1 | /* Rematerialize pseudos values. |
2 | Copyright (C) 2014-2023 Free Software Foundation, Inc. |
3 | Contributed by Vladimir Makarov <vmakarov@redhat.com>. |
4 | |
5 | This file is part of GCC. |
6 | |
7 | GCC is free software; you can redistribute it and/or modify it under |
8 | the terms of the GNU General Public License as published by the Free |
9 | Software Foundation; either version 3, or (at your option) any later |
10 | version. |
11 | |
12 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
13 | WARRANTY; without even the implied warranty of MERCHANTABILITY or |
14 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
15 | for more details. |
16 | |
17 | You should have received a copy of the GNU General Public License |
18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ |
20 | |
21 | /* This code objective is to rematerialize spilled pseudo values. To |
22 | do this we calculate available insn candidates. The candidate is |
23 | available at some point if there is dominated set of insns with the |
24 | same pattern, the insn inputs are not dying or modified on any path |
25 | from the set, the outputs are not modified. |
26 | |
27 | The insns containing memory or spilled pseudos (except for the |
28 | rematerialized pseudo) are not considered as such insns are not |
29 | profitable in comparison with regular loads of spilled pseudo |
30 | values. That simplifies the implementation as we don't need to |
31 | deal with memory aliasing. |
32 | |
33 | To speed up available candidate calculation, we calculate partially |
34 | available candidates first and use them for initialization of the |
35 | availability. That is because (partial) availability sets are |
36 | sparse. |
37 | |
38 | The rematerialization sub-pass could be improved further in the |
39 | following ways: |
40 | |
41 | o We could make longer live ranges of inputs in the |
42 | rematerialization candidates if their hard registers are not used |
43 | for other purposes. This could be complicated if we need to |
44 | update BB live info information as LRA does not use |
45 | DF-infrastructure for compile-time reasons. This problem could |
46 | be overcome if constrain making live ranges longer only in BB/EBB |
47 | scope. |
48 | o We could use cost-based decision to choose rematerialization insn |
49 | (currently all insns without memory is can be used). |
50 | o We could use other free hard regs for unused output pseudos in |
51 | rematerialization candidates although such cases probably will |
52 | be very rare. */ |
53 | |
54 | |
55 | #include "config.h" |
56 | #include "system.h" |
57 | #include "coretypes.h" |
58 | #include "backend.h" |
59 | #include "rtl.h" |
60 | #include "df.h" |
61 | #include "insn-config.h" |
62 | #include "regs.h" |
63 | #include "memmodel.h" |
64 | #include "ira.h" |
65 | #include "recog.h" |
66 | #include "lra.h" |
67 | #include "lra-int.h" |
68 | #include "function-abi.h" |
69 | |
70 | /* Number of candidates for rematerialization. */ |
71 | static unsigned int cands_num; |
72 | |
73 | /* Bitmap used for different calculations. */ |
74 | static bitmap_head temp_bitmap; |
75 | |
76 | /* Registers accessed via subreg_p. */ |
77 | static bitmap_head subreg_regs; |
78 | |
79 | typedef struct cand *cand_t; |
80 | typedef const struct cand *const_cand_t; |
81 | |
82 | /* Insn candidates for rematerialization. The candidate insn should |
83 | have the following properies: |
84 | o no any memory (as access to memory is non-profitable) |
85 | o no INOUT regs (it means no non-paradoxical subreg of output reg) |
86 | o one output spilled pseudo (or reload pseudo of a spilled pseudo) |
87 | o all other pseudos are with assigned hard regs. */ |
88 | struct cand |
89 | { |
90 | /* Index of the candidates in all_cands. */ |
91 | int index; |
92 | /* Insn pseudo regno for rematerialization. */ |
93 | int regno; |
94 | /* The candidate insn. */ |
95 | rtx_insn *insn; |
96 | /* Non-negative if a reload pseudo is in the insn instead of the |
97 | pseudo for rematerialization. */ |
98 | int reload_regno; |
99 | /* Number of the operand containing the regno or its reload |
100 | regno. */ |
101 | int nop; |
102 | /* Next candidate for the same regno. */ |
103 | cand_t next_regno_cand; |
104 | }; |
105 | |
106 | /* Vector containing all candidates. */ |
107 | static vec<cand_t> all_cands; |
108 | /* Map: insn -> candidate representing it. It is null if the insn cannot |
109 | be used for rematerialization. */ |
110 | static cand_t *insn_to_cand; |
111 | /* A secondary map, for candidates that involve two insns, where the |
112 | second one makes the equivalence. The candidate must not be used |
113 | before seeing this activation insn. */ |
114 | static cand_t *insn_to_cand_activation; |
115 | |
116 | /* Map regno -> candidates can be used for the regno |
117 | rematerialization. */ |
118 | static cand_t *regno_cands; |
119 | |
120 | /* Data about basic blocks used for the rematerialization |
121 | sub-pass. */ |
122 | class remat_bb_data |
123 | { |
124 | public: |
125 | /* Basic block about which the below data are. */ |
126 | basic_block bb; |
127 | /* Registers changed in the basic block: */ |
128 | bitmap_head changed_regs; |
129 | /* Registers becoming dead in the BB. */ |
130 | bitmap_head dead_regs; |
131 | /* Cands present in the BB whose in/out regs are not changed after |
132 | the cands occurence and are not dead (except the reload |
133 | regno). */ |
134 | bitmap_head gen_cands; |
135 | bitmap_head livein_cands; /* cands whose inputs live at the BB start. */ |
136 | bitmap_head pavin_cands; /* cands partially available at BB entry. */ |
137 | bitmap_head pavout_cands; /* cands partially available at BB exit. */ |
138 | bitmap_head avin_cands; /* cands available at the entry of the BB. */ |
139 | bitmap_head avout_cands; /* cands available at the exit of the BB. */ |
140 | }; |
141 | |
142 | /* Array for all BB data. Indexed by the corresponding BB index. */ |
143 | typedef class remat_bb_data *remat_bb_data_t; |
144 | |
145 | /* Basic blocks for data flow problems -- all bocks except the special |
146 | ones. */ |
147 | static bitmap_head all_blocks; |
148 | |
149 | /* All basic block data are referred through the following array. */ |
