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dec41e98 | 1 | /* Induction variable optimizations. |
0ac758f7 | 2 | Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009 |
3 | Free Software Foundation, Inc. | |
dec41e98 | 4 | |
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify it | |
8 | under the terms of the GNU General Public License as published by the | |
8c4c00c1 | 9 | Free Software Foundation; either version 3, or (at your option) any |
dec41e98 | 10 | later version. |
11 | ||
12 | GCC is distributed in the hope that it will be useful, but WITHOUT | |
13 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
8c4c00c1 | 18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
dec41e98 | 20 | |
21 | /* This pass tries to find the optimal set of induction variables for the loop. | |
22 | It optimizes just the basic linear induction variables (although adding | |
23 | support for other types should not be too hard). It includes the | |
24 | optimizations commonly known as strength reduction, induction variable | |
25 | coalescing and induction variable elimination. It does it in the | |
26 | following steps: | |
27 | ||
28 | 1) The interesting uses of induction variables are found. This includes | |
29 | ||
30 | -- uses of induction variables in non-linear expressions | |
31 | -- addresses of arrays | |
32 | -- comparisons of induction variables | |
33 | ||
34 | 2) Candidates for the induction variables are found. This includes | |
35 | ||
36 | -- old induction variables | |
37 | -- the variables defined by expressions derived from the "interesting | |
38 | uses" above | |
39 | ||
40 | 3) The optimal (w.r. to a cost function) set of variables is chosen. The | |
41 | cost function assigns a cost to sets of induction variables and consists | |
42 | of three parts: | |
43 | ||
44 | -- The use costs. Each of the interesting uses chooses the best induction | |
45 | variable in the set and adds its cost to the sum. The cost reflects | |
46 | the time spent on modifying the induction variables value to be usable | |
47 | for the given purpose (adding base and offset for arrays, etc.). | |
48 | -- The variable costs. Each of the variables has a cost assigned that | |
49 | reflects the costs associated with incrementing the value of the | |
50 | variable. The original variables are somewhat preferred. | |
51 | -- The set cost. Depending on the size of the set, extra cost may be | |
52 | added to reflect register pressure. | |
53 | ||
54 | All the costs are defined in a machine-specific way, using the target | |
55 | hooks and machine descriptions to determine them. | |
56 | ||
57 | 4) The trees are transformed to use the new variables, the dead code is | |
58 | removed. | |
59 | ||
60 | All of this is done loop by loop. Doing it globally is theoretically | |
61 | possible, it might give a better performance and it might enable us | |
62 | to decide costs more precisely, but getting all the interactions right | |
63 | would be complicated. */ | |
64 | ||
65 | #include "config.h" | |
66 | #include "system.h" | |
67 | #include "coretypes.h" | |
68 | #include "tm.h" | |
69 | #include "tree.h" | |
70 | #include "rtl.h" | |
71 | #include "tm_p.h" | |
72 | #include "hard-reg-set.h" | |
73 | #include "basic-block.h" | |
74 | #include "output.h" | |
75 | #include "diagnostic.h" | |
76 | #include "tree-flow.h" | |
77 | #include "tree-dump.h" | |
78 | #include "timevar.h" | |
79 | #include "cfgloop.h" | |
80 | #include "varray.h" | |
81 | #include "expr.h" | |
82 | #include "tree-pass.h" | |
83 | #include "ggc.h" | |
84 | #include "insn-config.h" | |
85 | #include "recog.h" | |
b30a8715 | 86 | #include "pointer-set.h" |
dec41e98 | 87 | #include "hashtab.h" |
88 | #include "tree-chrec.h" | |
89 | #include "tree-scalar-evolution.h" | |
90 | #include "cfgloop.h" | |
91 | #include "params.h" | |
3fd8a7ab | 92 | #include "langhooks.h" |
d3610bea | 93 | #include "tree-affine.h" |
7e995af7 | 94 | #include "target.h" |
dec41e98 | 95 | |
96 | /* The infinite cost. */ | |
97 | #define INFTY 10000000 | |
98 | ||
99 | /* The expected number of loop iterations. TODO -- use profiling instead of | |
100 | this. */ | |
101 | #define AVG_LOOP_NITER(LOOP) 5 | |
102 | ||
dec41e98 | 103 | |
104 | /* Representation of the induction variable. */ | |
105 | struct iv | |
106 | { | |
107 | tree base; /* Initial value of the iv. */ | |
065d134e | 108 | tree base_object; /* A memory object to that the induction variable points. */ |
dec41e98 | 109 | tree step; /* Step of the iv (constant only). */ |
110 | tree ssa_name; /* The ssa name with the value. */ | |
111 | bool biv_p; /* Is it a biv? */ | |
112 | bool have_use_for; /* Do we already have a use for it? */ | |
113 | unsigned use_id; /* The identifier in the use if it is the case. */ | |
114 | }; | |
115 | ||
116 | /* Per-ssa version information (induction variable descriptions, etc.). */ | |
117 | struct version_info | |
118 | { | |
119 | tree name; /* The ssa name. */ | |
120 | struct iv *iv; /* Induction variable description. */ | |
121 | bool has_nonlin_use; /* For a loop-level invariant, whether it is used in | |
122 | an expression that is not an induction variable. */ | |
123 | unsigned inv_id; /* Id of an invariant. */ | |
124 | bool preserve_biv; /* For the original biv, whether to preserve it. */ | |
125 | }; | |
126 | ||
dec41e98 | 127 | /* Types of uses. */ |
128 | enum use_type | |
129 | { | |
130 | USE_NONLINEAR_EXPR, /* Use in a nonlinear expression. */ | |
dec41e98 | 131 | USE_ADDRESS, /* Use in an address. */ |
132 | USE_COMPARE /* Use is a compare. */ | |
133 | }; | |
134 | ||
3c2818b0 | 135 | /* Cost of a computation. */ |
136 | typedef struct | |
137 | { | |
138 | unsigned cost; /* The runtime cost. */ | |
139 | unsigned complexity; /* The estimate of the complexity of the code for | |
140 | the computation (in no concrete units -- | |
141 | complexity field should be larger for more | |
142 | complex expressions and addressing modes). */ | |
143 | } comp_cost; | |
144 | ||
145 | static const comp_cost zero_cost = {0, 0}; | |
146 | static const comp_cost infinite_cost = {INFTY, INFTY}; | |
147 | ||
dec41e98 | 148 | /* The candidate - cost pair. */ |
149 | struct cost_pair | |
150 | { | |
151 | struct iv_cand *cand; /* The candidate. */ | |
3c2818b0 | 152 | comp_cost cost; /* The cost. */ |
dec41e98 | 153 | bitmap depends_on; /* The list of invariants that have to be |
154 | preserved. */ | |
c4d3b428 | 155 | tree value; /* For final value elimination, the expression for |
156 | the final value of the iv. For iv elimination, | |
157 | the new bound to compare with. */ | |
dec41e98 | 158 | }; |
159 | ||
160 | /* Use. */ | |
161 | struct iv_use | |
162 | { | |
163 | unsigned id; /* The id of the use. */ | |
164 | enum use_type type; /* Type of the use. */ | |
165 | struct iv *iv; /* The induction variable it is based on. */ | |
75a70cf9 | 166 | gimple stmt; /* Statement in that it occurs. */ |
dec41e98 | 167 | tree *op_p; /* The place where it occurs. */ |
00991688 | 168 | bitmap related_cands; /* The set of "related" iv candidates, plus the common |
169 | important ones. */ | |
dec41e98 | 170 | |
171 | unsigned n_map_members; /* Number of candidates in the cost_map list. */ | |
172 | struct cost_pair *cost_map; | |
173 | /* The costs wrto the iv candidates. */ | |
174 | ||
175 | struct iv_cand *selected; | |
176 | /* The selected candidate. */ | |
177 | }; | |
178 | ||
179 | /* The position where the iv is computed. */ | |
180 | enum iv_position | |
181 | { | |
182 | IP_NORMAL, /* At the end, just before the exit condition. */ | |
183 | IP_END, /* At the end of the latch block. */ | |
184 | IP_ORIGINAL /* The original biv. */ | |
185 | }; | |
186 | ||
187 | /* The induction variable candidate. */ | |
188 | struct iv_cand | |
189 | { | |
190 | unsigned id; /* The number of the candidate. */ | |
191 | bool important; /* Whether this is an "important" candidate, i.e. such | |
192 | that it should be considered by all uses. */ | |
193 | enum iv_position pos; /* Where it is computed. */ | |
75a70cf9 | 194 | gimple incremented_at;/* For original biv, the statement where it is |
dec41e98 | 195 | incremented. */ |
196 | tree var_before; /* The variable used for it before increment. */ | |
197 | tree var_after; /* The variable used for it after increment. */ | |
198 | struct iv *iv; /* The value of the candidate. NULL for | |
199 | "pseudocandidate" used to indicate the possibility | |
200 | to replace the final value of an iv by direct | |
201 | computation of the value. */ | |
202 | unsigned cost; /* Cost of the candidate. */ | |
651874e1 | 203 | bitmap depends_on; /* The list of invariants that are used in step of the |
204 | biv. */ | |
dec41e98 | 205 | }; |
206 | ||
207 | /* The data used by the induction variable optimizations. */ | |
208 | ||
7d18ea07 | 209 | typedef struct iv_use *iv_use_p; |
210 | DEF_VEC_P(iv_use_p); | |
211 | DEF_VEC_ALLOC_P(iv_use_p,heap); | |
212 | ||
213 | typedef struct iv_cand *iv_cand_p; | |
214 | DEF_VEC_P(iv_cand_p); | |
215 | DEF_VEC_ALLOC_P(iv_cand_p,heap); | |
216 | ||
dec41e98 | 217 | struct ivopts_data |
218 | { | |
219 | /* The currently optimized loop. */ | |
220 | struct loop *current_loop; | |
221 | ||
0ac758f7 | 222 | /* Numbers of iterations for all exits of the current loop. */ |
223 | struct pointer_map_t *niters; | |
f529eb25 | 224 | |
fe382241 | 225 | /* Number of registers used in it. */ |
226 | unsigned regs_used; | |
227 | ||
dec41e98 | 228 | /* The size of version_info array allocated. */ |
229 | unsigned version_info_size; | |
230 | ||
231 | /* The array of information for the ssa names. */ | |
232 | struct version_info *version_info; | |
233 | ||
234 | /* The bitmap of indices in version_info whose value was changed. */ | |
235 | bitmap relevant; | |
236 | ||
dec41e98 | 237 | /* The uses of induction variables. */ |
7d18ea07 | 238 | VEC(iv_use_p,heap) *iv_uses; |
dec41e98 | 239 | |
240 | /* The candidates. */ | |
7d18ea07 | 241 | VEC(iv_cand_p,heap) *iv_candidates; |
dec41e98 | 242 | |
0a501ca6 | 243 | /* A bitmap of important candidates. */ |
244 | bitmap important_candidates; | |
245 | ||
0ac758f7 | 246 | /* The maximum invariant id. */ |
247 | unsigned max_inv_id; | |
248 | ||
dec41e98 | 249 | /* Whether to consider just related and important candidates when replacing a |
250 | use. */ | |
251 | bool consider_all_candidates; | |
0ac758f7 | 252 | |
253 | /* Are we optimizing for speed? */ | |
254 | bool speed; | |
dec41e98 | 255 | }; |
256 | ||
00991688 | 257 | /* An assignment of iv candidates to uses. */ |
258 | ||
259 | struct iv_ca | |
260 | { | |
261 | /* The number of uses covered by the assignment. */ | |
262 | unsigned upto; | |
263 | ||
264 | /* Number of uses that cannot be expressed by the candidates in the set. */ | |
265 | unsigned bad_uses; | |
266 | ||
267 | /* Candidate assigned to a use, together with the related costs. */ | |
268 | struct cost_pair **cand_for_use; | |
269 | ||
270 | /* Number of times each candidate is used. */ | |
271 | unsigned *n_cand_uses; | |
272 | ||
273 | /* The candidates used. */ | |
274 | bitmap cands; | |
275 | ||
13ea2c1f | 276 | /* The number of candidates in the set. */ |
277 | unsigned n_cands; | |
278 | ||
00991688 | 279 | /* Total number of registers needed. */ |
280 | unsigned n_regs; | |
281 | ||
282 | /* Total cost of expressing uses. */ | |
3c2818b0 | 283 | comp_cost cand_use_cost; |
00991688 | 284 | |
285 | /* Total cost of candidates. */ | |
286 | unsigned cand_cost; | |
287 | ||
288 | /* Number of times each invariant is used. */ | |
289 | unsigned *n_invariant_uses; | |
290 | ||
291 | /* Total cost of the assignment. */ | |
3c2818b0 | 292 | comp_cost cost; |
00991688 | 293 | }; |
294 | ||
295 | /* Difference of two iv candidate assignments. */ | |
296 | ||
297 | struct iv_ca_delta | |
298 | { | |
299 | /* Changed use. */ | |
300 | struct iv_use *use; | |
301 | ||
302 | /* An old assignment (for rollback purposes). */ | |
303 | struct cost_pair *old_cp; | |
304 | ||
305 | /* A new assignment. */ | |
306 | struct cost_pair *new_cp; | |
307 | ||
308 | /* Next change in the list. */ | |
309 | struct iv_ca_delta *next_change; | |
310 | }; | |
311 | ||
dec41e98 | 312 | /* Bound on number of candidates below that all candidates are considered. */ |
313 | ||
314 | #define CONSIDER_ALL_CANDIDATES_BOUND \ | |
315 | ((unsigned) PARAM_VALUE (PARAM_IV_CONSIDER_ALL_CANDIDATES_BOUND)) | |
316 | ||
91275768 | 317 | /* If there are more iv occurrences, we just give up (it is quite unlikely that |
dec41e98 | 318 | optimizing such a loop would help, and it would take ages). */ |
319 | ||
320 | #define MAX_CONSIDERED_USES \ | |
321 | ((unsigned) PARAM_VALUE (PARAM_IV_MAX_CONSIDERED_USES)) | |
322 | ||
13ea2c1f | 323 | /* If there are at most this number of ivs in the set, try removing unnecessary |
324 | ivs from the set always. */ | |
325 | ||
326 | #define ALWAYS_PRUNE_CAND_SET_BOUND \ | |
327 | ((unsigned) PARAM_VALUE (PARAM_IV_ALWAYS_PRUNE_CAND_SET_BOUND)) | |
328 | ||
dec41e98 | 329 | /* The list of trees for that the decl_rtl field must be reset is stored |
330 | here. */ | |
331 | ||
7d18ea07 | 332 | static VEC(tree,heap) *decl_rtl_to_reset; |
dec41e98 | 333 | |
334 | /* Number of uses recorded in DATA. */ | |
335 | ||
336 | static inline unsigned | |
337 | n_iv_uses (struct ivopts_data *data) | |
338 | { | |
7d18ea07 | 339 | return VEC_length (iv_use_p, data->iv_uses); |
dec41e98 | 340 | } |
341 | ||
342 | /* Ith use recorded in DATA. */ | |
343 | ||
344 | static inline struct iv_use * | |
345 | iv_use (struct ivopts_data *data, unsigned i) | |
346 | { | |
7d18ea07 | 347 | return VEC_index (iv_use_p, data->iv_uses, i); |
dec41e98 | 348 | } |
349 | ||
350 | /* Number of candidates recorded in DATA. */ | |
351 | ||
352 | static inline unsigned | |
353 | n_iv_cands (struct ivopts_data *data) | |
354 | { | |
7d18ea07 | 355 | return VEC_length (iv_cand_p, data->iv_candidates); |
dec41e98 | 356 | } |
357 | ||
358 | /* Ith candidate recorded in DATA. */ | |
359 | ||
360 | static inline struct iv_cand * | |
361 | iv_cand (struct ivopts_data *data, unsigned i) | |
362 | { | |
7d18ea07 | 363 | return VEC_index (iv_cand_p, data->iv_candidates, i); |
dec41e98 | 364 | } |
365 | ||
dec41e98 | 366 | /* The single loop exit if it dominates the latch, NULL otherwise. */ |
367 | ||
8feba661 | 368 | edge |
dec41e98 | 369 | single_dom_exit (struct loop *loop) |
370 | { | |
d9e7e1a2 | 371 | edge exit = single_exit (loop); |
dec41e98 | 372 | |
373 | if (!exit) | |
374 | return NULL; | |
375 | ||
376 | if (!just_once_each_iteration_p (loop, exit->src)) | |
377 | return NULL; | |
378 | ||
379 | return exit; | |
380 | } | |
381 | ||
382 | /* Dumps information about the induction variable IV to FILE. */ | |
383 | ||
384 | extern void dump_iv (FILE *, struct iv *); | |
385 | void | |
386 | dump_iv (FILE *file, struct iv *iv) | |
387 | { | |
065d134e | 388 | if (iv->ssa_name) |
389 | { | |
390 | fprintf (file, "ssa name "); | |
391 | print_generic_expr (file, iv->ssa_name, TDF_SLIM); | |
392 | fprintf (file, "\n"); | |
393 | } | |
dec41e98 | 394 | |
dbc64c75 | 395 | fprintf (file, " type "); |
396 | print_generic_expr (file, TREE_TYPE (iv->base), TDF_SLIM); | |
397 | fprintf (file, "\n"); | |
398 | ||
dec41e98 | 399 | if (iv->step) |
400 | { | |
401 | fprintf (file, " base "); | |
402 | print_generic_expr (file, iv->base, TDF_SLIM); | |
403 | fprintf (file, "\n"); | |
404 | ||
405 | fprintf (file, " step "); | |
406 | print_generic_expr (file, iv->step, TDF_SLIM); | |
407 | fprintf (file, "\n"); | |
408 | } | |
409 | else | |
410 | { | |
411 | fprintf (file, " invariant "); | |
412 | print_generic_expr (file, iv->base, TDF_SLIM); | |
413 | fprintf (file, "\n"); | |
414 | } | |
415 | ||
065d134e | 416 | if (iv->base_object) |
417 | { | |
418 | fprintf (file, " base object "); | |
419 | print_generic_expr (file, iv->base_object, TDF_SLIM); | |
420 | fprintf (file, "\n"); | |
421 | } | |
422 | ||
dec41e98 | 423 | if (iv->biv_p) |
424 | fprintf (file, " is a biv\n"); | |
425 | } | |
426 | ||
427 | /* Dumps information about the USE to FILE. */ | |
428 | ||
429 | extern void dump_use (FILE *, struct iv_use *); | |
430 | void | |
431 | dump_use (FILE *file, struct iv_use *use) | |
432 | { | |
dec41e98 | 433 | fprintf (file, "use %d\n", use->id); |
434 | ||
435 | switch (use->type) | |
436 | { | |
437 | case USE_NONLINEAR_EXPR: | |
438 | fprintf (file, " generic\n"); | |
439 | break; | |
440 | ||
dec41e98 | 441 | case USE_ADDRESS: |
442 | fprintf (file, " address\n"); | |
443 | break; | |
444 | ||
445 | case USE_COMPARE: | |
446 | fprintf (file, " compare\n"); | |
447 | break; | |
448 | ||
449 | default: | |
8c0963c4 | 450 | gcc_unreachable (); |
dec41e98 | 451 | } |
452 | ||
dbc64c75 | 453 | fprintf (file, " in statement "); |
75a70cf9 | 454 | print_gimple_stmt (file, use->stmt, 0, 0); |
dbc64c75 | 455 | fprintf (file, "\n"); |
456 | ||
457 | fprintf (file, " at position "); | |
458 | if (use->op_p) | |
459 | print_generic_expr (file, *use->op_p, TDF_SLIM); | |
460 | fprintf (file, "\n"); | |
461 | ||
065d134e | 462 | dump_iv (file, use->iv); |
dbc64c75 | 463 | |
d4caf099 | 464 | if (use->related_cands) |
465 | { | |
466 | fprintf (file, " related candidates "); | |
467 | dump_bitmap (file, use->related_cands); | |
468 | } | |
dec41e98 | 469 | } |
470 | ||
471 | /* Dumps information about the uses to FILE. */ | |
472 | ||
473 | extern void dump_uses (FILE *, struct ivopts_data *); | |
474 | void | |
475 | dump_uses (FILE *file, struct ivopts_data *data) | |
476 | { | |
477 | unsigned i; | |
478 | struct iv_use *use; | |
479 | ||
480 | for (i = 0; i < n_iv_uses (data); i++) | |
481 | { | |
482 | use = iv_use (data, i); | |
483 | ||
484 | dump_use (file, use); | |
485 | fprintf (file, "\n"); | |
486 | } | |
487 | } | |
488 | ||
489 | /* Dumps information about induction variable candidate CAND to FILE. */ | |
490 | ||
491 | extern void dump_cand (FILE *, struct iv_cand *); | |
492 | void | |
493 | dump_cand (FILE *file, struct iv_cand *cand) | |
494 | { | |
495 | struct iv *iv = cand->iv; | |
496 | ||
497 | fprintf (file, "candidate %d%s\n", | |
498 | cand->id, cand->important ? " (important)" : ""); | |
499 | ||
651874e1 | 500 | if (cand->depends_on) |
501 | { | |
502 | fprintf (file, " depends on "); | |
503 | dump_bitmap (file, cand->depends_on); | |
504 | } | |
505 | ||
dec41e98 | 506 | if (!iv) |
507 | { | |
508 | fprintf (file, " final value replacement\n"); | |
509 | return; | |
510 | } | |
511 | ||
512 | switch (cand->pos) | |
513 | { | |
514 | case IP_NORMAL: | |
515 | fprintf (file, " incremented before exit test\n"); | |
516 | break; | |
517 | ||
518 | case IP_END: | |
519 | fprintf (file, " incremented at end\n"); | |
520 | break; | |
521 | ||
522 | case IP_ORIGINAL: | |
523 | fprintf (file, " original biv\n"); | |
524 | break; | |
525 | } | |
526 | ||
065d134e | 527 | dump_iv (file, iv); |
dec41e98 | 528 | } |
529 | ||
530 | /* Returns the info for ssa version VER. */ | |
531 | ||
532 | static inline struct version_info * | |
533 | ver_info (struct ivopts_data *data, unsigned ver) | |
534 | { | |
535 | return data->version_info + ver; | |
536 | } | |
537 | ||
538 | /* Returns the info for ssa name NAME. */ | |
539 | ||
540 | static inline struct version_info * | |
541 | name_info (struct ivopts_data *data, tree name) | |
542 | { | |
543 | return ver_info (data, SSA_NAME_VERSION (name)); | |
544 | } | |
545 | ||
dec41e98 | 546 | /* Returns true if STMT is after the place where the IP_NORMAL ivs will be |
547 | emitted in LOOP. */ | |
548 | ||
549 | static bool | |
75a70cf9 | 550 | stmt_after_ip_normal_pos (struct loop *loop, gimple stmt) |
dec41e98 | 551 | { |
75a70cf9 | 552 | basic_block bb = ip_normal_pos (loop), sbb = gimple_bb (stmt); |
dec41e98 | 553 | |
8c0963c4 | 554 | gcc_assert (bb); |
dec41e98 | 555 | |
556 | if (sbb == loop->latch) | |
557 | return true; | |
558 | ||
559 | if (sbb != bb) | |
560 | return false; | |
561 | ||
562 | return stmt == last_stmt (bb); | |
563 | } | |
564 | ||
565 | /* Returns true if STMT if after the place where the original induction | |
566 | variable CAND is incremented. */ | |
567 | ||
568 | static bool | |
75a70cf9 | 569 | stmt_after_ip_original_pos (struct iv_cand *cand, gimple stmt) |
dec41e98 | 570 | { |
75a70cf9 | 571 | basic_block cand_bb = gimple_bb (cand->incremented_at); |
572 | basic_block stmt_bb = gimple_bb (stmt); | |
573 | gimple_stmt_iterator bsi; | |
dec41e98 | 574 | |
575 | if (!dominated_by_p (CDI_DOMINATORS, stmt_bb, cand_bb)) | |
576 | return false; | |
577 | ||
578 | if (stmt_bb != cand_bb) | |
579 | return true; | |
580 | ||
581 | /* Scan the block from the end, since the original ivs are usually | |
582 | incremented at the end of the loop body. */ | |
75a70cf9 | 583 | for (bsi = gsi_last_bb (stmt_bb); ; gsi_prev (&bsi)) |
dec41e98 | 584 | { |
75a70cf9 | 585 | if (gsi_stmt (bsi) == cand->incremented_at) |
dec41e98 | 586 | return false; |
75a70cf9 | 587 | if (gsi_stmt (bsi) == stmt) |
dec41e98 | 588 | return true; |
589 | } | |
590 | } | |
591 | ||
592 | /* Returns true if STMT if after the place where the induction variable | |
593 | CAND is incremented in LOOP. */ | |
594 | ||
595 | static bool | |
75a70cf9 | 596 | stmt_after_increment (struct loop *loop, struct iv_cand *cand, gimple stmt) |
dec41e98 | 597 | { |
598 | switch (cand->pos) | |
599 | { | |
600 | case IP_END: | |
601 | return false; | |
602 | ||
603 | case IP_NORMAL: | |
604 | return stmt_after_ip_normal_pos (loop, stmt); | |
605 | ||
606 | case IP_ORIGINAL: | |
607 | return stmt_after_ip_original_pos (cand, stmt); | |
608 | ||
609 | default: | |
8c0963c4 | 610 | gcc_unreachable (); |
dec41e98 | 611 | } |
612 | } | |
613 | ||
dcd24d3c | 614 | /* Returns true if EXP is a ssa name that occurs in an abnormal phi node. */ |
615 | ||
616 | static bool | |
617 | abnormal_ssa_name_p (tree exp) | |
618 | { | |
619 | if (!exp) | |
620 | return false; | |
621 | ||
622 | if (TREE_CODE (exp) != SSA_NAME) | |
623 | return false; | |
624 | ||
625 | return SSA_NAME_OCCURS_IN_ABNORMAL_PHI (exp) != 0; | |
626 | } | |
627 | ||
628 | /* Returns false if BASE or INDEX contains a ssa name that occurs in an | |
629 | abnormal phi node. Callback for for_each_index. */ | |
630 | ||
631 | static bool | |
632 | idx_contains_abnormal_ssa_name_p (tree base, tree *index, | |
633 | void *data ATTRIBUTE_UNUSED) | |
634 | { | |
5e19919e | 635 | if (TREE_CODE (base) == ARRAY_REF || TREE_CODE (base) == ARRAY_RANGE_REF) |
dcd24d3c | 636 | { |
637 | if (abnormal_ssa_name_p (TREE_OPERAND (base, 2))) | |
638 | return false; | |
639 | if (abnormal_ssa_name_p (TREE_OPERAND (base, 3))) | |
640 | return false; | |
641 | } | |
642 | ||
643 | return !abnormal_ssa_name_p (*index); | |
644 | } | |
645 | ||
646 | /* Returns true if EXPR contains a ssa name that occurs in an | |
647 | abnormal phi node. */ | |
648 | ||
72079d62 | 649 | bool |
dcd24d3c | 650 | contains_abnormal_ssa_name_p (tree expr) |
651 | { | |
652 | enum tree_code code; | |
f0d6e81c | 653 | enum tree_code_class codeclass; |
dcd24d3c | 654 | |
655 | if (!expr) | |
656 | return false; | |
657 | ||
658 | code = TREE_CODE (expr); | |
f0d6e81c | 659 | codeclass = TREE_CODE_CLASS (code); |
dcd24d3c | 660 | |
661 | if (code == SSA_NAME) | |
662 | return SSA_NAME_OCCURS_IN_ABNORMAL_PHI (expr) != 0; | |
663 | ||
664 | if (code == INTEGER_CST | |
665 | || is_gimple_min_invariant (expr)) | |
666 | return false; | |
667 | ||
668 | if (code == ADDR_EXPR) | |
669 | return !for_each_index (&TREE_OPERAND (expr, 0), | |
670 | idx_contains_abnormal_ssa_name_p, | |
671 | NULL); | |
672 | ||
f0d6e81c | 673 | switch (codeclass) |
dcd24d3c | 674 | { |
675 | case tcc_binary: | |
676 | case tcc_comparison: | |
677 | if (contains_abnormal_ssa_name_p (TREE_OPERAND (expr, 1))) | |
678 | return true; | |
679 | ||
680 | /* Fallthru. */ | |
681 | case tcc_unary: | |
682 | if (contains_abnormal_ssa_name_p (TREE_OPERAND (expr, 0))) | |
683 | return true; | |
684 | ||
685 | break; | |
686 | ||
687 | default: | |
688 | gcc_unreachable (); | |
689 | } | |
690 | ||
691 | return false; | |
692 | } | |
693 | ||
dcd24d3c | 694 | /* Returns tree describing number of iterations determined from |
b091dc59 | 695 | EXIT of DATA->current_loop, or NULL if something goes wrong. */ |
696 | ||
dcd24d3c | 697 | static tree |
b091dc59 | 698 | niter_for_exit (struct ivopts_data *data, edge exit) |
699 | { | |
dcd24d3c | 700 | struct tree_niter_desc desc; |
b30a8715 | 701 | tree niter; |
702 | void **slot; | |
b091dc59 | 703 | |
b30a8715 | 704 | if (!data->niters) |
b091dc59 | 705 | { |
b30a8715 | 706 | data->niters = pointer_map_create (); |
707 | slot = NULL; | |
708 | } | |
709 | else | |
710 | slot = pointer_map_contains (data->niters, exit); | |
dcd24d3c | 711 | |
b30a8715 | 712 | if (!slot) |
713 | { | |
dcd24d3c | 714 | /* Try to determine number of iterations. We must know it |
715 | unconditionally (i.e., without possibility of # of iterations | |
716 | being zero). Also, we cannot safely work with ssa names that | |
717 | appear in phi nodes on abnormal edges, so that we do not create | |
718 | overlapping life ranges for them (PR 27283). */ | |
719 | if (number_of_iterations_exit (data->current_loop, | |
720 | exit, &desc, true) | |
cd743a11 | 721 | && integer_zerop (desc.may_be_zero) |
