1 /* Vectorizer
2 Copyright (C) 2003-2022 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.cc - loop specific parts such as reductions, etc. These are
31 used by drivers (1) and (2).
32 - tree-vect-loop-manip.cc - vectorizer's loop control-flow utilities, used by
33 drivers (1) and (2).
34 - tree-vect-slp.cc - BB vectorization specific analysis and transformation,
35 used by drivers (2) and (3).
36 - tree-vect-stmts.cc - statements analysis and transformation (used by all).
37 - tree-vect-data-refs.cc - vectorizer specific data-refs analysis and
38 manipulations (used by all).
39 - tree-vect-patterns.cc - vectorizable code patterns detector (used by all)
40
41 Here's a poor attempt at illustrating that:
42
43 tree-vectorizer.cc:
44 loop_vect() loop_aware_slp() slp_vect()
45 | / \ /
46 | / \ /
47 tree-vect-loop.cc tree-vect-slp.cc
48 | \ \ / / |
49 | \ \/ / |
50 | \ /\ / |
51 | \ / \ / |
52 tree-vect-stmts.cc tree-vect-data-refs.cc
53 \ /
54 tree-vect-patterns.cc
55 */
56
57 #include "config.h"
58 #include "system.h"
59 #include "coretypes.h"
60 #include "backend.h"
61 #include "tree.h"
62 #include "gimple.h"
63 #include "predict.h"
64 #include "tree-pass.h"
65 #include "ssa.h"
66 #include "cgraph.h"
67 #include "fold-const.h"
68 #include "stor-layout.h"
69 #include "gimple-iterator.h"
70 #include "gimple-walk.h"
71 #include "tree-ssa-loop-manip.h"
72 #include "tree-ssa-loop-niter.h"
73 #include "tree-cfg.h"
74 #include "cfgloop.h"
75 #include "tree-vectorizer.h"
76 #include "tree-ssa-propagate.h"
77 #include "dbgcnt.h"
78 #include "tree-scalar-evolution.h"
79 #include "stringpool.h"
80 #include "attribs.h"
81 #include "gimple-pretty-print.h"
82 #include "opt-problem.h"
83 #include "internal-fn.h"
84 #include "tree-ssa-sccvn.h"
85
86 /* Loop or bb location, with hotness information. */
87 dump_user_location_t vect_location;
88
89 /* auto_purge_vect_location's dtor: reset the vect_location
90 global, to avoid stale location_t values that could reference
91 GC-ed blocks. */
92
~auto_purge_vect_location()93 auto_purge_vect_location::~auto_purge_vect_location ()
94 {
95 vect_location = dump_user_location_t ();
96 }
97
98 /* Dump a cost entry according to args to F. */
99
100 void
dump_stmt_cost(FILE * f,int count,enum vect_cost_for_stmt kind,stmt_vec_info stmt_info,slp_tree node,tree,int misalign,unsigned cost,enum vect_cost_model_location where)101 dump_stmt_cost (FILE *f, int count, enum vect_cost_for_stmt kind,
102 stmt_vec_info stmt_info, slp_tree node, tree,
103 int misalign, unsigned cost,
104 enum vect_cost_model_location where)
105 {
106 if (stmt_info)
107 {
108 print_gimple_expr (f, STMT_VINFO_STMT (stmt_info), 0, TDF_SLIM);
109 fprintf (f, " ");
110 }
111 else if (node)
112 fprintf (f, "node %p ", (void *)node);
113 else
114 fprintf (f, "<unknown> ");
115 fprintf (f, "%d times ", count);
116 const char *ks = "unknown";
117 switch (kind)
118 {
119 case scalar_stmt:
120 ks = "scalar_stmt";
121 break;
122 case scalar_load:
123 ks = "scalar_load";
124 break;
125 case scalar_store:
126 ks = "scalar_store";
127 break;
128 case vector_stmt:
129 ks = "vector_stmt";
130 break;
131 case vector_load:
132 ks = "vector_load";
133 break;
134 case vector_gather_load:
135 ks = "vector_gather_load";
136 break;
137 case unaligned_load:
138 ks = "unaligned_load";
139 break;
140 case unaligned_store:
141 ks = "unaligned_store";
142 break;
143 case vector_store:
144 ks = "vector_store";
145 break;
146 case vector_scatter_store:
147 ks = "vector_scatter_store";
148 break;
149 case vec_to_scalar:
150 ks = "vec_to_scalar";
151 break;
152 case scalar_to_vec:
153 ks = "scalar_to_vec";
154 break;
155 case cond_branch_not_taken:
156 ks = "cond_branch_not_taken";
157 break;
158 case cond_branch_taken:
159 ks = "cond_branch_taken";
160 break;
161 case vec_perm:
162 ks = "vec_perm";
163 break;
164 case vec_promote_demote:
165 ks = "vec_promote_demote";
166 break;
167 case vec_construct:
168 ks = "vec_construct";
169 break;
170 }
171 fprintf (f, "%s ", ks);
172 if (kind == unaligned_load || kind == unaligned_store)
173 fprintf (f, "(misalign %d) ", misalign);
174 fprintf (f, "costs %u ", cost);
175 const char *ws = "unknown";
176 switch (where)
177 {
178 case vect_prologue:
179 ws = "prologue";
180 break;
181 case vect_body:
182 ws = "body";
183 break;
184 case vect_epilogue:
185 ws = "epilogue";
186 break;
187 }
188 fprintf (f, "in %s\n", ws);
189 }
190
191 /* For mapping simduid to vectorization factor. */
192
193 class simduid_to_vf : public free_ptr_hash<simduid_to_vf>
194 {
195 public:
196 unsigned int simduid;
197 poly_uint64 vf;
198
199 /* hash_table support. */
200 static inline hashval_t hash (const simduid_to_vf *);
201 static inline int equal (const simduid_to_vf *, const simduid_to_vf *);
202 };
203
204 inline hashval_t
hash(const simduid_to_vf * p)205 simduid_to_vf::hash (const simduid_to_vf *p)
206 {
207 return p->simduid;
208 }
209
210 inline int
equal(const simduid_to_vf * p1,const simduid_to_vf * p2)211 simduid_to_vf::equal (const simduid_to_vf *p1, const simduid_to_vf *p2)
212 {
213 return p1->simduid == p2->simduid;
214 }
215
216 /* This hash maps the OMP simd array to the corresponding simduid used
217 to index into it. Like thus,
218
219 _7 = GOMP_SIMD_LANE (simduid.0)
220 ...
221 ...
222 D.1737[_7] = stuff;
223
224
225 This hash maps from the OMP simd array (D.1737[]) to DECL_UID of
226 simduid.0. */
227
228 struct simd_array_to_simduid : free_ptr_hash<simd_array_to_simduid>
229 {
230 tree decl;
231 unsigned int simduid;
232
233 /* hash_table support. */
234 static inline hashval_t hash (const simd_array_to_simduid *);
235 static inline int equal (const simd_array_to_simduid *,
236 const simd_array_to_simduid *);
237 };
238
239 inline hashval_t
hash(const simd_array_to_simduid * p)240 simd_array_to_simduid::hash (const simd_array_to_simduid *p)
241 {
242 return DECL_UID (p->decl);
243 }
244
245 inline int
equal(const simd_array_to_simduid * p1,const simd_array_to_simduid * p2)246 simd_array_to_simduid::equal (const simd_array_to_simduid *p1,
247 const simd_array_to_simduid *p2)
248 {
249 return p1->decl == p2->decl;
250 }
251
252 /* Fold IFN_GOMP_SIMD_LANE, IFN_GOMP_SIMD_VF, IFN_GOMP_SIMD_LAST_LANE,
253 into their corresponding constants and remove
254 IFN_GOMP_SIMD_ORDERED_{START,END}. */
255
256 static void
adjust_simduid_builtins(hash_table<simduid_to_vf> * htab,function * fun)257 adjust_simduid_builtins (hash_table<simduid_to_vf> *htab, function *fun)
258 {
259 basic_block bb;
260
261 FOR_EACH_BB_FN (bb, fun)
262 {
263 gimple_stmt_iterator i;
264
265 for (i = gsi_start_bb (bb); !gsi_end_p (i); )
266 {
267 poly_uint64 vf = 1;
268 enum internal_fn ifn;
269 gimple *stmt = gsi_stmt (i);
270 tree t;
271 if (!is_gimple_call (stmt)
272 || !gimple_call_internal_p (stmt))
273 {
274 gsi_next (&i);
275 continue;
276 }
277 ifn = gimple_call_internal_fn (stmt);
278 switch (ifn)
279 {
280 case IFN_GOMP_SIMD_LANE:
281 case IFN_GOMP_SIMD_VF:
282 case IFN_GOMP_SIMD_LAST_LANE:
283 break;
284 case IFN_GOMP_SIMD_ORDERED_START:
285 case IFN_GOMP_SIMD_ORDERED_END:
286 if (integer_onep (gimple_call_arg (stmt, 0)))
287 {
288 enum built_in_function bcode
289 = (ifn == IFN_GOMP_SIMD_ORDERED_START
290 ? BUILT_IN_GOMP_ORDERED_START
291 : BUILT_IN_GOMP_ORDERED_END);
292 gimple *g
293 = gimple_build_call (builtin_decl_explicit (bcode), 0);
294 gimple_move_vops (g, stmt);
295 gsi_replace (&i, g, true);
296 continue;
297 }
298 gsi_remove (&i, true);
299 unlink_stmt_vdef (stmt);
300 continue;
301 default:
302 gsi_next (&i);
303 continue;
304 }
305 tree arg = gimple_call_arg (stmt, 0);
306 gcc_assert (arg != NULL_TREE);
307 gcc_assert (TREE_CODE (arg) == SSA_NAME);
308 simduid_to_vf *p = NULL, data;
309 data.simduid = DECL_UID (SSA_NAME_VAR (arg));
310 /* Need to nullify loop safelen field since it's value is not
311 valid after transformation. */
312 if (bb->loop_father && bb->loop_father->safelen > 0)
313 bb->loop_father->safelen = 0;
314 if (htab)
315 {
316 p = htab->find (&data);
