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48e1416a | 1 | /* Vectorizer Specific Loop Manipulations |
aad93da1 | 2 | Copyright (C) 2003-2017 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" | |
9ef16211 | 25 | #include "backend.h" |
b20a8bb4 | 26 | #include "tree.h" |
9ef16211 | 27 | #include "gimple.h" |
7c29e30e | 28 | #include "cfghooks.h" |
29 | #include "tree-pass.h" | |
9ef16211 | 30 | #include "ssa.h" |
9ef16211 | 31 | #include "fold-const.h" |
94ea8568 | 32 | #include "cfganal.h" |
a8783bee | 33 | #include "gimplify.h" |
dcf1a1ec | 34 | #include "gimple-iterator.h" |
e795d6e1 | 35 | #include "gimplify-me.h" |
073c1fd5 | 36 | #include "tree-cfg.h" |
05d9c18a | 37 | #include "tree-ssa-loop-manip.h" |
073c1fd5 | 38 | #include "tree-into-ssa.h" |
69ee5dbb | 39 | #include "tree-ssa.h" |
fb85abff | 40 | #include "cfgloop.h" |
fb85abff | 41 | #include "tree-scalar-evolution.h" |
42 | #include "tree-vectorizer.h" | |
12117f39 | 43 | #include "tree-ssa-loop-ivopts.h" |
fb85abff | 44 | |
45 | /************************************************************************* | |
46 | Simple Loop Peeling Utilities | |
47 | ||
48 | Utilities to support loop peeling for vectorization purposes. | |
49 | *************************************************************************/ | |
50 | ||
51 | ||
52 | /* Renames the use *OP_P. */ | |
53 | ||
54 | static void | |
55 | rename_use_op (use_operand_p op_p) | |
56 | { | |
57 | tree new_name; | |
58 | ||
59 | if (TREE_CODE (USE_FROM_PTR (op_p)) != SSA_NAME) | |
60 | return; | |
61 | ||
62 | new_name = get_current_def (USE_FROM_PTR (op_p)); | |
63 | ||
64 | /* Something defined outside of the loop. */ | |
65 | if (!new_name) | |
66 | return; | |
67 | ||
68 | /* An ordinary ssa name defined in the loop. */ | |
69 | ||
70 | SET_USE (op_p, new_name); | |
71 | } | |
72 | ||
73 | ||
ccd0a9f9 | 74 | /* Renames the variables in basic block BB. Allow renaming of PHI arguments |
5ee742c4 | 75 | on edges incoming from outer-block header if RENAME_FROM_OUTER_LOOP is |
76 | true. */ | |
fb85abff | 77 | |
c9b2c569 | 78 | static void |
5ee742c4 | 79 | rename_variables_in_bb (basic_block bb, bool rename_from_outer_loop) |
fb85abff | 80 | { |
42acab1c | 81 | gimple *stmt; |
fb85abff | 82 | use_operand_p use_p; |
83 | ssa_op_iter iter; | |
84 | edge e; | |
85 | edge_iterator ei; | |
86 | struct loop *loop = bb->loop_father; | |
5ee742c4 | 87 | struct loop *outer_loop = NULL; |
88 | ||
89 | if (rename_from_outer_loop) | |
90 | { | |
91 | gcc_assert (loop); | |
92 | outer_loop = loop_outer (loop); | |
93 | } | |
fb85abff | 94 | |
1a91d914 | 95 | for (gimple_stmt_iterator gsi = gsi_start_bb (bb); !gsi_end_p (gsi); |
96 | gsi_next (&gsi)) | |
fb85abff | 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 | { |
ccd0a9f9 | 105 | if (!flow_bb_inside_loop_p (loop, e->src)) |
106 | { | |
107 | if (!rename_from_outer_loop) | |
108 | continue; | |
109 | if (e->src != outer_loop->header) | |
110 | { | |
111 | if (outer_loop->inner->next) | |
112 | { | |
113 | /* If outer_loop has 2 inner loops, allow there to | |
114 | be an extra basic block which decides which of the | |
115 | two loops to use using LOOP_VECTORIZED. */ | |
116 | if (!single_pred_p (e->src) | |
117 | || single_pred (e->src) != outer_loop->header) | |
118 | continue; | |
119 | } | |
ccd0a9f9 | 120 | } |
121 | } | |
1a91d914 | 122 | for (gphi_iterator gsi = gsi_start_phis (bb); !gsi_end_p (gsi); |
123 | gsi_next (&gsi)) | |
124 | rename_use_op (PHI_ARG_DEF_PTR_FROM_EDGE (gsi.phi (), e)); | |
fb85abff | 125 | } |
126 | } | |
127 | ||
128 | ||
6dc50383 | 129 | struct adjust_info |
b123eaab | 130 | { |
131 | tree from, to; | |
132 | basic_block bb; | |
6dc50383 | 133 | }; |
b123eaab | 134 | |
b123eaab | 135 | /* A stack of values to be adjusted in debug stmts. We have to |
136 | process them LIFO, so that the closest substitution applies. If we | |
137 | processed them FIFO, without the stack, we might substitute uses | |
138 | with a PHI DEF that would soon become non-dominant, and when we got | |
139 | to the suitable one, it wouldn't have anything to substitute any | |
140 | more. */ | |
d70aebca | 141 | static vec<adjust_info, va_heap> adjust_vec; |
b123eaab | 142 | |
143 | /* Adjust any debug stmts that referenced AI->from values to use the | |
144 | loop-closed AI->to, if the references are dominated by AI->bb and | |
145 | not by the definition of AI->from. */ | |
146 | ||
147 | static void | |
148 | adjust_debug_stmts_now (adjust_info *ai) | |
149 | { | |
150 | basic_block bbphi = ai->bb; | |
151 | tree orig_def = ai->from; | |
152 | tree new_def = ai->to; | |
153 | imm_use_iterator imm_iter; | |
42acab1c | 154 | gimple *stmt; |
b123eaab | 155 | basic_block bbdef = gimple_bb (SSA_NAME_DEF_STMT (orig_def)); |
156 | ||
157 | gcc_assert (dom_info_available_p (CDI_DOMINATORS)); | |
158 | ||
159 | /* Adjust any debug stmts that held onto non-loop-closed | |
160 | references. */ | |
161 | FOR_EACH_IMM_USE_STMT (stmt, imm_iter, orig_def) | |
162 | { | |
163 | use_operand_p use_p; | |
164 | basic_block bbuse; | |
165 | ||
166 | if (!is_gimple_debug (stmt)) | |
167 | continue; | |
168 | ||
169 | gcc_assert (gimple_debug_bind_p (stmt)); | |
170 | ||
171 | bbuse = gimple_bb (stmt); | |
172 | ||
173 | if ((bbuse == bbphi | |
174 | || dominated_by_p (CDI_DOMINATORS, bbuse, bbphi)) | |
175 | && !(bbuse == bbdef | |
176 | || dominated_by_p (CDI_DOMINATORS, bbuse, bbdef))) | |
177 | { | |
178 | if (new_def) | |
179 | FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter) | |
180 | SET_USE (use_p, new_def); | |
181 | else | |
182 | { | |
183 | gimple_debug_bind_reset_value (stmt); | |
184 | update_stmt (stmt); | |
185 | } | |
186 | } | |
187 | } | |
188 | } | |
189 | ||
190 | /* Adjust debug stmts as scheduled before. */ | |
191 | ||
192 | static void | |
193 | adjust_vec_debug_stmts (void) | |
194 | { | |
195 | if (!MAY_HAVE_DEBUG_STMTS) | |
196 | return; | |
197 | ||
f1f41a6c | 198 | gcc_assert (adjust_vec.exists ()); |
b123eaab | 199 | |
f1f41a6c | 200 | while (!adjust_vec.is_empty ()) |
b123eaab | 201 | { |
f1f41a6c | 202 | adjust_debug_stmts_now (&adjust_vec.last ()); |
203 | adjust_vec.pop (); | |
b123eaab | 204 | } |
b123eaab | 205 | } |
206 | ||
207 | /* Adjust any debug stmts that referenced FROM values to use the | |
208 | loop-closed TO, if the references are dominated by BB and not by | |
209 | the definition of FROM. If adjust_vec is non-NULL, adjustments | |
210 | will be postponed until adjust_vec_debug_stmts is called. */ | |
211 | ||
212 | static void | |
213 | adjust_debug_stmts (tree from, tree to, basic_block bb) | |
214 | { | |
215 | adjust_info ai; | |
216 | ||
0087edc6 | 217 | if (MAY_HAVE_DEBUG_STMTS |
218 | && TREE_CODE (from) == SSA_NAME | |
2510e5cd | 219 | && ! SSA_NAME_IS_DEFAULT_DEF (from) |
0087edc6 | 220 | && ! virtual_operand_p (from)) |
b123eaab | 221 | { |
222 | ai.from = from; | |
223 | ai.to = to; | |
224 | ai.bb = bb; | |
225 | ||
f1f41a6c | 226 | if (adjust_vec.exists ()) |
227 | adjust_vec.safe_push (ai); | |
b123eaab | 228 | else |
229 | adjust_debug_stmts_now (&ai); | |
230 | } | |
231 | } | |
232 | ||
233 | /* Change E's phi arg in UPDATE_PHI to NEW_DEF, and record information | |
234 | to adjust any debug stmts that referenced the old phi arg, | |
235 | presumably non-loop-closed references left over from other | |
236 | transformations. */ | |
237 | ||
238 | static void | |
42acab1c | 239 | adjust_phi_and_debug_stmts (gimple *update_phi, edge e, tree new_def) |
b123eaab | 240 | { |
241 | tree orig_def = PHI_ARG_DEF_FROM_EDGE (update_phi, e); | |
242 | ||
243 | SET_PHI_ARG_DEF (update_phi, e->dest_idx, new_def); | |
244 | ||
245 | if (MAY_HAVE_DEBUG_STMTS) | |
246 | adjust_debug_stmts (orig_def, PHI_RESULT (update_phi), | |
247 | gimple_bb (update_phi)); | |
248 | } | |
249 | ||
fb85abff | 250 | /* Make the LOOP iterate NITERS times. This is done by adding a new IV |
251 | that starts at zero, increases by one and its limit is NITERS. | |
252 | ||
253 | Assumption: the exit-condition of LOOP is the last stmt in the loop. */ | |
254 | ||
255 | void | |
256 | slpeel_make_loop_iterate_ntimes (struct loop *loop, tree niters) | |
257 | { | |
258 | tree indx_before_incr, indx_after_incr; | |
1a91d914 | 259 | gcond *cond_stmt; |
260 | gcond *orig_cond; | |
fb85abff | 261 | edge exit_edge = single_exit (loop); |
262 | gimple_stmt_iterator loop_cond_gsi; | |
263 | gimple_stmt_iterator incr_gsi; | |
264 | bool insert_after; | |
265 | tree init = build_int_cst (TREE_TYPE (niters), 0); | |
266 | tree step = build_int_cst (TREE_TYPE (niters), 1); | |
36f39b2e | 267 | source_location loop_loc; |
fb85abff | 268 | enum tree_code code; |
269 | ||
270 | orig_cond = get_loop_exit_condition (loop); | |
271 | gcc_assert (orig_cond); | |
272 | loop_cond_gsi = gsi_for_stmt (orig_cond); | |
273 | ||
274 | standard_iv_increment_position (loop, &incr_gsi, &insert_after); | |
275 | create_iv (init, step, NULL_TREE, loop, | |
276 | &incr_gsi, insert_after, &indx_before_incr, &indx_after_incr); | |
277 | ||
278 | indx_after_incr = force_gimple_operand_gsi (&loop_cond_gsi, indx_after_incr, | |
279 | true, NULL_TREE, true, | |
280 | GSI_SAME_STMT); | |
281 | niters = force_gimple_operand_gsi (&loop_cond_gsi, niters, true, NULL_TREE, | |
282 | true, GSI_SAME_STMT); | |
283 | ||
284 | code = (exit_edge->flags & EDGE_TRUE_VALUE) ? GE_EXPR : LT_EXPR; | |
285 | cond_stmt = gimple_build_cond (code, indx_after_incr, niters, NULL_TREE, | |
286 | NULL_TREE); | |
287 | ||
288 | gsi_insert_before (&loop_cond_gsi, cond_stmt, GSI_SAME_STMT); | |
289 | ||
290 | /* Remove old loop exit test: */ | |
291 | gsi_remove (&loop_cond_gsi, true); | |
706567b8 | 292 | free_stmt_vec_info (orig_cond); |
fb85abff | 293 | |
294 | loop_loc = find_loop_location (loop); | |
6d8fb6cf | 295 | if (dump_enabled_p ()) |
fb85abff | 296 | { |
36f39b2e | 297 | if (LOCATION_LOCUS (loop_loc) != UNKNOWN_LOCATION) |
298 | dump_printf (MSG_NOTE, "\nloop at %s:%d: ", LOCATION_FILE (loop_loc), | |
299 | LOCATION_LINE (loop_loc)); | |
7bd765d4 | 300 | dump_gimple_stmt (MSG_NOTE, TDF_SLIM, cond_stmt, 0); |
fb85abff | 301 | } |
56c0f85a | 302 | |
303 | /* Record the number of latch iterations. */ | |
304 | loop->nb_iterations = fold_build2 (MINUS_EXPR, TREE_TYPE (niters), niters, | |
305 | build_int_cst (TREE_TYPE (niters), 1)); | |
fb85abff | 306 | } |
307 | ||
c71d3c24 | 308 | /* Helper routine of slpeel_tree_duplicate_loop_to_edge_cfg. |
309 | For all PHI arguments in FROM->dest and TO->dest from those | |
310 | edges ensure that TO->dest PHI arguments have current_def | |
311 | to that in from. */ | |
312 | ||
313 | static void | |
314 | slpeel_duplicate_current_defs_from_edges (edge from, edge to) | |
315 | { | |
316 | gimple_stmt_iterator gsi_from, gsi_to; | |
317 | ||
318 | for (gsi_from = gsi_start_phis (from->dest), | |
319 | gsi_to = gsi_start_phis (to->dest); | |
e87502d6 | 320 | !gsi_end_p (gsi_from) && !gsi_end_p (gsi_to);) |
c71d3c24 | 321 | { |
42acab1c | 322 | gimple *from_phi = gsi_stmt (gsi_from); |
323 | gimple *to_phi = gsi_stmt (gsi_to); | |
c71d3c24 | 324 | tree from_arg = PHI_ARG_DEF_FROM_EDGE (from_phi, from); |
e3243c77 | 325 | tree to_arg = PHI_ARG_DEF_FROM_EDGE (to_phi, to); |
326 | if (virtual_operand_p (from_arg)) | |
327 | { | |
e87502d6 | 328 | gsi_next (&gsi_from); |
329 | continue; | |
330 | } | |
e3243c77 | 331 | if (virtual_operand_p (to_arg)) |
332 | { | |
e87502d6 | 333 | gsi_next (&gsi_to); |
334 | continue; | |
335 | } | |
e3243c77 | 336 | if (TREE_CODE (from_arg) != SSA_NAME) |
337 | gcc_assert (operand_equal_p (from_arg, to_arg, 0)); | |
338 | else | |
339 | { | |
340 | if (get_current_def (to_arg) == NULL_TREE) | |
341 | set_current_def (to_arg, get_current_def (from_arg)); | |
342 | } | |
e87502d6 | 343 | gsi_next (&gsi_from); |
344 | gsi_next (&gsi_to); | |
c71d3c24 | 345 | } |
e3243c77 | 346 | |
347 | gphi *from_phi = get_virtual_phi (from->dest); | |
348 | gphi *to_phi = get_virtual_phi (to->dest); | |
349 | if (from_phi) | |
350 | set_current_def (PHI_ARG_DEF_FROM_EDGE (to_phi, to), | |
351 | get_current_def (PHI_ARG_DEF_FROM_EDGE (from_phi, from))); | |
c71d3c24 | 352 | } |
353 | ||
fb85abff | 354 | |
48e1416a | 355 | /* Given LOOP this function generates a new copy of it and puts it |
c71d3c24 | 356 | on E which is either the entry or exit of LOOP. If SCALAR_LOOP is |
357 | non-NULL, assume LOOP and SCALAR_LOOP are equivalent and copy the | |
