gcc/ipa-profile.c

   1 /* Basic IPA optimizations based on profile.
   2    Copyright (C) 2003-2014 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 /* ipa-profile pass implements the following analysis propagating profille
  21    inter-procedurally.
  22
  23    - Count histogram construction.  This is a histogram analyzing how much
  24      time is spent executing statements with a given execution count read
  25      from profile feedback. This histogram is complete only with LTO,
  26      otherwise it contains information only about the current unit.
  27
  28      Similar histogram is also estimated by coverage runtime.  This histogram
  29      is not dependent on LTO, but it suffers from various defects; first
  30      gcov runtime is not weighting individual basic block by estimated execution
  31      time and second the merging of multiple runs makes assumption that the
  32      histogram distribution did not change.  Consequentely histogram constructed
  33      here may be more precise.
  34
  35      The information is used to set hot/cold thresholds.
  36    - Next speculative indirect call resolution is performed:  the local
  37      profile pass assigns profile-id to each function and provide us with a
  38      histogram specifying the most common target.  We look up the callgraph
  39      node corresponding to the target and produce a speculative call.
  40
  41      This call may or may not survive through IPA optimization based on decision
  42      of inliner.
  43    - Finally we propagate the following flags: unlikely executed, executed
  44      once, executed at startup and executed at exit.  These flags are used to
  45      control code size/performance threshold and and code placement (by producing
  46      .text.unlikely/.text.hot/.text.startup/.text.exit subsections).  */
  47 #include "config.h"
  48 #include "system.h"
  49 #include "coretypes.h"
  50 #include "tm.h"
  51 #include "tree.h"
  52 #include "predict.h"
  53 #include "dominance.h"
  54 #include "cfg.h"
  55 #include "basic-block.h"
  56 #include "hash-map.h"
  57 #include "is-a.h"
  58 #include "plugin-api.h"
  59 #include "vec.h"
  60 #include "hashtab.h"
  61 #include "hash-set.h"
  62 #include "machmode.h"
  63 #include "hard-reg-set.h"
  64 #include "input.h"
  65 #include "function.h"
  66 #include "ipa-ref.h"
  67 #include "cgraph.h"
  68 #include "tree-pass.h"
  69 #include "tree-ssa-alias.h"
  70 #include "internal-fn.h"
  71 #include "gimple-expr.h"
  72 #include "gimple.h"
  73 #include "gimple-iterator.h"
  74 #include "flags.h"
  75 #include "target.h"
  76 #include "tree-iterator.h"
  77 #include "ipa-utils.h"
  78 #include "profile.h"
  79 #include "params.h"
  80 #include "value-prof.h"
  81 #include "alloc-pool.h"
  82 #include "tree-inline.h"
  83 #include "lto-streamer.h"
  84 #include "data-streamer.h"
  85 #include "ipa-prop.h"
  86 #include "ipa-inline.h"
  87
  88 /* Entry in the histogram.  */
  89
  90 struct histogram_entry
  91 {
  92   gcov_type count;
  93   int time;
  94   int size;
  95 };
  96
  97 /* Histogram of profile values.
  98    The histogram is represented as an ordered vector of entries allocated via
  99    histogram_pool. During construction a separate hashtable is kept to lookup
 100    duplicate entries.  */
 101
 102 vec<histogram_entry *> histogram;
 103 static alloc_pool histogram_pool;
 104
 105 /* Hashtable support for storing SSA names hashed by their SSA_NAME_VAR.  */
 106
 107 struct histogram_hash : typed_noop_remove <histogram_entry>
 108 {
 109   typedef histogram_entry value_type;
 110   typedef histogram_entry compare_type;
 111   static inline hashval_t hash (const value_type *);
 112   static inline int equal (const value_type *, const compare_type *);
 113 };
 114
 115 inline hashval_t
 116 histogram_hash::hash (const histogram_entry *val)
 117 {
 118   return val->count;
 119 }
 120
 121 inline int
 122 histogram_hash::equal (const histogram_entry *val, const histogram_entry *val2)
 123 {
 124   return val->count == val2->count;
 125 }
 126
 127 /* Account TIME and SIZE executed COUNT times into HISTOGRAM.
