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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 | |
366ccddb KC |
18 | Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA |
19 | 02110-1301, USA. */ | |
8b11a64c ZD |
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 | ||
8b11a64c ZD |
124 | /* Types of uses. */ |
125 | enum use_type | |
126 | { | |
127 | USE_NONLINEAR_EXPR, /* Use in a nonlinear expression. */ | |
8b11a64c ZD |
128 | USE_ADDRESS, /* Use in an address. */ |
129 | USE_COMPARE /* Use is a compare. */ | |
130 | }; | |
131 | ||
132 | /* The candidate - cost pair. */ | |
133 | struct cost_pair | |
134 | { | |
135 | struct iv_cand *cand; /* The candidate. */ | |
136 | unsigned cost; /* The cost. */ | |
137 | bitmap depends_on; /* The list of invariants that have to be | |
138 | preserved. */ | |
f5f12961 ZD |
139 | tree value; /* For final value elimination, the expression for |
140 | the final value of the iv. For iv elimination, | |
141 | the new bound to compare with. */ | |
8b11a64c ZD |
142 | }; |
143 | ||
144 | /* Use. */ | |
145 | struct iv_use | |
146 | { | |
147 | unsigned id; /* The id of the use. */ | |
148 | enum use_type type; /* Type of the use. */ | |
149 | struct iv *iv; /* The induction variable it is based on. */ | |
150 | tree stmt; /* Statement in that it occurs. */ | |
151 | tree *op_p; /* The place where it occurs. */ | |
b1b02be2 ZD |
152 | bitmap related_cands; /* The set of "related" iv candidates, plus the common |
153 | important ones. */ | |
8b11a64c ZD |
154 | |
155 | unsigned n_map_members; /* Number of candidates in the cost_map list. */ | |
156 | struct cost_pair *cost_map; | |
157 | /* The costs wrto the iv candidates. */ | |
158 | ||
159 | struct iv_cand *selected; | |
160 | /* The selected candidate. */ | |
161 | }; | |
162 | ||
163 | /* The position where the iv is computed. */ | |
164 | enum iv_position | |
165 | { | |
166 | IP_NORMAL, /* At the end, just before the exit condition. */ | |
167 | IP_END, /* At the end of the latch block. */ | |
168 | IP_ORIGINAL /* The original biv. */ | |
169 | }; | |
170 | ||
171 | /* The induction variable candidate. */ | |
172 | struct iv_cand | |
173 | { | |
174 | unsigned id; /* The number of the candidate. */ | |
175 | bool important; /* Whether this is an "important" candidate, i.e. such | |
176 | that it should be considered by all uses. */ | |
177 | enum iv_position pos; /* Where it is computed. */ | |
178 | tree incremented_at; /* For original biv, the statement where it is | |
179 | incremented. */ | |
180 | tree var_before; /* The variable used for it before increment. */ | |
181 | tree var_after; /* The variable used for it after increment. */ | |
182 | struct iv *iv; /* The value of the candidate. NULL for | |
183 | "pseudocandidate" used to indicate the possibility | |
184 | to replace the final value of an iv by direct | |
185 | computation of the value. */ | |
186 | unsigned cost; /* Cost of the candidate. */ | |
9be872b7 ZD |
187 | bitmap depends_on; /* The list of invariants that are used in step of the |
188 | biv. */ | |
8b11a64c ZD |
189 | }; |
190 | ||
191 | /* The data used by the induction variable optimizations. */ | |
192 | ||
69ebd99d KH |
193 | typedef struct iv_use *iv_use_p; |
194 | DEF_VEC_P(iv_use_p); | |
195 | DEF_VEC_ALLOC_P(iv_use_p,heap); | |
196 | ||
197 | typedef struct iv_cand *iv_cand_p; | |
198 | DEF_VEC_P(iv_cand_p); | |
199 | DEF_VEC_ALLOC_P(iv_cand_p,heap); | |
200 | ||
8b11a64c ZD |
201 | struct ivopts_data |
202 | { | |
203 | /* The currently optimized loop. */ | |
204 | struct loop *current_loop; | |
205 | ||
9a2ef6b8 ZD |
206 | /* Number of registers used in it. */ |
207 | unsigned regs_used; | |
208 | ||
ca4c3169 ZD |
209 | /* Numbers of iterations for all exits of the current loop. */ |
210 | htab_t niters; | |
211 | ||
8b11a64c ZD |
212 | /* The size of version_info array allocated. */ |
213 | unsigned version_info_size; | |
214 | ||
215 | /* The array of information for the ssa names. */ | |
216 | struct version_info *version_info; | |
217 | ||
218 | /* The bitmap of indices in version_info whose value was changed. */ | |
219 | bitmap relevant; | |
220 | ||
221 | /* The maximum invariant id. */ | |
222 | unsigned max_inv_id; | |
223 | ||
224 | /* The uses of induction variables. */ | |
69ebd99d | 225 | VEC(iv_use_p,heap) *iv_uses; |
8b11a64c ZD |
226 | |
227 | /* The candidates. */ | |
69ebd99d | 228 | VEC(iv_cand_p,heap) *iv_candidates; |
8b11a64c | 229 | |
80cad5fa ZD |
230 | /* A bitmap of important candidates. */ |
231 | bitmap important_candidates; | |
232 | ||
8b11a64c ZD |
233 | /* Whether to consider just related and important candidates when replacing a |
234 | use. */ | |
235 | bool consider_all_candidates; | |
236 | }; | |
237 | ||
b1b02be2 ZD |
238 | /* An assignment of iv candidates to uses. */ |
239 | ||
240 | struct iv_ca | |
241 | { | |
242 | /* The number of uses covered by the assignment. */ | |
243 | unsigned upto; | |
244 | ||
245 | /* Number of uses that cannot be expressed by the candidates in the set. */ | |
246 | unsigned bad_uses; | |
247 | ||
248 | /* Candidate assigned to a use, together with the related costs. */ | |
249 | struct cost_pair **cand_for_use; | |
250 | ||
251 | /* Number of times each candidate is used. */ | |
252 | unsigned *n_cand_uses; | |
253 | ||
254 | /* The candidates used. */ | |
255 | bitmap cands; | |
256 | ||
36f5ada1 ZD |
257 | /* The number of candidates in the set. */ |
258 | unsigned n_cands; | |
259 | ||
b1b02be2 ZD |
260 | /* Total number of registers needed. */ |
261 | unsigned n_regs; | |
262 | ||
263 | /* Total cost of expressing uses. */ | |
264 | unsigned cand_use_cost; | |
265 | ||
266 | /* Total cost of candidates. */ | |
267 | unsigned cand_cost; | |
268 | ||
269 | /* Number of times each invariant is used. */ | |
270 | unsigned *n_invariant_uses; | |
271 | ||
272 | /* Total cost of the assignment. */ | |
273 | unsigned cost; | |
274 | }; | |
275 | ||
276 | /* Difference of two iv candidate assignments. */ | |
277 | ||
278 | struct iv_ca_delta | |
279 | { | |
280 | /* Changed use. */ | |
281 | struct iv_use *use; | |
282 | ||
283 | /* An old assignment (for rollback purposes). */ | |
284 | struct cost_pair *old_cp; | |
285 | ||
286 | /* A new assignment. */ | |
287 | struct cost_pair *new_cp; | |
288 | ||
289 | /* Next change in the list. */ | |
290 | struct iv_ca_delta *next_change; | |
291 | }; | |
292 | ||
8b11a64c ZD |
293 | /* Bound on number of candidates below that all candidates are considered. */ |
294 | ||
295 | #define CONSIDER_ALL_CANDIDATES_BOUND \ | |
296 | ((unsigned) PARAM_VALUE (PARAM_IV_CONSIDER_ALL_CANDIDATES_BOUND)) | |
297 | ||
2a7e31df | 298 | /* If there are more iv occurrences, we just give up (it is quite unlikely that |
8b11a64c ZD |
299 | optimizing such a loop would help, and it would take ages). */ |
300 | ||
301 | #define MAX_CONSIDERED_USES \ | |
302 | ((unsigned) PARAM_VALUE (PARAM_IV_MAX_CONSIDERED_USES)) | |
303 | ||
36f5ada1 ZD |
304 | /* If there are at most this number of ivs in the set, try removing unnecessary |
305 | ivs from the set always. */ | |
306 | ||
307 | #define ALWAYS_PRUNE_CAND_SET_BOUND \ | |
308 | ((unsigned) PARAM_VALUE (PARAM_IV_ALWAYS_PRUNE_CAND_SET_BOUND)) | |
309 | ||
8b11a64c ZD |
310 | /* The list of trees for that the decl_rtl field must be reset is stored |
311 | here. */ | |
312 | ||
69ebd99d | 313 | static VEC(tree,heap) *decl_rtl_to_reset; |
8b11a64c ZD |
314 | |
315 | /* Number of uses recorded in DATA. */ | |
316 | ||
317 | static inline unsigned | |
318 | n_iv_uses (struct ivopts_data *data) | |
319 | { | |
69ebd99d | 320 | return VEC_length (iv_use_p, data->iv_uses); |
8b11a64c ZD |
321 | } |
322 | ||
323 | /* Ith use recorded in DATA. */ | |
324 | ||
325 | static inline struct iv_use * | |
326 | iv_use (struct ivopts_data *data, unsigned i) | |
327 | { | |
69ebd99d | 328 | return VEC_index (iv_use_p, data->iv_uses, i); |
8b11a64c ZD |
329 | } |
330 | ||
331 | /* Number of candidates recorded in DATA. */ | |
332 | ||
333 | static inline unsigned | |
334 | n_iv_cands (struct ivopts_data *data) | |
335 | { | |
69ebd99d | 336 | return VEC_length (iv_cand_p, data->iv_candidates); |
8b11a64c ZD |
337 | } |
338 | ||
339 | /* Ith candidate recorded in DATA. */ | |
340 | ||
341 | static inline struct iv_cand * | |
342 | iv_cand (struct ivopts_data *data, unsigned i) | |
343 | { | |
69ebd99d | 344 | return VEC_index (iv_cand_p, data->iv_candidates, i); |
8b11a64c ZD |
345 | } |
346 | ||
8b11a64c ZD |
347 | /* The single loop exit if it dominates the latch, NULL otherwise. */ |
348 | ||
b7eae7b8 | 349 | edge |
8b11a64c ZD |
350 | single_dom_exit (struct loop *loop) |
351 | { | |
352 | edge exit = loop->single_exit; | |
353 | ||
354 | if (!exit) | |
355 | return NULL; | |
356 | ||
357 | if (!just_once_each_iteration_p (loop, exit->src)) | |
358 | return NULL; | |
359 | ||
360 | return exit; | |
361 | } | |
362 | ||
363 | /* Dumps information about the induction variable IV to FILE. */ | |
364 | ||
365 | extern void dump_iv (FILE *, struct iv *); | |
366 | void | |
367 | dump_iv (FILE *file, struct iv *iv) | |
368 | { | |
e6845c23 ZD |
369 | if (iv->ssa_name) |
370 | { | |
371 | fprintf (file, "ssa name "); | |
372 | print_generic_expr (file, iv->ssa_name, TDF_SLIM); | |
373 | fprintf (file, "\n"); | |
374 | } | |
8b11a64c | 375 | |
2f4675b4 ZD |
376 | fprintf (file, " type "); |
377 | print_generic_expr (file, TREE_TYPE (iv->base), TDF_SLIM); | |
378 | fprintf (file, "\n"); | |
379 | ||
8b11a64c ZD |
380 | if (iv->step) |
381 | { | |
382 | fprintf (file, " base "); | |
383 | print_generic_expr (file, iv->base, TDF_SLIM); | |
384 | fprintf (file, "\n"); | |
385 | ||
386 | fprintf (file, " step "); | |
387 | print_generic_expr (file, iv->step, TDF_SLIM); | |
388 | fprintf (file, "\n"); | |
389 | } | |
390 | else | |
391 | { | |
392 | fprintf (file, " invariant "); | |
393 | print_generic_expr (file, iv->base, TDF_SLIM); | |
394 | fprintf (file, "\n"); | |
395 | } | |
396 | ||
e6845c23 ZD |
397 | if (iv->base_object) |
398 | { | |
399 | fprintf (file, " base object "); | |
400 | print_generic_expr (file, iv->base_object, TDF_SLIM); | |
401 | fprintf (file, "\n"); | |
402 | } | |
403 | ||
8b11a64c ZD |
404 | if (iv->biv_p) |
405 | fprintf (file, " is a biv\n"); | |
406 | } | |
407 | ||
408 | /* Dumps information about the USE to FILE. */ | |
409 | ||
410 | extern void dump_use (FILE *, struct iv_use *); | |
411 | void | |
412 | dump_use (FILE *file, struct iv_use *use) | |
413 | { | |
8b11a64c ZD |
414 | fprintf (file, "use %d\n", use->id); |
415 | ||
416 | switch (use->type) | |
417 | { | |
418 | case USE_NONLINEAR_EXPR: | |
419 | fprintf (file, " generic\n"); | |
420 | break; | |
421 | ||
8b11a64c ZD |
422 | case USE_ADDRESS: |
423 | fprintf (file, " address\n"); | |
424 | break; | |
425 | ||
426 | case USE_COMPARE: | |
427 | fprintf (file, " compare\n"); | |
428 | break; | |
429 | ||
430 | default: | |
1e128c5f | 431 | gcc_unreachable (); |
8b11a64c ZD |
432 | } |
433 | ||
2f4675b4 ZD |
434 | fprintf (file, " in statement "); |
435 | print_generic_expr (file, use->stmt, TDF_SLIM); | |
436 | fprintf (file, "\n"); | |
437 | ||
438 | fprintf (file, " at position "); | |
439 | if (use->op_p) | |
440 | print_generic_expr (file, *use->op_p, TDF_SLIM); | |
441 | fprintf (file, "\n"); | |
442 | ||
e6845c23 | 443 | dump_iv (file, use->iv); |
2f4675b4 | 444 | |
eec5fec9 ZD |
445 | if (use->related_cands) |
446 | { | |
447 | fprintf (file, " related candidates "); | |
448 | dump_bitmap (file, use->related_cands); | |
449 | } | |
8b11a64c ZD |
450 | } |
451 | ||
452 | /* Dumps information about the uses to FILE. */ | |
453 | ||
454 | extern void dump_uses (FILE *, struct ivopts_data *); | |
455 | void | |
456 | dump_uses (FILE *file, struct ivopts_data *data) | |
457 | { | |
458 | unsigned i; | |
459 | struct iv_use *use; | |
460 | ||
461 | for (i = 0; i < n_iv_uses (data); i++) | |
462 | { | |
463 | use = iv_use (data, i); | |
464 | ||
465 | dump_use (file, use); | |
466 | fprintf (file, "\n"); | |
467 | } | |
468 | } | |
469 | ||
470 | /* Dumps information about induction variable candidate CAND to FILE. */ | |
471 | ||
472 | extern void dump_cand (FILE *, struct iv_cand *); | |
473 | void | |
474 | dump_cand (FILE *file, struct iv_cand *cand) | |
475 | { | |
476 | struct iv *iv = cand->iv; | |
477 | ||
478 | fprintf (file, "candidate %d%s\n", | |
479 | cand->id, cand->important ? " (important)" : ""); | |
480 | ||
9be872b7 ZD |
481 | if (cand->depends_on) |
482 | { | |
483 | fprintf (file, " depends on "); | |
484 | dump_bitmap (file, cand->depends_on); | |
485 | } | |
486 | ||
8b11a64c ZD |
487 | if (!iv) |
488 | { | |
489 | fprintf (file, " final value replacement\n"); | |
490 | return; | |
491 | } | |
492 | ||
493 | switch (cand->pos) | |
494 | { | |
495 | case IP_NORMAL: | |
496 | fprintf (file, " incremented before exit test\n"); | |
497 | break; | |
498 | ||
499 | case IP_END: | |
500 | fprintf (file, " incremented at end\n"); | |
501 | break; | |
502 | ||
503 | case IP_ORIGINAL: | |
504 | fprintf (file, " original biv\n"); | |
505 | break; | |
506 | } | |
507 | ||
e6845c23 | 508 | dump_iv (file, iv); |
8b11a64c ZD |
509 | } |
510 | ||
511 | /* Returns the info for ssa version VER. */ | |
512 | ||
513 | static inline struct version_info * | |
514 | ver_info (struct ivopts_data *data, unsigned ver) | |
515 | { | |
516 | return data->version_info + ver; | |
517 | } | |
518 | ||
519 | /* Returns the info for ssa name NAME. */ | |
520 | ||
521 | static inline struct version_info * | |
522 | name_info (struct ivopts_data *data, tree name) | |
523 | { | |
524 | return ver_info (data, SSA_NAME_VERSION (name)); | |
525 | } | |
526 | ||
527 | /* Checks whether there exists number X such that X * B = A, counting modulo | |
528 | 2^BITS. */ | |
529 | ||
530 | static bool | |
531 | divide (unsigned bits, unsigned HOST_WIDE_INT a, unsigned HOST_WIDE_INT b, | |
532 | HOST_WIDE_INT *x) | |
533 | { | |
534 | unsigned HOST_WIDE_INT mask = ~(~(unsigned HOST_WIDE_INT) 0 << (bits - 1) << 1); | |
535 | unsigned HOST_WIDE_INT inv, ex, val; | |
536 | unsigned i; | |
537 | ||
538 | a &= mask; | |
539 | b &= mask; | |
540 | ||
541 | /* First divide the whole equation by 2 as long as possible. */ | |
542 | while (!(a & 1) && !(b & 1)) | |
543 | { | |
544 | a >>= 1; | |
545 | b >>= 1; | |
546 | bits--; | |
547 | mask >>= 1; | |
548 | } | |
549 | ||
550 | if (!(b & 1)) | |
551 | { | |
552 | /* If b is still even, a is odd and there is no such x. */ | |
553 | return false; | |
554 | } | |
555 | ||
556 | /* Find the inverse of b. We compute it as | |
557 | b^(2^(bits - 1) - 1) (mod 2^bits). */ | |
558 | inv = 1; | |
559 | ex = b; | |
560 | for (i = 0; i < bits - 1; i++) | |
561 | { | |
562 | inv = (inv * ex) & mask; | |
563 | ex = (ex * ex) & mask; | |
564 | } | |
565 | ||
566 | val = (a * inv) & mask; | |
567 | ||
1e128c5f | 568 | gcc_assert (((val * b) & mask) == a); |
8b11a64c ZD |
569 | |
570 | if ((val >> (bits - 1)) & 1) | |
571 | val |= ~mask; | |
572 | ||
573 | *x = val; | |
574 | ||
575 | return true; | |
576 | } | |
577 | ||
578 | /* Returns true if STMT is after the place where the IP_NORMAL ivs will be | |
579 | emitted in LOOP. */ | |
580 | ||
581 | static bool | |
582 | stmt_after_ip_normal_pos (struct loop *loop, tree stmt) | |
583 | { | |
584 | basic_block bb = ip_normal_pos (loop), sbb = bb_for_stmt (stmt); | |
585 | ||
1e128c5f | 586 | gcc_assert (bb); |
8b11a64c ZD |
587 | |
588 | if (sbb == loop->latch) | |
589 | return true; | |
590 | ||
591 | if (sbb != bb) | |
592 | return false; | |
593 | ||
594 | return stmt == last_stmt (bb); | |
595 | } | |
596 | ||
597 | /* Returns true if STMT if after the place where the original induction | |
598 | variable CAND is incremented. */ | |
599 | ||
600 | static bool | |
601 | stmt_after_ip_original_pos (struct iv_cand *cand, tree stmt) | |
602 | { | |
603 | basic_block cand_bb = bb_for_stmt (cand->incremented_at); | |
604 | basic_block stmt_bb = bb_for_stmt (stmt); | |
605 | block_stmt_iterator bsi; | |
606 | ||
607 | if (!dominated_by_p (CDI_DOMINATORS, stmt_bb, cand_bb)) | |
608 | return false; | |
609 | ||
610 | if (stmt_bb != cand_bb) | |
611 | return true; | |
612 | ||
613 | /* Scan the block from the end, since the original ivs are usually | |
614 | incremented at the end of the loop body. */ | |
615 | for (bsi = bsi_last (stmt_bb); ; bsi_prev (&bsi)) | |
616 | { | |
617 | if (bsi_stmt (bsi) == cand->incremented_at) | |
618 | return false; | |
619 | if (bsi_stmt (bsi) == stmt) | |
620 | return true; | |
621 | } | |
622 | } | |
623 | ||
624 | /* Returns true if STMT if after the place where the induction variable | |
625 | CAND is incremented in LOOP. */ | |
626 | ||
627 | static bool | |
628 | stmt_after_increment (struct loop *loop, struct iv_cand *cand, tree stmt) | |
629 | { | |
630 | switch (cand->pos) | |
631 | { | |
632 | case IP_END: | |
633 | return false; | |
634 | ||
635 | case IP_NORMAL: | |
636 | return stmt_after_ip_normal_pos (loop, stmt); | |
637 | ||
638 | case IP_ORIGINAL: | |
639 | return stmt_after_ip_original_pos (cand, stmt); | |
640 | ||
641 | default: | |
1e128c5f | 642 | gcc_unreachable (); |
8b11a64c ZD |
643 | } |
644 | } | |
645 | ||
dcccd88d ZD |
646 | /* Returns true if EXP is a ssa name that occurs in an abnormal phi node. */ |
647 | ||
648 | static bool | |
649 | abnormal_ssa_name_p (tree exp) | |
650 | { | |
651 | if (!exp) | |
652 | return false; | |
653 | ||
654 | if (TREE_CODE (exp) != SSA_NAME) | |
655 | return false; | |
656 | ||
657 | return SSA_NAME_OCCURS_IN_ABNORMAL_PHI (exp) != 0; | |
658 | } | |
659 | ||
660 | /* Returns false if BASE or INDEX contains a ssa name that occurs in an | |
661 | abnormal phi node. Callback for for_each_index. */ | |
662 | ||
663 | static bool | |
664 | idx_contains_abnormal_ssa_name_p (tree base, tree *index, | |
665 | void *data ATTRIBUTE_UNUSED) | |
666 | { | |
667 | if (TREE_CODE (base) == ARRAY_REF) | |
668 | { | |
669 | if (abnormal_ssa_name_p (TREE_OPERAND (base, 2))) | |
670 | return false; | |
671 | if (abnormal_ssa_name_p (TREE_OPERAND (base, 3))) | |
672 | return false; | |
673 | } | |
674 | ||
675 | return !abnormal_ssa_name_p (*index); | |
676 | } | |
677 | ||
678 | /* Returns true if EXPR contains a ssa name that occurs in an | |
679 | abnormal phi node. */ | |
680 | ||
681 | static bool | |
682 | contains_abnormal_ssa_name_p (tree expr) | |
683 | { | |
684 | enum tree_code code; | |
685 | enum tree_code_class class; | |
686 | ||
687 | if (!expr) | |
688 | return false; | |
689 | ||
690 | code = TREE_CODE (expr); | |
691 | class = TREE_CODE_CLASS (code); | |
692 | ||
693 | if (code == SSA_NAME) | |
694 | return SSA_NAME_OCCURS_IN_ABNORMAL_PHI (expr) != 0; | |
695 | ||
696 | if (code == INTEGER_CST | |
697 | || is_gimple_min_invariant (expr)) | |
698 | return false; | |
699 | ||
700 | if (code == ADDR_EXPR) | |
701 | return !for_each_index (&TREE_OPERAND (expr, 0), | |
702 | idx_contains_abnormal_ssa_name_p, | |
703 | NULL); | |
704 | ||
705 | switch (class) | |
706 | { | |
707 | case tcc_binary: | |
708 | case tcc_comparison: | |
709 | if (contains_abnormal_ssa_name_p (TREE_OPERAND (expr, 1))) | |
710 | return true; | |
711 | ||
712 | /* Fallthru. */ | |
713 | case tcc_unary: | |
714 | if (contains_abnormal_ssa_name_p (TREE_OPERAND (expr, 0))) | |
715 | return true; | |
716 | ||
717 | break; | |
718 | ||
719 | default: | |
720 | gcc_unreachable (); | |
721 | } | |
722 | ||
723 | return false; | |
724 | } | |
725 | ||
ca4c3169 ZD |
726 | /* Element of the table in that we cache the numbers of iterations obtained |
727 | from exits of the loop. */ | |
728 | ||
729 | struct nfe_cache_elt | |
730 | { | |
731 | /* The edge for that the number of iterations is cached. */ | |
732 | edge exit; | |
733 | ||
dcccd88d ZD |
734 | /* Number of iterations corresponding to this exit, or NULL if it cannot be |
735 | determined. */ | |
736 | tree niter; | |
ca4c3169 ZD |
737 | }; |
738 | ||
739 | /* Hash function for nfe_cache_elt E. */ | |
740 | ||
741 | static hashval_t | |
742 | nfe_hash (const void *e) | |
743 | { | |
744 | const struct nfe_cache_elt *elt = e; | |
745 | ||
746 | return htab_hash_pointer (elt->exit); | |
747 | } | |
748 | ||
749 | /* Equality function for nfe_cache_elt E1 and edge E2. */ | |
750 | ||
751 | static int | |
752 | nfe_eq (const void *e1, const void *e2) | |
753 | { | |
754 | const struct nfe_cache_elt *elt1 = e1; | |
755 | ||
756 | return elt1->exit == e2; | |
757 | } | |
758 | ||
dcccd88d | 759 | /* Returns tree describing number of iterations determined from |
ca4c3169 ZD |
760 | EXIT of DATA->current_loop, or NULL if something goes wrong. */ |
761 | ||
dcccd88d | 762 | static tree |
ca4c3169 ZD |
763 | niter_for_exit (struct ivopts_data *data, edge exit) |
764 | { | |
765 | struct nfe_cache_elt *nfe_desc; | |
dcccd88d | 766 | struct tree_niter_desc desc; |
ca4c3169 ZD |
767 | PTR *slot; |
768 | ||
769 | slot = htab_find_slot_with_hash (data->niters, exit, | |
770 | htab_hash_pointer (exit), | |
771 | INSERT); | |
772 | ||
773 | if (!*slot) | |
774 | { | |
775 | nfe_desc = xmalloc (sizeof (struct nfe_cache_elt)); | |
776 | nfe_desc->exit = exit; | |
dcccd88d ZD |
777 | |
778 | /* Try to determine number of iterations. We must know it | |
779 | unconditionally (i.e., without possibility of # of iterations | |
780 | being zero). Also, we cannot safely work with ssa names that | |
781 | appear in phi nodes on abnormal edges, so that we do not create | |
782 | overlapping life ranges for them (PR 27283). */ | |
783 | if (number_of_iterations_exit (data->current_loop, | |
784 | exit, &desc, true) | |
785 | && zero_p (desc.may_be_zero) | |
786 | && !contains_abnormal_ssa_name_p (desc.niter)) | |
787 | nfe_desc->niter = desc.niter; | |
788 | else | |
789 | nfe_desc->niter = NULL_TREE; | |
ca4c3169 ZD |
790 | } |
791 | else | |
792 | nfe_desc = *slot; | |
793 | ||
dcccd88d | 794 | return nfe_desc->niter; |
ca4c3169 ZD |
795 | } |
796 | ||
dcccd88d | 797 | /* Returns tree describing number of iterations determined from |
ca4c3169 ZD |
798 | single dominating exit of DATA->current_loop, or NULL if something |
799 | goes wrong. */ | |
800 | ||
dcccd88d | 801 | static tree |
ca4c3169 ZD |
802 | niter_for_single_dom_exit (struct ivopts_data *data) |
803 | { | |
804 | edge exit = single_dom_exit (data->current_loop); | |
805 | ||
806 | if (!exit) | |
807 | return NULL; | |
808 | ||
809 | return niter_for_exit (data, exit); | |
810 | } | |
811 | ||
8b11a64c | 812 | /* Initializes data structures used by the iv optimization pass, stored |
9a2ef6b8 | 813 | in DATA. */ |
8b11a64c ZD |
814 | |
815 | static void | |
9a2ef6b8 | 816 | tree_ssa_iv_optimize_init (struct ivopts_data *data) |
8b11a64c | 817 | { |
8b11a64c | 818 | data->version_info_size = 2 * num_ssa_names; |
5ed6ace5 | 819 | data->version_info = XCNEWVEC (struct version_info, data->version_info_size); |
8bdbfff5 NS |
820 | data->relevant = BITMAP_ALLOC (NULL); |
821 | data->important_candidates = BITMAP_ALLOC (NULL); | |
8b11a64c | 822 | data->max_inv_id = 0; |
ca4c3169 | 823 | data->niters = htab_create (10, nfe_hash, nfe_eq, free); |
69ebd99d KH |
824 | data->iv_uses = VEC_alloc (iv_use_p, heap, 20); |
825 | data->iv_candidates = VEC_alloc (iv_cand_p, heap, 20); | |
826 | decl_rtl_to_reset = VEC_alloc (tree, heap, 20); | |
8b11a64c ZD |
827 | } |
828 | ||
e6845c23 ZD |
829 | /* Returns a memory object to that EXPR points. In case we are able to |
830 | determine that it does not point to any such object, NULL is returned. */ | |
831 | ||
832 | static tree | |
833 | determine_base_object (tree expr) | |
834 | { | |
835 | enum tree_code code = TREE_CODE (expr); | |
836 | tree base, obj, op0, op1; | |
837 | ||
838 | if (!POINTER_TYPE_P (TREE_TYPE (expr))) | |
839 | return NULL_TREE; | |
840 | ||
841 | switch (code) | |
842 | { | |
843 | case INTEGER_CST: | |
844 | return NULL_TREE; | |
845 | ||
846 | case ADDR_EXPR: | |
847 | obj = TREE_OPERAND (expr, 0); | |
848 | base = get_base_address (obj); | |
849 | ||
850 | if (!base) | |
f5e2738c | 851 | return expr; |
e6845c23 | 852 | |
7299dbfb | 853 | if (TREE_CODE (base) == INDIRECT_REF) |
f5e2738c | 854 | return determine_base_object (TREE_OPERAND (base, 0)); |
7299dbfb | 855 | |
62b37d91 RG |
856 | return fold_convert (ptr_type_node, |
857 | build_fold_addr_expr (base)); | |
e6845c23 ZD |
858 | |
859 | case PLUS_EXPR: | |
860 | case MINUS_EXPR: | |
861 | op0 = determine_base_object (TREE_OPERAND (expr, 0)); | |
862 | op1 = determine_base_object (TREE_OPERAND (expr, 1)); | |
863 | ||
864 | if (!op1) | |
865 | return op0; | |
866 | ||
867 | if (!op0) | |
868 | return (code == PLUS_EXPR | |
869 | ? op1 | |
62b37d91 | 870 | : fold_build1 (NEGATE_EXPR, ptr_type_node, op1)); |
e6845c23 | 871 | |
62b37d91 | 872 | return fold_build2 (code, ptr_type_node, op0, op1); |
