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a7e5372d | 1 | /* Loop invariant motion. |
8d9254fc | 2 | Copyright (C) 2003-2020 Free Software Foundation, Inc. |
b8698a0f | 3 | |
a7e5372d | 4 | This file is part of GCC. |
b8698a0f | 5 | |
a7e5372d ZD |
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 | |
9dcd6f09 | 8 | Free Software Foundation; either version 3, or (at your option) any |
a7e5372d | 9 | later version. |
b8698a0f | 10 | |
a7e5372d ZD |
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. | |
b8698a0f | 15 | |
a7e5372d | 16 | You should have received a copy of the GNU General Public License |
9dcd6f09 NC |
17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
a7e5372d ZD |
19 | |
20 | #include "config.h" | |
21 | #include "system.h" | |
22 | #include "coretypes.h" | |
c7131fb2 | 23 | #include "backend.h" |
a7e5372d | 24 | #include "tree.h" |
c7131fb2 | 25 | #include "gimple.h" |
957060b5 AM |
26 | #include "cfghooks.h" |
27 | #include "tree-pass.h" | |
c7131fb2 | 28 | #include "ssa.h" |
957060b5 | 29 | #include "gimple-pretty-print.h" |
40e23961 | 30 | #include "fold-const.h" |
60393bbc | 31 | #include "cfganal.h" |
2fb9a547 | 32 | #include "tree-eh.h" |
45b0be94 | 33 | #include "gimplify.h" |
5be5c238 | 34 | #include "gimple-iterator.h" |
442b4905 | 35 | #include "tree-cfg.h" |
e28030cf | 36 | #include "tree-ssa-loop-manip.h" |
442b4905 AM |
37 | #include "tree-ssa-loop.h" |
38 | #include "tree-into-ssa.h" | |
a7e5372d ZD |
39 | #include "cfgloop.h" |
40 | #include "domwalk.h" | |
72425608 | 41 | #include "tree-affine.h" |
8ded35f9 | 42 | #include "tree-ssa-propagate.h" |
1fe37220 | 43 | #include "trans-mem.h" |
19e51b40 | 44 | #include "gimple-fold.h" |
9c37629f | 45 | #include "tree-scalar-evolution.h" |
964ef24c | 46 | #include "tree-ssa-loop-niter.h" |
1c852d1d RB |
47 | #include "alias.h" |
48 | #include "builtins.h" | |
49 | #include "tree-dfa.h" | |
a7e5372d | 50 | |
f10a6654 ZD |
51 | /* TODO: Support for predicated code motion. I.e. |
52 | ||
53 | while (1) | |
54 | { | |
55 | if (cond) | |
56 | { | |
57 | a = inv; | |
58 | something; | |
59 | } | |
60 | } | |
61 | ||
039496da | 62 | Where COND and INV are invariants, but evaluating INV may trap or be |
f10a6654 ZD |
63 | invalid from some other reason if !COND. This may be transformed to |
64 | ||
65 | if (cond) | |
66 | a = inv; | |
67 | while (1) | |
68 | { | |
69 | if (cond) | |
70 | something; | |
71 | } */ | |
72 | ||
a7e5372d ZD |
73 | /* The auxiliary data kept for each statement. */ |
74 | ||
75 | struct lim_aux_data | |
76 | { | |
99b1c316 | 77 | class loop *max_loop; /* The outermost loop in that the statement |
a7e5372d ZD |
78 | is invariant. */ |
79 | ||
99b1c316 | 80 | class loop *tgt_loop; /* The loop out of that we want to move the |
a7e5372d ZD |
81 | invariant. */ |
82 | ||
99b1c316 | 83 | class loop *always_executed_in; |
a7e5372d ZD |
84 | /* The outermost loop for that we are sure |
85 | the statement is executed if the loop | |
86 | is entered. */ | |
87 | ||
a7e5372d ZD |
88 | unsigned cost; /* Cost of the computation performed by the |
89 | statement. */ | |
90 | ||
5164293a RB |
91 | unsigned ref; /* The simple_mem_ref in this stmt or 0. */ |
92 | ||
93 | vec<gimple *> depends; /* Vector of statements that must be also | |
76421b44 RB |
94 | hoisted out of the loop when this statement |
95 | is hoisted; i.e. those that define the | |
96 | operands of the statement and are inside of | |
97 | the MAX_LOOP loop. */ | |
a7e5372d ZD |
98 | }; |
99 | ||
726a989a RB |
100 | /* Maps statements to their lim_aux_data. */ |
101 | ||
355fe088 | 102 | static hash_map<gimple *, lim_aux_data *> *lim_aux_data_map; |
a7e5372d | 103 | |
72425608 | 104 | /* Description of a memory reference location. */ |
a7e5372d | 105 | |
61baec41 | 106 | struct mem_ref_loc |
a7e5372d ZD |
107 | { |
108 | tree *ref; /* The reference itself. */ | |
355fe088 | 109 | gimple *stmt; /* The statement in that it occurs. */ |
61baec41 | 110 | }; |
72425608 | 111 | |
72425608 | 112 | |
72425608 ZD |
113 | /* Description of a memory reference. */ |
114 | ||
6c1dae73 | 115 | class im_mem_ref |
01fd257a | 116 | { |
6c1dae73 | 117 | public: |
a8aa828b | 118 | unsigned id : 30; /* ID assigned to the memory reference |
72425608 | 119 | (its index in memory_accesses.refs_list) */ |
1c852d1d | 120 | unsigned ref_canonical : 1; /* Whether mem.ref was canonicalized. */ |
a8aa828b | 121 | unsigned ref_decomposed : 1; /* Whether the ref was hashed from mem. */ |
01fd257a | 122 | hashval_t hash; /* Its hash value. */ |
bdb01696 RB |
123 | |
124 | /* The memory access itself and associated caching of alias-oracle | |
125 | query meta-data. */ | |
126 | ao_ref mem; | |
127 | ||
32500433 | 128 | bitmap stored; /* The set of loops in that this memory location |
72425608 | 129 | is stored to. */ |
32500433 | 130 | vec<mem_ref_loc> accesses_in_loop; |
72425608 ZD |
131 | /* The locations of the accesses. Vector |
132 | indexed by the loop number. */ | |
72425608 ZD |
133 | |
134 | /* The following sets are computed on demand. We keep both set and | |
135 | its complement, so that we know whether the information was | |
136 | already computed or not. */ | |
374001cb | 137 | bitmap_head indep_loop; /* The set of loops in that the memory |
72425608 ZD |
138 | reference is independent, meaning: |
139 | If it is stored in the loop, this store | |
140 | is independent on all other loads and | |
141 | stores. | |
142 | If it is only loaded, then it is independent | |
143 | on all stores in the loop. */ | |
374001cb | 144 | bitmap_head dep_loop; /* The complement of INDEP_LOOP. */ |
61baec41 | 145 | }; |
72425608 | 146 | |
c00217fc RB |
147 | /* We use two bits per loop in the ref->{in,}dep_loop bitmaps, the first |
148 | to record (in)dependence against stores in the loop and its subloops, the | |
149 | second to record (in)dependence against all references in the loop | |
150 | and its subloops. */ | |
151 | #define LOOP_DEP_BIT(loopnum, storedp) (2 * (loopnum) + (storedp ? 1 : 0)) | |
72425608 | 152 | |
bf190e8d LC |
153 | /* Mem_ref hashtable helpers. */ |
154 | ||
8d67ee55 | 155 | struct mem_ref_hasher : nofree_ptr_hash <im_mem_ref> |
bf190e8d | 156 | { |
1c852d1d | 157 | typedef ao_ref *compare_type; |
67f58944 | 158 | static inline hashval_t hash (const im_mem_ref *); |
1c852d1d | 159 | static inline bool equal (const im_mem_ref *, const ao_ref *); |
bf190e8d LC |
160 | }; |
161 | ||
99b1c316 | 162 | /* A hash function for class im_mem_ref object OBJ. */ |
bf190e8d LC |
163 | |
164 | inline hashval_t | |
67f58944 | 165 | mem_ref_hasher::hash (const im_mem_ref *mem) |
bf190e8d LC |
166 | { |
167 | return mem->hash; | |
168 | } | |
169 | ||
99b1c316 | 170 | /* An equality function for class im_mem_ref object MEM1 with |
bf190e8d LC |
171 | memory reference OBJ2. */ |
172 | ||
173 | inline bool | |
1c852d1d RB |
174 | mem_ref_hasher::equal (const im_mem_ref *mem1, const ao_ref *obj2) |
175 | { | |
176 | if (obj2->max_size_known_p ()) | |
a8aa828b RB |
177 | return (mem1->ref_decomposed |
178 | && operand_equal_p (mem1->mem.base, obj2->base, 0) | |
1c852d1d RB |
179 | && known_eq (mem1->mem.offset, obj2->offset) |
180 | && known_eq (mem1->mem.size, obj2->size) | |
181 | && known_eq (mem1->mem.max_size, obj2->max_size) | |
182 | && mem1->mem.volatile_p == obj2->volatile_p | |
8c996ec6 RB |
183 | && (mem1->mem.ref_alias_set == obj2->ref_alias_set |
184 | /* We are not canonicalizing alias-sets but for the | |
185 | special-case we didn't canonicalize yet and the | |
186 | incoming ref is a alias-set zero MEM we pick | |
187 | the correct one already. */ | |
188 | || (!mem1->ref_canonical | |
189 | && (TREE_CODE (obj2->ref) == MEM_REF | |
190 | || TREE_CODE (obj2->ref) == TARGET_MEM_REF) | |
191 | && obj2->ref_alias_set == 0) | |
192 | /* Likewise if there's a canonical ref with alias-set zero. */ | |
193 | || (mem1->ref_canonical && mem1->mem.ref_alias_set == 0)) | |
1c852d1d RB |
194 | && types_compatible_p (TREE_TYPE (mem1->mem.ref), |
195 | TREE_TYPE (obj2->ref))); | |
196 | else | |
197 | return operand_equal_p (mem1->mem.ref, obj2->ref, 0); | |
bf190e8d | 198 | } |
72425608 | 199 | |
72425608 ZD |
200 | |
201 | /* Description of memory accesses in loops. */ | |
202 | ||
203 | static struct | |
204 | { | |
205 | /* The hash table of memory references accessed in loops. */ | |
c203e8a7 | 206 | hash_table<mem_ref_hasher> *refs; |
72425608 ZD |
207 | |
208 | /* The list of memory references. */ | |
61baec41 | 209 | vec<im_mem_ref *> refs_list; |
72425608 ZD |
210 | |
211 | /* The set of memory references accessed in each loop. */ | |
374001cb | 212 | vec<bitmap_head> refs_in_loop; |
72425608 | 213 | |
c00217fc | 214 | /* The set of memory references stored in each loop. */ |
374001cb | 215 | vec<bitmap_head> refs_stored_in_loop; |
c00217fc | 216 | |
c00217fc | 217 | /* The set of memory references stored in each loop, including subloops . */ |
374001cb | 218 | vec<bitmap_head> all_refs_stored_in_loop; |
72425608 ZD |
219 | |
220 | /* Cache for expanding memory addresses. */ | |
39c8aaa4 | 221 | hash_map<tree, name_expansion *> *ttae_cache; |
72425608 ZD |
222 | } memory_accesses; |
223 | ||
3f9b14ff SB |
224 | /* Obstack for the bitmaps in the above data structures. */ |
225 | static bitmap_obstack lim_bitmap_obstack; | |
32500433 | 226 | static obstack mem_ref_obstack; |
3f9b14ff | 227 | |
99b1c316 MS |
228 | static bool ref_indep_loop_p (class loop *, im_mem_ref *); |
229 | static bool ref_always_accessed_p (class loop *, im_mem_ref *, bool); | |
a7e5372d ZD |
230 | |
231 | /* Minimum cost of an expensive expression. */ | |
028d4092 | 232 | #define LIM_EXPENSIVE ((unsigned) param_lim_expensive) |
a7e5372d | 233 | |
8a519095 | 234 | /* The outermost loop for which execution of the header guarantees that the |
a7e5372d | 235 | block will be executed. */ |
99b1c316 | 236 | #define ALWAYS_EXECUTED_IN(BB) ((class loop *) (BB)->aux) |
8a519095 | 237 | #define SET_ALWAYS_EXECUTED_IN(BB, VAL) ((BB)->aux = (void *) (VAL)) |
a7e5372d | 238 | |
e6647190 RB |
239 | /* ID of the shared unanalyzable mem. */ |
240 | #define UNANALYZABLE_MEM_ID 0 | |
241 | ||
546d314c | 242 | /* Whether the reference was analyzable. */ |
e6647190 | 243 | #define MEM_ANALYZABLE(REF) ((REF)->id != UNANALYZABLE_MEM_ID) |
546d314c | 244 | |
726a989a | 245 | static struct lim_aux_data * |
355fe088 | 246 | init_lim_data (gimple *stmt) |
726a989a | 247 | { |
b787e7a2 TS |
248 | lim_aux_data *p = XCNEW (struct lim_aux_data); |
249 | lim_aux_data_map->put (stmt, p); | |
726a989a | 250 | |
b787e7a2 | 251 | return p; |
726a989a RB |
252 | } |
253 | ||
254 | static struct lim_aux_data * | |
355fe088 | 255 | get_lim_data (gimple *stmt) |
726a989a | 256 | { |
b787e7a2 | 257 | lim_aux_data **p = lim_aux_data_map->get (stmt); |
726a989a RB |
258 | if (!p) |
259 | return NULL; | |
260 | ||
b787e7a2 | 261 | return *p; |
726a989a RB |
262 | } |
263 | ||
264 | /* Releases the memory occupied by DATA. */ | |
265 | ||
266 | static void | |
267 | free_lim_aux_data (struct lim_aux_data *data) | |
268 | { | |
c3284718 | 269 | data->depends.release (); |
726a989a RB |
270 | free (data); |
271 | } | |
272 | ||
273 | static void | |
355fe088 | 274 | clear_lim_data (gimple *stmt) |
726a989a | 275 | { |
b787e7a2 | 276 | lim_aux_data **p = lim_aux_data_map->get (stmt); |
726a989a RB |
277 | if (!p) |
278 | return; | |
279 | ||
b787e7a2 | 280 | free_lim_aux_data (*p); |
726a989a RB |
281 | *p = NULL; |
282 | } | |
283 | ||
b8698a0f | 284 | |
71343877 AM |
285 | /* The possibilities of statement movement. */ |
286 | enum move_pos | |
287 | { | |
288 | MOVE_IMPOSSIBLE, /* No movement -- side effect expression. */ | |
289 | MOVE_PRESERVE_EXECUTION, /* Must not cause the non-executed statement | |
290 | become executed -- memory accesses, ... */ | |
291 | MOVE_POSSIBLE /* Unlimited movement. */ | |
292 | }; | |
be35cf60 | 293 | |
a7e5372d ZD |
294 | |
295 | /* If it is possible to hoist the statement STMT unconditionally, | |
296 | returns MOVE_POSSIBLE. | |
297 | If it is possible to hoist the statement STMT, but we must avoid making | |
298 | it executed if it would not be executed in the original program (e.g. | |
299 | because it may trap), return MOVE_PRESERVE_EXECUTION. | |
300 | Otherwise return MOVE_IMPOSSIBLE. */ | |
301 | ||
40923b20 | 302 | enum move_pos |
355fe088 | 303 | movement_possibility (gimple *stmt) |
a7e5372d | 304 | { |
726a989a RB |
305 | tree lhs; |
306 | enum move_pos ret = MOVE_POSSIBLE; | |
a7e5372d ZD |
307 | |
308 | if (flag_unswitch_loops | |
726a989a | 309 | && gimple_code (stmt) == GIMPLE_COND) |
a7e5372d ZD |
310 | { |
311 | /* If we perform unswitching, force the operands of the invariant | |
312 | condition to be moved out of the loop. */ | |
a7e5372d ZD |
313 | return MOVE_POSSIBLE; |
314 | } | |
315 | ||
e3bdfed6 RG |
316 | if (gimple_code (stmt) == GIMPLE_PHI |
317 | && gimple_phi_num_args (stmt) <= 2 | |
ea057359 | 318 | && !virtual_operand_p (gimple_phi_result (stmt)) |
e3bdfed6 RG |
319 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_phi_result (stmt))) |
320 | return MOVE_POSSIBLE; | |
321 | ||
726a989a | 322 | if (gimple_get_lhs (stmt) == NULL_TREE) |
a7e5372d ZD |
323 | return MOVE_IMPOSSIBLE; |
324 | ||
5006671f | 325 | if (gimple_vdef (stmt)) |
72425608 ZD |
326 | return MOVE_IMPOSSIBLE; |
327 | ||
726a989a RB |
328 | if (stmt_ends_bb_p (stmt) |
329 | || gimple_has_volatile_ops (stmt) | |
330 | || gimple_has_side_effects (stmt) | |
36bbc05d | 331 | || stmt_could_throw_p (cfun, stmt)) |
a7e5372d ZD |
332 | return MOVE_IMPOSSIBLE; |
333 | ||
726a989a | 334 | if (is_gimple_call (stmt)) |
f10a6654 ZD |
335 | { |
336 | /* While pure or const call is guaranteed to have no side effects, we | |
337 | cannot move it arbitrarily. Consider code like | |
338 | ||
339 | char *s = something (); | |
340 | ||
341 | while (1) | |
342 | { | |
343 | if (s) | |
344 | t = strlen (s); | |
345 | else | |
346 | t = 0; | |
347 | } | |
348 | ||
349 | Here the strlen call cannot be moved out of the loop, even though | |
