From 974ebe63497bdf0d262e06474f0dd5a70b1dd000 Mon Sep 17 00:00:00 2001 From: Lasse Collin Date: Tue, 26 Oct 2010 10:36:41 +0300 Subject: [PATCH] liblzma: Rename a few variables and constants. This has no semantic changes. I find the new names slightly more logical and they match the names that are already used in XZ Embedded. The name fastpos wasn't changed (not worth the hassle). --- src/liblzma/lzma/fastpos.h | 55 ++++---- src/liblzma/lzma/lzma2_encoder.c | 2 +- src/liblzma/lzma/lzma_common.h | 45 +++--- src/liblzma/lzma/lzma_decoder.c | 58 ++++---- src/liblzma/lzma/lzma_encoder.c | 56 ++++---- src/liblzma/lzma/lzma_encoder_optimum_fast.c | 9 +- .../lzma/lzma_encoder_optimum_normal.c | 128 +++++++++--------- src/liblzma/lzma/lzma_encoder_private.h | 16 +-- 8 files changed, 183 insertions(+), 186 deletions(-) diff --git a/src/liblzma/lzma/fastpos.h b/src/liblzma/lzma/fastpos.h index 4aea231..a3feea5 100644 --- a/src/liblzma/lzma/fastpos.h +++ b/src/liblzma/lzma/fastpos.h @@ -14,15 +14,15 @@ #ifndef LZMA_FASTPOS_H #define LZMA_FASTPOS_H -// LZMA encodes match distances (positions) by storing the highest two -// bits using a six-bit value [0, 63], and then the missing lower bits. -// Dictionary size is also stored using this encoding in the new .lzma +// LZMA encodes match distances by storing the highest two bits using +// a six-bit value [0, 63], and then the missing lower bits. +// Dictionary size is also stored using this encoding in the .xz // file format header. // // fastpos.h provides a way to quickly find out the correct six-bit // values. The following table gives some examples of this encoding: // -// pos return +// dist return // 0 0 // 1 1 // 2 2 @@ -48,10 +48,10 @@ // Provided functions or macros // ---------------------------- // -// get_pos_slot(pos) is the basic version. get_pos_slot_2(pos) -// assumes that pos >= FULL_DISTANCES, thus the result is at least -// FULL_DISTANCES_BITS * 2. Using get_pos_slot(pos) instead of -// get_pos_slot_2(pos) would give the same result, but get_pos_slot_2(pos) +// get_dist_slot(dist) is the basic version. get_dist_slot_2(dist) +// assumes that dist >= FULL_DISTANCES, thus the result is at least +// FULL_DISTANCES_BITS * 2. Using get_dist_slot(dist) instead of +// get_dist_slot_2(dist) would give the same result, but get_dist_slot_2(dist) // should be tiny bit faster due to the assumption being made. // // @@ -76,13 +76,14 @@ // slightly faster, but sometimes it is a lot slower. #ifdef HAVE_SMALL -# define get_pos_slot(pos) ((pos) <= 4 ? (pos) : get_pos_slot_2(pos)) +# define get_dist_slot(dist) \ + ((dist) <= 4 ? (dist) : get_dist_slot_2(dist)) static inline uint32_t -get_pos_slot_2(uint32_t pos) +get_dist_slot_2(uint32_t dist) { - const uint32_t i = bsr32(pos); - return (i + i) + ((pos >> (i - 1)) & 1); + const uint32_t i = bsr32(dist); + return (i + i) + ((dist >> (i - 1)) & 1); } @@ -99,39 +100,39 @@ extern const uint8_t lzma_fastpos[1 << FASTPOS_BITS]; #define fastpos_limit(extra, n) \ (UINT32_C(1) << (FASTPOS_BITS + fastpos_shift(extra, n))) -#define fastpos_result(pos, extra, n) \ - lzma_fastpos[(pos) >> fastpos_shift(extra, n)] \ +#define fastpos_result(dist, extra, n) \ + lzma_fastpos[(dist) >> fastpos_shift(extra, n)] \ + 2 * fastpos_shift(extra, n) static inline uint32_t -get_pos_slot(uint32_t pos) +get_dist_slot(uint32_t dist) { // If it is small enough, we can pick the result directly from // the precalculated table. - if (pos < fastpos_limit(0, 0)) - return lzma_fastpos[pos]; + if (dist < fastpos_limit(0, 0)) + return lzma_fastpos[dist]; - if (pos < fastpos_limit(0, 1)) - return fastpos_result(pos, 0, 1); + if (dist < fastpos_limit(0, 1)) + return fastpos_result(dist, 0, 1); - return fastpos_result(pos, 0, 2); + return