xref: /freebsd/usr.bin/gprof/arcs.c (revision 4f29da19bd44f0e99f021510460a81bf754c21d2)
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 #if 0
35 #ifndef lint
36 static char sccsid[] = "@(#)arcs.c	8.1 (Berkeley) 6/6/93";
37 #endif /* not lint */
38 #endif
39 
40 #include <sys/cdefs.h>
41 __FBSDID("$FreeBSD$");
42 
43 #include <err.h>
44 #include "gprof.h"
45 
46 #ifdef DEBUG
47 int visited;
48 int viable;
49 int newcycle;
50 int oldcycle;
51 #endif /* DEBUG */
52 
53     /*
54      *	add (or just increment) an arc
55      */
56 void
57 addarc( parentp , childp , count )
58     nltype	*parentp;
59     nltype	*childp;
60     long	count;
61 {
62     arctype		*arcp;
63 
64 #   ifdef DEBUG
65 	if ( debug & TALLYDEBUG ) {
66 	    printf( "[addarc] %ld arcs from %s to %s\n" ,
67 		    count , parentp -> name , childp -> name );
68 	}
69 #   endif /* DEBUG */
70     arcp = arclookup( parentp , childp );
71     if ( arcp != 0 ) {
72 	    /*
73 	     *	a hit:  just increment the count.
74 	     */
75 #	ifdef DEBUG
76 	    if ( debug & TALLYDEBUG ) {
77 		printf( "[tally] hit %ld += %ld\n" ,
78 			arcp -> arc_count , count );
79 	    }
80 #	endif /* DEBUG */
81 	arcp -> arc_count += count;
82 	return;
83     }
84     arcp = (arctype *)calloc( 1 , sizeof *arcp );
85     if (arcp == NULL)
86 	errx( 1 , "malloc failed" );
87     arcp -> arc_parentp = parentp;
88     arcp -> arc_childp = childp;
89     arcp -> arc_count = count;
90 	/*
91 	 *	prepend this child to the children of this parent
92 	 */
93     arcp -> arc_childlist = parentp -> children;
94     parentp -> children = arcp;
95 	/*
96 	 *	prepend this parent to the parents of this child
97 	 */
98     arcp -> arc_parentlist = childp -> parents;
99     childp -> parents = arcp;
100 }
101 
102     /*
103      *	the code below topologically sorts the graph (collapsing cycles),
104      *	and propagates time bottom up and flags top down.
105      */
106 
107     /*
108      *	the topologically sorted name list pointers
109      */
110 nltype	**topsortnlp;
111 
112 int
113 topcmp( npp1 , npp2 )
114     nltype	**npp1;
115     nltype	**npp2;
116 {
117     return (*npp1) -> toporder - (*npp2) -> toporder;
118 }
119 
120 nltype **
121 doarcs()
122 {
123     nltype	*parentp, **timesortnlp;
124     arctype	*arcp;
125     long	index;
126     long	pass;
127 
128 	/*
129 	 *	initialize various things:
130 	 *	    zero out child times.
131 	 *	    count self-recursive calls.
132 	 *	    indicate that nothing is on cycles.
133 	 */
134     for ( parentp = nl ; parentp < npe ; parentp++ ) {
135 	parentp -> childtime = 0.0;
136 	arcp = arclookup( parentp , parentp );
137 	if ( arcp != 0 ) {
138 	    parentp -> ncall -= arcp -> arc_count;
139 	    parentp -> selfcalls = arcp -> arc_count;
140 	} else {
141 	    parentp -> selfcalls = 0;
142 	}
143 	parentp -> npropcall = parentp -> ncall;
144 	parentp -> propfraction = 0.0;
145 	parentp -> propself = 0.0;
146 	parentp -> propchild = 0.0;
147 	parentp -> printflag = FALSE;
148 	parentp -> toporder = DFN_NAN;
149 	parentp -> cycleno = 0;
150 	parentp -> cyclehead = parentp;
151 	parentp -> cnext = 0;
152     }
153     for ( pass = 1 ; ; pass++ ) {
154 	    /*
155 	     *	topologically order things
156 	     *	if any node is unnumbered,
157 	     *	    number it and any of its descendents.
