]>
Commit | Line | Data |
---|---|---|
48e1416a | 1 | /* Vectorizer Specific Loop Manipulations |
711789cc | 2 | Copyright (C) 2003-2013 Free Software Foundation, Inc. |
48e1416a | 3 | Contributed by Dorit Naishlos <dorit@il.ibm.com> |
fb85abff | 4 | and Ira Rosen <irar@il.ibm.com> |
5 | ||
6 | This file is part of GCC. | |
7 | ||
8 | GCC is free software; you can redistribute it and/or modify it under | |
9 | the terms of the GNU General Public License as published by the Free | |
10 | Software Foundation; either version 3, or (at your option) any later | |
11 | version. | |
12 | ||
13 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
14 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
15 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
16 | for more details. | |
17 | ||
18 | You should have received a copy of the GNU General Public License | |
19 | along with GCC; see the file COPYING3. If not see | |
20 | <http://www.gnu.org/licenses/>. */ | |
21 | ||
22 | #include "config.h" | |
23 | #include "system.h" | |
24 | #include "coretypes.h" | |
7bd765d4 | 25 | #include "dumpfile.h" |
fb85abff | 26 | #include "tm.h" |
fb85abff | 27 | #include "tree.h" |
28 | #include "basic-block.h" | |
ce084dfc | 29 | #include "gimple-pretty-print.h" |
bc61cadb | 30 | #include "tree-ssa-alias.h" |
31 | #include "internal-fn.h" | |
32 | #include "gimple-expr.h" | |
33 | #include "is-a.h" | |
e795d6e1 | 34 | #include "gimple.h" |
a8783bee | 35 | #include "gimplify.h" |
dcf1a1ec | 36 | #include "gimple-iterator.h" |
e795d6e1 | 37 | #include "gimplify-me.h" |
073c1fd5 | 38 | #include "gimple-ssa.h" |
39 | #include "tree-cfg.h" | |
40 | #include "tree-phinodes.h" | |
41 | #include "ssa-iterators.h" | |
9ed99284 | 42 | #include "stringpool.h" |
073c1fd5 | 43 | #include "tree-ssanames.h" |
05d9c18a | 44 | #include "tree-ssa-loop-manip.h" |
073c1fd5 | 45 | #include "tree-into-ssa.h" |
69ee5dbb | 46 | #include "tree-ssa.h" |
b9ed1410 | 47 | #include "tree-pass.h" |
fb85abff | 48 | #include "cfgloop.h" |
0b205f4c | 49 | #include "diagnostic-core.h" |
fb85abff | 50 | #include "tree-scalar-evolution.h" |
51 | #include "tree-vectorizer.h" | |
52 | #include "langhooks.h" | |
53 | ||
54 | /************************************************************************* | |
55 | Simple Loop Peeling Utilities | |
56 | ||
57 | Utilities to support loop peeling for vectorization purposes. | |
58 | *************************************************************************/ | |
59 | ||
60 | ||
61 | /* Renames the use *OP_P. */ | |
62 | ||
63 | static void | |
64 | rename_use_op (use_operand_p op_p) | |
65 | { | |
66 | tree new_name; | |
67 | ||
68 | if (TREE_CODE (USE_FROM_PTR (op_p)) != SSA_NAME) | |
69 | return; | |
70 | ||
71 | new_name = get_current_def (USE_FROM_PTR (op_p)); | |
72 | ||
73 | /* Something defined outside of the loop. */ | |
74 | if (!new_name) | |
75 | return; | |
76 | ||
77 | /* An ordinary ssa name defined in the loop. */ | |
78 | ||
79 | SET_USE (op_p, new_name); | |
80 | } | |
81 | ||
82 | ||
83 | /* Renames the variables in basic block BB. */ | |
84 | ||
c9b2c569 | 85 | static void |
fb85abff | 86 | rename_variables_in_bb (basic_block bb) |
87 | { | |
88 | gimple_stmt_iterator gsi; | |
89 | gimple stmt; | |
90 | use_operand_p use_p; | |
91 | ssa_op_iter iter; | |
92 | edge e; | |
93 | edge_iterator ei; | |
94 | struct loop *loop = bb->loop_father; | |
95 | ||
96 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
97 | { | |
98 | stmt = gsi_stmt (gsi); | |
99 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_ALL_USES) | |
100 | rename_use_op (use_p); | |
101 | } | |
102 | ||
c9b2c569 | 103 | FOR_EACH_EDGE (e, ei, bb->preds) |
fb85abff | 104 | { |
c9b2c569 | 105 | if (!flow_bb_inside_loop_p (loop, e->src)) |
fb85abff | 106 | continue; |
c9b2c569 | 107 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
fb85abff | 108 | rename_use_op (PHI_ARG_DEF_PTR_FROM_EDGE (gsi_stmt (gsi), e)); |
109 | } | |
110 | } | |
111 | ||
112 | ||
b123eaab | 113 | typedef struct |
114 | { | |
115 | tree from, to; | |
116 | basic_block bb; | |
117 | } adjust_info; | |
118 | ||
b123eaab | 119 | /* A stack of values to be adjusted in debug stmts. We have to |
120 | process them LIFO, so that the closest substitution applies. If we | |
121 | processed them FIFO, without the stack, we might substitute uses | |
122 | with a PHI DEF that would soon become non-dominant, and when we got | |
123 | to the suitable one, it wouldn't have anything to substitute any | |
124 | more. */ | |
d70aebca | 125 | static vec<adjust_info, va_heap> adjust_vec; |
b123eaab | 126 | |
127 | /* Adjust any debug stmts that referenced AI->from values to use the | |
128 | loop-closed AI->to, if the references are dominated by AI->bb and | |
129 | not by the definition of AI->from. */ | |
130 | ||
131 | static void | |
132 | adjust_debug_stmts_now (adjust_info *ai) | |
133 | { | |
134 | basic_block bbphi = ai->bb; | |
135 | tree orig_def = ai->from; | |
136 | tree new_def = ai->to; | |
137 | imm_use_iterator imm_iter; | |
138 | gimple stmt; | |
139 | basic_block bbdef = gimple_bb (SSA_NAME_DEF_STMT (orig_def)); | |
140 | ||
141 | gcc_assert (dom_info_available_p (CDI_DOMINATORS)); | |
142 | ||
143 | /* Adjust any debug stmts that held onto non-loop-closed | |
144 | references. */ | |
145 | FOR_EACH_IMM_USE_STMT (stmt, imm_iter, orig_def) | |
146 | { | |
147 | use_operand_p use_p; | |
148 | basic_block bbuse; | |
149 | ||
150 | if (!is_gimple_debug (stmt)) | |
151 | continue; | |
152 | ||
153 | gcc_assert (gimple_debug_bind_p (stmt)); | |
154 | ||
155 | bbuse = gimple_bb (stmt); | |
156 | ||
157 | if ((bbuse == bbphi | |
158 | || dominated_by_p (CDI_DOMINATORS, bbuse, bbphi)) | |
159 | && !(bbuse == bbdef | |
160 | || dominated_by_p (CDI_DOMINATORS, bbuse, bbdef))) | |
161 | { | |
162 | if (new_def) | |
163 | FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter) | |
164 | SET_USE (use_p, new_def); | |
165 | else | |
166 | { | |
167 | gimple_debug_bind_reset_value (stmt); | |
168 | update_stmt (stmt); | |
169 | } | |
170 | } | |
171 | } | |
172 | } | |
173 | ||
174 | /* Adjust debug stmts as scheduled before. */ | |
175 | ||
176 | static void | |
177 | adjust_vec_debug_stmts (void) | |
178 | { | |
179 | if (!MAY_HAVE_DEBUG_STMTS) | |
180 | return; | |
181 | ||
f1f41a6c | 182 | gcc_assert (adjust_vec.exists ()); |
b123eaab | 183 | |
f1f41a6c | 184 | while (!adjust_vec.is_empty ()) |
b123eaab | 185 | { |
f1f41a6c | 186 | adjust_debug_stmts_now (&adjust_vec.last ()); |
187 | adjust_vec.pop (); | |
b123eaab | 188 | } |
189 | ||
f1f41a6c | 190 | adjust_vec.release (); |
b123eaab | 191 | } |
192 | ||
193 | /* Adjust any debug stmts that referenced FROM values to use the | |
194 | loop-closed TO, if the references are dominated by BB and not by | |
195 | the definition of FROM. If adjust_vec is non-NULL, adjustments | |
196 | will be postponed until adjust_vec_debug_stmts is called. */ | |
197 | ||
198 | static void | |
199 | adjust_debug_stmts (tree from, tree to, basic_block bb) | |
200 | { | |
201 | adjust_info ai; | |
202 | ||
0087edc6 | 203 | if (MAY_HAVE_DEBUG_STMTS |
204 | && TREE_CODE (from) == SSA_NAME | |
2510e5cd | 205 | && ! SSA_NAME_IS_DEFAULT_DEF (from) |
0087edc6 | 206 | && ! virtual_operand_p (from)) |
b123eaab | 207 | { |
208 | ai.from = from; | |
209 | ai.to = to; | |
210 | ai.bb = bb; | |
211 | ||
f1f41a6c | 212 | if (adjust_vec.exists ()) |
213 | adjust_vec.safe_push (ai); | |
b123eaab | 214 | else |
215 | adjust_debug_stmts_now (&ai); | |
216 | } | |
217 | } | |
218 | ||
219 | /* Change E's phi arg in UPDATE_PHI to NEW_DEF, and record information | |
220 | to adjust any debug stmts that referenced the old phi arg, | |
221 | presumably non-loop-closed references left over from other | |
222 | transformations. */ | |
223 | ||
224 | static void | |
225 | adjust_phi_and_debug_stmts (gimple update_phi, edge e, tree new_def) | |
226 | { | |
227 | tree orig_def = PHI_ARG_DEF_FROM_EDGE (update_phi, e); | |
228 | ||
229 | SET_PHI_ARG_DEF (update_phi, e->dest_idx, new_def); | |
230 | ||
231 | if (MAY_HAVE_DEBUG_STMTS) | |
232 | adjust_debug_stmts (orig_def, PHI_RESULT (update_phi), | |
233 | gimple_bb (update_phi)); | |
234 | } | |
235 | ||
fb85abff | 236 | |
fb85abff | 237 | /* Update PHI nodes for a guard of the LOOP. |
238 | ||
239 | Input: | |
240 | - LOOP, GUARD_EDGE: LOOP is a loop for which we added guard code that | |
241 | controls whether LOOP is to be executed. GUARD_EDGE is the edge that | |
242 | originates from the guard-bb, skips LOOP and reaches the (unique) exit | |
243 | bb of LOOP. This loop-exit-bb is an empty bb with one successor. | |
244 | We denote this bb NEW_MERGE_BB because before the guard code was added | |
245 | it had a single predecessor (the LOOP header), and now it became a merge | |
246 | point of two paths - the path that ends with the LOOP exit-edge, and | |
247 | the path that ends with GUARD_EDGE. | |
248 | - NEW_EXIT_BB: New basic block that is added by this function between LOOP | |
249 | and NEW_MERGE_BB. It is used to place loop-closed-ssa-form exit-phis. | |
250 | ||
251 | ===> The CFG before the guard-code was added: | |
252 | LOOP_header_bb: | |
253 | loop_body | |
254 | if (exit_loop) goto update_bb | |
255 | else goto LOOP_header_bb | |
256 | update_bb: | |
257 | ||
258 | ==> The CFG after the guard-code was added: | |
259 | guard_bb: | |
260 | if (LOOP_guard_condition) goto new_merge_bb | |
261 | else goto LOOP_header_bb | |
262 | LOOP_header_bb: | |
263 | loop_body | |
264 | if (exit_loop_condition) goto new_merge_bb | |
265 | else goto LOOP_header_bb | |
266 | new_merge_bb: | |
267 | goto update_bb | |
268 | update_bb: | |
269 | ||
270 | ==> The CFG after this function: | |
271 | guard_bb: | |
272 | if (LOOP_guard_condition) goto new_merge_bb | |
273 | else goto LOOP_header_bb | |
274 | LOOP_header_bb: | |
275 | loop_body | |
276 | if (exit_loop_condition) goto new_exit_bb | |
277 | else goto LOOP_header_bb | |
278 | new_exit_bb: | |
279 | new_merge_bb: | |
280 | goto update_bb | |
281 | update_bb: | |
282 | ||
283 | This function: | |
284 | 1. creates and updates the relevant phi nodes to account for the new | |
285 | incoming edge (GUARD_EDGE) into NEW_MERGE_BB. This involves: | |
286 | 1.1. Create phi nodes at NEW_MERGE_BB. | |
287 | 1.2. Update the phi nodes at the successor of NEW_MERGE_BB (denoted | |
288 | UPDATE_BB). UPDATE_BB was the exit-bb of LOOP before NEW_MERGE_BB | |
289 | 2. preserves loop-closed-ssa-form by creating the required phi nodes | |
290 | at the exit of LOOP (i.e, in NEW_EXIT_BB). | |
291 | ||
292 | There are two flavors to this function: | |
293 | ||
294 | slpeel_update_phi_nodes_for_guard1: | |
295 | Here the guard controls whether we enter or skip LOOP, where LOOP is a | |
296 | prolog_loop (loop1 below), and the new phis created in NEW_MERGE_BB are | |
297 | for variables that have phis in the loop header. | |
298 | ||
299 | slpeel_update_phi_nodes_for_guard2: | |
300 | Here the guard controls whether we enter or skip LOOP, where LOOP is an | |
301 | epilog_loop (loop2 below), and the new phis created in NEW_MERGE_BB are | |
302 | for variables that have phis in the loop exit. | |
303 | ||
304 | I.E., the overall structure is: | |
305 | ||
306 | loop1_preheader_bb: | |
307 | guard1 (goto loop1/merge1_bb) | |
308 | loop1 | |
309 | loop1_exit_bb: | |
310 | guard2 (goto merge1_bb/merge2_bb) | |
311 | merge1_bb | |
312 | loop2 | |
313 | loop2_exit_bb | |
314 | merge2_bb | |
315 | next_bb | |
316 | ||
317 | slpeel_update_phi_nodes_for_guard1 takes care of creating phis in | |
318 | loop1_exit_bb and merge1_bb. These are entry phis (phis for the vars | |
319 | that have phis in loop1->header). | |
320 | ||
321 | slpeel_update_phi_nodes_for_guard2 takes care of creating phis in | |
322 | loop2_exit_bb and merge2_bb. These are exit phis (phis for the vars | |
323 | that have phis in next_bb). It also adds some of these phis to | |
324 | loop1_exit_bb. | |
325 | ||
326 | slpeel_update_phi_nodes_for_guard1 is always called before | |
327 | slpeel_update_phi_nodes_for_guard2. They are both needed in order | |
328 | to create correct data-flow and loop-closed-ssa-form. | |
329 | ||
330 | Generally slpeel_update_phi_nodes_for_guard1 creates phis for variables | |
331 | that change between iterations of a loop (and therefore have a phi-node | |
332 | at the loop entry), whereas slpeel_update_phi_nodes_for_guard2 creates | |
48e1416a | 333 | phis for variables that are used out of the loop (and therefore have |
334 | loop-closed exit phis). Some variables may be both updated between | |
fb85abff | 335 | iterations and used after the loop. This is why in loop1_exit_bb we |