358 | basic blocks from SCALAR_LOOP instead of LOOP, but to either the | |
359 | entry or exit of LOOP. */ | |
fb85abff | 360 | |
361 | struct loop * | |
c71d3c24 | 362 | slpeel_tree_duplicate_loop_to_edge_cfg (struct loop *loop, |
363 | struct loop *scalar_loop, edge e) | |
fb85abff | 364 | { |
365 | struct loop *new_loop; | |
8a61cfb8 | 366 | basic_block *new_bbs, *bbs, *pbbs; |
fb85abff | 367 | bool at_exit; |
368 | bool was_imm_dom; | |
48e1416a | 369 | basic_block exit_dest; |
fb85abff | 370 | edge exit, new_exit; |
5ee742c4 | 371 | bool duplicate_outer_loop = false; |
fb85abff | 372 | |
c9b2c569 | 373 | exit = single_exit (loop); |
374 | at_exit = (e == exit); | |
fb85abff | 375 | if (!at_exit && e != loop_preheader_edge (loop)) |
376 | return NULL; | |
377 | ||
c71d3c24 | 378 | if (scalar_loop == NULL) |
379 | scalar_loop = loop; | |
380 | ||
381 | bbs = XNEWVEC (basic_block, scalar_loop->num_nodes + 1); | |
8a61cfb8 | 382 | pbbs = bbs + 1; |
383 | get_loop_body_with_size (scalar_loop, pbbs, scalar_loop->num_nodes); | |
5ee742c4 | 384 | /* Allow duplication of outer loops. */ |
385 | if (scalar_loop->inner) | |
386 | duplicate_outer_loop = true; | |
fb85abff | 387 | /* Check whether duplication is possible. */ |
8a61cfb8 | 388 | if (!can_copy_bbs_p (pbbs, scalar_loop->num_nodes)) |
fb85abff | 389 | { |
390 | free (bbs); | |
391 | return NULL; | |
392 | } | |
393 | ||
394 | /* Generate new loop structure. */ | |
c71d3c24 | 395 | new_loop = duplicate_loop (scalar_loop, loop_outer (scalar_loop)); |
396 | duplicate_subloops (scalar_loop, new_loop); | |
fb85abff | 397 | |
c9b2c569 | 398 | exit_dest = exit->dest; |
48e1416a | 399 | was_imm_dom = (get_immediate_dominator (CDI_DOMINATORS, |
400 | exit_dest) == loop->header ? | |
fb85abff | 401 | true : false); |
402 | ||
c9b2c569 | 403 | /* Also copy the pre-header, this avoids jumping through hoops to |
404 | duplicate the loop entry PHI arguments. Create an empty | |
405 | pre-header unconditionally for this. */ | |
c71d3c24 | 406 | basic_block preheader = split_edge (loop_preheader_edge (scalar_loop)); |
c9b2c569 | 407 | edge entry_e = single_pred_edge (preheader); |
8a61cfb8 | 408 | bbs[0] = preheader; |
c71d3c24 | 409 | new_bbs = XNEWVEC (basic_block, scalar_loop->num_nodes + 1); |
fb85abff | 410 | |
c71d3c24 | 411 | exit = single_exit (scalar_loop); |
412 | copy_bbs (bbs, scalar_loop->num_nodes + 1, new_bbs, | |
fb85abff | 413 | &exit, 1, &new_exit, NULL, |
8a61cfb8 | 414 | at_exit ? loop->latch : e->src, true); |
c71d3c24 | 415 | exit = single_exit (loop); |
8a61cfb8 | 416 | basic_block new_preheader = new_bbs[0]; |
fb85abff | 417 | |
c71d3c24 | 418 | add_phi_args_after_copy (new_bbs, scalar_loop->num_nodes + 1, NULL); |
fb85abff | 419 | |
c71d3c24 | 420 | if (scalar_loop != loop) |
421 | { | |
422 | /* If we copied from SCALAR_LOOP rather than LOOP, SSA_NAMEs from | |
423 | SCALAR_LOOP will have current_def set to SSA_NAMEs in the new_loop, | |
424 | but LOOP will not. slpeel_update_phi_nodes_for_guard{1,2} expects | |
425 | the LOOP SSA_NAMEs (on the exit edge and edge from latch to | |
426 | header) to have current_def set, so copy them over. */ | |
427 | slpeel_duplicate_current_defs_from_edges (single_exit (scalar_loop), | |
428 | exit); | |
429 | slpeel_duplicate_current_defs_from_edges (EDGE_SUCC (scalar_loop->latch, | |
430 | 0), | |
431 | EDGE_SUCC (loop->latch, 0)); | |
432 | } | |
48e1416a | 433 | |
fb85abff | 434 | if (at_exit) /* Add the loop copy at exit. */ |
435 | { | |
c71d3c24 | 436 | if (scalar_loop != loop) |
437 | { | |
1a91d914 | 438 | gphi_iterator gsi; |
c71d3c24 | 439 | new_exit = redirect_edge_and_branch (new_exit, exit_dest); |
440 | ||
441 | for (gsi = gsi_start_phis (exit_dest); !gsi_end_p (gsi); | |
442 | gsi_next (&gsi)) | |
443 | { | |
1a91d914 | 444 | gphi *phi = gsi.phi (); |
c71d3c24 | 445 | tree orig_arg = PHI_ARG_DEF_FROM_EDGE (phi, e); |
446 | location_t orig_locus | |
447 | = gimple_phi_arg_location_from_edge (phi, e); | |
448 | ||
449 | add_phi_arg (phi, orig_arg, new_exit, orig_locus); | |
450 | } | |
451 | } | |
c9b2c569 | 452 | redirect_edge_and_branch_force (e, new_preheader); |
453 | flush_pending_stmts (e); | |
454 | set_immediate_dominator (CDI_DOMINATORS, new_preheader, e->src); | |
5ee742c4 | 455 | if (was_imm_dom || duplicate_outer_loop) |
c71d3c24 | 456 | set_immediate_dominator (CDI_DOMINATORS, exit_dest, new_exit->src); |
c9b2c569 | 457 | |
458 | /* And remove the non-necessary forwarder again. Keep the other | |
459 | one so we have a proper pre-header for the loop at the exit edge. */ | |
c71d3c24 | 460 | redirect_edge_pred (single_succ_edge (preheader), |
461 | single_pred (preheader)); | |
c9b2c569 | 462 | delete_basic_block (preheader); |
c71d3c24 | 463 | set_immediate_dominator (CDI_DOMINATORS, scalar_loop->header, |
464 | loop_preheader_edge (scalar_loop)->src); | |
fb85abff | 465 | } |
466 | else /* Add the copy at entry. */ | |
467 | { | |
c71d3c24 | 468 | if (scalar_loop != loop) |
469 | { | |
470 | /* Remove the non-necessary forwarder of scalar_loop again. */ | |
471 | redirect_edge_pred (single_succ_edge (preheader), | |
472 | single_pred (preheader)); | |
473 | delete_basic_block (preheader); | |
474 | set_immediate_dominator (CDI_DOMINATORS, scalar_loop->header, | |
475 | loop_preheader_edge (scalar_loop)->src); | |
476 | preheader = split_edge (loop_preheader_edge (loop)); | |
477 | entry_e = single_pred_edge (preheader); | |
478 | } | |
479 | ||
c9b2c569 | 480 | redirect_edge_and_branch_force (entry_e, new_preheader); |
481 | flush_pending_stmts (entry_e); | |
482 | set_immediate_dominator (CDI_DOMINATORS, new_preheader, entry_e->src); | |
483 | ||
484 | redirect_edge_and_branch_force (new_exit, preheader); | |
485 | flush_pending_stmts (new_exit); | |
486 | set_immediate_dominator (CDI_DOMINATORS, preheader, new_exit->src); | |
487 | ||
488 | /* And remove the non-necessary forwarder again. Keep the other | |
489 | one so we have a proper pre-header for the loop at the exit edge. */ | |
c71d3c24 | 490 | redirect_edge_pred (single_succ_edge (new_preheader), |
491 | single_pred (new_preheader)); | |
c9b2c569 | 492 | delete_basic_block (new_preheader); |
493 | set_immediate_dominator (CDI_DOMINATORS, new_loop->header, | |
494 | loop_preheader_edge (new_loop)->src); | |
fb85abff | 495 | } |
496 | ||
6e429c5c | 497 | /* Skip new preheader since it's deleted if copy loop is added at entry. */ |
498 | for (unsigned i = (at_exit ? 0 : 1); i < scalar_loop->num_nodes + 1; i++) | |
5ee742c4 | 499 | rename_variables_in_bb (new_bbs[i], duplicate_outer_loop); |
c9b2c569 | 500 | |
c71d3c24 | 501 | if (scalar_loop != loop) |
502 | { | |
503 | /* Update new_loop->header PHIs, so that on the preheader | |
504 | edge they are the ones from loop rather than scalar_loop. */ | |
1a91d914 | 505 | gphi_iterator gsi_orig, gsi_new; |
c71d3c24 | 506 | edge orig_e = loop_preheader_edge (loop); |
507 | edge new_e = loop_preheader_edge (new_loop); | |
508 | ||
509 | for (gsi_orig = gsi_start_phis (loop->header), | |
510 | gsi_new = gsi_start_phis (new_loop->header); | |
511 | !gsi_end_p (gsi_orig) && !gsi_end_p (gsi_new); | |
512 | gsi_next (&gsi_orig), gsi_next (&gsi_new)) | |
513 | { | |
1a91d914 | 514 | gphi *orig_phi = gsi_orig.phi (); |
515 | gphi *new_phi = gsi_new.phi (); | |
c71d3c24 | 516 | tree orig_arg = PHI_ARG_DEF_FROM_EDGE (orig_phi, orig_e); |
517 | location_t orig_locus | |
518 | = gimple_phi_arg_location_from_edge (orig_phi, orig_e); | |
519 | ||
520 | add_phi_arg (new_phi, orig_arg, new_e, orig_locus); | |
521 | } | |
522 | } | |
523 | ||
fb85abff | 524 | free (new_bbs); |
525 | free (bbs); | |
526 | ||
382ecba7 | 527 | checking_verify_dominators (CDI_DOMINATORS); |
c9b2c569 | 528 | |
fb85abff | 529 | return new_loop; |
530 | } | |
531 | ||
532 | ||
6c6a3430 | 533 | /* Given the condition expression COND, put it as the last statement of |
534 | GUARD_BB; set both edges' probability; set dominator of GUARD_TO to | |
535 | DOM_BB; return the skip edge. GUARD_TO is the target basic block to | |
15492f79 | 536 | skip the loop. PROBABILITY is the skip edge's probability. Mark the |
537 | new edge as irreducible if IRREDUCIBLE_P is true. */ | |
fb85abff | 538 | |
539 | static edge | |
23a3430d | 540 | slpeel_add_loop_guard (basic_block guard_bb, tree cond, |
6c6a3430 | 541 | basic_block guard_to, basic_block dom_bb, |
720cfc43 | 542 | profile_probability probability, bool irreducible_p) |
fb85abff | 543 | { |
544 | gimple_stmt_iterator gsi; | |
545 | edge new_e, enter_e; | |
1a91d914 | 546 | gcond *cond_stmt; |
fb85abff | 547 | gimple_seq gimplify_stmt_list = NULL; |
548 | ||
549 | enter_e = EDGE_SUCC (guard_bb, 0); | |
550 | enter_e->flags &= ~EDGE_FALLTHRU; | |
551 | enter_e->flags |= EDGE_FALSE_VALUE; | |
552 | gsi = gsi_last_bb (guard_bb); | |
553 | ||
87ae3989 | 554 | cond = force_gimple_operand_1 (cond, &gimplify_stmt_list, is_gimple_condexpr, |
555 | NULL_TREE); | |
23a3430d | 556 | if (gimplify_stmt_list) |
6c6a3430 | 557 | gsi_insert_seq_after (&gsi, gimplify_stmt_list, GSI_NEW_STMT); |
fb85abff | 558 | |
6c6a3430 | 559 | cond_stmt = gimple_build_cond_from_tree (cond, NULL_TREE, NULL_TREE); |
fb85abff | 560 | gsi = gsi_last_bb (guard_bb); |
561 | gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT); | |
562 | ||
563 | /* Add new edge to connect guard block to the merge/loop-exit block. */ | |
6c6a3430 | 564 | new_e = make_edge (guard_bb, guard_to, EDGE_TRUE_VALUE); |
877584e4 | 565 | |
877584e4 | 566 | new_e->probability = probability; |
15492f79 | 567 | if (irreducible_p) |
568 | new_e->flags |= EDGE_IRREDUCIBLE_LOOP; | |
569 | ||
720cfc43 | 570 | enter_e->probability = probability.invert (); |
6c6a3430 | 571 | set_immediate_dominator (CDI_DOMINATORS, guard_to, dom_bb); |
a62a4a78 | 572 | |
573 | /* Split enter_e to preserve LOOPS_HAVE_PREHEADERS. */ | |
574 | if (enter_e->dest->loop_father->header == enter_e->dest) | |
575 | split_edge (enter_e); | |
576 | ||
fb85abff | 577 | return new_e; |
578 | } | |
579 | ||
580 | ||
581 | /* This function verifies that the following restrictions apply to LOOP: | |
5ee742c4 | 582 | (1) it consists of exactly 2 basic blocks - header, and an empty latch |
583 | for innermost loop and 5 basic blocks for outer-loop. | |
584 | (2) it is single entry, single exit | |
585 | (3) its exit condition is the last stmt in the header | |
586 | (4) E is the entry/exit edge of LOOP. | |
fb85abff | 587 | */ |
588 | ||
589 | bool | |
590 | slpeel_can_duplicate_loop_p (const struct loop *loop, const_edge e) | |
591 | { | |
592 | edge exit_e = single_exit (loop); | |
593 | edge entry_e = loop_preheader_edge (loop); | |
1a91d914 | 594 | gcond *orig_cond = get_loop_exit_condition (loop); |
fb85abff | 595 | gimple_stmt_iterator loop_exit_gsi = gsi_last_bb (exit_e->src); |
5ee742c4 | 596 | unsigned int num_bb = loop->inner? 5 : 2; |
fb85abff | 597 | |
51eb70a9 | 598 | /* All loops have an outer scope; the only case loop->outer is NULL is for |
599 | the function itself. */ | |
600 | if (!loop_outer (loop) | |
5ee742c4 | 601 | || loop->num_nodes != num_bb |
fb85abff | 602 | || !empty_block_p (loop->latch) |
603 | || !single_exit (loop) | |
604 | /* Verify that new loop exit condition can be trivially modified. */ | |
605 | || (!orig_cond || orig_cond != gsi_stmt (loop_exit_gsi)) | |
606 | || (e != exit_e && e != entry_e)) | |
607 | return false; | |
608 | ||
609 | return true; | |
610 | } | |
611 | ||
6c6a3430 | 612 | /* If the loop has a virtual PHI, but exit bb doesn't, create a virtual PHI |
613 | in the exit bb and rename all the uses after the loop. This simplifies | |
614 | the *guard[12] routines, which assume loop closed SSA form for all PHIs | |
615 | (but normally loop closed SSA form doesn't require virtual PHIs to be | |
616 | in the same form). Doing this early simplifies the checking what | |
617 | uses should be renamed. */ | |
fb85abff | 618 | |
619 | static void | |
6c6a3430 | 620 | create_lcssa_for_virtual_phi (struct loop *loop) |
fb85abff | 621 | { |
1a91d914 | 622 | gphi_iterator gsi; |
fb85abff | 623 | edge exit_e = single_exit (loop); |
48e1416a | 624 | |
38091110 | 625 | for (gsi = gsi_start_phis (loop->header); !gsi_end_p (gsi); gsi_next (&gsi)) |
7c782c9b | 626 | if (virtual_operand_p (gimple_phi_result (gsi_stmt (gsi)))) |
38091110 | 627 | { |
1a91d914 | 628 | gphi *phi = gsi.phi (); |
38091110 | 629 | for (gsi = gsi_start_phis (exit_e->dest); |