158 	     */
159 	for ( dfn_init() , parentp = nl ; parentp < npe ; parentp++ ) {
160 	    if ( parentp -> toporder == DFN_NAN ) {
161 		dfn( parentp );
162 	    }
163 	}
164 	    /*
165 	     *	link together nodes on the same cycle
166 	     */
167 	cyclelink();
168 	    /*
169 	     *	if no cycles to break up, proceed
170 	     */
171 	if ( ! Cflag )
172 	    break;
173 	    /*
174 	     *	analyze cycles to determine breakup
175 	     */
176 #	ifdef DEBUG
177 	    if ( debug & BREAKCYCLE ) {
178 		printf("[doarcs] pass %ld, cycle(s) %d\n" , pass , ncycle );
179 	    }
180 #	endif /* DEBUG */
181 	if ( pass == 1 ) {
182 	    printf( "\n\n%s %s\n%s %d:\n" ,
183 		"The following arcs were deleted" ,
184 		"from the propagation calculation" ,
185 		"to reduce the maximum cycle size to", cyclethreshold );
186 	}
187 	if ( cycleanalyze() )
188 	    break;
189 	free ( cyclenl );
190 	ncycle = 0;
191 	for ( parentp = nl ; parentp < npe ; parentp++ ) {
192 	    parentp -> toporder = DFN_NAN;
193 	    parentp -> cycleno = 0;
194 	    parentp -> cyclehead = parentp;
195 	    parentp -> cnext = 0;
196 	}
197     }
198     if ( pass > 1 ) {
199 	printf( "\f\n" );
200     } else {
201 	printf( "\tNone\n\n" );
202     }
203 	/*
204 	 *	Sort the symbol table in reverse topological order
205 	 */
206     topsortnlp = (nltype **) calloc( nname , sizeof(nltype *) );
207     if ( topsortnlp == (nltype **) 0 )
208 	errx( 1 , "[doarcs] ran out of memory for topo sorting" );
209     for ( index = 0 ; index < nname ; index += 1 ) {
210 	topsortnlp[ index ] = &nl[ index ];
211     }
212     qsort( topsortnlp , nname , sizeof(nltype *) , topcmp );
213 #   ifdef DEBUG
214 	if ( debug & DFNDEBUG ) {
215 	    printf( "[doarcs] topological sort listing\n" );
216 	    for ( index = 0 ; index < nname ; index += 1 ) {
217 		printf( "[doarcs] " );
218 		printf( "%d:" , topsortnlp[ index ] -> toporder );
219 		printname( topsortnlp[ index ] );
220 		printf( "\n" );
221 	    }
222 	}
223 #   endif /* DEBUG */
224 	/*
225 	 *	starting from the topological top,
226 	 *	propagate print flags to children.
227 	 *	also, calculate propagation fractions.
228 	 *	this happens before time propagation
229 	 *	since time propagation uses the fractions.
230 	 */
231     doflags();
232 	/*
233 	 *	starting from the topological bottom,
234 	 *	propagate children times up to parents.
235 	 */
236     dotime();
237 	/*
238 	 *	Now, sort by propself + propchild.
239 	 *	sorting both the regular function names
240 	 *	and cycle headers.
241 	 */
242     timesortnlp = (nltype **) calloc( nname + ncycle , sizeof(nltype *) );
243     if ( timesortnlp == (nltype **) 0 )
244 	errx( 1 , "ran out of memory for sorting" );
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 void
259 dotime()
260 {
261     int	index;
262 
263     cycletime();
264     for ( index = 0 ; index < nname ; index += 1 ) {
265 	timepropagate( topsortnlp[ index ] );
266     }
267 }
268 
269 void
270 timepropagate( parentp )
271     nltype	*parentp;
272 {
273     arctype	*arcp;
274     nltype	*childp;
275     double	share;
276     double	propshare;
277 
278     if ( parentp -> propfraction == 0.0 ) {
279 	return;
280     }
281 	/*
282 	 *	gather time from children of this parent.
