xref: /freebsd/usr.bin/gprof/gprof.c (revision 732a02b4e77866604a120a275c082bb6221bd2ff)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef lint
33 static const char copyright[] =
34 "@(#) Copyright (c) 1983, 1993\n\
35 	The Regents of the University of California.  All rights reserved.\n";
36 #endif /* not lint */
37 
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)gprof.c	8.1 (Berkeley) 6/6/93";
41 #endif /* not lint */
42 #endif
43 
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD$");
46 
47 #include <err.h>
48 #include <limits.h>
49 #include <stdint.h>
50 #include <string.h>
51 
52 #define	EXTERN
53 #include "gprof.h"
54 
55 static int valcmp(const void *, const void *);
56 
57 static struct gmonhdr	gmonhdr;
58 static int lflag;
59 static int Lflag;
60 
61 int
62 main(int argc, char **argv)
63 {
64     char	**sp;
65     nltype	**timesortnlp;
66     char	**defaultEs;
67 
68     --argc;
69     argv++;
70     debug = 0;
71     bflag = TRUE;
72     while ( *argv != 0 && **argv == '-' ) {
73 	(*argv)++;
74 	switch ( **argv ) {
75 	case 'a':
76 	    aflag = TRUE;
77 	    break;
78 	case 'b':
79 	    bflag = FALSE;
80 	    break;
81 	case 'C':
82 	    Cflag = TRUE;
83 	    cyclethreshold = atoi( *++argv );
84 	    break;
85 	case 'd':
86 	    dflag = TRUE;
87 	    setlinebuf(stdout);
88 	    debug |= atoi( *++argv );
89 	    debug |= ANYDEBUG;
90 #	    ifdef DEBUG
91 		printf("[main] debug = %d\n", debug);
92 #	    else /* not DEBUG */
93 		printf("gprof: -d ignored\n");
94 #	    endif /* DEBUG */
95 	    break;
96 	case 'E':
97 	    ++argv;
98 	    addlist( Elist , *argv );
99 	    Eflag = TRUE;
100 	    addlist( elist , *argv );
101 	    eflag = TRUE;
102 	    break;
103 	case 'e':
104 	    addlist( elist , *++argv );
105 	    eflag = TRUE;
106 	    break;
107 	case 'F':
108 	    ++argv;
109 	    addlist( Flist , *argv );
110 	    Fflag = TRUE;
111 	    addlist( flist , *argv );
112 	    fflag = TRUE;
113 	    break;
114 	case 'f':
115 	    addlist( flist , *++argv );
116 	    fflag = TRUE;
117 	    break;
118 	case 'k':
119 	    addlist( kfromlist , *++argv );
120 	    addlist( ktolist , *++argv );
121 	    kflag = TRUE;
122 	    break;
123 	case 'K':
124 	    Kflag = TRUE;
125 	    break;
126 	case 'l':
127 	    lflag = 1;
128 	    Lflag = 0;
129 	    break;
130 	case 'L':
131 	    Lflag = 1;
132 	    lflag = 0;
133 	    break;
134 	case 's':
135 	    sflag = TRUE;
136 	    break;
137 	case 'u':
138 	    uflag = TRUE;
139 	    break;
140 	case 'z':
141 	    zflag = TRUE;
142 	    break;
143 	}
144 	argv++;
145     }
146     if ( *argv != 0 ) {
147 	a_outname  = *argv;
148 	argv++;
149     } else {
150 	a_outname  = A_OUTNAME;
151     }
152     if ( *argv != 0 ) {
153 	gmonname = *argv;
154 	argv++;
155     } else {
156 	gmonname = (char *) malloc(strlen(a_outname)+6);
157 	strcpy(gmonname, a_outname);
158 	strcat(gmonname, ".gmon");
159     }
160 	/*
161 	 *	get information from the executable file.
162 	 */
163     if ((Kflag && kernel_getnfile(a_outname, &defaultEs) == -1) ||
164       (!Kflag && elf_getnfile(a_outname, &defaultEs) == -1
165 #ifdef WITH_AOUT
166       && aout_getnfile(a_outname, &defaultEs) == -1
167 #endif
168       ))
169 	errx(1, "%s: bad format", a_outname);
170 	/*
171 	 *	sort symbol table.