350 | s is invariant. In addition to possibly creating a call with | |
351 | invalid arguments, moving out a function call that is not executed | |
352 | may cause performance regressions in case the call is costly and | |
353 | not executed at all. */ | |
726a989a RB |
354 | ret = MOVE_PRESERVE_EXECUTION; |
355 | lhs = gimple_call_lhs (stmt); | |
f10a6654 | 356 | } |
726a989a RB |
357 | else if (is_gimple_assign (stmt)) |
358 | lhs = gimple_assign_lhs (stmt); | |
359 | else | |
360 | return MOVE_IMPOSSIBLE; | |
361 | ||
362 | if (TREE_CODE (lhs) == SSA_NAME | |
363 | && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) | |
364 | return MOVE_IMPOSSIBLE; | |
365 | ||
366 | if (TREE_CODE (lhs) != SSA_NAME | |
367 | || gimple_could_trap_p (stmt)) | |
368 | return MOVE_PRESERVE_EXECUTION; | |
369 | ||
19c0d7df AH |
370 | /* Non local loads in a transaction cannot be hoisted out. Well, |
371 | unless the load happens on every path out of the loop, but we | |
372 | don't take this into account yet. */ | |
373 | if (flag_tm | |
374 | && gimple_in_transaction (stmt) | |
375 | && gimple_assign_single_p (stmt)) | |
376 | { | |
377 | tree rhs = gimple_assign_rhs1 (stmt); | |
378 | if (DECL_P (rhs) && is_global_var (rhs)) | |
379 | { | |
380 | if (dump_file) | |
381 | { | |
382 | fprintf (dump_file, "Cannot hoist conditional load of "); | |
383 | print_generic_expr (dump_file, rhs, TDF_SLIM); | |
384 | fprintf (dump_file, " because it is in a transaction.\n"); | |
385 | } | |
386 | return MOVE_IMPOSSIBLE; | |
387 | } | |
388 | } | |
389 | ||
726a989a | 390 | return ret; |
a7e5372d ZD |
391 | } |
392 | ||
393 | /* Suppose that operand DEF is used inside the LOOP. Returns the outermost | |
2a7e31df | 394 | loop to that we could move the expression using DEF if it did not have |
a7e5372d ZD |
395 | other operands, i.e. the outermost loop enclosing LOOP in that the value |
396 | of DEF is invariant. */ | |
397 | ||
99b1c316 MS |
398 | static class loop * |
399 | outermost_invariant_loop (tree def, class loop *loop) | |
a7e5372d | 400 | { |
355fe088 | 401 | gimple *def_stmt; |
a7e5372d | 402 | basic_block def_bb; |
99b1c316 | 403 | class loop *max_loop; |
726a989a | 404 | struct lim_aux_data *lim_data; |
a7e5372d | 405 | |
726a989a | 406 | if (!def) |
a7e5372d ZD |
407 | return superloop_at_depth (loop, 1); |
408 | ||
726a989a RB |
409 | if (TREE_CODE (def) != SSA_NAME) |
410 | { | |
411 | gcc_assert (is_gimple_min_invariant (def)); | |
412 | return superloop_at_depth (loop, 1); | |
413 | } | |
414 | ||
a7e5372d | 415 | def_stmt = SSA_NAME_DEF_STMT (def); |
726a989a | 416 | def_bb = gimple_bb (def_stmt); |
a7e5372d ZD |
417 | if (!def_bb) |
418 | return superloop_at_depth (loop, 1); | |
419 | ||
420 | max_loop = find_common_loop (loop, def_bb->loop_father); | |
421 | ||
726a989a RB |
422 | lim_data = get_lim_data (def_stmt); |
423 | if (lim_data != NULL && lim_data->max_loop != NULL) | |
a7e5372d | 424 | max_loop = find_common_loop (max_loop, |
726a989a | 425 | loop_outer (lim_data->max_loop)); |
a7e5372d ZD |
426 | if (max_loop == loop) |
427 | return NULL; | |
9ba025a2 | 428 | max_loop = superloop_at_depth (loop, loop_depth (max_loop) + 1); |
a7e5372d ZD |
429 | |
430 | return max_loop; | |
431 | } | |
432 | ||
a7e5372d ZD |
433 | /* DATA is a structure containing information associated with a statement |
434 | inside LOOP. DEF is one of the operands of this statement. | |
b8698a0f | 435 | |
a7e5372d ZD |
436 | Find the outermost loop enclosing LOOP in that value of DEF is invariant |
437 | and record this in DATA->max_loop field. If DEF itself is defined inside | |
438 | this loop as well (i.e. we need to hoist it out of the loop if we want | |
439 | to hoist the statement represented by DATA), record the statement in that | |
440 | DEF is defined to the DATA->depends list. Additionally if ADD_COST is true, | |
441 | add the cost of the computation of DEF to the DATA->cost. | |
b8698a0f | 442 | |
a7e5372d ZD |
443 | If DEF is not invariant in LOOP, return false. Otherwise return TRUE. */ |
444 | ||
445 | static bool | |
99b1c316 | 446 | add_dependency (tree def, struct lim_aux_data *data, class loop *loop, |
a7e5372d ZD |
447 | bool add_cost) |
448 | { | |
355fe088 | 449 | gimple *def_stmt = SSA_NAME_DEF_STMT (def); |
726a989a | 450 | basic_block def_bb = gimple_bb (def_stmt); |
99b1c316 | 451 | class loop *max_loop; |
726a989a | 452 | struct lim_aux_data *def_data; |
a7e5372d ZD |
453 | |
454 | if (!def_bb) | |
455 | return true; | |
456 | ||
457 | max_loop = outermost_invariant_loop (def, loop); | |
458 | if (!max_loop) | |
459 | return false; | |
460 | ||
461 | if (flow_loop_nested_p (data->max_loop, max_loop)) | |
462 | data->max_loop = max_loop; | |
463 | ||
726a989a RB |
464 | def_data = get_lim_data (def_stmt); |
465 | if (!def_data) | |
a7e5372d ZD |
466 | return true; |
467 | ||
468 | if (add_cost | |
469 | /* Only add the cost if the statement defining DEF is inside LOOP, | |
470 | i.e. if it is likely that by moving the invariants dependent | |
471 | on it, we will be able to avoid creating a new register for | |
472 | it (since it will be only used in these dependent invariants). */ | |
473 | && def_bb->loop_father == loop) | |
726a989a | 474 | data->cost += def_data->cost; |
a7e5372d | 475 | |
76421b44 | 476 | data->depends.safe_push (def_stmt); |
a7e5372d ZD |
477 | |
478 | return true; | |
479 | } | |
480 | ||
546d314c RG |
481 | /* Returns an estimate for a cost of statement STMT. The values here |
482 | are just ad-hoc constants, similar to costs for inlining. */ | |
a7e5372d ZD |
483 | |
484 | static unsigned | |
355fe088 | 485 | stmt_cost (gimple *stmt) |
a7e5372d | 486 | { |
a7e5372d | 487 | /* Always try to create possibilities for unswitching. */ |
e3bdfed6 RG |
488 | if (gimple_code (stmt) == GIMPLE_COND |
489 | || gimple_code (stmt) == GIMPLE_PHI) | |
a7e5372d ZD |
490 | return LIM_EXPENSIVE; |
491 | ||
546d314c | 492 | /* We should be hoisting calls if possible. */ |
726a989a | 493 | if (is_gimple_call (stmt)) |
a7e5372d | 494 | { |
546d314c | 495 | tree fndecl; |
a7e5372d ZD |
496 | |
497 | /* Unless the call is a builtin_constant_p; this always folds to a | |
498 | constant, so moving it is useless. */ | |
726a989a | 499 | fndecl = gimple_call_fndecl (stmt); |
3d78e008 | 500 | if (fndecl && fndecl_built_in_p (fndecl, BUILT_IN_CONSTANT_P)) |
a7e5372d ZD |
501 | return 0; |
502 | ||
546d314c | 503 | return LIM_EXPENSIVE; |
726a989a RB |
504 | } |
505 | ||
546d314c RG |
506 | /* Hoisting memory references out should almost surely be a win. */ |
507 | if (gimple_references_memory_p (stmt)) | |
508 | return LIM_EXPENSIVE; | |
509 | ||
726a989a | 510 | if (gimple_code (stmt) != GIMPLE_ASSIGN) |
546d314c | 511 | return 1; |
a7e5372d | 512 | |
726a989a RB |
513 | switch (gimple_assign_rhs_code (stmt)) |
514 | { | |
a7e5372d | 515 | case MULT_EXPR: |
67af611e RG |
516 | case WIDEN_MULT_EXPR: |
517 | case WIDEN_MULT_PLUS_EXPR: | |
518 | case WIDEN_MULT_MINUS_EXPR: | |
519 | case DOT_PROD_EXPR: | |
a7e5372d ZD |
520 | case TRUNC_DIV_EXPR: |
521 | case CEIL_DIV_EXPR: | |
522 | case FLOOR_DIV_EXPR: | |
523 | case ROUND_DIV_EXPR: | |
524 | case EXACT_DIV_EXPR: | |
525 | case CEIL_MOD_EXPR: | |
526 | case FLOOR_MOD_EXPR: | |
527 | case ROUND_MOD_EXPR: | |
528 | case TRUNC_MOD_EXPR: | |
b4852851 | 529 | case RDIV_EXPR: |
a7e5372d | 530 | /* Division and multiplication are usually expensive. */ |
546d314c | 531 | return LIM_EXPENSIVE; |
a7e5372d | 532 | |
e0a60731 RG |
533 | case LSHIFT_EXPR: |
534 | case RSHIFT_EXPR: | |
67af611e RG |
535 | case WIDEN_LSHIFT_EXPR: |
536 | case LROTATE_EXPR: | |
537 | case RROTATE_EXPR: | |
546d314c RG |
538 | /* Shifts and rotates are usually expensive. */ |
539 | return LIM_EXPENSIVE; | |
540 | ||
541 | case CONSTRUCTOR: | |
542 | /* Make vector construction cost proportional to the number | |
543 | of elements. */ | |
544 | return CONSTRUCTOR_NELTS (gimple_assign_rhs1 (stmt)); | |
545 | ||
546 | case SSA_NAME: | |
547 | case PAREN_EXPR: | |
548 | /* Whether or not something is wrapped inside a PAREN_EXPR | |
549 | should not change move cost. Nor should an intermediate | |
550 | unpropagated SSA name copy. */ | |
551 | return 0; | |
e0a60731 | 552 | |
a7e5372d | 553 | default: |
546d314c | 554 | return 1; |
a7e5372d | 555 | } |
a7e5372d ZD |
556 | } |
557 | ||
72425608 ZD |
558 | /* Finds the outermost loop between OUTER and LOOP in that the memory reference |
559 | REF is independent. If REF is not independent in LOOP, NULL is returned | |
560 | instead. */ | |
561 | ||
99b1c316 MS |
562 | static class loop * |
563 | outermost_indep_loop (class loop *outer, class loop *loop, im_mem_ref *ref) | |
72425608 | 564 | { |
99b1c316 | 565 | class loop *aloop; |
72425608 | 566 | |
32500433 | 567 | if (ref->stored && bitmap_bit_p (ref->stored, loop->num)) |
72425608 ZD |
568 | return NULL; |
569 | ||
570 | for (aloop = outer; | |
571 | aloop != loop; | |
572 | aloop = superloop_at_depth (loop, loop_depth (aloop) + 1)) | |
32500433 | 573 | if ((!ref->stored || !bitmap_bit_p (ref->stored, aloop->num)) |
bcfaa720 | 574 | && ref_indep_loop_p (aloop, ref)) |
72425608 ZD |
575 | return aloop; |
576 | ||
bcfaa720 | 577 | if (ref_indep_loop_p (loop, ref)) |
72425608 ZD |
578 | return loop; |
579 | else | |
580 | return NULL; | |
581 | } | |
582 | ||
583 | /* If there is a simple load or store to a memory reference in STMT, returns | |
fa10beec | 584 | the location of the memory reference, and sets IS_STORE according to whether |
72425608 ZD |
585 | it is a store or load. Otherwise, returns NULL. */ |
586 | ||
587 | static tree * | |
355fe088 | 588 | simple_mem_ref_in_stmt (gimple *stmt, bool *is_store) |
72425608 | 589 | { |
1fc1ef37 | 590 | tree *lhs, *rhs; |
72425608 | 591 | |
1fc1ef37 EB |
592 | /* Recognize SSA_NAME = MEM and MEM = (SSA_NAME | invariant) patterns. */ |
593 | if (!gimple_assign_single_p (stmt)) | |
72425608 ZD |
594 | return NULL; |
595 | ||
726a989a | 596 | lhs = gimple_assign_lhs_ptr (stmt); |
1fc1ef37 | 597 | rhs = gimple_assign_rhs1_ptr (stmt); |
72425608 | 598 | |
1fc1ef37 | 599 | if (TREE_CODE (*lhs) == SSA_NAME && gimple_vuse (stmt)) |
72425608 | 600 | { |
72425608 | 601 | *is_store = false; |
1fc1ef37 | 602 | return rhs; |
72425608 | 603 | } |
1fc1ef37 EB |
604 | else if (gimple_vdef (stmt) |
605 | && (TREE_CODE (*rhs) == SSA_NAME || is_gimple_min_invariant (*rhs))) | |
72425608 ZD |
606 | { |
607 | *is_store = true; | |
608 | return lhs; | |
609 | } | |
610 | else | |
611 | return NULL; | |
612 | } | |
613 | ||
e3bdfed6 RG |
614 | /* From a controlling predicate in DOM determine the arguments from |
615 | the PHI node PHI that are chosen if the predicate evaluates to | |
616 | true and false and store them to *TRUE_ARG_P and *FALSE_ARG_P if | |
617 | they are non-NULL. Returns true if the arguments can be determined, | |
618 | else return false. */ | |
619 | ||
620 | static bool | |
538dd0b7 | 621 | extract_true_false_args_from_phi (basic_block dom, gphi *phi, |
e3bdfed6 RG |
622 | tree *true_arg_p, tree *false_arg_p) |
623 | { | |
e6503e0a RB |
624 | edge te, fe; |
625 | if (! extract_true_false_controlled_edges (dom, gimple_bb (phi), | |
626 | &te, &fe)) | |
e3bdfed6 RG |
627 | return false; |
628 | ||
629 | if (true_arg_p) | |
e6503e0a | 630 | *true_arg_p = PHI_ARG_DEF (phi, te->dest_idx); |
e3bdfed6 | 631 | if (false_arg_p) |
e6503e0a | 632 | *false_arg_p = PHI_ARG_DEF (phi, fe->dest_idx); |
e3bdfed6 RG |
633 | |
634 | return true; | |
635 | } | |
636 | ||
a7e5372d ZD |
637 | /* Determine the outermost loop to that it is possible to hoist a statement |
638 | STMT and store it to LIM_DATA (STMT)->max_loop. To do this we determine | |
639 | the outermost loop in that the value computed by STMT is invariant. | |
640 | If MUST_PRESERVE_EXEC is true, additionally choose such a loop that | |
641 | we preserve the fact whether STMT is executed. It also fills other related | |
642 | information to LIM_DATA (STMT). | |
b8698a0f | 643 | |
a7e5372d ZD |
644 | The function returns false if STMT cannot be hoisted outside of the loop it |
645 | is defined in, and true otherwise. */ | |
646 | ||
647 | static bool | |
355fe088 | 648 | determine_max_movement (gimple *stmt, bool must_preserve_exec) |
a7e5372d | 649 | { |
726a989a | 650 | basic_block bb = gimple_bb (stmt); |
99b1c316 MS |
651 | class loop *loop = bb->loop_father; |
652 | class loop *level; | |
726a989a | 653 | struct lim_aux_data *lim_data = get_lim_data (stmt); |
4c124b4c AM |
654 | tree val; |
655 | ssa_op_iter iter; | |
b8698a0f | 656 | |
a7e5372d ZD |
657 | if (must_preserve_exec) |
658 | level = ALWAYS_EXECUTED_IN (bb); | |
659 | else | |
660 | level = superloop_at_depth (loop, 1); | |
661 | lim_data->max_loop = level; | |
662 | ||
538dd0b7 | 663 | if (gphi *phi = dyn_cast <gphi *> (stmt)) |
e3bdfed6 RG |
664 | { |
665 | use_operand_p use_p; | |
666 | unsigned min_cost = UINT_MAX; | |
667 | unsigned total_cost = 0; | |
668 | struct lim_aux_data *def_data; | |
669 | ||
670 | /* We will end up promoting dependencies to be unconditionally | |
671 | evaluated. For this reason the PHI cost (and thus the | |
672 | cost we remove from the loop by doing the invariant motion) | |
673 | is that of the cheapest PHI argument dependency chain. */ | |
538dd0b7 | 674 | FOR_EACH_PHI_ARG (use_p, phi, iter, SSA_OP_USE) |
e3bdfed6 RG |
675 | { |
676 | val = USE_FROM_PTR (use_p); | |
d969f3c1 | 677 | |
e3bdfed6 | 678 | if (TREE_CODE (val) != SSA_NAME) |
d969f3c1 CB |
679 | { |
680 | /* Assign const 1 to constants. */ | |
681 | min_cost = MIN (min_cost, 1); | |
682 | total_cost += 1; | |
683 | continue; | |
684 | } | |
e3bdfed6 RG |
685 | if (!add_dependency (val, lim_data, loop, false)) |
686 | return false; | |
a4ab23b6 | 687 | |
355fe088 | 688 | gimple *def_stmt = SSA_NAME_DEF_STMT (val); |
a4ab23b6 RB |
689 | if (gimple_bb (def_stmt) |
690 | && gimple_bb (def_stmt)->loop_father == loop) | |
e3bdfed6 | 691 | { |
a4ab23b6 RB |
692 | def_data = get_lim_data (def_stmt); |
693 | if (def_data) | |
694 | { | |
