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7d23383d | 1 | /* Loop invariant motion. |
d353bf18 | 2 | Copyright (C) 2003-2015 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" | |
23 | #include "tm.h" | |
b20a8bb4 | 24 | #include "hash-set.h" |
b20a8bb4 | 25 | #include "vec.h" |
b20a8bb4 | 26 | #include "input.h" |
27 | #include "alias.h" | |
28 | #include "symtab.h" | |
b20a8bb4 | 29 | #include "inchash.h" |
7d23383d | 30 | #include "tree.h" |
b20a8bb4 | 31 | #include "fold-const.h" |
7d23383d | 32 | #include "tm_p.h" |
94ea8568 | 33 | #include "predict.h" |
94ea8568 | 34 | #include "hard-reg-set.h" |
35 | #include "input.h" | |
36 | #include "function.h" | |
37 | #include "dominance.h" | |
38 | #include "cfg.h" | |
39 | #include "cfganal.h" | |
7d23383d | 40 | #include "basic-block.h" |
8e3cb73b | 41 | #include "gimple-pretty-print.h" |
06ecf488 | 42 | #include "hash-map.h" |
bc61cadb | 43 | #include "hash-table.h" |
44 | #include "tree-ssa-alias.h" | |
45 | #include "internal-fn.h" | |
46 | #include "tree-eh.h" | |
47 | #include "gimple-expr.h" | |
48 | #include "is-a.h" | |
073c1fd5 | 49 | #include "gimple.h" |
a8783bee | 50 | #include "gimplify.h" |
dcf1a1ec | 51 | #include "gimple-iterator.h" |
073c1fd5 | 52 | #include "gimple-ssa.h" |
53 | #include "tree-cfg.h" | |
54 | #include "tree-phinodes.h" | |
55 | #include "ssa-iterators.h" | |
9ed99284 | 56 | #include "stringpool.h" |
073c1fd5 | 57 | #include "tree-ssanames.h" |
05d9c18a | 58 | #include "tree-ssa-loop-manip.h" |
073c1fd5 | 59 | #include "tree-ssa-loop.h" |
60 | #include "tree-into-ssa.h" | |
7d23383d | 61 | #include "cfgloop.h" |
62 | #include "domwalk.h" | |
63 | #include "params.h" | |
64 | #include "tree-pass.h" | |
65 | #include "flags.h" | |
063a8bce | 66 | #include "tree-affine.h" |
a973ed42 | 67 | #include "tree-ssa-propagate.h" |
e797f49f | 68 | #include "trans-mem.h" |
f6a34e3f | 69 | #include "gimple-fold.h" |
7d23383d | 70 | |
ca53beb1 | 71 | /* TODO: Support for predicated code motion. I.e. |
72 | ||
73 | while (1) | |
74 | { | |
75 | if (cond) | |
76 | { | |
77 | a = inv; | |
78 | something; | |
79 | } | |
80 | } | |
81 | ||
61025ec0 | 82 | Where COND and INV are invariants, but evaluating INV may trap or be |
ca53beb1 | 83 | invalid from some other reason if !COND. This may be transformed to |
84 | ||
85 | if (cond) | |
86 | a = inv; | |
87 | while (1) | |
88 | { | |
89 | if (cond) | |
90 | something; | |
91 | } */ | |
92 | ||
7d23383d | 93 | /* The auxiliary data kept for each statement. */ |
94 | ||
95 | struct lim_aux_data | |
96 | { | |
97 | struct loop *max_loop; /* The outermost loop in that the statement | |
98 | is invariant. */ | |
99 | ||
100 | struct loop *tgt_loop; /* The loop out of that we want to move the | |
101 | invariant. */ | |
102 | ||
103 | struct loop *always_executed_in; | |
104 | /* The outermost loop for that we are sure | |
105 | the statement is executed if the loop | |
106 | is entered. */ | |
107 | ||
7d23383d | 108 | unsigned cost; /* Cost of the computation performed by the |
109 | statement. */ | |
110 | ||
a2c22c0d | 111 | vec<gimple> depends; /* Vector of statements that must be also |
112 | hoisted out of the loop when this statement | |
113 | is hoisted; i.e. those that define the | |
114 | operands of the statement and are inside of | |
115 | the MAX_LOOP loop. */ | |
7d23383d | 116 | }; |
117 | ||
75a70cf9 | 118 | /* Maps statements to their lim_aux_data. */ |
119 | ||
06ecf488 | 120 | static hash_map<gimple, lim_aux_data *> *lim_aux_data_map; |
7d23383d | 121 | |
063a8bce | 122 | /* Description of a memory reference location. */ |
7d23383d | 123 | |
063a8bce | 124 | typedef struct mem_ref_loc |
7d23383d | 125 | { |
126 | tree *ref; /* The reference itself. */ | |
75a70cf9 | 127 | gimple stmt; /* The statement in that it occurs. */ |
063a8bce | 128 | } *mem_ref_loc_p; |
129 | ||
063a8bce | 130 | |
063a8bce | 131 | /* Description of a memory reference. */ |
132 | ||
1ada9901 | 133 | typedef struct im_mem_ref |
55a03692 | 134 | { |
063a8bce | 135 | unsigned id; /* ID assigned to the memory reference |
136 | (its index in memory_accesses.refs_list) */ | |
55a03692 | 137 | hashval_t hash; /* Its hash value. */ |
09f4cf62 | 138 | |
139 | /* The memory access itself and associated caching of alias-oracle | |
140 | query meta-data. */ | |
141 | ao_ref mem; | |
142 | ||
3e48928c | 143 | bitmap stored; /* The set of loops in that this memory location |
063a8bce | 144 | is stored to. */ |
3e48928c | 145 | vec<mem_ref_loc> accesses_in_loop; |
063a8bce | 146 | /* The locations of the accesses. Vector |
147 | indexed by the loop number. */ | |
063a8bce | 148 | |
149 | /* The following sets are computed on demand. We keep both set and | |
150 | its complement, so that we know whether the information was | |
151 | already computed or not. */ | |
feba4360 | 152 | bitmap_head indep_loop; /* The set of loops in that the memory |
063a8bce | 153 | reference is independent, meaning: |
154 | If it is stored in the loop, this store | |
155 | is independent on all other loads and | |
156 | stores. | |
157 | If it is only loaded, then it is independent | |
158 | on all stores in the loop. */ | |
feba4360 | 159 | bitmap_head dep_loop; /* The complement of INDEP_LOOP. */ |
063a8bce | 160 | } *mem_ref_p; |
161 | ||
8f9829e8 | 162 | /* We use two bits per loop in the ref->{in,}dep_loop bitmaps, the first |
163 | to record (in)dependence against stores in the loop and its subloops, the | |
164 | second to record (in)dependence against all references in the loop | |
165 | and its subloops. */ | |
166 | #define LOOP_DEP_BIT(loopnum, storedp) (2 * (loopnum) + (storedp ? 1 : 0)) | |
063a8bce | 167 | |
3e871d4d | 168 | /* Mem_ref hashtable helpers. */ |
169 | ||
1ada9901 | 170 | struct mem_ref_hasher : typed_noop_remove <im_mem_ref> |
3e871d4d | 171 | { |
9969c043 | 172 | typedef im_mem_ref *value_type; |
173 | typedef tree_node *compare_type; | |
174 | static inline hashval_t hash (const im_mem_ref *); | |
175 | static inline bool equal (const im_mem_ref *, const tree_node *); | |
3e871d4d | 176 | }; |
177 | ||
1ada9901 | 178 | /* A hash function for struct im_mem_ref object OBJ. */ |
3e871d4d | 179 | |
180 | inline hashval_t | |
9969c043 | 181 | mem_ref_hasher::hash (const im_mem_ref *mem) |
3e871d4d | 182 | { |
183 | return mem->hash; | |
184 | } | |
185 | ||
1ada9901 | 186 | /* An equality function for struct im_mem_ref object MEM1 with |
3e871d4d | 187 | memory reference OBJ2. */ |
188 | ||
189 | inline bool | |
9969c043 | 190 | mem_ref_hasher::equal (const im_mem_ref *mem1, const tree_node *obj2) |
3e871d4d | 191 | { |
192 | return operand_equal_p (mem1->mem.ref, (const_tree) obj2, 0); | |
193 | } | |
063a8bce | 194 | |
063a8bce | 195 | |
196 | /* Description of memory accesses in loops. */ | |
197 | ||
198 | static struct | |
199 | { | |
200 | /* The hash table of memory references accessed in loops. */ | |
c1f445d2 | 201 | hash_table<mem_ref_hasher> *refs; |
063a8bce | 202 | |
203 | /* The list of memory references. */ | |
f1f41a6c | 204 | vec<mem_ref_p> refs_list; |
063a8bce | 205 | |
206 | /* The set of memory references accessed in each loop. */ | |
feba4360 | 207 | vec<bitmap_head> refs_in_loop; |
063a8bce | 208 | |
8f9829e8 | 209 | /* The set of memory references stored in each loop. */ |
feba4360 | 210 | vec<bitmap_head> refs_stored_in_loop; |
8f9829e8 | 211 | |
8f9829e8 | 212 | /* The set of memory references stored in each loop, including subloops . */ |
feba4360 | 213 | vec<bitmap_head> all_refs_stored_in_loop; |
063a8bce | 214 | |
215 | /* Cache for expanding memory addresses. */ | |
5f8841a5 | 216 | hash_map<tree, name_expansion *> *ttae_cache; |
063a8bce | 217 | } memory_accesses; |
218 | ||
4fb07d00 | 219 | /* Obstack for the bitmaps in the above data structures. */ |
220 | static bitmap_obstack lim_bitmap_obstack; | |
3e48928c | 221 | static obstack mem_ref_obstack; |
4fb07d00 | 222 | |
063a8bce | 223 | static bool ref_indep_loop_p (struct loop *, mem_ref_p); |
7d23383d | 224 | |
225 | /* Minimum cost of an expensive expression. */ | |
226 | #define LIM_EXPENSIVE ((unsigned) PARAM_VALUE (PARAM_LIM_EXPENSIVE)) | |
227 | ||
2fd20c29 | 228 | /* The outermost loop for which execution of the header guarantees that the |
7d23383d | 229 | block will be executed. */ |
230 | #define ALWAYS_EXECUTED_IN(BB) ((struct loop *) (BB)->aux) | |
2fd20c29 | 231 | #define SET_ALWAYS_EXECUTED_IN(BB, VAL) ((BB)->aux = (void *) (VAL)) |
7d23383d | 232 | |
04911505 | 233 | /* ID of the shared unanalyzable mem. */ |
234 | #define UNANALYZABLE_MEM_ID 0 | |
235 | ||
0766b2c0 | 236 | /* Whether the reference was analyzable. */ |
04911505 | 237 | #define MEM_ANALYZABLE(REF) ((REF)->id != UNANALYZABLE_MEM_ID) |
0766b2c0 | 238 | |
75a70cf9 | 239 | static struct lim_aux_data * |
240 | init_lim_data (gimple stmt) | |
241 | { | |
06ecf488 | 242 | lim_aux_data *p = XCNEW (struct lim_aux_data); |
243 | lim_aux_data_map->put (stmt, p); | |
75a70cf9 | 244 | |
06ecf488 | 245 | return p; |
75a70cf9 | 246 | } |
247 | ||
248 | static struct lim_aux_data * | |
249 | get_lim_data (gimple stmt) | |
250 | { | |
06ecf488 | 251 | lim_aux_data **p = lim_aux_data_map->get (stmt); |
75a70cf9 | 252 | if (!p) |
253 | return NULL; | |
254 | ||
06ecf488 | 255 | return *p; |
75a70cf9 | 256 | } |
257 | ||
258 | /* Releases the memory occupied by DATA. */ | |
259 | ||
260 | static void | |
261 | free_lim_aux_data (struct lim_aux_data *data) | |
262 | { | |
9af5ce0c | 263 | data->depends.release (); |
75a70cf9 | 264 | free (data); |
265 | } | |
266 | ||
267 | static void | |
268 | clear_lim_data (gimple stmt) | |
269 | { | |
06ecf488 | 270 | lim_aux_data **p = lim_aux_data_map->get (stmt); |
75a70cf9 | 271 | if (!p) |
272 | return; | |
273 | ||
06ecf488 | 274 | free_lim_aux_data (*p); |
75a70cf9 | 275 | *p = NULL; |
276 | } | |
277 | ||
48e1416a | 278 | |
f86b328b | 279 | /* The possibilities of statement movement. */ |
280 | enum move_pos | |
281 | { | |
282 | MOVE_IMPOSSIBLE, /* No movement -- side effect expression. */ | |
283 | MOVE_PRESERVE_EXECUTION, /* Must not cause the non-executed statement | |
284 | become executed -- memory accesses, ... */ | |
285 | MOVE_POSSIBLE /* Unlimited movement. */ | |
286 | }; | |
aed164c3 | 287 | |
7d23383d | 288 | |
289 | /* If it is possible to hoist the statement STMT unconditionally, | |
290 | returns MOVE_POSSIBLE. | |
291 | If it is possible to hoist the statement STMT, but we must avoid making | |
292 | it executed if it would not be executed in the original program (e.g. | |
293 | because it may trap), return MOVE_PRESERVE_EXECUTION. | |
294 | Otherwise return MOVE_IMPOSSIBLE. */ | |
295 | ||
07c03fb0 | 296 | enum move_pos |
75a70cf9 | 297 | movement_possibility (gimple stmt) |
7d23383d | 298 | { |
75a70cf9 | 299 | tree lhs; |
300 | enum move_pos ret = MOVE_POSSIBLE; | |
7d23383d | 301 | |
302 | if (flag_unswitch_loops | |
75a70cf9 | 303 | && gimple_code (stmt) == GIMPLE_COND) |
7d23383d | 304 | { |
305 | /* If we perform unswitching, force the operands of the invariant | |
306 | condition to be moved out of the loop. */ | |
7d23383d | 307 | return MOVE_POSSIBLE; |
308 | } | |
309 | ||
9bf0a3f9 | 310 | if (gimple_code (stmt) == GIMPLE_PHI |
311 | && gimple_phi_num_args (stmt) <= 2 | |
7c782c9b | 312 | && !virtual_operand_p (gimple_phi_result (stmt)) |
9bf0a3f9 | 313 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_phi_result (stmt))) |
314 | return MOVE_POSSIBLE; | |
315 | ||
75a70cf9 | 316 | if (gimple_get_lhs (stmt) == NULL_TREE) |
7d23383d | 317 | return MOVE_IMPOSSIBLE; |
318 | ||
dd277d48 | 319 | if (gimple_vdef (stmt)) |
063a8bce | 320 | return MOVE_IMPOSSIBLE; |
321 | ||
75a70cf9 | 322 | if (stmt_ends_bb_p (stmt) |
323 | || gimple_has_volatile_ops (stmt) | |
324 | || gimple_has_side_effects (stmt) | |
325 | || stmt_could_throw_p (stmt)) | |
7d23383d | 326 | return MOVE_IMPOSSIBLE; |
327 | ||
75a70cf9 | 328 | if (is_gimple_call (stmt)) |
ca53beb1 | 329 | { |
330 | /* While pure or const call is guaranteed to have no side effects, we | |
331 | cannot move it arbitrarily. Consider code like | |
332 | ||
333 | char *s = something (); | |
334 | ||
335 | while (1) | |
336 | { | |
337 | if (s) | |
338 | t = strlen (s); | |
339 | else | |
340 | t = 0; | |
341 | } | |
342 | ||
343 | Here the strlen call cannot be moved out of the loop, even though | |
344 | s is invariant. In addition to possibly creating a call with | |
345 | invalid arguments, moving out a function call that is not executed | |
346 | may cause performance regressions in case the call is costly and | |
347 | not executed at all. */ | |
75a70cf9 | 348 | ret = MOVE_PRESERVE_EXECUTION; |
349 | lhs = gimple_call_lhs (stmt); | |
ca53beb1 | 350 | } |
75a70cf9 | 351 | else if (is_gimple_assign (stmt)) |
352 | lhs = gimple_assign_lhs (stmt); | |
353 | else | |
354 | return MOVE_IMPOSSIBLE; | |
