]> wimlib.net Git - wimlib/blobdiff - src/lzms_compress.c
Fix various typos
[wimlib] / src / lzms_compress.c
index caa93130c75ca44f656a1d8464621985d6eb3bd1..e811a87658bda5eea3db465bf5c446f068a6229e 100644 (file)
@@ -173,7 +173,7 @@ struct lzms_item {
 static inline void
 check_that_powers_fit_in_bitfield(void)
 {
-       BUILD_BUG_ON(LZMS_NUM_DELTA_POWER_SYMS > (1 << (31 - DELTA_SOURCE_POWER_SHIFT)));
+       STATIC_ASSERT(LZMS_NUM_DELTA_POWER_SYMS <= (1 << (31 - DELTA_SOURCE_POWER_SHIFT)));
 }
 
 /* A stripped-down version of the adaptive state in LZMS which excludes the
@@ -249,7 +249,7 @@ struct lzms_optimum_node {
         *
         * Note: this adaptive state structure also does not include the
         * probability entries or current Huffman codewords.  Those aren't
-        * maintained per-position and are only updated occassionally.
+        * maintained per-position and are only updated occasionally.
         */
        struct lzms_adaptive_state state;
 } _aligned_attribute(64);
@@ -307,7 +307,8 @@ struct lzms_compressor {
        u32 next_delta_hashes[NUM_POWERS_TO_CONSIDER];
 
        /* The per-byte graph nodes for near-optimal parsing  */
-       struct lzms_optimum_node optimum_nodes[NUM_OPTIM_NODES + MAX_FAST_LENGTH];
+       struct lzms_optimum_node optimum_nodes[NUM_OPTIM_NODES + MAX_FAST_LENGTH +
+                                              1 + MAX_FAST_LENGTH];
 
        /* Table: length => current cost for small match lengths  */
        u32 fast_length_cost_tab[MAX_FAST_LENGTH + 1];
@@ -327,14 +328,7 @@ struct lzms_compressor {
        unsigned lz_rep_states[LZMS_NUM_LZ_REP_DECISIONS];
        unsigned delta_state;
        unsigned delta_rep_states[LZMS_NUM_DELTA_REP_DECISIONS];
-       struct lzms_probability_entry main_probs[LZMS_NUM_MAIN_PROBS];
-       struct lzms_probability_entry match_probs[LZMS_NUM_MATCH_PROBS];
-       struct lzms_probability_entry lz_probs[LZMS_NUM_LZ_PROBS];
-       struct lzms_probability_entry lz_rep_probs[LZMS_NUM_LZ_REP_DECISIONS]
-                                                 [LZMS_NUM_LZ_REP_PROBS];
-       struct lzms_probability_entry delta_probs[LZMS_NUM_DELTA_PROBS];
-       struct lzms_probability_entry delta_rep_probs[LZMS_NUM_DELTA_REP_DECISIONS]
-                                                    [LZMS_NUM_DELTA_REP_PROBS];
+       struct lzms_probabilites probs;
 
        /* Huffman codes  */
 
@@ -586,42 +580,42 @@ static void
 lzms_encode_main_bit(struct lzms_compressor *c, int bit)
 {
        lzms_encode_bit(bit, &c->main_state, LZMS_NUM_MAIN_PROBS,
-                       c->main_probs, &c->rc);
+                       c->probs.main, &c->rc);
 }
 
 static void
 lzms_encode_match_bit(struct lzms_compressor *c, int bit)
 {
        lzms_encode_bit(bit, &c->match_state, LZMS_NUM_MATCH_PROBS,
-                       c->match_probs, &c->rc);
+                       c->probs.match, &c->rc);
 }
 
 static void
 lzms_encode_lz_bit(struct lzms_compressor *c, int bit)
 {
        lzms_encode_bit(bit, &c->lz_state, LZMS_NUM_LZ_PROBS,
-                       c->lz_probs, &c->rc);
+                       c->probs.lz, &c->rc);
 }
 
 static void
 lzms_encode_lz_rep_bit(struct lzms_compressor *c, int bit, int idx)
 {
        lzms_encode_bit(bit, &c->lz_rep_states[idx], LZMS_NUM_LZ_REP_PROBS,
-                       c->lz_rep_probs[idx], &c->rc);
+                       c->probs.lz_rep[idx], &c->rc);
 }
 
 static void
 lzms_encode_delta_bit(struct lzms_compressor *c, int bit)
 {
        lzms_encode_bit(bit, &c->delta_state, LZMS_NUM_DELTA_PROBS,
-                       c->delta_probs, &c->rc);
+                       c->probs.delta, &c->rc);
 }
 
 static void
 lzms_encode_delta_rep_bit(struct lzms_compressor *c, int bit, int idx)
 {
        lzms_encode_bit(bit, &c->delta_rep_states[idx], LZMS_NUM_DELTA_REP_PROBS,
-                       c->delta_rep_probs[idx], &c->rc);
+                       c->probs.delta_rep[idx], &c->rc);
 }
 