e6845c23 | 873 | |
f5e2738c ZD |
874 | case NOP_EXPR: |
875 | case CONVERT_EXPR: | |
876 | return determine_base_object (TREE_OPERAND (expr, 0)); | |
877 | ||
e6845c23 ZD |
878 | default: |
879 | return fold_convert (ptr_type_node, expr); | |
880 | } | |
881 | } | |
882 | ||
8b11a64c ZD |
883 | /* Allocates an induction variable with given initial value BASE and step STEP |
884 | for loop LOOP. */ | |
885 | ||
886 | static struct iv * | |
887 | alloc_iv (tree base, tree step) | |
888 | { | |
5ed6ace5 | 889 | struct iv *iv = XCNEW (struct iv); |
8b11a64c ZD |
890 | |
891 | if (step && integer_zerop (step)) | |
892 | step = NULL_TREE; | |
893 | ||
894 | iv->base = base; | |
e6845c23 | 895 | iv->base_object = determine_base_object (base); |
8b11a64c ZD |
896 | iv->step = step; |
897 | iv->biv_p = false; | |
898 | iv->have_use_for = false; | |
899 | iv->use_id = 0; | |
900 | iv->ssa_name = NULL_TREE; | |
901 | ||
902 | return iv; | |
903 | } | |
904 | ||
905 | /* Sets STEP and BASE for induction variable IV. */ | |
906 | ||
907 | static void | |
908 | set_iv (struct ivopts_data *data, tree iv, tree base, tree step) | |
909 | { | |
910 | struct version_info *info = name_info (data, iv); | |
911 | ||
1e128c5f | 912 | gcc_assert (!info->iv); |
8b11a64c ZD |
913 | |
914 | bitmap_set_bit (data->relevant, SSA_NAME_VERSION (iv)); | |
915 | info->iv = alloc_iv (base, step); | |
916 | info->iv->ssa_name = iv; | |
917 | } | |
918 | ||
919 | /* Finds induction variable declaration for VAR. */ | |
920 | ||
921 | static struct iv * | |
922 | get_iv (struct ivopts_data *data, tree var) | |
923 | { | |
924 | basic_block bb; | |
925 | ||
926 | if (!name_info (data, var)->iv) | |
927 | { | |
928 | bb = bb_for_stmt (SSA_NAME_DEF_STMT (var)); | |
929 | ||
930 | if (!bb | |
931 | || !flow_bb_inside_loop_p (data->current_loop, bb)) | |
932 | set_iv (data, var, var, NULL_TREE); | |
933 | } | |
934 | ||
935 | return name_info (data, var)->iv; | |
936 | } | |
937 | ||
9be872b7 ZD |
938 | /* Determines the step of a biv defined in PHI. Returns NULL if PHI does |
939 | not define a simple affine biv with nonzero step. */ | |
8b11a64c ZD |
940 | |
941 | static tree | |
942 | determine_biv_step (tree phi) | |
943 | { | |
944 | struct loop *loop = bb_for_stmt (phi)->loop_father; | |
a6f778b2 ZD |
945 | tree name = PHI_RESULT (phi); |
946 | affine_iv iv; | |
8b11a64c ZD |
947 | |
948 | if (!is_gimple_reg (name)) | |
949 | return NULL_TREE; | |
950 | ||
a6f778b2 | 951 | if (!simple_iv (loop, phi, name, &iv, true)) |
8b11a64c ZD |
952 | return NULL_TREE; |
953 | ||
a6f778b2 | 954 | return (zero_p (iv.step) ? NULL_TREE : iv.step); |
8b11a64c ZD |
955 | } |
956 | ||
8b11a64c ZD |
957 | /* Finds basic ivs. */ |
958 | ||
959 | static bool | |
960 | find_bivs (struct ivopts_data *data) | |
961 | { | |
962 | tree phi, step, type, base; | |
963 | bool found = false; | |
964 | struct loop *loop = data->current_loop; | |
965 | ||
bb29d951 | 966 | for (phi = phi_nodes (loop->header); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
967 | { |
968 | if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (PHI_RESULT (phi))) | |
969 | continue; | |
970 | ||
971 | step = determine_biv_step (phi); | |
8b11a64c ZD |
972 | if (!step) |
973 | continue; | |
8b11a64c ZD |
974 | |
975 | base = PHI_ARG_DEF_FROM_EDGE (phi, loop_preheader_edge (loop)); | |
d7bf3bcf | 976 | base = expand_simple_operations (base); |
9be872b7 ZD |
977 | if (contains_abnormal_ssa_name_p (base) |
978 | || contains_abnormal_ssa_name_p (step)) | |
8b11a64c ZD |
979 | continue; |
980 | ||
981 | type = TREE_TYPE (PHI_RESULT (phi)); | |
982 | base = fold_convert (type, base); | |
9be872b7 ZD |
983 | if (step) |
984 | step = fold_convert (type, step); | |
8b11a64c ZD |
985 | |
986 | set_iv (data, PHI_RESULT (phi), base, step); | |
987 | found = true; | |
988 | } | |
989 | ||
990 | return found; | |
991 | } | |
992 | ||
993 | /* Marks basic ivs. */ | |
994 | ||
995 | static void | |
996 | mark_bivs (struct ivopts_data *data) | |
997 | { | |
998 | tree phi, var; | |
999 | struct iv *iv, *incr_iv; | |
1000 | struct loop *loop = data->current_loop; | |
1001 | basic_block incr_bb; | |
1002 | ||
bb29d951 | 1003 | for (phi = phi_nodes (loop->header); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
1004 | { |
1005 | iv = get_iv (data, PHI_RESULT (phi)); | |
1006 | if (!iv) | |
1007 | continue; | |
1008 | ||
1009 | var = PHI_ARG_DEF_FROM_EDGE (phi, loop_latch_edge (loop)); | |
1010 | incr_iv = get_iv (data, var); | |
1011 | if (!incr_iv) | |
1012 | continue; | |
1013 | ||
1014 | /* If the increment is in the subloop, ignore it. */ | |
1015 | incr_bb = bb_for_stmt (SSA_NAME_DEF_STMT (var)); | |
1016 | if (incr_bb->loop_father != data->current_loop | |
1017 | || (incr_bb->flags & BB_IRREDUCIBLE_LOOP)) | |
1018 | continue; | |
1019 | ||
1020 | iv->biv_p = true; | |
1021 | incr_iv->biv_p = true; | |
1022 | } | |
1023 | } | |
1024 | ||
1025 | /* Checks whether STMT defines a linear induction variable and stores its | |
a6f778b2 | 1026 | parameters to IV. */ |
8b11a64c ZD |
1027 | |
1028 | static bool | |
a6f778b2 | 1029 | find_givs_in_stmt_scev (struct ivopts_data *data, tree stmt, affine_iv *iv) |
8b11a64c ZD |
1030 | { |
1031 | tree lhs; | |
1032 | struct loop *loop = data->current_loop; | |
1033 | ||
a6f778b2 ZD |
1034 | iv->base = NULL_TREE; |
1035 | iv->step = NULL_TREE; | |
8b11a64c ZD |
1036 | |
1037 | if (TREE_CODE (stmt) != MODIFY_EXPR) | |
1038 | return false; | |
1039 | ||
1040 | lhs = TREE_OPERAND (stmt, 0); | |
1041 | if (TREE_CODE (lhs) != SSA_NAME) | |
1042 | return false; | |
1043 | ||
a6f778b2 | 1044 | if (!simple_iv (loop, stmt, TREE_OPERAND (stmt, 1), iv, true)) |
8b11a64c | 1045 | return false; |
a6f778b2 | 1046 | iv->base = expand_simple_operations (iv->base); |
8b11a64c | 1047 | |
a6f778b2 ZD |
1048 | if (contains_abnormal_ssa_name_p (iv->base) |
1049 | || contains_abnormal_ssa_name_p (iv->step)) | |
8b11a64c ZD |
1050 | return false; |
1051 | ||
1052 | return true; | |
1053 | } | |
1054 | ||
1055 | /* Finds general ivs in statement STMT. */ | |
1056 | ||
1057 | static void | |
1058 | find_givs_in_stmt (struct ivopts_data *data, tree stmt) | |
1059 | { | |
a6f778b2 | 1060 | affine_iv iv; |
8b11a64c | 1061 | |
a6f778b2 | 1062 | if (!find_givs_in_stmt_scev (data, stmt, &iv)) |
8b11a64c ZD |
1063 | return; |
1064 | ||
a6f778b2 | 1065 | set_iv (data, TREE_OPERAND (stmt, 0), iv.base, iv.step); |
8b11a64c ZD |
1066 | } |
1067 | ||
1068 | /* Finds general ivs in basic block BB. */ | |
1069 | ||
1070 | static void | |
1071 | find_givs_in_bb (struct ivopts_data *data, basic_block bb) | |
1072 | { | |
1073 | block_stmt_iterator bsi; | |
1074 | ||
1075 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
1076 | find_givs_in_stmt (data, bsi_stmt (bsi)); | |
1077 | } | |
1078 | ||
1079 | /* Finds general ivs. */ | |
1080 | ||
1081 | static void | |
1082 | find_givs (struct ivopts_data *data) | |
1083 | { | |
1084 | struct loop *loop = data->current_loop; | |
1085 | basic_block *body = get_loop_body_in_dom_order (loop); | |
1086 | unsigned i; | |
1087 | ||
1088 | for (i = 0; i < loop->num_nodes; i++) | |
1089 | find_givs_in_bb (data, body[i]); | |
1090 | free (body); | |
1091 | } | |
1092 | ||
8b11a64c ZD |
1093 | /* For each ssa name defined in LOOP determines whether it is an induction |
1094 | variable and if so, its initial value and step. */ | |
1095 | ||
1096 | static bool | |
1097 | find_induction_variables (struct ivopts_data *data) | |
1098 | { | |
1099 | unsigned i; | |
87c476a2 | 1100 | bitmap_iterator bi; |
8b11a64c ZD |
1101 | |
1102 | if (!find_bivs (data)) | |
1103 | return false; | |
1104 | ||
1105 | find_givs (data); | |
1106 | mark_bivs (data); | |
8b11a64c ZD |
1107 | |
1108 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1109 | { | |
dcccd88d | 1110 | tree niter = niter_for_single_dom_exit (data); |
ca4c3169 ZD |
1111 | |
1112 | if (niter) | |
8b11a64c ZD |
1113 | { |
1114 | fprintf (dump_file, " number of iterations "); | |
dcccd88d ZD |
1115 | print_generic_expr (dump_file, niter, TDF_SLIM); |
1116 | fprintf (dump_file, "\n\n"); | |
8b11a64c ZD |
1117 | }; |
1118 | ||
1119 | fprintf (dump_file, "Induction variables:\n\n"); | |
1120 | ||
87c476a2 | 1121 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
8b11a64c ZD |
1122 | { |
1123 | if (ver_info (data, i)->iv) | |
1124 | dump_iv (dump_file, ver_info (data, i)->iv); | |
87c476a2 | 1125 | } |
8b11a64c ZD |
1126 | } |
1127 | ||
1128 | return true; | |
1129 | } | |
1130 | ||
1131 | /* Records a use of type USE_TYPE at *USE_P in STMT whose value is IV. */ | |
1132 | ||
1133 | static struct iv_use * | |
1134 | record_use (struct ivopts_data *data, tree *use_p, struct iv *iv, | |
1135 | tree stmt, enum use_type use_type) | |
1136 | { | |
5ed6ace5 | 1137 | struct iv_use *use = XCNEW (struct iv_use); |
8b11a64c ZD |
1138 | |
1139 | use->id = n_iv_uses (data); | |
1140 | use->type = use_type; | |
1141 | use->iv = iv; | |
1142 | use->stmt = stmt; | |
1143 | use->op_p = use_p; | |
8bdbfff5 | 1144 | use->related_cands = BITMAP_ALLOC (NULL); |
8b11a64c | 1145 | |
e6845c23 ZD |
1146 | /* To avoid showing ssa name in the dumps, if it was not reset by the |
1147 | caller. */ | |
1148 | iv->ssa_name = NULL_TREE; | |
1149 | ||
8b11a64c ZD |
1150 | if (dump_file && (dump_flags & TDF_DETAILS)) |
1151 | dump_use (dump_file, use); | |
1152 | ||
69ebd99d | 1153 | VEC_safe_push (iv_use_p, heap, data->iv_uses, use); |
8b11a64c ZD |
1154 | |
1155 | return use; | |
1156 | } | |
1157 | ||
1158 | /* Checks whether OP is a loop-level invariant and if so, records it. | |
1159 | NONLINEAR_USE is true if the invariant is used in a way we do not | |
1160 | handle specially. */ | |
1161 | ||
1162 | static void | |
1163 | record_invariant (struct ivopts_data *data, tree op, bool nonlinear_use) | |
1164 | { | |
1165 | basic_block bb; | |
1166 | struct version_info *info; | |
1167 | ||
1168 | if (TREE_CODE (op) != SSA_NAME | |
1169 | || !is_gimple_reg (op)) | |
1170 | return; | |
1171 | ||
1172 | bb = bb_for_stmt (SSA_NAME_DEF_STMT (op)); | |
1173 | if (bb | |
1174 | && flow_bb_inside_loop_p (data->current_loop, bb)) | |
1175 | return; | |
1176 | ||
1177 | info = name_info (data, op); | |
1178 | info->name = op; | |
1179 | info->has_nonlin_use |= nonlinear_use; | |
1180 | if (!info->inv_id) | |
1181 | info->inv_id = ++data->max_inv_id; | |
1182 | bitmap_set_bit (data->relevant, SSA_NAME_VERSION (op)); | |
1183 | } | |
1184 | ||
50cc9802 | 1185 | /* Checks whether the use OP is interesting and if so, records it. */ |
8b11a64c ZD |
1186 | |
1187 | static struct iv_use * | |
50cc9802 | 1188 | find_interesting_uses_op (struct ivopts_data *data, tree op) |
8b11a64c ZD |
1189 | { |
1190 | struct iv *iv; | |
1191 | struct iv *civ; | |
1192 | tree stmt; | |
1193 | struct iv_use *use; | |
1194 | ||
1195 | if (TREE_CODE (op) != SSA_NAME) | |
1196 | return NULL; | |
1197 | ||
1198 | iv = get_iv (data, op); | |
1199 | if (!iv) | |
1200 | return NULL; | |
1201 | ||
1202 | if (iv->have_use_for) | |
1203 | { | |
1204 | use = iv_use (data, iv->use_id); | |
1205 | ||
50cc9802 | 1206 | gcc_assert (use->type == USE_NONLINEAR_EXPR); |
8b11a64c ZD |
1207 | return use; |
1208 | } | |
1209 | ||
1210 | if (zero_p (iv->step)) | |
1211 | { | |
1212 | record_invariant (data, op, true); | |
1213 | return NULL; | |
1214 | } | |
1215 | iv->have_use_for = true; | |
1216 | ||
5ed6ace5 | 1217 | civ = XNEW (struct iv); |
8b11a64c ZD |
1218 | *civ = *iv; |
1219 | ||
1220 | stmt = SSA_NAME_DEF_STMT (op); | |
1e128c5f GB |
1221 | gcc_assert (TREE_CODE (stmt) == PHI_NODE |
1222 | || TREE_CODE (stmt) == MODIFY_EXPR); | |
8b11a64c | 1223 | |
50cc9802 | 1224 | use = record_use (data, NULL, civ, stmt, USE_NONLINEAR_EXPR); |
8b11a64c ZD |
1225 | iv->use_id = use->id; |
1226 | ||
1227 | return use; | |
1228 | } | |
1229 | ||
8b11a64c ZD |
1230 | /* Checks whether the condition *COND_P in STMT is interesting |
1231 | and if so, records it. */ | |
1232 | ||
1233 | static void | |
1234 | find_interesting_uses_cond (struct ivopts_data *data, tree stmt, tree *cond_p) | |
1235 | { | |
1236 | tree *op0_p; | |
1237 | tree *op1_p; | |
1238 | struct iv *iv0 = NULL, *iv1 = NULL, *civ; | |
1239 | struct iv const_iv; | |
1240 | tree zero = integer_zero_node; | |
1241 | ||
1242 | const_iv.step = NULL_TREE; | |
1243 | ||
f5f12961 ZD |
1244 | if (TREE_CODE (*cond_p) != SSA_NAME |
1245 | && !COMPARISON_CLASS_P (*cond_p)) | |
8b11a64c ZD |
1246 | return; |
1247 | ||
1248 | if (TREE_CODE (*cond_p) == SSA_NAME) | |
1249 | { | |
1250 | op0_p = cond_p; | |
1251 | op1_p = &zero; | |
1252 | } | |
1253 | else | |
1254 | { | |
1255 | op0_p = &TREE_OPERAND (*cond_p, 0); | |
1256 | op1_p = &TREE_OPERAND (*cond_p, 1); | |
1257 | } | |
1258 | ||
1259 | if (TREE_CODE (*op0_p) == SSA_NAME) | |
1260 | iv0 = get_iv (data, *op0_p); | |
1261 | else | |
1262 | iv0 = &const_iv; | |
1263 | ||
1264 | if (TREE_CODE (*op1_p) == SSA_NAME) | |
1265 | iv1 = get_iv (data, *op1_p); | |
1266 | else | |
1267 | iv1 = &const_iv; | |
1268 | ||
1269 | if (/* When comparing with non-invariant value, we may not do any senseful | |
1270 | induction variable elimination. */ | |
1271 | (!iv0 || !iv1) | |
1272 | /* Eliminating condition based on two ivs would be nontrivial. | |
1273 | ??? TODO -- it is not really important to handle this case. */ | |
1274 | || (!zero_p (iv0->step) && !zero_p (iv1->step))) | |
1275 | { | |
1276 | find_interesting_uses_op (data, *op0_p); | |
1277 | find_interesting_uses_op (data, *op1_p); | |
1278 | return; | |
1279 | } | |
1280 | ||
1281 | if (zero_p (iv0->step) && zero_p (iv1->step)) | |
1282 | { | |
1283 | /* If both are invariants, this is a work for unswitching. */ | |
1284 | return; | |
1285 | } | |
1286 | ||
5ed6ace5 | 1287 | civ = XNEW (struct iv); |
8b11a64c ZD |
1288 | *civ = zero_p (iv0->step) ? *iv1: *iv0; |
1289 | record_use (data, cond_p, civ, stmt, USE_COMPARE); | |
1290 | } | |
1291 | ||
be35cf60 ZD |
1292 | /* Returns true if expression EXPR is obviously invariant in LOOP, |
1293 | i.e. if all its operands are defined outside of the LOOP. */ | |
1294 | ||
feb075f4 | 1295 | bool |
be35cf60 ZD |
1296 | expr_invariant_in_loop_p (struct loop *loop, tree expr) |
1297 | { | |
1298 | basic_block def_bb; | |
1299 | unsigned i, len; | |
1300 | ||
1301 | if (is_gimple_min_invariant (expr)) | |
1302 | return true; | |
1303 | ||
1304 | if (TREE_CODE (expr) == SSA_NAME) | |
1305 | { | |
1306 | def_bb = bb_for_stmt (SSA_NAME_DEF_STMT (expr)); | |
1307 | if (def_bb | |
1308 | && flow_bb_inside_loop_p (loop, def_bb)) | |
1309 | return false; | |
1310 | ||
1311 | return true; | |
1312 | } | |
1313 | ||
1314 | if (!EXPR_P (expr)) | |
1315 | return false; | |
1316 | ||
54e4aedb | 1317 | len = TREE_CODE_LENGTH (TREE_CODE (expr)); |
be35cf60 ZD |
1318 | for (i = 0; i < len; i++) |
1319 | if (!expr_invariant_in_loop_p (loop, TREE_OPERAND (expr, i))) | |
1320 | return false; | |
1321 | ||
1322 | return true; | |
1323 | } | |
1324 | ||
8b11a64c ZD |
1325 | /* Cumulates the steps of indices into DATA and replaces their values with the |
1326 | initial ones. Returns false when the value of the index cannot be determined. | |
1327 | Callback for for_each_index. */ | |
1328 | ||
1329 | struct ifs_ivopts_data | |
1330 | { | |
1331 | struct ivopts_data *ivopts_data; | |
1332 | tree stmt; | |
1333 | tree *step_p; | |
1334 | }; | |
1335 | ||
1336 | static bool | |
1337 | idx_find_step (tree base, tree *idx, void *data) | |
1338 | { | |
1339 | struct ifs_ivopts_data *dta = data; | |
1340 | struct iv *iv; | |
1c1205fb | 1341 | tree step, iv_step, lbound, off; |
2f4675b4 | 1342 | struct loop *loop = dta->ivopts_data->current_loop; |
be35cf60 ZD |
1343 | |
1344 | if (TREE_CODE (base) == MISALIGNED_INDIRECT_REF | |
1345 | || TREE_CODE (base) == ALIGN_INDIRECT_REF) | |
1346 | return false; | |
1347 | ||
1348 | /* If base is a component ref, require that the offset of the reference | |
3a7c155d | 1349 | be invariant. */ |
be35cf60 ZD |
1350 | if (TREE_CODE (base) == COMPONENT_REF) |
1351 | { | |
1352 | off = component_ref_field_offset (base); | |
1353 | return expr_invariant_in_loop_p (loop, off); | |
1354 | } | |
1355 | ||
1356 | /* If base is array, first check whether we will be able to move the | |
1357 | reference out of the loop (in order to take its address in strength | |
1358 | reduction). In order for this to work we need both lower bound | |
1359 | and step to be loop invariants. */ | |
1360 | if (TREE_CODE (base) == ARRAY_REF) | |
1361 | { | |
1362 | step = array_ref_element_size (base); | |
1363 | lbound = array_ref_low_bound (base); | |
1364 | ||
1365 | if (!expr_invariant_in_loop_p (loop, step) | |
1366 | || !expr_invariant_in_loop_p (loop, lbound)) | |
1367 | return false; | |
1368 | } | |
1369 | ||
8b11a64c ZD |
1370 | if (TREE_CODE (*idx) != SSA_NAME) |
1371 | return true; | |
1372 | ||
1373 | iv = get_iv (dta->ivopts_data, *idx); | |
1374 | if (!iv) | |
1375 | return false; | |
1376 | ||
ea643120 RG |
1377 | /* XXX We produce for a base of *D42 with iv->base being &x[0] |
1378 | *&x[0], which is not folded and does not trigger the | |
1379 | ARRAY_REF path below. */ | |
8b11a64c ZD |
1380 | *idx = iv->base; |
1381 | ||
1382 | if (!iv->step) | |
1383 | return true; | |
1384 | ||
8b11a64c | 1385 | if (TREE_CODE (base) == ARRAY_REF) |
2f4675b4 ZD |
1386 | { |
1387 | step = array_ref_element_size (base); | |
2f4675b4 ZD |
1388 | |
1389 | /* We only handle addresses whose step is an integer constant. */ | |
1390 | if (TREE_CODE (step) != INTEGER_CST) | |
1391 | return false; | |
2f4675b4 | 1392 | } |
8b11a64c | 1393 | else |
5212068f | 1394 | /* The step for pointer arithmetics already is 1 byte. */ |
1c1205fb | 1395 | step = build_int_cst (sizetype, 1); |
8b11a64c | 1396 | |
d7770457 SP |
1397 | /* FIXME: convert_step should not be used outside chrec_convert: fix |
1398 | this by calling chrec_convert. */ | |
1e8552eb SP |
1399 | iv_step = convert_step (dta->ivopts_data->current_loop, |
1400 | sizetype, iv->base, iv->step, dta->stmt); | |
8b11a64c ZD |
1401 | |
1402 | if (!iv_step) | |
1403 | { | |
1404 | /* The index might wrap. */ | |
1405 | return false; | |
1406 | } | |
1407 | ||
1c1205fb | 1408 | step = fold_build2 (MULT_EXPR, sizetype, step, iv_step); |
8b11a64c ZD |
1409 | |
1410 | if (!*dta->step_p) | |
1411 | *dta->step_p = step; | |
1412 | else | |
1c1205fb | 1413 | *dta->step_p = fold_build2 (PLUS_EXPR, sizetype, *dta->step_p, step); |
8b11a64c ZD |
1414 | |
1415 | return true; | |
1416 | } | |
1417 | ||
1418 | /* Records use in index IDX. Callback for for_each_index. Ivopts data | |
1419 | object is passed to it in DATA. */ | |
1420 | ||
1421 | static bool | |
2f4675b4 | 1422 | idx_record_use (tree base, tree *idx, |
8b11a64c ZD |
1423 | void *data) |
1424 | { | |
1425 | find_interesting_uses_op (data, *idx); | |
2f4675b4 ZD |
1426 | if (TREE_CODE (base) == ARRAY_REF) |
1427 | { | |
1428 | find_interesting_uses_op (data, array_ref_element_size (base)); | |
1429 | find_interesting_uses_op (data, array_ref_low_bound (base)); | |
1430 | } | |
8b11a64c ZD |
1431 | return true; |
1432 | } | |
1433 | ||
0a915e3d ZD |
1434 | /* Returns true if memory reference REF may be unaligned. */ |
1435 | ||
1436 | static bool | |
1437 | may_be_unaligned_p (tree ref) | |
1438 | { | |
1439 | tree base; | |
1440 | tree base_type; | |
1441 | HOST_WIDE_INT bitsize; | |
1442 | HOST_WIDE_INT bitpos; | |
1443 | tree toffset; | |
1444 | enum machine_mode mode; | |
1445 | int unsignedp, volatilep; | |
1446 | unsigned base_align; | |
1447 | ||
ac182688 | 1448 | /* TARGET_MEM_REFs are translated directly to valid MEMs on the target, |
607fb860 | 1449 | thus they are not misaligned. */ |
ac182688 ZD |
1450 | if (TREE_CODE (ref) == TARGET_MEM_REF) |
1451 | return false; | |
1452 | ||
0a915e3d ZD |
1453 | /* The test below is basically copy of what expr.c:normal_inner_ref |
1454 | does to check whether the object must be loaded by parts when | |
1455 | STRICT_ALIGNMENT is true. */ | |
1456 | base = get_inner_reference (ref, &bitsize, &bitpos, &toffset, &mode, | |
1457 | &unsignedp, &volatilep, true); | |
1458 | base_type = TREE_TYPE (base); | |
1459 | base_align = TYPE_ALIGN (base_type); | |
1460 | ||
1461 | if (mode != BLKmode | |
1462 | && (base_align < GET_MODE_ALIGNMENT (mode) | |
1463 | || bitpos % GET_MODE_ALIGNMENT (mode) != 0 | |
1464 | || bitpos % BITS_PER_UNIT != 0)) | |
1465 | return true; | |
1466 | ||
1467 | return false; | |
1468 | } | |
1469 | ||
8b11a64c ZD |
1470 | /* Finds addresses in *OP_P inside STMT. */ |
1471 | ||
1472 | static void | |
1473 | find_interesting_uses_address (struct ivopts_data *data, tree stmt, tree *op_p) | |
1474 | { | |
ac182688 | 1475 | tree base = *op_p, step = NULL; |
8b11a64c ZD |
1476 | struct iv *civ; |
1477 | struct ifs_ivopts_data ifs_ivopts_data; | |
1478 | ||
e3cc7254 ZD |
1479 | /* Do not play with volatile memory references. A bit too conservative, |
1480 | perhaps, but safe. */ | |
1481 | if (stmt_ann (stmt)->has_volatile_ops) | |
1482 | goto fail; | |
1483 | ||
8b11a64c ZD |
1484 | /* Ignore bitfields for now. Not really something terribly complicated |
1485 | to handle. TODO. */ | |
dd79d394 ZD |
1486 | if (TREE_CODE (base) == BIT_FIELD_REF |
1487 | || (TREE_CODE (base) == COMPONENT_REF | |
1488 | && DECL_NONADDRESSABLE_P (TREE_OPERAND (base, 1)))) | |
8b11a64c ZD |
1489 | goto fail; |
1490 | ||
0a915e3d ZD |
1491 | if (STRICT_ALIGNMENT |
1492 | && may_be_unaligned_p (base)) | |
1493 | goto fail; | |
1494 | ||
ac182688 ZD |
1495 | base = unshare_expr (base); |
1496 | ||
1497 | if (TREE_CODE (base) == TARGET_MEM_REF) | |
1498 | { | |
1499 | tree type = build_pointer_type (TREE_TYPE (base)); | |
1500 | tree astep; | |
1501 | ||
1502 | if (TMR_BASE (base) | |
1503 | && TREE_CODE (TMR_BASE (base)) == SSA_NAME) | |
1504 | { | |
1505 | civ = get_iv (data, TMR_BASE (base)); | |
1506 | if (!civ) | |
1507 | goto fail; | |
1508 | ||
1509 | TMR_BASE (base) = civ->base; | |
1510 | step = civ->step; | |
1511 | } | |
1512 | if (TMR_INDEX (base) | |
1513 | && TREE_CODE (TMR_INDEX (base)) == SSA_NAME) | |
1514 | { | |
1515 | civ = get_iv (data, TMR_INDEX (base)); | |
1516 | if (!civ) | |
1517 | goto fail; | |
8b11a64c | 1518 | |
ac182688 ZD |
1519 | TMR_INDEX (base) = civ->base; |
1520 | astep = civ->step; | |
be35cf60 | 1521 | |
ac182688 ZD |
1522 | if (astep) |
1523 | { | |
1524 | if (TMR_STEP (base)) | |
1525 | astep = fold_build2 (MULT_EXPR, type, TMR_STEP (base), astep); | |
1526 | ||
1527 | if (step) | |
1528 | step = fold_build2 (PLUS_EXPR, type, step, astep); | |
1529 | else | |
1530 | step = astep; | |
1531 | } | |
1532 | } | |
1533 | ||
1534 | if (zero_p (step)) | |
1535 | goto fail; | |
1536 | base = tree_mem_ref_addr (type, base); | |
1537 | } | |
1538 | else | |
1539 | { | |
1540 | ifs_ivopts_data.ivopts_data = data; | |
1541 | ifs_ivopts_data.stmt = stmt; | |
1542 | ifs_ivopts_data.step_p = &step; | |
1543 | if (!for_each_index (&base, idx_find_step, &ifs_ivopts_data) | |
1544 | || zero_p (step)) | |
1545 | goto fail; | |
1546 | ||
1547 | gcc_assert (TREE_CODE (base) != ALIGN_INDIRECT_REF); | |
1548 | gcc_assert (TREE_CODE (base) != MISALIGNED_INDIRECT_REF); | |
1549 | ||
1550 | base = build_fold_addr_expr (base); | |
ea643120 RG |
1551 | |
1552 | /* Substituting bases of IVs into the base expression might | |
1553 | have caused folding opportunities. */ | |
1554 | if (TREE_CODE (base) == ADDR_EXPR) | |
1555 | { | |
1556 | tree *ref = &TREE_OPERAND (base, 0); | |
1557 | while (handled_component_p (*ref)) | |
1558 | ref = &TREE_OPERAND (*ref, 0); | |
1559 | if (TREE_CODE (*ref) == INDIRECT_REF) | |
1560 | *ref = fold_indirect_ref (*ref); | |
1561 | } | |
ac182688 | 1562 | } |
8b11a64c ZD |
1563 | |
1564 | civ = alloc_iv (base, step); | |
1565 | record_use (data, op_p, civ, stmt, USE_ADDRESS); | |
1566 | return; | |
1567 | ||
1568 | fail: | |
1569 | for_each_index (op_p, idx_record_use, data); | |
1570 | } | |
1571 | ||
1572 | /* Finds and records invariants used in STMT. */ | |
1573 | ||
1574 | static void | |
1575 | find_invariants_stmt (struct ivopts_data *data, tree stmt) | |
1576 | { | |
f47c96aa AM |
1577 | ssa_op_iter iter; |
1578 | use_operand_p use_p; | |
8b11a64c ZD |
1579 | tree op; |
1580 | ||
f47c96aa | 1581 | FOR_EACH_PHI_OR_STMT_USE (use_p, stmt, iter, SSA_OP_USE) |
8b11a64c | 1582 | { |
f47c96aa | 1583 | op = USE_FROM_PTR (use_p); |
8b11a64c ZD |
1584 | record_invariant (data, op, false); |
1585 | } | |
1586 | } | |
1587 | ||
1588 | /* Finds interesting uses of induction variables in the statement STMT. */ | |
1589 | ||
1590 | static void | |
1591 | find_interesting_uses_stmt (struct ivopts_data *data, tree stmt) | |
1592 | { | |
1593 | struct iv *iv; | |
1594 | tree op, lhs, rhs; | |
f47c96aa AM |
1595 | ssa_op_iter iter; |
1596 | use_operand_p use_p; | |
8b11a64c ZD |
1597 | |
1598 | find_invariants_stmt (data, stmt); | |