fastpos_result(dist, 0, 2); } #ifdef FULL_DISTANCES_BITS static inline uint32_t -get_pos_slot_2(uint32_t pos) +get_dist_slot_2(uint32_t dist) { - assert(pos >= FULL_DISTANCES); + assert(dist >= FULL_DISTANCES); - if (pos < fastpos_limit(FULL_DISTANCES_BITS - 1, 0)) - return fastpos_result(pos, FULL_DISTANCES_BITS - 1, 0); + if (dist < fastpos_limit(FULL_DISTANCES_BITS - 1, 0)) + return fastpos_result(dist, FULL_DISTANCES_BITS - 1, 0); - if (pos < fastpos_limit(FULL_DISTANCES_BITS - 1, 1)) - return fastpos_result(pos, FULL_DISTANCES_BITS - 1, 1); + if (dist < fastpos_limit(FULL_DISTANCES_BITS - 1, 1)) + return fastpos_result(dist, FULL_DISTANCES_BITS - 1, 1); - return fastpos_result(pos, FULL_DISTANCES_BITS - 1, 2); + return fastpos_result(dist, FULL_DISTANCES_BITS - 1, 2); } #endif diff --git a/src/liblzma/lzma/lzma2_encoder.c b/src/liblzma/lzma/lzma2_encoder.c index b48e0d6..e734bc5 100644 --- a/src/liblzma/lzma/lzma2_encoder.c +++ b/src/liblzma/lzma/lzma2_encoder.c @@ -387,7 +387,7 @@ lzma_lzma2_props_encode(const void *options, uint8_t *out) if (d == UINT32_MAX) out[0] = 40; else - out[0] = get_pos_slot(d + 1) - 24; + out[0] = get_dist_slot(d + 1) - 24; return LZMA_OK; } diff --git a/src/liblzma/lzma/lzma_common.h b/src/liblzma/lzma/lzma_common.h index e31e285..09efd38 100644 --- a/src/liblzma/lzma/lzma_common.h +++ b/src/liblzma/lzma/lzma_common.h @@ -171,53 +171,54 @@ literal_init(probability (*probs)[LITERAL_CODER_SIZE], // Match distance // //////////////////// -// Different set of probabilities is used for match distances that have very +// Different sets of probabilities are used for match distances that have very // short match length: Lengths of 2, 3, and 4 bytes have a separate set of // probabilities for each length. The matches with longer length use a shared // set of probabilities. -#define LEN_TO_POS_STATES 4 +#define DIST_STATES 4 // Macro to get the index of the appropriate probability array. -#define get_len_to_pos_state(len) \ - ((len) < LEN_TO_POS_STATES + MATCH_LEN_MIN \ +#define get_dist_state(len) \ + ((len) < DIST_STATES + MATCH_LEN_MIN \ ? (len) - MATCH_LEN_MIN \ - : LEN_TO_POS_STATES - 1) + : DIST_STATES - 1) -// The highest two bits of a match distance (pos slot) are encoded using six -// bits. See fastpos.h for more explanation. -#define POS_SLOT_BITS 6 -#define POS_SLOTS (1 << POS_SLOT_BITS) +// The highest two bits of a match distance (distance slot) are encoded +// using six bits. See fastpos.h for more explanation. +#define DIST_SLOT_BITS 6 +#define DIST_SLOTS (1 << DIST_SLOT_BITS) // Match distances up to 127 are fully encoded using probabilities. Since -// the highest two bits (pos slot) are always encoded using six bits, the -// distances 0-3 don't need any additional bits to encode, since the pos -// slot itself is the same as the actual distance. START_POS_MODEL_INDEX -// indicates the first pos slot where at least one additional bit is needed. -#define START_POS_MODEL_INDEX 4 +// the highest two bits (distance slot) are always encoded using six bits, +// the distances 0-3 don't need any additional bits to encode, since the +// distance slot itself is the same as the actual distance. DIST_MODEL_START +// indicates the first distance slot where at least one additional bit is +// needed. +#define DIST_MODEL_START 4 // Match distances greater than 127 are encoded in three pieces: -// - pos slot: the highest two bits +// - distance slot: the highest two bits // - direct bits: 2-26 bits below the highest two bits // - alignment bits: four lowest bits // // Direct bits don't use any probabilities. // -// The pos slot value of 14 is for distances 128-191 (see the table in +// The distance slot value of 14 is for distances 128-191 (see the table in // fastpos.h