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402209ff | 1 | /* Natural loop discovery code for GNU compiler. |
99dee823 | 2 | Copyright (C) 2000-2021 Free Software Foundation, Inc. |
402209ff JH |
3 | |
4 | This file is part of GCC. | |
5 | ||
6 | GCC is free software; you can redistribute it and/or modify it under | |
7 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 8 | Software Foundation; either version 3, or (at your option) any later |
402209ff JH |
9 | version. |
10 | ||
11 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
12 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
402209ff JH |
19 | |
20 | #include "config.h" | |
21 | #include "system.h" | |
4977bab6 | 22 | #include "coretypes.h" |
c7131fb2 | 23 | #include "backend.h" |
957060b5 | 24 | #include "rtl.h" |
c7131fb2 AM |
25 | #include "tree.h" |
26 | #include "gimple.h" | |
957060b5 AM |
27 | #include "cfghooks.h" |
28 | #include "gimple-ssa.h" | |
29 | #include "diagnostic-core.h" | |
60393bbc | 30 | #include "cfganal.h" |
3d436d2a | 31 | #include "cfgloop.h" |
5be5c238 | 32 | #include "gimple-iterator.h" |
7ee2468b | 33 | #include "dumpfile.h" |
f470c378 | 34 | |
d73be268 | 35 | static void flow_loops_cfg_dump (FILE *); |
402209ff JH |
36 | \f |
37 | /* Dump loop related CFG information. */ | |
38 | ||
39 | static void | |
d73be268 | 40 | flow_loops_cfg_dump (FILE *file) |
402209ff | 41 | { |
e0082a72 | 42 | basic_block bb; |
402209ff | 43 | |
d73be268 | 44 | if (!file) |
402209ff JH |
45 | return; |
46 | ||
11cd3bed | 47 | FOR_EACH_BB_FN (bb, cfun) |
402209ff JH |
48 | { |
49 | edge succ; | |
628f6a4e | 50 | edge_iterator ei; |
402209ff | 51 | |
e0082a72 | 52 | fprintf (file, ";; %d succs { ", bb->index); |
628f6a4e | 53 | FOR_EACH_EDGE (succ, ei, bb->succs) |
0b17ab2f | 54 | fprintf (file, "%d ", succ->dest->index); |
2ecfd709 | 55 | fprintf (file, "}\n"); |
402209ff | 56 | } |
402209ff JH |
57 | } |
58 | ||
da7d8304 | 59 | /* Return nonzero if the nodes of LOOP are a subset of OUTER. */ |
402209ff | 60 | |
2ecfd709 | 61 | bool |
99b1c316 | 62 | flow_loop_nested_p (const class loop *outer, const class loop *loop) |
402209ff | 63 | { |
9ba025a2 ZD |
64 | unsigned odepth = loop_depth (outer); |
65 | ||
66 | return (loop_depth (loop) > odepth | |
9771b263 | 67 | && (*loop->superloops)[odepth] == outer); |
402209ff JH |
68 | } |
69 | ||
1ad03593 SP |
70 | /* Returns the loop such that LOOP is nested DEPTH (indexed from zero) |
71 | loops within LOOP. */ | |
a7e5372d | 72 | |
99b1c316 MS |
73 | class loop * |
74 | superloop_at_depth (class loop *loop, unsigned depth) | |
a7e5372d | 75 | { |
9ba025a2 ZD |
76 | unsigned ldepth = loop_depth (loop); |
77 | ||
78 | gcc_assert (depth <= ldepth); | |
a7e5372d | 79 | |
9ba025a2 | 80 | if (depth == ldepth) |
a7e5372d ZD |
81 | return loop; |
82 | ||
9771b263 | 83 | return (*loop->superloops)[depth]; |
a7e5372d ZD |
84 | } |
85 | ||
89f8f30f ZD |
86 | /* Returns the list of the latch edges of LOOP. */ |
87 | ||
9771b263 | 88 | static vec<edge> |
99b1c316 | 89 | get_loop_latch_edges (const class loop *loop) |
89f8f30f ZD |
90 | { |
91 | edge_iterator ei; | |
92 | edge e; | |
6e1aa848 | 93 | vec<edge> ret = vNULL; |
89f8f30f ZD |
94 | |
95 | FOR_EACH_EDGE (e, ei, loop->header->preds) | |
96 | { | |
97 | if (dominated_by_p (CDI_DOMINATORS, e->src, loop->header)) | |
9771b263 | 98 | ret.safe_push (e); |
89f8f30f ZD |
99 | } |
100 | ||
101 | return ret; | |
102 | } | |
103 | ||
402209ff JH |
104 | /* Dump the loop information specified by LOOP to the stream FILE |
105 | using auxiliary dump callback function LOOP_DUMP_AUX if non null. */ | |
106 | ||
107 | void | |
99b1c316 MS |
108 | flow_loop_dump (const class loop *loop, FILE *file, |
109 | void (*loop_dump_aux) (const class loop *, FILE *, int), | |
d329e058 | 110 | int verbose) |
402209ff | 111 | { |
2ecfd709 | 112 | basic_block *bbs; |
3d436d2a | 113 | unsigned i; |
9771b263 | 114 | vec<edge> latches; |
89f8f30f | 115 | edge e; |
2ecfd709 | 116 | |
402209ff JH |
117 | if (! loop || ! loop->header) |
118 | return; | |
119 | ||
7490e6c4 | 120 | fprintf (file, ";;\n;; Loop %d\n", loop->num); |
402209ff | 121 | |
89f8f30f ZD |
122 | fprintf (file, ";; header %d, ", loop->header->index); |
123 | if (loop->latch) | |
124 | fprintf (file, "latch %d\n", loop->latch->index); | |
125 | else | |
126 | { | |
127 | fprintf (file, "multiple latches:"); | |
128 | latches = get_loop_latch_edges (loop); | |
9771b263 | 129 | FOR_EACH_VEC_ELT (latches, i, e) |
89f8f30f | 130 | fprintf (file, " %d", e->src->index); |
9771b263 | 131 | latches.release (); |
89f8f30f ZD |
132 | fprintf (file, "\n"); |
133 | } | |
134 | ||
99f8a411 | 135 | fprintf (file, ";; depth %d, outer %ld\n", |
9ba025a2 ZD |
136 | loop_depth (loop), (long) (loop_outer (loop) |
137 | ? loop_outer (loop)->num : -1)); | |
402209ff | 138 | |
199b1891 ML |
139 | if (loop->latch) |
140 | { | |
141 | bool read_profile_p; | |
142 | gcov_type nit = expected_loop_iterations_unbounded (loop, &read_profile_p); | |
143 | if (read_profile_p && !loop->any_estimate) | |
65e009bb JJ |
144 | fprintf (file, ";; profile-based iteration count: %" PRIu64 "\n", |
145 | (uint64_t) nit); | |
199b1891 ML |
146 | } |
147 | ||
2ecfd709 ZD |
148 | fprintf (file, ";; nodes:"); |
149 | bbs = get_loop_body (loop); | |
150 | for (i = 0; i < loop->num_nodes; i++) | |
151 | fprintf (file, " %d", bbs[i]->index); | |
152 | free (bbs); | |
153 | fprintf (file, "\n"); | |
5f0d2358 | 154 | |
402209ff JH |
155 | if (loop_dump_aux) |
156 | loop_dump_aux (loop, file, verbose); | |
157 | } | |
158 | ||
d73be268 | 159 | /* Dump the loop information about loops to the stream FILE, |
402209ff JH |
160 | using auxiliary dump callback function LOOP_DUMP_AUX if non null. */ |
161 | ||
162 | void | |
99b1c316 | 163 | flow_loops_dump (FILE *file, void (*loop_dump_aux) (const class loop *, FILE *, int), int verbose) |
402209ff | 164 | { |
d73be268 | 165 | if (!current_loops || ! file) |
402209ff JH |
166 | return; |
167 | ||
0fc822d0 | 168 | fprintf (file, ";; %d loops found\n", number_of_loops (cfun)); |
2ecfd709 | 169 | |
e41ba804 | 170 | for (auto loop : loops_list (cfun, LI_INCLUDE_ROOT)) |
402209ff | 171 | { |
2ecfd709 | 172 | flow_loop_dump (loop, file, loop_dump_aux, verbose); |
402209ff JH |
173 | } |
174 | ||
175 | if (verbose) | |
d73be268 | 176 | flow_loops_cfg_dump (file); |
402209ff JH |
177 | } |
178 | ||
2ecfd709 | 179 | /* Free data allocated for LOOP. */ |
9e2f83a5 | 180 | |
35b07080 | 181 | void |
99b1c316 | 182 | flow_loop_free (class loop *loop) |
2ecfd709 | 183 | { |
6270df4c ZD |
184 | struct loop_exit *exit, *next; |
185 | ||
9771b263 | 186 | vec_free (loop->superloops); |
6270df4c ZD |
187 | |
188 | /* Break the list of the loop exit records. They will be freed when the | |
189 | corresponding edge is rescanned or removed, and this avoids | |
190 | accessing the (already released) head of the list stored in the | |
191 | loop structure. */ | |
9e2f83a5 | 192 | for (exit = loop->exits->next; exit != loop->exits; exit = next) |
6270df4c ZD |
193 | { |
194 | next = exit->next; | |
195 | exit->next = exit; | |
196 | exit->prev = exit; | |
197 | } | |
9e2f83a5 ZD |
198 | |
199 | ggc_free (loop->exits); | |
200 | ggc_free (loop); | |
2ecfd709 ZD |
201 | } |
202 | ||
402209ff JH |
203 | /* Free all the memory allocated for LOOPS. */ |
204 | ||
205 | void | |
d329e058 | 206 | flow_loops_free (struct loops *loops) |
402209ff | 207 | { |
42fd6772 | 208 | if (loops->larray) |
402209ff | 209 | { |
3d436d2a | 210 | unsigned i; |
42fd6772 | 211 | loop_p loop; |
402209ff JH |
212 | |
213 | /* Free the loop descriptors. */ | |
9771b263 | 214 | FOR_EACH_VEC_SAFE_ELT (loops->larray, i, loop) |
402209ff | 215 | { |
2ecfd709 ZD |
216 | if (!loop) |
217 | continue; | |
218 | ||
219 | flow_loop_free (loop); | |
402209ff | 220 | } |
5f0d2358 | 221 | |
9771b263 | 222 | vec_free (loops->larray); |
402209ff JH |
223 | } |
224 | } | |
225 | ||
2ecfd709 ZD |
226 | /* Find the nodes contained within the LOOP with header HEADER. |
227 | Return the number of nodes within the loop. */ | |
402209ff | 228 | |
2b271002 | 229 | int |
99b1c316 | 230 | flow_loop_nodes_find (basic_block header, class loop *loop) |
402209ff | 231 | { |
6e1aa848 | 232 | vec<basic_block> stack = vNULL; |
2ecfd709 | 233 | int num_nodes = 1; |
89f8f30f ZD |
234 | edge latch; |
235 | edge_iterator latch_ei; | |
402209ff | 236 | |
2ecfd709 | 237 | header->loop_father = loop; |
402209ff | 238 | |
89f8f30f | 239 | FOR_EACH_EDGE (latch, latch_ei, loop->header->preds) |
402209ff | 240 | { |
89f8f30f ZD |
241 | if (latch->src->loop_father == loop |
242 | || !dominated_by_p (CDI_DOMINATORS, latch->src, loop->header)) | |
243 | continue; | |
244 | ||
402209ff | 245 | num_nodes++; |
9771b263 | 246 | stack.safe_push (latch->src); |
89f8f30f | 247 | latch->src->loop_father = loop; |
d329e058 | 248 | |
9771b263 | 249 | while (!stack.is_empty ()) |
402209ff | 250 | { |
2ecfd709 ZD |
251 | basic_block node; |
252 | edge e; | |
628f6a4e | 253 | edge_iterator ei; |
402209ff | 254 | |
9771b263 | 255 | node = stack.pop (); |
d329e058 | 256 | |
628f6a4e | 257 | FOR_EACH_EDGE (e, ei, node->preds) |
402209ff | 258 | { |
2ecfd709 ZD |
259 | basic_block ancestor = e->src; |
260 | ||
89f8f30f | 261 | if (ancestor->loop_father != loop) |
2ecfd709 ZD |
262 | { |
263 | ancestor->loop_father = loop; | |
2ecfd709 | 264 | num_nodes++; |
9771b263 | 265 | stack.safe_push (ancestor); |
2ecfd709 | 266 | } |
402209ff JH |
267 | } |
268 | } | |
269 | } | |
9771b263 | 270 | stack.release (); |
89f8f30f | 271 | |
402209ff JH |
272 | return num_nodes; |
273 | } | |
274 | ||
9ba025a2 ZD |
275 | /* Records the vector of superloops of the loop LOOP, whose immediate |
276 | superloop is FATHER. */ | |
277 | ||
35b07080 | 278 | static void |
99b1c316 | 279 | establish_preds (class loop *loop, class loop *father) |
35b07080 | 280 | { |
9ba025a2 ZD |
281 | loop_p ploop; |
282 | unsigned depth = loop_depth (father) + 1; | |
283 | unsigned i; | |
a310245f | 284 | |
9771b263 DN |
285 | loop->superloops = 0; |
286 | vec_alloc (loop->superloops, depth); | |
287 | FOR_EACH_VEC_SAFE_ELT (father->superloops, i, ploop) | |
