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8b11a64c | 1 | /* Induction variable optimizations. |
ad616de1 | 2 | Copyright (C) 2003, 2004, 2005 Free Software Foundation, Inc. |
8b11a64c ZD |
3 | |
4 | This file is part of GCC. | |
5 | ||
6 | GCC is free software; you can redistribute it and/or modify it | |
7 | under the terms of the GNU General Public License as published by the | |
8 | Free Software Foundation; either version 2, or (at your option) any | |
9 | later version. | |
10 | ||
11 | GCC is distributed in the hope that it will be useful, but WITHOUT | |
12 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GCC; see the file COPYING. If not, write to the Free | |
18 | Software Foundation, 59 Temple Place - Suite 330, Boston, MA | |
19 | 02111-1307, USA. */ | |
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" | |
86 | #include "hashtab.h" | |
87 | #include "tree-chrec.h" | |
88 | #include "tree-scalar-evolution.h" | |
89 | #include "cfgloop.h" | |
90 | #include "params.h" | |
39b4020c | 91 | #include "langhooks.h" |
8b11a64c ZD |
92 | |
93 | /* The infinite cost. */ | |
94 | #define INFTY 10000000 | |
95 | ||
96 | /* The expected number of loop iterations. TODO -- use profiling instead of | |
97 | this. */ | |
98 | #define AVG_LOOP_NITER(LOOP) 5 | |
99 | ||
8b11a64c ZD |
100 | |
101 | /* Representation of the induction variable. */ | |
102 | struct iv | |
103 | { | |
104 | tree base; /* Initial value of the iv. */ | |
e6845c23 | 105 | tree base_object; /* A memory object to that the induction variable points. */ |
8b11a64c ZD |
106 | tree step; /* Step of the iv (constant only). */ |
107 | tree ssa_name; /* The ssa name with the value. */ | |
108 | bool biv_p; /* Is it a biv? */ | |
109 | bool have_use_for; /* Do we already have a use for it? */ | |
110 | unsigned use_id; /* The identifier in the use if it is the case. */ | |
111 | }; | |
112 | ||
113 | /* Per-ssa version information (induction variable descriptions, etc.). */ | |
114 | struct version_info | |
115 | { | |
116 | tree name; /* The ssa name. */ | |
117 | struct iv *iv; /* Induction variable description. */ | |
118 | bool has_nonlin_use; /* For a loop-level invariant, whether it is used in | |
119 | an expression that is not an induction variable. */ | |
120 | unsigned inv_id; /* Id of an invariant. */ | |
121 | bool preserve_biv; /* For the original biv, whether to preserve it. */ | |
122 | }; | |
123 | ||
124 | /* Information attached to loop. */ | |
125 | struct loop_data | |
126 | { | |
8b11a64c ZD |
127 | unsigned regs_used; /* Number of registers used. */ |
128 | }; | |
129 | ||
130 | /* Types of uses. */ | |
131 | enum use_type | |
132 | { | |
133 | USE_NONLINEAR_EXPR, /* Use in a nonlinear expression. */ | |
134 | USE_OUTER, /* The induction variable is used outside the loop. */ | |
135 | USE_ADDRESS, /* Use in an address. */ | |
136 | USE_COMPARE /* Use is a compare. */ | |
137 | }; | |
138 | ||
139 | /* The candidate - cost pair. */ | |
140 | struct cost_pair | |
141 | { | |
142 | struct iv_cand *cand; /* The candidate. */ | |
143 | unsigned cost; /* The cost. */ | |
144 | bitmap depends_on; /* The list of invariants that have to be | |
145 | preserved. */ | |
f5f12961 ZD |
146 | tree value; /* For final value elimination, the expression for |
147 | the final value of the iv. For iv elimination, | |
148 | the new bound to compare with. */ | |
8b11a64c ZD |
149 | }; |
150 | ||
151 | /* Use. */ | |
152 | struct iv_use | |
153 | { | |
154 | unsigned id; /* The id of the use. */ | |
155 | enum use_type type; /* Type of the use. */ | |
156 | struct iv *iv; /* The induction variable it is based on. */ | |
157 | tree stmt; /* Statement in that it occurs. */ | |
158 | tree *op_p; /* The place where it occurs. */ | |
b1b02be2 ZD |
159 | bitmap related_cands; /* The set of "related" iv candidates, plus the common |
160 | important ones. */ | |
8b11a64c ZD |
161 | |
162 | unsigned n_map_members; /* Number of candidates in the cost_map list. */ | |
163 | struct cost_pair *cost_map; | |
164 | /* The costs wrto the iv candidates. */ | |
165 | ||
166 | struct iv_cand *selected; | |
167 | /* The selected candidate. */ | |
168 | }; | |
169 | ||
170 | /* The position where the iv is computed. */ | |
171 | enum iv_position | |
172 | { | |
173 | IP_NORMAL, /* At the end, just before the exit condition. */ | |
174 | IP_END, /* At the end of the latch block. */ | |
175 | IP_ORIGINAL /* The original biv. */ | |
176 | }; | |
177 | ||
178 | /* The induction variable candidate. */ | |
179 | struct iv_cand | |
180 | { | |
181 | unsigned id; /* The number of the candidate. */ | |
182 | bool important; /* Whether this is an "important" candidate, i.e. such | |
183 | that it should be considered by all uses. */ | |
184 | enum iv_position pos; /* Where it is computed. */ | |
185 | tree incremented_at; /* For original biv, the statement where it is | |
186 | incremented. */ | |
187 | tree var_before; /* The variable used for it before increment. */ | |
188 | tree var_after; /* The variable used for it after increment. */ | |
189 | struct iv *iv; /* The value of the candidate. NULL for | |
190 | "pseudocandidate" used to indicate the possibility | |
191 | to replace the final value of an iv by direct | |
192 | computation of the value. */ | |
193 | unsigned cost; /* Cost of the candidate. */ | |
9be872b7 ZD |
194 | bitmap depends_on; /* The list of invariants that are used in step of the |
195 | biv. */ | |
8b11a64c ZD |
196 | }; |
197 | ||
198 | /* The data used by the induction variable optimizations. */ | |
199 | ||
69ebd99d KH |
200 | typedef struct iv_use *iv_use_p; |
201 | DEF_VEC_P(iv_use_p); | |
202 | DEF_VEC_ALLOC_P(iv_use_p,heap); | |
203 | ||
204 | typedef struct iv_cand *iv_cand_p; | |
205 | DEF_VEC_P(iv_cand_p); | |
206 | DEF_VEC_ALLOC_P(iv_cand_p,heap); | |
207 | ||
8b11a64c ZD |
208 | struct ivopts_data |
209 | { | |
210 | /* The currently optimized loop. */ | |
211 | struct loop *current_loop; | |
212 | ||
ca4c3169 ZD |
213 | /* Numbers of iterations for all exits of the current loop. */ |
214 | htab_t niters; | |
215 | ||
8b11a64c ZD |
216 | /* The size of version_info array allocated. */ |
217 | unsigned version_info_size; | |
218 | ||
219 | /* The array of information for the ssa names. */ | |
220 | struct version_info *version_info; | |
221 | ||
222 | /* The bitmap of indices in version_info whose value was changed. */ | |
223 | bitmap relevant; | |
224 | ||
225 | /* The maximum invariant id. */ | |
226 | unsigned max_inv_id; | |
227 | ||
228 | /* The uses of induction variables. */ | |
69ebd99d | 229 | VEC(iv_use_p,heap) *iv_uses; |
8b11a64c ZD |
230 | |
231 | /* The candidates. */ | |
69ebd99d | 232 | VEC(iv_cand_p,heap) *iv_candidates; |
8b11a64c | 233 | |
80cad5fa ZD |
234 | /* A bitmap of important candidates. */ |
235 | bitmap important_candidates; | |
236 | ||
8b11a64c ZD |
237 | /* Whether to consider just related and important candidates when replacing a |
238 | use. */ | |
239 | bool consider_all_candidates; | |
240 | }; | |
241 | ||
b1b02be2 ZD |
242 | /* An assignment of iv candidates to uses. */ |
243 | ||
244 | struct iv_ca | |
245 | { | |
246 | /* The number of uses covered by the assignment. */ | |
247 | unsigned upto; | |
248 | ||
249 | /* Number of uses that cannot be expressed by the candidates in the set. */ | |
250 | unsigned bad_uses; | |
251 | ||
252 | /* Candidate assigned to a use, together with the related costs. */ | |
253 | struct cost_pair **cand_for_use; | |
254 | ||
255 | /* Number of times each candidate is used. */ | |
256 | unsigned *n_cand_uses; | |
257 | ||
258 | /* The candidates used. */ | |
259 | bitmap cands; | |
260 | ||
36f5ada1 ZD |
261 | /* The number of candidates in the set. */ |
262 | unsigned n_cands; | |
263 | ||
b1b02be2 ZD |
264 | /* Total number of registers needed. */ |
265 | unsigned n_regs; | |
266 | ||
267 | /* Total cost of expressing uses. */ | |
268 | unsigned cand_use_cost; | |
269 | ||
270 | /* Total cost of candidates. */ | |
271 | unsigned cand_cost; | |
272 | ||
273 | /* Number of times each invariant is used. */ | |
274 | unsigned *n_invariant_uses; | |
275 | ||
276 | /* Total cost of the assignment. */ | |
277 | unsigned cost; | |
278 | }; | |
279 | ||
280 | /* Difference of two iv candidate assignments. */ | |
281 | ||
282 | struct iv_ca_delta | |
283 | { | |
284 | /* Changed use. */ | |
285 | struct iv_use *use; | |
286 | ||
287 | /* An old assignment (for rollback purposes). */ | |
288 | struct cost_pair *old_cp; | |
289 | ||
290 | /* A new assignment. */ | |
291 | struct cost_pair *new_cp; | |
292 | ||
293 | /* Next change in the list. */ | |
294 | struct iv_ca_delta *next_change; | |
295 | }; | |
296 | ||
8b11a64c ZD |
297 | /* Bound on number of candidates below that all candidates are considered. */ |
298 | ||
299 | #define CONSIDER_ALL_CANDIDATES_BOUND \ | |
300 | ((unsigned) PARAM_VALUE (PARAM_IV_CONSIDER_ALL_CANDIDATES_BOUND)) | |
301 | ||
2a7e31df | 302 | /* If there are more iv occurrences, we just give up (it is quite unlikely that |
8b11a64c ZD |
303 | optimizing such a loop would help, and it would take ages). */ |
304 | ||
305 | #define MAX_CONSIDERED_USES \ | |
306 | ((unsigned) PARAM_VALUE (PARAM_IV_MAX_CONSIDERED_USES)) | |
307 | ||
36f5ada1 ZD |
308 | /* If there are at most this number of ivs in the set, try removing unnecessary |
309 | ivs from the set always. */ | |
310 | ||
311 | #define ALWAYS_PRUNE_CAND_SET_BOUND \ | |
312 | ((unsigned) PARAM_VALUE (PARAM_IV_ALWAYS_PRUNE_CAND_SET_BOUND)) | |
313 | ||
8b11a64c ZD |
314 | /* The list of trees for that the decl_rtl field must be reset is stored |
315 | here. */ | |
316 | ||
69ebd99d | 317 | static VEC(tree,heap) *decl_rtl_to_reset; |
8b11a64c ZD |
318 | |
319 | /* Number of uses recorded in DATA. */ | |
320 | ||
321 | static inline unsigned | |
322 | n_iv_uses (struct ivopts_data *data) | |
323 | { | |
69ebd99d | 324 | return VEC_length (iv_use_p, data->iv_uses); |
8b11a64c ZD |
325 | } |
326 | ||
327 | /* Ith use recorded in DATA. */ | |
328 | ||
329 | static inline struct iv_use * | |
330 | iv_use (struct ivopts_data *data, unsigned i) | |
331 | { | |
69ebd99d | 332 | return VEC_index (iv_use_p, data->iv_uses, i); |
8b11a64c ZD |
333 | } |
334 | ||
335 | /* Number of candidates recorded in DATA. */ | |
336 | ||
337 | static inline unsigned | |
338 | n_iv_cands (struct ivopts_data *data) | |
339 | { | |
69ebd99d | 340 | return VEC_length (iv_cand_p, data->iv_candidates); |
8b11a64c ZD |
341 | } |
342 | ||
343 | /* Ith candidate recorded in DATA. */ | |
344 | ||
345 | static inline struct iv_cand * | |
346 | iv_cand (struct ivopts_data *data, unsigned i) | |
347 | { | |
69ebd99d | 348 | return VEC_index (iv_cand_p, data->iv_candidates, i); |
8b11a64c ZD |
349 | } |
350 | ||
351 | /* The data for LOOP. */ | |
352 | ||
353 | static inline struct loop_data * | |
354 | loop_data (struct loop *loop) | |
355 | { | |
356 | return loop->aux; | |
357 | } | |
358 | ||
359 | /* The single loop exit if it dominates the latch, NULL otherwise. */ | |
360 | ||
361 | static edge | |
362 | single_dom_exit (struct loop *loop) | |
363 | { | |
364 | edge exit = loop->single_exit; | |
365 | ||
366 | if (!exit) | |
367 | return NULL; | |
368 | ||
369 | if (!just_once_each_iteration_p (loop, exit->src)) | |
370 | return NULL; | |
371 | ||
372 | return exit; | |
373 | } | |
374 | ||
375 | /* Dumps information about the induction variable IV to FILE. */ | |
376 | ||
377 | extern void dump_iv (FILE *, struct iv *); | |
378 | void | |
379 | dump_iv (FILE *file, struct iv *iv) | |
380 | { | |
e6845c23 ZD |
381 | if (iv->ssa_name) |
382 | { | |
383 | fprintf (file, "ssa name "); | |
384 | print_generic_expr (file, iv->ssa_name, TDF_SLIM); | |
385 | fprintf (file, "\n"); | |
386 | } | |
8b11a64c | 387 | |
2f4675b4 ZD |
388 | fprintf (file, " type "); |
389 | print_generic_expr (file, TREE_TYPE (iv->base), TDF_SLIM); | |
390 | fprintf (file, "\n"); | |
391 | ||
8b11a64c ZD |
392 | if (iv->step) |
393 | { | |
394 | fprintf (file, " base "); | |
395 | print_generic_expr (file, iv->base, TDF_SLIM); | |
396 | fprintf (file, "\n"); | |
397 | ||
398 | fprintf (file, " step "); | |
399 | print_generic_expr (file, iv->step, TDF_SLIM); | |
400 | fprintf (file, "\n"); | |
401 | } | |
402 | else | |
403 | { | |
404 | fprintf (file, " invariant "); | |
405 | print_generic_expr (file, iv->base, TDF_SLIM); | |
406 | fprintf (file, "\n"); | |
407 | } | |
408 | ||
e6845c23 ZD |
409 | if (iv->base_object) |
410 | { | |
411 | fprintf (file, " base object "); | |
412 | print_generic_expr (file, iv->base_object, TDF_SLIM); | |
413 | fprintf (file, "\n"); | |
414 | } | |
415 | ||
8b11a64c ZD |
416 | if (iv->biv_p) |
417 | fprintf (file, " is a biv\n"); | |
418 | } | |
419 | ||
420 | /* Dumps information about the USE to FILE. */ | |
421 | ||
422 | extern void dump_use (FILE *, struct iv_use *); | |
423 | void | |
424 | dump_use (FILE *file, struct iv_use *use) | |
425 | { | |
8b11a64c ZD |
426 | fprintf (file, "use %d\n", use->id); |
427 | ||
428 | switch (use->type) | |
429 | { | |
430 | case USE_NONLINEAR_EXPR: | |
431 | fprintf (file, " generic\n"); | |
432 | break; | |
433 | ||
434 | case USE_OUTER: | |
435 | fprintf (file, " outside\n"); | |
436 | break; | |
437 | ||
438 | case USE_ADDRESS: | |
439 | fprintf (file, " address\n"); | |
440 | break; | |
441 | ||
442 | case USE_COMPARE: | |
443 | fprintf (file, " compare\n"); | |
444 | break; | |
445 | ||
446 | default: | |
1e128c5f | 447 | gcc_unreachable (); |
8b11a64c ZD |
448 | } |
449 | ||
2f4675b4 ZD |
450 | fprintf (file, " in statement "); |
451 | print_generic_expr (file, use->stmt, TDF_SLIM); | |
452 | fprintf (file, "\n"); | |
453 | ||
454 | fprintf (file, " at position "); | |
455 | if (use->op_p) | |
456 | print_generic_expr (file, *use->op_p, TDF_SLIM); | |
457 | fprintf (file, "\n"); | |
458 | ||
e6845c23 | 459 | dump_iv (file, use->iv); |
2f4675b4 | 460 | |
eec5fec9 ZD |
461 | if (use->related_cands) |
462 | { | |
463 | fprintf (file, " related candidates "); | |
464 | dump_bitmap (file, use->related_cands); | |
465 | } | |
8b11a64c ZD |
466 | } |
467 | ||
468 | /* Dumps information about the uses to FILE. */ | |
469 | ||
470 | extern void dump_uses (FILE *, struct ivopts_data *); | |
471 | void | |
472 | dump_uses (FILE *file, struct ivopts_data *data) | |
473 | { | |
474 | unsigned i; | |
475 | struct iv_use *use; | |
476 | ||
477 | for (i = 0; i < n_iv_uses (data); i++) | |
478 | { | |
479 | use = iv_use (data, i); | |
480 | ||
481 | dump_use (file, use); | |
482 | fprintf (file, "\n"); | |
483 | } | |
484 | } | |
485 | ||
486 | /* Dumps information about induction variable candidate CAND to FILE. */ | |
487 | ||
488 | extern void dump_cand (FILE *, struct iv_cand *); | |
489 | void | |
490 | dump_cand (FILE *file, struct iv_cand *cand) | |
491 | { | |
492 | struct iv *iv = cand->iv; | |
493 | ||
494 | fprintf (file, "candidate %d%s\n", | |
495 | cand->id, cand->important ? " (important)" : ""); | |
496 | ||
9be872b7 ZD |
497 | if (cand->depends_on) |
498 | { | |
499 | fprintf (file, " depends on "); | |
500 | dump_bitmap (file, cand->depends_on); | |
501 | } | |
502 | ||
8b11a64c ZD |
503 | if (!iv) |
504 | { | |
505 | fprintf (file, " final value replacement\n"); | |
506 | return; | |
507 | } | |
508 | ||
509 | switch (cand->pos) | |
510 | { | |
511 | case IP_NORMAL: | |
512 | fprintf (file, " incremented before exit test\n"); | |
513 | break; | |
514 | ||
515 | case IP_END: | |
516 | fprintf (file, " incremented at end\n"); | |
517 | break; | |
518 | ||
519 | case IP_ORIGINAL: | |
520 | fprintf (file, " original biv\n"); | |
521 | break; | |
522 | } | |
523 | ||
e6845c23 | 524 | dump_iv (file, iv); |
8b11a64c ZD |
525 | } |
526 | ||
527 | /* Returns the info for ssa version VER. */ | |
528 | ||
529 | static inline struct version_info * | |
530 | ver_info (struct ivopts_data *data, unsigned ver) | |
531 | { | |
532 | return data->version_info + ver; | |
533 | } | |
534 | ||
535 | /* Returns the info for ssa name NAME. */ | |
536 | ||
537 | static inline struct version_info * | |
538 | name_info (struct ivopts_data *data, tree name) | |
539 | { | |
540 | return ver_info (data, SSA_NAME_VERSION (name)); | |
541 | } | |
542 | ||
543 | /* Checks whether there exists number X such that X * B = A, counting modulo | |
544 | 2^BITS. */ | |
545 | ||
546 | static bool | |
547 | divide (unsigned bits, unsigned HOST_WIDE_INT a, unsigned HOST_WIDE_INT b, | |
548 | HOST_WIDE_INT *x) | |
549 | { | |
550 | unsigned HOST_WIDE_INT mask = ~(~(unsigned HOST_WIDE_INT) 0 << (bits - 1) << 1); | |
551 | unsigned HOST_WIDE_INT inv, ex, val; | |
552 | unsigned i; | |
553 | ||
554 | a &= mask; | |
555 | b &= mask; | |
556 | ||
557 | /* First divide the whole equation by 2 as long as possible. */ | |
558 | while (!(a & 1) && !(b & 1)) | |
559 | { | |
560 | a >>= 1; | |
561 | b >>= 1; | |
562 | bits--; | |
563 | mask >>= 1; | |
564 | } | |
565 | ||
566 | if (!(b & 1)) | |
567 | { | |
568 | /* If b is still even, a is odd and there is no such x. */ | |
569 | return false; | |
570 | } | |
571 | ||
572 | /* Find the inverse of b. We compute it as | |
573 | b^(2^(bits - 1) - 1) (mod 2^bits). */ | |
574 | inv = 1; | |
575 | ex = b; | |
576 | for (i = 0; i < bits - 1; i++) | |
577 | { | |
578 | inv = (inv * ex) & mask; | |
579 | ex = (ex * ex) & mask; | |
580 | } | |
581 | ||
582 | val = (a * inv) & mask; | |
583 | ||
1e128c5f | 584 | gcc_assert (((val * b) & mask) == a); |
8b11a64c ZD |
585 | |
586 | if ((val >> (bits - 1)) & 1) | |
587 | val |= ~mask; | |
588 | ||
589 | *x = val; | |
590 | ||
591 | return true; | |
592 | } | |
593 | ||
594 | /* Returns true if STMT is after the place where the IP_NORMAL ivs will be | |
595 | emitted in LOOP. */ | |
596 | ||
597 | static bool | |
598 | stmt_after_ip_normal_pos (struct loop *loop, tree stmt) | |
599 | { | |
600 | basic_block bb = ip_normal_pos (loop), sbb = bb_for_stmt (stmt); | |
601 | ||
1e128c5f | 602 | gcc_assert (bb); |
8b11a64c ZD |
603 | |
604 | if (sbb == loop->latch) | |
605 | return true; | |
606 | ||
607 | if (sbb != bb) | |
608 | return false; | |
609 | ||
610 | return stmt == last_stmt (bb); | |
611 | } | |
612 | ||
613 | /* Returns true if STMT if after the place where the original induction | |
614 | variable CAND is incremented. */ | |
615 | ||
616 | static bool | |
617 | stmt_after_ip_original_pos (struct iv_cand *cand, tree stmt) | |
618 | { | |
619 | basic_block cand_bb = bb_for_stmt (cand->incremented_at); | |
620 | basic_block stmt_bb = bb_for_stmt (stmt); | |
621 | block_stmt_iterator bsi; | |
622 | ||
623 | if (!dominated_by_p (CDI_DOMINATORS, stmt_bb, cand_bb)) | |
624 | return false; | |
625 | ||
626 | if (stmt_bb != cand_bb) | |
627 | return true; | |
628 | ||
629 | /* Scan the block from the end, since the original ivs are usually | |
630 | incremented at the end of the loop body. */ | |
631 | for (bsi = bsi_last (stmt_bb); ; bsi_prev (&bsi)) | |
632 | { | |
633 | if (bsi_stmt (bsi) == cand->incremented_at) | |
634 | return false; | |
635 | if (bsi_stmt (bsi) == stmt) | |
636 | return true; | |
637 | } | |
638 | } | |
639 | ||
640 | /* Returns true if STMT if after the place where the induction variable | |
641 | CAND is incremented in LOOP. */ | |
642 | ||
643 | static bool | |
644 | stmt_after_increment (struct loop *loop, struct iv_cand *cand, tree stmt) | |
645 | { | |
646 | switch (cand->pos) | |
647 | { | |
648 | case IP_END: | |
649 | return false; | |
650 | ||
651 | case IP_NORMAL: | |
652 | return stmt_after_ip_normal_pos (loop, stmt); | |
653 | ||
654 | case IP_ORIGINAL: | |
655 | return stmt_after_ip_original_pos (cand, stmt); | |
656 | ||
657 | default: | |
1e128c5f | 658 | gcc_unreachable (); |
8b11a64c ZD |
659 | } |
660 | } | |
661 | ||
ca4c3169 ZD |
662 | /* Element of the table in that we cache the numbers of iterations obtained |
663 | from exits of the loop. */ | |
664 | ||
665 | struct nfe_cache_elt | |
666 | { | |
667 | /* The edge for that the number of iterations is cached. */ | |
668 | edge exit; | |
669 | ||
0388d40a | 670 | /* True if the # of iterations was successfully determined. */ |
ca4c3169 ZD |
671 | bool valid_p; |
672 | ||
673 | /* Description of # of iterations. */ | |
674 | struct tree_niter_desc niter; | |
675 | }; | |
676 | ||
677 | /* Hash function for nfe_cache_elt E. */ | |
678 | ||
679 | static hashval_t | |
680 | nfe_hash (const void *e) | |
681 | { | |
682 | const struct nfe_cache_elt *elt = e; | |
683 | ||
684 | return htab_hash_pointer (elt->exit); | |
685 | } | |
686 | ||
687 | /* Equality function for nfe_cache_elt E1 and edge E2. */ | |
688 | ||
689 | static int | |
690 | nfe_eq (const void *e1, const void *e2) | |
691 | { | |
692 | const struct nfe_cache_elt *elt1 = e1; | |
693 | ||
694 | return elt1->exit == e2; | |
695 | } | |
696 | ||
697 | /* Returns structure describing number of iterations determined from | |
698 | EXIT of DATA->current_loop, or NULL if something goes wrong. */ | |
699 | ||
700 | static struct tree_niter_desc * | |
701 | niter_for_exit (struct ivopts_data *data, edge exit) | |
702 | { | |
703 | struct nfe_cache_elt *nfe_desc; | |
704 | PTR *slot; | |
705 | ||
706 | slot = htab_find_slot_with_hash (data->niters, exit, | |
707 | htab_hash_pointer (exit), | |
708 | INSERT); | |
709 | ||
710 | if (!*slot) | |
711 | { | |
712 | nfe_desc = xmalloc (sizeof (struct nfe_cache_elt)); | |
713 | nfe_desc->exit = exit; | |
714 | nfe_desc->valid_p = number_of_iterations_exit (data->current_loop, | |
715 | exit, &nfe_desc->niter); | |
716 | *slot = nfe_desc; | |
717 | } | |
718 | else | |
719 | nfe_desc = *slot; | |
720 | ||
721 | if (!nfe_desc->valid_p) | |
722 | return NULL; | |
723 | ||
724 | return &nfe_desc->niter; | |
725 | } | |
726 | ||
727 | /* Returns structure describing number of iterations determined from | |
728 | single dominating exit of DATA->current_loop, or NULL if something | |
729 | goes wrong. */ | |
730 | ||
731 | static struct tree_niter_desc * | |
732 | niter_for_single_dom_exit (struct ivopts_data *data) | |
733 | { | |
734 | edge exit = single_dom_exit (data->current_loop); | |
735 | ||
736 | if (!exit) | |
737 | return NULL; | |
738 | ||
739 | return niter_for_exit (data, exit); | |
740 | } | |
741 | ||
8b11a64c ZD |
742 | /* Initializes data structures used by the iv optimization pass, stored |
743 | in DATA. LOOPS is the loop tree. */ | |
744 | ||
745 | static void | |
746 | tree_ssa_iv_optimize_init (struct loops *loops, struct ivopts_data *data) | |
747 | { | |
748 | unsigned i; | |
749 | ||
750 | data->version_info_size = 2 * num_ssa_names; | |
751 | data->version_info = xcalloc (data->version_info_size, | |
752 | sizeof (struct version_info)); | |
8bdbfff5 NS |
753 | data->relevant = BITMAP_ALLOC (NULL); |
754 | data->important_candidates = BITMAP_ALLOC (NULL); | |
8b11a64c | 755 | data->max_inv_id = 0; |
ca4c3169 | 756 | data->niters = htab_create (10, nfe_hash, nfe_eq, free); |
8b11a64c ZD |
757 | |
758 | for (i = 1; i < loops->num; i++) | |
759 | if (loops->parray[i]) | |
760 | loops->parray[i]->aux = xcalloc (1, sizeof (struct loop_data)); | |
761 | ||
69ebd99d KH |
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); | |
8b11a64c ZD |
765 | } |
766 | ||
e6845c23 ZD |
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); | |
774 | tree base, obj, op0, op1; | |
775 | ||
776 | if (!POINTER_TYPE_P (TREE_TYPE (expr))) | |
777 | return NULL_TREE; | |
778 | ||
779 | switch (code) | |
780 | { | |
781 | case INTEGER_CST: | |
782 | return NULL_TREE; | |
783 | ||
784 | case ADDR_EXPR: | |
785 | obj = TREE_OPERAND (expr, 0); | |
786 | base = get_base_address (obj); | |
787 | ||
788 | if (!base) | |
f5e2738c | 789 | return expr; |
e6845c23 | 790 | |
7299dbfb | 791 | if (TREE_CODE (base) == INDIRECT_REF) |
f5e2738c | 792 | return determine_base_object (TREE_OPERAND (base, 0)); |
7299dbfb | 793 | |
62b37d91 RG |
794 | return fold_convert (ptr_type_node, |
795 | build_fold_addr_expr (base)); | |
e6845c23 ZD |
796 | |
797 | case PLUS_EXPR: | |
798 | case MINUS_EXPR: | |
799 | op0 = determine_base_object (TREE_OPERAND (expr, 0)); | |
800 | op1 = determine_base_object (TREE_OPERAND (expr, 1)); | |
801 | ||
802 | if (!op1) | |
803 | return op0; | |
804 | ||
805 | if (!op0) | |
806 | return (code == PLUS_EXPR | |
807 | ? op1 | |
62b37d91 | 808 | : fold_build1 (NEGATE_EXPR, ptr_type_node, op1)); |
e6845c23 | 809 | |
62b37d91 | 810 | return fold_build2 (code, ptr_type_node, op0, op1); |
e6845c23 | 811 | |
f5e2738c ZD |
812 | case NOP_EXPR: |
813 | case CONVERT_EXPR: | |
814 | return determine_base_object (TREE_OPERAND (expr, 0)); | |
815 | ||
e6845c23 ZD |
816 | default: |
817 | return fold_convert (ptr_type_node, expr); | |
818 | } | |
819 | } | |
820 | ||
8b11a64c ZD |
821 | /* Allocates an induction variable with given initial value BASE and step STEP |
822 | for loop LOOP. */ | |
823 | ||
824 | static struct iv * | |
825 | alloc_iv (tree base, tree step) | |
826 | { | |
827 | struct iv *iv = xcalloc (1, sizeof (struct iv)); | |
828 | ||
829 | if (step && integer_zerop (step)) | |
830 | step = NULL_TREE; | |
831 | ||
832 | iv->base = base; | |
e6845c23 | 833 | iv->base_object = determine_base_object (base); |
8b11a64c ZD |
834 | iv->step = step; |
835 | iv->biv_p = false; | |
836 | iv->have_use_for = false; | |
837 | iv->use_id = 0; | |
838 | iv->ssa_name = NULL_TREE; | |
839 | ||
840 | return iv; | |
841 | } | |
