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, 2007
   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 3 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., 51 Franklin Street - Fifth Floor, Boston, MA
  23    02110-1301, USA.  */
  24 \f
  25 #include "gprof.h"
  26 #include "libiberty.h"
  27 #include "filenames.h"
  28 #include "basic_blocks.h"
  29 #include "corefile.h"
  30 #include "gmon_io.h"
  31 #include "gmon_out.h"
  32 #include "search_list.h"
  33 #include "source.h"
  34 #include "symtab.h"
  35 #include "sym_ids.h"
  36
  37 static int cmp_bb (const PTR, const PTR);
  38 static int cmp_ncalls (const PTR, const PTR);
  39 static void fskip_string (FILE *);
  40 static void annotate_with_count (char *, unsigned int, int, PTR);
  41
  42 /* Default option values:  */
  43 bfd_boolean bb_annotate_all_lines = FALSE;
  44 unsigned long bb_min_calls = 1;
  45 int bb_table_length = 10;
  46
  47 /* Variables used to compute annotated source listing stats:  */
  48 static long num_executable_lines;
  49 static long num_lines_executed;
  50
  51
  52 /* Helper for sorting.  Compares two symbols and returns result
  53    such that sorting will be increasing according to filename, line
  54    number, and address (in that order).  */
  55
  56 static int
  57 cmp_bb (const PTR lp, const PTR rp)
  58 {
  59   int r;
  60   const Sym *left = *(const Sym **) lp;
  61   const Sym *right = *(const Sym **) rp;
  62
  63   if (left->file && right->file)
  64     {
  65       r = filename_cmp (left->file->name, right->file->name);
  66
  67       if (r)
  68         return r;
  69
  70       if (left->line_num != right->line_num)
  71         return left->line_num - right->line_num;
  72     }
  73
  74   if (left->addr < right->addr)
  75     return -1;
  76   else if (left->addr > right->addr)
  77     return 1;
  78   else
  79     return 0;
  80 }
  81
  82
  83 /* Helper for sorting.  Order basic blocks in decreasing number of
  84    calls, ties are broken in increasing order of line numbers.  */
  85 static int
  86 cmp_ncalls (const PTR lp, const PTR rp)
  87 {
  88   const Sym *left = *(const Sym **) lp;
  89   const Sym *right = *(const Sym **) rp;
  90
  91   if (!left)
  92     return 1;
  93   else if (!right)
  94     return -1;
  95
  96   if (left->ncalls < right->ncalls)
  97     return 1;
  98   else if (left->ncalls > right->ncalls)
  99     return -1;
 100
 101   return left->line_num - right->line_num;
 102 }
 103
 104 /* Skip over variable length string.  */
 105 static void
 106 fskip_string (FILE *fp)
 107 {
 108   int ch;
 109
 110   while ((ch = fgetc (fp)) != EOF)
 111     {
 112       if (ch == '\0')
 113         break;
 114     }
 115 }
 116
 117 /* Read a basic-block record from file IFP.  FILENAME is the name
 118    of file IFP and is provided for formatting error-messages only.  */
 119
 120 void
 121 bb_read_rec (FILE *ifp, const char *filename)
 122 {
 123   unsigned int nblocks, b;
 124   bfd_vma addr, ncalls;
 125   Sym *sym;
 126
 127   if (gmon_io_read_32 (ifp, &nblocks))
 128     {
 129       fprintf (stderr, _("%s: %s: unexpected end of file\n"),
 130                whoami, filename);
 131       done (1);
 132     }
 133
 134   nblocks = bfd_get_32 (core_bfd, (bfd_byte *) & nblocks);
 135   if (gmon_file_version == 0)
 136     fskip_string (ifp);
 137
 138   for (b = 0; b < nblocks; ++b)
 139     {
 140       if (gmon_file_version == 0)
