* win/Makefile.in: Added tcltest target so runtest works

properly.  Added missing names to the clean/distclean targets.

* tests/reg.test:
* generic/rege_dfa.c: Applied fix supplied by Henry Spencer for
bug in DFA state caching under lookahead conditions.  [Bug: 2318]

1 files changed, 677 insertions, 674 deletions

diff --git a/generic/rege_dfa.c b/generic/rege_dfa.c
index a13dfa4..24ff2db 100644
--- a/generic/rege_dfa.c
+++ b/generic/rege_dfa.c
@@ -1,674 +1,677 @@
-/*
- * DFA routines
- * This file is #included by regexec.c.
- *
- * Copyright (c) 1998, 1999 Henry Spencer.  All rights reserved.
- * 
- * Development of this software was funded, in part, by Cray Research Inc.,
- * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics
- * Corporation, none of whom are responsible for the results.  The author
- * thanks all of them. 
- * 
- * Redistribution and use in source and binary forms -- with or without
- * modification -- are permitted for any purpose, provided that
- * redistributions in source form retain this entire copyright notice and
- * indicate the origin and nature of any modifications.
- * 
- * I'd appreciate being given credit for this package in the documentation
- * of software which uses it, but that is not a requirement.
- * 
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
- * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
- * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
- * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
- * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
- * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
- * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
- * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
- * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
- * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- *
- */
-
-/*
- - longest - longest-preferred matching engine
- ^ static chr *longest(struct vars *, struct dfa *, chr *, chr *, int *);
- */
-static chr *			/* endpoint, or NULL */
-longest(v, d, start, stop, hitstopp)
-struct vars *v;			/* used only for debug and exec flags */
-struct dfa *d;
-chr *start;			/* where the match should start */
-chr *stop;			/* match must end at or before here */
-int *hitstopp;			/* record whether hit v->stop, if non-NULL */
-{
-	chr *cp;
-	chr *realstop = (stop == v->stop) ? stop : stop + 1;
-	color co;
-	struct sset *css;
-	struct sset *ss;
-	chr *post;
-	int i;
-	struct colormap *cm = d->cm;
-
-	/* initialize */
-	css = initialize(v, d, start);
-	cp = start;
-	if (hitstopp != NULL)
-		*hitstopp = 0;
-
-	/* startup */
-	FDEBUG(("+++ startup +++\n"));
-	if (cp == v->start) {
-		co = d->cnfa->bos[(v->eflags&REG_NOTBOL) ? 0 : 1];
-		FDEBUG(("color %ld\n", (long)co));
-	} else {
-		co = GETCOLOR(cm, *(cp - 1));
-		FDEBUG(("char %c, color %ld\n", (char)*(cp-1), (long)co));
-	}
-	css = miss(v, d, css, co, cp, start);
-	if (css == NULL)
-		return NULL;
-	css->lastseen = cp;
-
-	/* main loop */
-	if (v->eflags&REG_FTRACE)
-		while (cp < realstop) {
-			FDEBUG(("+++ at c%d +++\n", css - d->ssets));
-			co = GETCOLOR(cm, *cp);
-			FDEBUG(("char %c, color %ld\n", (char)*cp, (long)co));
-			ss = css->outs[co];
-			if (ss == NULL) {
-				ss = miss(v, d, css, co, cp+1, start);
-				if (ss == NULL)
-					break;	/* NOTE BREAK OUT */
-			}
-			cp++;
-			ss->lastseen = cp;
-			css = ss;
-		}
-	else
-		while (cp < realstop) {
-			co = GETCOLOR(cm, *cp);
-			ss = css->outs[co];
-			if (ss == NULL) {
-				ss = miss(v, d, css, co, cp+1, start);
-				if (ss == NULL)
-					break;	/* NOTE BREAK OUT */
-			}
-			cp++;
-			ss->lastseen = cp;
-			css = ss;
-		}
-
-	/* shutdown */
-	FDEBUG(("+++ shutdown at c%d +++\n", css - d->ssets));
-	if (cp == v->stop && stop == v->stop) {
-		if (hitstopp != NULL)
-			*hitstopp = 1;
-		co = d->cnfa->eos[(v->eflags&REG_NOTEOL) ? 0 : 1];
-		FDEBUG(("color %ld\n", (long)co));
-		ss = miss(v, d, css, co, cp, start);
-		/* special case:  match ended at eol? */
-		if (ss != NULL && (ss->flags&POSTSTATE))
-			return cp;
-		else if (ss != NULL)
-			ss->lastseen = cp;	/* to be tidy */
-	}
-
-	/* find last match, if any */
-	post = d->lastpost;
-	for (ss = d->ssets, i = d->nssused; i > 0; ss++, i--)
-		if ((ss->flags&POSTSTATE) && post != ss->lastseen &&
-					(post == NULL || post < ss->lastseen))
-			post = ss->lastseen;
-	if (post != NULL)		/* found one */
-		return post - 1;
-
-	return NULL;
-}
-
-/*
- - shortest - shortest-preferred matching engine
- ^ static chr *shortest(struct vars *, struct dfa *, chr *, chr *, chr *,
- ^ 	chr **, int *);
- */
-static chr *			/* endpoint, or NULL */
-shortest(v, d, start, min, max, coldp, hitstopp)