1599 | ||
1600 | if (TREE_CODE (stmt) == COND_EXPR) | |
1601 | { | |
1602 | find_interesting_uses_cond (data, stmt, &COND_EXPR_COND (stmt)); | |
1603 | return; | |
1604 | } | |
1605 | ||
1606 | if (TREE_CODE (stmt) == MODIFY_EXPR) | |
1607 | { | |
1608 | lhs = TREE_OPERAND (stmt, 0); | |
1609 | rhs = TREE_OPERAND (stmt, 1); | |
1610 | ||
1611 | if (TREE_CODE (lhs) == SSA_NAME) | |
1612 | { | |
1613 | /* If the statement defines an induction variable, the uses are not | |
1614 | interesting by themselves. */ | |
1615 | ||
1616 | iv = get_iv (data, lhs); | |
1617 | ||
1618 | if (iv && !zero_p (iv->step)) | |
1619 | return; | |
1620 | } | |
1621 | ||
1622 | switch (TREE_CODE_CLASS (TREE_CODE (rhs))) | |
1623 | { | |
6615c446 | 1624 | case tcc_comparison: |
8b11a64c ZD |
1625 | find_interesting_uses_cond (data, stmt, &TREE_OPERAND (stmt, 1)); |
1626 | return; | |
1627 | ||
6615c446 | 1628 | case tcc_reference: |
8b11a64c | 1629 | find_interesting_uses_address (data, stmt, &TREE_OPERAND (stmt, 1)); |
6615c446 | 1630 | if (REFERENCE_CLASS_P (lhs)) |
8b11a64c ZD |
1631 | find_interesting_uses_address (data, stmt, &TREE_OPERAND (stmt, 0)); |
1632 | return; | |
1633 | ||
1634 | default: ; | |
1635 | } | |
1636 | ||
6615c446 | 1637 | if (REFERENCE_CLASS_P (lhs) |
2f4675b4 | 1638 | && is_gimple_val (rhs)) |
8b11a64c ZD |
1639 | { |
1640 | find_interesting_uses_address (data, stmt, &TREE_OPERAND (stmt, 0)); | |
1641 | find_interesting_uses_op (data, rhs); | |
1642 | return; | |
1643 | } | |
2f4675b4 ZD |
1644 | |
1645 | /* TODO -- we should also handle address uses of type | |
1646 | ||
1647 | memory = call (whatever); | |
1648 | ||
1649 | and | |
1650 | ||
1651 | call (memory). */ | |
8b11a64c ZD |
1652 | } |
1653 | ||
1654 | if (TREE_CODE (stmt) == PHI_NODE | |
1655 | && bb_for_stmt (stmt) == data->current_loop->header) | |
1656 | { | |
1657 | lhs = PHI_RESULT (stmt); | |
1658 | iv = get_iv (data, lhs); | |
1659 | ||
1660 | if (iv && !zero_p (iv->step)) | |
1661 | return; | |
1662 | } | |
1663 | ||
f47c96aa | 1664 | FOR_EACH_PHI_OR_STMT_USE (use_p, stmt, iter, SSA_OP_USE) |
8b11a64c | 1665 | { |
f47c96aa | 1666 | op = USE_FROM_PTR (use_p); |
8b11a64c ZD |
1667 | |
1668 | if (TREE_CODE (op) != SSA_NAME) | |
1669 | continue; | |
1670 | ||
1671 | iv = get_iv (data, op); | |
1672 | if (!iv) | |
1673 | continue; | |
1674 | ||
1675 | find_interesting_uses_op (data, op); | |
1676 | } | |
1677 | } | |
1678 | ||
1679 | /* Finds interesting uses of induction variables outside of loops | |
1680 | on loop exit edge EXIT. */ | |
1681 | ||
1682 | static void | |
1683 | find_interesting_uses_outside (struct ivopts_data *data, edge exit) | |
1684 | { | |
1685 | tree phi, def; | |
1686 | ||
bb29d951 | 1687 | for (phi = phi_nodes (exit->dest); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
1688 | { |
1689 | def = PHI_ARG_DEF_FROM_EDGE (phi, exit); | |
50cc9802 | 1690 | find_interesting_uses_op (data, def); |
8b11a64c ZD |
1691 | } |
1692 | } | |
1693 | ||
1694 | /* Finds uses of the induction variables that are interesting. */ | |
1695 | ||
1696 | static void | |
1697 | find_interesting_uses (struct ivopts_data *data) | |
1698 | { | |
1699 | basic_block bb; | |
1700 | block_stmt_iterator bsi; | |
1701 | tree phi; | |
1702 | basic_block *body = get_loop_body (data->current_loop); | |
1703 | unsigned i; | |
1704 | struct version_info *info; | |
1705 | edge e; | |
1706 | ||
1707 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1708 | fprintf (dump_file, "Uses:\n\n"); | |
1709 | ||
1710 | for (i = 0; i < data->current_loop->num_nodes; i++) | |
1711 | { | |
628f6a4e | 1712 | edge_iterator ei; |
8b11a64c ZD |
1713 | bb = body[i]; |
1714 | ||
628f6a4e | 1715 | FOR_EACH_EDGE (e, ei, bb->succs) |
8b11a64c ZD |
1716 | if (e->dest != EXIT_BLOCK_PTR |
1717 | && !flow_bb_inside_loop_p (data->current_loop, e->dest)) | |
1718 | find_interesting_uses_outside (data, e); | |
1719 | ||
bb29d951 | 1720 | for (phi = phi_nodes (bb); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
1721 | find_interesting_uses_stmt (data, phi); |
1722 | for (bsi = bsi_start (bb); !bsi_end_p (bsi); bsi_next (&bsi)) | |
1723 | find_interesting_uses_stmt (data, bsi_stmt (bsi)); | |
1724 | } | |
1725 | ||
1726 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1727 | { | |
87c476a2 ZD |
1728 | bitmap_iterator bi; |
1729 | ||
8b11a64c ZD |
1730 | fprintf (dump_file, "\n"); |
1731 | ||
87c476a2 | 1732 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
8b11a64c ZD |
1733 | { |
1734 | info = ver_info (data, i); | |
1735 | if (info->inv_id) | |
1736 | { | |
1737 | fprintf (dump_file, " "); | |
1738 | print_generic_expr (dump_file, info->name, TDF_SLIM); | |
1739 | fprintf (dump_file, " is invariant (%d)%s\n", | |
1740 | info->inv_id, info->has_nonlin_use ? "" : ", eliminable"); | |
1741 | } | |
87c476a2 | 1742 | } |
8b11a64c ZD |
1743 | |
1744 | fprintf (dump_file, "\n"); | |
1745 | } | |
1746 | ||
1747 | free (body); | |
1748 | } | |
1749 | ||
f5e2738c | 1750 | /* Strips constant offsets from EXPR and stores them to OFFSET. If INSIDE_ADDR |
9be872b7 ZD |
1751 | is true, assume we are inside an address. If TOP_COMPREF is true, assume |
1752 | we are at the top-level of the processed address. */ | |
f5e2738c ZD |
1753 | |
1754 | static tree | |
9be872b7 ZD |
1755 | strip_offset_1 (tree expr, bool inside_addr, bool top_compref, |
1756 | unsigned HOST_WIDE_INT *offset) | |
f5e2738c | 1757 | { |
9be872b7 | 1758 | tree op0 = NULL_TREE, op1 = NULL_TREE, tmp, step; |
f5e2738c ZD |
1759 | enum tree_code code; |
1760 | tree type, orig_type = TREE_TYPE (expr); | |
1761 | unsigned HOST_WIDE_INT off0, off1, st; | |
1762 | tree orig_expr = expr; | |
1763 | ||
1764 | STRIP_NOPS (expr); | |
9be872b7 | 1765 | |
f5e2738c ZD |
1766 | type = TREE_TYPE (expr); |
1767 | code = TREE_CODE (expr); | |
1768 | *offset = 0; | |
1769 | ||
1770 | switch (code) | |
1771 | { | |
1772 | case INTEGER_CST: | |
1773 | if (!cst_and_fits_in_hwi (expr) | |
1774 | || zero_p (expr)) | |
1775 | return orig_expr; | |
1776 | ||
1777 | *offset = int_cst_value (expr); | |
ff5e9a94 | 1778 | return build_int_cst (orig_type, 0); |
f5e2738c ZD |
1779 | |
1780 | case PLUS_EXPR: | |
1781 | case MINUS_EXPR: | |
1782 | op0 = TREE_OPERAND (expr, 0); | |
1783 | op1 = TREE_OPERAND (expr, 1); | |
1784 | ||
9be872b7 ZD |
1785 | op0 = strip_offset_1 (op0, false, false, &off0); |
1786 | op1 = strip_offset_1 (op1, false, false, &off1); | |
f5e2738c ZD |
1787 | |
1788 | *offset = (code == PLUS_EXPR ? off0 + off1 : off0 - off1); | |
1789 | if (op0 == TREE_OPERAND (expr, 0) | |
1790 | && op1 == TREE_OPERAND (expr, 1)) | |
1791 | return orig_expr; | |
1792 | ||
1793 | if (zero_p (op1)) | |
1794 | expr = op0; | |
1795 | else if (zero_p (op0)) | |
1796 | { | |
1797 | if (code == PLUS_EXPR) | |
1798 | expr = op1; | |
1799 | else | |
9be872b7 | 1800 | expr = fold_build1 (NEGATE_EXPR, type, op1); |
f5e2738c ZD |
1801 | } |
1802 | else | |
9be872b7 | 1803 | expr = fold_build2 (code, type, op0, op1); |
f5e2738c ZD |
1804 | |
1805 | return fold_convert (orig_type, expr); | |
1806 | ||
1807 | case ARRAY_REF: | |
1808 | if (!inside_addr) | |
1809 | return orig_expr; | |
1810 | ||
1811 | step = array_ref_element_size (expr); | |
1812 | if (!cst_and_fits_in_hwi (step)) | |
1813 | break; | |
1814 | ||
1815 | st = int_cst_value (step); | |
1816 | op1 = TREE_OPERAND (expr, 1); | |
9be872b7 | 1817 | op1 = strip_offset_1 (op1, false, false, &off1); |
f5e2738c | 1818 | *offset = off1 * st; |
9be872b7 ZD |
1819 | |
1820 | if (top_compref | |
1821 | && zero_p (op1)) | |
1822 | { | |
1823 | /* Strip the component reference completely. */ | |
1824 | op0 = TREE_OPERAND (expr, 0); | |
1825 | op0 = strip_offset_1 (op0, inside_addr, top_compref, &off0); | |
1826 | *offset += off0; | |
1827 | return op0; | |
1828 | } | |
f5e2738c ZD |
1829 | break; |
1830 | ||
1831 | case COMPONENT_REF: | |
1832 | if (!inside_addr) | |
1833 | return orig_expr; | |
9be872b7 ZD |
1834 | |
1835 | tmp = component_ref_field_offset (expr); | |
1836 | if (top_compref | |
1837 | && cst_and_fits_in_hwi (tmp)) | |
1838 | { | |
1839 | /* Strip the component reference completely. */ | |
1840 | op0 = TREE_OPERAND (expr, 0); | |
1841 | op0 = strip_offset_1 (op0, inside_addr, top_compref, &off0); | |
1842 | *offset = off0 + int_cst_value (tmp); | |
1843 | return op0; | |
1844 | } | |
f5e2738c ZD |
1845 | break; |
1846 | ||
1847 | case ADDR_EXPR: | |
9be872b7 ZD |
1848 | op0 = TREE_OPERAND (expr, 0); |
1849 | op0 = strip_offset_1 (op0, true, true, &off0); | |
1850 | *offset += off0; | |
1851 | ||
1852 | if (op0 == TREE_OPERAND (expr, 0)) | |
1853 | return orig_expr; | |
1854 | ||
d5dc1717 | 1855 | expr = build_fold_addr_expr (op0); |
9be872b7 ZD |
1856 | return fold_convert (orig_type, expr); |
1857 | ||
1858 | case INDIRECT_REF: | |
1859 | inside_addr = false; | |
f5e2738c ZD |
1860 | break; |
1861 | ||
1862 | default: | |
1863 | return orig_expr; | |
1864 | } | |
1865 | ||
1866 | /* Default handling of expressions for that we want to recurse into | |
1867 | the first operand. */ | |
1868 | op0 = TREE_OPERAND (expr, 0); | |
9be872b7 | 1869 | op0 = strip_offset_1 (op0, inside_addr, false, &off0); |
f5e2738c ZD |
1870 | *offset += off0; |
1871 | ||
1872 | if (op0 == TREE_OPERAND (expr, 0) | |
1873 | && (!op1 || op1 == TREE_OPERAND (expr, 1))) | |
1874 | return orig_expr; | |
1875 | ||
1876 | expr = copy_node (expr); | |
1877 | TREE_OPERAND (expr, 0) = op0; | |
1878 | if (op1) | |
1879 | TREE_OPERAND (expr, 1) = op1; | |
1880 | ||
9be872b7 | 1881 | /* Inside address, we might strip the top level component references, |
0fa2e4df | 1882 | thus changing type of the expression. Handling of ADDR_EXPR |
9be872b7 ZD |
1883 | will fix that. */ |
1884 | expr = fold_convert (orig_type, expr); | |
1885 | ||
1886 | return expr; | |
1887 | } | |
1888 | ||
1889 | /* Strips constant offsets from EXPR and stores them to OFFSET. */ | |
1890 | ||
1891 | static tree | |
1892 | strip_offset (tree expr, unsigned HOST_WIDE_INT *offset) | |
1893 | { | |
1894 | return strip_offset_1 (expr, false, false, offset); | |
f5e2738c ZD |
1895 | } |
1896 | ||
d482f417 ZD |
1897 | /* Returns variant of TYPE that can be used as base for different uses. |
1898 | For integer types, we return unsigned variant of the type, which | |
1899 | avoids problems with overflows. For pointer types, we return void *. */ | |
1900 | ||
1901 | static tree | |
1902 | generic_type_for (tree type) | |
1903 | { | |
1904 | if (POINTER_TYPE_P (type)) | |
1905 | return ptr_type_node; | |
1906 | ||
1907 | if (TYPE_UNSIGNED (type)) | |
1908 | return type; | |
1909 | ||
1910 | return unsigned_type_for (type); | |
1911 | } | |
1912 | ||
9be872b7 ZD |
1913 | /* Records invariants in *EXPR_P. Callback for walk_tree. DATA contains |
1914 | the bitmap to that we should store it. */ | |
1915 | ||
1916 | static struct ivopts_data *fd_ivopts_data; | |
1917 | static tree | |
1918 | find_depends (tree *expr_p, int *ws ATTRIBUTE_UNUSED, void *data) | |
1919 | { | |
1920 | bitmap *depends_on = data; | |
1921 | struct version_info *info; | |
1922 | ||
1923 | if (TREE_CODE (*expr_p) != SSA_NAME) | |
1924 | return NULL_TREE; | |
1925 | info = name_info (fd_ivopts_data, *expr_p); | |
1926 | ||
1927 | if (!info->inv_id || info->has_nonlin_use) | |
1928 | return NULL_TREE; | |
1929 | ||
1930 | if (!*depends_on) | |
1931 | *depends_on = BITMAP_ALLOC (NULL); | |
1932 | bitmap_set_bit (*depends_on, info->inv_id); | |
1933 | ||
1934 | return NULL_TREE; | |
1935 | } | |
1936 | ||
8b11a64c ZD |
1937 | /* Adds a candidate BASE + STEP * i. Important field is set to IMPORTANT and |
1938 | position to POS. If USE is not NULL, the candidate is set as related to | |
1939 | it. If both BASE and STEP are NULL, we add a pseudocandidate for the | |
1940 | replacement of the final value of the iv by a direct computation. */ | |
1941 | ||
1942 | static struct iv_cand * | |
1943 | add_candidate_1 (struct ivopts_data *data, | |
1944 | tree base, tree step, bool important, enum iv_position pos, | |
1945 | struct iv_use *use, tree incremented_at) | |
1946 | { | |
1947 | unsigned i; | |
1948 | struct iv_cand *cand = NULL; | |
d482f417 | 1949 | tree type, orig_type; |
8b11a64c ZD |
1950 | |
1951 | if (base) | |
1952 | { | |
d482f417 ZD |
1953 | orig_type = TREE_TYPE (base); |
1954 | type = generic_type_for (orig_type); | |
1955 | if (type != orig_type) | |
8b11a64c | 1956 | { |
8b11a64c ZD |
1957 | base = fold_convert (type, base); |
1958 | if (step) | |
1959 | step = fold_convert (type, step); | |
1960 | } | |
1961 | } | |
1962 | ||
1963 | for (i = 0; i < n_iv_cands (data); i++) | |
1964 | { | |
1965 | cand = iv_cand (data, i); | |
1966 | ||
1967 | if (cand->pos != pos) | |
1968 | continue; | |
1969 | ||
1970 | if (cand->incremented_at != incremented_at) | |
1971 | continue; | |
1972 | ||
1973 | if (!cand->iv) | |
1974 | { | |
1975 | if (!base && !step) | |
1976 | break; | |
1977 | ||
1978 | continue; | |
1979 | } | |
1980 | ||
1981 | if (!base && !step) | |
1982 | continue; | |
1983 | ||
1984 | if (!operand_equal_p (base, cand->iv->base, 0)) | |
1985 | continue; | |
1986 | ||
1987 | if (zero_p (cand->iv->step)) | |
1988 | { | |
1989 | if (zero_p (step)) | |
1990 | break; | |
1991 | } | |
1992 | else | |
1993 | { | |
1994 | if (step && operand_equal_p (step, cand->iv->step, 0)) | |
1995 | break; | |
1996 | } | |
1997 | } | |
1998 | ||
1999 | if (i == n_iv_cands (data)) | |
2000 | { | |
5ed6ace5 | 2001 | cand = XCNEW (struct iv_cand); |
8b11a64c ZD |
2002 | cand->id = i; |
2003 | ||
2004 | if (!base && !step) | |
2005 | cand->iv = NULL; | |
2006 | else | |
2007 | cand->iv = alloc_iv (base, step); | |
2008 | ||
2009 | cand->pos = pos; | |
2010 | if (pos != IP_ORIGINAL && cand->iv) | |
2011 | { | |
2012 | cand->var_before = create_tmp_var_raw (TREE_TYPE (base), "ivtmp"); | |
2013 | cand->var_after = cand->var_before; | |
2014 | } | |
2015 | cand->important = important; | |
2016 | cand->incremented_at = incremented_at; | |
69ebd99d | 2017 | VEC_safe_push (iv_cand_p, heap, data->iv_candidates, cand); |
8b11a64c | 2018 | |
9be872b7 ZD |
2019 | if (step |
2020 | && TREE_CODE (step) != INTEGER_CST) | |
2021 | { | |
2022 | fd_ivopts_data = data; | |
2023 | walk_tree (&step, find_depends, &cand->depends_on, NULL); | |
2024 | } | |
2025 | ||
8b11a64c ZD |
2026 | if (dump_file && (dump_flags & TDF_DETAILS)) |
2027 | dump_cand (dump_file, cand); | |
2028 | } | |
2029 | ||
2030 | if (important && !cand->important) | |
2031 | { | |
2032 | cand->important = true; | |
2033 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2034 | fprintf (dump_file, "Candidate %d is important\n", cand->id); | |
2035 | } | |
2036 | ||
2037 | if (use) | |
2038 | { | |
2039 | bitmap_set_bit (use->related_cands, i); | |
2040 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
2041 | fprintf (dump_file, "Candidate %d is related to use %d\n", | |
2042 | cand->id, use->id); | |
2043 | } | |
2044 | ||
2045 | return cand; | |
2046 | } | |
2047 | ||
4366cf6d ZD |
2048 | /* Returns true if incrementing the induction variable at the end of the LOOP |
2049 | is allowed. | |
2050 | ||
2051 | The purpose is to avoid splitting latch edge with a biv increment, thus | |
2052 | creating a jump, possibly confusing other optimization passes and leaving | |
2053 | less freedom to scheduler. So we allow IP_END_POS only if IP_NORMAL_POS | |
2054 | is not available (so we do not have a better alternative), or if the latch | |
2055 | edge is already nonempty. */ | |
2056 | ||
2057 | static bool | |
2058 | allow_ip_end_pos_p (struct loop *loop) | |
2059 | { | |
2060 | if (!ip_normal_pos (loop)) | |
2061 | return true; | |
2062 | ||
2063 | if (!empty_block_p (ip_end_pos (loop))) | |
2064 | return true; | |
2065 | ||
2066 | return false; | |
2067 | } | |
2068 | ||
8b11a64c ZD |
2069 | /* Adds a candidate BASE + STEP * i. Important field is set to IMPORTANT and |
2070 | position to POS. If USE is not NULL, the candidate is set as related to | |
2071 | it. The candidate computation is scheduled on all available positions. */ | |
2072 | ||
2073 | static void | |
2074 | add_candidate (struct ivopts_data *data, | |
2075 | tree base, tree step, bool important, struct iv_use *use) | |
2076 | { | |
2077 | if (ip_normal_pos (data->current_loop)) | |
2078 | add_candidate_1 (data, base, step, important, IP_NORMAL, use, NULL_TREE); | |
4366cf6d ZD |
2079 | if (ip_end_pos (data->current_loop) |
2080 | && allow_ip_end_pos_p (data->current_loop)) | |
8b11a64c ZD |
2081 | add_candidate_1 (data, base, step, important, IP_END, use, NULL_TREE); |
2082 | } | |
2083 | ||
39b4020c RS |
2084 | /* Add a standard "0 + 1 * iteration" iv candidate for a |
2085 | type with SIZE bits. */ | |
2086 | ||
2087 | static void | |
2088 | add_standard_iv_candidates_for_size (struct ivopts_data *data, | |
2089 | unsigned int size) | |
2090 | { | |
2091 | tree type = lang_hooks.types.type_for_size (size, true); | |
2092 | add_candidate (data, build_int_cst (type, 0), build_int_cst (type, 1), | |
2093 | true, NULL); | |
2094 | } | |
2095 | ||
8b11a64c ZD |
2096 | /* Adds standard iv candidates. */ |
2097 | ||
2098 | static void | |
2099 | add_standard_iv_candidates (struct ivopts_data *data) | |
2100 | { | |
39b4020c | 2101 | add_standard_iv_candidates_for_size (data, INT_TYPE_SIZE); |
8b11a64c | 2102 | |
39b4020c RS |
2103 | /* The same for a double-integer type if it is still fast enough. */ |
2104 | if (BITS_PER_WORD >= INT_TYPE_SIZE * 2) | |
2105 | add_standard_iv_candidates_for_size (data, INT_TYPE_SIZE * 2); | |
8b11a64c ZD |
2106 | } |
2107 | ||
2108 | ||
2109 | /* Adds candidates bases on the old induction variable IV. */ | |
2110 | ||
2111 | static void | |
2112 | add_old_iv_candidates (struct ivopts_data *data, struct iv *iv) | |
2113 | { | |
2114 | tree phi, def; | |
2115 | struct iv_cand *cand; | |
2116 | ||
2117 | add_candidate (data, iv->base, iv->step, true, NULL); | |
2118 | ||
2119 | /* The same, but with initial value zero. */ | |
2120 | add_candidate (data, | |
5212068f | 2121 | build_int_cst (TREE_TYPE (iv->base), 0), |
8b11a64c ZD |
2122 | iv->step, true, NULL); |
2123 | ||
2124 | phi = SSA_NAME_DEF_STMT (iv->ssa_name); | |
2125 | if (TREE_CODE (phi) == PHI_NODE) | |
2126 | { | |
2127 | /* Additionally record the possibility of leaving the original iv | |
2128 | untouched. */ | |
2129 | def = PHI_ARG_DEF_FROM_EDGE (phi, loop_latch_edge (data->current_loop)); | |
2130 | cand = add_candidate_1 (data, | |
2131 | iv->base, iv->step, true, IP_ORIGINAL, NULL, | |
2132 | SSA_NAME_DEF_STMT (def)); | |
2133 | cand->var_before = iv->ssa_name; | |
2134 | cand->var_after = def; | |
2135 | } | |
2136 | } | |
2137 | ||
2138 | /* Adds candidates based on the old induction variables. */ | |
2139 | ||
2140 | static void | |
2141 | add_old_ivs_candidates (struct ivopts_data *data) | |
2142 | { | |
2143 | unsigned i; | |
2144 | struct iv *iv; | |
87c476a2 | 2145 | bitmap_iterator bi; |
8b11a64c | 2146 | |
87c476a2 | 2147 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
8b11a64c ZD |
2148 | { |
2149 | iv = ver_info (data, i)->iv; | |
2150 | if (iv && iv->biv_p && !zero_p (iv->step)) | |
2151 | add_old_iv_candidates (data, iv); | |
87c476a2 | 2152 | } |
8b11a64c ZD |
2153 | } |
2154 | ||
2155 | /* Adds candidates based on the value of the induction variable IV and USE. */ | |
2156 | ||
2157 | static void | |
2158 | add_iv_value_candidates (struct ivopts_data *data, | |
2159 | struct iv *iv, struct iv_use *use) | |
2160 | { | |
f5e2738c | 2161 | unsigned HOST_WIDE_INT offset; |
9be872b7 | 2162 | tree base; |
8b11a64c | 2163 | |
9be872b7 | 2164 | add_candidate (data, iv->base, iv->step, false, use); |
be35cf60 | 2165 | |
9be872b7 ZD |
2166 | /* The same, but with initial value zero. Make such variable important, |
2167 | since it is generic enough so that possibly many uses may be based | |
2168 | on it. */ | |
2169 | add_candidate (data, build_int_cst (TREE_TYPE (iv->base), 0), | |
2170 | iv->step, true, use); | |
8b11a64c ZD |
2171 | |
2172 | /* Third, try removing the constant offset. */ | |
9be872b7 | 2173 | base = strip_offset (iv->base, &offset); |
f5e2738c ZD |
2174 | if (offset) |
2175 | add_candidate (data, base, iv->step, false, use); | |
8b11a64c ZD |
2176 | } |
2177 | ||
8b11a64c ZD |
2178 | /* Adds candidates based on the uses. */ |
2179 | ||
2180 | static void | |
2181 | add_derived_ivs_candidates (struct ivopts_data *data) | |
2182 | { | |
2183 | unsigned i; | |
2184 | ||
2185 | for (i = 0; i < n_iv_uses (data); i++) | |
2186 | { | |
2187 | struct iv_use *use = iv_use (data, i); | |
2188 | ||
2189 | if (!use) | |
2190 | continue; | |
2191 | ||
2192 | switch (use->type) | |
2193 | { | |
2194 | case USE_NONLINEAR_EXPR: | |
2195 | case USE_COMPARE: | |
9be872b7 | 2196 | case USE_ADDRESS: |
8b11a64c ZD |
2197 | /* Just add the ivs based on the value of the iv used here. */ |
2198 | add_iv_value_candidates (data, use->iv, use); | |
2199 | break; | |
2200 | ||
8b11a64c | 2201 | default: |
1e128c5f | 2202 | gcc_unreachable (); |
8b11a64c ZD |
2203 | } |
2204 | } | |
2205 | } | |
2206 | ||
b1b02be2 ZD |
2207 | /* Record important candidates and add them to related_cands bitmaps |
2208 | if needed. */ | |
2209 | ||
2210 | static void | |
2211 | record_important_candidates (struct ivopts_data *data) | |
2212 | { | |
2213 | unsigned i; | |
2214 | struct iv_use *use; | |
2215 | ||
2216 | for (i = 0; i < n_iv_cands (data); i++) | |
2217 | { | |
2218 | struct iv_cand *cand = iv_cand (data, i); | |
2219 | ||
2220 | if (cand->important) | |
2221 | bitmap_set_bit (data->important_candidates, i); | |
2222 | } | |
2223 | ||
2224 | data->consider_all_candidates = (n_iv_cands (data) | |
2225 | <= CONSIDER_ALL_CANDIDATES_BOUND); | |
2226 | ||
2227 | if (data->consider_all_candidates) | |
2228 | { | |
2229 | /* We will not need "related_cands" bitmaps in this case, | |
2230 | so release them to decrease peak memory consumption. */ | |
2231 | for (i = 0; i < n_iv_uses (data); i++) | |
2232 | { | |
2233 | use = iv_use (data, i); | |
8bdbfff5 | 2234 | BITMAP_FREE (use->related_cands); |
b1b02be2 ZD |
2235 | } |
2236 | } | |
2237 | else | |
2238 | { | |
2239 | /* Add important candidates to the related_cands bitmaps. */ | |
2240 | for (i = 0; i < n_iv_uses (data); i++) | |
2241 | bitmap_ior_into (iv_use (data, i)->related_cands, | |
2242 | data->important_candidates); | |
2243 | } | |
2244 | } | |
2245 | ||
8b11a64c ZD |
2246 | /* Finds the candidates for the induction variables. */ |
2247 | ||
2248 | static void | |
2249 | find_iv_candidates (struct ivopts_data *data) | |
2250 | { | |
2251 | /* Add commonly used ivs. */ | |
2252 | add_standard_iv_candidates (data); | |
2253 | ||
2254 | /* Add old induction variables. */ | |
2255 | add_old_ivs_candidates (data); | |
2256 | ||
2257 | /* Add induction variables derived from uses. */ | |
2258 | add_derived_ivs_candidates (data); | |
b1b02be2 ZD |
2259 | |
2260 | /* Record the important candidates. */ | |
2261 | record_important_candidates (data); | |
8b11a64c ZD |
2262 | } |
2263 | ||
2264 | /* Allocates the data structure mapping the (use, candidate) pairs to costs. | |
2265 | If consider_all_candidates is true, we use a two-dimensional array, otherwise | |
2266 | we allocate a simple list to every use. */ | |
2267 | ||
2268 | static void | |
2269 | alloc_use_cost_map (struct ivopts_data *data) | |
2270 | { | |
b1b02be2 | 2271 | unsigned i, size, s, j; |
8b11a64c ZD |
2272 | |
2273 | for (i = 0; i < n_iv_uses (data); i++) | |
2274 | { | |
2275 | struct iv_use *use = iv_use (data, i); | |
87c476a2 | 2276 | bitmap_iterator bi; |
8b11a64c ZD |
2277 | |
2278 | if (data->consider_all_candidates) | |
b1b02be2 | 2279 | size = n_iv_cands (data); |
8b11a64c ZD |
2280 | else |
2281 | { | |
b1b02be2 | 2282 | s = 0; |
87c476a2 ZD |
2283 | EXECUTE_IF_SET_IN_BITMAP (use->related_cands, 0, j, bi) |
2284 | { | |
b1b02be2 | 2285 | s++; |
87c476a2 | 2286 | } |
b1b02be2 ZD |
2287 | |
2288 | /* Round up to the power of two, so that moduling by it is fast. */ | |
2289 | for (size = 1; size < s; size <<= 1) | |
2290 | continue; | |
8b11a64c ZD |
2291 | } |
2292 | ||
b1b02be2 | 2293 | use->n_map_members = size; |
5ed6ace5 | 2294 | use->cost_map = XCNEWVEC (struct cost_pair, size); |
8b11a64c ZD |
2295 | } |
2296 | } | |
2297 | ||
2298 | /* Sets cost of (USE, CANDIDATE) pair to COST and record that it depends | |
f5f12961 ZD |
2299 | on invariants DEPENDS_ON and that the value used in expressing it |
2300 | is VALUE.*/ | |
8b11a64c ZD |
2301 | |
2302 | static void | |
2303 | set_use_iv_cost (struct ivopts_data *data, | |
2304 | struct iv_use *use, struct iv_cand *cand, unsigned cost, | |
f5f12961 | 2305 | bitmap depends_on, tree value) |
8b11a64c | 2306 | { |
b1b02be2 ZD |
2307 | unsigned i, s; |
2308 | ||
2309 | if (cost == INFTY) | |
8b11a64c | 2310 | { |
8bdbfff5 | 2311 | BITMAP_FREE (depends_on); |