336 | may need both entry_phis (created by slpeel_update_phi_nodes_for_guard1) | |
337 | and exit phis (created by slpeel_update_phi_nodes_for_guard2). | |
338 | ||
339 | - IS_NEW_LOOP: if IS_NEW_LOOP is true, then LOOP is a newly created copy of | |
340 | an original loop. i.e., we have: | |
341 | ||
342 | orig_loop | |
343 | guard_bb (goto LOOP/new_merge) | |
344 | new_loop <-- LOOP | |
345 | new_exit | |
346 | new_merge | |
347 | next_bb | |
348 | ||
349 | If IS_NEW_LOOP is false, then LOOP is an original loop, in which case we | |
350 | have: | |
351 | ||
352 | new_loop | |
353 | guard_bb (goto LOOP/new_merge) | |
354 | orig_loop <-- LOOP | |
355 | new_exit | |
356 | new_merge | |
357 | next_bb | |
358 | ||
359 | The SSA names defined in the original loop have a current | |
360 | reaching definition that that records the corresponding new | |
361 | ssa-name used in the new duplicated loop copy. | |
362 | */ | |
363 | ||
364 | /* Function slpeel_update_phi_nodes_for_guard1 | |
48e1416a | 365 | |
fb85abff | 366 | Input: |
367 | - GUARD_EDGE, LOOP, IS_NEW_LOOP, NEW_EXIT_BB - as explained above. | |
368 | - DEFS - a bitmap of ssa names to mark new names for which we recorded | |
48e1416a | 369 | information. |
370 | ||
fb85abff | 371 | In the context of the overall structure, we have: |
372 | ||
48e1416a | 373 | loop1_preheader_bb: |
fb85abff | 374 | guard1 (goto loop1/merge1_bb) |
375 | LOOP-> loop1 | |
376 | loop1_exit_bb: | |
377 | guard2 (goto merge1_bb/merge2_bb) | |
378 | merge1_bb | |
379 | loop2 | |
380 | loop2_exit_bb | |
381 | merge2_bb | |
382 | next_bb | |
383 | ||
384 | For each name updated between loop iterations (i.e - for each name that has | |
385 | an entry (loop-header) phi in LOOP) we create a new phi in: | |
386 | 1. merge1_bb (to account for the edge from guard1) | |
387 | 2. loop1_exit_bb (an exit-phi to keep LOOP in loop-closed form) | |
388 | */ | |
389 | ||
390 | static void | |
391 | slpeel_update_phi_nodes_for_guard1 (edge guard_edge, struct loop *loop, | |
1e8cf080 | 392 | bool is_new_loop, basic_block *new_exit_bb) |
fb85abff | 393 | { |
394 | gimple orig_phi, new_phi; | |
395 | gimple update_phi, update_phi2; | |
396 | tree guard_arg, loop_arg; | |
397 | basic_block new_merge_bb = guard_edge->dest; | |
398 | edge e = EDGE_SUCC (new_merge_bb, 0); | |
399 | basic_block update_bb = e->dest; | |
400 | basic_block orig_bb = loop->header; | |
401 | edge new_exit_e; | |
402 | tree current_new_name; | |
fb85abff | 403 | gimple_stmt_iterator gsi_orig, gsi_update; |
404 | ||
405 | /* Create new bb between loop and new_merge_bb. */ | |
406 | *new_exit_bb = split_edge (single_exit (loop)); | |
407 | ||
408 | new_exit_e = EDGE_SUCC (*new_exit_bb, 0); | |
409 | ||
410 | for (gsi_orig = gsi_start_phis (orig_bb), | |
411 | gsi_update = gsi_start_phis (update_bb); | |
412 | !gsi_end_p (gsi_orig) && !gsi_end_p (gsi_update); | |
413 | gsi_next (&gsi_orig), gsi_next (&gsi_update)) | |
414 | { | |
38091110 | 415 | source_location loop_locus, guard_locus; |
874117c8 | 416 | tree new_res; |
fb85abff | 417 | orig_phi = gsi_stmt (gsi_orig); |
418 | update_phi = gsi_stmt (gsi_update); | |
419 | ||
fb85abff | 420 | /** 1. Handle new-merge-point phis **/ |
421 | ||
422 | /* 1.1. Generate new phi node in NEW_MERGE_BB: */ | |
874117c8 | 423 | new_res = copy_ssa_name (PHI_RESULT (orig_phi), NULL); |
424 | new_phi = create_phi_node (new_res, new_merge_bb); | |
fb85abff | 425 | |
426 | /* 1.2. NEW_MERGE_BB has two incoming edges: GUARD_EDGE and the exit-edge | |
427 | of LOOP. Set the two phi args in NEW_PHI for these edges: */ | |
428 | loop_arg = PHI_ARG_DEF_FROM_EDGE (orig_phi, EDGE_SUCC (loop->latch, 0)); | |
48e1416a | 429 | loop_locus = gimple_phi_arg_location_from_edge (orig_phi, |
430 | EDGE_SUCC (loop->latch, | |
efbcb6de | 431 | 0)); |
fb85abff | 432 | guard_arg = PHI_ARG_DEF_FROM_EDGE (orig_phi, loop_preheader_edge (loop)); |
48e1416a | 433 | guard_locus |
434 | = gimple_phi_arg_location_from_edge (orig_phi, | |
efbcb6de | 435 | loop_preheader_edge (loop)); |
fb85abff | 436 | |
60d535d2 | 437 | add_phi_arg (new_phi, loop_arg, new_exit_e, loop_locus); |
438 | add_phi_arg (new_phi, guard_arg, guard_edge, guard_locus); | |
fb85abff | 439 | |
440 | /* 1.3. Update phi in successor block. */ | |
441 | gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi, e) == loop_arg | |
442 | || PHI_ARG_DEF_FROM_EDGE (update_phi, e) == guard_arg); | |
b123eaab | 443 | adjust_phi_and_debug_stmts (update_phi, e, PHI_RESULT (new_phi)); |
fb85abff | 444 | update_phi2 = new_phi; |
445 | ||
446 | ||
447 | /** 2. Handle loop-closed-ssa-form phis **/ | |
448 | ||
7c782c9b | 449 | if (virtual_operand_p (PHI_RESULT (orig_phi))) |
fb85abff | 450 | continue; |
451 | ||
452 | /* 2.1. Generate new phi node in NEW_EXIT_BB: */ | |
874117c8 | 453 | new_res = copy_ssa_name (PHI_RESULT (orig_phi), NULL); |
454 | new_phi = create_phi_node (new_res, *new_exit_bb); | |
fb85abff | 455 | |
456 | /* 2.2. NEW_EXIT_BB has one incoming edge: the exit-edge of the loop. */ | |
60d535d2 | 457 | add_phi_arg (new_phi, loop_arg, single_exit (loop), loop_locus); |
fb85abff | 458 | |
459 | /* 2.3. Update phi in successor of NEW_EXIT_BB: */ | |
460 | gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi2, new_exit_e) == loop_arg); | |
b123eaab | 461 | adjust_phi_and_debug_stmts (update_phi2, new_exit_e, |
462 | PHI_RESULT (new_phi)); | |
fb85abff | 463 | |
464 | /* 2.4. Record the newly created name with set_current_def. | |
465 | We want to find a name such that | |
466 | name = get_current_def (orig_loop_name) | |
467 | and to set its current definition as follows: | |
468 | set_current_def (name, new_phi_name) | |
469 | ||
470 | If LOOP is a new loop then loop_arg is already the name we're | |
471 | looking for. If LOOP is the original loop, then loop_arg is | |
472 | the orig_loop_name and the relevant name is recorded in its | |
473 | current reaching definition. */ | |
474 | if (is_new_loop) | |
475 | current_new_name = loop_arg; | |
476 | else | |
477 | { | |
478 | current_new_name = get_current_def (loop_arg); | |
479 | /* current_def is not available only if the variable does not | |
480 | change inside the loop, in which case we also don't care | |
481 | about recording a current_def for it because we won't be | |
482 | trying to create loop-exit-phis for it. */ | |
483 | if (!current_new_name) | |
484 | continue; | |
485 | } | |
486 | gcc_assert (get_current_def (current_new_name) == NULL_TREE); | |
487 | ||
488 | set_current_def (current_new_name, PHI_RESULT (new_phi)); | |
fb85abff | 489 | } |
490 | } | |
491 | ||
492 | ||
493 | /* Function slpeel_update_phi_nodes_for_guard2 | |
494 | ||
495 | Input: | |
496 | - GUARD_EDGE, LOOP, IS_NEW_LOOP, NEW_EXIT_BB - as explained above. | |
497 | ||
498 | In the context of the overall structure, we have: | |
499 | ||
48e1416a | 500 | loop1_preheader_bb: |
fb85abff | 501 | guard1 (goto loop1/merge1_bb) |
502 | loop1 | |
48e1416a | 503 | loop1_exit_bb: |
fb85abff | 504 | guard2 (goto merge1_bb/merge2_bb) |
505 | merge1_bb | |
506 | LOOP-> loop2 | |
507 | loop2_exit_bb | |
508 | merge2_bb | |
509 | next_bb | |
510 | ||
511 | For each name used out side the loop (i.e - for each name that has an exit | |
512 | phi in next_bb) we create a new phi in: | |
48e1416a | 513 | 1. merge2_bb (to account for the edge from guard_bb) |
fb85abff | 514 | 2. loop2_exit_bb (an exit-phi to keep LOOP in loop-closed form) |
515 | 3. guard2 bb (an exit phi to keep the preceding loop in loop-closed form), | |
516 | if needed (if it wasn't handled by slpeel_update_phis_nodes_for_phi1). | |
517 | */ | |
518 | ||
519 | static void | |
520 | slpeel_update_phi_nodes_for_guard2 (edge guard_edge, struct loop *loop, | |
521 | bool is_new_loop, basic_block *new_exit_bb) | |
522 | { | |
523 | gimple orig_phi, new_phi; | |
524 | gimple update_phi, update_phi2; | |
525 | tree guard_arg, loop_arg; | |
526 | basic_block new_merge_bb = guard_edge->dest; | |
527 | edge e = EDGE_SUCC (new_merge_bb, 0); | |
528 | basic_block update_bb = e->dest; | |
529 | edge new_exit_e; | |
530 | tree orig_def, orig_def_new_name; | |
531 | tree new_name, new_name2; | |
532 | tree arg; | |
533 | gimple_stmt_iterator gsi; | |
534 | ||
535 | /* Create new bb between loop and new_merge_bb. */ | |
536 | *new_exit_bb = split_edge (single_exit (loop)); | |
537 | ||
538 | new_exit_e = EDGE_SUCC (*new_exit_bb, 0); | |
539 | ||
540 | for (gsi = gsi_start_phis (update_bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
541 | { | |
874117c8 | 542 | tree new_res; |
fb85abff | 543 | update_phi = gsi_stmt (gsi); |
544 | orig_phi = update_phi; | |
545 | orig_def = PHI_ARG_DEF_FROM_EDGE (orig_phi, e); | |
546 | /* This loop-closed-phi actually doesn't represent a use | |
48e1416a | 547 | out of the loop - the phi arg is a constant. */ |
fb85abff | 548 | if (TREE_CODE (orig_def) != SSA_NAME) |
549 | continue; | |
550 | orig_def_new_name = get_current_def (orig_def); | |
551 | arg = NULL_TREE; | |
552 | ||
553 | /** 1. Handle new-merge-point phis **/ | |
554 | ||
555 | /* 1.1. Generate new phi node in NEW_MERGE_BB: */ | |
874117c8 | 556 | new_res = copy_ssa_name (PHI_RESULT (orig_phi), NULL); |
557 | new_phi = create_phi_node (new_res, new_merge_bb); | |
fb85abff | 558 | |
559 | /* 1.2. NEW_MERGE_BB has two incoming edges: GUARD_EDGE and the exit-edge | |
560 | of LOOP. Set the two PHI args in NEW_PHI for these edges: */ | |
561 | new_name = orig_def; | |
562 | new_name2 = NULL_TREE; | |
563 | if (orig_def_new_name) | |
564 | { | |
565 | new_name = orig_def_new_name; | |
566 | /* Some variables have both loop-entry-phis and loop-exit-phis. | |
567 | Such variables were given yet newer names by phis placed in | |
568 | guard_bb by slpeel_update_phi_nodes_for_guard1. I.e: | |
569 | new_name2 = get_current_def (get_current_def (orig_name)). */ | |
570 | new_name2 = get_current_def (new_name); | |
571 | } | |
48e1416a | 572 | |
fb85abff | 573 | if (is_new_loop) |
574 | { | |
575 | guard_arg = orig_def; | |
576 | loop_arg = new_name; | |
577 | } | |
578 | else | |
579 | { | |
580 | guard_arg = new_name; | |
581 | loop_arg = orig_def; | |
582 | } | |
583 | if (new_name2) | |
584 | guard_arg = new_name2; | |
48e1416a | 585 | |
60d535d2 | 586 | add_phi_arg (new_phi, loop_arg, new_exit_e, UNKNOWN_LOCATION); |
587 | add_phi_arg (new_phi, guard_arg, guard_edge, UNKNOWN_LOCATION); | |
fb85abff | 588 | |
589 | /* 1.3. Update phi in successor block. */ | |
590 | gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi, e) == orig_def); | |
b123eaab | 591 | adjust_phi_and_debug_stmts (update_phi, e, PHI_RESULT (new_phi)); |
fb85abff | 592 | update_phi2 = new_phi; |
593 | ||
594 | ||
595 | /** 2. Handle loop-closed-ssa-form phis **/ | |
596 | ||
597 | /* 2.1. Generate new phi node in NEW_EXIT_BB: */ | |
874117c8 | 598 | new_res = copy_ssa_name (PHI_RESULT (orig_phi), NULL); |
599 | new_phi = create_phi_node (new_res, *new_exit_bb); | |
fb85abff | 600 | |
601 | /* 2.2. NEW_EXIT_BB has one incoming edge: the exit-edge of the loop. */ | |
60d535d2 | 602 | add_phi_arg (new_phi, loop_arg, single_exit (loop), UNKNOWN_LOCATION); |
fb85abff | 603 | |
604 | /* 2.3. Update phi in successor of NEW_EXIT_BB: */ | |
605 | gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi2, new_exit_e) == loop_arg); | |
b123eaab | 606 | adjust_phi_and_debug_stmts (update_phi2, new_exit_e, |
607 | PHI_RESULT (new_phi)); | |
fb85abff | 608 | |
609 | ||
610 | /** 3. Handle loop-closed-ssa-form phis for first loop **/ | |
611 | ||
612 | /* 3.1. Find the relevant names that need an exit-phi in | |
613 | GUARD_BB, i.e. names for which | |
614 | slpeel_update_phi_nodes_for_guard1 had not already created a | |
615 | phi node. This is the case for names that are used outside | |
616 | the loop (and therefore need an exit phi) but are not updated | |
617 | across loop iterations (and therefore don't have a | |
618 | loop-header-phi). | |
619 | ||
620 | slpeel_update_phi_nodes_for_guard1 is responsible for | |
621 | creating loop-exit phis in GUARD_BB for names that have a | |
622 | loop-header-phi. When such a phi is created we also record | |
623 | the new name in its current definition. If this new name | |
624 | exists, then guard_arg was set to this new name (see 1.2 | |
625 | above). Therefore, if guard_arg is not this new name, this | |
626 | is an indication that an exit-phi in GUARD_BB was not yet | |
627 | created, so we take care of it here. */ | |
628 | if (guard_arg == new_name2) | |
629 | continue; | |
630 | arg = guard_arg; | |
631 | ||
632 | /* 3.2. Generate new phi node in GUARD_BB: */ | |
874117c8 | 633 | new_res = copy_ssa_name (PHI_RESULT (orig_phi), NULL); |
634 | new_phi = create_phi_node (new_res, guard_edge->src); | |
