gcc/tree-vectorizer.c

   1 /* Vectorizer
   2    Copyright (C) 2003-2015 Free Software Foundation, Inc.
   3    Contributed by Dorit Naishlos <dorit@il.ibm.com>
   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 /* Loop and basic block vectorizer.
  22
  23   This file contains drivers for the three vectorizers:
  24   (1) loop vectorizer (inter-iteration parallelism),
  25   (2) loop-aware SLP (intra-iteration parallelism) (invoked by the loop
  26       vectorizer)
  27   (3) BB vectorizer (out-of-loops), aka SLP
  28
  29   The rest of the vectorizer's code is organized as follows:
  30   - tree-vect-loop.c - loop specific parts such as reductions, etc. These are
  31     used by drivers (1) and (2).
  32   - tree-vect-loop-manip.c - vectorizer's loop control-flow utilities, used by
  33     drivers (1) and (2).
  34   - tree-vect-slp.c - BB vectorization specific analysis and transformation,
  35     used by drivers (2) and (3).
  36   - tree-vect-stmts.c - statements analysis and transformation (used by all).
  37   - tree-vect-data-refs.c - vectorizer specific data-refs analysis and
  38     manipulations (used by all).
  39   - tree-vect-patterns.c - vectorizable code patterns detector (used by all)
  40
  41   Here's a poor attempt at illustrating that:
  42
  43      tree-vectorizer.c:
  44      loop_vect()  loop_aware_slp()  slp_vect()
  45           |        /           \          /
  46           |       /             \        /
  47           tree-vect-loop.c  tree-vect-slp.c
  48                 | \      \  /      /   |
  49                 |  \      \/      /    |
  50                 |   \     /\     /     |
  51                 |    \   /  \   /      |
  52          tree-vect-stmts.c  tree-vect-data-refs.c
  53                        \      /
  54                     tree-vect-patterns.c
  55 */
  56
  57 #include "config.h"
  58 #include "system.h"
  59 #include "coretypes.h"
  60 #include "dumpfile.h"
  61 #include "tm.h"
  62 #include "hash-set.h"
  63 #include "vec.h"
  64 #include "input.h"
  65 #include "alias.h"
  66 #include "symtab.h"
  67 #include "inchash.h"
  68 #include "tree.h"
  69 #include "fold-const.h"
  70 #include "stor-layout.h"
  71 #include "tree-pretty-print.h"
  72 #include "predict.h"
  73 #include "hard-reg-set.h"
  74 #include "input.h"
  75 #include "function.h"
  76 #include "dominance.h"
  77 #include "cfg.h"
  78 #include "basic-block.h"
  79 #include "tree-ssa-alias.h"
  80 #include "internal-fn.h"
  81 #include "gimple-expr.h"
  82 #include "is-a.h"
  83 #include "gimple.h"
  84 #include "gimple-iterator.h"
  85 #include "gimple-walk.h"
  86 #include "gimple-ssa.h"
  87 #include "hash-map.h"
  88 #include "plugin-api.h"
  89 #include "ipa-ref.h"
  90 #include "cgraph.h"
  91 #include "tree-phinodes.h"
  92 #include "ssa-iterators.h"
  93 #include "tree-ssa-loop-manip.h"
  94 #include "tree-cfg.h"
  95 #include "cfgloop.h"
  96 #include "tree-vectorizer.h"
  97 #include "tree-pass.h"
  98 #include "tree-ssa-propagate.h"
  99 #include "dbgcnt.h"
 100 #include "gimple-fold.h"
 101 #include "tree-scalar-evolution.h"
 102
 103
 104 /* Loop or bb location.  */
 105 source_location vect_location;
 106
 107 /* Vector mapping GIMPLE stmt to stmt_vec_info. */
 108 vec<vec_void_p> stmt_vec_info_vec;
 109 \f
 110 /* For mapping simduid to vectorization factor.  */
 111
 112 struct simduid_to_vf : typed_free_remove<simduid_to_vf>
 113 {
 114   unsigned int simduid;
 115   int vf;
 116
 117   /* hash_table support.  */
 118   typedef simduid_to_vf *value_type;
 119   typedef simduid_to_vf *compare_type;
 120   static inline hashval_t hash (const simduid_to_vf *);
 121   static inline int equal (const simduid_to_vf *, const simduid_to_vf *);
 122 };
 123
 124 inline hashval_t
 125 simduid_to_vf::hash (const simduid_to_vf *p)
 126 {
 127   return p->simduid;
 128 }
 129
 130 inline int
 131 simduid_to_vf::equal (const simduid_to_vf *p1, const simduid_to_vf *p2)
 132 {
 133   return p1->simduid == p2->simduid;
 134 }
 135
 136 /* This hash maps the OMP simd array to the corresponding simduid used
 137    to index into it.  Like thus,
 138
 139         _7 = GOMP_SIMD_LANE (simduid.0)
 140         ...
