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7d23383d | 1 | /* Loop invariant motion. |
711789cc | 2 | Copyright (C) 2003-2013 Free Software Foundation, Inc. |
48e1416a | 3 | |
7d23383d | 4 | This file is part of GCC. |
48e1416a | 5 | |
7d23383d | 6 | GCC is free software; you can redistribute it and/or modify it |
7 | under the terms of the GNU General Public License as published by the | |
8c4c00c1 | 8 | Free Software Foundation; either version 3, or (at your option) any |
7d23383d | 9 | later version. |
48e1416a | 10 | |
7d23383d | 11 | GCC is distributed in the hope that it will be useful, but WITHOUT |
12 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
48e1416a | 15 | |
7d23383d | 16 | You should have received a copy of the GNU General Public License |
8c4c00c1 | 17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
7d23383d | 19 | |
20 | #include "config.h" | |
21 | #include "system.h" | |
22 | #include "coretypes.h" | |
23 | #include "tm.h" | |
24 | #include "tree.h" | |
7d23383d | 25 | #include "tm_p.h" |
7d23383d | 26 | #include "basic-block.h" |
8e3cb73b | 27 | #include "gimple-pretty-print.h" |
e795d6e1 | 28 | #include "gimple.h" |
a8783bee | 29 | #include "gimplify.h" |
dcf1a1ec | 30 | #include "gimple-iterator.h" |
e795d6e1 | 31 | #include "gimplify-me.h" |
073c1fd5 | 32 | #include "gimple-ssa.h" |
33 | #include "tree-cfg.h" | |
34 | #include "tree-phinodes.h" | |
35 | #include "ssa-iterators.h" | |
9ed99284 | 36 | #include "stringpool.h" |
073c1fd5 | 37 | #include "tree-ssanames.h" |
05d9c18a | 38 | #include "tree-ssa-loop-manip.h" |
073c1fd5 | 39 | #include "tree-ssa-loop.h" |
40 | #include "tree-into-ssa.h" | |
7d23383d | 41 | #include "cfgloop.h" |
42 | #include "domwalk.h" | |
43 | #include "params.h" | |
44 | #include "tree-pass.h" | |
45 | #include "flags.h" | |
3e871d4d | 46 | #include "hash-table.h" |
063a8bce | 47 | #include "tree-affine.h" |
48 | #include "pointer-set.h" | |
a973ed42 | 49 | #include "tree-ssa-propagate.h" |
e797f49f | 50 | #include "trans-mem.h" |
7d23383d | 51 | |
ca53beb1 | 52 | /* TODO: Support for predicated code motion. I.e. |
53 | ||
54 | while (1) | |
55 | { | |
56 | if (cond) | |
57 | { | |
58 | a = inv; | |
59 | something; | |
60 | } | |
61 | } | |
62 | ||
61025ec0 | 63 | Where COND and INV are invariants, but evaluating INV may trap or be |
ca53beb1 | 64 | invalid from some other reason if !COND. This may be transformed to |
65 | ||
66 | if (cond) | |
67 | a = inv; | |
68 | while (1) | |
69 | { | |
70 | if (cond) | |
71 | something; | |
72 | } */ | |
73 | ||
7d23383d | 74 | /* The auxiliary data kept for each statement. */ |
75 | ||
76 | struct lim_aux_data | |
77 | { | |
78 | struct loop *max_loop; /* The outermost loop in that the statement | |
79 | is invariant. */ | |
80 | ||
81 | struct loop *tgt_loop; /* The loop out of that we want to move the | |
82 | invariant. */ | |
83 | ||
84 | struct loop *always_executed_in; | |
85 | /* The outermost loop for that we are sure | |
86 | the statement is executed if the loop | |
87 | is entered. */ | |
88 | ||
7d23383d | 89 | unsigned cost; /* Cost of the computation performed by the |
90 | statement. */ | |
91 | ||
a2c22c0d | 92 | vec<gimple> depends; /* Vector of statements that must be also |
93 | hoisted out of the loop when this statement | |
94 | is hoisted; i.e. those that define the | |
95 | operands of the statement and are inside of | |
96 | the MAX_LOOP loop. */ | |
7d23383d | 97 | }; |
98 | ||
75a70cf9 | 99 | /* Maps statements to their lim_aux_data. */ |
100 | ||
101 | static struct pointer_map_t *lim_aux_data_map; | |
7d23383d | 102 | |
063a8bce | 103 | /* Description of a memory reference location. */ |
7d23383d | 104 | |
063a8bce | 105 | typedef struct mem_ref_loc |
7d23383d | 106 | { |
107 | tree *ref; /* The reference itself. */ | |
75a70cf9 | 108 | gimple stmt; /* The statement in that it occurs. */ |
063a8bce | 109 | } *mem_ref_loc_p; |
110 | ||
063a8bce | 111 | |
063a8bce | 112 | /* Description of a memory reference. */ |
113 | ||
114 | typedef struct mem_ref | |
55a03692 | 115 | { |
063a8bce | 116 | unsigned id; /* ID assigned to the memory reference |
117 | (its index in memory_accesses.refs_list) */ | |
55a03692 | 118 | hashval_t hash; /* Its hash value. */ |
09f4cf62 | 119 | |
120 | /* The memory access itself and associated caching of alias-oracle | |
121 | query meta-data. */ | |
122 | ao_ref mem; | |
123 | ||
feba4360 | 124 | bitmap_head stored; /* The set of loops in that this memory location |
063a8bce | 125 | is stored to. */ |
5c8a8be3 | 126 | vec<vec<mem_ref_loc> > accesses_in_loop; |
063a8bce | 127 | /* The locations of the accesses. Vector |
128 | indexed by the loop number. */ | |
063a8bce | 129 | |
130 | /* The following sets are computed on demand. We keep both set and | |
131 | its complement, so that we know whether the information was | |
132 | already computed or not. */ | |
feba4360 | 133 | bitmap_head indep_loop; /* The set of loops in that the memory |
063a8bce | 134 | reference is independent, meaning: |
135 | If it is stored in the loop, this store | |
136 | is independent on all other loads and | |
137 | stores. | |
138 | If it is only loaded, then it is independent | |
139 | on all stores in the loop. */ | |
feba4360 | 140 | bitmap_head dep_loop; /* The complement of INDEP_LOOP. */ |
063a8bce | 141 | } *mem_ref_p; |
142 | ||
8f9829e8 | 143 | /* We use two bits per loop in the ref->{in,}dep_loop bitmaps, the first |
144 | to record (in)dependence against stores in the loop and its subloops, the | |
145 | second to record (in)dependence against all references in the loop | |
146 | and its subloops. */ | |
147 | #define LOOP_DEP_BIT(loopnum, storedp) (2 * (loopnum) + (storedp ? 1 : 0)) | |
063a8bce | 148 | |
3e871d4d | 149 | /* Mem_ref hashtable helpers. */ |
150 | ||
151 | struct mem_ref_hasher : typed_noop_remove <mem_ref> | |
152 | { | |
153 | typedef mem_ref value_type; | |
154 | typedef tree_node compare_type; | |
155 | static inline hashval_t hash (const value_type *); | |
156 | static inline bool equal (const value_type *, const compare_type *); | |
157 | }; | |
158 | ||
159 | /* A hash function for struct mem_ref object OBJ. */ | |
160 | ||
161 | inline hashval_t | |
162 | mem_ref_hasher::hash (const value_type *mem) | |
163 | { | |
164 | return mem->hash; | |
165 | } | |
166 | ||
167 | /* An equality function for struct mem_ref object MEM1 with | |
168 | memory reference OBJ2. */ | |
169 | ||
170 | inline bool | |
171 | mem_ref_hasher::equal (const value_type *mem1, const compare_type *obj2) | |
172 | { | |
173 | return operand_equal_p (mem1->mem.ref, (const_tree) obj2, 0); | |
174 | } | |
063a8bce | 175 | |
063a8bce | 176 | |
177 | /* Description of memory accesses in loops. */ | |
178 | ||
179 | static struct | |
180 | { | |
181 | /* The hash table of memory references accessed in loops. */ | |
3e871d4d | 182 | hash_table <mem_ref_hasher> refs; |
063a8bce | 183 | |
184 | /* The list of memory references. */ | |
f1f41a6c | 185 | vec<mem_ref_p> refs_list; |
063a8bce | 186 | |
187 | /* The set of memory references accessed in each loop. */ | |
feba4360 | 188 | vec<bitmap_head> refs_in_loop; |
063a8bce | 189 | |
8f9829e8 | 190 | /* The set of memory references stored in each loop. */ |
feba4360 | 191 | vec<bitmap_head> refs_stored_in_loop; |
8f9829e8 | 192 | |
8f9829e8 | 193 | /* The set of memory references stored in each loop, including subloops . */ |
feba4360 | 194 | vec<bitmap_head> all_refs_stored_in_loop; |
063a8bce | 195 | |
196 | /* Cache for expanding memory addresses. */ | |
197 | struct pointer_map_t *ttae_cache; | |
198 | } memory_accesses; | |
199 | ||
4fb07d00 | 200 | /* Obstack for the bitmaps in the above data structures. */ |
201 | static bitmap_obstack lim_bitmap_obstack; | |
202 | ||
063a8bce | 203 | static bool ref_indep_loop_p (struct loop *, mem_ref_p); |
7d23383d | 204 | |
205 | /* Minimum cost of an expensive expression. */ | |
206 | #define LIM_EXPENSIVE ((unsigned) PARAM_VALUE (PARAM_LIM_EXPENSIVE)) | |
207 | ||
2fd20c29 | 208 | /* The outermost loop for which execution of the header guarantees that the |
7d23383d | 209 | block will be executed. */ |
210 | #define ALWAYS_EXECUTED_IN(BB) ((struct loop *) (BB)->aux) | |
2fd20c29 | 211 | #define SET_ALWAYS_EXECUTED_IN(BB, VAL) ((BB)->aux = (void *) (VAL)) |
7d23383d | 212 | |
04911505 | 213 | /* ID of the shared unanalyzable mem. */ |
214 | #define UNANALYZABLE_MEM_ID 0 | |
215 | ||
0766b2c0 | 216 | /* Whether the reference was analyzable. */ |
04911505 | 217 | #define MEM_ANALYZABLE(REF) ((REF)->id != UNANALYZABLE_MEM_ID) |
0766b2c0 | 218 | |
75a70cf9 | 219 | static struct lim_aux_data * |
220 | init_lim_data (gimple stmt) | |
221 | { | |
222 | void **p = pointer_map_insert (lim_aux_data_map, stmt); | |
223 | ||
224 | *p = XCNEW (struct lim_aux_data); | |
225 | return (struct lim_aux_data *) *p; | |
226 | } | |
227 | ||
228 | static struct lim_aux_data * | |
229 | get_lim_data (gimple stmt) | |
230 | { | |
231 | void **p = pointer_map_contains (lim_aux_data_map, stmt); | |
232 | if (!p) | |
233 | return NULL; | |
234 | ||
235 | return (struct lim_aux_data *) *p; | |
236 | } | |
237 | ||
238 | /* Releases the memory occupied by DATA. */ | |
239 | ||
240 | static void | |
241 | free_lim_aux_data (struct lim_aux_data *data) | |
242 | { | |
9af5ce0c | 243 | data->depends.release (); |
75a70cf9 | 244 | free (data); |
245 | } | |
246 | ||
247 | static void | |
248 | clear_lim_data (gimple stmt) | |
249 | { | |
250 | void **p = pointer_map_contains (lim_aux_data_map, stmt); | |
251 | if (!p) | |
252 | return; | |
253 | ||
254 | free_lim_aux_data ((struct lim_aux_data *) *p); | |
255 | *p = NULL; | |
256 | } | |
257 | ||
48e1416a | 258 | |
f86b328b | 259 | /* The possibilities of statement movement. */ |
260 | enum move_pos | |
261 | { | |
262 | MOVE_IMPOSSIBLE, /* No movement -- side effect expression. */ | |
263 | MOVE_PRESERVE_EXECUTION, /* Must not cause the non-executed statement | |
264 | become executed -- memory accesses, ... */ | |
265 | MOVE_POSSIBLE /* Unlimited movement. */ | |
266 | }; | |
a59824bb | 267 | |
7d23383d | 268 | |
269 | /* If it is possible to hoist the statement STMT unconditionally, | |
270 | returns MOVE_POSSIBLE. | |
271 | If it is possible to hoist the statement STMT, but we must avoid making | |
272 | it executed if it would not be executed in the original program (e.g. | |
273 | because it may trap), return MOVE_PRESERVE_EXECUTION. | |
274 | Otherwise return MOVE_IMPOSSIBLE. */ | |
275 | ||
07c03fb0 | 276 | enum move_pos |
75a70cf9 | 277 | movement_possibility (gimple stmt) |
7d23383d | 278 | { |
75a70cf9 | 279 | tree lhs; |
280 | enum move_pos ret = MOVE_POSSIBLE; | |
7d23383d | 281 | |
282 | if (flag_unswitch_loops | |
75a70cf9 | 283 | && gimple_code (stmt) == GIMPLE_COND) |
7d23383d | 284 | { |
285 | /* If we perform unswitching, force the operands of the invariant | |
286 | condition to be moved out of the loop. */ | |
7d23383d | 287 | return MOVE_POSSIBLE; |
288 | } | |
289 | ||
9bf0a3f9 | 290 | if (gimple_code (stmt) == GIMPLE_PHI |
291 | && gimple_phi_num_args (stmt) <= 2 | |
7c782c9b | 292 | && !virtual_operand_p (gimple_phi_result (stmt)) |
9bf0a3f9 | 293 | && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (gimple_phi_result (stmt))) |
294 | return MOVE_POSSIBLE; | |
295 | ||
75a70cf9 | 296 | if (gimple_get_lhs (stmt) == NULL_TREE) |
7d23383d | 297 | return MOVE_IMPOSSIBLE; |
298 | ||
dd277d48 | 299 | if (gimple_vdef (stmt)) |
063a8bce | 300 | return MOVE_IMPOSSIBLE; |
301 | ||
75a70cf9 | 302 | if (stmt_ends_bb_p (stmt) |
303 | || gimple_has_volatile_ops (stmt) | |
304 | || gimple_has_side_effects (stmt) | |
305 | || stmt_could_throw_p (stmt)) | |
7d23383d | 306 | return MOVE_IMPOSSIBLE; |
307 | ||
75a70cf9 | 308 | if (is_gimple_call (stmt)) |
ca53beb1 | 309 | { |
310 | /* While pure or const call is guaranteed to have no side effects, we | |
311 | cannot move it arbitrarily. Consider code like | |
312 | ||
313 | char *s = something (); | |
314 | ||
315 | while (1) | |
316 | { | |
317 | if (s) | |
318 | t = strlen (s); | |
319 | else | |
320 | t = 0; | |
321 | } | |
322 | ||
323 | Here the strlen call cannot be moved out of the loop, even though | |
324 | s is invariant. In addition to possibly creating a call with | |
325 | invalid arguments, moving out a function call that is not executed | |
326 | may cause performance regressions in case the call is costly and | |
327 | not executed at all. */ | |
75a70cf9 | 328 | ret = MOVE_PRESERVE_EXECUTION; |
329 | lhs = gimple_call_lhs (stmt); | |
ca53beb1 | 330 | } |
75a70cf9 | 331 | else if (is_gimple_assign (stmt)) |