-struct vars *v;
-struct dfa *d;
-chr *start;			/* where the match should start */
-chr *min;			/* match must end at or after here */
-chr *max;			/* match must end at or before here */
-chr **coldp;			/* store coldstart pointer here, if nonNULL */
-int *hitstopp;			/* record whether hit v->stop, if non-NULL */
-{
-	chr *cp;
-	chr *realmin = (min == v->stop) ? min : min + 1;
-	chr *realmax = (max == v->stop) ? max : max + 1;
-	color co;
-	struct sset *css;
-	struct sset *ss;
-	struct colormap *cm = d->cm;
-
-	/* initialize */
-	css = initialize(v, d, start);
-	cp = start;
-	if (hitstopp != NULL)
-		*hitstopp = 0;
-
-	/* startup */
-	FDEBUG(("--- startup ---\n"));
-	if (cp == v->start) {
-		co = d->cnfa->bos[(v->eflags&REG_NOTBOL) ? 0 : 1];
-		FDEBUG(("color %ld\n", (long)co));
-	} else {
-		co = GETCOLOR(cm, *(cp - 1));
-		FDEBUG(("char %c, color %ld\n", (char)*(cp-1), (long)co));
-	}
-	css = miss(v, d, css, co, cp, start);
-	if (css == NULL)
-		return NULL;
-	css->lastseen = cp;
-	ss = css;
-
-	/* main loop */
-	if (v->eflags&REG_FTRACE)
-		while (cp < realmax) {
-			FDEBUG(("--- at c%d ---\n", css - d->ssets));
-			co = GETCOLOR(cm, *cp);
-			FDEBUG(("char %c, color %ld\n", (char)*cp, (long)co));
-			ss = css->outs[co];
-			if (ss == NULL) {
-				ss = miss(v, d, css, co, cp+1, start);
-				if (ss == NULL)
-					break;	/* NOTE BREAK OUT */
-			}
-			cp++;
-			ss->lastseen = cp;
-			css = ss;
-			if ((ss->flags&POSTSTATE) && cp >= realmin)
-				break;		/* NOTE BREAK OUT */
-		}
-	else
-		while (cp < realmax) {
-			co = GETCOLOR(cm, *cp);
-			ss = css->outs[co];
-			if (ss == NULL) {
-				ss = miss(v, d, css, co, cp+1, start);
-				if (ss == NULL)
-					break;	/* NOTE BREAK OUT */
-			}
-			cp++;
-			ss->lastseen = cp;
-			css = ss;
-			if ((ss->flags&POSTSTATE) && cp >= realmin)
-				break;		/* NOTE BREAK OUT */
-		}
-
-	if (ss == NULL)
-		return NULL;
-
-	if (coldp != NULL)	/* report last no-progress state set, if any */
-		*coldp = lastcold(v, d);
-
-	if ((ss->flags&POSTSTATE) && cp > min) {
-		assert(cp >= realmin);
-		cp--;
-	} else if (cp == v->stop && max == v->stop) {
-		co = d->cnfa->eos[(v->eflags&REG_NOTEOL) ? 0 : 1];
-		FDEBUG(("color %ld\n", (long)co));
-		ss = miss(v, d, css, co, cp, start);
-		/* match might have ended at eol */
-		if ((ss == NULL || !(ss->flags&POSTSTATE)) && hitstopp != NULL)
-			*hitstopp = 1;
-	}
-
-	if (ss == NULL || !(ss->flags&POSTSTATE))
-		return NULL;
-
-	return cp;
-}
-
-/*
- - lastcold - determine last point at which no progress had been made
- ^ static chr *lastcold(struct vars *, struct dfa *);
- */
-static chr *			/* endpoint, or NULL */
-lastcold(v, d)
-struct vars *v;
-struct dfa *d;
-{
-	struct sset *ss;
-	chr *nopr;
-	int i;
-
-	nopr = d->lastnopr;
-	if (nopr == NULL)
-		nopr = v->start;
-	for (ss = d->ssets, i = d->nssused; i > 0; ss++, i--)
-		if ((ss->flags&NOPROGRESS) && nopr < ss->lastseen)
-			nopr = ss->lastseen;
-	return nopr;
-}
-
-/*
- - newdfa - set up a fresh DFA
- ^ static struct dfa *newdfa(struct vars *, struct cnfa *,
- ^ 	struct colormap *, struct smalldfa *);
- */
-static struct dfa *
-newdfa(v, cnfa, cm, small)
-struct vars *v;
-struct cnfa *cnfa;
-struct colormap *cm;
-struct smalldfa *small;		/* preallocated space, may be NULL */
-{
-	struct dfa *d;
-	size_t nss = cnfa->nstates * 2;
-	int wordsper = (cnfa->nstates + UBITS - 1) / UBITS;
-	struct smalldfa *smallwas = small;
-
-	assert(cnfa != NULL && cnfa->nstates != 0);
-
-	if (nss <= FEWSTATES && cnfa->ncolors <= FEWCOLORS) {
-		assert(wordsper == 1);
-		if (small == NULL) {
-			small = (struct smalldfa *)MALLOC(
-						sizeof(struct smalldfa));
-			if (small == NULL) {
-				ERR(REG_ESPACE);
-				return NULL;
-			}
-		}
-		d = &small->dfa;
-		d->ssets = small->ssets;
-		d->statesarea = small->statesarea;
-		d->work = &d->statesarea[nss];
-		d->outsarea = small->outsarea;
-		d->incarea = small->incarea;
-		d->cptsmalloced = 0;
-		d->mallocarea = (smallwas == NULL) ? (char *)small : NULL;
-	} else {
-		d = (struct dfa *)MALLOC(sizeof(struct dfa));
-		if (d == NULL) {
-			ERR(REG_ESPACE);
-			return NULL;
-		}
-		d->ssets = (struct sset *)MALLOC(nss * sizeof(struct sset));
-		d->statesarea = (unsigned *)MALLOC((nss+WORK) * wordsper *
-							sizeof(unsigned));
-		d->work = &d->statesarea[nss * wordsper];
-		d->outsarea = (struct sset **)MALLOC(nss * cnfa->ncolors *
-							sizeof(struct sset *));
-		d->incarea = (struct arcp *)MALLOC(nss * cnfa->ncolors *
-							sizeof(struct arcp));
-		d->cptsmalloced = 1;
-		d->mallocarea = (char *)d;
-		if (d->ssets == NULL || d->statesarea == NULL ||
-				d->outsarea == NULL || d->incarea == NULL) {
-			freedfa(d);
