From b37c878548a7ad53d94a2089aa200acab215fa0c Mon Sep 17 00:00:00 2001 From: Norihiro Tanaka Date: Thu, 20 Sep 2018 00:18:11 +0900 Subject: [PATCH] dfa: optimization for state merge dfa.c (merge2): Add new function. (merge_nfa_state): Update caller. --- lib/dfa.c | 18 ++++++++++++++++-- 1 files changed, 16 insertions(+), 2 deletions(-) diff --git a/lib/dfa.c b/lib/dfa.c index 13b2a0b..d04bcbe 100644 --- a/lib/dfa.c +++ b/lib/dfa.c @@ -2102,6 +2102,21 @@ merge (position_set const *s1, position_set const *s2, position_set *m) merge_constrained (s1, s2, -1, m); } +static void +merge2 (position_set *dst, position_set const *src, position_set *m) +{ + if (src->nelem < 4) + { + for (ptrdiff_t i = 0; i < src->nelem; ++i) + insert (src->elems[i], dst); + } + else + { + merge (src, dst, m); + copy (m, dst); + } +} + /* Delete a position from a set. Return the nonzero constraint of the deleted position, or zero if there was no such position. */ static unsigned int @@ -2388,8 +2403,7 @@ merge_nfa_state (struct dfa *d, size_t *queue, ptrdiff_t nqueue, size_t tindex, if (flags[sindex] & OPT_REPEAT) delete (sindex, &follows[sindex]); - merge (&follows[dindex], &follows[sindex], merged); - copy (merged, &follows[dindex]); + merge2 (&follows[dindex], &follows[sindex], merged); /* Mark it as pruned in future. */ follows[tindex].elems[j].constraint = 0; -- 1.7.1