 /******************************************************************************
@@ -946,7 +940,7 @@ lzms_encode_item_list(struct lzms_compressor *c,
 }
 
 /******************************************************************************
- *                             Cost evalution                                 *
+ *                             Cost evaluation                                *
  ******************************************************************************/
 
 /*
@@ -981,7 +975,7 @@ static inline void
 check_cost_shift(void)
 {
        /* lzms_bit_costs is hard-coded to the current COST_SHIFT.  */
-       BUILD_BUG_ON(COST_SHIFT != 6);
+       STATIC_ASSERT(COST_SHIFT == 6);
 }
 
 #if 0
@@ -1022,7 +1016,7 @@ lzms_bit_1_cost(unsigned state, const struct lzms_probability_entry *probs)
 static inline u32
 lzms_literal_cost(struct lzms_compressor *c, unsigned main_state, unsigned literal)
 {
-       return lzms_bit_0_cost(main_state, c->main_probs) +
+       return lzms_bit_0_cost(main_state, c->probs.main) +
                ((u32)c->literal_lens[literal] << COST_SHIFT);
 }
 
@@ -1126,7 +1120,7 @@ lzms_update_lru_queues(struct lzms_adaptive_state *state)
 static inline void
 lzms_update_state(u8 *state_p, int bit, unsigned num_states)
 {
-       *state_p = ((*state_p << 1) | bit) % num_states;
+       *state_p = ((*state_p << 1) | bit) & (num_states - 1);
 }
 
 static inline void
@@ -1186,7 +1180,7 @@ static void
 lzms_init_delta_matchfinder(struct lzms_compressor *c)
 {
        /* Set all entries to use an invalid power, which will never match.  */
-       BUILD_BUG_ON(NUM_POWERS_TO_CONSIDER >= (1 << (32 - DELTA_SOURCE_POWER_SHIFT)));
+       STATIC_ASSERT(NUM_POWERS_TO_CONSIDER < (1 << (32 - DELTA_SOURCE_POWER_SHIFT)));
        memset(c->delta_hash_table, 0xFF, sizeof(c->delta_hash_table));
 
        /* Initialize the next hash code for each power.  We can just use zeroes
@@ -1201,7 +1195,7 @@ lzms_init_delta_matchfinder(struct lzms_compressor *c)
  * delta context with the specified @span.
  */
 static inline u32
-lzms_delta_hash(const u8 *p, u32 span)
+lzms_delta_hash(const u8 *p, const u32 pos, u32 span)
 {
        /* A delta match has a certain span and an offset that is a multiple of
         * that span.  To reduce wasted space we use a single combined hash
@@ -1209,11 +1203,11 @@ lzms_delta_hash(const u8 *p, u32 span)
         * include in the hash code computation the span and the low-order bits
         * of the current position.  */
 
