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 "machmode.h"
  64 #include "vec.h"
  65 #include "double-int.h"
  66 #include "input.h"
  67 #include "alias.h"
  68 #include "symtab.h"
  69 #include "wide-int.h"
  70 #include "inchash.h"
  71 #include "tree.h"
  72 #include "fold-const.h"
  73 #include "stor-layout.h"
  74 #include "tree-pretty-print.h"
  75 #include "predict.h"
  76 #include "hard-reg-set.h"
  77 #include "input.h"
  78 #include "function.h"
  79 #include "dominance.h"
  80 #include "cfg.h"
  81 #include "basic-block.h"
  82 #include "tree-ssa-alias.h"
  83 #include "internal-fn.h"
  84 #include "gimple-expr.h"
  85 #include "is-a.h"
  86 #include "gimple.h"
  87 #include "gimple-iterator.h"
  88 #include "gimple-walk.h"
  89 #include "gimple-ssa.h"
  90 #include "hash-map.h"
  91 #include "plugin-api.h"
  92 #include "ipa-ref.h"
  93 #include "cgraph.h"
  94 #include "tree-phinodes.h"
  95 #include "ssa-iterators.h"
  96 #include "tree-ssa-loop-manip.h"
  97 #include "tree-cfg.h"
  98 #include "cfgloop.h"
  99 #include "tree-vectorizer.h"
 100 #include "tree-pass.h"
 101 #include "tree-ssa-propagate.h"
 102 #include "dbgcnt.h"
 103 #include "gimple-fold.h"
 104 #include "tree-scalar-evolution.h"
 105
 106
 107 /* Loop or bb location.  */
 108 source_location vect_location;
 109
 110 /* Vector mapping GIMPLE stmt to stmt_vec_info. */
 111 vec<vec_void_p> stmt_vec_info_vec;
 112 \f
 113 /* For mapping simduid to vectorization factor.  */
 114
 115 struct simduid_to_vf : typed_free_remove<simduid_to_vf>
 116 {
 117   unsigned int simduid;
 118   int vf;
 119
 120   /* hash_table support.  */
 121   typedef simduid_to_vf value_type;
 122   typedef simduid_to_vf compare_type;
 123   static inline hashval_t hash (const value_type *);
 124   static inline int equal (const value_type *, const compare_type *);
 125 };
 126
 127 inline hashval_t
 128 simduid_to_vf::hash (const value_type *p)
 129 {
 130   return p->simduid;
 131 }
 132
 133 inline int
 134 simduid_to_vf::equal (const value_type *p1, const value_type *p2)
 135 {
 136   return p1->simduid == p2->simduid;
 137 }
 138
 139 /* This hash maps the OMP simd array to the corresponding simduid used
 140    to index into it.  Like thus,
 141
 142         _7 = GOMP_SIMD_LANE (simduid.0)
 143         ...
 144         ...
 145         D.1737[_7] = stuff;
 146
 147
 148    This hash maps from the OMP simd array (D.1737[]) to DECL_UID of
 149    simduid.0.  */
 150
 151 struct simd_array_to_simduid : typed_free_remove<simd_array_to_simduid>
 152 {
 153   tree decl;
 154   unsigned int simduid;
 155
 156   /* hash_table support.  */
 157   typedef simd_array_to_simduid value_type;
 158   typedef simd_array_to_simduid compare_type;
 159   static inline hashval_t hash (const value_type *);
 160   static inline int equal (const value_type *, const compare_type *);
 161 };
 162
 163 inline hashval_t
 164 simd_array_to_simduid::hash (const value_type *p)
 165 {
 166   return DECL_UID (p->decl);
 167 }
 168
 169 inline int
 170 simd_array_to_simduid::equal (const value_type *p1, const value_type *p2)
 171 {
 172   return p1->decl == p2->decl;
 173 }
 174
 175 /* Fold IFN_GOMP_SIMD_LANE, IFN_GOMP_SIMD_VF and IFN_GOMP_SIMD_LAST_LANE
 176    into their corresponding constants.  */
 177
 178 static void
 179 adjust_simduid_builtins (hash_table<simduid_to_vf> **htab)
 180 {
 181   basic_block bb;
 182
 183   FOR_EACH_BB_FN (bb, cfun)
 184     {
