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c2aa3ceb | 1 | /* RTL-level loop invariant motion. |
7cf0dbf3 | 2 | Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010 |
86482d6b | 3 | Free Software Foundation, Inc. |
c2aa3ceb | 4 | |
3a0ecac2 | 5 | This file is part of GCC. |
c2aa3ceb | 6 | |
3a0ecac2 | 7 | GCC is free software; you can redistribute it and/or modify it |
8 | under the terms of the GNU General Public License as published by the | |
8c4c00c1 | 9 | Free Software Foundation; either version 3, or (at your option) any |
3a0ecac2 | 10 | later version. |
c2aa3ceb | 11 | |
3a0ecac2 | 12 | GCC is distributed in the hope that it will be useful, but WITHOUT |
13 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 | for more details. | |
c2aa3ceb | 16 | |
3a0ecac2 | 17 | You should have received a copy of the GNU General Public License |
8c4c00c1 | 18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
3a0ecac2 | 20 | |
21 | /* This implements the loop invariant motion pass. It is very simple | |
1e5b92fa | 22 | (no calls, no loads/stores, etc.). This should be sufficient to cleanup |
23 | things like address arithmetics -- other more complicated invariants should | |
24 | be eliminated on GIMPLE either in tree-ssa-loop-im.c or in tree-ssa-pre.c. | |
c2aa3ceb | 25 | |
3a0ecac2 | 26 | We proceed loop by loop -- it is simpler than trying to handle things |
27 | globally and should not lose much. First we inspect all sets inside loop | |
28 | and create a dependency graph on insns (saying "to move this insn, you must | |
29 | also move the following insns"). | |
30 | ||
31 | We then need to determine what to move. We estimate the number of registers | |
32 | used and move as many invariants as possible while we still have enough free | |
33 | registers. We prefer the expensive invariants. | |
c2aa3ceb | 34 | |
3a0ecac2 | 35 | Then we move the selected invariants out of the loop, creating a new |
36 | temporaries for them if necessary. */ | |
37 | ||
38 | #include "config.h" | |
39 | #include "system.h" | |
40 | #include "coretypes.h" | |
41 | #include "tm.h" | |
e8eed2f8 | 42 | #include "hard-reg-set.h" |
3a0ecac2 | 43 | #include "rtl.h" |
4a77dc8c | 44 | #include "tm_p.h" |
42fe97ed | 45 | #include "obstack.h" |
3a0ecac2 | 46 | #include "basic-block.h" |
47 | #include "cfgloop.h" | |
48 | #include "expr.h" | |
3d6b8be7 | 49 | #include "recog.h" |
3a0ecac2 | 50 | #include "output.h" |
51 | #include "function.h" | |
52 | #include "flags.h" | |
53 | #include "df.h" | |
3d6b8be7 | 54 | #include "hashtab.h" |
a39b96b6 | 55 | #include "except.h" |
86482d6b | 56 | #include "params.h" |
e8eed2f8 | 57 | #include "regs.h" |
58 | #include "ira.h" | |
3a0ecac2 | 59 | |
60 | /* The data stored for the loop. */ | |
61 | ||
62 | struct loop_data | |
63 | { | |
64 | struct loop *outermost_exit; /* The outermost exit of the loop. */ | |
65 | bool has_call; /* True if the loop contains a call. */ | |
e8eed2f8 | 66 | /* Maximal register pressure inside loop for given register class |
66d9a7b9 | 67 | (defined only for the pressure classes). */ |
e8eed2f8 | 68 | int max_reg_pressure[N_REG_CLASSES]; |
69 | /* Loop regs referenced and live pseudo-registers. */ | |
70 | bitmap_head regs_ref; | |
71 | bitmap_head regs_live; | |
3a0ecac2 | 72 | }; |
73 | ||
74 | #define LOOP_DATA(LOOP) ((struct loop_data *) (LOOP)->aux) | |
75 | ||
76 | /* The description of an use. */ | |
77 | ||
78 | struct use | |
79 | { | |
80 | rtx *pos; /* Position of the use. */ | |
81 | rtx insn; /* The insn in that the use occurs. */ | |
68461c19 | 82 | unsigned addr_use_p; /* Whether the use occurs in an address. */ |
3a0ecac2 | 83 | struct use *next; /* Next use in the list. */ |
84 | }; | |
85 | ||
86 | /* The description of a def. */ | |
87 | ||
88 | struct def | |
89 | { | |
90 | struct use *uses; /* The list of uses that are uniquely reached | |
91 | by it. */ | |
92 | unsigned n_uses; /* Number of such uses. */ | |
68461c19 | 93 | unsigned n_addr_uses; /* Number of uses in addresses. */ |
3a0ecac2 | 94 | unsigned invno; /* The corresponding invariant. */ |
95 | }; | |
96 | ||
97 | /* The data stored for each invariant. */ | |
98 | ||
99 | struct invariant | |
100 | { | |
101 | /* The number of the invariant. */ | |
102 | unsigned invno; | |
103 | ||
3d6b8be7 | 104 | /* The number of the invariant with the same value. */ |
105 | unsigned eqto; | |
106 | ||
107 | /* If we moved the invariant out of the loop, the register that contains its | |
108 | value. */ | |
109 | rtx reg; | |
3a0ecac2 | 110 | |
e8eed2f8 | 111 | /* If we moved the invariant out of the loop, the original regno |
112 | that contained its value. */ | |
113 | int orig_regno; | |
114 | ||
3a0ecac2 | 115 | /* The definition of the invariant. */ |
116 | struct def *def; | |
117 | ||
118 | /* The insn in that it is defined. */ | |
119 | rtx insn; | |
120 | ||
121 | /* Whether it is always executed. */ | |
122 | bool always_executed; | |
123 | ||
124 | /* Whether to move the invariant. */ | |
125 | bool move; | |
126 | ||
68461c19 | 127 | /* Whether the invariant is cheap when used as an address. */ |
128 | bool cheap_address; | |
129 | ||
c2aa3ceb | 130 | /* Cost of the invariant. */ |
3a0ecac2 | 131 | unsigned cost; |
132 | ||
133 | /* The invariants it depends on. */ | |
134 | bitmap depends_on; | |
135 | ||
136 | /* Used for detecting already visited invariants during determining | |
137 | costs of movements. */ | |
138 | unsigned stamp; | |
139 | }; | |
140 | ||
e8eed2f8 | 141 | /* Currently processed loop. */ |
142 | static struct loop *curr_loop; | |
143 | ||
3072d30e | 144 | /* Table of invariants indexed by the df_ref uid field. */ |
145 | ||
146 | static unsigned int invariant_table_size = 0; | |
147 | static struct invariant ** invariant_table; | |
148 | ||
3d6b8be7 | 149 | /* Entry for hash table of invariant expressions. */ |
150 | ||
151 | struct invariant_expr_entry | |
152 | { | |
153 | /* The invariant. */ | |
154 | struct invariant *inv; | |
155 | ||
156 | /* Its value. */ | |
157 | rtx expr; | |
158 | ||
159 | /* Its mode. */ | |
160 | enum machine_mode mode; | |
161 | ||
162 | /* Its hash. */ | |
163 | hashval_t hash; | |
164 | }; | |
165 | ||
3a0ecac2 | 166 | /* The actual stamp for marking already visited invariants during determining |
167 | costs of movements. */ | |
168 | ||
169 | static unsigned actual_stamp; | |
170 | ||
703056c9 | 171 | typedef struct invariant *invariant_p; |
172 | ||
173 | DEF_VEC_P(invariant_p); | |
174 | DEF_VEC_ALLOC_P(invariant_p, heap); | |
175 | ||
3a0ecac2 | 176 | /* The invariants. */ |
177 | ||
703056c9 | 178 | static VEC(invariant_p,heap) *invariants; |
3a0ecac2 | 179 | |
3072d30e | 180 | /* Check the size of the invariant table and realloc if necessary. */ |
c2aa3ceb | 181 | |
48e1416a | 182 | static void |
3072d30e | 183 | check_invariant_table_size (void) |
184 | { | |
185 | if (invariant_table_size < DF_DEFS_TABLE_SIZE()) | |
186 | { | |
187 | unsigned int new_size = DF_DEFS_TABLE_SIZE () + (DF_DEFS_TABLE_SIZE () / 4); | |
4077bf7a | 188 | invariant_table = XRESIZEVEC (struct invariant *, invariant_table, new_size); |
48e1416a | 189 | memset (&invariant_table[invariant_table_size], 0, |
3072d30e | 190 | (new_size - invariant_table_size) * sizeof (struct rtx_iv *)); |
191 | invariant_table_size = new_size; | |
192 | } | |
193 | } | |
c2aa3ceb | 194 | |
3a0ecac2 | 195 | /* Test for possibility of invariantness of X. */ |
196 | ||
197 | static bool | |
198 | check_maybe_invariant (rtx x) | |
199 | { | |
200 | enum rtx_code code = GET_CODE (x); | |
201 | int i, j; | |
202 | const char *fmt; | |
203 | ||
204 | switch (code) | |
205 | { | |
206 | case CONST_INT: | |
207 | case CONST_DOUBLE: | |
e397ad8e | 208 | case CONST_FIXED: |
3a0ecac2 | 209 | case SYMBOL_REF: |
210 | case CONST: | |
211 | case LABEL_REF: | |
212 | return true; | |
213 | ||
214 | case PC: | |
215 | case CC0: | |
216 | case UNSPEC_VOLATILE: | |
217 | case CALL: | |
218 | return false; | |
219 | ||
220 | case REG: | |
221 | return true; | |
222 | ||
223 | case MEM: | |
224 | /* Load/store motion is done elsewhere. ??? Perhaps also add it here? | |
225 | It should not be hard, and might be faster than "elsewhere". */ | |
226 | ||
227 | /* Just handle the most trivial case where we load from an unchanging | |
228 | location (most importantly, pic tables). */ | |
13ecee21 | 229 | if (MEM_READONLY_P (x) && !MEM_VOLATILE_P (x)) |
3a0ecac2 | 230 | break; |
231 | ||
232 | return false; | |
233 | ||
234 | case ASM_OPERANDS: | |
235 | /* Don't mess with insns declared volatile. */ | |
236 | if (MEM_VOLATILE_P (x)) | |
237 | return false; | |
238 | break; | |
239 | ||
240 | default: | |
241 | break; | |
242 | } | |
243 | ||
244 | fmt = GET_RTX_FORMAT (code); | |
245 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
246 | { | |
247 | if (fmt[i] == 'e') | |
248 | { | |
249 | if (!check_maybe_invariant (XEXP (x, i))) | |
250 | return false; | |
251 | } | |
252 | else if (fmt[i] == 'E') | |
253 | { | |
254 | for (j = 0; j < XVECLEN (x, i); j++) | |