332 | lhs = gimple_assign_lhs (stmt); | |
333 | else | |
334 | return MOVE_IMPOSSIBLE; | |
335 | ||
336 | if (TREE_CODE (lhs) == SSA_NAME | |
337 | && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (lhs)) | |
338 | return MOVE_IMPOSSIBLE; | |
339 | ||
340 | if (TREE_CODE (lhs) != SSA_NAME | |
341 | || gimple_could_trap_p (stmt)) | |
342 | return MOVE_PRESERVE_EXECUTION; | |
343 | ||
de60f90c | 344 | /* Non local loads in a transaction cannot be hoisted out. Well, |
345 | unless the load happens on every path out of the loop, but we | |
346 | don't take this into account yet. */ | |
347 | if (flag_tm | |
348 | && gimple_in_transaction (stmt) | |
349 | && gimple_assign_single_p (stmt)) | |
350 | { | |
351 | tree rhs = gimple_assign_rhs1 (stmt); | |
352 | if (DECL_P (rhs) && is_global_var (rhs)) | |
353 | { | |
354 | if (dump_file) | |
355 | { | |
356 | fprintf (dump_file, "Cannot hoist conditional load of "); | |
357 | print_generic_expr (dump_file, rhs, TDF_SLIM); | |
358 | fprintf (dump_file, " because it is in a transaction.\n"); | |
359 | } | |
360 | return MOVE_IMPOSSIBLE; | |
361 | } | |
362 | } | |
363 | ||
75a70cf9 | 364 | return ret; |
7d23383d | 365 | } |
366 | ||
367 | /* Suppose that operand DEF is used inside the LOOP. Returns the outermost | |
91275768 | 368 | loop to that we could move the expression using DEF if it did not have |
7d23383d | 369 | other operands, i.e. the outermost loop enclosing LOOP in that the value |
370 | of DEF is invariant. */ | |
371 | ||
372 | static struct loop * | |
373 | outermost_invariant_loop (tree def, struct loop *loop) | |
374 | { | |
75a70cf9 | 375 | gimple def_stmt; |
7d23383d | 376 | basic_block def_bb; |
377 | struct loop *max_loop; | |
75a70cf9 | 378 | struct lim_aux_data *lim_data; |
7d23383d | 379 | |
75a70cf9 | 380 | if (!def) |
7d23383d | 381 | return superloop_at_depth (loop, 1); |
382 | ||
75a70cf9 | 383 | if (TREE_CODE (def) != SSA_NAME) |
384 | { | |
385 | gcc_assert (is_gimple_min_invariant (def)); | |
386 | return superloop_at_depth (loop, 1); | |
387 | } | |
388 | ||
7d23383d | 389 | def_stmt = SSA_NAME_DEF_STMT (def); |
75a70cf9 | 390 | def_bb = gimple_bb (def_stmt); |
7d23383d | 391 | if (!def_bb) |
392 | return superloop_at_depth (loop, 1); | |
393 | ||
394 | max_loop = find_common_loop (loop, def_bb->loop_father); | |
395 | ||
75a70cf9 | 396 | lim_data = get_lim_data (def_stmt); |
397 | if (lim_data != NULL && lim_data->max_loop != NULL) | |
7d23383d | 398 | max_loop = find_common_loop (max_loop, |
75a70cf9 | 399 | loop_outer (lim_data->max_loop)); |
7d23383d | 400 | if (max_loop == loop) |
401 | return NULL; | |
9e3536f4 | 402 | max_loop = superloop_at_depth (loop, loop_depth (max_loop) + 1); |
7d23383d | 403 | |
404 | return max_loop; | |
405 | } | |
406 | ||
7d23383d | 407 | /* DATA is a structure containing information associated with a statement |
408 | inside LOOP. DEF is one of the operands of this statement. | |
48e1416a | 409 | |
7d23383d | 410 | Find the outermost loop enclosing LOOP in that value of DEF is invariant |
411 | and record this in DATA->max_loop field. If DEF itself is defined inside | |
412 | this loop as well (i.e. we need to hoist it out of the loop if we want | |
413 | to hoist the statement represented by DATA), record the statement in that | |
414 | DEF is defined to the DATA->depends list. Additionally if ADD_COST is true, | |
415 | add the cost of the computation of DEF to the DATA->cost. | |
48e1416a | 416 | |
7d23383d | 417 | If DEF is not invariant in LOOP, return false. Otherwise return TRUE. */ |
418 | ||
419 | static bool | |
420 | add_dependency (tree def, struct lim_aux_data *data, struct loop *loop, | |
421 | bool add_cost) | |
422 | { | |
75a70cf9 | 423 | gimple def_stmt = SSA_NAME_DEF_STMT (def); |
424 | basic_block def_bb = gimple_bb (def_stmt); | |
7d23383d | 425 | struct loop *max_loop; |
75a70cf9 | 426 | struct lim_aux_data *def_data; |
7d23383d | 427 | |
428 | if (!def_bb) | |
429 | return true; | |
430 | ||
431 | max_loop = outermost_invariant_loop (def, loop); | |
432 | if (!max_loop) | |
433 | return false; | |
434 | ||
435 | if (flow_loop_nested_p (data->max_loop, max_loop)) | |
436 | data->max_loop = max_loop; | |
437 | ||
75a70cf9 | 438 | def_data = get_lim_data (def_stmt); |
439 | if (!def_data) | |
7d23383d | 440 | return true; |
441 | ||
442 | if (add_cost | |
443 | /* Only add the cost if the statement defining DEF is inside LOOP, | |
444 | i.e. if it is likely that by moving the invariants dependent | |
445 | on it, we will be able to avoid creating a new register for | |
446 | it (since it will be only used in these dependent invariants). */ | |
447 | && def_bb->loop_father == loop) | |
75a70cf9 | 448 | data->cost += def_data->cost; |
7d23383d | 449 | |
a2c22c0d | 450 | data->depends.safe_push (def_stmt); |
7d23383d | 451 | |
452 | return true; | |
453 | } | |
454 | ||
0766b2c0 | 455 | /* Returns an estimate for a cost of statement STMT. The values here |
456 | are just ad-hoc constants, similar to costs for inlining. */ | |
7d23383d | 457 | |
458 | static unsigned | |
75a70cf9 | 459 | stmt_cost (gimple stmt) |
7d23383d | 460 | { |
7d23383d | 461 | /* Always try to create possibilities for unswitching. */ |
9bf0a3f9 | 462 | if (gimple_code (stmt) == GIMPLE_COND |
463 | || gimple_code (stmt) == GIMPLE_PHI) | |
7d23383d | 464 | return LIM_EXPENSIVE; |
465 | ||
0766b2c0 | 466 | /* We should be hoisting calls if possible. */ |
75a70cf9 | 467 | if (is_gimple_call (stmt)) |
7d23383d | 468 | { |
0766b2c0 | 469 | tree fndecl; |
7d23383d | 470 | |
471 | /* Unless the call is a builtin_constant_p; this always folds to a | |
472 | constant, so moving it is useless. */ | |
75a70cf9 | 473 | fndecl = gimple_call_fndecl (stmt); |
474 | if (fndecl | |
475 | && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL | |
476 | && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_CONSTANT_P) | |
7d23383d | 477 | return 0; |
478 | ||
0766b2c0 | 479 | return LIM_EXPENSIVE; |
75a70cf9 | 480 | } |
481 | ||
0766b2c0 | 482 | /* Hoisting memory references out should almost surely be a win. */ |
483 | if (gimple_references_memory_p (stmt)) | |
484 | return LIM_EXPENSIVE; | |
485 | ||
75a70cf9 | 486 | if (gimple_code (stmt) != GIMPLE_ASSIGN) |
0766b2c0 | 487 | return 1; |
7d23383d | 488 | |
75a70cf9 | 489 | switch (gimple_assign_rhs_code (stmt)) |
490 | { | |
7d23383d | 491 | case MULT_EXPR: |
23da77dd | 492 | case WIDEN_MULT_EXPR: |
493 | case WIDEN_MULT_PLUS_EXPR: | |
494 | case WIDEN_MULT_MINUS_EXPR: | |
495 | case DOT_PROD_EXPR: | |
496 | case FMA_EXPR: | |
7d23383d | 497 | case TRUNC_DIV_EXPR: |
498 | case CEIL_DIV_EXPR: | |
499 | case FLOOR_DIV_EXPR: | |
500 | case ROUND_DIV_EXPR: | |
501 | case EXACT_DIV_EXPR: | |
502 | case CEIL_MOD_EXPR: | |
503 | case FLOOR_MOD_EXPR: | |
504 | case ROUND_MOD_EXPR: | |
505 | case TRUNC_MOD_EXPR: | |
fd544fc8 | 506 | case RDIV_EXPR: |
7d23383d | 507 | /* Division and multiplication are usually expensive. */ |
0766b2c0 | 508 | return LIM_EXPENSIVE; |
7d23383d | 509 | |
790963ba | 510 | case LSHIFT_EXPR: |
511 | case RSHIFT_EXPR: | |
23da77dd | 512 | case WIDEN_LSHIFT_EXPR: |
513 | case LROTATE_EXPR: | |
514 | case RROTATE_EXPR: | |
0766b2c0 | 515 | /* Shifts and rotates are usually expensive. */ |
516 | return LIM_EXPENSIVE; | |
517 | ||
518 | case CONSTRUCTOR: | |
519 | /* Make vector construction cost proportional to the number | |
520 | of elements. */ | |
521 | return CONSTRUCTOR_NELTS (gimple_assign_rhs1 (stmt)); | |
522 | ||
523 | case SSA_NAME: | |
524 | case PAREN_EXPR: | |
525 | /* Whether or not something is wrapped inside a PAREN_EXPR | |
526 | should not change move cost. Nor should an intermediate | |
527 | unpropagated SSA name copy. */ | |
528 | return 0; | |
790963ba | 529 | |
7d23383d | 530 | default: |
0766b2c0 | 531 | return 1; |
7d23383d | 532 | } |
7d23383d | 533 | } |
534 | ||
063a8bce | 535 | /* Finds the outermost loop between OUTER and LOOP in that the memory reference |
536 | REF is independent. If REF is not independent in LOOP, NULL is returned | |
537 | instead. */ | |
538 | ||
539 | static struct loop * | |
540 | outermost_indep_loop (struct loop *outer, struct loop *loop, mem_ref_p ref) | |
541 | { | |
542 | struct loop *aloop; | |
543 | ||
feba4360 | 544 | if (bitmap_bit_p (&ref->stored, loop->num)) |
063a8bce | 545 | return NULL; |
546 | ||
547 | for (aloop = outer; | |
548 | aloop != loop; | |
549 | aloop = superloop_at_depth (loop, loop_depth (aloop) + 1)) | |
feba4360 | 550 | if (!bitmap_bit_p (&ref->stored, aloop->num) |
063a8bce | 551 | && ref_indep_loop_p (aloop, ref)) |
552 | return aloop; | |
553 | ||
554 | if (ref_indep_loop_p (loop, ref)) | |
555 | return loop; | |
556 | else | |
557 | return NULL; | |
558 | } | |
559 | ||
560 | /* If there is a simple load or store to a memory reference in STMT, returns | |
f0b5f617 | 561 | the location of the memory reference, and sets IS_STORE according to whether |
063a8bce | 562 | it is a store or load. Otherwise, returns NULL. */ |
563 | ||
564 | static tree * | |
75a70cf9 | 565 | simple_mem_ref_in_stmt (gimple stmt, bool *is_store) |
063a8bce | 566 | { |
6d7105fe | 567 | tree *lhs, *rhs; |
063a8bce | 568 | |
6d7105fe | 569 | /* Recognize SSA_NAME = MEM and MEM = (SSA_NAME | invariant) patterns. */ |
570 | if (!gimple_assign_single_p (stmt)) | |
063a8bce | 571 | return NULL; |
572 | ||
75a70cf9 | 573 | lhs = gimple_assign_lhs_ptr (stmt); |
6d7105fe | 574 | rhs = gimple_assign_rhs1_ptr (stmt); |
063a8bce | 575 | |
6d7105fe | 576 | if (TREE_CODE (*lhs) == SSA_NAME && gimple_vuse (stmt)) |
063a8bce | 577 | { |
063a8bce | 578 | *is_store = false; |
6d7105fe | 579 | return rhs; |
063a8bce | 580 | } |
6d7105fe | 581 | else if (gimple_vdef (stmt) |
582 | && (TREE_CODE (*rhs) == SSA_NAME || is_gimple_min_invariant (*rhs))) | |
063a8bce | 583 | { |
584 | *is_store = true; | |
585 | return lhs; | |
586 | } | |
587 | else | |
588 | return NULL; | |
589 | } | |
590 | ||
591 | /* Returns the memory reference contained in STMT. */ | |
592 | ||
593 | static mem_ref_p | |
75a70cf9 | 594 | mem_ref_in_stmt (gimple stmt) |
063a8bce | 595 | { |
596 | bool store; | |
597 | tree *mem = simple_mem_ref_in_stmt (stmt, &store); | |
598 | hashval_t hash; | |
599 | mem_ref_p ref; | |
600 | ||
601 | if (!mem) | |
602 | return NULL; | |
603 | gcc_assert (!store); | |
604 | ||
605 | hash = iterative_hash_expr (*mem, 0); | |
3e871d4d | 606 | ref = memory_accesses.refs.find_with_hash (*mem, hash); |
063a8bce | 607 | |
608 | gcc_assert (ref != NULL); | |
609 | return ref; | |
610 | } | |
611 | ||
9bf0a3f9 | 612 | /* From a controlling predicate in DOM determine the arguments from |
613 | the PHI node PHI that are chosen if the predicate evaluates to | |
614 | true and false and store them to *TRUE_ARG_P and *FALSE_ARG_P if | |
615 | they are non-NULL. Returns true if the arguments can be determined, | |
616 | else return false. */ | |
617 | ||
618 | static bool | |
619 | extract_true_false_args_from_phi (basic_block dom, gimple phi, | |
620 | tree *true_arg_p, tree *false_arg_p) | |
621 | { | |
622 | basic_block bb = gimple_bb (phi); | |
623 | edge true_edge, false_edge, tem; | |
624 | tree arg0 = NULL_TREE, arg1 = NULL_TREE; | |
625 | ||
626 | /* We have to verify that one edge into the PHI node is dominated | |
627 | by the true edge of the predicate block and the other edge | |
628 | dominated by the false edge. This ensures that the PHI argument | |
629 | we are going to take is completely determined by the path we | |
b533d4c1 | 630 | take from the predicate block. |
631 | We can only use BB dominance checks below if the destination of | |
632 | the true/false edges are dominated by their edge, thus only | |
633 | have a single predecessor. */ | |
9bf0a3f9 | 634 | extract_true_false_edges_from_block (dom, &true_edge, &false_edge); |
635 | tem = EDGE_PRED (bb, 0); | |
636 | if (tem == true_edge | |
b533d4c1 | 637 | || (single_pred_p (true_edge->dest) |
638 | && (tem->src == true_edge->dest | |
639 | || dominated_by_p (CDI_DOMINATORS, | |
640 | tem->src, true_edge->dest)))) | |
9bf0a3f9 | 641 | arg0 = PHI_ARG_DEF (phi, tem->dest_idx); |
642 | else if (tem == false_edge | |
b533d4c1 | 643 | || (single_pred_p (false_edge->dest) |
644 | && (tem->src == false_edge->dest | |
645 | || dominated_by_p (CDI_DOMINATORS, | |
646 | tem->src, false_edge->dest)))) | |
9bf0a3f9 | 647 | arg1 = PHI_ARG_DEF (phi, tem->dest_idx); |
648 | else | |
649 | return false; | |
650 | tem = EDGE_PRED (bb, 1); | |
651 | if (tem == true_edge | |
b533d4c1 | 652 | || (single_pred_p (true_edge->dest) |
653 | && (tem->src == true_edge->dest | |