695 | min_cost = MIN (min_cost, def_data->cost); | |
696 | total_cost += def_data->cost; | |
697 | } | |
e3bdfed6 RG |
698 | } |
699 | } | |
700 | ||
a4ab23b6 | 701 | min_cost = MIN (min_cost, total_cost); |
e3bdfed6 RG |
702 | lim_data->cost += min_cost; |
703 | ||
538dd0b7 | 704 | if (gimple_phi_num_args (phi) > 1) |
e3bdfed6 RG |
705 | { |
706 | basic_block dom = get_immediate_dominator (CDI_DOMINATORS, bb); | |
355fe088 | 707 | gimple *cond; |
e3bdfed6 RG |
708 | if (gsi_end_p (gsi_last_bb (dom))) |
709 | return false; | |
710 | cond = gsi_stmt (gsi_last_bb (dom)); | |
711 | if (gimple_code (cond) != GIMPLE_COND) | |
712 | return false; | |
713 | /* Verify that this is an extended form of a diamond and | |
714 | the PHI arguments are completely controlled by the | |
715 | predicate in DOM. */ | |
538dd0b7 | 716 | if (!extract_true_false_args_from_phi (dom, phi, NULL, NULL)) |
e3bdfed6 RG |
717 | return false; |
718 | ||
719 | /* Fold in dependencies and cost of the condition. */ | |
720 | FOR_EACH_SSA_TREE_OPERAND (val, cond, iter, SSA_OP_USE) | |
721 | { | |
722 | if (!add_dependency (val, lim_data, loop, false)) | |
723 | return false; | |
724 | def_data = get_lim_data (SSA_NAME_DEF_STMT (val)); | |
725 | if (def_data) | |
524c2492 | 726 | lim_data->cost += def_data->cost; |
e3bdfed6 RG |
727 | } |
728 | ||
729 | /* We want to avoid unconditionally executing very expensive | |
730 | operations. As costs for our dependencies cannot be | |
731 | negative just claim we are not invariand for this case. | |
732 | We also are not sure whether the control-flow inside the | |
733 | loop will vanish. */ | |
734 | if (total_cost - min_cost >= 2 * LIM_EXPENSIVE | |
735 | && !(min_cost != 0 | |
736 | && total_cost / min_cost <= 2)) | |
737 | return false; | |
738 | ||
739 | /* Assume that the control-flow in the loop will vanish. | |
740 | ??? We should verify this and not artificially increase | |
741 | the cost if that is not the case. */ | |
742 | lim_data->cost += stmt_cost (stmt); | |
743 | } | |
744 | ||
745 | return true; | |
746 | } | |
747 | else | |
748 | FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_USE) | |
749 | if (!add_dependency (val, lim_data, loop, true)) | |
750 | return false; | |
a7e5372d | 751 | |
5006671f | 752 | if (gimple_vuse (stmt)) |
72425608 | 753 | { |
5164293a RB |
754 | im_mem_ref *ref |
755 | = lim_data ? memory_accesses.refs_list[lim_data->ref] : NULL; | |
756 | if (ref | |
757 | && MEM_ANALYZABLE (ref)) | |
72425608 | 758 | { |
5164293a RB |
759 | lim_data->max_loop = outermost_indep_loop (lim_data->max_loop, |
760 | loop, ref); | |
72425608 ZD |
761 | if (!lim_data->max_loop) |
762 | return false; | |
763 | } | |
5164293a RB |
764 | else if (! add_dependency (gimple_vuse (stmt), lim_data, loop, false)) |
765 | return false; | |
72425608 | 766 | } |
a7e5372d ZD |
767 | |
768 | lim_data->cost += stmt_cost (stmt); | |
769 | ||
770 | return true; | |
771 | } | |
772 | ||
773 | /* Suppose that some statement in ORIG_LOOP is hoisted to the loop LEVEL, | |
774 | and that one of the operands of this statement is computed by STMT. | |
775 | Ensure that STMT (together with all the statements that define its | |
776 | operands) is hoisted at least out of the loop LEVEL. */ | |
777 | ||
778 | static void | |
99b1c316 | 779 | set_level (gimple *stmt, class loop *orig_loop, class loop *level) |
a7e5372d | 780 | { |
99b1c316 | 781 | class loop *stmt_loop = gimple_bb (stmt)->loop_father; |
726a989a | 782 | struct lim_aux_data *lim_data; |
355fe088 | 783 | gimple *dep_stmt; |
76421b44 | 784 | unsigned i; |
a7e5372d ZD |
785 | |
786 | stmt_loop = find_common_loop (orig_loop, stmt_loop); | |
726a989a RB |
787 | lim_data = get_lim_data (stmt); |
788 | if (lim_data != NULL && lim_data->tgt_loop != NULL) | |
a7e5372d | 789 | stmt_loop = find_common_loop (stmt_loop, |
726a989a | 790 | loop_outer (lim_data->tgt_loop)); |
a7e5372d ZD |
791 | if (flow_loop_nested_p (stmt_loop, level)) |
792 | return; | |
793 | ||
726a989a RB |
794 | gcc_assert (level == lim_data->max_loop |
795 | || flow_loop_nested_p (lim_data->max_loop, level)); | |
a7e5372d | 796 | |
726a989a | 797 | lim_data->tgt_loop = level; |
76421b44 RB |
798 | FOR_EACH_VEC_ELT (lim_data->depends, i, dep_stmt) |
799 | set_level (dep_stmt, orig_loop, level); | |
a7e5372d ZD |
800 | } |
801 | ||
802 | /* Determines an outermost loop from that we want to hoist the statement STMT. | |
803 | For now we chose the outermost possible loop. TODO -- use profiling | |
804 | information to set it more sanely. */ | |
805 | ||
806 | static void | |
355fe088 | 807 | set_profitable_level (gimple *stmt) |
a7e5372d | 808 | { |
726a989a | 809 | set_level (stmt, gimple_bb (stmt)->loop_father, get_lim_data (stmt)->max_loop); |
a7e5372d ZD |
810 | } |
811 | ||
726a989a | 812 | /* Returns true if STMT is a call that has side effects. */ |
a7e5372d ZD |
813 | |
814 | static bool | |
355fe088 | 815 | nonpure_call_p (gimple *stmt) |
a7e5372d | 816 | { |
726a989a | 817 | if (gimple_code (stmt) != GIMPLE_CALL) |
a7e5372d ZD |
818 | return false; |
819 | ||
726a989a | 820 | return gimple_has_side_effects (stmt); |
a7e5372d ZD |
821 | } |
822 | ||
e0a60731 RG |
823 | /* Rewrite a/b to a*(1/b). Return the invariant stmt to process. */ |
824 | ||
355fe088 | 825 | static gimple * |
726a989a | 826 | rewrite_reciprocal (gimple_stmt_iterator *bsi) |
e0a60731 | 827 | { |
538dd0b7 | 828 | gassign *stmt, *stmt1, *stmt2; |
83d5977e | 829 | tree name, lhs, type; |
f50d67f6 | 830 | tree real_one; |
0ca5af51 | 831 | gimple_stmt_iterator gsi; |
e0a60731 | 832 | |
538dd0b7 | 833 | stmt = as_a <gassign *> (gsi_stmt (*bsi)); |
726a989a RB |
834 | lhs = gimple_assign_lhs (stmt); |
835 | type = TREE_TYPE (lhs); | |
e0a60731 | 836 | |
8e8e423f | 837 | real_one = build_one_cst (type); |
e0a60731 | 838 | |
83d5977e | 839 | name = make_temp_ssa_name (type, NULL, "reciptmp"); |
0d0e4a03 JJ |
840 | stmt1 = gimple_build_assign (name, RDIV_EXPR, real_one, |
841 | gimple_assign_rhs2 (stmt)); | |
842 | stmt2 = gimple_build_assign (lhs, MULT_EXPR, name, | |
843 | gimple_assign_rhs1 (stmt)); | |
e0a60731 RG |
844 | |
845 | /* Replace division stmt with reciprocal and multiply stmts. | |
846 | The multiply stmt is not invariant, so update iterator | |
847 | and avoid rescanning. */ | |
0ca5af51 AO |
848 | gsi = *bsi; |
849 | gsi_insert_before (bsi, stmt1, GSI_NEW_STMT); | |
850 | gsi_replace (&gsi, stmt2, true); | |
e0a60731 RG |
851 | |
852 | /* Continue processing with invariant reciprocal statement. */ | |
853 | return stmt1; | |
854 | } | |
855 | ||
856 | /* Check if the pattern at *BSI is a bittest of the form | |
857 | (A >> B) & 1 != 0 and in this case rewrite it to A & (1 << B) != 0. */ | |
858 | ||
355fe088 | 859 | static gimple * |
726a989a | 860 | rewrite_bittest (gimple_stmt_iterator *bsi) |
e0a60731 | 861 | { |
538dd0b7 | 862 | gassign *stmt; |
355fe088 | 863 | gimple *stmt1; |
538dd0b7 | 864 | gassign *stmt2; |
355fe088 | 865 | gimple *use_stmt; |
538dd0b7 | 866 | gcond *cond_stmt; |
83d5977e | 867 | tree lhs, name, t, a, b; |
e0a60731 RG |
868 | use_operand_p use; |
869 | ||
538dd0b7 | 870 | stmt = as_a <gassign *> (gsi_stmt (*bsi)); |
726a989a | 871 | lhs = gimple_assign_lhs (stmt); |
e0a60731 RG |
872 | |
873 | /* Verify that the single use of lhs is a comparison against zero. */ | |
874 | if (TREE_CODE (lhs) != SSA_NAME | |
538dd0b7 | 875 | || !single_imm_use (lhs, &use, &use_stmt)) |
e0a60731 | 876 | return stmt; |
538dd0b7 DM |
877 | cond_stmt = dyn_cast <gcond *> (use_stmt); |
878 | if (!cond_stmt) | |
879 | return stmt; | |
880 | if (gimple_cond_lhs (cond_stmt) != lhs | |
881 | || (gimple_cond_code (cond_stmt) != NE_EXPR | |
882 | && gimple_cond_code (cond_stmt) != EQ_EXPR) | |
883 | || !integer_zerop (gimple_cond_rhs (cond_stmt))) | |
e0a60731 RG |
884 | return stmt; |
885 | ||
886 | /* Get at the operands of the shift. The rhs is TMP1 & 1. */ | |
726a989a RB |
887 | stmt1 = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (stmt)); |
888 | if (gimple_code (stmt1) != GIMPLE_ASSIGN) | |
e0a60731 RG |
889 | return stmt; |
890 | ||
0d52bcc1 | 891 | /* There is a conversion in between possibly inserted by fold. */ |
1a87cf0c | 892 | if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt1))) |
e0a60731 | 893 | { |
726a989a | 894 | t = gimple_assign_rhs1 (stmt1); |
e0a60731 RG |
895 | if (TREE_CODE (t) != SSA_NAME |
896 | || !has_single_use (t)) | |
897 | return stmt; | |
898 | stmt1 = SSA_NAME_DEF_STMT (t); | |
726a989a | 899 | if (gimple_code (stmt1) != GIMPLE_ASSIGN) |
e0a60731 | 900 | return stmt; |
e0a60731 RG |
901 | } |
902 | ||
903 | /* Verify that B is loop invariant but A is not. Verify that with | |
904 | all the stmt walking we are still in the same loop. */ | |
726a989a RB |
905 | if (gimple_assign_rhs_code (stmt1) != RSHIFT_EXPR |
906 | || loop_containing_stmt (stmt1) != loop_containing_stmt (stmt)) | |
907 | return stmt; | |
e0a60731 | 908 | |
726a989a RB |
909 | a = gimple_assign_rhs1 (stmt1); |
910 | b = gimple_assign_rhs2 (stmt1); | |
911 | ||
912 | if (outermost_invariant_loop (b, loop_containing_stmt (stmt1)) != NULL | |
913 | && outermost_invariant_loop (a, loop_containing_stmt (stmt1)) == NULL) | |
914 | { | |
0ca5af51 AO |
915 | gimple_stmt_iterator rsi; |
916 | ||
e0a60731 | 917 | /* 1 << B */ |
e0a60731 RG |
918 | t = fold_build2 (LSHIFT_EXPR, TREE_TYPE (a), |
919 | build_int_cst (TREE_TYPE (a), 1), b); | |
83d5977e RG |
920 | name = make_temp_ssa_name (TREE_TYPE (a), NULL, "shifttmp"); |
921 | stmt1 = gimple_build_assign (name, t); | |
e0a60731 RG |
922 | |
923 | /* A & (1 << B) */ | |
924 | t = fold_build2 (BIT_AND_EXPR, TREE_TYPE (a), a, name); | |
83d5977e RG |
925 | name = make_temp_ssa_name (TREE_TYPE (a), NULL, "shifttmp"); |
926 | stmt2 = gimple_build_assign (name, t); | |
a6e2d112 UB |
927 | |
928 | /* Replace the SSA_NAME we compare against zero. Adjust | |
929 | the type of zero accordingly. */ | |
5c7ec4f0 | 930 | SET_USE (use, name); |
538dd0b7 DM |
931 | gimple_cond_set_rhs (cond_stmt, |
932 | build_int_cst_type (TREE_TYPE (name), | |
933 | 0)); | |
e0a60731 | 934 | |
0ca5af51 AO |
935 | /* Don't use gsi_replace here, none of the new assignments sets |
936 | the variable originally set in stmt. Move bsi to stmt1, and | |
937 | then remove the original stmt, so that we get a chance to | |
938 | retain debug info for it. */ | |
939 | rsi = *bsi; | |
940 | gsi_insert_before (bsi, stmt1, GSI_NEW_STMT); | |
941 | gsi_insert_before (&rsi, stmt2, GSI_SAME_STMT); | |
716e92f4 | 942 | gimple *to_release = gsi_stmt (rsi); |
0ca5af51 | 943 | gsi_remove (&rsi, true); |
716e92f4 | 944 | release_defs (to_release); |
e0a60731 RG |
945 | |
946 | return stmt1; | |
947 | } | |
948 | ||
949 | return stmt; | |
950 | } | |
951 | ||
4d9192b5 TS |
952 | /* For each statement determines the outermost loop in that it is invariant, |
953 | - statements on whose motion it depends and the cost of the computation. | |
954 | - This information is stored to the LIM_DATA structure associated with | |
955 | - each statement. */ | |
956 | class invariantness_dom_walker : public dom_walker | |
957 | { | |
958 | public: | |
959 | invariantness_dom_walker (cdi_direction direction) | |
960 | : dom_walker (direction) {} | |
961 | ||
3daacdcd | 962 | virtual edge before_dom_children (basic_block); |
4d9192b5 | 963 | }; |
e0a60731 | 964 | |
a7e5372d ZD |
965 | /* Determine the outermost loops in that statements in basic block BB are |
966 | invariant, and record them to the LIM_DATA associated with the statements. | |
4d9192b5 | 967 | Callback for dom_walker. */ |
a7e5372d | 968 | |
3daacdcd | 969 | edge |
4d9192b5 | 970 | invariantness_dom_walker::before_dom_children (basic_block bb) |
a7e5372d ZD |
971 | { |
972 | enum move_pos pos; | |
726a989a | 973 | gimple_stmt_iterator bsi; |
355fe088 | 974 | gimple *stmt; |
a7e5372d | 975 | bool maybe_never = ALWAYS_EXECUTED_IN (bb) == NULL; |
99b1c316 | 976 | class loop *outermost = ALWAYS_EXECUTED_IN (bb); |
726a989a | 977 | struct lim_aux_data *lim_data; |
a7e5372d | 978 | |
9ba025a2 | 979 | if (!loop_outer (bb->loop_father)) |
3daacdcd | 980 | return NULL; |
a7e5372d ZD |
981 | |
982 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
983 | fprintf (dump_file, "Basic block %d (loop %d -- depth %d):\n\n", | |
9ba025a2 | 984 | bb->index, bb->loop_father->num, loop_depth (bb->loop_father)); |
a7e5372d | 985 | |
e3bdfed6 RG |
986 | /* Look at PHI nodes, but only if there is at most two. |
987 | ??? We could relax this further by post-processing the inserted | |
988 | code and transforming adjacent cond-exprs with the same predicate | |
989 | to control flow again. */ | |
990 | bsi = gsi_start_phis (bb); | |
991 | if (!gsi_end_p (bsi) | |
992 | && ((gsi_next (&bsi), gsi_end_p (bsi)) | |
993 | || (gsi_next (&bsi), gsi_end_p (bsi)))) | |
994 | for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
995 | { | |
996 | stmt = gsi_stmt (bsi); | |
997 | ||
998 | pos = movement_possibility (stmt); | |
999 | if (pos == MOVE_IMPOSSIBLE) | |
1000 | continue; | |
1001 | ||
5164293a RB |
1002 | lim_data = get_lim_data (stmt); |
1003 | if (! lim_data) | |
1004 | lim_data = init_lim_data (stmt); | |
e3bdfed6 RG |
1005 | lim_data->always_executed_in = outermost; |
1006 | ||
1007 | if (!determine_max_movement (stmt, false)) | |
1008 | { | |
1009 | lim_data->max_loop = NULL; | |
1010 | continue; | |
1011 | } | |
1012 | ||
1013 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1014 | { | |
ef6cb4c7 | 1015 | print_gimple_stmt (dump_file, stmt, 2); |
e3bdfed6 RG |
1016 | fprintf (dump_file, " invariant up to level %d, cost %d.\n\n", |
1017 | loop_depth (lim_data->max_loop), | |
1018 | lim_data->cost); | |
1019 | } | |
1020 | ||
1021 | if (lim_data->cost >= LIM_EXPENSIVE) | |
1022 | set_profitable_level (stmt); | |
1023 | } | |
1024 | ||
726a989a | 1025 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
a7e5372d | 1026 | { |
726a989a | 1027 | stmt = gsi_stmt (bsi); |
a7e5372d ZD |
1028 | |
1029 | pos = movement_possibility (stmt); | |
1030 | if (pos == MOVE_IMPOSSIBLE) | |
