gcc/value-prof.c

   1 /* Transformations based on profile information for values.
   2    Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Free Software
   3    Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #include "config.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "tm.h"
  25 #include "rtl.h"
  26 #include "expr.h"
  27 #include "hard-reg-set.h"
  28 #include "basic-block.h"
  29 #include "value-prof.h"
  30 #include "output.h"
  31 #include "flags.h"
  32 #include "insn-config.h"
  33 #include "recog.h"
  34 #include "optabs.h"
  35 #include "regs.h"
  36 #include "ggc.h"
  37 #include "tree-flow.h"
  38 #include "tree-flow-inline.h"
  39 #include "diagnostic.h"
  40 #include "coverage.h"
  41 #include "tree.h"
  42 #include "gcov-io.h"
  43 #include "cgraph.h"
  44 #include "timevar.h"
  45 #include "tree-pass.h"
  46 #include "toplev.h"
  47 #include "pointer-set.h"
  48
  49 static struct value_prof_hooks *value_prof_hooks;
  50
  51 /* In this file value profile based optimizations are placed.  Currently the
  52    following optimizations are implemented (for more detailed descriptions
  53    see comments at value_profile_transformations):
  54
  55    1) Division/modulo specialization.  Provided that we can determine that the
  56       operands of the division have some special properties, we may use it to
  57       produce more effective code.
  58    2) Speculative prefetching.  If we are able to determine that the difference
  59       between addresses accessed by a memory reference is usually constant, we
  60       may add the prefetch instructions.
  61       FIXME: This transformation was removed together with RTL based value
  62       profiling.
  63
  64    3) Indirect/virtual call specialization. If we can determine most
  65       common function callee in indirect/virtual call. We can use this
  66       information to improve code effectiveness (especially info for
  67       inliner).
  68
  69    Every such optimization should add its requirements for profiled values to
  70    insn_values_to_profile function.  This function is called from branch_prob
  71    in profile.c and the requested values are instrumented by it in the first
  72    compilation with -fprofile-arcs.  The optimization may then read the
  73    gathered data in the second compilation with -fbranch-probabilities.
  74
  75    The measured data is pointed to from the histograms
  76    field of the statement annotation of the instrumented insns.  It is
  77    kept as a linked list of struct histogram_value_t's, which contain the
  78    same information as above.  */
  79
  80
  81 static tree gimple_divmod_fixed_value (gimple, tree, int, gcov_type, gcov_type);
  82 static tree gimple_mod_pow2 (gimple, int, gcov_type, gcov_type);
  83 static tree gimple_mod_subtract (gimple, int, int, int, gcov_type, gcov_type,
  84                                  gcov_type);
  85 static bool gimple_divmod_fixed_value_transform (gimple_stmt_iterator *);
  86 static bool gimple_mod_pow2_value_transform (gimple_stmt_iterator *);
  87 static bool gimple_mod_subtract_transform (gimple_stmt_iterator *);
  88 static bool gimple_stringops_transform (gimple_stmt_iterator *);
  89 static bool gimple_ic_transform (gimple);
  90
  91 /* Allocate histogram value.  */
  92
  93 static histogram_value
  94 gimple_alloc_histogram_value (struct function *fun ATTRIBUTE_UNUSED,
  95                               enum hist_type type, gimple stmt, tree value)
  96 {
  97    histogram_value hist = (histogram_value) xcalloc (1, sizeof (*hist));
  98    hist->hvalue.value = value;
  99    hist->hvalue.stmt = stmt;
 100    hist->type = type;
 101    return hist;
 102 }
 103
 104 /* Hash value for histogram.  */
 105
 106 static hashval_t
 107 histogram_hash (const void *x)
 108 {
 109   return htab_hash_pointer (((const_histogram_value)x)->hvalue.stmt);
 110 }
 111
 112 /* Return nonzero if decl_id of die_struct X is the same as UID of decl *Y.  */
 113
 114 static int
 115 histogram_eq (const void *x, const void *y)
 116 {
 117   return ((const_histogram_value) x)->hvalue.stmt == (const_gimple) y;
 118 }
 119
 120 /* Set histogram for STMT.  */
 121
 122 static void
 123 set_histogram_value (struct function *fun, gimple stmt, histogram_value hist)
 124 {
 125   void **loc;
 126   if (!hist && !VALUE_HISTOGRAMS (fun))
 127     return;
 128   if (!VALUE_HISTOGRAMS (fun))
 129     VALUE_HISTOGRAMS (fun) = htab_create (1, histogram_hash,
 130                                            histogram_eq, NULL);
 131   loc = htab_find_slot_with_hash (VALUE_HISTOGRAMS (fun), stmt,
 132                                   htab_hash_pointer (stmt),
 133                                   hist ? INSERT : NO_INSERT);
 134   if (!hist)
 135     {
 136       if (loc)
 137         htab_clear_slot (VALUE_HISTOGRAMS (fun), loc);
 138       return;
 139     }
 140   *loc = hist;
 141 }
 142
 143 /* Get histogram list for STMT.  */
 144
 145 histogram_value
 146 gimple_histogram_value (struct function *fun, gimple stmt)
 147 {
 148   if (!VALUE_HISTOGRAMS (fun))
 149     return NULL;
 150   return (histogram_value) htab_find_with_hash (VALUE_HISTOGRAMS (fun), stmt,
 151                                                 htab_hash_pointer (stmt));
 152 }
 153
 154 /* Add histogram for STMT.  */
 155
 156 void
 157 gimple_add_histogram_value (struct function *fun, gimple stmt,
 158                             histogram_value hist)
 159 {
 160   hist->hvalue.next = gimple_histogram_value (fun, stmt);
 161   set_histogram_value (fun, stmt, hist);
 162 }
 163
 164
 165 /* Remove histogram HIST from STMT's histogram list.  */
 166
 167 void
 168 gimple_remove_histogram_value (struct function *fun, gimple stmt,
 169                                histogram_value hist)
 170 {
 171   histogram_value hist2 = gimple_histogram_value (fun, stmt);
 172   if (hist == hist2)
 173     {
 174       set_histogram_value (fun, stmt, hist->hvalue.next);
 175     }
 176   else
 177     {
 178       while (hist2->hvalue.next != hist)
 179         hist2 = hist2->hvalue.next;
 180       hist2->hvalue.next = hist->hvalue.next;
 181     }
 182   free (hist->hvalue.counters);
 183 #ifdef ENABLE_CHECKING
 184   memset (hist, 0xab, sizeof (*hist));
 185 #endif
 186   free (hist);
 187 }
 188
 189
 190 /* Lookup histogram of type TYPE in the STMT.  */
 191
 192 histogram_value
 193 gimple_histogram_value_of_type (struct function *fun, gimple stmt,
 194                                 enum hist_type type)
 195 {
 196   histogram_value hist;
 197   for (hist = gimple_histogram_value (fun, stmt); hist;
 198        hist = hist->hvalue.next)
 199     if (hist->type == type)
 200       return hist;
 201   return NULL;
 202 }
 203
 204 /* Dump information about HIST to DUMP_FILE.  */
 205
 206 static void
 207 dump_histogram_value (FILE *dump_file, histogram_value hist)
 208 {
 209   switch (hist->type)
 210     {
 211     case HIST_TYPE_INTERVAL:
 212       fprintf (dump_file, "Interval counter range %d -- %d",
 213                hist->hdata.intvl.int_start,
 214                (hist->hdata.intvl.int_start
 215                 + hist->hdata.intvl.steps - 1));
 216       if (hist->hvalue.counters)
 217         {
 218            unsigned int i;
 219            fprintf(dump_file, " [");
 220            for (i = 0; i < hist->hdata.intvl.steps; i++)
