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7d23383d | 1 | /* Loop invariant motion. |
fbd26352 | 2 | Copyright (C) 2003-2019 Free Software Foundation, Inc. |
48e1416a | 3 | |
7d23383d | 4 | This file is part of GCC. |
48e1416a | 5 | |
7d23383d | 6 | GCC is free software; you can redistribute it and/or modify it |
7 | under the terms of the GNU General Public License as published by the | |
8c4c00c1 | 8 | Free Software Foundation; either version 3, or (at your option) any |
7d23383d | 9 | later version. |
48e1416a | 10 | |
7d23383d | 11 | GCC is distributed in the hope that it will be useful, but WITHOUT |
12 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
48e1416a | 15 | |
7d23383d | 16 | You should have received a copy of the GNU General Public License |
8c4c00c1 | 17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
7d23383d | 19 | |
20 | #include "config.h" | |
21 | #include "system.h" | |
22 | #include "coretypes.h" | |
9ef16211 | 23 | #include "backend.h" |
7d23383d | 24 | #include "tree.h" |
9ef16211 | 25 | #include "gimple.h" |
7c29e30e | 26 | #include "cfghooks.h" |
27 | #include "tree-pass.h" | |
9ef16211 | 28 | #include "ssa.h" |
7c29e30e | 29 | #include "gimple-pretty-print.h" |
b20a8bb4 | 30 | #include "fold-const.h" |
94ea8568 | 31 | #include "cfganal.h" |
bc61cadb | 32 | #include "tree-eh.h" |
a8783bee | 33 | #include "gimplify.h" |
dcf1a1ec | 34 | #include "gimple-iterator.h" |
073c1fd5 | 35 | #include "tree-cfg.h" |
05d9c18a | 36 | #include "tree-ssa-loop-manip.h" |
073c1fd5 | 37 | #include "tree-ssa-loop.h" |
38 | #include "tree-into-ssa.h" | |
7d23383d | 39 | #include "cfgloop.h" |
40 | #include "domwalk.h" | |
41 | #include "params.h" | |
063a8bce | 42 | #include "tree-affine.h" |
a973ed42 | 43 | #include "tree-ssa-propagate.h" |
e797f49f | 44 | #include "trans-mem.h" |
f6a34e3f | 45 | #include "gimple-fold.h" |
b11dc37d | 46 | #include "tree-scalar-evolution.h" |
5b9b62c9 | 47 | #include "tree-ssa-loop-niter.h" |
1b94b295 | 48 | #include "alias.h" |
49 | #include "builtins.h" | |
50 | #include "tree-dfa.h" | |
7d23383d | 51 | |
ca53beb1 | 52 | /* TODO: Support for predicated code motion. I.e. |
53 | ||
54 | while (1) | |
55 | { | |
56 | if (cond) | |
57 | { | |
58 | a = inv; | |
59 | something; | |
60 | } | |
61 | } | |
62 | ||
61025ec0 | 63 | Where COND and INV are invariants, but evaluating INV may trap or be |
ca53beb1 | 64 | invalid from some other reason if !COND. This may be transformed to |
65 | ||
66 | if (cond) | |
67 | a = inv; | |
68 | while (1) | |
69 | { | |
70 | if (cond) | |
71 | something; | |
72 | } */ | |
73 | ||
7d23383d | 74 | /* The auxiliary data kept for each statement. */ |
75 | ||
76 | struct lim_aux_data | |
77 | { | |
2e966e2a | 78 | class loop *max_loop; /* The outermost loop in that the statement |
7d23383d | 79 | is invariant. */ |
80 | ||
2e966e2a | 81 | class loop *tgt_loop; /* The loop out of that we want to move the |
7d23383d | 82 | invariant. */ |
83 | ||
2e966e2a | 84 | class loop *always_executed_in; |
7d23383d | 85 | /* The outermost loop for that we are sure |
86 | the statement is executed if the loop | |
87 | is entered. */ | |
88 | ||
7d23383d | 89 | unsigned cost; /* Cost of the computation performed by the |
90 | statement. */ | |
91 | ||
735d8b51 | 92 | unsigned ref; /* The simple_mem_ref in this stmt or 0. */ |
93 | ||
94 | vec<gimple *> depends; /* Vector of statements that must be also | |
a2c22c0d | 95 | hoisted out of the loop when this statement |
96 | is hoisted; i.e. those that define the | |
97 | operands of the statement and are inside of | |
98 | the MAX_LOOP loop. */ | |
7d23383d | 99 | }; |
100 | ||
75a70cf9 | 101 | /* Maps statements to their lim_aux_data. */ |
102 | ||
42acab1c | 103 | static hash_map<gimple *, lim_aux_data *> *lim_aux_data_map; |
7d23383d | 104 | |
063a8bce | 105 | /* Description of a memory reference location. */ |
7d23383d | 106 | |
4a7ff262 | 107 | struct mem_ref_loc |
7d23383d | 108 | { |
109 | tree *ref; /* The reference itself. */ | |
42acab1c | 110 | gimple *stmt; /* The statement in that it occurs. */ |
4a7ff262 | 111 | }; |
063a8bce | 112 | |
063a8bce | 113 | |
063a8bce | 114 | /* Description of a memory reference. */ |
115 | ||
251317e4 | 116 | class im_mem_ref |
55a03692 | 117 | { |
251317e4 | 118 | public: |
7eae52f1 | 119 | unsigned id : 30; /* ID assigned to the memory reference |
063a8bce | 120 | (its index in memory_accesses.refs_list) */ |
1b94b295 | 121 | unsigned ref_canonical : 1; /* Whether mem.ref was canonicalized. */ |
7eae52f1 | 122 | unsigned ref_decomposed : 1; /* Whether the ref was hashed from mem. */ |
55a03692 | 123 | hashval_t hash; /* Its hash value. */ |
09f4cf62 | 124 | |
125 | /* The memory access itself and associated caching of alias-oracle | |
126 | query meta-data. */ | |
127 | ao_ref mem; | |
128 | ||
3e48928c | 129 | bitmap stored; /* The set of loops in that this memory location |
063a8bce | 130 | is stored to. */ |
3e48928c | 131 | vec<mem_ref_loc> accesses_in_loop; |
063a8bce | 132 | /* The locations of the accesses. Vector |
133 | indexed by the loop number. */ | |
063a8bce | 134 | |
135 | /* The following sets are computed on demand. We keep both set and | |
136 | its complement, so that we know whether the information was | |
137 | already computed or not. */ | |
feba4360 | 138 | bitmap_head indep_loop; /* The set of loops in that the memory |
063a8bce | 139 | reference is independent, meaning: |
140 | If it is stored in the loop, this store | |
141 | is independent on all other loads and | |
142 | stores. | |
143 | If it is only loaded, then it is independent | |
144 | on all stores in the loop. */ | |
feba4360 | 145 | bitmap_head dep_loop; /* The complement of INDEP_LOOP. */ |
4a7ff262 | 146 | }; |
063a8bce | 147 | |
8f9829e8 | 148 | /* We use two bits per loop in the ref->{in,}dep_loop bitmaps, the first |
149 | to record (in)dependence against stores in the loop and its subloops, the | |
150 | second to record (in)dependence against all references in the loop | |
151 | and its subloops. */ | |
152 | #define LOOP_DEP_BIT(loopnum, storedp) (2 * (loopnum) + (storedp ? 1 : 0)) | |
063a8bce | 153 | |
3e871d4d | 154 | /* Mem_ref hashtable helpers. */ |
155 | ||
770ff93b | 156 | struct mem_ref_hasher : nofree_ptr_hash <im_mem_ref> |
3e871d4d | 157 | { |
1b94b295 | 158 | typedef ao_ref *compare_type; |
9969c043 | 159 | static inline hashval_t hash (const im_mem_ref *); |
1b94b295 | 160 | static inline bool equal (const im_mem_ref *, const ao_ref *); |
3e871d4d | 161 | }; |
162 | ||
2e966e2a | 163 | /* A hash function for class im_mem_ref object OBJ. */ |
3e871d4d | 164 | |
165 | inline hashval_t | |
9969c043 | 166 | mem_ref_hasher::hash (const im_mem_ref *mem) |
3e871d4d | 167 | { |
168 | return mem->hash; | |
169 | } | |
170 | ||
2e966e2a | 171 | /* An equality function for class im_mem_ref object MEM1 with |
3e871d4d | 172 | memory reference OBJ2. */ |
173 | ||
174 | inline bool | |
1b94b295 | 175 | mem_ref_hasher::equal (const im_mem_ref *mem1, const ao_ref *obj2) |
176 | { | |
177 | if (obj2->max_size_known_p ()) | |
7eae52f1 | 178 | return (mem1->ref_decomposed |
179 | && operand_equal_p (mem1->mem.base, obj2->base, 0) | |
1b94b295 | 180 | && known_eq (mem1->mem.offset, obj2->offset) |
181 | && known_eq (mem1->mem.size, obj2->size) | |
182 | && known_eq (mem1->mem.max_size, obj2->max_size) | |
183 | && mem1->mem.volatile_p == obj2->volatile_p | |
25971ca0 | 184 | && (mem1->mem.ref_alias_set == obj2->ref_alias_set |
185 | /* We are not canonicalizing alias-sets but for the | |
186 | special-case we didn't canonicalize yet and the | |
187 | incoming ref is a alias-set zero MEM we pick | |
188 | the correct one already. */ | |
189 | || (!mem1->ref_canonical | |
190 | && (TREE_CODE (obj2->ref) == MEM_REF | |
191 | || TREE_CODE (obj2->ref) == TARGET_MEM_REF) | |
192 | && obj2->ref_alias_set == 0) | |
193 | /* Likewise if there's a canonical ref with alias-set zero. */ | |
194 | || (mem1->ref_canonical && mem1->mem.ref_alias_set == 0)) | |
1b94b295 | 195 | && types_compatible_p (TREE_TYPE (mem1->mem.ref), |
196 | TREE_TYPE (obj2->ref))); | |
197 | else | |
198 | return operand_equal_p (mem1->mem.ref, obj2->ref, 0); | |
3e871d4d | 199 | } |
063a8bce | 200 | |
063a8bce | 201 | |
202 | /* Description of memory accesses in loops. */ | |
203 | ||
204 | static struct | |
205 | { | |
206 | /* The hash table of memory references accessed in loops. */ | |
c1f445d2 | 207 | hash_table<mem_ref_hasher> *refs; |
063a8bce | 208 | |
209 | /* The list of memory references. */ | |
4a7ff262 | 210 | vec<im_mem_ref *> refs_list; |
063a8bce | 211 | |
212 | /* The set of memory references accessed in each loop. */ | |
feba4360 | 213 | vec<bitmap_head> refs_in_loop; |
063a8bce | 214 | |
8f9829e8 | 215 | /* The set of memory references stored in each loop. */ |
feba4360 | 216 | vec<bitmap_head> refs_stored_in_loop; |
8f9829e8 | 217 | |
8f9829e8 | 218 | /* The set of memory references stored in each loop, including subloops . */ |
feba4360 | 219 | vec<bitmap_head> all_refs_stored_in_loop; |
063a8bce | 220 | |
221 | /* Cache for expanding memory addresses. */ | |
5f8841a5 | 222 | hash_map<tree, name_expansion *> *ttae_cache; |
063a8bce | 223 | } memory_accesses; |
224 | ||
4fb07d00 | 225 | /* Obstack for the bitmaps in the above data structures. */ |
226 | static bitmap_obstack lim_bitmap_obstack; | |
3e48928c | 227 | static obstack mem_ref_obstack; |
4fb07d00 | 228 | |
2e966e2a | 229 | static bool ref_indep_loop_p (class loop *, im_mem_ref *); |
230 | static bool ref_always_accessed_p (class loop *, im_mem_ref *, bool); | |
7d23383d | 231 | |
232 | /* Minimum cost of an expensive expression. */ | |
233 | #define LIM_EXPENSIVE ((unsigned) PARAM_VALUE (PARAM_LIM_EXPENSIVE)) | |
234 | ||
2fd20c29 | 235 | /* The outermost loop for which execution of the header guarantees that the |
7d23383d | 236 | block will be executed. */ |
2e966e2a | 237 | #define ALWAYS_EXECUTED_IN(BB) ((class loop *) (BB)->aux) |
2fd20c29 | 238 | #define SET_ALWAYS_EXECUTED_IN(BB, VAL) ((BB)->aux = (void *) (VAL)) |
7d23383d | 239 | |
04911505 | 240 | /* ID of the shared unanalyzable mem. */ |
241 | #define UNANALYZABLE_MEM_ID 0 | |
242 | ||
0766b2c0 | 243 | /* Whether the reference was analyzable. */ |
04911505 | 244 | #define MEM_ANALYZABLE(REF) ((REF)->id != UNANALYZABLE_MEM_ID) |
0766b2c0 | 245 | |
75a70cf9 | 246 | static struct lim_aux_data * |
42acab1c | 247 | init_lim_data (gimple *stmt) |
75a70cf9 | 248 | { |
06ecf488 | 249 | lim_aux_data *p = XCNEW (struct lim_aux_data); |
250 | lim_aux_data_map->put (stmt, p); | |
75a70cf9 | 251 | |
06ecf488 | 252 | return p; |
75a70cf9 | 253 | } |
254 | ||
255 | static struct lim_aux_data * | |
42acab1c | 256 | get_lim_data (gimple *stmt) |
75a70cf9 | 257 | { |
06ecf488 | 258 | lim_aux_data **p = lim_aux_data_map->get (stmt); |
75a70cf9 | 259 | if (!p) |
260 | return NULL; | |
261 | ||
06ecf488 | 262 | return *p; |
75a70cf9 | 263 | } |
264 | ||
265 | /* Releases the memory occupied by DATA. */ | |
266 | ||
267 | static void | |
268 | free_lim_aux_data (struct lim_aux_data *data) | |
269 | { | |
9af5ce0c | 270 | data->depends.release (); |
75a70cf9 | 271 | free (data); |
272 | } | |
273 | ||
274 | static void | |
42acab1c | 275 | clear_lim_data (gimple *stmt) |
75a70cf9 | 276 | { |
06ecf488 | 277 | lim_aux_data **p = lim_aux_data_map->get (stmt); |
75a70cf9 | 278 | if (!p) |
279 | return; | |
280 | ||
06ecf488 | 281 | free_lim_aux_data (*p); |
75a70cf9 | 282 | *p = NULL; |
283 | } | |
284 | ||
48e1416a | 285 | |
f86b328b | 286 | /* The possibilities of statement movement. */ |
287 | enum move_pos | |
288 | { | |
289 | MOVE_IMPOSSIBLE, /* No movement -- side effect expression. */ | |
290 | MOVE_PRESERVE_EXECUTION, /* Must not cause the non-executed statement | |
291 | become executed -- memory accesses, ... */ | |
292 | MOVE_POSSIBLE /* Unlimited movement. */ | |
293 | }; | |
aed164c3 | 294 | |
7d23383d | 295 | |
296 | /* If it is possible to hoist the statement STMT unconditionally, | |
297 | returns MOVE_POSSIBLE. | |
298 | If it is possible to hoist the statement STMT, but we must avoid making | |
299 | it executed if it would not be executed in the original program (e.g. | |
300 | because it may trap), return MOVE_PRESERVE_EXECUTION. | |
301 | Otherwise return MOVE_IMPOSSIBLE. */ | |
302 | ||
07c03fb0 | 303 | enum move_pos |
42acab1c | 304 | movement_possibility (gimple *stmt) |
7d23383d | 305 | { |
75a70cf9 | 306 | tree lhs; |
307 | enum move_pos ret = MOVE_POSSIBLE; | |
7d23383d | 308 | |
309 | if (flag_unswitch_loops | |
75a70cf9 | 310 | && gimple_code (stmt) == GIMPLE_COND) |
7d23383d | 311 | { |
312 | /* If we perform unswitching, force the operands of the invariant | |
313 | condition to be moved out of the loop. */ | |
7d23383d | 314 | return MOVE_POSSIBLE; |
315 | } | |
316 | ||
9bf0a3f9 | 317 | if (gimple_code (stmt) == GIMPLE_PHI |
318 | && gimple_phi_num_args (stmt) <= 2 | |
7c782c9b | 319 | && !virtual_operand_p (gimple_phi_result (stmt)) |
9bf0a3f9 | 320 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_phi_result (stmt))) |
321 | return MOVE_POSSIBLE; | |
322 | ||
75a70cf9 | 323 | if (gimple_get_lhs (stmt) == NULL_TREE) |
7d23383d | 324 | return MOVE_IMPOSSIBLE; |
325 | ||
dd277d48 | 326 | if (gimple_vdef (stmt)) |
063a8bce | 327 | return MOVE_IMPOSSIBLE; |
328 | ||
75a70cf9 | 329 | if (stmt_ends_bb_p (stmt) |
330 | || gimple_has_volatile_ops (stmt) | |
331 | || gimple_has_side_effects (stmt) | |
aac19106 | 332 | || stmt_could_throw_p (cfun, stmt)) |
7d23383d | 333 | return MOVE_IMPOSSIBLE; |
334 | ||
75a70cf9 | 335 | if (is_gimple_call (stmt)) |
ca53beb1 | 336 | { |
337 | /* While pure or const call is guaranteed to have no side effects, we | |
338 | cannot move it arbitrarily. Consider code like | |
339 | ||
340 | char *s = something (); | |
341 | ||
342 | while (1) | |
343 | { | |
344 | if (s) | |
