xref: /freebsd/usr.bin/gprof/arcs.c (revision 42c159fe388a3765f69860c84183700af37aca8a)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 #if 0
36 static char sccsid[] = "@(#)arcs.c	8.1 (Berkeley) 6/6/93";
37 #endif
38 static const char rcsid[] =
39   "$FreeBSD$";
40 #endif /* not lint */
41 
42 #include <err.h>
43 #include "gprof.h"
44 
45 #ifdef DEBUG
46 int visited;
47 int viable;
48 int newcycle;
49 int oldcycle;
50 #endif DEBUG
51 
52     /*
53      *	add (or just increment) an arc
54      */
55 addarc( parentp , childp , count )
56     nltype	*parentp;
57     nltype	*childp;
58     long	count;
59 {
60     arctype		*arcp;
61 
62 #   ifdef DEBUG
63 	if ( debug & TALLYDEBUG ) {
64 	    printf( "[addarc] %ld arcs from %s to %s\n" ,
65 		    count , parentp -> name , childp -> name );
66 	}
67 #   endif DEBUG
68     arcp = arclookup( parentp , childp );
69     if ( arcp != 0 ) {
70 	    /*
71 	     *	a hit:  just increment the count.
72 	     */
73 #	ifdef DEBUG
74 	    if ( debug & TALLYDEBUG ) {
75 		printf( "[tally] hit %ld += %ld\n" ,
76 			arcp -> arc_count , count );
77 	    }
78 #	endif DEBUG
79 	arcp -> arc_count += count;
80 	return;
81     }
82     arcp = (arctype *)calloc( 1 , sizeof *arcp );
83     arcp -> arc_parentp = parentp;
84     arcp -> arc_childp = childp;
85     arcp -> arc_count = count;
86 	/*
87 	 *	prepend this child to the children of this parent
88 	 */
89     arcp -> arc_childlist = parentp -> children;
90     parentp -> children = arcp;
91 	/*
92 	 *	prepend this parent to the parents of this child
93 	 */
94     arcp -> arc_parentlist = childp -> parents;
95     childp -> parents = arcp;
96 }
97 
98     /*
99      *	the code below topologically sorts the graph (collapsing cycles),
100      *	and propagates time bottom up and flags top down.
101      */
102 
103     /*
104      *	the topologically sorted name list pointers
105      */
106 nltype	**topsortnlp;
107 
108 topcmp( npp1 , npp2 )
109     nltype	**npp1;
110     nltype	**npp2;
111 {
112     return (*npp1) -> toporder - (*npp2) -> toporder;
113 }
114 
115 nltype **
116 doarcs()
117 {
118     nltype	*parentp, **timesortnlp;
119     arctype	*arcp;
120     long	index;
121     long	pass;
122 
123 	/*
124 	 *	initialize various things:
125 	 *	    zero out child times.
126 	 *	    count self-recursive calls.
127 	 *	    indicate that nothing is on cycles.
128 	 */
129     for ( parentp = nl ; parentp < npe ; parentp++ ) {
130 	parentp -> childtime = 0.0;
131 	arcp = arclookup( parentp , parentp );
132 	if ( arcp != 0 ) {
133 	    parentp -> ncall -= arcp -> arc_count;
134 	    parentp -> selfcalls = arcp -> arc_count;
135 	} else {
136 	    parentp -> selfcalls = 0;
137 	}
138 	parentp -> npropcall = parentp -> ncall;
139 	parentp -> propfraction = 0.0;
140 	parentp -> propself = 0.0;
141 	parentp -> propchild = 0.0;
142 	parentp -> printflag = FALSE;
143 	parentp -> toporder = DFN_NAN;
144 	parentp -> cycleno = 0;
145 	parentp -> cyclehead = parentp;
146 	parentp -> cnext = 0;
147 	if ( cflag ) {
148 	    findcall( parentp , parentp -> value , (parentp+1) -> value );
149 	}
150     }
151     for ( pass = 1 ; ; pass++ ) {
152 	    /*
153 	     *	topologically order things
154 	     *	if any node is unnumbered,
155 	     *	    number it and any of its descendents.