dcd24d3c | 722 | && !contains_abnormal_ssa_name_p (desc.niter)) |
b30a8715 | 723 | niter = desc.niter; |
dcd24d3c | 724 | else |
b30a8715 | 725 | niter = NULL_TREE; |
726 | ||
727 | *pointer_map_insert (data->niters, exit) = niter; | |
b091dc59 | 728 | } |
729 | else | |
f0d6e81c | 730 | niter = (tree) *slot; |
b091dc59 | 731 | |
b30a8715 | 732 | return niter; |
b091dc59 | 733 | } |
734 | ||
dcd24d3c | 735 | /* Returns tree describing number of iterations determined from |
b091dc59 | 736 | single dominating exit of DATA->current_loop, or NULL if something |
737 | goes wrong. */ | |
738 | ||
dcd24d3c | 739 | static tree |
b091dc59 | 740 | niter_for_single_dom_exit (struct ivopts_data *data) |
741 | { | |
742 | edge exit = single_dom_exit (data->current_loop); | |
743 | ||
744 | if (!exit) | |
745 | return NULL; | |
746 | ||
747 | return niter_for_exit (data, exit); | |
748 | } | |
749 | ||
dec41e98 | 750 | /* Initializes data structures used by the iv optimization pass, stored |
fe382241 | 751 | in DATA. */ |
dec41e98 | 752 | |
753 | static void | |
fe382241 | 754 | tree_ssa_iv_optimize_init (struct ivopts_data *data) |
dec41e98 | 755 | { |
dec41e98 | 756 | data->version_info_size = 2 * num_ssa_names; |
4c36ffe6 | 757 | data->version_info = XCNEWVEC (struct version_info, data->version_info_size); |
27335ffd | 758 | data->relevant = BITMAP_ALLOC (NULL); |
759 | data->important_candidates = BITMAP_ALLOC (NULL); | |
dec41e98 | 760 | data->max_inv_id = 0; |
b30a8715 | 761 | data->niters = NULL; |
7d18ea07 | 762 | data->iv_uses = VEC_alloc (iv_use_p, heap, 20); |
763 | data->iv_candidates = VEC_alloc (iv_cand_p, heap, 20); | |
764 | decl_rtl_to_reset = VEC_alloc (tree, heap, 20); | |
dec41e98 | 765 | } |
766 | ||
065d134e | 767 | /* Returns a memory object to that EXPR points. In case we are able to |
768 | determine that it does not point to any such object, NULL is returned. */ | |
769 | ||
770 | static tree | |
771 | determine_base_object (tree expr) | |
772 | { | |
773 | enum tree_code code = TREE_CODE (expr); | |
0de36bdb | 774 | tree base, obj; |
065d134e | 775 | |
9b6564b5 | 776 | /* If this is a pointer casted to any type, we need to determine |
777 | the base object for the pointer; so handle conversions before | |
778 | throwing away non-pointer expressions. */ | |
72dd6141 | 779 | if (CONVERT_EXPR_P (expr)) |
9b6564b5 | 780 | return determine_base_object (TREE_OPERAND (expr, 0)); |
781 | ||
065d134e | 782 | if (!POINTER_TYPE_P (TREE_TYPE (expr))) |
783 | return NULL_TREE; | |
784 | ||
785 | switch (code) | |
786 | { | |
787 | case INTEGER_CST: | |
788 | return NULL_TREE; | |
789 | ||
790 | case ADDR_EXPR: | |
791 | obj = TREE_OPERAND (expr, 0); | |
792 | base = get_base_address (obj); | |
793 | ||
794 | if (!base) | |
390955a6 | 795 | return expr; |
065d134e | 796 | |
eb91f88e | 797 | if (TREE_CODE (base) == INDIRECT_REF) |
390955a6 | 798 | return determine_base_object (TREE_OPERAND (base, 0)); |
eb91f88e | 799 | |
538577e2 | 800 | return fold_convert (ptr_type_node, |
801 | build_fold_addr_expr (base)); | |
065d134e | 802 | |
0de36bdb | 803 | case POINTER_PLUS_EXPR: |
804 | return determine_base_object (TREE_OPERAND (expr, 0)); | |
805 | ||
065d134e | 806 | case PLUS_EXPR: |
807 | case MINUS_EXPR: | |
0de36bdb | 808 | /* Pointer addition is done solely using POINTER_PLUS_EXPR. */ |
809 | gcc_unreachable (); | |
065d134e | 810 | |
811 | default: | |
812 | return fold_convert (ptr_type_node, expr); | |
813 | } | |
814 | } | |
815 | ||
dec41e98 | 816 | /* Allocates an induction variable with given initial value BASE and step STEP |
817 | for loop LOOP. */ | |
818 | ||
819 | static struct iv * | |
820 | alloc_iv (tree base, tree step) | |
821 | { | |
4c36ffe6 | 822 | struct iv *iv = XCNEW (struct iv); |
7a973feb | 823 | gcc_assert (step != NULL_TREE); |
dec41e98 | 824 | |
825 | iv->base = base; | |
065d134e | 826 | iv->base_object = determine_base_object (base); |
dec41e98 | 827 | iv->step = step; |
828 | iv->biv_p = false; | |
829 | iv->have_use_for = false; | |
830 | iv->use_id = 0; | |
831 | iv->ssa_name = NULL_TREE; | |
832 | ||
833 | return iv; | |
834 | } | |
835 | ||
836 | /* Sets STEP and BASE for induction variable IV. */ | |
837 | ||
838 | static void | |
839 | set_iv (struct ivopts_data *data, tree iv, tree base, tree step) | |
840 | { | |
841 | struct version_info *info = name_info (data, iv); | |
842 | ||
8c0963c4 | 843 | gcc_assert (!info->iv); |
dec41e98 | 844 | |
845 | bitmap_set_bit (data->relevant, SSA_NAME_VERSION (iv)); | |
846 | info->iv = alloc_iv (base, step); | |
847 | info->iv->ssa_name = iv; | |
848 | } | |
849 | ||
850 | /* Finds induction variable declaration for VAR. */ | |
851 | ||
852 | static struct iv * | |
853 | get_iv (struct ivopts_data *data, tree var) | |
854 | { | |
855 | basic_block bb; | |
7a973feb | 856 | tree type = TREE_TYPE (var); |
857 | ||
858 | if (!POINTER_TYPE_P (type) | |
859 | && !INTEGRAL_TYPE_P (type)) | |
860 | return NULL; | |
861 | ||
dec41e98 | 862 | if (!name_info (data, var)->iv) |
863 | { | |
75a70cf9 | 864 | bb = gimple_bb (SSA_NAME_DEF_STMT (var)); |
dec41e98 | 865 | |
866 | if (!bb | |
867 | || !flow_bb_inside_loop_p (data->current_loop, bb)) | |
7a973feb | 868 | set_iv (data, var, var, build_int_cst (type, 0)); |
dec41e98 | 869 | } |
870 | ||
871 | return name_info (data, var)->iv; | |
872 | } | |
873 | ||
651874e1 | 874 | /* Determines the step of a biv defined in PHI. Returns NULL if PHI does |
875 | not define a simple affine biv with nonzero step. */ | |
dec41e98 | 876 | |
877 | static tree | |
75a70cf9 | 878 | determine_biv_step (gimple phi) |
dec41e98 | 879 | { |
75a70cf9 | 880 | struct loop *loop = gimple_bb (phi)->loop_father; |
553b9523 | 881 | tree name = PHI_RESULT (phi); |
882 | affine_iv iv; | |
dec41e98 | 883 | |
884 | if (!is_gimple_reg (name)) | |
885 | return NULL_TREE; | |
886 | ||
76610704 | 887 | if (!simple_iv (loop, loop, name, &iv, true)) |
dec41e98 | 888 | return NULL_TREE; |
889 | ||
7a973feb | 890 | return integer_zerop (iv.step) ? NULL_TREE : iv.step; |
dec41e98 | 891 | } |
892 | ||
dec41e98 | 893 | /* Finds basic ivs. */ |
894 | ||
895 | static bool | |
896 | find_bivs (struct ivopts_data *data) | |
897 | { | |
75a70cf9 | 898 | gimple phi; |
899 | tree step, type, base; | |
dec41e98 | 900 | bool found = false; |
901 | struct loop *loop = data->current_loop; | |
75a70cf9 | 902 | gimple_stmt_iterator psi; |
dec41e98 | 903 | |
75a70cf9 | 904 | for (psi = gsi_start_phis (loop->header); !gsi_end_p (psi); gsi_next (&psi)) |
dec41e98 | 905 | { |
75a70cf9 | 906 | phi = gsi_stmt (psi); |
907 | ||
dec41e98 | 908 | if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (PHI_RESULT (phi))) |
909 | continue; | |
910 | ||
911 | step = determine_biv_step (phi); | |
dec41e98 | 912 | if (!step) |
913 | continue; | |
dec41e98 | 914 | |
915 | base = PHI_ARG_DEF_FROM_EDGE (phi, loop_preheader_edge (loop)); | |
b9845e76 | 916 | base = expand_simple_operations (base); |
651874e1 | 917 | if (contains_abnormal_ssa_name_p (base) |
918 | || contains_abnormal_ssa_name_p (step)) | |
dec41e98 | 919 | continue; |
920 | ||
921 | type = TREE_TYPE (PHI_RESULT (phi)); | |
922 | base = fold_convert (type, base); | |
651874e1 | 923 | if (step) |
06240723 | 924 | { |
925 | if (POINTER_TYPE_P (type)) | |
926 | step = fold_convert (sizetype, step); | |
927 | else | |
928 | step = fold_convert (type, step); | |
929 | } | |
dec41e98 | 930 | |
931 | set_iv (data, PHI_RESULT (phi), base, step); | |
932 | found = true; | |
933 | } | |
934 | ||
935 | return found; | |
936 | } | |
937 | ||
938 | /* Marks basic ivs. */ | |
939 | ||
940 | static void | |
941 | mark_bivs (struct ivopts_data *data) | |
942 | { | |
75a70cf9 | 943 | gimple phi; |
944 | tree var; | |
dec41e98 | 945 | struct iv *iv, *incr_iv; |
946 | struct loop *loop = data->current_loop; | |
947 | basic_block incr_bb; | |
75a70cf9 | 948 | gimple_stmt_iterator psi; |
dec41e98 | 949 | |
75a70cf9 | 950 | for (psi = gsi_start_phis (loop->header); !gsi_end_p (psi); gsi_next (&psi)) |
dec41e98 | 951 | { |
75a70cf9 | 952 | phi = gsi_stmt (psi); |
953 | ||
dec41e98 | 954 | iv = get_iv (data, PHI_RESULT (phi)); |
955 | if (!iv) | |
956 | continue; | |
957 | ||
958 | var = PHI_ARG_DEF_FROM_EDGE (phi, loop_latch_edge (loop)); | |
959 | incr_iv = get_iv (data, var); | |
960 | if (!incr_iv) | |
961 | continue; | |
962 | ||
963 | /* If the increment is in the subloop, ignore it. */ | |
75a70cf9 | 964 | incr_bb = gimple_bb (SSA_NAME_DEF_STMT (var)); |
dec41e98 | 965 | if (incr_bb->loop_father != data->current_loop |
966 | || (incr_bb->flags & BB_IRREDUCIBLE_LOOP)) | |
967 | continue; | |
968 | ||
969 | iv->biv_p = true; | |
970 | incr_iv->biv_p = true; | |
971 | } | |
972 | } | |
973 | ||
974 | /* Checks whether STMT defines a linear induction variable and stores its | |
553b9523 | 975 | parameters to IV. */ |
dec41e98 | 976 | |
977 | static bool | |
75a70cf9 | 978 | find_givs_in_stmt_scev (struct ivopts_data *data, gimple stmt, affine_iv *iv) |
dec41e98 | 979 | { |
980 | tree lhs; | |
981 | struct loop *loop = data->current_loop; | |
982 | ||
553b9523 | 983 | iv->base = NULL_TREE; |
984 | iv->step = NULL_TREE; | |
dec41e98 | 985 | |
75a70cf9 | 986 | if (gimple_code (stmt) != GIMPLE_ASSIGN) |
dec41e98 | 987 | return false; |
988 | ||
75a70cf9 | 989 | lhs = gimple_assign_lhs (stmt); |
dec41e98 | 990 | if (TREE_CODE (lhs) != SSA_NAME) |
991 | return false; | |
992 | ||
76610704 | 993 | if (!simple_iv (loop, loop_containing_stmt (stmt), lhs, iv, true)) |
dec41e98 | 994 | return false; |
553b9523 | 995 | iv->base = expand_simple_operations (iv->base); |
dec41e98 | 996 | |
553b9523 | 997 | if (contains_abnormal_ssa_name_p (iv->base) |
998 | || contains_abnormal_ssa_name_p (iv->step)) | |
dec41e98 | 999 | return false; |
1000 | ||
1001 | return true; | |
1002 | } | |
1003 | ||
1004 | /* Finds general ivs in statement STMT. */ | |
1005 | ||
1006 | static void | |
75a70cf9 | 1007 | find_givs_in_stmt (struct ivopts_data *data, gimple stmt) |
dec41e98 | 1008 | { |
553b9523 | 1009 | affine_iv iv; |
dec41e98 | 1010 | |
553b9523 | 1011 | if (!find_givs_in_stmt_scev (data, stmt, &iv)) |
dec41e98 | 1012 | return; |
1013 | ||
75a70cf9 | 1014 | set_iv (data, gimple_assign_lhs (stmt), iv.base, iv.step); |
dec41e98 | 1015 | } |
1016 | ||
1017 | /* Finds general ivs in basic block BB. */ | |
1018 | ||
1019 | static void | |
1020 | find_givs_in_bb (struct ivopts_data *data, basic_block bb) | |
1021 | { | |
75a70cf9 | 1022 | gimple_stmt_iterator bsi; |
dec41e98 | 1023 | |
75a70cf9 | 1024 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
1025 | find_givs_in_stmt (data, gsi_stmt (bsi)); | |
dec41e98 | 1026 | } |
1027 | ||
1028 | /* Finds general ivs. */ | |
1029 | ||
1030 | static void | |
1031 | find_givs (struct ivopts_data *data) | |
1032 | { | |
1033 | struct loop *loop = data->current_loop; | |
1034 | basic_block *body = get_loop_body_in_dom_order (loop); | |
1035 | unsigned i; | |
1036 | ||
1037 | for (i = 0; i < loop->num_nodes; i++) | |
1038 | find_givs_in_bb (data, body[i]); | |
1039 | free (body); | |
1040 | } | |
1041 | ||
dec41e98 | 1042 | /* For each ssa name defined in LOOP determines whether it is an induction |
1043 | variable and if so, its initial value and step. */ | |
1044 | ||
1045 | static bool | |
1046 | find_induction_variables (struct ivopts_data *data) | |
1047 | { | |
1048 | unsigned i; | |
0cc4271a | 1049 | bitmap_iterator bi; |
dec41e98 | 1050 | |
1051 | if (!find_bivs (data)) | |
1052 | return false; | |
1053 | ||
1054 | find_givs (data); | |
1055 | mark_bivs (data); | |
dec41e98 | 1056 | |
1057 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1058 | { | |
dcd24d3c | 1059 | tree niter = niter_for_single_dom_exit (data); |
b091dc59 | 1060 | |
1061 | if (niter) | |
dec41e98 | 1062 | { |
1063 | fprintf (dump_file, " number of iterations "); | |
dcd24d3c | 1064 | print_generic_expr (dump_file, niter, TDF_SLIM); |
1065 | fprintf (dump_file, "\n\n"); | |
dec41e98 | 1066 | }; |
1067 | ||
1068 | fprintf (dump_file, "Induction variables:\n\n"); | |
1069 | ||
0cc4271a | 1070 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
dec41e98 | 1071 | { |
1072 | if (ver_info (data, i)->iv) | |
1073 | dump_iv (dump_file, ver_info (data, i)->iv); | |
0cc4271a | 1074 | } |
dec41e98 | 1075 | } |
1076 | ||
1077 | return true; | |
1078 | } | |
1079 | ||
1080 | /* Records a use of type USE_TYPE at *USE_P in STMT whose value is IV. */ | |
1081 | ||
1082 | static struct iv_use * | |
1083 | record_use (struct ivopts_data *data, tree *use_p, struct iv *iv, | |
75a70cf9 | 1084 | gimple stmt, enum use_type use_type) |
dec41e98 | 1085 | { |
4c36ffe6 | 1086 | struct iv_use *use = XCNEW (struct iv_use); |
dec41e98 | 1087 | |
1088 | use->id = n_iv_uses (data); | |
1089 | use->type = use_type; | |
1090 | use->iv = iv; | |
1091 | use->stmt = stmt; | |
1092 | use->op_p = use_p; | |
27335ffd | 1093 | use->related_cands = BITMAP_ALLOC (NULL); |
dec41e98 | 1094 | |
065d134e | 1095 | /* To avoid showing ssa name in the dumps, if it was not reset by the |
1096 | caller. */ | |
1097 | iv->ssa_name = NULL_TREE; | |
1098 | ||
dec41e98 | 1099 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1100 | dump_use (dump_file, use); | |
1101 | ||
7d18ea07 | 1102 | VEC_safe_push (iv_use_p, heap, data->iv_uses, use); |
dec41e98 | 1103 | |
1104 | return use; | |
1105 | } | |
1106 | ||
1107 | /* Checks whether OP is a loop-level invariant and if so, records it. | |
1108 | NONLINEAR_USE is true if the invariant is used in a way we do not | |
1109 | handle specially. */ | |
1110 | ||
1111 | static void | |
1112 | record_invariant (struct ivopts_data *data, tree op, bool nonlinear_use) | |
1113 | { | |
1114 | basic_block bb; | |
1115 | struct version_info *info; | |
1116 | ||
1117 | if (TREE_CODE (op) != SSA_NAME | |
1118 | || !is_gimple_reg (op)) | |
1119 | return; | |
1120 | ||
75a70cf9 | 1121 | bb = gimple_bb (SSA_NAME_DEF_STMT (op)); |
dec41e98 | 1122 | if (bb |
1123 | && flow_bb_inside_loop_p (data->current_loop, bb)) | |
1124 | return; | |
1125 | ||
1126 | info = name_info (data, op); | |
1127 | info->name = op; | |
1128 | info->has_nonlin_use |= nonlinear_use; | |
1129 | if (!info->inv_id) | |
1130 | info->inv_id = ++data->max_inv_id; | |
1131 | bitmap_set_bit (data->relevant, SSA_NAME_VERSION (op)); | |
1132 | } | |
1133 | ||
3659c47c | 1134 | /* Checks whether the use OP is interesting and if so, records it. */ |
dec41e98 | 1135 | |
1136 | static struct iv_use * | |
3659c47c | 1137 | find_interesting_uses_op (struct ivopts_data *data, tree op) |
dec41e98 | 1138 | { |
1139 | struct iv *iv; | |
1140 | struct iv *civ; | |
75a70cf9 | 1141 | gimple stmt; |
dec41e98 | 1142 | struct iv_use *use; |
1143 | ||
1144 | if (TREE_CODE (op) != SSA_NAME) | |
1145 | return NULL; | |
1146 | ||
1147 | iv = get_iv (data, op); | |
1148 | if (!iv) | |
1149 | return NULL; | |
1150 | ||
1151 | if (iv->have_use_for) | |
1152 | { | |
1153 | use = iv_use (data, iv->use_id); | |
1154 | ||
3659c47c | 1155 | gcc_assert (use->type == USE_NONLINEAR_EXPR); |
dec41e98 | 1156 | return use; |
1157 | } | |
1158 | ||
7a973feb | 1159 | if (integer_zerop (iv->step)) |
dec41e98 | 1160 | { |
1161 | record_invariant (data, op, true); | |
1162 | return NULL; | |
1163 | } | |
1164 | iv->have_use_for = true; | |
1165 | ||
4c36ffe6 | 1166 | civ = XNEW (struct iv); |
dec41e98 | 1167 | *civ = *iv; |
1168 | ||
1169 | stmt = SSA_NAME_DEF_STMT (op); | |
75a70cf9 | 1170 | gcc_assert (gimple_code (stmt) == GIMPLE_PHI |
1171 | || is_gimple_assign (stmt)); | |
dec41e98 | 1172 | |
3659c47c | 1173 | use = record_use (data, NULL, civ, stmt, USE_NONLINEAR_EXPR); |
dec41e98 | 1174 | iv->use_id = use->id; |
1175 | ||
1176 | return use; | |
1177 | } | |
1178 | ||
75a70cf9 | 1179 | /* Given a condition in statement STMT, checks whether it is a compare |
1180 | of an induction variable and an invariant. If this is the case, | |
1181 | CONTROL_VAR is set to location of the iv, BOUND to the location of | |
1182 | the invariant, IV_VAR and IV_BOUND are set to the corresponding | |
1183 | induction variable descriptions, and true is returned. If this is not | |
1184 | the case, CONTROL_VAR and BOUND are set to the arguments of the | |
1185 | condition and false is returned. */ | |
dec41e98 | 1186 | |
02f8cd87 | 1187 | static bool |
75a70cf9 | 1188 | extract_cond_operands (struct ivopts_data *data, gimple stmt, |
02f8cd87 | 1189 | tree **control_var, tree **bound, |
1190 | struct iv **iv_var, struct iv **iv_bound) | |
1191 | { | |
75a70cf9 | 1192 | /* The objects returned when COND has constant operands. */ |
02f8cd87 | 1193 | static struct iv const_iv; |
1194 | static tree zero; | |
02f8cd87 | 1195 | tree *op0 = &zero, *op1 = &zero, *tmp_op; |
1196 | struct iv *iv0 = &const_iv, *iv1 = &const_iv, *tmp_iv; | |
1197 | bool ret = false; | |
1198 | ||
75a70cf9 | 1199 | if (gimple_code (stmt) == GIMPLE_COND) |
dec41e98 | 1200 | { |
75a70cf9 | 1201 | op0 = gimple_cond_lhs_ptr (stmt); |
1202 | op1 = gimple_cond_rhs_ptr (stmt); | |
dec41e98 | 1203 | } |
75a70cf9 | 1204 | else |
dec41e98 | 1205 | { |
75a70cf9 | 1206 | op0 = gimple_assign_rhs1_ptr (stmt); |
1207 | op1 = gimple_assign_rhs2_ptr (stmt); | |
dec41e98 | 1208 | } |
1209 | ||
75a70cf9 | 1210 | zero = integer_zero_node; |
1211 | const_iv.step = integer_zero_node; | |
1212 | ||
02f8cd87 | 1213 | if (TREE_CODE (*op0) == SSA_NAME) |
1214 | iv0 = get_iv (data, *op0); | |
1215 | if (TREE_CODE (*op1) == SSA_NAME) | |
1216 | iv1 = get_iv (data, *op1); | |
dec41e98 | 1217 | |
02f8cd87 | 1218 | /* Exactly one of the compared values must be an iv, and the other one must |
1219 | be an invariant. */ | |
1220 | if (!iv0 || !iv1) | |
1221 | goto end; | |
1222 | ||
1223 | if (integer_zerop (iv0->step)) | |
1224 | { | |
1225 | /* Control variable may be on the other side. */ | |
1226 | tmp_op = op0; op0 = op1; op1 = tmp_op; | |
1227 | tmp_iv = iv0; iv0 = iv1; iv1 = tmp_iv; | |
dec41e98 | 1228 | } |
02f8cd87 | 1229 | ret = !integer_zerop (iv0->step) && integer_zerop (iv1->step); |
1230 | ||
1231 | end: | |
1232 | if (control_var) | |
1233 | *control_var = op0;; | |
1234 | if (iv_var) | |
1235 | *iv_var = iv0;; | |
1236 | if (bound) | |
1237 | *bound = op1; | |
1238 | if (iv_bound) | |
1239 | *iv_bound = iv1; | |
1240 | ||
1241 | return ret; | |
1242 | } | |
1243 | ||
75a70cf9 | 1244 | /* Checks whether the condition in STMT is interesting and if so, |
1245 | records it. */ | |
02f8cd87 | 1246 | |
1247 | static void | |
75a70cf9 | 1248 | find_interesting_uses_cond (struct ivopts_data *data, gimple stmt) |
02f8cd87 | 1249 | { |
1250 | tree *var_p, *bound_p; | |
1251 | struct iv *var_iv, *civ; | |
dec41e98 | 1252 | |
75a70cf9 | 1253 | if (!extract_cond_operands (data, stmt, &var_p, &bound_p, &var_iv, NULL)) |
dec41e98 | 1254 | { |
02f8cd87 | 1255 | find_interesting_uses_op (data, *var_p); |
1256 | find_interesting_uses_op (data, *bound_p); | |
dec41e98 | 1257 | return; |
1258 | } | |
1259 | ||
4c36ffe6 | 1260 | civ = XNEW (struct iv); |
02f8cd87 | 1261 | *civ = *var_iv; |
75a70cf9 | 1262 | record_use (data, NULL, civ, stmt, USE_COMPARE); |
dec41e98 | 1263 | } |
1264 | ||
a59824bb | 1265 | /* Returns true if expression EXPR is obviously invariant in LOOP, |
663608f5 | 1266 | i.e. if all its operands are defined outside of the LOOP. LOOP |
1267 | should not be the function body. */ | |
a59824bb | 1268 | |
1b5c3dde | 1269 | bool |
a59824bb | 1270 | expr_invariant_in_loop_p (struct loop *loop, tree expr) |
1271 | { | |
1272 | basic_block def_bb; | |
1273 | unsigned i, len; | |
1274 | ||
663608f5 | 1275 | gcc_assert (loop_depth (loop) > 0); |
1276 | ||
a59824bb | 1277 | if (is_gimple_min_invariant (expr)) |
1278 | return true; | |
1279 | ||
1280 | if (TREE_CODE (expr) == SSA_NAME) | |
1281 | { | |
75a70cf9 | 1282 | def_bb = gimple_bb (SSA_NAME_DEF_STMT (expr)); |
a59824bb | 1283 | if (def_bb |
1284 | && flow_bb_inside_loop_p (loop, def_bb)) | |
1285 | return false; | |
1286 | ||
1287 | return true; | |
1288 | } | |
1289 | ||
75a70cf9 | 1290 | if (!EXPR_P (expr)) |
a59824bb | 1291 | return false; |
1292 | ||
c2f47e15 | 1293 | len = TREE_OPERAND_LENGTH (expr); |
a59824bb | 1294 | for (i = 0; i < len; i++) |
1295 | if (!expr_invariant_in_loop_p (loop, TREE_OPERAND (expr, i))) | |
1296 | return false; | |
1297 | ||
1298 | return true; | |
1299 | } | |
1300 | ||
75a70cf9 | 1301 | /* Returns true if statement STMT is obviously invariant in LOOP, |
1302 | i.e. if all its operands on the RHS are defined outside of the LOOP. | |
1303 | LOOP should not be the function body. */ | |
1304 | ||
1305 | bool | |
1306 | stmt_invariant_in_loop_p (struct loop *loop, gimple stmt) | |
1307 | { | |
1308 | unsigned i; | |
1309 | tree lhs; | |
1310 | ||
1311 | gcc_assert (loop_depth (loop) > 0); | |
1312 | ||
1313 | lhs = gimple_get_lhs (stmt); | |
1314 | for (i = 0; i < gimple_num_ops (stmt); i++) | |
1315 | { | |
1316 | tree op = gimple_op (stmt, i); | |
1317 | if (op != lhs && !expr_invariant_in_loop_p (loop, op)) | |
1318 | return false; | |
1319 | } | |
1320 | ||
1321 | return true; | |
1322 | } | |
1323 | ||
dec41e98 | 1324 | /* Cumulates the steps of indices into DATA and replaces their values with the |
1325 | initial ones. Returns false when the value of the index cannot be determined. | |
1326 | Callback for for_each_index. */ | |
1327 | ||
1328 | struct ifs_ivopts_data | |
1329 | { | |
1330 | struct ivopts_data *ivopts_data; | |
75a70cf9 | 1331 | gimple stmt; |
7a973feb | 1332 | tree step; |
dec41e98 | 1333 | }; |
1334 | ||
1335 | static bool | |
1336 | idx_find_step (tree base, tree *idx, void *data) | |
1337 | { | |
f0d6e81c | 1338 | struct ifs_ivopts_data *dta = (struct ifs_ivopts_data *) data; |
dec41e98 | 1339 | struct iv *iv; |
57e3f39a | 1340 | tree step, iv_base, iv_step, lbound, off; |
dbc64c75 | 1341 | struct loop *loop = dta->ivopts_data->current_loop; |
a59824bb | 1342 | |
1343 | if (TREE_CODE (base) == MISALIGNED_INDIRECT_REF | |
1344 | || TREE_CODE (base) == ALIGN_INDIRECT_REF) | |
1345 | return false; | |
1346 | ||
1347 | /* If base is a component ref, require that the offset of the reference | |
f7406879 | 1348 | be invariant. */ |
a59824bb | 1349 | if (TREE_CODE (base) == COMPONENT_REF) |
1350 | { | |
1351 | off = component_ref_field_offset (base); | |
1352 | return expr_invariant_in_loop_p (loop, off); | |
1353 | } | |
1354 | ||
1355 | /* If base is array, first check whether we will be able to move the | |
1356 | reference out of the loop (in order to take its address in strength | |
1357 | reduction). In order for this to work we need both lower bound | |
1358 | and step to be loop invariants. */ | |
5e19919e | 1359 | if (TREE_CODE (base) == ARRAY_REF || TREE_CODE (base) == ARRAY_RANGE_REF) |
a59824bb | 1360 | { |
5e19919e | 1361 | /* Moreover, for a range, the size needs to be invariant as well. */ |
1362 | if (TREE_CODE (base) == ARRAY_RANGE_REF | |
1363 | && !expr_invariant_in_loop_p (loop, TYPE_SIZE (TREE_TYPE (base)))) | |
1364 | return false; | |
1365 | ||
a59824bb | 1366 | step = array_ref_element_size (base); |
1367 | lbound = array_ref_low_bound (base); | |
1368 | ||
1369 | if (!expr_invariant_in_loop_p (loop, step) | |
1370 | || !expr_invariant_in_loop_p (loop, lbound)) | |
1371 | return false; | |
1372 | } | |
1373 | ||
dec41e98 | 1374 | if (TREE_CODE (*idx) != SSA_NAME) |
1375 | return true; | |
1376 | ||
1377 | iv = get_iv (dta->ivopts_data, *idx); | |
1378 | if (!iv) | |
1379 | return false; | |
1380 | ||
d3d02a88 | 1381 | /* XXX We produce for a base of *D42 with iv->base being &x[0] |
1382 | *&x[0], which is not folded and does not trigger the | |
1383 | ARRAY_REF path below. */ | |
dec41e98 | 1384 | *idx = iv->base; |
1385 | ||
7a973feb | 1386 | if (integer_zerop (iv->step)) |
dec41e98 | 1387 | return true; |
1388 | ||
5e19919e | 1389 | if (TREE_CODE (base) == ARRAY_REF || TREE_CODE (base) == ARRAY_RANGE_REF) |
dbc64c75 | 1390 | { |
1391 | step = array_ref_element_size (base); | |
dbc64c75 | 1392 | |
1393 | /* We only handle addresses whose step is an integer constant. */ | |
1394 | if (TREE_CODE (step) != INTEGER_CST) | |
1395 | return false; | |
dbc64c75 | 1396 | } |
dec41e98 | 1397 | else |
779b4c41 | 1398 | /* The step for pointer arithmetics already is 1 byte. */ |
0213c30e | 1399 | step = build_int_cst (sizetype, 1); |
dec41e98 | 1400 | |
57e3f39a | 1401 | iv_base = iv->base; |
1402 | iv_step = iv->step; | |
1403 | if (!convert_affine_scev (dta->ivopts_data->current_loop, | |
1404 | sizetype, &iv_base, &iv_step, dta->stmt, | |
1405 | false)) | |
dec41e98 | 1406 | { |
1407 | /* The index might wrap. */ | |
1408 | return false; | |
1409 | } | |
1410 | ||
0213c30e | 1411 | step = fold_build2 (MULT_EXPR, sizetype, step, iv_step); |
7a973feb | 1412 | dta->step = fold_build2 (PLUS_EXPR, sizetype, dta->step, step); |
dec41e98 | 1413 | |
1414 | return true; | |
1415 | } | |
1416 | ||
1417 | /* Records use in index IDX. Callback for for_each_index. Ivopts data | |
1418 | object is passed to it in DATA. */ | |
1419 | ||
1420 | static bool | |
dbc64c75 | 1421 | idx_record_use (tree base, tree *idx, |
f0d6e81c | 1422 | void *vdata) |
dec41e98 | 1423 | { |
f0d6e81c | 1424 | struct ivopts_data *data = (struct ivopts_data *) vdata; |
dec41e98 | 1425 | find_interesting_uses_op (data, *idx); |
