1/* basic_blocks.c  -  Basic-block level related code: reading/writing
2   of basic-block info to/from gmon.out; computing and formatting of
3   basic-block related statistics.
4
5   Copyright (C) 1999-2017 Free Software Foundation, Inc.
6
7   This file is part of GNU Binutils.
8
9   This program is free software; you can redistribute it and/or modify
10   it under the terms of the GNU General Public License as published by
11   the Free Software Foundation; either version 3 of the License, or
12   (at your option) any later version.
13
14   This program is distributed in the hope that it will be useful,
15   but WITHOUT ANY WARRANTY; without even the implied warranty of
16   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17   GNU General Public License for more details.
18
19   You should have received a copy of the GNU General Public License
20   along with this program; if not, write to the Free Software
21   Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA
22   02110-1301, USA.  */
23
24#include "gprof.h"
25#include "libiberty.h"
26#include "filenames.h"
27#include "basic_blocks.h"
28#include "corefile.h"
29#include "gmon_io.h"
30#include "gmon_out.h"
31#include "search_list.h"
32#include "source.h"
33#include "symtab.h"
34#include "sym_ids.h"
35
36static int cmp_bb (const PTR, const PTR);
37static int cmp_ncalls (const PTR, const PTR);
38static void fskip_string (FILE *);
39static void annotate_with_count (char *, unsigned int, int, PTR);
40
41/* Default option values:  */
42bfd_boolean bb_annotate_all_lines = FALSE;
43unsigned long bb_min_calls = 1;
44int bb_table_length = 10;
45
46/* Variables used to compute annotated source listing stats:  */
47static long num_executable_lines;
48static long num_lines_executed;
49
50
51/* Helper for sorting.  Compares two symbols and returns result
52   such that sorting will be increasing according to filename, line
53   number, and address (in that order).  */
54
55static int
56cmp_bb (const PTR lp, const PTR rp)
57{
58  int r;
59  const Sym *left = *(const Sym **) lp;
60  const Sym *right = *(const Sym **) rp;
61
62  if (left->file && right->file)
63    {
64      r = filename_cmp (left->file->name, right->file->name);
65
66      if (r)
67	return r;
68
69      if (left->line_num != right->line_num)
70	return left->line_num - right->line_num;
71    }
72
73  if (left->addr < right->addr)
74    return -1;
75  else if (left->addr > right->addr)
76    return 1;
77  else
78    return 0;
79}
80
81
82/* Helper for sorting.  Order basic blocks in decreasing number of
83   calls, ties are broken in increasing order of line numbers.  */
84static int
85cmp_ncalls (const PTR lp, const PTR rp)
86{
87  const Sym *left = *(const Sym **) lp;
88  const Sym *right = *(const Sym **) rp;
89
90  if (!left)
91    return 1;
92  else if (!right)
93    return -1;
94
95  if (left->ncalls < right->ncalls)
96    return 1;
97  else if (left->ncalls > right->ncalls)
98    return -1;
99
100  return left->line_num - right->line_num;
101}
102
103/* Skip over variable length string.  */
104static void
105fskip_string (FILE *fp)
106{
107  int ch;
108
109  while ((ch = fgetc (fp)) != EOF)
110    {
111      if (ch == '\0')
112	break;
113    }
114}
115
116/* Read a basic-block record from file IFP.  FILENAME is the name
117   of file IFP and is provided for formatting error-messages only.  */
118
119void
120bb_read_rec (FILE *ifp, const char *filename)
121{
122  unsigned int nblocks, b;
123  bfd_vma addr, ncalls;
124  Sym *sym;
125
126  if (gmon_io_read_32 (ifp, &nblocks))
127    {
128      fprintf (stderr, _("%s: %s: unexpected end of file\n"),
129	       whoami, filename);
130      done (1);
131    }
132
133  nblocks = bfd_get_32 (core_bfd, (bfd_byte *) & nblocks);
134  if (gmon_file_version == 0)
135    fskip_string (ifp);
136
137  for (b = 0; b < nblocks; ++b)
138    {
139      if (gmon_file_version == 0)
140	{
141	  int line_num;
142
143	  /* Version 0 had lots of extra stuff that we don't
144	     care about anymore.  */
145	  if ((fread (&ncalls, sizeof (ncalls), 1, ifp) != 1)
146	      || (fread (&addr, sizeof (addr), 1, ifp) != 1)
147	      || (fskip_string (ifp), FALSE)
148	      || (fskip_string (ifp), FALSE)
149	      || (fread (&line_num, sizeof (line_num), 1, ifp) != 1))
150	    {
151	      perror (filename);