150 | static remat_bb_data_t remat_bb_data; |
151 | |
152 | /* Two small functions for access to the bb data. */ |
153 | static inline remat_bb_data_t |
154 | get_remat_bb_data (basic_block bb) |
155 | { |
156 | return &remat_bb_data[(bb)->index]; |
157 | } |
158 | |
159 | static inline remat_bb_data_t |
160 | get_remat_bb_data_by_index (int index) |
161 | { |
162 | return &remat_bb_data[index]; |
163 | } |
164 | |
165 | |
166 | |
167 | /* Hash table for the candidates. Different insns (e.g. structurally |
168 | the same insns or even insns with different unused output regs) can |
169 | be represented by the same candidate in the table. */ |
170 | static htab_t cand_table; |
171 | |
172 | /* Hash function for candidate CAND. */ |
173 | static hashval_t |
174 | cand_hash (const void *cand) |
175 | { |
176 | const_cand_t c = (const_cand_t) cand; |
177 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn: c->insn); |
178 | struct lra_static_insn_data *static_id = id->insn_static_data; |
179 | int nops = static_id->n_operands; |
180 | hashval_t hash = 0; |
181 | |
182 | for (int i = 0; i < nops; i++) |
183 | if (i == c->nop) |
184 | hash = iterative_hash_object (c->regno, hash); |
185 | else if (static_id->operand[i].type == OP_IN) |
186 | hash = iterative_hash_object (*id->operand_loc[i], hash); |
187 | return hash; |
188 | } |
189 | |
190 | /* Equal function for candidates CAND1 and CAND2. They are equal if |
191 | the corresponding candidate insns have the same code, the same |
192 | regno for rematerialization, the same input operands. */ |
193 | static int |
194 | cand_eq_p (const void *cand1, const void *cand2) |
195 | { |
196 | const_cand_t c1 = (const_cand_t) cand1; |
197 | const_cand_t c2 = (const_cand_t) cand2; |
198 | lra_insn_recog_data_t id1 = lra_get_insn_recog_data (insn: c1->insn); |
199 | lra_insn_recog_data_t id2 = lra_get_insn_recog_data (insn: c2->insn); |
200 | struct lra_static_insn_data *static_id1 = id1->insn_static_data; |
201 | int nops = static_id1->n_operands; |
202 | |
203 | if (c1->regno != c2->regno |
204 | || INSN_CODE (c1->insn) < 0 |
205 | || INSN_CODE (c1->insn) != INSN_CODE (c2->insn)) |
206 | return false; |
207 | gcc_assert (c1->nop == c2->nop); |
208 | for (int i = 0; i < nops; i++) |
209 | if (i != c1->nop && static_id1->operand[i].type == OP_IN |
210 | && *id1->operand_loc[i] != *id2->operand_loc[i]) |
211 | return false; |
212 | return true; |
213 | } |
214 | |
215 | /* Insert candidate CAND into the table if it is not there yet. |
216 | Return candidate which is in the table. */ |
217 | static cand_t |
218 | insert_cand (cand_t cand) |
219 | { |
220 | void **entry_ptr; |
221 | |
222 | entry_ptr = htab_find_slot (cand_table, cand, INSERT); |
223 | if (*entry_ptr == NULL) |
224 | *entry_ptr = (void *) cand; |
225 | return (cand_t) *entry_ptr; |
226 | } |
227 | |
228 | /* Free candidate CAND memory. */ |
229 | static void |
230 | free_cand (void *cand) |
231 | { |
232 | free (ptr: cand); |
233 | } |
234 | |
235 | /* Initiate the candidate table. */ |
236 | static void |
237 | initiate_cand_table (void) |
238 | { |
239 | cand_table = htab_create (8000, cand_hash, cand_eq_p, |
240 | (htab_del) free_cand); |
241 | } |
242 | |
243 | /* Finish the candidate table. */ |
244 | static void |
245 | finish_cand_table (void) |
246 | { |
247 | htab_delete (cand_table); |
248 | } |
249 | |
250 | |
251 | |
252 | /* Return true if X contains memory or some UNSPEC. We cannot just |
253 | check insn operands as memory or unspec might be not an operand |
254 | itself but contain an operand. Insn with memory access is not |
255 | profitable for rematerialization. Rematerialization of UNSPEC |
256 | might result in wrong code generation as the UNPEC effect is |
257 | unknown (e.g. generating a label). */ |
258 | static bool |
259 | bad_for_rematerialization_p (rtx x) |
260 | { |
261 | int i, j; |
262 | const char *fmt; |
263 | enum rtx_code code; |
264 | |
265 | if (MEM_P (x) || GET_CODE (x) == UNSPEC || GET_CODE (x) == UNSPEC_VOLATILE) |
266 | return true; |
267 | code = GET_CODE (x); |
268 | fmt = GET_RTX_FORMAT (code); |
269 | for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) |
270 | { |
271 | if (fmt[i] == 'e') |
272 | { |
273 | if (bad_for_rematerialization_p (XEXP (x, i))) |
274 | return true; |
275 | } |
276 | else if (fmt[i] == 'E') |
277 | { |
278 | for (j = XVECLEN (x, i) - 1; j >= 0; j--) |
279 | if (bad_for_rematerialization_p (XVECEXP (x, i, j))) |
280 | return true; |
281 | } |
282 | } |
283 | return false; |
284 | } |
285 | |
286 | /* If INSN cannot be used for rematerialization, return negative |
287 | value. If INSN can be considered as a candidate for |
288 | rematerialization, return value which is the operand number of the |
289 | pseudo for which the insn can be used for rematerialization. Here |
290 | we consider the insns without any memory, spilled pseudo (except |
291 | for the rematerialization pseudo), or dying or unused regs. */ |
292 | static int |
293 | operand_to_remat (rtx_insn *insn) |
294 | { |
295 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn); |
296 | struct lra_static_insn_data *static_id = id->insn_static_data; |
297 | struct lra_insn_reg *reg, *found_reg = NULL; |
298 | |
299 | /* Don't rematerialize insns which can change PC. */ |
300 | if (JUMP_P (insn) || CALL_P (insn)) |
301 | return -1; |
302 | /* First find a pseudo which can be rematerialized. */ |
303 | for (reg = id->regs; reg != NULL; reg = reg->next) |
304 | { |
305 | /* True FRAME_POINTER_NEEDED might be because we cannot follow |
306 | changing sp offsets, e.g. alloca is used. If the insn contains |
307 | stack pointer in such case, we cannot rematerialize it as we |
308 | cannot know sp offset at a rematerialization place. */ |
309 | if (reg->regno == STACK_POINTER_REGNUM && frame_pointer_needed) |
310 | return -1; |
311 | else if (reg->type == OP_OUT && ! reg->subreg_p |
312 | && find_regno_note (insn, REG_UNUSED, reg->regno) == NULL) |
313 | { |
314 | /* We permits only one spilled reg. */ |
315 | if (found_reg != NULL) |
316 | return -1; |
317 | found_reg = reg; |
318 | } |
319 | /* IRA calculates conflicts separately for subregs of two words |