fb85abff | 635 | |
636 | /* 3.3. GUARD_BB has one incoming edge: */ | |
637 | gcc_assert (EDGE_COUNT (guard_edge->src->preds) == 1); | |
48e1416a | 638 | add_phi_arg (new_phi, arg, EDGE_PRED (guard_edge->src, 0), |
60d535d2 | 639 | UNKNOWN_LOCATION); |
fb85abff | 640 | |
641 | /* 3.4. Update phi in successor of GUARD_BB: */ | |
642 | gcc_assert (PHI_ARG_DEF_FROM_EDGE (update_phi2, guard_edge) | |
643 | == guard_arg); | |
b123eaab | 644 | adjust_phi_and_debug_stmts (update_phi2, guard_edge, |
645 | PHI_RESULT (new_phi)); | |
fb85abff | 646 | } |
647 | } | |
648 | ||
649 | ||
650 | /* Make the LOOP iterate NITERS times. This is done by adding a new IV | |
651 | that starts at zero, increases by one and its limit is NITERS. | |
652 | ||
653 | Assumption: the exit-condition of LOOP is the last stmt in the loop. */ | |
654 | ||
655 | void | |
656 | slpeel_make_loop_iterate_ntimes (struct loop *loop, tree niters) | |
657 | { | |
658 | tree indx_before_incr, indx_after_incr; | |
659 | gimple cond_stmt; | |
660 | gimple orig_cond; | |
661 | edge exit_edge = single_exit (loop); | |
662 | gimple_stmt_iterator loop_cond_gsi; | |
663 | gimple_stmt_iterator incr_gsi; | |
664 | bool insert_after; | |
665 | tree init = build_int_cst (TREE_TYPE (niters), 0); | |
666 | tree step = build_int_cst (TREE_TYPE (niters), 1); | |
36f39b2e | 667 | source_location loop_loc; |
fb85abff | 668 | enum tree_code code; |
669 | ||
670 | orig_cond = get_loop_exit_condition (loop); | |
671 | gcc_assert (orig_cond); | |
672 | loop_cond_gsi = gsi_for_stmt (orig_cond); | |
673 | ||
674 | standard_iv_increment_position (loop, &incr_gsi, &insert_after); | |
675 | create_iv (init, step, NULL_TREE, loop, | |
676 | &incr_gsi, insert_after, &indx_before_incr, &indx_after_incr); | |
677 | ||
678 | indx_after_incr = force_gimple_operand_gsi (&loop_cond_gsi, indx_after_incr, | |
679 | true, NULL_TREE, true, | |
680 | GSI_SAME_STMT); | |
681 | niters = force_gimple_operand_gsi (&loop_cond_gsi, niters, true, NULL_TREE, | |
682 | true, GSI_SAME_STMT); | |
683 | ||
684 | code = (exit_edge->flags & EDGE_TRUE_VALUE) ? GE_EXPR : LT_EXPR; | |
685 | cond_stmt = gimple_build_cond (code, indx_after_incr, niters, NULL_TREE, | |
686 | NULL_TREE); | |
687 | ||
688 | gsi_insert_before (&loop_cond_gsi, cond_stmt, GSI_SAME_STMT); | |
689 | ||
690 | /* Remove old loop exit test: */ | |
691 | gsi_remove (&loop_cond_gsi, true); | |
706567b8 | 692 | free_stmt_vec_info (orig_cond); |
fb85abff | 693 | |
694 | loop_loc = find_loop_location (loop); | |
6d8fb6cf | 695 | if (dump_enabled_p ()) |
fb85abff | 696 | { |
36f39b2e | 697 | if (LOCATION_LOCUS (loop_loc) != UNKNOWN_LOCATION) |
698 | dump_printf (MSG_NOTE, "\nloop at %s:%d: ", LOCATION_FILE (loop_loc), | |
699 | LOCATION_LINE (loop_loc)); | |
7bd765d4 | 700 | dump_gimple_stmt (MSG_NOTE, TDF_SLIM, cond_stmt, 0); |
78bb46f5 | 701 | dump_printf (MSG_NOTE, "\n"); |
fb85abff | 702 | } |
fb85abff | 703 | loop->nb_iterations = niters; |
704 | } | |
705 | ||
706 | ||
48e1416a | 707 | /* Given LOOP this function generates a new copy of it and puts it |
fb85abff | 708 | on E which is either the entry or exit of LOOP. */ |
709 | ||
710 | struct loop * | |
711 | slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *loop, edge e) | |
712 | { | |
713 | struct loop *new_loop; | |
714 | basic_block *new_bbs, *bbs; | |
715 | bool at_exit; | |
716 | bool was_imm_dom; | |
48e1416a | 717 | basic_block exit_dest; |
fb85abff | 718 | edge exit, new_exit; |
fb85abff | 719 | |
c9b2c569 | 720 | exit = single_exit (loop); |
721 | at_exit = (e == exit); | |
fb85abff | 722 | if (!at_exit && e != loop_preheader_edge (loop)) |
723 | return NULL; | |
724 | ||
c9b2c569 | 725 | bbs = XNEWVEC (basic_block, loop->num_nodes + 1); |
726 | get_loop_body_with_size (loop, bbs, loop->num_nodes); | |
fb85abff | 727 | |
728 | /* Check whether duplication is possible. */ | |
729 | if (!can_copy_bbs_p (bbs, loop->num_nodes)) | |
730 | { | |
731 | free (bbs); | |
732 | return NULL; | |
733 | } | |
734 | ||
735 | /* Generate new loop structure. */ | |
736 | new_loop = duplicate_loop (loop, loop_outer (loop)); | |
c9b2c569 | 737 | duplicate_subloops (loop, new_loop); |
fb85abff | 738 | |
c9b2c569 | 739 | exit_dest = exit->dest; |
48e1416a | 740 | was_imm_dom = (get_immediate_dominator (CDI_DOMINATORS, |
741 | exit_dest) == loop->header ? | |
fb85abff | 742 | true : false); |
743 | ||
c9b2c569 | 744 | /* Also copy the pre-header, this avoids jumping through hoops to |
745 | duplicate the loop entry PHI arguments. Create an empty | |
746 | pre-header unconditionally for this. */ | |
747 | basic_block preheader = split_edge (loop_preheader_edge (loop)); | |
748 | edge entry_e = single_pred_edge (preheader); | |
749 | bbs[loop->num_nodes] = preheader; | |
750 | new_bbs = XNEWVEC (basic_block, loop->num_nodes + 1); | |
fb85abff | 751 | |
c9b2c569 | 752 | copy_bbs (bbs, loop->num_nodes + 1, new_bbs, |
fb85abff | 753 | &exit, 1, &new_exit, NULL, |
d99f53b2 | 754 | e->src, true); |
c9b2c569 | 755 | basic_block new_preheader = new_bbs[loop->num_nodes]; |
fb85abff | 756 | |
c9b2c569 | 757 | add_phi_args_after_copy (new_bbs, loop->num_nodes + 1, NULL); |
48e1416a | 758 | |
fb85abff | 759 | if (at_exit) /* Add the loop copy at exit. */ |
760 | { | |
c9b2c569 | 761 | redirect_edge_and_branch_force (e, new_preheader); |
762 | flush_pending_stmts (e); | |
763 | set_immediate_dominator (CDI_DOMINATORS, new_preheader, e->src); | |
fb85abff | 764 | if (was_imm_dom) |
765 | set_immediate_dominator (CDI_DOMINATORS, exit_dest, new_loop->header); | |
c9b2c569 | 766 | |
767 | /* And remove the non-necessary forwarder again. Keep the other | |
768 | one so we have a proper pre-header for the loop at the exit edge. */ | |
769 | redirect_edge_pred (single_succ_edge (preheader), single_pred (preheader)); | |
770 | delete_basic_block (preheader); | |
771 | set_immediate_dominator (CDI_DOMINATORS, loop->header, | |
772 | loop_preheader_edge (loop)->src); | |
fb85abff | 773 | } |
774 | else /* Add the copy at entry. */ | |
775 | { | |
c9b2c569 | 776 | redirect_edge_and_branch_force (entry_e, new_preheader); |
777 | flush_pending_stmts (entry_e); | |
778 | set_immediate_dominator (CDI_DOMINATORS, new_preheader, entry_e->src); | |
779 | ||
780 | redirect_edge_and_branch_force (new_exit, preheader); | |
781 | flush_pending_stmts (new_exit); | |
782 | set_immediate_dominator (CDI_DOMINATORS, preheader, new_exit->src); | |
783 | ||
784 | /* And remove the non-necessary forwarder again. Keep the other | |
785 | one so we have a proper pre-header for the loop at the exit edge. */ | |
786 | redirect_edge_pred (single_succ_edge (new_preheader), single_pred (new_preheader)); | |
787 | delete_basic_block (new_preheader); | |
788 | set_immediate_dominator (CDI_DOMINATORS, new_loop->header, | |
789 | loop_preheader_edge (new_loop)->src); | |
fb85abff | 790 | } |
791 | ||
c9b2c569 | 792 | for (unsigned i = 0; i < loop->num_nodes+1; i++) |
793 | rename_variables_in_bb (new_bbs[i]); | |
794 | ||
fb85abff | 795 | free (new_bbs); |
796 | free (bbs); | |
797 | ||
c9b2c569 | 798 | #ifdef ENABLE_CHECKING |
799 | verify_dominators (CDI_DOMINATORS); | |
800 | #endif | |
801 | ||
fb85abff | 802 | return new_loop; |
803 | } | |
804 | ||
805 | ||
806 | /* Given the condition statement COND, put it as the last statement | |
807 | of GUARD_BB; EXIT_BB is the basic block to skip the loop; | |
48e1416a | 808 | Assumes that this is the single exit of the guarded loop. |
23a3430d | 809 | Returns the skip edge, inserts new stmts on the COND_EXPR_STMT_LIST. */ |
fb85abff | 810 | |
811 | static edge | |
23a3430d | 812 | slpeel_add_loop_guard (basic_block guard_bb, tree cond, |
813 | gimple_seq cond_expr_stmt_list, | |
877584e4 | 814 | basic_block exit_bb, basic_block dom_bb, |
815 | int probability) | |
fb85abff | 816 | { |
817 | gimple_stmt_iterator gsi; | |
818 | edge new_e, enter_e; | |
819 | gimple cond_stmt; | |
820 | gimple_seq gimplify_stmt_list = NULL; | |
821 | ||
822 | enter_e = EDGE_SUCC (guard_bb, 0); | |
823 | enter_e->flags &= ~EDGE_FALLTHRU; | |
824 | enter_e->flags |= EDGE_FALSE_VALUE; | |
825 | gsi = gsi_last_bb (guard_bb); | |
826 | ||
87ae3989 | 827 | cond = force_gimple_operand_1 (cond, &gimplify_stmt_list, is_gimple_condexpr, |
828 | NULL_TREE); | |
23a3430d | 829 | if (gimplify_stmt_list) |
830 | gimple_seq_add_seq (&cond_expr_stmt_list, gimplify_stmt_list); | |
87ae3989 | 831 | cond_stmt = gimple_build_cond_from_tree (cond, NULL_TREE, NULL_TREE); |
23a3430d | 832 | if (cond_expr_stmt_list) |
833 | gsi_insert_seq_after (&gsi, cond_expr_stmt_list, GSI_NEW_STMT); | |
fb85abff | 834 | |
835 | gsi = gsi_last_bb (guard_bb); | |
836 | gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT); | |
837 | ||
838 | /* Add new edge to connect guard block to the merge/loop-exit block. */ | |
839 | new_e = make_edge (guard_bb, exit_bb, EDGE_TRUE_VALUE); | |
877584e4 | 840 | |
841 | new_e->count = guard_bb->count; | |
842 | new_e->probability = probability; | |
843 | new_e->count = apply_probability (enter_e->count, probability); | |
844 | enter_e->count -= new_e->count; | |
845 | enter_e->probability = inverse_probability (probability); | |
fb85abff | 846 | set_immediate_dominator (CDI_DOMINATORS, exit_bb, dom_bb); |
847 | return new_e; | |
848 | } | |
849 | ||
850 | ||
851 | /* This function verifies that the following restrictions apply to LOOP: | |
852 | (1) it is innermost | |
853 | (2) it consists of exactly 2 basic blocks - header, and an empty latch. | |
854 | (3) it is single entry, single exit | |
855 | (4) its exit condition is the last stmt in the header | |
856 | (5) E is the entry/exit edge of LOOP. | |
857 | */ | |
858 | ||
859 | bool | |
860 | slpeel_can_duplicate_loop_p (const struct loop *loop, const_edge e) | |
861 | { | |
862 | edge exit_e = single_exit (loop); | |
863 | edge entry_e = loop_preheader_edge (loop); | |
864 | gimple orig_cond = get_loop_exit_condition (loop); | |
865 | gimple_stmt_iterator loop_exit_gsi = gsi_last_bb (exit_e->src); | |
866 | ||
fb85abff | 867 | if (loop->inner |
868 | /* All loops have an outer scope; the only case loop->outer is NULL is for | |
869 | the function itself. */ | |
870 | || !loop_outer (loop) | |
871 | || loop->num_nodes != 2 | |
872 | || !empty_block_p (loop->latch) | |
873 | || !single_exit (loop) | |
874 | /* Verify that new loop exit condition can be trivially modified. */ | |
875 | || (!orig_cond || orig_cond != gsi_stmt (loop_exit_gsi)) | |
876 | || (e != exit_e && e != entry_e)) | |
877 | return false; | |
878 | ||
879 | return true; | |
880 | } | |
881 | ||
882 | #ifdef ENABLE_CHECKING | |
883 | static void | |
884 | slpeel_verify_cfg_after_peeling (struct loop *first_loop, | |
885 | struct loop *second_loop) | |
886 | { | |
887 | basic_block loop1_exit_bb = single_exit (first_loop)->dest; | |
888 | basic_block loop2_entry_bb = loop_preheader_edge (second_loop)->src; | |
889 | basic_block loop1_entry_bb = loop_preheader_edge (first_loop)->src; | |
890 | ||
891 | /* A guard that controls whether the second_loop is to be executed or skipped | |
892 | is placed in first_loop->exit. first_loop->exit therefore has two | |
893 | successors - one is the preheader of second_loop, and the other is a bb | |
894 | after second_loop. | |
895 | */ | |
896 | gcc_assert (EDGE_COUNT (loop1_exit_bb->succs) == 2); | |
48e1416a | 897 | |
fb85abff | 898 | /* 1. Verify that one of the successors of first_loop->exit is the preheader |
899 | of second_loop. */ | |
48e1416a | 900 | |
fb85abff | 901 | /* The preheader of new_loop is expected to have two predecessors: |
902 | first_loop->exit and the block that precedes first_loop. */ | |
903 | ||
48e1416a | 904 | gcc_assert (EDGE_COUNT (loop2_entry_bb->preds) == 2 |
fb85abff | 905 | && ((EDGE_PRED (loop2_entry_bb, 0)->src == loop1_exit_bb |
906 | && EDGE_PRED (loop2_entry_bb, 1)->src == loop1_entry_bb) | |
907 | || (EDGE_PRED (loop2_entry_bb, 1)->src == loop1_exit_bb | |
908 | && EDGE_PRED (loop2_entry_bb, 0)->src == loop1_entry_bb))); | |
48e1416a | 909 | |
fb85abff | 910 | /* Verify that the other successor of first_loop->exit is after the |
911 | second_loop. */ | |
912 | /* TODO */ | |
913 | } | |
914 | #endif | |
915 | ||
916 | /* If the run time cost model check determines that vectorization is | |
917 | not profitable and hence scalar loop should be generated then set | |
918 | FIRST_NITERS to prologue peeled iterations. This will allow all the | |
919 | iterations to be executed in the prologue peeled scalar loop. */ | |
920 | ||
921 | static void | |
922 | set_prologue_iterations (basic_block bb_before_first_loop, | |
2f630015 | 923 | tree *first_niters, |
fb85abff | 924 | struct loop *loop, |