 141         ...
 142         D.1737[_7] = stuff;
 143
 144
 145    This hash maps from the OMP simd array (D.1737[]) to DECL_UID of
 146    simduid.0.  */
 147
 148 struct simd_array_to_simduid : typed_free_remove<simd_array_to_simduid>
 149 {
 150   tree decl;
 151   unsigned int simduid;
 152
 153   /* hash_table support.  */
 154   typedef simd_array_to_simduid *value_type;
 155   typedef simd_array_to_simduid *compare_type;
 156   static inline hashval_t hash (const simd_array_to_simduid *);
 157   static inline int equal (const simd_array_to_simduid *,
 158                            const simd_array_to_simduid *);
 159 };
 160
 161 inline hashval_t
 162 simd_array_to_simduid::hash (const simd_array_to_simduid *p)
 163 {
 164   return DECL_UID (p->decl);
 165 }
 166
 167 inline int
 168 simd_array_to_simduid::equal (const simd_array_to_simduid *p1,
 169                               const simd_array_to_simduid *p2)
 170 {
 171   return p1->decl == p2->decl;
 172 }
 173
 174 /* Fold IFN_GOMP_SIMD_LANE, IFN_GOMP_SIMD_VF and IFN_GOMP_SIMD_LAST_LANE
 175    into their corresponding constants.  */
 176
 177 static void
 178 adjust_simduid_builtins (hash_table<simduid_to_vf> **htab)
 179 {
 180   basic_block bb;
 181
 182   FOR_EACH_BB_FN (bb, cfun)
 183     {
 184       gimple_stmt_iterator i;
 185
 186       for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
 187         {
 188           unsigned int vf = 1;
 189           enum internal_fn ifn;
 190           gimple stmt = gsi_stmt (i);
 191           tree t;
 192           if (!is_gimple_call (stmt)
 193               || !gimple_call_internal_p (stmt))
 194             continue;
 195           ifn = gimple_call_internal_fn (stmt);
 196           switch (ifn)
 197             {
 198             case IFN_GOMP_SIMD_LANE:
 199             case IFN_GOMP_SIMD_VF:
 200             case IFN_GOMP_SIMD_LAST_LANE:
 201               break;
 202             default:
 203               continue;
 204             }
 205           tree arg = gimple_call_arg (stmt, 0);
 206           gcc_assert (arg != NULL_TREE);
 207           gcc_assert (TREE_CODE (arg) == SSA_NAME);
 208           simduid_to_vf *p = NULL, data;
 209           data.simduid = DECL_UID (SSA_NAME_VAR (arg));
 210           if (*htab)
 211             p = (*htab)->find (&data);
 212           if (p)
 213             vf = p->vf;
 214           switch (ifn)
 215             {
 216             case IFN_GOMP_SIMD_VF:
 217               t = build_int_cst (unsigned_type_node, vf);
 218               break;
 219             case IFN_GOMP_SIMD_LANE:
 220               t = build_int_cst (unsigned_type_node, 0);
 221               break;
 222             case IFN_GOMP_SIMD_LAST_LANE:
 223               t = gimple_call_arg (stmt, 1);
 224               break;
 225             default:
 226               gcc_unreachable ();
 227             }
 228           update_call_from_tree (&i, t);
 229         }
 230     }
 231 }
 232
 233 /* Helper structure for note_simd_array_uses.  */
 234
 235 struct note_simd_array_uses_struct
 236 {
 237   hash_table<simd_array_to_simduid> **htab;
 238   unsigned int simduid;
 239 };