 185       gimple_stmt_iterator i;
 186
 187       for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
 188         {
 189           unsigned int vf = 1;
 190           enum internal_fn ifn;
 191           gimple stmt = gsi_stmt (i);
 192           tree t;
 193           if (!is_gimple_call (stmt)
 194               || !gimple_call_internal_p (stmt))
 195             continue;
 196           ifn = gimple_call_internal_fn (stmt);
 197           switch (ifn)
 198             {
 199             case IFN_GOMP_SIMD_LANE:
 200             case IFN_GOMP_SIMD_VF:
 201             case IFN_GOMP_SIMD_LAST_LANE:
 202               break;
 203             default:
 204               continue;
 205             }
 206           tree arg = gimple_call_arg (stmt, 0);
 207           gcc_assert (arg != NULL_TREE);
 208           gcc_assert (TREE_CODE (arg) == SSA_NAME);
 209           simduid_to_vf *p = NULL, data;
 210           data.simduid = DECL_UID (SSA_NAME_VAR (arg));
 211           if (*htab)
 212             p = (*htab)->find (&data);
 213           if (p)
 214             vf = p->vf;
 215           switch (ifn)
 216             {
 217             case IFN_GOMP_SIMD_VF:
 218               t = build_int_cst (unsigned_type_node, vf);
 219               break;
 220             case IFN_GOMP_SIMD_LANE:
 221               t = build_int_cst (unsigned_type_node, 0);
 222               break;
 223             case IFN_GOMP_SIMD_LAST_LANE:
 224               t = gimple_call_arg (stmt, 1);
 225               break;
 226             default:
 227               gcc_unreachable ();
 228             }
 229           update_call_from_tree (&i, t);
 230         }
 231     }
 232 }
 233
 234 /* Helper structure for note_simd_array_uses.  */
 235
 236 struct note_simd_array_uses_struct
 237 {
 238   hash_table<simd_array_to_simduid> **htab;
 239   unsigned int simduid;
 240 };
 241
 242 /* Callback for note_simd_array_uses, called through walk_gimple_op.  */
 243
 244 static tree
 245 note_simd_array_uses_cb (tree *tp, int *walk_subtrees, void *data)
 246 {
 247   struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
 248   struct note_simd_array_uses_struct *ns
 249     = (struct note_simd_array_uses_struct *) wi->info;
 250
 251   if (TYPE_P (*tp))
 252     *walk_subtrees = 0;
 253   else if (VAR_P (*tp)
 254            && lookup_attribute ("omp simd array", DECL_ATTRIBUTES (*tp))
 255            && DECL_CONTEXT (*tp) == current_function_decl)
 256     {
 257       simd_array_to_simduid data;
 258       if (!*ns->htab)
 259         *ns->htab = new hash_table<simd_array_to_simduid> (15);
 260       data.decl = *tp;
 261       data.simduid = ns->simduid;
 262       simd_array_to_simduid **slot = (*ns->htab)->find_slot (&data, INSERT);
 263       if (*slot == NULL)
 264         {
 265           simd_array_to_simduid *p = XNEW (simd_array_to_simduid);
 266           *p = data;
 267           *slot = p;
 268         }
 269       else if ((*slot)->simduid != ns->simduid)
 270         (*slot)->simduid = -1U;
 271       *walk_subtrees = 0;
 272     }
 273   return NULL_TREE;
 274 }
 275
 276 /* Find "omp simd array" temporaries and map them to corresponding
 277    simduid.  */
 278
 279 static void
 280 note_simd_array_uses (hash_table<simd_array_to_simduid> **htab)
 281 {
 282   basic_block bb;
 283   gimple_stmt_iterator gsi;
 284   struct walk_stmt_info wi;
 285   struct note_simd_array_uses_struct ns;
 286