283 	 */
284     for ( arcp = parentp -> children ; arcp ; arcp = arcp -> arc_childlist ) {
285 	childp = arcp -> arc_childp;
286 	if ( arcp -> arc_flags & DEADARC ) {
287 	    continue;
288 	}
289 	if ( arcp -> arc_count == 0 ) {
290 	    continue;
291 	}
292 	if ( childp == parentp ) {
293 	    continue;
294 	}
295 	if ( childp -> propfraction == 0.0 ) {
296 	    continue;
297 	}
298 	if ( childp -> cyclehead != childp ) {
299 	    if ( parentp -> cycleno == childp -> cycleno ) {
300 		continue;
301 	    }
302 	    if ( parentp -> toporder <= childp -> toporder ) {
303 		fprintf( stderr , "[propagate] toporder botches\n" );
304 	    }
305 	    childp = childp -> cyclehead;
306 	} else {
307 	    if ( parentp -> toporder <= childp -> toporder ) {
308 		fprintf( stderr , "[propagate] toporder botches\n" );
309 		continue;
310 	    }
311 	}
312 	if ( childp -> npropcall == 0 ) {
313 	    continue;
314 	}
315 	    /*
316 	     *	distribute time for this arc
317 	     */
318 	arcp -> arc_time = childp -> time
319 			        * ( ( (double) arcp -> arc_count ) /
320 				    ( (double) childp -> npropcall ) );
321 	arcp -> arc_childtime = childp -> childtime
322 			        * ( ( (double) arcp -> arc_count ) /
323 				    ( (double) childp -> npropcall ) );
324 	share = arcp -> arc_time + arcp -> arc_childtime;
325 	parentp -> childtime += share;
326 	    /*
327 	     *	( 1 - propfraction ) gets lost along the way
328 	     */
329 	propshare = parentp -> propfraction * share;
330 	    /*
331 	     *	fix things for printing
332 	     */
333 	parentp -> propchild += propshare;
334 	arcp -> arc_time *= parentp -> propfraction;
335 	arcp -> arc_childtime *= parentp -> propfraction;
336 	    /*
337 	     *	add this share to the parent's cycle header, if any.
338 	     */
339 	if ( parentp -> cyclehead != parentp ) {
340 	    parentp -> cyclehead -> childtime += share;
341 	    parentp -> cyclehead -> propchild += propshare;
342 	}
343 #	ifdef DEBUG
344 	    if ( debug & PROPDEBUG ) {
345 		printf( "[dotime] child \t" );
346 		printname( childp );
347 		printf( " with %f %f %ld/%ld\n" ,
348 			childp -> time , childp -> childtime ,
349 			arcp -> arc_count , childp -> npropcall );
350 		printf( "[dotime] parent\t" );
351 		printname( parentp );
352 		printf( "\n[dotime] share %f\n" , share );
353 	    }
354 #	endif /* DEBUG */
355     }
356 }
357 
358 void
359 cyclelink()
360 {
361     register nltype	*nlp;
362     register nltype	*cyclenlp;
363     int			cycle;
364     nltype		*memberp;
365     arctype		*arcp;
366 
367 	/*
368 	 *	Count the number of cycles, and initialize the cycle lists
369 	 */
370     ncycle = 0;
371     for ( nlp = nl ; nlp < npe ; nlp++ ) {
372 	    /*
373 	     *	this is how you find unattached cycles
374 	     */
375 	if ( nlp -> cyclehead == nlp && nlp -> cnext != 0 ) {
376 	    ncycle += 1;
377 	}
378     }
379 	/*
380 	 *	cyclenl is indexed by cycle number:
381 	 *	i.e. it is origin 1, not origin 0.
