2015-01-20 Jeff Law <law@redhat.com>
[official-gcc.git] / gcc / lra-constraints.c
blob6e4be72fedd953ab10055cb944a4c7a48305a2c1
1 /* Code for RTL transformations to satisfy insn constraints.
2 Copyright (C) 2010-2015 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/>. */
22 /* This file contains code for 3 passes: constraint pass,
23 inheritance/split pass, and pass for undoing failed inheritance and
24 split.
26 The major goal of constraint pass is to transform RTL to satisfy
27 insn and address constraints by:
28 o choosing insn alternatives;
29 o generating *reload insns* (or reloads in brief) and *reload
30 pseudos* which will get necessary hard registers later;
31 o substituting pseudos with equivalent values and removing the
32 instructions that initialized those pseudos.
34 The constraint pass has biggest and most complicated code in LRA.
35 There are a lot of important details like:
36 o reuse of input reload pseudos to simplify reload pseudo
37 allocations;
38 o some heuristics to choose insn alternative to improve the
39 inheritance;
40 o early clobbers etc.
42 The pass is mimicking former reload pass in alternative choosing
43 because the reload pass is oriented to current machine description
44 model. It might be changed if the machine description model is
45 changed.
47 There is special code for preventing all LRA and this pass cycling
48 in case of bugs.
50 On the first iteration of the pass we process every instruction and
51 choose an alternative for each one. On subsequent iterations we try
52 to avoid reprocessing instructions if we can be sure that the old
53 choice is still valid.
55 The inheritance/spilt pass is to transform code to achieve
56 ineheritance and live range splitting. It is done on backward
57 traversal of EBBs.
59 The inheritance optimization goal is to reuse values in hard
60 registers. There is analogous optimization in old reload pass. The
61 inheritance is achieved by following transformation:
63 reload_p1 <- p reload_p1 <- p
64 ... new_p <- reload_p1
65 ... => ...
66 reload_p2 <- p reload_p2 <- new_p
68 where p is spilled and not changed between the insns. Reload_p1 is
69 also called *original pseudo* and new_p is called *inheritance
70 pseudo*.
72 The subsequent assignment pass will try to assign the same (or
73 another if it is not possible) hard register to new_p as to
74 reload_p1 or reload_p2.
76 If the assignment pass fails to assign a hard register to new_p,
77 this file will undo the inheritance and restore the original code.
78 This is because implementing the above sequence with a spilled
79 new_p would make the code much worse. The inheritance is done in
80 EBB scope. The above is just a simplified example to get an idea
81 of the inheritance as the inheritance is also done for non-reload
82 insns.
84 Splitting (transformation) is also done in EBB scope on the same
85 pass as the inheritance:
87 r <- ... or ... <- r r <- ... or ... <- r
88 ... s <- r (new insn -- save)
89 ... =>
90 ... r <- s (new insn -- restore)
91 ... <- r ... <- r
93 The *split pseudo* s is assigned to the hard register of the
94 original pseudo or hard register r.
96 Splitting is done:
97 o In EBBs with high register pressure for global pseudos (living
98 in at least 2 BBs) and assigned to hard registers when there
99 are more one reloads needing the hard registers;
100 o for pseudos needing save/restore code around calls.
102 If the split pseudo still has the same hard register as the
103 original pseudo after the subsequent assignment pass or the
104 original pseudo was split, the opposite transformation is done on
105 the same pass for undoing inheritance. */
107 #undef REG_OK_STRICT
109 #include "config.h"
110 #include "system.h"
111 #include "coretypes.h"
112 #include "tm.h"
113 #include "hard-reg-set.h"
114 #include "rtl.h"
115 #include "tm_p.h"
116 #include "regs.h"
117 #include "insn-config.h"
118 #include "insn-codes.h"
119 #include "recog.h"
120 #include "output.h"
121 #include "addresses.h"
122 #include "target.h"
123 #include "hashtab.h"
124 #include "hash-set.h"
125 #include "vec.h"
126 #include "machmode.h"
127 #include "input.h"
128 #include "function.h"
129 #include "symtab.h"
130 #include "flags.h"
131 #include "statistics.h"
132 #include "double-int.h"
133 #include "real.h"
134 #include "fixed-value.h"
135 #include "alias.h"
136 #include "wide-int.h"
137 #include "inchash.h"
138 #include "tree.h"
139 #include "expmed.h"
140 #include "dojump.h"
141 #include "explow.h"
142 #include "calls.h"
143 #include "emit-rtl.h"
144 #include "varasm.h"
145 #include "stmt.h"
146 #include "expr.h"
147 #include "predict.h"
148 #include "dominance.h"
149 #include "cfg.h"
150 #include "cfgrtl.h"
151 #include "basic-block.h"
152 #include "except.h"
153 #include "optabs.h"
154 #include "df.h"
155 #include "ira.h"
156 #include "rtl-error.h"
157 #include "lra-int.h"
159 /* Value of LRA_CURR_RELOAD_NUM at the beginning of BB of the current
160 insn. Remember that LRA_CURR_RELOAD_NUM is the number of emitted
161 reload insns. */
162 static int bb_reload_num;
164 /* The current insn being processed and corresponding its single set
165 (NULL otherwise), its data (basic block, the insn data, the insn
166 static data, and the mode of each operand). */
167 static rtx_insn *curr_insn;
168 static rtx curr_insn_set;
169 static basic_block curr_bb;
170 static lra_insn_recog_data_t curr_id;
171 static struct lra_static_insn_data *curr_static_id;
172 static machine_mode curr_operand_mode[MAX_RECOG_OPERANDS];
176 /* Start numbers for new registers and insns at the current constraints
177 pass start. */
178 static int new_regno_start;
179 static int new_insn_uid_start;
181 /* If LOC is nonnull, strip any outer subreg from it. */
182 static inline rtx *
183 strip_subreg (rtx *loc)
185 return loc && GET_CODE (*loc) == SUBREG ? &SUBREG_REG (*loc) : loc;
188 /* Return hard regno of REGNO or if it is was not assigned to a hard
189 register, use a hard register from its allocno class. */
190 static int
191 get_try_hard_regno (int regno)
193 int hard_regno;
194 enum reg_class rclass;
196 if ((hard_regno = regno) >= FIRST_PSEUDO_REGISTER)
197 hard_regno = lra_get_regno_hard_regno (regno);
198 if (hard_regno >= 0)
199 return hard_regno;
200 rclass = lra_get_allocno_class (regno);
201 if (rclass == NO_REGS)
202 return -1;
203 return ira_class_hard_regs[rclass][0];
206 /* Return final hard regno (plus offset) which will be after
207 elimination. We do this for matching constraints because the final
208 hard regno could have a different class. */
209 static int
210 get_final_hard_regno (int hard_regno, int offset)
212 if (hard_regno < 0)
213 return hard_regno;
214 hard_regno = lra_get_elimination_hard_regno (hard_regno);
215 return hard_regno + offset;
218 /* Return hard regno of X after removing subreg and making
219 elimination. If X is not a register or subreg of register, return
220 -1. For pseudo use its assignment. */
221 static int
222 get_hard_regno (rtx x)
224 rtx reg;
225 int offset, hard_regno;
227 reg = x;
228 if (GET_CODE (x) == SUBREG)
229 reg = SUBREG_REG (x);
230 if (! REG_P (reg))
231 return -1;
232 if ((hard_regno = REGNO (reg)) >= FIRST_PSEUDO_REGISTER)
233 hard_regno = lra_get_regno_hard_regno (hard_regno);
234 if (hard_regno < 0)
235 return -1;
236 offset = 0;
237 if (GET_CODE (x) == SUBREG)
238 offset += subreg_regno_offset (hard_regno, GET_MODE (reg),
239 SUBREG_BYTE (x), GET_MODE (x));
240 return get_final_hard_regno (hard_regno, offset);
243 /* If REGNO is a hard register or has been allocated a hard register,
244 return the class of that register. If REGNO is a reload pseudo
245 created by the current constraints pass, return its allocno class.
246 Return NO_REGS otherwise. */
247 static enum reg_class
248 get_reg_class (int regno)
250 int hard_regno;
252 if ((hard_regno = regno) >= FIRST_PSEUDO_REGISTER)
253 hard_regno = lra_get_regno_hard_regno (regno);
254 if (hard_regno >= 0)
256 hard_regno = get_final_hard_regno (hard_regno, 0);
257 return REGNO_REG_CLASS (hard_regno);
259 if (regno >= new_regno_start)
260 return lra_get_allocno_class (regno);
261 return NO_REGS;
264 /* Return true if REG satisfies (or will satisfy) reg class constraint
265 CL. Use elimination first if REG is a hard register. If REG is a
266 reload pseudo created by this constraints pass, assume that it will
267 be allocated a hard register from its allocno class, but allow that
268 class to be narrowed to CL if it is currently a superset of CL.
270 If NEW_CLASS is nonnull, set *NEW_CLASS to the new allocno class of
271 REGNO (reg), or NO_REGS if no change in its class was needed. */
272 static bool
273 in_class_p (rtx reg, enum reg_class cl, enum reg_class *new_class)
275 enum reg_class rclass, common_class;
276 machine_mode reg_mode;
277 int class_size, hard_regno, nregs, i, j;
278 int regno = REGNO (reg);
280 if (new_class != NULL)
281 *new_class = NO_REGS;
282 if (regno < FIRST_PSEUDO_REGISTER)
284 rtx final_reg = reg;
285 rtx *final_loc = &final_reg;
287 lra_eliminate_reg_if_possible (final_loc);
288 return TEST_HARD_REG_BIT (reg_class_contents[cl], REGNO (*final_loc));
290 reg_mode = GET_MODE (reg);
291 rclass = get_reg_class (regno);
292 if (regno < new_regno_start
293 /* Do not allow the constraints for reload instructions to
294 influence the classes of new pseudos. These reloads are
295 typically moves that have many alternatives, and restricting
296 reload pseudos for one alternative may lead to situations
297 where other reload pseudos are no longer allocatable. */
298 || (INSN_UID (curr_insn) >= new_insn_uid_start
299 && curr_insn_set != NULL
300 && ((OBJECT_P (SET_SRC (curr_insn_set))
301 && ! CONSTANT_P (SET_SRC (curr_insn_set)))
302 || (GET_CODE (SET_SRC (curr_insn_set)) == SUBREG
303 && OBJECT_P (SUBREG_REG (SET_SRC (curr_insn_set)))
304 && ! CONSTANT_P (SUBREG_REG (SET_SRC (curr_insn_set)))))))
305 /* When we don't know what class will be used finally for reload
306 pseudos, we use ALL_REGS. */
307 return ((regno >= new_regno_start && rclass == ALL_REGS)
308 || (rclass != NO_REGS && ira_class_subset_p[rclass][cl]
309 && ! hard_reg_set_subset_p (reg_class_contents[cl],
310 lra_no_alloc_regs)));
311 else
313 common_class = ira_reg_class_subset[rclass][cl];
314 if (new_class != NULL)
315 *new_class = common_class;
316 if (hard_reg_set_subset_p (reg_class_contents[common_class],
317 lra_no_alloc_regs))
318 return false;
319 /* Check that there are enough allocatable regs. */
320 class_size = ira_class_hard_regs_num[common_class];
321 for (i = 0; i < class_size; i++)
323 hard_regno = ira_class_hard_regs[common_class][i];
324 nregs = hard_regno_nregs[hard_regno][reg_mode];
325 if (nregs == 1)
326 return true;
327 for (j = 0; j < nregs; j++)
328 if (TEST_HARD_REG_BIT (lra_no_alloc_regs, hard_regno + j)
329 || ! TEST_HARD_REG_BIT (reg_class_contents[common_class],
330 hard_regno + j))
331 break;
332 if (j >= nregs)
333 return true;
335 return false;
339 /* Return true if REGNO satisfies a memory constraint. */
340 static bool
341 in_mem_p (int regno)
343 return get_reg_class (regno) == NO_REGS;
346 /* Return 1 if ADDR is a valid memory address for mode MODE in address
347 space AS, and check that each pseudo has the proper kind of hard
348 reg. */
349 static int
350 valid_address_p (machine_mode mode ATTRIBUTE_UNUSED,
351 rtx addr, addr_space_t as)
353 #ifdef GO_IF_LEGITIMATE_ADDRESS
354 lra_assert (ADDR_SPACE_GENERIC_P (as));
355 GO_IF_LEGITIMATE_ADDRESS (mode, addr, win);
356 return 0;
358 win:
359 return 1;
360 #else
361 return targetm.addr_space.legitimate_address_p (mode, addr, 0, as);
362 #endif
365 namespace {
366 /* Temporarily eliminates registers in an address (for the lifetime of
367 the object). */
368 class address_eliminator {
369 public:
370 address_eliminator (struct address_info *ad);
371 ~address_eliminator ();
373 private:
374 struct address_info *m_ad;
375 rtx *m_base_loc;
376 rtx m_base_reg;
377 rtx *m_index_loc;
378 rtx m_index_reg;
382 address_eliminator::address_eliminator (struct address_info *ad)
383 : m_ad (ad),
384 m_base_loc (strip_subreg (ad->base_term)),
385 m_base_reg (NULL_RTX),
386 m_index_loc (strip_subreg (ad->index_term)),
387 m_index_reg (NULL_RTX)
389 if (m_base_loc != NULL)
391 m_base_reg = *m_base_loc;
392 lra_eliminate_reg_if_possible (m_base_loc);
393 if (m_ad->base_term2 != NULL)
394 *m_ad->base_term2 = *m_ad->base_term;
396 if (m_index_loc != NULL)
398 m_index_reg = *m_index_loc;
399 lra_eliminate_reg_if_possible (m_index_loc);
403 address_eliminator::~address_eliminator ()
405 if (m_base_loc && *m_base_loc != m_base_reg)
407 *m_base_loc = m_base_reg;
408 if (m_ad->base_term2 != NULL)
409 *m_ad->base_term2 = *m_ad->base_term;
411 if (m_index_loc && *m_index_loc != m_index_reg)
412 *m_index_loc = m_index_reg;
415 /* Return true if the eliminated form of AD is a legitimate target address. */
416 static bool
417 valid_address_p (struct address_info *ad)
419 address_eliminator eliminator (ad);
420 return valid_address_p (ad->mode, *ad->outer, ad->as);
423 /* Return true if the eliminated form of memory reference OP satisfies
424 extra memory constraint CONSTRAINT. */
425 static bool
426 satisfies_memory_constraint_p (rtx op, enum constraint_num constraint)
428 struct address_info ad;
430 decompose_mem_address (&ad, op);
431 address_eliminator eliminator (&ad);
432 return constraint_satisfied_p (op, constraint);
435 /* Return true if the eliminated form of address AD satisfies extra
436 address constraint CONSTRAINT. */
437 static bool
438 satisfies_address_constraint_p (struct address_info *ad,
439 enum constraint_num constraint)
441 address_eliminator eliminator (ad);
442 return constraint_satisfied_p (*ad->outer, constraint);
445 /* Return true if the eliminated form of address OP satisfies extra
446 address constraint CONSTRAINT. */
447 static bool
448 satisfies_address_constraint_p (rtx op, enum constraint_num constraint)
450 struct address_info ad;
452 decompose_lea_address (&ad, &op);
453 return satisfies_address_constraint_p (&ad, constraint);
456 /* Initiate equivalences for LRA. As we keep original equivalences
457 before any elimination, we need to make copies otherwise any change
458 in insns might change the equivalences. */
459 void
460 lra_init_equiv (void)
462 ira_expand_reg_equiv ();
463 for (int i = FIRST_PSEUDO_REGISTER; i < max_reg_num (); i++)
465 rtx res;
467 if ((res = ira_reg_equiv[i].memory) != NULL_RTX)
468 ira_reg_equiv[i].memory = copy_rtx (res);
469 if ((res = ira_reg_equiv[i].invariant) != NULL_RTX)
470 ira_reg_equiv[i].invariant = copy_rtx (res);
474 static rtx loc_equivalence_callback (rtx, const_rtx, void *);
476 /* Update equivalence for REGNO. We need to this as the equivalence
477 might contain other pseudos which are changed by their
478 equivalences. */
479 static void
480 update_equiv (int regno)
482 rtx x;
484 if ((x = ira_reg_equiv[regno].memory) != NULL_RTX)
485 ira_reg_equiv[regno].memory
486 = simplify_replace_fn_rtx (x, NULL_RTX, loc_equivalence_callback,
487 NULL_RTX);
488 if ((x = ira_reg_equiv[regno].invariant) != NULL_RTX)
489 ira_reg_equiv[regno].invariant
490 = simplify_replace_fn_rtx (x, NULL_RTX, loc_equivalence_callback,
491 NULL_RTX);
494 /* If we have decided to substitute X with another value, return that
495 value, otherwise return X. */
496 static rtx
497 get_equiv (rtx x)
499 int regno;
500 rtx res;
502 if (! REG_P (x) || (regno = REGNO (x)) < FIRST_PSEUDO_REGISTER
503 || ! ira_reg_equiv[regno].defined_p
504 || ! ira_reg_equiv[regno].profitable_p
505 || lra_get_regno_hard_regno (regno) >= 0)
506 return x;
507 if ((res = ira_reg_equiv[regno].memory) != NULL_RTX)
509 if (targetm.cannot_substitute_mem_equiv_p (res))
510 return x;
511 return res;
513 if ((res = ira_reg_equiv[regno].constant) != NULL_RTX)
514 return res;
515 if ((res = ira_reg_equiv[regno].invariant) != NULL_RTX)
516 return res;
517 gcc_unreachable ();
520 /* If we have decided to substitute X with the equivalent value,
521 return that value after elimination for INSN, otherwise return
522 X. */
523 static rtx
524 get_equiv_with_elimination (rtx x, rtx_insn *insn)
526 rtx res = get_equiv (x);
528 if (x == res || CONSTANT_P (res))
529 return res;
530 return lra_eliminate_regs_1 (insn, res, GET_MODE (res),
531 0, false, false, true);
534 /* Set up curr_operand_mode. */
535 static void
536 init_curr_operand_mode (void)
538 int nop = curr_static_id->n_operands;
539 for (int i = 0; i < nop; i++)
541 machine_mode mode = GET_MODE (*curr_id->operand_loc[i]);
542 if (mode == VOIDmode)
544 /* The .md mode for address operands is the mode of the
545 addressed value rather than the mode of the address itself. */
546 if (curr_id->icode >= 0 && curr_static_id->operand[i].is_address)
547 mode = Pmode;
548 else
549 mode = curr_static_id->operand[i].mode;
551 curr_operand_mode[i] = mode;
557 /* The page contains code to reuse input reloads. */
559 /* Structure describes input reload of the current insns. */
560 struct input_reload
562 /* Reloaded value. */
563 rtx input;
564 /* Reload pseudo used. */
565 rtx reg;
568 /* The number of elements in the following array. */
569 static int curr_insn_input_reloads_num;
570 /* Array containing info about input reloads. It is used to find the
571 same input reload and reuse the reload pseudo in this case. */
572 static struct input_reload curr_insn_input_reloads[LRA_MAX_INSN_RELOADS];
574 /* Initiate data concerning reuse of input reloads for the current
575 insn. */
576 static void
577 init_curr_insn_input_reloads (void)
579 curr_insn_input_reloads_num = 0;
582 /* Create a new pseudo using MODE, RCLASS, ORIGINAL or reuse already
583 created input reload pseudo (only if TYPE is not OP_OUT). Don't
584 reuse pseudo if IN_SUBREG_P is true and the reused pseudo should be
585 wrapped up in SUBREG. The result pseudo is returned through
586 RESULT_REG. Return TRUE if we created a new pseudo, FALSE if we
587 reused the already created input reload pseudo. Use TITLE to
588 describe new registers for debug purposes. */
589 static bool
590 get_reload_reg (enum op_type type, machine_mode mode, rtx original,
591 enum reg_class rclass, bool in_subreg_p,
592 const char *title, rtx *result_reg)
594 int i, regno;
595 enum reg_class new_class;
597 if (type == OP_OUT)
599 *result_reg
600 = lra_create_new_reg_with_unique_value (mode, original, rclass, title);
601 return true;
603 /* Prevent reuse value of expression with side effects,
604 e.g. volatile memory. */
605 if (! side_effects_p (original))
606 for (i = 0; i < curr_insn_input_reloads_num; i++)
607 if (rtx_equal_p (curr_insn_input_reloads[i].input, original)
608 && in_class_p (curr_insn_input_reloads[i].reg, rclass, &new_class))
610 rtx reg = curr_insn_input_reloads[i].reg;
611 regno = REGNO (reg);
612 /* If input is equal to original and both are VOIDmode,
613 GET_MODE (reg) might be still different from mode.
614 Ensure we don't return *result_reg with wrong mode. */
615 if (GET_MODE (reg) != mode)
617 if (in_subreg_p)
618 continue;
619 if (GET_MODE_SIZE (GET_MODE (reg)) < GET_MODE_SIZE (mode))
620 continue;
621 reg = lowpart_subreg (mode, reg, GET_MODE (reg));
622 if (reg == NULL_RTX || GET_CODE (reg) != SUBREG)
623 continue;
625 *result_reg = reg;
626 if (lra_dump_file != NULL)
628 fprintf (lra_dump_file, " Reuse r%d for reload ", regno);
629 dump_value_slim (lra_dump_file, original, 1);
631 if (new_class != lra_get_allocno_class (regno))
632 lra_change_class (regno, new_class, ", change to", false);
633 if (lra_dump_file != NULL)
634 fprintf (lra_dump_file, "\n");
635 return false;
637 *result_reg = lra_create_new_reg (mode, original, rclass, title);
638 lra_assert (curr_insn_input_reloads_num < LRA_MAX_INSN_RELOADS);
639 curr_insn_input_reloads[curr_insn_input_reloads_num].input = original;
640 curr_insn_input_reloads[curr_insn_input_reloads_num++].reg = *result_reg;
641 return true;
646 /* The page contains code to extract memory address parts. */
648 /* Wrapper around REGNO_OK_FOR_INDEX_P, to allow pseudos. */
649 static inline bool
650 ok_for_index_p_nonstrict (rtx reg)
652 unsigned regno = REGNO (reg);
654 return regno >= FIRST_PSEUDO_REGISTER || REGNO_OK_FOR_INDEX_P (regno);
657 /* A version of regno_ok_for_base_p for use here, when all pseudos
658 should count as OK. Arguments as for regno_ok_for_base_p. */
659 static inline bool
660 ok_for_base_p_nonstrict (rtx reg, machine_mode mode, addr_space_t as,
661 enum rtx_code outer_code, enum rtx_code index_code)
663 unsigned regno = REGNO (reg);
665 if (regno >= FIRST_PSEUDO_REGISTER)
666 return true;
667 return ok_for_base_p_1 (regno, mode, as, outer_code, index_code);
672 /* The page contains major code to choose the current insn alternative
673 and generate reloads for it. */
675 /* Return the offset from REGNO of the least significant register
676 in (reg:MODE REGNO).
678 This function is used to tell whether two registers satisfy
679 a matching constraint. (reg:MODE1 REGNO1) matches (reg:MODE2 REGNO2) if:
681 REGNO1 + lra_constraint_offset (REGNO1, MODE1)
682 == REGNO2 + lra_constraint_offset (REGNO2, MODE2) */
684 lra_constraint_offset (int regno, machine_mode mode)
686 lra_assert (regno < FIRST_PSEUDO_REGISTER);
687 if (WORDS_BIG_ENDIAN && GET_MODE_SIZE (mode) > UNITS_PER_WORD
688 && SCALAR_INT_MODE_P (mode))
689 return hard_regno_nregs[regno][mode] - 1;
690 return 0;
693 /* Like rtx_equal_p except that it allows a REG and a SUBREG to match
694 if they are the same hard reg, and has special hacks for
695 auto-increment and auto-decrement. This is specifically intended for
696 process_alt_operands to use in determining whether two operands
697 match. X is the operand whose number is the lower of the two.
699 It is supposed that X is the output operand and Y is the input
700 operand. Y_HARD_REGNO is the final hard regno of register Y or
701 register in subreg Y as we know it now. Otherwise, it is a
702 negative value. */
703 static bool
704 operands_match_p (rtx x, rtx y, int y_hard_regno)
706 int i;
707 RTX_CODE code = GET_CODE (x);
708 const char *fmt;
710 if (x == y)
711 return true;
712 if ((code == REG || (code == SUBREG && REG_P (SUBREG_REG (x))))
713 && (REG_P (y) || (GET_CODE (y) == SUBREG && REG_P (SUBREG_REG (y)))))
715 int j;
717 i = get_hard_regno (x);
718 if (i < 0)
719 goto slow;
721 if ((j = y_hard_regno) < 0)
722 goto slow;
724 i += lra_constraint_offset (i, GET_MODE (x));
725 j += lra_constraint_offset (j, GET_MODE (y));
727 return i == j;
730 /* If two operands must match, because they are really a single
731 operand of an assembler insn, then two post-increments are invalid
732 because the assembler insn would increment only once. On the
733 other hand, a post-increment matches ordinary indexing if the
734 post-increment is the output operand. */
735 if (code == POST_DEC || code == POST_INC || code == POST_MODIFY)
736 return operands_match_p (XEXP (x, 0), y, y_hard_regno);
738 /* Two pre-increments are invalid because the assembler insn would
739 increment only once. On the other hand, a pre-increment matches
740 ordinary indexing if the pre-increment is the input operand. */
741 if (GET_CODE (y) == PRE_DEC || GET_CODE (y) == PRE_INC
742 || GET_CODE (y) == PRE_MODIFY)
743 return operands_match_p (x, XEXP (y, 0), -1);
745 slow:
747 if (code == REG && GET_CODE (y) == SUBREG && REG_P (SUBREG_REG (y))
748 && x == SUBREG_REG (y))
749 return true;
750 if (GET_CODE (y) == REG && code == SUBREG && REG_P (SUBREG_REG (x))
751 && SUBREG_REG (x) == y)
752 return true;
754 /* Now we have disposed of all the cases in which different rtx
755 codes can match. */
756 if (code != GET_CODE (y))
757 return false;
759 /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent. */
760 if (GET_MODE (x) != GET_MODE (y))
761 return false;
763 switch (code)
765 CASE_CONST_UNIQUE:
766 return false;
768 case LABEL_REF:
769 return LABEL_REF_LABEL (x) == LABEL_REF_LABEL (y);
770 case SYMBOL_REF:
771 return XSTR (x, 0) == XSTR (y, 0);
773 default:
774 break;
777 /* Compare the elements. If any pair of corresponding elements fail
778 to match, return false for the whole things. */
780 fmt = GET_RTX_FORMAT (code);
781 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
783 int val, j;
784 switch (fmt[i])
786 case 'w':
787 if (XWINT (x, i) != XWINT (y, i))
788 return false;
789 break;
791 case 'i':
792 if (XINT (x, i) != XINT (y, i))
793 return false;
794 break;
796 case 'e':
797 val = operands_match_p (XEXP (x, i), XEXP (y, i), -1);
798 if (val == 0)
799 return false;
800 break;
802 case '0':
803 break;
805 case 'E':
806 if (XVECLEN (x, i) != XVECLEN (y, i))
807 return false;
808 for (j = XVECLEN (x, i) - 1; j >= 0; --j)
810 val = operands_match_p (XVECEXP (x, i, j), XVECEXP (y, i, j), -1);
811 if (val == 0)
812 return false;
814 break;
816 /* It is believed that rtx's at this level will never
817 contain anything but integers and other rtx's, except for
818 within LABEL_REFs and SYMBOL_REFs. */
819 default:
820 gcc_unreachable ();
823 return true;
826 /* True if X is a constant that can be forced into the constant pool.
827 MODE is the mode of the operand, or VOIDmode if not known. */
828 #define CONST_POOL_OK_P(MODE, X) \
829 ((MODE) != VOIDmode \
830 && CONSTANT_P (X) \
831 && GET_CODE (X) != HIGH \
832 && !targetm.cannot_force_const_mem (MODE, X))
834 /* True if C is a non-empty register class that has too few registers
835 to be safely used as a reload target class. */
836 #define SMALL_REGISTER_CLASS_P(C) \
837 (ira_class_hard_regs_num [(C)] == 1 \
838 || (ira_class_hard_regs_num [(C)] >= 1 \
839 && targetm.class_likely_spilled_p (C)))
841 /* If REG is a reload pseudo, try to make its class satisfying CL. */
842 static void
843 narrow_reload_pseudo_class (rtx reg, enum reg_class cl)
845 enum reg_class rclass;
847 /* Do not make more accurate class from reloads generated. They are
848 mostly moves with a lot of constraints. Making more accurate
849 class may results in very narrow class and impossibility of find
850 registers for several reloads of one insn. */
851 if (INSN_UID (curr_insn) >= new_insn_uid_start)
852 return;
853 if (GET_CODE (reg) == SUBREG)
854 reg = SUBREG_REG (reg);
855 if (! REG_P (reg) || (int) REGNO (reg) < new_regno_start)
856 return;
857 if (in_class_p (reg, cl, &rclass) && rclass != cl)
858 lra_change_class (REGNO (reg), rclass, " Change to", true);
861 /* Generate reloads for matching OUT and INS (array of input operand
862 numbers with end marker -1) with reg class GOAL_CLASS. Add input
863 and output reloads correspondingly to the lists *BEFORE and *AFTER.