152	      done (1);
153	    }
154	}
155      else if (gmon_io_read_vma (ifp, &addr)
156	       || gmon_io_read_vma (ifp, &ncalls))
157	{
158	  perror (filename);
159	  done (1);
160	}
161
162      /* Basic-block execution counts are meaningful only if we're
163	 profiling at the line-by-line level:  */
164      if (line_granularity)
165	{
166	  sym = sym_lookup (&symtab, addr);
167
168	  if (sym)
169	    {
170	      int i;
171
172	      DBG (BBDEBUG,
173		   printf ("[bb_read_rec] 0x%lx->0x%lx (%s:%d) cnt=%lu\n",
174			   (unsigned long) addr, (unsigned long) sym->addr,
175			   sym->name, sym->line_num, (unsigned long) ncalls));
176
177	      for (i = 0; i < NBBS; i++)
178		{
179		  if (! sym->bb_addr[i] || sym->bb_addr[i] == addr)
180		    {
181		      sym->bb_addr[i] = addr;
182		      sym->bb_calls[i] += ncalls;
183		      break;
184		    }
185		}
186	    }
187	}
188      else
189	{
190	  static bfd_boolean user_warned = FALSE;
191
192	  if (!user_warned)
193	    {
194	      user_warned = TRUE;
195	      fprintf (stderr,
196  _("%s: warning: ignoring basic-block exec counts (use -l or --line)\n"),
197		       whoami);
198	    }
199	}
200    }
201  return;
202}
203
204/* Write all basic-blocks with non-zero counts to file OFP.  FILENAME
205   is the name of OFP and is provided for producing error-messages
206   only.  */
207void
208bb_write_blocks (FILE *ofp, const char *filename)
209{
210  unsigned int nblocks = 0;
211  Sym *sym;
212  int i;
213
214  /* Count how many non-zero blocks with have:  */
215  for (sym = symtab.base; sym < symtab.limit; ++sym)
216    {
217      for (i = 0; i < NBBS && sym->bb_addr[i]; i++)
218	;
219      nblocks += i;
220    }
221
222  /* Write header:  */
223  if (gmon_io_write_8 (ofp, GMON_TAG_BB_COUNT)
224      || gmon_io_write_32 (ofp, nblocks))
225    {
226      perror (filename);
227      done (1);
228    }
229
230  /* Write counts:  */
231  for (sym = symtab.base; sym < symtab.limit; ++sym)
232    {
233      for (i = 0; i < NBBS && sym->bb_addr[i]; i++)
234	{
235	  if (gmon_io_write_vma (ofp, sym->bb_addr[i])
236	      || gmon_io_write_vma (ofp, (bfd_vma) sym->bb_calls[i]))
237	    {
238	      perror (filename);
239	      done (1);
240	    }
241	}
242    }
243}
244
245/* Output basic-block statistics in a format that is easily parseable.
246   Current the format is:
247
248	<filename>:<line-number>: (<function-name>:<bb-addr): <ncalls>  */
249
250void
251print_exec_counts (void)
252{
253  Sym **sorted_bbs, *sym;
254  unsigned int i, j, len;
255
256  if (first_output)
257    first_output = FALSE;
258  else
259    printf ("\f\n");
260
261  /* Sort basic-blocks according to function name and line number:  */
262  sorted_bbs = (Sym **) xmalloc (symtab.len * sizeof (sorted_bbs[0]));
263  len = 0;
264
265  for (sym = symtab.base; sym < symtab.limit; ++sym)
266    {
267      /* Accept symbol if it's in the INCL_EXEC table
268	 or there is no INCL_EXEC table
269	 and it does not appear in the EXCL_EXEC table.  */
270      if (sym_lookup (&syms[INCL_EXEC], sym->addr)
271	  || (syms[INCL_EXEC].len == 0
272	      && !sym_lookup (&syms[EXCL_EXEC], sym->addr)))
273	{
274	  sorted_bbs[len++] = sym;
275	}
276    }
277
278  qsort (sorted_bbs, len, sizeof (sorted_bbs[0]), cmp_bb);
279
280  /* Output basic-blocks:  */
281
282  for (i = 0; i < len; ++i)
283    {
284      sym = sorted_bbs [i];
285
286      if (sym->ncalls > 0 || ! ignore_zeros)
287	{
288	  /* FIXME: This only works if bfd_vma is unsigned long.  */
289	  printf (_("%s:%d: (%s:0x%lx) %lu executions\n"),
290		  sym->file ? sym->file->name : _("<unknown>"), sym->line_num,
291		  sym->name, (unsigned long) sym->addr, sym->ncalls);
292	}
293
294      for (j = 0; j < NBBS && sym->bb_addr[j]; j ++)
295	{
296	  if (sym->bb_calls[j] > 0 || ! ignore_zeros)
297	    {
298	      /* FIXME: This only works if bfd_vma is unsigned long.  */
299	      printf (_("%s:%d: (%s:0x%lx) %lu executions\n"),
300		      sym->file ? sym->file->name : _("<unknown>"), sym->line_num,
301		      sym->name, (unsigned long) sym->bb_addr[j],
302		      sym->bb_calls[j]);
303	    }
304	}
305    }
306  free (sorted_bbs);
307}
308
309/* Helper for bb_annotated_source: format annotation containing
310   number of line executions.  Depends on being called on each
311   line of a file in sequential order.
