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c6a6cdaa | 1 | /* Build live ranges for pseudos. |
711789cc | 2 | Copyright (C) 2010-2013 Free Software Foundation, Inc. |
c6a6cdaa | 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 | ||
22 | /* This file contains code to build pseudo live-ranges (analogous | |
23 | structures used in IRA, so read comments about the live-ranges | |
24 | there) and other info necessary for other passes to assign | |
25 | hard-registers to pseudos, coalesce the spilled pseudos, and assign | |
26 | stack memory slots to spilled pseudos. */ | |
27 | ||
28 | #include "config.h" | |
29 | #include "system.h" | |
30 | #include "coretypes.h" | |
31 | #include "tm.h" | |
32 | #include "hard-reg-set.h" | |
33 | #include "rtl.h" | |
34 | #include "tm_p.h" | |
35 | #include "insn-config.h" | |
36 | #include "recog.h" | |
37 | #include "output.h" | |
38 | #include "regs.h" | |
39 | #include "function.h" | |
40 | #include "expr.h" | |
41 | #include "basic-block.h" | |
42 | #include "except.h" | |
43 | #include "df.h" | |
44 | #include "ira.h" | |
45 | #include "sparseset.h" | |
46 | #include "lra-int.h" | |
47 | ||
48 | /* Program points are enumerated by numbers from range | |
49 | 0..LRA_LIVE_MAX_POINT-1. There are approximately two times more | |
50 | program points than insns. Program points are places in the | |
51 | program where liveness info can be changed. In most general case | |
52 | (there are more complicated cases too) some program points | |
53 | correspond to places where input operand dies and other ones | |
54 | correspond to places where output operands are born. */ | |
55 | int lra_live_max_point; | |
56 | ||
57 | /* Accumulated execution frequency of all references for each hard | |
58 | register. */ | |
59 | int lra_hard_reg_usage[FIRST_PSEUDO_REGISTER]; | |
60 | ||
61 | /* A global flag whose true value says to build live ranges for all | |
62 | pseudos, otherwise the live ranges only for pseudos got memory is | |
63 | build. True value means also building copies and setting up hard | |
64 | register preferences. The complete info is necessary only for the | |
65 | assignment pass. The complete info is not needed for the | |
66 | coalescing and spill passes. */ | |
67 | static bool complete_info_p; | |
68 | ||
69 | /* Pseudos live at current point in the RTL scan. */ | |
70 | static sparseset pseudos_live; | |
71 | ||
72 | /* Pseudos probably living through calls and setjumps. As setjump is | |
73 | a call too, if a bit in PSEUDOS_LIVE_THROUGH_SETJUMPS is set up | |
74 | then the corresponding bit in PSEUDOS_LIVE_THROUGH_CALLS is set up | |
75 | too. These data are necessary for cases when only one subreg of a | |
76 | multi-reg pseudo is set up after a call. So we decide it is | |
77 | probably live when traversing bb backward. We are sure about | |
78 | living when we see its usage or definition of the pseudo. */ | |
79 | static sparseset pseudos_live_through_calls; | |
80 | static sparseset pseudos_live_through_setjumps; | |
81 | ||
82 | /* Set of hard regs (except eliminable ones) currently live. */ | |
83 | static HARD_REG_SET hard_regs_live; | |
84 | ||
85 | /* Set of pseudos and hard registers start living/dying in the current | |
86 | insn. These sets are used to update REG_DEAD and REG_UNUSED notes | |
87 | in the insn. */ | |
88 | static sparseset start_living, start_dying; | |
89 | ||
90 | /* Set of pseudos and hard regs dead and unused in the current | |
91 | insn. */ | |
92 | static sparseset unused_set, dead_set; | |
93 | ||
94 | /* Pool for pseudo live ranges. */ | |
95 | static alloc_pool live_range_pool; | |
96 | ||
97 | /* Free live range LR. */ | |
98 | static void | |
99 | free_live_range (lra_live_range_t lr) | |
100 | { | |
101 | pool_free (live_range_pool, lr); | |
102 | } | |
103 | ||
104 | /* Free live range list LR. */ | |
105 | static void | |
106 | free_live_range_list (lra_live_range_t lr) | |
107 | { | |
108 | lra_live_range_t next; | |
109 | ||
110 | while (lr != NULL) | |
111 | { | |
112 | next = lr->next; | |
113 | free_live_range (lr); | |
114 | lr = next; | |
115 | } | |
116 | } | |
117 | ||
118 | /* Create and return pseudo live range with given attributes. */ | |
119 | static lra_live_range_t | |
120 | create_live_range (int regno, int start, int finish, lra_live_range_t next) | |
121 | { | |
122 | lra_live_range_t p; | |
123 | ||
124 | p = (lra_live_range_t) pool_alloc (live_range_pool); | |
125 | p->regno = regno; | |
126 | p->start = start; | |
127 | p->finish = finish; | |
128 | p->next = next; | |
129 | return p; | |
130 | } | |
131 | ||
132 | /* Copy live range R and return the result. */ | |
133 | static lra_live_range_t | |
134 | copy_live_range (lra_live_range_t r) | |
135 | { | |
136 | lra_live_range_t p; | |
137 | ||
138 | p = (lra_live_range_t) pool_alloc (live_range_pool); | |
139 | *p = *r; | |
140 | return p; | |
141 | } | |
142 | ||
