libstdc++: Make views::single/iota/istream SFINAE-friendly [PR108362]
[official-gcc.git] / gcc / ira-costs.cc
blobc0fdef807dd6112a00829cb4fb97c51644a3fa5a
1 /* IRA hard register and memory cost calculation for allocnos or pseudos.
2 Copyright (C) 2006-2023 Free Software Foundation, Inc.
3 Contributed by Vladimir Makarov <vmakarov@redhat.com>.
5 This file is part of GCC.
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.
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.
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/>. */
21 #include "config.h"
22 #include "system.h"
23 #include "coretypes.h"
24 #include "backend.h"
25 #include "target.h"
26 #include "rtl.h"
27 #include "tree.h"
28 #include "predict.h"
29 #include "memmodel.h"
30 #include "tm_p.h"
31 #include "insn-config.h"
32 #include "regs.h"
33 #include "ira.h"
34 #include "ira-int.h"
35 #include "addresses.h"
36 #include "reload.h"
37 #include "print-rtl.h"
39 /* The flags is set up every time when we calculate pseudo register
40 classes through function ira_set_pseudo_classes. */
41 static bool pseudo_classes_defined_p = false;
43 /* TRUE if we work with allocnos. Otherwise we work with pseudos. */
44 static bool allocno_p;
46 /* Number of elements in array `costs'. */
47 static int cost_elements_num;
49 /* The `costs' struct records the cost of using hard registers of each
50 class considered for the calculation and of using memory for each
51 allocno or pseudo. */
52 struct costs
54 int mem_cost;
55 /* Costs for register classes start here. We process only some
56 allocno classes. */
57 int cost[1];
60 #define max_struct_costs_size \
61 (this_target_ira_int->x_max_struct_costs_size)
62 #define init_cost \
63 (this_target_ira_int->x_init_cost)
64 #define temp_costs \
65 (this_target_ira_int->x_temp_costs)
66 #define op_costs \
67 (this_target_ira_int->x_op_costs)
68 #define this_op_costs \
69 (this_target_ira_int->x_this_op_costs)
71 /* Costs of each class for each allocno or pseudo. */
72 static struct costs *costs;
74 /* Accumulated costs of each class for each allocno. */
75 static struct costs *total_allocno_costs;
77 /* It is the current size of struct costs. */
78 static size_t struct_costs_size;
80 /* Return pointer to structure containing costs of allocno or pseudo
81 with given NUM in array ARR. */
82 #define COSTS(arr, num) \
83 ((struct costs *) ((char *) (arr) + (num) * struct_costs_size))
85 /* Return index in COSTS when processing reg with REGNO. */
86 #define COST_INDEX(regno) (allocno_p \
87 ? ALLOCNO_NUM (ira_curr_regno_allocno_map[regno]) \
88 : (int) regno)
90 /* Record register class preferences of each allocno or pseudo. Null
91 value means no preferences. It happens on the 1st iteration of the
92 cost calculation. */
93 static enum reg_class *pref;
95 /* Allocated buffers for pref. */
96 static enum reg_class *pref_buffer;
98 /* Record allocno class of each allocno with the same regno. */
99 static enum reg_class *regno_aclass;
101 /* Record cost gains for not allocating a register with an invariant
102 equivalence. */
103 static int *regno_equiv_gains;
105 /* Execution frequency of the current insn. */
106 static int frequency;
110 /* Info about reg classes whose costs are calculated for a pseudo. */
111 struct cost_classes
113 /* Number of the cost classes in the subsequent array. */
114 int num;
115 /* Container of the cost classes. */
116 enum reg_class classes[N_REG_CLASSES];
117 /* Map reg class -> index of the reg class in the previous array.
118 -1 if it is not a cost class. */
119 int index[N_REG_CLASSES];
120 /* Map hard regno index of first class in array CLASSES containing
121 the hard regno, -1 otherwise. */
122 int hard_regno_index[FIRST_PSEUDO_REGISTER];
125 /* Types of pointers to the structure above. */
126 typedef struct cost_classes *cost_classes_t;
127 typedef const struct cost_classes *const_cost_classes_t;
129 /* Info about cost classes for each pseudo. */
130 static cost_classes_t *regno_cost_classes;
132 /* Helper for cost_classes hashing. */
134 struct cost_classes_hasher : pointer_hash <cost_classes>
136 static inline hashval_t hash (const cost_classes *);
137 static inline bool equal (const cost_classes *, const cost_classes *);
138 static inline void remove (cost_classes *);
141 /* Returns hash value for cost classes info HV. */
142 inline hashval_t
143 cost_classes_hasher::hash (const cost_classes *hv)
145 return iterative_hash (&hv->classes, sizeof (enum reg_class) * hv->num, 0);
148 /* Compares cost classes info HV1 and HV2. */
149 inline bool
150 cost_classes_hasher::equal (const cost_classes *hv1, const cost_classes *hv2)
152 return (hv1->num == hv2->num
153 && memcmp (hv1->classes, hv2->classes,
154 sizeof (enum reg_class) * hv1->num) == 0);
157 /* Delete cost classes info V from the hash table. */
158 inline void
159 cost_classes_hasher::remove (cost_classes *v)
161 ira_free (v);
164 /* Hash table of unique cost classes. */
165 static hash_table<cost_classes_hasher> *cost_classes_htab;
167 /* Map allocno class -> cost classes for pseudo of given allocno
168 class. */
169 static cost_classes_t cost_classes_aclass_cache[N_REG_CLASSES];
171 /* Map mode -> cost classes for pseudo of give mode. */
172 static cost_classes_t cost_classes_mode_cache[MAX_MACHINE_MODE];
174 /* Cost classes that include all classes in ira_important_classes. */
175 static cost_classes all_cost_classes;
177 /* Use the array of classes in CLASSES_PTR to fill out the rest of
178 the structure. */
179 static void
180 complete_cost_classes (cost_classes_t classes_ptr)
182 for (int i = 0; i < N_REG_CLASSES; i++)
183 classes_ptr->index[i] = -1;
184 for (int i = 0; i < FIRST_PSEUDO_REGISTER; i++)
185 classes_ptr->hard_regno_index[i] = -1;
186 for (int i = 0; i < classes_ptr->num; i++)
188 enum reg_class cl = classes_ptr->classes[i];
189 classes_ptr->index[cl] = i;
190 for (int j = ira_class_hard_regs_num[cl] - 1; j >= 0; j--)
192 unsigned int hard_regno = ira_class_hard_regs[cl][j];
193 if (classes_ptr->hard_regno_index[hard_regno] < 0)
194 classes_ptr->hard_regno_index[hard_regno] = i;
199 /* Initialize info about the cost classes for each pseudo. */
200 static void
201 initiate_regno_cost_classes (void)
203 int size = sizeof (cost_classes_t) * max_reg_num ();
205 regno_cost_classes = (cost_classes_t *) ira_allocate (size);
206 memset (regno_cost_classes, 0, size);
207 memset (cost_classes_aclass_cache, 0,
208 sizeof (cost_classes_t) * N_REG_CLASSES);
209 memset (cost_classes_mode_cache, 0,
210 sizeof (cost_classes_t) * MAX_MACHINE_MODE);
211 cost_classes_htab = new hash_table<cost_classes_hasher> (200);
212 all_cost_classes.num = ira_important_classes_num;
213 for (int i = 0; i < ira_important_classes_num; i++)
214 all_cost_classes.classes[i] = ira_important_classes[i];
215 complete_cost_classes (&all_cost_classes);
218 /* Create new cost classes from cost classes FROM and set up members
219 index and hard_regno_index. Return the new classes. The function
220 implements some common code of two functions
221 setup_regno_cost_classes_by_aclass and
222 setup_regno_cost_classes_by_mode. */
223 static cost_classes_t
224 setup_cost_classes (cost_classes_t from)
226 cost_classes_t classes_ptr;
228 classes_ptr = (cost_classes_t) ira_allocate (sizeof (struct cost_classes));
229 classes_ptr->num = from->num;
230 for (int i = 0; i < from->num; i++)
231 classes_ptr->classes[i] = from->classes[i];
232 complete_cost_classes (classes_ptr);
233 return classes_ptr;
236 /* Return a version of FULL that only considers registers in REGS that are
237 valid for mode MODE. Both FULL and the returned class are globally
238 allocated. */
239 static cost_classes_t
240 restrict_cost_classes (cost_classes_t full, machine_mode mode,
241 const_hard_reg_set regs)
243 static struct cost_classes narrow;
244 int map[N_REG_CLASSES];
245 narrow.num = 0;
246 for (int i = 0; i < full->num; i++)
248 /* Assume that we'll drop the class. */
249 map[i] = -1;
251 /* Ignore classes that are too small for the mode. */
252 enum reg_class cl = full->classes[i];
253 if (!contains_reg_of_mode[cl][mode])
254 continue;
256 /* Calculate the set of registers in CL that belong to REGS and
257 are valid for MODE. */
258 HARD_REG_SET valid_for_cl = reg_class_contents[cl] & regs;
259 valid_for_cl &= ~(ira_prohibited_class_mode_regs[cl][mode]
260 | ira_no_alloc_regs);
261 if (hard_reg_set_empty_p (valid_for_cl))
262 continue;
264 /* Don't use this class if the set of valid registers is a subset
265 of an existing class. For example, suppose we have two classes
266 GR_REGS and FR_REGS and a union class GR_AND_FR_REGS. Suppose
267 that the mode changes allowed by FR_REGS are not as general as
268 the mode changes allowed by GR_REGS.
270 In this situation, the mode changes for GR_AND_FR_REGS could
271 either be seen as the union or the intersection of the mode
272 changes allowed by the two subclasses. The justification for
273 the union-based definition would be that, if you want a mode
274 change that's only allowed by GR_REGS, you can pick a register
275 from the GR_REGS subclass. The justification for the
276 intersection-based definition would be that every register
277 from the class would allow the mode change.
279 However, if we have a register that needs to be in GR_REGS,
280 using GR_AND_FR_REGS with the intersection-based definition
281 would be too pessimistic, since it would bring in restrictions
282 that only apply to FR_REGS. Conversely, if we have a register
283 that needs to be in FR_REGS, using GR_AND_FR_REGS with the
284 union-based definition would lose the extra restrictions
285 placed on FR_REGS. GR_AND_FR_REGS is therefore only useful
286 for cases where GR_REGS and FP_REGS are both valid. */
287 int pos;
288 for (pos = 0; pos < narrow.num; ++pos)
290 enum reg_class cl2 = narrow.classes[pos];
291 if (hard_reg_set_subset_p (valid_for_cl, reg_class_contents[cl2]))
292 break;
294 map[i] = pos;
295 if (pos == narrow.num)
297 /* If several classes are equivalent, prefer to use the one
298 that was chosen as the allocno class. */
299 enum reg_class cl2 = ira_allocno_class_translate[cl];
300 if (ira_class_hard_regs_num[cl] == ira_class_hard_regs_num[cl2])
301 cl = cl2;
302 narrow.classes[narrow.num++] = cl;
305 if (narrow.num == full->num)
306 return full;
308 cost_classes **slot = cost_classes_htab->find_slot (&narrow, INSERT);
309 if (*slot == NULL)
311 cost_classes_t classes = setup_cost_classes (&narrow);
312 /* Map equivalent classes to the representative that we chose above. */
313 for (int i = 0; i < ira_important_classes_num; i++)
315 enum reg_class cl = ira_important_classes[i];
316 int index = full->index[cl];
317 if (index >= 0)
318 classes->index[cl] = map[index];
320 *slot = classes;
322 return *slot;
325 /* Setup cost classes for pseudo REGNO whose allocno class is ACLASS.