5e19919e | 1426 | if (TREE_CODE (base) == ARRAY_REF || TREE_CODE (base) == ARRAY_RANGE_REF) |
dbc64c75 | 1427 | { |
1428 | find_interesting_uses_op (data, array_ref_element_size (base)); | |
1429 | find_interesting_uses_op (data, array_ref_low_bound (base)); | |
1430 | } | |
dec41e98 | 1431 | return true; |
1432 | } | |
1433 | ||
90bd1b58 | 1434 | /* If we can prove that TOP = cst * BOT for some constant cst, |
1435 | store cst to MUL and return true. Otherwise return false. | |
1436 | The returned value is always sign-extended, regardless of the | |
1437 | signedness of TOP and BOT. */ | |
1438 | ||
1439 | static bool | |
1440 | constant_multiple_of (tree top, tree bot, double_int *mul) | |
1441 | { | |
1442 | tree mby; | |
1443 | enum tree_code code; | |
1444 | double_int res, p0, p1; | |
1445 | unsigned precision = TYPE_PRECISION (TREE_TYPE (top)); | |
1446 | ||
1447 | STRIP_NOPS (top); | |
1448 | STRIP_NOPS (bot); | |
1449 | ||
1450 | if (operand_equal_p (top, bot, 0)) | |
1451 | { | |
1452 | *mul = double_int_one; | |
1453 | return true; | |
1454 | } | |
1455 | ||
1456 | code = TREE_CODE (top); | |
1457 | switch (code) | |
1458 | { | |
1459 | case MULT_EXPR: | |
1460 | mby = TREE_OPERAND (top, 1); | |
1461 | if (TREE_CODE (mby) != INTEGER_CST) | |
1462 | return false; | |
1463 | ||
1464 | if (!constant_multiple_of (TREE_OPERAND (top, 0), bot, &res)) | |
1465 | return false; | |
1466 | ||
1467 | *mul = double_int_sext (double_int_mul (res, tree_to_double_int (mby)), | |
1468 | precision); | |
1469 | return true; | |
1470 | ||
1471 | case PLUS_EXPR: | |
1472 | case MINUS_EXPR: | |
1473 | if (!constant_multiple_of (TREE_OPERAND (top, 0), bot, &p0) | |
1474 | || !constant_multiple_of (TREE_OPERAND (top, 1), bot, &p1)) | |
1475 | return false; | |
1476 | ||
1477 | if (code == MINUS_EXPR) | |
1478 | p1 = double_int_neg (p1); | |
1479 | *mul = double_int_sext (double_int_add (p0, p1), precision); | |
1480 | return true; | |
1481 | ||
1482 | case INTEGER_CST: | |
1483 | if (TREE_CODE (bot) != INTEGER_CST) | |
1484 | return false; | |
1485 | ||
1486 | p0 = double_int_sext (tree_to_double_int (top), precision); | |
1487 | p1 = double_int_sext (tree_to_double_int (bot), precision); | |
1488 | if (double_int_zero_p (p1)) | |
1489 | return false; | |
1490 | *mul = double_int_sext (double_int_sdivmod (p0, p1, FLOOR_DIV_EXPR, &res), | |
1491 | precision); | |
1492 | return double_int_zero_p (res); | |
1493 | ||
1494 | default: | |
1495 | return false; | |
1496 | } | |
1497 | } | |
1498 | ||
1499 | /* Returns true if memory reference REF with step STEP may be unaligned. */ | |
f63992c3 | 1500 | |
1501 | static bool | |
90bd1b58 | 1502 | may_be_unaligned_p (tree ref, tree step) |
f63992c3 | 1503 | { |
1504 | tree base; | |
1505 | tree base_type; | |
1506 | HOST_WIDE_INT bitsize; | |
1507 | HOST_WIDE_INT bitpos; | |
1508 | tree toffset; | |
1509 | enum machine_mode mode; | |
1510 | int unsignedp, volatilep; | |
1511 | unsigned base_align; | |
1512 | ||
aed164c3 | 1513 | /* TARGET_MEM_REFs are translated directly to valid MEMs on the target, |
ce10738f | 1514 | thus they are not misaligned. */ |
aed164c3 | 1515 | if (TREE_CODE (ref) == TARGET_MEM_REF) |
1516 | return false; | |
1517 | ||
f63992c3 | 1518 | /* The test below is basically copy of what expr.c:normal_inner_ref |
1519 | does to check whether the object must be loaded by parts when | |
1520 | STRICT_ALIGNMENT is true. */ | |
1521 | base = get_inner_reference (ref, &bitsize, &bitpos, &toffset, &mode, | |
1522 | &unsignedp, &volatilep, true); | |
1523 | base_type = TREE_TYPE (base); | |
1524 | base_align = TYPE_ALIGN (base_type); | |
1525 | ||
90bd1b58 | 1526 | if (mode != BLKmode) |
1527 | { | |
1528 | double_int mul; | |
1529 | tree al = build_int_cst (TREE_TYPE (step), | |
1530 | GET_MODE_ALIGNMENT (mode) / BITS_PER_UNIT); | |
1531 | ||
1532 | if (base_align < GET_MODE_ALIGNMENT (mode) | |
f63992c3 | 1533 | || bitpos % GET_MODE_ALIGNMENT (mode) != 0 |
90bd1b58 | 1534 | || bitpos % BITS_PER_UNIT != 0) |
1535 | return true; | |
1536 | ||
a379b1cb | 1537 | if (!constant_multiple_of (step, al, &mul)) |
90bd1b58 | 1538 | return true; |
1539 | } | |
f63992c3 | 1540 | |
1541 | return false; | |
1542 | } | |
1543 | ||
8ee578c8 | 1544 | /* Return true if EXPR may be non-addressable. */ |
1545 | ||
1546 | static bool | |
1547 | may_be_nonaddressable_p (tree expr) | |
1548 | { | |
1549 | switch (TREE_CODE (expr)) | |
1550 | { | |
0e41e637 | 1551 | case TARGET_MEM_REF: |
1552 | /* TARGET_MEM_REFs are translated directly to valid MEMs on the | |
1553 | target, thus they are always addressable. */ | |
1554 | return false; | |
1555 | ||
8ee578c8 | 1556 | case COMPONENT_REF: |
1557 | return DECL_NONADDRESSABLE_P (TREE_OPERAND (expr, 1)) | |
1558 | || may_be_nonaddressable_p (TREE_OPERAND (expr, 0)); | |
1559 | ||
8ee578c8 | 1560 | case VIEW_CONVERT_EXPR: |
1561 | /* This kind of view-conversions may wrap non-addressable objects | |
1562 | and make them look addressable. After some processing the | |
1563 | non-addressability may be uncovered again, causing ADDR_EXPRs | |
1564 | of inappropriate objects to be built. */ | |
2a8afb23 | 1565 | if (is_gimple_reg (TREE_OPERAND (expr, 0)) |
1566 | || !is_gimple_addressable (TREE_OPERAND (expr, 0))) | |
1567 | return true; | |
1568 | ||
1569 | /* ... fall through ... */ | |
0e41e637 | 1570 | |
1571 | case ARRAY_REF: | |
1572 | case ARRAY_RANGE_REF: | |
2a8afb23 | 1573 | return may_be_nonaddressable_p (TREE_OPERAND (expr, 0)); |
0e41e637 | 1574 | |
72dd6141 | 1575 | CASE_CONVERT: |
0e41e637 | 1576 | return true; |
8ee578c8 | 1577 | |
1578 | default: | |
1579 | break; | |
1580 | } | |
1581 | ||
1582 | return false; | |
1583 | } | |
1584 | ||
dec41e98 | 1585 | /* Finds addresses in *OP_P inside STMT. */ |
1586 | ||
1587 | static void | |
75a70cf9 | 1588 | find_interesting_uses_address (struct ivopts_data *data, gimple stmt, tree *op_p) |
dec41e98 | 1589 | { |
7a973feb | 1590 | tree base = *op_p, step = build_int_cst (sizetype, 0); |
dec41e98 | 1591 | struct iv *civ; |
1592 | struct ifs_ivopts_data ifs_ivopts_data; | |
1593 | ||
281baea1 | 1594 | /* Do not play with volatile memory references. A bit too conservative, |
1595 | perhaps, but safe. */ | |
75a70cf9 | 1596 | if (gimple_has_volatile_ops (stmt)) |
281baea1 | 1597 | goto fail; |
1598 | ||
dec41e98 | 1599 | /* Ignore bitfields for now. Not really something terribly complicated |
1600 | to handle. TODO. */ | |
8ee578c8 | 1601 | if (TREE_CODE (base) == BIT_FIELD_REF) |
1602 | goto fail; | |
1603 | ||
aed164c3 | 1604 | base = unshare_expr (base); |
1605 | ||
1606 | if (TREE_CODE (base) == TARGET_MEM_REF) | |
1607 | { | |
1608 | tree type = build_pointer_type (TREE_TYPE (base)); | |
1609 | tree astep; | |
1610 | ||
1611 | if (TMR_BASE (base) | |
1612 | && TREE_CODE (TMR_BASE (base)) == SSA_NAME) | |
1613 | { | |
1614 | civ = get_iv (data, TMR_BASE (base)); | |
1615 | if (!civ) | |
1616 | goto fail; | |
1617 | ||
1618 | TMR_BASE (base) = civ->base; | |
1619 | step = civ->step; | |
1620 | } | |
1621 | if (TMR_INDEX (base) | |
1622 | && TREE_CODE (TMR_INDEX (base)) == SSA_NAME) | |
1623 | { | |
1624 | civ = get_iv (data, TMR_INDEX (base)); | |
1625 | if (!civ) | |
1626 | goto fail; | |
dec41e98 | 1627 | |
aed164c3 | 1628 | TMR_INDEX (base) = civ->base; |
1629 | astep = civ->step; | |
a59824bb | 1630 | |
aed164c3 | 1631 | if (astep) |
1632 | { | |
1633 | if (TMR_STEP (base)) | |
1634 | astep = fold_build2 (MULT_EXPR, type, TMR_STEP (base), astep); | |
1635 | ||
7a973feb | 1636 | step = fold_build2 (PLUS_EXPR, type, step, astep); |
aed164c3 | 1637 | } |
1638 | } | |
1639 | ||
7a973feb | 1640 | if (integer_zerop (step)) |
aed164c3 | 1641 | goto fail; |
1642 | base = tree_mem_ref_addr (type, base); | |
1643 | } | |
1644 | else | |
1645 | { | |
1646 | ifs_ivopts_data.ivopts_data = data; | |
1647 | ifs_ivopts_data.stmt = stmt; | |
7a973feb | 1648 | ifs_ivopts_data.step = build_int_cst (sizetype, 0); |
aed164c3 | 1649 | if (!for_each_index (&base, idx_find_step, &ifs_ivopts_data) |
7a973feb | 1650 | || integer_zerop (ifs_ivopts_data.step)) |
aed164c3 | 1651 | goto fail; |
7a973feb | 1652 | step = ifs_ivopts_data.step; |
aed164c3 | 1653 | |
1654 | gcc_assert (TREE_CODE (base) != ALIGN_INDIRECT_REF); | |
1655 | gcc_assert (TREE_CODE (base) != MISALIGNED_INDIRECT_REF); | |
1656 | ||
0e41e637 | 1657 | /* Check that the base expression is addressable. This needs |
1658 | to be done after substituting bases of IVs into it. */ | |
1659 | if (may_be_nonaddressable_p (base)) | |
1660 | goto fail; | |
1661 | ||
1662 | /* Moreover, on strict alignment platforms, check that it is | |
1663 | sufficiently aligned. */ | |
90bd1b58 | 1664 | if (STRICT_ALIGNMENT && may_be_unaligned_p (base, step)) |
0e41e637 | 1665 | goto fail; |
1666 | ||
aed164c3 | 1667 | base = build_fold_addr_expr (base); |
d3d02a88 | 1668 | |
1669 | /* Substituting bases of IVs into the base expression might | |
1670 | have caused folding opportunities. */ | |
1671 | if (TREE_CODE (base) == ADDR_EXPR) | |
1672 | { | |
1673 | tree *ref = &TREE_OPERAND (base, 0); | |
1674 | while (handled_component_p (*ref)) | |
1675 | ref = &TREE_OPERAND (*ref, 0); | |
1676 | if (TREE_CODE (*ref) == INDIRECT_REF) | |
1677 | *ref = fold_indirect_ref (*ref); | |
1678 | } | |
aed164c3 | 1679 | } |
dec41e98 | 1680 | |
1681 | civ = alloc_iv (base, step); | |
1682 | record_use (data, op_p, civ, stmt, USE_ADDRESS); | |
1683 | return; | |
1684 | ||
1685 | fail: | |
1686 | for_each_index (op_p, idx_record_use, data); | |
1687 | } | |
1688 | ||
1689 | /* Finds and records invariants used in STMT. */ | |
1690 | ||
1691 | static void | |
75a70cf9 | 1692 | find_invariants_stmt (struct ivopts_data *data, gimple stmt) |
dec41e98 | 1693 | { |
b66731e8 | 1694 | ssa_op_iter iter; |
1695 | use_operand_p use_p; | |
dec41e98 | 1696 | tree op; |
1697 | ||
b66731e8 | 1698 | FOR_EACH_PHI_OR_STMT_USE (use_p, stmt, iter, SSA_OP_USE) |
dec41e98 | 1699 | { |
b66731e8 | 1700 | op = USE_FROM_PTR (use_p); |
dec41e98 | 1701 | record_invariant (data, op, false); |
1702 | } | |
1703 | } | |
1704 | ||
1705 | /* Finds interesting uses of induction variables in the statement STMT. */ | |
1706 | ||
1707 | static void | |
75a70cf9 | 1708 | find_interesting_uses_stmt (struct ivopts_data *data, gimple stmt) |
dec41e98 | 1709 | { |
1710 | struct iv *iv; | |
75a70cf9 | 1711 | tree op, *lhs, *rhs; |
b66731e8 | 1712 | ssa_op_iter iter; |
1713 | use_operand_p use_p; | |
75a70cf9 | 1714 | enum tree_code code; |
dec41e98 | 1715 | |
1716 | find_invariants_stmt (data, stmt); | |
1717 | ||
75a70cf9 | 1718 | if (gimple_code (stmt) == GIMPLE_COND) |
dec41e98 | 1719 | { |
75a70cf9 | 1720 | find_interesting_uses_cond (data, stmt); |
dec41e98 | 1721 | return; |
1722 | } | |
1723 | ||
75a70cf9 | 1724 | if (is_gimple_assign (stmt)) |
dec41e98 | 1725 | { |
75a70cf9 | 1726 | lhs = gimple_assign_lhs_ptr (stmt); |
1727 | rhs = gimple_assign_rhs1_ptr (stmt); | |
dec41e98 | 1728 | |
75a70cf9 | 1729 | if (TREE_CODE (*lhs) == SSA_NAME) |
dec41e98 | 1730 | { |
1731 | /* If the statement defines an induction variable, the uses are not | |
1732 | interesting by themselves. */ | |
1733 | ||
75a70cf9 | 1734 | iv = get_iv (data, *lhs); |
dec41e98 | 1735 | |
7a973feb | 1736 | if (iv && !integer_zerop (iv->step)) |
dec41e98 | 1737 | return; |
1738 | } | |
1739 | ||
75a70cf9 | 1740 | code = gimple_assign_rhs_code (stmt); |
1741 | if (get_gimple_rhs_class (code) == GIMPLE_SINGLE_RHS | |
1742 | && (REFERENCE_CLASS_P (*rhs) | |
1743 | || is_gimple_val (*rhs))) | |
dec41e98 | 1744 | { |
75a70cf9 | 1745 | if (REFERENCE_CLASS_P (*rhs)) |
1746 | find_interesting_uses_address (data, stmt, rhs); | |
1747 | else | |
1748 | find_interesting_uses_op (data, *rhs); | |
dec41e98 | 1749 | |
75a70cf9 | 1750 | if (REFERENCE_CLASS_P (*lhs)) |
1751 | find_interesting_uses_address (data, stmt, lhs); | |
dec41e98 | 1752 | return; |
dec41e98 | 1753 | } |
75a70cf9 | 1754 | else if (TREE_CODE_CLASS (code) == tcc_comparison) |
dec41e98 | 1755 | { |
75a70cf9 | 1756 | find_interesting_uses_cond (data, stmt); |
dec41e98 | 1757 | return; |
1758 | } | |
dbc64c75 | 1759 | |
1760 | /* TODO -- we should also handle address uses of type | |
1761 | ||
1762 | memory = call (whatever); | |
1763 | ||
1764 | and | |
1765 | ||
1766 | call (memory). */ | |
dec41e98 | 1767 | } |
1768 | ||
75a70cf9 | 1769 | if (gimple_code (stmt) == GIMPLE_PHI |
1770 | && gimple_bb (stmt) == data->current_loop->header) | |
dec41e98 | 1771 | { |
75a70cf9 | 1772 | iv = get_iv (data, PHI_RESULT (stmt)); |
dec41e98 | 1773 | |
7a973feb | 1774 | if (iv && !integer_zerop (iv->step)) |
dec41e98 | 1775 | return; |
1776 | } | |
1777 | ||
b66731e8 | 1778 | FOR_EACH_PHI_OR_STMT_USE (use_p, stmt, iter, SSA_OP_USE) |
dec41e98 | 1779 | { |
b66731e8 | 1780 | op = USE_FROM_PTR (use_p); |
dec41e98 | 1781 | |
1782 | if (TREE_CODE (op) != SSA_NAME) | |
1783 | continue; | |
1784 | ||
1785 | iv = get_iv (data, op); | |
1786 | if (!iv) | |
1787 | continue; | |
1788 | ||
1789 | find_interesting_uses_op (data, op); | |
1790 | } | |
1791 | } | |
1792 | ||
1793 | /* Finds interesting uses of induction variables outside of loops | |
1794 | on loop exit edge EXIT. */ | |
1795 | ||
1796 | static void | |
1797 | find_interesting_uses_outside (struct ivopts_data *data, edge exit) | |
1798 | { | |
75a70cf9 | 1799 | gimple phi; |
1800 | gimple_stmt_iterator psi; | |
1801 | tree def; | |
dec41e98 | 1802 | |
75a70cf9 | 1803 | for (psi = gsi_start_phis (exit->dest); !gsi_end_p (psi); gsi_next (&psi)) |
dec41e98 | 1804 | { |
75a70cf9 | 1805 | phi = gsi_stmt (psi); |
dec41e98 | 1806 | def = PHI_ARG_DEF_FROM_EDGE (phi, exit); |
7a973feb | 1807 | if (is_gimple_reg (def)) |
1808 | find_interesting_uses_op (data, def); | |
dec41e98 | 1809 | } |
1810 | } | |
1811 | ||
1812 | /* Finds uses of the induction variables that are interesting. */ | |
1813 | ||
1814 | static void | |
1815 | find_interesting_uses (struct ivopts_data *data) | |
1816 | { | |
1817 | basic_block bb; | |
75a70cf9 | 1818 | gimple_stmt_iterator bsi; |
dec41e98 | 1819 | basic_block *body = get_loop_body (data->current_loop); |
1820 | unsigned i; | |
1821 | struct version_info *info; | |
1822 | edge e; | |
1823 | ||
1824 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1825 | fprintf (dump_file, "Uses:\n\n"); | |
1826 | ||
1827 | for (i = 0; i < data->current_loop->num_nodes; i++) | |
1828 | { | |
cd665a06 | 1829 | edge_iterator ei; |
dec41e98 | 1830 | bb = body[i]; |
1831 | ||
cd665a06 | 1832 | FOR_EACH_EDGE (e, ei, bb->succs) |
dec41e98 | 1833 | if (e->dest != EXIT_BLOCK_PTR |
1834 | && !flow_bb_inside_loop_p (data->current_loop, e->dest)) | |
1835 | find_interesting_uses_outside (data, e); | |
1836 | ||
75a70cf9 | 1837 | for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) |
1838 | find_interesting_uses_stmt (data, gsi_stmt (bsi)); | |
1839 | for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) | |
1840 | find_interesting_uses_stmt (data, gsi_stmt (bsi)); | |
dec41e98 | 1841 | } |
1842 | ||
1843 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1844 | { | |
0cc4271a | 1845 | bitmap_iterator bi; |
1846 | ||
dec41e98 | 1847 | fprintf (dump_file, "\n"); |
1848 | ||
0cc4271a | 1849 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
dec41e98 | 1850 | { |
1851 | info = ver_info (data, i); | |
1852 | if (info->inv_id) | |
1853 | { | |
1854 | fprintf (dump_file, " "); | |
1855 | print_generic_expr (dump_file, info->name, TDF_SLIM); | |
1856 | fprintf (dump_file, " is invariant (%d)%s\n", | |
1857 | info->inv_id, info->has_nonlin_use ? "" : ", eliminable"); | |
1858 | } | |
0cc4271a | 1859 | } |
dec41e98 | 1860 | |
1861 | fprintf (dump_file, "\n"); | |
1862 | } | |
1863 | ||
1864 | free (body); | |
1865 | } | |
1866 | ||
390955a6 | 1867 | /* Strips constant offsets from EXPR and stores them to OFFSET. If INSIDE_ADDR |
651874e1 | 1868 | is true, assume we are inside an address. If TOP_COMPREF is true, assume |
1869 | we are at the top-level of the processed address. */ | |
390955a6 | 1870 | |
1871 | static tree | |
651874e1 | 1872 | strip_offset_1 (tree expr, bool inside_addr, bool top_compref, |
1873 | unsigned HOST_WIDE_INT *offset) | |
390955a6 | 1874 | { |
651874e1 | 1875 | tree op0 = NULL_TREE, op1 = NULL_TREE, tmp, step; |
390955a6 | 1876 | enum tree_code code; |
1877 | tree type, orig_type = TREE_TYPE (expr); | |
1878 | unsigned HOST_WIDE_INT off0, off1, st; | |
1879 | tree orig_expr = expr; | |
1880 | ||
1881 | STRIP_NOPS (expr); | |
651874e1 | 1882 | |
390955a6 | 1883 | type = TREE_TYPE (expr); |
1884 | code = TREE_CODE (expr); | |
1885 | *offset = 0; | |
1886 | ||
1887 | switch (code) | |
1888 | { | |
1889 | case INTEGER_CST: | |
1890 | if (!cst_and_fits_in_hwi (expr) | |
cd743a11 | 1891 | || integer_zerop (expr)) |
390955a6 | 1892 | return orig_expr; |
1893 | ||
1894 | *offset = int_cst_value (expr); | |
05db596e | 1895 | return build_int_cst (orig_type, 0); |
390955a6 | 1896 | |
2595dcbb | 1897 | case POINTER_PLUS_EXPR: |
390955a6 | 1898 | case PLUS_EXPR: |
1899 | case MINUS_EXPR: | |
1900 | op0 = TREE_OPERAND (expr, 0); | |
1901 | op1 = TREE_OPERAND (expr, 1); | |
1902 | ||
651874e1 | 1903 | op0 = strip_offset_1 (op0, false, false, &off0); |
1904 | op1 = strip_offset_1 (op1, false, false, &off1); | |
390955a6 | 1905 | |
2595dcbb | 1906 | *offset = (code == MINUS_EXPR ? off0 - off1 : off0 + off1); |
390955a6 | 1907 | if (op0 == TREE_OPERAND (expr, 0) |
1908 | && op1 == TREE_OPERAND (expr, 1)) | |
1909 | return orig_expr; | |
1910 | ||
cd743a11 | 1911 | if (integer_zerop (op1)) |
390955a6 | 1912 | expr = op0; |
cd743a11 | 1913 | else if (integer_zerop (op0)) |
390955a6 | 1914 | { |
2595dcbb | 1915 | if (code == MINUS_EXPR) |
651874e1 | 1916 | expr = fold_build1 (NEGATE_EXPR, type, op1); |
2595dcbb | 1917 | else |
1918 | expr = op1; | |
390955a6 | 1919 | } |
1920 | else | |
651874e1 | 1921 | expr = fold_build2 (code, type, op0, op1); |
390955a6 | 1922 | |
1923 | return fold_convert (orig_type, expr); | |
1924 | ||
1925 | case ARRAY_REF: | |
5e19919e | 1926 | case ARRAY_RANGE_REF: |
390955a6 | 1927 | if (!inside_addr) |
1928 | return orig_expr; | |
1929 | ||
1930 | step = array_ref_element_size (expr); | |
1931 | if (!cst_and_fits_in_hwi (step)) | |
1932 | break; | |
1933 | ||
1934 | st = int_cst_value (step); | |
1935 | op1 = TREE_OPERAND (expr, 1); | |
651874e1 | 1936 | op1 = strip_offset_1 (op1, false, false, &off1); |
390955a6 | 1937 | *offset = off1 * st; |
651874e1 | 1938 | |
1939 | if (top_compref | |
cd743a11 | 1940 | && integer_zerop (op1)) |
651874e1 | 1941 | { |
1942 | /* Strip the component reference completely. */ | |
1943 | op0 = TREE_OPERAND (expr, 0); | |
1944 | op0 = strip_offset_1 (op0, inside_addr, top_compref, &off0); | |
1945 | *offset += off0; | |
1946 | return op0; | |
1947 | } | |
390955a6 | 1948 | break; |
1949 | ||
1950 | case COMPONENT_REF: | |
1951 | if (!inside_addr) | |
1952 | return orig_expr; | |
651874e1 | 1953 | |
1954 | tmp = component_ref_field_offset (expr); | |
1955 | if (top_compref | |
1956 | && cst_and_fits_in_hwi (tmp)) | |
1957 | { | |
1958 | /* Strip the component reference completely. */ | |
1959 | op0 = TREE_OPERAND (expr, 0); | |
1960 | op0 = strip_offset_1 (op0, inside_addr, top_compref, &off0); | |
1961 | *offset = off0 + int_cst_value (tmp); | |
1962 | return op0; | |
1963 | } | |
390955a6 | 1964 | break; |
1965 | ||
1966 | case ADDR_EXPR: | |
651874e1 | 1967 | op0 = TREE_OPERAND (expr, 0); |
1968 | op0 = strip_offset_1 (op0, true, true, &off0); | |
1969 | *offset += off0; | |
1970 | ||
1971 | if (op0 == TREE_OPERAND (expr, 0)) | |
1972 | return orig_expr; | |
1973 | ||
8cb6f421 | 1974 | expr = build_fold_addr_expr (op0); |
651874e1 | 1975 | return fold_convert (orig_type, expr); |
1976 | ||
1977 | case INDIRECT_REF: | |
1978 | inside_addr = false; | |
390955a6 | 1979 | break; |
1980 | ||
1981 | default: | |
1982 | return orig_expr; | |
1983 | } | |
1984 | ||
1985 | /* Default handling of expressions for that we want to recurse into | |
1986 | the first operand. */ | |
1987 | op0 = TREE_OPERAND (expr, 0); | |
651874e1 | 1988 | op0 = strip_offset_1 (op0, inside_addr, false, &off0); |
390955a6 | 1989 | *offset += off0; |
1990 | ||
1991 | if (op0 == TREE_OPERAND (expr, 0) | |
1992 | && (!op1 || op1 == TREE_OPERAND (expr, 1))) | |
1993 | return orig_expr; | |
1994 | ||
1995 | expr = copy_node (expr); | |
1996 | TREE_OPERAND (expr, 0) = op0; | |
1997 | if (op1) | |
1998 | TREE_OPERAND (expr, 1) = op1; | |
1999 | ||
651874e1 | 2000 | /* Inside address, we might strip the top level component references, |
442e3cb9 | 2001 | thus changing type of the expression. Handling of ADDR_EXPR |
651874e1 | 2002 | will fix that. */ |
2003 | expr = fold_convert (orig_type, expr); | |
2004 | ||
2005 | return expr; | |
2006 | } | |
2007 | ||
2008 | /* Strips constant offsets from EXPR and stores them to OFFSET. */ | |
2009 | ||
2010 | static tree | |
2011 | strip_offset (tree expr, unsigned HOST_WIDE_INT *offset) | |
2012 | { | |
2013 | return strip_offset_1 (expr, false, false, offset); | |
390955a6 | 2014 | } |
2015 | ||
d086c307 | 2016 | /* Returns variant of TYPE that can be used as base for different uses. |
318a3281 | 2017 | We return unsigned type with the same precision, which avoids problems |
2018 | with overflows. */ | |
d086c307 | 2019 | |
2020 | static tree | |
2021 | generic_type_for (tree type) | |
2022 | { | |
2023 | if (POINTER_TYPE_P (type)) | |
318a3281 | 2024 | return unsigned_type_for (type); |
d086c307 | 2025 | |
2026 | if (TYPE_UNSIGNED (type)) | |
2027 | return type; | |
2028 | ||
2029 | return unsigned_type_for (type); | |
2030 | } | |
2031 | ||
651874e1 | 2032 | /* Records invariants in *EXPR_P. Callback for walk_tree. DATA contains |
2033 | the bitmap to that we should store it. */ | |
2034 | ||
2035 | static struct ivopts_data *fd_ivopts_data; | |
2036 | static tree | |
2037 | find_depends (tree *expr_p, int *ws ATTRIBUTE_UNUSED, void *data) | |
2038 | { | |
f0d6e81c | 2039 | bitmap *depends_on = (bitmap *) data; |
651874e1 | 2040 | struct version_info *info; |
2041 | ||
2042 | if (TREE_CODE (*expr_p) != SSA_NAME) | |
2043 | return NULL_TREE; | |
2044 | info = name_info (fd_ivopts_data, *expr_p); | |
2045 | ||
2046 | if (!info->inv_id || info->has_nonlin_use) | |
2047 | return NULL_TREE; | |
2048 | ||
2049 | if (!*depends_on) | |
2050 | *depends_on = BITMAP_ALLOC (NULL); | |
2051 | bitmap_set_bit (*depends_on, info->inv_id); | |
2052 | ||
2053 | return NULL_TREE; | |
2054 | } | |
2055 | ||
dec41e98 | 2056 | /* Adds a candidate BASE + STEP * i. Important field is set to IMPORTANT and |
2057 | position to POS. If USE is not NULL, the candidate is set as related to | |
2058 | it. If both BASE and STEP are NULL, we add a pseudocandidate for the | |
2059 | replacement of the final value of the iv by a direct computation. */ | |
2060 | ||
2061 | static struct iv_cand * | |
2062 | add_candidate_1 (struct ivopts_data *data, | |
2063 | tree base, tree step, bool important, enum iv_position pos, | |
75a70cf9 | 2064 | struct iv_use *use, gimple incremented_at) |
dec41e98 | 2065 | { |
2066 | unsigned i; | |
2067 | struct iv_cand *cand = NULL; | |
d086c307 | 2068 | tree type, orig_type; |
dec41e98 | 2069 | |
2070 | if (base) | |
2071 | { | |
d086c307 | 2072 | orig_type = TREE_TYPE (base); |
2073 | type = generic_type_for (orig_type); | |
29474274 | 2074 | if (type != orig_type) |
dec41e98 | 2075 | { |
dec41e98 | 2076 | base = fold_convert (type, base); |
7a973feb | 2077 | step = fold_convert (type, step); |
dec41e98 | 2078 | } |
2079 | } | |
2080 | ||
2081 | for (i = 0; i < n_iv_cands (data); i++) | |
2082 | { | |
2083 | cand = iv_cand (data, i); | |
2084 | ||
2085 | if (cand->pos != pos) | |
2086 | continue; | |
2087 | ||
2088 | if (cand->incremented_at != incremented_at) | |
2089 | continue; | |
2090 | ||
2091 | if (!cand->iv) | |
2092 | { | |
2093 | if (!base && !step) | |
2094 | break; | |
2095 | ||
2096 | continue; | |
2097 | } | |
2098 | ||
2099 | if (!base && !step) | |
2100 | continue; | |
2101 | ||
7a973feb | 2102 | if (operand_equal_p (base, cand->iv->base, 0) |
2103 | && operand_equal_p (step, cand->iv->step, 0)) | |
2104 | break; | |
dec41e98 | 2105 | } |
2106 | ||
2107 | if (i == n_iv_cands (data)) | |
2108 | { | |
4c36ffe6 | 2109 | cand = XCNEW (struct iv_cand); |
dec41e98 | 2110 | cand->id = i; |
2111 | ||
2112 | if (!base && !step) | |
2113 | cand->iv = NULL; | |
2114 | else | |
2115 | cand->iv = alloc_iv (base, step); | |
2116 | ||
2117 | cand->pos = pos; | |
2118 | if (pos != IP_ORIGINAL && cand->iv) | |
2119 | { | |
2120 | cand->var_before = create_tmp_var_raw (TREE_TYPE (base), "ivtmp"); | |
2121 | cand->var_after = cand->var_before; | |
2122 | } | |
2123 | cand->important = important; | |
2124 | cand->incremented_at = incremented_at; | |
7d18ea07 | 2125 | VEC_safe_push (iv_cand_p, heap, data->iv_candidates, cand); |
dec41e98 | 2126 | |
651874e1 | 2127 | if (step |
2128 | && TREE_CODE (step) != INTEGER_CST) | |
2129 | { | |
2130 | fd_ivopts_data = data; | |
2131 | walk_tree (&step, find_depends, &cand->depends_on, NULL); | |
2132 | } | |
2133 | ||
dec41e98 | 2134 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2135 | dump_cand (dump_file, cand); | |
2136 | } | |
2137 | ||
2138 | if (important && !cand->important) | |
2139 | { | |
2140 | cand->important = true; | |