317 if (p)
318 vf = p->vf;
319 }
320 switch (ifn)
321 {
322 case IFN_GOMP_SIMD_VF:
323 t = build_int_cst (unsigned_type_node, vf);
324 break;
325 case IFN_GOMP_SIMD_LANE:
326 t = build_int_cst (unsigned_type_node, 0);
327 break;
328 case IFN_GOMP_SIMD_LAST_LANE:
329 t = gimple_call_arg (stmt, 1);
330 break;
331 default:
332 gcc_unreachable ();
333 }
334 tree lhs = gimple_call_lhs (stmt);
335 if (lhs)
336 replace_uses_by (lhs, t);
337 release_defs (stmt);
338 gsi_remove (&i, true);
339 }
340 }
341 }
342
343 /* Helper structure for note_simd_array_uses. */
344
345 struct note_simd_array_uses_struct
346 {
347 hash_table<simd_array_to_simduid> **htab;
348 unsigned int simduid;
349 };
350
351 /* Callback for note_simd_array_uses, called through walk_gimple_op. */
352
353 static tree
note_simd_array_uses_cb(tree * tp,int * walk_subtrees,void * data)354 note_simd_array_uses_cb (tree *tp, int *walk_subtrees, void *data)
355 {
356 struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
357 struct note_simd_array_uses_struct *ns
358 = (struct note_simd_array_uses_struct *) wi->info;
359
360 if (TYPE_P (*tp))
361 *walk_subtrees = 0;
362 else if (VAR_P (*tp)
363 && lookup_attribute ("omp simd array", DECL_ATTRIBUTES (*tp))
364 && DECL_CONTEXT (*tp) == current_function_decl)
365 {
366 simd_array_to_simduid data;
367 if (!*ns->htab)
368 *ns->htab = new hash_table<simd_array_to_simduid> (15);
369 data.decl = *tp;
370 data.simduid = ns->simduid;
371 simd_array_to_simduid **slot = (*ns->htab)->find_slot (&data, INSERT);
372 if (*slot == NULL)
373 {
374 simd_array_to_simduid *p = XNEW (simd_array_to_simduid);
375 *p = data;
376 *slot = p;
377 }
378 else if ((*slot)->simduid != ns->simduid)
379 (*slot)->simduid = -1U;
380 *walk_subtrees = 0;
381 }
382 return NULL_TREE;
383 }
384
385 /* Find "omp simd array" temporaries and map them to corresponding
386 simduid. */
387
388 static void
note_simd_array_uses(hash_table<simd_array_to_simduid> ** htab,function * fun)389 note_simd_array_uses (hash_table<simd_array_to_simduid> **htab, function *fun)
390 {
391 basic_block bb;
392 gimple_stmt_iterator gsi;
393 struct walk_stmt_info wi;
394 struct note_simd_array_uses_struct ns;
395
396 memset (&wi, 0, sizeof (wi));
397 wi.info = &ns;
398 ns.htab = htab;
399
400 FOR_EACH_BB_FN (bb, fun)
401 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
402 {
403 gimple *stmt = gsi_stmt (gsi);
404 if (!is_gimple_call (stmt) || !gimple_call_internal_p (stmt))
405 continue;
406 switch (gimple_call_internal_fn (stmt))
407 {
408 case IFN_GOMP_SIMD_LANE:
409 case IFN_GOMP_SIMD_VF:
410 case IFN_GOMP_SIMD_LAST_LANE:
411 break;
412 default:
413 continue;
414 }
415 tree lhs = gimple_call_lhs (stmt);
416 if (lhs == NULL_TREE)
417 continue;
418 imm_use_iterator use_iter;
419 gimple *use_stmt;
420 ns.simduid = DECL_UID (SSA_NAME_VAR (gimple_call_arg (stmt, 0)));
421 FOR_EACH_IMM_USE_STMT (use_stmt, use_iter, lhs)
422 if (!is_gimple_debug (use_stmt))
423 walk_gimple_op (use_stmt, note_simd_array_uses_cb, &wi);
424 }
425 }
426
427 /* Shrink arrays with "omp simd array" attribute to the corresponding
428 vectorization factor. */
429
430 static void
shrink_simd_arrays(hash_table<simd_array_to_simduid> * simd_array_to_simduid_htab,hash_table<simduid_to_vf> * simduid_to_vf_htab)431 shrink_simd_arrays
432 (hash_table<simd_array_to_simduid> *simd_array_to_simduid_htab,
433 hash_table<simduid_to_vf> *simduid_to_vf_htab)
434 {
435 for (hash_table<simd_array_to_simduid>::iterator iter
436 = simd_array_to_simduid_htab->begin ();
437 iter != simd_array_to_simduid_htab->end (); ++iter)
438 if ((*iter)->simduid != -1U)
439 {
440 tree decl = (*iter)->decl;
441 poly_uint64 vf = 1;
442 if (simduid_to_vf_htab)
443 {
444 simduid_to_vf *p = NULL, data;
445 data.simduid = (*iter)->simduid;
446 p = simduid_to_vf_htab->find (&data);
447 if (p)
448 vf = p->vf;
449 }
450 tree atype
451 = build_array_type_nelts (TREE_TYPE (TREE_TYPE (decl)), vf);
452 TREE_TYPE (decl) = atype;
453 relayout_decl (decl);
454 }
455
456 delete simd_array_to_simduid_htab;
457 }
458
459 /* Initialize the vec_info with kind KIND_IN and target cost data
460 TARGET_COST_DATA_IN. */
461
vec_info(vec_info::vec_kind kind_in,vec_info_shared * shared_)462 vec_info::vec_info (vec_info::vec_kind kind_in, vec_info_shared *shared_)
463 : kind (kind_in),
464 shared (shared_),
465 stmt_vec_info_ro (false)
466 {
467 stmt_vec_infos.create (50);
468 }
469
~vec_info()470 vec_info::~vec_info ()
471 {
472 for (slp_instance &instance : slp_instances)
473 vect_free_slp_instance (instance);
474
475 free_stmt_vec_infos ();
476 }
477
vec_info_shared()478 vec_info_shared::vec_info_shared ()
479 : n_stmts (0),
480 datarefs (vNULL),
481 datarefs_copy (vNULL),
482 ddrs (vNULL)
483 {
484 }
485
~vec_info_shared()486 vec_info_shared::~vec_info_shared ()
487 {
488 free_data_refs (datarefs);
489 free_dependence_relations (ddrs);
490 datarefs_copy.release ();
491 }
492
493 void
save_datarefs()494 vec_info_shared::save_datarefs ()
495 {
496 if (!flag_checking)
497 return;
498 datarefs_copy.reserve_exact (datarefs.length ());
499 for (unsigned i = 0; i < datarefs.length (); ++i)
500 datarefs_copy.quick_push (*datarefs[i]);
501 }
502
503 void
check_datarefs()504 vec_info_shared::check_datarefs ()
505 {
506 if (!flag_checking)
507 return;
508 gcc_assert (datarefs.length () == datarefs_copy.length ());
509 for (unsigned i = 0; i < datarefs.length (); ++i)
510 if (memcmp (&datarefs_copy[i], datarefs[i],
511 offsetof (data_reference, alt_indices)) != 0)
512 gcc_unreachable ();
513 }
514
515 /* Record that STMT belongs to the vectorizable region. Create and return
516 an associated stmt_vec_info. */
517
518 stmt_vec_info
add_stmt(gimple * stmt)519 vec_info::add_stmt (gimple *stmt)
520 {
521 stmt_vec_info res = new_stmt_vec_info (stmt);
522 set_vinfo_for_stmt (stmt, res);
523 return res;
524 }
525
526 /* Record that STMT belongs to the vectorizable region. Create a new
527 stmt_vec_info and mark VECINFO as being related and return the new
528 stmt_vec_info. */
529
530 stmt_vec_info
add_pattern_stmt(gimple * stmt,stmt_vec_info stmt_info)531 vec_info::add_pattern_stmt (gimple *stmt, stmt_vec_info stmt_info)
532 {
533 stmt_vec_info res = new_stmt_vec_info (stmt);
534 set_vinfo_for_stmt (stmt, res, false);
535 STMT_VINFO_RELATED_STMT (res) = stmt_info;
536 return res;
537 }
538
539 /* If STMT has an associated stmt_vec_info, return that vec_info, otherwise
540 return null. It is safe to call this function on any statement, even if
541 it might not be part of the vectorizable region. */
542
543 stmt_vec_info
lookup_stmt(gimple * stmt)544 vec_info::lookup_stmt (gimple *stmt)
545 {
546 unsigned int uid = gimple_uid (stmt);
547 if (uid > 0 && uid - 1 < stmt_vec_infos.length ())
548 {
549 stmt_vec_info res = stmt_vec_infos[uid - 1];
550 if (res && res->stmt == stmt)
551 return res;
552 }
553 return NULL;
554 }
555
556 /* If NAME is an SSA_NAME and its definition has an associated stmt_vec_info,
557 return that stmt_vec_info, otherwise return null. It is safe to call
558 this on arbitrary operands. */
559
560 stmt_vec_info
lookup_def(tree name)561 vec_info::lookup_def (tree name)
562 {
563 if (TREE_CODE (name) == SSA_NAME
564 && !SSA_NAME_IS_DEFAULT_DEF (name))
565 return lookup_stmt (SSA_NAME_DEF_STMT (name));
566 return NULL;
567 }
568
569 /* See whether there is a single non-debug statement that uses LHS and
570 whether that statement has an associated stmt_vec_info. Return the
571 stmt_vec_info if so, otherwise return null. */
572
573 stmt_vec_info
lookup_single_use(tree lhs)574 vec_info::lookup_single_use (tree lhs)
575 {
576 use_operand_p dummy;
577 gimple *use_stmt;
578 if (single_imm_use (lhs, &dummy, &use_stmt))
579 return lookup_stmt (use_stmt);
580 return NULL;
581 }
582
583 /* Return vectorization information about DR. */
584
585 dr_vec_info *
lookup_dr(data_reference * dr)586 vec_info::lookup_dr (data_reference *dr)
587 {
588 stmt_vec_info stmt_info = lookup_stmt (DR_STMT (dr));