326 This function is used when we know an initial approximation of
327 allocno class of the pseudo already, e.g. on the second iteration
328 of class cost calculation or after class cost calculation in
329 register-pressure sensitive insn scheduling or register-pressure
330 sensitive loop-invariant motion. */
331 static void
332 setup_regno_cost_classes_by_aclass (int regno, enum reg_class aclass)
334 static struct cost_classes classes;
335 cost_classes_t classes_ptr;
336 enum reg_class cl;
337 int i;
338 cost_classes **slot;
339 HARD_REG_SET temp, temp2;
340 bool exclude_p;
342 if ((classes_ptr = cost_classes_aclass_cache[aclass]) == NULL)
344 temp = reg_class_contents[aclass] & ~ira_no_alloc_regs;
345 /* We exclude classes from consideration which are subsets of
346 ACLASS only if ACLASS is an uniform class. */
347 exclude_p = ira_uniform_class_p[aclass];
348 classes.num = 0;
349 for (i = 0; i < ira_important_classes_num; i++)
351 cl = ira_important_classes[i];
352 if (exclude_p)
354 /* Exclude non-uniform classes which are subsets of
355 ACLASS. */
356 temp2 = reg_class_contents[cl] & ~ira_no_alloc_regs;
357 if (hard_reg_set_subset_p (temp2, temp) && cl != aclass)
358 continue;
360 classes.classes[classes.num++] = cl;
362 slot = cost_classes_htab->find_slot (&classes, INSERT);
363 if (*slot == NULL)
365 classes_ptr = setup_cost_classes (&classes);
366 *slot = classes_ptr;
368 classes_ptr = cost_classes_aclass_cache[aclass] = (cost_classes_t) *slot;
370 if (regno_reg_rtx[regno] != NULL_RTX)
372 /* Restrict the classes to those that are valid for REGNO's mode
373 (which might for example exclude singleton classes if the mode
374 requires two registers). Also restrict the classes to those that
375 are valid for subregs of REGNO. */
376 const HARD_REG_SET *valid_regs = valid_mode_changes_for_regno (regno);
377 if (!valid_regs)
378 valid_regs = &reg_class_contents[ALL_REGS];
379 classes_ptr = restrict_cost_classes (classes_ptr,
380 PSEUDO_REGNO_MODE (regno),
381 *valid_regs);
383 regno_cost_classes[regno] = classes_ptr;
386 /* Setup cost classes for pseudo REGNO with MODE. Usage of MODE can
387 decrease number of cost classes for the pseudo, if hard registers
388 of some important classes cannot hold a value of MODE. So the
389 pseudo cannot get hard register of some important classes and cost
390 calculation for such important classes is only wasting CPU
391 time. */
392 static void
393 setup_regno_cost_classes_by_mode (int regno, machine_mode mode)
395 if (const HARD_REG_SET *valid_regs = valid_mode_changes_for_regno (regno))
396 regno_cost_classes[regno] = restrict_cost_classes (&all_cost_classes,
397 mode, *valid_regs);
398 else
400 if (cost_classes_mode_cache[mode] == NULL)
401 cost_classes_mode_cache[mode]
402 = restrict_cost_classes (&all_cost_classes, mode,
403 reg_class_contents[ALL_REGS]);
404 regno_cost_classes[regno] = cost_classes_mode_cache[mode];
408 /* Finalize info about the cost classes for each pseudo. */
409 static void
410 finish_regno_cost_classes (void)
412 ira_free (regno_cost_classes);
413 delete cost_classes_htab;
414 cost_classes_htab = NULL;
419 /* Compute the cost of loading X into (if TO_P is TRUE) or from (if
420 TO_P is FALSE) a register of class RCLASS in mode MODE. X must not
421 be a pseudo register. */
422 static int
423 copy_cost (rtx x, machine_mode mode, reg_class_t rclass, bool to_p,
424 secondary_reload_info *prev_sri)
426 secondary_reload_info sri;
427 reg_class_t secondary_class = NO_REGS;
429 /* If X is a SCRATCH, there is actually nothing to move since we are
430 assuming optimal allocation. */
431 if (GET_CODE (x) == SCRATCH)
432 return 0;
434 /* Get the class we will actually use for a reload. */
435 rclass = targetm.preferred_reload_class (x, rclass);
437 /* If we need a secondary reload for an intermediate, the cost is
438 that to load the input into the intermediate register, then to
439 copy it. */
440 sri.prev_sri = prev_sri;
441 sri.extra_cost = 0;
442 /* PR 68770: Secondary reload might examine the t_icode field. */
443 sri.t_icode = CODE_FOR_nothing;
445 secondary_class = targetm.secondary_reload (to_p, x, rclass, mode, &sri);
447 if (secondary_class != NO_REGS)
449 ira_init_register_move_cost_if_necessary (mode);
450 return (ira_register_move_cost[mode][(int) secondary_class][(int) rclass]
451 + sri.extra_cost
452 + copy_cost (x, mode, secondary_class, to_p, &sri));
455 /* For memory, use the memory move cost, for (hard) registers, use
456 the cost to move between the register classes, and use 2 for
457 everything else (constants). */
458 if (MEM_P (x) || rclass == NO_REGS)
459 return sri.extra_cost
460 + ira_memory_move_cost[mode][(int) rclass][to_p != 0];
461 else if (REG_P (x))
463 reg_class_t x_class = REGNO_REG_CLASS (REGNO (x));
465 ira_init_register_move_cost_if_necessary (mode);
466 return (sri.extra_cost
467 + ira_register_move_cost[mode][(int) x_class][(int) rclass]);
469 else
470 /* If this is a constant, we may eventually want to call rtx_cost
471 here. */
472 return sri.extra_cost + COSTS_N_INSNS (1);
477 /* Record the cost of using memory or hard registers of various
478 classes for the operands in INSN.
480 N_ALTS is the number of alternatives.
481 N_OPS is the number of operands.
482 OPS is an array of the operands.
483 MODES are the modes of the operands, in case any are VOIDmode.
484 CONSTRAINTS are the constraints to use for the operands. This array
485 is modified by this procedure.
487 This procedure works alternative by alternative. For each
488 alternative we assume that we will be able to allocate all allocnos
489 to their ideal register class and calculate the cost of using that
490 alternative. Then we compute, for each operand that is a
491 pseudo-register, the cost of having the allocno allocated to each
492 register class and using it in that alternative. To this cost is
493 added the cost of the alternative.
495 The cost of each class for this insn is its lowest cost among all
496 the alternatives. */
497 static void
498 record_reg_classes (int n_alts, int n_ops, rtx *ops,
499 machine_mode *modes, const char **constraints,
500 rtx_insn *insn, enum reg_class *pref)
502 int alt;
503 int i, j, k;
504 int insn_allows_mem[MAX_RECOG_OPERANDS];
505 move_table *move_in_cost, *move_out_cost;
506 short (*mem_cost)[2];
507 const char *p;
509 if (ira_dump_file != NULL && internal_flag_ira_verbose > 5)
511 fprintf (ira_dump_file, " Processing insn %u", INSN_UID (insn));
512 if (INSN_CODE (insn) >= 0
513 && (p = get_insn_name (INSN_CODE (insn))) != NULL)
514 fprintf (ira_dump_file, " {%s}", p);
515 fprintf (ira_dump_file, " (freq=%d)\n",
516 REG_FREQ_FROM_BB (BLOCK_FOR_INSN (insn)));
517 dump_insn_slim (ira_dump_file, insn);
520 for (i = 0; i < n_ops; i++)
521 insn_allows_mem[i] = 0;
523 /* Process each alternative, each time minimizing an operand's cost
524 with the cost for each operand in that alternative. */
525 alternative_mask preferred = get_preferred_alternatives (insn);
526 for (alt = 0; alt < n_alts; alt++)
528 enum reg_class classes[MAX_RECOG_OPERANDS];
529 int allows_mem[MAX_RECOG_OPERANDS];
530 enum reg_class rclass;
531 int alt_fail = 0;
532 int alt_cost = 0, op_cost_add;
534 if (!TEST_BIT (preferred, alt))
536 for (i = 0; i < recog_data.n_operands; i++)
537 constraints[i] = skip_alternative (constraints[i]);
539 continue;
542 if (ira_dump_file != NULL && internal_flag_ira_verbose > 5)
544 fprintf (ira_dump_file, " Alt %d:", alt);
545 for (i = 0; i < n_ops; i++)
547 p = constraints[i];
548 if (*p == '\0')
549 continue;
550 fprintf (ira_dump_file, " (%d) ", i);
551 for (; *p != '\0' && *p != ',' && *p != '#'; p++)
552 fputc (*p, ira_dump_file);
554 fprintf (ira_dump_file, "\n");
557 for (i = 0; i < n_ops; i++)
559 unsigned char c;
560 const char *p = constraints[i];
561 rtx op = ops[i];
562 machine_mode mode = modes[i];
563 int allows_addr = 0;
564 int win = 0;
566 /* Initially show we know nothing about the register class. */
567 classes[i] = NO_REGS;
568 allows_mem[i] = 0;
570 /* If this operand has no constraints at all, we can
571 conclude nothing about it since anything is valid. */
572 if (*p == 0)
574 if (REG_P (op) && REGNO (op) >= FIRST_PSEUDO_REGISTER)
575 memset (this_op_costs[i], 0, struct_costs_size);
576 continue;
579 /* If this alternative is only relevant when this operand
580 matches a previous operand, we do different things
581 depending on whether this operand is a allocno-reg or not.
582 We must process any modifiers for the operand before we
583 can make this test. */
584 while (*p == '%' || *p == '=' || *p == '+' || *p == '&')
585 p++;
587 if (p[0] >= '0' && p[0] <= '0' + i)
589 /* Copy class and whether memory is allowed from the
590 matching alternative. Then perform any needed cost
591 computations and/or adjustments. */
592 j = p[0] - '0';
593 classes[i] = classes[j];
594 allows_mem[i] = allows_mem[j];
595 if (allows_mem[i])
596 insn_allows_mem[i] = 1;
598 if (! REG_P (op) || REGNO (op) < FIRST_PSEUDO_REGISTER)
600 /* If this matches the other operand, we have no
601 added cost and we win. */
602 if (rtx_equal_p (ops[j], op))
603 win = 1;
604 /* If we can put the other operand into a register,
605 add to the cost of this alternative the cost to
606 copy this operand to the register used for the
607 other operand. */
608 else if (classes[j] != NO_REGS)
610 alt_cost += copy_cost (op, mode, classes[j], 1, NULL);
611 win = 1;
614 else if (! REG_P (ops[j])
615 || REGNO (ops[j]) < FIRST_PSEUDO_REGISTER)
617 /* This op is an allocno but the one it matches is
618 not. */
620 /* If we can't put the other operand into a
621 register, this alternative can't be used. */
623 if (classes[j] == NO_REGS)
625 alt_fail = 1;
627 else
628 /* Otherwise, add to the cost of this alternative the cost
629 to copy the other operand to the hard register used for
630 this operand. */
632 alt_cost += copy_cost (ops[j], mode, classes[j], 1, NULL);
635 else
637 /* The costs of this operand are not the same as the
638 other operand since move costs are not symmetric.