2141 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2142 | fprintf (dump_file, "Candidate %d is important\n", cand->id); | |
2143 | } | |
2144 | ||
2145 | if (use) | |
2146 | { | |
2147 | bitmap_set_bit (use->related_cands, i); | |
2148 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2149 | fprintf (dump_file, "Candidate %d is related to use %d\n", | |
2150 | cand->id, use->id); | |
2151 | } | |
2152 | ||
2153 | return cand; | |
2154 | } | |
2155 | ||
5414270a | 2156 | /* Returns true if incrementing the induction variable at the end of the LOOP |
2157 | is allowed. | |
2158 | ||
2159 | The purpose is to avoid splitting latch edge with a biv increment, thus | |
2160 | creating a jump, possibly confusing other optimization passes and leaving | |
2161 | less freedom to scheduler. So we allow IP_END_POS only if IP_NORMAL_POS | |
2162 | is not available (so we do not have a better alternative), or if the latch | |
2163 | edge is already nonempty. */ | |
2164 | ||
2165 | static bool | |
2166 | allow_ip_end_pos_p (struct loop *loop) | |
2167 | { | |
2168 | if (!ip_normal_pos (loop)) | |
2169 | return true; | |
2170 | ||
2171 | if (!empty_block_p (ip_end_pos (loop))) | |
2172 | return true; | |
2173 | ||
2174 | return false; | |
2175 | } | |
2176 | ||
dec41e98 | 2177 | /* Adds a candidate BASE + STEP * i. Important field is set to IMPORTANT and |
2178 | position to POS. If USE is not NULL, the candidate is set as related to | |
2179 | it. The candidate computation is scheduled on all available positions. */ | |
2180 | ||
2181 | static void | |
2182 | add_candidate (struct ivopts_data *data, | |
2183 | tree base, tree step, bool important, struct iv_use *use) | |
2184 | { | |
2185 | if (ip_normal_pos (data->current_loop)) | |
75a70cf9 | 2186 | add_candidate_1 (data, base, step, important, IP_NORMAL, use, NULL); |
5414270a | 2187 | if (ip_end_pos (data->current_loop) |
2188 | && allow_ip_end_pos_p (data->current_loop)) | |
75a70cf9 | 2189 | add_candidate_1 (data, base, step, important, IP_END, use, NULL); |
dec41e98 | 2190 | } |
2191 | ||
3fd8a7ab | 2192 | /* Add a standard "0 + 1 * iteration" iv candidate for a |
2193 | type with SIZE bits. */ | |
2194 | ||
2195 | static void | |
2196 | add_standard_iv_candidates_for_size (struct ivopts_data *data, | |
2197 | unsigned int size) | |
2198 | { | |
2199 | tree type = lang_hooks.types.type_for_size (size, true); | |
2200 | add_candidate (data, build_int_cst (type, 0), build_int_cst (type, 1), | |
2201 | true, NULL); | |
2202 | } | |
2203 | ||
dec41e98 | 2204 | /* Adds standard iv candidates. */ |
2205 | ||
2206 | static void | |
2207 | add_standard_iv_candidates (struct ivopts_data *data) | |
2208 | { | |
3fd8a7ab | 2209 | add_standard_iv_candidates_for_size (data, INT_TYPE_SIZE); |
dec41e98 | 2210 | |
3fd8a7ab | 2211 | /* The same for a double-integer type if it is still fast enough. */ |
2212 | if (BITS_PER_WORD >= INT_TYPE_SIZE * 2) | |
2213 | add_standard_iv_candidates_for_size (data, INT_TYPE_SIZE * 2); | |
dec41e98 | 2214 | } |
2215 | ||
2216 | ||
2217 | /* Adds candidates bases on the old induction variable IV. */ | |
2218 | ||
2219 | static void | |
2220 | add_old_iv_candidates (struct ivopts_data *data, struct iv *iv) | |
2221 | { | |
75a70cf9 | 2222 | gimple phi; |
2223 | tree def; | |
dec41e98 | 2224 | struct iv_cand *cand; |
2225 | ||
2226 | add_candidate (data, iv->base, iv->step, true, NULL); | |
2227 | ||
2228 | /* The same, but with initial value zero. */ | |
19052ad2 | 2229 | if (POINTER_TYPE_P (TREE_TYPE (iv->base))) |
2230 | add_candidate (data, size_int (0), iv->step, true, NULL); | |
2231 | else | |
2232 | add_candidate (data, build_int_cst (TREE_TYPE (iv->base), 0), | |
2233 | iv->step, true, NULL); | |
dec41e98 | 2234 | |
2235 | phi = SSA_NAME_DEF_STMT (iv->ssa_name); | |
75a70cf9 | 2236 | if (gimple_code (phi) == GIMPLE_PHI) |
dec41e98 | 2237 | { |
2238 | /* Additionally record the possibility of leaving the original iv | |
2239 | untouched. */ | |
2240 | def = PHI_ARG_DEF_FROM_EDGE (phi, loop_latch_edge (data->current_loop)); | |
2241 | cand = add_candidate_1 (data, | |
2242 | iv->base, iv->step, true, IP_ORIGINAL, NULL, | |
2243 | SSA_NAME_DEF_STMT (def)); | |
2244 | cand->var_before = iv->ssa_name; | |
2245 | cand->var_after = def; | |
2246 | } | |
2247 | } | |
2248 | ||
2249 | /* Adds candidates based on the old induction variables. */ | |
2250 | ||
2251 | static void | |
2252 | add_old_ivs_candidates (struct ivopts_data *data) | |
2253 | { | |
2254 | unsigned i; | |
2255 | struct iv *iv; | |
0cc4271a | 2256 | bitmap_iterator bi; |
dec41e98 | 2257 | |
0cc4271a | 2258 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
dec41e98 | 2259 | { |
2260 | iv = ver_info (data, i)->iv; | |
7a973feb | 2261 | if (iv && iv->biv_p && !integer_zerop (iv->step)) |
dec41e98 | 2262 | add_old_iv_candidates (data, iv); |
0cc4271a | 2263 | } |
dec41e98 | 2264 | } |
2265 | ||
2266 | /* Adds candidates based on the value of the induction variable IV and USE. */ | |
2267 | ||
2268 | static void | |
2269 | add_iv_value_candidates (struct ivopts_data *data, | |
2270 | struct iv *iv, struct iv_use *use) | |
2271 | { | |
390955a6 | 2272 | unsigned HOST_WIDE_INT offset; |
651874e1 | 2273 | tree base; |
06240723 | 2274 | tree basetype; |
dec41e98 | 2275 | |
651874e1 | 2276 | add_candidate (data, iv->base, iv->step, false, use); |
a59824bb | 2277 | |
651874e1 | 2278 | /* The same, but with initial value zero. Make such variable important, |
2279 | since it is generic enough so that possibly many uses may be based | |
2280 | on it. */ | |
06240723 | 2281 | basetype = TREE_TYPE (iv->base); |
2282 | if (POINTER_TYPE_P (basetype)) | |
2283 | basetype = sizetype; | |
2284 | add_candidate (data, build_int_cst (basetype, 0), | |
651874e1 | 2285 | iv->step, true, use); |
dec41e98 | 2286 | |
0cfdcbde | 2287 | /* Third, try removing the constant offset. Make sure to even |
2288 | add a candidate for &a[0] vs. (T *)&a. */ | |
651874e1 | 2289 | base = strip_offset (iv->base, &offset); |
0cfdcbde | 2290 | if (offset |
2291 | || base != iv->base) | |
390955a6 | 2292 | add_candidate (data, base, iv->step, false, use); |
dec41e98 | 2293 | } |
2294 | ||
dec41e98 | 2295 | /* Adds candidates based on the uses. */ |
2296 | ||
2297 | static void | |
2298 | add_derived_ivs_candidates (struct ivopts_data *data) | |
2299 | { | |
2300 | unsigned i; | |
2301 | ||
2302 | for (i = 0; i < n_iv_uses (data); i++) | |
2303 | { | |
2304 | struct iv_use *use = iv_use (data, i); | |
2305 | ||
2306 | if (!use) | |
2307 | continue; | |
2308 | ||
2309 | switch (use->type) | |
2310 | { | |
2311 | case USE_NONLINEAR_EXPR: | |
2312 | case USE_COMPARE: | |
651874e1 | 2313 | case USE_ADDRESS: |
dec41e98 | 2314 | /* Just add the ivs based on the value of the iv used here. */ |
2315 | add_iv_value_candidates (data, use->iv, use); | |
2316 | break; | |
2317 | ||
dec41e98 | 2318 | default: |
8c0963c4 | 2319 | gcc_unreachable (); |
dec41e98 | 2320 | } |
2321 | } | |
2322 | } | |
2323 | ||
00991688 | 2324 | /* Record important candidates and add them to related_cands bitmaps |
2325 | if needed. */ | |
2326 | ||
2327 | static void | |
2328 | record_important_candidates (struct ivopts_data *data) | |
2329 | { | |
2330 | unsigned i; | |
2331 | struct iv_use *use; | |
2332 | ||
2333 | for (i = 0; i < n_iv_cands (data); i++) | |
2334 | { | |
2335 | struct iv_cand *cand = iv_cand (data, i); | |
2336 | ||
2337 | if (cand->important) | |
2338 | bitmap_set_bit (data->important_candidates, i); | |
2339 | } | |
2340 | ||
2341 | data->consider_all_candidates = (n_iv_cands (data) | |
2342 | <= CONSIDER_ALL_CANDIDATES_BOUND); | |
2343 | ||
2344 | if (data->consider_all_candidates) | |
2345 | { | |
2346 | /* We will not need "related_cands" bitmaps in this case, | |
2347 | so release them to decrease peak memory consumption. */ | |
2348 | for (i = 0; i < n_iv_uses (data); i++) | |
2349 | { | |
2350 | use = iv_use (data, i); | |
27335ffd | 2351 | BITMAP_FREE (use->related_cands); |
00991688 | 2352 | } |
2353 | } | |
2354 | else | |
2355 | { | |
2356 | /* Add important candidates to the related_cands bitmaps. */ | |
2357 | for (i = 0; i < n_iv_uses (data); i++) | |
2358 | bitmap_ior_into (iv_use (data, i)->related_cands, | |
2359 | data->important_candidates); | |
2360 | } | |
2361 | } | |
2362 | ||
dec41e98 | 2363 | /* Finds the candidates for the induction variables. */ |
2364 | ||
2365 | static void | |
2366 | find_iv_candidates (struct ivopts_data *data) | |
2367 | { | |
2368 | /* Add commonly used ivs. */ | |
2369 | add_standard_iv_candidates (data); | |
2370 | ||
2371 | /* Add old induction variables. */ | |
2372 | add_old_ivs_candidates (data); | |
2373 | ||
2374 | /* Add induction variables derived from uses. */ | |
2375 | add_derived_ivs_candidates (data); | |
00991688 | 2376 | |
2377 | /* Record the important candidates. */ | |
2378 | record_important_candidates (data); | |
dec41e98 | 2379 | } |
2380 | ||
2381 | /* Allocates the data structure mapping the (use, candidate) pairs to costs. | |
2382 | If consider_all_candidates is true, we use a two-dimensional array, otherwise | |
2383 | we allocate a simple list to every use. */ | |
2384 | ||
2385 | static void | |
2386 | alloc_use_cost_map (struct ivopts_data *data) | |
2387 | { | |
00991688 | 2388 | unsigned i, size, s, j; |
dec41e98 | 2389 | |
2390 | for (i = 0; i < n_iv_uses (data); i++) | |
2391 | { | |
2392 | struct iv_use *use = iv_use (data, i); | |
0cc4271a | 2393 | bitmap_iterator bi; |
dec41e98 | 2394 | |
2395 | if (data->consider_all_candidates) | |
00991688 | 2396 | size = n_iv_cands (data); |
dec41e98 | 2397 | else |
2398 | { | |
00991688 | 2399 | s = 0; |
0cc4271a | 2400 | EXECUTE_IF_SET_IN_BITMAP (use->related_cands, 0, j, bi) |
2401 | { | |
00991688 | 2402 | s++; |
0cc4271a | 2403 | } |
00991688 | 2404 | |
2405 | /* Round up to the power of two, so that moduling by it is fast. */ | |
2406 | for (size = 1; size < s; size <<= 1) | |
2407 | continue; | |
dec41e98 | 2408 | } |
2409 | ||
00991688 | 2410 | use->n_map_members = size; |
4c36ffe6 | 2411 | use->cost_map = XCNEWVEC (struct cost_pair, size); |
dec41e98 | 2412 | } |
2413 | } | |
2414 | ||
3c2818b0 | 2415 | /* Returns description of computation cost of expression whose runtime |
2416 | cost is RUNTIME and complexity corresponds to COMPLEXITY. */ | |
2417 | ||
2418 | static comp_cost | |
2419 | new_cost (unsigned runtime, unsigned complexity) | |
2420 | { | |
2421 | comp_cost cost; | |
2422 | ||
2423 | cost.cost = runtime; | |
2424 | cost.complexity = complexity; | |
2425 | ||
2426 | return cost; | |
2427 | } | |
2428 | ||
2429 | /* Adds costs COST1 and COST2. */ | |
2430 | ||
2431 | static comp_cost | |
2432 | add_costs (comp_cost cost1, comp_cost cost2) | |
2433 | { | |
2434 | cost1.cost += cost2.cost; | |
2435 | cost1.complexity += cost2.complexity; | |
2436 | ||
2437 | return cost1; | |
2438 | } | |
2439 | /* Subtracts costs COST1 and COST2. */ | |
2440 | ||
2441 | static comp_cost | |
2442 | sub_costs (comp_cost cost1, comp_cost cost2) | |
2443 | { | |
2444 | cost1.cost -= cost2.cost; | |
2445 | cost1.complexity -= cost2.complexity; | |
2446 | ||
2447 | return cost1; | |
2448 | } | |
2449 | ||
2450 | /* Returns a negative number if COST1 < COST2, a positive number if | |
2451 | COST1 > COST2, and 0 if COST1 = COST2. */ | |
2452 | ||
2453 | static int | |
2454 | compare_costs (comp_cost cost1, comp_cost cost2) | |
2455 | { | |
2456 | if (cost1.cost == cost2.cost) | |
2457 | return cost1.complexity - cost2.complexity; | |
2458 | ||
2459 | return cost1.cost - cost2.cost; | |
2460 | } | |
2461 | ||
2462 | /* Returns true if COST is infinite. */ | |
2463 | ||
2464 | static bool | |
2465 | infinite_cost_p (comp_cost cost) | |
2466 | { | |
2467 | return cost.cost == INFTY; | |
2468 | } | |
2469 | ||
dec41e98 | 2470 | /* Sets cost of (USE, CANDIDATE) pair to COST and record that it depends |
c4d3b428 | 2471 | on invariants DEPENDS_ON and that the value used in expressing it |
2472 | is VALUE.*/ | |
dec41e98 | 2473 | |
2474 | static void | |
2475 | set_use_iv_cost (struct ivopts_data *data, | |
3c2818b0 | 2476 | struct iv_use *use, struct iv_cand *cand, |
2477 | comp_cost cost, bitmap depends_on, tree value) | |
dec41e98 | 2478 | { |
00991688 | 2479 | unsigned i, s; |
2480 | ||
3c2818b0 | 2481 | if (infinite_cost_p (cost)) |
dec41e98 | 2482 | { |
27335ffd | 2483 | BITMAP_FREE (depends_on); |
00991688 | 2484 | return; |
dec41e98 | 2485 | } |
2486 | ||
2487 | if (data->consider_all_candidates) | |
2488 | { | |
2489 | use->cost_map[cand->id].cand = cand; | |
2490 | use->cost_map[cand->id].cost = cost; | |
2491 | use->cost_map[cand->id].depends_on = depends_on; | |
c4d3b428 | 2492 | use->cost_map[cand->id].value = value; |
dec41e98 | 2493 | return; |
2494 | } | |
2495 | ||
00991688 | 2496 | /* n_map_members is a power of two, so this computes modulo. */ |
2497 | s = cand->id & (use->n_map_members - 1); | |
2498 | for (i = s; i < use->n_map_members; i++) | |
2499 | if (!use->cost_map[i].cand) | |
2500 | goto found; | |
2501 | for (i = 0; i < s; i++) | |
2502 | if (!use->cost_map[i].cand) | |
2503 | goto found; | |
2504 | ||
2505 | gcc_unreachable (); | |
dec41e98 | 2506 | |
00991688 | 2507 | found: |
2508 | use->cost_map[i].cand = cand; | |
2509 | use->cost_map[i].cost = cost; | |
2510 | use->cost_map[i].depends_on = depends_on; | |
c4d3b428 | 2511 | use->cost_map[i].value = value; |
dec41e98 | 2512 | } |
2513 | ||
00991688 | 2514 | /* Gets cost of (USE, CANDIDATE) pair. */ |
dec41e98 | 2515 | |
00991688 | 2516 | static struct cost_pair * |
2517 | get_use_iv_cost (struct ivopts_data *data, struct iv_use *use, | |
2518 | struct iv_cand *cand) | |
dec41e98 | 2519 | { |
00991688 | 2520 | unsigned i, s; |
2521 | struct cost_pair *ret; | |
dec41e98 | 2522 | |
2523 | if (!cand) | |
00991688 | 2524 | return NULL; |
dec41e98 | 2525 | |
2526 | if (data->consider_all_candidates) | |
dec41e98 | 2527 | { |
00991688 | 2528 | ret = use->cost_map + cand->id; |
2529 | if (!ret->cand) | |
2530 | return NULL; | |
dec41e98 | 2531 | |
00991688 | 2532 | return ret; |
dec41e98 | 2533 | } |
00991688 | 2534 | |
2535 | /* n_map_members is a power of two, so this computes modulo. */ | |
2536 | s = cand->id & (use->n_map_members - 1); | |
2537 | for (i = s; i < use->n_map_members; i++) | |
2538 | if (use->cost_map[i].cand == cand) | |
2539 | return use->cost_map + i; | |
dec41e98 | 2540 | |
00991688 | 2541 | for (i = 0; i < s; i++) |
2542 | if (use->cost_map[i].cand == cand) | |
2543 | return use->cost_map + i; | |
2544 | ||
2545 | return NULL; | |
dec41e98 | 2546 | } |
2547 | ||
2548 | /* Returns estimate on cost of computing SEQ. */ | |
2549 | ||
2550 | static unsigned | |
f529eb25 | 2551 | seq_cost (rtx seq, bool speed) |
dec41e98 | 2552 | { |
2553 | unsigned cost = 0; | |
2554 | rtx set; | |
2555 | ||
2556 | for (; seq; seq = NEXT_INSN (seq)) | |
2557 | { | |
2558 | set = single_set (seq); | |
2559 | if (set) | |
f529eb25 | 2560 | cost += rtx_cost (set, SET,speed); |
dec41e98 | 2561 | else |
2562 | cost++; | |
2563 | } | |
2564 | ||
2565 | return cost; | |
2566 | } | |
2567 | ||
abf7e53a | 2568 | /* Produce DECL_RTL for object obj so it looks like it is stored in memory. */ |
2569 | static rtx | |
2570 | produce_memory_decl_rtl (tree obj, int *regno) | |
2571 | { | |
2572 | rtx x; | |
876760f6 | 2573 | |
2574 | gcc_assert (obj); | |
abf7e53a | 2575 | if (TREE_STATIC (obj) || DECL_EXTERNAL (obj)) |
2576 | { | |
2577 | const char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (obj)); | |
2578 | x = gen_rtx_SYMBOL_REF (Pmode, name); | |
7e995af7 | 2579 | SET_SYMBOL_REF_DECL (x, obj); |
2580 | x = gen_rtx_MEM (DECL_MODE (obj), x); | |
2581 | targetm.encode_section_info (obj, x, true); | |
abf7e53a | 2582 | } |
2583 | else | |
7e995af7 | 2584 | { |
2585 | x = gen_raw_REG (Pmode, (*regno)++); | |
2586 | x = gen_rtx_MEM (DECL_MODE (obj), x); | |
2587 | } | |
abf7e53a | 2588 | |
7e995af7 | 2589 | return x; |
abf7e53a | 2590 | } |
2591 | ||
dec41e98 | 2592 | /* Prepares decl_rtl for variables referred in *EXPR_P. Callback for |
2593 | walk_tree. DATA contains the actual fake register number. */ | |
2594 | ||
2595 | static tree | |
2596 | prepare_decl_rtl (tree *expr_p, int *ws, void *data) | |
2597 | { | |
2598 | tree obj = NULL_TREE; | |
2599 | rtx x = NULL_RTX; | |
f0d6e81c | 2600 | int *regno = (int *) data; |
dec41e98 | 2601 | |
2602 | switch (TREE_CODE (*expr_p)) | |
2603 | { | |
abf7e53a | 2604 | case ADDR_EXPR: |
2605 | for (expr_p = &TREE_OPERAND (*expr_p, 0); | |
1f9b622b | 2606 | handled_component_p (*expr_p); |
2607 | expr_p = &TREE_OPERAND (*expr_p, 0)) | |
2608 | continue; | |
abf7e53a | 2609 | obj = *expr_p; |
f2d0e9f1 | 2610 | if (DECL_P (obj) && !DECL_RTL_SET_P (obj)) |
abf7e53a | 2611 | x = produce_memory_decl_rtl (obj, regno); |
2612 | break; | |
2613 | ||
dec41e98 | 2614 | case SSA_NAME: |
2615 | *ws = 0; | |
2616 | obj = SSA_NAME_VAR (*expr_p); | |
2617 | if (!DECL_RTL_SET_P (obj)) | |
2618 | x = gen_raw_REG (DECL_MODE (obj), (*regno)++); | |
2619 | break; | |
2620 | ||
2621 | case VAR_DECL: | |
2622 | case PARM_DECL: | |
2623 | case RESULT_DECL: | |
2624 | *ws = 0; | |
2625 | obj = *expr_p; | |
2626 | ||
2627 | if (DECL_RTL_SET_P (obj)) | |
2628 | break; | |
2629 | ||
2630 | if (DECL_MODE (obj) == BLKmode) | |
abf7e53a | 2631 | x = produce_memory_decl_rtl (obj, regno); |
dec41e98 | 2632 | else |
2633 | x = gen_raw_REG (DECL_MODE (obj), (*regno)++); | |
2634 | ||
2635 | break; | |
2636 | ||
2637 | default: | |
2638 | break; | |
2639 | } | |
2640 | ||
2641 | if (x) | |
2642 | { | |
7d18ea07 | 2643 | VEC_safe_push (tree, heap, decl_rtl_to_reset, obj); |
dec41e98 | 2644 | SET_DECL_RTL (obj, x); |
2645 | } | |
2646 | ||
2647 | return NULL_TREE; | |
2648 | } | |
2649 | ||
2650 | /* Determines cost of the computation of EXPR. */ | |
2651 | ||
2652 | static unsigned | |
f529eb25 | 2653 | computation_cost (tree expr, bool speed) |
dec41e98 | 2654 | { |
2655 | rtx seq, rslt; | |
2656 | tree type = TREE_TYPE (expr); | |
2657 | unsigned cost; | |
15a79151 | 2658 | /* Avoid using hard regs in ways which may be unsupported. */ |
2659 | int regno = LAST_VIRTUAL_REGISTER + 1; | |
f529eb25 | 2660 | enum function_frequency real_frequency = cfun->function_frequency; |
dec41e98 | 2661 | |
f529eb25 | 2662 | cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL; |
2663 | crtl->maybe_hot_insn_p = speed; | |
dec41e98 | 2664 | walk_tree (&expr, prepare_decl_rtl, ®no, NULL); |
2665 | start_sequence (); | |
2666 | rslt = expand_expr (expr, NULL_RTX, TYPE_MODE (type), EXPAND_NORMAL); | |
2667 | seq = get_insns (); | |
2668 | end_sequence (); | |
f529eb25 | 2669 | default_rtl_profile (); |
2670 | cfun->function_frequency = real_frequency; | |
dec41e98 | 2671 | |
f529eb25 | 2672 | cost = seq_cost (seq, speed); |
1c14a50e | 2673 | if (MEM_P (rslt)) |
f529eb25 | 2674 | cost += address_cost (XEXP (rslt, 0), TYPE_MODE (type), speed); |
dec41e98 | 2675 | |
2676 | return cost; | |
2677 | } | |
2678 | ||
2679 | /* Returns variable containing the value of candidate CAND at statement AT. */ | |
2680 | ||
2681 | static tree | |
75a70cf9 | 2682 | var_at_stmt (struct loop *loop, struct iv_cand *cand, gimple stmt) |
dec41e98 | 2683 | { |
2684 | if (stmt_after_increment (loop, cand, stmt)) | |
2685 | return cand->var_after; | |
2686 | else | |
2687 | return cand->var_before; | |
2688 | } | |
2689 | ||
651874e1 | 2690 | /* Return the most significant (sign) bit of T. Similar to tree_int_cst_msb, |
2691 | but the bit is determined from TYPE_PRECISION, not MODE_BITSIZE. */ | |
2692 | ||
b9845e76 | 2693 | int |
b7bf20db | 2694 | tree_int_cst_sign_bit (const_tree t) |
651874e1 | 2695 | { |
2696 | unsigned bitno = TYPE_PRECISION (TREE_TYPE (t)) - 1; | |
2697 | unsigned HOST_WIDE_INT w; | |
2698 | ||
2699 | if (bitno < HOST_BITS_PER_WIDE_INT) | |
2700 | w = TREE_INT_CST_LOW (t); | |
2701 | else | |
2702 | { | |
2703 | w = TREE_INT_CST_HIGH (t); | |
2704 | bitno -= HOST_BITS_PER_WIDE_INT; | |
2705 | } | |
2706 | ||
2707 | return (w >> bitno) & 1; | |
2708 | } | |
2709 | ||
4d9f13e4 | 2710 | /* If A is (TYPE) BA and B is (TYPE) BB, and the types of BA and BB have the |
2711 | same precision that is at least as wide as the precision of TYPE, stores | |
2712 | BA to A and BB to B, and returns the type of BA. Otherwise, returns the | |
2713 | type of A and B. */ | |
2714 | ||
2715 | static tree | |
2716 | determine_common_wider_type (tree *a, tree *b) | |
2717 | { | |
2718 | tree wider_type = NULL; | |
2719 | tree suba, subb; | |
2720 | tree atype = TREE_TYPE (*a); | |
2721 | ||
72dd6141 | 2722 | if (CONVERT_EXPR_P (*a)) |
4d9f13e4 | 2723 | { |
2724 | suba = TREE_OPERAND (*a, 0); | |
2725 | wider_type = TREE_TYPE (suba); | |
2726 | if (TYPE_PRECISION (wider_type) < TYPE_PRECISION (atype)) | |
2727 | return atype; | |
2728 | } | |
2729 | else | |
2730 | return atype; | |
2731 | ||
72dd6141 | 2732 | if (CONVERT_EXPR_P (*b)) |
4d9f13e4 | 2733 | { |
2734 | subb = TREE_OPERAND (*b, 0); | |
2735 | if (TYPE_PRECISION (wider_type) != TYPE_PRECISION (TREE_TYPE (subb))) | |
2736 | return atype; | |
2737 | } | |
2738 | else | |
2739 | return atype; | |
2740 | ||
2741 | *a = suba; | |
2742 | *b = subb; | |
2743 | return wider_type; | |
2744 | } | |
2745 | ||
dec41e98 | 2746 | /* Determines the expression by that USE is expressed from induction variable |
aed164c3 | 2747 | CAND at statement AT in LOOP. The expression is stored in a decomposed |
2748 | form into AFF. Returns false if USE cannot be expressed using CAND. */ | |
dec41e98 | 2749 | |
aed164c3 | 2750 | static bool |
2751 | get_computation_aff (struct loop *loop, | |
75a70cf9 | 2752 | struct iv_use *use, struct iv_cand *cand, gimple at, |
aed164c3 | 2753 | struct affine_tree_combination *aff) |
dec41e98 | 2754 | { |
dbc64c75 | 2755 | tree ubase = use->iv->base; |
2756 | tree ustep = use->iv->step; | |
2757 | tree cbase = cand->iv->base; | |
d3610bea | 2758 | tree cstep = cand->iv->step, cstep_common; |
dec41e98 | 2759 | tree utype = TREE_TYPE (ubase), ctype = TREE_TYPE (cbase); |
d3610bea | 2760 | tree common_type, var; |
dec41e98 | 2761 | tree uutype; |
d3610bea | 2762 | aff_tree cbase_aff, var_aff; |
58f43b90 | 2763 | double_int rat; |
dec41e98 | 2764 | |
2765 | if (TYPE_PRECISION (utype) > TYPE_PRECISION (ctype)) | |
2766 | { | |
2767 | /* We do not have a precision to express the values of use. */ | |
aed164c3 | 2768 | return false; |
dec41e98 | 2769 | } |
2770 | ||
d3610bea | 2771 | var = var_at_stmt (loop, cand, at); |
2772 | uutype = unsigned_type_for (utype); | |
dec41e98 | 2773 | |
d3610bea | 2774 | /* If the conversion is not noop, perform it. */ |
2775 | if (TYPE_PRECISION (utype) < TYPE_PRECISION (ctype)) | |
dec41e98 | 2776 | { |
dec41e98 | 2777 | cstep = fold_convert (uutype, cstep); |
d3610bea | 2778 | cbase = fold_convert (uutype, cbase); |
2779 | var = fold_convert (uutype, var); | |
651874e1 | 2780 | } |
651874e1 | 2781 | |
d3610bea | 2782 | if (!constant_multiple_of (ustep, cstep, &rat)) |
2783 | return false; | |
dec41e98 | 2784 | |
4d9f13e4 | 2785 | /* In case both UBASE and CBASE are shortened to UUTYPE from some common |
2786 | type, we achieve better folding by computing their difference in this | |
2787 | wider type, and cast the result to UUTYPE. We do not need to worry about | |
2788 | overflows, as all the arithmetics will in the end be performed in UUTYPE | |
2789 | anyway. */ | |
2790 | common_type = determine_common_wider_type (&ubase, &cbase); | |
2791 | ||
d3610bea | 2792 | /* use = ubase - ratio * cbase + ratio * var. */ |
2793 | tree_to_aff_combination (ubase, common_type, aff); | |
2794 | tree_to_aff_combination (cbase, common_type, &cbase_aff); | |
2795 | tree_to_aff_combination (var, uutype, &var_aff); | |
dec41e98 | 2796 | |
d3610bea | 2797 | /* We need to shift the value if we are after the increment. */ |
2798 | if (stmt_after_increment (loop, cand, at)) | |
dec41e98 | 2799 | { |
d3610bea | 2800 | aff_tree cstep_aff; |
2801 | ||
2802 | if (common_type != uutype) | |
2803 | cstep_common = fold_convert (common_type, cstep); | |
651874e1 | 2804 | else |
d3610bea | 2805 | cstep_common = cstep; |
aed164c3 | 2806 | |
d3610bea | 2807 | tree_to_aff_combination (cstep_common, common_type, &cstep_aff); |
2808 | aff_combination_add (&cbase_aff, &cstep_aff); | |
dec41e98 | 2809 | } |
dec41e98 | 2810 | |
d3610bea | 2811 | aff_combination_scale (&cbase_aff, double_int_neg (rat)); |
aed164c3 | 2812 | aff_combination_add (aff, &cbase_aff); |
4d9f13e4 | 2813 | if (common_type != uutype) |
d3610bea | 2814 | aff_combination_convert (aff, uutype); |
2815 | ||
2816 | aff_combination_scale (&var_aff, rat); | |
2817 | aff_combination_add (aff, &var_aff); | |
aed164c3 | 2818 | |
2819 | return true; | |
2820 | } | |
2821 | ||
2822 | /* Determines the expression by that USE is expressed from induction variable | |
2823 | CAND at statement AT in LOOP. The computation is unshared. */ | |
2824 | ||
2825 | static tree | |
2826 | get_computation_at (struct loop *loop, | |
75a70cf9 | 2827 | struct iv_use *use, struct iv_cand *cand, gimple at) |
aed164c3 | 2828 | { |
d3610bea | 2829 | aff_tree aff; |
aed164c3 | 2830 | tree type = TREE_TYPE (use->iv->base); |
2831 | ||
2832 | if (!get_computation_aff (loop, use, cand, at, &aff)) | |
2833 | return NULL_TREE; | |
2834 | unshare_aff_combination (&aff); | |
2835 | return fold_convert (type, aff_combination_to_tree (&aff)); | |