b1b02be2 | 2312 | return; |
8b11a64c ZD |
2313 | } |
2314 | ||
2315 | if (data->consider_all_candidates) | |
2316 | { | |
2317 | use->cost_map[cand->id].cand = cand; | |
2318 | use->cost_map[cand->id].cost = cost; | |
2319 | use->cost_map[cand->id].depends_on = depends_on; | |
f5f12961 | 2320 | use->cost_map[cand->id].value = value; |
8b11a64c ZD |
2321 | return; |
2322 | } | |
2323 | ||
b1b02be2 ZD |
2324 | /* n_map_members is a power of two, so this computes modulo. */ |
2325 | s = cand->id & (use->n_map_members - 1); | |
2326 | for (i = s; i < use->n_map_members; i++) | |
2327 | if (!use->cost_map[i].cand) | |
2328 | goto found; | |
2329 | for (i = 0; i < s; i++) | |
2330 | if (!use->cost_map[i].cand) | |
2331 | goto found; | |
2332 | ||
2333 | gcc_unreachable (); | |
8b11a64c | 2334 | |
b1b02be2 ZD |
2335 | found: |
2336 | use->cost_map[i].cand = cand; | |
2337 | use->cost_map[i].cost = cost; | |
2338 | use->cost_map[i].depends_on = depends_on; | |
f5f12961 | 2339 | use->cost_map[i].value = value; |
8b11a64c ZD |
2340 | } |
2341 | ||
b1b02be2 | 2342 | /* Gets cost of (USE, CANDIDATE) pair. */ |
8b11a64c | 2343 | |
b1b02be2 ZD |
2344 | static struct cost_pair * |
2345 | get_use_iv_cost (struct ivopts_data *data, struct iv_use *use, | |
2346 | struct iv_cand *cand) | |
8b11a64c | 2347 | { |
b1b02be2 ZD |
2348 | unsigned i, s; |
2349 | struct cost_pair *ret; | |
8b11a64c ZD |
2350 | |
2351 | if (!cand) | |
b1b02be2 | 2352 | return NULL; |
8b11a64c ZD |
2353 | |
2354 | if (data->consider_all_candidates) | |
8b11a64c | 2355 | { |
b1b02be2 ZD |
2356 | ret = use->cost_map + cand->id; |
2357 | if (!ret->cand) | |
2358 | return NULL; | |
8b11a64c | 2359 | |
b1b02be2 | 2360 | return ret; |
8b11a64c | 2361 | } |
b1b02be2 ZD |
2362 | |
2363 | /* n_map_members is a power of two, so this computes modulo. */ | |
2364 | s = cand->id & (use->n_map_members - 1); | |
2365 | for (i = s; i < use->n_map_members; i++) | |
2366 | if (use->cost_map[i].cand == cand) | |
2367 | return use->cost_map + i; | |
8b11a64c | 2368 | |
b1b02be2 ZD |
2369 | for (i = 0; i < s; i++) |
2370 | if (use->cost_map[i].cand == cand) | |
2371 | return use->cost_map + i; | |
2372 | ||
2373 | return NULL; | |
8b11a64c ZD |
2374 | } |
2375 | ||
2376 | /* Returns estimate on cost of computing SEQ. */ | |
2377 | ||
2378 | static unsigned | |
2379 | seq_cost (rtx seq) | |
2380 | { | |
2381 | unsigned cost = 0; | |
2382 | rtx set; | |
2383 | ||
2384 | for (; seq; seq = NEXT_INSN (seq)) | |
2385 | { | |
2386 | set = single_set (seq); | |
2387 | if (set) | |
2388 | cost += rtx_cost (set, SET); | |
2389 | else | |
2390 | cost++; | |
2391 | } | |
2392 | ||
2393 | return cost; | |
2394 | } | |
2395 | ||
8679c649 JH |
2396 | /* Produce DECL_RTL for object obj so it looks like it is stored in memory. */ |
2397 | static rtx | |
2398 | produce_memory_decl_rtl (tree obj, int *regno) | |
2399 | { | |
2400 | rtx x; | |
e16acfcd NS |
2401 | |
2402 | gcc_assert (obj); | |
8679c649 JH |
2403 | if (TREE_STATIC (obj) || DECL_EXTERNAL (obj)) |
2404 | { | |
2405 | const char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (obj)); | |
2406 | x = gen_rtx_SYMBOL_REF (Pmode, name); | |
2407 | } | |
2408 | else | |
2409 | x = gen_raw_REG (Pmode, (*regno)++); | |
2410 | ||
2411 | return gen_rtx_MEM (DECL_MODE (obj), x); | |
2412 | } | |
2413 | ||
8b11a64c ZD |
2414 | /* Prepares decl_rtl for variables referred in *EXPR_P. Callback for |
2415 | walk_tree. DATA contains the actual fake register number. */ | |
2416 | ||
2417 | static tree | |
2418 | prepare_decl_rtl (tree *expr_p, int *ws, void *data) | |
2419 | { | |
2420 | tree obj = NULL_TREE; | |
2421 | rtx x = NULL_RTX; | |
2422 | int *regno = data; | |
2423 | ||
2424 | switch (TREE_CODE (*expr_p)) | |
2425 | { | |
8679c649 JH |
2426 | case ADDR_EXPR: |
2427 | for (expr_p = &TREE_OPERAND (*expr_p, 0); | |
afe84921 RH |
2428 | handled_component_p (*expr_p); |
2429 | expr_p = &TREE_OPERAND (*expr_p, 0)) | |
2430 | continue; | |
8679c649 | 2431 | obj = *expr_p; |
aacd3885 | 2432 | if (DECL_P (obj) && !DECL_RTL_SET_P (obj)) |
8679c649 JH |
2433 | x = produce_memory_decl_rtl (obj, regno); |
2434 | break; | |
2435 | ||
8b11a64c ZD |
2436 | case SSA_NAME: |
2437 | *ws = 0; | |
2438 | obj = SSA_NAME_VAR (*expr_p); | |
2439 | if (!DECL_RTL_SET_P (obj)) | |
2440 | x = gen_raw_REG (DECL_MODE (obj), (*regno)++); | |
2441 | break; | |
2442 | ||
2443 | case VAR_DECL: | |
2444 | case PARM_DECL: | |
2445 | case RESULT_DECL: | |
2446 | *ws = 0; | |
2447 | obj = *expr_p; | |
2448 | ||
2449 | if (DECL_RTL_SET_P (obj)) | |
2450 | break; | |
2451 | ||
2452 | if (DECL_MODE (obj) == BLKmode) | |
8679c649 | 2453 | x = produce_memory_decl_rtl (obj, regno); |
8b11a64c ZD |
2454 | else |
2455 | x = gen_raw_REG (DECL_MODE (obj), (*regno)++); | |
2456 | ||
2457 | break; | |
2458 | ||
2459 | default: | |
2460 | break; | |
2461 | } | |
2462 | ||
2463 | if (x) | |
2464 | { | |
69ebd99d | 2465 | VEC_safe_push (tree, heap, decl_rtl_to_reset, obj); |
8b11a64c ZD |
2466 | SET_DECL_RTL (obj, x); |
2467 | } | |
2468 | ||
2469 | return NULL_TREE; | |
2470 | } | |
2471 | ||
2472 | /* Determines cost of the computation of EXPR. */ | |
2473 | ||
2474 | static unsigned | |
2475 | computation_cost (tree expr) | |
2476 | { | |
2477 | rtx seq, rslt; | |
2478 | tree type = TREE_TYPE (expr); | |
2479 | unsigned cost; | |
1d27fed4 DD |
2480 | /* Avoid using hard regs in ways which may be unsupported. */ |
2481 | int regno = LAST_VIRTUAL_REGISTER + 1; | |
8b11a64c ZD |
2482 | |
2483 | walk_tree (&expr, prepare_decl_rtl, ®no, NULL); | |
2484 | start_sequence (); | |
2485 | rslt = expand_expr (expr, NULL_RTX, TYPE_MODE (type), EXPAND_NORMAL); | |
2486 | seq = get_insns (); | |
2487 | end_sequence (); | |
2488 | ||
2489 | cost = seq_cost (seq); | |
2ca202e7 | 2490 | if (MEM_P (rslt)) |
8b11a64c ZD |
2491 | cost += address_cost (XEXP (rslt, 0), TYPE_MODE (type)); |
2492 | ||
2493 | return cost; | |
2494 | } | |
2495 | ||
2496 | /* Returns variable containing the value of candidate CAND at statement AT. */ | |
2497 | ||
2498 | static tree | |
2499 | var_at_stmt (struct loop *loop, struct iv_cand *cand, tree stmt) | |
2500 | { | |
2501 | if (stmt_after_increment (loop, cand, stmt)) | |
2502 | return cand->var_after; | |
2503 | else | |
2504 | return cand->var_before; | |
2505 | } | |
2506 | ||
9be872b7 ZD |
2507 | /* Return the most significant (sign) bit of T. Similar to tree_int_cst_msb, |
2508 | but the bit is determined from TYPE_PRECISION, not MODE_BITSIZE. */ | |
2509 | ||
d7bf3bcf | 2510 | int |
9be872b7 ZD |
2511 | tree_int_cst_sign_bit (tree t) |
2512 | { | |
2513 | unsigned bitno = TYPE_PRECISION (TREE_TYPE (t)) - 1; | |
2514 | unsigned HOST_WIDE_INT w; | |
2515 | ||
2516 | if (bitno < HOST_BITS_PER_WIDE_INT) | |
2517 | w = TREE_INT_CST_LOW (t); | |
2518 | else | |
2519 | { | |
2520 | w = TREE_INT_CST_HIGH (t); | |
2521 | bitno -= HOST_BITS_PER_WIDE_INT; | |
2522 | } | |
2523 | ||
2524 | return (w >> bitno) & 1; | |
2525 | } | |
2526 | ||
2527 | /* If we can prove that TOP = cst * BOT for some constant cst in TYPE, | |
2528 | return cst. Otherwise return NULL_TREE. */ | |
2529 | ||
2530 | static tree | |
2531 | constant_multiple_of (tree type, tree top, tree bot) | |
2532 | { | |
2533 | tree res, mby, p0, p1; | |
2534 | enum tree_code code; | |
2535 | bool negate; | |
2536 | ||
2537 | STRIP_NOPS (top); | |
2538 | STRIP_NOPS (bot); | |
2539 | ||
2540 | if (operand_equal_p (top, bot, 0)) | |
2541 | return build_int_cst (type, 1); | |
2542 | ||
2543 | code = TREE_CODE (top); | |
2544 | switch (code) | |
2545 | { | |
2546 | case MULT_EXPR: | |
2547 | mby = TREE_OPERAND (top, 1); | |
2548 | if (TREE_CODE (mby) != INTEGER_CST) | |
2549 | return NULL_TREE; | |
2550 | ||
2551 | res = constant_multiple_of (type, TREE_OPERAND (top, 0), bot); | |
2552 | if (!res) | |
2553 | return NULL_TREE; | |
2554 | ||
2555 | return fold_binary_to_constant (MULT_EXPR, type, res, | |
2556 | fold_convert (type, mby)); | |
2557 | ||
2558 | case PLUS_EXPR: | |
2559 | case MINUS_EXPR: | |
2560 | p0 = constant_multiple_of (type, TREE_OPERAND (top, 0), bot); | |
2561 | if (!p0) | |
2562 | return NULL_TREE; | |
2563 | p1 = constant_multiple_of (type, TREE_OPERAND (top, 1), bot); | |
2564 | if (!p1) | |
2565 | return NULL_TREE; | |
2566 | ||
2567 | return fold_binary_to_constant (code, type, p0, p1); | |
2568 | ||
2569 | case INTEGER_CST: | |
2570 | if (TREE_CODE (bot) != INTEGER_CST) | |
2571 | return NULL_TREE; | |
2572 | ||
2573 | bot = fold_convert (type, bot); | |
2574 | top = fold_convert (type, top); | |
2575 | ||
2576 | /* If BOT seems to be negative, try dividing by -BOT instead, and negate | |
2577 | the result afterwards. */ | |
2578 | if (tree_int_cst_sign_bit (bot)) | |
2579 | { | |
2580 | negate = true; | |
2581 | bot = fold_unary_to_constant (NEGATE_EXPR, type, bot); | |
2582 | } | |
2583 | else | |
2584 | negate = false; | |
2585 | ||
2586 | /* Ditto for TOP. */ | |
2587 | if (tree_int_cst_sign_bit (top)) | |
2588 | { | |
2589 | negate = !negate; | |
2590 | top = fold_unary_to_constant (NEGATE_EXPR, type, top); | |
2591 | } | |
2592 | ||
2593 | if (!zero_p (fold_binary_to_constant (TRUNC_MOD_EXPR, type, top, bot))) | |
2594 | return NULL_TREE; | |
2595 | ||
2596 | res = fold_binary_to_constant (EXACT_DIV_EXPR, type, top, bot); | |
2597 | if (negate) | |
2598 | res = fold_unary_to_constant (NEGATE_EXPR, type, res); | |
2599 | return res; | |
2600 | ||
2601 | default: | |
2602 | return NULL_TREE; | |
2603 | } | |
2604 | } | |
2605 | ||
9be872b7 ZD |
2606 | /* Sets COMB to CST. */ |
2607 | ||
2608 | static void | |
2609 | aff_combination_const (struct affine_tree_combination *comb, tree type, | |
2610 | unsigned HOST_WIDE_INT cst) | |
2611 | { | |
2612 | unsigned prec = TYPE_PRECISION (type); | |
2613 | ||
2614 | comb->type = type; | |
2615 | comb->mask = (((unsigned HOST_WIDE_INT) 2 << (prec - 1)) - 1); | |
2616 | ||
2617 | comb->n = 0; | |
2618 | comb->rest = NULL_TREE; | |
2619 | comb->offset = cst & comb->mask; | |
2620 | } | |
2621 | ||
2622 | /* Sets COMB to single element ELT. */ | |
2623 | ||
2624 | static void | |
2625 | aff_combination_elt (struct affine_tree_combination *comb, tree type, tree elt) | |
2626 | { | |
2627 | unsigned prec = TYPE_PRECISION (type); | |
2628 | ||
2629 | comb->type = type; | |
2630 | comb->mask = (((unsigned HOST_WIDE_INT) 2 << (prec - 1)) - 1); | |
2631 | ||
2632 | comb->n = 1; | |
2633 | comb->elts[0] = elt; | |
2634 | comb->coefs[0] = 1; | |
2635 | comb->rest = NULL_TREE; | |
2636 | comb->offset = 0; | |
2637 | } | |
2638 | ||
2639 | /* Scales COMB by SCALE. */ | |
2640 | ||
2641 | static void | |
2642 | aff_combination_scale (struct affine_tree_combination *comb, | |
2643 | unsigned HOST_WIDE_INT scale) | |
2644 | { | |
2645 | unsigned i, j; | |
2646 | ||
2647 | if (scale == 1) | |
2648 | return; | |
2649 | ||
2650 | if (scale == 0) | |
2651 | { | |
2652 | aff_combination_const (comb, comb->type, 0); | |
2653 | return; | |
2654 | } | |
2655 | ||
2656 | comb->offset = (scale * comb->offset) & comb->mask; | |
2657 | for (i = 0, j = 0; i < comb->n; i++) | |
2658 | { | |
2659 | comb->coefs[j] = (scale * comb->coefs[i]) & comb->mask; | |
2660 | comb->elts[j] = comb->elts[i]; | |
2661 | if (comb->coefs[j] != 0) | |
2662 | j++; | |
2663 | } | |
2664 | comb->n = j; | |
2665 | ||
2666 | if (comb->rest) | |
2667 | { | |
2668 | if (comb->n < MAX_AFF_ELTS) | |
2669 | { | |
2670 | comb->coefs[comb->n] = scale; | |
2671 | comb->elts[comb->n] = comb->rest; | |
2672 | comb->rest = NULL_TREE; | |
2673 | comb->n++; | |
2674 | } | |
2675 | else | |
2676 | comb->rest = fold_build2 (MULT_EXPR, comb->type, comb->rest, | |
2677 | build_int_cst_type (comb->type, scale)); | |
2678 | } | |
2679 | } | |
2680 | ||
2681 | /* Adds ELT * SCALE to COMB. */ | |
2682 | ||
2683 | static void | |
2684 | aff_combination_add_elt (struct affine_tree_combination *comb, tree elt, | |
2685 | unsigned HOST_WIDE_INT scale) | |
2686 | { | |
2687 | unsigned i; | |
2688 | ||
2689 | if (scale == 0) | |
2690 | return; | |
2691 | ||
2692 | for (i = 0; i < comb->n; i++) | |
2693 | if (operand_equal_p (comb->elts[i], elt, 0)) | |
2694 | { | |
2695 | comb->coefs[i] = (comb->coefs[i] + scale) & comb->mask; | |
2696 | if (comb->coefs[i]) | |
2697 | return; | |
2698 | ||
2699 | comb->n--; | |
2700 | comb->coefs[i] = comb->coefs[comb->n]; | |
2701 | comb->elts[i] = comb->elts[comb->n]; | |
98d59fe6 ZD |
2702 | |
2703 | if (comb->rest) | |
2704 | { | |
2705 | gcc_assert (comb->n == MAX_AFF_ELTS - 1); | |
2706 | comb->coefs[comb->n] = 1; | |
2707 | comb->elts[comb->n] = comb->rest; | |
2708 | comb->rest = NULL_TREE; | |
2709 | comb->n++; | |
2710 | } | |
9be872b7 ZD |
2711 | return; |
2712 | } | |
2713 | if (comb->n < MAX_AFF_ELTS) | |
2714 | { | |
2715 | comb->coefs[comb->n] = scale; | |
2716 | comb->elts[comb->n] = elt; | |
2717 | comb->n++; | |
2718 | return; | |
2719 | } | |
2720 | ||
2721 | if (scale == 1) | |
2722 | elt = fold_convert (comb->type, elt); | |
2723 | else | |
2724 | elt = fold_build2 (MULT_EXPR, comb->type, | |
2725 | fold_convert (comb->type, elt), | |
2726 | build_int_cst_type (comb->type, scale)); | |
2727 | ||
2728 | if (comb->rest) | |
2729 | comb->rest = fold_build2 (PLUS_EXPR, comb->type, comb->rest, elt); | |
2730 | else | |
2731 | comb->rest = elt; | |
2732 | } | |
2733 | ||
2734 | /* Adds COMB2 to COMB1. */ | |
2735 | ||
2736 | static void | |
2737 | aff_combination_add (struct affine_tree_combination *comb1, | |
2738 | struct affine_tree_combination *comb2) | |
2739 | { | |
2740 | unsigned i; | |
2741 | ||
2742 | comb1->offset = (comb1->offset + comb2->offset) & comb1->mask; | |
98d59fe6 | 2743 | for (i = 0; i < comb2->n; i++) |
9be872b7 ZD |
2744 | aff_combination_add_elt (comb1, comb2->elts[i], comb2->coefs[i]); |
2745 | if (comb2->rest) | |
2746 | aff_combination_add_elt (comb1, comb2->rest, 1); | |
2747 | } | |
2748 | ||
2749 | /* Splits EXPR into an affine combination of parts. */ | |
2750 | ||
2751 | static void | |
2752 | tree_to_aff_combination (tree expr, tree type, | |
2753 | struct affine_tree_combination *comb) | |
2754 | { | |
2755 | struct affine_tree_combination tmp; | |
2756 | enum tree_code code; | |
2757 | tree cst, core, toffset; | |
2758 | HOST_WIDE_INT bitpos, bitsize; | |
2759 | enum machine_mode mode; | |
2760 | int unsignedp, volatilep; | |
2761 | ||
2762 | STRIP_NOPS (expr); | |
2763 | ||
2764 | code = TREE_CODE (expr); | |
2765 | switch (code) | |
2766 | { | |
2767 | case INTEGER_CST: | |
2768 | aff_combination_const (comb, type, int_cst_value (expr)); | |
2769 | return; | |
2770 | ||
2771 | case PLUS_EXPR: | |
2772 | case MINUS_EXPR: | |
2773 | tree_to_aff_combination (TREE_OPERAND (expr, 0), type, comb); | |
2774 | tree_to_aff_combination (TREE_OPERAND (expr, 1), type, &tmp); | |
2775 | if (code == MINUS_EXPR) | |
2776 | aff_combination_scale (&tmp, -1); | |
2777 | aff_combination_add (comb, &tmp); | |
2778 | return; | |
2779 | ||
2780 | case MULT_EXPR: | |
2781 | cst = TREE_OPERAND (expr, 1); | |
2782 | if (TREE_CODE (cst) != INTEGER_CST) | |
2783 | break; | |
2784 | tree_to_aff_combination (TREE_OPERAND (expr, 0), type, comb); | |
2785 | aff_combination_scale (comb, int_cst_value (cst)); | |
2786 | return; | |
2787 | ||
2788 | case NEGATE_EXPR: | |
2789 | tree_to_aff_combination (TREE_OPERAND (expr, 0), type, comb); | |
2790 | aff_combination_scale (comb, -1); | |
2791 | return; | |
2792 | ||
2793 | case ADDR_EXPR: | |
2794 | core = get_inner_reference (TREE_OPERAND (expr, 0), &bitsize, &bitpos, | |
2795 | &toffset, &mode, &unsignedp, &volatilep, | |
2796 | false); | |
2797 | if (bitpos % BITS_PER_UNIT != 0) | |
2798 | break; | |
2799 | aff_combination_const (comb, type, bitpos / BITS_PER_UNIT); | |
d5dc1717 | 2800 | core = build_fold_addr_expr (core); |
9be872b7 ZD |
2801 | if (TREE_CODE (core) == ADDR_EXPR) |
2802 | aff_combination_add_elt (comb, core, 1); | |
2803 | else | |
2804 | { | |
2805 | tree_to_aff_combination (core, type, &tmp); | |
2806 | aff_combination_add (comb, &tmp); | |
2807 | } | |
2808 | if (toffset) | |
2809 | { | |
2810 | tree_to_aff_combination (toffset, type, &tmp); | |
2811 | aff_combination_add (comb, &tmp); | |
2812 | } | |
2813 | return; | |
2814 | ||
2815 | default: | |
2816 | break; | |
2817 | } | |
2818 | ||
2819 | aff_combination_elt (comb, type, expr); | |
2820 | } | |
2821 | ||
2822 | /* Creates EXPR + ELT * SCALE in TYPE. MASK is the mask for width of TYPE. */ | |
2823 | ||
2824 | static tree | |
2825 | add_elt_to_tree (tree expr, tree type, tree elt, unsigned HOST_WIDE_INT scale, | |
2826 | unsigned HOST_WIDE_INT mask) | |
2827 | { | |
2828 | enum tree_code code; | |
2829 | ||
2830 | scale &= mask; | |
2831 | elt = fold_convert (type, elt); | |
2832 | ||
2833 | if (scale == 1) | |
2834 | { | |
2835 | if (!expr) | |
2836 | return elt; | |
2837 | ||
2838 | return fold_build2 (PLUS_EXPR, type, expr, elt); | |
2839 | } | |
2840 | ||
2841 | if (scale == mask) | |
2842 | { | |
2843 | if (!expr) | |
2844 | return fold_build1 (NEGATE_EXPR, type, elt); | |
2845 | ||
2846 | return fold_build2 (MINUS_EXPR, type, expr, elt); | |
2847 | } | |
2848 | ||
2849 | if (!expr) | |
2850 | return fold_build2 (MULT_EXPR, type, elt, | |
2851 | build_int_cst_type (type, scale)); | |
2852 | ||
2853 | if ((scale | (mask >> 1)) == mask) | |
2854 | { | |
2855 | /* Scale is negative. */ | |
2856 | code = MINUS_EXPR; | |
2857 | scale = (-scale) & mask; | |
2858 | } | |
2859 | else | |
2860 | code = PLUS_EXPR; | |
2861 | ||
2862 | elt = fold_build2 (MULT_EXPR, type, elt, | |
2863 | build_int_cst_type (type, scale)); | |
2864 | return fold_build2 (code, type, expr, elt); | |
2865 | } | |
2866 | ||
ac182688 ZD |
2867 | /* Copies the tree elements of COMB to ensure that they are not shared. */ |
2868 | ||
2869 | static void | |
2870 | unshare_aff_combination (struct affine_tree_combination *comb) | |
2871 | { | |
2872 | unsigned i; | |
2873 | ||
2874 | for (i = 0; i < comb->n; i++) | |
2875 | comb->elts[i] = unshare_expr (comb->elts[i]); | |
2876 | if (comb->rest) | |
2877 | comb->rest = unshare_expr (comb->rest); | |
2878 | } | |
2879 | ||
9be872b7 ZD |
2880 | /* Makes tree from the affine combination COMB. */ |
2881 | ||
2882 | static tree | |
2883 | aff_combination_to_tree (struct affine_tree_combination *comb) | |
2884 | { | |
2885 | tree type = comb->type; | |
2886 | tree expr = comb->rest; | |
2887 | unsigned i; | |
2888 | unsigned HOST_WIDE_INT off, sgn; | |
2889 | ||
ac182688 ZD |
2890 | /* Handle the special case produced by get_computation_aff when |
2891 | the type does not fit in HOST_WIDE_INT. */ | |
2892 | if (comb->n == 0 && comb->offset == 0) | |
2893 | return fold_convert (type, expr); | |
2894 | ||
9be872b7 ZD |
2895 | gcc_assert (comb->n == MAX_AFF_ELTS || comb->rest == NULL_TREE); |
2896 | ||
2897 | for (i = 0; i < comb->n; i++) | |
2898 | expr = add_elt_to_tree (expr, type, comb->elts[i], comb->coefs[i], | |
2899 | comb->mask); | |
2900 | ||
2901 | if ((comb->offset | (comb->mask >> 1)) == comb->mask) | |
2902 | { | |
2903 | /* Offset is negative. */ | |
2904 | off = (-comb->offset) & comb->mask; | |
2905 | sgn = comb->mask; | |
2906 | } | |
2907 | else | |
2908 | { | |
2909 | off = comb->offset; | |
2910 | sgn = 1; | |
2911 | } | |
2912 | return add_elt_to_tree (expr, type, build_int_cst_type (type, off), sgn, | |
2913 | comb->mask); | |
2914 | } | |
2915 | ||
8b11a64c | 2916 | /* Determines the expression by that USE is expressed from induction variable |
ac182688 ZD |
2917 | CAND at statement AT in LOOP. The expression is stored in a decomposed |
2918 | form into AFF. Returns false if USE cannot be expressed using CAND. */ | |
8b11a64c | 2919 | |
ac182688 ZD |
2920 | static bool |
2921 | get_computation_aff (struct loop *loop, | |
2922 | struct iv_use *use, struct iv_cand *cand, tree at, | |
2923 | struct affine_tree_combination *aff) | |
8b11a64c | 2924 | { |
2f4675b4 ZD |
2925 | tree ubase = use->iv->base; |
2926 | tree ustep = use->iv->step; | |
2927 | tree cbase = cand->iv->base; | |
2928 | tree cstep = cand->iv->step; | |
8b11a64c ZD |
2929 | tree utype = TREE_TYPE (ubase), ctype = TREE_TYPE (cbase); |
2930 | tree uutype; | |
2931 | tree expr, delta; | |
2932 | tree ratio; | |
2933 | unsigned HOST_WIDE_INT ustepi, cstepi; | |
2934 | HOST_WIDE_INT ratioi; | |
ac182688 | 2935 | struct affine_tree_combination cbase_aff, expr_aff; |
c456a94a | 2936 | tree cstep_orig = cstep, ustep_orig = ustep; |
8b11a64c ZD |
2937 | |
2938 | if (TYPE_PRECISION (utype) > TYPE_PRECISION (ctype)) | |
2939 | { | |
2940 | /* We do not have a precision to express the values of use. */ | |
ac182688 | 2941 | return false; |
8b11a64c ZD |
2942 | } |
2943 | ||
2944 | expr = var_at_stmt (loop, cand, at); | |
2945 | ||
2946 | if (TREE_TYPE (expr) != ctype) | |
2947 | { | |
2948 | /* This may happen with the original ivs. */ | |
2949 | expr = fold_convert (ctype, expr); | |
2950 | } | |
2951 | ||
2952 | if (TYPE_UNSIGNED (utype)) | |
2953 | uutype = utype; | |
2954 | else | |
2955 | { | |
2956 | uutype = unsigned_type_for (utype); | |
2957 | ubase = fold_convert (uutype, ubase); | |
2958 | ustep = fold_convert (uutype, ustep); | |
2959 | } | |
2960 | ||
2961 | if (uutype != ctype) | |
2962 | { | |
2963 | expr = fold_convert (uutype, expr); | |
2964 | cbase = fold_convert (uutype, cbase); | |
2965 | cstep = fold_convert (uutype, cstep); | |
c456a94a ZD |
2966 | |
2967 | /* If the conversion is not noop, we must take it into account when | |
2968 | considering the value of the step. */ | |
2969 | if (TYPE_PRECISION (utype) < TYPE_PRECISION (ctype)) | |
2970 | cstep_orig = cstep; | |
8b11a64c ZD |
2971 | } |
2972 | ||
c456a94a ZD |
2973 | if (cst_and_fits_in_hwi (cstep_orig) |
2974 | && cst_and_fits_in_hwi (ustep_orig)) | |
9be872b7 | 2975 | { |
c456a94a ZD |
2976 | ustepi = int_cst_value (ustep_orig); |
2977 | cstepi = int_cst_value (cstep_orig); | |
8b11a64c | 2978 | |
9be872b7 ZD |
2979 | if (!divide (TYPE_PRECISION (uutype), ustepi, cstepi, &ratioi)) |
2980 | { | |
2981 | /* TODO maybe consider case when ustep divides cstep and the ratio is | |
2982 | a power of 2 (so that the division is fast to execute)? We would | |
2983 | need to be much more careful with overflows etc. then. */ | |
ac182688 | 2984 | return false; |
9be872b7 | 2985 | } |
8b11a64c | 2986 | |
9be872b7 ZD |
2987 | ratio = build_int_cst_type (uutype, ratioi); |
2988 | } | |
2989 | else | |
8b11a64c | 2990 | { |
c456a94a | 2991 | ratio = constant_multiple_of (uutype, ustep_orig, cstep_orig); |
9be872b7 | 2992 | if (!ratio) |
ac182688 | 2993 | return false; |
9be872b7 ZD |
2994 | |
2995 | /* Ratioi is only used to detect special cases when the multiplicative | |
2996 | factor is 1 or -1, so if we cannot convert ratio to HOST_WIDE_INT, | |
2997 | we may set it to 0. We prefer cst_and_fits_in_hwi/int_cst_value | |
2998 | to integer_onep/integer_all_onesp, since the former ignores | |
2999 | TREE_OVERFLOW. */ | |
3000 | if (cst_and_fits_in_hwi (ratio)) | |
3001 | ratioi = int_cst_value (ratio); | |
3002 | else if (integer_onep (ratio)) | |
3003 | ratioi = 1; | |
3004 | else if (integer_all_onesp (ratio)) | |
3005 | ratioi = -1; | |
3006 | else | |
3007 | ratioi = 0; | |
8b11a64c ZD |
3008 | } |
3009 | ||
3010 | /* We may need to shift the value if we are after the increment. */ | |
3011 | if (stmt_after_increment (loop, cand, at)) | |
987b67bc | 3012 | cbase = fold_build2 (PLUS_EXPR, uutype, cbase, cstep); |
8b11a64c | 3013 | |
b0a168b6 ZD |
3014 | /* use = ubase - ratio * cbase + ratio * var. |
3015 | ||
3016 | In general case ubase + ratio * (var - cbase) could be better (one less | |
3017 | multiplication), but often it is possible to eliminate redundant parts | |
3018 | of computations from (ubase - ratio * cbase) term, and if it does not | |
3019 | happen, fold is able to apply the distributive law to obtain this form | |
3020 | anyway. */ | |
8b11a64c | 3021 | |
ac182688 | 3022 | if (TYPE_PRECISION (uutype) > HOST_BITS_PER_WIDE_INT) |
8b11a64c | 3023 | { |
ac182688 ZD |
3024 | /* Let's compute in trees and just return the result in AFF. This case |
3025 | should not be very common, and fold itself is not that bad either, | |
3026 | so making the aff. functions more complicated to handle this case | |
3027 | is not that urgent. */ | |
3028 | if (ratioi == 1) | |
3029 | { | |
3030 | delta = fold_build2 (MINUS_EXPR, uutype, ubase, cbase); | |
3031 | expr = fold_build2 (PLUS_EXPR, uutype, expr, delta); | |
3032 | } | |
3033 | else if (ratioi == -1) | |
3034 | { | |
3035 | delta = fold_build2 (PLUS_EXPR, uutype, ubase, cbase); | |
3036 | expr = fold_build2 (MINUS_EXPR, uutype, delta, expr); | |
3037 | } | |
9be872b7 ZD |
3038 | else |
3039 | { | |
ac182688 ZD |
3040 | delta = fold_build2 (MULT_EXPR, uutype, cbase, ratio); |
3041 | delta = fold_build2 (MINUS_EXPR, uutype, ubase, delta); | |
3042 | expr = fold_build2 (MULT_EXPR, uutype, ratio, expr); | |