355 | ||
356 | if (TREE_CODE (lhs) == SSA_NAME | |
357 | && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) | |
358 | return MOVE_IMPOSSIBLE; | |
359 | ||
360 | if (TREE_CODE (lhs) != SSA_NAME | |
361 | || gimple_could_trap_p (stmt)) | |
362 | return MOVE_PRESERVE_EXECUTION; | |
363 | ||
de60f90c | 364 | /* Non local loads in a transaction cannot be hoisted out. Well, |
365 | unless the load happens on every path out of the loop, but we | |
366 | don't take this into account yet. */ | |
367 | if (flag_tm | |
368 | && gimple_in_transaction (stmt) | |
369 | && gimple_assign_single_p (stmt)) | |
370 | { | |
371 | tree rhs = gimple_assign_rhs1 (stmt); | |
372 | if (DECL_P (rhs) && is_global_var (rhs)) | |
373 | { | |
374 | if (dump_file) | |
375 | { | |
376 | fprintf (dump_file, "Cannot hoist conditional load of "); | |
377 | print_generic_expr (dump_file, rhs, TDF_SLIM); | |
378 | fprintf (dump_file, " because it is in a transaction.\n"); | |
379 | } | |
380 | return MOVE_IMPOSSIBLE; | |
381 | } | |
382 | } | |
383 | ||
75a70cf9 | 384 | return ret; |
7d23383d | 385 | } |
386 | ||
387 | /* Suppose that operand DEF is used inside the LOOP. Returns the outermost | |
91275768 | 388 | loop to that we could move the expression using DEF if it did not have |
7d23383d | 389 | other operands, i.e. the outermost loop enclosing LOOP in that the value |
390 | of DEF is invariant. */ | |
391 | ||
392 | static struct loop * | |
393 | outermost_invariant_loop (tree def, struct loop *loop) | |
394 | { | |
75a70cf9 | 395 | gimple def_stmt; |
7d23383d | 396 | basic_block def_bb; |
397 | struct loop *max_loop; | |
75a70cf9 | 398 | struct lim_aux_data *lim_data; |
7d23383d | 399 | |
75a70cf9 | 400 | if (!def) |
7d23383d | 401 | return superloop_at_depth (loop, 1); |
402 | ||
75a70cf9 | 403 | if (TREE_CODE (def) != SSA_NAME) |
404 | { | |
405 | gcc_assert (is_gimple_min_invariant (def)); | |
406 | return superloop_at_depth (loop, 1); | |
407 | } | |
408 | ||
7d23383d | 409 | def_stmt = SSA_NAME_DEF_STMT (def); |
75a70cf9 | 410 | def_bb = gimple_bb (def_stmt); |
7d23383d | 411 | if (!def_bb) |
412 | return superloop_at_depth (loop, 1); | |
413 | ||
414 | max_loop = find_common_loop (loop, def_bb->loop_father); | |
415 | ||
75a70cf9 | 416 | lim_data = get_lim_data (def_stmt); |
417 | if (lim_data != NULL && lim_data->max_loop != NULL) | |
7d23383d | 418 | max_loop = find_common_loop (max_loop, |
75a70cf9 | 419 | loop_outer (lim_data->max_loop)); |
7d23383d | 420 | if (max_loop == loop) |
421 | return NULL; | |
9e3536f4 | 422 | max_loop = superloop_at_depth (loop, loop_depth (max_loop) + 1); |
7d23383d | 423 | |
424 | return max_loop; | |
425 | } | |
426 | ||
7d23383d | 427 | /* DATA is a structure containing information associated with a statement |
428 | inside LOOP. DEF is one of the operands of this statement. | |
48e1416a | 429 | |
7d23383d | 430 | Find the outermost loop enclosing LOOP in that value of DEF is invariant |
431 | and record this in DATA->max_loop field. If DEF itself is defined inside | |
432 | this loop as well (i.e. we need to hoist it out of the loop if we want | |
433 | to hoist the statement represented by DATA), record the statement in that | |
434 | DEF is defined to the DATA->depends list. Additionally if ADD_COST is true, | |
435 | add the cost of the computation of DEF to the DATA->cost. | |
48e1416a | 436 | |
7d23383d | 437 | If DEF is not invariant in LOOP, return false. Otherwise return TRUE. */ |
438 | ||
439 | static bool | |
440 | add_dependency (tree def, struct lim_aux_data *data, struct loop *loop, | |
441 | bool add_cost) | |
442 | { | |
75a70cf9 | 443 | gimple def_stmt = SSA_NAME_DEF_STMT (def); |
444 | basic_block def_bb = gimple_bb (def_stmt); | |
7d23383d | 445 | struct loop *max_loop; |
75a70cf9 | 446 | struct lim_aux_data *def_data; |
7d23383d | 447 | |
448 | if (!def_bb) | |
449 | return true; | |
450 | ||
451 | max_loop = outermost_invariant_loop (def, loop); | |
452 | if (!max_loop) | |
453 | return false; | |
454 | ||
455 | if (flow_loop_nested_p (data->max_loop, max_loop)) | |
456 | data->max_loop = max_loop; | |
457 | ||
75a70cf9 | 458 | def_data = get_lim_data (def_stmt); |
459 | if (!def_data) | |
7d23383d | 460 | return true; |
461 | ||
462 | if (add_cost | |
463 | /* Only add the cost if the statement defining DEF is inside LOOP, | |
464 | i.e. if it is likely that by moving the invariants dependent | |
465 | on it, we will be able to avoid creating a new register for | |
466 | it (since it will be only used in these dependent invariants). */ | |
467 | && def_bb->loop_father == loop) | |
75a70cf9 | 468 | data->cost += def_data->cost; |
7d23383d | 469 | |
a2c22c0d | 470 | data->depends.safe_push (def_stmt); |
7d23383d | 471 | |
472 | return true; | |
473 | } | |
474 | ||
0766b2c0 | 475 | /* Returns an estimate for a cost of statement STMT. The values here |
476 | are just ad-hoc constants, similar to costs for inlining. */ | |
7d23383d | 477 | |
478 | static unsigned | |
75a70cf9 | 479 | stmt_cost (gimple stmt) |
7d23383d | 480 | { |
7d23383d | 481 | /* Always try to create possibilities for unswitching. */ |
9bf0a3f9 | 482 | if (gimple_code (stmt) == GIMPLE_COND |
483 | || gimple_code (stmt) == GIMPLE_PHI) | |
7d23383d | 484 | return LIM_EXPENSIVE; |
485 | ||
0766b2c0 | 486 | /* We should be hoisting calls if possible. */ |
75a70cf9 | 487 | if (is_gimple_call (stmt)) |
7d23383d | 488 | { |
0766b2c0 | 489 | tree fndecl; |
7d23383d | 490 | |
491 | /* Unless the call is a builtin_constant_p; this always folds to a | |
492 | constant, so moving it is useless. */ | |
75a70cf9 | 493 | fndecl = gimple_call_fndecl (stmt); |
494 | if (fndecl | |
495 | && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL | |
496 | && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P) | |
7d23383d | 497 | return 0; |
498 | ||
0766b2c0 | 499 | return LIM_EXPENSIVE; |
75a70cf9 | 500 | } |
501 | ||
0766b2c0 | 502 | /* Hoisting memory references out should almost surely be a win. */ |
503 | if (gimple_references_memory_p (stmt)) | |
504 | return LIM_EXPENSIVE; | |
505 | ||
75a70cf9 | 506 | if (gimple_code (stmt) != GIMPLE_ASSIGN) |
0766b2c0 | 507 | return 1; |
7d23383d | 508 | |
75a70cf9 | 509 | switch (gimple_assign_rhs_code (stmt)) |
510 | { | |
7d23383d | 511 | case MULT_EXPR: |
23da77dd | 512 | case WIDEN_MULT_EXPR: |
513 | case WIDEN_MULT_PLUS_EXPR: | |
514 | case WIDEN_MULT_MINUS_EXPR: | |
515 | case DOT_PROD_EXPR: | |
516 | case FMA_EXPR: | |
7d23383d | 517 | case TRUNC_DIV_EXPR: |
518 | case CEIL_DIV_EXPR: | |
519 | case FLOOR_DIV_EXPR: | |
520 | case ROUND_DIV_EXPR: | |
521 | case EXACT_DIV_EXPR: | |
522 | case CEIL_MOD_EXPR: | |
523 | case FLOOR_MOD_EXPR: | |
524 | case ROUND_MOD_EXPR: | |
525 | case TRUNC_MOD_EXPR: | |
fd544fc8 | 526 | case RDIV_EXPR: |
7d23383d | 527 | /* Division and multiplication are usually expensive. */ |
0766b2c0 | 528 | return LIM_EXPENSIVE; |
7d23383d | 529 | |
790963ba | 530 | case LSHIFT_EXPR: |
531 | case RSHIFT_EXPR: | |
23da77dd | 532 | case WIDEN_LSHIFT_EXPR: |
533 | case LROTATE_EXPR: | |
534 | case RROTATE_EXPR: | |
0766b2c0 | 535 | /* Shifts and rotates are usually expensive. */ |
536 | return LIM_EXPENSIVE; | |
537 | ||
538 | case CONSTRUCTOR: | |
539 | /* Make vector construction cost proportional to the number | |
540 | of elements. */ | |
541 | return CONSTRUCTOR_NELTS (gimple_assign_rhs1 (stmt)); | |
542 | ||
543 | case SSA_NAME: | |
544 | case PAREN_EXPR: | |
545 | /* Whether or not something is wrapped inside a PAREN_EXPR | |
546 | should not change move cost. Nor should an intermediate | |
547 | unpropagated SSA name copy. */ | |
548 | return 0; | |
790963ba | 549 | |
7d23383d | 550 | default: |
0766b2c0 | 551 | return 1; |
7d23383d | 552 | } |
7d23383d | 553 | } |
554 | ||
063a8bce | 555 | /* Finds the outermost loop between OUTER and LOOP in that the memory reference |
556 | REF is independent. If REF is not independent in LOOP, NULL is returned | |
557 | instead. */ | |
558 | ||
559 | static struct loop * | |
560 | outermost_indep_loop (struct loop *outer, struct loop *loop, mem_ref_p ref) | |
561 | { | |
562 | struct loop *aloop; | |
563 | ||
3e48928c | 564 | if (ref->stored && bitmap_bit_p (ref->stored, loop->num)) |
063a8bce | 565 | return NULL; |
566 | ||
567 | for (aloop = outer; | |
568 | aloop != loop; | |
569 | aloop = superloop_at_depth (loop, loop_depth (aloop) + 1)) | |
3e48928c | 570 | if ((!ref->stored || !bitmap_bit_p (ref->stored, aloop->num)) |
063a8bce | 571 | && ref_indep_loop_p (aloop, ref)) |
572 | return aloop; | |
573 | ||
574 | if (ref_indep_loop_p (loop, ref)) | |
575 | return loop; | |
576 | else | |
577 | return NULL; | |
578 | } | |
579 | ||
580 | /* If there is a simple load or store to a memory reference in STMT, returns | |
f0b5f617 | 581 | the location of the memory reference, and sets IS_STORE according to whether |
063a8bce | 582 | it is a store or load. Otherwise, returns NULL. */ |
583 | ||
584 | static tree * | |
75a70cf9 | 585 | simple_mem_ref_in_stmt (gimple stmt, bool *is_store) |
063a8bce | 586 | { |
6d7105fe | 587 | tree *lhs, *rhs; |
063a8bce | 588 | |
6d7105fe | 589 | /* Recognize SSA_NAME = MEM and MEM = (SSA_NAME | invariant) patterns. */ |
590 | if (!gimple_assign_single_p (stmt)) | |
063a8bce | 591 | return NULL; |
592 | ||
75a70cf9 | 593 | lhs = gimple_assign_lhs_ptr (stmt); |
6d7105fe | 594 | rhs = gimple_assign_rhs1_ptr (stmt); |
063a8bce | 595 | |
6d7105fe | 596 | if (TREE_CODE (*lhs) == SSA_NAME && gimple_vuse (stmt)) |
063a8bce | 597 | { |
063a8bce | 598 | *is_store = false; |
6d7105fe | 599 | return rhs; |
063a8bce | 600 | } |
6d7105fe | 601 | else if (gimple_vdef (stmt) |
602 | && (TREE_CODE (*rhs) == SSA_NAME || is_gimple_min_invariant (*rhs))) | |
063a8bce | 603 | { |
604 | *is_store = true; | |
605 | return lhs; | |
606 | } | |
607 | else | |
608 | return NULL; | |
609 | } | |
610 | ||
611 | /* Returns the memory reference contained in STMT. */ | |
612 | ||
613 | static mem_ref_p | |
75a70cf9 | 614 | mem_ref_in_stmt (gimple stmt) |
063a8bce | 615 | { |
616 | bool store; | |
617 | tree *mem = simple_mem_ref_in_stmt (stmt, &store); | |
618 | hashval_t hash; | |
619 | mem_ref_p ref; | |
620 | ||
621 | if (!mem) | |
622 | return NULL; | |
623 | gcc_assert (!store); | |
624 | ||
625 | hash = iterative_hash_expr (*mem, 0); | |
c1f445d2 | 626 | ref = memory_accesses.refs->find_with_hash (*mem, hash); |
063a8bce | 627 | |
628 | gcc_assert (ref != NULL); | |
629 | return ref; | |
630 | } | |
631 | ||
9bf0a3f9 | 632 | /* From a controlling predicate in DOM determine the arguments from |
633 | the PHI node PHI that are chosen if the predicate evaluates to | |
634 | true and false and store them to *TRUE_ARG_P and *FALSE_ARG_P if | |
635 | they are non-NULL. Returns true if the arguments can be determined, | |
636 | else return false. */ | |
637 | ||
638 | static bool | |
1a91d914 | 639 | extract_true_false_args_from_phi (basic_block dom, gphi *phi, |
9bf0a3f9 | 640 | tree *true_arg_p, tree *false_arg_p) |
641 | { | |
642 | basic_block bb = gimple_bb (phi); | |
643 | edge true_edge, false_edge, tem; | |
644 | tree arg0 = NULL_TREE, arg1 = NULL_TREE; | |
645 | ||
646 | /* We have to verify that one edge into the PHI node is dominated | |
647 | by the true edge of the predicate block and the other edge | |
648 | dominated by the false edge. This ensures that the PHI argument | |
649 | we are going to take is completely determined by the path we | |
b533d4c1 | 650 | take from the predicate block. |
651 | We can only use BB dominance checks below if the destination of | |
652 | the true/false edges are dominated by their edge, thus only | |
653 | have a single predecessor. */ | |
9bf0a3f9 | 654 | extract_true_false_edges_from_block (dom, &true_edge, &false_edge); |
655 | tem = EDGE_PRED (bb, 0); | |
656 | if (tem == true_edge | |
b533d4c1 | 657 | || (single_pred_p (true_edge->dest) |
658 | && (tem->src == true_edge->dest | |
659 | || dominated_by_p (CDI_DOMINATORS, | |
660 | tem->src, true_edge->dest)))) | |
9bf0a3f9 | 661 | arg0 = PHI_ARG_DEF (phi, tem->dest_idx); |
662 | else if (tem == false_edge | |
b533d4c1 | 663 | || (single_pred_p (false_edge->dest) |
664 | && (tem->src == false_edge->dest | |
665 | || dominated_by_p (CDI_DOMINATORS, | |
666 | tem->src, false_edge->dest)))) | |
9bf0a3f9 | 667 | arg1 = PHI_ARG_DEF (phi, tem->dest_idx); |
668 | else | |
669 | return false; | |
670 | tem = EDGE_PRED (bb, 1); | |
671 | if (tem == true_edge | |
b533d4c1 | 672 | || (single_pred_p (true_edge->dest) |
673 | && (tem->src == true_edge->dest | |
674 | || dominated_by_p (CDI_DOMINATORS, | |
675 | tem->src, true_edge->dest)))) | |
9bf0a3f9 | 676 | arg0 = PHI_ARG_DEF (phi, tem->dest_idx); |
677 | else if (tem == false_edge | |
b533d4c1 | 678 | || (single_pred_p (false_edge->dest) |
679 | && (tem->src == false_edge->dest | |
680 | || dominated_by_p (CDI_DOMINATORS, | |
