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[gcc.git] / gcc / lra.c
1 /* LRA (local register allocator) driver and LRA utilities.
2 Copyright (C) 2010, 2011, 2012
3 Free Software Foundation, Inc.
4 Contributed by Vladimir Makarov <vmakarov@redhat.com>.
5
6 This file is part of GCC.
7
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
12
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
21
22
23 /* The Local Register Allocator (LRA) is a replacement of former
24 reload pass. It is focused to simplify code solving the reload
25 pass tasks, to make the code maintenance easier, and to implement new
26 perspective optimizations.
27
28 The major LRA design solutions are:
29 o division small manageable, separated sub-tasks
30 o reflection of all transformations and decisions in RTL as more
31 as possible
32 o insn constraints as a primary source of the info (minimizing
33 number of target-depended macros/hooks)
34
35 In brief LRA works by iterative insn process with the final goal is
36 to satisfy all insn and address constraints:
37 o New reload insns (in brief reloads) and reload pseudos might be
38 generated;
39 o Some pseudos might be spilled to assign hard registers to
40 new reload pseudos;
41 o Changing spilled pseudos to stack memory or their equivalences;
42 o Allocation stack memory changes the address displacement and
43 new iteration is needed.
44
45 Here is block diagram of LRA passes:
46
47 ---------------------
48 | Undo inheritance | --------------- ---------------
49 | for spilled pseudos)| | Memory-memory | | New (and old) |
50 | and splits (for |<----| move coalesce |<-----| pseudos |
51 | pseudos got the | --------------- | assignment |
52 Start | same hard regs) | ---------------
53 | --------------------- ^
54 V | ---------------- |
55 ----------- V | Update virtual | |
56 | Remove |----> ------------>| register | |
57 | scratches | ^ | displacements | |
58 ----------- | ---------------- |
59 | | |
60 | V New |
61 ---------------- No ------------ pseudos -------------------
62 | Spilled pseudo | change |Constraints:| or insns | Inheritance/split |
63 | to memory |<-------| RTL |--------->| transformations |
64 | substitution | | transfor- | | in EBB scope |
65 ---------------- | mations | -------------------
66 | ------------
67 V
68 -------------------------
69 | Hard regs substitution, |
70 | devirtalization, and |------> Finish
71 | restoring scratches got |
72 | memory |
73 -------------------------
74
75 To speed up the process:
76 o We process only insns affected by changes on previous
77 iterations;
78 o We don't use DFA-infrastructure because it results in much slower
79 compiler speed than a special IR described below does;
80 o We use a special insn representation for quick access to insn
81 info which is always *synchronized* with the current RTL;
82 o Insn IR is minimized by memory. It is divided on three parts:
83 o one specific for each insn in RTL (only operand locations);
84 o one common for all insns in RTL with the same insn code
85 (different operand attributes from machine descriptions);
86 o one oriented for maintenance of live info (list of pseudos).
87 o Pseudo data:
88 o all insns where the pseudo is referenced;
89 o live info (conflicting hard regs, live ranges, # of
90 references etc);
91 o data used for assigning (preferred hard regs, costs etc).
92
93 This file contains LRA driver, LRA utility functions and data, and
94 code for dealing with scratches. */
95
96 #include "config.h"
97 #include "system.h"
98 #include "coretypes.h"
99 #include "tm.h"
100 #include "rtl.h"
101 #include "tm_p.h"
102 #include "regs.h"
103 #include "insn-config.h"
104 #include "insn-codes.h"
105 #include "recog.h"
106 #include "output.h"
107 #include "addresses.h"
108 #include "hard-reg-set.h"
109 #include "flags.h"
110 #include "function.h"
111 #include "expr.h"
112 #include "basic-block.h"
113 #include "except.h"
114 #include "tree-pass.h"
115 #include "timevar.h"
116 #include "target.h"
117 #include "vec.h"
118 #include "ira.h"
119 #include "lra-int.h"
120 #include "df.h"
121
122 /* Hard registers currently not available for allocation. It can
123 changed after some hard registers become not eliminable. */
124 HARD_REG_SET lra_no_alloc_regs;
125
126 static int get_new_reg_value (void);
127 static void expand_reg_info (void);
128 static void invalidate_insn_recog_data (int);
129 static int get_insn_freq (rtx);
130 static void invalidate_insn_data_regno_info (lra_insn_recog_data_t, rtx, int);
131
132 /* Expand all regno related info needed for LRA. */
133 static void
134 expand_reg_data (void)
135 {
136 resize_reg_info ();
137 expand_reg_info ();
138 ira_expand_reg_equiv ();
139 }
140
141 /* Create and return a new reg of ORIGINAL mode. If ORIGINAL is NULL
142 or of VOIDmode, use MD_MODE for the new reg. Initialize its
143 register class to RCLASS. Print message about assigning class
144 RCLASS containing new register name TITLE unless it is NULL. Use
145 attributes of ORIGINAL if it is a register. The created register
146 will have unique held value. */
147 rtx
148 lra_create_new_reg_with_unique_value (enum machine_mode md_mode, rtx original,
149 enum reg_class rclass, const char *title)
150 {
151 enum machine_mode mode;
152 rtx new_reg;
153
154 if (original == NULL_RTX || (mode = GET_MODE (original)) == VOIDmode)
155 mode = md_mode;
156 lra_assert (mode != VOIDmode);
157 new_reg = gen_reg_rtx (mode);
158 if (original == NULL_RTX || ! REG_P (original))
159 {
160 if (lra_dump_file != NULL)
161 fprintf (lra_dump_file, " Creating newreg=%i", REGNO (new_reg));
162 }
163 else
164 {
165 if (ORIGINAL_REGNO (original) >= FIRST_PSEUDO_REGISTER)
166 ORIGINAL_REGNO (new_reg) = ORIGINAL_REGNO (original);
167 REG_USERVAR_P (new_reg) = REG_USERVAR_P (original);
168 REG_POINTER (new_reg) = REG_POINTER (original);
169 REG_ATTRS (new_reg) = REG_ATTRS (original);
170 if (lra_dump_file != NULL)
171 fprintf (lra_dump_file, " Creating newreg=%i from oldreg=%i",
172 REGNO (new_reg), REGNO (original));
173 }
174 if (lra_dump_file != NULL)
175 {
176 if (title != NULL)
177 fprintf (lra_dump_file, ", assigning class %s to%s%s r%d",
178 reg_class_names[rclass], *title == '\0' ? "" : " ",
179 title, REGNO (new_reg));
180 fprintf (lra_dump_file, "\n");
181 }
182 expand_reg_data ();
183 setup_reg_classes (REGNO (new_reg), rclass, NO_REGS, rclass);
184 return new_reg;
185 }
186
187 /* Analogous to the previous function but also inherits value of
188 ORIGINAL. */
189 rtx
190 lra_create_new_reg (enum machine_mode md_mode, rtx original,
191 enum reg_class rclass, const char *title)
192 {
193 rtx new_reg;
194
195 new_reg
196 = lra_create_new_reg_with_unique_value (md_mode, original, rclass, title);
197 if (original != NULL_RTX && REG_P (original))
198 lra_reg_info[REGNO (new_reg)].val = lra_reg_info[REGNO (original)].val;
199 return new_reg;
200 }
201
202 /* Set up for REGNO unique hold value. */
203 void
204 lra_set_regno_unique_value (int regno)
205 {
206 lra_reg_info[regno].val = get_new_reg_value ();
207 }
208
209 /* Invalidate INSN related info used by LRA. */
210 void
211 lra_invalidate_insn_data (rtx insn)
212 {
213 lra_invalidate_insn_regno_info (insn);
214 invalidate_insn_recog_data (INSN_UID (insn));
215 }
216
217 /* Mark INSN deleted and invalidate the insn related info used by
218 LRA. */
219 void
220 lra_set_insn_deleted (rtx insn)
221 {
222 lra_invalidate_insn_data (insn);
223 SET_INSN_DELETED (insn);
224 }
225
226 /* Delete an unneeded INSN and any previous insns who sole purpose is
227 loading data that is dead in INSN. */
228 void
229 lra_delete_dead_insn (rtx insn)
230 {
231 rtx prev = prev_real_insn (insn);
232 rtx prev_dest;
233
234 /* If the previous insn sets a register that dies in our insn,
235 delete it too. */
236 if (prev && GET_CODE (PATTERN (prev)) == SET
237 && (prev_dest = SET_DEST (PATTERN (prev)), REG_P (prev_dest))
238 && reg_mentioned_p (prev_dest, PATTERN (insn))
239 && find_regno_note (insn, REG_DEAD, REGNO (prev_dest))
240 && ! side_effects_p (SET_SRC (PATTERN (prev))))
241 lra_delete_dead_insn (prev);
242
243 lra_set_insn_deleted (insn);
244 }
245
246 /* Target checks operands through operand predicates to recognize an
247 insn. We should have a special precaution to generate add insns
248 which are frequent results of elimination.