320 | pseudo. Even if the pseudo lives, e.g. one its subreg can be |
321 | used lately, another subreg hard register can be already used |
322 | for something else. In such case, it is not safe to |
323 | rematerialize the insn. */ |
324 | if (reg->regno >= FIRST_PSEUDO_REGISTER |
325 | && bitmap_bit_p (&subreg_regs, reg->regno)) |
326 | return -1; |
327 | |
328 | /* Don't allow hard registers to be rematerialized. */ |
329 | if (reg->regno < FIRST_PSEUDO_REGISTER) |
330 | return -1; |
331 | } |
332 | if (found_reg == NULL) |
333 | return -1; |
334 | if (found_reg->regno < FIRST_PSEUDO_REGISTER) |
335 | return -1; |
336 | if (bad_for_rematerialization_p (x: PATTERN (insn))) |
337 | return -1; |
338 | /* Check the other regs are not spilled. */ |
339 | for (reg = id->regs; reg != NULL; reg = reg->next) |
340 | if (found_reg == reg) |
341 | continue; |
342 | else if (reg->type == OP_INOUT) |
343 | return -1; |
344 | else if (reg->regno >= FIRST_PSEUDO_REGISTER |
345 | && reg_renumber[reg->regno] < 0) |
346 | /* Another spilled reg. */ |
347 | return -1; |
348 | else if (reg->type == OP_IN) |
349 | { |
350 | if (find_regno_note (insn, REG_DEAD, reg->regno) != NULL) |
351 | /* We don't want to make live ranges longer. */ |
352 | return -1; |
353 | /* Check that there is no output reg as the input one. */ |
354 | for (struct lra_insn_reg *reg2 = id->regs; |
355 | reg2 != NULL; |
356 | reg2 = reg2->next) |
357 | if (reg2->type == OP_OUT && reg->regno == reg2->regno) |
358 | return -1; |
359 | if (reg->regno < FIRST_PSEUDO_REGISTER) |
360 | for (struct lra_insn_reg *reg2 = static_id->hard_regs; |
361 | reg2 != NULL; |
362 | reg2 = reg2->next) |
363 | if (reg2->type == OP_OUT |
364 | && reg->regno <= reg2->regno |
365 | && (reg2->regno |
366 | < (int) end_hard_regno (mode: reg->biggest_mode, regno: reg->regno))) |
367 | return -1; |
368 | } |
369 | /* Check hard coded insn registers. */ |
370 | for (struct lra_insn_reg *reg = static_id->hard_regs; |
371 | reg != NULL; |
372 | reg = reg->next) |
373 | if (reg->type == OP_INOUT) |
374 | return -1; |
375 | else if (reg->type == OP_IN) |
376 | { |
377 | /* Check that there is no output hard reg as the input |
378 | one. */ |
379 | for (struct lra_insn_reg *reg2 = static_id->hard_regs; |
380 | reg2 != NULL; |
381 | reg2 = reg2->next) |
382 | if (reg2->type == OP_OUT && reg->regno == reg2->regno) |
383 | return -1; |
384 | } |
385 | /* Find the rematerialization operand. */ |
386 | int nop = static_id->n_operands; |
387 | for (int i = 0; i < nop; i++) |
388 | if (REG_P (*id->operand_loc[i]) |
389 | && (int) REGNO (*id->operand_loc[i]) == found_reg->regno) |
390 | return i; |
391 | return -1; |
392 | } |
393 | |
394 | /* Create candidate for INSN with rematerialization operand NOP and |
395 | REGNO. Insert the candidate into the table and set up the |
396 | corresponding INSN_TO_CAND element. */ |
397 | static void |
398 | create_cand (rtx_insn *insn, int nop, int regno, rtx_insn *activation = NULL) |
399 | { |
400 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn); |
401 | rtx reg = *id->operand_loc[nop]; |
402 | gcc_assert (REG_P (reg)); |
403 | int op_regno = REGNO (reg); |
404 | gcc_assert (op_regno >= FIRST_PSEUDO_REGISTER); |
405 | cand_t cand = XNEW (struct cand); |
406 | cand->insn = insn; |
407 | cand->nop = nop; |
408 | cand->regno = regno; |
409 | cand->reload_regno = op_regno == regno ? -1 : op_regno; |
410 | gcc_assert (cand->regno >= 0); |
411 | cand_t cand_in_table = insert_cand (cand); |
412 | insn_to_cand[INSN_UID (insn)] = cand_in_table; |
413 | if (cand != cand_in_table) |
414 | free (ptr: cand); |
415 | else |
416 | { |
417 | /* A new cand. */ |
418 | cand->index = all_cands.length (); |
419 | all_cands.safe_push (obj: cand); |
420 | cand->next_regno_cand = regno_cands[cand->regno]; |
421 | regno_cands[cand->regno] = cand; |
422 | } |
423 | if (activation) |
424 | insn_to_cand_activation[INSN_UID (insn: activation)] = cand_in_table; |
425 | } |
426 | |
427 | /* Create rematerialization candidates (inserting them into the |
428 | table). */ |
429 | static void |
430 | create_cands (void) |
431 | { |
432 | rtx_insn *insn; |
433 | struct potential_cand |
434 | { |
435 | rtx_insn *insn; |
436 | int nop; |
437 | }; |
438 | struct potential_cand *regno_potential_cand; |
439 | |
440 | /* Create candidates. */ |
441 | regno_potential_cand = XCNEWVEC (struct potential_cand, max_reg_num ()); |
442 | for (insn = get_insns (); insn; insn = NEXT_INSN (insn)) |
443 | if (NONDEBUG_INSN_P (insn)) |
444 | { |
445 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn); |
446 | int keep_regno = -1; |
447 | rtx set = single_set (insn); |
448 | int nop; |
449 | |
450 | /* See if this is an output reload for a previous insn. */ |
451 | if (set != NULL |
452 | && REG_P (SET_SRC (set)) && REG_P (SET_DEST (set))) |
453 | { |
454 | rtx dstreg = SET_DEST (set); |
455 | int src_regno = REGNO (SET_SRC (set)); |
456 | int dst_regno = REGNO (dstreg); |
457 | rtx_insn *insn2 = regno_potential_cand[src_regno].insn; |
458 | |
459 | if (insn2 != NULL |
460 | && dst_regno >= FIRST_PSEUDO_REGISTER |
461 | && reg_renumber[dst_regno] < 0 |
462 | && BLOCK_FOR_INSN (insn: insn2) == BLOCK_FOR_INSN (insn)) |
463 | { |
464 | create_cand (insn: insn2, nop: regno_potential_cand[src_regno].nop, |
465 | regno: dst_regno, activation: insn); |
466 | goto done; |
467 | } |
468 | } |
469 | |
470 | nop = operand_to_remat (insn); |
471 | if (nop >= 0) |
472 | { |
473 | gcc_assert (REG_P (*id->operand_loc[nop])); |
474 | int regno = REGNO (*id->operand_loc[nop]); |
475 | gcc_assert (regno >= FIRST_PSEUDO_REGISTER); |
476 | /* If we're setting an unrenumbered pseudo, make a candidate immediately. |
477 | If it's an output reload register, save it for later; the code above |
478 | looks for output reload insns later on. */ |
479 | if (reg_renumber[regno] < 0) |
480 | create_cand (insn, nop, regno); |
481 | else if (regno >= lra_constraint_new_regno_start) |
482 | { |
483 | regno_potential_cand[regno].insn = insn; |
484 | regno_potential_cand[regno].nop = nop; |
485 | keep_regno = regno; |
486 | } |
487 | } |
488 | |
489 | done: |
490 | for (struct lra_insn_reg *reg = id->regs; reg != NULL; reg = reg->next) |