382 	 */
383     cyclenl = (nltype *) calloc( ncycle + 1 , sizeof( nltype ) );
384     if ( cyclenl == 0 )
385 	errx( 1 , "no room for %d bytes of cycle headers" ,
386 		   ( ncycle + 1 ) * sizeof( nltype ) );
387 	/*
388 	 *	now link cycles to true cycleheads,
389 	 *	number them, accumulate the data for the cycle
390 	 */
391     cycle = 0;
392     for ( nlp = nl ; nlp < npe ; nlp++ ) {
393 	if ( !( nlp -> cyclehead == nlp && nlp -> cnext != 0 ) ) {
394 	    continue;
395 	}
396 	cycle += 1;
397 	cyclenlp = &cyclenl[cycle];
398         cyclenlp -> name = 0;		/* the name */
399         cyclenlp -> value = 0;		/* the pc entry point */
400         cyclenlp -> time = 0.0;		/* ticks in this routine */
401         cyclenlp -> childtime = 0.0;	/* cumulative ticks in children */
402 	cyclenlp -> ncall = 0;		/* how many times called */
403 	cyclenlp -> selfcalls = 0;	/* how many calls to self */
404 	cyclenlp -> propfraction = 0.0;	/* what % of time propagates */
405 	cyclenlp -> propself = 0.0;	/* how much self time propagates */
406 	cyclenlp -> propchild = 0.0;	/* how much child time propagates */
407 	cyclenlp -> printflag = TRUE;	/* should this be printed? */
408 	cyclenlp -> index = 0;		/* index in the graph list */
409 	cyclenlp -> toporder = DFN_NAN;	/* graph call chain top-sort order */
410 	cyclenlp -> cycleno = cycle;	/* internal number of cycle on */
411 	cyclenlp -> cyclehead = cyclenlp;	/* pointer to head of cycle */
412 	cyclenlp -> cnext = nlp;	/* pointer to next member of cycle */
413 	cyclenlp -> parents = 0;	/* list of caller arcs */
414 	cyclenlp -> children = 0;	/* list of callee arcs */
415 #	ifdef DEBUG
416 	    if ( debug & CYCLEDEBUG ) {
417 		printf( "[cyclelink] " );
418 		printname( nlp );
419 		printf( " is the head of cycle %d\n" , cycle );
420 	    }
421 #	endif /* DEBUG */
422 	    /*
423 	     *	link members to cycle header
424 	     */
425 	for ( memberp = nlp ; memberp ; memberp = memberp -> cnext ) {
426 	    memberp -> cycleno = cycle;
427 	    memberp -> cyclehead = cyclenlp;
428 	}
429 	    /*
430 	     *	count calls from outside the cycle
431 	     *	and those among cycle members
432 	     */
433 	for ( memberp = nlp ; memberp ; memberp = memberp -> cnext ) {
434 	    for ( arcp=memberp->parents ; arcp ; arcp=arcp->arc_parentlist ) {
435 		if ( arcp -> arc_parentp == memberp ) {
436 		    continue;
437 		}
438 		if ( arcp -> arc_parentp -> cycleno == cycle ) {
439 		    cyclenlp -> selfcalls += arcp -> arc_count;
440 		} else {
441 		    cyclenlp -> npropcall += arcp -> arc_count;
442 		}
443 	    }
444 	}
445     }
446 }
447 
448     /*
449      *	analyze cycles to determine breakup
450      */
451 bool
452 cycleanalyze()
453 {
454     arctype	**cyclestack;
455     arctype	**stkp;
456     arctype	**arcpp;
457     arctype	**endlist;
458     arctype	*arcp;
459     nltype	*nlp;
460     cltype	*clp;
461     bool	ret;
462     bool	done;
463     int		size;
464     int		cycleno;
465 
466 	/*
467 	 *	calculate the size of the cycle, and find nodes that
468 	 *	exit the cycle as they are desirable targets to cut
469 	 *	some of their parents
470 	 */
471     for ( done = TRUE , cycleno = 1 ; cycleno <= ncycle ; cycleno++ ) {
472 	size = 0;
473 	for (nlp = cyclenl[ cycleno ] . cnext; nlp; nlp = nlp -> cnext) {
474 	    size += 1;
475 	    nlp -> parentcnt = 0;
476 	    nlp -> flags &= ~HASCYCLEXIT;
477 	    for ( arcp = nlp -> parents; arcp; arcp = arcp -> arc_parentlist ) {