1031 | { | |
1032 | if (nonpure_call_p (stmt)) | |
1033 | { | |
1034 | maybe_never = true; | |
1035 | outermost = NULL; | |
1036 | } | |
8ded35f9 RG |
1037 | /* Make sure to note always_executed_in for stores to make |
1038 | store-motion work. */ | |
1039 | else if (stmt_makes_single_store (stmt)) | |
1040 | { | |
5164293a RB |
1041 | struct lim_aux_data *lim_data = get_lim_data (stmt); |
1042 | if (! lim_data) | |
1043 | lim_data = init_lim_data (stmt); | |
726a989a | 1044 | lim_data->always_executed_in = outermost; |
8ded35f9 | 1045 | } |
a7e5372d ZD |
1046 | continue; |
1047 | } | |
1048 | ||
726a989a RB |
1049 | if (is_gimple_assign (stmt) |
1050 | && (get_gimple_rhs_class (gimple_assign_rhs_code (stmt)) | |
1051 | == GIMPLE_BINARY_RHS)) | |
a9b77cd1 | 1052 | { |
726a989a RB |
1053 | tree op0 = gimple_assign_rhs1 (stmt); |
1054 | tree op1 = gimple_assign_rhs2 (stmt); | |
99b1c316 | 1055 | class loop *ol1 = outermost_invariant_loop (op1, |
726a989a | 1056 | loop_containing_stmt (stmt)); |
a9b77cd1 ZD |
1057 | |
1058 | /* If divisor is invariant, convert a/b to a*(1/b), allowing reciprocal | |
1059 | to be hoisted out of loop, saving expensive divide. */ | |
1060 | if (pos == MOVE_POSSIBLE | |
726a989a | 1061 | && gimple_assign_rhs_code (stmt) == RDIV_EXPR |
a9b77cd1 ZD |
1062 | && flag_unsafe_math_optimizations |
1063 | && !flag_trapping_math | |
726a989a RB |
1064 | && ol1 != NULL |
1065 | && outermost_invariant_loop (op0, ol1) == NULL) | |
a9b77cd1 ZD |
1066 | stmt = rewrite_reciprocal (&bsi); |
1067 | ||
1068 | /* If the shift count is invariant, convert (A >> B) & 1 to | |
1069 | A & (1 << B) allowing the bit mask to be hoisted out of the loop | |
1070 | saving an expensive shift. */ | |
1071 | if (pos == MOVE_POSSIBLE | |
726a989a RB |
1072 | && gimple_assign_rhs_code (stmt) == BIT_AND_EXPR |
1073 | && integer_onep (op1) | |
1074 | && TREE_CODE (op0) == SSA_NAME | |
1075 | && has_single_use (op0)) | |
a9b77cd1 ZD |
1076 | stmt = rewrite_bittest (&bsi); |
1077 | } | |
37cca405 | 1078 | |
5164293a RB |
1079 | lim_data = get_lim_data (stmt); |
1080 | if (! lim_data) | |
1081 | lim_data = init_lim_data (stmt); | |
726a989a | 1082 | lim_data->always_executed_in = outermost; |
a7e5372d ZD |
1083 | |
1084 | if (maybe_never && pos == MOVE_PRESERVE_EXECUTION) | |
1085 | continue; | |
1086 | ||
1087 | if (!determine_max_movement (stmt, pos == MOVE_PRESERVE_EXECUTION)) | |
1088 | { | |
726a989a | 1089 | lim_data->max_loop = NULL; |
a7e5372d ZD |
1090 | continue; |
1091 | } | |
1092 | ||
1093 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1094 | { | |
ef6cb4c7 | 1095 | print_gimple_stmt (dump_file, stmt, 2); |
a7e5372d | 1096 | fprintf (dump_file, " invariant up to level %d, cost %d.\n\n", |
726a989a RB |
1097 | loop_depth (lim_data->max_loop), |
1098 | lim_data->cost); | |
a7e5372d ZD |
1099 | } |
1100 | ||
726a989a | 1101 | if (lim_data->cost >= LIM_EXPENSIVE) |
a7e5372d ZD |
1102 | set_profitable_level (stmt); |
1103 | } | |
3daacdcd | 1104 | return NULL; |
a7e5372d ZD |
1105 | } |
1106 | ||
a7e5372d | 1107 | /* Hoist the statements in basic block BB out of the loops prescribed by |
2a7e31df | 1108 | data stored in LIM_DATA structures associated with each statement. Callback |
a7e5372d ZD |
1109 | for walk_dominator_tree. */ |
1110 | ||
22a08dd1 RB |
1111 | unsigned int |
1112 | move_computations_worker (basic_block bb) | |
a7e5372d | 1113 | { |
99b1c316 | 1114 | class loop *level; |
a7e5372d | 1115 | unsigned cost = 0; |
726a989a | 1116 | struct lim_aux_data *lim_data; |
22a08dd1 | 1117 | unsigned int todo = 0; |
a7e5372d | 1118 | |
9ba025a2 | 1119 | if (!loop_outer (bb->loop_father)) |
22a08dd1 | 1120 | return todo; |
a7e5372d | 1121 | |
538dd0b7 | 1122 | for (gphi_iterator bsi = gsi_start_phis (bb); !gsi_end_p (bsi); ) |
e3bdfed6 | 1123 | { |
538dd0b7 DM |
1124 | gassign *new_stmt; |
1125 | gphi *stmt = bsi.phi (); | |
e3bdfed6 RG |
1126 | |
1127 | lim_data = get_lim_data (stmt); | |
1128 | if (lim_data == NULL) | |
1129 | { | |
1130 | gsi_next (&bsi); | |
1131 | continue; | |
1132 | } | |
1133 | ||
1134 | cost = lim_data->cost; | |
1135 | level = lim_data->tgt_loop; | |
1136 | clear_lim_data (stmt); | |
1137 | ||
1138 | if (!level) | |
1139 | { | |
1140 | gsi_next (&bsi); | |
1141 | continue; | |
1142 | } | |
1143 | ||
1144 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1145 | { | |
1146 | fprintf (dump_file, "Moving PHI node\n"); | |
ef6cb4c7 | 1147 | print_gimple_stmt (dump_file, stmt, 0); |
e3bdfed6 RG |
1148 | fprintf (dump_file, "(cost %u) out of loop %d.\n\n", |
1149 | cost, level->num); | |
1150 | } | |
1151 | ||
1152 | if (gimple_phi_num_args (stmt) == 1) | |
1153 | { | |
1154 | tree arg = PHI_ARG_DEF (stmt, 0); | |
0d0e4a03 JJ |
1155 | new_stmt = gimple_build_assign (gimple_phi_result (stmt), |
1156 | TREE_CODE (arg), arg); | |
e3bdfed6 RG |
1157 | } |
1158 | else | |
1159 | { | |
1160 | basic_block dom = get_immediate_dominator (CDI_DOMINATORS, bb); | |
355fe088 | 1161 | gimple *cond = gsi_stmt (gsi_last_bb (dom)); |
e3bdfed6 RG |
1162 | tree arg0 = NULL_TREE, arg1 = NULL_TREE, t; |
1163 | /* Get the PHI arguments corresponding to the true and false | |
1164 | edges of COND. */ | |
1165 | extract_true_false_args_from_phi (dom, stmt, &arg0, &arg1); | |
1166 | gcc_assert (arg0 && arg1); | |
1167 | t = build2 (gimple_cond_code (cond), boolean_type_node, | |
1168 | gimple_cond_lhs (cond), gimple_cond_rhs (cond)); | |
0d0e4a03 JJ |
1169 | new_stmt = gimple_build_assign (gimple_phi_result (stmt), |
1170 | COND_EXPR, t, arg0, arg1); | |
22a08dd1 | 1171 | todo |= TODO_cleanup_cfg; |
e3bdfed6 | 1172 | } |
07faade6 RB |
1173 | if (INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (new_stmt))) |
1174 | && (!ALWAYS_EXECUTED_IN (bb) | |
1175 | || (ALWAYS_EXECUTED_IN (bb) != level | |
1176 | && !flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
a6377d52 JJ |
1177 | { |
1178 | tree lhs = gimple_assign_lhs (new_stmt); | |
1179 | SSA_NAME_RANGE_INFO (lhs) = NULL; | |
a6377d52 | 1180 | } |
e3bdfed6 RG |
1181 | gsi_insert_on_edge (loop_preheader_edge (level), new_stmt); |
1182 | remove_phi_node (&bsi, false); | |
1183 | } | |
1184 | ||
538dd0b7 | 1185 | for (gimple_stmt_iterator bsi = gsi_start_bb (bb); !gsi_end_p (bsi); ) |
a7e5372d | 1186 | { |
13714310 RG |
1187 | edge e; |
1188 | ||
355fe088 | 1189 | gimple *stmt = gsi_stmt (bsi); |
a7e5372d | 1190 | |
726a989a RB |
1191 | lim_data = get_lim_data (stmt); |
1192 | if (lim_data == NULL) | |
a7e5372d | 1193 | { |
726a989a | 1194 | gsi_next (&bsi); |
a7e5372d ZD |
1195 | continue; |
1196 | } | |
1197 | ||
726a989a RB |
1198 | cost = lim_data->cost; |
1199 | level = lim_data->tgt_loop; | |
1200 | clear_lim_data (stmt); | |
a7e5372d ZD |
1201 | |
1202 | if (!level) | |
1203 | { | |
726a989a | 1204 | gsi_next (&bsi); |
a7e5372d ZD |
1205 | continue; |
1206 | } | |
1207 | ||
1208 | /* We do not really want to move conditionals out of the loop; we just | |
1209 | placed it here to force its operands to be moved if necessary. */ | |
726a989a | 1210 | if (gimple_code (stmt) == GIMPLE_COND) |
a7e5372d ZD |
1211 | continue; |
1212 | ||
1213 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1214 | { | |
1215 | fprintf (dump_file, "Moving statement\n"); | |
ef6cb4c7 | 1216 | print_gimple_stmt (dump_file, stmt, 0); |
a7e5372d ZD |
1217 | fprintf (dump_file, "(cost %u) out of loop %d.\n\n", |
1218 | cost, level->num); | |
1219 | } | |
72425608 | 1220 | |
13714310 RG |
1221 | e = loop_preheader_edge (level); |
1222 | gcc_assert (!gimple_vdef (stmt)); | |
1223 | if (gimple_vuse (stmt)) | |
1224 | { | |
1225 | /* The new VUSE is the one from the virtual PHI in the loop | |
1226 | header or the one already present. */ | |
538dd0b7 | 1227 | gphi_iterator gsi2; |
13714310 RG |
1228 | for (gsi2 = gsi_start_phis (e->dest); |
1229 | !gsi_end_p (gsi2); gsi_next (&gsi2)) | |
1230 | { | |
538dd0b7 | 1231 | gphi *phi = gsi2.phi (); |
ea057359 | 1232 | if (virtual_operand_p (gimple_phi_result (phi))) |
13714310 RG |
1233 | { |
1234 | gimple_set_vuse (stmt, PHI_ARG_DEF_FROM_EDGE (phi, e)); | |
1235 | break; | |
1236 | } | |
1237 | } | |
1238 | } | |
726a989a | 1239 | gsi_remove (&bsi, false); |
07faade6 RB |
1240 | if (gimple_has_lhs (stmt) |
1241 | && TREE_CODE (gimple_get_lhs (stmt)) == SSA_NAME | |
1242 | && INTEGRAL_TYPE_P (TREE_TYPE (gimple_get_lhs (stmt))) | |
1243 | && (!ALWAYS_EXECUTED_IN (bb) | |
1244 | || !(ALWAYS_EXECUTED_IN (bb) == level | |
1245 | || flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
a6377d52 JJ |
1246 | { |
1247 | tree lhs = gimple_get_lhs (stmt); | |
1248 | SSA_NAME_RANGE_INFO (lhs) = NULL; | |
a6377d52 | 1249 | } |
f4bed77b RB |
1250 | /* In case this is a stmt that is not unconditionally executed |
1251 | when the target loop header is executed and the stmt may | |
1252 | invoke undefined integer or pointer overflow rewrite it to | |
1253 | unsigned arithmetic. */ | |
1254 | if (is_gimple_assign (stmt) | |
1255 | && INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (stmt))) | |
1256 | && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (gimple_assign_lhs (stmt))) | |
1257 | && arith_code_with_undefined_signed_overflow | |
1258 | (gimple_assign_rhs_code (stmt)) | |
1259 | && (!ALWAYS_EXECUTED_IN (bb) | |
1260 | || !(ALWAYS_EXECUTED_IN (bb) == level | |
1261 | || flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
1262 | gsi_insert_seq_on_edge (e, rewrite_to_defined_overflow (stmt)); | |
1263 | else | |
1264 | gsi_insert_on_edge (e, stmt); | |
a7e5372d | 1265 | } |
22a08dd1 RB |
1266 | |
1267 | return todo; | |
a7e5372d ZD |
1268 | } |
1269 | ||
1270 | /* Hoist the statements out of the loops prescribed by data stored in | |
2a7e31df | 1271 | LIM_DATA structures associated with each statement.*/ |
a7e5372d | 1272 | |
e3bdfed6 | 1273 | static unsigned int |
a7e5372d ZD |
1274 | move_computations (void) |
1275 | { | |
22a08dd1 RB |
1276 | int *rpo = XNEWVEC (int, last_basic_block_for_fn (cfun)); |
1277 | int n = pre_and_rev_post_order_compute_fn (cfun, NULL, rpo, false); | |
1278 | unsigned todo = 0; | |
1279 | ||
1280 | for (int i = 0; i < n; ++i) | |
1281 | todo |= move_computations_worker (BASIC_BLOCK_FOR_FN (cfun, rpo[i])); | |
1282 | ||
1283 | free (rpo); | |
a7e5372d | 1284 | |
726a989a | 1285 | gsi_commit_edge_inserts (); |
5006671f | 1286 | if (need_ssa_update_p (cfun)) |
84d65814 | 1287 | rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); |
e3bdfed6 | 1288 | |
22a08dd1 | 1289 | return todo; |
a7e5372d ZD |
1290 | } |
1291 | ||
1292 | /* Checks whether the statement defining variable *INDEX can be hoisted | |
1293 | out of the loop passed in DATA. Callback for for_each_index. */ | |
1294 | ||
1295 | static bool | |
1296 | may_move_till (tree ref, tree *index, void *data) | |
1297 | { | |
99b1c316 | 1298 | class loop *loop = (class loop *) data, *max_loop; |
a7e5372d ZD |
1299 | |
1300 | /* If REF is an array reference, check also that the step and the lower | |
1301 | bound is invariant in LOOP. */ | |
1302 | if (TREE_CODE (ref) == ARRAY_REF) | |
1303 | { | |
726a989a RB |
1304 | tree step = TREE_OPERAND (ref, 3); |
1305 | tree lbound = TREE_OPERAND (ref, 2); | |
a7e5372d | 1306 | |
726a989a | 1307 | max_loop = outermost_invariant_loop (step, loop); |
a7e5372d ZD |
1308 | if (!max_loop) |
1309 | return false; | |
1310 | ||
726a989a | 1311 | max_loop = outermost_invariant_loop (lbound, loop); |
a7e5372d ZD |
1312 | if (!max_loop) |
1313 | return false; | |
1314 | } | |
1315 | ||
1316 | max_loop = outermost_invariant_loop (*index, loop); | |
1317 | if (!max_loop) | |
1318 | return false; | |
1319 | ||
1320 | return true; | |
1321 | } | |
1322 | ||
726a989a | 1323 | /* If OP is SSA NAME, force the statement that defines it to be |
b4042a03 | 1324 | moved out of the LOOP. ORIG_LOOP is the loop in that EXPR is used. */ |
a7e5372d ZD |
1325 | |
1326 | static void | |
99b1c316 | 1327 | force_move_till_op (tree op, class loop *orig_loop, class loop *loop) |
a7e5372d | 1328 | { |
355fe088 | 1329 | gimple *stmt; |
a7e5372d | 1330 | |
726a989a RB |
1331 | if (!op |
1332 | || is_gimple_min_invariant (op)) | |
1333 | return; | |
a7e5372d | 1334 | |
726a989a | 1335 | gcc_assert (TREE_CODE (op) == SSA_NAME); |
b8698a0f | 1336 | |
726a989a RB |
1337 | stmt = SSA_NAME_DEF_STMT (op); |
1338 | if (gimple_nop_p (stmt)) | |
a7e5372d ZD |
1339 | return; |
1340 | ||
726a989a | 1341 | set_level (stmt, orig_loop, loop); |
a7e5372d ZD |
1342 | } |
1343 | ||
1344 | /* Forces statement defining invariants in REF (and *INDEX) to be moved out of | |
b4042a03 ZD |
1345 | the LOOP. The reference REF is used in the loop ORIG_LOOP. Callback for |
1346 | for_each_index. */ | |
1347 | ||
1348 | struct fmt_data | |
1349 | { | |
99b1c316 MS |
1350 | class loop *loop; |
1351 | class loop *orig_loop; | |
b4042a03 | 1352 | }; |
a7e5372d ZD |
1353 | |
1354 | static bool | |
1355 | force_move_till (tree ref, tree *index, void *data) | |
1356 | { | |
c22940cd | 1357 | struct fmt_data *fmt_data = (struct fmt_data *) data; |
a7e5372d ZD |
1358 | |
1359 | if (TREE_CODE (ref) == ARRAY_REF) | |
1360 | { | |
726a989a RB |
1361 | tree step = TREE_OPERAND (ref, 3); |
1362 | tree lbound = TREE_OPERAND (ref, 2); | |
a7e5372d | 1363 | |
726a989a RB |
1364 | force_move_till_op (step, fmt_data->orig_loop, fmt_data->loop); |
1365 | force_move_till_op (lbound, fmt_data->orig_loop, fmt_data->loop); | |
a7e5372d ZD |
1366 | } |
1367 | ||
726a989a | 1368 | force_move_till_op (*index, fmt_data->orig_loop, fmt_data->loop); |
a7e5372d ZD |
1369 | |
1370 | return true; | |
1371 | } | |
1372 | ||
72425608 ZD |
1373 | /* A function to free the mem_ref object OBJ. */ |
1374 | ||
1375 | static void | |
99b1c316 | 1376 | memref_free (class im_mem_ref *mem) |
72425608 | 1377 | { |
9771b263 | 1378 | mem->accesses_in_loop.release (); |
72425608 ZD |
1379 | } |
1380 | ||
1381 | /* Allocates and returns a memory reference description for MEM whose hash | |
1382 | value is HASH and id is ID. */ | |
1383 | ||
61baec41 | 1384 | static im_mem_ref * |