842 | ||
843 | /* Sets STEP and BASE for induction variable IV. */ | |
844 | ||
845 | static void | |
846 | set_iv (struct ivopts_data *data, tree iv, tree base, tree step) | |
847 | { | |
848 | struct version_info *info = name_info (data, iv); | |
849 | ||
1e128c5f | 850 | gcc_assert (!info->iv); |
8b11a64c ZD |
851 | |
852 | bitmap_set_bit (data->relevant, SSA_NAME_VERSION (iv)); | |
853 | info->iv = alloc_iv (base, step); | |
854 | info->iv->ssa_name = iv; | |
855 | } | |
856 | ||
857 | /* Finds induction variable declaration for VAR. */ | |
858 | ||
859 | static struct iv * | |
860 | get_iv (struct ivopts_data *data, tree var) | |
861 | { | |
862 | basic_block bb; | |
863 | ||
864 | if (!name_info (data, var)->iv) | |
865 | { | |
866 | bb = bb_for_stmt (SSA_NAME_DEF_STMT (var)); | |
867 | ||
868 | if (!bb | |
869 | || !flow_bb_inside_loop_p (data->current_loop, bb)) | |
870 | set_iv (data, var, var, NULL_TREE); | |
871 | } | |
872 | ||
873 | return name_info (data, var)->iv; | |
874 | } | |
875 | ||
9be872b7 ZD |
876 | /* Determines the step of a biv defined in PHI. Returns NULL if PHI does |
877 | not define a simple affine biv with nonzero step. */ | |
8b11a64c ZD |
878 | |
879 | static tree | |
880 | determine_biv_step (tree phi) | |
881 | { | |
882 | struct loop *loop = bb_for_stmt (phi)->loop_father; | |
883 | tree name = PHI_RESULT (phi), base, step; | |
8b11a64c ZD |
884 | |
885 | if (!is_gimple_reg (name)) | |
886 | return NULL_TREE; | |
887 | ||
9be872b7 | 888 | if (!simple_iv (loop, phi, name, &base, &step, true)) |
8b11a64c ZD |
889 | return NULL_TREE; |
890 | ||
9be872b7 ZD |
891 | if (zero_p (step)) |
892 | return NULL_TREE; | |
8b11a64c ZD |
893 | |
894 | return step; | |
895 | } | |
896 | ||
be35cf60 ZD |
897 | /* Returns true if EXP is a ssa name that occurs in an abnormal phi node. */ |
898 | ||
899 | static bool | |
900 | abnormal_ssa_name_p (tree exp) | |
901 | { | |
902 | if (!exp) | |
903 | return false; | |
904 | ||
905 | if (TREE_CODE (exp) != SSA_NAME) | |
906 | return false; | |
907 | ||
908 | return SSA_NAME_OCCURS_IN_ABNORMAL_PHI (exp) != 0; | |
909 | } | |
910 | ||
911 | /* Returns false if BASE or INDEX contains a ssa name that occurs in an | |
8b11a64c ZD |
912 | abnormal phi node. Callback for for_each_index. */ |
913 | ||
914 | static bool | |
be35cf60 | 915 | idx_contains_abnormal_ssa_name_p (tree base, tree *index, |
8b11a64c ZD |
916 | void *data ATTRIBUTE_UNUSED) |
917 | { | |
be35cf60 ZD |
918 | if (TREE_CODE (base) == ARRAY_REF) |
919 | { | |
920 | if (abnormal_ssa_name_p (TREE_OPERAND (base, 2))) | |
921 | return false; | |
922 | if (abnormal_ssa_name_p (TREE_OPERAND (base, 3))) | |
923 | return false; | |
924 | } | |
8b11a64c | 925 | |
be35cf60 | 926 | return !abnormal_ssa_name_p (*index); |
8b11a64c ZD |
927 | } |
928 | ||
929 | /* Returns true if EXPR contains a ssa name that occurs in an | |
930 | abnormal phi node. */ | |
931 | ||
932 | static bool | |
933 | contains_abnormal_ssa_name_p (tree expr) | |
934 | { | |
9be872b7 ZD |
935 | enum tree_code code; |
936 | enum tree_code_class class; | |
937 | ||
938 | if (!expr) | |
939 | return false; | |
940 | ||
941 | code = TREE_CODE (expr); | |
942 | class = TREE_CODE_CLASS (code); | |
943 | ||
8b11a64c ZD |
944 | if (code == SSA_NAME) |
945 | return SSA_NAME_OCCURS_IN_ABNORMAL_PHI (expr) != 0; | |
946 | ||
947 | if (code == INTEGER_CST | |
948 | || is_gimple_min_invariant (expr)) | |
949 | return false; | |
950 | ||
951 | if (code == ADDR_EXPR) | |
6efa2c71 | 952 | return !for_each_index (&TREE_OPERAND (expr, 0), |
8b11a64c ZD |
953 | idx_contains_abnormal_ssa_name_p, |
954 | NULL); | |
955 | ||
956 | switch (class) | |
957 | { | |
6615c446 JO |
958 | case tcc_binary: |
959 | case tcc_comparison: | |
8b11a64c ZD |
960 | if (contains_abnormal_ssa_name_p (TREE_OPERAND (expr, 1))) |
961 | return true; | |
962 | ||
963 | /* Fallthru. */ | |
6615c446 | 964 | case tcc_unary: |
8b11a64c ZD |
965 | if (contains_abnormal_ssa_name_p (TREE_OPERAND (expr, 0))) |
966 | return true; | |
967 | ||
968 | break; | |
969 | ||
970 | default: | |
1e128c5f | 971 | gcc_unreachable (); |
8b11a64c ZD |
972 | } |
973 | ||
974 | return false; | |
975 | } | |
976 | ||
977 | /* Finds basic ivs. */ | |
978 | ||
979 | static bool | |
980 | find_bivs (struct ivopts_data *data) | |
981 | { | |
982 | tree phi, step, type, base; | |
983 | bool found = false; | |
984 | struct loop *loop = data->current_loop; | |
985 | ||
bb29d951 | 986 | for (phi = phi_nodes (loop->header); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
987 | { |
988 | if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (PHI_RESULT (phi))) | |
989 | continue; | |
990 | ||
991 | step = determine_biv_step (phi); | |
8b11a64c ZD |
992 | if (!step) |
993 | continue; | |
8b11a64c ZD |
994 | |
995 | base = PHI_ARG_DEF_FROM_EDGE (phi, loop_preheader_edge (loop)); | |
d7bf3bcf | 996 | base = expand_simple_operations (base); |
9be872b7 ZD |
997 | if (contains_abnormal_ssa_name_p (base) |
998 | || contains_abnormal_ssa_name_p (step)) | |
8b11a64c ZD |
999 | continue; |
1000 | ||
1001 | type = TREE_TYPE (PHI_RESULT (phi)); | |
1002 | base = fold_convert (type, base); | |
9be872b7 ZD |
1003 | if (step) |
1004 | step = fold_convert (type, step); | |
8b11a64c ZD |
1005 | |
1006 | set_iv (data, PHI_RESULT (phi), base, step); | |
1007 | found = true; | |
1008 | } | |
1009 | ||
1010 | return found; | |
1011 | } | |
1012 | ||
1013 | /* Marks basic ivs. */ | |
1014 | ||
1015 | static void | |
1016 | mark_bivs (struct ivopts_data *data) | |
1017 | { | |
1018 | tree phi, var; | |
1019 | struct iv *iv, *incr_iv; | |
1020 | struct loop *loop = data->current_loop; | |
1021 | basic_block incr_bb; | |
1022 | ||
bb29d951 | 1023 | for (phi = phi_nodes (loop->header); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
1024 | { |
1025 | iv = get_iv (data, PHI_RESULT (phi)); | |
1026 | if (!iv) | |
1027 | continue; | |
1028 | ||
1029 | var = PHI_ARG_DEF_FROM_EDGE (phi, loop_latch_edge (loop)); | |
1030 | incr_iv = get_iv (data, var); | |
1031 | if (!incr_iv) | |
1032 | continue; | |
1033 | ||
1034 | /* If the increment is in the subloop, ignore it. */ | |
1035 | incr_bb = bb_for_stmt (SSA_NAME_DEF_STMT (var)); | |
1036 | if (incr_bb->loop_father != data->current_loop | |
1037 | || (incr_bb->flags & BB_IRREDUCIBLE_LOOP)) | |
1038 | continue; | |
1039 | ||
1040 | iv->biv_p = true; | |
1041 | incr_iv->biv_p = true; | |
1042 | } | |
1043 | } | |
1044 | ||
1045 | /* Checks whether STMT defines a linear induction variable and stores its | |
1046 | parameters to BASE and STEP. */ | |
1047 | ||
1048 | static bool | |
1049 | find_givs_in_stmt_scev (struct ivopts_data *data, tree stmt, | |
1050 | tree *base, tree *step) | |
1051 | { | |
1052 | tree lhs; | |
1053 | struct loop *loop = data->current_loop; | |
1054 | ||
1055 | *base = NULL_TREE; | |
1056 | *step = NULL_TREE; | |
1057 | ||
1058 | if (TREE_CODE (stmt) != MODIFY_EXPR) | |
1059 | return false; | |
1060 | ||
1061 | lhs = TREE_OPERAND (stmt, 0); | |
1062 | if (TREE_CODE (lhs) != SSA_NAME) | |
1063 | return false; | |
1064 | ||
9be872b7 | 1065 | if (!simple_iv (loop, stmt, TREE_OPERAND (stmt, 1), base, step, true)) |
8b11a64c | 1066 | return false; |
d7bf3bcf | 1067 | *base = expand_simple_operations (*base); |
8b11a64c | 1068 | |
9be872b7 ZD |
1069 | if (contains_abnormal_ssa_name_p (*base) |
1070 | || contains_abnormal_ssa_name_p (*step)) | |
8b11a64c ZD |
1071 | return false; |
1072 | ||
1073 | return true; | |
1074 | } | |
1075 | ||
1076 | /* Finds general ivs in statement STMT. */ | |
1077 | ||
1078 | static void | |
1079 | find_givs_in_stmt (struct ivopts_data *data, tree stmt) | |
1080 | { | |
1081 | tree base, step; | |
1082 | ||
1083 | if (!find_givs_in_stmt_scev (data, stmt, &base, &step)) | |
1084 | return; | |
1085 | ||
1086 | set_iv (data, TREE_OPERAND (stmt, 0), base, step); | |
1087 | } | |
1088 | ||
1089 | /* Finds general ivs in basic block BB. */ | |
1090 | ||
1091 | static void | |
1092 | find_givs_in_bb (struct ivopts_data *data, basic_block bb) | |
1093 | { | |
1094 | block_stmt_iterator bsi; | |
1095 | ||
1096 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
1097 | find_givs_in_stmt (data, bsi_stmt (bsi)); | |
1098 | } | |
1099 | ||
1100 | /* Finds general ivs. */ | |
1101 | ||
1102 | static void | |
1103 | find_givs (struct ivopts_data *data) | |
1104 | { | |
1105 | struct loop *loop = data->current_loop; | |
1106 | basic_block *body = get_loop_body_in_dom_order (loop); | |
1107 | unsigned i; | |
1108 | ||
1109 | for (i = 0; i < loop->num_nodes; i++) | |
1110 | find_givs_in_bb (data, body[i]); | |
1111 | free (body); | |
1112 | } | |
1113 | ||
8b11a64c ZD |
1114 | /* For each ssa name defined in LOOP determines whether it is an induction |
1115 | variable and if so, its initial value and step. */ | |
1116 | ||
1117 | static bool | |
1118 | find_induction_variables (struct ivopts_data *data) | |
1119 | { | |
1120 | unsigned i; | |
87c476a2 | 1121 | bitmap_iterator bi; |
8b11a64c ZD |
1122 | |
1123 | if (!find_bivs (data)) | |
1124 | return false; | |
1125 | ||
1126 | find_givs (data); | |
1127 | mark_bivs (data); | |
8b11a64c ZD |
1128 | |
1129 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1130 | { | |
ca4c3169 ZD |
1131 | struct tree_niter_desc *niter; |
1132 | ||
1133 | niter = niter_for_single_dom_exit (data); | |
1134 | ||
1135 | if (niter) | |
8b11a64c ZD |
1136 | { |
1137 | fprintf (dump_file, " number of iterations "); | |
ca4c3169 | 1138 | print_generic_expr (dump_file, niter->niter, TDF_SLIM); |
8b11a64c ZD |
1139 | fprintf (dump_file, "\n"); |
1140 | ||
1141 | fprintf (dump_file, " may be zero if "); | |
ca4c3169 | 1142 | print_generic_expr (dump_file, niter->may_be_zero, TDF_SLIM); |
8b11a64c ZD |
1143 | fprintf (dump_file, "\n"); |
1144 | fprintf (dump_file, "\n"); | |
1145 | }; | |
1146 | ||
1147 | fprintf (dump_file, "Induction variables:\n\n"); | |
1148 | ||
87c476a2 | 1149 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
8b11a64c ZD |
1150 | { |
1151 | if (ver_info (data, i)->iv) | |
1152 | dump_iv (dump_file, ver_info (data, i)->iv); | |
87c476a2 | 1153 | } |
8b11a64c ZD |
1154 | } |
1155 | ||
1156 | return true; | |
1157 | } | |
1158 | ||
1159 | /* Records a use of type USE_TYPE at *USE_P in STMT whose value is IV. */ | |
1160 | ||
1161 | static struct iv_use * | |
1162 | record_use (struct ivopts_data *data, tree *use_p, struct iv *iv, | |
1163 | tree stmt, enum use_type use_type) | |
1164 | { | |
1165 | struct iv_use *use = xcalloc (1, sizeof (struct iv_use)); | |
1166 | ||
1167 | use->id = n_iv_uses (data); | |
1168 | use->type = use_type; | |
1169 | use->iv = iv; | |
1170 | use->stmt = stmt; | |
1171 | use->op_p = use_p; | |
8bdbfff5 | 1172 | use->related_cands = BITMAP_ALLOC (NULL); |
8b11a64c | 1173 | |
e6845c23 ZD |
1174 | /* To avoid showing ssa name in the dumps, if it was not reset by the |
1175 | caller. */ | |
1176 | iv->ssa_name = NULL_TREE; | |
1177 | ||
8b11a64c ZD |
1178 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1179 | dump_use (dump_file, use); | |
1180 | ||
69ebd99d | 1181 | VEC_safe_push (iv_use_p, heap, data->iv_uses, use); |
8b11a64c ZD |
1182 | |
1183 | return use; | |
1184 | } | |
1185 | ||
1186 | /* Checks whether OP is a loop-level invariant and if so, records it. | |
1187 | NONLINEAR_USE is true if the invariant is used in a way we do not | |
1188 | handle specially. */ | |
1189 | ||
1190 | static void | |
1191 | record_invariant (struct ivopts_data *data, tree op, bool nonlinear_use) | |
1192 | { | |
1193 | basic_block bb; | |
1194 | struct version_info *info; | |
1195 | ||
1196 | if (TREE_CODE (op) != SSA_NAME | |
1197 | || !is_gimple_reg (op)) | |
1198 | return; | |
1199 | ||
1200 | bb = bb_for_stmt (SSA_NAME_DEF_STMT (op)); | |
1201 | if (bb | |
1202 | && flow_bb_inside_loop_p (data->current_loop, bb)) | |
1203 | return; | |
1204 | ||
1205 | info = name_info (data, op); | |
1206 | info->name = op; | |
1207 | info->has_nonlin_use |= nonlinear_use; | |
1208 | if (!info->inv_id) | |
1209 | info->inv_id = ++data->max_inv_id; | |
1210 | bitmap_set_bit (data->relevant, SSA_NAME_VERSION (op)); | |
1211 | } | |
1212 | ||
1213 | /* Checks whether the use OP is interesting and if so, records it | |
1214 | as TYPE. */ | |
1215 | ||
1216 | static struct iv_use * | |
1217 | find_interesting_uses_outer_or_nonlin (struct ivopts_data *data, tree op, | |
1218 | enum use_type type) | |
1219 | { | |
1220 | struct iv *iv; | |
1221 | struct iv *civ; | |
1222 | tree stmt; | |
1223 | struct iv_use *use; | |
1224 | ||
1225 | if (TREE_CODE (op) != SSA_NAME) | |
1226 | return NULL; | |
1227 | ||
1228 | iv = get_iv (data, op); | |
1229 | if (!iv) | |
1230 | return NULL; | |
1231 | ||
1232 | if (iv->have_use_for) | |
1233 | { | |
1234 | use = iv_use (data, iv->use_id); | |
1235 | ||
1e128c5f GB |
1236 | gcc_assert (use->type == USE_NONLINEAR_EXPR |
1237 | || use->type == USE_OUTER); | |
8b11a64c ZD |
1238 | |
1239 | if (type == USE_NONLINEAR_EXPR) | |
1240 | use->type = USE_NONLINEAR_EXPR; | |
1241 | return use; | |
1242 | } | |
1243 | ||
1244 | if (zero_p (iv->step)) | |
1245 | { | |
1246 | record_invariant (data, op, true); | |
1247 | return NULL; | |
1248 | } | |
1249 | iv->have_use_for = true; | |
1250 | ||
1251 | civ = xmalloc (sizeof (struct iv)); | |
1252 | *civ = *iv; | |
1253 | ||
1254 | stmt = SSA_NAME_DEF_STMT (op); | |
1e128c5f GB |
1255 | gcc_assert (TREE_CODE (stmt) == PHI_NODE |
1256 | || TREE_CODE (stmt) == MODIFY_EXPR); | |
8b11a64c ZD |
1257 | |
1258 | use = record_use (data, NULL, civ, stmt, type); | |
1259 | iv->use_id = use->id; | |
1260 | ||
1261 | return use; | |
1262 | } | |
1263 | ||
1264 | /* Checks whether the use OP is interesting and if so, records it. */ | |
1265 | ||
1266 | static struct iv_use * | |
1267 | find_interesting_uses_op (struct ivopts_data *data, tree op) | |
1268 | { | |
1269 | return find_interesting_uses_outer_or_nonlin (data, op, USE_NONLINEAR_EXPR); | |
1270 | } | |
1271 | ||
1272 | /* Records a definition of induction variable OP that is used outside of the | |
1273 | loop. */ | |
1274 | ||
1275 | static struct iv_use * | |
1276 | find_interesting_uses_outer (struct ivopts_data *data, tree op) | |
1277 | { | |
1278 | return find_interesting_uses_outer_or_nonlin (data, op, USE_OUTER); | |
1279 | } | |
1280 | ||
1281 | /* Checks whether the condition *COND_P in STMT is interesting | |
1282 | and if so, records it. */ | |
1283 | ||
1284 | static void | |
1285 | find_interesting_uses_cond (struct ivopts_data *data, tree stmt, tree *cond_p) | |
1286 | { | |
1287 | tree *op0_p; | |
1288 | tree *op1_p; | |
1289 | struct iv *iv0 = NULL, *iv1 = NULL, *civ; | |
1290 | struct iv const_iv; | |
1291 | tree zero = integer_zero_node; | |
1292 | ||
1293 | const_iv.step = NULL_TREE; | |
1294 | ||
f5f12961 ZD |
1295 | if (TREE_CODE (*cond_p) != SSA_NAME |
1296 | && !COMPARISON_CLASS_P (*cond_p)) | |
8b11a64c ZD |
1297 | return; |
1298 | ||
1299 | if (TREE_CODE (*cond_p) == SSA_NAME) | |
1300 | { | |
1301 | op0_p = cond_p; | |
1302 | op1_p = &zero; | |
1303 | } | |
1304 | else | |
1305 | { | |
1306 | op0_p = &TREE_OPERAND (*cond_p, 0); | |
1307 | op1_p = &TREE_OPERAND (*cond_p, 1); | |
1308 | } | |
1309 | ||
1310 | if (TREE_CODE (*op0_p) == SSA_NAME) | |
1311 | iv0 = get_iv (data, *op0_p); | |
1312 | else | |
1313 | iv0 = &const_iv; | |
1314 | ||
1315 | if (TREE_CODE (*op1_p) == SSA_NAME) | |
1316 | iv1 = get_iv (data, *op1_p); | |
1317 | else | |
1318 | iv1 = &const_iv; | |
1319 | ||
1320 | if (/* When comparing with non-invariant value, we may not do any senseful | |
1321 | induction variable elimination. */ | |
1322 | (!iv0 || !iv1) | |
1323 | /* Eliminating condition based on two ivs would be nontrivial. | |
1324 | ??? TODO -- it is not really important to handle this case. */ | |
1325 | || (!zero_p (iv0->step) && !zero_p (iv1->step))) | |
1326 | { | |
1327 | find_interesting_uses_op (data, *op0_p); | |
1328 | find_interesting_uses_op (data, *op1_p); | |
1329 | return; | |
1330 | } | |
1331 | ||
1332 | if (zero_p (iv0->step) && zero_p (iv1->step)) | |
1333 | { | |
1334 | /* If both are invariants, this is a work for unswitching. */ | |
1335 | return; | |
1336 | } | |
1337 | ||
1338 | civ = xmalloc (sizeof (struct iv)); | |
1339 | *civ = zero_p (iv0->step) ? *iv1: *iv0; | |
1340 | record_use (data, cond_p, civ, stmt, USE_COMPARE); | |
1341 | } | |
1342 | ||
be35cf60 ZD |
1343 | /* Returns true if expression EXPR is obviously invariant in LOOP, |
1344 | i.e. if all its operands are defined outside of the LOOP. */ | |
1345 | ||
feb075f4 | 1346 | bool |
be35cf60 ZD |
1347 | expr_invariant_in_loop_p (struct loop *loop, tree expr) |
1348 | { | |
1349 | basic_block def_bb; | |
1350 | unsigned i, len; | |
1351 | ||
1352 | if (is_gimple_min_invariant (expr)) | |
1353 | return true; | |
1354 | ||
1355 | if (TREE_CODE (expr) == SSA_NAME) | |
1356 | { | |
1357 | def_bb = bb_for_stmt (SSA_NAME_DEF_STMT (expr)); | |
1358 | if (def_bb | |
1359 | && flow_bb_inside_loop_p (loop, def_bb)) | |
1360 | return false; | |
1361 | ||
1362 | return true; | |
1363 | } | |
1364 | ||
1365 | if (!EXPR_P (expr)) | |
1366 | return false; | |
1367 | ||
54e4aedb | 1368 | len = TREE_CODE_LENGTH (TREE_CODE (expr)); |
be35cf60 ZD |
1369 | for (i = 0; i < len; i++) |
1370 | if (!expr_invariant_in_loop_p (loop, TREE_OPERAND (expr, i))) | |
1371 | return false; | |
1372 | ||
1373 | return true; | |
1374 | } | |
1375 | ||
8b11a64c ZD |
1376 | /* Cumulates the steps of indices into DATA and replaces their values with the |
1377 | initial ones. Returns false when the value of the index cannot be determined. | |
1378 | Callback for for_each_index. */ | |
1379 | ||
1380 | struct ifs_ivopts_data | |
1381 | { | |
1382 | struct ivopts_data *ivopts_data; | |
1383 | tree stmt; | |
1384 | tree *step_p; | |
1385 | }; | |
1386 | ||
1387 | static bool | |
1388 | idx_find_step (tree base, tree *idx, void *data) | |
1389 | { | |
1390 | struct ifs_ivopts_data *dta = data; | |
1391 | struct iv *iv; | |
1c1205fb | 1392 | tree step, iv_step, lbound, off; |
2f4675b4 | 1393 | struct loop *loop = dta->ivopts_data->current_loop; |
be35cf60 ZD |
1394 | |
1395 | if (TREE_CODE (base) == MISALIGNED_INDIRECT_REF | |
1396 | || TREE_CODE (base) == ALIGN_INDIRECT_REF) | |
1397 | return false; | |
1398 | ||
1399 | /* If base is a component ref, require that the offset of the reference | |
3a7c155d | 1400 | be invariant. */ |
be35cf60 ZD |
1401 | if (TREE_CODE (base) == COMPONENT_REF) |
1402 | { | |
1403 | off = component_ref_field_offset (base); | |
1404 | return expr_invariant_in_loop_p (loop, off); | |
1405 | } | |
1406 | ||
1407 | /* If base is array, first check whether we will be able to move the | |
1408 | reference out of the loop (in order to take its address in strength | |
1409 | reduction). In order for this to work we need both lower bound | |
1410 | and step to be loop invariants. */ | |
1411 | if (TREE_CODE (base) == ARRAY_REF) | |
1412 | { | |
1413 | step = array_ref_element_size (base); | |
1414 | lbound = array_ref_low_bound (base); | |
1415 | ||
1416 | if (!expr_invariant_in_loop_p (loop, step) | |
1417 | || !expr_invariant_in_loop_p (loop, lbound)) | |
1418 | return false; | |
1419 | } | |
1420 | ||
8b11a64c ZD |
1421 | if (TREE_CODE (*idx) != SSA_NAME) |
1422 | return true; | |
1423 | ||
1424 | iv = get_iv (dta->ivopts_data, *idx); | |
1425 | if (!iv) | |
1426 | return false; | |
1427 | ||
1428 | *idx = iv->base; | |
1429 | ||
1430 | if (!iv->step) | |
1431 | return true; | |
1432 | ||
8b11a64c | 1433 | if (TREE_CODE (base) == ARRAY_REF) |
2f4675b4 ZD |
1434 | { |
1435 | step = array_ref_element_size (base); | |
2f4675b4 ZD |
1436 | |
1437 | /* We only handle addresses whose step is an integer constant. */ | |
1438 | if (TREE_CODE (step) != INTEGER_CST) | |
1439 | return false; | |
2f4675b4 | 1440 | } |
8b11a64c | 1441 | else |
5212068f | 1442 | /* The step for pointer arithmetics already is 1 byte. */ |
1c1205fb | 1443 | step = build_int_cst (sizetype, 1); |
8b11a64c | 1444 | |
1c1205fb | 1445 | if (TYPE_PRECISION (TREE_TYPE (iv->base)) < TYPE_PRECISION (sizetype)) |
8b11a64c | 1446 | iv_step = can_count_iv_in_wider_type (dta->ivopts_data->current_loop, |
1c1205fb | 1447 | sizetype, iv->base, iv->step, dta->stmt); |
8b11a64c | 1448 | else |
1c1205fb | 1449 | iv_step = fold_convert (sizetype, iv->step); |
8b11a64c ZD |
1450 | |
1451 | if (!iv_step) | |
1452 | { | |
1453 | /* The index might wrap. */ | |
1454 | return false; | |
1455 | } | |
1456 | ||
1c1205fb | 1457 | step = fold_build2 (MULT_EXPR, sizetype, step, iv_step); |
8b11a64c ZD |
1458 | |
1459 | if (!*dta->step_p) | |
1460 | *dta->step_p = step; | |
1461 | else | |
1c1205fb | 1462 | *dta->step_p = fold_build2 (PLUS_EXPR, sizetype, *dta->step_p, step); |
8b11a64c ZD |
1463 | |
1464 | return true; | |
1465 | } | |
1466 | ||
1467 | /* Records use in index IDX. Callback for for_each_index. Ivopts data | |
1468 | object is passed to it in DATA. */ | |
1469 | ||
1470 | static bool | |
2f4675b4 | 1471 | idx_record_use (tree base, tree *idx, |
8b11a64c ZD |
1472 | void *data) |
1473 | { | |
1474 | find_interesting_uses_op (data, *idx); | |
2f4675b4 ZD |
1475 | if (TREE_CODE (base) == ARRAY_REF) |
1476 | { | |
1477 | find_interesting_uses_op (data, array_ref_element_size (base)); | |
1478 | find_interesting_uses_op (data, array_ref_low_bound (base)); | |
1479 | } | |
8b11a64c ZD |
1480 | return true; |
1481 | } | |
1482 | ||
0a915e3d ZD |
1483 | /* Returns true if memory reference REF may be unaligned. */ |
1484 | ||
1485 | static bool | |
1486 | may_be_unaligned_p (tree ref) | |
1487 | { | |
1488 | tree base; | |
1489 | tree base_type; | |
1490 | HOST_WIDE_INT bitsize; | |
1491 | HOST_WIDE_INT bitpos; | |
1492 | tree toffset; | |
1493 | enum machine_mode mode; | |
1494 | int unsignedp, volatilep; | |
1495 | unsigned base_align; | |
1496 | ||
1497 | /* The test below is basically copy of what expr.c:normal_inner_ref | |
1498 | does to check whether the object must be loaded by parts when | |
1499 | STRICT_ALIGNMENT is true. */ | |
1500 | base = get_inner_reference (ref, &bitsize, &bitpos, &toffset, &mode, | |
1501 | &unsignedp, &volatilep, true); | |
1502 | base_type = TREE_TYPE (base); | |
1503 | base_align = TYPE_ALIGN (base_type); | |
1504 | ||
1505 | if (mode != BLKmode | |
1506 | && (base_align < GET_MODE_ALIGNMENT (mode) | |
1507 | || bitpos % GET_MODE_ALIGNMENT (mode) != 0 | |
1508 | || bitpos % BITS_PER_UNIT != 0)) | |
1509 | return true; | |
1510 | ||
1511 | return false; | |
1512 | } | |
1513 | ||
8b11a64c ZD |
1514 | /* Finds addresses in *OP_P inside STMT. */ |
1515 | ||
1516 | static void | |
1517 | find_interesting_uses_address (struct ivopts_data *data, tree stmt, tree *op_p) | |
1518 | { | |
1519 | tree base = unshare_expr (*op_p), step = NULL; | |
1520 | struct iv *civ; | |
1521 | struct ifs_ivopts_data ifs_ivopts_data; | |
1522 | ||
e3cc7254 ZD |
1523 | /* Do not play with volatile memory references. A bit too conservative, |
1524 | perhaps, but safe. */ | |
1525 | if (stmt_ann (stmt)->has_volatile_ops) | |
1526 | goto fail; | |
1527 | ||
8b11a64c ZD |
1528 | /* Ignore bitfields for now. Not really something terribly complicated |
1529 | to handle. TODO. */ | |
1530 | if (TREE_CODE (base) == COMPONENT_REF | |
1531 | && DECL_NONADDRESSABLE_P (TREE_OPERAND (base, 1))) | |
1532 | goto fail; | |
1533 | ||
0a915e3d ZD |
1534 | if (STRICT_ALIGNMENT |
1535 | && may_be_unaligned_p (base)) | |
1536 | goto fail; | |
1537 | ||
8b11a64c ZD |
1538 | ifs_ivopts_data.ivopts_data = data; |
1539 | ifs_ivopts_data.stmt = stmt; | |
1540 | ifs_ivopts_data.step_p = &step; | |
1541 | if (!for_each_index (&base, idx_find_step, &ifs_ivopts_data) | |
1542 | || zero_p (step)) | |
1543 | goto fail; | |
1544 | ||
be35cf60 ZD |
1545 | gcc_assert (TREE_CODE (base) != ALIGN_INDIRECT_REF); |
1546 | gcc_assert (TREE_CODE (base) != MISALIGNED_INDIRECT_REF); | |
1547 | ||
d5dc1717 | 1548 | base = build_fold_addr_expr (base); |
8b11a64c ZD |
1549 | |
1550 | civ = alloc_iv (base, step); | |
1551 | record_use (data, op_p, civ, stmt, USE_ADDRESS); | |
1552 | return; | |
1553 | ||
1554 | fail: | |
1555 | for_each_index (op_p, idx_record_use, data); | |
1556 | } | |
1557 | ||
1558 | /* Finds and records invariants used in STMT. */ | |
1559 | ||
1560 | static void | |
1561 | find_invariants_stmt (struct ivopts_data *data, tree stmt) | |
1562 | { | |
f47c96aa AM |
1563 | ssa_op_iter iter; |
1564 | use_operand_p use_p; | |
8b11a64c ZD |
1565 | tree op; |
1566 | ||
f47c96aa | 1567 | FOR_EACH_PHI_OR_STMT_USE (use_p, stmt, iter, SSA_OP_USE) |
8b11a64c | 1568 | { |
f47c96aa | 1569 | op = USE_FROM_PTR (use_p); |
8b11a64c ZD |
1570 | record_invariant (data, op, false); |
1571 | } | |
1572 | } | |
1573 | ||
1574 | /* Finds interesting uses of induction variables in the statement STMT. */ | |
1575 | ||
1576 | static void | |
1577 | find_interesting_uses_stmt (struct ivopts_data *data, tree stmt) | |
1578 | { | |
1579 | struct iv *iv; | |
1580 | tree op, lhs, rhs; | |
f47c96aa AM |
1581 | ssa_op_iter iter; |
1582 | use_operand_p use_p; | |
8b11a64c ZD |
1583 | |
1584 | find_invariants_stmt (data, stmt); | |
1585 | ||
1586 | if (TREE_CODE (stmt) == COND_EXPR) | |
1587 | { | |
1588 | find_interesting_uses_cond (data, stmt, &COND_EXPR_COND (stmt)); | |
1589 | return; | |
1590 | } | |
1591 | ||
1592 | if (TREE_CODE (stmt) == MODIFY_EXPR) | |
1593 | { | |