255 | if (!check_maybe_invariant (XVECEXP (x, i, j))) | |
256 | return false; | |
257 | } | |
258 | } | |
259 | ||
260 | return true; | |
261 | } | |
262 | ||
3d6b8be7 | 263 | /* Returns the invariant definition for USE, or NULL if USE is not |
264 | invariant. */ | |
265 | ||
266 | static struct invariant * | |
ed6e85ae | 267 | invariant_for_use (df_ref use) |
3d6b8be7 | 268 | { |
269 | struct df_link *defs; | |
ed6e85ae | 270 | df_ref def; |
158b6cc9 | 271 | basic_block bb = DF_REF_BB (use), def_bb; |
3d6b8be7 | 272 | |
ed6e85ae | 273 | if (DF_REF_FLAGS (use) & DF_REF_READ_WRITE) |
2e33cac5 | 274 | return NULL; |
275 | ||
3d6b8be7 | 276 | defs = DF_REF_CHAIN (use); |
277 | if (!defs || defs->next) | |
278 | return NULL; | |
279 | def = defs->ref; | |
3072d30e | 280 | check_invariant_table_size (); |
281 | if (!invariant_table[DF_REF_ID(def)]) | |
3d6b8be7 | 282 | return NULL; |
283 | ||
284 | def_bb = DF_REF_BB (def); | |
285 | if (!dominated_by_p (CDI_DOMINATORS, bb, def_bb)) | |
286 | return NULL; | |
3072d30e | 287 | return invariant_table[DF_REF_ID(def)]; |
3d6b8be7 | 288 | } |
289 | ||
290 | /* Computes hash value for invariant expression X in INSN. */ | |
291 | ||
292 | static hashval_t | |
293 | hash_invariant_expr_1 (rtx insn, rtx x) | |
294 | { | |
295 | enum rtx_code code = GET_CODE (x); | |
296 | int i, j; | |
297 | const char *fmt; | |
298 | hashval_t val = code; | |
299 | int do_not_record_p; | |
ed6e85ae | 300 | df_ref use; |
3d6b8be7 | 301 | struct invariant *inv; |
302 | ||
303 | switch (code) | |
304 | { | |
305 | case CONST_INT: | |
306 | case CONST_DOUBLE: | |
e397ad8e | 307 | case CONST_FIXED: |
3d6b8be7 | 308 | case SYMBOL_REF: |
309 | case CONST: | |
310 | case LABEL_REF: | |
311 | return hash_rtx (x, GET_MODE (x), &do_not_record_p, NULL, false); | |
312 | ||
313 | case REG: | |
3072d30e | 314 | use = df_find_use (insn, x); |
3d6b8be7 | 315 | if (!use) |
316 | return hash_rtx (x, GET_MODE (x), &do_not_record_p, NULL, false); | |
317 | inv = invariant_for_use (use); | |
318 | if (!inv) | |
319 | return hash_rtx (x, GET_MODE (x), &do_not_record_p, NULL, false); | |
320 | ||
321 | gcc_assert (inv->eqto != ~0u); | |
322 | return inv->eqto; | |
323 | ||
324 | default: | |
325 | break; | |
326 | } | |
327 | ||
328 | fmt = GET_RTX_FORMAT (code); | |
329 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
330 | { | |
331 | if (fmt[i] == 'e') | |
332 | val ^= hash_invariant_expr_1 (insn, XEXP (x, i)); | |
333 | else if (fmt[i] == 'E') | |
334 | { | |
335 | for (j = 0; j < XVECLEN (x, i); j++) | |
336 | val ^= hash_invariant_expr_1 (insn, XVECEXP (x, i, j)); | |
337 | } | |
5df640f6 | 338 | else if (fmt[i] == 'i' || fmt[i] == 'n') |
339 | val ^= XINT (x, i); | |
3d6b8be7 | 340 | } |
341 | ||
342 | return val; | |
343 | } | |
344 | ||
345 | /* Returns true if the invariant expressions E1 and E2 used in insns INSN1 | |
346 | and INSN2 have always the same value. */ | |
347 | ||
348 | static bool | |
349 | invariant_expr_equal_p (rtx insn1, rtx e1, rtx insn2, rtx e2) | |
350 | { | |
351 | enum rtx_code code = GET_CODE (e1); | |
352 | int i, j; | |
353 | const char *fmt; | |
ed6e85ae | 354 | df_ref use1, use2; |
3d6b8be7 | 355 | struct invariant *inv1 = NULL, *inv2 = NULL; |
356 | rtx sub1, sub2; | |
357 | ||
358 | /* If mode of only one of the operands is VOIDmode, it is not equivalent to | |
359 | the other one. If both are VOIDmode, we rely on the caller of this | |
360 | function to verify that their modes are the same. */ | |
361 | if (code != GET_CODE (e2) || GET_MODE (e1) != GET_MODE (e2)) | |
362 | return false; | |
363 | ||
364 | switch (code) | |
365 | { | |
366 | case CONST_INT: | |
367 | case CONST_DOUBLE: | |
e397ad8e | 368 | case CONST_FIXED: |
3d6b8be7 | 369 | case SYMBOL_REF: |
370 | case CONST: | |
371 | case LABEL_REF: | |
372 | return rtx_equal_p (e1, e2); | |
373 | ||
374 | case REG: | |
3072d30e | 375 | use1 = df_find_use (insn1, e1); |
376 | use2 = df_find_use (insn2, e2); | |
3d6b8be7 | 377 | if (use1) |
378 | inv1 = invariant_for_use (use1); | |
379 | if (use2) | |
380 | inv2 = invariant_for_use (use2); | |
381 | ||
382 | if (!inv1 && !inv2) | |
383 | return rtx_equal_p (e1, e2); | |
384 | ||
385 | if (!inv1 || !inv2) | |
386 | return false; | |
387 | ||
388 | gcc_assert (inv1->eqto != ~0u); | |
389 | gcc_assert (inv2->eqto != ~0u); | |
390 | return inv1->eqto == inv2->eqto; | |
391 | ||
392 | default: | |
393 | break; | |
394 | } | |
395 | ||
396 | fmt = GET_RTX_FORMAT (code); | |
397 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
398 | { | |
399 | if (fmt[i] == 'e') | |
400 | { | |
401 | sub1 = XEXP (e1, i); | |
402 | sub2 = XEXP (e2, i); | |
403 | ||
404 | if (!invariant_expr_equal_p (insn1, sub1, insn2, sub2)) | |
405 | return false; | |
406 | } | |
407 | ||
408 | else if (fmt[i] == 'E') | |
409 | { | |
410 | if (XVECLEN (e1, i) != XVECLEN (e2, i)) | |
411 | return false; | |
412 | ||
413 | for (j = 0; j < XVECLEN (e1, i); j++) | |
414 | { | |
415 | sub1 = XVECEXP (e1, i, j); | |
416 | sub2 = XVECEXP (e2, i, j); | |
417 | ||
418 | if (!invariant_expr_equal_p (insn1, sub1, insn2, sub2)) | |
419 | return false; | |
420 | } | |
421 | } | |
5df640f6 | 422 | else if (fmt[i] == 'i' || fmt[i] == 'n') |
423 | { | |
424 | if (XINT (e1, i) != XINT (e2, i)) | |
425 | return false; | |
426 | } | |
427 | /* Unhandled type of subexpression, we fail conservatively. */ | |
428 | else | |
429 | return false; | |
3d6b8be7 | 430 | } |
431 | ||
432 | return true; | |
433 | } | |
434 | ||
435 | /* Returns hash value for invariant expression entry E. */ | |
436 | ||
437 | static hashval_t | |
438 | hash_invariant_expr (const void *e) | |
439 | { | |
4077bf7a | 440 | const struct invariant_expr_entry *const entry = |
441 | (const struct invariant_expr_entry *) e; | |
3d6b8be7 | 442 | |
443 | return entry->hash; | |
444 | } | |
445 | ||
446 | /* Compares invariant expression entries E1 and E2. */ | |
447 | ||
448 | static int | |
449 | eq_invariant_expr (const void *e1, const void *e2) | |
450 | { | |
4077bf7a | 451 | const struct invariant_expr_entry *const entry1 = |
452 | (const struct invariant_expr_entry *) e1; | |
453 | const struct invariant_expr_entry *const entry2 = | |
454 | (const struct invariant_expr_entry *) e2; | |
3d6b8be7 | 455 | |
456 | if (entry1->mode != entry2->mode) | |
457 | return 0; | |
458 | ||
459 | return invariant_expr_equal_p (entry1->inv->insn, entry1->expr, | |
460 | entry2->inv->insn, entry2->expr); | |
461 | } | |
462 | ||
463 | /* Checks whether invariant with value EXPR in machine mode MODE is | |
464 | recorded in EQ. If this is the case, return the invariant. Otherwise | |
465 | insert INV to the table for this expression and return INV. */ | |
466 | ||
467 | static struct invariant * | |
468 | find_or_insert_inv (htab_t eq, rtx expr, enum machine_mode mode, | |
469 | struct invariant *inv) | |
470 | { | |
471 | hashval_t hash = hash_invariant_expr_1 (inv->insn, expr); | |
472 | struct invariant_expr_entry *entry; | |
473 | struct invariant_expr_entry pentry; | |
474 | PTR *slot; | |
475 | ||
476 | pentry.expr = expr; | |
477 | pentry.inv = inv; | |
478 | pentry.mode = mode; | |
479 | slot = htab_find_slot_with_hash (eq, &pentry, hash, INSERT); | |
4077bf7a | 480 | entry = (struct invariant_expr_entry *) *slot; |
3d6b8be7 | 481 | |
482 | if (entry) | |
483 | return entry->inv; | |
484 | ||
4c36ffe6 | 485 | entry = XNEW (struct invariant_expr_entry); |
3d6b8be7 | 486 | entry->inv = inv; |
487 | entry->expr = expr; | |
488 | entry->mode = mode; | |
489 | entry->hash = hash; | |
490 | *slot = entry; | |
491 | ||
492 | return inv; | |
493 | } | |
494 | ||
495 | /* Finds invariants identical to INV and records the equivalence. EQ is the | |
496 | hash table of the invariants. */ | |
497 | ||
498 | static void | |
499 | find_identical_invariants (htab_t eq, struct invariant *inv) | |
500 | { | |
501 | unsigned depno; | |
502 | bitmap_iterator bi; | |
503 | struct invariant *dep; | |
504 | rtx expr, set; | |
505 | enum machine_mode mode; | |
506 | ||
507 | if (inv->eqto != ~0u) | |
508 | return; | |
509 | ||
510 | EXECUTE_IF_SET_IN_BITMAP (inv->depends_on, 0, depno, bi) | |
511 | { | |
512 | dep = VEC_index (invariant_p, invariants, depno); | |
513 | find_identical_invariants (eq, dep); | |
514 | } | |
515 | ||
516 | set = single_set (inv->insn); | |
517 | expr = SET_SRC (set); | |
518 | mode = GET_MODE (expr); | |
519 | if (mode == VOIDmode) | |
520 | mode = GET_MODE (SET_DEST (set)); | |
521 | inv->eqto = find_or_insert_inv (eq, expr, mode, inv)->invno; | |
522 | ||
523 | if (dump_file && inv->eqto != inv->invno) | |
524 | fprintf (dump_file, | |
5ed26a34 | 525 | "Invariant %d is equivalent to invariant %d.\n", |
3d6b8be7 | 526 | inv->invno, inv->eqto); |
527 | } | |
528 | ||
529 | /* Find invariants with the same value and record the equivalences. */ | |
530 | ||
531 | static void | |
532 | merge_identical_invariants (void) | |
533 | { | |
534 | unsigned i; | |
535 | struct invariant *inv; | |