864 OUT might be negative. In this case we generate input reloads for
865 matched input operands INS. */
866 static void
867 match_reload (signed char out, signed char *ins, enum reg_class goal_class,
868 rtx_insn **before, rtx_insn **after)
870 int i, in;
871 rtx new_in_reg, new_out_reg, reg, clobber;
872 machine_mode inmode, outmode;
873 rtx in_rtx = *curr_id->operand_loc[ins[0]];
874 rtx out_rtx = out < 0 ? in_rtx : *curr_id->operand_loc[out];
876 inmode = curr_operand_mode[ins[0]];
877 outmode = out < 0 ? inmode : curr_operand_mode[out];
878 push_to_sequence (*before);
879 if (inmode != outmode)
881 if (GET_MODE_SIZE (inmode) > GET_MODE_SIZE (outmode))
883 reg = new_in_reg
884 = lra_create_new_reg_with_unique_value (inmode, in_rtx,
885 goal_class, "");
886 if (SCALAR_INT_MODE_P (inmode))
887 new_out_reg = gen_lowpart_SUBREG (outmode, reg);
888 else
889 new_out_reg = gen_rtx_SUBREG (outmode, reg, 0);
890 LRA_SUBREG_P (new_out_reg) = 1;
891 /* If the input reg is dying here, we can use the same hard
892 register for REG and IN_RTX. We do it only for original
893 pseudos as reload pseudos can die although original
894 pseudos still live where reload pseudos dies. */
895 if (REG_P (in_rtx) && (int) REGNO (in_rtx) < lra_new_regno_start
896 && find_regno_note (curr_insn, REG_DEAD, REGNO (in_rtx)))
897 lra_assign_reg_val (REGNO (in_rtx), REGNO (reg));
899 else
901 reg = new_out_reg
902 = lra_create_new_reg_with_unique_value (outmode, out_rtx,
903 goal_class, "");
904 if (SCALAR_INT_MODE_P (outmode))
905 new_in_reg = gen_lowpart_SUBREG (inmode, reg);
906 else
907 new_in_reg = gen_rtx_SUBREG (inmode, reg, 0);
908 /* NEW_IN_REG is non-paradoxical subreg. We don't want
909 NEW_OUT_REG living above. We add clobber clause for
910 this. This is just a temporary clobber. We can remove
911 it at the end of LRA work. */
912 clobber = emit_clobber (new_out_reg);
913 LRA_TEMP_CLOBBER_P (PATTERN (clobber)) = 1;
914 LRA_SUBREG_P (new_in_reg) = 1;
915 if (GET_CODE (in_rtx) == SUBREG)
917 rtx subreg_reg = SUBREG_REG (in_rtx);
919 /* If SUBREG_REG is dying here and sub-registers IN_RTX
920 and NEW_IN_REG are similar, we can use the same hard
921 register for REG and SUBREG_REG. */
922 if (REG_P (subreg_reg)
923 && (int) REGNO (subreg_reg) < lra_new_regno_start
924 && GET_MODE (subreg_reg) == outmode
925 && SUBREG_BYTE (in_rtx) == SUBREG_BYTE (new_in_reg)
926 && find_regno_note (curr_insn, REG_DEAD, REGNO (subreg_reg)))
927 lra_assign_reg_val (REGNO (subreg_reg), REGNO (reg));
931 else
933 /* Pseudos have values -- see comments for lra_reg_info.
934 Different pseudos with the same value do not conflict even if
935 they live in the same place. When we create a pseudo we
936 assign value of original pseudo (if any) from which we
937 created the new pseudo. If we create the pseudo from the
938 input pseudo, the new pseudo will no conflict with the input
939 pseudo which is wrong when the input pseudo lives after the
940 insn and as the new pseudo value is changed by the insn
941 output. Therefore we create the new pseudo from the output.
943 We cannot reuse the current output register because we might
944 have a situation like "a <- a op b", where the constraints
945 force the second input operand ("b") to match the output
946 operand ("a"). "b" must then be copied into a new register
947 so that it doesn't clobber the current value of "a". */
949 new_in_reg = new_out_reg
950 = lra_create_new_reg_with_unique_value (outmode, out_rtx,
951 goal_class, "");
953 /* In operand can be got from transformations before processing insn
954 constraints. One example of such transformations is subreg
955 reloading (see function simplify_operand_subreg). The new
956 pseudos created by the transformations might have inaccurate
957 class (ALL_REGS) and we should make their classes more
958 accurate. */
959 narrow_reload_pseudo_class (in_rtx, goal_class);
960 lra_emit_move (copy_rtx (new_in_reg), in_rtx);
961 *before = get_insns ();
962 end_sequence ();
963 for (i = 0; (in = ins[i]) >= 0; i++)
965 lra_assert
966 (GET_MODE (*curr_id->operand_loc[in]) == VOIDmode
967 || GET_MODE (new_in_reg) == GET_MODE (*curr_id->operand_loc[in]));
968 *curr_id->operand_loc[in] = new_in_reg;
970 lra_update_dups (curr_id, ins);
971 if (out < 0)
972 return;
973 /* See a comment for the input operand above. */
974 narrow_reload_pseudo_class (out_rtx, goal_class);
975 if (find_reg_note (curr_insn, REG_UNUSED, out_rtx) == NULL_RTX)
977 start_sequence ();
978 lra_emit_move (out_rtx, copy_rtx (new_out_reg));
979 emit_insn (*after);
980 *after = get_insns ();
981 end_sequence ();
983 *curr_id->operand_loc[out] = new_out_reg;
984 lra_update_dup (curr_id, out);
987 /* Return register class which is union of all reg classes in insn
988 constraint alternative string starting with P. */
989 static enum reg_class
990 reg_class_from_constraints (const char *p)
992 int c, len;
993 enum reg_class op_class = NO_REGS;
996 switch ((c = *p, len = CONSTRAINT_LEN (c, p)), c)
998 case '#':
999 case ',':
1000 return op_class;
1002 case 'g':
1003 op_class = reg_class_subunion[op_class][GENERAL_REGS];
1004 break;
1006 default:
1007 enum constraint_num cn = lookup_constraint (p);
1008 enum reg_class cl = reg_class_for_constraint (cn);
1009 if (cl == NO_REGS)
1011 if (insn_extra_address_constraint (cn))
1012 op_class
1013 = (reg_class_subunion
1014 [op_class][base_reg_class (VOIDmode, ADDR_SPACE_GENERIC,
1015 ADDRESS, SCRATCH)]);
1016 break;
1019 op_class = reg_class_subunion[op_class][cl];
1020 break;
1022 while ((p += len), c);
1023 return op_class;
1026 /* If OP is a register, return the class of the register as per
1027 get_reg_class, otherwise return NO_REGS. */
1028 static inline enum reg_class
1029 get_op_class (rtx op)
1031 return REG_P (op) ? get_reg_class (REGNO (op)) : NO_REGS;
1034 /* Return generated insn mem_pseudo:=val if TO_P or val:=mem_pseudo
1035 otherwise. If modes of MEM_PSEUDO and VAL are different, use
1036 SUBREG for VAL to make them equal. */
1037 static rtx_insn *
1038 emit_spill_move (bool to_p, rtx mem_pseudo, rtx val)
1040 if (GET_MODE (mem_pseudo) != GET_MODE (val))
1042 /* Usually size of mem_pseudo is greater than val size but in
1043 rare cases it can be less as it can be defined by target
1044 dependent macro HARD_REGNO_CALLER_SAVE_MODE. */
1045 if (! MEM_P (val))
1047 val = gen_rtx_SUBREG (GET_MODE (mem_pseudo),
1048 GET_CODE (val) == SUBREG ? SUBREG_REG (val) : val,
1050 LRA_SUBREG_P (val) = 1;
1052 else
1054 mem_pseudo = gen_lowpart_SUBREG (GET_MODE (val), mem_pseudo);
1055 LRA_SUBREG_P (mem_pseudo) = 1;
1058 return as_a <rtx_insn *> (to_p
1059 ? gen_move_insn (mem_pseudo, val)
1060 : gen_move_insn (val, mem_pseudo));
1063 /* Process a special case insn (register move), return true if we
1064 don't need to process it anymore. INSN should be a single set
1065 insn. Set up that RTL was changed through CHANGE_P and macro
1066 SECONDARY_MEMORY_NEEDED says to use secondary memory through
1067 SEC_MEM_P. */
1068 static bool
1069 check_and_process_move (bool *change_p, bool *sec_mem_p ATTRIBUTE_UNUSED)
1071 int sregno, dregno;
1072 rtx dest, src, dreg, sreg, old_sreg, new_reg, scratch_reg;
1073 rtx_insn *before;
1074 enum reg_class dclass, sclass, secondary_class;
1075 machine_mode sreg_mode;
1076 secondary_reload_info sri;
1078 lra_assert (curr_insn_set != NULL_RTX);
1079 dreg = dest = SET_DEST (curr_insn_set);
1080 sreg = src = SET_SRC (curr_insn_set);
1081 if (GET_CODE (dest) == SUBREG)
1082 dreg = SUBREG_REG (dest);
1083 if (GET_CODE (src) == SUBREG)
1084 sreg = SUBREG_REG (src);
1085 if (! (REG_P (dreg) || MEM_P (dreg)) || ! (REG_P (sreg) || MEM_P (sreg)))
1086 return false;
1087 sclass = dclass = NO_REGS;
1088 if (REG_P (dreg))
1089 dclass = get_reg_class (REGNO (dreg));
1090 if (dclass == ALL_REGS)
1091 /* ALL_REGS is used for new pseudos created by transformations
1092 like reload of SUBREG_REG (see function
1093 simplify_operand_subreg). We don't know their class yet. We
1094 should figure out the class from processing the insn
1095 constraints not in this fast path function. Even if ALL_REGS
1096 were a right class for the pseudo, secondary_... hooks usually
1097 are not define for ALL_REGS. */
1098 return false;
1099 sreg_mode = GET_MODE (sreg);
1100 old_sreg = sreg;
1101 if (REG_P (sreg))
1102 sclass = get_reg_class (REGNO (sreg));
1103 if (sclass == ALL_REGS)
1104 /* See comments above. */
1105 return false;
1106 if (sclass == NO_REGS && dclass == NO_REGS)
1107 return false;
1108 #ifdef SECONDARY_MEMORY_NEEDED
1109 if (SECONDARY_MEMORY_NEEDED (sclass, dclass, GET_MODE (src))
1110 #ifdef SECONDARY_MEMORY_NEEDED_MODE
1111 && ((sclass != NO_REGS && dclass != NO_REGS)
1112 || GET_MODE (src) != SECONDARY_MEMORY_NEEDED_MODE (GET_MODE (src)))
1113 #endif
1116 *sec_mem_p = true;
1117 return false;
1119 #endif
1120 if (! REG_P (dreg) || ! REG_P (sreg))
1121 return false;
1122 sri.prev_sri = NULL;
1123 sri.icode = CODE_FOR_nothing;
1124 sri.extra_cost = 0;
1125 secondary_class = NO_REGS;
1126 /* Set up hard register for a reload pseudo for hook
1127 secondary_reload because some targets just ignore unassigned
1128 pseudos in the hook. */
1129 if (dclass != NO_REGS && lra_get_regno_hard_regno (REGNO (dreg)) < 0)
1131 dregno = REGNO (dreg);
1132 reg_renumber[dregno] = ira_class_hard_regs[dclass][0];
1134 else
1135 dregno = -1;
1136 if (sclass != NO_REGS && lra_get_regno_hard_regno (REGNO (sreg)) < 0)
1138 sregno = REGNO (sreg);
1139 reg_renumber[sregno] = ira_class_hard_regs[sclass][0];
1141 else
1142 sregno = -1;
1143 if (sclass != NO_REGS)
1144 secondary_class
1145 = (enum reg_class) targetm.secondary_reload (false, dest,
1146 (reg_class_t) sclass,
1147 GET_MODE (src), &sri);
1148 if (sclass == NO_REGS
1149 || ((secondary_class != NO_REGS || sri.icode != CODE_FOR_nothing)
1150 && dclass != NO_REGS))
1152 enum reg_class old_sclass = secondary_class;
1153 secondary_reload_info old_sri = sri;
1155 sri.prev_sri = NULL;
1156 sri.icode = CODE_FOR_nothing;
1157 sri.extra_cost = 0;
1158 secondary_class
1159 = (enum reg_class) targetm.secondary_reload (true, sreg,
1160 (reg_class_t) dclass,
1161 sreg_mode, &sri);
1162 /* Check the target hook consistency. */
1163 lra_assert
1164 ((secondary_class == NO_REGS && sri.icode == CODE_FOR_nothing)
1165 || (old_sclass == NO_REGS && old_sri.icode == CODE_FOR_nothing)
1166 || (secondary_class == old_sclass && sri.icode == old_sri.icode));
1168 if (sregno >= 0)
1169 reg_renumber [sregno] = -1;
1170 if (dregno >= 0)
1171 reg_renumber [dregno] = -1;
1172 if (secondary_class == NO_REGS && sri.icode == CODE_FOR_nothing)
1173 return false;
1174 *change_p = true;
1175 new_reg = NULL_RTX;
1176 if (secondary_class != NO_REGS)
1177 new_reg = lra_create_new_reg_with_unique_value (sreg_mode, NULL_RTX,
1178 secondary_class,
1179 "secondary");
1180 start_sequence ();
1181 if (old_sreg != sreg)
1182 sreg = copy_rtx (sreg);
1183 if (sri.icode == CODE_FOR_nothing)
1184 lra_emit_move (new_reg, sreg);
1185 else
1187 enum reg_class scratch_class;
1189 scratch_class = (reg_class_from_constraints
1190 (insn_data[sri.icode].operand[2].constraint));
1191 scratch_reg = (lra_create_new_reg_with_unique_value
1192 (insn_data[sri.icode].operand[2].mode, NULL_RTX,
1193 scratch_class, "scratch"));
1194 emit_insn (GEN_FCN (sri.icode) (new_reg != NULL_RTX ? new_reg : dest,
1195 sreg, scratch_reg));
1197 before = get_insns ();
1198 end_sequence ();
1199 lra_process_new_insns (curr_insn, before, NULL, "Inserting the move");
1200 if (new_reg != NULL_RTX)
1202 if (GET_CODE (src) == SUBREG)
1203 SUBREG_REG (src) = new_reg;
1204 else
1205 SET_SRC (curr_insn_set) = new_reg;
1207 else
1209 if (lra_dump_file != NULL)
1211 fprintf (lra_dump_file, "Deleting move %u\n", INSN_UID (curr_insn));
1212 dump_insn_slim (lra_dump_file, curr_insn);
1214 lra_set_insn_deleted (curr_insn);
1215 return true;
1217 return false;
1220 /* The following data describe the result of process_alt_operands.
1221 The data are used in curr_insn_transform to generate reloads. */
1223 /* The chosen reg classes which should be used for the corresponding
1224 operands. */
1225 static enum reg_class goal_alt[MAX_RECOG_OPERANDS];
1226 /* True if the operand should be the same as another operand and that
1227 other operand does not need a reload. */
1228 static bool goal_alt_match_win[MAX_RECOG_OPERANDS];
1229 /* True if the operand does not need a reload. */
1230 static bool goal_alt_win[MAX_RECOG_OPERANDS];
1231 /* True if the operand can be offsetable memory. */
1232 static bool goal_alt_offmemok[MAX_RECOG_OPERANDS];
1233 /* The number of an operand to which given operand can be matched to. */
1234 static int goal_alt_matches[MAX_RECOG_OPERANDS];
1235 /* The number of elements in the following array. */
1236 static int goal_alt_dont_inherit_ops_num;
1237 /* Numbers of operands whose reload pseudos should not be inherited. */
1238 static int goal_alt_dont_inherit_ops[MAX_RECOG_OPERANDS];
1239 /* True if the insn commutative operands should be swapped. */
1240 static bool goal_alt_swapped;
1241 /* The chosen insn alternative. */
1242 static int goal_alt_number;
1244 /* The following five variables are used to choose the best insn
1245 alternative. They reflect final characteristics of the best
1246 alternative. */
1248 /* Number of necessary reloads and overall cost reflecting the
1249 previous value and other unpleasantness of the best alternative. */
1250 static int best_losers, best_overall;
1251 /* Overall number hard registers used for reloads. For example, on
1252 some targets we need 2 general registers to reload DFmode and only
1253 one floating point register. */
1254 static int best_reload_nregs;
1255 /* Overall number reflecting distances of previous reloading the same
1256 value. The distances are counted from the current BB start. It is
1257 used to improve inheritance chances. */
1258 static int best_reload_sum;
1260 /* True if the current insn should have no correspondingly input or
1261 output reloads. */
1262 static bool no_input_reloads_p, no_output_reloads_p;
1264 /* True if we swapped the commutative operands in the current
1265 insn. */
1266 static int curr_swapped;
1268 /* if CHECK_ONLY_P is false, arrange for address element *LOC to be a
1269 register of class CL. Add any input reloads to list BEFORE. AFTER
1270 is nonnull if *LOC is an automodified value; handle that case by
1271 adding the required output reloads to list AFTER. Return true if
1272 the RTL was changed.
1274 if CHECK_ONLY_P is true, check that the *LOC is a correct address
1275 register. Return false if the address register is correct. */
1276 static bool
1277 process_addr_reg (rtx *loc, bool check_only_p, rtx_insn **before, rtx_insn **after,
1278 enum reg_class cl)
1280 int regno;
1281 enum reg_class rclass, new_class;
1282 rtx reg;
1283 rtx new_reg;
1284 machine_mode mode;
1285 bool subreg_p, before_p = false;
1287 subreg_p = GET_CODE (*loc) == SUBREG;
1288 if (subreg_p)
1289 loc = &SUBREG_REG (*loc);
1290 reg = *loc;
1291 mode = GET_MODE (reg);
1292 if (! REG_P (reg))
1294 if (check_only_p)
1295 return true;
1296 /* Always reload memory in an address even if the target supports
1297 such addresses. */
1298 new_reg = lra_create_new_reg_with_unique_value (mode, reg, cl, "address");
1299 before_p = true;
1301 else
1303 regno = REGNO (reg);
1304 rclass = get_reg_class (regno);
1305 if (! check_only_p
1306 && (*loc = get_equiv_with_elimination (reg, curr_insn)) != reg)
1308 if (lra_dump_file != NULL)
1310 fprintf (lra_dump_file,
1311 "Changing pseudo %d in address of insn %u on equiv ",
1312 REGNO (reg), INSN_UID (curr_insn));
1313 dump_value_slim (lra_dump_file, *loc, 1);
1314 fprintf (lra_dump_file, "\n");
1316 *loc = copy_rtx (*loc);
1318 if (*loc != reg || ! in_class_p (reg, cl, &new_class))
1320 if (check_only_p)
1321 return true;
1322 reg = *loc;
1323 if (get_reload_reg (after == NULL ? OP_IN : OP_INOUT,
1324 mode, reg, cl, subreg_p, "address", &new_reg))
1325 before_p = true;
1327 else if (new_class != NO_REGS && rclass != new_class)
1329 if (check_only_p)
1330 return true;
1331 lra_change_class (regno, new_class, " Change to", true);
1332 return false;
1334 else
1335 return false;
1337 if (before_p)
1339 push_to_sequence (*before);
1340 lra_emit_move (new_reg, reg);
1341 *before = get_insns ();
1342 end_sequence ();
1344 *loc = new_reg;
1345 if (after != NULL)
1347 start_sequence ();
1348 lra_emit_move (reg, new_reg);
1349 emit_insn (*after);
1350 *after = get_insns ();
1351 end_sequence ();
1353 return true;
1356 /* Insert move insn in simplify_operand_subreg. BEFORE returns
1357 the insn to be inserted before curr insn. AFTER returns the
1358 the insn to be inserted after curr insn. ORIGREG and NEWREG
1359 are the original reg and new reg for reload. */
1360 static void
1361 insert_move_for_subreg (rtx_insn **before, rtx_insn **after, rtx origreg,
1362 rtx newreg)
1364 if (before)
1366 push_to_sequence (*before);
1367 lra_emit_move (newreg, origreg);
1368 *before = get_insns ();
1369 end_sequence ();
1371 if (after)
1373 start_sequence ();
1374 lra_emit_move (origreg, newreg);
1375 emit_insn (*after);
1376 *after = get_insns ();
1377 end_sequence ();
1381 static int valid_address_p (machine_mode mode, rtx addr, addr_space_t as);
1383 /* Make reloads for subreg in operand NOP with internal subreg mode
1384 REG_MODE, add new reloads for further processing. Return true if
1385 any reload was generated. */
1386 static bool
1387 simplify_operand_subreg (int nop, machine_mode reg_mode)
1389 int hard_regno;
1390 rtx_insn *before, *after;
1391 machine_mode mode;
1392 rtx reg, new_reg;
1393 rtx operand = *curr_id->operand_loc[nop];
1394 enum reg_class regclass;
1395 enum op_type type;
1397 before = after = NULL;
1399 if (GET_CODE (operand) != SUBREG)
1400 return false;
1402 mode = GET_MODE (operand);
1403 reg = SUBREG_REG (operand);
1404 type = curr_static_id->operand[nop].type;
1405 /* If we change address for paradoxical subreg of memory, the
1406 address might violate the necessary alignment or the access might
1407 be slow. So take this into consideration. We should not worry
1408 about access beyond allocated memory for paradoxical memory
1409 subregs as we don't substitute such equiv memory (see processing
1410 equivalences in function lra_constraints) and because for spilled
1411 pseudos we allocate stack memory enough for the biggest
1412 corresponding paradoxical subreg. */
1413 if (MEM_P (reg)
1414 && (! SLOW_UNALIGNED_ACCESS (mode, MEM_ALIGN (reg))
1415 || MEM_ALIGN (reg) >= GET_MODE_ALIGNMENT (mode)))
1417 rtx subst, old = *curr_id->operand_loc[nop];
1419 alter_subreg (curr_id->operand_loc[nop], false);
1420 subst = *curr_id->operand_loc[nop];
1421 lra_assert (MEM_P (subst));
1422 if (! valid_address_p (GET_MODE (reg), XEXP (reg, 0),
1423 MEM_ADDR_SPACE (reg))
1424 || valid_address_p (GET_MODE (subst), XEXP (subst, 0),
1425 MEM_ADDR_SPACE (subst)))
1426 return true;
1427 /* If the address was valid and became invalid, prefer to reload
1428 the memory. Typical case is when the index scale should
1429 correspond the memory. */
1430 *curr_id->operand_loc[nop] = old;
1432 else if (REG_P (reg) && REGNO (reg) < FIRST_PSEUDO_REGISTER)
1434 alter_subreg (curr_id->operand_loc[nop], false);
1435 return true;
1437 /* Put constant into memory when we have mixed modes. It generates
1438 a better code in most cases as it does not need a secondary
1439 reload memory. It also prevents LRA looping when LRA is using
1440 secondary reload memory again and again. */
1441 if (CONSTANT_P (reg) && CONST_POOL_OK_P (reg_mode, reg)
1442 && SCALAR_INT_MODE_P (reg_mode) != SCALAR_INT_MODE_P (mode))
1444 SUBREG_REG (operand) = force_const_mem (reg_mode, reg);
1445 alter_subreg (curr_id->operand_loc[nop], false);
1446 return true;
1448 /* Force a reload of the SUBREG_REG if this is a constant or PLUS or
1449 if there may be a problem accessing OPERAND in the outer
1450 mode. */
1451 if ((REG_P (reg)
1452 && REGNO (reg) >= FIRST_PSEUDO_REGISTER
1453 && (hard_regno = lra_get_regno_hard_regno (REGNO (reg))) >= 0
1454 /* Don't reload paradoxical subregs because we could be looping
1455 having repeatedly final regno out of hard regs range. */
1456 && (hard_regno_nregs[hard_regno][GET_MODE (reg)]
1457 >= hard_regno_nregs[hard_regno][mode])
1458 && simplify_subreg_regno (hard_regno, GET_MODE (reg),
1459 SUBREG_BYTE (operand), mode) < 0
1460 /* Don't reload subreg for matching reload. It is actually
1461 valid subreg in LRA. */
1462 && ! LRA_SUBREG_P (operand))
1463 || CONSTANT_P (reg) || GET_CODE (reg) == PLUS || MEM_P (reg))
1465 enum reg_class rclass;
1467 if (REG_P (reg))
1468 /* There is a big probability that we will get the same class
1469 for the new pseudo and we will get the same insn which
1470 means infinite looping. So spill the new pseudo. */
1471 rclass = NO_REGS;
1472 else
1473 /* The class will be defined later in curr_insn_transform. */
1474 rclass
1475 = (enum reg_class) targetm.preferred_reload_class (reg, ALL_REGS);
1477 if (get_reload_reg (curr_static_id->operand[nop].type, reg_mode, reg,
1478 rclass, TRUE, "subreg reg", &new_reg))
1480 bool insert_before, insert_after;
1481 bitmap_set_bit (&lra_subreg_reload_pseudos, REGNO (new_reg));
1483 insert_before = (type != OP_OUT
1484 || GET_MODE_SIZE (GET_MODE (reg)) > GET_MODE_SIZE (mode));
1485 insert_after = (type != OP_IN);
1486 insert_move_for_subreg (insert_before ? &before : NULL,
1487 insert_after ? &after : NULL,
1488 reg, new_reg);
1490 SUBREG_REG (operand) = new_reg;
1491 lra_process_new_insns (curr_insn, before, after,
1492 "Inserting subreg reload");
1493 return true;
1495 /* Force a reload for a paradoxical subreg. For paradoxical subreg,
1496 IRA allocates hardreg to the inner pseudo reg according to its mode
1497 instead of the outermode, so the size of the hardreg may not be enough
1498 to contain the outermode operand, in that case we may need to insert
1499 reload for the reg. For the following two types of paradoxical subreg,
1500 we need to insert reload:
1501 1. If the op_type is OP_IN, and the hardreg could not be paired with
1502 other hardreg to contain the outermode operand
1503 (checked by in_hard_reg_set_p), we need to insert the reload.
1504 2. If the op_type is OP_OUT or OP_INOUT.
1506 Here is a paradoxical subreg example showing how the reload is generated:
1508 (insn 5 4 7 2 (set (reg:TI 106 [ __comp ])
1509 (subreg:TI (reg:DI 107 [ __comp ]) 0)) {*movti_internal_rex64}
1511 In IRA, reg107 is allocated to a DImode hardreg. We use x86-64 as example
1512 here, if reg107 is assigned to hardreg R15, because R15 is the last
1513 hardreg, compiler cannot find another hardreg to pair with R15 to
1514 contain TImode data. So we insert a TImode reload reg180 for it.