345 | t = strlen (s); | |
346 | else | |
347 | t = 0; | |
348 | } | |
349 | ||
350 | Here the strlen call cannot be moved out of the loop, even though | |
351 | s is invariant. In addition to possibly creating a call with | |
352 | invalid arguments, moving out a function call that is not executed | |
353 | may cause performance regressions in case the call is costly and | |
354 | not executed at all. */ | |
75a70cf9 | 355 | ret = MOVE_PRESERVE_EXECUTION; |
356 | lhs = gimple_call_lhs (stmt); | |
ca53beb1 | 357 | } |
75a70cf9 | 358 | else if (is_gimple_assign (stmt)) |
359 | lhs = gimple_assign_lhs (stmt); | |
360 | else | |
361 | return MOVE_IMPOSSIBLE; | |
362 | ||
363 | if (TREE_CODE (lhs) == SSA_NAME | |
364 | && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) | |
365 | return MOVE_IMPOSSIBLE; | |
366 | ||
367 | if (TREE_CODE (lhs) != SSA_NAME | |
368 | || gimple_could_trap_p (stmt)) | |
369 | return MOVE_PRESERVE_EXECUTION; | |
370 | ||
de60f90c | 371 | /* Non local loads in a transaction cannot be hoisted out. Well, |
372 | unless the load happens on every path out of the loop, but we | |
373 | don't take this into account yet. */ | |
374 | if (flag_tm | |
375 | && gimple_in_transaction (stmt) | |
376 | && gimple_assign_single_p (stmt)) | |
377 | { | |
378 | tree rhs = gimple_assign_rhs1 (stmt); | |
379 | if (DECL_P (rhs) && is_global_var (rhs)) | |
380 | { | |
381 | if (dump_file) | |
382 | { | |
383 | fprintf (dump_file, "Cannot hoist conditional load of "); | |
384 | print_generic_expr (dump_file, rhs, TDF_SLIM); | |
385 | fprintf (dump_file, " because it is in a transaction.\n"); | |
386 | } | |
387 | return MOVE_IMPOSSIBLE; | |
388 | } | |
389 | } | |
390 | ||
75a70cf9 | 391 | return ret; |
7d23383d | 392 | } |
393 | ||
394 | /* Suppose that operand DEF is used inside the LOOP. Returns the outermost | |
91275768 | 395 | loop to that we could move the expression using DEF if it did not have |
7d23383d | 396 | other operands, i.e. the outermost loop enclosing LOOP in that the value |
397 | of DEF is invariant. */ | |
398 | ||
2e966e2a | 399 | static class loop * |
400 | outermost_invariant_loop (tree def, class loop *loop) | |
7d23383d | 401 | { |
42acab1c | 402 | gimple *def_stmt; |
7d23383d | 403 | basic_block def_bb; |
2e966e2a | 404 | class loop *max_loop; |
75a70cf9 | 405 | struct lim_aux_data *lim_data; |
7d23383d | 406 | |
75a70cf9 | 407 | if (!def) |
7d23383d | 408 | return superloop_at_depth (loop, 1); |
409 | ||
75a70cf9 | 410 | if (TREE_CODE (def) != SSA_NAME) |
411 | { | |
412 | gcc_assert (is_gimple_min_invariant (def)); | |
413 | return superloop_at_depth (loop, 1); | |
414 | } | |
415 | ||
7d23383d | 416 | def_stmt = SSA_NAME_DEF_STMT (def); |
75a70cf9 | 417 | def_bb = gimple_bb (def_stmt); |
7d23383d | 418 | if (!def_bb) |
419 | return superloop_at_depth (loop, 1); | |
420 | ||
421 | max_loop = find_common_loop (loop, def_bb->loop_father); | |
422 | ||
75a70cf9 | 423 | lim_data = get_lim_data (def_stmt); |
424 | if (lim_data != NULL && lim_data->max_loop != NULL) | |
7d23383d | 425 | max_loop = find_common_loop (max_loop, |
75a70cf9 | 426 | loop_outer (lim_data->max_loop)); |
7d23383d | 427 | if (max_loop == loop) |
428 | return NULL; | |
9e3536f4 | 429 | max_loop = superloop_at_depth (loop, loop_depth (max_loop) + 1); |
7d23383d | 430 | |
431 | return max_loop; | |
432 | } | |
433 | ||
7d23383d | 434 | /* DATA is a structure containing information associated with a statement |
435 | inside LOOP. DEF is one of the operands of this statement. | |
48e1416a | 436 | |
7d23383d | 437 | Find the outermost loop enclosing LOOP in that value of DEF is invariant |
438 | and record this in DATA->max_loop field. If DEF itself is defined inside | |
439 | this loop as well (i.e. we need to hoist it out of the loop if we want | |
440 | to hoist the statement represented by DATA), record the statement in that | |
441 | DEF is defined to the DATA->depends list. Additionally if ADD_COST is true, | |
442 | add the cost of the computation of DEF to the DATA->cost. | |
48e1416a | 443 | |
7d23383d | 444 | If DEF is not invariant in LOOP, return false. Otherwise return TRUE. */ |
445 | ||
446 | static bool | |
2e966e2a | 447 | add_dependency (tree def, struct lim_aux_data *data, class loop *loop, |
7d23383d | 448 | bool add_cost) |
449 | { | |
42acab1c | 450 | gimple *def_stmt = SSA_NAME_DEF_STMT (def); |
75a70cf9 | 451 | basic_block def_bb = gimple_bb (def_stmt); |
2e966e2a | 452 | class loop *max_loop; |
75a70cf9 | 453 | struct lim_aux_data *def_data; |
7d23383d | 454 | |
455 | if (!def_bb) | |
456 | return true; | |
457 | ||
458 | max_loop = outermost_invariant_loop (def, loop); | |
459 | if (!max_loop) | |
460 | return false; | |
461 | ||
462 | if (flow_loop_nested_p (data->max_loop, max_loop)) | |
463 | data->max_loop = max_loop; | |
464 | ||
75a70cf9 | 465 | def_data = get_lim_data (def_stmt); |
466 | if (!def_data) | |
7d23383d | 467 | return true; |
468 | ||
469 | if (add_cost | |
470 | /* Only add the cost if the statement defining DEF is inside LOOP, | |
471 | i.e. if it is likely that by moving the invariants dependent | |
472 | on it, we will be able to avoid creating a new register for | |
473 | it (since it will be only used in these dependent invariants). */ | |
474 | && def_bb->loop_father == loop) | |
75a70cf9 | 475 | data->cost += def_data->cost; |
7d23383d | 476 | |
a2c22c0d | 477 | data->depends.safe_push (def_stmt); |
7d23383d | 478 | |
479 | return true; | |
480 | } | |
481 | ||
0766b2c0 | 482 | /* Returns an estimate for a cost of statement STMT. The values here |
483 | are just ad-hoc constants, similar to costs for inlining. */ | |
7d23383d | 484 | |
485 | static unsigned | |
42acab1c | 486 | stmt_cost (gimple *stmt) |
7d23383d | 487 | { |
7d23383d | 488 | /* Always try to create possibilities for unswitching. */ |
9bf0a3f9 | 489 | if (gimple_code (stmt) == GIMPLE_COND |
490 | || gimple_code (stmt) == GIMPLE_PHI) | |
7d23383d | 491 | return LIM_EXPENSIVE; |
492 | ||
0766b2c0 | 493 | /* We should be hoisting calls if possible. */ |
75a70cf9 | 494 | if (is_gimple_call (stmt)) |
7d23383d | 495 | { |
0766b2c0 | 496 | tree fndecl; |
7d23383d | 497 | |
498 | /* Unless the call is a builtin_constant_p; this always folds to a | |
499 | constant, so moving it is useless. */ | |
75a70cf9 | 500 | fndecl = gimple_call_fndecl (stmt); |
a0e9bfbb | 501 | if (fndecl && fndecl_built_in_p (fndecl, BUILT_IN_CONSTANT_P)) |
7d23383d | 502 | return 0; |
503 | ||
0766b2c0 | 504 | return LIM_EXPENSIVE; |
75a70cf9 | 505 | } |
506 | ||
0766b2c0 | 507 | /* Hoisting memory references out should almost surely be a win. */ |
508 | if (gimple_references_memory_p (stmt)) | |
509 | return LIM_EXPENSIVE; | |
510 | ||
75a70cf9 | 511 | if (gimple_code (stmt) != GIMPLE_ASSIGN) |
0766b2c0 | 512 | return 1; |
7d23383d | 513 | |
75a70cf9 | 514 | switch (gimple_assign_rhs_code (stmt)) |
515 | { | |
7d23383d | 516 | case MULT_EXPR: |
23da77dd | 517 | case WIDEN_MULT_EXPR: |
518 | case WIDEN_MULT_PLUS_EXPR: | |
519 | case WIDEN_MULT_MINUS_EXPR: | |
520 | case DOT_PROD_EXPR: | |
7d23383d | 521 | case TRUNC_DIV_EXPR: |
522 | case CEIL_DIV_EXPR: | |
523 | case FLOOR_DIV_EXPR: | |
524 | case ROUND_DIV_EXPR: | |
525 | case EXACT_DIV_EXPR: | |
526 | case CEIL_MOD_EXPR: | |
527 | case FLOOR_MOD_EXPR: | |
528 | case ROUND_MOD_EXPR: | |
529 | case TRUNC_MOD_EXPR: | |
fd544fc8 | 530 | case RDIV_EXPR: |
7d23383d | 531 | /* Division and multiplication are usually expensive. */ |
0766b2c0 | 532 | return LIM_EXPENSIVE; |
7d23383d | 533 | |
790963ba | 534 | case LSHIFT_EXPR: |
535 | case RSHIFT_EXPR: | |
23da77dd | 536 | case WIDEN_LSHIFT_EXPR: |
537 | case LROTATE_EXPR: | |
538 | case RROTATE_EXPR: | |
0766b2c0 | 539 | /* Shifts and rotates are usually expensive. */ |
540 | return LIM_EXPENSIVE; | |
541 | ||
542 | case CONSTRUCTOR: | |
543 | /* Make vector construction cost proportional to the number | |
544 | of elements. */ | |
545 | return CONSTRUCTOR_NELTS (gimple_assign_rhs1 (stmt)); | |
546 | ||
547 | case SSA_NAME: | |
548 | case PAREN_EXPR: | |
549 | /* Whether or not something is wrapped inside a PAREN_EXPR | |
550 | should not change move cost. Nor should an intermediate | |
551 | unpropagated SSA name copy. */ | |
552 | return 0; | |
790963ba | 553 | |
7d23383d | 554 | default: |
0766b2c0 | 555 | return 1; |
7d23383d | 556 | } |
7d23383d | 557 | } |
558 | ||
063a8bce | 559 | /* Finds the outermost loop between OUTER and LOOP in that the memory reference |
560 | REF is independent. If REF is not independent in LOOP, NULL is returned | |
561 | instead. */ | |
562 | ||
2e966e2a | 563 | static class loop * |
564 | outermost_indep_loop (class loop *outer, class loop *loop, im_mem_ref *ref) | |
063a8bce | 565 | { |
2e966e2a | 566 | class loop *aloop; |
063a8bce | 567 | |
3e48928c | 568 | if (ref->stored && bitmap_bit_p (ref->stored, loop->num)) |
063a8bce | 569 | return NULL; |
570 | ||
571 | for (aloop = outer; | |
572 | aloop != loop; | |
573 | aloop = superloop_at_depth (loop, loop_depth (aloop) + 1)) | |
3e48928c | 574 | if ((!ref->stored || !bitmap_bit_p (ref->stored, aloop->num)) |
23298f15 | 575 | && ref_indep_loop_p (aloop, ref)) |
063a8bce | 576 | return aloop; |
577 | ||
23298f15 | 578 | if (ref_indep_loop_p (loop, ref)) |
063a8bce | 579 | return loop; |
580 | else | |
581 | return NULL; | |
582 | } | |
583 | ||
584 | /* If there is a simple load or store to a memory reference in STMT, returns | |
f0b5f617 | 585 | the location of the memory reference, and sets IS_STORE according to whether |
063a8bce | 586 | it is a store or load. Otherwise, returns NULL. */ |
587 | ||
588 | static tree * | |
42acab1c | 589 | simple_mem_ref_in_stmt (gimple *stmt, bool *is_store) |
063a8bce | 590 | { |
6d7105fe | 591 | tree *lhs, *rhs; |
063a8bce | 592 | |
6d7105fe | 593 | /* Recognize SSA_NAME = MEM and MEM = (SSA_NAME | invariant) patterns. */ |
594 | if (!gimple_assign_single_p (stmt)) | |
063a8bce | 595 | return NULL; |
596 | ||
75a70cf9 | 597 | lhs = gimple_assign_lhs_ptr (stmt); |
6d7105fe | 598 | rhs = gimple_assign_rhs1_ptr (stmt); |
063a8bce | 599 | |
6d7105fe | 600 | if (TREE_CODE (*lhs) == SSA_NAME && gimple_vuse (stmt)) |
063a8bce | 601 | { |
063a8bce | 602 | *is_store = false; |
6d7105fe | 603 | return rhs; |
063a8bce | 604 | } |
6d7105fe | 605 | else if (gimple_vdef (stmt) |
606 | && (TREE_CODE (*rhs) == SSA_NAME || is_gimple_min_invariant (*rhs))) | |
063a8bce | 607 | { |
608 | *is_store = true; | |
609 | return lhs; | |
610 | } | |
611 | else | |
612 | return NULL; | |
613 | } | |
614 | ||
9bf0a3f9 | 615 | /* From a controlling predicate in DOM determine the arguments from |
616 | the PHI node PHI that are chosen if the predicate evaluates to | |
617 | true and false and store them to *TRUE_ARG_P and *FALSE_ARG_P if | |
618 | they are non-NULL. Returns true if the arguments can be determined, | |
619 | else return false. */ | |
620 | ||
621 | static bool | |
1a91d914 | 622 | extract_true_false_args_from_phi (basic_block dom, gphi *phi, |
9bf0a3f9 | 623 | tree *true_arg_p, tree *false_arg_p) |
624 | { | |
df10fba0 | 625 | edge te, fe; |
626 | if (! extract_true_false_controlled_edges (dom, gimple_bb (phi), | |
627 | &te, &fe)) | |
9bf0a3f9 | 628 | return false; |
629 | ||
630 | if (true_arg_p) | |
df10fba0 | 631 | *true_arg_p = PHI_ARG_DEF (phi, te->dest_idx); |
9bf0a3f9 | 632 | if (false_arg_p) |
df10fba0 | 633 | *false_arg_p = PHI_ARG_DEF (phi, fe->dest_idx); |
9bf0a3f9 | 634 | |
635 | return true; | |
636 | } | |
637 | ||
7d23383d | 638 | /* Determine the outermost loop to that it is possible to hoist a statement |
639 | STMT and store it to LIM_DATA (STMT)->max_loop. To do this we determine | |
640 | the outermost loop in that the value computed by STMT is invariant. | |
641 | If MUST_PRESERVE_EXEC is true, additionally choose such a loop that | |
642 | we preserve the fact whether STMT is executed. It also fills other related | |
643 | information to LIM_DATA (STMT). | |
48e1416a | 644 | |
7d23383d | 645 | The function returns false if STMT cannot be hoisted outside of the loop it |
646 | is defined in, and true otherwise. */ | |
647 | ||
648 | static bool | |
42acab1c | 649 | determine_max_movement (gimple *stmt, bool must_preserve_exec) |
7d23383d | 650 | { |
75a70cf9 | 651 | basic_block bb = gimple_bb (stmt); |
2e966e2a | 652 | class loop *loop = bb->loop_father; |
653 | class loop *level; | |
75a70cf9 | 654 | struct lim_aux_data *lim_data = get_lim_data (stmt); |
43daa21e | 655 | tree val; |
656 | ssa_op_iter iter; | |
48e1416a | 657 | |
7d23383d | 658 | if (must_preserve_exec) |
659 | level = ALWAYS_EXECUTED_IN (bb); | |
660 | else | |
661 | level = superloop_at_depth (loop, 1); | |
662 | lim_data->max_loop = level; | |
663 | ||
1a91d914 | 664 | if (gphi *phi = dyn_cast <gphi *> (stmt)) |
9bf0a3f9 | 665 | { |
666 | use_operand_p use_p; | |
667 | unsigned min_cost = UINT_MAX; | |
668 | unsigned total_cost = 0; | |
669 | struct lim_aux_data *def_data; | |
670 | ||
671 | /* We will end up promoting dependencies to be unconditionally | |
672 | evaluated. For this reason the PHI cost (and thus the | |
673 | cost we remove from the loop by doing the invariant motion) | |
674 | is that of the cheapest PHI argument dependency chain. */ | |
1a91d914 | 675 | FOR_EACH_PHI_ARG (use_p, phi, iter, SSA_OP_USE) |
9bf0a3f9 | 676 | { |
677 | val = USE_FROM_PTR (use_p); | |
413fb820 | 678 | |
9bf0a3f9 | 679 | if (TREE_CODE (val) != SSA_NAME) |
413fb820 | 680 | { |
681 | /* Assign const 1 to constants. */ | |
682 | min_cost = MIN (min_cost, 1); | |
683 | total_cost += 1; | |
684 | continue; | |
685 | } | |
9bf0a3f9 | 686 | if (!add_dependency (val, lim_data, loop, false)) |
687 | return false; | |
07f7799f | 688 | |
42acab1c | 689 | gimple *def_stmt = SSA_NAME_DEF_STMT (val); |
07f7799f | 690 | if (gimple_bb (def_stmt) |
691 | && gimple_bb (def_stmt)->loop_father == loop) | |
