diff --git a/src/backend/regex/regc_nfa.c b/src/backend/regex/regc_nfa.c
index 698c3ca4d3ef106058d5ca75440780c5ab005e64..050426d3b406d7ef984e70b956b9eb4eae353659 100644
--- a/src/backend/regex/regc_nfa.c
+++ b/src/backend/regex/regc_nfa.c
@@ -321,6 +321,9 @@ destroystate(struct nfa * nfa,
/*
* newarc - set up a new arc within an NFA
+ *
+ * This function checks to make sure that no duplicate arcs are created.
+ * In general we never want duplicates.
*/
static void
newarc(struct nfa * nfa,
@@ -344,11 +347,40 @@ newarc(struct nfa * nfa,
return;
}
- /* check for duplicates */
- for (a = from->outs; a != NULL; a = a->outchain)
- if (a->to == to && a->co == co && a->type == t)
- return;
+ /* check for duplicate arc, using whichever chain is shorter */
+ if (from->nouts <= to->nins)
+ {
+ for (a = from->outs; a != NULL; a = a->outchain)
+ if (a->to == to && a->co == co && a->type == t)
+ return;
+ }
+ else
+ {
+ for (a = to->ins; a != NULL; a = a->inchain)
+ if (a->from == from && a->co == co && a->type == t)
+ return;
+ }
+
+ /* no dup, so create the arc */
+ createarc(nfa, t, co, from, to);
+}
+/*
+ * createarc - create a new arc within an NFA
+ *
+ * This function must *only* be used after verifying that there is no existing
+ * identical arc (same type/color/from/to).
+ */
+static void
+createarc(struct nfa * nfa,
+ int t,
+ pcolor co,
+ struct state * from,
+ struct state * to)
+{
+ struct arc *a;
+
+ /* the arc is physically allocated within its from-state */
a = allocarc(nfa, from);
if (NISERR())
return;
@@ -360,14 +392,19 @@ newarc(struct nfa * nfa,
a->from = from;
/*
- * Put the new arc on the beginning, not the end, of the chains. Not only
- * is this easier, it has the very useful side effect that deleting the
- * most-recently-added arc is the cheapest case rather than the most
- * expensive one.
+ * Put the new arc on the beginning, not the end, of the chains; it's
+ * simpler here, and freearc() is the same cost either way. See also the
+ * logic in moveins() and its cohorts, as well as fixempties().
*/
a->inchain = to->ins;
+ a->inchainRev = NULL;
+ if (to->ins)
+ to->ins->inchainRev = a;
to->ins = a;
a->outchain = from->outs;
+ a->outchainRev = NULL;
+ if (from->outs)
+ from->outs->outchainRev = a;
from->outs = a;
from->nouts++;
@@ -433,7 +470,7 @@ freearc(struct nfa * nfa,
{
struct state *from = victim->from;
struct state *to = victim->to;
- struct arc *a;
+ struct arc *predecessor;
assert(victim->type != 0);
@@ -443,44 +480,103 @@ freearc(struct nfa * nfa,
/* take it off source's out-chain */
assert(from != NULL);
- assert(from->outs != NULL);
- a = from->outs;
- if (a == victim) /* simple case: first in chain */
+ predecessor = victim->outchainRev;
+ if (predecessor == NULL)
+ {
+ assert(from->outs == victim);
from->outs = victim->outchain;
+ }
else
{
- for (; a != NULL && a->outchain != victim; a = a->outchain)
- continue;
- assert(a != NULL);
- a->outchain = victim->outchain;
+ assert(predecessor->outchain == victim);
+ predecessor->outchain = victim->outchain;
+ }
+ if (victim->outchain != NULL)
+ {
+ assert(victim->outchain->outchainRev == victim);
+ victim->outchain->outchainRev = predecessor;
}
from->nouts--;
/* take it off target's in-chain */
assert(to != NULL);
- assert(to->ins != NULL);
- a = to->ins;
- if (a == victim) /* simple case: first in chain */
+ predecessor = victim->inchainRev;
+ if (predecessor == NULL)
+ {
+ assert(to->ins == victim);
to->ins = victim->inchain;
+ }
else
{
- for (; a != NULL && a->inchain != victim; a = a->inchain)
- continue;
- assert(a != NULL);
- a->inchain = victim->inchain;
+ assert(predecessor->inchain == victim);
+ predecessor->inchain = victim->inchain;
+ }
+ if (victim->inchain != NULL)
+ {
+ assert(victim->inchain->inchainRev == victim);
+ victim->inchain->inchainRev = predecessor;
}
to->nins--;
- /* clean up and place on free list */
+ /* clean up and place on from-state's free list */
victim->type = 0;
victim->from = NULL; /* precautions... */
victim->to = NULL;
victim->inchain = NULL;
+ victim->inchainRev = NULL;
victim->outchain = NULL;
+ victim->outchainRev = NULL;
victim->freechain = from->free;
from->free = victim;
}
+/*
+ * changearctarget - flip an arc to have a different to state
+ *
+ * Caller must have verified that there is no pre-existing duplicate arc.