249
250 Emit insns for x = y + z. X can be used to store intermediate
251 values and should be not in Y and Z when we use X to store an
252 intermediate value. Y + Z should form [base] [+ index[ * scale]] [
253 + disp] where base and index are registers, disp and scale are
254 constants. Y should contain base if it is present, Z should
255 contain disp if any. index[*scale] can be part of Y or Z. */
256 void
257 lra_emit_add (rtx x, rtx y, rtx z)
258 {
259 int old;
260 rtx insn, last;
261 rtx a1, a2, base, index, disp, scale, index_scale;
262 bool ok_p;
263
264 insn = gen_add3_insn (x, y, z);
265 old = max_reg_num ();
266 if (insn != NULL_RTX)
267 emit_insn (insn);
268 else
269 {
270 disp = a2 = NULL_RTX;
271 if (GET_CODE (y) == PLUS)
272 {
273 a1 = XEXP (y, 0);
274 a2 = XEXP (y, 1);
275 disp = z;
276 }
277 else
278 {
279 a1 = y;
280 if (CONSTANT_P (z))
281 disp = z;
282 else
283 a2 = z;
284 }
285 index_scale = scale = NULL_RTX;
286 if (GET_CODE (a1) == MULT)
287 {
288 index_scale = a1;
289 index = XEXP (a1, 0);
290 scale = XEXP (a1, 1);
291 base = a2;
292 }
293 else if (a2 != NULL_RTX && GET_CODE (a2) == MULT)
294 {
295 index_scale = a2;
296 index = XEXP (a2, 0);
297 scale = XEXP (a2, 1);
298 base = a1;
299 }
300 else
301 {
302 base = a1;
303 index = a2;
304 }
305 if (! REG_P (base)
306 || (index != NULL_RTX && ! REG_P (index))
307 || (disp != NULL_RTX && ! CONSTANT_P (disp))
308 || (scale != NULL_RTX && ! CONSTANT_P (scale)))
309 {
310 /* Its is not an address generation. Probably we have no 3 op
311 add. Last chance is to use 2-op add insn. */
312 lra_assert (x != y && x != z);
313 emit_move_insn (x, z);
314 insn = gen_add2_insn (x, y);
315 emit_insn (insn);
316 }
317 else
318 {
319 if (index_scale == NULL_RTX)
320 index_scale = index;
321 if (disp == NULL_RTX)
322 {
323 /* Generate x = index_scale; x = x + base. */
324 lra_assert (index_scale != NULL_RTX && base != NULL_RTX);
325 emit_move_insn (x, index_scale);
326 insn = gen_add2_insn (x, base);
327 emit_insn (insn);
328 }
329 else if (scale == NULL_RTX)
330 {
331 /* Try x = base + disp. */
332 lra_assert (base != NULL_RTX);
333 last = get_last_insn ();
334 insn = emit_move_insn (x, gen_rtx_PLUS (GET_MODE (base),
335 base, disp));
336 if (recog_memoized (insn) < 0)
337 {
338 delete_insns_since (last);
339 /* Generate x = disp; x = x + base. */
340 emit_move_insn (x, disp);
341 insn = gen_add2_insn (x, base);
342 emit_insn (insn);
343 }
344 /* Generate x = x + index. */
345 if (index != NULL_RTX)
346 {
347 insn = gen_add2_insn (x, index);
348 emit_insn (insn);
349 }
350 }
351 else
352 {
353 /* Try x = index_scale; x = x + disp; x = x + base. */
354 last = get_last_insn ();
355 insn = emit_move_insn (x, index_scale);
356 ok_p = false;
357 if (recog_memoized (insn) >= 0)
358 {
359 insn = gen_add2_insn (x, disp);
360 if (insn != NULL_RTX)
361 {
362 emit_insn (insn);
363 insn = gen_add2_insn (x, disp);
364 if (insn != NULL_RTX)
365 {
366 emit_insn (insn);
367 ok_p = true;
368 }
369 }
370 }
371 if (! ok_p)
372 {
373 delete_insns_since (last);
374 /* Generate x = disp; x = x + base; x = x + index_scale. */
375 emit_move_insn (x, disp);
376 insn = gen_add2_insn (x, base);
377 emit_insn (insn);
378 insn = gen_add2_insn (x, index_scale);
379 emit_insn (insn);
380 }
381 }
382 }
383 }
384 /* Functions emit_... can create pseudos -- so expand the pseudo
385 data. */
386 if (old != max_reg_num ())
387 expand_reg_data ();
388 }
389
390 /* The number of emitted reload insns so far. */
391 int lra_curr_reload_num;
392
393 /* Emit x := y, processing special case when y = u + v or y = u + v *
394 scale + w through emit_add (Y can be an address which is base +
395 index reg * scale + displacement in general case). X may be used
396 as intermediate result therefore it should be not in Y. */
397 void
398 lra_emit_move (rtx x, rtx y)
399 {
400 int old;
401
402 if (GET_CODE (y) != PLUS)
403 {
404 if (rtx_equal_p (x, y))
405 return;
406 old = max_reg_num ();
407 emit_move_insn (x, y);
408 if (REG_P (x))
409 lra_reg_info[ORIGINAL_REGNO (x)].last_reload = ++lra_curr_reload_num;
410 /* Function emit_move can create pseudos -- so expand the pseudo
411 data. */
412 if (old != max_reg_num ())
413 expand_reg_data ();
414 return;
415 }
416 lra_emit_add (x, XEXP (y, 0), XEXP (y, 1));
417 }
418
419 /* Update insn operands which are duplication of operands whose
420 numbers are in array of NOPS (with end marker -1). The insn is
421 represented by its LRA internal representation ID. */
422 void
423 lra_update_dups (lra_insn_recog_data_t id, signed char *nops)
424 {
425 int i, j, nop;
426 struct lra_static_insn_data *static_id = id->insn_static_data;
427
428 for (i = 0; i < static_id->n_dups; i++)
429 for (j = 0; (nop = nops[j]) >= 0; j++)
430 if (static_id->dup_num[i] == nop)
431 *id->dup_loc[i] = *id->operand_loc[nop];
432 }
433
434 \f
435
436 /* This page contains code dealing with info about registers in the
437 insns. */
438
439 /* Pools for insn reg info. */
440 static alloc_pool insn_reg_pool;
441
442 /* Initiate pool for insn reg info. */
443 static void
444 init_insn_regs (void)
445 {
446 insn_reg_pool
447 = create_alloc_pool ("insn regs", sizeof (struct lra_insn_reg), 100);
448 }
449
450 /* Create LRA insn related info about referenced REGNO with TYPE
451 (in/out/inout), biggest reference mode MODE, flag that it is
452 reference through subreg (SUBREG_P), flag that is early clobbered
453 in the insn (EARLY_CLOBBER), and reference to the next insn reg
454 info (NEXT). */
455 static struct lra_insn_reg *
456 new_insn_reg (int regno, enum op_type type, enum machine_mode mode,
457 bool subreg_p, bool early_clobber, struct lra_insn_reg *next)
458 {
459 struct lra_insn_reg *ir;
460
461 ir = (struct lra_insn_reg *) pool_alloc (insn_reg_pool);
462 ir->type = type;
463 ir->biggest_mode = mode;
464 ir->subreg_p = subreg_p;
465 ir->early_clobber = early_clobber;
466 ir->regno = regno;
467 ir->next = next;
468 return ir;
469 }
470
471 /* Free insn reg info IR. */
472 static void
473 free_insn_reg (struct lra_insn_reg *ir)
474 {
475 pool_free (insn_reg_pool, ir);
476 }
477
478 /* Free insn reg info list IR. */
479 static void
480 free_insn_regs (struct lra_insn_reg *ir)
481 {
482 struct lra_insn_reg *next_ir;
483
484 for (; ir != NULL; ir = next_ir)
485 {
486 next_ir = ir->next;
487 free_insn_reg (ir);
488 }
489 }
490
491 /* Finish pool for insn reg info. */
492 static void
493 finish_insn_regs (void)
494 {
495 free_alloc_pool (insn_reg_pool);
496 }
497
498 \f
499
500 /* This page contains code dealing LRA insn info (or in other words
501 LRA internal insn representation). */
502
503 struct target_lra_int default_target_lra_int;
504 #if SWITCHABLE_TARGET
505 struct target_lra_int *this_target_lra_int = &default_target_lra_int;
506 #endif
507
508 /* Map INSN_CODE -> the static insn data. This info is valid during
509 all translation unit. */
510 struct lra_static_insn_data *insn_code_data[LAST_INSN_CODE];
511
512 /* Debug insns are represented as a special insn with one input
513 operand which is RTL expression in var_location. */
514
515 /* The following data are used as static insn operand data for all
516 debug insns. If structure lra_operand_data is changed, the
517 initializer should be changed too. */
518 static struct lra_operand_data debug_operand_data =
519 {
520 NULL, /* alternative */
521 VOIDmode, /* We are not interesting in the operand mode. */
522 OP_IN,
523 0, 0, 0, 0
524 };
525
526 /* The following data are used as static insn data for all debug
527 insns. If structure lra_static_insn_data is changed, the
528 initializer should be changed too. */
529 static struct lra_static_insn_data debug_insn_static_data =
530 {
531 &debug_operand_data,
532 0, /* Duplication operands #. */
533 -1, /* Commutative operand #. */
534 1, /* Operands #. There is only one operand which is debug RTL
535 expression. */
536 0, /* Duplications #. */
537 0, /* Alternatives #. We are not interesting in alternatives
538 because we does not proceed debug_insns for reloads. */
539 NULL, /* Hard registers referenced in machine description. */
540 NULL /* Descriptions of operands in alternatives. */
541 };
542
543 /* Called once per compiler work to initialize some LRA data related
544 to insns. */
545 static void
546 init_insn_code_data_once (void)
547 {
548 memset (insn_code_data, 0, sizeof (insn_code_data));
549 memset (op_alt_data, 0, sizeof (op_alt_data));
550 }
551
552 /* Called once per compiler work to finalize some LRA data related to
553 insns. */
554 static void
555 finish_insn_code_data_once (void)
556 {
557 int i;
558
559 for (i = 0; i < LAST_INSN_CODE; i++)
560 {
561 if (insn_code_data[i] != NULL)
562 free (insn_code_data[i]);
563 if (op_alt_data[i] != NULL)
564 free (op_alt_data[i]);
565 }
566 }
567
568 /* Initialize LRA info about operands in insn alternatives. */
569 static void
570 init_op_alt_data (void)
571 {
572 int i;
573
574 for (i = 0; i < LAST_INSN_CODE; i++)
575 if (op_alt_data[i] != NULL)
576 {
577 free (op_alt_data[i]);
578 op_alt_data[i] = NULL;
579 }
580 }
581
582 /* Return static insn data, allocate and setup if necessary. Although
583 dup_num is static data (it depends only on icode), to set it up we
