xref: /openbsd-src/usr.bin/gprof/arcs.c (revision a28daedfc357b214be5c701aa8ba8adb29a7f1c2)
1 /*	$OpenBSD: arcs.c,v 1.11 2007/11/26 09:28:34 martynas Exp $	*/
2 /*	$NetBSD: arcs.c,v 1.6 1995/04/19 07:15:52 cgd Exp $	*/
3 
4 /*
5  * Copyright (c) 1983, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #ifndef lint
34 #if 0
35 static char sccsid[] = "@(#)arcs.c	8.1 (Berkeley) 6/6/93";
36 #else
37 static char rcsid[] = "$OpenBSD: arcs.c,v 1.11 2007/11/26 09:28:34 martynas Exp $";
38 #endif
39 #endif /* not lint */
40 
41 #include "gprof.h"
42 
43 #ifdef DEBUG
44 int visited;
45 int viable;
46 int newcycle;
47 int oldcycle;
48 void printsubcycle(cltype *);
49 #endif /* DEBUG */
50 
51     /*
52      *	add (or just increment) an arc
53      */
54 void
55 addarc(nltype *parentp, nltype *childp, long count)
56 {
57     arctype		*arcp;
58 
59 #   ifdef DEBUG
60 	if ( debug & TALLYDEBUG ) {
61 	    printf( "[addarc] %ld arcs from %s to %s\n" ,
62 		    count , parentp -> name , childp -> name );
63 	}
64 #   endif /* DEBUG */
65     arcp = arclookup( parentp , childp );
66     if ( arcp != 0 ) {
67 	    /*
68 	     *	a hit:  just increment the count.
69 	     */
70 #	ifdef DEBUG
71 	    if ( debug & TALLYDEBUG ) {
72 		printf( "[tally] hit %ld += %ld\n" ,
73 			arcp -> arc_count , count );
74 	    }
75 #	endif /* DEBUG */
76 	arcp -> arc_count += count;
77 	return;
78     }
79     arcp = (arctype *)calloc( 1 , sizeof *arcp );
80     arcp -> arc_parentp = parentp;
81     arcp -> arc_childp = childp;
82     arcp -> arc_count = count;
83 	/*
84 	 *	prepend this child to the children of this parent
85 	 */
86     arcp -> arc_childlist = parentp -> children;
87     parentp -> children = arcp;
88 	/*
89 	 *	prepend this parent to the parents of this child
90 	 */
91     arcp -> arc_parentlist = childp -> parents;
92     childp -> parents = arcp;
93 }
94 
95     /*
96      *	the code below topologically sorts the graph (collapsing cycles),
97      *	and propagates time bottom up and flags top down.
98      */
99 
100     /*
101      *	the topologically sorted name list pointers
102      */
103 nltype	**topsortnlp;
104 
105 int
106 topcmp(nltype **npp1, nltype **npp2)
107 {
108     return (*npp1) -> toporder - (*npp2) -> toporder;
109 }
110 
111 nltype **
112 doarcs()
113 {
114     nltype	*parentp, **timesortnlp;
115     arctype	*arcp;
116     long	index;
117     long	pass;
118 
119 	/*
120 	 *	initialize various things:
121 	 *	    zero out child times.
122 	 *	    count self-recursive calls.
123 	 *	    indicate that nothing is on cycles.
124 	 */
125     for ( parentp = nl ; parentp < npe ; parentp++ ) {
126 	parentp -> childtime = 0.0;
127 	arcp = arclookup( parentp , parentp );
128 	if ( arcp != 0 ) {
129 	    parentp -> ncall -= arcp -> arc_count;
130 	    parentp -> selfcalls = arcp -> arc_count;
131 	} else {
132 	    parentp -> selfcalls = 0;
133 	}
134 	parentp -> npropcall = parentp -> ncall;
135 	parentp -> propfraction = 0.0;
136 	parentp -> propself = 0.0;
137 	parentp -> propchild = 0.0;
138 	parentp -> printflag = FALSE;
139 	parentp -> toporder = DFN_NAN;
140 	parentp -> cycleno = 0;
141 	parentp -> cyclehead = parentp;
142 	parentp -> cnext = 0;
143 	if ( cflag ) {
144 	    findcall( parentp , parentp -> value , (parentp+1) -> value );
145 	}
146     }
147     for ( pass = 1 ; ; pass++ ) {
148 	    /*
149 	     *	topologically order things
150 	     *	if any node is unnumbered,
151 	     *	    number it and any of its descendents.