288 | loop->superloops->quick_push (ploop); | |
289 | loop->superloops->quick_push (father); | |
35b07080 ZD |
290 | |
291 | for (ploop = loop->inner; ploop; ploop = ploop->next) | |
9ba025a2 | 292 | establish_preds (ploop, loop); |
35b07080 ZD |
293 | } |
294 | ||
2ecfd709 | 295 | /* Add LOOP to the loop hierarchy tree where FATHER is father of the |
35b07080 | 296 | added loop. If LOOP has some children, take care of that their |
1cc521f1 MM |
297 | pred field will be initialized correctly. If AFTER is non-null |
298 | then it's expected it's a pointer into FATHERs inner sibling | |
299 | list and LOOP is added behind AFTER, otherwise it's added in front | |
300 | of FATHERs siblings. */ | |
402209ff | 301 | |
2ecfd709 | 302 | void |
99b1c316 MS |
303 | flow_loop_tree_node_add (class loop *father, class loop *loop, |
304 | class loop *after) | |
402209ff | 305 | { |
1cc521f1 MM |
306 | if (after) |
307 | { | |
308 | loop->next = after->next; | |
309 | after->next = loop; | |
310 | } | |
311 | else | |
312 | { | |
313 | loop->next = father->inner; | |
314 | father->inner = loop; | |
315 | } | |
2ecfd709 | 316 | |
9ba025a2 | 317 | establish_preds (loop, father); |
402209ff JH |
318 | } |
319 | ||
2ecfd709 | 320 | /* Remove LOOP from the loop hierarchy tree. */ |
402209ff | 321 | |
2ecfd709 | 322 | void |
99b1c316 | 323 | flow_loop_tree_node_remove (class loop *loop) |
402209ff | 324 | { |
99b1c316 | 325 | class loop *prev, *father; |
402209ff | 326 | |
9ba025a2 | 327 | father = loop_outer (loop); |
402209ff | 328 | |
2ecfd709 ZD |
329 | /* Remove loop from the list of sons. */ |
330 | if (father->inner == loop) | |
331 | father->inner = loop->next; | |
332 | else | |
333 | { | |
9ba025a2 ZD |
334 | for (prev = father->inner; prev->next != loop; prev = prev->next) |
335 | continue; | |
2ecfd709 ZD |
336 | prev->next = loop->next; |
337 | } | |
402209ff | 338 | |
9771b263 | 339 | loop->superloops = NULL; |
402209ff JH |
340 | } |
341 | ||
6270df4c ZD |
342 | /* Allocates and returns new loop structure. */ |
343 | ||
99b1c316 | 344 | class loop * |
6270df4c ZD |
345 | alloc_loop (void) |
346 | { | |
99b1c316 | 347 | class loop *loop = ggc_cleared_alloc<class loop> (); |
9e2f83a5 | 348 | |
766090c2 | 349 | loop->exits = ggc_cleared_alloc<loop_exit> (); |
9e2f83a5 | 350 | loop->exits->next = loop->exits->prev = loop->exits; |
204b560f | 351 | loop->can_be_parallel = false; |
18767ebc | 352 | loop->constraints = 0; |
807e902e | 353 | loop->nb_iterations_upper_bound = 0; |
200eafbf | 354 | loop->nb_iterations_likely_upper_bound = 0; |
807e902e | 355 | loop->nb_iterations_estimate = 0; |
6270df4c ZD |
356 | return loop; |
357 | } | |
358 | ||
4ed88ee3 ZD |
359 | /* Initializes loops structure LOOPS, reserving place for NUM_LOOPS loops |
360 | (including the root of the loop tree). */ | |
361 | ||
dd366ec3 RB |
362 | void |
363 | init_loops_structure (struct function *fn, | |
364 | struct loops *loops, unsigned num_loops) | |
4ed88ee3 | 365 | { |
99b1c316 | 366 | class loop *root; |
4ed88ee3 ZD |
367 | |
368 | memset (loops, 0, sizeof *loops); | |
9771b263 | 369 | vec_alloc (loops->larray, num_loops); |
4ed88ee3 ZD |
370 | |
371 | /* Dummy loop containing whole function. */ | |
372 | root = alloc_loop (); | |
0cae8d31 | 373 | root->num_nodes = n_basic_blocks_for_fn (fn); |
fefa31b5 DM |
374 | root->latch = EXIT_BLOCK_PTR_FOR_FN (fn); |
375 | root->header = ENTRY_BLOCK_PTR_FOR_FN (fn); | |
376 | ENTRY_BLOCK_PTR_FOR_FN (fn)->loop_father = root; | |
377 | EXIT_BLOCK_PTR_FOR_FN (fn)->loop_father = root; | |
4ed88ee3 | 378 | |
9771b263 | 379 | loops->larray->quick_push (root); |
4ed88ee3 ZD |
380 | loops->tree_root = root; |
381 | } | |
382 | ||
0375167b RB |
383 | /* Returns whether HEADER is a loop header. */ |
384 | ||
385 | bool | |
386 | bb_loop_header_p (basic_block header) | |
387 | { | |
388 | edge_iterator ei; | |
389 | edge e; | |
390 | ||
391 | /* If we have an abnormal predecessor, do not consider the | |
392 | loop (not worth the problems). */ | |
393 | if (bb_has_abnormal_pred (header)) | |
394 | return false; | |
395 | ||
396 | /* Look for back edges where a predecessor is dominated | |
397 | by this block. A natural loop has a single entry | |
398 | node (header) that dominates all the nodes in the | |
399 | loop. It also has single back edge to the header | |
400 | from a latch node. */ | |
401 | FOR_EACH_EDGE (e, ei, header->preds) | |
402 | { | |
403 | basic_block latch = e->src; | |
fefa31b5 | 404 | if (latch != ENTRY_BLOCK_PTR_FOR_FN (cfun) |
0375167b RB |
405 | && dominated_by_p (CDI_DOMINATORS, latch, header)) |
406 | return true; | |
407 | } | |
408 | ||
409 | return false; | |
410 | } | |
411 | ||
5f0d2358 | 412 | /* Find all the natural loops in the function and save in LOOPS structure and |
391886c8 | 413 | recalculate loop_father information in basic block structures. |
0375167b RB |
414 | If LOOPS is non-NULL then the loop structures for already recorded loops |
415 | will be re-used and their number will not change. We assume that no | |
416 | stale loops exist in LOOPS. | |
417 | When LOOPS is NULL it is allocated and re-built from scratch. | |
418 | Return the built LOOPS structure. */ | |
402209ff | 419 | |
0375167b | 420 | struct loops * |
70388d94 | 421 | flow_loops_find (struct loops *loops) |
402209ff | 422 | { |
0375167b | 423 | bool from_scratch = (loops == NULL); |
402209ff | 424 | int *rc_order; |
0375167b RB |
425 | int b; |
426 | unsigned i; | |
402209ff | 427 | |
4ed88ee3 ZD |
428 | /* Ensure that the dominators are computed. */ |
429 | calculate_dominance_info (CDI_DOMINATORS); | |
402209ff | 430 | |
0375167b | 431 | if (!loops) |
4ed88ee3 | 432 | { |
766090c2 | 433 | loops = ggc_cleared_alloc<struct loops> (); |
dd366ec3 | 434 | init_loops_structure (cfun, loops, 1); |
4ed88ee3 | 435 | } |
402209ff | 436 | |
0375167b RB |
437 | /* Ensure that loop exits were released. */ |
438 | gcc_assert (loops->exits == NULL); | |
402209ff | 439 | |
0375167b RB |
440 | /* Taking care of this degenerate case makes the rest of |
441 | this code simpler. */ | |
0cae8d31 | 442 | if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS) |
0375167b | 443 | return loops; |
2ecfd709 | 444 | |
0375167b | 445 | /* The root loop node contains all basic-blocks. */ |
0cae8d31 | 446 | loops->tree_root->num_nodes = n_basic_blocks_for_fn (cfun); |
d329e058 | 447 | |
0375167b RB |
448 | /* Compute depth first search order of the CFG so that outer |
449 | natural loops will be found before inner natural loops. */ | |
0cae8d31 | 450 | rc_order = XNEWVEC (int, n_basic_blocks_for_fn (cfun)); |
0375167b | 451 | pre_and_rev_post_order_compute (NULL, rc_order, false); |
16f2b86a | 452 | |
0375167b RB |
453 | /* Gather all loop headers in reverse completion order and allocate |
454 | loop structures for loops that are not already present. */ | |
ef062b13 | 455 | auto_vec<loop_p> larray (loops->larray->length ()); |
0cae8d31 | 456 | for (b = 0; b < n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS; b++) |
0375167b | 457 | { |
06e28de2 | 458 | basic_block header = BASIC_BLOCK_FOR_FN (cfun, rc_order[b]); |
0375167b | 459 | if (bb_loop_header_p (header)) |
402209ff | 460 | { |
99b1c316 | 461 | class loop *loop; |
2ecfd709 | 462 | |
0375167b RB |
463 | /* The current active loop tree has valid loop-fathers for |
464 | header blocks. */ | |
465 | if (!from_scratch | |
466 | && header->loop_father->header == header) | |
2ecfd709 | 467 | { |
0375167b RB |
468 | loop = header->loop_father; |
469 | /* If we found an existing loop remove it from the | |
470 | loop tree. It is going to be inserted again | |
471 | below. */ | |
472 | flow_loop_tree_node_remove (loop); | |
2ecfd709 | 473 | } |
0375167b RB |
474 | else |
475 | { | |
476 | /* Otherwise allocate a new loop structure for the loop. */ | |
477 | loop = alloc_loop (); | |
478 | /* ??? We could re-use unused loop slots here. */ | |
479 | loop->num = loops->larray->length (); | |
480 | vec_safe_push (loops->larray, loop); | |
481 | loop->header = header; | |
482 | ||
483 | if (!from_scratch | |
484 | && dump_file && (dump_flags & TDF_DETAILS)) | |
485 | fprintf (dump_file, "flow_loops_find: discovered new " | |
486 | "loop %d with header %d\n", | |
487 | loop->num, header->index); | |
488 | } | |
6aaf596b RB |
489 | /* Reset latch, we recompute it below. */ |
490 | loop->latch = NULL; | |
0375167b | 491 | larray.safe_push (loop); |
402209ff | 492 | } |
402209ff | 493 | |
0375167b RB |
494 | /* Make blocks part of the loop root node at start. */ |
495 | header->loop_father = loops->tree_root; | |
496 | } | |
2ecfd709 | 497 | |
0375167b | 498 | free (rc_order); |
2ecfd709 | 499 | |
0375167b RB |
500 | /* Now iterate over the loops found, insert them into the loop tree |
501 | and assign basic-block ownership. */ | |
502 | for (i = 0; i < larray.length (); ++i) | |
402209ff | 503 | { |
99b1c316 | 504 | class loop *loop = larray[i]; |
0375167b | 505 | basic_block header = loop->header; |
09c5c12e TV |
506 | edge_iterator ei; |
507 | edge e; | |
402209ff | 508 | |
0375167b RB |
509 | flow_loop_tree_node_add (header->loop_father, loop); |
510 | loop->num_nodes = flow_loop_nodes_find (loop->header, loop); | |
09c5c12e TV |
511 | |
512 | /* Look for the latch for this header block, if it has just a | |
513 | single one. */ | |
514 | FOR_EACH_EDGE (e, ei, header->preds) | |
515 | { | |
516 | basic_block latch = e->src; | |
517 | ||
518 | if (flow_bb_inside_loop_p (loop, latch)) | |
519 | { | |
520 | if (loop->latch != NULL) | |
521 | { | |
522 | /* More than one latch edge. */ | |
523 | loop->latch = NULL; | |
524 | break; | |
525 | } | |
526 | loop->latch = latch; | |
527 | } | |
528 | } | |
2ecfd709 | 529 | } |
3d436d2a | 530 | |
0375167b | 531 | return loops; |
402209ff JH |
532 | } |
533 | ||
26993e95 RB |
534 | /* qsort helper for sort_sibling_loops. */ |
535 | ||
536 | static int *sort_sibling_loops_cmp_rpo; | |
537 | static int | |
538 | sort_sibling_loops_cmp (const void *la_, const void *lb_) | |
539 | { | |
99b1c316 MS |
540 | const class loop *la = *(const class loop * const *)la_; |
541 | const class loop *lb = *(const class loop * const *)lb_; | |
26993e95 RB |
542 | return (sort_sibling_loops_cmp_rpo[la->header->index] |