dec41e98 | 2836 | } |
2837 | ||
2838 | /* Determines the expression by that USE is expressed from induction variable | |
aed164c3 | 2839 | CAND in LOOP. The computation is unshared. */ |
dec41e98 | 2840 | |
2841 | static tree | |
2842 | get_computation (struct loop *loop, struct iv_use *use, struct iv_cand *cand) | |
2843 | { | |
2844 | return get_computation_at (loop, use, cand, use->stmt); | |
2845 | } | |
2846 | ||
dec41e98 | 2847 | /* Returns cost of addition in MODE. */ |
2848 | ||
2849 | static unsigned | |
f529eb25 | 2850 | add_cost (enum machine_mode mode, bool speed) |
dec41e98 | 2851 | { |
2852 | static unsigned costs[NUM_MACHINE_MODES]; | |
2853 | rtx seq; | |
2854 | unsigned cost; | |
2855 | ||
2856 | if (costs[mode]) | |
2857 | return costs[mode]; | |
2858 | ||
2859 | start_sequence (); | |
2860 | force_operand (gen_rtx_fmt_ee (PLUS, mode, | |
5bf0af5e | 2861 | gen_raw_REG (mode, LAST_VIRTUAL_REGISTER + 1), |
2862 | gen_raw_REG (mode, LAST_VIRTUAL_REGISTER + 2)), | |
dec41e98 | 2863 | NULL_RTX); |
2864 | seq = get_insns (); | |
2865 | end_sequence (); | |
2866 | ||
f529eb25 | 2867 | cost = seq_cost (seq, speed); |
dec41e98 | 2868 | if (!cost) |
2869 | cost = 1; | |
2870 | ||
2871 | costs[mode] = cost; | |
2872 | ||
2873 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2874 | fprintf (dump_file, "Addition in %s costs %d\n", | |
2875 | GET_MODE_NAME (mode), cost); | |
2876 | return cost; | |
2877 | } | |
2878 | ||
2879 | /* Entry in a hashtable of already known costs for multiplication. */ | |
2880 | struct mbc_entry | |
2881 | { | |
2882 | HOST_WIDE_INT cst; /* The constant to multiply by. */ | |
2883 | enum machine_mode mode; /* In mode. */ | |
2884 | unsigned cost; /* The cost. */ | |
2885 | }; | |
2886 | ||
2887 | /* Counts hash value for the ENTRY. */ | |
2888 | ||
2889 | static hashval_t | |
2890 | mbc_entry_hash (const void *entry) | |
2891 | { | |
f0d6e81c | 2892 | const struct mbc_entry *e = (const struct mbc_entry *) entry; |
dec41e98 | 2893 | |
2894 | return 57 * (hashval_t) e->mode + (hashval_t) (e->cst % 877); | |
2895 | } | |
2896 | ||
2897 | /* Compares the hash table entries ENTRY1 and ENTRY2. */ | |
2898 | ||
2899 | static int | |
2900 | mbc_entry_eq (const void *entry1, const void *entry2) | |
2901 | { | |
f0d6e81c | 2902 | const struct mbc_entry *e1 = (const struct mbc_entry *) entry1; |
2903 | const struct mbc_entry *e2 = (const struct mbc_entry *) entry2; | |
dec41e98 | 2904 | |
2905 | return (e1->mode == e2->mode | |
2906 | && e1->cst == e2->cst); | |
2907 | } | |
2908 | ||
2909 | /* Returns cost of multiplication by constant CST in MODE. */ | |
2910 | ||
aed164c3 | 2911 | unsigned |
f529eb25 | 2912 | multiply_by_cost (HOST_WIDE_INT cst, enum machine_mode mode, bool speed) |
dec41e98 | 2913 | { |
2914 | static htab_t costs; | |
2915 | struct mbc_entry **cached, act; | |
2916 | rtx seq; | |
2917 | unsigned cost; | |
2918 | ||
2919 | if (!costs) | |
2920 | costs = htab_create (100, mbc_entry_hash, mbc_entry_eq, free); | |
2921 | ||
2922 | act.mode = mode; | |
2923 | act.cst = cst; | |
2924 | cached = (struct mbc_entry **) htab_find_slot (costs, &act, INSERT); | |
2925 | if (*cached) | |
2926 | return (*cached)->cost; | |
2927 | ||
4c36ffe6 | 2928 | *cached = XNEW (struct mbc_entry); |
dec41e98 | 2929 | (*cached)->mode = mode; |
2930 | (*cached)->cst = cst; | |
2931 | ||
2932 | start_sequence (); | |
5bf0af5e | 2933 | expand_mult (mode, gen_raw_REG (mode, LAST_VIRTUAL_REGISTER + 1), |
2934 | gen_int_mode (cst, mode), NULL_RTX, 0); | |
dec41e98 | 2935 | seq = get_insns (); |
2936 | end_sequence (); | |
2937 | ||
f529eb25 | 2938 | cost = seq_cost (seq, speed); |
dec41e98 | 2939 | |
2940 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2941 | fprintf (dump_file, "Multiplication by %d in %s costs %d\n", | |
2942 | (int) cst, GET_MODE_NAME (mode), cost); | |
2943 | ||
2944 | (*cached)->cost = cost; | |
2945 | ||
2946 | return cost; | |
2947 | } | |
2948 | ||
e90b35db | 2949 | /* Returns true if multiplying by RATIO is allowed in an address. Test the |
2950 | validity for a memory reference accessing memory of mode MODE. */ | |
aed164c3 | 2951 | |
2952 | bool | |
e7f482a0 | 2953 | multiplier_allowed_in_address_p (HOST_WIDE_INT ratio, enum machine_mode mode) |
aed164c3 | 2954 | { |
2955 | #define MAX_RATIO 128 | |
e7f482a0 | 2956 | static sbitmap valid_mult[MAX_MACHINE_MODE]; |
aed164c3 | 2957 | |
e7f482a0 | 2958 | if (!valid_mult[mode]) |
aed164c3 | 2959 | { |
5bf0af5e | 2960 | rtx reg1 = gen_raw_REG (Pmode, LAST_VIRTUAL_REGISTER + 1); |
aed164c3 | 2961 | rtx addr; |
2962 | HOST_WIDE_INT i; | |
2963 | ||
e7f482a0 | 2964 | valid_mult[mode] = sbitmap_alloc (2 * MAX_RATIO + 1); |
2965 | sbitmap_zero (valid_mult[mode]); | |
aed164c3 | 2966 | addr = gen_rtx_fmt_ee (MULT, Pmode, reg1, NULL_RTX); |
2967 | for (i = -MAX_RATIO; i <= MAX_RATIO; i++) | |
2968 | { | |
2969 | XEXP (addr, 1) = gen_int_mode (i, Pmode); | |
e7f482a0 | 2970 | if (memory_address_p (mode, addr)) |
2971 | SET_BIT (valid_mult[mode], i + MAX_RATIO); | |
aed164c3 | 2972 | } |
2973 | ||
2974 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2975 | { | |
2976 | fprintf (dump_file, " allowed multipliers:"); | |
2977 | for (i = -MAX_RATIO; i <= MAX_RATIO; i++) | |
e7f482a0 | 2978 | if (TEST_BIT (valid_mult[mode], i + MAX_RATIO)) |
aed164c3 | 2979 | fprintf (dump_file, " %d", (int) i); |
2980 | fprintf (dump_file, "\n"); | |
2981 | fprintf (dump_file, "\n"); | |
2982 | } | |
2983 | } | |
2984 | ||
2985 | if (ratio > MAX_RATIO || ratio < -MAX_RATIO) | |
2986 | return false; | |
2987 | ||
e7f482a0 | 2988 | return TEST_BIT (valid_mult[mode], ratio + MAX_RATIO); |
aed164c3 | 2989 | } |
2990 | ||
dec41e98 | 2991 | /* Returns cost of address in shape symbol + var + OFFSET + RATIO * index. |
2992 | If SYMBOL_PRESENT is false, symbol is omitted. If VAR_PRESENT is false, | |
e90b35db | 2993 | variable is omitted. Compute the cost for a memory reference that accesses |
2994 | a memory location of mode MEM_MODE. | |
2995 | ||
dec41e98 | 2996 | TODO -- there must be some better way. This all is quite crude. */ |
2997 | ||
3c2818b0 | 2998 | static comp_cost |
dec41e98 | 2999 | get_address_cost (bool symbol_present, bool var_present, |
e7f482a0 | 3000 | unsigned HOST_WIDE_INT offset, HOST_WIDE_INT ratio, |
f529eb25 | 3001 | enum machine_mode mem_mode, |
3002 | bool speed) | |
dec41e98 | 3003 | { |
e7f482a0 | 3004 | static bool initialized[MAX_MACHINE_MODE]; |
3005 | static HOST_WIDE_INT rat[MAX_MACHINE_MODE], off[MAX_MACHINE_MODE]; | |
3006 | static HOST_WIDE_INT min_offset[MAX_MACHINE_MODE], max_offset[MAX_MACHINE_MODE]; | |
3007 | static unsigned costs[MAX_MACHINE_MODE][2][2][2][2]; | |
3c2818b0 | 3008 | unsigned cost, acost, complexity; |
dec41e98 | 3009 | bool offset_p, ratio_p; |
dec41e98 | 3010 | HOST_WIDE_INT s_offset; |
3011 | unsigned HOST_WIDE_INT mask; | |
3012 | unsigned bits; | |
3013 | ||
e7f482a0 | 3014 | if (!initialized[mem_mode]) |
dec41e98 | 3015 | { |
3016 | HOST_WIDE_INT i; | |
e90b35db | 3017 | HOST_WIDE_INT start = BIGGEST_ALIGNMENT / BITS_PER_UNIT; |
9b6564b5 | 3018 | int old_cse_not_expected; |
3019 | unsigned sym_p, var_p, off_p, rat_p, add_c; | |
3020 | rtx seq, addr, base; | |
3021 | rtx reg0, reg1; | |
3022 | ||
e7f482a0 | 3023 | initialized[mem_mode] = true; |
dec41e98 | 3024 | |
5bf0af5e | 3025 | reg1 = gen_raw_REG (Pmode, LAST_VIRTUAL_REGISTER + 1); |
dec41e98 | 3026 | |
3027 | addr = gen_rtx_fmt_ee (PLUS, Pmode, reg1, NULL_RTX); | |
e90b35db | 3028 | for (i = start; i <= 1 << 20; i <<= 1) |
dec41e98 | 3029 | { |
5bf0af5e | 3030 | XEXP (addr, 1) = gen_int_mode (i, Pmode); |
e7f482a0 | 3031 | if (!memory_address_p (mem_mode, addr)) |
dec41e98 | 3032 | break; |
3033 | } | |
e90b35db | 3034 | max_offset[mem_mode] = i == start ? 0 : i >> 1; |
e7f482a0 | 3035 | off[mem_mode] = max_offset[mem_mode]; |
dec41e98 | 3036 | |
e90b35db | 3037 | for (i = start; i <= 1 << 20; i <<= 1) |
dec41e98 | 3038 | { |
5bf0af5e | 3039 | XEXP (addr, 1) = gen_int_mode (-i, Pmode); |
e7f482a0 | 3040 | if (!memory_address_p (mem_mode, addr)) |
dec41e98 | 3041 | break; |
3042 | } | |
e90b35db | 3043 | min_offset[mem_mode] = i == start ? 0 : -(i >> 1); |
dec41e98 | 3044 | |
3045 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3046 | { | |
3047 | fprintf (dump_file, "get_address_cost:\n"); | |
e7f482a0 | 3048 | fprintf (dump_file, " min offset %s %d\n", |
3049 | GET_MODE_NAME (mem_mode), | |
3050 | (int) min_offset[mem_mode]); | |
3051 | fprintf (dump_file, " max offset %s %d\n", | |
3052 | GET_MODE_NAME (mem_mode), | |
3053 | (int) max_offset[mem_mode]); | |
dec41e98 | 3054 | } |
3055 | ||
e7f482a0 | 3056 | rat[mem_mode] = 1; |
aed164c3 | 3057 | for (i = 2; i <= MAX_RATIO; i++) |
e7f482a0 | 3058 | if (multiplier_allowed_in_address_p (i, mem_mode)) |
aed164c3 | 3059 | { |
e7f482a0 | 3060 | rat[mem_mode] = i; |
aed164c3 | 3061 | break; |
3062 | } | |
9b6564b5 | 3063 | |
3064 | /* Compute the cost of various addressing modes. */ | |
3065 | acost = 0; | |
3066 | reg0 = gen_raw_REG (Pmode, LAST_VIRTUAL_REGISTER + 1); | |
3067 | reg1 = gen_raw_REG (Pmode, LAST_VIRTUAL_REGISTER + 2); | |
3068 | ||
3069 | for (i = 0; i < 16; i++) | |
3070 | { | |
3071 | sym_p = i & 1; | |
3072 | var_p = (i >> 1) & 1; | |
3073 | off_p = (i >> 2) & 1; | |
3074 | rat_p = (i >> 3) & 1; | |
3075 | ||
3076 | addr = reg0; | |
3077 | if (rat_p) | |
e7f482a0 | 3078 | addr = gen_rtx_fmt_ee (MULT, Pmode, addr, |
3079 | gen_int_mode (rat[mem_mode], Pmode)); | |
9b6564b5 | 3080 | |
3081 | if (var_p) | |
3082 | addr = gen_rtx_fmt_ee (PLUS, Pmode, addr, reg1); | |
3083 | ||
3084 | if (sym_p) | |
3085 | { | |
3086 | base = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup ("")); | |
7e995af7 | 3087 | /* ??? We can run into trouble with some backends by presenting |
f0b5f617 | 3088 | it with symbols which haven't been properly passed through |
7e995af7 | 3089 | targetm.encode_section_info. By setting the local bit, we |
3090 | enhance the probability of things working. */ | |
3091 | SYMBOL_REF_FLAGS (base) = SYMBOL_FLAG_LOCAL; | |
3092 | ||
9b6564b5 | 3093 | if (off_p) |
3094 | base = gen_rtx_fmt_e (CONST, Pmode, | |
3095 | gen_rtx_fmt_ee (PLUS, Pmode, | |
3096 | base, | |
e7f482a0 | 3097 | gen_int_mode (off[mem_mode], |
3098 | Pmode))); | |
9b6564b5 | 3099 | } |
3100 | else if (off_p) | |
e7f482a0 | 3101 | base = gen_int_mode (off[mem_mode], Pmode); |
9b6564b5 | 3102 | else |
3103 | base = NULL_RTX; | |
3104 | ||
3105 | if (base) | |
3106 | addr = gen_rtx_fmt_ee (PLUS, Pmode, addr, base); | |
3107 | ||
3108 | start_sequence (); | |
3109 | /* To avoid splitting addressing modes, pretend that no cse will | |
3110 | follow. */ | |
3111 | old_cse_not_expected = cse_not_expected; | |
3112 | cse_not_expected = true; | |
e7f482a0 | 3113 | addr = memory_address (mem_mode, addr); |
9b6564b5 | 3114 | cse_not_expected = old_cse_not_expected; |
3115 | seq = get_insns (); | |
3116 | end_sequence (); | |
3117 | ||
f529eb25 | 3118 | acost = seq_cost (seq, speed); |
3119 | acost += address_cost (addr, mem_mode, speed); | |
9b6564b5 | 3120 | |
3121 | if (!acost) | |
3122 | acost = 1; | |
e7f482a0 | 3123 | costs[mem_mode][sym_p][var_p][off_p][rat_p] = acost; |
9b6564b5 | 3124 | } |
3125 | ||
3126 | /* On some targets, it is quite expensive to load symbol to a register, | |
3127 | which makes addresses that contain symbols look much more expensive. | |
3128 | However, the symbol will have to be loaded in any case before the | |
3129 | loop (and quite likely we have it in register already), so it does not | |
3130 | make much sense to penalize them too heavily. So make some final | |
3131 | tweaks for the SYMBOL_PRESENT modes: | |
3132 | ||
3133 | If VAR_PRESENT is false, and the mode obtained by changing symbol to | |
3134 | var is cheaper, use this mode with small penalty. | |
3135 | If VAR_PRESENT is true, try whether the mode with | |
3136 | SYMBOL_PRESENT = false is cheaper even with cost of addition, and | |
3137 | if this is the case, use it. */ | |
f529eb25 | 3138 | add_c = add_cost (Pmode, speed); |
9b6564b5 | 3139 | for (i = 0; i < 8; i++) |
3140 | { | |
3141 | var_p = i & 1; | |
3142 | off_p = (i >> 1) & 1; | |
3143 | rat_p = (i >> 2) & 1; | |
3144 | ||
e7f482a0 | 3145 | acost = costs[mem_mode][0][1][off_p][rat_p] + 1; |
9b6564b5 | 3146 | if (var_p) |
3147 | acost += add_c; | |
3148 | ||
e7f482a0 | 3149 | if (acost < costs[mem_mode][1][var_p][off_p][rat_p]) |
3150 | costs[mem_mode][1][var_p][off_p][rat_p] = acost; | |
9b6564b5 | 3151 | } |
3152 | ||
3153 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3154 | { | |
3155 | fprintf (dump_file, "Address costs:\n"); | |
3156 | ||
3157 | for (i = 0; i < 16; i++) | |
3158 | { | |
3159 | sym_p = i & 1; | |
3160 | var_p = (i >> 1) & 1; | |
3161 | off_p = (i >> 2) & 1; | |
3162 | rat_p = (i >> 3) & 1; | |
3163 | ||
3164 | fprintf (dump_file, " "); | |
3165 | if (sym_p) | |
3166 | fprintf (dump_file, "sym + "); | |
3167 | if (var_p) | |
3168 | fprintf (dump_file, "var + "); | |
3169 | if (off_p) | |
3170 | fprintf (dump_file, "cst + "); | |
3171 | if (rat_p) | |
3172 | fprintf (dump_file, "rat * "); | |
3173 | ||
e7f482a0 | 3174 | acost = costs[mem_mode][sym_p][var_p][off_p][rat_p]; |
9b6564b5 | 3175 | fprintf (dump_file, "index costs %d\n", acost); |
3176 | } | |
3177 | fprintf (dump_file, "\n"); | |
3178 | } | |
dec41e98 | 3179 | } |
3180 | ||
3181 | bits = GET_MODE_BITSIZE (Pmode); | |
3182 | mask = ~(~(unsigned HOST_WIDE_INT) 0 << (bits - 1) << 1); | |
3183 | offset &= mask; | |
3184 | if ((offset >> (bits - 1) & 1)) | |
3185 | offset |= ~mask; | |
3186 | s_offset = offset; | |
3187 | ||
3188 | cost = 0; | |
636addb3 | 3189 | offset_p = (s_offset != 0 |
e7f482a0 | 3190 | && min_offset[mem_mode] <= s_offset |
3191 | && s_offset <= max_offset[mem_mode]); | |
dec41e98 | 3192 | ratio_p = (ratio != 1 |
e7f482a0 | 3193 | && multiplier_allowed_in_address_p (ratio, mem_mode)); |
dec41e98 | 3194 | |
3195 | if (ratio != 1 && !ratio_p) | |
f529eb25 | 3196 | cost += multiply_by_cost (ratio, Pmode, speed); |
dec41e98 | 3197 | |
3198 | if (s_offset && !offset_p && !symbol_present) | |
f529eb25 | 3199 | cost += add_cost (Pmode, speed); |
dec41e98 | 3200 | |
e7f482a0 | 3201 | acost = costs[mem_mode][symbol_present][var_present][offset_p][ratio_p]; |
3c2818b0 | 3202 | complexity = (symbol_present != 0) + (var_present != 0) + offset_p + ratio_p; |
3203 | return new_cost (cost + acost, complexity); | |
dec41e98 | 3204 | } |
dec41e98 | 3205 | |
f4d7629d | 3206 | /* Estimates cost of forcing expression EXPR into a variable. */ |
3207 | ||
3c2818b0 | 3208 | static comp_cost |
f529eb25 | 3209 | force_expr_to_var_cost (tree expr, bool speed) |
dec41e98 | 3210 | { |
3211 | static bool costs_initialized = false; | |
f529eb25 | 3212 | static unsigned integer_cost [2]; |
3213 | static unsigned symbol_cost [2]; | |
3214 | static unsigned address_cost [2]; | |
eb91f88e | 3215 | tree op0, op1; |
3c2818b0 | 3216 | comp_cost cost0, cost1, cost; |
eb91f88e | 3217 | enum machine_mode mode; |
dec41e98 | 3218 | |
3219 | if (!costs_initialized) | |
3220 | { | |
dec41e98 | 3221 | tree type = build_pointer_type (integer_type_node); |
7e995af7 | 3222 | tree var, addr; |
3223 | rtx x; | |
f529eb25 | 3224 | int i; |
7e995af7 | 3225 | |
3226 | var = create_tmp_var_raw (integer_type_node, "test_var"); | |
3227 | TREE_STATIC (var) = 1; | |
3228 | x = produce_memory_decl_rtl (var, NULL); | |
3229 | SET_DECL_RTL (var, x); | |
dec41e98 | 3230 | |
dec41e98 | 3231 | addr = build1 (ADDR_EXPR, type, var); |
dec41e98 | 3232 | |
f529eb25 | 3233 | |
3234 | for (i = 0; i < 2; i++) | |
dec41e98 | 3235 | { |
f529eb25 | 3236 | integer_cost[i] = computation_cost (build_int_cst (integer_type_node, |
3237 | 2000), i); | |
3238 | ||
3239 | symbol_cost[i] = computation_cost (addr, i) + 1; | |
3240 | ||
3241 | address_cost[i] | |
3242 | = computation_cost (build2 (POINTER_PLUS_EXPR, type, | |
3243 | addr, | |
3244 | build_int_cst (sizetype, 2000)), i) + 1; | |
3245 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3246 | { | |
3247 | fprintf (dump_file, "force_expr_to_var_cost %s costs:\n", i ? "speed" : "size"); | |
3248 | fprintf (dump_file, " integer %d\n", (int) integer_cost[i]); | |
3249 | fprintf (dump_file, " symbol %d\n", (int) symbol_cost[i]); | |
3250 | fprintf (dump_file, " address %d\n", (int) address_cost[i]); | |
3251 | fprintf (dump_file, " other %d\n", (int) target_spill_cost[i]); | |
3252 | fprintf (dump_file, "\n"); | |
3253 | } | |
dec41e98 | 3254 | } |
3255 | ||
3256 | costs_initialized = true; | |
3257 | } | |
3258 | ||
390955a6 | 3259 | STRIP_NOPS (expr); |
3260 | ||
dec41e98 | 3261 | if (SSA_VAR_P (expr)) |
3c2818b0 | 3262 | return zero_cost; |
dec41e98 | 3263 | |
71d9af81 | 3264 | if (is_gimple_min_invariant (expr)) |
dec41e98 | 3265 | { |
3266 | if (TREE_CODE (expr) == INTEGER_CST) | |
f529eb25 | 3267 | return new_cost (integer_cost [speed], 0); |
dec41e98 | 3268 | |
3269 | if (TREE_CODE (expr) == ADDR_EXPR) | |
3270 | { | |
3271 | tree obj = TREE_OPERAND (expr, 0); | |
3272 | ||
3273 | if (TREE_CODE (obj) == VAR_DECL | |
3274 | || TREE_CODE (obj) == PARM_DECL | |
3275 | || TREE_CODE (obj) == RESULT_DECL) | |
f529eb25 | 3276 | return new_cost (symbol_cost [speed], 0); |
dec41e98 | 3277 | } |
3278 | ||
f529eb25 | 3279 | return new_cost (address_cost [speed], 0); |
dec41e98 | 3280 | } |
3281 | ||
eb91f88e | 3282 | switch (TREE_CODE (expr)) |
3283 | { | |
0de36bdb | 3284 | case POINTER_PLUS_EXPR: |
eb91f88e | 3285 | case PLUS_EXPR: |
3286 | case MINUS_EXPR: | |
3287 | case MULT_EXPR: | |
3288 | op0 = TREE_OPERAND (expr, 0); | |
3289 | op1 = TREE_OPERAND (expr, 1); | |
390955a6 | 3290 | STRIP_NOPS (op0); |
3291 | STRIP_NOPS (op1); | |
eb91f88e | 3292 | |
3293 | if (is_gimple_val (op0)) | |
3c2818b0 | 3294 | cost0 = zero_cost; |
eb91f88e | 3295 | else |
f529eb25 | 3296 | cost0 = force_expr_to_var_cost (op0, speed); |
eb91f88e | 3297 | |
3298 | if (is_gimple_val (op1)) | |
3c2818b0 | 3299 | cost1 = zero_cost; |
eb91f88e | 3300 | else |
f529eb25 | 3301 | cost1 = force_expr_to_var_cost (op1, speed); |
eb91f88e | 3302 | |
3303 | break; | |
3304 | ||
3305 | default: | |
3306 | /* Just an arbitrary value, FIXME. */ | |
f529eb25 | 3307 | return new_cost (target_spill_cost[speed], 0); |
eb91f88e | 3308 | } |
3309 | ||
3310 | mode = TYPE_MODE (TREE_TYPE (expr)); | |
3311 | switch (TREE_CODE (expr)) | |
3312 | { | |
0de36bdb | 3313 | case POINTER_PLUS_EXPR: |
eb91f88e | 3314 | case PLUS_EXPR: |
3315 | case MINUS_EXPR: | |
f529eb25 | 3316 | cost = new_cost (add_cost (mode, speed), 0); |
eb91f88e | 3317 | break; |
3318 | ||
3319 | case MULT_EXPR: | |
3320 | if (cst_and_fits_in_hwi (op0)) | |
f529eb25 | 3321 | cost = new_cost (multiply_by_cost (int_cst_value (op0), mode, speed), 0); |
3322 | else if (cst_and_fits_in_hwi (op1)) | |
3323 | cost = new_cost (multiply_by_cost (int_cst_value (op1), mode, speed), 0); | |
eb91f88e | 3324 | else |
f529eb25 | 3325 | return new_cost (target_spill_cost [speed], 0); |
eb91f88e | 3326 | break; |
3327 | ||
3328 | default: | |
3329 | gcc_unreachable (); | |
3330 | } | |
3331 | ||
3c2818b0 | 3332 | cost = add_costs (cost, cost0); |
3333 | cost = add_costs (cost, cost1); | |
eb91f88e | 3334 | |
3335 | /* Bound the cost by target_spill_cost. The parts of complicated | |
3336 | computations often are either loop invariant or at least can | |
3337 | be shared between several iv uses, so letting this grow without | |
3338 | limits would not give reasonable results. */ | |
f529eb25 | 3339 | if (cost.cost > target_spill_cost [speed]) |
3340 | cost.cost = target_spill_cost [speed]; | |
3c2818b0 | 3341 | |
3342 | return cost; | |
dec41e98 | 3343 | } |
3344 | ||
f4d7629d | 3345 | /* Estimates cost of forcing EXPR into a variable. DEPENDS_ON is a set of the |
3346 | invariants the computation depends on. */ | |
3347 | ||
3c2818b0 | 3348 | static comp_cost |
f4d7629d | 3349 | force_var_cost (struct ivopts_data *data, |
3350 | tree expr, bitmap *depends_on) | |
3351 | { | |
3352 | if (depends_on) | |
3353 | { | |
3354 | fd_ivopts_data = data; | |
3355 | walk_tree (&expr, find_depends, depends_on, NULL); | |
3356 | } | |
3357 | ||
f529eb25 | 3358 | return force_expr_to_var_cost (expr, data->speed); |
f4d7629d | 3359 | } |
3360 | ||
dec41e98 | 3361 | /* Estimates cost of expressing address ADDR as var + symbol + offset. The |
3362 | value of offset is added to OFFSET, SYMBOL_PRESENT and VAR_PRESENT are set | |
3363 | to false if the corresponding part is missing. DEPENDS_ON is a set of the | |
3364 | invariants the computation depends on. */ | |
3365 | ||
3c2818b0 | 3366 | static comp_cost |
dec41e98 | 3367 | split_address_cost (struct ivopts_data *data, |
3368 | tree addr, bool *symbol_present, bool *var_present, | |
3369 | unsigned HOST_WIDE_INT *offset, bitmap *depends_on) | |
3370 | { | |
dbc64c75 | 3371 | tree core; |
3372 | HOST_WIDE_INT bitsize; | |
3373 | HOST_WIDE_INT bitpos; | |
3374 | tree toffset; | |
3375 | enum machine_mode mode; | |
3376 | int unsignedp, volatilep; | |
3377 | ||
3378 | core = get_inner_reference (addr, &bitsize, &bitpos, &toffset, &mode, | |
e7e9416e | 3379 | &unsignedp, &volatilep, false); |
dec41e98 | 3380 | |
dbc64c75 | 3381 | if (toffset != 0 |
3382 | || bitpos % BITS_PER_UNIT != 0 | |
3383 | || TREE_CODE (core) != VAR_DECL) | |
dec41e98 | 3384 | { |
3385 | *symbol_present = false; | |
3386 | *var_present = true; | |
3387 | fd_ivopts_data = data; | |
3388 | walk_tree (&addr, find_depends, depends_on, NULL); | |
f529eb25 | 3389 | return new_cost (target_spill_cost[data->speed], 0); |
dbc64c75 | 3390 | } |
3391 | ||
3392 | *offset += bitpos / BITS_PER_UNIT; | |
dec41e98 | 3393 | if (TREE_STATIC (core) |
3394 | || DECL_EXTERNAL (core)) | |
3395 | { | |
3396 | *symbol_present = true; | |
3397 | *var_present = false; | |
3c2818b0 | 3398 | return zero_cost; |
dec41e98 | 3399 | } |
3400 | ||
3401 | *symbol_present = false; | |
3402 | *var_present = true; | |
3c2818b0 | 3403 | return zero_cost; |
dec41e98 | 3404 | } |
3405 | ||
3406 | /* Estimates cost of expressing difference of addresses E1 - E2 as | |
3407 | var + symbol + offset. The value of offset is added to OFFSET, | |
3408 | SYMBOL_PRESENT and VAR_PRESENT are set to false if the corresponding | |
3409 | part is missing. DEPENDS_ON is a set of the invariants the computation | |
3410 | depends on. */ | |
3411 | ||
3c2818b0 | 3412 | static comp_cost |
dec41e98 | 3413 | ptr_difference_cost (struct ivopts_data *data, |
3414 | tree e1, tree e2, bool *symbol_present, bool *var_present, | |
3415 | unsigned HOST_WIDE_INT *offset, bitmap *depends_on) | |
3416 | { | |
dbc64c75 | 3417 | HOST_WIDE_INT diff = 0; |
3c2818b0 | 3418 | comp_cost cost; |
f529eb25 | 3419 | bool speed = optimize_loop_for_speed_p (data->current_loop); |
dec41e98 | 3420 | |
8c0963c4 | 3421 | gcc_assert (TREE_CODE (e1) == ADDR_EXPR); |
dec41e98 | 3422 | |
eb91f88e | 3423 | if (ptr_difference_const (e1, e2, &diff)) |
dec41e98 | 3424 | { |
3425 | *offset += diff; | |
3426 | *symbol_present = false; | |
3427 | *var_present = false; | |
3c2818b0 | 3428 | return zero_cost; |
dec41e98 | 3429 | } |
3430 | ||
3c2818b0 | 3431 | if (integer_zerop (e2)) |
dec41e98 | 3432 | return split_address_cost (data, TREE_OPERAND (e1, 0), |
3433 | symbol_present, var_present, offset, depends_on); | |
3434 | ||
3435 | *symbol_present = false; | |
3436 | *var_present = true; | |
3437 | ||
3438 | cost = force_var_cost (data, e1, depends_on); | |
3c2818b0 | 3439 | cost = add_costs (cost, force_var_cost (data, e2, depends_on)); |
f529eb25 | 3440 | cost.cost += add_cost (Pmode, speed); |
dec41e98 | 3441 | |
3442 | return cost; | |
3443 | } | |
3444 | ||
3445 | /* Estimates cost of expressing difference E1 - E2 as | |
3446 | var + symbol + offset. The value of offset is added to OFFSET, | |
3447 | SYMBOL_PRESENT and VAR_PRESENT are set to false if the corresponding | |
3448 | part is missing. DEPENDS_ON is a set of the invariants the computation | |
3449 | depends on. */ | |
3450 | ||
3c2818b0 | 3451 | static comp_cost |
dec41e98 | 3452 | difference_cost (struct ivopts_data *data, |
3453 | tree e1, tree e2, bool *symbol_present, bool *var_present, | |
3454 | unsigned HOST_WIDE_INT *offset, bitmap *depends_on) | |
3455 | { | |
3c2818b0 | 3456 | comp_cost cost; |
dec41e98 | 3457 | enum machine_mode mode = TYPE_MODE (TREE_TYPE (e1)); |
390955a6 | 3458 | unsigned HOST_WIDE_INT off1, off2; |
3459 | ||
651874e1 | 3460 | e1 = strip_offset (e1, &off1); |
3461 | e2 = strip_offset (e2, &off2); | |
390955a6 | 3462 | *offset += off1 - off2; |
dec41e98 | 3463 | |
390955a6 | 3464 | STRIP_NOPS (e1); |
3465 | STRIP_NOPS (e2); | |
dec41e98 | 3466 | |
3467 | if (TREE_CODE (e1) == ADDR_EXPR) | |
3468 | return ptr_difference_cost (data, e1, e2, symbol_present, var_present, offset, | |
3469 | depends_on); | |
3470 | *symbol_present = false; | |
3471 | ||
3472 | if (operand_equal_p (e1, e2, 0)) | |
3473 | { | |
3474 | *var_present = false; | |
3c2818b0 | 3475 | return zero_cost; |
dec41e98 | 3476 | } |
3477 | *var_present = true; | |
cd743a11 | 3478 | if (integer_zerop (e2)) |
dec41e98 | 3479 | return force_var_cost (data, e1, depends_on); |
3480 | ||
cd743a11 | 3481 | if (integer_zerop (e1)) |
dec41e98 | 3482 | { |
3483 | cost = force_var_cost (data, e2, depends_on); | |
f529eb25 | 3484 | cost.cost += multiply_by_cost (-1, mode, data->speed); |