654 | || dominated_by_p (CDI_DOMINATORS, | |
655 | tem->src, true_edge->dest)))) | |
9bf0a3f9 | 656 | arg0 = PHI_ARG_DEF (phi, tem->dest_idx); |
657 | else if (tem == false_edge | |
b533d4c1 | 658 | || (single_pred_p (false_edge->dest) |
659 | && (tem->src == false_edge->dest | |
660 | || dominated_by_p (CDI_DOMINATORS, | |
661 | tem->src, false_edge->dest)))) | |
9bf0a3f9 | 662 | arg1 = PHI_ARG_DEF (phi, tem->dest_idx); |
663 | else | |
664 | return false; | |
665 | if (!arg0 || !arg1) | |
666 | return false; | |
667 | ||
668 | if (true_arg_p) | |
669 | *true_arg_p = arg0; | |
670 | if (false_arg_p) | |
671 | *false_arg_p = arg1; | |
672 | ||
673 | return true; | |
674 | } | |
675 | ||
7d23383d | 676 | /* Determine the outermost loop to that it is possible to hoist a statement |
677 | STMT and store it to LIM_DATA (STMT)->max_loop. To do this we determine | |
678 | the outermost loop in that the value computed by STMT is invariant. | |
679 | If MUST_PRESERVE_EXEC is true, additionally choose such a loop that | |
680 | we preserve the fact whether STMT is executed. It also fills other related | |
681 | information to LIM_DATA (STMT). | |
48e1416a | 682 | |
7d23383d | 683 | The function returns false if STMT cannot be hoisted outside of the loop it |
684 | is defined in, and true otherwise. */ | |
685 | ||
686 | static bool | |
75a70cf9 | 687 | determine_max_movement (gimple stmt, bool must_preserve_exec) |
7d23383d | 688 | { |
75a70cf9 | 689 | basic_block bb = gimple_bb (stmt); |
7d23383d | 690 | struct loop *loop = bb->loop_father; |
691 | struct loop *level; | |
75a70cf9 | 692 | struct lim_aux_data *lim_data = get_lim_data (stmt); |
43daa21e | 693 | tree val; |
694 | ssa_op_iter iter; | |
48e1416a | 695 | |
7d23383d | 696 | if (must_preserve_exec) |
697 | level = ALWAYS_EXECUTED_IN (bb); | |
698 | else | |
699 | level = superloop_at_depth (loop, 1); | |
700 | lim_data->max_loop = level; | |
701 | ||
9bf0a3f9 | 702 | if (gimple_code (stmt) == GIMPLE_PHI) |
703 | { | |
704 | use_operand_p use_p; | |
705 | unsigned min_cost = UINT_MAX; | |
706 | unsigned total_cost = 0; | |
707 | struct lim_aux_data *def_data; | |
708 | ||
709 | /* We will end up promoting dependencies to be unconditionally | |
710 | evaluated. For this reason the PHI cost (and thus the | |
711 | cost we remove from the loop by doing the invariant motion) | |
712 | is that of the cheapest PHI argument dependency chain. */ | |
713 | FOR_EACH_PHI_ARG (use_p, stmt, iter, SSA_OP_USE) | |
714 | { | |
715 | val = USE_FROM_PTR (use_p); | |
716 | if (TREE_CODE (val) != SSA_NAME) | |
717 | continue; | |
718 | if (!add_dependency (val, lim_data, loop, false)) | |
719 | return false; | |
720 | def_data = get_lim_data (SSA_NAME_DEF_STMT (val)); | |
721 | if (def_data) | |
722 | { | |
723 | min_cost = MIN (min_cost, def_data->cost); | |
724 | total_cost += def_data->cost; | |
725 | } | |
726 | } | |
727 | ||
728 | lim_data->cost += min_cost; | |
729 | ||
730 | if (gimple_phi_num_args (stmt) > 1) | |
731 | { | |
732 | basic_block dom = get_immediate_dominator (CDI_DOMINATORS, bb); | |
733 | gimple cond; | |
734 | if (gsi_end_p (gsi_last_bb (dom))) | |
735 | return false; | |
736 | cond = gsi_stmt (gsi_last_bb (dom)); | |
737 | if (gimple_code (cond) != GIMPLE_COND) | |
738 | return false; | |
739 | /* Verify that this is an extended form of a diamond and | |
740 | the PHI arguments are completely controlled by the | |
741 | predicate in DOM. */ | |
742 | if (!extract_true_false_args_from_phi (dom, stmt, NULL, NULL)) | |
743 | return false; | |
744 | ||
745 | /* Fold in dependencies and cost of the condition. */ | |
746 | FOR_EACH_SSA_TREE_OPERAND (val, cond, iter, SSA_OP_USE) | |
747 | { | |
748 | if (!add_dependency (val, lim_data, loop, false)) | |
749 | return false; | |
750 | def_data = get_lim_data (SSA_NAME_DEF_STMT (val)); | |
751 | if (def_data) | |
752 | total_cost += def_data->cost; | |
753 | } | |
754 | ||
755 | /* We want to avoid unconditionally executing very expensive | |
756 | operations. As costs for our dependencies cannot be | |
757 | negative just claim we are not invariand for this case. | |
758 | We also are not sure whether the control-flow inside the | |
759 | loop will vanish. */ | |
760 | if (total_cost - min_cost >= 2 * LIM_EXPENSIVE | |
761 | && !(min_cost != 0 | |
762 | && total_cost / min_cost <= 2)) | |
763 | return false; | |
764 | ||
765 | /* Assume that the control-flow in the loop will vanish. | |
766 | ??? We should verify this and not artificially increase | |
767 | the cost if that is not the case. */ | |
768 | lim_data->cost += stmt_cost (stmt); | |
769 | } | |
770 | ||
771 | return true; | |
772 | } | |
773 | else | |
774 | FOR_EACH_SSA_TREE_OPERAND (val, stmt, iter, SSA_OP_USE) | |
775 | if (!add_dependency (val, lim_data, loop, true)) | |
776 | return false; | |
7d23383d | 777 | |
dd277d48 | 778 | if (gimple_vuse (stmt)) |
063a8bce | 779 | { |
780 | mem_ref_p ref = mem_ref_in_stmt (stmt); | |
781 | ||
782 | if (ref) | |
783 | { | |
784 | lim_data->max_loop | |
785 | = outermost_indep_loop (lim_data->max_loop, loop, ref); | |
786 | if (!lim_data->max_loop) | |
787 | return false; | |
788 | } | |
789 | else | |
790 | { | |
dd277d48 | 791 | if ((val = gimple_vuse (stmt)) != NULL_TREE) |
063a8bce | 792 | { |
793 | if (!add_dependency (val, lim_data, loop, false)) | |
794 | return false; | |
795 | } | |
796 | } | |
797 | } | |
7d23383d | 798 | |
799 | lim_data->cost += stmt_cost (stmt); | |
800 | ||
801 | return true; | |
802 | } | |
803 | ||
804 | /* Suppose that some statement in ORIG_LOOP is hoisted to the loop LEVEL, | |
805 | and that one of the operands of this statement is computed by STMT. | |
806 | Ensure that STMT (together with all the statements that define its | |
807 | operands) is hoisted at least out of the loop LEVEL. */ | |
808 | ||
809 | static void | |
75a70cf9 | 810 | set_level (gimple stmt, struct loop *orig_loop, struct loop *level) |
7d23383d | 811 | { |
75a70cf9 | 812 | struct loop *stmt_loop = gimple_bb (stmt)->loop_father; |
75a70cf9 | 813 | struct lim_aux_data *lim_data; |
a2c22c0d | 814 | gimple dep_stmt; |
815 | unsigned i; | |
7d23383d | 816 | |
817 | stmt_loop = find_common_loop (orig_loop, stmt_loop); | |
75a70cf9 | 818 | lim_data = get_lim_data (stmt); |
819 | if (lim_data != NULL && lim_data->tgt_loop != NULL) | |
7d23383d | 820 | stmt_loop = find_common_loop (stmt_loop, |
75a70cf9 | 821 | loop_outer (lim_data->tgt_loop)); |
7d23383d | 822 | if (flow_loop_nested_p (stmt_loop, level)) |
823 | return; | |
824 | ||
75a70cf9 | 825 | gcc_assert (level == lim_data->max_loop |
826 | || flow_loop_nested_p (lim_data->max_loop, level)); | |
7d23383d | 827 | |
75a70cf9 | 828 | lim_data->tgt_loop = level; |
a2c22c0d | 829 | FOR_EACH_VEC_ELT (lim_data->depends, i, dep_stmt) |
830 | set_level (dep_stmt, orig_loop, level); | |
7d23383d | 831 | } |
832 | ||
833 | /* Determines an outermost loop from that we want to hoist the statement STMT. | |
834 | For now we chose the outermost possible loop. TODO -- use profiling | |
835 | information to set it more sanely. */ | |
836 | ||
837 | static void | |
75a70cf9 | 838 | set_profitable_level (gimple stmt) |
7d23383d | 839 | { |
75a70cf9 | 840 | set_level (stmt, gimple_bb (stmt)->loop_father, get_lim_data (stmt)->max_loop); |
7d23383d | 841 | } |
842 | ||
75a70cf9 | 843 | /* Returns true if STMT is a call that has side effects. */ |
7d23383d | 844 | |
845 | static bool | |
75a70cf9 | 846 | nonpure_call_p (gimple stmt) |
7d23383d | 847 | { |
75a70cf9 | 848 | if (gimple_code (stmt) != GIMPLE_CALL) |
7d23383d | 849 | return false; |
850 | ||
75a70cf9 | 851 | return gimple_has_side_effects (stmt); |
7d23383d | 852 | } |
853 | ||
790963ba | 854 | /* Rewrite a/b to a*(1/b). Return the invariant stmt to process. */ |
855 | ||
75a70cf9 | 856 | static gimple |
857 | rewrite_reciprocal (gimple_stmt_iterator *bsi) | |
790963ba | 858 | { |
75a70cf9 | 859 | gimple stmt, stmt1, stmt2; |
03d37e4e | 860 | tree name, lhs, type; |
193b8a15 | 861 | tree real_one; |
688ff29b | 862 | gimple_stmt_iterator gsi; |
790963ba | 863 | |
75a70cf9 | 864 | stmt = gsi_stmt (*bsi); |
865 | lhs = gimple_assign_lhs (stmt); | |
866 | type = TREE_TYPE (lhs); | |
790963ba | 867 | |
74560f89 | 868 | real_one = build_one_cst (type); |
790963ba | 869 | |
03d37e4e | 870 | name = make_temp_ssa_name (type, NULL, "reciptmp"); |
871 | stmt1 = gimple_build_assign_with_ops (RDIV_EXPR, name, real_one, | |
872 | gimple_assign_rhs2 (stmt)); | |
75a70cf9 | 873 | |
874 | stmt2 = gimple_build_assign_with_ops (MULT_EXPR, lhs, name, | |
875 | gimple_assign_rhs1 (stmt)); | |
790963ba | 876 | |
877 | /* Replace division stmt with reciprocal and multiply stmts. | |
878 | The multiply stmt is not invariant, so update iterator | |
879 | and avoid rescanning. */ | |
688ff29b | 880 | gsi = *bsi; |
881 | gsi_insert_before (bsi, stmt1, GSI_NEW_STMT); | |
882 | gsi_replace (&gsi, stmt2, true); | |
790963ba | 883 | |
884 | /* Continue processing with invariant reciprocal statement. */ | |
885 | return stmt1; | |
886 | } | |
887 | ||
888 | /* Check if the pattern at *BSI is a bittest of the form | |
889 | (A >> B) & 1 != 0 and in this case rewrite it to A & (1 << B) != 0. */ | |
890 | ||
75a70cf9 | 891 | static gimple |
892 | rewrite_bittest (gimple_stmt_iterator *bsi) | |
790963ba | 893 | { |
75a70cf9 | 894 | gimple stmt, use_stmt, stmt1, stmt2; |
03d37e4e | 895 | tree lhs, name, t, a, b; |
790963ba | 896 | use_operand_p use; |
897 | ||
75a70cf9 | 898 | stmt = gsi_stmt (*bsi); |
899 | lhs = gimple_assign_lhs (stmt); | |
790963ba | 900 | |
901 | /* Verify that the single use of lhs is a comparison against zero. */ | |
902 | if (TREE_CODE (lhs) != SSA_NAME | |
27dc0bdf | 903 | || !single_imm_use (lhs, &use, &use_stmt) |
75a70cf9 | 904 | || gimple_code (use_stmt) != GIMPLE_COND) |
790963ba | 905 | return stmt; |
75a70cf9 | 906 | if (gimple_cond_lhs (use_stmt) != lhs |
907 | || (gimple_cond_code (use_stmt) != NE_EXPR | |
908 | && gimple_cond_code (use_stmt) != EQ_EXPR) | |
909 | || !integer_zerop (gimple_cond_rhs (use_stmt))) | |
790963ba | 910 | return stmt; |
911 | ||
912 | /* Get at the operands of the shift. The rhs is TMP1 & 1. */ | |
75a70cf9 | 913 | stmt1 = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (stmt)); |
914 | if (gimple_code (stmt1) != GIMPLE_ASSIGN) | |
790963ba | 915 | return stmt; |
916 | ||
bef304b8 | 917 | /* There is a conversion in between possibly inserted by fold. */ |
d9659041 | 918 | if (CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt1))) |
790963ba | 919 | { |
75a70cf9 | 920 | t = gimple_assign_rhs1 (stmt1); |
790963ba | 921 | if (TREE_CODE (t) != SSA_NAME |
922 | || !has_single_use (t)) | |
923 | return stmt; | |
924 | stmt1 = SSA_NAME_DEF_STMT (t); | |
75a70cf9 | 925 | if (gimple_code (stmt1) != GIMPLE_ASSIGN) |
790963ba | 926 | return stmt; |
790963ba | 927 | } |
928 | ||
929 | /* Verify that B is loop invariant but A is not. Verify that with | |
930 | all the stmt walking we are still in the same loop. */ | |
75a70cf9 | 931 | if (gimple_assign_rhs_code (stmt1) != RSHIFT_EXPR |
932 | || loop_containing_stmt (stmt1) != loop_containing_stmt (stmt)) | |
933 | return stmt; | |
790963ba | 934 | |
75a70cf9 | 935 | a = gimple_assign_rhs1 (stmt1); |
936 | b = gimple_assign_rhs2 (stmt1); | |
937 | ||
938 | if (outermost_invariant_loop (b, loop_containing_stmt (stmt1)) != NULL | |
939 | && outermost_invariant_loop (a, loop_containing_stmt (stmt1)) == NULL) | |
940 | { | |
688ff29b | 941 | gimple_stmt_iterator rsi; |
942 | ||
790963ba | 943 | /* 1 << B */ |
790963ba | 944 | t = fold_build2 (LSHIFT_EXPR, TREE_TYPE (a), |
945 | build_int_cst (TREE_TYPE (a), 1), b); | |
03d37e4e | 946 | name = make_temp_ssa_name (TREE_TYPE (a), NULL, "shifttmp"); |
947 | stmt1 = gimple_build_assign (name, t); | |
790963ba | 948 | |
949 | /* A & (1 << B) */ | |
950 | t = fold_build2 (BIT_AND_EXPR, TREE_TYPE (a), a, name); | |
03d37e4e | 951 | name = make_temp_ssa_name (TREE_TYPE (a), NULL, "shifttmp"); |
952 | stmt2 = gimple_build_assign (name, t); | |
3de988b5 | 953 | |
954 | /* Replace the SSA_NAME we compare against zero. Adjust | |
955 | the type of zero accordingly. */ | |
27dc0bdf | 956 | SET_USE (use, name); |
75a70cf9 | 957 | gimple_cond_set_rhs (use_stmt, build_int_cst_type (TREE_TYPE (name), 0)); |
790963ba | 958 | |
688ff29b | 959 | /* Don't use gsi_replace here, none of the new assignments sets |
960 | the variable originally set in stmt. Move bsi to stmt1, and | |
961 | then remove the original stmt, so that we get a chance to | |
962 | retain debug info for it. */ | |
963 | rsi = *bsi; | |
