1 /* Search an insn for pseudo regs that must be in hard regs and are not.
2 Copyright (C) 1987, 88, 89, 92, 93, 94, 1995 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
22 /* This file contains subroutines used only from the file reload1.c.
23 It knows how to scan one insn for operands and values
24 that need to be copied into registers to make valid code.
25 It also finds other operands and values which are valid
26 but for which equivalent values in registers exist and
27 ought to be used instead.
29 Before processing the first insn of the function, call `init_reload'.
31 To scan an insn, call `find_reloads'. This does two things:
32 1. sets up tables describing which values must be reloaded
33 for this insn, and what kind of hard regs they must be reloaded into;
34 2. optionally record the locations where those values appear in
35 the data, so they can be replaced properly later.
36 This is done only if the second arg to `find_reloads' is nonzero.
38 The third arg to `find_reloads' specifies the number of levels
39 of indirect addressing supported by the machine. If it is zero,
40 indirect addressing is not valid. If it is one, (MEM (REG n))
41 is valid even if (REG n) did not get a hard register; if it is two,
42 (MEM (MEM (REG n))) is also valid even if (REG n) did not get a
43 hard register, and similarly for higher values.
45 Then you must choose the hard regs to reload those pseudo regs into,
46 and generate appropriate load insns before this insn and perhaps
47 also store insns after this insn. Set up the array `reload_reg_rtx'
48 to contain the REG rtx's for the registers you used. In some
49 cases `find_reloads' will return a nonzero value in `reload_reg_rtx'
50 for certain reloads. Then that tells you which register to use,
51 so you do not need to allocate one. But you still do need to add extra
52 instructions to copy the value into and out of that register.
54 Finally you must call `subst_reloads' to substitute the reload reg rtx's
55 into the locations already recorded.
59 find_reloads can alter the operands of the instruction it is called on.
61 1. Two operands of any sort may be interchanged, if they are in a
62 commutative instruction.
63 This happens only if find_reloads thinks the instruction will compile
66 2. Pseudo-registers that are equivalent to constants are replaced
67 with those constants if they are not in hard registers.
69 1 happens every time find_reloads is called.
70 2 happens only when REPLACE is 1, which is only when
71 actually doing the reloads, not when just counting them.
74 Using a reload register for several reloads in one insn:
76 When an insn has reloads, it is considered as having three parts:
77 the input reloads, the insn itself after reloading, and the output reloads.
78 Reloads of values used in memory addresses are often needed for only one part.
80 When this is so, reload_when_needed records which part needs the reload.
81 Two reloads for different parts of the insn can share the same reload
84 When a reload is used for addresses in multiple parts, or when it is
85 an ordinary operand, it is classified as RELOAD_OTHER, and cannot share
86 a register with any other reload. */
93 #include "insn-config.h"
94 #include "insn-codes.h"
98 #include "hard-reg-set.h"
103 #ifndef REGISTER_MOVE_COST
104 #define REGISTER_MOVE_COST(x, y) 2
107 /* The variables set up by `find_reloads' are:
109 n_reloads number of distinct reloads needed; max reload # + 1
110 tables indexed by reload number
111 reload_in rtx for value to reload from
112 reload_out rtx for where to store reload-reg afterward if nec
113 (often the same as reload_in)
114 reload_reg_class enum reg_class, saying what regs to reload into
115 reload_inmode enum machine_mode; mode this operand should have
116 when reloaded, on input.
117 reload_outmode enum machine_mode; mode this operand should have
118 when reloaded, on output.
119 reload_optional char, nonzero for an optional reload.
120 Optional reloads are ignored unless the
121 value is already sitting in a register.
122 reload_inc int, positive amount to increment or decrement by if
123 reload_in is a PRE_DEC, PRE_INC, POST_DEC, POST_INC.
124 Ignored otherwise (don't assume it is zero).
125 reload_in_reg rtx. A reg for which reload_in is the equivalent.
126 If reload_in is a symbol_ref which came from
127 reg_equiv_constant, then this is the pseudo
128 which has that symbol_ref as equivalent.
129 reload_reg_rtx rtx. This is the register to reload into.
130 If it is zero when `find_reloads' returns,
131 you must find a suitable register in the class
132 specified by reload_reg_class, and store here
133 an rtx for that register with mode from
134 reload_inmode or reload_outmode.
135 reload_nocombine char, nonzero if this reload shouldn't be
136 combined with another reload.
137 reload_opnum int, operand number being reloaded. This is
138 used to group related reloads and need not always
139 be equal to the actual operand number in the insn,
140 though it current will be; for in-out operands, it
141 is one of the two operand numbers.
142 reload_when_needed enum, classifies reload as needed either for
143 addressing an input reload, addressing an output,
144 for addressing a non-reloaded mem ref,
145 or for unspecified purposes (i.e., more than one
147 reload_secondary_p int, 1 if this is a secondary register for one
149 reload_secondary_in_reload
150 reload_secondary_out_reload
151 int, gives the reload number of a secondary
152 reload, when needed; otherwise -1
153 reload_secondary_in_icode
154 reload_secondary_out_icode
155 enum insn_code, if a secondary reload is required,
156 gives the INSN_CODE that uses the secondary
157 reload as a scratch register, or CODE_FOR_nothing
158 if the secondary reload register is to be an
159 intermediate register. */
162 rtx reload_in[MAX_RELOADS];
163 rtx reload_out[MAX_RELOADS];
164 enum reg_class reload_reg_class[MAX_RELOADS];
165 enum machine_mode reload_inmode[MAX_RELOADS];
166 enum machine_mode reload_outmode[MAX_RELOADS];
167 rtx reload_reg_rtx[MAX_RELOADS];
168 char reload_optional[MAX_RELOADS];
169 int reload_inc[MAX_RELOADS];
170 rtx reload_in_reg[MAX_RELOADS];
171 char reload_nocombine[MAX_RELOADS];
172 int reload_opnum[MAX_RELOADS];
173 enum reload_type reload_when_needed[MAX_RELOADS];
174 int reload_secondary_p[MAX_RELOADS];
175 int reload_secondary_in_reload[MAX_RELOADS];
176 int reload_secondary_out_reload[MAX_RELOADS];
177 enum insn_code reload_secondary_in_icode[MAX_RELOADS];
178 enum insn_code reload_secondary_out_icode[MAX_RELOADS];
180 /* All the "earlyclobber" operands of the current insn
181 are recorded here. */
183 rtx reload_earlyclobbers[MAX_RECOG_OPERANDS];
185 int reload_n_operands;
187 /* Replacing reloads.
189 If `replace_reloads' is nonzero, then as each reload is recorded
190 an entry is made for it in the table `replacements'.
191 Then later `subst_reloads' can look through that table and
192 perform all the replacements needed. */
194 /* Nonzero means record the places to replace. */
195 static int replace_reloads;
197 /* Each replacement is recorded with a structure like this. */
200 rtx *where; /* Location to store in */
201 rtx *subreg_loc; /* Location of SUBREG if WHERE is inside
202 a SUBREG; 0 otherwise. */
203 int what; /* which reload this is for */
204 enum machine_mode mode; /* mode it must have */
207 static struct replacement replacements[MAX_RECOG_OPERANDS * ((MAX_REGS_PER_ADDRESS * 2) + 1)];
209 /* Number of replacements currently recorded. */
210 static int n_replacements;
212 /* Used to track what is modified by an operand. */
215 int reg_flag; /* Nonzero if referencing a register. */
216 int safe; /* Nonzero if this can't conflict with anything. */
217 rtx base; /* Base address for MEM. */
218 HOST_WIDE_INT start; /* Starting offset or register number. */
219 HOST_WIDE_INT end; /* Ending offset or register number. */
222 /* MEM-rtx's created for pseudo-regs in stack slots not directly addressable;
223 (see reg_equiv_address). */
224 static rtx memlocs[MAX_RECOG_OPERANDS * ((MAX_REGS_PER_ADDRESS * 2) + 1)];
225 static int n_memlocs;
227 #ifdef SECONDARY_MEMORY_NEEDED
229 /* Save MEMs needed to copy from one class of registers to another. One MEM
230 is used per mode, but normally only one or two modes are ever used.
232 We keep two versions, before and after register elimination. The one
233 after register elimination is record separately for each operand. This
234 is done in case the address is not valid to be sure that we separately
237 static rtx secondary_memlocs[NUM_MACHINE_MODES];
238 static rtx secondary_memlocs_elim[NUM_MACHINE_MODES][MAX_RECOG_OPERANDS];
241 /* The instruction we are doing reloads for;
242 so we can test whether a register dies in it. */
243 static rtx this_insn;
245 /* Nonzero if this instruction is a user-specified asm with operands. */
246 static int this_insn_is_asm;
248 /* If hard_regs_live_known is nonzero,
249 we can tell which hard regs are currently live,
250 at least enough to succeed in choosing dummy reloads. */
251 static int hard_regs_live_known;
253 /* Indexed by hard reg number,
254 element is nonegative if hard reg has been spilled.