639 Moreover, if we cannot tie them, this alternative
640 needs to do a copy, which is one insn. */
641 struct costs *pp = this_op_costs[i];
642 int *pp_costs = pp->cost;
643 cost_classes_t cost_classes_ptr
644 = regno_cost_classes[REGNO (op)];
645 enum reg_class *cost_classes = cost_classes_ptr->classes;
646 bool in_p = recog_data.operand_type[i] != OP_OUT;
647 bool out_p = recog_data.operand_type[i] != OP_IN;
648 enum reg_class op_class = classes[i];
650 ira_init_register_move_cost_if_necessary (mode);
651 if (! in_p)
653 ira_assert (out_p);
654 if (op_class == NO_REGS)
656 mem_cost = ira_memory_move_cost[mode];
657 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
659 rclass = cost_classes[k];
660 pp_costs[k] = mem_cost[rclass][0] * frequency;
663 else
665 move_out_cost = ira_may_move_out_cost[mode];
666 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
668 rclass = cost_classes[k];
669 pp_costs[k]
670 = move_out_cost[op_class][rclass] * frequency;
674 else if (! out_p)
676 ira_assert (in_p);
677 if (op_class == NO_REGS)
679 mem_cost = ira_memory_move_cost[mode];
680 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
682 rclass = cost_classes[k];
683 pp_costs[k] = mem_cost[rclass][1] * frequency;
686 else
688 move_in_cost = ira_may_move_in_cost[mode];
689 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
691 rclass = cost_classes[k];
692 pp_costs[k]
693 = move_in_cost[rclass][op_class] * frequency;
697 else
699 if (op_class == NO_REGS)
701 mem_cost = ira_memory_move_cost[mode];
702 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
704 rclass = cost_classes[k];
705 pp_costs[k] = ((mem_cost[rclass][0]
706 + mem_cost[rclass][1])
707 * frequency);
710 else
712 move_in_cost = ira_may_move_in_cost[mode];
713 move_out_cost = ira_may_move_out_cost[mode];
714 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
716 rclass = cost_classes[k];
717 pp_costs[k] = ((move_in_cost[rclass][op_class]
718 + move_out_cost[op_class][rclass])
719 * frequency);
724 /* If the alternative actually allows memory, make
725 things a bit cheaper since we won't need an extra
726 insn to load it. */
727 pp->mem_cost
728 = ((out_p ? ira_memory_move_cost[mode][op_class][0] : 0)
729 + (in_p ? ira_memory_move_cost[mode][op_class][1] : 0)
730 - allows_mem[i]) * frequency;
732 /* If we have assigned a class to this allocno in
733 our first pass, add a cost to this alternative
734 corresponding to what we would add if this
735 allocno were not in the appropriate class. */
736 if (pref)
738 enum reg_class pref_class = pref[COST_INDEX (REGNO (op))];
740 if (pref_class == NO_REGS)
741 alt_cost
742 += ((out_p
743 ? ira_memory_move_cost[mode][op_class][0] : 0)
744 + (in_p
745 ? ira_memory_move_cost[mode][op_class][1]
746 : 0));
747 else if (ira_reg_class_intersect
748 [pref_class][op_class] == NO_REGS)
749 alt_cost
750 += ira_register_move_cost[mode][pref_class][op_class];
752 if (REGNO (ops[i]) != REGNO (ops[j])
753 && ! find_reg_note (insn, REG_DEAD, op))
754 alt_cost += 2;
756 p++;
760 /* Scan all the constraint letters. See if the operand
761 matches any of the constraints. Collect the valid
762 register classes and see if this operand accepts
763 memory. */
764 while ((c = *p))
766 switch (c)
768 case '*':
769 /* Ignore the next letter for this pass. */
770 c = *++p;
771 break;
773 case '^':
774 alt_cost += 2;
775 break;
777 case '?':
778 alt_cost += 2;
779 break;
781 case 'g':
782 if (MEM_P (op)
783 || (CONSTANT_P (op)
784 && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (op))))
785 win = 1;
786 insn_allows_mem[i] = allows_mem[i] = 1;
787 classes[i] = ira_reg_class_subunion[classes[i]][GENERAL_REGS];
788 break;
790 default:
791 enum constraint_num cn = lookup_constraint (p);
792 enum reg_class cl;
793 switch (get_constraint_type (cn))
795 case CT_REGISTER:
796 cl = reg_class_for_constraint (cn);
797 if (cl != NO_REGS)
798 classes[i] = ira_reg_class_subunion[classes[i]][cl];
799 break;
801 case CT_CONST_INT:
802 if (CONST_INT_P (op)
803 && insn_const_int_ok_for_constraint (INTVAL (op), cn))
804 win = 1;
805 break;
807 case CT_MEMORY:
808 case CT_RELAXED_MEMORY:
809 /* Every MEM can be reloaded to fit. */
810 insn_allows_mem[i] = allows_mem[i] = 1;
811 if (MEM_P (op))
812 win = 1;
813 break;
815 case CT_SPECIAL_MEMORY:
816 insn_allows_mem[i] = allows_mem[i] = 1;
817 if (MEM_P (extract_mem_from_operand (op))
818 && constraint_satisfied_p (op, cn))
819 win = 1;
820 break;
822 case CT_ADDRESS:
823 /* Every address can be reloaded to fit. */
824 allows_addr = 1;
825 if (address_operand (op, GET_MODE (op))
826 || constraint_satisfied_p (op, cn))
827 win = 1;
828 /* We know this operand is an address, so we
829 want it to be allocated to a hard register
830 that can be the base of an address,
831 i.e. BASE_REG_CLASS. */
832 classes[i]
833 = ira_reg_class_subunion[classes[i]]
834 [base_reg_class (VOIDmode, ADDR_SPACE_GENERIC,
835 ADDRESS, SCRATCH)];
836 break;
838 case CT_FIXED_FORM:
839 if (constraint_satisfied_p (op, cn))
840 win = 1;
841 break;
843 break;
845 p += CONSTRAINT_LEN (c, p);
846 if (c == ',')
847 break;
850 constraints[i] = p;
852 if (alt_fail)
853 break;
855 /* How we account for this operand now depends on whether it
856 is a pseudo register or not. If it is, we first check if
857 any register classes are valid. If not, we ignore this
858 alternative, since we want to assume that all allocnos get
859 allocated for register preferencing. If some register
860 class is valid, compute the costs of moving the allocno
861 into that class. */
862 if (REG_P (op) && REGNO (op) >= FIRST_PSEUDO_REGISTER)
864 if (classes[i] == NO_REGS && ! allows_mem[i])
866 /* We must always fail if the operand is a REG, but
867 we did not find a suitable class and memory is
868 not allowed.
870 Otherwise we may perform an uninitialized read
871 from this_op_costs after the `continue' statement
872 below. */
873 alt_fail = 1;
875 else
877 unsigned int regno = REGNO (op);
878 struct costs *pp = this_op_costs[i];
879 int *pp_costs = pp->cost;
880 cost_classes_t cost_classes_ptr = regno_cost_classes[regno];
881 enum reg_class *cost_classes = cost_classes_ptr->classes;
882 bool in_p = recog_data.operand_type[i] != OP_OUT;
883 bool out_p = recog_data.operand_type[i] != OP_IN;
884 enum reg_class op_class = classes[i];
886 ira_init_register_move_cost_if_necessary (mode);
887 if (! in_p)
889 ira_assert (out_p);
890 if (op_class == NO_REGS)
892 mem_cost = ira_memory_move_cost[mode];
893 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
895 rclass = cost_classes[k];
896 pp_costs[k] = mem_cost[rclass][0] * frequency;
899 else
901 move_out_cost = ira_may_move_out_cost[mode];
902 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
904 rclass = cost_classes[k];
905 pp_costs[k]
906 = move_out_cost[op_class][rclass] * frequency;
910 else if (! out_p)
912 ira_assert (in_p);
913 if (op_class == NO_REGS)
915 mem_cost = ira_memory_move_cost[mode];
916 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
918 rclass = cost_classes[k];
919 pp_costs[k] = mem_cost[rclass][1] * frequency;
922 else
924 move_in_cost = ira_may_move_in_cost[mode];
925 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
927 rclass = cost_classes[k];
928 pp_costs[k]
929 = move_in_cost[rclass][op_class] * frequency;
933 else
935 if (op_class == NO_REGS)
937 mem_cost = ira_memory_move_cost[mode];
938 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
940 rclass = cost_classes[k];
941 pp_costs[k] = ((mem_cost[rclass][0]
942 + mem_cost[rclass][1])
943 * frequency);
946 else
948 move_in_cost = ira_may_move_in_cost[mode];
949 move_out_cost = ira_may_move_out_cost[mode];
950 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
952 rclass = cost_classes[k];
953 pp_costs[k] = ((move_in_cost[rclass][op_class]
954 + move_out_cost[op_class][rclass])
955 * frequency);
960 if (op_class == NO_REGS)
961 /* Although we don't need insn to reload from
962 memory, still accessing memory is usually more
963 expensive than a register. */
964 pp->mem_cost = frequency;
965 else
966 /* If the alternative actually allows memory, make
967 things a bit cheaper since we won't need an
968 extra insn to load it. */
969 pp->mem_cost
970 = ((out_p ? ira_memory_move_cost[mode][op_class][0] : 0)
971 + (in_p ? ira_memory_move_cost[mode][op_class][1] : 0)
972 - allows_mem[i]) * frequency;
973 /* If we have assigned a class to this allocno in
974 our first pass, add a cost to this alternative
975 corresponding to what we would add if this
976 allocno were not in the appropriate class. */
977 if (pref)
979 enum reg_class pref_class = pref[COST_INDEX (REGNO (op))];
981 if (pref_class == NO_REGS)
983 if (op_class != NO_REGS)
984 alt_cost
985 += ((out_p
986 ? ira_memory_move_cost[mode][op_class][0]
987 : 0)
988 + (in_p
989 ? ira_memory_move_cost[mode][op_class][1]
990 : 0));
992 else if (op_class == NO_REGS)
993 alt_cost
994 += ((out_p
995 ? ira_memory_move_cost[mode][pref_class][1]
996 : 0)
997 + (in_p
998 ? ira_memory_move_cost[mode][pref_class][0]
999 : 0));
1000 else if (ira_reg_class_intersect[pref_class][op_class]
1001 == NO_REGS)
1002 alt_cost += (ira_register_move_cost
1003 [mode][pref_class][op_class]);
1008 /* Otherwise, if this alternative wins, either because we
1009 have already determined that or if we have a hard
1010 register of the proper class, there is no cost for this
1011 alternative. */
1012 else if (win || (REG_P (op)
1013 && reg_fits_class_p (op, classes[i],
1014 0, GET_MODE (op))))
1017 /* If registers are valid, the cost of this alternative
1018 includes copying the object to and/or from a
1019 register. */
1020 else if (classes[i] != NO_REGS)
1022 if (recog_data.operand_type[i] != OP_OUT)
1023 alt_cost += copy_cost (op, mode, classes[i], 1, NULL);
1025 if (recog_data.operand_type[i] != OP_IN)
1026 alt_cost += copy_cost (op, mode, classes[i], 0, NULL);
1028 /* The only other way this alternative can be used is if
1029 this is a constant that could be placed into memory. */
1030 else if (CONSTANT_P (op) && (allows_addr || allows_mem[i]))
1031 alt_cost += ira_memory_move_cost[mode][classes[i]][1];
1032 else
1033 alt_fail = 1;
1035 if (alt_fail)
1036 break;
1039 if (alt_fail)
1041 /* The loop above might have exited early once the failure
1042 was seen. Skip over the constraints for the remaining
1043 operands. */
1044 i += 1;
1045 for (; i < n_ops; ++i)
1046 constraints[i] = skip_alternative (constraints[i]);
1047 continue;
1050 op_cost_add = alt_cost * frequency;
1051 /* Finally, update the costs with the information we've
1052 calculated about this alternative. */
1053 for (i = 0; i < n_ops; i++)
1054 if (REG_P (ops[i]) && REGNO (ops[i]) >= FIRST_PSEUDO_REGISTER)
1056 int old_cost;
1057 bool cost_change_p = false;
1058 struct costs *pp = op_costs[i], *qq = this_op_costs[i];
1059 int *pp_costs = pp->cost, *qq_costs = qq->cost;
1060 int scale = 1 + (recog_data.operand_type[i] == OP_INOUT);
1061 cost_classes_t cost_classes_ptr
1062 = regno_cost_classes[REGNO (ops[i])];
1064 old_cost = pp->mem_cost;
1065 pp->mem_cost = MIN (old_cost,
1066 (qq->mem_cost + op_cost_add) * scale);
1068 if (ira_dump_file != NULL && internal_flag_ira_verbose > 5
1069 && pp->mem_cost < old_cost)
1071 cost_change_p = true;
1072 fprintf (ira_dump_file, " op %d(r=%u) new costs MEM:%d",
1073 i, REGNO(ops[i]), pp->mem_cost);
1075 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
1077 old_cost = pp_costs[k];
1078 pp_costs[k]
1079 = MIN (old_cost, (qq_costs[k] + op_cost_add) * scale);
1080 if (ira_dump_file != NULL && internal_flag_ira_verbose > 5
1081 && pp_costs[k] < old_cost)
1083 if (!cost_change_p)
1084 fprintf (ira_dump_file, " op %d(r=%u) new costs",
1085 i, REGNO(ops[i]));
1086 cost_change_p = true;
1087 fprintf (ira_dump_file, " %s:%d",
1088 reg_class_names[cost_classes_ptr->classes[k]],
1089 pp_costs[k]);
1092 if (ira_dump_file != NULL && internal_flag_ira_verbose > 5
1093 && cost_change_p)
1094 fprintf (ira_dump_file, "\n");
1098 if (allocno_p)
1099 for (i = 0; i < n_ops; i++)
1101 ira_allocno_t a;
1102 rtx op = ops[i];
1104 if (! REG_P (op) || REGNO (op) < FIRST_PSEUDO_REGISTER)
1105 continue;
1106 a = ira_curr_regno_allocno_map [REGNO (op)];
1107 if (! ALLOCNO_BAD_SPILL_P (a) && insn_allows_mem[i] == 0)
1108 ALLOCNO_BAD_SPILL_P (a) = true;
1115 /* Wrapper around REGNO_OK_FOR_INDEX_P, to allow pseudo registers. */
1116 static inline bool
1117 ok_for_index_p_nonstrict (rtx reg)
1119 unsigned regno = REGNO (reg);
1121 return regno >= FIRST_PSEUDO_REGISTER || REGNO_OK_FOR_INDEX_P (regno);
1124 /* A version of regno_ok_for_base_p for use here, when all
1125 pseudo-registers should count as OK. Arguments as for
1126 regno_ok_for_base_p. */
1127 static inline bool
1128 ok_for_base_p_nonstrict (rtx reg, machine_mode mode, addr_space_t as,
1129 enum rtx_code outer_code, enum rtx_code index_code)
1131 unsigned regno = REGNO (reg);
1133 if (regno >= FIRST_PSEUDO_REGISTER)
1134 return true;
1135 return ok_for_base_p_1 (regno, mode, as, outer_code, index_code);
1138 /* Record the pseudo registers we must reload into hard registers in a
1139 subexpression of a memory address, X.