630 | !gsi_end_p (gsi); gsi_next (&gsi)) | |
7c782c9b | 631 | if (virtual_operand_p (gimple_phi_result (gsi_stmt (gsi)))) |
38091110 | 632 | break; |
633 | if (gsi_end_p (gsi)) | |
634 | { | |
f9e245b2 | 635 | tree new_vop = copy_ssa_name (PHI_RESULT (phi)); |
1a91d914 | 636 | gphi *new_phi = create_phi_node (new_vop, exit_e->dest); |
38091110 | 637 | tree vop = PHI_ARG_DEF_FROM_EDGE (phi, EDGE_SUCC (loop->latch, 0)); |
638 | imm_use_iterator imm_iter; | |
42acab1c | 639 | gimple *stmt; |
38091110 | 640 | use_operand_p use_p; |
641 | ||
60d535d2 | 642 | add_phi_arg (new_phi, vop, exit_e, UNKNOWN_LOCATION); |
38091110 | 643 | gimple_phi_set_result (new_phi, new_vop); |
644 | FOR_EACH_IMM_USE_STMT (stmt, imm_iter, vop) | |
480233e7 | 645 | if (stmt != new_phi |
646 | && !flow_bb_inside_loop_p (loop, gimple_bb (stmt))) | |
38091110 | 647 | FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter) |
648 | SET_USE (use_p, new_vop); | |
649 | } | |
650 | break; | |
651 | } | |
fb85abff | 652 | |
fb85abff | 653 | } |
654 | ||
655 | /* Function vect_get_loop_location. | |
656 | ||
657 | Extract the location of the loop in the source code. | |
658 | If the loop is not well formed for vectorization, an estimated | |
659 | location is calculated. | |
660 | Return the loop location if succeed and NULL if not. */ | |
661 | ||
36f39b2e | 662 | source_location |
fb85abff | 663 | find_loop_location (struct loop *loop) |
664 | { | |
42acab1c | 665 | gimple *stmt = NULL; |
fb85abff | 666 | basic_block bb; |
667 | gimple_stmt_iterator si; | |
668 | ||
669 | if (!loop) | |
36f39b2e | 670 | return UNKNOWN_LOCATION; |
fb85abff | 671 | |
672 | stmt = get_loop_exit_condition (loop); | |
673 | ||
b2d978a6 | 674 | if (stmt |
675 | && LOCATION_LOCUS (gimple_location (stmt)) > BUILTINS_LOCATION) | |
fb85abff | 676 | return gimple_location (stmt); |
677 | ||
678 | /* If we got here the loop is probably not "well formed", | |
679 | try to estimate the loop location */ | |
680 | ||
681 | if (!loop->header) | |
36f39b2e | 682 | return UNKNOWN_LOCATION; |
fb85abff | 683 | |
684 | bb = loop->header; | |
685 | ||
686 | for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si)) | |
687 | { | |
688 | stmt = gsi_stmt (si); | |
b2d978a6 | 689 | if (LOCATION_LOCUS (gimple_location (stmt)) > BUILTINS_LOCATION) |
fb85abff | 690 | return gimple_location (stmt); |
691 | } | |
692 | ||
36f39b2e | 693 | return UNKNOWN_LOCATION; |
fb85abff | 694 | } |
695 | ||
6c6a3430 | 696 | /* Return true if PHI defines an IV of the loop to be vectorized. */ |
697 | ||
698 | static bool | |
699 | iv_phi_p (gphi *phi) | |
700 | { | |
701 | if (virtual_operand_p (PHI_RESULT (phi))) | |
702 | return false; | |
703 | ||
704 | stmt_vec_info stmt_info = vinfo_for_stmt (phi); | |
705 | gcc_assert (stmt_info != NULL); | |
706 | if (STMT_VINFO_DEF_TYPE (stmt_info) == vect_reduction_def | |
707 | || STMT_VINFO_DEF_TYPE (stmt_info) == vect_double_reduction_def) | |
708 | return false; | |
709 | ||
710 | return true; | |
711 | } | |
fb85abff | 712 | |
fb85abff | 713 | /* Function vect_can_advance_ivs_p |
714 | ||
48e1416a | 715 | In case the number of iterations that LOOP iterates is unknown at compile |
716 | time, an epilog loop will be generated, and the loop induction variables | |
717 | (IVs) will be "advanced" to the value they are supposed to take just before | |
fb85abff | 718 | the epilog loop. Here we check that the access function of the loop IVs |
719 | and the expression that represents the loop bound are simple enough. | |
720 | These restrictions will be relaxed in the future. */ | |
721 | ||
48e1416a | 722 | bool |
fb85abff | 723 | vect_can_advance_ivs_p (loop_vec_info loop_vinfo) |
724 | { | |
725 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); | |
726 | basic_block bb = loop->header; | |
1a91d914 | 727 | gphi_iterator gsi; |
fb85abff | 728 | |
729 | /* Analyze phi functions of the loop header. */ | |
730 | ||
6d8fb6cf | 731 | if (dump_enabled_p ()) |
78bb46f5 | 732 | dump_printf_loc (MSG_NOTE, vect_location, "vect_can_advance_ivs_p:\n"); |
fb85abff | 733 | for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
734 | { | |
fb85abff | 735 | tree evolution_part; |
736 | ||
6c6a3430 | 737 | gphi *phi = gsi.phi (); |
6d8fb6cf | 738 | if (dump_enabled_p ()) |
fb85abff | 739 | { |
7bd765d4 | 740 | dump_printf_loc (MSG_NOTE, vect_location, "Analyze phi: "); |
741 | dump_gimple_stmt (MSG_NOTE, TDF_SLIM, phi, 0); | |
fb85abff | 742 | } |
743 | ||
744 | /* Skip virtual phi's. The data dependences that are associated with | |
6c6a3430 | 745 | virtual defs/uses (i.e., memory accesses) are analyzed elsewhere. |
fb85abff | 746 | |
6c6a3430 | 747 | Skip reduction phis. */ |
748 | if (!iv_phi_p (phi)) | |
fb85abff | 749 | { |
6d8fb6cf | 750 | if (dump_enabled_p ()) |
6c6a3430 | 751 | dump_printf_loc (MSG_NOTE, vect_location, |
752 | "reduc or virtual phi. skip.\n"); | |
fb85abff | 753 | continue; |
754 | } | |
755 | ||
fb85abff | 756 | /* Analyze the evolution function. */ |
757 | ||
2cd0995e | 758 | evolution_part |
759 | = STMT_VINFO_LOOP_PHI_EVOLUTION_PART (vinfo_for_stmt (phi)); | |
fb85abff | 760 | if (evolution_part == NULL_TREE) |
761 | { | |
6d8fb6cf | 762 | if (dump_enabled_p ()) |
2cd0995e | 763 | dump_printf (MSG_MISSED_OPTIMIZATION, |
78bb46f5 | 764 | "No access function or evolution.\n"); |
fb85abff | 765 | return false; |
766 | } | |
48e1416a | 767 | |
12117f39 | 768 | /* FORNOW: We do not transform initial conditions of IVs |
769 | which evolution functions are not invariants in the loop. */ | |
770 | ||
771 | if (!expr_invariant_in_loop_p (loop, evolution_part)) | |
772 | { | |
773 | if (dump_enabled_p ()) | |
774 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, | |
775 | "evolution not invariant in loop.\n"); | |
776 | return false; | |
777 | } | |
778 | ||
48e1416a | 779 | /* FORNOW: We do not transform initial conditions of IVs |
fb85abff | 780 | which evolution functions are a polynomial of degree >= 2. */ |
781 | ||
782 | if (tree_is_chrec (evolution_part)) | |
12117f39 | 783 | { |
784 | if (dump_enabled_p ()) | |
785 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, | |
786 | "evolution is chrec.\n"); | |
787 | return false; | |
788 | } | |
fb85abff | 789 | } |
790 | ||
791 | return true; | |
792 | } | |
793 | ||
794 | ||
795 | /* Function vect_update_ivs_after_vectorizer. | |
796 | ||
797 | "Advance" the induction variables of LOOP to the value they should take | |
798 | after the execution of LOOP. This is currently necessary because the | |
799 | vectorizer does not handle induction variables that are used after the | |
800 | loop. Such a situation occurs when the last iterations of LOOP are | |
801 | peeled, because: | |
802 | 1. We introduced new uses after LOOP for IVs that were not originally used | |
803 | after LOOP: the IVs of LOOP are now used by an epilog loop. | |
804 | 2. LOOP is going to be vectorized; this means that it will iterate N/VF | |
805 | times, whereas the loop IVs should be bumped N times. | |
806 | ||
807 | Input: | |
808 | - LOOP - a loop that is going to be vectorized. The last few iterations | |
809 | of LOOP were peeled. | |
810 | - NITERS - the number of iterations that LOOP executes (before it is | |
811 | vectorized). i.e, the number of times the ivs should be bumped. | |
812 | - UPDATE_E - a successor edge of LOOP->exit that is on the (only) path | |
813 | coming out from LOOP on which there are uses of the LOOP ivs | |
814 | (this is the path from LOOP->exit to epilog_loop->preheader). | |
815 | ||
816 | The new definitions of the ivs are placed in LOOP->exit. | |
817 | The phi args associated with the edge UPDATE_E in the bb | |
818 | UPDATE_E->dest are updated accordingly. | |
819 | ||
820 | Assumption 1: Like the rest of the vectorizer, this function assumes | |
821 | a single loop exit that has a single predecessor. | |
822 | ||
823 | Assumption 2: The phi nodes in the LOOP header and in update_bb are | |
824 | organized in the same order. | |
825 | ||
826 | Assumption 3: The access function of the ivs is simple enough (see | |
827 | vect_can_advance_ivs_p). This assumption will be relaxed in the future. | |
828 | ||
829 | Assumption 4: Exactly one of the successors of LOOP exit-bb is on a path | |
48e1416a | 830 | coming out of LOOP on which the ivs of LOOP are used (this is the path |
fb85abff | 831 | that leads to the epilog loop; other paths skip the epilog loop). This |
832 | path starts with the edge UPDATE_E, and its destination (denoted update_bb) | |
833 | needs to have its phis updated. | |
834 | */ | |
835 | ||
836 | static void | |
6c6a3430 | 837 | vect_update_ivs_after_vectorizer (loop_vec_info loop_vinfo, |
838 | tree niters, edge update_e) | |
fb85abff | 839 | { |
1a91d914 | 840 | gphi_iterator gsi, gsi1; |
6c6a3430 | 841 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); |
fb85abff | 842 | basic_block update_bb = update_e->dest; |
6c6a3430 | 843 | basic_block exit_bb = single_exit (loop)->dest; |
fb85abff | 844 | |
845 | /* Make sure there exists a single-predecessor exit bb: */ | |
846 | gcc_assert (single_pred_p (exit_bb)); | |
6c6a3430 | 847 | gcc_assert (single_succ_edge (exit_bb) == update_e); |
fb85abff | 848 | |
849 | for (gsi = gsi_start_phis (loop->header), gsi1 = gsi_start_phis (update_bb); | |
850 | !gsi_end_p (gsi) && !gsi_end_p (gsi1); | |
851 | gsi_next (&gsi), gsi_next (&gsi1)) | |
852 | { | |
fb85abff | 853 | tree init_expr; |
1efcacec | 854 | tree step_expr, off; |
855 | tree type; | |
fb85abff | 856 | tree var, ni, ni_name; |
857 | gimple_stmt_iterator last_gsi; | |
858 | ||
6c6a3430 | 859 | gphi *phi = gsi.phi (); |
860 | gphi *phi1 = gsi1.phi (); | |
6d8fb6cf | 861 | if (dump_enabled_p ()) |
6c6a3430 | 862 | { |
863 | dump_printf_loc (MSG_NOTE, vect_location, | |
864 | "vect_update_ivs_after_vectorizer: phi: "); | |
7bd765d4 | 865 | dump_gimple_stmt (MSG_NOTE, TDF_SLIM, phi, 0); |
6c6a3430 | 866 | } |
fb85abff | 867 | |
6c6a3430 | 868 | /* Skip reduction and virtual phis. */ |
869 | if (!iv_phi_p (phi)) | |
fb85abff | 870 | { |
6d8fb6cf | 871 | if (dump_enabled_p ()) |
6c6a3430 | 872 | dump_printf_loc (MSG_NOTE, vect_location, |
873 | "reduc or virtual phi. skip.\n"); | |
fb85abff | 874 | continue; |
875 | } | |
876 | ||
86faead7 | 877 | type = TREE_TYPE (gimple_phi_result (phi)); |
6c6a3430 | 878 | step_expr = STMT_VINFO_LOOP_PHI_EVOLUTION_PART (vinfo_for_stmt (phi)); |
86faead7 | 879 | step_expr = unshare_expr (step_expr); |
48e1416a | 880 | |
fb85abff | 881 | /* FORNOW: We do not support IVs whose evolution function is a polynomial |
882 | of degree >= 2 or exponential. */ | |
86faead7 | 883 | gcc_assert (!tree_is_chrec (step_expr)); |
fb85abff | 884 | |
86faead7 | 885 | init_expr = PHI_ARG_DEF_FROM_EDGE (phi, loop_preheader_edge (loop)); |
fb85abff | 886 | |
1efcacec | 887 | off = fold_build2 (MULT_EXPR, TREE_TYPE (step_expr), |
888 | fold_convert (TREE_TYPE (step_expr), niters), | |
889 | step_expr); | |
86faead7 | 890 | if (POINTER_TYPE_P (type)) |
2cc66f2a | 891 | ni = fold_build_pointer_plus (init_expr, off); |
fb85abff | 892 | else |
86faead7 | 893 | ni = fold_build2 (PLUS_EXPR, type, |
894 | init_expr, fold_convert (type, off)); | |
fb85abff | 895 | |
86faead7 | 896 | var = create_tmp_var (type, "tmp"); |
fb85abff | 897 | |
898 | last_gsi = gsi_last_bb (exit_bb); | |
6c6a3430 | 899 | gimple_seq new_stmts = NULL; |
900 | ni_name = force_gimple_operand (ni, &new_stmts, false, var); | |
901 | /* Exit_bb shouldn't be empty. */ | |
902 | if (!gsi_end_p (last_gsi)) | |
903 | gsi_insert_seq_after (&last_gsi, new_stmts, GSI_SAME_STMT); | |
904 | else | |
905 | gsi_insert_seq_before (&last_gsi, new_stmts, GSI_SAME_STMT); | |
48e1416a | 906 | |
fb85abff | 907 | /* Fix phi expressions in the successor bb. */ |
b123eaab | 908 | adjust_phi_and_debug_stmts (phi1, update_e, ni_name); |
fb85abff | 909 | } |
910 | } | |
911 | ||
6c6a3430 | 912 | /* Function vect_gen_prolog_loop_niters |
97fe80a6 | 913 | |
6c6a3430 | 914 | Generate the number of iterations which should be peeled as prolog for the |
915 | loop represented by LOOP_VINFO. It is calculated as the misalignment of | |
916 | DR - the data reference recorded in LOOP_VINFO_UNALIGNED_DR (LOOP_VINFO). | |
917 | As a result, after the execution of this loop, the data reference DR will | |
918 | refer to an aligned location. The following computation is generated: | |
fb85abff | 919 | |