 287   memset (&wi, 0, sizeof (wi));
 288   wi.info = &ns;
 289   ns.htab = htab;
 290
 291   FOR_EACH_BB_FN (bb, cfun)
 292     for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
 293       {
 294         gimple stmt = gsi_stmt (gsi);
 295         if (!is_gimple_call (stmt) || !gimple_call_internal_p (stmt))
 296           continue;
 297         switch (gimple_call_internal_fn (stmt))
 298           {
 299           case IFN_GOMP_SIMD_LANE:
 300           case IFN_GOMP_SIMD_VF:
 301           case IFN_GOMP_SIMD_LAST_LANE:
 302             break;
 303           default:
 304             continue;
 305           }
 306         tree lhs = gimple_call_lhs (stmt);
 307         if (lhs == NULL_TREE)
 308           continue;
 309         imm_use_iterator use_iter;
 310         gimple use_stmt;
 311         ns.simduid = DECL_UID (SSA_NAME_VAR (gimple_call_arg (stmt, 0)));
 312         FOR_EACH_IMM_USE_STMT (use_stmt, use_iter, lhs)
 313           if (!is_gimple_debug (use_stmt))
 314             walk_gimple_op (use_stmt, note_simd_array_uses_cb, &wi);
 315       }
 316 }
 317 \f
 318 /* A helper function to free data refs.  */
 319
 320 void
 321 vect_destroy_datarefs (loop_vec_info loop_vinfo, bb_vec_info bb_vinfo)
 322 {
 323   vec<data_reference_p> datarefs;
 324   struct data_reference *dr;
 325   unsigned int i;
 326
 327  if (loop_vinfo)
 328     datarefs = LOOP_VINFO_DATAREFS (loop_vinfo);
 329   else
 330     datarefs = BB_VINFO_DATAREFS (bb_vinfo);
 331
 332   FOR_EACH_VEC_ELT (datarefs, i, dr)
 333     if (dr->aux)
 334       {
 335         free (dr->aux);
 336         dr->aux = NULL;
 337       }
 338
 339   free_data_refs (datarefs);
 340 }
 341
 342
 343 /* If LOOP has been versioned during ifcvt, return the internal call
 344    guarding it.  */
 345
 346 static gimple
 347 vect_loop_vectorized_call (struct loop *loop)
 348 {
 349   basic_block bb = loop_preheader_edge (loop)->src;
 350   gimple g;
 351   do
 352     {
 353       g = last_stmt (bb);
 354       if (g)
 355         break;
 356       if (!single_pred_p (bb))
 357         break;
 358       bb = single_pred (bb);
 359     }
 360   while (1);
 361   if (g && gimple_code (g) == GIMPLE_COND)
 362     {
 363       gimple_stmt_iterator gsi = gsi_for_stmt (g);
 364       gsi_prev (&gsi);
 365       if (!gsi_end_p (gsi))
 366         {
 367           g = gsi_stmt (gsi);
 368           if (is_gimple_call (g)
 369               && gimple_call_internal_p (g)
 370               && gimple_call_internal_fn (g) == IFN_LOOP_VECTORIZED
 371               && (tree_to_shwi (gimple_call_arg (g, 0)) == loop->num
 372                   || tree_to_shwi (gimple_call_arg (g, 1)) == loop->num))
 373             return g;
 374         }
 375     }
 376   return NULL;
 377 }
 378
 379 /* Fold LOOP_VECTORIZED internal call G to VALUE and
 380    update any immediate uses of it's LHS.  */
 381
 382 static void
 383 fold_loop_vectorized_call (gimple g, tree value)
 384 {
 385   tree lhs = gimple_call_lhs (g);
 386   use_operand_p use_p;
 387   imm_use_iterator iter;
 388   gimple use_stmt;
 389   gimple_stmt_iterator gsi = gsi_for_stmt (g);
 390
 391   update_call_from_tree (&gsi, value);
 392   FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs)
 393     {
 394       FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
 395         SET_USE (use_p, value);
 396       update_stmt (use_stmt);
 397     }
 398 }
 399
 400 /* Function vectorize_loops.