9bf0a3f9 | 692 | { |
07f7799f | 693 | def_data = get_lim_data (def_stmt); |
694 | if (def_data) | |
695 | { | |
696 | min_cost = MIN (min_cost, def_data->cost); | |
697 | total_cost += def_data->cost; | |
698 | } | |
9bf0a3f9 | 699 | } |
700 | } | |
701 | ||
07f7799f | 702 | min_cost = MIN (min_cost, total_cost); |
9bf0a3f9 | 703 | lim_data->cost += min_cost; |
704 | ||
1a91d914 | 705 | if (gimple_phi_num_args (phi) > 1) |
9bf0a3f9 | 706 | { |
707 | basic_block dom = get_immediate_dominator (CDI_DOMINATORS, bb); | |
42acab1c | 708 | gimple *cond; |
9bf0a3f9 | 709 | if (gsi_end_p (gsi_last_bb (dom))) |
710 | return false; | |
711 | cond = gsi_stmt (gsi_last_bb (dom)); | |
712 | if (gimple_code (cond) != GIMPLE_COND) | |
713 | return false; | |
714 | /* Verify that this is an extended form of a diamond and | |
715 | the PHI arguments are completely controlled by the | |
716 | predicate in DOM. */ | |
1a91d914 | 717 | if (!extract_true_false_args_from_phi (dom, phi, NULL, NULL)) |
9bf0a3f9 | 718 | return false; |
719 | ||
720 | /* Fold in dependencies and cost of the condition. */ | |
721 | FOR_EACH_SSA_TREE_OPERAND (val, cond, iter, SSA_OP_USE) | |
722 | { | |
723 | if (!add_dependency (val, lim_data, loop, false)) | |
724 | return false; | |
725 | def_data = get_lim_data (SSA_NAME_DEF_STMT (val)); | |
726 | if (def_data) | |
47578cb1 | 727 | lim_data->cost += def_data->cost; |
9bf0a3f9 | 728 | } |
729 | ||
730 | /* We want to avoid unconditionally executing very expensive | |
731 | operations. As costs for our dependencies cannot be | |
732 | negative just claim we are not invariand for this case. | |
733 | We also are not sure whether the control-flow inside the | |
734 | loop will vanish. */ | |
735 | if (total_cost - min_cost >= 2 * LIM_EXPENSIVE | |
736 | && !(min_cost != 0 | |
737 | && total_cost / min_cost <= 2)) | |
738 | return false; | |
739 | ||
740 | /* Assume that the control-flow in the loop will vanish. | |
741 | ??? We should verify this and not artificially increase | |
742 | the cost if that is not the case. */ | |
743 | lim_data->cost += stmt_cost (stmt); | |
744 | } | |
745 | ||
746 | return true; | |
747 | } | |
748 | else | |
749 | FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_USE) | |
750 | if (!add_dependency (val, lim_data, loop, true)) | |
751 | return false; | |
7d23383d | 752 | |
dd277d48 | 753 | if (gimple_vuse (stmt)) |
063a8bce | 754 | { |
735d8b51 | 755 | im_mem_ref *ref |
756 | = lim_data ? memory_accesses.refs_list[lim_data->ref] : NULL; | |
757 | if (ref | |
758 | && MEM_ANALYZABLE (ref)) | |
063a8bce | 759 | { |
735d8b51 | 760 | lim_data->max_loop = outermost_indep_loop (lim_data->max_loop, |
761 | loop, ref); | |
063a8bce | 762 | if (!lim_data->max_loop) |
763 | return false; | |
764 | } | |
735d8b51 | 765 | else if (! add_dependency (gimple_vuse (stmt), lim_data, loop, false)) |
766 | return false; | |
063a8bce | 767 | } |
7d23383d | 768 | |
769 | lim_data->cost += stmt_cost (stmt); | |
770 | ||
771 | return true; | |
772 | } | |
773 | ||
774 | /* Suppose that some statement in ORIG_LOOP is hoisted to the loop LEVEL, | |
775 | and that one of the operands of this statement is computed by STMT. | |
776 | Ensure that STMT (together with all the statements that define its | |
777 | operands) is hoisted at least out of the loop LEVEL. */ | |
778 | ||
779 | static void | |
2e966e2a | 780 | set_level (gimple *stmt, class loop *orig_loop, class loop *level) |
7d23383d | 781 | { |
2e966e2a | 782 | class loop *stmt_loop = gimple_bb (stmt)->loop_father; |
75a70cf9 | 783 | struct lim_aux_data *lim_data; |
42acab1c | 784 | gimple *dep_stmt; |
a2c22c0d | 785 | unsigned i; |
7d23383d | 786 | |
787 | stmt_loop = find_common_loop (orig_loop, stmt_loop); | |
75a70cf9 | 788 | lim_data = get_lim_data (stmt); |
789 | if (lim_data != NULL && lim_data->tgt_loop != NULL) | |
7d23383d | 790 | stmt_loop = find_common_loop (stmt_loop, |
75a70cf9 | 791 | loop_outer (lim_data->tgt_loop)); |
7d23383d | 792 | if (flow_loop_nested_p (stmt_loop, level)) |
793 | return; | |
794 | ||
75a70cf9 | 795 | gcc_assert (level == lim_data->max_loop |
796 | || flow_loop_nested_p (lim_data->max_loop, level)); | |
7d23383d | 797 | |
75a70cf9 | 798 | lim_data->tgt_loop = level; |
a2c22c0d | 799 | FOR_EACH_VEC_ELT (lim_data->depends, i, dep_stmt) |
800 | set_level (dep_stmt, orig_loop, level); | |
7d23383d | 801 | } |
802 | ||
803 | /* Determines an outermost loop from that we want to hoist the statement STMT. | |
804 | For now we chose the outermost possible loop. TODO -- use profiling | |
805 | information to set it more sanely. */ | |
806 | ||
807 | static void | |
42acab1c | 808 | set_profitable_level (gimple *stmt) |
7d23383d | 809 | { |
75a70cf9 | 810 | set_level (stmt, gimple_bb (stmt)->loop_father, get_lim_data (stmt)->max_loop); |
7d23383d | 811 | } |
812 | ||
75a70cf9 | 813 | /* Returns true if STMT is a call that has side effects. */ |
7d23383d | 814 | |
815 | static bool | |
42acab1c | 816 | nonpure_call_p (gimple *stmt) |
7d23383d | 817 | { |
75a70cf9 | 818 | if (gimple_code (stmt) != GIMPLE_CALL) |
7d23383d | 819 | return false; |
820 | ||
75a70cf9 | 821 | return gimple_has_side_effects (stmt); |
7d23383d | 822 | } |
823 | ||
790963ba | 824 | /* Rewrite a/b to a*(1/b). Return the invariant stmt to process. */ |
825 | ||
42acab1c | 826 | static gimple * |
75a70cf9 | 827 | rewrite_reciprocal (gimple_stmt_iterator *bsi) |
790963ba | 828 | { |
1a91d914 | 829 | gassign *stmt, *stmt1, *stmt2; |
03d37e4e | 830 | tree name, lhs, type; |
193b8a15 | 831 | tree real_one; |
688ff29b | 832 | gimple_stmt_iterator gsi; |
790963ba | 833 | |
1a91d914 | 834 | stmt = as_a <gassign *> (gsi_stmt (*bsi)); |
75a70cf9 | 835 | lhs = gimple_assign_lhs (stmt); |
836 | type = TREE_TYPE (lhs); | |
790963ba | 837 | |
74560f89 | 838 | real_one = build_one_cst (type); |
790963ba | 839 | |
03d37e4e | 840 | name = make_temp_ssa_name (type, NULL, "reciptmp"); |
e9cf809e | 841 | stmt1 = gimple_build_assign (name, RDIV_EXPR, real_one, |
842 | gimple_assign_rhs2 (stmt)); | |
843 | stmt2 = gimple_build_assign (lhs, MULT_EXPR, name, | |
844 | gimple_assign_rhs1 (stmt)); | |
790963ba | 845 | |
846 | /* Replace division stmt with reciprocal and multiply stmts. | |
847 | The multiply stmt is not invariant, so update iterator | |
848 | and avoid rescanning. */ | |
688ff29b | 849 | gsi = *bsi; |
850 | gsi_insert_before (bsi, stmt1, GSI_NEW_STMT); | |
851 | gsi_replace (&gsi, stmt2, true); | |
790963ba | 852 | |
853 | /* Continue processing with invariant reciprocal statement. */ | |
854 | return stmt1; | |
855 | } | |
856 | ||
857 | /* Check if the pattern at *BSI is a bittest of the form | |
858 | (A >> B) & 1 != 0 and in this case rewrite it to A & (1 << B) != 0. */ | |
859 | ||
42acab1c | 860 | static gimple * |
75a70cf9 | 861 | rewrite_bittest (gimple_stmt_iterator *bsi) |
790963ba | 862 | { |
1a91d914 | 863 | gassign *stmt; |
42acab1c | 864 | gimple *stmt1; |
1a91d914 | 865 | gassign *stmt2; |
42acab1c | 866 | gimple *use_stmt; |
1a91d914 | 867 | gcond *cond_stmt; |
03d37e4e | 868 | tree lhs, name, t, a, b; |
790963ba | 869 | use_operand_p use; |
870 | ||
1a91d914 | 871 | stmt = as_a <gassign *> (gsi_stmt (*bsi)); |
75a70cf9 | 872 | lhs = gimple_assign_lhs (stmt); |
790963ba | 873 | |
874 | /* Verify that the single use of lhs is a comparison against zero. */ | |
875 | if (TREE_CODE (lhs) != SSA_NAME | |
1a91d914 | 876 | || !single_imm_use (lhs, &use, &use_stmt)) |
790963ba | 877 | return stmt; |
1a91d914 | 878 | cond_stmt = dyn_cast <gcond *> (use_stmt); |
879 | if (!cond_stmt) | |
880 | return stmt; | |
881 | if (gimple_cond_lhs (cond_stmt) != lhs | |
882 | || (gimple_cond_code (cond_stmt) != NE_EXPR | |
883 | && gimple_cond_code (cond_stmt) != EQ_EXPR) | |
884 | || !integer_zerop (gimple_cond_rhs (cond_stmt))) | |
790963ba | 885 | return stmt; |
886 | ||
887 | /* Get at the operands of the shift. The rhs is TMP1 & 1. */ | |
75a70cf9 | 888 | stmt1 = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (stmt)); |
889 | if (gimple_code (stmt1) != GIMPLE_ASSIGN) | |
790963ba | 890 | return stmt; |
891 | ||
bef304b8 | 892 | /* There is a conversion in between possibly inserted by fold. */ |
d9659041 | 893 | if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt1))) |
790963ba | 894 | { |
75a70cf9 | 895 | t = gimple_assign_rhs1 (stmt1); |
790963ba | 896 | if (TREE_CODE (t) != SSA_NAME |
897 | || !has_single_use (t)) | |
898 | return stmt; | |
899 | stmt1 = SSA_NAME_DEF_STMT (t); | |
75a70cf9 | 900 | if (gimple_code (stmt1) != GIMPLE_ASSIGN) |
790963ba | 901 | return stmt; |
790963ba | 902 | } |
903 | ||
904 | /* Verify that B is loop invariant but A is not. Verify that with | |
905 | all the stmt walking we are still in the same loop. */ | |
75a70cf9 | 906 | if (gimple_assign_rhs_code (stmt1) != RSHIFT_EXPR |
907 | || loop_containing_stmt (stmt1) != loop_containing_stmt (stmt)) | |
908 | return stmt; | |
790963ba | 909 | |
75a70cf9 | 910 | a = gimple_assign_rhs1 (stmt1); |
911 | b = gimple_assign_rhs2 (stmt1); | |
912 | ||
913 | if (outermost_invariant_loop (b, loop_containing_stmt (stmt1)) != NULL | |
914 | && outermost_invariant_loop (a, loop_containing_stmt (stmt1)) == NULL) | |
915 | { | |
688ff29b | 916 | gimple_stmt_iterator rsi; |
917 | ||
790963ba | 918 | /* 1 << B */ |
790963ba | 919 | t = fold_build2 (LSHIFT_EXPR, TREE_TYPE (a), |
920 | build_int_cst (TREE_TYPE (a), 1), b); | |
03d37e4e | 921 | name = make_temp_ssa_name (TREE_TYPE (a), NULL, "shifttmp"); |
922 | stmt1 = gimple_build_assign (name, t); | |
790963ba | 923 | |
924 | /* A & (1 << B) */ | |
925 | t = fold_build2 (BIT_AND_EXPR, TREE_TYPE (a), a, name); | |
03d37e4e | 926 | name = make_temp_ssa_name (TREE_TYPE (a), NULL, "shifttmp"); |
927 | stmt2 = gimple_build_assign (name, t); | |
3de988b5 | 928 | |
929 | /* Replace the SSA_NAME we compare against zero. Adjust | |
930 | the type of zero accordingly. */ | |
27dc0bdf | 931 | SET_USE (use, name); |
1a91d914 | 932 | gimple_cond_set_rhs (cond_stmt, |
933 | build_int_cst_type (TREE_TYPE (name), | |
934 | 0)); | |
790963ba | 935 | |
688ff29b | 936 | /* Don't use gsi_replace here, none of the new assignments sets |
937 | the variable originally set in stmt. Move bsi to stmt1, and | |
938 | then remove the original stmt, so that we get a chance to | |
939 | retain debug info for it. */ | |
940 | rsi = *bsi; | |
941 | gsi_insert_before (bsi, stmt1, GSI_NEW_STMT); | |
942 | gsi_insert_before (&rsi, stmt2, GSI_SAME_STMT); | |
c7f66ec2 | 943 | gimple *to_release = gsi_stmt (rsi); |
688ff29b | 944 | gsi_remove (&rsi, true); |
c7f66ec2 | 945 | release_defs (to_release); |
790963ba | 946 | |
947 | return stmt1; | |
948 | } | |
949 | ||
950 | return stmt; | |
951 | } | |
952 | ||
54c91640 | 953 | /* For each statement determines the outermost loop in that it is invariant, |
954 | - statements on whose motion it depends and the cost of the computation. | |
955 | - This information is stored to the LIM_DATA structure associated with | |
956 | - each statement. */ | |
957 | class invariantness_dom_walker : public dom_walker | |
958 | { | |
959 | public: | |
960 | invariantness_dom_walker (cdi_direction direction) | |
961 | : dom_walker (direction) {} | |
962 | ||
96752458 | 963 | virtual edge before_dom_children (basic_block); |
54c91640 | 964 | }; |
790963ba | 965 | |
7d23383d | 966 | /* Determine the outermost loops in that statements in basic block BB are |
967 | invariant, and record them to the LIM_DATA associated with the statements. | |
54c91640 | 968 | Callback for dom_walker. */ |
7d23383d | 969 | |
96752458 | 970 | edge |
54c91640 | 971 | invariantness_dom_walker::before_dom_children (basic_block bb) |
7d23383d | 972 | { |
973 | enum move_pos pos; | |
75a70cf9 | 974 | gimple_stmt_iterator bsi; |
42acab1c | 975 | gimple *stmt; |
7d23383d | 976 | bool maybe_never = ALWAYS_EXECUTED_IN (bb) == NULL; |
2e966e2a | 977 | class loop *outermost = ALWAYS_EXECUTED_IN (bb); |
75a70cf9 | 978 | struct lim_aux_data *lim_data; |
7d23383d | 979 | |
9e3536f4 | 980 | if (!loop_outer (bb->loop_father)) |
96752458 | 981 | return NULL; |
7d23383d | 982 | |
983 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
984 | fprintf (dump_file, "Basic block %d (loop %d -- depth %d):\n\n", | |
9e3536f4 | 985 | bb->index, bb->loop_father->num, loop_depth (bb->loop_father)); |
7d23383d | 986 | |
9bf0a3f9 | 987 | /* Look at PHI nodes, but only if there is at most two. |
988 | ??? We could relax this further by post-processing the inserted | |
989 | code and transforming adjacent cond-exprs with the same predicate | |
990 | to control flow again. */ | |
991 | bsi = gsi_start_phis (bb); | |
992 | if (!gsi_end_p (bsi) | |
993 | && ((gsi_next (&bsi), gsi_end_p (bsi)) | |
994 | || (gsi_next (&bsi), gsi_end_p (bsi)))) | |
995 | for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
996 | { | |
997 | stmt = gsi_stmt (bsi); | |
998 | ||
999 | pos = movement_possibility (stmt); | |
1000 | if (pos == MOVE_IMPOSSIBLE) | |
1001 | continue; | |
1002 | ||
735d8b51 | 1003 | lim_data = get_lim_data (stmt); |
1004 | if (! lim_data) | |
1005 | lim_data = init_lim_data (stmt); | |
9bf0a3f9 | 1006 | lim_data->always_executed_in = outermost; |
1007 | ||
1008 | if (!determine_max_movement (stmt, false)) | |
1009 | { | |
1010 | lim_data->max_loop = NULL; | |
1011 | continue; | |
1012 | } | |
1013 | ||
1014 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1015 | { | |
1ffa4346 | 1016 | print_gimple_stmt (dump_file, stmt, 2); |
9bf0a3f9 | 1017 | fprintf (dump_file, " invariant up to level %d, cost %d.\n\n", |
1018 | loop_depth (lim_data->max_loop), | |
1019 | lim_data->cost); | |
1020 | } | |
1021 | ||
1022 | if (lim_data->cost >= LIM_EXPENSIVE) | |
1023 | set_profitable_level (stmt); | |
1024 | } | |
1025 | ||
75a70cf9 | 1026 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
7d23383d | 1027 | { |
75a70cf9 | 1028 | stmt = gsi_stmt (bsi); |
