gprof/basic_blocks.c

   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 1999, 2000, 2001, 2002, 2004, 2005
   6    Free Software Foundation, Inc.
   7
   8    This file is part of GNU Binutils.
   9
  10    This program is free software; you can redistribute it and/or modify
  11    it under the terms of the GNU General Public License as published by
  12    the Free Software Foundation; either version 2 of the License, or
  13    (at your option) any later version.
  14
  15    This program is distributed in the hope that it will be useful,
  16    but WITHOUT ANY WARRANTY; without even the implied warranty of
  17    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18    GNU General Public License for more details.
  19
  20    You should have received a copy of the GNU General Public License
  21    along with this program; if not, write to the Free Software
  22    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  23    02111-1307, USA.  */
  24 \f
  25 #include "libiberty.h"
  26 #include "gprof.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
  36 static int cmp_bb (const PTR, const PTR);
  37 static int cmp_ncalls (const PTR, const PTR);
  38 static void fskip_string (FILE *);
  39 static void annotate_with_count (char *, unsigned int, int, PTR);
  40
  41 /* Default option values:  */
  42 bfd_boolean bb_annotate_all_lines = FALSE;
  43 unsigned long bb_min_calls = 1;
  44 int bb_table_length = 10;
  45
  46 /* Variables used to compute annotated source listing stats:  */
  47 static long num_executable_lines;
  48 static 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
  55 static int
  56 cmp_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 = strcmp (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.  */
  84 static int
  85 cmp_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.  */
 104 static void
 105 fskip_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
 119 void
 120 bb_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.  */
 207 void
 208 bb_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
 250 void
 251 print_exec_counts ()
 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       if (sym->ncalls > 0 || ! ignore_zeros)
 285         {
 286           /* FIXME: This only works if bfd_vma is unsigned long.  */
 287           printf (_("%s:%d: (%s:0x%lx) %lu executions\n"),
 288                   sym->file ? sym->file->name : _("<unknown>"), sym->line_num,
 289                   sym->name, (unsigned long) sym->addr, sym->ncalls);
 290         }
 291
 292       for (j = 0; j < NBBS && sym->bb_addr[j]; j ++)
 293         {
 294           if (sym->bb_calls[j] > 0 || ! ignore_zeros)
 295             {
 296               /* FIXME: This only works if bfd_vma is unsigned long.  */
 297               printf (_("%s:%d: (%s:0x%lx) %lu executions\n"),
 298                       sym->file ? sym->file->name : _("<unknown>"), sym->line_num,
 299                       sym->name, (unsigned long) sym->bb_addr[j],
 300                       sym->bb_calls[j]);
 301             }
 302         }
 303     }
 304   free (sorted_bbs);
 305 }
 306
 307 /* Helper for bb_annotated_source: format annotation containing
 308    number of line executions.  Depends on being called on each
 309    line of a file in sequential order.
 310
 311    Global variable bb_annotate_all_lines enables execution count
 312    compression (counts are supressed if identical to the last one)
 313    and prints counts on all executed lines.  Otherwise, print
 314    all basic-block execution counts exactly once on the line
 315    that starts the basic-block.  */
 316
 317 static void
 318 annotate_with_count (char *buf, unsigned int width, int line_num, PTR arg)
 319 {
 320   Source_File *sf = arg;
 321   Sym *b;
 322   unsigned int i;
 323   static unsigned long last_count;
 324   unsigned long last_print = (unsigned long) -1;
 325
 326   b = NULL;
 327
 328   if (line_num <= sf->num_lines)
 329     b = sf->line[line_num - 1];
 330
 331   if (!b)
 332     {
 333       for (i = 0; i < width; i++)
 334         buf[i] = ' ';
 335       buf[width] = '\0';
 336     }
 337   else
 338     {
 339       char tmpbuf[NBBS * 30];
 340       char *p;
 341       unsigned long ncalls;
 342       int ncalls_set;
 343       unsigned int len;
 344
 345       ++num_executable_lines;
 346
 347       p = tmpbuf;
 348       *p = '\0';
 349
 350       ncalls = 0;
 351       ncalls_set = 0;
 352
 353       /* If this is a function entry point, label the line no matter what.
