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Merge 1a7549b1ee45176ea040ca3aa1d4ac50cc82c469 into 5a82f71ed1dfc0bec044d9702463dbdf84ea3b71

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Xin Li 2025-03-13 13:34:27 +01:00 committed by GitHub
commit 1de84ff758
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1 changed files with 17 additions and 12 deletions
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29
deflate.c
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@ -152,15 +152,15 @@ local const config configuration_table[10] = {
* the last MIN_MATCH-1 bytes of the input file).
*/
#ifdef FASTEST
#define INSERT_STRING(s, str, match_head) \
(UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
match_head = s->head[s->ins_h], \
s->head[s->ins_h] = (Pos)(str))
#define INSERT_STRING(s, h, str, match_head) \
(UPDATE_HASH(s, h, s->window[(str) + (MIN_MATCH-1)]), \
match_head = s->head[h], \
s->head[h] = (Pos)(str))
#else
#define INSERT_STRING(s, str, match_head) \
(UPDATE_HASH(s, s->ins_h, s->window[(str) + (MIN_MATCH-1)]), \
match_head = s->prev[(str) & s->w_mask] = s->head[s->ins_h], \
s->head[s->ins_h] = (Pos)(str))
#define INSERT_STRING(s, h, str, match_head) \
(UPDATE_HASH(s, h, s->window[(str) + (MIN_MATCH-1)]), \
match_head = s->prev[(str) & s->w_mask] = s->head[h], \
s->head[h] = (Pos)(str))
#endif
/* ===========================================================================
@ -1844,7 +1844,7 @@ local block_state deflate_fast(deflate_state *s, int flush) {
*/
hash_head = NIL;
if (s->lookahead >= MIN_MATCH) {
INSERT_STRING(s, s->strstart, hash_head);
INSERT_STRING(s, s->ins_h, s->strstart, hash_head);
}
/* Find the longest match, discarding those <= prev_length.
@ -1872,14 +1872,16 @@ local block_state deflate_fast(deflate_state *s, int flush) {
#ifndef FASTEST
if (s->match_length <= s->max_insert_length &&
s->lookahead >= MIN_MATCH) {
uInt t_ins_h = s->ins_h;
s->match_length--; /* string at strstart already in table */
do {
s->strstart++;
INSERT_STRING(s, s->strstart, hash_head);
INSERT_STRING(s, t_ins_h, s->strstart, hash_head);
/* strstart never exceeds WSIZE-MAX_MATCH, so there are
* always MIN_MATCH bytes ahead.
*/
} while (--s->match_length != 0);
s->ins_h = t_ins_h;
s->strstart++;
} else
#endif
@ -1944,7 +1946,7 @@ local block_state deflate_slow(deflate_state *s, int flush) {
*/
hash_head = NIL;
if (s->lookahead >= MIN_MATCH) {
INSERT_STRING(s, s->strstart, hash_head);
INSERT_STRING(s, s->ins_h, s->strstart, hash_head);
}
/* Find the longest match, discarding those <= prev_length.
@ -1979,6 +1981,7 @@ local block_state deflate_slow(deflate_state *s, int flush) {
*/
if (s->prev_length >= MIN_MATCH && s->match_length <= s->prev_length) {
uInt max_insert = s->strstart + s->lookahead - MIN_MATCH;
uInt t_ins_h;
/* Do not insert strings in hash table beyond this. */
check_match(s, s->strstart - 1, s->prev_match, s->prev_length);
@ -1993,11 +1996,13 @@ local block_state deflate_slow(deflate_state *s, int flush) {
*/
s->lookahead -= s->prev_length - 1;
s->prev_length -= 2;
t_ins_h = s->ins_h;
do {
if (++s->strstart <= max_insert) {
INSERT_STRING(s, s->strstart, hash_head);
INSERT_STRING(s, t_ins_h, s->strstart, hash_head);
}
} while (--s->prev_length != 0);
s->ins_h = t_ins_h;
s->match_available = 0;
s->match_length = MIN_MATCH-1;
s->strstart++;