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c2aa3ceb | 1 | /* RTL-level loop invariant motion. |
fbd26352 | 2 | Copyright (C) 2004-2019 Free Software Foundation, Inc. |
c2aa3ceb | 3 | |
3a0ecac2 | 4 | This file is part of GCC. |
c2aa3ceb | 5 | |
3a0ecac2 | 6 | GCC is free software; you can redistribute it and/or modify it |
7 | under the terms of the GNU General Public License as published by the | |
8c4c00c1 | 8 | Free Software Foundation; either version 3, or (at your option) any |
3a0ecac2 | 9 | later version. |
c2aa3ceb | 10 | |
3a0ecac2 | 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. | |
c2aa3ceb | 15 | |
3a0ecac2 | 16 | You should have received a copy of the GNU General Public License |
8c4c00c1 | 17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
3a0ecac2 | 19 | |
20 | /* This implements the loop invariant motion pass. It is very simple | |
1e5b92fa | 21 | (no calls, no loads/stores, etc.). This should be sufficient to cleanup |
22 | things like address arithmetics -- other more complicated invariants should | |
23 | be eliminated on GIMPLE either in tree-ssa-loop-im.c or in tree-ssa-pre.c. | |
c2aa3ceb | 24 | |
3a0ecac2 | 25 | We proceed loop by loop -- it is simpler than trying to handle things |
26 | globally and should not lose much. First we inspect all sets inside loop | |
27 | and create a dependency graph on insns (saying "to move this insn, you must | |
28 | also move the following insns"). | |
29 | ||
30 | We then need to determine what to move. We estimate the number of registers | |
31 | used and move as many invariants as possible while we still have enough free | |
32 | registers. We prefer the expensive invariants. | |
c2aa3ceb | 33 | |
3a0ecac2 | 34 | Then we move the selected invariants out of the loop, creating a new |
35 | temporaries for them if necessary. */ | |
36 | ||
37 | #include "config.h" | |
38 | #include "system.h" | |
39 | #include "coretypes.h" | |
9ef16211 | 40 | #include "backend.h" |
7c29e30e | 41 | #include "target.h" |
3a0ecac2 | 42 | #include "rtl.h" |
7c29e30e | 43 | #include "tree.h" |
44 | #include "cfghooks.h" | |
9ef16211 | 45 | #include "df.h" |
ad7b10a2 | 46 | #include "memmodel.h" |
4a77dc8c | 47 | #include "tm_p.h" |
7c29e30e | 48 | #include "insn-config.h" |
49 | #include "regs.h" | |
50 | #include "ira.h" | |
51 | #include "recog.h" | |
94ea8568 | 52 | #include "cfgrtl.h" |
94ea8568 | 53 | #include "cfgloop.h" |
54 | #include "expr.h" | |
86482d6b | 55 | #include "params.h" |
51f6fdce | 56 | #include "rtl-iter.h" |
b9ed1410 | 57 | #include "dumpfile.h" |
3a0ecac2 | 58 | |
59 | /* The data stored for the loop. */ | |
60 | ||
251317e4 | 61 | class loop_data |
3a0ecac2 | 62 | { |
251317e4 | 63 | public: |
2e966e2a | 64 | class loop *outermost_exit; /* The outermost exit of the loop. */ |
3a0ecac2 | 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 | ||
2e966e2a | 74 | #define LOOP_DATA(LOOP) ((class loop_data *) (LOOP)->aux) |
3a0ecac2 | 75 | |
76 | /* The description of an use. */ | |
77 | ||
78 | struct use | |
79 | { | |
80 | rtx *pos; /* Position of the use. */ | |
ff395cd9 | 81 | rtx_insn *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. */ |
ee3ee950 | 95 | bool can_prop_to_addr_uses; /* True if the corresponding inv can be |
96 | propagated into its address uses. */ | |
3a0ecac2 | 97 | }; |
98 | ||
99 | /* The data stored for each invariant. */ | |
100 | ||
101 | struct invariant | |
102 | { | |
103 | /* The number of the invariant. */ | |
104 | unsigned invno; | |
105 | ||
3d6b8be7 | 106 | /* The number of the invariant with the same value. */ |
107 | unsigned eqto; | |
108 | ||
f69fbf74 | 109 | /* The number of invariants which eqto this. */ |
110 | unsigned eqno; | |
111 | ||
e8eed2f8 | 112 | /* If we moved the invariant out of the loop, the original regno |
113 | that contained its value. */ | |
114 | int orig_regno; | |
115 | ||
487798e2 | 116 | /* If we moved the invariant out of the loop, the register that contains its |
117 | value. */ | |
118 | rtx reg; | |
119 | ||
3a0ecac2 | 120 | /* The definition of the invariant. */ |
121 | struct def *def; | |
122 | ||
123 | /* The insn in that it is defined. */ | |
ff395cd9 | 124 | rtx_insn *insn; |
3a0ecac2 | 125 | |
126 | /* Whether it is always executed. */ | |
127 | bool always_executed; | |
128 | ||
129 | /* Whether to move the invariant. */ | |
130 | bool move; | |
131 | ||
68461c19 | 132 | /* Whether the invariant is cheap when used as an address. */ |
133 | bool cheap_address; | |
134 | ||
c2aa3ceb | 135 | /* Cost of the invariant. */ |
3a0ecac2 | 136 | unsigned cost; |
137 | ||
3a0ecac2 | 138 | /* Used for detecting already visited invariants during determining |
139 | costs of movements. */ | |
140 | unsigned stamp; | |
487798e2 | 141 | |
142 | /* The invariants it depends on. */ | |
143 | bitmap depends_on; | |
3a0ecac2 | 144 | }; |
145 | ||
e8eed2f8 | 146 | /* Currently processed loop. */ |
2e966e2a | 147 | static class loop *curr_loop; |
e8eed2f8 | 148 | |
3072d30e | 149 | /* Table of invariants indexed by the df_ref uid field. */ |
150 | ||
151 | static unsigned int invariant_table_size = 0; | |
152 | static struct invariant ** invariant_table; | |
153 | ||
3d6b8be7 | 154 | /* Entry for hash table of invariant expressions. */ |
155 | ||
156 | struct invariant_expr_entry | |
157 | { | |
158 | /* The invariant. */ | |
159 | struct invariant *inv; | |
160 | ||
161 | /* Its value. */ | |
162 | rtx expr; | |
163 | ||
164 | /* Its mode. */ | |
3754d046 | 165 | machine_mode mode; |
3d6b8be7 | 166 | |
167 | /* Its hash. */ | |
168 | hashval_t hash; | |
169 | }; | |
170 | ||
3a0ecac2 | 171 | /* The actual stamp for marking already visited invariants during determining |
172 | costs of movements. */ | |
173 | ||
174 | static unsigned actual_stamp; | |
175 | ||
703056c9 | 176 | typedef struct invariant *invariant_p; |
177 | ||
703056c9 | 178 | |
3a0ecac2 | 179 | /* The invariants. */ |
180 | ||
f1f41a6c | 181 | static vec<invariant_p> invariants; |
3a0ecac2 | 182 | |
3072d30e | 183 | /* Check the size of the invariant table and realloc if necessary. */ |
c2aa3ceb | 184 | |
48e1416a | 185 | static void |
3072d30e | 186 | check_invariant_table_size (void) |
187 | { | |
9af5ce0c | 188 | if (invariant_table_size < DF_DEFS_TABLE_SIZE ()) |
3072d30e | 189 | { |
190 | unsigned int new_size = DF_DEFS_TABLE_SIZE () + (DF_DEFS_TABLE_SIZE () / 4); | |
4077bf7a | 191 | invariant_table = XRESIZEVEC (struct invariant *, invariant_table, new_size); |
48e1416a | 192 | memset (&invariant_table[invariant_table_size], 0, |
9ddd9ef9 | 193 | (new_size - invariant_table_size) * sizeof (struct invariant *)); |
3072d30e | 194 | invariant_table_size = new_size; |
195 | } | |
196 | } | |
c2aa3ceb | 197 | |
3a0ecac2 | 198 | /* Test for possibility of invariantness of X. */ |
199 | ||
200 | static bool | |
201 | check_maybe_invariant (rtx x) | |
202 | { | |
203 | enum rtx_code code = GET_CODE (x); | |
204 | int i, j; | |
205 | const char *fmt; | |
206 | ||
207 | switch (code) | |
208 | { | |
0349edce | 209 | CASE_CONST_ANY: |
3a0ecac2 | 210 | case SYMBOL_REF: |
211 | case CONST: | |
212 | case LABEL_REF: | |
213 | return true; | |
214 | ||
215 | case PC: | |
216 | case CC0: | |
217 | case UNSPEC_VOLATILE: | |
218 | case CALL: | |
219 | return false; | |
220 | ||
221 | case REG: | |
222 | return true; | |
223 | ||
224 | case MEM: | |
225 | /* Load/store motion is done elsewhere. ??? Perhaps also add it here? | |
226 | It should not be hard, and might be faster than "elsewhere". */ | |
227 | ||
228 | /* Just handle the most trivial case where we load from an unchanging | |
229 | location (most importantly, pic tables). */ | |
13ecee21 | 230 | if (MEM_READONLY_P (x) && !MEM_VOLATILE_P (x)) |
3a0ecac2 | 231 | break; |
232 | ||
233 | return false; | |
234 | ||
235 | case ASM_OPERANDS: | |
236 | /* Don't mess with insns declared volatile. */ | |
237 | if (MEM_VOLATILE_P (x)) | |
238 | return false; | |
239 | break; | |
240 | ||
241 | default: | |
242 | break; | |
243 | } | |
244 | ||
245 | fmt = GET_RTX_FORMAT (code); | |
246 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
247 | { | |
248 | if (fmt[i] == 'e') | |
249 | { | |
250 | if (!check_maybe_invariant (XEXP (x, i))) | |
251 | return false; | |
252 | } | |
253 | else if (fmt[i] == 'E') | |
254 | { | |
255 | for (j = 0; j < XVECLEN (x, i); j++) | |
256 | if (!check_maybe_invariant (XVECEXP (x, i, j))) | |
257 | return false; | |
258 | } | |
259 | } | |
260 | ||
261 | return true; | |
262 | } | |
263 | ||
3d6b8be7 | 264 | /* Returns the invariant definition for USE, or NULL if USE is not |
265 | invariant. */ | |
266 | ||
267 | static struct invariant * | |
ed6e85ae | 268 | invariant_for_use (df_ref use) |
3d6b8be7 | 269 | { |
270 | struct df_link *defs; | |
ed6e85ae | 271 | df_ref def; |
158b6cc9 | 272 | basic_block bb = DF_REF_BB (use), def_bb; |
3d6b8be7 | 273 | |
ed6e85ae | 274 | if (DF_REF_FLAGS (use) & DF_REF_READ_WRITE) |
2e33cac5 | 275 | return NULL; |
276 | ||
3d6b8be7 | 277 | defs = DF_REF_CHAIN (use); |
278 | if (!defs || defs->next) | |
279 | return NULL; | |
280 | def = defs->ref; | |
3072d30e | 281 | check_invariant_table_size (); |
9af5ce0c | 282 | if (!invariant_table[DF_REF_ID (def)]) |
3d6b8be7 | 283 | return NULL; |
284 | ||
285 | def_bb = DF_REF_BB (def); | |
286 | if (!dominated_by_p (CDI_DOMINATORS, bb, def_bb)) | |
287 | return NULL; | |
9af5ce0c | 288 | return invariant_table[DF_REF_ID (def)]; |
3d6b8be7 | 289 | } |
290 | ||
291 | /* Computes hash value for invariant expression X in INSN. */ | |
292 | ||
293 | static hashval_t | |
ff395cd9 | 294 | hash_invariant_expr_1 (rtx_insn *insn, rtx x) |
3d6b8be7 | 295 | { |
296 | enum rtx_code code = GET_CODE (x); | |
297 | int i, j; | |
298 | const char *fmt; | |
299 | hashval_t val = code; | |
300 | int do_not_record_p; | |
ed6e85ae | 301 | df_ref use; |
3d6b8be7 | 302 | struct invariant *inv; |
303 | ||
304 | switch (code) | |
305 | { | |
0349edce | 306 | CASE_CONST_ANY: |
3d6b8be7 | 307 | case SYMBOL_REF: |
308 | case CONST: | |
309 | case LABEL_REF: | |
310 | return hash_rtx (x, GET_MODE (x), &do_not_record_p, NULL, false); | |
311 | ||
312 | case REG: | |
3072d30e | 313 | use = df_find_use (insn, x); |
3d6b8be7 | 314 | if (!use) |
315 | return hash_rtx (x, GET_MODE (x), &do_not_record_p, NULL, false); | |
316 | inv = invariant_for_use (use); | |
317 | if (!inv) | |
318 | return hash_rtx (x, GET_MODE (x), &do_not_record_p, NULL, false); | |
319 | ||
320 | gcc_assert (inv->eqto != ~0u); | |
321 | return inv->eqto; | |
322 | ||
323 | default: | |
324 | break; | |
325 | } | |
326 | ||
327 | fmt = GET_RTX_FORMAT (code); | |
328 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
329 | { | |
330 | if (fmt[i] == 'e') | |
331 | val ^= hash_invariant_expr_1 (insn, XEXP (x, i)); | |