964 | gsi_insert_before (bsi, stmt1, GSI_NEW_STMT); | |
965 | gsi_insert_before (&rsi, stmt2, GSI_SAME_STMT); | |
966 | gsi_remove (&rsi, true); | |
790963ba | 967 | |
968 | return stmt1; | |
969 | } | |
970 | ||
971 | return stmt; | |
972 | } | |
973 | ||
54c91640 | 974 | /* For each statement determines the outermost loop in that it is invariant, |
975 | - statements on whose motion it depends and the cost of the computation. | |
976 | - This information is stored to the LIM_DATA structure associated with | |
977 | - each statement. */ | |
978 | class invariantness_dom_walker : public dom_walker | |
979 | { | |
980 | public: | |
981 | invariantness_dom_walker (cdi_direction direction) | |
982 | : dom_walker (direction) {} | |
983 | ||
984 | virtual void before_dom_children (basic_block); | |
985 | }; | |
790963ba | 986 | |
7d23383d | 987 | /* Determine the outermost loops in that statements in basic block BB are |
988 | invariant, and record them to the LIM_DATA associated with the statements. | |
54c91640 | 989 | Callback for dom_walker. */ |
7d23383d | 990 | |
54c91640 | 991 | void |
992 | invariantness_dom_walker::before_dom_children (basic_block bb) | |
7d23383d | 993 | { |
994 | enum move_pos pos; | |
75a70cf9 | 995 | gimple_stmt_iterator bsi; |
996 | gimple stmt; | |
7d23383d | 997 | bool maybe_never = ALWAYS_EXECUTED_IN (bb) == NULL; |
998 | struct loop *outermost = ALWAYS_EXECUTED_IN (bb); | |
75a70cf9 | 999 | struct lim_aux_data *lim_data; |
7d23383d | 1000 | |
9e3536f4 | 1001 | if (!loop_outer (bb->loop_father)) |
7d23383d | 1002 | return; |
1003 | ||
1004 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1005 | fprintf (dump_file, "Basic block %d (loop %d -- depth %d):\n\n", | |
9e3536f4 | 1006 | bb->index, bb->loop_father->num, loop_depth (bb->loop_father)); |
7d23383d | 1007 | |
9bf0a3f9 | 1008 | /* Look at PHI nodes, but only if there is at most two. |
1009 | ??? We could relax this further by post-processing the inserted | |
1010 | code and transforming adjacent cond-exprs with the same predicate | |
1011 | to control flow again. */ | |
1012 | bsi = gsi_start_phis (bb); | |
1013 | if (!gsi_end_p (bsi) | |
1014 | && ((gsi_next (&bsi), gsi_end_p (bsi)) | |
1015 | || (gsi_next (&bsi), gsi_end_p (bsi)))) | |
1016 | for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
1017 | { | |
1018 | stmt = gsi_stmt (bsi); | |
1019 | ||
1020 | pos = movement_possibility (stmt); | |
1021 | if (pos == MOVE_IMPOSSIBLE) | |
1022 | continue; | |
1023 | ||
1024 | lim_data = init_lim_data (stmt); | |
1025 | lim_data->always_executed_in = outermost; | |
1026 | ||
1027 | if (!determine_max_movement (stmt, false)) | |
1028 | { | |
1029 | lim_data->max_loop = NULL; | |
1030 | continue; | |
1031 | } | |
1032 | ||
1033 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1034 | { | |
1035 | print_gimple_stmt (dump_file, stmt, 2, 0); | |
1036 | fprintf (dump_file, " invariant up to level %d, cost %d.\n\n", | |
1037 | loop_depth (lim_data->max_loop), | |
1038 | lim_data->cost); | |
1039 | } | |
1040 | ||
1041 | if (lim_data->cost >= LIM_EXPENSIVE) | |
1042 | set_profitable_level (stmt); | |
1043 | } | |
1044 | ||
75a70cf9 | 1045 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
7d23383d | 1046 | { |
75a70cf9 | 1047 | stmt = gsi_stmt (bsi); |
7d23383d | 1048 | |
1049 | pos = movement_possibility (stmt); | |
1050 | if (pos == MOVE_IMPOSSIBLE) | |
1051 | { | |
1052 | if (nonpure_call_p (stmt)) | |
1053 | { | |
1054 | maybe_never = true; | |
1055 | outermost = NULL; | |
1056 | } | |
a973ed42 | 1057 | /* Make sure to note always_executed_in for stores to make |
1058 | store-motion work. */ | |
1059 | else if (stmt_makes_single_store (stmt)) | |
1060 | { | |
75a70cf9 | 1061 | struct lim_aux_data *lim_data = init_lim_data (stmt); |
1062 | lim_data->always_executed_in = outermost; | |
a973ed42 | 1063 | } |
7d23383d | 1064 | continue; |
1065 | } | |
1066 | ||
75a70cf9 | 1067 | if (is_gimple_assign (stmt) |
1068 | && (get_gimple_rhs_class (gimple_assign_rhs_code (stmt)) | |
1069 | == GIMPLE_BINARY_RHS)) | |
63f88450 | 1070 | { |
75a70cf9 | 1071 | tree op0 = gimple_assign_rhs1 (stmt); |
1072 | tree op1 = gimple_assign_rhs2 (stmt); | |
1073 | struct loop *ol1 = outermost_invariant_loop (op1, | |
1074 | loop_containing_stmt (stmt)); | |
63f88450 | 1075 | |
1076 | /* If divisor is invariant, convert a/b to a*(1/b), allowing reciprocal | |
1077 | to be hoisted out of loop, saving expensive divide. */ | |
1078 | if (pos == MOVE_POSSIBLE | |
75a70cf9 | 1079 | && gimple_assign_rhs_code (stmt) == RDIV_EXPR |
63f88450 | 1080 | && flag_unsafe_math_optimizations |
1081 | && !flag_trapping_math | |
75a70cf9 | 1082 | && ol1 != NULL |
1083 | && outermost_invariant_loop (op0, ol1) == NULL) | |
63f88450 | 1084 | stmt = rewrite_reciprocal (&bsi); |
1085 | ||
1086 | /* If the shift count is invariant, convert (A >> B) & 1 to | |
1087 | A & (1 << B) allowing the bit mask to be hoisted out of the loop | |
1088 | saving an expensive shift. */ | |
1089 | if (pos == MOVE_POSSIBLE | |
75a70cf9 | 1090 | && gimple_assign_rhs_code (stmt) == BIT_AND_EXPR |
1091 | && integer_onep (op1) | |
1092 | && TREE_CODE (op0) == SSA_NAME | |
1093 | && has_single_use (op0)) | |
63f88450 | 1094 | stmt = rewrite_bittest (&bsi); |
1095 | } | |
fcee97ca | 1096 | |
75a70cf9 | 1097 | lim_data = init_lim_data (stmt); |
1098 | lim_data->always_executed_in = outermost; | |
7d23383d | 1099 | |
1100 | if (maybe_never && pos == MOVE_PRESERVE_EXECUTION) | |
1101 | continue; | |
1102 | ||
1103 | if (!determine_max_movement (stmt, pos == MOVE_PRESERVE_EXECUTION)) | |
1104 | { | |
75a70cf9 | 1105 | lim_data->max_loop = NULL; |
7d23383d | 1106 | continue; |
1107 | } | |
1108 | ||
1109 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1110 | { | |
75a70cf9 | 1111 | print_gimple_stmt (dump_file, stmt, 2, 0); |
7d23383d | 1112 | fprintf (dump_file, " invariant up to level %d, cost %d.\n\n", |
75a70cf9 | 1113 | loop_depth (lim_data->max_loop), |
1114 | lim_data->cost); | |
7d23383d | 1115 | } |
1116 | ||
75a70cf9 | 1117 | if (lim_data->cost >= LIM_EXPENSIVE) |
7d23383d | 1118 | set_profitable_level (stmt); |
1119 | } | |
1120 | } | |
1121 | ||
54c91640 | 1122 | class move_computations_dom_walker : public dom_walker |
7d23383d | 1123 | { |
54c91640 | 1124 | public: |
1125 | move_computations_dom_walker (cdi_direction direction) | |
1126 | : dom_walker (direction), todo_ (0) {} | |
7d23383d | 1127 | |
54c91640 | 1128 | virtual void before_dom_children (basic_block); |
7d23383d | 1129 | |
54c91640 | 1130 | unsigned int todo_; |
1131 | }; | |
7d23383d | 1132 | |
bc228ba1 | 1133 | /* Return true if CODE is an operation that when operating on signed |
1134 | integer types involves undefined behavior on overflow and the | |
1135 | operation can be expressed with unsigned arithmetic. */ | |
1136 | ||
1137 | static bool | |
1138 | arith_code_with_undefined_signed_overflow (tree_code code) | |
1139 | { | |
1140 | switch (code) | |
1141 | { | |
1142 | case PLUS_EXPR: | |
1143 | case MINUS_EXPR: | |
1144 | case MULT_EXPR: | |
1145 | case NEGATE_EXPR: | |
1146 | case POINTER_PLUS_EXPR: | |
1147 | return true; | |
1148 | default: | |
1149 | return false; | |
1150 | } | |
1151 | } | |
1152 | ||
1153 | /* Rewrite STMT, an assignment with a signed integer or pointer arithmetic | |
1154 | operation that can be transformed to unsigned arithmetic by converting | |
1155 | its operand, carrying out the operation in the corresponding unsigned | |
1156 | type and converting the result back to the original type. | |
1157 | ||
1158 | Returns a sequence of statements that replace STMT and also contain | |
1159 | a modified form of STMT itself. */ | |
1160 | ||
1161 | static gimple_seq | |
1162 | rewrite_to_defined_overflow (gimple stmt) | |
1163 | { | |
1164 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1165 | { | |
1166 | fprintf (dump_file, "rewriting stmt with undefined signed " | |
1167 | "overflow "); | |
1168 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1169 | } | |
1170 | ||
1171 | tree lhs = gimple_assign_lhs (stmt); | |
1172 | tree type = unsigned_type_for (TREE_TYPE (lhs)); | |
1173 | gimple_seq stmts = NULL; | |
1174 | for (unsigned i = 1; i < gimple_num_ops (stmt); ++i) | |
1175 | { | |
1176 | gimple_seq stmts2 = NULL; | |
1177 | gimple_set_op (stmt, i, | |
1178 | force_gimple_operand (fold_convert (type, | |
1179 | gimple_op (stmt, i)), | |
1180 | &stmts2, true, NULL_TREE)); | |
1181 | gimple_seq_add_seq (&stmts, stmts2); | |
1182 | } | |
1183 | gimple_assign_set_lhs (stmt, make_ssa_name (type, stmt)); | |
1184 | if (gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR) | |
1185 | gimple_assign_set_rhs_code (stmt, PLUS_EXPR); | |
1186 | gimple_seq_add_stmt (&stmts, stmt); | |
1187 | gimple cvt = gimple_build_assign_with_ops | |
1188 | (NOP_EXPR, lhs, gimple_assign_lhs (stmt), NULL_TREE); | |
1189 | gimple_seq_add_stmt (&stmts, cvt); | |
1190 | ||
1191 | return stmts; | |
1192 | } | |
1193 | ||
7d23383d | 1194 | /* Hoist the statements in basic block BB out of the loops prescribed by |
91275768 | 1195 | data stored in LIM_DATA structures associated with each statement. Callback |
7d23383d | 1196 | for walk_dominator_tree. */ |
1197 | ||
54c91640 | 1198 | void |
1199 | move_computations_dom_walker::before_dom_children (basic_block bb) | |
7d23383d | 1200 | { |
1201 | struct loop *level; | |
75a70cf9 | 1202 | gimple_stmt_iterator bsi; |
1203 | gimple stmt; | |
7d23383d | 1204 | unsigned cost = 0; |
75a70cf9 | 1205 | struct lim_aux_data *lim_data; |
7d23383d | 1206 | |
9e3536f4 | 1207 | if (!loop_outer (bb->loop_father)) |
7d23383d | 1208 | return; |
1209 | ||
9bf0a3f9 | 1210 | for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); ) |
1211 | { | |
1212 | gimple new_stmt; | |
1213 | stmt = gsi_stmt (bsi); | |
1214 | ||
1215 | lim_data = get_lim_data (stmt); | |
1216 | if (lim_data == NULL) | |
1217 | { | |
1218 | gsi_next (&bsi); | |
1219 | continue; | |
1220 | } | |
1221 | ||
1222 | cost = lim_data->cost; | |
1223 | level = lim_data->tgt_loop; | |
1224 | clear_lim_data (stmt); | |
1225 | ||
1226 | if (!level) | |
1227 | { | |
1228 | gsi_next (&bsi); | |
1229 | continue; | |
1230 | } | |
1231 | ||
1232 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1233 | { | |
1234 | fprintf (dump_file, "Moving PHI node\n"); | |
1235 | print_gimple_stmt (dump_file, stmt, 0, 0); | |
1236 | fprintf (dump_file, "(cost %u) out of loop %d.\n\n", | |
1237 | cost, level->num); | |
1238 | } | |
1239 | ||
1240 | if (gimple_phi_num_args (stmt) == 1) | |
1241 | { | |
1242 | tree arg = PHI_ARG_DEF (stmt, 0); | |
1243 | new_stmt = gimple_build_assign_with_ops (TREE_CODE (arg), | |
1244 | gimple_phi_result (stmt), | |
1245 | arg, NULL_TREE); | |
9bf0a3f9 | 1246 | } |
1247 | else | |
1248 | { | |
1249 | basic_block dom = get_immediate_dominator (CDI_DOMINATORS, bb); | |
1250 | gimple cond = gsi_stmt (gsi_last_bb (dom)); | |
1251 | tree arg0 = NULL_TREE, arg1 = NULL_TREE, t; | |
1252 | /* Get the PHI arguments corresponding to the true and false | |
1253 | edges of COND. */ | |
1254 | extract_true_false_args_from_phi (dom, stmt, &arg0, &arg1); | |
1255 | gcc_assert (arg0 && arg1); | |
1256 | t = build2 (gimple_cond_code (cond), boolean_type_node, | |
1257 | gimple_cond_lhs (cond), gimple_cond_rhs (cond)); | |
446e85eb | 1258 | new_stmt = gimple_build_assign_with_ops (COND_EXPR, |
1259 | gimple_phi_result (stmt), | |
1260 | t, arg0, arg1); | |
54c91640 | 1261 | todo_ |= TODO_cleanup_cfg; |
9bf0a3f9 | 1262 | } |
1263 | gsi_insert_on_edge (loop_preheader_edge (level), new_stmt); | |
1264 | remove_phi_node (&bsi, false); | |
1265 | } | |
1266 | ||
75a70cf9 | 1267 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); ) |
7d23383d | 1268 | { |
e70e8b13 | 1269 | edge e; |
1270 | ||
75a70cf9 | 1271 | stmt = gsi_stmt (bsi); |
7d23383d | 1272 | |
75a70cf9 | 1273 | lim_data = get_lim_data (stmt); |
1274 | if (lim_data == NULL) | |
7d23383d | 1275 | { |
75a70cf9 | 1276 | gsi_next (&bsi); |
7d23383d | 1277 | continue; |
1278 | } | |
1279 | ||
75a70cf9 | 1280 | cost = lim_data->cost; |
1281 | level = lim_data->tgt_loop; | |
1282 | clear_lim_data (stmt); | |
7d23383d | 1283 | |
1284 | if (!level) | |
1285 | { | |
75a70cf9 | 1286 | gsi_next (&bsi); |
7d23383d | 1287 | continue; |
1288 | } | |
1289 | ||
1290 | /* We do not really want to move conditionals out of the loop; we just | |
1291 | placed it here to force its operands to be moved if necessary. */ | |
75a70cf9 | 1292 | if (gimple_code (stmt) == GIMPLE_COND) |
7d23383d | 1293 | continue; |
1294 | ||
1295 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1296 | { | |