 141         {
 142           int line_num;
 143
 144           /* Version 0 had lots of extra stuff that we don't
 145              care about anymore.  */
 146           if ((fread (&ncalls, sizeof (ncalls), 1, ifp) != 1)
 147               || (fread (&addr, sizeof (addr), 1, ifp) != 1)
 148               || (fskip_string (ifp), FALSE)
 149               || (fskip_string (ifp), FALSE)
 150               || (fread (&line_num, sizeof (line_num), 1, ifp) != 1))
 151             {
 152               perror (filename);
 153               done (1);
 154             }
 155         }
 156       else if (gmon_io_read_vma (ifp, &addr)
 157                || gmon_io_read_vma (ifp, &ncalls))
 158         {
 159           perror (filename);
 160           done (1);
 161         }
 162
 163       /* Basic-block execution counts are meaningful only if we're
 164          profiling at the line-by-line level:  */
 165       if (line_granularity)
 166         {
 167           sym = sym_lookup (&symtab, addr);
 168
 169           if (sym)
 170             {
 171               int i;
 172
 173               DBG (BBDEBUG,
 174                    printf ("[bb_read_rec] 0x%lx->0x%lx (%s:%d) cnt=%lu\n",
 175                            (unsigned long) addr, (unsigned long) sym->addr,
 176                            sym->name, sym->line_num, (unsigned long) ncalls));
 177
 178               for (i = 0; i < NBBS; i++)
 179                 {
 180                   if (! sym->bb_addr[i] || sym->bb_addr[i] == addr)
 181                     {
 182                       sym->bb_addr[i] = addr;
 183                       sym->bb_calls[i] += ncalls;
 184                       break;
 185                     }
 186                 }
 187             }
 188         }
 189       else
 190         {
 191           static bfd_boolean user_warned = FALSE;
 192
 193           if (!user_warned)
 194             {
 195               user_warned = TRUE;
 196               fprintf (stderr,
 197   _("%s: warning: ignoring basic-block exec counts (use -l or --line)\n"),
 198                        whoami);
 199             }
 200         }
 201     }
 202   return;
 203 }
 204
 205 /* Write all basic-blocks with non-zero counts to file OFP.  FILENAME
 206    is the name of OFP and is provided for producing error-messages
 207    only.  */
 208 void
 209 bb_write_blocks (FILE *ofp, const char *filename)
 210 {
 211   unsigned int nblocks = 0;
 212   Sym *sym;
 213   int i;
 214
 215   /* Count how many non-zero blocks with have:  */
 216   for (sym = symtab.base; sym < symtab.limit; ++sym)
 217     {
 218       for (i = 0; i < NBBS && sym->bb_addr[i]; i++)
 219         ;
 220       nblocks += i;
 221     }
 222
 223   /* Write header:  */
 224   if (gmon_io_write_8 (ofp, GMON_TAG_BB_COUNT)
 225       || gmon_io_write_32 (ofp, nblocks))
 226     {
 227       perror (filename);
 228       done (1);
 229     }
 230
 231   /* Write counts:  */
 232   for (sym = symtab.base; sym < symtab.limit; ++sym)
 233     {
 234       for (i = 0; i < NBBS && sym->bb_addr[i]; i++)
 235         {
 236           if (gmon_io_write_vma (ofp, sym->bb_addr[i])
 237               || gmon_io_write_vma (ofp, (bfd_vma) sym->bb_calls[i]))
 238             {
 239               perror (filename);
 240               done (1);
 241             }
 242         }
 243     }
 244 }
 245
 246 /* Output basic-block statistics in a format that is easily parseable.