152 	     */
153 	for ( dfn_init() , parentp = nl ; parentp < npe ; parentp++ ) {
154 	    if ( parentp -> toporder == DFN_NAN ) {
155 		dfn( parentp );
156 	    }
157 	}
158 	    /*
159 	     *	link together nodes on the same cycle
160 	     */
161 	cyclelink();
162 	    /*
163 	     *	if no cycles to break up, proceed
164 	     */
165 	if ( ! Cflag )
166 	    break;
167 	    /*
168 	     *	analyze cycles to determine breakup
169 	     */
170 #	ifdef DEBUG
171 	    if ( debug & BREAKCYCLE ) {
172 		printf("[doarcs] pass %ld, cycle(s) %d\n" , pass , ncycle );
173 	    }
174 #	endif /* DEBUG */
175 	if ( pass == 1 ) {
176 	    printf( "\n\n%s %s\n%s %d:\n" ,
177 		"The following arcs were deleted" ,
178 		"from the propagation calculation" ,
179 		"to reduce the maximum cycle size to", cyclethreshold );
180 	}
181 	if ( cycleanalyze() )
182 	    break;
183 	free ( cyclenl );
184 	ncycle = 0;
185 	for ( parentp = nl ; parentp < npe ; parentp++ ) {
186 	    parentp -> toporder = DFN_NAN;
187 	    parentp -> cycleno = 0;
188 	    parentp -> cyclehead = parentp;
189 	    parentp -> cnext = 0;
190 	}
191     }
192     if ( pass > 1 ) {
193 	printf( "\f\n" );
194     } else {
195 	printf( "\tNone\n\n" );
196     }
197 	/*
198 	 *	Sort the symbol table in reverse topological order
199 	 */
200     topsortnlp = (nltype **) calloc( nname , sizeof(nltype *) );
201     if ( topsortnlp == (nltype **) 0 )
202 	warnx("[doarcs] ran out of memory for topo sorting");
203     for ( index = 0 ; index < nname ; index += 1 ) {
204 	topsortnlp[ index ] = &nl[ index ];
205     }
206     qsort( topsortnlp , nname , sizeof(nltype *) , topcmp );
207 #   ifdef DEBUG
208 	if ( debug & DFNDEBUG ) {
209 	    printf( "[doarcs] topological sort listing\n" );
210 	    for ( index = 0 ; index < nname ; index += 1 ) {
211 		printf( "[doarcs] " );
212 		printf( "%d:" , topsortnlp[ index ] -> toporder );
213 		printname( topsortnlp[ index ] );
214 		printf( "\n" );
215 	    }
216 	}
217 #   endif /* DEBUG */
218 	/*
219 	 *	starting from the topological top,
220 	 *	propagate print flags to children.
221 	 *	also, calculate propagation fractions.
222 	 *	this happens before time propagation
223 	 *	since time propagation uses the fractions.
224 	 */
225     doflags();
226 	/*
227 	 *	starting from the topological bottom,
228 	 *	propagate children times up to parents.
229 	 */
230     dotime();
231 	/*
232 	 *	Now, sort by propself + propchild.
233 	 *	sorting both the regular function names
234 	 *	and cycle headers.
235 	 */
236     timesortnlp = (nltype **) calloc( nname + ncycle , sizeof(nltype *) );
237     if ( timesortnlp == (nltype **) 0 )
238 	warnx("ran out of memory for sorting");
239     for ( index = 0 ; index < nname ; index++ ) {
240 	timesortnlp[index] = &nl[index];
241     }
242     for ( index = 1 ; index <= ncycle ; index++ ) {
243 	timesortnlp[nname+index-1] = &cyclenl[index];
244     }
245     qsort( timesortnlp , nname + ncycle , sizeof(nltype *) , totalcmp );
246     for ( index = 0 ; index < nname + ncycle ; index++ ) {
247 	timesortnlp[ index ] -> index = index + 1;
248     }
249     return( timesortnlp );
250 }
251 
252 void
253 dotime()
254 {
255     int	index;
256 
257     cycletime();
258     for ( index = 0 ; index < nname ; index += 1 ) {
259 	timepropagate( topsortnlp[ index ] );
260     }
261 }
262 
263 void
264 timepropagate(nltype *parentp)
265 {
266     arctype	*arcp;
267     nltype	*childp;
268     double	share;
269     double	propshare;
270 
271     if ( parentp -> propfraction == 0.0 ) {
272 	return;
273     }
274 	/*
275 	 *	gather time from children of this parent.