543 | - sort_sibling_loops_cmp_rpo[lb->header->index]); | |
544 | } | |
545 | ||
546 | /* Sort sibling loops in RPO order. */ | |
547 | ||
548 | void | |
549 | sort_sibling_loops (function *fn) | |
550 | { | |
551 | /* Match flow_loops_find in the order we sort sibling loops. */ | |
552 | sort_sibling_loops_cmp_rpo = XNEWVEC (int, last_basic_block_for_fn (cfun)); | |
553 | int *rc_order = XNEWVEC (int, n_basic_blocks_for_fn (cfun)); | |
554 | pre_and_rev_post_order_compute_fn (fn, NULL, rc_order, false); | |
555 | for (int i = 0; i < n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS; ++i) | |
556 | sort_sibling_loops_cmp_rpo[rc_order[i]] = i; | |
557 | free (rc_order); | |
558 | ||
559 | auto_vec<loop_p, 3> siblings; | |
e41ba804 | 560 | for (auto loop : loops_list (fn, LI_INCLUDE_ROOT)) |
26993e95 RB |
561 | if (loop->inner && loop->inner->next) |
562 | { | |
563 | loop_p sibling = loop->inner; | |
564 | do | |
565 | { | |
566 | siblings.safe_push (sibling); | |
567 | sibling = sibling->next; | |
568 | } | |
569 | while (sibling); | |
570 | siblings.qsort (sort_sibling_loops_cmp); | |
571 | loop_p *siblingp = &loop->inner; | |
572 | for (unsigned i = 0; i < siblings.length (); ++i) | |
573 | { | |
574 | *siblingp = siblings[i]; | |
575 | siblingp = &(*siblingp)->next; | |
576 | } | |
577 | *siblingp = NULL; | |
578 | siblings.truncate (0); | |
579 | } | |
580 | ||
581 | free (sort_sibling_loops_cmp_rpo); | |
582 | sort_sibling_loops_cmp_rpo = NULL; | |
583 | } | |
584 | ||
89f8f30f ZD |
585 | /* Ratio of frequencies of edges so that one of more latch edges is |
586 | considered to belong to inner loop with same header. */ | |
587 | #define HEAVY_EDGE_RATIO 8 | |
588 | ||
589 | /* Minimum number of samples for that we apply | |
590 | find_subloop_latch_edge_by_profile heuristics. */ | |
591 | #define HEAVY_EDGE_MIN_SAMPLES 10 | |
592 | ||
593 | /* If the profile info is available, finds an edge in LATCHES that much more | |
594 | frequent than the remaining edges. Returns such an edge, or NULL if we do | |
595 | not find one. | |
596 | ||
597 | We do not use guessed profile here, only the measured one. The guessed | |
598 | profile is usually too flat and unreliable for this (and it is mostly based | |
599 | on the loop structure of the program, so it does not make much sense to | |
600 | derive the loop structure from it). */ | |
b8698a0f | 601 | |
89f8f30f | 602 | static edge |
9771b263 | 603 | find_subloop_latch_edge_by_profile (vec<edge> latches) |
89f8f30f ZD |
604 | { |
605 | unsigned i; | |
606 | edge e, me = NULL; | |
3995f3a2 | 607 | profile_count mcount = profile_count::zero (), tcount = profile_count::zero (); |
89f8f30f | 608 | |
9771b263 | 609 | FOR_EACH_VEC_ELT (latches, i, e) |
89f8f30f | 610 | { |
ef30ab83 | 611 | if (e->count ()> mcount) |
89f8f30f ZD |
612 | { |
613 | me = e; | |
ef30ab83 | 614 | mcount = e->count(); |
89f8f30f | 615 | } |
ef30ab83 | 616 | tcount += e->count(); |
89f8f30f ZD |
617 | } |
618 | ||
e7a74006 | 619 | if (!tcount.initialized_p () || !(tcount.ipa () > HEAVY_EDGE_MIN_SAMPLES) |
3995f3a2 | 620 | || (tcount - mcount).apply_scale (HEAVY_EDGE_RATIO, 1) > tcount) |
89f8f30f ZD |
621 | return NULL; |
622 | ||
623 | if (dump_file) | |
624 | fprintf (dump_file, | |
625 | "Found latch edge %d -> %d using profile information.\n", | |
626 | me->src->index, me->dest->index); | |
627 | return me; | |
628 | } | |
629 | ||
630 | /* Among LATCHES, guesses a latch edge of LOOP corresponding to subloop, based | |
631 | on the structure of induction variables. Returns this edge, or NULL if we | |
632 | do not find any. | |
633 | ||
634 | We are quite conservative, and look just for an obvious simple innermost | |
635 | loop (which is the case where we would lose the most performance by not | |
636 | disambiguating the loop). More precisely, we look for the following | |
637 | situation: The source of the chosen latch edge dominates sources of all | |
638 | the other latch edges. Additionally, the header does not contain a phi node | |
639 | such that the argument from the chosen edge is equal to the argument from | |
640 | another edge. */ | |
641 | ||
642 | static edge | |
99b1c316 | 643 | find_subloop_latch_edge_by_ivs (class loop *loop ATTRIBUTE_UNUSED, vec<edge> latches) |
89f8f30f | 644 | { |
9771b263 | 645 | edge e, latch = latches[0]; |
89f8f30f | 646 | unsigned i; |
538dd0b7 DM |
647 | gphi *phi; |
648 | gphi_iterator psi; | |
726a989a | 649 | tree lop; |
89f8f30f ZD |
650 | basic_block bb; |
651 | ||
652 | /* Find the candidate for the latch edge. */ | |
9771b263 | 653 | for (i = 1; latches.iterate (i, &e); i++) |
89f8f30f ZD |
654 | if (dominated_by_p (CDI_DOMINATORS, latch->src, e->src)) |
655 | latch = e; | |
656 | ||
657 | /* Verify that it dominates all the latch edges. */ | |
9771b263 | 658 | FOR_EACH_VEC_ELT (latches, i, e) |
89f8f30f ZD |
659 | if (!dominated_by_p (CDI_DOMINATORS, e->src, latch->src)) |
660 | return NULL; | |
661 | ||
662 | /* Check for a phi node that would deny that this is a latch edge of | |
663 | a subloop. */ | |
726a989a | 664 | for (psi = gsi_start_phis (loop->header); !gsi_end_p (psi); gsi_next (&psi)) |
89f8f30f | 665 | { |
538dd0b7 | 666 | phi = psi.phi (); |
89f8f30f ZD |
667 | lop = PHI_ARG_DEF_FROM_EDGE (phi, latch); |
668 | ||
669 | /* Ignore the values that are not changed inside the subloop. */ | |
670 | if (TREE_CODE (lop) != SSA_NAME | |
671 | || SSA_NAME_DEF_STMT (lop) == phi) | |
672 | continue; | |
726a989a | 673 | bb = gimple_bb (SSA_NAME_DEF_STMT (lop)); |
89f8f30f ZD |
674 | if (!bb || !flow_bb_inside_loop_p (loop, bb)) |
675 | continue; | |
676 | ||
9771b263 | 677 | FOR_EACH_VEC_ELT (latches, i, e) |
89f8f30f ZD |
678 | if (e != latch |
679 | && PHI_ARG_DEF_FROM_EDGE (phi, e) == lop) | |
680 | return NULL; | |
681 | } | |
682 | ||
683 | if (dump_file) | |
684 | fprintf (dump_file, | |
685 | "Found latch edge %d -> %d using iv structure.\n", | |
686 | latch->src->index, latch->dest->index); | |
687 | return latch; | |
688 | } | |
689 | ||
690 | /* If we can determine that one of the several latch edges of LOOP behaves | |
691 | as a latch edge of a separate subloop, returns this edge. Otherwise | |
692 | returns NULL. */ | |
693 | ||
694 | static edge | |
99b1c316 | 695 | find_subloop_latch_edge (class loop *loop) |
89f8f30f | 696 | { |
9771b263 | 697 | vec<edge> latches = get_loop_latch_edges (loop); |
89f8f30f ZD |
698 | edge latch = NULL; |
699 | ||
9771b263 | 700 | if (latches.length () > 1) |
89f8f30f ZD |
701 | { |
702 | latch = find_subloop_latch_edge_by_profile (latches); | |
703 | ||
704 | if (!latch | |
705 | /* We consider ivs to guess the latch edge only in SSA. Perhaps we | |
706 | should use cfghook for this, but it is hard to imagine it would | |
707 | be useful elsewhere. */ | |
708 | && current_ir_type () == IR_GIMPLE) | |
709 | latch = find_subloop_latch_edge_by_ivs (loop, latches); | |
710 | } | |
711 | ||
9771b263 | 712 | latches.release (); |
89f8f30f ZD |
713 | return latch; |
714 | } | |
715 | ||
716 | /* Callback for make_forwarder_block. Returns true if the edge E is marked | |
717 | in the set MFB_REIS_SET. */ | |
718 | ||
6e2830c3 | 719 | static hash_set<edge> *mfb_reis_set; |
89f8f30f ZD |
720 | static bool |
721 | mfb_redirect_edges_in_set (edge e) | |
722 | { | |
6e2830c3 | 723 | return mfb_reis_set->contains (e); |
89f8f30f ZD |
724 | } |
725 | ||
726 | /* Creates a subloop of LOOP with latch edge LATCH. */ | |
727 | ||
728 | static void | |
99b1c316 | 729 | form_subloop (class loop *loop, edge latch) |
89f8f30f ZD |
730 | { |
731 | edge_iterator ei; | |
732 | edge e, new_entry; | |
99b1c316 | 733 | class loop *new_loop; |
b8698a0f | 734 | |
6e2830c3 | 735 | mfb_reis_set = new hash_set<edge>; |
89f8f30f ZD |
736 | FOR_EACH_EDGE (e, ei, loop->header->preds) |
737 | { | |
738 | if (e != latch) | |
6e2830c3 | 739 | mfb_reis_set->add (e); |
89f8f30f ZD |
740 | } |
741 | new_entry = make_forwarder_block (loop->header, mfb_redirect_edges_in_set, | |
742 | NULL); | |
6e2830c3 | 743 | delete mfb_reis_set; |
89f8f30f ZD |
744 | |
745 | loop->header = new_entry->src; | |
746 | ||
747 | /* Find the blocks and subloops that belong to the new loop, and add it to | |
748 | the appropriate place in the loop tree. */ | |
749 | new_loop = alloc_loop (); | |
750 | new_loop->header = new_entry->dest; | |
751 | new_loop->latch = latch->src; | |
752 | add_loop (new_loop, loop); | |
753 | } | |
754 | ||
755 | /* Make all the latch edges of LOOP to go to a single forwarder block -- | |
756 | a new latch of LOOP. */ | |
757 | ||
758 | static void | |
99b1c316 | 759 | merge_latch_edges (class loop *loop) |
89f8f30f | 760 | { |
9771b263 | 761 | vec<edge> latches = get_loop_latch_edges (loop); |
89f8f30f ZD |
762 | edge latch, e; |
763 | unsigned i; | |
764 | ||
9771b263 | 765 | gcc_assert (latches.length () > 0); |
89f8f30f | 766 | |
9771b263 DN |
767 | if (latches.length () == 1) |
768 | loop->latch = latches[0]->src; | |
89f8f30f ZD |
769 | else |
770 | { | |
771 | if (dump_file) | |
772 | fprintf (dump_file, "Merged latch edges of loop %d\n", loop->num); | |
773 | ||
6e2830c3 | 774 | mfb_reis_set = new hash_set<edge>; |
9771b263 | 775 | FOR_EACH_VEC_ELT (latches, i, e) |
6e2830c3 | 776 | mfb_reis_set->add (e); |
89f8f30f ZD |
777 | latch = make_forwarder_block (loop->header, mfb_redirect_edges_in_set, |
778 | NULL); | |
6e2830c3 | 779 | delete mfb_reis_set; |
89f8f30f ZD |
780 | |
781 | loop->header = latch->dest; | |
782 | loop->latch = latch->src; | |
783 | } | |
784 | ||
9771b263 | 785 | latches.release (); |
89f8f30f ZD |
786 | } |
787 | ||
788 | /* LOOP may have several latch edges. Transform it into (possibly several) | |
789 | loops with single latch edge. */ | |
790 | ||
791 | static void | |
99b1c316 | 792 | disambiguate_multiple_latches (class loop *loop) |
89f8f30f ZD |
793 | { |
794 | edge e; | |
795 | ||
ea2c620c | 796 | /* We eliminate the multiple latches by splitting the header to the forwarder |
89f8f30f ZD |
797 | block F and the rest R, and redirecting the edges. There are two cases: |
798 | ||
799 | 1) If there is a latch edge E that corresponds to a subloop (we guess | |