 128    HASHTABLE is the on-side hash kept to avoid duplicates.  */
 129
 130 static void
 131 account_time_size (hash_table<histogram_hash> *hashtable,
 132                    vec<histogram_entry *> &histogram,
 133                    gcov_type count, int time, int size)
 134 {
 135   histogram_entry key = {count, 0, 0};
 136   histogram_entry **val = hashtable->find_slot (&key, INSERT);
 137
 138   if (!*val)
 139     {
 140       *val = (histogram_entry *) pool_alloc (histogram_pool);
 141       **val = key;
 142       histogram.safe_push (*val);
 143     }
 144   (*val)->time += time;
 145   (*val)->size += size;
 146 }
 147
 148 int
 149 cmp_counts (const void *v1, const void *v2)
 150 {
 151   const histogram_entry *h1 = *(const histogram_entry * const *)v1;
 152   const histogram_entry *h2 = *(const histogram_entry * const *)v2;
 153   if (h1->count < h2->count)
 154     return 1;
 155   if (h1->count > h2->count)
 156     return -1;
 157   return 0;
 158 }
 159
 160 /* Dump HISTOGRAM to FILE.  */
 161
 162 static void
 163 dump_histogram (FILE *file, vec<histogram_entry *> histogram)
 164 {
 165   unsigned int i;
 166   gcov_type overall_time = 0, cumulated_time = 0, cumulated_size = 0, overall_size = 0;
 167
 168   fprintf (dump_file, "Histogram:\n");
 169   for (i = 0; i < histogram.length (); i++)
 170     {
 171       overall_time += histogram[i]->count * histogram[i]->time;
 172       overall_size += histogram[i]->size;
 173     }
 174   if (!overall_time)
 175     overall_time = 1;
 176   if (!overall_size)
 177     overall_size = 1;
 178   for (i = 0; i < histogram.length (); i++)
 179     {
 180       cumulated_time += histogram[i]->count * histogram[i]->time;
 181       cumulated_size += histogram[i]->size;
 182       fprintf (file, "  %"PRId64": time:%i (%2.2f) size:%i (%2.2f)\n",
 183                (int64_t) histogram[i]->count,
 184                histogram[i]->time,
 185                cumulated_time * 100.0 / overall_time,
 186                histogram[i]->size,
 187                cumulated_size * 100.0 / overall_size);
 188    }
 189 }
 190
 191 /* Collect histogram from CFG profiles.  */
 192
 193 static void
 194 ipa_profile_generate_summary (void)
 195 {
 196   struct cgraph_node *node;
 197   gimple_stmt_iterator gsi;
 198   basic_block bb;
 199
 200   hash_table<histogram_hash> hashtable (10);
 201   histogram_pool = create_alloc_pool ("IPA histogram", sizeof (struct histogram_entry),
 202                                       10);
 203
 204   FOR_EACH_FUNCTION_WITH_GIMPLE_BODY (node)
 205     FOR_EACH_BB_FN (bb, DECL_STRUCT_FUNCTION (node->decl))
 206       {
 207         int time = 0;
 208         int size = 0;
 209         for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
 210           {
 211             gimple stmt = gsi_stmt (gsi);
 212             if (gimple_code (stmt) == GIMPLE_CALL
 213                 && !gimple_call_fndecl (stmt))
 214               {
 215                 histogram_value h;
 216                 h = gimple_histogram_value_of_type
 217                       (DECL_STRUCT_FUNCTION (node->decl),
 218                        stmt, HIST_TYPE_INDIR_CALL);
 219                 /* No need to do sanity check: gimple_ic_transform already
 220                    takes away bad histograms.  */
 221                 if (h)
 222                   {
 223                     /* counter 0 is target, counter 1 is number of execution we called target,
 224                        counter 2 is total number of executions.  */
 225                     if (h->hvalue.counters[2])
 226                       {
 227                         struct cgraph_edge * e = node->get_edge (stmt);
 228                         if (e && !e->indirect_unknown_callee)
 229                           continue;
 230                         e->indirect_info->common_target_id
 231                           = h->hvalue.counters [0];
 232                         e->indirect_info->common_target_probability
 233                           = GCOV_COMPUTE_SCALE (h->hvalue.counters [1], h->hvalue.counters [2]);