143 | /* Copy live range list given by its head R and return the result. */ | |
144 | lra_live_range_t | |
145 | lra_copy_live_range_list (lra_live_range_t r) | |
146 | { | |
147 | lra_live_range_t p, first, *chain; | |
148 | ||
149 | first = NULL; | |
150 | for (chain = &first; r != NULL; r = r->next) | |
151 | { | |
152 | p = copy_live_range (r); | |
153 | *chain = p; | |
154 | chain = &p->next; | |
155 | } | |
156 | return first; | |
157 | } | |
158 | ||
159 | /* Merge *non-intersected* ranges R1 and R2 and returns the result. | |
160 | The function maintains the order of ranges and tries to minimize | |
161 | size of the result range list. Ranges R1 and R2 may not be used | |
162 | after the call. */ | |
163 | lra_live_range_t | |
164 | lra_merge_live_ranges (lra_live_range_t r1, lra_live_range_t r2) | |
165 | { | |
166 | lra_live_range_t first, last, temp; | |
167 | ||
168 | if (r1 == NULL) | |
169 | return r2; | |
170 | if (r2 == NULL) | |
171 | return r1; | |
172 | for (first = last = NULL; r1 != NULL && r2 != NULL;) | |
173 | { | |
174 | if (r1->start < r2->start) | |
175 | { | |
176 | temp = r1; | |
177 | r1 = r2; | |
178 | r2 = temp; | |
179 | } | |
180 | if (r1->start == r2->finish + 1) | |
181 | { | |
182 | /* Joint ranges: merge r1 and r2 into r1. */ | |
183 | r1->start = r2->start; | |
184 | temp = r2; | |
185 | r2 = r2->next; | |
186 | pool_free (live_range_pool, temp); | |
187 | } | |
188 | else | |
189 | { | |
190 | gcc_assert (r2->finish + 1 < r1->start); | |
191 | /* Add r1 to the result. */ | |
192 | if (first == NULL) | |
193 | first = last = r1; | |
194 | else | |
195 | { | |
196 | last->next = r1; | |
197 | last = r1; | |
198 | } | |
199 | r1 = r1->next; | |
200 | } | |
201 | } | |
202 | if (r1 != NULL) | |
203 | { | |
204 | if (first == NULL) | |
205 | first = r1; | |
206 | else | |
207 | last->next = r1; | |
208 | } | |
209 | else | |
210 | { | |
211 | lra_assert (r2 != NULL); | |
212 | if (first == NULL) | |
213 | first = r2; | |
214 | else | |
215 | last->next = r2; | |
216 | } | |
217 | return first; | |
218 | } | |
219 | ||
220 | /* Return TRUE if live ranges R1 and R2 intersect. */ | |
221 | bool | |
222 | lra_intersected_live_ranges_p (lra_live_range_t r1, lra_live_range_t r2) | |
223 | { | |
224 | /* Remember the live ranges are always kept ordered. */ | |
225 | while (r1 != NULL && r2 != NULL) | |
226 | { | |
227 | if (r1->start > r2->finish) | |
228 | r1 = r1->next; | |
229 | else if (r2->start > r1->finish) | |
230 | r2 = r2->next; | |
231 | else | |
232 | return true; | |
233 | } | |
234 | return false; | |
235 | } | |
236 | ||
237 | /* The function processing birth of hard register REGNO. It updates | |
238 | living hard regs, conflict hard regs for living pseudos, and | |
239 | START_LIVING. */ | |
240 | static void | |
241 | make_hard_regno_born (int regno) | |
242 | { | |
243 | unsigned int i; | |
244 | ||
245 | lra_assert (regno < FIRST_PSEUDO_REGISTER); | |
246 | if (TEST_HARD_REG_BIT (lra_no_alloc_regs, regno) | |
247 | || TEST_HARD_REG_BIT (hard_regs_live, regno)) | |
248 | return; | |
249 | SET_HARD_REG_BIT (hard_regs_live, regno); | |
250 | sparseset_set_bit (start_living, regno); | |
251 | EXECUTE_IF_SET_IN_SPARSESET (pseudos_live, i) | |
252 | SET_HARD_REG_BIT (lra_reg_info[i].conflict_hard_regs, regno); | |
253 | } | |
254 | ||
255 | /* Process the death of hard register REGNO. This updates | |
256 | hard_regs_live and START_DYING. */ | |
257 | static void | |
258 | make_hard_regno_dead (int regno) | |
259 | { | |
260 | lra_assert (regno < FIRST_PSEUDO_REGISTER); | |
261 | if (TEST_HARD_REG_BIT (lra_no_alloc_regs, regno) | |
262 | || ! TEST_HARD_REG_BIT (hard_regs_live, regno)) | |
263 | return; | |
264 | sparseset_set_bit (start_dying, regno); | |
265 | CLEAR_HARD_REG_BIT (hard_regs_live, regno); | |
266 | } | |
267 | ||
268 | /* Mark pseudo REGNO as living at program point POINT, update conflicting | |
269 | hard registers of the pseudo and START_LIVING, and start a new live | |
270 | range for the pseudo corresponding to REGNO if it is necessary. */ | |
271 | static void | |
272 | mark_pseudo_live (int regno, int point) | |
273 | { | |
274 | lra_live_range_t p; | |
275 | ||
276 | lra_assert (regno >= FIRST_PSEUDO_REGISTER); | |
277 | lra_assert (! sparseset_bit_p (pseudos_live, regno)); | |
278 | sparseset_set_bit (pseudos_live, regno); | |
279 | IOR_HARD_REG_SET (lra_reg_info[regno].conflict_hard_regs, hard_regs_live); | |
280 | ||
281 | if ((complete_info_p || lra_get_regno_hard_regno (regno) < 0) | |
282 | && ((p = lra_reg_info[regno].live_ranges) == NULL | |
283 | || (p->finish != point && p->finish + 1 != point))) | |
284 | lra_reg_info[regno].live_ranges | |
285 | = create_live_range (regno, point, -1, p); | |
286 | sparseset_set_bit (start_living, regno); | |
287 | } | |
288 | ||
289 | /* Mark pseudo REGNO as not living at program point POINT and update | |
290 | START_DYING. | |
291 | This finishes the current live range for the pseudo corresponding | |