1515 After reload is inserted:
1517 (insn 283 0 0 (set (subreg:DI (reg:TI 180 [orig:107 __comp ] [107]) 0)
1518 (reg:DI 107 [ __comp ])) -1
1519 (insn 5 4 7 2 (set (reg:TI 106 [ __comp ])
1520 (subreg:TI (reg:TI 180 [orig:107 __comp ] [107]) 0)) {*movti_internal_rex64}
1522 Two reload hard registers will be allocated to reg180 to save TImode data
1523 in LRA_assign. */
1524 else if (REG_P (reg)
1525 && REGNO (reg) >= FIRST_PSEUDO_REGISTER
1526 && (hard_regno = lra_get_regno_hard_regno (REGNO (reg))) >= 0
1527 && (hard_regno_nregs[hard_regno][GET_MODE (reg)]
1528 < hard_regno_nregs[hard_regno][mode])
1529 && (regclass = lra_get_allocno_class (REGNO (reg)))
1530 && (type != OP_IN
1531 || !in_hard_reg_set_p (reg_class_contents[regclass],
1532 mode, hard_regno)))
1534 /* The class will be defined later in curr_insn_transform. */
1535 enum reg_class rclass
1536 = (enum reg_class) targetm.preferred_reload_class (reg, ALL_REGS);
1538 if (get_reload_reg (curr_static_id->operand[nop].type, mode, reg,
1539 rclass, TRUE, "paradoxical subreg", &new_reg))
1541 rtx subreg;
1542 bool insert_before, insert_after;
1544 PUT_MODE (new_reg, mode);
1545 subreg = simplify_gen_subreg (GET_MODE (reg), new_reg, mode, 0);
1546 bitmap_set_bit (&lra_subreg_reload_pseudos, REGNO (new_reg));
1548 insert_before = (type != OP_OUT);
1549 insert_after = (type != OP_IN);
1550 insert_move_for_subreg (insert_before ? &before : NULL,
1551 insert_after ? &after : NULL,
1552 reg, subreg);
1554 SUBREG_REG (operand) = new_reg;
1555 lra_process_new_insns (curr_insn, before, after,
1556 "Inserting paradoxical subreg reload");
1557 return true;
1559 return false;
1562 /* Return TRUE if X refers for a hard register from SET. */
1563 static bool
1564 uses_hard_regs_p (rtx x, HARD_REG_SET set)
1566 int i, j, x_hard_regno;
1567 machine_mode mode;
1568 const char *fmt;
1569 enum rtx_code code;
1571 if (x == NULL_RTX)
1572 return false;
1573 code = GET_CODE (x);
1574 mode = GET_MODE (x);
1575 if (code == SUBREG)
1577 x = SUBREG_REG (x);
1578 code = GET_CODE (x);
1579 if (GET_MODE_SIZE (GET_MODE (x)) > GET_MODE_SIZE (mode))
1580 mode = GET_MODE (x);
1583 if (REG_P (x))
1585 x_hard_regno = get_hard_regno (x);
1586 return (x_hard_regno >= 0
1587 && overlaps_hard_reg_set_p (set, mode, x_hard_regno));
1589 if (MEM_P (x))
1591 struct address_info ad;
1593 decompose_mem_address (&ad, x);
1594 if (ad.base_term != NULL && uses_hard_regs_p (*ad.base_term, set))
1595 return true;
1596 if (ad.index_term != NULL && uses_hard_regs_p (*ad.index_term, set))
1597 return true;
1599 fmt = GET_RTX_FORMAT (code);
1600 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1602 if (fmt[i] == 'e')
1604 if (uses_hard_regs_p (XEXP (x, i), set))
1605 return true;
1607 else if (fmt[i] == 'E')
1609 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
1610 if (uses_hard_regs_p (XVECEXP (x, i, j), set))
1611 return true;
1614 return false;
1617 /* Return true if OP is a spilled pseudo. */
1618 static inline bool
1619 spilled_pseudo_p (rtx op)
1621 return (REG_P (op)
1622 && REGNO (op) >= FIRST_PSEUDO_REGISTER && in_mem_p (REGNO (op)));
1625 /* Return true if X is a general constant. */
1626 static inline bool
1627 general_constant_p (rtx x)
1629 return CONSTANT_P (x) && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (x));
1632 static bool
1633 reg_in_class_p (rtx reg, enum reg_class cl)
1635 if (cl == NO_REGS)
1636 return get_reg_class (REGNO (reg)) == NO_REGS;
1637 return in_class_p (reg, cl, NULL);
1640 /* Major function to choose the current insn alternative and what
1641 operands should be reloaded and how. If ONLY_ALTERNATIVE is not
1642 negative we should consider only this alternative. Return false if
1643 we can not choose the alternative or find how to reload the
1644 operands. */
1645 static bool
1646 process_alt_operands (int only_alternative)
1648 bool ok_p = false;
1649 int nop, overall, nalt;
1650 int n_alternatives = curr_static_id->n_alternatives;
1651 int n_operands = curr_static_id->n_operands;
1652 /* LOSERS counts the operands that don't fit this alternative and
1653 would require loading. */
1654 int losers;
1655 /* REJECT is a count of how undesirable this alternative says it is
1656 if any reloading is required. If the alternative matches exactly
1657 then REJECT is ignored, but otherwise it gets this much counted
1658 against it in addition to the reloading needed. */
1659 int reject;
1660 int op_reject;
1661 /* The number of elements in the following array. */
1662 int early_clobbered_regs_num;
1663 /* Numbers of operands which are early clobber registers. */
1664 int early_clobbered_nops[MAX_RECOG_OPERANDS];
1665 enum reg_class curr_alt[MAX_RECOG_OPERANDS];
1666 HARD_REG_SET curr_alt_set[MAX_RECOG_OPERANDS];
1667 bool curr_alt_match_win[MAX_RECOG_OPERANDS];
1668 bool curr_alt_win[MAX_RECOG_OPERANDS];
1669 bool curr_alt_offmemok[MAX_RECOG_OPERANDS];
1670 int curr_alt_matches[MAX_RECOG_OPERANDS];
1671 /* The number of elements in the following array. */
1672 int curr_alt_dont_inherit_ops_num;
1673 /* Numbers of operands whose reload pseudos should not be inherited. */
1674 int curr_alt_dont_inherit_ops[MAX_RECOG_OPERANDS];
1675 rtx op;
1676 /* The register when the operand is a subreg of register, otherwise the
1677 operand itself. */
1678 rtx no_subreg_reg_operand[MAX_RECOG_OPERANDS];
1679 /* The register if the operand is a register or subreg of register,
1680 otherwise NULL. */
1681 rtx operand_reg[MAX_RECOG_OPERANDS];
1682 int hard_regno[MAX_RECOG_OPERANDS];
1683 machine_mode biggest_mode[MAX_RECOG_OPERANDS];
1684 int reload_nregs, reload_sum;
1685 bool costly_p;
1686 enum reg_class cl;
1688 /* Calculate some data common for all alternatives to speed up the
1689 function. */
1690 for (nop = 0; nop < n_operands; nop++)
1692 rtx reg;
1694 op = no_subreg_reg_operand[nop] = *curr_id->operand_loc[nop];
1695 /* The real hard regno of the operand after the allocation. */
1696 hard_regno[nop] = get_hard_regno (op);
1698 operand_reg[nop] = reg = op;
1699 biggest_mode[nop] = GET_MODE (op);
1700 if (GET_CODE (op) == SUBREG)
1702 operand_reg[nop] = reg = SUBREG_REG (op);
1703 if (GET_MODE_SIZE (biggest_mode[nop])
1704 < GET_MODE_SIZE (GET_MODE (reg)))
1705 biggest_mode[nop] = GET_MODE (reg);
1707 if (! REG_P (reg))
1708 operand_reg[nop] = NULL_RTX;
1709 else if (REGNO (reg) >= FIRST_PSEUDO_REGISTER
1710 || ((int) REGNO (reg)
1711 == lra_get_elimination_hard_regno (REGNO (reg))))
1712 no_subreg_reg_operand[nop] = reg;
1713 else
1714 operand_reg[nop] = no_subreg_reg_operand[nop]
1715 /* Just use natural mode for elimination result. It should
1716 be enough for extra constraints hooks. */
1717 = regno_reg_rtx[hard_regno[nop]];
1720 /* The constraints are made of several alternatives. Each operand's
1721 constraint looks like foo,bar,... with commas separating the
1722 alternatives. The first alternatives for all operands go
1723 together, the second alternatives go together, etc.
1725 First loop over alternatives. */
1726 alternative_mask preferred = curr_id->preferred_alternatives;
1727 if (only_alternative >= 0)
1728 preferred &= ALTERNATIVE_BIT (only_alternative);
1730 for (nalt = 0; nalt < n_alternatives; nalt++)
1732 /* Loop over operands for one constraint alternative. */
1733 if (!TEST_BIT (preferred, nalt))
1734 continue;
1736 overall = losers = reject = reload_nregs = reload_sum = 0;
1737 for (nop = 0; nop < n_operands; nop++)
1739 int inc = (curr_static_id
1740 ->operand_alternative[nalt * n_operands + nop].reject);
1741 if (lra_dump_file != NULL && inc != 0)
1742 fprintf (lra_dump_file,
1743 " Staticly defined alt reject+=%d\n", inc);
1744 reject += inc;
1746 early_clobbered_regs_num = 0;
1748 for (nop = 0; nop < n_operands; nop++)
1750 const char *p;
1751 char *end;
1752 int len, c, m, i, opalt_num, this_alternative_matches;
1753 bool win, did_match, offmemok, early_clobber_p;
1754 /* false => this operand can be reloaded somehow for this
1755 alternative. */
1756 bool badop;
1757 /* true => this operand can be reloaded if the alternative
1758 allows regs. */
1759 bool winreg;
1760 /* True if a constant forced into memory would be OK for
1761 this operand. */
1762 bool constmemok;
1763 enum reg_class this_alternative, this_costly_alternative;
1764 HARD_REG_SET this_alternative_set, this_costly_alternative_set;
1765 bool this_alternative_match_win, this_alternative_win;
1766 bool this_alternative_offmemok;
1767 bool scratch_p;
1768 machine_mode mode;
1769 enum constraint_num cn;
1771 opalt_num = nalt * n_operands + nop;
1772 if (curr_static_id->operand_alternative[opalt_num].anything_ok)
1774 /* Fast track for no constraints at all. */
1775 curr_alt[nop] = NO_REGS;
1776 CLEAR_HARD_REG_SET (curr_alt_set[nop]);
1777 curr_alt_win[nop] = true;
1778 curr_alt_match_win[nop] = false;
1779 curr_alt_offmemok[nop] = false;
1780 curr_alt_matches[nop] = -1;
1781 continue;
1784 op = no_subreg_reg_operand[nop];
1785 mode = curr_operand_mode[nop];
1787 win = did_match = winreg = offmemok = constmemok = false;
1788 badop = true;
1790 early_clobber_p = false;
1791 p = curr_static_id->operand_alternative[opalt_num].constraint;
1793 this_costly_alternative = this_alternative = NO_REGS;
1794 /* We update set of possible hard regs besides its class
1795 because reg class might be inaccurate. For example,
1796 union of LO_REGS (l), HI_REGS(h), and STACK_REG(k) in ARM
1797 is translated in HI_REGS because classes are merged by
1798 pairs and there is no accurate intermediate class. */
1799 CLEAR_HARD_REG_SET (this_alternative_set);
1800 CLEAR_HARD_REG_SET (this_costly_alternative_set);
1801 this_alternative_win = false;
1802 this_alternative_match_win = false;
1803 this_alternative_offmemok = false;
1804 this_alternative_matches = -1;
1806 /* An empty constraint should be excluded by the fast
1807 track. */
1808 lra_assert (*p != 0 && *p != ',');
1810 op_reject = 0;
1811 /* Scan this alternative's specs for this operand; set WIN
1812 if the operand fits any letter in this alternative.
1813 Otherwise, clear BADOP if this operand could fit some
1814 letter after reloads, or set WINREG if this operand could
1815 fit after reloads provided the constraint allows some
1816 registers. */
1817 costly_p = false;
1820 switch ((c = *p, len = CONSTRAINT_LEN (c, p)), c)
1822 case '\0':
1823 len = 0;
1824 break;
1825 case ',':
1826 c = '\0';
1827 break;
1829 case '&':
1830 early_clobber_p = true;
1831 break;
1833 case '$':
1834 op_reject += LRA_MAX_REJECT;
1835 break;
1836 case '^':
1837 op_reject += LRA_LOSER_COST_FACTOR;
1838 break;
1840 case '#':
1841 /* Ignore rest of this alternative. */
1842 c = '\0';
1843 break;
1845 case '0': case '1': case '2': case '3': case '4':
1846 case '5': case '6': case '7': case '8': case '9':
1848 int m_hregno;
1849 bool match_p;
1851 m = strtoul (p, &end, 10);
1852 p = end;
1853 len = 0;
1854 lra_assert (nop > m);
1856 this_alternative_matches = m;
1857 m_hregno = get_hard_regno (*curr_id->operand_loc[m]);
1858 /* We are supposed to match a previous operand.
1859 If we do, we win if that one did. If we do
1860 not, count both of the operands as losers.
1861 (This is too conservative, since most of the
1862 time only a single reload insn will be needed
1863 to make the two operands win. As a result,
1864 this alternative may be rejected when it is
1865 actually desirable.) */
1866 match_p = false;
1867 if (operands_match_p (*curr_id->operand_loc[nop],
1868 *curr_id->operand_loc[m], m_hregno))
1870 /* We should reject matching of an early
1871 clobber operand if the matching operand is
1872 not dying in the insn. */
1873 if (! curr_static_id->operand[m].early_clobber
1874 || operand_reg[nop] == NULL_RTX
1875 || (find_regno_note (curr_insn, REG_DEAD,
1876 REGNO (op))
1877 || REGNO (op) == REGNO (operand_reg[m])))
1878 match_p = true;
1880 if (match_p)
1882 /* If we are matching a non-offsettable
1883 address where an offsettable address was
1884 expected, then we must reject this
1885 combination, because we can't reload
1886 it. */
1887 if (curr_alt_offmemok[m]
1888 && MEM_P (*curr_id->operand_loc[m])
1889 && curr_alt[m] == NO_REGS && ! curr_alt_win[m])
1890 continue;
1892 else
1894 /* Operands don't match. Both operands must
1895 allow a reload register, otherwise we
1896 cannot make them match. */
1897 if (curr_alt[m] == NO_REGS)
1898 break;
1899 /* Retroactively mark the operand we had to
1900 match as a loser, if it wasn't already and
1901 it wasn't matched to a register constraint
1902 (e.g it might be matched by memory). */
1903 if (curr_alt_win[m]
1904 && (operand_reg[m] == NULL_RTX
1905 || hard_regno[m] < 0))
1907 losers++;
1908 reload_nregs
1909 += (ira_reg_class_max_nregs[curr_alt[m]]
1910 [GET_MODE (*curr_id->operand_loc[m])]);
1913 /* Prefer matching earlyclobber alternative as
1914 it results in less hard regs required for
1915 the insn than a non-matching earlyclobber
1916 alternative. */
1917 if (curr_static_id->operand[m].early_clobber)
1919 if (lra_dump_file != NULL)
1920 fprintf
1921 (lra_dump_file,
1922 " %d Matching earlyclobber alt:"
1923 " reject--\n",
1924 nop);
1925 reject--;
1927 /* Otherwise we prefer no matching
1928 alternatives because it gives more freedom
1929 in RA. */
1930 else if (operand_reg[nop] == NULL_RTX
1931 || (find_regno_note (curr_insn, REG_DEAD,
1932 REGNO (operand_reg[nop]))
1933 == NULL_RTX))
1935 if (lra_dump_file != NULL)
1936 fprintf
1937 (lra_dump_file,
1938 " %d Matching alt: reject+=2\n",
1939 nop);
1940 reject += 2;
1943 /* If we have to reload this operand and some
1944 previous operand also had to match the same
1945 thing as this operand, we don't know how to do
1946 that. */
1947 if (!match_p || !curr_alt_win[m])
1949 for (i = 0; i < nop; i++)
1950 if (curr_alt_matches[i] == m)
1951 break;
1952 if (i < nop)
1953 break;
1955 else
1956 did_match = true;
1958 /* This can be fixed with reloads if the operand
1959 we are supposed to match can be fixed with
1960 reloads. */
1961 badop = false;
1962 this_alternative = curr_alt[m];
1963 COPY_HARD_REG_SET (this_alternative_set, curr_alt_set[m]);
1964 winreg = this_alternative != NO_REGS;
1965 break;
1968 case 'g':
1969 if (MEM_P (op)
1970 || general_constant_p (op)
1971 || spilled_pseudo_p (op))
1972 win = true;
1973 cl = GENERAL_REGS;
1974 goto reg;
1976 default:
1977 cn = lookup_constraint (p);
1978 switch (get_constraint_type (cn))
1980 case CT_REGISTER:
1981 cl = reg_class_for_constraint (cn);
1982 if (cl != NO_REGS)
1983 goto reg;
1984 break;
1986 case CT_CONST_INT:
1987 if (CONST_INT_P (op)
1988 && insn_const_int_ok_for_constraint (INTVAL (op), cn))
1989 win = true;
1990 break;
1992 case CT_MEMORY:
1993 if (MEM_P (op)
1994 && satisfies_memory_constraint_p (op, cn))
1995 win = true;
1996 else if (spilled_pseudo_p (op))
1997 win = true;
1999 /* If we didn't already win, we can reload constants
2000 via force_const_mem or put the pseudo value into
2001 memory, or make other memory by reloading the
2002 address like for 'o'. */
2003 if (CONST_POOL_OK_P (mode, op)
2004 || MEM_P (op) || REG_P (op))
2005 badop = false;
2006 constmemok = true;
2007 offmemok = true;
2008 break;
2010 case CT_ADDRESS:
2011 /* If we didn't already win, we can reload the address
2012 into a base register. */
2013 if (satisfies_address_constraint_p (op, cn))
2014 win = true;
2015 cl = base_reg_class (VOIDmode, ADDR_SPACE_GENERIC,
2016 ADDRESS, SCRATCH);
2017 badop = false;
2018 goto reg;
2020 case CT_FIXED_FORM:
2021 if (constraint_satisfied_p (op, cn))
2022 win = true;
2023 break;
2025 break;
2027 reg:
2028 this_alternative = reg_class_subunion[this_alternative][cl];
2029 IOR_HARD_REG_SET (this_alternative_set,
2030 reg_class_contents[cl]);
2031 if (costly_p)
2033 this_costly_alternative
2034 = reg_class_subunion[this_costly_alternative][cl];
2035 IOR_HARD_REG_SET (this_costly_alternative_set,
2036 reg_class_contents[cl]);
2038 if (mode == BLKmode)
2039 break;
2040 winreg = true;
2041 if (REG_P (op))
2043 if (hard_regno[nop] >= 0
2044 && in_hard_reg_set_p (this_alternative_set,
2045 mode, hard_regno[nop]))
2046 win = true;
2047 else if (hard_regno[nop] < 0
2048 && in_class_p (op, this_alternative, NULL))
2049 win = true;
2051 break;
2053 if (c != ' ' && c != '\t')
2054 costly_p = c == '*';
2056 while ((p += len), c);
2058 scratch_p = (operand_reg[nop] != NULL_RTX
2059 && lra_former_scratch_p (REGNO (operand_reg[nop])));
2060 /* Record which operands fit this alternative. */
2061 if (win)
2063 this_alternative_win = true;
2064 if (operand_reg[nop] != NULL_RTX)
2066 if (hard_regno[nop] >= 0)
2068 if (in_hard_reg_set_p (this_costly_alternative_set,
2069 mode, hard_regno[nop]))
2071 if (lra_dump_file != NULL)
2072 fprintf (lra_dump_file,
2073 " %d Costly set: reject++\n",
2074 nop);
2075 reject++;
2078 else
2080 /* Prefer won reg to spilled pseudo under other
2081 equal conditions for possibe inheritance. */
2082 if (! scratch_p)
2084 if (lra_dump_file != NULL)
2085 fprintf
2086 (lra_dump_file,
2087 " %d Non pseudo reload: reject++\n",
2088 nop);
2089 reject++;
2091 if (in_class_p (operand_reg[nop],
2092 this_costly_alternative, NULL))
2094 if (lra_dump_file != NULL)
2095 fprintf
2096 (lra_dump_file,
2097 " %d Non pseudo costly reload:"
2098 " reject++\n",
2099 nop);
2100 reject++;
2103 /* We simulate the behaviour of old reload here.
2104 Although scratches need hard registers and it
2105 might result in spilling other pseudos, no reload
2106 insns are generated for the scratches. So it
2107 might cost something but probably less than old
2108 reload pass believes. */
2109 if (scratch_p)
2111 if (lra_dump_file != NULL)
2112 fprintf (lra_dump_file,
2113 " %d Scratch win: reject+=2\n",
2114 nop);
2115 reject += 2;
2119 else if (did_match)
2120 this_alternative_match_win = true;
2121 else
2123 int const_to_mem = 0;
2124 bool no_regs_p;
2126 reject += op_reject;
2127 /* Never do output reload of stack pointer. It makes
2128 impossible to do elimination when SP is changed in
2129 RTL. */
2130 if (op == stack_pointer_rtx && ! frame_pointer_needed
2131 && curr_static_id->operand[nop].type != OP_IN)
2132 goto fail;
2134 /* If this alternative asks for a specific reg class, see if there
2135 is at least one allocatable register in that class. */
2136 no_regs_p
2137 = (this_alternative == NO_REGS
2138 || (hard_reg_set_subset_p
2139 (reg_class_contents[this_alternative],
2140 lra_no_alloc_regs)));
2142 /* For asms, verify that the class for this alternative is possible
2143 for the mode that is specified. */
2144 if (!no_regs_p && INSN_CODE (curr_insn) < 0)
2146 int i;
2147 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
2148 if (HARD_REGNO_MODE_OK (i, mode)
2149 && in_hard_reg_set_p (reg_class_contents[this_alternative],
2150 mode, i))
2151 break;
2152 if (i == FIRST_PSEUDO_REGISTER)
2153 winreg = false;
2156 /* If this operand accepts a register, and if the
2157 register class has at least one allocatable register,
2158 then this operand can be reloaded. */
2159 if (winreg && !no_regs_p)
2160 badop = false;
2162 if (badop)
2164 if (lra_dump_file != NULL)
2165 fprintf (lra_dump_file,
2166 " alt=%d: Bad operand -- refuse\n",
2167 nalt);
2168 goto fail;
2171 /* If not assigned pseudo has a class which a subset of
2172 required reg class, it is a less costly alternative
2173 as the pseudo still can get a hard reg of necessary
2174 class. */
2175 if (! no_regs_p && REG_P (op) && hard_regno[nop] < 0
2176 && (cl = get_reg_class (REGNO (op))) != NO_REGS
2177 && ira_class_subset_p[this_alternative][cl])
2179 if (lra_dump_file != NULL)
2180 fprintf
2181 (lra_dump_file,
2182 " %d Super set class reg: reject-=3\n", nop);
2183 reject -= 3;
2186 this_alternative_offmemok = offmemok;
2187 if (this_costly_alternative != NO_REGS)
2189 if (lra_dump_file != NULL)
2190 fprintf (lra_dump_file,
2191 " %d Costly loser: reject++\n", nop);
2192 reject++;
2194 /* If the operand is dying, has a matching constraint,
2195 and satisfies constraints of the matched operand
2196 which failed to satisfy the own constraints, most probably
2197 the reload for this operand will be gone. */
2198 if (this_alternative_matches >= 0
2199 && !curr_alt_win[this_alternative_matches]
2200 && REG_P (op)
2201 && find_regno_note (curr_insn, REG_DEAD, REGNO (op))
2202 && (hard_regno[nop] >= 0
2203 ? in_hard_reg_set_p (this_alternative_set,
2204 mode, hard_regno[nop])
2205 : in_class_p (op, this_alternative, NULL)))
2207 if (lra_dump_file != NULL)
2208 fprintf
2209 (lra_dump_file,
2210 " %d Dying matched operand reload: reject++\n",
2211 nop);
2212 reject++;
2214 else
2216 /* Strict_low_part requires to reload the register
2217 not the sub-register. In this case we should
2218 check that a final reload hard reg can hold the
2219 value mode. */
2220 if (curr_static_id->operand[nop].strict_low
2221 && REG_P (op)
2222 && hard_regno[nop] < 0
2223 && GET_CODE (*curr_id->operand_loc[nop]) == SUBREG
2224 && ira_class_hard_regs_num[this_alternative] > 0
2225 && ! HARD_REGNO_MODE_OK (ira_class_hard_regs
2226 [this_alternative][0],
2227 GET_MODE
2228 (*curr_id->operand_loc[nop])))
2230 if (lra_dump_file != NULL)
2231 fprintf
2232 (lra_dump_file,
2233 " alt=%d: Strict low subreg reload -- refuse\n",
2234 nalt);
2235 goto fail;
2237 losers++;
2239 if (operand_reg[nop] != NULL_RTX
2240 /* Output operands and matched input operands are
2241 not inherited. The following conditions do not
2242 exactly describe the previous statement but they
2243 are pretty close. */
2244 && curr_static_id->operand[nop].type != OP_OUT
2245 && (this_alternative_matches < 0
2246 || curr_static_id->operand[nop].type != OP_IN))
2248 int last_reload = (lra_reg_info[ORIGINAL_REGNO
2249 (operand_reg[nop])]
2250 .last_reload);
2252 /* The value of reload_sum has sense only if we
2253 process insns in their order. It happens only on
2254 the first constraints sub-pass when we do most of
2255 reload work. */
2256 if (lra_constraint_iter == 1 && last_reload > bb_reload_num)
2257 reload_sum += last_reload - bb_reload_num;
2259 /* If this is a constant that is reloaded into the
2260 desired class by copying it to memory first, count
2261 that as another reload. This is consistent with
2262 other code and is required to avoid choosing another
2263 alternative when the constant is moved into memory.
2264 Note that the test here is precisely the same as in
2265 the code below that calls force_const_mem. */
2266 if (CONST_POOL_OK_P (mode, op)
2267 && ((targetm.preferred_reload_class
2268 (op, this_alternative) == NO_REGS)
2269 || no_input_reloads_p))
2271 const_to_mem = 1;
2272 if (! no_regs_p)
2273 losers++;
2276 /* Alternative loses if it requires a type of reload not
2277 permitted for this insn. We can always reload
2278 objects with a REG_UNUSED note. */
2279 if ((curr_static_id->operand[nop].type != OP_IN
2280 && no_output_reloads_p
2281 && ! find_reg_note (curr_insn, REG_UNUSED, op))
2282 || (curr_static_id->operand[nop].type != OP_OUT
2283 && no_input_reloads_p && ! const_to_mem)
2284 || (this_alternative_matches >= 0
2285 && (no_input_reloads_p
2286 || (no_output_reloads_p
2287 && (curr_static_id->operand
2288 [this_alternative_matches].type != OP_IN)
2289 && ! find_reg_note (curr_insn, REG_UNUSED,
2290 no_subreg_reg_operand
2291 [this_alternative_matches])))))
2293 if (lra_dump_file != NULL)
2294 fprintf
2295 (lra_dump_file,
2296 " alt=%d: No input/otput reload -- refuse\n",
2297 nalt);
2298 goto fail;
2301 /* Alternative loses if it required class pseudo can not
2302 hold value of required mode. Such insns can be
2303 described by insn definitions with mode iterators. */
2304 if (GET_MODE (*curr_id->operand_loc[nop]) != VOIDmode
2305 && ! hard_reg_set_empty_p (this_alternative_set)
2306 /* It is common practice for constraints to use a
2307 class which does not have actually enough regs to
2308 hold the value (e.g. x86 AREG for mode requiring
2309 more one general reg). Therefore we have 2
2310 conditions to check that the reload pseudo can
2311 not hold the mode value. */
2312 && ! HARD_REGNO_MODE_OK (ira_class_hard_regs
2313 [this_alternative][0],
2314 GET_MODE (*curr_id->operand_loc[nop])))
2316 HARD_REG_SET temp;
2318 COPY_HARD_REG_SET (temp, this_alternative_set);
2319 AND_COMPL_HARD_REG_SET (temp, lra_no_alloc_regs);
2320 /* The above condition is not enough as the first
2321 reg in ira_class_hard_regs can be not aligned for
2322 multi-words mode values. */
2323 if (hard_reg_set_subset_p (temp,
2324 ira_prohibited_class_mode_regs
2325 [this_alternative]
2326 [GET_MODE (*curr_id->operand_loc[nop])]))
2328 if (lra_dump_file != NULL)
2329 fprintf
2330 (lra_dump_file,
2331 " alt=%d: reload pseudo for op %d "
2332 " can not hold the mode value -- refuse\n",
2333 nalt, nop);
2334 goto fail;
2338 /* Check strong discouragement of reload of non-constant
2339 into class THIS_ALTERNATIVE. */
2340 if (! CONSTANT_P (op) && ! no_regs_p
2341 && (targetm.preferred_reload_class
2342 (op, this_alternative) == NO_REGS
2343 || (curr_static_id->operand[nop].type == OP_OUT
2344 && (targetm.preferred_output_reload_class
2345 (op, this_alternative) == NO_REGS))))
2347 if (lra_dump_file != NULL)
2348 fprintf (lra_dump_file,
2349 " %d Non-prefered reload: reject+=%d\n",
2350 nop, LRA_MAX_REJECT);
2351 reject += LRA_MAX_REJECT;
2354 if (! (MEM_P (op) && offmemok)
2355 && ! (const_to_mem && constmemok))
2357 /* We prefer to reload pseudos over reloading other
2358 things, since such reloads may be able to be
2359 eliminated later. So bump REJECT in other cases.
2360 Don't do this in the case where we are forcing a
2361 constant into memory and it will then win since
2362 we don't want to have a different alternative
2363 match then. */
2364 if (! (REG_P (op) && REGNO (op) >= FIRST_PSEUDO_REGISTER))
2366 if (lra_dump_file != NULL)
2367 fprintf
2368 (lra_dump_file,
2369 " %d Non-pseudo reload: reject+=2\n",
2370 nop);
2371 reject += 2;
2374 if (! no_regs_p)
2375 reload_nregs
2376 += ira_reg_class_max_nregs[this_alternative][mode];
2378 if (SMALL_REGISTER_CLASS_P (this_alternative))
2380 if (lra_dump_file != NULL)
2381 fprintf
2382 (lra_dump_file,
2383 " %d Small class reload: reject+=%d\n",
2384 nop, LRA_LOSER_COST_FACTOR / 2);
2385 reject += LRA_LOSER_COST_FACTOR / 2;
2389 /* We are trying to spill pseudo into memory. It is
2390 usually more costly than moving to a hard register
2391 although it might takes the same number of
2392 reloads. */
2393 if (no_regs_p && REG_P (op) && hard_regno[nop] >= 0)
2395 if (lra_dump_file != NULL)
2396 fprintf
2397 (lra_dump_file,
2398 " %d Spill pseudo into memory: reject+=3\n",
2399 nop);
2400 reject += 3;
2401 if (VECTOR_MODE_P (mode))
2403 /* Spilling vectors into memory is usually more
2404 costly as they contain big values. */
2405 if (lra_dump_file != NULL)
2406 fprintf
2407 (lra_dump_file,
2408 " %d Spill vector pseudo: reject+=2\n",
2409 nop);
2410 reject += 2;
2414 #ifdef SECONDARY_MEMORY_NEEDED
2415 /* If reload requires moving value through secondary
2416 memory, it will need one more insn at least. */
2417 if (this_alternative != NO_REGS
2418 && REG_P (op) && (cl = get_reg_class (REGNO (op))) != NO_REGS
2419 && ((curr_static_id->operand[nop].type != OP_OUT
2420 && SECONDARY_MEMORY_NEEDED (cl, this_alternative,
2421 GET_MODE (op)))
2422 || (curr_static_id->operand[nop].type != OP_IN
2423 && SECONDARY_MEMORY_NEEDED (this_alternative, cl,
2424 GET_MODE (op)))))
2425 losers++;
2426 #endif
2427 /* Input reloads can be inherited more often than output
2428 reloads can be removed, so penalize output
2429 reloads. */
2430 if (!REG_P (op) || curr_static_id->operand[nop].type != OP_IN)
2432 if (lra_dump_file != NULL)
2433 fprintf
2434 (lra_dump_file,
2435 " %d Non input pseudo reload: reject++\n",
2436 nop);
2437 reject++;
2441 if (early_clobber_p && ! scratch_p)
2443 if (lra_dump_file != NULL)
2444 fprintf (lra_dump_file,
2445 " %d Early clobber: reject++\n", nop);
2446 reject++;
2448 /* ??? We check early clobbers after processing all operands
2449 (see loop below) and there we update the costs more.