 401
 402    Entry point to loop vectorization phase.  */
 403
 404 unsigned
 405 vectorize_loops (void)
 406 {
 407   unsigned int i;
 408   unsigned int num_vectorized_loops = 0;
 409   unsigned int vect_loops_num;
 410   struct loop *loop;
 411   hash_table<simduid_to_vf> *simduid_to_vf_htab = NULL;
 412   hash_table<simd_array_to_simduid> *simd_array_to_simduid_htab = NULL;
 413   bool any_ifcvt_loops = false;
 414   unsigned ret = 0;
 415
 416   vect_loops_num = number_of_loops (cfun);
 417
 418   /* Bail out if there are no loops.  */
 419   if (vect_loops_num <= 1)
 420     {
 421       if (cfun->has_simduid_loops)
 422         adjust_simduid_builtins (&simduid_to_vf_htab);
 423       return 0;
 424     }
 425
 426   if (cfun->has_simduid_loops)
 427     note_simd_array_uses (&simd_array_to_simduid_htab);
 428
 429   init_stmt_vec_info_vec ();
 430
 431   /*  ----------- Analyze loops. -----------  */
 432
 433   /* If some loop was duplicated, it gets bigger number
 434      than all previously defined loops.  This fact allows us to run
 435      only over initial loops skipping newly generated ones.  */
 436   FOR_EACH_LOOP (loop, 0)
 437     if (loop->dont_vectorize)
 438       any_ifcvt_loops = true;
 439     else if ((flag_tree_loop_vectorize
 440               && optimize_loop_nest_for_speed_p (loop))
 441              || loop->force_vectorize)
 442       {
 443         loop_vec_info loop_vinfo;
 444         vect_location = find_loop_location (loop);
 445         if (LOCATION_LOCUS (vect_location) != UNKNOWN_LOCATION
 446             && dump_enabled_p ())
 447           dump_printf (MSG_NOTE, "\nAnalyzing loop at %s:%d\n",
 448                        LOCATION_FILE (vect_location),
 449                        LOCATION_LINE (vect_location));
 450
 451         loop_vinfo = vect_analyze_loop (loop);
 452         loop->aux = loop_vinfo;
 453
 454         if (!loop_vinfo || !LOOP_VINFO_VECTORIZABLE_P (loop_vinfo))
 455           continue;
 456
 457         if (!dbg_cnt (vect_loop))
 458           break;
 459
 460         gimple loop_vectorized_call = vect_loop_vectorized_call (loop);
 461         if (loop_vectorized_call)
 462           {
 463             tree arg = gimple_call_arg (loop_vectorized_call, 1);
 464             basic_block *bbs;
 465             unsigned int i;
 466             struct loop *scalar_loop = get_loop (cfun, tree_to_shwi (arg));
 467
 468             LOOP_VINFO_SCALAR_LOOP (loop_vinfo) = scalar_loop;
 469             gcc_checking_assert (vect_loop_vectorized_call
 470                                         (LOOP_VINFO_SCALAR_LOOP (loop_vinfo))
 471                                  == loop_vectorized_call);
 472             bbs = get_loop_body (scalar_loop);
 473             for (i = 0; i < scalar_loop->num_nodes; i++)
 474               {
 475                 basic_block bb = bbs[i];
 476                 gimple_stmt_iterator gsi;
 477                 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi);
 478                      gsi_next (&gsi))
 479                   {
 480                     gimple phi = gsi_stmt (gsi);
 481                     gimple_set_uid (phi, 0);
 482                   }
 483                 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi);
 484                      gsi_next (&gsi))
 485                   {
 486                     gimple stmt = gsi_stmt (gsi);
 487                     gimple_set_uid (stmt, 0);
 488                   }
 489               }
 490             free (bbs);
 491           }
 492
 493         if (LOCATION_LOCUS (vect_location) != UNKNOWN_LOCATION
 494             && dump_enabled_p ())
 495           dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, vect_location,
 496                            "loop vectorized\n");
 497         vect_transform_loop (loop_vinfo);
 498         num_vectorized_loops++;
 499         /* Now that the loop has been vectorized, allow it to be unrolled
 500            etc.  */
 501         loop->force_vectorize = false;
 502
 503         if (loop->simduid)
 504           {
 505             simduid_to_vf *simduid_to_vf_data = XNEW (simduid_to_vf);
 506             if (!simduid_to_vf_htab)
 507               simduid_to_vf_htab = new hash_table<simduid_to_vf> (15);
 508             simduid_to_vf_data->simduid = DECL_UID (loop->simduid);
 509             simduid_to_vf_data->vf = loop_vinfo->vectorization_factor;
 510             *simduid_to_vf_htab->find_slot (simduid_to_vf_data, INSERT)
 511               = simduid_to_vf_data;
 512           }
 513
 514         if (loop_vectorized_call)
 515           {
 516             fold_loop_vectorized_call (loop_vectorized_call, boolean_true_node);
 517             ret |= TODO_cleanup_cfg;
 518           }
 519       }
 520
 521   vect_location = UNKNOWN_LOCATION;
 522
 523   statistics_counter_event (cfun, "Vectorized loops", num_vectorized_loops);
 524   if (dump_enabled_p ()
 525       || (num_vectorized_loops > 0 && dump_enabled_p ()))
 526     dump_printf_loc (MSG_NOTE, vect_location,