491 | if (reg->type != OP_IN && reg->regno != keep_regno |
492 | && reg->regno >= FIRST_PSEUDO_REGISTER) |
493 | regno_potential_cand[reg->regno].insn = NULL; |
494 | } |
495 | cands_num = all_cands.length (); |
496 | free (ptr: regno_potential_cand); |
497 | } |
498 | |
499 | |
500 | |
501 | /* Create and initialize BB data. */ |
502 | static void |
503 | create_remat_bb_data (void) |
504 | { |
505 | basic_block bb; |
506 | remat_bb_data_t bb_info; |
507 | |
508 | remat_bb_data = XNEWVEC (class remat_bb_data, |
509 | last_basic_block_for_fn (cfun)); |
510 | FOR_ALL_BB_FN (bb, cfun) |
511 | { |
512 | gcc_checking_assert (bb->index >= 0 |
513 | && bb->index < last_basic_block_for_fn (cfun)); |
514 | bb_info = get_remat_bb_data (bb); |
515 | bb_info->bb = bb; |
516 | bitmap_initialize (head: &bb_info->changed_regs, obstack: ®_obstack); |
517 | bitmap_initialize (head: &bb_info->dead_regs, obstack: ®_obstack); |
518 | bitmap_initialize (head: &bb_info->gen_cands, obstack: ®_obstack); |
519 | bitmap_initialize (head: &bb_info->livein_cands, obstack: ®_obstack); |
520 | bitmap_initialize (head: &bb_info->pavin_cands, obstack: ®_obstack); |
521 | bitmap_initialize (head: &bb_info->pavout_cands, obstack: ®_obstack); |
522 | bitmap_initialize (head: &bb_info->avin_cands, obstack: ®_obstack); |
523 | bitmap_initialize (head: &bb_info->avout_cands, obstack: ®_obstack); |
524 | } |
525 | } |
526 | |
527 | /* Dump all candidates to DUMP_FILE. */ |
528 | static void |
529 | dump_cands (FILE *dump_file) |
530 | { |
531 | int i; |
532 | cand_t cand; |
533 | |
534 | fprintf (stream: dump_file, format: "\nCands:\n" ); |
535 | for (i = 0; i < (int) cands_num; i++) |
536 | { |
537 | cand = all_cands[i]; |
538 | fprintf (stream: dump_file, format: "%d (nop=%d, remat_regno=%d, reload_regno=%d):\n" , |
539 | i, cand->nop, cand->regno, cand->reload_regno); |
540 | print_inline_rtx (dump_file, cand->insn, 6); |
541 | fprintf (stream: dump_file, format: "\n" ); |
542 | } |
543 | } |
544 | |
545 | /* Dump all candidates and BB data. */ |
546 | static void |
547 | dump_candidates_and_remat_bb_data (void) |
548 | { |
549 | basic_block bb; |
550 | |
551 | if (lra_dump_file == NULL) |
552 | return; |
553 | dump_cands (dump_file: lra_dump_file); |
554 | FOR_EACH_BB_FN (bb, cfun) |
555 | { |
556 | fprintf (stream: lra_dump_file, format: "\nBB %d:\n" , bb->index); |
557 | /* Livein */ |
558 | fprintf (stream: lra_dump_file, format: " register live in:" ); |
559 | dump_regset (df_get_live_in (bb), lra_dump_file); |
560 | putc (c: '\n', stream: lra_dump_file); |
561 | /* Liveout */ |
562 | fprintf (stream: lra_dump_file, format: " register live out:" ); |
563 | dump_regset (df_get_live_out (bb), lra_dump_file); |
564 | putc (c: '\n', stream: lra_dump_file); |
565 | /* Changed/dead regs: */ |
566 | fprintf (stream: lra_dump_file, format: " changed regs:" ); |
567 | dump_regset (&get_remat_bb_data (bb)->changed_regs, lra_dump_file); |
568 | putc (c: '\n', stream: lra_dump_file); |
569 | fprintf (stream: lra_dump_file, format: " dead regs:" ); |
570 | dump_regset (&get_remat_bb_data (bb)->dead_regs, lra_dump_file); |
571 | putc (c: '\n', stream: lra_dump_file); |
572 | lra_dump_bitmap_with_title ("cands generated in BB" , |
573 | &get_remat_bb_data (bb)->gen_cands, bb->index); |
574 | lra_dump_bitmap_with_title ("livein cands in BB" , |
575 | &get_remat_bb_data (bb)->livein_cands, bb->index); |
576 | lra_dump_bitmap_with_title ("pavin cands in BB" , |
577 | &get_remat_bb_data (bb)->pavin_cands, bb->index); |
578 | lra_dump_bitmap_with_title ("pavout cands in BB" , |
579 | &get_remat_bb_data (bb)->pavout_cands, bb->index); |
580 | lra_dump_bitmap_with_title ("avin cands in BB" , |
581 | &get_remat_bb_data (bb)->avin_cands, bb->index); |
582 | lra_dump_bitmap_with_title ("avout cands in BB" , |
583 | &get_remat_bb_data (bb)->avout_cands, bb->index); |
584 | } |
585 | fprintf (stream: lra_dump_file, format: "subreg regs:" ); |
586 | dump_regset (&subreg_regs, lra_dump_file); |
587 | putc (c: '\n', stream: lra_dump_file); |
588 | } |
589 | |
590 | /* Free all BB data. */ |
591 | static void |
592 | finish_remat_bb_data (void) |
593 | { |
594 | basic_block bb; |
595 | |
596 | FOR_EACH_BB_FN (bb, cfun) |
597 | { |
598 | bitmap_clear (&get_remat_bb_data (bb)->avout_cands); |
599 | bitmap_clear (&get_remat_bb_data (bb)->avin_cands); |
600 | bitmap_clear (&get_remat_bb_data (bb)->pavout_cands); |
601 | bitmap_clear (&get_remat_bb_data (bb)->pavin_cands); |
602 | bitmap_clear (&get_remat_bb_data (bb)->livein_cands); |
603 | bitmap_clear (&get_remat_bb_data (bb)->gen_cands); |
604 | bitmap_clear (&get_remat_bb_data (bb)->dead_regs); |
605 | bitmap_clear (&get_remat_bb_data (bb)->changed_regs); |
606 | } |
607 | free (ptr: remat_bb_data); |
608 | } |
609 | |
610 | |
611 | |
612 | /* Update changed_regs, dead_regs, subreg_regs of BB from INSN. */ |
613 | static void |
614 | set_bb_regs (basic_block bb, rtx_insn *insn) |
615 | { |
616 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn); |
617 | remat_bb_data_t bb_info = get_remat_bb_data (bb); |
618 | struct lra_insn_reg *reg; |
619 | |
620 | for (reg = id->regs; reg != NULL; reg = reg->next) |
621 | { |
622 | unsigned regno = reg->regno; |
623 | if (reg->type != OP_IN) |
624 | bitmap_set_bit (&bb_info->changed_regs, regno); |
625 | else if (find_regno_note (insn, REG_DEAD, regno) != NULL) |
626 | bitmap_set_bit (&bb_info->dead_regs, regno); |
627 | if (regno >= FIRST_PSEUDO_REGISTER && reg->subreg_p) |
628 | bitmap_set_bit (&subreg_regs, regno); |
629 | } |
630 | if (CALL_P (insn)) |
631 | { |
632 | /* Partially-clobbered registers might still be live. */ |
633 | HARD_REG_SET clobbers = insn_callee_abi (insn).full_reg_clobbers (); |
634 | bitmap_ior_into (&get_remat_bb_data (bb)->dead_regs, |
635 | bitmap_view<HARD_REG_SET> (clobbers)); |
636 | } |
637 | } |
638 | |
639 | /* Calculate changed_regs and dead_regs for each BB. */ |
640 | static void |
641 | calculate_local_reg_remat_bb_data (void) |
642 | { |
643 | basic_block bb; |
644 | rtx_insn *insn; |
645 | |
646 | FOR_EACH_BB_FN (bb, cfun) |
647 | FOR_BB_INSNS (bb, insn) |
648 | if (NONDEBUG_INSN_P (insn)) |
649 | set_bb_regs (bb, insn); |
650 | } |
651 | |
652 | |
653 | |