478 		nlp -> parentcnt += 1;
479 		if ( arcp -> arc_parentp -> cycleno != cycleno )
480 		    nlp -> flags |= HASCYCLEXIT;
481 	    }
482 	}
483 	if ( size <= cyclethreshold )
484 	    continue;
485 	done = FALSE;
486         cyclestack = (arctype **) calloc( size + 1 , sizeof( arctype *) );
487 	if ( cyclestack == 0 )
488 	    errx( 1, "no room for %d bytes of cycle stack" ,
489 			   ( size + 1 ) * sizeof( arctype * ) );
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 bool
528 descend( node , stkstart , stkp )
529     nltype	*node;
530     arctype	**stkstart;
531     arctype	**stkp;
532 {
533     arctype	*arcp;
534     bool	ret;
535 
536     for ( arcp = node -> children ; arcp ; arcp = arcp -> arc_childlist ) {
537 #	ifdef DEBUG
538 	    visited++;
539 #	endif /* DEBUG */
540 	if ( arcp -> arc_childp -> cycleno != node -> cycleno
541 	    || ( arcp -> arc_childp -> flags & VISITED )
542 	    || ( arcp -> arc_flags & DEADARC ) )
543 	    continue;
544 #	ifdef DEBUG
545 	    viable++;
546 #	endif /* DEBUG */
547 	*stkp = arcp;
548 	if ( arcp -> arc_childp -> flags & CYCLEHEAD ) {
549 	    if ( addcycle( stkstart , stkp ) == FALSE )
550 		return( FALSE );
551 	    continue;
552 	}
553 	arcp -> arc_childp -> flags |= VISITED;
554 	ret = descend( arcp -> arc_childp , stkstart , stkp + 1 );
555 	arcp -> arc_childp -> flags &= ~VISITED;
556 	if ( ret == FALSE )
557 	    return( FALSE );
558     }
559     return( TRUE );
560 }
561 
562 bool
563 addcycle( stkstart , stkend )
564     arctype	**stkstart;
565     arctype	**stkend;
566 {
567     arctype	**arcpp;
568     arctype	**stkloc;
569     arctype	**stkp;
570     arctype	**endlist;
571     arctype	*minarc;
572     arctype	*arcp;
573     cltype	*clp;
574     int		size;
575 
576     size = stkend - stkstart + 1;
577     if ( size <= 1 )
578 	return( TRUE );
579     for ( arcpp = stkstart , minarc = *arcpp ; arcpp <= stkend ; arcpp++ ) {
580 	if ( *arcpp > minarc )
581 	    continue;
582 	minarc = *arcpp;
583 	stkloc = arcpp;
584     }
585     for ( clp = cyclehead ; clp ; clp = clp -> next ) {
586 	if ( clp -> size != size )
587 	    continue;
588 	stkp = stkloc;
589 	endlist = &clp -> list[ size ];
590 	for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ ) {
591 	    if ( *stkp++ != *arcpp )
592 		break;
593 	    if ( stkp > stkend )
594 		stkp = stkstart;
595 	}
596 	if ( arcpp == endlist ) {
597 #	    ifdef DEBUG
598 		oldcycle++;
599 #	    endif /* DEBUG */
600 	    return( TRUE );
601 	}
602     }
603     clp = (cltype *)
604 	calloc( 1 , sizeof ( cltype ) + ( size - 1 ) * sizeof( arctype * ) );
605     if ( clp == 0 ) {
606 	warnx( "no room for %d bytes of subcycle storage" ,
607 	    sizeof ( cltype ) + ( size - 1 ) * sizeof( arctype * ) );
608 	return( FALSE );
609     }
610     stkp = stkloc;
611     endlist = &clp -> list[ size ];
612     for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ ) {
613 	arcp = *arcpp = *stkp++;
614 	if ( stkp > stkend )
615 	    stkp = stkstart;
616 	arcp -> arc_cyclecnt++;
617 	if ( ( arcp -> arc_flags & ONLIST ) == 0 ) {
618 	    arcp -> arc_flags |= ONLIST;
619 	    arcp -> arc_next = archead;
620 	    archead = arcp;
621 	}
622     }
623     clp -> size = size;
624     clp -> next = cyclehead;
625     cyclehead = clp;
626 #   ifdef DEBUG
627 	newcycle++;
628 	if ( debug & SUBCYCLELIST ) {
629 	    printsubcycle( clp );
630 	}
631 #   endif /* DEBUG */