156 	     */
157 	for ( dfn_init() , parentp = nl ; parentp < npe ; parentp++ ) {
158 	    if ( parentp -> toporder == DFN_NAN ) {
159 		dfn( parentp );
160 	    }
161 	}
162 	    /*
163 	     *	link together nodes on the same cycle
164 	     */
165 	cyclelink();
166 	    /*
167 	     *	if no cycles to break up, proceed
168 	     */
169 	if ( ! Cflag )
170 	    break;
171 	    /*
172 	     *	analyze cycles to determine breakup
173 	     */
174 #	ifdef DEBUG
175 	    if ( debug & BREAKCYCLE ) {
176 		printf("[doarcs] pass %ld, cycle(s) %d\n" , pass , ncycle );
177 	    }
178 #	endif DEBUG
179 	if ( pass == 1 ) {
180 	    printf( "\n\n%s %s\n%s %d:\n" ,
181 		"The following arcs were deleted" ,
182 		"from the propagation calculation" ,
183 		"to reduce the maximum cycle size to", cyclethreshold );
184 	}
185 	if ( cycleanalyze() )
186 	    break;
187 	free ( cyclenl );
188 	ncycle = 0;
189 	for ( parentp = nl ; parentp < npe ; parentp++ ) {
190 	    parentp -> toporder = DFN_NAN;
191 	    parentp -> cycleno = 0;
192 	    parentp -> cyclehead = parentp;
193 	    parentp -> cnext = 0;
194 	}
195     }
196     if ( pass > 1 ) {
197 	printf( "\f\n" );
198     } else {
199 	printf( "\tNone\n\n" );
200     }
201 	/*
202 	 *	Sort the symbol table in reverse topological order
203 	 */
204     topsortnlp = (nltype **) calloc( nname , sizeof(nltype *) );
205     if ( topsortnlp == (nltype **) 0 ) {
206 	fprintf( stderr , "[doarcs] ran out of memory for topo sorting\n" );
207     }
208     for ( index = 0 ; index < nname ; index += 1 ) {
209 	topsortnlp[ index ] = &nl[ index ];
210     }
211     qsort( topsortnlp , nname , sizeof(nltype *) , topcmp );
212 #   ifdef DEBUG
213 	if ( debug & DFNDEBUG ) {
214 	    printf( "[doarcs] topological sort listing\n" );
215 	    for ( index = 0 ; index < nname ; index += 1 ) {
216 		printf( "[doarcs] " );
217 		printf( "%d:" , topsortnlp[ index ] -> toporder );
218 		printname( topsortnlp[ index ] );
219 		printf( "\n" );
220 	    }
221 	}
222 #   endif DEBUG
223 	/*
224 	 *	starting from the topological top,
225 	 *	propagate print flags to children.
226 	 *	also, calculate propagation fractions.
227 	 *	this happens before time propagation
228 	 *	since time propagation uses the fractions.
229 	 */
230     doflags();
231 	/*
232 	 *	starting from the topological bottom,
233 	 *	propogate children times up to parents.
234 	 */
235     dotime();
236 	/*
237 	 *	Now, sort by propself + propchild.
238 	 *	sorting both the regular function names
239 	 *	and cycle headers.
240 	 */
241     timesortnlp = (nltype **) calloc( nname + ncycle , sizeof(nltype *) );
242     if ( timesortnlp == (nltype **) 0 ) {
243 	warnx("ran out of memory for sorting");
244     }
245     for ( index = 0 ; index < nname ; index++ ) {
246 	timesortnlp[index] = &nl[index];
247     }
248     for ( index = 1 ; index <= ncycle ; index++ ) {
249 	timesortnlp[nname+index-1] = &cyclenl[index];
250     }
251     qsort( timesortnlp , nname + ncycle , sizeof(nltype *) , totalcmp );
252     for ( index = 0 ; index < nname + ncycle ; index++ ) {
253 	timesortnlp[ index ] -> index = index + 1;
254     }
255     return( timesortnlp );
256 }
257 
258 dotime()
259 {
260     int	index;
261 
262     cycletime();
263     for ( index = 0 ; index < nname ; index += 1 ) {
264 	timepropagate( topsortnlp[ index ] );
265     }
266 }
267 
268 timepropagate( parentp )
269     nltype	*parentp;
270 {
271     arctype	*arcp;
272     nltype	*childp;
273     double	share;
274     double	propshare;
275 
276     if ( parentp -> propfraction == 0.0 ) {
277 	return;
278     }
279 	/*
280 	 *	gather time from children of this parent.