276 	 */
277     for ( arcp = parentp -> children ; arcp ; arcp = arcp -> arc_childlist ) {
278 	childp = arcp -> arc_childp;
279 	if ( arcp -> arc_flags & DEADARC ) {
280 	    continue;
281 	}
282 	if ( arcp -> arc_count == 0 ) {
283 	    continue;
284 	}
285 	if ( childp == parentp ) {
286 	    continue;
287 	}
288 	if ( childp -> propfraction == 0.0 ) {
289 	    continue;
290 	}
291 	if ( childp -> cyclehead != childp ) {
292 	    if ( parentp -> cycleno == childp -> cycleno ) {
293 		continue;
294 	    }
295 	    if ( parentp -> toporder <= childp -> toporder )
296 		warnx("[propagate] toporder botches");
297 	    childp = childp -> cyclehead;
298 	} else {
299 	    if ( parentp -> toporder <= childp -> toporder ) {
300 		warnx("[propagate] toporder botches");
301 		continue;
302 	    }
303 	}
304 	if ( childp -> npropcall == 0 ) {
305 	    continue;
306 	}
307 	    /*
308 	     *	distribute time for this arc
309 	     */
310 	arcp -> arc_time = childp -> time
311 			        * ( ( (double) arcp -> arc_count ) /
312 				    ( (double) childp -> npropcall ) );
313 	arcp -> arc_childtime = childp -> childtime
314 			        * ( ( (double) arcp -> arc_count ) /
315 				    ( (double) childp -> npropcall ) );
316 	share = arcp -> arc_time + arcp -> arc_childtime;
317 	parentp -> childtime += share;
318 	    /*
319 	     *	( 1 - propfraction ) gets lost along the way
320 	     */
321 	propshare = parentp -> propfraction * share;
322 	    /*
323 	     *	fix things for printing
324 	     */
325 	parentp -> propchild += propshare;
326 	arcp -> arc_time *= parentp -> propfraction;
327 	arcp -> arc_childtime *= parentp -> propfraction;
328 	    /*
329 	     *	add this share to the parent's cycle header, if any.
330 	     */
331 	if ( parentp -> cyclehead != parentp ) {
332 	    parentp -> cyclehead -> childtime += share;
333 	    parentp -> cyclehead -> propchild += propshare;
334 	}
335 #	ifdef DEBUG
336 	    if ( debug & PROPDEBUG ) {
337 		printf( "[dotime] child \t" );
338 		printname( childp );
339 		printf( " with %f %f %ld/%ld\n" ,
340 			childp -> time , childp -> childtime ,
341 			arcp -> arc_count , childp -> npropcall );
342 		printf( "[dotime] parent\t" );
343 		printname( parentp );
344 		printf( "\n[dotime] share %f\n" , share );
345 	    }
346 #	endif /* DEBUG */
347     }
348 }
349 
350 void
351 cyclelink()
352 {
353     nltype	*nlp;
354     nltype	*cyclenlp;
355     int			cycle;
356     nltype		*memberp;
357     arctype		*arcp;
358 
359 	/*
360 	 *	Count the number of cycles, and initialze the cycle lists
361 	 */
362     ncycle = 0;
363     for ( nlp = nl ; nlp < npe ; nlp++ ) {
364 	    /*
365 	     *	this is how you find unattached cycles
366 	     */
367 	if ( nlp -> cyclehead == nlp && nlp -> cnext != 0 ) {
368 	    ncycle += 1;
369 	}
370     }
371 	/*
372 	 *	cyclenl is indexed by cycle number:
373 	 *	i.e. it is origin 1, not origin 0.