172 	 */
173     qsort(nl, nname, sizeof(nltype), valcmp);
174 	/*
175 	 *	turn off default functions
176 	 */
177     for ( sp = defaultEs ; *sp ; sp++ ) {
178 	Eflag = TRUE;
179 	addlist( Elist , *sp );
180 	eflag = TRUE;
181 	addlist( elist , *sp );
182     }
183 	/*
184 	 *	get information about mon.out file(s).
185 	 */
186     do	{
187 	getpfile( gmonname );
188 	if ( *argv != 0 ) {
189 	    gmonname = *argv;
190 	}
191     } while ( *argv++ != 0 );
192 	/*
193 	 *	how many ticks per second?
194 	 *	if we can't tell, report time in ticks.
195 	 */
196     if (hz == 0) {
197 	hz = 1;
198 	fprintf(stderr, "time is in ticks, not seconds\n");
199     }
200 	/*
201 	 *	dump out a gmon.sum file if requested
202 	 */
203     if ( sflag ) {
204 	dumpsum( GMONSUM );
205     }
206 	/*
207 	 *	assign samples to procedures
208 	 */
209     asgnsamples();
210 	/*
211 	 *	assemble the dynamic profile
212 	 */
213     timesortnlp = doarcs();
214 	/*
215 	 *	print the dynamic profile
216 	 */
217     if(!lflag) {
218 	    printgprof( timesortnlp );
219     }
220 	/*
221 	 *	print the flat profile
222 	 */
223     if(!Lflag) {
224 	    printprof();
225     }
226 	/*
227 	 *	print the index
228 	 */
229     printindex();
230     exit(0);
231 }
232 
233     /*
234      *	information from a gmon.out file is in two parts:
235      *	an array of sampling hits within pc ranges,
236      *	and the arcs.
237      */
238 void
239 getpfile(char *filename)
240 {
241     FILE		*pfile;
242     struct rawarc	arc;
243 
244     pfile = openpfile(filename);
245     readsamples(pfile);
246 	/*
247 	 *	the rest of the file consists of
248 	 *	a bunch of <from,self,count> tuples.
249 	 */
250     while ( fread( &arc , sizeof arc , 1 , pfile ) == 1 ) {
251 #	ifdef DEBUG
252 	    if ( debug & SAMPLEDEBUG ) {
253 		printf( "[getpfile] frompc 0x%lx selfpc 0x%lx count %ld\n" ,
254 			arc.raw_frompc , arc.raw_selfpc , arc.raw_count );
255 	    }
256 #	endif /* DEBUG */
257 	    /*
258 	     *	add this arc
259 	     */
260 	tally( &arc );
261     }
262     fclose(pfile);
263 }
264 
265 FILE *
266 openpfile(char *filename)
267 {
268     struct gmonhdr	tmp;
269     FILE		*pfile;
270     int			size;
271     int			rate;
272 
273     if((pfile = fopen(filename, "r")) == NULL)
274 	err(1, "%s", filename);
275     fread(&tmp, sizeof(struct gmonhdr), 1, pfile);
276     if ( s_highpc != 0 && ( tmp.lpc != gmonhdr.lpc ||
277 	 tmp.hpc != gmonhdr.hpc || tmp.ncnt != gmonhdr.ncnt ) )
278 	errx(1, "%s: incompatible with first gmon file", filename);
279     gmonhdr = tmp;
280     if ( gmonhdr.version == GMONVERSION ) {
281 	rate = gmonhdr.profrate;
282 	size = sizeof(struct gmonhdr);
283     } else {
284 	fseek(pfile, sizeof(struct ophdr), SEEK_SET);
285 	size = sizeof(struct ophdr);
286 	gmonhdr.profrate = rate = hertz();
287 	gmonhdr.version = GMONVERSION;
288     }
289     if (hz == 0) {
290 	hz = rate;
291     } else if (hz != rate)
292 	errx(0, "%s: profile clock rate (%d) %s (%ld) in first gmon file",
293 	    filename, rate, "incompatible with clock rate", hz);
294     if ( gmonhdr.histcounter_type == 0 ) {
295 	/* Historical case.  The type was u_short (2 bytes in practice). */