1c852d1d | 1385 | mem_ref_alloc (ao_ref *mem, unsigned hash, unsigned id) |
72425608 | 1386 | { |
99b1c316 | 1387 | im_mem_ref *ref = XOBNEW (&mem_ref_obstack, class im_mem_ref); |
1c852d1d RB |
1388 | if (mem) |
1389 | ref->mem = *mem; | |
1390 | else | |
1391 | ao_ref_init (&ref->mem, error_mark_node); | |
72425608 | 1392 | ref->id = id; |
1c852d1d | 1393 | ref->ref_canonical = false; |
a8aa828b | 1394 | ref->ref_decomposed = false; |
72425608 | 1395 | ref->hash = hash; |
32500433 | 1396 | ref->stored = NULL; |
374001cb RB |
1397 | bitmap_initialize (&ref->indep_loop, &lim_bitmap_obstack); |
1398 | bitmap_initialize (&ref->dep_loop, &lim_bitmap_obstack); | |
32500433 | 1399 | ref->accesses_in_loop.create (1); |
72425608 ZD |
1400 | |
1401 | return ref; | |
1402 | } | |
1403 | ||
72425608 ZD |
1404 | /* Records memory reference location *LOC in LOOP to the memory reference |
1405 | description REF. The reference occurs in statement STMT. */ | |
a7e5372d ZD |
1406 | |
1407 | static void | |
355fe088 | 1408 | record_mem_ref_loc (im_mem_ref *ref, gimple *stmt, tree *loc) |
a7e5372d | 1409 | { |
15d19bf8 | 1410 | mem_ref_loc aref; |
15d19bf8 RB |
1411 | aref.stmt = stmt; |
1412 | aref.ref = loc; | |
32500433 RB |
1413 | ref->accesses_in_loop.safe_push (aref); |
1414 | } | |
1415 | ||
1416 | /* Set the LOOP bit in REF stored bitmap and allocate that if | |
1417 | necessary. Return whether a bit was changed. */ | |
1418 | ||
1419 | static bool | |
99b1c316 | 1420 | set_ref_stored_in_loop (im_mem_ref *ref, class loop *loop) |
32500433 RB |
1421 | { |
1422 | if (!ref->stored) | |
1423 | ref->stored = BITMAP_ALLOC (&lim_bitmap_obstack); | |
1424 | return bitmap_set_bit (ref->stored, loop->num); | |
a7e5372d ZD |
1425 | } |
1426 | ||
72425608 | 1427 | /* Marks reference REF as stored in LOOP. */ |
a7e5372d ZD |
1428 | |
1429 | static void | |
99b1c316 | 1430 | mark_ref_stored (im_mem_ref *ref, class loop *loop) |
a7e5372d | 1431 | { |
374001cb | 1432 | while (loop != current_loops->tree_root |
32500433 | 1433 | && set_ref_stored_in_loop (ref, loop)) |
374001cb | 1434 | loop = loop_outer (loop); |
72425608 ZD |
1435 | } |
1436 | ||
1437 | /* Gathers memory references in statement STMT in LOOP, storing the | |
1438 | information about them in the memory_accesses structure. Marks | |
1439 | the vops accessed through unrecognized statements there as | |
1440 | well. */ | |
1441 | ||
1442 | static void | |
99b1c316 | 1443 | gather_mem_refs_stmt (class loop *loop, gimple *stmt) |
72425608 ZD |
1444 | { |
1445 | tree *mem = NULL; | |
1446 | hashval_t hash; | |
46842bfe | 1447 | im_mem_ref **slot; |
61baec41 | 1448 | im_mem_ref *ref; |
72425608 | 1449 | bool is_stored; |
72425608 | 1450 | unsigned id; |
a7e5372d | 1451 | |
5006671f | 1452 | if (!gimple_vuse (stmt)) |
72425608 ZD |
1453 | return; |
1454 | ||
1455 | mem = simple_mem_ref_in_stmt (stmt, &is_stored); | |
1456 | if (!mem) | |
546d314c | 1457 | { |
e6647190 RB |
1458 | /* We use the shared mem_ref for all unanalyzable refs. */ |
1459 | id = UNANALYZABLE_MEM_ID; | |
1460 | ref = memory_accesses.refs_list[id]; | |
546d314c RG |
1461 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1462 | { | |
1463 | fprintf (dump_file, "Unanalyzed memory reference %u: ", id); | |
1464 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1465 | } | |
e6647190 | 1466 | is_stored = gimple_vdef (stmt); |
72425608 ZD |
1467 | } |
1468 | else | |
a7e5372d | 1469 | { |
1c852d1d RB |
1470 | /* We are looking for equal refs that might differ in structure |
1471 | such as a.b vs. MEM[&a + 4]. So we key off the ao_ref but | |
1472 | make sure we can canonicalize the ref in the hashtable if | |
1473 | non-operand_equal_p refs are found. For the lookup we mark | |
1474 | the case we want strict equality with aor.max_size == -1. */ | |
1475 | ao_ref aor; | |
1476 | ao_ref_init (&aor, *mem); | |
1477 | ao_ref_base (&aor); | |
1478 | ao_ref_alias_set (&aor); | |
1479 | HOST_WIDE_INT offset, size, max_size; | |
1480 | poly_int64 saved_maxsize = aor.max_size, mem_off; | |
1481 | tree mem_base; | |
a8aa828b | 1482 | bool ref_decomposed; |
1c852d1d RB |
1483 | if (aor.max_size_known_p () |
1484 | && aor.offset.is_constant (&offset) | |
4c3643a5 RB |
1485 | && aor.size.is_constant (&size) |
1486 | && aor.max_size.is_constant (&max_size) | |
1c852d1d | 1487 | && size == max_size |
4c3643a5 | 1488 | && (size % BITS_PER_UNIT) == 0 |
79977c82 RB |
1489 | /* We're canonicalizing to a MEM where TYPE_SIZE specifies the |
1490 | size. Make sure this is consistent with the extraction. */ | |
1491 | && poly_int_tree_p (TYPE_SIZE (TREE_TYPE (*mem))) | |
1492 | && known_eq (wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (*mem))), | |
1493 | aor.size) | |
1c852d1d RB |
1494 | && (mem_base = get_addr_base_and_unit_offset (aor.ref, &mem_off))) |
1495 | { | |
a8aa828b | 1496 | ref_decomposed = true; |
1c852d1d RB |
1497 | hash = iterative_hash_expr (ao_ref_base (&aor), 0); |
1498 | hash = iterative_hash_host_wide_int (offset, hash); | |
1499 | hash = iterative_hash_host_wide_int (size, hash); | |
1500 | } | |
1501 | else | |
1502 | { | |
a8aa828b | 1503 | ref_decomposed = false; |
1c852d1d RB |
1504 | hash = iterative_hash_expr (aor.ref, 0); |
1505 | aor.max_size = -1; | |
1506 | } | |
1507 | slot = memory_accesses.refs->find_slot_with_hash (&aor, hash, INSERT); | |
1508 | aor.max_size = saved_maxsize; | |
e6647190 | 1509 | if (*slot) |
72425608 | 1510 | { |
1c852d1d RB |
1511 | if (!(*slot)->ref_canonical |
1512 | && !operand_equal_p (*mem, (*slot)->mem.ref, 0)) | |
1513 | { | |
1514 | /* If we didn't yet canonicalize the hashtable ref (which | |
1515 | we'll end up using for code insertion) and hit a second | |
1516 | equal ref that is not structurally equivalent create | |
1517 | a canonical ref which is a bare MEM_REF. */ | |
1518 | if (TREE_CODE (*mem) == MEM_REF | |
1519 | || TREE_CODE (*mem) == TARGET_MEM_REF) | |
1520 | { | |
1521 | (*slot)->mem.ref = *mem; | |
1522 | (*slot)->mem.base_alias_set = ao_ref_base_alias_set (&aor); | |
1523 | } | |
1524 | else | |
1525 | { | |
1526 | tree ref_alias_type = reference_alias_ptr_type (*mem); | |
1527 | unsigned int ref_align = get_object_alignment (*mem); | |
1528 | tree ref_type = TREE_TYPE (*mem); | |
1529 | tree tmp = build_fold_addr_expr (unshare_expr (mem_base)); | |
1530 | if (TYPE_ALIGN (ref_type) != ref_align) | |
1531 | ref_type = build_aligned_type (ref_type, ref_align); | |
1532 | (*slot)->mem.ref | |
1533 | = fold_build2 (MEM_REF, ref_type, tmp, | |
1534 | build_int_cst (ref_alias_type, mem_off)); | |
1535 | if ((*slot)->mem.volatile_p) | |
1536 | TREE_THIS_VOLATILE ((*slot)->mem.ref) = 1; | |
1537 | gcc_checking_assert (TREE_CODE ((*slot)->mem.ref) == MEM_REF | |
1538 | && is_gimple_mem_ref_addr | |
1539 | (TREE_OPERAND ((*slot)->mem.ref, | |
1540 | 0))); | |
1541 | (*slot)->mem.base_alias_set = (*slot)->mem.ref_alias_set; | |
1542 | } | |
1543 | (*slot)->ref_canonical = true; | |
1544 | } | |
61baec41 | 1545 | ref = *slot; |
e6647190 | 1546 | id = ref->id; |
72425608 | 1547 | } |
e6647190 RB |
1548 | else |
1549 | { | |
1550 | id = memory_accesses.refs_list.length (); | |
1c852d1d | 1551 | ref = mem_ref_alloc (&aor, hash, id); |
a8aa828b | 1552 | ref->ref_decomposed = ref_decomposed; |
e6647190 RB |
1553 | memory_accesses.refs_list.safe_push (ref); |
1554 | *slot = ref; | |
039496da | 1555 | |
e6647190 RB |
1556 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1557 | { | |
1558 | fprintf (dump_file, "Memory reference %u: ", id); | |
1559 | print_generic_expr (dump_file, ref->mem.ref, TDF_SLIM); | |
1560 | fprintf (dump_file, "\n"); | |
1561 | } | |
1562 | } | |
1563 | ||
32500433 | 1564 | record_mem_ref_loc (ref, stmt, mem); |
e6647190 | 1565 | } |
374001cb | 1566 | bitmap_set_bit (&memory_accesses.refs_in_loop[loop->num], ref->id); |
72425608 | 1567 | if (is_stored) |
c00217fc | 1568 | { |
374001cb | 1569 | bitmap_set_bit (&memory_accesses.refs_stored_in_loop[loop->num], ref->id); |
c00217fc RB |
1570 | mark_ref_stored (ref, loop); |
1571 | } | |
5164293a | 1572 | init_lim_data (stmt)->ref = ref->id; |
72425608 | 1573 | return; |
a7e5372d ZD |
1574 | } |
1575 | ||
5a2d2a79 RB |
1576 | static unsigned *bb_loop_postorder; |
1577 | ||
1578 | /* qsort sort function to sort blocks after their loop fathers postorder. */ | |
1579 | ||
1580 | static int | |
8c228993 RB |
1581 | sort_bbs_in_loop_postorder_cmp (const void *bb1_, const void *bb2_, |
1582 | void *bb_loop_postorder_) | |
5a2d2a79 | 1583 | { |
8c228993 | 1584 | unsigned *bb_loop_postorder = (unsigned *)bb_loop_postorder_; |
06b4c6d2 AM |
1585 | basic_block bb1 = *(const basic_block *)bb1_; |
1586 | basic_block bb2 = *(const basic_block *)bb2_; | |
99b1c316 MS |
1587 | class loop *loop1 = bb1->loop_father; |
1588 | class loop *loop2 = bb2->loop_father; | |
5a2d2a79 | 1589 | if (loop1->num == loop2->num) |
5804f627 | 1590 | return bb1->index - bb2->index; |
5a2d2a79 RB |
1591 | return bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num] ? -1 : 1; |
1592 | } | |
1593 | ||
32500433 RB |
1594 | /* qsort sort function to sort ref locs after their loop fathers postorder. */ |
1595 | ||
1596 | static int | |
8c228993 RB |
1597 | sort_locs_in_loop_postorder_cmp (const void *loc1_, const void *loc2_, |
1598 | void *bb_loop_postorder_) | |
32500433 | 1599 | { |
8c228993 | 1600 | unsigned *bb_loop_postorder = (unsigned *)bb_loop_postorder_; |
06b4c6d2 AM |
1601 | const mem_ref_loc *loc1 = (const mem_ref_loc *)loc1_; |
1602 | const mem_ref_loc *loc2 = (const mem_ref_loc *)loc2_; | |
99b1c316 MS |
1603 | class loop *loop1 = gimple_bb (loc1->stmt)->loop_father; |
1604 | class loop *loop2 = gimple_bb (loc2->stmt)->loop_father; | |
32500433 RB |
1605 | if (loop1->num == loop2->num) |
1606 | return 0; | |
1607 | return bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num] ? -1 : 1; | |
1608 | } | |
1609 | ||
72425608 | 1610 | /* Gathers memory references in loops. */ |
a7e5372d ZD |
1611 | |
1612 | static void | |
374001cb | 1613 | analyze_memory_references (void) |
a7e5372d | 1614 | { |
726a989a | 1615 | gimple_stmt_iterator bsi; |
5a2d2a79 | 1616 | basic_block bb, *bbs; |
99b1c316 | 1617 | class loop *loop, *outer; |
5a2d2a79 | 1618 | unsigned i, n; |
72425608 | 1619 | |
5a2d2a79 RB |
1620 | /* Collect all basic-blocks in loops and sort them after their |
1621 | loops postorder. */ | |
1622 | i = 0; | |
0cae8d31 | 1623 | bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS); |
11cd3bed | 1624 | FOR_EACH_BB_FN (bb, cfun) |
5a2d2a79 RB |
1625 | if (bb->loop_father != current_loops->tree_root) |
1626 | bbs[i++] = bb; | |
1627 | n = i; | |
8c228993 RB |
1628 | gcc_sort_r (bbs, n, sizeof (basic_block), sort_bbs_in_loop_postorder_cmp, |
1629 | bb_loop_postorder); | |
5a2d2a79 RB |
1630 | |
1631 | /* Visit blocks in loop postorder and assign mem-ref IDs in that order. | |
1632 | That results in better locality for all the bitmaps. */ | |
1633 | for (i = 0; i < n; ++i) | |
72425608 | 1634 | { |
5a2d2a79 | 1635 | basic_block bb = bbs[i]; |
726a989a | 1636 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
5a2d2a79 | 1637 | gather_mem_refs_stmt (bb->loop_father, gsi_stmt (bsi)); |
72425608 ZD |
1638 | } |
1639 | ||
32500433 RB |
1640 | /* Sort the location list of gathered memory references after their |
1641 | loop postorder number. */ | |
46842bfe | 1642 | im_mem_ref *ref; |
32500433 | 1643 | FOR_EACH_VEC_ELT (memory_accesses.refs_list, i, ref) |
8c228993 RB |
1644 | ref->accesses_in_loop.sort (sort_locs_in_loop_postorder_cmp, |
1645 | bb_loop_postorder); | |
32500433 | 1646 | |
5a2d2a79 RB |
1647 | free (bbs); |
1648 | ||
546d314c RG |
1649 | /* Propagate the information about accessed memory references up |
1650 | the loop hierarchy. */ | |
f0bd40b1 | 1651 | FOR_EACH_LOOP (loop, LI_FROM_INNERMOST) |
72425608 | 1652 | { |
c00217fc | 1653 | /* Finalize the overall touched references (including subloops). */ |
374001cb RB |
1654 | bitmap_ior_into (&memory_accesses.all_refs_stored_in_loop[loop->num], |
1655 | &memory_accesses.refs_stored_in_loop[loop->num]); | |
c00217fc RB |
1656 | |
1657 | /* Propagate the information about accessed memory references up | |
1658 | the loop hierarchy. */ | |
1659 | outer = loop_outer (loop); | |
1660 | if (outer == current_loops->tree_root) | |
72425608 ZD |
1661 | continue; |
1662 | ||
374001cb RB |
1663 | bitmap_ior_into (&memory_accesses.all_refs_stored_in_loop[outer->num], |
1664 | &memory_accesses.all_refs_stored_in_loop[loop->num]); | |
72425608 | 1665 | } |
72425608 ZD |
1666 | } |
1667 | ||
72425608 ZD |
1668 | /* Returns true if MEM1 and MEM2 may alias. TTAE_CACHE is used as a cache in |
1669 | tree_to_aff_combination_expand. */ | |
1670 | ||
1671 | static bool | |
61baec41 | 1672 | mem_refs_may_alias_p (im_mem_ref *mem1, im_mem_ref *mem2, |
39c8aaa4 | 1673 | hash_map<tree, name_expansion *> **ttae_cache) |
72425608 ZD |
1674 | { |
1675 | /* Perform BASE + OFFSET analysis -- if MEM1 and MEM2 are based on the same | |
1676 | object and their offset differ in such a way that the locations cannot | |
1677 | overlap, then they cannot alias. */ | |
a85d87b2 | 1678 | poly_widest_int size1, size2; |
1842e4d4 | 1679 | aff_tree off1, off2; |
72425608 | 1680 | |
1842e4d4 | 1681 | /* Perform basic offset and type-based disambiguation. */ |
bdb01696 | 1682 | if (!refs_may_alias_p_1 (&mem1->mem, &mem2->mem, true)) |
72425608 | 1683 | return false; |
a7e5372d | 1684 | |
72425608 ZD |
1685 | /* The expansion of addresses may be a bit expensive, thus we only do |
1686 | the check at -O2 and higher optimization levels. */ | |
1687 | if (optimize < 2) | |
1688 | return true; | |
1689 | ||
bdb01696 RB |
1690 | get_inner_reference_aff (mem1->mem.ref, &off1, &size1); |
1691 | get_inner_reference_aff (mem2->mem.ref, &off2, &size2); | |
72425608 ZD |
1692 | aff_combination_expand (&off1, ttae_cache); |
1693 | aff_combination_expand (&off2, ttae_cache); | |
807e902e | 1694 | aff_combination_scale (&off1, -1); |
72425608 ZD |
1695 | aff_combination_add (&off2, &off1); |
1696 | ||
02f5d6c5 | 1697 | if (aff_comb_cannot_overlap_p (&off2, size1, size2)) |