584 need to extract insn first. So recog_data should be valid for
585 normal insn (ICODE >= 0) before the call. */
586 static struct lra_static_insn_data *
587 get_static_insn_data (int icode, int nop, int ndup, int nalt)
588 {
589 struct lra_static_insn_data *data;
590 size_t n_bytes;
591
592 lra_assert (icode < LAST_INSN_CODE);
593 if (icode >= 0 && (data = insn_code_data[icode]) != NULL)
594 return data;
595 lra_assert (nop >= 0 && ndup >= 0 && nalt >= 0);
596 n_bytes = sizeof (struct lra_static_insn_data)
597 + sizeof (struct lra_operand_data) * nop
598 + sizeof (int) * ndup;
599 data = XNEWVAR (struct lra_static_insn_data, n_bytes);
600 data->n_operands = nop;
601 data->n_dups = ndup;
602 data->n_alternatives = nalt;
603 data->operand = ((struct lra_operand_data *)
604 ((char *) data + sizeof (struct lra_static_insn_data)));
605 data->dup_num = ((int *) ((char *) data->operand
606 + sizeof (struct lra_operand_data) * nop));
607 if (icode >= 0)
608 {
609 int i;
610
611 insn_code_data[icode] = data;
612 for (i = 0; i < nop; i++)
613 {
614 data->operand[i].constraint
615 = insn_data[icode].operand[i].constraint;
616 data->operand[i].mode = insn_data[icode].operand[i].mode;
617 data->operand[i].strict_low = insn_data[icode].operand[i].strict_low;
618 data->operand[i].is_operator
619 = insn_data[icode].operand[i].is_operator;
620 data->operand[i].type
621 = (data->operand[i].constraint[0] == '=' ? OP_OUT
622 : data->operand[i].constraint[0] == '+' ? OP_INOUT
623 : OP_IN);
624 data->operand[i].is_address = false;
625 }
626 for (i = 0; i < ndup; i++)
627 data->dup_num[i] = recog_data.dup_num[i];
628 }
629 return data;
630 }
631
632 /* The current length of the following array. */
633 int lra_insn_recog_data_len;
634
635 /* Map INSN_UID -> the insn recog data (NULL if unknown). */
636 lra_insn_recog_data_t *lra_insn_recog_data;
637
638 /* Initialize LRA data about insns. */
639 static void
640 init_insn_recog_data (void)
641 {
642 lra_insn_recog_data_len = 0;
643 lra_insn_recog_data = NULL;
644 init_insn_regs ();
645 }
646
647 /* Expand, if necessary, LRA data about insns. */
648 static void
649 check_and_expand_insn_recog_data (int index)
650 {
651 int i, old;
652
653 if (lra_insn_recog_data_len > index)
654 return;
655 old = lra_insn_recog_data_len;
656 lra_insn_recog_data_len = index * 3 / 2 + 1;
657 lra_insn_recog_data = XRESIZEVEC (lra_insn_recog_data_t,
658 lra_insn_recog_data,
659 lra_insn_recog_data_len);
660 for (i = old; i < lra_insn_recog_data_len; i++)
661 lra_insn_recog_data[i] = NULL;
662 }
663
664 /* Finish LRA DATA about insn. */
665 static void
666 free_insn_recog_data (lra_insn_recog_data_t data)
667 {
668 if (data->operand_loc != NULL)
669 free (data->operand_loc);
670 if (data->dup_loc != NULL)
671 free (data->dup_loc);
672 if (data->arg_hard_regs != NULL)
673 free (data->arg_hard_regs);
674 if (HAVE_ATTR_enabled && data->alternative_enabled_p != NULL)
675 free (data->alternative_enabled_p);
676 if (data->icode < 0 && NONDEBUG_INSN_P (data->insn))
677 {
678 if (data->insn_static_data->operand_alternative != NULL)
679 free (data->insn_static_data->operand_alternative);
680 free_insn_regs (data->insn_static_data->hard_regs);
681 free (data->insn_static_data);
682 }
683 free_insn_regs (data->regs);
684 data->regs = NULL;
685 free (data);
686 }
687
688 /* Finish LRA data about all insns. */
689 static void
690 finish_insn_recog_data (void)
691 {
692 int i;
693 lra_insn_recog_data_t data;
694
695 for (i = 0; i < lra_insn_recog_data_len; i++)
696 if ((data = lra_insn_recog_data[i]) != NULL)
697 free_insn_recog_data (data);
698 finish_insn_regs ();
699 free (lra_insn_recog_data);
700 }
701
702 /* Setup info about operands in alternatives of LRA DATA of insn. */
703 static void
704 setup_operand_alternative (lra_insn_recog_data_t data)
705 {
706 int i, nop, nalt;
707 int icode = data->icode;
708 struct lra_static_insn_data *static_data = data->insn_static_data;
709
710 if (icode >= 0
711 && (static_data->operand_alternative = op_alt_data[icode]) != NULL)
712 return;
713 static_data->commutative = -1;
714 nop = static_data->n_operands;
715 if (nop == 0)
716 {
717 static_data->operand_alternative = NULL;
718 return;
719 }
720 nalt = static_data->n_alternatives;
721 static_data->operand_alternative = XNEWVEC (struct operand_alternative,
722 nalt * nop);
723 memset (static_data->operand_alternative, 0,
724 nalt * nop * sizeof (struct operand_alternative));
725 if (icode >= 0)
726 op_alt_data[icode] = static_data->operand_alternative;
727 for (i = 0; i < nop; i++)
728 {
729 int j;
730 struct operand_alternative *op_alt_start, *op_alt;
731 const char *p = static_data->operand[i].constraint;
732
733 static_data->operand[i].early_clobber = 0;
734 op_alt_start = &static_data->operand_alternative[i];
735
736 for (j = 0; j < nalt; j++)
737 {
738 op_alt = op_alt_start + j * nop;
739 op_alt->cl = NO_REGS;
740 op_alt->constraint = p;
741 op_alt->matches = -1;
742 op_alt->matched = -1;
743
744 if (*p == '\0' || *p == ',')
745 {
746 op_alt->anything_ok = 1;
747 continue;
748 }
749
750 for (;;)
751 {
752 char c = *p;
753 if (c == '#')
754 do
755 c = *++p;
756 while (c != ',' && c != '\0');
757 if (c == ',' || c == '\0')
758 {
759 p++;
760 break;
761 }
762
763 switch (c)
764 {
765 case '=': case '+': case '*':
766 case 'E': case 'F': case 'G': case 'H':
767 case 's': case 'i': case 'n':
768 case 'I': case 'J': case 'K': case 'L':
769 case 'M': case 'N': case 'O': case 'P':
770 /* These don't say anything we care about. */
771 break;
772
773 case '%':
774 /* We currently only support one commutative pair of
775 operands. */
776 if (static_data->commutative < 0)
777 static_data->commutative = i;
778 else
779 lra_assert (data->icode < 0); /* Asm */
780
781 /* The last operand should not be marked
782 commutative. */
783 lra_assert (i != nop - 1);
784 break;
785
786 case '?':
787 op_alt->reject += LRA_LOSER_COST_FACTOR;
788 break;
789 case '!':
790 op_alt->reject += LRA_MAX_REJECT;
791 break;
792 case '&':
793 op_alt->earlyclobber = 1;
794 static_data->operand[i].early_clobber = 1;
795 break;
796
797 case '0': case '1': case '2': case '3': case '4':
798 case '5': case '6': case '7': case '8': case '9':
799 {
800 char *end;
801 op_alt->matches = strtoul (p, &end, 10);
802 static_data->operand_alternative
803 [j * nop + op_alt->matches].matched = i;
804 p = end;
805 }
806 continue;
807
808 case TARGET_MEM_CONSTRAINT:
809 op_alt->memory_ok = 1;
810 break;
811 case '<':
812 op_alt->decmem_ok = 1;
813 break;
814 case '>':
815 op_alt->incmem_ok = 1;
816 break;
817 case 'V':
818 op_alt->nonoffmem_ok = 1;
819 break;
820 case 'o':
821 op_alt->offmem_ok = 1;
822 break;
823 case 'X':
824 op_alt->anything_ok = 1;
825 break;
826
827 case 'p':
828 static_data->operand[i].is_address = true;
829 op_alt->is_address = 1;
830 op_alt->cl = (reg_class_subunion[(int) op_alt->cl]
831 [(int) base_reg_class (VOIDmode,
832 ADDR_SPACE_GENERIC,
833 ADDRESS, SCRATCH)]);
834 break;
835
836 case 'g':
837 case 'r':
838 op_alt->cl =
839 reg_class_subunion[(int) op_alt->cl][(int) GENERAL_REGS];
840 break;
841
842 default:
843 if (EXTRA_MEMORY_CONSTRAINT (c, p))
844 {
845 op_alt->memory_ok = 1;
846 break;
847 }
848 if (EXTRA_ADDRESS_CONSTRAINT (c, p))
849 {
850 static_data->operand[i].is_address = true;
851 op_alt->is_address = 1;
852 op_alt->cl
853 = (reg_class_subunion
854 [(int) op_alt->cl]
855 [(int) base_reg_class (VOIDmode, ADDR_SPACE_GENERIC,
856 ADDRESS, SCRATCH)]);
857 break;
858 }
859
860 op_alt->cl
861 = (reg_class_subunion
862 [(int) op_alt->cl]
863 [(int)
864 REG_CLASS_FROM_CONSTRAINT ((unsigned char) c, p)]);
865 break;
866 }
867 p += CONSTRAINT_LEN (c, p);
868 }
869 }
870 }
871 }
872
873 /* Recursively process X and collect info about registers, which are
874 not the insn operands, in X with TYPE (in/out/inout) and flag that
875 it is early clobbered in the insn (EARLY_CLOBBER) and add the info
876 to LIST. X is a part of insn given by DATA. Return the result
877 list. */
878 static struct lra_insn_reg *
879 collect_non_operand_hard_regs (rtx *x, lra_insn_recog_data_t data,
880 struct lra_insn_reg *list,
881 enum op_type type, bool early_clobber)
882 {
883 int i, j, regno, last;
884 bool subreg_p;
885 enum machine_mode mode;
886 struct lra_insn_reg *curr;
887 rtx op = *x;
888 enum rtx_code code = GET_CODE (op);
889 const char *fmt = GET_RTX_FORMAT (code);
890
891 for (i = 0; i < data->insn_static_data->n_operands; i++)
892 if (x == data->operand_loc[i])
893 /* It is an operand loc. Stop here. */
894 return list;
895 for (i = 0; i < data->insn_static_data->n_dups; i++)
896 if (x == data->dup_loc[i])
897 /* It is a dup loc. Stop here. */
898 return list;
899 mode = GET_MODE (op);
900 subreg_p = false;
901 if (code == SUBREG)
902 {
903 op = SUBREG_REG (op);
904 code = GET_CODE (op);
905 if (GET_MODE_SIZE (mode) < GET_MODE_SIZE (GET_MODE (op)))
906 {
907 mode = GET_MODE (op);
908 if (GET_MODE_SIZE (mode) > REGMODE_NATURAL_SIZE (mode))
909 subreg_p = true;
910 }
911 }
912 if (REG_P (op))
913 {
914 if ((regno = REGNO (op)) >= FIRST_PSEUDO_REGISTER)
915 return list;
916 for (last = regno + hard_regno_nregs[regno][mode];
917 regno < last;
918 regno++)
919 if (! TEST_HARD_REG_BIT (lra_no_alloc_regs, regno))
920 {