-			ERR(REG_ESPACE);
-			return NULL;
-		}
-	}
-
-	d->nssets = (v->eflags&REG_SMALL) ? 7 : nss;
-	d->nssused = 0;
-	d->nstates = cnfa->nstates;
-	d->ncolors = cnfa->ncolors;
-	d->wordsper = wordsper;
-	d->cnfa = cnfa;
-	d->cm = cm;
-	d->lastpost = NULL;
-	d->lastnopr = NULL;
-	d->search = d->ssets;
-
-	/* initialization of sset fields is done as needed */
-
-	return d;
-}
-
-/*
- - freedfa - free a DFA
- ^ static VOID freedfa(struct dfa *);
- */
-static VOID
-freedfa(d)
-struct dfa *d;
-{
-	if (d->cptsmalloced) {
-		if (d->ssets != NULL)
-			FREE(d->ssets);
-		if (d->statesarea != NULL)
-			FREE(d->statesarea);
-		if (d->outsarea != NULL)
-			FREE(d->outsarea);
-		if (d->incarea != NULL)
-			FREE(d->incarea);
-	}
-
-	if (d->mallocarea != NULL)
-		FREE(d->mallocarea);
-}
-
-/*
- - hash - construct a hash code for a bitvector
- * There are probably better ways, but they're more expensive.
- ^ static unsigned hash(unsigned *, int);
- */
-static unsigned
-hash(uv, n)
-unsigned *uv;
-int n;
-{
-	int i;
-	unsigned h;
-
-	h = 0;
-	for (i = 0; i < n; i++)
-		h ^= uv[i];
-	return h;
-}
-
-/*
- - initialize - hand-craft a cache entry for startup, otherwise get ready
- ^ static struct sset *initialize(struct vars *, struct dfa *, chr *);
- */
-static struct sset *
-initialize(v, d, start)
-struct vars *v;			/* used only for debug flags */
-struct dfa *d;
-chr *start;
-{
-	struct sset *ss;
-	int i;
-
-	/* is previous one still there? */
-	if (d->nssused > 0 && (d->ssets[0].flags&STARTER))
-		ss = &d->ssets[0];
-	else {				/* no, must (re)build it */
-		ss = getvacant(v, d, start, start);
-		for (i = 0; i < d->wordsper; i++)
-			ss->states[i] = 0;
-		BSET(ss->states, d->cnfa->pre);
-		ss->hash = HASH(ss->states, d->wordsper);
-		assert(d->cnfa->pre != d->cnfa->post);
-		ss->flags = STARTER|LOCKED|NOPROGRESS;
-		/* lastseen dealt with below */
-	}
-
-	for (i = 0; i < d->nssused; i++)
-		d->ssets[i].lastseen = NULL;
-	ss->lastseen = start;		/* maybe untrue, but harmless */
-	d->lastpost = NULL;
-	d->lastnopr = NULL;
-	return ss;
-}
-
-/*
- - miss - handle a cache miss
- ^ static struct sset *miss(struct vars *, struct dfa *, struct sset *,
- ^ 	pcolor, chr *, chr *);
- */
-static struct sset *		/* NULL if goes to empty set */
-miss(v, d, css, co, cp, start)
-struct vars *v;			/* used only for debug flags */
-struct dfa *d;
-struct sset *css;
-pcolor co;
-chr *cp;			/* next chr */
-chr *start;			/* where the attempt got started */
-{
-	struct cnfa *cnfa = d->cnfa;
-	int i;
-	unsigned h;
-	struct carc *ca;
-	struct sset *p;
-	int ispost;
-	int noprogress;
-	int gotstate;
-	int dolacons;
-	int didlacons;
-
-	/* for convenience, we can be called even if it might not be a miss */
-	if (css->outs[co] != NULL) {
-		FDEBUG(("hit\n"));
-		return css->outs[co];
-	}
-	FDEBUG(("miss\n"));
-
-	/* first, what set of states would we end up in? */
-	for (i = 0; i < d->wordsper; i++)
-		d->work[i] = 0;
-	ispost = 0;
-	noprogress = 1;
-	gotstate = 0;
-	for (i = 0; i < d->nstates; i++)
-		if (ISBSET(css->states, i))
-			for (ca = cnfa->states[i]+1; ca->co != COLORLESS; ca++)
-				if (ca->co == co) {
-					BSET(d->work, ca->to);
-					gotstate = 1;
-					if (ca->to == cnfa->post)
-						ispost = 1;
-					if (!cnfa->states[ca->to]->co)
-						noprogress = 0;
-					FDEBUG(("%d -> %d\n", i, ca->to));
-				}
-	dolacons = (gotstate) ? (cnfa->flags&HASLACONS) : 0;
-	didlacons = 0;
-	while (dolacons) {		/* transitive closure */
-		dolacons = 0;
-		for (i = 0; i < d->nstates; i++)
-			if (ISBSET(d->work, i))
-				for (ca = cnfa->states[i]+1; ca->co != COLORLESS;
-									ca++)
-					if (ca->co > cnfa->ncolors &&
-						!ISBSET(d->work, ca->to) &&
-							lacon(v, cnfa, cp,
-								ca->co)) {
-						BSET(d->work, ca->to);
-						dolacons = 1;
-						didlacons = 1;
-						if (ca->to == cnfa->post)
-							ispost = 1;
-						if (!cnfa->states[ca->to]->co)
-							noprogress = 0;
-						FDEBUG(("%d :> %d\n",i,ca->to));
-					}
-	}
-	if (!gotstate)
-		return NULL;
-	h = HASH(d->work, d->wordsper);
-
-	/* next, is that in the cache? */
-	for (p = d->ssets, i = d->nssused; i > 0; p++, i--)
-		if (HIT(h, d->work, p, d->wordsper)) {
-			FDEBUG(("cached c%d\n", p - d->ssets));
-			break;			/* NOTE BREAK OUT */
-		}
-	if (i == 0) {		/* nope, need a new cache entry */
-		p = getvacant(v, d, cp, start);
-		assert(p != css);
-		for (i = 0; i < d->wordsper; i++)
-			p->states[i] = d->work[i];
-		p->hash = h;
-		p->flags = (ispost) ? POSTSTATE : 0;
-		if (noprogress)
-			p->flags |= NOPROGRESS;
-		/* lastseen to be dealt with by caller */
-	}
-
-	if (!didlacons) {		/* lookahead conds. always cache miss */
-		css->outs[co] = p;