72425608 ZD |
1698 | return false; |
1699 | ||
1700 | return true; | |
1701 | } | |
1702 | ||
32500433 RB |
1703 | /* Compare function for bsearch searching for reference locations |
1704 | in a loop. */ | |
1705 | ||
1706 | static int | |
8c228993 RB |
1707 | find_ref_loc_in_loop_cmp (const void *loop_, const void *loc_, |
1708 | void *bb_loop_postorder_) | |
32500433 | 1709 | { |
8c228993 | 1710 | unsigned *bb_loop_postorder = (unsigned *)bb_loop_postorder_; |
99b1c316 | 1711 | class loop *loop = (class loop *)const_cast<void *>(loop_); |
32500433 | 1712 | mem_ref_loc *loc = (mem_ref_loc *)const_cast<void *>(loc_); |
99b1c316 | 1713 | class loop *loc_loop = gimple_bb (loc->stmt)->loop_father; |
32500433 RB |
1714 | if (loop->num == loc_loop->num |
1715 | || flow_loop_nested_p (loop, loc_loop)) | |
1716 | return 0; | |
1717 | return (bb_loop_postorder[loop->num] < bb_loop_postorder[loc_loop->num] | |
1718 | ? -1 : 1); | |
1719 | } | |
1720 | ||
15d19bf8 RB |
1721 | /* Iterates over all locations of REF in LOOP and its subloops calling |
1722 | fn.operator() with the location as argument. When that operator | |
1723 | returns true the iteration is stopped and true is returned. | |
1724 | Otherwise false is returned. */ | |
72425608 | 1725 | |
15d19bf8 RB |
1726 | template <typename FN> |
1727 | static bool | |
99b1c316 | 1728 | for_all_locs_in_loop (class loop *loop, im_mem_ref *ref, FN fn) |
72425608 | 1729 | { |
72425608 | 1730 | unsigned i; |
61baec41 | 1731 | mem_ref_loc *loc; |
72425608 | 1732 | |
32500433 RB |
1733 | /* Search for the cluster of locs in the accesses_in_loop vector |
1734 | which is sorted after postorder index of the loop father. */ | |
8c228993 RB |
1735 | loc = ref->accesses_in_loop.bsearch (loop, find_ref_loc_in_loop_cmp, |
1736 | bb_loop_postorder); | |
32500433 RB |
1737 | if (!loc) |
1738 | return false; | |
72425608 | 1739 | |
32500433 RB |
1740 | /* We have found one location inside loop or its sub-loops. Iterate |
1741 | both forward and backward to cover the whole cluster. */ | |
1742 | i = loc - ref->accesses_in_loop.address (); | |
1743 | while (i > 0) | |
1744 | { | |
1745 | --i; | |
61baec41 | 1746 | mem_ref_loc *l = &ref->accesses_in_loop[i]; |
32500433 RB |
1747 | if (!flow_bb_inside_loop_p (loop, gimple_bb (l->stmt))) |
1748 | break; | |
1749 | if (fn (l)) | |
1750 | return true; | |
1751 | } | |
1752 | for (i = loc - ref->accesses_in_loop.address (); | |
1753 | i < ref->accesses_in_loop.length (); ++i) | |
1754 | { | |
61baec41 | 1755 | mem_ref_loc *l = &ref->accesses_in_loop[i]; |
32500433 RB |
1756 | if (!flow_bb_inside_loop_p (loop, gimple_bb (l->stmt))) |
1757 | break; | |
1758 | if (fn (l)) | |
1759 | return true; | |
1760 | } | |
15d19bf8 RB |
1761 | |
1762 | return false; | |
1763 | } | |
1764 | ||
1765 | /* Rewrites location LOC by TMP_VAR. */ | |
1766 | ||
6c1dae73 | 1767 | class rewrite_mem_ref_loc |
15d19bf8 | 1768 | { |
6c1dae73 | 1769 | public: |
15d19bf8 | 1770 | rewrite_mem_ref_loc (tree tmp_var_) : tmp_var (tmp_var_) {} |
61baec41 | 1771 | bool operator () (mem_ref_loc *loc); |
15d19bf8 RB |
1772 | tree tmp_var; |
1773 | }; | |
1774 | ||
1775 | bool | |
61baec41 | 1776 | rewrite_mem_ref_loc::operator () (mem_ref_loc *loc) |
15d19bf8 RB |
1777 | { |
1778 | *loc->ref = tmp_var; | |
1779 | update_stmt (loc->stmt); | |
1780 | return false; | |
72425608 ZD |
1781 | } |
1782 | ||
1783 | /* Rewrites all references to REF in LOOP by variable TMP_VAR. */ | |
1784 | ||
1785 | static void | |
99b1c316 | 1786 | rewrite_mem_refs (class loop *loop, im_mem_ref *ref, tree tmp_var) |
72425608 | 1787 | { |
15d19bf8 | 1788 | for_all_locs_in_loop (loop, ref, rewrite_mem_ref_loc (tmp_var)); |
a7e5372d ZD |
1789 | } |
1790 | ||
9fd9ccf7 RB |
1791 | /* Stores the first reference location in LOCP. */ |
1792 | ||
6c1dae73 | 1793 | class first_mem_ref_loc_1 |
9fd9ccf7 | 1794 | { |
6c1dae73 | 1795 | public: |
61baec41 TS |
1796 | first_mem_ref_loc_1 (mem_ref_loc **locp_) : locp (locp_) {} |
1797 | bool operator () (mem_ref_loc *loc); | |
1798 | mem_ref_loc **locp; | |
9fd9ccf7 RB |
1799 | }; |
1800 | ||
1801 | bool | |
61baec41 | 1802 | first_mem_ref_loc_1::operator () (mem_ref_loc *loc) |
9fd9ccf7 RB |
1803 | { |
1804 | *locp = loc; | |
1805 | return true; | |
1806 | } | |
1807 | ||
1808 | /* Returns the first reference location to REF in LOOP. */ | |
1809 | ||
61baec41 | 1810 | static mem_ref_loc * |
99b1c316 | 1811 | first_mem_ref_loc (class loop *loop, im_mem_ref *ref) |
9fd9ccf7 | 1812 | { |
61baec41 | 1813 | mem_ref_loc *locp = NULL; |
9fd9ccf7 RB |
1814 | for_all_locs_in_loop (loop, ref, first_mem_ref_loc_1 (&locp)); |
1815 | return locp; | |
1816 | } | |
1817 | ||
039496da AH |
1818 | struct prev_flag_edges { |
1819 | /* Edge to insert new flag comparison code. */ | |
1820 | edge append_cond_position; | |
1821 | ||
1822 | /* Edge for fall through from previous flag comparison. */ | |
1823 | edge last_cond_fallthru; | |
1824 | }; | |
1825 | ||
1826 | /* Helper function for execute_sm. Emit code to store TMP_VAR into | |
1827 | MEM along edge EX. | |
1828 | ||
1829 | The store is only done if MEM has changed. We do this so no | |
1830 | changes to MEM occur on code paths that did not originally store | |
1831 | into it. | |
1832 | ||
1833 | The common case for execute_sm will transform: | |
1834 | ||
1835 | for (...) { | |
1836 | if (foo) | |
1837 | stuff; | |
1838 | else | |
1839 | MEM = TMP_VAR; | |
1840 | } | |
1841 | ||
1842 | into: | |
1843 | ||
1844 | lsm = MEM; | |
1845 | for (...) { | |
1846 | if (foo) | |
1847 | stuff; | |
1848 | else | |
1849 | lsm = TMP_VAR; | |
1850 | } | |
1851 | MEM = lsm; | |
1852 | ||
1853 | This function will generate: | |
1854 | ||
1855 | lsm = MEM; | |
1856 | ||
1857 | lsm_flag = false; | |
1858 | ... | |
1859 | for (...) { | |
1860 | if (foo) | |
1861 | stuff; | |
1862 | else { | |
1863 | lsm = TMP_VAR; | |
1864 | lsm_flag = true; | |
1865 | } | |
1866 | } | |
1867 | if (lsm_flag) <-- | |
1868 | MEM = lsm; <-- | |
1869 | */ | |
1870 | ||
1871 | static void | |
d91561cb JH |
1872 | execute_sm_if_changed (edge ex, tree mem, tree tmp_var, tree flag, |
1873 | edge preheader, hash_set <basic_block> *flag_bbs) | |
039496da AH |
1874 | { |
1875 | basic_block new_bb, then_bb, old_dest; | |
1876 | bool loop_has_only_one_exit; | |
1877 | edge then_old_edge, orig_ex = ex; | |
1878 | gimple_stmt_iterator gsi; | |
355fe088 | 1879 | gimple *stmt; |
039496da | 1880 | struct prev_flag_edges *prev_edges = (struct prev_flag_edges *) ex->aux; |
22718afe | 1881 | bool irr = ex->flags & EDGE_IRREDUCIBLE_LOOP; |
039496da | 1882 | |
d91561cb JH |
1883 | profile_count count_sum = profile_count::zero (); |
1884 | int nbbs = 0, ncount = 0; | |
357067f2 | 1885 | profile_probability flag_probability = profile_probability::uninitialized (); |
d91561cb JH |
1886 | |
1887 | /* Flag is set in FLAG_BBS. Determine probability that flag will be true | |
1888 | at loop exit. | |
1889 | ||
67914693 | 1890 | This code may look fancy, but it cannot update profile very realistically |
d91561cb JH |
1891 | because we do not know the probability that flag will be true at given |
1892 | loop exit. | |
1893 | ||
1894 | We look for two interesting extremes | |
1895 | - when exit is dominated by block setting the flag, we know it will | |
1896 | always be true. This is a common case. | |
1897 | - when all blocks setting the flag have very low frequency we know | |
1898 | it will likely be false. | |
1899 | In all other cases we default to 2/3 for flag being true. */ | |
1900 | ||
1901 | for (hash_set<basic_block>::iterator it = flag_bbs->begin (); | |
1902 | it != flag_bbs->end (); ++it) | |
1903 | { | |
d91561cb JH |
1904 | if ((*it)->count.initialized_p ()) |
1905 | count_sum += (*it)->count, ncount ++; | |
1906 | if (dominated_by_p (CDI_DOMINATORS, ex->src, *it)) | |
357067f2 | 1907 | flag_probability = profile_probability::always (); |
d91561cb JH |
1908 | nbbs++; |
1909 | } | |
1910 | ||
357067f2 JH |
1911 | profile_probability cap = profile_probability::always ().apply_scale (2, 3); |
1912 | ||
1913 | if (flag_probability.initialized_p ()) | |
d91561cb | 1914 | ; |
e7a74006 JH |
1915 | else if (ncount == nbbs |
1916 | && preheader->count () >= count_sum && preheader->count ().nonzero_p ()) | |
d91561cb | 1917 | { |
ef30ab83 | 1918 | flag_probability = count_sum.probability_in (preheader->count ()); |
357067f2 JH |
1919 | if (flag_probability > cap) |
1920 | flag_probability = cap; | |
d91561cb | 1921 | } |
e7a74006 JH |
1922 | |
1923 | if (!flag_probability.initialized_p ()) | |
357067f2 | 1924 | flag_probability = cap; |
d91561cb | 1925 | |
039496da AH |
1926 | /* ?? Insert store after previous store if applicable. See note |
1927 | below. */ | |
1928 | if (prev_edges) | |
1929 | ex = prev_edges->append_cond_position; | |
1930 | ||
1931 | loop_has_only_one_exit = single_pred_p (ex->dest); | |
1932 | ||
1933 | if (loop_has_only_one_exit) | |
1934 | ex = split_block_after_labels (ex->dest); | |
4f912f91 RB |
1935 | else |
1936 | { | |
1937 | for (gphi_iterator gpi = gsi_start_phis (ex->dest); | |
1938 | !gsi_end_p (gpi); gsi_next (&gpi)) | |
1939 | { | |
1940 | gphi *phi = gpi.phi (); | |
1941 | if (virtual_operand_p (gimple_phi_result (phi))) | |
1942 | continue; | |
1943 | ||
1944 | /* When the destination has a non-virtual PHI node with multiple | |
1945 | predecessors make sure we preserve the PHI structure by | |
1946 | forcing a forwarder block so that hoisting of that PHI will | |
1947 | still work. */ | |
1948 | split_edge (ex); | |
1949 | break; | |
1950 | } | |
1951 | } | |
039496da AH |
1952 | |
1953 | old_dest = ex->dest; | |
1954 | new_bb = split_edge (ex); | |
1955 | then_bb = create_empty_bb (new_bb); | |
d91561cb | 1956 | then_bb->count = new_bb->count.apply_probability (flag_probability); |
22718afe RB |
1957 | if (irr) |
1958 | then_bb->flags = BB_IRREDUCIBLE_LOOP; | |
1959 | add_bb_to_loop (then_bb, new_bb->loop_father); | |
039496da AH |
1960 | |
1961 | gsi = gsi_start_bb (new_bb); | |
1962 | stmt = gimple_build_cond (NE_EXPR, flag, boolean_false_node, | |
1963 | NULL_TREE, NULL_TREE); | |
1964 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1965 | ||
1966 | gsi = gsi_start_bb (then_bb); | |
1967 | /* Insert actual store. */ | |
1968 | stmt = gimple_build_assign (unshare_expr (mem), tmp_var); | |
1969 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1970 | ||
d91561cb JH |
1971 | edge e1 = single_succ_edge (new_bb); |
1972 | edge e2 = make_edge (new_bb, then_bb, | |
1973 | EDGE_TRUE_VALUE | (irr ? EDGE_IRREDUCIBLE_LOOP : 0)); | |
1974 | e2->probability = flag_probability; | |
d91561cb JH |
1975 | |
1976 | e1->flags |= EDGE_FALSE_VALUE | (irr ? EDGE_IRREDUCIBLE_LOOP : 0); | |
1977 | e1->flags &= ~EDGE_FALLTHRU; | |
1978 | ||
357067f2 | 1979 | e1->probability = flag_probability.invert (); |
d91561cb | 1980 | |
357067f2 | 1981 | then_old_edge = make_single_succ_edge (then_bb, old_dest, |
22718afe | 1982 | EDGE_FALLTHRU | (irr ? EDGE_IRREDUCIBLE_LOOP : 0)); |
039496da AH |
1983 | |
1984 | set_immediate_dominator (CDI_DOMINATORS, then_bb, new_bb); | |
1985 | ||
1986 | if (prev_edges) | |
1987 | { | |
1988 | basic_block prevbb = prev_edges->last_cond_fallthru->src; | |
1989 | redirect_edge_succ (prev_edges->last_cond_fallthru, new_bb); | |
1990 | set_immediate_dominator (CDI_DOMINATORS, new_bb, prevbb); | |
1991 | set_immediate_dominator (CDI_DOMINATORS, old_dest, | |
1992 | recompute_dominator (CDI_DOMINATORS, old_dest)); | |
1993 | } | |
1994 | ||
1995 | /* ?? Because stores may alias, they must happen in the exact | |
1996 | sequence they originally happened. Save the position right after | |
1997 | the (_lsm) store we just created so we can continue appending after | |
1998 | it and maintain the original order. */ | |
1999 | { | |
2000 | struct prev_flag_edges *p; | |
2001 | ||
2002 | if (orig_ex->aux) | |
2003 | orig_ex->aux = NULL; | |
2004 | alloc_aux_for_edge (orig_ex, sizeof (struct prev_flag_edges)); | |
2005 | p = (struct prev_flag_edges *) orig_ex->aux; | |
2006 | p->append_cond_position = then_old_edge; | |
2007 | p->last_cond_fallthru = find_edge (new_bb, old_dest); | |
2008 | orig_ex->aux = (void *) p; | |
2009 | } | |
2010 | ||
2011 | if (!loop_has_only_one_exit) | |
538dd0b7 DM |
2012 | for (gphi_iterator gpi = gsi_start_phis (old_dest); |
2013 | !gsi_end_p (gpi); gsi_next (&gpi)) | |
039496da | 2014 | { |
538dd0b7 | 2015 | gphi *phi = gpi.phi (); |
039496da AH |
2016 | unsigned i; |
2017 | ||
2018 | for (i = 0; i < gimple_phi_num_args (phi); i++) | |
2019 | if (gimple_phi_arg_edge (phi, i)->src == new_bb) | |
2020 | { | |
2021 | tree arg = gimple_phi_arg_def (phi, i); | |
9e227d60 | 2022 | add_phi_arg (phi, arg, then_old_edge, UNKNOWN_LOCATION); |
039496da AH |
2023 | update_stmt (phi); |
2024 | } | |
2025 | } | |
039496da AH |
2026 | } |
2027 | ||
15d19bf8 RB |
2028 | /* When REF is set on the location, set flag indicating the store. */ |
2029 | ||
6c1dae73 | 2030 | class sm_set_flag_if_changed |
15d19bf8 | 2031 | { |
6c1dae73 | 2032 | public: |
d91561cb JH |
2033 | sm_set_flag_if_changed (tree flag_, hash_set <basic_block> *bbs_) |
2034 | : flag (flag_), bbs (bbs_) {} | |
61baec41 | 2035 | bool operator () (mem_ref_loc *loc); |
15d19bf8 | 2036 | tree flag; |
d91561cb | 2037 | hash_set <basic_block> *bbs; |
15d19bf8 RB |
2038 | }; |
2039 | ||
2040 | bool | |
61baec41 | 2041 | sm_set_flag_if_changed::operator () (mem_ref_loc *loc) |
15d19bf8 RB |
2042 | { |
2043 | /* Only set the flag for writes. */ | |
2044 | if (is_gimple_assign (loc->stmt) | |
2045 | && gimple_assign_lhs_ptr (loc->stmt) == loc->ref) | |
2046 | { | |
2047 | gimple_stmt_iterator gsi = gsi_for_stmt (loc->stmt); | |
355fe088 | 2048 | gimple *stmt = gimple_build_assign (flag, boolean_true_node); |
15d19bf8 | 2049 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); |
d91561cb | 2050 | bbs->add (gimple_bb (stmt)); |
15d19bf8 RB |
2051 | } |
2052 | return false; | |
2053 | } | |
2054 | ||
039496da AH |
2055 | /* Helper function for execute_sm. On every location where REF is |