 234                         if (e->indirect_info->common_target_probability > REG_BR_PROB_BASE)
 235                           {
 236                             if (dump_file)
 237                               fprintf (dump_file, "Probability capped to 1\n");
 238                             e->indirect_info->common_target_probability = REG_BR_PROB_BASE;
 239                           }
 240                       }
 241                     gimple_remove_histogram_value (DECL_STRUCT_FUNCTION (node->decl),
 242                                                     stmt, h);
 243                   }
 244               }
 245             time += estimate_num_insns (stmt, &eni_time_weights);
 246             size += estimate_num_insns (stmt, &eni_size_weights);
 247           }
 248         account_time_size (&hashtable, histogram, bb->count, time, size);
 249       }
 250   histogram.qsort (cmp_counts);
 251 }
 252
 253 /* Serialize the ipa info for lto.  */
 254
 255 static void
 256 ipa_profile_write_summary (void)
 257 {
 258   struct lto_simple_output_block *ob
 259     = lto_create_simple_output_block (LTO_section_ipa_profile);
 260   unsigned int i;
 261
 262   streamer_write_uhwi_stream (ob->main_stream, histogram.length ());
 263   for (i = 0; i < histogram.length (); i++)
 264     {
 265       streamer_write_gcov_count_stream (ob->main_stream, histogram[i]->count);
 266       streamer_write_uhwi_stream (ob->main_stream, histogram[i]->time);
 267       streamer_write_uhwi_stream (ob->main_stream, histogram[i]->size);
 268     }
 269   lto_destroy_simple_output_block (ob);
 270 }
 271
 272 /* Deserialize the ipa info for lto.  */
 273
 274 static void
 275 ipa_profile_read_summary (void)
 276 {
 277   struct lto_file_decl_data ** file_data_vec
 278     = lto_get_file_decl_data ();
 279   struct lto_file_decl_data * file_data;
 280   int j = 0;
 281
 282   hash_table<histogram_hash> hashtable (10);
 283   histogram_pool = create_alloc_pool ("IPA histogram", sizeof (struct histogram_entry),
 284                                       10);
 285
 286   while ((file_data = file_data_vec[j++]))
 287     {
 288       const char *data;
 289       size_t len;
 290       struct lto_input_block *ib
 291         = lto_create_simple_input_block (file_data,
 292                                          LTO_section_ipa_profile,
 293                                          &data, &len);
 294       if (ib)
 295         {
 296           unsigned int num = streamer_read_uhwi (ib);
 297           unsigned int n;
 298           for (n = 0; n < num; n++)
 299             {
 300               gcov_type count = streamer_read_gcov_count (ib);
 301               int time = streamer_read_uhwi (ib);
 302               int size = streamer_read_uhwi (ib);
 303               account_time_size (&hashtable, histogram,
 304                                  count, time, size);
 305             }
 306           lto_destroy_simple_input_block (file_data,
 307                                           LTO_section_ipa_profile,
 308                                           ib, data, len);
 309         }
 310     }
 311   histogram.qsort (cmp_counts);
 312 }
 313
 314 /* Data used by ipa_propagate_frequency.  */
 315
 316 struct ipa_propagate_frequency_data
 317 {
 318   bool maybe_unlikely_executed;
 319   bool maybe_executed_once;
 320   bool only_called_at_startup;
 321   bool only_called_at_exit;
 322 };
 323
 324 /* Worker for ipa_propagate_frequency_1.  */
 325
 326 static bool
 327 ipa_propagate_frequency_1 (struct cgraph_node *node, void *data)
 328 {
 329   struct ipa_propagate_frequency_data *d;
 330   struct cgraph_edge *edge;
 331
 332   d = (struct ipa_propagate_frequency_data *)data;
 333   for (edge = node->callers;
 334        edge && (d->maybe_unlikely_executed || d->maybe_executed_once
 335                 || d->only_called_at_startup || d->only_called_at_exit);
 336        edge = edge->next_caller)
 337     {
 338       if (edge->caller != node)
 339         {
 340           d->only_called_at_startup &= edge->caller->only_called_at_startup;
 341           /* It makes sense to put main() together with the static constructors.