654 | /* Return true if REG overlaps an input operand or non-input hard register of |
655 | INSN. Basically the function returns false if we can move rematerialization |
656 | candidate INSN through another insn with output REG or dead input REG (we |
657 | consider it to avoid extending reg live range) with possible output pseudo |
658 | renaming in INSN. */ |
659 | static bool |
660 | reg_overlap_for_remat_p (lra_insn_reg *reg, rtx_insn *insn) |
661 | { |
662 | int iter; |
663 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn); |
664 | struct lra_static_insn_data *static_id = id->insn_static_data; |
665 | unsigned regno = reg->regno; |
666 | int nregs; |
667 | |
668 | if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] >= 0) |
669 | regno = reg_renumber[regno]; |
670 | if (regno >= FIRST_PSEUDO_REGISTER) |
671 | nregs = 1; |
672 | else |
673 | nregs = hard_regno_nregs (regno, mode: reg->biggest_mode); |
674 | |
675 | struct lra_insn_reg *reg2; |
676 | |
677 | for (iter = 0; iter < 2; iter++) |
678 | for (reg2 = (iter == 0 ? id->regs : static_id->hard_regs); |
679 | reg2 != NULL; |
680 | reg2 = reg2->next) |
681 | { |
682 | int nregs2; |
683 | unsigned regno2 = reg2->regno; |
684 | |
685 | if (reg2->type != OP_IN && regno2 >= FIRST_PSEUDO_REGISTER) |
686 | continue; |
687 | |
688 | if (regno2 >= FIRST_PSEUDO_REGISTER && reg_renumber[regno2] >= 0) |
689 | regno2 = reg_renumber[regno2]; |
690 | if (regno2 >= FIRST_PSEUDO_REGISTER) |
691 | nregs2 = 1; |
692 | else |
693 | nregs2 = hard_regno_nregs (regno: regno2, mode: reg->biggest_mode); |
694 | |
695 | if ((regno2 + nregs2 - 1 >= regno && regno2 < regno + nregs) |
696 | || (regno + nregs - 1 >= regno2 && regno < regno2 + nregs2)) |
697 | return true; |
698 | } |
699 | return false; |
700 | } |
701 | |
702 | /* Return true if a call used register is an input operand of INSN. */ |
703 | static bool |
704 | call_used_input_regno_present_p (const function_abi &abi, rtx_insn *insn) |
705 | { |
706 | int iter; |
707 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn); |
708 | struct lra_static_insn_data *static_id = id->insn_static_data; |
709 | struct lra_insn_reg *reg; |
710 | |
711 | for (iter = 0; iter < 2; iter++) |
712 | for (reg = (iter == 0 ? id->regs : static_id->hard_regs); |
713 | reg != NULL; |
714 | reg = reg->next) |
715 | if (reg->type == OP_IN |
716 | && reg->regno < FIRST_PSEUDO_REGISTER |
717 | && abi.clobbers_reg_p (mode: reg->biggest_mode, regno: reg->regno)) |
718 | return true; |
719 | return false; |
720 | } |
721 | |
722 | /* Calculate livein_cands for each BB. */ |
723 | static void |
724 | calculate_livein_cands (void) |
725 | { |
726 | basic_block bb; |
727 | |
728 | FOR_EACH_BB_FN (bb, cfun) |
729 | { |
730 | bitmap livein_regs = df_get_live_in (bb); |
731 | bitmap livein_cands = &get_remat_bb_data (bb)->livein_cands; |
732 | for (unsigned int i = 0; i < cands_num; i++) |
733 | { |
734 | cand_t cand = all_cands[i]; |
735 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn: cand->insn); |
736 | struct lra_insn_reg *reg; |
737 | |
738 | for (reg = id->regs; reg != NULL; reg = reg->next) |
739 | if (reg->type == OP_IN && ! bitmap_bit_p (livein_regs, reg->regno)) |
740 | break; |
741 | if (reg == NULL) |
742 | bitmap_set_bit (livein_cands, i); |
743 | } |
744 | } |
745 | } |
746 | |
747 | /* Calculate gen_cands for each BB. */ |
748 | static void |
749 | calculate_gen_cands (void) |
750 | { |
751 | basic_block bb; |
752 | bitmap gen_cands; |
753 | rtx_insn *insn; |
754 | |
755 | FOR_EACH_BB_FN (bb, cfun) |
756 | { |
757 | gen_cands = &get_remat_bb_data (bb)->gen_cands; |
758 | auto_bitmap gen_insns (®_obstack); |
759 | FOR_BB_INSNS (bb, insn) |
760 | if (INSN_P (insn)) |
761 | { |
762 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn); |
763 | struct lra_static_insn_data *static_id = id->insn_static_data; |
764 | struct lra_insn_reg *reg; |
765 | unsigned int uid; |
766 | bitmap_iterator bi; |
767 | cand_t cand; |
768 | rtx set; |
769 | int iter; |
770 | int src_regno = -1, dst_regno = -1; |
771 | |
772 | if ((set = single_set (insn)) != NULL |
773 | && REG_P (SET_SRC (set)) && REG_P (SET_DEST (set))) |
774 | { |
775 | src_regno = REGNO (SET_SRC (set)); |
776 | dst_regno = REGNO (SET_DEST (set)); |
777 | } |
778 | |
779 | /* Update gen_cands: */ |
780 | bitmap_clear (&temp_bitmap); |
781 | for (iter = 0; iter < 2; iter++) |
782 | for (reg = (iter == 0 ? id->regs : static_id->hard_regs); |
783 | reg != NULL; |
784 | reg = reg->next) |
785 | if (reg->type != OP_IN |
786 | || find_regno_note (insn, REG_DEAD, reg->regno) != NULL) |
787 | EXECUTE_IF_SET_IN_BITMAP (gen_insns, 0, uid, bi) |
788 | { |
789 | rtx_insn *insn2 = lra_insn_recog_data[uid]->insn; |
790 | |
791 | cand = insn_to_cand[INSN_UID (insn: insn2)]; |
792 | gcc_assert (cand != NULL); |
793 | /* Ignore the reload insn. */ |
794 | if (src_regno == cand->reload_regno |
795 | && dst_regno == cand->regno) |
796 | continue; |
797 | if (cand->regno == reg->regno |
798 | || reg_overlap_for_remat_p (reg, insn: insn2)) |
799 | { |
800 | bitmap_clear_bit (gen_cands, cand->index); |
801 | bitmap_set_bit (&temp_bitmap, uid); |
802 | } |
803 | } |
804 | |
805 | if (CALL_P (insn)) |
806 | { |
807 | function_abi callee_abi = insn_callee_abi (insn); |
808 | EXECUTE_IF_SET_IN_BITMAP (gen_insns, 0, uid, bi) |
809 | { |
810 | rtx_insn *insn2 = lra_insn_recog_data[uid]->insn; |
811 | |
812 | cand = insn_to_cand[INSN_UID (insn: insn2)]; |
813 | gcc_assert (cand != NULL); |
814 | if (call_used_input_regno_present_p (abi: callee_abi, insn: insn2)) |
815 | { |
816 | bitmap_clear_bit (gen_cands, cand->index); |
817 | bitmap_set_bit (&temp_bitmap, uid); |
818 | } |
819 | } |
820 | } |
821 | bitmap_and_compl_into (gen_insns, &temp_bitmap); |
822 | |
823 | cand = insn_to_cand[INSN_UID (insn)]; |
824 | if (cand != NULL) |
825 | { |
826 | bitmap_set_bit (gen_cands, cand->index); |
827 | bitmap_set_bit (gen_insns, INSN_UID (insn)); |
828 | } |
829 | } |
830 | } |
831 | } |
832 | |
833 | |
834 | |
835 | /* The common transfer function used by the DF equation solver to |
836 | propagate (partial) availability info BB_IN to BB_OUT through block |
837 | with BB_INDEX according to the following equation: |
838 | |