589 /* DR_STMT should never refer to a stmt in a pattern replacement. */
590 gcc_checking_assert (!is_pattern_stmt_p (stmt_info));
591 return STMT_VINFO_DR_INFO (stmt_info->dr_aux.stmt);
592 }
593
594 /* Record that NEW_STMT_INFO now implements the same data reference
595 as OLD_STMT_INFO. */
596
597 void
move_dr(stmt_vec_info new_stmt_info,stmt_vec_info old_stmt_info)598 vec_info::move_dr (stmt_vec_info new_stmt_info, stmt_vec_info old_stmt_info)
599 {
600 gcc_assert (!is_pattern_stmt_p (old_stmt_info));
601 STMT_VINFO_DR_INFO (old_stmt_info)->stmt = new_stmt_info;
602 new_stmt_info->dr_aux = old_stmt_info->dr_aux;
603 STMT_VINFO_DR_WRT_VEC_LOOP (new_stmt_info)
604 = STMT_VINFO_DR_WRT_VEC_LOOP (old_stmt_info);
605 STMT_VINFO_GATHER_SCATTER_P (new_stmt_info)
606 = STMT_VINFO_GATHER_SCATTER_P (old_stmt_info);
607 }
608
609 /* Permanently remove the statement described by STMT_INFO from the
610 function. */
611
612 void
remove_stmt(stmt_vec_info stmt_info)613 vec_info::remove_stmt (stmt_vec_info stmt_info)
614 {
615 gcc_assert (!stmt_info->pattern_stmt_p);
616 set_vinfo_for_stmt (stmt_info->stmt, NULL);
617 unlink_stmt_vdef (stmt_info->stmt);
618 gimple_stmt_iterator si = gsi_for_stmt (stmt_info->stmt);
619 gsi_remove (&si, true);
620 release_defs (stmt_info->stmt);
621 free_stmt_vec_info (stmt_info);
622 }
623
624 /* Replace the statement at GSI by NEW_STMT, both the vectorization
625 information and the function itself. STMT_INFO describes the statement
626 at GSI. */
627
628 void
replace_stmt(gimple_stmt_iterator * gsi,stmt_vec_info stmt_info,gimple * new_stmt)629 vec_info::replace_stmt (gimple_stmt_iterator *gsi, stmt_vec_info stmt_info,
630 gimple *new_stmt)
631 {
632 gimple *old_stmt = stmt_info->stmt;
633 gcc_assert (!stmt_info->pattern_stmt_p && old_stmt == gsi_stmt (*gsi));
634 gimple_set_uid (new_stmt, gimple_uid (old_stmt));
635 stmt_info->stmt = new_stmt;
636 gsi_replace (gsi, new_stmt, true);
637 }
638
639 /* Insert stmts in SEQ on the VEC_INFO region entry. If CONTEXT is
640 not NULL it specifies whether to use the sub-region entry
641 determined by it, currently used for loop vectorization to insert
642 on the inner loop entry vs. the outer loop entry. */
643
644 void
insert_seq_on_entry(stmt_vec_info context,gimple_seq seq)645 vec_info::insert_seq_on_entry (stmt_vec_info context, gimple_seq seq)
646 {
647 if (loop_vec_info loop_vinfo = dyn_cast <loop_vec_info> (this))
648 {
649 class loop *loop = LOOP_VINFO_LOOP (loop_vinfo);
650 basic_block new_bb;
651 edge pe;
652
653 if (context && nested_in_vect_loop_p (loop, context))
654 loop = loop->inner;
655
656 pe = loop_preheader_edge (loop);
657 new_bb = gsi_insert_seq_on_edge_immediate (pe, seq);
658 gcc_assert (!new_bb);
659 }
660 else
661 {
662 bb_vec_info bb_vinfo = as_a <bb_vec_info> (this);
663 gimple_stmt_iterator gsi_region_begin
664 = gsi_after_labels (bb_vinfo->bbs[0]);
665 gsi_insert_seq_before (&gsi_region_begin, seq, GSI_SAME_STMT);
666 }
667 }
668
669 /* Like insert_seq_on_entry but just inserts the single stmt NEW_STMT. */
670
671 void
insert_on_entry(stmt_vec_info context,gimple * new_stmt)672 vec_info::insert_on_entry (stmt_vec_info context, gimple *new_stmt)
673 {
674 gimple_seq seq = NULL;
675 gimple_stmt_iterator gsi = gsi_start (seq);
676 gsi_insert_before_without_update (&gsi, new_stmt, GSI_SAME_STMT);
677 insert_seq_on_entry (context, seq);
678 }
679
680 /* Create and initialize a new stmt_vec_info struct for STMT. */
681
682 stmt_vec_info
new_stmt_vec_info(gimple * stmt)683 vec_info::new_stmt_vec_info (gimple *stmt)
684 {
685 stmt_vec_info res = XCNEW (class _stmt_vec_info);
686 res->stmt = stmt;
687
688 STMT_VINFO_TYPE (res) = undef_vec_info_type;
689 STMT_VINFO_RELEVANT (res) = vect_unused_in_scope;
690 STMT_VINFO_VECTORIZABLE (res) = true;
691 STMT_VINFO_REDUC_TYPE (res) = TREE_CODE_REDUCTION;
692 STMT_VINFO_REDUC_CODE (res) = ERROR_MARK;
693 STMT_VINFO_REDUC_FN (res) = IFN_LAST;
694 STMT_VINFO_REDUC_IDX (res) = -1;
695 STMT_VINFO_SLP_VECT_ONLY (res) = false;
696 STMT_VINFO_SLP_VECT_ONLY_PATTERN (res) = false;
697 STMT_VINFO_VEC_STMTS (res) = vNULL;
698 res->reduc_initial_values = vNULL;
699 res->reduc_scalar_results = vNULL;
700
701 if (is_a <loop_vec_info> (this)
702 && gimple_code (stmt) == GIMPLE_PHI
703 && is_loop_header_bb_p (gimple_bb (stmt)))
704 STMT_VINFO_DEF_TYPE (res) = vect_unknown_def_type;
705 else
706 STMT_VINFO_DEF_TYPE (res) = vect_internal_def;
707
708 STMT_SLP_TYPE (res) = loop_vect;
709
710 /* This is really "uninitialized" until vect_compute_data_ref_alignment. */
711 res->dr_aux.misalignment = DR_MISALIGNMENT_UNINITIALIZED;
712
713 return res;
714 }
715
716 /* Associate STMT with INFO. */
717
718 void
set_vinfo_for_stmt(gimple * stmt,stmt_vec_info info,bool check_ro)719 vec_info::set_vinfo_for_stmt (gimple *stmt, stmt_vec_info info, bool check_ro)
720 {
721 unsigned int uid = gimple_uid (stmt);
722 if (uid == 0)
723 {
724 gcc_assert (!check_ro || !stmt_vec_info_ro);
725 gcc_checking_assert (info);
726 uid = stmt_vec_infos.length () + 1;
727 gimple_set_uid (stmt, uid);
728 stmt_vec_infos.safe_push (info);
729 }
730 else
731 {
732 gcc_checking_assert (info == NULL);
733 stmt_vec_infos[uid - 1] = info;
734 }
735 }
736
737 /* Free the contents of stmt_vec_infos. */
738
739 void
free_stmt_vec_infos(void)740 vec_info::free_stmt_vec_infos (void)
741 {
742 for (stmt_vec_info &info : stmt_vec_infos)
743 if (info != NULL)
744 free_stmt_vec_info (info);
745 stmt_vec_infos.release ();
746 }
747
748 /* Free STMT_INFO. */
749
750 void
free_stmt_vec_info(stmt_vec_info stmt_info)751 vec_info::free_stmt_vec_info (stmt_vec_info stmt_info)
752 {
753 if (stmt_info->pattern_stmt_p)
754 {
755 gimple_set_bb (stmt_info->stmt, NULL);
756 tree lhs = gimple_get_lhs (stmt_info->stmt);
757 if (lhs && TREE_CODE (lhs) == SSA_NAME)
758 release_ssa_name (lhs);
759 }
760
761 stmt_info->reduc_initial_values.release ();
762 stmt_info->reduc_scalar_results.release ();
763 STMT_VINFO_SIMD_CLONE_INFO (stmt_info).release ();
764 STMT_VINFO_VEC_STMTS (stmt_info).release ();
765 free (stmt_info);
766 }
767
768 /* Returns true if S1 dominates S2. */
769
770 bool
vect_stmt_dominates_stmt_p(gimple * s1,gimple * s2)771 vect_stmt_dominates_stmt_p (gimple *s1, gimple *s2)
772 {
773 basic_block bb1 = gimple_bb (s1), bb2 = gimple_bb (s2);
774
775 /* If bb1 is NULL, it should be a GIMPLE_NOP def stmt of an (D)
776 SSA_NAME. Assume it lives at the beginning of function and
777 thus dominates everything. */
778 if (!bb1 || s1 == s2)
779 return true;
780
781 /* If bb2 is NULL, it doesn't dominate any stmt with a bb. */
782 if (!bb2)
783 return false;
784
785 if (bb1 != bb2)
786 return dominated_by_p (CDI_DOMINATORS, bb2, bb1);
787
788 /* PHIs in the same basic block are assumed to be
789 executed all in parallel, if only one stmt is a PHI,
790 it dominates the other stmt in the same basic block. */
791 if (gimple_code (s1) == GIMPLE_PHI)
792 return true;
793
794 if (gimple_code (s2) == GIMPLE_PHI)
795 return false;
796
797 /* Inserted vectorized stmts all have UID 0 while the original stmts
798 in the IL have UID increasing within a BB. Walk from both sides
799 until we find the other stmt or a stmt with UID != 0. */
800 gimple_stmt_iterator gsi1 = gsi_for_stmt (s1);
801 while (gimple_uid (gsi_stmt (gsi1)) == 0)
802 {
803 gsi_next (&gsi1);
804 if (gsi_end_p (gsi1))
805 return false;
806 if (gsi_stmt (gsi1) == s2)
807 return true;
808 }
809 if (gimple_uid (gsi_stmt (gsi1)) == -1u)
810 return false;
811
812 gimple_stmt_iterator gsi2 = gsi_for_stmt (s2);
813 while (gimple_uid (gsi_stmt (gsi2)) == 0)
814 {
815 gsi_prev (&gsi2);
816 if (gsi_end_p (gsi2))
817 return false;
818 if (gsi_stmt (gsi2) == s1)
819 return true;
820 }
821 if (gimple_uid (gsi_stmt (gsi2)) == -1u)
822 return false;
823
824 if (gimple_uid (gsi_stmt (gsi1)) <= gimple_uid (gsi_stmt (gsi2)))
825 return true;
826 return false;
827 }
828
829 /* A helper function to free scev and LOOP niter information, as well as