292 | to REGNO. */ | |
293 | static void | |
294 | mark_pseudo_dead (int regno, int point) | |
295 | { | |
296 | lra_live_range_t p; | |
297 | ||
298 | lra_assert (regno >= FIRST_PSEUDO_REGISTER); | |
299 | lra_assert (sparseset_bit_p (pseudos_live, regno)); | |
300 | sparseset_clear_bit (pseudos_live, regno); | |
301 | sparseset_set_bit (start_dying, regno); | |
302 | if (complete_info_p || lra_get_regno_hard_regno (regno) < 0) | |
303 | { | |
304 | p = lra_reg_info[regno].live_ranges; | |
305 | lra_assert (p != NULL); | |
306 | p->finish = point; | |
307 | } | |
308 | } | |
309 | ||
310 | /* Mark register REGNO (pseudo or hard register) in MODE as live | |
311 | at program point POINT. | |
312 | Return TRUE if the liveness tracking sets were modified, | |
313 | or FALSE if nothing changed. */ | |
314 | static bool | |
315 | mark_regno_live (int regno, enum machine_mode mode, int point) | |
316 | { | |
317 | int last; | |
318 | bool changed = false; | |
319 | ||
320 | if (regno < FIRST_PSEUDO_REGISTER) | |
321 | { | |
322 | for (last = regno + hard_regno_nregs[regno][mode]; | |
323 | regno < last; | |
324 | regno++) | |
325 | make_hard_regno_born (regno); | |
326 | } | |
327 | else if (! sparseset_bit_p (pseudos_live, regno)) | |
328 | { | |
329 | mark_pseudo_live (regno, point); | |
330 | changed = true; | |
331 | } | |
332 | return changed; | |
333 | } | |
334 | ||
335 | ||
336 | /* Mark register REGNO in MODE as dead at program point POINT. | |
337 | Return TRUE if the liveness tracking sets were modified, | |
338 | or FALSE if nothing changed. */ | |
339 | static bool | |
340 | mark_regno_dead (int regno, enum machine_mode mode, int point) | |
341 | { | |
342 | int last; | |
343 | bool changed = false; | |
344 | ||
345 | if (regno < FIRST_PSEUDO_REGISTER) | |
346 | { | |
347 | for (last = regno + hard_regno_nregs[regno][mode]; | |
348 | regno < last; | |
349 | regno++) | |
350 | make_hard_regno_dead (regno); | |
351 | } | |
352 | else if (sparseset_bit_p (pseudos_live, regno)) | |
353 | { | |
354 | mark_pseudo_dead (regno, point); | |
355 | changed = true; | |
356 | } | |
357 | return changed; | |
358 | } | |
359 | ||
360 | /* Insn currently scanned. */ | |
361 | static rtx curr_insn; | |
362 | /* The insn data. */ | |
363 | static lra_insn_recog_data_t curr_id; | |
364 | /* The insn static data. */ | |
365 | static struct lra_static_insn_data *curr_static_id; | |
366 | ||
367 | /* Return true when one of the predecessor edges of BB is marked with | |
368 | EDGE_ABNORMAL_CALL or EDGE_EH. */ | |
369 | static bool | |
370 | bb_has_abnormal_call_pred (basic_block bb) | |
371 | { | |
372 | edge e; | |
373 | edge_iterator ei; | |
374 | ||
375 | FOR_EACH_EDGE (e, ei, bb->preds) | |
376 | { | |
377 | if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH)) | |
378 | return true; | |
379 | } | |
380 | return false; | |
381 | } | |
382 | ||
383 | /* Vec containing execution frequencies of program points. */ | |
f1f41a6c | 384 | static vec<int> point_freq_vec; |
c6a6cdaa | 385 | |
386 | /* The start of the above vector elements. */ | |
387 | int *lra_point_freq; | |
388 | ||
389 | /* Increment the current program point POINT to the next point which has | |
390 | execution frequency FREQ. */ | |
391 | static void | |
392 | next_program_point (int &point, int freq) | |
393 | { | |
f1f41a6c | 394 | point_freq_vec.safe_push (freq); |
395 | lra_point_freq = point_freq_vec.address (); | |
c6a6cdaa | 396 | point++; |
397 | } | |
398 | ||
399 | /* Update the preference of HARD_REGNO for pseudo REGNO by PROFIT. */ | |
400 | void | |
401 | lra_setup_reload_pseudo_preferenced_hard_reg (int regno, | |
402 | int hard_regno, int profit) | |
403 | { | |
404 | lra_assert (regno >= lra_constraint_new_regno_start); | |
405 | if (lra_reg_info[regno].preferred_hard_regno1 == hard_regno) | |
406 | lra_reg_info[regno].preferred_hard_regno_profit1 += profit; | |
407 | else if (lra_reg_info[regno].preferred_hard_regno2 == hard_regno) | |
408 | lra_reg_info[regno].preferred_hard_regno_profit2 += profit; | |
409 | else if (lra_reg_info[regno].preferred_hard_regno1 < 0) | |
410 | { | |
411 | lra_reg_info[regno].preferred_hard_regno1 = hard_regno; | |
412 | lra_reg_info[regno].preferred_hard_regno_profit1 = profit; | |
413 | } | |
414 | else if (lra_reg_info[regno].preferred_hard_regno2 < 0 | |
415 | || profit > lra_reg_info[regno].preferred_hard_regno_profit2) | |
416 | { | |
417 | lra_reg_info[regno].preferred_hard_regno2 = hard_regno; | |
418 | lra_reg_info[regno].preferred_hard_regno_profit2 = profit; | |
419 | } | |
420 | else | |
421 | return; | |
422 | /* Keep the 1st hard regno as more profitable. */ | |
423 | if (lra_reg_info[regno].preferred_hard_regno1 >= 0 | |
424 | && lra_reg_info[regno].preferred_hard_regno2 >= 0 | |
425 | && (lra_reg_info[regno].preferred_hard_regno_profit2 | |
426 | > lra_reg_info[regno].preferred_hard_regno_profit1)) | |