681 | tem->src, false_edge->dest)))) | |
9bf0a3f9 | 682 | arg1 = PHI_ARG_DEF (phi, tem->dest_idx); |
683 | else | |
684 | return false; | |
685 | if (!arg0 || !arg1) | |
686 | return false; | |
687 | ||
688 | if (true_arg_p) | |
689 | *true_arg_p = arg0; | |
690 | if (false_arg_p) | |
691 | *false_arg_p = arg1; | |
692 | ||
693 | return true; | |
694 | } | |
695 | ||
7d23383d | 696 | /* Determine the outermost loop to that it is possible to hoist a statement |
697 | STMT and store it to LIM_DATA (STMT)->max_loop. To do this we determine | |
698 | the outermost loop in that the value computed by STMT is invariant. | |
699 | If MUST_PRESERVE_EXEC is true, additionally choose such a loop that | |
700 | we preserve the fact whether STMT is executed. It also fills other related | |
701 | information to LIM_DATA (STMT). | |
48e1416a | 702 | |
7d23383d | 703 | The function returns false if STMT cannot be hoisted outside of the loop it |
704 | is defined in, and true otherwise. */ | |
705 | ||
706 | static bool | |
75a70cf9 | 707 | determine_max_movement (gimple stmt, bool must_preserve_exec) |
7d23383d | 708 | { |
75a70cf9 | 709 | basic_block bb = gimple_bb (stmt); |
7d23383d | 710 | struct loop *loop = bb->loop_father; |
711 | struct loop *level; | |
75a70cf9 | 712 | struct lim_aux_data *lim_data = get_lim_data (stmt); |
43daa21e | 713 | tree val; |
714 | ssa_op_iter iter; | |
48e1416a | 715 | |
7d23383d | 716 | if (must_preserve_exec) |
717 | level = ALWAYS_EXECUTED_IN (bb); | |
718 | else | |
719 | level = superloop_at_depth (loop, 1); | |
720 | lim_data->max_loop = level; | |
721 | ||
1a91d914 | 722 | if (gphi *phi = dyn_cast <gphi *> (stmt)) |
9bf0a3f9 | 723 | { |
724 | use_operand_p use_p; | |
725 | unsigned min_cost = UINT_MAX; | |
726 | unsigned total_cost = 0; | |
727 | struct lim_aux_data *def_data; | |
728 | ||
729 | /* We will end up promoting dependencies to be unconditionally | |
730 | evaluated. For this reason the PHI cost (and thus the | |
731 | cost we remove from the loop by doing the invariant motion) | |
732 | is that of the cheapest PHI argument dependency chain. */ | |
1a91d914 | 733 | FOR_EACH_PHI_ARG (use_p, phi, iter, SSA_OP_USE) |
9bf0a3f9 | 734 | { |
735 | val = USE_FROM_PTR (use_p); | |
413fb820 | 736 | |
9bf0a3f9 | 737 | if (TREE_CODE (val) != SSA_NAME) |
413fb820 | 738 | { |
739 | /* Assign const 1 to constants. */ | |
740 | min_cost = MIN (min_cost, 1); | |
741 | total_cost += 1; | |
742 | continue; | |
743 | } | |
9bf0a3f9 | 744 | if (!add_dependency (val, lim_data, loop, false)) |
745 | return false; | |
07f7799f | 746 | |
747 | gimple def_stmt = SSA_NAME_DEF_STMT (val); | |
748 | if (gimple_bb (def_stmt) | |
749 | && gimple_bb (def_stmt)->loop_father == loop) | |
9bf0a3f9 | 750 | { |
07f7799f | 751 | def_data = get_lim_data (def_stmt); |
752 | if (def_data) | |
753 | { | |
754 | min_cost = MIN (min_cost, def_data->cost); | |
755 | total_cost += def_data->cost; | |
756 | } | |
9bf0a3f9 | 757 | } |
758 | } | |
759 | ||
07f7799f | 760 | min_cost = MIN (min_cost, total_cost); |
9bf0a3f9 | 761 | lim_data->cost += min_cost; |
762 | ||
1a91d914 | 763 | if (gimple_phi_num_args (phi) > 1) |
9bf0a3f9 | 764 | { |
765 | basic_block dom = get_immediate_dominator (CDI_DOMINATORS, bb); | |
766 | gimple cond; | |
767 | if (gsi_end_p (gsi_last_bb (dom))) | |
768 | return false; | |
769 | cond = gsi_stmt (gsi_last_bb (dom)); | |
770 | if (gimple_code (cond) != GIMPLE_COND) | |
771 | return false; | |
772 | /* Verify that this is an extended form of a diamond and | |
773 | the PHI arguments are completely controlled by the | |
774 | predicate in DOM. */ | |
1a91d914 | 775 | if (!extract_true_false_args_from_phi (dom, phi, NULL, NULL)) |
9bf0a3f9 | 776 | return false; |
777 | ||
778 | /* Fold in dependencies and cost of the condition. */ | |
779 | FOR_EACH_SSA_TREE_OPERAND (val, cond, iter, SSA_OP_USE) | |
780 | { | |
781 | if (!add_dependency (val, lim_data, loop, false)) | |
782 | return false; | |
783 | def_data = get_lim_data (SSA_NAME_DEF_STMT (val)); | |
784 | if (def_data) | |
785 | total_cost += def_data->cost; | |
786 | } | |
787 | ||
788 | /* We want to avoid unconditionally executing very expensive | |
789 | operations. As costs for our dependencies cannot be | |
790 | negative just claim we are not invariand for this case. | |
791 | We also are not sure whether the control-flow inside the | |
792 | loop will vanish. */ | |
793 | if (total_cost - min_cost >= 2 * LIM_EXPENSIVE | |
794 | && !(min_cost != 0 | |
795 | && total_cost / min_cost <= 2)) | |
796 | return false; | |
797 | ||
798 | /* Assume that the control-flow in the loop will vanish. | |
799 | ??? We should verify this and not artificially increase | |
800 | the cost if that is not the case. */ | |
801 | lim_data->cost += stmt_cost (stmt); | |
802 | } | |
803 | ||
804 | return true; | |
805 | } | |
806 | else | |
807 | FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_USE) | |
808 | if (!add_dependency (val, lim_data, loop, true)) | |
809 | return false; | |
7d23383d | 810 | |
dd277d48 | 811 | if (gimple_vuse (stmt)) |
063a8bce | 812 | { |
813 | mem_ref_p ref = mem_ref_in_stmt (stmt); | |
814 | ||
815 | if (ref) | |
816 | { | |
817 | lim_data->max_loop | |
818 | = outermost_indep_loop (lim_data->max_loop, loop, ref); | |
819 | if (!lim_data->max_loop) | |
820 | return false; | |
821 | } | |
822 | else | |
823 | { | |
dd277d48 | 824 | if ((val = gimple_vuse (stmt)) != NULL_TREE) |
063a8bce | 825 | { |
826 | if (!add_dependency (val, lim_data, loop, false)) | |
827 | return false; | |
828 | } | |
829 | } | |
830 | } | |
7d23383d | 831 | |
832 | lim_data->cost += stmt_cost (stmt); | |
833 | ||
834 | return true; | |
835 | } | |
836 | ||
837 | /* Suppose that some statement in ORIG_LOOP is hoisted to the loop LEVEL, | |
838 | and that one of the operands of this statement is computed by STMT. | |
839 | Ensure that STMT (together with all the statements that define its | |
840 | operands) is hoisted at least out of the loop LEVEL. */ | |
841 | ||
842 | static void | |
75a70cf9 | 843 | set_level (gimple stmt, struct loop *orig_loop, struct loop *level) |
7d23383d | 844 | { |
75a70cf9 | 845 | struct loop *stmt_loop = gimple_bb (stmt)->loop_father; |
75a70cf9 | 846 | struct lim_aux_data *lim_data; |
a2c22c0d | 847 | gimple dep_stmt; |
848 | unsigned i; | |
7d23383d | 849 | |
850 | stmt_loop = find_common_loop (orig_loop, stmt_loop); | |
75a70cf9 | 851 | lim_data = get_lim_data (stmt); |
852 | if (lim_data != NULL && lim_data->tgt_loop != NULL) | |
7d23383d | 853 | stmt_loop = find_common_loop (stmt_loop, |
75a70cf9 | 854 | loop_outer (lim_data->tgt_loop)); |
7d23383d | 855 | if (flow_loop_nested_p (stmt_loop, level)) |
856 | return; | |
857 | ||
75a70cf9 | 858 | gcc_assert (level == lim_data->max_loop |
859 | || flow_loop_nested_p (lim_data->max_loop, level)); | |
7d23383d | 860 | |
75a70cf9 | 861 | lim_data->tgt_loop = level; |
a2c22c0d | 862 | FOR_EACH_VEC_ELT (lim_data->depends, i, dep_stmt) |
863 | set_level (dep_stmt, orig_loop, level); | |
7d23383d | 864 | } |
865 | ||
866 | /* Determines an outermost loop from that we want to hoist the statement STMT. | |
867 | For now we chose the outermost possible loop. TODO -- use profiling | |
868 | information to set it more sanely. */ | |
869 | ||
870 | static void | |
75a70cf9 | 871 | set_profitable_level (gimple stmt) |
7d23383d | 872 | { |
75a70cf9 | 873 | set_level (stmt, gimple_bb (stmt)->loop_father, get_lim_data (stmt)->max_loop); |
7d23383d | 874 | } |
875 | ||
75a70cf9 | 876 | /* Returns true if STMT is a call that has side effects. */ |
7d23383d | 877 | |
878 | static bool | |
75a70cf9 | 879 | nonpure_call_p (gimple stmt) |
7d23383d | 880 | { |
75a70cf9 | 881 | if (gimple_code (stmt) != GIMPLE_CALL) |
7d23383d | 882 | return false; |
883 | ||
75a70cf9 | 884 | return gimple_has_side_effects (stmt); |
7d23383d | 885 | } |
886 | ||
790963ba | 887 | /* Rewrite a/b to a*(1/b). Return the invariant stmt to process. */ |
888 | ||
75a70cf9 | 889 | static gimple |
890 | rewrite_reciprocal (gimple_stmt_iterator *bsi) | |
790963ba | 891 | { |
1a91d914 | 892 | gassign *stmt, *stmt1, *stmt2; |
03d37e4e | 893 | tree name, lhs, type; |
193b8a15 | 894 | tree real_one; |
688ff29b | 895 | gimple_stmt_iterator gsi; |
790963ba | 896 | |
1a91d914 | 897 | stmt = as_a <gassign *> (gsi_stmt (*bsi)); |
75a70cf9 | 898 | lhs = gimple_assign_lhs (stmt); |
899 | type = TREE_TYPE (lhs); | |
790963ba | 900 | |
74560f89 | 901 | real_one = build_one_cst (type); |
790963ba | 902 | |
03d37e4e | 903 | name = make_temp_ssa_name (type, NULL, "reciptmp"); |
e9cf809e | 904 | stmt1 = gimple_build_assign (name, RDIV_EXPR, real_one, |
905 | gimple_assign_rhs2 (stmt)); | |
906 | stmt2 = gimple_build_assign (lhs, MULT_EXPR, name, | |
907 | gimple_assign_rhs1 (stmt)); | |
790963ba | 908 | |
909 | /* Replace division stmt with reciprocal and multiply stmts. | |
910 | The multiply stmt is not invariant, so update iterator | |
911 | and avoid rescanning. */ | |
688ff29b | 912 | gsi = *bsi; |
913 | gsi_insert_before (bsi, stmt1, GSI_NEW_STMT); | |
914 | gsi_replace (&gsi, stmt2, true); | |
790963ba | 915 | |
916 | /* Continue processing with invariant reciprocal statement. */ | |
917 | return stmt1; | |
918 | } | |
919 | ||
920 | /* Check if the pattern at *BSI is a bittest of the form | |
921 | (A >> B) & 1 != 0 and in this case rewrite it to A & (1 << B) != 0. */ | |
922 | ||
75a70cf9 | 923 | static gimple |
924 | rewrite_bittest (gimple_stmt_iterator *bsi) | |
790963ba | 925 | { |
1a91d914 | 926 | gassign *stmt; |
927 | gimple stmt1; | |
928 | gassign *stmt2; | |
929 | gimple use_stmt; | |
930 | gcond *cond_stmt; | |
03d37e4e | 931 | tree lhs, name, t, a, b; |
790963ba | 932 | use_operand_p use; |
933 | ||
1a91d914 | 934 | stmt = as_a <gassign *> (gsi_stmt (*bsi)); |
75a70cf9 | 935 | lhs = gimple_assign_lhs (stmt); |
790963ba | 936 | |
937 | /* Verify that the single use of lhs is a comparison against zero. */ | |
938 | if (TREE_CODE (lhs) != SSA_NAME | |
1a91d914 | 939 | || !single_imm_use (lhs, &use, &use_stmt)) |
790963ba | 940 | return stmt; |
1a91d914 | 941 | cond_stmt = dyn_cast <gcond *> (use_stmt); |
942 | if (!cond_stmt) | |
943 | return stmt; | |
944 | if (gimple_cond_lhs (cond_stmt) != lhs | |
945 | || (gimple_cond_code (cond_stmt) != NE_EXPR | |
946 | && gimple_cond_code (cond_stmt) != EQ_EXPR) | |
947 | || !integer_zerop (gimple_cond_rhs (cond_stmt))) | |
790963ba | 948 | return stmt; |
949 | ||
950 | /* Get at the operands of the shift. The rhs is TMP1 & 1. */ | |
75a70cf9 | 951 | stmt1 = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (stmt)); |
952 | if (gimple_code (stmt1) != GIMPLE_ASSIGN) | |
790963ba | 953 | return stmt; |
954 | ||
bef304b8 | 955 | /* There is a conversion in between possibly inserted by fold. */ |
d9659041 | 956 | if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt1))) |
790963ba | 957 | { |
75a70cf9 | 958 | t = gimple_assign_rhs1 (stmt1); |
790963ba | 959 | if (TREE_CODE (t) != SSA_NAME |
960 | || !has_single_use (t)) | |
961 | return stmt; | |
962 | stmt1 = SSA_NAME_DEF_STMT (t); | |
75a70cf9 | 963 | if (gimple_code (stmt1) != GIMPLE_ASSIGN) |
790963ba | 964 | return stmt; |
790963ba | 965 | } |
966 | ||
967 | /* Verify that B is loop invariant but A is not. Verify that with | |
968 | all the stmt walking we are still in the same loop. */ | |
75a70cf9 | 969 | if (gimple_assign_rhs_code (stmt1) != RSHIFT_EXPR |
970 | || loop_containing_stmt (stmt1) != loop_containing_stmt (stmt)) | |
971 | return stmt; | |
790963ba | 972 | |
75a70cf9 | 973 | a = gimple_assign_rhs1 (stmt1); |
974 | b = gimple_assign_rhs2 (stmt1); | |
975 | ||
976 | if (outermost_invariant_loop (b, loop_containing_stmt (stmt1)) != NULL | |
977 | && outermost_invariant_loop (a, loop_containing_stmt (stmt1)) == NULL) | |
978 | { | |
688ff29b | 979 | gimple_stmt_iterator rsi; |
980 | ||
790963ba | 981 | /* 1 << B */ |
790963ba | 982 | t = fold_build2 (LSHIFT_EXPR, TREE_TYPE (a), |
983 | build_int_cst (TREE_TYPE (a), 1), b); | |
03d37e4e | 984 | name = make_temp_ssa_name (TREE_TYPE (a), NULL, "shifttmp"); |
985 | stmt1 = gimple_build_assign (name, t); | |
790963ba | 986 | |
987 | /* A & (1 << B) */ | |
988 | t = fold_build2 (BIT_AND_EXPR, TREE_TYPE (a), a, name); | |
03d37e4e | 989 | name = make_temp_ssa_name (TREE_TYPE (a), NULL, "shifttmp"); |
990 | stmt2 = gimple_build_assign (name, t); | |
3de988b5 | 991 | |
992 | /* Replace the SSA_NAME we compare against zero. Adjust | |
993 | the type of zero accordingly. */ | |
27dc0bdf | 994 | SET_USE (use, name); |
1a91d914 | 995 | gimple_cond_set_rhs (cond_stmt, |
996 | build_int_cst_type (TREE_TYPE (name), | |
997 | 0)); | |
790963ba | 998 | |
688ff29b | 999 | /* Don't use gsi_replace here, none of the new assignments sets |
1000 | the variable originally set in stmt. Move bsi to stmt1, and | |