920 | If the misalignment of DR is known at compile time: | |
921 | addr_mis = int mis = DR_MISALIGNMENT (dr); | |
922 | Else, compute address misalignment in bytes: | |
482a44fa | 923 | addr_mis = addr & (vectype_align - 1) |
fb85abff | 924 | |
6c6a3430 | 925 | prolog_niters = ((VF - addr_mis/elem_size)&(VF-1))/step |
fb85abff | 926 | |
927 | (elem_size = element type size; an element is the scalar element whose type | |
928 | is the inner type of the vectype) | |
929 | ||
6c6a3430 | 930 | The computations will be emitted at the end of BB. We also compute and |
82112bf2 | 931 | store upper bound (included) of the result in BOUND. |
6c6a3430 | 932 | |
fb85abff | 933 | When the step of the data-ref in the loop is not 1 (as in interleaved data |
934 | and SLP), the number of iterations of the prolog must be divided by the step | |
935 | (which is equal to the size of interleaved group). | |
936 | ||
937 | The above formulas assume that VF == number of elements in the vector. This | |
938 | may not hold when there are multiple-types in the loop. | |
939 | In this case, for some data-references in the loop the VF does not represent | |
940 | the number of elements that fit in the vector. Therefore, instead of VF we | |
941 | use TYPE_VECTOR_SUBPARTS. */ | |
942 | ||
48e1416a | 943 | static tree |
6c6a3430 | 944 | vect_gen_prolog_loop_niters (loop_vec_info loop_vinfo, |
945 | basic_block bb, int *bound) | |
fb85abff | 946 | { |
947 | struct data_reference *dr = LOOP_VINFO_UNALIGNED_DR (loop_vinfo); | |
fb85abff | 948 | tree var; |
6c6a3430 | 949 | tree niters_type = TREE_TYPE (LOOP_VINFO_NITERS (loop_vinfo)); |
950 | gimple_seq stmts = NULL, new_stmts = NULL; | |
fb85abff | 951 | tree iters, iters_name; |
42acab1c | 952 | gimple *dr_stmt = DR_STMT (dr); |
fb85abff | 953 | stmt_vec_info stmt_info = vinfo_for_stmt (dr_stmt); |
954 | tree vectype = STMT_VINFO_VECTYPE (stmt_info); | |
aec313e5 | 955 | unsigned int target_align = DR_TARGET_ALIGNMENT (dr); |
fb85abff | 956 | |
313a5120 | 957 | if (LOOP_VINFO_PEELING_FOR_ALIGNMENT (loop_vinfo) > 0) |
fb85abff | 958 | { |
313a5120 | 959 | int npeel = LOOP_VINFO_PEELING_FOR_ALIGNMENT (loop_vinfo); |
fb85abff | 960 | |
6d8fb6cf | 961 | if (dump_enabled_p ()) |
b055bc88 | 962 | dump_printf_loc (MSG_NOTE, vect_location, |
78bb46f5 | 963 | "known peeling = %d.\n", npeel); |
fb85abff | 964 | |
0822b158 | 965 | iters = build_int_cst (niters_type, npeel); |
82112bf2 | 966 | *bound = LOOP_VINFO_PEELING_FOR_ALIGNMENT (loop_vinfo); |
fb85abff | 967 | } |
968 | else | |
969 | { | |
f1b8c740 | 970 | bool negative = tree_int_cst_compare (DR_STEP (dr), size_zero_node) < 0; |
971 | tree offset = negative | |
906a9403 | 972 | ? size_int (-TYPE_VECTOR_SUBPARTS (vectype) + 1) : size_zero_node; |
48e1416a | 973 | tree start_addr = vect_create_addr_base_for_vector_ref (dr_stmt, |
9e879814 | 974 | &stmts, offset); |
3cea8318 | 975 | tree type = unsigned_type_for (TREE_TYPE (start_addr)); |
aec313e5 | 976 | tree target_align_minus_1 = build_int_cst (type, target_align - 1); |
977 | HOST_WIDE_INT elem_size | |
978 | = int_cst_value (TYPE_SIZE_UNIT (TREE_TYPE (vectype))); | |
482a44fa | 979 | tree elem_size_log = build_int_cst (type, exact_log2 (elem_size)); |
aec313e5 | 980 | HOST_WIDE_INT align_in_elems = target_align / elem_size; |
981 | tree align_in_elems_minus_1 = build_int_cst (type, align_in_elems - 1); | |
982 | tree align_in_elems_tree = build_int_cst (type, align_in_elems); | |
983 | tree misalign_in_bytes; | |
984 | tree misalign_in_elems; | |
985 | ||
986 | /* Create: misalign_in_bytes = addr & (target_align - 1). */ | |
987 | misalign_in_bytes | |
988 | = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, start_addr), | |
989 | target_align_minus_1); | |
990 | ||
991 | /* Create: misalign_in_elems = misalign_in_bytes / element_size. */ | |
992 | misalign_in_elems | |
993 | = fold_build2 (RSHIFT_EXPR, type, misalign_in_bytes, elem_size_log); | |
994 | ||
995 | /* Create: (niters_type) ((align_in_elems - misalign_in_elems) | |
996 | & (align_in_elems - 1)). */ | |
f1b8c740 | 997 | if (negative) |
aec313e5 | 998 | iters = fold_build2 (MINUS_EXPR, type, misalign_in_elems, |
999 | align_in_elems_tree); | |
f1b8c740 | 1000 | else |
aec313e5 | 1001 | iters = fold_build2 (MINUS_EXPR, type, align_in_elems_tree, |
1002 | misalign_in_elems); | |
1003 | iters = fold_build2 (BIT_AND_EXPR, type, iters, align_in_elems_minus_1); | |
fb85abff | 1004 | iters = fold_convert (niters_type, iters); |
aec313e5 | 1005 | *bound = align_in_elems - 1; |
fb85abff | 1006 | } |
1007 | ||
6d8fb6cf | 1008 | if (dump_enabled_p ()) |
fb85abff | 1009 | { |
b055bc88 | 1010 | dump_printf_loc (MSG_NOTE, vect_location, |
7bd765d4 | 1011 | "niters for prolog loop: "); |
b055bc88 | 1012 | dump_generic_expr (MSG_NOTE, TDF_SLIM, iters); |
78bb46f5 | 1013 | dump_printf (MSG_NOTE, "\n"); |
fb85abff | 1014 | } |
1015 | ||
1016 | var = create_tmp_var (niters_type, "prolog_loop_niters"); | |
6c6a3430 | 1017 | iters_name = force_gimple_operand (iters, &new_stmts, false, var); |
fb85abff | 1018 | |
6c6a3430 | 1019 | if (new_stmts) |
1020 | gimple_seq_add_seq (&stmts, new_stmts); | |
fb85abff | 1021 | if (stmts) |
1022 | { | |
6c6a3430 | 1023 | gcc_assert (single_succ_p (bb)); |
1024 | gimple_stmt_iterator gsi = gsi_last_bb (bb); | |
1025 | if (gsi_end_p (gsi)) | |
1026 | gsi_insert_seq_before (&gsi, stmts, GSI_SAME_STMT); | |
1027 | else | |
1028 | gsi_insert_seq_after (&gsi, stmts, GSI_SAME_STMT); | |
fb85abff | 1029 | } |
48e1416a | 1030 | return iters_name; |
fb85abff | 1031 | } |
1032 | ||
1033 | ||
1034 | /* Function vect_update_init_of_dr | |
1035 | ||
1036 | NITERS iterations were peeled from LOOP. DR represents a data reference | |
1037 | in LOOP. This function updates the information recorded in DR to | |
48e1416a | 1038 | account for the fact that the first NITERS iterations had already been |
fb85abff | 1039 | executed. Specifically, it updates the OFFSET field of DR. */ |
1040 | ||
1041 | static void | |
1042 | vect_update_init_of_dr (struct data_reference *dr, tree niters) | |
1043 | { | |
1044 | tree offset = DR_OFFSET (dr); | |
48e1416a | 1045 | |
fb85abff | 1046 | niters = fold_build2 (MULT_EXPR, sizetype, |
1047 | fold_convert (sizetype, niters), | |
1048 | fold_convert (sizetype, DR_STEP (dr))); | |
87f9ffa4 | 1049 | offset = fold_build2 (PLUS_EXPR, sizetype, |
1050 | fold_convert (sizetype, offset), niters); | |
fb85abff | 1051 | DR_OFFSET (dr) = offset; |
1052 | } | |
1053 | ||
1054 | ||
1055 | /* Function vect_update_inits_of_drs | |
1056 | ||
48e1416a | 1057 | NITERS iterations were peeled from the loop represented by LOOP_VINFO. |
1058 | This function updates the information recorded for the data references in | |
1059 | the loop to account for the fact that the first NITERS iterations had | |
fb85abff | 1060 | already been executed. Specifically, it updates the initial_condition of |
1061 | the access_function of all the data_references in the loop. */ | |
1062 | ||
1063 | static void | |
1064 | vect_update_inits_of_drs (loop_vec_info loop_vinfo, tree niters) | |
1065 | { | |
1066 | unsigned int i; | |
f1f41a6c | 1067 | vec<data_reference_p> datarefs = LOOP_VINFO_DATAREFS (loop_vinfo); |
fb85abff | 1068 | struct data_reference *dr; |
6c6a3430 | 1069 | |
1070 | if (dump_enabled_p ()) | |
b055bc88 | 1071 | dump_printf_loc (MSG_NOTE, vect_location, |
6c6a3430 | 1072 | "=== vect_update_inits_of_dr ===\n"); |
1073 | ||
1074 | /* Adjust niters to sizetype and insert stmts on loop preheader edge. */ | |
1075 | if (!types_compatible_p (sizetype, TREE_TYPE (niters))) | |
1076 | { | |
1077 | gimple_seq seq; | |
1078 | edge pe = loop_preheader_edge (LOOP_VINFO_LOOP (loop_vinfo)); | |
1079 | tree var = create_tmp_var (sizetype, "prolog_loop_adjusted_niters"); | |
1080 | ||
1081 | niters = fold_convert (sizetype, niters); | |
1082 | niters = force_gimple_operand (niters, &seq, false, var); | |
1083 | if (seq) | |
1084 | { | |
1085 | basic_block new_bb = gsi_insert_seq_on_edge_immediate (pe, seq); | |
1086 | gcc_assert (!new_bb); | |
1087 | } | |
1088 | } | |
fb85abff | 1089 | |
f1f41a6c | 1090 | FOR_EACH_VEC_ELT (datarefs, i, dr) |
fb85abff | 1091 | vect_update_init_of_dr (dr, niters); |
1092 | } | |
1093 | ||
1094 | ||
6c6a3430 | 1095 | /* This function builds ni_name = number of iterations. Statements |
3a815241 | 1096 | are emitted on the loop preheader edge. If NEW_VAR_P is not NULL, set |
1097 | it to TRUE if new ssa_var is generated. */ | |
6c6a3430 | 1098 | |
1099 | tree | |
3a815241 | 1100 | vect_build_loop_niters (loop_vec_info loop_vinfo, bool *new_var_p) |
6c6a3430 | 1101 | { |
1102 | tree ni = unshare_expr (LOOP_VINFO_NITERS (loop_vinfo)); | |
1103 | if (TREE_CODE (ni) == INTEGER_CST) | |
1104 | return ni; | |
1105 | else | |
1106 | { | |
1107 | tree ni_name, var; | |
1108 | gimple_seq stmts = NULL; | |
1109 | edge pe = loop_preheader_edge (LOOP_VINFO_LOOP (loop_vinfo)); | |
1110 | ||
1111 | var = create_tmp_var (TREE_TYPE (ni), "niters"); | |
1112 | ni_name = force_gimple_operand (ni, &stmts, false, var); | |
1113 | if (stmts) | |
3a815241 | 1114 | { |
1115 | gsi_insert_seq_on_edge_immediate (pe, stmts); | |
1116 | if (new_var_p != NULL) | |
1117 | *new_var_p = true; | |
1118 | } | |
6c6a3430 | 1119 | |
1120 | return ni_name; | |
1121 | } | |
1122 | } | |
1123 | ||
82112bf2 | 1124 | /* Calculate the number of iterations above which vectorized loop will be |
1125 | preferred than scalar loop. NITERS_PROLOG is the number of iterations | |
1126 | of prolog loop. If it's integer const, the integer number is also passed | |
1127 | in INT_NITERS_PROLOG. BOUND_PROLOG is the upper bound (included) of | |
1128 | number of iterations of prolog loop. VFM1 is vector factor minus one. | |
1129 | If CHECK_PROFITABILITY is true, TH is the threshold below which scalar | |
1130 | (rather than vectorized) loop will be executed. This function stores | |
1131 | upper bound (included) of the result in BOUND_SCALAR. */ | |
6c6a3430 | 1132 | |
1133 | static tree | |
1134 | vect_gen_scalar_loop_niters (tree niters_prolog, int int_niters_prolog, | |
82112bf2 | 1135 | int bound_prolog, int vfm1, int th, |
1136 | int *bound_scalar, bool check_profitability) | |
6c6a3430 | 1137 | { |
1138 | tree type = TREE_TYPE (niters_prolog); | |
1139 | tree niters = fold_build2 (PLUS_EXPR, type, niters_prolog, | |
82112bf2 | 1140 | build_int_cst (type, vfm1)); |
6c6a3430 | 1141 | |
82112bf2 | 1142 | *bound_scalar = vfm1 + bound_prolog; |
6c6a3430 | 1143 | if (check_profitability) |
1144 | { | |
82112bf2 | 1145 | /* TH indicates the minimum niters of vectorized loop, while we |
1146 | compute the maximum niters of scalar loop. */ | |
1147 | th--; | |
6c6a3430 | 1148 | /* Peeling for constant times. */ |
1149 | if (int_niters_prolog >= 0) | |
1150 | { | |
82112bf2 | 1151 | *bound_scalar = (int_niters_prolog + vfm1 < th |
1152 | ? th | |
1153 | : vfm1 + int_niters_prolog); | |
1154 | return build_int_cst (type, *bound_scalar); | |
6c6a3430 | 1155 | } |
82112bf2 | 1156 | /* Peeling for unknown times. Note BOUND_PROLOG is the upper |
1157 | bound (inlcuded) of niters of prolog loop. */ | |
1158 | if (th >= vfm1 + bound_prolog) | |
6c6a3430 | 1159 | { |
82112bf2 | 1160 | *bound_scalar = th; |
6c6a3430 | 1161 | return build_int_cst (type, th); |
1162 | } | |
82112bf2 | 1163 | /* Need to do runtime comparison, but BOUND_SCALAR remains the same. */ |
1164 | else if (th > vfm1) | |
6c6a3430 | 1165 | return fold_build2 (MAX_EXPR, type, build_int_cst (type, th), niters); |
1166 | } | |
1167 | return niters; | |
1168 | } | |
1169 | ||
1170 | /* This function generates the following statements: | |
fb85abff | 1171 | |
6c6a3430 | 1172 | niters = number of iterations loop executes (after peeling) |
1173 | niters_vector = niters / vf | |
97fe80a6 | 1174 | |
6c6a3430 | 1175 | and places them on the loop preheader edge. NITERS_NO_OVERFLOW is |
1176 | true if NITERS doesn't overflow. */ | |
fb85abff | 1177 | |
1178 | void | |
6c6a3430 | 1179 | vect_gen_vector_loop_niters (loop_vec_info loop_vinfo, tree niters, |
1180 | tree *niters_vector_ptr, bool niters_no_overflow) | |
fb85abff | 1181 | { |
6c6a3430 | 1182 | tree ni_minus_gap, var; |
3a815241 | 1183 | tree niters_vector, type = TREE_TYPE (niters); |
6c6a3430 | 1184 | int vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo); |
1185 | edge pe = loop_preheader_edge (LOOP_VINFO_LOOP (loop_vinfo)); | |