-		css->inchain[co] = p->ins;
-		p->ins.ss = css;
-		p->ins.co = (color)co;
-	}
-	return p;
-}
-
-/*
- - lacon - lookahead-constraint checker for miss()
- ^ static int lacon(struct vars *, struct cnfa *, chr *, pcolor);
- */
-static int			/* predicate:  constraint satisfied? */
-lacon(v, pcnfa, cp, co)
-struct vars *v;
-struct cnfa *pcnfa;		/* parent cnfa */
-chr *cp;
-pcolor co;			/* "color" of the lookahead constraint */
-{
-	int n;
-	struct subre *sub;
-	struct dfa *d;
-	struct smalldfa sd;
-	chr *end;
-
-	n = co - pcnfa->ncolors;
-	assert(n < v->g->nlacons && v->g->lacons != NULL);
-	FDEBUG(("=== testing lacon %d\n", n));
-	sub = &v->g->lacons[n];
-	d = newdfa(v, &sub->cnfa, &v->g->cmap, &sd);
-	if (d == NULL) {
-		ERR(REG_ESPACE);
-		return 0;
-	}
-	end = longest(v, d, cp, v->stop, (int *)NULL);
-	freedfa(d);
-	FDEBUG(("=== lacon %d match %d\n", n, (end != NULL)));
-	return (sub->subno) ? (end != NULL) : (end == NULL);
-}
-
-/*
- - getvacant - get a vacant state set
- * This routine clears out the inarcs and outarcs, but does not otherwise
- * clear the innards of the state set -- that's up to the caller.
- ^ static struct sset *getvacant(struct vars *, struct dfa *, chr *, chr *);
- */
-static struct sset *
-getvacant(v, d, cp, start)
-struct vars *v;			/* used only for debug flags */
-struct dfa *d;
-chr *cp;
-chr *start;
-{
-	int i;
-	struct sset *ss;
-	struct sset *p;
-	struct arcp ap;
-	struct arcp lastap;
-	color co;
-
-	ss = pickss(v, d, cp, start);
-	assert(!(ss->flags&LOCKED));
-
-	/* clear out its inarcs, including self-referential ones */
-	ap = ss->ins;
-	while ((p = ap.ss) != NULL) {
-		co = ap.co;
-		FDEBUG(("zapping c%d's %ld outarc\n", p - d->ssets, (long)co));
-		p->outs[co] = NULL;
-		ap = p->inchain[co];
-		p->inchain[co].ss = NULL;	/* paranoia */
-	}
-	ss->ins.ss = NULL;
-
-	/* take it off the inarc chains of the ssets reached by its outarcs */
-	for (i = 0; i < d->ncolors; i++) {
-		p = ss->outs[i];
-		assert(p != ss);		/* not self-referential */
-		if (p == NULL)
-			continue;		/* NOTE CONTINUE */
-		FDEBUG(("del outarc %d from c%d's in chn\n", i, p - d->ssets));
-		if (p->ins.ss == ss && p->ins.co == i)
-			p->ins = ss->inchain[i];
-		else {
-			assert(p->ins.ss != NULL);
-			for (ap = p->ins; ap.ss != NULL &&
-						!(ap.ss == ss && ap.co == i);
-						ap = ap.ss->inchain[ap.co])
-				lastap = ap;
-			assert(ap.ss != NULL);
-			lastap.ss->inchain[lastap.co] = ss->inchain[i];
-		}
-		ss->outs[i] = NULL;
-		ss->inchain[i].ss = NULL;
-	}
-
-	/* if ss was a success state, may need to remember location */
-	if ((ss->flags&POSTSTATE) && ss->lastseen != d->lastpost &&
-			(d->lastpost == NULL || d->lastpost < ss->lastseen))
-		d->lastpost = ss->lastseen;
-
-	/* likewise for a no-progress state */
-	if ((ss->flags&NOPROGRESS) && ss->lastseen != d->lastnopr &&
-			(d->lastnopr == NULL || d->lastnopr < ss->lastseen))
-		d->lastnopr = ss->lastseen;
-
-	return ss;
-}
-
-/*
- - pickss - pick the next stateset to be used
- ^ static struct sset *pickss(struct vars *, struct dfa *, chr *, chr *);
- */
-static struct sset *
-pickss(v, d, cp, start)
-struct vars *v;			/* used only for debug flags */
-struct dfa *d;
-chr *cp;
-chr *start;
-{
-	int i;
-	struct sset *ss;
-	struct sset *end;
-	chr *ancient;
-
-	/* shortcut for cases where cache isn't full */
-	if (d->nssused < d->nssets) {
-		i = d->nssused;
-		d->nssused++;
-		ss = &d->ssets[i];
-		FDEBUG(("new c%d\n", i));
-		/* set up innards */
-		ss->states = &d->statesarea[i * d->wordsper];
-		ss->flags = 0;
-		ss->ins.ss = NULL;
-		ss->ins.co = WHITE;		/* give it some value */
-		ss->outs = &d->outsarea[i * d->ncolors];
-		ss->inchain = &d->incarea[i * d->ncolors];
-		for (i = 0; i < d->ncolors; i++) {
-			ss->outs[i] = NULL;
-			ss->inchain[i].ss = NULL;
-		}
-		return ss;
-	}
-
-	/* look for oldest, or old enough anyway */
-	if (cp - start > d->nssets*2/3)		/* oldest 33% are expendable */
-		ancient = cp - d->nssets*2/3;
-	else
-		ancient = start;
-	for (ss = d->search, end = &d->ssets[d->nssets]; ss < end; ss++)
-		if ((ss->lastseen == NULL || ss->lastseen < ancient) &&
-							!(ss->flags&LOCKED)) {
-			d->search = ss + 1;
-			FDEBUG(("replacing c%d\n", ss - d->ssets));
-			return ss;
-		}
-	for (ss = d->ssets, end = d->search; ss < end; ss++)
-		if ((ss->lastseen == NULL || ss->lastseen < ancient) &&
-							!(ss->flags&LOCKED)) {
-			d->search = ss + 1;
-			FDEBUG(("replacing c%d\n", ss - d->ssets));
-			return ss;
-		}
-
-	/* nobody's old enough?!? -- something's really wrong */
-	FDEBUG(("can't find victim to replace!\n"));
-	assert(NOTREACHED);
-	ERR(REG_ASSERT);
-	return d->ssets;
-}
+/*