+ *
+ * Note that because we store arcs in their from state, we can't easily have
+ * a similar changearcsource function.
+ */
+static void
+changearctarget(struct arc * a, struct state * newto)
+{
+ struct state *oldto = a->to;
+ struct arc *predecessor;
+
+ assert(oldto != newto);
+
+ /* take it off old target's in-chain */
+ assert(oldto != NULL);
+ predecessor = a->inchainRev;
+ if (predecessor == NULL)
+ {
+ assert(oldto->ins == a);
+ oldto->ins = a->inchain;
+ }
+ else
+ {
+ assert(predecessor->inchain == a);
+ predecessor->inchain = a->inchain;
+ }
+ if (a->inchain != NULL)
+ {
+ assert(a->inchain->inchainRev == a);
+ a->inchain->inchainRev = predecessor;
+ }
+ oldto->nins--;
+
+ a->to = newto;
+
+ /* prepend it to new target's in-chain */
+ a->inchain = newto->ins;
+ a->inchainRev = NULL;
+ if (newto->ins)
+ newto->ins->inchainRev = a;
+ newto->ins = a;
+ newto->nins++;
+}
+
/*
* hasnonemptyout - Does state have a non-EMPTY out arc?
*/
@@ -560,28 +656,248 @@ cparc(struct nfa * nfa,
newarc(nfa, oa->type, oa->co, from, to);
}
+/*
+ * sortins - sort the in arcs of a state by from/color/type
+ */
+static void
+sortins(struct nfa * nfa,
+ struct state * s)
+{
+ struct arc **sortarray;
+ struct arc *a;
+ int n = s->nins;
+ int i;
+
+ if (n <= 1)
+ return; /* nothing to do */
+ /* make an array of arc pointers ... */
+ sortarray = (struct arc **) MALLOC(n * sizeof(struct arc *));
+ if (sortarray == NULL)
+ {
+ NERR(REG_ESPACE);
+ return;
+ }
+ i = 0;
+ for (a = s->ins; a != NULL; a = a->inchain)
+ sortarray[i++] = a;
+ assert(i == n);
+ /* ... sort the array */
+ qsort(sortarray, n, sizeof(struct arc *), sortins_cmp);
+ /* ... and rebuild arc list in order */
+ /* it seems worth special-casing first and last items to simplify loop */
+ a = sortarray[0];
+ s->ins = a;
+ a->inchain = sortarray[1];
+ a->inchainRev = NULL;
+ for (i = 1; i < n - 1; i++)
+ {
+ a = sortarray[i];
+ a->inchain = sortarray[i + 1];
+ a->inchainRev = sortarray[i - 1];
+ }
+ a = sortarray[i];
+ a->inchain = NULL;
+ a->inchainRev = sortarray[i - 1];
+ FREE(sortarray);
+}
+
+static int
+sortins_cmp(const void *a, const void *b)
+{
+ const struct arc *aa = *((const struct arc * const *) a);
+ const struct arc *bb = *((const struct arc * const *) b);
+
+ /* we check the fields in the order they are most likely to be different */
+ if (aa->from->no < bb->from->no)
+ return -1;
+ if (aa->from->no > bb->from->no)
+ return 1;
+ if (aa->co < bb->co)
+ return -1;
+ if (aa->co > bb->co)
+ return 1;
+ if (aa->type < bb->type)
+ return -1;
+ if (aa->type > bb->type)
+ return 1;
+ return 0;
+}
+
+/*
+ * sortouts - sort the out arcs of a state by to/color/type
+ */
+static void
+sortouts(struct nfa * nfa,
+ struct state * s)
+{
+ struct arc **sortarray;
+ struct arc *a;
+ int n = s->nouts;
+ int i;
+
+ if (n <= 1)
+ return; /* nothing to do */
+ /* make an array of arc pointers ... */
+ sortarray = (struct arc **) MALLOC(n * sizeof(struct arc *));
+ if (sortarray == NULL)
+ {
+ NERR(REG_ESPACE);
+ return;
+ }
+ i = 0;
+ for (a = s->outs; a != NULL; a = a->outchain)
+ sortarray[i++] = a;
+ assert(i == n);
+ /* ... sort the array */
+ qsort(sortarray, n, sizeof(struct arc *), sortouts_cmp);
+ /* ... and rebuild arc list in order */