 342              It will be executed for sure, but rest of functions called from
 343              main are definitely not at startup only.  */
 344           if (MAIN_NAME_P (DECL_NAME (edge->caller->decl)))
 345             d->only_called_at_startup = 0;
 346           d->only_called_at_exit &= edge->caller->only_called_at_exit;
 347         }
 348
 349       /* When profile feedback is available, do not try to propagate too hard;
 350          counts are already good guide on function frequencies and roundoff
 351          errors can make us to push function into unlikely section even when
 352          it is executed by the train run.  Transfer the function only if all
 353          callers are unlikely executed.  */
 354       if (profile_info && flag_branch_probabilities
 355           && (edge->caller->frequency != NODE_FREQUENCY_UNLIKELY_EXECUTED
 356               || (edge->caller->global.inlined_to
 357                   && edge->caller->global.inlined_to->frequency
 358                      != NODE_FREQUENCY_UNLIKELY_EXECUTED)))
 359           d->maybe_unlikely_executed = false;
 360       if (!edge->frequency)
 361         continue;
 362       switch (edge->caller->frequency)
 363         {
 364         case NODE_FREQUENCY_UNLIKELY_EXECUTED:
 365           break;
 366         case NODE_FREQUENCY_EXECUTED_ONCE:
 367           if (dump_file && (dump_flags & TDF_DETAILS))
 368             fprintf (dump_file, "  Called by %s that is executed once\n",
 369                      edge->caller->name ());
 370           d->maybe_unlikely_executed = false;
 371           if (inline_edge_summary (edge)->loop_depth)
 372             {
 373               d->maybe_executed_once = false;
 374               if (dump_file && (dump_flags & TDF_DETAILS))
 375                 fprintf (dump_file, "  Called in loop\n");
 376             }
 377           break;
 378         case NODE_FREQUENCY_HOT:
 379         case NODE_FREQUENCY_NORMAL:
 380           if (dump_file && (dump_flags & TDF_DETAILS))
 381             fprintf (dump_file, "  Called by %s that is normal or hot\n",
 382                      edge->caller->name ());
 383           d->maybe_unlikely_executed = false;
 384           d->maybe_executed_once = false;
 385           break;
 386         }
 387     }
 388   return edge != NULL;
 389 }
 390
 391 /* Return ture if NODE contains hot calls.  */
 392
 393 bool
 394 contains_hot_call_p (struct cgraph_node *node)
 395 {
 396   struct cgraph_edge *e;
 397   for (e = node->callees; e; e = e->next_callee)
 398     if (e->maybe_hot_p ())
 399       return true;
 400     else if (!e->inline_failed
 401              && contains_hot_call_p (e->callee))
 402       return true;
 403   for (e = node->indirect_calls; e; e = e->next_callee)
 404     if (e->maybe_hot_p ())
 405       return true;
 406   return false;
 407 }
 408
 409 /* See if the frequency of NODE can be updated based on frequencies of its
 410    callers.  */
 411 bool
 412 ipa_propagate_frequency (struct cgraph_node *node)
 413 {
 414   struct ipa_propagate_frequency_data d = {true, true, true, true};
 415   bool changed = false;
 416
 417   /* We can not propagate anything useful about externally visible functions
 418      nor about virtuals.  */
 419   if (!node->local.local
 420       || node->alias
 421       || (flag_devirtualize && DECL_VIRTUAL_P (node->decl)))
 422     return false;
 423   gcc_assert (node->analyzed);
 424   if (dump_file && (dump_flags & TDF_DETAILS))
 425     fprintf (dump_file, "Processing frequency %s\n", node->name ());
 426
 427   node->call_for_symbol_thunks_and_aliases (ipa_propagate_frequency_1, &d,
 428                                             true);
 429
 430   if ((d.only_called_at_startup && !d.only_called_at_exit)
 431       && !node->only_called_at_startup)
 432     {
 433        node->only_called_at_startup = true;
 434        if (dump_file)
 435          fprintf (dump_file, "Node %s promoted to only called at startup.\n",
 436                   node->name ());
 437        changed = true;
 438     }
 439   if ((d.only_called_at_exit && !d.only_called_at_startup)