 221              fprintf (dump_file, " %d:"HOST_WIDEST_INT_PRINT_DEC,
 222                       hist->hdata.intvl.int_start + i,
 223                       (HOST_WIDEST_INT) hist->hvalue.counters[i]);
 224            fprintf (dump_file, " ] outside range:"HOST_WIDEST_INT_PRINT_DEC,
 225                     (HOST_WIDEST_INT) hist->hvalue.counters[i]);
 226         }
 227       fprintf (dump_file, ".\n");
 228       break;
 229
 230     case HIST_TYPE_POW2:
 231       fprintf (dump_file, "Pow2 counter ");
 232       if (hist->hvalue.counters)
 233         {
 234            fprintf (dump_file, "pow2:"HOST_WIDEST_INT_PRINT_DEC
 235                     " nonpow2:"HOST_WIDEST_INT_PRINT_DEC,
 236                     (HOST_WIDEST_INT) hist->hvalue.counters[0],
 237                     (HOST_WIDEST_INT) hist->hvalue.counters[1]);
 238         }
 239       fprintf (dump_file, ".\n");
 240       break;
 241
 242     case HIST_TYPE_SINGLE_VALUE:
 243       fprintf (dump_file, "Single value ");
 244       if (hist->hvalue.counters)
 245         {
 246            fprintf (dump_file, "value:"HOST_WIDEST_INT_PRINT_DEC
 247                     " match:"HOST_WIDEST_INT_PRINT_DEC
 248                     " wrong:"HOST_WIDEST_INT_PRINT_DEC,
 249                     (HOST_WIDEST_INT) hist->hvalue.counters[0],
 250                     (HOST_WIDEST_INT) hist->hvalue.counters[1],
 251                     (HOST_WIDEST_INT) hist->hvalue.counters[2]);
 252         }
 253       fprintf (dump_file, ".\n");
 254       break;
 255
 256     case HIST_TYPE_AVERAGE:
 257       fprintf (dump_file, "Average value ");
 258       if (hist->hvalue.counters)
 259         {
 260            fprintf (dump_file, "sum:"HOST_WIDEST_INT_PRINT_DEC
 261                     " times:"HOST_WIDEST_INT_PRINT_DEC,
 262                     (HOST_WIDEST_INT) hist->hvalue.counters[0],
 263                     (HOST_WIDEST_INT) hist->hvalue.counters[1]);
 264         }
 265       fprintf (dump_file, ".\n");
 266       break;
 267
 268     case HIST_TYPE_IOR:
 269       fprintf (dump_file, "IOR value ");
 270       if (hist->hvalue.counters)
 271         {
 272            fprintf (dump_file, "ior:"HOST_WIDEST_INT_PRINT_DEC,
 273                     (HOST_WIDEST_INT) hist->hvalue.counters[0]);
 274         }
 275       fprintf (dump_file, ".\n");
 276       break;
 277
 278     case HIST_TYPE_CONST_DELTA:
 279       fprintf (dump_file, "Constant delta ");
 280       if (hist->hvalue.counters)
 281         {
 282            fprintf (dump_file, "value:"HOST_WIDEST_INT_PRINT_DEC
 283                     " match:"HOST_WIDEST_INT_PRINT_DEC
 284                     " wrong:"HOST_WIDEST_INT_PRINT_DEC,
 285                     (HOST_WIDEST_INT) hist->hvalue.counters[0],
 286                     (HOST_WIDEST_INT) hist->hvalue.counters[1],
 287                     (HOST_WIDEST_INT) hist->hvalue.counters[2]);
 288         }
 289       fprintf (dump_file, ".\n");
 290       break;
 291     case HIST_TYPE_INDIR_CALL:
 292       fprintf (dump_file, "Indirect call ");
 293       if (hist->hvalue.counters)
 294         {
 295            fprintf (dump_file, "value:"HOST_WIDEST_INT_PRINT_DEC
 296                     " match:"HOST_WIDEST_INT_PRINT_DEC
 297                     " all:"HOST_WIDEST_INT_PRINT_DEC,
 298                     (HOST_WIDEST_INT) hist->hvalue.counters[0],
 299                     (HOST_WIDEST_INT) hist->hvalue.counters[1],
 300                     (HOST_WIDEST_INT) hist->hvalue.counters[2]);
 301         }
 302       fprintf (dump_file, ".\n");
 303       break;
 304    }
 305 }
 306
 307 /* Dump all histograms attached to STMT to DUMP_FILE.  */
 308
 309 void
 310 dump_histograms_for_stmt (struct function *fun, FILE *dump_file, gimple stmt)
 311 {
 312   histogram_value hist;
 313   for (hist = gimple_histogram_value (fun, stmt); hist; hist = hist->hvalue.next)
 314    dump_histogram_value (dump_file, hist);
 315 }
 316
 317 /* Remove all histograms associated with STMT.  */
 318
 319 void
 320 gimple_remove_stmt_histograms (struct function *fun, gimple stmt)
 321 {
 322   histogram_value val;
 323   while ((val = gimple_histogram_value (fun, stmt)) != NULL)
 324     gimple_remove_histogram_value (fun, stmt, val);
 325 }
 326
 327 /* Duplicate all histograms associates with OSTMT to STMT.  */
 328
 329 void
 330 gimple_duplicate_stmt_histograms (struct function *fun, gimple stmt,
 331                                   struct function *ofun, gimple ostmt)
 332 {
 333   histogram_value val;
 334   for (val = gimple_histogram_value (ofun, ostmt); val != NULL; val = val->hvalue.next)
 335     {
 336       histogram_value new_val = gimple_alloc_histogram_value (fun, val->type, NULL, NULL);
 337       memcpy (new_val, val, sizeof (*val));
 338       new_val->hvalue.stmt = stmt;
 339       new_val->hvalue.counters = XNEWVAR (gcov_type, sizeof (*new_val->hvalue.counters) * new_val->n_counters);
 340       memcpy (new_val->hvalue.counters, val->hvalue.counters, sizeof (*new_val->hvalue.counters) * new_val->n_counters);
 341       gimple_add_histogram_value (fun, stmt, new_val);
 342     }
 343 }
 344
 345
 346 /* Move all histograms associated with OSTMT to STMT.  */
 347
 348 void
 349 gimple_move_stmt_histograms (struct function *fun, gimple stmt, gimple ostmt)
 350 {
 351   histogram_value val = gimple_histogram_value (fun, ostmt);
 352   if (val)
 353     {
 354       /* The following three statements can't be reordered,
 355          because histogram hashtab relies on stmt field value
 356          for finding the exact slot. */
 357       set_histogram_value (fun, ostmt, NULL);
 358       for (; val != NULL; val = val->hvalue.next)
 359         val->hvalue.stmt = stmt;
 360       set_histogram_value (fun, stmt, val);
 361     }
 362 }
 363
 364 static bool error_found = false;
 365
 366 /* Helper function for verify_histograms.  For each histogram reachable via htab
 367    walk verify that it was reached via statement walk.  */
 368
 369 static int
 370 visit_hist (void **slot, void *data)
 371 {
 372   struct pointer_set_t *visited = (struct pointer_set_t *) data;
 373   histogram_value hist = *(histogram_value *) slot;
 374   if (!pointer_set_contains (visited, hist))
 375     {
 376       error ("Dead histogram");
 377       dump_histogram_value (stderr, hist);
 378       debug_gimple_stmt (hist->hvalue.stmt);
 379       error_found = true;
 380     }
 381   return 1;
 382 }
 383
 384
 385 /* Verify sanity of the histograms.  */
 386
 387 void
 388 verify_histograms (void)
 389 {
 390   basic_block bb;
 391   gimple_stmt_iterator gsi;
 392   histogram_value hist;
 393   struct pointer_set_t *visited_hists;
 394
 395   error_found = false;
 396   visited_hists = pointer_set_create ();
 397   FOR_EACH_BB (bb)
 398     for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
 399       {
 400         gimple stmt = gsi_stmt (gsi);
 401
 402         for (hist = gimple_histogram_value (cfun, stmt); hist;
 403              hist = hist->hvalue.next)
 404           {
 405             if (hist->hvalue.stmt != stmt)
 406               {
 407                 error ("Histogram value statement does not correspond to "
 408                        "the statement it is associated with");
 409                 debug_gimple_stmt (stmt);
 410                 dump_histogram_value (stderr, hist);
 411                 error_found = true;