830 clear loop constraint LOOP_C_FINITE. */
831
832 void
vect_free_loop_info_assumptions(class loop * loop)833 vect_free_loop_info_assumptions (class loop *loop)
834 {
835 scev_reset_htab ();
836 /* We need to explicitly reset upper bound information since they are
837 used even after free_numbers_of_iterations_estimates. */
838 loop->any_upper_bound = false;
839 loop->any_likely_upper_bound = false;
840 free_numbers_of_iterations_estimates (loop);
841 loop_constraint_clear (loop, LOOP_C_FINITE);
842 }
843
844 /* If LOOP has been versioned during ifcvt, return the internal call
845 guarding it. */
846
847 gimple *
vect_loop_vectorized_call(class loop * loop,gcond ** cond)848 vect_loop_vectorized_call (class loop *loop, gcond **cond)
849 {
850 basic_block bb = loop_preheader_edge (loop)->src;
851 gimple *g;
852 do
853 {
854 g = last_stmt (bb);
855 if ((g && gimple_code (g) == GIMPLE_COND)
856 || !single_succ_p (bb))
857 break;
858 if (!single_pred_p (bb))
859 break;
860 bb = single_pred (bb);
861 }
862 while (1);
863 if (g && gimple_code (g) == GIMPLE_COND)
864 {
865 if (cond)
866 *cond = as_a <gcond *> (g);
867 gimple_stmt_iterator gsi = gsi_for_stmt (g);
868 gsi_prev (&gsi);
869 if (!gsi_end_p (gsi))
870 {
871 g = gsi_stmt (gsi);
872 if (gimple_call_internal_p (g, IFN_LOOP_VECTORIZED)
873 && (tree_to_shwi (gimple_call_arg (g, 0)) == loop->num
874 || tree_to_shwi (gimple_call_arg (g, 1)) == loop->num))
875 return g;
876 }
877 }
878 return NULL;
879 }
880
881 /* If LOOP has been versioned during loop distribution, return the gurading
882 internal call. */
883
884 static gimple *
vect_loop_dist_alias_call(class loop * loop,function * fun)885 vect_loop_dist_alias_call (class loop *loop, function *fun)
886 {
887 basic_block bb;
888 basic_block entry;
889 class loop *outer, *orig;
890 gimple_stmt_iterator gsi;
891 gimple *g;
892
893 if (loop->orig_loop_num == 0)
894 return NULL;
895
896 orig = get_loop (fun, loop->orig_loop_num);
897 if (orig == NULL)
898 {
899 /* The original loop is somehow destroyed. Clear the information. */
900 loop->orig_loop_num = 0;
901 return NULL;
902 }
903
904 if (loop != orig)
905 bb = nearest_common_dominator (CDI_DOMINATORS, loop->header, orig->header);
906 else
907 bb = loop_preheader_edge (loop)->src;
908
909 outer = bb->loop_father;
910 entry = ENTRY_BLOCK_PTR_FOR_FN (fun);
911
912 /* Look upward in dominance tree. */
913 for (; bb != entry && flow_bb_inside_loop_p (outer, bb);
914 bb = get_immediate_dominator (CDI_DOMINATORS, bb))
915 {
916 g = last_stmt (bb);
917 if (g == NULL || gimple_code (g) != GIMPLE_COND)
918 continue;
919
920 gsi = gsi_for_stmt (g);
921 gsi_prev (&gsi);
922 if (gsi_end_p (gsi))
923 continue;
924
925 g = gsi_stmt (gsi);
926 /* The guarding internal function call must have the same distribution
927 alias id. */
928 if (gimple_call_internal_p (g, IFN_LOOP_DIST_ALIAS)
929 && (tree_to_shwi (gimple_call_arg (g, 0)) == loop->orig_loop_num))
930 return g;
931 }
932 return NULL;
933 }
934
935 /* Set the uids of all the statements in basic blocks inside loop
936 represented by LOOP_VINFO. LOOP_VECTORIZED_CALL is the internal
937 call guarding the loop which has been if converted. */
938 static void
set_uid_loop_bbs(loop_vec_info loop_vinfo,gimple * loop_vectorized_call,function * fun)939 set_uid_loop_bbs (loop_vec_info loop_vinfo, gimple *loop_vectorized_call,
940 function *fun)
941 {
942 tree arg = gimple_call_arg (loop_vectorized_call, 1);
943 basic_block *bbs;
944 unsigned int i;
945 class loop *scalar_loop = get_loop (fun, tree_to_shwi (arg));
946
947 LOOP_VINFO_SCALAR_LOOP (loop_vinfo) = scalar_loop;
948 gcc_checking_assert (vect_loop_vectorized_call (scalar_loop)
949 == loop_vectorized_call);
950 /* If we are going to vectorize outer loop, prevent vectorization
951 of the inner loop in the scalar loop - either the scalar loop is
952 thrown away, so it is a wasted work, or is used only for
953 a few iterations. */
954 if (scalar_loop->inner)
955 {
956 gimple *g = vect_loop_vectorized_call (scalar_loop->inner);
957 if (g)
958 {
959 arg = gimple_call_arg (g, 0);
960 get_loop (fun, tree_to_shwi (arg))->dont_vectorize = true;
961 fold_loop_internal_call (g, boolean_false_node);
962 }
963 }
964 bbs = get_loop_body (scalar_loop);
965 for (i = 0; i < scalar_loop->num_nodes; i++)
966 {
967 basic_block bb = bbs[i];
968 gimple_stmt_iterator gsi;
969 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
970 {
971 gimple *phi = gsi_stmt (gsi);
972 gimple_set_uid (phi, 0);
973 }
974 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
975 {
976 gimple *stmt = gsi_stmt (gsi);
977 gimple_set_uid (stmt, 0);
978 }
979 }
980 free (bbs);
981 }
982
983 /* Generate vectorized code for LOOP and its epilogues. */
984
985 static void
vect_transform_loops(hash_table<simduid_to_vf> * & simduid_to_vf_htab,loop_p loop,gimple * loop_vectorized_call,function * fun)986 vect_transform_loops (hash_table<simduid_to_vf> *&simduid_to_vf_htab,
987 loop_p loop, gimple *loop_vectorized_call,
988 function *fun)
989 {
990 loop_vec_info loop_vinfo = loop_vec_info_for_loop (loop);
991
992 if (loop_vectorized_call)
993 set_uid_loop_bbs (loop_vinfo, loop_vectorized_call, fun);
994
995 unsigned HOST_WIDE_INT bytes;
996 if (dump_enabled_p ())
997 {
998 if (GET_MODE_SIZE (loop_vinfo->vector_mode).is_constant (&bytes))
999 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, vect_location,
1000 "loop vectorized using %wu byte vectors\n", bytes);
1001 else
1002 dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, vect_location,
1003 "loop vectorized using variable length vectors\n");
1004 }
1005
1006 loop_p new_loop = vect_transform_loop (loop_vinfo,
1007 loop_vectorized_call);
1008 /* Now that the loop has been vectorized, allow it to be unrolled
1009 etc. */
1010 loop->force_vectorize = false;
1011
1012 if (loop->simduid)
1013 {
1014 simduid_to_vf *simduid_to_vf_data = XNEW (simduid_to_vf);
1015 if (!simduid_to_vf_htab)
1016 simduid_to_vf_htab = new hash_table<simduid_to_vf> (15);
1017 simduid_to_vf_data->simduid = DECL_UID (loop->simduid);
1018 simduid_to_vf_data->vf = loop_vinfo->vectorization_factor;
1019 *simduid_to_vf_htab->find_slot (simduid_to_vf_data, INSERT)
1020 = simduid_to_vf_data;
1021 }
1022
1023 /* Epilogue of vectorized loop must be vectorized too. */
1024 if (new_loop)
1025 vect_transform_loops (simduid_to_vf_htab, new_loop, NULL, fun);
1026 }
1027
1028 /* Try to vectorize LOOP. */
1029
1030 static unsigned
try_vectorize_loop_1(hash_table<simduid_to_vf> * & simduid_to_vf_htab,unsigned * num_vectorized_loops,loop_p loop,gimple * loop_vectorized_call,gimple * loop_dist_alias_call,function * fun)1031 try_vectorize_loop_1 (hash_table<simduid_to_vf> *&simduid_to_vf_htab,
1032 unsigned *num_vectorized_loops, loop_p loop,
1033 gimple *loop_vectorized_call,
1034 gimple *loop_dist_alias_call,
1035 function *fun)
1036 {
1037 unsigned ret = 0;
1038 vec_info_shared shared;
1039 auto_purge_vect_location sentinel;
1040 vect_location = find_loop_location (loop);
1041
1042 if (LOCATION_LOCUS (vect_location.get_location_t ()) != UNKNOWN_LOCATION
1043 && dump_enabled_p ())
1044 dump_printf (MSG_NOTE | MSG_PRIORITY_INTERNALS,
1045 "\nAnalyzing loop at %s:%d\n",
1046 LOCATION_FILE (vect_location.get_location_t ()),
1047 LOCATION_LINE (vect_location.get_location_t ()));
1048
1049 /* Try to analyze the loop, retaining an opt_problem if dump_enabled_p. */
1050 opt_loop_vec_info loop_vinfo = vect_analyze_loop (loop, &shared);
1051 loop->aux = loop_vinfo;
1052
1053 if (!loop_vinfo)
1054 if (dump_enabled_p ())
1055 if (opt_problem *problem = loop_vinfo.get_problem ())
1056 {
1057 dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
1058 "couldn't vectorize loop\n");
1059 problem->emit_and_clear ();
1060 }
1061
1062 if (!loop_vinfo || !LOOP_VINFO_VECTORIZABLE_P (loop_vinfo))
1063 {
1064 /* Free existing information if loop is analyzed with some
1065 assumptions. */
1066 if (loop_constraint_set_p (loop, LOOP_C_FINITE))
1067 vect_free_loop_info_assumptions (loop);