 240
 241 /* Callback for note_simd_array_uses, called through walk_gimple_op.  */
 242
 243 static tree
 244 note_simd_array_uses_cb (tree *tp, int *walk_subtrees, void *data)
 245 {
 246   struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
 247   struct note_simd_array_uses_struct *ns
 248     = (struct note_simd_array_uses_struct *) wi->info;
 249
 250   if (TYPE_P (*tp))
 251     *walk_subtrees = 0;
 252   else if (VAR_P (*tp)
 253            && lookup_attribute ("omp simd array", DECL_ATTRIBUTES (*tp))
 254            && DECL_CONTEXT (*tp) == current_function_decl)
 255     {
 256       simd_array_to_simduid data;
 257       if (!*ns->htab)
 258         *ns->htab = new hash_table<simd_array_to_simduid> (15);
 259       data.decl = *tp;
 260       data.simduid = ns->simduid;
 261       simd_array_to_simduid **slot = (*ns->htab)->find_slot (&data, INSERT);
 262       if (*slot == NULL)
 263         {
 264           simd_array_to_simduid *p = XNEW (simd_array_to_simduid);
 265           *p = data;
 266           *slot = p;
 267         }
 268       else if ((*slot)->simduid != ns->simduid)
 269         (*slot)->simduid = -1U;
 270       *walk_subtrees = 0;
 271     }
 272   return NULL_TREE;
 273 }
 274
 275 /* Find "omp simd array" temporaries and map them to corresponding
 276    simduid.  */
 277
 278 static void
 279 note_simd_array_uses (hash_table<simd_array_to_simduid> **htab)
 280 {
 281   basic_block bb;
 282   gimple_stmt_iterator gsi;
 283   struct walk_stmt_info wi;
 284   struct note_simd_array_uses_struct ns;
 285
 286   memset (&wi, 0, sizeof (wi));
 287   wi.info = &ns;
 288   ns.htab = htab;
 289
 290   FOR_EACH_BB_FN (bb, cfun)
 291     for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
 292       {
 293         gimple stmt = gsi_stmt (gsi);
 294         if (!is_gimple_call (stmt) || !gimple_call_internal_p (stmt))
 295           continue;
 296         switch (gimple_call_internal_fn (stmt))
 297           {
 298           case IFN_GOMP_SIMD_LANE:
 299           case IFN_GOMP_SIMD_VF:
 300           case IFN_GOMP_SIMD_LAST_LANE:
 301             break;
 302           default:
 303             continue;
 304           }
 305         tree lhs = gimple_call_lhs (stmt);
 306         if (lhs == NULL_TREE)
 307           continue;
 308         imm_use_iterator use_iter;
 309         gimple use_stmt;
 310         ns.simduid = DECL_UID (SSA_NAME_VAR (gimple_call_arg (stmt, 0)));
 311         FOR_EACH_IMM_USE_STMT (use_stmt, use_iter, lhs)
 312           if (!is_gimple_debug (use_stmt))
 313             walk_gimple_op (use_stmt, note_simd_array_uses_cb, &wi);
 314       }
 315 }
 316 \f
 317 /* A helper function to free data refs.  */
 318
 319 void
 320 vect_destroy_datarefs (loop_vec_info loop_vinfo, bb_vec_info bb_vinfo)
 321 {
 322   vec<data_reference_p> datarefs;
 323   struct data_reference *dr;
 324   unsigned int i;
 325
 326  if (loop_vinfo)
 327     datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
 328   else
 329     datarefs = BB_VINFO_DATAREFS (bb_vinfo);
 330
 331   FOR_EACH_VEC_ELT (datarefs, i, dr)
 332     if (dr->aux)
 333       {
 334         free (dr->aux);