1297 | fprintf (dump_file, "Moving statement\n"); | |
75a70cf9 | 1298 | print_gimple_stmt (dump_file, stmt, 0, 0); |
7d23383d | 1299 | fprintf (dump_file, "(cost %u) out of loop %d.\n\n", |
1300 | cost, level->num); | |
1301 | } | |
063a8bce | 1302 | |
e70e8b13 | 1303 | e = loop_preheader_edge (level); |
1304 | gcc_assert (!gimple_vdef (stmt)); | |
1305 | if (gimple_vuse (stmt)) | |
1306 | { | |
1307 | /* The new VUSE is the one from the virtual PHI in the loop | |
1308 | header or the one already present. */ | |
1309 | gimple_stmt_iterator gsi2; | |
1310 | for (gsi2 = gsi_start_phis (e->dest); | |
1311 | !gsi_end_p (gsi2); gsi_next (&gsi2)) | |
1312 | { | |
1313 | gimple phi = gsi_stmt (gsi2); | |
7c782c9b | 1314 | if (virtual_operand_p (gimple_phi_result (phi))) |
e70e8b13 | 1315 | { |
1316 | gimple_set_vuse (stmt, PHI_ARG_DEF_FROM_EDGE (phi, e)); | |
1317 | break; | |
1318 | } | |
1319 | } | |
1320 | } | |
75a70cf9 | 1321 | gsi_remove (&bsi, false); |
bc228ba1 | 1322 | /* In case this is a stmt that is not unconditionally executed |
1323 | when the target loop header is executed and the stmt may | |
1324 | invoke undefined integer or pointer overflow rewrite it to | |
1325 | unsigned arithmetic. */ | |
1326 | if (is_gimple_assign (stmt) | |
1327 | && INTEGRAL_TYPE_P (TREE_TYPE (gimple_assign_lhs (stmt))) | |
1328 | && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (gimple_assign_lhs (stmt))) | |
1329 | && arith_code_with_undefined_signed_overflow | |
1330 | (gimple_assign_rhs_code (stmt)) | |
1331 | && (!ALWAYS_EXECUTED_IN (bb) | |
1332 | || !(ALWAYS_EXECUTED_IN (bb) == level | |
1333 | || flow_loop_nested_p (ALWAYS_EXECUTED_IN (bb), level)))) | |
1334 | gsi_insert_seq_on_edge (e, rewrite_to_defined_overflow (stmt)); | |
1335 | else | |
1336 | gsi_insert_on_edge (e, stmt); | |
7d23383d | 1337 | } |
1338 | } | |
1339 | ||
1340 | /* Hoist the statements out of the loops prescribed by data stored in | |
91275768 | 1341 | LIM_DATA structures associated with each statement.*/ |
7d23383d | 1342 | |
9bf0a3f9 | 1343 | static unsigned int |
7d23383d | 1344 | move_computations (void) |
1345 | { | |
54c91640 | 1346 | move_computations_dom_walker walker (CDI_DOMINATORS); |
1347 | walker.walk (cfun->cfg->x_entry_block_ptr); | |
7d23383d | 1348 | |
75a70cf9 | 1349 | gsi_commit_edge_inserts (); |
dd277d48 | 1350 | if (need_ssa_update_p (cfun)) |
095dcfa3 | 1351 | rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); |
9bf0a3f9 | 1352 | |
54c91640 | 1353 | return walker.todo_; |
7d23383d | 1354 | } |
1355 | ||
1356 | /* Checks whether the statement defining variable *INDEX can be hoisted | |
1357 | out of the loop passed in DATA. Callback for for_each_index. */ | |
1358 | ||
1359 | static bool | |
1360 | may_move_till (tree ref, tree *index, void *data) | |
1361 | { | |
75a70cf9 | 1362 | struct loop *loop = (struct loop *) data, *max_loop; |
7d23383d | 1363 | |
1364 | /* If REF is an array reference, check also that the step and the lower | |
1365 | bound is invariant in LOOP. */ | |
1366 | if (TREE_CODE (ref) == ARRAY_REF) | |
1367 | { | |
75a70cf9 | 1368 | tree step = TREE_OPERAND (ref, 3); |
1369 | tree lbound = TREE_OPERAND (ref, 2); | |
7d23383d | 1370 | |
75a70cf9 | 1371 | max_loop = outermost_invariant_loop (step, loop); |
7d23383d | 1372 | if (!max_loop) |
1373 | return false; | |
1374 | ||
75a70cf9 | 1375 | max_loop = outermost_invariant_loop (lbound, loop); |
7d23383d | 1376 | if (!max_loop) |
1377 | return false; | |
1378 | } | |
1379 | ||
1380 | max_loop = outermost_invariant_loop (*index, loop); | |
1381 | if (!max_loop) | |
1382 | return false; | |
1383 | ||
1384 | return true; | |
1385 | } | |
1386 | ||
75a70cf9 | 1387 | /* If OP is SSA NAME, force the statement that defines it to be |
99e96094 | 1388 | moved out of the LOOP. ORIG_LOOP is the loop in that EXPR is used. */ |
7d23383d | 1389 | |
1390 | static void | |
75a70cf9 | 1391 | force_move_till_op (tree op, struct loop *orig_loop, struct loop *loop) |
7d23383d | 1392 | { |
75a70cf9 | 1393 | gimple stmt; |
7d23383d | 1394 | |
75a70cf9 | 1395 | if (!op |
1396 | || is_gimple_min_invariant (op)) | |
1397 | return; | |
7d23383d | 1398 | |
75a70cf9 | 1399 | gcc_assert (TREE_CODE (op) == SSA_NAME); |
48e1416a | 1400 | |
75a70cf9 | 1401 | stmt = SSA_NAME_DEF_STMT (op); |
1402 | if (gimple_nop_p (stmt)) | |
7d23383d | 1403 | return; |
1404 | ||
75a70cf9 | 1405 | set_level (stmt, orig_loop, loop); |
7d23383d | 1406 | } |
1407 | ||
1408 | /* Forces statement defining invariants in REF (and *INDEX) to be moved out of | |
99e96094 | 1409 | the LOOP. The reference REF is used in the loop ORIG_LOOP. Callback for |
1410 | for_each_index. */ | |
1411 | ||
1412 | struct fmt_data | |
1413 | { | |
1414 | struct loop *loop; | |
1415 | struct loop *orig_loop; | |
1416 | }; | |
7d23383d | 1417 | |
1418 | static bool | |
1419 | force_move_till (tree ref, tree *index, void *data) | |
1420 | { | |
f0d6e81c | 1421 | struct fmt_data *fmt_data = (struct fmt_data *) data; |
7d23383d | 1422 | |
1423 | if (TREE_CODE (ref) == ARRAY_REF) | |
1424 | { | |
75a70cf9 | 1425 | tree step = TREE_OPERAND (ref, 3); |
1426 | tree lbound = TREE_OPERAND (ref, 2); | |
7d23383d | 1427 | |
75a70cf9 | 1428 | force_move_till_op (step, fmt_data->orig_loop, fmt_data->loop); |
1429 | force_move_till_op (lbound, fmt_data->orig_loop, fmt_data->loop); | |
7d23383d | 1430 | } |
1431 | ||
75a70cf9 | 1432 | force_move_till_op (*index, fmt_data->orig_loop, fmt_data->loop); |
7d23383d | 1433 | |
1434 | return true; | |
1435 | } | |
1436 | ||
063a8bce | 1437 | /* A function to free the mem_ref object OBJ. */ |
1438 | ||
1439 | static void | |
83b709f2 | 1440 | memref_free (struct mem_ref *mem) |
063a8bce | 1441 | { |
063a8bce | 1442 | unsigned i; |
5c8a8be3 | 1443 | vec<mem_ref_loc> *accs; |
063a8bce | 1444 | |
f1f41a6c | 1445 | FOR_EACH_VEC_ELT (mem->accesses_in_loop, i, accs) |
5c8a8be3 | 1446 | accs->release (); |
f1f41a6c | 1447 | mem->accesses_in_loop.release (); |
063a8bce | 1448 | |
063a8bce | 1449 | free (mem); |
1450 | } | |
1451 | ||
1452 | /* Allocates and returns a memory reference description for MEM whose hash | |
1453 | value is HASH and id is ID. */ | |
1454 | ||
1455 | static mem_ref_p | |
1456 | mem_ref_alloc (tree mem, unsigned hash, unsigned id) | |
1457 | { | |
1458 | mem_ref_p ref = XNEW (struct mem_ref); | |
09f4cf62 | 1459 | ao_ref_init (&ref->mem, mem); |
063a8bce | 1460 | ref->id = id; |
1461 | ref->hash = hash; | |
feba4360 | 1462 | bitmap_initialize (&ref->stored, &lim_bitmap_obstack); |
1463 | bitmap_initialize (&ref->indep_loop, &lim_bitmap_obstack); | |
1464 | bitmap_initialize (&ref->dep_loop, &lim_bitmap_obstack); | |
f1f41a6c | 1465 | ref->accesses_in_loop.create (0); |
063a8bce | 1466 | |
1467 | return ref; | |
1468 | } | |
1469 | ||
063a8bce | 1470 | /* Records memory reference location *LOC in LOOP to the memory reference |
1471 | description REF. The reference occurs in statement STMT. */ | |
7d23383d | 1472 | |
1473 | static void | |
75a70cf9 | 1474 | record_mem_ref_loc (mem_ref_p ref, struct loop *loop, gimple stmt, tree *loc) |
7d23383d | 1475 | { |
5c8a8be3 | 1476 | mem_ref_loc aref; |
063a8bce | 1477 | |
f1f41a6c | 1478 | if (ref->accesses_in_loop.length () |
063a8bce | 1479 | <= (unsigned) loop->num) |
f1f41a6c | 1480 | ref->accesses_in_loop.safe_grow_cleared (loop->num + 1); |
7d23383d | 1481 | |
5c8a8be3 | 1482 | aref.stmt = stmt; |
1483 | aref.ref = loc; | |
1484 | ref->accesses_in_loop[loop->num].safe_push (aref); | |
7d23383d | 1485 | } |
1486 | ||
063a8bce | 1487 | /* Marks reference REF as stored in LOOP. */ |
7d23383d | 1488 | |
1489 | static void | |
063a8bce | 1490 | mark_ref_stored (mem_ref_p ref, struct loop *loop) |
7d23383d | 1491 | { |
feba4360 | 1492 | while (loop != current_loops->tree_root |
1493 | && bitmap_set_bit (&ref->stored, loop->num)) | |
1494 | loop = loop_outer (loop); | |
063a8bce | 1495 | } |
1496 | ||
1497 | /* Gathers memory references in statement STMT in LOOP, storing the | |
1498 | information about them in the memory_accesses structure. Marks | |
1499 | the vops accessed through unrecognized statements there as | |
1500 | well. */ | |
1501 | ||
1502 | static void | |
75a70cf9 | 1503 | gather_mem_refs_stmt (struct loop *loop, gimple stmt) |
063a8bce | 1504 | { |
1505 | tree *mem = NULL; | |
1506 | hashval_t hash; | |
3e871d4d | 1507 | mem_ref **slot; |
063a8bce | 1508 | mem_ref_p ref; |
063a8bce | 1509 | bool is_stored; |
063a8bce | 1510 | unsigned id; |
7d23383d | 1511 | |
dd277d48 | 1512 | if (!gimple_vuse (stmt)) |
063a8bce | 1513 | return; |
1514 | ||
1515 | mem = simple_mem_ref_in_stmt (stmt, &is_stored); | |
1516 | if (!mem) | |
0766b2c0 | 1517 | { |
04911505 | 1518 | /* We use the shared mem_ref for all unanalyzable refs. */ |
1519 | id = UNANALYZABLE_MEM_ID; | |
1520 | ref = memory_accesses.refs_list[id]; | |
0766b2c0 | 1521 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1522 | { | |
1523 | fprintf (dump_file, "Unanalyzed memory reference %u: ", id); | |
1524 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); | |
1525 | } | |
04911505 | 1526 | is_stored = gimple_vdef (stmt); |
063a8bce | 1527 | } |
1528 | else | |
7d23383d | 1529 | { |
04911505 | 1530 | hash = iterative_hash_expr (*mem, 0); |
3e871d4d | 1531 | slot = memory_accesses.refs.find_slot_with_hash (*mem, hash, INSERT); |
04911505 | 1532 | if (*slot) |
063a8bce | 1533 | { |
04911505 | 1534 | ref = (mem_ref_p) *slot; |
1535 | id = ref->id; | |
063a8bce | 1536 | } |
04911505 | 1537 | else |
1538 | { | |
1539 | id = memory_accesses.refs_list.length (); | |
1540 | ref = mem_ref_alloc (*mem, hash, id); | |
1541 | memory_accesses.refs_list.safe_push (ref); | |
1542 | *slot = ref; | |
61025ec0 | 1543 | |
04911505 | 1544 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1545 | { | |
1546 | fprintf (dump_file, "Memory reference %u: ", id); | |
1547 | print_generic_expr (dump_file, ref->mem.ref, TDF_SLIM); | |
1548 | fprintf (dump_file, "\n"); | |
1549 | } | |
1550 | } | |
1551 | ||
1552 | record_mem_ref_loc (ref, loop, stmt, mem); | |
1553 | } | |
feba4360 | 1554 | bitmap_set_bit (&memory_accesses.refs_in_loop[loop->num], ref->id); |
063a8bce | 1555 | if (is_stored) |
8f9829e8 | 1556 | { |
feba4360 | 1557 | bitmap_set_bit (&memory_accesses.refs_stored_in_loop[loop->num], ref->id); |
8f9829e8 | 1558 | mark_ref_stored (ref, loop); |
1559 | } | |
063a8bce | 1560 | return; |
7d23383d | 1561 | } |
1562 | ||
7894a3d9 | 1563 | static unsigned *bb_loop_postorder; |
1564 | ||
1565 | /* qsort sort function to sort blocks after their loop fathers postorder. */ | |
1566 | ||
1567 | static int | |
1568 | sort_bbs_in_loop_postorder_cmp (const void *bb1_, const void *bb2_) | |
1569 | { | |
1570 | basic_block bb1 = *(basic_block *)const_cast<void *>(bb1_); | |
1571 | basic_block bb2 = *(basic_block *)const_cast<void *>(bb2_); | |
1572 | struct loop *loop1 = bb1->loop_father; | |
1573 | struct loop *loop2 = bb2->loop_father; | |
1574 | if (loop1->num == loop2->num) | |
1575 | return 0; | |
1576 | return bb_loop_postorder[loop1->num] < bb_loop_postorder[loop2->num] ? -1 : 1; | |
1577 | } | |
1578 | ||
063a8bce | 1579 | /* Gathers memory references in loops. */ |
7d23383d | 1580 | |
1581 | static void | |
feba4360 | 1582 | analyze_memory_references (void) |
7d23383d | 1583 | { |
75a70cf9 | 1584 | gimple_stmt_iterator bsi; |
7894a3d9 | 1585 | basic_block bb, *bbs; |
8f9829e8 | 1586 | struct loop *loop, *outer; |
7894a3d9 | 1587 | unsigned i, n; |
063a8bce | 1588 | |
7894a3d9 | 1589 | /* Initialize bb_loop_postorder with a mapping from loop->num to |
1590 | its postorder index. */ | |
1591 | i = 0; | |
41f75a99 | 1592 | bb_loop_postorder = XNEWVEC (unsigned, number_of_loops (cfun)); |
f21d4d00 | 1593 | FOR_EACH_LOOP (loop, LI_FROM_INNERMOST) |
7894a3d9 | 1594 | bb_loop_postorder[loop->num] = i++; |
1595 | /* Collect all basic-blocks in loops and sort them after their | |
1596 | loops postorder. */ | |
1597 | i = 0; | |
a28770e1 | 1598 | bbs = XNEWVEC (basic_block, n_basic_blocks_for_fn (cfun) - NUM_FIXED_BLOCKS); |
063a8bce | 1599 | FOR_EACH_BB (bb) |
7894a3d9 | 1600 | if (bb->loop_father != current_loops->tree_root) |
1601 | bbs[i++] = bb; | |
1602 | n = i; | |
1603 | qsort (bbs, n, sizeof (basic_block), sort_bbs_in_loop_postorder_cmp); | |
1604 | free (bb_loop_postorder); | |
1605 | ||
1606 | /* Visit blocks in loop postorder and assign mem-ref IDs in that order. | |
1607 | That results in better locality for all the bitmaps. */ | |
1608 | for (i = 0; i < n; ++i) | |
063a8bce | 1609 | { |
7894a3d9 | 1610 | basic_block bb = bbs[i]; |
75a70cf9 | 1611 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