1594 | lhs = TREE_OPERAND (stmt, 0); | |
1595 | rhs = TREE_OPERAND (stmt, 1); | |
1596 | ||
1597 | if (TREE_CODE (lhs) == SSA_NAME) | |
1598 | { | |
1599 | /* If the statement defines an induction variable, the uses are not | |
1600 | interesting by themselves. */ | |
1601 | ||
1602 | iv = get_iv (data, lhs); | |
1603 | ||
1604 | if (iv && !zero_p (iv->step)) | |
1605 | return; | |
1606 | } | |
1607 | ||
1608 | switch (TREE_CODE_CLASS (TREE_CODE (rhs))) | |
1609 | { | |
6615c446 | 1610 | case tcc_comparison: |
8b11a64c ZD |
1611 | find_interesting_uses_cond (data, stmt, &TREE_OPERAND (stmt, 1)); |
1612 | return; | |
1613 | ||
6615c446 | 1614 | case tcc_reference: |
8b11a64c | 1615 | find_interesting_uses_address (data, stmt, &TREE_OPERAND (stmt, 1)); |
6615c446 | 1616 | if (REFERENCE_CLASS_P (lhs)) |
8b11a64c ZD |
1617 | find_interesting_uses_address (data, stmt, &TREE_OPERAND (stmt, 0)); |
1618 | return; | |
1619 | ||
1620 | default: ; | |
1621 | } | |
1622 | ||
6615c446 | 1623 | if (REFERENCE_CLASS_P (lhs) |
2f4675b4 | 1624 | && is_gimple_val (rhs)) |
8b11a64c ZD |
1625 | { |
1626 | find_interesting_uses_address (data, stmt, &TREE_OPERAND (stmt, 0)); | |
1627 | find_interesting_uses_op (data, rhs); | |
1628 | return; | |
1629 | } | |
2f4675b4 ZD |
1630 | |
1631 | /* TODO -- we should also handle address uses of type | |
1632 | ||
1633 | memory = call (whatever); | |
1634 | ||
1635 | and | |
1636 | ||
1637 | call (memory). */ | |
8b11a64c ZD |
1638 | } |
1639 | ||
1640 | if (TREE_CODE (stmt) == PHI_NODE | |
1641 | && bb_for_stmt (stmt) == data->current_loop->header) | |
1642 | { | |
1643 | lhs = PHI_RESULT (stmt); | |
1644 | iv = get_iv (data, lhs); | |
1645 | ||
1646 | if (iv && !zero_p (iv->step)) | |
1647 | return; | |
1648 | } | |
1649 | ||
f47c96aa | 1650 | FOR_EACH_PHI_OR_STMT_USE (use_p, stmt, iter, SSA_OP_USE) |
8b11a64c | 1651 | { |
f47c96aa | 1652 | op = USE_FROM_PTR (use_p); |
8b11a64c ZD |
1653 | |
1654 | if (TREE_CODE (op) != SSA_NAME) | |
1655 | continue; | |
1656 | ||
1657 | iv = get_iv (data, op); | |
1658 | if (!iv) | |
1659 | continue; | |
1660 | ||
1661 | find_interesting_uses_op (data, op); | |
1662 | } | |
1663 | } | |
1664 | ||
1665 | /* Finds interesting uses of induction variables outside of loops | |
1666 | on loop exit edge EXIT. */ | |
1667 | ||
1668 | static void | |
1669 | find_interesting_uses_outside (struct ivopts_data *data, edge exit) | |
1670 | { | |
1671 | tree phi, def; | |
1672 | ||
bb29d951 | 1673 | for (phi = phi_nodes (exit->dest); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
1674 | { |
1675 | def = PHI_ARG_DEF_FROM_EDGE (phi, exit); | |
1676 | find_interesting_uses_outer (data, def); | |
1677 | } | |
1678 | } | |
1679 | ||
1680 | /* Finds uses of the induction variables that are interesting. */ | |
1681 | ||
1682 | static void | |
1683 | find_interesting_uses (struct ivopts_data *data) | |
1684 | { | |
1685 | basic_block bb; | |
1686 | block_stmt_iterator bsi; | |
1687 | tree phi; | |
1688 | basic_block *body = get_loop_body (data->current_loop); | |
1689 | unsigned i; | |
1690 | struct version_info *info; | |
1691 | edge e; | |
1692 | ||
1693 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1694 | fprintf (dump_file, "Uses:\n\n"); | |
1695 | ||
1696 | for (i = 0; i < data->current_loop->num_nodes; i++) | |
1697 | { | |
628f6a4e | 1698 | edge_iterator ei; |
8b11a64c ZD |
1699 | bb = body[i]; |
1700 | ||
628f6a4e | 1701 | FOR_EACH_EDGE (e, ei, bb->succs) |
8b11a64c ZD |
1702 | if (e->dest != EXIT_BLOCK_PTR |
1703 | && !flow_bb_inside_loop_p (data->current_loop, e->dest)) | |
1704 | find_interesting_uses_outside (data, e); | |
1705 | ||
bb29d951 | 1706 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
1707 | find_interesting_uses_stmt (data, phi); |
1708 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
1709 | find_interesting_uses_stmt (data, bsi_stmt (bsi)); | |
1710 | } | |
1711 | ||
1712 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1713 | { | |
87c476a2 ZD |
1714 | bitmap_iterator bi; |
1715 | ||
8b11a64c ZD |
1716 | fprintf (dump_file, "\n"); |
1717 | ||
87c476a2 | 1718 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
8b11a64c ZD |
1719 | { |
1720 | info = ver_info (data, i); | |
1721 | if (info->inv_id) | |
1722 | { | |
1723 | fprintf (dump_file, " "); | |
1724 | print_generic_expr (dump_file, info->name, TDF_SLIM); | |
1725 | fprintf (dump_file, " is invariant (%d)%s\n", | |
1726 | info->inv_id, info->has_nonlin_use ? "" : ", eliminable"); | |
1727 | } | |
87c476a2 | 1728 | } |
8b11a64c ZD |
1729 | |
1730 | fprintf (dump_file, "\n"); | |
1731 | } | |
1732 | ||
1733 | free (body); | |
1734 | } | |
1735 | ||
f5e2738c | 1736 | /* Strips constant offsets from EXPR and stores them to OFFSET. If INSIDE_ADDR |
9be872b7 ZD |
1737 | is true, assume we are inside an address. If TOP_COMPREF is true, assume |
1738 | we are at the top-level of the processed address. */ | |
f5e2738c ZD |
1739 | |
1740 | static tree | |
9be872b7 ZD |
1741 | strip_offset_1 (tree expr, bool inside_addr, bool top_compref, |
1742 | unsigned HOST_WIDE_INT *offset) | |
f5e2738c | 1743 | { |
9be872b7 | 1744 | tree op0 = NULL_TREE, op1 = NULL_TREE, tmp, step; |
f5e2738c ZD |
1745 | enum tree_code code; |
1746 | tree type, orig_type = TREE_TYPE (expr); | |
1747 | unsigned HOST_WIDE_INT off0, off1, st; | |
1748 | tree orig_expr = expr; | |
1749 | ||
1750 | STRIP_NOPS (expr); | |
9be872b7 | 1751 | |
f5e2738c ZD |
1752 | type = TREE_TYPE (expr); |
1753 | code = TREE_CODE (expr); | |
1754 | *offset = 0; | |
1755 | ||
1756 | switch (code) | |
1757 | { | |
1758 | case INTEGER_CST: | |
1759 | if (!cst_and_fits_in_hwi (expr) | |
1760 | || zero_p (expr)) | |
1761 | return orig_expr; | |
1762 | ||
1763 | *offset = int_cst_value (expr); | |
1764 | return build_int_cst_type (orig_type, 0); | |
1765 | ||
1766 | case PLUS_EXPR: | |
1767 | case MINUS_EXPR: | |
1768 | op0 = TREE_OPERAND (expr, 0); | |
1769 | op1 = TREE_OPERAND (expr, 1); | |
1770 | ||
9be872b7 ZD |
1771 | op0 = strip_offset_1 (op0, false, false, &off0); |
1772 | op1 = strip_offset_1 (op1, false, false, &off1); | |
f5e2738c ZD |
1773 | |
1774 | *offset = (code == PLUS_EXPR ? off0 + off1 : off0 - off1); | |
1775 | if (op0 == TREE_OPERAND (expr, 0) | |
1776 | && op1 == TREE_OPERAND (expr, 1)) | |
1777 | return orig_expr; | |
1778 | ||
1779 | if (zero_p (op1)) | |
1780 | expr = op0; | |
1781 | else if (zero_p (op0)) | |
1782 | { | |
1783 | if (code == PLUS_EXPR) | |
1784 | expr = op1; | |
1785 | else | |
9be872b7 | 1786 | expr = fold_build1 (NEGATE_EXPR, type, op1); |
f5e2738c ZD |
1787 | } |
1788 | else | |
9be872b7 | 1789 | expr = fold_build2 (code, type, op0, op1); |
f5e2738c ZD |
1790 | |
1791 | return fold_convert (orig_type, expr); | |
1792 | ||
1793 | case ARRAY_REF: | |
1794 | if (!inside_addr) | |
1795 | return orig_expr; | |
1796 | ||
1797 | step = array_ref_element_size (expr); | |
1798 | if (!cst_and_fits_in_hwi (step)) | |
1799 | break; | |
1800 | ||
1801 | st = int_cst_value (step); | |
1802 | op1 = TREE_OPERAND (expr, 1); | |
9be872b7 | 1803 | op1 = strip_offset_1 (op1, false, false, &off1); |
f5e2738c | 1804 | *offset = off1 * st; |
9be872b7 ZD |
1805 | |
1806 | if (top_compref | |
1807 | && zero_p (op1)) | |
1808 | { | |
1809 | /* Strip the component reference completely. */ | |
1810 | op0 = TREE_OPERAND (expr, 0); | |
1811 | op0 = strip_offset_1 (op0, inside_addr, top_compref, &off0); | |
1812 | *offset += off0; | |
1813 | return op0; | |
1814 | } | |
f5e2738c ZD |
1815 | break; |
1816 | ||
1817 | case COMPONENT_REF: | |
1818 | if (!inside_addr) | |
1819 | return orig_expr; | |
9be872b7 ZD |
1820 | |
1821 | tmp = component_ref_field_offset (expr); | |
1822 | if (top_compref | |
1823 | && cst_and_fits_in_hwi (tmp)) | |
1824 | { | |
1825 | /* Strip the component reference completely. */ | |
1826 | op0 = TREE_OPERAND (expr, 0); | |
1827 | op0 = strip_offset_1 (op0, inside_addr, top_compref, &off0); | |
1828 | *offset = off0 + int_cst_value (tmp); | |
1829 | return op0; | |
1830 | } | |
f5e2738c ZD |
1831 | break; |
1832 | ||
1833 | case ADDR_EXPR: | |
9be872b7 ZD |
1834 | op0 = TREE_OPERAND (expr, 0); |
1835 | op0 = strip_offset_1 (op0, true, true, &off0); | |
1836 | *offset += off0; | |
1837 | ||
1838 | if (op0 == TREE_OPERAND (expr, 0)) | |
1839 | return orig_expr; | |
1840 | ||
d5dc1717 | 1841 | expr = build_fold_addr_expr (op0); |
9be872b7 ZD |
1842 | return fold_convert (orig_type, expr); |
1843 | ||
1844 | case INDIRECT_REF: | |
1845 | inside_addr = false; | |
f5e2738c ZD |
1846 | break; |
1847 | ||
1848 | default: | |
1849 | return orig_expr; | |
1850 | } | |
1851 | ||
1852 | /* Default handling of expressions for that we want to recurse into | |
1853 | the first operand. */ | |
1854 | op0 = TREE_OPERAND (expr, 0); | |
9be872b7 | 1855 | op0 = strip_offset_1 (op0, inside_addr, false, &off0); |
f5e2738c ZD |
1856 | *offset += off0; |
1857 | ||
1858 | if (op0 == TREE_OPERAND (expr, 0) | |
1859 | && (!op1 || op1 == TREE_OPERAND (expr, 1))) | |
1860 | return orig_expr; | |
1861 | ||
1862 | expr = copy_node (expr); | |
1863 | TREE_OPERAND (expr, 0) = op0; | |
1864 | if (op1) | |
1865 | TREE_OPERAND (expr, 1) = op1; | |
1866 | ||
9be872b7 | 1867 | /* Inside address, we might strip the top level component references, |
0fa2e4df | 1868 | thus changing type of the expression. Handling of ADDR_EXPR |
9be872b7 ZD |
1869 | will fix that. */ |
1870 | expr = fold_convert (orig_type, expr); | |
1871 | ||
1872 | return expr; | |
1873 | } | |
1874 | ||
1875 | /* Strips constant offsets from EXPR and stores them to OFFSET. */ | |
1876 | ||
1877 | static tree | |
1878 | strip_offset (tree expr, unsigned HOST_WIDE_INT *offset) | |
1879 | { | |
1880 | return strip_offset_1 (expr, false, false, offset); | |
f5e2738c ZD |
1881 | } |
1882 | ||
d482f417 ZD |
1883 | /* Returns variant of TYPE that can be used as base for different uses. |
1884 | For integer types, we return unsigned variant of the type, which | |
1885 | avoids problems with overflows. For pointer types, we return void *. */ | |
1886 | ||
1887 | static tree | |
1888 | generic_type_for (tree type) | |
1889 | { | |
1890 | if (POINTER_TYPE_P (type)) | |
1891 | return ptr_type_node; | |
1892 | ||
1893 | if (TYPE_UNSIGNED (type)) | |
1894 | return type; | |
1895 | ||
1896 | return unsigned_type_for (type); | |
1897 | } | |
1898 | ||
9be872b7 ZD |
1899 | /* Records invariants in *EXPR_P. Callback for walk_tree. DATA contains |
1900 | the bitmap to that we should store it. */ | |
1901 | ||
1902 | static struct ivopts_data *fd_ivopts_data; | |
1903 | static tree | |
1904 | find_depends (tree *expr_p, int *ws ATTRIBUTE_UNUSED, void *data) | |
1905 | { | |
1906 | bitmap *depends_on = data; | |
1907 | struct version_info *info; | |
1908 | ||
1909 | if (TREE_CODE (*expr_p) != SSA_NAME) | |
1910 | return NULL_TREE; | |
1911 | info = name_info (fd_ivopts_data, *expr_p); | |
1912 | ||
1913 | if (!info->inv_id || info->has_nonlin_use) | |
1914 | return NULL_TREE; | |
1915 | ||
1916 | if (!*depends_on) | |
1917 | *depends_on = BITMAP_ALLOC (NULL); | |
1918 | bitmap_set_bit (*depends_on, info->inv_id); | |
1919 | ||
1920 | return NULL_TREE; | |
1921 | } | |
1922 | ||
8b11a64c ZD |
1923 | /* Adds a candidate BASE + STEP * i. Important field is set to IMPORTANT and |
1924 | position to POS. If USE is not NULL, the candidate is set as related to | |
1925 | it. If both BASE and STEP are NULL, we add a pseudocandidate for the | |
1926 | replacement of the final value of the iv by a direct computation. */ | |
1927 | ||
1928 | static struct iv_cand * | |
1929 | add_candidate_1 (struct ivopts_data *data, | |
1930 | tree base, tree step, bool important, enum iv_position pos, | |
1931 | struct iv_use *use, tree incremented_at) | |
1932 | { | |
1933 | unsigned i; | |
1934 | struct iv_cand *cand = NULL; | |
d482f417 | 1935 | tree type, orig_type; |
8b11a64c ZD |
1936 | |
1937 | if (base) | |
1938 | { | |
d482f417 ZD |
1939 | orig_type = TREE_TYPE (base); |
1940 | type = generic_type_for (orig_type); | |
1941 | if (type != orig_type) | |
8b11a64c | 1942 | { |
8b11a64c ZD |
1943 | base = fold_convert (type, base); |
1944 | if (step) | |
1945 | step = fold_convert (type, step); | |
1946 | } | |
1947 | } | |
1948 | ||
1949 | for (i = 0; i < n_iv_cands (data); i++) | |
1950 | { | |
1951 | cand = iv_cand (data, i); | |
1952 | ||
1953 | if (cand->pos != pos) | |
1954 | continue; | |
1955 | ||
1956 | if (cand->incremented_at != incremented_at) | |
1957 | continue; | |
1958 | ||
1959 | if (!cand->iv) | |
1960 | { | |
1961 | if (!base && !step) | |
1962 | break; | |
1963 | ||
1964 | continue; | |
1965 | } | |
1966 | ||
1967 | if (!base && !step) | |
1968 | continue; | |
1969 | ||
1970 | if (!operand_equal_p (base, cand->iv->base, 0)) | |
1971 | continue; | |
1972 | ||
1973 | if (zero_p (cand->iv->step)) | |
1974 | { | |
1975 | if (zero_p (step)) | |
1976 | break; | |
1977 | } | |
1978 | else | |
1979 | { | |
1980 | if (step && operand_equal_p (step, cand->iv->step, 0)) | |
1981 | break; | |
1982 | } | |
1983 | } | |
1984 | ||
1985 | if (i == n_iv_cands (data)) | |
1986 | { | |
1987 | cand = xcalloc (1, sizeof (struct iv_cand)); | |
1988 | cand->id = i; | |
1989 | ||
1990 | if (!base && !step) | |
1991 | cand->iv = NULL; | |
1992 | else | |
1993 | cand->iv = alloc_iv (base, step); | |
1994 | ||
1995 | cand->pos = pos; | |
1996 | if (pos != IP_ORIGINAL && cand->iv) | |
1997 | { | |
1998 | cand->var_before = create_tmp_var_raw (TREE_TYPE (base), "ivtmp"); | |
1999 | cand->var_after = cand->var_before; | |
2000 | } | |
2001 | cand->important = important; | |
2002 | cand->incremented_at = incremented_at; | |
69ebd99d | 2003 | VEC_safe_push (iv_cand_p, heap, data->iv_candidates, cand); |
8b11a64c | 2004 | |
9be872b7 ZD |
2005 | if (step |
2006 | && TREE_CODE (step) != INTEGER_CST) | |
2007 | { | |
2008 | fd_ivopts_data = data; | |
2009 | walk_tree (&step, find_depends, &cand->depends_on, NULL); | |
2010 | } | |
2011 | ||
8b11a64c ZD |
2012 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2013 | dump_cand (dump_file, cand); | |
2014 | } | |
2015 | ||
2016 | if (important && !cand->important) | |
2017 | { | |
2018 | cand->important = true; | |
2019 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2020 | fprintf (dump_file, "Candidate %d is important\n", cand->id); | |
2021 | } | |
2022 | ||
2023 | if (use) | |
2024 | { | |
2025 | bitmap_set_bit (use->related_cands, i); | |
2026 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2027 | fprintf (dump_file, "Candidate %d is related to use %d\n", | |
2028 | cand->id, use->id); | |
2029 | } | |
2030 | ||
2031 | return cand; | |
2032 | } | |
2033 | ||
4366cf6d ZD |
2034 | /* Returns true if incrementing the induction variable at the end of the LOOP |
2035 | is allowed. | |
2036 | ||
2037 | The purpose is to avoid splitting latch edge with a biv increment, thus | |
2038 | creating a jump, possibly confusing other optimization passes and leaving | |
2039 | less freedom to scheduler. So we allow IP_END_POS only if IP_NORMAL_POS | |
2040 | is not available (so we do not have a better alternative), or if the latch | |
2041 | edge is already nonempty. */ | |
2042 | ||
2043 | static bool | |
2044 | allow_ip_end_pos_p (struct loop *loop) | |
2045 | { | |
2046 | if (!ip_normal_pos (loop)) | |
2047 | return true; | |
2048 | ||
2049 | if (!empty_block_p (ip_end_pos (loop))) | |
2050 | return true; | |
2051 | ||
2052 | return false; | |
2053 | } | |
2054 | ||
8b11a64c ZD |
2055 | /* Adds a candidate BASE + STEP * i. Important field is set to IMPORTANT and |
2056 | position to POS. If USE is not NULL, the candidate is set as related to | |
2057 | it. The candidate computation is scheduled on all available positions. */ | |
2058 | ||
2059 | static void | |
2060 | add_candidate (struct ivopts_data *data, | |
2061 | tree base, tree step, bool important, struct iv_use *use) | |
2062 | { | |
2063 | if (ip_normal_pos (data->current_loop)) | |
2064 | add_candidate_1 (data, base, step, important, IP_NORMAL, use, NULL_TREE); | |
4366cf6d ZD |
2065 | if (ip_end_pos (data->current_loop) |
2066 | && allow_ip_end_pos_p (data->current_loop)) | |
8b11a64c ZD |
2067 | add_candidate_1 (data, base, step, important, IP_END, use, NULL_TREE); |
2068 | } | |
2069 | ||
39b4020c RS |
2070 | /* Add a standard "0 + 1 * iteration" iv candidate for a |
2071 | type with SIZE bits. */ | |
2072 | ||
2073 | static void | |
2074 | add_standard_iv_candidates_for_size (struct ivopts_data *data, | |
2075 | unsigned int size) | |
2076 | { | |
2077 | tree type = lang_hooks.types.type_for_size (size, true); | |
2078 | add_candidate (data, build_int_cst (type, 0), build_int_cst (type, 1), | |
2079 | true, NULL); | |
2080 | } | |
2081 | ||
8b11a64c ZD |
2082 | /* Adds standard iv candidates. */ |
2083 | ||
2084 | static void | |
2085 | add_standard_iv_candidates (struct ivopts_data *data) | |
2086 | { | |
39b4020c | 2087 | add_standard_iv_candidates_for_size (data, INT_TYPE_SIZE); |
8b11a64c | 2088 | |
39b4020c RS |
2089 | /* The same for a double-integer type if it is still fast enough. */ |
2090 | if (BITS_PER_WORD >= INT_TYPE_SIZE * 2) | |
2091 | add_standard_iv_candidates_for_size (data, INT_TYPE_SIZE * 2); | |
8b11a64c ZD |
2092 | } |
2093 | ||
2094 | ||
2095 | /* Adds candidates bases on the old induction variable IV. */ | |
2096 | ||
2097 | static void | |
2098 | add_old_iv_candidates (struct ivopts_data *data, struct iv *iv) | |
2099 | { | |
2100 | tree phi, def; | |
2101 | struct iv_cand *cand; | |
2102 | ||
2103 | add_candidate (data, iv->base, iv->step, true, NULL); | |
2104 | ||
2105 | /* The same, but with initial value zero. */ | |
2106 | add_candidate (data, | |
5212068f | 2107 | build_int_cst (TREE_TYPE (iv->base), 0), |
8b11a64c ZD |
2108 | iv->step, true, NULL); |
2109 | ||
2110 | phi = SSA_NAME_DEF_STMT (iv->ssa_name); | |
2111 | if (TREE_CODE (phi) == PHI_NODE) | |
2112 | { | |
2113 | /* Additionally record the possibility of leaving the original iv | |
2114 | untouched. */ | |
2115 | def = PHI_ARG_DEF_FROM_EDGE (phi, loop_latch_edge (data->current_loop)); | |
2116 | cand = add_candidate_1 (data, | |
2117 | iv->base, iv->step, true, IP_ORIGINAL, NULL, | |
2118 | SSA_NAME_DEF_STMT (def)); | |
2119 | cand->var_before = iv->ssa_name; | |
2120 | cand->var_after = def; | |
2121 | } | |
2122 | } | |
2123 | ||
2124 | /* Adds candidates based on the old induction variables. */ | |
2125 | ||
2126 | static void | |
2127 | add_old_ivs_candidates (struct ivopts_data *data) | |
2128 | { | |
2129 | unsigned i; | |
2130 | struct iv *iv; | |
87c476a2 | 2131 | bitmap_iterator bi; |
8b11a64c | 2132 | |
87c476a2 | 2133 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
8b11a64c ZD |
2134 | { |
2135 | iv = ver_info (data, i)->iv; | |
2136 | if (iv && iv->biv_p && !zero_p (iv->step)) | |
2137 | add_old_iv_candidates (data, iv); | |
87c476a2 | 2138 | } |
8b11a64c ZD |
2139 | } |
2140 | ||
2141 | /* Adds candidates based on the value of the induction variable IV and USE. */ | |
2142 | ||
2143 | static void | |
2144 | add_iv_value_candidates (struct ivopts_data *data, | |
2145 | struct iv *iv, struct iv_use *use) | |
2146 | { | |
f5e2738c | 2147 | unsigned HOST_WIDE_INT offset; |
9be872b7 | 2148 | tree base; |
8b11a64c | 2149 | |
9be872b7 | 2150 | add_candidate (data, iv->base, iv->step, false, use); |
be35cf60 | 2151 | |
9be872b7 ZD |
2152 | /* The same, but with initial value zero. Make such variable important, |
2153 | since it is generic enough so that possibly many uses may be based | |
2154 | on it. */ | |
2155 | add_candidate (data, build_int_cst (TREE_TYPE (iv->base), 0), | |
2156 | iv->step, true, use); | |
8b11a64c ZD |
2157 | |
2158 | /* Third, try removing the constant offset. */ | |
9be872b7 | 2159 | base = strip_offset (iv->base, &offset); |
f5e2738c ZD |
2160 | if (offset) |
2161 | add_candidate (data, base, iv->step, false, use); | |
8b11a64c ZD |
2162 | } |
2163 | ||
2164 | /* Possibly adds pseudocandidate for replacing the final value of USE by | |
2165 | a direct computation. */ | |
2166 | ||
2167 | static void | |
2168 | add_iv_outer_candidates (struct ivopts_data *data, struct iv_use *use) | |
2169 | { | |
2170 | struct tree_niter_desc *niter; | |
8b11a64c ZD |
2171 | |
2172 | /* We must know where we exit the loop and how many times does it roll. */ | |
ca4c3169 ZD |
2173 | niter = niter_for_single_dom_exit (data); |
2174 | if (!niter | |
2175 | || !zero_p (niter->may_be_zero)) | |
8b11a64c ZD |
2176 | return; |
2177 | ||
2178 | add_candidate_1 (data, NULL, NULL, false, IP_NORMAL, use, NULL_TREE); | |
2179 | } | |
2180 | ||
2181 | /* Adds candidates based on the uses. */ | |
2182 | ||
2183 | static void | |
2184 | add_derived_ivs_candidates (struct ivopts_data *data) | |
2185 | { | |
2186 | unsigned i; | |
2187 | ||
2188 | for (i = 0; i < n_iv_uses (data); i++) | |
2189 | { | |
2190 | struct iv_use *use = iv_use (data, i); | |
2191 | ||
2192 | if (!use) | |
2193 | continue; | |
2194 | ||
2195 | switch (use->type) | |
2196 | { | |
2197 | case USE_NONLINEAR_EXPR: | |
2198 | case USE_COMPARE: | |
9be872b7 | 2199 | case USE_ADDRESS: |
8b11a64c ZD |
2200 | /* Just add the ivs based on the value of the iv used here. */ |
2201 | add_iv_value_candidates (data, use->iv, use); | |
2202 | break; | |
2203 | ||
2204 | case USE_OUTER: | |
2205 | add_iv_value_candidates (data, use->iv, use); | |
2206 | ||
2207 | /* Additionally, add the pseudocandidate for the possibility to | |
2208 | replace the final value by a direct computation. */ | |
2209 | add_iv_outer_candidates (data, use); | |
2210 | break; | |
2211 | ||
8b11a64c | 2212 | default: |
1e128c5f | 2213 | gcc_unreachable (); |
8b11a64c ZD |
2214 | } |
2215 | } | |
2216 | } | |
2217 | ||
b1b02be2 ZD |
2218 | /* Record important candidates and add them to related_cands bitmaps |
2219 | if needed. */ | |
2220 | ||
2221 | static void | |
2222 | record_important_candidates (struct ivopts_data *data) | |
2223 | { | |
2224 | unsigned i; | |
2225 | struct iv_use *use; | |
2226 | ||
2227 | for (i = 0; i < n_iv_cands (data); i++) | |
2228 | { | |
2229 | struct iv_cand *cand = iv_cand (data, i); | |
2230 | ||
2231 | if (cand->important) | |
2232 | bitmap_set_bit (data->important_candidates, i); | |
2233 | } | |
2234 | ||
2235 | data->consider_all_candidates = (n_iv_cands (data) | |
2236 | <= CONSIDER_ALL_CANDIDATES_BOUND); | |
2237 | ||
2238 | if (data->consider_all_candidates) | |
2239 | { | |
2240 | /* We will not need "related_cands" bitmaps in this case, | |
2241 | so release them to decrease peak memory consumption. */ | |
2242 | for (i = 0; i < n_iv_uses (data); i++) | |
2243 | { | |
2244 | use = iv_use (data, i); | |
8bdbfff5 | 2245 | BITMAP_FREE (use->related_cands); |
b1b02be2 ZD |
2246 | } |
2247 | } | |
2248 | else | |
2249 | { | |
2250 | /* Add important candidates to the related_cands bitmaps. */ | |
2251 | for (i = 0; i < n_iv_uses (data); i++) | |
2252 | bitmap_ior_into (iv_use (data, i)->related_cands, | |
2253 | data->important_candidates); | |
2254 | } | |
2255 | } | |
2256 | ||
8b11a64c ZD |
2257 | /* Finds the candidates for the induction variables. */ |
2258 | ||
2259 | static void | |
2260 | find_iv_candidates (struct ivopts_data *data) | |
2261 | { | |
2262 | /* Add commonly used ivs. */ | |
2263 | add_standard_iv_candidates (data); | |
2264 | ||
2265 | /* Add old induction variables. */ | |
2266 | add_old_ivs_candidates (data); | |
2267 | ||
2268 | /* Add induction variables derived from uses. */ | |
2269 | add_derived_ivs_candidates (data); | |
b1b02be2 ZD |
2270 | |
2271 | /* Record the important candidates. */ | |
2272 | record_important_candidates (data); | |
8b11a64c ZD |
2273 | } |
2274 | ||
2275 | /* Allocates the data structure mapping the (use, candidate) pairs to costs. | |
2276 | If consider_all_candidates is true, we use a two-dimensional array, otherwise | |
2277 | we allocate a simple list to every use. */ | |
2278 | ||
2279 | static void | |
2280 | alloc_use_cost_map (struct ivopts_data *data) | |
2281 | { | |
b1b02be2 | 2282 | unsigned i, size, s, j; |
8b11a64c ZD |
2283 | |
2284 | for (i = 0; i < n_iv_uses (data); i++) | |
2285 | { | |
2286 | struct iv_use *use = iv_use (data, i); | |
87c476a2 | 2287 | bitmap_iterator bi; |
8b11a64c ZD |
2288 | |
2289 | if (data->consider_all_candidates) | |
b1b02be2 | 2290 | size = n_iv_cands (data); |
8b11a64c ZD |
2291 | else |
2292 | { | |
b1b02be2 | 2293 | s = 0; |
87c476a2 ZD |
2294 | EXECUTE_IF_SET_IN_BITMAP (use->related_cands, 0, j, bi) |
2295 | { | |
b1b02be2 | 2296 | s++; |
87c476a2 | 2297 | } |
b1b02be2 ZD |
2298 | |
2299 | /* Round up to the power of two, so that moduling by it is fast. */ | |
2300 | for (size = 1; size < s; size <<= 1) | |
2301 | continue; | |
8b11a64c ZD |
2302 | } |
2303 | ||
b1b02be2 | 2304 | use->n_map_members = size; |
8b11a64c ZD |
2305 | use->cost_map = xcalloc (size, sizeof (struct cost_pair)); |
2306 | } | |
2307 | } | |
2308 | ||
2309 | /* Sets cost of (USE, CANDIDATE) pair to COST and record that it depends | |
f5f12961 ZD |
2310 | on invariants DEPENDS_ON and that the value used in expressing it |
2311 | is VALUE.*/ | |
8b11a64c ZD |
2312 | |
2313 | static void | |
2314 | set_use_iv_cost (struct ivopts_data *data, | |
2315 | struct iv_use *use, struct iv_cand *cand, unsigned cost, | |
f5f12961 | 2316 | bitmap depends_on, tree value) |
8b11a64c | 2317 | { |
b1b02be2 ZD |
2318 | unsigned i, s; |
2319 | ||
2320 | if (cost == INFTY) | |