839 | bb.out = ((bb.in & bb.livein) - bb.killed) OR bb.gen |
840 | */ |
841 | static bool |
842 | cand_trans_fun (int bb_index, bitmap bb_in, bitmap bb_out) |
843 | { |
844 | remat_bb_data_t bb_info; |
845 | bitmap bb_livein, bb_changed_regs, bb_dead_regs; |
846 | unsigned int cid; |
847 | bitmap_iterator bi; |
848 | |
849 | bb_info = get_remat_bb_data_by_index (index: bb_index); |
850 | bb_livein = &bb_info->livein_cands; |
851 | bb_changed_regs = &bb_info->changed_regs; |
852 | bb_dead_regs = &bb_info->dead_regs; |
853 | /* Calculate killed avin cands -- cands whose regs are changed or |
854 | becoming dead in the BB. We calculate it here as we hope that |
855 | repeated calculations are compensated by smaller size of BB_IN in |
856 | comparison with all candidates number. */ |
857 | bitmap_clear (&temp_bitmap); |
858 | EXECUTE_IF_SET_IN_BITMAP (bb_in, 0, cid, bi) |
859 | { |
860 | cand_t cand = all_cands[cid]; |
861 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn: cand->insn); |
862 | struct lra_insn_reg *reg; |
863 | |
864 | if (! bitmap_bit_p (bb_livein, cid)) |
865 | { |
866 | bitmap_set_bit (&temp_bitmap, cid); |
867 | continue; |
868 | } |
869 | for (reg = id->regs; reg != NULL; reg = reg->next) |
870 | /* Ignore all outputs which are not the regno for |
871 | rematerialization. */ |
872 | if (reg->type == OP_OUT && reg->regno != cand->regno) |
873 | continue; |
874 | else if (bitmap_bit_p (bb_changed_regs, reg->regno) |
875 | || bitmap_bit_p (bb_dead_regs, reg->regno)) |
876 | { |
877 | bitmap_set_bit (&temp_bitmap, cid); |
878 | break; |
879 | } |
880 | /* Check regno for rematerialization. */ |
881 | if (bitmap_bit_p (bb_changed_regs, cand->regno) |
882 | || bitmap_bit_p (bb_dead_regs, cand->regno)) |
883 | bitmap_set_bit (&temp_bitmap, cid); |
884 | } |
885 | return bitmap_ior_and_compl (DST: bb_out, |
886 | A: &bb_info->gen_cands, B: bb_in, C: &temp_bitmap); |
887 | } |
888 | |
889 | |
890 | |
891 | /* The transfer function used by the DF equation solver to propagate |
892 | partial candidate availability info through block with BB_INDEX |
893 | according to the following equation: |
894 | |
895 | bb.pavout = ((bb.pavin & bb.livein) - bb.killed) OR bb.gen |
896 | */ |
897 | static bool |
898 | cand_pav_trans_fun (int bb_index) |
899 | { |
900 | remat_bb_data_t bb_info; |
901 | |
902 | bb_info = get_remat_bb_data_by_index (index: bb_index); |
903 | return cand_trans_fun (bb_index, bb_in: &bb_info->pavin_cands, |
904 | bb_out: &bb_info->pavout_cands); |
905 | } |
906 | |
907 | /* The confluence function used by the DF equation solver to set up |
908 | cand_pav info for a block BB without predecessor. */ |
909 | static void |
910 | cand_pav_con_fun_0 (basic_block bb) |
911 | { |
912 | bitmap_clear (&get_remat_bb_data (bb)->pavin_cands); |
913 | } |
914 | |
915 | /* The confluence function used by the DF equation solver to propagate |
916 | partial candidate availability info from predecessor to successor |
917 | on edge E (pred->bb) according to the following equation: |
918 | |
919 | bb.pavin_cands = 0 for entry block | OR (pavout_cands of predecessors) |
920 | */ |
921 | static bool |
922 | cand_pav_con_fun_n (edge e) |
923 | { |
924 | basic_block pred = e->src; |
925 | basic_block bb = e->dest; |
926 | remat_bb_data_t bb_info; |
927 | bitmap bb_pavin, pred_pavout; |
928 | |
929 | bb_info = get_remat_bb_data (bb); |
930 | bb_pavin = &bb_info->pavin_cands; |
931 | pred_pavout = &get_remat_bb_data (bb: pred)->pavout_cands; |
932 | return bitmap_ior_into (bb_pavin, pred_pavout); |
933 | } |
934 | |
935 | |
936 | |
937 | /* The transfer function used by the DF equation solver to propagate |
938 | candidate availability info through block with BB_INDEX according |
939 | to the following equation: |
940 | |
941 | bb.avout = ((bb.avin & bb.livein) - bb.killed) OR bb.gen |
942 | */ |
943 | static bool |
944 | cand_av_trans_fun (int bb_index) |
945 | { |
946 | remat_bb_data_t bb_info; |
947 | |
948 | bb_info = get_remat_bb_data_by_index (index: bb_index); |
949 | return cand_trans_fun (bb_index, bb_in: &bb_info->avin_cands, |
950 | bb_out: &bb_info->avout_cands); |
951 | } |
952 | |
953 | /* The confluence function used by the DF equation solver to set up |
954 | cand_av info for a block BB without predecessor. */ |
955 | static void |
956 | cand_av_con_fun_0 (basic_block bb) |
957 | { |
958 | bitmap_clear (&get_remat_bb_data (bb)->avin_cands); |
959 | } |
960 | |
961 | /* The confluence function used by the DF equation solver to propagate |
962 | cand_av info from predecessor to successor on edge E (pred->bb) |
963 | according to the following equation: |
964 | |
965 | bb.avin_cands = 0 for entry block | AND (avout_cands of predecessors) |
966 | */ |
967 | static bool |
968 | cand_av_con_fun_n (edge e) |
969 | { |
970 | basic_block pred = e->src; |
971 | basic_block bb = e->dest; |
972 | remat_bb_data_t bb_info; |
973 | bitmap bb_avin, pred_avout; |
974 | |
975 | bb_info = get_remat_bb_data (bb); |
976 | bb_avin = &bb_info->avin_cands; |
977 | pred_avout = &get_remat_bb_data (bb: pred)->avout_cands; |
978 | return bitmap_and_into (bb_avin, pred_avout); |
979 | } |
980 | |
981 | /* Calculate available candidates for each BB. */ |
982 | static void |
983 | calculate_global_remat_bb_data (void) |
984 | { |
985 | basic_block bb; |
986 | |
987 | df_simple_dataflow |
988 | (DF_FORWARD, NULL, cand_pav_con_fun_0, cand_pav_con_fun_n, |
989 | cand_pav_trans_fun, &all_blocks, |
990 | df_get_postorder (DF_FORWARD), df_get_n_blocks (DF_FORWARD)); |
991 | /* Initialize avin by pavin. */ |
992 | FOR_EACH_BB_FN (bb, cfun) |
993 | bitmap_copy (&get_remat_bb_data (bb)->avin_cands, |
994 | &get_remat_bb_data (bb)->pavin_cands); |
995 | df_simple_dataflow |
996 | (DF_FORWARD, NULL, cand_av_con_fun_0, cand_av_con_fun_n, |
997 | cand_av_trans_fun, &all_blocks, |
998 | df_get_postorder (DF_FORWARD), df_get_n_blocks (DF_FORWARD)); |
999 | } |
1000 | |
1001 | |
1002 | |
1003 | /* Setup sp offset attribute to SP_OFFSET for all INSNS. */ |
1004 | static void |
1005 | change_sp_offset (rtx_insn *insns, poly_int64 sp_offset) |
1006 | { |
1007 | for (rtx_insn *insn = insns; insn != NULL; insn = NEXT_INSN (insn)) |