 335         dr->aux = NULL;
 336       }
 337
 338   free_data_refs (datarefs);
 339 }
 340
 341
 342 /* If LOOP has been versioned during ifcvt, return the internal call
 343    guarding it.  */
 344
 345 static gimple
 346 vect_loop_vectorized_call (struct loop *loop)
 347 {
 348   basic_block bb = loop_preheader_edge (loop)->src;
 349   gimple g;
 350   do
 351     {
 352       g = last_stmt (bb);
 353       if (g)
 354         break;
 355       if (!single_pred_p (bb))
 356         break;
 357       bb = single_pred (bb);
 358     }
 359   while (1);
 360   if (g && gimple_code (g) == GIMPLE_COND)
 361     {
 362       gimple_stmt_iterator gsi = gsi_for_stmt (g);
 363       gsi_prev (&gsi);
 364       if (!gsi_end_p (gsi))
 365         {
 366           g = gsi_stmt (gsi);
 367           if (is_gimple_call (g)
 368               && gimple_call_internal_p (g)
 369               && gimple_call_internal_fn (g) == IFN_LOOP_VECTORIZED
 370               && (tree_to_shwi (gimple_call_arg (g, 0)) == loop->num
 371                   || tree_to_shwi (gimple_call_arg (g, 1)) == loop->num))
 372             return g;
 373         }
 374     }
 375   return NULL;
 376 }
 377
 378 /* Fold LOOP_VECTORIZED internal call G to VALUE and
 379    update any immediate uses of it's LHS.  */
 380
 381 static void
 382 fold_loop_vectorized_call (gimple g, tree value)
 383 {
 384   tree lhs = gimple_call_lhs (g);
 385   use_operand_p use_p;
 386   imm_use_iterator iter;
 387   gimple use_stmt;
 388   gimple_stmt_iterator gsi = gsi_for_stmt (g);
 389
 390   update_call_from_tree (&gsi, value);
 391   FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs)
 392     {
 393       FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 394         SET_USE (use_p, value);
 395       update_stmt (use_stmt);
 396     }
 397 }
 398 /* Set the uids of all the statements in basic blocks inside loop
 399    represented by LOOP_VINFO. LOOP_VECTORIZED_CALL is the internal
 400    call guarding the loop which has been if converted.  */
 401 static void
 402 set_uid_loop_bbs (loop_vec_info loop_vinfo, gimple loop_vectorized_call)
 403 {
 404   tree arg = gimple_call_arg (loop_vectorized_call, 1);
 405   basic_block *bbs;
 406   unsigned int i;
 407   struct loop *scalar_loop = get_loop (cfun, tree_to_shwi (arg));
 408
 409   LOOP_VINFO_SCALAR_LOOP (loop_vinfo) = scalar_loop;
 410   gcc_checking_assert (vect_loop_vectorized_call
 411                        (LOOP_VINFO_SCALAR_LOOP (loop_vinfo))
 412                        == loop_vectorized_call);
 413   bbs = get_loop_body (scalar_loop);
 414   for (i = 0; i < scalar_loop->num_nodes; i++)
 415     {
 416       basic_block bb = bbs[i];
 417       gimple_stmt_iterator gsi;
 418       for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
 419         {
 420           gimple phi = gsi_stmt (gsi);
 421           gimple_set_uid (phi, 0);
 422         }
 423       for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
 424         {
 425           gimple stmt = gsi_stmt (gsi);
 426           gimple_set_uid (stmt, 0);
 427         }
 428     }
 429   free (bbs);
 430 }
 431
 432 /* Function vectorize_loops.