 440       && !node->only_called_at_exit)
 441     {
 442        node->only_called_at_exit = true;
 443        if (dump_file)
 444          fprintf (dump_file, "Node %s promoted to only called at exit.\n",
 445                   node->name ());
 446        changed = true;
 447     }
 448
 449   /* With profile we can decide on hot/normal based on count.  */
 450   if (node->count)
 451     {
 452       bool hot = false;
 453       if (node->count >= get_hot_bb_threshold ())
 454         hot = true;
 455       if (!hot)
 456         hot |= contains_hot_call_p (node);
 457       if (hot)
 458         {
 459           if (node->frequency != NODE_FREQUENCY_HOT)
 460             {
 461               if (dump_file)
 462                 fprintf (dump_file, "Node %s promoted to hot.\n",
 463                          node->name ());
 464               node->frequency = NODE_FREQUENCY_HOT;
 465               return true;
 466             }
 467           return false;
 468         }
 469       else if (node->frequency == NODE_FREQUENCY_HOT)
 470         {
 471           if (dump_file)
 472             fprintf (dump_file, "Node %s reduced to normal.\n",
 473                      node->name ());
 474           node->frequency = NODE_FREQUENCY_NORMAL;
 475           changed = true;
 476         }
 477     }
 478   /* These come either from profile or user hints; never update them.  */
 479   if (node->frequency == NODE_FREQUENCY_HOT
 480       || node->frequency == NODE_FREQUENCY_UNLIKELY_EXECUTED)
 481     return changed;
 482   if (d.maybe_unlikely_executed)
 483     {
 484       node->frequency = NODE_FREQUENCY_UNLIKELY_EXECUTED;
 485       if (dump_file)
 486         fprintf (dump_file, "Node %s promoted to unlikely executed.\n",
 487                  node->name ());
 488       changed = true;
 489     }
 490   else if (d.maybe_executed_once && node->frequency != NODE_FREQUENCY_EXECUTED_ONCE)
 491     {
 492       node->frequency = NODE_FREQUENCY_EXECUTED_ONCE;
 493       if (dump_file)
 494         fprintf (dump_file, "Node %s promoted to executed once.\n",
 495                  node->name ());
 496       changed = true;
 497     }
 498   return changed;
 499 }
 500
 501 /* Simple ipa profile pass propagating frequencies across the callgraph.  */
 502
 503 static unsigned int
 504 ipa_profile (void)
 505 {
 506   struct cgraph_node **order;
 507   struct cgraph_edge *e;
 508   int order_pos;
 509   bool something_changed = false;
 510   int i;
 511   gcov_type overall_time = 0, cutoff = 0, cumulated = 0, overall_size = 0;
 512   struct cgraph_node *n,*n2;
 513   int nindirect = 0, ncommon = 0, nunknown = 0, nuseless = 0, nconverted = 0;
 514   bool node_map_initialized = false;
 515
 516   if (dump_file)
 517     dump_histogram (dump_file, histogram);
 518   for (i = 0; i < (int)histogram.length (); i++)
 519     {
 520       overall_time += histogram[i]->count * histogram[i]->time;
 521       overall_size += histogram[i]->size;
 522     }
 523   if (overall_time)
 524     {
 525       gcov_type threshold;
 526
 527       gcc_assert (overall_size);
 528       if (dump_file)
 529         {
 530           gcov_type min, cumulated_time = 0, cumulated_size = 0;
 531
 532           fprintf (dump_file, "Overall time: %"PRId64"\n",
 533                    (int64_t)overall_time);
 534           min = get_hot_bb_threshold ();
 535           for (i = 0; i < (int)histogram.length () && histogram[i]->count >= min;
 536                i++)
 537             {
 538               cumulated_time += histogram[i]->count * histogram[i]->time;
 539               cumulated_size += histogram[i]->size;
 540             }
 541           fprintf (dump_file, "GCOV min count: %"PRId64
 542                    " Time:%3.2f%% Size:%3.2f%%\n",
 543                    (int64_t)min,
 544                    cumulated_time * 100.0 / overall_time,
 545                    cumulated_size * 100.0 / overall_size);
 546         }
 547       cutoff = (overall_time * PARAM_VALUE (HOT_BB_COUNT_WS_PERMILLE) + 500) / 1000;
 548       threshold = 0;
 549       for (i = 0; cumulated < cutoff; i++)