632     cyclecnt++;
633     if ( cyclecnt >= CYCLEMAX )
634 	return( FALSE );
635     return( TRUE );
636 }
637 
638 void
639 compresslist()
640 {
641     cltype	*clp;
642     cltype	**prev;
643     arctype	**arcpp;
644     arctype	**endlist;
645     arctype	*arcp;
646     arctype	*maxarcp;
647     arctype	*maxexitarcp;
648     arctype	*maxwithparentarcp;
649     arctype	*maxnoparentarcp;
650     int		maxexitcnt;
651     int		maxwithparentcnt;
652     int		maxnoparentcnt;
653 #   ifdef DEBUG
654 	const char	*type;
655 #   endif /* DEBUG */
656 
657     maxexitcnt = 0;
658     maxwithparentcnt = 0;
659     maxnoparentcnt = 0;
660     for ( endlist = &archead , arcp = archead ; arcp ; ) {
661 	if ( arcp -> arc_cyclecnt == 0 ) {
662 	    arcp -> arc_flags &= ~ONLIST;
663 	    *endlist = arcp -> arc_next;
664 	    arcp -> arc_next = 0;
665 	    arcp = *endlist;
666 	    continue;
667 	}
668 	if ( arcp -> arc_childp -> flags & HASCYCLEXIT ) {
669 	    if ( arcp -> arc_cyclecnt > maxexitcnt ||
670 		( arcp -> arc_cyclecnt == maxexitcnt &&
671 		arcp -> arc_cyclecnt < maxexitarcp -> arc_count ) ) {
672 		maxexitcnt = arcp -> arc_cyclecnt;
673 		maxexitarcp = arcp;
674 	    }
675 	} else if ( arcp -> arc_childp -> parentcnt > 1 ) {
676 	    if ( arcp -> arc_cyclecnt > maxwithparentcnt ||
677 		( arcp -> arc_cyclecnt == maxwithparentcnt &&
678 		arcp -> arc_cyclecnt < maxwithparentarcp -> arc_count ) ) {
679 		maxwithparentcnt = arcp -> arc_cyclecnt;
680 		maxwithparentarcp = arcp;
681 	    }
682 	} else {
683 	    if ( arcp -> arc_cyclecnt > maxnoparentcnt ||
684 		( arcp -> arc_cyclecnt == maxnoparentcnt &&
685 		arcp -> arc_cyclecnt < maxnoparentarcp -> arc_count ) ) {
686 		maxnoparentcnt = arcp -> arc_cyclecnt;
687 		maxnoparentarcp = arcp;
688 	    }
689 	}
690 	endlist = &arcp -> arc_next;
691 	arcp = arcp -> arc_next;
692     }
693     if ( maxexitcnt > 0 ) {
694 	/*
695 	 *	first choice is edge leading to node with out-of-cycle parent
696 	 */
697 	maxarcp = maxexitarcp;
698 #	ifdef DEBUG
699 	    type = "exit";
700 #	endif /* DEBUG */
701     } else if ( maxwithparentcnt > 0 ) {
702 	/*
703 	 *	second choice is edge leading to node with at least one
704 	 *	other in-cycle parent
705 	 */
706 	maxarcp = maxwithparentarcp;
707 #	ifdef DEBUG
708 	    type = "internal";
709 #	endif /* DEBUG */
710     } else {
711 	/*
712 	 *	last choice is edge leading to node with only this arc as
713 	 *	a parent (as it will now be orphaned)
714 	 */
715 	maxarcp = maxnoparentarcp;
716 #	ifdef DEBUG
717 	    type = "orphan";
718 #	endif /* DEBUG */
719     }
720     maxarcp -> arc_flags |= DEADARC;
721     maxarcp -> arc_childp -> parentcnt -= 1;
722     maxarcp -> arc_childp -> npropcall -= maxarcp -> arc_count;
723 #   ifdef DEBUG
724 	if ( debug & BREAKCYCLE ) {
725 	    printf( "%s delete %s arc: %s (%ld) -> %s from %u cycle(s)\n" ,
726 		"[compresslist]" , type , maxarcp -> arc_parentp -> name ,
727 		maxarcp -> arc_count , maxarcp -> arc_childp -> name ,
728 		maxarcp -> arc_cyclecnt );
729 	}
730 #   endif /* DEBUG */
731     printf( "\t%s to %s with %ld calls\n" , maxarcp -> arc_parentp -> name ,
732 	maxarcp -> arc_childp -> name , maxarcp -> arc_count );
733     prev = &cyclehead;
734     for ( clp = cyclehead ; clp ; ) {
735 	endlist = &clp -> list[ clp -> size ];
736 	for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ )
737 	    if ( (*arcpp) -> arc_flags & DEADARC )
738 		break;