to understand why). -#define END_POS_MODEL_INDEX 14 +#define DIST_MODEL_END 14 -// Pos slots that indicate a distance <= 127. -#define FULL_DISTANCES_BITS (END_POS_MODEL_INDEX / 2) +// Distance slots that indicate a distance <= 127. +#define FULL_DISTANCES_BITS (DIST_MODEL_END / 2) #define FULL_DISTANCES (1 << FULL_DISTANCES_BITS) // For match distances greater than 127, only the highest two bits and the // lowest four bits (alignment) is encoded using probabilities. #define ALIGN_BITS 4 -#define ALIGN_TABLE_SIZE (1 << ALIGN_BITS) -#define ALIGN_MASK (ALIGN_TABLE_SIZE - 1) +#define ALIGN_SIZE (1 << ALIGN_BITS) +#define ALIGN_MASK (ALIGN_SIZE - 1) // LZMA remembers the four most recent match distances. Reusing these distances // tends to take less space than re-encoding the actual distance value. -#define REP_DISTANCES 4 +#define REPS 4 #endif diff --git a/src/liblzma/lzma/lzma_decoder.c b/src/liblzma/lzma/lzma_decoder.c index 9979bb4..d61b7de 100644 --- a/src/liblzma/lzma/lzma_decoder.c +++ b/src/liblzma/lzma/lzma_decoder.c @@ -193,15 +193,15 @@ struct lzma_coder_s { /// Probability tree for the highest two bits of the match distance. /// There is a separate probability tree for match lengths of /// 2 (i.e. MATCH_LEN_MIN), 3, 4, and [5, 273]. - probability pos_slot[LEN_TO_POS_STATES][POS_SLOTS]; + probability dist_slot[DIST_STATES][DIST_SLOTS]; /// Probability trees for additional bits for match distance when the /// distance is in the range [4, 127]. - probability pos_special[FULL_DISTANCES - END_POS_MODEL_INDEX]; + probability pos_special[FULL_DISTANCES - DIST_MODEL_END]; /// Probability tree for the lowest four bits of a match distance /// that is equal to or greater than 128. - probability pos_align[ALIGN_TABLE_SIZE]; + probability pos_align[ALIGN_SIZE]; /// Length of a normal match lzma_length_decoder match_len_decoder; @@ -245,8 +245,8 @@ struct lzma_coder_s { SEQ_LITERAL_WRITE, SEQ_IS_REP, seq_len(SEQ_MATCH_LEN), - seq_6(SEQ_POS_SLOT), - SEQ_POS_MODEL, + seq_6(SEQ_DIST_SLOT), + SEQ_DIST_MODEL, SEQ_DIRECT, seq_4(SEQ_ALIGN), SEQ_EOPM, @@ -502,28 +502,28 @@ lzma_decode(lzma_coder *restrict coder, lzma_dict *restrict dictptr, // Prepare to decode the highest two bits of the // match distance. - probs = coder->pos_slot[get_len_to_pos_state(len)]; + probs = coder->dist_slot[get_dist_state(len)]; symbol = 1; #ifdef HAVE_SMALL - case SEQ_POS_SLOT: + case SEQ_DIST_SLOT: do { - rc_bit(probs[symbol], , , SEQ_POS_SLOT); - } while (symbol < POS_SLOTS); + rc_bit(probs[symbol], , , SEQ_DIST_SLOT); + } while (symbol < DIST_SLOTS); #else - rc_bit_case(probs[symbol], , , SEQ_POS_SLOT0); - rc_bit_case(probs[symbol], , , SEQ_POS_SLOT1); - rc_bit_case(probs[symbol], , , SEQ_POS_SLOT2); - rc_bit_case(probs[symbol], , , SEQ_POS_SLOT3); - rc_bit_case(probs[symbol], , , SEQ_POS_SLOT4); - rc_bit_case(probs[symbol], , , SEQ_POS_SLOT5); + rc_bit_case(probs[symbol], , , SEQ_DIST_SLOT0); + rc_bit_case(probs[symbol], , , SEQ_DIST_SLOT1); + rc_bit_case(probs[symbol], , , SEQ_DIST_SLOT2); + rc_bit_case(probs[symbol], , , SEQ_DIST_SLOT3); + rc_bit_case(probs[symbol], , , SEQ_DIST_SLOT4); + rc_bit_case(probs[symbol], , , SEQ_DIST_SLOT5); #endif // Get rid of the highest bit that was needed for // indexing of the probability array. - symbol -= POS_SLOTS; + symbol -= DIST_SLOTS; assert(symbol <= 63); - if (symbol < START_POS_MODEL_INDEX) { + if (symbol < DIST_MODEL_START) { // Match distances [0, 3] have only two bits. rep0 = symbol; } else { @@ -533,7 +533,7 @@ lzma_decode(lzma_coder *restrict coder, lzma_dict *restrict dictptr, assert(limit >= 1 && limit <= 30); rep0 = 2 + (symbol & 1); - if (symbol < END_POS_MODEL_INDEX) { + if (symbol < DIST_MODEL_END) { // Prepare to decode the low bits for // a distance of [4, 