Move scan_start check, based on Cloudflare commit

5f1bd2b72e5966aa8a4f942e6e8050a050161cf9
zlib-ng · Oct 22, 2019 · cdbc900 · cdbc900
1 parent 4c59062
commit cdbc900
Showing 1 changed file with 2 additions and 4 deletions.
diff --git a/match_p.h b/match_p.h
@@ -432,7 +432,8 @@ static inline unsigned longest_match(deflate_state *const s, IPos cur_match) {
         int cont = 1;
         do {
             match = window + cur_match;
-            if (likely(memcmp(match+best_len-1, &scan_end, sizeof(scan_end)) != 0)) {
+            if (likely(memcmp(match+best_len-1, &scan_end, sizeof(scan_end)) != 0
+                || memcmp(match, &scan_start, sizeof(scan_start)) != 0)) {
                 if ((cur_match = prev[cur_match & wmask]) > limit
                     && --chain_length != 0) {
                     continue;
@@ -446,9 +447,6 @@ static inline unsigned longest_match(deflate_state *const s, IPos cur_match) {
         if (!cont)
             break;
 
-        if (memcmp(match, &scan_start, sizeof(scan_start)) != 0)
-            continue;
-
         /* It is not necessary to compare scan[2] and match[2] since they are
          * always equal when the other bytes match, given that the hash keys
          * are equal and that HASH_BITS >= 8. Compare 2 bytes at a time at