255 This vector is passed to `find_reloads' as an argument
256 and is not changed here. */
257 static short *static_reload_reg_p;
259 /* Set to 1 in subst_reg_equivs if it changes anything. */
260 static int subst_reg_equivs_changed;
262 /* On return from push_reload, holds the reload-number for the OUT
263 operand, which can be different for that from the input operand. */
264 static int output_reloadnum;
266 /* Compare two RTX's. */
267 #define MATCHES(x, y) \
268 (x == y || (x != 0 && (GET_CODE (x) == REG \
269 ? GET_CODE (y) == REG && REGNO (x) == REGNO (y) \
270 : rtx_equal_p (x, y) && ! side_effects_p (x))))
272 /* Indicates if two reloads purposes are for similar enough things that we
273 can merge their reloads. */
274 #define MERGABLE_RELOADS(when1, when2, op1, op2) \
275 ((when1) == RELOAD_OTHER || (when2) == RELOAD_OTHER \
276 || ((when1) == (when2) && (op1) == (op2)) \
277 || ((when1) == RELOAD_FOR_INPUT && (when2) == RELOAD_FOR_INPUT) \
278 || ((when1) == RELOAD_FOR_OPERAND_ADDRESS \
279 && (when2) == RELOAD_FOR_OPERAND_ADDRESS) \
280 || ((when1) == RELOAD_FOR_OTHER_ADDRESS \
281 && (when2) == RELOAD_FOR_OTHER_ADDRESS))
283 /* Nonzero if these two reload purposes produce RELOAD_OTHER when merged. */
284 #define MERGE_TO_OTHER(when1, when2, op1, op2) \
285 ((when1) != (when2) \
286 || ! ((op1) == (op2) \
287 || (when1) == RELOAD_FOR_INPUT \
288 || (when1) == RELOAD_FOR_OPERAND_ADDRESS \
289 || (when1) == RELOAD_FOR_OTHER_ADDRESS))
291 static int push_secondary_reload PROTO((int, rtx, int, int, enum reg_class,
292 enum machine_mode, enum reload_type,
294 static int push_reload PROTO((rtx, rtx, rtx *, rtx *, enum reg_class,
295 enum machine_mode, enum machine_mode,
296 int, int, int, enum reload_type));
297 static void push_replacement PROTO((rtx *, int, enum machine_mode));
298 static void combine_reloads PROTO((void));
299 static rtx find_dummy_reload PROTO((rtx, rtx, rtx *, rtx *,
300 enum machine_mode, enum machine_mode,
301 enum reg_class, int));
302 static int earlyclobber_operand_p PROTO((rtx));
303 static int hard_reg_set_here_p PROTO((int, int, rtx));
304 static struct decomposition decompose PROTO((rtx));
305 static int immune_p PROTO((rtx, rtx, struct decomposition));
306 static int alternative_allows_memconst PROTO((char *, int));
307 static rtx find_reloads_toplev PROTO((rtx, int, enum reload_type, int, int));
308 static rtx make_memloc PROTO((rtx, int));
309 static int find_reloads_address PROTO((enum machine_mode, rtx *, rtx, rtx *,
310 int, enum reload_type, int));
311 static rtx subst_reg_equivs PROTO((rtx));
312 static rtx subst_indexed_address PROTO((rtx));
313 static int find_reloads_address_1 PROTO((rtx, int, rtx *, int,
314 enum reload_type,int));
315 static void find_reloads_address_part PROTO((rtx, rtx *, enum reg_class,
316 enum machine_mode, int,
317 enum reload_type, int));
318 static int find_inc_amount PROTO((rtx, rtx));
320 #ifdef HAVE_SECONDARY_RELOADS
322 /* Determine if any secondary reloads are needed for loading (if IN_P is
323 non-zero) or storing (if IN_P is zero) X to or from a reload register of
324 register class RELOAD_CLASS in mode RELOAD_MODE. If secondary reloads
325 are needed, push them.
327 Return the reload number of the secondary reload we made, or -1 if
328 we didn't need one. *PICODE is set to the insn_code to use if we do
329 need a secondary reload. */
332 push_secondary_reload (in_p, x, opnum, optional, reload_class, reload_mode,
338 enum reg_class reload_class;
339 enum machine_mode reload_mode;
340 enum reload_type type;
341 enum insn_code *picode;
343 enum reg_class class = NO_REGS;
344 enum machine_mode mode = reload_mode;
345 enum insn_code icode = CODE_FOR_nothing;
346 enum reg_class t_class = NO_REGS;
347 enum machine_mode t_mode = VOIDmode;
348 enum insn_code t_icode = CODE_FOR_nothing;
349 enum reload_type secondary_type;
351 int s_reload, t_reload = -1;
353 if (type == RELOAD_FOR_INPUT_ADDRESS || type == RELOAD_FOR_OUTPUT_ADDRESS)
354 secondary_type = type;
356 secondary_type = in_p ? RELOAD_FOR_INPUT_ADDRESS : RELOAD_FOR_OUTPUT_ADDRESS;
358 *picode = CODE_FOR_nothing;
360 /* If X is a paradoxical SUBREG, use the inner value to determine both the
361 mode and object being reloaded. */
362 if (GET_CODE (x) == SUBREG
363 && (GET_MODE_SIZE (GET_MODE (x))
364 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))))
367 reload_mode = GET_MODE (x);
370 /* If X is a pseudo-register that has an equivalent MEM (actually, if it
371 is still a pseudo-register by now, it *must* have an equivalent MEM
372 but we don't want to assume that), use that equivalent when seeing if
373 a secondary reload is needed since whether or not a reload is needed
374 might be sensitive to the form of the MEM. */
376 if (GET_CODE (x) == REG && REGNO (x) >= FIRST_PSEUDO_REGISTER
377 && reg_equiv_mem[REGNO (x)] != 0)
378 x = reg_equiv_mem[REGNO (x)];
380 #ifdef SECONDARY_INPUT_RELOAD_CLASS
382 class = SECONDARY_INPUT_RELOAD_CLASS (reload_class, reload_mode, x);
385 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
387 class = SECONDARY_OUTPUT_RELOAD_CLASS (reload_class, reload_mode, x);
390 /* If we don't need any secondary registers, done. */
391 if (class == NO_REGS)
394 /* Get a possible insn to use. If the predicate doesn't accept X, don't
397 icode = (in_p ? reload_in_optab[(int) reload_mode]
398 : reload_out_optab[(int) reload_mode]);
400 if (icode != CODE_FOR_nothing
401 && insn_operand_predicate[(int) icode][in_p]
402 && (! (insn_operand_predicate[(int) icode][in_p]) (x, reload_mode)))
403 icode = CODE_FOR_nothing;
405 /* If we will be using an insn, see if it can directly handle the reload
406 register we will be using. If it can, the secondary reload is for a
407 scratch register. If it can't, we will use the secondary reload for
408 an intermediate register and require a tertiary reload for the scratch
411 if (icode != CODE_FOR_nothing)
413 /* If IN_P is non-zero, the reload register will be the output in
414 operand 0. If IN_P is zero, the reload register will be the input
415 in operand 1. Outputs should have an initial "=", which we must
418 char insn_letter = insn_operand_constraint[(int) icode][!in_p][in_p];
419 enum reg_class insn_class
420 = (insn_letter == 'r' ? GENERAL_REGS
421 : REG_CLASS_FROM_LETTER (insn_letter));
423 if (insn_class == NO_REGS
424 || (in_p && insn_operand_constraint[(int) icode][!in_p][0] != '=')
425 /* The scratch register's constraint must start with "=&". */
426 || insn_operand_constraint[(int) icode][2][0] != '='
427 || insn_operand_constraint[(int) icode][2][1] != '&')
430 if (reg_class_subset_p (reload_class, insn_class))
431 mode = insn_operand_mode[(int) icode][2];
434 char t_letter = insn_operand_constraint[(int) icode][2][2];
436 t_mode = insn_operand_mode[(int) icode][2];
437 t_class = (t_letter == 'r' ? GENERAL_REGS
438 : REG_CLASS_FROM_LETTER (t_letter));
440 icode = CODE_FOR_nothing;
444 /* This case isn't valid, so fail. Reload is allowed to use the same
445 register for RELOAD_FOR_INPUT_ADDRESS and RELOAD_FOR_INPUT reloads, but
446 in the case of a secondary register, we actually need two different
447 registers for correct code. We fail here to prevent the possibility of
448 silently generating incorrect code later.
450 The convention is that secondary input reloads are valid only if the
451 secondary_class is different from class. If you have such a case, you
452 can not use secondary reloads, you must work around the problem some
455 Allow this when MODE is not reload_mode and assume that the generated
456 code handles this case (it does on the Alpha, which is the only place
457 this currently happens). */
459 if (in_p && class == reload_class && mode == reload_mode)
462 /* If we need a tertiary reload, see if we have one we can reuse or else
465 if (t_class != NO_REGS)
467 for (t_reload = 0; t_reload < n_reloads; t_reload++)
468 if (reload_secondary_p[t_reload]
469 && (reg_class_subset_p (t_class, reload_reg_class[t_reload])
470 || reg_class_subset_p (reload_reg_class[t_reload], t_class))
471 && ((in_p && reload_inmode[t_reload] == t_mode)
472 || (! in_p && reload_outmode[t_reload] == t_mode))
473 && ((in_p && (reload_secondary_in_icode[t_reload]
474 == CODE_FOR_nothing))
475 || (! in_p &&(reload_secondary_out_icode[t_reload]
476 == CODE_FOR_nothing)))
477 && (reg_class_size[(int) t_class] == 1
478 #ifdef SMALL_REGISTER_CLASSES
482 && MERGABLE_RELOADS (secondary_type,
483 reload_when_needed[t_reload],
484 opnum, reload_opnum[t_reload]))
487 reload_inmode[t_reload] = t_mode;
489 reload_outmode[t_reload] = t_mode;
491 if (reg_class_subset_p (t_class, reload_reg_class[t_reload]))
492 reload_reg_class[t_reload] = t_class;
494 reload_opnum[t_reload] = MIN (reload_opnum[t_reload], opnum);
495 reload_optional[t_reload] &= optional;
496 reload_secondary_p[t_reload] = 1;
497 if (MERGE_TO_OTHER (secondary_type, reload_when_needed[t_reload],
498 opnum, reload_opnum[t_reload]))
499 reload_when_needed[t_reload] = RELOAD_OTHER;
502 if (t_reload == n_reloads)
504 /* We need to make a new tertiary reload for this register class. */
505 reload_in[t_reload] = reload_out[t_reload] = 0;
506 reload_reg_class[t_reload] = t_class;
507 reload_inmode[t_reload] = in_p ? t_mode : VOIDmode;
508 reload_outmode[t_reload] = ! in_p ? t_mode : VOIDmode;
509 reload_reg_rtx[t_reload] = 0;
510 reload_optional[t_reload] = optional;
511 reload_inc[t_reload] = 0;
512 /* Maybe we could combine these, but it seems too tricky. */
513 reload_nocombine[t_reload] = 1;
514 reload_in_reg[t_reload] = 0;
515 reload_opnum[t_reload] = opnum;
516 reload_when_needed[t_reload] = secondary_type;
517 reload_secondary_in_reload[t_reload] = -1;
518 reload_secondary_out_reload[t_reload] = -1;
519 reload_secondary_in_icode[t_reload] = CODE_FOR_nothing;