921 for (curr = list; curr != NULL; curr = curr->next)
922 if (curr->regno == regno && curr->subreg_p == subreg_p
923 && curr->biggest_mode == mode)
924 {
925 if (curr->type != type)
926 curr->type = OP_INOUT;
927 if (curr->early_clobber != early_clobber)
928 curr->early_clobber = true;
929 break;
930 }
931 if (curr == NULL)
932 {
933 /* This is a new hard regno or the info can not be
934 integrated into the found structure. */
935 #ifdef STACK_REGS
936 early_clobber
937 = (early_clobber
938 /* This clobber is to inform popping floating
939 point stack only. */
940 && ! (FIRST_STACK_REG <= regno
941 && regno <= LAST_STACK_REG));
942 #endif
943 list = new_insn_reg (regno, type, mode, subreg_p,
944 early_clobber, list);
945 }
946 }
947 return list;
948 }
949 switch (code)
950 {
951 case SET:
952 list = collect_non_operand_hard_regs (&SET_DEST (op), data,
953 list, OP_OUT, false);
954 list = collect_non_operand_hard_regs (&SET_SRC (op), data,
955 list, OP_IN, false);
956 break;
957 case CLOBBER:
958 /* We treat clobber of non-operand hard registers as early
959 clobber (the behavior is expected from asm). */
960 list = collect_non_operand_hard_regs (&XEXP (op, 0), data,
961 list, OP_OUT, true);
962 break;
963 case PRE_INC: case PRE_DEC: case POST_INC: case POST_DEC:
964 list = collect_non_operand_hard_regs (&XEXP (op, 0), data,
965 list, OP_INOUT, false);
966 break;
967 case PRE_MODIFY: case POST_MODIFY:
968 list = collect_non_operand_hard_regs (&XEXP (op, 0), data,
969 list, OP_INOUT, false);
970 list = collect_non_operand_hard_regs (&XEXP (op, 1), data,
971 list, OP_IN, false);
972 break;
973 default:
974 fmt = GET_RTX_FORMAT (code);
975 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
976 {
977 if (fmt[i] == 'e')
978 list = collect_non_operand_hard_regs (&XEXP (op, i), data,
979 list, OP_IN, false);
980 else if (fmt[i] == 'E')
981 for (j = XVECLEN (op, i) - 1; j >= 0; j--)
982 list = collect_non_operand_hard_regs (&XVECEXP (op, i, j), data,
983 list, OP_IN, false);
984 }
985 }
986 return list;
987 }
988
989 /* Set up and return info about INSN. Set up the info if it is not set up
990 yet. */
991 lra_insn_recog_data_t
992 lra_set_insn_recog_data (rtx insn)
993 {
994 lra_insn_recog_data_t data;
995 int i, n, icode;
996 rtx **locs;
997 unsigned int uid = INSN_UID (insn);
998 struct lra_static_insn_data *insn_static_data;
999
1000 check_and_expand_insn_recog_data (uid);
1001 if (DEBUG_INSN_P (insn))
1002 icode = -1;
1003 else
1004 {
1005 icode = INSN_CODE (insn);
1006 if (icode < 0)
1007 /* It might be a new simple insn which is not recognized yet. */
1008 INSN_CODE (insn) = icode = recog_memoized (insn);
1009 }
1010 data = XNEW (struct lra_insn_recog_data);
1011 lra_insn_recog_data[uid] = data;
1012 data->insn = insn;
1013 data->used_insn_alternative = -1;
1014 data->icode = icode;
1015 data->regs = NULL;
1016 if (DEBUG_INSN_P (insn))
1017 {
1018 data->insn_static_data = &debug_insn_static_data;
1019 data->dup_loc = NULL;
1020 data->arg_hard_regs = NULL;
1021 data->alternative_enabled_p = NULL;
1022 data->operand_loc = XNEWVEC (rtx *, 1);
1023 data->operand_loc[0] = &INSN_VAR_LOCATION_LOC (insn);
1024 return data;
1025 }
1026 if (icode < 0)
1027 {
1028 int nop;
1029 enum machine_mode operand_mode[MAX_RECOG_OPERANDS];
1030 const char *constraints[MAX_RECOG_OPERANDS];
1031
1032 nop = asm_noperands (PATTERN (insn));
1033 data->operand_loc = data->dup_loc = NULL;
1034 if (nop < 0)
1035 /* Its is a special insn like USE or CLOBBER. */
1036 data->insn_static_data = insn_static_data
1037 = get_static_insn_data (-1, 0, 0, 1);
1038 else
1039 {
1040 /* expand_asm_operands makes sure there aren't too many
1041 operands. */
1042 lra_assert (nop <= MAX_RECOG_OPERANDS);
1043 if (nop != 0)
1044 data->operand_loc = XNEWVEC (rtx *, nop);
1045 /* Now get the operand values and constraints out of the
1046 insn. */
1047 decode_asm_operands (PATTERN (insn), NULL,
1048 data->operand_loc,
1049 constraints, operand_mode, NULL);
1050 n = 1;
1051 if (nop > 0)
1052 {
1053 const char *p = recog_data.constraints[0];
1054
1055 for (p = constraints[0]; *p; p++)
1056 n += *p == ',';
1057 }
1058 data->insn_static_data = insn_static_data
1059 = get_static_insn_data (-1, nop, 0, n);
1060 for (i = 0; i < nop; i++)
1061 {
1062 insn_static_data->operand[i].mode = operand_mode[i];
1063 insn_static_data->operand[i].constraint = constraints[i];
1064 insn_static_data->operand[i].strict_low = false;
1065 insn_static_data->operand[i].is_operator = false;
1066 insn_static_data->operand[i].is_address = false;
1067 }
1068 }
1069 for (i = 0; i < insn_static_data->n_operands; i++)
1070 insn_static_data->operand[i].type
1071 = (insn_static_data->operand[i].constraint[0] == '=' ? OP_OUT
1072 : insn_static_data->operand[i].constraint[0] == '+' ? OP_INOUT
1073 : OP_IN);
1074 data->alternative_enabled_p = NULL;
1075 }
1076 else
1077 {
1078 insn_extract (insn);
1079 data->insn_static_data = insn_static_data
1080 = get_static_insn_data (icode, insn_data[icode].n_operands,
1081 insn_data[icode].n_dups,
1082 insn_data[icode].n_alternatives);
1083 n = insn_static_data->n_operands;
1084 if (n == 0)
1085 locs = NULL;
1086 else
1087 {
1088 locs = XNEWVEC (rtx *, n);
1089 memcpy (locs, recog_data.operand_loc, n * sizeof (rtx *));
1090 }
1091 data->operand_loc = locs;
1092 n = insn_static_data->n_dups;
1093 if (n == 0)
1094 locs = NULL;
1095 else
1096 {
1097 locs = XNEWVEC (rtx *, n);
1098 memcpy (locs, recog_data.dup_loc, n * sizeof (rtx *));
1099 }
1100 data->dup_loc = locs;
1101 if (HAVE_ATTR_enabled)
1102 {
1103 bool *bp;
1104
1105 n = insn_static_data->n_alternatives;
1106 lra_assert (n >= 0);
1107 data->alternative_enabled_p = bp = XNEWVEC (bool, n);
1108 /* Cache the insn because we don't want to call extract_insn
1109 from get_attr_enabled as extract_insn modifies
1110 which_alternative. The attribute enabled should not depend
1111 on insn operands, operand modes, operand types, and operand
1112 constraints. It should depend on the architecture. If it
1113 is not true, we should rewrite this file code to use
1114 extract_insn instead of less expensive insn_extract. */
1115 recog_data.insn = insn;
1116 for (i = 0; i < n; i++)
1117 {
1118 which_alternative = i;
1119 bp[i] = get_attr_enabled (insn);
1120 }
1121 }
1122 }
1123 if (GET_CODE (PATTERN (insn)) == CLOBBER || GET_CODE (PATTERN (insn)) == USE)
1124 insn_static_data->hard_regs = NULL;
1125 else
1126 insn_static_data->hard_regs
1127 = collect_non_operand_hard_regs (&PATTERN (insn), data,
1128 NULL, OP_IN, false);
1129 setup_operand_alternative (data);
1130 data->arg_hard_regs = NULL;
1131 if (CALL_P (insn))
1132 {
1133 rtx link;
1134 int n_hard_regs, regno, arg_hard_regs[FIRST_PSEUDO_REGISTER];
1135
1136 n_hard_regs = 0;
1137 /* Finding implicit hard register usage. We believe it will be
1138 not changed whatever transformations are used. Call insns
1139 are such example. */
1140 for (link = CALL_INSN_FUNCTION_USAGE (insn);
1141 link != NULL_RTX;
1142 link = XEXP (link, 1))
1143 if (GET_CODE (XEXP (link, 0)) == USE
1144 && REG_P (XEXP (XEXP (link, 0), 0)))
1145 {
1146 regno = REGNO (XEXP (XEXP (link, 0), 0));
1147 lra_assert (regno < FIRST_PSEUDO_REGISTER);
1148 /* It is an argument register. */
1149 for (i = (hard_regno_nregs
1150 [regno][GET_MODE (XEXP (XEXP (link, 0), 0))]) - 1;
1151 i >= 0;
1152 i--)
1153 arg_hard_regs[n_hard_regs++] = regno + i;
1154 }
1155 if (n_hard_regs != 0)
1156 {
1157 arg_hard_regs[n_hard_regs++] = -1;
1158 data->arg_hard_regs = XNEWVEC (int, n_hard_regs);
1159 memcpy (data->arg_hard_regs, arg_hard_regs,
1160 sizeof (int) * n_hard_regs);
1161 }
1162 }
1163 /* Some output operand can be recognized only from the context not
1164 from the constraints which are empty in this case. Call insn may
1165 contain a hard register in set destination with empty constraint
1166 and extract_insn treats them as an input. */
1167 for (i = 0; i < insn_static_data->n_operands; i++)
1168 {
1169 int j;
1170 rtx pat, set;
1171 struct lra_operand_data *operand = &insn_static_data->operand[i];
1172
1173 /* ??? Should we treat 'X' the same way. It looks to me that
1174 'X' means anything and empty constraint means we do not
1175 care. */
1176 if (operand->type != OP_IN || *operand->constraint != '\0'
1177 || operand->is_operator)
1178 continue;
1179 pat = PATTERN (insn);
1180 if (GET_CODE (pat) == SET)
1181 {
1182 if (data->operand_loc[i] != &SET_DEST (pat))
1183 continue;
1184 }
1185 else if (GET_CODE (pat) == PARALLEL)
1186 {
1187 for (j = XVECLEN (pat, 0) - 1; j >= 0; j--)
1188 {
1189 set = XVECEXP (PATTERN (insn), 0, j);
1190 if (GET_CODE (set) == SET
1191 && &SET_DEST (set) == data->operand_loc[i])
1192 break;
1193 }
1194 if (j < 0)
1195 continue;
1196 }
1197 else
1198 continue;
1199 operand->type = OP_OUT;
1200 }
1201 return data;
1202 }
1203
1204 /* Return info about insn give by UID. The info should be already set
1205 up. */
1206 static lra_insn_recog_data_t
1207 get_insn_recog_data_by_uid (int uid)
1208 {
1209 lra_insn_recog_data_t data;
1210
1211 data = lra_insn_recog_data[uid];
1212 lra_assert (data != NULL);
1213 return data;
1214 }
1215
1216 /* Invalidate all info about insn given by its UID. */
1217 static void
1218 invalidate_insn_recog_data (int uid)