2450 Should we update the cost (may be approximately) here
2451 because of early clobber register reloads or it is a rare
2452 or non-important thing to be worth to do it. */
2453 overall = losers * LRA_LOSER_COST_FACTOR + reject;
2454 if ((best_losers == 0 || losers != 0) && best_overall < overall)
2456 if (lra_dump_file != NULL)
2457 fprintf (lra_dump_file,
2458 " alt=%d,overall=%d,losers=%d -- refuse\n",
2459 nalt, overall, losers);
2460 goto fail;
2463 curr_alt[nop] = this_alternative;
2464 COPY_HARD_REG_SET (curr_alt_set[nop], this_alternative_set);
2465 curr_alt_win[nop] = this_alternative_win;
2466 curr_alt_match_win[nop] = this_alternative_match_win;
2467 curr_alt_offmemok[nop] = this_alternative_offmemok;
2468 curr_alt_matches[nop] = this_alternative_matches;
2470 if (this_alternative_matches >= 0
2471 && !did_match && !this_alternative_win)
2472 curr_alt_win[this_alternative_matches] = false;
2474 if (early_clobber_p && operand_reg[nop] != NULL_RTX)
2475 early_clobbered_nops[early_clobbered_regs_num++] = nop;
2477 if (curr_insn_set != NULL_RTX && n_operands == 2
2478 /* Prevent processing non-move insns. */
2479 && (GET_CODE (SET_SRC (curr_insn_set)) == SUBREG
2480 || SET_SRC (curr_insn_set) == no_subreg_reg_operand[1])
2481 && ((! curr_alt_win[0] && ! curr_alt_win[1]
2482 && REG_P (no_subreg_reg_operand[0])
2483 && REG_P (no_subreg_reg_operand[1])
2484 && (reg_in_class_p (no_subreg_reg_operand[0], curr_alt[1])
2485 || reg_in_class_p (no_subreg_reg_operand[1], curr_alt[0])))
2486 || (! curr_alt_win[0] && curr_alt_win[1]
2487 && REG_P (no_subreg_reg_operand[1])
2488 && reg_in_class_p (no_subreg_reg_operand[1], curr_alt[0]))
2489 || (curr_alt_win[0] && ! curr_alt_win[1]
2490 && REG_P (no_subreg_reg_operand[0])
2491 && reg_in_class_p (no_subreg_reg_operand[0], curr_alt[1])
2492 && (! CONST_POOL_OK_P (curr_operand_mode[1],
2493 no_subreg_reg_operand[1])
2494 || (targetm.preferred_reload_class
2495 (no_subreg_reg_operand[1],
2496 (enum reg_class) curr_alt[1]) != NO_REGS))
2497 /* If it is a result of recent elimination in move
2498 insn we can transform it into an add still by
2499 using this alternative. */
2500 && GET_CODE (no_subreg_reg_operand[1]) != PLUS)))
2502 /* We have a move insn and a new reload insn will be similar
2503 to the current insn. We should avoid such situation as it
2504 results in LRA cycling. */
2505 overall += LRA_MAX_REJECT;
2507 ok_p = true;
2508 curr_alt_dont_inherit_ops_num = 0;
2509 for (nop = 0; nop < early_clobbered_regs_num; nop++)
2511 int i, j, clobbered_hard_regno, first_conflict_j, last_conflict_j;
2512 HARD_REG_SET temp_set;
2514 i = early_clobbered_nops[nop];
2515 if ((! curr_alt_win[i] && ! curr_alt_match_win[i])
2516 || hard_regno[i] < 0)
2517 continue;
2518 lra_assert (operand_reg[i] != NULL_RTX);
2519 clobbered_hard_regno = hard_regno[i];
2520 CLEAR_HARD_REG_SET (temp_set);
2521 add_to_hard_reg_set (&temp_set, biggest_mode[i], clobbered_hard_regno);
2522 first_conflict_j = last_conflict_j = -1;
2523 for (j = 0; j < n_operands; j++)
2524 if (j == i
2525 /* We don't want process insides of match_operator and
2526 match_parallel because otherwise we would process
2527 their operands once again generating a wrong
2528 code. */
2529 || curr_static_id->operand[j].is_operator)
2530 continue;
2531 else if ((curr_alt_matches[j] == i && curr_alt_match_win[j])
2532 || (curr_alt_matches[i] == j && curr_alt_match_win[i]))
2533 continue;
2534 /* If we don't reload j-th operand, check conflicts. */
2535 else if ((curr_alt_win[j] || curr_alt_match_win[j])
2536 && uses_hard_regs_p (*curr_id->operand_loc[j], temp_set))
2538 if (first_conflict_j < 0)
2539 first_conflict_j = j;
2540 last_conflict_j = j;
2542 if (last_conflict_j < 0)
2543 continue;
2544 /* If earlyclobber operand conflicts with another
2545 non-matching operand which is actually the same register
2546 as the earlyclobber operand, it is better to reload the
2547 another operand as an operand matching the earlyclobber
2548 operand can be also the same. */
2549 if (first_conflict_j == last_conflict_j
2550 && operand_reg[last_conflict_j]
2551 != NULL_RTX && ! curr_alt_match_win[last_conflict_j]
2552 && REGNO (operand_reg[i]) == REGNO (operand_reg[last_conflict_j]))
2554 curr_alt_win[last_conflict_j] = false;
2555 curr_alt_dont_inherit_ops[curr_alt_dont_inherit_ops_num++]
2556 = last_conflict_j;
2557 losers++;
2558 /* Early clobber was already reflected in REJECT. */
2559 lra_assert (reject > 0);
2560 if (lra_dump_file != NULL)
2561 fprintf
2562 (lra_dump_file,
2563 " %d Conflict early clobber reload: reject--\n",
2565 reject--;
2566 overall += LRA_LOSER_COST_FACTOR - 1;
2568 else
2570 /* We need to reload early clobbered register and the
2571 matched registers. */
2572 for (j = 0; j < n_operands; j++)
2573 if (curr_alt_matches[j] == i)
2575 curr_alt_match_win[j] = false;
2576 losers++;
2577 overall += LRA_LOSER_COST_FACTOR;
2579 if (! curr_alt_match_win[i])
2580 curr_alt_dont_inherit_ops[curr_alt_dont_inherit_ops_num++] = i;
2581 else
2583 /* Remember pseudos used for match reloads are never
2584 inherited. */
2585 lra_assert (curr_alt_matches[i] >= 0);
2586 curr_alt_win[curr_alt_matches[i]] = false;
2588 curr_alt_win[i] = curr_alt_match_win[i] = false;
2589 losers++;
2590 /* Early clobber was already reflected in REJECT. */
2591 lra_assert (reject > 0);
2592 if (lra_dump_file != NULL)
2593 fprintf
2594 (lra_dump_file,
2595 " %d Matched conflict early clobber reloads:"
2596 "reject--\n",
2598 reject--;
2599 overall += LRA_LOSER_COST_FACTOR - 1;
2602 if (lra_dump_file != NULL)
2603 fprintf (lra_dump_file, " alt=%d,overall=%d,losers=%d,rld_nregs=%d\n",
2604 nalt, overall, losers, reload_nregs);
2606 /* If this alternative can be made to work by reloading, and it
2607 needs less reloading than the others checked so far, record
2608 it as the chosen goal for reloading. */
2609 if ((best_losers != 0 && losers == 0)
2610 || (((best_losers == 0 && losers == 0)
2611 || (best_losers != 0 && losers != 0))
2612 && (best_overall > overall
2613 || (best_overall == overall
2614 /* If the cost of the reloads is the same,
2615 prefer alternative which requires minimal
2616 number of reload regs. */
2617 && (reload_nregs < best_reload_nregs
2618 || (reload_nregs == best_reload_nregs
2619 && (best_reload_sum < reload_sum
2620 || (best_reload_sum == reload_sum
2621 && nalt < goal_alt_number))))))))
2623 for (nop = 0; nop < n_operands; nop++)
2625 goal_alt_win[nop] = curr_alt_win[nop];
2626 goal_alt_match_win[nop] = curr_alt_match_win[nop];
2627 goal_alt_matches[nop] = curr_alt_matches[nop];
2628 goal_alt[nop] = curr_alt[nop];
2629 goal_alt_offmemok[nop] = curr_alt_offmemok[nop];
2631 goal_alt_dont_inherit_ops_num = curr_alt_dont_inherit_ops_num;
2632 for (nop = 0; nop < curr_alt_dont_inherit_ops_num; nop++)
2633 goal_alt_dont_inherit_ops[nop] = curr_alt_dont_inherit_ops[nop];
2634 goal_alt_swapped = curr_swapped;
2635 best_overall = overall;
2636 best_losers = losers;
2637 best_reload_nregs = reload_nregs;
2638 best_reload_sum = reload_sum;
2639 goal_alt_number = nalt;
2641 if (losers == 0)
2642 /* Everything is satisfied. Do not process alternatives
2643 anymore. */
2644 break;
2645 fail:
2648 return ok_p;
2651 /* Make reload base reg from address AD. */
2652 static rtx
2653 base_to_reg (struct address_info *ad)
2655 enum reg_class cl;
2656 int code = -1;
2657 rtx new_inner = NULL_RTX;
2658 rtx new_reg = NULL_RTX;
2659 rtx_insn *insn;
2660 rtx_insn *last_insn = get_last_insn();
2662 lra_assert (ad->base == ad->base_term && ad->disp == ad->disp_term);
2663 cl = base_reg_class (ad->mode, ad->as, ad->base_outer_code,
2664 get_index_code (ad));
2665 new_reg = lra_create_new_reg (GET_MODE (*ad->base_term), NULL_RTX,
2666 cl, "base");
2667 new_inner = simplify_gen_binary (PLUS, GET_MODE (new_reg), new_reg,
2668 ad->disp_term == NULL
2669 ? gen_int_mode (0, ad->mode)
2670 : *ad->disp_term);
2671 if (!valid_address_p (ad->mode, new_inner, ad->as))
2672 return NULL_RTX;
2673 insn = emit_insn (gen_rtx_SET (ad->mode, new_reg, *ad->base_term));
2674 code = recog_memoized (insn);
2675 if (code < 0)
2677 delete_insns_since (last_insn);
2678 return NULL_RTX;
2681 return new_inner;
2684 /* Make reload base reg + disp from address AD. Return the new pseudo. */
2685 static rtx
2686 base_plus_disp_to_reg (struct address_info *ad)
2688 enum reg_class cl;
2689 rtx new_reg;
2691 lra_assert (ad->base == ad->base_term && ad->disp == ad->disp_term);
2692 cl = base_reg_class (ad->mode, ad->as, ad->base_outer_code,
2693 get_index_code (ad));
2694 new_reg = lra_create_new_reg (GET_MODE (*ad->base_term), NULL_RTX,
2695 cl, "base + disp");
2696 lra_emit_add (new_reg, *ad->base_term, *ad->disp_term);
2697 return new_reg;
2700 /* Make reload of index part of address AD. Return the new
2701 pseudo. */
2702 static rtx
2703 index_part_to_reg (struct address_info *ad)
2705 rtx new_reg;
2707 new_reg = lra_create_new_reg (GET_MODE (*ad->index), NULL_RTX,
2708 INDEX_REG_CLASS, "index term");
2709 expand_mult (GET_MODE (*ad->index), *ad->index_term,
2710 GEN_INT (get_index_scale (ad)), new_reg, 1);
2711 return new_reg;
2714 /* Return true if we can add a displacement to address AD, even if that
2715 makes the address invalid. The fix-up code requires any new address
2716 to be the sum of the BASE_TERM, INDEX and DISP_TERM fields. */
2717 static bool
2718 can_add_disp_p (struct address_info *ad)
2720 return (!ad->autoinc_p
2721 && ad->segment == NULL
2722 && ad->base == ad->base_term
2723 && ad->disp == ad->disp_term);
2726 /* Make equiv substitution in address AD. Return true if a substitution
2727 was made. */
2728 static bool
2729 equiv_address_substitution (struct address_info *ad)
2731 rtx base_reg, new_base_reg, index_reg, new_index_reg, *base_term, *index_term;
2732 HOST_WIDE_INT disp, scale;
2733 bool change_p;
2735 base_term = strip_subreg (ad->base_term);
2736 if (base_term == NULL)
2737 base_reg = new_base_reg = NULL_RTX;
2738 else
2740 base_reg = *base_term;
2741 new_base_reg = get_equiv_with_elimination (base_reg, curr_insn);
2743 index_term = strip_subreg (ad->index_term);
2744 if (index_term == NULL)
2745 index_reg = new_index_reg = NULL_RTX;
2746 else
2748 index_reg = *index_term;
2749 new_index_reg = get_equiv_with_elimination (index_reg, curr_insn);
2751 if (base_reg == new_base_reg && index_reg == new_index_reg)
2752 return false;
2753 disp = 0;
2754 change_p = false;
2755 if (lra_dump_file != NULL)
2757 fprintf (lra_dump_file, "Changing address in insn %d ",
2758 INSN_UID (curr_insn));
2759 dump_value_slim (lra_dump_file, *ad->outer, 1);
2761 if (base_reg != new_base_reg)
2763 if (REG_P (new_base_reg))
2765 *base_term = new_base_reg;
2766 change_p = true;
2768 else if (GET_CODE (new_base_reg) == PLUS
2769 && REG_P (XEXP (new_base_reg, 0))
2770 && CONST_INT_P (XEXP (new_base_reg, 1))
2771 && can_add_disp_p (ad))
2773 disp += INTVAL (XEXP (new_base_reg, 1));
2774 *base_term = XEXP (new_base_reg, 0);
2775 change_p = true;
2777 if (ad->base_term2 != NULL)
2778 *ad->base_term2 = *ad->base_term;
2780 if (index_reg != new_index_reg)
2782 if (REG_P (new_index_reg))
2784 *index_term = new_index_reg;
2785 change_p = true;
2787 else if (GET_CODE (new_index_reg) == PLUS
2788 && REG_P (XEXP (new_index_reg, 0))
2789 && CONST_INT_P (XEXP (new_index_reg, 1))
2790 && can_add_disp_p (ad)
2791 && (scale = get_index_scale (ad)))
2793 disp += INTVAL (XEXP (new_index_reg, 1)) * scale;
2794 *index_term = XEXP (new_index_reg, 0);
2795 change_p = true;
2798 if (disp != 0)
2800 if (ad->disp != NULL)
2801 *ad->disp = plus_constant (GET_MODE (*ad->inner), *ad->disp, disp);
2802 else
2804 *ad->inner = plus_constant (GET_MODE (*ad->inner), *ad->inner, disp);
2805 update_address (ad);
2807 change_p = true;
2809 if (lra_dump_file != NULL)
2811 if (! change_p)
2812 fprintf (lra_dump_file, " -- no change\n");
2813 else
2815 fprintf (lra_dump_file, " on equiv ");
2816 dump_value_slim (lra_dump_file, *ad->outer, 1);
2817 fprintf (lra_dump_file, "\n");
2820 return change_p;
2823 /* Major function to make reloads for an address in operand NOP or
2824 check its correctness (If CHECK_ONLY_P is true). The supported
2825 cases are:
2827 1) an address that existed before LRA started, at which point it
2828 must have been valid. These addresses are subject to elimination
2829 and may have become invalid due to the elimination offset being out
2830 of range.
2832 2) an address created by forcing a constant to memory
2833 (force_const_to_mem). The initial form of these addresses might
2834 not be valid, and it is this function's job to make them valid.
2836 3) a frame address formed from a register and a (possibly zero)
2837 constant offset. As above, these addresses might not be valid and
2838 this function must make them so.
2840 Add reloads to the lists *BEFORE and *AFTER. We might need to add
2841 reloads to *AFTER because of inc/dec, {pre, post} modify in the
2842 address. Return true for any RTL change.
2844 The function is a helper function which does not produce all
2845 transformations (when CHECK_ONLY_P is false) which can be
2846 necessary. It does just basic steps. To do all necessary
2847 transformations use function process_address. */
2848 static bool
2849 process_address_1 (int nop, bool check_only_p,
2850 rtx_insn **before, rtx_insn **after)
2852 struct address_info ad;
2853 rtx new_reg;
2854 rtx op = *curr_id->operand_loc[nop];
2855 const char *constraint = curr_static_id->operand[nop].constraint;
2856 enum constraint_num cn = lookup_constraint (constraint);
2857 bool change_p = false;
2859 if (insn_extra_address_constraint (cn))
2860 decompose_lea_address (&ad, curr_id->operand_loc[nop]);
2861 else if (MEM_P (op))
2862 decompose_mem_address (&ad, op);
2863 else if (GET_CODE (op) == SUBREG
2864 && MEM_P (SUBREG_REG (op)))
2865 decompose_mem_address (&ad, SUBREG_REG (op));
2866 else
2867 return false;
2868 /* If INDEX_REG_CLASS is assigned to base_term already and isn't to
2869 index_term, swap them so to avoid assigning INDEX_REG_CLASS to both
2870 when INDEX_REG_CLASS is a single register class. */
2871 if (ad.base_term != NULL
2872 && ad.index_term != NULL
2873 && ira_class_hard_regs_num[INDEX_REG_CLASS] == 1
2874 && REG_P (*ad.base_term)
2875 && REG_P (*ad.index_term)
2876 && in_class_p (*ad.base_term, INDEX_REG_CLASS, NULL)
2877 && ! in_class_p (*ad.index_term, INDEX_REG_CLASS, NULL))
2879 std::swap (ad.base, ad.index);
2880 std::swap (ad.base_term, ad.index_term);
2882 if (! check_only_p)
2883 change_p = equiv_address_substitution (&ad);
2884 if (ad.base_term != NULL
2885 && (process_addr_reg
2886 (ad.base_term, check_only_p, before,
2887 (ad.autoinc_p
2888 && !(REG_P (*ad.base_term)
2889 && find_regno_note (curr_insn, REG_DEAD,
2890 REGNO (*ad.base_term)) != NULL_RTX)
2891 ? after : NULL),
2892 base_reg_class (ad.mode, ad.as, ad.base_outer_code,
2893 get_index_code (&ad)))))
2895 change_p = true;
2896 if (ad.base_term2 != NULL)
2897 *ad.base_term2 = *ad.base_term;
2899 if (ad.index_term != NULL
2900 && process_addr_reg (ad.index_term, check_only_p,
2901 before, NULL, INDEX_REG_CLASS))
2902 change_p = true;
2904 /* Target hooks sometimes don't treat extra-constraint addresses as
2905 legitimate address_operands, so handle them specially. */
2906 if (insn_extra_address_constraint (cn)
2907 && satisfies_address_constraint_p (&ad, cn))
2908 return change_p;
2910 if (check_only_p)
2911 return change_p;
2913 /* There are three cases where the shape of *AD.INNER may now be invalid:
2915 1) the original address was valid, but either elimination or
2916 equiv_address_substitution was applied and that made
2917 the address invalid.
2919 2) the address is an invalid symbolic address created by
2920 force_const_to_mem.
2922 3) the address is a frame address with an invalid offset.
2924 4) the address is a frame address with an invalid base.
2926 All these cases involve a non-autoinc address, so there is no
2927 point revalidating other types. */
2928 if (ad.autoinc_p || valid_address_p (&ad))
2929 return change_p;
2931 /* Any index existed before LRA started, so we can assume that the
2932 presence and shape of the index is valid. */
2933 push_to_sequence (*before);
2934 lra_assert (ad.disp == ad.disp_term);
2935 if (ad.base == NULL)
2937 if (ad.index == NULL)
2939 int code = -1;
2940 enum reg_class cl = base_reg_class (ad.mode, ad.as,
2941 SCRATCH, SCRATCH);
2942 rtx addr = *ad.inner;
2944 new_reg = lra_create_new_reg (Pmode, NULL_RTX, cl, "addr");
2945 #ifdef HAVE_lo_sum
2947 rtx_insn *insn;
2948 rtx_insn *last = get_last_insn ();
2950 /* addr => lo_sum (new_base, addr), case (2) above. */
2951 insn = emit_insn (gen_rtx_SET
2952 (VOIDmode, new_reg,
2953 gen_rtx_HIGH (Pmode, copy_rtx (addr))));
2954 code = recog_memoized (insn);
2955 if (code >= 0)
2957 *ad.inner = gen_rtx_LO_SUM (Pmode, new_reg, addr);
2958 if (! valid_address_p (ad.mode, *ad.outer, ad.as))
2960 /* Try to put lo_sum into register. */
2961 insn = emit_insn (gen_rtx_SET
2962 (VOIDmode, new_reg,
2963 gen_rtx_LO_SUM (Pmode, new_reg, addr)));
2964 code = recog_memoized (insn);
2965 if (code >= 0)
2967 *ad.inner = new_reg;
2968 if (! valid_address_p (ad.mode, *ad.outer, ad.as))
2970 *ad.inner = addr;
2971 code = -1;
2977 if (code < 0)
2978 delete_insns_since (last);
2980 #endif
2981 if (code < 0)
2983 /* addr => new_base, case (2) above. */
2984 lra_emit_move (new_reg, addr);
2985 *ad.inner = new_reg;
2988 else
2990 /* index * scale + disp => new base + index * scale,
2991 case (1) above. */
2992 enum reg_class cl = base_reg_class (ad.mode, ad.as, PLUS,
2993 GET_CODE (*ad.index));
2995 lra_assert (INDEX_REG_CLASS != NO_REGS);
2996 new_reg = lra_create_new_reg (Pmode, NULL_RTX, cl, "disp");
2997 lra_emit_move (new_reg, *ad.disp);
2998 *ad.inner = simplify_gen_binary (PLUS, GET_MODE (new_reg),
2999 new_reg, *ad.index);
3002 else if (ad.index == NULL)
3004 int regno;
3005 enum reg_class cl;
3006 rtx set;
3007 rtx_insn *insns, *last_insn;
3008 /* Try to reload base into register only if the base is invalid
3009 for the address but with valid offset, case (4) above. */
3010 start_sequence ();
3011 new_reg = base_to_reg (&ad);
3013 /* base + disp => new base, cases (1) and (3) above. */
3014 /* Another option would be to reload the displacement into an
3015 index register. However, postreload has code to optimize
3016 address reloads that have the same base and different
3017 displacements, so reloading into an index register would
3018 not necessarily be a win. */
3019 if (new_reg == NULL_RTX)
3020 new_reg = base_plus_disp_to_reg (&ad);
3021 insns = get_insns ();
3022 last_insn = get_last_insn ();
3023 /* If we generated at least two insns, try last insn source as
3024 an address. If we succeed, we generate one less insn. */
3025 if (last_insn != insns && (set = single_set (last_insn)) != NULL_RTX
3026 && GET_CODE (SET_SRC (set)) == PLUS
3027 && REG_P (XEXP (SET_SRC (set), 0))
3028 && CONSTANT_P (XEXP (SET_SRC (set), 1)))
3030 *ad.inner = SET_SRC (set);
3031 if (valid_address_p (ad.mode, *ad.outer, ad.as))
3033 *ad.base_term = XEXP (SET_SRC (set), 0);
3034 *ad.disp_term = XEXP (SET_SRC (set), 1);
3035 cl = base_reg_class (ad.mode, ad.as, ad.base_outer_code,
3036 get_index_code (&ad));
3037 regno = REGNO (*ad.base_term);
3038 if (regno >= FIRST_PSEUDO_REGISTER
3039 && cl != lra_get_allocno_class (regno))
3040 lra_change_class (regno, cl, " Change to", true);
3041 new_reg = SET_SRC (set);
3042 delete_insns_since (PREV_INSN (last_insn));
3045 /* Try if target can split displacement into legitimite new disp
3046 and offset. If it's the case, we replace the last insn with
3047 insns for base + offset => new_reg and set new_reg + new disp
3048 to *ad.inner. */
3049 last_insn = get_last_insn ();
3050 if ((set = single_set (last_insn)) != NULL_RTX
3051 && GET_CODE (SET_SRC (set)) == PLUS
3052 && REG_P (XEXP (SET_SRC (set), 0))
3053 && REGNO (XEXP (SET_SRC (set), 0)) < FIRST_PSEUDO_REGISTER
3054 && CONST_INT_P (XEXP (SET_SRC (set), 1)))
3056 rtx addend, disp = XEXP (SET_SRC (set), 1);
3057 if (targetm.legitimize_address_displacement (&disp, &addend,
3058 ad.mode))
3060 rtx_insn *new_insns;
3061 start_sequence ();
3062 lra_emit_add (new_reg, XEXP (SET_SRC (set), 0), addend);
3063 new_insns = get_insns ();
3064 end_sequence ();
3065 new_reg = gen_rtx_PLUS (Pmode, new_reg, disp);
3066 delete_insns_since (PREV_INSN (last_insn));
3067 add_insn (new_insns);
3068 insns = get_insns ();
3071 end_sequence ();
3072 emit_insn (insns);
3073 *ad.inner = new_reg;
3075 else if (ad.disp_term != NULL)
3077 /* base + scale * index + disp => new base + scale * index,
3078 case (1) above. */
3079 new_reg = base_plus_disp_to_reg (&ad);
3080 *ad.inner = simplify_gen_binary (PLUS, GET_MODE (new_reg),
3081 new_reg, *ad.index);
3083 else if (get_index_scale (&ad) == 1)
3085 /* The last transformation to one reg will be made in
3086 curr_insn_transform function. */
3087 end_sequence ();
3088 return false;
3090 else
3092 /* base + scale * index => base + new_reg,
3093 case (1) above.
3094 Index part of address may become invalid. For example, we
3095 changed pseudo on the equivalent memory and a subreg of the
3096 pseudo onto the memory of different mode for which the scale is
3097 prohibitted. */
3098 new_reg = index_part_to_reg (&ad);
3099 *ad.inner = simplify_gen_binary (PLUS, GET_MODE (new_reg),
3100 *ad.base_term, new_reg);
3102 *before = get_insns ();
3103 end_sequence ();
3104 return true;
3107 /* If CHECK_ONLY_P is false, do address reloads until it is necessary.
3108 Use process_address_1 as a helper function. Return true for any
3109 RTL changes.
3111 If CHECK_ONLY_P is true, just check address correctness. Return
3112 false if the address correct. */
3113 static bool
3114 process_address (int nop, bool check_only_p,
3115 rtx_insn **before, rtx_insn **after)
3117 bool res = false;
3119 while (process_address_1 (nop, check_only_p, before, after))
3121 if (check_only_p)
3122 return true;
3123 res = true;
3125 return res;
3128 /* Emit insns to reload VALUE into a new register. VALUE is an
3129 auto-increment or auto-decrement RTX whose operand is a register or
3130 memory location; so reloading involves incrementing that location.
3131 IN is either identical to VALUE, or some cheaper place to reload
3132 value being incremented/decremented from.
3134 INC_AMOUNT is the number to increment or decrement by (always
3135 positive and ignored for POST_MODIFY/PRE_MODIFY).
3137 Return pseudo containing the result. */
3138 static rtx
3139 emit_inc (enum reg_class new_rclass, rtx in, rtx value, int inc_amount)
3141 /* REG or MEM to be copied and incremented. */
3142 rtx incloc = XEXP (value, 0);
3143 /* Nonzero if increment after copying. */
3144 int post = (GET_CODE (value) == POST_DEC || GET_CODE (value) == POST_INC
3145 || GET_CODE (value) == POST_MODIFY);
3146 rtx_insn *last;
3147 rtx inc;
3148 rtx_insn *add_insn;
3149 int code;
3150 rtx real_in = in == value ? incloc : in;
3151 rtx result;
3152 bool plus_p = true;
3154 if (GET_CODE (value) == PRE_MODIFY || GET_CODE (value) == POST_MODIFY)
3156 lra_assert (GET_CODE (XEXP (value, 1)) == PLUS
3157 || GET_CODE (XEXP (value, 1)) == MINUS);
3158 lra_assert (rtx_equal_p (XEXP (XEXP (value, 1), 0), XEXP (value, 0)));
3159 plus_p = GET_CODE (XEXP (value, 1)) == PLUS;
3160 inc = XEXP (XEXP (value, 1), 1);
3162 else
3164 if (GET_CODE (value) == PRE_DEC || GET_CODE (value) == POST_DEC)
3165 inc_amount = -inc_amount;
3167 inc = GEN_INT (inc_amount);
3170 if (! post && REG_P (incloc))
3171 result = incloc;
3172 else
3173 result = lra_create_new_reg (GET_MODE (value), value, new_rclass,
3174 "INC/DEC result");
3176 if (real_in != result)
3178 /* First copy the location to the result register. */
3179 lra_assert (REG_P (result));
3180 emit_insn (gen_move_insn (result, real_in));
3183 /* We suppose that there are insns to add/sub with the constant
3184 increment permitted in {PRE/POST)_{DEC/INC/MODIFY}. At least the
3185 old reload worked with this assumption. If the assumption
3186 becomes wrong, we should use approach in function
3187 base_plus_disp_to_reg. */
3188 if (in == value)
3190 /* See if we can directly increment INCLOC. */
3191 last = get_last_insn ();
3192 add_insn = emit_insn (plus_p
3193 ? gen_add2_insn (incloc, inc)
3194 : gen_sub2_insn (incloc, inc));
3196 code = recog_memoized (add_insn);
3197 if (code >= 0)
3199 if (! post && result != incloc)
3200 emit_insn (gen_move_insn (result, incloc));
3201 return result;
3203 delete_insns_since (last);
3206 /* If couldn't do the increment directly, must increment in RESULT.