127]. assert(limit <= 5); @@ -553,12 +553,12 @@ lzma_decode(lzma_coder *restrict coder, lzma_dict *restrict dictptr, - symbol - 1; symbol = 1; offset = 0; - case SEQ_POS_MODEL: + case SEQ_DIST_MODEL: #ifdef HAVE_SMALL do { rc_bit(probs[symbol], , rep0 += 1 << offset, - SEQ_POS_MODEL); + SEQ_DIST_MODEL); } while (++offset < limit); #else switch (limit) { @@ -566,25 +566,25 @@ lzma_decode(lzma_coder *restrict coder, lzma_dict *restrict dictptr, assert(offset == 0); rc_bit(probs[symbol], , rep0 += 1, - SEQ_POS_MODEL); + SEQ_DIST_MODEL); ++offset; --limit; case 4: rc_bit(probs[symbol], , rep0 += 1 << offset, - SEQ_POS_MODEL); + SEQ_DIST_MODEL); ++offset; --limit; case 3: rc_bit(probs[symbol], , rep0 += 1 << offset, - SEQ_POS_MODEL); + SEQ_DIST_MODEL); ++offset; --limit; case 2: rc_bit(probs[symbol], , rep0 += 1 << offset, - SEQ_POS_MODEL); + SEQ_DIST_MODEL); ++offset; --limit; case 1: @@ -596,7 +596,7 @@ lzma_decode(lzma_coder *restrict coder, lzma_dict *restrict dictptr, // "symbol". rc_bit_last(probs[symbol], , rep0 += 1 << offset, - SEQ_POS_MODEL); + SEQ_DIST_MODEL); } #endif } else { @@ -637,7 +637,7 @@ lzma_decode(lzma_coder *restrict coder, lzma_dict *restrict dictptr, rc_bit(coder->pos_align[symbol], , rep0 += 4, SEQ_ALIGN2); case SEQ_ALIGN3: - // Like in SEQ_POS_MODEL, we don't + // Like in SEQ_DIST_MODEL, we don't // need "symbol" for anything else // than indexing the probability array. rc_bit_last(coder->pos_align[symbol], , @@ -891,10 +891,10 @@ lzma_decoder_reset(lzma_coder *coder, const void *opt) bit_reset(coder->is_rep2[i]); } - for (uint32_t i = 0; i < LEN_TO_POS_STATES; ++i) - bittree_reset(coder->pos_slot[i], POS_SLOT_BITS); + for (uint32_t i = 0; i < DIST_STATES; ++i) + bittree_reset(coder->dist_slot[i], DIST_SLOT_BITS); - for (uint32_t i = 0; i < FULL_DISTANCES - END_POS_MODEL_INDEX; ++i) + for (uint32_t i = 0; i < FULL_DISTANCES - DIST_MODEL_END; ++i) bit_reset(coder->pos_special[i]); bittree_reset(coder->pos_align, ALIGN_BITS); diff --git a/src/liblzma/lzma/lzma_encoder.c b/src/liblzma/lzma/lzma_encoder.c index 0b9ee9e..0f91653 100644 --- a/src/liblzma/lzma/lzma_encoder.c +++ b/src/liblzma/lzma/lzma_encoder.c @@ -148,28 +148,28 @@ match(lzma_coder *coder, const uint32_t pos_state, length(&coder->rc, &coder->match_len_encoder, pos_state, len, coder->fast_mode); - const uint32_t pos_slot = get_pos_slot(distance); - const uint32_t len_to_pos_state = get_len_to_pos_state(len); - rc_bittree(&coder->rc, coder->pos_slot[len_to_pos_state], - POS_SLOT_BITS, pos_slot); - - if (pos_slot >= START_POS_MODEL_INDEX) { - const uint32_t footer_bits = (pos_slot >> 1) - 1; - const uint32_t base = (2 | (pos_slot & 1)) << footer_bits; - const uint32_t pos_reduced = distance - base; - - if (pos_slot < END_POS_MODEL_INDEX) { - // Careful here: base - pos_slot - 1 can be -1, but + const uint32_t dist_slot = get_dist_slot(distance); + const uint32_t dist_state = get_dist_state(len); + rc_bittree(&coder->rc, coder->dist_slot[dist_state], + DIST_SLOT_BITS, dist_slot); + + if (dist_slot >= DIST_MODEL_START) { + const uint32_t footer_bits = (dist_slot >> 1) - 1; + const uint32_t base = (2 | (dist_slot & 1)) << footer_bits; + const uint32_t dist_reduced = distance - base; + + if (dist_slot < DIST_MODEL_END) { + // Careful here: base - dist_slot - 1 can be -1, but // rc_bittree_reverse starts at probs[1], not probs[0]. rc_bittree_reverse(&coder->rc, - coder->pos_special + base - pos_slot - 1, - footer_bits, pos_reduced); + coder->dist_special + base - dist_slot - 1, + footer_bits, dist_reduced); } else { - rc_direct(&coder->rc, pos_reduced >> ALIGN_BITS, + rc_direct(&coder->rc, dist_reduced >> ALIGN_BITS, footer_bits - ALIGN_BITS); rc_bittree_reverse( - &coder->rc, coder->pos_align, - ALIGN_BITS, pos_reduced & ALIGN_MASK); + &coder->rc, coder->dist_align, + ALIGN_BITS, dist_reduced & ALIGN_MASK); ++coder->align_price_count; } } @@ -247,7 +247,7 @@ encode_symbol(lzma_coder *coder, lzma_mf *mf, rc_bit(&coder->rc, &coder->is_match[coder->state][pos_state], 1); - if (back < REP_DISTANCES) { + if (back < REPS) { // It's a repeated match i.e. the same distance // has been used earlier. rc_bit(&coder->rc, &coder->is_rep[coder->state], 1); @@ -255,7 +255,7 @@ encode_symbol(lzma_coder *coder, lzma_mf *mf, } else { // Normal match rc_bit(&coder->rc, &coder->is_rep[coder->state], 0); - match(coder, pos_state, back - REP_DISTANCES, len); + match(coder, pos_state, back - REPS, len); } } @@ -353,9 +353,9 @@ lzma_lzma_encode(lzma_coder *restrict coder, lzma_mf *restrict mf, // Get optimal match (repeat position and length). // Value ranges for pos: - // - [0, REP_DISTANCES): repeated match - // - [REP_DISTANCES, UINT32_MAX): - // match at (pos - REP_DISTANCES) + // - [0, REPS): repeated match + // - [REPS, UINT32_MAX): + // match at (pos - REPS) // - UINT32_MAX: not a match but a literal // Value ranges for len: // - [MATCH_LEN_MIN, MATCH_LEN_MAX] @@ -487,7 +487,7 @@ lzma_lzma_encoder_reset(lzma_coder *coder, const lzma_options_lzma *options) // State coder->state = STATE_LIT_LIT; - for (size_t i = 0; i < REP_DISTANCES; ++i) + for (size_t i = 0; i < REPS; ++i) coder->reps[i] = 0; literal_init(coder->literal, options->lc, options->lp); @@ -505,14 +505,14 @@ lzma_lzma_encoder_reset(lzma_coder *coder, const lzma_options_lzma *options) bit_reset(coder->is_rep2[i]); } - for (size_t i = 0; i < FULL_DISTANCES - END_POS_MODEL_INDEX; ++i) - bit_reset(coder->pos_special[i]); + for (size_t i = 0; i < FULL_DISTANCES - DIST_MODEL_END; ++i) + bit_reset(coder->dist_special[i]); // Bit tree encoders - for (size_t i = 0; i < LEN_TO_POS_STATES; ++i) - bittree_reset(coder->pos_slot[i], POS_SLOT_BITS); + for (size_t i = 0; i < DIST_STATES; ++i) + bittree_reset(coder->dist_slot[i], DIST_SLOT_BITS); - bittree_reset(coder->pos_align, ALIGN_BITS); + bittree_reset(coder->dist_align, ALIGN_BITS); // Length encoders length_encoder_reset(&coder->match_len_encoder, diff --git a/src/liblzma/lzma/lzma_encoder_optimum_fast.c b/src/liblzma/lzma/lzma_encoder_optimum_fast.c index f835f69..92bbdf7 100644 --- a/src/liblzma/lzma/lzma_encoder_optimum_fast.c +++ b/src/liblzma/lzma/lzma_encoder_optimum_fast.c @@ -46,7 +46,7 @@ lzma_lzma_optimum_fast(lzma_coder *restrict coder, lzma_mf *restrict mf, uint32_t rep_len = 0; uint32_t rep_index = 0; - for (uint32_t i = 0; i < REP_DISTANCES; ++i) { + for (uint32_t i = 0; i < REPS; ++i) { // Pointer to the beginning of the match candidate const uint8_t *const buf_back = buf - coder->reps[i] - 1; @@ -79,8 +79,7 @@ lzma_lzma_optimum_fast(lzma_coder *restrict coder, lzma_mf *restrict mf, // We didn't find a long enough repeated match. Encode it as a normal // match if the match length is at least nice_len. if (len_main >= nice_len) { - *back_res = coder->matches[matches_count - 1].dist - + REP_DISTANCES; + *back_res = coder->matches[matches_count - 1].dist + REPS; *len_res = len_main; mf_skip(mf, len_main - 1); return; @@ -155,7 +154,7 @@ lzma_lzma_optimum_fast(lzma_coder *restrict coder, lzma_mf *restrict mf, const uint32_t limit = len_main - 1; - for (uint32_t i = 0; i < REP_DISTANCES; ++i) { + for (uint32_t i = 0; i < REPS; ++i) { const uint8_t *const buf_back = buf - coder->reps[i] - 1; if (not_equal_16(buf, buf_back)) @@ -172,7 +171,7 @@ lzma_lzma_optimum_fast(lzma_coder *restrict coder, lzma_mf *restrict mf, } } - *back_res = back_main + REP_DISTANCES; + *back_res = back_main + REPS; *len_res = len_main; mf_skip(mf, len_main - 2); return; diff --git a/src/liblzma/lzma/lzma_encoder_optimum_normal.c