1001 | then remove the original stmt, so that we get a chance to | |
1002 | retain debug info for it. */ | |
1003 | rsi = *bsi; | |
1004 | gsi_insert_before (bsi, stmt1, GSI_NEW_STMT); | |
1005 | gsi_insert_before (&rsi, stmt2, GSI_SAME_STMT); | |
1006 | gsi_remove (&rsi, true); | |
790963ba | 1007 | |
1008 | return stmt1; | |
1009 | } | |
1010 | ||
1011 | return stmt; | |
1012 | } | |
1013 | ||
54c91640 | 1014 | /* For each statement determines the outermost loop in that it is invariant, |
1015 | - statements on whose motion it depends and the cost of the computation. | |
1016 | - This information is stored to the LIM_DATA structure associated with | |
1017 | - each statement. */ | |
1018 | class invariantness_dom_walker : public dom_walker | |
1019 | { | |
1020 | public: | |
1021 | invariantness_dom_walker (cdi_direction direction) | |
1022 | : dom_walker (direction) {} | |
1023 | ||
1024 | virtual void before_dom_children (basic_block); | |
1025 | }; | |
790963ba | 1026 | |
7d23383d | 1027 | /* Determine the outermost loops in that statements in basic block BB are |
1028 | invariant, and record them to the LIM_DATA associated with the statements. | |
54c91640 | 1029 | Callback for dom_walker. */ |
7d23383d | 1030 | |
54c91640 | 1031 | void |
1032 | invariantness_dom_walker::before_dom_children (basic_block bb) | |
7d23383d | 1033 | { |
1034 | enum move_pos pos; | |
75a70cf9 | 1035 | gimple_stmt_iterator bsi; |
1036 | gimple stmt; | |
7d23383d | 1037 | bool maybe_never = ALWAYS_EXECUTED_IN (bb) == NULL; |
1038 | struct loop *outermost = ALWAYS_EXECUTED_IN (bb); | |
75a70cf9 | 1039 | struct lim_aux_data *lim_data; |
7d23383d | 1040 | |
9e3536f4 | 1041 | if (!loop_outer (bb->loop_father)) |
7d23383d | 1042 | return; |
1043 | ||
1044 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1045 | fprintf (dump_file, "Basic block %d (loop %d -- depth %d):\n\n", | |
9e3536f4 | 1046 | bb->index, bb->loop_father->num, loop_depth (bb->loop_father)); |
7d23383d | 1047 | |
9bf0a3f9 | 1048 | /* Look at PHI nodes, but only if there is at most two. |
1049 | ??? We could relax this further by post-processing the inserted | |
1050 | code and transforming adjacent cond-exprs with the same predicate | |
1051 | to control flow again. */ | |
1052 | bsi = gsi_start_phis (bb); | |
1053 | if (!gsi_end_p (bsi) | |
1054 | && ((gsi_next (&bsi), gsi_end_p (bsi)) | |
1055 | || (gsi_next (&bsi), gsi_end_p (bsi)))) | |
1056 | for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
1057 | { | |
1058 | stmt = gsi_stmt (bsi); | |
1059 | ||
1060 | pos = movement_possibility (stmt); | |
1061 | if (pos == MOVE_IMPOSSIBLE) | |
1062 | continue; | |
1063 | ||
1064 | lim_data = init_lim_data (stmt); | |
1065 | lim_data->always_executed_in = outermost; | |
1066 | ||
1067 | if (!determine_max_movement (stmt, false)) | |
1068 | { | |
1069 | lim_data->max_loop = NULL; | |
1070 | continue; | |
1071 | } | |
1072 | ||
1073 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1074 | { | |
1075 | print_gimple_stmt (dump_file, stmt, 2, 0); | |
1076 | fprintf (dump_file, " invariant up to level %d, cost %d.\n\n", | |
1077 | loop_depth (lim_data->max_loop), | |
1078 | lim_data->cost); | |
1079 | } | |
1080 | ||
1081 | if (lim_data->cost >= LIM_EXPENSIVE) | |
1082 | set_profitable_level (stmt); | |
1083 | } | |
1084 | ||
75a70cf9 | 1085 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
7d23383d | 1086 | { |
75a70cf9 | 1087 | stmt = gsi_stmt (bsi); |
7d23383d | 1088 | |
1089 | pos = movement_possibility (stmt); | |
1090 | if (pos == MOVE_IMPOSSIBLE) | |
1091 | { | |
1092 | if (nonpure_call_p (stmt)) | |
1093 | { | |
1094 | maybe_never = true; | |
1095 | outermost = NULL; | |
1096 | } | |
a973ed42 | 1097 | /* Make sure to note always_executed_in for stores to make |
1098 | store-motion work. */ | |
1099 | else if (stmt_makes_single_store (stmt)) | |
1100 | { | |
75a70cf9 | 1101 | struct lim_aux_data *lim_data = init_lim_data (stmt); |
1102 | lim_data->always_executed_in = outermost; | |
a973ed42 | 1103 | } |
7d23383d | 1104 | continue; |
1105 | } | |
1106 | ||
75a70cf9 | 1107 | if (is_gimple_assign (stmt) |
1108 | && (get_gimple_rhs_class (gimple_assign_rhs_code (stmt)) | |
1109 | == GIMPLE_BINARY_RHS)) | |
63f88450 | 1110 | { |
75a70cf9 | 1111 | tree op0 = gimple_assign_rhs1 (stmt); |
1112 | tree op1 = gimple_assign_rhs2 (stmt); | |
1113 | struct loop *ol1 = outermost_invariant_loop (op1, | |
1114 | loop_containing_stmt (stmt)); | |
63f88450 | 1115 | |
1116 | /* If divisor is invariant, convert a/b to a*(1/b), allowing reciprocal | |
1117 | to be hoisted out of loop, saving expensive divide. */ | |
1118 | if (pos == MOVE_POSSIBLE | |
75a70cf9 | 1119 | && gimple_assign_rhs_code (stmt) == RDIV_EXPR |
63f88450 | 1120 | && flag_unsafe_math_optimizations |
1121 | && !flag_trapping_math | |
75a70cf9 | 1122 | && ol1 != NULL |
1123 | && outermost_invariant_loop (op0, ol1) == NULL) | |
63f88450 | 1124 | stmt = rewrite_reciprocal (&bsi); |
1125 | ||
1126 | /* If the shift count is invariant, convert (A >> B) & 1 to | |
1127 | A & (1 << B) allowing the bit mask to be hoisted out of the loop | |
1128 | saving an expensive shift. */ | |
1129 | if (pos == MOVE_POSSIBLE | |
75a70cf9 | 1130 | && gimple_assign_rhs_code (stmt) == BIT_AND_EXPR |
1131 | && integer_onep (op1) | |
1132 | && TREE_CODE (op0) == SSA_NAME | |
1133 | && has_single_use (op0)) | |
63f88450 | 1134 | stmt = rewrite_bittest (&bsi); |
1135 | } | |
fcee97ca | 1136 | |
75a70cf9 | 1137 | lim_data = init_lim_data (stmt); |
1138 | lim_data->always_executed_in = outermost; | |
7d23383d | 1139 | |
1140 | if (maybe_never && pos == MOVE_PRESERVE_EXECUTION) | |
1141 | continue; | |
1142 | ||
1143 | if (!determine_max_movement (stmt, pos == MOVE_PRESERVE_EXECUTION)) | |
1144 | { | |
75a70cf9 | 1145 | lim_data->max_loop = NULL; |
7d23383d | 1146 | continue; |
1147 | } | |
1148 | ||
1149 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1150 | { | |
75a70cf9 | 1151 | print_gimple_stmt (dump_file, stmt, 2, 0); |
7d23383d | 1152 | fprintf (dump_file, " invariant up to level %d, cost %d.\n\n", |
75a70cf9 | 1153 | loop_depth (lim_data->max_loop), |
1154 | lim_data->cost); | |
7d23383d | 1155 | } |
1156 | ||
75a70cf9 | 1157 | if (lim_data->cost >= LIM_EXPENSIVE) |
7d23383d | 1158 | set_profitable_level (stmt); |
1159 | } | |
1160 | } | |
1161 | ||
54c91640 | 1162 | class move_computations_dom_walker : public dom_walker |
7d23383d | 1163 | { |
54c91640 | 1164 | public: |
1165 | move_computations_dom_walker (cdi_direction direction) | |
1166 | : dom_walker (direction), todo_ (0) {} | |
7d23383d | 1167 | |
54c91640 | 1168 | virtual void before_dom_children (basic_block); |
7d23383d | 1169 | |
54c91640 | 1170 | unsigned int todo_; |
1171 | }; | |
7d23383d | 1172 | |
7d23383d | 1173 | /* Hoist the statements in basic block BB out of the loops prescribed by |
91275768 | 1174 | data stored in LIM_DATA structures associated with each statement. Callback |
7d23383d | 1175 | for walk_dominator_tree. */ |
1176 | ||
54c91640 | 1177 | void |
1178 | move_computations_dom_walker::before_dom_children (basic_block bb) | |
7d23383d | 1179 | { |
1180 | struct loop *level; | |
7d23383d | 1181 | unsigned cost = 0; |
75a70cf9 | 1182 | struct lim_aux_data *lim_data; |
7d23383d | 1183 | |
9e3536f4 | 1184 | if (!loop_outer (bb->loop_father)) |
7d23383d | 1185 | return; |
1186 | ||
1a91d914 | 1187 | for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); ) |
9bf0a3f9 | 1188 | { |
1a91d914 | 1189 | gassign *new_stmt; |
1190 | gphi *stmt = bsi.phi (); | |
9bf0a3f9 | 1191 | |
1192 | lim_data = get_lim_data (stmt); | |
1193 | if (lim_data == NULL) | |
1194 | { | |
1195 | gsi_next (&bsi); | |
1196 | continue; | |
1197 | } | |
1198 | ||
1199 | cost = lim_data->cost; | |
1200 | level = lim_data->tgt_loop; | |
1201 | clear_lim_data (stmt); | |
1202 | ||
1203 | if (!level) | |
1204 | { | |
1205 | gsi_next (&bsi); | |
1206 | continue; | |
1207 | } | |
1208 | ||
1209 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1210 | { | |
1211 | fprintf (dump_file, "Moving PHI node\n"); | |
1212 | print_gimple_stmt (dump_file, stmt, 0, 0); | |
1213 | fprintf (dump_file, "(cost %u) out of loop %d.\n\n", | |
1214 | cost, level->num); | |
1215 | } | |
1216 | ||
1217 | if (gimple_phi_num_args (stmt) == 1) | |
1218 | { | |
1219 | tree arg = PHI_ARG_DEF (stmt, 0); | |
e9cf809e | 1220 | new_stmt = gimple_build_assign (gimple_phi_result (stmt), |
1221 | TREE_CODE (arg), arg); | |
9bf0a3f9 | 1222 | } |
1223 | else | |
1224 | { | |
1225 | basic_block dom = get_immediate_dominator (CDI_DOMINATORS, bb); | |
1226 | gimple cond = gsi_stmt (gsi_last_bb (dom)); | |
1227 | tree arg0 = NULL_TREE, arg1 = NULL_TREE, t; | |
1228 | /* Get the PHI arguments corresponding to the true and false | |
1229 | edges of COND. */ | |
1230 | extract_true_false_args_from_phi (dom, stmt, &arg0, &arg1); | |
1231 | gcc_assert (arg0 && arg1); | |
1232 | t = build2 (gimple_cond_code (cond), boolean_type_node, | |
1233 | gimple_cond_lhs (cond), gimple_cond_rhs (cond)); | |
e9cf809e | 1234 | new_stmt = gimple_build_assign (gimple_phi_result (stmt), |
1235 | COND_EXPR, t, arg0, arg1); | |
54c91640 | 1236 | todo_ |= TODO_cleanup_cfg; |
9bf0a3f9 | 1237 | } |
8e50a020 | 1238 | if (INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (new_stmt))) |
1239 | && (!ALWAYS_EXECUTED_IN (bb) | |
1240 | || (ALWAYS_EXECUTED_IN (bb) != level | |
1241 | && !flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
ccf6cffa | 1242 | { |
1243 | tree lhs = gimple_assign_lhs (new_stmt); | |
1244 | SSA_NAME_RANGE_INFO (lhs) = NULL; | |
1245 | SSA_NAME_ANTI_RANGE_P (lhs) = 0; | |
1246 | } | |
9bf0a3f9 | 1247 | gsi_insert_on_edge (loop_preheader_edge (level), new_stmt); |
1248 | remove_phi_node (&bsi, false); | |
1249 | } | |
1250 | ||
1a91d914 | 1251 | for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); ) |
7d23383d | 1252 | { |
e70e8b13 | 1253 | edge e; |
1254 | ||
1a91d914 | 1255 | gimple stmt = gsi_stmt (bsi); |
7d23383d | 1256 | |
75a70cf9 | 1257 | lim_data = get_lim_data (stmt); |
1258 | if (lim_data == NULL) | |
7d23383d | 1259 | { |
75a70cf9 | 1260 | gsi_next (&bsi); |
7d23383d | 1261 | continue; |
1262 | } | |
1263 | ||
75a70cf9 | 1264 | cost = lim_data->cost; |
1265 | level = lim_data->tgt_loop; | |
1266 | clear_lim_data (stmt); | |
7d23383d | 1267 | |
1268 | if (!level) | |
1269 | { | |
75a70cf9 | 1270 | gsi_next (&bsi); |
7d23383d | 1271 | continue; |
1272 | } | |
1273 | ||
1274 | /* We do not really want to move conditionals out of the loop; we just | |
1275 | placed it here to force its operands to be moved if necessary. */ | |
75a70cf9 | 1276 | if (gimple_code (stmt) == GIMPLE_COND) |
7d23383d | 1277 | continue; |
1278 | ||
1279 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1280 | { | |
1281 | fprintf (dump_file, "Moving statement\n"); | |
75a70cf9 | 1282 | print_gimple_stmt (dump_file, stmt, 0, 0); |
7d23383d | 1283 | fprintf (dump_file, "(cost %u) out of loop %d.\n\n", |
1284 | cost, level->num); | |
1285 | } | |
063a8bce | 1286 | |
e70e8b13 | 1287 | e = loop_preheader_edge (level); |
1288 | gcc_assert (!gimple_vdef (stmt)); | |
1289 | if (gimple_vuse (stmt)) | |
1290 | { | |
1291 | /* The new VUSE is the one from the virtual PHI in the loop | |
1292 | header or the one already present. */ | |
1a91d914 | 1293 | gphi_iterator gsi2; |
e70e8b13 | 1294 | for (gsi2 = gsi_start_phis (e->dest); |
1295 | !gsi_end_p (gsi2); gsi_next (&gsi2)) | |
1296 | { | |
1a91d914 | 1297 | gphi *phi = gsi2.phi (); |
7c782c9b | 1298 | if (virtual_operand_p (gimple_phi_result (phi))) |
e70e8b13 | 1299 | { |
1300 | gimple_set_vuse (stmt, PHI_ARG_DEF_FROM_EDGE (phi, e)); | |
1301 | break; | |
1302 | } | |
1303 | } | |
1304 | } | |
75a70cf9 | 1305 | gsi_remove (&bsi, false); |
8e50a020 | 1306 | if (gimple_has_lhs (stmt) |
1307 | && TREE_CODE (gimple_get_lhs (stmt)) == SSA_NAME | |
1308 | && INTEGRAL_TYPE_P (TREE_TYPE (gimple_get_lhs (stmt))) | |
1309 | && (!ALWAYS_EXECUTED_IN (bb) | |
1310 | || !(ALWAYS_EXECUTED_IN (bb) == level | |
1311 | || flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
ccf6cffa | 1312 | { |
1313 | tree lhs = gimple_get_lhs (stmt); | |
1314 | SSA_NAME_RANGE_INFO (lhs) = NULL; | |
1315 | SSA_NAME_ANTI_RANGE_P (lhs) = 0; | |
1316 | } | |
bc228ba1 | 1317 | /* In case this is a stmt that is not unconditionally executed |
1318 | when the target loop header is executed and the stmt may | |
1319 | invoke undefined integer or pointer overflow rewrite it to | |
1320 | unsigned arithmetic. */ | |
1321 | if (is_gimple_assign (stmt) | |
1322 | && INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (stmt))) | |
1323 | && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (gimple_assign_lhs (stmt))) | |
1324 | && arith_code_with_undefined_signed_overflow | |
1325 | (gimple_assign_rhs_code (stmt)) | |
1326 | && (!ALWAYS_EXECUTED_IN (bb) | |