1219 {
1220 lra_insn_recog_data_t data;
1221
1222 data = lra_insn_recog_data[uid];
1223 lra_assert (data != NULL);
1224 free_insn_recog_data (data);
1225 lra_insn_recog_data[uid] = NULL;
1226 }
1227
1228 /* Update all the insn info about INSN. It is usually called when
1229 something in the insn was changed. Return the updated info. */
1230 lra_insn_recog_data_t
1231 lra_update_insn_recog_data (rtx insn)
1232 {
1233 lra_insn_recog_data_t data;
1234 int n;
1235 unsigned int uid = INSN_UID (insn);
1236 struct lra_static_insn_data *insn_static_data;
1237
1238 check_and_expand_insn_recog_data (uid);
1239 if ((data = lra_insn_recog_data[uid]) != NULL
1240 && data->icode != INSN_CODE (insn))
1241 {
1242 invalidate_insn_data_regno_info (data, insn, get_insn_freq (insn));
1243 invalidate_insn_recog_data (uid);
1244 data = NULL;
1245 }
1246 if (data == NULL)
1247 return lra_get_insn_recog_data (insn);
1248 insn_static_data = data->insn_static_data;
1249 data->used_insn_alternative = -1;
1250 if (DEBUG_INSN_P (insn))
1251 return data;
1252 if (data->icode < 0)
1253 {
1254 int nop;
1255 enum machine_mode operand_mode[MAX_RECOG_OPERANDS];
1256 const char *constraints[MAX_RECOG_OPERANDS];
1257
1258 nop = asm_noperands (PATTERN (insn));
1259 if (nop >= 0)
1260 {
1261 lra_assert (nop == data->insn_static_data->n_operands);
1262 /* Now get the operand values and constraints out of the
1263 insn. */
1264 decode_asm_operands (PATTERN (insn), NULL,
1265 data->operand_loc,
1266 constraints, operand_mode, NULL);
1267 #ifdef ENABLE_CHECKING
1268 {
1269 int i;
1270
1271 for (i = 0; i < nop; i++)
1272 lra_assert
1273 (insn_static_data->operand[i].mode == operand_mode[i]
1274 && insn_static_data->operand[i].constraint == constraints[i]
1275 && ! insn_static_data->operand[i].is_operator);
1276 }
1277 #endif
1278 }
1279 #ifdef ENABLE_CHECKING
1280 {
1281 int i;
1282
1283 for (i = 0; i < insn_static_data->n_operands; i++)
1284 lra_assert
1285 (insn_static_data->operand[i].type
1286 == (insn_static_data->operand[i].constraint[0] == '=' ? OP_OUT
1287 : insn_static_data->operand[i].constraint[0] == '+' ? OP_INOUT
1288 : OP_IN));
1289 }
1290 #endif
1291 }
1292 else
1293 {
1294 insn_extract (insn);
1295 n = insn_static_data->n_operands;
1296 if (n != 0)
1297 memcpy (data->operand_loc, recog_data.operand_loc, n * sizeof (rtx *));
1298 n = insn_static_data->n_dups;
1299 if (n != 0)
1300 memcpy (data->dup_loc, recog_data.dup_loc, n * sizeof (rtx *));
1301 #if HAVE_ATTR_enabled
1302 #ifdef ENABLE_CHECKING
1303 {
1304 int i;
1305 bool *bp;
1306
1307 n = insn_static_data->n_alternatives;
1308 bp = data->alternative_enabled_p;
1309 lra_assert (n >= 0 && bp != NULL);
1310 /* Cache the insn to prevent extract_insn call from
1311 get_attr_enabled. */
1312 recog_data.insn = insn;
1313 for (i = 0; i < n; i++)
1314 {
1315 which_alternative = i;
1316 lra_assert (bp[i] == get_attr_enabled (insn));
1317 }
1318 }
1319 #endif
1320 #endif
1321 }
1322 return data;
1323 }
1324
1325 /* Set up that INSN is using alternative ALT now. */
1326 void
1327 lra_set_used_insn_alternative (rtx insn, int alt)
1328 {
1329 lra_insn_recog_data_t data;
1330
1331 data = lra_get_insn_recog_data (insn);
1332 data->used_insn_alternative = alt;
1333 }
1334
1335 /* Set up that insn with UID is using alternative ALT now. The insn
1336 info should be already set up. */
1337 void
1338 lra_set_used_insn_alternative_by_uid (int uid, int alt)
1339 {
1340 lra_insn_recog_data_t data;
1341
1342 check_and_expand_insn_recog_data (uid);
1343 data = lra_insn_recog_data[uid];
1344 lra_assert (data != NULL);
1345 data->used_insn_alternative = alt;
1346 }
1347
1348 \f
1349
1350 /* This page contains code dealing with common register info and
1351 pseudo copies. */
1352
1353 /* The size of the following array. */
1354 static int reg_info_size;
1355 /* Common info about each register. */
1356 struct lra_reg *lra_reg_info;
1357
1358 /* Last register value. */
1359 static int last_reg_value;
1360
1361 /* Return new register value. */
1362 static int
1363 get_new_reg_value (void)
1364 {
1365 return ++last_reg_value;
1366 }
1367
1368 /* Pools for copies. */
1369 static alloc_pool copy_pool;
1370
1371 DEF_VEC_P(lra_copy_t);
1372 DEF_VEC_ALLOC_P(lra_copy_t, heap);
1373
1374 /* Vec referring to pseudo copies. */
1375 static VEC(lra_copy_t,heap) *copy_vec;
1376
1377 /* Initialize I-th element of lra_reg_info. */
1378 static inline void
1379 initialize_lra_reg_info_element (int i)
1380 {
1381 bitmap_initialize (&lra_reg_info[i].insn_bitmap, &reg_obstack);
1382 #ifdef STACK_REGS
1383 lra_reg_info[i].no_stack_p = false;
1384 #endif
1385 CLEAR_HARD_REG_SET (lra_reg_info[i].conflict_hard_regs);
1386 lra_reg_info[i].preferred_hard_regno1 = -1;
1387 lra_reg_info[i].preferred_hard_regno2 = -1;
1388 lra_reg_info[i].preferred_hard_regno_profit1 = 0;
1389 lra_reg_info[i].preferred_hard_regno_profit2 = 0;
1390 lra_reg_info[i].live_ranges = NULL;
1391 lra_reg_info[i].nrefs = lra_reg_info[i].freq = 0;
1392 lra_reg_info[i].last_reload = 0;
1393 lra_reg_info[i].restore_regno = -1;
1394 lra_reg_info[i].val = get_new_reg_value ();
1395 lra_reg_info[i].copies = NULL;
1396 }
1397
1398 /* Initialize common reg info and copies. */
1399 static void
1400 init_reg_info (void)
1401 {
1402 int i;
1403
1404 last_reg_value = 0;
1405 reg_info_size = max_reg_num () * 3 / 2 + 1;
1406 lra_reg_info = XNEWVEC (struct lra_reg, reg_info_size);
1407 for (i = 0; i < reg_info_size; i++)
1408 initialize_lra_reg_info_element (i);
1409 copy_pool
1410 = create_alloc_pool ("lra copies", sizeof (struct lra_copy), 100);
1411 copy_vec = VEC_alloc (lra_copy_t, heap, 100);
1412 }
1413
1414
1415 /* Finish common reg info and copies. */
1416 static void
1417 finish_reg_info (void)
1418 {
1419 int i;
1420
1421 for (i = 0; i < reg_info_size; i++)
1422 bitmap_clear (&lra_reg_info[i].insn_bitmap);
1423 free (lra_reg_info);
1424 reg_info_size = 0;
1425 free_alloc_pool (copy_pool);
1426 VEC_free (lra_copy_t, heap, copy_vec);
1427 }
1428
1429 /* Expand common reg info if it is necessary. */
1430 static void
1431 expand_reg_info (void)
1432 {
1433 int i, old = reg_info_size;
1434
1435 if (reg_info_size > max_reg_num ())
1436 return;
1437 reg_info_size = max_reg_num () * 3 / 2 + 1;
1438 lra_reg_info = XRESIZEVEC (struct lra_reg, lra_reg_info, reg_info_size);
1439 for (i = old; i < reg_info_size; i++)
1440 initialize_lra_reg_info_element (i);
1441 }
1442
1443 /* Free all copies. */
1444 void
1445 lra_free_copies (void)
1446 {
1447 lra_copy_t cp;
1448
1449 while (VEC_length (lra_copy_t, copy_vec) != 0)
1450 {
1451 cp = VEC_pop (lra_copy_t, copy_vec);
1452 lra_reg_info[cp->regno1].copies = lra_reg_info[cp->regno2].copies = NULL;
1453 pool_free (copy_pool, cp);
1454 }
1455 }
1456
1457 /* Create copy of two pseudos REGNO1 and REGNO2. The copy execution
1458 frequency is FREQ. */
1459 void
1460 lra_create_copy (int regno1, int regno2, int freq)
1461 {
1462 bool regno1_dest_p;
1463 lra_copy_t cp;
1464
1465 lra_assert (regno1 != regno2);
1466 regno1_dest_p = true;
1467 if (regno1 > regno2)
1468 {
1469 int temp = regno2;
1470
1471 regno1_dest_p = false;
1472 regno2 = regno1;
1473 regno1 = temp;
1474 }
1475 cp = (lra_copy_t) pool_alloc (copy_pool);
1476 VEC_safe_push (lra_copy_t, heap, copy_vec, cp);
1477 cp->regno1_dest_p = regno1_dest_p;
1478 cp->freq = freq;
1479 cp->regno1 = regno1;
1480 cp->regno2 = regno2;
1481 cp->regno1_next = lra_reg_info[regno1].copies;
1482 lra_reg_info[regno1].copies = cp;
1483 cp->regno2_next = lra_reg_info[regno2].copies;
1484 lra_reg_info[regno2].copies = cp;
1485 if (lra_dump_file != NULL)
1486 fprintf (lra_dump_file, " Creating copy r%d%sr%d@%d\n",
1487 regno1, regno1_dest_p ? "<-" : "->", regno2, freq);
1488 }
1489
1490 /* Return N-th (0, 1, ...) copy. If there is no copy, return
1491 NULL. */
1492 lra_copy_t
1493 lra_get_copy (int n)
1494 {
1495 if (n >= (int) VEC_length (lra_copy_t, copy_vec))
1496 return NULL;
1497 return VEC_index (lra_copy_t, copy_vec, n);
1498 }
1499
1500 \f
1501
1502 /* This page contains code dealing with info about registers in
1503 insns. */
1504
1505 /* Process X of insn UID recursively and add info (operand type is
1506 given by TYPE, flag of that it is early clobber is EARLY_CLOBBER)
1507 about registers in X to the insn DATA. */
1508 static void
1509 add_regs_to_insn_regno_info (lra_insn_recog_data_t data, rtx x, int uid,
1510 enum op_type type, bool early_clobber)
1511 {
1512 int i, j, regno;
1513 bool subreg_p;
1514 enum machine_mode mode;
1515 const char *fmt;
1516 enum rtx_code code;
1517 struct lra_insn_reg *curr;
1518
1519 code = GET_CODE (x);
1520 mode = GET_MODE (x);
1521 subreg_p = false;
1522 if (GET_CODE (x) == SUBREG)
1523 {
1524 x = SUBREG_REG (x);
1525 code = GET_CODE (x);
1526 if (GET_MODE_SIZE (mode) < GET_MODE_SIZE (GET_MODE (x)))
1527 {
1528 mode = GET_MODE (x);
1529 if (GET_MODE_SIZE (mode) > REGMODE_NATURAL_SIZE (mode))
1530 subreg_p = true;
1531 }
1532 }
1533 if (REG_P (x))
1534 {
1535 regno = REGNO (x);
1536 expand_reg_info ();
1537 if (bitmap_set_bit (&lra_reg_info[regno].insn_bitmap, uid))
1538 {
1539 data->regs = new_insn_reg (regno, type, mode, subreg_p,
1540 early_clobber, data->regs);
1541 return;
1542 }
1543 else
1544 {