800 | that based on profile -- if it is taken much more often than the | |
801 | remaining edges; and on trees, using the information about induction | |
802 | variables of the loops), we redirect E to R, all the remaining edges to | |
803 | F, then rescan the loops and try again for the outer loop. | |
804 | 2) If there is no such edge, we redirect all latch edges to F, and the | |
805 | entry edges to R, thus making F the single latch of the loop. */ | |
806 | ||
807 | if (dump_file) | |
808 | fprintf (dump_file, "Disambiguating loop %d with multiple latches\n", | |
809 | loop->num); | |
810 | ||
811 | /* During latch merging, we may need to redirect the entry edges to a new | |
812 | block. This would cause problems if the entry edge was the one from the | |
813 | entry block. To avoid having to handle this case specially, split | |
814 | such entry edge. */ | |
fefa31b5 | 815 | e = find_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun), loop->header); |
89f8f30f ZD |
816 | if (e) |
817 | split_edge (e); | |
818 | ||
819 | while (1) | |
820 | { | |
821 | e = find_subloop_latch_edge (loop); | |
822 | if (!e) | |
823 | break; | |
824 | ||
825 | form_subloop (loop, e); | |
826 | } | |
827 | ||
828 | merge_latch_edges (loop); | |
829 | } | |
830 | ||
831 | /* Split loops with multiple latch edges. */ | |
832 | ||
833 | void | |
834 | disambiguate_loops_with_multiple_latches (void) | |
835 | { | |
e41ba804 | 836 | for (auto loop : loops_list (cfun, 0)) |
89f8f30f ZD |
837 | { |
838 | if (!loop->latch) | |
839 | disambiguate_multiple_latches (loop); | |
840 | } | |
841 | } | |
842 | ||
da7d8304 | 843 | /* Return nonzero if basic block BB belongs to LOOP. */ |
2ecfd709 | 844 | bool |
99b1c316 | 845 | flow_bb_inside_loop_p (const class loop *loop, const_basic_block bb) |
2ecfd709 | 846 | { |
99b1c316 | 847 | class loop *source_loop; |
2ecfd709 | 848 | |
fefa31b5 DM |
849 | if (bb == ENTRY_BLOCK_PTR_FOR_FN (cfun) |
850 | || bb == EXIT_BLOCK_PTR_FOR_FN (cfun)) | |
2ecfd709 ZD |
851 | return 0; |
852 | ||
853 | source_loop = bb->loop_father; | |
854 | return loop == source_loop || flow_loop_nested_p (loop, source_loop); | |
855 | } | |
856 | ||
89f8f30f | 857 | /* Enumeration predicate for get_loop_body_with_size. */ |
2ecfd709 | 858 | static bool |
ed7a4b4b | 859 | glb_enum_p (const_basic_block bb, const void *glb_loop) |
2ecfd709 | 860 | { |
99b1c316 | 861 | const class loop *const loop = (const class loop *) glb_loop; |
89f8f30f ZD |
862 | return (bb != loop->header |
863 | && dominated_by_p (CDI_DOMINATORS, bb, loop->header)); | |
864 | } | |
865 | ||
866 | /* Gets basic blocks of a LOOP. Header is the 0-th block, rest is in dfs | |
867 | order against direction of edges from latch. Specially, if | |
868 | header != latch, latch is the 1-st block. LOOP cannot be the fake | |
869 | loop tree root, and its size must be at most MAX_SIZE. The blocks | |
870 | in the LOOP body are stored to BODY, and the size of the LOOP is | |
871 | returned. */ | |
872 | ||
873 | unsigned | |
99b1c316 | 874 | get_loop_body_with_size (const class loop *loop, basic_block *body, |
89f8f30f ZD |
875 | unsigned max_size) |
876 | { | |
877 | return dfs_enumerate_from (loop->header, 1, glb_enum_p, | |
ed7a4b4b | 878 | body, max_size, loop); |
2ecfd709 ZD |
879 | } |
880 | ||
8d28e87d ZD |
881 | /* Gets basic blocks of a LOOP. Header is the 0-th block, rest is in dfs |
882 | order against direction of edges from latch. Specially, if | |
883 | header != latch, latch is the 1-st block. */ | |
89f8f30f | 884 | |
2ecfd709 | 885 | basic_block * |
99b1c316 | 886 | get_loop_body (const class loop *loop) |
2ecfd709 | 887 | { |
89f8f30f | 888 | basic_block *body, bb; |
3d436d2a | 889 | unsigned tv = 0; |
2ecfd709 | 890 | |
341c100f | 891 | gcc_assert (loop->num_nodes); |
2ecfd709 | 892 | |
c302207e | 893 | body = XNEWVEC (basic_block, loop->num_nodes); |
2ecfd709 | 894 | |
fefa31b5 | 895 | if (loop->latch == EXIT_BLOCK_PTR_FOR_FN (cfun)) |
2ecfd709 | 896 | { |
89f8f30f ZD |
897 | /* There may be blocks unreachable from EXIT_BLOCK, hence we need to |
898 | special-case the fake loop that contains the whole function. */ | |
0cae8d31 | 899 | gcc_assert (loop->num_nodes == (unsigned) n_basic_blocks_for_fn (cfun)); |
89f8f30f | 900 | body[tv++] = loop->header; |
fefa31b5 | 901 | body[tv++] = EXIT_BLOCK_PTR_FOR_FN (cfun); |
11cd3bed | 902 | FOR_EACH_BB_FN (bb, cfun) |
89f8f30f | 903 | body[tv++] = bb; |
2ecfd709 | 904 | } |
89f8f30f ZD |
905 | else |
906 | tv = get_loop_body_with_size (loop, body, loop->num_nodes); | |
2ecfd709 | 907 | |
341c100f | 908 | gcc_assert (tv == loop->num_nodes); |
89f8f30f | 909 | return body; |
2ecfd709 ZD |
910 | } |
911 | ||
50654f6c ZD |
912 | /* Fills dominance descendants inside LOOP of the basic block BB into |
913 | array TOVISIT from index *TV. */ | |
914 | ||
915 | static void | |
99b1c316 | 916 | fill_sons_in_loop (const class loop *loop, basic_block bb, |
50654f6c ZD |
917 | basic_block *tovisit, int *tv) |
918 | { | |
919 | basic_block son, postpone = NULL; | |
920 | ||
921 | tovisit[(*tv)++] = bb; | |
922 | for (son = first_dom_son (CDI_DOMINATORS, bb); | |
923 | son; | |
924 | son = next_dom_son (CDI_DOMINATORS, son)) | |
925 | { | |
926 | if (!flow_bb_inside_loop_p (loop, son)) | |
927 | continue; | |
928 | ||
929 | if (dominated_by_p (CDI_DOMINATORS, loop->latch, son)) | |
930 | { | |
931 | postpone = son; | |
932 | continue; | |
933 | } | |
934 | fill_sons_in_loop (loop, son, tovisit, tv); | |
935 | } | |
936 | ||
937 | if (postpone) | |
938 | fill_sons_in_loop (loop, postpone, tovisit, tv); | |
939 | } | |
940 | ||
941 | /* Gets body of a LOOP (that must be different from the outermost loop) | |
942 | sorted by dominance relation. Additionally, if a basic block s dominates | |
943 | the latch, then only blocks dominated by s are be after it. */ | |
944 | ||
945 | basic_block * | |
99b1c316 | 946 | get_loop_body_in_dom_order (const class loop *loop) |
50654f6c ZD |
947 | { |
948 | basic_block *tovisit; | |
949 | int tv; | |
950 | ||
341c100f | 951 | gcc_assert (loop->num_nodes); |
50654f6c | 952 | |
c302207e | 953 | tovisit = XNEWVEC (basic_block, loop->num_nodes); |
50654f6c | 954 | |
fefa31b5 | 955 | gcc_assert (loop->latch != EXIT_BLOCK_PTR_FOR_FN (cfun)); |
50654f6c ZD |
956 | |
957 | tv = 0; | |
958 | fill_sons_in_loop (loop, loop->header, tovisit, &tv); | |
959 | ||
341c100f | 960 | gcc_assert (tv == (int) loop->num_nodes); |
50654f6c ZD |
961 | |
962 | return tovisit; | |
963 | } | |
964 | ||
e855c69d AB |
965 | /* Gets body of a LOOP sorted via provided BB_COMPARATOR. */ |
966 | ||
967 | basic_block * | |
99b1c316 | 968 | get_loop_body_in_custom_order (const class loop *loop, |
e855c69d AB |
969 | int (*bb_comparator) (const void *, const void *)) |
970 | { | |
971 | basic_block *bbs = get_loop_body (loop); | |
972 | ||
973 | qsort (bbs, loop->num_nodes, sizeof (basic_block), bb_comparator); | |
974 | ||
975 | return bbs; | |
976 | } | |
977 | ||
eef99cd9 GB |
978 | /* Same as above, but use gcc_sort_r instead of qsort. */ |
979 | ||
980 | basic_block * | |
981 | get_loop_body_in_custom_order (const class loop *loop, void *data, | |
982 | int (*bb_comparator) (const void *, const void *, void *)) | |
983 | { | |
984 | basic_block *bbs = get_loop_body (loop); | |
985 | ||
986 | gcc_sort_r (bbs, loop->num_nodes, sizeof (basic_block), bb_comparator, data); | |
987 | ||
988 | return bbs; | |
989 | } | |
990 | ||
40923b20 DP |
991 | /* Get body of a LOOP in breadth first sort order. */ |
992 | ||
993 | basic_block * | |
99b1c316 | 994 | get_loop_body_in_bfs_order (const class loop *loop) |
40923b20 DP |
995 | { |
996 | basic_block *blocks; | |
997 | basic_block bb; | |
895548a5 KT |
998 | unsigned int i = 1; |
999 | unsigned int vc = 0; | |
40923b20 | 1000 | |
341c100f | 1001 | gcc_assert (loop->num_nodes); |
fefa31b5 | 1002 | gcc_assert (loop->latch != EXIT_BLOCK_PTR_FOR_FN (cfun)); |
40923b20 | 1003 | |
c302207e | 1004 | blocks = XNEWVEC (basic_block, loop->num_nodes); |
0e3de1d4 | 1005 | auto_bitmap visited; |
895548a5 KT |
1006 | blocks[0] = loop->header; |
1007 | bitmap_set_bit (visited, loop->header->index); | |
40923b20 DP |
1008 | while (i < loop->num_nodes) |
1009 | { | |
1010 | edge e; | |
628f6a4e | 1011 | edge_iterator ei; |
895548a5 KT |
1012 | gcc_assert (i > vc); |
1013 | bb = blocks[vc++]; | |
c22cacf3 | 1014 | |
628f6a4e | 1015 | FOR_EACH_EDGE (e, ei, bb->succs) |
c22cacf3 MS |
1016 | { |
1017 | if (flow_bb_inside_loop_p (loop, e->dest)) | |
1018 | { | |
895548a5 | 1019 | /* This bb is now visited. */ |
fcaa4ca4 NF |
1020 | if (bitmap_set_bit (visited, e->dest->index)) |
1021 | blocks[i++] = e->dest; | |
c22cacf3 MS |
1022 | } |
1023 | } | |
40923b20 | 1024 | } |
c22cacf3 | 1025 | |
40923b20 DP |
1026 | return blocks; |
1027 | } | |
1028 | ||
6270df4c ZD |
1029 | /* Hash function for struct loop_exit. */ |
1030 | ||
2a22f99c TS |
1031 | hashval_t |
1032 | loop_exit_hasher::hash (loop_exit *exit) | |
6270df4c | 1033 | { |
6270df4c ZD |
1034 | return htab_hash_pointer (exit->e); |
1035 | } | |
1036 | ||
1037 | /* Equality function for struct loop_exit. Compares with edge. */ | |
1038 | ||
2a22f99c TS |
1039 | bool |
1040 | loop_exit_hasher::equal (loop_exit *exit, edge e) | |
6270df4c | 1041 | { |
6270df4c ZD |
1042 | return exit->e == e; |
1043 | } | |
1044 | ||
1045 | /* Frees the list of loop exit descriptions EX. */ | |
1046 | ||
2a22f99c TS |
1047 | void |
1048 | loop_exit_hasher::remove (loop_exit *exit) | |
6270df4c | 1049 | { |
2a22f99c | 1050 | loop_exit *next; |
6270df4c ZD |
1051 | for (; exit; exit = next) |
1052 | { | |
1053 | next = exit->next_e; | |
b8698a0f | 1054 | |
6270df4c ZD |
1055 | exit->next->prev = exit->prev; |
1056 | exit->prev->next = exit->next; | |
1057 | ||
9e2f83a5 | 1058 | ggc_free (exit); |
6270df4c ZD |
1059 | } |
1060 | } | |
1061 | ||
1062 | /* Returns the list of records for E as an exit of a loop. */ | |
1063 | ||
1064 | static struct loop_exit * | |
1065 | get_exit_descriptions (edge e) | |
1066 | { | |
2a22f99c | 1067 | return current_loops->exits->find_with_hash (e, htab_hash_pointer (e)); |
6270df4c ZD |
1068 | } |
1069 | ||
1070 | /* Updates the lists of loop exits in that E appears. | |