1068
1069 /* If we applied if-conversion then try to vectorize the
1070 BB of innermost loops.
1071 ??? Ideally BB vectorization would learn to vectorize
1072 control flow by applying if-conversion on-the-fly, the
1073 following retains the if-converted loop body even when
1074 only non-if-converted parts took part in BB vectorization. */
1075 if (flag_tree_slp_vectorize != 0
1076 && loop_vectorized_call
1077 && ! loop->inner)
1078 {
1079 basic_block bb = loop->header;
1080 bool require_loop_vectorize = false;
1081 for (gimple_stmt_iterator gsi = gsi_start_bb (bb);
1082 !gsi_end_p (gsi); gsi_next (&gsi))
1083 {
1084 gimple *stmt = gsi_stmt (gsi);
1085 gcall *call = dyn_cast <gcall *> (stmt);
1086 if (call && gimple_call_internal_p (call))
1087 {
1088 internal_fn ifn = gimple_call_internal_fn (call);
1089 if (ifn == IFN_MASK_LOAD || ifn == IFN_MASK_STORE
1090 /* Don't keep the if-converted parts when the ifn with
1091 specifc type is not supported by the backend. */
1092 || (direct_internal_fn_p (ifn)
1093 && !direct_internal_fn_supported_p
1094 (call, OPTIMIZE_FOR_SPEED)))
1095 {
1096 require_loop_vectorize = true;
1097 break;
1098 }
1099 }
1100 gimple_set_uid (stmt, -1);
1101 gimple_set_visited (stmt, false);
1102 }
1103 if (!require_loop_vectorize)
1104 {
1105 tree arg = gimple_call_arg (loop_vectorized_call, 1);
1106 class loop *scalar_loop = get_loop (fun, tree_to_shwi (arg));
1107 if (vect_slp_if_converted_bb (bb, scalar_loop))
1108 {
1109 fold_loop_internal_call (loop_vectorized_call,
1110 boolean_true_node);
1111 loop_vectorized_call = NULL;
1112 ret |= TODO_cleanup_cfg | TODO_update_ssa_only_virtuals;
1113 }
1114 }
1115 }
1116 /* If outer loop vectorization fails for LOOP_VECTORIZED guarded
1117 loop, don't vectorize its inner loop; we'll attempt to
1118 vectorize LOOP_VECTORIZED guarded inner loop of the scalar
1119 loop version. */
1120 if (loop_vectorized_call && loop->inner)
1121 loop->inner->dont_vectorize = true;
1122 return ret;
1123 }
1124
1125 if (!dbg_cnt (vect_loop))
1126 {
1127 /* Free existing information if loop is analyzed with some
1128 assumptions. */
1129 if (loop_constraint_set_p (loop, LOOP_C_FINITE))
1130 vect_free_loop_info_assumptions (loop);
1131 return ret;
1132 }
1133
1134 (*num_vectorized_loops)++;
1135 /* Transform LOOP and its epilogues. */
1136 vect_transform_loops (simduid_to_vf_htab, loop, loop_vectorized_call, fun);
1137
1138 if (loop_vectorized_call)
1139 {
1140 fold_loop_internal_call (loop_vectorized_call, boolean_true_node);
1141 ret |= TODO_cleanup_cfg;
1142 }
1143 if (loop_dist_alias_call)
1144 {
1145 tree value = gimple_call_arg (loop_dist_alias_call, 1);
1146 fold_loop_internal_call (loop_dist_alias_call, value);
1147 ret |= TODO_cleanup_cfg;
1148 }
1149
1150 return ret;
1151 }
1152
1153 /* Try to vectorize LOOP. */
1154
1155 static unsigned
try_vectorize_loop(hash_table<simduid_to_vf> * & simduid_to_vf_htab,unsigned * num_vectorized_loops,loop_p loop,function * fun)1156 try_vectorize_loop (hash_table<simduid_to_vf> *&simduid_to_vf_htab,
1157 unsigned *num_vectorized_loops, loop_p loop,
1158 function *fun)
1159 {
1160 if (!((flag_tree_loop_vectorize
1161 && optimize_loop_nest_for_speed_p (loop))
1162 || loop->force_vectorize))
1163 return 0;
1164
1165 return try_vectorize_loop_1 (simduid_to_vf_htab, num_vectorized_loops, loop,
1166 vect_loop_vectorized_call (loop),
1167 vect_loop_dist_alias_call (loop, fun), fun);
1168 }
1169
1170
1171 /* Loop autovectorization. */
1172
1173 namespace {
1174
1175 const pass_data pass_data_vectorize =
1176 {
1177 GIMPLE_PASS, /* type */
1178 "vect", /* name */
1179 OPTGROUP_LOOP | OPTGROUP_VEC, /* optinfo_flags */
1180 TV_TREE_VECTORIZATION, /* tv_id */
1181 ( PROP_cfg | PROP_ssa ), /* properties_required */
1182 0, /* properties_provided */
1183 0, /* properties_destroyed */
1184 0, /* todo_flags_start */
1185 0, /* todo_flags_finish */
1186 };
1187
1188 class pass_vectorize : public gimple_opt_pass
1189 {
1190 public:
pass_vectorize(gcc::context * ctxt)1191 pass_vectorize (gcc::context *ctxt)
1192 : gimple_opt_pass (pass_data_vectorize, ctxt)
1193 {}
1194
1195 /* opt_pass methods: */
gate(function * fun)1196 virtual bool gate (function *fun)
1197 {
1198 return flag_tree_loop_vectorize || fun->has_force_vectorize_loops;
1199 }
1200
1201 virtual unsigned int execute (function *);
1202
1203 }; // class pass_vectorize
1204
1205 /* Function vectorize_loops.
1206
1207 Entry point to loop vectorization phase. */
1208
1209 unsigned
execute(function * fun)1210 pass_vectorize::execute (function *fun)
1211 {
1212 unsigned int i;
1213 unsigned int num_vectorized_loops = 0;
1214 unsigned int vect_loops_num;
1215 hash_table<simduid_to_vf> *simduid_to_vf_htab = NULL;
1216 hash_table<simd_array_to_simduid> *simd_array_to_simduid_htab = NULL;
1217 bool any_ifcvt_loops = false;
1218 unsigned ret = 0;
1219
1220 vect_loops_num = number_of_loops (fun);
1221
1222 /* Bail out if there are no loops. */
1223 if (vect_loops_num <= 1)
1224 return 0;
1225
1226 vect_slp_init ();
1227
1228 if (fun->has_simduid_loops)
1229 note_simd_array_uses (&simd_array_to_simduid_htab, fun);
1230
1231 /* ----------- Analyze loops. ----------- */
1232
1233 /* If some loop was duplicated, it gets bigger number
1234 than all previously defined loops. This fact allows us to run
1235 only over initial loops skipping newly generated ones. */
1236 for (auto loop : loops_list (fun, 0))
1237 if (loop->dont_vectorize)
1238 {
1239 any_ifcvt_loops = true;
1240 /* If-conversion sometimes versions both the outer loop
1241 (for the case when outer loop vectorization might be
1242 desirable) as well as the inner loop in the scalar version
1243 of the loop. So we have:
1244 if (LOOP_VECTORIZED (1, 3))
1245 {
1246 loop1
1247 loop2
1248 }
1249 else
1250 loop3 (copy of loop1)
1251 if (LOOP_VECTORIZED (4, 5))
1252 loop4 (copy of loop2)
1253 else
1254 loop5 (copy of loop4)
1255 If loops' iteration gives us loop3 first (which has
1256 dont_vectorize set), make sure to process loop1 before loop4;
1257 so that we can prevent vectorization of loop4 if loop1
1258 is successfully vectorized. */
1259 if (loop->inner)
1260 {
1261 gimple *loop_vectorized_call
1262 = vect_loop_vectorized_call (loop);
1263 if (loop_vectorized_call
1264 && vect_loop_vectorized_call (loop->inner))
1265 {
1266 tree arg = gimple_call_arg (loop_vectorized_call, 0);
1267 class loop *vector_loop
1268 = get_loop (fun, tree_to_shwi (arg));
1269 if (vector_loop && vector_loop != loop)
1270 {
1271 /* Make sure we don't vectorize it twice. */
1272 vector_loop->dont_vectorize = true;
1273 ret |= try_vectorize_loop (simduid_to_vf_htab,
1274 &num_vectorized_loops,
1275 vector_loop, fun);
1276 }
1277 }
1278 }
1279 }
1280 else
1281 ret |= try_vectorize_loop (simduid_to_vf_htab, &num_vectorized_loops,
1282 loop, fun);
1283
1284 vect_location = dump_user_location_t ();
1285
1286 statistics_counter_event (fun, "Vectorized loops", num_vectorized_loops);
1287 if (dump_enabled_p ()
1288 || (num_vectorized_loops > 0 && dump_enabled_p ()))
1289 dump_printf_loc (MSG_NOTE, vect_location,
1290 "vectorized %u loops in function.\n",
1291 num_vectorized_loops);
1292
1293 /* ----------- Finalize. ----------- */
1294
1295 if (any_ifcvt_loops)
1296 for (i = 1; i < number_of_loops (fun); i++)
1297 {
1298 class loop *loop = get_loop (fun, i);
1299 if (loop && loop->dont_vectorize)
1300 {
1301 gimple *g = vect_loop_vectorized_call (loop);
1302 if (g)
1303 {
1304 fold_loop_internal_call (g, boolean_false_node);
1305 ret |= TODO_cleanup_cfg;
1306 g = NULL;
1307 }
1308 else
1309 g = vect_loop_dist_alias_call (loop, fun);
1310
1311 if (g)
1312 {
1313 fold_loop_internal_call (g, boolean_false_node);
1314 ret |= TODO_cleanup_cfg;
1315 }
1316 }
1317 }
1318
1319 /* Fold IFN_GOMP_SIMD_{VF,LANE,LAST_LANE,ORDERED_{START,END}} builtins. */
1320 if (fun->has_simduid_loops)
1321 {
1322 adjust_simduid_builtins (simduid_to_vf_htab, fun);
1323 /* Avoid stale SCEV cache entries for the SIMD_LANE defs. */
1324 scev_reset ();
1325 }
1326 /* Shrink any "omp array simd" temporary arrays to the
1327 actual vectorization factors. */
1328 if (simd_array_to_simduid_htab)
1329 shrink_simd_arrays (simd_array_to_simduid_htab, simduid_to_vf_htab);
1330 delete simduid_to_vf_htab;
1331 fun->has_simduid_loops = false;
1332
1333 if (num_vectorized_loops > 0)
1334 {
1335 /* If we vectorized any loop only virtual SSA form needs to be updated.