1545 for (curr = data->regs; curr != NULL; curr = curr->next)
1546 if (curr->regno == regno)
1547 {
1548 if (curr->subreg_p != subreg_p || curr->biggest_mode != mode)
1549 /* The info can not be integrated into the found
1550 structure. */
1551 data->regs = new_insn_reg (regno, type, mode, subreg_p,
1552 early_clobber, data->regs);
1553 else
1554 {
1555 if (curr->type != type)
1556 curr->type = OP_INOUT;
1557 if (curr->early_clobber != early_clobber)
1558 curr->early_clobber = true;
1559 }
1560 return;
1561 }
1562 gcc_unreachable ();
1563 }
1564 }
1565
1566 switch (code)
1567 {
1568 case SET:
1569 add_regs_to_insn_regno_info (data, SET_DEST (x), uid, OP_OUT, false);
1570 add_regs_to_insn_regno_info (data, SET_SRC (x), uid, OP_IN, false);
1571 break;
1572 case CLOBBER:
1573 /* We treat clobber of non-operand hard registers as early
1574 clobber (the behavior is expected from asm). */
1575 add_regs_to_insn_regno_info (data, XEXP (x, 0), uid, OP_OUT, true);
1576 break;
1577 case PRE_INC: case PRE_DEC: case POST_INC: case POST_DEC:
1578 add_regs_to_insn_regno_info (data, XEXP (x, 0), uid, OP_INOUT, false);
1579 break;
1580 case PRE_MODIFY: case POST_MODIFY:
1581 add_regs_to_insn_regno_info (data, XEXP (x, 0), uid, OP_INOUT, false);
1582 add_regs_to_insn_regno_info (data, XEXP (x, 1), uid, OP_IN, false);
1583 break;
1584 default:
1585 if ((code != PARALLEL && code != EXPR_LIST) || type != OP_OUT)
1586 /* Some targets place small structures in registers for return
1587 values of functions, and those registers are wrapped in
1588 PARALLEL that we may see as the destination of a SET. Here
1589 is an example:
1590
1591 (call_insn 13 12 14 2 (set (parallel:BLK [
1592 (expr_list:REG_DEP_TRUE (reg:DI 0 ax)
1593 (const_int 0 [0]))
1594 (expr_list:REG_DEP_TRUE (reg:DI 1 dx)
1595 (const_int 8 [0x8]))
1596 ])
1597 (call (mem:QI (symbol_ref:DI (... */
1598 type = OP_IN;
1599 fmt = GET_RTX_FORMAT (code);
1600 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1601 {
1602 if (fmt[i] == 'e')
1603 add_regs_to_insn_regno_info (data, XEXP (x, i), uid, type, false);
1604 else if (fmt[i] == 'E')
1605 {
1606 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
1607 add_regs_to_insn_regno_info (data, XVECEXP (x, i, j), uid,
1608 type, false);
1609 }
1610 }
1611 }
1612 }
1613
1614 /* Return execution frequency of INSN. */
1615 static int
1616 get_insn_freq (rtx insn)
1617 {
1618 basic_block bb;
1619
1620 if ((bb = BLOCK_FOR_INSN (insn)) != NULL)
1621 return REG_FREQ_FROM_BB (bb);
1622 else
1623 {
1624 lra_assert (lra_insn_recog_data[INSN_UID (insn)]
1625 ->insn_static_data->n_operands == 0);
1626 /* We don't care about such insn, e.g. it might be jump with
1627 addr_vec. */
1628 return 1;
1629 }
1630 }
1631
1632 /* Invalidate all reg info of INSN with DATA and execution frequency
1633 FREQ. Update common info about the invalidated registers. */
1634 static void
1635 invalidate_insn_data_regno_info (lra_insn_recog_data_t data, rtx insn,
1636 int freq)
1637 {
1638 int uid;
1639 bool debug_p;
1640 unsigned int i;
1641 struct lra_insn_reg *ir, *next_ir;
1642
1643 uid = INSN_UID (insn);
1644 debug_p = DEBUG_INSN_P (insn);
1645 for (ir = data->regs; ir != NULL; ir = next_ir)
1646 {
1647 i = ir->regno;
1648 next_ir = ir->next;
1649 free_insn_reg (ir);
1650 bitmap_clear_bit (&lra_reg_info[i].insn_bitmap, uid);
1651 if (i >= FIRST_PSEUDO_REGISTER && ! debug_p)
1652 {
1653 lra_reg_info[i].nrefs--;
1654 lra_reg_info[i].freq -= freq;
1655 lra_assert (lra_reg_info[i].nrefs >= 0 && lra_reg_info[i].freq >= 0);
1656 }
1657 }
1658 data->regs = NULL;
1659 }
1660
1661 /* Invalidate all reg info of INSN. Update common info about the
1662 invalidated registers. */
1663 void
1664 lra_invalidate_insn_regno_info (rtx insn)
1665 {
1666 invalidate_insn_data_regno_info (lra_get_insn_recog_data (insn), insn,
1667 get_insn_freq (insn));
1668 }
1669
1670 /* Update common reg info from reg info of insn given by its DATA and
1671 execution frequency FREQ. */
1672 static void
1673 setup_insn_reg_info (lra_insn_recog_data_t data, int freq)
1674 {
1675 unsigned int i;
1676 struct lra_insn_reg *ir;
1677
1678 for (ir = data->regs; ir != NULL; ir = ir->next)
1679 if ((i = ir->regno) >= FIRST_PSEUDO_REGISTER)
1680 {
1681 lra_reg_info[i].nrefs++;
1682 lra_reg_info[i].freq += freq;
1683 }
1684 }
1685
1686 /* Set up insn reg info of INSN. Update common reg info from reg info
1687 of INSN. */
1688 void
1689 lra_update_insn_regno_info (rtx insn)
1690 {
1691 int i, uid, freq;
1692 lra_insn_recog_data_t data;
1693 struct lra_static_insn_data *static_data;
1694 enum rtx_code code;
1695
1696 if (! INSN_P (insn))
1697 return;
1698 data = lra_get_insn_recog_data (insn);
1699 static_data = data->insn_static_data;
1700 freq = get_insn_freq (insn);
1701 invalidate_insn_data_regno_info (data, insn, freq);
1702 uid = INSN_UID (insn);
1703 for (i = static_data->n_operands - 1; i >= 0; i--)
1704 add_regs_to_insn_regno_info (data, *data->operand_loc[i], uid,
1705 static_data->operand[i].type,
1706 static_data->operand[i].early_clobber);
1707 if ((code = GET_CODE (PATTERN (insn))) == CLOBBER || code == USE)
1708 add_regs_to_insn_regno_info (data, XEXP (PATTERN (insn), 0), uid,
1709 code == USE ? OP_IN : OP_OUT, false);
1710 if (NONDEBUG_INSN_P (insn))
1711 setup_insn_reg_info (data, freq);
1712 }
1713
1714 /* Return reg info of insn given by it UID. */
1715 struct lra_insn_reg *
1716 lra_get_insn_regs (int uid)
1717 {
1718 lra_insn_recog_data_t data;
1719
1720 data = get_insn_recog_data_by_uid (uid);
1721 return data->regs;
1722 }
1723
1724 \f
1725
1726 /* This page contains code dealing with stack of the insns which
1727 should be processed by the next constraint pass. */
1728
1729 /* Bitmap used to put an insn on the stack only in one exemplar. */
1730 static sbitmap lra_constraint_insn_stack_bitmap;
1731
1732 /* The stack itself. */
1733 VEC (rtx, heap) *lra_constraint_insn_stack;
1734
1735 /* Put INSN on the stack. If ALWAYS_UPDATE is true, always update the reg
1736 info for INSN, otherwise only update it if INSN is not already on the
1737 stack. */
1738 static inline void
1739 lra_push_insn_1 (rtx insn, bool always_update)
1740 {
1741 unsigned int uid = INSN_UID (insn);
1742 if (always_update)
1743 lra_update_insn_regno_info (insn);
1744 if (uid >= SBITMAP_SIZE (lra_constraint_insn_stack_bitmap))
1745 lra_constraint_insn_stack_bitmap =
1746 sbitmap_resize (lra_constraint_insn_stack_bitmap, 3 * uid / 2, 0);
1747 if (bitmap_bit_p (lra_constraint_insn_stack_bitmap, uid))
1748 return;
1749 bitmap_set_bit (lra_constraint_insn_stack_bitmap, uid);
1750 if (! always_update)
1751 lra_update_insn_regno_info (insn);
1752 VEC_safe_push (rtx, heap, lra_constraint_insn_stack, insn);
1753 }
1754
1755 /* Put INSN on the stack. */
1756 void
1757 lra_push_insn (rtx insn)
1758 {
1759 lra_push_insn_1 (insn, false);
1760 }
1761
1762 /* Put INSN on the stack and update its reg info. */
1763 void
1764 lra_push_insn_and_update_insn_regno_info (rtx insn)
1765 {
1766 lra_push_insn_1 (insn, true);
1767 }
1768
1769 /* Put insn with UID on the stack. */
1770 void
1771 lra_push_insn_by_uid (unsigned int uid)
1772 {
1773 lra_push_insn (lra_insn_recog_data[uid]->insn);
1774 }
1775
1776 /* Take the last-inserted insns off the stack and return it. */
1777 rtx
1778 lra_pop_insn (void)
1779 {
1780 rtx insn = VEC_pop (rtx, lra_constraint_insn_stack);
1781 bitmap_clear_bit (lra_constraint_insn_stack_bitmap, INSN_UID (insn));
1782 return insn;
1783 }
1784
1785 /* Return the current size of the insn stack. */
1786 unsigned int
1787 lra_insn_stack_length (void)
1788 {
1789 return VEC_length (rtx, lra_constraint_insn_stack);
1790 }
1791
1792 /* Push insns FROM to TO (excluding it) going in reverse order. */
1793 static void
1794 push_insns (rtx from, rtx to)
1795 {
1796 rtx insn;
1797
1798 if (from == NULL_RTX)
1799 return;
1800 for (insn = from; insn != to; insn = PREV_INSN (insn))
1801 if (INSN_P (insn))
1802 lra_push_insn (insn);
1803 }
1804
1805 /* Emit insns BEFORE before INSN and insns AFTER after INSN. Put the
1806 insns onto the stack. Print about emitting the insns with
1807 TITLE. */
1808 void
1809 lra_process_new_insns (rtx insn, rtx before, rtx after, const char *title)
1810 {
1811 rtx last;
1812
1813 if (lra_dump_file != NULL && (before != NULL_RTX || after != NULL_RTX))
1814 {
1815 debug_rtl_slim (lra_dump_file, insn, insn, -1, 0);
1816 if (before != NULL_RTX)
1817 {
1818 fprintf (lra_dump_file," %s before:\n", title);
1819 debug_rtl_slim (lra_dump_file, before, NULL_RTX, -1, 0);
1820 }
1821 if (after != NULL_RTX)
1822 {
1823 fprintf (lra_dump_file, " %s after:\n", title);
1824 debug_rtl_slim (lra_dump_file, after, NULL_RTX, -1, 0);
1825 }
1826 fprintf (lra_dump_file, "\n");
1827 }
1828 if (before != NULL_RTX)
1829 {
1830 emit_insn_before (before, insn);
1831 push_insns (PREV_INSN (insn), PREV_INSN (before));
1832 }
1833 if (after != NULL_RTX)
1834 {
1835 for (last = after; NEXT_INSN (last) != NULL_RTX; last = NEXT_INSN (last))
1836 ;
1837 emit_insn_after (after, insn);
1838 push_insns (last, insn);
1839 }
1840 }
1841
1842 \f
1843
1844 /* This page contains code dealing with scratches (changing them onto
1845 pseudos and restoring them from the pseudos).