1071 | If REMOVED is true, E is being removed, and we | |
1072 | just remove it from the lists of exits. | |
1073 | If NEW_EDGE is true and E is not a loop exit, we | |
1074 | do not try to remove it from loop exit lists. */ | |
1075 | ||
1076 | void | |
1077 | rescan_loop_exit (edge e, bool new_edge, bool removed) | |
1078 | { | |
6270df4c | 1079 | struct loop_exit *exits = NULL, *exit; |
99b1c316 | 1080 | class loop *aloop, *cloop; |
6270df4c | 1081 | |
f87000d0 | 1082 | if (!loops_state_satisfies_p (LOOPS_HAVE_RECORDED_EXITS)) |
6270df4c ZD |
1083 | return; |
1084 | ||
1085 | if (!removed | |
1086 | && e->src->loop_father != NULL | |
1087 | && e->dest->loop_father != NULL | |
1088 | && !flow_bb_inside_loop_p (e->src->loop_father, e->dest)) | |
1089 | { | |
1090 | cloop = find_common_loop (e->src->loop_father, e->dest->loop_father); | |
1091 | for (aloop = e->src->loop_father; | |
1092 | aloop != cloop; | |
9ba025a2 | 1093 | aloop = loop_outer (aloop)) |
6270df4c | 1094 | { |
766090c2 | 1095 | exit = ggc_alloc<loop_exit> (); |
6270df4c ZD |
1096 | exit->e = e; |
1097 | ||
9e2f83a5 ZD |
1098 | exit->next = aloop->exits->next; |
1099 | exit->prev = aloop->exits; | |
6270df4c ZD |
1100 | exit->next->prev = exit; |
1101 | exit->prev->next = exit; | |
1102 | ||
1103 | exit->next_e = exits; | |
1104 | exits = exit; | |
1105 | } | |
b8698a0f | 1106 | } |
6270df4c ZD |
1107 | |
1108 | if (!exits && new_edge) | |
1109 | return; | |
1110 | ||
2a22f99c TS |
1111 | loop_exit **slot |
1112 | = current_loops->exits->find_slot_with_hash (e, htab_hash_pointer (e), | |
1113 | exits ? INSERT : NO_INSERT); | |
6270df4c ZD |
1114 | if (!slot) |
1115 | return; | |
1116 | ||
1117 | if (exits) | |
1118 | { | |
1119 | if (*slot) | |
2a22f99c | 1120 | loop_exit_hasher::remove (*slot); |
6270df4c ZD |
1121 | *slot = exits; |
1122 | } | |
1123 | else | |
2a22f99c | 1124 | current_loops->exits->clear_slot (slot); |
6270df4c ZD |
1125 | } |
1126 | ||
1127 | /* For each loop, record list of exit edges, and start maintaining these | |
1128 | lists. */ | |
1129 | ||
1130 | void | |
1131 | record_loop_exits (void) | |
1132 | { | |
1133 | basic_block bb; | |
1134 | edge_iterator ei; | |
1135 | edge e; | |
1136 | ||
4839cb59 ZD |
1137 | if (!current_loops) |
1138 | return; | |
1139 | ||
f87000d0 | 1140 | if (loops_state_satisfies_p (LOOPS_HAVE_RECORDED_EXITS)) |
6270df4c | 1141 | return; |
f87000d0 | 1142 | loops_state_set (LOOPS_HAVE_RECORDED_EXITS); |
6270df4c ZD |
1143 | |
1144 | gcc_assert (current_loops->exits == NULL); | |
2a22f99c TS |
1145 | current_loops->exits |
1146 | = hash_table<loop_exit_hasher>::create_ggc (2 * number_of_loops (cfun)); | |
6270df4c | 1147 | |
11cd3bed | 1148 | FOR_EACH_BB_FN (bb, cfun) |
6270df4c ZD |
1149 | { |
1150 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1151 | { | |
1152 | rescan_loop_exit (e, true, false); | |
1153 | } | |
1154 | } | |
1155 | } | |
1156 | ||
1157 | /* Dumps information about the exit in *SLOT to FILE. | |
1158 | Callback for htab_traverse. */ | |
1159 | ||
2a22f99c TS |
1160 | int |
1161 | dump_recorded_exit (loop_exit **slot, FILE *file) | |
6270df4c | 1162 | { |
2a22f99c | 1163 | struct loop_exit *exit = *slot; |
6270df4c ZD |
1164 | unsigned n = 0; |
1165 | edge e = exit->e; | |
1166 | ||
1167 | for (; exit != NULL; exit = exit->next_e) | |
1168 | n++; | |
1169 | ||
2a22f99c | 1170 | fprintf (file, "Edge %d->%d exits %u loops\n", |
6270df4c ZD |
1171 | e->src->index, e->dest->index, n); |
1172 | ||
1173 | return 1; | |
1174 | } | |
1175 | ||
1176 | /* Dumps the recorded exits of loops to FILE. */ | |
1177 | ||
1178 | extern void dump_recorded_exits (FILE *); | |
1179 | void | |
1180 | dump_recorded_exits (FILE *file) | |
1181 | { | |
1182 | if (!current_loops->exits) | |
1183 | return; | |
2a22f99c | 1184 | current_loops->exits->traverse<FILE *, dump_recorded_exit> (file); |
6270df4c ZD |
1185 | } |
1186 | ||
1187 | /* Releases lists of loop exits. */ | |
1188 | ||
1189 | void | |
61183076 | 1190 | release_recorded_exits (function *fn) |
6270df4c | 1191 | { |
61183076 RB |
1192 | gcc_assert (loops_state_satisfies_p (fn, LOOPS_HAVE_RECORDED_EXITS)); |
1193 | loops_for_fn (fn)->exits->empty (); | |
1194 | loops_for_fn (fn)->exits = NULL; | |
1195 | loops_state_clear (fn, LOOPS_HAVE_RECORDED_EXITS); | |
6270df4c ZD |
1196 | } |
1197 | ||
ca83d385 ZD |
1198 | /* Returns the list of the exit edges of a LOOP. */ |
1199 | ||
4b9d61f7 | 1200 | auto_vec<edge> |
f10d2d85 | 1201 | get_loop_exit_edges (const class loop *loop, basic_block *body) |
35b07080 | 1202 | { |
4b9d61f7 | 1203 | auto_vec<edge> edges; |
ca83d385 ZD |
1204 | edge e; |
1205 | unsigned i; | |
628f6a4e | 1206 | edge_iterator ei; |
6270df4c | 1207 | struct loop_exit *exit; |
35b07080 | 1208 | |
fefa31b5 | 1209 | gcc_assert (loop->latch != EXIT_BLOCK_PTR_FOR_FN (cfun)); |
35b07080 | 1210 | |
6270df4c ZD |
1211 | /* If we maintain the lists of exits, use them. Otherwise we must |
1212 | scan the body of the loop. */ | |
f87000d0 | 1213 | if (loops_state_satisfies_p (LOOPS_HAVE_RECORDED_EXITS)) |
6270df4c | 1214 | { |
9e2f83a5 | 1215 | for (exit = loop->exits->next; exit->e; exit = exit->next) |
9771b263 | 1216 | edges.safe_push (exit->e); |
6270df4c ZD |
1217 | } |
1218 | else | |
1219 | { | |
f10d2d85 RB |
1220 | bool body_from_caller = true; |
1221 | if (!body) | |
1222 | { | |
1223 | body = get_loop_body (loop); | |
1224 | body_from_caller = false; | |
1225 | } | |
6270df4c ZD |
1226 | for (i = 0; i < loop->num_nodes; i++) |
1227 | FOR_EACH_EDGE (e, ei, body[i]->succs) | |
1228 | { | |
1229 | if (!flow_bb_inside_loop_p (loop, e->dest)) | |
9771b263 | 1230 | edges.safe_push (e); |
6270df4c | 1231 | } |
f10d2d85 RB |
1232 | if (!body_from_caller) |
1233 | free (body); | |
6270df4c | 1234 | } |
35b07080 ZD |
1235 | |
1236 | return edges; | |
1237 | } | |
1238 | ||
50654f6c ZD |
1239 | /* Counts the number of conditional branches inside LOOP. */ |
1240 | ||
1241 | unsigned | |
99b1c316 | 1242 | num_loop_branches (const class loop *loop) |
50654f6c ZD |
1243 | { |
1244 | unsigned i, n; | |
1245 | basic_block * body; | |
1246 | ||
fefa31b5 | 1247 | gcc_assert (loop->latch != EXIT_BLOCK_PTR_FOR_FN (cfun)); |
50654f6c ZD |
1248 | |
1249 | body = get_loop_body (loop); | |
1250 | n = 0; | |
1251 | for (i = 0; i < loop->num_nodes; i++) | |
628f6a4e | 1252 | if (EDGE_COUNT (body[i]->succs) >= 2) |
50654f6c ZD |
1253 | n++; |
1254 | free (body); | |
1255 | ||
1256 | return n; | |
1257 | } | |
1258 | ||
2ecfd709 ZD |
1259 | /* Adds basic block BB to LOOP. */ |
1260 | void | |
99b1c316 | 1261 | add_bb_to_loop (basic_block bb, class loop *loop) |
d329e058 | 1262 | { |
9ba025a2 ZD |
1263 | unsigned i; |
1264 | loop_p ploop; | |
6270df4c ZD |
1265 | edge_iterator ei; |
1266 | edge e; | |
1267 | ||
1268 | gcc_assert (bb->loop_father == NULL); | |
1269 | bb->loop_father = loop; | |
6270df4c | 1270 | loop->num_nodes++; |
9771b263 | 1271 | FOR_EACH_VEC_SAFE_ELT (loop->superloops, i, ploop) |
9ba025a2 | 1272 | ploop->num_nodes++; |
6270df4c ZD |
1273 | |
1274 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1275 | { | |
1276 | rescan_loop_exit (e, true, false); | |
1277 | } | |
1278 | FOR_EACH_EDGE (e, ei, bb->preds) | |
1279 | { | |
1280 | rescan_loop_exit (e, true, false); | |
1281 | } | |
598ec7bd | 1282 | } |
2ecfd709 ZD |
1283 | |
1284 | /* Remove basic block BB from loops. */ | |
1285 | void | |
d329e058 AJ |
1286 | remove_bb_from_loops (basic_block bb) |
1287 | { | |
9771b263 | 1288 | unsigned i; |
99b1c316 | 1289 | class loop *loop = bb->loop_father; |
9ba025a2 | 1290 | loop_p ploop; |
6270df4c ZD |
1291 | edge_iterator ei; |
1292 | edge e; | |
1293 | ||
1294 | gcc_assert (loop != NULL); | |
1295 | loop->num_nodes--; | |
9771b263 | 1296 | FOR_EACH_VEC_SAFE_ELT (loop->superloops, i, ploop) |
9ba025a2 | 1297 | ploop->num_nodes--; |
6270df4c | 1298 | bb->loop_father = NULL; |
6270df4c ZD |
1299 | |
1300 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1301 | { | |
1302 | rescan_loop_exit (e, false, true); | |
1303 | } | |
1304 | FOR_EACH_EDGE (e, ei, bb->preds) | |
1305 | { | |
1306 | rescan_loop_exit (e, false, true); | |
1307 | } | |
a310245f | 1308 | } |
2ecfd709 ZD |
1309 | |
1310 | /* Finds nearest common ancestor in loop tree for given loops. */ | |
99b1c316 MS |
1311 | class loop * |
1312 | find_common_loop (class loop *loop_s, class loop *loop_d) | |
2ecfd709 | 1313 | { |
9ba025a2 ZD |
1314 | unsigned sdepth, ddepth; |
1315 | ||
2ecfd709 ZD |
1316 | if (!loop_s) return loop_d; |
1317 | if (!loop_d) return loop_s; | |
d329e058 | 1318 | |
9ba025a2 ZD |
1319 | sdepth = loop_depth (loop_s); |
1320 | ddepth = loop_depth (loop_d); | |
1321 | ||
1322 | if (sdepth < ddepth) | |
9771b263 | 1323 | loop_d = (*loop_d->superloops)[sdepth]; |
9ba025a2 | 1324 | else if (sdepth > ddepth) |
9771b263 | 1325 | loop_s = (*loop_s->superloops)[ddepth]; |
2ecfd709 ZD |
1326 | |
1327 | while (loop_s != loop_d) | |
1328 | { | |
9ba025a2 ZD |
1329 | loop_s = loop_outer (loop_s); |
1330 | loop_d = loop_outer (loop_d); | |
2ecfd709 ZD |
1331 | } |
1332 | return loop_s; | |
1333 | } | |
1334 | ||
42fd6772 ZD |
1335 | /* Removes LOOP from structures and frees its data. */ |
1336 | ||
1337 | void | |
99b1c316 | 1338 | delete_loop (class loop *loop) |
42fd6772 ZD |
1339 | { |
1340 | /* Remove the loop from structure. */ | |
1341 | flow_loop_tree_node_remove (loop); | |
1342 | ||
1343 | /* Remove loop from loops array. */ | |
9771b263 | 1344 | (*current_loops->larray)[loop->num] = NULL; |
42fd6772 ZD |
1345 | |
1346 | /* Free loop data. */ | |
1347 | flow_loop_free (loop); | |
1348 | } | |
1349 | ||
3d436d2a | 1350 | /* Cancels the LOOP; it must be innermost one. */ |
b00bf166 KH |
1351 | |
1352 | static void | |
99b1c316 | 1353 | cancel_loop (class loop *loop) |
3d436d2a ZD |
1354 | { |
1355 | basic_block *bbs; | |
1356 | unsigned i; | |
99b1c316 | 1357 | class loop *outer = loop_outer (loop); |
3d436d2a | 1358 | |
341c100f | 1359 | gcc_assert (!loop->inner); |
3d436d2a ZD |
1360 | |
1361 | /* Move blocks up one level (they should be removed as soon as possible). */ | |
1362 | bbs = get_loop_body (loop); | |
1363 | for (i = 0; i < loop->num_nodes; i++) | |