 527                      "vectorized %u loops in function.\n",
 528                      num_vectorized_loops);
 529
 530   /*  ----------- Finalize. -----------  */
 531
 532   if (any_ifcvt_loops)
 533     for (i = 1; i < vect_loops_num; i++)
 534       {
 535         loop = get_loop (cfun, i);
 536         if (loop && loop->dont_vectorize)
 537           {
 538             gimple g = vect_loop_vectorized_call (loop);
 539             if (g)
 540               {
 541                 fold_loop_vectorized_call (g, boolean_false_node);
 542                 ret |= TODO_cleanup_cfg;
 543               }
 544           }
 545       }
 546
 547   for (i = 1; i < vect_loops_num; i++)
 548     {
 549       loop_vec_info loop_vinfo;
 550
 551       loop = get_loop (cfun, i);
 552       if (!loop)
 553         continue;
 554       loop_vinfo = (loop_vec_info) loop->aux;
 555       destroy_loop_vec_info (loop_vinfo, true);
 556       loop->aux = NULL;
 557     }
 558
 559   free_stmt_vec_info_vec ();
 560
 561   /* Fold IFN_GOMP_SIMD_{VF,LANE,LAST_LANE} builtins.  */
 562   if (cfun->has_simduid_loops)
 563     adjust_simduid_builtins (&simduid_to_vf_htab);
 564
 565   /* Shrink any "omp array simd" temporary arrays to the
 566      actual vectorization factors.  */
 567   if (simd_array_to_simduid_htab)
 568     {
 569       for (hash_table<simd_array_to_simduid>::iterator iter
 570            = simd_array_to_simduid_htab->begin ();
 571            iter != simd_array_to_simduid_htab->end (); ++iter)
 572         if ((*iter)->simduid != -1U)
 573           {
 574             tree decl = (*iter)->decl;
 575             int vf = 1;
 576             if (simduid_to_vf_htab)
 577               {
 578                 simduid_to_vf *p = NULL, data;
 579                 data.simduid = (*iter)->simduid;
 580                 p = simduid_to_vf_htab->find (&data);
 581                 if (p)
 582                   vf = p->vf;
 583               }
 584             tree atype
 585               = build_array_type_nelts (TREE_TYPE (TREE_TYPE (decl)), vf);
 586             TREE_TYPE (decl) = atype;
 587             relayout_decl (decl);
 588           }
 589
 590       delete simd_array_to_simduid_htab;
 591     }
 592     delete simduid_to_vf_htab;
 593     simduid_to_vf_htab = NULL;
 594
 595   if (num_vectorized_loops > 0)
 596     {
 597       /* If we vectorized any loop only virtual SSA form needs to be updated.
 598          ???  Also while we try hard to update loop-closed SSA form we fail
 599          to properly do this in some corner-cases (see PR56286).  */
 600       rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa_only_virtuals);
 601       return TODO_cleanup_cfg;
 602     }
 603
 604   return ret;
 605 }
 606
 607
 608 /*  Entry point to basic block SLP phase.  */
 609
 610 namespace {
 611
 612 const pass_data pass_data_slp_vectorize =
 613 {
 614   GIMPLE_PASS, /* type */
 615   "slp", /* name */
 616   OPTGROUP_LOOP | OPTGROUP_VEC, /* optinfo_flags */
 617   TV_TREE_SLP_VECTORIZATION, /* tv_id */
 618   ( PROP_ssa | PROP_cfg ), /* properties_required */
 619   0, /* properties_provided */
 620   0, /* properties_destroyed */
 621   0, /* todo_flags_start */
 622   TODO_update_ssa, /* todo_flags_finish */
 623 };
 624
 625 class pass_slp_vectorize : public gimple_opt_pass
 626 {
 627 public:
 628   pass_slp_vectorize (gcc::context *ctxt)
 629     : gimple_opt_pass (pass_data_slp_vectorize, ctxt)
 630   {}
 631
 632   /* opt_pass methods: */
 633   opt_pass * clone () { return new pass_slp_vectorize (m_ctxt); }
 634   virtual bool gate (function *) { return flag_tree_slp_vectorize != 0; }
 635   virtual unsigned int execute (function *);
 636
 637 }; // class pass_slp_vectorize
 638
 639 unsigned int
 640 pass_slp_vectorize::execute (function *fun)
 641 {
 642   basic_block bb;
 643
 644   bool in_loop_pipeline = scev_initialized_p ();
 645   if (!in_loop_pipeline)
 646     {
 647       loop_optimizer_init (LOOPS_NORMAL);
 648       scev_initialize ();
 649     }
 650
 651   init_stmt_vec_info_vec ();
 652
 653   FOR_EACH_BB_FN (bb, fun)
 654     {
 655       vect_location = find_bb_location (bb);
 656
 657       if (vect_slp_analyze_bb (bb))
 658         {
 659           if (!dbg_cnt (vect_slp))
 660             break;
 661
 662           vect_slp_transform_bb (bb);
 663           if (dump_enabled_p ())
 664             dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, vect_location,
 665                              "basic block vectorized\n");
 666         }
 667     }
 668
 669   free_stmt_vec_info_vec ();
 670
 671   if (!in_loop_pipeline)
 672     {
 673       scev_finalize ();
 674       loop_optimizer_finalize ();
 675     }
 676
 677   return 0;
 678 }
 679
 680 } // anon namespace
 681
 682 gimple_opt_pass *
 683 make_pass_slp_vectorize (gcc::context *ctxt)
 684 {
 685   return new pass_slp_vectorize (ctxt);
 686 }
 687
 688
 689 /* Increase alignment of global arrays to improve vectorization potential.