536 | htab_t eq = htab_create (VEC_length (invariant_p, invariants), | |
537 | hash_invariant_expr, eq_invariant_expr, free); | |
538 | ||
48148244 | 539 | FOR_EACH_VEC_ELT (invariant_p, invariants, i, inv) |
3d6b8be7 | 540 | find_identical_invariants (eq, inv); |
541 | ||
542 | htab_delete (eq); | |
543 | } | |
544 | ||
3a0ecac2 | 545 | /* Determines the basic blocks inside LOOP that are always executed and |
546 | stores their bitmap to ALWAYS_REACHED. MAY_EXIT is a bitmap of | |
547 | basic blocks that may either exit the loop, or contain the call that | |
548 | does not have to return. BODY is body of the loop obtained by | |
549 | get_loop_body_in_dom_order. */ | |
550 | ||
551 | static void | |
552 | compute_always_reached (struct loop *loop, basic_block *body, | |
553 | bitmap may_exit, bitmap always_reached) | |
554 | { | |
555 | unsigned i; | |
556 | ||
557 | for (i = 0; i < loop->num_nodes; i++) | |
558 | { | |
559 | if (dominated_by_p (CDI_DOMINATORS, loop->latch, body[i])) | |
560 | bitmap_set_bit (always_reached, i); | |
561 | ||
562 | if (bitmap_bit_p (may_exit, i)) | |
563 | return; | |
564 | } | |
565 | } | |
566 | ||
567 | /* Finds exits out of the LOOP with body BODY. Marks blocks in that we may | |
568 | exit the loop by cfg edge to HAS_EXIT and MAY_EXIT. In MAY_EXIT | |
569 | additionally mark blocks that may exit due to a call. */ | |
570 | ||
571 | static void | |
572 | find_exits (struct loop *loop, basic_block *body, | |
573 | bitmap may_exit, bitmap has_exit) | |
574 | { | |
575 | unsigned i; | |
cd665a06 | 576 | edge_iterator ei; |
3a0ecac2 | 577 | edge e; |
578 | struct loop *outermost_exit = loop, *aexit; | |
579 | bool has_call = false; | |
580 | rtx insn; | |
581 | ||
582 | for (i = 0; i < loop->num_nodes; i++) | |
583 | { | |
584 | if (body[i]->loop_father == loop) | |
585 | { | |
586 | FOR_BB_INSNS (body[i], insn) | |
587 | { | |
6d7dc5b9 | 588 | if (CALL_P (insn) |
9c2a0c05 | 589 | && (RTL_LOOPING_CONST_OR_PURE_CALL_P (insn) |
590 | || !RTL_CONST_OR_PURE_CALL_P (insn))) | |
3a0ecac2 | 591 | { |
592 | has_call = true; | |
593 | bitmap_set_bit (may_exit, i); | |
594 | break; | |
595 | } | |
596 | } | |
597 | ||
cd665a06 | 598 | FOR_EACH_EDGE (e, ei, body[i]->succs) |
3a0ecac2 | 599 | { |
600 | if (flow_bb_inside_loop_p (loop, e->dest)) | |
601 | continue; | |
602 | ||
603 | bitmap_set_bit (may_exit, i); | |
604 | bitmap_set_bit (has_exit, i); | |
605 | outermost_exit = find_common_loop (outermost_exit, | |
606 | e->dest->loop_father); | |
607 | } | |
608 | continue; | |
609 | } | |
c2aa3ceb | 610 | |
3a0ecac2 | 611 | /* Use the data stored for the subloop to decide whether we may exit |
612 | through it. It is sufficient to do this for header of the loop, | |
613 | as other basic blocks inside it must be dominated by it. */ | |
614 | if (body[i]->loop_father->header != body[i]) | |
615 | continue; | |
616 | ||
617 | if (LOOP_DATA (body[i]->loop_father)->has_call) | |
618 | { | |
619 | has_call = true; | |
620 | bitmap_set_bit (may_exit, i); | |
621 | } | |
622 | aexit = LOOP_DATA (body[i]->loop_father)->outermost_exit; | |
623 | if (aexit != loop) | |
624 | { | |
625 | bitmap_set_bit (may_exit, i); | |
626 | bitmap_set_bit (has_exit, i); | |
627 | ||
628 | if (flow_loop_nested_p (aexit, outermost_exit)) | |
629 | outermost_exit = aexit; | |
630 | } | |
631 | } | |
632 | ||
e8eed2f8 | 633 | if (loop->aux == NULL) |
634 | { | |
635 | loop->aux = xcalloc (1, sizeof (struct loop_data)); | |
636 | bitmap_initialize (&LOOP_DATA (loop)->regs_ref, ®_obstack); | |
637 | bitmap_initialize (&LOOP_DATA (loop)->regs_live, ®_obstack); | |
638 | } | |
3a0ecac2 | 639 | LOOP_DATA (loop)->outermost_exit = outermost_exit; |
640 | LOOP_DATA (loop)->has_call = has_call; | |
641 | } | |
642 | ||
643 | /* Check whether we may assign a value to X from a register. */ | |
644 | ||
645 | static bool | |
646 | may_assign_reg_p (rtx x) | |
647 | { | |
51fb5608 | 648 | return (GET_MODE (x) != VOIDmode |
a436996a | 649 | && GET_MODE (x) != BLKmode |
51fb5608 | 650 | && can_copy_p (GET_MODE (x)) |
2c5cdc40 | 651 | && (!REG_P (x) |
652 | || !HARD_REGISTER_P (x) | |
653 | || REGNO_REG_CLASS (REGNO (x)) != NO_REGS)); | |
3a0ecac2 | 654 | } |
655 | ||
c2aa3ceb | 656 | /* Finds definitions that may correspond to invariants in LOOP with body |
657 | BODY. */ | |
3a0ecac2 | 658 | |
659 | static void | |
c2aa3ceb | 660 | find_defs (struct loop *loop, basic_block *body) |
3a0ecac2 | 661 | { |
662 | unsigned i; | |
27335ffd | 663 | bitmap blocks = BITMAP_ALLOC (NULL); |
3a0ecac2 | 664 | |
665 | for (i = 0; i < loop->num_nodes; i++) | |
666 | bitmap_set_bit (blocks, body[i]->index); | |
667 | ||
3072d30e | 668 | df_remove_problem (df_chain); |
669 | df_process_deferred_rescans (); | |
670 | df_chain_add_problem (DF_UD_CHAIN); | |
671 | df_set_blocks (blocks); | |
672 | df_analyze (); | |
673 | ||
674 | if (dump_file) | |
675 | { | |
774f8797 | 676 | df_dump_region (dump_file); |
3072d30e | 677 | fprintf (dump_file, "*****starting processing of loop ******\n"); |
678 | print_rtl_with_bb (dump_file, get_insns ()); | |
679 | fprintf (dump_file, "*****ending processing of loop ******\n"); | |
680 | } | |
681 | check_invariant_table_size (); | |
682 | ||
27335ffd | 683 | BITMAP_FREE (blocks); |
3a0ecac2 | 684 | } |
685 | ||
686 | /* Creates a new invariant for definition DEF in INSN, depending on invariants | |
687 | in DEPENDS_ON. ALWAYS_EXECUTED is true if the insn is always executed, | |
3d6b8be7 | 688 | unless the program ends due to a function call. The newly created invariant |
689 | is returned. */ | |
3a0ecac2 | 690 | |
3d6b8be7 | 691 | static struct invariant * |
3a0ecac2 | 692 | create_new_invariant (struct def *def, rtx insn, bitmap depends_on, |
693 | bool always_executed) | |
694 | { | |
4c36ffe6 | 695 | struct invariant *inv = XNEW (struct invariant); |
3a0ecac2 | 696 | rtx set = single_set (insn); |
f529eb25 | 697 | bool speed = optimize_bb_for_speed_p (BLOCK_FOR_INSN (insn)); |
3a0ecac2 | 698 | |
699 | inv->def = def; | |
700 | inv->always_executed = always_executed; | |
701 | inv->depends_on = depends_on; | |
702 | ||
703 | /* If the set is simple, usually by moving it we move the whole store out of | |
704 | the loop. Otherwise we save only cost of the computation. */ | |
705 | if (def) | |
68461c19 | 706 | { |
b72d459f | 707 | inv->cost = set_rtx_cost (set, speed); |
21a9b734 | 708 | /* ??? Try to determine cheapness of address computation. Unfortunately |
709 | the address cost is only a relative measure, we can't really compare | |
710 | it with any absolute number, but only with other address costs. | |
711 | But here we don't have any other addresses, so compare with a magic | |
712 | number anyway. It has to be large enough to not regress PR33928 | |
713 | (by avoiding to move reg+8,reg+16,reg+24 invariants), but small | |
714 | enough to not regress 410.bwaves either (by still moving reg+reg | |
715 | invariants). | |
716 | See http://gcc.gnu.org/ml/gcc-patches/2009-10/msg01210.html . */ | |
68461c19 | 717 | inv->cheap_address = address_cost (SET_SRC (set), word_mode, |
bd1a81f7 | 718 | ADDR_SPACE_GENERIC, speed) < 3; |
68461c19 | 719 | } |
3a0ecac2 | 720 | else |
68461c19 | 721 | { |
7013e87c | 722 | inv->cost = set_src_cost (SET_SRC (set), speed); |
68461c19 | 723 | inv->cheap_address = false; |
724 | } | |
3a0ecac2 | 725 | |
726 | inv->move = false; | |
3d6b8be7 | 727 | inv->reg = NULL_RTX; |
e8eed2f8 | 728 | inv->orig_regno = -1; |
3a0ecac2 | 729 | inv->stamp = 0; |
730 | inv->insn = insn; | |
731 | ||
703056c9 | 732 | inv->invno = VEC_length (invariant_p, invariants); |
3d6b8be7 | 733 | inv->eqto = ~0u; |
3a0ecac2 | 734 | if (def) |
735 | def->invno = inv->invno; | |
703056c9 | 736 | VEC_safe_push (invariant_p, heap, invariants, inv); |
3a0ecac2 | 737 | |
738 | if (dump_file) | |
739 | { | |
740 | fprintf (dump_file, | |
741 | "Set in insn %d is invariant (%d), cost %d, depends on ", | |
742 | INSN_UID (insn), inv->invno, inv->cost); | |
743 | dump_bitmap (dump_file, inv->depends_on); | |
744 | } | |
3d6b8be7 | 745 | |
746 | return inv; | |
3a0ecac2 | 747 | } |
748 | ||
749 | /* Record USE at DEF. */ | |
750 | ||
751 | static void | |
68461c19 | 752 | record_use (struct def *def, df_ref use) |
3a0ecac2 | 753 | { |
4c36ffe6 | 754 | struct use *u = XNEW (struct use); |
3a0ecac2 | 755 | |
68461c19 | 756 | u->pos = DF_REF_REAL_LOC (use); |
757 | u->insn = DF_REF_INSN (use); | |
758 | u->addr_use_p = (DF_REF_TYPE (use) == DF_REF_REG_MEM_LOAD | |
5c83cd34 | 759 | || DF_REF_TYPE (use) == DF_REF_REG_MEM_STORE); |
3a0ecac2 | 760 | u->next = def->uses; |
761 | def->uses = u; | |
762 | def->n_uses++; | |
68461c19 | 763 | if (u->addr_use_p) |
764 | def->n_addr_uses++; | |
3a0ecac2 | 765 | } |
766 | ||
3072d30e | 767 | /* Finds the invariants USE depends on and store them to the DEPENDS_ON |
768 | bitmap. Returns true if all dependencies of USE are known to be | |
2e33cac5 | 769 | loop invariants, false otherwise. */ |
3a0ecac2 | 770 | |
771 | static bool | |