520 reload_secondary_out_icode[t_reload] = CODE_FOR_nothing;
521 reload_secondary_p[t_reload] = 1;
527 /* See if we can reuse an existing secondary reload. */
528 for (s_reload = 0; s_reload < n_reloads; s_reload++)
529 if (reload_secondary_p[s_reload]
530 && (reg_class_subset_p (class, reload_reg_class[s_reload])
531 || reg_class_subset_p (reload_reg_class[s_reload], class))
532 && ((in_p && reload_inmode[s_reload] == mode)
533 || (! in_p && reload_outmode[s_reload] == mode))
534 && ((in_p && reload_secondary_in_reload[s_reload] == t_reload)
535 || (! in_p && reload_secondary_out_reload[s_reload] == t_reload))
536 && ((in_p && reload_secondary_in_icode[s_reload] == t_icode)
537 || (! in_p && reload_secondary_out_icode[s_reload] == t_icode))
538 && (reg_class_size[(int) class] == 1
539 #ifdef SMALL_REGISTER_CLASSES
543 && MERGABLE_RELOADS (secondary_type, reload_when_needed[s_reload],
544 opnum, reload_opnum[s_reload]))
547 reload_inmode[s_reload] = mode;
549 reload_outmode[s_reload] = mode;
551 if (reg_class_subset_p (class, reload_reg_class[s_reload]))
552 reload_reg_class[s_reload] = class;
554 reload_opnum[s_reload] = MIN (reload_opnum[s_reload], opnum);
555 reload_optional[s_reload] &= optional;
556 reload_secondary_p[s_reload] = 1;
557 if (MERGE_TO_OTHER (secondary_type, reload_when_needed[s_reload],
558 opnum, reload_opnum[s_reload]))
559 reload_when_needed[s_reload] = RELOAD_OTHER;
562 if (s_reload == n_reloads)
564 /* We need to make a new secondary reload for this register class. */
565 reload_in[s_reload] = reload_out[s_reload] = 0;
566 reload_reg_class[s_reload] = class;
568 reload_inmode[s_reload] = in_p ? mode : VOIDmode;
569 reload_outmode[s_reload] = ! in_p ? mode : VOIDmode;
570 reload_reg_rtx[s_reload] = 0;
571 reload_optional[s_reload] = optional;
572 reload_inc[s_reload] = 0;
573 /* Maybe we could combine these, but it seems too tricky. */
574 reload_nocombine[s_reload] = 1;
575 reload_in_reg[s_reload] = 0;
576 reload_opnum[s_reload] = opnum;
577 reload_when_needed[s_reload] = secondary_type;
578 reload_secondary_in_reload[s_reload] = in_p ? t_reload : -1;
579 reload_secondary_out_reload[s_reload] = ! in_p ? t_reload : -1;
580 reload_secondary_in_icode[s_reload] = in_p ? t_icode : CODE_FOR_nothing;
581 reload_secondary_out_icode[s_reload]
582 = ! in_p ? t_icode : CODE_FOR_nothing;
583 reload_secondary_p[s_reload] = 1;
587 #ifdef SECONDARY_MEMORY_NEEDED
588 /* If we need a memory location to copy between the two reload regs,
591 if (in_p && icode == CODE_FOR_nothing
592 && SECONDARY_MEMORY_NEEDED (class, reload_class, reload_mode))
593 get_secondary_mem (x, reload_mode, opnum, type);
595 if (! in_p && icode == CODE_FOR_nothing
596 && SECONDARY_MEMORY_NEEDED (reload_class, class, reload_mode))
597 get_secondary_mem (x, reload_mode, opnum, type);
604 #endif /* HAVE_SECONDARY_RELOADS */
606 #ifdef SECONDARY_MEMORY_NEEDED
608 /* Return a memory location that will be used to copy X in mode MODE.
609 If we haven't already made a location for this mode in this insn,
610 call find_reloads_address on the location being returned. */
613 get_secondary_mem (x, mode, opnum, type)
615 enum machine_mode mode;
617 enum reload_type type;
622 /* By default, if MODE is narrower than a word, widen it to a word.
623 This is required because most machines that require these memory
624 locations do not support short load and stores from all registers
625 (e.g., FP registers). */
627 #ifdef SECONDARY_MEMORY_NEEDED_MODE
628 mode = SECONDARY_MEMORY_NEEDED_MODE (mode);
630 if (GET_MODE_BITSIZE (mode) < BITS_PER_WORD)
631 mode = mode_for_size (BITS_PER_WORD, GET_MODE_CLASS (mode), 0);
634 /* If we already have made a MEM for this operand in MODE, return it. */
635 if (secondary_memlocs_elim[(int) mode][opnum] != 0)
636 return secondary_memlocs_elim[(int) mode][opnum];
638 /* If this is the first time we've tried to get a MEM for this mode,
639 allocate a new one. `something_changed' in reload will get set
640 by noticing that the frame size has changed. */
642 if (secondary_memlocs[(int) mode] == 0)
644 #ifdef SECONDARY_MEMORY_NEEDED_RTX
645 secondary_memlocs[(int) mode] = SECONDARY_MEMORY_NEEDED_RTX (mode);
647 secondary_memlocs[(int) mode]
648 = assign_stack_local (mode, GET_MODE_SIZE (mode), 0);
652 /* Get a version of the address doing any eliminations needed. If that
653 didn't give us a new MEM, make a new one if it isn't valid. */
655 loc = eliminate_regs (secondary_memlocs[(int) mode], VOIDmode, NULL_RTX);
656 mem_valid = strict_memory_address_p (mode, XEXP (loc, 0));
658 if (! mem_valid && loc == secondary_memlocs[(int) mode])
659 loc = copy_rtx (loc);
661 /* The only time the call below will do anything is if the stack
662 offset is too large. In that case IND_LEVELS doesn't matter, so we
663 can just pass a zero. Adjust the type to be the address of the
664 corresponding object. If the address was valid, save the eliminated
665 address. If it wasn't valid, we need to make a reload each time, so
670 type = (type == RELOAD_FOR_INPUT ? RELOAD_FOR_INPUT_ADDRESS
671 : type == RELOAD_FOR_OUTPUT ? RELOAD_FOR_OUTPUT_ADDRESS
674 find_reloads_address (mode, NULL_PTR, XEXP (loc, 0), &XEXP (loc, 0),
678 secondary_memlocs_elim[(int) mode][opnum] = loc;
682 /* Clear any secondary memory locations we've made. */
685 clear_secondary_mem ()
687 bzero ((char *) secondary_memlocs, sizeof secondary_memlocs);
689 #endif /* SECONDARY_MEMORY_NEEDED */
691 /* Record one reload that needs to be performed.
692 IN is an rtx saying where the data are to be found before this instruction.
693 OUT says where they must be stored after the instruction.
694 (IN is zero for data not read, and OUT is zero for data not written.)
695 INLOC and OUTLOC point to the places in the instructions where
696 IN and OUT were found.
697 If IN and OUT are both non-zero, it means the same register must be used
698 to reload both IN and OUT.
700 CLASS is a register class required for the reloaded data.
701 INMODE is the machine mode that the instruction requires
702 for the reg that replaces IN and OUTMODE is likewise for OUT.
704 If IN is zero, then OUT's location and mode should be passed as
707 STRICT_LOW is the 1 if there is a containing STRICT_LOW_PART rtx.
709 OPTIONAL nonzero means this reload does not need to be performed:
710 it can be discarded if that is more convenient.
712 OPNUM and TYPE say what the purpose of this reload is.
714 The return value is the reload-number for this reload.
716 If both IN and OUT are nonzero, in some rare cases we might
717 want to make two separate reloads. (Actually we never do this now.)
718 Therefore, the reload-number for OUT is stored in
719 output_reloadnum when we return; the return value applies to IN.
720 Usually (presently always), when IN and OUT are nonzero,
721 the two reload-numbers are equal, but the caller should be careful to
725 push_reload (in, out, inloc, outloc, class,
726 inmode, outmode, strict_low, optional, opnum, type)
727 register rtx in, out;
729 enum reg_class class;
730 enum machine_mode inmode, outmode;
734 enum reload_type type;
738 int dont_remove_subreg = 0;
739 rtx *in_subreg_loc = 0, *out_subreg_loc = 0;
740 int secondary_in_reload = -1, secondary_out_reload = -1;
741 enum insn_code secondary_in_icode = CODE_FOR_nothing;
742 enum insn_code secondary_out_icode = CODE_FOR_nothing;
744 /* INMODE and/or OUTMODE could be VOIDmode if no mode
745 has been specified for the operand. In that case,
746 use the operand's mode as the mode to reload. */
747 if (inmode == VOIDmode && in != 0)
748 inmode = GET_MODE (in);
749 if (outmode == VOIDmode && out != 0)
750 outmode = GET_MODE (out);
752 /* If IN is a pseudo register everywhere-equivalent to a constant, and
753 it is not in a hard register, reload straight from the constant,
754 since we want to get rid of such pseudo registers.
755 Often this is done earlier, but not always in find_reloads_address. */
756 if (in != 0 && GET_CODE (in) == REG)
758 register int regno = REGNO (in);
760 if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0
761 && reg_equiv_constant[regno] != 0)
762 in = reg_equiv_constant[regno];
765 /* Likewise for OUT. Of course, OUT will never be equivalent to
766 an actual constant, but it might be equivalent to a memory location
767 (in the case of a parameter). */
768 if (out != 0 && GET_CODE (out) == REG)
770 register int regno = REGNO (out);
772 if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0
773 && reg_equiv_constant[regno] != 0)
774 out = reg_equiv_constant[regno];
777 /* If we have a read-write operand with an address side-effect,
778 change either IN or OUT so the side-effect happens only once. */
779 if (in != 0 && out != 0 && GET_CODE (in) == MEM && rtx_equal_p (in, out))
781 if (GET_CODE (XEXP (in, 0)) == POST_INC
782 || GET_CODE (XEXP (in, 0)) == POST_DEC)
783 in = gen_rtx (MEM, GET_MODE (in), XEXP (XEXP (in, 0), 0));
784 if (GET_CODE (XEXP (in, 0)) == PRE_INC
785 || GET_CODE (XEXP (in, 0)) == PRE_DEC)
786 out = gen_rtx (MEM, GET_MODE (out), XEXP (XEXP (out, 0), 0));
789 /* If we are reloading a (SUBREG constant ...), really reload just the
790 inside expression in its own mode. Similarly for (SUBREG (PLUS ...)).
791 If we have (SUBREG:M1 (MEM:M2 ...) ...) (or an inner REG that is still
792 a pseudo and hence will become a MEM) with M1 wider than M2 and the
793 register is a pseudo, also reload the inside expression.
794 For machines that extend byte loads, do this for any SUBREG of a pseudo
795 where both M1 and M2 are a word or smaller, M1 is wider than M2, and
796 M2 is an integral mode that gets extended when loaded.
797 Similar issue for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where
798 either M1 is not valid for R or M2 is wider than a word but we only
799 need one word to store an M2-sized quantity in R.