2056 | set, set an appropriate flag indicating the store. */ | |
2057 | ||
2058 | static tree | |
99b1c316 | 2059 | execute_sm_if_changed_flag_set (class loop *loop, im_mem_ref *ref, |
d91561cb | 2060 | hash_set <basic_block> *bbs) |
039496da | 2061 | { |
039496da | 2062 | tree flag; |
71343877 | 2063 | char *str = get_lsm_tmp_name (ref->mem.ref, ~0, "_flag"); |
7cc434a3 | 2064 | flag = create_tmp_reg (boolean_type_node, str); |
d91561cb | 2065 | for_all_locs_in_loop (loop, ref, sm_set_flag_if_changed (flag, bbs)); |
039496da AH |
2066 | return flag; |
2067 | } | |
2068 | ||
72425608 | 2069 | /* Executes store motion of memory reference REF from LOOP. |
ca83d385 ZD |
2070 | Exits from the LOOP are stored in EXITS. The initialization of the |
2071 | temporary variable is put to the preheader of the loop, and assignments | |
2072 | to the reference from the temporary variable are emitted to exits. */ | |
a7e5372d ZD |
2073 | |
2074 | static void | |
99b1c316 | 2075 | execute_sm (class loop *loop, vec<edge> exits, im_mem_ref *ref) |
a7e5372d | 2076 | { |
32500433 | 2077 | tree tmp_var, store_flag = NULL_TREE; |
a7e5372d | 2078 | unsigned i; |
538dd0b7 | 2079 | gassign *load; |
b4042a03 | 2080 | struct fmt_data fmt_data; |
9fd9ccf7 | 2081 | edge ex; |
726a989a | 2082 | struct lim_aux_data *lim_data; |
039496da | 2083 | bool multi_threaded_model_p = false; |
9fd9ccf7 | 2084 | gimple_stmt_iterator gsi; |
d91561cb | 2085 | hash_set<basic_block> flag_bbs; |
a7e5372d | 2086 | |
a3631d97 ZD |
2087 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2088 | { | |
2089 | fprintf (dump_file, "Executing store motion of "); | |
ef6cb4c7 | 2090 | print_generic_expr (dump_file, ref->mem.ref); |
a3631d97 ZD |
2091 | fprintf (dump_file, " from loop %d\n", loop->num); |
2092 | } | |
2093 | ||
bdb01696 RB |
2094 | tmp_var = create_tmp_reg (TREE_TYPE (ref->mem.ref), |
2095 | get_lsm_tmp_name (ref->mem.ref, ~0)); | |
a7e5372d | 2096 | |
b4042a03 ZD |
2097 | fmt_data.loop = loop; |
2098 | fmt_data.orig_loop = loop; | |
bdb01696 | 2099 | for_each_index (&ref->mem.ref, force_move_till, &fmt_data); |
a7e5372d | 2100 | |
7783daa7 | 2101 | if (bb_in_transaction (loop_preheader_edge (loop)->src) |
e622a32d | 2102 | || (! flag_store_data_races |
2866f21d | 2103 | && ! ref_always_accessed_p (loop, ref, true))) |
039496da AH |
2104 | multi_threaded_model_p = true; |
2105 | ||
2106 | if (multi_threaded_model_p) | |
d91561cb | 2107 | store_flag = execute_sm_if_changed_flag_set (loop, ref, &flag_bbs); |
039496da | 2108 | |
72425608 | 2109 | rewrite_mem_refs (loop, ref, tmp_var); |
a7e5372d | 2110 | |
9fd9ccf7 RB |
2111 | /* Emit the load code on a random exit edge or into the latch if |
2112 | the loop does not exit, so that we are sure it will be processed | |
2113 | by move_computations after all dependencies. */ | |
2114 | gsi = gsi_for_stmt (first_mem_ref_loc (loop, ref)->stmt); | |
039496da AH |
2115 | |
2116 | /* FIXME/TODO: For the multi-threaded variant, we could avoid this | |
2117 | load altogether, since the store is predicated by a flag. We | |
2118 | could, do the load only if it was originally in the loop. */ | |
bdb01696 | 2119 | load = gimple_build_assign (tmp_var, unshare_expr (ref->mem.ref)); |
726a989a RB |
2120 | lim_data = init_lim_data (load); |
2121 | lim_data->max_loop = loop; | |
2122 | lim_data->tgt_loop = loop; | |
9fd9ccf7 | 2123 | gsi_insert_before (&gsi, load, GSI_SAME_STMT); |
a7e5372d | 2124 | |
039496da | 2125 | if (multi_threaded_model_p) |
a7e5372d | 2126 | { |
039496da AH |
2127 | load = gimple_build_assign (store_flag, boolean_false_node); |
2128 | lim_data = init_lim_data (load); | |
2129 | lim_data->max_loop = loop; | |
2130 | lim_data->tgt_loop = loop; | |
9fd9ccf7 | 2131 | gsi_insert_before (&gsi, load, GSI_SAME_STMT); |
a7e5372d | 2132 | } |
039496da AH |
2133 | |
2134 | /* Sink the store to every exit from the loop. */ | |
9771b263 | 2135 | FOR_EACH_VEC_ELT (exits, i, ex) |
039496da AH |
2136 | if (!multi_threaded_model_p) |
2137 | { | |
538dd0b7 | 2138 | gassign *store; |
bdb01696 | 2139 | store = gimple_build_assign (unshare_expr (ref->mem.ref), tmp_var); |
039496da AH |
2140 | gsi_insert_on_edge (ex, store); |
2141 | } | |
2142 | else | |
d91561cb JH |
2143 | execute_sm_if_changed (ex, ref->mem.ref, tmp_var, store_flag, |
2144 | loop_preheader_edge (loop), &flag_bbs); | |
a7e5372d ZD |
2145 | } |
2146 | ||
72425608 ZD |
2147 | /* Hoists memory references MEM_REFS out of LOOP. EXITS is the list of exit |
2148 | edges of the LOOP. */ | |
a7e5372d ZD |
2149 | |
2150 | static void | |
99b1c316 | 2151 | hoist_memory_references (class loop *loop, bitmap mem_refs, |
9771b263 | 2152 | vec<edge> exits) |
a7e5372d | 2153 | { |
61baec41 | 2154 | im_mem_ref *ref; |
72425608 ZD |
2155 | unsigned i; |
2156 | bitmap_iterator bi; | |
a3631d97 | 2157 | |
72425608 | 2158 | EXECUTE_IF_SET_IN_BITMAP (mem_refs, 0, i, bi) |
a7e5372d | 2159 | { |
9771b263 | 2160 | ref = memory_accesses.refs_list[i]; |
72425608 | 2161 | execute_sm (loop, exits, ref); |
a7e5372d | 2162 | } |
01fd257a ZD |
2163 | } |
2164 | ||
6c1dae73 | 2165 | class ref_always_accessed |
15d19bf8 | 2166 | { |
6c1dae73 | 2167 | public: |
99b1c316 | 2168 | ref_always_accessed (class loop *loop_, bool stored_p_) |
32500433 | 2169 | : loop (loop_), stored_p (stored_p_) {} |
61baec41 | 2170 | bool operator () (mem_ref_loc *loc); |
99b1c316 | 2171 | class loop *loop; |
15d19bf8 RB |
2172 | bool stored_p; |
2173 | }; | |
a7e5372d | 2174 | |
15d19bf8 | 2175 | bool |
61baec41 | 2176 | ref_always_accessed::operator () (mem_ref_loc *loc) |
a7e5372d | 2177 | { |
99b1c316 | 2178 | class loop *must_exec; |
58adb739 | 2179 | |
15d19bf8 RB |
2180 | if (!get_lim_data (loc->stmt)) |
2181 | return false; | |
a7e5372d | 2182 | |
15d19bf8 RB |
2183 | /* If we require an always executed store make sure the statement |
2184 | stores to the reference. */ | |
2185 | if (stored_p) | |
72425608 | 2186 | { |
32500433 RB |
2187 | tree lhs = gimple_get_lhs (loc->stmt); |
2188 | if (!lhs | |
2189 | || lhs != *loc->ref) | |
15d19bf8 RB |
2190 | return false; |
2191 | } | |
a7e5372d | 2192 | |
15d19bf8 RB |
2193 | must_exec = get_lim_data (loc->stmt)->always_executed_in; |
2194 | if (!must_exec) | |
2195 | return false; | |
58adb739 | 2196 | |
15d19bf8 RB |
2197 | if (must_exec == loop |
2198 | || flow_loop_nested_p (must_exec, loop)) | |
2199 | return true; | |
a7e5372d | 2200 | |
15d19bf8 RB |
2201 | return false; |
2202 | } | |
01fd257a | 2203 | |
15d19bf8 RB |
2204 | /* Returns true if REF is always accessed in LOOP. If STORED_P is true |
2205 | make sure REF is always stored to in LOOP. */ | |
2206 | ||
2207 | static bool | |
99b1c316 | 2208 | ref_always_accessed_p (class loop *loop, im_mem_ref *ref, bool stored_p) |
15d19bf8 | 2209 | { |
15d19bf8 | 2210 | return for_all_locs_in_loop (loop, ref, |
32500433 | 2211 | ref_always_accessed (loop, stored_p)); |
01fd257a ZD |
2212 | } |
2213 | ||
72425608 | 2214 | /* Returns true if REF1 and REF2 are independent. */ |
01fd257a | 2215 | |
72425608 | 2216 | static bool |
61baec41 | 2217 | refs_independent_p (im_mem_ref *ref1, im_mem_ref *ref2) |
01fd257a | 2218 | { |
bdb01696 | 2219 | if (ref1 == ref2) |
72425608 | 2220 | return true; |
bdb01696 | 2221 | |
72425608 ZD |
2222 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2223 | fprintf (dump_file, "Querying dependency of refs %u and %u: ", | |
2224 | ref1->id, ref2->id); | |
2225 | ||
bdb01696 | 2226 | if (mem_refs_may_alias_p (ref1, ref2, &memory_accesses.ttae_cache)) |
72425608 | 2227 | { |
72425608 ZD |
2228 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2229 | fprintf (dump_file, "dependent.\n"); | |
2230 | return false; | |
2231 | } | |
2232 | else | |
2233 | { | |
72425608 ZD |
2234 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2235 | fprintf (dump_file, "independent.\n"); | |
2236 | return true; | |
2237 | } | |
01fd257a ZD |
2238 | } |
2239 | ||
c00217fc RB |
2240 | /* Mark REF dependent on stores or loads (according to STORED_P) in LOOP |
2241 | and its super-loops. */ | |
01fd257a ZD |
2242 | |
2243 | static void | |
99b1c316 | 2244 | record_dep_loop (class loop *loop, im_mem_ref *ref, bool stored_p) |
01fd257a | 2245 | { |
c00217fc RB |
2246 | /* We can propagate dependent-in-loop bits up the loop |
2247 | hierarchy to all outer loops. */ | |
2248 | while (loop != current_loops->tree_root | |
374001cb | 2249 | && bitmap_set_bit (&ref->dep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
c00217fc | 2250 | loop = loop_outer (loop); |
72425608 | 2251 | } |
01fd257a | 2252 | |
ff4fa993 | 2253 | /* Returns true if REF is independent on all other memory |
bcfaa720 | 2254 | references in LOOP. */ |
01fd257a | 2255 | |
72425608 | 2256 | static bool |
99b1c316 | 2257 | ref_indep_loop_p_1 (class loop *loop, im_mem_ref *ref, bool stored_p) |
72425608 | 2258 | { |
ff4fa993 YR |
2259 | stored_p |= (ref->stored && bitmap_bit_p (ref->stored, loop->num)); |
2260 | ||
ff4fa993 | 2261 | bool indep_p = true; |
546d314c | 2262 | bitmap refs_to_check; |
72425608 | 2263 | |
c00217fc | 2264 | if (stored_p) |
374001cb | 2265 | refs_to_check = &memory_accesses.refs_in_loop[loop->num]; |
546d314c | 2266 | else |
374001cb | 2267 | refs_to_check = &memory_accesses.refs_stored_in_loop[loop->num]; |
01fd257a | 2268 | |
e6647190 | 2269 | if (bitmap_bit_p (refs_to_check, UNANALYZABLE_MEM_ID)) |
ff4fa993 | 2270 | indep_p = false; |
ff4fa993 | 2271 | else |
01fd257a | 2272 | { |
ff4fa993 YR |
2273 | if (bitmap_bit_p (&ref->indep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
2274 | return true; | |
2275 | if (bitmap_bit_p (&ref->dep_loop, LOOP_DEP_BIT (loop->num, stored_p))) | |
c00217fc | 2276 | return false; |
01fd257a | 2277 | |
99b1c316 | 2278 | class loop *inner = loop->inner; |
ff4fa993 YR |
2279 | while (inner) |
2280 | { | |
bcfaa720 | 2281 | if (!ref_indep_loop_p_1 (inner, ref, stored_p)) |
ff4fa993 YR |
2282 | { |
2283 | indep_p = false; | |
2284 | break; | |
2285 | } | |
2286 | inner = inner->next; | |
2287 | } | |
513d866d | 2288 | |
ff4fa993 YR |
2289 | if (indep_p) |
2290 | { | |
2291 | unsigned i; | |
2292 | bitmap_iterator bi; | |
2293 | EXECUTE_IF_SET_IN_BITMAP (refs_to_check, 0, i, bi) | |
2294 | { | |
2295 | im_mem_ref *aref = memory_accesses.refs_list[i]; | |
2296 | if (!refs_independent_p (ref, aref)) | |
2297 | { | |
2298 | indep_p = false; | |
2299 | break; | |
2300 | } | |
2301 | } | |
2302 | } | |
c00217fc RB |
2303 | } |
2304 | ||
72425608 ZD |
2305 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2306 | fprintf (dump_file, "Querying dependencies of ref %u in loop %d: %s\n", | |
c00217fc | 2307 | ref->id, loop->num, indep_p ? "independent" : "dependent"); |
72425608 | 2308 | |
c00217fc RB |
2309 | /* Record the computed result in the cache. */ |
2310 | if (indep_p) | |
2311 | { | |
374001cb | 2312 | if (bitmap_set_bit (&ref->indep_loop, LOOP_DEP_BIT (loop->num, stored_p)) |
c00217fc RB |
2313 | && stored_p) |
2314 | { | |
2315 | /* If it's independend against all refs then it's independent | |
2316 | against stores, too. */ | |
374001cb | 2317 | bitmap_set_bit (&ref->indep_loop, LOOP_DEP_BIT (loop->num, false)); |
c00217fc RB |
2318 | } |
2319 | } | |
2320 | else | |
2321 | { | |
2322 | record_dep_loop (loop, ref, stored_p); | |
2323 | if (!stored_p) | |
2324 | { | |
2325 | /* If it's dependent against stores it's dependent against | |
2326 | all refs, too. */ | |
2327 | record_dep_loop (loop, ref, true); | |
2328 | } | |
2329 | } | |
72425608 | 2330 | |
c00217fc RB |
2331 | return indep_p; |
2332 | } | |
2333 | ||
2334 | /* Returns true if REF is independent on all other memory references in | |
bcfaa720 | 2335 | LOOP. */ |
c00217fc RB |
2336 | |
2337 | static bool | |
99b1c316 | 2338 | ref_indep_loop_p (class loop *loop, im_mem_ref *ref) |
c00217fc RB |
2339 | { |
2340 | gcc_checking_assert (MEM_ANALYZABLE (ref)); | |
2341 | ||
bcfaa720 | 2342 | return ref_indep_loop_p_1 (loop, ref, false); |
01fd257a ZD |
2343 | } |
2344 | ||
72425608 | 2345 | /* Returns true if we can perform store motion of REF from LOOP. */ |
01fd257a | 2346 | |
72425608 | 2347 | static bool |
99b1c316 | 2348 | can_sm_ref_p (class loop *loop, im_mem_ref *ref) |
01fd257a | 2349 | { |
58adb739 RG |
2350 | tree base; |
2351 | ||
546d314c RG |
2352 | /* Can't hoist unanalyzable refs. */ |
2353 | if (!MEM_ANALYZABLE (ref)) | |
2354 | return false; | |
2355 | ||
72425608 | 2356 | /* It should be movable. */ |
bdb01696 RB |
2357 | if (!is_gimple_reg_type (TREE_TYPE (ref->mem.ref)) |
2358 | || TREE_THIS_VOLATILE (ref->mem.ref) | |
2359 | || !for_each_index (&ref->mem.ref, may_move_till, loop)) | |
72425608 | 2360 | return false; |
ed9c043b | 2361 | |
9939e416 | 2362 | /* If it can throw fail, we do not properly update EH info. */ |
bdb01696 | 2363 | if (tree_could_throw_p (ref->mem.ref)) |
9939e416 RG |
2364 | return false; |
2365 | ||
58adb739 RG |
2366 | /* If it can trap, it must be always executed in LOOP. |
2367 | Readonly memory locations may trap when storing to them, but | |
2368 | tree_could_trap_p is a predicate for rvalues, so check that | |
2369 | explicitly. */ | |
bdb01696 RB |
2370 | base = get_base_address (ref->mem.ref); |
2371 | if ((tree_could_trap_p (ref->mem.ref) | |
58adb739 RG |
2372 | || (DECL_P (base) && TREE_READONLY (base))) |
2373 | && !ref_always_accessed_p (loop, ref, true)) | |
72425608 | 2374 | return false; |
ed9c043b | 2375 | |
72425608 ZD |
2376 | /* And it must be independent on all other memory references |
2377 | in LOOP. */ | |
bcfaa720 | 2378 | if (!ref_indep_loop_p (loop, ref)) |
72425608 | 2379 | return false; |
ed9c043b | 2380 | |
72425608 | 2381 | return true; |
ed9c043b ZD |
2382 | } |
2383 | ||
72425608 ZD |
2384 | /* Marks the references in LOOP for that store motion should be performed |
2385 | in REFS_TO_SM. SM_EXECUTED is the set of references for that store | |
2386 | motion was performed in one of the outer loops. */ | |
ed9c043b ZD |
2387 | |
2388 | static void | |
99b1c316 | 2389 | find_refs_for_sm (class loop *loop, bitmap sm_executed, bitmap refs_to_sm) |