8b11a64c | 2321 | { |
8bdbfff5 | 2322 | BITMAP_FREE (depends_on); |
b1b02be2 | 2323 | return; |
8b11a64c ZD |
2324 | } |
2325 | ||
2326 | if (data->consider_all_candidates) | |
2327 | { | |
2328 | use->cost_map[cand->id].cand = cand; | |
2329 | use->cost_map[cand->id].cost = cost; | |
2330 | use->cost_map[cand->id].depends_on = depends_on; | |
f5f12961 | 2331 | use->cost_map[cand->id].value = value; |
8b11a64c ZD |
2332 | return; |
2333 | } | |
2334 | ||
b1b02be2 ZD |
2335 | /* n_map_members is a power of two, so this computes modulo. */ |
2336 | s = cand->id & (use->n_map_members - 1); | |
2337 | for (i = s; i < use->n_map_members; i++) | |
2338 | if (!use->cost_map[i].cand) | |
2339 | goto found; | |
2340 | for (i = 0; i < s; i++) | |
2341 | if (!use->cost_map[i].cand) | |
2342 | goto found; | |
2343 | ||
2344 | gcc_unreachable (); | |
8b11a64c | 2345 | |
b1b02be2 ZD |
2346 | found: |
2347 | use->cost_map[i].cand = cand; | |
2348 | use->cost_map[i].cost = cost; | |
2349 | use->cost_map[i].depends_on = depends_on; | |
f5f12961 | 2350 | use->cost_map[i].value = value; |
8b11a64c ZD |
2351 | } |
2352 | ||
b1b02be2 | 2353 | /* Gets cost of (USE, CANDIDATE) pair. */ |
8b11a64c | 2354 | |
b1b02be2 ZD |
2355 | static struct cost_pair * |
2356 | get_use_iv_cost (struct ivopts_data *data, struct iv_use *use, | |
2357 | struct iv_cand *cand) | |
8b11a64c | 2358 | { |
b1b02be2 ZD |
2359 | unsigned i, s; |
2360 | struct cost_pair *ret; | |
8b11a64c ZD |
2361 | |
2362 | if (!cand) | |
b1b02be2 | 2363 | return NULL; |
8b11a64c ZD |
2364 | |
2365 | if (data->consider_all_candidates) | |
8b11a64c | 2366 | { |
b1b02be2 ZD |
2367 | ret = use->cost_map + cand->id; |
2368 | if (!ret->cand) | |
2369 | return NULL; | |
8b11a64c | 2370 | |
b1b02be2 | 2371 | return ret; |
8b11a64c | 2372 | } |
b1b02be2 ZD |
2373 | |
2374 | /* n_map_members is a power of two, so this computes modulo. */ | |
2375 | s = cand->id & (use->n_map_members - 1); | |
2376 | for (i = s; i < use->n_map_members; i++) | |
2377 | if (use->cost_map[i].cand == cand) | |
2378 | return use->cost_map + i; | |
8b11a64c | 2379 | |
b1b02be2 ZD |
2380 | for (i = 0; i < s; i++) |
2381 | if (use->cost_map[i].cand == cand) | |
2382 | return use->cost_map + i; | |
2383 | ||
2384 | return NULL; | |
8b11a64c ZD |
2385 | } |
2386 | ||
2387 | /* Returns estimate on cost of computing SEQ. */ | |
2388 | ||
2389 | static unsigned | |
2390 | seq_cost (rtx seq) | |
2391 | { | |
2392 | unsigned cost = 0; | |
2393 | rtx set; | |
2394 | ||
2395 | for (; seq; seq = NEXT_INSN (seq)) | |
2396 | { | |
2397 | set = single_set (seq); | |
2398 | if (set) | |
2399 | cost += rtx_cost (set, SET); | |
2400 | else | |
2401 | cost++; | |
2402 | } | |
2403 | ||
2404 | return cost; | |
2405 | } | |
2406 | ||
8679c649 JH |
2407 | /* Produce DECL_RTL for object obj so it looks like it is stored in memory. */ |
2408 | static rtx | |
2409 | produce_memory_decl_rtl (tree obj, int *regno) | |
2410 | { | |
2411 | rtx x; | |
e16acfcd NS |
2412 | |
2413 | gcc_assert (obj); | |
8679c649 JH |
2414 | if (TREE_STATIC (obj) || DECL_EXTERNAL (obj)) |
2415 | { | |
2416 | const char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (obj)); | |
2417 | x = gen_rtx_SYMBOL_REF (Pmode, name); | |
2418 | } | |
2419 | else | |
2420 | x = gen_raw_REG (Pmode, (*regno)++); | |
2421 | ||
2422 | return gen_rtx_MEM (DECL_MODE (obj), x); | |
2423 | } | |
2424 | ||
8b11a64c ZD |
2425 | /* Prepares decl_rtl for variables referred in *EXPR_P. Callback for |
2426 | walk_tree. DATA contains the actual fake register number. */ | |
2427 | ||
2428 | static tree | |
2429 | prepare_decl_rtl (tree *expr_p, int *ws, void *data) | |
2430 | { | |
2431 | tree obj = NULL_TREE; | |
2432 | rtx x = NULL_RTX; | |
2433 | int *regno = data; | |
2434 | ||
2435 | switch (TREE_CODE (*expr_p)) | |
2436 | { | |
8679c649 JH |
2437 | case ADDR_EXPR: |
2438 | for (expr_p = &TREE_OPERAND (*expr_p, 0); | |
afe84921 RH |
2439 | handled_component_p (*expr_p); |
2440 | expr_p = &TREE_OPERAND (*expr_p, 0)) | |
2441 | continue; | |
8679c649 JH |
2442 | obj = *expr_p; |
2443 | if (DECL_P (obj)) | |
2444 | x = produce_memory_decl_rtl (obj, regno); | |
2445 | break; | |
2446 | ||
8b11a64c ZD |
2447 | case SSA_NAME: |
2448 | *ws = 0; | |
2449 | obj = SSA_NAME_VAR (*expr_p); | |
2450 | if (!DECL_RTL_SET_P (obj)) | |
2451 | x = gen_raw_REG (DECL_MODE (obj), (*regno)++); | |
2452 | break; | |
2453 | ||
2454 | case VAR_DECL: | |
2455 | case PARM_DECL: | |
2456 | case RESULT_DECL: | |
2457 | *ws = 0; | |
2458 | obj = *expr_p; | |
2459 | ||
2460 | if (DECL_RTL_SET_P (obj)) | |
2461 | break; | |
2462 | ||
2463 | if (DECL_MODE (obj) == BLKmode) | |
8679c649 | 2464 | x = produce_memory_decl_rtl (obj, regno); |
8b11a64c ZD |
2465 | else |
2466 | x = gen_raw_REG (DECL_MODE (obj), (*regno)++); | |
2467 | ||
2468 | break; | |
2469 | ||
2470 | default: | |
2471 | break; | |
2472 | } | |
2473 | ||
2474 | if (x) | |
2475 | { | |
69ebd99d | 2476 | VEC_safe_push (tree, heap, decl_rtl_to_reset, obj); |
8b11a64c ZD |
2477 | SET_DECL_RTL (obj, x); |
2478 | } | |
2479 | ||
2480 | return NULL_TREE; | |
2481 | } | |
2482 | ||
2483 | /* Determines cost of the computation of EXPR. */ | |
2484 | ||
2485 | static unsigned | |
2486 | computation_cost (tree expr) | |
2487 | { | |
2488 | rtx seq, rslt; | |
2489 | tree type = TREE_TYPE (expr); | |
2490 | unsigned cost; | |
1d27fed4 DD |
2491 | /* Avoid using hard regs in ways which may be unsupported. */ |
2492 | int regno = LAST_VIRTUAL_REGISTER + 1; | |
8b11a64c ZD |
2493 | |
2494 | walk_tree (&expr, prepare_decl_rtl, ®no, NULL); | |
2495 | start_sequence (); | |
2496 | rslt = expand_expr (expr, NULL_RTX, TYPE_MODE (type), EXPAND_NORMAL); | |
2497 | seq = get_insns (); | |
2498 | end_sequence (); | |
2499 | ||
2500 | cost = seq_cost (seq); | |
2ca202e7 | 2501 | if (MEM_P (rslt)) |
8b11a64c ZD |
2502 | cost += address_cost (XEXP (rslt, 0), TYPE_MODE (type)); |
2503 | ||
2504 | return cost; | |
2505 | } | |
2506 | ||
2507 | /* Returns variable containing the value of candidate CAND at statement AT. */ | |
2508 | ||
2509 | static tree | |
2510 | var_at_stmt (struct loop *loop, struct iv_cand *cand, tree stmt) | |
2511 | { | |
2512 | if (stmt_after_increment (loop, cand, stmt)) | |
2513 | return cand->var_after; | |
2514 | else | |
2515 | return cand->var_before; | |
2516 | } | |
2517 | ||
9be872b7 ZD |
2518 | /* Return the most significant (sign) bit of T. Similar to tree_int_cst_msb, |
2519 | but the bit is determined from TYPE_PRECISION, not MODE_BITSIZE. */ | |
2520 | ||
d7bf3bcf | 2521 | int |
9be872b7 ZD |
2522 | tree_int_cst_sign_bit (tree t) |
2523 | { | |
2524 | unsigned bitno = TYPE_PRECISION (TREE_TYPE (t)) - 1; | |
2525 | unsigned HOST_WIDE_INT w; | |
2526 | ||
2527 | if (bitno < HOST_BITS_PER_WIDE_INT) | |
2528 | w = TREE_INT_CST_LOW (t); | |
2529 | else | |
2530 | { | |
2531 | w = TREE_INT_CST_HIGH (t); | |
2532 | bitno -= HOST_BITS_PER_WIDE_INT; | |
2533 | } | |
2534 | ||
2535 | return (w >> bitno) & 1; | |
2536 | } | |
2537 | ||
2538 | /* If we can prove that TOP = cst * BOT for some constant cst in TYPE, | |
2539 | return cst. Otherwise return NULL_TREE. */ | |
2540 | ||
2541 | static tree | |
2542 | constant_multiple_of (tree type, tree top, tree bot) | |
2543 | { | |
2544 | tree res, mby, p0, p1; | |
2545 | enum tree_code code; | |
2546 | bool negate; | |
2547 | ||
2548 | STRIP_NOPS (top); | |
2549 | STRIP_NOPS (bot); | |
2550 | ||
2551 | if (operand_equal_p (top, bot, 0)) | |
2552 | return build_int_cst (type, 1); | |
2553 | ||
2554 | code = TREE_CODE (top); | |
2555 | switch (code) | |
2556 | { | |
2557 | case MULT_EXPR: | |
2558 | mby = TREE_OPERAND (top, 1); | |
2559 | if (TREE_CODE (mby) != INTEGER_CST) | |
2560 | return NULL_TREE; | |
2561 | ||
2562 | res = constant_multiple_of (type, TREE_OPERAND (top, 0), bot); | |
2563 | if (!res) | |
2564 | return NULL_TREE; | |
2565 | ||
2566 | return fold_binary_to_constant (MULT_EXPR, type, res, | |
2567 | fold_convert (type, mby)); | |
2568 | ||
2569 | case PLUS_EXPR: | |
2570 | case MINUS_EXPR: | |
2571 | p0 = constant_multiple_of (type, TREE_OPERAND (top, 0), bot); | |
2572 | if (!p0) | |
2573 | return NULL_TREE; | |
2574 | p1 = constant_multiple_of (type, TREE_OPERAND (top, 1), bot); | |
2575 | if (!p1) | |
2576 | return NULL_TREE; | |
2577 | ||
2578 | return fold_binary_to_constant (code, type, p0, p1); | |
2579 | ||
2580 | case INTEGER_CST: | |
2581 | if (TREE_CODE (bot) != INTEGER_CST) | |
2582 | return NULL_TREE; | |
2583 | ||
2584 | bot = fold_convert (type, bot); | |
2585 | top = fold_convert (type, top); | |
2586 | ||
2587 | /* If BOT seems to be negative, try dividing by -BOT instead, and negate | |
2588 | the result afterwards. */ | |
2589 | if (tree_int_cst_sign_bit (bot)) | |
2590 | { | |
2591 | negate = true; | |
2592 | bot = fold_unary_to_constant (NEGATE_EXPR, type, bot); | |
2593 | } | |
2594 | else | |
2595 | negate = false; | |
2596 | ||
2597 | /* Ditto for TOP. */ | |
2598 | if (tree_int_cst_sign_bit (top)) | |
2599 | { | |
2600 | negate = !negate; | |
2601 | top = fold_unary_to_constant (NEGATE_EXPR, type, top); | |
2602 | } | |
2603 | ||
2604 | if (!zero_p (fold_binary_to_constant (TRUNC_MOD_EXPR, type, top, bot))) | |
2605 | return NULL_TREE; | |
2606 | ||
2607 | res = fold_binary_to_constant (EXACT_DIV_EXPR, type, top, bot); | |
2608 | if (negate) | |
2609 | res = fold_unary_to_constant (NEGATE_EXPR, type, res); | |
2610 | return res; | |
2611 | ||
2612 | default: | |
2613 | return NULL_TREE; | |
2614 | } | |
2615 | } | |
2616 | ||
2617 | /* Affine combination of trees. We keep track of at most MAX_AFF_ELTS elements | |
2618 | to make things simpler; this is sufficient in most cases. */ | |
2619 | ||
2620 | #define MAX_AFF_ELTS 8 | |
2621 | ||
2622 | struct affine_tree_combination | |
2623 | { | |
2624 | /* Type of the result of the combination. */ | |
2625 | tree type; | |
2626 | ||
2627 | /* Mask modulo that the operations are performed. */ | |
2628 | unsigned HOST_WIDE_INT mask; | |
2629 | ||
2630 | /* Constant offset. */ | |
2631 | unsigned HOST_WIDE_INT offset; | |
2632 | ||
2633 | /* Number of elements of the combination. */ | |
2634 | unsigned n; | |
2635 | ||
2636 | /* Elements and their coefficients. */ | |
2637 | tree elts[MAX_AFF_ELTS]; | |
2638 | unsigned HOST_WIDE_INT coefs[MAX_AFF_ELTS]; | |
2639 | ||
2640 | /* Remainder of the expression. */ | |
2641 | tree rest; | |
2642 | }; | |
2643 | ||
2644 | /* Sets COMB to CST. */ | |
2645 | ||
2646 | static void | |
2647 | aff_combination_const (struct affine_tree_combination *comb, tree type, | |
2648 | unsigned HOST_WIDE_INT cst) | |
2649 | { | |
2650 | unsigned prec = TYPE_PRECISION (type); | |
2651 | ||
2652 | comb->type = type; | |
2653 | comb->mask = (((unsigned HOST_WIDE_INT) 2 << (prec - 1)) - 1); | |
2654 | ||
2655 | comb->n = 0; | |
2656 | comb->rest = NULL_TREE; | |
2657 | comb->offset = cst & comb->mask; | |
2658 | } | |
2659 | ||
2660 | /* Sets COMB to single element ELT. */ | |
2661 | ||
2662 | static void | |
2663 | aff_combination_elt (struct affine_tree_combination *comb, tree type, tree elt) | |
2664 | { | |
2665 | unsigned prec = TYPE_PRECISION (type); | |
2666 | ||
2667 | comb->type = type; | |
2668 | comb->mask = (((unsigned HOST_WIDE_INT) 2 << (prec - 1)) - 1); | |
2669 | ||
2670 | comb->n = 1; | |
2671 | comb->elts[0] = elt; | |
2672 | comb->coefs[0] = 1; | |
2673 | comb->rest = NULL_TREE; | |
2674 | comb->offset = 0; | |
2675 | } | |
2676 | ||
2677 | /* Scales COMB by SCALE. */ | |
2678 | ||
2679 | static void | |
2680 | aff_combination_scale (struct affine_tree_combination *comb, | |
2681 | unsigned HOST_WIDE_INT scale) | |
2682 | { | |
2683 | unsigned i, j; | |
2684 | ||
2685 | if (scale == 1) | |
2686 | return; | |
2687 | ||
2688 | if (scale == 0) | |
2689 | { | |
2690 | aff_combination_const (comb, comb->type, 0); | |
2691 | return; | |
2692 | } | |
2693 | ||
2694 | comb->offset = (scale * comb->offset) & comb->mask; | |
2695 | for (i = 0, j = 0; i < comb->n; i++) | |
2696 | { | |
2697 | comb->coefs[j] = (scale * comb->coefs[i]) & comb->mask; | |
2698 | comb->elts[j] = comb->elts[i]; | |
2699 | if (comb->coefs[j] != 0) | |
2700 | j++; | |
2701 | } | |
2702 | comb->n = j; | |
2703 | ||
2704 | if (comb->rest) | |
2705 | { | |
2706 | if (comb->n < MAX_AFF_ELTS) | |
2707 | { | |
2708 | comb->coefs[comb->n] = scale; | |
2709 | comb->elts[comb->n] = comb->rest; | |
2710 | comb->rest = NULL_TREE; | |
2711 | comb->n++; | |
2712 | } | |
2713 | else | |
2714 | comb->rest = fold_build2 (MULT_EXPR, comb->type, comb->rest, | |
2715 | build_int_cst_type (comb->type, scale)); | |
2716 | } | |
2717 | } | |
2718 | ||
2719 | /* Adds ELT * SCALE to COMB. */ | |
2720 | ||
2721 | static void | |
2722 | aff_combination_add_elt (struct affine_tree_combination *comb, tree elt, | |
2723 | unsigned HOST_WIDE_INT scale) | |
2724 | { | |
2725 | unsigned i; | |
2726 | ||
2727 | if (scale == 0) | |
2728 | return; | |
2729 | ||
2730 | for (i = 0; i < comb->n; i++) | |
2731 | if (operand_equal_p (comb->elts[i], elt, 0)) | |
2732 | { | |
2733 | comb->coefs[i] = (comb->coefs[i] + scale) & comb->mask; | |
2734 | if (comb->coefs[i]) | |
2735 | return; | |
2736 | ||
2737 | comb->n--; | |
2738 | comb->coefs[i] = comb->coefs[comb->n]; | |
2739 | comb->elts[i] = comb->elts[comb->n]; | |
2740 | return; | |
2741 | } | |
2742 | if (comb->n < MAX_AFF_ELTS) | |
2743 | { | |
2744 | comb->coefs[comb->n] = scale; | |
2745 | comb->elts[comb->n] = elt; | |
2746 | comb->n++; | |
2747 | return; | |
2748 | } | |
2749 | ||
2750 | if (scale == 1) | |
2751 | elt = fold_convert (comb->type, elt); | |
2752 | else | |
2753 | elt = fold_build2 (MULT_EXPR, comb->type, | |
2754 | fold_convert (comb->type, elt), | |
2755 | build_int_cst_type (comb->type, scale)); | |
2756 | ||
2757 | if (comb->rest) | |
2758 | comb->rest = fold_build2 (PLUS_EXPR, comb->type, comb->rest, elt); | |
2759 | else | |
2760 | comb->rest = elt; | |
2761 | } | |
2762 | ||
2763 | /* Adds COMB2 to COMB1. */ | |
2764 | ||
2765 | static void | |
2766 | aff_combination_add (struct affine_tree_combination *comb1, | |
2767 | struct affine_tree_combination *comb2) | |
2768 | { | |
2769 | unsigned i; | |
2770 | ||
2771 | comb1->offset = (comb1->offset + comb2->offset) & comb1->mask; | |
2772 | for (i = 0; i < comb2-> n; i++) | |
2773 | aff_combination_add_elt (comb1, comb2->elts[i], comb2->coefs[i]); | |
2774 | if (comb2->rest) | |
2775 | aff_combination_add_elt (comb1, comb2->rest, 1); | |
2776 | } | |
2777 | ||
2778 | /* Splits EXPR into an affine combination of parts. */ | |
2779 | ||
2780 | static void | |
2781 | tree_to_aff_combination (tree expr, tree type, | |
2782 | struct affine_tree_combination *comb) | |
2783 | { | |
2784 | struct affine_tree_combination tmp; | |
2785 | enum tree_code code; | |
2786 | tree cst, core, toffset; | |
2787 | HOST_WIDE_INT bitpos, bitsize; | |
2788 | enum machine_mode mode; | |
2789 | int unsignedp, volatilep; | |
2790 | ||
2791 | STRIP_NOPS (expr); | |
2792 | ||
2793 | code = TREE_CODE (expr); | |
2794 | switch (code) | |
2795 | { | |
2796 | case INTEGER_CST: | |
2797 | aff_combination_const (comb, type, int_cst_value (expr)); | |
2798 | return; | |
2799 | ||
2800 | case PLUS_EXPR: | |
2801 | case MINUS_EXPR: | |
2802 | tree_to_aff_combination (TREE_OPERAND (expr, 0), type, comb); | |
2803 | tree_to_aff_combination (TREE_OPERAND (expr, 1), type, &tmp); | |
2804 | if (code == MINUS_EXPR) | |
2805 | aff_combination_scale (&tmp, -1); | |
2806 | aff_combination_add (comb, &tmp); | |
2807 | return; | |
2808 | ||
2809 | case MULT_EXPR: | |
2810 | cst = TREE_OPERAND (expr, 1); | |
2811 | if (TREE_CODE (cst) != INTEGER_CST) | |
2812 | break; | |
2813 | tree_to_aff_combination (TREE_OPERAND (expr, 0), type, comb); | |
2814 | aff_combination_scale (comb, int_cst_value (cst)); | |
2815 | return; | |
2816 | ||
2817 | case NEGATE_EXPR: | |
2818 | tree_to_aff_combination (TREE_OPERAND (expr, 0), type, comb); | |
2819 | aff_combination_scale (comb, -1); | |
2820 | return; | |
2821 | ||
2822 | case ADDR_EXPR: | |
2823 | core = get_inner_reference (TREE_OPERAND (expr, 0), &bitsize, &bitpos, | |
2824 | &toffset, &mode, &unsignedp, &volatilep, | |
2825 | false); | |
2826 | if (bitpos % BITS_PER_UNIT != 0) | |
2827 | break; | |
2828 | aff_combination_const (comb, type, bitpos / BITS_PER_UNIT); | |
d5dc1717 | 2829 | core = build_fold_addr_expr (core); |
9be872b7 ZD |
2830 | if (TREE_CODE (core) == ADDR_EXPR) |
2831 | aff_combination_add_elt (comb, core, 1); | |
2832 | else | |
2833 | { | |
2834 | tree_to_aff_combination (core, type, &tmp); | |
2835 | aff_combination_add (comb, &tmp); | |
2836 | } | |
2837 | if (toffset) | |
2838 | { | |
2839 | tree_to_aff_combination (toffset, type, &tmp); | |
2840 | aff_combination_add (comb, &tmp); | |
2841 | } | |
2842 | return; | |
2843 | ||
2844 | default: | |
2845 | break; | |
2846 | } | |
2847 | ||
2848 | aff_combination_elt (comb, type, expr); | |
2849 | } | |
2850 | ||
2851 | /* Creates EXPR + ELT * SCALE in TYPE. MASK is the mask for width of TYPE. */ | |
2852 | ||
2853 | static tree | |
2854 | add_elt_to_tree (tree expr, tree type, tree elt, unsigned HOST_WIDE_INT scale, | |
2855 | unsigned HOST_WIDE_INT mask) | |
2856 | { | |
2857 | enum tree_code code; | |
2858 | ||
2859 | scale &= mask; | |
2860 | elt = fold_convert (type, elt); | |
2861 | ||
2862 | if (scale == 1) | |
2863 | { | |
2864 | if (!expr) | |
2865 | return elt; | |
2866 | ||
2867 | return fold_build2 (PLUS_EXPR, type, expr, elt); | |
2868 | } | |
2869 | ||
2870 | if (scale == mask) | |
2871 | { | |
2872 | if (!expr) | |
2873 | return fold_build1 (NEGATE_EXPR, type, elt); | |
2874 | ||
2875 | return fold_build2 (MINUS_EXPR, type, expr, elt); | |
2876 | } | |
2877 | ||
2878 | if (!expr) | |
2879 | return fold_build2 (MULT_EXPR, type, elt, | |
2880 | build_int_cst_type (type, scale)); | |
2881 | ||
2882 | if ((scale | (mask >> 1)) == mask) | |
2883 | { | |
2884 | /* Scale is negative. */ | |
2885 | code = MINUS_EXPR; | |
2886 | scale = (-scale) & mask; | |
2887 | } | |
2888 | else | |
2889 | code = PLUS_EXPR; | |
2890 | ||
2891 | elt = fold_build2 (MULT_EXPR, type, elt, | |
2892 | build_int_cst_type (type, scale)); | |
2893 | return fold_build2 (code, type, expr, elt); | |
2894 | } | |
2895 | ||
2896 | /* Makes tree from the affine combination COMB. */ | |
2897 | ||
2898 | static tree | |
2899 | aff_combination_to_tree (struct affine_tree_combination *comb) | |
2900 | { | |
2901 | tree type = comb->type; | |
2902 | tree expr = comb->rest; | |
2903 | unsigned i; | |
2904 | unsigned HOST_WIDE_INT off, sgn; | |
2905 | ||
2906 | gcc_assert (comb->n == MAX_AFF_ELTS || comb->rest == NULL_TREE); | |
2907 | ||
2908 | for (i = 0; i < comb->n; i++) | |
2909 | expr = add_elt_to_tree (expr, type, comb->elts[i], comb->coefs[i], | |
2910 | comb->mask); | |
2911 | ||
2912 | if ((comb->offset | (comb->mask >> 1)) == comb->mask) | |
2913 | { | |
2914 | /* Offset is negative. */ | |
2915 | off = (-comb->offset) & comb->mask; | |
2916 | sgn = comb->mask; | |
2917 | } | |
2918 | else | |
2919 | { | |
2920 | off = comb->offset; | |
2921 | sgn = 1; | |
2922 | } | |
2923 | return add_elt_to_tree (expr, type, build_int_cst_type (type, off), sgn, | |
2924 | comb->mask); | |
2925 | } | |
2926 | ||
2927 | /* Folds X + RATIO * Y in TYPE. */ | |
2928 | ||
2929 | static tree | |
2930 | fold_affine_sum (tree type, tree x, tree y, HOST_WIDE_INT ratio) | |
2931 | { | |
2932 | enum tree_code code; | |
2933 | tree cst; | |
2934 | struct affine_tree_combination cx, cy; | |
2935 | ||
2936 | if (TYPE_PRECISION (type) > HOST_BITS_PER_WIDE_INT) | |
2937 | { | |
2938 | if (ratio == 1) | |
2939 | return fold_build2 (PLUS_EXPR, type, x, y); | |
2940 | if (ratio == -1) | |
2941 | return fold_build2 (MINUS_EXPR, type, x, y); | |
2942 | ||
2943 | if (ratio < 0) | |
2944 | { | |
2945 | code = MINUS_EXPR; | |
2946 | ratio = -ratio; | |
2947 | } | |
2948 | else | |
2949 | code = PLUS_EXPR; | |
2950 | ||
2951 | cst = build_int_cst_type (type, ratio); | |
2952 | y = fold_build2 (MULT_EXPR, type, y, cst); | |
2953 | return fold_build2 (code, type, x, y); | |
2954 | } | |
2955 | ||
2956 | tree_to_aff_combination (x, type, &cx); | |
2957 | tree_to_aff_combination (y, type, &cy); | |
2958 | aff_combination_scale (&cy, ratio); | |
2959 | aff_combination_add (&cx, &cy); | |
2960 | ||
2961 | return aff_combination_to_tree (&cx); | |
2962 | } | |
2963 | ||
8b11a64c ZD |
2964 | /* Determines the expression by that USE is expressed from induction variable |
2965 | CAND at statement AT in LOOP. */ | |
2966 | ||
2967 | static tree | |
2968 | get_computation_at (struct loop *loop, | |
2969 | struct iv_use *use, struct iv_cand *cand, tree at) | |
2970 | { | |
2f4675b4 ZD |
2971 | tree ubase = use->iv->base; |
2972 | tree ustep = use->iv->step; | |
2973 | tree cbase = cand->iv->base; | |
2974 | tree cstep = cand->iv->step; | |
8b11a64c ZD |
2975 | tree utype = TREE_TYPE (ubase), ctype = TREE_TYPE (cbase); |
2976 | tree uutype; | |
2977 | tree expr, delta; | |
2978 | tree ratio; | |
2979 | unsigned HOST_WIDE_INT ustepi, cstepi; | |
2980 | HOST_WIDE_INT ratioi; | |
2981 | ||
2982 | if (TYPE_PRECISION (utype) > TYPE_PRECISION (ctype)) | |
2983 | { | |
2984 | /* We do not have a precision to express the values of use. */ | |
2985 | return NULL_TREE; | |
2986 | } | |
2987 | ||
2988 | expr = var_at_stmt (loop, cand, at); | |
2989 | ||
2990 | if (TREE_TYPE (expr) != ctype) | |
2991 | { | |
2992 | /* This may happen with the original ivs. */ | |
2993 | expr = fold_convert (ctype, expr); | |
2994 | } | |
2995 | ||
2996 | if (TYPE_UNSIGNED (utype)) | |
2997 | uutype = utype; | |
2998 | else | |
2999 | { | |
3000 | uutype = unsigned_type_for (utype); | |
3001 | ubase = fold_convert (uutype, ubase); | |
3002 | ustep = fold_convert (uutype, ustep); | |
3003 | } | |
3004 | ||
3005 | if (uutype != ctype) | |
3006 | { | |
3007 | expr = fold_convert (uutype, expr); | |
3008 | cbase = fold_convert (uutype, cbase); | |
3009 | cstep = fold_convert (uutype, cstep); | |
3010 | } | |
3011 | ||
9be872b7 ZD |
3012 | if (cst_and_fits_in_hwi (cstep) |
3013 | && cst_and_fits_in_hwi (ustep)) | |
3014 | { | |
3015 | ustepi = int_cst_value (ustep); | |
3016 | cstepi = int_cst_value (cstep); | |
8b11a64c | 3017 | |
9be872b7 ZD |
3018 | if (!divide (TYPE_PRECISION (uutype), ustepi, cstepi, &ratioi)) |
3019 | { | |
3020 | /* TODO maybe consider case when ustep divides cstep and the ratio is | |
3021 | a power of 2 (so that the division is fast to execute)? We would | |
3022 | need to be much more careful with overflows etc. then. */ | |
3023 | return NULL_TREE; | |
3024 | } | |
8b11a64c | 3025 | |
9be872b7 ZD |
3026 | ratio = build_int_cst_type (uutype, ratioi); |
3027 | } | |
3028 | else | |
8b11a64c | 3029 | { |
9be872b7 ZD |
3030 | ratio = constant_multiple_of (uutype, ustep, cstep); |
3031 | if (!ratio) | |
3032 | return NULL_TREE; | |
3033 | ||
3034 | /* Ratioi is only used to detect special cases when the multiplicative | |
3035 | factor is 1 or -1, so if we cannot convert ratio to HOST_WIDE_INT, | |
3036 | we may set it to 0. We prefer cst_and_fits_in_hwi/int_cst_value | |
3037 | to integer_onep/integer_all_onesp, since the former ignores | |
3038 | TREE_OVERFLOW. */ | |
3039 | if (cst_and_fits_in_hwi (ratio)) | |
3040 | ratioi = int_cst_value (ratio); | |
3041 | else if (integer_onep (ratio)) | |
3042 | ratioi = 1; | |
3043 | else if (integer_all_onesp (ratio)) | |
3044 | ratioi = -1; | |
3045 | else | |
3046 | ratioi = 0; | |
8b11a64c ZD |
3047 | } |
3048 | ||
3049 | /* We may need to shift the value if we are after the increment. */ | |
3050 | if (stmt_after_increment (loop, cand, at)) | |
3051 | cbase = fold (build2 (PLUS_EXPR, uutype, cbase, cstep)); | |
3052 | ||
b0a168b6 ZD |
3053 | /* use = ubase - ratio * cbase + ratio * var. |
3054 | ||
3055 | In general case ubase + ratio * (var - cbase) could be better (one less | |
3056 | multiplication), but often it is possible to eliminate redundant parts | |
3057 | of computations from (ubase - ratio * cbase) term, and if it does not | |
3058 | happen, fold is able to apply the distributive law to obtain this form | |
3059 | anyway. */ | |
8b11a64c ZD |
3060 | |
3061 | if (ratioi == 1) | |
3062 | { | |
9be872b7 ZD |
3063 | delta = fold_affine_sum (uutype, ubase, cbase, -1); |
3064 | expr = fold_build2 (PLUS_EXPR, uutype, expr, delta); | |
8b11a64c ZD |
3065 | } |
3066 | else if (ratioi == -1) | |
3067 | { | |
9be872b7 ZD |
3068 | delta = fold_affine_sum (uutype, ubase, cbase, 1); |
3069 | expr = fold_build2 (MINUS_EXPR, uutype, delta, expr); | |
8b11a64c | 3070 | } |
b0a168b6 | 3071 | else |
8b11a64c | 3072 | { |
9be872b7 ZD |
3073 | if (ratioi) |
3074 | delta = fold_affine_sum (uutype, ubase, cbase, -ratioi); | |
3075 | else | |
3076 | { | |
3077 | delta = fold_build2 (MULT_EXPR, uutype, ratio, cbase); | |
3078 | delta = fold_affine_sum (uutype, ubase, delta, -1); | |
3079 | } | |
3080 | expr = fold_build2 (MULT_EXPR, uutype, ratio, expr); | |
3081 | expr = fold_build2 (PLUS_EXPR, uutype, delta, expr); | |
8b11a64c | 3082 | } |
8b11a64c ZD |
3083 | |
3084 | return fold_convert (utype, expr); | |
3085 | } | |
3086 | ||
3087 | /* Determines the expression by that USE is expressed from induction variable | |
3088 | CAND in LOOP. */ | |
3089 | ||
3090 | static tree | |
3091 | get_computation (struct loop *loop, struct iv_use *use, struct iv_cand *cand) | |