7d23383d | 1029 | |
1030 | pos = movement_possibility (stmt); | |
1031 | if (pos == MOVE_IMPOSSIBLE) | |
1032 | { | |
1033 | if (nonpure_call_p (stmt)) | |
1034 | { | |
1035 | maybe_never = true; | |
1036 | outermost = NULL; | |
1037 | } | |
a973ed42 | 1038 | /* Make sure to note always_executed_in for stores to make |
1039 | store-motion work. */ | |
1040 | else if (stmt_makes_single_store (stmt)) | |
1041 | { | |
735d8b51 | 1042 | struct lim_aux_data *lim_data = get_lim_data (stmt); |
1043 | if (! lim_data) | |
1044 | lim_data = init_lim_data (stmt); | |
75a70cf9 | 1045 | lim_data->always_executed_in = outermost; |
a973ed42 | 1046 | } |
7d23383d | 1047 | continue; |
1048 | } | |
1049 | ||
75a70cf9 | 1050 | if (is_gimple_assign (stmt) |
1051 | && (get_gimple_rhs_class (gimple_assign_rhs_code (stmt)) | |
1052 | == GIMPLE_BINARY_RHS)) | |
63f88450 | 1053 | { |
75a70cf9 | 1054 | tree op0 = gimple_assign_rhs1 (stmt); |
1055 | tree op1 = gimple_assign_rhs2 (stmt); | |
2e966e2a | 1056 | class loop *ol1 = outermost_invariant_loop (op1, |
75a70cf9 | 1057 | loop_containing_stmt (stmt)); |
63f88450 | 1058 | |
1059 | /* If divisor is invariant, convert a/b to a*(1/b), allowing reciprocal | |
1060 | to be hoisted out of loop, saving expensive divide. */ | |
1061 | if (pos == MOVE_POSSIBLE | |
75a70cf9 | 1062 | && gimple_assign_rhs_code (stmt) == RDIV_EXPR |
63f88450 | 1063 | && flag_unsafe_math_optimizations |
1064 | && !flag_trapping_math | |
75a70cf9 | 1065 | && ol1 != NULL |
1066 | && outermost_invariant_loop (op0, ol1) == NULL) | |
63f88450 | 1067 | stmt = rewrite_reciprocal (&bsi); |
1068 | ||
1069 | /* If the shift count is invariant, convert (A >> B) & 1 to | |
1070 | A & (1 << B) allowing the bit mask to be hoisted out of the loop | |
1071 | saving an expensive shift. */ | |
1072 | if (pos == MOVE_POSSIBLE | |
75a70cf9 | 1073 | && gimple_assign_rhs_code (stmt) == BIT_AND_EXPR |
1074 | && integer_onep (op1) | |
1075 | && TREE_CODE (op0) == SSA_NAME | |
1076 | && has_single_use (op0)) | |
63f88450 | 1077 | stmt = rewrite_bittest (&bsi); |
1078 | } | |
fcee97ca | 1079 | |
735d8b51 | 1080 | lim_data = get_lim_data (stmt); |
1081 | if (! lim_data) | |
1082 | lim_data = init_lim_data (stmt); | |
75a70cf9 | 1083 | lim_data->always_executed_in = outermost; |
7d23383d | 1084 | |
1085 | if (maybe_never && pos == MOVE_PRESERVE_EXECUTION) | |
1086 | continue; | |
1087 | ||
1088 | if (!determine_max_movement (stmt, pos == MOVE_PRESERVE_EXECUTION)) | |
1089 | { | |
75a70cf9 | 1090 | lim_data->max_loop = NULL; |
7d23383d | 1091 | continue; |
1092 | } | |
1093 | ||
1094 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1095 | { | |
1ffa4346 | 1096 | print_gimple_stmt (dump_file, stmt, 2); |
7d23383d | 1097 | fprintf (dump_file, " invariant up to level %d, cost %d.\n\n", |
75a70cf9 | 1098 | loop_depth (lim_data->max_loop), |
1099 | lim_data->cost); | |
7d23383d | 1100 | } |
1101 | ||
75a70cf9 | 1102 | if (lim_data->cost >= LIM_EXPENSIVE) |
7d23383d | 1103 | set_profitable_level (stmt); |
1104 | } | |
96752458 | 1105 | return NULL; |
7d23383d | 1106 | } |
1107 | ||
7d23383d | 1108 | /* Hoist the statements in basic block BB out of the loops prescribed by |
91275768 | 1109 | data stored in LIM_DATA structures associated with each statement. Callback |
7d23383d | 1110 | for walk_dominator_tree. */ |
1111 | ||
2c7b2f88 | 1112 | unsigned int |
1113 | move_computations_worker (basic_block bb) | |
7d23383d | 1114 | { |
2e966e2a | 1115 | class loop *level; |
7d23383d | 1116 | unsigned cost = 0; |
75a70cf9 | 1117 | struct lim_aux_data *lim_data; |
2c7b2f88 | 1118 | unsigned int todo = 0; |
7d23383d | 1119 | |
9e3536f4 | 1120 | if (!loop_outer (bb->loop_father)) |
2c7b2f88 | 1121 | return todo; |
7d23383d | 1122 | |
1a91d914 | 1123 | for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); ) |
9bf0a3f9 | 1124 | { |
1a91d914 | 1125 | gassign *new_stmt; |
1126 | gphi *stmt = bsi.phi (); | |
9bf0a3f9 | 1127 | |
1128 | lim_data = get_lim_data (stmt); | |
1129 | if (lim_data == NULL) | |
1130 | { | |
1131 | gsi_next (&bsi); | |
1132 | continue; | |
1133 | } | |
1134 | ||
1135 | cost = lim_data->cost; | |
1136 | level = lim_data->tgt_loop; | |
1137 | clear_lim_data (stmt); | |
1138 | ||
1139 | if (!level) | |
1140 | { | |
1141 | gsi_next (&bsi); | |
1142 | continue; | |
1143 | } | |
1144 | ||
1145 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1146 | { | |
1147 | fprintf (dump_file, "Moving PHI node\n"); | |
1ffa4346 | 1148 | print_gimple_stmt (dump_file, stmt, 0); |
9bf0a3f9 | 1149 | fprintf (dump_file, "(cost %u) out of loop %d.\n\n", |
1150 | cost, level->num); | |
1151 | } | |
1152 | ||
1153 | if (gimple_phi_num_args (stmt) == 1) | |
1154 | { | |
1155 | tree arg = PHI_ARG_DEF (stmt, 0); | |
e9cf809e | 1156 | new_stmt = gimple_build_assign (gimple_phi_result (stmt), |
1157 | TREE_CODE (arg), arg); | |
9bf0a3f9 | 1158 | } |
1159 | else | |
1160 | { | |
1161 | basic_block dom = get_immediate_dominator (CDI_DOMINATORS, bb); | |
42acab1c | 1162 | gimple *cond = gsi_stmt (gsi_last_bb (dom)); |
9bf0a3f9 | 1163 | tree arg0 = NULL_TREE, arg1 = NULL_TREE, t; |
1164 | /* Get the PHI arguments corresponding to the true and false | |
1165 | edges of COND. */ | |
1166 | extract_true_false_args_from_phi (dom, stmt, &arg0, &arg1); | |
1167 | gcc_assert (arg0 && arg1); | |
1168 | t = build2 (gimple_cond_code (cond), boolean_type_node, | |
1169 | gimple_cond_lhs (cond), gimple_cond_rhs (cond)); | |
e9cf809e | 1170 | new_stmt = gimple_build_assign (gimple_phi_result (stmt), |
1171 | COND_EXPR, t, arg0, arg1); | |
2c7b2f88 | 1172 | todo |= TODO_cleanup_cfg; |
9bf0a3f9 | 1173 | } |
8e50a020 | 1174 | if (INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (new_stmt))) |
1175 | && (!ALWAYS_EXECUTED_IN (bb) | |
1176 | || (ALWAYS_EXECUTED_IN (bb) != level | |
1177 | && !flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
ccf6cffa | 1178 | { |
1179 | tree lhs = gimple_assign_lhs (new_stmt); | |
1180 | SSA_NAME_RANGE_INFO (lhs) = NULL; | |
ccf6cffa | 1181 | } |
9bf0a3f9 | 1182 | gsi_insert_on_edge (loop_preheader_edge (level), new_stmt); |
1183 | remove_phi_node (&bsi, false); | |
1184 | } | |
1185 | ||
1a91d914 | 1186 | for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); ) |
7d23383d | 1187 | { |
e70e8b13 | 1188 | edge e; |
1189 | ||
42acab1c | 1190 | gimple *stmt = gsi_stmt (bsi); |
7d23383d | 1191 | |
75a70cf9 | 1192 | lim_data = get_lim_data (stmt); |
1193 | if (lim_data == NULL) | |
7d23383d | 1194 | { |
75a70cf9 | 1195 | gsi_next (&bsi); |
7d23383d | 1196 | continue; |
1197 | } | |
1198 | ||
75a70cf9 | 1199 | cost = lim_data->cost; |
1200 | level = lim_data->tgt_loop; | |
1201 | clear_lim_data (stmt); | |
7d23383d | 1202 | |
1203 | if (!level) | |
1204 | { | |
75a70cf9 | 1205 | gsi_next (&bsi); |
7d23383d | 1206 | continue; |
1207 | } | |
1208 | ||
1209 | /* We do not really want to move conditionals out of the loop; we just | |
1210 | placed it here to force its operands to be moved if necessary. */ | |
75a70cf9 | 1211 | if (gimple_code (stmt) == GIMPLE_COND) |
7d23383d | 1212 | continue; |
1213 | ||
1214 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1215 | { | |
1216 | fprintf (dump_file, "Moving statement\n"); | |
1ffa4346 | 1217 | print_gimple_stmt (dump_file, stmt, 0); |
7d23383d | 1218 | fprintf (dump_file, "(cost %u) out of loop %d.\n\n", |
1219 | cost, level->num); | |
1220 | } | |
063a8bce | 1221 | |
e70e8b13 | 1222 | e = loop_preheader_edge (level); |
1223 | gcc_assert (!gimple_vdef (stmt)); | |
1224 | if (gimple_vuse (stmt)) | |
1225 | { | |
1226 | /* The new VUSE is the one from the virtual PHI in the loop | |
1227 | header or the one already present. */ | |
1a91d914 | 1228 | gphi_iterator gsi2; |
e70e8b13 | 1229 | for (gsi2 = gsi_start_phis (e->dest); |
1230 | !gsi_end_p (gsi2); gsi_next (&gsi2)) | |
1231 | { | |
1a91d914 | 1232 | gphi *phi = gsi2.phi (); |
7c782c9b | 1233 | if (virtual_operand_p (gimple_phi_result (phi))) |
e70e8b13 | 1234 | { |
1235 | gimple_set_vuse (stmt, PHI_ARG_DEF_FROM_EDGE (phi, e)); | |
1236 | break; | |
1237 | } | |
1238 | } | |
1239 | } | |
75a70cf9 | 1240 | gsi_remove (&bsi, false); |
8e50a020 | 1241 | if (gimple_has_lhs (stmt) |
1242 | && TREE_CODE (gimple_get_lhs (stmt)) == SSA_NAME | |
1243 | && INTEGRAL_TYPE_P (TREE_TYPE (gimple_get_lhs (stmt))) | |
1244 | && (!ALWAYS_EXECUTED_IN (bb) | |
1245 | || !(ALWAYS_EXECUTED_IN (bb) == level | |
1246 | || flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
ccf6cffa | 1247 | { |
1248 | tree lhs = gimple_get_lhs (stmt); | |
1249 | SSA_NAME_RANGE_INFO (lhs) = NULL; | |
ccf6cffa | 1250 | } |
bc228ba1 | 1251 | /* In case this is a stmt that is not unconditionally executed |
1252 | when the target loop header is executed and the stmt may | |
1253 | invoke undefined integer or pointer overflow rewrite it to | |
1254 | unsigned arithmetic. */ | |
1255 | if (is_gimple_assign (stmt) | |
1256 | && INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (stmt))) | |
1257 | && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (gimple_assign_lhs (stmt))) | |
1258 | && arith_code_with_undefined_signed_overflow | |
1259 | (gimple_assign_rhs_code (stmt)) | |
1260 | && (!ALWAYS_EXECUTED_IN (bb) | |
1261 | || !(ALWAYS_EXECUTED_IN (bb) == level | |
1262 | || flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
1263 | gsi_insert_seq_on_edge (e, rewrite_to_defined_overflow (stmt)); | |
1264 | else | |
1265 | gsi_insert_on_edge (e, stmt); | |
7d23383d | 1266 | } |
2c7b2f88 | 1267 | |
1268 | return todo; | |
7d23383d | 1269 | } |
1270 | ||
1271 | /* Hoist the statements out of the loops prescribed by data stored in | |
91275768 | 1272 | LIM_DATA structures associated with each statement.*/ |
7d23383d | 1273 | |
9bf0a3f9 | 1274 | static unsigned int |
7d23383d | 1275 | move_computations (void) |
1276 | { | |
2c7b2f88 | 1277 | int *rpo = XNEWVEC (int, last_basic_block_for_fn (cfun)); |
1278 | int n = pre_and_rev_post_order_compute_fn (cfun, NULL, rpo, false); | |
1279 | unsigned todo = 0; | |
1280 | ||
1281 | for (int i = 0; i < n; ++i) | |
1282 | todo |= move_computations_worker (BASIC_BLOCK_FOR_FN (cfun, rpo[i])); | |
1283 | ||
1284 | free (rpo); | |
7d23383d | 1285 | |
75a70cf9 | 1286 | gsi_commit_edge_inserts (); |
dd277d48 | 1287 | if (need_ssa_update_p (cfun)) |
095dcfa3 | 1288 | rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); |
9bf0a3f9 | 1289 | |
2c7b2f88 | 1290 | return todo; |
7d23383d | 1291 | } |
1292 | ||
1293 | /* Checks whether the statement defining variable *INDEX can be hoisted | |
1294 | out of the loop passed in DATA. Callback for for_each_index. */ | |
1295 | ||
1296 | static bool | |
1297 | may_move_till (tree ref, tree *index, void *data) | |
1298 | { | |
2e966e2a | 1299 | class loop *loop = (class loop *) data, *max_loop; |
7d23383d | 1300 | |
1301 | /* If REF is an array reference, check also that the step and the lower | |
1302 | bound is invariant in LOOP. */ | |
1303 | if (TREE_CODE (ref) == ARRAY_REF) | |
1304 | { | |
75a70cf9 | 1305 | tree step = TREE_OPERAND (ref, 3); |
1306 | tree lbound = TREE_OPERAND (ref, 2); | |
7d23383d | 1307 | |
75a70cf9 | 1308 | max_loop = outermost_invariant_loop (step, loop); |
7d23383d | 1309 | if (!max_loop) |
1310 | return false; | |
1311 | ||
75a70cf9 | 1312 | max_loop = outermost_invariant_loop (lbound, loop); |
7d23383d | 1313 | if (!max_loop) |
1314 | return false; | |
1315 | } | |
1316 | ||
1317 | max_loop = outermost_invariant_loop (*index, loop); | |
1318 | if (!max_loop) | |
1319 | return false; | |
1320 | ||
1321 | return true; | |
1322 | } | |
1323 | ||
75a70cf9 | 1324 | /* If OP is SSA NAME, force the statement that defines it to be |
99e96094 | 1325 | moved out of the LOOP. ORIG_LOOP is the loop in that EXPR is used. */ |
7d23383d | 1326 | |
1327 | static void | |
2e966e2a | 1328 | force_move_till_op (tree op, class loop *orig_loop, class loop *loop) |
7d23383d | 1329 | { |
42acab1c | 1330 | gimple *stmt; |
7d23383d | 1331 | |
75a70cf9 | 1332 | if (!op |
1333 | || is_gimple_min_invariant (op)) | |
1334 | return; | |
7d23383d | 1335 | |
75a70cf9 | 1336 | gcc_assert (TREE_CODE (op) == SSA_NAME); |
48e1416a | 1337 | |
75a70cf9 | 1338 | stmt = SSA_NAME_DEF_STMT (op); |
1339 | if (gimple_nop_p (stmt)) | |
7d23383d | 1340 | return; |
1341 | ||
75a70cf9 | 1342 | set_level (stmt, orig_loop, loop); |
7d23383d | 1343 | } |
1344 | ||
1345 | /* Forces statement defining invariants in REF (and *INDEX) to be moved out of | |
99e96094 | 1346 | the LOOP. The reference REF is used in the loop ORIG_LOOP. Callback for |
1347 | for_each_index. */ | |
1348 | ||
1349 | struct fmt_data | |
1350 | { | |
2e966e2a | 1351 | class loop *loop; |
1352 | class loop *orig_loop; | |
99e96094 | 1353 | }; |
7d23383d | 1354 | |
1355 | static bool | |
1356 | force_move_till (tree ref, tree *index, void *data) | |
1357 | { | |
f0d6e81c | 1358 | struct fmt_data *fmt_data = (struct fmt_data *) data; |
7d23383d | 1359 | |
1360 | if (TREE_CODE (ref) == ARRAY_REF) | |
1361 | { | |
75a70cf9 | 1362 | tree step = TREE_OPERAND (ref, 3); |
1363 | tree lbound = TREE_OPERAND (ref, 2); | |
7d23383d | 1364 | |
75a70cf9 | 1365 | force_move_till_op (step, fmt_data->orig_loop, fmt_data->loop); |
1366 | force_move_till_op (lbound, fmt_data->orig_loop, fmt_data->loop); | |
7d23383d | 1367 | } |
1368 | ||
75a70cf9 | 1369 | force_move_till_op (*index, fmt_data->orig_loop, fmt_data->loop); |
7d23383d | 1370 | |
1371 | return true; | |
1372 | } | |
1373 | ||
063a8bce | 1374 | /* A function to free the mem_ref object OBJ. */ |
1375 | ||
1376 | static void | |
2e966e2a | 1377 | memref_free (class im_mem_ref *mem) |
063a8bce | 1378 | { |
f1f41a6c | 1379 | mem->accesses_in_loop.release (); |
063a8bce | 1380 | } |
1381 | ||
1382 | /* Allocates and returns a memory reference description for MEM whose hash | |
1383 | value is HASH and id is ID. */ | |
1384 | ||