281 	 */
282     for ( arcp = parentp -> children ; arcp ; arcp = arcp -> arc_childlist ) {
283 	childp = arcp -> arc_childp;
284 	if ( arcp -> arc_flags & DEADARC ) {
285 	    continue;
286 	}
287 	if ( arcp -> arc_count == 0 ) {
288 	    continue;
289 	}
290 	if ( childp == parentp ) {
291 	    continue;
292 	}
293 	if ( childp -> propfraction == 0.0 ) {
294 	    continue;
295 	}
296 	if ( childp -> cyclehead != childp ) {
297 	    if ( parentp -> cycleno == childp -> cycleno ) {
298 		continue;
299 	    }
300 	    if ( parentp -> toporder <= childp -> toporder ) {
301 		fprintf( stderr , "[propagate] toporder botches\n" );
302 	    }
303 	    childp = childp -> cyclehead;
304 	} else {
305 	    if ( parentp -> toporder <= childp -> toporder ) {
306 		fprintf( stderr , "[propagate] toporder botches\n" );
307 		continue;
308 	    }
309 	}
310 	if ( childp -> npropcall == 0 ) {
311 	    continue;
312 	}
313 	    /*
314 	     *	distribute time for this arc
315 	     */
316 	arcp -> arc_time = childp -> time
317 			        * ( ( (double) arcp -> arc_count ) /
318 				    ( (double) childp -> npropcall ) );
319 	arcp -> arc_childtime = childp -> childtime
320 			        * ( ( (double) arcp -> arc_count ) /
321 				    ( (double) childp -> npropcall ) );
322 	share = arcp -> arc_time + arcp -> arc_childtime;
323 	parentp -> childtime += share;
324 	    /*
325 	     *	( 1 - propfraction ) gets lost along the way
326 	     */
327 	propshare = parentp -> propfraction * share;
328 	    /*
329 	     *	fix things for printing
330 	     */
331 	parentp -> propchild += propshare;
332 	arcp -> arc_time *= parentp -> propfraction;
333 	arcp -> arc_childtime *= parentp -> propfraction;
334 	    /*
335 	     *	add this share to the parent's cycle header, if any.
336 	     */
337 	if ( parentp -> cyclehead != parentp ) {
338 	    parentp -> cyclehead -> childtime += share;
339 	    parentp -> cyclehead -> propchild += propshare;
340 	}
341 #	ifdef DEBUG
342 	    if ( debug & PROPDEBUG ) {
343 		printf( "[dotime] child \t" );
344 		printname( childp );
345 		printf( " with %f %f %ld/%ld\n" ,
346 			childp -> time , childp -> childtime ,
347 			arcp -> arc_count , childp -> npropcall );
348 		printf( "[dotime] parent\t" );
349 		printname( parentp );
350 		printf( "\n[dotime] share %f\n" , share );
351 	    }
352 #	endif DEBUG
353     }
354 }
355 
356 cyclelink()
357 {
358     register nltype	*nlp;
359     register nltype	*cyclenlp;
360     int			cycle;
361     nltype		*memberp;
362     arctype		*arcp;
363 
364 	/*
365 	 *	Count the number of cycles, and initialze the cycle lists
366 	 */
367     ncycle = 0;
368     for ( nlp = nl ; nlp < npe ; nlp++ ) {
369 	    /*
370 	     *	this is how you find unattached cycles
371 	     */
372 	if ( nlp -> cyclehead == nlp && nlp -> cnext != 0 ) {
373 	    ncycle += 1;
374 	}
375     }
376 	/*
377 	 *	cyclenl is indexed by cycle number:
378 	 *	i.e. it is origin 1, not origin 0.