3207 The way we do this depends on whether this is pre- or
3208 post-increment. For pre-increment, copy INCLOC to the reload
3209 register, increment it there, then save back. */
3210 if (! post)
3212 if (real_in != result)
3213 emit_insn (gen_move_insn (result, real_in));
3214 if (plus_p)
3215 emit_insn (gen_add2_insn (result, inc));
3216 else
3217 emit_insn (gen_sub2_insn (result, inc));
3218 if (result != incloc)
3219 emit_insn (gen_move_insn (incloc, result));
3221 else
3223 /* Post-increment.
3225 Because this might be a jump insn or a compare, and because
3226 RESULT may not be available after the insn in an input
3227 reload, we must do the incrementing before the insn being
3228 reloaded for.
3230 We have already copied IN to RESULT. Increment the copy in
3231 RESULT, save that back, then decrement RESULT so it has
3232 the original value. */
3233 if (plus_p)
3234 emit_insn (gen_add2_insn (result, inc));
3235 else
3236 emit_insn (gen_sub2_insn (result, inc));
3237 emit_insn (gen_move_insn (incloc, result));
3238 /* Restore non-modified value for the result. We prefer this
3239 way because it does not require an additional hard
3240 register. */
3241 if (plus_p)
3243 if (CONST_INT_P (inc))
3244 emit_insn (gen_add2_insn (result,
3245 gen_int_mode (-INTVAL (inc),
3246 GET_MODE (result))));
3247 else
3248 emit_insn (gen_sub2_insn (result, inc));
3250 else
3251 emit_insn (gen_add2_insn (result, inc));
3253 return result;
3256 /* Return true if the current move insn does not need processing as we
3257 already know that it satisfies its constraints. */
3258 static bool
3259 simple_move_p (void)
3261 rtx dest, src;
3262 enum reg_class dclass, sclass;
3264 lra_assert (curr_insn_set != NULL_RTX);
3265 dest = SET_DEST (curr_insn_set);
3266 src = SET_SRC (curr_insn_set);
3267 return ((dclass = get_op_class (dest)) != NO_REGS
3268 && (sclass = get_op_class (src)) != NO_REGS
3269 /* The backend guarantees that register moves of cost 2
3270 never need reloads. */
3271 && targetm.register_move_cost (GET_MODE (src), sclass, dclass) == 2);
3274 /* Swap operands NOP and NOP + 1. */
3275 static inline void
3276 swap_operands (int nop)
3278 machine_mode mode = curr_operand_mode[nop];
3279 curr_operand_mode[nop] = curr_operand_mode[nop + 1];
3280 curr_operand_mode[nop + 1] = mode;
3281 rtx x = *curr_id->operand_loc[nop];
3282 *curr_id->operand_loc[nop] = *curr_id->operand_loc[nop + 1];
3283 *curr_id->operand_loc[nop + 1] = x;
3284 /* Swap the duplicates too. */
3285 lra_update_dup (curr_id, nop);
3286 lra_update_dup (curr_id, nop + 1);
3289 /* Main entry point of the constraint code: search the body of the
3290 current insn to choose the best alternative. It is mimicking insn
3291 alternative cost calculation model of former reload pass. That is
3292 because machine descriptions were written to use this model. This
3293 model can be changed in future. Make commutative operand exchange
3294 if it is chosen.
3296 if CHECK_ONLY_P is false, do RTL changes to satisfy the
3297 constraints. Return true if any change happened during function
3298 call.
3300 If CHECK_ONLY_P is true then don't do any transformation. Just
3301 check that the insn satisfies all constraints. If the insn does
3302 not satisfy any constraint, return true. */
3303 static bool
3304 curr_insn_transform (bool check_only_p)
3306 int i, j, k;
3307 int n_operands;
3308 int n_alternatives;
3309 int commutative;
3310 signed char goal_alt_matched[MAX_RECOG_OPERANDS][MAX_RECOG_OPERANDS];
3311 signed char match_inputs[MAX_RECOG_OPERANDS + 1];
3312 rtx_insn *before, *after;
3313 bool alt_p = false;
3314 /* Flag that the insn has been changed through a transformation. */
3315 bool change_p;
3316 bool sec_mem_p;
3317 #ifdef SECONDARY_MEMORY_NEEDED
3318 bool use_sec_mem_p;
3319 #endif
3320 int max_regno_before;
3321 int reused_alternative_num;
3323 curr_insn_set = single_set (curr_insn);
3324 if (curr_insn_set != NULL_RTX && simple_move_p ())
3325 return false;
3327 no_input_reloads_p = no_output_reloads_p = false;
3328 goal_alt_number = -1;
3329 change_p = sec_mem_p = false;
3330 /* JUMP_INSNs and CALL_INSNs are not allowed to have any output
3331 reloads; neither are insns that SET cc0. Insns that use CC0 are
3332 not allowed to have any input reloads. */
3333 if (JUMP_P (curr_insn) || CALL_P (curr_insn))
3334 no_output_reloads_p = true;
3336 #ifdef HAVE_cc0
3337 if (reg_referenced_p (cc0_rtx, PATTERN (curr_insn)))
3338 no_input_reloads_p = true;
3339 if (reg_set_p (cc0_rtx, PATTERN (curr_insn)))
3340 no_output_reloads_p = true;
3341 #endif
3343 n_operands = curr_static_id->n_operands;
3344 n_alternatives = curr_static_id->n_alternatives;
3346 /* Just return "no reloads" if insn has no operands with
3347 constraints. */
3348 if (n_operands == 0 || n_alternatives == 0)
3349 return false;
3351 max_regno_before = max_reg_num ();
3353 for (i = 0; i < n_operands; i++)
3355 goal_alt_matched[i][0] = -1;
3356 goal_alt_matches[i] = -1;
3359 commutative = curr_static_id->commutative;
3361 /* Now see what we need for pseudos that didn't get hard regs or got
3362 the wrong kind of hard reg. For this, we must consider all the
3363 operands together against the register constraints. */
3365 best_losers = best_overall = INT_MAX;
3366 best_reload_sum = 0;
3368 curr_swapped = false;
3369 goal_alt_swapped = false;
3371 if (! check_only_p)
3372 /* Make equivalence substitution and memory subreg elimination
3373 before address processing because an address legitimacy can
3374 depend on memory mode. */
3375 for (i = 0; i < n_operands; i++)
3377 rtx op = *curr_id->operand_loc[i];
3378 rtx subst, old = op;
3379 bool op_change_p = false;
3381 if (GET_CODE (old) == SUBREG)
3382 old = SUBREG_REG (old);
3383 subst = get_equiv_with_elimination (old, curr_insn);
3384 if (subst != old)
3386 subst = copy_rtx (subst);
3387 lra_assert (REG_P (old));
3388 if (GET_CODE (op) == SUBREG)
3389 SUBREG_REG (op) = subst;
3390 else
3391 *curr_id->operand_loc[i] = subst;
3392 if (lra_dump_file != NULL)
3394 fprintf (lra_dump_file,
3395 "Changing pseudo %d in operand %i of insn %u on equiv ",
3396 REGNO (old), i, INSN_UID (curr_insn));
3397 dump_value_slim (lra_dump_file, subst, 1);
3398 fprintf (lra_dump_file, "\n");
3400 op_change_p = change_p = true;
3402 if (simplify_operand_subreg (i, GET_MODE (old)) || op_change_p)
3404 change_p = true;
3405 lra_update_dup (curr_id, i);
3409 /* Reload address registers and displacements. We do it before
3410 finding an alternative because of memory constraints. */
3411 before = after = NULL;
3412 for (i = 0; i < n_operands; i++)
3413 if (! curr_static_id->operand[i].is_operator
3414 && process_address (i, check_only_p, &before, &after))
3416 if (check_only_p)
3417 return true;
3418 change_p = true;
3419 lra_update_dup (curr_id, i);
3422 if (change_p)
3423 /* If we've changed the instruction then any alternative that
3424 we chose previously may no longer be valid. */
3425 lra_set_used_insn_alternative (curr_insn, -1);
3427 if (! check_only_p && curr_insn_set != NULL_RTX
3428 && check_and_process_move (&change_p, &sec_mem_p))
3429 return change_p;
3431 try_swapped:
3433 reused_alternative_num = check_only_p ? -1 : curr_id->used_insn_alternative;
3434 if (lra_dump_file != NULL && reused_alternative_num >= 0)
3435 fprintf (lra_dump_file, "Reusing alternative %d for insn #%u\n",
3436 reused_alternative_num, INSN_UID (curr_insn));
3438 if (process_alt_operands (reused_alternative_num))
3439 alt_p = true;
3441 if (check_only_p)
3442 return ! alt_p || best_losers != 0;
3444 /* If insn is commutative (it's safe to exchange a certain pair of
3445 operands) then we need to try each alternative twice, the second
3446 time matching those two operands as if we had exchanged them. To
3447 do this, really exchange them in operands.
3449 If we have just tried the alternatives the second time, return
3450 operands to normal and drop through. */
3452 if (reused_alternative_num < 0 && commutative >= 0)
3454 curr_swapped = !curr_swapped;
3455 if (curr_swapped)
3457 swap_operands (commutative);
3458 goto try_swapped;
3460 else
3461 swap_operands (commutative);
3464 if (! alt_p && ! sec_mem_p)
3466 /* No alternative works with reloads?? */
3467 if (INSN_CODE (curr_insn) >= 0)
3468 fatal_insn ("unable to generate reloads for:", curr_insn);
3469 error_for_asm (curr_insn,
3470 "inconsistent operand constraints in an %<asm%>");
3471 /* Avoid further trouble with this insn. */
3472 PATTERN (curr_insn) = gen_rtx_USE (VOIDmode, const0_rtx);
3473 lra_invalidate_insn_data (curr_insn);
3474 return true;
3477 /* If the best alternative is with operands 1 and 2 swapped, swap
3478 them. Update the operand numbers of any reloads already
3479 pushed. */
3481 if (goal_alt_swapped)
3483 if (lra_dump_file != NULL)
3484 fprintf (lra_dump_file, " Commutative operand exchange in insn %u\n",
3485 INSN_UID (curr_insn));
3487 /* Swap the duplicates too. */
3488 swap_operands (commutative);
3489 change_p = true;
3492 #ifdef SECONDARY_MEMORY_NEEDED
3493 /* Some target macros SECONDARY_MEMORY_NEEDED (e.g. x86) are defined
3494 too conservatively. So we use the secondary memory only if there
3495 is no any alternative without reloads. */
3496 use_sec_mem_p = false;
3497 if (! alt_p)
3498 use_sec_mem_p = true;
3499 else if (sec_mem_p)
3501 for (i = 0; i < n_operands; i++)
3502 if (! goal_alt_win[i] && ! goal_alt_match_win[i])
3503 break;
3504 use_sec_mem_p = i < n_operands;
3507 if (use_sec_mem_p)
3509 rtx new_reg, src, dest, rld;
3510 machine_mode sec_mode, rld_mode;
3512 lra_assert (sec_mem_p);
3513 lra_assert (curr_static_id->operand[0].type == OP_OUT
3514 && curr_static_id->operand[1].type == OP_IN);
3515 dest = *curr_id->operand_loc[0];
3516 src = *curr_id->operand_loc[1];
3517 rld = (GET_MODE_SIZE (GET_MODE (dest)) <= GET_MODE_SIZE (GET_MODE (src))
3518 ? dest : src);
3519 rld_mode = GET_MODE (rld);
3520 #ifdef SECONDARY_MEMORY_NEEDED_MODE
3521 sec_mode = SECONDARY_MEMORY_NEEDED_MODE (rld_mode);
3522 #else
3523 sec_mode = rld_mode;
3524 #endif
3525 new_reg = lra_create_new_reg (sec_mode, NULL_RTX,
3526 NO_REGS, "secondary");
3527 /* If the mode is changed, it should be wider. */
3528 lra_assert (GET_MODE_SIZE (sec_mode) >= GET_MODE_SIZE (rld_mode));
3529 if (sec_mode != rld_mode)
3531 /* If the target says specifically to use another mode for
3532 secondary memory moves we can not reuse the original
3533 insn. */
3534 after = emit_spill_move (false, new_reg, dest);
3535 lra_process_new_insns (curr_insn, NULL, after,
3536 "Inserting the sec. move");
3537 /* We may have non null BEFORE here (e.g. after address
3538 processing. */
3539 push_to_sequence (before);
3540 before = emit_spill_move (true, new_reg, src);
3541 emit_insn (before);
3542 before = get_insns ();
3543 end_sequence ();
3544 lra_process_new_insns (curr_insn, before, NULL, "Changing on");
3545 lra_set_insn_deleted (curr_insn);
3547 else if (dest == rld)
3549 *curr_id->operand_loc[0] = new_reg;
3550 after = emit_spill_move (false, new_reg, dest);
3551 lra_process_new_insns (curr_insn, NULL, after,
3552 "Inserting the sec. move");
3554 else
3556 *curr_id->operand_loc[1] = new_reg;
3557 /* See comments above. */
3558 push_to_sequence (before);
3559 before = emit_spill_move (true, new_reg, src);
3560 emit_insn (before);
3561 before = get_insns ();
3562 end_sequence ();
3563 lra_process_new_insns (curr_insn, before, NULL,
3564 "Inserting the sec. move");
3566 lra_update_insn_regno_info (curr_insn);
3567 return true;
3569 #endif
3571 lra_assert (goal_alt_number >= 0);
3572 lra_set_used_insn_alternative (curr_insn, goal_alt_number);
3574 if (lra_dump_file != NULL)
3576 const char *p;
3578 fprintf (lra_dump_file, " Choosing alt %d in insn %u:",
3579 goal_alt_number, INSN_UID (curr_insn));
3580 for (i = 0; i < n_operands; i++)
3582 p = (curr_static_id->operand_alternative
3583 [goal_alt_number * n_operands + i].constraint);
3584 if (*p == '\0')
3585 continue;
3586 fprintf (lra_dump_file, " (%d) ", i);
3587 for (; *p != '\0' && *p != ',' && *p != '#'; p++)
3588 fputc (*p, lra_dump_file);
3590 if (INSN_CODE (curr_insn) >= 0
3591 && (p = get_insn_name (INSN_CODE (curr_insn))) != NULL)
3592 fprintf (lra_dump_file, " {%s}", p);
3593 if (curr_id->sp_offset != 0)
3594 fprintf (lra_dump_file, " (sp_off=%" HOST_WIDE_INT_PRINT "d)",
3595 curr_id->sp_offset);
3596 fprintf (lra_dump_file, "\n");
3599 /* Right now, for any pair of operands I and J that are required to
3600 match, with J < I, goal_alt_matches[I] is J. Add I to
3601 goal_alt_matched[J]. */
3603 for (i = 0; i < n_operands; i++)
3604 if ((j = goal_alt_matches[i]) >= 0)
3606 for (k = 0; goal_alt_matched[j][k] >= 0; k++)
3608 /* We allow matching one output operand and several input
3609 operands. */
3610 lra_assert (k == 0
3611 || (curr_static_id->operand[j].type == OP_OUT
3612 && curr_static_id->operand[i].type == OP_IN
3613 && (curr_static_id->operand
3614 [goal_alt_matched[j][0]].type == OP_IN)));
3615 goal_alt_matched[j][k] = i;
3616 goal_alt_matched[j][k + 1] = -1;
3619 for (i = 0; i < n_operands; i++)
3620 goal_alt_win[i] |= goal_alt_match_win[i];
3622 /* Any constants that aren't allowed and can't be reloaded into
3623 registers are here changed into memory references. */
3624 for (i = 0; i < n_operands; i++)
3625 if (goal_alt_win[i])
3627 int regno;
3628 enum reg_class new_class;
3629 rtx reg = *curr_id->operand_loc[i];
3631 if (GET_CODE (reg) == SUBREG)
3632 reg = SUBREG_REG (reg);
3634 if (REG_P (reg) && (regno = REGNO (reg)) >= FIRST_PSEUDO_REGISTER)
3636 bool ok_p = in_class_p (reg, goal_alt[i], &new_class);
3638 if (new_class != NO_REGS && get_reg_class (regno) != new_class)
3640 lra_assert (ok_p);
3641 lra_change_class (regno, new_class, " Change to", true);
3645 else
3647 const char *constraint;
3648 char c;
3649 rtx op = *curr_id->operand_loc[i];
3650 rtx subreg = NULL_RTX;
3651 machine_mode mode = curr_operand_mode[i];
3653 if (GET_CODE (op) == SUBREG)
3655 subreg = op;
3656 op = SUBREG_REG (op);
3657 mode = GET_MODE (op);
3660 if (CONST_POOL_OK_P (mode, op)
3661 && ((targetm.preferred_reload_class
3662 (op, (enum reg_class) goal_alt[i]) == NO_REGS)
3663 || no_input_reloads_p))
3665 rtx tem = force_const_mem (mode, op);
3667 change_p = true;
3668 if (subreg != NULL_RTX)
3669 tem = gen_rtx_SUBREG (mode, tem, SUBREG_BYTE (subreg));
3671 *curr_id->operand_loc[i] = tem;
3672 lra_update_dup (curr_id, i);
3673 process_address (i, false, &before, &after);
3675 /* If the alternative accepts constant pool refs directly
3676 there will be no reload needed at all. */
3677 if (subreg != NULL_RTX)
3678 continue;
3679 /* Skip alternatives before the one requested. */
3680 constraint = (curr_static_id->operand_alternative
3681 [goal_alt_number * n_operands + i].constraint);
3682 for (;
3683 (c = *constraint) && c != ',' && c != '#';
3684 constraint += CONSTRAINT_LEN (c, constraint))
3686 enum constraint_num cn = lookup_constraint (constraint);
3687 if (insn_extra_memory_constraint (cn)
3688 && satisfies_memory_constraint_p (tem, cn))
3689 break;
3691 if (c == '\0' || c == ',' || c == '#')
3692 continue;
3694 goal_alt_win[i] = true;
3698 for (i = 0; i < n_operands; i++)
3700 int regno;
3701 bool optional_p = false;
3702 rtx old, new_reg;
3703 rtx op = *curr_id->operand_loc[i];
3705 if (goal_alt_win[i])
3707 if (goal_alt[i] == NO_REGS
3708 && REG_P (op)
3709 /* When we assign NO_REGS it means that we will not
3710 assign a hard register to the scratch pseudo by
3711 assigment pass and the scratch pseudo will be
3712 spilled. Spilled scratch pseudos are transformed
3713 back to scratches at the LRA end. */
3714 && lra_former_scratch_operand_p (curr_insn, i))
3716 int regno = REGNO (op);
3717 lra_change_class (regno, NO_REGS, " Change to", true);
3718 if (lra_get_regno_hard_regno (regno) >= 0)
3719 /* We don't have to mark all insn affected by the
3720 spilled pseudo as there is only one such insn, the
3721 current one. */
3722 reg_renumber[regno] = -1;
3724 /* We can do an optional reload. If the pseudo got a hard
3725 reg, we might improve the code through inheritance. If
3726 it does not get a hard register we coalesce memory/memory
3727 moves later. Ignore move insns to avoid cycling. */
3728 if (! lra_simple_p
3729 && lra_undo_inheritance_iter < LRA_MAX_INHERITANCE_PASSES
3730 && goal_alt[i] != NO_REGS && REG_P (op)
3731 && (regno = REGNO (op)) >= FIRST_PSEUDO_REGISTER
3732 && regno < new_regno_start
3733 && ! lra_former_scratch_p (regno)
3734 && reg_renumber[regno] < 0
3735 && (curr_insn_set == NULL_RTX
3736 || !((REG_P (SET_SRC (curr_insn_set))
3737 || MEM_P (SET_SRC (curr_insn_set))
3738 || GET_CODE (SET_SRC (curr_insn_set)) == SUBREG)
3739 && (REG_P (SET_DEST (curr_insn_set))
3740 || MEM_P (SET_DEST (curr_insn_set))
3741 || GET_CODE (SET_DEST (curr_insn_set)) == SUBREG))))
3742 optional_p = true;
3743 else
3744 continue;
3747 /* Operands that match previous ones have already been handled. */
3748 if (goal_alt_matches[i] >= 0)
3749 continue;
3751 /* We should not have an operand with a non-offsettable address
3752 appearing where an offsettable address will do. It also may
3753 be a case when the address should be special in other words
3754 not a general one (e.g. it needs no index reg). */
3755 if (goal_alt_matched[i][0] == -1 && goal_alt_offmemok[i] && MEM_P (op))
3757 enum reg_class rclass;
3758 rtx *loc = &XEXP (op, 0);
3759 enum rtx_code code = GET_CODE (*loc);
3761 push_to_sequence (before);
3762 rclass = base_reg_class (GET_MODE (op), MEM_ADDR_SPACE (op),
3763 MEM, SCRATCH);
3764 if (GET_RTX_CLASS (code) == RTX_AUTOINC)
3765 new_reg = emit_inc (rclass, *loc, *loc,
3766 /* This value does not matter for MODIFY. */
3767 GET_MODE_SIZE (GET_MODE (op)));
3768 else if (get_reload_reg (OP_IN, Pmode, *loc, rclass, FALSE,
3769 "offsetable address", &new_reg))
3770 lra_emit_move (new_reg, *loc);
3771 before = get_insns ();
3772 end_sequence ();
3773 *loc = new_reg;
3774 lra_update_dup (curr_id, i);
3776 else if (goal_alt_matched[i][0] == -1)
3778 machine_mode mode;
3779 rtx reg, *loc;
3780 int hard_regno, byte;
3781 enum op_type type = curr_static_id->operand[i].type;
3783 loc = curr_id->operand_loc[i];
3784 mode = curr_operand_mode[i];
3785 if (GET_CODE (*loc) == SUBREG)
3787 reg = SUBREG_REG (*loc);
3788 byte = SUBREG_BYTE (*loc);
3789 if (REG_P (reg)
3790 /* Strict_low_part requires reload the register not
3791 the sub-register. */
3792 && (curr_static_id->operand[i].strict_low
3793 || (GET_MODE_SIZE (mode)
3794 <= GET_MODE_SIZE (GET_MODE (reg))
3795 && (hard_regno
3796 = get_try_hard_regno (REGNO (reg))) >= 0
3797 && (simplify_subreg_regno
3798 (hard_regno,
3799 GET_MODE (reg), byte, mode) < 0)
3800 && (goal_alt[i] == NO_REGS
3801 || (simplify_subreg_regno
3802 (ira_class_hard_regs[goal_alt[i]][0],
3803 GET_MODE (reg), byte, mode) >= 0)))))
3805 if (type == OP_OUT)
3806 type = OP_INOUT;
3807 loc = &SUBREG_REG (*loc);
3808 mode = GET_MODE (*loc);
3811 old = *loc;
3812 if (get_reload_reg (type, mode, old, goal_alt[i],
3813 loc != curr_id->operand_loc[i], "", &new_reg)
3814 && type != OP_OUT)
3816 push_to_sequence (before);
3817 lra_emit_move (new_reg, old);
3818 before = get_insns ();
3819 end_sequence ();
3821 *loc = new_reg;
3822 if (type != OP_IN
3823 && find_reg_note (curr_insn, REG_UNUSED, old) == NULL_RTX)
3825 start_sequence ();
3826 lra_emit_move (type == OP_INOUT ? copy_rtx (old) : old, new_reg);
3827 emit_insn (after);
3828 after = get_insns ();
3829 end_sequence ();
3830 *loc = new_reg;
3832 for (j = 0; j < goal_alt_dont_inherit_ops_num; j++)
3833 if (goal_alt_dont_inherit_ops[j] == i)
3835 lra_set_regno_unique_value (REGNO (new_reg));
3836 break;
3838 lra_update_dup (curr_id, i);
3840 else if (curr_static_id->operand[i].type == OP_IN
3841 && (curr_static_id->operand[goal_alt_matched[i][0]].type
3842 == OP_OUT))
3844 /* generate reloads for input and matched outputs. */
3845 match_inputs[0] = i;
3846 match_inputs[1] = -1;
3847 match_reload (goal_alt_matched[i][0], match_inputs,
3848 goal_alt[i], &before, &after);
3850 else if (curr_static_id->operand[i].type == OP_OUT
3851 && (curr_static_id->operand[goal_alt_matched[i][0]].type
3852 == OP_IN))
3853 /* Generate reloads for output and matched inputs. */
3854 match_reload (i, goal_alt_matched[i], goal_alt[i], &before, &after);
3855 else if (curr_static_id->operand[i].type == OP_IN
3856 && (curr_static_id->operand[goal_alt_matched[i][0]].type
3857 == OP_IN))
3859 /* Generate reloads for matched inputs. */
3860 match_inputs[0] = i;
3861 for (j = 0; (k = goal_alt_matched[i][j]) >= 0; j++)
3862 match_inputs[j + 1] = k;
3863 match_inputs[j + 1] = -1;
3864 match_reload (-1, match_inputs, goal_alt[i], &before, &after);
3866 else
3867 /* We must generate code in any case when function
3868 process_alt_operands decides that it is possible. */
3869 gcc_unreachable ();
3870 if (optional_p)
3872 lra_assert (REG_P (op));
3873 regno = REGNO (op);
3874 op = *curr_id->operand_loc[i]; /* Substitution. */
3875 if (GET_CODE (op) == SUBREG)
3876 op = SUBREG_REG (op);
3877 gcc_assert (REG_P (op) && (int) REGNO (op) >= new_regno_start);
3878 bitmap_set_bit (&lra_optional_reload_pseudos, REGNO (op));
3879 lra_reg_info[REGNO (op)].restore_regno = regno;
3880 if (lra_dump_file != NULL)
3881 fprintf (lra_dump_file,
3882 " Making reload reg %d for reg %d optional\n",
3883 REGNO (op), regno);
3886 if (before != NULL_RTX || after != NULL_RTX
3887 || max_regno_before != max_reg_num ())
3888 change_p = true;
3889 if (change_p)
3891 lra_update_operator_dups (curr_id);
3892 /* Something changes -- process the insn. */
3893 lra_update_insn_regno_info (curr_insn);
3895 lra_process_new_insns (curr_insn, before, after, "Inserting insn reload");
3896 return change_p;
3899 /* Return true if INSN satisfies all constraints. In other words, no
3900 reload insns are needed. */
3901 bool
3902 lra_constrain_insn (rtx_insn *insn)
3904 int saved_new_regno_start = new_regno_start;
3905 int saved_new_insn_uid_start = new_insn_uid_start;
3906 bool change_p;
3908 curr_insn = insn;
3909 curr_id = lra_get_insn_recog_data (curr_insn);
3910 curr_static_id = curr_id->insn_static_data;
3911 new_insn_uid_start = get_max_uid ();
3912 new_regno_start = max_reg_num ();
3913 change_p = curr_insn_transform (true);
3914 new_regno_start = saved_new_regno_start;
3915 new_insn_uid_start = saved_new_insn_uid_start;
3916 return ! change_p;
3919 /* Return true if X is in LIST. */
3920 static bool
3921 in_list_p (rtx x, rtx list)
3923 for (; list != NULL_RTX; list = XEXP (list, 1))
3924 if (XEXP (list, 0) == x)
3925 return true;
3926 return false;
3929 /* Return true if X contains an allocatable hard register (if
3930 HARD_REG_P) or a (spilled if SPILLED_P) pseudo. */
3931 static bool
3932 contains_reg_p (rtx x, bool hard_reg_p, bool spilled_p)
3934 int i, j;
3935 const char *fmt;
3936 enum rtx_code code;
3938 code = GET_CODE (x);
3939 if (REG_P (x))
3941 int regno = REGNO (x);
3942 HARD_REG_SET alloc_regs;
3944 if (hard_reg_p)
3946 if (regno >= FIRST_PSEUDO_REGISTER)
3947 regno = lra_get_regno_hard_regno (regno);
3948 if (regno < 0)
3949 return false;
3950 COMPL_HARD_REG_SET (alloc_regs, lra_no_alloc_regs);
3951 return overlaps_hard_reg_set_p (alloc_regs, GET_MODE (x), regno);
3953 else
3955 if (regno < FIRST_PSEUDO_REGISTER)
3956 return false;
3957 if (! spilled_p)
3958 return true;
3959 return lra_get_regno_hard_regno (regno) < 0;
3962 fmt = GET_RTX_FORMAT (code);
3963 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
3965 if (fmt[i] == 'e')
3967 if (contains_reg_p (XEXP (x, i), hard_reg_p, spilled_p))
3968 return true;
3970 else if (fmt[i] == 'E')
3972 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
3973 if (contains_reg_p (XVECEXP (x, i, j), hard_reg_p, spilled_p))
3974 return true;
3977 return false;
3980 /* Return true if X contains a symbol reg. */
3981 static bool
3982 contains_symbol_ref_p (rtx x)
3984 int i, j;
3985 const char *fmt;
3986 enum rtx_code code;
3988 code = GET_CODE (x);
3989 if (code == SYMBOL_REF)
3990 return true;
3991 fmt = GET_RTX_FORMAT (code);
3992 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
3994 if (fmt[i] == 'e')
3996 if (contains_symbol_ref_p (XEXP (x, i)))
3997 return true;
3999 else if (fmt[i] == 'E')
4001 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
4002 if (contains_symbol_ref_p (XVECEXP (x, i, j)))
4003 return true;
4006 return false;
4009 /* Process all regs in location *LOC and change them on equivalent
4010 substitution. Return true if any change was done. */
4011 static bool
4012 loc_equivalence_change_p (rtx *loc)
4014 rtx subst, reg, x = *loc;
4015 bool result = false;
4016 enum rtx_code code = GET_CODE (x);
4017 const char *fmt;
4018 int i, j;
4020 if (code == SUBREG)
4022 reg = SUBREG_REG (x);
4023 if ((subst = get_equiv_with_elimination (reg, curr_insn)) != reg
4024 && GET_MODE (subst) == VOIDmode)
4026 /* We cannot reload debug location. Simplify subreg here
4027 while we know the inner mode. */
4028 *loc = simplify_gen_subreg (GET_MODE (x), subst,
4029 GET_MODE (reg), SUBREG_BYTE (x));
4030 return true;
4033 if (code == REG && (subst = get_equiv_with_elimination (x, curr_insn)) != x)
4035 *loc = subst;
4036 return true;
4039 /* Scan all the operand sub-expressions. */
4040 fmt = GET_RTX_FORMAT (code);
4041 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
4043 if (fmt[i] == 'e')
4044 result = loc_equivalence_change_p (&XEXP (x, i)) || result;
4045 else if (fmt[i] == 'E')
4046 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
4047 result
4048 = loc_equivalence_change_p (&XVECEXP (x, i, j)) || result;
4050 return result;
4053 /* Similar to loc_equivalence_change_p, but for use as
4054 simplify_replace_fn_rtx callback. DATA is insn for which the
4055 elimination is done. If it null we don't do the elimination. */
4056 static rtx
4057 loc_equivalence_callback (rtx loc, const_rtx, void *data)
4059 if (!REG_P (loc))
4060 return NULL_RTX;