ed6e85ae | 772 | check_dependency (basic_block bb, df_ref use, bitmap depends_on) |
3a0ecac2 | 773 | { |
ed6e85ae | 774 | df_ref def; |
3072d30e | 775 | basic_block def_bb; |
e011eba9 | 776 | struct df_link *defs; |
3a0ecac2 | 777 | struct def *def_data; |
3d6b8be7 | 778 | struct invariant *inv; |
48e1416a | 779 | |
ed6e85ae | 780 | if (DF_REF_FLAGS (use) & DF_REF_READ_WRITE) |
3072d30e | 781 | return false; |
48e1416a | 782 | |
3072d30e | 783 | defs = DF_REF_CHAIN (use); |
784 | if (!defs) | |
785 | return true; | |
48e1416a | 786 | |
3072d30e | 787 | if (defs->next) |
788 | return false; | |
48e1416a | 789 | |
3072d30e | 790 | def = defs->ref; |
791 | check_invariant_table_size (); | |
792 | inv = invariant_table[DF_REF_ID(def)]; | |
793 | if (!inv) | |
794 | return false; | |
48e1416a | 795 | |
3072d30e | 796 | def_data = inv->def; |
797 | gcc_assert (def_data != NULL); | |
48e1416a | 798 | |
3072d30e | 799 | def_bb = DF_REF_BB (def); |
800 | /* Note that in case bb == def_bb, we know that the definition | |
801 | dominates insn, because def has invariant_table[DF_REF_ID(def)] | |
802 | defined and we process the insns in the basic block bb | |
803 | sequentially. */ | |
804 | if (!dominated_by_p (CDI_DOMINATORS, bb, def_bb)) | |
805 | return false; | |
48e1416a | 806 | |
3072d30e | 807 | bitmap_set_bit (depends_on, def_data->invno); |
808 | return true; | |
809 | } | |
3d6b8be7 | 810 | |
3d6b8be7 | 811 | |
3072d30e | 812 | /* Finds the invariants INSN depends on and store them to the DEPENDS_ON |
813 | bitmap. Returns true if all dependencies of INSN are known to be | |
814 | loop invariants, false otherwise. */ | |
3a0ecac2 | 815 | |
3072d30e | 816 | static bool |
817 | check_dependencies (rtx insn, bitmap depends_on) | |
818 | { | |
158b6cc9 | 819 | struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn); |
ed6e85ae | 820 | df_ref *use_rec; |
3072d30e | 821 | basic_block bb = BLOCK_FOR_INSN (insn); |
3a0ecac2 | 822 | |
158b6cc9 | 823 | for (use_rec = DF_INSN_INFO_USES (insn_info); *use_rec; use_rec++) |
3072d30e | 824 | if (!check_dependency (bb, *use_rec, depends_on)) |
825 | return false; | |
158b6cc9 | 826 | for (use_rec = DF_INSN_INFO_EQ_USES (insn_info); *use_rec; use_rec++) |
3072d30e | 827 | if (!check_dependency (bb, *use_rec, depends_on)) |
828 | return false; | |
48e1416a | 829 | |
3a0ecac2 | 830 | return true; |
831 | } | |
832 | ||
833 | /* Finds invariant in INSN. ALWAYS_REACHED is true if the insn is always | |
834 | executed. ALWAYS_EXECUTED is true if the insn is always executed, | |
c2aa3ceb | 835 | unless the program ends due to a function call. */ |
3a0ecac2 | 836 | |
837 | static void | |
c2aa3ceb | 838 | find_invariant_insn (rtx insn, bool always_reached, bool always_executed) |
3a0ecac2 | 839 | { |
ed6e85ae | 840 | df_ref ref; |
3a0ecac2 | 841 | struct def *def; |
842 | bitmap depends_on; | |
843 | rtx set, dest; | |
844 | bool simple = true; | |
3d6b8be7 | 845 | struct invariant *inv; |
3a0ecac2 | 846 | |
d9da8b4c | 847 | #ifdef HAVE_cc0 |
848 | /* We can't move a CC0 setter without the user. */ | |
849 | if (sets_cc0_p (insn)) | |
850 | return; | |
851 | #endif | |
852 | ||
3a0ecac2 | 853 | set = single_set (insn); |
854 | if (!set) | |
855 | return; | |
856 | dest = SET_DEST (set); | |
857 | ||
1c14a50e | 858 | if (!REG_P (dest) |
3a0ecac2 | 859 | || HARD_REGISTER_P (dest)) |
860 | simple = false; | |
861 | ||
2c5cdc40 | 862 | if (!may_assign_reg_p (SET_DEST (set)) |
863 | || !check_maybe_invariant (SET_SRC (set))) | |
3a0ecac2 | 864 | return; |
865 | ||
a39b96b6 | 866 | /* If the insn can throw exception, we cannot move it at all without changing |
867 | cfg. */ | |
868 | if (can_throw_internal (insn)) | |
869 | return; | |
3a0ecac2 | 870 | |
a39b96b6 | 871 | /* We cannot make trapping insn executed, unless it was executed before. */ |
0eee494e | 872 | if (may_trap_or_fault_p (PATTERN (insn)) && !always_reached) |
a39b96b6 | 873 | return; |
3a0ecac2 | 874 | |
27335ffd | 875 | depends_on = BITMAP_ALLOC (NULL); |
c2aa3ceb | 876 | if (!check_dependencies (insn, depends_on)) |
3a0ecac2 | 877 | { |
27335ffd | 878 | BITMAP_FREE (depends_on); |
3a0ecac2 | 879 | return; |
880 | } | |
881 | ||
882 | if (simple) | |
4c36ffe6 | 883 | def = XCNEW (struct def); |
3a0ecac2 | 884 | else |
885 | def = NULL; | |
886 | ||
3d6b8be7 | 887 | inv = create_new_invariant (def, insn, depends_on, always_executed); |
888 | ||
889 | if (simple) | |
890 | { | |
3072d30e | 891 | ref = df_find_def (insn, dest); |
892 | check_invariant_table_size (); | |
893 | invariant_table[DF_REF_ID(ref)] = inv; | |
3d6b8be7 | 894 | } |
3a0ecac2 | 895 | } |
896 | ||
c2aa3ceb | 897 | /* Record registers used in INSN that have a unique invariant definition. */ |
3a0ecac2 | 898 | |
899 | static void | |
c2aa3ceb | 900 | record_uses (rtx insn) |
3a0ecac2 | 901 | { |
158b6cc9 | 902 | struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn); |
ed6e85ae | 903 | df_ref *use_rec; |
3d6b8be7 | 904 | struct invariant *inv; |
905 | ||
158b6cc9 | 906 | for (use_rec = DF_INSN_INFO_USES (insn_info); *use_rec; use_rec++) |
3072d30e | 907 | { |
ed6e85ae | 908 | df_ref use = *use_rec; |
3072d30e | 909 | inv = invariant_for_use (use); |
910 | if (inv) | |
68461c19 | 911 | record_use (inv->def, use); |
3072d30e | 912 | } |
158b6cc9 | 913 | for (use_rec = DF_INSN_INFO_EQ_USES (insn_info); *use_rec; use_rec++) |
3a0ecac2 | 914 | { |
ed6e85ae | 915 | df_ref use = *use_rec; |
3d6b8be7 | 916 | inv = invariant_for_use (use); |
917 | if (inv) | |
68461c19 | 918 | record_use (inv->def, use); |
3a0ecac2 | 919 | } |
920 | } | |
921 | ||
922 | /* Finds invariants in INSN. ALWAYS_REACHED is true if the insn is always | |
923 | executed. ALWAYS_EXECUTED is true if the insn is always executed, | |
c2aa3ceb | 924 | unless the program ends due to a function call. */ |
3a0ecac2 | 925 | |
926 | static void | |
c2aa3ceb | 927 | find_invariants_insn (rtx insn, bool always_reached, bool always_executed) |
3a0ecac2 | 928 | { |
c2aa3ceb | 929 | find_invariant_insn (insn, always_reached, always_executed); |
930 | record_uses (insn); | |
3a0ecac2 | 931 | } |
932 | ||
933 | /* Finds invariants in basic block BB. ALWAYS_REACHED is true if the | |
934 | basic block is always executed. ALWAYS_EXECUTED is true if the basic | |
935 | block is always executed, unless the program ends due to a function | |
c2aa3ceb | 936 | call. */ |
3a0ecac2 | 937 | |
938 | static void | |
c2aa3ceb | 939 | find_invariants_bb (basic_block bb, bool always_reached, bool always_executed) |
3a0ecac2 | 940 | { |
941 | rtx insn; | |
942 | ||
943 | FOR_BB_INSNS (bb, insn) | |
944 | { | |
9845d120 | 945 | if (!NONDEBUG_INSN_P (insn)) |
3a0ecac2 | 946 | continue; |
947 | ||
c2aa3ceb | 948 | find_invariants_insn (insn, always_reached, always_executed); |
3a0ecac2 | 949 | |
950 | if (always_reached | |
6d7dc5b9 | 951 | && CALL_P (insn) |
9c2a0c05 | 952 | && (RTL_LOOPING_CONST_OR_PURE_CALL_P (insn) |
953 | || ! RTL_CONST_OR_PURE_CALL_P (insn))) | |
3a0ecac2 | 954 | always_reached = false; |
955 | } | |
956 | } | |
957 | ||
958 | /* Finds invariants in LOOP with body BODY. ALWAYS_REACHED is the bitmap of | |
959 | basic blocks in BODY that are always executed. ALWAYS_EXECUTED is the | |
960 | bitmap of basic blocks in BODY that are always executed unless the program | |
c2aa3ceb | 961 | ends due to a function call. */ |
3a0ecac2 | 962 | |
963 | static void | |
964 | find_invariants_body (struct loop *loop, basic_block *body, | |
c2aa3ceb | 965 | bitmap always_reached, bitmap always_executed) |
3a0ecac2 | 966 | { |
967 | unsigned i; | |
968 | ||
969 | for (i = 0; i < loop->num_nodes; i++) | |
970 | find_invariants_bb (body[i], | |
971 | bitmap_bit_p (always_reached, i), | |
c2aa3ceb | 972 | bitmap_bit_p (always_executed, i)); |
3a0ecac2 | 973 | } |
974 | ||
c2aa3ceb | 975 | /* Finds invariants in LOOP. */ |
3a0ecac2 | 976 | |
977 | static void | |
c2aa3ceb | 978 | find_invariants (struct loop *loop) |
3a0ecac2 | 979 | { |
27335ffd | 980 | bitmap may_exit = BITMAP_ALLOC (NULL); |
981 | bitmap always_reached = BITMAP_ALLOC (NULL); | |
982 | bitmap has_exit = BITMAP_ALLOC (NULL); | |
983 | bitmap always_executed = BITMAP_ALLOC (NULL); | |
3a0ecac2 | 984 | basic_block *body = get_loop_body_in_dom_order (loop); |
985 | ||
986 | find_exits (loop, body, may_exit, has_exit); | |
987 | compute_always_reached (loop, body, may_exit, always_reached); | |
988 | compute_always_reached (loop, body, has_exit, always_executed); | |
989 | ||
c2aa3ceb | 990 | find_defs (loop, body); |
991 | find_invariants_body (loop, body, always_reached, always_executed); | |
3d6b8be7 | 992 | merge_identical_invariants (); |
3a0ecac2 | 993 | |
27335ffd | 994 | BITMAP_FREE (always_reached); |
995 | BITMAP_FREE (always_executed); | |
996 | BITMAP_FREE (may_exit); | |
997 | BITMAP_FREE (has_exit); | |
3a0ecac2 | 998 | free (body); |
999 | } | |
1000 | ||
1001 | /* Frees a list of uses USE. */ | |
1002 | ||
1003 | static void | |
1004 | free_use_list (struct use *use) | |
1005 | { | |
1006 | struct use *next; | |