-       BUILD_BUG_ON(NBYTES_HASHED_FOR_DELTA != 3);
+       STATIC_ASSERT(NBYTES_HASHED_FOR_DELTA == 3);
        u8 d0 = *(p + 0) - *(p + 0 - span);
        u8 d1 = *(p + 1) - *(p + 1 - span);
        u8 d2 = *(p + 2) - *(p + 2 - span);
-       u32 v = ((span + ((u32)(uintptr_t)p & (span - 1))) << 24) |
+       u32 v = ((span + (pos & (span - 1))) << 24) |
                ((u32)d2 << 16) | ((u32)d1 << 8) | d0;
        return lz_hash(v, DELTA_HASH_ORDER);
 }
@@ -1249,12 +1243,12 @@ lzms_delta_matchfinder_skip_bytes(struct lzms_compressor *c,
                        const u32 span = (u32)1 << power;
                        if (unlikely(pos < span))
                                continue;
-                       const u32 next_hash = lzms_delta_hash(in_next + 1, span);
+                       const u32 next_hash = lzms_delta_hash(in_next + 1, pos + 1, span);
                        const u32 hash = c->next_delta_hashes[power];
                        c->delta_hash_table[hash] =
                                (power << DELTA_SOURCE_POWER_SHIFT) | pos;
                        c->next_delta_hashes[power] = next_hash;
-                       prefetch(&c->delta_hash_table[next_hash]);
+                       prefetchw(&c->delta_hash_table[next_hash]);
                }
        } while (in_next++, pos++, --count);
 }
@@ -1286,10 +1280,10 @@ lzms_skip_bytes(struct lzms_compressor *c, u32 count, const u8 *in_next)
  * can be reached using a match or literal from the current position.  This is
  * essentially Dijkstra's algorithm in disguise: the graph nodes are positions,
  * the graph edges are possible matches/literals to code, and the cost of each
- * edge is the estimated number of bits that will be required to output the
- * corresponding match or literal.  But one difference is that we actually
- * compute the lowest-cost path in pieces, where each piece is terminated when
- * there are no choices to be made.
+ * edge is the estimated number of bits (scaled up by COST_SHIFT) that will be
+ * required to output the corresponding match or literal.  But one difference is
+ * that we actually compute the lowest-cost path in pieces, where each piece is
+ * terminated when there are no choices to be made.
  *
  * The costs of literals and matches are estimated using the range encoder
  * states and the semi-adaptive Huffman codes.  Except for range encoding
@@ -1379,19 +1373,19 @@ begin:
 
                                u32 base_cost = cur_node->cost +
                                                lzms_bit_1_cost(cur_node->state.main_state,
-                                                               c->main_probs) +
+                                                               c->probs.main) +
                                                lzms_bit_0_cost(cur_node->state.match_state,
-                                                               c->match_probs) +
+                                                               c->probs.match) +
                                                lzms_bit_1_cost(cur_node->state.lz_state,
-                                                               c->lz_probs);
+                                                               c->probs.lz);
 
                                for (int i = 0; i < rep_idx; i++)
                                        base_cost += lzms_bit_1_cost(cur_node->state.lz_rep_states[i],
-                                                                    c->lz_rep_probs[i]);
+                                                                    c->probs.lz_rep[i]);
 
                                if (rep_idx < LZMS_NUM_LZ_REP_DECISIONS)
                                        base_cost += lzms_bit_0_cost(cur_node->state.lz_rep_states[rep_idx],
-                                                                    c->lz_rep_probs[rep_idx]);
+                                                                    c->probs.lz_rep[rep_idx]);
 
                                u32 len = 2;
                                do {
@@ -1441,10 +1435,10 @@ begin:
                                        main_state = ((main_state << 1) | 0) % LZMS_NUM_MAIN_PROBS;
 
                                        /* add LZ-rep0 cost  */
-                                       cost += lzms_bit_1_cost(main_state, c->main_probs) +
-                                               lzms_bit_0_cost(match_state, c->match_probs) +
-                                               lzms_bit_1_cost(lz_state, c->lz_probs) +
-                                               lzms_bit_0_cost(lz_rep0_state, c->lz_rep_probs[0]) +
+                                       cost += lzms_bit_1_cost(main_state, c->probs.main) +
+                                               lzms_bit_0_cost(match_state, c->probs.match) +
+                                               lzms_bit_1_cost(lz_state, c->probs.lz) +
+                                               lzms_bit_0_cost(lz_rep0_state, c->probs.lz_rep[0]) +
                                                lzms_fast_length_cost(c, rep0_len);
 
                                        const u32 total_len = rep_len + 1 + rep0_len;
@@ -1531,19 +1525,19 @@ begin:
 
                                u32 base_cost = cur_node->cost +
                                                lzms_bit_1_cost(cur_node->state.main_state,
-                                                               c->main_probs) +
+                                                               c->probs.main) +
                                                lzms_bit_1_cost(cur_node->state.match_state,
-                                                               c->match_probs) +
+                                                               c->probs.match) +
                                                lzms_bit_1_cost(cur_node->state.delta_state,
-                                                               c->delta_probs);
+                                                               c->probs.delta);
 
                                for (int i = 0; i < rep_idx; i++)
                                        base_cost += lzms_bit_1_cost(cur_node->state.delta_rep_states[i],
-                                                                    c->delta_rep_probs[i]);
+                                                                    c->probs.delta_rep[i]);
 
                                if (rep_idx < LZMS_NUM_DELTA_REP_DECISIONS)
                                        base_cost += lzms_bit_0_cost(cur_node->state.delta_rep_states[rep_idx],
-                                                                    c->delta_rep_probs[rep_idx]);
+                                                                    c->probs.delta_rep[rep_idx]);
 