1141 If CONTEXT is 0, we are looking at the base part of an address,
1142 otherwise we are looking at the index part.
1144 MODE and AS are the mode and address space of the memory reference;
1145 OUTER_CODE and INDEX_CODE give the context that the rtx appears in.
1146 These four arguments are passed down to base_reg_class.
1148 SCALE is twice the amount to multiply the cost by (it is twice so
1149 we can represent half-cost adjustments). */
1150 static void
1151 record_address_regs (machine_mode mode, addr_space_t as, rtx x,
1152 int context, enum rtx_code outer_code,
1153 enum rtx_code index_code, int scale)
1155 enum rtx_code code = GET_CODE (x);
1156 enum reg_class rclass;
1158 if (context == 1)
1159 rclass = INDEX_REG_CLASS;
1160 else
1161 rclass = base_reg_class (mode, as, outer_code, index_code);
1163 switch (code)
1165 case CONST_INT:
1166 case CONST:
1167 case PC:
1168 case SYMBOL_REF:
1169 case LABEL_REF:
1170 return;
1172 case PLUS:
1173 /* When we have an address that is a sum, we must determine
1174 whether registers are "base" or "index" regs. If there is a
1175 sum of two registers, we must choose one to be the "base".
1176 Luckily, we can use the REG_POINTER to make a good choice
1177 most of the time. We only need to do this on machines that
1178 can have two registers in an address and where the base and
1179 index register classes are different.
1181 ??? This code used to set REGNO_POINTER_FLAG in some cases,
1182 but that seems bogus since it should only be set when we are
1183 sure the register is being used as a pointer. */
1185 rtx arg0 = XEXP (x, 0);
1186 rtx arg1 = XEXP (x, 1);
1187 enum rtx_code code0 = GET_CODE (arg0);
1188 enum rtx_code code1 = GET_CODE (arg1);
1190 /* Look inside subregs. */
1191 if (code0 == SUBREG)
1192 arg0 = SUBREG_REG (arg0), code0 = GET_CODE (arg0);
1193 if (code1 == SUBREG)
1194 arg1 = SUBREG_REG (arg1), code1 = GET_CODE (arg1);
1196 /* If index registers do not appear, or coincide with base registers,
1197 just record registers in any non-constant operands. We
1198 assume here, as well as in the tests below, that all
1199 addresses are in canonical form. */
1200 if (MAX_REGS_PER_ADDRESS == 1
1201 || INDEX_REG_CLASS == base_reg_class (VOIDmode, as, PLUS, SCRATCH))
1203 record_address_regs (mode, as, arg0, context, PLUS, code1, scale);
1204 if (! CONSTANT_P (arg1))
1205 record_address_regs (mode, as, arg1, context, PLUS, code0, scale);
1208 /* If the second operand is a constant integer, it doesn't
1209 change what class the first operand must be. */
1210 else if (CONST_SCALAR_INT_P (arg1))
1211 record_address_regs (mode, as, arg0, context, PLUS, code1, scale);
1212 /* If the second operand is a symbolic constant, the first
1213 operand must be an index register. */
1214 else if (code1 == SYMBOL_REF || code1 == CONST || code1 == LABEL_REF)
1215 record_address_regs (mode, as, arg0, 1, PLUS, code1, scale);
1216 /* If both operands are registers but one is already a hard
1217 register of index or reg-base class, give the other the
1218 class that the hard register is not. */
1219 else if (code0 == REG && code1 == REG
1220 && REGNO (arg0) < FIRST_PSEUDO_REGISTER
1221 && (ok_for_base_p_nonstrict (arg0, mode, as, PLUS, REG)
1222 || ok_for_index_p_nonstrict (arg0)))
1223 record_address_regs (mode, as, arg1,
1224 ok_for_base_p_nonstrict (arg0, mode, as,
1225 PLUS, REG) ? 1 : 0,
1226 PLUS, REG, scale);
1227 else if (code0 == REG && code1 == REG
1228 && REGNO (arg1) < FIRST_PSEUDO_REGISTER
1229 && (ok_for_base_p_nonstrict (arg1, mode, as, PLUS, REG)
1230 || ok_for_index_p_nonstrict (arg1)))
1231 record_address_regs (mode, as, arg0,
1232 ok_for_base_p_nonstrict (arg1, mode, as,
1233 PLUS, REG) ? 1 : 0,
1234 PLUS, REG, scale);
1235 /* If one operand is known to be a pointer, it must be the
1236 base with the other operand the index. Likewise if the
1237 other operand is a MULT. */
1238 else if ((code0 == REG && REG_POINTER (arg0)) || code1 == MULT)
1240 record_address_regs (mode, as, arg0, 0, PLUS, code1, scale);
1241 record_address_regs (mode, as, arg1, 1, PLUS, code0, scale);
1243 else if ((code1 == REG && REG_POINTER (arg1)) || code0 == MULT)
1245 record_address_regs (mode, as, arg0, 1, PLUS, code1, scale);
1246 record_address_regs (mode, as, arg1, 0, PLUS, code0, scale);
1248 /* Otherwise, count equal chances that each might be a base or
1249 index register. This case should be rare. */
1250 else
1252 record_address_regs (mode, as, arg0, 0, PLUS, code1, scale / 2);
1253 record_address_regs (mode, as, arg0, 1, PLUS, code1, scale / 2);
1254 record_address_regs (mode, as, arg1, 0, PLUS, code0, scale / 2);
1255 record_address_regs (mode, as, arg1, 1, PLUS, code0, scale / 2);
1258 break;
1260 /* Double the importance of an allocno that is incremented or
1261 decremented, since it would take two extra insns if it ends
1262 up in the wrong place. */
1263 case POST_MODIFY:
1264 case PRE_MODIFY:
1265 record_address_regs (mode, as, XEXP (x, 0), 0, code,
1266 GET_CODE (XEXP (XEXP (x, 1), 1)), 2 * scale);
1267 if (REG_P (XEXP (XEXP (x, 1), 1)))
1268 record_address_regs (mode, as, XEXP (XEXP (x, 1), 1), 1, code, REG,
1269 2 * scale);
1270 break;
1272 case POST_INC:
1273 case PRE_INC:
1274 case POST_DEC:
1275 case PRE_DEC:
1276 /* Double the importance of an allocno that is incremented or
1277 decremented, since it would take two extra insns if it ends
1278 up in the wrong place. */
1279 record_address_regs (mode, as, XEXP (x, 0), 0, code, SCRATCH, 2 * scale);
1280 break;
1282 case REG:
1284 struct costs *pp;
1285 int *pp_costs;
1286 enum reg_class i;
1287 int k, regno, add_cost;
1288 cost_classes_t cost_classes_ptr;
1289 enum reg_class *cost_classes;
1290 move_table *move_in_cost;
1292 if (REGNO (x) < FIRST_PSEUDO_REGISTER)
1293 break;
1295 regno = REGNO (x);
1296 if (allocno_p)
1297 ALLOCNO_BAD_SPILL_P (ira_curr_regno_allocno_map[regno]) = true;
1298 pp = COSTS (costs, COST_INDEX (regno));
1299 add_cost = (ira_memory_move_cost[Pmode][rclass][1] * scale) / 2;
1300 if (INT_MAX - add_cost < pp->mem_cost)
1301 pp->mem_cost = INT_MAX;
1302 else
1303 pp->mem_cost += add_cost;
1304 cost_classes_ptr = regno_cost_classes[regno];
1305 cost_classes = cost_classes_ptr->classes;
1306 pp_costs = pp->cost;
1307 ira_init_register_move_cost_if_necessary (Pmode);
1308 move_in_cost = ira_may_move_in_cost[Pmode];
1309 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
1311 i = cost_classes[k];
1312 add_cost = (move_in_cost[i][rclass] * scale) / 2;
1313 if (INT_MAX - add_cost < pp_costs[k])
1314 pp_costs[k] = INT_MAX;
1315 else
1316 pp_costs[k] += add_cost;
1319 break;
1321 default:
1323 const char *fmt = GET_RTX_FORMAT (code);
1324 int i;
1325 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1326 if (fmt[i] == 'e')
1327 record_address_regs (mode, as, XEXP (x, i), context, code, SCRATCH,
1328 scale);
1335 /* Calculate the costs of insn operands. */
1336 static void
1337 record_operand_costs (rtx_insn *insn, enum reg_class *pref)
1339 const char *constraints[MAX_RECOG_OPERANDS];
1340 machine_mode modes[MAX_RECOG_OPERANDS];
1341 rtx set;
1342 int i;
1344 if ((set = single_set (insn)) != NULL_RTX
1345 /* In rare cases the single set insn might have less 2 operands
1346 as the source can be a fixed special reg. */
1347 && recog_data.n_operands > 1
1348 && recog_data.operand[0] == SET_DEST (set)
1349 && recog_data.operand[1] == SET_SRC (set))
1351 int regno, other_regno;
1352 rtx dest = SET_DEST (set);
1353 rtx src = SET_SRC (set);
1355 if (GET_CODE (dest) == SUBREG
1356 && known_eq (GET_MODE_SIZE (GET_MODE (dest)),
1357 GET_MODE_SIZE (GET_MODE (SUBREG_REG (dest)))))