332 | else if (fmt[i] == 'E') | |
333 | { | |
334 | for (j = 0; j < XVECLEN (x, i); j++) | |
335 | val ^= hash_invariant_expr_1 (insn, XVECEXP (x, i, j)); | |
336 | } | |
5df640f6 | 337 | else if (fmt[i] == 'i' || fmt[i] == 'n') |
338 | val ^= XINT (x, i); | |
9edf7ea8 | 339 | else if (fmt[i] == 'p') |
340 | val ^= constant_lower_bound (SUBREG_BYTE (x)); | |
3d6b8be7 | 341 | } |
342 | ||
343 | return val; | |
344 | } | |
345 | ||
346 | /* Returns true if the invariant expressions E1 and E2 used in insns INSN1 | |
347 | and INSN2 have always the same value. */ | |
348 | ||
349 | static bool | |
ff395cd9 | 350 | invariant_expr_equal_p (rtx_insn *insn1, rtx e1, rtx_insn *insn2, rtx e2) |
3d6b8be7 | 351 | { |
352 | enum rtx_code code = GET_CODE (e1); | |
353 | int i, j; | |
354 | const char *fmt; | |
ed6e85ae | 355 | df_ref use1, use2; |
3d6b8be7 | 356 | struct invariant *inv1 = NULL, *inv2 = NULL; |
357 | rtx sub1, sub2; | |
358 | ||
359 | /* If mode of only one of the operands is VOIDmode, it is not equivalent to | |
360 | the other one. If both are VOIDmode, we rely on the caller of this | |
361 | function to verify that their modes are the same. */ | |
362 | if (code != GET_CODE (e2) || GET_MODE (e1) != GET_MODE (e2)) | |
363 | return false; | |
364 | ||
365 | switch (code) | |
366 | { | |
0349edce | 367 | CASE_CONST_ANY: |
3d6b8be7 | 368 | case SYMBOL_REF: |
369 | case CONST: | |
370 | case LABEL_REF: | |
371 | return rtx_equal_p (e1, e2); | |
372 | ||
373 | case REG: | |
3072d30e | 374 | use1 = df_find_use (insn1, e1); |
375 | use2 = df_find_use (insn2, e2); | |
3d6b8be7 | 376 | if (use1) |
377 | inv1 = invariant_for_use (use1); | |
378 | if (use2) | |
379 | inv2 = invariant_for_use (use2); | |
380 | ||
381 | if (!inv1 && !inv2) | |
382 | return rtx_equal_p (e1, e2); | |
383 | ||
384 | if (!inv1 || !inv2) | |
385 | return false; | |
386 | ||
387 | gcc_assert (inv1->eqto != ~0u); | |
388 | gcc_assert (inv2->eqto != ~0u); | |
389 | return inv1->eqto == inv2->eqto; | |
390 | ||
391 | default: | |
392 | break; | |
393 | } | |
394 | ||
395 | fmt = GET_RTX_FORMAT (code); | |
396 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
397 | { | |
398 | if (fmt[i] == 'e') | |
399 | { | |
400 | sub1 = XEXP (e1, i); | |
401 | sub2 = XEXP (e2, i); | |
402 | ||
403 | if (!invariant_expr_equal_p (insn1, sub1, insn2, sub2)) | |
404 | return false; | |
405 | } | |
406 | ||
407 | else if (fmt[i] == 'E') | |
408 | { | |
409 | if (XVECLEN (e1, i) != XVECLEN (e2, i)) | |
410 | return false; | |
411 | ||
412 | for (j = 0; j < XVECLEN (e1, i); j++) | |
413 | { | |
414 | sub1 = XVECEXP (e1, i, j); | |
415 | sub2 = XVECEXP (e2, i, j); | |
416 | ||
417 | if (!invariant_expr_equal_p (insn1, sub1, insn2, sub2)) | |
418 | return false; | |
419 | } | |
420 | } | |
5df640f6 | 421 | else if (fmt[i] == 'i' || fmt[i] == 'n') |
422 | { | |
423 | if (XINT (e1, i) != XINT (e2, i)) | |
424 | return false; | |
425 | } | |
9edf7ea8 | 426 | else if (fmt[i] == 'p') |
427 | { | |
428 | if (maybe_ne (SUBREG_BYTE (e1), SUBREG_BYTE (e2))) | |
429 | return false; | |
430 | } | |
5df640f6 | 431 | /* Unhandled type of subexpression, we fail conservatively. */ |
432 | else | |
433 | return false; | |
3d6b8be7 | 434 | } |
435 | ||
436 | return true; | |
437 | } | |
438 | ||
298e7f9a | 439 | struct invariant_expr_hasher : free_ptr_hash <invariant_expr_entry> |
3d6b8be7 | 440 | { |
9969c043 | 441 | static inline hashval_t hash (const invariant_expr_entry *); |
442 | static inline bool equal (const invariant_expr_entry *, | |
443 | const invariant_expr_entry *); | |
d9dd21a8 | 444 | }; |
445 | ||
446 | /* Returns hash value for invariant expression entry ENTRY. */ | |
3d6b8be7 | 447 | |
d9dd21a8 | 448 | inline hashval_t |
9969c043 | 449 | invariant_expr_hasher::hash (const invariant_expr_entry *entry) |
d9dd21a8 | 450 | { |
3d6b8be7 | 451 | return entry->hash; |
452 | } | |
453 | ||
d9dd21a8 | 454 | /* Compares invariant expression entries ENTRY1 and ENTRY2. */ |
3d6b8be7 | 455 | |
d9dd21a8 | 456 | inline bool |
9969c043 | 457 | invariant_expr_hasher::equal (const invariant_expr_entry *entry1, |
458 | const invariant_expr_entry *entry2) | |
3d6b8be7 | 459 | { |
3d6b8be7 | 460 | if (entry1->mode != entry2->mode) |
461 | return 0; | |
462 | ||
463 | return invariant_expr_equal_p (entry1->inv->insn, entry1->expr, | |
464 | entry2->inv->insn, entry2->expr); | |
465 | } | |
466 | ||
c1f445d2 | 467 | typedef hash_table<invariant_expr_hasher> invariant_htab_type; |
d9dd21a8 | 468 | |
3d6b8be7 | 469 | /* Checks whether invariant with value EXPR in machine mode MODE is |
470 | recorded in EQ. If this is the case, return the invariant. Otherwise | |
471 | insert INV to the table for this expression and return INV. */ | |
472 | ||
473 | static struct invariant * | |
3754d046 | 474 | find_or_insert_inv (invariant_htab_type *eq, rtx expr, machine_mode mode, |
3d6b8be7 | 475 | struct invariant *inv) |
476 | { | |
477 | hashval_t hash = hash_invariant_expr_1 (inv->insn, expr); | |
478 | struct invariant_expr_entry *entry; | |
479 | struct invariant_expr_entry pentry; | |
d9dd21a8 | 480 | invariant_expr_entry **slot; |
3d6b8be7 | 481 | |
482 | pentry.expr = expr; | |
483 | pentry.inv = inv; | |
484 | pentry.mode = mode; | |
c1f445d2 | 485 | slot = eq->find_slot_with_hash (&pentry, hash, INSERT); |
d9dd21a8 | 486 | entry = *slot; |
3d6b8be7 | 487 | |
488 | if (entry) | |
489 | return entry->inv; | |
490 | ||
4c36ffe6 | 491 | entry = XNEW (struct invariant_expr_entry); |
3d6b8be7 | 492 | entry->inv = inv; |
493 | entry->expr = expr; | |
494 | entry->mode = mode; | |
495 | entry->hash = hash; | |
496 | *slot = entry; | |
497 | ||
498 | return inv; | |
499 | } | |
500 | ||
501 | /* Finds invariants identical to INV and records the equivalence. EQ is the | |
502 | hash table of the invariants. */ | |
503 | ||
504 | static void | |
c1f445d2 | 505 | find_identical_invariants (invariant_htab_type *eq, struct invariant *inv) |
3d6b8be7 | 506 | { |
507 | unsigned depno; | |
508 | bitmap_iterator bi; | |
509 | struct invariant *dep; | |
510 | rtx expr, set; | |
3754d046 | 511 | machine_mode mode; |
f69fbf74 | 512 | struct invariant *tmp; |
3d6b8be7 | 513 | |
514 | if (inv->eqto != ~0u) | |
515 | return; | |
516 | ||
517 | EXECUTE_IF_SET_IN_BITMAP (inv->depends_on, 0, depno, bi) | |
518 | { | |
f1f41a6c | 519 | dep = invariants[depno]; |
3d6b8be7 | 520 | find_identical_invariants (eq, dep); |
521 | } | |
522 | ||
523 | set = single_set (inv->insn); | |
524 | expr = SET_SRC (set); | |
525 | mode = GET_MODE (expr); | |
526 | if (mode == VOIDmode) | |
527 | mode = GET_MODE (SET_DEST (set)); | |
f69fbf74 | 528 | |
529 | tmp = find_or_insert_inv (eq, expr, mode, inv); | |
530 | inv->eqto = tmp->invno; | |
531 | ||
532 | if (tmp->invno != inv->invno && inv->always_executed) | |
533 | tmp->eqno++; | |
3d6b8be7 | 534 | |
535 | if (dump_file && inv->eqto != inv->invno) | |
536 | fprintf (dump_file, | |
5ed26a34 | 537 | "Invariant %d is equivalent to invariant %d.\n", |
3d6b8be7 | 538 | inv->invno, inv->eqto); |
539 | } | |
540 | ||
541 | /* Find invariants with the same value and record the equivalences. */ | |
542 | ||
543 | static void | |
544 | merge_identical_invariants (void) | |
545 | { | |
546 | unsigned i; | |
547 | struct invariant *inv; | |
c1f445d2 | 548 | invariant_htab_type eq (invariants.length ()); |
3d6b8be7 | 549 | |
f1f41a6c | 550 | FOR_EACH_VEC_ELT (invariants, i, inv) |
c1f445d2 | 551 | find_identical_invariants (&eq, inv); |
3d6b8be7 | 552 | } |
553 | ||
3a0ecac2 | 554 | /* Determines the basic blocks inside LOOP that are always executed and |
555 | stores their bitmap to ALWAYS_REACHED. MAY_EXIT is a bitmap of | |
556 | basic blocks that may either exit the loop, or contain the call that | |
557 | does not have to return. BODY is body of the loop obtained by | |
558 | get_loop_body_in_dom_order. */ | |
559 | ||
560 | static void | |
2e966e2a | 561 | compute_always_reached (class loop *loop, basic_block *body, |
3a0ecac2 | 562 | bitmap may_exit, bitmap always_reached) |
563 | { | |
564 | unsigned i; | |
565 | ||
566 | for (i = 0; i < loop->num_nodes; i++) | |
567 | { | |
568 | if (dominated_by_p (CDI_DOMINATORS, loop->latch, body[i])) | |
569 | bitmap_set_bit (always_reached, i); | |
570 | ||
571 | if (bitmap_bit_p (may_exit, i)) | |
572 | return; | |
573 | } | |
574 | } | |
575 | ||
576 | /* Finds exits out of the LOOP with body BODY. Marks blocks in that we may | |
577 | exit the loop by cfg edge to HAS_EXIT and MAY_EXIT. In MAY_EXIT | |
578 | additionally mark blocks that may exit due to a call. */ | |
579 | ||
580 | static void | |
2e966e2a | 581 | find_exits (class loop *loop, basic_block *body, |
3a0ecac2 | 582 | bitmap may_exit, bitmap has_exit) |
583 | { | |
584 | unsigned i; | |
cd665a06 | 585 | edge_iterator ei; |
3a0ecac2 | 586 | edge e; |
2e966e2a | 587 | class loop *outermost_exit = loop, *aexit; |
3a0ecac2 | 588 | bool has_call = false; |
ff395cd9 | 589 | rtx_insn *insn; |
3a0ecac2 | 590 | |
591 | for (i = 0; i < loop->num_nodes; i++) | |
592 | { | |
593 | if (body[i]->loop_father == loop) | |
594 | { | |
595 | FOR_BB_INSNS (body[i], insn) | |
596 | { | |
6d7dc5b9 | 597 | if (CALL_P (insn) |
9c2a0c05 | 598 | && (RTL_LOOPING_CONST_OR_PURE_CALL_P (insn) |
599 | || !RTL_CONST_OR_PURE_CALL_P (insn))) | |
3a0ecac2 | 600 | { |
601 | has_call = true; | |
602 | bitmap_set_bit (may_exit, i); | |
603 | break; | |
604 | } | |
605 | } | |
606 | ||
cd665a06 | 607 | FOR_EACH_EDGE (e, ei, body[i]->succs) |
3a0ecac2 | 608 | { |
5b9b62c9 | 609 | if (! flow_bb_inside_loop_p (loop, e->dest)) |
610 | { | |
611 | bitmap_set_bit (may_exit, i); | |
612 | bitmap_set_bit (has_exit, i); | |
613 | outermost_exit = find_common_loop (outermost_exit, | |
614 | e->dest->loop_father); | |
615 | } | |
616 | /* If we enter a subloop that might never terminate treat | |
617 | it like a possible exit. */ | |
618 | if (flow_loop_nested_p (loop, e->dest->loop_father)) | |
619 | bitmap_set_bit (may_exit, i); | |
3a0ecac2 | 620 | } |
621 | continue; | |
622 | } | |
c2aa3ceb | 623 | |
3a0ecac2 | 624 | /* Use the data stored for the subloop to decide whether we may exit |
625 | through it. It is sufficient to do this for header of the loop, | |
626 | as other basic blocks inside it must be dominated by it. */ | |
627 | if (body[i]->loop_father->header != body[i]) | |
628 | continue; | |
629 | ||
630 | if (LOOP_DATA (body[i]->loop_father)->has_call) | |
631 | { | |
632 | has_call = true; | |
633 | bitmap_set_bit (may_exit, i); | |
634 | } | |
635 | aexit = LOOP_DATA (body[i]->loop_father)->outermost_exit; | |
636 | if (aexit != loop) | |
637 | { | |
638 | bitmap_set_bit (may_exit, i); | |
639 | bitmap_set_bit (has_exit, i); | |
640 | ||