1007 | ||
1008 | for (; use; use = next) | |
1009 | { | |
1010 | next = use->next; | |
1011 | free (use); | |
1012 | } | |
1013 | } | |
1014 | ||
66d9a7b9 | 1015 | /* Return pressure class and number of hard registers (through *NREGS) |
e8eed2f8 | 1016 | for destination of INSN. */ |
1017 | static enum reg_class | |
66d9a7b9 | 1018 | get_pressure_class_and_nregs (rtx insn, int *nregs) |
e8eed2f8 | 1019 | { |
1020 | rtx reg; | |
66d9a7b9 | 1021 | enum reg_class pressure_class; |
e8eed2f8 | 1022 | rtx set = single_set (insn); |
48e1416a | 1023 | |
e8eed2f8 | 1024 | /* Considered invariant insns have only one set. */ |
1025 | gcc_assert (set != NULL_RTX); | |
1026 | reg = SET_DEST (set); | |
1027 | if (GET_CODE (reg) == SUBREG) | |
1028 | reg = SUBREG_REG (reg); | |
1029 | if (MEM_P (reg)) | |
1030 | { | |
1031 | *nregs = 0; | |
66d9a7b9 | 1032 | pressure_class = NO_REGS; |
e8eed2f8 | 1033 | } |
1034 | else | |
1035 | { | |
1036 | if (! REG_P (reg)) | |
1037 | reg = NULL_RTX; | |
1038 | if (reg == NULL_RTX) | |
66d9a7b9 | 1039 | pressure_class = GENERAL_REGS; |
e8eed2f8 | 1040 | else |
66d9a7b9 | 1041 | { |
1042 | pressure_class = reg_allocno_class (REGNO (reg)); | |
1043 | pressure_class = ira_pressure_class_translate[pressure_class]; | |
1044 | } | |
1045 | *nregs | |
1046 | = ira_reg_class_max_nregs[pressure_class][GET_MODE (SET_SRC (set))]; | |
e8eed2f8 | 1047 | } |
66d9a7b9 | 1048 | return pressure_class; |
e8eed2f8 | 1049 | } |
1050 | ||
3a0ecac2 | 1051 | /* Calculates cost and number of registers needed for moving invariant INV |
1052 | out of the loop and stores them to *COST and *REGS_NEEDED. */ | |
1053 | ||
1054 | static void | |
1055 | get_inv_cost (struct invariant *inv, int *comp_cost, unsigned *regs_needed) | |
1056 | { | |
e8eed2f8 | 1057 | int i, acomp_cost; |
1058 | unsigned aregs_needed[N_REG_CLASSES]; | |
3a0ecac2 | 1059 | unsigned depno; |
1060 | struct invariant *dep; | |
0cc4271a | 1061 | bitmap_iterator bi; |
3a0ecac2 | 1062 | |
3d6b8be7 | 1063 | /* Find the representative of the class of the equivalent invariants. */ |
1064 | inv = VEC_index (invariant_p, invariants, inv->eqto); | |
1065 | ||
3a0ecac2 | 1066 | *comp_cost = 0; |
e8eed2f8 | 1067 | if (! flag_ira_loop_pressure) |
1068 | regs_needed[0] = 0; | |
1069 | else | |
1070 | { | |
66d9a7b9 | 1071 | for (i = 0; i < ira_pressure_classes_num; i++) |
1072 | regs_needed[ira_pressure_classes[i]] = 0; | |
e8eed2f8 | 1073 | } |
1074 | ||
3a0ecac2 | 1075 | if (inv->move |
1076 | || inv->stamp == actual_stamp) | |
1077 | return; | |
1078 | inv->stamp = actual_stamp; | |
1079 | ||
e8eed2f8 | 1080 | if (! flag_ira_loop_pressure) |
1081 | regs_needed[0]++; | |
1082 | else | |
1083 | { | |
1084 | int nregs; | |
66d9a7b9 | 1085 | enum reg_class pressure_class; |
e8eed2f8 | 1086 | |
66d9a7b9 | 1087 | pressure_class = get_pressure_class_and_nregs (inv->insn, &nregs); |
1088 | regs_needed[pressure_class] += nregs; | |
e8eed2f8 | 1089 | } |
1090 | ||
68461c19 | 1091 | if (!inv->cheap_address |
1092 | || inv->def->n_addr_uses < inv->def->n_uses) | |
1093 | (*comp_cost) += inv->cost; | |
3a0ecac2 | 1094 | |
e207fd7a | 1095 | #ifdef STACK_REGS |
1096 | { | |
1097 | /* Hoisting constant pool constants into stack regs may cost more than | |
1098 | just single register. On x87, the balance is affected both by the | |
334ec2d8 | 1099 | small number of FP registers, and by its register stack organization, |
e207fd7a | 1100 | that forces us to add compensation code in and around the loop to |
1101 | shuffle the operands to the top of stack before use, and pop them | |
1102 | from the stack after the loop finishes. | |
1103 | ||
1104 | To model this effect, we increase the number of registers needed for | |
1105 | stack registers by two: one register push, and one register pop. | |
1106 | This usually has the effect that FP constant loads from the constant | |
1107 | pool are not moved out of the loop. | |
1108 | ||
1109 | Note that this also means that dependent invariants can not be moved. | |
1110 | However, the primary purpose of this pass is to move loop invariant | |
1111 | address arithmetic out of loops, and address arithmetic that depends | |
1112 | on floating point constants is unlikely to ever occur. */ | |
1113 | rtx set = single_set (inv->insn); | |
1114 | if (set | |
e8eed2f8 | 1115 | && IS_STACK_MODE (GET_MODE (SET_SRC (set))) |
1116 | && constant_pool_constant_p (SET_SRC (set))) | |
1117 | { | |
1118 | if (flag_ira_loop_pressure) | |
66d9a7b9 | 1119 | regs_needed[ira_stack_reg_pressure_class] += 2; |
e8eed2f8 | 1120 | else |
1121 | regs_needed[0] += 2; | |
1122 | } | |
e207fd7a | 1123 | } |
1124 | #endif | |
1125 | ||
0cc4271a | 1126 | EXECUTE_IF_SET_IN_BITMAP (inv->depends_on, 0, depno, bi) |
3a0ecac2 | 1127 | { |
e8eed2f8 | 1128 | bool check_p; |
1129 | ||
703056c9 | 1130 | dep = VEC_index (invariant_p, invariants, depno); |
3a0ecac2 | 1131 | |
e8eed2f8 | 1132 | get_inv_cost (dep, &acomp_cost, aregs_needed); |
3a0ecac2 | 1133 | |
e8eed2f8 | 1134 | if (! flag_ira_loop_pressure) |
1135 | check_p = aregs_needed[0] != 0; | |
1136 | else | |
1137 | { | |
66d9a7b9 | 1138 | for (i = 0; i < ira_pressure_classes_num; i++) |
1139 | if (aregs_needed[ira_pressure_classes[i]] != 0) | |
e8eed2f8 | 1140 | break; |
66d9a7b9 | 1141 | check_p = i < ira_pressure_classes_num; |
e8eed2f8 | 1142 | } |
1143 | if (check_p | |
3a0ecac2 | 1144 | /* We need to check always_executed, since if the original value of |
1145 | the invariant may be preserved, we may need to keep it in a | |
1146 | separate register. TODO check whether the register has an | |
1147 | use outside of the loop. */ | |
1148 | && dep->always_executed | |
1149 | && !dep->def->uses->next) | |
1150 | { | |
1151 | /* If this is a single use, after moving the dependency we will not | |
1152 | need a new register. */ | |
e8eed2f8 | 1153 | if (! flag_ira_loop_pressure) |
1154 | aregs_needed[0]--; | |
1155 | else | |
1156 | { | |
1157 | int nregs; | |
66d9a7b9 | 1158 | enum reg_class pressure_class; |
e8eed2f8 | 1159 | |
66d9a7b9 | 1160 | pressure_class = get_pressure_class_and_nregs (inv->insn, &nregs); |
1161 | aregs_needed[pressure_class] -= nregs; | |
e8eed2f8 | 1162 | } |
3a0ecac2 | 1163 | } |
1164 | ||
e8eed2f8 | 1165 | if (! flag_ira_loop_pressure) |
1166 | regs_needed[0] += aregs_needed[0]; | |
1167 | else | |
1168 | { | |
66d9a7b9 | 1169 | for (i = 0; i < ira_pressure_classes_num; i++) |
1170 | regs_needed[ira_pressure_classes[i]] | |
1171 | += aregs_needed[ira_pressure_classes[i]]; | |
e8eed2f8 | 1172 | } |
3a0ecac2 | 1173 | (*comp_cost) += acomp_cost; |
0cc4271a | 1174 | } |
3a0ecac2 | 1175 | } |
1176 | ||
1177 | /* Calculates gain for eliminating invariant INV. REGS_USED is the number | |
25153338 | 1178 | of registers used in the loop, NEW_REGS is the number of new variables |
1179 | already added due to the invariant motion. The number of registers needed | |
a6b74a67 | 1180 | for it is stored in *REGS_NEEDED. SPEED and CALL_P are flags passed |
1181 | through to estimate_reg_pressure_cost. */ | |
3a0ecac2 | 1182 | |
1183 | static int | |
1184 | gain_for_invariant (struct invariant *inv, unsigned *regs_needed, | |
a6b74a67 | 1185 | unsigned *new_regs, unsigned regs_used, |
1186 | bool speed, bool call_p) | |
3a0ecac2 | 1187 | { |
1188 | int comp_cost, size_cost; | |
1189 | ||
3a0ecac2 | 1190 | actual_stamp++; |
1191 | ||
e8eed2f8 | 1192 | get_inv_cost (inv, &comp_cost, regs_needed); |
1193 | ||
1194 | if (! flag_ira_loop_pressure) | |
1195 | { | |
1196 | size_cost = (estimate_reg_pressure_cost (new_regs[0] + regs_needed[0], | |
a6b74a67 | 1197 | regs_used, speed, call_p) |
e8eed2f8 | 1198 | - estimate_reg_pressure_cost (new_regs[0], |
a6b74a67 | 1199 | regs_used, speed, call_p)); |
e8eed2f8 | 1200 | } |
1201 | else | |
1202 | { | |
1203 | int i; | |
66d9a7b9 | 1204 | enum reg_class pressure_class; |
e8eed2f8 | 1205 | |
66d9a7b9 | 1206 | for (i = 0; i < ira_pressure_classes_num; i++) |
e8eed2f8 | 1207 | { |
66d9a7b9 | 1208 | pressure_class = ira_pressure_classes[i]; |
1209 | if ((int) new_regs[pressure_class] | |
1210 | + (int) regs_needed[pressure_class] | |
1211 | + LOOP_DATA (curr_loop)->max_reg_pressure[pressure_class] | |
e8eed2f8 | 1212 | + IRA_LOOP_RESERVED_REGS |
1072fecf | 1213 | > ira_class_hard_regs_num[pressure_class]) |
e8eed2f8 | 1214 | break; |
1215 | } | |
66d9a7b9 | 1216 | if (i < ira_pressure_classes_num) |
e8eed2f8 | 1217 | /* There will be register pressure excess and we want not to |
1218 | make this loop invariant motion. All loop invariants with | |
1219 | non-positive gains will be rejected in function | |
1220 | find_invariants_to_move. Therefore we return the negative | |
1221 | number here. | |
1222 | ||
1223 | One could think that this rejects also expensive loop | |
1224 | invariant motions and this will hurt code performance. | |
1225 | However numerous experiments with different heuristics | |
1226 | taking invariant cost into account did not confirm this | |
1227 | assumption. There are possible explanations for this | |