1358 dest = SUBREG_REG (dest);
1359 if (GET_CODE (src) == SUBREG
1360 && known_eq (GET_MODE_SIZE (GET_MODE (src)),
1361 GET_MODE_SIZE (GET_MODE (SUBREG_REG (src)))))
1362 src = SUBREG_REG (src);
1363 if (REG_P (src) && REG_P (dest)
1364 && (((regno = REGNO (src)) >= FIRST_PSEUDO_REGISTER
1365 && (other_regno = REGNO (dest)) < FIRST_PSEUDO_REGISTER)
1366 || ((regno = REGNO (dest)) >= FIRST_PSEUDO_REGISTER
1367 && (other_regno = REGNO (src)) < FIRST_PSEUDO_REGISTER)))
1369 machine_mode mode = GET_MODE (SET_SRC (set)), cost_mode = mode;
1370 machine_mode hard_reg_mode = GET_MODE(regno_reg_rtx[other_regno]);
1371 poly_int64 pmode_size = GET_MODE_SIZE (mode);
1372 poly_int64 phard_reg_mode_size = GET_MODE_SIZE (hard_reg_mode);
1373 HOST_WIDE_INT mode_size, hard_reg_mode_size;
1374 cost_classes_t cost_classes_ptr = regno_cost_classes[regno];
1375 enum reg_class *cost_classes = cost_classes_ptr->classes;
1376 reg_class_t rclass, hard_reg_class, bigger_hard_reg_class;
1377 int cost_factor = 1, cost, k;
1378 move_table *move_costs;
1379 bool dead_p = find_regno_note (insn, REG_DEAD, REGNO (src));
1381 hard_reg_class = REGNO_REG_CLASS (other_regno);
1382 bigger_hard_reg_class = ira_pressure_class_translate[hard_reg_class];
1383 /* Target code may return any cost for mode which does not fit the
1384 hard reg class (e.g. DImode for AREG on i386). Check this and use
1385 a bigger class to get the right cost. */
1386 if (bigger_hard_reg_class != NO_REGS
1387 && ! ira_hard_reg_in_set_p (other_regno, mode,
1388 reg_class_contents[hard_reg_class]))
1389 hard_reg_class = bigger_hard_reg_class;
1390 ira_init_register_move_cost_if_necessary (mode);
1391 ira_init_register_move_cost_if_necessary (hard_reg_mode);
1392 /* Use smaller movement cost for natural hard reg mode or its mode as
1393 operand. */
1394 if (pmode_size.is_constant (&mode_size)
1395 && phard_reg_mode_size.is_constant (&hard_reg_mode_size))
1397 /* Assume we are moving in the natural modes: */
1398 cost_factor = mode_size / hard_reg_mode_size;
1399 if (mode_size % hard_reg_mode_size != 0)
1400 cost_factor++;
1401 if (cost_factor
1402 * (ira_register_move_cost
1403 [hard_reg_mode][hard_reg_class][hard_reg_class])
1404 < (ira_register_move_cost
1405 [mode][hard_reg_class][hard_reg_class]))
1406 cost_mode = hard_reg_mode;
1407 else
1408 cost_factor = 1;
1410 move_costs = ira_register_move_cost[cost_mode];
1411 i = regno == (int) REGNO (src) ? 1 : 0;
1412 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
1414 rclass = cost_classes[k];
1415 cost = (i == 0
1416 ? move_costs[hard_reg_class][rclass]
1417 : move_costs[rclass][hard_reg_class]);
1418 cost *= cost_factor;
1419 op_costs[i]->cost[k] = cost * frequency;
1420 /* If this insn is a single set copying operand 1 to
1421 operand 0 and one operand is an allocno with the
1422 other a hard reg or an allocno that prefers a hard
1423 register that is in its own register class then we
1424 may want to adjust the cost of that register class to
1427 Avoid the adjustment if the source does not die to
1428 avoid stressing of register allocator by preferencing
1429 two colliding registers into single class. */
1430 if (dead_p
1431 && TEST_HARD_REG_BIT (reg_class_contents[rclass], other_regno)
1432 && (reg_class_size[(int) rclass]
1433 == (ira_reg_class_max_nregs
1434 [(int) rclass][(int) GET_MODE(src)])))
1436 if (reg_class_size[rclass] == 1)
1437 op_costs[i]->cost[k] = -frequency;
1438 else if (in_hard_reg_set_p (reg_class_contents[rclass],
1439 GET_MODE(src), other_regno))
1440 op_costs[i]->cost[k] = -frequency;
1443 op_costs[i]->mem_cost
1444 = ira_memory_move_cost[mode][hard_reg_class][i] * frequency;
1445 return;
1449 for (i = 0; i < recog_data.n_operands; i++)
1451 constraints[i] = recog_data.constraints[i];
1452 modes[i] = recog_data.operand_mode[i];
1455 /* If we get here, we are set up to record the costs of all the
1456 operands for this insn. Start by initializing the costs. Then
1457 handle any address registers. Finally record the desired classes
1458 for any allocnos, doing it twice if some pair of operands are
1459 commutative. */
1460 for (i = 0; i < recog_data.n_operands; i++)
1462 rtx op_mem = extract_mem_from_operand (recog_data.operand[i]);
1463 memcpy (op_costs[i], init_cost, struct_costs_size);
1465 if (GET_CODE (recog_data.operand[i]) == SUBREG)
1466 recog_data.operand[i] = SUBREG_REG (recog_data.operand[i]);
1468 if (MEM_P (op_mem))
1469 record_address_regs (GET_MODE (op_mem),
1470 MEM_ADDR_SPACE (op_mem),
1471 XEXP (op_mem, 0),
1472 0, MEM, SCRATCH, frequency * 2);
1473 else if (constraints[i][0] == 'p'
1474 || (insn_extra_address_constraint
1475 (lookup_constraint (constraints[i]))))
1476 record_address_regs (VOIDmode, ADDR_SPACE_GENERIC,
1477 recog_data.operand[i], 0, ADDRESS, SCRATCH,
1478 frequency * 2);
1481 /* Check for commutative in a separate loop so everything will have
1482 been initialized. We must do this even if one operand is a
1483 constant--see addsi3 in m68k.md. */
1484 for (i = 0; i < (int) recog_data.n_operands - 1; i++)
1485 if (constraints[i][0] == '%')
1487 const char *xconstraints[MAX_RECOG_OPERANDS];
1488 int j;
1490 /* Handle commutative operands by swapping the
1491 constraints. We assume the modes are the same. */
1492 for (j = 0; j < recog_data.n_operands; j++)
1493 xconstraints[j] = constraints[j];
1495 xconstraints[i] = constraints[i+1];
1496 xconstraints[i+1] = constraints[i];
1497 record_reg_classes (recog_data.n_alternatives, recog_data.n_operands,
1498 recog_data.operand, modes,
1499 xconstraints, insn, pref);
1501 record_reg_classes (recog_data.n_alternatives, recog_data.n_operands,
1502 recog_data.operand, modes,
1503 constraints, insn, pref);
1508 /* Process one insn INSN. Scan it and record each time it would save
1509 code to put a certain allocnos in a certain class. Return the last
1510 insn processed, so that the scan can be continued from there. */
1511 static rtx_insn *
1512 scan_one_insn (rtx_insn *insn)
1514 enum rtx_code pat_code;
1515 rtx set, note;
1516 int i, k;
1517 bool counted_mem;
1519 if (!NONDEBUG_INSN_P (insn))
1520 return insn;
1522 pat_code = GET_CODE (PATTERN (insn));
1523 if (pat_code == ASM_INPUT)
1524 return insn;
1526 /* If INSN is a USE/CLOBBER of a pseudo in a mode M then go ahead
1527 and initialize the register move costs of mode M.
1529 The pseudo may be related to another pseudo via a copy (implicit or
1530 explicit) and if there are no mode M uses/sets of the original
1531 pseudo, then we may leave the register move costs uninitialized for
1532 mode M. */
1533 if (pat_code == USE || pat_code == CLOBBER)
1535 rtx x = XEXP (PATTERN (insn), 0);
1536 if (GET_CODE (x) == REG
1537 && REGNO (x) >= FIRST_PSEUDO_REGISTER
1538 && have_regs_of_mode[GET_MODE (x)])
1539 ira_init_register_move_cost_if_necessary (GET_MODE (x));
1540 return insn;
1543 counted_mem = false;
1544 set = single_set (insn);
1545 extract_insn (insn);
1547 /* If this insn loads a parameter from its stack slot, then it
1548 represents a savings, rather than a cost, if the parameter is
1549 stored in memory. Record this fact.
1551 Similarly if we're loading other constants from memory (constant
1552 pool, TOC references, small data areas, etc) and this is the only
1553 assignment to the destination pseudo.
1555 Don't do this if SET_SRC (set) isn't a general operand, if it is
1556 a memory requiring special instructions to load it, decreasing
1557 mem_cost might result in it being loaded using the specialized
1558 instruction into a register, then stored into stack and loaded
1559 again from the stack. See PR52208.