 433
 434    Entry point to loop vectorization phase.  */
 435
 436 unsigned
 437 vectorize_loops (void)
 438 {
 439   unsigned int i;
 440   unsigned int num_vectorized_loops = 0;
 441   unsigned int vect_loops_num;
 442   struct loop *loop;
 443   hash_table<simduid_to_vf> *simduid_to_vf_htab = NULL;
 444   hash_table<simd_array_to_simduid> *simd_array_to_simduid_htab = NULL;
 445   bool any_ifcvt_loops = false;
 446   unsigned ret = 0;
 447
 448   vect_loops_num = number_of_loops (cfun);
 449
 450   /* Bail out if there are no loops.  */
 451   if (vect_loops_num <= 1)
 452     {
 453       if (cfun->has_simduid_loops)
 454         adjust_simduid_builtins (&simduid_to_vf_htab);
 455       return 0;
 456     }
 457
 458   if (cfun->has_simduid_loops)
 459     note_simd_array_uses (&simd_array_to_simduid_htab);
 460
 461   init_stmt_vec_info_vec ();
 462
 463   /*  ----------- Analyze loops. -----------  */
 464
 465   /* If some loop was duplicated, it gets bigger number
 466      than all previously defined loops.  This fact allows us to run
 467      only over initial loops skipping newly generated ones.  */
 468   FOR_EACH_LOOP (loop, 0)
 469     if (loop->dont_vectorize)
 470       any_ifcvt_loops = true;
 471     else if ((flag_tree_loop_vectorize
 472               && optimize_loop_nest_for_speed_p (loop))
 473              || loop->force_vectorize)
 474       {
 475         loop_vec_info loop_vinfo;
 476         vect_location = find_loop_location (loop);
 477         if (LOCATION_LOCUS (vect_location) != UNKNOWN_LOCATION
 478             && dump_enabled_p ())
 479           dump_printf (MSG_NOTE, "\nAnalyzing loop at %s:%d\n",
 480                        LOCATION_FILE (vect_location),
 481                        LOCATION_LINE (vect_location));
 482
 483         loop_vinfo = vect_analyze_loop (loop);
 484         loop->aux = loop_vinfo;
 485
 486         if (!loop_vinfo || !LOOP_VINFO_VECTORIZABLE_P (loop_vinfo))
 487           continue;
 488
 489         if (!dbg_cnt (vect_loop))
 490           break;
 491
 492         gimple loop_vectorized_call = vect_loop_vectorized_call (loop);
 493         if (loop_vectorized_call)
 494           set_uid_loop_bbs (loop_vinfo, loop_vectorized_call);
 495         if (LOCATION_LOCUS (vect_location) != UNKNOWN_LOCATION
 496             && dump_enabled_p ())
 497           dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, vect_location,
 498                            "loop vectorized\n");
 499         vect_transform_loop (loop_vinfo);
 500         num_vectorized_loops++;
 501         /* Now that the loop has been vectorized, allow it to be unrolled
 502            etc.  */
 503         loop->force_vectorize = false;
 504
 505         if (loop->simduid)
 506           {
 507             simduid_to_vf *simduid_to_vf_data = XNEW (simduid_to_vf);
 508             if (!simduid_to_vf_htab)
 509               simduid_to_vf_htab = new hash_table<simduid_to_vf> (15);
 510             simduid_to_vf_data->simduid = DECL_UID (loop->simduid);
 511             simduid_to_vf_data->vf = loop_vinfo->vectorization_factor;
 512             *simduid_to_vf_htab->find_slot (simduid_to_vf_data, INSERT)
 513               = simduid_to_vf_data;
 514           }
 515
 516         if (loop_vectorized_call)
 517           {
 518             fold_loop_vectorized_call (loop_vectorized_call, boolean_true_node);
 519             ret |= TODO_cleanup_cfg;
 520           }
 521       }
 522
 523   vect_location = UNKNOWN_LOCATION;
 524
 525   statistics_counter_event (cfun, "Vectorized loops", num_vectorized_loops);
 526   if (dump_enabled_p ()
 527       || (num_vectorized_loops > 0 && dump_enabled_p ()))
 528     dump_printf_loc (MSG_NOTE, vect_location,
 529                      "vectorized %u loops in function.\n",
 530                      num_vectorized_loops);
 531
 532   /*  ----------- Finalize. -----------  */
 533
 534   if (any_ifcvt_loops)
 535     for (i = 1; i < vect_loops_num; i++)
 536       {
 537         loop = get_loop (cfun, i);
 538         if (loop && loop->dont_vectorize)
 539           {
 540             gimple g = vect_loop_vectorized_call (loop);
 541             if (g)
 542               {
 543                 fold_loop_vectorized_call (g, boolean_false_node);
 544                 ret |= TODO_cleanup_cfg;
 545               }
 546           }
 547       }