dec41e98 | 3485 | |
3486 | return cost; | |
3487 | } | |
3488 | ||
3489 | cost = force_var_cost (data, e1, depends_on); | |
3c2818b0 | 3490 | cost = add_costs (cost, force_var_cost (data, e2, depends_on)); |
f529eb25 | 3491 | cost.cost += add_cost (mode, data->speed); |
dec41e98 | 3492 | |
3493 | return cost; | |
3494 | } | |
3495 | ||
3496 | /* Determines the cost of the computation by that USE is expressed | |
3497 | from induction variable CAND. If ADDRESS_P is true, we just need | |
3498 | to create an address from it, otherwise we want to get it into | |
3499 | register. A set of invariants we depend on is stored in | |
3500 | DEPENDS_ON. AT is the statement at that the value is computed. */ | |
3501 | ||
3c2818b0 | 3502 | static comp_cost |
dec41e98 | 3503 | get_computation_cost_at (struct ivopts_data *data, |
3504 | struct iv_use *use, struct iv_cand *cand, | |
75a70cf9 | 3505 | bool address_p, bitmap *depends_on, gimple at) |
dec41e98 | 3506 | { |
3507 | tree ubase = use->iv->base, ustep = use->iv->step; | |
3508 | tree cbase, cstep; | |
3509 | tree utype = TREE_TYPE (ubase), ctype; | |
d3610bea | 3510 | unsigned HOST_WIDE_INT cstepi, offset = 0; |
dec41e98 | 3511 | HOST_WIDE_INT ratio, aratio; |
3512 | bool var_present, symbol_present; | |
3c2818b0 | 3513 | comp_cost cost; |
3514 | unsigned n_sums; | |
d3610bea | 3515 | double_int rat; |
f529eb25 | 3516 | bool speed = optimize_bb_for_speed_p (gimple_bb (at)); |
dec41e98 | 3517 | |
3518 | *depends_on = NULL; | |
3519 | ||
3520 | /* Only consider real candidates. */ | |
3521 | if (!cand->iv) | |
3c2818b0 | 3522 | return infinite_cost; |
dec41e98 | 3523 | |
3524 | cbase = cand->iv->base; | |
3525 | cstep = cand->iv->step; | |
3526 | ctype = TREE_TYPE (cbase); | |
3527 | ||
3528 | if (TYPE_PRECISION (utype) > TYPE_PRECISION (ctype)) | |
3529 | { | |
3530 | /* We do not have a precision to express the values of use. */ | |
3c2818b0 | 3531 | return infinite_cost; |
dec41e98 | 3532 | } |
3533 | ||
065d134e | 3534 | if (address_p) |
3535 | { | |
3536 | /* Do not try to express address of an object with computation based | |
3537 | on address of a different object. This may cause problems in rtl | |
3538 | level alias analysis (that does not expect this to be happening, | |
3539 | as this is illegal in C), and would be unlikely to be useful | |
3540 | anyway. */ | |
3541 | if (use->iv->base_object | |
3542 | && cand->iv->base_object | |
3543 | && !operand_equal_p (use->iv->base_object, cand->iv->base_object, 0)) | |
3c2818b0 | 3544 | return infinite_cost; |
065d134e | 3545 | } |
3546 | ||
dec41e98 | 3547 | if (TYPE_PRECISION (utype) != TYPE_PRECISION (ctype)) |
3548 | { | |
3549 | /* TODO -- add direct handling of this case. */ | |
3550 | goto fallback; | |
3551 | } | |
3552 | ||
651874e1 | 3553 | /* CSTEPI is removed from the offset in case statement is after the |
3554 | increment. If the step is not constant, we use zero instead. | |
e446560c | 3555 | This is a bit imprecise (there is the extra addition), but |
651874e1 | 3556 | redundancy elimination is likely to transform the code so that |
3557 | it uses value of the variable before increment anyway, | |
3558 | so it is not that much unrealistic. */ | |
3559 | if (cst_and_fits_in_hwi (cstep)) | |
3560 | cstepi = int_cst_value (cstep); | |
3561 | else | |
3562 | cstepi = 0; | |
3563 | ||
d3610bea | 3564 | if (!constant_multiple_of (ustep, cstep, &rat)) |
3c2818b0 | 3565 | return infinite_cost; |
58f43b90 | 3566 | |
d3610bea | 3567 | if (double_int_fits_in_shwi_p (rat)) |
3568 | ratio = double_int_to_shwi (rat); | |
3569 | else | |
3c2818b0 | 3570 | return infinite_cost; |
dec41e98 | 3571 | |
3572 | /* use = ubase + ratio * (var - cbase). If either cbase is a constant | |
3573 | or ratio == 1, it is better to handle this like | |
3574 | ||
3575 | ubase - ratio * cbase + ratio * var | |
3576 | ||
3577 | (also holds in the case ratio == -1, TODO. */ | |
3578 | ||
651874e1 | 3579 | if (cst_and_fits_in_hwi (cbase)) |
dec41e98 | 3580 | { |
3581 | offset = - ratio * int_cst_value (cbase); | |
3c2818b0 | 3582 | cost = difference_cost (data, |
3583 | ubase, build_int_cst (utype, 0), | |
3584 | &symbol_present, &var_present, &offset, | |
3585 | depends_on); | |
dec41e98 | 3586 | } |
3587 | else if (ratio == 1) | |
3588 | { | |
3c2818b0 | 3589 | cost = difference_cost (data, |
3590 | ubase, cbase, | |
3591 | &symbol_present, &var_present, &offset, | |
3592 | depends_on); | |
dec41e98 | 3593 | } |
3594 | else | |
3595 | { | |
3c2818b0 | 3596 | cost = force_var_cost (data, cbase, depends_on); |
f529eb25 | 3597 | cost.cost += add_cost (TYPE_MODE (ctype), data->speed); |
3c2818b0 | 3598 | cost = add_costs (cost, |
3599 | difference_cost (data, | |
3600 | ubase, build_int_cst (utype, 0), | |
3601 | &symbol_present, &var_present, | |
3602 | &offset, depends_on)); | |
dec41e98 | 3603 | } |
3604 | ||
3605 | /* If we are after the increment, the value of the candidate is higher by | |
3606 | one iteration. */ | |
3607 | if (stmt_after_increment (data->current_loop, cand, at)) | |
3608 | offset -= ratio * cstepi; | |
3609 | ||
3610 | /* Now the computation is in shape symbol + var1 + const + ratio * var2. | |
3611 | (symbol/var/const parts may be omitted). If we are looking for an address, | |
3612 | find the cost of addressing this. */ | |
3613 | if (address_p) | |
3c2818b0 | 3614 | return add_costs (cost, get_address_cost (symbol_present, var_present, |
3615 | offset, ratio, | |
f529eb25 | 3616 | TYPE_MODE (TREE_TYPE (*use->op_p)), speed)); |
dec41e98 | 3617 | |
3618 | /* Otherwise estimate the costs for computing the expression. */ | |
3619 | aratio = ratio > 0 ? ratio : -ratio; | |
3620 | if (!symbol_present && !var_present && !offset) | |
3621 | { | |
3622 | if (ratio != 1) | |
f529eb25 | 3623 | cost.cost += multiply_by_cost (ratio, TYPE_MODE (ctype), speed); |
dec41e98 | 3624 | |
3625 | return cost; | |
3626 | } | |
3627 | ||
3628 | if (aratio != 1) | |
f529eb25 | 3629 | cost.cost += multiply_by_cost (aratio, TYPE_MODE (ctype), speed); |
dec41e98 | 3630 | |
3631 | n_sums = 1; | |
3632 | if (var_present | |
3633 | /* Symbol + offset should be compile-time computable. */ | |
3634 | && (symbol_present || offset)) | |
3635 | n_sums++; | |
3636 | ||
3c2818b0 | 3637 | /* Having offset does not affect runtime cost in case it is added to |
3638 | symbol, but it increases complexity. */ | |
3639 | if (offset) | |
3640 | cost.complexity++; | |
3641 | ||
f529eb25 | 3642 | cost.cost += n_sums * add_cost (TYPE_MODE (ctype), speed); |
3c2818b0 | 3643 | return cost; |
dec41e98 | 3644 | |
3645 | fallback: | |
3646 | { | |
3647 | /* Just get the expression, expand it and measure the cost. */ | |
3648 | tree comp = get_computation_at (data->current_loop, use, cand, at); | |
3649 | ||
3650 | if (!comp) | |
3c2818b0 | 3651 | return infinite_cost; |
dec41e98 | 3652 | |
3653 | if (address_p) | |
3654 | comp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (comp)), comp); | |
3655 | ||
f529eb25 | 3656 | return new_cost (computation_cost (comp, speed), 0); |
dec41e98 | 3657 | } |
3658 | } | |
3659 | ||
3660 | /* Determines the cost of the computation by that USE is expressed | |
3661 | from induction variable CAND. If ADDRESS_P is true, we just need | |
3662 | to create an address from it, otherwise we want to get it into | |
3663 | register. A set of invariants we depend on is stored in | |
3664 | DEPENDS_ON. */ | |
3665 | ||
3c2818b0 | 3666 | static comp_cost |
dec41e98 | 3667 | get_computation_cost (struct ivopts_data *data, |
3668 | struct iv_use *use, struct iv_cand *cand, | |
3669 | bool address_p, bitmap *depends_on) | |
3670 | { | |
3671 | return get_computation_cost_at (data, | |
3672 | use, cand, address_p, depends_on, use->stmt); | |
3673 | } | |
3674 | ||
3675 | /* Determines cost of basing replacement of USE on CAND in a generic | |
3676 | expression. */ | |
3677 | ||
00991688 | 3678 | static bool |
dec41e98 | 3679 | determine_use_iv_cost_generic (struct ivopts_data *data, |
3680 | struct iv_use *use, struct iv_cand *cand) | |
3681 | { | |
3682 | bitmap depends_on; | |
3c2818b0 | 3683 | comp_cost cost; |
d4caf099 | 3684 | |
3685 | /* The simple case first -- if we need to express value of the preserved | |
3686 | original biv, the cost is 0. This also prevents us from counting the | |
3687 | cost of increment twice -- once at this use and once in the cost of | |
3688 | the candidate. */ | |
3689 | if (cand->pos == IP_ORIGINAL | |
3690 | && cand->incremented_at == use->stmt) | |
3691 | { | |
3c2818b0 | 3692 | set_use_iv_cost (data, use, cand, zero_cost, NULL, NULL_TREE); |
d4caf099 | 3693 | return true; |
3694 | } | |
dec41e98 | 3695 | |
d4caf099 | 3696 | cost = get_computation_cost (data, use, cand, false, &depends_on); |
c4d3b428 | 3697 | set_use_iv_cost (data, use, cand, cost, depends_on, NULL_TREE); |
00991688 | 3698 | |
3c2818b0 | 3699 | return !infinite_cost_p (cost); |
dec41e98 | 3700 | } |
3701 | ||
3702 | /* Determines cost of basing replacement of USE on CAND in an address. */ | |
3703 | ||
00991688 | 3704 | static bool |
dec41e98 | 3705 | determine_use_iv_cost_address (struct ivopts_data *data, |
3706 | struct iv_use *use, struct iv_cand *cand) | |
3707 | { | |
3708 | bitmap depends_on; | |
3c2818b0 | 3709 | comp_cost cost = get_computation_cost (data, use, cand, true, &depends_on); |
dec41e98 | 3710 | |
c4d3b428 | 3711 | set_use_iv_cost (data, use, cand, cost, depends_on, NULL_TREE); |
00991688 | 3712 | |
3c2818b0 | 3713 | return !infinite_cost_p (cost); |
dec41e98 | 3714 | } |
3715 | ||
cf661063 | 3716 | /* Computes value of candidate CAND at position AT in iteration NITER, and |
3717 | stores it to VAL. */ | |
dec41e98 | 3718 | |
cf661063 | 3719 | static void |
75a70cf9 | 3720 | cand_value_at (struct loop *loop, struct iv_cand *cand, gimple at, tree niter, |
cf661063 | 3721 | aff_tree *val) |
dec41e98 | 3722 | { |
cf661063 | 3723 | aff_tree step, delta, nit; |
3724 | struct iv *iv = cand->iv; | |
dec41e98 | 3725 | tree type = TREE_TYPE (iv->base); |
06240723 | 3726 | tree steptype = type; |
3727 | if (POINTER_TYPE_P (type)) | |
3728 | steptype = sizetype; | |
dec41e98 | 3729 | |
06240723 | 3730 | tree_to_aff_combination (iv->step, steptype, &step); |
cf661063 | 3731 | tree_to_aff_combination (niter, TREE_TYPE (niter), &nit); |
06240723 | 3732 | aff_combination_convert (&nit, steptype); |
cf661063 | 3733 | aff_combination_mult (&nit, &step, &delta); |
dec41e98 | 3734 | if (stmt_after_increment (loop, cand, at)) |
cf661063 | 3735 | aff_combination_add (&delta, &step); |
dec41e98 | 3736 | |
cf661063 | 3737 | tree_to_aff_combination (iv->base, type, val); |
3738 | aff_combination_add (val, &delta); | |
dec41e98 | 3739 | } |
3740 | ||
b091dc59 | 3741 | /* Returns period of induction variable iv. */ |
3742 | ||
3743 | static tree | |
3744 | iv_period (struct iv *iv) | |
3745 | { | |
3746 | tree step = iv->step, period, type; | |
3747 | tree pow2div; | |
3748 | ||
3749 | gcc_assert (step && TREE_CODE (step) == INTEGER_CST); | |
3750 | ||
3751 | /* Period of the iv is gcd (step, type range). Since type range is power | |
3752 | of two, it suffices to determine the maximum power of two that divides | |
3753 | step. */ | |
3754 | pow2div = num_ending_zeros (step); | |
3755 | type = unsigned_type_for (TREE_TYPE (step)); | |
3756 | ||
3757 | period = build_low_bits_mask (type, | |
3758 | (TYPE_PRECISION (type) | |
3759 | - tree_low_cst (pow2div, 1))); | |
3760 | ||
3761 | return period; | |
3762 | } | |
3763 | ||
c4d3b428 | 3764 | /* Returns the comparison operator used when eliminating the iv USE. */ |
3765 | ||
3766 | static enum tree_code | |
3767 | iv_elimination_compare (struct ivopts_data *data, struct iv_use *use) | |
3768 | { | |
3769 | struct loop *loop = data->current_loop; | |
3770 | basic_block ex_bb; | |
3771 | edge exit; | |
3772 | ||
75a70cf9 | 3773 | ex_bb = gimple_bb (use->stmt); |
c4d3b428 | 3774 | exit = EDGE_SUCC (ex_bb, 0); |
3775 | if (flow_bb_inside_loop_p (loop, exit->dest)) | |
3776 | exit = EDGE_SUCC (ex_bb, 1); | |
3777 | ||
3778 | return (exit->flags & EDGE_TRUE_VALUE ? EQ_EXPR : NE_EXPR); | |
3779 | } | |
3780 | ||
dec41e98 | 3781 | /* Check whether it is possible to express the condition in USE by comparison |
c4d3b428 | 3782 | of candidate CAND. If so, store the value compared with to BOUND. */ |
dec41e98 | 3783 | |
3784 | static bool | |
b091dc59 | 3785 | may_eliminate_iv (struct ivopts_data *data, |
c4d3b428 | 3786 | struct iv_use *use, struct iv_cand *cand, tree *bound) |
dec41e98 | 3787 | { |
065d134e | 3788 | basic_block ex_bb; |
dec41e98 | 3789 | edge exit; |
1b0af592 | 3790 | tree nit, period; |
b091dc59 | 3791 | struct loop *loop = data->current_loop; |
cf661063 | 3792 | aff_tree bnd; |
1b0af592 | 3793 | |
651874e1 | 3794 | if (TREE_CODE (cand->iv->step) != INTEGER_CST) |
3795 | return false; | |
3796 | ||
14f25899 | 3797 | /* For now works only for exits that dominate the loop latch. |
3798 | TODO: extend to other conditions inside loop body. */ | |
75a70cf9 | 3799 | ex_bb = gimple_bb (use->stmt); |
065d134e | 3800 | if (use->stmt != last_stmt (ex_bb) |
75a70cf9 | 3801 | || gimple_code (use->stmt) != GIMPLE_COND |
3802 | || !dominated_by_p (CDI_DOMINATORS, loop->latch, ex_bb)) | |
dec41e98 | 3803 | return false; |
3804 | ||
065d134e | 3805 | exit = EDGE_SUCC (ex_bb, 0); |
3806 | if (flow_bb_inside_loop_p (loop, exit->dest)) | |
3807 | exit = EDGE_SUCC (ex_bb, 1); | |
3808 | if (flow_bb_inside_loop_p (loop, exit->dest)) | |
3809 | return false; | |
3810 | ||
dcd24d3c | 3811 | nit = niter_for_exit (data, exit); |
3812 | if (!nit) | |
dec41e98 | 3813 | return false; |
3814 | ||
14f25899 | 3815 | /* Determine whether we can use the variable to test the exit condition. |
3816 | This is the case iff the period of the induction variable is greater | |
3817 | than the number of iterations for which the exit condition is true. */ | |
b091dc59 | 3818 | period = iv_period (cand->iv); |
dec41e98 | 3819 | |
14f25899 | 3820 | /* If the number of iterations is constant, compare against it directly. */ |
3821 | if (TREE_CODE (nit) == INTEGER_CST) | |
3822 | { | |
3823 | if (!tree_int_cst_lt (nit, period)) | |
3824 | return false; | |
3825 | } | |
3826 | ||
3827 | /* If not, and if this is the only possible exit of the loop, see whether | |
3828 | we can get a conservative estimate on the number of iterations of the | |
3829 | entire loop and compare against that instead. */ | |
3830 | else if (loop_only_exit_p (loop, exit)) | |
3831 | { | |
3832 | double_int period_value, max_niter; | |
3833 | if (!estimated_loop_iterations (loop, true, &max_niter)) | |
3834 | return false; | |
3835 | period_value = tree_to_double_int (period); | |
3836 | if (double_int_ucmp (max_niter, period_value) >= 0) | |
3837 | return false; | |
3838 | } | |
3839 | ||
3840 | /* Otherwise, punt. */ | |
3841 | else | |
dec41e98 | 3842 | return false; |
3843 | ||
cf661063 | 3844 | cand_value_at (loop, cand, use->stmt, nit, &bnd); |
590f8b68 | 3845 | |
cf661063 | 3846 | *bound = aff_combination_to_tree (&bnd); |
590f8b68 | 3847 | /* It is unlikely that computing the number of iterations using division |
3848 | would be more profitable than keeping the original induction variable. */ | |
3849 | if (expression_expensive_p (*bound)) | |
3850 | return false; | |
dec41e98 | 3851 | return true; |
3852 | } | |
3853 | ||
3854 | /* Determines cost of basing replacement of USE on CAND in a condition. */ | |
3855 | ||
00991688 | 3856 | static bool |
dec41e98 | 3857 | determine_use_iv_cost_condition (struct ivopts_data *data, |
3858 | struct iv_use *use, struct iv_cand *cand) | |
3859 | { | |
02f8cd87 | 3860 | tree bound = NULL_TREE; |
3861 | struct iv *cmp_iv; | |
3862 | bitmap depends_on_elim = NULL, depends_on_express = NULL, depends_on; | |
3c2818b0 | 3863 | comp_cost elim_cost, express_cost, cost; |
02f8cd87 | 3864 | bool ok; |
dec41e98 | 3865 | |
3866 | /* Only consider real candidates. */ | |
3867 | if (!cand->iv) | |
3868 | { | |
3c2818b0 | 3869 | set_use_iv_cost (data, use, cand, infinite_cost, NULL, NULL_TREE); |
00991688 | 3870 | return false; |
dec41e98 | 3871 | } |
3872 | ||
02f8cd87 | 3873 | /* Try iv elimination. */ |
c4d3b428 | 3874 | if (may_eliminate_iv (data, use, cand, &bound)) |
1b0af592 | 3875 | { |
3876 | elim_cost = force_var_cost (data, bound, &depends_on_elim); | |
3877 | /* The bound is a loop invariant, so it will be only computed | |
3878 | once. */ | |
3c2818b0 | 3879 | elim_cost.cost /= AVG_LOOP_NITER (data->current_loop); |
1b0af592 | 3880 | } |
02f8cd87 | 3881 | else |
3c2818b0 | 3882 | elim_cost = infinite_cost; |
dec41e98 | 3883 | |
02f8cd87 | 3884 | /* Try expressing the original giv. If it is compared with an invariant, |
3885 | note that we cannot get rid of it. */ | |
75a70cf9 | 3886 | ok = extract_cond_operands (data, use->stmt, NULL, NULL, NULL, &cmp_iv); |
02f8cd87 | 3887 | gcc_assert (ok); |
dec41e98 | 3888 | |
02f8cd87 | 3889 | express_cost = get_computation_cost (data, use, cand, false, |
3890 | &depends_on_express); | |
3891 | fd_ivopts_data = data; | |
3892 | walk_tree (&cmp_iv->base, find_depends, &depends_on_express, NULL); | |
c4d3b428 | 3893 | |
b27dbec0 | 3894 | /* Choose the better approach, preferring the eliminated IV. */ |
3895 | if (compare_costs (elim_cost, express_cost) <= 0) | |
dec41e98 | 3896 | { |
02f8cd87 | 3897 | cost = elim_cost; |
3898 | depends_on = depends_on_elim; | |
3899 | depends_on_elim = NULL; | |
3900 | } | |
3901 | else | |
3902 | { | |
3903 | cost = express_cost; | |
3904 | depends_on = depends_on_express; | |
3905 | depends_on_express = NULL; | |
3906 | bound = NULL_TREE; | |
dec41e98 | 3907 | } |
3908 | ||
02f8cd87 | 3909 | set_use_iv_cost (data, use, cand, cost, depends_on, bound); |
3910 | ||
3911 | if (depends_on_elim) | |
3912 | BITMAP_FREE (depends_on_elim); | |
3913 | if (depends_on_express) | |
3914 | BITMAP_FREE (depends_on_express); | |
3915 | ||
3c2818b0 | 3916 | return !infinite_cost_p (cost); |
dec41e98 | 3917 | } |
3918 | ||
00991688 | 3919 | /* Determines cost of basing replacement of USE on CAND. Returns false |
3920 | if USE cannot be based on CAND. */ | |
dec41e98 | 3921 | |
00991688 | 3922 | static bool |
dec41e98 | 3923 | determine_use_iv_cost (struct ivopts_data *data, |
3924 | struct iv_use *use, struct iv_cand *cand) | |
3925 | { | |
3926 | switch (use->type) | |
3927 | { | |
3928 | case USE_NONLINEAR_EXPR: | |
00991688 | 3929 | return determine_use_iv_cost_generic (data, use, cand); |
dec41e98 | 3930 | |
dec41e98 | 3931 | case USE_ADDRESS: |
00991688 | 3932 | return determine_use_iv_cost_address (data, use, cand); |
dec41e98 | 3933 | |
3934 | case USE_COMPARE: | |
00991688 | 3935 | return determine_use_iv_cost_condition (data, use, cand); |
dec41e98 | 3936 | |
3937 | default: | |
8c0963c4 | 3938 | gcc_unreachable (); |
dec41e98 | 3939 | } |
3940 | } | |
3941 | ||
3942 | /* Determines costs of basing the use of the iv on an iv candidate. */ | |
3943 | ||
3944 | static void | |
3945 | determine_use_iv_costs (struct ivopts_data *data) | |
3946 | { | |
3947 | unsigned i, j; | |
3948 | struct iv_use *use; | |
3949 | struct iv_cand *cand; | |
27335ffd | 3950 | bitmap to_clear = BITMAP_ALLOC (NULL); |
dec41e98 | 3951 | |
3952 | alloc_use_cost_map (data); | |
3953 | ||
dec41e98 | 3954 | for (i = 0; i < n_iv_uses (data); i++) |
3955 | { | |
3956 | use = iv_use (data, i); | |
3957 | ||
3958 | if (data->consider_all_candidates) | |
3959 | { | |
3960 | for (j = 0; j < n_iv_cands (data); j++) | |
3961 | { | |
3962 | cand = iv_cand (data, j); | |
3963 | determine_use_iv_cost (data, use, cand); | |
3964 | } | |
3965 | } | |
3966 | else | |
3967 | { | |
0cc4271a | 3968 | bitmap_iterator bi; |
3969 | ||
3970 | EXECUTE_IF_SET_IN_BITMAP (use->related_cands, 0, j, bi) | |
dec41e98 | 3971 | { |
3972 | cand = iv_cand (data, j); | |
00991688 | 3973 | if (!determine_use_iv_cost (data, use, cand)) |
3974 | bitmap_set_bit (to_clear, j); | |
0cc4271a | 3975 | } |
00991688 | 3976 | |
3977 | /* Remove the candidates for that the cost is infinite from | |
3978 | the list of related candidates. */ | |
3979 | bitmap_and_compl_into (use->related_cands, to_clear); | |
3980 | bitmap_clear (to_clear); | |
dec41e98 | 3981 | } |
3982 | } | |
3983 | ||
27335ffd | 3984 | BITMAP_FREE (to_clear); |
00991688 | 3985 | |
dec41e98 | 3986 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3987 | { | |
3988 | fprintf (dump_file, "Use-candidate costs:\n"); | |
3989 | ||
3990 | for (i = 0; i < n_iv_uses (data); i++) | |
3991 | { | |
3992 | use = iv_use (data, i); | |
3993 | ||
3994 | fprintf (dump_file, "Use %d:\n", i); | |
3c2818b0 | 3995 | fprintf (dump_file, " cand\tcost\tcompl.\tdepends on\n"); |
dec41e98 | 3996 | for (j = 0; j < use->n_map_members; j++) |
3997 | { | |
3998 | if (!use->cost_map[j].cand | |
3c2818b0 | 3999 | || infinite_cost_p (use->cost_map[j].cost)) |
dec41e98 | 4000 | continue; |
4001 | ||
3c2818b0 | 4002 | fprintf (dump_file, " %d\t%d\t%d\t", |
dec41e98 | 4003 | use->cost_map[j].cand->id, |
3c2818b0 | 4004 | use->cost_map[j].cost.cost, |
4005 | use->cost_map[j].cost.complexity); | |
dec41e98 | 4006 | if (use->cost_map[j].depends_on) |
4007 | bitmap_print (dump_file, | |
4008 | use->cost_map[j].depends_on, "",""); | |
4009 | fprintf (dump_file, "\n"); | |
4010 | } | |
4011 | ||
4012 | fprintf (dump_file, "\n"); | |
4013 | } | |
4014 | fprintf (dump_file, "\n"); | |
4015 | } | |
4016 | } | |
4017 | ||
4018 | /* Determines cost of the candidate CAND. */ | |
4019 | ||
4020 | static void | |
4021 | determine_iv_cost (struct ivopts_data *data, struct iv_cand *cand) | |
4022 | { | |
3c2818b0 | 4023 | comp_cost cost_base; |
4024 | unsigned cost, cost_step; | |
5414270a | 4025 | tree base; |
dec41e98 | 4026 | |
4027 | if (!cand->iv) | |
4028 | { | |
4029 | cand->cost = 0; | |
4030 | return; | |
4031 | } | |
4032 | ||
4033 | /* There are two costs associated with the candidate -- its increment | |
4034 | and its initialization. The second is almost negligible for any loop | |
4035 | that rolls enough, so we take it just very little into account. */ | |
4036 | ||
4037 | base = cand->iv->base; | |
4038 | cost_base = force_var_cost (data, base, NULL); | |
f529eb25 | 4039 | cost_step = add_cost (TYPE_MODE (TREE_TYPE (base)), data->speed); |
dec41e98 | 4040 | |
3c2818b0 | 4041 | cost = cost_step + cost_base.cost / AVG_LOOP_NITER (current_loop); |
dec41e98 | 4042 | |
3c2818b0 | 4043 | /* Prefer the original ivs unless we may gain something by replacing it. |
f0b5f617 | 4044 | The reason is to make debugging simpler; so this is not relevant for |
3c2818b0 | 4045 | artificial ivs created by other optimization passes. */ |
4046 | if (cand->pos != IP_ORIGINAL | |
4047 | || DECL_ARTIFICIAL (SSA_NAME_VAR (cand->var_before))) | |
4048 | cost++; | |
dec41e98 | 4049 | |
4050 | /* Prefer not to insert statements into latch unless there are some | |
4051 | already (so that we do not create unnecessary jumps). */ | |
5414270a | 4052 | if (cand->pos == IP_END |
4053 | && empty_block_p (ip_end_pos (data->current_loop))) | |
3c2818b0 | 4054 | cost++; |
4055 | ||
4056 | cand->cost = cost; | |
dec41e98 | 4057 | } |
4058 | ||
4059 | /* Determines costs of computation of the candidates. */ | |
4060 | ||
4061 | static void | |
4062 | determine_iv_costs (struct ivopts_data *data) | |
4063 | { | |
4064 | unsigned i; | |
4065 | ||
4066 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4067 | { | |
4068 | fprintf (dump_file, "Candidate costs:\n"); | |
4069 | fprintf (dump_file, " cand\tcost\n"); | |
4070 | } | |
4071 | ||
4072 | for (i = 0; i < n_iv_cands (data); i++) | |
4073 | { | |
4074 | struct iv_cand *cand = iv_cand (data, i); | |
4075 | ||
4076 | determine_iv_cost (data, cand); | |
4077 | ||
4078 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4079 | fprintf (dump_file, " %d\t%d\n", i, cand->cost); | |
4080 | } | |
4081 | ||
ee9e7ecf | 4082 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4083 | fprintf (dump_file, "\n"); | |
dec41e98 | 4084 | } |
4085 | ||
4086 | /* Calculates cost for having SIZE induction variables. */ | |
4087 | ||
4088 | static unsigned | |
4089 | ivopts_global_cost_for_size (struct ivopts_data *data, unsigned size) | |
4090 | { | |
25153338 | 4091 | /* We add size to the cost, so that we prefer eliminating ivs |
4092 | if possible. */ | |
f529eb25 | 4093 | return size + estimate_reg_pressure_cost (size, data->regs_used, data->speed); |
dec41e98 | 4094 | } |
4095 | ||
4096 | /* For each size of the induction variable set determine the penalty. */ | |
4097 | ||
4098 | static void | |
4099 | determine_set_costs (struct ivopts_data *data) | |
4100 | { | |
4101 | unsigned j, n; | |
75a70cf9 | 4102 | gimple phi; |
4103 | gimple_stmt_iterator psi; | |
4104 | tree op; | |
dec41e98 | 4105 | struct loop *loop = data->current_loop; |
0cc4271a | 4106 | bitmap_iterator bi; |
dec41e98 | 4107 | |
4108 | /* We use the following model (definitely improvable, especially the | |
4109 | cost function -- TODO): | |
4110 | ||
4111 | We estimate the number of registers available (using MD data), name it A. | |
4112 | ||
4113 | We estimate the number of registers used by the loop, name it U. This | |
4114 | number is obtained as the number of loop phi nodes (not counting virtual | |
4115 | registers and bivs) + the number of variables from outside of the loop. | |