3092 | { | |
3093 | return get_computation_at (loop, use, cand, use->stmt); | |
3094 | } | |
3095 | ||
8b11a64c ZD |
3096 | /* Returns cost of addition in MODE. */ |
3097 | ||
3098 | static unsigned | |
3099 | add_cost (enum machine_mode mode) | |
3100 | { | |
3101 | static unsigned costs[NUM_MACHINE_MODES]; | |
3102 | rtx seq; | |
3103 | unsigned cost; | |
3104 | ||
3105 | if (costs[mode]) | |
3106 | return costs[mode]; | |
3107 | ||
3108 | start_sequence (); | |
3109 | force_operand (gen_rtx_fmt_ee (PLUS, mode, | |
3110 | gen_raw_REG (mode, FIRST_PSEUDO_REGISTER), | |
3111 | gen_raw_REG (mode, FIRST_PSEUDO_REGISTER + 1)), | |
3112 | NULL_RTX); | |
3113 | seq = get_insns (); | |
3114 | end_sequence (); | |
3115 | ||
3116 | cost = seq_cost (seq); | |
3117 | if (!cost) | |
3118 | cost = 1; | |
3119 | ||
3120 | costs[mode] = cost; | |
3121 | ||
3122 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3123 | fprintf (dump_file, "Addition in %s costs %d\n", | |
3124 | GET_MODE_NAME (mode), cost); | |
3125 | return cost; | |
3126 | } | |
3127 | ||
3128 | /* Entry in a hashtable of already known costs for multiplication. */ | |
3129 | struct mbc_entry | |
3130 | { | |
3131 | HOST_WIDE_INT cst; /* The constant to multiply by. */ | |
3132 | enum machine_mode mode; /* In mode. */ | |
3133 | unsigned cost; /* The cost. */ | |
3134 | }; | |
3135 | ||
3136 | /* Counts hash value for the ENTRY. */ | |
3137 | ||
3138 | static hashval_t | |
3139 | mbc_entry_hash (const void *entry) | |
3140 | { | |
3141 | const struct mbc_entry *e = entry; | |
3142 | ||
3143 | return 57 * (hashval_t) e->mode + (hashval_t) (e->cst % 877); | |
3144 | } | |
3145 | ||
3146 | /* Compares the hash table entries ENTRY1 and ENTRY2. */ | |
3147 | ||
3148 | static int | |
3149 | mbc_entry_eq (const void *entry1, const void *entry2) | |
3150 | { | |
3151 | const struct mbc_entry *e1 = entry1; | |
3152 | const struct mbc_entry *e2 = entry2; | |
3153 | ||
3154 | return (e1->mode == e2->mode | |
3155 | && e1->cst == e2->cst); | |
3156 | } | |
3157 | ||
3158 | /* Returns cost of multiplication by constant CST in MODE. */ | |
3159 | ||
3160 | static unsigned | |
3161 | multiply_by_cost (HOST_WIDE_INT cst, enum machine_mode mode) | |
3162 | { | |
3163 | static htab_t costs; | |
3164 | struct mbc_entry **cached, act; | |
3165 | rtx seq; | |
3166 | unsigned cost; | |
3167 | ||
3168 | if (!costs) | |
3169 | costs = htab_create (100, mbc_entry_hash, mbc_entry_eq, free); | |
3170 | ||
3171 | act.mode = mode; | |
3172 | act.cst = cst; | |
3173 | cached = (struct mbc_entry **) htab_find_slot (costs, &act, INSERT); | |
3174 | if (*cached) | |
3175 | return (*cached)->cost; | |
3176 | ||
3177 | *cached = xmalloc (sizeof (struct mbc_entry)); | |
3178 | (*cached)->mode = mode; | |
3179 | (*cached)->cst = cst; | |
3180 | ||
3181 | start_sequence (); | |
3182 | expand_mult (mode, gen_raw_REG (mode, FIRST_PSEUDO_REGISTER), GEN_INT (cst), | |
3183 | NULL_RTX, 0); | |
3184 | seq = get_insns (); | |
3185 | end_sequence (); | |
3186 | ||
3187 | cost = seq_cost (seq); | |
3188 | ||
3189 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3190 | fprintf (dump_file, "Multiplication by %d in %s costs %d\n", | |
3191 | (int) cst, GET_MODE_NAME (mode), cost); | |
3192 | ||
3193 | (*cached)->cost = cost; | |
3194 | ||
3195 | return cost; | |
3196 | } | |
3197 | ||
3198 | /* Returns cost of address in shape symbol + var + OFFSET + RATIO * index. | |
3199 | If SYMBOL_PRESENT is false, symbol is omitted. If VAR_PRESENT is false, | |
3200 | variable is omitted. The created memory accesses MODE. | |
3201 | ||
3202 | TODO -- there must be some better way. This all is quite crude. */ | |
3203 | ||
3204 | static unsigned | |
3205 | get_address_cost (bool symbol_present, bool var_present, | |
3206 | unsigned HOST_WIDE_INT offset, HOST_WIDE_INT ratio) | |
3207 | { | |
3208 | #define MAX_RATIO 128 | |
3209 | static sbitmap valid_mult; | |
3210 | static HOST_WIDE_INT rat, off; | |
3211 | static HOST_WIDE_INT min_offset, max_offset; | |
3212 | static unsigned costs[2][2][2][2]; | |
3213 | unsigned cost, acost; | |
3214 | rtx seq, addr, base; | |
3215 | bool offset_p, ratio_p; | |
3216 | rtx reg1; | |
3217 | HOST_WIDE_INT s_offset; | |
3218 | unsigned HOST_WIDE_INT mask; | |
3219 | unsigned bits; | |
3220 | ||
3221 | if (!valid_mult) | |
3222 | { | |
3223 | HOST_WIDE_INT i; | |
3224 | ||
3225 | reg1 = gen_raw_REG (Pmode, FIRST_PSEUDO_REGISTER); | |
3226 | ||
3227 | addr = gen_rtx_fmt_ee (PLUS, Pmode, reg1, NULL_RTX); | |
3228 | for (i = 1; i <= 1 << 20; i <<= 1) | |
3229 | { | |
3230 | XEXP (addr, 1) = GEN_INT (i); | |
3231 | if (!memory_address_p (Pmode, addr)) | |
3232 | break; | |
3233 | } | |
3234 | max_offset = i >> 1; | |
3235 | off = max_offset; | |
3236 | ||
3237 | for (i = 1; i <= 1 << 20; i <<= 1) | |
3238 | { | |
3239 | XEXP (addr, 1) = GEN_INT (-i); | |
3240 | if (!memory_address_p (Pmode, addr)) | |
3241 | break; | |
3242 | } | |
3243 | min_offset = -(i >> 1); | |
3244 | ||
3245 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3246 | { | |
3247 | fprintf (dump_file, "get_address_cost:\n"); | |
3248 | fprintf (dump_file, " min offset %d\n", (int) min_offset); | |
3249 | fprintf (dump_file, " max offset %d\n", (int) max_offset); | |
3250 | } | |
3251 | ||
3252 | valid_mult = sbitmap_alloc (2 * MAX_RATIO + 1); | |
3253 | sbitmap_zero (valid_mult); | |
3254 | rat = 1; | |
3255 | addr = gen_rtx_fmt_ee (MULT, Pmode, reg1, NULL_RTX); | |
3256 | for (i = -MAX_RATIO; i <= MAX_RATIO; i++) | |
3257 | { | |
3258 | XEXP (addr, 1) = GEN_INT (i); | |
3259 | if (memory_address_p (Pmode, addr)) | |
3260 | { | |
3261 | SET_BIT (valid_mult, i + MAX_RATIO); | |
3262 | rat = i; | |
3263 | } | |
3264 | } | |
3265 | ||
3266 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3267 | { | |
3268 | fprintf (dump_file, " allowed multipliers:"); | |
3269 | for (i = -MAX_RATIO; i <= MAX_RATIO; i++) | |
3270 | if (TEST_BIT (valid_mult, i + MAX_RATIO)) | |
3271 | fprintf (dump_file, " %d", (int) i); | |
3272 | fprintf (dump_file, "\n"); | |
3273 | fprintf (dump_file, "\n"); | |
3274 | } | |
3275 | } | |
3276 | ||
3277 | bits = GET_MODE_BITSIZE (Pmode); | |
3278 | mask = ~(~(unsigned HOST_WIDE_INT) 0 << (bits - 1) << 1); | |
3279 | offset &= mask; | |
3280 | if ((offset >> (bits - 1) & 1)) | |
3281 | offset |= ~mask; | |
3282 | s_offset = offset; | |
3283 | ||
3284 | cost = 0; | |
a85a9024 UW |
3285 | offset_p = (s_offset != 0 |
3286 | && min_offset <= s_offset && s_offset <= max_offset); | |
8b11a64c ZD |
3287 | ratio_p = (ratio != 1 |
3288 | && -MAX_RATIO <= ratio && ratio <= MAX_RATIO | |
3289 | && TEST_BIT (valid_mult, ratio + MAX_RATIO)); | |
3290 | ||
3291 | if (ratio != 1 && !ratio_p) | |
3292 | cost += multiply_by_cost (ratio, Pmode); | |
3293 | ||
3294 | if (s_offset && !offset_p && !symbol_present) | |
3295 | { | |
3296 | cost += add_cost (Pmode); | |
3297 | var_present = true; | |
3298 | } | |
3299 | ||
3300 | acost = costs[symbol_present][var_present][offset_p][ratio_p]; | |
3301 | if (!acost) | |
3302 | { | |
3303 | acost = 0; | |
3304 | ||
3305 | addr = gen_raw_REG (Pmode, FIRST_PSEUDO_REGISTER); | |
3306 | reg1 = gen_raw_REG (Pmode, FIRST_PSEUDO_REGISTER + 1); | |
3307 | if (ratio_p) | |
3308 | addr = gen_rtx_fmt_ee (MULT, Pmode, addr, GEN_INT (rat)); | |
3309 | ||
a85a9024 | 3310 | if (var_present) |
7299dbfb | 3311 | addr = gen_rtx_fmt_ee (PLUS, Pmode, addr, reg1); |
a85a9024 | 3312 | |
8b11a64c ZD |
3313 | if (symbol_present) |
3314 | { | |
3315 | base = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup ("")); | |
3316 | if (offset_p) | |
3317 | base = gen_rtx_fmt_e (CONST, Pmode, | |
3318 | gen_rtx_fmt_ee (PLUS, Pmode, | |
3319 | base, | |
3320 | GEN_INT (off))); | |
8b11a64c ZD |
3321 | } |
3322 | else if (offset_p) | |
3323 | base = GEN_INT (off); | |
3324 | else | |
3325 | base = NULL_RTX; | |
3326 | ||
3327 | if (base) | |
7299dbfb | 3328 | addr = gen_rtx_fmt_ee (PLUS, Pmode, addr, base); |
8b11a64c ZD |
3329 | |
3330 | start_sequence (); | |
3331 | addr = memory_address (Pmode, addr); | |
3332 | seq = get_insns (); | |
3333 | end_sequence (); | |
3334 | ||
3335 | acost = seq_cost (seq); | |
3336 | acost += address_cost (addr, Pmode); | |
3337 | ||
3338 | if (!acost) | |
3339 | acost = 1; | |
3340 | costs[symbol_present][var_present][offset_p][ratio_p] = acost; | |
3341 | } | |
3342 | ||
3343 | return cost + acost; | |
3344 | } | |
7299dbfb | 3345 | /* Estimates cost of forcing EXPR into a variable. DEPENDS_ON is a set of the |
8b11a64c ZD |
3346 | invariants the computation depends on. */ |
3347 | ||
3348 | static unsigned | |
3349 | force_var_cost (struct ivopts_data *data, | |
3350 | tree expr, bitmap *depends_on) | |
3351 | { | |
3352 | static bool costs_initialized = false; | |
3353 | static unsigned integer_cost; | |
3354 | static unsigned symbol_cost; | |
3355 | static unsigned address_cost; | |
7299dbfb ZD |
3356 | tree op0, op1; |
3357 | unsigned cost0, cost1, cost; | |
3358 | enum machine_mode mode; | |
8b11a64c ZD |
3359 | |
3360 | if (!costs_initialized) | |
3361 | { | |
3362 | tree var = create_tmp_var_raw (integer_type_node, "test_var"); | |
3363 | rtx x = gen_rtx_MEM (DECL_MODE (var), | |
3364 | gen_rtx_SYMBOL_REF (Pmode, "test_var")); | |
3365 | tree addr; | |
3366 | tree type = build_pointer_type (integer_type_node); | |
3367 | ||
3368 | integer_cost = computation_cost (build_int_cst_type (integer_type_node, | |
3369 | 2000)); | |
3370 | ||
3371 | SET_DECL_RTL (var, x); | |
3372 | TREE_STATIC (var) = 1; | |
3373 | addr = build1 (ADDR_EXPR, type, var); | |
3374 | symbol_cost = computation_cost (addr) + 1; | |
3375 | ||
3376 | address_cost | |
3377 | = computation_cost (build2 (PLUS_EXPR, type, | |
3378 | addr, | |
3379 | build_int_cst_type (type, 2000))) + 1; | |
3380 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3381 | { | |
3382 | fprintf (dump_file, "force_var_cost:\n"); | |
3383 | fprintf (dump_file, " integer %d\n", (int) integer_cost); | |
3384 | fprintf (dump_file, " symbol %d\n", (int) symbol_cost); | |
3385 | fprintf (dump_file, " address %d\n", (int) address_cost); | |
3386 | fprintf (dump_file, " other %d\n", (int) target_spill_cost); | |
3387 | fprintf (dump_file, "\n"); | |
3388 | } | |
3389 | ||
3390 | costs_initialized = true; | |
3391 | } | |
3392 | ||
f5e2738c ZD |
3393 | STRIP_NOPS (expr); |
3394 | ||
8b11a64c ZD |
3395 | if (depends_on) |
3396 | { | |
3397 | fd_ivopts_data = data; | |
3398 | walk_tree (&expr, find_depends, depends_on, NULL); | |
3399 | } | |
3400 | ||
3401 | if (SSA_VAR_P (expr)) | |
3402 | return 0; | |
3403 | ||
3404 | if (TREE_INVARIANT (expr)) | |
3405 | { | |
3406 | if (TREE_CODE (expr) == INTEGER_CST) | |
3407 | return integer_cost; | |
3408 | ||
3409 | if (TREE_CODE (expr) == ADDR_EXPR) | |
3410 | { | |
3411 | tree obj = TREE_OPERAND (expr, 0); | |
3412 | ||
3413 | if (TREE_CODE (obj) == VAR_DECL | |
3414 | || TREE_CODE (obj) == PARM_DECL | |
3415 | || TREE_CODE (obj) == RESULT_DECL) | |
3416 | return symbol_cost; | |
3417 | } | |
3418 | ||
3419 | return address_cost; | |
3420 | } | |
3421 | ||
7299dbfb ZD |
3422 | switch (TREE_CODE (expr)) |
3423 | { | |
3424 | case PLUS_EXPR: | |
3425 | case MINUS_EXPR: | |
3426 | case MULT_EXPR: | |
3427 | op0 = TREE_OPERAND (expr, 0); | |
3428 | op1 = TREE_OPERAND (expr, 1); | |
f5e2738c ZD |
3429 | STRIP_NOPS (op0); |
3430 | STRIP_NOPS (op1); | |
7299dbfb ZD |
3431 | |
3432 | if (is_gimple_val (op0)) | |
3433 | cost0 = 0; | |
3434 | else | |
3435 | cost0 = force_var_cost (data, op0, NULL); | |
3436 | ||
3437 | if (is_gimple_val (op1)) | |
3438 | cost1 = 0; | |
3439 | else | |
3440 | cost1 = force_var_cost (data, op1, NULL); | |
3441 | ||
3442 | break; | |
3443 | ||
3444 | default: | |
3445 | /* Just an arbitrary value, FIXME. */ | |
3446 | return target_spill_cost; | |
3447 | } | |
3448 | ||
3449 | mode = TYPE_MODE (TREE_TYPE (expr)); | |
3450 | switch (TREE_CODE (expr)) | |
3451 | { | |
3452 | case PLUS_EXPR: | |
3453 | case MINUS_EXPR: | |
3454 | cost = add_cost (mode); | |
3455 | break; | |
3456 | ||
3457 | case MULT_EXPR: | |
3458 | if (cst_and_fits_in_hwi (op0)) | |
3459 | cost = multiply_by_cost (int_cst_value (op0), mode); | |
3460 | else if (cst_and_fits_in_hwi (op1)) | |
3461 | cost = multiply_by_cost (int_cst_value (op1), mode); | |
3462 | else | |
3463 | return target_spill_cost; | |
3464 | break; | |
3465 | ||
3466 | default: | |
3467 | gcc_unreachable (); | |
3468 | } | |
3469 | ||
3470 | cost += cost0; | |
3471 | cost += cost1; | |
3472 | ||
3473 | /* Bound the cost by target_spill_cost. The parts of complicated | |
3474 | computations often are either loop invariant or at least can | |
3475 | be shared between several iv uses, so letting this grow without | |
3476 | limits would not give reasonable results. */ | |
3477 | return cost < target_spill_cost ? cost : target_spill_cost; | |
8b11a64c ZD |
3478 | } |
3479 | ||
8b11a64c ZD |
3480 | /* Estimates cost of expressing address ADDR as var + symbol + offset. The |
3481 | value of offset is added to OFFSET, SYMBOL_PRESENT and VAR_PRESENT are set | |
3482 | to false if the corresponding part is missing. DEPENDS_ON is a set of the | |
3483 | invariants the computation depends on. */ | |
3484 | ||
3485 | static unsigned | |
3486 | split_address_cost (struct ivopts_data *data, | |
3487 | tree addr, bool *symbol_present, bool *var_present, | |
3488 | unsigned HOST_WIDE_INT *offset, bitmap *depends_on) | |
3489 | { | |
2f4675b4 ZD |
3490 | tree core; |
3491 | HOST_WIDE_INT bitsize; | |
3492 | HOST_WIDE_INT bitpos; | |
3493 | tree toffset; | |
3494 | enum machine_mode mode; | |
3495 | int unsignedp, volatilep; | |
3496 | ||
3497 | core = get_inner_reference (addr, &bitsize, &bitpos, &toffset, &mode, | |
2614034e | 3498 | &unsignedp, &volatilep, false); |
8b11a64c | 3499 | |
2f4675b4 ZD |
3500 | if (toffset != 0 |
3501 | || bitpos % BITS_PER_UNIT != 0 | |
3502 | || TREE_CODE (core) != VAR_DECL) | |
8b11a64c ZD |
3503 | { |
3504 | *symbol_present = false; | |
3505 | *var_present = true; | |
3506 | fd_ivopts_data = data; | |
3507 | walk_tree (&addr, find_depends, depends_on, NULL); | |
3508 | return target_spill_cost; | |
2f4675b4 ZD |
3509 | } |
3510 | ||
3511 | *offset += bitpos / BITS_PER_UNIT; | |
8b11a64c ZD |
3512 | if (TREE_STATIC (core) |
3513 | || DECL_EXTERNAL (core)) | |
3514 | { | |
3515 | *symbol_present = true; | |
3516 | *var_present = false; | |
3517 | return 0; | |
3518 | } | |
3519 | ||
3520 | *symbol_present = false; | |
3521 | *var_present = true; | |
3522 | return 0; | |
3523 | } | |
3524 | ||
3525 | /* Estimates cost of expressing difference of addresses E1 - E2 as | |
3526 | var + symbol + offset. The value of offset is added to OFFSET, | |
3527 | SYMBOL_PRESENT and VAR_PRESENT are set to false if the corresponding | |
3528 | part is missing. DEPENDS_ON is a set of the invariants the computation | |
3529 | depends on. */ | |
3530 | ||
3531 | static unsigned | |
3532 | ptr_difference_cost (struct ivopts_data *data, | |
3533 | tree e1, tree e2, bool *symbol_present, bool *var_present, | |
3534 | unsigned HOST_WIDE_INT *offset, bitmap *depends_on) | |
3535 | { | |
2f4675b4 | 3536 | HOST_WIDE_INT diff = 0; |
8b11a64c ZD |
3537 | unsigned cost; |
3538 | ||
1e128c5f | 3539 | gcc_assert (TREE_CODE (e1) == ADDR_EXPR); |
8b11a64c | 3540 | |
7299dbfb | 3541 | if (ptr_difference_const (e1, e2, &diff)) |
8b11a64c ZD |
3542 | { |
3543 | *offset += diff; | |
3544 | *symbol_present = false; | |
3545 | *var_present = false; | |
3546 | return 0; | |
3547 | } | |
3548 | ||
3549 | if (e2 == integer_zero_node) | |
3550 | return split_address_cost (data, TREE_OPERAND (e1, 0), | |
3551 | symbol_present, var_present, offset, depends_on); | |
3552 | ||
3553 | *symbol_present = false; | |
3554 | *var_present = true; | |
3555 | ||
3556 | cost = force_var_cost (data, e1, depends_on); | |
3557 | cost += force_var_cost (data, e2, depends_on); | |
3558 | cost += add_cost (Pmode); | |
3559 | ||
3560 | return cost; | |
3561 | } | |
3562 | ||
3563 | /* Estimates cost of expressing difference E1 - E2 as | |
3564 | var + symbol + offset. The value of offset is added to OFFSET, | |
3565 | SYMBOL_PRESENT and VAR_PRESENT are set to false if the corresponding | |
3566 | part is missing. DEPENDS_ON is a set of the invariants the computation | |
3567 | depends on. */ | |
3568 | ||
3569 | static unsigned | |
3570 | difference_cost (struct ivopts_data *data, | |
3571 | tree e1, tree e2, bool *symbol_present, bool *var_present, | |
3572 | unsigned HOST_WIDE_INT *offset, bitmap *depends_on) | |
3573 | { | |
3574 | unsigned cost; | |
3575 | enum machine_mode mode = TYPE_MODE (TREE_TYPE (e1)); | |
f5e2738c ZD |
3576 | unsigned HOST_WIDE_INT off1, off2; |
3577 | ||
9be872b7 ZD |
3578 | e1 = strip_offset (e1, &off1); |
3579 | e2 = strip_offset (e2, &off2); | |
f5e2738c | 3580 | *offset += off1 - off2; |
8b11a64c | 3581 | |
f5e2738c ZD |
3582 | STRIP_NOPS (e1); |
3583 | STRIP_NOPS (e2); | |
8b11a64c ZD |
3584 | |
3585 | if (TREE_CODE (e1) == ADDR_EXPR) | |
3586 | return ptr_difference_cost (data, e1, e2, symbol_present, var_present, offset, | |
3587 | depends_on); | |
3588 | *symbol_present = false; | |
3589 | ||
3590 | if (operand_equal_p (e1, e2, 0)) | |
3591 | { | |
3592 | *var_present = false; | |
3593 | return 0; | |
3594 | } | |
3595 | *var_present = true; | |
3596 | if (zero_p (e2)) | |
3597 | return force_var_cost (data, e1, depends_on); | |
3598 | ||
3599 | if (zero_p (e1)) | |
3600 | { | |
3601 | cost = force_var_cost (data, e2, depends_on); | |
3602 | cost += multiply_by_cost (-1, mode); | |
3603 | ||
3604 | return cost; | |
3605 | } | |
3606 | ||
3607 | cost = force_var_cost (data, e1, depends_on); | |
3608 | cost += force_var_cost (data, e2, depends_on); | |
3609 | cost += add_cost (mode); | |
3610 | ||
3611 | return cost; | |
3612 | } | |
3613 | ||
3614 | /* Determines the cost of the computation by that USE is expressed | |
3615 | from induction variable CAND. If ADDRESS_P is true, we just need | |
3616 | to create an address from it, otherwise we want to get it into | |
3617 | register. A set of invariants we depend on is stored in | |
3618 | DEPENDS_ON. AT is the statement at that the value is computed. */ | |
3619 | ||
3620 | static unsigned | |
3621 | get_computation_cost_at (struct ivopts_data *data, | |
3622 | struct iv_use *use, struct iv_cand *cand, | |
3623 | bool address_p, bitmap *depends_on, tree at) | |
3624 | { | |
3625 | tree ubase = use->iv->base, ustep = use->iv->step; | |
3626 | tree cbase, cstep; | |
3627 | tree utype = TREE_TYPE (ubase), ctype; | |
3628 | unsigned HOST_WIDE_INT ustepi, cstepi, offset = 0; | |
3629 | HOST_WIDE_INT ratio, aratio; | |
3630 | bool var_present, symbol_present; | |
3631 | unsigned cost = 0, n_sums; | |
3632 | ||
3633 | *depends_on = NULL; | |
3634 | ||
3635 | /* Only consider real candidates. */ | |
3636 | if (!cand->iv) | |
3637 | return INFTY; | |
3638 | ||
3639 | cbase = cand->iv->base; | |
3640 | cstep = cand->iv->step; | |
3641 | ctype = TREE_TYPE (cbase); | |
3642 | ||
3643 | if (TYPE_PRECISION (utype) > TYPE_PRECISION (ctype)) | |
3644 | { | |
3645 | /* We do not have a precision to express the values of use. */ | |
3646 | return INFTY; | |
3647 | } | |
3648 | ||
e6845c23 ZD |
3649 | if (address_p) |
3650 | { | |
3651 | /* Do not try to express address of an object with computation based | |
3652 | on address of a different object. This may cause problems in rtl | |
3653 | level alias analysis (that does not expect this to be happening, | |
3654 | as this is illegal in C), and would be unlikely to be useful | |
3655 | anyway. */ | |
3656 | if (use->iv->base_object | |
3657 | && cand->iv->base_object | |
3658 | && !operand_equal_p (use->iv->base_object, cand->iv->base_object, 0)) | |
3659 | return INFTY; | |
3660 | } | |
3661 | ||
8b11a64c ZD |
3662 | if (TYPE_PRECISION (utype) != TYPE_PRECISION (ctype)) |
3663 | { | |
3664 | /* TODO -- add direct handling of this case. */ | |
3665 | goto fallback; | |
3666 | } | |
3667 | ||
9be872b7 ZD |
3668 | /* CSTEPI is removed from the offset in case statement is after the |
3669 | increment. If the step is not constant, we use zero instead. | |
1e1def1c | 3670 | This is a bit imprecise (there is the extra addition), but |
9be872b7 ZD |
3671 | redundancy elimination is likely to transform the code so that |
3672 | it uses value of the variable before increment anyway, | |
3673 | so it is not that much unrealistic. */ | |
3674 | if (cst_and_fits_in_hwi (cstep)) | |
3675 | cstepi = int_cst_value (cstep); | |
3676 | else | |
3677 | cstepi = 0; | |
3678 | ||
3679 | if (cst_and_fits_in_hwi (ustep) | |
3680 | && cst_and_fits_in_hwi (cstep)) | |
3681 | { | |
3682 | ustepi = int_cst_value (ustep); | |
3683 | ||
3684 | if (!divide (TYPE_PRECISION (utype), ustepi, cstepi, &ratio)) | |
3685 | return INFTY; | |
3686 | } | |
3687 | else | |
3688 | { | |
3689 | tree rat; | |
3690 | ||
3691 | rat = constant_multiple_of (utype, ustep, cstep); | |
3692 | ||
3693 | if (!rat) | |
3694 | return INFTY; | |
3695 | ||
3696 | if (cst_and_fits_in_hwi (rat)) | |
3697 | ratio = int_cst_value (rat); | |
3698 | else if (integer_onep (rat)) | |
3699 | ratio = 1; | |
3700 | else if (integer_all_onesp (rat)) | |
3701 | ratio = -1; | |
3702 | else | |
3703 | return INFTY; | |
3704 | } | |
8b11a64c ZD |
3705 | |
3706 | /* use = ubase + ratio * (var - cbase). If either cbase is a constant | |
3707 | or ratio == 1, it is better to handle this like | |
3708 | ||
3709 | ubase - ratio * cbase + ratio * var | |
3710 | ||
3711 | (also holds in the case ratio == -1, TODO. */ | |
3712 | ||
9be872b7 | 3713 | if (cst_and_fits_in_hwi (cbase)) |
8b11a64c ZD |
3714 | { |
3715 | offset = - ratio * int_cst_value (cbase); | |
3716 | cost += difference_cost (data, | |
3717 | ubase, integer_zero_node, | |
3718 | &symbol_present, &var_present, &offset, | |
3719 | depends_on); | |
3720 | } | |
3721 | else if (ratio == 1) | |
3722 | { | |
3723 | cost += difference_cost (data, | |
3724 | ubase, cbase, | |
3725 | &symbol_present, &var_present, &offset, | |
3726 | depends_on); | |
3727 | } | |
3728 | else | |
3729 | { | |
3730 | cost += force_var_cost (data, cbase, depends_on); | |
3731 | cost += add_cost (TYPE_MODE (ctype)); | |
3732 | cost += difference_cost (data, | |
3733 | ubase, integer_zero_node, | |
3734 | &symbol_present, &var_present, &offset, | |
3735 | depends_on); | |
3736 | } | |
3737 | ||
3738 | /* If we are after the increment, the value of the candidate is higher by | |
3739 | one iteration. */ | |
3740 | if (stmt_after_increment (data->current_loop, cand, at)) | |
3741 | offset -= ratio * cstepi; | |
3742 | ||
3743 | /* Now the computation is in shape symbol + var1 + const + ratio * var2. | |
3744 | (symbol/var/const parts may be omitted). If we are looking for an address, | |
3745 | find the cost of addressing this. */ | |
3746 | if (address_p) | |
7299dbfb | 3747 | return cost + get_address_cost (symbol_present, var_present, offset, ratio); |
8b11a64c ZD |
3748 | |
3749 | /* Otherwise estimate the costs for computing the expression. */ | |
3750 | aratio = ratio > 0 ? ratio : -ratio; | |
3751 | if (!symbol_present && !var_present && !offset) | |
3752 | { | |
3753 | if (ratio != 1) | |
3754 | cost += multiply_by_cost (ratio, TYPE_MODE (ctype)); | |
3755 | ||
3756 | return cost; | |
3757 | } | |
3758 | ||
3759 | if (aratio != 1) | |
3760 | cost += multiply_by_cost (aratio, TYPE_MODE (ctype)); | |
3761 | ||
3762 | n_sums = 1; | |
3763 | if (var_present | |
3764 | /* Symbol + offset should be compile-time computable. */ | |
3765 | && (symbol_present || offset)) | |
3766 | n_sums++; | |
3767 | ||
3768 | return cost + n_sums * add_cost (TYPE_MODE (ctype)); | |
3769 | ||
3770 | fallback: | |
3771 | { | |
3772 | /* Just get the expression, expand it and measure the cost. */ | |
3773 | tree comp = get_computation_at (data->current_loop, use, cand, at); | |
3774 | ||
3775 | if (!comp) | |
3776 | return INFTY; | |
3777 | ||
3778 | if (address_p) | |
3779 | comp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (comp)), comp); | |
3780 | ||
3781 | return computation_cost (comp); | |
3782 | } | |
3783 | } | |
3784 | ||
3785 | /* Determines the cost of the computation by that USE is expressed | |
3786 | from induction variable CAND. If ADDRESS_P is true, we just need | |
3787 | to create an address from it, otherwise we want to get it into | |
3788 | register. A set of invariants we depend on is stored in | |
3789 | DEPENDS_ON. */ | |
3790 | ||
3791 | static unsigned | |
3792 | get_computation_cost (struct ivopts_data *data, | |
3793 | struct iv_use *use, struct iv_cand *cand, | |
3794 | bool address_p, bitmap *depends_on) | |
3795 | { | |
3796 | return get_computation_cost_at (data, | |
3797 | use, cand, address_p, depends_on, use->stmt); | |
3798 | } | |
3799 | ||
3800 | /* Determines cost of basing replacement of USE on CAND in a generic | |
3801 | expression. */ | |
3802 | ||
b1b02be2 | 3803 | static bool |
8b11a64c ZD |
3804 | determine_use_iv_cost_generic (struct ivopts_data *data, |
3805 | struct iv_use *use, struct iv_cand *cand) | |
3806 | { | |
3807 | bitmap depends_on; | |
eec5fec9 ZD |
3808 | unsigned cost; |
3809 | ||
3810 | /* The simple case first -- if we need to express value of the preserved | |
3811 | original biv, the cost is 0. This also prevents us from counting the | |
3812 | cost of increment twice -- once at this use and once in the cost of | |