379 	 */
380     cyclenl = (nltype *) calloc( ncycle + 1 , sizeof( nltype ) );
381     if ( cyclenl == 0 ) {
382 	warnx("no room for %d bytes of cycle headers",
383 		   ( ncycle + 1 ) * sizeof( nltype ) );
384 	done();
385     }
386 	/*
387 	 *	now link cycles to true cycleheads,
388 	 *	number them, accumulate the data for the cycle
389 	 */
390     cycle = 0;
391     for ( nlp = nl ; nlp < npe ; nlp++ ) {
392 	if ( !( nlp -> cyclehead == nlp && nlp -> cnext != 0 ) ) {
393 	    continue;
394 	}
395 	cycle += 1;
396 	cyclenlp = &cyclenl[cycle];
397         cyclenlp -> name = 0;		/* the name */
398         cyclenlp -> value = 0;		/* the pc entry point */
399         cyclenlp -> time = 0.0;		/* ticks in this routine */
400         cyclenlp -> childtime = 0.0;	/* cumulative ticks in children */
401 	cyclenlp -> ncall = 0;		/* how many times called */
402 	cyclenlp -> selfcalls = 0;	/* how many calls to self */
403 	cyclenlp -> propfraction = 0.0;	/* what % of time propagates */
404 	cyclenlp -> propself = 0.0;	/* how much self time propagates */
405 	cyclenlp -> propchild = 0.0;	/* how much child time propagates */
406 	cyclenlp -> printflag = TRUE;	/* should this be printed? */
407 	cyclenlp -> index = 0;		/* index in the graph list */
408 	cyclenlp -> toporder = DFN_NAN;	/* graph call chain top-sort order */
409 	cyclenlp -> cycleno = cycle;	/* internal number of cycle on */
410 	cyclenlp -> cyclehead = cyclenlp;	/* pointer to head of cycle */
411 	cyclenlp -> cnext = nlp;	/* pointer to next member of cycle */
412 	cyclenlp -> parents = 0;	/* list of caller arcs */
413 	cyclenlp -> children = 0;	/* list of callee arcs */
414 #	ifdef DEBUG
415 	    if ( debug & CYCLEDEBUG ) {
416 		printf( "[cyclelink] " );
417 		printname( nlp );
418 		printf( " is the head of cycle %d\n" , cycle );
419 	    }
420 #	endif DEBUG
421 	    /*
422 	     *	link members to cycle header
423 	     */
424 	for ( memberp = nlp ; memberp ; memberp = memberp -> cnext ) {
425 	    memberp -> cycleno = cycle;
426 	    memberp -> cyclehead = cyclenlp;
427 	}
428 	    /*
429 	     *	count calls from outside the cycle
430 	     *	and those among cycle members
431 	     */
432 	for ( memberp = nlp ; memberp ; memberp = memberp -> cnext ) {
433 	    for ( arcp=memberp->parents ; arcp ; arcp=arcp->arc_parentlist ) {
434 		if ( arcp -> arc_parentp == memberp ) {
435 		    continue;
436 		}
437 		if ( arcp -> arc_parentp -> cycleno == cycle ) {
438 		    cyclenlp -> selfcalls += arcp -> arc_count;
439 		} else {
440 		    cyclenlp -> npropcall += arcp -> arc_count;
441 		}
442 	    }
443 	}
444     }
445 }
446 
447     /*
448      *	analyze cycles to determine breakup
449      */
450 cycleanalyze()
451 {
452     arctype	**cyclestack;
453     arctype	**stkp;
454     arctype	**arcpp;
455     arctype	**endlist;
456     arctype	*arcp;
457     nltype	*nlp;
458     cltype	*clp;
459     bool	ret;
460     bool	done;
461     int		size;
462     int		cycleno;
463 
464 	/*
465 	 *	calculate the size of the cycle, and find nodes that
466 	 *	exit the cycle as they are desirable targets to cut
467 	 *	some of their parents
468 	 */
469     for ( done = TRUE , cycleno = 1 ; cycleno <= ncycle ; cycleno++ ) {
470 	size = 0;
471 	for (nlp = cyclenl[ cycleno ] . cnext; nlp; nlp = nlp -> cnext) {
472 	    size += 1;
473 	    nlp -> parentcnt = 0;
474 	    nlp -> flags &= ~HASCYCLEXIT;
475 	    for ( arcp = nlp -> parents; arcp; arcp = arcp -> arc_parentlist ) {
476 		nlp -> parentcnt += 1;
477 		if ( arcp -> arc_parentp -> cycleno != cycleno )
478 		    nlp -> flags |= HASCYCLEXIT;
479 	    }
480 	}
481 	if ( size <= cyclethreshold )
482 	    continue;
483 	done = FALSE;