 247    Current the format is:
 248
 249         <filename>:<line-number>: (<function-name>:<bb-addr): <ncalls>  */
 250
 251 void
 252 print_exec_counts ()
 253 {
 254   Sym **sorted_bbs, *sym;
 255   unsigned int i, j, len;
 256
 257   if (first_output)
 258     first_output = FALSE;
 259   else
 260     printf ("\f\n");
 261
 262   /* Sort basic-blocks according to function name and line number:  */
 263   sorted_bbs = (Sym **) xmalloc (symtab.len * sizeof (sorted_bbs[0]));
 264   len = 0;
 265
 266   for (sym = symtab.base; sym < symtab.limit; ++sym)
 267     {
 268       /* Accept symbol if it's in the INCL_EXEC table
 269          or there is no INCL_EXEC table
 270          and it does not appear in the EXCL_EXEC table.  */
 271       if (sym_lookup (&syms[INCL_EXEC], sym->addr)
 272           || (syms[INCL_EXEC].len == 0
 273               && !sym_lookup (&syms[EXCL_EXEC], sym->addr)))
 274         {
 275           sorted_bbs[len++] = sym;
 276         }
 277     }
 278
 279   qsort (sorted_bbs, len, sizeof (sorted_bbs[0]), cmp_bb);
 280
 281   /* Output basic-blocks:  */
 282
 283   for (i = 0; i < len; ++i)
 284     {
 285       sym = sorted_bbs [i];
 286
 287       if (sym->ncalls > 0 || ! ignore_zeros)
 288         {
 289           /* FIXME: This only works if bfd_vma is unsigned long.  */
 290           printf (_("%s:%d: (%s:0x%lx) %lu executions\n"),
 291                   sym->file ? sym->file->name : _("<unknown>"), sym->line_num,
 292                   sym->name, (unsigned long) sym->addr, sym->ncalls);
 293         }
 294
 295       for (j = 0; j < NBBS && sym->bb_addr[j]; j ++)
 296         {
 297           if (sym->bb_calls[j] > 0 || ! ignore_zeros)
 298             {
 299               /* FIXME: This only works if bfd_vma is unsigned long.  */
 300               printf (_("%s:%d: (%s:0x%lx) %lu executions\n"),
 301                       sym->file ? sym->file->name : _("<unknown>"), sym->line_num,
 302                       sym->name, (unsigned long) sym->bb_addr[j],
 303                       sym->bb_calls[j]);
 304             }
 305         }
 306     }
 307   free (sorted_bbs);
 308 }
 309
 310 /* Helper for bb_annotated_source: format annotation containing
 311    number of line executions.  Depends on being called on each
 312    line of a file in sequential order.
 313
 314    Global variable bb_annotate_all_lines enables execution count
 315    compression (counts are supressed if identical to the last one)
 316    and prints counts on all executed lines.  Otherwise, print
 317    all basic-block execution counts exactly once on the line
 318    that starts the basic-block.  */
 319
 320 static void
 321 annotate_with_count (char *buf, unsigned int width, int line_num, PTR arg)
 322 {
 323   Source_File *sf = (Source_File *) arg;
 324   Sym *b;
 325   unsigned int i;
 326   static unsigned long last_count;
 327   unsigned long last_print = (unsigned long) -1;
 328
 329   b = NULL;
 330
 331   if (line_num <= sf->num_lines)
 332     b = (Sym *) sf->line[line_num - 1];
 333
 334   if (!b)
 335     {
 336       for (i = 0; i < width; i++)
 337         buf[i] = ' ';
 338       buf[width] = '\0';
 339     }
 340   else
 341     {
 342       char tmpbuf[NBBS * 30];
 343       char *p;
 344       unsigned long ncalls;
 345       int ncalls_set;
 346       unsigned int len;
 347
 348       ++num_executable_lines;
 349
 350       p = tmpbuf;
 351       *p = '\0';
 352
 353       ncalls = 0;
 354       ncalls_set = 0;
 355
 356       /* If this is a function entry point, label the line no matter what.