877584e4 | 925 | unsigned int th, |
926 | int probability) | |
fb85abff | 927 | { |
928 | edge e; | |
929 | basic_block cond_bb, then_bb; | |
930 | tree var, prologue_after_cost_adjust_name; | |
931 | gimple_stmt_iterator gsi; | |
932 | gimple newphi; | |
933 | edge e_true, e_false, e_fallthru; | |
934 | gimple cond_stmt; | |
87ae3989 | 935 | gimple_seq stmts = NULL; |
fb85abff | 936 | tree cost_pre_condition = NULL_TREE; |
48e1416a | 937 | tree scalar_loop_iters = |
fb85abff | 938 | unshare_expr (LOOP_VINFO_NITERS_UNCHANGED (loop_vec_info_for_loop (loop))); |
939 | ||
940 | e = single_pred_edge (bb_before_first_loop); | |
9af5ce0c | 941 | cond_bb = split_edge (e); |
fb85abff | 942 | |
943 | e = single_pred_edge (bb_before_first_loop); | |
9af5ce0c | 944 | then_bb = split_edge (e); |
fb85abff | 945 | set_immediate_dominator (CDI_DOMINATORS, then_bb, cond_bb); |
946 | ||
947 | e_false = make_single_succ_edge (cond_bb, bb_before_first_loop, | |
948 | EDGE_FALSE_VALUE); | |
949 | set_immediate_dominator (CDI_DOMINATORS, bb_before_first_loop, cond_bb); | |
950 | ||
951 | e_true = EDGE_PRED (then_bb, 0); | |
952 | e_true->flags &= ~EDGE_FALLTHRU; | |
953 | e_true->flags |= EDGE_TRUE_VALUE; | |
954 | ||
877584e4 | 955 | e_true->probability = probability; |
956 | e_false->probability = inverse_probability (probability); | |
957 | e_true->count = apply_probability (cond_bb->count, probability); | |
958 | e_false->count = cond_bb->count - e_true->count; | |
959 | then_bb->frequency = EDGE_FREQUENCY (e_true); | |
960 | then_bb->count = e_true->count; | |
961 | ||
fb85abff | 962 | e_fallthru = EDGE_SUCC (then_bb, 0); |
877584e4 | 963 | e_fallthru->count = then_bb->count; |
fb85abff | 964 | |
87ae3989 | 965 | gsi = gsi_last_bb (cond_bb); |
fb85abff | 966 | cost_pre_condition = |
48e1416a | 967 | fold_build2 (LE_EXPR, boolean_type_node, scalar_loop_iters, |
fb85abff | 968 | build_int_cst (TREE_TYPE (scalar_loop_iters), th)); |
969 | cost_pre_condition = | |
87ae3989 | 970 | force_gimple_operand_gsi_1 (&gsi, cost_pre_condition, is_gimple_condexpr, |
971 | NULL_TREE, false, GSI_CONTINUE_LINKING); | |
972 | cond_stmt = gimple_build_cond_from_tree (cost_pre_condition, | |
973 | NULL_TREE, NULL_TREE); | |
fb85abff | 974 | gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT); |
48e1416a | 975 | |
fb85abff | 976 | var = create_tmp_var (TREE_TYPE (scalar_loop_iters), |
977 | "prologue_after_cost_adjust"); | |
48e1416a | 978 | prologue_after_cost_adjust_name = |
fb85abff | 979 | force_gimple_operand (scalar_loop_iters, &stmts, false, var); |
980 | ||
981 | gsi = gsi_last_bb (then_bb); | |
982 | if (stmts) | |
983 | gsi_insert_seq_after (&gsi, stmts, GSI_NEW_STMT); | |
984 | ||
985 | newphi = create_phi_node (var, bb_before_first_loop); | |
48e1416a | 986 | add_phi_arg (newphi, prologue_after_cost_adjust_name, e_fallthru, |
60d535d2 | 987 | UNKNOWN_LOCATION); |
988 | add_phi_arg (newphi, *first_niters, e_false, UNKNOWN_LOCATION); | |
fb85abff | 989 | |
2f630015 | 990 | *first_niters = PHI_RESULT (newphi); |
fb85abff | 991 | } |
992 | ||
fb85abff | 993 | /* Function slpeel_tree_peel_loop_to_edge. |
994 | ||
995 | Peel the first (last) iterations of LOOP into a new prolog (epilog) loop | |
996 | that is placed on the entry (exit) edge E of LOOP. After this transformation | |
997 | we have two loops one after the other - first-loop iterates FIRST_NITERS | |
998 | times, and second-loop iterates the remainder NITERS - FIRST_NITERS times. | |
48e1416a | 999 | If the cost model indicates that it is profitable to emit a scalar |
fb85abff | 1000 | loop instead of the vector one, then the prolog (epilog) loop will iterate |
1001 | for the entire unchanged scalar iterations of the loop. | |
1002 | ||
1003 | Input: | |
1004 | - LOOP: the loop to be peeled. | |
1005 | - E: the exit or entry edge of LOOP. | |
1006 | If it is the entry edge, we peel the first iterations of LOOP. In this | |
1007 | case first-loop is LOOP, and second-loop is the newly created loop. | |
1008 | If it is the exit edge, we peel the last iterations of LOOP. In this | |
1009 | case, first-loop is the newly created loop, and second-loop is LOOP. | |
1010 | - NITERS: the number of iterations that LOOP iterates. | |
1011 | - FIRST_NITERS: the number of iterations that the first-loop should iterate. | |
1012 | - UPDATE_FIRST_LOOP_COUNT: specified whether this function is responsible | |
1013 | for updating the loop bound of the first-loop to FIRST_NITERS. If it | |
1014 | is false, the caller of this function may want to take care of this | |
1015 | (this can be useful if we don't want new stmts added to first-loop). | |
1016 | - TH: cost model profitability threshold of iterations for vectorization. | |
1017 | - CHECK_PROFITABILITY: specify whether cost model check has not occurred | |
1018 | during versioning and hence needs to occur during | |
48e1416a | 1019 | prologue generation or whether cost model check |
fb85abff | 1020 | has not occurred during prologue generation and hence |
1021 | needs to occur during epilogue generation. | |
877584e4 | 1022 | - BOUND1 is the upper bound on number of iterations of the first loop (if known) |
1023 | - BOUND2 is the upper bound on number of iterations of the second loop (if known) | |
48e1416a | 1024 | |
fb85abff | 1025 | |
1026 | Output: | |
1027 | The function returns a pointer to the new loop-copy, or NULL if it failed | |
1028 | to perform the transformation. | |
1029 | ||
1030 | The function generates two if-then-else guards: one before the first loop, | |
1031 | and the other before the second loop: | |
1032 | The first guard is: | |
1033 | if (FIRST_NITERS == 0) then skip the first loop, | |
1034 | and go directly to the second loop. | |
1035 | The second guard is: | |
1036 | if (FIRST_NITERS == NITERS) then skip the second loop. | |
1037 | ||
23a3430d | 1038 | If the optional COND_EXPR and COND_EXPR_STMT_LIST arguments are given |
1039 | then the generated condition is combined with COND_EXPR and the | |
1040 | statements in COND_EXPR_STMT_LIST are emitted together with it. | |
1041 | ||
fb85abff | 1042 | FORNOW only simple loops are supported (see slpeel_can_duplicate_loop_p). |
1043 | FORNOW the resulting code will not be in loop-closed-ssa form. | |
1044 | */ | |
1045 | ||
1046 | static struct loop* | |
48e1416a | 1047 | slpeel_tree_peel_loop_to_edge (struct loop *loop, |
2f630015 | 1048 | edge e, tree *first_niters, |
fb85abff | 1049 | tree niters, bool update_first_loop_count, |
23a3430d | 1050 | unsigned int th, bool check_profitability, |
877584e4 | 1051 | tree cond_expr, gimple_seq cond_expr_stmt_list, |
1052 | int bound1, int bound2) | |
fb85abff | 1053 | { |
1054 | struct loop *new_loop = NULL, *first_loop, *second_loop; | |
1055 | edge skip_e; | |
1056 | tree pre_condition = NULL_TREE; | |
fb85abff | 1057 | basic_block bb_before_second_loop, bb_after_second_loop; |
1058 | basic_block bb_before_first_loop; | |
1059 | basic_block bb_between_loops; | |
1060 | basic_block new_exit_bb; | |
38091110 | 1061 | gimple_stmt_iterator gsi; |
fb85abff | 1062 | edge exit_e = single_exit (loop); |
36f39b2e | 1063 | source_location loop_loc; |
fb85abff | 1064 | tree cost_pre_condition = NULL_TREE; |
877584e4 | 1065 | /* There are many aspects to how likely the first loop is going to be executed. |
1066 | Without histogram we can't really do good job. Simply set it to | |
1067 | 2/3, so the first loop is not reordered to the end of function and | |
1068 | the hot path through stays short. */ | |
1069 | int first_guard_probability = 2 * REG_BR_PROB_BASE / 3; | |
1070 | int second_guard_probability = 2 * REG_BR_PROB_BASE / 3; | |
1071 | int probability_of_second_loop; | |
48e1416a | 1072 | |
fb85abff | 1073 | if (!slpeel_can_duplicate_loop_p (loop, e)) |
1074 | return NULL; | |
48e1416a | 1075 | |
f68f7ce8 | 1076 | /* We might have a queued need to update virtual SSA form. As we |
1077 | delete the update SSA machinery below after doing a regular | |
1078 | incremental SSA update during loop copying make sure we don't | |
1079 | lose that fact. | |
1080 | ??? Needing to update virtual SSA form by renaming is unfortunate | |
1081 | but not all of the vectorizer code inserting new loads / stores | |
1082 | properly assigns virtual operands to those statements. */ | |
1083 | update_ssa (TODO_update_ssa_only_virtuals); | |
1084 | ||
38091110 | 1085 | /* If the loop has a virtual PHI, but exit bb doesn't, create a virtual PHI |
1086 | in the exit bb and rename all the uses after the loop. This simplifies | |
1087 | the *guard[12] routines, which assume loop closed SSA form for all PHIs | |
1088 | (but normally loop closed SSA form doesn't require virtual PHIs to be | |
1089 | in the same form). Doing this early simplifies the checking what | |
1090 | uses should be renamed. */ | |
1091 | for (gsi = gsi_start_phis (loop->header); !gsi_end_p (gsi); gsi_next (&gsi)) | |
7c782c9b | 1092 | if (virtual_operand_p (gimple_phi_result (gsi_stmt (gsi)))) |
38091110 | 1093 | { |
1094 | gimple phi = gsi_stmt (gsi); | |
1095 | for (gsi = gsi_start_phis (exit_e->dest); | |
1096 | !gsi_end_p (gsi); gsi_next (&gsi)) | |
7c782c9b | 1097 | if (virtual_operand_p (gimple_phi_result (gsi_stmt (gsi)))) |
38091110 | 1098 | break; |
1099 | if (gsi_end_p (gsi)) | |
1100 | { | |
874117c8 | 1101 | tree new_vop = copy_ssa_name (PHI_RESULT (phi), NULL); |
1102 | gimple new_phi = create_phi_node (new_vop, exit_e->dest); | |
38091110 | 1103 | tree vop = PHI_ARG_DEF_FROM_EDGE (phi, EDGE_SUCC (loop->latch, 0)); |
1104 | imm_use_iterator imm_iter; | |
1105 | gimple stmt; | |
38091110 | 1106 | use_operand_p use_p; |
1107 | ||
60d535d2 | 1108 | add_phi_arg (new_phi, vop, exit_e, UNKNOWN_LOCATION); |
38091110 | 1109 | gimple_phi_set_result (new_phi, new_vop); |
1110 | FOR_EACH_IMM_USE_STMT (stmt, imm_iter, vop) | |
1111 | if (stmt != new_phi && gimple_bb (stmt) != loop->header) | |
1112 | FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter) | |
1113 | SET_USE (use_p, new_vop); | |
1114 | } | |
1115 | break; | |
1116 | } | |
fb85abff | 1117 | |
1118 | /* 1. Generate a copy of LOOP and put it on E (E is the entry/exit of LOOP). | |
1119 | Resulting CFG would be: | |
1120 | ||
1121 | first_loop: | |
1122 | do { | |
1123 | } while ... | |
1124 | ||
1125 | second_loop: | |
1126 | do { | |
1127 | } while ... | |
1128 | ||
1129 | orig_exit_bb: | |
1130 | */ | |
48e1416a | 1131 | |
fb85abff | 1132 | if (!(new_loop = slpeel_tree_duplicate_loop_to_edge_cfg (loop, e))) |
1133 | { | |
1134 | loop_loc = find_loop_location (loop); | |
7bd765d4 | 1135 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, loop_loc, |
1136 | "tree_duplicate_loop_to_edge_cfg failed.\n"); | |
fb85abff | 1137 | return NULL; |
1138 | } | |
48e1416a | 1139 | |
b123eaab | 1140 | if (MAY_HAVE_DEBUG_STMTS) |
1141 | { | |
f1f41a6c | 1142 | gcc_assert (!adjust_vec.exists ()); |
d70aebca | 1143 | adjust_vec.create (32); |
b123eaab | 1144 | } |
1145 | ||
fb85abff | 1146 | if (e == exit_e) |
1147 | { | |
1148 | /* NEW_LOOP was placed after LOOP. */ | |
1149 | first_loop = loop; | |
1150 | second_loop = new_loop; | |
1151 | } | |
1152 | else | |
1153 | { | |
1154 | /* NEW_LOOP was placed before LOOP. */ | |
1155 | first_loop = new_loop; | |
1156 | second_loop = loop; | |
1157 | } | |
1158 | ||
fb85abff | 1159 | /* 2. Add the guard code in one of the following ways: |
1160 | ||
1161 | 2.a Add the guard that controls whether the first loop is executed. | |
1162 | This occurs when this function is invoked for prologue or epilogue | |
1163 | generation and when the cost model check can be done at compile time. | |
1164 | ||
1165 | Resulting CFG would be: | |
1166 | ||
1167 | bb_before_first_loop: | |
1168 | if (FIRST_NITERS == 0) GOTO bb_before_second_loop | |
1169 | GOTO first-loop | |
1170 | ||
1171 | first_loop: | |
1172 | do { | |
1173 | } while ... | |
1174 | ||
1175 | bb_before_second_loop: | |
1176 | ||
1177 | second_loop: | |
1178 | do { | |
1179 | } while ... | |
1180 | ||
1181 | orig_exit_bb: | |
1182 | ||
1183 | 2.b Add the cost model check that allows the prologue | |
1184 | to iterate for the entire unchanged scalar | |
1185 | iterations of the loop in the event that the cost | |
1186 | model indicates that the scalar loop is more | |
1187 | profitable than the vector one. This occurs when | |
1188 | this function is invoked for prologue generation | |
1189 | and the cost model check needs to be done at run | |
1190 | time. | |
1191 | ||
1192 | Resulting CFG after prologue peeling would be: | |
1193 | ||
1194 | if (scalar_loop_iterations <= th) | |
1195 | FIRST_NITERS = scalar_loop_iterations | |
1196 | ||
1197 | bb_before_first_loop: | |
1198 | if (FIRST_NITERS == 0) GOTO bb_before_second_loop | |