                                u32 len = 2;
                                do {
@@ -1600,11 +1594,11 @@ begin:
 
                        u32 base_cost = cur_node->cost +
                                        lzms_bit_1_cost(cur_node->state.main_state,
-                                                       c->main_probs) +
+                                                       c->probs.main) +
                                        lzms_bit_0_cost(cur_node->state.match_state,
-                                                       c->match_probs) +
+                                                       c->probs.match) +
                                        lzms_bit_0_cost(cur_node->state.lz_state,
-                                                       c->lz_probs);
+                                                       c->probs.lz);
 
                        if (c->try_lzmatch_lit_lzrep0 &&
                            likely(in_end - (in_next + c->matches[0].length) >= 3))
@@ -1660,11 +1654,11 @@ begin:
                                        main_state = ((main_state << 1) | 0) % LZMS_NUM_MAIN_PROBS;
 
                                        /* add LZ-rep0 cost  */
-                                       cost += lzms_bit_1_cost(main_state, c->main_probs) +
-                                               lzms_bit_0_cost(match_state, c->match_probs) +
-                                               lzms_bit_1_cost(lz_state, c->lz_probs) +
+                                       cost += lzms_bit_1_cost(main_state, c->probs.main) +
+                                               lzms_bit_0_cost(match_state, c->probs.match) +
+                                               lzms_bit_1_cost(lz_state, c->probs.lz) +
                                                lzms_bit_0_cost(cur_node->state.lz_rep_states[0],
-                                                               c->lz_rep_probs[0]) +
+                                                               c->probs.lz_rep[0]) +
                                                lzms_fast_length_cost(c, rep0_len);
 
                                        const u32 total_len = len + 1 + rep0_len;
@@ -1718,7 +1712,7 @@ begin:
                        const u32 pos = in_next - c->in_buffer;
 
                        /* Consider each possible power (log2 of span)  */
-                       BUILD_BUG_ON(NUM_POWERS_TO_CONSIDER > LZMS_NUM_DELTA_POWER_SYMS);
+                       STATIC_ASSERT(NUM_POWERS_TO_CONSIDER <= LZMS_NUM_DELTA_POWER_SYMS);
                        for (u32 power = 0; power < NUM_POWERS_TO_CONSIDER; power++) {
 
                                const u32 span = (u32)1 << power;
@@ -1726,13 +1720,13 @@ begin:
                                if (unlikely(pos < span))
                                        continue;
 
-                               const u32 next_hash = lzms_delta_hash(in_next + 1, span);
+                               const u32 next_hash = lzms_delta_hash(in_next + 1, pos + 1, span);
                                const u32 hash = c->next_delta_hashes[power];
                                const u32 cur_match = c->delta_hash_table[hash];
 
                                c->delta_hash_table[hash] = (power << DELTA_SOURCE_POWER_SHIFT) | pos;
                                c->next_delta_hashes[power] = next_hash;
-                               prefetch(&c->delta_hash_table[next_hash]);
+                               prefetchw(&c->delta_hash_table[next_hash]);
 
                                if (power != cur_match >> DELTA_SOURCE_POWER_SHIFT)
                                        continue;
@@ -1747,7 +1741,7 @@ begin:
 
                                /* Check the first 3 bytes before entering the
                                 * extension loop.  */
-                               BUILD_BUG_ON(NBYTES_HASHED_FOR_DELTA != 3);
+                               STATIC_ASSERT(NBYTES_HASHED_FOR_DELTA == 3);
                                if (((u8)(*(in_next + 0) - *(in_next + 0 - span)) !=
                                     (u8)(*(matchptr + 0) - *(matchptr + 0 - span))) ||
                                    ((u8)(*(in_next + 1) - *(in_next + 1 - span)) !=
@@ -1759,11 +1753,16 @@ begin:
                                /* Extend the delta match to its full length.  */
                                const u32 len = lzms_extend_delta_match(in_next,
                                                                        matchptr,
-                                                                       3,
+                                                                       NBYTES_HASHED_FOR_DELTA,
                                                                        in_end - in_next,
                                                                        span);
 
                                const u32 raw_offset = offset >> power;
+
+                               if (unlikely(raw_offset > DELTA_SOURCE_RAW_OFFSET_MASK -
+                                                         (LZMS_NUM_DELTA_REPS - 1)))
+                                       continue;
+
                                const u32 pair = (power << DELTA_SOURCE_POWER_SHIFT) |
                                                 raw_offset;
                                const u32 source = DELTA_SOURCE_TAG |
@@ -1794,11 +1793,11 @@ begin:
 