+ * DFA routines

+ * This file is #included by regexec.c.

+ *

+ * Copyright (c) 1998, 1999 Henry Spencer.  All rights reserved.

+ * 

+ * Development of this software was funded, in part, by Cray Research Inc.,

+ * UUNET Communications Services Inc., Sun Microsystems Inc., and Scriptics

+ * Corporation, none of whom are responsible for the results.  The author

+ * thanks all of them. 

+ * 

+ * Redistribution and use in source and binary forms -- with or without

+ * modification -- are permitted for any purpose, provided that

+ * redistributions in source form retain this entire copyright notice and

+ * indicate the origin and nature of any modifications.

+ * 

+ * I'd appreciate being given credit for this package in the documentation

+ * of software which uses it, but that is not a requirement.

+ * 

+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,

+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY

+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL

+ * HENRY SPENCER BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;

+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,

+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR

+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF

+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

+ *

+ */

+

+/*

+ - longest - longest-preferred matching engine

+ ^ static chr *longest(struct vars *, struct dfa *, chr *, chr *, int *);

+ */

+static chr *			/* endpoint, or NULL */

+longest(v, d, start, stop, hitstopp)

+struct vars *v;			/* used only for debug and exec flags */

+struct dfa *d;

+chr *start;			/* where the match should start */

+chr *stop;			/* match must end at or before here */

+int *hitstopp;			/* record whether hit v->stop, if non-NULL */

+{

+	chr *cp;

+	chr *realstop = (stop == v->stop) ? stop : stop + 1;

+	color co;

+	struct sset *css;

+	struct sset *ss;

+	chr *post;

+	int i;

+	struct colormap *cm = d->cm;

+

+	/* initialize */

+	css = initialize(v, d, start);

+	cp = start;

+	if (hitstopp != NULL)

+		*hitstopp = 0;

+

+	/* startup */

+	FDEBUG(("+++ startup +++\n"));

+	if (cp == v->start) {

+		co = d->cnfa->bos[(v->eflags&REG_NOTBOL) ? 0 : 1];

+		FDEBUG(("color %ld\n", (long)co));

+	} else {

+		co = GETCOLOR(cm, *(cp - 1));

+		FDEBUG(("char %c, color %ld\n", (char)*(cp-1), (long)co));

+	}

+	css = miss(v, d, css, co, cp, start);

+	if (css == NULL)

+		return NULL;

+	css->lastseen = cp;

+

+	/* main loop */

+	if (v->eflags&REG_FTRACE)

+		while (cp < realstop) {

+			FDEBUG(("+++ at c%d +++\n", css - d->ssets));

+			co = GETCOLOR(cm, *cp);

+			FDEBUG(("char %c, color %ld\n", (char)*cp, (long)co));

+			ss = css->outs[co];

+			if (ss == NULL) {

+				ss = miss(v, d, css, co, cp+1, start);

+				if (ss == NULL)

+					break;	/* NOTE BREAK OUT */

+			}

+			cp++;

+			ss->lastseen = cp;

+			css = ss;

+		}

+	else

+		while (cp < realstop) {

+			co = GETCOLOR(cm, *cp);

+			ss = css->outs[co];

+			if (ss == NULL) {

+				ss = miss(v, d, css, co, cp+1, start);

+				if (ss == NULL)

+					break;	/* NOTE BREAK OUT */

+			}

+			cp++;

+			ss->lastseen = cp;

+			css = ss;

+		}

+

+	/* shutdown */

+	FDEBUG(("+++ shutdown at c%d +++\n", css - d->ssets));

+	if (cp == v->stop && stop == v->stop) {

+		if (hitstopp != NULL)

+			*hitstopp = 1;

+		co = d->cnfa->eos[(v->eflags&REG_NOTEOL) ? 0 : 1];

+		FDEBUG(("color %ld\n", (long)co));

+		ss = miss(v, d, css, co, cp, start);

+		/* special case:  match ended at eol? */

+		if (ss != NULL && (ss->flags&POSTSTATE))

+			return cp;

+		else if (ss != NULL)

+			ss->lastseen = cp;	/* to be tidy */

+	}

+

+	/* find last match, if any */

+	post = d->lastpost;

+	for (ss = d->ssets, i = d->nssused; i > 0; ss++, i--)

+		if ((ss->flags&POSTSTATE) && post != ss->lastseen &&

+					(post == NULL || post < ss->lastseen))

+			post = ss->lastseen;

+	if (post != NULL)		/* found one */

+		return post - 1;

+

+	return NULL;

+}

+

+/*

+ - shortest - shortest-preferred matching engine

+ ^ static chr *shortest(struct vars *, struct dfa *, chr *, chr *, chr *,

+ ^ 	chr **, int *);

+ */

+static chr *			/* endpoint, or NULL */

+shortest(v, d, start, min, max, coldp, hitstopp)

+struct vars *v;

+struct dfa *d;

+chr *start;			/* where the match should start */

+chr *min;			/* match must end at or after here */

+chr *max;			/* match must end at or before here */

+chr **coldp;			/* store coldstart pointer here, if nonNULL */

+int *hitstopp;			/* record whether hit v->stop, if non-NULL */

+{

+	chr *cp;

+	chr *realmin = (min == v->stop) ? min : min + 1;

+	chr *realmax = (max == v->stop) ? max : max + 1;

+	color co;

+	struct sset *css;

+	struct sset *ss;

+	struct colormap *cm = d->cm;

+

+	/* initialize */

+	css = initialize(v, d, start);

+	cp = start;

+	if (hitstopp != NULL)

+		*hitstopp = 0;

+

+	/* startup */

+	FDEBUG(("--- startup ---\n"));

+	if (cp == v->start) {

+		co = d->cnfa->bos[(v->eflags&REG_NOTBOL) ? 0 : 1];

+		FDEBUG(("color %ld\n", (long)co));

+	} else {

+		co = GETCOLOR(cm, *(cp - 1));

+		FDEBUG(("char %c, color %ld\n", (char)*(cp-1), (long)co));

+	}

+	css = miss(v, d, css, co, cp, start);