 412               }
 413             pointer_set_insert (visited_hists, hist);
 414           }
 415       }
 416   if (VALUE_HISTOGRAMS (cfun))
 417     htab_traverse (VALUE_HISTOGRAMS (cfun), visit_hist, visited_hists);
 418   pointer_set_destroy (visited_hists);
 419   if (error_found)
 420     internal_error ("verify_histograms failed");
 421 }
 422
 423 /* Helper function for verify_histograms.  For each histogram reachable via htab
 424    walk verify that it was reached via statement walk.  */
 425
 426 static int
 427 free_hist (void **slot, void *data ATTRIBUTE_UNUSED)
 428 {
 429   histogram_value hist = *(histogram_value *) slot;
 430   free (hist->hvalue.counters);
 431 #ifdef ENABLE_CHECKING
 432   memset (hist, 0xab, sizeof (*hist));
 433 #endif
 434   free (hist);
 435   return 1;
 436 }
 437
 438 void
 439 free_histograms (void)
 440 {
 441   if (VALUE_HISTOGRAMS (cfun))
 442     {
 443       htab_traverse (VALUE_HISTOGRAMS (cfun), free_hist, NULL);
 444       htab_delete (VALUE_HISTOGRAMS (cfun));
 445       VALUE_HISTOGRAMS (cfun) = NULL;
 446     }
 447 }
 448
 449
 450 /* The overall number of invocations of the counter should match
 451    execution count of basic block.  Report it as error rather than
 452    internal error as it might mean that user has misused the profile
 453    somehow.  */
 454
 455 static bool
 456 check_counter (gimple stmt, const char * name,
 457                gcov_type *count, gcov_type *all, gcov_type bb_count)
 458 {
 459   if (*all != bb_count || *count > *all)
 460     {
 461       location_t locus;
 462       locus = (stmt != NULL)
 463               ? gimple_location (stmt)
 464               : DECL_SOURCE_LOCATION (current_function_decl);
 465       if (flag_profile_correction)
 466         {
 467           inform (locus, "Correcting inconsistent value profile: "
 468                   "%s profiler overall count (%d) does not match BB count "
 469                   "(%d)", name, (int)*all, (int)bb_count);
 470           *all = bb_count;
 471           if (*count > *all)
 472             *count = *all;
 473           return false;
 474         }
 475       else
 476         {
 477           error ("%HCorrupted value profile: %s profiler overall count (%d) "
 478                  "does not match BB count (%d)", &locus, name, (int)*all,
 479                  (int)bb_count);
 480           return true;
 481         }
 482     }
 483
 484   return false;
 485 }
 486
 487
 488 /* GIMPLE based transformations. */
 489
 490 static bool
 491 gimple_value_profile_transformations (void)
 492 {
 493   basic_block bb;
 494   gimple_stmt_iterator gsi;
 495   bool changed = false;
 496
 497   FOR_EACH_BB (bb)
 498     {
 499       for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
 500         {
 501           gimple stmt = gsi_stmt (gsi);
 502           histogram_value th = gimple_histogram_value (cfun, stmt);
 503           if (!th)
 504             continue;
 505
 506           if (dump_file)
 507             {
 508               fprintf (dump_file, "Trying transformations on stmt ");
 509               print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM);
 510               dump_histograms_for_stmt (cfun, dump_file, stmt);
 511             }
 512
 513           /* Transformations:  */
 514           /* The order of things in this conditional controls which
 515              transformation is used when more than one is applicable.  */
 516           /* It is expected that any code added by the transformations
 517              will be added before the current statement, and that the
 518              current statement remain valid (although possibly
 519              modified) upon return.  */
 520           if (flag_value_profile_transformations
 521               && (gimple_mod_subtract_transform (&gsi)
 522                   || gimple_divmod_fixed_value_transform (&gsi)
 523                   || gimple_mod_pow2_value_transform (&gsi)
 524                   || gimple_stringops_transform (&gsi)
 525                   || gimple_ic_transform (stmt)))
 526             {
 527               stmt = gsi_stmt (gsi);
 528               changed = true;
 529               /* Original statement may no longer be in the same block. */
 530               if (bb != gimple_bb (stmt))
 531                 {
 532                   bb = gimple_bb (stmt);
 533                   gsi = gsi_for_stmt (stmt);
 534                 }
 535             }
 536         }
 537     }
 538
 539   if (changed)
 540     {
 541       counts_to_freqs ();
 542     }
 543
 544   return changed;
 545 }
 546
 547
 548 /* Generate code for transformation 1 (with parent gimple assignment
 549    STMT and probability of taking the optimal path PROB, which is
 550    equivalent to COUNT/ALL within roundoff error).  This generates the
 551    result into a temp and returns the temp; it does not replace or
 552    alter the original STMT.  */
 553
 554 static tree
 555 gimple_divmod_fixed_value (gimple stmt, tree value, int prob, gcov_type count,
 556                            gcov_type all)
 557 {
 558   gimple stmt1, stmt2, stmt3;
 559   tree tmp1, tmp2, tmpv;
 560   gimple bb1end, bb2end, bb3end;
 561   basic_block bb, bb2, bb3, bb4;
 562   tree optype, op1, op2;
 563   edge e12, e13, e23, e24, e34;
 564   gimple_stmt_iterator gsi;
 565
 566   gcc_assert (is_gimple_assign (stmt)
 567               && (gimple_assign_rhs_code (stmt) == TRUNC_DIV_EXPR
 568                   || gimple_assign_rhs_code (stmt) == TRUNC_MOD_EXPR));
 569
 570   optype = TREE_TYPE (gimple_assign_lhs (stmt));
 571   op1 = gimple_assign_rhs1 (stmt);
 572   op2 = gimple_assign_rhs2 (stmt);
 573
 574   bb = gimple_bb (stmt);
 575   gsi = gsi_for_stmt (stmt);
 576
 577   tmpv = create_tmp_var (optype, "PROF");
 578   tmp1 = create_tmp_var (optype, "PROF");
 579   stmt1 = gimple_build_assign (tmpv, fold_convert (optype, value));
 580   stmt2 = gimple_build_assign (tmp1, op2);
 581   stmt3 = gimple_build_cond (NE_EXPR, tmp1, tmpv, NULL_TREE, NULL_TREE);
 582   gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
 583   gsi_insert_before (&gsi, stmt2, GSI_SAME_STMT);
 584   gsi_insert_before (&gsi, stmt3, GSI_SAME_STMT);
 585   bb1end = stmt3;
 586
 587   tmp2 = create_tmp_var (optype, "PROF");
 588   stmt1 = gimple_build_assign_with_ops (gimple_assign_rhs_code (stmt), tmp2,
 589                                         op1, tmpv);
 590   gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
 591   bb2end = stmt1;
 592
 593   stmt1 = gimple_build_assign_with_ops (gimple_assign_rhs_code (stmt), tmp2,
 594                                         op1, op2);
 595   gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
 596   bb3end = stmt1;
 597
 598   /* Fix CFG. */
 599   /* Edge e23 connects bb2 to bb3, etc. */
 600   e12 = split_block (bb, bb1end);
 601   bb2 = e12->dest;
 602   bb2->count = count;
 603   e23 = split_block (bb2, bb2end);
 604   bb3 = e23->dest;
 605   bb3->count = all - count;
 606   e34 = split_block (bb3, bb3end);
 607   bb4 = e34->dest;
 608   bb4->count = all;
 609
 610   e12->flags &= ~EDGE_FALLTHRU;
 611   e12->flags |= EDGE_FALSE_VALUE;
 612   e12->probability = prob;
 613   e12->count = count;
 614
 615   e13 = make_edge (bb, bb3, EDGE_TRUE_VALUE);
 616   e13->probability = REG_BR_PROB_BASE - prob;
 617   e13->count = all - count;