4a7ff262 | 1385 | static im_mem_ref * |
1b94b295 | 1386 | mem_ref_alloc (ao_ref *mem, unsigned hash, unsigned id) |
063a8bce | 1387 | { |
2e966e2a | 1388 | im_mem_ref *ref = XOBNEW (&mem_ref_obstack, class im_mem_ref); |
1b94b295 | 1389 | if (mem) |
1390 | ref->mem = *mem; | |
1391 | else | |
1392 | ao_ref_init (&ref->mem, error_mark_node); | |
063a8bce | 1393 | ref->id = id; |
1b94b295 | 1394 | ref->ref_canonical = false; |
7eae52f1 | 1395 | ref->ref_decomposed = false; |
063a8bce | 1396 | ref->hash = hash; |
3e48928c | 1397 | ref->stored = NULL; |
feba4360 | 1398 | bitmap_initialize (&ref->indep_loop, &lim_bitmap_obstack); |
1399 | bitmap_initialize (&ref->dep_loop, &lim_bitmap_obstack); | |
3e48928c | 1400 | ref->accesses_in_loop.create (1); |
063a8bce | 1401 | |
1402 | return ref; | |
1403 | } | |
1404 | ||
063a8bce | 1405 | /* Records memory reference location *LOC in LOOP to the memory reference |
1406 | description REF. The reference occurs in statement STMT. */ | |
7d23383d | 1407 | |
1408 | static void | |
42acab1c | 1409 | record_mem_ref_loc (im_mem_ref *ref, gimple *stmt, tree *loc) |
7d23383d | 1410 | { |
5c8a8be3 | 1411 | mem_ref_loc aref; |
5c8a8be3 | 1412 | aref.stmt = stmt; |
1413 | aref.ref = loc; | |
3e48928c | 1414 | ref->accesses_in_loop.safe_push (aref); |
1415 | } | |
1416 | ||
1417 | /* Set the LOOP bit in REF stored bitmap and allocate that if | |
1418 | necessary. Return whether a bit was changed. */ | |
1419 | ||
1420 | static bool | |
2e966e2a | 1421 | set_ref_stored_in_loop (im_mem_ref *ref, class loop *loop) |
3e48928c | 1422 | { |
1423 | if (!ref->stored) | |
1424 | ref->stored = BITMAP_ALLOC (&lim_bitmap_obstack); | |
1425 | return bitmap_set_bit (ref->stored, loop->num); | |
7d23383d | 1426 | } |
1427 | ||
063a8bce | 1428 | /* Marks reference REF as stored in LOOP. */ |
7d23383d | 1429 | |
1430 | static void | |
2e966e2a | 1431 | mark_ref_stored (im_mem_ref *ref, class loop *loop) |
7d23383d | 1432 | { |
feba4360 | 1433 | while (loop != current_loops->tree_root |
3e48928c | 1434 | && set_ref_stored_in_loop (ref, loop)) |
feba4360 | 1435 | loop = loop_outer (loop); |
063a8bce | 1436 | } |
1437 | ||
1438 | /* Gathers memory references in statement STMT in LOOP, storing the | |
1439 | information about them in the memory_accesses structure. Marks | |
1440 | the vops accessed through unrecognized statements there as | |
1441 | well. */ | |
1442 | ||
1443 | static void | |
2e966e2a | 1444 | gather_mem_refs_stmt (class loop *loop, gimple *stmt) |
063a8bce | 1445 | { |
1446 | tree *mem = NULL; | |
1447 | hashval_t hash; | |
1ada9901 | 1448 | im_mem_ref **slot; |
4a7ff262 | 1449 | im_mem_ref *ref; |
063a8bce | 1450 | bool is_stored; |
063a8bce | 1451 | unsigned id; |
7d23383d | 1452 | |
dd277d48 | 1453 | if (!gimple_vuse (stmt)) |
063a8bce | 1454 | return; |
1455 | ||
1456 | mem = simple_mem_ref_in_stmt (stmt, &is_stored); | |
1457 | if (!mem) | |
0766b2c0 | 1458 | { |
04911505 | 1459 | /* We use the shared mem_ref for all unanalyzable refs. */ |
1460 | id = UNANALYZABLE_MEM_ID; | |
1461 | ref = memory_accesses.refs_list[id]; | |
0766b2c0 | 1462 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1463 | { | |
1464 | fprintf (dump_file, "Unanalyzed memory reference %u: ", id); | |
1465 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1466 | } | |
04911505 | 1467 | is_stored = gimple_vdef (stmt); |
063a8bce | 1468 | } |
1469 | else | |
7d23383d | 1470 | { |
1b94b295 | 1471 | /* We are looking for equal refs that might differ in structure |
1472 | such as a.b vs. MEM[&a + 4]. So we key off the ao_ref but | |
1473 | make sure we can canonicalize the ref in the hashtable if | |
1474 | non-operand_equal_p refs are found. For the lookup we mark | |
1475 | the case we want strict equality with aor.max_size == -1. */ | |
1476 | ao_ref aor; | |
1477 | ao_ref_init (&aor, *mem); | |
1478 | ao_ref_base (&aor); | |
1479 | ao_ref_alias_set (&aor); | |
1480 | HOST_WIDE_INT offset, size, max_size; | |
1481 | poly_int64 saved_maxsize = aor.max_size, mem_off; | |
1482 | tree mem_base; | |
7eae52f1 | 1483 | bool ref_decomposed; |
1b94b295 | 1484 | if (aor.max_size_known_p () |
1485 | && aor.offset.is_constant (&offset) | |
74dbdf38 | 1486 | && aor.size.is_constant (&size) |
1487 | && aor.max_size.is_constant (&max_size) | |
1b94b295 | 1488 | && size == max_size |
74dbdf38 | 1489 | && (size % BITS_PER_UNIT) == 0 |
a657d4f2 | 1490 | /* We're canonicalizing to a MEM where TYPE_SIZE specifies the |
1491 | size. Make sure this is consistent with the extraction. */ | |
1492 | && poly_int_tree_p (TYPE_SIZE (TREE_TYPE (*mem))) | |
1493 | && known_eq (wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (*mem))), | |
1494 | aor.size) | |
1b94b295 | 1495 | && (mem_base = get_addr_base_and_unit_offset (aor.ref, &mem_off))) |
1496 | { | |
7eae52f1 | 1497 | ref_decomposed = true; |
1b94b295 | 1498 | hash = iterative_hash_expr (ao_ref_base (&aor), 0); |
1499 | hash = iterative_hash_host_wide_int (offset, hash); | |
1500 | hash = iterative_hash_host_wide_int (size, hash); | |
1501 | } | |
1502 | else | |
1503 | { | |
7eae52f1 | 1504 | ref_decomposed = false; |
1b94b295 | 1505 | hash = iterative_hash_expr (aor.ref, 0); |
1506 | aor.max_size = -1; | |
1507 | } | |
1508 | slot = memory_accesses.refs->find_slot_with_hash (&aor, hash, INSERT); | |
1509 | aor.max_size = saved_maxsize; | |
04911505 | 1510 | if (*slot) |
063a8bce | 1511 | { |
1b94b295 | 1512 | if (!(*slot)->ref_canonical |
1513 | && !operand_equal_p (*mem, (*slot)->mem.ref, 0)) | |
1514 | { | |
1515 | /* If we didn't yet canonicalize the hashtable ref (which | |
1516 | we'll end up using for code insertion) and hit a second | |
1517 | equal ref that is not structurally equivalent create | |
1518 | a canonical ref which is a bare MEM_REF. */ | |
1519 | if (TREE_CODE (*mem) == MEM_REF | |
1520 | || TREE_CODE (*mem) == TARGET_MEM_REF) | |
1521 | { | |
1522 | (*slot)->mem.ref = *mem; | |
1523 | (*slot)->mem.base_alias_set = ao_ref_base_alias_set (&aor); | |
1524 | } | |
1525 | else | |
1526 | { | |
1527 | tree ref_alias_type = reference_alias_ptr_type (*mem); | |
1528 | unsigned int ref_align = get_object_alignment (*mem); | |
1529 | tree ref_type = TREE_TYPE (*mem); | |
1530 | tree tmp = build_fold_addr_expr (unshare_expr (mem_base)); | |
1531 | if (TYPE_ALIGN (ref_type) != ref_align) | |
1532 | ref_type = build_aligned_type (ref_type, ref_align); | |
1533 | (*slot)->mem.ref | |
1534 | = fold_build2 (MEM_REF, ref_type, tmp, | |
1535 | build_int_cst (ref_alias_type, mem_off)); | |
1536 | if ((*slot)->mem.volatile_p) | |
1537 | TREE_THIS_VOLATILE ((*slot)->mem.ref) = 1; | |
1538 | gcc_checking_assert (TREE_CODE ((*slot)->mem.ref) == MEM_REF | |
1539 | && is_gimple_mem_ref_addr | |
1540 | (TREE_OPERAND ((*slot)->mem.ref, | |
1541 | 0))); | |
1542 | (*slot)->mem.base_alias_set = (*slot)->mem.ref_alias_set; | |
1543 | } | |
1544 | (*slot)->ref_canonical = true; | |
1545 | } | |
4a7ff262 | 1546 | ref = *slot; |
04911505 | 1547 | id = ref->id; |
063a8bce | 1548 | } |
04911505 | 1549 | else |
1550 | { | |
1551 | id = memory_accesses.refs_list.length (); | |
1b94b295 | 1552 | ref = mem_ref_alloc (&aor, hash, id); |
7eae52f1 | 1553 | ref->ref_decomposed = ref_decomposed; |
04911505 | 1554 | memory_accesses.refs_list.safe_push (ref); |
1555 | *slot = ref; | |
61025ec0 | 1556 | |
04911505 | 1557 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1558 | { | |
1559 | fprintf (dump_file, "Memory reference %u: ", id); | |
1560 | print_generic_expr (dump_file, ref->mem.ref, TDF_SLIM); | |
1561 | fprintf (dump_file, "\n"); | |
1562 | } | |
1563 | } | |
1564 | ||
3e48928c | 1565 | record_mem_ref_loc (ref, stmt, mem); |
04911505 | 1566 | } |
feba4360 | 1567 | bitmap_set_bit (&memory_accesses.refs_in_loop[loop->num], ref->id); |
063a8bce | 1568 | if (is_stored) |
8f9829e8 | 1569 | { |
feba4360 | 1570 | bitmap_set_bit (&memory_accesses.refs_stored_in_loop[loop->num], ref->id); |
8f9829e8 | 1571 | mark_ref_stored (ref, loop); |
1572 | } | |
735d8b51 | 1573 | init_lim_data (stmt)->ref = ref->id; |
063a8bce | 1574 | return; |
7d23383d | 1575 | } |
1576 | ||
7894a3d9 | 1577 | static unsigned *bb_loop_postorder; |
1578 | ||
1579 | /* qsort sort function to sort blocks after their loop fathers postorder. */ | |
1580 | ||
1581 | static int | |
0e23c46f | 1582 | sort_bbs_in_loop_postorder_cmp (const void *bb1_, const void *bb2_, |
1583 | void *bb_loop_postorder_) | |
7894a3d9 | 1584 | { |
0e23c46f | 1585 | unsigned *bb_loop_postorder = (unsigned *)bb_loop_postorder_; |
80402f9a | 1586 | basic_block bb1 = *(const basic_block *)bb1_; |
1587 | basic_block bb2 = *(const basic_block *)bb2_; | |
2e966e2a | 1588 | class loop *loop1 = bb1->loop_father; |
1589 | class loop *loop2 = bb2->loop_father; | |
7894a3d9 | 1590 | if (loop1->num == loop2->num) |
2bd42196 | 1591 | return bb1->index - bb2->index; |
7894a3d9 | 1592 | return bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num] ? -1 : 1; |
1593 | } | |
1594 | ||
3e48928c | 1595 | /* qsort sort function to sort ref locs after their loop fathers postorder. */ |
1596 | ||
1597 | static int | |
0e23c46f | 1598 | sort_locs_in_loop_postorder_cmp (const void *loc1_, const void *loc2_, |
1599 | void *bb_loop_postorder_) | |
3e48928c | 1600 | { |
0e23c46f | 1601 | unsigned *bb_loop_postorder = (unsigned *)bb_loop_postorder_; |
80402f9a | 1602 | const mem_ref_loc *loc1 = (const mem_ref_loc *)loc1_; |
1603 | const mem_ref_loc *loc2 = (const mem_ref_loc *)loc2_; | |
2e966e2a | 1604 | class loop *loop1 = gimple_bb (loc1->stmt)->loop_father; |
1605 | class loop *loop2 = gimple_bb (loc2->stmt)->loop_father; | |
3e48928c | 1606 | if (loop1->num == loop2->num) |
1607 | return 0; | |
1608 | return bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num] ? -1 : 1; | |
1609 | } | |
1610 | ||
063a8bce | 1611 | /* Gathers memory references in loops. */ |
7d23383d | 1612 | |
1613 | static void | |
feba4360 | 1614 | analyze_memory_references (void) |
7d23383d | 1615 | { |
75a70cf9 | 1616 | gimple_stmt_iterator bsi; |
7894a3d9 | 1617 | basic_block bb, *bbs; |
2e966e2a | 1618 | class loop *loop, *outer; |
7894a3d9 | 1619 | unsigned i, n; |
063a8bce | 1620 | |
7894a3d9 | 1621 | /* Collect all basic-blocks in loops and sort them after their |
1622 | loops postorder. */ | |
1623 | i = 0; | |
a28770e1 | 1624 | bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS); |
fc00614f | 1625 | FOR_EACH_BB_FN (bb, cfun) |
7894a3d9 | 1626 | if (bb->loop_father != current_loops->tree_root) |
1627 | bbs[i++] = bb; | |
1628 | n = i; | |
0e23c46f | 1629 | gcc_sort_r (bbs, n, sizeof (basic_block), sort_bbs_in_loop_postorder_cmp, |
1630 | bb_loop_postorder); | |
7894a3d9 | 1631 | |
1632 | /* Visit blocks in loop postorder and assign mem-ref IDs in that order. | |
1633 | That results in better locality for all the bitmaps. */ | |
1634 | for (i = 0; i < n; ++i) | |
063a8bce | 1635 | { |
7894a3d9 | 1636 | basic_block bb = bbs[i]; |
75a70cf9 | 1637 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
7894a3d9 | 1638 | gather_mem_refs_stmt (bb->loop_father, gsi_stmt (bsi)); |
063a8bce | 1639 | } |
1640 | ||
3e48928c | 1641 | /* Sort the location list of gathered memory references after their |
1642 | loop postorder number. */ | |
1ada9901 | 1643 | im_mem_ref *ref; |
3e48928c | 1644 | FOR_EACH_VEC_ELT (memory_accesses.refs_list, i, ref) |
0e23c46f | 1645 | ref->accesses_in_loop.sort (sort_locs_in_loop_postorder_cmp, |
1646 | bb_loop_postorder); | |
3e48928c | 1647 | |
7894a3d9 | 1648 | free (bbs); |
1649 | ||
0766b2c0 | 1650 | /* Propagate the information about accessed memory references up |
1651 | the loop hierarchy. */ | |
f21d4d00 | 1652 | FOR_EACH_LOOP (loop, LI_FROM_INNERMOST) |
063a8bce | 1653 | { |
8f9829e8 | 1654 | /* Finalize the overall touched references (including subloops). */ |
feba4360 | 1655 | bitmap_ior_into (&memory_accesses.all_refs_stored_in_loop[loop->num], |
1656 | &memory_accesses.refs_stored_in_loop[loop->num]); | |
8f9829e8 | 1657 | |
1658 | /* Propagate the information about accessed memory references up | |
1659 | the loop hierarchy. */ | |
1660 | outer = loop_outer (loop); | |
1661 | if (outer == current_loops->tree_root) | |
063a8bce | 1662 | continue; |
1663 | ||
feba4360 | 1664 | bitmap_ior_into (&memory_accesses.all_refs_stored_in_loop[outer->num], |
1665 | &memory_accesses.all_refs_stored_in_loop[loop->num]); | |
063a8bce | 1666 | } |
063a8bce | 1667 | } |
1668 | ||
063a8bce | 1669 | /* Returns true if MEM1 and MEM2 may alias. TTAE_CACHE is used as a cache in |
1670 | tree_to_aff_combination_expand. */ | |
1671 | ||
1672 | static bool | |
4a7ff262 | 1673 | mem_refs_may_alias_p (im_mem_ref *mem1, im_mem_ref *mem2, |
5f8841a5 | 1674 | hash_map<tree, name_expansion *> **ttae_cache) |
063a8bce | 1675 | { |
1676 | /* Perform BASE + OFFSET analysis -- if MEM1 and MEM2 are based on the same | |
1677 | object and their offset differ in such a way that the locations cannot | |
1678 | overlap, then they cannot alias. */ | |
fbc666b8 | 1679 | poly_widest_int size1, size2; |
3391cd1e | 1680 | aff_tree off1, off2; |
063a8bce | 1681 | |
3391cd1e | 1682 | /* Perform basic offset and type-based disambiguation. */ |
09f4cf62 | 1683 | if (!refs_may_alias_p_1 (&mem1->mem, &mem2->mem, true)) |
063a8bce | 1684 | return false; |
7d23383d | 1685 | |
063a8bce | 1686 | /* The expansion of addresses may be a bit expensive, thus we only do |
1687 | the check at -O2 and higher optimization levels. */ | |
1688 | if (optimize < 2) | |
1689 | return true; | |
1690 | ||
09f4cf62 | 1691 | get_inner_reference_aff (mem1->mem.ref, &off1, &size1); |
1692 | get_inner_reference_aff (mem2->mem.ref, &off2, &size2); | |
063a8bce | 1693 | aff_combination_expand (&off1, ttae_cache); |
1694 | aff_combination_expand (&off2, ttae_cache); | |
e913b5cd | 1695 | aff_combination_scale (&off1, -1); |
063a8bce | 1696 | aff_combination_add (&off2, &off1); |
1697 | ||