1327 | || !(ALWAYS_EXECUTED_IN (bb) == level | |
1328 | || flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
1329 | gsi_insert_seq_on_edge (e, rewrite_to_defined_overflow (stmt)); | |
1330 | else | |
1331 | gsi_insert_on_edge (e, stmt); | |
7d23383d | 1332 | } |
1333 | } | |
1334 | ||
1335 | /* Hoist the statements out of the loops prescribed by data stored in | |
91275768 | 1336 | LIM_DATA structures associated with each statement.*/ |
7d23383d | 1337 | |
9bf0a3f9 | 1338 | static unsigned int |
7d23383d | 1339 | move_computations (void) |
1340 | { | |
54c91640 | 1341 | move_computations_dom_walker walker (CDI_DOMINATORS); |
1342 | walker.walk (cfun->cfg->x_entry_block_ptr); | |
7d23383d | 1343 | |
75a70cf9 | 1344 | gsi_commit_edge_inserts (); |
dd277d48 | 1345 | if (need_ssa_update_p (cfun)) |
095dcfa3 | 1346 | rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); |
9bf0a3f9 | 1347 | |
54c91640 | 1348 | return walker.todo_; |
7d23383d | 1349 | } |
1350 | ||
1351 | /* Checks whether the statement defining variable *INDEX can be hoisted | |
1352 | out of the loop passed in DATA. Callback for for_each_index. */ | |
1353 | ||
1354 | static bool | |
1355 | may_move_till (tree ref, tree *index, void *data) | |
1356 | { | |
75a70cf9 | 1357 | struct loop *loop = (struct loop *) data, *max_loop; |
7d23383d | 1358 | |
1359 | /* If REF is an array reference, check also that the step and the lower | |
1360 | bound is invariant in LOOP. */ | |
1361 | if (TREE_CODE (ref) == ARRAY_REF) | |
1362 | { | |
75a70cf9 | 1363 | tree step = TREE_OPERAND (ref, 3); |
1364 | tree lbound = TREE_OPERAND (ref, 2); | |
7d23383d | 1365 | |
75a70cf9 | 1366 | max_loop = outermost_invariant_loop (step, loop); |
7d23383d | 1367 | if (!max_loop) |
1368 | return false; | |
1369 | ||
75a70cf9 | 1370 | max_loop = outermost_invariant_loop (lbound, loop); |
7d23383d | 1371 | if (!max_loop) |
1372 | return false; | |
1373 | } | |
1374 | ||
1375 | max_loop = outermost_invariant_loop (*index, loop); | |
1376 | if (!max_loop) | |
1377 | return false; | |
1378 | ||
1379 | return true; | |
1380 | } | |
1381 | ||
75a70cf9 | 1382 | /* If OP is SSA NAME, force the statement that defines it to be |
99e96094 | 1383 | moved out of the LOOP. ORIG_LOOP is the loop in that EXPR is used. */ |
7d23383d | 1384 | |
1385 | static void | |
75a70cf9 | 1386 | force_move_till_op (tree op, struct loop *orig_loop, struct loop *loop) |
7d23383d | 1387 | { |
75a70cf9 | 1388 | gimple stmt; |
7d23383d | 1389 | |
75a70cf9 | 1390 | if (!op |
1391 | || is_gimple_min_invariant (op)) | |
1392 | return; | |
7d23383d | 1393 | |
75a70cf9 | 1394 | gcc_assert (TREE_CODE (op) == SSA_NAME); |
48e1416a | 1395 | |
75a70cf9 | 1396 | stmt = SSA_NAME_DEF_STMT (op); |
1397 | if (gimple_nop_p (stmt)) | |
7d23383d | 1398 | return; |
1399 | ||
75a70cf9 | 1400 | set_level (stmt, orig_loop, loop); |
7d23383d | 1401 | } |
1402 | ||
1403 | /* Forces statement defining invariants in REF (and *INDEX) to be moved out of | |
99e96094 | 1404 | the LOOP. The reference REF is used in the loop ORIG_LOOP. Callback for |
1405 | for_each_index. */ | |
1406 | ||
1407 | struct fmt_data | |
1408 | { | |
1409 | struct loop *loop; | |
1410 | struct loop *orig_loop; | |
1411 | }; | |
7d23383d | 1412 | |
1413 | static bool | |
1414 | force_move_till (tree ref, tree *index, void *data) | |
1415 | { | |
f0d6e81c | 1416 | struct fmt_data *fmt_data = (struct fmt_data *) data; |
7d23383d | 1417 | |
1418 | if (TREE_CODE (ref) == ARRAY_REF) | |
1419 | { | |
75a70cf9 | 1420 | tree step = TREE_OPERAND (ref, 3); |
1421 | tree lbound = TREE_OPERAND (ref, 2); | |
7d23383d | 1422 | |
75a70cf9 | 1423 | force_move_till_op (step, fmt_data->orig_loop, fmt_data->loop); |
1424 | force_move_till_op (lbound, fmt_data->orig_loop, fmt_data->loop); | |
7d23383d | 1425 | } |
1426 | ||
75a70cf9 | 1427 | force_move_till_op (*index, fmt_data->orig_loop, fmt_data->loop); |
7d23383d | 1428 | |
1429 | return true; | |
1430 | } | |
1431 | ||
063a8bce | 1432 | /* A function to free the mem_ref object OBJ. */ |
1433 | ||
1434 | static void | |
1ada9901 | 1435 | memref_free (struct im_mem_ref *mem) |
063a8bce | 1436 | { |
f1f41a6c | 1437 | mem->accesses_in_loop.release (); |
063a8bce | 1438 | } |
1439 | ||
1440 | /* Allocates and returns a memory reference description for MEM whose hash | |
1441 | value is HASH and id is ID. */ | |
1442 | ||
1443 | static mem_ref_p | |
1444 | mem_ref_alloc (tree mem, unsigned hash, unsigned id) | |
1445 | { | |
1ada9901 | 1446 | mem_ref_p ref = XOBNEW (&mem_ref_obstack, struct im_mem_ref); |
09f4cf62 | 1447 | ao_ref_init (&ref->mem, mem); |
063a8bce | 1448 | ref->id = id; |
1449 | ref->hash = hash; | |
3e48928c | 1450 | ref->stored = NULL; |
feba4360 | 1451 | bitmap_initialize (&ref->indep_loop, &lim_bitmap_obstack); |
1452 | bitmap_initialize (&ref->dep_loop, &lim_bitmap_obstack); | |
3e48928c | 1453 | ref->accesses_in_loop.create (1); |
063a8bce | 1454 | |
1455 | return ref; | |
1456 | } | |
1457 | ||
063a8bce | 1458 | /* Records memory reference location *LOC in LOOP to the memory reference |
1459 | description REF. The reference occurs in statement STMT. */ | |
7d23383d | 1460 | |
1461 | static void | |
3e48928c | 1462 | record_mem_ref_loc (mem_ref_p ref, gimple stmt, tree *loc) |
7d23383d | 1463 | { |
5c8a8be3 | 1464 | mem_ref_loc aref; |
5c8a8be3 | 1465 | aref.stmt = stmt; |
1466 | aref.ref = loc; | |
3e48928c | 1467 | ref->accesses_in_loop.safe_push (aref); |
1468 | } | |
1469 | ||
1470 | /* Set the LOOP bit in REF stored bitmap and allocate that if | |
1471 | necessary. Return whether a bit was changed. */ | |
1472 | ||
1473 | static bool | |
1474 | set_ref_stored_in_loop (mem_ref_p ref, struct loop *loop) | |
1475 | { | |
1476 | if (!ref->stored) | |
1477 | ref->stored = BITMAP_ALLOC (&lim_bitmap_obstack); | |
1478 | return bitmap_set_bit (ref->stored, loop->num); | |
7d23383d | 1479 | } |
1480 | ||
063a8bce | 1481 | /* Marks reference REF as stored in LOOP. */ |
7d23383d | 1482 | |
1483 | static void | |
063a8bce | 1484 | mark_ref_stored (mem_ref_p ref, struct loop *loop) |
7d23383d | 1485 | { |
feba4360 | 1486 | while (loop != current_loops->tree_root |
3e48928c | 1487 | && set_ref_stored_in_loop (ref, loop)) |
feba4360 | 1488 | loop = loop_outer (loop); |
063a8bce | 1489 | } |
1490 | ||
1491 | /* Gathers memory references in statement STMT in LOOP, storing the | |
1492 | information about them in the memory_accesses structure. Marks | |
1493 | the vops accessed through unrecognized statements there as | |
1494 | well. */ | |
1495 | ||
1496 | static void | |
75a70cf9 | 1497 | gather_mem_refs_stmt (struct loop *loop, gimple stmt) |
063a8bce | 1498 | { |
1499 | tree *mem = NULL; | |
1500 | hashval_t hash; | |
1ada9901 | 1501 | im_mem_ref **slot; |
063a8bce | 1502 | mem_ref_p ref; |
063a8bce | 1503 | bool is_stored; |
063a8bce | 1504 | unsigned id; |
7d23383d | 1505 | |
dd277d48 | 1506 | if (!gimple_vuse (stmt)) |
063a8bce | 1507 | return; |
1508 | ||
1509 | mem = simple_mem_ref_in_stmt (stmt, &is_stored); | |
1510 | if (!mem) | |
0766b2c0 | 1511 | { |
04911505 | 1512 | /* We use the shared mem_ref for all unanalyzable refs. */ |
1513 | id = UNANALYZABLE_MEM_ID; | |
1514 | ref = memory_accesses.refs_list[id]; | |
0766b2c0 | 1515 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1516 | { | |
1517 | fprintf (dump_file, "Unanalyzed memory reference %u: ", id); | |
1518 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1519 | } | |
04911505 | 1520 | is_stored = gimple_vdef (stmt); |
063a8bce | 1521 | } |
1522 | else | |
7d23383d | 1523 | { |
04911505 | 1524 | hash = iterative_hash_expr (*mem, 0); |
c1f445d2 | 1525 | slot = memory_accesses.refs->find_slot_with_hash (*mem, hash, INSERT); |
04911505 | 1526 | if (*slot) |
063a8bce | 1527 | { |
04911505 | 1528 | ref = (mem_ref_p) *slot; |
1529 | id = ref->id; | |
063a8bce | 1530 | } |
04911505 | 1531 | else |
1532 | { | |
1533 | id = memory_accesses.refs_list.length (); | |
1534 | ref = mem_ref_alloc (*mem, hash, id); | |
1535 | memory_accesses.refs_list.safe_push (ref); | |
1536 | *slot = ref; | |
61025ec0 | 1537 | |
04911505 | 1538 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1539 | { | |
1540 | fprintf (dump_file, "Memory reference %u: ", id); | |
1541 | print_generic_expr (dump_file, ref->mem.ref, TDF_SLIM); | |
1542 | fprintf (dump_file, "\n"); | |
1543 | } | |
1544 | } | |
1545 | ||
3e48928c | 1546 | record_mem_ref_loc (ref, stmt, mem); |
04911505 | 1547 | } |
feba4360 | 1548 | bitmap_set_bit (&memory_accesses.refs_in_loop[loop->num], ref->id); |
063a8bce | 1549 | if (is_stored) |
8f9829e8 | 1550 | { |
feba4360 | 1551 | bitmap_set_bit (&memory_accesses.refs_stored_in_loop[loop->num], ref->id); |
8f9829e8 | 1552 | mark_ref_stored (ref, loop); |
1553 | } | |
063a8bce | 1554 | return; |
7d23383d | 1555 | } |
1556 | ||
7894a3d9 | 1557 | static unsigned *bb_loop_postorder; |
1558 | ||
1559 | /* qsort sort function to sort blocks after their loop fathers postorder. */ | |
1560 | ||
1561 | static int | |
1562 | sort_bbs_in_loop_postorder_cmp (const void *bb1_, const void *bb2_) | |
1563 | { | |
1564 | basic_block bb1 = *(basic_block *)const_cast<void *>(bb1_); | |
1565 | basic_block bb2 = *(basic_block *)const_cast<void *>(bb2_); | |
1566 | struct loop *loop1 = bb1->loop_father; | |
1567 | struct loop *loop2 = bb2->loop_father; | |
1568 | if (loop1->num == loop2->num) | |
1569 | return 0; | |
1570 | return bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num] ? -1 : 1; | |
1571 | } | |
1572 | ||
3e48928c | 1573 | /* qsort sort function to sort ref locs after their loop fathers postorder. */ |
1574 | ||
1575 | static int | |
1576 | sort_locs_in_loop_postorder_cmp (const void *loc1_, const void *loc2_) | |
1577 | { | |
1578 | mem_ref_loc *loc1 = (mem_ref_loc *)const_cast<void *>(loc1_); | |
1579 | mem_ref_loc *loc2 = (mem_ref_loc *)const_cast<void *>(loc2_); | |
1580 | struct loop *loop1 = gimple_bb (loc1->stmt)->loop_father; | |
1581 | struct loop *loop2 = gimple_bb (loc2->stmt)->loop_father; | |
1582 | if (loop1->num == loop2->num) | |
1583 | return 0; | |
1584 | return bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num] ? -1 : 1; | |
1585 | } | |
1586 | ||
063a8bce | 1587 | /* Gathers memory references in loops. */ |
7d23383d | 1588 | |
1589 | static void | |
feba4360 | 1590 | analyze_memory_references (void) |
7d23383d | 1591 | { |
75a70cf9 | 1592 | gimple_stmt_iterator bsi; |
7894a3d9 | 1593 | basic_block bb, *bbs; |
8f9829e8 | 1594 | struct loop *loop, *outer; |
7894a3d9 | 1595 | unsigned i, n; |
063a8bce | 1596 | |
7894a3d9 | 1597 | /* Collect all basic-blocks in loops and sort them after their |
1598 | loops postorder. */ | |
1599 | i = 0; | |
a28770e1 | 1600 | bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS); |
fc00614f | 1601 | FOR_EACH_BB_FN (bb, cfun) |
7894a3d9 | 1602 | if (bb->loop_father != current_loops->tree_root) |
1603 | bbs[i++] = bb; | |
1604 | n = i; | |
1605 | qsort (bbs, n, sizeof (basic_block), sort_bbs_in_loop_postorder_cmp); | |
7894a3d9 | 1606 | |
1607 | /* Visit blocks in loop postorder and assign mem-ref IDs in that order. | |
1608 | That results in better locality for all the bitmaps. */ | |
1609 | for (i = 0; i < n; ++i) | |
063a8bce | 1610 | { |
7894a3d9 | 1611 | basic_block bb = bbs[i]; |
75a70cf9 | 1612 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
7894a3d9 | 1613 | gather_mem_refs_stmt (bb->loop_father, gsi_stmt (bsi)); |
063a8bce | 1614 | } |
1615 | ||
3e48928c | 1616 | /* Sort the location list of gathered memory references after their |
1617 | loop postorder number. */ | |
1ada9901 | 1618 | im_mem_ref *ref; |
3e48928c | 1619 | FOR_EACH_VEC_ELT (memory_accesses.refs_list, i, ref) |
1620 | ref->accesses_in_loop.qsort (sort_locs_in_loop_postorder_cmp); | |
1621 | ||
7894a3d9 | 1622 | free (bbs); |
3e48928c | 1623 | // free (bb_loop_postorder); |
7894a3d9 | 1624 | |
0766b2c0 | 1625 | /* Propagate the information about accessed memory references up |
1626 | the loop hierarchy. */ | |
f21d4d00 | 1627 | FOR_EACH_LOOP (loop, LI_FROM_INNERMOST) |
063a8bce | 1628 | { |
8f9829e8 | 1629 | /* Finalize the overall touched references (including subloops). */ |
feba4360 | 1630 | bitmap_ior_into (&memory_accesses.all_refs_stored_in_loop[loop->num], |
1631 | &memory_accesses.refs_stored_in_loop[loop->num]); | |
8f9829e8 | 1632 | |
1633 | /* Propagate the information about accessed memory references up | |
1634 | the loop hierarchy. */ | |
1635 | outer = loop_outer (loop); | |
1636 | if (outer == current_loops->tree_root) | |
063a8bce | 1637 | continue; |
1638 | ||
feba4360 | 1639 | bitmap_ior_into (&memory_accesses.all_refs_stored_in_loop[outer->num], |
1640 | &memory_accesses.all_refs_stored_in_loop[loop->num]); | |
063a8bce | 1641 | } |
063a8bce | 1642 | } |
1643 | ||
063a8bce | 1644 | /* Returns true if MEM1 and MEM2 may alias. TTAE_CACHE is used as a cache in |