 548
 549   for (i = 1; i < vect_loops_num; i++)
 550     {
 551       loop_vec_info loop_vinfo;
 552
 553       loop = get_loop (cfun, i);
 554       if (!loop)
 555         continue;
 556       loop_vinfo = (loop_vec_info) loop->aux;
 557       destroy_loop_vec_info (loop_vinfo, true);
 558       loop->aux = NULL;
 559     }
 560
 561   free_stmt_vec_info_vec ();
 562
 563   /* Fold IFN_GOMP_SIMD_{VF,LANE,LAST_LANE} builtins.  */
 564   if (cfun->has_simduid_loops)
 565     adjust_simduid_builtins (&simduid_to_vf_htab);
 566
 567   /* Shrink any "omp array simd" temporary arrays to the
 568      actual vectorization factors.  */
 569   if (simd_array_to_simduid_htab)
 570     {
 571       for (hash_table<simd_array_to_simduid>::iterator iter
 572            = simd_array_to_simduid_htab->begin ();
 573            iter != simd_array_to_simduid_htab->end (); ++iter)
 574         if ((*iter)->simduid != -1U)
 575           {
 576             tree decl = (*iter)->decl;
 577             int vf = 1;
 578             if (simduid_to_vf_htab)
 579               {
 580                 simduid_to_vf *p = NULL, data;
 581                 data.simduid = (*iter)->simduid;
 582                 p = simduid_to_vf_htab->find (&data);
 583                 if (p)
 584                   vf = p->vf;
 585               }
 586             tree atype
 587               = build_array_type_nelts (TREE_TYPE (TREE_TYPE (decl)), vf);
 588             TREE_TYPE (decl) = atype;
 589             relayout_decl (decl);
 590           }
 591
 592       delete simd_array_to_simduid_htab;
 593     }
 594     delete simduid_to_vf_htab;
 595     simduid_to_vf_htab = NULL;
 596
 597   if (num_vectorized_loops > 0)
 598     {
 599       /* If we vectorized any loop only virtual SSA form needs to be updated.
 600          ???  Also while we try hard to update loop-closed SSA form we fail
 601          to properly do this in some corner-cases (see PR56286).  */
 602       rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa_only_virtuals);
 603       return TODO_cleanup_cfg;
 604     }
 605
 606   return ret;
 607 }
 608
 609
 610 /*  Entry point to basic block SLP phase.  */
 611
 612 namespace {
 613
 614 const pass_data pass_data_slp_vectorize =
 615 {
 616   GIMPLE_PASS, /* type */
 617   "slp", /* name */
 618   OPTGROUP_LOOP | OPTGROUP_VEC, /* optinfo_flags */
 619   TV_TREE_SLP_VECTORIZATION, /* tv_id */
 620   ( PROP_ssa | PROP_cfg ), /* properties_required */
 621   0, /* properties_provided */
 622   0, /* properties_destroyed */
 623   0, /* todo_flags_start */
 624   TODO_update_ssa, /* todo_flags_finish */
 625 };
 626
 627 class pass_slp_vectorize : public gimple_opt_pass
 628 {
 629 public:
 630   pass_slp_vectorize (gcc::context *ctxt)
 631     : gimple_opt_pass (pass_data_slp_vectorize, ctxt)
 632   {}
 633
 634   /* opt_pass methods: */
 635   opt_pass * clone () { return new pass_slp_vectorize (m_ctxt); }
 636   virtual bool gate (function *) { return flag_tree_slp_vectorize != 0; }
 637   virtual unsigned int execute (function *);
 638
 639 }; // class pass_slp_vectorize
 640
 641 unsigned int
 642 pass_slp_vectorize::execute (function *fun)
 643 {
 644   basic_block bb;
 645
 646   bool in_loop_pipeline = scev_initialized_p ();
 647   if (!in_loop_pipeline)
 648     {
 649       loop_optimizer_init (LOOPS_NORMAL);
 650       scev_initialize ();
 651     }
 652
 653   init_stmt_vec_info_vec ();
 654
 655   FOR_EACH_BB_FN (bb, fun)
 656     {
 657       vect_location = find_bb_location (bb);
 658
 659       if (vect_slp_analyze_bb (bb))
 660         {
 661           if (!dbg_cnt (vect_slp))
 662             break;
 663
 664           vect_slp_transform_bb (bb);
 665           if (dump_enabled_p ())
 666             dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, vect_location,
 667                              "basic block vectorized\n");
 668         }
 669     }
 670
 671   free_stmt_vec_info_vec ();
 672
 673   if (!in_loop_pipeline)
 674     {
 675       scev_finalize ();
 676       loop_optimizer_finalize ();
 677     }
 678
 679   return 0;
 680 }
 681
 682 } // anon namespace
 683
 684 gimple_opt_pass *
 685 make_pass_slp_vectorize (gcc::context *ctxt)
 686 {
 687   return new pass_slp_vectorize (ctxt);
 688 }
 689
 690
 691 /* Increase alignment of global arrays to improve vectorization potential.