374 	 */
375     cyclenl = (nltype *) calloc( ncycle + 1 , sizeof( nltype ) );
376     if ( cyclenl == 0 )
377 	errx(0, "No room for %ld bytes of cycle headers",
378 	    (ncycle + 1) * sizeof(nltype));
379 	/*
380 	 *	now link cycles to true cycleheads,
381 	 *	number them, accumulate the data for the cycle
382 	 */
383     cycle = 0;
384     for ( nlp = nl ; nlp < npe ; nlp++ ) {
385 	if ( !( nlp -> cyclehead == nlp && nlp -> cnext != 0 ) ) {
386 	    continue;
387 	}
388 	cycle += 1;
389 	cyclenlp = &cyclenl[cycle];
390         cyclenlp -> name = 0;		/* the name */
391         cyclenlp -> value = 0;		/* the pc entry point */
392         cyclenlp -> time = 0.0;		/* ticks in this routine */
393         cyclenlp -> childtime = 0.0;	/* cumulative ticks in children */
394 	cyclenlp -> ncall = 0;		/* how many times called */
395 	cyclenlp -> selfcalls = 0;	/* how many calls to self */
396 	cyclenlp -> propfraction = 0.0;	/* what % of time propagates */
397 	cyclenlp -> propself = 0.0;	/* how much self time propagates */
398 	cyclenlp -> propchild = 0.0;	/* how much child time propagates */
399 	cyclenlp -> printflag = TRUE;	/* should this be printed? */
400 	cyclenlp -> index = 0;		/* index in the graph list */
401 	cyclenlp -> toporder = DFN_NAN;	/* graph call chain top-sort order */
402 	cyclenlp -> cycleno = cycle;	/* internal number of cycle on */
403 	cyclenlp -> cyclehead = cyclenlp;	/* pointer to head of cycle */
404 	cyclenlp -> cnext = nlp;	/* pointer to next member of cycle */
405 	cyclenlp -> parents = 0;	/* list of caller arcs */
406 	cyclenlp -> children = 0;	/* list of callee arcs */
407 #	ifdef DEBUG
408 	    if ( debug & CYCLEDEBUG ) {
409 		printf( "[cyclelink] " );
410 		printname( nlp );
411 		printf( " is the head of cycle %d\n" , cycle );
412 	    }
413 #	endif /* DEBUG */
414 	    /*
415 	     *	link members to cycle header
416 	     */
417 	for ( memberp = nlp ; memberp ; memberp = memberp -> cnext ) {
418 	    memberp -> cycleno = cycle;
419 	    memberp -> cyclehead = cyclenlp;
420 	}
421 	    /*
422 	     *	count calls from outside the cycle
423 	     *	and those among cycle members
424 	     */
425 	for ( memberp = nlp ; memberp ; memberp = memberp -> cnext ) {
426 	    for ( arcp=memberp->parents ; arcp ; arcp=arcp->arc_parentlist ) {
427 		if ( arcp -> arc_parentp == memberp ) {
428 		    continue;
429 		}
430 		if ( arcp -> arc_parentp -> cycleno == cycle ) {
431 		    cyclenlp -> selfcalls += arcp -> arc_count;
432 		} else {
433 		    cyclenlp -> npropcall += arcp -> arc_count;
434 		}
435 	    }
436 	}
437     }
438 }
439 
440     /*
441      *	analyze cycles to determine breakup
442      */
443 int
444 cycleanalyze()
445 {
446     arctype	**cyclestack;
447     arctype	**stkp;
448     arctype	**arcpp;
449     arctype	**endlist;
450     arctype	*arcp;
451     nltype	*nlp;
452     cltype	*clp;
453     bool	ret;
454     bool	done;
455     int		size;
456     int		cycleno;
457 
458 	/*
459 	 *	calculate the size of the cycle, and find nodes that
460 	 *	exit the cycle as they are desirable targets to cut
461 	 *	some of their parents
462 	 */
463     for ( done = TRUE , cycleno = 1 ; cycleno <= ncycle ; cycleno++ ) {
464 	size = 0;
465 	for (nlp = cyclenl[ cycleno ] . cnext; nlp; nlp = nlp -> cnext) {
466 	    size += 1;
467 	    nlp -> parentcnt = 0;
468 	    nlp -> flags &= ~HASCYCLEXIT;
469 	    for ( arcp = nlp -> parents; arcp; arcp = arcp -> arc_parentlist ) {
470 		nlp -> parentcnt += 1;
471 		if ( arcp -> arc_parentp -> cycleno != cycleno )
472 		    nlp -> flags |= HASCYCLEXIT;
473 	    }
474 	}
475 	if ( size <= cyclethreshold )
476 	    continue;
477 	done = FALSE;