5fc88ffd | 1698 | if (aff_comb_cannot_overlap_p (&off2, size1, size2)) |
063a8bce | 1699 | return false; |
1700 | ||
1701 | return true; | |
1702 | } | |
1703 | ||
3e48928c | 1704 | /* Compare function for bsearch searching for reference locations |
1705 | in a loop. */ | |
1706 | ||
1707 | static int | |
0e23c46f | 1708 | find_ref_loc_in_loop_cmp (const void *loop_, const void *loc_, |
1709 | void *bb_loop_postorder_) | |
3e48928c | 1710 | { |
0e23c46f | 1711 | unsigned *bb_loop_postorder = (unsigned *)bb_loop_postorder_; |
2e966e2a | 1712 | class loop *loop = (class loop *)const_cast<void *>(loop_); |
3e48928c | 1713 | mem_ref_loc *loc = (mem_ref_loc *)const_cast<void *>(loc_); |
2e966e2a | 1714 | class loop *loc_loop = gimple_bb (loc->stmt)->loop_father; |
3e48928c | 1715 | if (loop->num == loc_loop->num |
1716 | || flow_loop_nested_p (loop, loc_loop)) | |
1717 | return 0; | |
1718 | return (bb_loop_postorder[loop->num] < bb_loop_postorder[loc_loop->num] | |
1719 | ? -1 : 1); | |
1720 | } | |
1721 | ||
5c8a8be3 | 1722 | /* Iterates over all locations of REF in LOOP and its subloops calling |
1723 | fn.operator() with the location as argument. When that operator | |
1724 | returns true the iteration is stopped and true is returned. | |
1725 | Otherwise false is returned. */ | |
063a8bce | 1726 | |
5c8a8be3 | 1727 | template <typename FN> |
1728 | static bool | |
2e966e2a | 1729 | for_all_locs_in_loop (class loop *loop, im_mem_ref *ref, FN fn) |
063a8bce | 1730 | { |
063a8bce | 1731 | unsigned i; |
4a7ff262 | 1732 | mem_ref_loc *loc; |
063a8bce | 1733 | |
3e48928c | 1734 | /* Search for the cluster of locs in the accesses_in_loop vector |
1735 | which is sorted after postorder index of the loop father. */ | |
0e23c46f | 1736 | loc = ref->accesses_in_loop.bsearch (loop, find_ref_loc_in_loop_cmp, |
1737 | bb_loop_postorder); | |
3e48928c | 1738 | if (!loc) |
1739 | return false; | |
063a8bce | 1740 | |
3e48928c | 1741 | /* We have found one location inside loop or its sub-loops. Iterate |
1742 | both forward and backward to cover the whole cluster. */ | |
1743 | i = loc - ref->accesses_in_loop.address (); | |
1744 | while (i > 0) | |
1745 | { | |
1746 | --i; | |
4a7ff262 | 1747 | mem_ref_loc *l = &ref->accesses_in_loop[i]; |
3e48928c | 1748 | if (!flow_bb_inside_loop_p (loop, gimple_bb (l->stmt))) |
1749 | break; | |
1750 | if (fn (l)) | |
1751 | return true; | |
1752 | } | |
1753 | for (i = loc - ref->accesses_in_loop.address (); | |
1754 | i < ref->accesses_in_loop.length (); ++i) | |
1755 | { | |
4a7ff262 | 1756 | mem_ref_loc *l = &ref->accesses_in_loop[i]; |
3e48928c | 1757 | if (!flow_bb_inside_loop_p (loop, gimple_bb (l->stmt))) |
1758 | break; | |
1759 | if (fn (l)) | |
1760 | return true; | |
1761 | } | |
5c8a8be3 | 1762 | |
1763 | return false; | |
1764 | } | |
1765 | ||
1766 | /* Rewrites location LOC by TMP_VAR. */ | |
1767 | ||
251317e4 | 1768 | class rewrite_mem_ref_loc |
5c8a8be3 | 1769 | { |
251317e4 | 1770 | public: |
5c8a8be3 | 1771 | rewrite_mem_ref_loc (tree tmp_var_) : tmp_var (tmp_var_) {} |
4a7ff262 | 1772 | bool operator () (mem_ref_loc *loc); |
5c8a8be3 | 1773 | tree tmp_var; |
1774 | }; | |
1775 | ||
1776 | bool | |
4a7ff262 | 1777 | rewrite_mem_ref_loc::operator () (mem_ref_loc *loc) |
5c8a8be3 | 1778 | { |
1779 | *loc->ref = tmp_var; | |
1780 | update_stmt (loc->stmt); | |
1781 | return false; | |
063a8bce | 1782 | } |
1783 | ||
1784 | /* Rewrites all references to REF in LOOP by variable TMP_VAR. */ | |
1785 | ||
1786 | static void | |
2e966e2a | 1787 | rewrite_mem_refs (class loop *loop, im_mem_ref *ref, tree tmp_var) |
063a8bce | 1788 | { |
5c8a8be3 | 1789 | for_all_locs_in_loop (loop, ref, rewrite_mem_ref_loc (tmp_var)); |
7d23383d | 1790 | } |
1791 | ||
bc9af2dd | 1792 | /* Stores the first reference location in LOCP. */ |
1793 | ||
251317e4 | 1794 | class first_mem_ref_loc_1 |
bc9af2dd | 1795 | { |
251317e4 | 1796 | public: |
4a7ff262 | 1797 | first_mem_ref_loc_1 (mem_ref_loc **locp_) : locp (locp_) {} |
1798 | bool operator () (mem_ref_loc *loc); | |
1799 | mem_ref_loc **locp; | |
bc9af2dd | 1800 | }; |
1801 | ||
1802 | bool | |
4a7ff262 | 1803 | first_mem_ref_loc_1::operator () (mem_ref_loc *loc) |
bc9af2dd | 1804 | { |
1805 | *locp = loc; | |
1806 | return true; | |
1807 | } | |
1808 | ||
1809 | /* Returns the first reference location to REF in LOOP. */ | |
1810 | ||
4a7ff262 | 1811 | static mem_ref_loc * |
2e966e2a | 1812 | first_mem_ref_loc (class loop *loop, im_mem_ref *ref) |
bc9af2dd | 1813 | { |
4a7ff262 | 1814 | mem_ref_loc *locp = NULL; |
bc9af2dd | 1815 | for_all_locs_in_loop (loop, ref, first_mem_ref_loc_1 (&locp)); |
1816 | return locp; | |
1817 | } | |
1818 | ||
61025ec0 | 1819 | struct prev_flag_edges { |
1820 | /* Edge to insert new flag comparison code. */ | |
1821 | edge append_cond_position; | |
1822 | ||
1823 | /* Edge for fall through from previous flag comparison. */ | |
1824 | edge last_cond_fallthru; | |
1825 | }; | |
1826 | ||
1827 | /* Helper function for execute_sm. Emit code to store TMP_VAR into | |
1828 | MEM along edge EX. | |
1829 | ||
1830 | The store is only done if MEM has changed. We do this so no | |
1831 | changes to MEM occur on code paths that did not originally store | |
1832 | into it. | |
1833 | ||
1834 | The common case for execute_sm will transform: | |
1835 | ||
1836 | for (...) { | |
1837 | if (foo) | |
1838 | stuff; | |
1839 | else | |
1840 | MEM = TMP_VAR; | |
1841 | } | |
1842 | ||
1843 | into: | |
1844 | ||
1845 | lsm = MEM; | |
1846 | for (...) { | |
1847 | if (foo) | |
1848 | stuff; | |
1849 | else | |
1850 | lsm = TMP_VAR; | |
1851 | } | |
1852 | MEM = lsm; | |
1853 | ||
1854 | This function will generate: | |
1855 | ||
1856 | lsm = MEM; | |
1857 | ||
1858 | lsm_flag = false; | |
1859 | ... | |
1860 | for (...) { | |
1861 | if (foo) | |
1862 | stuff; | |
1863 | else { | |
1864 | lsm = TMP_VAR; | |
1865 | lsm_flag = true; | |
1866 | } | |
1867 | } | |
1868 | if (lsm_flag) <-- | |
1869 | MEM = lsm; <-- | |
1870 | */ | |
1871 | ||
1872 | static void | |
1ea7c812 | 1873 | execute_sm_if_changed (edge ex, tree mem, tree tmp_var, tree flag, |
1874 | edge preheader, hash_set <basic_block> *flag_bbs) | |
61025ec0 | 1875 | { |
1876 | basic_block new_bb, then_bb, old_dest; | |
1877 | bool loop_has_only_one_exit; | |
1878 | edge then_old_edge, orig_ex = ex; | |
1879 | gimple_stmt_iterator gsi; | |
42acab1c | 1880 | gimple *stmt; |
61025ec0 | 1881 | struct prev_flag_edges *prev_edges = (struct prev_flag_edges *) ex->aux; |
a1ccf30d | 1882 | bool irr = ex->flags & EDGE_IRREDUCIBLE_LOOP; |
61025ec0 | 1883 | |
1ea7c812 | 1884 | profile_count count_sum = profile_count::zero (); |
1885 | int nbbs = 0, ncount = 0; | |
720cfc43 | 1886 | profile_probability flag_probability = profile_probability::uninitialized (); |
1ea7c812 | 1887 | |
1888 | /* Flag is set in FLAG_BBS. Determine probability that flag will be true | |
1889 | at loop exit. | |
1890 | ||
f4d3c071 | 1891 | This code may look fancy, but it cannot update profile very realistically |
1ea7c812 | 1892 | because we do not know the probability that flag will be true at given |
1893 | loop exit. | |
1894 | ||
1895 | We look for two interesting extremes | |
1896 | - when exit is dominated by block setting the flag, we know it will | |
1897 | always be true. This is a common case. | |
1898 | - when all blocks setting the flag have very low frequency we know | |
1899 | it will likely be false. | |
1900 | In all other cases we default to 2/3 for flag being true. */ | |
1901 | ||
1902 | for (hash_set<basic_block>::iterator it = flag_bbs->begin (); | |
1903 | it != flag_bbs->end (); ++it) | |
1904 | { | |
1ea7c812 | 1905 | if ((*it)->count.initialized_p ()) |
1906 | count_sum += (*it)->count, ncount ++; | |
1907 | if (dominated_by_p (CDI_DOMINATORS, ex->src, *it)) | |
720cfc43 | 1908 | flag_probability = profile_probability::always (); |
1ea7c812 | 1909 | nbbs++; |
1910 | } | |
1911 | ||
720cfc43 | 1912 | profile_probability cap = profile_probability::always ().apply_scale (2, 3); |
1913 | ||
1914 | if (flag_probability.initialized_p ()) | |
1ea7c812 | 1915 | ; |
205ce1aa | 1916 | else if (ncount == nbbs |
1917 | && preheader->count () >= count_sum && preheader->count ().nonzero_p ()) | |
1ea7c812 | 1918 | { |
ea5d3981 | 1919 | flag_probability = count_sum.probability_in (preheader->count ()); |
720cfc43 | 1920 | if (flag_probability > cap) |
1921 | flag_probability = cap; | |
1ea7c812 | 1922 | } |
205ce1aa | 1923 | |
1924 | if (!flag_probability.initialized_p ()) | |
720cfc43 | 1925 | flag_probability = cap; |
1ea7c812 | 1926 | |
61025ec0 | 1927 | /* ?? Insert store after previous store if applicable. See note |
1928 | below. */ | |
1929 | if (prev_edges) | |
1930 | ex = prev_edges->append_cond_position; | |
1931 | ||
1932 | loop_has_only_one_exit = single_pred_p (ex->dest); | |
1933 | ||
1934 | if (loop_has_only_one_exit) | |
1935 | ex = split_block_after_labels (ex->dest); | |
a1ebf6df | 1936 | else |
1937 | { | |
1938 | for (gphi_iterator gpi = gsi_start_phis (ex->dest); | |
1939 | !gsi_end_p (gpi); gsi_next (&gpi)) | |
1940 | { | |
1941 | gphi *phi = gpi.phi (); | |
1942 | if (virtual_operand_p (gimple_phi_result (phi))) | |
1943 | continue; | |
1944 | ||
1945 | /* When the destination has a non-virtual PHI node with multiple | |
1946 | predecessors make sure we preserve the PHI structure by | |
1947 | forcing a forwarder block so that hoisting of that PHI will | |
1948 | still work. */ | |
1949 | split_edge (ex); | |
1950 | break; | |
1951 | } | |
1952 | } | |
61025ec0 | 1953 | |
1954 | old_dest = ex->dest; | |
1955 | new_bb = split_edge (ex); | |
1956 | then_bb = create_empty_bb (new_bb); | |
1ea7c812 | 1957 | then_bb->count = new_bb->count.apply_probability (flag_probability); |
a1ccf30d | 1958 | if (irr) |
1959 | then_bb->flags = BB_IRREDUCIBLE_LOOP; | |
1960 | add_bb_to_loop (then_bb, new_bb->loop_father); | |
61025ec0 | 1961 | |
1962 | gsi = gsi_start_bb (new_bb); | |
1963 | stmt = gimple_build_cond (NE_EXPR, flag, boolean_false_node, | |
1964 | NULL_TREE, NULL_TREE); | |
1965 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1966 | ||
1967 | gsi = gsi_start_bb (then_bb); | |
1968 | /* Insert actual store. */ | |
1969 | stmt = gimple_build_assign (unshare_expr (mem), tmp_var); | |
1970 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1971 | ||
1ea7c812 | 1972 | edge e1 = single_succ_edge (new_bb); |
1973 | edge e2 = make_edge (new_bb, then_bb, | |
1974 | EDGE_TRUE_VALUE | (irr ? EDGE_IRREDUCIBLE_LOOP : 0)); | |
1975 | e2->probability = flag_probability; | |
1ea7c812 | 1976 | |
1977 | e1->flags |= EDGE_FALSE_VALUE | (irr ? EDGE_IRREDUCIBLE_LOOP : 0); | |
1978 | e1->flags &= ~EDGE_FALLTHRU; | |
1979 | ||
720cfc43 | 1980 | e1->probability = flag_probability.invert (); |
1ea7c812 | 1981 | |
720cfc43 | 1982 | then_old_edge = make_single_succ_edge (then_bb, old_dest, |
a1ccf30d | 1983 | EDGE_FALLTHRU | (irr ? EDGE_IRREDUCIBLE_LOOP : 0)); |
61025ec0 | 1984 | |
1985 | set_immediate_dominator (CDI_DOMINATORS, then_bb, new_bb); | |
1986 | ||
1987 | if (prev_edges) | |
1988 | { | |
1989 | basic_block prevbb = prev_edges->last_cond_fallthru->src; | |
1990 | redirect_edge_succ (prev_edges->last_cond_fallthru, new_bb); | |
1991 | set_immediate_dominator (CDI_DOMINATORS, new_bb, prevbb); | |
1992 | set_immediate_dominator (CDI_DOMINATORS, old_dest, | |
1993 | recompute_dominator (CDI_DOMINATORS, old_dest)); | |
1994 | } | |
1995 | ||
1996 | /* ?? Because stores may alias, they must happen in the exact | |
1997 | sequence they originally happened. Save the position right after | |
1998 | the (_lsm) store we just created so we can continue appending after | |
1999 | it and maintain the original order. */ | |
2000 | { | |
2001 | struct prev_flag_edges *p; | |
2002 | ||
2003 | if (orig_ex->aux) | |
2004 | orig_ex->aux = NULL; | |
2005 | alloc_aux_for_edge (orig_ex, sizeof (struct prev_flag_edges)); | |
2006 | p = (struct prev_flag_edges *) orig_ex->aux; | |
2007 | p->append_cond_position = then_old_edge; | |
2008 | p->last_cond_fallthru = find_edge (new_bb, old_dest); | |
2009 | orig_ex->aux = (void *) p; | |
2010 | } | |
2011 | ||
2012 | if (!loop_has_only_one_exit) | |
1a91d914 | 2013 | for (gphi_iterator gpi = gsi_start_phis (old_dest); |
2014 | !gsi_end_p (gpi); gsi_next (&gpi)) | |
61025ec0 | 2015 | { |
1a91d914 | 2016 | gphi *phi = gpi.phi (); |
61025ec0 | 2017 | unsigned i; |
2018 | ||
2019 | for (i = 0; i < gimple_phi_num_args (phi); i++) | |
2020 | if (gimple_phi_arg_edge (phi, i)->src == new_bb) | |
2021 | { | |
2022 | tree arg = gimple_phi_arg_def (phi, i); | |
60d535d2 | 2023 | add_phi_arg (phi, arg, then_old_edge, UNKNOWN_LOCATION); |
61025ec0 | 2024 | update_stmt (phi); |
2025 | } | |
2026 | } | |
61025ec0 | 2027 | } |
2028 | ||
5c8a8be3 | 2029 | /* When REF is set on the location, set flag indicating the store. */ |
2030 | ||
251317e4 | 2031 | class sm_set_flag_if_changed |
5c8a8be3 | 2032 | { |
251317e4 | 2033 | public: |
1ea7c812 | 2034 | sm_set_flag_if_changed (tree flag_, hash_set <basic_block> *bbs_) |
2035 | : flag (flag_), bbs (bbs_) {} | |
4a7ff262 | 2036 | bool operator () (mem_ref_loc *loc); |
5c8a8be3 | 2037 | tree flag; |
1ea7c812 | 2038 | hash_set <basic_block> *bbs; |
5c8a8be3 | 2039 | }; |
2040 | ||
2041 | bool | |
4a7ff262 | 2042 | sm_set_flag_if_changed::operator () (mem_ref_loc *loc) |
5c8a8be3 | 2043 | { |
2044 | /* Only set the flag for writes. */ | |
2045 | if (is_gimple_assign (loc->stmt) | |
2046 | && gimple_assign_lhs_ptr (loc->stmt) == loc->ref) | |
2047 | { | |
2048 | gimple_stmt_iterator gsi = gsi_for_stmt (loc->stmt); | |
42acab1c | 2049 | gimple *stmt = gimple_build_assign (flag, boolean_true_node); |
5c8a8be3 | 2050 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); |
1ea7c812 | 2051 | bbs->add (gimple_bb (stmt)); |
5c8a8be3 | 2052 | } |
2053 | return false; | |
2054 | } | |
2055 | ||
