]> wimlib.net Git - wimlib/blobdiff - src/lzms_compress.c
Use 'restrict' on pointer arguments to all compress() and decompress() functions
[wimlib] / src / lzms_compress.c
index 88f39b300a9a16458451de80b5bf8729284c2f76..f438e91cd15156f48e8371f3bf5f1cc6aa044413 100644 (file)
@@ -328,14 +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  */
 
@@ -587,42 +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);
 }
 
 /******************************************************************************
@@ -1023,7 +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);
 }
 
@@ -1127,7 +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
@@ -1287,10 +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
@@ -1380,19 +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 {
@@ -1442,10 +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;
@@ -1532,19 +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 {
@@ -1601,11 +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))
@@ -1661,11 +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;
@@ -1760,7 +1753,7 @@ 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);
 
@@ -1800,11 +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;
@@ -1858,13 +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;
@@ -1895,7 +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];
@@ -1922,9 +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;
@@ -2023,14 +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
@@ -2180,8 +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;