 690    TODO:
 691    - Consider also structs that have an array field.
 692    - Use ipa analysis to prune arrays that can't be vectorized?
 693      This should involve global alignment analysis and in the future also
 694      array padding.  */
 695
 696 static unsigned int
 697 increase_alignment (void)
 698 {
 699   varpool_node *vnode;
 700
 701   vect_location = UNKNOWN_LOCATION;
 702
 703   /* Increase the alignment of all global arrays for vectorization.  */
 704   FOR_EACH_DEFINED_VARIABLE (vnode)
 705     {
 706       tree vectype, decl = vnode->decl;
 707       tree t;
 708       unsigned int alignment;
 709
 710       t = TREE_TYPE (decl);
 711       if (TREE_CODE (t) != ARRAY_TYPE)
 712         continue;
 713       vectype = get_vectype_for_scalar_type (strip_array_types (t));
 714       if (!vectype)
 715         continue;
 716       alignment = TYPE_ALIGN (vectype);
 717       if (DECL_ALIGN (decl) >= alignment)
 718         continue;
 719
 720       if (vect_can_force_dr_alignment_p (decl, alignment))
 721         {
 722           DECL_ALIGN (decl) = TYPE_ALIGN (vectype);
 723           DECL_USER_ALIGN (decl) = 1;
 724           if (TREE_STATIC (decl))
 725             {
 726               tree target = symtab_node::get (decl)->ultimate_alias_target ()->decl;
 727               DECL_ALIGN (target) = TYPE_ALIGN (vectype);
 728               DECL_USER_ALIGN (target) = 1;
 729             }
 730           dump_printf (MSG_NOTE, "Increasing alignment of decl: ");
 731           dump_generic_expr (MSG_NOTE, TDF_SLIM, decl);
 732           dump_printf (MSG_NOTE, "\n");
 733         }
 734     }
 735   return 0;
 736 }
 737
 738
 739 namespace {
 740
 741 const pass_data pass_data_ipa_increase_alignment =
 742 {
 743   SIMPLE_IPA_PASS, /* type */
 744   "increase_alignment", /* name */
 745   OPTGROUP_LOOP | OPTGROUP_VEC, /* optinfo_flags */
 746   TV_IPA_OPT, /* tv_id */
 747   0, /* properties_required */
 748   0, /* properties_provided */
 749   0, /* properties_destroyed */
 750   0, /* todo_flags_start */
 751   0, /* todo_flags_finish */
 752 };
 753
 754 class pass_ipa_increase_alignment : public simple_ipa_opt_pass
 755 {
 756 public:
 757   pass_ipa_increase_alignment (gcc::context *ctxt)
 758     : simple_ipa_opt_pass (pass_data_ipa_increase_alignment, ctxt)
 759   {}
 760
 761   /* opt_pass methods: */
 762   virtual bool gate (function *)
 763     {
 764       return flag_section_anchors && flag_tree_loop_vectorize;
 765     }
 766
 767   virtual unsigned int execute (function *) { return increase_alignment (); }
 768
 769 }; // class pass_ipa_increase_alignment
 770
 771 } // anon namespace
 772
 773 simple_ipa_opt_pass *
 774 make_pass_ipa_increase_alignment (gcc::context *ctxt)
 775 {
 776   return new pass_ipa_increase_alignment (ctxt);
 777 }