739 	if ( arcpp == endlist ) {
740 	    prev = &clp -> next;
741 	    clp = clp -> next;
742 	    continue;
743 	}
744 	for ( arcpp = clp -> list ; arcpp < endlist ; arcpp++ )
745 	    (*arcpp) -> arc_cyclecnt--;
746 	cyclecnt--;
747 	*prev = clp -> next;
748 	clp = clp -> next;
749 	free( clp );
750     }
751 }
752 
753 #ifdef DEBUG
754 void
755 printsubcycle( clp )
756     cltype	*clp;
757 {
758     arctype	**arcpp;
759     arctype	**endlist;
760 
761     arcpp = clp -> list;
762     printf( "%s <cycle %d>\n" , (*arcpp) -> arc_parentp -> name ,
763 	(*arcpp) -> arc_parentp -> cycleno ) ;
764     for ( endlist = &clp -> list[ clp -> size ]; arcpp < endlist ; arcpp++ )
765 	printf( "\t(%ld) -> %s\n" , (*arcpp) -> arc_count ,
766 	    (*arcpp) -> arc_childp -> name ) ;
767 }
768 #endif /* DEBUG */
769 
770 void
771 cycletime()
772 {
773     int			cycle;
774     nltype		*cyclenlp;
775     nltype		*childp;
776 
777     for ( cycle = 1 ; cycle <= ncycle ; cycle += 1 ) {
778 	cyclenlp = &cyclenl[ cycle ];
779 	for ( childp = cyclenlp -> cnext ; childp ; childp = childp -> cnext ) {
780 	    if ( childp -> propfraction == 0.0 ) {
781 		    /*
782 		     * all members have the same propfraction except those
783 		     *	that were excluded with -E
784 		     */
785 		continue;
786 	    }
787 	    cyclenlp -> time += childp -> time;
788 	}
789 	cyclenlp -> propself = cyclenlp -> propfraction * cyclenlp -> time;
790     }
791 }
792 
793     /*
794      *	in one top to bottom pass over the topologically sorted namelist
795      *	propagate:
796      *		printflag as the union of parents' printflags
797      *		propfraction as the sum of fractional parents' propfractions
798      *	and while we're here, sum time for functions.
799      */
800 void
801 doflags()
802 {
803     int		index;
804     nltype	*childp;
805     nltype	*oldhead;
806 
807     oldhead = 0;
808     for ( index = nname-1 ; index >= 0 ; index -= 1 ) {
809 	childp = topsortnlp[ index ];
810 	    /*
811 	     *	if we haven't done this function or cycle,
812 	     *	inherit things from parent.
813 	     *	this way, we are linear in the number of arcs
814 	     *	since we do all members of a cycle (and the cycle itself)
815 	     *	as we hit the first member of the cycle.
816 	     */
817 	if ( childp -> cyclehead != oldhead ) {
818 	    oldhead = childp -> cyclehead;
819 	    inheritflags( childp );
820 	}
821 #	ifdef DEBUG
822 	    if ( debug & PROPDEBUG ) {
823 		printf( "[doflags] " );
824 		printname( childp );
825 		printf( " inherits printflag %d and propfraction %f\n" ,
826 			childp -> printflag , childp -> propfraction );
827 	    }
828 #	endif /* DEBUG */
829 	if ( ! childp -> printflag ) {
830 		/*
831 		 *	printflag is off
832 		 *	it gets turned on by
833 		 *	being on -f list,
834 		 *	or there not being any -f list and not being on -e list.
835 		 */
836 	    if (   onlist( flist , childp -> name )
837 		|| ( !fflag && !onlist( elist , childp -> name ) ) ) {
838 		childp -> printflag = TRUE;
839 	    }
840 	} else {
841 		/*
842 		 *	this function has printing parents:
843 		 *	maybe someone wants to shut it up
844 		 *	by putting it on -e list.  (but favor -f over -e)
845 		 */
846 	    if (  ( !onlist( flist , childp -> name ) )
847 		&& onlist( elist , childp -> name ) ) {
848 		childp -> printflag = FALSE;
849 	    }
850 	}
851 	if ( childp -> propfraction == 0.0 ) {
852 		/*
853 		 *	no parents to pass time to.
