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7d23383d | 1 | /* Loop invariant motion. |
fbd26352 | 2 | Copyright (C) 2003-2019 Free Software Foundation, Inc. |
48e1416a | 3 | |
7d23383d | 4 | This file is part of GCC. |
48e1416a | 5 | |
7d23383d | 6 | GCC is free software; you can redistribute it and/or modify it |
7 | under the terms of the GNU General Public License as published by the | |
8c4c00c1 | 8 | Free Software Foundation; either version 3, or (at your option) any |
7d23383d | 9 | later version. |
48e1416a | 10 | |
7d23383d | 11 | GCC is distributed in the hope that it will be useful, but WITHOUT |
12 | ANY 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. | |
48e1416a | 15 | |
7d23383d | 16 | You should have received a copy of the GNU General Public License |
8c4c00c1 | 17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
7d23383d | 19 | |
20 | #include "config.h" | |
21 | #include "system.h" | |
22 | #include "coretypes.h" | |
9ef16211 | 23 | #include "backend.h" |
7d23383d | 24 | #include "tree.h" |
9ef16211 | 25 | #include "gimple.h" |
7c29e30e | 26 | #include "cfghooks.h" |
27 | #include "tree-pass.h" | |
9ef16211 | 28 | #include "ssa.h" |
7c29e30e | 29 | #include "gimple-pretty-print.h" |
b20a8bb4 | 30 | #include "fold-const.h" |
94ea8568 | 31 | #include "cfganal.h" |
bc61cadb | 32 | #include "tree-eh.h" |
a8783bee | 33 | #include "gimplify.h" |
dcf1a1ec | 34 | #include "gimple-iterator.h" |
073c1fd5 | 35 | #include "tree-cfg.h" |
05d9c18a | 36 | #include "tree-ssa-loop-manip.h" |
073c1fd5 | 37 | #include "tree-ssa-loop.h" |
38 | #include "tree-into-ssa.h" | |
7d23383d | 39 | #include "cfgloop.h" |
40 | #include "domwalk.h" | |
41 | #include "params.h" | |
063a8bce | 42 | #include "tree-affine.h" |
a973ed42 | 43 | #include "tree-ssa-propagate.h" |
e797f49f | 44 | #include "trans-mem.h" |
f6a34e3f | 45 | #include "gimple-fold.h" |
b11dc37d | 46 | #include "tree-scalar-evolution.h" |
5b9b62c9 | 47 | #include "tree-ssa-loop-niter.h" |
1b94b295 | 48 | #include "alias.h" |
49 | #include "builtins.h" | |
50 | #include "tree-dfa.h" | |
7d23383d | 51 | |
ca53beb1 | 52 | /* TODO: Support for predicated code motion. I.e. |
53 | ||
54 | while (1) | |
55 | { | |
56 | if (cond) | |
57 | { | |
58 | a = inv; | |
59 | something; | |
60 | } | |
61 | } | |
62 | ||
61025ec0 | 63 | Where COND and INV are invariants, but evaluating INV may trap or be |
ca53beb1 | 64 | invalid from some other reason if !COND. This may be transformed to |
65 | ||
66 | if (cond) | |
67 | a = inv; | |
68 | while (1) | |
69 | { | |
70 | if (cond) | |
71 | something; | |
72 | } */ | |
73 | ||
7d23383d | 74 | /* The auxiliary data kept for each statement. */ |
75 | ||
76 | struct lim_aux_data | |
77 | { | |
78 | struct loop *max_loop; /* The outermost loop in that the statement | |
79 | is invariant. */ | |
80 | ||
81 | struct loop *tgt_loop; /* The loop out of that we want to move the | |
82 | invariant. */ | |
83 | ||
84 | struct loop *always_executed_in; | |
85 | /* The outermost loop for that we are sure | |
86 | the statement is executed if the loop | |
87 | is entered. */ | |
88 | ||
7d23383d | 89 | unsigned cost; /* Cost of the computation performed by the |
90 | statement. */ | |
91 | ||
735d8b51 | 92 | unsigned ref; /* The simple_mem_ref in this stmt or 0. */ |
93 | ||
94 | vec<gimple *> depends; /* Vector of statements that must be also | |
a2c22c0d | 95 | hoisted out of the loop when this statement |
96 | is hoisted; i.e. those that define the | |
97 | operands of the statement and are inside of | |
98 | the MAX_LOOP loop. */ | |
7d23383d | 99 | }; |
100 | ||
75a70cf9 | 101 | /* Maps statements to their lim_aux_data. */ |
102 | ||
42acab1c | 103 | static hash_map<gimple *, lim_aux_data *> *lim_aux_data_map; |
7d23383d | 104 | |
063a8bce | 105 | /* Description of a memory reference location. */ |
7d23383d | 106 | |
4a7ff262 | 107 | struct mem_ref_loc |
7d23383d | 108 | { |
109 | tree *ref; /* The reference itself. */ | |
42acab1c | 110 | gimple *stmt; /* The statement in that it occurs. */ |
4a7ff262 | 111 | }; |
063a8bce | 112 | |
063a8bce | 113 | |
063a8bce | 114 | /* Description of a memory reference. */ |
115 | ||
4a7ff262 | 116 | struct im_mem_ref |
55a03692 | 117 | { |
1b94b295 | 118 | unsigned id : 31; /* ID assigned to the memory reference |
063a8bce | 119 | (its index in memory_accesses.refs_list) */ |
1b94b295 | 120 | unsigned ref_canonical : 1; /* Whether mem.ref was canonicalized. */ |
55a03692 | 121 | hashval_t hash; /* Its hash value. */ |
09f4cf62 | 122 | |
123 | /* The memory access itself and associated caching of alias-oracle | |
124 | query meta-data. */ | |
125 | ao_ref mem; | |
126 | ||
3e48928c | 127 | bitmap stored; /* The set of loops in that this memory location |
063a8bce | 128 | is stored to. */ |
3e48928c | 129 | vec<mem_ref_loc> accesses_in_loop; |
063a8bce | 130 | /* The locations of the accesses. Vector |
131 | indexed by the loop number. */ | |
063a8bce | 132 | |
133 | /* The following sets are computed on demand. We keep both set and | |
134 | its complement, so that we know whether the information was | |
135 | already computed or not. */ | |
feba4360 | 136 | bitmap_head indep_loop; /* The set of loops in that the memory |
063a8bce | 137 | reference is independent, meaning: |
138 | If it is stored in the loop, this store | |
139 | is independent on all other loads and | |
140 | stores. | |
141 | If it is only loaded, then it is independent | |
142 | on all stores in the loop. */ | |
feba4360 | 143 | bitmap_head dep_loop; /* The complement of INDEP_LOOP. */ |
4a7ff262 | 144 | }; |
063a8bce | 145 | |
8f9829e8 | 146 | /* We use two bits per loop in the ref->{in,}dep_loop bitmaps, the first |
147 | to record (in)dependence against stores in the loop and its subloops, the | |
148 | second to record (in)dependence against all references in the loop | |
149 | and its subloops. */ | |
150 | #define LOOP_DEP_BIT(loopnum, storedp) (2 * (loopnum) + (storedp ? 1 : 0)) | |
063a8bce | 151 | |
3e871d4d | 152 | /* Mem_ref hashtable helpers. */ |
153 | ||
770ff93b | 154 | struct mem_ref_hasher : nofree_ptr_hash <im_mem_ref> |
3e871d4d | 155 | { |
1b94b295 | 156 | typedef ao_ref *compare_type; |
9969c043 | 157 | static inline hashval_t hash (const im_mem_ref *); |
1b94b295 | 158 | static inline bool equal (const im_mem_ref *, const ao_ref *); |
3e871d4d | 159 | }; |
160 | ||
1ada9901 | 161 | /* A hash function for struct im_mem_ref object OBJ. */ |
3e871d4d | 162 | |
163 | inline hashval_t | |
9969c043 | 164 | mem_ref_hasher::hash (const im_mem_ref *mem) |
3e871d4d | 165 | { |
166 | return mem->hash; | |
167 | } | |
168 | ||
1ada9901 | 169 | /* An equality function for struct im_mem_ref object MEM1 with |
3e871d4d | 170 | memory reference OBJ2. */ |
171 | ||
172 | inline bool | |
1b94b295 | 173 | mem_ref_hasher::equal (const im_mem_ref *mem1, const ao_ref *obj2) |
174 | { | |
175 | if (obj2->max_size_known_p ()) | |
176 | return (operand_equal_p (mem1->mem.base, obj2->base, 0) | |
177 | && known_eq (mem1->mem.offset, obj2->offset) | |
178 | && known_eq (mem1->mem.size, obj2->size) | |
179 | && known_eq (mem1->mem.max_size, obj2->max_size) | |
180 | && mem1->mem.volatile_p == obj2->volatile_p | |
181 | && mem1->mem.ref_alias_set == obj2->ref_alias_set | |
182 | && types_compatible_p (TREE_TYPE (mem1->mem.ref), | |
183 | TREE_TYPE (obj2->ref))); | |
184 | else | |
185 | return operand_equal_p (mem1->mem.ref, obj2->ref, 0); | |
3e871d4d | 186 | } |
063a8bce | 187 | |
063a8bce | 188 | |
189 | /* Description of memory accesses in loops. */ | |
190 | ||
191 | static struct | |
192 | { | |
193 | /* The hash table of memory references accessed in loops. */ | |
c1f445d2 | 194 | hash_table<mem_ref_hasher> *refs; |
063a8bce | 195 | |
196 | /* The list of memory references. */ | |
4a7ff262 | 197 | vec<im_mem_ref *> refs_list; |
063a8bce | 198 | |
199 | /* The set of memory references accessed in each loop. */ | |
feba4360 | 200 | vec<bitmap_head> refs_in_loop; |
063a8bce | 201 | |
8f9829e8 | 202 | /* The set of memory references stored in each loop. */ |
feba4360 | 203 | vec<bitmap_head> refs_stored_in_loop; |
8f9829e8 | 204 | |
8f9829e8 | 205 | /* The set of memory references stored in each loop, including subloops . */ |
feba4360 | 206 | vec<bitmap_head> all_refs_stored_in_loop; |
063a8bce | 207 | |
208 | /* Cache for expanding memory addresses. */ | |
5f8841a5 | 209 | hash_map<tree, name_expansion *> *ttae_cache; |
063a8bce | 210 | } memory_accesses; |
211 | ||
4fb07d00 | 212 | /* Obstack for the bitmaps in the above data structures. */ |
213 | static bitmap_obstack lim_bitmap_obstack; | |
3e48928c | 214 | static obstack mem_ref_obstack; |
4fb07d00 | 215 | |
23298f15 | 216 | static bool ref_indep_loop_p (struct loop *, im_mem_ref *); |
60b209bc | 217 | static bool ref_always_accessed_p (struct loop *, im_mem_ref *, bool); |
7d23383d | 218 | |
219 | /* Minimum cost of an expensive expression. */ | |
220 | #define LIM_EXPENSIVE ((unsigned) PARAM_VALUE (PARAM_LIM_EXPENSIVE)) | |
221 | ||
2fd20c29 | 222 | /* The outermost loop for which execution of the header guarantees that the |
7d23383d | 223 | block will be executed. */ |
224 | #define ALWAYS_EXECUTED_IN(BB) ((struct loop *) (BB)->aux) | |
2fd20c29 | 225 | #define SET_ALWAYS_EXECUTED_IN(BB, VAL) ((BB)->aux = (void *) (VAL)) |
7d23383d | 226 | |
04911505 | 227 | /* ID of the shared unanalyzable mem. */ |
228 | #define UNANALYZABLE_MEM_ID 0 | |
229 | ||
0766b2c0 | 230 | /* Whether the reference was analyzable. */ |
04911505 | 231 | #define MEM_ANALYZABLE(REF) ((REF)->id != UNANALYZABLE_MEM_ID) |
0766b2c0 | 232 | |
75a70cf9 | 233 | static struct lim_aux_data * |
42acab1c | 234 | init_lim_data (gimple *stmt) |
75a70cf9 | 235 | { |
06ecf488 | 236 | lim_aux_data *p = XCNEW (struct lim_aux_data); |
237 | lim_aux_data_map->put (stmt, p); | |
75a70cf9 | 238 | |
06ecf488 | 239 | return p; |
75a70cf9 | 240 | } |
241 | ||
242 | static struct lim_aux_data * | |
42acab1c | 243 | get_lim_data (gimple *stmt) |
75a70cf9 | 244 | { |
06ecf488 | 245 | lim_aux_data **p = lim_aux_data_map->get (stmt); |
75a70cf9 | 246 | if (!p) |
247 | return NULL; | |
248 | ||
06ecf488 | 249 | return *p; |
75a70cf9 | 250 | } |
251 | ||
252 | /* Releases the memory occupied by DATA. */ | |
253 | ||
254 | static void | |
255 | free_lim_aux_data (struct lim_aux_data *data) | |
256 | { | |
9af5ce0c | 257 | data->depends.release (); |
75a70cf9 | 258 | free (data); |
259 | } | |
260 | ||
261 | static void | |
42acab1c | 262 | clear_lim_data (gimple *stmt) |
75a70cf9 | 263 | { |
06ecf488 | 264 | lim_aux_data **p = lim_aux_data_map->get (stmt); |
75a70cf9 | 265 | if (!p) |
266 | return; | |
267 | ||
06ecf488 | 268 | free_lim_aux_data (*p); |
75a70cf9 | 269 | *p = NULL; |
270 | } | |
271 | ||
48e1416a | 272 | |
f86b328b | 273 | /* The possibilities of statement movement. */ |
274 | enum move_pos | |
275 | { | |
276 | MOVE_IMPOSSIBLE, /* No movement -- side effect expression. */ | |
277 | MOVE_PRESERVE_EXECUTION, /* Must not cause the non-executed statement | |
278 | become executed -- memory accesses, ... */ | |
279 | MOVE_POSSIBLE /* Unlimited movement. */ | |
280 | }; | |
aed164c3 | 281 | |
7d23383d | 282 | |
283 | /* If it is possible to hoist the statement STMT unconditionally, | |
284 | returns MOVE_POSSIBLE. | |
285 | If it is possible to hoist the statement STMT, but we must avoid making | |
286 | it executed if it would not be executed in the original program (e.g. | |
287 | because it may trap), return MOVE_PRESERVE_EXECUTION. | |
288 | Otherwise return MOVE_IMPOSSIBLE. */ | |
289 | ||
07c03fb0 | 290 | enum move_pos |
42acab1c | 291 | movement_possibility (gimple *stmt) |
7d23383d | 292 | { |
75a70cf9 | 293 | tree lhs; |
294 | enum move_pos ret = MOVE_POSSIBLE; | |
7d23383d | 295 | |
296 | if (flag_unswitch_loops | |
75a70cf9 | 297 | && gimple_code (stmt) == GIMPLE_COND) |
7d23383d | 298 | { |
299 | /* If we perform unswitching, force the operands of the invariant | |
300 | condition to be moved out of the loop. */ | |
7d23383d | 301 | return MOVE_POSSIBLE; |
302 | } | |
303 | ||
9bf0a3f9 | 304 | if (gimple_code (stmt) == GIMPLE_PHI |
305 | && gimple_phi_num_args (stmt) <= 2 | |
7c782c9b | 306 | && !virtual_operand_p (gimple_phi_result (stmt)) |
9bf0a3f9 | 307 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_phi_result (stmt))) |
308 | return MOVE_POSSIBLE; | |
309 | ||
75a70cf9 | 310 | if (gimple_get_lhs (stmt) == NULL_TREE) |
7d23383d | 311 | return MOVE_IMPOSSIBLE; |
312 | ||
dd277d48 | 313 | if (gimple_vdef (stmt)) |
063a8bce | 314 | return MOVE_IMPOSSIBLE; |
315 | ||
75a70cf9 | 316 | if (stmt_ends_bb_p (stmt) |
317 | || gimple_has_volatile_ops (stmt) | |
318 | || gimple_has_side_effects (stmt) | |
aac19106 | 319 | || stmt_could_throw_p (cfun, stmt)) |
7d23383d | 320 | return MOVE_IMPOSSIBLE; |
321 | ||
75a70cf9 | 322 | if (is_gimple_call (stmt)) |
ca53beb1 | 323 | { |
324 | /* While pure or const call is guaranteed to have no side effects, we | |
325 | cannot move it arbitrarily. Consider code like | |
326 | ||
327 | char *s = something (); | |
328 | ||
329 | while (1) | |
330 | { | |
331 | if (s) | |
332 | t = strlen (s); | |
333 | else | |
334 | t = 0; | |
335 | } | |
336 | ||
337 | Here the strlen call cannot be moved out of the loop, even though | |
338 | s is invariant. In addition to possibly creating a call with | |
339 | invalid arguments, moving out a function call that is not executed | |
340 | may cause performance regressions in case the call is costly and | |
341 | not executed at all. */ | |
75a70cf9 | 342 | ret = MOVE_PRESERVE_EXECUTION; |