3a815241 | 1186 | tree log_vf = build_int_cst (type, exact_log2 (vf)); |
6c6a3430 | 1187 | |
1188 | /* If epilogue loop is required because of data accesses with gaps, we | |
1189 | subtract one iteration from the total number of iterations here for | |
1190 | correct calculation of RATIO. */ | |
1191 | if (LOOP_VINFO_PEELING_FOR_GAPS (loop_vinfo)) | |
1192 | { | |
3a815241 | 1193 | ni_minus_gap = fold_build2 (MINUS_EXPR, type, niters, |
1194 | build_one_cst (type)); | |
6c6a3430 | 1195 | if (!is_gimple_val (ni_minus_gap)) |
1196 | { | |
3a815241 | 1197 | var = create_tmp_var (type, "ni_gap"); |
6c6a3430 | 1198 | gimple *stmts = NULL; |
1199 | ni_minus_gap = force_gimple_operand (ni_minus_gap, &stmts, | |
1200 | true, var); | |
1201 | gsi_insert_seq_on_edge_immediate (pe, stmts); | |
1202 | } | |
1203 | } | |
1204 | else | |
1205 | ni_minus_gap = niters; | |
1206 | ||
1207 | /* Create: niters >> log2(vf) */ | |
1208 | /* If it's known that niters == number of latch executions + 1 doesn't | |
1209 | overflow, we can generate niters >> log2(vf); otherwise we generate | |
1210 | (niters - vf) >> log2(vf) + 1 by using the fact that we know ratio | |
1211 | will be at least one. */ | |
1212 | if (niters_no_overflow) | |
3a815241 | 1213 | niters_vector = fold_build2 (RSHIFT_EXPR, type, ni_minus_gap, log_vf); |
6c6a3430 | 1214 | else |
1215 | niters_vector | |
3a815241 | 1216 | = fold_build2 (PLUS_EXPR, type, |
1217 | fold_build2 (RSHIFT_EXPR, type, | |
1218 | fold_build2 (MINUS_EXPR, type, ni_minus_gap, | |
1219 | build_int_cst (type, vf)), | |
6c6a3430 | 1220 | log_vf), |
3a815241 | 1221 | build_int_cst (type, 1)); |
6c6a3430 | 1222 | |
1223 | if (!is_gimple_val (niters_vector)) | |
1224 | { | |
3a815241 | 1225 | var = create_tmp_var (type, "bnd"); |
1226 | gimple_seq stmts = NULL; | |
6c6a3430 | 1227 | niters_vector = force_gimple_operand (niters_vector, &stmts, true, var); |
1228 | gsi_insert_seq_on_edge_immediate (pe, stmts); | |
3a815241 | 1229 | /* Peeling algorithm guarantees that vector loop bound is at least ONE, |
1230 | we set range information to make niters analyzer's life easier. */ | |
1231 | if (stmts != NULL) | |
e3d0f65c | 1232 | set_range_info (niters_vector, VR_RANGE, |
1233 | wi::to_wide (build_int_cst (type, 1)), | |
1234 | wi::to_wide (fold_build2 (RSHIFT_EXPR, type, | |
1235 | TYPE_MAX_VALUE (type), | |
1236 | log_vf))); | |
6c6a3430 | 1237 | } |
1238 | *niters_vector_ptr = niters_vector; | |
1239 | ||
1240 | return; | |
1241 | } | |
1242 | ||
1243 | /* Given NITERS_VECTOR which is the number of iterations for vectorized | |
1244 | loop specified by LOOP_VINFO after vectorization, compute the number | |
1245 | of iterations before vectorization (niters_vector * vf) and store it | |
1246 | to NITERS_VECTOR_MULT_VF_PTR. */ | |
1247 | ||
1248 | static void | |
1249 | vect_gen_vector_loop_niters_mult_vf (loop_vec_info loop_vinfo, | |
1250 | tree niters_vector, | |
1251 | tree *niters_vector_mult_vf_ptr) | |
1252 | { | |
1253 | int vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo); | |
fb85abff | 1254 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); |
6c6a3430 | 1255 | tree type = TREE_TYPE (niters_vector); |
1256 | tree log_vf = build_int_cst (type, exact_log2 (vf)); | |
1257 | basic_block exit_bb = single_exit (loop)->dest; | |
fb85abff | 1258 | |
6c6a3430 | 1259 | gcc_assert (niters_vector_mult_vf_ptr != NULL); |
1260 | tree niters_vector_mult_vf = fold_build2 (LSHIFT_EXPR, type, | |
1261 | niters_vector, log_vf); | |
1262 | if (!is_gimple_val (niters_vector_mult_vf)) | |
1263 | { | |
1264 | tree var = create_tmp_var (type, "niters_vector_mult_vf"); | |
1265 | gimple_seq stmts = NULL; | |
1266 | niters_vector_mult_vf = force_gimple_operand (niters_vector_mult_vf, | |
1267 | &stmts, true, var); | |
1268 | gimple_stmt_iterator gsi = gsi_start_bb (exit_bb); | |
1269 | gsi_insert_seq_before (&gsi, stmts, GSI_SAME_STMT); | |
1270 | } | |
1271 | *niters_vector_mult_vf_ptr = niters_vector_mult_vf; | |
1272 | } | |
1273 | ||
1274 | /* Function slpeel_tree_duplicate_loop_to_edge_cfg duplciates FIRST/SECOND | |
1275 | from SECOND/FIRST and puts it at the original loop's preheader/exit | |
1276 | edge, the two loops are arranged as below: | |
1277 | ||
1278 | preheader_a: | |
1279 | first_loop: | |
1280 | header_a: | |
1281 | i_1 = PHI<i_0, i_2>; | |
1282 | ... | |
1283 | i_2 = i_1 + 1; | |
1284 | if (cond_a) | |
1285 | goto latch_a; | |
1286 | else | |
1287 | goto between_bb; | |
1288 | latch_a: | |
1289 | goto header_a; | |
1290 | ||
1291 | between_bb: | |
1292 | ;; i_x = PHI<i_2>; ;; LCSSA phi node to be created for FIRST, | |
1293 | ||
1294 | second_loop: | |
1295 | header_b: | |
1296 | i_3 = PHI<i_0, i_4>; ;; Use of i_0 to be replaced with i_x, | |
1297 | or with i_2 if no LCSSA phi is created | |
1298 | under condition of CREATE_LCSSA_FOR_IV_PHIS. | |
1299 | ... | |
1300 | i_4 = i_3 + 1; | |
1301 | if (cond_b) | |
1302 | goto latch_b; | |
1303 | else | |
1304 | goto exit_bb; | |
1305 | latch_b: | |
1306 | goto header_b; | |
1307 | ||
1308 | exit_bb: | |
1309 | ||
1310 | This function creates loop closed SSA for the first loop; update the | |
1311 | second loop's PHI nodes by replacing argument on incoming edge with the | |
1312 | result of newly created lcssa PHI nodes. IF CREATE_LCSSA_FOR_IV_PHIS | |
1313 | is false, Loop closed ssa phis will only be created for non-iv phis for | |
1314 | the first loop. | |
1315 | ||
1316 | This function assumes exit bb of the first loop is preheader bb of the | |
1317 | second loop, i.e, between_bb in the example code. With PHIs updated, | |
1318 | the second loop will execute rest iterations of the first. */ | |
fb85abff | 1319 | |
6c6a3430 | 1320 | static void |
1321 | slpeel_update_phi_nodes_for_loops (loop_vec_info loop_vinfo, | |
1322 | struct loop *first, struct loop *second, | |
1323 | bool create_lcssa_for_iv_phis) | |
1324 | { | |
1325 | gphi_iterator gsi_update, gsi_orig; | |
1326 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo); | |
1327 | ||
1328 | edge first_latch_e = EDGE_SUCC (first->latch, 0); | |
1329 | edge second_preheader_e = loop_preheader_edge (second); | |
1330 | basic_block between_bb = single_exit (first)->dest; | |
1331 | ||
1332 | gcc_assert (between_bb == second_preheader_e->src); | |
1333 | gcc_assert (single_pred_p (between_bb) && single_succ_p (between_bb)); | |
1334 | /* Either the first loop or the second is the loop to be vectorized. */ | |
1335 | gcc_assert (loop == first || loop == second); | |
1336 | ||
1337 | for (gsi_orig = gsi_start_phis (first->header), | |
1338 | gsi_update = gsi_start_phis (second->header); | |
1339 | !gsi_end_p (gsi_orig) && !gsi_end_p (gsi_update); | |
1340 | gsi_next (&gsi_orig), gsi_next (&gsi_update)) | |
1341 | { | |
1342 | gphi *orig_phi = gsi_orig.phi (); | |
1343 | gphi *update_phi = gsi_update.phi (); | |
1344 | ||
1345 | tree arg = PHI_ARG_DEF_FROM_EDGE (orig_phi, first_latch_e); | |
1346 | /* Generate lcssa PHI node for the first loop. */ | |
1347 | gphi *vect_phi = (loop == first) ? orig_phi : update_phi; | |
1348 | if (create_lcssa_for_iv_phis || !iv_phi_p (vect_phi)) | |
1349 | { | |
1350 | tree new_res = copy_ssa_name (PHI_RESULT (orig_phi)); | |
1351 | gphi *lcssa_phi = create_phi_node (new_res, between_bb); | |
1352 | add_phi_arg (lcssa_phi, arg, single_exit (first), UNKNOWN_LOCATION); | |
1353 | arg = new_res; | |
1354 | } | |
1355 | ||
1356 | /* Update PHI node in the second loop by replacing arg on the loop's | |
1357 | incoming edge. */ | |
1358 | adjust_phi_and_debug_stmts (update_phi, second_preheader_e, arg); | |
1359 | } | |
1360 | } | |
1361 | ||
1362 | /* Function slpeel_add_loop_guard adds guard skipping from the beginning | |
1363 | of SKIP_LOOP to the beginning of UPDATE_LOOP. GUARD_EDGE and MERGE_EDGE | |
1364 | are two pred edges of the merge point before UPDATE_LOOP. The two loops | |
1365 | appear like below: | |
1366 | ||
1367 | guard_bb: | |
1368 | if (cond) | |
1369 | goto merge_bb; | |
1370 | else | |
1371 | goto skip_loop; | |
1372 | ||
1373 | skip_loop: | |
1374 | header_a: | |
1375 | i_1 = PHI<i_0, i_2>; | |
1376 | ... | |
1377 | i_2 = i_1 + 1; | |
1378 | if (cond_a) | |
1379 | goto latch_a; | |
1380 | else | |
1381 | goto exit_a; | |
1382 | latch_a: | |
1383 | goto header_a; | |
1384 | ||
1385 | exit_a: | |
1386 | i_5 = PHI<i_2>; | |
1387 | ||
1388 | merge_bb: | |
1389 | ;; PHI (i_x = PHI<i_0, i_5>) to be created at merge point. | |
1390 | ||
1391 | update_loop: | |
1392 | header_b: | |
1393 | i_3 = PHI<i_5, i_4>; ;; Use of i_5 to be replaced with i_x. | |
1394 | ... | |
1395 | i_4 = i_3 + 1; | |
1396 | if (cond_b) | |
1397 | goto latch_b; | |
1398 | else | |
1399 | goto exit_bb; | |
1400 | latch_b: | |
1401 | goto header_b; | |
1402 | ||
1403 | exit_bb: | |
1404 | ||
1405 | This function creates PHI nodes at merge_bb and replaces the use of i_5 | |
1406 | in the update_loop's PHI node with the result of new PHI result. */ | |
1407 | ||
1408 | static void | |
1409 | slpeel_update_phi_nodes_for_guard1 (struct loop *skip_loop, | |
1410 | struct loop *update_loop, | |
1411 | edge guard_edge, edge merge_edge) | |
1412 | { | |
1413 | source_location merge_loc, guard_loc; | |
1414 | edge orig_e = loop_preheader_edge (skip_loop); | |
1415 | edge update_e = loop_preheader_edge (update_loop); | |
1416 | gphi_iterator gsi_orig, gsi_update; | |
1417 | ||
1418 | for ((gsi_orig = gsi_start_phis (skip_loop->header), | |
1419 | gsi_update = gsi_start_phis (update_loop->header)); | |
1420 | !gsi_end_p (gsi_orig) && !gsi_end_p (gsi_update); | |
1421 | gsi_next (&gsi_orig), gsi_next (&gsi_update)) | |
1422 | { | |
1423 | gphi *orig_phi = gsi_orig.phi (); | |
1424 | gphi *update_phi = gsi_update.phi (); | |
1425 | ||
1426 | /* Generate new phi node at merge bb of the guard. */ | |
1427 | tree new_res = copy_ssa_name (PHI_RESULT (orig_phi)); | |
1428 | gphi *new_phi = create_phi_node (new_res, guard_edge->dest); | |
1429 | ||
1430 | /* Merge bb has two incoming edges: GUARD_EDGE and MERGE_EDGE. Set the | |
1431 | args in NEW_PHI for these edges. */ | |
1432 | tree merge_arg = PHI_ARG_DEF_FROM_EDGE (update_phi, update_e); | |
1433 | tree guard_arg = PHI_ARG_DEF_FROM_EDGE (orig_phi, orig_e); | |
1434 | merge_loc = gimple_phi_arg_location_from_edge (update_phi, update_e); | |
1435 | guard_loc = gimple_phi_arg_location_from_edge (orig_phi, orig_e); | |
1436 | add_phi_arg (new_phi, merge_arg, merge_edge, merge_loc); | |
1437 | add_phi_arg (new_phi, guard_arg, guard_edge, guard_loc); | |
1438 | ||
1439 | /* Update phi in UPDATE_PHI. */ | |
1440 | adjust_phi_and_debug_stmts (update_phi, update_e, new_res); | |
1441 | } | |
1442 | } | |
1443 | ||
1444 | /* LCSSA_PHI is a lcssa phi of EPILOG loop which is copied from LOOP, | |
1445 | this function searches for the corresponding lcssa phi node in exit | |
1446 | bb of LOOP. If it is found, return the phi result; otherwise return | |
1447 | NULL. */ | |
1448 | ||
1449 | static tree | |
1450 | find_guard_arg (struct loop *loop, struct loop *epilog ATTRIBUTE_UNUSED, | |
1451 | gphi *lcssa_phi) | |
1452 | { | |
1453 | gphi_iterator gsi; | |
1454 | edge e = single_exit (loop); | |
1455 | ||
1456 | gcc_assert (single_pred_p (e->dest)); | |
1457 | for (gsi = gsi_start_phis (e->dest); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1458 | { | |
1459 | gphi *phi = gsi.phi (); | |
1460 | if (operand_equal_p (PHI_ARG_DEF (phi, 0), | |
1461 | PHI_ARG_DEF (lcssa_phi, 0), 0)) | |
1462 | return PHI_RESULT (phi); | |
1463 | } | |
1464 | return NULL_TREE; | |
1465 | } | |
1466 | ||
1467 | /* LOOP and EPILOG are two consecutive loops in CFG and EPILOG is copied | |
1468 | from LOOP. Function slpeel_add_loop_guard adds guard skipping from a | |
1469 | point between the two loops to the end of EPILOG. Edges GUARD_EDGE | |
1470 | and MERGE_EDGE are the two pred edges of merge_bb at the end of EPILOG. | |
1471 | The CFG looks like: | |
1472 | ||
1473 | loop: | |
1474 | header_a: | |
1475 | i_1 = PHI<i_0, i_2>; | |
1476 | ... | |
1477 | i_2 = i_1 + 1; | |
1478 | if (cond_a) | |
1479 | goto latch_a; | |
1480 | else | |
1481 | goto exit_a; | |
1482 | latch_a: | |
1483 | goto header_a; | |
1484 | ||
1485 | exit_a: | |
1486 | ||
1487 | guard_bb: | |
1488 | if (cond) | |
1489 | goto merge_bb; | |
1490 | else | |
1491 | goto epilog_loop; | |
1492 | ||
1493 | ;; fall_through_bb | |
1494 | ||
1495 | epilog_loop: | |
1496 | header_b: | |