312
313   Global variable bb_annotate_all_lines enables execution count
314   compression (counts are suppressed if identical to the last one)
315   and prints counts on all executed lines.  Otherwise, print
316   all basic-block execution counts exactly once on the line
317   that starts the basic-block.  */
318
319static void
320annotate_with_count (char *buf, unsigned int width, int line_num, PTR arg)
321{
322  Source_File *sf = (Source_File *) arg;
323  Sym *b;
324  unsigned int i;
325  static unsigned long last_count;
326  unsigned long last_print = (unsigned long) -1;
327
328  b = NULL;
329
330  if (line_num <= sf->num_lines)
331    b = (Sym *) sf->line[line_num - 1];
332
333  if (!b)
334    {
335      for (i = 0; i < width; i++)
336	buf[i] = ' ';
337      buf[width] = '\0';
338    }
339  else
340    {
341      char tmpbuf[NBBS * 30];
342      char *p;
343      unsigned long ncalls;
344      int ncalls_set;
345      unsigned int len;
346
347      ++num_executable_lines;
348
349      p = tmpbuf;
350      *p = '\0';
351
352      ncalls = 0;
353      ncalls_set = 0;
354
355      /* If this is a function entry point, label the line no matter what.
356	 Otherwise, we're in the middle of a function, so check to see
357	 if the first basic-block address is larger than the starting
358	 address of the line.  If so, then this line begins with a
359	 a portion of the previous basic-block, so print that prior
360	 execution count (if bb_annotate_all_lines is set).  */
361      if (b->is_func)
362	{
363	  sprintf (p, "%lu", b->ncalls);
364	  p += strlen (p);
365	  last_count = b->ncalls;
366	  last_print = last_count;
367	  ncalls = b->ncalls;
368	  ncalls_set = 1;
369	}
370      else if (bb_annotate_all_lines
371	       && b->bb_addr[0] && b->bb_addr[0] > b->addr)
372	{
373	  sprintf (p, "%lu", last_count);
374	  p += strlen (p);
375	  last_print = last_count;
376	  ncalls = last_count;
377	  ncalls_set = 1;
378	}
379
380      /* Loop through all of this line's basic-blocks.  For each one,
381	 update last_count, then compress sequential identical counts
382	 (if bb_annotate_all_lines) and print the execution count.  */
383
384      for (i = 0; i < NBBS && b->bb_addr[i]; i++)
385	{
386	  last_count = b->bb_calls[i];
387	  if (! ncalls_set)
388	    {
389	      ncalls = 0;
390	      ncalls_set = 1;
391	    }
392	  ncalls += last_count;
393
394	  if (bb_annotate_all_lines && last_count == last_print)
395	    continue;
396
397	  if (p > tmpbuf)
398	    *p++ = ',';
399	  sprintf (p, "%lu", last_count);
400	  p += strlen (p);
401
402	  last_print = last_count;
403	}
404
405      /* We're done.  If nothing has been printed on this line,
406	 print the last execution count (bb_annotate_all_lines),
407	 which could be from either a previous line (if there were
408	 no BBs on this line), or from this line (if all our BB
409	 counts were compressed out because they were identical).  */
410
411      if (bb_annotate_all_lines && p == tmpbuf)
412	{
413	  sprintf (p, "%lu", last_count);
414	  p += strlen (p);
415	  ncalls = last_count;
416	  ncalls_set = 1;
417	}
418
419      if (! ncalls_set)
420	{
421	  unsigned int c;
422
423	  for (c = 0; c < width; c++)
424	    buf[c] = ' ';
425	  buf[width] = '\0';
426	  return;
427	}
428
429      ++num_lines_executed;
430
431      if (ncalls < bb_min_calls)
432	{
433	  strcpy (tmpbuf, "#####");
434	  p = tmpbuf + 5;
435	}
436
437      strcpy (p, " -> ");
438      p += 4;
439
440      len = p - tmpbuf;
441      if (len >= width)
442	{
443	  strncpy (buf, tmpbuf, width);
444	  buf[width] = '\0';
445	}
446      else
447	{
448	  unsigned int c;
449
450	  strcpy (buf + width - len, tmpbuf);
451	  for (c = 0; c < width - len; ++c)
452	    buf[c] = ' ';
453	}
454    }
455}
456
457/* Annotate the files named in SOURCE_FILES with basic-block statistics
458   (execution counts).  After each source files, a few statistics
459   regarding that source file are printed.  */
460
461void
462print_annotated_source (void)