484         cyclestack = (arctype **) calloc( size + 1 , sizeof( arctype *) );
485 	if ( cyclestack == 0 ) {
486 	    warnx("no room for %d bytes of cycle stack",
487 			   ( size + 1 ) * sizeof( arctype * ) );
488 	    return;
489 	}
490 #	ifdef DEBUG
491 	    if ( debug & BREAKCYCLE ) {
492 		printf( "[cycleanalyze] starting cycle %d of %d, size %d\n" ,
493 		    cycleno , ncycle , size );
494 	    }
495 #	endif DEBUG
496 	for ( nlp = cyclenl[ cycleno ] . cnext ; nlp ; nlp = nlp -> cnext ) {
497 	    stkp = &cyclestack[0];
498 	    nlp -> flags |= CYCLEHEAD;
499 	    ret = descend ( nlp , cyclestack , stkp );
500 	    nlp -> flags &= ~CYCLEHEAD;
501 	    if ( ret == FALSE )
502 		break;
503 	}
504 	free( cyclestack );
505 	if ( cyclecnt > 0 ) {
506 	    compresslist();
507 	    for ( clp = cyclehead ; clp ; ) {
508 		endlist = &clp -> list[ clp -> size ];
509 		for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ )
510 		    (*arcpp) -> arc_cyclecnt--;
511 		cyclecnt--;
512 		clp = clp -> next;
513 		free( clp );
514 	    }
515 	    cyclehead = 0;
516 	}
517     }
518 #   ifdef DEBUG
519 	if ( debug & BREAKCYCLE ) {
520 	    printf("%s visited %d, viable %d, newcycle %d, oldcycle %d\n",
521 		"[doarcs]" , visited , viable , newcycle , oldcycle);
522 	}
523 #   endif DEBUG
524     return( done );
525 }
526 
527 descend( node , stkstart , stkp )
528     nltype	*node;
529     arctype	**stkstart;
530     arctype	**stkp;
531 {
532     arctype	*arcp;
533     bool	ret;
534 
535     for ( arcp = node -> children ; arcp ; arcp = arcp -> arc_childlist ) {
536 #	ifdef DEBUG
537 	    visited++;
538 #	endif DEBUG
539 	if ( arcp -> arc_childp -> cycleno != node -> cycleno
540 	    || ( arcp -> arc_childp -> flags & VISITED )
541 	    || ( arcp -> arc_flags & DEADARC ) )
542 	    continue;
543 #	ifdef DEBUG
544 	    viable++;
545 #	endif DEBUG
546 	*stkp = arcp;
547 	if ( arcp -> arc_childp -> flags & CYCLEHEAD ) {
548 	    if ( addcycle( stkstart , stkp ) == FALSE )
549 		return( FALSE );
550 	    continue;
551 	}
552 	arcp -> arc_childp -> flags |= VISITED;
553 	ret = descend( arcp -> arc_childp , stkstart , stkp + 1 );
554 	arcp -> arc_childp -> flags &= ~VISITED;
555 	if ( ret == FALSE )
556 	    return( FALSE );
557     }
558 }
559 
560 addcycle( stkstart , stkend )
561     arctype	**stkstart;
562     arctype	**stkend;
563 {
564     arctype	**arcpp;
565     arctype	**stkloc;
566     arctype	**stkp;
567     arctype	**endlist;
568     arctype	*minarc;
569     arctype	*arcp;
570     cltype	*clp;
571     int		size;
572 
573     size = stkend - stkstart + 1;
574     if ( size <= 1 )
575 	return( TRUE );
576     for ( arcpp = stkstart , minarc = *arcpp ; arcpp <= stkend ; arcpp++ ) {
577 	if ( *arcpp > minarc )
578 	    continue;
579 	minarc = *arcpp;
580 	stkloc = arcpp;
581     }
582     for ( clp = cyclehead ; clp ; clp = clp -> next ) {
583 	if ( clp -> size != size )
584 	    continue;
585 	stkp = stkloc;
586 	endlist = &clp -> list[ size ];
587 	for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ ) {
588 	    if ( *stkp++ != *arcpp )
589 		break;
590 	    if ( stkp > stkend )
591 		stkp = stkstart;
592 	}
593 	if ( arcpp == endlist ) {
594 #	    ifdef DEBUG
595 		oldcycle++;
596 #	    endif DEBUG
597 	    return( TRUE );
598 	}
599     }
600     clp = (cltype *)
601 	calloc( 1 , sizeof ( cltype ) + ( size - 1 ) * sizeof( arctype * ) );
602     if ( clp == 0 ) {
603 	warnx("no room for %d bytes of subcycle storage",
604 	    sizeof ( cltype ) + ( size - 1 ) * sizeof( arctype * ) );
605 	return( FALSE );
606     }
607     stkp = stkloc;
608     endlist = &clp -> list[ size ];