 618
 619   remove_edge (e23);
 620
 621   e24 = make_edge (bb2, bb4, EDGE_FALLTHRU);
 622   e24->probability = REG_BR_PROB_BASE;
 623   e24->count = count;
 624
 625   e34->probability = REG_BR_PROB_BASE;
 626   e34->count = all - count;
 627
 628   return tmp2;
 629 }
 630
 631
 632 /* Do transform 1) on INSN if applicable.  */
 633
 634 static bool
 635 gimple_divmod_fixed_value_transform (gimple_stmt_iterator *si)
 636 {
 637   histogram_value histogram;
 638   enum tree_code code;
 639   gcov_type val, count, all;
 640   tree result, value, tree_val;
 641   gcov_type prob;
 642   gimple stmt;
 643
 644   stmt = gsi_stmt (*si);
 645   if (gimple_code (stmt) != GIMPLE_ASSIGN)
 646     return false;
 647
 648   if (!INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (stmt))))
 649     return false;
 650
 651   code = gimple_assign_rhs_code (stmt);
 652
 653   if (code != TRUNC_DIV_EXPR && code != TRUNC_MOD_EXPR)
 654     return false;
 655
 656   histogram = gimple_histogram_value_of_type (cfun, stmt,
 657                                               HIST_TYPE_SINGLE_VALUE);
 658   if (!histogram)
 659     return false;
 660
 661   value = histogram->hvalue.value;
 662   val = histogram->hvalue.counters[0];
 663   count = histogram->hvalue.counters[1];
 664   all = histogram->hvalue.counters[2];
 665   gimple_remove_histogram_value (cfun, stmt, histogram);
 666
 667   /* We require that count is at least half of all; this means
 668      that for the transformation to fire the value must be constant
 669      at least 50% of time (and 75% gives the guarantee of usage).  */
 670   if (simple_cst_equal (gimple_assign_rhs2 (stmt), value) != 1
 671       || 2 * count < all
 672       || optimize_bb_for_size_p (gimple_bb (stmt)))
 673     return false;
 674
 675   if (check_counter (stmt, "value", &count, &all, gimple_bb (stmt)->count))
 676     return false;
 677
 678   /* Compute probability of taking the optimal path.  */
 679   if (all > 0)
 680     prob = (count * REG_BR_PROB_BASE + all / 2) / all;
 681   else
 682     prob = 0;
 683
 684   tree_val = build_int_cst_wide (get_gcov_type (),
 685                                  (unsigned HOST_WIDE_INT) val,
 686                                  val >> (HOST_BITS_PER_WIDE_INT - 1) >> 1);
 687   result = gimple_divmod_fixed_value (stmt, tree_val, prob, count, all);
 688
 689   if (dump_file)
 690     {
 691       fprintf (dump_file, "Div/mod by constant ");
 692       print_generic_expr (dump_file, value, TDF_SLIM);
 693       fprintf (dump_file, "=");
 694       print_generic_expr (dump_file, tree_val, TDF_SLIM);
 695       fprintf (dump_file, " transformation on insn ");
 696       print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM);
 697     }
 698
 699   gimple_assign_set_rhs_from_tree (si, result);
 700
 701   return true;
 702 }
 703
 704 /* Generate code for transformation 2 (with parent gimple assign STMT and
 705    probability of taking the optimal path PROB, which is equivalent to COUNT/ALL
 706    within roundoff error).  This generates the result into a temp and returns
 707    the temp; it does not replace or alter the original STMT.  */
 708 static tree
 709 gimple_mod_pow2 (gimple stmt, int prob, gcov_type count, gcov_type all)
 710 {
 711   gimple stmt1, stmt2, stmt3, stmt4;
 712   tree tmp2, tmp3;
 713   gimple bb1end, bb2end, bb3end;
 714   basic_block bb, bb2, bb3, bb4;
 715   tree optype, op1, op2;
 716   edge e12, e13, e23, e24, e34;
 717   gimple_stmt_iterator gsi;
 718   tree result;
 719
 720   gcc_assert (is_gimple_assign (stmt)
 721               && gimple_assign_rhs_code (stmt) == TRUNC_MOD_EXPR);
 722
 723   optype = TREE_TYPE (gimple_assign_lhs (stmt));
 724   op1 = gimple_assign_rhs1 (stmt);
 725   op2 = gimple_assign_rhs2 (stmt);
 726
 727   bb = gimple_bb (stmt);
 728   gsi = gsi_for_stmt (stmt);
 729
 730   result = create_tmp_var (optype, "PROF");
 731   tmp2 = create_tmp_var (optype, "PROF");
 732   tmp3 = create_tmp_var (optype, "PROF");
 733   stmt2 = gimple_build_assign_with_ops (PLUS_EXPR, tmp2, op2,
 734                                         build_int_cst (optype, -1));
 735   stmt3 = gimple_build_assign_with_ops (BIT_AND_EXPR, tmp3, tmp2, op2);
 736   stmt4 = gimple_build_cond (NE_EXPR, tmp3, build_int_cst (optype, 0),
 737                              NULL_TREE, NULL_TREE);
 738   gsi_insert_before (&gsi, stmt2, GSI_SAME_STMT);
 739   gsi_insert_before (&gsi, stmt3, GSI_SAME_STMT);
 740   gsi_insert_before (&gsi, stmt4, GSI_SAME_STMT);
 741   bb1end = stmt4;
 742
 743   /* tmp2 == op2-1 inherited from previous block.  */
 744   stmt1 = gimple_build_assign_with_ops (BIT_AND_EXPR, result, op1, tmp2);
 745   gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
 746   bb2end = stmt1;
 747
 748   stmt1 = gimple_build_assign_with_ops (gimple_assign_rhs_code (stmt), result,
 749                                         op1, op2);
 750   gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
 751   bb3end = stmt1;
 752
 753   /* Fix CFG. */
 754   /* Edge e23 connects bb2 to bb3, etc. */
 755   e12 = split_block (bb, bb1end);
 756   bb2 = e12->dest;
 757   bb2->count = count;
 758   e23 = split_block (bb2, bb2end);
 759   bb3 = e23->dest;
 760   bb3->count = all - count;
 761   e34 = split_block (bb3, bb3end);
 762   bb4 = e34->dest;
 763   bb4->count = all;
 764
 765   e12->flags &= ~EDGE_FALLTHRU;
 766   e12->flags |= EDGE_FALSE_VALUE;
 767   e12->probability = prob;
 768   e12->count = count;
 769
 770   e13 = make_edge (bb, bb3, EDGE_TRUE_VALUE);
 771   e13->probability = REG_BR_PROB_BASE - prob;
 772   e13->count = all - count;
 773
 774   remove_edge (e23);
 775
 776   e24 = make_edge (bb2, bb4, EDGE_FALLTHRU);
 777   e24->probability = REG_BR_PROB_BASE;
 778   e24->count = count;
 779
 780   e34->probability = REG_BR_PROB_BASE;
 781   e34->count = all - count;
 782
 783   return result;
 784 }
 785
 786 /* Do transform 2) on INSN if applicable.  */
 787 static bool
 788 gimple_mod_pow2_value_transform (gimple_stmt_iterator *si)
 789 {
 790   histogram_value histogram;
 791   enum tree_code code;
 792   gcov_type count, wrong_values, all;
 793   tree lhs_type, result, value;
 794   gcov_type prob;
 795   gimple stmt;
 796
 797   stmt = gsi_stmt (*si);
 798   if (gimple_code (stmt) != GIMPLE_ASSIGN)
 799     return false;
 800
 801   lhs_type = TREE_TYPE (gimple_assign_lhs (stmt));
 802   if (!INTEGRAL_TYPE_P (lhs_type))
 803     return false;
 804
 805   code = gimple_assign_rhs_code (stmt);
 806
 807   if (code != TRUNC_MOD_EXPR || !TYPE_UNSIGNED (lhs_type))
 808     return false;
 809
 810   histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_POW2);
 811   if (!histogram)
 812     return false;
 813
 814   value = histogram->hvalue.value;
 815   wrong_values = histogram->hvalue.counters[0];
 816   count = histogram->hvalue.counters[1];
 817
 818   gimple_remove_histogram_value (cfun, stmt, histogram);
 819
 820   /* We require that we hit a power of 2 at least half of all evaluations.  */
 821   if (simple_cst_equal (gimple_assign_rhs2 (stmt), value) != 1
 822       || count < wrong_values
 823       || optimize_bb_for_size_p (gimple_bb (stmt)))
 824     return false;
 825
 826   if (dump_file)
 827     {
 828       fprintf (dump_file, "Mod power of 2 transformation on insn ");
 829       print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM);