9ba025a2 | 1364 | bbs[i]->loop_father = outer; |
3d436d2a | 1365 | |
b78384e0 | 1366 | free (bbs); |
42fd6772 | 1367 | delete_loop (loop); |
3d436d2a ZD |
1368 | } |
1369 | ||
1370 | /* Cancels LOOP and all its subloops. */ | |
1371 | void | |
99b1c316 | 1372 | cancel_loop_tree (class loop *loop) |
3d436d2a ZD |
1373 | { |
1374 | while (loop->inner) | |
d73be268 ZD |
1375 | cancel_loop_tree (loop->inner); |
1376 | cancel_loop (loop); | |
3d436d2a ZD |
1377 | } |
1378 | ||
0ecf545c MS |
1379 | /* Disable warnings about missing quoting in GCC diagnostics for |
1380 | the verification errors. Their format strings don't follow GCC | |
1381 | diagnostic conventions and the calls are ultimately followed by | |
1382 | a deliberate ICE triggered by a failed assertion. */ | |
1383 | #if __GNUC__ >= 10 | |
1384 | # pragma GCC diagnostic push | |
1385 | # pragma GCC diagnostic ignored "-Wformat-diag" | |
1386 | #endif | |
1387 | ||
d73be268 | 1388 | /* Checks that information about loops is correct |
e0bb17a8 | 1389 | -- sizes of loops are all right |
2ecfd709 ZD |
1390 | -- results of get_loop_body really belong to the loop |
1391 | -- loop header have just single entry edge and single latch edge | |
1392 | -- loop latches have only single successor that is header of their loop | |
3d436d2a | 1393 | -- irreducible loops are correctly marked |
cc360b36 | 1394 | -- the cached loop depth and loop father of each bb is correct |
2ecfd709 | 1395 | */ |
24e47c76 | 1396 | DEBUG_FUNCTION void |
d73be268 | 1397 | verify_loop_structure (void) |
2ecfd709 | 1398 | { |
3d436d2a | 1399 | unsigned *sizes, i, j; |
a271b42d | 1400 | basic_block bb, *bbs; |
99b1c316 | 1401 | class loop *loop; |
2ecfd709 | 1402 | int err = 0; |
35b07080 | 1403 | edge e; |
0fc822d0 | 1404 | unsigned num = number_of_loops (cfun); |
6270df4c | 1405 | struct loop_exit *exit, *mexit; |
7d776ee2 | 1406 | bool dom_available = dom_info_available_p (CDI_DOMINATORS); |
2ecfd709 | 1407 | |
a9e0d843 RB |
1408 | if (loops_state_satisfies_p (LOOPS_NEED_FIXUP)) |
1409 | { | |
1410 | error ("loop verification on loop tree that needs fixup"); | |
1411 | err = 1; | |
1412 | } | |
1413 | ||
7d776ee2 RG |
1414 | /* We need up-to-date dominators, compute or verify them. */ |
1415 | if (!dom_available) | |
1416 | calculate_dominance_info (CDI_DOMINATORS); | |
1417 | else | |
1418 | verify_dominators (CDI_DOMINATORS); | |
510dbcce | 1419 | |
b0dd8c90 RB |
1420 | /* Check the loop tree root. */ |
1421 | if (current_loops->tree_root->header != ENTRY_BLOCK_PTR_FOR_FN (cfun) | |
1422 | || current_loops->tree_root->latch != EXIT_BLOCK_PTR_FOR_FN (cfun) | |
1423 | || (current_loops->tree_root->num_nodes | |
1424 | != (unsigned) n_basic_blocks_for_fn (cfun))) | |
1425 | { | |
1426 | error ("corrupt loop tree root"); | |
1427 | err = 1; | |
1428 | } | |
1429 | ||
f64fb0fa | 1430 | /* Check the headers. */ |
11cd3bed | 1431 | FOR_EACH_BB_FN (bb, cfun) |
a271b42d | 1432 | if (bb_loop_header_p (bb)) |
f64fb0fa | 1433 | { |
a271b42d RB |
1434 | if (bb->loop_father->header == NULL) |
1435 | { | |
1436 | error ("loop with header %d marked for removal", bb->index); | |
1437 | err = 1; | |
1438 | } | |
1439 | else if (bb->loop_father->header != bb) | |
1440 | { | |
1441 | error ("loop with header %d not in loop tree", bb->index); | |
1442 | err = 1; | |
1443 | } | |
1444 | } | |
1445 | else if (bb->loop_father->header == bb) | |
1446 | { | |
1447 | error ("non-loop with header %d not marked for removal", bb->index); | |
f64fb0fa MP |
1448 | err = 1; |
1449 | } | |
1450 | ||
a271b42d | 1451 | /* Check the recorded loop father and sizes of loops. */ |
7ba9e72d | 1452 | auto_sbitmap visited (last_basic_block_for_fn (cfun)); |
f61e445a | 1453 | bitmap_clear (visited); |
0cae8d31 | 1454 | bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun)); |
e41ba804 | 1455 | for (auto loop : loops_list (cfun, LI_FROM_INNERMOST)) |
cc360b36 | 1456 | { |
a271b42d | 1457 | unsigned n; |
cc360b36 | 1458 | |
a271b42d RB |
1459 | if (loop->header == NULL) |
1460 | { | |
1461 | error ("removed loop %d in loop tree", loop->num); | |
1462 | err = 1; | |
1463 | continue; | |
1464 | } | |
1465 | ||
0cae8d31 | 1466 | n = get_loop_body_with_size (loop, bbs, n_basic_blocks_for_fn (cfun)); |
a271b42d RB |
1467 | if (loop->num_nodes != n) |
1468 | { | |
1469 | error ("size of loop %d should be %d, not %d", | |
1470 | loop->num, n, loop->num_nodes); | |
1471 | err = 1; | |
1472 | } | |
1473 | ||
1474 | for (j = 0; j < n; j++) | |
cc360b36 SB |
1475 | { |
1476 | bb = bbs[j]; | |
1477 | ||
0375167b RB |
1478 | if (!flow_bb_inside_loop_p (loop, bb)) |
1479 | { | |
1480 | error ("bb %d does not belong to loop %d", | |
1481 | bb->index, loop->num); | |
1482 | err = 1; | |
1483 | } | |
1484 | ||
cc360b36 | 1485 | /* Ignore this block if it is in an inner loop. */ |
d7c028c0 | 1486 | if (bitmap_bit_p (visited, bb->index)) |
cc360b36 | 1487 | continue; |
d7c028c0 | 1488 | bitmap_set_bit (visited, bb->index); |
cc360b36 SB |
1489 | |
1490 | if (bb->loop_father != loop) | |
1491 | { | |
1492 | error ("bb %d has father loop %d, should be loop %d", | |
1493 | bb->index, bb->loop_father->num, loop->num); | |
1494 | err = 1; | |
1495 | } | |
1496 | } | |
cc360b36 | 1497 | } |
a271b42d | 1498 | free (bbs); |
2ecfd709 ZD |
1499 | |
1500 | /* Check headers and latches. */ | |
e41ba804 | 1501 | for (auto loop : loops_list (cfun, 0)) |
2ecfd709 | 1502 | { |
42fd6772 | 1503 | i = loop->num; |
a271b42d RB |
1504 | if (loop->header == NULL) |
1505 | continue; | |
0375167b RB |
1506 | if (!bb_loop_header_p (loop->header)) |
1507 | { | |
1508 | error ("loop %d%'s header is not a loop header", i); | |
1509 | err = 1; | |
1510 | } | |
f87000d0 | 1511 | if (loops_state_satisfies_p (LOOPS_HAVE_PREHEADERS) |
628f6a4e | 1512 | && EDGE_COUNT (loop->header->preds) != 2) |
2ecfd709 | 1513 | { |
d8a07487 | 1514 | error ("loop %d%'s header does not have exactly 2 entries", i); |
2ecfd709 ZD |
1515 | err = 1; |
1516 | } | |
6aaf596b RB |
1517 | if (loop->latch) |
1518 | { | |
1519 | if (!find_edge (loop->latch, loop->header)) | |
1520 | { | |
1521 | error ("loop %d%'s latch does not have an edge to its header", i); | |
1522 | err = 1; | |
1523 | } | |
1524 | if (!dominated_by_p (CDI_DOMINATORS, loop->latch, loop->header)) | |
1525 | { | |
1526 | error ("loop %d%'s latch is not dominated by its header", i); | |
1527 | err = 1; | |
1528 | } | |
1529 | } | |
f87000d0 | 1530 | if (loops_state_satisfies_p (LOOPS_HAVE_SIMPLE_LATCHES)) |
2ecfd709 | 1531 | { |
c5cbcccf | 1532 | if (!single_succ_p (loop->latch)) |
2ecfd709 | 1533 | { |
d8a07487 | 1534 | error ("loop %d%'s latch does not have exactly 1 successor", i); |
2ecfd709 ZD |
1535 | err = 1; |
1536 | } | |
c5cbcccf | 1537 | if (single_succ (loop->latch) != loop->header) |
2ecfd709 | 1538 | { |
d8a07487 | 1539 | error ("loop %d%'s latch does not have header as successor", i); |
2ecfd709 ZD |
1540 | err = 1; |
1541 | } | |
1542 | if (loop->latch->loop_father != loop) | |
1543 | { | |
d8a07487 | 1544 | error ("loop %d%'s latch does not belong directly to it", i); |
2ecfd709 ZD |
1545 | err = 1; |
1546 | } | |
1547 | } | |
1548 | if (loop->header->loop_father != loop) | |
1549 | { | |
d8a07487 | 1550 | error ("loop %d%'s header does not belong directly to it", i); |
2ecfd709 ZD |
1551 | err = 1; |
1552 | } | |
dfef1164 | 1553 | if (loops_state_satisfies_p (LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS)) |
35b07080 | 1554 | { |
dfef1164 RB |
1555 | edge_iterator ei; |
1556 | FOR_EACH_EDGE (e, ei, loop->header->preds) | |
1557 | if (dominated_by_p (CDI_DOMINATORS, e->src, loop->header) | |
1558 | && e->flags & EDGE_IRREDUCIBLE_LOOP) | |
1559 | { | |
1560 | error ("loop %d%'s latch is marked as part of irreducible" | |
1561 | " region", i); | |
1562 | err = 1; | |
1563 | } | |
35b07080 | 1564 | } |
2ecfd709 ZD |
1565 | } |
1566 | ||
3d436d2a | 1567 | /* Check irreducible loops. */ |
f87000d0 | 1568 | if (loops_state_satisfies_p (LOOPS_HAVE_MARKED_IRREDUCIBLE_REGIONS)) |
3d436d2a | 1569 | { |
e144a2b3 | 1570 | auto_edge_flag saved_irr_mask (cfun); |
3d436d2a | 1571 | /* Record old info. */ |
7ba9e72d | 1572 | auto_sbitmap irreds (last_basic_block_for_fn (cfun)); |
11cd3bed | 1573 | FOR_EACH_BB_FN (bb, cfun) |
35b07080 | 1574 | { |
628f6a4e | 1575 | edge_iterator ei; |
35b07080 | 1576 | if (bb->flags & BB_IRREDUCIBLE_LOOP) |
d7c028c0 | 1577 | bitmap_set_bit (irreds, bb->index); |
35b07080 | 1578 | else |
d7c028c0 | 1579 | bitmap_clear_bit (irreds, bb->index); |
628f6a4e | 1580 | FOR_EACH_EDGE (e, ei, bb->succs) |
35b07080 | 1581 | if (e->flags & EDGE_IRREDUCIBLE_LOOP) |
e144a2b3 | 1582 | e->flags |= saved_irr_mask; |
35b07080 | 1583 | } |
3d436d2a ZD |
1584 | |
1585 | /* Recount it. */ | |
d73be268 | 1586 | mark_irreducible_loops (); |
3d436d2a ZD |
1587 | |
1588 | /* Compare. */ | |
11cd3bed | 1589 | FOR_EACH_BB_FN (bb, cfun) |
3d436d2a | 1590 | { |
628f6a4e BE |
1591 | edge_iterator ei; |
1592 | ||
3d436d2a | 1593 | if ((bb->flags & BB_IRREDUCIBLE_LOOP) |
d7c028c0 | 1594 | && !bitmap_bit_p (irreds, bb->index)) |
3d436d2a | 1595 | { |
ab532386 | 1596 | error ("basic block %d should be marked irreducible", bb->index); |
3d436d2a ZD |
1597 | err = 1; |
1598 | } | |
1599 | else if (!(bb->flags & BB_IRREDUCIBLE_LOOP) | |
d7c028c0 | 1600 | && bitmap_bit_p (irreds, bb->index)) |
3d436d2a | 1601 | { |
ab532386 | 1602 | error ("basic block %d should not be marked irreducible", bb->index); |
3d436d2a ZD |
1603 | err = 1; |
1604 | } | |
628f6a4e | 1605 | FOR_EACH_EDGE (e, ei, bb->succs) |
35b07080 ZD |
1606 | { |
1607 | if ((e->flags & EDGE_IRREDUCIBLE_LOOP) | |
e144a2b3 | 1608 | && !(e->flags & saved_irr_mask)) |
35b07080 | 1609 | { |
ab532386 | 1610 | error ("edge from %d to %d should be marked irreducible", |
35b07080 ZD |
1611 | e->src->index, e->dest->index); |
1612 | err = 1; | |
1613 | } | |
1614 | else if (!(e->flags & EDGE_IRREDUCIBLE_LOOP) | |
e144a2b3 | 1615 | && (e->flags & saved_irr_mask)) |
35b07080 | 1616 | { |
ab532386 | 1617 | error ("edge from %d to %d should not be marked irreducible", |
35b07080 ZD |
1618 | e->src->index, e->dest->index); |
1619 | err = 1; | |
1620 | } | |
e144a2b3 | 1621 | e->flags &= ~saved_irr_mask; |