641 | if (flow_loop_nested_p (aexit, outermost_exit)) | |
642 | outermost_exit = aexit; | |
643 | } | |
644 | } | |
645 | ||
e8eed2f8 | 646 | if (loop->aux == NULL) |
647 | { | |
2e966e2a | 648 | loop->aux = xcalloc (1, sizeof (class loop_data)); |
e8eed2f8 | 649 | bitmap_initialize (&LOOP_DATA (loop)->regs_ref, ®_obstack); |
650 | bitmap_initialize (&LOOP_DATA (loop)->regs_live, ®_obstack); | |
651 | } | |
3a0ecac2 | 652 | LOOP_DATA (loop)->outermost_exit = outermost_exit; |
653 | LOOP_DATA (loop)->has_call = has_call; | |
654 | } | |
655 | ||
656 | /* Check whether we may assign a value to X from a register. */ | |
657 | ||
658 | static bool | |
659 | may_assign_reg_p (rtx x) | |
660 | { | |
51fb5608 | 661 | return (GET_MODE (x) != VOIDmode |
a436996a | 662 | && GET_MODE (x) != BLKmode |
51fb5608 | 663 | && can_copy_p (GET_MODE (x)) |
88636fce | 664 | /* Do not mess with the frame pointer adjustments that can |
665 | be generated e.g. by expand_builtin_setjmp_receiver. */ | |
666 | && x != frame_pointer_rtx | |
2c5cdc40 | 667 | && (!REG_P (x) |
668 | || !HARD_REGISTER_P (x) | |
669 | || REGNO_REG_CLASS (REGNO (x)) != NO_REGS)); | |
3a0ecac2 | 670 | } |
671 | ||
c2aa3ceb | 672 | /* Finds definitions that may correspond to invariants in LOOP with body |
673 | BODY. */ | |
3a0ecac2 | 674 | |
675 | static void | |
2e966e2a | 676 | find_defs (class loop *loop) |
3a0ecac2 | 677 | { |
ea9538fb | 678 | if (dump_file) |
679 | { | |
680 | fprintf (dump_file, | |
681 | "*****starting processing of loop %d ******\n", | |
682 | loop->num); | |
683 | } | |
684 | ||
3072d30e | 685 | df_chain_add_problem (DF_UD_CHAIN); |
ea9538fb | 686 | df_set_flags (DF_RD_PRUNE_DEAD_DEFS); |
67e23d6f | 687 | df_analyze_loop (loop); |
ea9538fb | 688 | check_invariant_table_size (); |
3072d30e | 689 | |
690 | if (dump_file) | |
691 | { | |
774f8797 | 692 | df_dump_region (dump_file); |
ea9538fb | 693 | fprintf (dump_file, |
694 | "*****ending processing of loop %d ******\n", | |
695 | loop->num); | |
3072d30e | 696 | } |
3a0ecac2 | 697 | } |
698 | ||
699 | /* Creates a new invariant for definition DEF in INSN, depending on invariants | |
700 | in DEPENDS_ON. ALWAYS_EXECUTED is true if the insn is always executed, | |
3d6b8be7 | 701 | unless the program ends due to a function call. The newly created invariant |
702 | is returned. */ | |
3a0ecac2 | 703 | |
3d6b8be7 | 704 | static struct invariant * |
ff395cd9 | 705 | create_new_invariant (struct def *def, rtx_insn *insn, bitmap depends_on, |
3a0ecac2 | 706 | bool always_executed) |
707 | { | |
4c36ffe6 | 708 | struct invariant *inv = XNEW (struct invariant); |
3a0ecac2 | 709 | rtx set = single_set (insn); |
f529eb25 | 710 | bool speed = optimize_bb_for_speed_p (BLOCK_FOR_INSN (insn)); |
3a0ecac2 | 711 | |
712 | inv->def = def; | |
713 | inv->always_executed = always_executed; | |
714 | inv->depends_on = depends_on; | |
715 | ||
716 | /* If the set is simple, usually by moving it we move the whole store out of | |
717 | the loop. Otherwise we save only cost of the computation. */ | |
718 | if (def) | |
68461c19 | 719 | { |
b72d459f | 720 | inv->cost = set_rtx_cost (set, speed); |
21a9b734 | 721 | /* ??? Try to determine cheapness of address computation. Unfortunately |
722 | the address cost is only a relative measure, we can't really compare | |
723 | it with any absolute number, but only with other address costs. | |
724 | But here we don't have any other addresses, so compare with a magic | |
725 | number anyway. It has to be large enough to not regress PR33928 | |
726 | (by avoiding to move reg+8,reg+16,reg+24 invariants), but small | |
727 | enough to not regress 410.bwaves either (by still moving reg+reg | |
728 | invariants). | |
729 | See http://gcc.gnu.org/ml/gcc-patches/2009-10/msg01210.html . */ | |
09c7ce53 | 730 | if (SCALAR_INT_MODE_P (GET_MODE (SET_DEST (set)))) |
731 | inv->cheap_address = address_cost (SET_SRC (set), word_mode, | |
732 | ADDR_SPACE_GENERIC, speed) < 3; | |
733 | else | |
734 | inv->cheap_address = false; | |
68461c19 | 735 | } |
3a0ecac2 | 736 | else |
68461c19 | 737 | { |
5ae4887d | 738 | inv->cost = set_src_cost (SET_SRC (set), GET_MODE (SET_DEST (set)), |
739 | speed); | |
68461c19 | 740 | inv->cheap_address = false; |
741 | } | |
3a0ecac2 | 742 | |
743 | inv->move = false; | |
3d6b8be7 | 744 | inv->reg = NULL_RTX; |
e8eed2f8 | 745 | inv->orig_regno = -1; |
3a0ecac2 | 746 | inv->stamp = 0; |
747 | inv->insn = insn; | |
748 | ||
f1f41a6c | 749 | inv->invno = invariants.length (); |
3d6b8be7 | 750 | inv->eqto = ~0u; |
f69fbf74 | 751 | |
752 | /* Itself. */ | |
753 | inv->eqno = 1; | |
754 | ||
3a0ecac2 | 755 | if (def) |
756 | def->invno = inv->invno; | |
f1f41a6c | 757 | invariants.safe_push (inv); |
3a0ecac2 | 758 | |
759 | if (dump_file) | |
760 | { | |
761 | fprintf (dump_file, | |
762 | "Set in insn %d is invariant (%d), cost %d, depends on ", | |
763 | INSN_UID (insn), inv->invno, inv->cost); | |
764 | dump_bitmap (dump_file, inv->depends_on); | |
765 | } | |
3d6b8be7 | 766 | |
767 | return inv; | |
3a0ecac2 | 768 | } |
769 | ||
51f6fdce | 770 | /* Return a canonical version of X for the address, from the point of view, |
771 | that all multiplications are represented as MULT instead of the multiply | |
772 | by a power of 2 being represented as ASHIFT. | |
773 | ||
774 | Callers should prepare a copy of X because this function may modify it | |
775 | in place. */ | |
776 | ||
777 | static void | |
778 | canonicalize_address_mult (rtx x) | |
779 | { | |
780 | subrtx_var_iterator::array_type array; | |
781 | FOR_EACH_SUBRTX_VAR (iter, array, x, NONCONST) | |
782 | { | |
783 | rtx sub = *iter; | |
5c7e74d4 | 784 | scalar_int_mode sub_mode; |
785 | if (is_a <scalar_int_mode> (GET_MODE (sub), &sub_mode) | |
786 | && GET_CODE (sub) == ASHIFT | |
51f6fdce | 787 | && CONST_INT_P (XEXP (sub, 1)) |
5c7e74d4 | 788 | && INTVAL (XEXP (sub, 1)) < GET_MODE_BITSIZE (sub_mode) |
51f6fdce | 789 | && INTVAL (XEXP (sub, 1)) >= 0) |
790 | { | |
791 | HOST_WIDE_INT shift = INTVAL (XEXP (sub, 1)); | |
792 | PUT_CODE (sub, MULT); | |
5c7e74d4 | 793 | XEXP (sub, 1) = gen_int_mode (HOST_WIDE_INT_1 << shift, sub_mode); |
51f6fdce | 794 | iter.skip_subrtxes (); |
795 | } | |
796 | } | |
797 | } | |
798 | ||
799 | /* Maximum number of sub expressions in address. We set it to | |
800 | a small integer since it's unlikely to have a complicated | |
801 | address expression. */ | |
802 | ||
803 | #define MAX_CANON_ADDR_PARTS (5) | |
804 | ||
805 | /* Collect sub expressions in address X with PLUS as the seperator. | |
806 | Sub expressions are stored in vector ADDR_PARTS. */ | |
807 | ||
808 | static void | |
809 | collect_address_parts (rtx x, vec<rtx> *addr_parts) | |
810 | { | |
811 | subrtx_var_iterator::array_type array; | |
812 | FOR_EACH_SUBRTX_VAR (iter, array, x, NONCONST) | |
813 | { | |
814 | rtx sub = *iter; | |
815 | ||
816 | if (GET_CODE (sub) != PLUS) | |
817 | { | |
818 | addr_parts->safe_push (sub); | |
819 | iter.skip_subrtxes (); | |
820 | } | |
821 | } | |
822 | } | |
823 | ||
824 | /* Compare function for sorting sub expressions X and Y based on | |
825 | precedence defined for communitive operations. */ | |
826 | ||
827 | static int | |
828 | compare_address_parts (const void *x, const void *y) | |
829 | { | |
830 | const rtx *rx = (const rtx *)x; | |
831 | const rtx *ry = (const rtx *)y; | |
832 | int px = commutative_operand_precedence (*rx); | |
833 | int py = commutative_operand_precedence (*ry); | |
834 | ||
835 | return (py - px); | |
836 | } | |
837 | ||
838 | /* Return a canonical version address for X by following steps: | |
839 | 1) Rewrite ASHIFT into MULT recursively. | |
840 | 2) Divide address into sub expressions with PLUS as the | |
841 | separator. | |
842 | 3) Sort sub expressions according to precedence defined | |
843 | for communative operations. | |
844 | 4) Simplify CONST_INT_P sub expressions. | |
845 | 5) Create new canonicalized address and return. | |
846 | Callers should prepare a copy of X because this function may | |
847 | modify it in place. */ | |
848 | ||
849 | static rtx | |
850 | canonicalize_address (rtx x) | |
851 | { | |
852 | rtx res; | |
853 | unsigned int i, j; | |
854 | machine_mode mode = GET_MODE (x); | |
855 | auto_vec<rtx, MAX_CANON_ADDR_PARTS> addr_parts; | |
856 | ||
857 | /* Rewrite ASHIFT into MULT. */ | |
858 | canonicalize_address_mult (x); | |
859 | /* Divide address into sub expressions. */ | |
860 | collect_address_parts (x, &addr_parts); | |
861 | /* Unlikely to have very complicated address. */ | |
862 | if (addr_parts.length () < 2 | |
863 | || addr_parts.length () > MAX_CANON_ADDR_PARTS) | |
864 | return x; | |
865 | ||
866 | /* Sort sub expressions according to canonicalization precedence. */ | |
867 | addr_parts.qsort (compare_address_parts); | |
868 | ||
869 | /* Simplify all constant int summary if possible. */ | |
870 | for (i = 0; i < addr_parts.length (); i++) | |
871 | if (CONST_INT_P (addr_parts[i])) | |
872 | break; | |
873 | ||
874 | for (j = i + 1; j < addr_parts.length (); j++) | |
875 | { | |
876 | gcc_assert (CONST_INT_P (addr_parts[j])); | |
877 | addr_parts[i] = simplify_gen_binary (PLUS, mode, | |
878 | addr_parts[i], | |
879 | addr_parts[j]); | |
880 | } | |
881 | ||
882 | /* Chain PLUS operators to the left for !CONST_INT_P sub expressions. */ | |
883 | res = addr_parts[0]; | |
884 | for (j = 1; j < i; j++) | |
885 | res = simplify_gen_binary (PLUS, mode, res, addr_parts[j]); | |
886 | ||
887 | /* Pickup the last CONST_INT_P sub expression. */ | |
888 | if (i < addr_parts.length ()) | |
889 | res = simplify_gen_binary (PLUS, mode, res, addr_parts[i]); | |
890 | ||
891 | return res; | |
892 | } | |
893 | ||
ee3ee950 | 894 | /* Given invariant DEF and its address USE, check if the corresponding |
895 | invariant expr can be propagated into the use or not. */ | |
896 | ||
897 | static bool | |
898 | inv_can_prop_to_addr_use (struct def *def, df_ref use) | |
899 | { | |
900 | struct invariant *inv; | |
51f6fdce | 901 | rtx *pos = DF_REF_REAL_LOC (use), def_set, use_set; |
ee3ee950 | 902 | rtx_insn *use_insn = DF_REF_INSN (use); |
903 | rtx_insn *def_insn; | |
904 | bool ok; | |
905 | ||
906 | inv = invariants[def->invno]; | |
907 | /* No need to check if address expression is expensive. */ | |
908 | if (!inv->cheap_address) | |
909 | return false; | |
910 | ||
911 | def_insn = inv->insn; | |
912 | def_set = single_set (def_insn); | |
913 | if (!def_set) | |
914 | return false; | |
915 | ||
916 | validate_unshare_change (use_insn, pos, SET_SRC (def_set), true); | |
917 | ok = verify_changes (0); | |
51f6fdce | 918 | /* Try harder with canonicalization in address expression. */ |
919 | if (!ok && (use_set = single_set (use_insn)) != NULL_RTX) | |
920 | { | |
921 | rtx src, dest, mem = NULL_RTX; | |