 830     }
 831
 832   /* Compute probability of taking the optimal path.  */
 833   all = count + wrong_values;
 834
 835   if (check_counter (stmt, "pow2", &count, &all, gimple_bb (stmt)->count))
 836     return false;
 837
 838   if (all > 0)
 839     prob = (count * REG_BR_PROB_BASE + all / 2) / all;
 840   else
 841     prob = 0;
 842
 843   result = gimple_mod_pow2 (stmt, prob, count, all);
 844
 845   gimple_assign_set_rhs_from_tree (si, result);
 846
 847   return true;
 848 }
 849
 850 /* Generate code for transformations 3 and 4 (with parent gimple assign STMT, and
 851    NCOUNTS the number of cases to support.  Currently only NCOUNTS==0 or 1 is
 852    supported and this is built into this interface.  The probabilities of taking
 853    the optimal paths are PROB1 and PROB2, which are equivalent to COUNT1/ALL and
 854    COUNT2/ALL respectively within roundoff error).  This generates the
 855    result into a temp and returns the temp; it does not replace or alter
 856    the original STMT.  */
 857 /* FIXME: Generalize the interface to handle NCOUNTS > 1.  */
 858
 859 static tree
 860 gimple_mod_subtract (gimple stmt, int prob1, int prob2, int ncounts,
 861                      gcov_type count1, gcov_type count2, gcov_type all)
 862 {
 863   gimple stmt1, stmt2, stmt3;
 864   tree tmp1;
 865   gimple bb1end, bb2end = NULL, bb3end;
 866   basic_block bb, bb2, bb3, bb4;
 867   tree optype, op1, op2;
 868   edge e12, e23 = 0, e24, e34, e14;
 869   gimple_stmt_iterator gsi;
 870   tree result;
 871
 872   gcc_assert (is_gimple_assign (stmt)
 873               && gimple_assign_rhs_code (stmt) == TRUNC_MOD_EXPR);
 874
 875   optype = TREE_TYPE (gimple_assign_lhs (stmt));
 876   op1 = gimple_assign_rhs1 (stmt);
 877   op2 = gimple_assign_rhs2 (stmt);
 878
 879   bb = gimple_bb (stmt);
 880   gsi = gsi_for_stmt (stmt);
 881
 882   result = create_tmp_var (optype, "PROF");
 883   tmp1 = create_tmp_var (optype, "PROF");
 884   stmt1 = gimple_build_assign (result, op1);
 885   stmt2 = gimple_build_assign (tmp1, op2);
 886   stmt3 = gimple_build_cond (LT_EXPR, result, tmp1, NULL_TREE, NULL_TREE);
 887   gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
 888   gsi_insert_before (&gsi, stmt2, GSI_SAME_STMT);
 889   gsi_insert_before (&gsi, stmt3, GSI_SAME_STMT);
 890   bb1end = stmt3;
 891
 892   if (ncounts)  /* Assumed to be 0 or 1 */
 893     {
 894       stmt1 = gimple_build_assign_with_ops (MINUS_EXPR, result, result, tmp1);
 895       stmt2 = gimple_build_cond (LT_EXPR, result, tmp1, NULL_TREE, NULL_TREE);
 896       gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
 897       gsi_insert_before (&gsi, stmt2, GSI_SAME_STMT);
 898       bb2end = stmt2;
 899     }
 900
 901   /* Fallback case. */
 902   stmt1 = gimple_build_assign_with_ops (gimple_assign_rhs_code (stmt), result,
 903                                         result, tmp1);
 904   gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
 905   bb3end = stmt1;
 906
 907   /* Fix CFG. */
 908   /* Edge e23 connects bb2 to bb3, etc. */
 909   /* However block 3 is optional; if it is not there, references
 910      to 3 really refer to block 2. */
 911   e12 = split_block (bb, bb1end);
 912   bb2 = e12->dest;
 913   bb2->count = all - count1;
 914
 915   if (ncounts)  /* Assumed to be 0 or 1.  */
 916     {
 917       e23 = split_block (bb2, bb2end);
 918       bb3 = e23->dest;
 919       bb3->count = all - count1 - count2;
 920     }
 921
 922   e34 = split_block (ncounts ? bb3 : bb2, bb3end);
 923   bb4 = e34->dest;
 924   bb4->count = all;
 925
 926   e12->flags &= ~EDGE_FALLTHRU;
 927   e12->flags |= EDGE_FALSE_VALUE;
 928   e12->probability = REG_BR_PROB_BASE - prob1;
 929   e12->count = all - count1;
 930
 931   e14 = make_edge (bb, bb4, EDGE_TRUE_VALUE);
 932   e14->probability = prob1;
 933   e14->count = count1;
 934
 935   if (ncounts)  /* Assumed to be 0 or 1.  */
 936     {
 937       e23->flags &= ~EDGE_FALLTHRU;
 938       e23->flags |= EDGE_FALSE_VALUE;
 939       e23->count = all - count1 - count2;
 940       e23->probability = REG_BR_PROB_BASE - prob2;
 941
 942       e24 = make_edge (bb2, bb4, EDGE_TRUE_VALUE);
 943       e24->probability = prob2;
 944       e24->count = count2;
 945     }
 946
 947   e34->probability = REG_BR_PROB_BASE;
 948   e34->count = all - count1 - count2;
 949
 950   return result;
 951 }
 952
 953
 954 /* Do transforms 3) and 4) on the statement pointed-to by SI if applicable.  */
 955
 956 static bool
 957 gimple_mod_subtract_transform (gimple_stmt_iterator *si)
 958 {
 959   histogram_value histogram;
 960   enum tree_code code;
 961   gcov_type count, wrong_values, all;
 962   tree lhs_type, result, value;
 963   gcov_type prob1, prob2;
 964   unsigned int i, steps;
 965   gcov_type count1, count2;
 966   gimple stmt;
 967
 968   stmt = gsi_stmt (*si);
 969   if (gimple_code (stmt) != GIMPLE_ASSIGN)
 970     return false;
 971
 972   lhs_type = TREE_TYPE (gimple_assign_lhs (stmt));
 973   if (!INTEGRAL_TYPE_P (lhs_type))
 974     return false;
 975
 976   code = gimple_assign_rhs_code (stmt);
 977
 978   if (code != TRUNC_MOD_EXPR || !TYPE_UNSIGNED (lhs_type))
 979     return false;
 980
 981   histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_INTERVAL);
 982   if (!histogram)
 983     return false;
 984
 985   value = histogram->hvalue.value;
 986   all = 0;
 987   wrong_values = 0;
 988   for (i = 0; i < histogram->hdata.intvl.steps; i++)
 989     all += histogram->hvalue.counters[i];
 990
 991   wrong_values += histogram->hvalue.counters[i];
 992   wrong_values += histogram->hvalue.counters[i+1];
 993   steps = histogram->hdata.intvl.steps;
 994   all += wrong_values;
 995   count1 = histogram->hvalue.counters[0];
 996   count2 = histogram->hvalue.counters[1];
 997
 998   /* Compute probability of taking the optimal path.  */
 999   if (check_counter (stmt, "interval", &count1, &all, gimple_bb (stmt)->count))
1000     {
1001       gimple_remove_histogram_value (cfun, stmt, histogram);
1002       return false;
1003     }
1004
1005   if (flag_profile_correction && count1 + count2 > all)
1006       all = count1 + count2;
1007
1008   gcc_assert (count1 + count2 <= all);
1009
1010   /* We require that we use just subtractions in at least 50% of all
1011      evaluations.  */
1012   count = 0;
1013   for (i = 0; i < histogram->hdata.intvl.steps; i++)
1014     {
1015       count += histogram->hvalue.counters[i];
1016       if (count * 2 >= all)
1017         break;
1018     }
1019   if (i == steps
1020       || optimize_bb_for_size_p (gimple_bb (stmt)))
1021     return false;
1022
1023   gimple_remove_histogram_value (cfun, stmt, histogram);
1024   if (dump_file)
1025     {
1026       fprintf (dump_file, "Mod subtract transformation on insn ");
1027       print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM);
1028     }
1029
1030   /* Compute probability of taking the optimal path(s).  */
1031   if (all > 0)
1032     {
1033       prob1 = (count1 * REG_BR_PROB_BASE + all / 2) / all;
1034       prob2 = (count2 * REG_BR_PROB_BASE + all / 2) / all;
1035     }
1036   else
1037     {
1038       prob1 = prob2 = 0;
1039     }
1040
1041   /* In practice, "steps" is always 2.  This interface reflects this,
1042      and will need to be changed if "steps" can change.  */
1043   result = gimple_mod_subtract (stmt, prob1, prob2, i, count1, count2, all);