343 | lhs = gimple_call_lhs (stmt); | |
ca53beb1 | 344 | } |
75a70cf9 | 345 | else if (is_gimple_assign (stmt)) |
346 | lhs = gimple_assign_lhs (stmt); | |
347 | else | |
348 | return MOVE_IMPOSSIBLE; | |
349 | ||
350 | if (TREE_CODE (lhs) == SSA_NAME | |
351 | && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) | |
352 | return MOVE_IMPOSSIBLE; | |
353 | ||
354 | if (TREE_CODE (lhs) != SSA_NAME | |
355 | || gimple_could_trap_p (stmt)) | |
356 | return MOVE_PRESERVE_EXECUTION; | |
357 | ||
de60f90c | 358 | /* Non local loads in a transaction cannot be hoisted out. Well, |
359 | unless the load happens on every path out of the loop, but we | |
360 | don't take this into account yet. */ | |
361 | if (flag_tm | |
362 | && gimple_in_transaction (stmt) | |
363 | && gimple_assign_single_p (stmt)) | |
364 | { | |
365 | tree rhs = gimple_assign_rhs1 (stmt); | |
366 | if (DECL_P (rhs) && is_global_var (rhs)) | |
367 | { | |
368 | if (dump_file) | |
369 | { | |
370 | fprintf (dump_file, "Cannot hoist conditional load of "); | |
371 | print_generic_expr (dump_file, rhs, TDF_SLIM); | |
372 | fprintf (dump_file, " because it is in a transaction.\n"); | |
373 | } | |
374 | return MOVE_IMPOSSIBLE; | |
375 | } | |
376 | } | |
377 | ||
75a70cf9 | 378 | return ret; |
7d23383d | 379 | } |
380 | ||
381 | /* Suppose that operand DEF is used inside the LOOP. Returns the outermost | |
91275768 | 382 | loop to that we could move the expression using DEF if it did not have |
7d23383d | 383 | other operands, i.e. the outermost loop enclosing LOOP in that the value |
384 | of DEF is invariant. */ | |
385 | ||
386 | static struct loop * | |
387 | outermost_invariant_loop (tree def, struct loop *loop) | |
388 | { | |
42acab1c | 389 | gimple *def_stmt; |
7d23383d | 390 | basic_block def_bb; |
391 | struct loop *max_loop; | |
75a70cf9 | 392 | struct lim_aux_data *lim_data; |
7d23383d | 393 | |
75a70cf9 | 394 | if (!def) |
7d23383d | 395 | return superloop_at_depth (loop, 1); |
396 | ||
75a70cf9 | 397 | if (TREE_CODE (def) != SSA_NAME) |
398 | { | |
399 | gcc_assert (is_gimple_min_invariant (def)); | |
400 | return superloop_at_depth (loop, 1); | |
401 | } | |
402 | ||
7d23383d | 403 | def_stmt = SSA_NAME_DEF_STMT (def); |
75a70cf9 | 404 | def_bb = gimple_bb (def_stmt); |
7d23383d | 405 | if (!def_bb) |
406 | return superloop_at_depth (loop, 1); | |
407 | ||
408 | max_loop = find_common_loop (loop, def_bb->loop_father); | |
409 | ||
75a70cf9 | 410 | lim_data = get_lim_data (def_stmt); |
411 | if (lim_data != NULL && lim_data->max_loop != NULL) | |
7d23383d | 412 | max_loop = find_common_loop (max_loop, |
75a70cf9 | 413 | loop_outer (lim_data->max_loop)); |
7d23383d | 414 | if (max_loop == loop) |
415 | return NULL; | |
9e3536f4 | 416 | max_loop = superloop_at_depth (loop, loop_depth (max_loop) + 1); |
7d23383d | 417 | |
418 | return max_loop; | |
419 | } | |
420 | ||
7d23383d | 421 | /* DATA is a structure containing information associated with a statement |
422 | inside LOOP. DEF is one of the operands of this statement. | |
48e1416a | 423 | |
7d23383d | 424 | Find the outermost loop enclosing LOOP in that value of DEF is invariant |
425 | and record this in DATA->max_loop field. If DEF itself is defined inside | |
426 | this loop as well (i.e. we need to hoist it out of the loop if we want | |
427 | to hoist the statement represented by DATA), record the statement in that | |
428 | DEF is defined to the DATA->depends list. Additionally if ADD_COST is true, | |
429 | add the cost of the computation of DEF to the DATA->cost. | |
48e1416a | 430 | |
7d23383d | 431 | If DEF is not invariant in LOOP, return false. Otherwise return TRUE. */ |
432 | ||
433 | static bool | |
434 | add_dependency (tree def, struct lim_aux_data *data, struct loop *loop, | |
435 | bool add_cost) | |
436 | { | |
42acab1c | 437 | gimple *def_stmt = SSA_NAME_DEF_STMT (def); |
75a70cf9 | 438 | basic_block def_bb = gimple_bb (def_stmt); |
7d23383d | 439 | struct loop *max_loop; |
75a70cf9 | 440 | struct lim_aux_data *def_data; |
7d23383d | 441 | |
442 | if (!def_bb) | |
443 | return true; | |
444 | ||
445 | max_loop = outermost_invariant_loop (def, loop); | |
446 | if (!max_loop) | |
447 | return false; | |
448 | ||
449 | if (flow_loop_nested_p (data->max_loop, max_loop)) | |
450 | data->max_loop = max_loop; | |
451 | ||
75a70cf9 | 452 | def_data = get_lim_data (def_stmt); |
453 | if (!def_data) | |
7d23383d | 454 | return true; |
455 | ||
456 | if (add_cost | |
457 | /* Only add the cost if the statement defining DEF is inside LOOP, | |
458 | i.e. if it is likely that by moving the invariants dependent | |
459 | on it, we will be able to avoid creating a new register for | |
460 | it (since it will be only used in these dependent invariants). */ | |
461 | && def_bb->loop_father == loop) | |
75a70cf9 | 462 | data->cost += def_data->cost; |
7d23383d | 463 | |
a2c22c0d | 464 | data->depends.safe_push (def_stmt); |
7d23383d | 465 | |
466 | return true; | |
467 | } | |
468 | ||
0766b2c0 | 469 | /* Returns an estimate for a cost of statement STMT. The values here |
470 | are just ad-hoc constants, similar to costs for inlining. */ | |
7d23383d | 471 | |
472 | static unsigned | |
42acab1c | 473 | stmt_cost (gimple *stmt) |
7d23383d | 474 | { |
7d23383d | 475 | /* Always try to create possibilities for unswitching. */ |
9bf0a3f9 | 476 | if (gimple_code (stmt) == GIMPLE_COND |
477 | || gimple_code (stmt) == GIMPLE_PHI) | |
7d23383d | 478 | return LIM_EXPENSIVE; |
479 | ||
0766b2c0 | 480 | /* We should be hoisting calls if possible. */ |
75a70cf9 | 481 | if (is_gimple_call (stmt)) |
7d23383d | 482 | { |
0766b2c0 | 483 | tree fndecl; |
7d23383d | 484 | |
485 | /* Unless the call is a builtin_constant_p; this always folds to a | |
486 | constant, so moving it is useless. */ | |
75a70cf9 | 487 | fndecl = gimple_call_fndecl (stmt); |
a0e9bfbb | 488 | if (fndecl && fndecl_built_in_p (fndecl, BUILT_IN_CONSTANT_P)) |
7d23383d | 489 | return 0; |
490 | ||
0766b2c0 | 491 | return LIM_EXPENSIVE; |
75a70cf9 | 492 | } |
493 | ||
0766b2c0 | 494 | /* Hoisting memory references out should almost surely be a win. */ |
495 | if (gimple_references_memory_p (stmt)) | |
496 | return LIM_EXPENSIVE; | |
497 | ||
75a70cf9 | 498 | if (gimple_code (stmt) != GIMPLE_ASSIGN) |
0766b2c0 | 499 | return 1; |
7d23383d | 500 | |
75a70cf9 | 501 | switch (gimple_assign_rhs_code (stmt)) |
502 | { | |
7d23383d | 503 | case MULT_EXPR: |
23da77dd | 504 | case WIDEN_MULT_EXPR: |
505 | case WIDEN_MULT_PLUS_EXPR: | |
506 | case WIDEN_MULT_MINUS_EXPR: | |
507 | case DOT_PROD_EXPR: | |
7d23383d | 508 | case TRUNC_DIV_EXPR: |
509 | case CEIL_DIV_EXPR: | |
510 | case FLOOR_DIV_EXPR: | |
511 | case ROUND_DIV_EXPR: | |
512 | case EXACT_DIV_EXPR: | |
513 | case CEIL_MOD_EXPR: | |
514 | case FLOOR_MOD_EXPR: | |
515 | case ROUND_MOD_EXPR: | |
516 | case TRUNC_MOD_EXPR: | |
fd544fc8 | 517 | case RDIV_EXPR: |
7d23383d | 518 | /* Division and multiplication are usually expensive. */ |
0766b2c0 | 519 | return LIM_EXPENSIVE; |
7d23383d | 520 | |
790963ba | 521 | case LSHIFT_EXPR: |
522 | case RSHIFT_EXPR: | |
23da77dd | 523 | case WIDEN_LSHIFT_EXPR: |
524 | case LROTATE_EXPR: | |
525 | case RROTATE_EXPR: | |
0766b2c0 | 526 | /* Shifts and rotates are usually expensive. */ |
527 | return LIM_EXPENSIVE; | |
528 | ||
529 | case CONSTRUCTOR: | |
530 | /* Make vector construction cost proportional to the number | |
531 | of elements. */ | |
532 | return CONSTRUCTOR_NELTS (gimple_assign_rhs1 (stmt)); | |
533 | ||
534 | case SSA_NAME: | |
535 | case PAREN_EXPR: | |
536 | /* Whether or not something is wrapped inside a PAREN_EXPR | |
537 | should not change move cost. Nor should an intermediate | |
538 | unpropagated SSA name copy. */ | |
539 | return 0; | |
790963ba | 540 | |
7d23383d | 541 | default: |
0766b2c0 | 542 | return 1; |
7d23383d | 543 | } |
7d23383d | 544 | } |
545 | ||
063a8bce | 546 | /* Finds the outermost loop between OUTER and LOOP in that the memory reference |
547 | REF is independent. If REF is not independent in LOOP, NULL is returned | |
548 | instead. */ | |
549 | ||
550 | static struct loop * | |
4a7ff262 | 551 | outermost_indep_loop (struct loop *outer, struct loop *loop, im_mem_ref *ref) |
063a8bce | 552 | { |
553 | struct loop *aloop; | |
554 | ||
3e48928c | 555 | if (ref->stored && bitmap_bit_p (ref->stored, loop->num)) |
063a8bce | 556 | return NULL; |
557 | ||
558 | for (aloop = outer; | |
559 | aloop != loop; | |
560 | aloop = superloop_at_depth (loop, loop_depth (aloop) + 1)) | |
3e48928c | 561 | if ((!ref->stored || !bitmap_bit_p (ref->stored, aloop->num)) |
23298f15 | 562 | && ref_indep_loop_p (aloop, ref)) |
063a8bce | 563 | return aloop; |
564 | ||
23298f15 | 565 | if (ref_indep_loop_p (loop, ref)) |
063a8bce | 566 | return loop; |
567 | else | |
568 | return NULL; | |
569 | } | |
570 | ||
571 | /* If there is a simple load or store to a memory reference in STMT, returns | |
f0b5f617 | 572 | the location of the memory reference, and sets IS_STORE according to whether |
063a8bce | 573 | it is a store or load. Otherwise, returns NULL. */ |
574 | ||
575 | static tree * | |
42acab1c | 576 | simple_mem_ref_in_stmt (gimple *stmt, bool *is_store) |
063a8bce | 577 | { |
6d7105fe | 578 | tree *lhs, *rhs; |
063a8bce | 579 | |
6d7105fe | 580 | /* Recognize SSA_NAME = MEM and MEM = (SSA_NAME | invariant) patterns. */ |
581 | if (!gimple_assign_single_p (stmt)) | |
063a8bce | 582 | return NULL; |
583 | ||
75a70cf9 | 584 | lhs = gimple_assign_lhs_ptr (stmt); |
6d7105fe | 585 | rhs = gimple_assign_rhs1_ptr (stmt); |
063a8bce | 586 | |
6d7105fe | 587 | if (TREE_CODE (*lhs) == SSA_NAME && gimple_vuse (stmt)) |
063a8bce | 588 | { |
063a8bce | 589 | *is_store = false; |
6d7105fe | 590 | return rhs; |
063a8bce | 591 | } |
6d7105fe | 592 | else if (gimple_vdef (stmt) |
593 | && (TREE_CODE (*rhs) == SSA_NAME || is_gimple_min_invariant (*rhs))) | |
063a8bce | 594 | { |
595 | *is_store = true; | |
596 | return lhs; | |
597 | } | |
598 | else | |
599 | return NULL; | |
600 | } | |
601 | ||
9bf0a3f9 | 602 | /* From a controlling predicate in DOM determine the arguments from |
603 | the PHI node PHI that are chosen if the predicate evaluates to | |
604 | true and false and store them to *TRUE_ARG_P and *FALSE_ARG_P if | |
605 | they are non-NULL. Returns true if the arguments can be determined, | |
606 | else return false. */ | |
607 | ||
608 | static bool | |
1a91d914 | 609 | extract_true_false_args_from_phi (basic_block dom, gphi *phi, |
9bf0a3f9 | 610 | tree *true_arg_p, tree *false_arg_p) |
611 | { | |
df10fba0 | 612 | edge te, fe; |
613 | if (! extract_true_false_controlled_edges (dom, gimple_bb (phi), | |
614 | &te, &fe)) | |
9bf0a3f9 | 615 | return false; |
616 | ||
617 | if (true_arg_p) | |
df10fba0 | 618 | *true_arg_p = PHI_ARG_DEF (phi, te->dest_idx); |
9bf0a3f9 | 619 | if (false_arg_p) |
df10fba0 | 620 | *false_arg_p = PHI_ARG_DEF (phi, fe->dest_idx); |
9bf0a3f9 | 621 | |
622 | return true; | |
623 | } | |
624 | ||
7d23383d | 625 | /* Determine the outermost loop to that it is possible to hoist a statement |
626 | STMT and store it to LIM_DATA (STMT)->max_loop. To do this we determine | |
627 | the outermost loop in that the value computed by STMT is invariant. | |
628 | If MUST_PRESERVE_EXEC is true, additionally choose such a loop that | |
629 | we preserve the fact whether STMT is executed. It also fills other related | |
630 | information to LIM_DATA (STMT). | |
48e1416a | 631 | |
7d23383d | 632 | The function returns false if STMT cannot be hoisted outside of the loop it |
633 | is defined in, and true otherwise. */ | |
634 | ||
635 | static bool | |
42acab1c | 636 | determine_max_movement (gimple *stmt, bool must_preserve_exec) |
7d23383d | 637 | { |
75a70cf9 | 638 | basic_block bb = gimple_bb (stmt); |
7d23383d | 639 | struct loop *loop = bb->loop_father; |
640 | struct loop *level; | |
75a70cf9 | 641 | struct lim_aux_data *lim_data = get_lim_data (stmt); |
43daa21e | 642 | tree val; |
643 | ssa_op_iter iter; | |
48e1416a | 644 | |
7d23383d | 645 | if (must_preserve_exec) |
646 | level = ALWAYS_EXECUTED_IN (bb); | |
647 | else | |
648 | level = superloop_at_depth (loop, 1); | |
649 | lim_data->max_loop = level; | |
650 | ||
1a91d914 | 651 | if (gphi *phi = dyn_cast <gphi *> (stmt)) |
9bf0a3f9 | 652 | { |
653 | use_operand_p use_p; | |
654 | unsigned min_cost = UINT_MAX; | |
655 | unsigned total_cost = 0; | |
656 | struct lim_aux_data *def_data; | |
657 | ||
658 | /* We will end up promoting dependencies to be unconditionally | |
659 | evaluated. For this reason the PHI cost (and thus the | |
660 | cost we remove from the loop by doing the invariant motion) | |
661 | is that of the cheapest PHI argument dependency chain. */ | |
1a91d914 | 662 | FOR_EACH_PHI_ARG (use_p, phi, iter, SSA_OP_USE) |
9bf0a3f9 | 663 | { |
664 | val = USE_FROM_PTR (use_p); | |
413fb820 | 665 | |
9bf0a3f9 | 666 | if (TREE_CODE (val) != SSA_NAME) |
413fb820 | 667 | { |
668 | /* Assign const 1 to constants. */ | |
669 | min_cost = MIN (min_cost, 1); | |
670 | total_cost += 1; | |
671 | continue; | |
672 | } | |
9bf0a3f9 | 673 | if (!add_dependency (val, lim_data, loop, false)) |
674 | return false; | |
07f7799f | 675 | |
42acab1c | 676 | gimple *def_stmt = SSA_NAME_DEF_STMT (val); |
07f7799f | 677 | if (gimple_bb (def_stmt) |
678 | && gimple_bb (def_stmt)->loop_father == loop) | |
9bf0a3f9 | 679 | { |
07f7799f | 680 | def_data = get_lim_data (def_stmt); |
681 | if (def_data) | |
682 | { | |
683 | min_cost = MIN (min_cost, def_data->cost); | |
684 | total_cost += def_data->cost; | |
685 | } | |
9bf0a3f9 | 686 | } |