35b07080 | 1622 | } |
3d436d2a | 1623 | } |
3d436d2a ZD |
1624 | } |
1625 | ||
6270df4c | 1626 | /* Check the recorded loop exits. */ |
e41ba804 | 1627 | for (auto loop : loops_list (cfun, 0)) |
82b85a85 | 1628 | { |
9e2f83a5 | 1629 | if (!loop->exits || loop->exits->e != NULL) |
6270df4c ZD |
1630 | { |
1631 | error ("corrupted head of the exits list of loop %d", | |
1632 | loop->num); | |
1633 | err = 1; | |
1634 | } | |
1635 | else | |
1636 | { | |
1637 | /* Check that the list forms a cycle, and all elements except | |
1638 | for the head are nonnull. */ | |
9e2f83a5 | 1639 | for (mexit = loop->exits, exit = mexit->next, i = 0; |
6270df4c ZD |
1640 | exit->e && exit != mexit; |
1641 | exit = exit->next) | |
1642 | { | |
1643 | if (i++ & 1) | |
1644 | mexit = mexit->next; | |
1645 | } | |
1646 | ||
9e2f83a5 | 1647 | if (exit != loop->exits) |
6270df4c ZD |
1648 | { |
1649 | error ("corrupted exits list of loop %d", loop->num); | |
1650 | err = 1; | |
1651 | } | |
1652 | } | |
1653 | ||
f87000d0 | 1654 | if (!loops_state_satisfies_p (LOOPS_HAVE_RECORDED_EXITS)) |
6270df4c | 1655 | { |
9e2f83a5 | 1656 | if (loop->exits->next != loop->exits) |
6270df4c ZD |
1657 | { |
1658 | error ("nonempty exits list of loop %d, but exits are not recorded", | |
1659 | loop->num); | |
1660 | err = 1; | |
1661 | } | |
1662 | } | |
1663 | } | |
1664 | ||
f87000d0 | 1665 | if (loops_state_satisfies_p (LOOPS_HAVE_RECORDED_EXITS)) |
6270df4c ZD |
1666 | { |
1667 | unsigned n_exits = 0, eloops; | |
1668 | ||
a271b42d | 1669 | sizes = XCNEWVEC (unsigned, num); |
42fd6772 | 1670 | memset (sizes, 0, sizeof (unsigned) * num); |
11cd3bed | 1671 | FOR_EACH_BB_FN (bb, cfun) |
82b85a85 | 1672 | { |
628f6a4e | 1673 | edge_iterator ei; |
d73be268 | 1674 | if (bb->loop_father == current_loops->tree_root) |
82b85a85 | 1675 | continue; |
628f6a4e | 1676 | FOR_EACH_EDGE (e, ei, bb->succs) |
82b85a85 | 1677 | { |
82b85a85 ZD |
1678 | if (flow_bb_inside_loop_p (bb->loop_father, e->dest)) |
1679 | continue; | |
1680 | ||
6270df4c ZD |
1681 | n_exits++; |
1682 | exit = get_exit_descriptions (e); | |
1683 | if (!exit) | |
1684 | { | |
d8a07487 | 1685 | error ("exit %d->%d not recorded", |
6270df4c ZD |
1686 | e->src->index, e->dest->index); |
1687 | err = 1; | |
1688 | } | |
1689 | eloops = 0; | |
1690 | for (; exit; exit = exit->next_e) | |
1691 | eloops++; | |
1692 | ||
82b85a85 | 1693 | for (loop = bb->loop_father; |
661bc682 RB |
1694 | loop != e->dest->loop_father |
1695 | /* When a loop exit is also an entry edge which | |
1696 | can happen when avoiding CFG manipulations | |
1697 | then the last loop exited is the outer loop | |
1698 | of the loop entered. */ | |
1699 | && loop != loop_outer (e->dest->loop_father); | |
9ba025a2 | 1700 | loop = loop_outer (loop)) |
82b85a85 | 1701 | { |
6270df4c | 1702 | eloops--; |
82b85a85 | 1703 | sizes[loop->num]++; |
6270df4c ZD |
1704 | } |
1705 | ||
1706 | if (eloops != 0) | |
1707 | { | |
0ecf545c | 1708 | error ("wrong list of exited loops for edge %d->%d", |
6270df4c ZD |
1709 | e->src->index, e->dest->index); |
1710 | err = 1; | |
82b85a85 ZD |
1711 | } |
1712 | } | |
1713 | } | |
1714 | ||
2a22f99c | 1715 | if (n_exits != current_loops->exits->elements ()) |
82b85a85 | 1716 | { |
d8a07487 | 1717 | error ("too many loop exits recorded"); |
6270df4c ZD |
1718 | err = 1; |
1719 | } | |
82b85a85 | 1720 | |
e41ba804 | 1721 | for (auto loop : loops_list (cfun, 0)) |
6270df4c ZD |
1722 | { |
1723 | eloops = 0; | |
9e2f83a5 | 1724 | for (exit = loop->exits->next; exit->e; exit = exit->next) |
6270df4c ZD |
1725 | eloops++; |
1726 | if (eloops != sizes[loop->num]) | |
82b85a85 | 1727 | { |
6270df4c ZD |
1728 | error ("%d exits recorded for loop %d (having %d exits)", |
1729 | eloops, loop->num, sizes[loop->num]); | |
82b85a85 ZD |
1730 | err = 1; |
1731 | } | |
1732 | } | |
a271b42d RB |
1733 | |
1734 | free (sizes); | |
82b85a85 ZD |
1735 | } |
1736 | ||
341c100f | 1737 | gcc_assert (!err); |
82b85a85 | 1738 | |
7d776ee2 RG |
1739 | if (!dom_available) |
1740 | free_dominance_info (CDI_DOMINATORS); | |
2ecfd709 ZD |
1741 | } |
1742 | ||
0ecf545c MS |
1743 | #if __GNUC__ >= 10 |
1744 | # pragma GCC diagnostic pop | |
1745 | #endif | |
1746 | ||
2ecfd709 ZD |
1747 | /* Returns latch edge of LOOP. */ |
1748 | edge | |
99b1c316 | 1749 | loop_latch_edge (const class loop *loop) |
2ecfd709 | 1750 | { |
9ff3d2de | 1751 | return find_edge (loop->latch, loop->header); |
402209ff | 1752 | } |
2ecfd709 ZD |
1753 | |
1754 | /* Returns preheader edge of LOOP. */ | |
1755 | edge | |
99b1c316 | 1756 | loop_preheader_edge (const class loop *loop) |
2ecfd709 ZD |
1757 | { |
1758 | edge e; | |
628f6a4e | 1759 | edge_iterator ei; |
2ecfd709 | 1760 | |
a68f286c RB |
1761 | gcc_assert (loops_state_satisfies_p (LOOPS_HAVE_PREHEADERS) |
1762 | && ! loops_state_satisfies_p (LOOPS_MAY_HAVE_MULTIPLE_LATCHES)); | |
c7b852c8 | 1763 | |
628f6a4e BE |
1764 | FOR_EACH_EDGE (e, ei, loop->header->preds) |
1765 | if (e->src != loop->latch) | |
1766 | break; | |
2ecfd709 | 1767 | |
a68f286c RB |
1768 | if (! e) |
1769 | { | |
1770 | gcc_assert (! loop_outer (loop)); | |
1771 | return single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun)); | |
1772 | } | |
1773 | ||
2ecfd709 ZD |
1774 | return e; |
1775 | } | |
70388d94 ZD |
1776 | |
1777 | /* Returns true if E is an exit of LOOP. */ | |
1778 | ||
1779 | bool | |
99b1c316 | 1780 | loop_exit_edge_p (const class loop *loop, const_edge e) |
70388d94 ZD |
1781 | { |
1782 | return (flow_bb_inside_loop_p (loop, e->src) | |
1783 | && !flow_bb_inside_loop_p (loop, e->dest)); | |
1784 | } | |
ac8f6c69 ZD |
1785 | |
1786 | /* Returns the single exit edge of LOOP, or NULL if LOOP has either no exit | |
6270df4c ZD |
1787 | or more than one exit. If loops do not have the exits recorded, NULL |
1788 | is returned always. */ | |
ac8f6c69 ZD |
1789 | |
1790 | edge | |
99b1c316 | 1791 | single_exit (const class loop *loop) |
ac8f6c69 | 1792 | { |
9e2f83a5 | 1793 | struct loop_exit *exit = loop->exits->next; |
ac8f6c69 | 1794 | |
f87000d0 | 1795 | if (!loops_state_satisfies_p (LOOPS_HAVE_RECORDED_EXITS)) |
6270df4c | 1796 | return NULL; |
ac8f6c69 | 1797 | |
9e2f83a5 | 1798 | if (exit->e && exit->next == loop->exits) |
6270df4c ZD |
1799 | return exit->e; |
1800 | else | |
1801 | return NULL; | |
ac8f6c69 | 1802 | } |
f8bf9252 | 1803 | |
f4ce375d | 1804 | /* Returns true when BB has an incoming edge exiting LOOP. */ |
f8bf9252 SP |
1805 | |
1806 | bool | |
99b1c316 | 1807 | loop_exits_to_bb_p (class loop *loop, basic_block bb) |
f8bf9252 SP |
1808 | { |
1809 | edge e; | |
1810 | edge_iterator ei; | |
1811 | ||
1812 | FOR_EACH_EDGE (e, ei, bb->preds) | |
1813 | if (loop_exit_edge_p (loop, e)) | |
1814 | return true; | |
1815 | ||
1816 | return false; | |
1817 | } | |
f4ce375d VK |
1818 | |
1819 | /* Returns true when BB has an outgoing edge exiting LOOP. */ | |
1820 | ||
1821 | bool | |
99b1c316 | 1822 | loop_exits_from_bb_p (class loop *loop, basic_block bb) |
f4ce375d VK |
1823 | { |
1824 | edge e; | |
1825 | edge_iterator ei; | |
1826 | ||
1827 | FOR_EACH_EDGE (e, ei, bb->succs) | |
1828 | if (loop_exit_edge_p (loop, e)) | |
1829 | return true; | |
1830 | ||
1831 | return false; | |
1832 | } | |
e25a6711 TJ |
1833 | |
1834 | /* Return location corresponding to the loop control condition if possible. */ | |
1835 | ||
4f5b9c80 | 1836 | dump_user_location_t |
99b1c316 | 1837 | get_loop_location (class loop *loop) |
e25a6711 | 1838 | { |
9d56eaa2 | 1839 | rtx_insn *insn = NULL; |
99b1c316 | 1840 | class niter_desc *desc = NULL; |
e25a6711 TJ |
1841 | edge exit; |
1842 | ||
1843 | /* For a for or while loop, we would like to return the location | |
1844 | of the for or while statement, if possible. To do this, look | |
1845 | for the branch guarding the loop back-edge. */ | |
1846 | ||
1847 | /* If this is a simple loop with an in_edge, then the loop control | |
1848 | branch is typically at the end of its source. */ | |
1849 | desc = get_simple_loop_desc (loop); | |
1850 | if (desc->in_edge) | |
1851 | { | |
1852 | FOR_BB_INSNS_REVERSE (desc->in_edge->src, insn) | |
1853 | { | |
1854 | if (INSN_P (insn) && INSN_HAS_LOCATION (insn)) | |
4f5b9c80 | 1855 | return insn; |
e25a6711 TJ |
1856 | } |
1857 | } | |
1858 | /* If loop has a single exit, then the loop control branch | |
1859 | must be at the end of its source. */ | |
1860 | if ((exit = single_exit (loop))) | |
1861 | { | |
1862 | FOR_BB_INSNS_REVERSE (exit->src, insn) | |
1863 | { | |
1864 | if (INSN_P (insn) && INSN_HAS_LOCATION (insn)) | |
4f5b9c80 | 1865 | return insn; |
e25a6711 TJ |
1866 | } |
1867 | } | |
1868 | /* Next check the latch, to see if it is non-empty. */ | |
1869 | FOR_BB_INSNS_REVERSE (loop->latch, insn) | |
1870 | { | |
1871 | if (INSN_P (insn) && INSN_HAS_LOCATION (insn)) | |
4f5b9c80 | 1872 | return insn; |
e25a6711 TJ |
1873 | } |
1874 | /* Finally, if none of the above identifies the loop control branch, | |
1875 | return the first location in the loop header. */ | |
1876 | FOR_BB_INSNS (loop->header, insn) | |
1877 | { | |
1878 | if (INSN_P (insn) && INSN_HAS_LOCATION (insn)) | |
4f5b9c80 | 1879 | return insn; |
e25a6711 TJ |
1880 | } |
1881 | /* If all else fails, simply return the current function location. */ | |
4f5b9c80 | 1882 | return dump_user_location_t::from_function_decl (current_function_decl); |
e25a6711 TJ |
1883 | } |
1884 | ||
71343877 AM |
1885 | /* Records that every statement in LOOP is executed I_BOUND times. |
1886 | REALISTIC is true if I_BOUND is expected to be close to the real number | |
1887 | of iterations. UPPER is true if we are sure the loop iterates at most | |
1888 | I_BOUND times. */ | |
1889 | ||
1890 | void | |
99b1c316 | 1891 | record_niter_bound (class loop *loop, const widest_int &i_bound, |
807e902e | 1892 | bool realistic, bool upper) |
71343877 AM |
1893 | { |
1894 | /* Update the bounds only when there is no previous estimation, or when the | |
1895 | current estimation is smaller. */ | |
1896 | if (upper | |
1897 | && (!loop->any_upper_bound | |
807e902e | 1898 | || wi::ltu_p (i_bound, loop->nb_iterations_upper_bound))) |
71343877 AM |
1899 | { |
1900 | loop->any_upper_bound = true; | |