1561 Don't do this if SET_SRC (set) has side effect. See PR56124. */
1562 if (set != 0 && REG_P (SET_DEST (set)) && MEM_P (SET_SRC (set))
1563 && (note = find_reg_note (insn, REG_EQUIV, NULL_RTX)) != NULL_RTX
1564 && ((MEM_P (XEXP (note, 0))
1565 && !side_effects_p (SET_SRC (set)))
1566 || (CONSTANT_P (XEXP (note, 0))
1567 && targetm.legitimate_constant_p (GET_MODE (SET_DEST (set)),
1568 XEXP (note, 0))
1569 && REG_N_SETS (REGNO (SET_DEST (set))) == 1))
1570 && general_operand (SET_SRC (set), GET_MODE (SET_SRC (set)))
1571 /* LRA does not use equiv with a symbol for PIC code. */
1572 && (! ira_use_lra_p || ! pic_offset_table_rtx
1573 || ! contains_symbol_ref_p (XEXP (note, 0))))
1575 enum reg_class cl = GENERAL_REGS;
1576 rtx reg = SET_DEST (set);
1577 int num = COST_INDEX (REGNO (reg));
1579 COSTS (costs, num)->mem_cost
1580 -= ira_memory_move_cost[GET_MODE (reg)][cl][1] * frequency;
1581 record_address_regs (GET_MODE (SET_SRC (set)),
1582 MEM_ADDR_SPACE (SET_SRC (set)),
1583 XEXP (SET_SRC (set), 0), 0, MEM, SCRATCH,
1584 frequency * 2);
1585 counted_mem = true;
1588 record_operand_costs (insn, pref);
1590 if (ira_dump_file != NULL && internal_flag_ira_verbose > 5)
1592 const char *p;
1593 fprintf (ira_dump_file, " Final costs after insn %u", INSN_UID (insn));
1594 if (INSN_CODE (insn) >= 0
1595 && (p = get_insn_name (INSN_CODE (insn))) != NULL)
1596 fprintf (ira_dump_file, " {%s}", p);
1597 fprintf (ira_dump_file, " (freq=%d)\n",
1598 REG_FREQ_FROM_BB (BLOCK_FOR_INSN (insn)));
1599 dump_insn_slim (ira_dump_file, insn);
1602 /* Now add the cost for each operand to the total costs for its
1603 allocno. */
1604 for (i = 0; i < recog_data.n_operands; i++)
1606 rtx op = recog_data.operand[i];
1608 if (GET_CODE (op) == SUBREG)
1609 op = SUBREG_REG (op);
1610 if (REG_P (op) && REGNO (op) >= FIRST_PSEUDO_REGISTER)
1612 int regno = REGNO (op);
1613 struct costs *p = COSTS (costs, COST_INDEX (regno));
1614 struct costs *q = op_costs[i];
1615 int *p_costs = p->cost, *q_costs = q->cost;
1616 cost_classes_t cost_classes_ptr = regno_cost_classes[regno];
1617 int add_cost = 0;
1619 /* If the already accounted for the memory "cost" above, don't
1620 do so again. */
1621 if (!counted_mem)
1623 add_cost = q->mem_cost;
1624 if (add_cost > 0 && INT_MAX - add_cost < p->mem_cost)
1625 p->mem_cost = INT_MAX;
1626 else
1627 p->mem_cost += add_cost;
1629 if (ira_dump_file != NULL && internal_flag_ira_verbose > 5)
1631 fprintf (ira_dump_file, " op %d(r=%u) MEM:%d(+%d)",
1632 i, REGNO(op), p->mem_cost, add_cost);
1634 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
1636 add_cost = q_costs[k];
1637 if (add_cost > 0 && INT_MAX - add_cost < p_costs[k])
1638 p_costs[k] = INT_MAX;
1639 else
1640 p_costs[k] += add_cost;
1641 if (ira_dump_file != NULL && internal_flag_ira_verbose > 5)
1643 fprintf (ira_dump_file, " %s:%d(+%d)",
1644 reg_class_names[cost_classes_ptr->classes[k]],
1645 p_costs[k], add_cost);
1648 if (ira_dump_file != NULL && internal_flag_ira_verbose > 5)
1649 fprintf (ira_dump_file, "\n");
1652 return insn;
1657 /* Print allocnos costs to file F. */
1658 static void
1659 print_allocno_costs (FILE *f)
1661 int k;
1662 ira_allocno_t a;
1663 ira_allocno_iterator ai;
1665 ira_assert (allocno_p);
1666 fprintf (f, "\n");
1667 FOR_EACH_ALLOCNO (a, ai)
1669 int i, rclass;
1670 basic_block bb;
1671 int regno = ALLOCNO_REGNO (a);
1672 cost_classes_t cost_classes_ptr = regno_cost_classes[regno];
1673 enum reg_class *cost_classes = cost_classes_ptr->classes;
1675 i = ALLOCNO_NUM (a);
1676 fprintf (f, " a%d(r%d,", i, regno);
1677 if ((bb = ALLOCNO_LOOP_TREE_NODE (a)->bb) != NULL)
1678 fprintf (f, "b%d", bb->index);
1679 else
1680 fprintf (f, "l%d", ALLOCNO_LOOP_TREE_NODE (a)->loop_num);
1681 fprintf (f, ") costs:");
1682 for (k = 0; k < cost_classes_ptr->num; k++)
1684 rclass = cost_classes[k];
1685 fprintf (f, " %s:%d", reg_class_names[rclass],
1686 COSTS (costs, i)->cost[k]);
1687 if (flag_ira_region == IRA_REGION_ALL
1688 || flag_ira_region == IRA_REGION_MIXED)
1689 fprintf (f, ",%d", COSTS (total_allocno_costs, i)->cost[k]);
1691 fprintf (f, " MEM:%i", COSTS (costs, i)->mem_cost);
1692 if (flag_ira_region == IRA_REGION_ALL
1693 || flag_ira_region == IRA_REGION_MIXED)
1694 fprintf (f, ",%d", COSTS (total_allocno_costs, i)->mem_cost);
1695 fprintf (f, "\n");
1699 /* Print pseudo costs to file F. */
1700 static void
1701 print_pseudo_costs (FILE *f)
1703 int regno, k;
1704 int rclass;
1705 cost_classes_t cost_classes_ptr;
1706 enum reg_class *cost_classes;
1708 ira_assert (! allocno_p);
1709 fprintf (f, "\n");
1710 for (regno = max_reg_num () - 1; regno >= FIRST_PSEUDO_REGISTER; regno--)
1712 if (REG_N_REFS (regno) <= 0)
1713 continue;
1714 cost_classes_ptr = regno_cost_classes[regno];
1715 cost_classes = cost_classes_ptr->classes;
1716 fprintf (f, " r%d costs:", regno);
1717 for (k = 0; k < cost_classes_ptr->num; k++)
1719 rclass = cost_classes[k];
1720 fprintf (f, " %s:%d", reg_class_names[rclass],
1721 COSTS (costs, regno)->cost[k]);
1723 fprintf (f, " MEM:%i\n", COSTS (costs, regno)->mem_cost);
1727 /* Traverse the BB represented by LOOP_TREE_NODE to update the allocno
1728 costs. */
1729 static void
1730 process_bb_for_costs (basic_block bb)
1732 rtx_insn *insn;
1734 frequency = REG_FREQ_FROM_BB (bb);
1735 if (frequency == 0)
1736 frequency = 1;
1737 FOR_BB_INSNS (bb, insn)
1738 insn = scan_one_insn (insn);
1741 /* Traverse the BB represented by LOOP_TREE_NODE to update the allocno
1742 costs. */
1743 static void
1744 process_bb_node_for_costs (ira_loop_tree_node_t loop_tree_node)
1746 basic_block bb;
1748 bb = loop_tree_node->bb;
1749 if (bb != NULL)
1750 process_bb_for_costs (bb);
1753 /* Find costs of register classes and memory for allocnos or pseudos
1754 and their best costs. Set up preferred, alternative and allocno
1755 classes for pseudos. */
1756 static void
1757 find_costs_and_classes (FILE *dump_file)
1759 int i, k, start, max_cost_classes_num;
1760 int pass;
1761 basic_block bb;
1762 enum reg_class *regno_best_class, new_class;
1764 init_recog ();
1765 regno_best_class
1766 = (enum reg_class *) ira_allocate (max_reg_num ()
1767 * sizeof (enum reg_class));
1768 for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--)
1769 regno_best_class[i] = NO_REGS;
1770 if (!resize_reg_info () && allocno_p
1771 && pseudo_classes_defined_p && flag_expensive_optimizations)
1773 ira_allocno_t a;
1774 ira_allocno_iterator ai;
1776 pref = pref_buffer;
1777 max_cost_classes_num = 1;
1778 FOR_EACH_ALLOCNO (a, ai)
1780 pref[ALLOCNO_NUM (a)] = reg_preferred_class (ALLOCNO_REGNO (a));
1781 setup_regno_cost_classes_by_aclass
1782 (ALLOCNO_REGNO (a), pref[ALLOCNO_NUM (a)]);
1783 max_cost_classes_num
1784 = MAX (max_cost_classes_num,
1785 regno_cost_classes[ALLOCNO_REGNO (a)]->num);
1787 start = 1;
1789 else
1791 pref = NULL;
1792 max_cost_classes_num = ira_important_classes_num;
1793 for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--)
1794 if (regno_reg_rtx[i] != NULL_RTX)
1795 setup_regno_cost_classes_by_mode (i, PSEUDO_REGNO_MODE (i));
1796 else
1797 setup_regno_cost_classes_by_aclass (i, ALL_REGS);
1798 start = 0;
1800 if (allocno_p)
1801 /* Clear the flag for the next compiled function. */
1802 pseudo_classes_defined_p = false;
1803 /* Normally we scan the insns once and determine the best class to
1804 use for each allocno. However, if -fexpensive-optimizations are
1805 on, we do so twice, the second time using the tentative best
1806 classes to guide the selection. */
1807 for (pass = start; pass <= flag_expensive_optimizations; pass++)
1809 if ((!allocno_p || internal_flag_ira_verbose > 0) && dump_file)
1810 fprintf (dump_file,
1811 "\nPass %i for finding pseudo/allocno costs\n\n", pass);
1813 if (pass != start)
1815 max_cost_classes_num = 1;
1816 for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--)
1818 setup_regno_cost_classes_by_aclass (i, regno_best_class[i]);
1819 max_cost_classes_num
1820 = MAX (max_cost_classes_num, regno_cost_classes[i]->num);
1824 struct_costs_size
1825 = sizeof (struct costs) + sizeof (int) * (max_cost_classes_num - 1);
1826 /* Zero out our accumulation of the cost of each class for each
1827 allocno. */
1828 memset (costs, 0, cost_elements_num * struct_costs_size);
1830 if (allocno_p)
1832 /* Scan the instructions and record each time it would save code
1833 to put a certain allocno in a certain class. */
1834 ira_traverse_loop_tree (true, ira_loop_tree_root,
1835 process_bb_node_for_costs, NULL);
1837 memcpy (total_allocno_costs, costs,
1838 max_struct_costs_size * ira_allocnos_num);
1840 else
1842 basic_block bb;
1844 FOR_EACH_BB_FN (bb, cfun)
1845 process_bb_for_costs (bb);
1848 if (pass == 0)
1849 pref = pref_buffer;
1851 /* Now for each allocno look at how desirable each class is and
1852 find which class is preferred. */
1853 for (i = max_reg_num () - 1; i >= FIRST_PSEUDO_REGISTER; i--)
1855 ira_allocno_t a, parent_a;
1856 int rclass, a_num, parent_a_num, add_cost;
1857 ira_loop_tree_node_t parent;
1858 int best_cost, allocno_cost;
1859 enum reg_class best, alt_class;
1860 cost_classes_t cost_classes_ptr = regno_cost_classes[i];
1861 enum reg_class *cost_classes;
1862 int *i_costs = temp_costs->cost;
1863 int i_mem_cost;
1864 int equiv_savings = regno_equiv_gains[i];
1866 if (! allocno_p)
1868 if (regno_reg_rtx[i] == NULL_RTX)
1869 continue;
1870 memcpy (temp_costs, COSTS (costs, i), struct_costs_size);
1871 i_mem_cost = temp_costs->mem_cost;
1872 cost_classes = cost_classes_ptr->classes;
1874 else
1876 if (ira_regno_allocno_map[i] == NULL)
1877 continue;
1878 memset (temp_costs, 0, struct_costs_size);
1879 i_mem_cost = 0;
1880 cost_classes = cost_classes_ptr->classes;
1881 /* Find cost of all allocnos with the same regno. */
1882 for (a = ira_regno_allocno_map[i];
1883 a != NULL;
1884 a = ALLOCNO_NEXT_REGNO_ALLOCNO (a))
1886 int *a_costs, *p_costs;
1888 a_num = ALLOCNO_NUM (a);
1889 if ((flag_ira_region == IRA_REGION_ALL
1890 || flag_ira_region == IRA_REGION_MIXED)
1891 && (parent = ALLOCNO_LOOP_TREE_NODE (a)->parent) != NULL
1892 && (parent_a = parent->regno_allocno_map[i]) != NULL
1893 /* There are no caps yet. */
1894 && bitmap_bit_p (ALLOCNO_LOOP_TREE_NODE
1895 (a)->border_allocnos,
1896 ALLOCNO_NUM (a)))
1898 /* Propagate costs to upper levels in the region
1899 tree. */
1900 parent_a_num = ALLOCNO_NUM (parent_a);
1901 a_costs = COSTS (total_allocno_costs, a_num)->cost;
1902 p_costs = COSTS (total_allocno_costs, parent_a_num)->cost;
1903 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
1905 add_cost = a_costs[k];
1906 if (add_cost > 0 && INT_MAX - add_cost < p_costs[k])
1907 p_costs[k] = INT_MAX;
1908 else
1909 p_costs[k] += add_cost;
1911 add_cost = COSTS (total_allocno_costs, a_num)->mem_cost;
1912 if (add_cost > 0
1913 && (INT_MAX - add_cost
1914 < COSTS (total_allocno_costs,
1915 parent_a_num)->mem_cost))
1916 COSTS (total_allocno_costs, parent_a_num)->mem_cost
1917 = INT_MAX;
1918 else
1919 COSTS (total_allocno_costs, parent_a_num)->mem_cost
1920 += add_cost;
1922 if (i >= first_moveable_pseudo && i < last_moveable_pseudo)
1923 COSTS (total_allocno_costs, parent_a_num)->mem_cost = 0;
1925 a_costs = COSTS (costs, a_num)->cost;
1926 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
1928 add_cost = a_costs[k];
1929 if (add_cost > 0 && INT_MAX - add_cost < i_costs[k])
1930 i_costs[k] = INT_MAX;
1931 else
1932 i_costs[k] += add_cost;
1934 add_cost = COSTS (costs, a_num)->mem_cost;
1935 if (add_cost > 0 && INT_MAX - add_cost < i_mem_cost)
1936 i_mem_cost = INT_MAX;
1937 else
1938 i_mem_cost += add_cost;
1941 if (i >= first_moveable_pseudo && i < last_moveable_pseudo)
1942 i_mem_cost = 0;
1943 else if (equiv_savings < 0)
1944 i_mem_cost = -equiv_savings;
1945 else if (equiv_savings > 0)
1947 i_mem_cost = 0;
1948 for (k = cost_classes_ptr->num - 1; k >= 0; k--)
1949 i_costs[k] += equiv_savings;
1952 best_cost = (1 << (HOST_BITS_PER_INT - 2)) - 1;
1953 best = ALL_REGS;
1954 alt_class = NO_REGS;
1955 /* Find best common class for all allocnos with the same
1956 regno. */
1957 for (k = 0; k < cost_classes_ptr->num; k++)
1959 rclass = cost_classes[k];
1960 if (i_costs[k] < best_cost)
1962 best_cost = i_costs[k];
1963 best = (enum reg_class) rclass;
1965 else if (i_costs[k] == best_cost)
1966 best = ira_reg_class_subunion[best][rclass];
1967 if (pass == flag_expensive_optimizations
1968 /* We still prefer registers to memory even at this
1969 stage if their costs are the same. We will make
1970 a final decision during assigning hard registers
1971 when we have all info including more accurate
1972 costs which might be affected by assigning hard
1973 registers to other pseudos because the pseudos
1974 involved in moves can be coalesced. */
1975 && i_costs[k] <= i_mem_cost
1976 && (reg_class_size[reg_class_subunion[alt_class][rclass]]
1977 > reg_class_size[alt_class]))
1978 alt_class = reg_class_subunion[alt_class][rclass];
1980 alt_class = ira_allocno_class_translate[alt_class];
1981 if (best_cost > i_mem_cost
1982 && ! non_spilled_static_chain_regno_p (i))
1983 regno_aclass[i] = NO_REGS;
1984 else if (!optimize && !targetm.class_likely_spilled_p (best))
1985 /* Registers in the alternative class are likely to need
1986 longer or slower sequences than registers in the best class.