3813 | the candidate. */ | |
3814 | if (cand->pos == IP_ORIGINAL | |
3815 | && cand->incremented_at == use->stmt) | |
3816 | { | |
f5f12961 | 3817 | set_use_iv_cost (data, use, cand, 0, NULL, NULL_TREE); |
eec5fec9 ZD |
3818 | return true; |
3819 | } | |
8b11a64c | 3820 | |
eec5fec9 | 3821 | cost = get_computation_cost (data, use, cand, false, &depends_on); |
f5f12961 | 3822 | set_use_iv_cost (data, use, cand, cost, depends_on, NULL_TREE); |
b1b02be2 ZD |
3823 | |
3824 | return cost != INFTY; | |
8b11a64c ZD |
3825 | } |
3826 | ||
3827 | /* Determines cost of basing replacement of USE on CAND in an address. */ | |
3828 | ||
b1b02be2 | 3829 | static bool |
8b11a64c ZD |
3830 | determine_use_iv_cost_address (struct ivopts_data *data, |
3831 | struct iv_use *use, struct iv_cand *cand) | |
3832 | { | |
3833 | bitmap depends_on; | |
3834 | unsigned cost = get_computation_cost (data, use, cand, true, &depends_on); | |
3835 | ||
f5f12961 | 3836 | set_use_iv_cost (data, use, cand, cost, depends_on, NULL_TREE); |
b1b02be2 ZD |
3837 | |
3838 | return cost != INFTY; | |
8b11a64c ZD |
3839 | } |
3840 | ||
3841 | /* Computes value of induction variable IV in iteration NITER. */ | |
3842 | ||
3843 | static tree | |
3844 | iv_value (struct iv *iv, tree niter) | |
3845 | { | |
3846 | tree val; | |
3847 | tree type = TREE_TYPE (iv->base); | |
3848 | ||
3849 | niter = fold_convert (type, niter); | |
2f4675b4 | 3850 | val = fold (build2 (MULT_EXPR, type, iv->step, niter)); |
8b11a64c ZD |
3851 | |
3852 | return fold (build2 (PLUS_EXPR, type, iv->base, val)); | |
3853 | } | |
3854 | ||
3855 | /* Computes value of candidate CAND at position AT in iteration NITER. */ | |
3856 | ||
3857 | static tree | |
3858 | cand_value_at (struct loop *loop, struct iv_cand *cand, tree at, tree niter) | |
3859 | { | |
3860 | tree val = iv_value (cand->iv, niter); | |
3861 | tree type = TREE_TYPE (cand->iv->base); | |
3862 | ||
3863 | if (stmt_after_increment (loop, cand, at)) | |
3864 | val = fold (build2 (PLUS_EXPR, type, val, cand->iv->step)); | |
3865 | ||
3866 | return val; | |
3867 | } | |
3868 | ||
ca4c3169 ZD |
3869 | /* Returns period of induction variable iv. */ |
3870 | ||
3871 | static tree | |
3872 | iv_period (struct iv *iv) | |
3873 | { | |
3874 | tree step = iv->step, period, type; | |
3875 | tree pow2div; | |
3876 | ||
3877 | gcc_assert (step && TREE_CODE (step) == INTEGER_CST); | |
3878 | ||
3879 | /* Period of the iv is gcd (step, type range). Since type range is power | |
3880 | of two, it suffices to determine the maximum power of two that divides | |
3881 | step. */ | |
3882 | pow2div = num_ending_zeros (step); | |
3883 | type = unsigned_type_for (TREE_TYPE (step)); | |
3884 | ||
3885 | period = build_low_bits_mask (type, | |
3886 | (TYPE_PRECISION (type) | |
3887 | - tree_low_cst (pow2div, 1))); | |
3888 | ||
3889 | return period; | |
3890 | } | |
3891 | ||
f5f12961 ZD |
3892 | /* Returns the comparison operator used when eliminating the iv USE. */ |
3893 | ||
3894 | static enum tree_code | |
3895 | iv_elimination_compare (struct ivopts_data *data, struct iv_use *use) | |
3896 | { | |
3897 | struct loop *loop = data->current_loop; | |
3898 | basic_block ex_bb; | |
3899 | edge exit; | |
3900 | ||
3901 | ex_bb = bb_for_stmt (use->stmt); | |
3902 | exit = EDGE_SUCC (ex_bb, 0); | |
3903 | if (flow_bb_inside_loop_p (loop, exit->dest)) | |
3904 | exit = EDGE_SUCC (ex_bb, 1); | |
3905 | ||
3906 | return (exit->flags & EDGE_TRUE_VALUE ? EQ_EXPR : NE_EXPR); | |
3907 | } | |
3908 | ||
8b11a64c | 3909 | /* Check whether it is possible to express the condition in USE by comparison |
f5f12961 | 3910 | of candidate CAND. If so, store the value compared with to BOUND. */ |
8b11a64c ZD |
3911 | |
3912 | static bool | |
ca4c3169 | 3913 | may_eliminate_iv (struct ivopts_data *data, |
f5f12961 | 3914 | struct iv_use *use, struct iv_cand *cand, tree *bound) |
8b11a64c | 3915 | { |
e6845c23 | 3916 | basic_block ex_bb; |
8b11a64c | 3917 | edge exit; |
ca4c3169 ZD |
3918 | struct tree_niter_desc *niter; |
3919 | tree nit, nit_type; | |
3920 | tree wider_type, period, per_type; | |
3921 | struct loop *loop = data->current_loop; | |
e6845c23 | 3922 | |
9be872b7 ZD |
3923 | if (TREE_CODE (cand->iv->step) != INTEGER_CST) |
3924 | return false; | |
3925 | ||
e6845c23 ZD |
3926 | /* For now works only for exits that dominate the loop latch. TODO -- extend |
3927 | for other conditions inside loop body. */ | |
3928 | ex_bb = bb_for_stmt (use->stmt); | |
3929 | if (use->stmt != last_stmt (ex_bb) | |
3930 | || TREE_CODE (use->stmt) != COND_EXPR) | |
8b11a64c | 3931 | return false; |
e6845c23 | 3932 | if (!dominated_by_p (CDI_DOMINATORS, loop->latch, ex_bb)) |
8b11a64c ZD |
3933 | return false; |
3934 | ||
e6845c23 ZD |
3935 | exit = EDGE_SUCC (ex_bb, 0); |
3936 | if (flow_bb_inside_loop_p (loop, exit->dest)) | |
3937 | exit = EDGE_SUCC (ex_bb, 1); | |
3938 | if (flow_bb_inside_loop_p (loop, exit->dest)) | |
3939 | return false; | |
3940 | ||
ca4c3169 ZD |
3941 | niter = niter_for_exit (data, exit); |
3942 | if (!niter | |
3943 | || !zero_p (niter->may_be_zero)) | |
8b11a64c ZD |
3944 | return false; |
3945 | ||
ca4c3169 ZD |
3946 | nit = niter->niter; |
3947 | nit_type = TREE_TYPE (nit); | |
8b11a64c | 3948 | |
ca4c3169 ZD |
3949 | /* Determine whether we may use the variable to test whether niter iterations |
3950 | elapsed. This is the case iff the period of the induction variable is | |
3951 | greater than the number of iterations. */ | |
3952 | period = iv_period (cand->iv); | |
3953 | if (!period) | |
8b11a64c | 3954 | return false; |
ca4c3169 ZD |
3955 | per_type = TREE_TYPE (period); |
3956 | ||
3957 | wider_type = TREE_TYPE (period); | |
3958 | if (TYPE_PRECISION (nit_type) < TYPE_PRECISION (per_type)) | |
3959 | wider_type = per_type; | |
3960 | else | |
3961 | wider_type = nit_type; | |
8b11a64c | 3962 | |
ca4c3169 ZD |
3963 | if (!integer_nonzerop (fold (build2 (GE_EXPR, boolean_type_node, |
3964 | fold_convert (wider_type, period), | |
3965 | fold_convert (wider_type, nit))))) | |
8b11a64c ZD |
3966 | return false; |
3967 | ||
ca4c3169 | 3968 | *bound = cand_value_at (loop, cand, use->stmt, nit); |
8b11a64c ZD |
3969 | return true; |
3970 | } | |
3971 | ||
3972 | /* Determines cost of basing replacement of USE on CAND in a condition. */ | |
3973 | ||
b1b02be2 | 3974 | static bool |
8b11a64c ZD |
3975 | determine_use_iv_cost_condition (struct ivopts_data *data, |
3976 | struct iv_use *use, struct iv_cand *cand) | |
3977 | { | |
f5f12961 ZD |
3978 | tree bound = NULL_TREE, op, cond; |
3979 | bitmap depends_on = NULL; | |
3980 | unsigned cost; | |
8b11a64c ZD |
3981 | |
3982 | /* Only consider real candidates. */ | |
3983 | if (!cand->iv) | |
3984 | { | |
f5f12961 | 3985 | set_use_iv_cost (data, use, cand, INFTY, NULL, NULL_TREE); |
b1b02be2 | 3986 | return false; |
8b11a64c ZD |
3987 | } |
3988 | ||
f5f12961 | 3989 | if (may_eliminate_iv (data, use, cand, &bound)) |
8b11a64c | 3990 | { |
f5f12961 | 3991 | cost = force_var_cost (data, bound, &depends_on); |
8b11a64c | 3992 | |
f5f12961 | 3993 | set_use_iv_cost (data, use, cand, cost, depends_on, bound); |
b1b02be2 | 3994 | return cost != INFTY; |
8b11a64c ZD |
3995 | } |
3996 | ||
3997 | /* The induction variable elimination failed; just express the original | |
3998 | giv. If it is compared with an invariant, note that we cannot get | |
3999 | rid of it. */ | |
f5f12961 ZD |
4000 | cost = get_computation_cost (data, use, cand, false, &depends_on); |
4001 | ||
4002 | cond = *use->op_p; | |
4003 | if (TREE_CODE (cond) != SSA_NAME) | |
8b11a64c | 4004 | { |
f5f12961 ZD |
4005 | op = TREE_OPERAND (cond, 0); |
4006 | if (TREE_CODE (op) == SSA_NAME && !zero_p (get_iv (data, op)->step)) | |
4007 | op = TREE_OPERAND (cond, 1); | |
4008 | if (TREE_CODE (op) == SSA_NAME) | |
4009 | { | |
4010 | op = get_iv (data, op)->base; | |
4011 | fd_ivopts_data = data; | |
4012 | walk_tree (&op, find_depends, &depends_on, NULL); | |
4013 | } | |
8b11a64c ZD |
4014 | } |
4015 | ||
f5f12961 ZD |
4016 | set_use_iv_cost (data, use, cand, cost, depends_on, NULL); |
4017 | return cost != INFTY; | |
8b11a64c ZD |
4018 | } |
4019 | ||
4020 | /* Checks whether it is possible to replace the final value of USE by | |
4021 | a direct computation. If so, the formula is stored to *VALUE. */ | |
4022 | ||
4023 | static bool | |
ca4c3169 ZD |
4024 | may_replace_final_value (struct ivopts_data *data, struct iv_use *use, |
4025 | tree *value) | |
8b11a64c | 4026 | { |
ca4c3169 | 4027 | struct loop *loop = data->current_loop; |
8b11a64c ZD |
4028 | edge exit; |
4029 | struct tree_niter_desc *niter; | |
4030 | ||
4031 | exit = single_dom_exit (loop); | |
4032 | if (!exit) | |
4033 | return false; | |
4034 | ||
1e128c5f GB |
4035 | gcc_assert (dominated_by_p (CDI_DOMINATORS, exit->src, |
4036 | bb_for_stmt (use->stmt))); | |
8b11a64c | 4037 | |
ca4c3169 ZD |
4038 | niter = niter_for_single_dom_exit (data); |
4039 | if (!niter | |
4040 | || !zero_p (niter->may_be_zero)) | |
8b11a64c ZD |
4041 | return false; |
4042 | ||
4043 | *value = iv_value (use->iv, niter->niter); | |
4044 | ||
4045 | return true; | |
4046 | } | |
4047 | ||
4048 | /* Determines cost of replacing final value of USE using CAND. */ | |
4049 | ||
b1b02be2 | 4050 | static bool |
8b11a64c ZD |
4051 | determine_use_iv_cost_outer (struct ivopts_data *data, |
4052 | struct iv_use *use, struct iv_cand *cand) | |
4053 | { | |
4054 | bitmap depends_on; | |
4055 | unsigned cost; | |
4056 | edge exit; | |
f5f12961 | 4057 | tree value = NULL_TREE; |
8b11a64c | 4058 | struct loop *loop = data->current_loop; |
eec5fec9 ZD |
4059 | |
4060 | /* The simple case first -- if we need to express value of the preserved | |
4061 | original biv, the cost is 0. This also prevents us from counting the | |
4062 | cost of increment twice -- once at this use and once in the cost of | |
4063 | the candidate. */ | |
4064 | if (cand->pos == IP_ORIGINAL | |
4065 | && cand->incremented_at == use->stmt) | |
4066 | { | |
f5f12961 | 4067 | set_use_iv_cost (data, use, cand, 0, NULL, NULL_TREE); |
eec5fec9 ZD |
4068 | return true; |
4069 | } | |
4070 | ||
8b11a64c ZD |
4071 | if (!cand->iv) |
4072 | { | |
ca4c3169 | 4073 | if (!may_replace_final_value (data, use, &value)) |
8b11a64c | 4074 | { |
f5f12961 | 4075 | set_use_iv_cost (data, use, cand, INFTY, NULL, NULL_TREE); |
b1b02be2 | 4076 | return false; |
8b11a64c ZD |
4077 | } |
4078 | ||
4079 | depends_on = NULL; | |
4080 | cost = force_var_cost (data, value, &depends_on); | |
4081 | ||
4082 | cost /= AVG_LOOP_NITER (loop); | |
4083 | ||
f5f12961 | 4084 | set_use_iv_cost (data, use, cand, cost, depends_on, value); |
b1b02be2 | 4085 | return cost != INFTY; |
8b11a64c ZD |
4086 | } |
4087 | ||
4088 | exit = single_dom_exit (loop); | |
4089 | if (exit) | |
4090 | { | |
4091 | /* If there is just a single exit, we may use value of the candidate | |
4092 | after we take it to determine the value of use. */ | |
4093 | cost = get_computation_cost_at (data, use, cand, false, &depends_on, | |
4094 | last_stmt (exit->src)); | |
4095 | if (cost != INFTY) | |
4096 | cost /= AVG_LOOP_NITER (loop); | |
4097 | } | |
4098 | else | |
4099 | { | |
4100 | /* Otherwise we just need to compute the iv. */ | |
4101 | cost = get_computation_cost (data, use, cand, false, &depends_on); | |
4102 | } | |
4103 | ||
f5f12961 | 4104 | set_use_iv_cost (data, use, cand, cost, depends_on, NULL_TREE); |
b1b02be2 ZD |
4105 | |
4106 | return cost != INFTY; | |
8b11a64c ZD |
4107 | } |
4108 | ||
b1b02be2 ZD |
4109 | /* Determines cost of basing replacement of USE on CAND. Returns false |
4110 | if USE cannot be based on CAND. */ | |
8b11a64c | 4111 | |
b1b02be2 | 4112 | static bool |
8b11a64c ZD |
4113 | determine_use_iv_cost (struct ivopts_data *data, |
4114 | struct iv_use *use, struct iv_cand *cand) | |
4115 | { | |
4116 | switch (use->type) | |
4117 | { | |
4118 | case USE_NONLINEAR_EXPR: | |
b1b02be2 | 4119 | return determine_use_iv_cost_generic (data, use, cand); |
8b11a64c ZD |
4120 | |
4121 | case USE_OUTER: | |
b1b02be2 | 4122 | return determine_use_iv_cost_outer (data, use, cand); |
8b11a64c ZD |
4123 | |
4124 | case USE_ADDRESS: | |
b1b02be2 | 4125 | return determine_use_iv_cost_address (data, use, cand); |
8b11a64c ZD |
4126 | |
4127 | case USE_COMPARE: | |
b1b02be2 | 4128 | return determine_use_iv_cost_condition (data, use, cand); |
8b11a64c ZD |
4129 | |
4130 | default: | |
1e128c5f | 4131 | gcc_unreachable (); |
8b11a64c ZD |
4132 | } |
4133 | } | |
4134 | ||
4135 | /* Determines costs of basing the use of the iv on an iv candidate. */ | |
4136 | ||
4137 | static void | |
4138 | determine_use_iv_costs (struct ivopts_data *data) | |
4139 | { | |
4140 | unsigned i, j; | |
4141 | struct iv_use *use; | |
4142 | struct iv_cand *cand; | |
8bdbfff5 | 4143 | bitmap to_clear = BITMAP_ALLOC (NULL); |
8b11a64c ZD |
4144 | |
4145 | alloc_use_cost_map (data); | |
4146 | ||
8b11a64c ZD |
4147 | for (i = 0; i < n_iv_uses (data); i++) |
4148 | { | |
4149 | use = iv_use (data, i); | |
4150 | ||
4151 | if (data->consider_all_candidates) | |
4152 | { | |
4153 | for (j = 0; j < n_iv_cands (data); j++) | |
4154 | { | |
4155 | cand = iv_cand (data, j); | |
4156 | determine_use_iv_cost (data, use, cand); | |
4157 | } | |
4158 | } | |
4159 | else | |
4160 | { | |
87c476a2 ZD |
4161 | bitmap_iterator bi; |
4162 | ||
4163 | EXECUTE_IF_SET_IN_BITMAP (use->related_cands, 0, j, bi) | |
8b11a64c ZD |
4164 | { |
4165 | cand = iv_cand (data, j); | |
b1b02be2 ZD |
4166 | if (!determine_use_iv_cost (data, use, cand)) |
4167 | bitmap_set_bit (to_clear, j); | |
87c476a2 | 4168 | } |
b1b02be2 ZD |
4169 | |
4170 | /* Remove the candidates for that the cost is infinite from | |
4171 | the list of related candidates. */ | |
4172 | bitmap_and_compl_into (use->related_cands, to_clear); | |
4173 | bitmap_clear (to_clear); | |
8b11a64c ZD |
4174 | } |
4175 | } | |
4176 | ||
8bdbfff5 | 4177 | BITMAP_FREE (to_clear); |
b1b02be2 | 4178 | |
8b11a64c ZD |
4179 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4180 | { | |
4181 | fprintf (dump_file, "Use-candidate costs:\n"); | |
4182 | ||
4183 | for (i = 0; i < n_iv_uses (data); i++) | |
4184 | { | |
4185 | use = iv_use (data, i); | |
4186 | ||
4187 | fprintf (dump_file, "Use %d:\n", i); | |
4188 | fprintf (dump_file, " cand\tcost\tdepends on\n"); | |
4189 | for (j = 0; j < use->n_map_members; j++) | |
4190 | { | |
4191 | if (!use->cost_map[j].cand | |
4192 | || use->cost_map[j].cost == INFTY) | |
4193 | continue; | |
4194 | ||
4195 | fprintf (dump_file, " %d\t%d\t", | |
4196 | use->cost_map[j].cand->id, | |
4197 | use->cost_map[j].cost); | |
4198 | if (use->cost_map[j].depends_on) | |
4199 | bitmap_print (dump_file, | |
4200 | use->cost_map[j].depends_on, "",""); | |
4201 | fprintf (dump_file, "\n"); | |
4202 | } | |
4203 | ||
4204 | fprintf (dump_file, "\n"); | |
4205 | } | |
4206 | fprintf (dump_file, "\n"); | |
4207 | } | |
4208 | } | |
4209 | ||
4210 | /* Determines cost of the candidate CAND. */ | |
4211 | ||
4212 | static void | |
4213 | determine_iv_cost (struct ivopts_data *data, struct iv_cand *cand) | |
4214 | { | |
4215 | unsigned cost_base, cost_step; | |
4366cf6d | 4216 | tree base; |
8b11a64c ZD |
4217 | |
4218 | if (!cand->iv) | |
4219 | { | |
4220 | cand->cost = 0; | |
4221 | return; | |
4222 | } | |
4223 | ||
4224 | /* There are two costs associated with the candidate -- its increment | |
4225 | and its initialization. The second is almost negligible for any loop | |
4226 | that rolls enough, so we take it just very little into account. */ | |
4227 | ||
4228 | base = cand->iv->base; | |
4229 | cost_base = force_var_cost (data, base, NULL); | |
4230 | cost_step = add_cost (TYPE_MODE (TREE_TYPE (base))); | |
4231 | ||
4232 | cand->cost = cost_step + cost_base / AVG_LOOP_NITER (current_loop); | |
4233 | ||
cf5d1802 ZD |
4234 | /* Prefer the original iv unless we may gain something by replacing it; |
4235 | this is not really relevant for artificial ivs created by other | |
4236 | passes. */ | |
4237 | if (cand->pos == IP_ORIGINAL | |
4238 | && !DECL_ARTIFICIAL (SSA_NAME_VAR (cand->var_before))) | |
8b11a64c ZD |
4239 | cand->cost--; |
4240 | ||
4241 | /* Prefer not to insert statements into latch unless there are some | |
4242 | already (so that we do not create unnecessary jumps). */ | |
4366cf6d ZD |
4243 | if (cand->pos == IP_END |
4244 | && empty_block_p (ip_end_pos (data->current_loop))) | |
4245 | cand->cost++; | |
8b11a64c ZD |
4246 | } |
4247 | ||
4248 | /* Determines costs of computation of the candidates. */ | |
4249 | ||
4250 | static void | |
4251 | determine_iv_costs (struct ivopts_data *data) | |
4252 | { | |
4253 | unsigned i; | |
4254 | ||
4255 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4256 | { | |
4257 | fprintf (dump_file, "Candidate costs:\n"); | |
4258 | fprintf (dump_file, " cand\tcost\n"); | |
4259 | } | |
4260 | ||
4261 | for (i = 0; i < n_iv_cands (data); i++) | |
4262 | { | |
4263 | struct iv_cand *cand = iv_cand (data, i); | |
4264 | ||
4265 | determine_iv_cost (data, cand); | |
4266 | ||
4267 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4268 | fprintf (dump_file, " %d\t%d\n", i, cand->cost); | |
4269 | } | |
4270 | ||
4271 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4272 | fprintf (dump_file, "\n"); | |
4273 | } | |
4274 | ||
4275 | /* Calculates cost for having SIZE induction variables. */ | |
4276 | ||
4277 | static unsigned | |
4278 | ivopts_global_cost_for_size (struct ivopts_data *data, unsigned size) | |
4279 | { | |
4280 | return global_cost_for_size (size, | |
4281 | loop_data (data->current_loop)->regs_used, | |
4282 | n_iv_uses (data)); | |
4283 | } | |
4284 | ||
4285 | /* For each size of the induction variable set determine the penalty. */ | |
4286 | ||
4287 | static void | |
4288 | determine_set_costs (struct ivopts_data *data) | |
4289 | { | |
4290 | unsigned j, n; | |
4291 | tree phi, op; | |
4292 | struct loop *loop = data->current_loop; | |
87c476a2 | 4293 | bitmap_iterator bi; |
8b11a64c ZD |
4294 | |
4295 | /* We use the following model (definitely improvable, especially the | |
4296 | cost function -- TODO): | |
4297 | ||
4298 | We estimate the number of registers available (using MD data), name it A. | |
4299 | ||
4300 | We estimate the number of registers used by the loop, name it U. This | |
4301 | number is obtained as the number of loop phi nodes (not counting virtual | |
4302 | registers and bivs) + the number of variables from outside of the loop. | |
4303 | ||
4304 | We set a reserve R (free regs that are used for temporary computations, | |
4305 | etc.). For now the reserve is a constant 3. | |
4306 | ||
4307 | Let I be the number of induction variables. | |
4308 | ||
4309 | -- if U + I + R <= A, the cost is I * SMALL_COST (just not to encourage | |
4310 | make a lot of ivs without a reason). | |
4311 | -- if A - R < U + I <= A, the cost is I * PRES_COST | |
4312 | -- if U + I > A, the cost is I * PRES_COST and | |
4313 | number of uses * SPILL_COST * (U + I - A) / (U + I) is added. */ | |
4314 | ||
4315 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4316 | { | |
4317 | fprintf (dump_file, "Global costs:\n"); | |
4318 | fprintf (dump_file, " target_avail_regs %d\n", target_avail_regs); | |
4319 | fprintf (dump_file, " target_small_cost %d\n", target_small_cost); | |
4320 | fprintf (dump_file, " target_pres_cost %d\n", target_pres_cost); | |
4321 | fprintf (dump_file, " target_spill_cost %d\n", target_spill_cost); | |
4322 | } | |
4323 | ||
4324 | n = 0; | |
bb29d951 | 4325 | for (phi = phi_nodes (loop->header); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
4326 | { |
4327 | op = PHI_RESULT (phi); | |
4328 | ||
4329 | if (!is_gimple_reg (op)) | |
4330 | continue; | |
4331 | ||
4332 | if (get_iv (data, op)) | |
4333 | continue; | |
4334 | ||
4335 | n++; | |
4336 | } | |
4337 | ||
87c476a2 | 4338 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, j, bi) |
8b11a64c ZD |
4339 | { |
4340 | struct version_info *info = ver_info (data, j); | |
4341 | ||
4342 | if (info->inv_id && info->has_nonlin_use) | |
4343 | n++; | |
87c476a2 | 4344 | } |
8b11a64c ZD |
4345 | |
4346 | loop_data (loop)->regs_used = n; | |
4347 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4348 | fprintf (dump_file, " regs_used %d\n", n); | |
4349 | ||
4350 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4351 | { | |
4352 | fprintf (dump_file, " cost for size:\n"); | |
4353 | fprintf (dump_file, " ivs\tcost\n"); | |
4354 | for (j = 0; j <= 2 * target_avail_regs; j++) | |
4355 | fprintf (dump_file, " %d\t%d\n", j, | |
4356 | ivopts_global_cost_for_size (data, j)); | |
4357 | fprintf (dump_file, "\n"); | |
4358 | } | |
4359 | } | |
4360 | ||
b1b02be2 | 4361 | /* Returns true if A is a cheaper cost pair than B. */ |
8b11a64c | 4362 | |
b1b02be2 ZD |
4363 | static bool |
4364 | cheaper_cost_pair (struct cost_pair *a, struct cost_pair *b) | |
8b11a64c | 4365 | { |
b1b02be2 ZD |
4366 | if (!a) |
4367 | return false; | |
8b11a64c | 4368 | |
b1b02be2 ZD |
4369 | if (!b) |
4370 | return true; | |
4371 | ||
4372 | if (a->cost < b->cost) | |
4373 | return true; | |
4374 | ||
4375 | if (a->cost > b->cost) | |
4376 | return false; | |
4377 | ||
4378 | /* In case the costs are the same, prefer the cheaper candidate. */ | |
4379 | if (a->cand->cost < b->cand->cost) | |
4380 | return true; | |
4381 | ||
4382 | return false; | |
4383 | } | |
4384 | ||
4385 | /* Computes the cost field of IVS structure. */ | |
4386 | ||
4387 | static void | |
4388 | iv_ca_recount_cost (struct ivopts_data *data, struct iv_ca *ivs) | |
4389 | { | |
4390 | unsigned cost = 0; | |
4391 | ||
4392 | cost += ivs->cand_use_cost; | |
4393 | cost += ivs->cand_cost; | |
4394 | cost += ivopts_global_cost_for_size (data, ivs->n_regs); | |
4395 | ||
4396 | ivs->cost = cost; | |
4397 | } | |
4398 | ||
9be872b7 ZD |
4399 | /* Remove invariants in set INVS to set IVS. */ |
4400 | ||
4401 | static void | |
4402 | iv_ca_set_remove_invariants (struct iv_ca *ivs, bitmap invs) | |
4403 | { | |
4404 | bitmap_iterator bi; | |
4405 | unsigned iid; | |
4406 | ||
4407 | if (!invs) | |
4408 | return; | |
4409 | ||
4410 | EXECUTE_IF_SET_IN_BITMAP (invs, 0, iid, bi) | |
4411 | { | |
4412 | ivs->n_invariant_uses[iid]--; | |
4413 | if (ivs->n_invariant_uses[iid] == 0) | |
4414 | ivs->n_regs--; | |
4415 | } | |
4416 | } | |
4417 | ||
b1b02be2 ZD |
4418 | /* Set USE not to be expressed by any candidate in IVS. */ |
4419 | ||
4420 | static void | |
4421 | iv_ca_set_no_cp (struct ivopts_data *data, struct iv_ca *ivs, | |
4422 | struct iv_use *use) | |
4423 | { | |
9be872b7 | 4424 | unsigned uid = use->id, cid; |
b1b02be2 | 4425 | struct cost_pair *cp; |
b1b02be2 ZD |
4426 | |
4427 | cp = ivs->cand_for_use[uid]; | |
4428 | if (!cp) | |
4429 | return; | |
4430 | cid = cp->cand->id; | |
4431 | ||
4432 | ivs->bad_uses++; | |
4433 | ivs->cand_for_use[uid] = NULL; | |
4434 | ivs->n_cand_uses[cid]--; | |
4435 | ||
4436 | if (ivs->n_cand_uses[cid] == 0) | |
8b11a64c | 4437 | { |
b1b02be2 ZD |
4438 | bitmap_clear_bit (ivs->cands, cid); |
4439 | /* Do not count the pseudocandidates. */ | |
4440 | if (cp->cand->iv) | |
4441 | ivs->n_regs--; | |
36f5ada1 | 4442 | ivs->n_cands--; |
b1b02be2 | 4443 | ivs->cand_cost -= cp->cand->cost; |
9be872b7 ZD |
4444 | |
4445 | iv_ca_set_remove_invariants (ivs, cp->cand->depends_on); | |
b1b02be2 ZD |
4446 | } |
4447 | ||
4448 | ivs->cand_use_cost -= cp->cost; | |
4449 | ||
9be872b7 ZD |
4450 | iv_ca_set_remove_invariants (ivs, cp->depends_on); |
4451 | iv_ca_recount_cost (data, ivs); | |
4452 | } | |
4453 | ||
4454 | /* Add invariants in set INVS to set IVS. */ | |
80cad5fa | 4455 | |
9be872b7 ZD |
4456 | static void |
4457 | iv_ca_set_add_invariants (struct iv_ca *ivs, bitmap invs) | |
4458 | { | |
4459 | bitmap_iterator bi; | |
4460 | unsigned iid; | |
4461 | ||
4462 | if (!invs) | |
4463 | return; | |
4464 | ||
4465 | EXECUTE_IF_SET_IN_BITMAP (invs, 0, iid, bi) | |
b1b02be2 | 4466 | { |
9be872b7 ZD |
4467 | ivs->n_invariant_uses[iid]++; |
4468 | if (ivs->n_invariant_uses[iid] == 1) | |
4469 | ivs->n_regs++; | |
8b11a64c | 4470 | } |
b1b02be2 ZD |
4471 | } |
4472 | ||
4473 | /* Set cost pair for USE in set IVS to CP. */ | |
4474 | ||
4475 | static void | |
4476 | iv_ca_set_cp (struct ivopts_data *data, struct iv_ca *ivs, | |
4477 | struct iv_use *use, struct cost_pair *cp) | |
4478 | { | |
9be872b7 | 4479 | unsigned uid = use->id, cid; |
b1b02be2 ZD |
4480 | |
4481 | if (ivs->cand_for_use[uid] == cp) | |
4482 | return; | |
4483 | ||
4484 | if (ivs->cand_for_use[uid]) | |
4485 | iv_ca_set_no_cp (data, ivs, use); | |
4486 | ||
4487 | if (cp) | |
8b11a64c | 4488 | { |
b1b02be2 | 4489 | cid = cp->cand->id; |
8b11a64c | 4490 | |
b1b02be2 ZD |
4491 | ivs->bad_uses--; |
4492 | ivs->cand_for_use[uid] = cp; | |
4493 | ivs->n_cand_uses[cid]++; | |
4494 | if (ivs->n_cand_uses[cid] == 1) | |
8b11a64c | 4495 | { |
b1b02be2 ZD |
4496 | bitmap_set_bit (ivs->cands, cid); |
4497 | /* Do not count the pseudocandidates. */ | |
4498 | if (cp->cand->iv) | |
4499 | ivs->n_regs++; | |
36f5ada1 | 4500 | ivs->n_cands++; |
b1b02be2 | 4501 | ivs->cand_cost += cp->cand->cost; |
b1b02be2 | 4502 | |
9be872b7 | 4503 | iv_ca_set_add_invariants (ivs, cp->cand->depends_on); |
8b11a64c ZD |
4504 | } |
4505 | ||
9be872b7 ZD |
4506 | ivs->cand_use_cost += cp->cost; |
4507 | iv_ca_set_add_invariants (ivs, cp->depends_on); | |