478         cyclestack = (arctype **) calloc( size + 1 , sizeof( arctype *) );
479 	if ( cyclestack == 0 ) {
480 	    warnx("No room for %ld bytes of cycle stack" ,
481 		(size + 1) * sizeof(arctype *));
482 	    return (done);
483 	}
484 #	ifdef DEBUG
485 	    if ( debug & BREAKCYCLE ) {
486 		printf( "[cycleanalyze] starting cycle %d of %d, size %d\n" ,
487 		    cycleno , ncycle , size );
488 	    }
489 #	endif /* DEBUG */
490 	for ( nlp = cyclenl[ cycleno ] . cnext ; nlp ; nlp = nlp -> cnext ) {
491 	    stkp = &cyclestack[0];
492 	    nlp -> flags |= CYCLEHEAD;
493 	    ret = descend ( nlp , cyclestack , stkp );
494 	    nlp -> flags &= ~CYCLEHEAD;
495 	    if ( ret == FALSE )
496 		break;
497 	}
498 	free( cyclestack );
499 	if ( cyclecnt > 0 ) {
500 	    compresslist();
501 	    for ( clp = cyclehead ; clp ; ) {
502 		endlist = &clp -> list[ clp -> size ];
503 		for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ )
504 		    (*arcpp) -> arc_cyclecnt--;
505 		cyclecnt--;
506 		clp = clp -> next;
507 		free( clp );
508 	    }
509 	    cyclehead = 0;
510 	}
511     }
512 #   ifdef DEBUG
513 	if ( debug & BREAKCYCLE ) {
514 	    printf("%s visited %d, viable %d, newcycle %d, oldcycle %d\n",
515 		"[doarcs]" , visited , viable , newcycle , oldcycle);
516 	}
517 #   endif /* DEBUG */
518     return (done);
519 }
520 
521 int
522 descend(nltype *node, arctype **stkstart, arctype **stkp)
523 {
524     arctype	*arcp;
525     bool	ret;
526 
527     for ( arcp = node -> children ; arcp ; arcp = arcp -> arc_childlist ) {
528 #	ifdef DEBUG
529 	    visited++;
530 #	endif /* DEBUG */
531 	if ( arcp -> arc_childp -> cycleno != node -> cycleno
532 	    || ( arcp -> arc_childp -> flags & VISITED )
533 	    || ( arcp -> arc_flags & DEADARC ) )
534 	    continue;
535 #	ifdef DEBUG
536 	    viable++;
537 #	endif /* DEBUG */
538 	*stkp = arcp;
539 	if ( arcp -> arc_childp -> flags & CYCLEHEAD ) {
540 	    if ( addcycle( stkstart , stkp ) == FALSE )
541 		return( FALSE );
542 	    continue;
543 	}
544 	arcp -> arc_childp -> flags |= VISITED;
545 	ret = descend( arcp -> arc_childp , stkstart , stkp + 1 );
546 	arcp -> arc_childp -> flags &= ~VISITED;
547 	if ( ret == FALSE )
548 	    return( FALSE );
549     }
550     return (TRUE);
551 }
552 
553 int
554 addcycle(arctype **stkstart, arctype **stkend)
555 {
556     arctype	**arcpp;
557     arctype	**stkloc;
558     arctype	**stkp;
559     arctype	**endlist;
560     arctype	*minarc;
561     arctype	*arcp;
562     cltype	*clp;
563     int		size;
564 
565     size = stkend - stkstart + 1;
566     if ( size <= 1 )
567 	return( TRUE );
568     for ( arcpp = stkstart , minarc = *arcpp ; arcpp <= stkend ; arcpp++ ) {
569 	if ( *arcpp > minarc )
570 	    continue;
571 	minarc = *arcpp;
572 	stkloc = arcpp;
573     }
574     for ( clp = cyclehead ; clp ; clp = clp -> next ) {
575 	if ( clp -> size != size )
576 	    continue;
577 	stkp = stkloc;
578 	endlist = &clp -> list[ size ];
579 	for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ ) {
580 	    if ( *stkp++ != *arcpp )
581 		break;
582 	    if ( stkp > stkend )
583 		stkp = stkstart;
584 	}
585 	if ( arcpp == endlist ) {
586 #	    ifdef DEBUG
587 		oldcycle++;
588 #	    endif /* DEBUG */
589 	    return( TRUE );
590 	}
591     }
592     clp = (cltype *)
593 	calloc( 1 , sizeof ( cltype ) + ( size - 1 ) * sizeof( arctype * ) );
594     if ( clp == 0 ) {
595 	warnx("No room for %ld bytes of subcycle storage" ,
596 	    sizeof(cltype) + (size - 1) * sizeof(arctype *));
597 	return( FALSE );
598     }
599     stkp = stkloc;
600     endlist = &clp -> list[ size ];
601     for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ ) {