7894a3d9 | 1612 | gather_mem_refs_stmt (bb->loop_father, gsi_stmt (bsi)); |
063a8bce | 1613 | } |
1614 | ||
7894a3d9 | 1615 | free (bbs); |
1616 | ||
0766b2c0 | 1617 | /* Propagate the information about accessed memory references up |
1618 | the loop hierarchy. */ | |
f21d4d00 | 1619 | FOR_EACH_LOOP (loop, LI_FROM_INNERMOST) |
063a8bce | 1620 | { |
8f9829e8 | 1621 | /* Finalize the overall touched references (including subloops). */ |
feba4360 | 1622 | bitmap_ior_into (&memory_accesses.all_refs_stored_in_loop[loop->num], |
1623 | &memory_accesses.refs_stored_in_loop[loop->num]); | |
8f9829e8 | 1624 | |
1625 | /* Propagate the information about accessed memory references up | |
1626 | the loop hierarchy. */ | |
1627 | outer = loop_outer (loop); | |
1628 | if (outer == current_loops->tree_root) | |
063a8bce | 1629 | continue; |
1630 | ||
feba4360 | 1631 | bitmap_ior_into (&memory_accesses.all_refs_stored_in_loop[outer->num], |
1632 | &memory_accesses.all_refs_stored_in_loop[loop->num]); | |
063a8bce | 1633 | } |
063a8bce | 1634 | } |
1635 | ||
063a8bce | 1636 | /* Returns true if MEM1 and MEM2 may alias. TTAE_CACHE is used as a cache in |
1637 | tree_to_aff_combination_expand. */ | |
1638 | ||
1639 | static bool | |
09f4cf62 | 1640 | mem_refs_may_alias_p (mem_ref_p mem1, mem_ref_p mem2, |
1641 | struct pointer_map_t **ttae_cache) | |
063a8bce | 1642 | { |
1643 | /* Perform BASE + OFFSET analysis -- if MEM1 and MEM2 are based on the same | |
1644 | object and their offset differ in such a way that the locations cannot | |
1645 | overlap, then they cannot alias. */ | |
063a8bce | 1646 | double_int size1, size2; |
3391cd1e | 1647 | aff_tree off1, off2; |
063a8bce | 1648 | |
3391cd1e | 1649 | /* Perform basic offset and type-based disambiguation. */ |
09f4cf62 | 1650 | if (!refs_may_alias_p_1 (&mem1->mem, &mem2->mem, true)) |
063a8bce | 1651 | return false; |
7d23383d | 1652 | |
063a8bce | 1653 | /* The expansion of addresses may be a bit expensive, thus we only do |
1654 | the check at -O2 and higher optimization levels. */ | |
1655 | if (optimize < 2) | |
1656 | return true; | |
1657 | ||
09f4cf62 | 1658 | get_inner_reference_aff (mem1->mem.ref, &off1, &size1); |
1659 | get_inner_reference_aff (mem2->mem.ref, &off2, &size2); | |
063a8bce | 1660 | aff_combination_expand (&off1, ttae_cache); |
1661 | aff_combination_expand (&off2, ttae_cache); | |
1662 | aff_combination_scale (&off1, double_int_minus_one); | |
1663 | aff_combination_add (&off2, &off1); | |
1664 | ||
5fc88ffd | 1665 | if (aff_comb_cannot_overlap_p (&off2, size1, size2)) |
063a8bce | 1666 | return false; |
1667 | ||
1668 | return true; | |
1669 | } | |
1670 | ||
5c8a8be3 | 1671 | /* Iterates over all locations of REF in LOOP and its subloops calling |
1672 | fn.operator() with the location as argument. When that operator | |
1673 | returns true the iteration is stopped and true is returned. | |
1674 | Otherwise false is returned. */ | |
063a8bce | 1675 | |
5c8a8be3 | 1676 | template <typename FN> |
1677 | static bool | |
1678 | for_all_locs_in_loop (struct loop *loop, mem_ref_p ref, FN fn) | |
063a8bce | 1679 | { |
063a8bce | 1680 | unsigned i; |
1681 | mem_ref_loc_p loc; | |
063a8bce | 1682 | struct loop *subloop; |
1683 | ||
5c8a8be3 | 1684 | if (ref->accesses_in_loop.length () > (unsigned) loop->num) |
1685 | FOR_EACH_VEC_ELT (ref->accesses_in_loop[loop->num], i, loc) | |
1686 | if (fn (loc)) | |
1687 | return true; | |
063a8bce | 1688 | |
1689 | for (subloop = loop->inner; subloop != NULL; subloop = subloop->next) | |
5c8a8be3 | 1690 | if (for_all_locs_in_loop (subloop, ref, fn)) |
1691 | return true; | |
1692 | ||
1693 | return false; | |
1694 | } | |
1695 | ||
1696 | /* Rewrites location LOC by TMP_VAR. */ | |
1697 | ||
1698 | struct rewrite_mem_ref_loc | |
1699 | { | |
1700 | rewrite_mem_ref_loc (tree tmp_var_) : tmp_var (tmp_var_) {} | |
9af5ce0c | 1701 | bool operator () (mem_ref_loc_p loc); |
5c8a8be3 | 1702 | tree tmp_var; |
1703 | }; | |
1704 | ||
1705 | bool | |
9af5ce0c | 1706 | rewrite_mem_ref_loc::operator () (mem_ref_loc_p loc) |
5c8a8be3 | 1707 | { |
1708 | *loc->ref = tmp_var; | |
1709 | update_stmt (loc->stmt); | |
1710 | return false; | |
063a8bce | 1711 | } |
1712 | ||
1713 | /* Rewrites all references to REF in LOOP by variable TMP_VAR. */ | |
1714 | ||
1715 | static void | |
1716 | rewrite_mem_refs (struct loop *loop, mem_ref_p ref, tree tmp_var) | |
1717 | { | |
5c8a8be3 | 1718 | for_all_locs_in_loop (loop, ref, rewrite_mem_ref_loc (tmp_var)); |
7d23383d | 1719 | } |
1720 | ||
bc9af2dd | 1721 | /* Stores the first reference location in LOCP. */ |
1722 | ||
1723 | struct first_mem_ref_loc_1 | |
1724 | { | |
1725 | first_mem_ref_loc_1 (mem_ref_loc_p *locp_) : locp (locp_) {} | |
9af5ce0c | 1726 | bool operator () (mem_ref_loc_p loc); |
bc9af2dd | 1727 | mem_ref_loc_p *locp; |
1728 | }; | |
1729 | ||
1730 | bool | |
9af5ce0c | 1731 | first_mem_ref_loc_1::operator () (mem_ref_loc_p loc) |
bc9af2dd | 1732 | { |
1733 | *locp = loc; | |
1734 | return true; | |
1735 | } | |
1736 | ||
1737 | /* Returns the first reference location to REF in LOOP. */ | |
1738 | ||
1739 | static mem_ref_loc_p | |
1740 | first_mem_ref_loc (struct loop *loop, mem_ref_p ref) | |
1741 | { | |
1742 | mem_ref_loc_p locp = NULL; | |
1743 | for_all_locs_in_loop (loop, ref, first_mem_ref_loc_1 (&locp)); | |
1744 | return locp; | |
1745 | } | |
1746 | ||
61025ec0 | 1747 | struct prev_flag_edges { |
1748 | /* Edge to insert new flag comparison code. */ | |
1749 | edge append_cond_position; | |
1750 | ||
1751 | /* Edge for fall through from previous flag comparison. */ | |
1752 | edge last_cond_fallthru; | |
1753 | }; | |
1754 | ||
1755 | /* Helper function for execute_sm. Emit code to store TMP_VAR into | |
1756 | MEM along edge EX. | |
1757 | ||
1758 | The store is only done if MEM has changed. We do this so no | |
1759 | changes to MEM occur on code paths that did not originally store | |
1760 | into it. | |
1761 | ||
1762 | The common case for execute_sm will transform: | |
1763 | ||
1764 | for (...) { | |
1765 | if (foo) | |
1766 | stuff; | |
1767 | else | |
1768 | MEM = TMP_VAR; | |
1769 | } | |
1770 | ||
1771 | into: | |
1772 | ||
1773 | lsm = MEM; | |
1774 | for (...) { | |
1775 | if (foo) | |
1776 | stuff; | |
1777 | else | |
1778 | lsm = TMP_VAR; | |
1779 | } | |
1780 | MEM = lsm; | |
1781 | ||
1782 | This function will generate: | |
1783 | ||
1784 | lsm = MEM; | |
1785 | ||
1786 | lsm_flag = false; | |
1787 | ... | |
1788 | for (...) { | |
1789 | if (foo) | |
1790 | stuff; | |
1791 | else { | |
1792 | lsm = TMP_VAR; | |
1793 | lsm_flag = true; | |
1794 | } | |
1795 | } | |
1796 | if (lsm_flag) <-- | |
1797 | MEM = lsm; <-- | |
1798 | */ | |
1799 | ||
1800 | static void | |
1801 | execute_sm_if_changed (edge ex, tree mem, tree tmp_var, tree flag) | |
1802 | { | |
1803 | basic_block new_bb, then_bb, old_dest; | |
1804 | bool loop_has_only_one_exit; | |
1805 | edge then_old_edge, orig_ex = ex; | |
1806 | gimple_stmt_iterator gsi; | |
1807 | gimple stmt; | |
1808 | struct prev_flag_edges *prev_edges = (struct prev_flag_edges *) ex->aux; | |
1809 | ||
1810 | /* ?? Insert store after previous store if applicable. See note | |
1811 | below. */ | |
1812 | if (prev_edges) | |
1813 | ex = prev_edges->append_cond_position; | |
1814 | ||
1815 | loop_has_only_one_exit = single_pred_p (ex->dest); | |
1816 | ||
1817 | if (loop_has_only_one_exit) | |
1818 | ex = split_block_after_labels (ex->dest); | |
1819 | ||
1820 | old_dest = ex->dest; | |
1821 | new_bb = split_edge (ex); | |
1822 | then_bb = create_empty_bb (new_bb); | |
1823 | if (current_loops && new_bb->loop_father) | |
1824 | add_bb_to_loop (then_bb, new_bb->loop_father); | |
1825 | ||
1826 | gsi = gsi_start_bb (new_bb); | |
1827 | stmt = gimple_build_cond (NE_EXPR, flag, boolean_false_node, | |
1828 | NULL_TREE, NULL_TREE); | |
1829 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1830 | ||
1831 | gsi = gsi_start_bb (then_bb); | |
1832 | /* Insert actual store. */ | |
1833 | stmt = gimple_build_assign (unshare_expr (mem), tmp_var); | |
1834 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1835 | ||
1836 | make_edge (new_bb, then_bb, EDGE_TRUE_VALUE); | |
1837 | make_edge (new_bb, old_dest, EDGE_FALSE_VALUE); | |
1838 | then_old_edge = make_edge (then_bb, old_dest, EDGE_FALLTHRU); | |
1839 | ||
1840 | set_immediate_dominator (CDI_DOMINATORS, then_bb, new_bb); | |
1841 | ||
1842 | if (prev_edges) | |
1843 | { | |
1844 | basic_block prevbb = prev_edges->last_cond_fallthru->src; | |
1845 | redirect_edge_succ (prev_edges->last_cond_fallthru, new_bb); | |
1846 | set_immediate_dominator (CDI_DOMINATORS, new_bb, prevbb); | |
1847 | set_immediate_dominator (CDI_DOMINATORS, old_dest, | |
1848 | recompute_dominator (CDI_DOMINATORS, old_dest)); | |
1849 | } | |
1850 | ||
1851 | /* ?? Because stores may alias, they must happen in the exact | |
1852 | sequence they originally happened. Save the position right after | |
1853 | the (_lsm) store we just created so we can continue appending after | |
1854 | it and maintain the original order. */ | |
1855 | { | |
1856 | struct prev_flag_edges *p; | |
1857 | ||
1858 | if (orig_ex->aux) | |
1859 | orig_ex->aux = NULL; | |
1860 | alloc_aux_for_edge (orig_ex, sizeof (struct prev_flag_edges)); | |
1861 | p = (struct prev_flag_edges *) orig_ex->aux; | |
1862 | p->append_cond_position = then_old_edge; | |
1863 | p->last_cond_fallthru = find_edge (new_bb, old_dest); | |
1864 | orig_ex->aux = (void *) p; | |
1865 | } | |
1866 | ||
1867 | if (!loop_has_only_one_exit) | |
1868 | for (gsi = gsi_start_phis (old_dest); !gsi_end_p (gsi); gsi_next (&gsi)) | |
1869 | { | |
1870 | gimple phi = gsi_stmt (gsi); | |
1871 | unsigned i; | |
1872 | ||
1873 | for (i = 0; i < gimple_phi_num_args (phi); i++) | |
1874 | if (gimple_phi_arg_edge (phi, i)->src == new_bb) | |
1875 | { | |
1876 | tree arg = gimple_phi_arg_def (phi, i); | |
60d535d2 | 1877 | add_phi_arg (phi, arg, then_old_edge, UNKNOWN_LOCATION); |
61025ec0 | 1878 | update_stmt (phi); |
1879 | } | |
1880 | } | |
1881 | /* Remove the original fall through edge. This was the | |
1882 | single_succ_edge (new_bb). */ | |
1883 | EDGE_SUCC (new_bb, 0)->flags &= ~EDGE_FALLTHRU; | |
1884 | } | |
1885 | ||
5c8a8be3 | 1886 | /* When REF is set on the location, set flag indicating the store. */ |
1887 | ||
1888 | struct sm_set_flag_if_changed | |
1889 | { | |
1890 | sm_set_flag_if_changed (tree flag_) : flag (flag_) {} | |
9af5ce0c | 1891 | bool operator () (mem_ref_loc_p loc); |
5c8a8be3 | 1892 | tree flag; |
1893 | }; | |
1894 | ||
1895 | bool | |
9af5ce0c | 1896 | sm_set_flag_if_changed::operator () (mem_ref_loc_p loc) |
5c8a8be3 | 1897 | { |
1898 | /* Only set the flag for writes. */ | |
1899 | if (is_gimple_assign (loc->stmt) | |
1900 | && gimple_assign_lhs_ptr (loc->stmt) == loc->ref) | |
1901 | { | |
1902 | gimple_stmt_iterator gsi = gsi_for_stmt (loc->stmt); | |
1903 | gimple stmt = gimple_build_assign (flag, boolean_true_node); | |
1904 | gsi_insert_after (&gsi, stmt, GSI_CONTINUE_LINKING); | |
1905 | } | |
1906 | return false; | |
1907 | } | |
1908 | ||
61025ec0 | 1909 | /* Helper function for execute_sm. On every location where REF is |
1910 | set, set an appropriate flag indicating the store. */ | |
1911 | ||
1912 | static tree | |
1913 | execute_sm_if_changed_flag_set (struct loop *loop, mem_ref_p ref) | |
1914 | { | |
61025ec0 | 1915 | tree flag; |
f86b328b | 1916 | char *str = get_lsm_tmp_name (ref->mem.ref, ~0, "_flag"); |
072f7ab1 | 1917 | flag = create_tmp_reg (boolean_type_node, str); |
5c8a8be3 | 1918 | for_all_locs_in_loop (loop, ref, sm_set_flag_if_changed (flag)); |
61025ec0 | 1919 | return flag; |
1920 | } | |
1921 | ||
063a8bce | 1922 | /* Executes store motion of memory reference REF from LOOP. |
749ea85f | 1923 | Exits from the LOOP are stored in EXITS. The initialization of the |
1924 | temporary variable is put to the preheader of the loop, and assignments | |
1925 | to the reference from the temporary variable are emitted to exits. */ | |
7d23383d | 1926 | |
1927 | static void | |
f1f41a6c | 1928 | execute_sm (struct loop *loop, vec<edge> exits, mem_ref_p ref) |
7d23383d | 1929 | { |
61025ec0 | 1930 | tree tmp_var, store_flag; |
7d23383d | 1931 | unsigned i; |
61025ec0 | 1932 | gimple load; |
99e96094 | 1933 | struct fmt_data fmt_data; |
bc9af2dd | 1934 | edge ex; |
75a70cf9 | 1935 | struct lim_aux_data *lim_data; |
61025ec0 | 1936 | bool multi_threaded_model_p = false; |
bc9af2dd | 1937 | gimple_stmt_iterator gsi; |
7d23383d | 1938 | |
69154f26 | 1939 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1940 | { | |