 354          Otherwise, we're in the middle of a function, so check to see
 355          if the first basic-block address is larger than the starting
 356          address of the line.  If so, then this line begins with a
 357          a portion of the previous basic-block, so print that prior
 358          execution count (if bb_annotate_all_lines is set).  */
 359       if (b->is_func)
 360         {
 361           sprintf (p, "%lu", b->ncalls);
 362           p += strlen (p);
 363           last_count = b->ncalls;
 364           last_print = last_count;
 365           ncalls = b->ncalls;
 366           ncalls_set = 1;
 367         }
 368       else if (bb_annotate_all_lines
 369                && b->bb_addr[0] && b->bb_addr[0] > b->addr)
 370         {
 371           sprintf (p, "%lu", last_count);
 372           p += strlen (p);
 373           last_print = last_count;
 374           ncalls = last_count;
 375           ncalls_set = 1;
 376         }
 377
 378       /* Loop through all of this line's basic-blocks.  For each one,
 379          update last_count, then compress sequential identical counts
 380          (if bb_annotate_all_lines) and print the execution count.  */
 381
 382       for (i = 0; i < NBBS && b->bb_addr[i]; i++)
 383         {
 384           last_count = b->bb_calls[i];
 385           if (! ncalls_set)
 386             {
 387               ncalls = 0;
 388               ncalls_set = 1;
 389             }
 390           ncalls += last_count;
 391
 392           if (bb_annotate_all_lines && last_count == last_print)
 393             continue;
 394
 395           if (p > tmpbuf)
 396             *p++ = ',';
 397           sprintf (p, "%lu", last_count);
 398           p += strlen (p);
 399
 400           last_print = last_count;
 401         }
 402
 403       /* We're done.  If nothing has been printed on this line,
 404          print the last execution count (bb_annotate_all_lines),
 405          which could be from either a previous line (if there were
 406          no BBs on this line), or from this line (if all our BB
 407          counts were compressed out because they were identical).  */
 408
 409       if (bb_annotate_all_lines && p == tmpbuf)
 410         {
 411           sprintf (p, "%lu", last_count);
 412           p += strlen (p);
 413           ncalls = last_count;
 414           ncalls_set = 1;
 415         }
 416
 417       if (! ncalls_set)
 418         {
 419           unsigned int c;
 420
 421           for (c = 0; c < width; c++)
 422             buf[c] = ' ';
 423           buf[width] = '\0';
 424           return;
 425         }
 426
 427       ++num_lines_executed;
 428
 429       if (ncalls < bb_min_calls)
 430         {
 431           strcpy (tmpbuf, "#####");
 432           p = tmpbuf + 5;
 433         }
 434
 435       strcpy (p, " -> ");
 436       p += 4;
 437
 438       len = p - tmpbuf;
 439       if (len >= width)
 440         {
 441           strncpy (buf, tmpbuf, width);
 442           buf[width] = '\0';
 443         }
 444       else
 445         {
 446           unsigned int c;
 447
 448           strcpy (buf + width - len, tmpbuf);
 449           for (c = 0; c < width - len; ++c)
 450             buf[c] = ' ';
 451         }
 452     }
 453 }
 454
 455 /* Annotate the files named in SOURCE_FILES with basic-block statistics
 456    (execution counts).  After each source files, a few statistics
 457    regarding that source file are printed.  */
 458
 459 void
 460 print_annotated_source ()
 461 {
 462   Sym *sym, *line_stats, *new_line;
 463   Source_File *sf;
 464   int i, table_len;
 465   FILE *ofp;
 466
 467   /* Find maximum line number for each source file that user is
 468      interested in:  */
 469   for (sym = symtab.base; sym < symtab.limit; ++sym)
 470     {
 471       /* Accept symbol if it's file is known, its line number is
 472          bigger than anything we have seen for that file so far and
 473          if it's in the INCL_ANNO table or there is no INCL_ANNO
 474          table and it does not appear in the EXCL_ANNO table.  */