922 | ||
923 | src = SET_SRC (use_set); | |
924 | dest = SET_DEST (use_set); | |
925 | if (MEM_P (src)) | |
926 | mem = src; | |
927 | else if (MEM_P (dest)) | |
928 | mem = dest; | |
929 | ||
930 | if (mem != NULL_RTX | |
931 | && !memory_address_addr_space_p (GET_MODE (mem), | |
932 | XEXP (mem, 0), | |
933 | MEM_ADDR_SPACE (mem))) | |
934 | { | |
935 | rtx addr = canonicalize_address (copy_rtx (XEXP (mem, 0))); | |
936 | if (memory_address_addr_space_p (GET_MODE (mem), | |
937 | addr, MEM_ADDR_SPACE (mem))) | |
938 | ok = true; | |
939 | } | |
940 | } | |
ee3ee950 | 941 | cancel_changes (0); |
942 | return ok; | |
943 | } | |
944 | ||
3a0ecac2 | 945 | /* Record USE at DEF. */ |
946 | ||
947 | static void | |
68461c19 | 948 | record_use (struct def *def, df_ref use) |
3a0ecac2 | 949 | { |
4c36ffe6 | 950 | struct use *u = XNEW (struct use); |
3a0ecac2 | 951 | |
68461c19 | 952 | u->pos = DF_REF_REAL_LOC (use); |
953 | u->insn = DF_REF_INSN (use); | |
954 | u->addr_use_p = (DF_REF_TYPE (use) == DF_REF_REG_MEM_LOAD | |
5c83cd34 | 955 | || DF_REF_TYPE (use) == DF_REF_REG_MEM_STORE); |
3a0ecac2 | 956 | u->next = def->uses; |
957 | def->uses = u; | |
958 | def->n_uses++; | |
68461c19 | 959 | if (u->addr_use_p) |
ee3ee950 | 960 | { |
961 | /* Initialize propagation information if this is the first addr | |
962 | use of the inv def. */ | |
963 | if (def->n_addr_uses == 0) | |
964 | def->can_prop_to_addr_uses = true; | |
965 | ||
966 | def->n_addr_uses++; | |
967 | if (def->can_prop_to_addr_uses && !inv_can_prop_to_addr_use (def, use)) | |
968 | def->can_prop_to_addr_uses = false; | |
969 | } | |
3a0ecac2 | 970 | } |
971 | ||
3072d30e | 972 | /* Finds the invariants USE depends on and store them to the DEPENDS_ON |
973 | bitmap. Returns true if all dependencies of USE are known to be | |
2e33cac5 | 974 | loop invariants, false otherwise. */ |
3a0ecac2 | 975 | |
976 | static bool | |
ed6e85ae | 977 | check_dependency (basic_block bb, df_ref use, bitmap depends_on) |
3a0ecac2 | 978 | { |
ed6e85ae | 979 | df_ref def; |
3072d30e | 980 | basic_block def_bb; |
e011eba9 | 981 | struct df_link *defs; |
3a0ecac2 | 982 | struct def *def_data; |
3d6b8be7 | 983 | struct invariant *inv; |
48e1416a | 984 | |
ed6e85ae | 985 | if (DF_REF_FLAGS (use) & DF_REF_READ_WRITE) |
3072d30e | 986 | return false; |
48e1416a | 987 | |
3072d30e | 988 | defs = DF_REF_CHAIN (use); |
989 | if (!defs) | |
520a90d9 | 990 | { |
991 | unsigned int regno = DF_REF_REGNO (use); | |
992 | ||
993 | /* If this is the use of an uninitialized argument register that is | |
994 | likely to be spilled, do not move it lest this might extend its | |
995 | lifetime and cause reload to die. This can occur for a call to | |
996 | a function taking complex number arguments and moving the insns | |
997 | preparing the arguments without moving the call itself wouldn't | |
998 | gain much in practice. */ | |
999 | if ((DF_REF_FLAGS (use) & DF_HARD_REG_LIVE) | |
1000 | && FUNCTION_ARG_REGNO_P (regno) | |
1001 | && targetm.class_likely_spilled_p (REGNO_REG_CLASS (regno))) | |
1002 | return false; | |
1003 | ||
1004 | return true; | |
1005 | } | |
48e1416a | 1006 | |
3072d30e | 1007 | if (defs->next) |
1008 | return false; | |
48e1416a | 1009 | |
3072d30e | 1010 | def = defs->ref; |
1011 | check_invariant_table_size (); | |
9af5ce0c | 1012 | inv = invariant_table[DF_REF_ID (def)]; |
3072d30e | 1013 | if (!inv) |
1014 | return false; | |
48e1416a | 1015 | |
3072d30e | 1016 | def_data = inv->def; |
1017 | gcc_assert (def_data != NULL); | |
48e1416a | 1018 | |
3072d30e | 1019 | def_bb = DF_REF_BB (def); |
1020 | /* Note that in case bb == def_bb, we know that the definition | |
1021 | dominates insn, because def has invariant_table[DF_REF_ID(def)] | |
1022 | defined and we process the insns in the basic block bb | |
1023 | sequentially. */ | |
1024 | if (!dominated_by_p (CDI_DOMINATORS, bb, def_bb)) | |
1025 | return false; | |
48e1416a | 1026 | |
3072d30e | 1027 | bitmap_set_bit (depends_on, def_data->invno); |
1028 | return true; | |
1029 | } | |
3d6b8be7 | 1030 | |
3d6b8be7 | 1031 | |
3072d30e | 1032 | /* Finds the invariants INSN depends on and store them to the DEPENDS_ON |
1033 | bitmap. Returns true if all dependencies of INSN are known to be | |
1034 | loop invariants, false otherwise. */ | |
3a0ecac2 | 1035 | |
3072d30e | 1036 | static bool |
ff395cd9 | 1037 | check_dependencies (rtx_insn *insn, bitmap depends_on) |
3072d30e | 1038 | { |
158b6cc9 | 1039 | struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn); |
be10bb5a | 1040 | df_ref use; |
3072d30e | 1041 | basic_block bb = BLOCK_FOR_INSN (insn); |
3a0ecac2 | 1042 | |
be10bb5a | 1043 | FOR_EACH_INSN_INFO_USE (use, insn_info) |
1044 | if (!check_dependency (bb, use, depends_on)) | |
3072d30e | 1045 | return false; |
be10bb5a | 1046 | FOR_EACH_INSN_INFO_EQ_USE (use, insn_info) |
1047 | if (!check_dependency (bb, use, depends_on)) | |
3072d30e | 1048 | return false; |
48e1416a | 1049 | |
3a0ecac2 | 1050 | return true; |
1051 | } | |
1052 | ||
f4d3c071 | 1053 | /* Pre-check candidate DEST to skip the one which cannot make a valid insn |
9b59e217 | 1054 | during move_invariant_reg. SIMPLE is to skip HARD_REGISTER. */ |
1055 | static bool | |
1056 | pre_check_invariant_p (bool simple, rtx dest) | |
1057 | { | |
1058 | if (simple && REG_P (dest) && DF_REG_DEF_COUNT (REGNO (dest)) > 1) | |
1059 | { | |
1060 | df_ref use; | |
9b59e217 | 1061 | unsigned int i = REGNO (dest); |
1062 | struct df_insn_info *insn_info; | |
1063 | df_ref def_rec; | |
1064 | ||
1065 | for (use = DF_REG_USE_CHAIN (i); use; use = DF_REF_NEXT_REG (use)) | |
1066 | { | |
9ed997be | 1067 | rtx_insn *ref = DF_REF_INSN (use); |
9b59e217 | 1068 | insn_info = DF_INSN_INFO_GET (ref); |
1069 | ||
1070 | FOR_EACH_INSN_INFO_DEF (def_rec, insn_info) | |
1071 | if (DF_REF_REGNO (def_rec) == i) | |
1072 | { | |
1073 | /* Multi definitions at this stage, most likely are due to | |
1074 | instruction constraints, which requires both read and write | |
1075 | on the same register. Since move_invariant_reg is not | |
1076 | powerful enough to handle such cases, just ignore the INV | |
1077 | and leave the chance to others. */ | |
1078 | return false; | |
1079 | } | |
1080 | } | |
1081 | } | |
1082 | return true; | |
1083 | } | |
1084 | ||
3a0ecac2 | 1085 | /* Finds invariant in INSN. ALWAYS_REACHED is true if the insn is always |
1086 | executed. ALWAYS_EXECUTED is true if the insn is always executed, | |
c2aa3ceb | 1087 | unless the program ends due to a function call. */ |
3a0ecac2 | 1088 | |
1089 | static void | |
ff395cd9 | 1090 | find_invariant_insn (rtx_insn *insn, bool always_reached, bool always_executed) |
3a0ecac2 | 1091 | { |
ed6e85ae | 1092 | df_ref ref; |
3a0ecac2 | 1093 | struct def *def; |
1094 | bitmap depends_on; | |
1095 | rtx set, dest; | |
1096 | bool simple = true; | |
3d6b8be7 | 1097 | struct invariant *inv; |
3a0ecac2 | 1098 | |
d9da8b4c | 1099 | /* We can't move a CC0 setter without the user. */ |
ff900b8e | 1100 | if (HAVE_cc0 && sets_cc0_p (insn)) |
d9da8b4c | 1101 | return; |
d9da8b4c | 1102 | |
3a0ecac2 | 1103 | set = single_set (insn); |
1104 | if (!set) | |
1105 | return; | |
1106 | dest = SET_DEST (set); | |
1107 | ||
1c14a50e | 1108 | if (!REG_P (dest) |
3a0ecac2 | 1109 | || HARD_REGISTER_P (dest)) |
1110 | simple = false; | |
1111 | ||
9b59e217 | 1112 | if (!may_assign_reg_p (dest) |
1113 | || !pre_check_invariant_p (simple, dest) | |
2c5cdc40 | 1114 | || !check_maybe_invariant (SET_SRC (set))) |
3a0ecac2 | 1115 | return; |
1116 | ||
a39b96b6 | 1117 | /* If the insn can throw exception, we cannot move it at all without changing |
1118 | cfg. */ | |
1119 | if (can_throw_internal (insn)) | |
1120 | return; | |
3a0ecac2 | 1121 | |
a39b96b6 | 1122 | /* We cannot make trapping insn executed, unless it was executed before. */ |
0eee494e | 1123 | if (may_trap_or_fault_p (PATTERN (insn)) && !always_reached) |
a39b96b6 | 1124 | return; |
3a0ecac2 | 1125 | |
27335ffd | 1126 | depends_on = BITMAP_ALLOC (NULL); |
c2aa3ceb | 1127 | if (!check_dependencies (insn, depends_on)) |
3a0ecac2 | 1128 | { |
27335ffd | 1129 | BITMAP_FREE (depends_on); |
3a0ecac2 | 1130 | return; |
1131 | } | |
1132 | ||
1133 | if (simple) | |
4c36ffe6 | 1134 | def = XCNEW (struct def); |
3a0ecac2 | 1135 | else |
1136 | def = NULL; | |
1137 | ||
3d6b8be7 | 1138 | inv = create_new_invariant (def, insn, depends_on, always_executed); |
1139 | ||
1140 | if (simple) | |
1141 | { | |
3072d30e | 1142 | ref = df_find_def (insn, dest); |
1143 | check_invariant_table_size (); | |
9af5ce0c | 1144 | invariant_table[DF_REF_ID (ref)] = inv; |
3d6b8be7 | 1145 | } |
3a0ecac2 | 1146 | } |
1147 | ||
c2aa3ceb | 1148 | /* Record registers used in INSN that have a unique invariant definition. */ |
3a0ecac2 | 1149 | |
1150 | static void | |
ff395cd9 | 1151 | record_uses (rtx_insn *insn) |
3a0ecac2 | 1152 | { |
158b6cc9 | 1153 | struct df_insn_info *insn_info = DF_INSN_INFO_GET (insn); |
be10bb5a | 1154 | df_ref use; |
3d6b8be7 | 1155 | struct invariant *inv; |
1156 | ||
be10bb5a | 1157 | FOR_EACH_INSN_INFO_USE (use, insn_info) |
3072d30e | 1158 | { |
3072d30e | 1159 | inv = invariant_for_use (use); |
1160 | if (inv) | |
68461c19 | 1161 | record_use (inv->def, use); |
3072d30e | 1162 | } |
be10bb5a | 1163 | FOR_EACH_INSN_INFO_EQ_USE (use, insn_info) |
3a0ecac2 | 1164 | { |
3d6b8be7 | 1165 | inv = invariant_for_use (use); |
1166 | if (inv) | |
68461c19 | 1167 | record_use (inv->def, use); |
3a0ecac2 | 1168 | } |
1169 | } | |
1170 | ||
1171 | /* Finds invariants in INSN. ALWAYS_REACHED is true if the insn is always | |
1172 | executed. ALWAYS_EXECUTED is true if the insn is always executed, | |
c2aa3ceb | 1173 | unless the program ends due to a function call. */ |
3a0ecac2 | 1174 | |
1175 | static void | |
ff395cd9 | 1176 | find_invariants_insn (rtx_insn *insn, bool always_reached, bool always_executed) |
3a0ecac2 | 1177 | { |
c2aa3ceb | 1178 | find_invariant_insn (insn, always_reached, always_executed); |
1179 | record_uses (insn); | |
3a0ecac2 | 1180 | } |
1181 | ||
1182 | /* Finds invariants in basic block BB. ALWAYS_REACHED is true if the | |
1183 | basic block is always executed. ALWAYS_EXECUTED is true if the basic | |
1184 | block is always executed, unless the program ends due to a function | |
c2aa3ceb | 1185 | call. */ |
3a0ecac2 | 1186 | |
1187 | static void | |
c2aa3ceb | 1188 | find_invariants_bb (basic_block bb, bool always_reached, bool always_executed) |
3a0ecac2 | 1189 | { |
ff395cd9 | 1190 | rtx_insn *insn; |
3a0ecac2 | 1191 | |
1192 | FOR_BB_INSNS (bb, insn) | |
1193 | { | |
9845d120 | 1194 | if (!NONDEBUG_INSN_P (insn)) |
3a0ecac2 | 1195 | continue; |
1196 | ||
c2aa3ceb | 1197 | find_invariants_insn (insn, always_reached, always_executed); |
3a0ecac2 | 1198 | |