427 | { | |
428 | int temp; | |
429 | ||
430 | temp = lra_reg_info[regno].preferred_hard_regno1; | |
431 | lra_reg_info[regno].preferred_hard_regno1 | |
432 | = lra_reg_info[regno].preferred_hard_regno2; | |
433 | lra_reg_info[regno].preferred_hard_regno2 = temp; | |
434 | temp = lra_reg_info[regno].preferred_hard_regno_profit1; | |
435 | lra_reg_info[regno].preferred_hard_regno_profit1 | |
436 | = lra_reg_info[regno].preferred_hard_regno_profit2; | |
437 | lra_reg_info[regno].preferred_hard_regno_profit2 = temp; | |
438 | } | |
439 | if (lra_dump_file != NULL) | |
440 | { | |
441 | if ((hard_regno = lra_reg_info[regno].preferred_hard_regno1) >= 0) | |
442 | fprintf (lra_dump_file, | |
443 | " Hard reg %d is preferable by r%d with profit %d\n", | |
444 | hard_regno, regno, | |
445 | lra_reg_info[regno].preferred_hard_regno_profit1); | |
446 | if ((hard_regno = lra_reg_info[regno].preferred_hard_regno2) >= 0) | |
447 | fprintf (lra_dump_file, | |
448 | " Hard reg %d is preferable by r%d with profit %d\n", | |
449 | hard_regno, regno, | |
450 | lra_reg_info[regno].preferred_hard_regno_profit2); | |
451 | } | |
452 | } | |
453 | ||
454 | /* Check that REGNO living through calls and setjumps, set up conflict | |
455 | regs, and clear corresponding bits in PSEUDOS_LIVE_THROUGH_CALLS and | |
456 | PSEUDOS_LIVE_THROUGH_SETJUMPS. */ | |
457 | static inline void | |
458 | check_pseudos_live_through_calls (int regno) | |
459 | { | |
a766a8b0 | 460 | int hr; |
461 | ||
c6a6cdaa | 462 | if (! sparseset_bit_p (pseudos_live_through_calls, regno)) |
463 | return; | |
464 | sparseset_clear_bit (pseudos_live_through_calls, regno); | |
465 | IOR_HARD_REG_SET (lra_reg_info[regno].conflict_hard_regs, | |
466 | call_used_reg_set); | |
a766a8b0 | 467 | |
468 | for (hr = 0; hr < FIRST_PSEUDO_REGISTER; hr++) | |
469 | if (HARD_REGNO_CALL_PART_CLOBBERED (hr, PSEUDO_REGNO_MODE (regno))) | |
470 | SET_HARD_REG_BIT (lra_reg_info[regno].conflict_hard_regs, hr); | |
c6a6cdaa | 471 | #ifdef ENABLE_CHECKING |
472 | lra_reg_info[regno].call_p = true; | |
473 | #endif | |
474 | if (! sparseset_bit_p (pseudos_live_through_setjumps, regno)) | |
475 | return; | |
476 | sparseset_clear_bit (pseudos_live_through_setjumps, regno); | |
477 | /* Don't allocate pseudos that cross setjmps or any call, if this | |
478 | function receives a nonlocal goto. */ | |
479 | SET_HARD_REG_SET (lra_reg_info[regno].conflict_hard_regs); | |
480 | } | |
481 | ||
482 | /* Process insns of the basic block BB to update pseudo live ranges, | |
483 | pseudo hard register conflicts, and insn notes. We do it on | |
484 | backward scan of BB insns. CURR_POINT is the program point where | |
485 | BB ends. The function updates this counter and returns in | |
486 | CURR_POINT the program point where BB starts. */ | |
487 | static void | |
488 | process_bb_lives (basic_block bb, int &curr_point) | |
489 | { | |
490 | int i, regno, freq; | |
491 | unsigned int j; | |
492 | bitmap_iterator bi; | |
493 | bitmap reg_live_out; | |
494 | unsigned int px; | |
495 | rtx link, *link_loc; | |
496 | bool need_curr_point_incr; | |
497 | ||
498 | reg_live_out = df_get_live_out (bb); | |
499 | sparseset_clear (pseudos_live); | |
500 | sparseset_clear (pseudos_live_through_calls); | |
501 | sparseset_clear (pseudos_live_through_setjumps); | |
502 | REG_SET_TO_HARD_REG_SET (hard_regs_live, reg_live_out); | |
503 | AND_COMPL_HARD_REG_SET (hard_regs_live, eliminable_regset); | |
504 | AND_COMPL_HARD_REG_SET (hard_regs_live, lra_no_alloc_regs); | |
505 | EXECUTE_IF_SET_IN_BITMAP (reg_live_out, FIRST_PSEUDO_REGISTER, j, bi) | |
506 | mark_pseudo_live (j, curr_point); | |
507 | ||
508 | freq = REG_FREQ_FROM_BB (bb); | |
509 | ||
510 | if (lra_dump_file != NULL) | |
511 | fprintf (lra_dump_file, " BB %d\n", bb->index); | |
512 | ||
513 | /* Scan the code of this basic block, noting which pseudos and hard | |
514 | regs are born or die. | |
515 | ||
516 | Note that this loop treats uninitialized values as live until the | |
517 | beginning of the block. For example, if an instruction uses | |
518 | (reg:DI foo), and only (subreg:SI (reg:DI foo) 0) is ever set, | |
519 | FOO will remain live until the beginning of the block. Likewise | |
520 | if FOO is not set at all. This is unnecessarily pessimistic, but | |
521 | it probably doesn't matter much in practice. */ | |
522 | FOR_BB_INSNS_REVERSE (bb, curr_insn) | |
523 | { | |
524 | bool call_p; | |
525 | int dst_regno, src_regno; | |
526 | rtx set; | |
527 | struct lra_insn_reg *reg; | |
528 | ||
529 | if (!NONDEBUG_INSN_P (curr_insn)) | |
530 | continue; | |
531 | ||
532 | curr_id = lra_get_insn_recog_data (curr_insn); | |
533 | curr_static_id = curr_id->insn_static_data; | |
534 | if (lra_dump_file != NULL) | |
535 | fprintf (lra_dump_file, " Insn %u: point = %d\n", | |
536 | INSN_UID (curr_insn), curr_point); | |
537 | ||
538 | /* Update max ref width and hard reg usage. */ | |