 475       if (sym->file && sym->line_num > sym->file->num_lines
 476           && (sym_lookup (&syms[INCL_ANNO], sym->addr)
 477               || (syms[INCL_ANNO].len == 0
 478                   && !sym_lookup (&syms[EXCL_ANNO], sym->addr))))
 479         {
 480           sym->file->num_lines = sym->line_num;
 481         }
 482     }
 483
 484   /* Allocate line descriptors:  */
 485   for (sf = first_src_file; sf; sf = sf->next)
 486     {
 487       if (sf->num_lines > 0)
 488         {
 489           sf->line = (void *) xmalloc (sf->num_lines * sizeof (sf->line[0]));
 490           memset (sf->line, 0, sf->num_lines * sizeof (sf->line[0]));
 491         }
 492     }
 493
 494   /* Count executions per line:  */
 495   for (sym = symtab.base; sym < symtab.limit; ++sym)
 496     {
 497       if (sym->file && sym->file->num_lines
 498           && (sym_lookup (&syms[INCL_ANNO], sym->addr)
 499               || (syms[INCL_ANNO].len == 0
 500                   && !sym_lookup (&syms[EXCL_ANNO], sym->addr))))
 501         {
 502           sym->file->ncalls += sym->ncalls;
 503           line_stats = sym->file->line[sym->line_num - 1];
 504
 505           if (!line_stats)
 506             {
 507               /* Common case has at most one basic-block per source line:  */
 508               sym->file->line[sym->line_num - 1] = sym;
 509             }
 510           else if (!line_stats->addr)
 511             {
 512               /* sym is the 3rd .. nth basic block for this line:  */
 513               line_stats->ncalls += sym->ncalls;
 514             }
 515           else
 516             {
 517               /* sym is the second basic block for this line.  */
 518               new_line = (Sym *) xmalloc (sizeof (*new_line));
 519               *new_line = *line_stats;
 520               new_line->addr = 0;
 521               new_line->ncalls += sym->ncalls;
 522               sym->file->line[sym->line_num - 1] = new_line;
 523             }
 524         }
 525     }
 526
 527   /* Plod over source files, annotating them:  */
 528   for (sf = first_src_file; sf; sf = sf->next)
 529     {
 530       if (!sf->num_lines || (ignore_zeros && sf->ncalls == 0))
 531         continue;
 532
 533       num_executable_lines = num_lines_executed = 0;
 534
 535       ofp = annotate_source (sf, 16, annotate_with_count, sf);
 536       if (!ofp)
 537         continue;
 538
 539       if (bb_table_length > 0)
 540         {
 541           fprintf (ofp, _("\n\nTop %d Lines:\n\n     Line      Count\n\n"),
 542                    bb_table_length);
 543
 544           /* Abuse line arrays---it's not needed anymore:  */
 545           qsort (sf->line, sf->num_lines, sizeof (sf->line[0]), cmp_ncalls);
 546           table_len = bb_table_length;
 547
 548           if (table_len > sf->num_lines)
 549             table_len = sf->num_lines;
 550
 551           for (i = 0; i < table_len; ++i)
 552             {
 553               sym = sf->line[i];
 554
 555               if (!sym || sym->ncalls == 0)
 556                   break;
 557
 558               fprintf (ofp, "%9d %10lu\n", sym->line_num, sym->ncalls);
 559             }
 560         }
 561
 562       free (sf->line);
 563       sf->line = 0;
 564
 565       fprintf (ofp, _("\nExecution Summary:\n\n"));
 566       fprintf (ofp, _("%9ld   Executable lines in this file\n"),
 567                num_executable_lines);
 568       fprintf (ofp, _("%9ld   Lines executed\n"), num_lines_executed);
 569       fprintf (ofp, _("%9.2f   Percent of the file executed\n"),
 570                num_executable_lines
 571                ? 100.0 * num_lines_executed / (double) num_executable_lines
 572                : 100.0);
 573       fprintf (ofp, _("\n%9lu   Total number of line executions\n"),
 574                sf->ncalls);
 575       fprintf (ofp, _("%9.2f   Average executions per line\n"),
 576                num_executable_lines
 577                ? (double) sf->ncalls / (double) num_executable_lines
 578                : 0.0);
 579
 580       if (ofp != stdout)
 581         fclose (ofp);
 582     }
 583 }