3043 | expr = fold_build2 (PLUS_EXPR, uutype, delta, expr); | |
9be872b7 | 3044 | } |
ac182688 ZD |
3045 | |
3046 | aff->type = uutype; | |
3047 | aff->n = 0; | |
3048 | aff->offset = 0; | |
3049 | aff->mask = 0; | |
3050 | aff->rest = expr; | |
3051 | return true; | |
8b11a64c | 3052 | } |
8b11a64c | 3053 | |
ac182688 ZD |
3054 | /* If we got here, the types fits in HOST_WIDE_INT, thus it must be |
3055 | possible to compute ratioi. */ | |
3056 | gcc_assert (ratioi); | |
3057 | ||
3058 | tree_to_aff_combination (ubase, uutype, aff); | |
3059 | tree_to_aff_combination (cbase, uutype, &cbase_aff); | |
3060 | tree_to_aff_combination (expr, uutype, &expr_aff); | |
3061 | aff_combination_scale (&cbase_aff, -ratioi); | |
3062 | aff_combination_scale (&expr_aff, ratioi); | |
3063 | aff_combination_add (aff, &cbase_aff); | |
3064 | aff_combination_add (aff, &expr_aff); | |
3065 | ||
3066 | return true; | |
3067 | } | |
3068 | ||
3069 | /* Determines the expression by that USE is expressed from induction variable | |
3070 | CAND at statement AT in LOOP. The computation is unshared. */ | |
3071 | ||
3072 | static tree | |
3073 | get_computation_at (struct loop *loop, | |
3074 | struct iv_use *use, struct iv_cand *cand, tree at) | |
3075 | { | |
3076 | struct affine_tree_combination aff; | |
3077 | tree type = TREE_TYPE (use->iv->base); | |
3078 | ||
3079 | if (!get_computation_aff (loop, use, cand, at, &aff)) | |
3080 | return NULL_TREE; | |
3081 | unshare_aff_combination (&aff); | |
3082 | return fold_convert (type, aff_combination_to_tree (&aff)); | |
8b11a64c ZD |
3083 | } |
3084 | ||
3085 | /* Determines the expression by that USE is expressed from induction variable | |
ac182688 | 3086 | CAND in LOOP. The computation is unshared. */ |
8b11a64c ZD |
3087 | |
3088 | static tree | |
3089 | get_computation (struct loop *loop, struct iv_use *use, struct iv_cand *cand) | |
3090 | { | |
3091 | return get_computation_at (loop, use, cand, use->stmt); | |
3092 | } | |
3093 | ||
8b11a64c ZD |
3094 | /* Returns cost of addition in MODE. */ |
3095 | ||
3096 | static unsigned | |
3097 | add_cost (enum machine_mode mode) | |
3098 | { | |
3099 | static unsigned costs[NUM_MACHINE_MODES]; | |
3100 | rtx seq; | |
3101 | unsigned cost; | |
3102 | ||
3103 | if (costs[mode]) | |
3104 | return costs[mode]; | |
3105 | ||
3106 | start_sequence (); | |
3107 | force_operand (gen_rtx_fmt_ee (PLUS, mode, | |
03daa27a ZD |
3108 | gen_raw_REG (mode, LAST_VIRTUAL_REGISTER + 1), |
3109 | gen_raw_REG (mode, LAST_VIRTUAL_REGISTER + 2)), | |
8b11a64c ZD |
3110 | NULL_RTX); |
3111 | seq = get_insns (); | |
3112 | end_sequence (); | |
3113 | ||
3114 | cost = seq_cost (seq); | |
3115 | if (!cost) | |
3116 | cost = 1; | |
3117 | ||
3118 | costs[mode] = cost; | |
3119 | ||
3120 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3121 | fprintf (dump_file, "Addition in %s costs %d\n", | |
3122 | GET_MODE_NAME (mode), cost); | |
3123 | return cost; | |
3124 | } | |
3125 | ||
3126 | /* Entry in a hashtable of already known costs for multiplication. */ | |
3127 | struct mbc_entry | |
3128 | { | |
3129 | HOST_WIDE_INT cst; /* The constant to multiply by. */ | |
3130 | enum machine_mode mode; /* In mode. */ | |
3131 | unsigned cost; /* The cost. */ | |
3132 | }; | |
3133 | ||
3134 | /* Counts hash value for the ENTRY. */ | |
3135 | ||
3136 | static hashval_t | |
3137 | mbc_entry_hash (const void *entry) | |
3138 | { | |
3139 | const struct mbc_entry *e = entry; | |
3140 | ||
3141 | return 57 * (hashval_t) e->mode + (hashval_t) (e->cst % 877); | |
3142 | } | |
3143 | ||
3144 | /* Compares the hash table entries ENTRY1 and ENTRY2. */ | |
3145 | ||
3146 | static int | |
3147 | mbc_entry_eq (const void *entry1, const void *entry2) | |
3148 | { | |
3149 | const struct mbc_entry *e1 = entry1; | |
3150 | const struct mbc_entry *e2 = entry2; | |
3151 | ||
3152 | return (e1->mode == e2->mode | |
3153 | && e1->cst == e2->cst); | |
3154 | } | |
3155 | ||
3156 | /* Returns cost of multiplication by constant CST in MODE. */ | |
3157 | ||
ac182688 | 3158 | unsigned |
8b11a64c ZD |
3159 | multiply_by_cost (HOST_WIDE_INT cst, enum machine_mode mode) |
3160 | { | |
3161 | static htab_t costs; | |
3162 | struct mbc_entry **cached, act; | |
3163 | rtx seq; | |
3164 | unsigned cost; | |
3165 | ||
3166 | if (!costs) | |
3167 | costs = htab_create (100, mbc_entry_hash, mbc_entry_eq, free); | |
3168 | ||
3169 | act.mode = mode; | |
3170 | act.cst = cst; | |
3171 | cached = (struct mbc_entry **) htab_find_slot (costs, &act, INSERT); | |
3172 | if (*cached) | |
3173 | return (*cached)->cost; | |
3174 | ||
5ed6ace5 | 3175 | *cached = XNEW (struct mbc_entry); |
8b11a64c ZD |
3176 | (*cached)->mode = mode; |
3177 | (*cached)->cst = cst; | |
3178 | ||
3179 | start_sequence (); | |
03daa27a ZD |
3180 | expand_mult (mode, gen_raw_REG (mode, LAST_VIRTUAL_REGISTER + 1), |
3181 | gen_int_mode (cst, mode), NULL_RTX, 0); | |
8b11a64c ZD |
3182 | seq = get_insns (); |
3183 | end_sequence (); | |
3184 | ||
3185 | cost = seq_cost (seq); | |
3186 | ||
3187 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3188 | fprintf (dump_file, "Multiplication by %d in %s costs %d\n", | |
3189 | (int) cst, GET_MODE_NAME (mode), cost); | |
3190 | ||
3191 | (*cached)->cost = cost; | |
3192 | ||
3193 | return cost; | |
3194 | } | |
3195 | ||
ac182688 ZD |
3196 | /* Returns true if multiplying by RATIO is allowed in address. */ |
3197 | ||
3198 | bool | |
3199 | multiplier_allowed_in_address_p (HOST_WIDE_INT ratio) | |
3200 | { | |
3201 | #define MAX_RATIO 128 | |
3202 | static sbitmap valid_mult; | |
3203 | ||
3204 | if (!valid_mult) | |
3205 | { | |
03daa27a | 3206 | rtx reg1 = gen_raw_REG (Pmode, LAST_VIRTUAL_REGISTER + 1); |
ac182688 ZD |
3207 | rtx addr; |
3208 | HOST_WIDE_INT i; | |
3209 | ||
3210 | valid_mult = sbitmap_alloc (2 * MAX_RATIO + 1); | |
3211 | sbitmap_zero (valid_mult); | |
3212 | addr = gen_rtx_fmt_ee (MULT, Pmode, reg1, NULL_RTX); | |
3213 | for (i = -MAX_RATIO; i <= MAX_RATIO; i++) | |
3214 | { | |
3215 | XEXP (addr, 1) = gen_int_mode (i, Pmode); | |
3216 | if (memory_address_p (Pmode, addr)) | |
3217 | SET_BIT (valid_mult, i + MAX_RATIO); | |
3218 | } | |
3219 | ||
3220 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3221 | { | |
3222 | fprintf (dump_file, " allowed multipliers:"); | |
3223 | for (i = -MAX_RATIO; i <= MAX_RATIO; i++) | |
3224 | if (TEST_BIT (valid_mult, i + MAX_RATIO)) | |
3225 | fprintf (dump_file, " %d", (int) i); | |
3226 | fprintf (dump_file, "\n"); | |
3227 | fprintf (dump_file, "\n"); | |
3228 | } | |
3229 | } | |
3230 | ||
3231 | if (ratio > MAX_RATIO || ratio < -MAX_RATIO) | |
3232 | return false; | |
3233 | ||
3234 | return TEST_BIT (valid_mult, ratio + MAX_RATIO); | |
3235 | } | |
3236 | ||
8b11a64c ZD |
3237 | /* Returns cost of address in shape symbol + var + OFFSET + RATIO * index. |
3238 | If SYMBOL_PRESENT is false, symbol is omitted. If VAR_PRESENT is false, | |
3239 | variable is omitted. The created memory accesses MODE. | |
3240 | ||
3241 | TODO -- there must be some better way. This all is quite crude. */ | |
3242 | ||
3243 | static unsigned | |
3244 | get_address_cost (bool symbol_present, bool var_present, | |
3245 | unsigned HOST_WIDE_INT offset, HOST_WIDE_INT ratio) | |
3246 | { | |
ac182688 | 3247 | static bool initialized = false; |
8b11a64c ZD |
3248 | static HOST_WIDE_INT rat, off; |
3249 | static HOST_WIDE_INT min_offset, max_offset; | |
3250 | static unsigned costs[2][2][2][2]; | |
3251 | unsigned cost, acost; | |
3252 | rtx seq, addr, base; | |
3253 | bool offset_p, ratio_p; | |
3254 | rtx reg1; | |
3255 | HOST_WIDE_INT s_offset; | |
3256 | unsigned HOST_WIDE_INT mask; | |
3257 | unsigned bits; | |
3258 | ||
ac182688 | 3259 | if (!initialized) |
8b11a64c ZD |
3260 | { |
3261 | HOST_WIDE_INT i; | |
ac182688 | 3262 | initialized = true; |
8b11a64c | 3263 | |
03daa27a | 3264 | reg1 = gen_raw_REG (Pmode, LAST_VIRTUAL_REGISTER + 1); |
8b11a64c ZD |
3265 | |
3266 | addr = gen_rtx_fmt_ee (PLUS, Pmode, reg1, NULL_RTX); | |
3267 | for (i = 1; i <= 1 << 20; i <<= 1) | |
3268 | { | |
03daa27a | 3269 | XEXP (addr, 1) = gen_int_mode (i, Pmode); |
8b11a64c ZD |
3270 | if (!memory_address_p (Pmode, addr)) |
3271 | break; | |
3272 | } | |
3273 | max_offset = i >> 1; | |
3274 | off = max_offset; | |
3275 | ||
3276 | for (i = 1; i <= 1 << 20; i <<= 1) | |
3277 | { | |
03daa27a | 3278 | XEXP (addr, 1) = gen_int_mode (-i, Pmode); |
8b11a64c ZD |
3279 | if (!memory_address_p (Pmode, addr)) |
3280 | break; | |
3281 | } | |
3282 | min_offset = -(i >> 1); | |
3283 | ||
3284 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
3285 | { | |
3286 | fprintf (dump_file, "get_address_cost:\n"); | |
3287 | fprintf (dump_file, " min offset %d\n", (int) min_offset); | |
3288 | fprintf (dump_file, " max offset %d\n", (int) max_offset); | |
3289 | } | |
3290 | ||
8b11a64c | 3291 | rat = 1; |
ac182688 ZD |
3292 | for (i = 2; i <= MAX_RATIO; i++) |
3293 | if (multiplier_allowed_in_address_p (i)) | |
3294 | { | |
3295 | rat = i; | |
3296 | break; | |
3297 | } | |
8b11a64c ZD |
3298 | } |
3299 | ||
3300 | bits = GET_MODE_BITSIZE (Pmode); | |
3301 | mask = ~(~(unsigned HOST_WIDE_INT) 0 << (bits - 1) << 1); | |
3302 | offset &= mask; | |
3303 | if ((offset >> (bits - 1) & 1)) | |
3304 | offset |= ~mask; | |
3305 | s_offset = offset; | |
3306 | ||
3307 | cost = 0; | |
a85a9024 UW |
3308 | offset_p = (s_offset != 0 |
3309 | && min_offset <= s_offset && s_offset <= max_offset); | |
8b11a64c | 3310 | ratio_p = (ratio != 1 |
ac182688 | 3311 | && multiplier_allowed_in_address_p (ratio)); |
8b11a64c ZD |
3312 | |
3313 | if (ratio != 1 && !ratio_p) | |
3314 | cost += multiply_by_cost (ratio, Pmode); | |
3315 | ||
3316 | if (s_offset && !offset_p && !symbol_present) | |
3317 | { | |
3318 | cost += add_cost (Pmode); | |
3319 | var_present = true; | |
3320 | } | |
3321 | ||
3322 | acost = costs[symbol_present][var_present][offset_p][ratio_p]; | |
3323 | if (!acost) | |
3324 | { | |
85a43114 | 3325 | int old_cse_not_expected; |
8b11a64c ZD |
3326 | acost = 0; |
3327 | ||
03daa27a ZD |
3328 | addr = gen_raw_REG (Pmode, LAST_VIRTUAL_REGISTER + 1); |
3329 | reg1 = gen_raw_REG (Pmode, LAST_VIRTUAL_REGISTER + 2); | |
8b11a64c | 3330 | if (ratio_p) |
03daa27a | 3331 | addr = gen_rtx_fmt_ee (MULT, Pmode, addr, gen_int_mode (rat, Pmode)); |
8b11a64c | 3332 | |
a85a9024 | 3333 | if (var_present) |
7299dbfb | 3334 | addr = gen_rtx_fmt_ee (PLUS, Pmode, addr, reg1); |
a85a9024 | 3335 | |
8b11a64c ZD |
3336 | if (symbol_present) |
3337 | { | |
3338 | base = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup ("")); | |
3339 | if (offset_p) | |
3340 | base = gen_rtx_fmt_e (CONST, Pmode, | |
3341 | gen_rtx_fmt_ee (PLUS, Pmode, | |
3342 | base, | |
03daa27a | 3343 | gen_int_mode (off, Pmode))); |
8b11a64c ZD |
3344 | } |
3345 | else if (offset_p) | |
03daa27a | 3346 | base = gen_int_mode (off, Pmode); |
8b11a64c ZD |
3347 | else |
3348 | base = NULL_RTX; | |
3349 | ||
3350 | if (base) | |
7299dbfb | 3351 | addr = gen_rtx_fmt_ee (PLUS, Pmode, addr, base); |
8b11a64c ZD |
3352 | |
3353 | start_sequence (); | |
85a43114 ZD |
3354 | /* To avoid splitting addressing modes, pretend that no cse will |
3355 | follow. */ | |
3356 | old_cse_not_expected = cse_not_expected; | |
3357 | cse_not_expected = true; | |
8b11a64c | 3358 | addr = memory_address (Pmode, addr); |
85a43114 | 3359 | cse_not_expected = old_cse_not_expected; |
8b11a64c ZD |
3360 | seq = get_insns (); |
3361 | end_sequence (); | |
3362 | ||
3363 | acost = seq_cost (seq); | |
3364 | acost += address_cost (addr, Pmode); | |
3365 | ||
3366 | if (!acost) | |
3367 | acost = 1; | |
3368 | costs[symbol_present][var_present][offset_p][ratio_p] = acost; | |
3369 | } | |
3370 | ||
3371 | return cost + acost; | |
3372 | } | |
8b11a64c | 3373 | |
3ac01fde ZD |
3374 | /* Estimates cost of forcing expression EXPR into a variable. */ |
3375 | ||
3376 | unsigned | |
3377 | force_expr_to_var_cost (tree expr) | |
8b11a64c ZD |
3378 | { |
3379 | static bool costs_initialized = false; | |
3380 | static unsigned integer_cost; | |
3381 | static unsigned symbol_cost; | |
3382 | static unsigned address_cost; | |
7299dbfb ZD |
3383 | tree op0, op1; |
3384 | unsigned cost0, cost1, cost; | |
3385 | enum machine_mode mode; | |
8b11a64c ZD |
3386 | |
3387 | if (!costs_initialized) | |
3388 | { | |
3389 | tree var = create_tmp_var_raw (integer_type_node, "test_var"); | |
3390 | rtx x = gen_rtx_MEM (DECL_MODE (var), | |
3391 | gen_rtx_SYMBOL_REF (Pmode, "test_var")); | |
3392 | tree addr; | |
3393 | tree type = build_pointer_type (integer_type_node); | |
3394 | ||
ff5e9a94 SP |
3395 | integer_cost = computation_cost (build_int_cst (integer_type_node, |
3396 | 2000)); | |
8b11a64c ZD |
3397 | |
3398 | SET_DECL_RTL (var, x); | |
3399 | TREE_STATIC (var) = 1; | |
3400 | addr = build1 (ADDR_EXPR, type, var); | |
3401 | symbol_cost = computation_cost (addr) + 1; | |
3402 | ||
3403 | address_cost | |
3404 | = computation_cost (build2 (PLUS_EXPR, type, | |
3405 | addr, | |
ff5e9a94 | 3406 | build_int_cst (type, 2000))) + 1; |
8b11a64c ZD |
3407 | if (dump_file && (dump_flags & TDF_DETAILS)) |
3408 | { | |
3ac01fde | 3409 | fprintf (dump_file, "force_expr_to_var_cost:\n"); |
8b11a64c ZD |
3410 | fprintf (dump_file, " integer %d\n", (int) integer_cost); |
3411 | fprintf (dump_file, " symbol %d\n", (int) symbol_cost); | |
3412 | fprintf (dump_file, " address %d\n", (int) address_cost); | |
3413 | fprintf (dump_file, " other %d\n", (int) target_spill_cost); | |
3414 | fprintf (dump_file, "\n"); | |
3415 | } | |
3416 | ||
3417 | costs_initialized = true; | |
3418 | } | |
3419 | ||
f5e2738c ZD |
3420 | STRIP_NOPS (expr); |
3421 | ||
8b11a64c ZD |
3422 | if (SSA_VAR_P (expr)) |
3423 | return 0; | |
3424 | ||
3425 | if (TREE_INVARIANT (expr)) | |
3426 | { | |
3427 | if (TREE_CODE (expr) == INTEGER_CST) | |
3428 | return integer_cost; | |
3429 | ||
3430 | if (TREE_CODE (expr) == ADDR_EXPR) | |
3431 | { | |
3432 | tree obj = TREE_OPERAND (expr, 0); | |
3433 | ||
3434 | if (TREE_CODE (obj) == VAR_DECL | |
3435 | || TREE_CODE (obj) == PARM_DECL | |
3436 | || TREE_CODE (obj) == RESULT_DECL) | |
3437 | return symbol_cost; | |
3438 | } | |
3439 | ||
3440 | return address_cost; | |
3441 | } | |
3442 | ||
7299dbfb ZD |
3443 | switch (TREE_CODE (expr)) |
3444 | { | |
3445 | case PLUS_EXPR: | |
3446 | case MINUS_EXPR: | |
3447 | case MULT_EXPR: | |
3448 | op0 = TREE_OPERAND (expr, 0); | |
3449 | op1 = TREE_OPERAND (expr, 1); | |
f5e2738c ZD |
3450 | STRIP_NOPS (op0); |
3451 | STRIP_NOPS (op1); | |
7299dbfb ZD |
3452 | |
3453 | if (is_gimple_val (op0)) | |
3454 | cost0 = 0; | |
3455 | else | |
3ac01fde | 3456 | cost0 = force_expr_to_var_cost (op0); |
7299dbfb ZD |
3457 | |
3458 | if (is_gimple_val (op1)) | |
3459 | cost1 = 0; | |
3460 | else | |
3ac01fde | 3461 | cost1 = force_expr_to_var_cost (op1); |
7299dbfb ZD |
3462 | |
3463 | break; | |
3464 | ||
3465 | default: | |
3466 | /* Just an arbitrary value, FIXME. */ | |
3467 | return target_spill_cost; | |
3468 | } | |
3469 | ||
3470 | mode = TYPE_MODE (TREE_TYPE (expr)); | |
3471 | switch (TREE_CODE (expr)) | |
3472 | { | |
3473 | case PLUS_EXPR: | |
3474 | case MINUS_EXPR: | |
3475 | cost = add_cost (mode); | |
3476 | break; | |
3477 | ||
3478 | case MULT_EXPR: | |
3479 | if (cst_and_fits_in_hwi (op0)) | |
3480 | cost = multiply_by_cost (int_cst_value (op0), mode); | |
3481 | else if (cst_and_fits_in_hwi (op1)) | |
3482 | cost = multiply_by_cost (int_cst_value (op1), mode); | |
3483 | else | |
3484 | return target_spill_cost; | |
3485 | break; | |
3486 | ||
3487 | default: | |
3488 | gcc_unreachable (); | |
3489 | } | |
3490 | ||
3491 | cost += cost0; | |
3492 | cost += cost1; | |
3493 | ||
3494 | /* Bound the cost by target_spill_cost. The parts of complicated | |
3495 | computations often are either loop invariant or at least can | |
3496 | be shared between several iv uses, so letting this grow without | |
3497 | limits would not give reasonable results. */ | |
3498 | return cost < target_spill_cost ? cost : target_spill_cost; | |
8b11a64c ZD |
3499 | } |
3500 | ||
3ac01fde ZD |
3501 | /* Estimates cost of forcing EXPR into a variable. DEPENDS_ON is a set of the |
3502 | invariants the computation depends on. */ | |
3503 | ||
3504 | static unsigned | |
3505 | force_var_cost (struct ivopts_data *data, | |
3506 | tree expr, bitmap *depends_on) | |
3507 | { | |
3508 | if (depends_on) | |
3509 | { | |
3510 | fd_ivopts_data = data; | |
3511 | walk_tree (&expr, find_depends, depends_on, NULL); | |
3512 | } | |
3513 | ||
3514 | return force_expr_to_var_cost (expr); | |
3515 | } | |
3516 | ||
8b11a64c ZD |
3517 | /* Estimates cost of expressing address ADDR as var + symbol + offset. The |
3518 | value of offset is added to OFFSET, SYMBOL_PRESENT and VAR_PRESENT are set | |
3519 | to false if the corresponding part is missing. DEPENDS_ON is a set of the | |
3520 | invariants the computation depends on. */ | |
3521 | ||
3522 | static unsigned | |
3523 | split_address_cost (struct ivopts_data *data, | |
3524 | tree addr, bool *symbol_present, bool *var_present, | |
3525 | unsigned HOST_WIDE_INT *offset, bitmap *depends_on) | |
3526 | { | |
2f4675b4 ZD |
3527 | tree core; |
3528 | HOST_WIDE_INT bitsize; | |
3529 | HOST_WIDE_INT bitpos; | |
3530 | tree toffset; | |
3531 | enum machine_mode mode; | |
3532 | int unsignedp, volatilep; | |
3533 | ||
3534 | core = get_inner_reference (addr, &bitsize, &bitpos, &toffset, &mode, | |
2614034e | 3535 | &unsignedp, &volatilep, false); |
8b11a64c | 3536 | |
2f4675b4 ZD |
3537 | if (toffset != 0 |
3538 | || bitpos % BITS_PER_UNIT != 0 | |
3539 | || TREE_CODE (core) != VAR_DECL) | |
8b11a64c ZD |
3540 | { |
3541 | *symbol_present = false; | |
3542 | *var_present = true; | |
3543 | fd_ivopts_data = data; | |
3544 | walk_tree (&addr, find_depends, depends_on, NULL); | |
3545 | return target_spill_cost; | |
2f4675b4 ZD |
3546 | } |
3547 | ||
3548 | *offset += bitpos / BITS_PER_UNIT; | |
8b11a64c ZD |
3549 | if (TREE_STATIC (core) |
3550 | || DECL_EXTERNAL (core)) | |
3551 | { | |
3552 | *symbol_present = true; | |
3553 | *var_present = false; | |
3554 | return 0; | |
3555 | } | |
3556 | ||
3557 | *symbol_present = false; | |
3558 | *var_present = true; | |
3559 | return 0; | |
3560 | } | |
3561 | ||
3562 | /* Estimates cost of expressing difference of addresses E1 - E2 as | |
3563 | var + symbol + offset. The value of offset is added to OFFSET, | |
3564 | SYMBOL_PRESENT and VAR_PRESENT are set to false if the corresponding | |
3565 | part is missing. DEPENDS_ON is a set of the invariants the computation | |
3566 | depends on. */ | |
3567 | ||
3568 | static unsigned | |
3569 | ptr_difference_cost (struct ivopts_data *data, | |
3570 | tree e1, tree e2, bool *symbol_present, bool *var_present, | |
3571 | unsigned HOST_WIDE_INT *offset, bitmap *depends_on) | |
3572 | { | |
2f4675b4 | 3573 | HOST_WIDE_INT diff = 0; |
8b11a64c ZD |
3574 | unsigned cost; |
3575 | ||
1e128c5f | 3576 | gcc_assert (TREE_CODE (e1) == ADDR_EXPR); |
8b11a64c | 3577 | |
7299dbfb | 3578 | if (ptr_difference_const (e1, e2, &diff)) |
8b11a64c ZD |
3579 | { |
3580 | *offset += diff; | |
3581 | *symbol_present = false; | |
3582 | *var_present = false; | |
3583 | return 0; | |
3584 | } | |
3585 | ||
3586 | if (e2 == integer_zero_node) | |
3587 | return split_address_cost (data, TREE_OPERAND (e1, 0), | |
3588 | symbol_present, var_present, offset, depends_on); | |
3589 | ||
3590 | *symbol_present = false; | |
3591 | *var_present = true; | |
3592 | ||
3593 | cost = force_var_cost (data, e1, depends_on); | |
3594 | cost += force_var_cost (data, e2, depends_on); | |
3595 | cost += add_cost (Pmode); | |
3596 | ||
3597 | return cost; | |
3598 | } | |
3599 | ||
3600 | /* Estimates cost of expressing difference E1 - E2 as | |
3601 | var + symbol + offset. The value of offset is added to OFFSET, | |
3602 | SYMBOL_PRESENT and VAR_PRESENT are set to false if the corresponding | |
3603 | part is missing. DEPENDS_ON is a set of the invariants the computation | |
3604 | depends on. */ | |
3605 | ||
3606 | static unsigned | |
3607 | difference_cost (struct ivopts_data *data, | |
3608 | tree e1, tree e2, bool *symbol_present, bool *var_present, | |
3609 | unsigned HOST_WIDE_INT *offset, bitmap *depends_on) | |
3610 | { | |
3611 | unsigned cost; | |
3612 | enum machine_mode mode = TYPE_MODE (TREE_TYPE (e1)); | |
f5e2738c ZD |
3613 | unsigned HOST_WIDE_INT off1, off2; |
3614 | ||
9be872b7 ZD |
3615 | e1 = strip_offset (e1, &off1); |
3616 | e2 = strip_offset (e2, &off2); | |
f5e2738c | 3617 | *offset += off1 - off2; |
8b11a64c | 3618 | |
f5e2738c ZD |
3619 | STRIP_NOPS (e1); |
3620 | STRIP_NOPS (e2); | |
8b11a64c ZD |
3621 | |
3622 | if (TREE_CODE (e1) == ADDR_EXPR) | |
3623 | return ptr_difference_cost (data, e1, e2, symbol_present, var_present, offset, | |
3624 | depends_on); | |
3625 | *symbol_present = false; | |
3626 | ||
3627 | if (operand_equal_p (e1, e2, 0)) | |
3628 | { | |
3629 | *var_present = false; | |
3630 | return 0; | |
3631 | } | |
3632 | *var_present = true; | |
3633 | if (zero_p (e2)) | |
3634 | return force_var_cost (data, e1, depends_on); | |
3635 | ||
3636 | if (zero_p (e1)) | |
3637 | { | |
3638 | cost = force_var_cost (data, e2, depends_on); | |
3639 | cost += multiply_by_cost (-1, mode); | |
3640 | ||
3641 | return cost; | |
3642 | } | |
3643 | ||
3644 | cost = force_var_cost (data, e1, depends_on); | |
3645 | cost += force_var_cost (data, e2, depends_on); | |
3646 | cost += add_cost (mode); | |
3647 | ||
3648 | return cost; | |
3649 | } | |
3650 | ||
3651 | /* Determines the cost of the computation by that USE is expressed | |
3652 | from induction variable CAND. If ADDRESS_P is true, we just need | |
3653 | to create an address from it, otherwise we want to get it into | |
3654 | register. A set of invariants we depend on is stored in | |
3655 | DEPENDS_ON. AT is the statement at that the value is computed. */ | |
3656 | ||
3657 | static unsigned | |
3658 | get_computation_cost_at (struct ivopts_data *data, | |
3659 | struct iv_use *use, struct iv_cand *cand, | |
3660 | bool address_p, bitmap *depends_on, tree at) | |
3661 | { | |
3662 | tree ubase = use->iv->base, ustep = use->iv->step; | |
3663 | tree cbase, cstep; | |
3664 | tree utype = TREE_TYPE (ubase), ctype; | |
3665 | unsigned HOST_WIDE_INT ustepi, cstepi, offset = 0; | |
3666 | HOST_WIDE_INT ratio, aratio; | |
3667 | bool var_present, symbol_present; | |
3668 | unsigned cost = 0, n_sums; | |
3669 | ||
3670 | *depends_on = NULL; | |
3671 | ||
3672 | /* Only consider real candidates. */ | |
3673 | if (!cand->iv) | |
3674 | return INFTY; | |
3675 | ||
3676 | cbase = cand->iv->base; | |
3677 | cstep = cand->iv->step; | |
3678 | ctype = TREE_TYPE (cbase); | |
3679 | ||
3680 | if (TYPE_PRECISION (utype) > TYPE_PRECISION (ctype)) | |
3681 | { | |
3682 | /* We do not have a precision to express the values of use. */ | |
3683 | return INFTY; | |
3684 | } | |
3685 | ||
e6845c23 ZD |
3686 | if (address_p) |
3687 | { | |
3688 | /* Do not try to express address of an object with computation based | |
3689 | on address of a different object. This may cause problems in rtl | |
3690 | level alias analysis (that does not expect this to be happening, | |
3691 | as this is illegal in C), and would be unlikely to be useful | |
3692 | anyway. */ | |
3693 | if (use->iv->base_object | |
3694 | && cand->iv->base_object | |
3695 | && !operand_equal_p (use->iv->base_object, cand->iv->base_object, 0)) | |
3696 | return INFTY; | |
3697 | } | |
3698 | ||
8b11a64c ZD |
3699 | if (TYPE_PRECISION (utype) != TYPE_PRECISION (ctype)) |
3700 | { | |
3701 | /* TODO -- add direct handling of this case. */ | |
3702 | goto fallback; | |
3703 | } | |
3704 | ||
9be872b7 ZD |
3705 | /* CSTEPI is removed from the offset in case statement is after the |
3706 | increment. If the step is not constant, we use zero instead. | |
1e1def1c | 3707 | This is a bit imprecise (there is the extra addition), but |
9be872b7 ZD |
3708 | redundancy elimination is likely to transform the code so that |
3709 | it uses value of the variable before increment anyway, | |
3710 | so it is not that much unrealistic. */ | |
3711 | if (cst_and_fits_in_hwi (cstep)) | |
3712 | cstepi = int_cst_value (cstep); | |
3713 | else | |
3714 | cstepi = 0; | |
3715 | ||
3716 | if (cst_and_fits_in_hwi (ustep) | |
3717 | && cst_and_fits_in_hwi (cstep)) | |
3718 | { | |
3719 | ustepi = int_cst_value (ustep); | |
3720 | ||
3721 | if (!divide (TYPE_PRECISION (utype), ustepi, cstepi, &ratio)) | |
3722 | return INFTY; | |
3723 | } | |
3724 | else | |
3725 | { | |
3726 | tree rat; | |
3727 | ||
3728 | rat = constant_multiple_of (utype, ustep, cstep); | |
3729 | ||
3730 | if (!rat) | |
3731 | return INFTY; | |
3732 | ||
3733 | if (cst_and_fits_in_hwi (rat)) | |
3734 | ratio = int_cst_value (rat); | |