539 | for (reg = curr_id->regs; reg != NULL; reg = reg->next) | |
540 | if (reg->regno >= FIRST_PSEUDO_REGISTER | |
541 | && (GET_MODE_SIZE (reg->biggest_mode) | |
542 | > GET_MODE_SIZE (lra_reg_info[reg->regno].biggest_mode))) | |
543 | lra_reg_info[reg->regno].biggest_mode = reg->biggest_mode; | |
544 | else if (reg->regno < FIRST_PSEUDO_REGISTER) | |
545 | lra_hard_reg_usage[reg->regno] += freq; | |
546 | ||
547 | call_p = CALL_P (curr_insn); | |
548 | if (complete_info_p | |
549 | && (set = single_set (curr_insn)) != NULL_RTX | |
550 | && REG_P (SET_DEST (set)) && REG_P (SET_SRC (set)) | |
551 | /* Check that source regno does not conflict with | |
552 | destination regno to exclude most impossible | |
553 | preferences. */ | |
554 | && ((((src_regno = REGNO (SET_SRC (set))) >= FIRST_PSEUDO_REGISTER | |
555 | && ! sparseset_bit_p (pseudos_live, src_regno)) | |
556 | || (src_regno < FIRST_PSEUDO_REGISTER | |
557 | && ! TEST_HARD_REG_BIT (hard_regs_live, src_regno))) | |
558 | /* It might be 'inheritance pseudo <- reload pseudo'. */ | |
559 | || (src_regno >= lra_constraint_new_regno_start | |
560 | && ((int) REGNO (SET_DEST (set)) | |
561 | >= lra_constraint_new_regno_start)))) | |
562 | { | |
563 | int hard_regno = -1, regno = -1; | |
564 | ||
565 | dst_regno = REGNO (SET_DEST (set)); | |
566 | if (dst_regno >= lra_constraint_new_regno_start | |
567 | && src_regno >= lra_constraint_new_regno_start) | |
568 | lra_create_copy (dst_regno, src_regno, freq); | |
569 | else if (dst_regno >= lra_constraint_new_regno_start) | |
570 | { | |
571 | if ((hard_regno = src_regno) >= FIRST_PSEUDO_REGISTER) | |
572 | hard_regno = reg_renumber[src_regno]; | |
573 | regno = dst_regno; | |
574 | } | |
575 | else if (src_regno >= lra_constraint_new_regno_start) | |
576 | { | |
577 | if ((hard_regno = dst_regno) >= FIRST_PSEUDO_REGISTER) | |
578 | hard_regno = reg_renumber[dst_regno]; | |
579 | regno = src_regno; | |
580 | } | |
581 | if (regno >= 0 && hard_regno >= 0) | |
582 | lra_setup_reload_pseudo_preferenced_hard_reg | |
583 | (regno, hard_regno, freq); | |
584 | } | |
585 | ||
586 | sparseset_clear (start_living); | |
587 | ||
588 | /* Try to avoid unnecessary program point increments, this saves | |
589 | a lot of time in remove_some_program_points_and_update_live_ranges. | |
590 | We only need an increment if something becomes live or dies at this | |
591 | program point. */ | |
592 | need_curr_point_incr = false; | |
593 | ||
594 | /* Mark each defined value as live. We need to do this for | |
595 | unused values because they still conflict with quantities | |
596 | that are live at the time of the definition. */ | |
597 | for (reg = curr_id->regs; reg != NULL; reg = reg->next) | |
598 | if (reg->type != OP_IN) | |
599 | { | |
600 | need_curr_point_incr |= mark_regno_live (reg->regno, | |
601 | reg->biggest_mode, | |
602 | curr_point); | |
603 | check_pseudos_live_through_calls (reg->regno); | |
604 | } | |
605 | ||
606 | for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next) | |
607 | if (reg->type != OP_IN) | |
608 | make_hard_regno_born (reg->regno); | |
609 | ||
610 | sparseset_copy (unused_set, start_living); | |
611 | ||
612 | sparseset_clear (start_dying); | |
613 | ||
614 | /* See which defined values die here. */ | |
615 | for (reg = curr_id->regs; reg != NULL; reg = reg->next) | |
616 | if (reg->type == OP_OUT && ! reg->early_clobber && ! reg->subreg_p) | |
617 | need_curr_point_incr |= mark_regno_dead (reg->regno, | |
618 | reg->biggest_mode, | |
619 | curr_point); | |
620 | ||
621 | for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next) | |
622 | if (reg->type == OP_OUT && ! reg->early_clobber && ! reg->subreg_p) | |
623 | make_hard_regno_dead (reg->regno); | |
624 | ||
625 | if (call_p) | |
626 | { | |
627 | sparseset_ior (pseudos_live_through_calls, | |
628 | pseudos_live_through_calls, pseudos_live); | |
629 | if (cfun->has_nonlocal_label | |
630 | || find_reg_note (curr_insn, REG_SETJMP, | |
631 | NULL_RTX) != NULL_RTX) | |
632 | sparseset_ior (pseudos_live_through_setjumps, | |
633 | pseudos_live_through_setjumps, pseudos_live); | |
634 | } | |
635 | ||
636 | /* Increment the current program point if we must. */ | |
637 | if (need_curr_point_incr) | |
638 | next_program_point (curr_point, freq); | |
639 | ||
640 | sparseset_clear (start_living); | |
641 | ||
642 | need_curr_point_incr = false; | |
643 | ||
644 | /* Mark each used value as live. */ | |
645 | for (reg = curr_id->regs; reg != NULL; reg = reg->next) | |
646 | if (reg->type == OP_IN) | |
647 | { | |
648 | need_curr_point_incr |= mark_regno_live (reg->regno, | |
649 | reg->biggest_mode, | |
650 | curr_point); | |
651 | check_pseudos_live_through_calls (reg->regno); | |
652 | } | |
653 | ||
654 | for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next) | |
655 | if (reg->type == OP_IN) | |
656 | make_hard_regno_born (reg->regno); | |
657 | ||
658 | if (curr_id->arg_hard_regs != NULL) | |