b1b02be2 | 4508 | iv_ca_recount_cost (data, ivs); |
87c476a2 | 4509 | } |
b1b02be2 ZD |
4510 | } |
4511 | ||
4512 | /* Extend set IVS by expressing USE by some of the candidates in it | |
4513 | if possible. */ | |
4514 | ||
4515 | static void | |
4516 | iv_ca_add_use (struct ivopts_data *data, struct iv_ca *ivs, | |
4517 | struct iv_use *use) | |
4518 | { | |
4519 | struct cost_pair *best_cp = NULL, *cp; | |
4520 | bitmap_iterator bi; | |
4521 | unsigned i; | |
8b11a64c | 4522 | |
b1b02be2 ZD |
4523 | gcc_assert (ivs->upto >= use->id); |
4524 | ||
4525 | if (ivs->upto == use->id) | |
4526 | { | |
4527 | ivs->upto++; | |
4528 | ivs->bad_uses++; | |
4529 | } | |
8b11a64c | 4530 | |
b1b02be2 ZD |
4531 | EXECUTE_IF_SET_IN_BITMAP (ivs->cands, 0, i, bi) |
4532 | { | |
4533 | cp = get_use_iv_cost (data, use, iv_cand (data, i)); | |
8b11a64c | 4534 | |
b1b02be2 ZD |
4535 | if (cheaper_cost_pair (cp, best_cp)) |
4536 | best_cp = cp; | |
4537 | } | |
8b11a64c | 4538 | |
b1b02be2 | 4539 | iv_ca_set_cp (data, ivs, use, best_cp); |
8b11a64c ZD |
4540 | } |
4541 | ||
b1b02be2 | 4542 | /* Get cost for assignment IVS. */ |
8b11a64c ZD |
4543 | |
4544 | static unsigned | |
b1b02be2 ZD |
4545 | iv_ca_cost (struct iv_ca *ivs) |
4546 | { | |
4547 | return (ivs->bad_uses ? INFTY : ivs->cost); | |
4548 | } | |
4549 | ||
4550 | /* Returns true if all dependences of CP are among invariants in IVS. */ | |
4551 | ||
4552 | static bool | |
4553 | iv_ca_has_deps (struct iv_ca *ivs, struct cost_pair *cp) | |
8b11a64c ZD |
4554 | { |
4555 | unsigned i; | |
87c476a2 | 4556 | bitmap_iterator bi; |
8b11a64c | 4557 | |
b1b02be2 ZD |
4558 | if (!cp->depends_on) |
4559 | return true; | |
4560 | ||
4561 | EXECUTE_IF_SET_IN_BITMAP (cp->depends_on, 0, i, bi) | |
8b11a64c | 4562 | { |
b1b02be2 ZD |
4563 | if (ivs->n_invariant_uses[i] == 0) |
4564 | return false; | |
4565 | } | |
4566 | ||
4567 | return true; | |
4568 | } | |
4569 | ||
4570 | /* Creates change of expressing USE by NEW_CP instead of OLD_CP and chains | |
4571 | it before NEXT_CHANGE. */ | |
4572 | ||
4573 | static struct iv_ca_delta * | |
4574 | iv_ca_delta_add (struct iv_use *use, struct cost_pair *old_cp, | |
4575 | struct cost_pair *new_cp, struct iv_ca_delta *next_change) | |
4576 | { | |
4577 | struct iv_ca_delta *change = xmalloc (sizeof (struct iv_ca_delta)); | |
4578 | ||
4579 | change->use = use; | |
4580 | change->old_cp = old_cp; | |
4581 | change->new_cp = new_cp; | |
4582 | change->next_change = next_change; | |
4583 | ||
4584 | return change; | |
4585 | } | |
4586 | ||
36f5ada1 | 4587 | /* Joins two lists of changes L1 and L2. Destructive -- old lists |
6c6cfbfd | 4588 | are rewritten. */ |
36f5ada1 ZD |
4589 | |
4590 | static struct iv_ca_delta * | |
4591 | iv_ca_delta_join (struct iv_ca_delta *l1, struct iv_ca_delta *l2) | |
4592 | { | |
4593 | struct iv_ca_delta *last; | |
4594 | ||
4595 | if (!l2) | |
4596 | return l1; | |
4597 | ||
4598 | if (!l1) | |
4599 | return l2; | |
4600 | ||
4601 | for (last = l1; last->next_change; last = last->next_change) | |
4602 | continue; | |
4603 | last->next_change = l2; | |
4604 | ||
4605 | return l1; | |
4606 | } | |
4607 | ||
b1b02be2 ZD |
4608 | /* Returns candidate by that USE is expressed in IVS. */ |
4609 | ||
4610 | static struct cost_pair * | |
4611 | iv_ca_cand_for_use (struct iv_ca *ivs, struct iv_use *use) | |
4612 | { | |
4613 | return ivs->cand_for_use[use->id]; | |
4614 | } | |
4615 | ||
36f5ada1 ZD |
4616 | /* Reverse the list of changes DELTA, forming the inverse to it. */ |
4617 | ||
4618 | static struct iv_ca_delta * | |
4619 | iv_ca_delta_reverse (struct iv_ca_delta *delta) | |
4620 | { | |
4621 | struct iv_ca_delta *act, *next, *prev = NULL; | |
4622 | struct cost_pair *tmp; | |
4623 | ||
4624 | for (act = delta; act; act = next) | |
4625 | { | |
4626 | next = act->next_change; | |
4627 | act->next_change = prev; | |
4628 | prev = act; | |
4629 | ||
4630 | tmp = act->old_cp; | |
4631 | act->old_cp = act->new_cp; | |
4632 | act->new_cp = tmp; | |
4633 | } | |
4634 | ||
4635 | return prev; | |
4636 | } | |
4637 | ||
b1b02be2 ZD |
4638 | /* Commit changes in DELTA to IVS. If FORWARD is false, the changes are |
4639 | reverted instead. */ | |
4640 | ||
4641 | static void | |
4642 | iv_ca_delta_commit (struct ivopts_data *data, struct iv_ca *ivs, | |
4643 | struct iv_ca_delta *delta, bool forward) | |
4644 | { | |
4645 | struct cost_pair *from, *to; | |
36f5ada1 | 4646 | struct iv_ca_delta *act; |
b1b02be2 | 4647 | |
36f5ada1 ZD |
4648 | if (!forward) |
4649 | delta = iv_ca_delta_reverse (delta); | |
b1b02be2 | 4650 | |
36f5ada1 ZD |
4651 | for (act = delta; act; act = act->next_change) |
4652 | { | |
4653 | from = act->old_cp; | |
4654 | to = act->new_cp; | |
4655 | gcc_assert (iv_ca_cand_for_use (ivs, act->use) == from); | |
4656 | iv_ca_set_cp (data, ivs, act->use, to); | |
8b11a64c | 4657 | } |
36f5ada1 ZD |
4658 | |
4659 | if (!forward) | |
4660 | iv_ca_delta_reverse (delta); | |
b1b02be2 | 4661 | } |
8b11a64c | 4662 | |
b1b02be2 | 4663 | /* Returns true if CAND is used in IVS. */ |
8b11a64c | 4664 | |
b1b02be2 ZD |
4665 | static bool |
4666 | iv_ca_cand_used_p (struct iv_ca *ivs, struct iv_cand *cand) | |
4667 | { | |
4668 | return ivs->n_cand_uses[cand->id] > 0; | |
4669 | } | |
8b11a64c | 4670 | |
36f5ada1 ZD |
4671 | /* Returns number of induction variable candidates in the set IVS. */ |
4672 | ||
4673 | static unsigned | |
4674 | iv_ca_n_cands (struct iv_ca *ivs) | |
4675 | { | |
4676 | return ivs->n_cands; | |
4677 | } | |
4678 | ||
b1b02be2 ZD |
4679 | /* Free the list of changes DELTA. */ |
4680 | ||
4681 | static void | |
4682 | iv_ca_delta_free (struct iv_ca_delta **delta) | |
4683 | { | |
4684 | struct iv_ca_delta *act, *next; | |
4685 | ||
4686 | for (act = *delta; act; act = next) | |
87c476a2 | 4687 | { |
b1b02be2 ZD |
4688 | next = act->next_change; |
4689 | free (act); | |
87c476a2 | 4690 | } |
8b11a64c | 4691 | |
b1b02be2 ZD |
4692 | *delta = NULL; |
4693 | } | |
4694 | ||
4695 | /* Allocates new iv candidates assignment. */ | |
4696 | ||
4697 | static struct iv_ca * | |
4698 | iv_ca_new (struct ivopts_data *data) | |
4699 | { | |
4700 | struct iv_ca *nw = xmalloc (sizeof (struct iv_ca)); | |
8b11a64c | 4701 | |
b1b02be2 ZD |
4702 | nw->upto = 0; |
4703 | nw->bad_uses = 0; | |
4704 | nw->cand_for_use = xcalloc (n_iv_uses (data), sizeof (struct cost_pair *)); | |
4705 | nw->n_cand_uses = xcalloc (n_iv_cands (data), sizeof (unsigned)); | |
8bdbfff5 | 4706 | nw->cands = BITMAP_ALLOC (NULL); |
36f5ada1 | 4707 | nw->n_cands = 0; |
b1b02be2 ZD |
4708 | nw->n_regs = 0; |
4709 | nw->cand_use_cost = 0; | |
4710 | nw->cand_cost = 0; | |
4711 | nw->n_invariant_uses = xcalloc (data->max_inv_id + 1, sizeof (unsigned)); | |
4712 | nw->cost = 0; | |
4713 | ||
4714 | return nw; | |
4715 | } | |
4716 | ||
4717 | /* Free memory occupied by the set IVS. */ | |
4718 | ||
4719 | static void | |
4720 | iv_ca_free (struct iv_ca **ivs) | |
4721 | { | |
4722 | free ((*ivs)->cand_for_use); | |
4723 | free ((*ivs)->n_cand_uses); | |
8bdbfff5 | 4724 | BITMAP_FREE ((*ivs)->cands); |
b1b02be2 ZD |
4725 | free ((*ivs)->n_invariant_uses); |
4726 | free (*ivs); | |
4727 | *ivs = NULL; | |
4728 | } | |
4729 | ||
4730 | /* Dumps IVS to FILE. */ | |
4731 | ||
4732 | static void | |
4733 | iv_ca_dump (struct ivopts_data *data, FILE *file, struct iv_ca *ivs) | |
4734 | { | |
4735 | const char *pref = " invariants "; | |
4736 | unsigned i; | |
4737 | ||
4738 | fprintf (file, " cost %d\n", iv_ca_cost (ivs)); | |
4739 | bitmap_print (file, ivs->cands, " candidates ","\n"); | |
4740 | ||
4741 | for (i = 1; i <= data->max_inv_id; i++) | |
4742 | if (ivs->n_invariant_uses[i]) | |
4743 | { | |
4744 | fprintf (file, "%s%d", pref, i); | |
4745 | pref = ", "; | |
4746 | } | |
4747 | fprintf (file, "\n"); | |
4748 | } | |
4749 | ||
4750 | /* Try changing candidate in IVS to CAND for each use. Return cost of the | |
36f5ada1 ZD |
4751 | new set, and store differences in DELTA. Number of induction variables |
4752 | in the new set is stored to N_IVS. */ | |
b1b02be2 ZD |
4753 | |
4754 | static unsigned | |
4755 | iv_ca_extend (struct ivopts_data *data, struct iv_ca *ivs, | |
36f5ada1 ZD |
4756 | struct iv_cand *cand, struct iv_ca_delta **delta, |
4757 | unsigned *n_ivs) | |
b1b02be2 ZD |
4758 | { |
4759 | unsigned i, cost; | |
4760 | struct iv_use *use; | |
4761 | struct cost_pair *old_cp, *new_cp; | |
4762 | ||
4763 | *delta = NULL; | |
4764 | for (i = 0; i < ivs->upto; i++) | |
4765 | { | |
4766 | use = iv_use (data, i); | |
4767 | old_cp = iv_ca_cand_for_use (ivs, use); | |
4768 | ||
4769 | if (old_cp | |
4770 | && old_cp->cand == cand) | |
4771 | continue; | |
4772 | ||
4773 | new_cp = get_use_iv_cost (data, use, cand); | |
4774 | if (!new_cp) | |
4775 | continue; | |
4776 | ||
4777 | if (!iv_ca_has_deps (ivs, new_cp)) | |
4778 | continue; | |
4779 | ||
4780 | if (!cheaper_cost_pair (new_cp, old_cp)) | |
4781 | continue; | |
4782 | ||
4783 | *delta = iv_ca_delta_add (use, old_cp, new_cp, *delta); | |
4784 | } | |
4785 | ||
4786 | iv_ca_delta_commit (data, ivs, *delta, true); | |
4787 | cost = iv_ca_cost (ivs); | |
36f5ada1 ZD |
4788 | if (n_ivs) |
4789 | *n_ivs = iv_ca_n_cands (ivs); | |
b1b02be2 | 4790 | iv_ca_delta_commit (data, ivs, *delta, false); |
8b11a64c ZD |
4791 | |
4792 | return cost; | |
4793 | } | |
4794 | ||
a0eca485 | 4795 | /* Try narrowing set IVS by removing CAND. Return the cost of |
b1b02be2 | 4796 | the new set and store the differences in DELTA. */ |
8b11a64c ZD |
4797 | |
4798 | static unsigned | |
b1b02be2 ZD |
4799 | iv_ca_narrow (struct ivopts_data *data, struct iv_ca *ivs, |
4800 | struct iv_cand *cand, struct iv_ca_delta **delta) | |
8b11a64c | 4801 | { |
b1b02be2 ZD |
4802 | unsigned i, ci; |
4803 | struct iv_use *use; | |
4804 | struct cost_pair *old_cp, *new_cp, *cp; | |
4805 | bitmap_iterator bi; | |
4806 | struct iv_cand *cnd; | |
4807 | unsigned cost; | |
4808 | ||
4809 | *delta = NULL; | |
4810 | for (i = 0; i < n_iv_uses (data); i++) | |
4811 | { | |
4812 | use = iv_use (data, i); | |
4813 | ||
4814 | old_cp = iv_ca_cand_for_use (ivs, use); | |
4815 | if (old_cp->cand != cand) | |
4816 | continue; | |
4817 | ||
4818 | new_cp = NULL; | |
4819 | ||
4820 | if (data->consider_all_candidates) | |
4821 | { | |
4822 | EXECUTE_IF_SET_IN_BITMAP (ivs->cands, 0, ci, bi) | |
4823 | { | |
4824 | if (ci == cand->id) | |
4825 | continue; | |
4826 | ||
4827 | cnd = iv_cand (data, ci); | |
4828 | ||
4829 | cp = get_use_iv_cost (data, use, cnd); | |
4830 | if (!cp) | |
4831 | continue; | |
4832 | if (!iv_ca_has_deps (ivs, cp)) | |
4833 | continue; | |
4834 | ||
4835 | if (!cheaper_cost_pair (cp, new_cp)) | |
4836 | continue; | |
4837 | ||
4838 | new_cp = cp; | |
4839 | } | |
4840 | } | |
4841 | else | |
4842 | { | |
4843 | EXECUTE_IF_AND_IN_BITMAP (use->related_cands, ivs->cands, 0, ci, bi) | |
4844 | { | |
4845 | if (ci == cand->id) | |
4846 | continue; | |
4847 | ||
4848 | cnd = iv_cand (data, ci); | |
4849 | ||
4850 | cp = get_use_iv_cost (data, use, cnd); | |
4851 | if (!cp) | |
4852 | continue; | |
4853 | if (!iv_ca_has_deps (ivs, cp)) | |
4854 | continue; | |
4855 | ||
4856 | if (!cheaper_cost_pair (cp, new_cp)) | |
4857 | continue; | |
4858 | ||
4859 | new_cp = cp; | |
4860 | } | |
4861 | } | |
4862 | ||
4863 | if (!new_cp) | |
4864 | { | |
4865 | iv_ca_delta_free (delta); | |
4866 | return INFTY; | |
4867 | } | |
4868 | ||
4869 | *delta = iv_ca_delta_add (use, old_cp, new_cp, *delta); | |
4870 | } | |
4871 | ||
4872 | iv_ca_delta_commit (data, ivs, *delta, true); | |
4873 | cost = iv_ca_cost (ivs); | |
4874 | iv_ca_delta_commit (data, ivs, *delta, false); | |
4875 | ||
4876 | return cost; | |
8b11a64c ZD |
4877 | } |
4878 | ||
36f5ada1 ZD |
4879 | /* Try optimizing the set of candidates IVS by removing candidates different |
4880 | from to EXCEPT_CAND from it. Return cost of the new set, and store | |
4881 | differences in DELTA. */ | |
4882 | ||
4883 | static unsigned | |
4884 | iv_ca_prune (struct ivopts_data *data, struct iv_ca *ivs, | |
4885 | struct iv_cand *except_cand, struct iv_ca_delta **delta) | |
4886 | { | |
4887 | bitmap_iterator bi; | |
4888 | struct iv_ca_delta *act_delta, *best_delta; | |
4889 | unsigned i, best_cost, acost; | |
4890 | struct iv_cand *cand; | |
4891 | ||
4892 | best_delta = NULL; | |
4893 | best_cost = iv_ca_cost (ivs); | |
4894 | ||
4895 | EXECUTE_IF_SET_IN_BITMAP (ivs->cands, 0, i, bi) | |
4896 | { | |
4897 | cand = iv_cand (data, i); | |
4898 | ||
4899 | if (cand == except_cand) | |
4900 | continue; | |
4901 | ||
4902 | acost = iv_ca_narrow (data, ivs, cand, &act_delta); | |
4903 | ||
4904 | if (acost < best_cost) | |
4905 | { | |
4906 | best_cost = acost; | |
4907 | iv_ca_delta_free (&best_delta); | |
4908 | best_delta = act_delta; | |
4909 | } | |
4910 | else | |
4911 | iv_ca_delta_free (&act_delta); | |
4912 | } | |
4913 | ||
4914 | if (!best_delta) | |
4915 | { | |
4916 | *delta = NULL; | |
4917 | return best_cost; | |
4918 | } | |
4919 | ||
4920 | /* Recurse to possibly remove other unnecessary ivs. */ | |
4921 | iv_ca_delta_commit (data, ivs, best_delta, true); | |
4922 | best_cost = iv_ca_prune (data, ivs, except_cand, delta); | |
4923 | iv_ca_delta_commit (data, ivs, best_delta, false); | |
4924 | *delta = iv_ca_delta_join (best_delta, *delta); | |
4925 | return best_cost; | |
4926 | } | |
4927 | ||
b1b02be2 | 4928 | /* Tries to extend the sets IVS in the best possible way in order |
8b11a64c ZD |
4929 | to express the USE. */ |
4930 | ||
4931 | static bool | |
b1b02be2 | 4932 | try_add_cand_for (struct ivopts_data *data, struct iv_ca *ivs, |
8b11a64c ZD |
4933 | struct iv_use *use) |
4934 | { | |
b1b02be2 | 4935 | unsigned best_cost, act_cost; |
8b11a64c | 4936 | unsigned i; |
38b0dcb8 ZD |
4937 | bitmap_iterator bi; |
4938 | struct iv_cand *cand; | |
b1b02be2 ZD |
4939 | struct iv_ca_delta *best_delta = NULL, *act_delta; |
4940 | struct cost_pair *cp; | |
4941 | ||
4942 | iv_ca_add_use (data, ivs, use); | |
4943 | best_cost = iv_ca_cost (ivs); | |
8b11a64c | 4944 | |
b1b02be2 ZD |
4945 | cp = iv_ca_cand_for_use (ivs, use); |
4946 | if (cp) | |
4947 | { | |
4948 | best_delta = iv_ca_delta_add (use, NULL, cp, NULL); | |
4949 | iv_ca_set_no_cp (data, ivs, use); | |
4950 | } | |
8b11a64c | 4951 | |
38b0dcb8 ZD |
4952 | /* First try important candidates. Only if it fails, try the specific ones. |
4953 | Rationale -- in loops with many variables the best choice often is to use | |
4954 | just one generic biv. If we added here many ivs specific to the uses, | |
4955 | the optimization algorithm later would be likely to get stuck in a local | |
4956 | minimum, thus causing us to create too many ivs. The approach from | |
1c170b5e | 4957 | few ivs to more seems more likely to be successful -- starting from few |
38b0dcb8 ZD |
4958 | ivs, replacing an expensive use by a specific iv should always be a |
4959 | win. */ | |
4960 | EXECUTE_IF_SET_IN_BITMAP (data->important_candidates, 0, i, bi) | |
8b11a64c | 4961 | { |
38b0dcb8 ZD |
4962 | cand = iv_cand (data, i); |
4963 | ||
b1b02be2 | 4964 | if (iv_ca_cand_used_p (ivs, cand)) |
8b11a64c ZD |
4965 | continue; |
4966 | ||
b1b02be2 ZD |
4967 | cp = get_use_iv_cost (data, use, cand); |
4968 | if (!cp) | |
4969 | continue; | |
4970 | ||
4971 | iv_ca_set_cp (data, ivs, use, cp); | |
36f5ada1 | 4972 | act_cost = iv_ca_extend (data, ivs, cand, &act_delta, NULL); |
b1b02be2 ZD |
4973 | iv_ca_set_no_cp (data, ivs, use); |
4974 | act_delta = iv_ca_delta_add (use, NULL, cp, act_delta); | |
8b11a64c ZD |
4975 | |
4976 | if (act_cost < best_cost) | |
4977 | { | |
4978 | best_cost = act_cost; | |
b1b02be2 ZD |
4979 | |
4980 | iv_ca_delta_free (&best_delta); | |
4981 | best_delta = act_delta; | |
8b11a64c | 4982 | } |
b1b02be2 ZD |
4983 | else |
4984 | iv_ca_delta_free (&act_delta); | |
8b11a64c ZD |
4985 | } |
4986 | ||
38b0dcb8 ZD |
4987 | if (best_cost == INFTY) |
4988 | { | |
4989 | for (i = 0; i < use->n_map_members; i++) | |
4990 | { | |
4991 | cp = use->cost_map + i; | |
b1b02be2 ZD |
4992 | cand = cp->cand; |
4993 | if (!cand) | |
38b0dcb8 ZD |
4994 | continue; |
4995 | ||
4996 | /* Already tried this. */ | |
b1b02be2 ZD |
4997 | if (cand->important) |
4998 | continue; | |
4999 | ||
5000 | if (iv_ca_cand_used_p (ivs, cand)) | |
38b0dcb8 ZD |
5001 | continue; |
5002 | ||
b1b02be2 ZD |
5003 | act_delta = NULL; |
5004 | iv_ca_set_cp (data, ivs, use, cp); | |
36f5ada1 | 5005 | act_cost = iv_ca_extend (data, ivs, cand, &act_delta, NULL); |
b1b02be2 ZD |
5006 | iv_ca_set_no_cp (data, ivs, use); |
5007 | act_delta = iv_ca_delta_add (use, iv_ca_cand_for_use (ivs, use), | |
5008 | cp, act_delta); | |
38b0dcb8 ZD |
5009 | |
5010 | if (act_cost < best_cost) | |
5011 | { | |
5012 | best_cost = act_cost; | |
b1b02be2 ZD |
5013 | |
5014 | if (best_delta) | |
5015 | iv_ca_delta_free (&best_delta); | |
5016 | best_delta = act_delta; | |
38b0dcb8 | 5017 | } |
b1b02be2 ZD |
5018 | else |
5019 | iv_ca_delta_free (&act_delta); | |
38b0dcb8 ZD |
5020 | } |
5021 | } | |
5022 | ||
b1b02be2 ZD |
5023 | iv_ca_delta_commit (data, ivs, best_delta, true); |
5024 | iv_ca_delta_free (&best_delta); | |
8b11a64c ZD |
5025 | |
5026 | return (best_cost != INFTY); | |
5027 | } | |
5028 | ||
b1b02be2 | 5029 | /* Finds an initial assignment of candidates to uses. */ |
8b11a64c | 5030 | |
b1b02be2 ZD |
5031 | static struct iv_ca * |
5032 | get_initial_solution (struct ivopts_data *data) | |
8b11a64c | 5033 | { |
b1b02be2 | 5034 | struct iv_ca *ivs = iv_ca_new (data); |
8b11a64c ZD |
5035 | unsigned i; |
5036 | ||
5037 | for (i = 0; i < n_iv_uses (data); i++) | |
b1b02be2 ZD |
5038 | if (!try_add_cand_for (data, ivs, iv_use (data, i))) |
5039 | { | |
5040 | iv_ca_free (&ivs); | |
5041 | return NULL; | |
5042 | } | |
8b11a64c | 5043 | |
b1b02be2 | 5044 | return ivs; |
8b11a64c ZD |
5045 | } |
5046 | ||
b1b02be2 | 5047 | /* Tries to improve set of induction variables IVS. */ |
8b11a64c ZD |
5048 | |
5049 | static bool | |
b1b02be2 | 5050 | try_improve_iv_set (struct ivopts_data *data, struct iv_ca *ivs) |
8b11a64c | 5051 | { |
36f5ada1 ZD |
5052 | unsigned i, acost, best_cost = iv_ca_cost (ivs), n_ivs; |
5053 | struct iv_ca_delta *best_delta = NULL, *act_delta, *tmp_delta; | |
b1b02be2 | 5054 | struct iv_cand *cand; |
8b11a64c | 5055 | |
36f5ada1 | 5056 | /* Try extending the set of induction variables by one. */ |
8b11a64c ZD |
5057 | for (i = 0; i < n_iv_cands (data); i++) |
5058 | { | |
b1b02be2 ZD |
5059 | cand = iv_cand (data, i); |
5060 | ||
5061 | if (iv_ca_cand_used_p (ivs, cand)) | |
36f5ada1 ZD |
5062 | continue; |
5063 | ||
5064 | acost = iv_ca_extend (data, ivs, cand, &act_delta, &n_ivs); | |
5065 | if (!act_delta) | |
5066 | continue; | |
5067 | ||
5068 | /* If we successfully added the candidate and the set is small enough, | |
5069 | try optimizing it by removing other candidates. */ | |
5070 | if (n_ivs <= ALWAYS_PRUNE_CAND_SET_BOUND) | |
5071 | { | |
5072 | iv_ca_delta_commit (data, ivs, act_delta, true); | |
5073 | acost = iv_ca_prune (data, ivs, cand, &tmp_delta); | |
5074 | iv_ca_delta_commit (data, ivs, act_delta, false); | |
5075 | act_delta = iv_ca_delta_join (act_delta, tmp_delta); | |
5076 | } | |
8b11a64c | 5077 | |
b1b02be2 | 5078 | if (acost < best_cost) |
8b11a64c | 5079 | { |
b1b02be2 | 5080 | best_cost = acost; |
36f5ada1 | 5081 | iv_ca_delta_free (&best_delta); |
b1b02be2 | 5082 | best_delta = act_delta; |
8b11a64c | 5083 | } |
8b11a64c | 5084 | else |
b1b02be2 | 5085 | iv_ca_delta_free (&act_delta); |
8b11a64c ZD |
5086 | } |
5087 | ||
b1b02be2 | 5088 | if (!best_delta) |
36f5ada1 ZD |
5089 | { |
5090 | /* Try removing the candidates from the set instead. */ | |
5091 | best_cost = iv_ca_prune (data, ivs, NULL, &best_delta); | |
5092 | ||
5093 | /* Nothing more we can do. */ | |
5094 | if (!best_delta) | |
5095 | return false; | |
5096 | } | |
8b11a64c | 5097 | |
b1b02be2 | 5098 | iv_ca_delta_commit (data, ivs, best_delta, true); |
36f5ada1 | 5099 | gcc_assert (best_cost == iv_ca_cost (ivs)); |
b1b02be2 | 5100 | iv_ca_delta_free (&best_delta); |
8b11a64c ZD |
5101 | return true; |
5102 | } | |
5103 | ||
5104 | /* Attempts to find the optimal set of induction variables. We do simple | |
5105 | greedy heuristic -- we try to replace at most one candidate in the selected | |
5106 | solution and remove the unused ivs while this improves the cost. */ | |
5107 | ||
b1b02be2 | 5108 | static struct iv_ca * |
8b11a64c ZD |
5109 | find_optimal_iv_set (struct ivopts_data *data) |
5110 | { | |
b1b02be2 ZD |
5111 | unsigned i; |
5112 | struct iv_ca *set; | |
8b11a64c ZD |
5113 | struct iv_use *use; |
5114 | ||
b1b02be2 ZD |
5115 | /* Get the initial solution. */ |
5116 | set = get_initial_solution (data); | |
5117 | if (!set) | |
8b11a64c ZD |
5118 | { |
5119 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
5120 | fprintf (dump_file, "Unable to substitute for ivs, failed.\n"); | |
8b11a64c ZD |
5121 | return NULL; |
5122 | } | |
5123 | ||
5124 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
5125 | { | |
b1b02be2 ZD |
5126 | fprintf (dump_file, "Initial set of candidates:\n"); |
5127 | iv_ca_dump (data, dump_file, set); | |
8b11a64c ZD |
5128 | } |
5129 | ||
b1b02be2 | 5130 | while (try_improve_iv_set (data, set)) |
8b11a64c ZD |
5131 | { |
5132 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
5133 | { | |
b1b02be2 ZD |
5134 | fprintf (dump_file, "Improved to:\n"); |
5135 | iv_ca_dump (data, dump_file, set); | |
8b11a64c ZD |
5136 | } |
5137 | } | |
5138 | ||
5139 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
b1b02be2 | 5140 | fprintf (dump_file, "Final cost %d\n\n", iv_ca_cost (set)); |
8b11a64c ZD |
5141 | |
5142 | for (i = 0; i < n_iv_uses (data); i++) | |
5143 | { | |
5144 | use = iv_use (data, i); | |
b1b02be2 | 5145 | use->selected = iv_ca_cand_for_use (set, use)->cand; |
8b11a64c ZD |
5146 | } |
5147 | ||
8b11a64c ZD |
5148 | return set; |
5149 | } | |
5150 | ||
5151 | /* Creates a new induction variable corresponding to CAND. */ | |
5152 | ||
5153 | static void | |
5154 | create_new_iv (struct ivopts_data *data, struct iv_cand *cand) | |
5155 | { | |
5156 | block_stmt_iterator incr_pos; | |
5157 | tree base; | |
5158 | bool after = false; | |
5159 | ||
5160 | if (!cand->iv) | |
5161 | return; | |
5162 | ||
5163 | switch (cand->pos) | |
5164 | { | |
5165 | case IP_NORMAL: | |
5166 | incr_pos = bsi_last (ip_normal_pos (data->current_loop)); | |
5167 | break; | |
5168 | ||
5169 | case IP_END: | |
5170 | incr_pos = bsi_last (ip_end_pos (data->current_loop)); | |
5171 | after = true; | |
5172 | break; | |
5173 | ||
5174 | case IP_ORIGINAL: | |
5175 | /* Mark that the iv is preserved. */ | |
5176 | name_info (data, cand->var_before)->preserve_biv = true; | |
5177 | name_info (data, cand->var_after)->preserve_biv = true; | |
5178 | ||
5179 | /* Rewrite the increment so that it uses var_before directly. */ | |
5180 | find_interesting_uses_op (data, cand->var_after)->selected = cand; | |
5181 | ||
5182 | return; | |
5183 | } | |
5184 | ||
5185 | gimple_add_tmp_var (cand->var_before); | |
5186 | add_referenced_tmp_var (cand->var_before); | |
5187 | ||
5188 | base = unshare_expr (cand->iv->base); | |
5189 | ||
9be872b7 ZD |
5190 | create_iv (base, unshare_expr (cand->iv->step), |
5191 | cand->var_before, data->current_loop, | |
8b11a64c ZD |
5192 | &incr_pos, after, &cand->var_before, &cand->var_after); |
5193 | } | |
5194 | ||
5195 | /* Creates new induction variables described in SET. */ | |
5196 | ||
5197 | static void | |
b1b02be2 | 5198 | create_new_ivs (struct ivopts_data *data, struct iv_ca *set) |
8b11a64c ZD |
5199 | { |
5200 | unsigned i; | |
5201 | struct iv_cand *cand; | |
87c476a2 | 5202 | bitmap_iterator bi; |
8b11a64c | 5203 | |
b1b02be2 | 5204 | EXECUTE_IF_SET_IN_BITMAP (set->cands, 0, i, bi) |
8b11a64c ZD |
5205 | { |
5206 | cand = iv_cand (data, i); | |
5207 | create_new_iv (data, cand); | |
87c476a2 | 5208 | } |
8b11a64c ZD |
5209 | } |
5210 | ||
5211 | /* Removes statement STMT (real or a phi node). If INCLUDING_DEFINED_NAME | |
5212 | is true, remove also the ssa name defined by the statement. */ | |
5213 | ||
5214 | static void | |
5215 | remove_statement (tree stmt, bool including_defined_name) | |
5216 | { | |
5217 | if (TREE_CODE (stmt) == PHI_NODE) | |
5218 | { | |
5219 | if (!including_defined_name) | |
5220 | { | |
5221 | /* Prevent the ssa name defined by the statement from being removed. */ | |
5222 | SET_PHI_RESULT (stmt, NULL); | |
5223 | } | |
d19e3ef6 | 5224 | remove_phi_node (stmt, NULL_TREE); |
8b11a64c ZD |
5225 | } |
5226 | else | |
5227 | { | |
1a1804c2 | 5228 | block_stmt_iterator bsi = bsi_for_stmt (stmt); |
8b11a64c ZD |
5229 | |
5230 | bsi_remove (&bsi); | |
5231 | } | |
5232 | } | |
5233 | ||
5234 | /* Rewrites USE (definition of iv used in a nonlinear expression) | |
5235 | using candidate CAND. */ | |
5236 | ||
5237 | static void | |
5238 | rewrite_use_nonlinear_expr (struct ivopts_data *data, | |
5239 | struct iv_use *use, struct iv_cand *cand) | |
5240 | { | |
3520b745 | 5241 | tree comp; |
8b11a64c ZD |
5242 | tree op, stmts, tgt, ass; |
5243 | block_stmt_iterator bsi, pbsi; | |
3520b745 ZD |
5244 | |
5245 | /* An important special case -- if we are asked to express value of | |
5246 | the original iv by itself, just exit; there is no need to | |
5247 | introduce a new computation (that might also need casting the | |
5248 | variable to unsigned and back). */ | |