800 (However, if OUT is nonzero, we need to reload the reg *and*
801 the subreg, so do nothing here, and let following statement handle it.)
803 Note that the case of (SUBREG (CONST_INT...)...) is handled elsewhere;
804 we can't handle it here because CONST_INT does not indicate a mode.
806 Similarly, we must reload the inside expression if we have a
807 STRICT_LOW_PART (presumably, in == out in the cas).
809 Also reload the inner expression if it does not require a secondary
810 reload but the SUBREG does.
812 Finally, reload the inner expression if it is a register that is in
813 the class whose registers cannot be referenced in a different size
814 and M1 is not the same size as M2. If SUBREG_WORD is nonzero, we
815 cannot reload just the inside since we might end up with the wrong
818 if (in != 0 && GET_CODE (in) == SUBREG && SUBREG_WORD (in) == 0
819 #ifdef CLASS_CANNOT_CHANGE_SIZE
820 && class != CLASS_CANNOT_CHANGE_SIZE
822 && (CONSTANT_P (SUBREG_REG (in))
823 || GET_CODE (SUBREG_REG (in)) == PLUS
825 || (((GET_CODE (SUBREG_REG (in)) == REG
826 && REGNO (SUBREG_REG (in)) >= FIRST_PSEUDO_REGISTER)
827 || GET_CODE (SUBREG_REG (in)) == MEM)
828 && ((GET_MODE_SIZE (inmode)
829 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))))
830 #ifdef LOAD_EXTEND_OP
831 || (GET_MODE_SIZE (inmode) <= UNITS_PER_WORD
832 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in)))
834 && (GET_MODE_SIZE (inmode)
835 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (in))))
836 && INTEGRAL_MODE_P (GET_MODE (SUBREG_REG (in)))
837 && LOAD_EXTEND_OP (GET_MODE (SUBREG_REG (in))) != NIL)
840 || (GET_CODE (SUBREG_REG (in)) == REG
841 && REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER
842 /* The case where out is nonzero
843 is handled differently in the following statement. */
844 && (out == 0 || SUBREG_WORD (in) == 0)
845 && ((GET_MODE_SIZE (inmode) <= UNITS_PER_WORD
846 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in)))
848 && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in)))
850 != HARD_REGNO_NREGS (REGNO (SUBREG_REG (in)),
851 GET_MODE (SUBREG_REG (in)))))
852 || ! HARD_REGNO_MODE_OK ((REGNO (SUBREG_REG (in))
855 #ifdef SECONDARY_INPUT_RELOAD_CLASS
856 || (SECONDARY_INPUT_RELOAD_CLASS (class, inmode, in) != NO_REGS
857 && (SECONDARY_INPUT_RELOAD_CLASS (class,
858 GET_MODE (SUBREG_REG (in)),
862 #ifdef CLASS_CANNOT_CHANGE_SIZE
863 || (GET_CODE (SUBREG_REG (in)) == REG
864 && REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER
865 && (TEST_HARD_REG_BIT
866 (reg_class_contents[(int) CLASS_CANNOT_CHANGE_SIZE],
867 REGNO (SUBREG_REG (in))))
868 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in)))
869 != GET_MODE_SIZE (inmode)))
873 in_subreg_loc = inloc;
874 inloc = &SUBREG_REG (in);
876 #ifndef LOAD_EXTEND_OP
877 if (GET_CODE (in) == MEM)
878 /* This is supposed to happen only for paradoxical subregs made by
879 combine.c. (SUBREG (MEM)) isn't supposed to occur other ways. */
880 if (GET_MODE_SIZE (GET_MODE (in)) > GET_MODE_SIZE (inmode))
883 inmode = GET_MODE (in);
886 /* Similar issue for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where
887 either M1 is not valid for R or M2 is wider than a word but we only
888 need one word to store an M2-sized quantity in R.
890 However, we must reload the inner reg *as well as* the subreg in
893 if (in != 0 && GET_CODE (in) == SUBREG
894 && GET_CODE (SUBREG_REG (in)) == REG
895 && REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER
896 && (! HARD_REGNO_MODE_OK (REGNO (SUBREG_REG (in)), inmode)
897 || (GET_MODE_SIZE (inmode) <= UNITS_PER_WORD
898 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in)))
900 && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in)))
902 != HARD_REGNO_NREGS (REGNO (SUBREG_REG (in)),
903 GET_MODE (SUBREG_REG (in)))))))
905 /* This relies on the fact that emit_reload_insns outputs the
906 instructions for input reloads of type RELOAD_OTHER in the same
907 order as the reloads. Thus if the outer reload is also of type
908 RELOAD_OTHER, we are guaranteed that this inner reload will be
909 output before the outer reload. */
910 push_reload (SUBREG_REG (in), NULL_RTX, &SUBREG_REG (in), NULL_PTR,
911 GENERAL_REGS, VOIDmode, VOIDmode, 0, 0, opnum, type);
912 dont_remove_subreg = 1;
916 /* Similarly for paradoxical and problematical SUBREGs on the output.
917 Note that there is no reason we need worry about the previous value
918 of SUBREG_REG (out); even if wider than out,
919 storing in a subreg is entitled to clobber it all
920 (except in the case of STRICT_LOW_PART,
921 and in that case the constraint should label it input-output.) */
922 if (out != 0 && GET_CODE (out) == SUBREG && SUBREG_WORD (out) == 0
923 #ifdef CLASS_CANNOT_CHANGE_SIZE
924 && class != CLASS_CANNOT_CHANGE_SIZE
926 && (CONSTANT_P (SUBREG_REG (out))
928 || (((GET_CODE (SUBREG_REG (out)) == REG
929 && REGNO (SUBREG_REG (out)) >= FIRST_PSEUDO_REGISTER)
930 || GET_CODE (SUBREG_REG (out)) == MEM)
931 && ((GET_MODE_SIZE (outmode)
932 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (out))))))
933 || (GET_CODE (SUBREG_REG (out)) == REG
934 && REGNO (SUBREG_REG (out)) < FIRST_PSEUDO_REGISTER
935 && ((GET_MODE_SIZE (outmode) <= UNITS_PER_WORD
936 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (out)))
938 && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (out)))
940 != HARD_REGNO_NREGS (REGNO (SUBREG_REG (out)),
941 GET_MODE (SUBREG_REG (out)))))
942 || ! HARD_REGNO_MODE_OK ((REGNO (SUBREG_REG (out))
943 + SUBREG_WORD (out)),
945 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
946 || (SECONDARY_OUTPUT_RELOAD_CLASS (class, outmode, out) != NO_REGS
947 && (SECONDARY_OUTPUT_RELOAD_CLASS (class,
948 GET_MODE (SUBREG_REG (out)),
952 #ifdef CLASS_CANNOT_CHANGE_SIZE
953 || (GET_CODE (SUBREG_REG (out)) == REG
954 && REGNO (SUBREG_REG (out)) < FIRST_PSEUDO_REGISTER
955 && (TEST_HARD_REG_BIT
956 (reg_class_contents[(int) CLASS_CANNOT_CHANGE_SIZE],
957 REGNO (SUBREG_REG (out))))
958 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (out)))
959 != GET_MODE_SIZE (outmode)))
963 out_subreg_loc = outloc;
964 outloc = &SUBREG_REG (out);
966 #ifndef LOAD_EXTEND_OP
967 if (GET_CODE (out) == MEM
968 && GET_MODE_SIZE (GET_MODE (out)) > GET_MODE_SIZE (outmode))
971 outmode = GET_MODE (out);
974 /* Similar issue for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where
975 either M1 is not valid for R or M2 is wider than a word but we only
976 need one word to store an M2-sized quantity in R.
978 However, we must reload the inner reg *as well as* the subreg in
979 that case. In this case, the inner reg is an in-out reload. */
981 if (out != 0 && GET_CODE (out) == SUBREG
982 && GET_CODE (SUBREG_REG (out)) == REG
983 && REGNO (SUBREG_REG (out)) < FIRST_PSEUDO_REGISTER
984 && (! HARD_REGNO_MODE_OK (REGNO (SUBREG_REG (out)), outmode)
985 || (GET_MODE_SIZE (outmode) <= UNITS_PER_WORD
986 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (out)))
988 && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (out)))
990 != HARD_REGNO_NREGS (REGNO (SUBREG_REG (out)),
991 GET_MODE (SUBREG_REG (out)))))))
993 /* This relies on the fact that emit_reload_insns outputs the
994 instructions for output reloads of type RELOAD_OTHER in reverse
995 order of the reloads. Thus if the outer reload is also of type
996 RELOAD_OTHER, we are guaranteed that this inner reload will be
997 output after the outer reload. */
998 dont_remove_subreg = 1;
999 push_reload (SUBREG_REG (out), SUBREG_REG (out), &SUBREG_REG (out),
1000 &SUBREG_REG (out), ALL_REGS, VOIDmode, VOIDmode, 0, 0,
1001 opnum, RELOAD_OTHER);
1004 /* If IN appears in OUT, we can't share any input-only reload for IN. */
1005 if (in != 0 && out != 0 && GET_CODE (out) == MEM
1006 && (GET_CODE (in) == REG || GET_CODE (in) == MEM)
1007 && reg_overlap_mentioned_for_reload_p (in, XEXP (out, 0)))
1010 /* If IN is a SUBREG of a hard register, make a new REG. This
1011 simplifies some of the cases below. */
1013 if (in != 0 && GET_CODE (in) == SUBREG && GET_CODE (SUBREG_REG (in)) == REG
1014 && REGNO (SUBREG_REG (in)) < FIRST_PSEUDO_REGISTER
1015 && ! dont_remove_subreg)
1016 in = gen_rtx (REG, GET_MODE (in),
1017 REGNO (SUBREG_REG (in)) + SUBREG_WORD (in));
1019 /* Similarly for OUT. */
1020 if (out != 0 && GET_CODE (out) == SUBREG
1021 && GET_CODE (SUBREG_REG (out)) == REG
1022 && REGNO (SUBREG_REG (out)) < FIRST_PSEUDO_REGISTER
1023 && ! dont_remove_subreg)
1024 out = gen_rtx (REG, GET_MODE (out),
1025 REGNO (SUBREG_REG (out)) + SUBREG_WORD (out));
1027 /* Narrow down the class of register wanted if that is
1028 desirable on this machine for efficiency. */
1030 class = PREFERRED_RELOAD_CLASS (in, class);
1032 /* Output reloads may need analogous treatment, different in detail. */
1033 #ifdef PREFERRED_OUTPUT_RELOAD_CLASS
1035 class = PREFERRED_OUTPUT_RELOAD_CLASS (out, class);
1038 /* Make sure we use a class that can handle the actual pseudo
1039 inside any subreg. For example, on the 386, QImode regs
1040 can appear within SImode subregs. Although GENERAL_REGS
1041 can handle SImode, QImode needs a smaller class. */
1042 #ifdef LIMIT_RELOAD_CLASS
1044 class = LIMIT_RELOAD_CLASS (inmode, class);
1045 else if (in != 0 && GET_CODE (in) == SUBREG)
1046 class = LIMIT_RELOAD_CLASS (GET_MODE (SUBREG_REG (in)), class);
1049 class = LIMIT_RELOAD_CLASS (outmode, class);
1050 if (out != 0 && GET_CODE (out) == SUBREG)
1051 class = LIMIT_RELOAD_CLASS (GET_MODE (SUBREG_REG (out)), class);
1054 /* Verify that this class is at least possible for the mode that
1056 if (this_insn_is_asm)
1058 enum machine_mode mode;
1059 if (GET_MODE_SIZE (inmode) > GET_MODE_SIZE (outmode))
1063 if (mode == VOIDmode)
1065 error_for_asm (this_insn, "cannot reload integer constant operand in `asm'");
1070 outmode = word_mode;
1072 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
1073 if (HARD_REGNO_MODE_OK (i, mode)
1074 && TEST_HARD_REG_BIT (reg_class_contents[(int) class], i))
1076 int nregs = HARD_REGNO_NREGS (i, mode);
1079 for (j = 1; j < nregs; j++)
1080 if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class], i + j))
1085 if (i == FIRST_PSEUDO_REGISTER)
1087 error_for_asm (this_insn, "impossible register constraint in `asm'");
1092 if (class == NO_REGS)
1095 /* We can use an existing reload if the class is right
1096 and at least one of IN and OUT is a match
1097 and the other is at worst neutral.