1941 | fprintf (dump_file, "Executing store motion of "); | |
09f4cf62 | 1942 | print_generic_expr (dump_file, ref->mem.ref, 0); |
69154f26 | 1943 | fprintf (dump_file, " from loop %d\n", loop->num); |
1944 | } | |
1945 | ||
09f4cf62 | 1946 | tmp_var = create_tmp_reg (TREE_TYPE (ref->mem.ref), |
1947 | get_lsm_tmp_name (ref->mem.ref, ~0)); | |
7d23383d | 1948 | |
99e96094 | 1949 | fmt_data.loop = loop; |
1950 | fmt_data.orig_loop = loop; | |
09f4cf62 | 1951 | for_each_index (&ref->mem.ref, force_move_till, &fmt_data); |
7d23383d | 1952 | |
c927329e | 1953 | if (bb_in_transaction (loop_preheader_edge (loop)->src) |
61025ec0 | 1954 | || !PARAM_VALUE (PARAM_ALLOW_STORE_DATA_RACES)) |
1955 | multi_threaded_model_p = true; | |
1956 | ||
1957 | if (multi_threaded_model_p) | |
1958 | store_flag = execute_sm_if_changed_flag_set (loop, ref); | |
1959 | ||
063a8bce | 1960 | rewrite_mem_refs (loop, ref, tmp_var); |
7d23383d | 1961 | |
bc9af2dd | 1962 | /* Emit the load code on a random exit edge or into the latch if |
1963 | the loop does not exit, so that we are sure it will be processed | |
1964 | by move_computations after all dependencies. */ | |
1965 | gsi = gsi_for_stmt (first_mem_ref_loc (loop, ref)->stmt); | |
61025ec0 | 1966 | |
1967 | /* FIXME/TODO: For the multi-threaded variant, we could avoid this | |
1968 | load altogether, since the store is predicated by a flag. We | |
1969 | could, do the load only if it was originally in the loop. */ | |
09f4cf62 | 1970 | load = gimple_build_assign (tmp_var, unshare_expr (ref->mem.ref)); |
75a70cf9 | 1971 | lim_data = init_lim_data (load); |
1972 | lim_data->max_loop = loop; | |
1973 | lim_data->tgt_loop = loop; | |
bc9af2dd | 1974 | gsi_insert_before (&gsi, load, GSI_SAME_STMT); |
7d23383d | 1975 | |
61025ec0 | 1976 | if (multi_threaded_model_p) |
7d23383d | 1977 | { |
61025ec0 | 1978 | load = gimple_build_assign (store_flag, boolean_false_node); |
1979 | lim_data = init_lim_data (load); | |
1980 | lim_data->max_loop = loop; | |
1981 | lim_data->tgt_loop = loop; | |
bc9af2dd | 1982 | gsi_insert_before (&gsi, load, GSI_SAME_STMT); |
7d23383d | 1983 | } |
61025ec0 | 1984 | |
1985 | /* Sink the store to every exit from the loop. */ | |
f1f41a6c | 1986 | FOR_EACH_VEC_ELT (exits, i, ex) |
61025ec0 | 1987 | if (!multi_threaded_model_p) |
1988 | { | |
1989 | gimple store; | |
09f4cf62 | 1990 | store = gimple_build_assign (unshare_expr (ref->mem.ref), tmp_var); |
61025ec0 | 1991 | gsi_insert_on_edge (ex, store); |
1992 | } | |
1993 | else | |
09f4cf62 | 1994 | execute_sm_if_changed (ex, ref->mem.ref, tmp_var, store_flag); |
7d23383d | 1995 | } |
1996 | ||
063a8bce | 1997 | /* Hoists memory references MEM_REFS out of LOOP. EXITS is the list of exit |
1998 | edges of the LOOP. */ | |
7d23383d | 1999 | |
2000 | static void | |
063a8bce | 2001 | hoist_memory_references (struct loop *loop, bitmap mem_refs, |
f1f41a6c | 2002 | vec<edge> exits) |
7d23383d | 2003 | { |
063a8bce | 2004 | mem_ref_p ref; |
2005 | unsigned i; | |
2006 | bitmap_iterator bi; | |
69154f26 | 2007 | |
063a8bce | 2008 | EXECUTE_IF_SET_IN_BITMAP (mem_refs, 0, i, bi) |
7d23383d | 2009 | { |
f1f41a6c | 2010 | ref = memory_accesses.refs_list[i]; |
063a8bce | 2011 | execute_sm (loop, exits, ref); |
7d23383d | 2012 | } |
55a03692 | 2013 | } |
2014 | ||
5c8a8be3 | 2015 | struct ref_always_accessed |
2016 | { | |
2017 | ref_always_accessed (struct loop *loop_, tree base_, bool stored_p_) | |
2018 | : loop (loop_), base (base_), stored_p (stored_p_) {} | |
9af5ce0c | 2019 | bool operator () (mem_ref_loc_p loc); |
5c8a8be3 | 2020 | struct loop *loop; |
2021 | tree base; | |
2022 | bool stored_p; | |
2023 | }; | |
7d23383d | 2024 | |
5c8a8be3 | 2025 | bool |
9af5ce0c | 2026 | ref_always_accessed::operator () (mem_ref_loc_p loc) |
7d23383d | 2027 | { |
063a8bce | 2028 | struct loop *must_exec; |
307f7fda | 2029 | |
5c8a8be3 | 2030 | if (!get_lim_data (loc->stmt)) |
2031 | return false; | |
7d23383d | 2032 | |
5c8a8be3 | 2033 | /* If we require an always executed store make sure the statement |
2034 | stores to the reference. */ | |
2035 | if (stored_p) | |
063a8bce | 2036 | { |
5c8a8be3 | 2037 | tree lhs; |
2038 | if (!gimple_get_lhs (loc->stmt)) | |
2039 | return false; | |
2040 | lhs = get_base_address (gimple_get_lhs (loc->stmt)); | |
2041 | if (!lhs) | |
2042 | return false; | |
2043 | if (INDIRECT_REF_P (lhs) | |
2044 | || TREE_CODE (lhs) == MEM_REF) | |
2045 | lhs = TREE_OPERAND (lhs, 0); | |
2046 | if (lhs != base) | |
2047 | return false; | |
2048 | } | |
7d23383d | 2049 | |
5c8a8be3 | 2050 | must_exec = get_lim_data (loc->stmt)->always_executed_in; |
2051 | if (!must_exec) | |
2052 | return false; | |
307f7fda | 2053 | |
5c8a8be3 | 2054 | if (must_exec == loop |
2055 | || flow_loop_nested_p (must_exec, loop)) | |
2056 | return true; | |
7d23383d | 2057 | |
5c8a8be3 | 2058 | return false; |
2059 | } | |
55a03692 | 2060 | |
5c8a8be3 | 2061 | /* Returns true if REF is always accessed in LOOP. If STORED_P is true |
2062 | make sure REF is always stored to in LOOP. */ | |
2063 | ||
2064 | static bool | |
2065 | ref_always_accessed_p (struct loop *loop, mem_ref_p ref, bool stored_p) | |
2066 | { | |
2067 | tree base = ao_ref_base (&ref->mem); | |
2068 | if (TREE_CODE (base) == MEM_REF) | |
2069 | base = TREE_OPERAND (base, 0); | |
2070 | ||
2071 | return for_all_locs_in_loop (loop, ref, | |
2072 | ref_always_accessed (loop, base, stored_p)); | |
55a03692 | 2073 | } |
2074 | ||
063a8bce | 2075 | /* Returns true if REF1 and REF2 are independent. */ |
55a03692 | 2076 | |
063a8bce | 2077 | static bool |
2078 | refs_independent_p (mem_ref_p ref1, mem_ref_p ref2) | |
55a03692 | 2079 | { |
09f4cf62 | 2080 | if (ref1 == ref2) |
063a8bce | 2081 | return true; |
09f4cf62 | 2082 | |
063a8bce | 2083 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2084 | fprintf (dump_file, "Querying dependency of refs %u and %u: ", | |
2085 | ref1->id, ref2->id); | |
2086 | ||
09f4cf62 | 2087 | if (mem_refs_may_alias_p (ref1, ref2, &memory_accesses.ttae_cache)) |
063a8bce | 2088 | { |
063a8bce | 2089 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2090 | fprintf (dump_file, "dependent.\n"); | |
2091 | return false; | |
2092 | } | |
2093 | else | |
2094 | { | |
063a8bce | 2095 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2096 | fprintf (dump_file, "independent.\n"); | |
2097 | return true; | |
2098 | } | |
55a03692 | 2099 | } |
2100 | ||
8f9829e8 | 2101 | /* Mark REF dependent on stores or loads (according to STORED_P) in LOOP |
2102 | and its super-loops. */ | |
55a03692 | 2103 | |
2104 | static void | |
8f9829e8 | 2105 | record_dep_loop (struct loop *loop, mem_ref_p ref, bool stored_p) |
55a03692 | 2106 | { |
8f9829e8 | 2107 | /* We can propagate dependent-in-loop bits up the loop |
2108 | hierarchy to all outer loops. */ | |
2109 | while (loop != current_loops->tree_root | |
feba4360 | 2110 | && bitmap_set_bit (&ref->dep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
8f9829e8 | 2111 | loop = loop_outer (loop); |
063a8bce | 2112 | } |
55a03692 | 2113 | |
063a8bce | 2114 | /* Returns true if REF is independent on all other memory references in |
2115 | LOOP. */ | |
55a03692 | 2116 | |
063a8bce | 2117 | static bool |
8f9829e8 | 2118 | ref_indep_loop_p_1 (struct loop *loop, mem_ref_p ref, bool stored_p) |
063a8bce | 2119 | { |
0766b2c0 | 2120 | bitmap refs_to_check; |
063a8bce | 2121 | unsigned i; |
2122 | bitmap_iterator bi; | |
063a8bce | 2123 | mem_ref_p aref; |
2124 | ||
8f9829e8 | 2125 | if (stored_p) |
feba4360 | 2126 | refs_to_check = &memory_accesses.refs_in_loop[loop->num]; |
0766b2c0 | 2127 | else |
feba4360 | 2128 | refs_to_check = &memory_accesses.refs_stored_in_loop[loop->num]; |
55a03692 | 2129 | |
04911505 | 2130 | if (bitmap_bit_p (refs_to_check, UNANALYZABLE_MEM_ID)) |
2131 | return false; | |
2132 | ||
063a8bce | 2133 | EXECUTE_IF_SET_IN_BITMAP (refs_to_check, 0, i, bi) |
55a03692 | 2134 | { |
f1f41a6c | 2135 | aref = memory_accesses.refs_list[i]; |
04911505 | 2136 | if (!refs_independent_p (ref, aref)) |
8f9829e8 | 2137 | return false; |
55a03692 | 2138 | } |
55a03692 | 2139 | |
8f9829e8 | 2140 | return true; |
55a03692 | 2141 | } |
2142 | ||
063a8bce | 2143 | /* Returns true if REF is independent on all other memory references in |
2144 | LOOP. Wrapper over ref_indep_loop_p_1, caching its results. */ | |
55a03692 | 2145 | |
063a8bce | 2146 | static bool |
8f9829e8 | 2147 | ref_indep_loop_p_2 (struct loop *loop, mem_ref_p ref, bool stored_p) |
55a03692 | 2148 | { |
feba4360 | 2149 | stored_p |= bitmap_bit_p (&ref->stored, loop->num); |
04911505 | 2150 | |
feba4360 | 2151 | if (bitmap_bit_p (&ref->indep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
063a8bce | 2152 | return true; |
feba4360 | 2153 | if (bitmap_bit_p (&ref->dep_loop, LOOP_DEP_BIT (loop->num, stored_p))) |
063a8bce | 2154 | return false; |
55a03692 | 2155 | |
8f9829e8 | 2156 | struct loop *inner = loop->inner; |
2157 | while (inner) | |
2158 | { | |
2159 | if (!ref_indep_loop_p_2 (inner, ref, stored_p)) | |
2160 | return false; | |
2161 | inner = inner->next; | |
2162 | } | |
2163 | ||
2164 | bool indep_p = ref_indep_loop_p_1 (loop, ref, stored_p); | |
342ea212 | 2165 | |
063a8bce | 2166 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2167 | fprintf (dump_file, "Querying dependencies of ref %u in loop %d: %s\n", | |
8f9829e8 | 2168 | ref->id, loop->num, indep_p ? "independent" : "dependent"); |
063a8bce | 2169 | |
8f9829e8 | 2170 | /* Record the computed result in the cache. */ |
2171 | if (indep_p) | |
2172 | { | |
feba4360 | 2173 | if (bitmap_set_bit (&ref->indep_loop, LOOP_DEP_BIT (loop->num, stored_p)) |
8f9829e8 | 2174 | && stored_p) |
2175 | { | |
2176 | /* If it's independend against all refs then it's independent | |
2177 | against stores, too. */ | |
feba4360 | 2178 | bitmap_set_bit (&ref->indep_loop, LOOP_DEP_BIT (loop->num, false)); |
8f9829e8 | 2179 | } |
2180 | } | |
2181 | else | |
2182 | { | |
2183 | record_dep_loop (loop, ref, stored_p); | |
2184 | if (!stored_p) | |
2185 | { | |
2186 | /* If it's dependent against stores it's dependent against | |
2187 | all refs, too. */ | |
2188 | record_dep_loop (loop, ref, true); | |
2189 | } | |
2190 | } | |
063a8bce | 2191 | |
8f9829e8 | 2192 | return indep_p; |
2193 | } | |
2194 | ||
2195 | /* Returns true if REF is independent on all other memory references in | |
2196 | LOOP. */ | |
2197 | ||
2198 | static bool | |
2199 | ref_indep_loop_p (struct loop *loop, mem_ref_p ref) | |
2200 | { | |
2201 | gcc_checking_assert (MEM_ANALYZABLE (ref)); | |
2202 | ||
2203 | return ref_indep_loop_p_2 (loop, ref, false); | |
55a03692 | 2204 | } |
2205 | ||
063a8bce | 2206 | /* Returns true if we can perform store motion of REF from LOOP. */ |
55a03692 | 2207 | |
063a8bce | 2208 | static bool |
2209 | can_sm_ref_p (struct loop *loop, mem_ref_p ref) | |
55a03692 | 2210 | { |
307f7fda | 2211 | tree base; |
2212 | ||
0766b2c0 | 2213 | /* Can't hoist unanalyzable refs. */ |
2214 | if (!MEM_ANALYZABLE (ref)) | |
2215 | return false; | |
2216 | ||
063a8bce | 2217 | /* It should be movable. */ |
09f4cf62 | 2218 | if (!is_gimple_reg_type (TREE_TYPE (ref->mem.ref)) |
2219 | || TREE_THIS_VOLATILE (ref->mem.ref) | |
2220 | || !for_each_index (&ref->mem.ref, may_move_till, loop)) | |
063a8bce | 2221 | return false; |
342ea212 | 2222 | |
16d9b5d8 | 2223 | /* If it can throw fail, we do not properly update EH info. */ |
09f4cf62 | 2224 | if (tree_could_throw_p (ref->mem.ref)) |
16d9b5d8 | 2225 | return false; |
2226 | ||
307f7fda | 2227 | /* If it can trap, it must be always executed in LOOP. |
2228 | Readonly memory locations may trap when storing to them, but | |
2229 | tree_could_trap_p is a predicate for rvalues, so check that | |
2230 | explicitly. */ | |
09f4cf62 | 2231 | base = get_base_address (ref->mem.ref); |
2232 | if ((tree_could_trap_p (ref->mem.ref) | |
307f7fda | 2233 | || (DECL_P (base) && TREE_READONLY (base))) |
2234 | && !ref_always_accessed_p (loop, ref, true)) | |
063a8bce | 2235 | return false; |
342ea212 | 2236 | |
063a8bce | 2237 | /* And it must be independent on all other memory references |
2238 | in LOOP. */ | |
2239 | if (!ref_indep_loop_p (loop, ref)) | |
2240 | return false; | |
342ea212 | 2241 | |
063a8bce | 2242 | return true; |
342ea212 | 2243 | } |
2244 | ||
063a8bce | 2245 | /* Marks the references in LOOP for that store motion should be performed |
2246 | in REFS_TO_SM. SM_EXECUTED is the set of references for that store | |
2247 | motion was performed in one of the outer loops. */ | |
342ea212 | 2248 | |
2249 | static void | |
063a8bce | 2250 | find_refs_for_sm (struct loop *loop, bitmap sm_executed, bitmap refs_to_sm) |