1645 | tree_to_aff_combination_expand. */ | |
1646 | ||
1647 | static bool | |
09f4cf62 | 1648 | mem_refs_may_alias_p (mem_ref_p mem1, mem_ref_p mem2, |
5f8841a5 | 1649 | hash_map<tree, name_expansion *> **ttae_cache) |
063a8bce | 1650 | { |
1651 | /* Perform BASE + OFFSET analysis -- if MEM1 and MEM2 are based on the same | |
1652 | object and their offset differ in such a way that the locations cannot | |
1653 | overlap, then they cannot alias. */ | |
5de9d3ed | 1654 | widest_int size1, size2; |
3391cd1e | 1655 | aff_tree off1, off2; |
063a8bce | 1656 | |
3391cd1e | 1657 | /* Perform basic offset and type-based disambiguation. */ |
09f4cf62 | 1658 | if (!refs_may_alias_p_1 (&mem1->mem, &mem2->mem, true)) |
063a8bce | 1659 | return false; |
7d23383d | 1660 | |
063a8bce | 1661 | /* The expansion of addresses may be a bit expensive, thus we only do |
1662 | the check at -O2 and higher optimization levels. */ | |
1663 | if (optimize < 2) | |
1664 | return true; | |
1665 | ||
09f4cf62 | 1666 | get_inner_reference_aff (mem1->mem.ref, &off1, &size1); |
1667 | get_inner_reference_aff (mem2->mem.ref, &off2, &size2); | |
063a8bce | 1668 | aff_combination_expand (&off1, ttae_cache); |
1669 | aff_combination_expand (&off2, ttae_cache); | |
e913b5cd | 1670 | aff_combination_scale (&off1, -1); |
063a8bce | 1671 | aff_combination_add (&off2, &off1); |
1672 | ||
5fc88ffd | 1673 | if (aff_comb_cannot_overlap_p (&off2, size1, size2)) |
063a8bce | 1674 | return false; |
1675 | ||
1676 | return true; | |
1677 | } | |
1678 | ||
3e48928c | 1679 | /* Compare function for bsearch searching for reference locations |
1680 | in a loop. */ | |
1681 | ||
1682 | static int | |
1683 | find_ref_loc_in_loop_cmp (const void *loop_, const void *loc_) | |
1684 | { | |
1685 | struct loop *loop = (struct loop *)const_cast<void *>(loop_); | |
1686 | mem_ref_loc *loc = (mem_ref_loc *)const_cast<void *>(loc_); | |
1687 | struct loop *loc_loop = gimple_bb (loc->stmt)->loop_father; | |
1688 | if (loop->num == loc_loop->num | |
1689 | || flow_loop_nested_p (loop, loc_loop)) | |
1690 | return 0; | |
1691 | return (bb_loop_postorder[loop->num] < bb_loop_postorder[loc_loop->num] | |
1692 | ? -1 : 1); | |
1693 | } | |
1694 | ||
5c8a8be3 | 1695 | /* Iterates over all locations of REF in LOOP and its subloops calling |
1696 | fn.operator() with the location as argument. When that operator | |
1697 | returns true the iteration is stopped and true is returned. | |
1698 | Otherwise false is returned. */ | |
063a8bce | 1699 | |
5c8a8be3 | 1700 | template <typename FN> |
1701 | static bool | |
1702 | for_all_locs_in_loop (struct loop *loop, mem_ref_p ref, FN fn) | |
063a8bce | 1703 | { |
063a8bce | 1704 | unsigned i; |
1705 | mem_ref_loc_p loc; | |
063a8bce | 1706 | |
3e48928c | 1707 | /* Search for the cluster of locs in the accesses_in_loop vector |
1708 | which is sorted after postorder index of the loop father. */ | |
1709 | loc = ref->accesses_in_loop.bsearch (loop, find_ref_loc_in_loop_cmp); | |
1710 | if (!loc) | |
1711 | return false; | |
063a8bce | 1712 | |
3e48928c | 1713 | /* We have found one location inside loop or its sub-loops. Iterate |
1714 | both forward and backward to cover the whole cluster. */ | |
1715 | i = loc - ref->accesses_in_loop.address (); | |
1716 | while (i > 0) | |
1717 | { | |
1718 | --i; | |
1719 | mem_ref_loc_p l = &ref->accesses_in_loop[i]; | |
1720 | if (!flow_bb_inside_loop_p (loop, gimple_bb (l->stmt))) | |
1721 | break; | |
1722 | if (fn (l)) | |
1723 | return true; | |
1724 | } | |
1725 | for (i = loc - ref->accesses_in_loop.address (); | |
1726 | i < ref->accesses_in_loop.length (); ++i) | |
1727 | { | |
1728 | mem_ref_loc_p l = &ref->accesses_in_loop[i]; | |
1729 | if (!flow_bb_inside_loop_p (loop, gimple_bb (l->stmt))) | |
1730 | break; | |
1731 | if (fn (l)) | |
1732 | return true; | |
1733 | } | |
5c8a8be3 | 1734 | |
1735 | return false; | |
1736 | } | |
1737 | ||
1738 | /* Rewrites location LOC by TMP_VAR. */ | |
1739 | ||
1740 | struct rewrite_mem_ref_loc | |
1741 | { | |
1742 | rewrite_mem_ref_loc (tree tmp_var_) : tmp_var (tmp_var_) {} | |
9af5ce0c | 1743 | bool operator () (mem_ref_loc_p loc); |
5c8a8be3 | 1744 | tree tmp_var; |
1745 | }; | |
1746 | ||
1747 | bool | |
9af5ce0c | 1748 | rewrite_mem_ref_loc::operator () (mem_ref_loc_p loc) |
5c8a8be3 | 1749 | { |
1750 | *loc->ref = tmp_var; | |
1751 | update_stmt (loc->stmt); | |
1752 | return false; | |
063a8bce | 1753 | } |
1754 | ||
1755 | /* Rewrites all references to REF in LOOP by variable TMP_VAR. */ | |
1756 | ||
1757 | static void | |
1758 | rewrite_mem_refs (struct loop *loop, mem_ref_p ref, tree tmp_var) | |
1759 | { | |
5c8a8be3 | 1760 | for_all_locs_in_loop (loop, ref, rewrite_mem_ref_loc (tmp_var)); |
7d23383d | 1761 | } |
1762 | ||
bc9af2dd | 1763 | /* Stores the first reference location in LOCP. */ |
1764 | ||
1765 | struct first_mem_ref_loc_1 | |
1766 | { | |
1767 | first_mem_ref_loc_1 (mem_ref_loc_p *locp_) : locp (locp_) {} | |
9af5ce0c | 1768 | bool operator () (mem_ref_loc_p loc); |
bc9af2dd | 1769 | mem_ref_loc_p *locp; |
1770 | }; | |
1771 | ||
1772 | bool | |
9af5ce0c | 1773 | first_mem_ref_loc_1::operator () (mem_ref_loc_p loc) |
bc9af2dd | 1774 | { |
1775 | *locp = loc; | |
1776 | return true; | |
1777 | } | |
1778 | ||
1779 | /* Returns the first reference location to REF in LOOP. */ | |
1780 | ||
1781 | static mem_ref_loc_p | |
1782 | first_mem_ref_loc (struct loop *loop, mem_ref_p ref) | |
1783 | { | |
1784 | mem_ref_loc_p locp = NULL; | |
1785 | for_all_locs_in_loop (loop, ref, first_mem_ref_loc_1 (&locp)); | |
1786 | return locp; | |
1787 | } | |
1788 | ||
61025ec0 | 1789 | struct prev_flag_edges { |
1790 | /* Edge to insert new flag comparison code. */ | |
1791 | edge append_cond_position; | |
1792 | ||
1793 | /* Edge for fall through from previous flag comparison. */ | |
1794 | edge last_cond_fallthru; | |
1795 | }; | |
1796 | ||
1797 | /* Helper function for execute_sm. Emit code to store TMP_VAR into | |
1798 | MEM along edge EX. | |
1799 | ||
1800 | The store is only done if MEM has changed. We do this so no | |
1801 | changes to MEM occur on code paths that did not originally store | |
1802 | into it. | |
1803 | ||
1804 | The common case for execute_sm will transform: | |
1805 | ||
1806 | for (...) { | |
1807 | if (foo) | |
1808 | stuff; | |
1809 | else | |
1810 | MEM = TMP_VAR; | |
1811 | } | |
1812 | ||
1813 | into: | |
1814 | ||
1815 | lsm = MEM; | |
1816 | for (...) { | |
1817 | if (foo) | |
1818 | stuff; | |
1819 | else | |
1820 | lsm = TMP_VAR; | |
1821 | } | |
1822 | MEM = lsm; | |
1823 | ||
1824 | This function will generate: | |
1825 | ||
1826 | lsm = MEM; | |
1827 | ||
1828 | lsm_flag = false; | |
1829 | ... | |
1830 | for (...) { | |
1831 | if (foo) | |
1832 | stuff; | |
1833 | else { | |
1834 | lsm = TMP_VAR; | |
1835 | lsm_flag = true; | |
1836 | } | |
1837 | } | |
1838 | if (lsm_flag) <-- | |
1839 | MEM = lsm; <-- | |
1840 | */ | |
1841 | ||
1842 | static void | |
1843 | execute_sm_if_changed (edge ex, tree mem, tree tmp_var, tree flag) | |
1844 | { | |
1845 | basic_block new_bb, then_bb, old_dest; | |
1846 | bool loop_has_only_one_exit; | |
1847 | edge then_old_edge, orig_ex = ex; | |
1848 | gimple_stmt_iterator gsi; | |
1849 | gimple stmt; | |
1850 | struct prev_flag_edges *prev_edges = (struct prev_flag_edges *) ex->aux; | |
a1ccf30d | 1851 | bool irr = ex->flags & EDGE_IRREDUCIBLE_LOOP; |
61025ec0 | 1852 | |
1853 | /* ?? Insert store after previous store if applicable. See note | |
1854 | below. */ | |
1855 | if (prev_edges) | |
1856 | ex = prev_edges->append_cond_position; | |
1857 | ||
1858 | loop_has_only_one_exit = single_pred_p (ex->dest); | |
1859 | ||
1860 | if (loop_has_only_one_exit) | |
1861 | ex = split_block_after_labels (ex->dest); | |
1862 | ||
1863 | old_dest = ex->dest; | |
1864 | new_bb = split_edge (ex); | |
1865 | then_bb = create_empty_bb (new_bb); | |
a1ccf30d | 1866 | if (irr) |
1867 | then_bb->flags = BB_IRREDUCIBLE_LOOP; | |
1868 | add_bb_to_loop (then_bb, new_bb->loop_father); | |
61025ec0 | 1869 | |
1870 | gsi = gsi_start_bb (new_bb); | |
1871 | stmt = gimple_build_cond (NE_EXPR, flag, boolean_false_node, | |
1872 | NULL_TREE, NULL_TREE); | |
1873 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1874 | ||
1875 | gsi = gsi_start_bb (then_bb); | |
1876 | /* Insert actual store. */ | |
1877 | stmt = gimple_build_assign (unshare_expr (mem), tmp_var); | |
1878 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1879 | ||
a1ccf30d | 1880 | make_edge (new_bb, then_bb, |
1881 | EDGE_TRUE_VALUE | (irr ? EDGE_IRREDUCIBLE_LOOP : 0)); | |
1882 | make_edge (new_bb, old_dest, | |
1883 | EDGE_FALSE_VALUE | (irr ? EDGE_IRREDUCIBLE_LOOP : 0)); | |
1884 | then_old_edge = make_edge (then_bb, old_dest, | |
1885 | EDGE_FALLTHRU | (irr ? EDGE_IRREDUCIBLE_LOOP : 0)); | |
61025ec0 | 1886 | |
1887 | set_immediate_dominator (CDI_DOMINATORS, then_bb, new_bb); | |
1888 | ||
1889 | if (prev_edges) | |
1890 | { | |
1891 | basic_block prevbb = prev_edges->last_cond_fallthru->src; | |
1892 | redirect_edge_succ (prev_edges->last_cond_fallthru, new_bb); | |
1893 | set_immediate_dominator (CDI_DOMINATORS, new_bb, prevbb); | |
1894 | set_immediate_dominator (CDI_DOMINATORS, old_dest, | |
1895 | recompute_dominator (CDI_DOMINATORS, old_dest)); | |
1896 | } | |
1897 | ||
1898 | /* ?? Because stores may alias, they must happen in the exact | |
1899 | sequence they originally happened. Save the position right after | |
1900 | the (_lsm) store we just created so we can continue appending after | |
1901 | it and maintain the original order. */ | |
1902 | { | |
1903 | struct prev_flag_edges *p; | |
1904 | ||
1905 | if (orig_ex->aux) | |
1906 | orig_ex->aux = NULL; | |
1907 | alloc_aux_for_edge (orig_ex, sizeof (struct prev_flag_edges)); | |
1908 | p = (struct prev_flag_edges *) orig_ex->aux; | |
1909 | p->append_cond_position = then_old_edge; | |
1910 | p->last_cond_fallthru = find_edge (new_bb, old_dest); | |
1911 | orig_ex->aux = (void *) p; | |
1912 | } | |
1913 | ||
1914 | if (!loop_has_only_one_exit) | |
1a91d914 | 1915 | for (gphi_iterator gpi = gsi_start_phis (old_dest); |
1916 | !gsi_end_p (gpi); gsi_next (&gpi)) | |
61025ec0 | 1917 | { |
1a91d914 | 1918 | gphi *phi = gpi.phi (); |
61025ec0 | 1919 | unsigned i; |
1920 | ||
1921 | for (i = 0; i < gimple_phi_num_args (phi); i++) | |
1922 | if (gimple_phi_arg_edge (phi, i)->src == new_bb) | |
1923 | { | |
1924 | tree arg = gimple_phi_arg_def (phi, i); | |
60d535d2 | 1925 | add_phi_arg (phi, arg, then_old_edge, UNKNOWN_LOCATION); |
61025ec0 | 1926 | update_stmt (phi); |
1927 | } | |
1928 | } | |
1929 | /* Remove the original fall through edge. This was the | |
1930 | single_succ_edge (new_bb). */ | |
1931 | EDGE_SUCC (new_bb, 0)->flags &= ~EDGE_FALLTHRU; | |
1932 | } | |
1933 | ||
5c8a8be3 | 1934 | /* When REF is set on the location, set flag indicating the store. */ |
1935 | ||
1936 | struct sm_set_flag_if_changed | |
1937 | { | |
1938 | sm_set_flag_if_changed (tree flag_) : flag (flag_) {} | |
9af5ce0c | 1939 | bool operator () (mem_ref_loc_p loc); |
5c8a8be3 | 1940 | tree flag; |
1941 | }; | |
1942 | ||
1943 | bool | |
9af5ce0c | 1944 | sm_set_flag_if_changed::operator () (mem_ref_loc_p loc) |
5c8a8be3 | 1945 | { |
1946 | /* Only set the flag for writes. */ | |
1947 | if (is_gimple_assign (loc->stmt) | |
1948 | && gimple_assign_lhs_ptr (loc->stmt) == loc->ref) | |
1949 | { | |
1950 | gimple_stmt_iterator gsi = gsi_for_stmt (loc->stmt); | |
1951 | gimple stmt = gimple_build_assign (flag, boolean_true_node); | |
1952 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1953 | } | |
1954 | return false; | |
1955 | } | |
1956 | ||
61025ec0 | 1957 | /* Helper function for execute_sm. On every location where REF is |
1958 | set, set an appropriate flag indicating the store. */ | |
1959 | ||
1960 | static tree | |
1961 | execute_sm_if_changed_flag_set (struct loop *loop, mem_ref_p ref) | |
1962 | { | |
61025ec0 | 1963 | tree flag; |
f86b328b | 1964 | char *str = get_lsm_tmp_name (ref->mem.ref, ~0, "_flag"); |
072f7ab1 | 1965 | flag = create_tmp_reg (boolean_type_node, str); |
5c8a8be3 | 1966 | for_all_locs_in_loop (loop, ref, sm_set_flag_if_changed (flag)); |
61025ec0 | 1967 | return flag; |
1968 | } | |
1969 | ||
063a8bce | 1970 | /* Executes store motion of memory reference REF from LOOP. |
749ea85f | 1971 | Exits from the LOOP are stored in EXITS. The initialization of the |
1972 | temporary variable is put to the preheader of the loop, and assignments | |
1973 | to the reference from the temporary variable are emitted to exits. */ | |
7d23383d | 1974 | |
1975 | static void | |
f1f41a6c | 1976 | execute_sm (struct loop *loop, vec<edge> exits, mem_ref_p ref) |
7d23383d | 1977 | { |
3e48928c | 1978 | tree tmp_var, store_flag = NULL_TREE; |
7d23383d | 1979 | unsigned i; |
1a91d914 | 1980 | gassign *load; |