602 	arcp = *arcpp = *stkp++;
603 	if ( stkp > stkend )
604 	    stkp = stkstart;
605 	arcp -> arc_cyclecnt++;
606 	if ( ( arcp -> arc_flags & ONLIST ) == 0 ) {
607 	    arcp -> arc_flags |= ONLIST;
608 	    arcp -> arc_next = archead;
609 	    archead = arcp;
610 	}
611     }
612     clp -> size = size;
613     clp -> next = cyclehead;
614     cyclehead = clp;
615 #   ifdef DEBUG
616 	newcycle++;
617 	if ( debug & SUBCYCLELIST ) {
618 	    printsubcycle( clp );
619 	}
620 #   endif /* DEBUG */
621     cyclecnt++;
622     if ( cyclecnt >= CYCLEMAX )
623 	return( FALSE );
624     return( TRUE );
625 }
626 
627 void
628 compresslist()
629 {
630     cltype	*clp;
631     cltype	**prev;
632     arctype	**arcpp;
633     arctype	**endlist;
634     arctype	*arcp;
635     arctype	*maxarcp;
636     arctype	*maxexitarcp;
637     arctype	*maxwithparentarcp;
638     arctype	*maxnoparentarcp;
639     int		maxexitcnt;
640     int		maxwithparentcnt;
641     int		maxnoparentcnt;
642 #   ifdef DEBUG
643         char	*type;
644 #   endif
645 
646     maxexitcnt = 0;
647     maxwithparentcnt = 0;
648     maxnoparentcnt = 0;
649     for ( endlist = &archead , arcp = archead ; arcp ; ) {
650 	if ( arcp -> arc_cyclecnt == 0 ) {
651 	    arcp -> arc_flags &= ~ONLIST;
652 	    *endlist = arcp -> arc_next;
653 	    arcp -> arc_next = 0;
654 	    arcp = *endlist;
655 	    continue;
656 	}
657 	if ( arcp -> arc_childp -> flags & HASCYCLEXIT ) {
658 	    if ( arcp -> arc_cyclecnt > maxexitcnt ||
659 		( arcp -> arc_cyclecnt == maxexitcnt &&
660 		arcp -> arc_cyclecnt < maxexitarcp -> arc_count ) ) {
661 		maxexitcnt = arcp -> arc_cyclecnt;
662 		maxexitarcp = arcp;
663 	    }
664 	} else if ( arcp -> arc_childp -> parentcnt > 1 ) {
665 	    if ( arcp -> arc_cyclecnt > maxwithparentcnt ||
666 		( arcp -> arc_cyclecnt == maxwithparentcnt &&
667 		arcp -> arc_cyclecnt < maxwithparentarcp -> arc_count ) ) {
668 		maxwithparentcnt = arcp -> arc_cyclecnt;
669 		maxwithparentarcp = arcp;
670 	    }
671 	} else {
672 	    if ( arcp -> arc_cyclecnt > maxnoparentcnt ||
673 		( arcp -> arc_cyclecnt == maxnoparentcnt &&
674 		arcp -> arc_cyclecnt < maxnoparentarcp -> arc_count ) ) {
675 		maxnoparentcnt = arcp -> arc_cyclecnt;
676 		maxnoparentarcp = arcp;
677 	    }
678 	}
679 	endlist = &arcp -> arc_next;
680 	arcp = arcp -> arc_next;
681     }
682     if ( maxexitcnt > 0 ) {
683 	/*
684 	 *	first choice is edge leading to node with out-of-cycle parent
685 	 */
686 	maxarcp = maxexitarcp;
687 #	ifdef DEBUG
688 	    type = "exit";
689 #	endif /* DEBUG */
690     } else if ( maxwithparentcnt > 0 ) {
691 	/*
692 	 *	second choice is edge leading to node with at least one
693 	 *	other in-cycle parent
694 	 */
695 	maxarcp = maxwithparentarcp;
696 #	ifdef DEBUG
697 	    type = "internal";
698 #	endif /* DEBUG */
699     } else {
700 	/*
701 	 *	last choice is edge leading to node with only this arc as
702 	 *	a parent (as it will now be orphaned)
703 	 */
704 	maxarcp = maxnoparentarcp;
705 #	ifdef DEBUG
706 	    type = "orphan";
707 #	endif /* DEBUG */
708     }
709     maxarcp -> arc_flags |= DEADARC;
710     maxarcp -> arc_childp -> parentcnt -= 1;
711     maxarcp -> arc_childp -> npropcall -= maxarcp -> arc_count;
712 #   ifdef DEBUG
713 	if ( debug & BREAKCYCLE ) {
714 	    printf("[compresslist] delete %s arc: "
715 		"%s (%ld) -> %s from %d cycle(s)\n", type,
716 		maxarcp -> arc_parentp -> name, maxarcp -> arc_count,
717 		maxarcp -> arc_childp -> name, maxarcp -> arc_cyclecnt);
718 	}
719 #   endif /* DEBUG */
720     printf("\t%s to %s with %ld calls\n", maxarcp->arc_parentp -> name,
721 	maxarcp->arc_childp->name, maxarcp->arc_count);