+	if (css == NULL)

+		return NULL;

+	css->lastseen = cp;

+	ss = css;

+

+	/* main loop */

+	if (v->eflags&REG_FTRACE)

+		while (cp < realmax) {

+			FDEBUG(("--- at c%d ---\n", css - d->ssets));

+			co = GETCOLOR(cm, *cp);

+			FDEBUG(("char %c, color %ld\n", (char)*cp, (long)co));

+			ss = css->outs[co];

+			if (ss == NULL) {

+				ss = miss(v, d, css, co, cp+1, start);

+				if (ss == NULL)

+					break;	/* NOTE BREAK OUT */

+			}

+			cp++;

+			ss->lastseen = cp;

+			css = ss;

+			if ((ss->flags&POSTSTATE) && cp >= realmin)

+				break;		/* NOTE BREAK OUT */

+		}

+	else

+		while (cp < realmax) {

+			co = GETCOLOR(cm, *cp);

+			ss = css->outs[co];

+			if (ss == NULL) {

+				ss = miss(v, d, css, co, cp+1, start);

+				if (ss == NULL)

+					break;	/* NOTE BREAK OUT */

+			}

+			cp++;

+			ss->lastseen = cp;

+			css = ss;

+			if ((ss->flags&POSTSTATE) && cp >= realmin)

+				break;		/* NOTE BREAK OUT */

+		}

+

+	if (ss == NULL)

+		return NULL;

+

+	if (coldp != NULL)	/* report last no-progress state set, if any */

+		*coldp = lastcold(v, d);

+

+	if ((ss->flags&POSTSTATE) && cp > min) {

+		assert(cp >= realmin);

+		cp--;

+	} else if (cp == v->stop && max == v->stop) {

+		co = d->cnfa->eos[(v->eflags&REG_NOTEOL) ? 0 : 1];

+		FDEBUG(("color %ld\n", (long)co));

+		ss = miss(v, d, css, co, cp, start);

+		/* match might have ended at eol */

+		if ((ss == NULL || !(ss->flags&POSTSTATE)) && hitstopp != NULL)

+			*hitstopp = 1;

+	}

+

+	if (ss == NULL || !(ss->flags&POSTSTATE))

+		return NULL;

+

+	return cp;

+}

+

+/*

+ - lastcold - determine last point at which no progress had been made

+ ^ static chr *lastcold(struct vars *, struct dfa *);

+ */

+static chr *			/* endpoint, or NULL */

+lastcold(v, d)

+struct vars *v;

+struct dfa *d;

+{

+	struct sset *ss;

+	chr *nopr;

+	int i;

+

+	nopr = d->lastnopr;

+	if (nopr == NULL)

+		nopr = v->start;

+	for (ss = d->ssets, i = d->nssused; i > 0; ss++, i--)

+		if ((ss->flags&NOPROGRESS) && nopr < ss->lastseen)

+			nopr = ss->lastseen;

+	return nopr;

+}

+

+/*

+ - newdfa - set up a fresh DFA

+ ^ static struct dfa *newdfa(struct vars *, struct cnfa *,

+ ^ 	struct colormap *, struct smalldfa *);

+ */

+static struct dfa *

+newdfa(v, cnfa, cm, small)

+struct vars *v;

+struct cnfa *cnfa;

+struct colormap *cm;

+struct smalldfa *small;		/* preallocated space, may be NULL */

+{

+	struct dfa *d;

+	size_t nss = cnfa->nstates * 2;

+	int wordsper = (cnfa->nstates + UBITS - 1) / UBITS;

+	struct smalldfa *smallwas = small;

+

+	assert(cnfa != NULL && cnfa->nstates != 0);

+

+	if (nss <= FEWSTATES && cnfa->ncolors <= FEWCOLORS) {

+		assert(wordsper == 1);

+		if (small == NULL) {

+			small = (struct smalldfa *)MALLOC(

+						sizeof(struct smalldfa));

+			if (small == NULL) {

+				ERR(REG_ESPACE);

+				return NULL;

+			}

+		}

+		d = &small->dfa;

+		d->ssets = small->ssets;

+		d->statesarea = small->statesarea;

+		d->work = &d->statesarea[nss];

+		d->outsarea = small->outsarea;

+		d->incarea = small->incarea;

+		d->cptsmalloced = 0;

+		d->mallocarea = (smallwas == NULL) ? (char *)small : NULL;

+	} else {

+		d = (struct dfa *)MALLOC(sizeof(struct dfa));

+		if (d == NULL) {

+			ERR(REG_ESPACE);

+			return NULL;

+		}

+		d->ssets = (struct sset *)MALLOC(nss * sizeof(struct sset));

+		d->statesarea = (unsigned *)MALLOC((nss+WORK) * wordsper *

+							sizeof(unsigned));

+		d->work = &d->statesarea[nss * wordsper];

+		d->outsarea = (struct sset **)MALLOC(nss * cnfa->ncolors *

+							sizeof(struct sset *));

+		d->incarea = (struct arcp *)MALLOC(nss * cnfa->ncolors *

+							sizeof(struct arcp));

+		d->cptsmalloced = 1;

+		d->mallocarea = (char *)d;

+		if (d->ssets == NULL || d->statesarea == NULL ||

+				d->outsarea == NULL || d->incarea == NULL) {

+			freedfa(d);

+			ERR(REG_ESPACE);

+			return NULL;

+		}

+	}

+

+	d->nssets = (v->eflags&REG_SMALL) ? 7 : nss;

+	d->nssused = 0;

+	d->nstates = cnfa->nstates;

+	d->ncolors = cnfa->ncolors;

+	d->wordsper = wordsper;

+	d->cnfa = cnfa;

+	d->cm = cm;

+	d->lastpost = NULL;

+	d->lastnopr = NULL;

+	d->search = d->ssets;

+

+	/* initialization of sset fields is done as needed */

+

+	return d;

+}

+

+/*

+ - freedfa - free a DFA

+ ^ static VOID freedfa(struct dfa *);

+ */

+static VOID

+freedfa(d)

+struct dfa *d;

+{

+	if (d->cptsmalloced) {

+		if (d->ssets != NULL)

+			FREE(d->ssets);

+		if (d->statesarea != NULL)

+			FREE(d->statesarea);

+		if (d->outsarea != NULL)

+			FREE(d->outsarea);

+		if (d->incarea != NULL)

+			FREE(d->incarea);

+	}

+

+	if (d->mallocarea != NULL)

+		FREE(d->mallocarea);

+}

+

+/*

+ - hash - construct a hash code for a bitvector

+ * There are probably better ways, but they're more expensive.