99e96094 | 1981 | struct fmt_data fmt_data; |
bc9af2dd | 1982 | edge ex; |
75a70cf9 | 1983 | struct lim_aux_data *lim_data; |
61025ec0 | 1984 | bool multi_threaded_model_p = false; |
bc9af2dd | 1985 | gimple_stmt_iterator gsi; |
7d23383d | 1986 | |
69154f26 | 1987 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1988 | { | |
1989 | fprintf (dump_file, "Executing store motion of "); | |
09f4cf62 | 1990 | print_generic_expr (dump_file, ref->mem.ref, 0); |
69154f26 | 1991 | fprintf (dump_file, " from loop %d\n", loop->num); |
1992 | } | |
1993 | ||
09f4cf62 | 1994 | tmp_var = create_tmp_reg (TREE_TYPE (ref->mem.ref), |
1995 | get_lsm_tmp_name (ref->mem.ref, ~0)); | |
7d23383d | 1996 | |
99e96094 | 1997 | fmt_data.loop = loop; |
1998 | fmt_data.orig_loop = loop; | |
09f4cf62 | 1999 | for_each_index (&ref->mem.ref, force_move_till, &fmt_data); |
7d23383d | 2000 | |
c927329e | 2001 | if (bb_in_transaction (loop_preheader_edge (loop)->src) |
61025ec0 | 2002 | || !PARAM_VALUE (PARAM_ALLOW_STORE_DATA_RACES)) |
2003 | multi_threaded_model_p = true; | |
2004 | ||
2005 | if (multi_threaded_model_p) | |
2006 | store_flag = execute_sm_if_changed_flag_set (loop, ref); | |
2007 | ||
063a8bce | 2008 | rewrite_mem_refs (loop, ref, tmp_var); |
7d23383d | 2009 | |
bc9af2dd | 2010 | /* Emit the load code on a random exit edge or into the latch if |
2011 | the loop does not exit, so that we are sure it will be processed | |
2012 | by move_computations after all dependencies. */ | |
2013 | gsi = gsi_for_stmt (first_mem_ref_loc (loop, ref)->stmt); | |
61025ec0 | 2014 | |
2015 | /* FIXME/TODO: For the multi-threaded variant, we could avoid this | |
2016 | load altogether, since the store is predicated by a flag. We | |
2017 | could, do the load only if it was originally in the loop. */ | |
09f4cf62 | 2018 | load = gimple_build_assign (tmp_var, unshare_expr (ref->mem.ref)); |
75a70cf9 | 2019 | lim_data = init_lim_data (load); |
2020 | lim_data->max_loop = loop; | |
2021 | lim_data->tgt_loop = loop; | |
bc9af2dd | 2022 | gsi_insert_before (&gsi, load, GSI_SAME_STMT); |
7d23383d | 2023 | |
61025ec0 | 2024 | if (multi_threaded_model_p) |
7d23383d | 2025 | { |
61025ec0 | 2026 | load = gimple_build_assign (store_flag, boolean_false_node); |
2027 | lim_data = init_lim_data (load); | |
2028 | lim_data->max_loop = loop; | |
2029 | lim_data->tgt_loop = loop; | |
bc9af2dd | 2030 | gsi_insert_before (&gsi, load, GSI_SAME_STMT); |
7d23383d | 2031 | } |
61025ec0 | 2032 | |
2033 | /* Sink the store to every exit from the loop. */ | |
f1f41a6c | 2034 | FOR_EACH_VEC_ELT (exits, i, ex) |
61025ec0 | 2035 | if (!multi_threaded_model_p) |
2036 | { | |
1a91d914 | 2037 | gassign *store; |
09f4cf62 | 2038 | store = gimple_build_assign (unshare_expr (ref->mem.ref), tmp_var); |
61025ec0 | 2039 | gsi_insert_on_edge (ex, store); |
2040 | } | |
2041 | else | |
09f4cf62 | 2042 | execute_sm_if_changed (ex, ref->mem.ref, tmp_var, store_flag); |
7d23383d | 2043 | } |
2044 | ||
063a8bce | 2045 | /* Hoists memory references MEM_REFS out of LOOP. EXITS is the list of exit |
2046 | edges of the LOOP. */ | |
7d23383d | 2047 | |
2048 | static void | |
063a8bce | 2049 | hoist_memory_references (struct loop *loop, bitmap mem_refs, |
f1f41a6c | 2050 | vec<edge> exits) |
7d23383d | 2051 | { |
063a8bce | 2052 | mem_ref_p ref; |
2053 | unsigned i; | |
2054 | bitmap_iterator bi; | |
69154f26 | 2055 | |
063a8bce | 2056 | EXECUTE_IF_SET_IN_BITMAP (mem_refs, 0, i, bi) |
7d23383d | 2057 | { |
f1f41a6c | 2058 | ref = memory_accesses.refs_list[i]; |
063a8bce | 2059 | execute_sm (loop, exits, ref); |
7d23383d | 2060 | } |
55a03692 | 2061 | } |
2062 | ||
5c8a8be3 | 2063 | struct ref_always_accessed |
2064 | { | |
3e48928c | 2065 | ref_always_accessed (struct loop *loop_, bool stored_p_) |
2066 | : loop (loop_), stored_p (stored_p_) {} | |
9af5ce0c | 2067 | bool operator () (mem_ref_loc_p loc); |
5c8a8be3 | 2068 | struct loop *loop; |
5c8a8be3 | 2069 | bool stored_p; |
2070 | }; | |
7d23383d | 2071 | |
5c8a8be3 | 2072 | bool |
9af5ce0c | 2073 | ref_always_accessed::operator () (mem_ref_loc_p loc) |
7d23383d | 2074 | { |
063a8bce | 2075 | struct loop *must_exec; |
307f7fda | 2076 | |
5c8a8be3 | 2077 | if (!get_lim_data (loc->stmt)) |
2078 | return false; | |
7d23383d | 2079 | |
5c8a8be3 | 2080 | /* If we require an always executed store make sure the statement |
2081 | stores to the reference. */ | |
2082 | if (stored_p) | |
063a8bce | 2083 | { |
3e48928c | 2084 | tree lhs = gimple_get_lhs (loc->stmt); |
2085 | if (!lhs | |
2086 | || lhs != *loc->ref) | |
5c8a8be3 | 2087 | return false; |
2088 | } | |
7d23383d | 2089 | |
5c8a8be3 | 2090 | must_exec = get_lim_data (loc->stmt)->always_executed_in; |
2091 | if (!must_exec) | |
2092 | return false; | |
307f7fda | 2093 | |
5c8a8be3 | 2094 | if (must_exec == loop |
2095 | || flow_loop_nested_p (must_exec, loop)) | |
2096 | return true; | |
7d23383d | 2097 | |
5c8a8be3 | 2098 | return false; |
2099 | } | |
55a03692 | 2100 | |
5c8a8be3 | 2101 | /* Returns true if REF is always accessed in LOOP. If STORED_P is true |
2102 | make sure REF is always stored to in LOOP. */ | |
2103 | ||
2104 | static bool | |
2105 | ref_always_accessed_p (struct loop *loop, mem_ref_p ref, bool stored_p) | |
2106 | { | |
5c8a8be3 | 2107 | return for_all_locs_in_loop (loop, ref, |
3e48928c | 2108 | ref_always_accessed (loop, stored_p)); |
55a03692 | 2109 | } |
2110 | ||
063a8bce | 2111 | /* Returns true if REF1 and REF2 are independent. */ |
55a03692 | 2112 | |
063a8bce | 2113 | static bool |
2114 | refs_independent_p (mem_ref_p ref1, mem_ref_p ref2) | |
55a03692 | 2115 | { |
09f4cf62 | 2116 | if (ref1 == ref2) |
063a8bce | 2117 | return true; |
09f4cf62 | 2118 | |
063a8bce | 2119 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2120 | fprintf (dump_file, "Querying dependency of refs %u and %u: ", | |
2121 | ref1->id, ref2->id); | |
2122 | ||
09f4cf62 | 2123 | if (mem_refs_may_alias_p (ref1, ref2, &memory_accesses.ttae_cache)) |
063a8bce | 2124 | { |
063a8bce | 2125 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2126 | fprintf (dump_file, "dependent.\n"); | |
2127 | return false; | |
2128 | } | |
2129 | else | |
2130 | { | |
063a8bce | 2131 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2132 | fprintf (dump_file, "independent.\n"); | |
2133 | return true; | |
2134 | } | |
55a03692 | 2135 | } |
2136 | ||
8f9829e8 | 2137 | /* Mark REF dependent on stores or loads (according to STORED_P) in LOOP |
2138 | and its super-loops. */ | |
55a03692 | 2139 | |
2140 | static void | |
8f9829e8 | 2141 | record_dep_loop (struct loop *loop, mem_ref_p ref, bool stored_p) |
55a03692 | 2142 | { |
8f9829e8 | 2143 | /* We can propagate dependent-in-loop bits up the loop |
2144 | hierarchy to all outer loops. */ | |
2145 | while (loop != current_loops->tree_root | |
feba4360 | 2146 | && bitmap_set_bit (&ref->dep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
8f9829e8 | 2147 | loop = loop_outer (loop); |
063a8bce | 2148 | } |
55a03692 | 2149 | |
063a8bce | 2150 | /* Returns true if REF is independent on all other memory references in |
2151 | LOOP. */ | |
55a03692 | 2152 | |
063a8bce | 2153 | static bool |
8f9829e8 | 2154 | ref_indep_loop_p_1 (struct loop *loop, mem_ref_p ref, bool stored_p) |
063a8bce | 2155 | { |
0766b2c0 | 2156 | bitmap refs_to_check; |
063a8bce | 2157 | unsigned i; |
2158 | bitmap_iterator bi; | |
063a8bce | 2159 | mem_ref_p aref; |
2160 | ||
8f9829e8 | 2161 | if (stored_p) |
feba4360 | 2162 | refs_to_check = &memory_accesses.refs_in_loop[loop->num]; |
0766b2c0 | 2163 | else |
feba4360 | 2164 | refs_to_check = &memory_accesses.refs_stored_in_loop[loop->num]; |
55a03692 | 2165 | |
04911505 | 2166 | if (bitmap_bit_p (refs_to_check, UNANALYZABLE_MEM_ID)) |
2167 | return false; | |
2168 | ||
063a8bce | 2169 | EXECUTE_IF_SET_IN_BITMAP (refs_to_check, 0, i, bi) |
55a03692 | 2170 | { |
f1f41a6c | 2171 | aref = memory_accesses.refs_list[i]; |
04911505 | 2172 | if (!refs_independent_p (ref, aref)) |
8f9829e8 | 2173 | return false; |
55a03692 | 2174 | } |
55a03692 | 2175 | |
8f9829e8 | 2176 | return true; |
55a03692 | 2177 | } |
2178 | ||
063a8bce | 2179 | /* Returns true if REF is independent on all other memory references in |
2180 | LOOP. Wrapper over ref_indep_loop_p_1, caching its results. */ | |
55a03692 | 2181 | |
063a8bce | 2182 | static bool |
8f9829e8 | 2183 | ref_indep_loop_p_2 (struct loop *loop, mem_ref_p ref, bool stored_p) |
55a03692 | 2184 | { |
3e48928c | 2185 | stored_p |= (ref->stored && bitmap_bit_p (ref->stored, loop->num)); |
04911505 | 2186 | |
feba4360 | 2187 | if (bitmap_bit_p (&ref->indep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
063a8bce | 2188 | return true; |
feba4360 | 2189 | if (bitmap_bit_p (&ref->dep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
063a8bce | 2190 | return false; |
55a03692 | 2191 | |
8f9829e8 | 2192 | struct loop *inner = loop->inner; |
2193 | while (inner) | |
2194 | { | |
2195 | if (!ref_indep_loop_p_2 (inner, ref, stored_p)) | |
2196 | return false; | |
2197 | inner = inner->next; | |
2198 | } | |
2199 | ||
2200 | bool indep_p = ref_indep_loop_p_1 (loop, ref, stored_p); | |
342ea212 | 2201 | |
063a8bce | 2202 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2203 | fprintf (dump_file, "Querying dependencies of ref %u in loop %d: %s\n", | |
8f9829e8 | 2204 | ref->id, loop->num, indep_p ? "independent" : "dependent"); |
063a8bce | 2205 | |
8f9829e8 | 2206 | /* Record the computed result in the cache. */ |
2207 | if (indep_p) | |
2208 | { | |
feba4360 | 2209 | if (bitmap_set_bit (&ref->indep_loop, LOOP_DEP_BIT (loop->num, stored_p)) |
8f9829e8 | 2210 | && stored_p) |
2211 | { | |
2212 | /* If it's independend against all refs then it's independent | |
2213 | against stores, too. */ | |
feba4360 | 2214 | bitmap_set_bit (&ref->indep_loop, LOOP_DEP_BIT (loop->num, false)); |
8f9829e8 | 2215 | } |
2216 | } | |
2217 | else | |
2218 | { | |
2219 | record_dep_loop (loop, ref, stored_p); | |
2220 | if (!stored_p) | |
2221 | { | |
2222 | /* If it's dependent against stores it's dependent against | |
2223 | all refs, too. */ | |
2224 | record_dep_loop (loop, ref, true); | |
2225 | } | |
2226 | } | |
063a8bce | 2227 | |
8f9829e8 | 2228 | return indep_p; |
2229 | } | |
2230 | ||
2231 | /* Returns true if REF is independent on all other memory references in | |
2232 | LOOP. */ | |
2233 | ||
2234 | static bool | |
2235 | ref_indep_loop_p (struct loop *loop, mem_ref_p ref) | |
2236 | { | |
2237 | gcc_checking_assert (MEM_ANALYZABLE (ref)); | |
2238 | ||
2239 | return ref_indep_loop_p_2 (loop, ref, false); | |
55a03692 | 2240 | } |
2241 | ||
063a8bce | 2242 | /* Returns true if we can perform store motion of REF from LOOP. */ |
55a03692 | 2243 | |
063a8bce | 2244 | static bool |
2245 | can_sm_ref_p (struct loop *loop, mem_ref_p ref) | |
55a03692 | 2246 | { |
307f7fda | 2247 | tree base; |
2248 | ||
0766b2c0 | 2249 | /* Can't hoist unanalyzable refs. */ |
2250 | if (!MEM_ANALYZABLE (ref)) | |
2251 | return false; | |
2252 | ||
063a8bce | 2253 | /* It should be movable. */ |
09f4cf62 | 2254 | if (!is_gimple_reg_type (TREE_TYPE (ref->mem.ref)) |
2255 | || TREE_THIS_VOLATILE (ref->mem.ref) | |
2256 | || !for_each_index (&ref->mem.ref, may_move_till, loop)) | |
063a8bce | 2257 | return false; |
342ea212 | 2258 | |
16d9b5d8 | 2259 | /* If it can throw fail, we do not properly update EH info. */ |
09f4cf62 | 2260 | if (tree_could_throw_p (ref->mem.ref)) |
16d9b5d8 | 2261 | return false; |
2262 | ||
307f7fda | 2263 | /* If it can trap, it must be always executed in LOOP. |
2264 | Readonly memory locations may trap when storing to them, but | |
2265 | tree_could_trap_p is a predicate for rvalues, so check that | |
2266 | explicitly. */ | |
09f4cf62 | 2267 | base = get_base_address (ref->mem.ref); |
2268 | if ((tree_could_trap_p (ref->mem.ref) | |
307f7fda | 2269 | || (DECL_P (base) && TREE_READONLY (base))) |
2270 | && !ref_always_accessed_p (loop, ref, true)) | |
063a8bce | 2271 | return false; |
342ea212 | 2272 | |
063a8bce | 2273 | /* And it must be independent on all other memory references |
2274 | in LOOP. */ | |
2275 | if (!ref_indep_loop_p (loop, ref)) | |
2276 | return false; | |
342ea212 | 2277 | |
063a8bce | 2278 | return true; |
342ea212 | 2279 | } |
2280 | ||
063a8bce | 2281 | /* Marks the references in LOOP for that store motion should be performed |
2282 | in REFS_TO_SM. SM_EXECUTED is the set of references for that store | |
2283 | motion was performed in one of the outer loops. */ | |
342ea212 | 2284 | |
2285 | static void | |
063a8bce | 2286 | find_refs_for_sm (struct loop *loop, bitmap sm_executed, bitmap refs_to_sm) |
55a03692 | 2287 | { |
feba4360 | 2288 | bitmap refs = &memory_accesses.all_refs_stored_in_loop[loop->num]; |
063a8bce | 2289 | unsigned i; |
2290 | bitmap_iterator bi; | |
2291 | mem_ref_p ref; | |
2292 | ||
2293 | EXECUTE_IF_AND_COMPL_IN_BITMAP (refs, sm_executed, 0, i, bi) | |