1846
1847 We change scratches into pseudos at the beginning of LRA to
1848 simplify dealing with them (conflicts, hard register assignments).
1849
1850 If the pseudo denoting scratch was spilled it means that we do need
1851 a hard register for it. Such pseudos are transformed back to
1852 scratches at the end of LRA. */
1853
1854 /* Description of location of a former scratch operand. */
1855 struct sloc
1856 {
1857 rtx insn; /* Insn where the scratch was. */
1858 int nop; /* Number of the operand which was a scratch. */
1859 };
1860
1861 typedef struct sloc *sloc_t;
1862
1863 DEF_VEC_P(sloc_t);
1864 DEF_VEC_ALLOC_P(sloc_t, heap);
1865
1866 /* Locations of the former scratches. */
1867 static VEC (sloc_t, heap) *scratches;
1868
1869 /* Bitmap of scratch regnos. */
1870 static bitmap_head scratch_bitmap;
1871
1872 /* Bitmap of scratch operands. */
1873 static bitmap_head scratch_operand_bitmap;
1874
1875 /* Return true if pseudo REGNO is made of SCRATCH. */
1876 bool
1877 lra_former_scratch_p (int regno)
1878 {
1879 return bitmap_bit_p (&scratch_bitmap, regno);
1880 }
1881
1882 /* Return true if the operand NOP of INSN is a former scratch. */
1883 bool
1884 lra_former_scratch_operand_p (rtx insn, int nop)
1885 {
1886 return bitmap_bit_p (&scratch_operand_bitmap,
1887 INSN_UID (insn) * MAX_RECOG_OPERANDS + nop) != 0;
1888 }
1889
1890 /* Change scratches onto pseudos and save their location. */
1891 static void
1892 remove_scratches (void)
1893 {
1894 int i;
1895 bool insn_changed_p;
1896 basic_block bb;
1897 rtx insn, reg;
1898 sloc_t loc;
1899 lra_insn_recog_data_t id;
1900 struct lra_static_insn_data *static_id;
1901
1902 scratches = VEC_alloc (sloc_t, heap, get_max_uid ());
1903 bitmap_initialize (&scratch_bitmap, &reg_obstack);
1904 bitmap_initialize (&scratch_operand_bitmap, &reg_obstack);
1905 FOR_EACH_BB (bb)
1906 FOR_BB_INSNS (bb, insn)
1907 if (INSN_P (insn))
1908 {
1909 id = lra_get_insn_recog_data (insn);
1910 static_id = id->insn_static_data;
1911 insn_changed_p = false;
1912 for (i = 0; i < static_id->n_operands; i++)
1913 if (GET_CODE (*id->operand_loc[i]) == SCRATCH
1914 && GET_MODE (*id->operand_loc[i]) != VOIDmode)
1915 {
1916 insn_changed_p = true;
1917 *id->operand_loc[i] = reg
1918 = lra_create_new_reg (static_id->operand[i].mode,
1919 *id->operand_loc[i], ALL_REGS, NULL);
1920 add_reg_note (insn, REG_UNUSED, reg);
1921 lra_update_dup (id, i);
1922 loc = XNEW (struct sloc);
1923 loc->insn = insn;
1924 loc->nop = i;
1925 VEC_safe_push (sloc_t, heap, scratches, loc);
1926 bitmap_set_bit (&scratch_bitmap, REGNO (*id->operand_loc[i]));
1927 bitmap_set_bit (&scratch_operand_bitmap,
1928 INSN_UID (insn) * MAX_RECOG_OPERANDS + i);
1929 if (lra_dump_file != NULL)
1930 fprintf (lra_dump_file,
1931 "Removing SCRATCH in insn #%u (nop %d)\n",
1932 INSN_UID (insn), i);
1933 }
1934 if (insn_changed_p)
1935 /* Because we might use DF right after caller-saves sub-pass
1936 we need to keep DF info up to date. */
1937 df_insn_rescan (insn);
1938 }
1939 }
1940
1941 /* Changes pseudos created by function remove_scratches onto scratches. */
1942 static void
1943 restore_scratches (void)
1944 {
1945 int i, regno;
1946 sloc_t loc;
1947 rtx last = NULL_RTX;
1948 lra_insn_recog_data_t id = NULL;
1949
1950 for (i = 0; VEC_iterate (sloc_t, scratches, i, loc); i++)
1951 {
1952 if (last != loc->insn)
1953 {
1954 last = loc->insn;
1955 id = lra_get_insn_recog_data (last);
1956 }
1957 if (REG_P (*id->operand_loc[loc->nop])
1958 && ((regno = REGNO (*id->operand_loc[loc->nop]))
1959 >= FIRST_PSEUDO_REGISTER)
1960 && lra_get_regno_hard_regno (regno) < 0)
1961 {
1962 /* It should be only case when scratch register with chosen
1963 constraint 'X' did not get memory or hard register. */
1964 lra_assert (lra_former_scratch_p (regno));
1965 *id->operand_loc[loc->nop]
1966 = gen_rtx_SCRATCH (GET_MODE (*id->operand_loc[loc->nop]));
1967 lra_update_dup (id, loc->nop);
1968 if (lra_dump_file != NULL)
1969 fprintf (lra_dump_file, "Restoring SCRATCH in insn #%u(nop %d)\n",
1970 INSN_UID (loc->insn), loc->nop);
1971 }
1972 }
1973 for (i = 0; VEC_iterate (sloc_t, scratches, i, loc); i++)
1974 free (loc);
1975 VEC_free (sloc_t, heap, scratches);
1976 bitmap_clear (&scratch_bitmap);
1977 bitmap_clear (&scratch_operand_bitmap);
1978 }
1979
1980 \f
1981
1982 #ifdef ENABLE_CHECKING
1983
1984 /* Function checks RTL for correctness. If FINAL_P is true, it is
1985 done at the end of LRA and the check is more rigorous. */
1986 static void
1987 check_rtl (bool final_p)
1988 {
1989 int i;
1990 basic_block bb;
1991 rtx insn;
1992 lra_insn_recog_data_t id;
1993
1994 lra_assert (! final_p || reload_completed);
1995 FOR_EACH_BB (bb)
1996 FOR_BB_INSNS (bb, insn)
1997 if (NONDEBUG_INSN_P (insn)
1998 && GET_CODE (PATTERN (insn)) != USE
1999 && GET_CODE (PATTERN (insn)) != CLOBBER
2000 && GET_CODE (PATTERN (insn)) != ADDR_VEC
2001 && GET_CODE (PATTERN (insn)) != ADDR_DIFF_VEC
2002 && GET_CODE (PATTERN (insn)) != ASM_INPUT)
2003 {
2004 if (final_p)
2005 {
2006 extract_insn (insn);
2007 lra_assert (constrain_operands (1));
2008 continue;
2009 }
2010 if (insn_invalid_p (insn, false))
2011 fatal_insn_not_found (insn);
2012 if (asm_noperands (PATTERN (insn)) >= 0)
2013 continue;
2014 id = lra_get_insn_recog_data (insn);
2015 /* The code is based on assumption that all addresses in
2016 regular instruction are legitimate before LRA. The code in
2017 lra-constraints.c is based on assumption that there is no
2018 subreg of memory as an insn operand. */
2019 for (i = 0; i < id->insn_static_data->n_operands; i++)
2020 {
2021 rtx op = *id->operand_loc[i];
2022
2023 if (MEM_P (op)
2024 && (GET_MODE (op) != BLKmode
2025 || GET_CODE (XEXP (op, 0)) != SCRATCH)
2026 && ! memory_address_p (GET_MODE (op), XEXP (op, 0))
2027 /* Some ports don't recognize the following addresses
2028 as legitimate. Although they are legitimate if
2029 they satisfies the constraints and will be checked
2030 by insn constraints which we ignore here. */
2031 && GET_CODE (XEXP (op, 0)) != UNSPEC
2032 && GET_RTX_CLASS (GET_CODE (XEXP (op, 0))) != RTX_AUTOINC)
2033 fatal_insn_not_found (insn);
2034 }
2035 }
2036 }
2037 #endif /* #ifdef ENABLE_CHECKING */
2038
2039 /* Determine if the current function has an exception receiver block
2040 that reaches the exit block via non-exceptional edges */
2041 static bool
2042 has_nonexceptional_receiver (void)
2043 {
2044 edge e;
2045 edge_iterator ei;
2046 basic_block *tos, *worklist, bb;
2047
2048 /* If we're not optimizing, then just err on the safe side. */
2049 if (!optimize)
2050 return true;
2051
2052 /* First determine which blocks can reach exit via normal paths. */
2053 tos = worklist = XNEWVEC (basic_block, n_basic_blocks + 1);
2054
2055 FOR_EACH_BB (bb)
2056 bb->flags &= ~BB_REACHABLE;
2057
2058 /* Place the exit block on our worklist. */
2059 EXIT_BLOCK_PTR->flags |= BB_REACHABLE;
2060 *tos++ = EXIT_BLOCK_PTR;
2061
2062 /* Iterate: find everything reachable from what we've already seen. */
2063 while (tos != worklist)
2064 {
2065 bb = *--tos;
2066
2067 FOR_EACH_EDGE (e, ei, bb->preds)
2068 if (e->flags & EDGE_ABNORMAL)
2069 {
2070 free (worklist);
2071 return true;
2072 }
2073 else
2074 {
2075 basic_block src = e->src;
2076
2077 if (!(src->flags & BB_REACHABLE))
2078 {
2079 src->flags |= BB_REACHABLE;
2080 *tos++ = src;
2081 }
2082 }
2083 }
2084 free (worklist);
2085 /* No exceptional block reached exit unexceptionally. */
2086 return false;
2087 }
2088
2089 #ifdef AUTO_INC_DEC
2090
2091 /* Process recursively X of INSN and add REG_INC notes if necessary. */
2092 static void
2093 add_auto_inc_notes (rtx insn, rtx x)
2094 {
2095 enum rtx_code code = GET_CODE (x);
2096 const char *fmt;
2097 int i, j;
2098
2099 if (code == MEM && auto_inc_p (XEXP (x, 0)))
2100 {
2101 add_reg_note (insn, REG_INC, XEXP (XEXP (x, 0), 0));
2102 return;
2103 }
2104
2105 /* Scan all X sub-expressions. */
2106 fmt = GET_RTX_FORMAT (code);
2107 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
2108 {
2109 if (fmt[i] == 'e')
2110 add_auto_inc_notes (insn, XEXP (x, i));
2111 else if (fmt[i] == 'E')
2112 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
2113 add_auto_inc_notes (insn, XVECEXP (x, i, j));
2114 }
2115 }
2116
2117 #endif
2118
2119 /* Remove all REG_DEAD and REG_UNUSED notes and regenerate REG_INC.