+ ^ static unsigned hash(unsigned *, int);

+ */

+static unsigned

+hash(uv, n)

+unsigned *uv;

+int n;

+{

+	int i;

+	unsigned h;

+

+	h = 0;

+	for (i = 0; i < n; i++)

+		h ^= uv[i];

+	return h;

+}

+

+/*

+ - initialize - hand-craft a cache entry for startup, otherwise get ready

+ ^ static struct sset *initialize(struct vars *, struct dfa *, chr *);

+ */

+static struct sset *

+initialize(v, d, start)

+struct vars *v;			/* used only for debug flags */

+struct dfa *d;

+chr *start;

+{

+	struct sset *ss;

+	int i;

+

+	/* is previous one still there? */

+	if (d->nssused > 0 && (d->ssets[0].flags&STARTER))

+		ss = &d->ssets[0];

+	else {				/* no, must (re)build it */

+		ss = getvacant(v, d, start, start);

+		for (i = 0; i < d->wordsper; i++)

+			ss->states[i] = 0;

+		BSET(ss->states, d->cnfa->pre);

+		ss->hash = HASH(ss->states, d->wordsper);

+		assert(d->cnfa->pre != d->cnfa->post);

+		ss->flags = STARTER|LOCKED|NOPROGRESS;

+		/* lastseen dealt with below */

+	}

+

+	for (i = 0; i < d->nssused; i++)

+		d->ssets[i].lastseen = NULL;

+	ss->lastseen = start;		/* maybe untrue, but harmless */

+	d->lastpost = NULL;

+	d->lastnopr = NULL;

+	return ss;

+}

+

+/*

+ - miss - handle a cache miss

+ ^ static struct sset *miss(struct vars *, struct dfa *, struct sset *,

+ ^ 	pcolor, chr *, chr *);

+ */

+static struct sset *		/* NULL if goes to empty set */

+miss(v, d, css, co, cp, start)

+struct vars *v;			/* used only for debug flags */

+struct dfa *d;

+struct sset *css;

+pcolor co;

+chr *cp;			/* next chr */

+chr *start;			/* where the attempt got started */

+{

+	struct cnfa *cnfa = d->cnfa;

+	int i;

+	unsigned h;

+	struct carc *ca;

+	struct sset *p;

+	int ispost;

+	int noprogress;

+	int gotstate;

+	int dolacons;

+	int sawlacons;

+

+	/* for convenience, we can be called even if it might not be a miss */

+	if (css->outs[co] != NULL) {

+		FDEBUG(("hit\n"));

+		return css->outs[co];

+	}

+	FDEBUG(("miss\n"));

+

+	/* first, what set of states would we end up in? */

+	for (i = 0; i < d->wordsper; i++)

+		d->work[i] = 0;

+	ispost = 0;

+	noprogress = 1;

+	gotstate = 0;

+	for (i = 0; i < d->nstates; i++)

+		if (ISBSET(css->states, i))

+			for (ca = cnfa->states[i]+1; ca->co != COLORLESS; ca++)

+				if (ca->co == co) {

+					BSET(d->work, ca->to);

+					gotstate = 1;

+					if (ca->to == cnfa->post)

+						ispost = 1;

+					if (!cnfa->states[ca->to]->co)

+						noprogress = 0;

+					FDEBUG(("%d -> %d\n", i, ca->to));

+				}

+	dolacons = (gotstate) ? (cnfa->flags&HASLACONS) : 0;

+	sawlacons = 0;

+	while (dolacons) {		/* transitive closure */

+		dolacons = 0;

+		for (i = 0; i < d->nstates; i++)

+			if (ISBSET(d->work, i))

+				for (ca = cnfa->states[i]+1; ca->co != COLORLESS;

+									ca++) {

+					if (ca->co <= cnfa->ncolors)

+						continue; /* NOTE CONTINUE */

+					sawlacons = 1;

+					if (ISBSET(d->work, ca->to))

+						continue; /* NOTE CONTINUE */

+					if (!lacon(v, cnfa, cp, ca->co))

+						continue; /* NOTE CONTINUE */

+					BSET(d->work, ca->to);

+					dolacons = 1;

+					if (ca->to == cnfa->post)

+						ispost = 1;

+					if (!cnfa->states[ca->to]->co)

+						noprogress = 0;

+					FDEBUG(("%d :> %d\n", i, ca->to));

+				}

+	}

+	if (!gotstate)

+		return NULL;

+	h = HASH(d->work, d->wordsper);

+

+	/* next, is that in the cache? */

+	for (p = d->ssets, i = d->nssused; i > 0; p++, i--)

+		if (HIT(h, d->work, p, d->wordsper)) {

+			FDEBUG(("cached c%d\n", p - d->ssets));

+			break;			/* NOTE BREAK OUT */

+		}

+	if (i == 0) {		/* nope, need a new cache entry */

+		p = getvacant(v, d, cp, start);

+		assert(p != css);

+		for (i = 0; i < d->wordsper; i++)

+			p->states[i] = d->work[i];

+		p->hash = h;

+		p->flags = (ispost) ? POSTSTATE : 0;

+		if (noprogress)

+			p->flags |= NOPROGRESS;

+		/* lastseen to be dealt with by caller */

+	}

+

+	if (!sawlacons) {		/* lookahead conds. always cache miss */

+		FDEBUG(("c%d[%d]->%d\n", css - d->ssets, co, p - d->ssets));

+		css->outs[co] = p;

+		css->inchain[co] = p->ins;

+		p->ins.ss = css;

+		p->ins.co = (color)co;

+	}

+	return p;

+}

+

+/*

+ - lacon - lookahead-constraint checker for miss()

+ ^ static int lacon(struct vars *, struct cnfa *, chr *, pcolor);