609     for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ ) {
610 	arcp = *arcpp = *stkp++;
611 	if ( stkp > stkend )
612 	    stkp = stkstart;
613 	arcp -> arc_cyclecnt++;
614 	if ( ( arcp -> arc_flags & ONLIST ) == 0 ) {
615 	    arcp -> arc_flags |= ONLIST;
616 	    arcp -> arc_next = archead;
617 	    archead = arcp;
618 	}
619     }
620     clp -> size = size;
621     clp -> next = cyclehead;
622     cyclehead = clp;
623 #   ifdef DEBUG
624 	newcycle++;
625 	if ( debug & SUBCYCLELIST ) {
626 	    printsubcycle( clp );
627 	}
628 #   endif DEBUG
629     cyclecnt++;
630     if ( cyclecnt >= CYCLEMAX )
631 	return( FALSE );
632     return( TRUE );
633 }
634 
635 compresslist()
636 {
637     cltype	*clp;
638     cltype	**prev;
639     arctype	**arcpp;
640     arctype	**endlist;
641     arctype	*arcp;
642     arctype	*maxarcp;
643     arctype	*maxexitarcp;
644     arctype	*maxwithparentarcp;
645     arctype	*maxnoparentarcp;
646     int		maxexitcnt;
647     int		maxwithparentcnt;
648     int		maxnoparentcnt;
649 #   ifdef DEBUG
650 	const char	*type;
651 #   endif DEBUG
652 
653     maxexitcnt = 0;
654     maxwithparentcnt = 0;
655     maxnoparentcnt = 0;
656     for ( endlist = &archead , arcp = archead ; arcp ; ) {
657 	if ( arcp -> arc_cyclecnt == 0 ) {
658 	    arcp -> arc_flags &= ~ONLIST;
659 	    *endlist = arcp -> arc_next;
660 	    arcp -> arc_next = 0;
661 	    arcp = *endlist;
662 	    continue;
663 	}
664 	if ( arcp -> arc_childp -> flags & HASCYCLEXIT ) {
665 	    if ( arcp -> arc_cyclecnt > maxexitcnt ||
666 		( arcp -> arc_cyclecnt == maxexitcnt &&
667 		arcp -> arc_cyclecnt < maxexitarcp -> arc_count ) ) {
668 		maxexitcnt = arcp -> arc_cyclecnt;
669 		maxexitarcp = arcp;
670 	    }
671 	} else if ( arcp -> arc_childp -> parentcnt > 1 ) {
672 	    if ( arcp -> arc_cyclecnt > maxwithparentcnt ||
673 		( arcp -> arc_cyclecnt == maxwithparentcnt &&
674 		arcp -> arc_cyclecnt < maxwithparentarcp -> arc_count ) ) {
675 		maxwithparentcnt = arcp -> arc_cyclecnt;
676 		maxwithparentarcp = arcp;
677 	    }
678 	} else {
679 	    if ( arcp -> arc_cyclecnt > maxnoparentcnt ||
680 		( arcp -> arc_cyclecnt == maxnoparentcnt &&
681 		arcp -> arc_cyclecnt < maxnoparentarcp -> arc_count ) ) {
682 		maxnoparentcnt = arcp -> arc_cyclecnt;
683 		maxnoparentarcp = arcp;
684 	    }
685 	}
686 	endlist = &arcp -> arc_next;
687 	arcp = arcp -> arc_next;
688     }
689     if ( maxexitcnt > 0 ) {
690 	/*
691 	 *	first choice is edge leading to node with out-of-cycle parent
692 	 */
693 	maxarcp = maxexitarcp;
694 #	ifdef DEBUG
695 	    type = "exit";
696 #	endif DEBUG
697     } else if ( maxwithparentcnt > 0 ) {
698 	/*
699 	 *	second choice is edge leading to node with at least one
700 	 *	other in-cycle parent
701 	 */
702 	maxarcp = maxwithparentarcp;
703 #	ifdef DEBUG
704 	    type = "internal";
705 #	endif DEBUG
706     } else {
707 	/*
708 	 *	last choice is edge leading to node with only this arc as
709 	 *	a parent (as it will now be orphaned)
710 	 */
711 	maxarcp = maxnoparentarcp;
712 #	ifdef DEBUG
713 	    type = "orphan";
714 #	endif DEBUG
715     }
716     maxarcp -> arc_flags |= DEADARC;
717     maxarcp -> arc_childp -> parentcnt -= 1;
718     maxarcp -> arc_childp -> npropcall -= maxarcp -> arc_count;
719 #   ifdef DEBUG
720 	if ( debug & BREAKCYCLE ) {
721 	    printf( "%s delete %s arc: %s (%ld) -> %s from %u cycle(s)\n" ,
722 		"[compresslist]" , type , maxarcp -> arc_parentp -> name ,
723 		maxarcp -> arc_count , maxarcp -> arc_childp -> name ,
724 		maxarcp -> arc_cyclecnt );
725 	}
726 #   endif DEBUG
727     printf( "\t%s to %s with %ld calls\n" , maxarcp -> arc_parentp -> name ,
728 	maxarcp -> arc_childp -> name , maxarcp -> arc_count );