1199 | GOTO first-loop | |
1200 | ||
1201 | first_loop: | |
1202 | do { | |
1203 | } while ... | |
1204 | ||
1205 | bb_before_second_loop: | |
1206 | ||
1207 | second_loop: | |
1208 | do { | |
1209 | } while ... | |
1210 | ||
1211 | orig_exit_bb: | |
1212 | ||
1213 | 2.c Add the cost model check that allows the epilogue | |
1214 | to iterate for the entire unchanged scalar | |
1215 | iterations of the loop in the event that the cost | |
1216 | model indicates that the scalar loop is more | |
1217 | profitable than the vector one. This occurs when | |
1218 | this function is invoked for epilogue generation | |
1219 | and the cost model check needs to be done at run | |
23a3430d | 1220 | time. This check is combined with any pre-existing |
1221 | check in COND_EXPR to avoid versioning. | |
fb85abff | 1222 | |
1223 | Resulting CFG after prologue peeling would be: | |
1224 | ||
1225 | bb_before_first_loop: | |
1226 | if ((scalar_loop_iterations <= th) | |
1227 | || | |
1228 | FIRST_NITERS == 0) GOTO bb_before_second_loop | |
1229 | GOTO first-loop | |
1230 | ||
1231 | first_loop: | |
1232 | do { | |
1233 | } while ... | |
1234 | ||
1235 | bb_before_second_loop: | |
1236 | ||
1237 | second_loop: | |
1238 | do { | |
1239 | } while ... | |
1240 | ||
1241 | orig_exit_bb: | |
1242 | */ | |
1243 | ||
1244 | bb_before_first_loop = split_edge (loop_preheader_edge (first_loop)); | |
c9b2c569 | 1245 | /* Loop copying insterted a forwarder block for us here. */ |
1246 | bb_before_second_loop = single_exit (first_loop)->dest; | |
fb85abff | 1247 | |
877584e4 | 1248 | probability_of_second_loop = (inverse_probability (first_guard_probability) |
1249 | + combine_probabilities (second_guard_probability, | |
1250 | first_guard_probability)); | |
1251 | /* Theoretically preheader edge of first loop and exit edge should have | |
1252 | same frequencies. Loop exit probablities are however easy to get wrong. | |
1253 | It is safer to copy value from original loop entry. */ | |
1254 | bb_before_second_loop->frequency | |
f9d4b7f4 | 1255 | = combine_probabilities (bb_before_first_loop->frequency, |
1256 | probability_of_second_loop); | |
877584e4 | 1257 | bb_before_second_loop->count |
1258 | = apply_probability (bb_before_first_loop->count, | |
1259 | probability_of_second_loop); | |
1260 | single_succ_edge (bb_before_second_loop)->count | |
1261 | = bb_before_second_loop->count; | |
1262 | ||
fb85abff | 1263 | /* Epilogue peeling. */ |
1264 | if (!update_first_loop_count) | |
1265 | { | |
1266 | pre_condition = | |
2f630015 | 1267 | fold_build2 (LE_EXPR, boolean_type_node, *first_niters, |
1268 | build_int_cst (TREE_TYPE (*first_niters), 0)); | |
fb85abff | 1269 | if (check_profitability) |
1270 | { | |
1271 | tree scalar_loop_iters | |
1272 | = unshare_expr (LOOP_VINFO_NITERS_UNCHANGED | |
1273 | (loop_vec_info_for_loop (loop))); | |
48e1416a | 1274 | cost_pre_condition = |
1275 | fold_build2 (LE_EXPR, boolean_type_node, scalar_loop_iters, | |
fb85abff | 1276 | build_int_cst (TREE_TYPE (scalar_loop_iters), th)); |
1277 | ||
1278 | pre_condition = fold_build2 (TRUTH_OR_EXPR, boolean_type_node, | |
1279 | cost_pre_condition, pre_condition); | |
1280 | } | |
23a3430d | 1281 | if (cond_expr) |
1282 | { | |
1283 | pre_condition = | |
1284 | fold_build2 (TRUTH_OR_EXPR, boolean_type_node, | |
1285 | pre_condition, | |
1286 | fold_build1 (TRUTH_NOT_EXPR, boolean_type_node, | |
1287 | cond_expr)); | |
1288 | } | |
fb85abff | 1289 | } |
1290 | ||
48e1416a | 1291 | /* Prologue peeling. */ |
fb85abff | 1292 | else |
1293 | { | |
1294 | if (check_profitability) | |
1295 | set_prologue_iterations (bb_before_first_loop, first_niters, | |
877584e4 | 1296 | loop, th, first_guard_probability); |
fb85abff | 1297 | |
1298 | pre_condition = | |
2f630015 | 1299 | fold_build2 (LE_EXPR, boolean_type_node, *first_niters, |
1300 | build_int_cst (TREE_TYPE (*first_niters), 0)); | |
fb85abff | 1301 | } |
1302 | ||
1303 | skip_e = slpeel_add_loop_guard (bb_before_first_loop, pre_condition, | |
23a3430d | 1304 | cond_expr_stmt_list, |
877584e4 | 1305 | bb_before_second_loop, bb_before_first_loop, |
1306 | inverse_probability (first_guard_probability)); | |
1307 | scale_loop_profile (first_loop, first_guard_probability, | |
1308 | check_profitability && (int)th > bound1 ? th : bound1); | |
fb85abff | 1309 | slpeel_update_phi_nodes_for_guard1 (skip_e, first_loop, |
1310 | first_loop == new_loop, | |
1e8cf080 | 1311 | &new_exit_bb); |
fb85abff | 1312 | |
1313 | ||
1314 | /* 3. Add the guard that controls whether the second loop is executed. | |
1315 | Resulting CFG would be: | |
1316 | ||
1317 | bb_before_first_loop: | |
1318 | if (FIRST_NITERS == 0) GOTO bb_before_second_loop (skip first loop) | |
1319 | GOTO first-loop | |
1320 | ||
1321 | first_loop: | |
1322 | do { | |
1323 | } while ... | |
1324 | ||
1325 | bb_between_loops: | |
1326 | if (FIRST_NITERS == NITERS) GOTO bb_after_second_loop (skip second loop) | |
1327 | GOTO bb_before_second_loop | |
1328 | ||
1329 | bb_before_second_loop: | |
1330 | ||
1331 | second_loop: | |
1332 | do { | |
1333 | } while ... | |
1334 | ||
1335 | bb_after_second_loop: | |
1336 | ||
1337 | orig_exit_bb: | |
1338 | */ | |
1339 | ||
1340 | bb_between_loops = new_exit_bb; | |
1341 | bb_after_second_loop = split_edge (single_exit (second_loop)); | |
1342 | ||
48e1416a | 1343 | pre_condition = |
2f630015 | 1344 | fold_build2 (EQ_EXPR, boolean_type_node, *first_niters, niters); |
23a3430d | 1345 | skip_e = slpeel_add_loop_guard (bb_between_loops, pre_condition, NULL, |
877584e4 | 1346 | bb_after_second_loop, bb_before_first_loop, |
1347 | inverse_probability (second_guard_probability)); | |
1348 | scale_loop_profile (second_loop, probability_of_second_loop, bound2); | |
fb85abff | 1349 | slpeel_update_phi_nodes_for_guard2 (skip_e, second_loop, |
1350 | second_loop == new_loop, &new_exit_bb); | |
1351 | ||
1352 | /* 4. Make first-loop iterate FIRST_NITERS times, if requested. | |
1353 | */ | |
1354 | if (update_first_loop_count) | |
2f630015 | 1355 | slpeel_make_loop_iterate_ntimes (first_loop, *first_niters); |
fb85abff | 1356 | |
5d206f11 | 1357 | delete_update_ssa (); |
1358 | ||
b123eaab | 1359 | adjust_vec_debug_stmts (); |
1360 | ||
fb85abff | 1361 | return new_loop; |
1362 | } | |
1363 | ||
1364 | /* Function vect_get_loop_location. | |
1365 | ||
1366 | Extract the location of the loop in the source code. | |
1367 | If the loop is not well formed for vectorization, an estimated | |
1368 | location is calculated. | |
1369 | Return the loop location if succeed and NULL if not. */ | |
1370 | ||
36f39b2e | 1371 | source_location |
fb85abff | 1372 | find_loop_location (struct loop *loop) |
1373 | { | |
1374 | gimple stmt = NULL; | |
1375 | basic_block bb; | |
1376 | gimple_stmt_iterator si; | |
1377 | ||
1378 | if (!loop) | |
36f39b2e | 1379 | return UNKNOWN_LOCATION; |
fb85abff | 1380 | |
1381 | stmt = get_loop_exit_condition (loop); | |
1382 | ||
b2d978a6 | 1383 | if (stmt |
1384 | && LOCATION_LOCUS (gimple_location (stmt)) > BUILTINS_LOCATION) | |
fb85abff | 1385 | return gimple_location (stmt); |
1386 | ||
1387 | /* If we got here the loop is probably not "well formed", | |
1388 | try to estimate the loop location */ | |
1389 | ||
1390 | if (!loop->header) | |
36f39b2e | 1391 | return UNKNOWN_LOCATION; |
fb85abff | 1392 | |
1393 | bb = loop->header; | |
1394 | ||
1395 | for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si)) | |
1396 | { | |
1397 | stmt = gsi_stmt (si); | |
b2d978a6 | 1398 | if (LOCATION_LOCUS (gimple_location (stmt)) > BUILTINS_LOCATION) |
fb85abff | 1399 | return gimple_location (stmt); |
1400 | } | |
1401 | ||
36f39b2e | 1402 | return UNKNOWN_LOCATION; |
fb85abff | 1403 | } |
1404 | ||
1405 | ||
fb85abff | 1406 | /* Function vect_can_advance_ivs_p |
1407 | ||
48e1416a | 1408 | In case the number of iterations that LOOP iterates is unknown at compile |
1409 | time, an epilog loop will be generated, and the loop induction variables | |
1410 | (IVs) will be "advanced" to the value they are supposed to take just before | |
fb85abff | 1411 | the epilog loop. Here we check that the access function of the loop IVs |
1412 | and the expression that represents the loop bound are simple enough. | |
1413 | These restrictions will be relaxed in the future. */ | |
1414 | ||
48e1416a | 1415 | bool |
fb85abff | 1416 | vect_can_advance_ivs_p (loop_vec_info loop_vinfo) |
1417 | { | |
1418 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); | |
1419 | basic_block bb = loop->header; | |
1420 | gimple phi; | |
1421 | gimple_stmt_iterator gsi; | |
1422 | ||
1423 | /* Analyze phi functions of the loop header. */ | |
1424 | ||
6d8fb6cf | 1425 | if (dump_enabled_p ()) |
78bb46f5 | 1426 | dump_printf_loc (MSG_NOTE, vect_location, "vect_can_advance_ivs_p:\n"); |
fb85abff | 1427 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
1428 | { | |
fb85abff | 1429 | tree evolution_part; |
1430 | ||
1431 | phi = gsi_stmt (gsi); | |
6d8fb6cf | 1432 | if (dump_enabled_p ()) |
fb85abff | 1433 | { |
7bd765d4 | 1434 | dump_printf_loc (MSG_NOTE, vect_location, "Analyze phi: "); |
1435 | dump_gimple_stmt (MSG_NOTE, TDF_SLIM, phi, 0); | |
78bb46f5 | 1436 | dump_printf (MSG_NOTE, "\n"); |
fb85abff | 1437 | } |
1438 | ||
1439 | /* Skip virtual phi's. The data dependences that are associated with | |
1440 | virtual defs/uses (i.e., memory accesses) are analyzed elsewhere. */ | |
1441 | ||
7c782c9b | 1442 | if (virtual_operand_p (PHI_RESULT (phi))) |
fb85abff | 1443 | { |
6d8fb6cf | 1444 | if (dump_enabled_p ()) |
7bd765d4 | 1445 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, |
78bb46f5 | 1446 | "virtual phi. skip.\n"); |
fb85abff | 1447 | continue; |
1448 | } | |
1449 | ||
1450 | /* Skip reduction phis. */ | |
1451 | ||
1452 | if (STMT_VINFO_DEF_TYPE (vinfo_for_stmt (phi)) == vect_reduction_def) | |
1453 | { | |
6d8fb6cf | 1454 | if (dump_enabled_p ()) |
7bd765d4 | 1455 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, |
78bb46f5 | 1456 | "reduc phi. skip.\n"); |
fb85abff | 1457 | continue; |
1458 | } | |
1459 | ||
1460 | /* Analyze the evolution function. */ | |
1461 | ||
2cd0995e | 1462 | evolution_part |
1463 | = STMT_VINFO_LOOP_PHI_EVOLUTION_PART (vinfo_for_stmt (phi)); | |
fb85abff | 1464 | if (evolution_part == NULL_TREE) |
1465 | { | |
6d8fb6cf | 1466 | if (dump_enabled_p ()) |
2cd0995e | 1467 | dump_printf (MSG_MISSED_OPTIMIZATION, |
78bb46f5 | 1468 | "No access function or evolution.\n"); |
fb85abff | 1469 | return false; |
1470 | } | |
48e1416a | 1471 | |
1472 | /* FORNOW: We do not transform initial conditions of IVs | |
fb85abff | 1473 | which evolution functions are a polynomial of degree >= 2. */ |
1474 | ||
1475 | if (tree_is_chrec (evolution_part)) | |
48e1416a | 1476 | return false; |
fb85abff | 1477 | } |
1478 | ||
1479 | return true; | |
1480 | } | |
1481 | ||
1482 | ||
1483 | /* Function vect_update_ivs_after_vectorizer. | |
1484 | ||
1485 | "Advance" the induction variables of LOOP to the value they should take | |
1486 | after the execution of LOOP. This is currently necessary because the | |
1487 | vectorizer does not handle induction variables that are used after the | |
1488 | loop. Such a situation occurs when the last iterations of LOOP are | |
1489 | peeled, because: | |
1490 | 1. We introduced new uses after LOOP for IVs that were not originally used | |
1491 | after LOOP: the IVs of LOOP are now used by an epilog loop. | |
1492 | 2. LOOP is going to be vectorized; this means that it will iterate N/VF | |
1493 | times, whereas the loop IVs should be bumped N times. | |
1494 | ||
1495 | Input: | |
1496 | - LOOP - a loop that is going to be vectorized. The last few iterations | |
1497 | of LOOP were peeled. | |
1498 | - NITERS - the number of iterations that LOOP executes (before it is | |
1499 | vectorized). i.e, the number of times the ivs should be bumped. | |
1500 | - UPDATE_E - a successor edge of LOOP->exit that is on the (only) path | |
1501 | coming out from LOOP on which there are uses of the LOOP ivs | |
1502 | (this is the path from LOOP->exit to epilog_loop->preheader). | |
1503 | ||
1504 | The new definitions of the ivs are placed in LOOP->exit. | |
1505 | The phi args associated with the edge UPDATE_E in the bb | |
1506 | UPDATE_E->dest are updated accordingly. | |
1507 | ||
1508 | Assumption 1: Like the rest of the vectorizer, this function assumes | |
1509 | a single loop exit that has a single predecessor. | |
1510 | ||
1511 | Assumption 2: The phi nodes in the LOOP header and in update_bb are | |
1512 | organized in the same order. | |
1513 | ||
1514 | Assumption 3: The access function of the ivs is simple enough (see | |
