diff options
Diffstat (limited to 'src/backend/regex')
| -rw-r--r-- | src/backend/regex/regc_nfa.c | 66 |
1 files changed, 62 insertions, 4 deletions
diff --git a/src/backend/regex/regc_nfa.c b/src/backend/regex/regc_nfa.c index 6d77c59e121..059cf64df07 100644 --- a/src/backend/regex/regc_nfa.c +++ b/src/backend/regex/regc_nfa.c @@ -777,6 +777,10 @@ sortouts_cmp(const void *a, const void *b) * However, if we have a whole lot of arcs to deal with, retail duplicate * checks become too slow. In that case we proceed by sorting and merging * the arc lists, and then we can indeed just update the arcs in-place. + * + * On the other hand, it's also true that this is frequently called with + * a brand-new newState that has no existing in-arcs. In that case, + * de-duplication is unnecessary, so we can just blindly move all the arcs. */ static void moveins(struct nfa *nfa, @@ -785,7 +789,18 @@ moveins(struct nfa *nfa, { assert(oldState != newState); - if (!BULK_ARC_OP_USE_SORT(oldState->nins, newState->nins)) + if (newState->nins == 0) + { + /* No need for de-duplication */ + struct arc *a; + + while ((a = oldState->ins) != NULL) + { + createarc(nfa, a->type, a->co, a->from, newState); + freearc(nfa, a); + } + } + else if (!BULK_ARC_OP_USE_SORT(oldState->nins, newState->nins)) { /* With not too many arcs, just do them one at a time */ struct arc *a; @@ -869,6 +884,11 @@ moveins(struct nfa *nfa, /* * copyins - copy in arcs of a state to another state + * + * The comments for moveins() apply here as well. However, in current + * usage, this is *only* called with brand-new target states, so that + * only the "no need for de-duplication" code path is ever reached. + * We keep the rest #ifdef'd out in case it's needed in the future. */ static void copyins(struct nfa *nfa, @@ -876,8 +896,18 @@ copyins(struct nfa *nfa, struct state *newState) { assert(oldState != newState); + assert(newState->nins == 0); /* see comment above */ + + if (newState->nins == 0) + { + /* No need for de-duplication */ + struct arc *a; - if (!BULK_ARC_OP_USE_SORT(oldState->nins, newState->nins)) + for (a = oldState->ins; a != NULL; a = a->inchain) + createarc(nfa, a->type, a->co, a->from, newState); + } +#ifdef NOT_USED /* see comment above */ + else if (!BULK_ARC_OP_USE_SORT(oldState->nins, newState->nins)) { /* With not too many arcs, just do them one at a time */ struct arc *a; @@ -944,6 +974,7 @@ copyins(struct nfa *nfa, createarc(nfa, a->type, a->co, a->from, newState); } } +#endif /* NOT_USED */ } /* @@ -1058,7 +1089,18 @@ moveouts(struct nfa *nfa, { assert(oldState != newState); - if (!BULK_ARC_OP_USE_SORT(oldState->nouts, newState->nouts)) + if (newState->nouts == 0) + { + /* No need for de-duplication */ + struct arc *a; + + while ((a = oldState->outs) != NULL) + { + createarc(nfa, a->type, a->co, newState, a->to); + freearc(nfa, a); + } + } + else if (!BULK_ARC_OP_USE_SORT(oldState->nouts, newState->nouts)) { /* With not too many arcs, just do them one at a time */ struct arc *a; @@ -1142,6 +1184,8 @@ moveouts(struct nfa *nfa, /* * copyouts - copy out arcs of a state to another state + * + * See comments for copyins() */ static void copyouts(struct nfa *nfa, @@ -1149,8 +1193,18 @@ copyouts(struct nfa *nfa, struct state *newState) { assert(oldState != newState); + assert(newState->nouts == 0); /* see comment above */ + + if (newState->nouts == 0) + { + /* No need for de-duplication */ + struct arc *a; - if (!BULK_ARC_OP_USE_SORT(oldState->nouts, newState->nouts)) + for (a = oldState->outs; a != NULL; a = a->outchain) + createarc(nfa, a->type, a->co, newState, a->to); + } +#ifdef NOT_USED /* see comment above */ + else if (!BULK_ARC_OP_USE_SORT(oldState->nouts, newState->nouts)) { /* With not too many arcs, just do them one at a time */ struct arc *a; @@ -1217,6 +1271,7 @@ copyouts(struct nfa *nfa, createarc(nfa, a->type, a->co, newState, a->to); } } +#endif /* NOT_USED */ } /* @@ -1975,6 +2030,7 @@ combine(struct nfa *nfa, else if (a->co == RAINBOW) { /* con is incompatible if it's for a pseudocolor */ + /* (this is hypothetical; we make no such constraints today) */ if (nfa->cm->cd[con->co].flags & PSEUDO) return INCOMPATIBLE; /* otherwise, constraint constrains arc to be only its color */ @@ -2001,6 +2057,7 @@ combine(struct nfa *nfa, else if (a->co == RAINBOW) { /* con is incompatible if it's for a pseudocolor */ + /* (this is hypothetical; we make no such constraints today) */ if (nfa->cm->cd[con->co].flags & PSEUDO) return INCOMPATIBLE; /* otherwise, constraint constrains arc to be only its color */ @@ -3562,6 +3619,7 @@ carc_cmp(const void *a, const void *b) return -1; if (aa->to > bb->to) return +1; + /* This is unreached, since there should be no duplicate arcs now: */ return 0; } |