5249 | if (cand->pos == IP_ORIGINAL | |
5250 | && TREE_CODE (use->stmt) == MODIFY_EXPR | |
5251 | && TREE_OPERAND (use->stmt, 0) == cand->var_after) | |
5252 | { | |
5253 | op = TREE_OPERAND (use->stmt, 1); | |
5254 | ||
5255 | /* Be a bit careful. In case variable is expressed in some | |
5256 | complicated way, rewrite it so that we may get rid of this | |
5257 | complicated expression. */ | |
5258 | if ((TREE_CODE (op) == PLUS_EXPR | |
5259 | || TREE_CODE (op) == MINUS_EXPR) | |
5260 | && TREE_OPERAND (op, 0) == cand->var_before | |
5261 | && TREE_CODE (TREE_OPERAND (op, 1)) == INTEGER_CST) | |
5262 | return; | |
5263 | } | |
5264 | ||
5265 | comp = unshare_expr (get_computation (data->current_loop, | |
5266 | use, cand)); | |
1e128c5f | 5267 | switch (TREE_CODE (use->stmt)) |
8b11a64c | 5268 | { |
1e128c5f | 5269 | case PHI_NODE: |
8b11a64c ZD |
5270 | tgt = PHI_RESULT (use->stmt); |
5271 | ||
5272 | /* If we should keep the biv, do not replace it. */ | |
5273 | if (name_info (data, tgt)->preserve_biv) | |
5274 | return; | |
5275 | ||
5276 | pbsi = bsi = bsi_start (bb_for_stmt (use->stmt)); | |
5277 | while (!bsi_end_p (pbsi) | |
5278 | && TREE_CODE (bsi_stmt (pbsi)) == LABEL_EXPR) | |
5279 | { | |
5280 | bsi = pbsi; | |
5281 | bsi_next (&pbsi); | |
5282 | } | |
1e128c5f GB |
5283 | break; |
5284 | ||
5285 | case MODIFY_EXPR: | |
8b11a64c | 5286 | tgt = TREE_OPERAND (use->stmt, 0); |
1a1804c2 | 5287 | bsi = bsi_for_stmt (use->stmt); |
1e128c5f GB |
5288 | break; |
5289 | ||
5290 | default: | |
5291 | gcc_unreachable (); | |
8b11a64c | 5292 | } |
8b11a64c ZD |
5293 | |
5294 | op = force_gimple_operand (comp, &stmts, false, SSA_NAME_VAR (tgt)); | |
5295 | ||
5296 | if (TREE_CODE (use->stmt) == PHI_NODE) | |
5297 | { | |
5298 | if (stmts) | |
5299 | bsi_insert_after (&bsi, stmts, BSI_CONTINUE_LINKING); | |
5300 | ass = build2 (MODIFY_EXPR, TREE_TYPE (tgt), tgt, op); | |
5301 | bsi_insert_after (&bsi, ass, BSI_NEW_STMT); | |
5302 | remove_statement (use->stmt, false); | |
5303 | SSA_NAME_DEF_STMT (tgt) = ass; | |
5304 | } | |
5305 | else | |
5306 | { | |
5307 | if (stmts) | |
5308 | bsi_insert_before (&bsi, stmts, BSI_SAME_STMT); | |
5309 | TREE_OPERAND (use->stmt, 1) = op; | |
5310 | } | |
5311 | } | |
5312 | ||
5313 | /* Replaces ssa name in index IDX by its basic variable. Callback for | |
5314 | for_each_index. */ | |
5315 | ||
5316 | static bool | |
be35cf60 | 5317 | idx_remove_ssa_names (tree base, tree *idx, |
8b11a64c ZD |
5318 | void *data ATTRIBUTE_UNUSED) |
5319 | { | |
be35cf60 ZD |
5320 | tree *op; |
5321 | ||
8b11a64c ZD |
5322 | if (TREE_CODE (*idx) == SSA_NAME) |
5323 | *idx = SSA_NAME_VAR (*idx); | |
be35cf60 ZD |
5324 | |
5325 | if (TREE_CODE (base) == ARRAY_REF) | |
5326 | { | |
5327 | op = &TREE_OPERAND (base, 2); | |
5328 | if (*op | |
5329 | && TREE_CODE (*op) == SSA_NAME) | |
5330 | *op = SSA_NAME_VAR (*op); | |
5331 | op = &TREE_OPERAND (base, 3); | |
5332 | if (*op | |
5333 | && TREE_CODE (*op) == SSA_NAME) | |
5334 | *op = SSA_NAME_VAR (*op); | |
5335 | } | |
5336 | ||
8b11a64c ZD |
5337 | return true; |
5338 | } | |
5339 | ||
5340 | /* Unshares REF and replaces ssa names inside it by their basic variables. */ | |
5341 | ||
5342 | static tree | |
5343 | unshare_and_remove_ssa_names (tree ref) | |
5344 | { | |
5345 | ref = unshare_expr (ref); | |
5346 | for_each_index (&ref, idx_remove_ssa_names, NULL); | |
5347 | ||
5348 | return ref; | |
5349 | } | |
5350 | ||
5351 | /* Rewrites base of memory access OP with expression WITH in statement | |
5352 | pointed to by BSI. */ | |
5353 | ||
5354 | static void | |
5355 | rewrite_address_base (block_stmt_iterator *bsi, tree *op, tree with) | |
5356 | { | |
0bca51f0 | 5357 | tree bvar, var, new_name, copy, name; |
8b11a64c ZD |
5358 | tree orig; |
5359 | ||
7ccf35ed DN |
5360 | var = bvar = get_base_address (*op); |
5361 | ||
8b11a64c ZD |
5362 | if (!var || TREE_CODE (with) != SSA_NAME) |
5363 | goto do_rewrite; | |
be35cf60 ZD |
5364 | |
5365 | gcc_assert (TREE_CODE (var) != ALIGN_INDIRECT_REF); | |
5366 | gcc_assert (TREE_CODE (var) != MISALIGNED_INDIRECT_REF); | |
5367 | if (TREE_CODE (var) == INDIRECT_REF) | |
8b11a64c ZD |
5368 | var = TREE_OPERAND (var, 0); |
5369 | if (TREE_CODE (var) == SSA_NAME) | |
5370 | { | |
5371 | name = var; | |
5372 | var = SSA_NAME_VAR (var); | |
5373 | } | |
5374 | else if (DECL_P (var)) | |
5375 | name = NULL_TREE; | |
5376 | else | |
5377 | goto do_rewrite; | |
5378 | ||
8b11a64c ZD |
5379 | /* We need to add a memory tag for the variable. But we do not want |
5380 | to add it to the temporary used for the computations, since this leads | |
5381 | to problems in redundancy elimination when there are common parts | |
5382 | in two computations referring to the different arrays. So we copy | |
5383 | the variable to a new temporary. */ | |
5384 | copy = build2 (MODIFY_EXPR, void_type_node, NULL_TREE, with); | |
0bca51f0 | 5385 | |
8b11a64c ZD |
5386 | if (name) |
5387 | new_name = duplicate_ssa_name (name, copy); | |
5388 | else | |
5389 | { | |
0bca51f0 DN |
5390 | tree tag = var_ann (var)->type_mem_tag; |
5391 | tree new_ptr = create_tmp_var (TREE_TYPE (with), "ruatmp"); | |
5392 | add_referenced_tmp_var (new_ptr); | |
5393 | if (tag) | |
5394 | var_ann (new_ptr)->type_mem_tag = tag; | |
5395 | else | |
5396 | add_type_alias (new_ptr, var); | |
5397 | new_name = make_ssa_name (new_ptr, copy); | |
8b11a64c | 5398 | } |
0bca51f0 | 5399 | |
8b11a64c ZD |
5400 | TREE_OPERAND (copy, 0) = new_name; |
5401 | bsi_insert_before (bsi, copy, BSI_SAME_STMT); | |
5402 | with = new_name; | |
5403 | ||
5404 | do_rewrite: | |
5405 | ||
5406 | orig = NULL_TREE; | |
be35cf60 ZD |
5407 | gcc_assert (TREE_CODE (*op) != ALIGN_INDIRECT_REF); |
5408 | gcc_assert (TREE_CODE (*op) != MISALIGNED_INDIRECT_REF); | |
5409 | ||
5410 | if (TREE_CODE (*op) == INDIRECT_REF) | |
8b11a64c ZD |
5411 | orig = REF_ORIGINAL (*op); |
5412 | if (!orig) | |
5413 | orig = unshare_and_remove_ssa_names (*op); | |
5414 | ||
be35cf60 | 5415 | *op = build1 (INDIRECT_REF, TREE_TYPE (*op), with); |
7ccf35ed | 5416 | |
8b11a64c ZD |
5417 | /* Record the original reference, for purposes of alias analysis. */ |
5418 | REF_ORIGINAL (*op) = orig; | |
0bca51f0 DN |
5419 | |
5420 | /* Virtual operands in the original statement may have to be renamed | |
5421 | because of the replacement. */ | |
5422 | mark_new_vars_to_rename (bsi_stmt (*bsi)); | |
8b11a64c ZD |
5423 | } |
5424 | ||
5425 | /* Rewrites USE (address that is an iv) using candidate CAND. */ | |
5426 | ||
5427 | static void | |
5428 | rewrite_use_address (struct ivopts_data *data, | |
5429 | struct iv_use *use, struct iv_cand *cand) | |
5430 | { | |
5431 | tree comp = unshare_expr (get_computation (data->current_loop, | |
5432 | use, cand)); | |
1a1804c2 | 5433 | block_stmt_iterator bsi = bsi_for_stmt (use->stmt); |
8b11a64c ZD |
5434 | tree stmts; |
5435 | tree op = force_gimple_operand (comp, &stmts, true, NULL_TREE); | |
5436 | ||
5437 | if (stmts) | |
5438 | bsi_insert_before (&bsi, stmts, BSI_SAME_STMT); | |
5439 | ||
5440 | rewrite_address_base (&bsi, use->op_p, op); | |
5441 | } | |
5442 | ||
5443 | /* Rewrites USE (the condition such that one of the arguments is an iv) using | |
5444 | candidate CAND. */ | |
5445 | ||
5446 | static void | |
5447 | rewrite_use_compare (struct ivopts_data *data, | |
5448 | struct iv_use *use, struct iv_cand *cand) | |
5449 | { | |
5450 | tree comp; | |
5451 | tree *op_p, cond, op, stmts, bound; | |
1a1804c2 | 5452 | block_stmt_iterator bsi = bsi_for_stmt (use->stmt); |
8b11a64c | 5453 | enum tree_code compare; |
f5f12961 | 5454 | struct cost_pair *cp = get_use_iv_cost (data, use, cand); |
8b11a64c | 5455 | |
f5f12961 ZD |
5456 | bound = cp->value; |
5457 | if (bound) | |
8b11a64c | 5458 | { |
9e7376e5 ZD |
5459 | tree var = var_at_stmt (data->current_loop, cand, use->stmt); |
5460 | tree var_type = TREE_TYPE (var); | |
5461 | ||
f5f12961 | 5462 | compare = iv_elimination_compare (data, use); |
9e7376e5 | 5463 | bound = fold_convert (var_type, bound); |
8b11a64c ZD |
5464 | op = force_gimple_operand (unshare_expr (bound), &stmts, |
5465 | true, NULL_TREE); | |
5466 | ||
5467 | if (stmts) | |
5468 | bsi_insert_before (&bsi, stmts, BSI_SAME_STMT); | |
5469 | ||
9e7376e5 | 5470 | *use->op_p = build2 (compare, boolean_type_node, var, op); |
f430bae8 | 5471 | update_stmt (use->stmt); |
8b11a64c ZD |
5472 | return; |
5473 | } | |
5474 | ||
5475 | /* The induction variable elimination failed; just express the original | |
5476 | giv. */ | |
5477 | comp = unshare_expr (get_computation (data->current_loop, use, cand)); | |
5478 | ||
5479 | cond = *use->op_p; | |
5480 | op_p = &TREE_OPERAND (cond, 0); | |
5481 | if (TREE_CODE (*op_p) != SSA_NAME | |
5482 | || zero_p (get_iv (data, *op_p)->step)) | |
5483 | op_p = &TREE_OPERAND (cond, 1); | |
5484 | ||
5485 | op = force_gimple_operand (comp, &stmts, true, SSA_NAME_VAR (*op_p)); | |
5486 | if (stmts) | |
5487 | bsi_insert_before (&bsi, stmts, BSI_SAME_STMT); | |
5488 | ||
5489 | *op_p = op; | |
5490 | } | |
5491 | ||
5492 | /* Ensure that operand *OP_P may be used at the end of EXIT without | |
5493 | violating loop closed ssa form. */ | |
5494 | ||
5495 | static void | |
5496 | protect_loop_closed_ssa_form_use (edge exit, use_operand_p op_p) | |
5497 | { | |
5498 | basic_block def_bb; | |
5499 | struct loop *def_loop; | |
5500 | tree phi, use; | |
5501 | ||
5502 | use = USE_FROM_PTR (op_p); | |
5503 | if (TREE_CODE (use) != SSA_NAME) | |
5504 | return; | |
5505 | ||
5506 | def_bb = bb_for_stmt (SSA_NAME_DEF_STMT (use)); | |
5507 | if (!def_bb) | |
5508 | return; | |
5509 | ||
5510 | def_loop = def_bb->loop_father; | |
5511 | if (flow_bb_inside_loop_p (def_loop, exit->dest)) | |
5512 | return; | |
5513 | ||
5514 | /* Try finding a phi node that copies the value out of the loop. */ | |
bb29d951 | 5515 | for (phi = phi_nodes (exit->dest); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
5516 | if (PHI_ARG_DEF_FROM_EDGE (phi, exit) == use) |
5517 | break; | |
5518 | ||
5519 | if (!phi) | |
5520 | { | |
5521 | /* Create such a phi node. */ | |
5522 | tree new_name = duplicate_ssa_name (use, NULL); | |
5523 | ||
5524 | phi = create_phi_node (new_name, exit->dest); | |
5525 | SSA_NAME_DEF_STMT (new_name) = phi; | |
d2e398df | 5526 | add_phi_arg (phi, use, exit); |
8b11a64c ZD |
5527 | } |
5528 | ||
5529 | SET_USE (op_p, PHI_RESULT (phi)); | |
5530 | } | |
5531 | ||
5532 | /* Ensure that operands of STMT may be used at the end of EXIT without | |
5533 | violating loop closed ssa form. */ | |
5534 | ||
5535 | static void | |
5536 | protect_loop_closed_ssa_form (edge exit, tree stmt) | |
5537 | { | |
f47c96aa AM |
5538 | ssa_op_iter iter; |
5539 | use_operand_p use_p; | |
8b11a64c | 5540 | |
f47c96aa AM |
5541 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_ALL_USES) |
5542 | protect_loop_closed_ssa_form_use (exit, use_p); | |
8b11a64c ZD |
5543 | } |
5544 | ||
5545 | /* STMTS compute a value of a phi argument OP on EXIT of a loop. Arrange things | |
5546 | so that they are emitted on the correct place, and so that the loop closed | |
5547 | ssa form is preserved. */ | |
5548 | ||
5549 | static void | |
5550 | compute_phi_arg_on_exit (edge exit, tree stmts, tree op) | |
5551 | { | |
5552 | tree_stmt_iterator tsi; | |
5553 | block_stmt_iterator bsi; | |
5554 | tree phi, stmt, def, next; | |
5555 | ||
c5cbcccf | 5556 | if (!single_pred_p (exit->dest)) |
8b11a64c ZD |
5557 | split_loop_exit_edge (exit); |
5558 | ||
f430bae8 AM |
5559 | /* Ensure there is label in exit->dest, so that we can |
5560 | insert after it. */ | |
5561 | tree_block_label (exit->dest); | |
5562 | bsi = bsi_after_labels (exit->dest); | |
5563 | ||
8b11a64c ZD |
5564 | if (TREE_CODE (stmts) == STATEMENT_LIST) |
5565 | { | |
5566 | for (tsi = tsi_start (stmts); !tsi_end_p (tsi); tsi_next (&tsi)) | |
f430bae8 AM |
5567 | { |
5568 | bsi_insert_after (&bsi, tsi_stmt (tsi), BSI_NEW_STMT); | |
5569 | protect_loop_closed_ssa_form (exit, bsi_stmt (bsi)); | |
5570 | } | |
8b11a64c ZD |
5571 | } |
5572 | else | |
f430bae8 AM |
5573 | { |
5574 | bsi_insert_after (&bsi, stmts, BSI_NEW_STMT); | |
5575 | protect_loop_closed_ssa_form (exit, bsi_stmt (bsi)); | |
5576 | } | |
8b11a64c ZD |
5577 | |
5578 | if (!op) | |
5579 | return; | |
5580 | ||
5581 | for (phi = phi_nodes (exit->dest); phi; phi = next) | |
5582 | { | |
eaf0dc02 | 5583 | next = PHI_CHAIN (phi); |
8b11a64c ZD |
5584 | |
5585 | if (PHI_ARG_DEF_FROM_EDGE (phi, exit) == op) | |
5586 | { | |
5587 | def = PHI_RESULT (phi); | |
5588 | remove_statement (phi, false); | |
5589 | stmt = build2 (MODIFY_EXPR, TREE_TYPE (op), | |
5590 | def, op); | |
5591 | SSA_NAME_DEF_STMT (def) = stmt; | |
5592 | bsi_insert_after (&bsi, stmt, BSI_CONTINUE_LINKING); | |
5593 | } | |
5594 | } | |
5595 | } | |
5596 | ||
5597 | /* Rewrites the final value of USE (that is only needed outside of the loop) | |
5598 | using candidate CAND. */ | |
5599 | ||
5600 | static void | |
5601 | rewrite_use_outer (struct ivopts_data *data, | |
5602 | struct iv_use *use, struct iv_cand *cand) | |
5603 | { | |
5604 | edge exit; | |
5605 | tree value, op, stmts, tgt; | |
5606 | tree phi; | |
5607 | ||
1e128c5f GB |
5608 | switch (TREE_CODE (use->stmt)) |
5609 | { | |
5610 | case PHI_NODE: | |
5611 | tgt = PHI_RESULT (use->stmt); | |
5612 | break; | |
5613 | case MODIFY_EXPR: | |
5614 | tgt = TREE_OPERAND (use->stmt, 0); | |
5615 | break; | |
5616 | default: | |
5617 | gcc_unreachable (); | |
5618 | } | |
5619 | ||
8b11a64c ZD |
5620 | exit = single_dom_exit (data->current_loop); |
5621 | ||
5622 | if (exit) | |
5623 | { | |
5624 | if (!cand->iv) | |
5625 | { | |
f5f12961 ZD |
5626 | struct cost_pair *cp = get_use_iv_cost (data, use, cand); |
5627 | value = cp->value; | |
8b11a64c ZD |
5628 | } |
5629 | else | |
5630 | value = get_computation_at (data->current_loop, | |
5631 | use, cand, last_stmt (exit->src)); | |
5632 | ||
2f4675b4 | 5633 | value = unshare_expr (value); |
8b11a64c ZD |
5634 | op = force_gimple_operand (value, &stmts, true, SSA_NAME_VAR (tgt)); |
5635 | ||
5636 | /* If we will preserve the iv anyway and we would need to perform | |
5637 | some computation to replace the final value, do nothing. */ | |
5638 | if (stmts && name_info (data, tgt)->preserve_biv) | |
5639 | return; | |
5640 | ||
bb29d951 | 5641 | for (phi = phi_nodes (exit->dest); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
5642 | { |
5643 | use_operand_p use_p = PHI_ARG_DEF_PTR_FROM_EDGE (phi, exit); | |
5644 | ||
5645 | if (USE_FROM_PTR (use_p) == tgt) | |
5646 | SET_USE (use_p, op); | |
5647 | } | |
5648 | ||
5649 | if (stmts) | |
5650 | compute_phi_arg_on_exit (exit, stmts, op); | |
5651 | ||
5652 | /* Enable removal of the statement. We cannot remove it directly, | |
5653 | since we may still need the aliasing information attached to the | |
5654 | ssa name defined by it. */ | |
5655 | name_info (data, tgt)->iv->have_use_for = false; | |
5656 | return; | |
5657 | } | |
5658 | ||
5659 | /* If the variable is going to be preserved anyway, there is nothing to | |
5660 | do. */ | |
5661 | if (name_info (data, tgt)->preserve_biv) | |
5662 | return; | |
5663 | ||
5664 | /* Otherwise we just need to compute the iv. */ | |
5665 | rewrite_use_nonlinear_expr (data, use, cand); | |
5666 | } | |
5667 | ||
5668 | /* Rewrites USE using candidate CAND. */ | |
5669 | ||
5670 | static void | |
5671 | rewrite_use (struct ivopts_data *data, | |
5672 | struct iv_use *use, struct iv_cand *cand) | |
5673 | { | |
5674 | switch (use->type) | |
5675 | { | |
5676 | case USE_NONLINEAR_EXPR: | |
5677 | rewrite_use_nonlinear_expr (data, use, cand); | |
5678 | break; | |
5679 | ||
5680 | case USE_OUTER: | |
5681 | rewrite_use_outer (data, use, cand); | |
5682 | break; | |
5683 | ||
5684 | case USE_ADDRESS: | |
5685 | rewrite_use_address (data, use, cand); | |
5686 | break; | |
5687 | ||
5688 | case USE_COMPARE: | |
5689 | rewrite_use_compare (data, use, cand); | |
5690 | break; | |
5691 | ||
5692 | default: | |
1e128c5f | 5693 | gcc_unreachable (); |
8b11a64c | 5694 | } |
f430bae8 | 5695 | update_stmt (use->stmt); |
8b11a64c ZD |
5696 | } |
5697 | ||
5698 | /* Rewrite the uses using the selected induction variables. */ | |
5699 | ||
5700 | static void | |
5701 | rewrite_uses (struct ivopts_data *data) | |
5702 | { | |
5703 | unsigned i; | |
5704 | struct iv_cand *cand; | |
5705 | struct iv_use *use; | |
5706 | ||
5707 | for (i = 0; i < n_iv_uses (data); i++) | |
5708 | { | |
5709 | use = iv_use (data, i); | |
5710 | cand = use->selected; | |
1e128c5f | 5711 | gcc_assert (cand); |
8b11a64c ZD |
5712 | |
5713 | rewrite_use (data, use, cand); | |
5714 | } | |
5715 | } | |
5716 | ||
5717 | /* Removes the ivs that are not used after rewriting. */ | |
5718 | ||
5719 | static void | |
5720 | remove_unused_ivs (struct ivopts_data *data) | |
5721 | { | |
5722 | unsigned j; | |
87c476a2 | 5723 | bitmap_iterator bi; |
8b11a64c | 5724 | |
87c476a2 | 5725 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, j, bi) |
8b11a64c ZD |
5726 | { |
5727 | struct version_info *info; | |
5728 | ||
5729 | info = ver_info (data, j); | |
5730 | if (info->iv | |
5731 | && !zero_p (info->iv->step) | |
5732 | && !info->inv_id | |
5733 | && !info->iv->have_use_for | |
5734 | && !info->preserve_biv) | |
5735 | remove_statement (SSA_NAME_DEF_STMT (info->iv->ssa_name), true); | |
87c476a2 | 5736 | } |
8b11a64c ZD |
5737 | } |
5738 | ||
5739 | /* Frees data allocated by the optimization of a single loop. */ | |
5740 | ||
5741 | static void | |
5742 | free_loop_data (struct ivopts_data *data) | |
5743 | { | |
5744 | unsigned i, j; | |
87c476a2 | 5745 | bitmap_iterator bi; |
69ebd99d | 5746 | tree obj; |
8b11a64c | 5747 | |
ca4c3169 ZD |
5748 | htab_empty (data->niters); |
5749 | ||
87c476a2 | 5750 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
8b11a64c ZD |
5751 | { |
5752 | struct version_info *info; | |
5753 | ||
5754 | info = ver_info (data, i); | |
5755 | if (info->iv) | |
5756 | free (info->iv); | |
5757 | info->iv = NULL; | |
5758 | info->has_nonlin_use = false; | |
5759 | info->preserve_biv = false; | |
5760 | info->inv_id = 0; | |
87c476a2 | 5761 | } |
8b11a64c | 5762 | bitmap_clear (data->relevant); |
b1b02be2 | 5763 | bitmap_clear (data->important_candidates); |
8b11a64c ZD |
5764 | |
5765 | for (i = 0; i < n_iv_uses (data); i++) | |
5766 | { | |
5767 | struct iv_use *use = iv_use (data, i); | |
5768 | ||
5769 | free (use->iv); | |
8bdbfff5 | 5770 | BITMAP_FREE (use->related_cands); |
8b11a64c ZD |
5771 | for (j = 0; j < use->n_map_members; j++) |
5772 | if (use->cost_map[j].depends_on) | |
8bdbfff5 | 5773 | BITMAP_FREE (use->cost_map[j].depends_on); |
8b11a64c ZD |
5774 | free (use->cost_map); |
5775 | free (use); | |
5776 | } | |
69ebd99d | 5777 | VEC_truncate (iv_use_p, data->iv_uses, 0); |
8b11a64c ZD |
5778 | |
5779 | for (i = 0; i < n_iv_cands (data); i++) | |
5780 | { | |
5781 | struct iv_cand *cand = iv_cand (data, i); | |
5782 | ||
5783 | if (cand->iv) | |
5784 | free (cand->iv); | |
9be872b7 ZD |
5785 | if (cand->depends_on) |
5786 | BITMAP_FREE (cand->depends_on); | |
8b11a64c ZD |
5787 | free (cand); |
5788 | } | |
69ebd99d | 5789 | VEC_truncate (iv_cand_p, data->iv_candidates, 0); |
8b11a64c ZD |
5790 | |
5791 | if (data->version_info_size < num_ssa_names) | |
5792 | { | |
5793 | data->version_info_size = 2 * num_ssa_names; | |
5794 | free (data->version_info); | |
5795 | data->version_info = xcalloc (data->version_info_size, | |
5796 | sizeof (struct version_info)); | |
5797 | } | |
5798 | ||
5799 | data->max_inv_id = 0; | |
5800 | ||
69ebd99d KH |
5801 | for (i = 0; VEC_iterate (tree, decl_rtl_to_reset, i, obj); i++) |
5802 | SET_DECL_RTL (obj, NULL_RTX); | |
8b11a64c | 5803 | |
69ebd99d | 5804 | VEC_truncate (tree, decl_rtl_to_reset, 0); |
8b11a64c ZD |
5805 | } |
5806 | ||
5807 | /* Finalizes data structures used by the iv optimization pass. LOOPS is the | |
5808 | loop tree. */ | |
5809 | ||
5810 | static void | |
5811 | tree_ssa_iv_optimize_finalize (struct loops *loops, struct ivopts_data *data) | |
5812 | { | |
5813 | unsigned i; | |
5814 | ||
5815 | for (i = 1; i < loops->num; i++) | |
5816 | if (loops->parray[i]) | |
5817 | { | |
5818 | free (loops->parray[i]->aux); | |
5819 | loops->parray[i]->aux = NULL; | |
5820 | } | |
5821 | ||
5822 | free_loop_data (data); | |
5823 | free (data->version_info); | |
8bdbfff5 NS |
5824 | BITMAP_FREE (data->relevant); |
5825 | BITMAP_FREE (data->important_candidates); | |
ca4c3169 | 5826 | htab_delete (data->niters); |
8b11a64c | 5827 | |
69ebd99d KH |
5828 | VEC_free (tree, heap, decl_rtl_to_reset); |
5829 | VEC_free (iv_use_p, heap, data->iv_uses); | |
5830 | VEC_free (iv_cand_p, heap, data->iv_candidates); | |
8b11a64c ZD |
5831 | } |
5832 | ||
5833 | /* Optimizes the LOOP. Returns true if anything changed. */ | |
5834 | ||
5835 | static bool | |
5836 | tree_ssa_iv_optimize_loop (struct ivopts_data *data, struct loop *loop) | |
5837 | { | |
5838 | bool changed = false; | |
b1b02be2 | 5839 | struct iv_ca *iv_ca; |
8b11a64c ZD |
5840 | edge exit; |
5841 | ||
5842 | data->current_loop = loop; | |
5843 | ||
5844 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
5845 | { | |
5846 | fprintf (dump_file, "Processing loop %d\n", loop->num); | |
5847 | ||
5848 | exit = single_dom_exit (loop); | |
5849 | if (exit) | |
5850 | { | |
5851 | fprintf (dump_file, " single exit %d -> %d, exit condition ", | |
5852 | exit->src->index, exit->dest->index); | |
5853 | print_generic_expr (dump_file, last_stmt (exit->src), TDF_SLIM); | |
5854 | fprintf (dump_file, "\n"); | |
5855 | } | |
5856 | ||
5857 | fprintf (dump_file, "\n"); | |
5858 | } | |
5859 | ||
5860 | /* For each ssa name determines whether it behaves as an induction variable | |
5861 | in some loop. */ | |
5862 | if (!find_induction_variables (data)) | |
5863 | goto finish; | |
5864 | ||
5865 | /* Finds interesting uses (item 1). */ | |
5866 | find_interesting_uses (data); | |
5867 | if (n_iv_uses (data) > MAX_CONSIDERED_USES) | |
5868 | goto finish; | |
5869 | ||
5870 | /* Finds candidates for the induction variables (item 2). */ | |
5871 | find_iv_candidates (data); | |
5872 | ||
5873 | /* Calculates the costs (item 3, part 1). */ | |
5874 | determine_use_iv_costs (data); | |
5875 | determine_iv_costs (data); | |
5876 | determine_set_costs (data); | |
5877 | ||
5878 | /* Find the optimal set of induction variables (item 3, part 2). */ | |
b1b02be2 ZD |
5879 | iv_ca = find_optimal_iv_set (data); |
5880 | if (!iv_ca) | |
8b11a64c ZD |
5881 | goto finish; |
5882 | changed = true; | |
5883 | ||
5884 | /* Create the new induction variables (item 4, part 1). */ | |
b1b02be2 ZD |
5885 | create_new_ivs (data, iv_ca); |
5886 | iv_ca_free (&iv_ca); | |
8b11a64c ZD |
5887 | |
5888 | /* Rewrite the uses (item 4, part 2). */ | |
5889 | rewrite_uses (data); | |
5890 | ||
5891 | /* Remove the ivs that are unused after rewriting. */ | |
5892 | remove_unused_ivs (data); | |
5893 | ||
8b11a64c ZD |
5894 | /* We have changed the structure of induction variables; it might happen |
5895 | that definitions in the scev database refer to some of them that were | |
5896 | eliminated. */ | |
5897 | scev_reset (); | |
5898 | ||
5899 | finish: | |
5900 | free_loop_data (data); | |
5901 | ||
5902 | return changed; | |
5903 | } | |
5904 | ||
5905 | /* Main entry point. Optimizes induction variables in LOOPS. */ | |
5906 | ||
5907 | void | |
5908 | tree_ssa_iv_optimize (struct loops *loops) | |
5909 | { | |
5910 | struct loop *loop; | |
5911 | struct ivopts_data data; | |
5912 | ||
5913 | tree_ssa_iv_optimize_init (loops, &data); | |
5914 | ||
5915 | /* Optimize the loops starting with the innermost ones. */ | |
5916 | loop = loops->tree_root; | |
5917 | while (loop->inner) | |
5918 | loop = loop->inner; | |
5919 | ||
8b11a64c ZD |
5920 | /* Scan the loops, inner ones first. */ |
5921 | while (loop != loops->tree_root) | |
5922 | { | |
8679c649 JH |
5923 | if (dump_file && (dump_flags & TDF_DETAILS)) |
5924 | flow_loop_dump (loop, dump_file, NULL, 1); | |
e9472263 ZD |
5925 | |
5926 | tree_ssa_iv_optimize_loop (&data, loop); | |
8b11a64c ZD |
5927 | |
5928 | if (loop->next) | |
5929 | { | |
5930 | loop = loop->next; | |
5931 | while (loop->inner) | |
5932 | loop = loop->inner; | |
5933 | } | |
5934 | else | |
5935 | loop = loop->outer; | |
5936 | } | |
5937 | ||
0bca51f0 DN |
5938 | /* FIXME. IV opts introduces new aliases and call-clobbered |
5939 | variables, which need to be renamed. However, when we call the | |
5940 | renamer, not all statements will be scanned for operands. In | |
5941 | particular, the newly introduced aliases may appear in statements | |
5942 | that are considered "unmodified", so the renamer will not get a | |
5943 | chance to rename those operands. | |
5944 | ||
5945 | Work around this problem by forcing an operand re-scan on every | |
5946 | statement. This will not be necessary once the new operand | |
5947 | scanner is implemented. */ | |
5948 | if (need_ssa_update_p ()) | |
5949 | { | |
5950 | basic_block bb; | |
5951 | block_stmt_iterator si; | |
5952 | FOR_EACH_BB (bb) | |
5953 | for (si = bsi_start (bb); !bsi_end_p (si); bsi_next (&si)) | |
5954 | update_stmt (bsi_stmt (si)); | |
0bca51f0 | 5955 | } |
e9472263 | 5956 | |
84d65814 | 5957 | rewrite_into_loop_closed_ssa (NULL, TODO_update_ssa); |
8b11a64c ZD |
5958 | tree_ssa_iv_optimize_finalize (loops, &data); |
5959 | } |