1098 (A zero compared against anything is neutral.)
1100 If SMALL_REGISTER_CLASSES, don't use existing reloads unless they are
1101 for the same thing since that can cause us to need more reload registers
1102 than we otherwise would. */
1104 for (i = 0; i < n_reloads; i++)
1105 if ((reg_class_subset_p (class, reload_reg_class[i])
1106 || reg_class_subset_p (reload_reg_class[i], class))
1107 /* If the existing reload has a register, it must fit our class. */
1108 && (reload_reg_rtx[i] == 0
1109 || TEST_HARD_REG_BIT (reg_class_contents[(int) class],
1110 true_regnum (reload_reg_rtx[i])))
1111 && ((in != 0 && MATCHES (reload_in[i], in) && ! dont_share
1112 && (out == 0 || reload_out[i] == 0 || MATCHES (reload_out[i], out)))
1114 (out != 0 && MATCHES (reload_out[i], out)
1115 && (in == 0 || reload_in[i] == 0 || MATCHES (reload_in[i], in))))
1116 && (reg_class_size[(int) class] == 1
1117 #ifdef SMALL_REGISTER_CLASSES
1121 && MERGABLE_RELOADS (type, reload_when_needed[i],
1122 opnum, reload_opnum[i]))
1125 /* Reloading a plain reg for input can match a reload to postincrement
1126 that reg, since the postincrement's value is the right value.
1127 Likewise, it can match a preincrement reload, since we regard
1128 the preincrementation as happening before any ref in this insn
1129 to that register. */
1131 for (i = 0; i < n_reloads; i++)
1132 if ((reg_class_subset_p (class, reload_reg_class[i])
1133 || reg_class_subset_p (reload_reg_class[i], class))
1134 /* If the existing reload has a register, it must fit our class. */
1135 && (reload_reg_rtx[i] == 0
1136 || TEST_HARD_REG_BIT (reg_class_contents[(int) class],
1137 true_regnum (reload_reg_rtx[i])))
1138 && out == 0 && reload_out[i] == 0 && reload_in[i] != 0
1139 && ((GET_CODE (in) == REG
1140 && (GET_CODE (reload_in[i]) == POST_INC
1141 || GET_CODE (reload_in[i]) == POST_DEC
1142 || GET_CODE (reload_in[i]) == PRE_INC
1143 || GET_CODE (reload_in[i]) == PRE_DEC)
1144 && MATCHES (XEXP (reload_in[i], 0), in))
1146 (GET_CODE (reload_in[i]) == REG
1147 && (GET_CODE (in) == POST_INC
1148 || GET_CODE (in) == POST_DEC
1149 || GET_CODE (in) == PRE_INC
1150 || GET_CODE (in) == PRE_DEC)
1151 && MATCHES (XEXP (in, 0), reload_in[i])))
1152 && (reg_class_size[(int) class] == 1
1153 #ifdef SMALL_REGISTER_CLASSES
1157 && MERGABLE_RELOADS (type, reload_when_needed[i],
1158 opnum, reload_opnum[i]))
1160 /* Make sure reload_in ultimately has the increment,
1161 not the plain register. */
1162 if (GET_CODE (in) == REG)
1169 /* See if we need a secondary reload register to move between CLASS
1170 and IN or CLASS and OUT. Get the icode and push any required reloads
1171 needed for each of them if so. */
1173 #ifdef SECONDARY_INPUT_RELOAD_CLASS
1176 = push_secondary_reload (1, in, opnum, optional, class, inmode, type,
1177 &secondary_in_icode);
1180 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
1181 if (out != 0 && GET_CODE (out) != SCRATCH)
1182 secondary_out_reload
1183 = push_secondary_reload (0, out, opnum, optional, class, outmode,
1184 type, &secondary_out_icode);
1187 /* We found no existing reload suitable for re-use.
1188 So add an additional reload. */
1192 reload_out[i] = out;
1193 reload_reg_class[i] = class;
1194 reload_inmode[i] = inmode;
1195 reload_outmode[i] = outmode;
1196 reload_reg_rtx[i] = 0;
1197 reload_optional[i] = optional;
1199 reload_nocombine[i] = 0;
1200 reload_in_reg[i] = inloc ? *inloc : 0;
1201 reload_opnum[i] = opnum;
1202 reload_when_needed[i] = type;
1203 reload_secondary_in_reload[i] = secondary_in_reload;
1204 reload_secondary_out_reload[i] = secondary_out_reload;
1205 reload_secondary_in_icode[i] = secondary_in_icode;
1206 reload_secondary_out_icode[i] = secondary_out_icode;
1207 reload_secondary_p[i] = 0;
1211 #ifdef SECONDARY_MEMORY_NEEDED
1212 /* If a memory location is needed for the copy, make one. */
1213 if (in != 0 && GET_CODE (in) == REG
1214 && REGNO (in) < FIRST_PSEUDO_REGISTER
1215 && SECONDARY_MEMORY_NEEDED (REGNO_REG_CLASS (REGNO (in)),
1217 get_secondary_mem (in, inmode, opnum, type);
1219 if (out != 0 && GET_CODE (out) == REG
1220 && REGNO (out) < FIRST_PSEUDO_REGISTER
1221 && SECONDARY_MEMORY_NEEDED (class, REGNO_REG_CLASS (REGNO (out)),
1223 get_secondary_mem (out, outmode, opnum, type);
1228 /* We are reusing an existing reload,
1229 but we may have additional information for it.
1230 For example, we may now have both IN and OUT
1231 while the old one may have just one of them. */
1233 if (inmode != VOIDmode)
1234 reload_inmode[i] = inmode;
1235 if (outmode != VOIDmode)
1236 reload_outmode[i] = outmode;
1240 reload_out[i] = out;
1241 if (reg_class_subset_p (class, reload_reg_class[i]))
1242 reload_reg_class[i] = class;
1243 reload_optional[i] &= optional;
1244 if (MERGE_TO_OTHER (type, reload_when_needed[i],
1245 opnum, reload_opnum[i]))
1246 reload_when_needed[i] = RELOAD_OTHER;
1247 reload_opnum[i] = MIN (reload_opnum[i], opnum);
1250 /* If the ostensible rtx being reload differs from the rtx found
1251 in the location to substitute, this reload is not safe to combine
1252 because we cannot reliably tell whether it appears in the insn. */
1254 if (in != 0 && in != *inloc)
1255 reload_nocombine[i] = 1;
1258 /* This was replaced by changes in find_reloads_address_1 and the new
1259 function inc_for_reload, which go with a new meaning of reload_inc. */
1261 /* If this is an IN/OUT reload in an insn that sets the CC,
1262 it must be for an autoincrement. It doesn't work to store
1263 the incremented value after the insn because that would clobber the CC.
1264 So we must do the increment of the value reloaded from,
1265 increment it, store it back, then decrement again. */
1266 if (out != 0 && sets_cc0_p (PATTERN (this_insn)))
1270 reload_inc[i] = find_inc_amount (PATTERN (this_insn), in);
1271 /* If we did not find a nonzero amount-to-increment-by,
1272 that contradicts the belief that IN is being incremented
1273 in an address in this insn. */
1274 if (reload_inc[i] == 0)
1279 /* If we will replace IN and OUT with the reload-reg,
1280 record where they are located so that substitution need
1281 not do a tree walk. */
1283 if (replace_reloads)
1287 register struct replacement *r = &replacements[n_replacements++];
1289 r->subreg_loc = in_subreg_loc;
1293 if (outloc != 0 && outloc != inloc)
1295 register struct replacement *r = &replacements[n_replacements++];
1298 r->subreg_loc = out_subreg_loc;
1303 /* If this reload is just being introduced and it has both
1304 an incoming quantity and an outgoing quantity that are
1305 supposed to be made to match, see if either one of the two
1306 can serve as the place to reload into.
1308 If one of them is acceptable, set reload_reg_rtx[i]
1311 if (in != 0 && out != 0 && in != out && reload_reg_rtx[i] == 0)
1313 reload_reg_rtx[i] = find_dummy_reload (in, out, inloc, outloc,
1315 reload_reg_class[i], i);
1317 /* If the outgoing register already contains the same value
1318 as the incoming one, we can dispense with loading it.