722     prev = &cyclehead;
723     for ( clp = cyclehead ; clp ; ) {
724 	endlist = &clp -> list[ clp -> size ];
725 	for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ )
726 	    if ( (*arcpp) -> arc_flags & DEADARC )
727 		break;
728 	if ( arcpp == endlist ) {
729 	    prev = &clp -> next;
730 	    clp = clp -> next;
731 	    continue;
732 	}
733 	for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ )
734 	    (*arcpp) -> arc_cyclecnt--;
735 	cyclecnt--;
736 	*prev = clp -> next;
737 	free( clp );
738 	clp = *prev;
739     }
740 }
741 
742 #ifdef DEBUG
743 void
744 printsubcycle(cltype *clp)
745 {
746     arctype	**arcpp;
747     arctype	**endlist;
748 
749     arcpp = clp -> list;
750     printf( "%s <cycle %d>\n" , (*arcpp) -> arc_parentp -> name ,
751 	(*arcpp) -> arc_parentp -> cycleno ) ;
752     for ( endlist = &clp -> list[ clp -> size ]; arcpp < endlist ; arcpp++ )
753 	printf( "\t(%ld) -> %s\n" , (*arcpp) -> arc_count ,
754 	    (*arcpp) -> arc_childp -> name ) ;
755 }
756 #endif /* DEBUG */
757 
758 void
759 cycletime()
760 {
761     int			cycle;
762     nltype		*cyclenlp;
763     nltype		*childp;
764 
765     for ( cycle = 1 ; cycle <= ncycle ; cycle += 1 ) {
766 	cyclenlp = &cyclenl[ cycle ];
767 	for ( childp = cyclenlp -> cnext ; childp ; childp = childp -> cnext ) {
768 	    if ( childp -> propfraction == 0.0 ) {
769 		    /*
770 		     * all members have the same propfraction except those
771 		     *	that were excluded with -E
772 		     */
773 		continue;
774 	    }
775 	    cyclenlp -> time += childp -> time;
776 	}
777 	cyclenlp -> propself = cyclenlp -> propfraction * cyclenlp -> time;
778     }
779 }
780 
781     /*
782      *	in one top to bottom pass over the topologically sorted namelist
783      *	propagate:
784      *		printflag as the union of parents' printflags
785      *		propfraction as the sum of fractional parents' propfractions
786      *	and while we're here, sum time for functions.
787      */
788 void
789 doflags()
790 {
791     int		index;
792     nltype	*childp;
793     nltype	*oldhead;
794 
795     oldhead = 0;
796     for ( index = nname-1 ; index >= 0 ; index -= 1 ) {
797 	childp = topsortnlp[ index ];
798 	    /*
799 	     *	if we haven't done this function or cycle,
800 	     *	inherit things from parent.
801 	     *	this way, we are linear in the number of arcs
802 	     *	since we do all members of a cycle (and the cycle itself)
803 	     *	as we hit the first member of the cycle.
804 	     */
805 	if ( childp -> cyclehead != oldhead ) {
806 	    oldhead = childp -> cyclehead;
807 	    inheritflags( childp );
808 	}
809 #	ifdef DEBUG
810 	    if ( debug & PROPDEBUG ) {
811 		printf( "[doflags] " );
812 		printname( childp );
813 		printf( " inherits printflag %d and propfraction %f\n" ,
814 			childp -> printflag , childp -> propfraction );
815 	    }
816 #	endif /* DEBUG */
817 	if ( ! childp -> printflag ) {
818 		/*
819 		 *	printflag is off
820 		 *	it gets turned on by
821 		 *	being on -f list,
822 		 *	or there not being any -f list and not being on -e list.
823 		 */
824 	    if (   onlist( flist , childp -> name )
825 		|| ( !fflag && !onlist( elist , childp -> name ) ) ) {
826 		childp -> printflag = TRUE;
827 	    }
828 	} else {
829 		/*
830 		 *	this function has printing parents:
831 		 *	maybe someone wants to shut it up
832 		 *	by putting it on -e list.  (but favor -f over -e)
833 		 */
834 	    if (  ( !onlist( flist , childp -> name ) )
835 		&& onlist( elist , childp -> name ) ) {
836 		childp -> printflag = FALSE;
837 	    }
838 	}
839 	if ( childp -> propfraction == 0.0 ) {
840 		/*
841 		 *	no parents to pass time to.