1008 | eliminate_regs_in_insn (insn, false, false, sp_offset); |
1009 | } |
1010 | |
1011 | /* Return start hard register of REG (can be a hard or a pseudo reg) |
1012 | or -1 (if it is a spilled pseudo). Return number of hard registers |
1013 | occupied by REG through parameter NREGS if the start hard reg is |
1014 | not negative. */ |
1015 | static int |
1016 | get_hard_regs (struct lra_insn_reg *reg, int &nregs) |
1017 | { |
1018 | int regno = reg->regno; |
1019 | int hard_regno = regno < FIRST_PSEUDO_REGISTER ? regno : reg_renumber[regno]; |
1020 | |
1021 | if (hard_regno >= 0) |
1022 | nregs = hard_regno_nregs (regno: hard_regno, mode: reg->biggest_mode); |
1023 | return hard_regno; |
1024 | } |
1025 | |
1026 | /* Make copy of and register scratch pseudos in rematerialized insn |
1027 | REMAT_INSN. */ |
1028 | static void |
1029 | update_scratch_ops (rtx_insn *remat_insn) |
1030 | { |
1031 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn: remat_insn); |
1032 | struct lra_static_insn_data *static_id = id->insn_static_data; |
1033 | for (int i = 0; i < static_id->n_operands; i++) |
1034 | { |
1035 | rtx *loc = id->operand_loc[i]; |
1036 | if (! REG_P (*loc)) |
1037 | continue; |
1038 | int regno = REGNO (*loc); |
1039 | if (! ira_former_scratch_p (regno)) |
1040 | continue; |
1041 | *loc = lra_create_new_reg (GET_MODE (*loc), *loc, |
1042 | lra_get_allocno_class (regno), NULL, |
1043 | "scratch pseudo copy" ); |
1044 | ira_register_new_scratch_op (insn: remat_insn, nop: i, icode: id->icode); |
1045 | } |
1046 | |
1047 | } |
1048 | |
1049 | /* Insert rematerialization insns using the data-flow data calculated |
1050 | earlier. */ |
1051 | static bool |
1052 | do_remat (void) |
1053 | { |
1054 | unsigned regno; |
1055 | rtx_insn *insn; |
1056 | basic_block bb; |
1057 | bool changed_p = false; |
1058 | /* Living hard regs and hard registers of living pseudos. */ |
1059 | HARD_REG_SET live_hard_regs; |
1060 | bitmap_iterator bi; |
1061 | |
1062 | auto_bitmap avail_cands (®_obstack); |
1063 | auto_bitmap active_cands (®_obstack); |
1064 | FOR_EACH_BB_FN (bb, cfun) |
1065 | { |
1066 | CLEAR_HARD_REG_SET (set&: live_hard_regs); |
1067 | EXECUTE_IF_SET_IN_BITMAP (df_get_live_in (bb), 0, regno, bi) |
1068 | { |
1069 | int hard_regno = regno < FIRST_PSEUDO_REGISTER |
1070 | ? regno |
1071 | : reg_renumber[regno]; |
1072 | if (hard_regno >= 0) |
1073 | SET_HARD_REG_BIT (set&: live_hard_regs, bit: hard_regno); |
1074 | } |
1075 | bitmap_and (avail_cands, &get_remat_bb_data (bb)->avin_cands, |
1076 | &get_remat_bb_data (bb)->livein_cands); |
1077 | /* Activating insns are always in the same block as their corresponding |
1078 | remat insn, so at the start of a block the two bitsets are equal. */ |
1079 | bitmap_copy (active_cands, avail_cands); |
1080 | FOR_BB_INSNS (bb, insn) |
1081 | { |
1082 | if (!NONDEBUG_INSN_P (insn)) |
1083 | continue; |
1084 | |
1085 | lra_insn_recog_data_t id = lra_get_insn_recog_data (insn); |
1086 | struct lra_static_insn_data *static_id = id->insn_static_data; |
1087 | struct lra_insn_reg *reg; |
1088 | cand_t cand; |
1089 | unsigned int cid; |
1090 | bitmap_iterator bi; |
1091 | rtx set; |
1092 | int iter; |
1093 | int src_regno = -1, dst_regno = -1; |
1094 | |
1095 | if ((set = single_set (insn)) != NULL |
1096 | && REG_P (SET_SRC (set)) && REG_P (SET_DEST (set))) |
1097 | { |
1098 | src_regno = REGNO (SET_SRC (set)); |
1099 | dst_regno = REGNO (SET_DEST (set)); |
1100 | } |
1101 | |
1102 | cand = NULL; |
1103 | /* Check possibility of rematerialization (hard reg or |
1104 | unpsilled pseudo <- spilled pseudo): */ |
1105 | if (dst_regno >= 0 && src_regno >= FIRST_PSEUDO_REGISTER |
1106 | && reg_renumber[src_regno] < 0 |
1107 | && (dst_regno < FIRST_PSEUDO_REGISTER |
1108 | || reg_renumber[dst_regno] >= 0)) |
1109 | { |
1110 | for (cand = regno_cands[src_regno]; |
1111 | cand != NULL; |
1112 | cand = cand->next_regno_cand) |
1113 | if (bitmap_bit_p (avail_cands, cand->index) |
1114 | && bitmap_bit_p (active_cands, cand->index)) |
1115 | break; |
1116 | } |
1117 | int i, hard_regno, nregs; |
1118 | int dst_hard_regno, dst_nregs; |
1119 | rtx_insn *remat_insn = NULL; |
1120 | poly_int64 cand_sp_offset = 0; |
1121 | if (cand != NULL) |
1122 | { |
1123 | lra_insn_recog_data_t cand_id |
1124 | = lra_get_insn_recog_data (insn: cand->insn); |
1125 | struct lra_static_insn_data *static_cand_id |
1126 | = cand_id->insn_static_data; |
1127 | rtx saved_op = *cand_id->operand_loc[cand->nop]; |
1128 | |
1129 | /* Check clobbers do not kill something living. */ |
1130 | gcc_assert (REG_P (saved_op)); |
1131 | int ignore_regno = REGNO (saved_op); |
1132 | |
1133 | dst_hard_regno = dst_regno < FIRST_PSEUDO_REGISTER |
1134 | ? dst_regno : reg_renumber[dst_regno]; |
1135 | gcc_assert (dst_hard_regno >= 0); |
1136 | machine_mode mode = GET_MODE (SET_DEST (set)); |
1137 | dst_nregs = hard_regno_nregs (regno: dst_hard_regno, mode); |
1138 | |
1139 | for (reg = cand_id->regs; reg != NULL; reg = reg->next) |
1140 | if (reg->type != OP_IN && reg->regno != ignore_regno) |
1141 | { |
1142 | hard_regno = get_hard_regs (reg, nregs); |
1143 | gcc_assert (hard_regno >= 0); |
1144 | for (i = 0; i < nregs; i++) |
1145 | if (TEST_HARD_REG_BIT (set: live_hard_regs, bit: hard_regno + i)) |
1146 | break; |
1147 | if (i < nregs) |
1148 | break; |
1149 | /* Ensure the clobber also doesn't overlap dst_regno. */ |
1150 | if (hard_regno + nregs > dst_hard_regno |
1151 | && hard_regno < dst_hard_regno + dst_nregs) |
1152 | break; |
1153 | } |
1154 | |
1155 | if (reg == NULL) |
1156 | { |
1157 | for (reg = static_cand_id->hard_regs; |
1158 | reg != NULL; |
1159 | reg = reg->next) |
1160 | if (reg->type != OP_IN) |
1161 | { |
1162 | if (TEST_HARD_REG_BIT (set: live_hard_regs, bit: reg->regno)) |
1163 | break; |
1164 | if (reg->regno >= dst_hard_regno |
1165 | && reg->regno < dst_hard_regno + dst_nregs) |
1166 | break; |
1167 | } |
1168 | } |
1169 | |
1170 | if (reg == NULL) |
1171 | { |
1172 | *cand_id->operand_loc[cand->nop] = SET_DEST (set); |
1173 | lra_update_insn_regno_info (cand->insn); |
1174 | bool ok_p = lra_constrain_insn (cand->insn); |
1175 | if (ok_p) |
1176 | { |
1177 | rtx remat_pat = copy_insn (PATTERN (insn: cand->insn)); |
1178 | |