1497 | i_3 = PHI<i_2, i_4>; | |
1498 | ... | |
1499 | i_4 = i_3 + 1; | |
1500 | if (cond_b) | |
1501 | goto latch_b; | |
1502 | else | |
1503 | goto merge_bb; | |
1504 | latch_b: | |
1505 | goto header_b; | |
1506 | ||
1507 | merge_bb: | |
1508 | ; PHI node (i_y = PHI<i_2, i_4>) to be created at merge point. | |
1509 | ||
1510 | exit_bb: | |
1511 | i_x = PHI<i_4>; ;Use of i_4 to be replaced with i_y in merge_bb. | |
1512 | ||
1513 | For each name used out side EPILOG (i.e - for each name that has a lcssa | |
1514 | phi in exit_bb) we create a new PHI in merge_bb. The new PHI has two | |
1515 | args corresponding to GUARD_EDGE and MERGE_EDGE. Arg for MERGE_EDGE is | |
1516 | the arg of the original PHI in exit_bb, arg for GUARD_EDGE is defined | |
1517 | by LOOP and is found in the exit bb of LOOP. Arg of the original PHI | |
1518 | in exit_bb will also be updated. */ | |
1519 | ||
1520 | static void | |
1521 | slpeel_update_phi_nodes_for_guard2 (struct loop *loop, struct loop *epilog, | |
1522 | edge guard_edge, edge merge_edge) | |
1523 | { | |
1524 | gphi_iterator gsi; | |
1525 | basic_block merge_bb = guard_edge->dest; | |
1526 | ||
1527 | gcc_assert (single_succ_p (merge_bb)); | |
1528 | edge e = single_succ_edge (merge_bb); | |
1529 | basic_block exit_bb = e->dest; | |
1530 | gcc_assert (single_pred_p (exit_bb)); | |
1531 | gcc_assert (single_pred (exit_bb) == single_exit (epilog)->dest); | |
1532 | ||
1533 | for (gsi = gsi_start_phis (exit_bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1534 | { | |
1535 | gphi *update_phi = gsi.phi (); | |
1536 | tree old_arg = PHI_ARG_DEF (update_phi, 0); | |
1537 | /* This loop-closed-phi actually doesn't represent a use out of the | |
1538 | loop - the phi arg is a constant. */ | |
1539 | if (TREE_CODE (old_arg) != SSA_NAME) | |
1540 | continue; | |
1541 | ||
1542 | tree merge_arg = get_current_def (old_arg); | |
1543 | if (!merge_arg) | |
1544 | merge_arg = old_arg; | |
1545 | ||
1546 | tree guard_arg = find_guard_arg (loop, epilog, update_phi); | |
1547 | /* If the var is live after loop but not a reduction, we simply | |
1548 | use the old arg. */ | |
1549 | if (!guard_arg) | |
1550 | guard_arg = old_arg; | |
1551 | ||
1552 | /* Create new phi node in MERGE_BB: */ | |
1553 | tree new_res = copy_ssa_name (PHI_RESULT (update_phi)); | |
1554 | gphi *merge_phi = create_phi_node (new_res, merge_bb); | |
1555 | ||
1556 | /* MERGE_BB has two incoming edges: GUARD_EDGE and MERGE_EDGE, Set | |
1557 | the two PHI args in merge_phi for these edges. */ | |
1558 | add_phi_arg (merge_phi, merge_arg, merge_edge, UNKNOWN_LOCATION); | |
1559 | add_phi_arg (merge_phi, guard_arg, guard_edge, UNKNOWN_LOCATION); | |
1560 | ||
1561 | /* Update the original phi in exit_bb. */ | |
1562 | adjust_phi_and_debug_stmts (update_phi, e, new_res); | |
1563 | } | |
1564 | } | |
1565 | ||
1566 | /* EPILOG loop is duplicated from the original loop for vectorizing, | |
1567 | the arg of its loop closed ssa PHI needs to be updated. */ | |
1568 | ||
1569 | static void | |
1570 | slpeel_update_phi_nodes_for_lcssa (struct loop *epilog) | |
1571 | { | |
1572 | gphi_iterator gsi; | |
1573 | basic_block exit_bb = single_exit (epilog)->dest; | |
1574 | ||
1575 | gcc_assert (single_pred_p (exit_bb)); | |
1576 | edge e = EDGE_PRED (exit_bb, 0); | |
1577 | for (gsi = gsi_start_phis (exit_bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1578 | rename_use_op (PHI_ARG_DEF_PTR_FROM_EDGE (gsi.phi (), e)); | |
1579 | } | |
1580 | ||
1581 | /* Function vect_do_peeling. | |
1582 | ||
1583 | Input: | |
1584 | - LOOP_VINFO: Represent a loop to be vectorized, which looks like: | |
1585 | ||
1586 | preheader: | |
1587 | LOOP: | |
1588 | header_bb: | |
1589 | loop_body | |
1590 | if (exit_loop_cond) goto exit_bb | |
1591 | else goto header_bb | |
1592 | exit_bb: | |
1593 | ||
1594 | - NITERS: The number of iterations of the loop. | |
1595 | - NITERSM1: The number of iterations of the loop's latch. | |
1596 | - NITERS_NO_OVERFLOW: No overflow in computing NITERS. | |
1597 | - TH, CHECK_PROFITABILITY: Threshold of niters to vectorize loop if | |
1598 | CHECK_PROFITABILITY is true. | |
1599 | Output: | |
1600 | - NITERS_VECTOR: The number of iterations of loop after vectorization. | |
1601 | ||
1602 | This function peels prolog and epilog from the loop, adds guards skipping | |
1603 | PROLOG and EPILOG for various conditions. As a result, the changed CFG | |
1604 | would look like: | |
1605 | ||
1606 | guard_bb_1: | |
1607 | if (prefer_scalar_loop) goto merge_bb_1 | |
1608 | else goto guard_bb_2 | |
1609 | ||
1610 | guard_bb_2: | |
1611 | if (skip_prolog) goto merge_bb_2 | |
1612 | else goto prolog_preheader | |
1613 | ||
1614 | prolog_preheader: | |
1615 | PROLOG: | |
1616 | prolog_header_bb: | |
1617 | prolog_body | |
1618 | if (exit_prolog_cond) goto prolog_exit_bb | |
1619 | else goto prolog_header_bb | |
1620 | prolog_exit_bb: | |
1621 | ||
1622 | merge_bb_2: | |
1623 | ||
1624 | vector_preheader: | |
1625 | VECTOR LOOP: | |
1626 | vector_header_bb: | |
1627 | vector_body | |
1628 | if (exit_vector_cond) goto vector_exit_bb | |
1629 | else goto vector_header_bb | |
1630 | vector_exit_bb: | |
1631 | ||
1632 | guard_bb_3: | |
1633 | if (skip_epilog) goto merge_bb_3 | |
1634 | else goto epilog_preheader | |
1635 | ||
1636 | merge_bb_1: | |
1637 | ||
1638 | epilog_preheader: | |
1639 | EPILOG: | |
1640 | epilog_header_bb: | |
1641 | epilog_body | |
1642 | if (exit_epilog_cond) goto merge_bb_3 | |
1643 | else goto epilog_header_bb | |
1644 | ||
1645 | merge_bb_3: | |
1646 | ||
1647 | Note this function peels prolog and epilog only if it's necessary, | |
1648 | as well as guards. | |
5b631e09 | 1649 | Returns created epilogue or NULL. |
6c6a3430 | 1650 | |
1651 | TODO: Guard for prefer_scalar_loop should be emitted along with | |
1652 | versioning conditions if loop versioning is needed. */ | |
1653 | ||
5b631e09 | 1654 | |
1655 | struct loop * | |
6c6a3430 | 1656 | vect_do_peeling (loop_vec_info loop_vinfo, tree niters, tree nitersm1, |
1657 | tree *niters_vector, int th, bool check_profitability, | |
1658 | bool niters_no_overflow) | |
1659 | { | |
1660 | edge e, guard_e; | |
1661 | tree type = TREE_TYPE (niters), guard_cond; | |
1662 | basic_block guard_bb, guard_to; | |
720cfc43 | 1663 | profile_probability prob_prolog, prob_vector, prob_epilog; |
82112bf2 | 1664 | int bound_prolog = 0, bound_scalar = 0, bound = 0; |
6c6a3430 | 1665 | int vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo); |
1666 | int prolog_peeling = LOOP_VINFO_PEELING_FOR_ALIGNMENT (loop_vinfo); | |
1667 | bool epilog_peeling = (LOOP_VINFO_PEELING_FOR_NITER (loop_vinfo) | |
1668 | || LOOP_VINFO_PEELING_FOR_GAPS (loop_vinfo)); | |
1669 | ||
1670 | if (!prolog_peeling && !epilog_peeling) | |
5b631e09 | 1671 | return NULL; |
6c6a3430 | 1672 | |
720cfc43 | 1673 | prob_vector = profile_probability::guessed_always ().apply_scale (9, 10); |
6c6a3430 | 1674 | if ((vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo)) == 2) |
1675 | vf = 3; | |
720cfc43 | 1676 | prob_prolog = prob_epilog = profile_probability::guessed_always () |
1677 | .apply_scale (vf - 1, vf); | |
6c6a3430 | 1678 | vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo); |
1679 | ||
5b631e09 | 1680 | struct loop *prolog, *epilog = NULL, *loop = LOOP_VINFO_LOOP (loop_vinfo); |
6c6a3430 | 1681 | struct loop *first_loop = loop; |
15492f79 | 1682 | bool irred_flag = loop_preheader_edge (loop)->flags & EDGE_IRREDUCIBLE_LOOP; |
6c6a3430 | 1683 | create_lcssa_for_virtual_phi (loop); |
1684 | update_ssa (TODO_update_ssa_only_virtuals); | |
1685 | ||
1686 | if (MAY_HAVE_DEBUG_STMTS) | |
1687 | { | |
1688 | gcc_assert (!adjust_vec.exists ()); | |
1689 | adjust_vec.create (32); | |
1690 | } | |
fb85abff | 1691 | initialize_original_copy_tables (); |
1692 | ||
6c6a3430 | 1693 | /* Prolog loop may be skipped. */ |
1694 | bool skip_prolog = (prolog_peeling != 0); | |
32236f80 | 1695 | /* Skip to epilog if scalar loop may be preferred. It's only needed |
1696 | when we peel for epilog loop and when it hasn't been checked with | |
1697 | loop versioning. */ | |
1698 | bool skip_vector = (!LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo) | |
1699 | && !LOOP_REQUIRES_VERSIONING (loop_vinfo)); | |
6c6a3430 | 1700 | /* Epilog loop must be executed if the number of iterations for epilog |
1701 | loop is known at compile time, otherwise we need to add a check at | |
1702 | the end of vector loop and skip to the end of epilog loop. */ | |
1703 | bool skip_epilog = (prolog_peeling < 0 | |
1704 | || !LOOP_VINFO_NITERS_KNOWN_P (loop_vinfo)); | |
1705 | /* PEELING_FOR_GAPS is special because epilog loop must be executed. */ | |
1706 | if (LOOP_VINFO_PEELING_FOR_GAPS (loop_vinfo)) | |
1707 | skip_epilog = false; | |
1708 | ||
1709 | /* Record the anchor bb at which guard should be placed if scalar loop | |
1710 | may be preferred. */ | |
1711 | basic_block anchor = loop_preheader_edge (loop)->src; | |
1712 | if (skip_vector) | |
c214c858 | 1713 | { |
1714 | split_edge (loop_preheader_edge (loop)); | |
1715 | ||
1716 | /* Due to the order in which we peel prolog and epilog, we first | |
1717 | propagate probability to the whole loop. The purpose is to | |
1718 | avoid adjusting probabilities of both prolog and vector loops | |
1719 | separately. Note in this case, the probability of epilog loop | |
1720 | needs to be scaled back later. */ | |
1721 | basic_block bb_before_loop = loop_preheader_edge (loop)->src; | |
720cfc43 | 1722 | if (prob_vector.initialized_p ()) |
ca69b069 | 1723 | scale_bbs_frequencies (&bb_before_loop, 1, prob_vector); |
1724 | scale_loop_profile (loop, prob_vector, bound); | |
c214c858 | 1725 | } |
6c6a3430 | 1726 | |
1727 | tree niters_prolog = build_int_cst (type, 0); | |
1728 | source_location loop_loc = find_loop_location (loop); | |
1729 | struct loop *scalar_loop = LOOP_VINFO_SCALAR_LOOP (loop_vinfo); | |
1730 | if (prolog_peeling) | |
2f630015 | 1731 | { |
6c6a3430 | 1732 | e = loop_preheader_edge (loop); |
1733 | if (!slpeel_can_duplicate_loop_p (loop, e)) | |
2f630015 | 1734 | { |
6c6a3430 | 1735 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, loop_loc, |
1736 | "loop can't be duplicated to preheader edge.\n"); | |
1737 | gcc_unreachable (); | |
1738 | } | |
1739 | /* Peel prolog and put it on preheader edge of loop. */ | |
1740 | prolog = slpeel_tree_duplicate_loop_to_edge_cfg (loop, scalar_loop, e); | |
1741 | if (!prolog) | |
1742 | { | |
1743 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, loop_loc, | |
1744 | "slpeel_tree_duplicate_loop_to_edge_cfg failed.\n"); | |
1745 | gcc_unreachable (); | |
1746 | } | |
1747 | slpeel_update_phi_nodes_for_loops (loop_vinfo, prolog, loop, true); | |
1748 | first_loop = prolog; | |
1749 | reset_original_copy_tables (); | |
1750 | ||
1751 | /* Generate and update the number of iterations for prolog loop. */ | |
1752 | niters_prolog = vect_gen_prolog_loop_niters (loop_vinfo, anchor, | |
1753 | &bound_prolog); | |
1754 | slpeel_make_loop_iterate_ntimes (prolog, niters_prolog); | |
1755 | ||
1756 | /* Skip the prolog loop. */ | |
1757 | if (skip_prolog) | |
1758 | { | |
1759 | guard_cond = fold_build2 (EQ_EXPR, boolean_type_node, | |
1760 | niters_prolog, build_int_cst (type, 0)); | |
1761 | guard_bb = loop_preheader_edge (prolog)->src; | |
c214c858 | 1762 | basic_block bb_after_prolog = loop_preheader_edge (loop)->src; |
6c6a3430 | 1763 | guard_to = split_edge (loop_preheader_edge (loop)); |
1764 | guard_e = slpeel_add_loop_guard (guard_bb, guard_cond, | |
1765 | guard_to, guard_bb, | |
720cfc43 | 1766 | prob_prolog.invert (), |
15492f79 | 1767 | irred_flag); |
6c6a3430 | 1768 | e = EDGE_PRED (guard_to, 0); |
1769 | e = (e != guard_e ? e : EDGE_PRED (guard_to, 1)); | |
1770 | slpeel_update_phi_nodes_for_guard1 (prolog, loop, guard_e, e); | |
c214c858 | 1771 | |
ca69b069 | 1772 | scale_bbs_frequencies (&bb_after_prolog, 1, prob_prolog); |
1773 | scale_loop_profile (prolog, prob_prolog, bound_prolog); | |
6c6a3430 | 1774 | } |
1775 | /* Update init address of DRs. */ | |
1776 | vect_update_inits_of_drs (loop_vinfo, niters_prolog); | |
1777 | /* Update niters for vector loop. */ | |
1778 | LOOP_VINFO_NITERS (loop_vinfo) | |
1779 | = fold_build2 (MINUS_EXPR, type, niters, niters_prolog); | |
1780 | LOOP_VINFO_NITERSM1 (loop_vinfo) | |
1781 | = fold_build2 (MINUS_EXPR, type, | |
1782 | LOOP_VINFO_NITERSM1 (loop_vinfo), niters_prolog); | |