+ /* it seems worth special-casing first and last items to simplify loop */
+ a = sortarray[0];
+ s->outs = a;
+ a->outchain = sortarray[1];
+ a->outchainRev = NULL;
+ for (i = 1; i < n - 1; i++)
+ {
+ a = sortarray[i];
+ a->outchain = sortarray[i + 1];
+ a->outchainRev = sortarray[i - 1];
+ }
+ a = sortarray[i];
+ a->outchain = NULL;
+ a->outchainRev = sortarray[i - 1];
+ FREE(sortarray);
+}
+
+static int
+sortouts_cmp(const void *a, const void *b)
+{
+ const struct arc *aa = *((const struct arc * const *) a);
+ const struct arc *bb = *((const struct arc * const *) b);
+
+ /* we check the fields in the order they are most likely to be different */
+ if (aa->to->no < bb->to->no)
+ return -1;
+ if (aa->to->no > bb->to->no)
+ return 1;
+ if (aa->co < bb->co)
+ return -1;
+ if (aa->co > bb->co)
+ return 1;
+ if (aa->type < bb->type)
+ return -1;
+ if (aa->type > bb->type)
+ return 1;
+ return 0;
+}
+
+/*
+ * Common decision logic about whether to use arc-by-arc operations or
+ * sort/merge. If there's just a few source arcs we cannot recoup the
+ * cost of sorting the destination arc list, no matter how large it is.
+ * Otherwise, limit the number of arc-by-arc comparisons to about 1000
+ * (a somewhat arbitrary choice, but the breakeven point would probably
+ * be machine dependent anyway).
+ */
+#define BULK_ARC_OP_USE_SORT(nsrcarcs, ndestarcs) \
+ ((nsrcarcs) < 4 ? 0 : ((nsrcarcs) > 32 || (ndestarcs) > 32))
+
/*
* moveins - move all in arcs of a state to another state
*
* You might think this could be done better by just updating the
- * existing arcs, and you would be right if it weren't for the desire
+ * existing arcs, and you would be right if it weren't for the need
* for duplicate suppression, which makes it easier to just make new
* ones to exploit the suppression built into newarc.
+ *
+ * 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.
*/
static void
moveins(struct nfa * nfa,
struct state * oldState,
struct state * newState)
{
- struct arc *a;
-
assert(oldState != newState);
- while ((a = oldState->ins) != NULL)
+ if (!BULK_ARC_OP_USE_SORT(oldState->nins, newState->nins))
{
- cparc(nfa, a, a->from, newState);
- freearc(nfa, a);
+ /* With not too many arcs, just do them one at a time */
+ struct arc *a;
+
+ while ((a = oldState->ins) != NULL)
+ {
+ cparc(nfa, a, a->from, newState);
+ freearc(nfa, a);
+ }
+ }
+ else
+ {
+ /*
+ * With many arcs, use a sort-merge approach. Note changearctarget()
+ * will put the arc onto the front of newState's chain, so it does not
+ * break our walk through the sorted part of the chain.
+ */
+ struct arc *oa;
+ struct arc *na;
+
+ /*
+ * Because we bypass newarc() in this code path, we'd better include a
+ * cancel check.
+ */
+ if (CANCEL_REQUESTED(nfa->v->re))
+ {
+ NERR(REG_CANCEL);
+ return;
+ }
+
+ sortins(nfa, oldState);
+ sortins(nfa, newState);
+ if (NISERR())
+ return; /* might have failed to sort */
+ oa = oldState->ins;
+ na = newState->ins;
+ while (oa != NULL && na != NULL)
+ {
+ struct arc *a = oa;
+
+ switch (sortins_cmp(&oa, &na))
+ {
+ case -1:
+ /* newState does not have anything matching oa */
+ oa = oa->inchain;
+
+ /*
+ * Rather than doing createarc+freearc, we can just unlink
+ * and relink the existing arc struct.