1336 ??? Also while we try hard to update loop-closed SSA form we fail
1337 to properly do this in some corner-cases (see PR56286). */
1338 rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa_only_virtuals);
1339 ret |= TODO_cleanup_cfg;
1340 }
1341
1342 for (i = 1; i < number_of_loops (fun); i++)
1343 {
1344 loop_vec_info loop_vinfo;
1345 bool has_mask_store;
1346
1347 class loop *loop = get_loop (fun, i);
1348 if (!loop || !loop->aux)
1349 continue;
1350 loop_vinfo = (loop_vec_info) loop->aux;
1351 has_mask_store = LOOP_VINFO_HAS_MASK_STORE (loop_vinfo);
1352 delete loop_vinfo;
1353 if (has_mask_store
1354 && targetm.vectorize.empty_mask_is_expensive (IFN_MASK_STORE))
1355 optimize_mask_stores (loop);
1356
1357 auto_bitmap exit_bbs;
1358 /* Perform local CSE, this esp. helps because we emit code for
1359 predicates that need to be shared for optimal predicate usage.
1360 However reassoc will re-order them and prevent CSE from working
1361 as it should. CSE only the loop body, not the entry. */
1362 bitmap_set_bit (exit_bbs, single_exit (loop)->dest->index);
1363
1364 edge entry = EDGE_PRED (loop_preheader_edge (loop)->src, 0);
1365 do_rpo_vn (fun, entry, exit_bbs);
1366
1367 loop->aux = NULL;
1368 }
1369
1370 vect_slp_fini ();
1371
1372 return ret;
1373 }
1374
1375 } // anon namespace
1376
1377 gimple_opt_pass *
make_pass_vectorize(gcc::context * ctxt)1378 make_pass_vectorize (gcc::context *ctxt)
1379 {
1380 return new pass_vectorize (ctxt);
1381 }
1382
1383 /* Entry point to the simduid cleanup pass. */
1384
1385 namespace {
1386
1387 const pass_data pass_data_simduid_cleanup =
1388 {
1389 GIMPLE_PASS, /* type */
1390 "simduid", /* name */
1391 OPTGROUP_NONE, /* optinfo_flags */
1392 TV_NONE, /* tv_id */
1393 ( PROP_ssa | PROP_cfg ), /* properties_required */
1394 0, /* properties_provided */
1395 0, /* properties_destroyed */
1396 0, /* todo_flags_start */
1397 0, /* todo_flags_finish */
1398 };
1399
1400 class pass_simduid_cleanup : public gimple_opt_pass
1401 {
1402 public:
pass_simduid_cleanup(gcc::context * ctxt)1403 pass_simduid_cleanup (gcc::context *ctxt)
1404 : gimple_opt_pass (pass_data_simduid_cleanup, ctxt)
1405 {}
1406
1407 /* opt_pass methods: */
clone()1408 opt_pass * clone () { return new pass_simduid_cleanup (m_ctxt); }
gate(function * fun)1409 virtual bool gate (function *fun) { return fun->has_simduid_loops; }
1410 virtual unsigned int execute (function *);
1411
1412 }; // class pass_simduid_cleanup
1413
1414 unsigned int
execute(function * fun)1415 pass_simduid_cleanup::execute (function *fun)
1416 {
1417 hash_table<simd_array_to_simduid> *simd_array_to_simduid_htab = NULL;
1418
1419 note_simd_array_uses (&simd_array_to_simduid_htab, fun);
1420
1421 /* Fold IFN_GOMP_SIMD_{VF,LANE,LAST_LANE,ORDERED_{START,END}} builtins. */
1422 adjust_simduid_builtins (NULL, fun);
1423
1424 /* Shrink any "omp array simd" temporary arrays to the
1425 actual vectorization factors. */
1426 if (simd_array_to_simduid_htab)
1427 shrink_simd_arrays (simd_array_to_simduid_htab, NULL);
1428 fun->has_simduid_loops = false;
1429 return 0;
1430 }
1431
1432 } // anon namespace
1433
1434 gimple_opt_pass *
make_pass_simduid_cleanup(gcc::context * ctxt)1435 make_pass_simduid_cleanup (gcc::context *ctxt)
1436 {
1437 return new pass_simduid_cleanup (ctxt);
1438 }
1439
1440
1441 /* Entry point to basic block SLP phase. */
1442
1443 namespace {
1444
1445 const pass_data pass_data_slp_vectorize =
1446 {
1447 GIMPLE_PASS, /* type */
1448 "slp", /* name */
1449 OPTGROUP_LOOP | OPTGROUP_VEC, /* optinfo_flags */
1450 TV_TREE_SLP_VECTORIZATION, /* tv_id */
1451 ( PROP_ssa | PROP_cfg ), /* properties_required */
1452 0, /* properties_provided */
1453 0, /* properties_destroyed */
1454 0, /* todo_flags_start */
1455 TODO_update_ssa, /* todo_flags_finish */
1456 };
1457
1458 class pass_slp_vectorize : public gimple_opt_pass
1459 {
1460 public:
pass_slp_vectorize(gcc::context * ctxt)1461 pass_slp_vectorize (gcc::context *ctxt)
1462 : gimple_opt_pass (pass_data_slp_vectorize, ctxt)
1463 {}
1464
1465 /* opt_pass methods: */
clone()1466 opt_pass * clone () { return new pass_slp_vectorize (m_ctxt); }
gate(function *)1467 virtual bool gate (function *) { return flag_tree_slp_vectorize != 0; }
1468 virtual unsigned int execute (function *);
1469
1470 }; // class pass_slp_vectorize
1471
1472 unsigned int
execute(function * fun)1473 pass_slp_vectorize::execute (function *fun)
1474 {
1475 auto_purge_vect_location sentinel;
1476 basic_block bb;
1477
1478 bool in_loop_pipeline = scev_initialized_p ();
1479 if (!in_loop_pipeline)
1480 {
1481 loop_optimizer_init (LOOPS_NORMAL);
1482 scev_initialize ();
1483 }
1484
1485 /* Mark all stmts as not belonging to the current region and unvisited. */
1486 FOR_EACH_BB_FN (bb, fun)
1487 {
1488 for (gphi_iterator gsi = gsi_start_phis (bb); !gsi_end_p (gsi);
1489 gsi_next (&gsi))
1490 {
1491 gphi *stmt = gsi.phi ();
1492 gimple_set_uid (stmt, -1);
1493 gimple_set_visited (stmt, false);
1494 }
1495 for (gimple_stmt_iterator gsi = gsi_start_bb (bb); !gsi_end_p (gsi);
1496 gsi_next (&gsi))
1497 {
1498 gimple *stmt = gsi_stmt (gsi);
1499 gimple_set_uid (stmt, -1);
1500 gimple_set_visited (stmt, false);
1501 }
1502 }
1503
1504 vect_slp_init ();
1505
1506 vect_slp_function (fun);
1507
1508 vect_slp_fini ();
1509
1510 if (!in_loop_pipeline)
1511 {
1512 scev_finalize ();
1513 loop_optimizer_finalize ();
1514 }
1515
1516 return 0;
1517 }
1518
1519 } // anon namespace
1520
1521 gimple_opt_pass *
make_pass_slp_vectorize(gcc::context * ctxt)1522 make_pass_slp_vectorize (gcc::context *ctxt)
1523 {
1524 return new pass_slp_vectorize (ctxt);
1525 }
1526
1527
1528 /* Increase alignment of global arrays to improve vectorization potential.
1529 TODO:
1530 - Consider also structs that have an array field.
1531 - Use ipa analysis to prune arrays that can't be vectorized?
1532 This should involve global alignment analysis and in the future also
1533 array padding. */
1534
1535 static unsigned get_vec_alignment_for_type (tree);
1536 static hash_map<tree, unsigned> *type_align_map;
1537
1538 /* Return alignment of array's vector type corresponding to scalar type.
1539 0 if no vector type exists. */
1540 static unsigned
get_vec_alignment_for_array_type(tree type)1541 get_vec_alignment_for_array_type (tree type)
1542 {
1543 gcc_assert (TREE_CODE (type) == ARRAY_TYPE);
1544 poly_uint64 array_size, vector_size;
1545
1546 tree scalar_type = strip_array_types (type);
1547 tree vectype = get_related_vectype_for_scalar_type (VOIDmode, scalar_type);
1548 if (!vectype
1549 || !poly_int_tree_p (TYPE_SIZE (type), &array_size)
1550 || !poly_int_tree_p (TYPE_SIZE (vectype), &vector_size)
1551 || maybe_lt (array_size, vector_size))
1552 return 0;
1553
1554 return TYPE_ALIGN (vectype);
1555 }
1556
1557 /* Return alignment of field having maximum alignment of vector type
1558 corresponding to it's scalar type. For now, we only consider fields whose
1559 offset is a multiple of it's vector alignment.