1199 | if (always_reached | |
6d7dc5b9 | 1200 | && CALL_P (insn) |
9c2a0c05 | 1201 | && (RTL_LOOPING_CONST_OR_PURE_CALL_P (insn) |
1202 | || ! RTL_CONST_OR_PURE_CALL_P (insn))) | |
3a0ecac2 | 1203 | always_reached = false; |
1204 | } | |
1205 | } | |
1206 | ||
1207 | /* Finds invariants in LOOP with body BODY. ALWAYS_REACHED is the bitmap of | |
1208 | basic blocks in BODY that are always executed. ALWAYS_EXECUTED is the | |
1209 | bitmap of basic blocks in BODY that are always executed unless the program | |
c2aa3ceb | 1210 | ends due to a function call. */ |
3a0ecac2 | 1211 | |
1212 | static void | |
2e966e2a | 1213 | find_invariants_body (class loop *loop, basic_block *body, |
c2aa3ceb | 1214 | bitmap always_reached, bitmap always_executed) |
3a0ecac2 | 1215 | { |
1216 | unsigned i; | |
1217 | ||
1218 | for (i = 0; i < loop->num_nodes; i++) | |
1219 | find_invariants_bb (body[i], | |
1220 | bitmap_bit_p (always_reached, i), | |
c2aa3ceb | 1221 | bitmap_bit_p (always_executed, i)); |
3a0ecac2 | 1222 | } |
1223 | ||
c2aa3ceb | 1224 | /* Finds invariants in LOOP. */ |
3a0ecac2 | 1225 | |
1226 | static void | |
2e966e2a | 1227 | find_invariants (class loop *loop) |
3a0ecac2 | 1228 | { |
035def86 | 1229 | auto_bitmap may_exit; |
1230 | auto_bitmap always_reached; | |
1231 | auto_bitmap has_exit; | |
1232 | auto_bitmap always_executed; | |
3a0ecac2 | 1233 | basic_block *body = get_loop_body_in_dom_order (loop); |
1234 | ||
1235 | find_exits (loop, body, may_exit, has_exit); | |
1236 | compute_always_reached (loop, body, may_exit, always_reached); | |
1237 | compute_always_reached (loop, body, has_exit, always_executed); | |
1238 | ||
67e23d6f | 1239 | find_defs (loop); |
c2aa3ceb | 1240 | find_invariants_body (loop, body, always_reached, always_executed); |
3d6b8be7 | 1241 | merge_identical_invariants (); |
3a0ecac2 | 1242 | |
3a0ecac2 | 1243 | free (body); |
1244 | } | |
1245 | ||
1246 | /* Frees a list of uses USE. */ | |
1247 | ||
1248 | static void | |
1249 | free_use_list (struct use *use) | |
1250 | { | |
1251 | struct use *next; | |
1252 | ||
1253 | for (; use; use = next) | |
1254 | { | |
1255 | next = use->next; | |
1256 | free (use); | |
1257 | } | |
1258 | } | |
1259 | ||
66d9a7b9 | 1260 | /* Return pressure class and number of hard registers (through *NREGS) |
e8eed2f8 | 1261 | for destination of INSN. */ |
1262 | static enum reg_class | |
ff395cd9 | 1263 | get_pressure_class_and_nregs (rtx_insn *insn, int *nregs) |
e8eed2f8 | 1264 | { |
1265 | rtx reg; | |
66d9a7b9 | 1266 | enum reg_class pressure_class; |
e8eed2f8 | 1267 | rtx set = single_set (insn); |
48e1416a | 1268 | |
e8eed2f8 | 1269 | /* Considered invariant insns have only one set. */ |
1270 | gcc_assert (set != NULL_RTX); | |
1271 | reg = SET_DEST (set); | |
1272 | if (GET_CODE (reg) == SUBREG) | |
1273 | reg = SUBREG_REG (reg); | |
1274 | if (MEM_P (reg)) | |
1275 | { | |
1276 | *nregs = 0; | |
66d9a7b9 | 1277 | pressure_class = NO_REGS; |
e8eed2f8 | 1278 | } |
1279 | else | |
1280 | { | |
1281 | if (! REG_P (reg)) | |
1282 | reg = NULL_RTX; | |
1283 | if (reg == NULL_RTX) | |
66d9a7b9 | 1284 | pressure_class = GENERAL_REGS; |
e8eed2f8 | 1285 | else |
66d9a7b9 | 1286 | { |
1287 | pressure_class = reg_allocno_class (REGNO (reg)); | |
1288 | pressure_class = ira_pressure_class_translate[pressure_class]; | |
1289 | } | |
1290 | *nregs | |
1291 | = ira_reg_class_max_nregs[pressure_class][GET_MODE (SET_SRC (set))]; | |
e8eed2f8 | 1292 | } |
66d9a7b9 | 1293 | return pressure_class; |
e8eed2f8 | 1294 | } |
1295 | ||
3a0ecac2 | 1296 | /* Calculates cost and number of registers needed for moving invariant INV |
e234921f | 1297 | out of the loop and stores them to *COST and *REGS_NEEDED. *CL will be |
1298 | the REG_CLASS of INV. Return | |
1299 | -1: if INV is invalid. | |
1300 | 0: if INV and its depends_on have same reg_class | |
1301 | 1: if INV and its depends_on have different reg_classes. */ | |
3a0ecac2 | 1302 | |
e234921f | 1303 | static int |
1304 | get_inv_cost (struct invariant *inv, int *comp_cost, unsigned *regs_needed, | |
1305 | enum reg_class *cl) | |
3a0ecac2 | 1306 | { |
e8eed2f8 | 1307 | int i, acomp_cost; |
1308 | unsigned aregs_needed[N_REG_CLASSES]; | |
3a0ecac2 | 1309 | unsigned depno; |
1310 | struct invariant *dep; | |
0cc4271a | 1311 | bitmap_iterator bi; |
e234921f | 1312 | int ret = 1; |
3a0ecac2 | 1313 | |
3d6b8be7 | 1314 | /* Find the representative of the class of the equivalent invariants. */ |
f1f41a6c | 1315 | inv = invariants[inv->eqto]; |
3d6b8be7 | 1316 | |
3a0ecac2 | 1317 | *comp_cost = 0; |
e8eed2f8 | 1318 | if (! flag_ira_loop_pressure) |
1319 | regs_needed[0] = 0; | |
1320 | else | |
1321 | { | |
66d9a7b9 | 1322 | for (i = 0; i < ira_pressure_classes_num; i++) |
1323 | regs_needed[ira_pressure_classes[i]] = 0; | |
e8eed2f8 | 1324 | } |
1325 | ||
3a0ecac2 | 1326 | if (inv->move |
1327 | || inv->stamp == actual_stamp) | |
e234921f | 1328 | return -1; |
3a0ecac2 | 1329 | inv->stamp = actual_stamp; |
1330 | ||
e8eed2f8 | 1331 | if (! flag_ira_loop_pressure) |
1332 | regs_needed[0]++; | |
1333 | else | |
1334 | { | |
1335 | int nregs; | |
66d9a7b9 | 1336 | enum reg_class pressure_class; |
e8eed2f8 | 1337 | |
66d9a7b9 | 1338 | pressure_class = get_pressure_class_and_nregs (inv->insn, &nregs); |
1339 | regs_needed[pressure_class] += nregs; | |
e234921f | 1340 | *cl = pressure_class; |
1341 | ret = 0; | |
e8eed2f8 | 1342 | } |
1343 | ||
68461c19 | 1344 | if (!inv->cheap_address |
09c7ce53 | 1345 | || inv->def->n_uses == 0 |
ee3ee950 | 1346 | || inv->def->n_addr_uses < inv->def->n_uses |
1347 | /* Count cost if the inv can't be propagated into address uses. */ | |
1348 | || !inv->def->can_prop_to_addr_uses) | |
f69fbf74 | 1349 | (*comp_cost) += inv->cost * inv->eqno; |
3a0ecac2 | 1350 | |
e207fd7a | 1351 | #ifdef STACK_REGS |
1352 | { | |
1353 | /* Hoisting constant pool constants into stack regs may cost more than | |
1354 | just single register. On x87, the balance is affected both by the | |
334ec2d8 | 1355 | small number of FP registers, and by its register stack organization, |
e207fd7a | 1356 | that forces us to add compensation code in and around the loop to |
1357 | shuffle the operands to the top of stack before use, and pop them | |
1358 | from the stack after the loop finishes. | |
1359 | ||
1360 | To model this effect, we increase the number of registers needed for | |
1361 | stack registers by two: one register push, and one register pop. | |
1362 | This usually has the effect that FP constant loads from the constant | |
1363 | pool are not moved out of the loop. | |
1364 | ||
f4d3c071 | 1365 | Note that this also means that dependent invariants cannot be moved. |
e207fd7a | 1366 | However, the primary purpose of this pass is to move loop invariant |
1367 | address arithmetic out of loops, and address arithmetic that depends | |
1368 | on floating point constants is unlikely to ever occur. */ | |
1369 | rtx set = single_set (inv->insn); | |
1370 | if (set | |
e8eed2f8 | 1371 | && IS_STACK_MODE (GET_MODE (SET_SRC (set))) |
1372 | && constant_pool_constant_p (SET_SRC (set))) | |
1373 | { | |
1374 | if (flag_ira_loop_pressure) | |
66d9a7b9 | 1375 | regs_needed[ira_stack_reg_pressure_class] += 2; |
e8eed2f8 | 1376 | else |
1377 | regs_needed[0] += 2; | |
1378 | } | |
e207fd7a | 1379 | } |
1380 | #endif | |
1381 | ||
0cc4271a | 1382 | EXECUTE_IF_SET_IN_BITMAP (inv->depends_on, 0, depno, bi) |
3a0ecac2 | 1383 | { |
e8eed2f8 | 1384 | bool check_p; |
e234921f | 1385 | enum reg_class dep_cl = ALL_REGS; |
1386 | int dep_ret; | |
e8eed2f8 | 1387 | |
f1f41a6c | 1388 | dep = invariants[depno]; |
3a0ecac2 | 1389 | |
10a11071 | 1390 | /* If DEP is moved out of the loop, it is not a depends_on any more. */ |
1391 | if (dep->move) | |
1392 | continue; | |
1393 | ||
e234921f | 1394 | dep_ret = get_inv_cost (dep, &acomp_cost, aregs_needed, &dep_cl); |
3a0ecac2 | 1395 | |
e8eed2f8 | 1396 | if (! flag_ira_loop_pressure) |
1397 | check_p = aregs_needed[0] != 0; | |
1398 | else | |
1399 | { | |
66d9a7b9 | 1400 | for (i = 0; i < ira_pressure_classes_num; i++) |
1401 | if (aregs_needed[ira_pressure_classes[i]] != 0) | |
e8eed2f8 | 1402 | break; |
66d9a7b9 | 1403 | check_p = i < ira_pressure_classes_num; |
e234921f | 1404 | |
1405 | if ((dep_ret == 1) || ((dep_ret == 0) && (*cl != dep_cl))) | |
1406 | { | |
1407 | *cl = ALL_REGS; | |
1408 | ret = 1; | |
1409 | } | |
e8eed2f8 | 1410 | } |
1411 | if (check_p | |
3a0ecac2 | 1412 | /* We need to check always_executed, since if the original value of |
1413 | the invariant may be preserved, we may need to keep it in a | |
1414 | separate register. TODO check whether the register has an | |
1415 | use outside of the loop. */ | |
1416 | && dep->always_executed | |
1417 | && !dep->def->uses->next) | |
1418 | { | |
1419 | /* If this is a single use, after moving the dependency we will not | |
1420 | need a new register. */ | |
e8eed2f8 | 1421 | if (! flag_ira_loop_pressure) |
1422 | aregs_needed[0]--; | |
1423 | else | |
1424 | { | |
1425 | int nregs; | |
66d9a7b9 | 1426 | enum reg_class pressure_class; |
e8eed2f8 | 1427 | |
66d9a7b9 | 1428 | pressure_class = get_pressure_class_and_nregs (inv->insn, &nregs); |
1429 | aregs_needed[pressure_class] -= nregs; | |
e8eed2f8 | 1430 | } |
3a0ecac2 | 1431 | } |
1432 | ||
e8eed2f8 | 1433 | if (! flag_ira_loop_pressure) |
1434 | regs_needed[0] += aregs_needed[0]; | |
1435 | else | |
1436 | { | |
66d9a7b9 | 1437 | for (i = 0; i < ira_pressure_classes_num; i++) |
1438 | regs_needed[ira_pressure_classes[i]] | |
1439 | += aregs_needed[ira_pressure_classes[i]]; | |
e8eed2f8 | 1440 | } |
3a0ecac2 | 1441 | (*comp_cost) += acomp_cost; |
0cc4271a | 1442 | } |
e234921f | 1443 | return ret; |
3a0ecac2 | 1444 | } |
1445 | ||
1446 | /* Calculates gain for eliminating invariant INV. REGS_USED is the number | |
25153338 | 1447 | of registers used in the loop, NEW_REGS is the number of new variables |
1448 | already added due to the invariant motion. The number of registers needed | |
a6b74a67 | 1449 | for it is stored in *REGS_NEEDED. SPEED and CALL_P are flags passed |
1450 | through to estimate_reg_pressure_cost. */ | |
3a0ecac2 | 1451 | |
1452 | static int | |
1453 | gain_for_invariant (struct invariant *inv, unsigned *regs_needed, | |
a6b74a67 | 1454 | unsigned *new_regs, unsigned regs_used, |
1455 | bool speed, bool call_p) | |
3a0ecac2 | 1456 | { |
1457 | int comp_cost, size_cost; | |
a561ec10 | 1458 | /* Workaround -Wmaybe-uninitialized false positive during |
1459 | profiledbootstrap by initializing it. */ | |
1460 | enum reg_class cl = NO_REGS; | |
e234921f | 1461 | int ret; |
3a0ecac2 | 1462 | |
3a0ecac2 | 1463 | actual_stamp++; |
1464 | ||
e234921f | 1465 | ret = get_inv_cost (inv, &comp_cost, regs_needed, &cl); |
e8eed2f8 | 1466 | |