                                u32 base_cost = cur_node->cost +
                                                lzms_bit_1_cost(cur_node->state.main_state,
-                                                               c->main_probs) +
+                                                               c->probs.main) +
                                                lzms_bit_1_cost(cur_node->state.match_state,
-                                                               c->match_probs) +
+                                                               c->probs.match) +
                                                lzms_bit_0_cost(cur_node->state.delta_state,
-                                                               c->delta_probs) +
+                                                               c->probs.delta) +
                                                lzms_delta_source_cost(c, power, raw_offset);
 
                                u32 l = NBYTES_HASHED_FOR_DELTA;
@@ -1852,13 +1851,13 @@ begin:
 
                                /* Add cost of LZ-rep0  */
                                const u32 cost = cur_and_lit_cost +
-                                                lzms_bit_1_cost(main_state, c->main_probs) +
+                                                lzms_bit_1_cost(main_state, c->probs.main) +
                                                 lzms_bit_0_cost(cur_node->state.match_state,
-                                                                c->match_probs) +
+                                                                c->probs.match) +
                                                 lzms_bit_1_cost(cur_node->state.lz_state,
-                                                                c->lz_probs) +
+                                                                c->probs.lz) +
                                                 lzms_bit_0_cost(cur_node->state.lz_rep_states[0],
-                                                                c->lz_rep_probs[0]) +
+                                                                c->probs.lz_rep[0]) +
                                                 lzms_fast_length_cost(c, rep0_len);
 
                                const u32 total_len = 1 + rep0_len;
@@ -1889,7 +1888,7 @@ begin:
                 * Finalize the adaptive state that results from taking this
                 * lowest-cost path.  */
                struct lzms_item item_to_take = cur_node->item;
-               struct lzms_optimum_node *source_node = cur_node - (item_to_take.length);
+               struct lzms_optimum_node *source_node = cur_node - item_to_take.length;
                int next_item_idx = -1;
                for (unsigned i = 0; i < cur_node->num_extra_items; i++) {
                        item_to_take = cur_node->extra_items[i];
@@ -1916,9 +1915,9 @@ begin:
 
                                        if (source >= LZMS_NUM_DELTA_REPS) {
                                                /* Explicit offset delta match  */
-                                               u32 pair = source - (LZMS_NUM_DELTA_REPS - 1);
                                                lzms_update_delta_state(&cur_node->state, 0);
-                                               cur_node->state.upcoming_delta_pair = pair;
+                                               cur_node->state.upcoming_delta_pair =
+                                                       source - (LZMS_NUM_DELTA_REPS - 1);
                                        } else {
                                                /* Repeat offset delta match  */
                                                int rep_idx = source;
@@ -2017,14 +2016,7 @@ lzms_init_states_and_probabilities(struct lzms_compressor *c)
        for (int i = 0; i < LZMS_NUM_DELTA_REP_DECISIONS; i++)
                c->delta_rep_states[i] = 0;
 
-       lzms_init_probability_entries(c->main_probs, LZMS_NUM_MAIN_PROBS);
-       lzms_init_probability_entries(c->match_probs, LZMS_NUM_MATCH_PROBS);
-       lzms_init_probability_entries(c->lz_probs, LZMS_NUM_LZ_PROBS);
-       for (int i = 0; i < LZMS_NUM_LZ_REP_DECISIONS; i++)
-               lzms_init_probability_entries(c->lz_rep_probs[i], LZMS_NUM_LZ_REP_PROBS);
-       lzms_init_probability_entries(c->delta_probs, LZMS_NUM_DELTA_PROBS);
-       for (int i = 0; i < LZMS_NUM_DELTA_REP_DECISIONS; i++)
-               lzms_init_probability_entries(c->delta_rep_probs[i], LZMS_NUM_DELTA_REP_PROBS);
+       lzms_init_probabilities(&c->probs);
 }
 
 static void
@@ -2174,8 +2166,8 @@ oom0:
 }
 
 static size_t
-lzms_compress(const void *in, size_t in_nbytes,
-             void *out, size_t out_nbytes_avail, void *_c)
+lzms_compress(const void *restrict in, size_t in_nbytes,
+             void *restrict out, size_t out_nbytes_avail, void *restrict _c)
 {
        struct lzms_compressor *c = _c;
        size_t result;