296 	histcounter_type = 16;
297 	histcounter_size = 2;
298     } else {
299 	histcounter_type = gmonhdr.histcounter_type;
300 	histcounter_size = abs(histcounter_type) / CHAR_BIT;
301     }
302     s_lowpc = (unsigned long) gmonhdr.lpc;
303     s_highpc = (unsigned long) gmonhdr.hpc;
304     lowpc = (unsigned long)gmonhdr.lpc / HISTORICAL_SCALE_2;
305     highpc = (unsigned long)gmonhdr.hpc / HISTORICAL_SCALE_2;
306     sampbytes = gmonhdr.ncnt - size;
307     nsamples = sampbytes / histcounter_size;
308 #   ifdef DEBUG
309 	if ( debug & SAMPLEDEBUG ) {
310 	    printf( "[openpfile] hdr.lpc 0x%lx hdr.hpc 0x%lx hdr.ncnt %d\n",
311 		gmonhdr.lpc , gmonhdr.hpc , gmonhdr.ncnt );
312 	    printf( "[openpfile]   s_lowpc 0x%lx   s_highpc 0x%lx\n" ,
313 		s_lowpc , s_highpc );
314 	    printf( "[openpfile]     lowpc 0x%lx     highpc 0x%lx\n" ,
315 		lowpc , highpc );
316 	    printf( "[openpfile] sampbytes %d nsamples %d\n" ,
317 		sampbytes , nsamples );
318 	    printf( "[openpfile] sample rate %ld\n" , hz );
319 	}
320 #   endif /* DEBUG */
321     return(pfile);
322 }
323 
324 void
325 tally(struct rawarc *rawp)
326 {
327     nltype		*parentp;
328     nltype		*childp;
329 
330     parentp = nllookup( rawp -> raw_frompc );
331     childp = nllookup( rawp -> raw_selfpc );
332     if ( parentp == 0 || childp == 0 )
333 	return;
334     if ( kflag
335 	 && onlist( kfromlist , parentp -> name )
336 	 && onlist( ktolist , childp -> name ) ) {
337 	return;
338     }
339     childp -> ncall += rawp -> raw_count;
340 #   ifdef DEBUG
341 	if ( debug & TALLYDEBUG ) {
342 	    printf( "[tally] arc from %s to %s traversed %ld times\n" ,
343 		    parentp -> name , childp -> name , rawp -> raw_count );
344 	}
345 #   endif /* DEBUG */
346     addarc( parentp , childp , rawp -> raw_count );
347 }
348 
349 /*
350  * dump out the gmon.sum file
351  */
352 void
353 dumpsum(const char *sumfile)
354 {
355     register nltype *nlp;
356     register arctype *arcp;
357     struct rawarc arc;
358     FILE *sfile;
359 
360     if ( ( sfile = fopen ( sumfile , "w" ) ) == NULL )
361 	err( 1 , "%s" , sumfile );
362     /*
363      * dump the header; use the last header read in
364      */
365     if ( fwrite( &gmonhdr , sizeof gmonhdr , 1 , sfile ) != 1 )
366 	err( 1 , "%s" , sumfile );
367     /*
368      * dump the samples
369      */
370     if (fwrite(samples, histcounter_size, nsamples, sfile) != nsamples)
371 	err( 1 , "%s" , sumfile );
372     /*
373      * dump the normalized raw arc information
374      */
375     for ( nlp = nl ; nlp < npe ; nlp++ ) {
376 	for ( arcp = nlp -> children ; arcp ; arcp = arcp -> arc_childlist ) {
377 	    arc.raw_frompc = arcp -> arc_parentp -> value;
378 	    arc.raw_selfpc = arcp -> arc_childp -> value;
379 	    arc.raw_count = arcp -> arc_count;
380 	    if ( fwrite ( &arc , sizeof arc , 1 , sfile ) != 1 )
381 		err( 1 , "%s" , sumfile );
382 #	    ifdef DEBUG
383 		if ( debug & SAMPLEDEBUG ) {
384 		    printf( "[dumpsum] frompc 0x%lx selfpc 0x%lx count %ld\n" ,
385 			    arc.raw_frompc , arc.raw_selfpc , arc.raw_count );
386 		}
387 #	    endif /* DEBUG */
388 	}
389     }
390     fclose( sfile );