687 | } | |
688 | ||
07f7799f | 689 | min_cost = MIN (min_cost, total_cost); |
9bf0a3f9 | 690 | lim_data->cost += min_cost; |
691 | ||
1a91d914 | 692 | if (gimple_phi_num_args (phi) > 1) |
9bf0a3f9 | 693 | { |
694 | basic_block dom = get_immediate_dominator (CDI_DOMINATORS, bb); | |
42acab1c | 695 | gimple *cond; |
9bf0a3f9 | 696 | if (gsi_end_p (gsi_last_bb (dom))) |
697 | return false; | |
698 | cond = gsi_stmt (gsi_last_bb (dom)); | |
699 | if (gimple_code (cond) != GIMPLE_COND) | |
700 | return false; | |
701 | /* Verify that this is an extended form of a diamond and | |
702 | the PHI arguments are completely controlled by the | |
703 | predicate in DOM. */ | |
1a91d914 | 704 | if (!extract_true_false_args_from_phi (dom, phi, NULL, NULL)) |
9bf0a3f9 | 705 | return false; |
706 | ||
707 | /* Fold in dependencies and cost of the condition. */ | |
708 | FOR_EACH_SSA_TREE_OPERAND (val, cond, iter, SSA_OP_USE) | |
709 | { | |
710 | if (!add_dependency (val, lim_data, loop, false)) | |
711 | return false; | |
712 | def_data = get_lim_data (SSA_NAME_DEF_STMT (val)); | |
713 | if (def_data) | |
47578cb1 | 714 | lim_data->cost += def_data->cost; |
9bf0a3f9 | 715 | } |
716 | ||
717 | /* We want to avoid unconditionally executing very expensive | |
718 | operations. As costs for our dependencies cannot be | |
719 | negative just claim we are not invariand for this case. | |
720 | We also are not sure whether the control-flow inside the | |
721 | loop will vanish. */ | |
722 | if (total_cost - min_cost >= 2 * LIM_EXPENSIVE | |
723 | && !(min_cost != 0 | |
724 | && total_cost / min_cost <= 2)) | |
725 | return false; | |
726 | ||
727 | /* Assume that the control-flow in the loop will vanish. | |
728 | ??? We should verify this and not artificially increase | |
729 | the cost if that is not the case. */ | |
730 | lim_data->cost += stmt_cost (stmt); | |
731 | } | |
732 | ||
733 | return true; | |
734 | } | |
735 | else | |
736 | FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_USE) | |
737 | if (!add_dependency (val, lim_data, loop, true)) | |
738 | return false; | |
7d23383d | 739 | |
dd277d48 | 740 | if (gimple_vuse (stmt)) |
063a8bce | 741 | { |
735d8b51 | 742 | im_mem_ref *ref |
743 | = lim_data ? memory_accesses.refs_list[lim_data->ref] : NULL; | |
744 | if (ref | |
745 | && MEM_ANALYZABLE (ref)) | |
063a8bce | 746 | { |
735d8b51 | 747 | lim_data->max_loop = outermost_indep_loop (lim_data->max_loop, |
748 | loop, ref); | |
063a8bce | 749 | if (!lim_data->max_loop) |
750 | return false; | |
751 | } | |
735d8b51 | 752 | else if (! add_dependency (gimple_vuse (stmt), lim_data, loop, false)) |
753 | return false; | |
063a8bce | 754 | } |
7d23383d | 755 | |
756 | lim_data->cost += stmt_cost (stmt); | |
757 | ||
758 | return true; | |
759 | } | |
760 | ||
761 | /* Suppose that some statement in ORIG_LOOP is hoisted to the loop LEVEL, | |
762 | and that one of the operands of this statement is computed by STMT. | |
763 | Ensure that STMT (together with all the statements that define its | |
764 | operands) is hoisted at least out of the loop LEVEL. */ | |
765 | ||
766 | static void | |
42acab1c | 767 | set_level (gimple *stmt, struct loop *orig_loop, struct loop *level) |
7d23383d | 768 | { |
75a70cf9 | 769 | struct loop *stmt_loop = gimple_bb (stmt)->loop_father; |
75a70cf9 | 770 | struct lim_aux_data *lim_data; |
42acab1c | 771 | gimple *dep_stmt; |
a2c22c0d | 772 | unsigned i; |
7d23383d | 773 | |
774 | stmt_loop = find_common_loop (orig_loop, stmt_loop); | |
75a70cf9 | 775 | lim_data = get_lim_data (stmt); |
776 | if (lim_data != NULL && lim_data->tgt_loop != NULL) | |
7d23383d | 777 | stmt_loop = find_common_loop (stmt_loop, |
75a70cf9 | 778 | loop_outer (lim_data->tgt_loop)); |
7d23383d | 779 | if (flow_loop_nested_p (stmt_loop, level)) |
780 | return; | |
781 | ||
75a70cf9 | 782 | gcc_assert (level == lim_data->max_loop |
783 | || flow_loop_nested_p (lim_data->max_loop, level)); | |
7d23383d | 784 | |
75a70cf9 | 785 | lim_data->tgt_loop = level; |
a2c22c0d | 786 | FOR_EACH_VEC_ELT (lim_data->depends, i, dep_stmt) |
787 | set_level (dep_stmt, orig_loop, level); | |
7d23383d | 788 | } |
789 | ||
790 | /* Determines an outermost loop from that we want to hoist the statement STMT. | |
791 | For now we chose the outermost possible loop. TODO -- use profiling | |
792 | information to set it more sanely. */ | |
793 | ||
794 | static void | |
42acab1c | 795 | set_profitable_level (gimple *stmt) |
7d23383d | 796 | { |
75a70cf9 | 797 | set_level (stmt, gimple_bb (stmt)->loop_father, get_lim_data (stmt)->max_loop); |
7d23383d | 798 | } |
799 | ||
75a70cf9 | 800 | /* Returns true if STMT is a call that has side effects. */ |
7d23383d | 801 | |
802 | static bool | |
42acab1c | 803 | nonpure_call_p (gimple *stmt) |
7d23383d | 804 | { |
75a70cf9 | 805 | if (gimple_code (stmt) != GIMPLE_CALL) |
7d23383d | 806 | return false; |
807 | ||
75a70cf9 | 808 | return gimple_has_side_effects (stmt); |
7d23383d | 809 | } |
810 | ||
790963ba | 811 | /* Rewrite a/b to a*(1/b). Return the invariant stmt to process. */ |
812 | ||
42acab1c | 813 | static gimple * |
75a70cf9 | 814 | rewrite_reciprocal (gimple_stmt_iterator *bsi) |
790963ba | 815 | { |
1a91d914 | 816 | gassign *stmt, *stmt1, *stmt2; |
03d37e4e | 817 | tree name, lhs, type; |
193b8a15 | 818 | tree real_one; |
688ff29b | 819 | gimple_stmt_iterator gsi; |
790963ba | 820 | |
1a91d914 | 821 | stmt = as_a <gassign *> (gsi_stmt (*bsi)); |
75a70cf9 | 822 | lhs = gimple_assign_lhs (stmt); |
823 | type = TREE_TYPE (lhs); | |
790963ba | 824 | |
74560f89 | 825 | real_one = build_one_cst (type); |
790963ba | 826 | |
03d37e4e | 827 | name = make_temp_ssa_name (type, NULL, "reciptmp"); |
e9cf809e | 828 | stmt1 = gimple_build_assign (name, RDIV_EXPR, real_one, |
829 | gimple_assign_rhs2 (stmt)); | |
830 | stmt2 = gimple_build_assign (lhs, MULT_EXPR, name, | |
831 | gimple_assign_rhs1 (stmt)); | |
790963ba | 832 | |
833 | /* Replace division stmt with reciprocal and multiply stmts. | |
834 | The multiply stmt is not invariant, so update iterator | |
835 | and avoid rescanning. */ | |
688ff29b | 836 | gsi = *bsi; |
837 | gsi_insert_before (bsi, stmt1, GSI_NEW_STMT); | |
838 | gsi_replace (&gsi, stmt2, true); | |
790963ba | 839 | |
840 | /* Continue processing with invariant reciprocal statement. */ | |
841 | return stmt1; | |
842 | } | |
843 | ||
844 | /* Check if the pattern at *BSI is a bittest of the form | |
845 | (A >> B) & 1 != 0 and in this case rewrite it to A & (1 << B) != 0. */ | |
846 | ||
42acab1c | 847 | static gimple * |
75a70cf9 | 848 | rewrite_bittest (gimple_stmt_iterator *bsi) |
790963ba | 849 | { |
1a91d914 | 850 | gassign *stmt; |
42acab1c | 851 | gimple *stmt1; |
1a91d914 | 852 | gassign *stmt2; |
42acab1c | 853 | gimple *use_stmt; |
1a91d914 | 854 | gcond *cond_stmt; |
03d37e4e | 855 | tree lhs, name, t, a, b; |
790963ba | 856 | use_operand_p use; |
857 | ||
1a91d914 | 858 | stmt = as_a <gassign *> (gsi_stmt (*bsi)); |
75a70cf9 | 859 | lhs = gimple_assign_lhs (stmt); |
790963ba | 860 | |
861 | /* Verify that the single use of lhs is a comparison against zero. */ | |
862 | if (TREE_CODE (lhs) != SSA_NAME | |
1a91d914 | 863 | || !single_imm_use (lhs, &use, &use_stmt)) |
790963ba | 864 | return stmt; |
1a91d914 | 865 | cond_stmt = dyn_cast <gcond *> (use_stmt); |
866 | if (!cond_stmt) | |
867 | return stmt; | |
868 | if (gimple_cond_lhs (cond_stmt) != lhs | |
869 | || (gimple_cond_code (cond_stmt) != NE_EXPR | |
870 | && gimple_cond_code (cond_stmt) != EQ_EXPR) | |
871 | || !integer_zerop (gimple_cond_rhs (cond_stmt))) | |
790963ba | 872 | return stmt; |
873 | ||
874 | /* Get at the operands of the shift. The rhs is TMP1 & 1. */ | |
75a70cf9 | 875 | stmt1 = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (stmt)); |
876 | if (gimple_code (stmt1) != GIMPLE_ASSIGN) | |
790963ba | 877 | return stmt; |
878 | ||
bef304b8 | 879 | /* There is a conversion in between possibly inserted by fold. */ |
d9659041 | 880 | if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt1))) |
790963ba | 881 | { |
75a70cf9 | 882 | t = gimple_assign_rhs1 (stmt1); |
790963ba | 883 | if (TREE_CODE (t) != SSA_NAME |
884 | || !has_single_use (t)) | |
885 | return stmt; | |
886 | stmt1 = SSA_NAME_DEF_STMT (t); | |
75a70cf9 | 887 | if (gimple_code (stmt1) != GIMPLE_ASSIGN) |
790963ba | 888 | return stmt; |
790963ba | 889 | } |
890 | ||
891 | /* Verify that B is loop invariant but A is not. Verify that with | |
892 | all the stmt walking we are still in the same loop. */ | |
75a70cf9 | 893 | if (gimple_assign_rhs_code (stmt1) != RSHIFT_EXPR |
894 | || loop_containing_stmt (stmt1) != loop_containing_stmt (stmt)) | |
895 | return stmt; | |
790963ba | 896 | |
75a70cf9 | 897 | a = gimple_assign_rhs1 (stmt1); |
898 | b = gimple_assign_rhs2 (stmt1); | |
899 | ||
900 | if (outermost_invariant_loop (b, loop_containing_stmt (stmt1)) != NULL | |
901 | && outermost_invariant_loop (a, loop_containing_stmt (stmt1)) == NULL) | |
902 | { | |
688ff29b | 903 | gimple_stmt_iterator rsi; |
904 | ||
790963ba | 905 | /* 1 << B */ |
790963ba | 906 | t = fold_build2 (LSHIFT_EXPR, TREE_TYPE (a), |
907 | build_int_cst (TREE_TYPE (a), 1), b); | |
03d37e4e | 908 | name = make_temp_ssa_name (TREE_TYPE (a), NULL, "shifttmp"); |
909 | stmt1 = gimple_build_assign (name, t); | |
790963ba | 910 | |
911 | /* A & (1 << B) */ | |
912 | t = fold_build2 (BIT_AND_EXPR, TREE_TYPE (a), a, name); | |
03d37e4e | 913 | name = make_temp_ssa_name (TREE_TYPE (a), NULL, "shifttmp"); |
914 | stmt2 = gimple_build_assign (name, t); | |
3de988b5 | 915 | |
916 | /* Replace the SSA_NAME we compare against zero. Adjust | |
917 | the type of zero accordingly. */ | |
27dc0bdf | 918 | SET_USE (use, name); |
1a91d914 | 919 | gimple_cond_set_rhs (cond_stmt, |
920 | build_int_cst_type (TREE_TYPE (name), | |
921 | 0)); | |
790963ba | 922 | |
688ff29b | 923 | /* Don't use gsi_replace here, none of the new assignments sets |
924 | the variable originally set in stmt. Move bsi to stmt1, and | |
925 | then remove the original stmt, so that we get a chance to | |
926 | retain debug info for it. */ | |
927 | rsi = *bsi; | |
928 | gsi_insert_before (bsi, stmt1, GSI_NEW_STMT); | |
929 | gsi_insert_before (&rsi, stmt2, GSI_SAME_STMT); | |
c7f66ec2 | 930 | gimple *to_release = gsi_stmt (rsi); |
688ff29b | 931 | gsi_remove (&rsi, true); |
c7f66ec2 | 932 | release_defs (to_release); |
790963ba | 933 | |
934 | return stmt1; | |
935 | } | |
936 | ||
937 | return stmt; | |
938 | } | |
939 | ||
54c91640 | 940 | /* For each statement determines the outermost loop in that it is invariant, |
941 | - statements on whose motion it depends and the cost of the computation. | |
942 | - This information is stored to the LIM_DATA structure associated with | |
943 | - each statement. */ | |
944 | class invariantness_dom_walker : public dom_walker | |
945 | { | |
946 | public: | |
947 | invariantness_dom_walker (cdi_direction direction) | |
948 | : dom_walker (direction) {} | |
949 | ||
96752458 | 950 | virtual edge before_dom_children (basic_block); |
54c91640 | 951 | }; |
790963ba | 952 | |
7d23383d | 953 | /* Determine the outermost loops in that statements in basic block BB are |
954 | invariant, and record them to the LIM_DATA associated with the statements. | |
54c91640 | 955 | Callback for dom_walker. */ |
7d23383d | 956 | |
96752458 | 957 | edge |
54c91640 | 958 | invariantness_dom_walker::before_dom_children (basic_block bb) |
7d23383d | 959 | { |
960 | enum move_pos pos; | |
75a70cf9 | 961 | gimple_stmt_iterator bsi; |
42acab1c | 962 | gimple *stmt; |
7d23383d | 963 | bool maybe_never = ALWAYS_EXECUTED_IN (bb) == NULL; |
964 | struct loop *outermost = ALWAYS_EXECUTED_IN (bb); | |
75a70cf9 | 965 | struct lim_aux_data *lim_data; |
7d23383d | 966 | |
9e3536f4 | 967 | if (!loop_outer (bb->loop_father)) |
96752458 | 968 | return NULL; |
7d23383d | 969 | |
970 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
971 | fprintf (dump_file, "Basic block %d (loop %d -- depth %d):\n\n", | |
9e3536f4 | 972 | bb->index, bb->loop_father->num, loop_depth (bb->loop_father)); |
7d23383d | 973 | |
9bf0a3f9 | 974 | /* Look at PHI nodes, but only if there is at most two. |
975 | ??? We could relax this further by post-processing the inserted | |
976 | code and transforming adjacent cond-exprs with the same predicate | |
977 | to control flow again. */ | |
978 | bsi = gsi_start_phis (bb); | |
979 | if (!gsi_end_p (bsi) | |
980 | && ((gsi_next (&bsi), gsi_end_p (bsi)) | |
981 | || (gsi_next (&bsi), gsi_end_p (bsi)))) | |
982 | for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
983 | { | |
984 | stmt = gsi_stmt (bsi); | |
985 | ||
986 | pos = movement_possibility (stmt); | |
987 | if (pos == MOVE_IMPOSSIBLE) | |
988 | continue; | |
989 | ||
735d8b51 | 990 | lim_data = get_lim_data (stmt); |
991 | if (! lim_data) | |
992 | lim_data = init_lim_data (stmt); | |
9bf0a3f9 | 993 | lim_data->always_executed_in = outermost; |
994 | ||
995 | if (!determine_max_movement (stmt, false)) | |
996 | { | |
997 | lim_data->max_loop = NULL; | |
998 | continue; | |
999 | } | |
1000 | ||
1001 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1002 | { | |
1ffa4346 | 1003 | print_gimple_stmt (dump_file, stmt, 2); |
9bf0a3f9 | 1004 | fprintf (dump_file, " invariant up to level %d, cost %d.\n\n", |
1005 | loop_depth (lim_data->max_loop), | |
1006 | lim_data->cost); | |
1007 | } | |
1008 | ||
1009 | if (lim_data->cost >= LIM_EXPENSIVE) | |
1010 | set_profitable_level (stmt); | |
1011 | } | |
1012 | ||
75a70cf9 | 1013 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
7d23383d | 1014 | { |