 357          Otherwise, we're in the middle of a function, so check to see
 358          if the first basic-block address is larger than the starting
 359          address of the line.  If so, then this line begins with a
 360          a portion of the previous basic-block, so print that prior
 361          execution count (if bb_annotate_all_lines is set).  */
 362       if (b->is_func)
 363         {
 364           sprintf (p, "%lu", b->ncalls);
 365           p += strlen (p);
 366           last_count = b->ncalls;
 367           last_print = last_count;
 368           ncalls = b->ncalls;
 369           ncalls_set = 1;
 370         }
 371       else if (bb_annotate_all_lines
 372                && b->bb_addr[0] && b->bb_addr[0] > b->addr)
 373         {
 374           sprintf (p, "%lu", last_count);
 375           p += strlen (p);
 376           last_print = last_count;
 377           ncalls = last_count;
 378           ncalls_set = 1;
 379         }
 380
 381       /* Loop through all of this line's basic-blocks.  For each one,
 382          update last_count, then compress sequential identical counts
 383          (if bb_annotate_all_lines) and print the execution count.  */
 384
 385       for (i = 0; i < NBBS && b->bb_addr[i]; i++)
 386         {
 387           last_count = b->bb_calls[i];
 388           if (! ncalls_set)
 389             {
 390               ncalls = 0;
 391               ncalls_set = 1;
 392             }
 393           ncalls += last_count;
 394
 395           if (bb_annotate_all_lines && last_count == last_print)
 396             continue;
 397
 398           if (p > tmpbuf)
 399             *p++ = ',';
 400           sprintf (p, "%lu", last_count);
 401           p += strlen (p);
 402
 403           last_print = last_count;
 404         }
 405
 406       /* We're done.  If nothing has been printed on this line,
 407          print the last execution count (bb_annotate_all_lines),
 408          which could be from either a previous line (if there were
 409          no BBs on this line), or from this line (if all our BB
 410          counts were compressed out because they were identical).  */
 411
 412       if (bb_annotate_all_lines && p == tmpbuf)
 413         {
 414           sprintf (p, "%lu", last_count);
 415           p += strlen (p);
 416           ncalls = last_count;
 417           ncalls_set = 1;
 418         }
 419
 420       if (! ncalls_set)
 421         {
 422           unsigned int c;
 423
 424           for (c = 0; c < width; c++)
 425             buf[c] = ' ';
 426           buf[width] = '\0';
 427           return;
 428         }
 429
 430       ++num_lines_executed;
 431
 432       if (ncalls < bb_min_calls)
 433         {
 434           strcpy (tmpbuf, "#####");
 435           p = tmpbuf + 5;
 436         }
 437
 438       strcpy (p, " -> ");
 439       p += 4;
 440
 441       len = p - tmpbuf;
 442       if (len >= width)
 443         {
 444           strncpy (buf, tmpbuf, width);
 445           buf[width] = '\0';
 446         }
 447       else
 448         {
 449           unsigned int c;
 450
 451           strcpy (buf + width - len, tmpbuf);
 452           for (c = 0; c < width - len; ++c)
 453             buf[c] = ' ';
 454         }
 455     }
 456 }
 457
 458 /* Annotate the files named in SOURCE_FILES with basic-block statistics
 459    (execution counts).  After each source files, a few statistics
 460    regarding that source file are printed.  */
 461
 462 void
 463 print_annotated_source ()
 464 {
 465   Sym *sym, *line_stats, *new_line;
 466   Source_File *sf;
 467   int i, table_len;
 468   FILE *ofp;
 469
 470   /* Find maximum line number for each source file that user is
 471      interested in:  */
 472   for (sym = symtab.base; sym < symtab.limit; ++sym)
 473     {
 474       /* Accept symbol if it's file is known, its line number is
 475          bigger than anything we have seen for that file so far and
 476          if it's in the INCL_ANNO table or there is no INCL_ANNO
 477          table and it does not appear in the EXCL_ANNO table.  */