1044
1045   gimple_assign_set_rhs_from_tree (si, result);
1046
1047   return true;
1048 }
1049
1050 static struct cgraph_node** pid_map = NULL;
1051
1052 /* Initialize map of pids (pid -> cgraph node) */
1053
1054 static void
1055 init_pid_map (void)
1056 {
1057   struct cgraph_node *n;
1058
1059   if (pid_map != NULL)
1060     return;
1061
1062   pid_map
1063     = (struct cgraph_node**) xmalloc (sizeof (struct cgraph_node*) * cgraph_max_pid);
1064
1065   for (n = cgraph_nodes; n; n = n->next)
1066     {
1067       if (n->pid != -1)
1068         pid_map [n->pid] = n;
1069     }
1070 }
1071
1072 /* Return cgraph node for function with pid */
1073
1074 static inline struct cgraph_node*
1075 find_func_by_pid (int   pid)
1076 {
1077   init_pid_map ();
1078
1079   return pid_map [pid];
1080 }
1081
1082 /* Do transformation
1083
1084   if (actual_callee_address == address_of_most_common_function/method)
1085     do direct call
1086   else
1087     old call
1088  */
1089
1090 static gimple
1091 gimple_ic (gimple stmt, gimple call, struct cgraph_node *direct_call,
1092            int prob, gcov_type count, gcov_type all)
1093 {
1094   gimple stmt1, stmt2, stmt3;
1095   tree tmp1, tmpv, tmp;
1096   gimple bb1end, bb2end, bb3end;
1097   basic_block bb, bb2, bb3, bb4;
1098   tree optype = build_pointer_type (void_type_node);
1099   edge e12, e13, e23, e24, e34;
1100   gimple_stmt_iterator gsi;
1101   int region;
1102
1103   bb = gimple_bb (stmt);
1104   gsi = gsi_for_stmt (stmt);
1105
1106   tmpv = create_tmp_var (optype, "PROF");
1107   tmp1 = create_tmp_var (optype, "PROF");
1108   stmt1 = gimple_build_assign (tmpv, unshare_expr (gimple_call_fn (call)));
1109
1110   tmp = fold_convert (optype, build_addr (direct_call->decl,
1111                                           current_function_decl));
1112   stmt2 = gimple_build_assign (tmp1, tmp);
1113   stmt3 = gimple_build_cond (NE_EXPR, tmp1, tmpv, NULL_TREE, NULL_TREE);
1114   gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
1115   gsi_insert_before (&gsi, stmt2, GSI_SAME_STMT);
1116   gsi_insert_before (&gsi, stmt3, GSI_SAME_STMT);
1117   bb1end = stmt3;
1118
1119   stmt1 = gimple_copy (stmt);
1120   gimple_call_set_fndecl (stmt1, direct_call->decl);
1121   gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
1122   bb2end = stmt1;
1123   bb3end = stmt;
1124
1125   /* Fix CFG. */
1126   /* Edge e23 connects bb2 to bb3, etc. */
1127   e12 = split_block (bb, bb1end);
1128   bb2 = e12->dest;
1129   bb2->count = count;
1130   e23 = split_block (bb2, bb2end);
1131   bb3 = e23->dest;
1132   bb3->count = all - count;
1133   e34 = split_block (bb3, bb3end);
1134   bb4 = e34->dest;
1135   bb4->count = all;
1136
1137   e12->flags &= ~EDGE_FALLTHRU;
1138   e12->flags |= EDGE_FALSE_VALUE;
1139   e12->probability = prob;
1140   e12->count = count;
1141
1142   e13 = make_edge (bb, bb3, EDGE_TRUE_VALUE);
1143   e13->probability = REG_BR_PROB_BASE - prob;
1144   e13->count = all - count;
1145
1146   remove_edge (e23);
1147
1148   e24 = make_edge (bb2, bb4, EDGE_FALLTHRU);
1149   e24->probability = REG_BR_PROB_BASE;
1150   e24->count = count;
1151   e34->probability = REG_BR_PROB_BASE;
1152   e34->count = all - count;
1153
1154   /* Fix eh edges */
1155   region = lookup_stmt_eh_region (stmt);
1156   if (region >= 0 && stmt_could_throw_p (stmt1))
1157     {
1158       add_stmt_to_eh_region (stmt1, region);
1159       make_eh_edges (stmt1);
1160     }
1161
1162   if (region >= 0 && stmt_could_throw_p (stmt))
1163     {
1164       gimple_purge_dead_eh_edges (bb4);
1165       make_eh_edges (stmt);
1166     }
1167
1168   return stmt1;
1169 }
1170
1171 /*
1172   For every checked indirect/virtual call determine if most common pid of
1173   function/class method has probability more than 50%. If yes modify code of
1174   this call to:
1175  */
1176
1177 static bool
1178 gimple_ic_transform (gimple stmt)
1179 {
1180   histogram_value histogram;
1181   gcov_type val, count, all, bb_all;
1182   gcov_type prob;
1183   tree callee;
1184   gimple modify;
1185   struct cgraph_node *direct_call;
1186
1187   if (gimple_code (stmt) != GIMPLE_CALL)
1188     return false;
1189
1190   callee = gimple_call_fn (stmt);
1191
1192   if (TREE_CODE (callee) == FUNCTION_DECL)
1193     return false;
1194
1195   histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_INDIR_CALL);
1196   if (!histogram)
1197     return false;
1198
1199   val = histogram->hvalue.counters [0];
1200   count = histogram->hvalue.counters [1];
1201   all = histogram->hvalue.counters [2];
1202   gimple_remove_histogram_value (cfun, stmt, histogram);
1203
1204   if (4 * count <= 3 * all)
1205     return false;
1206
1207   bb_all = gimple_bb (stmt)->count;
1208   /* The order of CHECK_COUNTER calls is important -
1209      since check_counter can correct the third parameter
1210      and we want to make count <= all <= bb_all. */
1211   if ( check_counter (stmt, "ic", &all, &bb_all, bb_all)
1212       || check_counter (stmt, "ic", &count, &all, all))
1213     return false;
1214
1215   if (all > 0)
1216     prob = (count * REG_BR_PROB_BASE + all / 2) / all;
1217   else
1218     prob = 0;
1219   direct_call = find_func_by_pid ((int)val);
1220
1221   if (direct_call == NULL)
1222     return false;
1223
1224   modify = gimple_ic (stmt, stmt, direct_call, prob, count, all);
1225
1226   if (dump_file)
1227     {
1228       fprintf (dump_file, "Indirect call -> direct call ");
1229       print_generic_expr (dump_file, gimple_call_fn (stmt), TDF_SLIM);
1230       fprintf (dump_file, "=> ");
1231       print_generic_expr (dump_file, direct_call->decl, TDF_SLIM);
1232       fprintf (dump_file, " transformation on insn ");
1233       print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM);
1234       fprintf (dump_file, " to ");
1235       print_gimple_stmt (dump_file, modify, 0, TDF_SLIM);
1236       fprintf (dump_file, "hist->count "HOST_WIDEST_INT_PRINT_DEC
1237                " hist->all "HOST_WIDEST_INT_PRINT_DEC"\n", count, all);
1238     }
1239
1240   return true;
1241 }
1242
1243 /* Return true if the stringop CALL with FNDECL shall be profiled.  */
1244 static bool
1245 interesting_stringop_to_profile_p (tree fndecl, gimple call)
1246 {
1247   enum built_in_function fcode = DECL_FUNCTION_CODE (fndecl);
1248
1249   if (fcode != BUILT_IN_MEMCPY && fcode != BUILT_IN_MEMPCPY
1250       && fcode != BUILT_IN_MEMSET && fcode != BUILT_IN_BZERO)
1251     return false;
1252
1253   switch (fcode)
1254     {
1255      case BUILT_IN_MEMCPY:
1256      case BUILT_IN_MEMPCPY:
1257        return validate_gimple_arglist (call, POINTER_TYPE, POINTER_TYPE,
1258                                        INTEGER_TYPE, VOID_TYPE);
1259      case BUILT_IN_MEMSET:
1260        return validate_gimple_arglist (call, POINTER_TYPE, INTEGER_TYPE,
1261                                       INTEGER_TYPE, VOID_TYPE);
1262      case BUILT_IN_BZERO:
1263        return validate_gimple_arglist (call, POINTER_TYPE, INTEGER_TYPE,
1264                                        VOID_TYPE);
1265      default:
1266        gcc_unreachable ();
1267     }
1268 }
1269
1270 /* Convert   stringop (..., size)
1271    into
1272    if (size == VALUE)
1273      stringop (...., VALUE);
1274    else
1275      stringop (...., size);
1276    assuming constant propagation of VALUE will happen later.