75a70cf9 | 1015 | stmt = gsi_stmt (bsi); |
7d23383d | 1016 | |
1017 | pos = movement_possibility (stmt); | |
1018 | if (pos == MOVE_IMPOSSIBLE) | |
1019 | { | |
1020 | if (nonpure_call_p (stmt)) | |
1021 | { | |
1022 | maybe_never = true; | |
1023 | outermost = NULL; | |
1024 | } | |
a973ed42 | 1025 | /* Make sure to note always_executed_in for stores to make |
1026 | store-motion work. */ | |
1027 | else if (stmt_makes_single_store (stmt)) | |
1028 | { | |
735d8b51 | 1029 | struct lim_aux_data *lim_data = get_lim_data (stmt); |
1030 | if (! lim_data) | |
1031 | lim_data = init_lim_data (stmt); | |
75a70cf9 | 1032 | lim_data->always_executed_in = outermost; |
a973ed42 | 1033 | } |
7d23383d | 1034 | continue; |
1035 | } | |
1036 | ||
75a70cf9 | 1037 | if (is_gimple_assign (stmt) |
1038 | && (get_gimple_rhs_class (gimple_assign_rhs_code (stmt)) | |
1039 | == GIMPLE_BINARY_RHS)) | |
63f88450 | 1040 | { |
75a70cf9 | 1041 | tree op0 = gimple_assign_rhs1 (stmt); |
1042 | tree op1 = gimple_assign_rhs2 (stmt); | |
1043 | struct loop *ol1 = outermost_invariant_loop (op1, | |
1044 | loop_containing_stmt (stmt)); | |
63f88450 | 1045 | |
1046 | /* If divisor is invariant, convert a/b to a*(1/b), allowing reciprocal | |
1047 | to be hoisted out of loop, saving expensive divide. */ | |
1048 | if (pos == MOVE_POSSIBLE | |
75a70cf9 | 1049 | && gimple_assign_rhs_code (stmt) == RDIV_EXPR |
63f88450 | 1050 | && flag_unsafe_math_optimizations |
1051 | && !flag_trapping_math | |
75a70cf9 | 1052 | && ol1 != NULL |
1053 | && outermost_invariant_loop (op0, ol1) == NULL) | |
63f88450 | 1054 | stmt = rewrite_reciprocal (&bsi); |
1055 | ||
1056 | /* If the shift count is invariant, convert (A >> B) & 1 to | |
1057 | A & (1 << B) allowing the bit mask to be hoisted out of the loop | |
1058 | saving an expensive shift. */ | |
1059 | if (pos == MOVE_POSSIBLE | |
75a70cf9 | 1060 | && gimple_assign_rhs_code (stmt) == BIT_AND_EXPR |
1061 | && integer_onep (op1) | |
1062 | && TREE_CODE (op0) == SSA_NAME | |
1063 | && has_single_use (op0)) | |
63f88450 | 1064 | stmt = rewrite_bittest (&bsi); |
1065 | } | |
fcee97ca | 1066 | |
735d8b51 | 1067 | lim_data = get_lim_data (stmt); |
1068 | if (! lim_data) | |
1069 | lim_data = init_lim_data (stmt); | |
75a70cf9 | 1070 | lim_data->always_executed_in = outermost; |
7d23383d | 1071 | |
1072 | if (maybe_never && pos == MOVE_PRESERVE_EXECUTION) | |
1073 | continue; | |
1074 | ||
1075 | if (!determine_max_movement (stmt, pos == MOVE_PRESERVE_EXECUTION)) | |
1076 | { | |
75a70cf9 | 1077 | lim_data->max_loop = NULL; |
7d23383d | 1078 | continue; |
1079 | } | |
1080 | ||
1081 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1082 | { | |
1ffa4346 | 1083 | print_gimple_stmt (dump_file, stmt, 2); |
7d23383d | 1084 | fprintf (dump_file, " invariant up to level %d, cost %d.\n\n", |
75a70cf9 | 1085 | loop_depth (lim_data->max_loop), |
1086 | lim_data->cost); | |
7d23383d | 1087 | } |
1088 | ||
75a70cf9 | 1089 | if (lim_data->cost >= LIM_EXPENSIVE) |
7d23383d | 1090 | set_profitable_level (stmt); |
1091 | } | |
96752458 | 1092 | return NULL; |
7d23383d | 1093 | } |
1094 | ||
7d23383d | 1095 | /* Hoist the statements in basic block BB out of the loops prescribed by |
91275768 | 1096 | data stored in LIM_DATA structures associated with each statement. Callback |
7d23383d | 1097 | for walk_dominator_tree. */ |
1098 | ||
2c7b2f88 | 1099 | unsigned int |
1100 | move_computations_worker (basic_block bb) | |
7d23383d | 1101 | { |
1102 | struct loop *level; | |
7d23383d | 1103 | unsigned cost = 0; |
75a70cf9 | 1104 | struct lim_aux_data *lim_data; |
2c7b2f88 | 1105 | unsigned int todo = 0; |
7d23383d | 1106 | |
9e3536f4 | 1107 | if (!loop_outer (bb->loop_father)) |
2c7b2f88 | 1108 | return todo; |
7d23383d | 1109 | |
1a91d914 | 1110 | for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); ) |
9bf0a3f9 | 1111 | { |
1a91d914 | 1112 | gassign *new_stmt; |
1113 | gphi *stmt = bsi.phi (); | |
9bf0a3f9 | 1114 | |
1115 | lim_data = get_lim_data (stmt); | |
1116 | if (lim_data == NULL) | |
1117 | { | |
1118 | gsi_next (&bsi); | |
1119 | continue; | |
1120 | } | |
1121 | ||
1122 | cost = lim_data->cost; | |
1123 | level = lim_data->tgt_loop; | |
1124 | clear_lim_data (stmt); | |
1125 | ||
1126 | if (!level) | |
1127 | { | |
1128 | gsi_next (&bsi); | |
1129 | continue; | |
1130 | } | |
1131 | ||
1132 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1133 | { | |
1134 | fprintf (dump_file, "Moving PHI node\n"); | |
1ffa4346 | 1135 | print_gimple_stmt (dump_file, stmt, 0); |
9bf0a3f9 | 1136 | fprintf (dump_file, "(cost %u) out of loop %d.\n\n", |
1137 | cost, level->num); | |
1138 | } | |
1139 | ||
1140 | if (gimple_phi_num_args (stmt) == 1) | |
1141 | { | |
1142 | tree arg = PHI_ARG_DEF (stmt, 0); | |
e9cf809e | 1143 | new_stmt = gimple_build_assign (gimple_phi_result (stmt), |
1144 | TREE_CODE (arg), arg); | |
9bf0a3f9 | 1145 | } |
1146 | else | |
1147 | { | |
1148 | basic_block dom = get_immediate_dominator (CDI_DOMINATORS, bb); | |
42acab1c | 1149 | gimple *cond = gsi_stmt (gsi_last_bb (dom)); |
9bf0a3f9 | 1150 | tree arg0 = NULL_TREE, arg1 = NULL_TREE, t; |
1151 | /* Get the PHI arguments corresponding to the true and false | |
1152 | edges of COND. */ | |
1153 | extract_true_false_args_from_phi (dom, stmt, &arg0, &arg1); | |
1154 | gcc_assert (arg0 && arg1); | |
1155 | t = build2 (gimple_cond_code (cond), boolean_type_node, | |
1156 | gimple_cond_lhs (cond), gimple_cond_rhs (cond)); | |
e9cf809e | 1157 | new_stmt = gimple_build_assign (gimple_phi_result (stmt), |
1158 | COND_EXPR, t, arg0, arg1); | |
2c7b2f88 | 1159 | todo |= TODO_cleanup_cfg; |
9bf0a3f9 | 1160 | } |
8e50a020 | 1161 | if (INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (new_stmt))) |
1162 | && (!ALWAYS_EXECUTED_IN (bb) | |
1163 | || (ALWAYS_EXECUTED_IN (bb) != level | |
1164 | && !flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
ccf6cffa | 1165 | { |
1166 | tree lhs = gimple_assign_lhs (new_stmt); | |
1167 | SSA_NAME_RANGE_INFO (lhs) = NULL; | |
ccf6cffa | 1168 | } |
9bf0a3f9 | 1169 | gsi_insert_on_edge (loop_preheader_edge (level), new_stmt); |
1170 | remove_phi_node (&bsi, false); | |
1171 | } | |
1172 | ||
1a91d914 | 1173 | for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); ) |
7d23383d | 1174 | { |
e70e8b13 | 1175 | edge e; |
1176 | ||
42acab1c | 1177 | gimple *stmt = gsi_stmt (bsi); |
7d23383d | 1178 | |
75a70cf9 | 1179 | lim_data = get_lim_data (stmt); |
1180 | if (lim_data == NULL) | |
7d23383d | 1181 | { |
75a70cf9 | 1182 | gsi_next (&bsi); |
7d23383d | 1183 | continue; |
1184 | } | |
1185 | ||
75a70cf9 | 1186 | cost = lim_data->cost; |
1187 | level = lim_data->tgt_loop; | |
1188 | clear_lim_data (stmt); | |
7d23383d | 1189 | |
1190 | if (!level) | |
1191 | { | |
75a70cf9 | 1192 | gsi_next (&bsi); |
7d23383d | 1193 | continue; |
1194 | } | |
1195 | ||
1196 | /* We do not really want to move conditionals out of the loop; we just | |
1197 | placed it here to force its operands to be moved if necessary. */ | |
75a70cf9 | 1198 | if (gimple_code (stmt) == GIMPLE_COND) |
7d23383d | 1199 | continue; |
1200 | ||
1201 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1202 | { | |
1203 | fprintf (dump_file, "Moving statement\n"); | |
1ffa4346 | 1204 | print_gimple_stmt (dump_file, stmt, 0); |
7d23383d | 1205 | fprintf (dump_file, "(cost %u) out of loop %d.\n\n", |
1206 | cost, level->num); | |
1207 | } | |
063a8bce | 1208 | |
e70e8b13 | 1209 | e = loop_preheader_edge (level); |
1210 | gcc_assert (!gimple_vdef (stmt)); | |
1211 | if (gimple_vuse (stmt)) | |
1212 | { | |
1213 | /* The new VUSE is the one from the virtual PHI in the loop | |
1214 | header or the one already present. */ | |
1a91d914 | 1215 | gphi_iterator gsi2; |
e70e8b13 | 1216 | for (gsi2 = gsi_start_phis (e->dest); |
1217 | !gsi_end_p (gsi2); gsi_next (&gsi2)) | |
1218 | { | |
1a91d914 | 1219 | gphi *phi = gsi2.phi (); |
7c782c9b | 1220 | if (virtual_operand_p (gimple_phi_result (phi))) |
e70e8b13 | 1221 | { |
1222 | gimple_set_vuse (stmt, PHI_ARG_DEF_FROM_EDGE (phi, e)); | |
1223 | break; | |
1224 | } | |
1225 | } | |
1226 | } | |
75a70cf9 | 1227 | gsi_remove (&bsi, false); |
8e50a020 | 1228 | if (gimple_has_lhs (stmt) |
1229 | && TREE_CODE (gimple_get_lhs (stmt)) == SSA_NAME | |
1230 | && INTEGRAL_TYPE_P (TREE_TYPE (gimple_get_lhs (stmt))) | |
1231 | && (!ALWAYS_EXECUTED_IN (bb) | |
1232 | || !(ALWAYS_EXECUTED_IN (bb) == level | |
1233 | || flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
ccf6cffa | 1234 | { |
1235 | tree lhs = gimple_get_lhs (stmt); | |
1236 | SSA_NAME_RANGE_INFO (lhs) = NULL; | |
ccf6cffa | 1237 | } |
bc228ba1 | 1238 | /* In case this is a stmt that is not unconditionally executed |
1239 | when the target loop header is executed and the stmt may | |
1240 | invoke undefined integer or pointer overflow rewrite it to | |
1241 | unsigned arithmetic. */ | |
1242 | if (is_gimple_assign (stmt) | |
1243 | && INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (stmt))) | |
1244 | && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (gimple_assign_lhs (stmt))) | |
1245 | && arith_code_with_undefined_signed_overflow | |
1246 | (gimple_assign_rhs_code (stmt)) | |
1247 | && (!ALWAYS_EXECUTED_IN (bb) | |
1248 | || !(ALWAYS_EXECUTED_IN (bb) == level | |
1249 | || flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
1250 | gsi_insert_seq_on_edge (e, rewrite_to_defined_overflow (stmt)); | |
1251 | else | |
1252 | gsi_insert_on_edge (e, stmt); | |
7d23383d | 1253 | } |
2c7b2f88 | 1254 | |
1255 | return todo; | |
7d23383d | 1256 | } |
1257 | ||
1258 | /* Hoist the statements out of the loops prescribed by data stored in | |
91275768 | 1259 | LIM_DATA structures associated with each statement.*/ |
7d23383d | 1260 | |
9bf0a3f9 | 1261 | static unsigned int |
7d23383d | 1262 | move_computations (void) |
1263 | { | |
2c7b2f88 | 1264 | int *rpo = XNEWVEC (int, last_basic_block_for_fn (cfun)); |
1265 | int n = pre_and_rev_post_order_compute_fn (cfun, NULL, rpo, false); | |
1266 | unsigned todo = 0; | |
1267 | ||
1268 | for (int i = 0; i < n; ++i) | |
1269 | todo |= move_computations_worker (BASIC_BLOCK_FOR_FN (cfun, rpo[i])); | |
1270 | ||
1271 | free (rpo); | |
7d23383d | 1272 | |
75a70cf9 | 1273 | gsi_commit_edge_inserts (); |
dd277d48 | 1274 | if (need_ssa_update_p (cfun)) |
095dcfa3 | 1275 | rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); |
9bf0a3f9 | 1276 | |
2c7b2f88 | 1277 | return todo; |
7d23383d | 1278 | } |
1279 | ||
1280 | /* Checks whether the statement defining variable *INDEX can be hoisted | |
1281 | out of the loop passed in DATA. Callback for for_each_index. */ | |
1282 | ||
1283 | static bool | |
1284 | may_move_till (tree ref, tree *index, void *data) | |
1285 | { | |
75a70cf9 | 1286 | struct loop *loop = (struct loop *) data, *max_loop; |
7d23383d | 1287 | |
1288 | /* If REF is an array reference, check also that the step and the lower | |
1289 | bound is invariant in LOOP. */ | |
1290 | if (TREE_CODE (ref) == ARRAY_REF) | |
1291 | { | |
75a70cf9 | 1292 | tree step = TREE_OPERAND (ref, 3); |
1293 | tree lbound = TREE_OPERAND (ref, 2); | |
7d23383d | 1294 | |
75a70cf9 | 1295 | max_loop = outermost_invariant_loop (step, loop); |
7d23383d | 1296 | if (!max_loop) |
1297 | return false; | |
1298 | ||
75a70cf9 | 1299 | max_loop = outermost_invariant_loop (lbound, loop); |
7d23383d | 1300 | if (!max_loop) |
1301 | return false; | |
1302 | } | |
1303 | ||
1304 | max_loop = outermost_invariant_loop (*index, loop); | |
1305 | if (!max_loop) | |
1306 | return false; | |
1307 | ||
1308 | return true; | |
1309 | } | |
1310 | ||
75a70cf9 | 1311 | /* If OP is SSA NAME, force the statement that defines it to be |
99e96094 | 1312 | moved out of the LOOP. ORIG_LOOP is the loop in that EXPR is used. */ |
7d23383d | 1313 | |
1314 | static void | |
75a70cf9 | 1315 | force_move_till_op (tree op, struct loop *orig_loop, struct loop *loop) |
7d23383d | 1316 | { |
42acab1c | 1317 | gimple *stmt; |
7d23383d | 1318 | |
75a70cf9 | 1319 | if (!op |
1320 | || is_gimple_min_invariant (op)) | |
1321 | return; | |
7d23383d | 1322 | |
75a70cf9 | 1323 | gcc_assert (TREE_CODE (op) == SSA_NAME); |
48e1416a | 1324 | |
75a70cf9 | 1325 | stmt = SSA_NAME_DEF_STMT (op); |
1326 | if (gimple_nop_p (stmt)) | |
7d23383d | 1327 | return; |
1328 | ||
75a70cf9 | 1329 | set_level (stmt, orig_loop, loop); |
7d23383d | 1330 | } |
1331 | ||
1332 | /* Forces statement defining invariants in REF (and *INDEX) to be moved out of | |
99e96094 | 1333 | the LOOP. The reference REF is used in the loop ORIG_LOOP. Callback for |
1334 | for_each_index. */ | |
1335 | ||
1336 | struct fmt_data | |
1337 | { | |
1338 | struct loop *loop; | |
1339 | struct loop *orig_loop; | |
1340 | }; | |
7d23383d | 1341 | |
1342 | static bool | |
1343 | force_move_till (tree ref, tree *index, void *data) | |
1344 | { | |
f0d6e81c | 1345 | struct fmt_data *fmt_data = (struct fmt_data *) data; |
7d23383d | 1346 | |
1347 | if (TREE_CODE (ref) == ARRAY_REF) | |
1348 | { | |
75a70cf9 | 1349 | tree step = TREE_OPERAND (ref, 3); |
1350 | tree lbound = TREE_OPERAND (ref, 2); | |
7d23383d | 1351 | |
75a70cf9 | 1352 | force_move_till_op (step, fmt_data->orig_loop, fmt_data->loop); |
1353 | force_move_till_op (lbound, fmt_data->orig_loop, fmt_data->loop); | |
7d23383d | 1354 | } |
1355 | ||
75a70cf9 | 1356 | force_move_till_op (*index, fmt_data->orig_loop, fmt_data->loop); |
7d23383d | 1357 | |
1358 | return true; | |
1359 | } | |
1360 | ||
063a8bce | 1361 | /* A function to free the mem_ref object OBJ. */ |
1362 | ||
1363 | static void | |
1ada9901 | 1364 | memref_free (struct im_mem_ref *mem) |