1228 | result: | |
1229 | o probably all expensive invariants were already moved out | |
1230 | of the loop by PRE and gimple invariant motion pass. | |
1231 | o expensive invariant execution will be hidden by insn | |
1232 | scheduling or OOO processor hardware because usually such | |
1233 | invariants have a lot of freedom to be executed | |
1234 | out-of-order. | |
1235 | Another reason for ignoring invariant cost vs spilling cost | |
1236 | heuristics is also in difficulties to evaluate accurately | |
1237 | spill cost at this stage. */ | |
1238 | return -1; | |
1239 | else | |
1240 | size_cost = 0; | |
1241 | } | |
3a0ecac2 | 1242 | |
1243 | return comp_cost - size_cost; | |
1244 | } | |
1245 | ||
1246 | /* Finds invariant with best gain for moving. Returns the gain, stores | |
1247 | the invariant in *BEST and number of registers needed for it to | |
25153338 | 1248 | *REGS_NEEDED. REGS_USED is the number of registers used in the loop. |
1249 | NEW_REGS is the number of new variables already added due to invariant | |
1250 | motion. */ | |
3a0ecac2 | 1251 | |
1252 | static int | |
1253 | best_gain_for_invariant (struct invariant **best, unsigned *regs_needed, | |
a6b74a67 | 1254 | unsigned *new_regs, unsigned regs_used, |
1255 | bool speed, bool call_p) | |
3a0ecac2 | 1256 | { |
1257 | struct invariant *inv; | |
e8eed2f8 | 1258 | int i, gain = 0, again; |
1259 | unsigned aregs_needed[N_REG_CLASSES], invno; | |
3a0ecac2 | 1260 | |
48148244 | 1261 | FOR_EACH_VEC_ELT (invariant_p, invariants, invno, inv) |
3a0ecac2 | 1262 | { |
3a0ecac2 | 1263 | if (inv->move) |
1264 | continue; | |
1265 | ||
3d6b8be7 | 1266 | /* Only consider the "representatives" of equivalent invariants. */ |
1267 | if (inv->eqto != inv->invno) | |
1268 | continue; | |
1269 | ||
e8eed2f8 | 1270 | again = gain_for_invariant (inv, aregs_needed, new_regs, regs_used, |
a6b74a67 | 1271 | speed, call_p); |
3a0ecac2 | 1272 | if (again > gain) |
1273 | { | |
1274 | gain = again; | |
1275 | *best = inv; | |
e8eed2f8 | 1276 | if (! flag_ira_loop_pressure) |
1277 | regs_needed[0] = aregs_needed[0]; | |
1278 | else | |
1279 | { | |
66d9a7b9 | 1280 | for (i = 0; i < ira_pressure_classes_num; i++) |
1281 | regs_needed[ira_pressure_classes[i]] | |
1282 | = aregs_needed[ira_pressure_classes[i]]; | |
e8eed2f8 | 1283 | } |
3a0ecac2 | 1284 | } |
1285 | } | |
1286 | ||
1287 | return gain; | |
1288 | } | |
1289 | ||
1290 | /* Marks invariant INVNO and all its dependencies for moving. */ | |
1291 | ||
1292 | static void | |
e8eed2f8 | 1293 | set_move_mark (unsigned invno, int gain) |
3a0ecac2 | 1294 | { |
703056c9 | 1295 | struct invariant *inv = VEC_index (invariant_p, invariants, invno); |
0cc4271a | 1296 | bitmap_iterator bi; |
3a0ecac2 | 1297 | |
3d6b8be7 | 1298 | /* Find the representative of the class of the equivalent invariants. */ |
1299 | inv = VEC_index (invariant_p, invariants, inv->eqto); | |
1300 | ||
3a0ecac2 | 1301 | if (inv->move) |
1302 | return; | |
1303 | inv->move = true; | |
1304 | ||
1305 | if (dump_file) | |
e8eed2f8 | 1306 | { |
1307 | if (gain >= 0) | |
1308 | fprintf (dump_file, "Decided to move invariant %d -- gain %d\n", | |
1309 | invno, gain); | |
1310 | else | |
1311 | fprintf (dump_file, "Decided to move dependent invariant %d\n", | |
1312 | invno); | |
1313 | }; | |
3a0ecac2 | 1314 | |
0cc4271a | 1315 | EXECUTE_IF_SET_IN_BITMAP (inv->depends_on, 0, invno, bi) |
1316 | { | |
e8eed2f8 | 1317 | set_move_mark (invno, -1); |
0cc4271a | 1318 | } |
3a0ecac2 | 1319 | } |
1320 | ||
c2aa3ceb | 1321 | /* Determines which invariants to move. */ |
3a0ecac2 | 1322 | |
1323 | static void | |
a6b74a67 | 1324 | find_invariants_to_move (bool speed, bool call_p) |
3a0ecac2 | 1325 | { |
e8eed2f8 | 1326 | int gain; |
1327 | unsigned i, regs_used, regs_needed[N_REG_CLASSES], new_regs[N_REG_CLASSES]; | |
3a0ecac2 | 1328 | struct invariant *inv = NULL; |
1329 | ||
703056c9 | 1330 | if (!VEC_length (invariant_p, invariants)) |
3a0ecac2 | 1331 | return; |
1332 | ||
e8eed2f8 | 1333 | if (flag_ira_loop_pressure) |
48e1416a | 1334 | /* REGS_USED is actually never used when the flag is on. */ |
e8eed2f8 | 1335 | regs_used = 0; |
1336 | else | |
1337 | /* We do not really do a good job in estimating number of | |
1338 | registers used; we put some initial bound here to stand for | |
1339 | induction variables etc. that we do not detect. */ | |
3a0ecac2 | 1340 | { |
e8eed2f8 | 1341 | unsigned int n_regs = DF_REG_SIZE (df); |
1342 | ||
1343 | regs_used = 2; | |
48e1416a | 1344 | |
e8eed2f8 | 1345 | for (i = 0; i < n_regs; i++) |
3a0ecac2 | 1346 | { |
e8eed2f8 | 1347 | if (!DF_REGNO_FIRST_DEF (i) && DF_REGNO_LAST_USE (i)) |
1348 | { | |
1349 | /* This is a value that is used but not changed inside loop. */ | |
1350 | regs_used++; | |
1351 | } | |
3a0ecac2 | 1352 | } |
1353 | } | |
1354 | ||
e8eed2f8 | 1355 | if (! flag_ira_loop_pressure) |
1356 | new_regs[0] = regs_needed[0] = 0; | |
1357 | else | |
3a0ecac2 | 1358 | { |
66d9a7b9 | 1359 | for (i = 0; (int) i < ira_pressure_classes_num; i++) |
1360 | new_regs[ira_pressure_classes[i]] = 0; | |
e8eed2f8 | 1361 | } |
1362 | while ((gain = best_gain_for_invariant (&inv, regs_needed, | |
a6b74a67 | 1363 | new_regs, regs_used, |
1364 | speed, call_p)) > 0) | |
e8eed2f8 | 1365 | { |
1366 | set_move_mark (inv->invno, gain); | |
1367 | if (! flag_ira_loop_pressure) | |
1368 | new_regs[0] += regs_needed[0]; | |
1369 | else | |
1370 | { | |
66d9a7b9 | 1371 | for (i = 0; (int) i < ira_pressure_classes_num; i++) |
1372 | new_regs[ira_pressure_classes[i]] | |
1373 | += regs_needed[ira_pressure_classes[i]]; | |
e8eed2f8 | 1374 | } |
3a0ecac2 | 1375 | } |
1376 | } | |
1377 | ||
cc6541e2 | 1378 | /* Replace the uses, reached by the definition of invariant INV, by REG. |
1379 | ||
1380 | IN_GROUP is nonzero if this is part of a group of changes that must be | |
1381 | performed as a group. In that case, the changes will be stored. The | |
1382 | function `apply_change_group' will validate and apply the changes. */ | |
1383 | ||
1384 | static int | |
1385 | replace_uses (struct invariant *inv, rtx reg, bool in_group) | |
1386 | { | |
1387 | /* Replace the uses we know to be dominated. It saves work for copy | |
1388 | propagation, and also it is necessary so that dependent invariants | |
1389 | are computed right. */ | |
1390 | if (inv->def) | |
1391 | { | |
1392 | struct use *use; | |
1393 | for (use = inv->def->uses; use; use = use->next) | |
1394 | validate_change (use->insn, use->pos, reg, true); | |
1395 | ||
1396 | /* If we aren't part of a larger group, apply the changes now. */ | |
1397 | if (!in_group) | |
1398 | return apply_change_group (); | |
1399 | } | |
1400 | ||
1401 | return 1; | |
1402 | } | |
1403 | ||
1e41d0e2 | 1404 | /* Move invariant INVNO out of the LOOP. Returns true if this succeeds, false |
1405 | otherwise. */ | |
1406 | ||
1407 | static bool | |
c2aa3ceb | 1408 | move_invariant_reg (struct loop *loop, unsigned invno) |
3a0ecac2 | 1409 | { |
703056c9 | 1410 | struct invariant *inv = VEC_index (invariant_p, invariants, invno); |
3d6b8be7 | 1411 | struct invariant *repr = VEC_index (invariant_p, invariants, inv->eqto); |
3a0ecac2 | 1412 | unsigned i; |
1413 | basic_block preheader = loop_preheader_edge (loop)->src; | |
c69c2a10 | 1414 | rtx reg, set, dest, note; |
0cc4271a | 1415 | bitmap_iterator bi; |
cc6541e2 | 1416 | int regno = -1; |
3a0ecac2 | 1417 | |
1e41d0e2 | 1418 | if (inv->reg) |
1419 | return true; | |
1420 | if (!repr->move) | |
1421 | return false; | |
cc6541e2 | 1422 | |
3d6b8be7 | 1423 | /* If this is a representative of the class of equivalent invariants, |
1424 | really move the invariant. Otherwise just replace its use with | |
1425 | the register used for the representative. */ | |
1426 | if (inv == repr) | |
3a0ecac2 | 1427 | { |
3d6b8be7 | 1428 | if (inv->depends_on) |
3a0ecac2 | 1429 | { |
3d6b8be7 | 1430 | EXECUTE_IF_SET_IN_BITMAP (inv->depends_on, 0, i, bi) |
1431 | { | |
1e41d0e2 | 1432 | if (!move_invariant_reg (loop, i)) |
1433 | goto fail; | |
3d6b8be7 | 1434 | } |
0cc4271a | 1435 | } |
3a0ecac2 | 1436 | |
3d6b8be7 | 1437 | /* Move the set out of the loop. If the set is always executed (we could |
cc6541e2 | 1438 | omit this condition if we know that the register is unused outside of |
1439 | the loop, but it does not seem worth finding out) and it has no uses | |
1440 | that would not be dominated by it, we may just move it (TODO). | |
1441 | Otherwise we need to create a temporary register. */ | |
3d6b8be7 | 1442 | set = single_set (inv->insn); |
e8eed2f8 | 1443 | reg = dest = SET_DEST (set); |
1444 | if (GET_CODE (reg) == SUBREG) | |
1445 | reg = SUBREG_REG (reg); | |
1446 | if (REG_P (reg)) | |
1447 | regno = REGNO (reg); | |
1448 | ||
ae12ddda | 1449 | reg = gen_reg_rtx_and_attrs (dest); |
3d6b8be7 | 1450 | |
c69c2a10 | 1451 | /* Try replacing the destination by a new pseudoregister. */ |
cc6541e2 | 1452 | validate_change (inv->insn, &SET_DEST (set), reg, true); |
1453 | ||
1454 | /* As well as all the dominated uses. */ | |