1467 | if (! flag_ira_loop_pressure) | |
1468 | { | |
1469 | size_cost = (estimate_reg_pressure_cost (new_regs[0] + regs_needed[0], | |
a6b74a67 | 1470 | regs_used, speed, call_p) |
e8eed2f8 | 1471 | - estimate_reg_pressure_cost (new_regs[0], |
a6b74a67 | 1472 | regs_used, speed, call_p)); |
e8eed2f8 | 1473 | } |
e234921f | 1474 | else if (ret < 0) |
1475 | return -1; | |
1476 | else if ((ret == 0) && (cl == NO_REGS)) | |
1477 | /* Hoist it anyway since it does not impact register pressure. */ | |
1478 | return 1; | |
e8eed2f8 | 1479 | else |
1480 | { | |
1481 | int i; | |
66d9a7b9 | 1482 | enum reg_class pressure_class; |
e8eed2f8 | 1483 | |
66d9a7b9 | 1484 | for (i = 0; i < ira_pressure_classes_num; i++) |
e8eed2f8 | 1485 | { |
66d9a7b9 | 1486 | pressure_class = ira_pressure_classes[i]; |
e234921f | 1487 | |
1488 | if (!reg_classes_intersect_p (pressure_class, cl)) | |
1489 | continue; | |
1490 | ||
66d9a7b9 | 1491 | if ((int) new_regs[pressure_class] |
1492 | + (int) regs_needed[pressure_class] | |
1493 | + LOOP_DATA (curr_loop)->max_reg_pressure[pressure_class] | |
e8eed2f8 | 1494 | + IRA_LOOP_RESERVED_REGS |
1072fecf | 1495 | > ira_class_hard_regs_num[pressure_class]) |
e8eed2f8 | 1496 | break; |
1497 | } | |
66d9a7b9 | 1498 | if (i < ira_pressure_classes_num) |
e8eed2f8 | 1499 | /* There will be register pressure excess and we want not to |
1500 | make this loop invariant motion. All loop invariants with | |
1501 | non-positive gains will be rejected in function | |
1502 | find_invariants_to_move. Therefore we return the negative | |
1503 | number here. | |
1504 | ||
1505 | One could think that this rejects also expensive loop | |
1506 | invariant motions and this will hurt code performance. | |
1507 | However numerous experiments with different heuristics | |
1508 | taking invariant cost into account did not confirm this | |
1509 | assumption. There are possible explanations for this | |
1510 | result: | |
1511 | o probably all expensive invariants were already moved out | |
1512 | of the loop by PRE and gimple invariant motion pass. | |
1513 | o expensive invariant execution will be hidden by insn | |
1514 | scheduling or OOO processor hardware because usually such | |
1515 | invariants have a lot of freedom to be executed | |
1516 | out-of-order. | |
1517 | Another reason for ignoring invariant cost vs spilling cost | |
1518 | heuristics is also in difficulties to evaluate accurately | |
1519 | spill cost at this stage. */ | |
1520 | return -1; | |
1521 | else | |
1522 | size_cost = 0; | |
1523 | } | |
3a0ecac2 | 1524 | |
1525 | return comp_cost - size_cost; | |
1526 | } | |
1527 | ||
1528 | /* Finds invariant with best gain for moving. Returns the gain, stores | |
1529 | the invariant in *BEST and number of registers needed for it to | |
25153338 | 1530 | *REGS_NEEDED. REGS_USED is the number of registers used in the loop. |
1531 | NEW_REGS is the number of new variables already added due to invariant | |
1532 | motion. */ | |
3a0ecac2 | 1533 | |
1534 | static int | |
1535 | best_gain_for_invariant (struct invariant **best, unsigned *regs_needed, | |
a6b74a67 | 1536 | unsigned *new_regs, unsigned regs_used, |
1537 | bool speed, bool call_p) | |
3a0ecac2 | 1538 | { |
1539 | struct invariant *inv; | |
e8eed2f8 | 1540 | int i, gain = 0, again; |
1541 | unsigned aregs_needed[N_REG_CLASSES], invno; | |
3a0ecac2 | 1542 | |
f1f41a6c | 1543 | FOR_EACH_VEC_ELT (invariants, invno, inv) |
3a0ecac2 | 1544 | { |
3a0ecac2 | 1545 | if (inv->move) |
1546 | continue; | |
1547 | ||
3d6b8be7 | 1548 | /* Only consider the "representatives" of equivalent invariants. */ |
1549 | if (inv->eqto != inv->invno) | |
1550 | continue; | |
1551 | ||
e8eed2f8 | 1552 | again = gain_for_invariant (inv, aregs_needed, new_regs, regs_used, |
a6b74a67 | 1553 | speed, call_p); |
3a0ecac2 | 1554 | if (again > gain) |
1555 | { | |
1556 | gain = again; | |
1557 | *best = inv; | |
e8eed2f8 | 1558 | if (! flag_ira_loop_pressure) |
1559 | regs_needed[0] = aregs_needed[0]; | |
1560 | else | |
1561 | { | |
66d9a7b9 | 1562 | for (i = 0; i < ira_pressure_classes_num; i++) |
1563 | regs_needed[ira_pressure_classes[i]] | |
1564 | = aregs_needed[ira_pressure_classes[i]]; | |
e8eed2f8 | 1565 | } |
3a0ecac2 | 1566 | } |
1567 | } | |
1568 | ||
1569 | return gain; | |
1570 | } | |
1571 | ||
1572 | /* Marks invariant INVNO and all its dependencies for moving. */ | |
1573 | ||
1574 | static void | |
e8eed2f8 | 1575 | set_move_mark (unsigned invno, int gain) |
3a0ecac2 | 1576 | { |
f1f41a6c | 1577 | struct invariant *inv = invariants[invno]; |
0cc4271a | 1578 | bitmap_iterator bi; |
3a0ecac2 | 1579 | |
3d6b8be7 | 1580 | /* Find the representative of the class of the equivalent invariants. */ |
f1f41a6c | 1581 | inv = invariants[inv->eqto]; |
3d6b8be7 | 1582 | |
3a0ecac2 | 1583 | if (inv->move) |
1584 | return; | |
1585 | inv->move = true; | |
1586 | ||
1587 | if (dump_file) | |
e8eed2f8 | 1588 | { |
1589 | if (gain >= 0) | |
1590 | fprintf (dump_file, "Decided to move invariant %d -- gain %d\n", | |
1591 | invno, gain); | |
1592 | else | |
1593 | fprintf (dump_file, "Decided to move dependent invariant %d\n", | |
1594 | invno); | |
1595 | }; | |
3a0ecac2 | 1596 | |
0cc4271a | 1597 | EXECUTE_IF_SET_IN_BITMAP (inv->depends_on, 0, invno, bi) |
1598 | { | |
e8eed2f8 | 1599 | set_move_mark (invno, -1); |
0cc4271a | 1600 | } |
3a0ecac2 | 1601 | } |
1602 | ||
c2aa3ceb | 1603 | /* Determines which invariants to move. */ |
3a0ecac2 | 1604 | |
1605 | static void | |
a6b74a67 | 1606 | find_invariants_to_move (bool speed, bool call_p) |
3a0ecac2 | 1607 | { |
e8eed2f8 | 1608 | int gain; |
1609 | unsigned i, regs_used, regs_needed[N_REG_CLASSES], new_regs[N_REG_CLASSES]; | |
3a0ecac2 | 1610 | struct invariant *inv = NULL; |
1611 | ||
f1f41a6c | 1612 | if (!invariants.length ()) |
3a0ecac2 | 1613 | return; |
1614 | ||
e8eed2f8 | 1615 | if (flag_ira_loop_pressure) |
48e1416a | 1616 | /* REGS_USED is actually never used when the flag is on. */ |
e8eed2f8 | 1617 | regs_used = 0; |
1618 | else | |
1619 | /* We do not really do a good job in estimating number of | |
1620 | registers used; we put some initial bound here to stand for | |
1621 | induction variables etc. that we do not detect. */ | |
3a0ecac2 | 1622 | { |
e8eed2f8 | 1623 | unsigned int n_regs = DF_REG_SIZE (df); |
1624 | ||
1625 | regs_used = 2; | |
48e1416a | 1626 | |
e8eed2f8 | 1627 | for (i = 0; i < n_regs; i++) |
3a0ecac2 | 1628 | { |
e8eed2f8 | 1629 | if (!DF_REGNO_FIRST_DEF (i) && DF_REGNO_LAST_USE (i)) |
1630 | { | |
1631 | /* This is a value that is used but not changed inside loop. */ | |
1632 | regs_used++; | |
1633 | } | |
3a0ecac2 | 1634 | } |
1635 | } | |
1636 | ||
e8eed2f8 | 1637 | if (! flag_ira_loop_pressure) |
1638 | new_regs[0] = regs_needed[0] = 0; | |
1639 | else | |
3a0ecac2 | 1640 | { |
66d9a7b9 | 1641 | for (i = 0; (int) i < ira_pressure_classes_num; i++) |
1642 | new_regs[ira_pressure_classes[i]] = 0; | |
e8eed2f8 | 1643 | } |
1644 | while ((gain = best_gain_for_invariant (&inv, regs_needed, | |
a6b74a67 | 1645 | new_regs, regs_used, |
1646 | speed, call_p)) > 0) | |
e8eed2f8 | 1647 | { |
1648 | set_move_mark (inv->invno, gain); | |
1649 | if (! flag_ira_loop_pressure) | |
1650 | new_regs[0] += regs_needed[0]; | |
1651 | else | |
1652 | { | |
66d9a7b9 | 1653 | for (i = 0; (int) i < ira_pressure_classes_num; i++) |
1654 | new_regs[ira_pressure_classes[i]] | |
1655 | += regs_needed[ira_pressure_classes[i]]; | |
e8eed2f8 | 1656 | } |
3a0ecac2 | 1657 | } |
1658 | } | |
1659 | ||
cc6541e2 | 1660 | /* Replace the uses, reached by the definition of invariant INV, by REG. |
1661 | ||
1662 | IN_GROUP is nonzero if this is part of a group of changes that must be | |
1663 | performed as a group. In that case, the changes will be stored. The | |
1664 | function `apply_change_group' will validate and apply the changes. */ | |
1665 | ||
1666 | static int | |
1667 | replace_uses (struct invariant *inv, rtx reg, bool in_group) | |
1668 | { | |
1669 | /* Replace the uses we know to be dominated. It saves work for copy | |
1670 | propagation, and also it is necessary so that dependent invariants | |
1671 | are computed right. */ | |
1672 | if (inv->def) | |
1673 | { | |
1674 | struct use *use; | |
1675 | for (use = inv->def->uses; use; use = use->next) | |
1676 | validate_change (use->insn, use->pos, reg, true); | |
1677 | ||
1678 | /* If we aren't part of a larger group, apply the changes now. */ | |
1679 | if (!in_group) | |
1680 | return apply_change_group (); | |
1681 | } | |
1682 | ||
1683 | return 1; | |
1684 | } | |
1685 | ||
570c7ca7 | 1686 | /* Whether invariant INV setting REG can be moved out of LOOP, at the end of |
1687 | the block preceding its header. */ | |
1688 | ||
1689 | static bool | |
2e966e2a | 1690 | can_move_invariant_reg (class loop *loop, struct invariant *inv, rtx reg) |
570c7ca7 | 1691 | { |
1692 | df_ref def, use; | |
1693 | unsigned int dest_regno, defs_in_loop_count = 0; | |
1694 | rtx_insn *insn = inv->insn; | |
1695 | basic_block bb = BLOCK_FOR_INSN (inv->insn); | |
1696 | ||
1697 | /* We ignore hard register and memory access for cost and complexity reasons. | |
1698 | Hard register are few at this stage and expensive to consider as they | |
1699 | require building a separate data flow. Memory access would require using | |
1700 | df_simulate_* and can_move_insns_across functions and is more complex. */ | |
1701 | if (!REG_P (reg) || HARD_REGISTER_P (reg)) | |
1702 | return false; | |
1703 | ||
1704 | /* Check whether the set is always executed. We could omit this condition if | |
1705 | we know that the register is unused outside of the loop, but it does not | |
1706 | seem worth finding out. */ | |
1707 | if (!inv->always_executed) | |
1708 | return false; | |
1709 | ||
1710 | /* Check that all uses that would be dominated by def are already dominated | |
1711 | by it. */ | |
1712 | dest_regno = REGNO (reg); | |
1713 | for (use = DF_REG_USE_CHAIN (dest_regno); use; use = DF_REF_NEXT_REG (use)) | |
1714 | { | |
1715 | rtx_insn *use_insn; | |
1716 | basic_block use_bb; | |
1717 | ||
1718 | use_insn = DF_REF_INSN (use); | |
1719 | use_bb = BLOCK_FOR_INSN (use_insn); | |
1720 | ||
1721 | /* Ignore instruction considered for moving. */ | |
1722 | if (use_insn == insn) | |
1723 | continue; | |
1724 | ||
1725 | /* Don't consider uses outside loop. */ | |
1726 | if (!flow_bb_inside_loop_p (loop, use_bb)) | |
1727 | continue; | |
1728 | ||
1729 | /* Don't move if a use is not dominated by def in insn. */ | |
1730 | if (use_bb == bb && DF_INSN_LUID (insn) >= DF_INSN_LUID (use_insn)) | |
1731 | return false; | |
1732 | if (!dominated_by_p (CDI_DOMINATORS, use_bb, bb)) | |
1733 | return false; | |
1734 | } | |
1735 | ||
1736 | /* Check for other defs. Any other def in the loop might reach a use | |