4062 rtx subst = (data == NULL
4063 ? get_equiv (loc) : get_equiv_with_elimination (loc, (rtx_insn *) data));
4064 if (subst != loc)
4065 return subst;
4067 return NULL_RTX;
4070 /* Maximum number of generated reload insns per an insn. It is for
4071 preventing this pass cycling in a bug case. */
4072 #define MAX_RELOAD_INSNS_NUMBER LRA_MAX_INSN_RELOADS
4074 /* The current iteration number of this LRA pass. */
4075 int lra_constraint_iter;
4077 /* True if we substituted equiv which needs checking register
4078 allocation correctness because the equivalent value contains
4079 allocatable hard registers or when we restore multi-register
4080 pseudo. */
4081 bool lra_risky_transformations_p;
4083 /* Return true if REGNO is referenced in more than one block. */
4084 static bool
4085 multi_block_pseudo_p (int regno)
4087 basic_block bb = NULL;
4088 unsigned int uid;
4089 bitmap_iterator bi;
4091 if (regno < FIRST_PSEUDO_REGISTER)
4092 return false;
4094 EXECUTE_IF_SET_IN_BITMAP (&lra_reg_info[regno].insn_bitmap, 0, uid, bi)
4095 if (bb == NULL)
4096 bb = BLOCK_FOR_INSN (lra_insn_recog_data[uid]->insn);
4097 else if (BLOCK_FOR_INSN (lra_insn_recog_data[uid]->insn) != bb)
4098 return true;
4099 return false;
4102 /* Return true if LIST contains a deleted insn. */
4103 static bool
4104 contains_deleted_insn_p (rtx_insn_list *list)
4106 for (; list != NULL_RTX; list = list->next ())
4107 if (NOTE_P (list->insn ())
4108 && NOTE_KIND (list->insn ()) == NOTE_INSN_DELETED)
4109 return true;
4110 return false;
4113 /* Return true if X contains a pseudo dying in INSN. */
4114 static bool
4115 dead_pseudo_p (rtx x, rtx insn)
4117 int i, j;
4118 const char *fmt;
4119 enum rtx_code code;
4121 if (REG_P (x))
4122 return (insn != NULL_RTX
4123 && find_regno_note (insn, REG_DEAD, REGNO (x)) != NULL_RTX);
4124 code = GET_CODE (x);
4125 fmt = GET_RTX_FORMAT (code);
4126 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
4128 if (fmt[i] == 'e')
4130 if (dead_pseudo_p (XEXP (x, i), insn))
4131 return true;
4133 else if (fmt[i] == 'E')
4135 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
4136 if (dead_pseudo_p (XVECEXP (x, i, j), insn))
4137 return true;
4140 return false;
4143 /* Return true if INSN contains a dying pseudo in INSN right hand
4144 side. */
4145 static bool
4146 insn_rhs_dead_pseudo_p (rtx_insn *insn)
4148 rtx set = single_set (insn);
4150 gcc_assert (set != NULL);
4151 return dead_pseudo_p (SET_SRC (set), insn);
4154 /* Return true if any init insn of REGNO contains a dying pseudo in
4155 insn right hand side. */
4156 static bool
4157 init_insn_rhs_dead_pseudo_p (int regno)
4159 rtx_insn_list *insns = ira_reg_equiv[regno].init_insns;
4161 if (insns == NULL)
4162 return false;
4163 for (; insns != NULL_RTX; insns = insns->next ())
4164 if (insn_rhs_dead_pseudo_p (insns->insn ()))
4165 return true;
4166 return false;
4169 /* Return TRUE if REGNO has a reverse equivalence. The equivalence is
4170 reverse only if we have one init insn with given REGNO as a
4171 source. */
4172 static bool
4173 reverse_equiv_p (int regno)
4175 rtx_insn_list *insns = ira_reg_equiv[regno].init_insns;
4176 rtx set;
4178 if (insns == NULL)
4179 return false;
4180 if (! INSN_P (insns->insn ())
4181 || insns->next () != NULL)
4182 return false;
4183 if ((set = single_set (insns->insn ())) == NULL_RTX)
4184 return false;
4185 return REG_P (SET_SRC (set)) && (int) REGNO (SET_SRC (set)) == regno;
4188 /* Return TRUE if REGNO was reloaded in an equivalence init insn. We
4189 call this function only for non-reverse equivalence. */
4190 static bool
4191 contains_reloaded_insn_p (int regno)
4193 rtx set;
4194 rtx_insn_list *list = ira_reg_equiv[regno].init_insns;
4196 for (; list != NULL; list = list->next ())
4197 if ((set = single_set (list->insn ())) == NULL_RTX
4198 || ! REG_P (SET_DEST (set))
4199 || (int) REGNO (SET_DEST (set)) != regno)
4200 return true;
4201 return false;
4204 /* Entry function of LRA constraint pass. Return true if the
4205 constraint pass did change the code. */
4206 bool
4207 lra_constraints (bool first_p)
4209 bool changed_p;
4210 int i, hard_regno, new_insns_num;
4211 unsigned int min_len, new_min_len, uid;
4212 rtx set, x, reg, dest_reg;
4213 basic_block last_bb;
4214 bitmap_head equiv_insn_bitmap;
4215 bitmap_iterator bi;
4217 lra_constraint_iter++;
4218 if (lra_dump_file != NULL)
4219 fprintf (lra_dump_file, "\n********** Local #%d: **********\n\n",
4220 lra_constraint_iter);
4221 changed_p = false;
4222 if (pic_offset_table_rtx
4223 && REGNO (pic_offset_table_rtx) >= FIRST_PSEUDO_REGISTER)
4224 lra_risky_transformations_p = true;
4225 else
4226 lra_risky_transformations_p = false;
4227 new_insn_uid_start = get_max_uid ();
4228 new_regno_start = first_p ? lra_constraint_new_regno_start : max_reg_num ();
4229 /* Mark used hard regs for target stack size calulations. */
4230 for (i = FIRST_PSEUDO_REGISTER; i < new_regno_start; i++)
4231 if (lra_reg_info[i].nrefs != 0
4232 && (hard_regno = lra_get_regno_hard_regno (i)) >= 0)
4234 int j, nregs;
4236 nregs = hard_regno_nregs[hard_regno][lra_reg_info[i].biggest_mode];
4237 for (j = 0; j < nregs; j++)
4238 df_set_regs_ever_live (hard_regno + j, true);
4240 /* Do elimination before the equivalence processing as we can spill
4241 some pseudos during elimination. */
4242 lra_eliminate (false, first_p);
4243 bitmap_initialize (&equiv_insn_bitmap, &reg_obstack);
4244 for (i = FIRST_PSEUDO_REGISTER; i < new_regno_start; i++)
4245 if (lra_reg_info[i].nrefs != 0)
4247 ira_reg_equiv[i].profitable_p = true;
4248 reg = regno_reg_rtx[i];
4249 if (lra_get_regno_hard_regno (i) < 0 && (x = get_equiv (reg)) != reg)
4251 bool pseudo_p = contains_reg_p (x, false, false);
4253 /* After RTL transformation, we can not guarantee that
4254 pseudo in the substitution was not reloaded which might
4255 make equivalence invalid. For example, in reverse
4256 equiv of p0
4258 p0 <- ...
4260 equiv_mem <- p0
4262 the memory address register was reloaded before the 2nd
4263 insn. */
4264 if ((! first_p && pseudo_p)
4265 /* We don't use DF for compilation speed sake. So it
4266 is problematic to update live info when we use an
4267 equivalence containing pseudos in more than one
4268 BB. */
4269 || (pseudo_p && multi_block_pseudo_p (i))
4270 /* If an init insn was deleted for some reason, cancel
4271 the equiv. We could update the equiv insns after
4272 transformations including an equiv insn deletion
4273 but it is not worthy as such cases are extremely
4274 rare. */
4275 || contains_deleted_insn_p (ira_reg_equiv[i].init_insns)
4276 /* If it is not a reverse equivalence, we check that a
4277 pseudo in rhs of the init insn is not dying in the
4278 insn. Otherwise, the live info at the beginning of
4279 the corresponding BB might be wrong after we
4280 removed the insn. When the equiv can be a
4281 constant, the right hand side of the init insn can
4282 be a pseudo. */
4283 || (! reverse_equiv_p (i)
4284 && (init_insn_rhs_dead_pseudo_p (i)
4285 /* If we reloaded the pseudo in an equivalence
4286 init insn, we can not remove the equiv init
4287 insns and the init insns might write into
4288 const memory in this case. */
4289 || contains_reloaded_insn_p (i)))
4290 /* Prevent access beyond equivalent memory for
4291 paradoxical subregs. */
4292 || (MEM_P (x)
4293 && (GET_MODE_SIZE (lra_reg_info[i].biggest_mode)
4294 > GET_MODE_SIZE (GET_MODE (x))))
4295 || (pic_offset_table_rtx
4296 && ((CONST_POOL_OK_P (PSEUDO_REGNO_MODE (i), x)
4297 && (targetm.preferred_reload_class
4298 (x, lra_get_allocno_class (i)) == NO_REGS))
4299 || contains_symbol_ref_p (x))))
4300 ira_reg_equiv[i].defined_p = false;
4301 if (contains_reg_p (x, false, true))
4302 ira_reg_equiv[i].profitable_p = false;
4303 if (get_equiv (reg) != reg)
4304 bitmap_ior_into (&equiv_insn_bitmap, &lra_reg_info[i].insn_bitmap);
4307 for (i = FIRST_PSEUDO_REGISTER; i < new_regno_start; i++)
4308 update_equiv (i);
4309 /* We should add all insns containing pseudos which should be
4310 substituted by their equivalences. */
4311 EXECUTE_IF_SET_IN_BITMAP (&equiv_insn_bitmap, 0, uid, bi)
4312 lra_push_insn_by_uid (uid);
4313 min_len = lra_insn_stack_length ();
4314 new_insns_num = 0;
4315 last_bb = NULL;
4316 changed_p = false;
4317 while ((new_min_len = lra_insn_stack_length ()) != 0)
4319 curr_insn = lra_pop_insn ();
4320 --new_min_len;
4321 curr_bb = BLOCK_FOR_INSN (curr_insn);
4322 if (curr_bb != last_bb)
4324 last_bb = curr_bb;
4325 bb_reload_num = lra_curr_reload_num;
4327 if (min_len > new_min_len)
4329 min_len = new_min_len;
4330 new_insns_num = 0;
4332 if (new_insns_num > MAX_RELOAD_INSNS_NUMBER)
4333 internal_error
4334 ("Max. number of generated reload insns per insn is achieved (%d)\n",
4335 MAX_RELOAD_INSNS_NUMBER);
4336 new_insns_num++;
4337 if (DEBUG_INSN_P (curr_insn))
4339 /* We need to check equivalence in debug insn and change
4340 pseudo to the equivalent value if necessary. */
4341 curr_id = lra_get_insn_recog_data (curr_insn);
4342 if (bitmap_bit_p (&equiv_insn_bitmap, INSN_UID (curr_insn)))
4344 rtx old = *curr_id->operand_loc[0];
4345 *curr_id->operand_loc[0]
4346 = simplify_replace_fn_rtx (old, NULL_RTX,
4347 loc_equivalence_callback, curr_insn);
4348 if (old != *curr_id->operand_loc[0])
4350 lra_update_insn_regno_info (curr_insn);
4351 changed_p = true;
4355 else if (INSN_P (curr_insn))
4357 if ((set = single_set (curr_insn)) != NULL_RTX)
4359 dest_reg = SET_DEST (set);
4360 /* The equivalence pseudo could be set up as SUBREG in a
4361 case when it is a call restore insn in a mode
4362 different from the pseudo mode. */
4363 if (GET_CODE (dest_reg) == SUBREG)
4364 dest_reg = SUBREG_REG (dest_reg);
4365 if ((REG_P (dest_reg)
4366 && (x = get_equiv (dest_reg)) != dest_reg
4367 /* Remove insns which set up a pseudo whose value
4368 can not be changed. Such insns might be not in
4369 init_insns because we don't update equiv data
4370 during insn transformations.
4372 As an example, let suppose that a pseudo got
4373 hard register and on the 1st pass was not
4374 changed to equivalent constant. We generate an
4375 additional insn setting up the pseudo because of
4376 secondary memory movement. Then the pseudo is
4377 spilled and we use the equiv constant. In this
4378 case we should remove the additional insn and
4379 this insn is not init_insns list. */
4380 && (! MEM_P (x) || MEM_READONLY_P (x)
4381 /* Check that this is actually an insn setting
4382 up the equivalence. */
4383 || in_list_p (curr_insn,
4384 ira_reg_equiv
4385 [REGNO (dest_reg)].init_insns)))
4386 || (((x = get_equiv (SET_SRC (set))) != SET_SRC (set))
4387 && in_list_p (curr_insn,
4388 ira_reg_equiv
4389 [REGNO (SET_SRC (set))].init_insns)))
4391 /* This is equiv init insn of pseudo which did not get a
4392 hard register -- remove the insn. */
4393 if (lra_dump_file != NULL)
4395 fprintf (lra_dump_file,
4396 " Removing equiv init insn %i (freq=%d)\n",
4397 INSN_UID (curr_insn),
4398 REG_FREQ_FROM_BB (BLOCK_FOR_INSN (curr_insn)));
4399 dump_insn_slim (lra_dump_file, curr_insn);
4401 if (contains_reg_p (x, true, false))
4402 lra_risky_transformations_p = true;
4403 lra_set_insn_deleted (curr_insn);
4404 continue;
4407 curr_id = lra_get_insn_recog_data (curr_insn);
4408 curr_static_id = curr_id->insn_static_data;
4409 init_curr_insn_input_reloads ();
4410 init_curr_operand_mode ();
4411 if (curr_insn_transform (false))
4412 changed_p = true;
4413 /* Check non-transformed insns too for equiv change as USE
4414 or CLOBBER don't need reloads but can contain pseudos
4415 being changed on their equivalences. */
4416 else if (bitmap_bit_p (&equiv_insn_bitmap, INSN_UID (curr_insn))
4417 && loc_equivalence_change_p (&PATTERN (curr_insn)))
4419 lra_update_insn_regno_info (curr_insn);
4420 changed_p = true;
4424 bitmap_clear (&equiv_insn_bitmap);
4425 /* If we used a new hard regno, changed_p should be true because the
4426 hard reg is assigned to a new pseudo. */
4427 #ifdef ENABLE_CHECKING
4428 if (! changed_p)
4430 for (i = FIRST_PSEUDO_REGISTER; i < new_regno_start; i++)
4431 if (lra_reg_info[i].nrefs != 0
4432 && (hard_regno = lra_get_regno_hard_regno (i)) >= 0)
4434 int j, nregs = hard_regno_nregs[hard_regno][PSEUDO_REGNO_MODE (i)];
4436 for (j = 0; j < nregs; j++)
4437 lra_assert (df_regs_ever_live_p (hard_regno + j));
4440 #endif
4441 return changed_p;
4444 /* Initiate the LRA constraint pass. It is done once per
4445 function. */
4446 void
4447 lra_constraints_init (void)
4451 /* Finalize the LRA constraint pass. It is done once per
4452 function. */
4453 void
4454 lra_constraints_finish (void)
4460 /* This page contains code to do inheritance/split
4461 transformations. */
4463 /* Number of reloads passed so far in current EBB. */
4464 static int reloads_num;
4466 /* Number of calls passed so far in current EBB. */
4467 static int calls_num;
4469 /* Current reload pseudo check for validity of elements in
4470 USAGE_INSNS. */
4471 static int curr_usage_insns_check;
4473 /* Info about last usage of registers in EBB to do inheritance/split
4474 transformation. Inheritance transformation is done from a spilled
4475 pseudo and split transformations from a hard register or a pseudo
4476 assigned to a hard register. */
4477 struct usage_insns
4479 /* If the value is equal to CURR_USAGE_INSNS_CHECK, then the member
4480 value INSNS is valid. The insns is chain of optional debug insns
4481 and a finishing non-debug insn using the corresponding reg. The
4482 value is also used to mark the registers which are set up in the
4483 current insn. The negated insn uid is used for this. */
4484 int check;
4485 /* Value of global reloads_num at the last insn in INSNS. */
4486 int reloads_num;
4487 /* Value of global reloads_nums at the last insn in INSNS. */
4488 int calls_num;
4489 /* It can be true only for splitting. And it means that the restore
4490 insn should be put after insn given by the following member. */
4491 bool after_p;
4492 /* Next insns in the current EBB which use the original reg and the
4493 original reg value is not changed between the current insn and
4494 the next insns. In order words, e.g. for inheritance, if we need
4495 to use the original reg value again in the next insns we can try
4496 to use the value in a hard register from a reload insn of the
4497 current insn. */
4498 rtx insns;
4501 /* Map: regno -> corresponding pseudo usage insns. */
4502 static struct usage_insns *usage_insns;
4504 static void
4505 setup_next_usage_insn (int regno, rtx insn, int reloads_num, bool after_p)
4507 usage_insns[regno].check = curr_usage_insns_check;
4508 usage_insns[regno].insns = insn;
4509 usage_insns[regno].reloads_num = reloads_num;
4510 usage_insns[regno].calls_num = calls_num;
4511 usage_insns[regno].after_p = after_p;
4514 /* The function is used to form list REGNO usages which consists of
4515 optional debug insns finished by a non-debug insn using REGNO.
4516 RELOADS_NUM is current number of reload insns processed so far. */
4517 static void
4518 add_next_usage_insn (int regno, rtx insn, int reloads_num)
4520 rtx next_usage_insns;
4522 if (usage_insns[regno].check == curr_usage_insns_check
4523 && (next_usage_insns = usage_insns[regno].insns) != NULL_RTX
4524 && DEBUG_INSN_P (insn))
4526 /* Check that we did not add the debug insn yet. */
4527 if (next_usage_insns != insn
4528 && (GET_CODE (next_usage_insns) != INSN_LIST
4529 || XEXP (next_usage_insns, 0) != insn))
4530 usage_insns[regno].insns = gen_rtx_INSN_LIST (VOIDmode, insn,
4531 next_usage_insns);
4533 else if (NONDEBUG_INSN_P (insn))
4534 setup_next_usage_insn (regno, insn, reloads_num, false);
4535 else
4536 usage_insns[regno].check = 0;
4539 /* Return first non-debug insn in list USAGE_INSNS. */
4540 static rtx_insn *
4541 skip_usage_debug_insns (rtx usage_insns)
4543 rtx insn;
4545 /* Skip debug insns. */
4546 for (insn = usage_insns;
4547 insn != NULL_RTX && GET_CODE (insn) == INSN_LIST;
4548 insn = XEXP (insn, 1))
4550 return safe_as_a <rtx_insn *> (insn);
4553 /* Return true if we need secondary memory moves for insn in
4554 USAGE_INSNS after inserting inherited pseudo of class INHER_CL
4555 into the insn. */
4556 static bool
4557 check_secondary_memory_needed_p (enum reg_class inher_cl ATTRIBUTE_UNUSED,
4558 rtx usage_insns ATTRIBUTE_UNUSED)
4560 #ifndef SECONDARY_MEMORY_NEEDED
4561 return false;
4562 #else
4563 rtx_insn *insn;
4564 rtx set, dest;
4565 enum reg_class cl;
4567 if (inher_cl == ALL_REGS
4568 || (insn = skip_usage_debug_insns (usage_insns)) == NULL_RTX)
4569 return false;
4570 lra_assert (INSN_P (insn));
4571 if ((set = single_set (insn)) == NULL_RTX || ! REG_P (SET_DEST (set)))
4572 return false;
4573 dest = SET_DEST (set);
4574 if (! REG_P (dest))
4575 return false;
4576 lra_assert (inher_cl != NO_REGS);
4577 cl = get_reg_class (REGNO (dest));
4578 return (cl != NO_REGS && cl != ALL_REGS
4579 && SECONDARY_MEMORY_NEEDED (inher_cl, cl, GET_MODE (dest)));
4580 #endif
4583 /* Registers involved in inheritance/split in the current EBB
4584 (inheritance/split pseudos and original registers). */
4585 static bitmap_head check_only_regs;
4587 /* Do inheritance transformations for insn INSN, which defines (if
4588 DEF_P) or uses ORIGINAL_REGNO. NEXT_USAGE_INSNS specifies which
4589 instruction in the EBB next uses ORIGINAL_REGNO; it has the same
4590 form as the "insns" field of usage_insns. Return true if we
4591 succeed in such transformation.
4593 The transformations look like:
4595 p <- ... i <- ...
4596 ... p <- i (new insn)
4597 ... =>
4598 <- ... p ... <- ... i ...
4600 ... i <- p (new insn)
4601 <- ... p ... <- ... i ...
4602 ... =>
4603 <- ... p ... <- ... i ...
4604 where p is a spilled original pseudo and i is a new inheritance pseudo.
4607 The inheritance pseudo has the smallest class of two classes CL and
4608 class of ORIGINAL REGNO. */
4609 static bool
4610 inherit_reload_reg (bool def_p, int original_regno,
4611 enum reg_class cl, rtx_insn *insn, rtx next_usage_insns)
4613 if (optimize_function_for_size_p (cfun))
4614 return false;
4616 enum reg_class rclass = lra_get_allocno_class (original_regno);
4617 rtx original_reg = regno_reg_rtx[original_regno];
4618 rtx new_reg, usage_insn;
4619 rtx_insn *new_insns;
4621 lra_assert (! usage_insns[original_regno].after_p);
4622 if (lra_dump_file != NULL)
4623 fprintf (lra_dump_file,
4624 " <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
4625 if (! ira_reg_classes_intersect_p[cl][rclass])
4627 if (lra_dump_file != NULL)
4629 fprintf (lra_dump_file,
4630 " Rejecting inheritance for %d "
4631 "because of disjoint classes %s and %s\n",
4632 original_regno, reg_class_names[cl],
4633 reg_class_names[rclass]);
4634 fprintf (lra_dump_file,
4635 " >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
4637 return false;
4639 if ((ira_class_subset_p[cl][rclass] && cl != rclass)
4640 /* We don't use a subset of two classes because it can be
4641 NO_REGS. This transformation is still profitable in most
4642 cases even if the classes are not intersected as register
4643 move is probably cheaper than a memory load. */
4644 || ira_class_hard_regs_num[cl] < ira_class_hard_regs_num[rclass])
4646 if (lra_dump_file != NULL)
4647 fprintf (lra_dump_file, " Use smallest class of %s and %s\n",
4648 reg_class_names[cl], reg_class_names[rclass]);
4650 rclass = cl;
4652 if (check_secondary_memory_needed_p (rclass, next_usage_insns))
4654 /* Reject inheritance resulting in secondary memory moves.
4655 Otherwise, there is a danger in LRA cycling. Also such
4656 transformation will be unprofitable. */
4657 if (lra_dump_file != NULL)
4659 rtx_insn *insn = skip_usage_debug_insns (next_usage_insns);
4660 rtx set = single_set (insn);
4662 lra_assert (set != NULL_RTX);
4664 rtx dest = SET_DEST (set);
4666 lra_assert (REG_P (dest));
4667 fprintf (lra_dump_file,
4668 " Rejecting inheritance for insn %d(%s)<-%d(%s) "
4669 "as secondary mem is needed\n",
4670 REGNO (dest), reg_class_names[get_reg_class (REGNO (dest))],
4671 original_regno, reg_class_names[rclass]);
4672 fprintf (lra_dump_file,
4673 " >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
4675 return false;
4677 new_reg = lra_create_new_reg (GET_MODE (original_reg), original_reg,
4678 rclass, "inheritance");
4679 start_sequence ();
4680 if (def_p)
4681 lra_emit_move (original_reg, new_reg);
4682 else
4683 lra_emit_move (new_reg, original_reg);
4684 new_insns = get_insns ();
4685 end_sequence ();
4686 if (NEXT_INSN (new_insns) != NULL_RTX)
4688 if (lra_dump_file != NULL)
4690 fprintf (lra_dump_file,
4691 " Rejecting inheritance %d->%d "
4692 "as it results in 2 or more insns:\n",
4693 original_regno, REGNO (new_reg));
4694 dump_rtl_slim (lra_dump_file, new_insns, NULL, -1, 0);
4695 fprintf (lra_dump_file,
4696 " >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
4698 return false;
4700 lra_substitute_pseudo_within_insn (insn, original_regno, new_reg);
4701 lra_update_insn_regno_info (insn);
4702 if (! def_p)
4703 /* We now have a new usage insn for original regno. */
4704 setup_next_usage_insn (original_regno, new_insns, reloads_num, false);
4705 if (lra_dump_file != NULL)
4706 fprintf (lra_dump_file, " Original reg change %d->%d (bb%d):\n",
4707 original_regno, REGNO (new_reg), BLOCK_FOR_INSN (insn)->index);
4708 lra_reg_info[REGNO (new_reg)].restore_regno = original_regno;
4709 bitmap_set_bit (&check_only_regs, REGNO (new_reg));
4710 bitmap_set_bit (&check_only_regs, original_regno);
4711 bitmap_set_bit (&lra_inheritance_pseudos, REGNO (new_reg));
4712 if (def_p)
4713 lra_process_new_insns (insn, NULL, new_insns,
4714 "Add original<-inheritance");
4715 else
4716 lra_process_new_insns (insn, new_insns, NULL,
4717 "Add inheritance<-original");
4718 while (next_usage_insns != NULL_RTX)
4720 if (GET_CODE (next_usage_insns) != INSN_LIST)
4722 usage_insn = next_usage_insns;
4723 lra_assert (NONDEBUG_INSN_P (usage_insn));
4724 next_usage_insns = NULL;
4726 else
4728 usage_insn = XEXP (next_usage_insns, 0);
4729 lra_assert (DEBUG_INSN_P (usage_insn));
4730 next_usage_insns = XEXP (next_usage_insns, 1);
4732 lra_substitute_pseudo (&usage_insn, original_regno, new_reg);
4733 lra_update_insn_regno_info (as_a <rtx_insn *> (usage_insn));
4734 if (lra_dump_file != NULL)
4736 fprintf (lra_dump_file,
4737 " Inheritance reuse change %d->%d (bb%d):\n",
4738 original_regno, REGNO (new_reg),
4739 BLOCK_FOR_INSN (usage_insn)->index);
4740 dump_insn_slim (lra_dump_file, usage_insn);
4743 if (lra_dump_file != NULL)
4744 fprintf (lra_dump_file,
4745 " >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>\n");
4746 return true;
4749 /* Return true if we need a caller save/restore for pseudo REGNO which
4750 was assigned to a hard register. */
4751 static inline bool
4752 need_for_call_save_p (int regno)
4754 lra_assert (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] >= 0);
4755 return (usage_insns[regno].calls_num < calls_num
4756 && (overlaps_hard_reg_set_p
4757 ((flag_ipa_ra &&
4758 ! hard_reg_set_empty_p (lra_reg_info[regno].actual_call_used_reg_set))
4759 ? lra_reg_info[regno].actual_call_used_reg_set
4760 : call_used_reg_set,
4761 PSEUDO_REGNO_MODE (regno), reg_renumber[regno])
4762 || HARD_REGNO_CALL_PART_CLOBBERED (reg_renumber[regno],
4763 PSEUDO_REGNO_MODE (regno))));
4766 /* Global registers occurring in the current EBB. */
4767 static bitmap_head ebb_global_regs;
4769 /* Return true if we need a split for hard register REGNO or pseudo
4770 REGNO which was assigned to a hard register.
4771 POTENTIAL_RELOAD_HARD_REGS contains hard registers which might be
4772 used for reloads since the EBB end. It is an approximation of the
4773 used hard registers in the split range. The exact value would
4774 require expensive calculations. If we were aggressive with
4775 splitting because of the approximation, the split pseudo will save
4776 the same hard register assignment and will be removed in the undo
4777 pass. We still need the approximation because too aggressive
4778 splitting would result in too inaccurate cost calculation in the
4779 assignment pass because of too many generated moves which will be
4780 probably removed in the undo pass. */
4781 static inline bool
4782 need_for_split_p (HARD_REG_SET potential_reload_hard_regs, int regno)
4784 int hard_regno = regno < FIRST_PSEUDO_REGISTER ? regno : reg_renumber[regno];
4786 lra_assert (hard_regno >= 0);
4787 return ((TEST_HARD_REG_BIT (potential_reload_hard_regs, hard_regno)
4788 /* Don't split eliminable hard registers, otherwise we can
4789 split hard registers like hard frame pointer, which
4790 lives on BB start/end according to DF-infrastructure,
4791 when there is a pseudo assigned to the register and
4792 living in the same BB. */
4793 && (regno >= FIRST_PSEUDO_REGISTER
4794 || ! TEST_HARD_REG_BIT (eliminable_regset, hard_regno))
4795 && ! TEST_HARD_REG_BIT (lra_no_alloc_regs, hard_regno)
4796 /* Don't split call clobbered hard regs living through
4797 calls, otherwise we might have a check problem in the
4798 assign sub-pass as in the most cases (exception is a
4799 situation when lra_risky_transformations_p value is
4800 true) the assign pass assumes that all pseudos living
4801 through calls are assigned to call saved hard regs. */
4802 && (regno >= FIRST_PSEUDO_REGISTER
4803 || ! TEST_HARD_REG_BIT (call_used_reg_set, regno)
4804 || usage_insns[regno].calls_num == calls_num)
4805 /* We need at least 2 reloads to make pseudo splitting
4806 profitable. We should provide hard regno splitting in
4807 any case to solve 1st insn scheduling problem when
4808 moving hard register definition up might result in
4809 impossibility to find hard register for reload pseudo of
4810 small register class. */
4811 && (usage_insns[regno].reloads_num
4812 + (regno < FIRST_PSEUDO_REGISTER ? 0 : 3) < reloads_num)
4813 && (regno < FIRST_PSEUDO_REGISTER
4814 /* For short living pseudos, spilling + inheritance can
4815 be considered a substitution for splitting.