2120 We change pseudos by hard registers without notification of DF and
2121 that can make the notes obsolete. DF-infrastructure does not deal
2122 with REG_INC notes -- so we should regenerate them here. */
2123 static void
2124 update_inc_notes (void)
2125 {
2126 rtx *pnote;
2127 basic_block bb;
2128 rtx insn;
2129
2130 FOR_EACH_BB (bb)
2131 FOR_BB_INSNS (bb, insn)
2132 if (NONDEBUG_INSN_P (insn))
2133 {
2134 pnote = &REG_NOTES (insn);
2135 while (*pnote != 0)
2136 {
2137 if (REG_NOTE_KIND (*pnote) == REG_INC)
2138 *pnote = XEXP (*pnote, 1);
2139 else
2140 pnote = &XEXP (*pnote, 1);
2141 }
2142 #ifdef AUTO_INC_DEC
2143 add_auto_inc_notes (insn, PATTERN (insn));
2144 #endif
2145 }
2146 }
2147
2148 /* Set to 1 while in lra. */
2149 int lra_in_progress;
2150
2151 /* Start of reload pseudo regnos before the new spill pass. */
2152 int lra_constraint_new_regno_start;
2153
2154 /* Inheritance pseudo regnos before the new spill pass. */
2155 bitmap_head lra_inheritance_pseudos;
2156
2157 /* Split regnos before the new spill pass. */
2158 bitmap_head lra_split_regs;
2159
2160 /* Reload pseudo regnos before the new assign pass which still can be
2161 spilled after the assinment pass. */
2162 bitmap_head lra_optional_reload_pseudos;
2163
2164 /* First UID of insns generated before a new spill pass. */
2165 int lra_constraint_new_insn_uid_start;
2166
2167 /* File used for output of LRA debug information. */
2168 FILE *lra_dump_file;
2169
2170 /* True if we should try spill into registers of different classes
2171 instead of memory. */
2172 bool lra_reg_spill_p;
2173
2174 /* Set up value LRA_REG_SPILL_P. */
2175 static void
2176 setup_reg_spill_flag (void)
2177 {
2178 int cl, mode;
2179
2180 if (targetm.spill_class != NULL)
2181 for (cl = 0; cl < (int) LIM_REG_CLASSES; cl++)
2182 for (mode = 0; mode < MAX_MACHINE_MODE; mode++)
2183 if (targetm.spill_class ((enum reg_class) cl,
2184 (enum machine_mode) mode) != NO_REGS)
2185 {
2186 lra_reg_spill_p = true;
2187 return;
2188 }
2189 lra_reg_spill_p = false;
2190 }
2191
2192 /* True if the current function is too big to use regular algorithms
2193 in LRA. In other words, we should use simpler and faster algorithms
2194 in LRA. It also means we should not worry about generation code
2195 for caller saves. The value is set up in IRA. */
2196 bool lra_simple_p;
2197
2198 /* Major LRA entry function. F is a file should be used to dump LRA
2199 debug info. */
2200 void
2201 lra (FILE *f)
2202 {
2203 int i;
2204 bool live_p, scratch_p, inserted_p;
2205
2206 lra_dump_file = f;
2207
2208 timevar_push (TV_LRA);
2209
2210 init_insn_recog_data ();
2211
2212 #ifdef ENABLE_CHECKING
2213 check_rtl (false);
2214 #endif
2215
2216 COPY_HARD_REG_SET (lra_no_alloc_regs, ira_no_alloc_regs);
2217
2218 lra_live_range_iter = lra_coalesce_iter = 0;
2219 lra_constraint_iter = lra_constraint_iter_after_spill = 0;
2220 lra_inheritance_iter = lra_undo_inheritance_iter = 0;
2221
2222 setup_reg_spill_flag ();
2223
2224 /* We can not set up reload_in_progress because it prevents new
2225 pseudo creation. */
2226 lra_in_progress = 1;
2227
2228 init_reg_info ();
2229 expand_reg_info ();
2230
2231 /* Function remove_scratches can creates new pseudos for clobbers --
2232 so set up lra_constraint_new_regno_start before its call to
2233 permit changing reg classes for pseudos created by this
2234 simplification. */
2235 lra_constraint_new_regno_start = max_reg_num ();
2236 remove_scratches ();
2237 scratch_p = lra_constraint_new_regno_start != max_reg_num ();
2238
2239 /* A function that has a non-local label that can reach the exit
2240 block via non-exceptional paths must save all call-saved
2241 registers. */
2242 if (cfun->has_nonlocal_label && has_nonexceptional_receiver ())
2243 crtl->saves_all_registers = 1;
2244
2245 if (crtl->saves_all_registers)
2246 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
2247 if (! call_used_regs[i] && ! fixed_regs[i] && ! LOCAL_REGNO (i))
2248 df_set_regs_ever_live (i, true);
2249
2250 /* We don't DF from now and avoid its using because it is to
2251 expensive when a lot of RTL changes are made. */
2252 df_set_flags (DF_NO_INSN_RESCAN);
2253 lra_constraint_insn_stack = VEC_alloc (rtx, heap, get_max_uid ());
2254 lra_constraint_insn_stack_bitmap = sbitmap_alloc (get_max_uid ());
2255 bitmap_clear (lra_constraint_insn_stack_bitmap);
2256 lra_live_ranges_init ();
2257 lra_constraints_init ();
2258 lra_curr_reload_num = 0;
2259 push_insns (get_last_insn (), NULL_RTX);
2260 /* It is needed for the 1st coalescing. */
2261 lra_constraint_new_insn_uid_start = get_max_uid ();
2262 bitmap_initialize (&lra_inheritance_pseudos, &reg_obstack);
2263 bitmap_initialize (&lra_split_regs, &reg_obstack);
2264 bitmap_initialize (&lra_optional_reload_pseudos, &reg_obstack);
2265 live_p = false;
2266 for (;;)
2267 {
2268 for (;;)
2269 {
2270 bitmap_clear (&lra_optional_reload_pseudos);
2271 /* We should try to assign hard registers to scratches even
2272 if there were no RTL transformations in
2273 lra_constraints. */
2274 if (! lra_constraints (lra_constraint_iter == 0)
2275 && (lra_constraint_iter > 1
2276 || (! scratch_p && ! caller_save_needed)))
2277 break;
2278 /* Constraint transformations may result in that eliminable
2279 hard regs become uneliminable and pseudos which use them
2280 should be spilled. It is better to do it before pseudo
2281 assignments.
2282
2283 For example, rs6000 can make
2284 RS6000_PIC_OFFSET_TABLE_REGNUM uneliminable if we started
2285 to use a constant pool. */
2286 lra_eliminate (false);
2287 /* Do inheritance only for regular algorithms. */
2288 if (! lra_simple_p)
2289 lra_inheritance ();
2290 /* We need live ranges for lra_assign -- so build them. */
2291 lra_create_live_ranges (true);
2292 live_p = true;
2293 /* If we don't spill non-reload and non-inheritance pseudos,
2294 there is no sense to run memory-memory move coalescing.
2295 If inheritance pseudos were spilled, the memory-memory
2296 moves involving them will be removed by pass undoing
2297 inheritance. */
2298 if (lra_simple_p)
2299 lra_assign ();
2300 else
2301 {
2302 /* Do coalescing only for regular algorithms. */
2303 if (! lra_assign () && lra_coalesce ())
2304 live_p = false;
2305 if (lra_undo_inheritance ())
2306 live_p = false;
2307 }
2308 }
2309 bitmap_clear (&lra_inheritance_pseudos);
2310 bitmap_clear (&lra_split_regs);
2311 if (! lra_need_for_spills_p ())
2312 break;
2313 if (! live_p)
2314 {
2315 /* We need full live info for spilling pseudos into
2316 registers instead of memory. */
2317 lra_create_live_ranges (lra_reg_spill_p);
2318 live_p = true;
2319 }
2320 lra_spill ();
2321 /* Assignment of stack slots changes elimination offsets for
2322 some eliminations. So update the offsets here. */
2323 lra_eliminate (false);
2324 lra_constraint_new_regno_start = max_reg_num ();
2325 lra_constraint_new_insn_uid_start = get_max_uid ();
2326 lra_constraint_iter_after_spill = 0;
2327 }
2328 restore_scratches ();
2329 lra_eliminate (true);
2330 lra_final_code_change ();
2331 lra_in_progress = 0;
2332 lra_clear_live_ranges ();
2333 lra_live_ranges_finish ();
2334 lra_constraints_finish ();
2335 finish_reg_info ();
2336 sbitmap_free (lra_constraint_insn_stack_bitmap);
2337 VEC_free (rtx, heap, lra_constraint_insn_stack);
2338 finish_insn_recog_data ();
2339 regstat_free_n_sets_and_refs ();
2340 regstat_free_ri ();
2341 reload_completed = 1;
2342 update_inc_notes ();
2343
2344 inserted_p = fixup_abnormal_edges ();
2345
2346 /* We've possibly turned single trapping insn into multiple ones. */
2347 if (cfun->can_throw_non_call_exceptions)
2348 {
2349 sbitmap blocks;
2350 blocks = sbitmap_alloc (last_basic_block);
2351 bitmap_ones (blocks);
2352 find_many_sub_basic_blocks (blocks);
2353 sbitmap_free (blocks);
2354 }
2355
2356 if (inserted_p)
2357 commit_edge_insertions ();
2358
2359 /* Replacing pseudos with their memory equivalents might have
2360 created shared rtx. Subsequent passes would get confused
2361 by this, so unshare everything here. */
2362 unshare_all_rtl_again (get_insns ());
2363
2364 #ifdef ENABLE_CHECKING
2365 check_rtl (true);
2366 #endif
2367
2368 timevar_pop (TV_LRA);
2369 }
2370
2371 /* Called once per compiler to initialize LRA data once. */
2372 void
2373 lra_init_once (void)
2374 {
2375 init_insn_code_data_once ();
2376 }
2377
2378 /* Initialize LRA whenever register-related information is changed. */
2379 void
2380 lra_init (void)
2381 {
2382 init_op_alt_data ();
2383 }
2384
2385 /* Called once per compiler to finish LRA data which are initialize
2386 once. */
2387 void
2388 lra_finish_once (void)
2389 {
2390 finish_insn_code_data_once ();
2391 }