2294 | { | |
f1f41a6c | 2295 | ref = memory_accesses.refs_list[i]; |
063a8bce | 2296 | if (can_sm_ref_p (loop, ref)) |
2297 | bitmap_set_bit (refs_to_sm, i); | |
2298 | } | |
342ea212 | 2299 | } |
55a03692 | 2300 | |
063a8bce | 2301 | /* Checks whether LOOP (with exits stored in EXITS array) is suitable |
2302 | for a store motion optimization (i.e. whether we can insert statement | |
2303 | on its exits). */ | |
342ea212 | 2304 | |
063a8bce | 2305 | static bool |
2306 | loop_suitable_for_sm (struct loop *loop ATTRIBUTE_UNUSED, | |
f1f41a6c | 2307 | vec<edge> exits) |
342ea212 | 2308 | { |
063a8bce | 2309 | unsigned i; |
2310 | edge ex; | |
55a03692 | 2311 | |
f1f41a6c | 2312 | FOR_EACH_VEC_ELT (exits, i, ex) |
9102193b | 2313 | if (ex->flags & (EDGE_ABNORMAL | EDGE_EH)) |
063a8bce | 2314 | return false; |
2315 | ||
2316 | return true; | |
55a03692 | 2317 | } |
2318 | ||
7d23383d | 2319 | /* Try to perform store motion for all memory references modified inside |
063a8bce | 2320 | LOOP. SM_EXECUTED is the bitmap of the memory references for that |
2321 | store motion was executed in one of the outer loops. */ | |
7d23383d | 2322 | |
2323 | static void | |
063a8bce | 2324 | store_motion_loop (struct loop *loop, bitmap sm_executed) |
7d23383d | 2325 | { |
f1f41a6c | 2326 | vec<edge> exits = get_loop_exit_edges (loop); |
063a8bce | 2327 | struct loop *subloop; |
39f8afdf | 2328 | bitmap sm_in_loop = BITMAP_ALLOC (&lim_bitmap_obstack); |
7d23383d | 2329 | |
063a8bce | 2330 | if (loop_suitable_for_sm (loop, exits)) |
7d23383d | 2331 | { |
063a8bce | 2332 | find_refs_for_sm (loop, sm_executed, sm_in_loop); |
2333 | hoist_memory_references (loop, sm_in_loop, exits); | |
7d23383d | 2334 | } |
f1f41a6c | 2335 | exits.release (); |
063a8bce | 2336 | |
2337 | bitmap_ior_into (sm_executed, sm_in_loop); | |
2338 | for (subloop = loop->inner; subloop != NULL; subloop = subloop->next) | |
2339 | store_motion_loop (subloop, sm_executed); | |
2340 | bitmap_and_compl_into (sm_executed, sm_in_loop); | |
2341 | BITMAP_FREE (sm_in_loop); | |
7d23383d | 2342 | } |
2343 | ||
2344 | /* Try to perform store motion for all memory references modified inside | |
7194de72 | 2345 | loops. */ |
7d23383d | 2346 | |
2347 | static void | |
063a8bce | 2348 | store_motion (void) |
7d23383d | 2349 | { |
2350 | struct loop *loop; | |
39f8afdf | 2351 | bitmap sm_executed = BITMAP_ALLOC (&lim_bitmap_obstack); |
dda28f7c | 2352 | |
063a8bce | 2353 | for (loop = current_loops->tree_root->inner; loop != NULL; loop = loop->next) |
2354 | store_motion_loop (loop, sm_executed); | |
17519ba0 | 2355 | |
063a8bce | 2356 | BITMAP_FREE (sm_executed); |
75a70cf9 | 2357 | gsi_commit_edge_inserts (); |
7d23383d | 2358 | } |
2359 | ||
2360 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks of LOOP, i.e. | |
2361 | for each such basic block bb records the outermost loop for that execution | |
2362 | of its header implies execution of bb. CONTAINS_CALL is the bitmap of | |
2363 | blocks that contain a nonpure call. */ | |
2364 | ||
2365 | static void | |
feba4360 | 2366 | fill_always_executed_in_1 (struct loop *loop, sbitmap contains_call) |
7d23383d | 2367 | { |
2368 | basic_block bb = NULL, *bbs, last = NULL; | |
2369 | unsigned i; | |
2370 | edge e; | |
2371 | struct loop *inn_loop = loop; | |
2372 | ||
2fd20c29 | 2373 | if (ALWAYS_EXECUTED_IN (loop->header) == NULL) |
7d23383d | 2374 | { |
2375 | bbs = get_loop_body_in_dom_order (loop); | |
2376 | ||
2377 | for (i = 0; i < loop->num_nodes; i++) | |
2378 | { | |
cd665a06 | 2379 | edge_iterator ei; |
7d23383d | 2380 | bb = bbs[i]; |
2381 | ||
2382 | if (dominated_by_p (CDI_DOMINATORS, loop->latch, bb)) | |
2383 | last = bb; | |
2384 | ||
08b7917c | 2385 | if (bitmap_bit_p (contains_call, bb->index)) |
7d23383d | 2386 | break; |
2387 | ||
cd665a06 | 2388 | FOR_EACH_EDGE (e, ei, bb->succs) |
7d23383d | 2389 | if (!flow_bb_inside_loop_p (loop, e->dest)) |
2390 | break; | |
2391 | if (e) | |
2392 | break; | |
2393 | ||
2394 | /* A loop might be infinite (TODO use simple loop analysis | |
2395 | to disprove this if possible). */ | |
2396 | if (bb->flags & BB_IRREDUCIBLE_LOOP) | |
2397 | break; | |
2398 | ||
2399 | if (!flow_bb_inside_loop_p (inn_loop, bb)) | |
2400 | break; | |
2401 | ||
2402 | if (bb->loop_father->header == bb) | |
2403 | { | |
2404 | if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb)) | |
2405 | break; | |
2406 | ||
2407 | /* In a loop that is always entered we may proceed anyway. | |
2408 | But record that we entered it and stop once we leave it. */ | |
2409 | inn_loop = bb->loop_father; | |
2410 | } | |
2411 | } | |
2412 | ||
2413 | while (1) | |
2414 | { | |
2fd20c29 | 2415 | SET_ALWAYS_EXECUTED_IN (last, loop); |
7d23383d | 2416 | if (last == loop->header) |
2417 | break; | |
2418 | last = get_immediate_dominator (CDI_DOMINATORS, last); | |
2419 | } | |
2420 | ||
2421 | free (bbs); | |
2422 | } | |
2423 | ||
2424 | for (loop = loop->inner; loop; loop = loop->next) | |
feba4360 | 2425 | fill_always_executed_in_1 (loop, contains_call); |
7d23383d | 2426 | } |
2427 | ||
feba4360 | 2428 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks, i.e. |
2429 | for each such basic block bb records the outermost loop for that execution | |
2430 | of its header implies execution of bb. */ | |
7d23383d | 2431 | |
2432 | static void | |
feba4360 | 2433 | fill_always_executed_in (void) |
7d23383d | 2434 | { |
fe672ac0 | 2435 | sbitmap contains_call = sbitmap_alloc (last_basic_block_for_fn (cfun)); |
7d23383d | 2436 | basic_block bb; |
feba4360 | 2437 | struct loop *loop; |
4fb07d00 | 2438 | |
53c5d9d4 | 2439 | bitmap_clear (contains_call); |
fc00614f | 2440 | FOR_EACH_BB_FN (bb, cfun) |
7d23383d | 2441 | { |
feba4360 | 2442 | gimple_stmt_iterator gsi; |
2443 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
7d23383d | 2444 | { |
feba4360 | 2445 | if (nonpure_call_p (gsi_stmt (gsi))) |
7d23383d | 2446 | break; |
2447 | } | |
2448 | ||
feba4360 | 2449 | if (!gsi_end_p (gsi)) |
08b7917c | 2450 | bitmap_set_bit (contains_call, bb->index); |
7d23383d | 2451 | } |
2452 | ||
7194de72 | 2453 | for (loop = current_loops->tree_root->inner; loop; loop = loop->next) |
feba4360 | 2454 | fill_always_executed_in_1 (loop, contains_call); |
7d23383d | 2455 | |
2456 | sbitmap_free (contains_call); | |
feba4360 | 2457 | } |
2458 | ||
2459 | ||
2460 | /* Compute the global information needed by the loop invariant motion pass. */ | |
75a70cf9 | 2461 | |
feba4360 | 2462 | static void |
2463 | tree_ssa_lim_initialize (void) | |
2464 | { | |
3e48928c | 2465 | struct loop *loop; |
feba4360 | 2466 | unsigned i; |
2467 | ||
2468 | bitmap_obstack_initialize (&lim_bitmap_obstack); | |
3e48928c | 2469 | gcc_obstack_init (&mem_ref_obstack); |
06ecf488 | 2470 | lim_aux_data_map = new hash_map<gimple, lim_aux_data *>; |
de60f90c | 2471 | |
2472 | if (flag_tm) | |
2473 | compute_transaction_bits (); | |
61025ec0 | 2474 | |
2475 | alloc_aux_for_edges (0); | |
feba4360 | 2476 | |
c1f445d2 | 2477 | memory_accesses.refs = new hash_table<mem_ref_hasher> (100); |
feba4360 | 2478 | memory_accesses.refs_list.create (100); |
2479 | /* Allocate a special, unanalyzable mem-ref with ID zero. */ | |
2480 | memory_accesses.refs_list.quick_push | |
2481 | (mem_ref_alloc (error_mark_node, 0, UNANALYZABLE_MEM_ID)); | |
2482 | ||
41f75a99 | 2483 | memory_accesses.refs_in_loop.create (number_of_loops (cfun)); |
2484 | memory_accesses.refs_in_loop.quick_grow (number_of_loops (cfun)); | |
2485 | memory_accesses.refs_stored_in_loop.create (number_of_loops (cfun)); | |
2486 | memory_accesses.refs_stored_in_loop.quick_grow (number_of_loops (cfun)); | |
2487 | memory_accesses.all_refs_stored_in_loop.create (number_of_loops (cfun)); | |
2488 | memory_accesses.all_refs_stored_in_loop.quick_grow (number_of_loops (cfun)); | |
feba4360 | 2489 | |
41f75a99 | 2490 | for (i = 0; i < number_of_loops (cfun); i++) |
feba4360 | 2491 | { |
2492 | bitmap_initialize (&memory_accesses.refs_in_loop[i], | |
2493 | &lim_bitmap_obstack); | |
2494 | bitmap_initialize (&memory_accesses.refs_stored_in_loop[i], | |
2495 | &lim_bitmap_obstack); | |
2496 | bitmap_initialize (&memory_accesses.all_refs_stored_in_loop[i], | |
2497 | &lim_bitmap_obstack); | |
2498 | } | |
2499 | ||
2500 | memory_accesses.ttae_cache = NULL; | |
3e48928c | 2501 | |
2502 | /* Initialize bb_loop_postorder with a mapping from loop->num to | |
2503 | its postorder index. */ | |
2504 | i = 0; | |
2505 | bb_loop_postorder = XNEWVEC (unsigned, number_of_loops (cfun)); | |
2506 | FOR_EACH_LOOP (loop, LI_FROM_INNERMOST) | |
2507 | bb_loop_postorder[loop->num] = i++; | |
7d23383d | 2508 | } |
2509 | ||
2510 | /* Cleans up after the invariant motion pass. */ | |
2511 | ||
2512 | static void | |
2513 | tree_ssa_lim_finalize (void) | |
2514 | { | |
2515 | basic_block bb; | |
063a8bce | 2516 | unsigned i; |
83b709f2 | 2517 | mem_ref_p ref; |
7d23383d | 2518 | |
61025ec0 | 2519 | free_aux_for_edges (); |
2520 | ||
fc00614f | 2521 | FOR_EACH_BB_FN (bb, cfun) |
2fd20c29 | 2522 | SET_ALWAYS_EXECUTED_IN (bb, NULL); |
063a8bce | 2523 | |
4fb07d00 | 2524 | bitmap_obstack_release (&lim_bitmap_obstack); |
06ecf488 | 2525 | delete lim_aux_data_map; |
75a70cf9 | 2526 | |
c1f445d2 | 2527 | delete memory_accesses.refs; |
2528 | memory_accesses.refs = NULL; | |
063a8bce | 2529 | |
f1f41a6c | 2530 | FOR_EACH_VEC_ELT (memory_accesses.refs_list, i, ref) |
83b709f2 | 2531 | memref_free (ref); |
f1f41a6c | 2532 | memory_accesses.refs_list.release (); |
3e48928c | 2533 | obstack_free (&mem_ref_obstack, NULL); |
83b709f2 | 2534 | |
f1f41a6c | 2535 | memory_accesses.refs_in_loop.release (); |
8f9829e8 | 2536 | memory_accesses.refs_stored_in_loop.release (); |
f1f41a6c | 2537 | memory_accesses.all_refs_stored_in_loop.release (); |
063a8bce | 2538 | |
2539 | if (memory_accesses.ttae_cache) | |
78d53e33 | 2540 | free_affine_expand_cache (&memory_accesses.ttae_cache); |
3e48928c | 2541 | |
2542 | free (bb_loop_postorder); | |
7d23383d | 2543 | } |
2544 | ||
7194de72 | 2545 | /* Moves invariants from loops. Only "expensive" invariants are moved out -- |
7d23383d | 2546 | i.e. those that are likely to be win regardless of the register pressure. */ |
2547 | ||
9bf0a3f9 | 2548 | unsigned int |
7194de72 | 2549 | tree_ssa_lim (void) |
7d23383d | 2550 | { |
9bf0a3f9 | 2551 | unsigned int todo; |
2552 | ||
7194de72 | 2553 | tree_ssa_lim_initialize (); |
7d23383d | 2554 | |
063a8bce | 2555 | /* Gathers information about memory accesses in the loops. */ |
2556 | analyze_memory_references (); | |
2557 | ||
feba4360 | 2558 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks. */ |
2559 | fill_always_executed_in (); | |
2560 | ||
7d23383d | 2561 | /* For each statement determine the outermost loop in that it is |
2562 | invariant and cost for computing the invariant. */ | |
54c91640 | 2563 | invariantness_dom_walker (CDI_DOMINATORS) |
2564 | .walk (cfun->cfg->x_entry_block_ptr); | |
7d23383d | 2565 | |
063a8bce | 2566 | /* Execute store motion. Force the necessary invariants to be moved |
2567 | out of the loops as well. */ | |
2568 | store_motion (); | |
7d23383d | 2569 | |
2570 | /* Move the expressions that are expensive enough. */ | |
9bf0a3f9 | 2571 | todo = move_computations (); |
7d23383d | 2572 | |
2573 | tree_ssa_lim_finalize (); | |
9bf0a3f9 | 2574 | |
2575 | return todo; | |
7d23383d | 2576 | } |
f86b328b | 2577 | |
2578 | /* Loop invariant motion pass. */ | |
2579 | ||
f86b328b | 2580 | namespace { |
2581 | ||
2582 | const pass_data pass_data_lim = | |
2583 | { | |
2584 | GIMPLE_PASS, /* type */ | |
2585 | "lim", /* name */ | |
2586 | OPTGROUP_LOOP, /* optinfo_flags */ | |
f86b328b | 2587 | TV_LIM, /* tv_id */ |
2588 | PROP_cfg, /* properties_required */ | |
2589 | 0, /* properties_provided */ | |
2590 | 0, /* properties_destroyed */ | |
2591 | 0, /* todo_flags_start */ | |
2592 | 0, /* todo_flags_finish */ | |
2593 | }; | |
2594 | ||
2595 | class pass_lim : public gimple_opt_pass | |
2596 | { | |
2597 | public: | |
2598 | pass_lim (gcc::context *ctxt) | |
2599 | : gimple_opt_pass (pass_data_lim, ctxt) | |
2600 | {} | |
2601 | ||
2602 | /* opt_pass methods: */ | |
2603 | opt_pass * clone () { return new pass_lim (m_ctxt); } | |
31315c24 | 2604 | virtual bool gate (function *) { return flag_tree_loop_im != 0; } |
65b0537f | 2605 | virtual unsigned int execute (function *); |
f86b328b | 2606 | |
2607 | }; // class pass_lim | |
2608 | ||
65b0537f | 2609 | unsigned int |
2610 | pass_lim::execute (function *fun) | |
2611 | { | |
2612 | if (number_of_loops (fun) <= 1) | |
2613 | return 0; | |
2614 | ||
2615 | return tree_ssa_lim (); | |
2616 | } | |
2617 | ||
f86b328b | 2618 | } // anon namespace |
2619 | ||
2620 | gimple_opt_pass * | |
2621 | make_pass_lim (gcc::context *ctxt) | |
2622 | { | |
2623 | return new pass_lim (ctxt); | |
2624 | } | |
2625 | ||
2626 |