659 | /* Make argument hard registers live. */ | |
660 | for (i = 0; (regno = curr_id->arg_hard_regs[i]) >= 0; i++) | |
661 | make_hard_regno_born (regno); | |
662 | ||
663 | sparseset_and_compl (dead_set, start_living, start_dying); | |
664 | ||
665 | /* Mark early clobber outputs dead. */ | |
666 | for (reg = curr_id->regs; reg != NULL; reg = reg->next) | |
667 | if (reg->type == OP_OUT && reg->early_clobber && ! reg->subreg_p) | |
668 | need_curr_point_incr = mark_regno_dead (reg->regno, | |
669 | reg->biggest_mode, | |
670 | curr_point); | |
671 | ||
672 | for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next) | |
673 | if (reg->type == OP_OUT && reg->early_clobber && ! reg->subreg_p) | |
674 | make_hard_regno_dead (reg->regno); | |
675 | ||
676 | if (need_curr_point_incr) | |
677 | next_program_point (curr_point, freq); | |
678 | ||
679 | /* Update notes. */ | |
680 | for (link_loc = ®_NOTES (curr_insn); (link = *link_loc) != NULL_RTX;) | |
681 | { | |
682 | if (REG_NOTE_KIND (link) != REG_DEAD | |
683 | && REG_NOTE_KIND (link) != REG_UNUSED) | |
684 | ; | |
685 | else if (REG_P (XEXP (link, 0))) | |
686 | { | |
687 | regno = REGNO (XEXP (link, 0)); | |
688 | if ((REG_NOTE_KIND (link) == REG_DEAD | |
689 | && ! sparseset_bit_p (dead_set, regno)) | |
690 | || (REG_NOTE_KIND (link) == REG_UNUSED | |
691 | && ! sparseset_bit_p (unused_set, regno))) | |
692 | { | |
693 | *link_loc = XEXP (link, 1); | |
694 | continue; | |
695 | } | |
696 | if (REG_NOTE_KIND (link) == REG_DEAD) | |
697 | sparseset_clear_bit (dead_set, regno); | |
698 | else if (REG_NOTE_KIND (link) == REG_UNUSED) | |
699 | sparseset_clear_bit (unused_set, regno); | |
700 | } | |
701 | link_loc = &XEXP (link, 1); | |
702 | } | |
703 | EXECUTE_IF_SET_IN_SPARSESET (dead_set, j) | |
704 | add_reg_note (curr_insn, REG_DEAD, regno_reg_rtx[j]); | |
705 | EXECUTE_IF_SET_IN_SPARSESET (unused_set, j) | |
706 | add_reg_note (curr_insn, REG_UNUSED, regno_reg_rtx[j]); | |
707 | } | |
708 | ||
709 | #ifdef EH_RETURN_DATA_REGNO | |
710 | if (bb_has_eh_pred (bb)) | |
711 | for (j = 0; ; ++j) | |
712 | { | |
713 | unsigned int regno = EH_RETURN_DATA_REGNO (j); | |
714 | ||
715 | if (regno == INVALID_REGNUM) | |
716 | break; | |
717 | make_hard_regno_born (regno); | |
718 | } | |
719 | #endif | |
720 | ||
721 | /* Pseudos can't go in stack regs at the start of a basic block that | |
722 | is reached by an abnormal edge. Likewise for call clobbered regs, | |
723 | because caller-save, fixup_abnormal_edges and possibly the table | |
724 | driven EH machinery are not quite ready to handle such pseudos | |
725 | live across such edges. */ | |
726 | if (bb_has_abnormal_pred (bb)) | |
727 | { | |
728 | #ifdef STACK_REGS | |
729 | EXECUTE_IF_SET_IN_SPARSESET (pseudos_live, px) | |
730 | lra_reg_info[px].no_stack_p = true; | |
731 | for (px = FIRST_STACK_REG; px <= LAST_STACK_REG; px++) | |
732 | make_hard_regno_born (px); | |
733 | #endif | |
734 | /* No need to record conflicts for call clobbered regs if we | |
735 | have nonlocal labels around, as we don't ever try to | |
736 | allocate such regs in this case. */ | |
737 | if (!cfun->has_nonlocal_label && bb_has_abnormal_call_pred (bb)) | |
738 | for (px = 0; px < FIRST_PSEUDO_REGISTER; px++) | |
739 | if (call_used_regs[px]) | |
740 | make_hard_regno_born (px); | |
741 | } | |
742 | ||
743 | /* See if we'll need an increment at the end of this basic block. | |
744 | An increment is needed if the PSEUDOS_LIVE set is not empty, | |
745 | to make sure the finish points are set up correctly. */ | |
746 | need_curr_point_incr = (sparseset_cardinality (pseudos_live) > 0); | |
747 | ||
748 | EXECUTE_IF_SET_IN_SPARSESET (pseudos_live, i) | |
749 | mark_pseudo_dead (i, curr_point); | |
750 | ||
751 | EXECUTE_IF_SET_IN_BITMAP (df_get_live_in (bb), FIRST_PSEUDO_REGISTER, j, bi) | |
752 | { | |
753 | if (sparseset_cardinality (pseudos_live_through_calls) == 0) | |
754 | break; | |
755 | if (sparseset_bit_p (pseudos_live_through_calls, j)) | |
756 | check_pseudos_live_through_calls (j); | |
757 | } | |
758 | ||
759 | if (need_curr_point_incr) | |
760 | next_program_point (curr_point, freq); | |
761 | } | |
762 | ||
763 | /* Compress pseudo live ranges by removing program points where | |
764 | nothing happens. Complexity of many algorithms in LRA is linear | |
765 | function of program points number. To speed up the code we try to | |
766 | minimize the number of the program points here. */ | |
767 | static void | |
768 | remove_some_program_points_and_update_live_ranges (void) | |
769 | { | |
770 | unsigned i; | |
771 | int n, max_regno; | |
772 | int *map; | |
773 | lra_live_range_t r, prev_r, next_r; | |
774 | sbitmap born_or_dead, born, dead; | |
775 | sbitmap_iterator sbi; | |
776 | bool born_p, dead_p, prev_born_p, prev_dead_p; | |
777 | ||
778 | born = sbitmap_alloc (lra_live_max_point); | |
779 | dead = sbitmap_alloc (lra_live_max_point); | |