b/src/liblzma/lzma/lzma_encoder_optimum_normal.c index 7e85649..0dd5f73 100644 --- a/src/liblzma/lzma/lzma_encoder_optimum_normal.c +++ b/src/liblzma/lzma/lzma_encoder_optimum_normal.c @@ -108,18 +108,18 @@ get_rep_price(const lzma_coder *const coder, const uint32_t rep_index, static inline uint32_t -get_pos_len_price(const lzma_coder *const coder, const uint32_t pos, +get_dist_len_price(const lzma_coder *const coder, const uint32_t dist, const uint32_t len, const uint32_t pos_state) { - const uint32_t len_to_pos_state = get_len_to_pos_state(len); + const uint32_t dist_state = get_dist_state(len); uint32_t price; - if (pos < FULL_DISTANCES) { - price = coder->distances_prices[len_to_pos_state][pos]; + if (dist < FULL_DISTANCES) { + price = coder->dist_prices[dist_state][dist]; } else { - const uint32_t pos_slot = get_pos_slot_2(pos); - price = coder->pos_slot_prices[len_to_pos_state][pos_slot] - + coder->align_prices[pos & ALIGN_MASK]; + const uint32_t dist_slot = get_dist_slot_2(dist); + price = coder->dist_slot_prices[dist_state][dist_slot] + + coder->align_prices[dist & ALIGN_MASK]; } price += get_len_price(&coder->match_len_encoder, len, pos_state); @@ -129,55 +129,53 @@ get_pos_len_price(const lzma_coder *const coder, const uint32_t pos, static void -fill_distances_prices(lzma_coder *coder) +fill_dist_prices(lzma_coder *coder) { - for (uint32_t len_to_pos_state = 0; - len_to_pos_state < LEN_TO_POS_STATES; - ++len_to_pos_state) { + for (uint32_t dist_state = 0; dist_state < DIST_STATES; ++dist_state) { - uint32_t *const pos_slot_prices - = coder->pos_slot_prices[len_to_pos_state]; + uint32_t *const dist_slot_prices + = coder->dist_slot_prices[dist_state]; - // Price to encode the pos_slot. - for (uint32_t pos_slot = 0; - pos_slot < coder->dist_table_size; ++pos_slot) - pos_slot_prices[pos_slot] = rc_bittree_price( - coder->pos_slot[len_to_pos_state], - POS_SLOT_BITS, pos_slot); + // Price to encode the dist_slot. + for (uint32_t dist_slot = 0; + dist_slot < coder->dist_table_size; ++dist_slot) + dist_slot_prices[dist_slot] = rc_bittree_price( + coder->dist_slot[dist_state], + DIST_SLOT_BITS, dist_slot); // For matches with distance >= FULL_DISTANCES, add the price // of the direct bits part of the match distance. (Align bits // are handled by fill_align_prices()). - for (uint32_t pos_slot = END_POS_MODEL_INDEX; - pos_slot < coder->dist_table_size; ++pos_slot) - pos_slot_prices[pos_slot] += rc_direct_price( - ((pos_slot >> 1) - 1) - ALIGN_BITS); + for (uint32_t dist_slot = DIST_MODEL_END; + dist_slot < coder->dist_table_size; + ++dist_slot) + dist_slot_prices[dist_slot] += rc_direct_price( + ((dist_slot >> 1) - 1) - ALIGN_BITS); // Distances in the range [0, 3] are fully encoded with - // pos_slot, so they are used for coder->distances_prices + // dist_slot, so they are used for coder->dist_prices // as is. - for (uint32_t i = 0; i < START_POS_MODEL_INDEX; ++i) - coder->distances_prices[len_to_pos_state][i] - = pos_slot_prices[i]; + for (uint32_t i = 0; i < DIST_MODEL_START; ++i) + coder->dist_prices[dist_state][i] + = dist_slot_prices[i]; } - // Distances in the range [4, 127] depend on pos_slot and pos_special. - // We do this in a loop separate from the above loop to avoid - // redundant calls to get_pos_slot(). - 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; + // Distances in the range [4, 127] depend on dist_slot and + // dist_special. We do this in a loop separate from the above + // loop to avoid redundant calls to get_dist_slot(). + for (uint32_t i = DIST_MODEL_START; i < FULL_DISTANCES; ++i) { + const uint32_t dist_slot = get_dist_slot(i); + const uint32_t footer_bits = ((dist_slot >> 1) - 1); + const uint32_t base = (2 | (dist_slot & 1)) << footer_bits; const