1737 | currently reached by the def in insn. */ | |
1738 | for (def = DF_REG_DEF_CHAIN (dest_regno); def; def = DF_REF_NEXT_REG (def)) | |
1739 | { | |
1740 | basic_block def_bb = DF_REF_BB (def); | |
1741 | ||
1742 | /* Defs in exit block cannot reach a use they weren't already. */ | |
1743 | if (single_succ_p (def_bb)) | |
1744 | { | |
1745 | basic_block def_bb_succ; | |
1746 | ||
1747 | def_bb_succ = single_succ (def_bb); | |
1748 | if (!flow_bb_inside_loop_p (loop, def_bb_succ)) | |
1749 | continue; | |
1750 | } | |
1751 | ||
1752 | if (++defs_in_loop_count > 1) | |
1753 | return false; | |
1754 | } | |
1755 | ||
1756 | return true; | |
1757 | } | |
1758 | ||
1e41d0e2 | 1759 | /* Move invariant INVNO out of the LOOP. Returns true if this succeeds, false |
1760 | otherwise. */ | |
1761 | ||
1762 | static bool | |
2e966e2a | 1763 | move_invariant_reg (class loop *loop, unsigned invno) |
3a0ecac2 | 1764 | { |
f1f41a6c | 1765 | struct invariant *inv = invariants[invno]; |
1766 | struct invariant *repr = invariants[inv->eqto]; | |
3a0ecac2 | 1767 | unsigned i; |
1768 | basic_block preheader = loop_preheader_edge (loop)->src; | |
c69c2a10 | 1769 | rtx reg, set, dest, note; |
0cc4271a | 1770 | bitmap_iterator bi; |
cc6541e2 | 1771 | int regno = -1; |
3a0ecac2 | 1772 | |
1e41d0e2 | 1773 | if (inv->reg) |
1774 | return true; | |
1775 | if (!repr->move) | |
1776 | return false; | |
cc6541e2 | 1777 | |
3d6b8be7 | 1778 | /* If this is a representative of the class of equivalent invariants, |
1779 | really move the invariant. Otherwise just replace its use with | |
1780 | the register used for the representative. */ | |
1781 | if (inv == repr) | |
3a0ecac2 | 1782 | { |
3d6b8be7 | 1783 | if (inv->depends_on) |
3a0ecac2 | 1784 | { |
3d6b8be7 | 1785 | EXECUTE_IF_SET_IN_BITMAP (inv->depends_on, 0, i, bi) |
1786 | { | |
1e41d0e2 | 1787 | if (!move_invariant_reg (loop, i)) |
1788 | goto fail; | |
3d6b8be7 | 1789 | } |
0cc4271a | 1790 | } |
3a0ecac2 | 1791 | |
570c7ca7 | 1792 | /* If possible, just move the set out of the loop. Otherwise, we |
1793 | need to create a temporary register. */ | |
3d6b8be7 | 1794 | set = single_set (inv->insn); |
e8eed2f8 | 1795 | reg = dest = SET_DEST (set); |
1796 | if (GET_CODE (reg) == SUBREG) | |
1797 | reg = SUBREG_REG (reg); | |
1798 | if (REG_P (reg)) | |
1799 | regno = REGNO (reg); | |
1800 | ||
734ac122 | 1801 | if (!can_move_invariant_reg (loop, inv, dest)) |
570c7ca7 | 1802 | { |
1803 | reg = gen_reg_rtx_and_attrs (dest); | |
3d6b8be7 | 1804 | |
570c7ca7 | 1805 | /* Try replacing the destination by a new pseudoregister. */ |
1806 | validate_change (inv->insn, &SET_DEST (set), reg, true); | |
cc6541e2 | 1807 | |
570c7ca7 | 1808 | /* As well as all the dominated uses. */ |
1809 | replace_uses (inv, reg, true); | |
cc6541e2 | 1810 | |
570c7ca7 | 1811 | /* And validate all the changes. */ |
1812 | if (!apply_change_group ()) | |
1813 | goto fail; | |
c69c2a10 | 1814 | |
570c7ca7 | 1815 | emit_insn_after (gen_move_insn (dest, reg), inv->insn); |
1816 | } | |
1817 | else if (dump_file) | |
1818 | fprintf (dump_file, "Invariant %d moved without introducing a new " | |
1819 | "temporary register\n", invno); | |
c69c2a10 | 1820 | reorder_insns (inv->insn, inv->insn, BB_END (preheader)); |
ff429db2 | 1821 | df_recompute_luids (preheader); |
c69c2a10 | 1822 | |
2521c084 | 1823 | /* If there is a REG_EQUAL note on the insn we just moved, and the |
1824 | insn is in a basic block that is not always executed or the note | |
1825 | contains something for which we don't know the invariant status, | |
1826 | the note may no longer be valid after we move the insn. Note that | |
1827 | uses in REG_EQUAL notes are taken into account in the computation | |
1828 | of invariants, so it is safe to retain the note even if it contains | |
1829 | register references for which we know the invariant status. */ | |
1830 | if ((note = find_reg_note (inv->insn, REG_EQUAL, NULL_RTX)) | |
1831 | && (!inv->always_executed | |
1832 | || !check_maybe_invariant (XEXP (note, 0)))) | |
c69c2a10 | 1833 | remove_note (inv->insn, note); |
e363ebc7 | 1834 | } |
1835 | else | |
1836 | { | |
1e41d0e2 | 1837 | if (!move_invariant_reg (loop, repr->invno)) |
1838 | goto fail; | |
3d6b8be7 | 1839 | reg = repr->reg; |
e8eed2f8 | 1840 | regno = repr->orig_regno; |
cc6541e2 | 1841 | if (!replace_uses (inv, reg, false)) |
1842 | goto fail; | |
3d6b8be7 | 1843 | set = single_set (inv->insn); |
e011eba9 | 1844 | emit_insn_after (gen_move_insn (SET_DEST (set), reg), inv->insn); |
1845 | delete_insn (inv->insn); | |
e363ebc7 | 1846 | } |
3a0ecac2 | 1847 | |
3d6b8be7 | 1848 | inv->reg = reg; |
e8eed2f8 | 1849 | inv->orig_regno = regno; |
3d6b8be7 | 1850 | |
1e41d0e2 | 1851 | return true; |
1852 | ||
1853 | fail: | |
1854 | /* If we failed, clear move flag, so that we do not try to move inv | |
1855 | again. */ | |
1856 | if (dump_file) | |
1857 | fprintf (dump_file, "Failed to move invariant %d\n", invno); | |
1858 | inv->move = false; | |
1859 | inv->reg = NULL_RTX; | |
e8eed2f8 | 1860 | inv->orig_regno = -1; |
3072d30e | 1861 | |
1e41d0e2 | 1862 | return false; |
3a0ecac2 | 1863 | } |
1864 | ||
1865 | /* Move selected invariant out of the LOOP. Newly created regs are marked | |
c2aa3ceb | 1866 | in TEMPORARY_REGS. */ |
3a0ecac2 | 1867 | |
1868 | static void | |
2e966e2a | 1869 | move_invariants (class loop *loop) |
3a0ecac2 | 1870 | { |
1871 | struct invariant *inv; | |
1872 | unsigned i; | |
1873 | ||
f1f41a6c | 1874 | FOR_EACH_VEC_ELT (invariants, i, inv) |
3d6b8be7 | 1875 | move_invariant_reg (loop, i); |
e8eed2f8 | 1876 | if (flag_ira_loop_pressure && resize_reg_info ()) |
1877 | { | |
f1f41a6c | 1878 | FOR_EACH_VEC_ELT (invariants, i, inv) |
e8eed2f8 | 1879 | if (inv->reg != NULL_RTX) |
1880 | { | |
1881 | if (inv->orig_regno >= 0) | |
1882 | setup_reg_classes (REGNO (inv->reg), | |
1883 | reg_preferred_class (inv->orig_regno), | |
1884 | reg_alternate_class (inv->orig_regno), | |
66d9a7b9 | 1885 | reg_allocno_class (inv->orig_regno)); |
e8eed2f8 | 1886 | else |
1887 | setup_reg_classes (REGNO (inv->reg), | |
1888 | GENERAL_REGS, NO_REGS, GENERAL_REGS); | |
1889 | } | |
1890 | } | |
9b316951 | 1891 | /* Remove the DF_UD_CHAIN problem added in find_defs before rescanning, |
1892 | to save a bit of compile time. */ | |
1893 | df_remove_problem (df_chain); | |
1894 | df_process_deferred_rescans (); | |
3a0ecac2 | 1895 | } |
1896 | ||
1897 | /* Initializes invariant motion data. */ | |
1898 | ||
1899 | static void | |
1900 | init_inv_motion_data (void) | |
1901 | { | |
1902 | actual_stamp = 1; | |
1903 | ||
f1f41a6c | 1904 | invariants.create (100); |
3a0ecac2 | 1905 | } |
1906 | ||
c2aa3ceb | 1907 | /* Frees the data allocated by invariant motion. */ |
3a0ecac2 | 1908 | |
1909 | static void | |
c2aa3ceb | 1910 | free_inv_motion_data (void) |
3a0ecac2 | 1911 | { |
1912 | unsigned i; | |
1913 | struct def *def; | |
1914 | struct invariant *inv; | |
1915 | ||
3072d30e | 1916 | check_invariant_table_size (); |
1917 | for (i = 0; i < DF_DEFS_TABLE_SIZE (); i++) | |
3a0ecac2 | 1918 | { |
3072d30e | 1919 | inv = invariant_table[i]; |
1920 | if (inv) | |
1921 | { | |
1922 | def = inv->def; | |
1923 | gcc_assert (def != NULL); | |
48e1416a | 1924 | |
3072d30e | 1925 | free_use_list (def->uses); |
1926 | free (def); | |
1927 | invariant_table[i] = NULL; | |
1928 | } | |
3a0ecac2 | 1929 | } |
1930 | ||
f1f41a6c | 1931 | FOR_EACH_VEC_ELT (invariants, i, inv) |
3a0ecac2 | 1932 | { |
27335ffd | 1933 | BITMAP_FREE (inv->depends_on); |
3a0ecac2 | 1934 | free (inv); |
1935 | } | |
f1f41a6c | 1936 | invariants.release (); |
3a0ecac2 | 1937 | } |
1938 | ||
c2aa3ceb | 1939 | /* Move the invariants out of the LOOP. */ |
3a0ecac2 | 1940 | |
1941 | static void | |
2e966e2a | 1942 | move_single_loop_invariants (class loop *loop) |
3a0ecac2 | 1943 | { |
1944 | init_inv_motion_data (); | |
1945 | ||
c2aa3ceb | 1946 | find_invariants (loop); |
a6b74a67 | 1947 | find_invariants_to_move (optimize_loop_for_speed_p (loop), |
1948 | LOOP_DATA (loop)->has_call); | |
c2aa3ceb | 1949 | move_invariants (loop); |
3a0ecac2 | 1950 | |
c2aa3ceb | 1951 | free_inv_motion_data (); |
3a0ecac2 | 1952 | } |
1953 | ||
1954 | /* Releases the auxiliary data for LOOP. */ | |
1955 | ||
1956 | static void | |
2e966e2a | 1957 | free_loop_data (class loop *loop) |
3a0ecac2 | 1958 | { |
2e966e2a | 1959 | class loop_data *data = LOOP_DATA (loop); |
8311e9d2 | 1960 | if (!data) |
1961 | return; | |
3a0ecac2 | 1962 | |
e8eed2f8 | 1963 | bitmap_clear (&LOOP_DATA (loop)->regs_ref); |
1964 | bitmap_clear (&LOOP_DATA (loop)->regs_live); | |
3a0ecac2 | 1965 | free (data); |
1966 | loop->aux = NULL; | |
1967 | } | |
1968 | ||
e8eed2f8 | 1969 | \f |
1970 | ||
1971 | /* Registers currently living. */ | |
1972 | static bitmap_head curr_regs_live; | |
1973 | ||
66d9a7b9 | 1974 | /* Current reg pressure for each pressure class. */ |
e8eed2f8 | 1975 | static int curr_reg_pressure[N_REG_CLASSES]; |
1976 | ||
1977 | /* Record all regs that are set in any one insn. Communication from | |
1978 | mark_reg_{store,clobber} and global_conflicts. Asm can refer to | |
1979 | all hard-registers. */ | |
1980 | static rtx regs_set[(FIRST_PSEUDO_REGISTER > MAX_RECOG_OPERANDS | |
1981 | ? FIRST_PSEUDO_REGISTER : MAX_RECOG_OPERANDS) * 2]; | |
1982 | /* Number of regs stored in the previous array. */ | |
1983 | static int n_regs_set; | |
1984 | ||
66d9a7b9 | 1985 | /* Return pressure class and number of needed hard registers (through |
48e1416a | 1986 | *NREGS) of register REGNO. */ |
e8eed2f8 | 1987 | static enum reg_class |
66d9a7b9 | 1988 | get_regno_pressure_class (int regno, int *nregs) |
e8eed2f8 | 1989 | { |
1990 | if (regno >= FIRST_PSEUDO_REGISTER) | |
1991 | { | |
66d9a7b9 | 1992 | enum reg_class pressure_class; |
e8eed2f8 | 1993 | |
66d9a7b9 | 1994 | pressure_class = reg_allocno_class (regno); |
1995 | pressure_class = ira_pressure_class_translate[pressure_class]; | |
1996 | *nregs | |
1997 | = ira_reg_class_max_nregs[pressure_class][PSEUDO_REGNO_MODE (regno)]; | |
1998 | return pressure_class; | |
e8eed2f8 | 1999 | } |
2000 | else if (! TEST_HARD_REG_BIT (ira_no_alloc_regs, regno) | |
2001 | && ! TEST_HARD_REG_BIT (eliminable_regset, regno)) | |
2002 | { | |
2003 | *nregs = 1; | |
66d9a7b9 | 2004 | return ira_pressure_class_translate[REGNO_REG_CLASS (regno)]; |
e8eed2f8 | 2005 | } |
2006 | else | |
2007 | { | |
2008 | *nregs = 0; | |
2009 | return NO_REGS; | |
2010 | } | |
2011 | } | |
2012 | ||
2013 | /* Increase (if INCR_P) or decrease current register pressure for | |
2014 | register REGNO. */ | |
2015 | static void | |
2016 | change_pressure (int regno, bool incr_p) | |
2017 | { | |
2018 | int nregs; | |
66d9a7b9 | 2019 | enum reg_class pressure_class; |