4816 Therefore we do not splitting for local pseudos. It
4817 decreases also aggressiveness of splitting. The
4818 minimal number of references is chosen taking into
4819 account that for 2 references splitting has no sense
4820 as we can just spill the pseudo. */
4821 || (regno >= FIRST_PSEUDO_REGISTER
4822 && lra_reg_info[regno].nrefs > 3
4823 && bitmap_bit_p (&ebb_global_regs, regno))))
4824 || (regno >= FIRST_PSEUDO_REGISTER && need_for_call_save_p (regno)));
4827 /* Return class for the split pseudo created from original pseudo with
4828 ALLOCNO_CLASS and MODE which got a hard register HARD_REGNO. We
4829 choose subclass of ALLOCNO_CLASS which contains HARD_REGNO and
4830 results in no secondary memory movements. */
4831 static enum reg_class
4832 choose_split_class (enum reg_class allocno_class,
4833 int hard_regno ATTRIBUTE_UNUSED,
4834 machine_mode mode ATTRIBUTE_UNUSED)
4836 #ifndef SECONDARY_MEMORY_NEEDED
4837 return allocno_class;
4838 #else
4839 int i;
4840 enum reg_class cl, best_cl = NO_REGS;
4841 enum reg_class hard_reg_class ATTRIBUTE_UNUSED
4842 = REGNO_REG_CLASS (hard_regno);
4844 if (! SECONDARY_MEMORY_NEEDED (allocno_class, allocno_class, mode)
4845 && TEST_HARD_REG_BIT (reg_class_contents[allocno_class], hard_regno))
4846 return allocno_class;
4847 for (i = 0;
4848 (cl = reg_class_subclasses[allocno_class][i]) != LIM_REG_CLASSES;
4849 i++)
4850 if (! SECONDARY_MEMORY_NEEDED (cl, hard_reg_class, mode)
4851 && ! SECONDARY_MEMORY_NEEDED (hard_reg_class, cl, mode)
4852 && TEST_HARD_REG_BIT (reg_class_contents[cl], hard_regno)
4853 && (best_cl == NO_REGS
4854 || ira_class_hard_regs_num[best_cl] < ira_class_hard_regs_num[cl]))
4855 best_cl = cl;
4856 return best_cl;
4857 #endif
4860 /* Do split transformations for insn INSN, which defines or uses
4861 ORIGINAL_REGNO. NEXT_USAGE_INSNS specifies which instruction in
4862 the EBB next uses ORIGINAL_REGNO; it has the same form as the
4863 "insns" field of usage_insns.
4865 The transformations look like:
4867 p <- ... p <- ...
4868 ... s <- p (new insn -- save)
4869 ... =>
4870 ... p <- s (new insn -- restore)
4871 <- ... p ... <- ... p ...
4873 <- ... p ... <- ... p ...
4874 ... s <- p (new insn -- save)
4875 ... =>
4876 ... p <- s (new insn -- restore)
4877 <- ... p ... <- ... p ...
4879 where p is an original pseudo got a hard register or a hard
4880 register and s is a new split pseudo. The save is put before INSN
4881 if BEFORE_P is true. Return true if we succeed in such
4882 transformation. */
4883 static bool
4884 split_reg (bool before_p, int original_regno, rtx_insn *insn,
4885 rtx next_usage_insns)
4887 enum reg_class rclass;
4888 rtx original_reg;
4889 int hard_regno, nregs;
4890 rtx new_reg, usage_insn;
4891 rtx_insn *restore, *save;
4892 bool after_p;
4893 bool call_save_p;
4895 if (original_regno < FIRST_PSEUDO_REGISTER)
4897 rclass = ira_allocno_class_translate[REGNO_REG_CLASS (original_regno)];
4898 hard_regno = original_regno;
4899 call_save_p = false;
4900 nregs = 1;
4902 else
4904 hard_regno = reg_renumber[original_regno];
4905 nregs = hard_regno_nregs[hard_regno][PSEUDO_REGNO_MODE (original_regno)];
4906 rclass = lra_get_allocno_class (original_regno);
4907 original_reg = regno_reg_rtx[original_regno];
4908 call_save_p = need_for_call_save_p (original_regno);
4910 original_reg = regno_reg_rtx[original_regno];
4911 lra_assert (hard_regno >= 0);
4912 if (lra_dump_file != NULL)
4913 fprintf (lra_dump_file,
4914 " ((((((((((((((((((((((((((((((((((((((((((((((((\n");
4915 if (call_save_p)
4917 machine_mode mode = GET_MODE (original_reg);
4919 mode = HARD_REGNO_CALLER_SAVE_MODE (hard_regno,
4920 hard_regno_nregs[hard_regno][mode],
4921 mode);
4922 new_reg = lra_create_new_reg (mode, NULL_RTX, NO_REGS, "save");
4924 else
4926 rclass = choose_split_class (rclass, hard_regno,
4927 GET_MODE (original_reg));
4928 if (rclass == NO_REGS)
4930 if (lra_dump_file != NULL)
4932 fprintf (lra_dump_file,
4933 " Rejecting split of %d(%s): "
4934 "no good reg class for %d(%s)\n",
4935 original_regno,
4936 reg_class_names[lra_get_allocno_class (original_regno)],
4937 hard_regno,
4938 reg_class_names[REGNO_REG_CLASS (hard_regno)]);
4939 fprintf
4940 (lra_dump_file,
4941 " ))))))))))))))))))))))))))))))))))))))))))))))))\n");
4943 return false;
4945 new_reg = lra_create_new_reg (GET_MODE (original_reg), original_reg,
4946 rclass, "split");
4947 reg_renumber[REGNO (new_reg)] = hard_regno;
4949 save = emit_spill_move (true, new_reg, original_reg);
4950 if (NEXT_INSN (save) != NULL_RTX && !call_save_p)
4952 if (lra_dump_file != NULL)
4954 fprintf
4955 (lra_dump_file,
4956 " Rejecting split %d->%d resulting in > 2 save insns:\n",
4957 original_regno, REGNO (new_reg));
4958 dump_rtl_slim (lra_dump_file, save, NULL, -1, 0);
4959 fprintf (lra_dump_file,
4960 " ))))))))))))))))))))))))))))))))))))))))))))))))\n");
4962 return false;
4964 restore = emit_spill_move (false, new_reg, original_reg);
4965 if (NEXT_INSN (restore) != NULL_RTX && !call_save_p)
4967 if (lra_dump_file != NULL)
4969 fprintf (lra_dump_file,
4970 " Rejecting split %d->%d "
4971 "resulting in > 2 restore insns:\n",
4972 original_regno, REGNO (new_reg));
4973 dump_rtl_slim (lra_dump_file, restore, NULL, -1, 0);
4974 fprintf (lra_dump_file,
4975 " ))))))))))))))))))))))))))))))))))))))))))))))))\n");
4977 return false;
4979 after_p = usage_insns[original_regno].after_p;
4980 lra_reg_info[REGNO (new_reg)].restore_regno = original_regno;
4981 bitmap_set_bit (&check_only_regs, REGNO (new_reg));
4982 bitmap_set_bit (&check_only_regs, original_regno);
4983 bitmap_set_bit (&lra_split_regs, REGNO (new_reg));
4984 for (;;)
4986 if (GET_CODE (next_usage_insns) != INSN_LIST)
4988 usage_insn = next_usage_insns;
4989 break;
4991 usage_insn = XEXP (next_usage_insns, 0);
4992 lra_assert (DEBUG_INSN_P (usage_insn));
4993 next_usage_insns = XEXP (next_usage_insns, 1);
4994 lra_substitute_pseudo (&usage_insn, original_regno, new_reg);
4995 lra_update_insn_regno_info (as_a <rtx_insn *> (usage_insn));
4996 if (lra_dump_file != NULL)
4998 fprintf (lra_dump_file, " Split reuse change %d->%d:\n",
4999 original_regno, REGNO (new_reg));
5000 dump_insn_slim (lra_dump_file, usage_insn);
5003 lra_assert (NOTE_P (usage_insn) || NONDEBUG_INSN_P (usage_insn));
5004 lra_assert (usage_insn != insn || (after_p && before_p));
5005 lra_process_new_insns (as_a <rtx_insn *> (usage_insn),
5006 after_p ? NULL : restore,
5007 after_p ? restore : NULL,
5008 call_save_p
5009 ? "Add reg<-save" : "Add reg<-split");
5010 lra_process_new_insns (insn, before_p ? save : NULL,
5011 before_p ? NULL : save,
5012 call_save_p
5013 ? "Add save<-reg" : "Add split<-reg");
5014 if (nregs > 1)
5015 /* If we are trying to split multi-register. We should check
5016 conflicts on the next assignment sub-pass. IRA can allocate on
5017 sub-register levels, LRA do this on pseudos level right now and
5018 this discrepancy may create allocation conflicts after
5019 splitting. */
5020 lra_risky_transformations_p = true;
5021 if (lra_dump_file != NULL)
5022 fprintf (lra_dump_file,
5023 " ))))))))))))))))))))))))))))))))))))))))))))))))\n");
5024 return true;
5027 /* Recognize that we need a split transformation for insn INSN, which
5028 defines or uses REGNO in its insn biggest MODE (we use it only if
5029 REGNO is a hard register). POTENTIAL_RELOAD_HARD_REGS contains
5030 hard registers which might be used for reloads since the EBB end.
5031 Put the save before INSN if BEFORE_P is true. MAX_UID is maximla
5032 uid before starting INSN processing. Return true if we succeed in
5033 such transformation. */
5034 static bool
5035 split_if_necessary (int regno, machine_mode mode,
5036 HARD_REG_SET potential_reload_hard_regs,
5037 bool before_p, rtx_insn *insn, int max_uid)
5039 bool res = false;
5040 int i, nregs = 1;
5041 rtx next_usage_insns;
5043 if (regno < FIRST_PSEUDO_REGISTER)
5044 nregs = hard_regno_nregs[regno][mode];
5045 for (i = 0; i < nregs; i++)
5046 if (usage_insns[regno + i].check == curr_usage_insns_check
5047 && (next_usage_insns = usage_insns[regno + i].insns) != NULL_RTX
5048 /* To avoid processing the register twice or more. */
5049 && ((GET_CODE (next_usage_insns) != INSN_LIST
5050 && INSN_UID (next_usage_insns) < max_uid)
5051 || (GET_CODE (next_usage_insns) == INSN_LIST
5052 && (INSN_UID (XEXP (next_usage_insns, 0)) < max_uid)))
5053 && need_for_split_p (potential_reload_hard_regs, regno + i)
5054 && split_reg (before_p, regno + i, insn, next_usage_insns))
5055 res = true;
5056 return res;
5059 /* Check only registers living at the current program point in the
5060 current EBB. */
5061 static bitmap_head live_regs;
5063 /* Update live info in EBB given by its HEAD and TAIL insns after
5064 inheritance/split transformation. The function removes dead moves
5065 too. */
5066 static void
5067 update_ebb_live_info (rtx_insn *head, rtx_insn *tail)
5069 unsigned int j;
5070 int i, regno;
5071 bool live_p;
5072 rtx_insn *prev_insn;
5073 rtx set;
5074 bool remove_p;
5075 basic_block last_bb, prev_bb, curr_bb;
5076 bitmap_iterator bi;
5077 struct lra_insn_reg *reg;
5078 edge e;
5079 edge_iterator ei;
5081 last_bb = BLOCK_FOR_INSN (tail);
5082 prev_bb = NULL;
5083 for (curr_insn = tail;
5084 curr_insn != PREV_INSN (head);
5085 curr_insn = prev_insn)
5087 prev_insn = PREV_INSN (curr_insn);
5088 /* We need to process empty blocks too. They contain
5089 NOTE_INSN_BASIC_BLOCK referring for the basic block. */
5090 if (NOTE_P (curr_insn) && NOTE_KIND (curr_insn) != NOTE_INSN_BASIC_BLOCK)
5091 continue;
5092 curr_bb = BLOCK_FOR_INSN (curr_insn);
5093 if (curr_bb != prev_bb)
5095 if (prev_bb != NULL)
5097 /* Update df_get_live_in (prev_bb): */
5098 EXECUTE_IF_SET_IN_BITMAP (&check_only_regs, 0, j, bi)
5099 if (bitmap_bit_p (&live_regs, j))
5100 bitmap_set_bit (df_get_live_in (prev_bb), j);
5101 else
5102 bitmap_clear_bit (df_get_live_in (prev_bb), j);
5104 if (curr_bb != last_bb)
5106 /* Update df_get_live_out (curr_bb): */
5107 EXECUTE_IF_SET_IN_BITMAP (&check_only_regs, 0, j, bi)
5109 live_p = bitmap_bit_p (&live_regs, j);
5110 if (! live_p)
5111 FOR_EACH_EDGE (e, ei, curr_bb->succs)
5112 if (bitmap_bit_p (df_get_live_in (e->dest), j))
5114 live_p = true;
5115 break;
5117 if (live_p)
5118 bitmap_set_bit (df_get_live_out (curr_bb), j);
5119 else
5120 bitmap_clear_bit (df_get_live_out (curr_bb), j);
5123 prev_bb = curr_bb;
5124 bitmap_and (&live_regs, &check_only_regs, df_get_live_out (curr_bb));
5126 if (! NONDEBUG_INSN_P (curr_insn))
5127 continue;
5128 curr_id = lra_get_insn_recog_data (curr_insn);
5129 curr_static_id = curr_id->insn_static_data;
5130 remove_p = false;
5131 if ((set = single_set (curr_insn)) != NULL_RTX && REG_P (SET_DEST (set))
5132 && (regno = REGNO (SET_DEST (set))) >= FIRST_PSEUDO_REGISTER
5133 && bitmap_bit_p (&check_only_regs, regno)
5134 && ! bitmap_bit_p (&live_regs, regno))
5135 remove_p = true;
5136 /* See which defined values die here. */
5137 for (reg = curr_id->regs; reg != NULL; reg = reg->next)
5138 if (reg->type == OP_OUT && ! reg->subreg_p)
5139 bitmap_clear_bit (&live_regs, reg->regno);
5140 for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next)
5141 if (reg->type == OP_OUT && ! reg->subreg_p)
5142 bitmap_clear_bit (&live_regs, reg->regno);
5143 /* Mark each used value as live. */
5144 for (reg = curr_id->regs; reg != NULL; reg = reg->next)
5145 if (reg->type != OP_OUT
5146 && bitmap_bit_p (&check_only_regs, reg->regno))
5147 bitmap_set_bit (&live_regs, reg->regno);
5148 for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next)
5149 if (reg->type != OP_OUT
5150 && bitmap_bit_p (&check_only_regs, reg->regno))
5151 bitmap_set_bit (&live_regs, reg->regno);
5152 if (curr_id->arg_hard_regs != NULL)
5153 /* Make argument hard registers live. */
5154 for (i = 0; (regno = curr_id->arg_hard_regs[i]) >= 0; i++)
5155 if (bitmap_bit_p (&check_only_regs, regno))
5156 bitmap_set_bit (&live_regs, regno);
5157 /* It is quite important to remove dead move insns because it
5158 means removing dead store. We don't need to process them for
5159 constraints. */
5160 if (remove_p)
5162 if (lra_dump_file != NULL)
5164 fprintf (lra_dump_file, " Removing dead insn:\n ");
5165 dump_insn_slim (lra_dump_file, curr_insn);
5167 lra_set_insn_deleted (curr_insn);
5172 /* The structure describes info to do an inheritance for the current
5173 insn. We need to collect such info first before doing the
5174 transformations because the transformations change the insn
5175 internal representation. */
5176 struct to_inherit
5178 /* Original regno. */
5179 int regno;
5180 /* Subsequent insns which can inherit original reg value. */
5181 rtx insns;
5184 /* Array containing all info for doing inheritance from the current
5185 insn. */
5186 static struct to_inherit to_inherit[LRA_MAX_INSN_RELOADS];
5188 /* Number elements in the previous array. */
5189 static int to_inherit_num;
5191 /* Add inheritance info REGNO and INSNS. Their meaning is described in
5192 structure to_inherit. */
5193 static void
5194 add_to_inherit (int regno, rtx insns)
5196 int i;
5198 for (i = 0; i < to_inherit_num; i++)
5199 if (to_inherit[i].regno == regno)
5200 return;
5201 lra_assert (to_inherit_num < LRA_MAX_INSN_RELOADS);
5202 to_inherit[to_inherit_num].regno = regno;
5203 to_inherit[to_inherit_num++].insns = insns;
5206 /* Return the last non-debug insn in basic block BB, or the block begin
5207 note if none. */
5208 static rtx_insn *
5209 get_last_insertion_point (basic_block bb)
5211 rtx_insn *insn;
5213 FOR_BB_INSNS_REVERSE (bb, insn)
5214 if (NONDEBUG_INSN_P (insn) || NOTE_INSN_BASIC_BLOCK_P (insn))
5215 return insn;
5216 gcc_unreachable ();
5219 /* Set up RES by registers living on edges FROM except the edge (FROM,
5220 TO) or by registers set up in a jump insn in BB FROM. */
5221 static void
5222 get_live_on_other_edges (basic_block from, basic_block to, bitmap res)
5224 rtx_insn *last;
5225 struct lra_insn_reg *reg;
5226 edge e;
5227 edge_iterator ei;
5229 lra_assert (to != NULL);
5230 bitmap_clear (res);
5231 FOR_EACH_EDGE (e, ei, from->succs)
5232 if (e->dest != to)
5233 bitmap_ior_into (res, df_get_live_in (e->dest));
5234 last = get_last_insertion_point (from);
5235 if (! JUMP_P (last))
5236 return;
5237 curr_id = lra_get_insn_recog_data (last);
5238 for (reg = curr_id->regs; reg != NULL; reg = reg->next)
5239 if (reg->type != OP_IN)
5240 bitmap_set_bit (res, reg->regno);
5243 /* Used as a temporary results of some bitmap calculations. */
5244 static bitmap_head temp_bitmap;
5246 /* We split for reloads of small class of hard regs. The following
5247 defines how many hard regs the class should have to be qualified as
5248 small. The code is mostly oriented to x86/x86-64 architecture
5249 where some insns need to use only specific register or pair of
5250 registers and these register can live in RTL explicitly, e.g. for
5251 parameter passing. */
5252 static const int max_small_class_regs_num = 2;
5254 /* Do inheritance/split transformations in EBB starting with HEAD and
5255 finishing on TAIL. We process EBB insns in the reverse order.
5256 Return true if we did any inheritance/split transformation in the
5257 EBB.
5259 We should avoid excessive splitting which results in worse code
5260 because of inaccurate cost calculations for spilling new split
5261 pseudos in such case. To achieve this we do splitting only if
5262 register pressure is high in given basic block and there are reload
5263 pseudos requiring hard registers. We could do more register
5264 pressure calculations at any given program point to avoid necessary
5265 splitting even more but it is to expensive and the current approach
5266 works well enough. */
5267 static bool
5268 inherit_in_ebb (rtx_insn *head, rtx_insn *tail)
5270 int i, src_regno, dst_regno, nregs;
5271 bool change_p, succ_p, update_reloads_num_p;
5272 rtx_insn *prev_insn, *last_insn;
5273 rtx next_usage_insns, set;
5274 enum reg_class cl;
5275 struct lra_insn_reg *reg;
5276 basic_block last_processed_bb, curr_bb = NULL;
5277 HARD_REG_SET potential_reload_hard_regs, live_hard_regs;
5278 bitmap to_process;
5279 unsigned int j;
5280 bitmap_iterator bi;
5281 bool head_p, after_p;
5283 change_p = false;
5284 curr_usage_insns_check++;
5285 reloads_num = calls_num = 0;
5286 bitmap_clear (&check_only_regs);
5287 last_processed_bb = NULL;
5288 CLEAR_HARD_REG_SET (potential_reload_hard_regs);
5289 COPY_HARD_REG_SET (live_hard_regs, eliminable_regset);
5290 IOR_HARD_REG_SET (live_hard_regs, lra_no_alloc_regs);
5291 /* We don't process new insns generated in the loop. */
5292 for (curr_insn = tail; curr_insn != PREV_INSN (head); curr_insn = prev_insn)
5294 prev_insn = PREV_INSN (curr_insn);
5295 if (BLOCK_FOR_INSN (curr_insn) != NULL)
5296 curr_bb = BLOCK_FOR_INSN (curr_insn);
5297 if (last_processed_bb != curr_bb)
5299 /* We are at the end of BB. Add qualified living
5300 pseudos for potential splitting. */
5301 to_process = df_get_live_out (curr_bb);
5302 if (last_processed_bb != NULL)
5304 /* We are somewhere in the middle of EBB. */
5305 get_live_on_other_edges (curr_bb, last_processed_bb,
5306 &temp_bitmap);
5307 to_process = &temp_bitmap;
5309 last_processed_bb = curr_bb;
5310 last_insn = get_last_insertion_point (curr_bb);
5311 after_p = (! JUMP_P (last_insn)
5312 && (! CALL_P (last_insn)
5313 || (find_reg_note (last_insn,
5314 REG_NORETURN, NULL_RTX) == NULL_RTX
5315 && ! SIBLING_CALL_P (last_insn))));
5316 CLEAR_HARD_REG_SET (potential_reload_hard_regs);
5317 EXECUTE_IF_SET_IN_BITMAP (to_process, 0, j, bi)
5319 if ((int) j >= lra_constraint_new_regno_start)
5320 break;
5321 if (j < FIRST_PSEUDO_REGISTER || reg_renumber[j] >= 0)
5323 if (j < FIRST_PSEUDO_REGISTER)
5324 SET_HARD_REG_BIT (live_hard_regs, j);
5325 else
5326 add_to_hard_reg_set (&live_hard_regs,
5327 PSEUDO_REGNO_MODE (j),
5328 reg_renumber[j]);
5329 setup_next_usage_insn (j, last_insn, reloads_num, after_p);
5333 src_regno = dst_regno = -1;
5334 if (NONDEBUG_INSN_P (curr_insn)
5335 && (set = single_set (curr_insn)) != NULL_RTX
5336 && REG_P (SET_DEST (set)) && REG_P (SET_SRC (set)))
5338 src_regno = REGNO (SET_SRC (set));
5339 dst_regno = REGNO (SET_DEST (set));
5341 update_reloads_num_p = true;
5342 if (src_regno < lra_constraint_new_regno_start
5343 && src_regno >= FIRST_PSEUDO_REGISTER
5344 && reg_renumber[src_regno] < 0
5345 && dst_regno >= lra_constraint_new_regno_start
5346 && (cl = lra_get_allocno_class (dst_regno)) != NO_REGS)
5348 /* 'reload_pseudo <- original_pseudo'. */
5349 if (ira_class_hard_regs_num[cl] <= max_small_class_regs_num)
5350 reloads_num++;
5351 update_reloads_num_p = false;
5352 succ_p = false;
5353 if (usage_insns[src_regno].check == curr_usage_insns_check
5354 && (next_usage_insns = usage_insns[src_regno].insns) != NULL_RTX)
5355 succ_p = inherit_reload_reg (false, src_regno, cl,
5356 curr_insn, next_usage_insns);
5357 if (succ_p)
5358 change_p = true;
5359 else
5360 setup_next_usage_insn (src_regno, curr_insn, reloads_num, false);
5361 if (hard_reg_set_subset_p (reg_class_contents[cl], live_hard_regs))
5362 IOR_HARD_REG_SET (potential_reload_hard_regs,
5363 reg_class_contents[cl]);
5365 else if (src_regno >= lra_constraint_new_regno_start
5366 && dst_regno < lra_constraint_new_regno_start
5367 && dst_regno >= FIRST_PSEUDO_REGISTER
5368 && reg_renumber[dst_regno] < 0
5369 && (cl = lra_get_allocno_class (src_regno)) != NO_REGS
5370 && usage_insns[dst_regno].check == curr_usage_insns_check
5371 && (next_usage_insns
5372 = usage_insns[dst_regno].insns) != NULL_RTX)
5374 if (ira_class_hard_regs_num[cl] <= max_small_class_regs_num)
5375 reloads_num++;
5376 update_reloads_num_p = false;
5377 /* 'original_pseudo <- reload_pseudo'. */
5378 if (! JUMP_P (curr_insn)
5379 && inherit_reload_reg (true, dst_regno, cl,
5380 curr_insn, next_usage_insns))
5381 change_p = true;
5382 /* Invalidate. */
5383 usage_insns[dst_regno].check = 0;
5384 if (hard_reg_set_subset_p (reg_class_contents[cl], live_hard_regs))
5385 IOR_HARD_REG_SET (potential_reload_hard_regs,
5386 reg_class_contents[cl]);
5388 else if (INSN_P (curr_insn))
5390 int iter;
5391 int max_uid = get_max_uid ();
5393 curr_id = lra_get_insn_recog_data (curr_insn);
5394 curr_static_id = curr_id->insn_static_data;
5395 to_inherit_num = 0;
5396 /* Process insn definitions. */
5397 for (iter = 0; iter < 2; iter++)
5398 for (reg = iter == 0 ? curr_id->regs : curr_static_id->hard_regs;
5399 reg != NULL;
5400 reg = reg->next)
5401 if (reg->type != OP_IN
5402 && (dst_regno = reg->regno) < lra_constraint_new_regno_start)
5404 if (dst_regno >= FIRST_PSEUDO_REGISTER && reg->type == OP_OUT
5405 && reg_renumber[dst_regno] < 0 && ! reg->subreg_p
5406 && usage_insns[dst_regno].check == curr_usage_insns_check
5407 && (next_usage_insns
5408 = usage_insns[dst_regno].insns) != NULL_RTX)
5410 struct lra_insn_reg *r;
5412 for (r = curr_id->regs; r != NULL; r = r->next)
5413 if (r->type != OP_OUT && r->regno == dst_regno)
5414 break;
5415 /* Don't do inheritance if the pseudo is also
5416 used in the insn. */
5417 if (r == NULL)
5418 /* We can not do inheritance right now
5419 because the current insn reg info (chain
5420 regs) can change after that. */
5421 add_to_inherit (dst_regno, next_usage_insns);
5423 /* We can not process one reg twice here because of
5424 usage_insns invalidation. */
5425 if ((dst_regno < FIRST_PSEUDO_REGISTER
5426 || reg_renumber[dst_regno] >= 0)
5427 && ! reg->subreg_p && reg->type != OP_IN)
5429 HARD_REG_SET s;
5431 if (split_if_necessary (dst_regno, reg->biggest_mode,
5432 potential_reload_hard_regs,
5433 false, curr_insn, max_uid))
5434 change_p = true;
5435 CLEAR_HARD_REG_SET (s);
5436 if (dst_regno < FIRST_PSEUDO_REGISTER)
5437 add_to_hard_reg_set (&s, reg->biggest_mode, dst_regno);
5438 else
5439 add_to_hard_reg_set (&s, PSEUDO_REGNO_MODE (dst_regno),
5440 reg_renumber[dst_regno]);
5441 AND_COMPL_HARD_REG_SET (live_hard_regs, s);
5443 /* We should invalidate potential inheritance or
5444 splitting for the current insn usages to the next
5445 usage insns (see code below) as the output pseudo
5446 prevents this. */
5447 if ((dst_regno >= FIRST_PSEUDO_REGISTER
5448 && reg_renumber[dst_regno] < 0)
5449 || (reg->type == OP_OUT && ! reg->subreg_p
5450 && (dst_regno < FIRST_PSEUDO_REGISTER
5451 || reg_renumber[dst_regno] >= 0)))
5453 /* Invalidate and mark definitions. */
5454 if (dst_regno >= FIRST_PSEUDO_REGISTER)
5455 usage_insns[dst_regno].check = -(int) INSN_UID (curr_insn);
5456 else
5458 nregs = hard_regno_nregs[dst_regno][reg->biggest_mode];
5459 for (i = 0; i < nregs; i++)
5460 usage_insns[dst_regno + i].check
5461 = -(int) INSN_UID (curr_insn);
5465 if (! JUMP_P (curr_insn))
5466 for (i = 0; i < to_inherit_num; i++)
5467 if (inherit_reload_reg (true, to_inherit[i].regno,
5468 ALL_REGS, curr_insn,
5469 to_inherit[i].insns))
5470 change_p = true;
5471 if (CALL_P (curr_insn))
5473 rtx cheap, pat, dest;
5474 rtx_insn *restore;
5475 int regno, hard_regno;
5477 calls_num++;
5478 if ((cheap = find_reg_note (curr_insn,
5479 REG_RETURNED, NULL_RTX)) != NULL_RTX
5480 && ((cheap = XEXP (cheap, 0)), true)
5481 && (regno = REGNO (cheap)) >= FIRST_PSEUDO_REGISTER
5482 && (hard_regno = reg_renumber[regno]) >= 0
5483 /* If there are pending saves/restores, the
5484 optimization is not worth. */
5485 && usage_insns[regno].calls_num == calls_num - 1
5486 && TEST_HARD_REG_BIT (call_used_reg_set, hard_regno))
5488 /* Restore the pseudo from the call result as
5489 REG_RETURNED note says that the pseudo value is
5490 in the call result and the pseudo is an argument
5491 of the call. */
5492 pat = PATTERN (curr_insn);
5493 if (GET_CODE (pat) == PARALLEL)
5494 pat = XVECEXP (pat, 0, 0);
5495 dest = SET_DEST (pat);
5496 /* For multiple return values dest is PARALLEL.