391 }
392 
393 static int
394 valcmp(const void *v1, const void *v2)
395 {
396     const nltype *p1 = (const nltype *)v1;
397     const nltype *p2 = (const nltype *)v2;
398 
399     if ( p1 -> value < p2 -> value ) {
400 	return LESSTHAN;
401     }
402     if ( p1 -> value > p2 -> value ) {
403 	return GREATERTHAN;
404     }
405     return EQUALTO;
406 }
407 
408 void
409 readsamples(FILE *pfile)
410 {
411     int		i;
412     intmax_t	sample;
413 
414     if (samples == 0) {
415 	samples = (double *) calloc(nsamples, sizeof(double));
416 	if (samples == NULL)
417 	    errx(0, "no room for %d sample pc's", nsamples);
418     }
419     for (i = 0; i < nsamples; i++) {
420 	fread(&sample, histcounter_size, 1, pfile);
421 	if (feof(pfile))
422 		break;
423 	switch ( histcounter_type ) {
424 	case -8:
425 	    samples[i] += *(int8_t *)&sample;
426 	    break;
427 	case 8:
428 	    samples[i] += *(u_int8_t *)&sample;
429 	    break;
430 	case -16:
431 	    samples[i] += *(int16_t *)&sample;
432 	    break;
433 	case 16:
434 	    samples[i] += *(u_int16_t *)&sample;
435 	    break;
436 	case -32:
437 	    samples[i] += *(int32_t *)&sample;
438 	    break;
439 	case 32:
440 	    samples[i] += *(u_int32_t *)&sample;
441 	    break;
442 	case -64:
443 	    samples[i] += *(int64_t *)&sample;
444 	    break;
445 	case 64:
446 	    samples[i] += *(u_int64_t *)&sample;
447 	    break;
448 	default:
449 	    err(1, "unsupported histogram counter type %d", histcounter_type);
450 	}
451     }
452     if (i != nsamples)
453 	errx(1, "unexpected EOF after reading %d/%d samples", --i , nsamples );
454 }
455 
456 /*
457  *	Assign samples to the procedures to which they belong.
458  *
459  *	There are three cases as to where pcl and pch can be
460  *	with respect to the routine entry addresses svalue0 and svalue1
461  *	as shown in the following diagram.  overlap computes the
462  *	distance between the arrows, the fraction of the sample
463  *	that is to be credited to the routine which starts at svalue0.
464  *
465  *	    svalue0                                         svalue1
466  *	       |                                               |
467  *	       v                                               v
468  *
469  *	       +-----------------------------------------------+
470  *	       |					       |
471  *	  |  ->|    |<-		->|         |<-		->|    |<-  |
472  *	  |         |		  |         |		  |         |
473  *	  +---------+		  +---------+		  +---------+
474  *
475  *	  ^         ^		  ^         ^		  ^         ^
476  *	  |         |		  |         |		  |         |
477  *	 pcl       pch		 pcl       pch		 pcl       pch
478  *
479  *	For the vax we assert that samples will never fall in the first
480  *	two bytes of any routine, since that is the entry mask,
481  *	thus we give call alignentries() to adjust the entry points if
482  *	the entry mask falls in one bucket but the code for the routine
483  *	doesn't start until the next bucket.  In conjunction with the
484  *	alignment of routine addresses, this should allow us to have
485  *	only one sample for every four bytes of text space and never
486  *	have any overlap (the two end cases, above).