1455 | replace_uses (inv, reg, true); | |
1456 | ||
1457 | /* And validate all the changes. */ | |
1458 | if (!apply_change_group ()) | |
c69c2a10 | 1459 | goto fail; |
c69c2a10 | 1460 | |
1461 | emit_insn_after (gen_move_insn (dest, reg), inv->insn); | |
1462 | reorder_insns (inv->insn, inv->insn, BB_END (preheader)); | |
1463 | ||
2521c084 | 1464 | /* If there is a REG_EQUAL note on the insn we just moved, and the |
1465 | insn is in a basic block that is not always executed or the note | |
1466 | contains something for which we don't know the invariant status, | |
1467 | the note may no longer be valid after we move the insn. Note that | |
1468 | uses in REG_EQUAL notes are taken into account in the computation | |
1469 | of invariants, so it is safe to retain the note even if it contains | |
1470 | register references for which we know the invariant status. */ | |
1471 | if ((note = find_reg_note (inv->insn, REG_EQUAL, NULL_RTX)) | |
1472 | && (!inv->always_executed | |
1473 | || !check_maybe_invariant (XEXP (note, 0)))) | |
c69c2a10 | 1474 | remove_note (inv->insn, note); |
e363ebc7 | 1475 | } |
1476 | else | |
1477 | { | |
1e41d0e2 | 1478 | if (!move_invariant_reg (loop, repr->invno)) |
1479 | goto fail; | |
3d6b8be7 | 1480 | reg = repr->reg; |
e8eed2f8 | 1481 | regno = repr->orig_regno; |
cc6541e2 | 1482 | if (!replace_uses (inv, reg, false)) |
1483 | goto fail; | |
3d6b8be7 | 1484 | set = single_set (inv->insn); |
e011eba9 | 1485 | emit_insn_after (gen_move_insn (SET_DEST (set), reg), inv->insn); |
1486 | delete_insn (inv->insn); | |
e363ebc7 | 1487 | } |
3a0ecac2 | 1488 | |
3d6b8be7 | 1489 | inv->reg = reg; |
e8eed2f8 | 1490 | inv->orig_regno = regno; |
3d6b8be7 | 1491 | |
1e41d0e2 | 1492 | return true; |
1493 | ||
1494 | fail: | |
1495 | /* If we failed, clear move flag, so that we do not try to move inv | |
1496 | again. */ | |
1497 | if (dump_file) | |
1498 | fprintf (dump_file, "Failed to move invariant %d\n", invno); | |
1499 | inv->move = false; | |
1500 | inv->reg = NULL_RTX; | |
e8eed2f8 | 1501 | inv->orig_regno = -1; |
3072d30e | 1502 | |
1e41d0e2 | 1503 | return false; |
3a0ecac2 | 1504 | } |
1505 | ||
1506 | /* Move selected invariant out of the LOOP. Newly created regs are marked | |
c2aa3ceb | 1507 | in TEMPORARY_REGS. */ |
3a0ecac2 | 1508 | |
1509 | static void | |
c2aa3ceb | 1510 | move_invariants (struct loop *loop) |
3a0ecac2 | 1511 | { |
1512 | struct invariant *inv; | |
1513 | unsigned i; | |
1514 | ||
48148244 | 1515 | FOR_EACH_VEC_ELT (invariant_p, invariants, i, inv) |
3d6b8be7 | 1516 | move_invariant_reg (loop, i); |
e8eed2f8 | 1517 | if (flag_ira_loop_pressure && resize_reg_info ()) |
1518 | { | |
48148244 | 1519 | FOR_EACH_VEC_ELT (invariant_p, invariants, i, inv) |
e8eed2f8 | 1520 | if (inv->reg != NULL_RTX) |
1521 | { | |
1522 | if (inv->orig_regno >= 0) | |
1523 | setup_reg_classes (REGNO (inv->reg), | |
1524 | reg_preferred_class (inv->orig_regno), | |
1525 | reg_alternate_class (inv->orig_regno), | |
66d9a7b9 | 1526 | reg_allocno_class (inv->orig_regno)); |
e8eed2f8 | 1527 | else |
1528 | setup_reg_classes (REGNO (inv->reg), | |
1529 | GENERAL_REGS, NO_REGS, GENERAL_REGS); | |
1530 | } | |
1531 | } | |
3a0ecac2 | 1532 | } |
1533 | ||
1534 | /* Initializes invariant motion data. */ | |
1535 | ||
1536 | static void | |
1537 | init_inv_motion_data (void) | |
1538 | { | |
1539 | actual_stamp = 1; | |
1540 | ||
703056c9 | 1541 | invariants = VEC_alloc (invariant_p, heap, 100); |
3a0ecac2 | 1542 | } |
1543 | ||
c2aa3ceb | 1544 | /* Frees the data allocated by invariant motion. */ |
3a0ecac2 | 1545 | |
1546 | static void | |
c2aa3ceb | 1547 | free_inv_motion_data (void) |
3a0ecac2 | 1548 | { |
1549 | unsigned i; | |
1550 | struct def *def; | |
1551 | struct invariant *inv; | |
1552 | ||
3072d30e | 1553 | check_invariant_table_size (); |
1554 | for (i = 0; i < DF_DEFS_TABLE_SIZE (); i++) | |
3a0ecac2 | 1555 | { |
3072d30e | 1556 | inv = invariant_table[i]; |
1557 | if (inv) | |
1558 | { | |
1559 | def = inv->def; | |
1560 | gcc_assert (def != NULL); | |
48e1416a | 1561 | |
3072d30e | 1562 | free_use_list (def->uses); |
1563 | free (def); | |
1564 | invariant_table[i] = NULL; | |
1565 | } | |
3a0ecac2 | 1566 | } |
1567 | ||
48148244 | 1568 | FOR_EACH_VEC_ELT (invariant_p, invariants, i, inv) |
3a0ecac2 | 1569 | { |
27335ffd | 1570 | BITMAP_FREE (inv->depends_on); |
3a0ecac2 | 1571 | free (inv); |
1572 | } | |
703056c9 | 1573 | VEC_free (invariant_p, heap, invariants); |
3a0ecac2 | 1574 | } |
1575 | ||
c2aa3ceb | 1576 | /* Move the invariants out of the LOOP. */ |
3a0ecac2 | 1577 | |
1578 | static void | |
c2aa3ceb | 1579 | move_single_loop_invariants (struct loop *loop) |
3a0ecac2 | 1580 | { |
1581 | init_inv_motion_data (); | |
1582 | ||
c2aa3ceb | 1583 | find_invariants (loop); |
a6b74a67 | 1584 | find_invariants_to_move (optimize_loop_for_speed_p (loop), |
1585 | LOOP_DATA (loop)->has_call); | |
c2aa3ceb | 1586 | move_invariants (loop); |
3a0ecac2 | 1587 | |
c2aa3ceb | 1588 | free_inv_motion_data (); |
3a0ecac2 | 1589 | } |
1590 | ||
1591 | /* Releases the auxiliary data for LOOP. */ | |
1592 | ||
1593 | static void | |
1594 | free_loop_data (struct loop *loop) | |
1595 | { | |
1596 | struct loop_data *data = LOOP_DATA (loop); | |
8311e9d2 | 1597 | if (!data) |
1598 | return; | |
3a0ecac2 | 1599 | |
e8eed2f8 | 1600 | bitmap_clear (&LOOP_DATA (loop)->regs_ref); |
1601 | bitmap_clear (&LOOP_DATA (loop)->regs_live); | |
3a0ecac2 | 1602 | free (data); |
1603 | loop->aux = NULL; | |
1604 | } | |
1605 | ||
e8eed2f8 | 1606 | \f |
1607 | ||
1608 | /* Registers currently living. */ | |
1609 | static bitmap_head curr_regs_live; | |
1610 | ||
66d9a7b9 | 1611 | /* Current reg pressure for each pressure class. */ |
e8eed2f8 | 1612 | static int curr_reg_pressure[N_REG_CLASSES]; |
1613 | ||
1614 | /* Record all regs that are set in any one insn. Communication from | |
1615 | mark_reg_{store,clobber} and global_conflicts. Asm can refer to | |
1616 | all hard-registers. */ | |
1617 | static rtx regs_set[(FIRST_PSEUDO_REGISTER > MAX_RECOG_OPERANDS | |
1618 | ? FIRST_PSEUDO_REGISTER : MAX_RECOG_OPERANDS) * 2]; | |
1619 | /* Number of regs stored in the previous array. */ | |
1620 | static int n_regs_set; | |
1621 | ||
66d9a7b9 | 1622 | /* Return pressure class and number of needed hard registers (through |
48e1416a | 1623 | *NREGS) of register REGNO. */ |
e8eed2f8 | 1624 | static enum reg_class |
66d9a7b9 | 1625 | get_regno_pressure_class (int regno, int *nregs) |
e8eed2f8 | 1626 | { |
1627 | if (regno >= FIRST_PSEUDO_REGISTER) | |
1628 | { | |
66d9a7b9 | 1629 | enum reg_class pressure_class; |
e8eed2f8 | 1630 | |
66d9a7b9 | 1631 | pressure_class = reg_allocno_class (regno); |
1632 | pressure_class = ira_pressure_class_translate[pressure_class]; | |
1633 | *nregs | |
1634 | = ira_reg_class_max_nregs[pressure_class][PSEUDO_REGNO_MODE (regno)]; | |
1635 | return pressure_class; | |
e8eed2f8 | 1636 | } |
1637 | else if (! TEST_HARD_REG_BIT (ira_no_alloc_regs, regno) | |
1638 | && ! TEST_HARD_REG_BIT (eliminable_regset, regno)) | |
1639 | { | |
1640 | *nregs = 1; | |
66d9a7b9 | 1641 | return ira_pressure_class_translate[REGNO_REG_CLASS (regno)]; |
e8eed2f8 | 1642 | } |
1643 | else | |
1644 | { | |
1645 | *nregs = 0; | |
1646 | return NO_REGS; | |
1647 | } | |
1648 | } | |
1649 | ||
1650 | /* Increase (if INCR_P) or decrease current register pressure for | |
1651 | register REGNO. */ | |
1652 | static void | |
1653 | change_pressure (int regno, bool incr_p) | |
1654 | { | |
1655 | int nregs; | |
66d9a7b9 | 1656 | enum reg_class pressure_class; |
e8eed2f8 | 1657 | |
66d9a7b9 | 1658 | pressure_class = get_regno_pressure_class (regno, &nregs); |
e8eed2f8 | 1659 | if (! incr_p) |
66d9a7b9 | 1660 | curr_reg_pressure[pressure_class] -= nregs; |
e8eed2f8 | 1661 | else |
1662 | { | |
66d9a7b9 | 1663 | curr_reg_pressure[pressure_class] += nregs; |
1664 | if (LOOP_DATA (curr_loop)->max_reg_pressure[pressure_class] | |
1665 | < curr_reg_pressure[pressure_class]) | |
1666 | LOOP_DATA (curr_loop)->max_reg_pressure[pressure_class] | |
1667 | = curr_reg_pressure[pressure_class]; | |
e8eed2f8 | 1668 | } |
1669 | } | |
1670 | ||
1671 | /* Mark REGNO birth. */ | |
1672 | static void | |
1673 | mark_regno_live (int regno) | |
1674 | { | |
1675 | struct loop *loop; | |
1676 | ||
1677 | for (loop = curr_loop; | |
1678 | loop != current_loops->tree_root; | |
1679 | loop = loop_outer (loop)) | |
1680 | bitmap_set_bit (&LOOP_DATA (loop)->regs_live, regno); | |
6ef9bbe0 | 1681 | if (!bitmap_set_bit (&curr_regs_live, regno)) |
e8eed2f8 | 1682 | return; |
e8eed2f8 | 1683 | change_pressure (regno, true); |
1684 | } | |
1685 | ||
1686 | /* Mark REGNO death. */ | |
1687 | static void | |
1688 | mark_regno_death (int regno) | |
1689 | { | |
6ef9bbe0 | 1690 | if (! bitmap_clear_bit (&curr_regs_live, regno)) |
e8eed2f8 | 1691 | return; |
e8eed2f8 | 1692 | change_pressure (regno, false); |
1693 | } | |
1694 | ||
1695 | /* Mark setting register REG. */ | |
1696 | static void | |