 692    TODO:
 693    - Consider also structs that have an array field.
 694    - Use ipa analysis to prune arrays that can't be vectorized?
 695      This should involve global alignment analysis and in the future also
 696      array padding.  */
 697
 698 static unsigned int
 699 increase_alignment (void)
 700 {
 701   varpool_node *vnode;
 702
 703   vect_location = UNKNOWN_LOCATION;
 704
 705   /* Increase the alignment of all global arrays for vectorization.  */
 706   FOR_EACH_DEFINED_VARIABLE (vnode)
 707     {
 708       tree vectype, decl = vnode->decl;
 709       tree t;
 710       unsigned int alignment;
 711
 712       t = TREE_TYPE (decl);
 713       if (TREE_CODE (t) != ARRAY_TYPE)
 714         continue;
 715       vectype = get_vectype_for_scalar_type (strip_array_types (t));
 716       if (!vectype)
 717         continue;
 718       alignment = TYPE_ALIGN (vectype);
 719       if (DECL_ALIGN (decl) >= alignment)
 720         continue;
 721
 722       if (vect_can_force_dr_alignment_p (decl, alignment))
 723         {
 724           vnode->increase_alignment (TYPE_ALIGN (vectype));
 725           dump_printf (MSG_NOTE, "Increasing alignment of decl: ");
 726           dump_generic_expr (MSG_NOTE, TDF_SLIM, decl);
 727           dump_printf (MSG_NOTE, "\n");
 728         }
 729     }
 730   return 0;
 731 }
 732
 733
 734 namespace {
 735
 736 const pass_data pass_data_ipa_increase_alignment =
 737 {
 738   SIMPLE_IPA_PASS, /* type */
 739   "increase_alignment", /* name */
 740   OPTGROUP_LOOP | OPTGROUP_VEC, /* optinfo_flags */
 741   TV_IPA_OPT, /* tv_id */
 742   0, /* properties_required */
 743   0, /* properties_provided */
 744   0, /* properties_destroyed */
 745   0, /* todo_flags_start */
 746   0, /* todo_flags_finish */
 747 };
 748
 749 class pass_ipa_increase_alignment : public simple_ipa_opt_pass
 750 {
 751 public:
 752   pass_ipa_increase_alignment (gcc::context *ctxt)
 753     : simple_ipa_opt_pass (pass_data_ipa_increase_alignment, ctxt)
 754   {}
 755
 756   /* opt_pass methods: */
 757   virtual bool gate (function *)
 758     {
 759       return flag_section_anchors && flag_tree_loop_vectorize;
 760     }
 761
 762   virtual unsigned int execute (function *) { return increase_alignment (); }
 763
 764 }; // class pass_ipa_increase_alignment
 765
 766 } // anon namespace
 767
 768 simple_ipa_opt_pass *
 769 make_pass_ipa_increase_alignment (gcc::context *ctxt)
 770 {
 771   return new pass_ipa_increase_alignment (ctxt);
 772 }