3735 | else if (integer_onep (rat)) | |
3736 | ratio = 1; | |
3737 | else if (integer_all_onesp (rat)) | |
3738 | ratio = -1; | |
3739 | else | |
3740 | return INFTY; | |
3741 | } | |
8b11a64c ZD |
3742 | |
3743 | /* use = ubase + ratio * (var - cbase). If either cbase is a constant | |
3744 | or ratio == 1, it is better to handle this like | |
3745 | ||
3746 | ubase - ratio * cbase + ratio * var | |
3747 | ||
3748 | (also holds in the case ratio == -1, TODO. */ | |
3749 | ||
9be872b7 | 3750 | if (cst_and_fits_in_hwi (cbase)) |
8b11a64c ZD |
3751 | { |
3752 | offset = - ratio * int_cst_value (cbase); | |
3753 | cost += difference_cost (data, | |
3754 | ubase, integer_zero_node, | |
3755 | &symbol_present, &var_present, &offset, | |
3756 | depends_on); | |
3757 | } | |
3758 | else if (ratio == 1) | |
3759 | { | |
3760 | cost += difference_cost (data, | |
3761 | ubase, cbase, | |
3762 | &symbol_present, &var_present, &offset, | |
3763 | depends_on); | |
3764 | } | |
3765 | else | |
3766 | { | |
3767 | cost += force_var_cost (data, cbase, depends_on); | |
3768 | cost += add_cost (TYPE_MODE (ctype)); | |
3769 | cost += difference_cost (data, | |
3770 | ubase, integer_zero_node, | |
3771 | &symbol_present, &var_present, &offset, | |
3772 | depends_on); | |
3773 | } | |
3774 | ||
3775 | /* If we are after the increment, the value of the candidate is higher by | |
3776 | one iteration. */ | |
3777 | if (stmt_after_increment (data->current_loop, cand, at)) | |
3778 | offset -= ratio * cstepi; | |
3779 | ||
3780 | /* Now the computation is in shape symbol + var1 + const + ratio * var2. | |
3781 | (symbol/var/const parts may be omitted). If we are looking for an address, | |
3782 | find the cost of addressing this. */ | |
3783 | if (address_p) | |
7299dbfb | 3784 | return cost + get_address_cost (symbol_present, var_present, offset, ratio); |
8b11a64c ZD |
3785 | |
3786 | /* Otherwise estimate the costs for computing the expression. */ | |
3787 | aratio = ratio > 0 ? ratio : -ratio; | |
3788 | if (!symbol_present && !var_present && !offset) | |
3789 | { | |
3790 | if (ratio != 1) | |
3791 | cost += multiply_by_cost (ratio, TYPE_MODE (ctype)); | |
3792 | ||
3793 | return cost; | |
3794 | } | |
3795 | ||
3796 | if (aratio != 1) | |
3797 | cost += multiply_by_cost (aratio, TYPE_MODE (ctype)); | |
3798 | ||
3799 | n_sums = 1; | |
3800 | if (var_present | |
3801 | /* Symbol + offset should be compile-time computable. */ | |
3802 | && (symbol_present || offset)) | |
3803 | n_sums++; | |
3804 | ||
3805 | return cost + n_sums * add_cost (TYPE_MODE (ctype)); | |
3806 | ||
3807 | fallback: | |
3808 | { | |
3809 | /* Just get the expression, expand it and measure the cost. */ | |
3810 | tree comp = get_computation_at (data->current_loop, use, cand, at); | |
3811 | ||
3812 | if (!comp) | |
3813 | return INFTY; | |
3814 | ||
3815 | if (address_p) | |
3816 | comp = build1 (INDIRECT_REF, TREE_TYPE (TREE_TYPE (comp)), comp); | |
3817 | ||
3818 | return computation_cost (comp); | |
3819 | } | |
3820 | } | |
3821 | ||
3822 | /* Determines the cost of the computation by that USE is expressed | |
3823 | from induction variable CAND. If ADDRESS_P is true, we just need | |
3824 | to create an address from it, otherwise we want to get it into | |
3825 | register. A set of invariants we depend on is stored in | |
3826 | DEPENDS_ON. */ | |
3827 | ||
3828 | static unsigned | |
3829 | get_computation_cost (struct ivopts_data *data, | |
3830 | struct iv_use *use, struct iv_cand *cand, | |
3831 | bool address_p, bitmap *depends_on) | |
3832 | { | |
3833 | return get_computation_cost_at (data, | |
3834 | use, cand, address_p, depends_on, use->stmt); | |
3835 | } | |
3836 | ||
3837 | /* Determines cost of basing replacement of USE on CAND in a generic | |
3838 | expression. */ | |
3839 | ||
b1b02be2 | 3840 | static bool |
8b11a64c ZD |
3841 | determine_use_iv_cost_generic (struct ivopts_data *data, |
3842 | struct iv_use *use, struct iv_cand *cand) | |
3843 | { | |
3844 | bitmap depends_on; | |
eec5fec9 ZD |
3845 | unsigned cost; |
3846 | ||
3847 | /* The simple case first -- if we need to express value of the preserved | |
3848 | original biv, the cost is 0. This also prevents us from counting the | |
3849 | cost of increment twice -- once at this use and once in the cost of | |
3850 | the candidate. */ | |
3851 | if (cand->pos == IP_ORIGINAL | |
3852 | && cand->incremented_at == use->stmt) | |
3853 | { | |
f5f12961 | 3854 | set_use_iv_cost (data, use, cand, 0, NULL, NULL_TREE); |
eec5fec9 ZD |
3855 | return true; |
3856 | } | |
8b11a64c | 3857 | |
eec5fec9 | 3858 | cost = get_computation_cost (data, use, cand, false, &depends_on); |
f5f12961 | 3859 | set_use_iv_cost (data, use, cand, cost, depends_on, NULL_TREE); |
b1b02be2 ZD |
3860 | |
3861 | return cost != INFTY; | |
8b11a64c ZD |
3862 | } |
3863 | ||
3864 | /* Determines cost of basing replacement of USE on CAND in an address. */ | |
3865 | ||
b1b02be2 | 3866 | static bool |
8b11a64c ZD |
3867 | determine_use_iv_cost_address (struct ivopts_data *data, |
3868 | struct iv_use *use, struct iv_cand *cand) | |
3869 | { | |
3870 | bitmap depends_on; | |
3871 | unsigned cost = get_computation_cost (data, use, cand, true, &depends_on); | |
3872 | ||
f5f12961 | 3873 | set_use_iv_cost (data, use, cand, cost, depends_on, NULL_TREE); |
b1b02be2 ZD |
3874 | |
3875 | return cost != INFTY; | |
8b11a64c ZD |
3876 | } |
3877 | ||
3878 | /* Computes value of induction variable IV in iteration NITER. */ | |
3879 | ||
3880 | static tree | |
3881 | iv_value (struct iv *iv, tree niter) | |
3882 | { | |
3883 | tree val; | |
3884 | tree type = TREE_TYPE (iv->base); | |
3885 | ||
3886 | niter = fold_convert (type, niter); | |
987b67bc | 3887 | val = fold_build2 (MULT_EXPR, type, iv->step, niter); |
8b11a64c | 3888 | |
987b67bc | 3889 | return fold_build2 (PLUS_EXPR, type, iv->base, val); |
8b11a64c ZD |
3890 | } |
3891 | ||
3892 | /* Computes value of candidate CAND at position AT in iteration NITER. */ | |
3893 | ||
3894 | static tree | |
3895 | cand_value_at (struct loop *loop, struct iv_cand *cand, tree at, tree niter) | |
3896 | { | |
3897 | tree val = iv_value (cand->iv, niter); | |
3898 | tree type = TREE_TYPE (cand->iv->base); | |
3899 | ||
3900 | if (stmt_after_increment (loop, cand, at)) | |
987b67bc | 3901 | val = fold_build2 (PLUS_EXPR, type, val, cand->iv->step); |
8b11a64c ZD |
3902 | |
3903 | return val; | |
3904 | } | |
3905 | ||
ca4c3169 ZD |
3906 | /* Returns period of induction variable iv. */ |
3907 | ||
3908 | static tree | |
3909 | iv_period (struct iv *iv) | |
3910 | { | |
3911 | tree step = iv->step, period, type; | |
3912 | tree pow2div; | |
3913 | ||
3914 | gcc_assert (step && TREE_CODE (step) == INTEGER_CST); | |
3915 | ||
3916 | /* Period of the iv is gcd (step, type range). Since type range is power | |
3917 | of two, it suffices to determine the maximum power of two that divides | |
3918 | step. */ | |
3919 | pow2div = num_ending_zeros (step); | |
3920 | type = unsigned_type_for (TREE_TYPE (step)); | |
3921 | ||
3922 | period = build_low_bits_mask (type, | |
3923 | (TYPE_PRECISION (type) | |
3924 | - tree_low_cst (pow2div, 1))); | |
3925 | ||
3926 | return period; | |
3927 | } | |
3928 | ||
f5f12961 ZD |
3929 | /* Returns the comparison operator used when eliminating the iv USE. */ |
3930 | ||
3931 | static enum tree_code | |
3932 | iv_elimination_compare (struct ivopts_data *data, struct iv_use *use) | |
3933 | { | |
3934 | struct loop *loop = data->current_loop; | |
3935 | basic_block ex_bb; | |
3936 | edge exit; | |
3937 | ||
3938 | ex_bb = bb_for_stmt (use->stmt); | |
3939 | exit = EDGE_SUCC (ex_bb, 0); | |
3940 | if (flow_bb_inside_loop_p (loop, exit->dest)) | |
3941 | exit = EDGE_SUCC (ex_bb, 1); | |
3942 | ||
3943 | return (exit->flags & EDGE_TRUE_VALUE ? EQ_EXPR : NE_EXPR); | |
3944 | } | |
3945 | ||
8b11a64c | 3946 | /* Check whether it is possible to express the condition in USE by comparison |
f5f12961 | 3947 | of candidate CAND. If so, store the value compared with to BOUND. */ |
8b11a64c ZD |
3948 | |
3949 | static bool | |
ca4c3169 | 3950 | may_eliminate_iv (struct ivopts_data *data, |
f5f12961 | 3951 | struct iv_use *use, struct iv_cand *cand, tree *bound) |
8b11a64c | 3952 | { |
e6845c23 | 3953 | basic_block ex_bb; |
8b11a64c | 3954 | edge exit; |
ca4c3169 ZD |
3955 | tree nit, nit_type; |
3956 | tree wider_type, period, per_type; | |
3957 | struct loop *loop = data->current_loop; | |
e6845c23 | 3958 | |
9be872b7 ZD |
3959 | if (TREE_CODE (cand->iv->step) != INTEGER_CST) |
3960 | return false; | |
3961 | ||
e6845c23 ZD |
3962 | /* For now works only for exits that dominate the loop latch. TODO -- extend |
3963 | for other conditions inside loop body. */ | |
3964 | ex_bb = bb_for_stmt (use->stmt); | |
3965 | if (use->stmt != last_stmt (ex_bb) | |
3966 | || TREE_CODE (use->stmt) != COND_EXPR) | |
8b11a64c | 3967 | return false; |
e6845c23 | 3968 | if (!dominated_by_p (CDI_DOMINATORS, loop->latch, ex_bb)) |
8b11a64c ZD |
3969 | return false; |
3970 | ||
e6845c23 ZD |
3971 | exit = EDGE_SUCC (ex_bb, 0); |
3972 | if (flow_bb_inside_loop_p (loop, exit->dest)) | |
3973 | exit = EDGE_SUCC (ex_bb, 1); | |
3974 | if (flow_bb_inside_loop_p (loop, exit->dest)) | |
3975 | return false; | |
3976 | ||
dcccd88d ZD |
3977 | nit = niter_for_exit (data, exit); |
3978 | if (!nit) | |
8b11a64c ZD |
3979 | return false; |
3980 | ||
ca4c3169 | 3981 | nit_type = TREE_TYPE (nit); |
8b11a64c | 3982 | |
ca4c3169 ZD |
3983 | /* Determine whether we may use the variable to test whether niter iterations |
3984 | elapsed. This is the case iff the period of the induction variable is | |
3985 | greater than the number of iterations. */ | |
3986 | period = iv_period (cand->iv); | |
3987 | if (!period) | |
8b11a64c | 3988 | return false; |
ca4c3169 ZD |
3989 | per_type = TREE_TYPE (period); |
3990 | ||
3991 | wider_type = TREE_TYPE (period); | |
3992 | if (TYPE_PRECISION (nit_type) < TYPE_PRECISION (per_type)) | |
3993 | wider_type = per_type; | |
3994 | else | |
3995 | wider_type = nit_type; | |
8b11a64c | 3996 | |
987b67bc KH |
3997 | if (!integer_nonzerop (fold_build2 (GE_EXPR, boolean_type_node, |
3998 | fold_convert (wider_type, period), | |
3999 | fold_convert (wider_type, nit)))) | |
8b11a64c ZD |
4000 | return false; |
4001 | ||
ca4c3169 | 4002 | *bound = cand_value_at (loop, cand, use->stmt, nit); |
8b11a64c ZD |
4003 | return true; |
4004 | } | |
4005 | ||
4006 | /* Determines cost of basing replacement of USE on CAND in a condition. */ | |
4007 | ||
b1b02be2 | 4008 | static bool |
8b11a64c ZD |
4009 | determine_use_iv_cost_condition (struct ivopts_data *data, |
4010 | struct iv_use *use, struct iv_cand *cand) | |
4011 | { | |
f5f12961 ZD |
4012 | tree bound = NULL_TREE, op, cond; |
4013 | bitmap depends_on = NULL; | |
4014 | unsigned cost; | |
8b11a64c ZD |
4015 | |
4016 | /* Only consider real candidates. */ | |
4017 | if (!cand->iv) | |
4018 | { | |
f5f12961 | 4019 | set_use_iv_cost (data, use, cand, INFTY, NULL, NULL_TREE); |
b1b02be2 | 4020 | return false; |
8b11a64c ZD |
4021 | } |
4022 | ||
f5f12961 | 4023 | if (may_eliminate_iv (data, use, cand, &bound)) |
8b11a64c | 4024 | { |
f5f12961 | 4025 | cost = force_var_cost (data, bound, &depends_on); |
8b11a64c | 4026 | |
f5f12961 | 4027 | set_use_iv_cost (data, use, cand, cost, depends_on, bound); |
b1b02be2 | 4028 | return cost != INFTY; |
8b11a64c ZD |
4029 | } |
4030 | ||
4031 | /* The induction variable elimination failed; just express the original | |
4032 | giv. If it is compared with an invariant, note that we cannot get | |
4033 | rid of it. */ | |
f5f12961 ZD |
4034 | cost = get_computation_cost (data, use, cand, false, &depends_on); |
4035 | ||
4036 | cond = *use->op_p; | |
4037 | if (TREE_CODE (cond) != SSA_NAME) | |
8b11a64c | 4038 | { |
f5f12961 ZD |
4039 | op = TREE_OPERAND (cond, 0); |
4040 | if (TREE_CODE (op) == SSA_NAME && !zero_p (get_iv (data, op)->step)) | |
4041 | op = TREE_OPERAND (cond, 1); | |
4042 | if (TREE_CODE (op) == SSA_NAME) | |
4043 | { | |
4044 | op = get_iv (data, op)->base; | |
4045 | fd_ivopts_data = data; | |
4046 | walk_tree (&op, find_depends, &depends_on, NULL); | |
4047 | } | |
8b11a64c ZD |
4048 | } |
4049 | ||
f5f12961 ZD |
4050 | set_use_iv_cost (data, use, cand, cost, depends_on, NULL); |
4051 | return cost != INFTY; | |
8b11a64c ZD |
4052 | } |
4053 | ||
b1b02be2 ZD |
4054 | /* Determines cost of basing replacement of USE on CAND. Returns false |
4055 | if USE cannot be based on CAND. */ | |
8b11a64c | 4056 | |
b1b02be2 | 4057 | static bool |
8b11a64c ZD |
4058 | determine_use_iv_cost (struct ivopts_data *data, |
4059 | struct iv_use *use, struct iv_cand *cand) | |
4060 | { | |
4061 | switch (use->type) | |
4062 | { | |
4063 | case USE_NONLINEAR_EXPR: | |
b1b02be2 | 4064 | return determine_use_iv_cost_generic (data, use, cand); |
8b11a64c | 4065 | |
8b11a64c | 4066 | case USE_ADDRESS: |
b1b02be2 | 4067 | return determine_use_iv_cost_address (data, use, cand); |
8b11a64c ZD |
4068 | |
4069 | case USE_COMPARE: | |
b1b02be2 | 4070 | return determine_use_iv_cost_condition (data, use, cand); |
8b11a64c ZD |
4071 | |
4072 | default: | |
1e128c5f | 4073 | gcc_unreachable (); |
8b11a64c ZD |
4074 | } |
4075 | } | |
4076 | ||
4077 | /* Determines costs of basing the use of the iv on an iv candidate. */ | |
4078 | ||
4079 | static void | |
4080 | determine_use_iv_costs (struct ivopts_data *data) | |
4081 | { | |
4082 | unsigned i, j; | |
4083 | struct iv_use *use; | |
4084 | struct iv_cand *cand; | |
8bdbfff5 | 4085 | bitmap to_clear = BITMAP_ALLOC (NULL); |
8b11a64c ZD |
4086 | |
4087 | alloc_use_cost_map (data); | |
4088 | ||
8b11a64c ZD |
4089 | for (i = 0; i < n_iv_uses (data); i++) |
4090 | { | |
4091 | use = iv_use (data, i); | |
4092 | ||
4093 | if (data->consider_all_candidates) | |
4094 | { | |
4095 | for (j = 0; j < n_iv_cands (data); j++) | |
4096 | { | |
4097 | cand = iv_cand (data, j); | |
4098 | determine_use_iv_cost (data, use, cand); | |
4099 | } | |
4100 | } | |
4101 | else | |
4102 | { | |
87c476a2 ZD |
4103 | bitmap_iterator bi; |
4104 | ||
4105 | EXECUTE_IF_SET_IN_BITMAP (use->related_cands, 0, j, bi) | |
8b11a64c ZD |
4106 | { |
4107 | cand = iv_cand (data, j); | |
b1b02be2 ZD |
4108 | if (!determine_use_iv_cost (data, use, cand)) |
4109 | bitmap_set_bit (to_clear, j); | |
87c476a2 | 4110 | } |
b1b02be2 ZD |
4111 | |
4112 | /* Remove the candidates for that the cost is infinite from | |
4113 | the list of related candidates. */ | |
4114 | bitmap_and_compl_into (use->related_cands, to_clear); | |
4115 | bitmap_clear (to_clear); | |
8b11a64c ZD |
4116 | } |
4117 | } | |
4118 | ||
8bdbfff5 | 4119 | BITMAP_FREE (to_clear); |
b1b02be2 | 4120 | |
8b11a64c ZD |
4121 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4122 | { | |
4123 | fprintf (dump_file, "Use-candidate costs:\n"); | |
4124 | ||
4125 | for (i = 0; i < n_iv_uses (data); i++) | |
4126 | { | |
4127 | use = iv_use (data, i); | |
4128 | ||
4129 | fprintf (dump_file, "Use %d:\n", i); | |
4130 | fprintf (dump_file, " cand\tcost\tdepends on\n"); | |
4131 | for (j = 0; j < use->n_map_members; j++) | |
4132 | { | |
4133 | if (!use->cost_map[j].cand | |
4134 | || use->cost_map[j].cost == INFTY) | |
4135 | continue; | |
4136 | ||
4137 | fprintf (dump_file, " %d\t%d\t", | |
4138 | use->cost_map[j].cand->id, | |
4139 | use->cost_map[j].cost); | |
4140 | if (use->cost_map[j].depends_on) | |
4141 | bitmap_print (dump_file, | |
4142 | use->cost_map[j].depends_on, "",""); | |
4143 | fprintf (dump_file, "\n"); | |
4144 | } | |
4145 | ||
4146 | fprintf (dump_file, "\n"); | |
4147 | } | |
4148 | fprintf (dump_file, "\n"); | |
4149 | } | |
4150 | } | |
4151 | ||
4152 | /* Determines cost of the candidate CAND. */ | |
4153 | ||
4154 | static void | |
4155 | determine_iv_cost (struct ivopts_data *data, struct iv_cand *cand) | |
4156 | { | |
4157 | unsigned cost_base, cost_step; | |
4366cf6d | 4158 | tree base; |
8b11a64c ZD |
4159 | |
4160 | if (!cand->iv) | |
4161 | { | |
4162 | cand->cost = 0; | |
4163 | return; | |
4164 | } | |
4165 | ||
4166 | /* There are two costs associated with the candidate -- its increment | |
4167 | and its initialization. The second is almost negligible for any loop | |
4168 | that rolls enough, so we take it just very little into account. */ | |
4169 | ||
4170 | base = cand->iv->base; | |
4171 | cost_base = force_var_cost (data, base, NULL); | |
4172 | cost_step = add_cost (TYPE_MODE (TREE_TYPE (base))); | |
4173 | ||
4174 | cand->cost = cost_step + cost_base / AVG_LOOP_NITER (current_loop); | |
4175 | ||
cf5d1802 ZD |
4176 | /* Prefer the original iv unless we may gain something by replacing it; |
4177 | this is not really relevant for artificial ivs created by other | |
4178 | passes. */ | |
4179 | if (cand->pos == IP_ORIGINAL | |
4180 | && !DECL_ARTIFICIAL (SSA_NAME_VAR (cand->var_before))) | |
8b11a64c ZD |
4181 | cand->cost--; |
4182 | ||
4183 | /* Prefer not to insert statements into latch unless there are some | |
4184 | already (so that we do not create unnecessary jumps). */ | |
4366cf6d ZD |
4185 | if (cand->pos == IP_END |
4186 | && empty_block_p (ip_end_pos (data->current_loop))) | |
4187 | cand->cost++; | |
8b11a64c ZD |
4188 | } |
4189 | ||
4190 | /* Determines costs of computation of the candidates. */ | |
4191 | ||
4192 | static void | |
4193 | determine_iv_costs (struct ivopts_data *data) | |
4194 | { | |
4195 | unsigned i; | |
4196 | ||
4197 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4198 | { | |
4199 | fprintf (dump_file, "Candidate costs:\n"); | |
4200 | fprintf (dump_file, " cand\tcost\n"); | |
4201 | } | |
4202 | ||
4203 | for (i = 0; i < n_iv_cands (data); i++) | |
4204 | { | |
4205 | struct iv_cand *cand = iv_cand (data, i); | |
4206 | ||
4207 | determine_iv_cost (data, cand); | |
4208 | ||
4209 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4210 | fprintf (dump_file, " %d\t%d\n", i, cand->cost); | |
4211 | } | |
4212 | ||
4213 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4214 | fprintf (dump_file, "\n"); | |
4215 | } | |
4216 | ||
4217 | /* Calculates cost for having SIZE induction variables. */ | |
4218 | ||
4219 | static unsigned | |
4220 | ivopts_global_cost_for_size (struct ivopts_data *data, unsigned size) | |
4221 | { | |
9a2ef6b8 | 4222 | return global_cost_for_size (size, data->regs_used, n_iv_uses (data)); |
8b11a64c ZD |
4223 | } |
4224 | ||
4225 | /* For each size of the induction variable set determine the penalty. */ | |
4226 | ||
4227 | static void | |
4228 | determine_set_costs (struct ivopts_data *data) | |
4229 | { | |
4230 | unsigned j, n; | |
4231 | tree phi, op; | |
4232 | struct loop *loop = data->current_loop; | |
87c476a2 | 4233 | bitmap_iterator bi; |
8b11a64c ZD |
4234 | |
4235 | /* We use the following model (definitely improvable, especially the | |
4236 | cost function -- TODO): | |
4237 | ||
4238 | We estimate the number of registers available (using MD data), name it A. | |
4239 | ||
4240 | We estimate the number of registers used by the loop, name it U. This | |
4241 | number is obtained as the number of loop phi nodes (not counting virtual | |
4242 | registers and bivs) + the number of variables from outside of the loop. | |
4243 | ||
4244 | We set a reserve R (free regs that are used for temporary computations, | |
4245 | etc.). For now the reserve is a constant 3. | |
4246 | ||
4247 | Let I be the number of induction variables. | |
4248 | ||
4249 | -- if U + I + R <= A, the cost is I * SMALL_COST (just not to encourage | |
4250 | make a lot of ivs without a reason). | |
4251 | -- if A - R < U + I <= A, the cost is I * PRES_COST | |
4252 | -- if U + I > A, the cost is I * PRES_COST and | |
4253 | number of uses * SPILL_COST * (U + I - A) / (U + I) is added. */ | |
4254 | ||
4255 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4256 | { | |
4257 | fprintf (dump_file, "Global costs:\n"); | |
4258 | fprintf (dump_file, " target_avail_regs %d\n", target_avail_regs); | |
4259 | fprintf (dump_file, " target_small_cost %d\n", target_small_cost); | |
4260 | fprintf (dump_file, " target_pres_cost %d\n", target_pres_cost); | |
4261 | fprintf (dump_file, " target_spill_cost %d\n", target_spill_cost); | |
4262 | } | |
4263 | ||
4264 | n = 0; | |
bb29d951 | 4265 | for (phi = phi_nodes (loop->header); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
4266 | { |
4267 | op = PHI_RESULT (phi); | |
4268 | ||
4269 | if (!is_gimple_reg (op)) | |
4270 | continue; | |
4271 | ||
4272 | if (get_iv (data, op)) | |
4273 | continue; | |
4274 | ||
4275 | n++; | |
4276 | } | |
4277 | ||
87c476a2 | 4278 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, j, bi) |
8b11a64c ZD |
4279 | { |
4280 | struct version_info *info = ver_info (data, j); | |
4281 | ||
4282 | if (info->inv_id && info->has_nonlin_use) | |
4283 | n++; | |
87c476a2 | 4284 | } |
8b11a64c | 4285 | |
9a2ef6b8 | 4286 | data->regs_used = n; |
8b11a64c ZD |
4287 | if (dump_file && (dump_flags & TDF_DETAILS)) |
4288 | fprintf (dump_file, " regs_used %d\n", n); | |
4289 | ||
4290 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
4291 | { | |
4292 | fprintf (dump_file, " cost for size:\n"); | |
4293 | fprintf (dump_file, " ivs\tcost\n"); | |
4294 | for (j = 0; j <= 2 * target_avail_regs; j++) | |
4295 | fprintf (dump_file, " %d\t%d\n", j, | |
4296 | ivopts_global_cost_for_size (data, j)); | |
4297 | fprintf (dump_file, "\n"); | |
4298 | } | |
4299 | } | |
4300 | ||
b1b02be2 | 4301 | /* Returns true if A is a cheaper cost pair than B. */ |
8b11a64c | 4302 | |
b1b02be2 ZD |
4303 | static bool |
4304 | cheaper_cost_pair (struct cost_pair *a, struct cost_pair *b) | |
8b11a64c | 4305 | { |
b1b02be2 ZD |
4306 | if (!a) |
4307 | return false; | |
8b11a64c | 4308 | |
b1b02be2 ZD |
4309 | if (!b) |
4310 | return true; | |
4311 | ||
4312 | if (a->cost < b->cost) | |
4313 | return true; | |
4314 | ||
4315 | if (a->cost > b->cost) | |
4316 | return false; | |
4317 | ||
4318 | /* In case the costs are the same, prefer the cheaper candidate. */ | |
4319 | if (a->cand->cost < b->cand->cost) | |
4320 | return true; | |
4321 | ||
4322 | return false; | |
4323 | } | |
4324 | ||
4325 | /* Computes the cost field of IVS structure. */ | |
4326 | ||
4327 | static void | |
4328 | iv_ca_recount_cost (struct ivopts_data *data, struct iv_ca *ivs) | |
4329 | { | |
4330 | unsigned cost = 0; | |
4331 | ||
4332 | cost += ivs->cand_use_cost; | |
4333 | cost += ivs->cand_cost; | |
4334 | cost += ivopts_global_cost_for_size (data, ivs->n_regs); | |
4335 | ||
4336 | ivs->cost = cost; | |
4337 | } | |
4338 | ||
9be872b7 ZD |
4339 | /* Remove invariants in set INVS to set IVS. */ |
4340 | ||
4341 | static void | |
4342 | iv_ca_set_remove_invariants (struct iv_ca *ivs, bitmap invs) | |
4343 | { | |
4344 | bitmap_iterator bi; | |
4345 | unsigned iid; | |
4346 | ||
4347 | if (!invs) | |
4348 | return; | |
4349 | ||
4350 | EXECUTE_IF_SET_IN_BITMAP (invs, 0, iid, bi) | |
4351 | { | |
4352 | ivs->n_invariant_uses[iid]--; | |
4353 | if (ivs->n_invariant_uses[iid] == 0) | |
4354 | ivs->n_regs--; | |
4355 | } | |
4356 | } | |
4357 | ||
b1b02be2 ZD |
4358 | /* Set USE not to be expressed by any candidate in IVS. */ |
4359 | ||
4360 | static void | |
4361 | iv_ca_set_no_cp (struct ivopts_data *data, struct iv_ca *ivs, | |
4362 | struct iv_use *use) | |
4363 | { | |
9be872b7 | 4364 | unsigned uid = use->id, cid; |
b1b02be2 | 4365 | struct cost_pair *cp; |
b1b02be2 ZD |
4366 | |
4367 | cp = ivs->cand_for_use[uid]; | |
4368 | if (!cp) | |
4369 | return; | |
4370 | cid = cp->cand->id; | |
4371 | ||
4372 | ivs->bad_uses++; | |
4373 | ivs->cand_for_use[uid] = NULL; | |
4374 | ivs->n_cand_uses[cid]--; | |
4375 | ||
4376 | if (ivs->n_cand_uses[cid] == 0) | |
8b11a64c | 4377 | { |
b1b02be2 ZD |
4378 | bitmap_clear_bit (ivs->cands, cid); |
4379 | /* Do not count the pseudocandidates. */ | |
4380 | if (cp->cand->iv) | |
4381 | ivs->n_regs--; | |
36f5ada1 | 4382 | ivs->n_cands--; |
b1b02be2 | 4383 | ivs->cand_cost -= cp->cand->cost; |
9be872b7 ZD |
4384 | |
4385 | iv_ca_set_remove_invariants (ivs, cp->cand->depends_on); | |
b1b02be2 ZD |
4386 | } |
4387 | ||
4388 | ivs->cand_use_cost -= cp->cost; | |
4389 | ||
9be872b7 ZD |
4390 | iv_ca_set_remove_invariants (ivs, cp->depends_on); |
4391 | iv_ca_recount_cost (data, ivs); | |
4392 | } | |
4393 | ||
4394 | /* Add invariants in set INVS to set IVS. */ | |
80cad5fa | 4395 | |
9be872b7 ZD |
4396 | static void |
4397 | iv_ca_set_add_invariants (struct iv_ca *ivs, bitmap invs) | |
4398 | { | |
4399 | bitmap_iterator bi; | |
4400 | unsigned iid; | |
4401 | ||
4402 | if (!invs) | |
4403 | return; | |
4404 | ||
4405 | EXECUTE_IF_SET_IN_BITMAP (invs, 0, iid, bi) | |
b1b02be2 | 4406 | { |
9be872b7 ZD |
4407 | ivs->n_invariant_uses[iid]++; |
4408 | if (ivs->n_invariant_uses[iid] == 1) | |
4409 | ivs->n_regs++; | |
8b11a64c | 4410 | } |
b1b02be2 ZD |