1901 | loop->nb_iterations_upper_bound = i_bound; | |
105e29c5 JH |
1902 | if (!loop->any_likely_upper_bound) |
1903 | { | |
1904 | loop->any_likely_upper_bound = true; | |
1905 | loop->nb_iterations_likely_upper_bound = i_bound; | |
1906 | } | |
71343877 AM |
1907 | } |
1908 | if (realistic | |
1909 | && (!loop->any_estimate | |
807e902e | 1910 | || wi::ltu_p (i_bound, loop->nb_iterations_estimate))) |
71343877 AM |
1911 | { |
1912 | loop->any_estimate = true; | |
1913 | loop->nb_iterations_estimate = i_bound; | |
1914 | } | |
105e29c5 JH |
1915 | if (!realistic |
1916 | && (!loop->any_likely_upper_bound | |
1917 | || wi::ltu_p (i_bound, loop->nb_iterations_likely_upper_bound))) | |
1918 | { | |
1919 | loop->any_likely_upper_bound = true; | |
1920 | loop->nb_iterations_likely_upper_bound = i_bound; | |
1921 | } | |
71343877 AM |
1922 | |
1923 | /* If an upper bound is smaller than the realistic estimate of the | |
1924 | number of iterations, use the upper bound instead. */ | |
1925 | if (loop->any_upper_bound | |
1926 | && loop->any_estimate | |
807e902e KZ |
1927 | && wi::ltu_p (loop->nb_iterations_upper_bound, |
1928 | loop->nb_iterations_estimate)) | |
71343877 | 1929 | loop->nb_iterations_estimate = loop->nb_iterations_upper_bound; |
105e29c5 JH |
1930 | if (loop->any_upper_bound |
1931 | && loop->any_likely_upper_bound | |
1932 | && wi::ltu_p (loop->nb_iterations_upper_bound, | |
1933 | loop->nb_iterations_likely_upper_bound)) | |
1934 | loop->nb_iterations_likely_upper_bound = loop->nb_iterations_upper_bound; | |
71343877 AM |
1935 | } |
1936 | ||
1ef88893 | 1937 | /* Similar to get_estimated_loop_iterations, but returns the estimate only |
71343877 AM |
1938 | if it fits to HOST_WIDE_INT. If this is not the case, or the estimate |
1939 | on the number of iterations of LOOP could not be derived, returns -1. */ | |
1940 | ||
1941 | HOST_WIDE_INT | |
99b1c316 | 1942 | get_estimated_loop_iterations_int (class loop *loop) |
71343877 | 1943 | { |
807e902e | 1944 | widest_int nit; |
71343877 AM |
1945 | HOST_WIDE_INT hwi_nit; |
1946 | ||
1947 | if (!get_estimated_loop_iterations (loop, &nit)) | |
1948 | return -1; | |
1949 | ||
807e902e | 1950 | if (!wi::fits_shwi_p (nit)) |
71343877 AM |
1951 | return -1; |
1952 | hwi_nit = nit.to_shwi (); | |
1953 | ||
1954 | return hwi_nit < 0 ? -1 : hwi_nit; | |
1955 | } | |
1956 | ||
1957 | /* Returns an upper bound on the number of executions of statements | |
1958 | in the LOOP. For statements before the loop exit, this exceeds | |
1959 | the number of execution of the latch by one. */ | |
1960 | ||
1961 | HOST_WIDE_INT | |
99b1c316 | 1962 | max_stmt_executions_int (class loop *loop) |
71343877 | 1963 | { |
1ef88893 | 1964 | HOST_WIDE_INT nit = get_max_loop_iterations_int (loop); |
71343877 AM |
1965 | HOST_WIDE_INT snit; |
1966 | ||
1967 | if (nit == -1) | |
1968 | return -1; | |
1969 | ||
1970 | snit = (HOST_WIDE_INT) ((unsigned HOST_WIDE_INT) nit + 1); | |
1971 | ||
1972 | /* If the computation overflows, return -1. */ | |
1973 | return snit < 0 ? -1 : snit; | |
1974 | } | |
1975 | ||
105e29c5 JH |
1976 | /* Returns an likely upper bound on the number of executions of statements |
1977 | in the LOOP. For statements before the loop exit, this exceeds | |
1978 | the number of execution of the latch by one. */ | |
1979 | ||
1980 | HOST_WIDE_INT | |
99b1c316 | 1981 | likely_max_stmt_executions_int (class loop *loop) |
105e29c5 JH |
1982 | { |
1983 | HOST_WIDE_INT nit = get_likely_max_loop_iterations_int (loop); | |
1984 | HOST_WIDE_INT snit; | |
1985 | ||
1986 | if (nit == -1) | |
1987 | return -1; | |
1988 | ||
1989 | snit = (HOST_WIDE_INT) ((unsigned HOST_WIDE_INT) nit + 1); | |
1990 | ||
1991 | /* If the computation overflows, return -1. */ | |
1992 | return snit < 0 ? -1 : snit; | |
1993 | } | |
1994 | ||
71343877 AM |
1995 | /* Sets NIT to the estimated number of executions of the latch of the |
1996 | LOOP. If we have no reliable estimate, the function returns false, otherwise | |
1997 | returns true. */ | |
1998 | ||
1999 | bool | |
99b1c316 | 2000 | get_estimated_loop_iterations (class loop *loop, widest_int *nit) |
71343877 AM |
2001 | { |
2002 | /* Even if the bound is not recorded, possibly we can derrive one from | |
2003 | profile. */ | |
2004 | if (!loop->any_estimate) | |
2005 | { | |
3995f3a2 | 2006 | if (loop->header->count.reliable_p ()) |
71343877 | 2007 | { |
807e902e | 2008 | *nit = gcov_type_to_wide_int |
71343877 AM |
2009 | (expected_loop_iterations_unbounded (loop) + 1); |
2010 | return true; | |
2011 | } | |
2012 | return false; | |
2013 | } | |
2014 | ||
2015 | *nit = loop->nb_iterations_estimate; | |
2016 | return true; | |
2017 | } | |
2018 | ||
2019 | /* Sets NIT to an upper bound for the maximum number of executions of the | |
2020 | latch of the LOOP. If we have no reliable estimate, the function returns | |
2021 | false, otherwise returns true. */ | |
2022 | ||
2023 | bool | |
99b1c316 | 2024 | get_max_loop_iterations (const class loop *loop, widest_int *nit) |
71343877 AM |
2025 | { |
2026 | if (!loop->any_upper_bound) | |
2027 | return false; | |
2028 | ||
2029 | *nit = loop->nb_iterations_upper_bound; | |
2030 | return true; | |
2031 | } | |
1ef88893 AM |
2032 | |
2033 | /* Similar to get_max_loop_iterations, but returns the estimate only | |
2034 | if it fits to HOST_WIDE_INT. If this is not the case, or the estimate | |
2035 | on the number of iterations of LOOP could not be derived, returns -1. */ | |
2036 | ||
2037 | HOST_WIDE_INT | |
99b1c316 | 2038 | get_max_loop_iterations_int (const class loop *loop) |
1ef88893 | 2039 | { |
807e902e | 2040 | widest_int nit; |
1ef88893 AM |
2041 | HOST_WIDE_INT hwi_nit; |
2042 | ||
2043 | if (!get_max_loop_iterations (loop, &nit)) | |
2044 | return -1; | |
2045 | ||
807e902e | 2046 | if (!wi::fits_shwi_p (nit)) |
1ef88893 AM |
2047 | return -1; |
2048 | hwi_nit = nit.to_shwi (); | |
2049 | ||
2050 | return hwi_nit < 0 ? -1 : hwi_nit; | |
2051 | } | |
2052 | ||
105e29c5 JH |
2053 | /* Sets NIT to an upper bound for the maximum number of executions of the |
2054 | latch of the LOOP. If we have no reliable estimate, the function returns | |
2055 | false, otherwise returns true. */ | |
2056 | ||
2057 | bool | |
99b1c316 | 2058 | get_likely_max_loop_iterations (class loop *loop, widest_int *nit) |
105e29c5 JH |
2059 | { |
2060 | if (!loop->any_likely_upper_bound) | |
2061 | return false; | |
2062 | ||
2063 | *nit = loop->nb_iterations_likely_upper_bound; | |
2064 | return true; | |
2065 | } | |
2066 | ||
2067 | /* Similar to get_max_loop_iterations, but returns the estimate only | |
2068 | if it fits to HOST_WIDE_INT. If this is not the case, or the estimate | |
2069 | on the number of iterations of LOOP could not be derived, returns -1. */ | |
2070 | ||
2071 | HOST_WIDE_INT | |
99b1c316 | 2072 | get_likely_max_loop_iterations_int (class loop *loop) |
105e29c5 JH |
2073 | { |
2074 | widest_int nit; | |
2075 | HOST_WIDE_INT hwi_nit; | |
2076 | ||
2077 | if (!get_likely_max_loop_iterations (loop, &nit)) | |
2078 | return -1; | |
2079 | ||
2080 | if (!wi::fits_shwi_p (nit)) | |
2081 | return -1; | |
2082 | hwi_nit = nit.to_shwi (); | |
2083 | ||
2084 | return hwi_nit < 0 ? -1 : hwi_nit; | |
2085 | } | |
2086 | ||
4484a35a | 2087 | /* Returns the loop depth of the loop BB belongs to. */ |
1ef88893 | 2088 | |
4484a35a AM |
2089 | int |
2090 | bb_loop_depth (const_basic_block bb) | |
2091 | { | |
2092 | return bb->loop_father ? loop_depth (bb->loop_father) : 0; | |
2093 | } | |
08c13199 RB |
2094 | |
2095 | /* Marks LOOP for removal and sets LOOPS_NEED_FIXUP. */ | |
2096 | ||
2097 | void | |
2098 | mark_loop_for_removal (loop_p loop) | |
2099 | { | |
024660c5 RB |
2100 | if (loop->header == NULL) |
2101 | return; | |
e4ca2139 | 2102 | loop->former_header = loop->header; |
08c13199 RB |
2103 | loop->header = NULL; |
2104 | loop->latch = NULL; | |
2105 | loops_state_set (LOOPS_NEED_FIXUP); | |
2106 | } | |
d0a5624b KL |
2107 | |
2108 | /* Starting from loop tree ROOT, walk loop tree as the visiting | |
2109 | order specified by FLAGS. The supported visiting orders | |
2110 | are: | |
2111 | - LI_ONLY_INNERMOST | |
2112 | - LI_FROM_INNERMOST | |
2113 | - Preorder (if neither of above is specified) */ | |
2114 | ||
2115 | void | |
2116 | loops_list::walk_loop_tree (class loop *root, unsigned flags) | |
2117 | { | |
2118 | bool only_innermost_p = flags & LI_ONLY_INNERMOST; | |
2119 | bool from_innermost_p = flags & LI_FROM_INNERMOST; | |
2120 | bool preorder_p = !(only_innermost_p || from_innermost_p); | |
2121 | ||
2122 | /* Early handle root without any inner loops, make later | |
2123 | processing simpler, that is all loops processed in the | |
2124 | following while loop are impossible to be root. */ | |
2125 | if (!root->inner) | |
2126 | { | |
2127 | if (flags & LI_INCLUDE_ROOT) | |
2128 | this->to_visit.quick_push (root->num); | |
2129 | return; | |
2130 | } | |
2131 | else if (preorder_p && flags & LI_INCLUDE_ROOT) | |
2132 | this->to_visit.quick_push (root->num); | |
2133 | ||
2134 | class loop *aloop; | |
2135 | for (aloop = root->inner; | |
2136 | aloop->inner != NULL; | |
2137 | aloop = aloop->inner) | |
2138 | { | |
2139 | if (preorder_p) | |
2140 | this->to_visit.quick_push (aloop->num); | |
2141 | continue; | |
2142 | } | |
2143 | ||
2144 | while (1) | |
2145 | { | |
2146 | gcc_assert (aloop != root); | |
2147 | if (from_innermost_p || aloop->inner == NULL) | |
2148 | this->to_visit.quick_push (aloop->num); | |
2149 | ||
2150 | if (aloop->next) | |
2151 | { | |
2152 | for (aloop = aloop->next; | |
2153 | aloop->inner != NULL; | |
2154 | aloop = aloop->inner) | |
2155 | { | |
2156 | if (preorder_p) | |
2157 | this->to_visit.quick_push (aloop->num); | |
2158 | continue; | |
2159 | } | |
2160 | } | |
2161 | else if (loop_outer (aloop) == root) | |
2162 | break; | |
2163 | else | |
2164 | aloop = loop_outer (aloop); | |
2165 | } | |
2166 | ||
2167 | /* When visiting from innermost, we need to consider root here | |
2168 | since the previous while loop doesn't handle it. */ | |
2169 | if (from_innermost_p && flags & LI_INCLUDE_ROOT) | |
2170 | this->to_visit.quick_push (root->num); | |
2171 | } | |
2172 |