+ */
+ changearctarget(a, newState);
+ break;
+ case 0:
+ /* match, advance in both lists */
+ oa = oa->inchain;
+ na = na->inchain;
+ /* ... and drop duplicate arc from oldState */
+ freearc(nfa, a);
+ break;
+ case +1:
+ /* advance only na; oa might have a match later */
+ na = na->inchain;
+ break;
+ default:
+ assert(NOTREACHED);
+ }
+ }
+ while (oa != NULL)
+ {
+ /* newState does not have anything matching oa */
+ struct arc *a = oa;
+
+ oa = oa->inchain;
+ changearctarget(a, newState);
+ }
}
+
assert(oldState->nins == 0);
assert(oldState->ins == NULL);
}
@@ -597,14 +913,187 @@ copyins(struct nfa * nfa,
struct state * newState,
int all)
{
- struct arc *a;
-
assert(oldState != newState);
- for (a = oldState->ins; a != NULL; a = a->inchain)
+ if (!BULK_ARC_OP_USE_SORT(oldState->nins, newState->nins))
{
- if (all || a->type != EMPTY)
- cparc(nfa, a, a->from, newState);
+ /* With not too many arcs, just do them one at a time */
+ struct arc *a;
+
+ for (a = oldState->ins; a != NULL; a = a->inchain)
+ if (all || a->type != EMPTY)
+ cparc(nfa, a, a->from, newState);
+ }
+ else
+ {
+ /*
+ * With many arcs, use a sort-merge approach. Note that createarc()
+ * will put new arcs onto the front of newState's chain, so it does
+ * not break our walk through the sorted part of the chain.
+ */
+ struct arc *oa;
+ struct arc *na;
+
+ /*
+ * Because we bypass newarc() in this code path, we'd better include a
+ * cancel check.
+ */
+ if (CANCEL_REQUESTED(nfa->v->re))
+ {
+ NERR(REG_CANCEL);
+ return;
+ }
+
+ sortins(nfa, oldState);
+ sortins(nfa, newState);
+ if (NISERR())
+ return; /* might have failed to sort */
+ oa = oldState->ins;
+ na = newState->ins;
+ while (oa != NULL && na != NULL)
+ {
+ struct arc *a = oa;
+
+ if (!all && a->type == EMPTY)
+ {
+ oa = oa->inchain;
+ continue;
+ }
+
+ switch (sortins_cmp(&oa, &na))
+ {
+ case -1:
+ /* newState does not have anything matching oa */
+ oa = oa->inchain;
+ createarc(nfa, a->type, a->co, a->from, newState);
+ break;
+ case 0:
+ /* match, advance in both lists */
+ oa = oa->inchain;
+ na = na->inchain;
+ break;
+ case +1:
+ /* advance only na; oa might have a match later */
+ na = na->inchain;
+ break;
+ default:
+ assert(NOTREACHED);
+ }
+ }
+ while (oa != NULL)
+ {
+ /* newState does not have anything matching oa */
+ struct arc *a = oa;
+
+ if (!all && a->type == EMPTY)
+ {
+ oa = oa->inchain;
+ continue;
+ }
+
+ oa = oa->inchain;
+ createarc(nfa, a->type, a->co, a->from, newState);
+ }
+ }
+}
+
+/*
+ * mergeins - merge a list of inarcs into a state
+ *
+ * This is much like copyins, but the source arcs are listed in an array,
+ * and are not guaranteed unique. It's okay to clobber the array contents.
+ */
+static void
+mergeins(struct nfa * nfa,
+ struct state * s,
+ struct arc ** arcarray,
+ int arccount)
+{
+ struct arc *na;
+ int i;
+ int j;
+
+ if (arccount <= 0)
+ return;
+
+ /*
+ * Because we bypass newarc() in this code path, we'd better include a
+ * cancel check.