5497 Currently we handle only single return value case. */
5498 if (REG_P (dest))
5500 start_sequence ();
5501 emit_move_insn (cheap, copy_rtx (dest));
5502 restore = get_insns ();
5503 end_sequence ();
5504 lra_process_new_insns (curr_insn, NULL, restore,
5505 "Inserting call parameter restore");
5506 /* We don't need to save/restore of the pseudo from
5507 this call. */
5508 usage_insns[regno].calls_num = calls_num;
5509 bitmap_set_bit (&check_only_regs, regno);
5513 to_inherit_num = 0;
5514 /* Process insn usages. */
5515 for (iter = 0; iter < 2; iter++)
5516 for (reg = iter == 0 ? curr_id->regs : curr_static_id->hard_regs;
5517 reg != NULL;
5518 reg = reg->next)
5519 if ((reg->type != OP_OUT
5520 || (reg->type == OP_OUT && reg->subreg_p))
5521 && (src_regno = reg->regno) < lra_constraint_new_regno_start)
5523 if (src_regno >= FIRST_PSEUDO_REGISTER
5524 && reg_renumber[src_regno] < 0 && reg->type == OP_IN)
5526 if (usage_insns[src_regno].check == curr_usage_insns_check
5527 && (next_usage_insns
5528 = usage_insns[src_regno].insns) != NULL_RTX
5529 && NONDEBUG_INSN_P (curr_insn))
5530 add_to_inherit (src_regno, next_usage_insns);
5531 else if (usage_insns[src_regno].check
5532 != -(int) INSN_UID (curr_insn))
5533 /* Add usages but only if the reg is not set up
5534 in the same insn. */
5535 add_next_usage_insn (src_regno, curr_insn, reloads_num);
5537 else if (src_regno < FIRST_PSEUDO_REGISTER
5538 || reg_renumber[src_regno] >= 0)
5540 bool before_p;
5541 rtx use_insn = curr_insn;
5543 before_p = (JUMP_P (curr_insn)
5544 || (CALL_P (curr_insn) && reg->type == OP_IN));
5545 if (NONDEBUG_INSN_P (curr_insn)
5546 && (! JUMP_P (curr_insn) || reg->type == OP_IN)
5547 && split_if_necessary (src_regno, reg->biggest_mode,
5548 potential_reload_hard_regs,
5549 before_p, curr_insn, max_uid))
5551 if (reg->subreg_p)
5552 lra_risky_transformations_p = true;
5553 change_p = true;
5554 /* Invalidate. */
5555 usage_insns[src_regno].check = 0;
5556 if (before_p)
5557 use_insn = PREV_INSN (curr_insn);
5559 if (NONDEBUG_INSN_P (curr_insn))
5561 if (src_regno < FIRST_PSEUDO_REGISTER)
5562 add_to_hard_reg_set (&live_hard_regs,
5563 reg->biggest_mode, src_regno);
5564 else
5565 add_to_hard_reg_set (&live_hard_regs,
5566 PSEUDO_REGNO_MODE (src_regno),
5567 reg_renumber[src_regno]);
5569 add_next_usage_insn (src_regno, use_insn, reloads_num);
5572 /* Process call args. */
5573 if (curr_id->arg_hard_regs != NULL)
5574 for (i = 0; (src_regno = curr_id->arg_hard_regs[i]) >= 0; i++)
5575 if (src_regno < FIRST_PSEUDO_REGISTER)
5577 SET_HARD_REG_BIT (live_hard_regs, src_regno);
5578 add_next_usage_insn (src_regno, curr_insn, reloads_num);
5580 for (i = 0; i < to_inherit_num; i++)
5582 src_regno = to_inherit[i].regno;
5583 if (inherit_reload_reg (false, src_regno, ALL_REGS,
5584 curr_insn, to_inherit[i].insns))
5585 change_p = true;
5586 else
5587 setup_next_usage_insn (src_regno, curr_insn, reloads_num, false);
5590 if (update_reloads_num_p
5591 && NONDEBUG_INSN_P (curr_insn)
5592 && (set = single_set (curr_insn)) != NULL_RTX)
5594 int regno = -1;
5595 if ((REG_P (SET_DEST (set))
5596 && (regno = REGNO (SET_DEST (set))) >= lra_constraint_new_regno_start
5597 && reg_renumber[regno] < 0
5598 && (cl = lra_get_allocno_class (regno)) != NO_REGS)
5599 || (REG_P (SET_SRC (set))
5600 && (regno = REGNO (SET_SRC (set))) >= lra_constraint_new_regno_start
5601 && reg_renumber[regno] < 0
5602 && (cl = lra_get_allocno_class (regno)) != NO_REGS))
5604 if (ira_class_hard_regs_num[cl] <= max_small_class_regs_num)
5605 reloads_num++;
5606 if (hard_reg_set_subset_p (reg_class_contents[cl], live_hard_regs))
5607 IOR_HARD_REG_SET (potential_reload_hard_regs,
5608 reg_class_contents[cl]);
5611 /* We reached the start of the current basic block. */
5612 if (prev_insn == NULL_RTX || prev_insn == PREV_INSN (head)
5613 || BLOCK_FOR_INSN (prev_insn) != curr_bb)
5615 /* We reached the beginning of the current block -- do
5616 rest of spliting in the current BB. */
5617 to_process = df_get_live_in (curr_bb);
5618 if (BLOCK_FOR_INSN (head) != curr_bb)
5620 /* We are somewhere in the middle of EBB. */
5621 get_live_on_other_edges (EDGE_PRED (curr_bb, 0)->src,
5622 curr_bb, &temp_bitmap);
5623 to_process = &temp_bitmap;
5625 head_p = true;
5626 EXECUTE_IF_SET_IN_BITMAP (to_process, 0, j, bi)
5628 if ((int) j >= lra_constraint_new_regno_start)
5629 break;
5630 if (((int) j < FIRST_PSEUDO_REGISTER || reg_renumber[j] >= 0)
5631 && usage_insns[j].check == curr_usage_insns_check
5632 && (next_usage_insns = usage_insns[j].insns) != NULL_RTX)
5634 if (need_for_split_p (potential_reload_hard_regs, j))
5636 if (lra_dump_file != NULL && head_p)
5638 fprintf (lra_dump_file,
5639 " ----------------------------------\n");
5640 head_p = false;
5642 if (split_reg (false, j, bb_note (curr_bb),
5643 next_usage_insns))
5644 change_p = true;
5646 usage_insns[j].check = 0;
5651 return change_p;
5654 /* This value affects EBB forming. If probability of edge from EBB to
5655 a BB is not greater than the following value, we don't add the BB
5656 to EBB. */
5657 #define EBB_PROBABILITY_CUTOFF ((REG_BR_PROB_BASE * 50) / 100)
5659 /* Current number of inheritance/split iteration. */
5660 int lra_inheritance_iter;
5662 /* Entry function for inheritance/split pass. */
5663 void
5664 lra_inheritance (void)
5666 int i;
5667 basic_block bb, start_bb;
5668 edge e;
5670 lra_inheritance_iter++;
5671 if (lra_inheritance_iter > LRA_MAX_INHERITANCE_PASSES)
5672 return;
5673 timevar_push (TV_LRA_INHERITANCE);
5674 if (lra_dump_file != NULL)
5675 fprintf (lra_dump_file, "\n********** Inheritance #%d: **********\n\n",
5676 lra_inheritance_iter);
5677 curr_usage_insns_check = 0;
5678 usage_insns = XNEWVEC (struct usage_insns, lra_constraint_new_regno_start);
5679 for (i = 0; i < lra_constraint_new_regno_start; i++)
5680 usage_insns[i].check = 0;
5681 bitmap_initialize (&check_only_regs, &reg_obstack);
5682 bitmap_initialize (&live_regs, &reg_obstack);
5683 bitmap_initialize (&temp_bitmap, &reg_obstack);
5684 bitmap_initialize (&ebb_global_regs, &reg_obstack);
5685 FOR_EACH_BB_FN (bb, cfun)
5687 start_bb = bb;
5688 if (lra_dump_file != NULL)
5689 fprintf (lra_dump_file, "EBB");
5690 /* Form a EBB starting with BB. */
5691 bitmap_clear (&ebb_global_regs);
5692 bitmap_ior_into (&ebb_global_regs, df_get_live_in (bb));
5693 for (;;)
5695 if (lra_dump_file != NULL)
5696 fprintf (lra_dump_file, " %d", bb->index);
5697 if (bb->next_bb == EXIT_BLOCK_PTR_FOR_FN (cfun)
5698 || LABEL_P (BB_HEAD (bb->next_bb)))
5699 break;
5700 e = find_fallthru_edge (bb->succs);
5701 if (! e)
5702 break;
5703 if (e->probability <= EBB_PROBABILITY_CUTOFF)
5704 break;
5705 bb = bb->next_bb;
5707 bitmap_ior_into (&ebb_global_regs, df_get_live_out (bb));
5708 if (lra_dump_file != NULL)
5709 fprintf (lra_dump_file, "\n");
5710 if (inherit_in_ebb (BB_HEAD (start_bb), BB_END (bb)))
5711 /* Remember that the EBB head and tail can change in
5712 inherit_in_ebb. */
5713 update_ebb_live_info (BB_HEAD (start_bb), BB_END (bb));
5715 bitmap_clear (&ebb_global_regs);
5716 bitmap_clear (&temp_bitmap);
5717 bitmap_clear (&live_regs);
5718 bitmap_clear (&check_only_regs);
5719 free (usage_insns);
5721 timevar_pop (TV_LRA_INHERITANCE);
5726 /* This page contains code to undo failed inheritance/split
5727 transformations. */
5729 /* Current number of iteration undoing inheritance/split. */
5730 int lra_undo_inheritance_iter;
5732 /* Fix BB live info LIVE after removing pseudos created on pass doing
5733 inheritance/split which are REMOVED_PSEUDOS. */
5734 static void
5735 fix_bb_live_info (bitmap live, bitmap removed_pseudos)
5737 unsigned int regno;
5738 bitmap_iterator bi;
5740 EXECUTE_IF_SET_IN_BITMAP (removed_pseudos, 0, regno, bi)
5741 if (bitmap_clear_bit (live, regno))
5742 bitmap_set_bit (live, lra_reg_info[regno].restore_regno);
5745 /* Return regno of the (subreg of) REG. Otherwise, return a negative
5746 number. */
5747 static int
5748 get_regno (rtx reg)
5750 if (GET_CODE (reg) == SUBREG)
5751 reg = SUBREG_REG (reg);
5752 if (REG_P (reg))
5753 return REGNO (reg);
5754 return -1;
5757 /* Remove inheritance/split pseudos which are in REMOVE_PSEUDOS and
5758 return true if we did any change. The undo transformations for
5759 inheritance looks like
5760 i <- i2
5761 p <- i => p <- i2
5762 or removing
5763 p <- i, i <- p, and i <- i3
5764 where p is original pseudo from which inheritance pseudo i was
5765 created, i and i3 are removed inheritance pseudos, i2 is another
5766 not removed inheritance pseudo. All split pseudos or other
5767 occurrences of removed inheritance pseudos are changed on the
5768 corresponding original pseudos.
5770 The function also schedules insns changed and created during
5771 inheritance/split pass for processing by the subsequent constraint
5772 pass. */
5773 static bool
5774 remove_inheritance_pseudos (bitmap remove_pseudos)
5776 basic_block bb;
5777 int regno, sregno, prev_sregno, dregno, restore_regno;
5778 rtx set, prev_set;
5779 rtx_insn *prev_insn;
5780 bool change_p, done_p;
5782 change_p = ! bitmap_empty_p (remove_pseudos);
5783 /* We can not finish the function right away if CHANGE_P is true
5784 because we need to marks insns affected by previous
5785 inheritance/split pass for processing by the subsequent
5786 constraint pass. */
5787 FOR_EACH_BB_FN (bb, cfun)
5789 fix_bb_live_info (df_get_live_in (bb), remove_pseudos);
5790 fix_bb_live_info (df_get_live_out (bb), remove_pseudos);
5791 FOR_BB_INSNS_REVERSE (bb, curr_insn)
5793 if (! INSN_P (curr_insn))
5794 continue;
5795 done_p = false;
5796 sregno = dregno = -1;
5797 if (change_p && NONDEBUG_INSN_P (curr_insn)
5798 && (set = single_set (curr_insn)) != NULL_RTX)
5800 dregno = get_regno (SET_DEST (set));
5801 sregno = get_regno (SET_SRC (set));
5804 if (sregno >= 0 && dregno >= 0)
5806 if ((bitmap_bit_p (remove_pseudos, sregno)
5807 && (lra_reg_info[sregno].restore_regno == dregno
5808 || (bitmap_bit_p (remove_pseudos, dregno)
5809 && (lra_reg_info[sregno].restore_regno
5810 == lra_reg_info[dregno].restore_regno))))
5811 || (bitmap_bit_p (remove_pseudos, dregno)
5812 && lra_reg_info[dregno].restore_regno == sregno))
5813 /* One of the following cases:
5814 original <- removed inheritance pseudo
5815 removed inherit pseudo <- another removed inherit pseudo
5816 removed inherit pseudo <- original pseudo
5818 removed_split_pseudo <- original_reg
5819 original_reg <- removed_split_pseudo */
5821 if (lra_dump_file != NULL)
5823 fprintf (lra_dump_file, " Removing %s:\n",
5824 bitmap_bit_p (&lra_split_regs, sregno)
5825 || bitmap_bit_p (&lra_split_regs, dregno)
5826 ? "split" : "inheritance");
5827 dump_insn_slim (lra_dump_file, curr_insn);
5829 lra_set_insn_deleted (curr_insn);
5830 done_p = true;
5832 else if (bitmap_bit_p (remove_pseudos, sregno)
5833 && bitmap_bit_p (&lra_inheritance_pseudos, sregno))
5835 /* Search the following pattern:
5836 inherit_or_split_pseudo1 <- inherit_or_split_pseudo2
5837 original_pseudo <- inherit_or_split_pseudo1
5838 where the 2nd insn is the current insn and
5839 inherit_or_split_pseudo2 is not removed. If it is found,
5840 change the current insn onto:
5841 original_pseudo <- inherit_or_split_pseudo2. */
5842 for (prev_insn = PREV_INSN (curr_insn);
5843 prev_insn != NULL_RTX && ! NONDEBUG_INSN_P (prev_insn);
5844 prev_insn = PREV_INSN (prev_insn))
5846 if (prev_insn != NULL_RTX && BLOCK_FOR_INSN (prev_insn) == bb
5847 && (prev_set = single_set (prev_insn)) != NULL_RTX
5848 /* There should be no subregs in insn we are
5849 searching because only the original reg might
5850 be in subreg when we changed the mode of
5851 load/store for splitting. */
5852 && REG_P (SET_DEST (prev_set))
5853 && REG_P (SET_SRC (prev_set))
5854 && (int) REGNO (SET_DEST (prev_set)) == sregno
5855 && ((prev_sregno = REGNO (SET_SRC (prev_set)))
5856 >= FIRST_PSEUDO_REGISTER)
5857 /* As we consider chain of inheritance or
5858 splitting described in above comment we should
5859 check that sregno and prev_sregno were
5860 inheritance/split pseudos created from the
5861 same original regno. */
5862 && (lra_reg_info[sregno].restore_regno
5863 == lra_reg_info[prev_sregno].restore_regno)
5864 && ! bitmap_bit_p (remove_pseudos, prev_sregno))
5866 lra_assert (GET_MODE (SET_SRC (prev_set))
5867 == GET_MODE (regno_reg_rtx[sregno]));
5868 if (GET_CODE (SET_SRC (set)) == SUBREG)
5869 SUBREG_REG (SET_SRC (set)) = SET_SRC (prev_set);
5870 else
5871 SET_SRC (set) = SET_SRC (prev_set);
5872 /* As we are finishing with processing the insn
5873 here, check the destination too as it might
5874 inheritance pseudo for another pseudo. */
5875 if (bitmap_bit_p (remove_pseudos, dregno)
5876 && bitmap_bit_p (&lra_inheritance_pseudos, dregno)
5877 && (restore_regno
5878 = lra_reg_info[dregno].restore_regno) >= 0)
5880 if (GET_CODE (SET_DEST (set)) == SUBREG)
5881 SUBREG_REG (SET_DEST (set))
5882 = regno_reg_rtx[restore_regno];
5883 else
5884 SET_DEST (set) = regno_reg_rtx[restore_regno];
5886 lra_push_insn_and_update_insn_regno_info (curr_insn);
5887 lra_set_used_insn_alternative_by_uid
5888 (INSN_UID (curr_insn), -1);
5889 done_p = true;
5890 if (lra_dump_file != NULL)
5892 fprintf (lra_dump_file, " Change reload insn:\n");
5893 dump_insn_slim (lra_dump_file, curr_insn);
5898 if (! done_p)
5900 struct lra_insn_reg *reg;
5901 bool restored_regs_p = false;
5902 bool kept_regs_p = false;
5904 curr_id = lra_get_insn_recog_data (curr_insn);
5905 for (reg = curr_id->regs; reg != NULL; reg = reg->next)
5907 regno = reg->regno;
5908 restore_regno = lra_reg_info[regno].restore_regno;
5909 if (restore_regno >= 0)
5911 if (change_p && bitmap_bit_p (remove_pseudos, regno))
5913 lra_substitute_pseudo_within_insn (
5914 curr_insn, regno, regno_reg_rtx[restore_regno]);
5915 restored_regs_p = true;
5917 else
5918 kept_regs_p = true;
5921 if (NONDEBUG_INSN_P (curr_insn) && kept_regs_p)
5923 /* The instruction has changed since the previous
5924 constraints pass. */
5925 lra_push_insn_and_update_insn_regno_info (curr_insn);
5926 lra_set_used_insn_alternative_by_uid
5927 (INSN_UID (curr_insn), -1);
5929 else if (restored_regs_p)
5930 /* The instruction has been restored to the form that
5931 it had during the previous constraints pass. */
5932 lra_update_insn_regno_info (curr_insn);
5933 if (restored_regs_p && lra_dump_file != NULL)
5935 fprintf (lra_dump_file, " Insn after restoring regs:\n");
5936 dump_insn_slim (lra_dump_file, curr_insn);
5941 return change_p;
5944 /* If optional reload pseudos failed to get a hard register or was not
5945 inherited, it is better to remove optional reloads. We do this
5946 transformation after undoing inheritance to figure out necessity to
5947 remove optional reloads easier. Return true if we do any
5948 change. */
5949 static bool
5950 undo_optional_reloads (void)
5952 bool change_p, keep_p;
5953 unsigned int regno, uid;
5954 bitmap_iterator bi, bi2;
5955 rtx_insn *insn;
5956 rtx set, src, dest;
5957 bitmap_head removed_optional_reload_pseudos, insn_bitmap;
5959 bitmap_initialize (&removed_optional_reload_pseudos, &reg_obstack);
5960 bitmap_copy (&removed_optional_reload_pseudos, &lra_optional_reload_pseudos);
5961 EXECUTE_IF_SET_IN_BITMAP (&lra_optional_reload_pseudos, 0, regno, bi)
5963 keep_p = false;
5964 /* Keep optional reloads from previous subpasses. */
5965 if (lra_reg_info[regno].restore_regno < 0
5966 /* If the original pseudo changed its allocation, just
5967 removing the optional pseudo is dangerous as the original
5968 pseudo will have longer live range. */
5969 || reg_renumber[lra_reg_info[regno].restore_regno] >= 0)
5970 keep_p = true;
5971 else if (reg_renumber[regno] >= 0)
5972 EXECUTE_IF_SET_IN_BITMAP (&lra_reg_info[regno].insn_bitmap, 0, uid, bi2)
5974 insn = lra_insn_recog_data[uid]->insn;
5975 if ((set = single_set (insn)) == NULL_RTX)
5976 continue;
5977 src = SET_SRC (set);
5978 dest = SET_DEST (set);
5979 if (! REG_P (src) || ! REG_P (dest))
5980 continue;
5981 if (REGNO (dest) == regno
5982 /* Ignore insn for optional reloads itself. */
5983 && lra_reg_info[regno].restore_regno != (int) REGNO (src)
5984 /* Check only inheritance on last inheritance pass. */
5985 && (int) REGNO (src) >= new_regno_start
5986 /* Check that the optional reload was inherited. */
5987 && bitmap_bit_p (&lra_inheritance_pseudos, REGNO (src)))
5989 keep_p = true;
5990 break;
5993 if (keep_p)
5995 bitmap_clear_bit (&removed_optional_reload_pseudos, regno);
5996 if (lra_dump_file != NULL)
5997 fprintf (lra_dump_file, "Keep optional reload reg %d\n", regno);
6000 change_p = ! bitmap_empty_p (&removed_optional_reload_pseudos);
6001 bitmap_initialize (&insn_bitmap, &reg_obstack);
6002 EXECUTE_IF_SET_IN_BITMAP (&removed_optional_reload_pseudos, 0, regno, bi)
6004 if (lra_dump_file != NULL)
6005 fprintf (lra_dump_file, "Remove optional reload reg %d\n", regno);
6006 bitmap_copy (&insn_bitmap, &lra_reg_info[regno].insn_bitmap);
6007 EXECUTE_IF_SET_IN_BITMAP (&insn_bitmap, 0, uid, bi2)
6009 insn = lra_insn_recog_data[uid]->insn;
6010 if ((set = single_set (insn)) != NULL_RTX)
6012 src = SET_SRC (set);
6013 dest = SET_DEST (set);
6014 if (REG_P (src) && REG_P (dest)
6015 && ((REGNO (src) == regno
6016 && (lra_reg_info[regno].restore_regno
6017 == (int) REGNO (dest)))
6018 || (REGNO (dest) == regno
6019 && (lra_reg_info[regno].restore_regno
6020 == (int) REGNO (src)))))
6022 if (lra_dump_file != NULL)
6024 fprintf (lra_dump_file, " Deleting move %u\n",
6025 INSN_UID (insn));
6026 dump_insn_slim (lra_dump_file, insn);
6028 lra_set_insn_deleted (insn);
6029 continue;
6031 /* We should not worry about generation memory-memory
6032 moves here as if the corresponding inheritance did
6033 not work (inheritance pseudo did not get a hard reg),
6034 we remove the inheritance pseudo and the optional
6035 reload. */
6037 lra_substitute_pseudo_within_insn (
6038 insn, regno,
6039 regno_reg_rtx[lra_reg_info[regno].restore_regno]);
6040 lra_update_insn_regno_info (insn);
6041 if (lra_dump_file != NULL)
6043 fprintf (lra_dump_file,
6044 " Restoring original insn:\n");
6045 dump_insn_slim (lra_dump_file, insn);
6049 /* Clear restore_regnos. */
6050 EXECUTE_IF_SET_IN_BITMAP (&lra_optional_reload_pseudos, 0, regno, bi)
6051 lra_reg_info[regno].restore_regno = -1;
6052 bitmap_clear (&insn_bitmap);
6053 bitmap_clear (&removed_optional_reload_pseudos);
6054 return change_p;
6057 /* Entry function for undoing inheritance/split transformation. Return true
6058 if we did any RTL change in this pass. */
6059 bool
6060 lra_undo_inheritance (void)
6062 unsigned int regno;
6063 int restore_regno, hard_regno;
6064 int n_all_inherit, n_inherit, n_all_split, n_split;
6065 bitmap_head remove_pseudos;
6066 bitmap_iterator bi;
6067 bool change_p;
6069 lra_undo_inheritance_iter++;
6070 if (lra_undo_inheritance_iter > LRA_MAX_INHERITANCE_PASSES)
6071 return false;
6072 if (lra_dump_file != NULL)
6073 fprintf (lra_dump_file,
6074 "\n********** Undoing inheritance #%d: **********\n\n",
6075 lra_undo_inheritance_iter);
6076 bitmap_initialize (&remove_pseudos, &reg_obstack);
6077 n_inherit = n_all_inherit = 0;
6078 EXECUTE_IF_SET_IN_BITMAP (&lra_inheritance_pseudos, 0, regno, bi)
6079 if (lra_reg_info[regno].restore_regno >= 0)
6081 n_all_inherit++;
6082 if (reg_renumber[regno] < 0
6083 /* If the original pseudo changed its allocation, just
6084 removing inheritance is dangerous as for changing
6085 allocation we used shorter live-ranges. */
6086 && reg_renumber[lra_reg_info[regno].restore_regno] < 0)
6087 bitmap_set_bit (&remove_pseudos, regno);
6088 else
6089 n_inherit++;
6091 if (lra_dump_file != NULL && n_all_inherit != 0)
6092 fprintf (lra_dump_file, "Inherit %d out of %d (%.2f%%)\n",
6093 n_inherit, n_all_inherit,
6094 (double) n_inherit / n_all_inherit * 100);
6095 n_split = n_all_split = 0;
6096 EXECUTE_IF_SET_IN_BITMAP (&lra_split_regs, 0, regno, bi)
6097 if ((restore_regno = lra_reg_info[regno].restore_regno) >= 0)
6099 n_all_split++;
6100 hard_regno = (restore_regno >= FIRST_PSEUDO_REGISTER
6101 ? reg_renumber[restore_regno] : restore_regno);
6102 if (hard_regno < 0 || reg_renumber[regno] == hard_regno)
6103 bitmap_set_bit (&remove_pseudos, regno);
6104 else
6106 n_split++;
6107 if (lra_dump_file != NULL)
6108 fprintf (lra_dump_file, " Keep split r%d (orig=r%d)\n",
6109 regno, restore_regno);
6112 if (lra_dump_file != NULL && n_all_split != 0)
6113 fprintf (lra_dump_file, "Split %d out of %d (%.2f%%)\n",
6114 n_split, n_all_split,
6115 (double) n_split / n_all_split * 100);
6116 change_p = remove_inheritance_pseudos (&remove_pseudos);
6117 bitmap_clear (&remove_pseudos);
6118 /* Clear restore_regnos. */
6119 EXECUTE_IF_SET_IN_BITMAP (&lra_inheritance_pseudos, 0, regno, bi)
6120 lra_reg_info[regno].restore_regno = -1;
6121 EXECUTE_IF_SET_IN_BITMAP (&lra_split_regs, 0, regno, bi)
6122 lra_reg_info[regno].restore_regno = -1;
6123 change_p = undo_optional_reloads () || change_p;
6124 return change_p;