53c5d9d4 | 780 | bitmap_clear (born); |
781 | bitmap_clear (dead); | |
c6a6cdaa | 782 | max_regno = max_reg_num (); |
783 | for (i = FIRST_PSEUDO_REGISTER; i < (unsigned) max_regno; i++) | |
784 | { | |
785 | for (r = lra_reg_info[i].live_ranges; r != NULL; r = r->next) | |
786 | { | |
787 | lra_assert (r->start <= r->finish); | |
08b7917c | 788 | bitmap_set_bit (born, r->start); |
789 | bitmap_set_bit (dead, r->finish); | |
c6a6cdaa | 790 | } |
791 | } | |
792 | born_or_dead = sbitmap_alloc (lra_live_max_point); | |
53c5d9d4 | 793 | bitmap_ior (born_or_dead, born, dead); |
c6a6cdaa | 794 | map = XCNEWVEC (int, lra_live_max_point); |
795 | n = -1; | |
796 | prev_born_p = prev_dead_p = false; | |
0d211963 | 797 | EXECUTE_IF_SET_IN_BITMAP (born_or_dead, 0, i, sbi) |
c6a6cdaa | 798 | { |
08b7917c | 799 | born_p = bitmap_bit_p (born, i); |
800 | dead_p = bitmap_bit_p (dead, i); | |
c6a6cdaa | 801 | if ((prev_born_p && ! prev_dead_p && born_p && ! dead_p) |
802 | || (prev_dead_p && ! prev_born_p && dead_p && ! born_p)) | |
803 | { | |
804 | map[i] = n; | |
805 | lra_point_freq[n] = MAX (lra_point_freq[n], lra_point_freq[i]); | |
806 | } | |
807 | else | |
808 | { | |
809 | map[i] = ++n; | |
810 | lra_point_freq[n] = lra_point_freq[i]; | |
811 | } | |
812 | prev_born_p = born_p; | |
813 | prev_dead_p = dead_p; | |
814 | } | |
815 | sbitmap_free (born_or_dead); | |
816 | sbitmap_free (born); | |
817 | sbitmap_free (dead); | |
818 | n++; | |
819 | if (lra_dump_file != NULL) | |
820 | fprintf (lra_dump_file, "Compressing live ranges: from %d to %d - %d%%\n", | |
821 | lra_live_max_point, n, 100 * n / lra_live_max_point); | |
822 | if (n < lra_live_max_point) | |
823 | { | |
824 | lra_live_max_point = n; | |
825 | for (i = FIRST_PSEUDO_REGISTER; i < (unsigned) max_regno; i++) | |
826 | { | |
827 | for (prev_r = NULL, r = lra_reg_info[i].live_ranges; | |
828 | r != NULL; | |
829 | r = next_r) | |
830 | { | |
831 | next_r = r->next; | |
832 | r->start = map[r->start]; | |
833 | r->finish = map[r->finish]; | |
834 | if (prev_r == NULL || prev_r->start > r->finish + 1) | |
835 | { | |
836 | prev_r = r; | |
837 | continue; | |
838 | } | |
839 | prev_r->start = r->start; | |
840 | prev_r->next = next_r; | |
841 | free_live_range (r); | |
842 | } | |
843 | } | |
844 | } | |
845 | free (map); | |
846 | } | |
847 | ||
848 | /* Print live ranges R to file F. */ | |
849 | void | |
850 | lra_print_live_range_list (FILE *f, lra_live_range_t r) | |
851 | { | |
852 | for (; r != NULL; r = r->next) | |
853 | fprintf (f, " [%d..%d]", r->start, r->finish); | |
854 | fprintf (f, "\n"); | |
855 | } | |
856 | ||
c7d89805 | 857 | DEBUG_FUNCTION void |
858 | debug (lra_live_range &ref) | |
859 | { | |
860 | lra_print_live_range_list (stderr, &ref); | |
861 | } | |
862 | ||
863 | DEBUG_FUNCTION void | |
864 | debug (lra_live_range *ptr) | |
865 | { | |
866 | if (ptr) | |
867 | debug (*ptr); | |
868 | else | |
869 | fprintf (stderr, "<nil>\n"); | |
870 | } | |
871 | ||
c6a6cdaa | 872 | /* Print live ranges R to stderr. */ |
873 | void | |
874 | lra_debug_live_range_list (lra_live_range_t r) | |
875 | { | |
876 | lra_print_live_range_list (stderr, r); | |
877 | } | |
878 | ||
879 | /* Print live ranges of pseudo REGNO to file F. */ | |
880 | static void | |
881 | print_pseudo_live_ranges (FILE *f, int regno) | |
882 | { | |
883 | if (lra_reg_info[regno].live_ranges == NULL) | |
884 | return; | |
885 | fprintf (f, " r%d:", regno); | |
886 | lra_print_live_range_list (f, lra_reg_info[regno].live_ranges); | |
887 | } | |
888 | ||
889 | /* Print live ranges of pseudo REGNO to stderr. */ | |
890 | void | |
891 | lra_debug_pseudo_live_ranges (int regno) | |
892 | { | |
893 | print_pseudo_live_ranges (stderr, regno); | |
894 | } | |
895 | ||
896 | /* Print live ranges of all pseudos to file F. */ | |
897 | static void | |
898 | print_live_ranges (FILE *f) | |
899 | { | |
900 | int i, max_regno; | |
901 | ||
902 | max_regno = max_reg_num (); | |
903 | for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++) | |
904 | print_pseudo_live_ranges (f, i); | |
905 | } | |
906 | ||
907 | /* Print live ranges of all pseudos to stderr. */ | |
908 | void | |
909 | lra_debug_live_ranges (void) | |
910 | { | |
911 | print_live_ranges (stderr); | |
912 | } | |
913 | ||
914 | /* Compress pseudo live ranges. */ | |
915 | static void | |
916 | compress_live_ranges (void) | |
917 | { | |
918 | remove_some_program_points_and_update_live_ranges (); | |
919 | if (lra_dump_file != NULL) | |
920 | { | |
921 | fprintf (lra_dump_file, "Ranges after the compression:\n"); | |
922 | print_live_ranges (lra_dump_file); | |
923 | } | |
924 | } | |
925 | ||
926 | /* The number of the current live range pass. */ | |
927 | int lra_live_range_iter; | |
928 | ||
929 | /* The main entry function creates live ranges only for memory pseudos | |
930 | (or for all ones if ALL_P), set up CONFLICT_HARD_REGS for | |
931 | the pseudos. */ | |
932 | void | |