1319 The easiest way to tell the caller that is to give a phony
1320 value for the incoming operand (same as outgoing one). */
1321 if (reload_reg_rtx[i] == out
1322 && (GET_CODE (in) == REG || CONSTANT_P (in))
1323 && 0 != find_equiv_reg (in, this_insn, 0, REGNO (out),
1324 static_reload_reg_p, i, inmode))
1328 /* If this is an input reload and the operand contains a register that
1329 dies in this insn and is used nowhere else, see if it is the right class
1330 to be used for this reload. Use it if so. (This occurs most commonly
1331 in the case of paradoxical SUBREGs and in-out reloads). We cannot do
1332 this if it is also an output reload that mentions the register unless
1333 the output is a SUBREG that clobbers an entire register.
1335 Note that the operand might be one of the spill regs, if it is a
1336 pseudo reg and we are in a block where spilling has not taken place.
1337 But if there is no spilling in this block, that is OK.
1338 An explicitly used hard reg cannot be a spill reg. */
1340 if (reload_reg_rtx[i] == 0 && in != 0)
1345 for (note = REG_NOTES (this_insn); note; note = XEXP (note, 1))
1346 if (REG_NOTE_KIND (note) == REG_DEAD
1347 && GET_CODE (XEXP (note, 0)) == REG
1348 && (regno = REGNO (XEXP (note, 0))) < FIRST_PSEUDO_REGISTER
1349 && reg_mentioned_p (XEXP (note, 0), in)
1350 && ! refers_to_regno_for_reload_p (regno,
1352 + HARD_REGNO_NREGS (regno,
1354 PATTERN (this_insn), inloc)
1355 /* If this is also an output reload, IN cannot be used as
1356 the reload register if it is set in this insn unless IN
1358 && (out == 0 || in == out
1359 || ! hard_reg_set_here_p (regno,
1361 + HARD_REGNO_NREGS (regno,
1363 PATTERN (this_insn)))
1364 /* ??? Why is this code so different from the previous?
1365 Is there any simple coherent way to describe the two together?
1366 What's going on here. */
1368 || (GET_CODE (in) == SUBREG
1369 && (((GET_MODE_SIZE (GET_MODE (in)) + (UNITS_PER_WORD - 1))
1371 == ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in)))
1372 + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD))))
1373 /* Make sure the operand fits in the reg that dies. */
1374 && GET_MODE_SIZE (inmode) <= GET_MODE_SIZE (GET_MODE (XEXP (note, 0)))
1375 && HARD_REGNO_MODE_OK (regno, inmode)
1376 && GET_MODE_SIZE (outmode) <= GET_MODE_SIZE (GET_MODE (XEXP (note, 0)))
1377 && HARD_REGNO_MODE_OK (regno, outmode)
1378 && TEST_HARD_REG_BIT (reg_class_contents[(int) class], regno)
1379 && !fixed_regs[regno])
1381 reload_reg_rtx[i] = gen_rtx (REG, inmode, regno);
1387 output_reloadnum = i;
1392 /* Record an additional place we must replace a value
1393 for which we have already recorded a reload.
1394 RELOADNUM is the value returned by push_reload
1395 when the reload was recorded.
1396 This is used in insn patterns that use match_dup. */
1399 push_replacement (loc, reloadnum, mode)
1402 enum machine_mode mode;
1404 if (replace_reloads)
1406 register struct replacement *r = &replacements[n_replacements++];
1407 r->what = reloadnum;
1414 /* Transfer all replacements that used to be in reload FROM to be in
1418 transfer_replacements (to, from)
1423 for (i = 0; i < n_replacements; i++)
1424 if (replacements[i].what == from)
1425 replacements[i].what = to;
1428 /* If there is only one output reload, and it is not for an earlyclobber
1429 operand, try to combine it with a (logically unrelated) input reload
1430 to reduce the number of reload registers needed.
1432 This is safe if the input reload does not appear in
1433 the value being output-reloaded, because this implies
1434 it is not needed any more once the original insn completes.
1436 If that doesn't work, see we can use any of the registers that
1437 die in this insn as a reload register. We can if it is of the right
1438 class and does not appear in the value being output-reloaded. */
1444 int output_reload = -1;
1445 int secondary_out = -1;
1448 /* Find the output reload; return unless there is exactly one
1449 and that one is mandatory. */
1451 for (i = 0; i < n_reloads; i++)
1452 if (reload_out[i] != 0)
1454 if (output_reload >= 0)
1459 if (output_reload < 0 || reload_optional[output_reload])
1462 /* An input-output reload isn't combinable. */
1464 if (reload_in[output_reload] != 0)
1467 /* If this reload is for an earlyclobber operand, we can't do anything. */
1468 if (earlyclobber_operand_p (reload_out[output_reload]))
1471 /* Check each input reload; can we combine it? */
1473 for (i = 0; i < n_reloads; i++)
1474 if (reload_in[i] && ! reload_optional[i] && ! reload_nocombine[i]
1475 /* Life span of this reload must not extend past main insn. */
1476 && reload_when_needed[i] != RELOAD_FOR_OUTPUT_ADDRESS
1477 && reload_when_needed[i] != RELOAD_OTHER
1478 && (CLASS_MAX_NREGS (reload_reg_class[i], reload_inmode[i])
1479 == CLASS_MAX_NREGS (reload_reg_class[output_reload],
1480 reload_outmode[output_reload]))
1481 && reload_inc[i] == 0
1482 && reload_reg_rtx[i] == 0
1483 #ifdef SECONDARY_MEMORY_NEEDED
1484 /* Don't combine two reloads with different secondary
1485 memory locations. */
1486 && (secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[i]] == 0
1487 || secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[output_reload]] == 0
1488 || rtx_equal_p (secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[i]],
1489 secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[output_reload]]))
1491 #ifdef SMALL_REGISTER_CLASSES
1492 && reload_reg_class[i] == reload_reg_class[output_reload]
1494 && (reg_class_subset_p (reload_reg_class[i],
1495 reload_reg_class[output_reload])
1496 || reg_class_subset_p (reload_reg_class[output_reload],
1497 reload_reg_class[i]))
1499 && (MATCHES (reload_in[i], reload_out[output_reload])
1500 /* Args reversed because the first arg seems to be
1501 the one that we imagine being modified
1502 while the second is the one that might be affected. */
1503 || (! reg_overlap_mentioned_for_reload_p (reload_out[output_reload],
1505 /* However, if the input is a register that appears inside
1506 the output, then we also can't share.
1507 Imagine (set (mem (reg 69)) (plus (reg 69) ...)).
1508 If the same reload reg is used for both reg 69 and the
1509 result to be stored in memory, then that result
1510 will clobber the address of the memory ref. */
1511 && ! (GET_CODE (reload_in[i]) == REG
1512 && reg_overlap_mentioned_for_reload_p (reload_in[i],
1513 reload_out[output_reload]))))
1514 && (reg_class_size[(int) reload_reg_class[i]]
1515 #ifdef SMALL_REGISTER_CLASSES
1519 /* We will allow making things slightly worse by combining an
1520 input and an output, but no worse than that. */
1521 && (reload_when_needed[i] == RELOAD_FOR_INPUT
1522 || reload_when_needed[i] == RELOAD_FOR_OUTPUT))
1526 /* We have found a reload to combine with! */
1527 reload_out[i] = reload_out[output_reload];
1528 reload_outmode[i] = reload_outmode[output_reload];
1529 /* Mark the old output reload as inoperative. */
1530 reload_out[output_reload] = 0;
1531 /* The combined reload is needed for the entire insn. */
1532 reload_when_needed[i] = RELOAD_OTHER;
1533 /* If the output reload had a secondary reload, copy it. */
1534 if (reload_secondary_out_reload[output_reload] != -1)
1536 reload_secondary_out_reload[i]
1537 = reload_secondary_out_reload[output_reload];
1538 reload_secondary_out_icode[i]
1539 = reload_secondary_out_icode[output_reload];
1542 #ifdef SECONDARY_MEMORY_NEEDED
1543 /* Copy any secondary MEM. */
1544 if (secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[output_reload]] != 0)
1545 secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[i]]
1546 = secondary_memlocs_elim[(int) reload_outmode[output_reload]][reload_opnum[output_reload]];
1548 /* If required, minimize the register class. */
1549 if (reg_class_subset_p (reload_reg_class[output_reload],
1550 reload_reg_class[i]))
1551 reload_reg_class[i] = reload_reg_class[output_reload];
1553 /* Transfer all replacements from the old reload to the combined. */
1554 for (j = 0; j < n_replacements; j++)
1555 if (replacements[j].what == output_reload)
1556 replacements[j].what = i;
1561 /* If this insn has only one operand that is modified or written (assumed
1562 to be the first), it must be the one corresponding to this reload. It
1563 is safe to use anything that dies in this insn for that output provided
1564 that it does not occur in the output (we already know it isn't an
1565 earlyclobber. If this is an asm insn, give up. */
1567 if (INSN_CODE (this_insn) == -1)
1570 for (i = 1; i < insn_n_operands[INSN_CODE (this_insn)]; i++)
1571 if (insn_operand_constraint[INSN_CODE (this_insn)][i][0] == '='
1572 || insn_operand_constraint[INSN_CODE (this_insn)][i][0] == '+')
1575 /* See if some hard register that dies in this insn and is not used in
1576 the output is the right class. Only works if the register we pick
1577 up can fully hold our output reload. */
1578 for (note = REG_NOTES (this_insn); note; note = XEXP (note, 1))
1579 if (REG_NOTE_KIND (note) == REG_DEAD
1580 && GET_CODE (XEXP (note, 0)) == REG
1581 && ! reg_overlap_mentioned_for_reload_p (XEXP (note, 0),
1582 reload_out[output_reload])
1583 && REGNO (XEXP (note, 0)) < FIRST_PSEUDO_REGISTER
1584 && HARD_REGNO_MODE_OK (REGNO (XEXP (note, 0)), reload_outmode[output_reload])
1585 && TEST_HARD_REG_BIT (reg_class_contents[(int) reload_reg_class[output_reload]],
1586 REGNO (XEXP (note, 0)))
1587 && (HARD_REGNO_NREGS (REGNO (XEXP (note, 0)), reload_outmode[output_reload])
1588 <= HARD_REGNO_NREGS (REGNO (XEXP (note, 0)), GET_MODE (XEXP (note, 0))))
1589 /* Ensure that a secondary or tertiary reload for this output
1590 won't want this register. */
1591 && ((secondary_out = reload_secondary_out_reload[output_reload]) == -1
1592 || (! (TEST_HARD_REG_BIT
1593 (reg_class_contents[(int) reload_reg_class[secondary_out]],
1594 REGNO (XEXP (note, 0))))
1595 && ((secondary_out = reload_secondary_out_reload[secondary_out]) == -1
1596 || ! (TEST_HARD_REG_BIT
1597 (reg_class_contents[(int) reload_reg_class[secondary_out]],
1598 REGNO (XEXP (note, 0)))))))
1599 && ! fixed_regs[REGNO (XEXP (note, 0))])
1601 reload_reg_rtx[output_reload] = gen_rtx (REG,
1602 reload_outmode[output_reload],
1603 REGNO (XEXP (note, 0)));
1608 /* Try to find a reload register for an in-out reload (expressions IN and OUT).