063a8bce | 1365 | { |
f1f41a6c | 1366 | mem->accesses_in_loop.release (); |
063a8bce | 1367 | } |
1368 | ||
1369 | /* Allocates and returns a memory reference description for MEM whose hash | |
1370 | value is HASH and id is ID. */ | |
1371 | ||
4a7ff262 | 1372 | static im_mem_ref * |
1b94b295 | 1373 | mem_ref_alloc (ao_ref *mem, unsigned hash, unsigned id) |
063a8bce | 1374 | { |
4a7ff262 | 1375 | im_mem_ref *ref = XOBNEW (&mem_ref_obstack, struct im_mem_ref); |
1b94b295 | 1376 | if (mem) |
1377 | ref->mem = *mem; | |
1378 | else | |
1379 | ao_ref_init (&ref->mem, error_mark_node); | |
063a8bce | 1380 | ref->id = id; |
1b94b295 | 1381 | ref->ref_canonical = false; |
063a8bce | 1382 | ref->hash = hash; |
3e48928c | 1383 | ref->stored = NULL; |
feba4360 | 1384 | bitmap_initialize (&ref->indep_loop, &lim_bitmap_obstack); |
1385 | bitmap_initialize (&ref->dep_loop, &lim_bitmap_obstack); | |
3e48928c | 1386 | ref->accesses_in_loop.create (1); |
063a8bce | 1387 | |
1388 | return ref; | |
1389 | } | |
1390 | ||
063a8bce | 1391 | /* Records memory reference location *LOC in LOOP to the memory reference |
1392 | description REF. The reference occurs in statement STMT. */ | |
7d23383d | 1393 | |
1394 | static void | |
42acab1c | 1395 | record_mem_ref_loc (im_mem_ref *ref, gimple *stmt, tree *loc) |
7d23383d | 1396 | { |
5c8a8be3 | 1397 | mem_ref_loc aref; |
5c8a8be3 | 1398 | aref.stmt = stmt; |
1399 | aref.ref = loc; | |
3e48928c | 1400 | ref->accesses_in_loop.safe_push (aref); |
1401 | } | |
1402 | ||
1403 | /* Set the LOOP bit in REF stored bitmap and allocate that if | |
1404 | necessary. Return whether a bit was changed. */ | |
1405 | ||
1406 | static bool | |
4a7ff262 | 1407 | set_ref_stored_in_loop (im_mem_ref *ref, struct loop *loop) |
3e48928c | 1408 | { |
1409 | if (!ref->stored) | |
1410 | ref->stored = BITMAP_ALLOC (&lim_bitmap_obstack); | |
1411 | return bitmap_set_bit (ref->stored, loop->num); | |
7d23383d | 1412 | } |
1413 | ||
063a8bce | 1414 | /* Marks reference REF as stored in LOOP. */ |
7d23383d | 1415 | |
1416 | static void | |
4a7ff262 | 1417 | mark_ref_stored (im_mem_ref *ref, struct loop *loop) |
7d23383d | 1418 | { |
feba4360 | 1419 | while (loop != current_loops->tree_root |
3e48928c | 1420 | && set_ref_stored_in_loop (ref, loop)) |
feba4360 | 1421 | loop = loop_outer (loop); |
063a8bce | 1422 | } |
1423 | ||
1424 | /* Gathers memory references in statement STMT in LOOP, storing the | |
1425 | information about them in the memory_accesses structure. Marks | |
1426 | the vops accessed through unrecognized statements there as | |
1427 | well. */ | |
1428 | ||
1429 | static void | |
42acab1c | 1430 | gather_mem_refs_stmt (struct loop *loop, gimple *stmt) |
063a8bce | 1431 | { |
1432 | tree *mem = NULL; | |
1433 | hashval_t hash; | |
1ada9901 | 1434 | im_mem_ref **slot; |
4a7ff262 | 1435 | im_mem_ref *ref; |
063a8bce | 1436 | bool is_stored; |
063a8bce | 1437 | unsigned id; |
7d23383d | 1438 | |
dd277d48 | 1439 | if (!gimple_vuse (stmt)) |
063a8bce | 1440 | return; |
1441 | ||
1442 | mem = simple_mem_ref_in_stmt (stmt, &is_stored); | |
1443 | if (!mem) | |
0766b2c0 | 1444 | { |
04911505 | 1445 | /* We use the shared mem_ref for all unanalyzable refs. */ |
1446 | id = UNANALYZABLE_MEM_ID; | |
1447 | ref = memory_accesses.refs_list[id]; | |
0766b2c0 | 1448 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1449 | { | |
1450 | fprintf (dump_file, "Unanalyzed memory reference %u: ", id); | |
1451 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1452 | } | |
04911505 | 1453 | is_stored = gimple_vdef (stmt); |
063a8bce | 1454 | } |
1455 | else | |
7d23383d | 1456 | { |
1b94b295 | 1457 | /* We are looking for equal refs that might differ in structure |
1458 | such as a.b vs. MEM[&a + 4]. So we key off the ao_ref but | |
1459 | make sure we can canonicalize the ref in the hashtable if | |
1460 | non-operand_equal_p refs are found. For the lookup we mark | |
1461 | the case we want strict equality with aor.max_size == -1. */ | |
1462 | ao_ref aor; | |
1463 | ao_ref_init (&aor, *mem); | |
1464 | ao_ref_base (&aor); | |
1465 | ao_ref_alias_set (&aor); | |
1466 | HOST_WIDE_INT offset, size, max_size; | |
1467 | poly_int64 saved_maxsize = aor.max_size, mem_off; | |
1468 | tree mem_base; | |
1469 | if (aor.max_size_known_p () | |
1470 | && aor.offset.is_constant (&offset) | |
1471 | && aor.offset.is_constant (&size) | |
1472 | && aor.offset.is_constant (&max_size) | |
1473 | && size == max_size | |
1474 | && (mem_base = get_addr_base_and_unit_offset (aor.ref, &mem_off))) | |
1475 | { | |
1476 | hash = iterative_hash_expr (ao_ref_base (&aor), 0); | |
1477 | hash = iterative_hash_host_wide_int (offset, hash); | |
1478 | hash = iterative_hash_host_wide_int (size, hash); | |
1479 | } | |
1480 | else | |
1481 | { | |
1482 | hash = iterative_hash_expr (aor.ref, 0); | |
1483 | aor.max_size = -1; | |
1484 | } | |
1485 | slot = memory_accesses.refs->find_slot_with_hash (&aor, hash, INSERT); | |
1486 | aor.max_size = saved_maxsize; | |
04911505 | 1487 | if (*slot) |
063a8bce | 1488 | { |
1b94b295 | 1489 | if (!(*slot)->ref_canonical |
1490 | && !operand_equal_p (*mem, (*slot)->mem.ref, 0)) | |
1491 | { | |
1492 | /* If we didn't yet canonicalize the hashtable ref (which | |
1493 | we'll end up using for code insertion) and hit a second | |
1494 | equal ref that is not structurally equivalent create | |
1495 | a canonical ref which is a bare MEM_REF. */ | |
1496 | if (TREE_CODE (*mem) == MEM_REF | |
1497 | || TREE_CODE (*mem) == TARGET_MEM_REF) | |
1498 | { | |
1499 | (*slot)->mem.ref = *mem; | |
1500 | (*slot)->mem.base_alias_set = ao_ref_base_alias_set (&aor); | |
1501 | } | |
1502 | else | |
1503 | { | |
1504 | tree ref_alias_type = reference_alias_ptr_type (*mem); | |
1505 | unsigned int ref_align = get_object_alignment (*mem); | |
1506 | tree ref_type = TREE_TYPE (*mem); | |
1507 | tree tmp = build_fold_addr_expr (unshare_expr (mem_base)); | |
1508 | if (TYPE_ALIGN (ref_type) != ref_align) | |
1509 | ref_type = build_aligned_type (ref_type, ref_align); | |
1510 | (*slot)->mem.ref | |
1511 | = fold_build2 (MEM_REF, ref_type, tmp, | |
1512 | build_int_cst (ref_alias_type, mem_off)); | |
1513 | if ((*slot)->mem.volatile_p) | |
1514 | TREE_THIS_VOLATILE ((*slot)->mem.ref) = 1; | |
1515 | gcc_checking_assert (TREE_CODE ((*slot)->mem.ref) == MEM_REF | |
1516 | && is_gimple_mem_ref_addr | |
1517 | (TREE_OPERAND ((*slot)->mem.ref, | |
1518 | 0))); | |
1519 | (*slot)->mem.base_alias_set = (*slot)->mem.ref_alias_set; | |
1520 | } | |
1521 | (*slot)->ref_canonical = true; | |
1522 | } | |
4a7ff262 | 1523 | ref = *slot; |
04911505 | 1524 | id = ref->id; |
063a8bce | 1525 | } |
04911505 | 1526 | else |
1527 | { | |
1528 | id = memory_accesses.refs_list.length (); | |
1b94b295 | 1529 | ref = mem_ref_alloc (&aor, hash, id); |
04911505 | 1530 | memory_accesses.refs_list.safe_push (ref); |
1531 | *slot = ref; | |
61025ec0 | 1532 | |
04911505 | 1533 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1534 | { | |
1535 | fprintf (dump_file, "Memory reference %u: ", id); | |
1536 | print_generic_expr (dump_file, ref->mem.ref, TDF_SLIM); | |
1537 | fprintf (dump_file, "\n"); | |
1538 | } | |
1539 | } | |
1540 | ||
3e48928c | 1541 | record_mem_ref_loc (ref, stmt, mem); |
04911505 | 1542 | } |
feba4360 | 1543 | bitmap_set_bit (&memory_accesses.refs_in_loop[loop->num], ref->id); |
063a8bce | 1544 | if (is_stored) |
8f9829e8 | 1545 | { |
feba4360 | 1546 | bitmap_set_bit (&memory_accesses.refs_stored_in_loop[loop->num], ref->id); |
8f9829e8 | 1547 | mark_ref_stored (ref, loop); |
1548 | } | |
735d8b51 | 1549 | init_lim_data (stmt)->ref = ref->id; |
063a8bce | 1550 | return; |
7d23383d | 1551 | } |
1552 | ||
7894a3d9 | 1553 | static unsigned *bb_loop_postorder; |
1554 | ||
1555 | /* qsort sort function to sort blocks after their loop fathers postorder. */ | |
1556 | ||
1557 | static int | |
1558 | sort_bbs_in_loop_postorder_cmp (const void *bb1_, const void *bb2_) | |
1559 | { | |
1560 | basic_block bb1 = *(basic_block *)const_cast<void *>(bb1_); | |
1561 | basic_block bb2 = *(basic_block *)const_cast<void *>(bb2_); | |
1562 | struct loop *loop1 = bb1->loop_father; | |
1563 | struct loop *loop2 = bb2->loop_father; | |
1564 | if (loop1->num == loop2->num) | |
2bd42196 | 1565 | return bb1->index - bb2->index; |
7894a3d9 | 1566 | return bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num] ? -1 : 1; |
1567 | } | |
1568 | ||
3e48928c | 1569 | /* qsort sort function to sort ref locs after their loop fathers postorder. */ |
1570 | ||
1571 | static int | |
1572 | sort_locs_in_loop_postorder_cmp (const void *loc1_, const void *loc2_) | |
1573 | { | |
1574 | mem_ref_loc *loc1 = (mem_ref_loc *)const_cast<void *>(loc1_); | |
1575 | mem_ref_loc *loc2 = (mem_ref_loc *)const_cast<void *>(loc2_); | |
1576 | struct loop *loop1 = gimple_bb (loc1->stmt)->loop_father; | |
1577 | struct loop *loop2 = gimple_bb (loc2->stmt)->loop_father; | |
1578 | if (loop1->num == loop2->num) | |
1579 | return 0; | |
1580 | return bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num] ? -1 : 1; | |
1581 | } | |
1582 | ||
063a8bce | 1583 | /* Gathers memory references in loops. */ |
7d23383d | 1584 | |
1585 | static void | |
feba4360 | 1586 | analyze_memory_references (void) |
7d23383d | 1587 | { |
75a70cf9 | 1588 | gimple_stmt_iterator bsi; |
7894a3d9 | 1589 | basic_block bb, *bbs; |
8f9829e8 | 1590 | struct loop *loop, *outer; |
7894a3d9 | 1591 | unsigned i, n; |
063a8bce | 1592 | |
7894a3d9 | 1593 | /* Collect all basic-blocks in loops and sort them after their |
1594 | loops postorder. */ | |
1595 | i = 0; | |
a28770e1 | 1596 | bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS); |
fc00614f | 1597 | FOR_EACH_BB_FN (bb, cfun) |
7894a3d9 | 1598 | if (bb->loop_father != current_loops->tree_root) |
1599 | bbs[i++] = bb; | |
1600 | n = i; | |
1601 | qsort (bbs, n, sizeof (basic_block), sort_bbs_in_loop_postorder_cmp); | |
7894a3d9 | 1602 | |
1603 | /* Visit blocks in loop postorder and assign mem-ref IDs in that order. | |
1604 | That results in better locality for all the bitmaps. */ | |
1605 | for (i = 0; i < n; ++i) | |
063a8bce | 1606 | { |
7894a3d9 | 1607 | basic_block bb = bbs[i]; |
75a70cf9 | 1608 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
7894a3d9 | 1609 | gather_mem_refs_stmt (bb->loop_father, gsi_stmt (bsi)); |
063a8bce | 1610 | } |
1611 | ||
3e48928c | 1612 | /* Sort the location list of gathered memory references after their |
1613 | loop postorder number. */ | |
1ada9901 | 1614 | im_mem_ref *ref; |
3e48928c | 1615 | FOR_EACH_VEC_ELT (memory_accesses.refs_list, i, ref) |
1616 | ref->accesses_in_loop.qsort (sort_locs_in_loop_postorder_cmp); | |
1617 | ||
7894a3d9 | 1618 | free (bbs); |
3e48928c | 1619 | // free (bb_loop_postorder); |
7894a3d9 | 1620 | |
0766b2c0 | 1621 | /* Propagate the information about accessed memory references up |
1622 | the loop hierarchy. */ | |
f21d4d00 | 1623 | FOR_EACH_LOOP (loop, LI_FROM_INNERMOST) |
063a8bce | 1624 | { |
8f9829e8 | 1625 | /* Finalize the overall touched references (including subloops). */ |
feba4360 | 1626 | bitmap_ior_into (&memory_accesses.all_refs_stored_in_loop[loop->num], |
1627 | &memory_accesses.refs_stored_in_loop[loop->num]); | |
8f9829e8 | 1628 | |
1629 | /* Propagate the information about accessed memory references up | |
1630 | the loop hierarchy. */ | |
1631 | outer = loop_outer (loop); | |
1632 | if (outer == current_loops->tree_root) | |
063a8bce | 1633 | continue; |
1634 | ||
feba4360 | 1635 | bitmap_ior_into (&memory_accesses.all_refs_stored_in_loop[outer->num], |
1636 | &memory_accesses.all_refs_stored_in_loop[loop->num]); | |
063a8bce | 1637 | } |
063a8bce | 1638 | } |
1639 | ||
063a8bce | 1640 | /* Returns true if MEM1 and MEM2 may alias. TTAE_CACHE is used as a cache in |
1641 | tree_to_aff_combination_expand. */ | |
1642 | ||
1643 | static bool | |
4a7ff262 | 1644 | mem_refs_may_alias_p (im_mem_ref *mem1, im_mem_ref *mem2, |
5f8841a5 | 1645 | hash_map<tree, name_expansion *> **ttae_cache) |
063a8bce | 1646 | { |
1647 | /* Perform BASE + OFFSET analysis -- if MEM1 and MEM2 are based on the same | |
1648 | object and their offset differ in such a way that the locations cannot | |
1649 | overlap, then they cannot alias. */ | |
fbc666b8 | 1650 | poly_widest_int size1, size2; |
3391cd1e | 1651 | aff_tree off1, off2; |
063a8bce | 1652 | |
3391cd1e | 1653 | /* Perform basic offset and type-based disambiguation. */ |
09f4cf62 | 1654 | if (!refs_may_alias_p_1 (&mem1->mem, &mem2->mem, true)) |
063a8bce | 1655 | return false; |
7d23383d | 1656 | |
063a8bce | 1657 | /* The expansion of addresses may be a bit expensive, thus we only do |
1658 | the check at -O2 and higher optimization levels. */ | |
1659 | if (optimize < 2) | |
1660 | return true; | |
1661 | ||
09f4cf62 | 1662 | get_inner_reference_aff (mem1->mem.ref, &off1, &size1); |
1663 | get_inner_reference_aff (mem2->mem.ref, &off2, &size2); | |
063a8bce | 1664 | aff_combination_expand (&off1, ttae_cache); |
1665 | aff_combination_expand (&off2, ttae_cache); | |
e913b5cd | 1666 | aff_combination_scale (&off1, -1); |
063a8bce | 1667 | aff_combination_add (&off2, &off1); |
1668 | ||
5fc88ffd | 1669 | if (aff_comb_cannot_overlap_p (&off2, size1, size2)) |
063a8bce | 1670 | return false; |
1671 | ||
1672 | return true; | |
1673 | } | |
1674 | ||
3e48928c | 1675 | /* Compare function for bsearch searching for reference locations |
1676 | in a loop. */ | |
1677 | ||
1678 | static int | |
1679 | find_ref_loc_in_loop_cmp (const void *loop_, const void *loc_) | |
1680 | { | |