1277 */
1278 static void
1279 gimple_stringop_fixed_value (gimple stmt, tree value, int prob, gcov_type count,
1280                            gcov_type all)
1281 {
1282   gimple stmt1, stmt2, stmt3;
1283   tree tmp1, tmpv;
1284   gimple bb1end, bb2end;
1285   basic_block bb, bb2, bb3, bb4;
1286   edge e12, e13, e23, e24, e34;
1287   gimple_stmt_iterator gsi;
1288   tree blck_size = gimple_call_arg (stmt, 2);
1289   tree optype = TREE_TYPE (blck_size);
1290   int region;
1291
1292   bb = gimple_bb (stmt);
1293   gsi = gsi_for_stmt (stmt);
1294
1295   if (gsi_end_p (gsi))
1296     {
1297       edge_iterator ei;
1298       for (ei = ei_start (bb->succs); (e34 = ei_safe_edge (ei)); )
1299         if (!(e34->flags & EDGE_ABNORMAL))
1300           break;
1301     }
1302   else
1303     {
1304       e34 = split_block (bb, stmt);
1305       gsi = gsi_for_stmt (stmt);
1306     }
1307   bb4 = e34->dest;
1308
1309   tmpv = create_tmp_var (optype, "PROF");
1310   tmp1 = create_tmp_var (optype, "PROF");
1311   stmt1 = gimple_build_assign (tmpv, fold_convert (optype, value));
1312   stmt2 = gimple_build_assign (tmp1, blck_size);
1313   stmt3 = gimple_build_cond (NE_EXPR, tmp1, tmpv, NULL_TREE, NULL_TREE);
1314   gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
1315   gsi_insert_before (&gsi, stmt2, GSI_SAME_STMT);
1316   gsi_insert_before (&gsi, stmt3, GSI_SAME_STMT);
1317   bb1end = stmt3;
1318
1319   stmt1 = gimple_copy (stmt);
1320   gimple_call_set_arg (stmt1, 2, value);
1321   gsi_insert_before (&gsi, stmt1, GSI_SAME_STMT);
1322   region = lookup_stmt_eh_region (stmt);
1323   if (region >= 0)
1324     add_stmt_to_eh_region (stmt1, region);
1325   bb2end = stmt1;
1326
1327   /* Fix CFG. */
1328   /* Edge e23 connects bb2 to bb3, etc. */
1329   e12 = split_block (bb, bb1end);
1330   bb2 = e12->dest;
1331   bb2->count = count;
1332   e23 = split_block (bb2, bb2end);
1333   bb3 = e23->dest;
1334   bb3->count = all - count;
1335
1336   e12->flags &= ~EDGE_FALLTHRU;
1337   e12->flags |= EDGE_FALSE_VALUE;
1338   e12->probability = prob;
1339   e12->count = count;
1340
1341   e13 = make_edge (bb, bb3, EDGE_TRUE_VALUE);
1342   e13->probability = REG_BR_PROB_BASE - prob;
1343   e13->count = all - count;
1344
1345   remove_edge (e23);
1346
1347   e24 = make_edge (bb2, bb4, EDGE_FALLTHRU);
1348   e24->probability = REG_BR_PROB_BASE;
1349   e24->count = count;
1350
1351   e34->probability = REG_BR_PROB_BASE;
1352   e34->count = all - count;
1353 }
1354
1355 /* Find values inside STMT for that we want to measure histograms for
1356    division/modulo optimization.  */
1357 static bool
1358 gimple_stringops_transform (gimple_stmt_iterator *gsi)
1359 {
1360   gimple stmt = gsi_stmt (*gsi);
1361   tree fndecl;
1362   tree blck_size;
1363   enum built_in_function fcode;
1364   histogram_value histogram;
1365   gcov_type count, all, val;
1366   tree value;
1367   tree dest, src;
1368   unsigned int dest_align, src_align;
1369   gcov_type prob;
1370   tree tree_val;
1371
1372   if (gimple_code (stmt) != GIMPLE_CALL)
1373     return false;
1374   fndecl = gimple_call_fndecl (stmt);
1375   if (!fndecl)
1376     return false;
1377   fcode = DECL_FUNCTION_CODE (fndecl);
1378   if (!interesting_stringop_to_profile_p (fndecl, stmt))
1379     return false;
1380
1381   if (fcode == BUILT_IN_BZERO)
1382     blck_size = gimple_call_arg (stmt, 1);
1383   else
1384     blck_size = gimple_call_arg (stmt, 2);
1385   if (TREE_CODE (blck_size) == INTEGER_CST)
1386     return false;
1387
1388   histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_SINGLE_VALUE);
1389   if (!histogram)
1390     return false;
1391   value = histogram->hvalue.value;
1392   val = histogram->hvalue.counters[0];
1393   count = histogram->hvalue.counters[1];
1394   all = histogram->hvalue.counters[2];
1395   gimple_remove_histogram_value (cfun, stmt, histogram);
1396   /* We require that count is at least half of all; this means
1397      that for the transformation to fire the value must be constant
1398      at least 80% of time.  */
1399   if ((6 * count / 5) < all || optimize_bb_for_size_p (gimple_bb (stmt)))
1400     return false;
1401   if (check_counter (stmt, "value", &count, &all, gimple_bb (stmt)->count))
1402     return false;
1403   if (all > 0)
1404     prob = (count * REG_BR_PROB_BASE + all / 2) / all;
1405   else
1406     prob = 0;
1407   dest = gimple_call_arg (stmt, 0);
1408   dest_align = get_pointer_alignment (dest, BIGGEST_ALIGNMENT);
1409   switch (fcode)
1410     {
1411     case BUILT_IN_MEMCPY:
1412     case BUILT_IN_MEMPCPY:
1413       src = gimple_call_arg (stmt, 1);
1414       src_align = get_pointer_alignment (src, BIGGEST_ALIGNMENT);
1415       if (!can_move_by_pieces (val, MIN (dest_align, src_align)))
1416         return false;
1417       break;
1418     case BUILT_IN_MEMSET:
1419       if (!can_store_by_pieces (val, builtin_memset_read_str,
1420                                 gimple_call_arg (stmt, 1),
1421                                 dest_align, true))
1422         return false;
1423       break;
1424     case BUILT_IN_BZERO:
1425       if (!can_store_by_pieces (val, builtin_memset_read_str,
1426                                 integer_zero_node,
1427                                 dest_align, true))
1428         return false;
1429       break;
1430     default:
1431       gcc_unreachable ();
1432     }
1433   tree_val = build_int_cst_wide (get_gcov_type (),
1434                                  (unsigned HOST_WIDE_INT) val,
1435                                  val >> (HOST_BITS_PER_WIDE_INT - 1) >> 1);
1436   if (dump_file)
1437     {
1438       fprintf (dump_file, "Single value %i stringop transformation on ",
1439                (int)val);
1440       print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM);
1441     }
1442   gimple_stringop_fixed_value (stmt, tree_val, prob, count, all);
1443
1444   return true;
1445 }
1446
1447 void
1448 stringop_block_profile (gimple stmt, unsigned int *expected_align,
1449                         HOST_WIDE_INT *expected_size)
1450 {
1451   histogram_value histogram;
1452   histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_AVERAGE);
1453   if (!histogram)
1454     *expected_size = -1;
1455   else if (!histogram->hvalue.counters[1])
1456     {
1457       *expected_size = -1;
1458       gimple_remove_histogram_value (cfun, stmt, histogram);
1459     }
1460   else
1461     {
1462       gcov_type size;
1463       size = ((histogram->hvalue.counters[0]
1464               + histogram->hvalue.counters[1] / 2)
1465                / histogram->hvalue.counters[1]);
1466       /* Even if we can hold bigger value in SIZE, INT_MAX
1467          is safe "infinity" for code generation strategies.  */
1468       if (size > INT_MAX)
1469         size = INT_MAX;
1470       *expected_size = size;
1471       gimple_remove_histogram_value (cfun, stmt, histogram);
1472     }
1473   histogram = gimple_histogram_value_of_type (cfun, stmt, HIST_TYPE_IOR);
1474   if (!histogram)
1475     *expected_align = 0;
1476   else if (!histogram->hvalue.counters[0])
1477     {
1478       gimple_remove_histogram_value (cfun, stmt, histogram);
1479       *expected_align = 0;
1480     }
1481   else
1482     {
1483       gcov_type count;
1484       int alignment;
1485
1486       count = histogram->hvalue.counters[0];
1487       alignment = 1;
1488       while (!(count & alignment)
1489              && (alignment * 2 * BITS_PER_UNIT))
1490         alignment <<= 1;
1491       *expected_align = alignment * BITS_PER_UNIT;
1492       gimple_remove_histogram_value (cfun, stmt, histogram);