4411 | } |
4412 | ||
4413 | /* Set cost pair for USE in set IVS to CP. */ | |
4414 | ||
4415 | static void | |
4416 | iv_ca_set_cp (struct ivopts_data *data, struct iv_ca *ivs, | |
4417 | struct iv_use *use, struct cost_pair *cp) | |
4418 | { | |
9be872b7 | 4419 | unsigned uid = use->id, cid; |
b1b02be2 ZD |
4420 | |
4421 | if (ivs->cand_for_use[uid] == cp) | |
4422 | return; | |
4423 | ||
4424 | if (ivs->cand_for_use[uid]) | |
4425 | iv_ca_set_no_cp (data, ivs, use); | |
4426 | ||
4427 | if (cp) | |
8b11a64c | 4428 | { |
b1b02be2 | 4429 | cid = cp->cand->id; |
8b11a64c | 4430 | |
b1b02be2 ZD |
4431 | ivs->bad_uses--; |
4432 | ivs->cand_for_use[uid] = cp; | |
4433 | ivs->n_cand_uses[cid]++; | |
4434 | if (ivs->n_cand_uses[cid] == 1) | |
8b11a64c | 4435 | { |
b1b02be2 ZD |
4436 | bitmap_set_bit (ivs->cands, cid); |
4437 | /* Do not count the pseudocandidates. */ | |
4438 | if (cp->cand->iv) | |
4439 | ivs->n_regs++; | |
36f5ada1 | 4440 | ivs->n_cands++; |
b1b02be2 | 4441 | ivs->cand_cost += cp->cand->cost; |
b1b02be2 | 4442 | |
9be872b7 | 4443 | iv_ca_set_add_invariants (ivs, cp->cand->depends_on); |
8b11a64c ZD |
4444 | } |
4445 | ||
9be872b7 ZD |
4446 | ivs->cand_use_cost += cp->cost; |
4447 | iv_ca_set_add_invariants (ivs, cp->depends_on); | |
b1b02be2 | 4448 | iv_ca_recount_cost (data, ivs); |
87c476a2 | 4449 | } |
b1b02be2 ZD |
4450 | } |
4451 | ||
4452 | /* Extend set IVS by expressing USE by some of the candidates in it | |
4453 | if possible. */ | |
4454 | ||
4455 | static void | |
4456 | iv_ca_add_use (struct ivopts_data *data, struct iv_ca *ivs, | |
4457 | struct iv_use *use) | |
4458 | { | |
4459 | struct cost_pair *best_cp = NULL, *cp; | |
4460 | bitmap_iterator bi; | |
4461 | unsigned i; | |
8b11a64c | 4462 | |
b1b02be2 ZD |
4463 | gcc_assert (ivs->upto >= use->id); |
4464 | ||
4465 | if (ivs->upto == use->id) | |
4466 | { | |
4467 | ivs->upto++; | |
4468 | ivs->bad_uses++; | |
4469 | } | |
8b11a64c | 4470 | |
b1b02be2 ZD |
4471 | EXECUTE_IF_SET_IN_BITMAP (ivs->cands, 0, i, bi) |
4472 | { | |
4473 | cp = get_use_iv_cost (data, use, iv_cand (data, i)); | |
8b11a64c | 4474 | |
b1b02be2 ZD |
4475 | if (cheaper_cost_pair (cp, best_cp)) |
4476 | best_cp = cp; | |
4477 | } | |
8b11a64c | 4478 | |
b1b02be2 | 4479 | iv_ca_set_cp (data, ivs, use, best_cp); |
8b11a64c ZD |
4480 | } |
4481 | ||
b1b02be2 | 4482 | /* Get cost for assignment IVS. */ |
8b11a64c ZD |
4483 | |
4484 | static unsigned | |
b1b02be2 ZD |
4485 | iv_ca_cost (struct iv_ca *ivs) |
4486 | { | |
4487 | return (ivs->bad_uses ? INFTY : ivs->cost); | |
4488 | } | |
4489 | ||
4490 | /* Returns true if all dependences of CP are among invariants in IVS. */ | |
4491 | ||
4492 | static bool | |
4493 | iv_ca_has_deps (struct iv_ca *ivs, struct cost_pair *cp) | |
8b11a64c ZD |
4494 | { |
4495 | unsigned i; | |
87c476a2 | 4496 | bitmap_iterator bi; |
8b11a64c | 4497 | |
b1b02be2 ZD |
4498 | if (!cp->depends_on) |
4499 | return true; | |
4500 | ||
4501 | EXECUTE_IF_SET_IN_BITMAP (cp->depends_on, 0, i, bi) | |
8b11a64c | 4502 | { |
b1b02be2 ZD |
4503 | if (ivs->n_invariant_uses[i] == 0) |
4504 | return false; | |
4505 | } | |
4506 | ||
4507 | return true; | |
4508 | } | |
4509 | ||
4510 | /* Creates change of expressing USE by NEW_CP instead of OLD_CP and chains | |
4511 | it before NEXT_CHANGE. */ | |
4512 | ||
4513 | static struct iv_ca_delta * | |
4514 | iv_ca_delta_add (struct iv_use *use, struct cost_pair *old_cp, | |
4515 | struct cost_pair *new_cp, struct iv_ca_delta *next_change) | |
4516 | { | |
5ed6ace5 | 4517 | struct iv_ca_delta *change = XNEW (struct iv_ca_delta); |
b1b02be2 ZD |
4518 | |
4519 | change->use = use; | |
4520 | change->old_cp = old_cp; | |
4521 | change->new_cp = new_cp; | |
4522 | change->next_change = next_change; | |
4523 | ||
4524 | return change; | |
4525 | } | |
4526 | ||
36f5ada1 | 4527 | /* Joins two lists of changes L1 and L2. Destructive -- old lists |
6c6cfbfd | 4528 | are rewritten. */ |
36f5ada1 ZD |
4529 | |
4530 | static struct iv_ca_delta * | |
4531 | iv_ca_delta_join (struct iv_ca_delta *l1, struct iv_ca_delta *l2) | |
4532 | { | |
4533 | struct iv_ca_delta *last; | |
4534 | ||
4535 | if (!l2) | |
4536 | return l1; | |
4537 | ||
4538 | if (!l1) | |
4539 | return l2; | |
4540 | ||
4541 | for (last = l1; last->next_change; last = last->next_change) | |
4542 | continue; | |
4543 | last->next_change = l2; | |
4544 | ||
4545 | return l1; | |
4546 | } | |
4547 | ||
b1b02be2 ZD |
4548 | /* Returns candidate by that USE is expressed in IVS. */ |
4549 | ||
4550 | static struct cost_pair * | |
4551 | iv_ca_cand_for_use (struct iv_ca *ivs, struct iv_use *use) | |
4552 | { | |
4553 | return ivs->cand_for_use[use->id]; | |
4554 | } | |
4555 | ||
36f5ada1 ZD |
4556 | /* Reverse the list of changes DELTA, forming the inverse to it. */ |
4557 | ||
4558 | static struct iv_ca_delta * | |
4559 | iv_ca_delta_reverse (struct iv_ca_delta *delta) | |
4560 | { | |
4561 | struct iv_ca_delta *act, *next, *prev = NULL; | |
4562 | struct cost_pair *tmp; | |
4563 | ||
4564 | for (act = delta; act; act = next) | |
4565 | { | |
4566 | next = act->next_change; | |
4567 | act->next_change = prev; | |
4568 | prev = act; | |
4569 | ||
4570 | tmp = act->old_cp; | |
4571 | act->old_cp = act->new_cp; | |
4572 | act->new_cp = tmp; | |
4573 | } | |
4574 | ||
4575 | return prev; | |
4576 | } | |
4577 | ||
b1b02be2 ZD |
4578 | /* Commit changes in DELTA to IVS. If FORWARD is false, the changes are |
4579 | reverted instead. */ | |
4580 | ||
4581 | static void | |
4582 | iv_ca_delta_commit (struct ivopts_data *data, struct iv_ca *ivs, | |
4583 | struct iv_ca_delta *delta, bool forward) | |
4584 | { | |
4585 | struct cost_pair *from, *to; | |
36f5ada1 | 4586 | struct iv_ca_delta *act; |
b1b02be2 | 4587 | |
36f5ada1 ZD |
4588 | if (!forward) |
4589 | delta = iv_ca_delta_reverse (delta); | |
b1b02be2 | 4590 | |
36f5ada1 ZD |
4591 | for (act = delta; act; act = act->next_change) |
4592 | { | |
4593 | from = act->old_cp; | |
4594 | to = act->new_cp; | |
4595 | gcc_assert (iv_ca_cand_for_use (ivs, act->use) == from); | |
4596 | iv_ca_set_cp (data, ivs, act->use, to); | |
8b11a64c | 4597 | } |
36f5ada1 ZD |
4598 | |
4599 | if (!forward) | |
4600 | iv_ca_delta_reverse (delta); | |
b1b02be2 | 4601 | } |
8b11a64c | 4602 | |
b1b02be2 | 4603 | /* Returns true if CAND is used in IVS. */ |
8b11a64c | 4604 | |
b1b02be2 ZD |
4605 | static bool |
4606 | iv_ca_cand_used_p (struct iv_ca *ivs, struct iv_cand *cand) | |
4607 | { | |
4608 | return ivs->n_cand_uses[cand->id] > 0; | |
4609 | } | |
8b11a64c | 4610 | |
36f5ada1 ZD |
4611 | /* Returns number of induction variable candidates in the set IVS. */ |
4612 | ||
4613 | static unsigned | |
4614 | iv_ca_n_cands (struct iv_ca *ivs) | |
4615 | { | |
4616 | return ivs->n_cands; | |
4617 | } | |
4618 | ||
b1b02be2 ZD |
4619 | /* Free the list of changes DELTA. */ |
4620 | ||
4621 | static void | |
4622 | iv_ca_delta_free (struct iv_ca_delta **delta) | |
4623 | { | |
4624 | struct iv_ca_delta *act, *next; | |
4625 | ||
4626 | for (act = *delta; act; act = next) | |
87c476a2 | 4627 | { |
b1b02be2 ZD |
4628 | next = act->next_change; |
4629 | free (act); | |
87c476a2 | 4630 | } |
8b11a64c | 4631 | |
b1b02be2 ZD |
4632 | *delta = NULL; |
4633 | } | |
4634 | ||
4635 | /* Allocates new iv candidates assignment. */ | |
4636 | ||
4637 | static struct iv_ca * | |
4638 | iv_ca_new (struct ivopts_data *data) | |
4639 | { | |
5ed6ace5 | 4640 | struct iv_ca *nw = XNEW (struct iv_ca); |
8b11a64c | 4641 | |
b1b02be2 ZD |
4642 | nw->upto = 0; |
4643 | nw->bad_uses = 0; | |
5ed6ace5 MD |
4644 | nw->cand_for_use = XCNEWVEC (struct cost_pair *, n_iv_uses (data)); |
4645 | nw->n_cand_uses = XCNEWVEC (unsigned, n_iv_cands (data)); | |
8bdbfff5 | 4646 | nw->cands = BITMAP_ALLOC (NULL); |
36f5ada1 | 4647 | nw->n_cands = 0; |
b1b02be2 ZD |
4648 | nw->n_regs = 0; |
4649 | nw->cand_use_cost = 0; | |
4650 | nw->cand_cost = 0; | |
5ed6ace5 | 4651 | nw->n_invariant_uses = XCNEWVEC (unsigned, data->max_inv_id + 1); |
b1b02be2 ZD |
4652 | nw->cost = 0; |
4653 | ||
4654 | return nw; | |
4655 | } | |
4656 | ||
4657 | /* Free memory occupied by the set IVS. */ | |
4658 | ||
4659 | static void | |
4660 | iv_ca_free (struct iv_ca **ivs) | |
4661 | { | |
4662 | free ((*ivs)->cand_for_use); | |
4663 | free ((*ivs)->n_cand_uses); | |
8bdbfff5 | 4664 | BITMAP_FREE ((*ivs)->cands); |
b1b02be2 ZD |
4665 | free ((*ivs)->n_invariant_uses); |
4666 | free (*ivs); | |
4667 | *ivs = NULL; | |
4668 | } | |
4669 | ||
4670 | /* Dumps IVS to FILE. */ | |
4671 | ||
4672 | static void | |
4673 | iv_ca_dump (struct ivopts_data *data, FILE *file, struct iv_ca *ivs) | |
4674 | { | |
4675 | const char *pref = " invariants "; | |
4676 | unsigned i; | |
4677 | ||
4678 | fprintf (file, " cost %d\n", iv_ca_cost (ivs)); | |
4679 | bitmap_print (file, ivs->cands, " candidates ","\n"); | |
4680 | ||
4681 | for (i = 1; i <= data->max_inv_id; i++) | |
4682 | if (ivs->n_invariant_uses[i]) | |
4683 | { | |
4684 | fprintf (file, "%s%d", pref, i); | |
4685 | pref = ", "; | |
4686 | } | |
4687 | fprintf (file, "\n"); | |
4688 | } | |
4689 | ||
4690 | /* Try changing candidate in IVS to CAND for each use. Return cost of the | |
36f5ada1 ZD |
4691 | new set, and store differences in DELTA. Number of induction variables |
4692 | in the new set is stored to N_IVS. */ | |
b1b02be2 ZD |
4693 | |
4694 | static unsigned | |
4695 | iv_ca_extend (struct ivopts_data *data, struct iv_ca *ivs, | |
36f5ada1 ZD |
4696 | struct iv_cand *cand, struct iv_ca_delta **delta, |
4697 | unsigned *n_ivs) | |
b1b02be2 ZD |
4698 | { |
4699 | unsigned i, cost; | |
4700 | struct iv_use *use; | |
4701 | struct cost_pair *old_cp, *new_cp; | |
4702 | ||
4703 | *delta = NULL; | |
4704 | for (i = 0; i < ivs->upto; i++) | |
4705 | { | |
4706 | use = iv_use (data, i); | |
4707 | old_cp = iv_ca_cand_for_use (ivs, use); | |
4708 | ||
4709 | if (old_cp | |
4710 | && old_cp->cand == cand) | |
4711 | continue; | |
4712 | ||
4713 | new_cp = get_use_iv_cost (data, use, cand); | |
4714 | if (!new_cp) | |
4715 | continue; | |
4716 | ||
4717 | if (!iv_ca_has_deps (ivs, new_cp)) | |
4718 | continue; | |
4719 | ||
4720 | if (!cheaper_cost_pair (new_cp, old_cp)) | |
4721 | continue; | |
4722 | ||
4723 | *delta = iv_ca_delta_add (use, old_cp, new_cp, *delta); | |
4724 | } | |
4725 | ||
4726 | iv_ca_delta_commit (data, ivs, *delta, true); | |
4727 | cost = iv_ca_cost (ivs); | |
36f5ada1 ZD |
4728 | if (n_ivs) |
4729 | *n_ivs = iv_ca_n_cands (ivs); | |
b1b02be2 | 4730 | iv_ca_delta_commit (data, ivs, *delta, false); |
8b11a64c ZD |
4731 | |
4732 | return cost; | |
4733 | } | |
4734 | ||
a0eca485 | 4735 | /* Try narrowing set IVS by removing CAND. Return the cost of |
b1b02be2 | 4736 | the new set and store the differences in DELTA. */ |
8b11a64c ZD |
4737 | |
4738 | static unsigned | |
b1b02be2 ZD |
4739 | iv_ca_narrow (struct ivopts_data *data, struct iv_ca *ivs, |
4740 | struct iv_cand *cand, struct iv_ca_delta **delta) | |
8b11a64c | 4741 | { |
b1b02be2 ZD |
4742 | unsigned i, ci; |
4743 | struct iv_use *use; | |
4744 | struct cost_pair *old_cp, *new_cp, *cp; | |
4745 | bitmap_iterator bi; | |
4746 | struct iv_cand *cnd; | |
4747 | unsigned cost; | |
4748 | ||
4749 | *delta = NULL; | |
4750 | for (i = 0; i < n_iv_uses (data); i++) | |
4751 | { | |
4752 | use = iv_use (data, i); | |
4753 | ||
4754 | old_cp = iv_ca_cand_for_use (ivs, use); | |
4755 | if (old_cp->cand != cand) | |
4756 | continue; | |
4757 | ||
4758 | new_cp = NULL; | |
4759 | ||
4760 | if (data->consider_all_candidates) | |
4761 | { | |
4762 | EXECUTE_IF_SET_IN_BITMAP (ivs->cands, 0, ci, bi) | |
4763 | { | |
4764 | if (ci == cand->id) | |
4765 | continue; | |
4766 | ||
4767 | cnd = iv_cand (data, ci); | |
4768 | ||
4769 | cp = get_use_iv_cost (data, use, cnd); | |
4770 | if (!cp) | |
4771 | continue; | |
4772 | if (!iv_ca_has_deps (ivs, cp)) | |
4773 | continue; | |
4774 | ||
4775 | if (!cheaper_cost_pair (cp, new_cp)) | |
4776 | continue; | |
4777 | ||
4778 | new_cp = cp; | |
4779 | } | |
4780 | } | |
4781 | else | |
4782 | { | |
4783 | EXECUTE_IF_AND_IN_BITMAP (use->related_cands, ivs->cands, 0, ci, bi) | |
4784 | { | |
4785 | if (ci == cand->id) | |
4786 | continue; | |
4787 | ||
4788 | cnd = iv_cand (data, ci); | |
4789 | ||
4790 | cp = get_use_iv_cost (data, use, cnd); | |
4791 | if (!cp) | |
4792 | continue; | |
4793 | if (!iv_ca_has_deps (ivs, cp)) | |
4794 | continue; | |
4795 | ||
4796 | if (!cheaper_cost_pair (cp, new_cp)) | |
4797 | continue; | |
4798 | ||
4799 | new_cp = cp; | |
4800 | } | |
4801 | } | |
4802 | ||
4803 | if (!new_cp) | |
4804 | { | |
4805 | iv_ca_delta_free (delta); | |
4806 | return INFTY; | |
4807 | } | |
4808 | ||
4809 | *delta = iv_ca_delta_add (use, old_cp, new_cp, *delta); | |
4810 | } | |
4811 | ||
4812 | iv_ca_delta_commit (data, ivs, *delta, true); | |
4813 | cost = iv_ca_cost (ivs); | |
4814 | iv_ca_delta_commit (data, ivs, *delta, false); | |
4815 | ||
4816 | return cost; | |
8b11a64c ZD |
4817 | } |
4818 | ||
36f5ada1 ZD |
4819 | /* Try optimizing the set of candidates IVS by removing candidates different |
4820 | from to EXCEPT_CAND from it. Return cost of the new set, and store | |
4821 | differences in DELTA. */ | |
4822 | ||
4823 | static unsigned | |
4824 | iv_ca_prune (struct ivopts_data *data, struct iv_ca *ivs, | |
4825 | struct iv_cand *except_cand, struct iv_ca_delta **delta) | |
4826 | { | |
4827 | bitmap_iterator bi; | |
4828 | struct iv_ca_delta *act_delta, *best_delta; | |
4829 | unsigned i, best_cost, acost; | |
4830 | struct iv_cand *cand; | |
4831 | ||
4832 | best_delta = NULL; | |
4833 | best_cost = iv_ca_cost (ivs); | |
4834 | ||
4835 | EXECUTE_IF_SET_IN_BITMAP (ivs->cands, 0, i, bi) | |
4836 | { | |
4837 | cand = iv_cand (data, i); | |
4838 | ||
4839 | if (cand == except_cand) | |
4840 | continue; | |
4841 | ||
4842 | acost = iv_ca_narrow (data, ivs, cand, &act_delta); | |
4843 | ||
4844 | if (acost < best_cost) | |
4845 | { | |
4846 | best_cost = acost; | |
4847 | iv_ca_delta_free (&best_delta); | |
4848 | best_delta = act_delta; | |
4849 | } | |
4850 | else | |
4851 | iv_ca_delta_free (&act_delta); | |
4852 | } | |
4853 | ||
4854 | if (!best_delta) | |
4855 | { | |
4856 | *delta = NULL; | |
4857 | return best_cost; | |
4858 | } | |
4859 | ||
4860 | /* Recurse to possibly remove other unnecessary ivs. */ | |
4861 | iv_ca_delta_commit (data, ivs, best_delta, true); | |
4862 | best_cost = iv_ca_prune (data, ivs, except_cand, delta); | |
4863 | iv_ca_delta_commit (data, ivs, best_delta, false); | |
4864 | *delta = iv_ca_delta_join (best_delta, *delta); | |
4865 | return best_cost; | |
4866 | } | |
4867 | ||
b1b02be2 | 4868 | /* Tries to extend the sets IVS in the best possible way in order |
8b11a64c ZD |
4869 | to express the USE. */ |
4870 | ||
4871 | static bool | |
b1b02be2 | 4872 | try_add_cand_for (struct ivopts_data *data, struct iv_ca *ivs, |
8b11a64c ZD |
4873 | struct iv_use *use) |
4874 | { | |
b1b02be2 | 4875 | unsigned best_cost, act_cost; |
8b11a64c | 4876 | unsigned i; |
38b0dcb8 ZD |
4877 | bitmap_iterator bi; |
4878 | struct iv_cand *cand; | |
b1b02be2 ZD |
4879 | struct iv_ca_delta *best_delta = NULL, *act_delta; |
4880 | struct cost_pair *cp; | |
4881 | ||
4882 | iv_ca_add_use (data, ivs, use); | |
4883 | best_cost = iv_ca_cost (ivs); | |
8b11a64c | 4884 | |
b1b02be2 ZD |
4885 | cp = iv_ca_cand_for_use (ivs, use); |
4886 | if (cp) | |
4887 | { | |
4888 | best_delta = iv_ca_delta_add (use, NULL, cp, NULL); | |
4889 | iv_ca_set_no_cp (data, ivs, use); | |
4890 | } | |
8b11a64c | 4891 | |
38b0dcb8 ZD |
4892 | /* First try important candidates. Only if it fails, try the specific ones. |
4893 | Rationale -- in loops with many variables the best choice often is to use | |
4894 | just one generic biv. If we added here many ivs specific to the uses, | |
4895 | the optimization algorithm later would be likely to get stuck in a local | |
4896 | minimum, thus causing us to create too many ivs. The approach from | |
1c170b5e | 4897 | few ivs to more seems more likely to be successful -- starting from few |
38b0dcb8 ZD |
4898 | ivs, replacing an expensive use by a specific iv should always be a |
4899 | win. */ | |
4900 | EXECUTE_IF_SET_IN_BITMAP (data->important_candidates, 0, i, bi) | |
8b11a64c | 4901 | { |
38b0dcb8 ZD |
4902 | cand = iv_cand (data, i); |
4903 | ||
b1b02be2 | 4904 | if (iv_ca_cand_used_p (ivs, cand)) |
8b11a64c ZD |
4905 | continue; |
4906 | ||
b1b02be2 ZD |
4907 | cp = get_use_iv_cost (data, use, cand); |
4908 | if (!cp) | |
4909 | continue; | |
4910 | ||
4911 | iv_ca_set_cp (data, ivs, use, cp); | |
36f5ada1 | 4912 | act_cost = iv_ca_extend (data, ivs, cand, &act_delta, NULL); |
b1b02be2 ZD |
4913 | iv_ca_set_no_cp (data, ivs, use); |
4914 | act_delta = iv_ca_delta_add (use, NULL, cp, act_delta); | |
8b11a64c ZD |
4915 | |
4916 | if (act_cost < best_cost) | |
4917 | { | |
4918 | best_cost = act_cost; | |
b1b02be2 ZD |
4919 | |
4920 | iv_ca_delta_free (&best_delta); | |
4921 | best_delta = act_delta; | |
8b11a64c | 4922 | } |
b1b02be2 ZD |
4923 | else |
4924 | iv_ca_delta_free (&act_delta); | |
8b11a64c ZD |
4925 | } |
4926 | ||
38b0dcb8 ZD |
4927 | if (best_cost == INFTY) |
4928 | { | |
4929 | for (i = 0; i < use->n_map_members; i++) | |
4930 | { | |
4931 | cp = use->cost_map + i; | |
b1b02be2 ZD |
4932 | cand = cp->cand; |
4933 | if (!cand) | |
38b0dcb8 ZD |
4934 | continue; |
4935 | ||
4936 | /* Already tried this. */ | |
b1b02be2 ZD |
4937 | if (cand->important) |
4938 | continue; | |
4939 | ||
4940 | if (iv_ca_cand_used_p (ivs, cand)) | |
38b0dcb8 ZD |
4941 | continue; |
4942 | ||
b1b02be2 ZD |
4943 | act_delta = NULL; |
4944 | iv_ca_set_cp (data, ivs, use, cp); | |
36f5ada1 | 4945 | act_cost = iv_ca_extend (data, ivs, cand, &act_delta, NULL); |
b1b02be2 ZD |
4946 | iv_ca_set_no_cp (data, ivs, use); |
4947 | act_delta = iv_ca_delta_add (use, iv_ca_cand_for_use (ivs, use), | |
4948 | cp, act_delta); | |
38b0dcb8 ZD |
4949 | |
4950 | if (act_cost < best_cost) | |
4951 | { | |
4952 | best_cost = act_cost; | |
b1b02be2 ZD |
4953 | |
4954 | if (best_delta) | |
4955 | iv_ca_delta_free (&best_delta); | |
4956 | best_delta = act_delta; | |
38b0dcb8 | 4957 | } |
b1b02be2 ZD |
4958 | else |
4959 | iv_ca_delta_free (&act_delta); | |
38b0dcb8 ZD |
4960 | } |
4961 | } | |
4962 | ||
b1b02be2 ZD |
4963 | iv_ca_delta_commit (data, ivs, best_delta, true); |
4964 | iv_ca_delta_free (&best_delta); | |
8b11a64c ZD |
4965 | |
4966 | return (best_cost != INFTY); | |
4967 | } | |
4968 | ||
b1b02be2 | 4969 | /* Finds an initial assignment of candidates to uses. */ |
8b11a64c | 4970 | |
b1b02be2 ZD |
4971 | static struct iv_ca * |
4972 | get_initial_solution (struct ivopts_data *data) | |
8b11a64c | 4973 | { |
b1b02be2 | 4974 | struct iv_ca *ivs = iv_ca_new (data); |
8b11a64c ZD |
4975 | unsigned i; |
4976 | ||
4977 | for (i = 0; i < n_iv_uses (data); i++) | |
b1b02be2 ZD |
4978 | if (!try_add_cand_for (data, ivs, iv_use (data, i))) |
4979 | { | |
4980 | iv_ca_free (&ivs); | |
4981 | return NULL; | |
4982 | } | |
8b11a64c | 4983 | |
b1b02be2 | 4984 | return ivs; |
8b11a64c ZD |
4985 | } |
4986 | ||
b1b02be2 | 4987 | /* Tries to improve set of induction variables IVS. */ |
8b11a64c ZD |
4988 | |
4989 | static bool | |
b1b02be2 | 4990 | try_improve_iv_set (struct ivopts_data *data, struct iv_ca *ivs) |
8b11a64c | 4991 | { |
36f5ada1 ZD |
4992 | unsigned i, acost, best_cost = iv_ca_cost (ivs), n_ivs; |
4993 | struct iv_ca_delta *best_delta = NULL, *act_delta, *tmp_delta; | |
b1b02be2 | 4994 | struct iv_cand *cand; |
8b11a64c | 4995 | |
36f5ada1 | 4996 | /* Try extending the set of induction variables by one. */ |
8b11a64c ZD |
4997 | for (i = 0; i < n_iv_cands (data); i++) |
4998 | { | |
b1b02be2 ZD |
4999 | cand = iv_cand (data, i); |
5000 | ||
5001 | if (iv_ca_cand_used_p (ivs, cand)) | |
36f5ada1 ZD |
5002 | continue; |
5003 | ||
5004 | acost = iv_ca_extend (data, ivs, cand, &act_delta, &n_ivs); | |
5005 | if (!act_delta) | |
5006 | continue; | |
5007 | ||
5008 | /* If we successfully added the candidate and the set is small enough, | |
5009 | try optimizing it by removing other candidates. */ | |
5010 | if (n_ivs <= ALWAYS_PRUNE_CAND_SET_BOUND) | |
5011 | { | |
5012 | iv_ca_delta_commit (data, ivs, act_delta, true); | |
5013 | acost = iv_ca_prune (data, ivs, cand, &tmp_delta); | |
5014 | iv_ca_delta_commit (data, ivs, act_delta, false); | |
5015 | act_delta = iv_ca_delta_join (act_delta, tmp_delta); | |
5016 | } | |
8b11a64c | 5017 | |
b1b02be2 | 5018 | if (acost < best_cost) |
8b11a64c | 5019 | { |
b1b02be2 | 5020 | best_cost = acost; |
36f5ada1 | 5021 | iv_ca_delta_free (&best_delta); |
b1b02be2 | 5022 | best_delta = act_delta; |
8b11a64c | 5023 | } |
8b11a64c | 5024 | else |
b1b02be2 | 5025 | iv_ca_delta_free (&act_delta); |
8b11a64c ZD |
5026 | } |
5027 | ||
b1b02be2 | 5028 | if (!best_delta) |
36f5ada1 ZD |
5029 | { |
5030 | /* Try removing the candidates from the set instead. */ | |
5031 | best_cost = iv_ca_prune (data, ivs, NULL, &best_delta); | |
5032 | ||
5033 | /* Nothing more we can do. */ | |
5034 | if (!best_delta) | |
5035 | return false; | |
5036 | } | |
8b11a64c | 5037 | |
b1b02be2 | 5038 | iv_ca_delta_commit (data, ivs, best_delta, true); |
36f5ada1 | 5039 | gcc_assert (best_cost == iv_ca_cost (ivs)); |
b1b02be2 | 5040 | iv_ca_delta_free (&best_delta); |
8b11a64c ZD |
5041 | return true; |
5042 | } | |
5043 | ||
5044 | /* Attempts to find the optimal set of induction variables. We do simple | |
5045 | greedy heuristic -- we try to replace at most one candidate in the selected | |
5046 | solution and remove the unused ivs while this improves the cost. */ | |
5047 | ||
b1b02be2 | 5048 | static struct iv_ca * |
8b11a64c ZD |
5049 | find_optimal_iv_set (struct ivopts_data *data) |
5050 | { | |
b1b02be2 ZD |
5051 | unsigned i; |
5052 | struct iv_ca *set; | |
8b11a64c ZD |
5053 | struct iv_use *use; |
5054 | ||
b1b02be2 ZD |
5055 | /* Get the initial solution. */ |
5056 | set = get_initial_solution (data); | |
5057 | if (!set) | |
8b11a64c ZD |
5058 | { |
5059 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
5060 | fprintf (dump_file, "Unable to substitute for ivs, failed.\n"); | |
8b11a64c ZD |
5061 | return NULL; |
5062 | } | |
5063 | ||
5064 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
5065 | { | |
b1b02be2 ZD |
5066 | fprintf (dump_file, "Initial set of candidates:\n"); |
5067 | iv_ca_dump (data, dump_file, set); | |
8b11a64c ZD |
5068 | } |
5069 | ||
b1b02be2 | 5070 | while (try_improve_iv_set (data, set)) |
8b11a64c ZD |
5071 | { |
5072 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
5073 | { | |
b1b02be2 ZD |
5074 | fprintf (dump_file, "Improved to:\n"); |
5075 | iv_ca_dump (data, dump_file, set); | |
8b11a64c ZD |
5076 | } |
5077 | } | |
5078 | ||
5079 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
b1b02be2 | 5080 | fprintf (dump_file, "Final cost %d\n\n", iv_ca_cost (set)); |
8b11a64c ZD |
5081 | |
5082 | for (i = 0; i < n_iv_uses (data); i++) | |
5083 | { | |
5084 | use = iv_use (data, i); | |
b1b02be2 | 5085 | use->selected = iv_ca_cand_for_use (set, use)->cand; |
8b11a64c ZD |
5086 | } |
5087 | ||
8b11a64c ZD |
5088 | return set; |
5089 | } | |
5090 | ||
5091 | /* Creates a new induction variable corresponding to CAND. */ | |
5092 | ||
5093 | static void | |
5094 | create_new_iv (struct ivopts_data *data, struct iv_cand *cand) | |
5095 | { | |
5096 | block_stmt_iterator incr_pos; | |
5097 | tree base; | |
5098 | bool after = false; | |
5099 | ||
5100 | if (!cand->iv) | |
5101 | return; | |
5102 | ||
5103 | switch (cand->pos) | |
5104 | { | |
5105 | case IP_NORMAL: | |
5106 | incr_pos = bsi_last (ip_normal_pos (data->current_loop)); | |
5107 | break; | |
5108 | ||
5109 | case IP_END: | |
5110 | incr_pos = bsi_last (ip_end_pos (data->current_loop)); | |
5111 | after = true; | |
5112 | break; | |
5113 | ||
5114 | case IP_ORIGINAL: | |
5115 | /* Mark that the iv is preserved. */ | |
5116 | name_info (data, cand->var_before)->preserve_biv = true; | |
5117 | name_info (data, cand->var_after)->preserve_biv = true; | |
5118 | ||
5119 | /* Rewrite the increment so that it uses var_before directly. */ | |
5120 | find_interesting_uses_op (data, cand->var_after)->selected = cand; | |
5121 | ||
5122 | return; | |
5123 | } | |
5124 | ||
5125 | gimple_add_tmp_var (cand->var_before); | |
5126 | add_referenced_tmp_var (cand->var_before); | |
5127 | ||
5128 | base = unshare_expr (cand->iv->base); | |
5129 | ||
9be872b7 ZD |
5130 | create_iv (base, unshare_expr (cand->iv->step), |
5131 | cand->var_before, data->current_loop, | |
8b11a64c ZD |
5132 | &incr_pos, after, &cand->var_before, &cand->var_after); |
5133 | } | |
5134 | ||
5135 | /* Creates new induction variables described in SET. */ | |
5136 | ||
5137 | static void | |
b1b02be2 | 5138 | create_new_ivs (struct ivopts_data *data, struct iv_ca *set) |
8b11a64c ZD |