1987 When optimizing we make some effort to use the best class
1988 over the alternative class where possible, but at -O0 we
1989 effectively give the alternative class equal weight.
1990 We then run the risk of using slower alternative registers
1991 when plenty of registers from the best class are still free.
1992 This is especially true because live ranges tend to be very
1993 short in -O0 code and so register pressure tends to be low.
1995 Avoid that by ignoring the alternative class if the best
1996 class has plenty of registers.
1998 The union class arrays give important classes and only
1999 part of it are allocno classes. So translate them into
2000 allocno classes. */
2001 regno_aclass[i] = ira_allocno_class_translate[best];
2002 else
2004 /* Make the common class the biggest class of best and
2005 alt_class. Translate the common class into an
2006 allocno class too. */
2007 regno_aclass[i] = (ira_allocno_class_translate
2008 [ira_reg_class_superunion[best][alt_class]]);
2009 ira_assert (regno_aclass[i] != NO_REGS
2010 && ira_reg_allocno_class_p[regno_aclass[i]]);
2012 if ((new_class
2013 = (reg_class) (targetm.ira_change_pseudo_allocno_class
2014 (i, regno_aclass[i], best))) != regno_aclass[i])
2016 regno_aclass[i] = new_class;
2017 if (hard_reg_set_subset_p (reg_class_contents[new_class],
2018 reg_class_contents[best]))
2019 best = new_class;
2020 if (hard_reg_set_subset_p (reg_class_contents[new_class],
2021 reg_class_contents[alt_class]))
2022 alt_class = new_class;
2024 if (pass == flag_expensive_optimizations)
2026 if (best_cost > i_mem_cost
2027 /* Do not assign NO_REGS to static chain pointer
2028 pseudo when non-local goto is used. */
2029 && ! non_spilled_static_chain_regno_p (i))
2030 best = alt_class = NO_REGS;
2031 else if (best == alt_class)
2032 alt_class = NO_REGS;
2033 setup_reg_classes (i, best, alt_class, regno_aclass[i]);
2034 if ((!allocno_p || internal_flag_ira_verbose > 2)
2035 && dump_file != NULL)
2036 fprintf (dump_file,
2037 " r%d: preferred %s, alternative %s, allocno %s\n",
2038 i, reg_class_names[best], reg_class_names[alt_class],
2039 reg_class_names[regno_aclass[i]]);
2041 regno_best_class[i] = best;
2042 if (! allocno_p)
2044 pref[i] = (best_cost > i_mem_cost
2045 && ! non_spilled_static_chain_regno_p (i)
2046 ? NO_REGS : best);
2047 continue;
2049 for (a = ira_regno_allocno_map[i];
2050 a != NULL;
2051 a = ALLOCNO_NEXT_REGNO_ALLOCNO (a))
2053 enum reg_class aclass = regno_aclass[i];
2054 int a_num = ALLOCNO_NUM (a);
2055 int *total_a_costs = COSTS (total_allocno_costs, a_num)->cost;
2056 int *a_costs = COSTS (costs, a_num)->cost;
2058 if (aclass == NO_REGS)
2059 best = NO_REGS;
2060 else
2062 /* Finding best class which is subset of the common
2063 class. */
2064 best_cost = (1 << (HOST_BITS_PER_INT - 2)) - 1;
2065 allocno_cost = best_cost;
2066 best = ALL_REGS;
2067 for (k = 0; k < cost_classes_ptr->num; k++)
2069 rclass = cost_classes[k];
2070 if (! ira_class_subset_p[rclass][aclass])
2071 continue;
2072 if (total_a_costs[k] < best_cost)
2074 best_cost = total_a_costs[k];
2075 allocno_cost = a_costs[k];
2076 best = (enum reg_class) rclass;
2078 else if (total_a_costs[k] == best_cost)
2080 best = ira_reg_class_subunion[best][rclass];
2081 allocno_cost = MAX (allocno_cost, a_costs[k]);
2084 ALLOCNO_CLASS_COST (a) = allocno_cost;
2086 if (internal_flag_ira_verbose > 2 && dump_file != NULL
2087 && (pass == 0 || pref[a_num] != best))
2089 fprintf (dump_file, " a%d (r%d,", a_num, i);
2090 if ((bb = ALLOCNO_LOOP_TREE_NODE (a)->bb) != NULL)
2091 fprintf (dump_file, "b%d", bb->index);
2092 else
2093 fprintf (dump_file, "l%d",
2094 ALLOCNO_LOOP_TREE_NODE (a)->loop_num);
2095 fprintf (dump_file, ") best %s, allocno %s\n",
2096 reg_class_names[best],
2097 reg_class_names[aclass]);
2099 pref[a_num] = best;
2100 if (pass == flag_expensive_optimizations && best != aclass
2101 && ira_class_hard_regs_num[best] > 0
2102 && (ira_reg_class_max_nregs[best][ALLOCNO_MODE (a)]
2103 >= ira_class_hard_regs_num[best]))
2105 int ind = cost_classes_ptr->index[aclass];
2107 ira_assert (ind >= 0);
2108 ira_init_register_move_cost_if_necessary (ALLOCNO_MODE (a));
2109 ira_add_allocno_pref (a, ira_class_hard_regs[best][0],
2110 (a_costs[ind] - ALLOCNO_CLASS_COST (a))
2111 / (ira_register_move_cost
2112 [ALLOCNO_MODE (a)][best][aclass]));
2113 for (k = 0; k < cost_classes_ptr->num; k++)
2114 if (ira_class_subset_p[cost_classes[k]][best])
2115 a_costs[k] = a_costs[ind];
2120 if (internal_flag_ira_verbose > 4 && dump_file)
2122 if (allocno_p)
2123 print_allocno_costs (dump_file);
2124 else
2125 print_pseudo_costs (dump_file);
2126 fprintf (dump_file,"\n");
2129 ira_free (regno_best_class);
2134 /* Process moves involving hard regs to modify allocno hard register
2135 costs. We can do this only after determining allocno class. If a
2136 hard register forms a register class, then moves with the hard
2137 register are already taken into account in class costs for the
2138 allocno. */
2139 static void
2140 process_bb_node_for_hard_reg_moves (ira_loop_tree_node_t loop_tree_node)
2142 int i, freq, src_regno, dst_regno, hard_regno, a_regno;
2143 bool to_p;
2144 ira_allocno_t a, curr_a;
2145 ira_loop_tree_node_t curr_loop_tree_node;
2146 enum reg_class rclass;
2147 basic_block bb;
2148 rtx_insn *insn;
2149 rtx set, src, dst;
2151 bb = loop_tree_node->bb;
2152 if (bb == NULL)
2153 return;
2154 freq = REG_FREQ_FROM_BB (bb);
2155 if (freq == 0)
2156 freq = 1;
2157 FOR_BB_INSNS (bb, insn)
2159 if (!NONDEBUG_INSN_P (insn))
2160 continue;
2161 set = single_set (insn);
2162 if (set == NULL_RTX)
2163 continue;
2164 dst = SET_DEST (set);
2165 src = SET_SRC (set);
2166 if (! REG_P (dst) || ! REG_P (src))
2167 continue;
2168 dst_regno = REGNO (dst);
2169 src_regno = REGNO (src);
2170 if (dst_regno >= FIRST_PSEUDO_REGISTER
2171 && src_regno < FIRST_PSEUDO_REGISTER)
2173 hard_regno = src_regno;
2174 a = ira_curr_regno_allocno_map[dst_regno];
2175 to_p = true;
2177 else if (src_regno >= FIRST_PSEUDO_REGISTER
2178 && dst_regno < FIRST_PSEUDO_REGISTER)
2180 hard_regno = dst_regno;
2181 a = ira_curr_regno_allocno_map[src_regno];
2182 to_p = false;
2184 else
2185 continue;
2186 if (reg_class_size[(int) REGNO_REG_CLASS (hard_regno)]
2187 == (ira_reg_class_max_nregs
2188 [REGNO_REG_CLASS (hard_regno)][(int) ALLOCNO_MODE(a)]))
2189 /* If the class can provide only one hard reg to the allocno,
2190 we processed the insn record_operand_costs already and we
2191 actually updated the hard reg cost there. */
2192 continue;
2193 rclass = ALLOCNO_CLASS (a);
2194 if (! TEST_HARD_REG_BIT (reg_class_contents[rclass], hard_regno))
2195 continue;
2196 i = ira_class_hard_reg_index[rclass][hard_regno];
2197 if (i < 0)
2198 continue;
2199 a_regno = ALLOCNO_REGNO (a);
2200 for (curr_loop_tree_node = ALLOCNO_LOOP_TREE_NODE (a);
2201 curr_loop_tree_node != NULL;
2202 curr_loop_tree_node = curr_loop_tree_node->parent)
2203 if ((curr_a = curr_loop_tree_node->regno_allocno_map[a_regno]) != NULL)
2204 ira_add_allocno_pref (curr_a, hard_regno, freq);
2206 int cost;
2207 enum reg_class hard_reg_class;
2208 machine_mode mode;
2210 mode = ALLOCNO_MODE (a);
2211 hard_reg_class = REGNO_REG_CLASS (hard_regno);
2212 ira_init_register_move_cost_if_necessary (mode);
2213 cost = (to_p ? ira_register_move_cost[mode][hard_reg_class][rclass]
2214 : ira_register_move_cost[mode][rclass][hard_reg_class]) * freq;
2215 ira_allocate_and_set_costs (&ALLOCNO_HARD_REG_COSTS (a), rclass,
2216 ALLOCNO_CLASS_COST (a));
2217 ira_allocate_and_set_costs (&ALLOCNO_CONFLICT_HARD_REG_COSTS (a),
2218 rclass, 0);
2219 ALLOCNO_HARD_REG_COSTS (a)[i] -= cost;
2220 ALLOCNO_CONFLICT_HARD_REG_COSTS (a)[i] -= cost;
2221 ALLOCNO_CLASS_COST (a) = MIN (ALLOCNO_CLASS_COST (a),
2222 ALLOCNO_HARD_REG_COSTS (a)[i]);
2227 /* After we find hard register and memory costs for allocnos, define
2228 its class and modify hard register cost because insns moving