729     prev = &cyclehead;
730     for ( clp = cyclehead ; clp ; ) {
731 	endlist = &clp -> list[ clp -> size ];
732 	for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ )
733 	    if ( (*arcpp) -> arc_flags & DEADARC )
734 		break;
735 	if ( arcpp == endlist ) {
736 	    prev = &clp -> next;
737 	    clp = clp -> next;
738 	    continue;
739 	}
740 	for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ )
741 	    (*arcpp) -> arc_cyclecnt--;
742 	cyclecnt--;
743 	*prev = clp -> next;
744 	clp = clp -> next;
745 	free( clp );
746     }
747 }
748 
749 #ifdef DEBUG
750 printsubcycle( clp )
751     cltype	*clp;
752 {
753     arctype	**arcpp;
754     arctype	**endlist;
755 
756     arcpp = clp -> list;
757     printf( "%s <cycle %d>\n" , (*arcpp) -> arc_parentp -> name ,
758 	(*arcpp) -> arc_parentp -> cycleno ) ;
759     for ( endlist = &clp -> list[ clp -> size ]; arcpp < endlist ; arcpp++ )
760 	printf( "\t(%ld) -> %s\n" , (*arcpp) -> arc_count ,
761 	    (*arcpp) -> arc_childp -> name ) ;
762 }
763 #endif DEBUG
764 
765 cycletime()
766 {
767     int			cycle;
768     nltype		*cyclenlp;
769     nltype		*childp;
770 
771     for ( cycle = 1 ; cycle <= ncycle ; cycle += 1 ) {
772 	cyclenlp = &cyclenl[ cycle ];
773 	for ( childp = cyclenlp -> cnext ; childp ; childp = childp -> cnext ) {
774 	    if ( childp -> propfraction == 0.0 ) {
775 		    /*
776 		     * all members have the same propfraction except those
777 		     *	that were excluded with -E
778 		     */
779 		continue;
780 	    }
781 	    cyclenlp -> time += childp -> time;
782 	}
783 	cyclenlp -> propself = cyclenlp -> propfraction * cyclenlp -> time;
784     }
785 }
786 
787     /*
788      *	in one top to bottom pass over the topologically sorted namelist
789      *	propagate:
790      *		printflag as the union of parents' printflags
791      *		propfraction as the sum of fractional parents' propfractions
792      *	and while we're here, sum time for functions.
793      */
794 doflags()
795 {
796     int		index;
797     nltype	*childp;
798     nltype	*oldhead;
799 
800     oldhead = 0;
801     for ( index = nname-1 ; index >= 0 ; index -= 1 ) {
802 	childp = topsortnlp[ index ];
803 	    /*
804 	     *	if we haven't done this function or cycle,
805 	     *	inherit things from parent.
806 	     *	this way, we are linear in the number of arcs
807 	     *	since we do all members of a cycle (and the cycle itself)
808 	     *	as we hit the first member of the cycle.
809 	     */
810 	if ( childp -> cyclehead != oldhead ) {
811 	    oldhead = childp -> cyclehead;
812 	    inheritflags( childp );
813 	}
814 #	ifdef DEBUG
815 	    if ( debug & PROPDEBUG ) {
816 		printf( "[doflags] " );
817 		printname( childp );
818 		printf( " inherits printflag %d and propfraction %f\n" ,
819 			childp -> printflag , childp -> propfraction );
820 	    }
821 #	endif DEBUG
822 	if ( ! childp -> printflag ) {
823 		/*
824 		 *	printflag is off
825 		 *	it gets turned on by
826 		 *	being on -f list,
827 		 *	or there not being any -f list and not being on -e list.
828 		 */
829 	    if (   onlist( flist , childp -> name )
830 		|| ( !fflag && !onlist( elist , childp -> name ) ) ) {
831 		childp -> printflag = TRUE;
832 	    }
833 	} else {
834 		/*
835 		 *	this function has printing parents:
836 		 *	maybe someone wants to shut it up
837 		 *	by putting it on -e list.  (but favor -f over -e)
838 		 */
839 	    if (  ( !onlist( flist , childp -> name ) )
840 		&& onlist( elist , childp -> name ) ) {
841 		childp -> printflag = FALSE;
842 	    }
843 	}
844 	if ( childp -> propfraction == 0.0 ) {
845 		/*
846 		 *	no parents to pass time to.