1609 See if one of IN and OUT is a register that may be used;
1610 this is desirable since a spill-register won't be needed.
1611 If so, return the register rtx that proves acceptable.
1613 INLOC and OUTLOC are locations where IN and OUT appear in the insn.
1614 CLASS is the register class required for the reload.
1616 If FOR_REAL is >= 0, it is the number of the reload,
1617 and in some cases when it can be discovered that OUT doesn't need
1618 to be computed, clear out reload_out[FOR_REAL].
1620 If FOR_REAL is -1, this should not be done, because this call
1621 is just to see if a register can be found, not to find and install it. */
1624 find_dummy_reload (real_in, real_out, inloc, outloc,
1625 inmode, outmode, class, for_real)
1626 rtx real_in, real_out;
1627 rtx *inloc, *outloc;
1628 enum machine_mode inmode, outmode;
1629 enum reg_class class;
1638 /* If operands exceed a word, we can't use either of them
1639 unless they have the same size. */
1640 if (GET_MODE_SIZE (outmode) != GET_MODE_SIZE (inmode)
1641 && (GET_MODE_SIZE (outmode) > UNITS_PER_WORD
1642 || GET_MODE_SIZE (inmode) > UNITS_PER_WORD))
1645 /* Find the inside of any subregs. */
1646 while (GET_CODE (out) == SUBREG)
1648 out_offset = SUBREG_WORD (out);
1649 out = SUBREG_REG (out);
1651 while (GET_CODE (in) == SUBREG)
1653 in_offset = SUBREG_WORD (in);
1654 in = SUBREG_REG (in);
1657 /* Narrow down the reg class, the same way push_reload will;
1658 otherwise we might find a dummy now, but push_reload won't. */
1659 class = PREFERRED_RELOAD_CLASS (in, class);
1661 /* See if OUT will do. */
1662 if (GET_CODE (out) == REG
1663 && REGNO (out) < FIRST_PSEUDO_REGISTER)
1665 register int regno = REGNO (out) + out_offset;
1666 int nwords = HARD_REGNO_NREGS (regno, outmode);
1669 /* When we consider whether the insn uses OUT,
1670 ignore references within IN. They don't prevent us
1671 from copying IN into OUT, because those refs would
1672 move into the insn that reloads IN.
1674 However, we only ignore IN in its role as this reload.
1675 If the insn uses IN elsewhere and it contains OUT,
1676 that counts. We can't be sure it's the "same" operand
1677 so it might not go through this reload. */
1679 *inloc = const0_rtx;
1681 if (regno < FIRST_PSEUDO_REGISTER
1682 /* A fixed reg that can overlap other regs better not be used
1683 for reloading in any way. */
1684 #ifdef OVERLAPPING_REGNO_P
1685 && ! (fixed_regs[regno] && OVERLAPPING_REGNO_P (regno))
1687 && ! refers_to_regno_for_reload_p (regno, regno + nwords,
1688 PATTERN (this_insn), outloc))
1691 for (i = 0; i < nwords; i++)
1692 if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class],
1698 if (GET_CODE (real_out) == REG)
1701 value = gen_rtx (REG, outmode, regno);
1708 /* Consider using IN if OUT was not acceptable
1709 or if OUT dies in this insn (like the quotient in a divmod insn).
1710 We can't use IN unless it is dies in this insn,
1711 which means we must know accurately which hard regs are live.
1712 Also, the result can't go in IN if IN is used within OUT. */
1713 if (hard_regs_live_known
1714 && GET_CODE (in) == REG
1715 && REGNO (in) < FIRST_PSEUDO_REGISTER
1717 || find_reg_note (this_insn, REG_UNUSED, real_out))
1718 && find_reg_note (this_insn, REG_DEAD, real_in)
1719 && !fixed_regs[REGNO (in)]
1720 && HARD_REGNO_MODE_OK (REGNO (in),
1721 /* The only case where out and real_out might
1722 have different modes is where real_out
1723 is a subreg, and in that case, out
1725 (GET_MODE (out) != VOIDmode
1726 ? GET_MODE (out) : outmode)))
1728 register int regno = REGNO (in) + in_offset;
1729 int nwords = HARD_REGNO_NREGS (regno, inmode);
1731 if (! refers_to_regno_for_reload_p (regno, regno + nwords, out, NULL_PTR)
1732 && ! hard_reg_set_here_p (regno, regno + nwords,
1733 PATTERN (this_insn)))
1736 for (i = 0; i < nwords; i++)
1737 if (! TEST_HARD_REG_BIT (reg_class_contents[(int) class],
1743 /* If we were going to use OUT as the reload reg
1744 and changed our mind, it means OUT is a dummy that
1745 dies here. So don't bother copying value to it. */
1746 if (for_real >= 0 && value == real_out)
1747 reload_out[for_real] = 0;
1748 if (GET_CODE (real_in) == REG)
1751 value = gen_rtx (REG, inmode, regno);
1759 /* This page contains subroutines used mainly for determining
1760 whether the IN or an OUT of a reload can serve as the
1763 /* Return 1 if X is an operand of an insn that is being earlyclobbered. */
1766 earlyclobber_operand_p (x)
1771 for (i = 0; i < n_earlyclobbers; i++)
1772 if (reload_earlyclobbers[i] == x)
1778 /* Return 1 if expression X alters a hard reg in the range
1779 from BEG_REGNO (inclusive) to END_REGNO (exclusive),
1780 either explicitly or in the guise of a pseudo-reg allocated to REGNO.
1781 X should be the body of an instruction. */
1784 hard_reg_set_here_p (beg_regno, end_regno, x)
1785 register int beg_regno, end_regno;
1788 if (GET_CODE (x) == SET || GET_CODE (x) == CLOBBER)
1790 register rtx op0 = SET_DEST (x);
1791 while (GET_CODE (op0) == SUBREG)
1792 op0 = SUBREG_REG (op0);
1793 if (GET_CODE (op0) == REG)
1795 register int r = REGNO (op0);
1796 /* See if this reg overlaps range under consideration. */
1798 && r + HARD_REGNO_NREGS (r, GET_MODE (op0)) > beg_regno)
1802 else if (GET_CODE (x) == PARALLEL)
1804 register int i = XVECLEN (x, 0) - 1;
1806 if (hard_reg_set_here_p (beg_regno, end_regno, XVECEXP (x, 0, i)))
1813 /* Return 1 if ADDR is a valid memory address for mode MODE,
1814 and check that each pseudo reg has the proper kind of
1818 strict_memory_address_p (mode, addr)
1819 enum machine_mode mode;
1822 GO_IF_LEGITIMATE_ADDRESS (mode, addr, win);
1829 /* Like rtx_equal_p except that it allows a REG and a SUBREG to match
1830 if they are the same hard reg, and has special hacks for
1831 autoincrement and autodecrement.
1832 This is specifically intended for find_reloads to use
1833 in determining whether two operands match.
1834 X is the operand whose number is the lower of the two.
1836 The value is 2 if Y contains a pre-increment that matches
1837 a non-incrementing address in X. */
1839 /* ??? To be completely correct, we should arrange to pass
1840 for X the output operand and for Y the input operand.
1841 For now, we assume that the output operand has the lower number
1842 because that is natural in (SET output (... input ...)). */
1845 operands_match_p (x, y)
1849 register RTX_CODE code = GET_CODE (x);
1855 if ((code == REG || (code == SUBREG && GET_CODE (SUBREG_REG (x)) == REG))
1856 && (GET_CODE (y) == REG || (GET_CODE (y) == SUBREG
1857 && GET_CODE (SUBREG_REG (y)) == REG)))
1863 i = REGNO (SUBREG_REG (x));
1864 if (i >= FIRST_PSEUDO_REGISTER)
1866 i += SUBREG_WORD (x);
1871 if (GET_CODE (y) == SUBREG)
1873 j = REGNO (SUBREG_REG (y));
1874 if (j >= FIRST_PSEUDO_REGISTER)
1876 j += SUBREG_WORD (y);
1881 /* On a WORDS_BIG_ENDIAN machine, point to the last register of a
1882 multiple hard register group, so that for example (reg:DI 0) and
1883 (reg:SI 1) will be considered the same register. */
1884 if (WORDS_BIG_ENDIAN && GET_MODE_SIZE (GET_MODE (x)) > UNITS_PER_WORD
1885 && i < FIRST_PSEUDO_REGISTER)
1886 i += (GET_MODE_SIZE (GET_MODE (x)) / UNITS_PER_WORD) - 1;
1887 if (WORDS_BIG_ENDIAN && GET_MODE_SIZE (GET_MODE (y)) > UNITS_PER_WORD
1888 && j < FIRST_PSEUDO_REGISTER)
1889 j += (GET_MODE_SIZE (GET_MODE (y)) / UNITS_PER_WORD) - 1;
1893 /* If two operands must match, because they are really a single
1894 operand of an assembler insn, then two postincrements are invalid
1895 because the assembler insn would increment only once.
1896 On the other hand, an postincrement matches ordinary indexing
1897 if the postincrement is the output operand. */
1898 if (code == POST_DEC || code == POST_INC)
1899 return operands_match_p (XEXP (x, 0), y);
1900 /* Two preincrements are invalid
1901 because the assembler insn would increment only once.
1902 On the other hand, an preincrement matches ordinary indexing
1903 if the preincrement is the input operand.