2229 allocno to/from hard registers. */
2230 static void
2231 setup_allocno_class_and_costs (void)
2233 int i, j, n, regno, hard_regno, num;
2234 int *reg_costs;
2235 enum reg_class aclass, rclass;
2236 ira_allocno_t a;
2237 ira_allocno_iterator ai;
2238 cost_classes_t cost_classes_ptr;
2240 ira_assert (allocno_p);
2241 FOR_EACH_ALLOCNO (a, ai)
2243 i = ALLOCNO_NUM (a);
2244 regno = ALLOCNO_REGNO (a);
2245 aclass = regno_aclass[regno];
2246 cost_classes_ptr = regno_cost_classes[regno];
2247 ira_assert (pref[i] == NO_REGS || aclass != NO_REGS);
2248 ALLOCNO_MEMORY_COST (a) = COSTS (costs, i)->mem_cost;
2249 ira_set_allocno_class (a, aclass);
2250 if (aclass == NO_REGS)
2251 continue;
2252 if (optimize && ALLOCNO_CLASS (a) != pref[i])
2254 n = ira_class_hard_regs_num[aclass];
2255 ALLOCNO_HARD_REG_COSTS (a)
2256 = reg_costs = ira_allocate_cost_vector (aclass);
2257 for (j = n - 1; j >= 0; j--)
2259 hard_regno = ira_class_hard_regs[aclass][j];
2260 if (TEST_HARD_REG_BIT (reg_class_contents[pref[i]], hard_regno))
2261 reg_costs[j] = ALLOCNO_CLASS_COST (a);
2262 else
2264 rclass = REGNO_REG_CLASS (hard_regno);
2265 num = cost_classes_ptr->index[rclass];
2266 if (num < 0)
2268 num = cost_classes_ptr->hard_regno_index[hard_regno];
2269 ira_assert (num >= 0);
2271 reg_costs[j] = COSTS (costs, i)->cost[num];
2276 if (optimize)
2277 ira_traverse_loop_tree (true, ira_loop_tree_root,
2278 process_bb_node_for_hard_reg_moves, NULL);
2283 /* Function called once during compiler work. */
2284 void
2285 ira_init_costs_once (void)
2287 int i;
2289 init_cost = NULL;
2290 for (i = 0; i < MAX_RECOG_OPERANDS; i++)
2292 op_costs[i] = NULL;
2293 this_op_costs[i] = NULL;
2295 temp_costs = NULL;
2298 /* Free allocated temporary cost vectors. */
2299 void
2300 target_ira_int::free_ira_costs ()
2302 int i;
2304 free (x_init_cost);
2305 x_init_cost = NULL;
2306 for (i = 0; i < MAX_RECOG_OPERANDS; i++)
2308 free (x_op_costs[i]);
2309 free (x_this_op_costs[i]);
2310 x_op_costs[i] = x_this_op_costs[i] = NULL;
2312 free (x_temp_costs);
2313 x_temp_costs = NULL;
2316 /* This is called each time register related information is
2317 changed. */
2318 void
2319 ira_init_costs (void)
2321 int i;
2323 this_target_ira_int->free_ira_costs ();
2324 max_struct_costs_size
2325 = sizeof (struct costs) + sizeof (int) * (ira_important_classes_num - 1);
2326 /* Don't use ira_allocate because vectors live through several IRA
2327 calls. */
2328 init_cost = (struct costs *) xmalloc (max_struct_costs_size);
2329 init_cost->mem_cost = 1000000;
2330 for (i = 0; i < ira_important_classes_num; i++)
2331 init_cost->cost[i] = 1000000;
2332 for (i = 0; i < MAX_RECOG_OPERANDS; i++)
2334 op_costs[i] = (struct costs *) xmalloc (max_struct_costs_size);
2335 this_op_costs[i] = (struct costs *) xmalloc (max_struct_costs_size);
2337 temp_costs = (struct costs *) xmalloc (max_struct_costs_size);
2342 /* Common initialization function for ira_costs and
2343 ira_set_pseudo_classes. */
2344 static void
2345 init_costs (void)
2347 init_subregs_of_mode ();
2348 costs = (struct costs *) ira_allocate (max_struct_costs_size
2349 * cost_elements_num);
2350 pref_buffer = (enum reg_class *) ira_allocate (sizeof (enum reg_class)
2351 * cost_elements_num);
2352 regno_aclass = (enum reg_class *) ira_allocate (sizeof (enum reg_class)
2353 * max_reg_num ());
2354 regno_equiv_gains = (int *) ira_allocate (sizeof (int) * max_reg_num ());
2355 memset (regno_equiv_gains, 0, sizeof (int) * max_reg_num ());
2358 /* Common finalization function for ira_costs and
2359 ira_set_pseudo_classes. */
2360 static void
2361 finish_costs (void)
2363 finish_subregs_of_mode ();
2364 ira_free (regno_equiv_gains);
2365 ira_free (regno_aclass);
2366 ira_free (pref_buffer);
2367 ira_free (costs);
2370 /* Entry function which defines register class, memory and hard
2371 register costs for each allocno. */
2372 void
2373 ira_costs (void)
2375 allocno_p = true;
2376 cost_elements_num = ira_allocnos_num;
2377 init_costs ();
2378 total_allocno_costs = (struct costs *) ira_allocate (max_struct_costs_size
2379 * ira_allocnos_num);
2380 initiate_regno_cost_classes ();
2381 calculate_elim_costs_all_insns ();
2382 find_costs_and_classes (ira_dump_file);
2383 setup_allocno_class_and_costs ();
2384 finish_regno_cost_classes ();
2385 finish_costs ();
2386 ira_free (total_allocno_costs);
2389 /* Entry function which defines classes for pseudos.
2390 Set pseudo_classes_defined_p only if DEFINE_PSEUDO_CLASSES is true. */
2391 void
2392 ira_set_pseudo_classes (bool define_pseudo_classes, FILE *dump_file)
2394 allocno_p = false;
2395 internal_flag_ira_verbose = flag_ira_verbose;
2396 cost_elements_num = max_reg_num ();
2397 init_costs ();
2398 initiate_regno_cost_classes ();
2399 find_costs_and_classes (dump_file);
2400 finish_regno_cost_classes ();
2401 if (define_pseudo_classes)
2402 pseudo_classes_defined_p = true;
2404 finish_costs ();
2409 /* Change hard register costs for allocnos which lives through
2410 function calls. This is called only when we found all intersected
2411 calls during building allocno live ranges. */
2412 void
2413 ira_tune_allocno_costs (void)
2415 int j, n, regno;
2416 int cost, min_cost, *reg_costs;
2417 enum reg_class aclass;
2418 machine_mode mode;
2419 ira_allocno_t a;
2420 ira_allocno_iterator ai;
2421 ira_allocno_object_iterator oi;
2422 ira_object_t obj;
2423 bool skip_p;
2425 FOR_EACH_ALLOCNO (a, ai)
2427 aclass = ALLOCNO_CLASS (a);
2428 if (aclass == NO_REGS)
2429 continue;
2430 mode = ALLOCNO_MODE (a);
2431 n = ira_class_hard_regs_num[aclass];
2432 min_cost = INT_MAX;
2433 if (ALLOCNO_CALLS_CROSSED_NUM (a)
2434 != ALLOCNO_CHEAP_CALLS_CROSSED_NUM (a))
2436 ira_allocate_and_set_costs
2437 (&ALLOCNO_HARD_REG_COSTS (a), aclass,
2438 ALLOCNO_CLASS_COST (a));
2439 reg_costs = ALLOCNO_HARD_REG_COSTS (a);
2440 for (j = n - 1; j >= 0; j--)
2442 regno = ira_class_hard_regs[aclass][j];
2443 skip_p = false;
2444 FOR_EACH_ALLOCNO_OBJECT (a, obj, oi)
2446 if (ira_hard_reg_set_intersection_p (regno, mode,
2447 OBJECT_CONFLICT_HARD_REGS
2448 (obj)))
2450 skip_p = true;
2451 break;
2454 if (skip_p)
2455 continue;
2456 cost = 0;
2457 if (ira_need_caller_save_p (a, regno))
2458 cost += ira_caller_save_cost (a);
2459 #ifdef IRA_HARD_REGNO_ADD_COST_MULTIPLIER
2461 auto rclass = REGNO_REG_CLASS (regno);
2462 cost += ((ira_memory_move_cost[mode][rclass][0]
2463 + ira_memory_move_cost[mode][rclass][1])
2464 * ALLOCNO_FREQ (a)
2465 * IRA_HARD_REGNO_ADD_COST_MULTIPLIER (regno) / 2);
2467 #endif
2468 if (INT_MAX - cost < reg_costs[j])
2469 reg_costs[j] = INT_MAX;
2470 else
2471 reg_costs[j] += cost;
2472 if (min_cost > reg_costs[j])
2473 min_cost = reg_costs[j];
2476 if (min_cost != INT_MAX)
2477 ALLOCNO_CLASS_COST (a) = min_cost;
2479 /* Some targets allow pseudos to be allocated to unaligned sequences
2480 of hard registers. However, selecting an unaligned sequence can
2481 unnecessarily restrict later allocations. So increase the cost of
2482 unaligned hard regs to encourage the use of aligned hard regs. */
2484 const int nregs = ira_reg_class_max_nregs[aclass][ALLOCNO_MODE (a)];
2486 if (nregs > 1)
2488 ira_allocate_and_set_costs
2489 (&ALLOCNO_HARD_REG_COSTS (a), aclass, ALLOCNO_CLASS_COST (a));
2490 reg_costs = ALLOCNO_HARD_REG_COSTS (a);
2491 for (j = n - 1; j >= 0; j--)
2493 regno = ira_non_ordered_class_hard_regs[aclass][j];
2494 if ((regno % nregs) != 0)
2496 int index = ira_class_hard_reg_index[aclass][regno];
2497 ira_assert (index != -1);
2498 reg_costs[index] += ALLOCNO_FREQ (a);
2506 /* Add COST to the estimated gain for eliminating REGNO with its
2507 equivalence. If COST is zero, record that no such elimination is
2508 possible. */
2510 void
2511 ira_adjust_equiv_reg_cost (unsigned regno, int cost)
2513 if (cost == 0)
2514 regno_equiv_gains[regno] = 0;
2515 else
2516 regno_equiv_gains[regno] += cost;
2519 void
2520 ira_costs_cc_finalize (void)
2522 this_target_ira_int->free_ira_costs ();