 478       if (sym->file && sym->line_num > sym->file->num_lines
 479           && (sym_lookup (&syms[INCL_ANNO], sym->addr)
 480               || (syms[INCL_ANNO].len == 0
 481                   && !sym_lookup (&syms[EXCL_ANNO], sym->addr))))
 482         {
 483           sym->file->num_lines = sym->line_num;
 484         }
 485     }
 486
 487   /* Allocate line descriptors:  */
 488   for (sf = first_src_file; sf; sf = sf->next)
 489     {
 490       if (sf->num_lines > 0)
 491         {
 492           sf->line = (void **) xmalloc (sf->num_lines * sizeof (sf->line[0]));
 493           memset (sf->line, 0, sf->num_lines * sizeof (sf->line[0]));
 494         }
 495     }
 496
 497   /* Count executions per line:  */
 498   for (sym = symtab.base; sym < symtab.limit; ++sym)
 499     {
 500       if (sym->file && sym->file->num_lines
 501           && (sym_lookup (&syms[INCL_ANNO], sym->addr)
 502               || (syms[INCL_ANNO].len == 0
 503                   && !sym_lookup (&syms[EXCL_ANNO], sym->addr))))
 504         {
 505           sym->file->ncalls += sym->ncalls;
 506           line_stats = (Sym *) sym->file->line[sym->line_num - 1];
 507
 508           if (!line_stats)
 509             {
 510               /* Common case has at most one basic-block per source line:  */
 511               sym->file->line[sym->line_num - 1] = sym;
 512             }
 513           else if (!line_stats->addr)
 514             {
 515               /* sym is the 3rd .. nth basic block for this line:  */
 516               line_stats->ncalls += sym->ncalls;
 517             }
 518           else
 519             {
 520               /* sym is the second basic block for this line.  */
 521               new_line = (Sym *) xmalloc (sizeof (*new_line));
 522               *new_line = *line_stats;
 523               new_line->addr = 0;
 524               new_line->ncalls += sym->ncalls;
 525               sym->file->line[sym->line_num - 1] = new_line;
 526             }
 527         }
 528     }
 529
 530   /* Plod over source files, annotating them:  */
 531   for (sf = first_src_file; sf; sf = sf->next)
 532     {
 533       if (!sf->num_lines || (ignore_zeros && sf->ncalls == 0))
 534         continue;
 535
 536       num_executable_lines = num_lines_executed = 0;
 537
 538       ofp = annotate_source (sf, 16, annotate_with_count, sf);
 539       if (!ofp)
 540         continue;
 541
 542       if (bb_table_length > 0)
 543         {
 544           fprintf (ofp, _("\n\nTop %d Lines:\n\n     Line      Count\n\n"),
 545                    bb_table_length);
 546
 547           /* Abuse line arrays---it's not needed anymore:  */
 548           qsort (sf->line, sf->num_lines, sizeof (sf->line[0]), cmp_ncalls);
 549           table_len = bb_table_length;
 550
 551           if (table_len > sf->num_lines)
 552             table_len = sf->num_lines;
 553
 554           for (i = 0; i < table_len; ++i)
 555             {
 556               sym = (Sym *) sf->line[i];
 557
 558               if (!sym || sym->ncalls == 0)
 559                   break;
 560
 561               fprintf (ofp, "%9d %10lu\n", sym->line_num, sym->ncalls);
 562             }
 563         }
 564
 565       free (sf->line);
 566       sf->line = 0;
 567
 568       fprintf (ofp, _("\nExecution Summary:\n\n"));
 569       fprintf (ofp, _("%9ld   Executable lines in this file\n"),
 570                num_executable_lines);
 571       fprintf (ofp, _("%9ld   Lines executed\n"), num_lines_executed);
 572       fprintf (ofp, _("%9.2f   Percent of the file executed\n"),
 573                num_executable_lines
 574                ? 100.0 * num_lines_executed / (double) num_executable_lines
 575                : 100.0);
 576       fprintf (ofp, _("\n%9lu   Total number of line executions\n"),
 577                sf->ncalls);
 578       fprintf (ofp, _("%9.2f   Average executions per line\n"),
 579                num_executable_lines
 580                ? (double) sf->ncalls / (double) num_executable_lines
 581                : 0.0);
 582
 583       if (ofp != stdout)
 584         fclose (ofp);
 585     }
 586 }