463{
464  Sym *sym, *line_stats, *new_line;
465  Source_File *sf;
466  int i, table_len;
467  FILE *ofp;
468
469  /* Find maximum line number for each source file that user is
470     interested in:  */
471  for (sym = symtab.base; sym < symtab.limit; ++sym)
472    {
473      /* Accept symbol if it's file is known, its line number is
474	 bigger than anything we have seen for that file so far and
475	 if it's in the INCL_ANNO table or there is no INCL_ANNO
476	 table and it does not appear in the EXCL_ANNO table.  */
477      if (sym->file && sym->line_num > sym->file->num_lines
478	  && (sym_lookup (&syms[INCL_ANNO], sym->addr)
479	      || (syms[INCL_ANNO].len == 0
480		  && !sym_lookup (&syms[EXCL_ANNO], sym->addr))))
481	{
482	  sym->file->num_lines = sym->line_num;
483	}
484    }
485
486  /* Allocate line descriptors:  */
487  for (sf = first_src_file; sf; sf = sf->next)
488    {
489      if (sf->num_lines > 0)
490	{
491	  sf->line = (void **) xmalloc (sf->num_lines * sizeof (sf->line[0]));
492	  memset (sf->line, 0, sf->num_lines * sizeof (sf->line[0]));
493	}
494    }
495
496  /* Count executions per line:  */
497  for (sym = symtab.base; sym < symtab.limit; ++sym)
498    {
499      if (sym->file && sym->file->num_lines
500	  && (sym_lookup (&syms[INCL_ANNO], sym->addr)
501	      || (syms[INCL_ANNO].len == 0
502		  && !sym_lookup (&syms[EXCL_ANNO], sym->addr))))
503	{
504	  sym->file->ncalls += sym->ncalls;
505	  line_stats = (Sym *) sym->file->line[sym->line_num - 1];
506
507	  if (!line_stats)
508	    {
509	      /* Common case has at most one basic-block per source line:  */
510	      sym->file->line[sym->line_num - 1] = sym;
511	    }
512	  else if (!line_stats->addr)
513	    {
514	      /* sym is the 3rd .. nth basic block for this line:  */
515	      line_stats->ncalls += sym->ncalls;
516	    }
517	  else
518	    {
519	      /* sym is the second basic block for this line.  */
520	      new_line = (Sym *) xmalloc (sizeof (*new_line));
521	      *new_line = *line_stats;
522	      new_line->addr = 0;
523	      new_line->ncalls += sym->ncalls;
524	      sym->file->line[sym->line_num - 1] = new_line;
525	    }
526	}
527    }
528
529  /* Plod over source files, annotating them:  */
530  for (sf = first_src_file; sf; sf = sf->next)
531    {
532      if (!sf->num_lines || (ignore_zeros && sf->ncalls == 0))
533	continue;
534
535      num_executable_lines = num_lines_executed = 0;
536
537      ofp = annotate_source (sf, 16, annotate_with_count, sf);
538      if (!ofp)
539	continue;
540
541      if (bb_table_length > 0)
542	{
543	  fprintf (ofp, _("\n\nTop %d Lines:\n\n     Line      Count\n\n"),
544		   bb_table_length);
545
546	  /* Abuse line arrays---it's not needed anymore:  */
547	  qsort (sf->line, sf->num_lines, sizeof (sf->line[0]), cmp_ncalls);
548	  table_len = bb_table_length;
549
550	  if (table_len > sf->num_lines)
551	    table_len = sf->num_lines;
552
553	  for (i = 0; i < table_len; ++i)
554	    {
555	      sym = (Sym *) sf->line[i];
556
557	      if (!sym || sym->ncalls == 0)
558		  break;
559
560	      fprintf (ofp, "%9d %10lu\n", sym->line_num, sym->ncalls);
561	    }
562	}
563
564      free (sf->line);
565      sf->line = 0;
566
567      fprintf (ofp, _("\nExecution Summary:\n\n"));
568      fprintf (ofp, _("%9ld   Executable lines in this file\n"),
569	       num_executable_lines);
570      fprintf (ofp, _("%9ld   Lines executed\n"), num_lines_executed);
571      fprintf (ofp, _("%9.2f   Percent of the file executed\n"),
572	       num_executable_lines
573	       ? 100.0 * num_lines_executed / (double) num_executable_lines
574	       : 100.0);
575      fprintf (ofp, _("\n%9lu   Total number of line executions\n"),
576	       sf->ncalls);
577      fprintf (ofp, _("%9.2f   Average executions per line\n"),
578	       num_executable_lines
579	       ? (double) sf->ncalls / (double) num_executable_lines
580	       : 0.0);
581
582      if (ofp != stdout)
583	fclose (ofp);
584    }
585}
586