1560 0 if no suitable field is found. */
1561 static unsigned
get_vec_alignment_for_record_type(tree type)1562 get_vec_alignment_for_record_type (tree type)
1563 {
1564 gcc_assert (TREE_CODE (type) == RECORD_TYPE);
1565
1566 unsigned max_align = 0, alignment;
1567 HOST_WIDE_INT offset;
1568 tree offset_tree;
1569
1570 if (TYPE_PACKED (type))
1571 return 0;
1572
1573 unsigned *slot = type_align_map->get (type);
1574 if (slot)
1575 return *slot;
1576
1577 for (tree field = first_field (type);
1578 field != NULL_TREE;
1579 field = DECL_CHAIN (field))
1580 {
1581 /* Skip if not FIELD_DECL or if alignment is set by user. */
1582 if (TREE_CODE (field) != FIELD_DECL
1583 || DECL_USER_ALIGN (field)
1584 || DECL_ARTIFICIAL (field))
1585 continue;
1586
1587 /* We don't need to process the type further if offset is variable,
1588 since the offsets of remaining members will also be variable. */
1589 if (TREE_CODE (DECL_FIELD_OFFSET (field)) != INTEGER_CST
1590 || TREE_CODE (DECL_FIELD_BIT_OFFSET (field)) != INTEGER_CST)
1591 break;
1592
1593 /* Similarly stop processing the type if offset_tree
1594 does not fit in unsigned HOST_WIDE_INT. */
1595 offset_tree = bit_position (field);
1596 if (!tree_fits_uhwi_p (offset_tree))
1597 break;
1598
1599 offset = tree_to_uhwi (offset_tree);
1600 alignment = get_vec_alignment_for_type (TREE_TYPE (field));
1601
1602 /* Get maximum alignment of vectorized field/array among those members
1603 whose offset is multiple of the vector alignment. */
1604 if (alignment
1605 && (offset % alignment == 0)
1606 && (alignment > max_align))
1607 max_align = alignment;
1608 }
1609
1610 type_align_map->put (type, max_align);
1611 return max_align;
1612 }
1613
1614 /* Return alignment of vector type corresponding to decl's scalar type
1615 or 0 if it doesn't exist or the vector alignment is lesser than
1616 decl's alignment. */
1617 static unsigned
get_vec_alignment_for_type(tree type)1618 get_vec_alignment_for_type (tree type)
1619 {
1620 if (type == NULL_TREE)
1621 return 0;
1622
1623 gcc_assert (TYPE_P (type));
1624
1625 static unsigned alignment = 0;
1626 switch (TREE_CODE (type))
1627 {
1628 case ARRAY_TYPE:
1629 alignment = get_vec_alignment_for_array_type (type);
1630 break;
1631 case RECORD_TYPE:
1632 alignment = get_vec_alignment_for_record_type (type);
1633 break;
1634 default:
1635 alignment = 0;
1636 break;
1637 }
1638
1639 return (alignment > TYPE_ALIGN (type)) ? alignment : 0;
1640 }
1641
1642 /* Entry point to increase_alignment pass. */
1643 static unsigned int
increase_alignment(void)1644 increase_alignment (void)
1645 {
1646 varpool_node *vnode;
1647
1648 vect_location = dump_user_location_t ();
1649 type_align_map = new hash_map<tree, unsigned>;
1650
1651 /* Increase the alignment of all global arrays for vectorization. */
1652 FOR_EACH_DEFINED_VARIABLE (vnode)
1653 {
1654 tree decl = vnode->decl;
1655 unsigned int alignment;
1656
1657 if ((decl_in_symtab_p (decl)
1658 && !symtab_node::get (decl)->can_increase_alignment_p ())
1659 || DECL_USER_ALIGN (decl) || DECL_ARTIFICIAL (decl))
1660 continue;
1661
1662 alignment = get_vec_alignment_for_type (TREE_TYPE (decl));
1663 if (alignment && vect_can_force_dr_alignment_p (decl, alignment))
1664 {
1665 vnode->increase_alignment (alignment);
1666 if (dump_enabled_p ())
1667 dump_printf (MSG_NOTE, "Increasing alignment of decl: %T\n", decl);
1668 }
1669 }
1670
1671 delete type_align_map;
1672 return 0;
1673 }
1674
1675
1676 namespace {
1677
1678 const pass_data pass_data_ipa_increase_alignment =
1679 {
1680 SIMPLE_IPA_PASS, /* type */
1681 "increase_alignment", /* name */
1682 OPTGROUP_LOOP | OPTGROUP_VEC, /* optinfo_flags */
1683 TV_IPA_OPT, /* tv_id */
1684 0, /* properties_required */
1685 0, /* properties_provided */
1686 0, /* properties_destroyed */
1687 0, /* todo_flags_start */
1688 0, /* todo_flags_finish */
1689 };
1690
1691 class pass_ipa_increase_alignment : public simple_ipa_opt_pass
1692 {
1693 public:
pass_ipa_increase_alignment(gcc::context * ctxt)1694 pass_ipa_increase_alignment (gcc::context *ctxt)
1695 : simple_ipa_opt_pass (pass_data_ipa_increase_alignment, ctxt)
1696 {}
1697
1698 /* opt_pass methods: */
gate(function *)1699 virtual bool gate (function *)
1700 {
1701 return flag_section_anchors && flag_tree_loop_vectorize;
1702 }
1703
execute(function *)1704 virtual unsigned int execute (function *) { return increase_alignment (); }
1705
1706 }; // class pass_ipa_increase_alignment
1707
1708 } // anon namespace
1709
1710 simple_ipa_opt_pass *
make_pass_ipa_increase_alignment(gcc::context * ctxt)1711 make_pass_ipa_increase_alignment (gcc::context *ctxt)
1712 {
1713 return new pass_ipa_increase_alignment (ctxt);
1714 }
1715
1716 /* If the condition represented by T is a comparison or the SSA name
1717 result of a comparison, extract the comparison's operands. Represent
1718 T as NE_EXPR <T, 0> otherwise. */
1719
1720 void
get_cond_ops_from_tree(tree t)1721 scalar_cond_masked_key::get_cond_ops_from_tree (tree t)
1722 {
1723 if (TREE_CODE_CLASS (TREE_CODE (t)) == tcc_comparison)
1724 {
1725 this->code = TREE_CODE (t);
1726 this->op0 = TREE_OPERAND (t, 0);
1727 this->op1 = TREE_OPERAND (t, 1);
1728 this->inverted_p = false;
1729 return;
1730 }
1731
1732 if (TREE_CODE (t) == SSA_NAME)
1733 if (gassign *stmt = dyn_cast<gassign *> (SSA_NAME_DEF_STMT (t)))
1734 {
1735 tree_code code = gimple_assign_rhs_code (stmt);
1736 if (TREE_CODE_CLASS (code) == tcc_comparison)
1737 {
1738 this->code = code;
1739 this->op0 = gimple_assign_rhs1 (stmt);
1740 this->op1 = gimple_assign_rhs2 (stmt);
1741 this->inverted_p = false;
1742 return;
1743 }
1744 else if (code == BIT_NOT_EXPR)
1745 {
1746 tree n_op = gimple_assign_rhs1 (stmt);
1747 if ((stmt = dyn_cast<gassign *> (SSA_NAME_DEF_STMT (n_op))))
1748 {
1749 code = gimple_assign_rhs_code (stmt);
1750 if (TREE_CODE_CLASS (code) == tcc_comparison)
1751 {
1752 this->code = code;
1753 this->op0 = gimple_assign_rhs1 (stmt);
1754 this->op1 = gimple_assign_rhs2 (stmt);
1755 this->inverted_p = true;
1756 return;
1757 }
1758 }
1759 }
1760 }
1761
1762 this->code = NE_EXPR;
1763 this->op0 = t;
1764 this->op1 = build_zero_cst (TREE_TYPE (t));
1765 this->inverted_p = false;
1766 }
1767
1768 /* See the comment above the declaration for details. */
1769
1770 unsigned int
add_stmt_cost(int count,vect_cost_for_stmt kind,stmt_vec_info stmt_info,slp_tree,tree vectype,int misalign,vect_cost_model_location where)1771 vector_costs::add_stmt_cost (int count, vect_cost_for_stmt kind,
1772 stmt_vec_info stmt_info, slp_tree,
1773 tree vectype, int misalign,
1774 vect_cost_model_location where)
1775 {
1776 unsigned int cost
1777 = builtin_vectorization_cost (kind, vectype, misalign) * count;
1778 return record_stmt_cost (stmt_info, where, cost);
1779 }
1780
1781 /* See the comment above the declaration for details. */
1782
1783 void
finish_cost(const vector_costs *)1784 vector_costs::finish_cost (const vector_costs *)
1785 {
1786 gcc_assert (!m_finished);
1787 m_finished = true;
1788 }
1789
1790 /* Record a base cost of COST units against WHERE. If STMT_INFO is
1791 nonnull, use it to adjust the cost based on execution frequency
1792 (where appropriate). */
1793
1794 unsigned int
record_stmt_cost(stmt_vec_info stmt_info,vect_cost_model_location where,unsigned int cost)1795 vector_costs::record_stmt_cost (stmt_vec_info stmt_info,
1796 vect_cost_model_location where,
1797 unsigned int cost)
1798 {
1799 cost = adjust_cost_for_freq (stmt_info, where, cost);
1800 m_costs[where] += cost;
1801 return cost;
1802 }
1803
1804 /* COST is the base cost we have calculated for an operation in location WHERE.