+ */

+static int			/* predicate:  constraint satisfied? */

+lacon(v, pcnfa, cp, co)

+struct vars *v;

+struct cnfa *pcnfa;		/* parent cnfa */

+chr *cp;

+pcolor co;			/* "color" of the lookahead constraint */

+{

+	int n;

+	struct subre *sub;

+	struct dfa *d;

+	struct smalldfa sd;

+	chr *end;

+

+	n = co - pcnfa->ncolors;

+	assert(n < v->g->nlacons && v->g->lacons != NULL);

+	FDEBUG(("=== testing lacon %d\n", n));

+	sub = &v->g->lacons[n];

+	d = newdfa(v, &sub->cnfa, &v->g->cmap, &sd);

+	if (d == NULL) {

+		ERR(REG_ESPACE);

+		return 0;

+	}

+	end = longest(v, d, cp, v->stop, (int *)NULL);

+	freedfa(d);

+	FDEBUG(("=== lacon %d match %d\n", n, (end != NULL)));

+	return (sub->subno) ? (end != NULL) : (end == NULL);

+}

+

+/*

+ - getvacant - get a vacant state set

+ * This routine clears out the inarcs and outarcs, but does not otherwise

+ * clear the innards of the state set -- that's up to the caller.

+ ^ static struct sset *getvacant(struct vars *, struct dfa *, chr *, chr *);

+ */

+static struct sset *

+getvacant(v, d, cp, start)

+struct vars *v;			/* used only for debug flags */

+struct dfa *d;

+chr *cp;

+chr *start;

+{

+	int i;

+	struct sset *ss;

+	struct sset *p;

+	struct arcp ap;

+	struct arcp lastap;

+	color co;

+

+	ss = pickss(v, d, cp, start);

+	assert(!(ss->flags&LOCKED));

+

+	/* clear out its inarcs, including self-referential ones */

+	ap = ss->ins;

+	while ((p = ap.ss) != NULL) {

+		co = ap.co;

+		FDEBUG(("zapping c%d's %ld outarc\n", p - d->ssets, (long)co));

+		p->outs[co] = NULL;

+		ap = p->inchain[co];

+		p->inchain[co].ss = NULL;	/* paranoia */

+	}

+	ss->ins.ss = NULL;

+

+	/* take it off the inarc chains of the ssets reached by its outarcs */

+	for (i = 0; i < d->ncolors; i++) {

+		p = ss->outs[i];

+		assert(p != ss);		/* not self-referential */

+		if (p == NULL)

+			continue;		/* NOTE CONTINUE */

+		FDEBUG(("del outarc %d from c%d's in chn\n", i, p - d->ssets));

+		if (p->ins.ss == ss && p->ins.co == i)

+			p->ins = ss->inchain[i];

+		else {

+			assert(p->ins.ss != NULL);

+			for (ap = p->ins; ap.ss != NULL &&

+						!(ap.ss == ss && ap.co == i);

+						ap = ap.ss->inchain[ap.co])

+				lastap = ap;

+			assert(ap.ss != NULL);

+			lastap.ss->inchain[lastap.co] = ss->inchain[i];

+		}

+		ss->outs[i] = NULL;

+		ss->inchain[i].ss = NULL;

+	}

+

+	/* if ss was a success state, may need to remember location */

+	if ((ss->flags&POSTSTATE) && ss->lastseen != d->lastpost &&

+			(d->lastpost == NULL || d->lastpost < ss->lastseen))

+		d->lastpost = ss->lastseen;

+

+	/* likewise for a no-progress state */

+	if ((ss->flags&NOPROGRESS) && ss->lastseen != d->lastnopr &&

+			(d->lastnopr == NULL || d->lastnopr < ss->lastseen))

+		d->lastnopr = ss->lastseen;

+

+	return ss;

+}

+

+/*

+ - pickss - pick the next stateset to be used

+ ^ static struct sset *pickss(struct vars *, struct dfa *, chr *, chr *);

+ */

+static struct sset *

+pickss(v, d, cp, start)

+struct vars *v;			/* used only for debug flags */

+struct dfa *d;

+chr *cp;

+chr *start;

+{

+	int i;

+	struct sset *ss;

+	struct sset *end;

+	chr *ancient;

+

+	/* shortcut for cases where cache isn't full */

+	if (d->nssused < d->nssets) {

+		i = d->nssused;

+		d->nssused++;

+		ss = &d->ssets[i];

+		FDEBUG(("new c%d\n", i));

+		/* set up innards */

+		ss->states = &d->statesarea[i * d->wordsper];

+		ss->flags = 0;

+		ss->ins.ss = NULL;

+		ss->ins.co = WHITE;		/* give it some value */

+		ss->outs = &d->outsarea[i * d->ncolors];

+		ss->inchain = &d->incarea[i * d->ncolors];

+		for (i = 0; i < d->ncolors; i++) {

+			ss->outs[i] = NULL;

+			ss->inchain[i].ss = NULL;

+		}

+		return ss;

+	}

+

+	/* look for oldest, or old enough anyway */

+	if (cp - start > d->nssets*2/3)		/* oldest 33% are expendable */

+		ancient = cp - d->nssets*2/3;

+	else

+		ancient = start;

+	for (ss = d->search, end = &d->ssets[d->nssets]; ss < end; ss++)

+		if ((ss->lastseen == NULL || ss->lastseen < ancient) &&

+							!(ss->flags&LOCKED)) {

+			d->search = ss + 1;

+			FDEBUG(("replacing c%d\n", ss - d->ssets));

+			return ss;

+		}

+	for (ss = d->ssets, end = d->search; ss < end; ss++)

+		if ((ss->lastseen == NULL || ss->lastseen < ancient) &&

+							!(ss->flags&LOCKED)) {

+			d->search = ss + 1;

+			FDEBUG(("replacing c%d\n", ss - d->ssets));

+			return ss;

+		}

+

+	/* nobody's old enough?!? -- something's really wrong */

+	FDEBUG(("can't find victim to replace!\n"));

+	assert(NOTREACHED);

+	ERR(REG_ASSERT);

+	return d->ssets;

+}