1681 | struct loop *loop = (struct loop *)const_cast<void *>(loop_); | |
1682 | mem_ref_loc *loc = (mem_ref_loc *)const_cast<void *>(loc_); | |
1683 | struct loop *loc_loop = gimple_bb (loc->stmt)->loop_father; | |
1684 | if (loop->num == loc_loop->num | |
1685 | || flow_loop_nested_p (loop, loc_loop)) | |
1686 | return 0; | |
1687 | return (bb_loop_postorder[loop->num] < bb_loop_postorder[loc_loop->num] | |
1688 | ? -1 : 1); | |
1689 | } | |
1690 | ||
5c8a8be3 | 1691 | /* Iterates over all locations of REF in LOOP and its subloops calling |
1692 | fn.operator() with the location as argument. When that operator | |
1693 | returns true the iteration is stopped and true is returned. | |
1694 | Otherwise false is returned. */ | |
063a8bce | 1695 | |
5c8a8be3 | 1696 | template <typename FN> |
1697 | static bool | |
4a7ff262 | 1698 | for_all_locs_in_loop (struct loop *loop, im_mem_ref *ref, FN fn) |
063a8bce | 1699 | { |
063a8bce | 1700 | unsigned i; |
4a7ff262 | 1701 | mem_ref_loc *loc; |
063a8bce | 1702 | |
3e48928c | 1703 | /* Search for the cluster of locs in the accesses_in_loop vector |
1704 | which is sorted after postorder index of the loop father. */ | |
1705 | loc = ref->accesses_in_loop.bsearch (loop, find_ref_loc_in_loop_cmp); | |
1706 | if (!loc) | |
1707 | return false; | |
063a8bce | 1708 | |
3e48928c | 1709 | /* We have found one location inside loop or its sub-loops. Iterate |
1710 | both forward and backward to cover the whole cluster. */ | |
1711 | i = loc - ref->accesses_in_loop.address (); | |
1712 | while (i > 0) | |
1713 | { | |
1714 | --i; | |
4a7ff262 | 1715 | mem_ref_loc *l = &ref->accesses_in_loop[i]; |
3e48928c | 1716 | if (!flow_bb_inside_loop_p (loop, gimple_bb (l->stmt))) |
1717 | break; | |
1718 | if (fn (l)) | |
1719 | return true; | |
1720 | } | |
1721 | for (i = loc - ref->accesses_in_loop.address (); | |
1722 | i < ref->accesses_in_loop.length (); ++i) | |
1723 | { | |
4a7ff262 | 1724 | mem_ref_loc *l = &ref->accesses_in_loop[i]; |
3e48928c | 1725 | if (!flow_bb_inside_loop_p (loop, gimple_bb (l->stmt))) |
1726 | break; | |
1727 | if (fn (l)) | |
1728 | return true; | |
1729 | } | |
5c8a8be3 | 1730 | |
1731 | return false; | |
1732 | } | |
1733 | ||
1734 | /* Rewrites location LOC by TMP_VAR. */ | |
1735 | ||
1736 | struct rewrite_mem_ref_loc | |
1737 | { | |
1738 | rewrite_mem_ref_loc (tree tmp_var_) : tmp_var (tmp_var_) {} | |
4a7ff262 | 1739 | bool operator () (mem_ref_loc *loc); |
5c8a8be3 | 1740 | tree tmp_var; |
1741 | }; | |
1742 | ||
1743 | bool | |
4a7ff262 | 1744 | rewrite_mem_ref_loc::operator () (mem_ref_loc *loc) |
5c8a8be3 | 1745 | { |
1746 | *loc->ref = tmp_var; | |
1747 | update_stmt (loc->stmt); | |
1748 | return false; | |
063a8bce | 1749 | } |
1750 | ||
1751 | /* Rewrites all references to REF in LOOP by variable TMP_VAR. */ | |
1752 | ||
1753 | static void | |
4a7ff262 | 1754 | rewrite_mem_refs (struct loop *loop, im_mem_ref *ref, tree tmp_var) |
063a8bce | 1755 | { |
5c8a8be3 | 1756 | for_all_locs_in_loop (loop, ref, rewrite_mem_ref_loc (tmp_var)); |
7d23383d | 1757 | } |
1758 | ||
bc9af2dd | 1759 | /* Stores the first reference location in LOCP. */ |
1760 | ||
1761 | struct first_mem_ref_loc_1 | |
1762 | { | |
4a7ff262 | 1763 | first_mem_ref_loc_1 (mem_ref_loc **locp_) : locp (locp_) {} |
1764 | bool operator () (mem_ref_loc *loc); | |
1765 | mem_ref_loc **locp; | |
bc9af2dd | 1766 | }; |
1767 | ||
1768 | bool | |
4a7ff262 | 1769 | first_mem_ref_loc_1::operator () (mem_ref_loc *loc) |
bc9af2dd | 1770 | { |
1771 | *locp = loc; | |
1772 | return true; | |
1773 | } | |
1774 | ||
1775 | /* Returns the first reference location to REF in LOOP. */ | |
1776 | ||
4a7ff262 | 1777 | static mem_ref_loc * |
1778 | first_mem_ref_loc (struct loop *loop, im_mem_ref *ref) | |
bc9af2dd | 1779 | { |
4a7ff262 | 1780 | mem_ref_loc *locp = NULL; |
bc9af2dd | 1781 | for_all_locs_in_loop (loop, ref, first_mem_ref_loc_1 (&locp)); |
1782 | return locp; | |
1783 | } | |
1784 | ||
61025ec0 | 1785 | struct prev_flag_edges { |
1786 | /* Edge to insert new flag comparison code. */ | |
1787 | edge append_cond_position; | |
1788 | ||
1789 | /* Edge for fall through from previous flag comparison. */ | |
1790 | edge last_cond_fallthru; | |
1791 | }; | |
1792 | ||
1793 | /* Helper function for execute_sm. Emit code to store TMP_VAR into | |
1794 | MEM along edge EX. | |
1795 | ||
1796 | The store is only done if MEM has changed. We do this so no | |
1797 | changes to MEM occur on code paths that did not originally store | |
1798 | into it. | |
1799 | ||
1800 | The common case for execute_sm will transform: | |
1801 | ||
1802 | for (...) { | |
1803 | if (foo) | |
1804 | stuff; | |
1805 | else | |
1806 | MEM = TMP_VAR; | |
1807 | } | |
1808 | ||
1809 | into: | |
1810 | ||
1811 | lsm = MEM; | |
1812 | for (...) { | |
1813 | if (foo) | |
1814 | stuff; | |
1815 | else | |
1816 | lsm = TMP_VAR; | |
1817 | } | |
1818 | MEM = lsm; | |
1819 | ||
1820 | This function will generate: | |
1821 | ||
1822 | lsm = MEM; | |
1823 | ||
1824 | lsm_flag = false; | |
1825 | ... | |
1826 | for (...) { | |
1827 | if (foo) | |
1828 | stuff; | |
1829 | else { | |
1830 | lsm = TMP_VAR; | |
1831 | lsm_flag = true; | |
1832 | } | |
1833 | } | |
1834 | if (lsm_flag) <-- | |
1835 | MEM = lsm; <-- | |
1836 | */ | |
1837 | ||
1838 | static void | |
1ea7c812 | 1839 | execute_sm_if_changed (edge ex, tree mem, tree tmp_var, tree flag, |
1840 | edge preheader, hash_set <basic_block> *flag_bbs) | |
61025ec0 | 1841 | { |
1842 | basic_block new_bb, then_bb, old_dest; | |
1843 | bool loop_has_only_one_exit; | |
1844 | edge then_old_edge, orig_ex = ex; | |
1845 | gimple_stmt_iterator gsi; | |
42acab1c | 1846 | gimple *stmt; |
61025ec0 | 1847 | struct prev_flag_edges *prev_edges = (struct prev_flag_edges *) ex->aux; |
a1ccf30d | 1848 | bool irr = ex->flags & EDGE_IRREDUCIBLE_LOOP; |
61025ec0 | 1849 | |
1ea7c812 | 1850 | profile_count count_sum = profile_count::zero (); |
1851 | int nbbs = 0, ncount = 0; | |
720cfc43 | 1852 | profile_probability flag_probability = profile_probability::uninitialized (); |
1ea7c812 | 1853 | |
1854 | /* Flag is set in FLAG_BBS. Determine probability that flag will be true | |
1855 | at loop exit. | |
1856 | ||
1857 | This code may look fancy, but it can not update profile very realistically | |
1858 | because we do not know the probability that flag will be true at given | |
1859 | loop exit. | |
1860 | ||
1861 | We look for two interesting extremes | |
1862 | - when exit is dominated by block setting the flag, we know it will | |
1863 | always be true. This is a common case. | |
1864 | - when all blocks setting the flag have very low frequency we know | |
1865 | it will likely be false. | |
1866 | In all other cases we default to 2/3 for flag being true. */ | |
1867 | ||
1868 | for (hash_set<basic_block>::iterator it = flag_bbs->begin (); | |
1869 | it != flag_bbs->end (); ++it) | |
1870 | { | |
1ea7c812 | 1871 | if ((*it)->count.initialized_p ()) |
1872 | count_sum += (*it)->count, ncount ++; | |
1873 | if (dominated_by_p (CDI_DOMINATORS, ex->src, *it)) | |
720cfc43 | 1874 | flag_probability = profile_probability::always (); |
1ea7c812 | 1875 | nbbs++; |
1876 | } | |
1877 | ||
720cfc43 | 1878 | profile_probability cap = profile_probability::always ().apply_scale (2, 3); |
1879 | ||
1880 | if (flag_probability.initialized_p ()) | |
1ea7c812 | 1881 | ; |
205ce1aa | 1882 | else if (ncount == nbbs |
1883 | && preheader->count () >= count_sum && preheader->count ().nonzero_p ()) | |
1ea7c812 | 1884 | { |
ea5d3981 | 1885 | flag_probability = count_sum.probability_in (preheader->count ()); |
720cfc43 | 1886 | if (flag_probability > cap) |
1887 | flag_probability = cap; | |
1ea7c812 | 1888 | } |
205ce1aa | 1889 | |
1890 | if (!flag_probability.initialized_p ()) | |
720cfc43 | 1891 | flag_probability = cap; |
1ea7c812 | 1892 | |
61025ec0 | 1893 | /* ?? Insert store after previous store if applicable. See note |
1894 | below. */ | |
1895 | if (prev_edges) | |
1896 | ex = prev_edges->append_cond_position; | |
1897 | ||
1898 | loop_has_only_one_exit = single_pred_p (ex->dest); | |
1899 | ||
1900 | if (loop_has_only_one_exit) | |
1901 | ex = split_block_after_labels (ex->dest); | |
a1ebf6df | 1902 | else |
1903 | { | |
1904 | for (gphi_iterator gpi = gsi_start_phis (ex->dest); | |
1905 | !gsi_end_p (gpi); gsi_next (&gpi)) | |
1906 | { | |
1907 | gphi *phi = gpi.phi (); | |
1908 | if (virtual_operand_p (gimple_phi_result (phi))) | |
1909 | continue; | |
1910 | ||
1911 | /* When the destination has a non-virtual PHI node with multiple | |
1912 | predecessors make sure we preserve the PHI structure by | |
1913 | forcing a forwarder block so that hoisting of that PHI will | |
1914 | still work. */ | |
1915 | split_edge (ex); | |
1916 | break; | |
1917 | } | |
1918 | } | |
61025ec0 | 1919 | |
1920 | old_dest = ex->dest; | |
1921 | new_bb = split_edge (ex); | |
1922 | then_bb = create_empty_bb (new_bb); | |
1ea7c812 | 1923 | then_bb->count = new_bb->count.apply_probability (flag_probability); |
a1ccf30d | 1924 | if (irr) |
1925 | then_bb->flags = BB_IRREDUCIBLE_LOOP; | |
1926 | add_bb_to_loop (then_bb, new_bb->loop_father); | |
61025ec0 | 1927 | |
1928 | gsi = gsi_start_bb (new_bb); | |
1929 | stmt = gimple_build_cond (NE_EXPR, flag, boolean_false_node, | |
1930 | NULL_TREE, NULL_TREE); | |
1931 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1932 | ||
1933 | gsi = gsi_start_bb (then_bb); | |
1934 | /* Insert actual store. */ | |
1935 | stmt = gimple_build_assign (unshare_expr (mem), tmp_var); | |
1936 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1937 | ||
1ea7c812 | 1938 | edge e1 = single_succ_edge (new_bb); |
1939 | edge e2 = make_edge (new_bb, then_bb, | |
1940 | EDGE_TRUE_VALUE | (irr ? EDGE_IRREDUCIBLE_LOOP : 0)); | |
1941 | e2->probability = flag_probability; | |
1ea7c812 | 1942 | |
1943 | e1->flags |= EDGE_FALSE_VALUE | (irr ? EDGE_IRREDUCIBLE_LOOP : 0); | |
1944 | e1->flags &= ~EDGE_FALLTHRU; | |
1945 | ||
720cfc43 | 1946 | e1->probability = flag_probability.invert (); |
1ea7c812 | 1947 | |
720cfc43 | 1948 | then_old_edge = make_single_succ_edge (then_bb, old_dest, |
a1ccf30d | 1949 | EDGE_FALLTHRU | (irr ? EDGE_IRREDUCIBLE_LOOP : 0)); |
61025ec0 | 1950 | |
1951 | set_immediate_dominator (CDI_DOMINATORS, then_bb, new_bb); | |
1952 | ||
1953 | if (prev_edges) | |
1954 | { | |
1955 | basic_block prevbb = prev_edges->last_cond_fallthru->src; | |
1956 | redirect_edge_succ (prev_edges->last_cond_fallthru, new_bb); | |
1957 | set_immediate_dominator (CDI_DOMINATORS, new_bb, prevbb); | |
1958 | set_immediate_dominator (CDI_DOMINATORS, old_dest, | |
1959 | recompute_dominator (CDI_DOMINATORS, old_dest)); | |
1960 | } | |
1961 | ||
1962 | /* ?? Because stores may alias, they must happen in the exact | |
1963 | sequence they originally happened. Save the position right after | |
1964 | the (_lsm) store we just created so we can continue appending after | |
1965 | it and maintain the original order. */ | |
1966 | { | |
1967 | struct prev_flag_edges *p; | |
1968 | ||
1969 | if (orig_ex->aux) | |
1970 | orig_ex->aux = NULL; | |
1971 | alloc_aux_for_edge (orig_ex, sizeof (struct prev_flag_edges)); | |
1972 | p = (struct prev_flag_edges *) orig_ex->aux; | |
1973 | p->append_cond_position = then_old_edge; | |
1974 | p->last_cond_fallthru = find_edge (new_bb, old_dest); | |
1975 | orig_ex->aux = (void *) p; | |
1976 | } | |
1977 | ||
1978 | if (!loop_has_only_one_exit) | |
1a91d914 | 1979 | for (gphi_iterator gpi = gsi_start_phis (old_dest); |
1980 | !gsi_end_p (gpi); gsi_next (&gpi)) | |
61025ec0 | 1981 | { |
1a91d914 | 1982 | gphi *phi = gpi.phi (); |
61025ec0 | 1983 | unsigned i; |
1984 | ||
1985 | for (i = 0; i < gimple_phi_num_args (phi); i++) | |
1986 | if (gimple_phi_arg_edge (phi, i)->src == new_bb) | |
1987 | { | |
1988 | tree arg = gimple_phi_arg_def (phi, i); | |
60d535d2 | 1989 | add_phi_arg (phi, arg, then_old_edge, UNKNOWN_LOCATION); |
61025ec0 | 1990 | update_stmt (phi); |
1991 | } | |
1992 | } | |
61025ec0 | 1993 | } |
1994 | ||
5c8a8be3 | 1995 | /* When REF is set on the location, set flag indicating the store. */ |
1996 | ||
1997 | struct sm_set_flag_if_changed | |
1998 | { | |
1ea7c812 | 1999 | sm_set_flag_if_changed (tree flag_, hash_set <basic_block> *bbs_) |
2000 | : flag (flag_), bbs (bbs_) {} | |
4a7ff262 | 2001 | bool operator () (mem_ref_loc *loc); |
5c8a8be3 | 2002 | tree flag; |
1ea7c812 | 2003 | hash_set <basic_block> *bbs; |
5c8a8be3 | 2004 | }; |
2005 | ||
2006 | bool | |
4a7ff262 | 2007 | sm_set_flag_if_changed::operator () (mem_ref_loc *loc) |
5c8a8be3 | 2008 | { |
2009 | /* Only set the flag for writes. */ | |
2010 | if (is_gimple_assign (loc->stmt) | |
2011 | && gimple_assign_lhs_ptr (loc->stmt) == loc->ref) | |
2012 | { | |
2013 | gimple_stmt_iterator gsi = gsi_for_stmt (loc->stmt); | |
42acab1c | 2014 | gimple *stmt = gimple_build_assign (flag, boolean_true_node); |
5c8a8be3 | 2015 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); |
1ea7c812 | 2016 | bbs->add (gimple_bb (stmt)); |
5c8a8be3 | 2017 | } |
2018 | return false; | |
2019 | } | |
2020 | ||
61025ec0 | 2021 | /* Helper function for execute_sm. On every location where REF is |
2022 | set, set an appropriate flag indicating the store. */ | |
2023 | ||
2024 | static tree | |
1ea7c812 | 2025 | execute_sm_if_changed_flag_set (struct loop *loop, im_mem_ref *ref, |
2026 | hash_set <basic_block> *bbs) | |
61025ec0 | 2027 | { |
61025ec0 | 2028 | tree flag; |
f86b328b | 2029 | char *str = get_lsm_tmp_name (ref->mem.ref, ~0, "_flag"); |
072f7ab1 | 2030 | flag = create_tmp_reg (boolean_type_node, str); |