uint32_t price = rc_bittree_reverse_price( - coder->pos_special + base - pos_slot - 1, + coder->dist_special + base - dist_slot - 1, footer_bits, i - base); - for (uint32_t len_to_pos_state = 0; - len_to_pos_state < LEN_TO_POS_STATES; - ++len_to_pos_state) - coder->distances_prices[len_to_pos_state][i] - = price + coder->pos_slot_prices[ - len_to_pos_state][pos_slot]; + for (uint32_t dist_state = 0; dist_state < DIST_STATES; + ++dist_state) + coder->dist_prices[dist_state][i] + = price + coder->dist_slot_prices[ + dist_state][dist_slot]; } coder->match_price_count = 0; @@ -188,9 +186,9 @@ fill_distances_prices(lzma_coder *coder) static void fill_align_prices(lzma_coder *coder) { - for (uint32_t i = 0; i < ALIGN_TABLE_SIZE; ++i) + for (uint32_t i = 0; i < ALIGN_SIZE; ++i) coder->align_prices[i] = rc_bittree_reverse_price( - coder->pos_align, ALIGN_BITS, i); + coder->dist_align, ALIGN_BITS, i); coder->align_price_count = 0; return; @@ -296,10 +294,10 @@ helper1(lzma_coder *restrict coder, lzma_mf *restrict mf, const uint8_t *const buf = mf_ptr(mf) - 1; - uint32_t rep_lens[REP_DISTANCES]; + uint32_t rep_lens[REPS]; uint32_t rep_max_index = 0; - for (uint32_t i = 0; i < REP_DISTANCES; ++i) { + for (uint32_t i = 0; i < REPS; ++i) { const uint8_t *const buf_back = buf - coder->reps[i] - 1; if (not_equal_16(buf, buf_back)) { @@ -326,8 +324,7 @@ helper1(lzma_coder *restrict coder, lzma_mf *restrict mf, if (len_main >= nice_len) { - *back_res = coder->matches[matches_count - 1].dist - + REP_DISTANCES; + *back_res = coder->matches[matches_count - 1].dist + REPS; *len_res = len_main; mf_skip(mf, len_main - 1); return UINT32_MAX; @@ -381,7 +378,7 @@ helper1(lzma_coder *restrict coder, lzma_mf *restrict mf, coder->opts[1].pos_prev = 0; - for (uint32_t i = 0; i < REP_DISTANCES; ++i) + for (uint32_t i = 0; i < REPS; ++i) coder->opts[0].backs[i] = coder->reps[i]; uint32_t len = len_end; @@ -390,7 +387,7 @@ helper1(lzma_coder *restrict coder, lzma_mf *restrict mf, } while (--len >= 2); - for (uint32_t i = 0; i < REP_DISTANCES; ++i) { + for (uint32_t i = 0; i < REPS; ++i) { uint32_t rep_len = rep_lens[i]; if (rep_len < 2) continue; @@ -426,14 +423,13 @@ helper1(lzma_coder *restrict coder, lzma_mf *restrict mf, for(; ; ++len) { const uint32_t dist = coder->matches[i].dist; const uint32_t cur_and_len_price = normal_match_price - + get_pos_len_price(coder, + + get_dist_len_price(coder, dist, len, pos_state); if (cur_and_len_price < coder->opts[len].price) { coder->opts[len].price = cur_and_len_price; coder->opts[len].pos_prev = 0; - coder->opts[len].back_prev - = dist + REP_DISTANCES; + coder->opts[len].back_prev = dist + REPS; coder->opts[len].prev_1_is_literal = false; } @@ -463,7 +459,7 @@ helper2(lzma_coder *coder, uint32_t *reps, const uint8_t *buf, if (coder->opts[cur].prev_2) { state = coder->opts[coder->opts[cur].pos_prev_2].state; - if (coder->opts[cur].back_prev_2 < REP_DISTANCES) + if (coder->opts[cur].back_prev_2 < REPS) update_long_rep(state); else update_match(state); @@ -492,33 +488,33 @@ helper2(lzma_coder *coder, uint32_t *reps, const uint8_t *buf, update_long_rep(state); } else { pos = coder->opts[cur].back_prev; - if (pos < REP_DISTANCES) + if (pos < REPS) update_long_rep(state); else update_match(state); } - if (pos < REP_DISTANCES) { + if (pos < REPS) { reps[0] = coder->opts[pos_prev].backs[pos]; uint32_t i; for (i = 1; i <= pos; ++i) reps[i] = coder->opts[pos_prev].backs[i - 1]; - for (; i < REP_DISTANCES; ++i) + for (; i < REPS; ++i) reps[i] = coder->opts[pos_prev].backs[i]; } else { - reps[0] = pos - REP_DISTANCES; + reps[0] = pos - REPS; - for (uint32_t i = 1; i < REP_DISTANCES; ++i) + for (uint32_t i = 1; i < REPS; ++i) reps[i] = coder->opts[pos_prev].backs[i - 1]; } } coder->opts[cur].state = state; - for (uint32_t i = 0; i < REP_DISTANCES; ++i) + for (uint32_t i = 0; i < REPS; ++i) coder->opts[cur].backs[i] = reps[i]; const uint32_t cur_price = coder->opts[cur].price; @@ -611,7 +607,7 @@ helper2(lzma_coder *coder, uint32_t *reps, const uint8_t *buf, uint32_t start_len = 2; // speed optimization - for (uint32_t rep_index = 0; rep_index < REP_DISTANCES; ++rep_index) { + for (uint32_t rep_index = 0; rep_index < REPS; ++rep_index) { const uint8_t *const buf_back = buf - reps[rep_index] - 1; if (not_equal_16(buf, buf_back)) continue; @@ -728,14 +724,14 @@ helper2(lzma_coder *coder, uint32_t *reps, const uint8_t *buf, for (uint32_t len_test = start_len; ; ++len_test) { const uint32_t cur_back = coder->matches[i].dist; uint32_t cur_and_len_price = normal_match_price - + get_pos_len_price(coder, + + get_dist_len_price(coder, cur_back, len_test, pos_state); if (cur_and_len_price < coder->opts[cur + len_test].price) { coder->opts[cur + len_test].price = cur_and_len_price; coder->opts[cur + len_test].pos_prev = cur; coder->opts[cur + len_test].back_prev - = cur_back + REP_DISTANCES; + = cur_back + REPS; coder->opts[cur + len_test].prev_1_is_literal = false; } @@ -795,7 +791,7 @@ helper2(lzma_coder *coder, uint32_t *reps, const uint8_t *buf, coder->opts[offset].prev_2 = true; coder->opts[offset].pos_prev_2 = cur; coder->opts[offset].back_prev_2 - = cur_back + REP_DISTANCES; + = cur_back + REPS; } //} } @@ -831,9 +827,9 @@ lzma_lzma_optimum_normal(lzma_coder *restrict coder, lzma_mf *restrict mf, // In liblzma they were moved into this single place. if (mf->read_ahead == 0) { if (coder->match_price_count >= (1 << 7)) - fill_distances_prices(coder); + fill_dist_prices(coder); - if (coder->align_price_count >= ALIGN_TABLE_SIZE) + if (coder->align_price_count >= ALIGN_SIZE) fill_align_prices(coder); } @@ -845,7 +841,7 @@ lzma_lzma_optimum_normal(lzma_coder *restrict coder, lzma_mf *restrict mf, if (len_end == UINT32_MAX) return; - uint32_t reps[REP_DISTANCES]; + uint32_t reps[REPS]; memcpy(reps, coder->reps, sizeof(reps)); uint32_t cur; diff --git a/src/liblzma/lzma/lzma_encoder_private.h b/src/liblzma/lzma/lzma_encoder_private.h index 6847452..2f62d6c 100644 --- a/src/liblzma/lzma/lzma_encoder_private.h +++ b/src/liblzma/lzma/lzma_encoder_private.h @@ -64,7 +64,7 @@ typedef struct { uint32_t pos_prev; // pos_next; uint32_t back_prev; - uint32_t backs[REP_DISTANCES]; + uint32_t backs[REPS]; } lzma_optimal; @@ -77,7 +77,7 @@ struct lzma_coder_s { lzma_lzma_state state; /// The four most recent match distances - uint32_t reps[REP_DISTANCES]; + uint32_t reps[REPS]; /// Array of match candidates lzma_match matches[MATCH_LEN_MAX + 1]; @@ -112,9 +112,9 @@ struct lzma_coder_s { probability is_rep1[STATES]; probability is_rep2[STATES]; probability is_rep0_long[STATES][POS_STATES_MAX]; - probability pos_slot[LEN_TO_POS_STATES][POS_SLOTS]; - probability pos_special[FULL_DISTANCES - END_POS_MODEL_INDEX]; - probability pos_align[ALIGN_TABLE_SIZE]; + probability dist_slot[DIST_STATES][DIST_SLOTS]; + probability dist_special[FULL_DISTANCES - DIST_MODEL_END]; + probability dist_align[ALIGN_SIZE]; // These are the same as in lzma_decoder.c except that the encoders // include also price tables. @@ -122,12 +122,12 @@ struct lzma_coder_s { lzma_length_encoder rep_len_encoder; // Price tables - uint32_t pos_slot_prices[LEN_TO_POS_STATES][POS_SLOTS]; - uint32_t distances_prices[LEN_TO_POS_STATES][FULL_DISTANCES]; + uint32_t dist_slot_prices[DIST_STATES][DIST_SLOTS]; + uint32_t dist_prices[DIST_STATES][FULL_DISTANCES]; uint32_t dist_table_size; uint32_t match_price_count; - uint32_t align_prices[ALIGN_TABLE_SIZE]; + uint32_t align_prices[ALIGN_SIZE]; uint32_t align_price_count; // Optimal -- 2.39.2