1493     }
1494 }
1495
1496 struct value_prof_hooks {
1497   /* Find list of values for which we want to measure histograms.  */
1498   void (*find_values_to_profile) (histogram_values *);
1499
1500   /* Identify and exploit properties of values that are hard to analyze
1501      statically.  See value-prof.c for more detail.  */
1502   bool (*value_profile_transformations) (void);
1503 };
1504 \f
1505 /* Find values inside STMT for that we want to measure histograms for
1506    division/modulo optimization.  */
1507 static void
1508 gimple_divmod_values_to_profile (gimple stmt, histogram_values *values)
1509 {
1510   tree lhs, divisor, op0, type;
1511   histogram_value hist;
1512
1513   if (gimple_code (stmt) != GIMPLE_ASSIGN)
1514     return;
1515
1516   lhs = gimple_assign_lhs (stmt);
1517   type = TREE_TYPE (lhs);
1518   if (!INTEGRAL_TYPE_P (type))
1519     return;
1520
1521   switch (gimple_assign_rhs_code (stmt))
1522     {
1523     case TRUNC_DIV_EXPR:
1524     case TRUNC_MOD_EXPR:
1525       divisor = gimple_assign_rhs2 (stmt);
1526       op0 = gimple_assign_rhs1 (stmt);
1527
1528       VEC_reserve (histogram_value, heap, *values, 3);
1529
1530       if (is_gimple_reg (divisor))
1531         /* Check for the case where the divisor is the same value most
1532            of the time.  */
1533         VEC_quick_push (histogram_value, *values,
1534                         gimple_alloc_histogram_value (cfun,
1535                                                       HIST_TYPE_SINGLE_VALUE,
1536                                                       stmt, divisor));
1537
1538       /* For mod, check whether it is not often a noop (or replaceable by
1539          a few subtractions).  */
1540       if (gimple_assign_rhs_code (stmt) == TRUNC_MOD_EXPR
1541           && TYPE_UNSIGNED (type))
1542         {
1543           tree val;
1544           /* Check for a special case where the divisor is power of 2.  */
1545           VEC_quick_push (histogram_value, *values,
1546                           gimple_alloc_histogram_value (cfun, HIST_TYPE_POW2,
1547                                                         stmt, divisor));
1548
1549           val = build2 (TRUNC_DIV_EXPR, type, op0, divisor);
1550           hist = gimple_alloc_histogram_value (cfun, HIST_TYPE_INTERVAL,
1551                                                stmt, val);
1552           hist->hdata.intvl.int_start = 0;
1553           hist->hdata.intvl.steps = 2;
1554           VEC_quick_push (histogram_value, *values, hist);
1555         }
1556       return;
1557
1558     default:
1559       return;
1560     }
1561 }
1562
1563 /* Find calls inside STMT for that we want to measure histograms for
1564    indirect/virtual call optimization. */
1565
1566 static void
1567 gimple_indirect_call_to_profile (gimple stmt, histogram_values *values)
1568 {
1569   tree callee;
1570
1571   if (gimple_code (stmt) != GIMPLE_CALL
1572       || gimple_call_fndecl (stmt) != NULL_TREE)
1573     return;
1574
1575   callee = gimple_call_fn (stmt);
1576
1577   VEC_reserve (histogram_value, heap, *values, 3);
1578
1579   VEC_quick_push (histogram_value, *values,
1580                   gimple_alloc_histogram_value (cfun, HIST_TYPE_INDIR_CALL,
1581                                                 stmt, callee));
1582
1583   return;
1584 }
1585
1586 /* Find values inside STMT for that we want to measure histograms for
1587    string operations.  */
1588 static void
1589 gimple_stringops_values_to_profile (gimple stmt, histogram_values *values)
1590 {
1591   tree fndecl;
1592   tree blck_size;
1593   tree dest;
1594   enum built_in_function fcode;
1595
1596   if (gimple_code (stmt) != GIMPLE_CALL)
1597     return;
1598   fndecl = gimple_call_fndecl (stmt);
1599   if (!fndecl)
1600     return;
1601   fcode = DECL_FUNCTION_CODE (fndecl);
1602
1603   if (!interesting_stringop_to_profile_p (fndecl, stmt))
1604     return;
1605
1606   dest = gimple_call_arg (stmt, 0);
1607   if (fcode == BUILT_IN_BZERO)
1608     blck_size = gimple_call_arg (stmt, 1);
1609   else
1610     blck_size = gimple_call_arg (stmt, 2);
1611
1612   if (TREE_CODE (blck_size) != INTEGER_CST)
1613     {
1614       VEC_safe_push (histogram_value, heap, *values,
1615                      gimple_alloc_histogram_value (cfun, HIST_TYPE_SINGLE_VALUE,
1616                                                    stmt, blck_size));
1617       VEC_safe_push (histogram_value, heap, *values,
1618                      gimple_alloc_histogram_value (cfun, HIST_TYPE_AVERAGE,
1619                                                    stmt, blck_size));
1620     }
1621   if (TREE_CODE (blck_size) != INTEGER_CST)
1622     VEC_safe_push (histogram_value, heap, *values,
1623                    gimple_alloc_histogram_value (cfun, HIST_TYPE_IOR,
1624                                                  stmt, dest));
1625 }
1626
1627 /* Find values inside STMT for that we want to measure histograms and adds
1628    them to list VALUES.  */
1629
1630 static void
1631 gimple_values_to_profile (gimple stmt, histogram_values *values)
1632 {
1633   if (flag_value_profile_transformations)
1634     {
1635       gimple_divmod_values_to_profile (stmt, values);
1636       gimple_stringops_values_to_profile (stmt, values);
1637       gimple_indirect_call_to_profile (stmt, values);
1638     }
1639 }
1640
1641 static void
1642 gimple_find_values_to_profile (histogram_values *values)
1643 {
1644   basic_block bb;
1645   gimple_stmt_iterator gsi;
1646   unsigned i;
1647   histogram_value hist = NULL;
1648
1649   *values = NULL;
1650   FOR_EACH_BB (bb)
1651     for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
1652       gimple_values_to_profile (gsi_stmt (gsi), values);
1653
1654   for (i = 0; VEC_iterate (histogram_value, *values, i, hist); i++)
1655     {
1656       switch (hist->type)
1657         {
1658         case HIST_TYPE_INTERVAL:
1659           hist->n_counters = hist->hdata.intvl.steps + 2;
1660           break;
1661
1662         case HIST_TYPE_POW2:
1663           hist->n_counters = 2;
1664           break;
1665
1666         case HIST_TYPE_SINGLE_VALUE:
1667           hist->n_counters = 3;
1668           break;
1669
1670         case HIST_TYPE_CONST_DELTA:
1671           hist->n_counters = 4;
1672           break;
1673
1674         case HIST_TYPE_INDIR_CALL:
1675           hist->n_counters = 3;
1676           break;
1677
1678         case HIST_TYPE_AVERAGE:
1679           hist->n_counters = 2;
1680           break;
1681
1682         case HIST_TYPE_IOR:
1683           hist->n_counters = 1;
1684           break;
1685
1686         default:
1687           gcc_unreachable ();
1688         }
1689       if (dump_file)
1690         {
1691           fprintf (dump_file, "Stmt ");
1692           print_gimple_stmt (dump_file, hist->hvalue.stmt, 0, TDF_SLIM);
1693           dump_histogram_value (dump_file, hist);
1694         }
1695     }
1696 }
1697
1698 static struct value_prof_hooks gimple_value_prof_hooks = {
1699   gimple_find_values_to_profile,
1700   gimple_value_profile_transformations
1701 };
1702
1703 void
1704 gimple_register_value_prof_hooks (void)
1705 {
1706   gcc_assert (current_ir_type () == IR_GIMPLE);
1707   value_prof_hooks = &gimple_value_prof_hooks;
1708 }
1709 \f
1710 /* IR-independent entry points.  */
1711 void
1712 find_values_to_profile (histogram_values *values)
1713 {
1714   (value_prof_hooks->find_values_to_profile) (values);
1715 }
1716
1717 bool
1718 value_profile_transformations (void)
1719 {
1720   return (value_prof_hooks->value_profile_transformations) ();
1721 }
1722 \f