+ */
+ if (CANCEL_REQUESTED(nfa->v->re))
+ {
+ NERR(REG_CANCEL);
+ return;
+ }
+
+ /* Sort existing inarcs as well as proposed new ones */
+ sortins(nfa, s);
+ if (NISERR())
+ return; /* might have failed to sort */
+
+ qsort(arcarray, arccount, sizeof(struct arc *), sortins_cmp);
+
+ /*
+ * arcarray very likely includes dups, so we must eliminate them. (This
+ * could be folded into the next loop, but it's not worth the trouble.)
+ */
+ j = 0;
+ for (i = 1; i < arccount; i++)
+ {
+ switch (sortins_cmp(&arcarray[j], &arcarray[i]))
+ {
+ case -1:
+ /* non-dup */
+ arcarray[++j] = arcarray[i];
+ break;
+ case 0:
+ /* dup */
+ break;
+ default:
+ /* trouble */
+ assert(NOTREACHED);
+ }
+ }
+ arccount = j + 1;
+
+ /*
+ * Now merge into s' inchain. Note that createarc() will put new arcs
+ * onto the front of s's chain, so it does not break our walk through the
+ * sorted part of the chain.
+ */
+ i = 0;
+ na = s->ins;
+ while (i < arccount && na != NULL)
+ {
+ struct arc *a = arcarray[i];
+
+ switch (sortins_cmp(&a, &na))
+ {
+ case -1:
+ /* s does not have anything matching a */
+ createarc(nfa, a->type, a->co, a->from, s);
+ i++;
+ break;
+ case 0:
+ /* match, advance in both lists */
+ i++;
+ na = na->inchain;
+ break;
+ case +1:
+ /* advance only na; array might have a match later */
+ na = na->inchain;
+ break;
+ default:
+ assert(NOTREACHED);
+ }
+ }
+ while (i < arccount)
+ {
+ /* s does not have anything matching a */
+ struct arc *a = arcarray[i];
+
+ createarc(nfa, a->type, a->co, a->from, s);
+ i++;
}
}
@@ -616,15 +1105,85 @@ moveouts(struct nfa * nfa,
struct state * oldState,
struct state * newState)
{
- struct arc *a;
-
assert(oldState != newState);
- while ((a = oldState->outs) != NULL)
+ if (!BULK_ARC_OP_USE_SORT(oldState->nouts, newState->nouts))
{
- cparc(nfa, a, newState, a->to);
- freearc(nfa, a);
+ /* With not too many arcs, just do them one at a time */
+ struct arc *a;
+
+ while ((a = oldState->outs) != NULL)
+ {
+ cparc(nfa, a, newState, a->to);
+ freearc(nfa, a);
+ }
+ }
+ else
+ {
+ /*
+ * With many arcs, use a sort-merge approach. Note that createarc()
+ * will put new arcs onto the front of newState's chain, so it does
+ * not break our walk through the sorted part of the chain.
+ */
+ struct arc *oa;
+ struct arc *na;
+
+ /*
+ * Because we bypass newarc() in this code path, we'd better include a
+ * cancel check.
+ */
+ if (CANCEL_REQUESTED(nfa->v->re))
+ {
+ NERR(REG_CANCEL);
+ return;
+ }
+
+ sortouts(nfa, oldState);
+ sortouts(nfa, newState);
+ if (NISERR())
+ return; /* might have failed to sort */
+ oa = oldState->outs;
+ na = newState->outs;
+ while (oa != NULL && na != NULL)
+ {
+ struct arc *a = oa;
+
+ switch (sortouts_cmp(&oa, &na))
+ {
+ case -1:
+ /* newState does not have anything matching oa */
+ oa = oa->outchain;
+ createarc(nfa, a->type, a->co, newState, a->to);
+ freearc(nfa, a);
+ break;
+ case 0:
+ /* match, advance in both lists */
+ oa = oa->outchain;
+ na = na->outchain;
+ /* ... and drop duplicate arc from oldState */
+ freearc(nfa, a);
+ break;
+ case +1:
+ /* advance only na; oa might have a match later */
+ na = na->outchain;
+ break;
+ default:
+ assert(NOTREACHED);
+ }
+ }
+ while (oa != NULL)
+ {
+ /* newState does not have anything matching oa */
+ struct arc *a = oa;
+
+ oa = oa->outchain;
+ createarc(nfa, a->type, a->co, newState, a->to);
+ freearc(nfa, a);
+ }
}
+
+ assert(oldState->nouts == 0);
+ assert(oldState->outs == NULL);
}
/*
@@ -638,14 +1197,87 @@ copyouts(struct nfa * nfa,
struct state * newState,
int all)
{
- struct arc *a;
-
assert(oldState != newState);
- for (a = oldState->outs; a != NULL; a = a->outchain)
+ if (!BULK_ARC_OP_USE_SORT(oldState->nouts, newState->nouts))
{
- if (all || a->type != EMPTY)
- cparc(nfa, a, newState, a->to);
+ /* With not too many arcs, just do them one at a time */
+ struct arc *a;
+
+ for (a = oldState->outs; a != NULL; a = a->outchain)
+ if (all || a->type != EMPTY)
+ cparc(nfa, a, newState, a->to);
+ }
+ else
+ {
+ /*
+ * With many arcs, use a sort-merge approach. Note that createarc()
+ * will put new arcs onto the front of newState's chain, so it does
+ * not break our walk through the sorted part of the chain.