1515 | vect_can_advance_ivs_p). This assumption will be relaxed in the future. | |
1516 | ||
1517 | Assumption 4: Exactly one of the successors of LOOP exit-bb is on a path | |
48e1416a | 1518 | coming out of LOOP on which the ivs of LOOP are used (this is the path |
fb85abff | 1519 | that leads to the epilog loop; other paths skip the epilog loop). This |
1520 | path starts with the edge UPDATE_E, and its destination (denoted update_bb) | |
1521 | needs to have its phis updated. | |
1522 | */ | |
1523 | ||
1524 | static void | |
48e1416a | 1525 | vect_update_ivs_after_vectorizer (loop_vec_info loop_vinfo, tree niters, |
fb85abff | 1526 | edge update_e) |
1527 | { | |
1528 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); | |
1529 | basic_block exit_bb = single_exit (loop)->dest; | |
1530 | gimple phi, phi1; | |
1531 | gimple_stmt_iterator gsi, gsi1; | |
1532 | basic_block update_bb = update_e->dest; | |
1533 | ||
f3d6d99e | 1534 | gcc_checking_assert (vect_can_advance_ivs_p (loop_vinfo)); |
fb85abff | 1535 | |
1536 | /* Make sure there exists a single-predecessor exit bb: */ | |
1537 | gcc_assert (single_pred_p (exit_bb)); | |
1538 | ||
1539 | for (gsi = gsi_start_phis (loop->header), gsi1 = gsi_start_phis (update_bb); | |
1540 | !gsi_end_p (gsi) && !gsi_end_p (gsi1); | |
1541 | gsi_next (&gsi), gsi_next (&gsi1)) | |
1542 | { | |
fb85abff | 1543 | tree init_expr; |
1efcacec | 1544 | tree step_expr, off; |
1545 | tree type; | |
fb85abff | 1546 | tree var, ni, ni_name; |
1547 | gimple_stmt_iterator last_gsi; | |
86faead7 | 1548 | stmt_vec_info stmt_info; |
fb85abff | 1549 | |
1550 | phi = gsi_stmt (gsi); | |
1551 | phi1 = gsi_stmt (gsi1); | |
6d8fb6cf | 1552 | if (dump_enabled_p ()) |
fb85abff | 1553 | { |
7bd765d4 | 1554 | dump_printf_loc (MSG_NOTE, vect_location, |
1555 | "vect_update_ivs_after_vectorizer: phi: "); | |
1556 | dump_gimple_stmt (MSG_NOTE, TDF_SLIM, phi, 0); | |
78bb46f5 | 1557 | dump_printf (MSG_NOTE, "\n"); |
fb85abff | 1558 | } |
1559 | ||
1560 | /* Skip virtual phi's. */ | |
7c782c9b | 1561 | if (virtual_operand_p (PHI_RESULT (phi))) |
fb85abff | 1562 | { |
6d8fb6cf | 1563 | if (dump_enabled_p ()) |
7bd765d4 | 1564 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, |
78bb46f5 | 1565 | "virtual phi. skip.\n"); |
fb85abff | 1566 | continue; |
1567 | } | |
1568 | ||
1569 | /* Skip reduction phis. */ | |
86faead7 | 1570 | stmt_info = vinfo_for_stmt (phi); |
1571 | if (STMT_VINFO_DEF_TYPE (stmt_info) == vect_reduction_def) | |
48e1416a | 1572 | { |
6d8fb6cf | 1573 | if (dump_enabled_p ()) |
7bd765d4 | 1574 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, |
78bb46f5 | 1575 | "reduc phi. skip.\n"); |
fb85abff | 1576 | continue; |
48e1416a | 1577 | } |
fb85abff | 1578 | |
86faead7 | 1579 | type = TREE_TYPE (gimple_phi_result (phi)); |
1580 | step_expr = STMT_VINFO_LOOP_PHI_EVOLUTION_PART (stmt_info); | |
1581 | step_expr = unshare_expr (step_expr); | |
48e1416a | 1582 | |
fb85abff | 1583 | /* FORNOW: We do not support IVs whose evolution function is a polynomial |
1584 | of degree >= 2 or exponential. */ | |
86faead7 | 1585 | gcc_assert (!tree_is_chrec (step_expr)); |
fb85abff | 1586 | |
86faead7 | 1587 | init_expr = PHI_ARG_DEF_FROM_EDGE (phi, loop_preheader_edge (loop)); |
fb85abff | 1588 | |
1efcacec | 1589 | off = fold_build2 (MULT_EXPR, TREE_TYPE (step_expr), |
1590 | fold_convert (TREE_TYPE (step_expr), niters), | |
1591 | step_expr); | |
86faead7 | 1592 | if (POINTER_TYPE_P (type)) |
2cc66f2a | 1593 | ni = fold_build_pointer_plus (init_expr, off); |
fb85abff | 1594 | else |
86faead7 | 1595 | ni = fold_build2 (PLUS_EXPR, type, |
1596 | init_expr, fold_convert (type, off)); | |
fb85abff | 1597 | |
86faead7 | 1598 | var = create_tmp_var (type, "tmp"); |
fb85abff | 1599 | |
1600 | last_gsi = gsi_last_bb (exit_bb); | |
1601 | ni_name = force_gimple_operand_gsi (&last_gsi, ni, false, var, | |
1602 | true, GSI_SAME_STMT); | |
48e1416a | 1603 | |
fb85abff | 1604 | /* Fix phi expressions in the successor bb. */ |
b123eaab | 1605 | adjust_phi_and_debug_stmts (phi1, update_e, ni_name); |
fb85abff | 1606 | } |
1607 | } | |
1608 | ||
fb85abff | 1609 | /* Function vect_do_peeling_for_loop_bound |
1610 | ||
1611 | Peel the last iterations of the loop represented by LOOP_VINFO. | |
48e1416a | 1612 | The peeled iterations form a new epilog loop. Given that the loop now |
fb85abff | 1613 | iterates NITERS times, the new epilog loop iterates |
1614 | NITERS % VECTORIZATION_FACTOR times. | |
48e1416a | 1615 | |
1616 | The original loop will later be made to iterate | |
23a3430d | 1617 | NITERS / VECTORIZATION_FACTOR times (this value is placed into RATIO). |
1618 | ||
1619 | COND_EXPR and COND_EXPR_STMT_LIST are combined with a new generated | |
1620 | test. */ | |
fb85abff | 1621 | |
48e1416a | 1622 | void |
782fd1d1 | 1623 | vect_do_peeling_for_loop_bound (loop_vec_info loop_vinfo, |
1624 | tree ni_name, tree ratio_mult_vf_name, | |
e7430948 | 1625 | unsigned int th, bool check_profitability) |
fb85abff | 1626 | { |
fb85abff | 1627 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); |
1628 | struct loop *new_loop; | |
1629 | edge update_e; | |
1630 | basic_block preheader; | |
1631 | int loop_num; | |
2afdcbed | 1632 | int max_iter; |
e7430948 | 1633 | tree cond_expr = NULL_TREE; |
1634 | gimple_seq cond_expr_stmt_list = NULL; | |
fb85abff | 1635 | |
6d8fb6cf | 1636 | if (dump_enabled_p ()) |
b055bc88 | 1637 | dump_printf_loc (MSG_NOTE, vect_location, |
78bb46f5 | 1638 | "=== vect_do_peeling_for_loop_bound ===\n"); |
fb85abff | 1639 | |
1640 | initialize_original_copy_tables (); | |
1641 | ||
48e1416a | 1642 | loop_num = loop->num; |
fb85abff | 1643 | |
fb85abff | 1644 | new_loop = slpeel_tree_peel_loop_to_edge (loop, single_exit (loop), |
2f630015 | 1645 | &ratio_mult_vf_name, ni_name, false, |
23a3430d | 1646 | th, check_profitability, |
877584e4 | 1647 | cond_expr, cond_expr_stmt_list, |
1648 | 0, LOOP_VINFO_VECT_FACTOR (loop_vinfo)); | |
fb85abff | 1649 | gcc_assert (new_loop); |
1650 | gcc_assert (loop_num == loop->num); | |
1651 | #ifdef ENABLE_CHECKING | |
1652 | slpeel_verify_cfg_after_peeling (loop, new_loop); | |
1653 | #endif | |
1654 | ||
1655 | /* A guard that controls whether the new_loop is to be executed or skipped | |
1656 | is placed in LOOP->exit. LOOP->exit therefore has two successors - one | |
1657 | is the preheader of NEW_LOOP, where the IVs from LOOP are used. The other | |
1658 | is a bb after NEW_LOOP, where these IVs are not used. Find the edge that | |
1659 | is on the path where the LOOP IVs are used and need to be updated. */ | |
1660 | ||
1661 | preheader = loop_preheader_edge (new_loop)->src; | |
1662 | if (EDGE_PRED (preheader, 0)->src == single_exit (loop)->dest) | |
1663 | update_e = EDGE_PRED (preheader, 0); | |
1664 | else | |
1665 | update_e = EDGE_PRED (preheader, 1); | |
1666 | ||
48e1416a | 1667 | /* Update IVs of original loop as if they were advanced |
fb85abff | 1668 | by ratio_mult_vf_name steps. */ |
48e1416a | 1669 | vect_update_ivs_after_vectorizer (loop_vinfo, ratio_mult_vf_name, update_e); |
fb85abff | 1670 | |
d3f1934c | 1671 | /* For vectorization factor N, we need to copy last N-1 values in epilogue |
1672 | and this means N-2 loopback edge executions. | |
1673 | ||
1674 | PEELING_FOR_GAPS works by subtracting last iteration and thus the epilogue | |
1675 | will execute at least LOOP_VINFO_VECT_FACTOR times. */ | |
1676 | max_iter = (LOOP_VINFO_PEELING_FOR_GAPS (loop_vinfo) | |
1677 | ? LOOP_VINFO_VECT_FACTOR (loop_vinfo) * 2 | |
1678 | : LOOP_VINFO_VECT_FACTOR (loop_vinfo)) - 2; | |
e7430948 | 1679 | if (check_profitability) |
d3f1934c | 1680 | max_iter = MAX (max_iter, (int) th - 1); |
cf8f0e63 | 1681 | record_niter_bound (new_loop, double_int::from_shwi (max_iter), false, true); |
b055bc88 | 1682 | dump_printf (MSG_NOTE, |
7bd765d4 | 1683 | "Setting upper bound of nb iterations for epilogue " |
1684 | "loop to %d\n", max_iter); | |
15fa0281 | 1685 | |
fb85abff | 1686 | /* After peeling we have to reset scalar evolution analyzer. */ |
1687 | scev_reset (); | |
1688 | ||
1689 | free_original_copy_tables (); | |
1690 | } | |
1691 | ||
1692 | ||
1693 | /* Function vect_gen_niters_for_prolog_loop | |
1694 | ||
1695 | Set the number of iterations for the loop represented by LOOP_VINFO | |
1696 | to the minimum between LOOP_NITERS (the original iteration count of the loop) | |
1697 | and the misalignment of DR - the data reference recorded in | |
48e1416a | 1698 | LOOP_VINFO_UNALIGNED_DR (LOOP_VINFO). As a result, after the execution of |
fb85abff | 1699 | this loop, the data reference DR will refer to an aligned location. |
1700 | ||
1701 | The following computation is generated: | |
1702 | ||
1703 | If the misalignment of DR is known at compile time: | |
1704 | addr_mis = int mis = DR_MISALIGNMENT (dr); | |
1705 | Else, compute address misalignment in bytes: | |
482a44fa | 1706 | addr_mis = addr & (vectype_align - 1) |
fb85abff | 1707 | |
1708 | prolog_niters = min (LOOP_NITERS, ((VF - addr_mis/elem_size)&(VF-1))/step) | |
1709 | ||
1710 | (elem_size = element type size; an element is the scalar element whose type | |
1711 | is the inner type of the vectype) | |
1712 | ||
1713 | When the step of the data-ref in the loop is not 1 (as in interleaved data | |
1714 | and SLP), the number of iterations of the prolog must be divided by the step | |
1715 | (which is equal to the size of interleaved group). | |
1716 | ||
1717 | The above formulas assume that VF == number of elements in the vector. This | |
1718 | may not hold when there are multiple-types in the loop. | |
1719 | In this case, for some data-references in the loop the VF does not represent | |
1720 | the number of elements that fit in the vector. Therefore, instead of VF we | |
1721 | use TYPE_VECTOR_SUBPARTS. */ | |
1722 | ||
48e1416a | 1723 | static tree |
877584e4 | 1724 | vect_gen_niters_for_prolog_loop (loop_vec_info loop_vinfo, tree loop_niters, int *bound) |
fb85abff | 1725 | { |
1726 | struct data_reference *dr = LOOP_VINFO_UNALIGNED_DR (loop_vinfo); | |
1727 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); | |
1728 | tree var; | |
1729 | gimple_seq stmts; | |
1730 | tree iters, iters_name; | |
1731 | edge pe; | |
1732 | basic_block new_bb; | |
1733 | gimple dr_stmt = DR_STMT (dr); | |
1734 | stmt_vec_info stmt_info = vinfo_for_stmt (dr_stmt); | |
1735 | tree vectype = STMT_VINFO_VECTYPE (stmt_info); | |
1736 | int vectype_align = TYPE_ALIGN (vectype) / BITS_PER_UNIT; | |
1737 | tree niters_type = TREE_TYPE (loop_niters); | |
fb85abff | 1738 | int nelements = TYPE_VECTOR_SUBPARTS (vectype); |
1739 | ||
48e1416a | 1740 | pe = loop_preheader_edge (loop); |
fb85abff | 1741 | |
313a5120 | 1742 | if (LOOP_VINFO_PEELING_FOR_ALIGNMENT (loop_vinfo) > 0) |
fb85abff | 1743 | { |
313a5120 | 1744 | int npeel = LOOP_VINFO_PEELING_FOR_ALIGNMENT (loop_vinfo); |
fb85abff | 1745 | |
6d8fb6cf | 1746 | if (dump_enabled_p ()) |
b055bc88 | 1747 | dump_printf_loc (MSG_NOTE, vect_location, |
78bb46f5 | 1748 | "known peeling = %d.\n", npeel); |
fb85abff | 1749 | |
0822b158 | 1750 | iters = build_int_cst (niters_type, npeel); |
313a5120 | 1751 | *bound = LOOP_VINFO_PEELING_FOR_ALIGNMENT (loop_vinfo); |
fb85abff | 1752 | } |
1753 | else | |
1754 | { | |
1755 | gimple_seq new_stmts = NULL; | |
f1b8c740 | 1756 | bool negative = tree_int_cst_compare (DR_STEP (dr), size_zero_node) < 0; |
1757 | tree offset = negative | |
1758 | ? size_int (-TYPE_VECTOR_SUBPARTS (vectype) + 1) : NULL_TREE; | |
48e1416a | 1759 | tree start_addr = vect_create_addr_base_for_vector_ref (dr_stmt, |
f1b8c740 | 1760 | &new_stmts, offset, loop); |
3cea8318 | 1761 | tree type = unsigned_type_for (TREE_TYPE (start_addr)); |
482a44fa | 1762 | tree vectype_align_minus_1 = build_int_cst (type, vectype_align - 1); |
1763 | HOST_WIDE_INT elem_size = | |
1764 | int_cst_value (TYPE_SIZE_UNIT (TREE_TYPE (vectype))); | |
1765 | tree elem_size_log = build_int_cst (type, exact_log2 (elem_size)); | |
fb85abff | 1766 | tree nelements_minus_1 = build_int_cst (type, nelements - 1); |
1767 | tree nelements_tree = build_int_cst (type, nelements); | |
1768 | tree byte_misalign; | |
1769 | tree elem_misalign; | |
1770 | ||
1771 | new_bb = gsi_insert_seq_on_edge_immediate (pe, new_stmts); | |
1772 | gcc_assert (!new_bb); | |
48e1416a | 1773 | |
482a44fa | 1774 | /* Create: byte_misalign = addr & (vectype_align - 1) */ |
48e1416a | 1775 | byte_misalign = |
0822b158 | 1776 | fold_build2 (BIT_AND_EXPR, type, fold_convert (type, start_addr), |
482a44fa | 1777 | vectype_align_minus_1); |
48e1416a | 1778 | |
fb85abff | 1779 | /* Create: elem_misalign = byte_misalign / element_size */ |
1780 | elem_misalign = | |
1781 | fold_build2 (RSHIFT_EXPR, type, byte_misalign, elem_size_log); | |