3a815241 | 1783 | bool new_var_p = false; |
1784 | niters = vect_build_loop_niters (loop_vinfo, &new_var_p); | |
1785 | /* It's guaranteed that vector loop bound before vectorization is at | |
1786 | least VF, so set range information for newly generated var. */ | |
1787 | if (new_var_p) | |
1788 | set_range_info (niters, VR_RANGE, | |
e3d0f65c | 1789 | wi::to_wide (build_int_cst (type, vf)), |
1790 | wi::to_wide (TYPE_MAX_VALUE (type))); | |
6c6a3430 | 1791 | |
82112bf2 | 1792 | /* Prolog iterates at most bound_prolog times, latch iterates at |
1793 | most bound_prolog - 1 times. */ | |
1794 | record_niter_bound (prolog, bound_prolog - 1, false, true); | |
6c6a3430 | 1795 | delete_update_ssa (); |
1796 | adjust_vec_debug_stmts (); | |
1797 | scev_reset (); | |
2f630015 | 1798 | } |
1799 | ||
6c6a3430 | 1800 | if (epilog_peeling) |
1801 | { | |
1802 | e = single_exit (loop); | |
1803 | if (!slpeel_can_duplicate_loop_p (loop, e)) | |
1804 | { | |
1805 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, loop_loc, | |
1806 | "loop can't be duplicated to exit edge.\n"); | |
1807 | gcc_unreachable (); | |
1808 | } | |
1809 | /* Peel epilog and put it on exit edge of loop. */ | |
1810 | epilog = slpeel_tree_duplicate_loop_to_edge_cfg (loop, scalar_loop, e); | |
1811 | if (!epilog) | |
1812 | { | |
1813 | dump_printf_loc (MSG_MISSED_OPTIMIZATION, loop_loc, | |
1814 | "slpeel_tree_duplicate_loop_to_edge_cfg failed.\n"); | |
1815 | gcc_unreachable (); | |
1816 | } | |
1817 | slpeel_update_phi_nodes_for_loops (loop_vinfo, loop, epilog, false); | |
1818 | ||
1819 | /* Scalar version loop may be preferred. In this case, add guard | |
1820 | and skip to epilog. Note this only happens when the number of | |
1821 | iterations of loop is unknown at compile time, otherwise this | |
1822 | won't be vectorized. */ | |
1823 | if (skip_vector) | |
1824 | { | |
82112bf2 | 1825 | /* Additional epilogue iteration is peeled if gap exists. */ |
1826 | bool peel_for_gaps = LOOP_VINFO_PEELING_FOR_GAPS (loop_vinfo); | |
6c6a3430 | 1827 | tree t = vect_gen_scalar_loop_niters (niters_prolog, prolog_peeling, |
82112bf2 | 1828 | bound_prolog, |
1829 | peel_for_gaps ? vf : vf - 1, | |
1830 | th, &bound_scalar, | |
6c6a3430 | 1831 | check_profitability); |
82112bf2 | 1832 | /* Build guard against NITERSM1 since NITERS may overflow. */ |
1833 | guard_cond = fold_build2 (LT_EXPR, boolean_type_node, nitersm1, t); | |
6c6a3430 | 1834 | guard_bb = anchor; |
1835 | guard_to = split_edge (loop_preheader_edge (epilog)); | |
1836 | guard_e = slpeel_add_loop_guard (guard_bb, guard_cond, | |
1837 | guard_to, guard_bb, | |
720cfc43 | 1838 | prob_vector.invert (), |
15492f79 | 1839 | irred_flag); |
6c6a3430 | 1840 | e = EDGE_PRED (guard_to, 0); |
1841 | e = (e != guard_e ? e : EDGE_PRED (guard_to, 1)); | |
1842 | slpeel_update_phi_nodes_for_guard1 (first_loop, epilog, guard_e, e); | |
c214c858 | 1843 | |
1844 | /* Simply propagate profile info from guard_bb to guard_to which is | |
1845 | a merge point of control flow. */ | |
1846 | guard_to->frequency = guard_bb->frequency; | |
1847 | guard_to->count = guard_bb->count; | |
ca69b069 | 1848 | /* Scale probability of epilog loop back. |
1849 | FIXME: We should avoid scaling down and back up. Profile may | |
1850 | get lost if we scale down to 0. */ | |
720cfc43 | 1851 | int scale_up = REG_BR_PROB_BASE * REG_BR_PROB_BASE |
1852 | / prob_vector.to_reg_br_prob_base (); | |
12b55cc8 | 1853 | basic_block *bbs = get_loop_body (epilog); |
1854 | scale_bbs_frequencies_int (bbs, epilog->num_nodes, scale_up, | |
ca69b069 | 1855 | REG_BR_PROB_BASE); |
1856 | free (bbs); | |
6c6a3430 | 1857 | } |
fb85abff | 1858 | |
c214c858 | 1859 | basic_block bb_before_epilog = loop_preheader_edge (epilog)->src; |
6c6a3430 | 1860 | tree niters_vector_mult_vf; |
1861 | /* If loop is peeled for non-zero constant times, now niters refers to | |
1862 | orig_niters - prolog_peeling, it won't overflow even the orig_niters | |
1863 | overflows. */ | |
1864 | niters_no_overflow |= (prolog_peeling > 0); | |
1865 | vect_gen_vector_loop_niters (loop_vinfo, niters, | |
1866 | niters_vector, niters_no_overflow); | |
1867 | vect_gen_vector_loop_niters_mult_vf (loop_vinfo, *niters_vector, | |
1868 | &niters_vector_mult_vf); | |
1869 | /* Update IVs of original loop as if they were advanced by | |
1870 | niters_vector_mult_vf steps. */ | |
1871 | gcc_checking_assert (vect_can_advance_ivs_p (loop_vinfo)); | |
1872 | edge update_e = skip_vector ? e : loop_preheader_edge (epilog); | |
1873 | vect_update_ivs_after_vectorizer (loop_vinfo, niters_vector_mult_vf, | |
1874 | update_e); | |
1875 | ||
1876 | if (skip_epilog) | |
1877 | { | |
1878 | guard_cond = fold_build2 (EQ_EXPR, boolean_type_node, | |
1879 | niters, niters_vector_mult_vf); | |
1880 | guard_bb = single_exit (loop)->dest; | |
1881 | guard_to = split_edge (single_exit (epilog)); | |
1882 | guard_e = slpeel_add_loop_guard (guard_bb, guard_cond, guard_to, | |
1883 | skip_vector ? anchor : guard_bb, | |
720cfc43 | 1884 | prob_epilog.invert (), |
15492f79 | 1885 | irred_flag); |
6c6a3430 | 1886 | slpeel_update_phi_nodes_for_guard2 (loop, epilog, guard_e, |
1887 | single_exit (epilog)); | |
c214c858 | 1888 | /* Only need to handle basic block before epilog loop if it's not |
1889 | the guard_bb, which is the case when skip_vector is true. */ | |
1890 | if (guard_bb != bb_before_epilog) | |
1891 | { | |
720cfc43 | 1892 | prob_epilog = prob_vector * prob_epilog + prob_vector.invert (); |
c214c858 | 1893 | |
ca69b069 | 1894 | scale_bbs_frequencies (&bb_before_epilog, 1, prob_epilog); |
c214c858 | 1895 | } |
ca69b069 | 1896 | scale_loop_profile (epilog, prob_epilog, bound); |
6c6a3430 | 1897 | } |
1898 | else | |
1899 | slpeel_update_phi_nodes_for_lcssa (epilog); | |
fb85abff | 1900 | |
82112bf2 | 1901 | bound = LOOP_VINFO_PEELING_FOR_GAPS (loop_vinfo) ? vf - 1 : vf - 2; |
6c6a3430 | 1902 | /* We share epilog loop with scalar version loop. */ |
82112bf2 | 1903 | bound = MAX (bound, bound_scalar - 1); |
1904 | record_niter_bound (epilog, bound, false, true); | |
6c6a3430 | 1905 | |
1906 | delete_update_ssa (); | |
1907 | adjust_vec_debug_stmts (); | |
1908 | scev_reset (); | |
1909 | } | |
1910 | adjust_vec.release (); | |
fb85abff | 1911 | free_original_copy_tables (); |
5b631e09 | 1912 | |
1913 | return epilog; | |
fb85abff | 1914 | } |
1915 | ||
d5e80d93 | 1916 | /* Function vect_create_cond_for_niters_checks. |
1917 | ||
1918 | Create a conditional expression that represents the run-time checks for | |
1919 | loop's niter. The loop is guaranteed to to terminate if the run-time | |
1920 | checks hold. | |
1921 | ||
1922 | Input: | |
1923 | COND_EXPR - input conditional expression. New conditions will be chained | |
1924 | with logical AND operation. If it is NULL, then the function | |
1925 | is used to return the number of alias checks. | |
1926 | LOOP_VINFO - field LOOP_VINFO_MAY_ALIAS_STMTS contains the list of ddrs | |
1927 | to be checked. | |
1928 | ||
1929 | Output: | |
1930 | COND_EXPR - conditional expression. | |
1931 | ||
1932 | The returned COND_EXPR is the conditional expression to be used in the | |
1933 | if statement that controls which version of the loop gets executed at | |
1934 | runtime. */ | |
1935 | ||
1936 | static void | |
1937 | vect_create_cond_for_niters_checks (loop_vec_info loop_vinfo, tree *cond_expr) | |
1938 | { | |
1939 | tree part_cond_expr = LOOP_VINFO_NITERS_ASSUMPTIONS (loop_vinfo); | |
1940 | ||
1941 | if (*cond_expr) | |
1942 | *cond_expr = fold_build2 (TRUTH_AND_EXPR, boolean_type_node, | |
1943 | *cond_expr, part_cond_expr); | |
1944 | else | |
1945 | *cond_expr = part_cond_expr; | |
1946 | } | |
fb85abff | 1947 | |
f68a7726 | 1948 | /* Set *COND_EXPR to a tree that is true when both the original *COND_EXPR |
1949 | and PART_COND_EXPR are true. Treat a null *COND_EXPR as "true". */ | |
1950 | ||
1951 | static void | |
1952 | chain_cond_expr (tree *cond_expr, tree part_cond_expr) | |
1953 | { | |
1954 | if (*cond_expr) | |
1955 | *cond_expr = fold_build2 (TRUTH_AND_EXPR, boolean_type_node, | |
1956 | *cond_expr, part_cond_expr); | |
1957 | else | |
1958 | *cond_expr = part_cond_expr; | |
1959 | } | |
1960 | ||
fb85abff | 1961 | /* Function vect_create_cond_for_align_checks. |
1962 | ||
1963 | Create a conditional expression that represents the alignment checks for | |
1964 | all of data references (array element references) whose alignment must be | |
1965 | checked at runtime. | |
1966 | ||
1967 | Input: | |
1968 | COND_EXPR - input conditional expression. New conditions will be chained | |
1969 | with logical AND operation. | |
1970 | LOOP_VINFO - two fields of the loop information are used. | |
1971 | LOOP_VINFO_PTR_MASK is the mask used to check the alignment. | |
1972 | LOOP_VINFO_MAY_MISALIGN_STMTS contains the refs to be checked. | |
1973 | ||
1974 | Output: | |
1975 | COND_EXPR_STMT_LIST - statements needed to construct the conditional | |
1976 | expression. | |
1977 | The returned value is the conditional expression to be used in the if | |
1978 | statement that controls which version of the loop gets executed at runtime. | |
1979 | ||
1980 | The algorithm makes two assumptions: | |
1981 | 1) The number of bytes "n" in a vector is a power of 2. | |
1982 | 2) An address "a" is aligned if a%n is zero and that this | |
1983 | test can be done as a&(n-1) == 0. For example, for 16 | |
1984 | byte vectors the test is a&0xf == 0. */ | |
1985 | ||
1986 | static void | |
1987 | vect_create_cond_for_align_checks (loop_vec_info loop_vinfo, | |
1988 | tree *cond_expr, | |
1989 | gimple_seq *cond_expr_stmt_list) | |
1990 | { | |
42acab1c | 1991 | vec<gimple *> may_misalign_stmts |
fb85abff | 1992 | = LOOP_VINFO_MAY_MISALIGN_STMTS (loop_vinfo); |
42acab1c | 1993 | gimple *ref_stmt; |
fb85abff | 1994 | int mask = LOOP_VINFO_PTR_MASK (loop_vinfo); |
1995 | tree mask_cst; | |
1996 | unsigned int i; | |
fb85abff | 1997 | tree int_ptrsize_type; |
1998 | char tmp_name[20]; | |
1999 | tree or_tmp_name = NULL_TREE; | |
03d37e4e | 2000 | tree and_tmp_name; |
42acab1c | 2001 | gimple *and_stmt; |
fb85abff | 2002 | tree ptrsize_zero; |
2003 | tree part_cond_expr; | |
2004 | ||
2005 | /* Check that mask is one less than a power of 2, i.e., mask is | |
2006 | all zeros followed by all ones. */ | |
2007 | gcc_assert ((mask != 0) && ((mask & (mask+1)) == 0)); | |
2008 | ||
3cea8318 | 2009 | int_ptrsize_type = signed_type_for (ptr_type_node); |
fb85abff | 2010 | |
2011 | /* Create expression (mask & (dr_1 || ... || dr_n)) where dr_i is the address | |
2012 | of the first vector of the i'th data reference. */ | |
2013 | ||
f1f41a6c | 2014 | FOR_EACH_VEC_ELT (may_misalign_stmts, i, ref_stmt) |
fb85abff | 2015 | { |
2016 | gimple_seq new_stmt_list = NULL; | |
2017 | tree addr_base; | |
03d37e4e | 2018 | tree addr_tmp_name; |
2019 | tree new_or_tmp_name; | |
42acab1c | 2020 | gimple *addr_stmt, *or_stmt; |
f1b8c740 | 2021 | stmt_vec_info stmt_vinfo = vinfo_for_stmt (ref_stmt); |
2022 | tree vectype = STMT_VINFO_VECTYPE (stmt_vinfo); | |
2023 | bool negative = tree_int_cst_compare | |
2024 | (DR_STEP (STMT_VINFO_DATA_REF (stmt_vinfo)), size_zero_node) < 0; | |
2025 | tree offset = negative | |
80b8a97a | 2026 | ? size_int (-TYPE_VECTOR_SUBPARTS (vectype) + 1) : size_zero_node; |
fb85abff | 2027 | |
2028 | /* create: addr_tmp = (int)(address_of_first_vector) */ | |
2029 | addr_base = | |
2030 | vect_create_addr_base_for_vector_ref (ref_stmt, &new_stmt_list, | |
9e879814 | 2031 | offset); |
fb85abff | 2032 | if (new_stmt_list != NULL) |
2033 | gimple_seq_add_seq (cond_expr_stmt_list, new_stmt_list); | |
2034 | ||
03d37e4e | 2035 | sprintf (tmp_name, "addr2int%d", i); |
2036 | addr_tmp_name = make_temp_ssa_name (int_ptrsize_type, NULL, tmp_name); | |
e9cf809e | 2037 | addr_stmt = gimple_build_assign (addr_tmp_name, NOP_EXPR, addr_base); |
fb85abff | 2038 | gimple_seq_add_stmt (cond_expr_stmt_list, addr_stmt); |
2039 | ||
2040 | /* The addresses are OR together. */ | |
2041 | ||
2042 | if (or_tmp_name != NULL_TREE) | |
2043 | { | |
2044 | /* create: or_tmp = or_tmp | addr_tmp */ | |
03d37e4e | 2045 | sprintf (tmp_name, "orptrs%d", i); |
2046 | new_or_tmp_name = make_temp_ssa_name (int_ptrsize_type, NULL, tmp_name); | |
e9cf809e | 2047 | or_stmt = gimple_build_assign (new_or_tmp_name, BIT_IOR_EXPR, |
2048 | or_tmp_name, addr_tmp_name); | |