 550         {
 551           cumulated += histogram[i]->count * histogram[i]->time;
 552           threshold = histogram[i]->count;
 553         }
 554       if (!threshold)
 555         threshold = 1;
 556       if (dump_file)
 557         {
 558           gcov_type cumulated_time = 0, cumulated_size = 0;
 559
 560           for (i = 0;
 561                i < (int)histogram.length () && histogram[i]->count >= threshold;
 562                i++)
 563             {
 564               cumulated_time += histogram[i]->count * histogram[i]->time;
 565               cumulated_size += histogram[i]->size;
 566             }
 567           fprintf (dump_file, "Determined min count: %"PRId64
 568                    " Time:%3.2f%% Size:%3.2f%%\n",
 569                    (int64_t)threshold,
 570                    cumulated_time * 100.0 / overall_time,
 571                    cumulated_size * 100.0 / overall_size);
 572         }
 573       if (threshold > get_hot_bb_threshold ()
 574           || in_lto_p)
 575         {
 576           if (dump_file)
 577             fprintf (dump_file, "Threshold updated.\n");
 578           set_hot_bb_threshold (threshold);
 579         }
 580     }
 581   histogram.release ();
 582   free_alloc_pool (histogram_pool);
 583
 584   /* Produce speculative calls: we saved common traget from porfiling into
 585      e->common_target_id.  Now, at link time, we can look up corresponding
 586      function node and produce speculative call.  */
 587
 588   FOR_EACH_DEFINED_FUNCTION (n)
 589     {
 590       bool update = false;
 591
 592       for (e = n->indirect_calls; e; e = e->next_callee)
 593         {
 594           if (n->count)
 595             nindirect++;
 596           if (e->indirect_info->common_target_id)
 597             {
 598               if (!node_map_initialized)
 599                 init_node_map (false);
 600               node_map_initialized = true;
 601               ncommon++;
 602               n2 = find_func_by_profile_id (e->indirect_info->common_target_id);
 603               if (n2)
 604                 {
 605                   if (dump_file)
 606                     {
 607                       fprintf (dump_file, "Indirect call -> direct call from"
 608                                " other module %s/%i => %s/%i, prob %3.2f\n",
 609                                xstrdup (n->name ()), n->order,
 610                                xstrdup (n2->name ()), n2->order,
 611                                e->indirect_info->common_target_probability
 612                                / (float)REG_BR_PROB_BASE);
 613                     }
 614                   if (e->indirect_info->common_target_probability
 615                       < REG_BR_PROB_BASE / 2)
 616                     {
 617                       nuseless++;
 618                       if (dump_file)
 619                         fprintf (dump_file,
 620                                  "Not speculating: probability is too low.\n");
 621                     }
 622                   else if (!e->maybe_hot_p ())
 623                     {
 624                       nuseless++;
 625                       if (dump_file)
 626                         fprintf (dump_file,
 627                                  "Not speculating: call is cold.\n");
 628                     }
 629                   else if (n2->get_availability () <= AVAIL_INTERPOSABLE
 630                            && n2->can_be_discarded_p ())
 631                     {
 632                       nuseless++;
 633                       if (dump_file)
 634                         fprintf (dump_file,
 635                                  "Not speculating: target is overwritable "
 636                                  "and can be discarded.\n");
 637                     }
 638                   else
 639                     {
 640                       /* Target may be overwritable, but profile says that
 641                          control flow goes to this particular implementation
 642                          of N2.  Speculate on the local alias to allow inlining.