847 		 *	collect time from children if
848 		 *	its on -F list,
849 		 *	or there isn't any -F list and its not on -E list.
850 		 */
851 	    if ( onlist( Flist , childp -> name )
852 		|| ( !Fflag && !onlist( Elist , childp -> name ) ) ) {
853 		    childp -> propfraction = 1.0;
854 	    }
855 	} else {
856 		/*
857 		 *	it has parents to pass time to,
858 		 *	but maybe someone wants to shut it up
859 		 *	by puttting it on -E list.  (but favor -F over -E)
860 		 */
861 	    if (  !onlist( Flist , childp -> name )
862 		&& onlist( Elist , childp -> name ) ) {
863 		childp -> propfraction = 0.0;
864 	    }
865 	}
866 	childp -> propself = childp -> time * childp -> propfraction;
867 	printtime += childp -> propself;
868 #	ifdef DEBUG
869 	    if ( debug & PROPDEBUG ) {
870 		printf( "[doflags] " );
871 		printname( childp );
872 		printf( " ends up with printflag %d and propfraction %f\n" ,
873 			childp -> printflag , childp -> propfraction );
874 		printf( "time %f propself %f printtime %f\n" ,
875 			childp -> time , childp -> propself , printtime );
876 	    }
877 #	endif DEBUG
878     }
879 }
880 
881     /*
882      *	check if any parent of this child
883      *	(or outside parents of this cycle)
884      *	have their print flags on and set the
885      *	print flag of the child (cycle) appropriately.
886      *	similarly, deal with propagation fractions from parents.
887      */
888 inheritflags( childp )
889     nltype	*childp;
890 {
891     nltype	*headp;
892     arctype	*arcp;
893     nltype	*parentp;
894     nltype	*memp;
895 
896     headp = childp -> cyclehead;
897     if ( childp == headp ) {
898 	    /*
899 	     *	just a regular child, check its parents
900 	     */
901 	childp -> printflag = FALSE;
902 	childp -> propfraction = 0.0;
903 	for (arcp = childp -> parents ; arcp ; arcp = arcp -> arc_parentlist) {
904 	    parentp = arcp -> arc_parentp;
905 	    if ( childp == parentp ) {
906 		continue;
907 	    }
908 	    childp -> printflag |= parentp -> printflag;
909 		/*
910 		 *	if the child was never actually called
911 		 *	(e.g. this arc is static (and all others are, too))
912 		 *	no time propagates along this arc.
913 		 */
914 	    if ( arcp -> arc_flags & DEADARC ) {
915 		continue;
916 	    }
917 	    if ( childp -> npropcall ) {
918 		childp -> propfraction += parentp -> propfraction
919 					* ( ( (double) arcp -> arc_count )
920 					  / ( (double) childp -> npropcall ) );
921 	    }
922 	}
923     } else {
924 	    /*
925 	     *	its a member of a cycle, look at all parents from
926 	     *	outside the cycle
927 	     */
928 	headp -> printflag = FALSE;
929 	headp -> propfraction = 0.0;
930 	for ( memp = headp -> cnext ; memp ; memp = memp -> cnext ) {
931 	    for (arcp = memp->parents ; arcp ; arcp = arcp->arc_parentlist) {
932 		if ( arcp -> arc_parentp -> cyclehead == headp ) {
933 		    continue;
934 		}
935 		parentp = arcp -> arc_parentp;
936 		headp -> printflag |= parentp -> printflag;
937 		    /*
938 		     *	if the cycle was never actually called
939 		     *	(e.g. this arc is static (and all others are, too))
940 		     *	no time propagates along this arc.
941 		     */
942 		if ( arcp -> arc_flags & DEADARC ) {
943 		    continue;
944 		}
945 		if ( headp -> npropcall ) {
946 		    headp -> propfraction += parentp -> propfraction
947 					* ( ( (double) arcp -> arc_count )
948 					  / ( (double) headp -> npropcall ) );
949 		}
950 	    }
951 	}
952 	for ( memp = headp ; memp ; memp = memp -> cnext ) {
953 	    memp -> printflag = headp -> printflag;
954 	    memp -> propfraction = headp -> propfraction;
955 	}
956     }
957 }
958