4116 | ||
4117 | We set a reserve R (free regs that are used for temporary computations, | |
4118 | etc.). For now the reserve is a constant 3. | |
4119 | ||
4120 | Let I be the number of induction variables. | |
4121 | ||
4122 | -- if U + I + R <= A, the cost is I * SMALL_COST (just not to encourage | |
4123 | make a lot of ivs without a reason). | |
4124 | -- if A - R < U + I <= A, the cost is I * PRES_COST | |
4125 | -- if U + I > A, the cost is I * PRES_COST and | |
4126 | number of uses * SPILL_COST * (U + I - A) / (U + I) is added. */ | |
4127 | ||
4128 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4129 | { | |
4130 | fprintf (dump_file, "Global costs:\n"); | |
4131 | fprintf (dump_file, " target_avail_regs %d\n", target_avail_regs); | |
f529eb25 | 4132 | fprintf (dump_file, " target_reg_cost %d\n", target_reg_cost[data->speed]); |
4133 | fprintf (dump_file, " target_spill_cost %d\n", target_spill_cost[data->speed]); | |
dec41e98 | 4134 | } |
4135 | ||
4136 | n = 0; | |
75a70cf9 | 4137 | for (psi = gsi_start_phis (loop->header); !gsi_end_p (psi); gsi_next (&psi)) |
dec41e98 | 4138 | { |
75a70cf9 | 4139 | phi = gsi_stmt (psi); |
dec41e98 | 4140 | op = PHI_RESULT (phi); |
4141 | ||
4142 | if (!is_gimple_reg (op)) | |
4143 | continue; | |
4144 | ||
4145 | if (get_iv (data, op)) | |
4146 | continue; | |
4147 | ||
4148 | n++; | |
4149 | } | |
4150 | ||
0cc4271a | 4151 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, j, bi) |
dec41e98 | 4152 | { |
4153 | struct version_info *info = ver_info (data, j); | |
4154 | ||
4155 | if (info->inv_id && info->has_nonlin_use) | |
4156 | n++; | |
0cc4271a | 4157 | } |
dec41e98 | 4158 | |
fe382241 | 4159 | data->regs_used = n; |
dec41e98 | 4160 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4161 | fprintf (dump_file, " regs_used %d\n", n); | |
4162 | ||
4163 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4164 | { | |
4165 | fprintf (dump_file, " cost for size:\n"); | |
4166 | fprintf (dump_file, " ivs\tcost\n"); | |
4167 | for (j = 0; j <= 2 * target_avail_regs; j++) | |
4168 | fprintf (dump_file, " %d\t%d\n", j, | |
4169 | ivopts_global_cost_for_size (data, j)); | |
4170 | fprintf (dump_file, "\n"); | |
4171 | } | |
4172 | } | |
4173 | ||
00991688 | 4174 | /* Returns true if A is a cheaper cost pair than B. */ |
dec41e98 | 4175 | |
00991688 | 4176 | static bool |
4177 | cheaper_cost_pair (struct cost_pair *a, struct cost_pair *b) | |
dec41e98 | 4178 | { |
3c2818b0 | 4179 | int cmp; |
4180 | ||
00991688 | 4181 | if (!a) |
4182 | return false; | |
dec41e98 | 4183 | |
00991688 | 4184 | if (!b) |
4185 | return true; | |
4186 | ||
3c2818b0 | 4187 | cmp = compare_costs (a->cost, b->cost); |
4188 | if (cmp < 0) | |
00991688 | 4189 | return true; |
4190 | ||
3c2818b0 | 4191 | if (cmp > 0) |
00991688 | 4192 | return false; |
4193 | ||
4194 | /* In case the costs are the same, prefer the cheaper candidate. */ | |
4195 | if (a->cand->cost < b->cand->cost) | |
4196 | return true; | |
4197 | ||
4198 | return false; | |
4199 | } | |
4200 | ||
4201 | /* Computes the cost field of IVS structure. */ | |
4202 | ||
4203 | static void | |
4204 | iv_ca_recount_cost (struct ivopts_data *data, struct iv_ca *ivs) | |
4205 | { | |
3c2818b0 | 4206 | comp_cost cost = ivs->cand_use_cost; |
4207 | cost.cost += ivs->cand_cost; | |
4208 | cost.cost += ivopts_global_cost_for_size (data, ivs->n_regs); | |
00991688 | 4209 | |
4210 | ivs->cost = cost; | |
4211 | } | |
4212 | ||
651874e1 | 4213 | /* Remove invariants in set INVS to set IVS. */ |
4214 | ||
4215 | static void | |
4216 | iv_ca_set_remove_invariants (struct iv_ca *ivs, bitmap invs) | |
4217 | { | |
4218 | bitmap_iterator bi; | |
4219 | unsigned iid; | |
4220 | ||
4221 | if (!invs) | |
4222 | return; | |
4223 | ||
4224 | EXECUTE_IF_SET_IN_BITMAP (invs, 0, iid, bi) | |
4225 | { | |
4226 | ivs->n_invariant_uses[iid]--; | |
4227 | if (ivs->n_invariant_uses[iid] == 0) | |
4228 | ivs->n_regs--; | |
4229 | } | |
4230 | } | |
4231 | ||
00991688 | 4232 | /* Set USE not to be expressed by any candidate in IVS. */ |
4233 | ||
4234 | static void | |
4235 | iv_ca_set_no_cp (struct ivopts_data *data, struct iv_ca *ivs, | |
4236 | struct iv_use *use) | |
4237 | { | |
651874e1 | 4238 | unsigned uid = use->id, cid; |
00991688 | 4239 | struct cost_pair *cp; |
00991688 | 4240 | |
4241 | cp = ivs->cand_for_use[uid]; | |
4242 | if (!cp) | |
4243 | return; | |
4244 | cid = cp->cand->id; | |
4245 | ||
4246 | ivs->bad_uses++; | |
4247 | ivs->cand_for_use[uid] = NULL; | |
4248 | ivs->n_cand_uses[cid]--; | |
4249 | ||
4250 | if (ivs->n_cand_uses[cid] == 0) | |
dec41e98 | 4251 | { |
00991688 | 4252 | bitmap_clear_bit (ivs->cands, cid); |
4253 | /* Do not count the pseudocandidates. */ | |
4254 | if (cp->cand->iv) | |
4255 | ivs->n_regs--; | |
13ea2c1f | 4256 | ivs->n_cands--; |
00991688 | 4257 | ivs->cand_cost -= cp->cand->cost; |
651874e1 | 4258 | |
4259 | iv_ca_set_remove_invariants (ivs, cp->cand->depends_on); | |
00991688 | 4260 | } |
4261 | ||
3c2818b0 | 4262 | ivs->cand_use_cost = sub_costs (ivs->cand_use_cost, cp->cost); |
00991688 | 4263 | |
651874e1 | 4264 | iv_ca_set_remove_invariants (ivs, cp->depends_on); |
4265 | iv_ca_recount_cost (data, ivs); | |
4266 | } | |
4267 | ||
4268 | /* Add invariants in set INVS to set IVS. */ | |
0a501ca6 | 4269 | |
651874e1 | 4270 | static void |
4271 | iv_ca_set_add_invariants (struct iv_ca *ivs, bitmap invs) | |
4272 | { | |
4273 | bitmap_iterator bi; | |
4274 | unsigned iid; | |
4275 | ||
4276 | if (!invs) | |
4277 | return; | |
4278 | ||
4279 | EXECUTE_IF_SET_IN_BITMAP (invs, 0, iid, bi) | |
00991688 | 4280 | { |
651874e1 | 4281 | ivs->n_invariant_uses[iid]++; |
4282 | if (ivs->n_invariant_uses[iid] == 1) | |
4283 | ivs->n_regs++; | |
dec41e98 | 4284 | } |
00991688 | 4285 | } |
4286 | ||
4287 | /* Set cost pair for USE in set IVS to CP. */ | |
4288 | ||
4289 | static void | |
4290 | iv_ca_set_cp (struct ivopts_data *data, struct iv_ca *ivs, | |
4291 | struct iv_use *use, struct cost_pair *cp) | |
4292 | { | |
651874e1 | 4293 | unsigned uid = use->id, cid; |
00991688 | 4294 | |
4295 | if (ivs->cand_for_use[uid] == cp) | |
4296 | return; | |
4297 | ||
4298 | if (ivs->cand_for_use[uid]) | |
4299 | iv_ca_set_no_cp (data, ivs, use); | |
4300 | ||
4301 | if (cp) | |
dec41e98 | 4302 | { |
00991688 | 4303 | cid = cp->cand->id; |
dec41e98 | 4304 | |
00991688 | 4305 | ivs->bad_uses--; |
4306 | ivs->cand_for_use[uid] = cp; | |
4307 | ivs->n_cand_uses[cid]++; | |
4308 | if (ivs->n_cand_uses[cid] == 1) | |
dec41e98 | 4309 | { |
00991688 | 4310 | bitmap_set_bit (ivs->cands, cid); |
4311 | /* Do not count the pseudocandidates. */ | |
4312 | if (cp->cand->iv) | |
4313 | ivs->n_regs++; | |
13ea2c1f | 4314 | ivs->n_cands++; |
00991688 | 4315 | ivs->cand_cost += cp->cand->cost; |
00991688 | 4316 | |
651874e1 | 4317 | iv_ca_set_add_invariants (ivs, cp->cand->depends_on); |
dec41e98 | 4318 | } |
4319 | ||
3c2818b0 | 4320 | ivs->cand_use_cost = add_costs (ivs->cand_use_cost, cp->cost); |
651874e1 | 4321 | iv_ca_set_add_invariants (ivs, cp->depends_on); |
00991688 | 4322 | iv_ca_recount_cost (data, ivs); |
0cc4271a | 4323 | } |
00991688 | 4324 | } |
4325 | ||
4326 | /* Extend set IVS by expressing USE by some of the candidates in it | |
4327 | if possible. */ | |
4328 | ||
4329 | static void | |
4330 | iv_ca_add_use (struct ivopts_data *data, struct iv_ca *ivs, | |
4331 | struct iv_use *use) | |
4332 | { | |
4333 | struct cost_pair *best_cp = NULL, *cp; | |
4334 | bitmap_iterator bi; | |
4335 | unsigned i; | |
dec41e98 | 4336 | |
00991688 | 4337 | gcc_assert (ivs->upto >= use->id); |
4338 | ||
4339 | if (ivs->upto == use->id) | |
4340 | { | |
4341 | ivs->upto++; | |
4342 | ivs->bad_uses++; | |
4343 | } | |
dec41e98 | 4344 | |
00991688 | 4345 | EXECUTE_IF_SET_IN_BITMAP (ivs->cands, 0, i, bi) |
4346 | { | |
4347 | cp = get_use_iv_cost (data, use, iv_cand (data, i)); | |
dec41e98 | 4348 | |
00991688 | 4349 | if (cheaper_cost_pair (cp, best_cp)) |
4350 | best_cp = cp; | |
4351 | } | |
dec41e98 | 4352 | |
00991688 | 4353 | iv_ca_set_cp (data, ivs, use, best_cp); |
dec41e98 | 4354 | } |
4355 | ||
00991688 | 4356 | /* Get cost for assignment IVS. */ |
dec41e98 | 4357 | |
3c2818b0 | 4358 | static comp_cost |
00991688 | 4359 | iv_ca_cost (struct iv_ca *ivs) |
4360 | { | |
18381619 | 4361 | /* This was a conditional expression but it triggered a bug in |
4362 | Sun C 5.5. */ | |
ce6cd837 | 4363 | if (ivs->bad_uses) |
4364 | return infinite_cost; | |
4365 | else | |
4366 | return ivs->cost; | |
00991688 | 4367 | } |
4368 | ||
4369 | /* Returns true if all dependences of CP are among invariants in IVS. */ | |
4370 | ||
4371 | static bool | |
4372 | iv_ca_has_deps (struct iv_ca *ivs, struct cost_pair *cp) | |
dec41e98 | 4373 | { |
4374 | unsigned i; | |
0cc4271a | 4375 | bitmap_iterator bi; |
dec41e98 | 4376 | |
00991688 | 4377 | if (!cp->depends_on) |
4378 | return true; | |
4379 | ||
4380 | EXECUTE_IF_SET_IN_BITMAP (cp->depends_on, 0, i, bi) | |
dec41e98 | 4381 | { |
00991688 | 4382 | if (ivs->n_invariant_uses[i] == 0) |
4383 | return false; | |
4384 | } | |
4385 | ||
4386 | return true; | |
4387 | } | |
4388 | ||
4389 | /* Creates change of expressing USE by NEW_CP instead of OLD_CP and chains | |
4390 | it before NEXT_CHANGE. */ | |
4391 | ||
4392 | static struct iv_ca_delta * | |
4393 | iv_ca_delta_add (struct iv_use *use, struct cost_pair *old_cp, | |
4394 | struct cost_pair *new_cp, struct iv_ca_delta *next_change) | |
4395 | { | |
4c36ffe6 | 4396 | struct iv_ca_delta *change = XNEW (struct iv_ca_delta); |
00991688 | 4397 | |
4398 | change->use = use; | |
4399 | change->old_cp = old_cp; | |
4400 | change->new_cp = new_cp; | |
4401 | change->next_change = next_change; | |
4402 | ||
4403 | return change; | |
4404 | } | |
4405 | ||
13ea2c1f | 4406 | /* Joins two lists of changes L1 and L2. Destructive -- old lists |
f7f07c95 | 4407 | are rewritten. */ |
13ea2c1f | 4408 | |
4409 | static struct iv_ca_delta * | |
4410 | iv_ca_delta_join (struct iv_ca_delta *l1, struct iv_ca_delta *l2) | |
4411 | { | |
4412 | struct iv_ca_delta *last; | |
4413 | ||
4414 | if (!l2) | |
4415 | return l1; | |
4416 | ||
4417 | if (!l1) | |
4418 | return l2; | |
4419 | ||
4420 | for (last = l1; last->next_change; last = last->next_change) | |
4421 | continue; | |
4422 | last->next_change = l2; | |
4423 | ||
4424 | return l1; | |
4425 | } | |
4426 | ||
00991688 | 4427 | /* Returns candidate by that USE is expressed in IVS. */ |
4428 | ||
4429 | static struct cost_pair * | |
4430 | iv_ca_cand_for_use (struct iv_ca *ivs, struct iv_use *use) | |
4431 | { | |
4432 | return ivs->cand_for_use[use->id]; | |
4433 | } | |
4434 | ||
13ea2c1f | 4435 | /* Reverse the list of changes DELTA, forming the inverse to it. */ |
4436 | ||
4437 | static struct iv_ca_delta * | |
4438 | iv_ca_delta_reverse (struct iv_ca_delta *delta) | |
4439 | { | |
4440 | struct iv_ca_delta *act, *next, *prev = NULL; | |
4441 | struct cost_pair *tmp; | |
4442 | ||
4443 | for (act = delta; act; act = next) | |
4444 | { | |
4445 | next = act->next_change; | |
4446 | act->next_change = prev; | |
4447 | prev = act; | |
4448 | ||
4449 | tmp = act->old_cp; | |
4450 | act->old_cp = act->new_cp; | |
4451 | act->new_cp = tmp; | |
4452 | } | |
4453 | ||
4454 | return prev; | |
4455 | } | |
4456 | ||
00991688 | 4457 | /* Commit changes in DELTA to IVS. If FORWARD is false, the changes are |
4458 | reverted instead. */ | |
4459 | ||
4460 | static void | |
4461 | iv_ca_delta_commit (struct ivopts_data *data, struct iv_ca *ivs, | |
4462 | struct iv_ca_delta *delta, bool forward) | |
4463 | { | |
4464 | struct cost_pair *from, *to; | |
13ea2c1f | 4465 | struct iv_ca_delta *act; |
00991688 | 4466 | |
13ea2c1f | 4467 | if (!forward) |
4468 | delta = iv_ca_delta_reverse (delta); | |
00991688 | 4469 | |
13ea2c1f | 4470 | for (act = delta; act; act = act->next_change) |
4471 | { | |
4472 | from = act->old_cp; | |
4473 | to = act->new_cp; | |
4474 | gcc_assert (iv_ca_cand_for_use (ivs, act->use) == from); | |
4475 | iv_ca_set_cp (data, ivs, act->use, to); | |
dec41e98 | 4476 | } |
13ea2c1f | 4477 | |
4478 | if (!forward) | |
4479 | iv_ca_delta_reverse (delta); | |
00991688 | 4480 | } |
dec41e98 | 4481 | |
00991688 | 4482 | /* Returns true if CAND is used in IVS. */ |
dec41e98 | 4483 | |
00991688 | 4484 | static bool |
4485 | iv_ca_cand_used_p (struct iv_ca *ivs, struct iv_cand *cand) | |
4486 | { | |
4487 | return ivs->n_cand_uses[cand->id] > 0; | |
4488 | } | |
dec41e98 | 4489 | |
13ea2c1f | 4490 | /* Returns number of induction variable candidates in the set IVS. */ |
4491 | ||
4492 | static unsigned | |
4493 | iv_ca_n_cands (struct iv_ca *ivs) | |
4494 | { | |
4495 | return ivs->n_cands; | |
4496 | } | |
4497 | ||
00991688 | 4498 | /* Free the list of changes DELTA. */ |
4499 | ||
4500 | static void | |
4501 | iv_ca_delta_free (struct iv_ca_delta **delta) | |
4502 | { | |
4503 | struct iv_ca_delta *act, *next; | |
4504 | ||
4505 | for (act = *delta; act; act = next) | |
0cc4271a | 4506 | { |
00991688 | 4507 | next = act->next_change; |
4508 | free (act); | |
0cc4271a | 4509 | } |
dec41e98 | 4510 | |
00991688 | 4511 | *delta = NULL; |
4512 | } | |
4513 | ||
4514 | /* Allocates new iv candidates assignment. */ | |
4515 | ||
4516 | static struct iv_ca * | |
4517 | iv_ca_new (struct ivopts_data *data) | |
4518 | { | |
4c36ffe6 | 4519 | struct iv_ca *nw = XNEW (struct iv_ca); |
dec41e98 | 4520 | |
00991688 | 4521 | nw->upto = 0; |
4522 | nw->bad_uses = 0; | |
4c36ffe6 | 4523 | nw->cand_for_use = XCNEWVEC (struct cost_pair *, n_iv_uses (data)); |
4524 | nw->n_cand_uses = XCNEWVEC (unsigned, n_iv_cands (data)); | |
27335ffd | 4525 | nw->cands = BITMAP_ALLOC (NULL); |
13ea2c1f | 4526 | nw->n_cands = 0; |
00991688 | 4527 | nw->n_regs = 0; |
3c2818b0 | 4528 | nw->cand_use_cost = zero_cost; |
00991688 | 4529 | nw->cand_cost = 0; |
4c36ffe6 | 4530 | nw->n_invariant_uses = XCNEWVEC (unsigned, data->max_inv_id + 1); |
3c2818b0 | 4531 | nw->cost = zero_cost; |
00991688 | 4532 | |
4533 | return nw; | |
4534 | } | |
4535 | ||
4536 | /* Free memory occupied by the set IVS. */ | |
4537 | ||
4538 | static void | |
4539 | iv_ca_free (struct iv_ca **ivs) | |
4540 | { | |
4541 | free ((*ivs)->cand_for_use); | |
4542 | free ((*ivs)->n_cand_uses); | |
27335ffd | 4543 | BITMAP_FREE ((*ivs)->cands); |
00991688 | 4544 | free ((*ivs)->n_invariant_uses); |
4545 | free (*ivs); | |
4546 | *ivs = NULL; | |
4547 | } | |
4548 | ||
4549 | /* Dumps IVS to FILE. */ | |
4550 | ||
4551 | static void | |
4552 | iv_ca_dump (struct ivopts_data *data, FILE *file, struct iv_ca *ivs) | |
4553 | { | |
4554 | const char *pref = " invariants "; | |
4555 | unsigned i; | |
3c2818b0 | 4556 | comp_cost cost = iv_ca_cost (ivs); |
00991688 | 4557 | |
3c2818b0 | 4558 | fprintf (file, " cost %d (complexity %d)\n", cost.cost, cost.complexity); |
00991688 | 4559 | bitmap_print (file, ivs->cands, " candidates ","\n"); |
4560 | ||
4561 | for (i = 1; i <= data->max_inv_id; i++) | |
4562 | if (ivs->n_invariant_uses[i]) | |
4563 | { | |
4564 | fprintf (file, "%s%d", pref, i); | |
4565 | pref = ", "; | |
4566 | } | |
4567 | fprintf (file, "\n"); | |
4568 | } | |
4569 | ||
4570 | /* Try changing candidate in IVS to CAND for each use. Return cost of the | |
13ea2c1f | 4571 | new set, and store differences in DELTA. Number of induction variables |
4572 | in the new set is stored to N_IVS. */ | |
00991688 | 4573 | |
3c2818b0 | 4574 | static comp_cost |
00991688 | 4575 | iv_ca_extend (struct ivopts_data *data, struct iv_ca *ivs, |
13ea2c1f | 4576 | struct iv_cand *cand, struct iv_ca_delta **delta, |
4577 | unsigned *n_ivs) | |
00991688 | 4578 | { |
3c2818b0 | 4579 | unsigned i; |
4580 | comp_cost cost; | |
00991688 | 4581 | struct iv_use *use; |
4582 | struct cost_pair *old_cp, *new_cp; | |
4583 | ||
4584 | *delta = NULL; | |
4585 | for (i = 0; i < ivs->upto; i++) | |
4586 | { | |
4587 | use = iv_use (data, i); | |
4588 | old_cp = iv_ca_cand_for_use (ivs, use); | |
4589 | ||
4590 | if (old_cp | |
4591 | && old_cp->cand == cand) | |
4592 | continue; | |
4593 | ||
4594 | new_cp = get_use_iv_cost (data, use, cand); | |
4595 | if (!new_cp) | |
4596 | continue; | |
4597 | ||
4598 | if (!iv_ca_has_deps (ivs, new_cp)) | |
4599 | continue; | |
4600 | ||
4601 | if (!cheaper_cost_pair (new_cp, old_cp)) | |
4602 | continue; | |
4603 | ||
4604 | *delta = iv_ca_delta_add (use, old_cp, new_cp, *delta); | |
4605 | } | |
4606 | ||
4607 | iv_ca_delta_commit (data, ivs, *delta, true); | |
4608 | cost = iv_ca_cost (ivs); | |
13ea2c1f | 4609 | if (n_ivs) |
4610 | *n_ivs = iv_ca_n_cands (ivs); | |
00991688 | 4611 | iv_ca_delta_commit (data, ivs, *delta, false); |
dec41e98 | 4612 | |
4613 | return cost; | |
4614 | } | |
4615 | ||
d2aa5f30 | 4616 | /* Try narrowing set IVS by removing CAND. Return the cost of |
00991688 | 4617 | the new set and store the differences in DELTA. */ |
dec41e98 | 4618 | |
3c2818b0 | 4619 | static comp_cost |
00991688 | 4620 | iv_ca_narrow (struct ivopts_data *data, struct iv_ca *ivs, |
4621 | struct iv_cand *cand, struct iv_ca_delta **delta) | |
dec41e98 | 4622 | { |
00991688 | 4623 | unsigned i, ci; |
4624 | struct iv_use *use; | |
4625 | struct cost_pair *old_cp, *new_cp, *cp; | |
4626 | bitmap_iterator bi; | |
4627 | struct iv_cand *cnd; | |
3c2818b0 | 4628 | comp_cost cost; |
00991688 | 4629 | |
4630 | *delta = NULL; | |
4631 | for (i = 0; i < n_iv_uses (data); i++) | |
4632 | { | |
4633 | use = iv_use (data, i); | |
4634 | ||
4635 | old_cp = iv_ca_cand_for_use (ivs, use); | |
4636 | if (old_cp->cand != cand) | |
4637 | continue; | |
4638 | ||
4639 | new_cp = NULL; | |
4640 | ||
4641 | if (data->consider_all_candidates) | |
4642 | { | |
4643 | EXECUTE_IF_SET_IN_BITMAP (ivs->cands, 0, ci, bi) | |
4644 | { | |
4645 | if (ci == cand->id) | |
4646 | continue; | |
4647 | ||
4648 | cnd = iv_cand (data, ci); | |
4649 | ||
4650 | cp = get_use_iv_cost (data, use, cnd); | |
4651 | if (!cp) | |
4652 | continue; | |
4653 | if (!iv_ca_has_deps (ivs, cp)) | |
4654 | continue; | |
4655 | ||
4656 | if (!cheaper_cost_pair (cp, new_cp)) | |
4657 | continue; | |
4658 | ||
4659 | new_cp = cp; | |
4660 | } | |
4661 | } | |
4662 | else | |
4663 | { | |
4664 | EXECUTE_IF_AND_IN_BITMAP (use->related_cands, ivs->cands, 0, ci, bi) | |
4665 | { | |
4666 | if (ci == cand->id) | |
4667 | continue; | |
4668 | ||
4669 | cnd = iv_cand (data, ci); | |
4670 | ||
4671 | cp = get_use_iv_cost (data, use, cnd); | |
4672 | if (!cp) | |
4673 | continue; | |
4674 | if (!iv_ca_has_deps (ivs, cp)) | |
4675 | continue; | |
4676 | ||
4677 | if (!cheaper_cost_pair (cp, new_cp)) | |
4678 | continue; | |
4679 | ||
4680 | new_cp = cp; | |
4681 | } | |
4682 | } | |
4683 | ||
4684 | if (!new_cp) | |
4685 | { | |
4686 | iv_ca_delta_free (delta); | |
3c2818b0 | 4687 | return infinite_cost; |
00991688 | 4688 | } |
4689 | ||
4690 | *delta = iv_ca_delta_add (use, old_cp, new_cp, *delta); | |
4691 | } | |
4692 | ||
4693 | iv_ca_delta_commit (data, ivs, *delta, true); | |
4694 | cost = iv_ca_cost (ivs); | |
4695 | iv_ca_delta_commit (data, ivs, *delta, false); | |
4696 | ||
4697 | return cost; | |
dec41e98 | 4698 | } |
4699 | ||
13ea2c1f | 4700 | /* Try optimizing the set of candidates IVS by removing candidates different |
4701 | from to EXCEPT_CAND from it. Return cost of the new set, and store | |
4702 | differences in DELTA. */ | |
4703 | ||
3c2818b0 | 4704 | static comp_cost |
13ea2c1f | 4705 | iv_ca_prune (struct ivopts_data *data, struct iv_ca *ivs, |
4706 | struct iv_cand *except_cand, struct iv_ca_delta **delta) | |
4707 | { | |
4708 | bitmap_iterator bi; | |
4709 | struct iv_ca_delta *act_delta, *best_delta; | |
3c2818b0 | 4710 | unsigned i; |
4711 | comp_cost best_cost, acost; | |
13ea2c1f | 4712 | struct iv_cand *cand; |
4713 | ||
4714 | best_delta = NULL; | |
4715 | best_cost = iv_ca_cost (ivs); | |
4716 | ||
4717 | EXECUTE_IF_SET_IN_BITMAP (ivs->cands, 0, i, bi) | |
4718 | { | |
4719 | cand = iv_cand (data, i); | |
4720 | ||
4721 | if (cand == except_cand) | |
4722 | continue; | |
4723 | ||
4724 | acost = iv_ca_narrow (data, ivs, cand, &act_delta); | |
4725 | ||
3c2818b0 | 4726 | if (compare_costs (acost, best_cost) < 0) |
13ea2c1f | 4727 | { |
4728 | best_cost = acost; | |
4729 | iv_ca_delta_free (&best_delta); | |
4730 | best_delta = act_delta; | |
4731 | } | |
4732 | else | |
4733 | iv_ca_delta_free (&act_delta); | |
4734 | } | |
4735 | ||
4736 | if (!best_delta) | |
4737 | { | |
4738 | *delta = NULL; | |
4739 | return best_cost; | |
4740 | } | |
4741 | ||
4742 | /* Recurse to possibly remove other unnecessary ivs. */ | |
4743 | iv_ca_delta_commit (data, ivs, best_delta, true); | |
4744 | best_cost = iv_ca_prune (data, ivs, except_cand, delta); | |
4745 | iv_ca_delta_commit (data, ivs, best_delta, false); | |
4746 | *delta = iv_ca_delta_join (best_delta, *delta); | |
4747 | return best_cost; | |
4748 | } | |
4749 | ||
00991688 | 4750 | /* Tries to extend the sets IVS in the best possible way in order |
dec41e98 | 4751 | to express the USE. */ |
4752 | ||
4753 | static bool | |
00991688 | 4754 | try_add_cand_for (struct ivopts_data *data, struct iv_ca *ivs, |
dec41e98 | 4755 | struct iv_use *use) |
4756 | { | |
3c2818b0 | 4757 | comp_cost best_cost, act_cost; |
dec41e98 | 4758 | unsigned i; |
dede8dcc | 4759 | bitmap_iterator bi; |
4760 | struct iv_cand *cand; | |
00991688 | 4761 | struct iv_ca_delta *best_delta = NULL, *act_delta; |
4762 | struct cost_pair *cp; | |
4763 | ||
4764 | iv_ca_add_use (data, ivs, use); | |
4765 | best_cost = iv_ca_cost (ivs); | |
dec41e98 | 4766 | |
00991688 | 4767 | cp = iv_ca_cand_for_use (ivs, use); |
4768 | if (cp) | |
4769 | { | |
4770 | best_delta = iv_ca_delta_add (use, NULL, cp, NULL); | |
4771 | iv_ca_set_no_cp (data, ivs, use); | |
4772 | } | |
dec41e98 | 4773 | |
3c2818b0 | 4774 | /* First try important candidates not based on any memory object. Only if |
4775 | this fails, try the specific ones. Rationale -- in loops with many | |
4776 | variables the best choice often is to use just one generic biv. If we | |
4777 | added here many ivs specific to the uses, the optimization algorithm later | |
4778 | would be likely to get stuck in a local minimum, thus causing us to create | |
4779 | too many ivs. The approach from few ivs to more seems more likely to be | |
4780 | successful -- starting from few ivs, replacing an expensive use by a | |
4781 | specific iv should always be a win. */ | |
dede8dcc | 4782 | EXECUTE_IF_SET_IN_BITMAP (data->important_candidates, 0, i, bi) |
dec41e98 | 4783 | { |
dede8dcc | 4784 | cand = iv_cand (data, i); |
4785 | ||
3c2818b0 | 4786 | if (cand->iv->base_object != NULL_TREE) |
4787 | continue; | |
4788 | ||
00991688 | 4789 | if (iv_ca_cand_used_p (ivs, cand)) |
dec41e98 | 4790 | continue; |
4791 | ||
00991688 | 4792 | cp = get_use_iv_cost (data, use, cand); |
4793 | if (!cp) | |
4794 | continue; | |
4795 | ||
4796 | iv_ca_set_cp (data, ivs, use, cp); | |
13ea2c1f | 4797 | act_cost = iv_ca_extend (data, ivs, cand, &act_delta, NULL); |
00991688 | 4798 | iv_ca_set_no_cp (data, ivs, use); |
4799 | act_delta = iv_ca_delta_add (use, NULL, cp, act_delta); | |
dec41e98 | 4800 | |
3c2818b0 | 4801 | if (compare_costs (act_cost, best_cost) < 0) |
dec41e98 | 4802 | { |
4803 | best_cost = act_cost; | |
00991688 | 4804 | |
4805 | iv_ca_delta_free (&best_delta); | |
4806 | best_delta = act_delta; | |
dec41e98 | 4807 | } |
00991688 | 4808 | else |
4809 | iv_ca_delta_free (&act_delta); | |
dec41e98 | 4810 | } |
4811 | ||
3c2818b0 | 4812 | if (infinite_cost_p (best_cost)) |
dede8dcc | 4813 | { |
4814 | for (i = 0; i < use->n_map_members; i++) | |
4815 | { | |
4816 | cp = use->cost_map + i; | |
00991688 | 4817 | cand = cp->cand; |
4818 | if (!cand) | |
dede8dcc | 4819 | continue; |
4820 | ||
4821 | /* Already tried this. */ | |
3c2818b0 | 4822 | if (cand->important && cand->iv->base_object == NULL_TREE) |
00991688 | 4823 | continue; |
4824 | ||
4825 | if (iv_ca_cand_used_p (ivs, cand)) | |
dede8dcc | 4826 | continue; |
4827 | ||
00991688 | 4828 | act_delta = NULL; |
4829 | iv_ca_set_cp (data, ivs, use, cp); | |
13ea2c1f | 4830 | act_cost = iv_ca_extend (data, ivs, cand, &act_delta, NULL); |
00991688 | 4831 | iv_ca_set_no_cp (data, ivs, use); |
4832 | act_delta = iv_ca_delta_add (use, iv_ca_cand_for_use (ivs, use), | |
4833 | cp, act_delta); | |
dede8dcc | 4834 | |
3c2818b0 | 4835 | if (compare_costs (act_cost, best_cost) < 0) |
dede8dcc | 4836 | { |
4837 | best_cost = act_cost; | |
00991688 | 4838 | |
4839 | if (best_delta) | |
4840 | iv_ca_delta_free (&best_delta); | |
4841 | best_delta = act_delta; | |
dede8dcc | 4842 | } |
00991688 | 4843 | else |
4844 | iv_ca_delta_free (&act_delta); | |
dede8dcc | 4845 | } |
4846 | } | |
4847 | ||
00991688 | 4848 | iv_ca_delta_commit (data, ivs, best_delta, true); |
4849 | iv_ca_delta_free (&best_delta); | |
dec41e98 | 4850 | |
3c2818b0 | 4851 | return !infinite_cost_p (best_cost); |
dec41e98 | 4852 | } |
4853 | ||
00991688 | 4854 | /* Finds an initial assignment of candidates to uses. */ |
dec41e98 | 4855 | |
00991688 | 4856 | static struct iv_ca * |
4857 | get_initial_solution (struct ivopts_data *data) | |
dec41e98 | 4858 | { |
00991688 | 4859 | struct iv_ca *ivs = iv_ca_new (data); |
dec41e98 | 4860 | unsigned i; |
4861 | ||
4862 | for (i = 0; i < n_iv_uses (data); i++) | |