61025ec0 | 2056 | /* Helper function for execute_sm. On every location where REF is |
2057 | set, set an appropriate flag indicating the store. */ | |
2058 | ||
2059 | static tree | |
2e966e2a | 2060 | execute_sm_if_changed_flag_set (class loop *loop, im_mem_ref *ref, |
1ea7c812 | 2061 | hash_set <basic_block> *bbs) |
61025ec0 | 2062 | { |
61025ec0 | 2063 | tree flag; |
f86b328b | 2064 | char *str = get_lsm_tmp_name (ref->mem.ref, ~0, "_flag"); |
072f7ab1 | 2065 | flag = create_tmp_reg (boolean_type_node, str); |
1ea7c812 | 2066 | for_all_locs_in_loop (loop, ref, sm_set_flag_if_changed (flag, bbs)); |
61025ec0 | 2067 | return flag; |
2068 | } | |
2069 | ||
063a8bce | 2070 | /* Executes store motion of memory reference REF from LOOP. |
749ea85f | 2071 | Exits from the LOOP are stored in EXITS. The initialization of the |
2072 | temporary variable is put to the preheader of the loop, and assignments | |
2073 | to the reference from the temporary variable are emitted to exits. */ | |
7d23383d | 2074 | |
2075 | static void | |
2e966e2a | 2076 | execute_sm (class loop *loop, vec<edge> exits, im_mem_ref *ref) |
7d23383d | 2077 | { |
3e48928c | 2078 | tree tmp_var, store_flag = NULL_TREE; |
7d23383d | 2079 | unsigned i; |
1a91d914 | 2080 | gassign *load; |
99e96094 | 2081 | struct fmt_data fmt_data; |
bc9af2dd | 2082 | edge ex; |
75a70cf9 | 2083 | struct lim_aux_data *lim_data; |
61025ec0 | 2084 | bool multi_threaded_model_p = false; |
bc9af2dd | 2085 | gimple_stmt_iterator gsi; |
1ea7c812 | 2086 | hash_set<basic_block> flag_bbs; |
7d23383d | 2087 | |
69154f26 | 2088 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2089 | { | |
2090 | fprintf (dump_file, "Executing store motion of "); | |
1ffa4346 | 2091 | print_generic_expr (dump_file, ref->mem.ref); |
69154f26 | 2092 | fprintf (dump_file, " from loop %d\n", loop->num); |
2093 | } | |
2094 | ||
09f4cf62 | 2095 | tmp_var = create_tmp_reg (TREE_TYPE (ref->mem.ref), |
2096 | get_lsm_tmp_name (ref->mem.ref, ~0)); | |
7d23383d | 2097 | |
99e96094 | 2098 | fmt_data.loop = loop; |
2099 | fmt_data.orig_loop = loop; | |
09f4cf62 | 2100 | for_each_index (&ref->mem.ref, force_move_till, &fmt_data); |
7d23383d | 2101 | |
c927329e | 2102 | if (bb_in_transaction (loop_preheader_edge (loop)->src) |
60b209bc | 2103 | || (! PARAM_VALUE (PARAM_ALLOW_STORE_DATA_RACES) |
2104 | && ! ref_always_accessed_p (loop, ref, true))) | |
61025ec0 | 2105 | multi_threaded_model_p = true; |
2106 | ||
2107 | if (multi_threaded_model_p) | |
1ea7c812 | 2108 | store_flag = execute_sm_if_changed_flag_set (loop, ref, &flag_bbs); |
61025ec0 | 2109 | |
063a8bce | 2110 | rewrite_mem_refs (loop, ref, tmp_var); |
7d23383d | 2111 | |
bc9af2dd | 2112 | /* Emit the load code on a random exit edge or into the latch if |
2113 | the loop does not exit, so that we are sure it will be processed | |
2114 | by move_computations after all dependencies. */ | |
2115 | gsi = gsi_for_stmt (first_mem_ref_loc (loop, ref)->stmt); | |
61025ec0 | 2116 | |
2117 | /* FIXME/TODO: For the multi-threaded variant, we could avoid this | |
2118 | load altogether, since the store is predicated by a flag. We | |
2119 | could, do the load only if it was originally in the loop. */ | |
09f4cf62 | 2120 | load = gimple_build_assign (tmp_var, unshare_expr (ref->mem.ref)); |
75a70cf9 | 2121 | lim_data = init_lim_data (load); |
2122 | lim_data->max_loop = loop; | |
2123 | lim_data->tgt_loop = loop; | |
bc9af2dd | 2124 | gsi_insert_before (&gsi, load, GSI_SAME_STMT); |
7d23383d | 2125 | |
61025ec0 | 2126 | if (multi_threaded_model_p) |
7d23383d | 2127 | { |
61025ec0 | 2128 | load = gimple_build_assign (store_flag, boolean_false_node); |
2129 | lim_data = init_lim_data (load); | |
2130 | lim_data->max_loop = loop; | |
2131 | lim_data->tgt_loop = loop; | |
bc9af2dd | 2132 | gsi_insert_before (&gsi, load, GSI_SAME_STMT); |
7d23383d | 2133 | } |
61025ec0 | 2134 | |
2135 | /* Sink the store to every exit from the loop. */ | |
f1f41a6c | 2136 | FOR_EACH_VEC_ELT (exits, i, ex) |
61025ec0 | 2137 | if (!multi_threaded_model_p) |
2138 | { | |
1a91d914 | 2139 | gassign *store; |
09f4cf62 | 2140 | store = gimple_build_assign (unshare_expr (ref->mem.ref), tmp_var); |
61025ec0 | 2141 | gsi_insert_on_edge (ex, store); |
2142 | } | |
2143 | else | |
1ea7c812 | 2144 | execute_sm_if_changed (ex, ref->mem.ref, tmp_var, store_flag, |
2145 | loop_preheader_edge (loop), &flag_bbs); | |
7d23383d | 2146 | } |
2147 | ||
063a8bce | 2148 | /* Hoists memory references MEM_REFS out of LOOP. EXITS is the list of exit |
2149 | edges of the LOOP. */ | |
7d23383d | 2150 | |
2151 | static void | |
2e966e2a | 2152 | hoist_memory_references (class loop *loop, bitmap mem_refs, |
f1f41a6c | 2153 | vec<edge> exits) |
7d23383d | 2154 | { |
4a7ff262 | 2155 | im_mem_ref *ref; |
063a8bce | 2156 | unsigned i; |
2157 | bitmap_iterator bi; | |
69154f26 | 2158 | |
063a8bce | 2159 | EXECUTE_IF_SET_IN_BITMAP (mem_refs, 0, i, bi) |
7d23383d | 2160 | { |
f1f41a6c | 2161 | ref = memory_accesses.refs_list[i]; |
063a8bce | 2162 | execute_sm (loop, exits, ref); |
7d23383d | 2163 | } |
55a03692 | 2164 | } |
2165 | ||
251317e4 | 2166 | class ref_always_accessed |
5c8a8be3 | 2167 | { |
251317e4 | 2168 | public: |
2e966e2a | 2169 | ref_always_accessed (class loop *loop_, bool stored_p_) |
3e48928c | 2170 | : loop (loop_), stored_p (stored_p_) {} |
4a7ff262 | 2171 | bool operator () (mem_ref_loc *loc); |
2e966e2a | 2172 | class loop *loop; |
5c8a8be3 | 2173 | bool stored_p; |
2174 | }; | |
7d23383d | 2175 | |
5c8a8be3 | 2176 | bool |
4a7ff262 | 2177 | ref_always_accessed::operator () (mem_ref_loc *loc) |
7d23383d | 2178 | { |
2e966e2a | 2179 | class loop *must_exec; |
307f7fda | 2180 | |
5c8a8be3 | 2181 | if (!get_lim_data (loc->stmt)) |
2182 | return false; | |
7d23383d | 2183 | |
5c8a8be3 | 2184 | /* If we require an always executed store make sure the statement |
2185 | stores to the reference. */ | |
2186 | if (stored_p) | |
063a8bce | 2187 | { |
3e48928c | 2188 | tree lhs = gimple_get_lhs (loc->stmt); |
2189 | if (!lhs | |
2190 | || lhs != *loc->ref) | |
5c8a8be3 | 2191 | return false; |
2192 | } | |
7d23383d | 2193 | |
5c8a8be3 | 2194 | must_exec = get_lim_data (loc->stmt)->always_executed_in; |
2195 | if (!must_exec) | |
2196 | return false; | |
307f7fda | 2197 | |
5c8a8be3 | 2198 | if (must_exec == loop |
2199 | || flow_loop_nested_p (must_exec, loop)) | |
2200 | return true; | |
7d23383d | 2201 | |
5c8a8be3 | 2202 | return false; |
2203 | } | |
55a03692 | 2204 | |
5c8a8be3 | 2205 | /* Returns true if REF is always accessed in LOOP. If STORED_P is true |
2206 | make sure REF is always stored to in LOOP. */ | |
2207 | ||
2208 | static bool | |
2e966e2a | 2209 | ref_always_accessed_p (class loop *loop, im_mem_ref *ref, bool stored_p) |
5c8a8be3 | 2210 | { |
5c8a8be3 | 2211 | return for_all_locs_in_loop (loop, ref, |
3e48928c | 2212 | ref_always_accessed (loop, stored_p)); |
55a03692 | 2213 | } |
2214 | ||
063a8bce | 2215 | /* Returns true if REF1 and REF2 are independent. */ |
55a03692 | 2216 | |
063a8bce | 2217 | static bool |
4a7ff262 | 2218 | refs_independent_p (im_mem_ref *ref1, im_mem_ref *ref2) |
55a03692 | 2219 | { |
09f4cf62 | 2220 | if (ref1 == ref2) |
063a8bce | 2221 | return true; |
09f4cf62 | 2222 | |
063a8bce | 2223 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2224 | fprintf (dump_file, "Querying dependency of refs %u and %u: ", | |
2225 | ref1->id, ref2->id); | |
2226 | ||
09f4cf62 | 2227 | if (mem_refs_may_alias_p (ref1, ref2, &memory_accesses.ttae_cache)) |
063a8bce | 2228 | { |
063a8bce | 2229 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2230 | fprintf (dump_file, "dependent.\n"); | |
2231 | return false; | |
2232 | } | |
2233 | else | |
2234 | { | |
063a8bce | 2235 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2236 | fprintf (dump_file, "independent.\n"); | |
2237 | return true; | |
2238 | } | |
55a03692 | 2239 | } |
2240 | ||
8f9829e8 | 2241 | /* Mark REF dependent on stores or loads (according to STORED_P) in LOOP |
2242 | and its super-loops. */ | |
55a03692 | 2243 | |
2244 | static void | |
2e966e2a | 2245 | record_dep_loop (class loop *loop, im_mem_ref *ref, bool stored_p) |
55a03692 | 2246 | { |
8f9829e8 | 2247 | /* We can propagate dependent-in-loop bits up the loop |
2248 | hierarchy to all outer loops. */ | |
2249 | while (loop != current_loops->tree_root | |
feba4360 | 2250 | && bitmap_set_bit (&ref->dep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
8f9829e8 | 2251 | loop = loop_outer (loop); |
063a8bce | 2252 | } |
55a03692 | 2253 | |
3326faef | 2254 | /* Returns true if REF is independent on all other memory |
23298f15 | 2255 | references in LOOP. */ |
55a03692 | 2256 | |
063a8bce | 2257 | static bool |
2e966e2a | 2258 | ref_indep_loop_p_1 (class loop *loop, im_mem_ref *ref, bool stored_p) |
063a8bce | 2259 | { |
3326faef | 2260 | stored_p |= (ref->stored && bitmap_bit_p (ref->stored, loop->num)); |
2261 | ||
3326faef | 2262 | bool indep_p = true; |
0766b2c0 | 2263 | bitmap refs_to_check; |
063a8bce | 2264 | |
8f9829e8 | 2265 | if (stored_p) |
feba4360 | 2266 | refs_to_check = &memory_accesses.refs_in_loop[loop->num]; |
0766b2c0 | 2267 | else |
feba4360 | 2268 | refs_to_check = &memory_accesses.refs_stored_in_loop[loop->num]; |
55a03692 | 2269 | |
04911505 | 2270 | if (bitmap_bit_p (refs_to_check, UNANALYZABLE_MEM_ID)) |
3326faef | 2271 | indep_p = false; |
3326faef | 2272 | else |
55a03692 | 2273 | { |
3326faef | 2274 | if (bitmap_bit_p (&ref->indep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
2275 | return true; | |
2276 | if (bitmap_bit_p (&ref->dep_loop, LOOP_DEP_BIT (loop->num, stored_p))) | |
8f9829e8 | 2277 | return false; |
55a03692 | 2278 | |
2e966e2a | 2279 | class loop *inner = loop->inner; |
3326faef | 2280 | while (inner) |
2281 | { | |
23298f15 | 2282 | if (!ref_indep_loop_p_1 (inner, ref, stored_p)) |
3326faef | 2283 | { |
2284 | indep_p = false; | |
2285 | break; | |
2286 | } | |
2287 | inner = inner->next; | |
2288 | } | |
f339cf78 | 2289 | |
3326faef | 2290 | if (indep_p) |
2291 | { | |
2292 | unsigned i; | |
2293 | bitmap_iterator bi; | |
2294 | EXECUTE_IF_SET_IN_BITMAP (refs_to_check, 0, i, bi) | |
2295 | { | |
2296 | im_mem_ref *aref = memory_accesses.refs_list[i]; | |
2297 | if (!refs_independent_p (ref, aref)) | |
2298 | { | |
2299 | indep_p = false; | |
2300 | break; | |
2301 | } | |
2302 | } | |
2303 | } | |
8f9829e8 | 2304 | } |
2305 | ||
063a8bce | 2306 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2307 | fprintf (dump_file, "Querying dependencies of ref %u in loop %d: %s\n", | |
8f9829e8 | 2308 | ref->id, loop->num, indep_p ? "independent" : "dependent"); |
063a8bce | 2309 | |
8f9829e8 | 2310 | /* Record the computed result in the cache. */ |
2311 | if (indep_p) | |
2312 | { | |
feba4360 | 2313 | if (bitmap_set_bit (&ref->indep_loop, LOOP_DEP_BIT (loop->num, stored_p)) |
8f9829e8 | 2314 | && stored_p) |
2315 | { | |
2316 | /* If it's independend against all refs then it's independent | |
2317 | against stores, too. */ | |
feba4360 | 2318 | bitmap_set_bit (&ref->indep_loop, LOOP_DEP_BIT (loop->num, false)); |
8f9829e8 | 2319 | } |
2320 | } | |
2321 | else | |
2322 | { | |
2323 | record_dep_loop (loop, ref, stored_p); | |
2324 | if (!stored_p) | |
2325 | { | |
2326 | /* If it's dependent against stores it's dependent against | |
2327 | all refs, too. */ | |
2328 | record_dep_loop (loop, ref, true); | |
2329 | } | |
2330 | } | |
063a8bce | 2331 | |
8f9829e8 | 2332 | return indep_p; |
2333 | } | |
2334 | ||
2335 | /* Returns true if REF is independent on all other memory references in | |
23298f15 | 2336 | LOOP. */ |
8f9829e8 | 2337 | |
2338 | static bool | |
2e966e2a | 2339 | ref_indep_loop_p (class loop *loop, im_mem_ref *ref) |
8f9829e8 | 2340 | { |
2341 | gcc_checking_assert (MEM_ANALYZABLE (ref)); | |
2342 | ||
23298f15 | 2343 | return ref_indep_loop_p_1 (loop, ref, false); |
55a03692 | 2344 | } |
2345 | ||
063a8bce | 2346 | /* Returns true if we can perform store motion of REF from LOOP. */ |
55a03692 | 2347 | |
063a8bce | 2348 | static bool |
2e966e2a | 2349 | can_sm_ref_p (class loop *loop, im_mem_ref *ref) |
55a03692 | 2350 | { |
307f7fda | 2351 | tree base; |
2352 | ||
0766b2c0 | 2353 | /* Can't hoist unanalyzable refs. */ |
2354 | if (!MEM_ANALYZABLE (ref)) | |
2355 | return false; | |
2356 | ||
063a8bce | 2357 | /* It should be movable. */ |
09f4cf62 | 2358 | if (!is_gimple_reg_type (TREE_TYPE (ref->mem.ref)) |
2359 | || TREE_THIS_VOLATILE (ref->mem.ref) | |
2360 | || !for_each_index (&ref->mem.ref, may_move_till, loop)) | |
063a8bce | 2361 | return false; |
342ea212 | 2362 | |
16d9b5d8 | 2363 | /* If it can throw fail, we do not properly update EH info. */ |
09f4cf62 | 2364 | if (tree_could_throw_p (ref->mem.ref)) |
16d9b5d8 | 2365 | return false; |
2366 | ||
307f7fda | 2367 | /* If it can trap, it must be always executed in LOOP. |
2368 | Readonly memory locations may trap when storing to them, but | |
2369 | tree_could_trap_p is a predicate for rvalues, so check that | |
2370 | explicitly. */ | |
09f4cf62 | 2371 | base = get_base_address (ref->mem.ref); |
2372 | if ((tree_could_trap_p (ref->mem.ref) | |
307f7fda | 2373 | || (DECL_P (base) && TREE_READONLY (base))) |
2374 | && !ref_always_accessed_p (loop, ref, true)) | |
063a8bce | 2375 | return false; |
342ea212 | 2376 | |
063a8bce | 2377 | /* And it must be independent on all other memory references |
2378 | in LOOP. */ | |
23298f15 | 2379 | if (!ref_indep_loop_p (loop, ref)) |
063a8bce | 2380 | return false; |
342ea212 | 2381 | |
063a8bce | 2382 | return true; |
342ea212 | 2383 | } |
2384 | ||
063a8bce | 2385 | /* Marks the references in LOOP for that store motion should be performed |
2386 | in REFS_TO_SM. SM_EXECUTED is the set of references for that store | |
2387 | motion was performed in one of the outer loops. */ | |
342ea212 | 2388 | |
2389 | static void | |