 643                        */
 644                       if (!n2->can_be_discarded_p ())
 645                         {
 646                           cgraph_node *alias;
 647                           alias = dyn_cast<cgraph_node *> (n2->noninterposable_alias ());
 648                           if (alias)
 649                             n2 = alias;
 650                         }
 651                       nconverted++;
 652                       e->make_speculative
 653                         (n2,
 654                          apply_scale (e->count,
 655                                       e->indirect_info->common_target_probability),
 656                          apply_scale (e->frequency,
 657                                       e->indirect_info->common_target_probability));
 658                       update = true;
 659                     }
 660                 }
 661               else
 662                 {
 663                   if (dump_file)
 664                     fprintf (dump_file, "Function with profile-id %i not found.\n",
 665                              e->indirect_info->common_target_id);
 666                   nunknown++;
 667                 }
 668             }
 669          }
 670        if (update)
 671          inline_update_overall_summary (n);
 672      }
 673   if (node_map_initialized)
 674     del_node_map ();
 675   if (dump_file && nindirect)
 676     fprintf (dump_file,
 677              "%i indirect calls trained.\n"
 678              "%i (%3.2f%%) have common target.\n"
 679              "%i (%3.2f%%) targets was not found.\n"
 680              "%i (%3.2f%%) speculations seems useless.\n"
 681              "%i (%3.2f%%) speculations produced.\n",
 682              nindirect,
 683              ncommon, ncommon * 100.0 / nindirect,
 684              nunknown, nunknown * 100.0 / nindirect,
 685              nuseless, nuseless * 100.0 / nindirect,
 686              nconverted, nconverted * 100.0 / nindirect);
 687
 688   order = XCNEWVEC (struct cgraph_node *, symtab->cgraph_count);
 689   order_pos = ipa_reverse_postorder (order);
 690   for (i = order_pos - 1; i >= 0; i--)
 691     {
 692       if (order[i]->local.local && ipa_propagate_frequency (order[i]))
 693         {
 694           for (e = order[i]->callees; e; e = e->next_callee)
 695             if (e->callee->local.local && !e->callee->aux)
 696               {
 697                 something_changed = true;
 698                 e->callee->aux = (void *)1;
 699               }
 700         }
 701       order[i]->aux = NULL;
 702     }
 703
 704   while (something_changed)
 705     {
 706       something_changed = false;
 707       for (i = order_pos - 1; i >= 0; i--)
 708         {
 709           if (order[i]->aux && ipa_propagate_frequency (order[i]))
 710             {
 711               for (e = order[i]->callees; e; e = e->next_callee)
 712                 if (e->callee->local.local && !e->callee->aux)
 713                   {
 714                     something_changed = true;
 715                     e->callee->aux = (void *)1;
 716                   }
 717             }
 718           order[i]->aux = NULL;
 719         }
 720     }
 721   free (order);
 722   return 0;
 723 }
 724
 725 namespace {
 726
 727 const pass_data pass_data_ipa_profile =
 728 {
 729   IPA_PASS, /* type */
 730   "profile_estimate", /* name */
 731   OPTGROUP_NONE, /* optinfo_flags */
 732   TV_IPA_PROFILE, /* tv_id */
 733   0, /* properties_required */
 734   0, /* properties_provided */
 735   0, /* properties_destroyed */
 736   0, /* todo_flags_start */
 737   0, /* todo_flags_finish */
 738 };
 739
 740 class pass_ipa_profile : public ipa_opt_pass_d
 741 {
 742 public:
 743   pass_ipa_profile (gcc::context *ctxt)
 744     : ipa_opt_pass_d (pass_data_ipa_profile, ctxt,
 745                       ipa_profile_generate_summary, /* generate_summary */
 746                       ipa_profile_write_summary, /* write_summary */
 747                       ipa_profile_read_summary, /* read_summary */
 748                       NULL, /* write_optimization_summary */
 749                       NULL, /* read_optimization_summary */
 750                       NULL, /* stmt_fixup */
 751                       0, /* function_transform_todo_flags_start */
 752                       NULL, /* function_transform */
 753                       NULL) /* variable_transform */
 754   {}
 755
 756   /* opt_pass methods: */
 757   virtual bool gate (function *) { return flag_ipa_profile; }
 758   virtual unsigned int execute (function *) { return ipa_profile (); }
 759
 760 }; // class pass_ipa_profile
 761
 762 } // anon namespace
 763
 764 ipa_opt_pass_d *
 765 make_pass_ipa_profile (gcc::context *ctxt)
 766 {
 767   return new pass_ipa_profile (ctxt);
 768 }