e8eed2f8 | 2020 | |
66d9a7b9 | 2021 | pressure_class = get_regno_pressure_class (regno, &nregs); |
e8eed2f8 | 2022 | if (! incr_p) |
66d9a7b9 | 2023 | curr_reg_pressure[pressure_class] -= nregs; |
e8eed2f8 | 2024 | else |
2025 | { | |
66d9a7b9 | 2026 | curr_reg_pressure[pressure_class] += nregs; |
2027 | if (LOOP_DATA (curr_loop)->max_reg_pressure[pressure_class] | |
2028 | < curr_reg_pressure[pressure_class]) | |
2029 | LOOP_DATA (curr_loop)->max_reg_pressure[pressure_class] | |
2030 | = curr_reg_pressure[pressure_class]; | |
e8eed2f8 | 2031 | } |
2032 | } | |
2033 | ||
2034 | /* Mark REGNO birth. */ | |
2035 | static void | |
2036 | mark_regno_live (int regno) | |
2037 | { | |
2e966e2a | 2038 | class loop *loop; |
e8eed2f8 | 2039 | |
2040 | for (loop = curr_loop; | |
2041 | loop != current_loops->tree_root; | |
2042 | loop = loop_outer (loop)) | |
2043 | bitmap_set_bit (&LOOP_DATA (loop)->regs_live, regno); | |
6ef9bbe0 | 2044 | if (!bitmap_set_bit (&curr_regs_live, regno)) |
e8eed2f8 | 2045 | return; |
e8eed2f8 | 2046 | change_pressure (regno, true); |
2047 | } | |
2048 | ||
2049 | /* Mark REGNO death. */ | |
2050 | static void | |
2051 | mark_regno_death (int regno) | |
2052 | { | |
6ef9bbe0 | 2053 | if (! bitmap_clear_bit (&curr_regs_live, regno)) |
e8eed2f8 | 2054 | return; |
e8eed2f8 | 2055 | change_pressure (regno, false); |
2056 | } | |
2057 | ||
2058 | /* Mark setting register REG. */ | |
2059 | static void | |
2060 | mark_reg_store (rtx reg, const_rtx setter ATTRIBUTE_UNUSED, | |
2061 | void *data ATTRIBUTE_UNUSED) | |
2062 | { | |
e8eed2f8 | 2063 | if (GET_CODE (reg) == SUBREG) |
2064 | reg = SUBREG_REG (reg); | |
2065 | ||
2066 | if (! REG_P (reg)) | |
2067 | return; | |
2068 | ||
2069 | regs_set[n_regs_set++] = reg; | |
2070 | ||
6a298741 | 2071 | unsigned int end_regno = END_REGNO (reg); |
2072 | for (unsigned int regno = REGNO (reg); regno < end_regno; ++regno) | |
e8eed2f8 | 2073 | mark_regno_live (regno); |
e8eed2f8 | 2074 | } |
2075 | ||
2076 | /* Mark clobbering register REG. */ | |
2077 | static void | |
2078 | mark_reg_clobber (rtx reg, const_rtx setter, void *data) | |
2079 | { | |
2080 | if (GET_CODE (setter) == CLOBBER) | |
2081 | mark_reg_store (reg, setter, data); | |
2082 | } | |
2083 | ||
2084 | /* Mark register REG death. */ | |
2085 | static void | |
2086 | mark_reg_death (rtx reg) | |
2087 | { | |
6a298741 | 2088 | unsigned int end_regno = END_REGNO (reg); |
2089 | for (unsigned int regno = REGNO (reg); regno < end_regno; ++regno) | |
e8eed2f8 | 2090 | mark_regno_death (regno); |
e8eed2f8 | 2091 | } |
2092 | ||
2093 | /* Mark occurrence of registers in X for the current loop. */ | |
2094 | static void | |
2095 | mark_ref_regs (rtx x) | |
2096 | { | |
2097 | RTX_CODE code; | |
2098 | int i; | |
2099 | const char *fmt; | |
2100 | ||
2101 | if (!x) | |
2102 | return; | |
2103 | ||
2104 | code = GET_CODE (x); | |
2105 | if (code == REG) | |
2106 | { | |
2e966e2a | 2107 | class loop *loop; |
48e1416a | 2108 | |
e8eed2f8 | 2109 | for (loop = curr_loop; |
2110 | loop != current_loops->tree_root; | |
2111 | loop = loop_outer (loop)) | |
2112 | bitmap_set_bit (&LOOP_DATA (loop)->regs_ref, REGNO (x)); | |
2113 | return; | |
2114 | } | |
2115 | ||
2116 | fmt = GET_RTX_FORMAT (code); | |
2117 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) | |
2118 | if (fmt[i] == 'e') | |
2119 | mark_ref_regs (XEXP (x, i)); | |
2120 | else if (fmt[i] == 'E') | |
2121 | { | |
2122 | int j; | |
48e1416a | 2123 | |
e8eed2f8 | 2124 | for (j = 0; j < XVECLEN (x, i); j++) |
2125 | mark_ref_regs (XVECEXP (x, i, j)); | |
2126 | } | |
2127 | } | |
2128 | ||
2129 | /* Calculate register pressure in the loops. */ | |
2130 | static void | |
2131 | calculate_loop_reg_pressure (void) | |
2132 | { | |
2133 | int i; | |
2134 | unsigned int j; | |
2135 | bitmap_iterator bi; | |
2136 | basic_block bb; | |
ff395cd9 | 2137 | rtx_insn *insn; |
2138 | rtx link; | |
2e966e2a | 2139 | class loop *loop, *parent; |
e8eed2f8 | 2140 | |
f21d4d00 | 2141 | FOR_EACH_LOOP (loop, 0) |
e8eed2f8 | 2142 | if (loop->aux == NULL) |
2143 | { | |
2e966e2a | 2144 | loop->aux = xcalloc (1, sizeof (class loop_data)); |
e8eed2f8 | 2145 | bitmap_initialize (&LOOP_DATA (loop)->regs_ref, ®_obstack); |
2146 | bitmap_initialize (&LOOP_DATA (loop)->regs_live, ®_obstack); | |
2147 | } | |
3b3a5e5f | 2148 | ira_setup_eliminable_regset (); |
e8eed2f8 | 2149 | bitmap_initialize (&curr_regs_live, ®_obstack); |
fc00614f | 2150 | FOR_EACH_BB_FN (bb, cfun) |
e8eed2f8 | 2151 | { |
2152 | curr_loop = bb->loop_father; | |
2153 | if (curr_loop == current_loops->tree_root) | |
2154 | continue; | |
2155 | ||
2156 | for (loop = curr_loop; | |
2157 | loop != current_loops->tree_root; | |
2158 | loop = loop_outer (loop)) | |
2159 | bitmap_ior_into (&LOOP_DATA (loop)->regs_live, DF_LR_IN (bb)); | |
2160 | ||
2161 | bitmap_copy (&curr_regs_live, DF_LR_IN (bb)); | |
66d9a7b9 | 2162 | for (i = 0; i < ira_pressure_classes_num; i++) |
2163 | curr_reg_pressure[ira_pressure_classes[i]] = 0; | |
e8eed2f8 | 2164 | EXECUTE_IF_SET_IN_BITMAP (&curr_regs_live, 0, j, bi) |
2165 | change_pressure (j, true); | |
2166 | ||
2167 | FOR_BB_INSNS (bb, insn) | |
2168 | { | |
c6a55b97 | 2169 | if (! NONDEBUG_INSN_P (insn)) |
e8eed2f8 | 2170 | continue; |
2171 | ||
2172 | mark_ref_regs (PATTERN (insn)); | |
2173 | n_regs_set = 0; | |
2174 | note_stores (PATTERN (insn), mark_reg_clobber, NULL); | |
48e1416a | 2175 | |
e8eed2f8 | 2176 | /* Mark any registers dead after INSN as dead now. */ |
48e1416a | 2177 | |
e8eed2f8 | 2178 | for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) |
2179 | if (REG_NOTE_KIND (link) == REG_DEAD) | |
2180 | mark_reg_death (XEXP (link, 0)); | |
48e1416a | 2181 | |
e8eed2f8 | 2182 | /* Mark any registers set in INSN as live, |
2183 | and mark them as conflicting with all other live regs. | |
2184 | Clobbers are processed again, so they conflict with | |
2185 | the registers that are set. */ | |
48e1416a | 2186 | |
e8eed2f8 | 2187 | note_stores (PATTERN (insn), mark_reg_store, NULL); |
48e1416a | 2188 | |
32aa77d9 | 2189 | if (AUTO_INC_DEC) |
2190 | for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) | |
2191 | if (REG_NOTE_KIND (link) == REG_INC) | |
2192 | mark_reg_store (XEXP (link, 0), NULL_RTX, NULL); | |
2193 | ||
e8eed2f8 | 2194 | while (n_regs_set-- > 0) |
2195 | { | |
2196 | rtx note = find_regno_note (insn, REG_UNUSED, | |
2197 | REGNO (regs_set[n_regs_set])); | |
2198 | if (! note) | |
2199 | continue; | |
48e1416a | 2200 | |
e8eed2f8 | 2201 | mark_reg_death (XEXP (note, 0)); |
2202 | } | |
2203 | } | |
2204 | } | |
6e6e5c14 | 2205 | bitmap_release (&curr_regs_live); |
e8eed2f8 | 2206 | if (flag_ira_region == IRA_REGION_MIXED |
2207 | || flag_ira_region == IRA_REGION_ALL) | |
f21d4d00 | 2208 | FOR_EACH_LOOP (loop, 0) |
e8eed2f8 | 2209 | { |
2210 | EXECUTE_IF_SET_IN_BITMAP (&LOOP_DATA (loop)->regs_live, 0, j, bi) | |
2211 | if (! bitmap_bit_p (&LOOP_DATA (loop)->regs_ref, j)) | |
2212 | { | |
66d9a7b9 | 2213 | enum reg_class pressure_class; |
e8eed2f8 | 2214 | int nregs; |
2215 | ||
66d9a7b9 | 2216 | pressure_class = get_regno_pressure_class (j, &nregs); |
2217 | LOOP_DATA (loop)->max_reg_pressure[pressure_class] -= nregs; | |
e8eed2f8 | 2218 | } |
2219 | } | |
2220 | if (dump_file == NULL) | |
2221 | return; | |
f21d4d00 | 2222 | FOR_EACH_LOOP (loop, 0) |
e8eed2f8 | 2223 | { |
2224 | parent = loop_outer (loop); | |
2225 | fprintf (dump_file, "\n Loop %d (parent %d, header bb%d, depth %d)\n", | |
2226 | loop->num, (parent == NULL ? -1 : parent->num), | |
2227 | loop->header->index, loop_depth (loop)); | |
2228 | fprintf (dump_file, "\n ref. regnos:"); | |
2229 | EXECUTE_IF_SET_IN_BITMAP (&LOOP_DATA (loop)->regs_ref, 0, j, bi) | |
2230 | fprintf (dump_file, " %d", j); | |
2231 | fprintf (dump_file, "\n live regnos:"); | |
2232 | EXECUTE_IF_SET_IN_BITMAP (&LOOP_DATA (loop)->regs_live, 0, j, bi) | |
2233 | fprintf (dump_file, " %d", j); | |
2234 | fprintf (dump_file, "\n Pressure:"); | |
66d9a7b9 | 2235 | for (i = 0; (int) i < ira_pressure_classes_num; i++) |
e8eed2f8 | 2236 | { |
66d9a7b9 | 2237 | enum reg_class pressure_class; |
48e1416a | 2238 | |
66d9a7b9 | 2239 | pressure_class = ira_pressure_classes[i]; |
2240 | if (LOOP_DATA (loop)->max_reg_pressure[pressure_class] == 0) | |
e8eed2f8 | 2241 | continue; |
66d9a7b9 | 2242 | fprintf (dump_file, " %s=%d", reg_class_names[pressure_class], |
2243 | LOOP_DATA (loop)->max_reg_pressure[pressure_class]); | |
e8eed2f8 | 2244 | } |
2245 | fprintf (dump_file, "\n"); | |
2246 | } | |
2247 | } | |
2248 | ||
2249 | \f | |
2250 | ||
7194de72 | 2251 | /* Move the invariants out of the loops. */ |
3a0ecac2 | 2252 | |
2253 | void | |
7194de72 | 2254 | move_loop_invariants (void) |
3a0ecac2 | 2255 | { |
2e966e2a | 2256 | class loop *loop; |
c2aa3ceb | 2257 | |
9b316951 | 2258 | if (optimize == 1) |
2259 | df_live_add_problem (); | |
2260 | /* ??? This is a hack. We should only need to call df_live_set_all_dirty | |
2261 | for optimize == 1, but can_move_invariant_reg relies on DF_INSN_LUID | |
2262 | being up-to-date. That isn't always true (even after df_analyze) | |
2263 | because df_process_deferred_rescans doesn't necessarily cause | |
2264 | blocks to be rescanned. */ | |
2265 | df_live_set_all_dirty (); | |
e8eed2f8 | 2266 | if (flag_ira_loop_pressure) |
2267 | { | |
2268 | df_analyze (); | |
66d9a7b9 | 2269 | regstat_init_n_sets_and_refs (); |
1ec78e16 | 2270 | ira_set_pseudo_classes (true, dump_file); |
e8eed2f8 | 2271 | calculate_loop_reg_pressure (); |
66d9a7b9 | 2272 | regstat_free_n_sets_and_refs (); |
e8eed2f8 | 2273 | } |
3072d30e | 2274 | df_set_flags (DF_EQ_NOTES + DF_DEFER_INSN_RESCAN); |
3a0ecac2 | 2275 | /* Process the loops, innermost first. */ |
f21d4d00 | 2276 | FOR_EACH_LOOP (loop, LI_FROM_INNERMOST) |
3a0ecac2 | 2277 | { |
e8eed2f8 | 2278 | curr_loop = loop; |
86482d6b | 2279 | /* move_single_loop_invariants for very large loops |
2280 | is time consuming and might need a lot of memory. */ | |
2281 | if (loop->num_nodes <= (unsigned) LOOP_INVARIANT_MAX_BBS_IN_LOOP) | |
2282 | move_single_loop_invariants (loop); | |
3a0ecac2 | 2283 | } |
2284 | ||
f21d4d00 | 2285 | FOR_EACH_LOOP (loop, 0) |
17519ba0 | 2286 | { |
2287 | free_loop_data (loop); | |
2288 | } | |
3a0ecac2 | 2289 | |
e8eed2f8 | 2290 | if (flag_ira_loop_pressure) |
2291 | /* There is no sense to keep this info because it was most | |
2292 | probably outdated by subsequent passes. */ | |
2293 | free_reg_info (); | |
3072d30e | 2294 | free (invariant_table); |
2295 | invariant_table = NULL; | |
2296 | invariant_table_size = 0; | |
2c5cdc40 | 2297 | |
9b316951 | 2298 | if (optimize == 1) |
2299 | df_remove_problem (df_live); | |
2300 | ||
382ecba7 | 2301 | checking_verify_flow_info (); |
3a0ecac2 | 2302 | } |