2e966e2a | 2390 | find_refs_for_sm (class loop *loop, bitmap sm_executed, bitmap refs_to_sm) |
55a03692 | 2391 | { |
feba4360 | 2392 | bitmap refs = &memory_accesses.all_refs_stored_in_loop[loop->num]; |
063a8bce | 2393 | unsigned i; |
2394 | bitmap_iterator bi; | |
4a7ff262 | 2395 | im_mem_ref *ref; |
063a8bce | 2396 | |
2397 | EXECUTE_IF_AND_COMPL_IN_BITMAP (refs, sm_executed, 0, i, bi) | |
2398 | { | |
f1f41a6c | 2399 | ref = memory_accesses.refs_list[i]; |
063a8bce | 2400 | if (can_sm_ref_p (loop, ref)) |
2401 | bitmap_set_bit (refs_to_sm, i); | |
2402 | } | |
342ea212 | 2403 | } |
55a03692 | 2404 | |
063a8bce | 2405 | /* Checks whether LOOP (with exits stored in EXITS array) is suitable |
2406 | for a store motion optimization (i.e. whether we can insert statement | |
2407 | on its exits). */ | |
342ea212 | 2408 | |
063a8bce | 2409 | static bool |
2e966e2a | 2410 | loop_suitable_for_sm (class loop *loop ATTRIBUTE_UNUSED, |
f1f41a6c | 2411 | vec<edge> exits) |
342ea212 | 2412 | { |
063a8bce | 2413 | unsigned i; |
2414 | edge ex; | |
55a03692 | 2415 | |
f1f41a6c | 2416 | FOR_EACH_VEC_ELT (exits, i, ex) |
9102193b | 2417 | if (ex->flags & (EDGE_ABNORMAL | EDGE_EH)) |
063a8bce | 2418 | return false; |
2419 | ||
2420 | return true; | |
55a03692 | 2421 | } |
2422 | ||
7d23383d | 2423 | /* Try to perform store motion for all memory references modified inside |
063a8bce | 2424 | LOOP. SM_EXECUTED is the bitmap of the memory references for that |
2425 | store motion was executed in one of the outer loops. */ | |
7d23383d | 2426 | |
2427 | static void | |
2e966e2a | 2428 | store_motion_loop (class loop *loop, bitmap sm_executed) |
7d23383d | 2429 | { |
f1f41a6c | 2430 | vec<edge> exits = get_loop_exit_edges (loop); |
2e966e2a | 2431 | class loop *subloop; |
39f8afdf | 2432 | bitmap sm_in_loop = BITMAP_ALLOC (&lim_bitmap_obstack); |
7d23383d | 2433 | |
063a8bce | 2434 | if (loop_suitable_for_sm (loop, exits)) |
7d23383d | 2435 | { |
063a8bce | 2436 | find_refs_for_sm (loop, sm_executed, sm_in_loop); |
2437 | hoist_memory_references (loop, sm_in_loop, exits); | |
7d23383d | 2438 | } |
f1f41a6c | 2439 | exits.release (); |
063a8bce | 2440 | |
2441 | bitmap_ior_into (sm_executed, sm_in_loop); | |
2442 | for (subloop = loop->inner; subloop != NULL; subloop = subloop->next) | |
2443 | store_motion_loop (subloop, sm_executed); | |
2444 | bitmap_and_compl_into (sm_executed, sm_in_loop); | |
2445 | BITMAP_FREE (sm_in_loop); | |
7d23383d | 2446 | } |
2447 | ||
2448 | /* Try to perform store motion for all memory references modified inside | |
7194de72 | 2449 | loops. */ |
7d23383d | 2450 | |
2451 | static void | |
063a8bce | 2452 | store_motion (void) |
7d23383d | 2453 | { |
2e966e2a | 2454 | class loop *loop; |
39f8afdf | 2455 | bitmap sm_executed = BITMAP_ALLOC (&lim_bitmap_obstack); |
dda28f7c | 2456 | |
063a8bce | 2457 | for (loop = current_loops->tree_root->inner; loop != NULL; loop = loop->next) |
2458 | store_motion_loop (loop, sm_executed); | |
17519ba0 | 2459 | |
063a8bce | 2460 | BITMAP_FREE (sm_executed); |
75a70cf9 | 2461 | gsi_commit_edge_inserts (); |
7d23383d | 2462 | } |
2463 | ||
2464 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks of LOOP, i.e. | |
2465 | for each such basic block bb records the outermost loop for that execution | |
2466 | of its header implies execution of bb. CONTAINS_CALL is the bitmap of | |
2467 | blocks that contain a nonpure call. */ | |
2468 | ||
2469 | static void | |
2e966e2a | 2470 | fill_always_executed_in_1 (class loop *loop, sbitmap contains_call) |
7d23383d | 2471 | { |
2472 | basic_block bb = NULL, *bbs, last = NULL; | |
2473 | unsigned i; | |
2474 | edge e; | |
2e966e2a | 2475 | class loop *inn_loop = loop; |
7d23383d | 2476 | |
2fd20c29 | 2477 | if (ALWAYS_EXECUTED_IN (loop->header) == NULL) |
7d23383d | 2478 | { |
2479 | bbs = get_loop_body_in_dom_order (loop); | |
2480 | ||
2481 | for (i = 0; i < loop->num_nodes; i++) | |
2482 | { | |
cd665a06 | 2483 | edge_iterator ei; |
7d23383d | 2484 | bb = bbs[i]; |
2485 | ||
2486 | if (dominated_by_p (CDI_DOMINATORS, loop->latch, bb)) | |
2487 | last = bb; | |
2488 | ||
08b7917c | 2489 | if (bitmap_bit_p (contains_call, bb->index)) |
7d23383d | 2490 | break; |
2491 | ||
cd665a06 | 2492 | FOR_EACH_EDGE (e, ei, bb->succs) |
5b9b62c9 | 2493 | { |
2494 | /* If there is an exit from this BB. */ | |
2495 | if (!flow_bb_inside_loop_p (loop, e->dest)) | |
2496 | break; | |
2497 | /* Or we enter a possibly non-finite loop. */ | |
2498 | if (flow_loop_nested_p (bb->loop_father, | |
2499 | e->dest->loop_father) | |
2500 | && ! finite_loop_p (e->dest->loop_father)) | |
2501 | break; | |
2502 | } | |
7d23383d | 2503 | if (e) |
2504 | break; | |
2505 | ||
2506 | /* A loop might be infinite (TODO use simple loop analysis | |
2507 | to disprove this if possible). */ | |
2508 | if (bb->flags & BB_IRREDUCIBLE_LOOP) | |
2509 | break; | |
2510 | ||
2511 | if (!flow_bb_inside_loop_p (inn_loop, bb)) | |
2512 | break; | |
2513 | ||
2514 | if (bb->loop_father->header == bb) | |
2515 | { | |
2516 | if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb)) | |
2517 | break; | |
2518 | ||
2519 | /* In a loop that is always entered we may proceed anyway. | |
2520 | But record that we entered it and stop once we leave it. */ | |
2521 | inn_loop = bb->loop_father; | |
2522 | } | |
2523 | } | |
2524 | ||
2525 | while (1) | |
2526 | { | |
2fd20c29 | 2527 | SET_ALWAYS_EXECUTED_IN (last, loop); |
7d23383d | 2528 | if (last == loop->header) |
2529 | break; | |
2530 | last = get_immediate_dominator (CDI_DOMINATORS, last); | |
2531 | } | |
2532 | ||
2533 | free (bbs); | |
2534 | } | |
2535 | ||
2536 | for (loop = loop->inner; loop; loop = loop->next) | |
feba4360 | 2537 | fill_always_executed_in_1 (loop, contains_call); |
7d23383d | 2538 | } |
2539 | ||
feba4360 | 2540 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks, i.e. |
2541 | for each such basic block bb records the outermost loop for that execution | |
2542 | of its header implies execution of bb. */ | |
7d23383d | 2543 | |
2544 | static void | |
feba4360 | 2545 | fill_always_executed_in (void) |
7d23383d | 2546 | { |
7d23383d | 2547 | basic_block bb; |
2e966e2a | 2548 | class loop *loop; |
4fb07d00 | 2549 | |
3c6549f8 | 2550 | auto_sbitmap contains_call (last_basic_block_for_fn (cfun)); |
53c5d9d4 | 2551 | bitmap_clear (contains_call); |
fc00614f | 2552 | FOR_EACH_BB_FN (bb, cfun) |
7d23383d | 2553 | { |
feba4360 | 2554 | gimple_stmt_iterator gsi; |
2555 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
7d23383d | 2556 | { |
feba4360 | 2557 | if (nonpure_call_p (gsi_stmt (gsi))) |
7d23383d | 2558 | break; |
2559 | } | |
2560 | ||
feba4360 | 2561 | if (!gsi_end_p (gsi)) |
08b7917c | 2562 | bitmap_set_bit (contains_call, bb->index); |
7d23383d | 2563 | } |
2564 | ||
7194de72 | 2565 | for (loop = current_loops->tree_root->inner; loop; loop = loop->next) |
feba4360 | 2566 | fill_always_executed_in_1 (loop, contains_call); |
feba4360 | 2567 | } |
2568 | ||
2569 | ||
2570 | /* Compute the global information needed by the loop invariant motion pass. */ | |
75a70cf9 | 2571 | |
feba4360 | 2572 | static void |
2573 | tree_ssa_lim_initialize (void) | |
2574 | { | |
2e966e2a | 2575 | class loop *loop; |
feba4360 | 2576 | unsigned i; |
2577 | ||
2578 | bitmap_obstack_initialize (&lim_bitmap_obstack); | |
3e48928c | 2579 | gcc_obstack_init (&mem_ref_obstack); |
42acab1c | 2580 | lim_aux_data_map = new hash_map<gimple *, lim_aux_data *>; |
de60f90c | 2581 | |
2582 | if (flag_tm) | |
2583 | compute_transaction_bits (); | |
61025ec0 | 2584 | |
2585 | alloc_aux_for_edges (0); | |
feba4360 | 2586 | |
c1f445d2 | 2587 | memory_accesses.refs = new hash_table<mem_ref_hasher> (100); |
feba4360 | 2588 | memory_accesses.refs_list.create (100); |
2589 | /* Allocate a special, unanalyzable mem-ref with ID zero. */ | |
2590 | memory_accesses.refs_list.quick_push | |
1b94b295 | 2591 | (mem_ref_alloc (NULL, 0, UNANALYZABLE_MEM_ID)); |
feba4360 | 2592 | |
41f75a99 | 2593 | memory_accesses.refs_in_loop.create (number_of_loops (cfun)); |
2594 | memory_accesses.refs_in_loop.quick_grow (number_of_loops (cfun)); | |
2595 | memory_accesses.refs_stored_in_loop.create (number_of_loops (cfun)); | |
2596 | memory_accesses.refs_stored_in_loop.quick_grow (number_of_loops (cfun)); | |
2597 | memory_accesses.all_refs_stored_in_loop.create (number_of_loops (cfun)); | |
2598 | memory_accesses.all_refs_stored_in_loop.quick_grow (number_of_loops (cfun)); | |
feba4360 | 2599 | |
41f75a99 | 2600 | for (i = 0; i < number_of_loops (cfun); i++) |
feba4360 | 2601 | { |
2602 | bitmap_initialize (&memory_accesses.refs_in_loop[i], | |
2603 | &lim_bitmap_obstack); | |
2604 | bitmap_initialize (&memory_accesses.refs_stored_in_loop[i], | |
2605 | &lim_bitmap_obstack); | |
2606 | bitmap_initialize (&memory_accesses.all_refs_stored_in_loop[i], | |
2607 | &lim_bitmap_obstack); | |
2608 | } | |
2609 | ||
2610 | memory_accesses.ttae_cache = NULL; | |
3e48928c | 2611 | |
2612 | /* Initialize bb_loop_postorder with a mapping from loop->num to | |
2613 | its postorder index. */ | |
2614 | i = 0; | |
2615 | bb_loop_postorder = XNEWVEC (unsigned, number_of_loops (cfun)); | |
2616 | FOR_EACH_LOOP (loop, LI_FROM_INNERMOST) | |
2617 | bb_loop_postorder[loop->num] = i++; | |
7d23383d | 2618 | } |
2619 | ||
2620 | /* Cleans up after the invariant motion pass. */ | |
2621 | ||
2622 | static void | |
2623 | tree_ssa_lim_finalize (void) | |
2624 | { | |
2625 | basic_block bb; | |
063a8bce | 2626 | unsigned i; |
4a7ff262 | 2627 | im_mem_ref *ref; |
7d23383d | 2628 | |
61025ec0 | 2629 | free_aux_for_edges (); |
2630 | ||
fc00614f | 2631 | FOR_EACH_BB_FN (bb, cfun) |
2fd20c29 | 2632 | SET_ALWAYS_EXECUTED_IN (bb, NULL); |
063a8bce | 2633 | |
4fb07d00 | 2634 | bitmap_obstack_release (&lim_bitmap_obstack); |
06ecf488 | 2635 | delete lim_aux_data_map; |
75a70cf9 | 2636 | |
c1f445d2 | 2637 | delete memory_accesses.refs; |
2638 | memory_accesses.refs = NULL; | |
063a8bce | 2639 | |
f1f41a6c | 2640 | FOR_EACH_VEC_ELT (memory_accesses.refs_list, i, ref) |
83b709f2 | 2641 | memref_free (ref); |
f1f41a6c | 2642 | memory_accesses.refs_list.release (); |
3e48928c | 2643 | obstack_free (&mem_ref_obstack, NULL); |
83b709f2 | 2644 | |
f1f41a6c | 2645 | memory_accesses.refs_in_loop.release (); |
8f9829e8 | 2646 | memory_accesses.refs_stored_in_loop.release (); |
f1f41a6c | 2647 | memory_accesses.all_refs_stored_in_loop.release (); |
063a8bce | 2648 | |
2649 | if (memory_accesses.ttae_cache) | |
78d53e33 | 2650 | free_affine_expand_cache (&memory_accesses.ttae_cache); |
3e48928c | 2651 | |
2652 | free (bb_loop_postorder); | |
7d23383d | 2653 | } |
2654 | ||
7194de72 | 2655 | /* Moves invariants from loops. Only "expensive" invariants are moved out -- |
7d23383d | 2656 | i.e. those that are likely to be win regardless of the register pressure. */ |
2657 | ||
b11dc37d | 2658 | static unsigned int |
7194de72 | 2659 | tree_ssa_lim (void) |
7d23383d | 2660 | { |
9bf0a3f9 | 2661 | unsigned int todo; |
2662 | ||
7194de72 | 2663 | tree_ssa_lim_initialize (); |
7d23383d | 2664 | |
063a8bce | 2665 | /* Gathers information about memory accesses in the loops. */ |
2666 | analyze_memory_references (); | |
2667 | ||
feba4360 | 2668 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks. */ |
2669 | fill_always_executed_in (); | |
2670 | ||
7d23383d | 2671 | /* For each statement determine the outermost loop in that it is |
2672 | invariant and cost for computing the invariant. */ | |
54c91640 | 2673 | invariantness_dom_walker (CDI_DOMINATORS) |
2674 | .walk (cfun->cfg->x_entry_block_ptr); | |
7d23383d | 2675 | |
063a8bce | 2676 | /* Execute store motion. Force the necessary invariants to be moved |
2677 | out of the loops as well. */ | |
2678 | store_motion (); | |
7d23383d | 2679 | |
2680 | /* Move the expressions that are expensive enough. */ | |
9bf0a3f9 | 2681 | todo = move_computations (); |
7d23383d | 2682 | |
2683 | tree_ssa_lim_finalize (); | |
9bf0a3f9 | 2684 | |
2685 | return todo; | |
7d23383d | 2686 | } |
f86b328b | 2687 | |
2688 | /* Loop invariant motion pass. */ | |
2689 | ||
f86b328b | 2690 | namespace { |
2691 | ||
2692 | const pass_data pass_data_lim = | |
2693 | { | |
2694 | GIMPLE_PASS, /* type */ | |
2695 | "lim", /* name */ | |
2696 | OPTGROUP_LOOP, /* optinfo_flags */ | |
f86b328b | 2697 | TV_LIM, /* tv_id */ |
2698 | PROP_cfg, /* properties_required */ | |
2699 | 0, /* properties_provided */ | |
2700 | 0, /* properties_destroyed */ | |
2701 | 0, /* todo_flags_start */ | |
2702 | 0, /* todo_flags_finish */ | |
2703 | }; | |
2704 | ||
2705 | class pass_lim : public gimple_opt_pass | |
2706 | { | |
2707 | public: | |
2708 | pass_lim (gcc::context *ctxt) | |
2709 | : gimple_opt_pass (pass_data_lim, ctxt) | |
2710 | {} | |
2711 | ||
2712 | /* opt_pass methods: */ | |
2713 | opt_pass * clone () { return new pass_lim (m_ctxt); } | |
31315c24 | 2714 | virtual bool gate (function *) { return flag_tree_loop_im != 0; } |
65b0537f | 2715 | virtual unsigned int execute (function *); |
f86b328b | 2716 | |
2717 | }; // class pass_lim | |
2718 | ||
65b0537f | 2719 | unsigned int |
2720 | pass_lim::execute (function *fun) | |
2721 | { | |
b11dc37d | 2722 | bool in_loop_pipeline = scev_initialized_p (); |
2723 | if (!in_loop_pipeline) | |
2724 | loop_optimizer_init (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS); | |
2725 | ||
65b0537f | 2726 | if (number_of_loops (fun) <= 1) |
2727 | return 0; | |
b11dc37d | 2728 | unsigned int todo = tree_ssa_lim (); |
65b0537f | 2729 | |
b11dc37d | 2730 | if (!in_loop_pipeline) |
2731 | loop_optimizer_finalize (); | |
9b33fe18 | 2732 | else |
2733 | scev_reset (); | |
b11dc37d | 2734 | return todo; |
65b0537f | 2735 | } |
2736 | ||
f86b328b | 2737 | } // anon namespace |
2738 | ||
2739 | gimple_opt_pass * | |
2740 | make_pass_lim (gcc::context *ctxt) | |
2741 | { | |
2742 | return new pass_lim (ctxt); | |
2743 | } | |
2744 | ||
2745 |