1805 If STMT_INFO is nonnull, use it to adjust the cost based on execution
1806 frequency (where appropriate). Return the adjusted cost. */
1807
1808 unsigned int
adjust_cost_for_freq(stmt_vec_info stmt_info,vect_cost_model_location where,unsigned int cost)1809 vector_costs::adjust_cost_for_freq (stmt_vec_info stmt_info,
1810 vect_cost_model_location where,
1811 unsigned int cost)
1812 {
1813 /* Statements in an inner loop relative to the loop being
1814 vectorized are weighted more heavily. The value here is
1815 arbitrary and could potentially be improved with analysis. */
1816 if (where == vect_body
1817 && stmt_info
1818 && stmt_in_inner_loop_p (m_vinfo, stmt_info))
1819 {
1820 loop_vec_info loop_vinfo = as_a<loop_vec_info> (m_vinfo);
1821 cost *= LOOP_VINFO_INNER_LOOP_COST_FACTOR (loop_vinfo);
1822 }
1823 return cost;
1824 }
1825
1826 /* See the comment above the declaration for details. */
1827
1828 bool
better_main_loop_than_p(const vector_costs * other) const1829 vector_costs::better_main_loop_than_p (const vector_costs *other) const
1830 {
1831 int diff = compare_inside_loop_cost (other);
1832 if (diff != 0)
1833 return diff < 0;
1834
1835 /* If there's nothing to choose between the loop bodies, see whether
1836 there's a difference in the prologue and epilogue costs. */
1837 diff = compare_outside_loop_cost (other);
1838 if (diff != 0)
1839 return diff < 0;
1840
1841 return false;
1842 }
1843
1844
1845 /* See the comment above the declaration for details. */
1846
1847 bool
better_epilogue_loop_than_p(const vector_costs * other,loop_vec_info main_loop) const1848 vector_costs::better_epilogue_loop_than_p (const vector_costs *other,
1849 loop_vec_info main_loop) const
1850 {
1851 loop_vec_info this_loop_vinfo = as_a<loop_vec_info> (this->m_vinfo);
1852 loop_vec_info other_loop_vinfo = as_a<loop_vec_info> (other->m_vinfo);
1853
1854 poly_int64 this_vf = LOOP_VINFO_VECT_FACTOR (this_loop_vinfo);
1855 poly_int64 other_vf = LOOP_VINFO_VECT_FACTOR (other_loop_vinfo);
1856
1857 poly_uint64 main_poly_vf = LOOP_VINFO_VECT_FACTOR (main_loop);
1858 unsigned HOST_WIDE_INT main_vf;
1859 unsigned HOST_WIDE_INT other_factor, this_factor, other_cost, this_cost;
1860 /* If we can determine how many iterations are left for the epilogue
1861 loop, that is if both the main loop's vectorization factor and number
1862 of iterations are constant, then we use them to calculate the cost of
1863 the epilogue loop together with a 'likely value' for the epilogues
1864 vectorization factor. Otherwise we use the main loop's vectorization
1865 factor and the maximum poly value for the epilogue's. If the target
1866 has not provided with a sensible upper bound poly vectorization
1867 factors are likely to be favored over constant ones. */
1868 if (main_poly_vf.is_constant (&main_vf)
1869 && LOOP_VINFO_NITERS_KNOWN_P (main_loop))
1870 {
1871 unsigned HOST_WIDE_INT niters
1872 = LOOP_VINFO_INT_NITERS (main_loop) % main_vf;
1873 HOST_WIDE_INT other_likely_vf
1874 = estimated_poly_value (other_vf, POLY_VALUE_LIKELY);
1875 HOST_WIDE_INT this_likely_vf
1876 = estimated_poly_value (this_vf, POLY_VALUE_LIKELY);
1877
1878 /* If the epilogue is using partial vectors we account for the
1879 partial iteration here too. */
1880 other_factor = niters / other_likely_vf;
1881 if (LOOP_VINFO_USING_PARTIAL_VECTORS_P (other_loop_vinfo)
1882 && niters % other_likely_vf != 0)
1883 other_factor++;
1884
1885 this_factor = niters / this_likely_vf;
1886 if (LOOP_VINFO_USING_PARTIAL_VECTORS_P (this_loop_vinfo)
1887 && niters % this_likely_vf != 0)
1888 this_factor++;
1889 }
1890 else
1891 {
1892 unsigned HOST_WIDE_INT main_vf_max
1893 = estimated_poly_value (main_poly_vf, POLY_VALUE_MAX);
1894 unsigned HOST_WIDE_INT other_vf_max
1895 = estimated_poly_value (other_vf, POLY_VALUE_MAX);
1896 unsigned HOST_WIDE_INT this_vf_max
1897 = estimated_poly_value (this_vf, POLY_VALUE_MAX);
1898
1899 other_factor = CEIL (main_vf_max, other_vf_max);
1900 this_factor = CEIL (main_vf_max, this_vf_max);
1901
1902 /* If the loop is not using partial vectors then it will iterate one
1903 time less than one that does. It is safe to subtract one here,
1904 because the main loop's vf is always at least 2x bigger than that
1905 of an epilogue. */
1906 if (!LOOP_VINFO_USING_PARTIAL_VECTORS_P (other_loop_vinfo))
1907 other_factor -= 1;
1908 if (!LOOP_VINFO_USING_PARTIAL_VECTORS_P (this_loop_vinfo))
1909 this_factor -= 1;
1910 }
1911
1912 /* Compute the costs by multiplying the inside costs with the factor and
1913 add the outside costs for a more complete picture. The factor is the
1914 amount of times we are expecting to iterate this epilogue. */
1915 other_cost = other->body_cost () * other_factor;
1916 this_cost = this->body_cost () * this_factor;
1917 other_cost += other->outside_cost ();
1918 this_cost += this->outside_cost ();
1919 return this_cost < other_cost;
1920 }
1921
1922 /* A <=>-style subroutine of better_main_loop_than_p. Check whether we can
1923 determine the return value of better_main_loop_than_p by comparing the
1924 inside (loop body) costs of THIS and OTHER. Return:
1925
1926 * -1 if better_main_loop_than_p should return true.
1927 * 1 if better_main_loop_than_p should return false.
1928 * 0 if we can't decide. */
1929
1930 int
compare_inside_loop_cost(const vector_costs * other) const1931 vector_costs::compare_inside_loop_cost (const vector_costs *other) const
1932 {
1933 loop_vec_info this_loop_vinfo = as_a<loop_vec_info> (this->m_vinfo);
1934 loop_vec_info other_loop_vinfo = as_a<loop_vec_info> (other->m_vinfo);
1935
1936 struct loop *loop = LOOP_VINFO_LOOP (this_loop_vinfo);
1937 gcc_assert (LOOP_VINFO_LOOP (other_loop_vinfo) == loop);
1938
1939 poly_int64 this_vf = LOOP_VINFO_VECT_FACTOR (this_loop_vinfo);
1940 poly_int64 other_vf = LOOP_VINFO_VECT_FACTOR (other_loop_vinfo);
1941
1942 /* Limit the VFs to what is likely to be the maximum number of iterations,
1943 to handle cases in which at least one loop_vinfo is fully-masked. */
1944 HOST_WIDE_INT estimated_max_niter = likely_max_stmt_executions_int (loop);
1945 if (estimated_max_niter != -1)
1946 {
1947 if (known_le (estimated_max_niter, this_vf))
1948 this_vf = estimated_max_niter;
1949 if (known_le (estimated_max_niter, other_vf))
1950 other_vf = estimated_max_niter;
1951 }
1952
1953 /* Check whether the (fractional) cost per scalar iteration is lower or
1954 higher: this_inside_cost / this_vf vs. other_inside_cost / other_vf. */
1955 poly_int64 rel_this = this_loop_vinfo->vector_costs->body_cost () * other_vf;
1956 poly_int64 rel_other
1957 = other_loop_vinfo->vector_costs->body_cost () * this_vf;
1958
1959 HOST_WIDE_INT est_rel_this_min
1960 = estimated_poly_value (rel_this, POLY_VALUE_MIN);
1961 HOST_WIDE_INT est_rel_this_max
1962 = estimated_poly_value (rel_this, POLY_VALUE_MAX);
1963
1964 HOST_WIDE_INT est_rel_other_min
1965 = estimated_poly_value (rel_other, POLY_VALUE_MIN);
1966 HOST_WIDE_INT est_rel_other_max
1967 = estimated_poly_value (rel_other, POLY_VALUE_MAX);
1968
1969 /* Check first if we can make out an unambigous total order from the minimum
1970 and maximum estimates. */
1971 if (est_rel_this_min < est_rel_other_min
1972 && est_rel_this_max < est_rel_other_max)
1973 return -1;
1974
1975 if (est_rel_other_min < est_rel_this_min
1976 && est_rel_other_max < est_rel_this_max)
1977 return 1;
1978
1979 /* When other_loop_vinfo uses a variable vectorization factor,
1980 we know that it has a lower cost for at least one runtime VF.
1981 However, we don't know how likely that VF is.
1982
1983 One option would be to compare the costs for the estimated VFs.
1984 The problem is that that can put too much pressure on the cost
1985 model. E.g. if the estimated VF is also the lowest possible VF,
1986 and if other_loop_vinfo is 1 unit worse than this_loop_vinfo
1987 for the estimated VF, we'd then choose this_loop_vinfo even
1988 though (a) this_loop_vinfo might not actually be better than
1989 other_loop_vinfo for that VF and (b) it would be significantly
1990 worse at larger VFs.
1991
1992 Here we go for a hacky compromise: pick this_loop_vinfo if it is
1993 no more expensive than other_loop_vinfo even after doubling the
1994 estimated other_loop_vinfo VF. For all but trivial loops, this
1995 ensures that we only pick this_loop_vinfo if it is significantly
1996 better than other_loop_vinfo at the estimated VF. */
1997 if (est_rel_other_min != est_rel_this_min
1998 || est_rel_other_max != est_rel_this_max)
1999 {
2000 HOST_WIDE_INT est_rel_this_likely
2001 = estimated_poly_value (rel_this, POLY_VALUE_LIKELY);
2002 HOST_WIDE_INT est_rel_other_likely
2003 = estimated_poly_value (rel_other, POLY_VALUE_LIKELY);
2004
2005 return est_rel_this_likely * 2 <= est_rel_other_likely ? -1 : 1;
2006 }
2007
2008 return 0;
2009 }
2010
2011 /* A <=>-style subroutine of better_main_loop_than_p, used when there is
2012 nothing to choose between the inside (loop body) costs of THIS and OTHER.
2013 Check whether we can determine the return value of better_main_loop_than_p
2014 by comparing the outside (prologue and epilogue) costs of THIS and OTHER.
2015 Return:
2016
2017 * -1 if better_main_loop_than_p should return true.
2018 * 1 if better_main_loop_than_p should return false.
2019 * 0 if we can't decide. */
2020
2021 int
compare_outside_loop_cost(const vector_costs * other) const2022 vector_costs::compare_outside_loop_cost (const vector_costs *other) const
2023 {
2024 auto this_outside_cost = this->outside_cost ();
2025 auto other_outside_cost = other->outside_cost ();
2026 if (this_outside_cost != other_outside_cost)
2027 return this_outside_cost < other_outside_cost ? -1 : 1;
2028
2029 return 0;
2030 }
2031