1ea7c812 | 2031 | for_all_locs_in_loop (loop, ref, sm_set_flag_if_changed (flag, bbs)); |
61025ec0 | 2032 | return flag; |
2033 | } | |
2034 | ||
063a8bce | 2035 | /* Executes store motion of memory reference REF from LOOP. |
749ea85f | 2036 | Exits from the LOOP are stored in EXITS. The initialization of the |
2037 | temporary variable is put to the preheader of the loop, and assignments | |
2038 | to the reference from the temporary variable are emitted to exits. */ | |
7d23383d | 2039 | |
2040 | static void | |
4a7ff262 | 2041 | execute_sm (struct loop *loop, vec<edge> exits, im_mem_ref *ref) |
7d23383d | 2042 | { |
3e48928c | 2043 | tree tmp_var, store_flag = NULL_TREE; |
7d23383d | 2044 | unsigned i; |
1a91d914 | 2045 | gassign *load; |
99e96094 | 2046 | struct fmt_data fmt_data; |
bc9af2dd | 2047 | edge ex; |
75a70cf9 | 2048 | struct lim_aux_data *lim_data; |
61025ec0 | 2049 | bool multi_threaded_model_p = false; |
bc9af2dd | 2050 | gimple_stmt_iterator gsi; |
1ea7c812 | 2051 | hash_set<basic_block> flag_bbs; |
7d23383d | 2052 | |
69154f26 | 2053 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2054 | { | |
2055 | fprintf (dump_file, "Executing store motion of "); | |
1ffa4346 | 2056 | print_generic_expr (dump_file, ref->mem.ref); |
69154f26 | 2057 | fprintf (dump_file, " from loop %d\n", loop->num); |
2058 | } | |
2059 | ||
09f4cf62 | 2060 | tmp_var = create_tmp_reg (TREE_TYPE (ref->mem.ref), |
2061 | get_lsm_tmp_name (ref->mem.ref, ~0)); | |
7d23383d | 2062 | |
99e96094 | 2063 | fmt_data.loop = loop; |
2064 | fmt_data.orig_loop = loop; | |
09f4cf62 | 2065 | for_each_index (&ref->mem.ref, force_move_till, &fmt_data); |
7d23383d | 2066 | |
c927329e | 2067 | if (bb_in_transaction (loop_preheader_edge (loop)->src) |
60b209bc | 2068 | || (! PARAM_VALUE (PARAM_ALLOW_STORE_DATA_RACES) |
2069 | && ! ref_always_accessed_p (loop, ref, true))) | |
61025ec0 | 2070 | multi_threaded_model_p = true; |
2071 | ||
2072 | if (multi_threaded_model_p) | |
1ea7c812 | 2073 | store_flag = execute_sm_if_changed_flag_set (loop, ref, &flag_bbs); |
61025ec0 | 2074 | |
063a8bce | 2075 | rewrite_mem_refs (loop, ref, tmp_var); |
7d23383d | 2076 | |
bc9af2dd | 2077 | /* Emit the load code on a random exit edge or into the latch if |
2078 | the loop does not exit, so that we are sure it will be processed | |
2079 | by move_computations after all dependencies. */ | |
2080 | gsi = gsi_for_stmt (first_mem_ref_loc (loop, ref)->stmt); | |
61025ec0 | 2081 | |
2082 | /* FIXME/TODO: For the multi-threaded variant, we could avoid this | |
2083 | load altogether, since the store is predicated by a flag. We | |
2084 | could, do the load only if it was originally in the loop. */ | |
09f4cf62 | 2085 | load = gimple_build_assign (tmp_var, unshare_expr (ref->mem.ref)); |
75a70cf9 | 2086 | lim_data = init_lim_data (load); |
2087 | lim_data->max_loop = loop; | |
2088 | lim_data->tgt_loop = loop; | |
bc9af2dd | 2089 | gsi_insert_before (&gsi, load, GSI_SAME_STMT); |
7d23383d | 2090 | |
61025ec0 | 2091 | if (multi_threaded_model_p) |
7d23383d | 2092 | { |
61025ec0 | 2093 | load = gimple_build_assign (store_flag, boolean_false_node); |
2094 | lim_data = init_lim_data (load); | |
2095 | lim_data->max_loop = loop; | |
2096 | lim_data->tgt_loop = loop; | |
bc9af2dd | 2097 | gsi_insert_before (&gsi, load, GSI_SAME_STMT); |
7d23383d | 2098 | } |
61025ec0 | 2099 | |
2100 | /* Sink the store to every exit from the loop. */ | |
f1f41a6c | 2101 | FOR_EACH_VEC_ELT (exits, i, ex) |
61025ec0 | 2102 | if (!multi_threaded_model_p) |
2103 | { | |
1a91d914 | 2104 | gassign *store; |
09f4cf62 | 2105 | store = gimple_build_assign (unshare_expr (ref->mem.ref), tmp_var); |
61025ec0 | 2106 | gsi_insert_on_edge (ex, store); |
2107 | } | |
2108 | else | |
1ea7c812 | 2109 | execute_sm_if_changed (ex, ref->mem.ref, tmp_var, store_flag, |
2110 | loop_preheader_edge (loop), &flag_bbs); | |
7d23383d | 2111 | } |
2112 | ||
063a8bce | 2113 | /* Hoists memory references MEM_REFS out of LOOP. EXITS is the list of exit |
2114 | edges of the LOOP. */ | |
7d23383d | 2115 | |
2116 | static void | |
063a8bce | 2117 | hoist_memory_references (struct loop *loop, bitmap mem_refs, |
f1f41a6c | 2118 | vec<edge> exits) |
7d23383d | 2119 | { |
4a7ff262 | 2120 | im_mem_ref *ref; |
063a8bce | 2121 | unsigned i; |
2122 | bitmap_iterator bi; | |
69154f26 | 2123 | |
063a8bce | 2124 | EXECUTE_IF_SET_IN_BITMAP (mem_refs, 0, i, bi) |
7d23383d | 2125 | { |
f1f41a6c | 2126 | ref = memory_accesses.refs_list[i]; |
063a8bce | 2127 | execute_sm (loop, exits, ref); |
7d23383d | 2128 | } |
55a03692 | 2129 | } |
2130 | ||
5c8a8be3 | 2131 | struct ref_always_accessed |
2132 | { | |
3e48928c | 2133 | ref_always_accessed (struct loop *loop_, bool stored_p_) |
2134 | : loop (loop_), stored_p (stored_p_) {} | |
4a7ff262 | 2135 | bool operator () (mem_ref_loc *loc); |
5c8a8be3 | 2136 | struct loop *loop; |
5c8a8be3 | 2137 | bool stored_p; |
2138 | }; | |
7d23383d | 2139 | |
5c8a8be3 | 2140 | bool |
4a7ff262 | 2141 | ref_always_accessed::operator () (mem_ref_loc *loc) |
7d23383d | 2142 | { |
063a8bce | 2143 | struct loop *must_exec; |
307f7fda | 2144 | |
5c8a8be3 | 2145 | if (!get_lim_data (loc->stmt)) |
2146 | return false; | |
7d23383d | 2147 | |
5c8a8be3 | 2148 | /* If we require an always executed store make sure the statement |
2149 | stores to the reference. */ | |
2150 | if (stored_p) | |
063a8bce | 2151 | { |
3e48928c | 2152 | tree lhs = gimple_get_lhs (loc->stmt); |
2153 | if (!lhs | |
2154 | || lhs != *loc->ref) | |
5c8a8be3 | 2155 | return false; |
2156 | } | |
7d23383d | 2157 | |
5c8a8be3 | 2158 | must_exec = get_lim_data (loc->stmt)->always_executed_in; |
2159 | if (!must_exec) | |
2160 | return false; | |
307f7fda | 2161 | |
5c8a8be3 | 2162 | if (must_exec == loop |
2163 | || flow_loop_nested_p (must_exec, loop)) | |
2164 | return true; | |
7d23383d | 2165 | |
5c8a8be3 | 2166 | return false; |
2167 | } | |
55a03692 | 2168 | |
5c8a8be3 | 2169 | /* Returns true if REF is always accessed in LOOP. If STORED_P is true |
2170 | make sure REF is always stored to in LOOP. */ | |
2171 | ||
2172 | static bool | |
4a7ff262 | 2173 | ref_always_accessed_p (struct loop *loop, im_mem_ref *ref, bool stored_p) |
5c8a8be3 | 2174 | { |
5c8a8be3 | 2175 | return for_all_locs_in_loop (loop, ref, |
3e48928c | 2176 | ref_always_accessed (loop, stored_p)); |
55a03692 | 2177 | } |
2178 | ||
063a8bce | 2179 | /* Returns true if REF1 and REF2 are independent. */ |
55a03692 | 2180 | |
063a8bce | 2181 | static bool |
4a7ff262 | 2182 | refs_independent_p (im_mem_ref *ref1, im_mem_ref *ref2) |
55a03692 | 2183 | { |
09f4cf62 | 2184 | if (ref1 == ref2) |
063a8bce | 2185 | return true; |
09f4cf62 | 2186 | |
063a8bce | 2187 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2188 | fprintf (dump_file, "Querying dependency of refs %u and %u: ", | |
2189 | ref1->id, ref2->id); | |
2190 | ||
09f4cf62 | 2191 | if (mem_refs_may_alias_p (ref1, ref2, &memory_accesses.ttae_cache)) |
063a8bce | 2192 | { |
063a8bce | 2193 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2194 | fprintf (dump_file, "dependent.\n"); | |
2195 | return false; | |
2196 | } | |
2197 | else | |
2198 | { | |
063a8bce | 2199 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2200 | fprintf (dump_file, "independent.\n"); | |
2201 | return true; | |
2202 | } | |
55a03692 | 2203 | } |
2204 | ||
8f9829e8 | 2205 | /* Mark REF dependent on stores or loads (according to STORED_P) in LOOP |
2206 | and its super-loops. */ | |
55a03692 | 2207 | |
2208 | static void | |
4a7ff262 | 2209 | record_dep_loop (struct loop *loop, im_mem_ref *ref, bool stored_p) |
55a03692 | 2210 | { |
8f9829e8 | 2211 | /* We can propagate dependent-in-loop bits up the loop |
2212 | hierarchy to all outer loops. */ | |
2213 | while (loop != current_loops->tree_root | |
feba4360 | 2214 | && bitmap_set_bit (&ref->dep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
8f9829e8 | 2215 | loop = loop_outer (loop); |
063a8bce | 2216 | } |
55a03692 | 2217 | |
3326faef | 2218 | /* Returns true if REF is independent on all other memory |
23298f15 | 2219 | references in LOOP. */ |
55a03692 | 2220 | |
063a8bce | 2221 | static bool |
23298f15 | 2222 | ref_indep_loop_p_1 (struct loop *loop, im_mem_ref *ref, bool stored_p) |
063a8bce | 2223 | { |
3326faef | 2224 | stored_p |= (ref->stored && bitmap_bit_p (ref->stored, loop->num)); |
2225 | ||
3326faef | 2226 | bool indep_p = true; |
0766b2c0 | 2227 | bitmap refs_to_check; |
063a8bce | 2228 | |
8f9829e8 | 2229 | if (stored_p) |
feba4360 | 2230 | refs_to_check = &memory_accesses.refs_in_loop[loop->num]; |
0766b2c0 | 2231 | else |
feba4360 | 2232 | refs_to_check = &memory_accesses.refs_stored_in_loop[loop->num]; |
55a03692 | 2233 | |
04911505 | 2234 | if (bitmap_bit_p (refs_to_check, UNANALYZABLE_MEM_ID)) |
3326faef | 2235 | indep_p = false; |
3326faef | 2236 | else |
55a03692 | 2237 | { |
3326faef | 2238 | if (bitmap_bit_p (&ref->indep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
2239 | return true; | |
2240 | if (bitmap_bit_p (&ref->dep_loop, LOOP_DEP_BIT (loop->num, stored_p))) | |
8f9829e8 | 2241 | return false; |
55a03692 | 2242 | |
3326faef | 2243 | struct loop *inner = loop->inner; |
2244 | while (inner) | |
2245 | { | |
23298f15 | 2246 | if (!ref_indep_loop_p_1 (inner, ref, stored_p)) |
3326faef | 2247 | { |
2248 | indep_p = false; | |
2249 | break; | |
2250 | } | |
2251 | inner = inner->next; | |
2252 | } | |
f339cf78 | 2253 | |
3326faef | 2254 | if (indep_p) |
2255 | { | |
2256 | unsigned i; | |
2257 | bitmap_iterator bi; | |
2258 | EXECUTE_IF_SET_IN_BITMAP (refs_to_check, 0, i, bi) | |
2259 | { | |
2260 | im_mem_ref *aref = memory_accesses.refs_list[i]; | |
2261 | if (!refs_independent_p (ref, aref)) | |
2262 | { | |
2263 | indep_p = false; | |
2264 | break; | |
2265 | } | |
2266 | } | |
2267 | } | |
8f9829e8 | 2268 | } |
2269 | ||
063a8bce | 2270 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2271 | fprintf (dump_file, "Querying dependencies of ref %u in loop %d: %s\n", | |
8f9829e8 | 2272 | ref->id, loop->num, indep_p ? "independent" : "dependent"); |
063a8bce | 2273 | |
8f9829e8 | 2274 | /* Record the computed result in the cache. */ |
2275 | if (indep_p) | |
2276 | { | |
feba4360 | 2277 | if (bitmap_set_bit (&ref->indep_loop, LOOP_DEP_BIT (loop->num, stored_p)) |
8f9829e8 | 2278 | && stored_p) |
2279 | { | |
2280 | /* If it's independend against all refs then it's independent | |
2281 | against stores, too. */ | |
feba4360 | 2282 | bitmap_set_bit (&ref->indep_loop, LOOP_DEP_BIT (loop->num, false)); |
8f9829e8 | 2283 | } |
2284 | } | |
2285 | else | |
2286 | { | |
2287 | record_dep_loop (loop, ref, stored_p); | |
2288 | if (!stored_p) | |
2289 | { | |
2290 | /* If it's dependent against stores it's dependent against | |
2291 | all refs, too. */ | |
2292 | record_dep_loop (loop, ref, true); | |
2293 | } | |
2294 | } | |
063a8bce | 2295 | |
8f9829e8 | 2296 | return indep_p; |
2297 | } | |
2298 | ||
2299 | /* Returns true if REF is independent on all other memory references in | |
23298f15 | 2300 | LOOP. */ |
8f9829e8 | 2301 | |
2302 | static bool | |
23298f15 | 2303 | ref_indep_loop_p (struct loop *loop, im_mem_ref *ref) |
8f9829e8 | 2304 | { |
2305 | gcc_checking_assert (MEM_ANALYZABLE (ref)); | |
2306 | ||
23298f15 | 2307 | return ref_indep_loop_p_1 (loop, ref, false); |
55a03692 | 2308 | } |
2309 | ||
063a8bce | 2310 | /* Returns true if we can perform store motion of REF from LOOP. */ |
55a03692 | 2311 | |
063a8bce | 2312 | static bool |
4a7ff262 | 2313 | can_sm_ref_p (struct loop *loop, im_mem_ref *ref) |
55a03692 | 2314 | { |
307f7fda | 2315 | tree base; |
2316 | ||
0766b2c0 | 2317 | /* Can't hoist unanalyzable refs. */ |
2318 | if (!MEM_ANALYZABLE (ref)) | |
2319 | return false; | |
2320 | ||
063a8bce | 2321 | /* It should be movable. */ |
09f4cf62 | 2322 | if (!is_gimple_reg_type (TREE_TYPE (ref->mem.ref)) |
2323 | || TREE_THIS_VOLATILE (ref->mem.ref) | |
2324 | || !for_each_index (&ref->mem.ref, may_move_till, loop)) | |
063a8bce | 2325 | return false; |
342ea212 | 2326 | |
16d9b5d8 | 2327 | /* If it can throw fail, we do not properly update EH info. */ |
09f4cf62 | 2328 | if (tree_could_throw_p (ref->mem.ref)) |
16d9b5d8 | 2329 | return false; |
2330 | ||
307f7fda | 2331 | /* If it can trap, it must be always executed in LOOP. |
2332 | Readonly memory locations may trap when storing to them, but | |
2333 | tree_could_trap_p is a predicate for rvalues, so check that | |
2334 | explicitly. */ | |
09f4cf62 | 2335 | base = get_base_address (ref->mem.ref); |
2336 | if ((tree_could_trap_p (ref->mem.ref) | |
307f7fda | 2337 | || (DECL_P (base) && TREE_READONLY (base))) |
2338 | && !ref_always_accessed_p (loop, ref, true)) | |
063a8bce | 2339 | return false; |
342ea212 | 2340 | |
063a8bce | 2341 | /* And it must be independent on all other memory references |
2342 | in LOOP. */ | |
23298f15 | 2343 | if (!ref_indep_loop_p (loop, ref)) |
063a8bce | 2344 | return false; |
342ea212 | 2345 | |
063a8bce | 2346 | return true; |
342ea212 | 2347 | } |
2348 | ||
063a8bce | 2349 | /* Marks the references in LOOP for that store motion should be performed |
2350 | in REFS_TO_SM. SM_EXECUTED is the set of references for that store | |
2351 | motion was performed in one of the outer loops. */ | |
342ea212 | 2352 | |
2353 | static void | |
063a8bce | 2354 | find_refs_for_sm (struct loop *loop, bitmap sm_executed, bitmap refs_to_sm) |
55a03692 | 2355 | { |
feba4360 | 2356 | bitmap refs = &memory_accesses.all_refs_stored_in_loop[loop->num]; |
063a8bce | 2357 | unsigned i; |
2358 | bitmap_iterator bi; | |
4a7ff262 | 2359 | im_mem_ref *ref; |