1782 | ||
1783 | /* Create: (niters_type) (nelements - elem_misalign)&(nelements - 1) */ | |
f1b8c740 | 1784 | if (negative) |
1785 | iters = fold_build2 (MINUS_EXPR, type, elem_misalign, nelements_tree); | |
1786 | else | |
1787 | iters = fold_build2 (MINUS_EXPR, type, nelements_tree, elem_misalign); | |
fb85abff | 1788 | iters = fold_build2 (BIT_AND_EXPR, type, iters, nelements_minus_1); |
1789 | iters = fold_convert (niters_type, iters); | |
877584e4 | 1790 | *bound = nelements; |
fb85abff | 1791 | } |
1792 | ||
1793 | /* Create: prolog_loop_niters = min (iters, loop_niters) */ | |
1794 | /* If the loop bound is known at compile time we already verified that it is | |
1795 | greater than vf; since the misalignment ('iters') is at most vf, there's | |
1796 | no need to generate the MIN_EXPR in this case. */ | |
1797 | if (TREE_CODE (loop_niters) != INTEGER_CST) | |
1798 | iters = fold_build2 (MIN_EXPR, niters_type, iters, loop_niters); | |
1799 | ||
6d8fb6cf | 1800 | if (dump_enabled_p ()) |
fb85abff | 1801 | { |
b055bc88 | 1802 | dump_printf_loc (MSG_NOTE, vect_location, |
7bd765d4 | 1803 | "niters for prolog loop: "); |
b055bc88 | 1804 | dump_generic_expr (MSG_NOTE, TDF_SLIM, iters); |
78bb46f5 | 1805 | dump_printf (MSG_NOTE, "\n"); |
fb85abff | 1806 | } |
1807 | ||
1808 | var = create_tmp_var (niters_type, "prolog_loop_niters"); | |
fb85abff | 1809 | stmts = NULL; |
1810 | iters_name = force_gimple_operand (iters, &stmts, false, var); | |
1811 | ||
1812 | /* Insert stmt on loop preheader edge. */ | |
1813 | if (stmts) | |
1814 | { | |
1815 | basic_block new_bb = gsi_insert_seq_on_edge_immediate (pe, stmts); | |
1816 | gcc_assert (!new_bb); | |
1817 | } | |
1818 | ||
48e1416a | 1819 | return iters_name; |
fb85abff | 1820 | } |
1821 | ||
1822 | ||
1823 | /* Function vect_update_init_of_dr | |
1824 | ||
1825 | NITERS iterations were peeled from LOOP. DR represents a data reference | |
1826 | in LOOP. This function updates the information recorded in DR to | |
48e1416a | 1827 | account for the fact that the first NITERS iterations had already been |
fb85abff | 1828 | executed. Specifically, it updates the OFFSET field of DR. */ |
1829 | ||
1830 | static void | |
1831 | vect_update_init_of_dr (struct data_reference *dr, tree niters) | |
1832 | { | |
1833 | tree offset = DR_OFFSET (dr); | |
48e1416a | 1834 | |
fb85abff | 1835 | niters = fold_build2 (MULT_EXPR, sizetype, |
1836 | fold_convert (sizetype, niters), | |
1837 | fold_convert (sizetype, DR_STEP (dr))); | |
87f9ffa4 | 1838 | offset = fold_build2 (PLUS_EXPR, sizetype, |
1839 | fold_convert (sizetype, offset), niters); | |
fb85abff | 1840 | DR_OFFSET (dr) = offset; |
1841 | } | |
1842 | ||
1843 | ||
1844 | /* Function vect_update_inits_of_drs | |
1845 | ||
48e1416a | 1846 | NITERS iterations were peeled from the loop represented by LOOP_VINFO. |
1847 | This function updates the information recorded for the data references in | |
1848 | the loop to account for the fact that the first NITERS iterations had | |
fb85abff | 1849 | already been executed. Specifically, it updates the initial_condition of |
1850 | the access_function of all the data_references in the loop. */ | |
1851 | ||
1852 | static void | |
1853 | vect_update_inits_of_drs (loop_vec_info loop_vinfo, tree niters) | |
1854 | { | |
1855 | unsigned int i; | |
f1f41a6c | 1856 | vec<data_reference_p> datarefs = LOOP_VINFO_DATAREFS (loop_vinfo); |
fb85abff | 1857 | struct data_reference *dr; |
7bd765d4 | 1858 | |
6d8fb6cf | 1859 | if (dump_enabled_p ()) |
b055bc88 | 1860 | dump_printf_loc (MSG_NOTE, vect_location, |
78bb46f5 | 1861 | "=== vect_update_inits_of_dr ===\n"); |
fb85abff | 1862 | |
f1f41a6c | 1863 | FOR_EACH_VEC_ELT (datarefs, i, dr) |
fb85abff | 1864 | vect_update_init_of_dr (dr, niters); |
1865 | } | |
1866 | ||
1867 | ||
1868 | /* Function vect_do_peeling_for_alignment | |
1869 | ||
1870 | Peel the first 'niters' iterations of the loop represented by LOOP_VINFO. | |
1871 | 'niters' is set to the misalignment of one of the data references in the | |
1872 | loop, thereby forcing it to refer to an aligned location at the beginning | |
1873 | of the execution of this loop. The data reference for which we are | |
1874 | peeling is recorded in LOOP_VINFO_UNALIGNED_DR. */ | |
1875 | ||
1876 | void | |
782fd1d1 | 1877 | vect_do_peeling_for_alignment (loop_vec_info loop_vinfo, tree ni_name, |
e7430948 | 1878 | unsigned int th, bool check_profitability) |
fb85abff | 1879 | { |
1880 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); | |
782fd1d1 | 1881 | tree niters_of_prolog_loop; |
be2e5c02 | 1882 | tree wide_prolog_niters; |
fb85abff | 1883 | struct loop *new_loop; |
b6556916 | 1884 | int max_iter; |
877584e4 | 1885 | int bound = 0; |
fb85abff | 1886 | |
6d8fb6cf | 1887 | if (dump_enabled_p ()) |
6ee2edad | 1888 | dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, vect_location, |
1889 | "loop peeled for vectorization to enhance" | |
1890 | " alignment\n"); | |
fb85abff | 1891 | |
1892 | initialize_original_copy_tables (); | |
1893 | ||
782fd1d1 | 1894 | gimple_seq stmts = NULL; |
1895 | gsi_insert_seq_on_edge_immediate (loop_preheader_edge (loop), stmts); | |
2f630015 | 1896 | niters_of_prolog_loop = vect_gen_niters_for_prolog_loop (loop_vinfo, |
877584e4 | 1897 | ni_name, |
1898 | &bound); | |
fb85abff | 1899 | |
fb85abff | 1900 | /* Peel the prolog loop and iterate it niters_of_prolog_loop. */ |
1901 | new_loop = | |
1902 | slpeel_tree_peel_loop_to_edge (loop, loop_preheader_edge (loop), | |
2f630015 | 1903 | &niters_of_prolog_loop, ni_name, true, |
877584e4 | 1904 | th, check_profitability, NULL_TREE, NULL, |
1905 | bound, | |
1906 | 0); | |
fb85abff | 1907 | |
1908 | gcc_assert (new_loop); | |
1909 | #ifdef ENABLE_CHECKING | |
1910 | slpeel_verify_cfg_after_peeling (new_loop, loop); | |
1911 | #endif | |
d3f1934c | 1912 | /* For vectorization factor N, we need to copy at most N-1 values |
1913 | for alignment and this means N-2 loopback edge executions. */ | |
1914 | max_iter = LOOP_VINFO_VECT_FACTOR (loop_vinfo) - 2; | |
e7430948 | 1915 | if (check_profitability) |
d3f1934c | 1916 | max_iter = MAX (max_iter, (int) th - 1); |
cf8f0e63 | 1917 | record_niter_bound (new_loop, double_int::from_shwi (max_iter), false, true); |
b055bc88 | 1918 | dump_printf (MSG_NOTE, |
7bd765d4 | 1919 | "Setting upper bound of nb iterations for prologue " |
1920 | "loop to %d\n", max_iter); | |
fb85abff | 1921 | |
1922 | /* Update number of times loop executes. */ | |
fb85abff | 1923 | LOOP_VINFO_NITERS (loop_vinfo) = fold_build2 (MINUS_EXPR, |
313a5120 | 1924 | TREE_TYPE (ni_name), ni_name, niters_of_prolog_loop); |
fb85abff | 1925 | |
2f630015 | 1926 | if (types_compatible_p (sizetype, TREE_TYPE (niters_of_prolog_loop))) |
1927 | wide_prolog_niters = niters_of_prolog_loop; | |
1928 | else | |
1929 | { | |
1930 | gimple_seq seq = NULL; | |
1931 | edge pe = loop_preheader_edge (loop); | |
1932 | tree wide_iters = fold_convert (sizetype, niters_of_prolog_loop); | |
1933 | tree var = create_tmp_var (sizetype, "prolog_loop_adjusted_niters"); | |
2f630015 | 1934 | wide_prolog_niters = force_gimple_operand (wide_iters, &seq, false, |
1935 | var); | |
1936 | if (seq) | |
1937 | { | |
1938 | /* Insert stmt on loop preheader edge. */ | |
1939 | basic_block new_bb = gsi_insert_seq_on_edge_immediate (pe, seq); | |
1940 | gcc_assert (!new_bb); | |
1941 | } | |
1942 | } | |
1943 | ||
fb85abff | 1944 | /* Update the init conditions of the access functions of all data refs. */ |
be2e5c02 | 1945 | vect_update_inits_of_drs (loop_vinfo, wide_prolog_niters); |
fb85abff | 1946 | |
1947 | /* After peeling we have to reset scalar evolution analyzer. */ | |
1948 | scev_reset (); | |
1949 | ||
1950 | free_original_copy_tables (); | |
1951 | } | |
1952 | ||
1953 | ||
1954 | /* Function vect_create_cond_for_align_checks. | |
1955 | ||
1956 | Create a conditional expression that represents the alignment checks for | |
1957 | all of data references (array element references) whose alignment must be | |
1958 | checked at runtime. | |
1959 | ||
1960 | Input: | |
1961 | COND_EXPR - input conditional expression. New conditions will be chained | |
1962 | with logical AND operation. | |
1963 | LOOP_VINFO - two fields of the loop information are used. | |
1964 | LOOP_VINFO_PTR_MASK is the mask used to check the alignment. | |
1965 | LOOP_VINFO_MAY_MISALIGN_STMTS contains the refs to be checked. | |
1966 | ||
1967 | Output: | |
1968 | COND_EXPR_STMT_LIST - statements needed to construct the conditional | |
1969 | expression. | |
1970 | The returned value is the conditional expression to be used in the if | |
1971 | statement that controls which version of the loop gets executed at runtime. | |
1972 | ||
1973 | The algorithm makes two assumptions: | |
1974 | 1) The number of bytes "n" in a vector is a power of 2. | |
1975 | 2) An address "a" is aligned if a%n is zero and that this | |
1976 | test can be done as a&(n-1) == 0. For example, for 16 | |
1977 | byte vectors the test is a&0xf == 0. */ | |
1978 | ||
1979 | static void | |
1980 | vect_create_cond_for_align_checks (loop_vec_info loop_vinfo, | |
1981 | tree *cond_expr, | |
1982 | gimple_seq *cond_expr_stmt_list) | |
1983 | { | |
1984 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); | |
f1f41a6c | 1985 | vec<gimple> may_misalign_stmts |
fb85abff | 1986 | = LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo); |
1987 | gimple ref_stmt; | |
1988 | int mask = LOOP_VINFO_PTR_MASK (loop_vinfo); | |
1989 | tree mask_cst; | |
1990 | unsigned int i; | |
fb85abff | 1991 | tree int_ptrsize_type; |
1992 | char tmp_name[20]; | |
1993 | tree or_tmp_name = NULL_TREE; | |
03d37e4e | 1994 | tree and_tmp_name; |
fb85abff | 1995 | gimple and_stmt; |
1996 | tree ptrsize_zero; | |
1997 | tree part_cond_expr; | |
1998 | ||
1999 | /* Check that mask is one less than a power of 2, i.e., mask is | |
2000 | all zeros followed by all ones. */ | |
2001 | gcc_assert ((mask != 0) && ((mask & (mask+1)) == 0)); | |
2002 | ||
3cea8318 | 2003 | int_ptrsize_type = signed_type_for (ptr_type_node); |
fb85abff | 2004 | |
2005 | /* Create expression (mask & (dr_1 || ... || dr_n)) where dr_i is the address | |
2006 | of the first vector of the i'th data reference. */ | |
2007 | ||
f1f41a6c | 2008 | FOR_EACH_VEC_ELT (may_misalign_stmts, i, ref_stmt) |
fb85abff | 2009 | { |
2010 | gimple_seq new_stmt_list = NULL; | |
2011 | tree addr_base; | |
03d37e4e | 2012 | tree addr_tmp_name; |
2013 | tree new_or_tmp_name; | |
fb85abff | 2014 | gimple addr_stmt, or_stmt; |
f1b8c740 | 2015 | stmt_vec_info stmt_vinfo = vinfo_for_stmt (ref_stmt); |
2016 | tree vectype = STMT_VINFO_VECTYPE (stmt_vinfo); | |
2017 | bool negative = tree_int_cst_compare | |
2018 | (DR_STEP (STMT_VINFO_DATA_REF (stmt_vinfo)), size_zero_node) < 0; | |
2019 | tree offset = negative | |
2020 | ? size_int (-TYPE_VECTOR_SUBPARTS (vectype) + 1) : NULL_TREE; | |
fb85abff | 2021 | |
2022 | /* create: addr_tmp = (int)(address_of_first_vector) */ | |
2023 | addr_base = | |
2024 | vect_create_addr_base_for_vector_ref (ref_stmt, &new_stmt_list, | |
f1b8c740 | 2025 | offset, loop); |
fb85abff | 2026 | if (new_stmt_list != NULL) |
2027 | gimple_seq_add_seq (cond_expr_stmt_list, new_stmt_list); | |
2028 | ||
03d37e4e | 2029 | sprintf (tmp_name, "addr2int%d", i); |
2030 | addr_tmp_name = make_temp_ssa_name (int_ptrsize_type, NULL, tmp_name); | |
fb85abff | 2031 | addr_stmt = gimple_build_assign_with_ops (NOP_EXPR, addr_tmp_name, |
2032 | addr_base, NULL_TREE); | |
fb85abff | 2033 | gimple_seq_add_stmt (cond_expr_stmt_list, addr_stmt); |
2034 | ||
2035 | /* The addresses are OR together. */ | |
2036 | ||
2037 | if (or_tmp_name != NULL_TREE) | |
2038 | { | |
2039 | /* create: or_tmp = or_tmp | addr_tmp */ | |
03d37e4e | 2040 | sprintf (tmp_name, "orptrs%d", i); |
2041 | new_or_tmp_name = make_temp_ssa_name (int_ptrsize_type, NULL, tmp_name); | |
fb85abff | 2042 | or_stmt = gimple_build_assign_with_ops (BIT_IOR_EXPR, |
2043 | new_or_tmp_name, | |
2044 | or_tmp_name, addr_tmp_name); | |
fb85abff | 2045 | gimple_seq_add_stmt (cond_expr_stmt_list, or_stmt); |
2046 | or_tmp_name = new_or_tmp_name; | |
2047 | } | |
2048 | else | |
2049 | or_tmp_name = addr_tmp_name; | |
2050 | ||
2051 | } /* end for i */ | |
2052 | ||
2053 | mask_cst = build_int_cst (int_ptrsize_type, mask); | |
2054 | ||
2055 | /* create: and_tmp = or_tmp & mask */ | |
03d37e4e | 2056 | and_tmp_name = make_temp_ssa_name (int_ptrsize_type, NULL, "andmask"); |
fb85abff | 2057 | |
2058 | and_stmt = gimple_build_assign_with_ops (BIT_AND_EXPR, and_tmp_name, | |
2059 | or_tmp_name, mask_cst); | |
fb85abff | 2060 | gimple_seq_add_stmt (cond_expr_stmt_list, and_stmt); |
2061 | ||
