price = match_price + price1( e->eb.bm_rep[state] ); const uint8_t prev_byte = Mb_peek( &e->eb.mb, 1 ); const uint8_t cur_byte = Mb_peek( &e->eb.mb, 0 ); const uint8_t match_byte = Mb_peek( &e->eb.mb, reps[0] + 1 ); @@ -227,6 +223,9 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, e->trials[1].price += LZeb_price_matched( &e->eb, prev_byte, cur_byte, match_byte ); e->trials[1].dis4 = -1; /* literal */ + const int match_price = price1( e->eb.bm_match[state][pos_state] ); + const int rep_match_price = match_price + price1( e->eb.bm_rep[state] ); + if( match_byte == cur_byte ) Tr_update( &e->trials[1], rep_match_price + LZeb_price_shortrep( &e->eb, state, pos_state ), 0, 0 ); @@ -250,9 +249,8 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, for( rep = 0; rep < num_rep_distances; ++rep ) { - int price; if( replens[rep] < min_match_len ) continue; - price = rep_match_price + LZeb_price_rep( &e->eb, rep, state, pos_state ); + const int price = rep_match_price + LZeb_price_rep( &e->eb, rep, state, pos_state ); for( len = min_match_len; len <= replens[rep]; ++len ) Tr_update( &e->trials[len], price + Lp_price( &e->rep_len_prices, len, pos_state ), rep, 0 ); @@ -272,17 +270,10 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, if( ++len > e->pairs[i].len && ++i >= num_pairs ) break; } } - } + int cur = 0; while( true ) /* price optimization loop */ { - struct Trial *cur_trial, *next_trial; - int newlen, pos_state, triable_bytes, len_limit; - int start_len = min_match_len; - int next_price, match_price, rep_match_price; - State cur_state; - uint8_t prev_byte, cur_byte, match_byte; - Mb_move_pos( &e->eb.mb ); if( ++cur >= num_trials ) /* no more initialized trials */ { @@ -290,8 +281,8 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, return cur; } - num_pairs = LZe_read_match_distances( e ); - newlen = ( num_pairs > 0 ) ? e->pairs[num_pairs-1].len : 0; + const int num_pairs = LZe_read_match_distances( e ); + const int newlen = ( num_pairs > 0 ) ? e->pairs[num_pairs-1].len : 0; if( newlen >= e->match_len_limit ) { e->pending_num_pairs = num_pairs; @@ -300,7 +291,8 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, } /* give final values to current trial */ - cur_trial = &e->trials[cur]; + struct Trial * cur_trial = &e->trials[cur]; + State cur_state; { const int dis4 = cur_trial->dis4; int prev_index = cur_trial->prev_index; @@ -331,25 +323,25 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, mtf_reps( dis4, cur_trial->reps ); /* literal is ignored */ } - pos_state = Mb_data_position( &e->eb.mb ) & pos_state_mask; - prev_byte = Mb_peek( &e->eb.mb, 1 ); - cur_byte = Mb_peek( &e->eb.mb, 0 ); - match_byte = Mb_peek( &e->eb.mb, cur_trial->reps[0] + 1 ); + const int pos_state = Mb_data_position( &e->eb.mb ) & pos_state_mask; + const uint8_t prev_byte = Mb_peek( &e->eb.mb, 1 ); + const uint8_t cur_byte = Mb_peek( &e->eb.mb, 0 ); + const uint8_t match_byte = Mb_peek( &e->eb.mb, cur_trial->reps[0] + 1 ); - next_price = cur_trial->price + - price0( e->eb.bm_match[cur_state][pos_state] ); + int next_price = cur_trial->price + + price0( e->eb.bm_match[cur_state][pos_state] ); if( St_is_char( cur_state ) ) next_price += LZeb_price_literal( &e->eb, prev_byte, cur_byte ); else next_price += LZeb_price_matched( &e->eb, prev_byte, cur_byte, match_byte ); /* try last updates to next trial */ - next_trial = &e->trials[cur+1]; + struct Trial * next_trial = &e->trials[cur+1]; Tr_update( next_trial, next_price, -1, cur ); /* literal */ - match_price = cur_trial->price + price1( e->eb.bm_match[cur_state][pos_state] ); - rep_match_price = match_price + price1( e->eb.bm_rep[cur_state] ); + const int match_price = cur_trial->price + price1( e->eb.bm_match[cur_state][pos_state] ); + const int rep_match_price = match_price + price1( e->eb.bm_rep[cur_state] ); if( match_byte == cur_byte && next_trial->dis4 != 0 && next_trial->prev_index2 == single_step_trial ) @@ -364,11 +356,11 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, } } - triable_bytes = + const int triable_bytes = min( Mb_available_bytes( &e->eb.mb ), max_num_trials - 1 - cur ); if( triable_bytes < min_match_len ) continue; - len_limit = min( e->match_len_limit, triable_bytes ); + const int len_limit = min( e->match_len_limit, triable_bytes ); /* try literal + rep0 */ if( match_byte != cur_byte && next_trial->prev_index != cur ) @@ -392,19 +384,20 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, } } + int start_len = min_match_len; + /* try rep distances */ for( rep = 0; rep < num_rep_distances; ++rep ) { const uint8_t * const data = Mb_ptr_to_current_pos( &e->eb.mb ); const int dis = cur_trial->reps[rep] + 1; - int price; if( data[0-dis] != data[0] || data[1-dis] != data[1] ) continue; for( len = min_match_len; len < len_limit; ++len ) if( data[len-dis] != data[len] ) break; while( num_trials < cur + len ) e->trials[++num_trials].price = infinite_price; - price = rep_match_price + LZeb_price_rep( &e->eb, rep, cur_state, pos_state ); + int price = rep_match_price + LZeb_price_rep( &e->eb, rep, cur_state, pos_state ); for( i = min_match_len; i <= len; ++i ) Tr_update( &e->trials[cur+i], price + Lp_price( &e->rep_len_prices, i, pos_state ), rep, cur ); @@ -412,17 +405,14 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, if( rep == 0 ) start_len = len + 1; /* discard shorter matches */ /* try rep + literal + rep0 */ - { int len2 = len + 1; const int limit = min( e->match_len_limit + len2, triable_bytes ); - int pos_state2; - State state2; while( len2 < limit && data[len2-dis] == data[len2] ) ++len2; len2 -= len + 1; if( len2 < min_match_len ) continue; - pos_state2 = ( pos_state + len ) & pos_state_mask; - state2 = St_set_rep( cur_state ); + int pos_state2 = ( pos_state + len ) & pos_state_mask; + State state2 = St_set_rep( cur_state ); price += Lp_price( &e->rep_len_prices, len, pos_state ) + price0( e->eb.bm_match[state2][pos_state2] ) + LZeb_price_matched( &e->eb, data[len-1], data[len], data[len-dis] ); @@ -435,21 +425,19 @@ static int LZe_sequence_optimizer( struct LZ_encoder * const e, e->trials[++num_trials].price = infinite_price; Tr_update3( &e->trials[cur+len+1+len2], price, rep, cur + len + 1, cur ); } - } /* try matches */ if( newlen >= start_len && newlen <= len_limit ) { - int dis; const int normal_match_price = match_price + price0( e->eb.bm_rep[cur_state] ); while( num_trials < cur + newlen ) e->trials[++num_trials].price = infinite_price; - i = 0; + int i = 0; while( e->pairs[i].len < start_len ) ++i; - dis = e->pairs[i].dis; + int dis = e->pairs[i].dis; for( len = start_len; ; ++len ) { int price = normal_match_price + LZe_price_pair( e, dis, len, pos_state ); @@ -502,7 +490,7 @@ bool LZe_encode_member( struct LZ_encoder * const e, int price_counter = 0; /* counters may decrement below 0 */ int dis_price_counter = 0; int align_price_counter = 0; - int ahead, i; + int i; int reps[num_rep_distances]; State state = 0; for( i = 0; i < num_rep_distances; ++i ) reps[i] = 0; @@ -539,7 +527,7 @@ bool LZe_encode_member( struct LZ_encoder * const e, Lp_update_prices( &e->rep_len_prices ); } - ahead = LZe_sequence_optimizer( e, reps, state ); + int ahead = LZe_sequence_optimizer( e, reps, state ); price_counter -= ahead; for( i = 0; ahead > 0; ) @@ -556,14 +544,13 @@ bool LZe_encode_member( struct LZ_encoder * const e, const uint8_t prev_byte = Mb_peek( &e->eb.mb, ahead + 1 ); const uint8_t cur_byte = Mb_peek( &e->eb.mb, ahead ); CRC32_update_byte( &e->eb.crc, cur_byte ); - if( St_is_char( state ) ) + if( ( state = St_set_char( state ) ) < 4 ) LZeb_encode_literal( &e->eb, prev_byte, cur_byte ); else { const uint8_t match_byte = Mb_peek( &e->eb.mb, ahead + reps[0] + 1 ); LZeb_encode_matched( &e->eb, prev_byte, cur_byte, match_byte ); } - state = St_set_char( state ); } else /* match or repeated match */ { |