487  */
488 void
489 asgnsamples(void)
490 {
491     register int	j;
492     double		ccnt;
493     double		thetime;
494     unsigned long	pcl, pch;
495     register int	i;
496     unsigned long	overlap;
497     unsigned long	svalue0, svalue1;
498 
499     /* read samples and assign to namelist symbols */
500     scale = highpc - lowpc;
501     scale /= nsamples;
502     alignentries();
503     for (i = 0, j = 1; i < nsamples; i++) {
504 	ccnt = samples[i];
505 	if (ccnt == 0)
506 		continue;
507 	pcl = lowpc + (unsigned long)(scale * i);
508 	pch = lowpc + (unsigned long)(scale * (i + 1));
509 	thetime = ccnt;
510 #	ifdef DEBUG
511 	    if ( debug & SAMPLEDEBUG ) {
512 		printf( "[asgnsamples] pcl 0x%lx pch 0x%lx ccnt %.0f\n" ,
513 			pcl , pch , ccnt );
514 	    }
515 #	endif /* DEBUG */
516 	totime += thetime;
517 	for (j = j - 1; j < nname; j++) {
518 	    svalue0 = nl[j].svalue;
519 	    svalue1 = nl[j+1].svalue;
520 		/*
521 		 *	if high end of tick is below entry address,
522 		 *	go for next tick.
523 		 */
524 	    if (pch < svalue0)
525 		    break;
526 		/*
527 		 *	if low end of tick into next routine,
528 		 *	go for next routine.
529 		 */
530 	    if (pcl >= svalue1)
531 		    continue;
532 	    overlap = min(pch, svalue1) - max(pcl, svalue0);
533 	    if (overlap > 0) {
534 #		ifdef DEBUG
535 		    if (debug & SAMPLEDEBUG) {
536 			printf("[asgnsamples] (0x%lx->0x%lx-0x%lx) %s gets %f ticks %lu overlap\n",
537 				nl[j].value / HISTORICAL_SCALE_2,
538 				svalue0, svalue1, nl[j].name,
539 				overlap * thetime / scale, overlap);
540 		    }
541 #		endif /* DEBUG */
542 		nl[j].time += overlap * thetime / scale;
543 	    }
544 	}
545     }
546 #   ifdef DEBUG
547 	if (debug & SAMPLEDEBUG) {
548 	    printf("[asgnsamples] totime %f\n", totime);
549 	}
550 #   endif /* DEBUG */
551 }
552 
553 
554 unsigned long
555 min(unsigned long a, unsigned long b)
556 {
557     if (a<b)
558 	return(a);
559     return(b);
560 }
561 
562 unsigned long
563 max(unsigned long a, unsigned long b)
564 {
565     if (a>b)
566 	return(a);
567     return(b);
568 }
569 
570     /*
571      *	calculate scaled entry point addresses (to save time in asgnsamples),
572      *	and possibly push the scaled entry points over the entry mask,
573      *	if it turns out that the entry point is in one bucket and the code
574      *	for a routine is in the next bucket.
575      */
576 void
577 alignentries(void)
578 {
579     register struct nl	*nlp;
580     unsigned long	bucket_of_entry;
581     unsigned long	bucket_of_code;
582 
583     for (nlp = nl; nlp < npe; nlp++) {
584 	nlp -> svalue = nlp -> value / HISTORICAL_SCALE_2;
585 	bucket_of_entry = (nlp->svalue - lowpc) / scale;
586 	bucket_of_code = (nlp->svalue + OFFSET_OF_CODE / HISTORICAL_SCALE_2 -
587 	  lowpc) / scale;
588 	if (bucket_of_entry < bucket_of_code) {
589 #	    ifdef DEBUG
590 		if (debug & SAMPLEDEBUG) {
591 		    printf("[alignentries] pushing svalue 0x%lx to 0x%lx\n",
592 			    nlp->svalue,
593 			    nlp->svalue + OFFSET_OF_CODE / HISTORICAL_SCALE_2);
594 		}
595 #	    endif /* DEBUG */
596 	    nlp->svalue += OFFSET_OF_CODE / HISTORICAL_SCALE_2;
597 	}
598     }
599 }
600