+ */
+ struct arc *oa;
+ struct arc *na;
+
+ /*
+ * Because we bypass newarc() in this code path, we'd better include a
+ * cancel check.
+ */
+ if (CANCEL_REQUESTED(nfa->v->re))
+ {
+ NERR(REG_CANCEL);
+ return;
+ }
+
+ sortouts(nfa, oldState);
+ sortouts(nfa, newState);
+ if (NISERR())
+ return; /* might have failed to sort */
+ oa = oldState->outs;
+ na = newState->outs;
+ while (oa != NULL && na != NULL)
+ {
+ struct arc *a = oa;
+
+ if (!all && a->type == EMPTY)
+ {
+ oa = oa->outchain;
+ continue;
+ }
+
+ switch (sortouts_cmp(&oa, &na))
+ {
+ case -1:
+ /* newState does not have anything matching oa */
+ oa = oa->outchain;
+ createarc(nfa, a->type, a->co, newState, a->to);
+ break;
+ case 0:
+ /* match, advance in both lists */
+ oa = oa->outchain;
+ na = na->outchain;
+ break;
+ case +1:
+ /* advance only na; oa might have a match later */
+ na = na->outchain;
+ break;
+ default:
+ assert(NOTREACHED);
+ }
+ }
+ while (oa != NULL)
+ {
+ /* newState does not have anything matching oa */
+ struct arc *a = oa;
+
+ if (!all && a->type == EMPTY)
+ {
+ oa = oa->outchain;
+ continue;
+ }
+
+ oa = oa->outchain;
+ createarc(nfa, a->type, a->co, newState, a->to);
+ }
}
}
@@ -2217,7 +2849,7 @@ compact(struct nfa * nfa,
NERR(REG_ASSERT);
break;
}
- carcsort(first, ca - 1);
+ carcsort(first, ca - first);
ca->co = COLORLESS;
ca->to = 0;
ca++;
@@ -2233,31 +2865,29 @@ compact(struct nfa * nfa,
/*
* carcsort - sort compacted-NFA arcs by color
- *
- * Really dumb algorithm, but if the list is long enough for that to matter,
- * you're in real trouble anyway.