1179 | start_sequence (); |
1180 | emit_insn (remat_pat); |
1181 | remat_insn = get_insns (); |
1182 | end_sequence (); |
1183 | if (recog_memoized (insn: remat_insn) < 0) |
1184 | remat_insn = NULL; |
1185 | cand_sp_offset = cand_id->sp_offset; |
1186 | } |
1187 | *cand_id->operand_loc[cand->nop] = saved_op; |
1188 | lra_update_insn_regno_info (cand->insn); |
1189 | } |
1190 | } |
1191 | |
1192 | bitmap_clear (&temp_bitmap); |
1193 | /* Update avail_cands (see analogous code for |
1194 | calculate_gen_cands). */ |
1195 | for (iter = 0; iter < 2; iter++) |
1196 | for (reg = (iter == 0 ? id->regs : static_id->hard_regs); |
1197 | reg != NULL; |
1198 | reg = reg->next) |
1199 | if (reg->type != OP_IN |
1200 | || find_regno_note (insn, REG_DEAD, reg->regno) != NULL) |
1201 | EXECUTE_IF_SET_IN_BITMAP (avail_cands, 0, cid, bi) |
1202 | { |
1203 | cand = all_cands[cid]; |
1204 | |
1205 | /* Ignore the reload insn. */ |
1206 | if (src_regno == cand->reload_regno |
1207 | && dst_regno == cand->regno) |
1208 | continue; |
1209 | if (cand->regno == reg->regno |
1210 | || reg_overlap_for_remat_p (reg, insn: cand->insn)) |
1211 | bitmap_set_bit (&temp_bitmap, cand->index); |
1212 | } |
1213 | |
1214 | if (CALL_P (insn)) |
1215 | { |
1216 | function_abi callee_abi = insn_callee_abi (insn); |
1217 | EXECUTE_IF_SET_IN_BITMAP (avail_cands, 0, cid, bi) |
1218 | { |
1219 | cand = all_cands[cid]; |
1220 | |
1221 | if (call_used_input_regno_present_p (abi: callee_abi, insn: cand->insn)) |
1222 | bitmap_set_bit (&temp_bitmap, cand->index); |
1223 | } |
1224 | } |
1225 | |
1226 | bitmap_and_compl_into (avail_cands, &temp_bitmap); |
1227 | |
1228 | /* Now see whether a candidate is made active or available |
1229 | by this insn. */ |
1230 | cand = insn_to_cand_activation[INSN_UID (insn)]; |
1231 | if (cand) |
1232 | bitmap_set_bit (active_cands, cand->index); |
1233 | |
1234 | cand = insn_to_cand[INSN_UID (insn)]; |
1235 | if (cand != NULL) |
1236 | { |
1237 | bitmap_set_bit (avail_cands, cand->index); |
1238 | if (cand->reload_regno == -1) |
1239 | bitmap_set_bit (active_cands, cand->index); |
1240 | else |
1241 | bitmap_clear_bit (active_cands, cand->index); |
1242 | } |
1243 | |
1244 | if (remat_insn != NULL) |
1245 | { |
1246 | poly_int64 sp_offset_change = cand_sp_offset - id->sp_offset; |
1247 | if (maybe_ne (a: sp_offset_change, b: 0)) |
1248 | change_sp_offset (insns: remat_insn, sp_offset: sp_offset_change); |
1249 | update_scratch_ops (remat_insn); |
1250 | lra_process_new_insns (insn, remat_insn, NULL, |
1251 | "Inserting rematerialization insn" ); |
1252 | lra_set_insn_deleted (insn); |
1253 | changed_p = true; |
1254 | continue; |
1255 | } |
1256 | |
1257 | /* Update live hard regs: */ |
1258 | for (reg = id->regs; reg != NULL; reg = reg->next) |
1259 | if (reg->type == OP_IN |
1260 | && find_regno_note (insn, REG_DEAD, reg->regno) != NULL) |
1261 | { |
1262 | if ((hard_regno = get_hard_regs (reg, nregs)) < 0) |
1263 | continue; |
1264 | for (i = 0; i < nregs; i++) |
1265 | CLEAR_HARD_REG_BIT (set&: live_hard_regs, bit: hard_regno + i); |
1266 | } |
1267 | /* Process also hard regs (e.g. CC register) which are part |
1268 | of insn definition. */ |
1269 | for (reg = static_id->hard_regs; reg != NULL; reg = reg->next) |
1270 | if (reg->type == OP_IN |
1271 | && find_regno_note (insn, REG_DEAD, reg->regno) != NULL) |
1272 | CLEAR_HARD_REG_BIT (set&: live_hard_regs, bit: reg->regno); |
1273 | /* Inputs have been processed, now process outputs. */ |
1274 | for (reg = id->regs; reg != NULL; reg = reg->next) |
1275 | if (reg->type != OP_IN |
1276 | && find_regno_note (insn, REG_UNUSED, reg->regno) == NULL) |
1277 | { |
1278 | if ((hard_regno = get_hard_regs (reg, nregs)) < 0) |
1279 | continue; |
1280 | for (i = 0; i < nregs; i++) |
1281 | SET_HARD_REG_BIT (set&: live_hard_regs, bit: hard_regno + i); |
1282 | } |
1283 | for (reg = static_id->hard_regs; reg != NULL; reg = reg->next) |
1284 | if (reg->type != OP_IN |
1285 | && find_regno_note (insn, REG_UNUSED, reg->regno) == NULL) |
1286 | SET_HARD_REG_BIT (set&: live_hard_regs, bit: reg->regno); |
1287 | } |
1288 | } |
1289 | return changed_p; |
1290 | } |
1291 | |
1292 | |
1293 | |
1294 | /* Current number of rematerialization iteration. */ |
1295 | int lra_rematerialization_iter; |
1296 | |
1297 | /* Entry point of the rematerialization sub-pass. Return true if we |
1298 | did any rematerialization. */ |
1299 | bool |
1300 | lra_remat (void) |
1301 | { |
1302 | basic_block bb; |
1303 | bool result; |
1304 | int max_regno = max_reg_num (); |
1305 | |
1306 | if (! flag_lra_remat) |
1307 | return false; |
1308 | lra_rematerialization_iter++; |
1309 | if (lra_rematerialization_iter > LRA_MAX_REMATERIALIZATION_PASSES) |
1310 | return false; |
1311 | if (lra_dump_file != NULL) |
1312 | fprintf (stream: lra_dump_file, |
1313 | format: "\n******** Rematerialization #%d: ********\n\n" , |
1314 | lra_rematerialization_iter); |
1315 | timevar_push (tv: TV_LRA_REMAT); |
1316 | insn_to_cand = XCNEWVEC (cand_t, get_max_uid ()); |
1317 | insn_to_cand_activation = XCNEWVEC (cand_t, get_max_uid ()); |
1318 | regno_cands = XCNEWVEC (cand_t, max_regno); |
1319 | all_cands.create (nelems: 8000); |
1320 | initiate_cand_table (); |
1321 | create_remat_bb_data (); |
1322 | bitmap_initialize (head: &temp_bitmap, obstack: ®_obstack); |
1323 | bitmap_initialize (head: &subreg_regs, obstack: ®_obstack); |
1324 | calculate_local_reg_remat_bb_data (); |
1325 | create_cands (); |
1326 | calculate_livein_cands (); |
1327 | calculate_gen_cands (); |
1328 | bitmap_initialize (head: &all_blocks, obstack: ®_obstack); |
1329 | FOR_ALL_BB_FN (bb, cfun) |
1330 | bitmap_set_bit (&all_blocks, bb->index); |
1331 | calculate_global_remat_bb_data (); |
1332 | dump_candidates_and_remat_bb_data (); |
1333 | result = do_remat (); |
1334 | all_cands.release (); |
1335 | bitmap_clear (&temp_bitmap); |
1336 | bitmap_clear (&subreg_regs); |
1337 | finish_remat_bb_data (); |
1338 | finish_cand_table (); |
1339 | bitmap_clear (&all_blocks); |
1340 | free (ptr: regno_cands); |
1341 | free (ptr: insn_to_cand); |
1342 | free (ptr: insn_to_cand_activation); |
1343 | timevar_pop (tv: TV_LRA_REMAT); |
1344 | return result; |
1345 | } |
1346 | |