2062 | /* Make and_tmp the left operand of the conditional test against zero. | |
2063 | if and_tmp has a nonzero bit then some address is unaligned. */ | |
2064 | ptrsize_zero = build_int_cst (int_ptrsize_type, 0); | |
2065 | part_cond_expr = fold_build2 (EQ_EXPR, boolean_type_node, | |
2066 | and_tmp_name, ptrsize_zero); | |
2067 | if (*cond_expr) | |
2068 | *cond_expr = fold_build2 (TRUTH_AND_EXPR, boolean_type_node, | |
2069 | *cond_expr, part_cond_expr); | |
2070 | else | |
2071 | *cond_expr = part_cond_expr; | |
2072 | } | |
2073 | ||
fb85abff | 2074 | /* Function vect_create_cond_for_alias_checks. |
2075 | ||
2076 | Create a conditional expression that represents the run-time checks for | |
2077 | overlapping of address ranges represented by a list of data references | |
2078 | relations passed as input. | |
2079 | ||
2080 | Input: | |
2081 | COND_EXPR - input conditional expression. New conditions will be chained | |
8a7b0f48 | 2082 | with logical AND operation. If it is NULL, then the function |
2083 | is used to return the number of alias checks. | |
fb85abff | 2084 | LOOP_VINFO - field LOOP_VINFO_MAY_ALIAS_STMTS contains the list of ddrs |
2085 | to be checked. | |
2086 | ||
2087 | Output: | |
2088 | COND_EXPR - conditional expression. | |
fb85abff | 2089 | |
8a7b0f48 | 2090 | The returned COND_EXPR is the conditional expression to be used in the if |
fb85abff | 2091 | statement that controls which version of the loop gets executed at runtime. |
2092 | */ | |
2093 | ||
8a7b0f48 | 2094 | void |
90d4c4af | 2095 | vect_create_cond_for_alias_checks (loop_vec_info loop_vinfo, tree * cond_expr) |
fb85abff | 2096 | { |
43d14b66 | 2097 | vec<dr_with_seg_len_pair_t> comp_alias_ddrs = |
8a7b0f48 | 2098 | LOOP_VINFO_COMP_ALIAS_DDRS (loop_vinfo); |
2099 | tree part_cond_expr; | |
fb85abff | 2100 | |
2101 | /* Create expression | |
33767455 | 2102 | ((store_ptr_0 + store_segment_length_0) <= load_ptr_0) |
2103 | || (load_ptr_0 + load_segment_length_0) <= store_ptr_0)) | |
48e1416a | 2104 | && |
fb85abff | 2105 | ... |
2106 | && | |
33767455 | 2107 | ((store_ptr_n + store_segment_length_n) <= load_ptr_n) |
2108 | || (load_ptr_n + load_segment_length_n) <= store_ptr_n)) */ | |
fb85abff | 2109 | |
8a7b0f48 | 2110 | if (comp_alias_ddrs.is_empty ()) |
fb85abff | 2111 | return; |
2112 | ||
8a7b0f48 | 2113 | for (size_t i = 0, s = comp_alias_ddrs.length (); i < s; ++i) |
fb85abff | 2114 | { |
43d14b66 | 2115 | const dr_with_seg_len& dr_a = comp_alias_ddrs[i].first; |
2116 | const dr_with_seg_len& dr_b = comp_alias_ddrs[i].second; | |
8a7b0f48 | 2117 | tree segment_length_a = dr_a.seg_len; |
2118 | tree segment_length_b = dr_b.seg_len; | |
fb85abff | 2119 | |
8a7b0f48 | 2120 | tree addr_base_a |
43d14b66 | 2121 | = fold_build_pointer_plus (DR_BASE_ADDRESS (dr_a.dr), dr_a.offset); |
8a7b0f48 | 2122 | tree addr_base_b |
43d14b66 | 2123 | = fold_build_pointer_plus (DR_BASE_ADDRESS (dr_b.dr), dr_b.offset); |
fb85abff | 2124 | |
6d8fb6cf | 2125 | if (dump_enabled_p ()) |
fb85abff | 2126 | { |
b055bc88 | 2127 | dump_printf_loc (MSG_NOTE, vect_location, |
8a7b0f48 | 2128 | "create runtime check for data references "); |
2129 | dump_generic_expr (MSG_NOTE, TDF_SLIM, DR_REF (dr_a.dr)); | |
b055bc88 | 2130 | dump_printf (MSG_NOTE, " and "); |
8a7b0f48 | 2131 | dump_generic_expr (MSG_NOTE, TDF_SLIM, DR_REF (dr_b.dr)); |
2132 | dump_printf (MSG_NOTE, "\n"); | |
fb85abff | 2133 | } |
2134 | ||
8a7b0f48 | 2135 | tree seg_a_min = addr_base_a; |
2136 | tree seg_a_max = fold_build_pointer_plus (addr_base_a, segment_length_a); | |
2137 | if (tree_int_cst_compare (DR_STEP (dr_a.dr), size_zero_node) < 0) | |
f1b8c740 | 2138 | seg_a_min = seg_a_max, seg_a_max = addr_base_a; |
2139 | ||
8a7b0f48 | 2140 | tree seg_b_min = addr_base_b; |
2141 | tree seg_b_max = fold_build_pointer_plus (addr_base_b, segment_length_b); | |
2142 | if (tree_int_cst_compare (DR_STEP (dr_b.dr), size_zero_node) < 0) | |
f1b8c740 | 2143 | seg_b_min = seg_b_max, seg_b_max = addr_base_b; |
fb85abff | 2144 | |
48e1416a | 2145 | part_cond_expr = |
fb85abff | 2146 | fold_build2 (TRUTH_OR_EXPR, boolean_type_node, |
33767455 | 2147 | fold_build2 (LE_EXPR, boolean_type_node, seg_a_max, seg_b_min), |
2148 | fold_build2 (LE_EXPR, boolean_type_node, seg_b_max, seg_a_min)); | |
48e1416a | 2149 | |
fb85abff | 2150 | if (*cond_expr) |
2151 | *cond_expr = fold_build2 (TRUTH_AND_EXPR, boolean_type_node, | |
2152 | *cond_expr, part_cond_expr); | |
2153 | else | |
2154 | *cond_expr = part_cond_expr; | |
2155 | } | |
fb85abff | 2156 | |
6d8fb6cf | 2157 | if (dump_enabled_p ()) |
b055bc88 | 2158 | dump_printf_loc (MSG_NOTE, vect_location, |
7bd765d4 | 2159 | "created %u versioning for alias checks.\n", |
8a7b0f48 | 2160 | comp_alias_ddrs.length ()); |
2161 | ||
2162 | comp_alias_ddrs.release (); | |
fb85abff | 2163 | } |
2164 | ||
2165 | ||
2166 | /* Function vect_loop_versioning. | |
48e1416a | 2167 | |
fb85abff | 2168 | If the loop has data references that may or may not be aligned or/and |
2169 | has data reference relations whose independence was not proven then | |
2170 | two versions of the loop need to be generated, one which is vectorized | |
2171 | and one which isn't. A test is then generated to control which of the | |
2172 | loops is executed. The test checks for the alignment of all of the | |
2173 | data references that may or may not be aligned. An additional | |
2174 | sequence of runtime tests is generated for each pairs of DDRs whose | |
48e1416a | 2175 | independence was not proven. The vectorized version of loop is |
2176 | executed only if both alias and alignment tests are passed. | |
2177 | ||
fb85abff | 2178 | The test generated to check which version of loop is executed |
48e1416a | 2179 | is modified to also check for profitability as indicated by the |
23a3430d | 2180 | cost model initially. |
2181 | ||
2182 | The versioning precondition(s) are placed in *COND_EXPR and | |
2afdcbed | 2183 | *COND_EXPR_STMT_LIST. */ |
fb85abff | 2184 | |
2185 | void | |
e7430948 | 2186 | vect_loop_versioning (loop_vec_info loop_vinfo, |
2187 | unsigned int th, bool check_profitability) | |
fb85abff | 2188 | { |
2189 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); | |
fb85abff | 2190 | basic_block condition_bb; |
2191 | gimple_stmt_iterator gsi, cond_exp_gsi; | |
2192 | basic_block merge_bb; | |
2193 | basic_block new_exit_bb; | |
2194 | edge new_exit_e, e; | |
2195 | gimple orig_phi, new_phi; | |
e7430948 | 2196 | tree cond_expr = NULL_TREE; |
2afdcbed | 2197 | gimple_seq cond_expr_stmt_list = NULL; |
fb85abff | 2198 | tree arg; |
2199 | unsigned prob = 4 * REG_BR_PROB_BASE / 5; | |
2200 | gimple_seq gimplify_stmt_list = NULL; | |
2201 | tree scalar_loop_iters = LOOP_VINFO_NITERS (loop_vinfo); | |
6ee2edad | 2202 | bool version_align = LOOP_REQUIRES_VERSIONING_FOR_ALIGNMENT (loop_vinfo); |
2203 | bool version_alias = LOOP_REQUIRES_VERSIONING_FOR_ALIAS (loop_vinfo); | |
fb85abff | 2204 | |
e7430948 | 2205 | if (check_profitability) |
2206 | { | |
2207 | cond_expr = fold_build2 (GT_EXPR, boolean_type_node, scalar_loop_iters, | |
2208 | build_int_cst (TREE_TYPE (scalar_loop_iters), th)); | |
2209 | cond_expr = force_gimple_operand_1 (cond_expr, &cond_expr_stmt_list, | |
2210 | is_gimple_condexpr, NULL_TREE); | |
2211 | } | |
fb85abff | 2212 | |
6ee2edad | 2213 | if (version_align) |
2afdcbed | 2214 | vect_create_cond_for_align_checks (loop_vinfo, &cond_expr, |
2215 | &cond_expr_stmt_list); | |
fb85abff | 2216 | |
6ee2edad | 2217 | if (version_alias) |
90d4c4af | 2218 | vect_create_cond_for_alias_checks (loop_vinfo, &cond_expr); |
23a3430d | 2219 | |
2afdcbed | 2220 | cond_expr = force_gimple_operand_1 (cond_expr, &gimplify_stmt_list, |
2221 | is_gimple_condexpr, NULL_TREE); | |
2222 | gimple_seq_add_seq (&cond_expr_stmt_list, gimplify_stmt_list); | |
fb85abff | 2223 | |
2224 | initialize_original_copy_tables (); | |
2afdcbed | 2225 | loop_version (loop, cond_expr, &condition_bb, |
f018d957 | 2226 | prob, prob, REG_BR_PROB_BASE - prob, true); |
6ee2edad | 2227 | |
36f39b2e | 2228 | if (LOCATION_LOCUS (vect_location) != UNKNOWN_LOCATION |
6ee2edad | 2229 | && dump_enabled_p ()) |
2230 | { | |
2231 | if (version_alias) | |
2232 | dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, vect_location, | |
2233 | "loop versioned for vectorization because of " | |
2234 | "possible aliasing\n"); | |
2235 | if (version_align) | |
2236 | dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, vect_location, | |
2237 | "loop versioned for vectorization to enhance " | |
2238 | "alignment\n"); | |
2239 | ||
2240 | } | |
9af5ce0c | 2241 | free_original_copy_tables (); |
fb85abff | 2242 | |
48e1416a | 2243 | /* Loop versioning violates an assumption we try to maintain during |
fb85abff | 2244 | vectorization - that the loop exit block has a single predecessor. |
2245 | After versioning, the exit block of both loop versions is the same | |
2246 | basic block (i.e. it has two predecessors). Just in order to simplify | |
2247 | following transformations in the vectorizer, we fix this situation | |
2248 | here by adding a new (empty) block on the exit-edge of the loop, | |
2249 | with the proper loop-exit phis to maintain loop-closed-form. */ | |
48e1416a | 2250 | |
fb85abff | 2251 | merge_bb = single_exit (loop)->dest; |
2252 | gcc_assert (EDGE_COUNT (merge_bb->preds) == 2); | |
2253 | new_exit_bb = split_edge (single_exit (loop)); | |
2254 | new_exit_e = single_exit (loop); | |
2255 | e = EDGE_SUCC (new_exit_bb, 0); | |
2256 | ||
2257 | for (gsi = gsi_start_phis (merge_bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
2258 | { | |
874117c8 | 2259 | tree new_res; |
fb85abff | 2260 | orig_phi = gsi_stmt (gsi); |
874117c8 | 2261 | new_res = copy_ssa_name (PHI_RESULT (orig_phi), NULL); |
2262 | new_phi = create_phi_node (new_res, new_exit_bb); | |
fb85abff | 2263 | arg = PHI_ARG_DEF_FROM_EDGE (orig_phi, e); |
48e1416a | 2264 | add_phi_arg (new_phi, arg, new_exit_e, |
60d535d2 | 2265 | gimple_phi_arg_location_from_edge (orig_phi, e)); |
b123eaab | 2266 | adjust_phi_and_debug_stmts (orig_phi, e, PHI_RESULT (new_phi)); |
48e1416a | 2267 | } |
fb85abff | 2268 | |
c7b85126 | 2269 | |
2270 | /* Extract load statements on memrefs with zero-stride accesses. */ | |
2271 | ||
2272 | if (LOOP_REQUIRES_VERSIONING_FOR_ALIAS (loop_vinfo)) | |
2273 | { | |
2274 | /* In the loop body, we iterate each statement to check if it is a load. | |
2275 | Then we check the DR_STEP of the data reference. If DR_STEP is zero, | |
2276 | then we will hoist the load statement to the loop preheader. */ | |
2277 | ||
2278 | basic_block *bbs = LOOP_VINFO_BBS (loop_vinfo); | |
2279 | int nbbs = loop->num_nodes; | |
2280 | ||
2281 | for (int i = 0; i < nbbs; ++i) | |
2282 | { | |
2283 | for (gimple_stmt_iterator si = gsi_start_bb (bbs[i]); | |
2284 | !gsi_end_p (si);) | |
2285 | { | |
2286 | gimple stmt = gsi_stmt (si); | |
2287 | stmt_vec_info stmt_info = vinfo_for_stmt (stmt); | |
2288 | struct data_reference *dr = STMT_VINFO_DATA_REF (stmt_info); | |
2289 | ||
2290 | if (is_gimple_assign (stmt) | |
2291 | && (!dr | |
2292 | || (DR_IS_READ (dr) && integer_zerop (DR_STEP (dr))))) | |
2293 | { | |
2294 | bool hoist = true; | |
2295 | ssa_op_iter iter; | |
2296 | tree var; | |
2297 | ||
2298 | /* We hoist a statement if all SSA uses in it are defined | |
2299 | outside of the loop. */ | |
2300 | FOR_EACH_SSA_TREE_OPERAND (var, stmt, iter, SSA_OP_USE) | |
2301 | { | |
2302 | gimple def = SSA_NAME_DEF_STMT (var); | |
2303 | if (!gimple_nop_p (def) | |
2304 | && flow_bb_inside_loop_p (loop, gimple_bb (def))) | |
2305 | { | |
2306 | hoist = false; | |
2307 | break; | |
2308 | } | |
2309 | } | |
2310 | ||
2311 | if (hoist) | |
2312 | { | |
2313 | if (dr) | |
2314 | gimple_set_vuse (stmt, NULL); | |
2315 | ||
2316 | gsi_remove (&si, false); | |
2317 | gsi_insert_on_edge_immediate (loop_preheader_edge (loop), | |
2318 | stmt); | |
2319 | ||
2320 | if (dump_enabled_p ()) | |
2321 | { | |
2322 | dump_printf_loc | |
2323 | (MSG_NOTE, vect_location, | |
2324 | "hoisting out of the vectorized loop: "); | |
2325 | dump_gimple_stmt (MSG_NOTE, TDF_SLIM, stmt, 0); | |
2326 | dump_printf (MSG_NOTE, "\n"); | |
2327 | } | |
2328 | continue; | |
2329 | } | |
2330 | } | |
2331 | gsi_next (&si); | |
2332 | } | |
2333 | } | |
2334 | } | |
2335 | ||
fb85abff | 2336 | /* End loop-exit-fixes after versioning. */ |
2337 | ||
2afdcbed | 2338 | if (cond_expr_stmt_list) |
fb85abff | 2339 | { |
2340 | cond_exp_gsi = gsi_last_bb (condition_bb); | |
2afdcbed | 2341 | gsi_insert_seq_before (&cond_exp_gsi, cond_expr_stmt_list, |
23a3430d | 2342 | GSI_SAME_STMT); |
fb85abff | 2343 | } |
95e19962 | 2344 | update_ssa (TODO_update_ssa); |
fb85abff | 2345 | } |