*/
static void
-carcsort(struct carc * first,
- struct carc * last)
+carcsort(struct carc * first, size_t n)
{
- struct carc *p;
- struct carc *q;
- struct carc tmp;
-
- if (last - first <= 1)
- return;
+ if (n > 1)
+ qsort(first, n, sizeof(struct carc), carc_cmp);
+}
- for (p = first; p <= last; p++)
- for (q = p; q <= last; q++)
- if (p->co > q->co ||
- (p->co == q->co && p->to > q->to))
- {
- assert(p != q);
- tmp = *p;
- *p = *q;
- *q = tmp;
- }
+static int
+carc_cmp(const void *a, const void *b)
+{
+ const struct carc *aa = (const struct carc *) a;
+ const struct carc *bb = (const struct carc *) b;
+
+ if (aa->co < bb->co)
+ return -1;
+ if (aa->co > bb->co)
+ return +1;
+ if (aa->to < bb->to)
+ return -1;
+ if (aa->to > bb->to)
+ return +1;
+ return 0;
}
/*
@@ -2337,34 +2967,28 @@ dumparcs(struct state * s,
FILE *f)
{
int pos;
+ struct arc *a;
- assert(s->nouts > 0);
- /* printing arcs in reverse order is usually clearer */
- pos = dumprarcs(s->outs, s, f, 1);
- if (pos != 1)
- fprintf(f, "\n");
-}
-
-/*
- * dumprarcs - dump remaining outarcs, recursively, in reverse order
- */
-static int /* resulting print position */
-dumprarcs(struct arc * a,
- struct state * s,
- FILE *f,
- int pos) /* initial print position */
-{
- if (a->outchain != NULL)
- pos = dumprarcs(a->outchain, s, f, pos);
- dumparc(a, s, f);
- if (pos == 5)
+ /* printing oldest arcs first is usually clearer */
+ a = s->outs;
+ assert(a != NULL);
+ while (a->outchain != NULL)
+ a = a->outchain;
+ pos = 1;
+ do
{
+ dumparc(a, s, f);
+ if (pos == 5)
+ {
+ fprintf(f, "\n");
+ pos = 1;
+ }
+ else
+ pos++;
+ a = a->outchainRev;
+ } while (a != NULL);
+ if (pos != 1)
fprintf(f, "\n");
- pos = 1;
- }
- else
- pos++;
- return pos;
}
/*
diff --git a/src/backend/regex/regcomp.c b/src/backend/regex/regcomp.c
index bc38192d07b93242414b03f627dc4c6909d030b4..ad9a79702cabecbfaa1fbe2edbe316b94913823b 100644
--- a/src/backend/regex/regcomp.c
+++ b/src/backend/regex/regcomp.c
@@ -124,15 +124,22 @@ static void dropstate(struct nfa *, struct state *);
static void freestate(struct nfa *, struct state *);
static void destroystate(struct nfa *, struct state *);
static void newarc(struct nfa *, int, pcolor, struct state *, struct state *);
+static void createarc(struct nfa *, int, pcolor, struct state *, struct state *);
static struct arc *allocarc(struct nfa *, struct state *);
static void freearc(struct nfa *, struct arc *);
+static void changearctarget(struct arc *, struct state *);
static int hasnonemptyout(struct state *);
static int nonemptyouts(struct state *);
static int nonemptyins(struct state *);
static struct arc *findarc(struct state *, int, pcolor);
static void cparc(struct nfa *, struct arc *, struct state *, struct state *);
+static void sortins(struct nfa *, struct state *);
+static int sortins_cmp(const void *, const void *);
+static void sortouts(struct nfa *, struct state *);
+static int sortouts_cmp(const void *, const void *);
static void moveins(struct nfa *, struct state *, struct state *);
static void copyins(struct nfa *, struct state *, struct state *, int);
+static void mergeins(struct nfa *, struct state *, struct arc **, int);
static void moveouts(struct nfa *, struct state *, struct state *);
static void copyouts(struct nfa *, struct state *, struct state *, int);
static void cloneouts(struct nfa *, struct state *, struct state *, struct state *, int);
@@ -168,7 +175,8 @@ static void markreachable(struct nfa *, struct state *, struct state *, struct s
static void markcanreach(struct nfa *, struct state *, struct state *, struct state *);
static long analyze(struct nfa *);
static void compact(struct nfa *, struct cnfa *);
-static void carcsort(struct carc *, struct carc *);
+static void carcsort(struct carc *, size_t);
+static int carc_cmp(const void *, const void *);
static void freecnfa(struct cnfa *);
static void dumpnfa(struct nfa *, FILE *);
diff --git a/src/include/regex/regguts.h b/src/include/regex/regguts.h
index 327775235514e96de2352a1665e81db2a95a5a4a..357891aa254847f9eba290b9e4f749ff59cd2bd9 100644
--- a/src/include/regex/regguts.h
+++ b/src/include/regex/regguts.h
@@ -289,8 +289,10 @@ struct arc
struct state *from; /* where it's from (and contained within) */
struct state *to; /* where it's to */
struct arc *outchain; /* link in *from's outs chain or free chain */
-#define freechain outchain
+ struct arc *outchainRev; /* back-link in *from's outs chain */
+#define freechain outchain /* we do not maintain "freechainRev" */
struct arc *inchain; /* link in *to's ins chain */
+ struct arc *inchainRev; /* back-link in *to's ins chain */
struct arc *colorchain; /* link in color's arc chain */
struct arc *colorchainRev; /* back-link in color's arc chain */
};