fb85abff | 2049 | gimple_seq_add_stmt (cond_expr_stmt_list, or_stmt); |
2050 | or_tmp_name = new_or_tmp_name; | |
2051 | } | |
2052 | else | |
2053 | or_tmp_name = addr_tmp_name; | |
2054 | ||
2055 | } /* end for i */ | |
2056 | ||
2057 | mask_cst = build_int_cst (int_ptrsize_type, mask); | |
2058 | ||
2059 | /* create: and_tmp = or_tmp & mask */ | |
03d37e4e | 2060 | and_tmp_name = make_temp_ssa_name (int_ptrsize_type, NULL, "andmask"); |
fb85abff | 2061 | |
e9cf809e | 2062 | and_stmt = gimple_build_assign (and_tmp_name, BIT_AND_EXPR, |
2063 | or_tmp_name, mask_cst); | |
fb85abff | 2064 | gimple_seq_add_stmt (cond_expr_stmt_list, and_stmt); |
2065 | ||
2066 | /* Make and_tmp the left operand of the conditional test against zero. | |
2067 | if and_tmp has a nonzero bit then some address is unaligned. */ | |
2068 | ptrsize_zero = build_int_cst (int_ptrsize_type, 0); | |
2069 | part_cond_expr = fold_build2 (EQ_EXPR, boolean_type_node, | |
2070 | and_tmp_name, ptrsize_zero); | |
f68a7726 | 2071 | chain_cond_expr (cond_expr, part_cond_expr); |
2072 | } | |
2073 | ||
2074 | /* If LOOP_VINFO_CHECK_UNEQUAL_ADDRS contains <A1, B1>, ..., <An, Bn>, | |
2075 | create a tree representation of: (&A1 != &B1) && ... && (&An != &Bn). | |
2076 | Set *COND_EXPR to a tree that is true when both the original *COND_EXPR | |
2077 | and this new condition are true. Treat a null *COND_EXPR as "true". */ | |
2078 | ||
2079 | static void | |
2080 | vect_create_cond_for_unequal_addrs (loop_vec_info loop_vinfo, tree *cond_expr) | |
2081 | { | |
2082 | vec<vec_object_pair> pairs = LOOP_VINFO_CHECK_UNEQUAL_ADDRS (loop_vinfo); | |
2083 | unsigned int i; | |
2084 | vec_object_pair *pair; | |
2085 | FOR_EACH_VEC_ELT (pairs, i, pair) | |
2086 | { | |
2087 | tree addr1 = build_fold_addr_expr (pair->first); | |
2088 | tree addr2 = build_fold_addr_expr (pair->second); | |
2089 | tree part_cond_expr = fold_build2 (NE_EXPR, boolean_type_node, | |
2090 | addr1, addr2); | |
2091 | chain_cond_expr (cond_expr, part_cond_expr); | |
2092 | } | |
fb85abff | 2093 | } |
2094 | ||
fb85abff | 2095 | /* Function vect_create_cond_for_alias_checks. |
2096 | ||
2097 | Create a conditional expression that represents the run-time checks for | |
2098 | overlapping of address ranges represented by a list of data references | |
2099 | relations passed as input. | |
2100 | ||
2101 | Input: | |
2102 | COND_EXPR - input conditional expression. New conditions will be chained | |
8a7b0f48 | 2103 | with logical AND operation. If it is NULL, then the function |
2104 | is used to return the number of alias checks. | |
fb85abff | 2105 | LOOP_VINFO - field LOOP_VINFO_MAY_ALIAS_STMTS contains the list of ddrs |
2106 | to be checked. | |
2107 | ||
2108 | Output: | |
2109 | COND_EXPR - conditional expression. | |
fb85abff | 2110 | |
8a7b0f48 | 2111 | The returned COND_EXPR is the conditional expression to be used in the if |
fb85abff | 2112 | statement that controls which version of the loop gets executed at runtime. |
2113 | */ | |
2114 | ||
8a7b0f48 | 2115 | void |
90d4c4af | 2116 | vect_create_cond_for_alias_checks (loop_vec_info loop_vinfo, tree * cond_expr) |
fb85abff | 2117 | { |
43d14b66 | 2118 | vec<dr_with_seg_len_pair_t> comp_alias_ddrs = |
8a7b0f48 | 2119 | LOOP_VINFO_COMP_ALIAS_DDRS (loop_vinfo); |
fb85abff | 2120 | |
8a7b0f48 | 2121 | if (comp_alias_ddrs.is_empty ()) |
fb85abff | 2122 | return; |
2123 | ||
49ce332c | 2124 | create_runtime_alias_checks (LOOP_VINFO_LOOP (loop_vinfo), |
2125 | &comp_alias_ddrs, cond_expr); | |
6d8fb6cf | 2126 | if (dump_enabled_p ()) |
b055bc88 | 2127 | dump_printf_loc (MSG_NOTE, vect_location, |
7bd765d4 | 2128 | "created %u versioning for alias checks.\n", |
8a7b0f48 | 2129 | comp_alias_ddrs.length ()); |
fb85abff | 2130 | } |
2131 | ||
2132 | ||
2133 | /* Function vect_loop_versioning. | |
48e1416a | 2134 | |
fb85abff | 2135 | If the loop has data references that may or may not be aligned or/and |
2136 | has data reference relations whose independence was not proven then | |
2137 | two versions of the loop need to be generated, one which is vectorized | |
2138 | and one which isn't. A test is then generated to control which of the | |
2139 | loops is executed. The test checks for the alignment of all of the | |
2140 | data references that may or may not be aligned. An additional | |
2141 | sequence of runtime tests is generated for each pairs of DDRs whose | |
48e1416a | 2142 | independence was not proven. The vectorized version of loop is |
2143 | executed only if both alias and alignment tests are passed. | |
2144 | ||
fb85abff | 2145 | The test generated to check which version of loop is executed |
48e1416a | 2146 | is modified to also check for profitability as indicated by the |
97fe80a6 | 2147 | cost model threshold TH. |
23a3430d | 2148 | |
2149 | The versioning precondition(s) are placed in *COND_EXPR and | |
2afdcbed | 2150 | *COND_EXPR_STMT_LIST. */ |
fb85abff | 2151 | |
2152 | void | |
e7430948 | 2153 | vect_loop_versioning (loop_vec_info loop_vinfo, |
2154 | unsigned int th, bool check_profitability) | |
fb85abff | 2155 | { |
d5e80d93 | 2156 | struct loop *loop = LOOP_VINFO_LOOP (loop_vinfo), *nloop; |
c71d3c24 | 2157 | struct loop *scalar_loop = LOOP_VINFO_SCALAR_LOOP (loop_vinfo); |
fb85abff | 2158 | basic_block condition_bb; |
1a91d914 | 2159 | gphi_iterator gsi; |
2160 | gimple_stmt_iterator cond_exp_gsi; | |
fb85abff | 2161 | basic_block merge_bb; |
2162 | basic_block new_exit_bb; | |
2163 | edge new_exit_e, e; | |
1a91d914 | 2164 | gphi *orig_phi, *new_phi; |
e7430948 | 2165 | tree cond_expr = NULL_TREE; |
2afdcbed | 2166 | gimple_seq cond_expr_stmt_list = NULL; |
fb85abff | 2167 | tree arg; |
ca69b069 | 2168 | profile_probability prob = profile_probability::likely (); |
fb85abff | 2169 | gimple_seq gimplify_stmt_list = NULL; |
b622227e | 2170 | tree scalar_loop_iters = LOOP_VINFO_NITERSM1 (loop_vinfo); |
6ee2edad | 2171 | bool version_align = LOOP_REQUIRES_VERSIONING_FOR_ALIGNMENT (loop_vinfo); |
2172 | bool version_alias = LOOP_REQUIRES_VERSIONING_FOR_ALIAS (loop_vinfo); | |
d5e80d93 | 2173 | bool version_niter = LOOP_REQUIRES_VERSIONING_FOR_NITERS (loop_vinfo); |
fb85abff | 2174 | |
e7430948 | 2175 | if (check_profitability) |
ba12948e | 2176 | cond_expr = fold_build2 (GE_EXPR, boolean_type_node, scalar_loop_iters, |
d5e80d93 | 2177 | build_int_cst (TREE_TYPE (scalar_loop_iters), |
b622227e | 2178 | th - 1)); |
d5e80d93 | 2179 | |
2180 | if (version_niter) | |
2181 | vect_create_cond_for_niters_checks (loop_vinfo, &cond_expr); | |
2182 | ||
2183 | if (cond_expr) | |
2184 | cond_expr = force_gimple_operand_1 (cond_expr, &cond_expr_stmt_list, | |
2185 | is_gimple_condexpr, NULL_TREE); | |
fb85abff | 2186 | |
6ee2edad | 2187 | if (version_align) |
2afdcbed | 2188 | vect_create_cond_for_align_checks (loop_vinfo, &cond_expr, |
2189 | &cond_expr_stmt_list); | |
fb85abff | 2190 | |
6ee2edad | 2191 | if (version_alias) |
f68a7726 | 2192 | { |
2193 | vect_create_cond_for_unequal_addrs (loop_vinfo, &cond_expr); | |
2194 | vect_create_cond_for_alias_checks (loop_vinfo, &cond_expr); | |
2195 | } | |
23a3430d | 2196 | |
2afdcbed | 2197 | cond_expr = force_gimple_operand_1 (cond_expr, &gimplify_stmt_list, |
2198 | is_gimple_condexpr, NULL_TREE); | |
2199 | gimple_seq_add_seq (&cond_expr_stmt_list, gimplify_stmt_list); | |
fb85abff | 2200 | |
2201 | initialize_original_copy_tables (); | |
c71d3c24 | 2202 | if (scalar_loop) |
2203 | { | |
2204 | edge scalar_e; | |
2205 | basic_block preheader, scalar_preheader; | |
2206 | ||
2207 | /* We don't want to scale SCALAR_LOOP's frequencies, we need to | |
2208 | scale LOOP's frequencies instead. */ | |
b6863ffa | 2209 | nloop = loop_version (scalar_loop, cond_expr, &condition_bb, |
ca69b069 | 2210 | prob, prob.invert (), prob, prob.invert (), true); |
2211 | scale_loop_frequencies (loop, prob); | |
c71d3c24 | 2212 | /* CONDITION_BB was created above SCALAR_LOOP's preheader, |
2213 | while we need to move it above LOOP's preheader. */ | |
2214 | e = loop_preheader_edge (loop); | |
2215 | scalar_e = loop_preheader_edge (scalar_loop); | |
2216 | gcc_assert (empty_block_p (e->src) | |
2217 | && single_pred_p (e->src)); | |
2218 | gcc_assert (empty_block_p (scalar_e->src) | |
2219 | && single_pred_p (scalar_e->src)); | |
2220 | gcc_assert (single_pred_p (condition_bb)); | |
2221 | preheader = e->src; | |
2222 | scalar_preheader = scalar_e->src; | |
2223 | scalar_e = find_edge (condition_bb, scalar_preheader); | |
2224 | e = single_pred_edge (preheader); | |
2225 | redirect_edge_and_branch_force (single_pred_edge (condition_bb), | |
2226 | scalar_preheader); | |
2227 | redirect_edge_and_branch_force (scalar_e, preheader); | |
2228 | redirect_edge_and_branch_force (e, condition_bb); | |
2229 | set_immediate_dominator (CDI_DOMINATORS, condition_bb, | |
2230 | single_pred (condition_bb)); | |
2231 | set_immediate_dominator (CDI_DOMINATORS, scalar_preheader, | |
2232 | single_pred (scalar_preheader)); | |
2233 | set_immediate_dominator (CDI_DOMINATORS, preheader, | |
2234 | condition_bb); | |
2235 | } | |
2236 | else | |
d5e80d93 | 2237 | nloop = loop_version (loop, cond_expr, &condition_bb, |
ca69b069 | 2238 | prob, prob.invert (), prob, prob.invert (), true); |
d5e80d93 | 2239 | |
2240 | if (version_niter) | |
2241 | { | |
2242 | /* The versioned loop could be infinite, we need to clear existing | |
2243 | niter information which is copied from the original loop. */ | |
2244 | gcc_assert (loop_constraint_set_p (loop, LOOP_C_FINITE)); | |
2245 | vect_free_loop_info_assumptions (nloop); | |
2246 | /* And set constraint LOOP_C_INFINITE for niter analyzer. */ | |
2247 | loop_constraint_set (loop, LOOP_C_INFINITE); | |
2248 | } | |
6ee2edad | 2249 | |
36f39b2e | 2250 | if (LOCATION_LOCUS (vect_location) != UNKNOWN_LOCATION |
6ee2edad | 2251 | && dump_enabled_p ()) |
2252 | { | |
2253 | if (version_alias) | |
2254 | dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, vect_location, | |
2255 | "loop versioned for vectorization because of " | |
2256 | "possible aliasing\n"); | |
2257 | if (version_align) | |
2258 | dump_printf_loc (MSG_OPTIMIZED_LOCATIONS, vect_location, | |
2259 | "loop versioned for vectorization to enhance " | |
2260 | "alignment\n"); | |
2261 | ||
2262 | } | |
9af5ce0c | 2263 | free_original_copy_tables (); |
fb85abff | 2264 | |
48e1416a | 2265 | /* Loop versioning violates an assumption we try to maintain during |
fb85abff | 2266 | vectorization - that the loop exit block has a single predecessor. |
2267 | After versioning, the exit block of both loop versions is the same | |
2268 | basic block (i.e. it has two predecessors). Just in order to simplify | |
2269 | following transformations in the vectorizer, we fix this situation | |
2270 | here by adding a new (empty) block on the exit-edge of the loop, | |
c71d3c24 | 2271 | with the proper loop-exit phis to maintain loop-closed-form. |
2272 | If loop versioning wasn't done from loop, but scalar_loop instead, | |
2273 | merge_bb will have already just a single successor. */ | |
48e1416a | 2274 | |
fb85abff | 2275 | merge_bb = single_exit (loop)->dest; |
c71d3c24 | 2276 | if (scalar_loop == NULL || EDGE_COUNT (merge_bb->preds) >= 2) |
fb85abff | 2277 | { |
c71d3c24 | 2278 | gcc_assert (EDGE_COUNT (merge_bb->preds) >= 2); |
2279 | new_exit_bb = split_edge (single_exit (loop)); | |
2280 | new_exit_e = single_exit (loop); | |
2281 | e = EDGE_SUCC (new_exit_bb, 0); | |
2282 | ||
2283 | for (gsi = gsi_start_phis (merge_bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
2284 | { | |
2285 | tree new_res; | |
1a91d914 | 2286 | orig_phi = gsi.phi (); |
f9e245b2 | 2287 | new_res = copy_ssa_name (PHI_RESULT (orig_phi)); |
c71d3c24 | 2288 | new_phi = create_phi_node (new_res, new_exit_bb); |
2289 | arg = PHI_ARG_DEF_FROM_EDGE (orig_phi, e); | |
2290 | add_phi_arg (new_phi, arg, new_exit_e, | |
2291 | gimple_phi_arg_location_from_edge (orig_phi, e)); | |
2292 | adjust_phi_and_debug_stmts (orig_phi, e, PHI_RESULT (new_phi)); | |
2293 | } | |
48e1416a | 2294 | } |
fb85abff | 2295 | |
2296 | /* End loop-exit-fixes after versioning. */ | |
2297 | ||
2afdcbed | 2298 | if (cond_expr_stmt_list) |
fb85abff | 2299 | { |
2300 | cond_exp_gsi = gsi_last_bb (condition_bb); | |
2afdcbed | 2301 | gsi_insert_seq_before (&cond_exp_gsi, cond_expr_stmt_list, |
23a3430d | 2302 | GSI_SAME_STMT); |
fb85abff | 2303 | } |
95e19962 | 2304 | update_ssa (TODO_update_ssa); |
fb85abff | 2305 | } |