933 | lra_create_live_ranges (bool all_p) | |
934 | { | |
935 | basic_block bb; | |
936 | int i, hard_regno, max_regno = max_reg_num (); | |
937 | int curr_point; | |
dbb9a07c | 938 | bool have_referenced_pseudos = false; |
c6a6cdaa | 939 | |
940 | timevar_push (TV_LRA_CREATE_LIVE_RANGES); | |
941 | ||
942 | complete_info_p = all_p; | |
943 | if (lra_dump_file != NULL) | |
944 | fprintf (lra_dump_file, | |
945 | "\n********** Pseudo live ranges #%d: **********\n\n", | |
946 | ++lra_live_range_iter); | |
947 | memset (lra_hard_reg_usage, 0, sizeof (lra_hard_reg_usage)); | |
948 | for (i = 0; i < max_regno; i++) | |
949 | { | |
950 | lra_reg_info[i].live_ranges = NULL; | |
951 | CLEAR_HARD_REG_SET (lra_reg_info[i].conflict_hard_regs); | |
952 | lra_reg_info[i].preferred_hard_regno1 = -1; | |
953 | lra_reg_info[i].preferred_hard_regno2 = -1; | |
954 | lra_reg_info[i].preferred_hard_regno_profit1 = 0; | |
955 | lra_reg_info[i].preferred_hard_regno_profit2 = 0; | |
956 | #ifdef STACK_REGS | |
957 | lra_reg_info[i].no_stack_p = false; | |
958 | #endif | |
fc8a0f60 | 959 | /* The biggest mode is already set but its value might be to |
960 | conservative because of recent transformation. Here in this | |
961 | file we recalculate it again as it costs practically | |
962 | nothing. */ | |
c6a6cdaa | 963 | if (regno_reg_rtx[i] != NULL_RTX) |
964 | lra_reg_info[i].biggest_mode = GET_MODE (regno_reg_rtx[i]); | |
965 | else | |
966 | lra_reg_info[i].biggest_mode = VOIDmode; | |
967 | #ifdef ENABLE_CHECKING | |
968 | lra_reg_info[i].call_p = false; | |
969 | #endif | |
970 | if (i >= FIRST_PSEUDO_REGISTER | |
dbb9a07c | 971 | && lra_reg_info[i].nrefs != 0) |
972 | { | |
973 | if ((hard_regno = reg_renumber[i]) >= 0) | |
974 | lra_hard_reg_usage[hard_regno] += lra_reg_info[i].freq; | |
975 | have_referenced_pseudos = true; | |
976 | } | |
c6a6cdaa | 977 | } |
978 | lra_free_copies (); | |
dbb9a07c | 979 | |
980 | /* Under some circumstances, we can have functions without pseudo | |
981 | registers. For such functions, lra_live_max_point will be 0, | |
982 | see e.g. PR55604, and there's nothing more to do for us here. */ | |
983 | if (! have_referenced_pseudos) | |
984 | { | |
985 | timevar_pop (TV_LRA_CREATE_LIVE_RANGES); | |
986 | return; | |
987 | } | |
988 | ||
c6a6cdaa | 989 | pseudos_live = sparseset_alloc (max_regno); |
990 | pseudos_live_through_calls = sparseset_alloc (max_regno); | |
991 | pseudos_live_through_setjumps = sparseset_alloc (max_regno); | |
992 | start_living = sparseset_alloc (max_regno); | |
993 | start_dying = sparseset_alloc (max_regno); | |
994 | dead_set = sparseset_alloc (max_regno); | |
995 | unused_set = sparseset_alloc (max_regno); | |
996 | curr_point = 0; | |
f1f41a6c | 997 | point_freq_vec.create (get_max_uid () * 2); |
998 | lra_point_freq = point_freq_vec.address (); | |
fe672ac0 | 999 | int *post_order_rev_cfg = XNEWVEC (int, last_basic_block_for_fn (cfun)); |
c6a6cdaa | 1000 | int n_blocks_inverted = inverted_post_order_compute (post_order_rev_cfg); |
a28770e1 | 1001 | lra_assert (n_blocks_inverted == n_basic_blocks_for_fn (cfun)); |
c6a6cdaa | 1002 | for (i = n_blocks_inverted - 1; i >= 0; --i) |
1003 | { | |
f5a6b05f | 1004 | bb = BASIC_BLOCK_FOR_FN (cfun, post_order_rev_cfg[i]); |
34154e27 | 1005 | if (bb == EXIT_BLOCK_PTR_FOR_FN (cfun) || bb |
1006 | == ENTRY_BLOCK_PTR_FOR_FN (cfun)) | |
c6a6cdaa | 1007 | continue; |
1008 | process_bb_lives (bb, curr_point); | |
1009 | } | |
1010 | free (post_order_rev_cfg); | |
1011 | lra_live_max_point = curr_point; | |
dbb9a07c | 1012 | gcc_checking_assert (lra_live_max_point > 0); |
c6a6cdaa | 1013 | if (lra_dump_file != NULL) |
1014 | print_live_ranges (lra_dump_file); | |
1015 | /* Clean up. */ | |
1016 | sparseset_free (unused_set); | |
1017 | sparseset_free (dead_set); | |
1018 | sparseset_free (start_dying); | |
1019 | sparseset_free (start_living); | |
1020 | sparseset_free (pseudos_live_through_calls); | |
1021 | sparseset_free (pseudos_live_through_setjumps); | |
1022 | sparseset_free (pseudos_live); | |
1023 | compress_live_ranges (); | |
1024 | timevar_pop (TV_LRA_CREATE_LIVE_RANGES); | |
1025 | } | |
1026 | ||
1027 | /* Finish all live ranges. */ | |
1028 | void | |
1029 | lra_clear_live_ranges (void) | |
1030 | { | |
1031 | int i; | |
1032 | ||
1033 | for (i = 0; i < max_reg_num (); i++) | |
1034 | free_live_range_list (lra_reg_info[i].live_ranges); | |
f1f41a6c | 1035 | point_freq_vec.release (); |
c6a6cdaa | 1036 | } |
1037 | ||
1038 | /* Initialize live ranges data once per function. */ | |
1039 | void | |
1040 | lra_live_ranges_init (void) | |
1041 | { | |
1042 | live_range_pool = create_alloc_pool ("live ranges", | |
1043 | sizeof (struct lra_live_range), 100); | |
1044 | } | |
1045 | ||
1046 | /* Finish live ranges data once per function. */ | |
1047 | void | |
1048 | lra_live_ranges_finish (void) | |
1049 | { | |
1050 | free_alloc_pool (live_range_pool); | |
1051 | } |