01fd257a | 2390 | { |
374001cb | 2391 | bitmap refs = &memory_accesses.all_refs_stored_in_loop[loop->num]; |
72425608 ZD |
2392 | unsigned i; |
2393 | bitmap_iterator bi; | |
61baec41 | 2394 | im_mem_ref *ref; |
72425608 ZD |
2395 | |
2396 | EXECUTE_IF_AND_COMPL_IN_BITMAP (refs, sm_executed, 0, i, bi) | |
2397 | { | |
9771b263 | 2398 | ref = memory_accesses.refs_list[i]; |
72425608 ZD |
2399 | if (can_sm_ref_p (loop, ref)) |
2400 | bitmap_set_bit (refs_to_sm, i); | |
2401 | } | |
ed9c043b | 2402 | } |
01fd257a | 2403 | |
72425608 ZD |
2404 | /* Checks whether LOOP (with exits stored in EXITS array) is suitable |
2405 | for a store motion optimization (i.e. whether we can insert statement | |
2406 | on its exits). */ | |
ed9c043b | 2407 | |
72425608 | 2408 | static bool |
99b1c316 | 2409 | loop_suitable_for_sm (class loop *loop ATTRIBUTE_UNUSED, |
9771b263 | 2410 | vec<edge> exits) |
ed9c043b | 2411 | { |
72425608 ZD |
2412 | unsigned i; |
2413 | edge ex; | |
01fd257a | 2414 | |
9771b263 | 2415 | FOR_EACH_VEC_ELT (exits, i, ex) |
6391db68 | 2416 | if (ex->flags & (EDGE_ABNORMAL | EDGE_EH)) |
72425608 ZD |
2417 | return false; |
2418 | ||
2419 | return true; | |
01fd257a ZD |
2420 | } |
2421 | ||
a7e5372d | 2422 | /* Try to perform store motion for all memory references modified inside |
72425608 ZD |
2423 | LOOP. SM_EXECUTED is the bitmap of the memory references for that |
2424 | store motion was executed in one of the outer loops. */ | |
a7e5372d ZD |
2425 | |
2426 | static void | |
99b1c316 | 2427 | store_motion_loop (class loop *loop, bitmap sm_executed) |
a7e5372d | 2428 | { |
9771b263 | 2429 | vec<edge> exits = get_loop_exit_edges (loop); |
99b1c316 | 2430 | class loop *subloop; |
cad1735b | 2431 | bitmap sm_in_loop = BITMAP_ALLOC (&lim_bitmap_obstack); |
a7e5372d | 2432 | |
72425608 | 2433 | if (loop_suitable_for_sm (loop, exits)) |
a7e5372d | 2434 | { |
72425608 ZD |
2435 | find_refs_for_sm (loop, sm_executed, sm_in_loop); |
2436 | hoist_memory_references (loop, sm_in_loop, exits); | |
a7e5372d | 2437 | } |
9771b263 | 2438 | exits.release (); |
72425608 ZD |
2439 | |
2440 | bitmap_ior_into (sm_executed, sm_in_loop); | |
2441 | for (subloop = loop->inner; subloop != NULL; subloop = subloop->next) | |
2442 | store_motion_loop (subloop, sm_executed); | |
2443 | bitmap_and_compl_into (sm_executed, sm_in_loop); | |
2444 | BITMAP_FREE (sm_in_loop); | |
a7e5372d ZD |
2445 | } |
2446 | ||
2447 | /* Try to perform store motion for all memory references modified inside | |
d73be268 | 2448 | loops. */ |
a7e5372d ZD |
2449 | |
2450 | static void | |
72425608 | 2451 | store_motion (void) |
a7e5372d | 2452 | { |
99b1c316 | 2453 | class loop *loop; |
cad1735b | 2454 | bitmap sm_executed = BITMAP_ALLOC (&lim_bitmap_obstack); |
d16464bb | 2455 | |
72425608 ZD |
2456 | for (loop = current_loops->tree_root->inner; loop != NULL; loop = loop->next) |
2457 | store_motion_loop (loop, sm_executed); | |
42fd6772 | 2458 | |
72425608 | 2459 | BITMAP_FREE (sm_executed); |
726a989a | 2460 | gsi_commit_edge_inserts (); |
a7e5372d ZD |
2461 | } |
2462 | ||
2463 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks of LOOP, i.e. | |
2464 | for each such basic block bb records the outermost loop for that execution | |
2465 | of its header implies execution of bb. CONTAINS_CALL is the bitmap of | |
2466 | blocks that contain a nonpure call. */ | |
2467 | ||
2468 | static void | |
99b1c316 | 2469 | fill_always_executed_in_1 (class loop *loop, sbitmap contains_call) |
a7e5372d ZD |
2470 | { |
2471 | basic_block bb = NULL, *bbs, last = NULL; | |
2472 | unsigned i; | |
2473 | edge e; | |
99b1c316 | 2474 | class loop *inn_loop = loop; |
a7e5372d | 2475 | |
8a519095 | 2476 | if (ALWAYS_EXECUTED_IN (loop->header) == NULL) |
a7e5372d ZD |
2477 | { |
2478 | bbs = get_loop_body_in_dom_order (loop); | |
2479 | ||
2480 | for (i = 0; i < loop->num_nodes; i++) | |
2481 | { | |
628f6a4e | 2482 | edge_iterator ei; |
a7e5372d ZD |
2483 | bb = bbs[i]; |
2484 | ||
2485 | if (dominated_by_p (CDI_DOMINATORS, loop->latch, bb)) | |
2486 | last = bb; | |
2487 | ||
d7c028c0 | 2488 | if (bitmap_bit_p (contains_call, bb->index)) |
a7e5372d ZD |
2489 | break; |
2490 | ||
628f6a4e | 2491 | FOR_EACH_EDGE (e, ei, bb->succs) |
964ef24c RB |
2492 | { |
2493 | /* If there is an exit from this BB. */ | |
2494 | if (!flow_bb_inside_loop_p (loop, e->dest)) | |
2495 | break; | |
2496 | /* Or we enter a possibly non-finite loop. */ | |
2497 | if (flow_loop_nested_p (bb->loop_father, | |
2498 | e->dest->loop_father) | |
2499 | && ! finite_loop_p (e->dest->loop_father)) | |
2500 | break; | |
2501 | } | |
a7e5372d ZD |
2502 | if (e) |
2503 | break; | |
2504 | ||
2505 | /* A loop might be infinite (TODO use simple loop analysis | |
2506 | to disprove this if possible). */ | |
2507 | if (bb->flags & BB_IRREDUCIBLE_LOOP) | |
2508 | break; | |
2509 | ||
2510 | if (!flow_bb_inside_loop_p (inn_loop, bb)) | |
2511 | break; | |
2512 | ||
2513 | if (bb->loop_father->header == bb) | |
2514 | { | |
2515 | if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb)) | |
2516 | break; | |
2517 | ||
2518 | /* In a loop that is always entered we may proceed anyway. | |
2519 | But record that we entered it and stop once we leave it. */ | |
2520 | inn_loop = bb->loop_father; | |
2521 | } | |
2522 | } | |
2523 | ||
2524 | while (1) | |
2525 | { | |
8a519095 | 2526 | SET_ALWAYS_EXECUTED_IN (last, loop); |
a7e5372d ZD |
2527 | if (last == loop->header) |
2528 | break; | |
2529 | last = get_immediate_dominator (CDI_DOMINATORS, last); | |
2530 | } | |
2531 | ||
2532 | free (bbs); | |
2533 | } | |
2534 | ||
2535 | for (loop = loop->inner; loop; loop = loop->next) | |
374001cb | 2536 | fill_always_executed_in_1 (loop, contains_call); |
a7e5372d ZD |
2537 | } |
2538 | ||
374001cb RB |
2539 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks, i.e. |
2540 | for each such basic block bb records the outermost loop for that execution | |
2541 | of its header implies execution of bb. */ | |
a7e5372d ZD |
2542 | |
2543 | static void | |
374001cb | 2544 | fill_always_executed_in (void) |
a7e5372d | 2545 | { |
a7e5372d | 2546 | basic_block bb; |
99b1c316 | 2547 | class loop *loop; |
3f9b14ff | 2548 | |
7ba9e72d | 2549 | auto_sbitmap contains_call (last_basic_block_for_fn (cfun)); |
f61e445a | 2550 | bitmap_clear (contains_call); |
11cd3bed | 2551 | FOR_EACH_BB_FN (bb, cfun) |
a7e5372d | 2552 | { |
374001cb RB |
2553 | gimple_stmt_iterator gsi; |
2554 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
a7e5372d | 2555 | { |
374001cb | 2556 | if (nonpure_call_p (gsi_stmt (gsi))) |
a7e5372d ZD |
2557 | break; |
2558 | } | |
2559 | ||
374001cb | 2560 | if (!gsi_end_p (gsi)) |
d7c028c0 | 2561 | bitmap_set_bit (contains_call, bb->index); |
a7e5372d ZD |
2562 | } |
2563 | ||
d73be268 | 2564 | for (loop = current_loops->tree_root->inner; loop; loop = loop->next) |
374001cb | 2565 | fill_always_executed_in_1 (loop, contains_call); |
374001cb RB |
2566 | } |
2567 | ||
2568 | ||
2569 | /* Compute the global information needed by the loop invariant motion pass. */ | |
726a989a | 2570 | |
374001cb RB |
2571 | static void |
2572 | tree_ssa_lim_initialize (void) | |
2573 | { | |
99b1c316 | 2574 | class loop *loop; |
374001cb RB |
2575 | unsigned i; |
2576 | ||
2577 | bitmap_obstack_initialize (&lim_bitmap_obstack); | |
32500433 | 2578 | gcc_obstack_init (&mem_ref_obstack); |
355fe088 | 2579 | lim_aux_data_map = new hash_map<gimple *, lim_aux_data *>; |
19c0d7df AH |
2580 | |
2581 | if (flag_tm) | |
2582 | compute_transaction_bits (); | |
039496da AH |
2583 | |
2584 | alloc_aux_for_edges (0); | |
374001cb | 2585 | |
c203e8a7 | 2586 | memory_accesses.refs = new hash_table<mem_ref_hasher> (100); |
374001cb RB |
2587 | memory_accesses.refs_list.create (100); |
2588 | /* Allocate a special, unanalyzable mem-ref with ID zero. */ | |
2589 | memory_accesses.refs_list.quick_push | |
1c852d1d | 2590 | (mem_ref_alloc (NULL, 0, UNANALYZABLE_MEM_ID)); |
374001cb | 2591 | |
0fc822d0 RB |
2592 | memory_accesses.refs_in_loop.create (number_of_loops (cfun)); |
2593 | memory_accesses.refs_in_loop.quick_grow (number_of_loops (cfun)); | |
2594 | memory_accesses.refs_stored_in_loop.create (number_of_loops (cfun)); | |
2595 | memory_accesses.refs_stored_in_loop.quick_grow (number_of_loops (cfun)); | |
2596 | memory_accesses.all_refs_stored_in_loop.create (number_of_loops (cfun)); | |
2597 | memory_accesses.all_refs_stored_in_loop.quick_grow (number_of_loops (cfun)); | |
374001cb | 2598 | |
0fc822d0 | 2599 | for (i = 0; i < number_of_loops (cfun); i++) |
374001cb RB |
2600 | { |
2601 | bitmap_initialize (&memory_accesses.refs_in_loop[i], | |
2602 | &lim_bitmap_obstack); | |
2603 | bitmap_initialize (&memory_accesses.refs_stored_in_loop[i], | |
2604 | &lim_bitmap_obstack); | |
2605 | bitmap_initialize (&memory_accesses.all_refs_stored_in_loop[i], | |
2606 | &lim_bitmap_obstack); | |
2607 | } | |
2608 | ||
2609 | memory_accesses.ttae_cache = NULL; | |
32500433 RB |
2610 | |
2611 | /* Initialize bb_loop_postorder with a mapping from loop->num to | |
2612 | its postorder index. */ | |
2613 | i = 0; | |
2614 | bb_loop_postorder = XNEWVEC (unsigned, number_of_loops (cfun)); | |
2615 | FOR_EACH_LOOP (loop, LI_FROM_INNERMOST) | |
2616 | bb_loop_postorder[loop->num] = i++; | |
a7e5372d ZD |
2617 | } |
2618 | ||
2619 | /* Cleans up after the invariant motion pass. */ | |
2620 | ||
2621 | static void | |
2622 | tree_ssa_lim_finalize (void) | |
2623 | { | |
2624 | basic_block bb; | |
72425608 | 2625 | unsigned i; |
61baec41 | 2626 | im_mem_ref *ref; |
a7e5372d | 2627 | |
039496da AH |
2628 | free_aux_for_edges (); |
2629 | ||
11cd3bed | 2630 | FOR_EACH_BB_FN (bb, cfun) |
8a519095 | 2631 | SET_ALWAYS_EXECUTED_IN (bb, NULL); |
72425608 | 2632 | |
3f9b14ff | 2633 | bitmap_obstack_release (&lim_bitmap_obstack); |
b787e7a2 | 2634 | delete lim_aux_data_map; |
726a989a | 2635 | |
c203e8a7 TS |
2636 | delete memory_accesses.refs; |
2637 | memory_accesses.refs = NULL; | |
72425608 | 2638 | |
9771b263 | 2639 | FOR_EACH_VEC_ELT (memory_accesses.refs_list, i, ref) |
f5843d08 | 2640 | memref_free (ref); |
9771b263 | 2641 | memory_accesses.refs_list.release (); |
32500433 | 2642 | obstack_free (&mem_ref_obstack, NULL); |
f5843d08 | 2643 | |
9771b263 | 2644 | memory_accesses.refs_in_loop.release (); |
c00217fc | 2645 | memory_accesses.refs_stored_in_loop.release (); |
9771b263 | 2646 | memory_accesses.all_refs_stored_in_loop.release (); |
72425608 ZD |
2647 | |
2648 | if (memory_accesses.ttae_cache) | |
b6db991c | 2649 | free_affine_expand_cache (&memory_accesses.ttae_cache); |
32500433 RB |
2650 | |
2651 | free (bb_loop_postorder); | |
a7e5372d ZD |
2652 | } |
2653 | ||
d73be268 | 2654 | /* Moves invariants from loops. Only "expensive" invariants are moved out -- |
a7e5372d ZD |
2655 | i.e. those that are likely to be win regardless of the register pressure. */ |
2656 | ||
9c37629f | 2657 | static unsigned int |
d73be268 | 2658 | tree_ssa_lim (void) |
a7e5372d | 2659 | { |
e3bdfed6 RG |
2660 | unsigned int todo; |
2661 | ||
d73be268 | 2662 | tree_ssa_lim_initialize (); |
a7e5372d | 2663 | |
72425608 ZD |
2664 | /* Gathers information about memory accesses in the loops. */ |
2665 | analyze_memory_references (); | |
2666 | ||
374001cb RB |
2667 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks. */ |
2668 | fill_always_executed_in (); | |
2669 | ||
a7e5372d ZD |
2670 | /* For each statement determine the outermost loop in that it is |
2671 | invariant and cost for computing the invariant. */ | |
4d9192b5 TS |
2672 | invariantness_dom_walker (CDI_DOMINATORS) |
2673 | .walk (cfun->cfg->x_entry_block_ptr); | |
a7e5372d | 2674 | |
72425608 ZD |
2675 | /* Execute store motion. Force the necessary invariants to be moved |
2676 | out of the loops as well. */ | |
2677 | store_motion (); | |
a7e5372d ZD |
2678 | |
2679 | /* Move the expressions that are expensive enough. */ | |
e3bdfed6 | 2680 | todo = move_computations (); |
a7e5372d ZD |
2681 | |
2682 | tree_ssa_lim_finalize (); | |
e3bdfed6 RG |
2683 | |
2684 | return todo; | |
a7e5372d | 2685 | } |
71343877 AM |
2686 | |
2687 | /* Loop invariant motion pass. */ | |
2688 | ||
71343877 AM |
2689 | namespace { |
2690 | ||
2691 | const pass_data pass_data_lim = | |
2692 | { | |
2693 | GIMPLE_PASS, /* type */ | |
2694 | "lim", /* name */ | |
2695 | OPTGROUP_LOOP, /* optinfo_flags */ | |
71343877 AM |
2696 | TV_LIM, /* tv_id */ |
2697 | PROP_cfg, /* properties_required */ | |
2698 | 0, /* properties_provided */ | |
2699 | 0, /* properties_destroyed */ | |
2700 | 0, /* todo_flags_start */ | |
2701 | 0, /* todo_flags_finish */ | |
2702 | }; | |
2703 | ||
2704 | class pass_lim : public gimple_opt_pass | |
2705 | { | |
2706 | public: | |
2707 | pass_lim (gcc::context *ctxt) | |
2708 | : gimple_opt_pass (pass_data_lim, ctxt) | |
2709 | {} | |
2710 | ||
2711 | /* opt_pass methods: */ | |
2712 | opt_pass * clone () { return new pass_lim (m_ctxt); } | |
1a3d085c | 2713 | virtual bool gate (function *) { return flag_tree_loop_im != 0; } |
be55bfe6 | 2714 | virtual unsigned int execute (function *); |
71343877 AM |
2715 | |
2716 | }; // class pass_lim | |
2717 | ||
be55bfe6 TS |
2718 | unsigned int |
2719 | pass_lim::execute (function *fun) | |
2720 | { | |
9c37629f TV |
2721 | bool in_loop_pipeline = scev_initialized_p (); |
2722 | if (!in_loop_pipeline) | |
2723 | loop_optimizer_init (LOOPS_NORMAL | LOOPS_HAVE_RECORDED_EXITS); | |
2724 | ||
be55bfe6 TS |
2725 | if (number_of_loops (fun) <= 1) |
2726 | return 0; | |
9c37629f | 2727 | unsigned int todo = tree_ssa_lim (); |
be55bfe6 | 2728 | |
9c37629f TV |
2729 | if (!in_loop_pipeline) |
2730 | loop_optimizer_finalize (); | |
144a822f RB |
2731 | else |
2732 | scev_reset (); | |
9c37629f | 2733 | return todo; |
be55bfe6 TS |
2734 | } |
2735 | ||
71343877 AM |
2736 | } // anon namespace |
2737 | ||
2738 | gimple_opt_pass * | |
2739 | make_pass_lim (gcc::context *ctxt) | |
2740 | { | |
2741 | return new pass_lim (ctxt); | |
2742 | } | |
2743 | ||
2744 |