854 		 *	collect time from children if
855 		 *	its on -F list,
856 		 *	or there isn't any -F list and its not on -E list.
857 		 */
858 	    if ( onlist( Flist , childp -> name )
859 		|| ( !Fflag && !onlist( Elist , childp -> name ) ) ) {
860 		    childp -> propfraction = 1.0;
861 	    }
862 	} else {
863 		/*
864 		 *	it has parents to pass time to,
865 		 *	but maybe someone wants to shut it up
866 		 *	by putting it on -E list.  (but favor -F over -E)
867 		 */
868 	    if (  !onlist( Flist , childp -> name )
869 		&& onlist( Elist , childp -> name ) ) {
870 		childp -> propfraction = 0.0;
871 	    }
872 	}
873 	childp -> propself = childp -> time * childp -> propfraction;
874 	printtime += childp -> propself;
875 #	ifdef DEBUG
876 	    if ( debug & PROPDEBUG ) {
877 		printf( "[doflags] " );
878 		printname( childp );
879 		printf( " ends up with printflag %d and propfraction %f\n" ,
880 			childp -> printflag , childp -> propfraction );
881 		printf( "time %f propself %f printtime %f\n" ,
882 			childp -> time , childp -> propself , printtime );
883 	    }
884 #	endif /* DEBUG */
885     }
886 }
887 
888     /*
889      *	check if any parent of this child
890      *	(or outside parents of this cycle)
891      *	have their print flags on and set the
892      *	print flag of the child (cycle) appropriately.
893      *	similarly, deal with propagation fractions from parents.
894      */
895 void
896 inheritflags( childp )
897     nltype	*childp;
898 {
899     nltype	*headp;
900     arctype	*arcp;
901     nltype	*parentp;
902     nltype	*memp;
903 
904     headp = childp -> cyclehead;
905     if ( childp == headp ) {
906 	    /*
907 	     *	just a regular child, check its parents
908 	     */
909 	childp -> printflag = FALSE;
910 	childp -> propfraction = 0.0;
911 	for (arcp = childp -> parents ; arcp ; arcp = arcp -> arc_parentlist) {
912 	    parentp = arcp -> arc_parentp;
913 	    if ( childp == parentp ) {
914 		continue;
915 	    }
916 	    childp -> printflag |= parentp -> printflag;
917 		/*
918 		 *	if the child was never actually called
919 		 *	(e.g. this arc is static (and all others are, too))
920 		 *	no time propagates along this arc.
921 		 */
922 	    if ( arcp -> arc_flags & DEADARC ) {
923 		continue;
924 	    }
925 	    if ( childp -> npropcall ) {
926 		childp -> propfraction += parentp -> propfraction
927 					* ( ( (double) arcp -> arc_count )
928 					  / ( (double) childp -> npropcall ) );
929 	    }
930 	}
931     } else {
932 	    /*
933 	     *	its a member of a cycle, look at all parents from
934 	     *	outside the cycle
935 	     */
936 	headp -> printflag = FALSE;
937 	headp -> propfraction = 0.0;
938 	for ( memp = headp -> cnext ; memp ; memp = memp -> cnext ) {
939 	    for (arcp = memp->parents ; arcp ; arcp = arcp->arc_parentlist) {
940 		if ( arcp -> arc_parentp -> cyclehead == headp ) {
941 		    continue;
942 		}
943 		parentp = arcp -> arc_parentp;
944 		headp -> printflag |= parentp -> printflag;
945 		    /*
946 		     *	if the cycle was never actually called
947 		     *	(e.g. this arc is static (and all others are, too))
948 		     *	no time propagates along this arc.
949 		     */
950 		if ( arcp -> arc_flags & DEADARC ) {
951 		    continue;
952 		}
953 		if ( headp -> npropcall ) {
954 		    headp -> propfraction += parentp -> propfraction
955 					* ( ( (double) arcp -> arc_count )
956 					  / ( (double) headp -> npropcall ) );
957 		}
958 	    }
959 	}
960 	for ( memp = headp ; memp ; memp = memp -> cnext ) {
961 	    memp -> printflag = headp -> printflag;
962 	    memp -> propfraction = headp -> propfraction;
963 	}
964     }
965 }
966