5139 | { |
5140 | unsigned i; | |
5141 | struct iv_cand *cand; | |
87c476a2 | 5142 | bitmap_iterator bi; |
8b11a64c | 5143 | |
b1b02be2 | 5144 | EXECUTE_IF_SET_IN_BITMAP (set->cands, 0, i, bi) |
8b11a64c ZD |
5145 | { |
5146 | cand = iv_cand (data, i); | |
5147 | create_new_iv (data, cand); | |
87c476a2 | 5148 | } |
8b11a64c ZD |
5149 | } |
5150 | ||
5151 | /* Removes statement STMT (real or a phi node). If INCLUDING_DEFINED_NAME | |
5152 | is true, remove also the ssa name defined by the statement. */ | |
5153 | ||
5154 | static void | |
5155 | remove_statement (tree stmt, bool including_defined_name) | |
5156 | { | |
5157 | if (TREE_CODE (stmt) == PHI_NODE) | |
5158 | { | |
5159 | if (!including_defined_name) | |
5160 | { | |
5161 | /* Prevent the ssa name defined by the statement from being removed. */ | |
5162 | SET_PHI_RESULT (stmt, NULL); | |
5163 | } | |
d19e3ef6 | 5164 | remove_phi_node (stmt, NULL_TREE); |
8b11a64c ZD |
5165 | } |
5166 | else | |
5167 | { | |
1a1804c2 | 5168 | block_stmt_iterator bsi = bsi_for_stmt (stmt); |
8b11a64c | 5169 | |
736432ee | 5170 | bsi_remove (&bsi, true); |
8b11a64c ZD |
5171 | } |
5172 | } | |
5173 | ||
5174 | /* Rewrites USE (definition of iv used in a nonlinear expression) | |
5175 | using candidate CAND. */ | |
5176 | ||
5177 | static void | |
5178 | rewrite_use_nonlinear_expr (struct ivopts_data *data, | |
5179 | struct iv_use *use, struct iv_cand *cand) | |
5180 | { | |
3520b745 | 5181 | tree comp; |
8b11a64c ZD |
5182 | tree op, stmts, tgt, ass; |
5183 | block_stmt_iterator bsi, pbsi; | |
3520b745 ZD |
5184 | |
5185 | /* An important special case -- if we are asked to express value of | |
5186 | the original iv by itself, just exit; there is no need to | |
5187 | introduce a new computation (that might also need casting the | |
5188 | variable to unsigned and back). */ | |
5189 | if (cand->pos == IP_ORIGINAL | |
7b9d4f70 | 5190 | && cand->incremented_at == use->stmt) |
3520b745 | 5191 | { |
7b9d4f70 ZD |
5192 | tree step, ctype, utype; |
5193 | enum tree_code incr_code = PLUS_EXPR; | |
5194 | ||
5195 | gcc_assert (TREE_CODE (use->stmt) == MODIFY_EXPR); | |
5196 | gcc_assert (TREE_OPERAND (use->stmt, 0) == cand->var_after); | |
5197 | ||
5198 | step = cand->iv->step; | |
5199 | ctype = TREE_TYPE (step); | |
5200 | utype = TREE_TYPE (cand->var_after); | |
5201 | if (TREE_CODE (step) == NEGATE_EXPR) | |
5202 | { | |
5203 | incr_code = MINUS_EXPR; | |
5204 | step = TREE_OPERAND (step, 0); | |
5205 | } | |
5206 | ||
5207 | /* Check whether we may leave the computation unchanged. | |
5208 | This is the case only if it does not rely on other | |
5209 | computations in the loop -- otherwise, the computation | |
5210 | we rely upon may be removed in remove_unused_ivs, | |
5211 | thus leading to ICE. */ | |
3520b745 | 5212 | op = TREE_OPERAND (use->stmt, 1); |
7b9d4f70 ZD |
5213 | if (TREE_CODE (op) == PLUS_EXPR |
5214 | || TREE_CODE (op) == MINUS_EXPR) | |
5215 | { | |
5216 | if (TREE_OPERAND (op, 0) == cand->var_before) | |
5217 | op = TREE_OPERAND (op, 1); | |
5218 | else if (TREE_CODE (op) == PLUS_EXPR | |
5219 | && TREE_OPERAND (op, 1) == cand->var_before) | |
5220 | op = TREE_OPERAND (op, 0); | |
5221 | else | |
5222 | op = NULL_TREE; | |
5223 | } | |
5224 | else | |
5225 | op = NULL_TREE; | |
3520b745 | 5226 | |
7b9d4f70 ZD |
5227 | if (op |
5228 | && (TREE_CODE (op) == INTEGER_CST | |
5229 | || operand_equal_p (op, step, 0))) | |
3520b745 | 5230 | return; |
7b9d4f70 ZD |
5231 | |
5232 | /* Otherwise, add the necessary computations to express | |
5233 | the iv. */ | |
5234 | op = fold_convert (ctype, cand->var_before); | |
5235 | comp = fold_convert (utype, | |
5236 | build2 (incr_code, ctype, op, | |
5237 | unshare_expr (step))); | |
3520b745 | 5238 | } |
7b9d4f70 ZD |
5239 | else |
5240 | comp = get_computation (data->current_loop, use, cand); | |
3520b745 | 5241 | |
1e128c5f | 5242 | switch (TREE_CODE (use->stmt)) |
8b11a64c | 5243 | { |
1e128c5f | 5244 | case PHI_NODE: |
8b11a64c ZD |
5245 | tgt = PHI_RESULT (use->stmt); |
5246 | ||
5247 | /* If we should keep the biv, do not replace it. */ | |
5248 | if (name_info (data, tgt)->preserve_biv) | |
5249 | return; | |
5250 | ||
5251 | pbsi = bsi = bsi_start (bb_for_stmt (use->stmt)); | |
5252 | while (!bsi_end_p (pbsi) | |
5253 | && TREE_CODE (bsi_stmt (pbsi)) == LABEL_EXPR) | |
5254 | { | |
5255 | bsi = pbsi; | |
5256 | bsi_next (&pbsi); | |
5257 | } | |
1e128c5f GB |
5258 | break; |
5259 | ||
5260 | case MODIFY_EXPR: | |
8b11a64c | 5261 | tgt = TREE_OPERAND (use->stmt, 0); |
1a1804c2 | 5262 | bsi = bsi_for_stmt (use->stmt); |
1e128c5f GB |
5263 | break; |
5264 | ||
5265 | default: | |
5266 | gcc_unreachable (); | |
8b11a64c | 5267 | } |
8b11a64c ZD |
5268 | |
5269 | op = force_gimple_operand (comp, &stmts, false, SSA_NAME_VAR (tgt)); | |
5270 | ||
5271 | if (TREE_CODE (use->stmt) == PHI_NODE) | |
5272 | { | |
5273 | if (stmts) | |
5274 | bsi_insert_after (&bsi, stmts, BSI_CONTINUE_LINKING); | |
5275 | ass = build2 (MODIFY_EXPR, TREE_TYPE (tgt), tgt, op); | |
5276 | bsi_insert_after (&bsi, ass, BSI_NEW_STMT); | |
5277 | remove_statement (use->stmt, false); | |
5278 | SSA_NAME_DEF_STMT (tgt) = ass; | |
5279 | } | |
5280 | else | |
5281 | { | |
5282 | if (stmts) | |
5283 | bsi_insert_before (&bsi, stmts, BSI_SAME_STMT); | |
5284 | TREE_OPERAND (use->stmt, 1) = op; | |
5285 | } | |
5286 | } | |
5287 | ||
5288 | /* Replaces ssa name in index IDX by its basic variable. Callback for | |
5289 | for_each_index. */ | |
5290 | ||
5291 | static bool | |
be35cf60 | 5292 | idx_remove_ssa_names (tree base, tree *idx, |
8b11a64c ZD |
5293 | void *data ATTRIBUTE_UNUSED) |
5294 | { | |
be35cf60 ZD |
5295 | tree *op; |
5296 | ||
8b11a64c ZD |
5297 | if (TREE_CODE (*idx) == SSA_NAME) |
5298 | *idx = SSA_NAME_VAR (*idx); | |
be35cf60 ZD |
5299 | |
5300 | if (TREE_CODE (base) == ARRAY_REF) | |
5301 | { | |
5302 | op = &TREE_OPERAND (base, 2); | |
5303 | if (*op | |
5304 | && TREE_CODE (*op) == SSA_NAME) | |
5305 | *op = SSA_NAME_VAR (*op); | |
5306 | op = &TREE_OPERAND (base, 3); | |
5307 | if (*op | |
5308 | && TREE_CODE (*op) == SSA_NAME) | |
5309 | *op = SSA_NAME_VAR (*op); | |
5310 | } | |
5311 | ||
8b11a64c ZD |
5312 | return true; |
5313 | } | |
5314 | ||
5315 | /* Unshares REF and replaces ssa names inside it by their basic variables. */ | |
5316 | ||
5317 | static tree | |
5318 | unshare_and_remove_ssa_names (tree ref) | |
5319 | { | |
5320 | ref = unshare_expr (ref); | |
5321 | for_each_index (&ref, idx_remove_ssa_names, NULL); | |
5322 | ||
5323 | return ref; | |
5324 | } | |
5325 | ||
ac182688 ZD |
5326 | /* Extract the alias analysis info for the memory reference REF. There are |
5327 | several ways how this information may be stored and what precisely is | |
5328 | its semantics depending on the type of the reference, but there always is | |
5329 | somewhere hidden one _DECL node that is used to determine the set of | |
5330 | virtual operands for the reference. The code below deciphers this jungle | |
5331 | and extracts this single useful piece of information. */ | |
8b11a64c | 5332 | |
ac182688 | 5333 | static tree |
9be7ee44 | 5334 | get_ref_tag (tree ref, tree orig) |
8b11a64c | 5335 | { |
ac182688 | 5336 | tree var = get_base_address (ref); |
9be7ee44 ZD |
5337 | tree aref = NULL_TREE, tag, sv; |
5338 | HOST_WIDE_INT offset, size, maxsize; | |
5339 | ||
5340 | for (sv = orig; handled_component_p (sv); sv = TREE_OPERAND (sv, 0)) | |
5341 | { | |
5342 | aref = get_ref_base_and_extent (sv, &offset, &size, &maxsize); | |
5343 | if (ref) | |
5344 | break; | |
5345 | } | |
5346 | ||
5347 | if (aref && SSA_VAR_P (aref) && get_subvars_for_var (aref)) | |
5348 | return unshare_expr (sv); | |
7ccf35ed | 5349 | |
ac182688 ZD |
5350 | if (!var) |
5351 | return NULL_TREE; | |
be35cf60 | 5352 | |
be35cf60 | 5353 | if (TREE_CODE (var) == INDIRECT_REF) |
8b11a64c | 5354 | { |
18cd8a03 DN |
5355 | /* If the base is a dereference of a pointer, first check its name memory |
5356 | tag. If it does not have one, use its symbol memory tag. */ | |
2360a4c1 ZD |
5357 | var = TREE_OPERAND (var, 0); |
5358 | if (TREE_CODE (var) != SSA_NAME) | |
5359 | return NULL_TREE; | |
5360 | ||
ac182688 ZD |
5361 | if (SSA_NAME_PTR_INFO (var)) |
5362 | { | |
5363 | tag = SSA_NAME_PTR_INFO (var)->name_mem_tag; | |
5364 | if (tag) | |
5365 | return tag; | |
5366 | } | |
5367 | ||
8b11a64c | 5368 | var = SSA_NAME_VAR (var); |
18cd8a03 | 5369 | tag = var_ann (var)->symbol_mem_tag; |
2360a4c1 ZD |
5370 | gcc_assert (tag != NULL_TREE); |
5371 | return tag; | |
8b11a64c | 5372 | } |
2360a4c1 ZD |
5373 | else |
5374 | { | |
5375 | if (!DECL_P (var)) | |
5376 | return NULL_TREE; | |
5377 | ||
18cd8a03 | 5378 | tag = var_ann (var)->symbol_mem_tag; |
0bca51f0 | 5379 | if (tag) |
ac182688 | 5380 | return tag; |
8b11a64c | 5381 | |
ac182688 ZD |
5382 | return var; |
5383 | } | |
ac182688 | 5384 | } |
7ccf35ed | 5385 | |
ac182688 | 5386 | /* Copies the reference information from OLD_REF to NEW_REF. */ |
0bca51f0 | 5387 | |
ac182688 ZD |
5388 | static void |
5389 | copy_ref_info (tree new_ref, tree old_ref) | |
5390 | { | |
5391 | if (TREE_CODE (old_ref) == TARGET_MEM_REF) | |
5392 | copy_mem_ref_info (new_ref, old_ref); | |
5393 | else | |
5394 | { | |
ac182688 | 5395 | TMR_ORIGINAL (new_ref) = unshare_and_remove_ssa_names (old_ref); |
9be7ee44 | 5396 | TMR_TAG (new_ref) = get_ref_tag (old_ref, TMR_ORIGINAL (new_ref)); |
ac182688 | 5397 | } |
8b11a64c ZD |
5398 | } |
5399 | ||
5400 | /* Rewrites USE (address that is an iv) using candidate CAND. */ | |
5401 | ||
5402 | static void | |
5403 | rewrite_use_address (struct ivopts_data *data, | |
5404 | struct iv_use *use, struct iv_cand *cand) | |
5405 | { | |
ac182688 | 5406 | struct affine_tree_combination aff; |
1a1804c2 | 5407 | block_stmt_iterator bsi = bsi_for_stmt (use->stmt); |
ac182688 | 5408 | tree ref; |
8b11a64c | 5409 | |
ac182688 ZD |
5410 | get_computation_aff (data->current_loop, use, cand, use->stmt, &aff); |
5411 | unshare_aff_combination (&aff); | |
8b11a64c | 5412 | |
ac182688 ZD |
5413 | ref = create_mem_ref (&bsi, TREE_TYPE (*use->op_p), &aff); |
5414 | copy_ref_info (ref, *use->op_p); | |
5415 | *use->op_p = ref; | |
8b11a64c ZD |
5416 | } |
5417 | ||
5418 | /* Rewrites USE (the condition such that one of the arguments is an iv) using | |
5419 | candidate CAND. */ | |
5420 | ||
5421 | static void | |
5422 | rewrite_use_compare (struct ivopts_data *data, | |
5423 | struct iv_use *use, struct iv_cand *cand) | |
5424 | { | |
5425 | tree comp; | |
5426 | tree *op_p, cond, op, stmts, bound; | |
1a1804c2 | 5427 | block_stmt_iterator bsi = bsi_for_stmt (use->stmt); |
8b11a64c | 5428 | enum tree_code compare; |
f5f12961 | 5429 | struct cost_pair *cp = get_use_iv_cost (data, use, cand); |
8b11a64c | 5430 | |
f5f12961 ZD |
5431 | bound = cp->value; |
5432 | if (bound) | |
8b11a64c | 5433 | { |
9e7376e5 ZD |
5434 | tree var = var_at_stmt (data->current_loop, cand, use->stmt); |
5435 | tree var_type = TREE_TYPE (var); | |
5436 | ||
f5f12961 | 5437 | compare = iv_elimination_compare (data, use); |
9e7376e5 | 5438 | bound = fold_convert (var_type, bound); |
8b11a64c ZD |
5439 | op = force_gimple_operand (unshare_expr (bound), &stmts, |
5440 | true, NULL_TREE); | |
5441 | ||
5442 | if (stmts) | |
5443 | bsi_insert_before (&bsi, stmts, BSI_SAME_STMT); | |
5444 | ||
9e7376e5 | 5445 | *use->op_p = build2 (compare, boolean_type_node, var, op); |
f430bae8 | 5446 | update_stmt (use->stmt); |
8b11a64c ZD |
5447 | return; |
5448 | } | |
5449 | ||
5450 | /* The induction variable elimination failed; just express the original | |
5451 | giv. */ | |
ac182688 | 5452 | comp = get_computation (data->current_loop, use, cand); |
8b11a64c ZD |
5453 | |
5454 | cond = *use->op_p; | |
5455 | op_p = &TREE_OPERAND (cond, 0); | |
5456 | if (TREE_CODE (*op_p) != SSA_NAME | |
5457 | || zero_p (get_iv (data, *op_p)->step)) | |
5458 | op_p = &TREE_OPERAND (cond, 1); | |
5459 | ||
5460 | op = force_gimple_operand (comp, &stmts, true, SSA_NAME_VAR (*op_p)); | |
5461 | if (stmts) | |
5462 | bsi_insert_before (&bsi, stmts, BSI_SAME_STMT); | |
5463 | ||
5464 | *op_p = op; | |
5465 | } | |
5466 | ||
5467 | /* Ensure that operand *OP_P may be used at the end of EXIT without | |
5468 | violating loop closed ssa form. */ | |
5469 | ||
5470 | static void | |
5471 | protect_loop_closed_ssa_form_use (edge exit, use_operand_p op_p) | |
5472 | { | |
5473 | basic_block def_bb; | |
5474 | struct loop *def_loop; | |
5475 | tree phi, use; | |
5476 | ||
5477 | use = USE_FROM_PTR (op_p); | |
5478 | if (TREE_CODE (use) != SSA_NAME) | |
5479 | return; | |
5480 | ||
5481 | def_bb = bb_for_stmt (SSA_NAME_DEF_STMT (use)); | |
5482 | if (!def_bb) | |
5483 | return; | |
5484 | ||
5485 | def_loop = def_bb->loop_father; | |
5486 | if (flow_bb_inside_loop_p (def_loop, exit->dest)) | |
5487 | return; | |
5488 | ||
5489 | /* Try finding a phi node that copies the value out of the loop. */ | |
bb29d951 | 5490 | for (phi = phi_nodes (exit->dest); phi; phi = PHI_CHAIN (phi)) |
8b11a64c ZD |
5491 | if (PHI_ARG_DEF_FROM_EDGE (phi, exit) == use) |
5492 | break; | |
5493 | ||
5494 | if (!phi) | |
5495 | { | |
5496 | /* Create such a phi node. */ | |
5497 | tree new_name = duplicate_ssa_name (use, NULL); | |
5498 | ||
5499 | phi = create_phi_node (new_name, exit->dest); | |
5500 | SSA_NAME_DEF_STMT (new_name) = phi; | |
d2e398df | 5501 | add_phi_arg (phi, use, exit); |
8b11a64c ZD |
5502 | } |
5503 | ||
5504 | SET_USE (op_p, PHI_RESULT (phi)); | |
5505 | } | |
5506 | ||
5507 | /* Ensure that operands of STMT may be used at the end of EXIT without | |
5508 | violating loop closed ssa form. */ | |
5509 | ||
5510 | static void | |
5511 | protect_loop_closed_ssa_form (edge exit, tree stmt) | |
5512 | { | |
f47c96aa AM |
5513 | ssa_op_iter iter; |
5514 | use_operand_p use_p; | |
8b11a64c | 5515 | |
f47c96aa AM |
5516 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_ALL_USES) |
5517 | protect_loop_closed_ssa_form_use (exit, use_p); | |
8b11a64c ZD |
5518 | } |
5519 | ||
5520 | /* STMTS compute a value of a phi argument OP on EXIT of a loop. Arrange things | |
5521 | so that they are emitted on the correct place, and so that the loop closed | |
5522 | ssa form is preserved. */ | |
5523 | ||
3ac01fde | 5524 | void |
8b11a64c ZD |
5525 | compute_phi_arg_on_exit (edge exit, tree stmts, tree op) |
5526 | { | |
5527 | tree_stmt_iterator tsi; | |
5528 | block_stmt_iterator bsi; | |
5529 | tree phi, stmt, def, next; | |
5530 | ||
c5cbcccf | 5531 | if (!single_pred_p (exit->dest)) |
8b11a64c ZD |
5532 | split_loop_exit_edge (exit); |
5533 | ||
f430bae8 AM |
5534 | /* Ensure there is label in exit->dest, so that we can |
5535 | insert after it. */ | |
5536 | tree_block_label (exit->dest); | |
5537 | bsi = bsi_after_labels (exit->dest); | |
5538 | ||
8b11a64c ZD |
5539 | if (TREE_CODE (stmts) == STATEMENT_LIST) |
5540 | { | |
5541 | for (tsi = tsi_start (stmts); !tsi_end_p (tsi); tsi_next (&tsi)) | |
f430bae8 | 5542 | { |
35771d34 PB |
5543 | tree stmt = tsi_stmt (tsi); |
5544 | bsi_insert_before (&bsi, stmt, BSI_SAME_STMT); | |
5545 | protect_loop_closed_ssa_form (exit, stmt); | |
f430bae8 | 5546 | } |
8b11a64c ZD |
5547 | } |
5548 | else | |
f430bae8 | 5549 | { |
35771d34 PB |
5550 | bsi_insert_before (&bsi, stmts, BSI_SAME_STMT); |
5551 | protect_loop_closed_ssa_form (exit, stmts); | |
f430bae8 | 5552 | } |
8b11a64c ZD |
5553 | |
5554 | if (!op) | |
5555 | return; | |
5556 | ||
5557 | for (phi = phi_nodes (exit->dest); phi; phi = next) | |
5558 | { | |
eaf0dc02 | 5559 | next = PHI_CHAIN (phi); |
8b11a64c ZD |
5560 | |
5561 | if (PHI_ARG_DEF_FROM_EDGE (phi, exit) == op) | |
5562 | { | |
5563 | def = PHI_RESULT (phi); | |
5564 | remove_statement (phi, false); | |
5565 | stmt = build2 (MODIFY_EXPR, TREE_TYPE (op), | |
5566 | def, op); | |
5567 | SSA_NAME_DEF_STMT (def) = stmt; | |
35771d34 | 5568 | bsi_insert_before (&bsi, stmt, BSI_SAME_STMT); |
8b11a64c ZD |
5569 | } |
5570 | } | |
5571 | } | |
5572 | ||
8b11a64c ZD |
5573 | /* Rewrites USE using candidate CAND. */ |
5574 | ||
5575 | static void | |
5576 | rewrite_use (struct ivopts_data *data, | |
5577 | struct iv_use *use, struct iv_cand *cand) | |
5578 | { | |
5579 | switch (use->type) | |
5580 | { | |
5581 | case USE_NONLINEAR_EXPR: | |
5582 | rewrite_use_nonlinear_expr (data, use, cand); | |
5583 | break; | |
5584 | ||
8b11a64c ZD |
5585 | case USE_ADDRESS: |
5586 | rewrite_use_address (data, use, cand); | |
5587 | break; | |
5588 | ||
5589 | case USE_COMPARE: | |
5590 | rewrite_use_compare (data, use, cand); | |
5591 | break; | |
5592 | ||
5593 | default: | |
1e128c5f | 5594 | gcc_unreachable (); |
8b11a64c | 5595 | } |
758cf3f2 | 5596 | mark_new_vars_to_rename (use->stmt); |
8b11a64c ZD |
5597 | } |
5598 | ||
5599 | /* Rewrite the uses using the selected induction variables. */ | |
5600 | ||
5601 | static void | |
5602 | rewrite_uses (struct ivopts_data *data) | |
5603 | { | |
5604 | unsigned i; | |
5605 | struct iv_cand *cand; | |
5606 | struct iv_use *use; | |
5607 | ||
5608 | for (i = 0; i < n_iv_uses (data); i++) | |
5609 | { | |
5610 | use = iv_use (data, i); | |
5611 | cand = use->selected; | |
1e128c5f | 5612 | gcc_assert (cand); |
8b11a64c ZD |
5613 | |
5614 | rewrite_use (data, use, cand); | |
5615 | } | |
5616 | } | |
5617 | ||
5618 | /* Removes the ivs that are not used after rewriting. */ | |
5619 | ||
5620 | static void | |
5621 | remove_unused_ivs (struct ivopts_data *data) | |
5622 | { | |
5623 | unsigned j; | |
87c476a2 | 5624 | bitmap_iterator bi; |
8b11a64c | 5625 | |
87c476a2 | 5626 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, j, bi) |
8b11a64c ZD |
5627 | { |
5628 | struct version_info *info; | |
5629 | ||
5630 | info = ver_info (data, j); | |
5631 | if (info->iv | |
5632 | && !zero_p (info->iv->step) | |
5633 | && !info->inv_id | |
5634 | && !info->iv->have_use_for | |
5635 | && !info->preserve_biv) | |
5636 | remove_statement (SSA_NAME_DEF_STMT (info->iv->ssa_name), true); | |
87c476a2 | 5637 | } |
8b11a64c ZD |
5638 | } |
5639 | ||
5640 | /* Frees data allocated by the optimization of a single loop. */ | |
5641 | ||
5642 | static void | |
5643 | free_loop_data (struct ivopts_data *data) | |
5644 | { | |
5645 | unsigned i, j; | |
87c476a2 | 5646 | bitmap_iterator bi; |
69ebd99d | 5647 | tree obj; |
8b11a64c | 5648 | |
ca4c3169 ZD |
5649 | htab_empty (data->niters); |
5650 | ||
87c476a2 | 5651 | EXECUTE_IF_SET_IN_BITMAP (data->relevant, 0, i, bi) |
8b11a64c ZD |
5652 | { |
5653 | struct version_info *info; | |
5654 | ||
5655 | info = ver_info (data, i); | |
5656 | if (info->iv) | |
5657 | free (info->iv); | |
5658 | info->iv = NULL; | |
5659 | info->has_nonlin_use = false; | |
5660 | info->preserve_biv = false; | |
5661 | info->inv_id = 0; | |
87c476a2 | 5662 | } |
8b11a64c | 5663 | bitmap_clear (data->relevant); |
b1b02be2 | 5664 | bitmap_clear (data->important_candidates); |
8b11a64c ZD |
5665 | |
5666 | for (i = 0; i < n_iv_uses (data); i++) | |
5667 | { | |
5668 | struct iv_use *use = iv_use (data, i); | |
5669 | ||
5670 | free (use->iv); | |
8bdbfff5 | 5671 | BITMAP_FREE (use->related_cands); |
8b11a64c ZD |
5672 | for (j = 0; j < use->n_map_members; j++) |
5673 | if (use->cost_map[j].depends_on) | |
8bdbfff5 | 5674 | BITMAP_FREE (use->cost_map[j].depends_on); |
8b11a64c ZD |
5675 | free (use->cost_map); |
5676 | free (use); | |
5677 | } | |
69ebd99d | 5678 | VEC_truncate (iv_use_p, data->iv_uses, 0); |
8b11a64c ZD |
5679 | |
5680 | for (i = 0; i < n_iv_cands (data); i++) | |
5681 | { | |
5682 | struct iv_cand *cand = iv_cand (data, i); | |
5683 | ||
5684 | if (cand->iv) | |
5685 | free (cand->iv); | |
9be872b7 ZD |
5686 | if (cand->depends_on) |
5687 | BITMAP_FREE (cand->depends_on); | |
8b11a64c ZD |
5688 | free (cand); |
5689 | } | |
69ebd99d | 5690 | VEC_truncate (iv_cand_p, data->iv_candidates, 0); |
8b11a64c ZD |
5691 | |
5692 | if (data->version_info_size < num_ssa_names) | |
5693 | { | |
5694 | data->version_info_size = 2 * num_ssa_names; | |
5695 | free (data->version_info); | |
5ed6ace5 | 5696 | data->version_info = XCNEWVEC (struct version_info, data->version_info_size); |
8b11a64c ZD |
5697 | } |
5698 | ||
5699 | data->max_inv_id = 0; | |
5700 | ||
69ebd99d KH |
5701 | for (i = 0; VEC_iterate (tree, decl_rtl_to_reset, i, obj); i++) |
5702 | SET_DECL_RTL (obj, NULL_RTX); | |
8b11a64c | 5703 | |
69ebd99d | 5704 | VEC_truncate (tree, decl_rtl_to_reset, 0); |
8b11a64c ZD |
5705 | } |
5706 | ||
5707 | /* Finalizes data structures used by the iv optimization pass. LOOPS is the | |
5708 | loop tree. */ | |
5709 | ||
5710 | static void | |
9a2ef6b8 | 5711 | tree_ssa_iv_optimize_finalize (struct ivopts_data *data) |
8b11a64c | 5712 | { |
8b11a64c ZD |
5713 | free_loop_data (data); |
5714 | free (data->version_info); | |
8bdbfff5 NS |
5715 | BITMAP_FREE (data->relevant); |
5716 | BITMAP_FREE (data->important_candidates); | |
ca4c3169 | 5717 | htab_delete (data->niters); |
8b11a64c | 5718 | |
69ebd99d KH |
5719 | VEC_free (tree, heap, decl_rtl_to_reset); |
5720 | VEC_free (iv_use_p, heap, data->iv_uses); | |
5721 | VEC_free (iv_cand_p, heap, data->iv_candidates); | |
8b11a64c ZD |
5722 | } |
5723 | ||
5724 | /* Optimizes the LOOP. Returns true if anything changed. */ | |
5725 | ||
5726 | static bool | |
5727 | tree_ssa_iv_optimize_loop (struct ivopts_data *data, struct loop *loop) | |
5728 | { | |
5729 | bool changed = false; | |
b1b02be2 | 5730 | struct iv_ca *iv_ca; |
8b11a64c ZD |
5731 | edge exit; |
5732 | ||
5733 | data->current_loop = loop; | |
5734 | ||
5735 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
5736 | { | |
5737 | fprintf (dump_file, "Processing loop %d\n", loop->num); | |
5738 | ||
5739 | exit = single_dom_exit (loop); | |
5740 | if (exit) | |
5741 | { | |
5742 | fprintf (dump_file, " single exit %d -> %d, exit condition ", | |
5743 | exit->src->index, exit->dest->index); | |
5744 | print_generic_expr (dump_file, last_stmt (exit->src), TDF_SLIM); | |
5745 | fprintf (dump_file, "\n"); | |
5746 | } | |
5747 | ||
5748 | fprintf (dump_file, "\n"); | |
5749 | } | |
5750 | ||
5751 | /* For each ssa name determines whether it behaves as an induction variable | |
5752 | in some loop. */ | |
5753 | if (!find_induction_variables (data)) | |
5754 | goto finish; | |
5755 | ||
5756 | /* Finds interesting uses (item 1). */ | |
5757 | find_interesting_uses (data); | |
5758 | if (n_iv_uses (data) > MAX_CONSIDERED_USES) | |
5759 | goto finish; | |
5760 | ||
5761 | /* Finds candidates for the induction variables (item 2). */ | |
5762 | find_iv_candidates (data); | |
5763 | ||
5764 | /* Calculates the costs (item 3, part 1). */ | |
5765 | determine_use_iv_costs (data); | |
5766 | determine_iv_costs (data); | |
5767 | determine_set_costs (data); | |
5768 | ||
5769 | /* Find the optimal set of induction variables (item 3, part 2). */ | |
b1b02be2 ZD |
5770 | iv_ca = find_optimal_iv_set (data); |
5771 | if (!iv_ca) | |
8b11a64c ZD |
5772 | goto finish; |
5773 | changed = true; | |
5774 | ||
5775 | /* Create the new induction variables (item 4, part 1). */ | |
b1b02be2 ZD |
5776 | create_new_ivs (data, iv_ca); |
5777 | iv_ca_free (&iv_ca); | |
8b11a64c ZD |
5778 | |
5779 | /* Rewrite the uses (item 4, part 2). */ | |
5780 | rewrite_uses (data); | |
5781 | ||
5782 | /* Remove the ivs that are unused after rewriting. */ | |
5783 | remove_unused_ivs (data); | |
5784 | ||
8b11a64c ZD |
5785 | /* We have changed the structure of induction variables; it might happen |
5786 | that definitions in the scev database refer to some of them that were | |
5787 | eliminated. */ | |
5788 | scev_reset (); | |
5789 | ||
5790 | finish: | |
5791 | free_loop_data (data); | |
5792 | ||
5793 | return changed; | |
5794 | } | |
5795 | ||
5796 | /* Main entry point. Optimizes induction variables in LOOPS. */ | |
5797 | ||
5798 | void | |
5799 | tree_ssa_iv_optimize (struct loops *loops) | |
5800 | { | |
5801 | struct loop *loop; | |
5802 | struct ivopts_data data; | |
5803 | ||
9a2ef6b8 | 5804 | tree_ssa_iv_optimize_init (&data); |
8b11a64c ZD |
5805 | |
5806 | /* Optimize the loops starting with the innermost ones. */ | |
5807 | loop = loops->tree_root; | |
5808 | while (loop->inner) | |
5809 | loop = loop->inner; | |
5810 | ||
8b11a64c ZD |
5811 | /* Scan the loops, inner ones first. */ |
5812 | while (loop != loops->tree_root) | |
5813 | { | |
8679c649 JH |
5814 | if (dump_file && (dump_flags & TDF_DETAILS)) |
5815 | flow_loop_dump (loop, dump_file, NULL, 1); | |
e9472263 ZD |
5816 | |
5817 | tree_ssa_iv_optimize_loop (&data, loop); | |
8b11a64c ZD |
5818 | |
5819 | if (loop->next) | |
5820 | { | |
5821 | loop = loop->next; | |
5822 | while (loop->inner) | |
5823 | loop = loop->inner; | |
5824 | } | |
5825 | else | |
5826 | loop = loop->outer; | |
5827 | } | |
5828 | ||
9a2ef6b8 | 5829 | tree_ssa_iv_optimize_finalize (&data); |
8b11a64c | 5830 | } |