1697 | mark_reg_store (rtx reg, const_rtx setter ATTRIBUTE_UNUSED, | |
1698 | void *data ATTRIBUTE_UNUSED) | |
1699 | { | |
1700 | int regno; | |
1701 | ||
1702 | if (GET_CODE (reg) == SUBREG) | |
1703 | reg = SUBREG_REG (reg); | |
1704 | ||
1705 | if (! REG_P (reg)) | |
1706 | return; | |
1707 | ||
1708 | regs_set[n_regs_set++] = reg; | |
1709 | ||
1710 | regno = REGNO (reg); | |
1711 | ||
1712 | if (regno >= FIRST_PSEUDO_REGISTER) | |
1713 | mark_regno_live (regno); | |
1714 | else | |
1715 | { | |
1716 | int last = regno + hard_regno_nregs[regno][GET_MODE (reg)]; | |
1717 | ||
1718 | while (regno < last) | |
1719 | { | |
1720 | mark_regno_live (regno); | |
1721 | regno++; | |
1722 | } | |
1723 | } | |
1724 | } | |
1725 | ||
1726 | /* Mark clobbering register REG. */ | |
1727 | static void | |
1728 | mark_reg_clobber (rtx reg, const_rtx setter, void *data) | |
1729 | { | |
1730 | if (GET_CODE (setter) == CLOBBER) | |
1731 | mark_reg_store (reg, setter, data); | |
1732 | } | |
1733 | ||
1734 | /* Mark register REG death. */ | |
1735 | static void | |
1736 | mark_reg_death (rtx reg) | |
1737 | { | |
1738 | int regno = REGNO (reg); | |
1739 | ||
1740 | if (regno >= FIRST_PSEUDO_REGISTER) | |
1741 | mark_regno_death (regno); | |
1742 | else | |
1743 | { | |
1744 | int last = regno + hard_regno_nregs[regno][GET_MODE (reg)]; | |
1745 | ||
1746 | while (regno < last) | |
1747 | { | |
1748 | mark_regno_death (regno); | |
1749 | regno++; | |
1750 | } | |
1751 | } | |
1752 | } | |
1753 | ||
1754 | /* Mark occurrence of registers in X for the current loop. */ | |
1755 | static void | |
1756 | mark_ref_regs (rtx x) | |
1757 | { | |
1758 | RTX_CODE code; | |
1759 | int i; | |
1760 | const char *fmt; | |
1761 | ||
1762 | if (!x) | |
1763 | return; | |
1764 | ||
1765 | code = GET_CODE (x); | |
1766 | if (code == REG) | |
1767 | { | |
1768 | struct loop *loop; | |
48e1416a | 1769 | |
e8eed2f8 | 1770 | for (loop = curr_loop; |
1771 | loop != current_loops->tree_root; | |
1772 | loop = loop_outer (loop)) | |
1773 | bitmap_set_bit (&LOOP_DATA (loop)->regs_ref, REGNO (x)); | |
1774 | return; | |
1775 | } | |
1776 | ||
1777 | fmt = GET_RTX_FORMAT (code); | |
1778 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
1779 | if (fmt[i] == 'e') | |
1780 | mark_ref_regs (XEXP (x, i)); | |
1781 | else if (fmt[i] == 'E') | |
1782 | { | |
1783 | int j; | |
48e1416a | 1784 | |
e8eed2f8 | 1785 | for (j = 0; j < XVECLEN (x, i); j++) |
1786 | mark_ref_regs (XVECEXP (x, i, j)); | |
1787 | } | |
1788 | } | |
1789 | ||
1790 | /* Calculate register pressure in the loops. */ | |
1791 | static void | |
1792 | calculate_loop_reg_pressure (void) | |
1793 | { | |
1794 | int i; | |
1795 | unsigned int j; | |
1796 | bitmap_iterator bi; | |
1797 | basic_block bb; | |
1798 | rtx insn, link; | |
1799 | struct loop *loop, *parent; | |
1800 | loop_iterator li; | |
1801 | ||
1802 | FOR_EACH_LOOP (li, loop, 0) | |
1803 | if (loop->aux == NULL) | |
1804 | { | |
1805 | loop->aux = xcalloc (1, sizeof (struct loop_data)); | |
1806 | bitmap_initialize (&LOOP_DATA (loop)->regs_ref, ®_obstack); | |
1807 | bitmap_initialize (&LOOP_DATA (loop)->regs_live, ®_obstack); | |
1808 | } | |
1809 | ira_setup_eliminable_regset (); | |
1810 | bitmap_initialize (&curr_regs_live, ®_obstack); | |
1811 | FOR_EACH_BB (bb) | |
1812 | { | |
1813 | curr_loop = bb->loop_father; | |
1814 | if (curr_loop == current_loops->tree_root) | |
1815 | continue; | |
1816 | ||
1817 | for (loop = curr_loop; | |
1818 | loop != current_loops->tree_root; | |
1819 | loop = loop_outer (loop)) | |
1820 | bitmap_ior_into (&LOOP_DATA (loop)->regs_live, DF_LR_IN (bb)); | |
1821 | ||
1822 | bitmap_copy (&curr_regs_live, DF_LR_IN (bb)); | |
66d9a7b9 | 1823 | for (i = 0; i < ira_pressure_classes_num; i++) |
1824 | curr_reg_pressure[ira_pressure_classes[i]] = 0; | |
e8eed2f8 | 1825 | EXECUTE_IF_SET_IN_BITMAP (&curr_regs_live, 0, j, bi) |
1826 | change_pressure (j, true); | |
1827 | ||
1828 | FOR_BB_INSNS (bb, insn) | |
1829 | { | |
c6a55b97 | 1830 | if (! NONDEBUG_INSN_P (insn)) |
e8eed2f8 | 1831 | continue; |
1832 | ||
1833 | mark_ref_regs (PATTERN (insn)); | |
1834 | n_regs_set = 0; | |
1835 | note_stores (PATTERN (insn), mark_reg_clobber, NULL); | |
48e1416a | 1836 | |
e8eed2f8 | 1837 | /* Mark any registers dead after INSN as dead now. */ |
48e1416a | 1838 | |
e8eed2f8 | 1839 | for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) |
1840 | if (REG_NOTE_KIND (link) == REG_DEAD) | |
1841 | mark_reg_death (XEXP (link, 0)); | |
48e1416a | 1842 | |
e8eed2f8 | 1843 | /* Mark any registers set in INSN as live, |
1844 | and mark them as conflicting with all other live regs. | |
1845 | Clobbers are processed again, so they conflict with | |
1846 | the registers that are set. */ | |
48e1416a | 1847 | |
e8eed2f8 | 1848 | note_stores (PATTERN (insn), mark_reg_store, NULL); |
48e1416a | 1849 | |
e8eed2f8 | 1850 | #ifdef AUTO_INC_DEC |
1851 | for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) | |
1852 | if (REG_NOTE_KIND (link) == REG_INC) | |
1853 | mark_reg_store (XEXP (link, 0), NULL_RTX, NULL); | |
1854 | #endif | |
1855 | while (n_regs_set-- > 0) | |
1856 | { | |
1857 | rtx note = find_regno_note (insn, REG_UNUSED, | |
1858 | REGNO (regs_set[n_regs_set])); | |
1859 | if (! note) | |
1860 | continue; | |
48e1416a | 1861 | |
e8eed2f8 | 1862 | mark_reg_death (XEXP (note, 0)); |
1863 | } | |
1864 | } | |
1865 | } | |
1866 | bitmap_clear (&curr_regs_live); | |
1867 | if (flag_ira_region == IRA_REGION_MIXED | |
1868 | || flag_ira_region == IRA_REGION_ALL) | |
1869 | FOR_EACH_LOOP (li, loop, 0) | |
1870 | { | |
1871 | EXECUTE_IF_SET_IN_BITMAP (&LOOP_DATA (loop)->regs_live, 0, j, bi) | |
1872 | if (! bitmap_bit_p (&LOOP_DATA (loop)->regs_ref, j)) | |
1873 | { | |
66d9a7b9 | 1874 | enum reg_class pressure_class; |
e8eed2f8 | 1875 | int nregs; |
1876 | ||
66d9a7b9 | 1877 | pressure_class = get_regno_pressure_class (j, &nregs); |
1878 | LOOP_DATA (loop)->max_reg_pressure[pressure_class] -= nregs; | |
e8eed2f8 | 1879 | } |
1880 | } | |
1881 | if (dump_file == NULL) | |
1882 | return; | |
1883 | FOR_EACH_LOOP (li, loop, 0) | |
1884 | { | |
1885 | parent = loop_outer (loop); | |
1886 | fprintf (dump_file, "\n Loop %d (parent %d, header bb%d, depth %d)\n", | |
1887 | loop->num, (parent == NULL ? -1 : parent->num), | |
1888 | loop->header->index, loop_depth (loop)); | |
1889 | fprintf (dump_file, "\n ref. regnos:"); | |
1890 | EXECUTE_IF_SET_IN_BITMAP (&LOOP_DATA (loop)->regs_ref, 0, j, bi) | |
1891 | fprintf (dump_file, " %d", j); | |
1892 | fprintf (dump_file, "\n live regnos:"); | |
1893 | EXECUTE_IF_SET_IN_BITMAP (&LOOP_DATA (loop)->regs_live, 0, j, bi) | |
1894 | fprintf (dump_file, " %d", j); | |
1895 | fprintf (dump_file, "\n Pressure:"); | |
66d9a7b9 | 1896 | for (i = 0; (int) i < ira_pressure_classes_num; i++) |
e8eed2f8 | 1897 | { |
66d9a7b9 | 1898 | enum reg_class pressure_class; |
48e1416a | 1899 | |
66d9a7b9 | 1900 | pressure_class = ira_pressure_classes[i]; |
1901 | if (LOOP_DATA (loop)->max_reg_pressure[pressure_class] == 0) | |
e8eed2f8 | 1902 | continue; |
66d9a7b9 | 1903 | fprintf (dump_file, " %s=%d", reg_class_names[pressure_class], |
1904 | LOOP_DATA (loop)->max_reg_pressure[pressure_class]); | |
e8eed2f8 | 1905 | } |
1906 | fprintf (dump_file, "\n"); | |
1907 | } | |
1908 | } | |
1909 | ||
1910 | \f | |
1911 | ||
7194de72 | 1912 | /* Move the invariants out of the loops. */ |
3a0ecac2 | 1913 | |
1914 | void | |
7194de72 | 1915 | move_loop_invariants (void) |
3a0ecac2 | 1916 | { |
1917 | struct loop *loop; | |
17519ba0 | 1918 | loop_iterator li; |
c2aa3ceb | 1919 | |
e8eed2f8 | 1920 | if (flag_ira_loop_pressure) |
1921 | { | |
1922 | df_analyze (); | |
66d9a7b9 | 1923 | regstat_init_n_sets_and_refs (); |
e8eed2f8 | 1924 | ira_set_pseudo_classes (dump_file); |
1925 | calculate_loop_reg_pressure (); | |
66d9a7b9 | 1926 | regstat_free_n_sets_and_refs (); |
e8eed2f8 | 1927 | } |
3072d30e | 1928 | df_set_flags (DF_EQ_NOTES + DF_DEFER_INSN_RESCAN); |
3a0ecac2 | 1929 | /* Process the loops, innermost first. */ |
17519ba0 | 1930 | FOR_EACH_LOOP (li, loop, LI_FROM_INNERMOST) |
3a0ecac2 | 1931 | { |
e8eed2f8 | 1932 | curr_loop = loop; |
86482d6b | 1933 | /* move_single_loop_invariants for very large loops |
1934 | is time consuming and might need a lot of memory. */ | |
1935 | if (loop->num_nodes <= (unsigned) LOOP_INVARIANT_MAX_BBS_IN_LOOP) | |
1936 | move_single_loop_invariants (loop); | |
3a0ecac2 | 1937 | } |
1938 | ||
17519ba0 | 1939 | FOR_EACH_LOOP (li, loop, 0) |
1940 | { | |
1941 | free_loop_data (loop); | |
1942 | } | |
3a0ecac2 | 1943 | |
e8eed2f8 | 1944 | if (flag_ira_loop_pressure) |
1945 | /* There is no sense to keep this info because it was most | |
1946 | probably outdated by subsequent passes. */ | |
1947 | free_reg_info (); | |
3072d30e | 1948 | free (invariant_table); |
1949 | invariant_table = NULL; | |
1950 | invariant_table_size = 0; | |
2c5cdc40 | 1951 | |
1952 | #ifdef ENABLE_CHECKING | |
1953 | verify_flow_info (); | |
1954 | #endif | |
3a0ecac2 | 1955 | } |