55a03692 | 2251 | { |
feba4360 | 2252 | bitmap refs = &memory_accesses.all_refs_stored_in_loop[loop->num]; |
063a8bce | 2253 | unsigned i; |
2254 | bitmap_iterator bi; | |
2255 | mem_ref_p ref; | |
2256 | ||
2257 | EXECUTE_IF_AND_COMPL_IN_BITMAP (refs, sm_executed, 0, i, bi) | |
2258 | { | |
f1f41a6c | 2259 | ref = memory_accesses.refs_list[i]; |
063a8bce | 2260 | if (can_sm_ref_p (loop, ref)) |
2261 | bitmap_set_bit (refs_to_sm, i); | |
2262 | } | |
342ea212 | 2263 | } |
55a03692 | 2264 | |
063a8bce | 2265 | /* Checks whether LOOP (with exits stored in EXITS array) is suitable |
2266 | for a store motion optimization (i.e. whether we can insert statement | |
2267 | on its exits). */ | |
342ea212 | 2268 | |
063a8bce | 2269 | static bool |
2270 | loop_suitable_for_sm (struct loop *loop ATTRIBUTE_UNUSED, | |
f1f41a6c | 2271 | vec<edge> exits) |
342ea212 | 2272 | { |
063a8bce | 2273 | unsigned i; |
2274 | edge ex; | |
55a03692 | 2275 | |
f1f41a6c | 2276 | FOR_EACH_VEC_ELT (exits, i, ex) |
9102193b | 2277 | if (ex->flags & (EDGE_ABNORMAL | EDGE_EH)) |
063a8bce | 2278 | return false; |
2279 | ||
2280 | return true; | |
55a03692 | 2281 | } |
2282 | ||
7d23383d | 2283 | /* Try to perform store motion for all memory references modified inside |
063a8bce | 2284 | LOOP. SM_EXECUTED is the bitmap of the memory references for that |
2285 | store motion was executed in one of the outer loops. */ | |
7d23383d | 2286 | |
2287 | static void | |
063a8bce | 2288 | store_motion_loop (struct loop *loop, bitmap sm_executed) |
7d23383d | 2289 | { |
f1f41a6c | 2290 | vec<edge> exits = get_loop_exit_edges (loop); |
063a8bce | 2291 | struct loop *subloop; |
39f8afdf | 2292 | bitmap sm_in_loop = BITMAP_ALLOC (&lim_bitmap_obstack); |
7d23383d | 2293 | |
063a8bce | 2294 | if (loop_suitable_for_sm (loop, exits)) |
7d23383d | 2295 | { |
063a8bce | 2296 | find_refs_for_sm (loop, sm_executed, sm_in_loop); |
2297 | hoist_memory_references (loop, sm_in_loop, exits); | |
7d23383d | 2298 | } |
f1f41a6c | 2299 | exits.release (); |
063a8bce | 2300 | |
2301 | bitmap_ior_into (sm_executed, sm_in_loop); | |
2302 | for (subloop = loop->inner; subloop != NULL; subloop = subloop->next) | |
2303 | store_motion_loop (subloop, sm_executed); | |
2304 | bitmap_and_compl_into (sm_executed, sm_in_loop); | |
2305 | BITMAP_FREE (sm_in_loop); | |
7d23383d | 2306 | } |
2307 | ||
2308 | /* Try to perform store motion for all memory references modified inside | |
7194de72 | 2309 | loops. */ |
7d23383d | 2310 | |
2311 | static void | |
063a8bce | 2312 | store_motion (void) |
7d23383d | 2313 | { |
2314 | struct loop *loop; | |
39f8afdf | 2315 | bitmap sm_executed = BITMAP_ALLOC (&lim_bitmap_obstack); |
dda28f7c | 2316 | |
063a8bce | 2317 | for (loop = current_loops->tree_root->inner; loop != NULL; loop = loop->next) |
2318 | store_motion_loop (loop, sm_executed); | |
17519ba0 | 2319 | |
063a8bce | 2320 | BITMAP_FREE (sm_executed); |
75a70cf9 | 2321 | gsi_commit_edge_inserts (); |
7d23383d | 2322 | } |
2323 | ||
2324 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks of LOOP, i.e. | |
2325 | for each such basic block bb records the outermost loop for that execution | |
2326 | of its header implies execution of bb. CONTAINS_CALL is the bitmap of | |
2327 | blocks that contain a nonpure call. */ | |
2328 | ||
2329 | static void | |
feba4360 | 2330 | fill_always_executed_in_1 (struct loop *loop, sbitmap contains_call) |
7d23383d | 2331 | { |
2332 | basic_block bb = NULL, *bbs, last = NULL; | |
2333 | unsigned i; | |
2334 | edge e; | |
2335 | struct loop *inn_loop = loop; | |
2336 | ||
2fd20c29 | 2337 | if (ALWAYS_EXECUTED_IN (loop->header) == NULL) |
7d23383d | 2338 | { |
2339 | bbs = get_loop_body_in_dom_order (loop); | |
2340 | ||
2341 | for (i = 0; i < loop->num_nodes; i++) | |
2342 | { | |
cd665a06 | 2343 | edge_iterator ei; |
7d23383d | 2344 | bb = bbs[i]; |
2345 | ||
2346 | if (dominated_by_p (CDI_DOMINATORS, loop->latch, bb)) | |
2347 | last = bb; | |
2348 | ||
08b7917c | 2349 | if (bitmap_bit_p (contains_call, bb->index)) |
7d23383d | 2350 | break; |
2351 | ||
cd665a06 | 2352 | FOR_EACH_EDGE (e, ei, bb->succs) |
7d23383d | 2353 | if (!flow_bb_inside_loop_p (loop, e->dest)) |
2354 | break; | |
2355 | if (e) | |
2356 | break; | |
2357 | ||
2358 | /* A loop might be infinite (TODO use simple loop analysis | |
2359 | to disprove this if possible). */ | |
2360 | if (bb->flags & BB_IRREDUCIBLE_LOOP) | |
2361 | break; | |
2362 | ||
2363 | if (!flow_bb_inside_loop_p (inn_loop, bb)) | |
2364 | break; | |
2365 | ||
2366 | if (bb->loop_father->header == bb) | |
2367 | { | |
2368 | if (!dominated_by_p (CDI_DOMINATORS, loop->latch, bb)) | |
2369 | break; | |
2370 | ||
2371 | /* In a loop that is always entered we may proceed anyway. | |
2372 | But record that we entered it and stop once we leave it. */ | |
2373 | inn_loop = bb->loop_father; | |
2374 | } | |
2375 | } | |
2376 | ||
2377 | while (1) | |
2378 | { | |
2fd20c29 | 2379 | SET_ALWAYS_EXECUTED_IN (last, loop); |
7d23383d | 2380 | if (last == loop->header) |
2381 | break; | |
2382 | last = get_immediate_dominator (CDI_DOMINATORS, last); | |
2383 | } | |
2384 | ||
2385 | free (bbs); | |
2386 | } | |
2387 | ||
2388 | for (loop = loop->inner; loop; loop = loop->next) | |
feba4360 | 2389 | fill_always_executed_in_1 (loop, contains_call); |
7d23383d | 2390 | } |
2391 | ||
feba4360 | 2392 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks, i.e. |
2393 | for each such basic block bb records the outermost loop for that execution | |
2394 | of its header implies execution of bb. */ | |
7d23383d | 2395 | |
2396 | static void | |
feba4360 | 2397 | fill_always_executed_in (void) |
7d23383d | 2398 | { |
2399 | sbitmap contains_call = sbitmap_alloc (last_basic_block); | |
7d23383d | 2400 | basic_block bb; |
feba4360 | 2401 | struct loop *loop; |
4fb07d00 | 2402 | |
53c5d9d4 | 2403 | bitmap_clear (contains_call); |
7d23383d | 2404 | FOR_EACH_BB (bb) |
2405 | { | |
feba4360 | 2406 | gimple_stmt_iterator gsi; |
2407 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) | |
7d23383d | 2408 | { |
feba4360 | 2409 | if (nonpure_call_p (gsi_stmt (gsi))) |
7d23383d | 2410 | break; |
2411 | } | |
2412 | ||
feba4360 | 2413 | if (!gsi_end_p (gsi)) |
08b7917c | 2414 | bitmap_set_bit (contains_call, bb->index); |
7d23383d | 2415 | } |
2416 | ||
7194de72 | 2417 | for (loop = current_loops->tree_root->inner; loop; loop = loop->next) |
feba4360 | 2418 | fill_always_executed_in_1 (loop, contains_call); |
7d23383d | 2419 | |
2420 | sbitmap_free (contains_call); | |
feba4360 | 2421 | } |
2422 | ||
2423 | ||
2424 | /* Compute the global information needed by the loop invariant motion pass. */ | |
75a70cf9 | 2425 | |
feba4360 | 2426 | static void |
2427 | tree_ssa_lim_initialize (void) | |
2428 | { | |
2429 | unsigned i; | |
2430 | ||
2431 | bitmap_obstack_initialize (&lim_bitmap_obstack); | |
75a70cf9 | 2432 | lim_aux_data_map = pointer_map_create (); |
de60f90c | 2433 | |
2434 | if (flag_tm) | |
2435 | compute_transaction_bits (); | |
61025ec0 | 2436 | |
2437 | alloc_aux_for_edges (0); | |
feba4360 | 2438 | |
3e871d4d | 2439 | memory_accesses.refs.create (100); |
feba4360 | 2440 | memory_accesses.refs_list.create (100); |
2441 | /* Allocate a special, unanalyzable mem-ref with ID zero. */ | |
2442 | memory_accesses.refs_list.quick_push | |
2443 | (mem_ref_alloc (error_mark_node, 0, UNANALYZABLE_MEM_ID)); | |
2444 | ||
41f75a99 | 2445 | memory_accesses.refs_in_loop.create (number_of_loops (cfun)); |
2446 | memory_accesses.refs_in_loop.quick_grow (number_of_loops (cfun)); | |
2447 | memory_accesses.refs_stored_in_loop.create (number_of_loops (cfun)); | |
2448 | memory_accesses.refs_stored_in_loop.quick_grow (number_of_loops (cfun)); | |
2449 | memory_accesses.all_refs_stored_in_loop.create (number_of_loops (cfun)); | |
2450 | memory_accesses.all_refs_stored_in_loop.quick_grow (number_of_loops (cfun)); | |
feba4360 | 2451 | |
41f75a99 | 2452 | for (i = 0; i < number_of_loops (cfun); i++) |
feba4360 | 2453 | { |
2454 | bitmap_initialize (&memory_accesses.refs_in_loop[i], | |
2455 | &lim_bitmap_obstack); | |
2456 | bitmap_initialize (&memory_accesses.refs_stored_in_loop[i], | |
2457 | &lim_bitmap_obstack); | |
2458 | bitmap_initialize (&memory_accesses.all_refs_stored_in_loop[i], | |
2459 | &lim_bitmap_obstack); | |
2460 | } | |
2461 | ||
2462 | memory_accesses.ttae_cache = NULL; | |
7d23383d | 2463 | } |
2464 | ||
2465 | /* Cleans up after the invariant motion pass. */ | |
2466 | ||
2467 | static void | |
2468 | tree_ssa_lim_finalize (void) | |
2469 | { | |
2470 | basic_block bb; | |
063a8bce | 2471 | unsigned i; |
83b709f2 | 2472 | mem_ref_p ref; |
7d23383d | 2473 | |
61025ec0 | 2474 | free_aux_for_edges (); |
2475 | ||
7d23383d | 2476 | FOR_EACH_BB (bb) |
2fd20c29 | 2477 | SET_ALWAYS_EXECUTED_IN (bb, NULL); |
063a8bce | 2478 | |
4fb07d00 | 2479 | bitmap_obstack_release (&lim_bitmap_obstack); |
75a70cf9 | 2480 | pointer_map_destroy (lim_aux_data_map); |
2481 | ||
3e871d4d | 2482 | memory_accesses.refs.dispose (); |
063a8bce | 2483 | |
f1f41a6c | 2484 | FOR_EACH_VEC_ELT (memory_accesses.refs_list, i, ref) |
83b709f2 | 2485 | memref_free (ref); |
f1f41a6c | 2486 | memory_accesses.refs_list.release (); |
83b709f2 | 2487 | |
f1f41a6c | 2488 | memory_accesses.refs_in_loop.release (); |
8f9829e8 | 2489 | memory_accesses.refs_stored_in_loop.release (); |
f1f41a6c | 2490 | memory_accesses.all_refs_stored_in_loop.release (); |
063a8bce | 2491 | |
2492 | if (memory_accesses.ttae_cache) | |
78d53e33 | 2493 | free_affine_expand_cache (&memory_accesses.ttae_cache); |
7d23383d | 2494 | } |
2495 | ||
7194de72 | 2496 | /* Moves invariants from loops. Only "expensive" invariants are moved out -- |
7d23383d | 2497 | i.e. those that are likely to be win regardless of the register pressure. */ |
2498 | ||
9bf0a3f9 | 2499 | unsigned int |
7194de72 | 2500 | tree_ssa_lim (void) |
7d23383d | 2501 | { |
9bf0a3f9 | 2502 | unsigned int todo; |
2503 | ||
7194de72 | 2504 | tree_ssa_lim_initialize (); |
7d23383d | 2505 | |
063a8bce | 2506 | /* Gathers information about memory accesses in the loops. */ |
2507 | analyze_memory_references (); | |
2508 | ||
feba4360 | 2509 | /* Fills ALWAYS_EXECUTED_IN information for basic blocks. */ |
2510 | fill_always_executed_in (); | |
2511 | ||
7d23383d | 2512 | /* For each statement determine the outermost loop in that it is |
2513 | invariant and cost for computing the invariant. */ | |
54c91640 | 2514 | invariantness_dom_walker (CDI_DOMINATORS) |
2515 | .walk (cfun->cfg->x_entry_block_ptr); | |
7d23383d | 2516 | |
063a8bce | 2517 | /* Execute store motion. Force the necessary invariants to be moved |
2518 | out of the loops as well. */ | |
2519 | store_motion (); | |
7d23383d | 2520 | |
2521 | /* Move the expressions that are expensive enough. */ | |
9bf0a3f9 | 2522 | todo = move_computations (); |
7d23383d | 2523 | |
2524 | tree_ssa_lim_finalize (); | |
9bf0a3f9 | 2525 | |
2526 | return todo; | |
7d23383d | 2527 | } |
f86b328b | 2528 | |
2529 | /* Loop invariant motion pass. */ | |
2530 | ||
2531 | static unsigned int | |
2532 | tree_ssa_loop_im (void) | |
2533 | { | |
2534 | if (number_of_loops (cfun) <= 1) | |
2535 | return 0; | |
2536 | ||
2537 | return tree_ssa_lim (); | |
2538 | } | |
2539 | ||
2540 | static bool | |
2541 | gate_tree_ssa_loop_im (void) | |
2542 | { | |
2543 | return flag_tree_loop_im != 0; | |
2544 | } | |
2545 | ||
2546 | namespace { | |
2547 | ||
2548 | const pass_data pass_data_lim = | |
2549 | { | |
2550 | GIMPLE_PASS, /* type */ | |
2551 | "lim", /* name */ | |
2552 | OPTGROUP_LOOP, /* optinfo_flags */ | |
2553 | true, /* has_gate */ | |
2554 | true, /* has_execute */ | |
2555 | TV_LIM, /* tv_id */ | |
2556 | PROP_cfg, /* properties_required */ | |
2557 | 0, /* properties_provided */ | |
2558 | 0, /* properties_destroyed */ | |
2559 | 0, /* todo_flags_start */ | |
2560 | 0, /* todo_flags_finish */ | |
2561 | }; | |
2562 | ||
2563 | class pass_lim : public gimple_opt_pass | |
2564 | { | |
2565 | public: | |
2566 | pass_lim (gcc::context *ctxt) | |
2567 | : gimple_opt_pass (pass_data_lim, ctxt) | |
2568 | {} | |
2569 | ||
2570 | /* opt_pass methods: */ | |
2571 | opt_pass * clone () { return new pass_lim (m_ctxt); } | |
2572 | bool gate () { return gate_tree_ssa_loop_im (); } | |
2573 | unsigned int execute () { return tree_ssa_loop_im (); } | |
2574 | ||
2575 | }; // class pass_lim | |
2576 | ||
2577 | } // anon namespace | |
2578 | ||
2579 | gimple_opt_pass * | |
2580 | make_pass_lim (gcc::context *ctxt) | |
2581 | { | |
2582 | return new pass_lim (ctxt); | |
2583 | } | |
2584 | ||
2585 |