00991688 | 4863 | if (!try_add_cand_for (data, ivs, iv_use (data, i))) |
4864 | { | |
4865 | iv_ca_free (&ivs); | |
4866 | return NULL; | |
4867 | } | |
dec41e98 | 4868 | |
00991688 | 4869 | return ivs; |
dec41e98 | 4870 | } |
4871 | ||
00991688 | 4872 | /* Tries to improve set of induction variables IVS. */ |
dec41e98 | 4873 | |
4874 | static bool | |
00991688 | 4875 | try_improve_iv_set (struct ivopts_data *data, struct iv_ca *ivs) |
dec41e98 | 4876 | { |
3c2818b0 | 4877 | unsigned i, n_ivs; |
4878 | comp_cost acost, best_cost = iv_ca_cost (ivs); | |
13ea2c1f | 4879 | struct iv_ca_delta *best_delta = NULL, *act_delta, *tmp_delta; |
00991688 | 4880 | struct iv_cand *cand; |
dec41e98 | 4881 | |
13ea2c1f | 4882 | /* Try extending the set of induction variables by one. */ |
dec41e98 | 4883 | for (i = 0; i < n_iv_cands (data); i++) |
4884 | { | |
00991688 | 4885 | cand = iv_cand (data, i); |
4886 | ||
4887 | if (iv_ca_cand_used_p (ivs, cand)) | |
13ea2c1f | 4888 | continue; |
4889 | ||
4890 | acost = iv_ca_extend (data, ivs, cand, &act_delta, &n_ivs); | |
4891 | if (!act_delta) | |
4892 | continue; | |
4893 | ||
4894 | /* If we successfully added the candidate and the set is small enough, | |
4895 | try optimizing it by removing other candidates. */ | |
4896 | if (n_ivs <= ALWAYS_PRUNE_CAND_SET_BOUND) | |
4897 | { | |
4898 | iv_ca_delta_commit (data, ivs, act_delta, true); | |
4899 | acost = iv_ca_prune (data, ivs, cand, &tmp_delta); | |
4900 | iv_ca_delta_commit (data, ivs, act_delta, false); | |
4901 | act_delta = iv_ca_delta_join (act_delta, tmp_delta); | |
4902 | } | |
dec41e98 | 4903 | |
3c2818b0 | 4904 | if (compare_costs (acost, best_cost) < 0) |
dec41e98 | 4905 | { |
00991688 | 4906 | best_cost = acost; |
13ea2c1f | 4907 | iv_ca_delta_free (&best_delta); |
00991688 | 4908 | best_delta = act_delta; |
dec41e98 | 4909 | } |
dec41e98 | 4910 | else |
00991688 | 4911 | iv_ca_delta_free (&act_delta); |
dec41e98 | 4912 | } |
4913 | ||
00991688 | 4914 | if (!best_delta) |
13ea2c1f | 4915 | { |
4916 | /* Try removing the candidates from the set instead. */ | |
4917 | best_cost = iv_ca_prune (data, ivs, NULL, &best_delta); | |
4918 | ||
4919 | /* Nothing more we can do. */ | |
4920 | if (!best_delta) | |
4921 | return false; | |
4922 | } | |
dec41e98 | 4923 | |
00991688 | 4924 | iv_ca_delta_commit (data, ivs, best_delta, true); |
3c2818b0 | 4925 | gcc_assert (compare_costs (best_cost, iv_ca_cost (ivs)) == 0); |
00991688 | 4926 | iv_ca_delta_free (&best_delta); |
dec41e98 | 4927 | return true; |
4928 | } | |
4929 | ||
4930 | /* Attempts to find the optimal set of induction variables. We do simple | |
4931 | greedy heuristic -- we try to replace at most one candidate in the selected | |
4932 | solution and remove the unused ivs while this improves the cost. */ | |
4933 | ||
00991688 | 4934 | static struct iv_ca * |
dec41e98 | 4935 | find_optimal_iv_set (struct ivopts_data *data) |
4936 | { | |
00991688 | 4937 | unsigned i; |
4938 | struct iv_ca *set; | |
dec41e98 | 4939 | struct iv_use *use; |
4940 | ||
00991688 | 4941 | /* Get the initial solution. */ |
4942 | set = get_initial_solution (data); | |
4943 | if (!set) | |
dec41e98 | 4944 | { |
4945 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4946 | fprintf (dump_file, "Unable to substitute for ivs, failed.\n"); | |
dec41e98 | 4947 | return NULL; |
4948 | } | |
4949 | ||
4950 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4951 | { | |
00991688 | 4952 | fprintf (dump_file, "Initial set of candidates:\n"); |
4953 | iv_ca_dump (data, dump_file, set); | |
dec41e98 | 4954 | } |
4955 | ||
00991688 | 4956 | while (try_improve_iv_set (data, set)) |
dec41e98 | 4957 | { |
4958 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4959 | { | |
00991688 | 4960 | fprintf (dump_file, "Improved to:\n"); |
4961 | iv_ca_dump (data, dump_file, set); | |
dec41e98 | 4962 | } |
4963 | } | |
4964 | ||
4965 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3c2818b0 | 4966 | { |
4967 | comp_cost cost = iv_ca_cost (set); | |
4968 | fprintf (dump_file, "Final cost %d (complexity %d)\n\n", cost.cost, cost.complexity); | |
4969 | } | |
dec41e98 | 4970 | |
4971 | for (i = 0; i < n_iv_uses (data); i++) | |
4972 | { | |
4973 | use = iv_use (data, i); | |
00991688 | 4974 | use->selected = iv_ca_cand_for_use (set, use)->cand; |
dec41e98 | 4975 | } |
4976 | ||
dec41e98 | 4977 | return set; |
4978 | } | |
4979 | ||
4980 | /* Creates a new induction variable corresponding to CAND. */ | |
4981 | ||
4982 | static void | |
4983 | create_new_iv (struct ivopts_data *data, struct iv_cand *cand) | |
4984 | { | |
75a70cf9 | 4985 | gimple_stmt_iterator incr_pos; |
dec41e98 | 4986 | tree base; |
4987 | bool after = false; | |
4988 | ||
4989 | if (!cand->iv) | |
4990 | return; | |
4991 | ||
4992 | switch (cand->pos) | |
4993 | { | |
4994 | case IP_NORMAL: | |
75a70cf9 | 4995 | incr_pos = gsi_last_bb (ip_normal_pos (data->current_loop)); |
dec41e98 | 4996 | break; |
4997 | ||
4998 | case IP_END: | |
75a70cf9 | 4999 | incr_pos = gsi_last_bb (ip_end_pos (data->current_loop)); |
dec41e98 | 5000 | after = true; |
5001 | break; | |
5002 | ||
5003 | case IP_ORIGINAL: | |
5004 | /* Mark that the iv is preserved. */ | |
5005 | name_info (data, cand->var_before)->preserve_biv = true; | |
5006 | name_info (data, cand->var_after)->preserve_biv = true; | |
5007 | ||
5008 | /* Rewrite the increment so that it uses var_before directly. */ | |
5009 | find_interesting_uses_op (data, cand->var_after)->selected = cand; | |
5010 | ||
5011 | return; | |
5012 | } | |
5013 | ||
5014 | gimple_add_tmp_var (cand->var_before); | |
987392e5 | 5015 | add_referenced_var (cand->var_before); |
dec41e98 | 5016 | |
5017 | base = unshare_expr (cand->iv->base); | |
5018 | ||
651874e1 | 5019 | create_iv (base, unshare_expr (cand->iv->step), |
5020 | cand->var_before, data->current_loop, | |
dec41e98 | 5021 | &incr_pos, after, &cand->var_before, &cand->var_after); |
5022 | } | |
5023 | ||
5024 | /* Creates new induction variables described in SET. */ | |
5025 | ||
5026 | static void | |
00991688 | 5027 | create_new_ivs (struct ivopts_data *data, struct iv_ca *set) |
dec41e98 | 5028 | { |
5029 | unsigned i; | |
5030 | struct iv_cand *cand; | |
0cc4271a | 5031 | bitmap_iterator bi; |
dec41e98 | 5032 | |
00991688 | 5033 | EXECUTE_IF_SET_IN_BITMAP (set->cands, 0, i, bi) |
dec41e98 | 5034 | { |
5035 | cand = iv_cand (data, i); | |
5036 | create_new_iv (data, cand); | |
0cc4271a | 5037 | } |
dec41e98 | 5038 | } |
5039 | ||
255b6be7 | 5040 | /* Returns the phi-node in BB with result RESULT. */ |
5041 | ||
5042 | static gimple | |
5043 | get_phi_with_result (basic_block bb, tree result) | |
5044 | { | |
5045 | gimple_stmt_iterator i = gsi_start_phis (bb); | |
5046 | ||
5047 | for (; !gsi_end_p (i); gsi_next (&i)) | |
5048 | if (gimple_phi_result (gsi_stmt (i)) == result) | |
5049 | return gsi_stmt (i); | |
5050 | ||
5051 | gcc_unreachable (); | |
5052 | return NULL; | |
5053 | } | |
5054 | ||
5055 | ||
dec41e98 | 5056 | /* Removes statement STMT (real or a phi node). If INCLUDING_DEFINED_NAME |
5057 | is true, remove also the ssa name defined by the statement. */ | |
5058 | ||
5059 | static void | |
75a70cf9 | 5060 | remove_statement (gimple stmt, bool including_defined_name) |
dec41e98 | 5061 | { |
75a70cf9 | 5062 | if (gimple_code (stmt) == GIMPLE_PHI) |
255b6be7 | 5063 | { |
5064 | gimple bb_phi = get_phi_with_result (gimple_bb (stmt), | |
5065 | gimple_phi_result (stmt)); | |
5066 | gimple_stmt_iterator bsi = gsi_for_stmt (bb_phi); | |
5067 | remove_phi_node (&bsi, including_defined_name); | |
5068 | } | |
dec41e98 | 5069 | else |
5070 | { | |
255b6be7 | 5071 | gimple_stmt_iterator bsi = gsi_for_stmt (stmt); |
75a70cf9 | 5072 | gsi_remove (&bsi, true); |
8d9f686b | 5073 | release_defs (stmt); |
dec41e98 | 5074 | } |
5075 | } | |
5076 | ||
5077 | /* Rewrites USE (definition of iv used in a nonlinear expression) | |
5078 | using candidate CAND. */ | |
5079 | ||
5080 | static void | |
5081 | rewrite_use_nonlinear_expr (struct ivopts_data *data, | |
5082 | struct iv_use *use, struct iv_cand *cand) | |
5083 | { | |
99e833c3 | 5084 | tree comp; |
75a70cf9 | 5085 | tree op, tgt; |
5086 | gimple ass; | |
5087 | gimple_stmt_iterator bsi; | |
99e833c3 | 5088 | |
5089 | /* An important special case -- if we are asked to express value of | |
5090 | the original iv by itself, just exit; there is no need to | |
5091 | introduce a new computation (that might also need casting the | |
5092 | variable to unsigned and back). */ | |
5093 | if (cand->pos == IP_ORIGINAL | |
c0b52952 | 5094 | && cand->incremented_at == use->stmt) |
99e833c3 | 5095 | { |
c0b52952 | 5096 | tree step, ctype, utype; |
75a70cf9 | 5097 | enum tree_code incr_code = PLUS_EXPR, old_code; |
c0b52952 | 5098 | |
75a70cf9 | 5099 | gcc_assert (is_gimple_assign (use->stmt)); |
5100 | gcc_assert (gimple_assign_lhs (use->stmt) == cand->var_after); | |
c0b52952 | 5101 | |
5102 | step = cand->iv->step; | |
5103 | ctype = TREE_TYPE (step); | |
5104 | utype = TREE_TYPE (cand->var_after); | |
5105 | if (TREE_CODE (step) == NEGATE_EXPR) | |
5106 | { | |
5107 | incr_code = MINUS_EXPR; | |
5108 | step = TREE_OPERAND (step, 0); | |
5109 | } | |
5110 | ||
5111 | /* Check whether we may leave the computation unchanged. | |
5112 | This is the case only if it does not rely on other | |
5113 | computations in the loop -- otherwise, the computation | |
5114 | we rely upon may be removed in remove_unused_ivs, | |
5115 | thus leading to ICE. */ | |
75a70cf9 | 5116 | old_code = gimple_assign_rhs_code (use->stmt); |
5117 | if (old_code == PLUS_EXPR | |
5118 | || old_code == MINUS_EXPR | |
5119 | || old_code == POINTER_PLUS_EXPR) | |
c0b52952 | 5120 | { |
75a70cf9 | 5121 | if (gimple_assign_rhs1 (use->stmt) == cand->var_before) |
5122 | op = gimple_assign_rhs2 (use->stmt); | |
5123 | else if (old_code != MINUS_EXPR | |
5124 | && gimple_assign_rhs2 (use->stmt) == cand->var_before) | |
5125 | op = gimple_assign_rhs1 (use->stmt); | |
c0b52952 | 5126 | else |
5127 | op = NULL_TREE; | |
5128 | } | |
5129 | else | |
5130 | op = NULL_TREE; | |
99e833c3 | 5131 | |
c0b52952 | 5132 | if (op |
5133 | && (TREE_CODE (op) == INTEGER_CST | |
5134 | || operand_equal_p (op, step, 0))) | |
99e833c3 | 5135 | return; |
c0b52952 | 5136 | |
5137 | /* Otherwise, add the necessary computations to express | |
5138 | the iv. */ | |
5139 | op = fold_convert (ctype, cand->var_before); | |
5140 | comp = fold_convert (utype, | |
5141 | build2 (incr_code, ctype, op, | |
5142 | unshare_expr (step))); | |
99e833c3 | 5143 | } |
c0b52952 | 5144 | else |
d3610bea | 5145 | { |
5146 | comp = get_computation (data->current_loop, use, cand); | |
5147 | gcc_assert (comp != NULL_TREE); | |
5148 | } | |
99e833c3 | 5149 | |
75a70cf9 | 5150 | switch (gimple_code (use->stmt)) |
dec41e98 | 5151 | { |
75a70cf9 | 5152 | case GIMPLE_PHI: |
dec41e98 | 5153 | tgt = PHI_RESULT (use->stmt); |
5154 | ||
5155 | /* If we should keep the biv, do not replace it. */ | |
5156 | if (name_info (data, tgt)->preserve_biv) | |
5157 | return; | |
5158 | ||
75a70cf9 | 5159 | bsi = gsi_after_labels (gimple_bb (use->stmt)); |
8c0963c4 | 5160 | break; |
5161 | ||
75a70cf9 | 5162 | case GIMPLE_ASSIGN: |
5163 | tgt = gimple_assign_lhs (use->stmt); | |
5164 | bsi = gsi_for_stmt (use->stmt); | |
8c0963c4 | 5165 | break; |
5166 | ||
5167 | default: | |
5168 | gcc_unreachable (); | |
dec41e98 | 5169 | } |
dec41e98 | 5170 | |
75a70cf9 | 5171 | op = force_gimple_operand_gsi (&bsi, comp, false, SSA_NAME_VAR (tgt), |
5172 | true, GSI_SAME_STMT); | |
dec41e98 | 5173 | |
75a70cf9 | 5174 | if (gimple_code (use->stmt) == GIMPLE_PHI) |
dec41e98 | 5175 | { |
75a70cf9 | 5176 | ass = gimple_build_assign (tgt, op); |
5177 | gsi_insert_before (&bsi, ass, GSI_SAME_STMT); | |
dec41e98 | 5178 | remove_statement (use->stmt, false); |
dec41e98 | 5179 | } |
5180 | else | |
75a70cf9 | 5181 | { |
5182 | gimple_assign_set_rhs_from_tree (&bsi, op); | |
5183 | use->stmt = gsi_stmt (bsi); | |
5184 | } | |
dec41e98 | 5185 | } |
5186 | ||
5187 | /* Replaces ssa name in index IDX by its basic variable. Callback for | |
5188 | for_each_index. */ | |
5189 | ||
5190 | static bool | |
a59824bb | 5191 | idx_remove_ssa_names (tree base, tree *idx, |
dec41e98 | 5192 | void *data ATTRIBUTE_UNUSED) |
5193 | { | |
a59824bb | 5194 | tree *op; |
5195 | ||
dec41e98 | 5196 | if (TREE_CODE (*idx) == SSA_NAME) |
5197 | *idx = SSA_NAME_VAR (*idx); | |
a59824bb | 5198 | |
5e19919e | 5199 | if (TREE_CODE (base) == ARRAY_REF || TREE_CODE (base) == ARRAY_RANGE_REF) |
a59824bb | 5200 | { |
5201 | op = &TREE_OPERAND (base, 2); | |
5202 | if (*op | |
5203 | && TREE_CODE (*op) == SSA_NAME) | |
5204 | *op = SSA_NAME_VAR (*op); | |
5205 | op = &TREE_OPERAND (base, 3); | |
5206 | if (*op | |
5207 | && TREE_CODE (*op) == SSA_NAME) | |
5208 | *op = SSA_NAME_VAR (*op); | |
5209 | } | |
5210 | ||
dec41e98 | 5211 | return true; |
5212 | } | |
5213 | ||
5214 | /* Unshares REF and replaces ssa names inside it by their basic variables. */ | |
5215 | ||
5216 | static tree | |
5217 | unshare_and_remove_ssa_names (tree ref) | |
5218 | { | |
5219 | ref = unshare_expr (ref); | |
5220 | for_each_index (&ref, idx_remove_ssa_names, NULL); | |
5221 | ||
5222 | return ref; | |
5223 | } | |
5224 | ||
aed164c3 | 5225 | /* Copies the reference information from OLD_REF to NEW_REF. */ |
88dbf20f | 5226 | |
aed164c3 | 5227 | static void |
5228 | copy_ref_info (tree new_ref, tree old_ref) | |
5229 | { | |
5230 | if (TREE_CODE (old_ref) == TARGET_MEM_REF) | |
5231 | copy_mem_ref_info (new_ref, old_ref); | |
5232 | else | |
dd277d48 | 5233 | TMR_ORIGINAL (new_ref) = unshare_and_remove_ssa_names (old_ref); |
dec41e98 | 5234 | } |
5235 | ||
5236 | /* Rewrites USE (address that is an iv) using candidate CAND. */ | |
5237 | ||
5238 | static void | |
5239 | rewrite_use_address (struct ivopts_data *data, | |
5240 | struct iv_use *use, struct iv_cand *cand) | |
5241 | { | |
d3610bea | 5242 | aff_tree aff; |
75a70cf9 | 5243 | gimple_stmt_iterator bsi = gsi_for_stmt (use->stmt); |
aed164c3 | 5244 | tree ref; |
d3610bea | 5245 | bool ok; |
dec41e98 | 5246 | |
d3610bea | 5247 | ok = get_computation_aff (data->current_loop, use, cand, use->stmt, &aff); |
5248 | gcc_assert (ok); | |
aed164c3 | 5249 | unshare_aff_combination (&aff); |
dec41e98 | 5250 | |
f529eb25 | 5251 | ref = create_mem_ref (&bsi, TREE_TYPE (*use->op_p), &aff, data->speed); |
aed164c3 | 5252 | copy_ref_info (ref, *use->op_p); |
5253 | *use->op_p = ref; | |
dec41e98 | 5254 | } |
5255 | ||
5256 | /* Rewrites USE (the condition such that one of the arguments is an iv) using | |
5257 | candidate CAND. */ | |
5258 | ||
5259 | static void | |
5260 | rewrite_use_compare (struct ivopts_data *data, | |
5261 | struct iv_use *use, struct iv_cand *cand) | |
5262 | { | |
02f8cd87 | 5263 | tree comp, *var_p, op, bound; |
75a70cf9 | 5264 | gimple_stmt_iterator bsi = gsi_for_stmt (use->stmt); |
dec41e98 | 5265 | enum tree_code compare; |
c4d3b428 | 5266 | struct cost_pair *cp = get_use_iv_cost (data, use, cand); |
02f8cd87 | 5267 | bool ok; |
5268 | ||
c4d3b428 | 5269 | bound = cp->value; |
5270 | if (bound) | |
dec41e98 | 5271 | { |
34bbbd2e | 5272 | tree var = var_at_stmt (data->current_loop, cand, use->stmt); |
5273 | tree var_type = TREE_TYPE (var); | |
b718fe63 | 5274 | gimple_seq stmts; |
34bbbd2e | 5275 | |
c4d3b428 | 5276 | compare = iv_elimination_compare (data, use); |
02f8cd87 | 5277 | bound = unshare_expr (fold_convert (var_type, bound)); |
b718fe63 | 5278 | op = force_gimple_operand (bound, &stmts, true, NULL_TREE); |
5279 | if (stmts) | |
5280 | gsi_insert_seq_on_edge_immediate ( | |
5281 | loop_preheader_edge (data->current_loop), | |
5282 | stmts); | |
dec41e98 | 5283 | |
75a70cf9 | 5284 | gimple_cond_set_lhs (use->stmt, var); |
5285 | gimple_cond_set_code (use->stmt, compare); | |
5286 | gimple_cond_set_rhs (use->stmt, op); | |
dec41e98 | 5287 | return; |
5288 | } | |
5289 | ||
5290 | /* The induction variable elimination failed; just express the original | |
5291 | giv. */ | |
aed164c3 | 5292 | comp = get_computation (data->current_loop, use, cand); |
d3610bea | 5293 | gcc_assert (comp != NULL_TREE); |
dec41e98 | 5294 | |
75a70cf9 | 5295 | ok = extract_cond_operands (data, use->stmt, &var_p, NULL, NULL, NULL); |
02f8cd87 | 5296 | gcc_assert (ok); |
dec41e98 | 5297 | |
75a70cf9 | 5298 | *var_p = force_gimple_operand_gsi (&bsi, comp, true, SSA_NAME_VAR (*var_p), |
5299 | true, GSI_SAME_STMT); | |
dec41e98 | 5300 | } |
5301 | ||
dec41e98 | 5302 | /* Rewrites USE using candidate CAND. */ |
5303 | ||
5304 | static void | |
de6ed584 | 5305 | rewrite_use (struct ivopts_data *data, struct iv_use *use, struct iv_cand *cand) |
dec41e98 | 5306 | { |
de6ed584 | 5307 | push_stmt_changes (&use->stmt); |
5308 | ||
dec41e98 | 5309 | switch (use->type) |
5310 | { | |
5311 | case USE_NONLINEAR_EXPR: | |
5312 | rewrite_use_nonlinear_expr (data, use, cand); | |
5313 | break; | |
5314 | ||
dec41e98 | 5315 | case USE_ADDRESS: |
5316 | rewrite_use_address (data, use, cand); | |
5317 | break; | |
5318 | ||
5319 | case USE_COMPARE: | |
5320 | rewrite_use_compare (data, use, cand); | |
5321 | break; | |
5322 | ||
5323 | default: | |
8c0963c4 | 5324 | gcc_unreachable (); |
dec41e98 | 5325 | } |
de6ed584 | 5326 | |
5327 | pop_stmt_changes (&use->stmt); | |
dec41e98 | 5328 | } |
5329 | ||
5330 | /* Rewrite the uses using the selected induction variables. */ | |
5331 | ||
5332 | static void | |
5333 | rewrite_uses (struct ivopts_data *data) | |
5334 | { | |
5335 | unsigned i; | |
5336 | struct iv_cand *cand; | |
5337 | struct iv_use *use; | |
5338 | ||
5339 | for (i = 0; i < n_iv_uses (data); i++) | |
5340 | { | |
5341 | use = iv_use (data, i); | |
5342 | cand = use->selected; | |
8c0963c4 | 5343 | gcc_assert (cand); |
dec41e98 | 5344 | |
5345 | rewrite_use (data, use, cand); | |
5346 | } | |
5347 | } | |
5348 | ||
5349 | /* Removes the ivs that are not used after rewriting. */ | |
5350 | ||
5351 | static void | |
5352 | remove_unused_ivs (struct ivopts_data *data) | |
5353 | { | |
5354 | unsigned j; | |
0cc4271a | 5355 | bitmap_iterator bi; |
dec41e98 | 5356 | |
0cc4271a | 5357 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, j, bi) |
dec41e98 | 5358 | { |
5359 | struct version_info *info; | |
5360 | ||
5361 | info = ver_info (data, j); | |
5362 | if (info->iv | |
7a973feb | 5363 | && !integer_zerop (info->iv->step) |
dec41e98 | 5364 | && !info->inv_id |
5365 | && !info->iv->have_use_for | |
5366 | && !info->preserve_biv) | |
5367 | remove_statement (SSA_NAME_DEF_STMT (info->iv->ssa_name), true); | |
0cc4271a | 5368 | } |
dec41e98 | 5369 | } |
5370 | ||
5371 | /* Frees data allocated by the optimization of a single loop. */ | |
5372 | ||
5373 | static void | |
5374 | free_loop_data (struct ivopts_data *data) | |
5375 | { | |
5376 | unsigned i, j; | |
0cc4271a | 5377 | bitmap_iterator bi; |
7d18ea07 | 5378 | tree obj; |
dec41e98 | 5379 | |
b30a8715 | 5380 | if (data->niters) |
5381 | { | |
5382 | pointer_map_destroy (data->niters); | |
5383 | data->niters = NULL; | |
5384 | } | |
b091dc59 | 5385 | |
0cc4271a | 5386 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
dec41e98 | 5387 | { |
5388 | struct version_info *info; | |
5389 | ||
5390 | info = ver_info (data, i); | |
5391 | if (info->iv) | |
5392 | free (info->iv); | |
5393 | info->iv = NULL; | |
5394 | info->has_nonlin_use = false; | |
5395 | info->preserve_biv = false; | |
5396 | info->inv_id = 0; | |
0cc4271a | 5397 | } |
dec41e98 | 5398 | bitmap_clear (data->relevant); |
00991688 | 5399 | bitmap_clear (data->important_candidates); |
dec41e98 | 5400 | |
5401 | for (i = 0; i < n_iv_uses (data); i++) | |
5402 | { | |
5403 | struct iv_use *use = iv_use (data, i); | |
5404 | ||
5405 | free (use->iv); | |
27335ffd | 5406 | BITMAP_FREE (use->related_cands); |
dec41e98 | 5407 | for (j = 0; j < use->n_map_members; j++) |
5408 | if (use->cost_map[j].depends_on) | |
27335ffd | 5409 | BITMAP_FREE (use->cost_map[j].depends_on); |
dec41e98 | 5410 | free (use->cost_map); |
5411 | free (use); | |
5412 | } | |
7d18ea07 | 5413 | VEC_truncate (iv_use_p, data->iv_uses, 0); |
dec41e98 | 5414 | |
5415 | for (i = 0; i < n_iv_cands (data); i++) | |
5416 | { | |
5417 | struct iv_cand *cand = iv_cand (data, i); | |
5418 | ||
5419 | if (cand->iv) | |
5420 | free (cand->iv); | |
651874e1 | 5421 | if (cand->depends_on) |
5422 | BITMAP_FREE (cand->depends_on); | |
dec41e98 | 5423 | free (cand); |
5424 | } | |
7d18ea07 | 5425 | VEC_truncate (iv_cand_p, data->iv_candidates, 0); |
dec41e98 | 5426 | |
5427 | if (data->version_info_size < num_ssa_names) | |
5428 | { | |
5429 | data->version_info_size = 2 * num_ssa_names; | |
5430 | free (data->version_info); | |
4c36ffe6 | 5431 | data->version_info = XCNEWVEC (struct version_info, data->version_info_size); |
dec41e98 | 5432 | } |
5433 | ||
5434 | data->max_inv_id = 0; | |
5435 | ||
7d18ea07 | 5436 | for (i = 0; VEC_iterate (tree, decl_rtl_to_reset, i, obj); i++) |
5437 | SET_DECL_RTL (obj, NULL_RTX); | |
dec41e98 | 5438 | |
7d18ea07 | 5439 | VEC_truncate (tree, decl_rtl_to_reset, 0); |
dec41e98 | 5440 | } |
5441 | ||
5442 | /* Finalizes data structures used by the iv optimization pass. LOOPS is the | |
5443 | loop tree. */ | |
5444 | ||
5445 | static void | |
fe382241 | 5446 | tree_ssa_iv_optimize_finalize (struct ivopts_data *data) |
dec41e98 | 5447 | { |
dec41e98 | 5448 | free_loop_data (data); |
5449 | free (data->version_info); | |
27335ffd | 5450 | BITMAP_FREE (data->relevant); |
5451 | BITMAP_FREE (data->important_candidates); | |
dec41e98 | 5452 | |
7d18ea07 | 5453 | VEC_free (tree, heap, decl_rtl_to_reset); |
5454 | VEC_free (iv_use_p, heap, data->iv_uses); | |
5455 | VEC_free (iv_cand_p, heap, data->iv_candidates); | |
dec41e98 | 5456 | } |
5457 | ||
5458 | /* Optimizes the LOOP. Returns true if anything changed. */ | |
5459 | ||
5460 | static bool | |
5461 | tree_ssa_iv_optimize_loop (struct ivopts_data *data, struct loop *loop) | |
5462 | { | |
5463 | bool changed = false; | |
00991688 | 5464 | struct iv_ca *iv_ca; |
dec41e98 | 5465 | edge exit; |
5466 | ||
b30a8715 | 5467 | gcc_assert (!data->niters); |
dec41e98 | 5468 | data->current_loop = loop; |
f529eb25 | 5469 | data->speed = optimize_loop_for_speed_p (loop); |
dec41e98 | 5470 | |
5471 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
5472 | { | |
5473 | fprintf (dump_file, "Processing loop %d\n", loop->num); | |
5474 | ||
5475 | exit = single_dom_exit (loop); | |
5476 | if (exit) | |
5477 | { | |
5478 | fprintf (dump_file, " single exit %d -> %d, exit condition ", | |
5479 | exit->src->index, exit->dest->index); | |
75a70cf9 | 5480 | print_gimple_stmt (dump_file, last_stmt (exit->src), 0, TDF_SLIM); |
dec41e98 | 5481 | fprintf (dump_file, "\n"); |
5482 | } | |
5483 | ||
5484 | fprintf (dump_file, "\n"); | |
5485 | } | |
5486 | ||
5487 | /* For each ssa name determines whether it behaves as an induction variable | |
5488 | in some loop. */ | |
5489 | if (!find_induction_variables (data)) | |
5490 | goto finish; | |
5491 | ||
5492 | /* Finds interesting uses (item 1). */ | |
5493 | find_interesting_uses (data); | |
5494 | if (n_iv_uses (data) > MAX_CONSIDERED_USES) | |
5495 | goto finish; | |
5496 | ||
5497 | /* Finds candidates for the induction variables (item 2). */ | |
5498 | find_iv_candidates (data); | |
5499 | ||
5500 | /* Calculates the costs (item 3, part 1). */ | |
5501 | determine_use_iv_costs (data); | |
5502 | determine_iv_costs (data); | |
5503 | determine_set_costs (data); | |
5504 | ||
5505 | /* Find the optimal set of induction variables (item 3, part 2). */ | |
00991688 | 5506 | iv_ca = find_optimal_iv_set (data); |
5507 | if (!iv_ca) | |
dec41e98 | 5508 | goto finish; |
5509 | changed = true; | |
5510 | ||
5511 | /* Create the new induction variables (item 4, part 1). */ | |
00991688 | 5512 | create_new_ivs (data, iv_ca); |
5513 | iv_ca_free (&iv_ca); | |
dec41e98 | 5514 | |
5515 | /* Rewrite the uses (item 4, part 2). */ | |
5516 | rewrite_uses (data); | |
5517 | ||
5518 | /* Remove the ivs that are unused after rewriting. */ | |
5519 | remove_unused_ivs (data); | |
5520 | ||
dec41e98 | 5521 | /* We have changed the structure of induction variables; it might happen |
5522 | that definitions in the scev database refer to some of them that were | |
5523 | eliminated. */ | |
5524 | scev_reset (); | |
5525 | ||
5526 | finish: | |
5527 | free_loop_data (data); | |
5528 | ||
5529 | return changed; | |
5530 | } | |
5531 | ||
7194de72 | 5532 | /* Main entry point. Optimizes induction variables in loops. */ |
dec41e98 | 5533 | |
5534 | void | |
7194de72 | 5535 | tree_ssa_iv_optimize (void) |
dec41e98 | 5536 | { |
5537 | struct loop *loop; | |
5538 | struct ivopts_data data; | |
17519ba0 | 5539 | loop_iterator li; |
dec41e98 | 5540 | |
fe382241 | 5541 | tree_ssa_iv_optimize_init (&data); |
dec41e98 | 5542 | |
5543 | /* Optimize the loops starting with the innermost ones. */ | |
17519ba0 | 5544 | FOR_EACH_LOOP (li, loop, LI_FROM_INNERMOST) |
dec41e98 | 5545 | { |
abf7e53a | 5546 | if (dump_file && (dump_flags & TDF_DETAILS)) |
5547 | flow_loop_dump (loop, dump_file, NULL, 1); | |
0e269eea | 5548 | |
5549 | tree_ssa_iv_optimize_loop (&data, loop); | |
dec41e98 | 5550 | } |
5551 | ||
fe382241 | 5552 | tree_ssa_iv_optimize_finalize (&data); |
dec41e98 | 5553 | } |