842 		 *	collect time from children if
843 		 *	its on -F list,
844 		 *	or there isn't any -F list and its not on -E list.
845 		 */
846 	    if ( onlist( Flist , childp -> name )
847 		|| ( !Fflag && !onlist( Elist , childp -> name ) ) ) {
848 		    childp -> propfraction = 1.0;
849 	    }
850 	} else {
851 		/*
852 		 *	it has parents to pass time to,
853 		 *	but maybe someone wants to shut it up
854 		 *	by puttting it on -E list.  (but favor -F over -E)
855 		 */
856 	    if (  !onlist( Flist , childp -> name )
857 		&& onlist( Elist , childp -> name ) ) {
858 		childp -> propfraction = 0.0;
859 	    }
860 	}
861 	childp -> propself = childp -> time * childp -> propfraction;
862 	printtime += childp -> propself;
863 #	ifdef DEBUG
864 	    if ( debug & PROPDEBUG ) {
865 		printf( "[doflags] " );
866 		printname( childp );
867 		printf( " ends up with printflag %d and propfraction %f\n" ,
868 			childp -> printflag , childp -> propfraction );
869 		printf( "time %f propself %f printtime %f\n" ,
870 			childp -> time , childp -> propself , printtime );
871 	    }
872 #	endif /* DEBUG */
873     }
874 }
875 
876     /*
877      *	check if any parent of this child
878      *	(or outside parents of this cycle)
879      *	have their print flags on and set the
880      *	print flag of the child (cycle) appropriately.
881      *	similarly, deal with propagation fractions from parents.
882      */
883 void
884 inheritflags(nltype *childp)
885 {
886     nltype	*headp;
887     arctype	*arcp;
888     nltype	*parentp;
889     nltype	*memp;
890 
891     headp = childp -> cyclehead;
892     if ( childp == headp ) {
893 	    /*
894 	     *	just a regular child, check its parents
895 	     */
896 	childp -> printflag = FALSE;
897 	childp -> propfraction = 0.0;
898 	for (arcp = childp -> parents ; arcp ; arcp = arcp -> arc_parentlist) {
899 	    parentp = arcp -> arc_parentp;
900 	    if ( childp == parentp ) {
901 		continue;
902 	    }
903 	    childp -> printflag |= parentp -> printflag;
904 		/*
905 		 *	if the child was never actually called
906 		 *	(e.g. this arc is static (and all others are, too))
907 		 *	no time propagates along this arc.
908 		 */
909 	    if ( arcp -> arc_flags & DEADARC ) {
910 		continue;
911 	    }
912 	    if ( childp -> npropcall ) {
913 		childp -> propfraction += parentp -> propfraction
914 					* ( ( (double) arcp -> arc_count )
915 					  / ( (double) childp -> npropcall ) );
916 	    }
917 	}
918     } else {
919 	    /*
920 	     *	its a member of a cycle, look at all parents from
921 	     *	outside the cycle
922 	     */
923 	headp -> printflag = FALSE;
924 	headp -> propfraction = 0.0;
925 	for ( memp = headp -> cnext ; memp ; memp = memp -> cnext ) {
926 	    for (arcp = memp->parents ; arcp ; arcp = arcp->arc_parentlist) {
927 		if ( arcp -> arc_parentp -> cyclehead == headp ) {
928 		    continue;
929 		}
930 		parentp = arcp -> arc_parentp;
931 		headp -> printflag |= parentp -> printflag;
932 		    /*
933 		     *	if the cycle was never actually called
934 		     *	(e.g. this arc is static (and all others are, too))
935 		     *	no time propagates along this arc.
936 		     */
937 		if ( arcp -> arc_flags & DEADARC ) {
938 		    continue;
939 		}
940 		if ( headp -> npropcall ) {
941 		    headp -> propfraction += parentp -> propfraction
942 					* ( ( (double) arcp -> arc_count )
943 					  / ( (double) headp -> npropcall ) );
944 		}
945 	    }
946 	}
947 	for ( memp = headp ; memp ; memp = memp -> cnext ) {
948 	    memp -> printflag = headp -> printflag;
949 	    memp -> propfraction = headp -> propfraction;
950 	}
951     }
952 }
953