063a8bce | 2360 | |
2361 | EXECUTE_IF_AND_COMPL_IN_BITMAP (refs, sm_executed, 0, i, bi) | |
2362 | { | |
f1f41a6c | 2363 | ref = memory_accesses.refs_list[i]; |
063a8bce | 2364 | if (can_sm_ref_p (loop, ref)) |
2365 | bitmap_set_bit (refs_to_sm, i); | |
2366 | } | |
342ea212 | 2367 | } |
55a03692 | 2368 | |
063a8bce | 2369 | /* Checks whether LOOP (with exits stored in EXITS array) is suitable |
2370 | for a store motion optimization (i.e. whether we can insert statement | |
2371 | on its exits). */ | |
342ea212 | 2372 | |
063a8bce | 2373 | static bool |
2374 | loop_suitable_for_sm (struct loop *loop ATTRIBUTE_UNUSED, | |
f1f41a6c | 2375 | vec<edge> exits) |
342ea212 | 2376 | { |
063a8bce | 2377 | unsigned i; |
2378 | edge ex; | |
55a03692 | 2379 | |
f1f41a6c | 2380 | FOR_EACH_VEC_ELT (exits, i, ex) |
9102193b | 2381 | if (ex->flags & (EDGE_ABNORMAL | EDGE_EH)) |
063a8bce | 2382 | return false; |
2383 | ||
2384 | return true; | |
55a03692 | 2385 | } |
2386 | ||
7d23383d | 2387 | /* Try to perform store motion for all memory references modified inside |
063a8bce | 2388 | LOOP. SM_EXECUTED is the bitmap of the memory references for that |
2389 | store motion was executed in one of the outer loops. */ | |
7d23383d | 2390 | |
2391 | static void | |
063a8bce | 2392 | store_motion_loop (struct loop *loop, bitmap sm_executed) |
7d23383d | 2393 | { |
f1f41a6c | 2394 | vec<edge> exits = get_loop_exit_edges (loop); |
063a8bce | 2395 | struct loop *subloop; |
39f8afdf | 2396 | bitmap sm_in_loop = BITMAP_ALLOC (&lim_bitmap_obstack); |
7d23383d | 2397 | |
063a8bce | 2398 | if (loop_suitable_for_sm (loop, exits)) |
7d23383d | 2399 | { |
063a8bce | 2400 | find_refs_for_sm (loop, sm_executed, sm_in_loop); |
2401 | hoist_memory_references (loop, sm_in_loop, exits); | |
7d23383d | 2402 | } |
f1f41a6c | 2403 | exits.release (); |
063a8bce | 2404 | |
2405 | bitmap_ior_into (sm_executed, sm_in_loop); | |
2406 | for (subloop = loop->inner; subloop != NULL; subloop = subloop->next) | |
2407 | store_motion_loop (subloop, sm_executed); | |
2408 | bitmap_and_compl_into (sm_executed, sm_in_loop); | |
2409 | BITMAP_FREE (sm_in_loop); | |
7d23383d | 2410 | } |
2411 | ||
2412 | /* Try to perform store motion for all memory references modified inside | |
7194de72 | 2413 | loops. */ |
7d23383d | 2414 | |
2415 | static void | |
063a8bce | 2416 | store_motion (void) |
7d23383d | 2417 | { |
2418 | struct loop *loop; | |
39f8afdf | 2419 | bitmap sm_executed = BITMAP_ALLOC (&lim_bitmap_obstack); |
dda28f7c | 2420 | |
063a8bce | 2421 | for (loop = current_loops->tree_root->inner; loop != NULL; loop = loop->next) |
2422 | store_motion_loop (loop, sm_executed); | |
17519ba0 | 2423 | |
063a8bce | 2424 | BITMAP_FREE (sm_executed); |
75a70cf9 | 2425 | gsi_commit_edge_inserts (); |
7d23383d | 2426 | } |
2427 | ||
2428 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks of LOOP, i.e. | |
2429 | for each such basic block bb records the outermost loop for that execution | |
2430 | of its header implies execution of bb. CONTAINS_CALL is the bitmap of | |
2431 | blocks that contain a nonpure call. */ | |
2432 | ||
2433 | static void | |
feba4360 | 2434 | fill_always_executed_in_1 (struct loop *loop, sbitmap contains_call) |
7d23383d | 2435 | { |
2436 | basic_block bb = NULL, *bbs, last = NULL; | |
2437 | unsigned i; | |
2438 | edge e; | |
2439 | struct loop *inn_loop = loop; | |
2440 | ||
2fd20c29 | 2441 | if (ALWAYS_EXECUTED_IN (loop->header) == NULL) |
7d23383d | 2442 | { |
2443 | bbs = get_loop_body_in_dom_order (loop); | |
2444 | ||
2445 | for (i = 0; i < loop->num_nodes; i++) | |
2446 | { | |
cd665a06 | 2447 | edge_iterator ei; |
7d23383d | 2448 | bb = bbs[i]; |
2449 | ||
2450 | if (dominated_by_p (CDI_DOMINATORS, loop->latch, bb)) | |
2451 | last = bb; | |
2452 | ||
08b7917c | 2453 | if (bitmap_bit_p (contains_call, bb->index)) |
7d23383d | 2454 | break; |
2455 | ||
cd665a06 | 2456 | FOR_EACH_EDGE (e, ei, bb->succs) |
5b9b62c9 | 2457 | { |
2458 | /* If there is an exit from this BB. */ | |
2459 | if (!flow_bb_inside_loop_p (loop, e->dest)) | |
2460 | break; | |
2461 | /* Or we enter a possibly non-finite loop. */ | |
2462 | if (flow_loop_nested_p (bb->loop_father, | |
2463 | e->dest->loop_father) | |
2464 | && ! finite_loop_p (e->dest->loop_father)) | |
2465 | break; | |
2466 | } | |
7d23383d | 2467 | if (e) |
2468 | break; | |
2469 | ||
2470 | /* A loop might be infinite (TODO use simple loop analysis | |
2471 | to disprove this if possible). */ | |
2472 | if (bb->flags & BB_IRREDUCIBLE_LOOP) | |
2473 | break; | |
2474 | ||
2475 | if (!flow_bb_inside_loop_p (inn_loop, bb)) | |
2476 | break; | |
2477 | ||
2478 | if (bb->loop_father->header == bb) | |
2479 | { | |
2480 | if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb)) | |
2481 | break; | |
2482 | ||
2483 | /* In a loop that is always entered we may proceed anyway. | |
2484 | But record that we entered it and stop once we leave it. */ | |
2485 | inn_loop = bb->loop_father; | |
2486 | } | |
2487 | } | |
2488 | ||
2489 | while (1) | |
2490 | { | |
2fd20c29 | 2491 | SET_ALWAYS_EXECUTED_IN (last, loop); |
7d23383d | 2492 | if (last == loop->header) |
2493 | break; | |
2494 | last = get_immediate_dominator (CDI_DOMINATORS, last); | |
2495 | } | |
2496 | ||
2497 | free (bbs); | |
2498 | } | |
2499 | ||
2500 | for (loop = loop->inner; loop; loop = loop->next) | |
feba4360 | 2501 | fill_always_executed_in_1 (loop, contains_call); |
7d23383d | 2502 | } |
2503 | ||
feba4360 | 2504 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks, i.e. |
2505 | for each such basic block bb records the outermost loop for that execution | |
2506 | of its header implies execution of bb. */ | |
7d23383d | 2507 | |
2508 | static void | |
feba4360 | 2509 | fill_always_executed_in (void) |
7d23383d | 2510 | { |
7d23383d | 2511 | basic_block bb; |
feba4360 | 2512 | struct loop *loop; |
4fb07d00 | 2513 | |
3c6549f8 | 2514 | auto_sbitmap contains_call (last_basic_block_for_fn (cfun)); |
53c5d9d4 | 2515 | bitmap_clear (contains_call); |
fc00614f | 2516 | FOR_EACH_BB_FN (bb, cfun) |
7d23383d | 2517 | { |
feba4360 | 2518 | gimple_stmt_iterator gsi; |
2519 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
7d23383d | 2520 | { |
feba4360 | 2521 | if (nonpure_call_p (gsi_stmt (gsi))) |
7d23383d | 2522 | break; |
2523 | } | |
2524 | ||
feba4360 | 2525 | if (!gsi_end_p (gsi)) |
08b7917c | 2526 | bitmap_set_bit (contains_call, bb->index); |
7d23383d | 2527 | } |
2528 | ||
7194de72 | 2529 | for (loop = current_loops->tree_root->inner; loop; loop = loop->next) |
feba4360 | 2530 | fill_always_executed_in_1 (loop, contains_call); |
feba4360 | 2531 | } |
2532 | ||
2533 | ||
2534 | /* Compute the global information needed by the loop invariant motion pass. */ | |
75a70cf9 | 2535 | |
feba4360 | 2536 | static void |
2537 | tree_ssa_lim_initialize (void) | |
2538 | { | |
3e48928c | 2539 | struct loop *loop; |
feba4360 | 2540 | unsigned i; |
2541 | ||
2542 | bitmap_obstack_initialize (&lim_bitmap_obstack); | |
3e48928c | 2543 | gcc_obstack_init (&mem_ref_obstack); |
42acab1c | 2544 | lim_aux_data_map = new hash_map<gimple *, lim_aux_data *>; |
de60f90c | 2545 | |
2546 | if (flag_tm) | |
2547 | compute_transaction_bits (); | |
61025ec0 | 2548 | |
2549 | alloc_aux_for_edges (0); | |
feba4360 | 2550 | |
c1f445d2 | 2551 | memory_accesses.refs = new hash_table<mem_ref_hasher> (100); |
feba4360 | 2552 | memory_accesses.refs_list.create (100); |
2553 | /* Allocate a special, unanalyzable mem-ref with ID zero. */ | |
2554 | memory_accesses.refs_list.quick_push | |
1b94b295 | 2555 | (mem_ref_alloc (NULL, 0, UNANALYZABLE_MEM_ID)); |
feba4360 | 2556 | |
41f75a99 | 2557 | memory_accesses.refs_in_loop.create (number_of_loops (cfun)); |
2558 | memory_accesses.refs_in_loop.quick_grow (number_of_loops (cfun)); | |
2559 | memory_accesses.refs_stored_in_loop.create (number_of_loops (cfun)); | |
2560 | memory_accesses.refs_stored_in_loop.quick_grow (number_of_loops (cfun)); | |
2561 | memory_accesses.all_refs_stored_in_loop.create (number_of_loops (cfun)); | |
2562 | memory_accesses.all_refs_stored_in_loop.quick_grow (number_of_loops (cfun)); | |
feba4360 | 2563 | |
41f75a99 | 2564 | for (i = 0; i < number_of_loops (cfun); i++) |
feba4360 | 2565 | { |
2566 | bitmap_initialize (&memory_accesses.refs_in_loop[i], | |
2567 | &lim_bitmap_obstack); | |
2568 | bitmap_initialize (&memory_accesses.refs_stored_in_loop[i], | |
2569 | &lim_bitmap_obstack); | |
2570 | bitmap_initialize (&memory_accesses.all_refs_stored_in_loop[i], | |
2571 | &lim_bitmap_obstack); | |
2572 | } | |
2573 | ||
2574 | memory_accesses.ttae_cache = NULL; | |
3e48928c | 2575 | |
2576 | /* Initialize bb_loop_postorder with a mapping from loop->num to | |
2577 | its postorder index. */ | |
2578 | i = 0; | |
2579 | bb_loop_postorder = XNEWVEC (unsigned, number_of_loops (cfun)); | |
2580 | FOR_EACH_LOOP (loop, LI_FROM_INNERMOST) | |
2581 | bb_loop_postorder[loop->num] = i++; | |
7d23383d | 2582 | } |
2583 | ||
2584 | /* Cleans up after the invariant motion pass. */ | |
2585 | ||
2586 | static void | |
2587 | tree_ssa_lim_finalize (void) | |
2588 | { | |
2589 | basic_block bb; | |
063a8bce | 2590 | unsigned i; |
4a7ff262 | 2591 | im_mem_ref *ref; |
7d23383d | 2592 | |
61025ec0 | 2593 | free_aux_for_edges (); |
2594 | ||
fc00614f | 2595 | FOR_EACH_BB_FN (bb, cfun) |
2fd20c29 | 2596 | SET_ALWAYS_EXECUTED_IN (bb, NULL); |
063a8bce | 2597 | |
4fb07d00 | 2598 | bitmap_obstack_release (&lim_bitmap_obstack); |
06ecf488 | 2599 | delete lim_aux_data_map; |
75a70cf9 | 2600 | |
c1f445d2 | 2601 | delete memory_accesses.refs; |
2602 | memory_accesses.refs = NULL; | |
063a8bce | 2603 | |
f1f41a6c | 2604 | FOR_EACH_VEC_ELT (memory_accesses.refs_list, i, ref) |
83b709f2 | 2605 | memref_free (ref); |
f1f41a6c | 2606 | memory_accesses.refs_list.release (); |
3e48928c | 2607 | obstack_free (&mem_ref_obstack, NULL); |
83b709f2 | 2608 | |
f1f41a6c | 2609 | memory_accesses.refs_in_loop.release (); |
8f9829e8 | 2610 | memory_accesses.refs_stored_in_loop.release (); |
f1f41a6c | 2611 | memory_accesses.all_refs_stored_in_loop.release (); |
063a8bce | 2612 | |
2613 | if (memory_accesses.ttae_cache) | |
78d53e33 | 2614 | free_affine_expand_cache (&memory_accesses.ttae_cache); |
3e48928c | 2615 | |
2616 | free (bb_loop_postorder); | |
7d23383d | 2617 | } |
2618 | ||
7194de72 | 2619 | /* Moves invariants from loops. Only "expensive" invariants are moved out -- |
7d23383d | 2620 | i.e. those that are likely to be win regardless of the register pressure. */ |
2621 | ||
b11dc37d | 2622 | static unsigned int |
7194de72 | 2623 | tree_ssa_lim (void) |
7d23383d | 2624 | { |
9bf0a3f9 | 2625 | unsigned int todo; |
2626 | ||
7194de72 | 2627 | tree_ssa_lim_initialize (); |
7d23383d | 2628 | |
063a8bce | 2629 | /* Gathers information about memory accesses in the loops. */ |
2630 | analyze_memory_references (); | |
2631 | ||
feba4360 | 2632 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks. */ |
2633 | fill_always_executed_in (); | |
2634 | ||
7d23383d | 2635 | /* For each statement determine the outermost loop in that it is |
2636 | invariant and cost for computing the invariant. */ | |
54c91640 | 2637 | invariantness_dom_walker (CDI_DOMINATORS) |
2638 | .walk (cfun->cfg->x_entry_block_ptr); | |
7d23383d | 2639 | |
063a8bce | 2640 | /* Execute store motion. Force the necessary invariants to be moved |
2641 | out of the loops as well. */ | |
2642 | store_motion (); | |
7d23383d | 2643 | |
2644 | /* Move the expressions that are expensive enough. */ | |
9bf0a3f9 | 2645 | todo = move_computations (); |
7d23383d | 2646 | |
2647 | tree_ssa_lim_finalize (); | |
9bf0a3f9 | 2648 | |
2649 | return todo; | |
7d23383d | 2650 | } |
f86b328b | 2651 | |
2652 | /* Loop invariant motion pass. */ | |
2653 | ||
f86b328b | 2654 | namespace { |
2655 | ||
2656 | const pass_data pass_data_lim = | |
2657 | { | |
2658 | GIMPLE_PASS, /* type */ | |
2659 | "lim", /* name */ | |
2660 | OPTGROUP_LOOP, /* optinfo_flags */ | |
f86b328b | 2661 | TV_LIM, /* tv_id */ |
2662 | PROP_cfg, /* properties_required */ | |
2663 | 0, /* properties_provided */ | |
2664 | 0, /* properties_destroyed */ | |
2665 | 0, /* todo_flags_start */ | |
2666 | 0, /* todo_flags_finish */ | |
2667 | }; | |
2668 | ||
2669 | class pass_lim : public gimple_opt_pass | |
2670 | { | |
2671 | public: | |
2672 | pass_lim (gcc::context *ctxt) | |
2673 | : gimple_opt_pass (pass_data_lim, ctxt) | |
2674 | {} | |
2675 | ||
2676 | /* opt_pass methods: */ | |
2677 | opt_pass * clone () { return new pass_lim (m_ctxt); } | |
31315c24 | 2678 | virtual bool gate (function *) { return flag_tree_loop_im != 0; } |
65b0537f | 2679 | virtual unsigned int execute (function *); |
f86b328b | 2680 | |
2681 | }; // class pass_lim | |
2682 | ||
65b0537f | 2683 | unsigned int |
2684 | pass_lim::execute (function *fun) | |
2685 | { | |
b11dc37d | 2686 | bool in_loop_pipeline = scev_initialized_p (); |
2687 | if (!in_loop_pipeline) | |
2688 | loop_optimizer_init (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS); | |
2689 | ||
65b0537f | 2690 | if (number_of_loops (fun) <= 1) |
2691 | return 0; | |
b11dc37d | 2692 | unsigned int todo = tree_ssa_lim (); |
65b0537f | 2693 | |
b11dc37d | 2694 | if (!in_loop_pipeline) |
2695 | loop_optimizer_finalize (); | |
9b33fe18 | 2696 | else |
2697 | scev_reset (); | |
b11dc37d | 2698 | return todo; |
65b0537f | 2699 | } |
2700 | ||
f86b328b | 2701 | } // anon namespace |
2702 | ||
2703 | gimple_opt_pass * | |
2704 | make_pass_lim (gcc::context *ctxt) | |
2705 | { | |
2706 | return new pass_lim (ctxt); | |
2707 | } | |
2708 | ||
2709 |