1904 In this case, return 2, since some callers need to do special
1905 things when this happens. */
1906 if (GET_CODE (y) == PRE_DEC || GET_CODE (y) == PRE_INC)
1907 return operands_match_p (x, XEXP (y, 0)) ? 2 : 0;
1911 /* Now we have disposed of all the cases
1912 in which different rtx codes can match. */
1913 if (code != GET_CODE (y))
1915 if (code == LABEL_REF)
1916 return XEXP (x, 0) == XEXP (y, 0);
1917 if (code == SYMBOL_REF)
1918 return XSTR (x, 0) == XSTR (y, 0);
1920 /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent. */
1922 if (GET_MODE (x) != GET_MODE (y))
1925 /* Compare the elements. If any pair of corresponding elements
1926 fail to match, return 0 for the whole things. */
1929 fmt = GET_RTX_FORMAT (code);
1930 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
1936 if (XWINT (x, i) != XWINT (y, i))
1941 if (XINT (x, i) != XINT (y, i))
1946 val = operands_match_p (XEXP (x, i), XEXP (y, i));
1949 /* If any subexpression returns 2,
1950 we should return 2 if we are successful. */
1958 /* It is believed that rtx's at this level will never
1959 contain anything but integers and other rtx's,
1960 except for within LABEL_REFs and SYMBOL_REFs. */
1965 return 1 + success_2;
1968 /* Return the number of times character C occurs in string S. */
1971 n_occurrences (c, s)
1981 /* Describe the range of registers or memory referenced by X.
1982 If X is a register, set REG_FLAG and put the first register
1983 number into START and the last plus one into END.
1984 If X is a memory reference, put a base address into BASE
1985 and a range of integer offsets into START and END.
1986 If X is pushing on the stack, we can assume it causes no trouble,
1987 so we set the SAFE field. */
1989 static struct decomposition
1993 struct decomposition val;
1998 if (GET_CODE (x) == MEM)
2000 rtx base, offset = 0;
2001 rtx addr = XEXP (x, 0);
2003 if (GET_CODE (addr) == PRE_DEC || GET_CODE (addr) == PRE_INC
2004 || GET_CODE (addr) == POST_DEC || GET_CODE (addr) == POST_INC)
2006 val.base = XEXP (addr, 0);
2007 val.start = - GET_MODE_SIZE (GET_MODE (x));
2008 val.end = GET_MODE_SIZE (GET_MODE (x));
2009 val.safe = REGNO (val.base) == STACK_POINTER_REGNUM;
2013 if (GET_CODE (addr) == CONST)
2015 addr = XEXP (addr, 0);
2018 if (GET_CODE (addr) == PLUS)
2020 if (CONSTANT_P (XEXP (addr, 0)))
2022 base = XEXP (addr, 1);
2023 offset = XEXP (addr, 0);
2025 else if (CONSTANT_P (XEXP (addr, 1)))
2027 base = XEXP (addr, 0);
2028 offset = XEXP (addr, 1);
2035 offset = const0_rtx;
2037 if (GET_CODE (offset) == CONST)
2038 offset = XEXP (offset, 0);
2039 if (GET_CODE (offset) == PLUS)
2041 if (GET_CODE (XEXP (offset, 0)) == CONST_INT)
2043 base = gen_rtx (PLUS, GET_MODE (base), base, XEXP (offset, 1));
2044 offset = XEXP (offset, 0);
2046 else if (GET_CODE (XEXP (offset, 1)) == CONST_INT)
2048 base = gen_rtx (PLUS, GET_MODE (base), base, XEXP (offset, 0));
2049 offset = XEXP (offset, 1);
2053 base = gen_rtx (PLUS, GET_MODE (base), base, offset);
2054 offset = const0_rtx;
2057 else if (GET_CODE (offset) != CONST_INT)
2059 base = gen_rtx (PLUS, GET_MODE (base), base, offset);
2060 offset = const0_rtx;
2063 if (all_const && GET_CODE (base) == PLUS)
2064 base = gen_rtx (CONST, GET_MODE (base), base);
2066 if (GET_CODE (offset) != CONST_INT)
2069 val.start = INTVAL (offset);
2070 val.end = val.start + GET_MODE_SIZE (GET_MODE (x));
2074 else if (GET_CODE (x) == REG)
2077 val.start = true_regnum (x);
2080 /* A pseudo with no hard reg. */
2081 val.start = REGNO (x);
2082 val.end = val.start + 1;
2086 val.end = val.start + HARD_REGNO_NREGS (val.start, GET_MODE (x));
2088 else if (GET_CODE (x) == SUBREG)
2090 if (GET_CODE (SUBREG_REG (x)) != REG)
2091 /* This could be more precise, but it's good enough. */
2092 return decompose (SUBREG_REG (x));
2094 val.start = true_regnum (x);
2096 return decompose (SUBREG_REG (x));
2099 val.end = val.start + HARD_REGNO_NREGS (val.start, GET_MODE (x));
2101 else if (CONSTANT_P (x)
2102 /* This hasn't been assigned yet, so it can't conflict yet. */
2103 || GET_CODE (x) == SCRATCH)
2110 /* Return 1 if altering Y will not modify the value of X.
2111 Y is also described by YDATA, which should be decompose (Y). */
2114 immune_p (x, y, ydata)
2116 struct decomposition ydata;
2118 struct decomposition xdata;
2121 return !refers_to_regno_for_reload_p (ydata.start, ydata.end, x, NULL_PTR);
2125 if (GET_CODE (y) != MEM)
2127 /* If Y is memory and X is not, Y can't affect X. */
2128 if (GET_CODE (x) != MEM)
2131 xdata = decompose (x);
2133 if (! rtx_equal_p (xdata.base, ydata.base))
2135 /* If bases are distinct symbolic constants, there is no overlap. */
2136 if (CONSTANT_P (xdata.base) && CONSTANT_P (ydata.base))
2138 /* Constants and stack slots never overlap. */
2139 if (CONSTANT_P (xdata.base)
2140 && (ydata.base == frame_pointer_rtx
2141 || ydata.base == hard_frame_pointer_rtx
2142 || ydata.base == stack_pointer_rtx))
2144 if (CONSTANT_P (ydata.base)
2145 && (xdata.base == frame_pointer_rtx
2146 || xdata.base == hard_frame_pointer_rtx
2147 || xdata.base == stack_pointer_rtx))
2149 /* If either base is variable, we don't know anything. */
2154 return (xdata.start >= ydata.end || ydata.start >= xdata.end);
2157 /* Similar, but calls decompose. */
2160 safe_from_earlyclobber (op, clobber)
2163 struct decomposition early_data;
2165 early_data = decompose (clobber);
2166 return immune_p (op, clobber, early_data);
2169 /* Main entry point of this file: search the body of INSN
2170 for values that need reloading and record them with push_reload.
2171 REPLACE nonzero means record also where the values occur
2172 so that subst_reloads can be used.
2174 IND_LEVELS says how many levels of indirection are supported by this
2175 machine; a value of zero means that a memory reference is not a valid
2178 LIVE_KNOWN says we have valid information about which hard
2179 regs are live at each point in the program; this is true when
2180 we are called from global_alloc but false when stupid register
2181 allocation has been done.
2183 RELOAD_REG_P if nonzero is a vector indexed by hard reg number
2184 which is nonnegative if the reg has been commandeered for reloading into.
2185 It is copied into STATIC_RELOAD_REG_P and referenced from there
2186 by various subroutines. */
2189 find_reloads (insn, replace, ind_levels, live_known, reload_reg_p)
2191 int replace, ind_levels;
2193 short *reload_reg_p;
2195 #ifdef REGISTER_CONSTRAINTS
2197 register int insn_code_number;
2200 /* These are the constraints for the insn. We don't change them. */
2201 char *constraints1[MAX_RECOG_OPERANDS];
2202 /* These start out as the constraints for the insn
2203 and they are chewed up as we consider alternatives. */
2204 char *constraints[MAX_RECOG_OPERANDS];
2205 /* These are the preferred classes for an operand, or NO_REGS if it isn't
2207 enum reg_class preferred_class[MAX_RECOG_OPERANDS];
2208 char pref_or_nothing[MAX_RECOG_OPERANDS];
2209 /* Nonzero for a MEM operand whose entire address needs a reload. */
2210 int address_reloaded[MAX_RECOG_OPERANDS];
2211 /* Value of enum reload_type to use for operand. */
2212 enum reload_type operand_type[MAX_RECOG_OPERANDS];
2213 /* Value of enum reload_type to use within address of operand. */
2214 enum reload_type address_type[MAX_RECOG_OPERANDS];
2215 /* Save the usage of each operand. */
2216 enum reload_usage { RELOAD_READ, RELOAD_READ_WRITE, RELOAD_WRITE } modified[MAX_RECOG_OPERANDS];
2217 int no_input_reloads = 0, no_output_reloads = 0;
2219 int this_alternative[MAX_RECOG_OPERANDS];
2220 char this_alternative_win[MAX_RECOG_OPERANDS];
2221 char this_alternative_offmemok[MAX_RECOG_OPERANDS];
2222 char this_alternative_earlyclobber[MAX_RECOG_OPERANDS];
2223 int this_alternative_matches[MAX_RECOG_OPERANDS];
2225 int goal_alternative[MAX_RECOG_OPERANDS];
2226 int this_alternative_number;
2227 int goal_alternative_number;
2228 int operand_reloadnum[MAX_RECOG_OPERANDS];
2229 int goal_alternative_matches[MAX_RECOG_OPERANDS];
2230 int goal_alternative_matched[MAX_RECOG_OPERANDS];
2231 char goal_alternative_win[MAX_RECOG_OPERANDS];
2232 char goal_alternative_offmemok[MAX_RECOG_OPERANDS];
2233 char goal_alternative_earlyclobber[MAX_RECOG_OPERANDS];
2234 int goal_alternative_swapped;
2237 char operands_match[MAX_RECOG_OPERANDS][MAX_RECOG_OPERANDS];
2238 rtx substed_operand[MAX_RECOG_OPERANDS];
2239 rtx body = PATTERN (insn);
2240 rtx set = single_set (insn);
2241 int goal_earlyclobber, this_earlyclobber;
2242 enum machine_mode operand_mode[MAX_RECOG_OPERANDS];
2245 this_insn_is_asm = 0; /* Tentative. */
2249 n_earlyclobbers = 0;
2250 replace_reloads = replace;
2251 hard_regs_live_known = live_known;
2252 static_reload_reg_p = reload_reg_p;
2254 /* JUMP_INSNs and CALL_INSNs are not allowed to have any output reloads;
2255 neither are insns that SET cc0. Insns that use CC0 are not allowed
2256 to have any input reloads. */
2257 if (GET_CODE (insn) == JUMP_INSN || GET_CODE (insn) == CALL_INSN)
2258 no_output_reloads = 1;
2261 if (reg_referenced_p (cc0_rtx, PATTERN (insn)))
2262 no_input_reloads = 1;
2263 if (reg_set_p (cc0_rtx, PATTERN (insn)))
2264 no_output_reloads = 1;
2267 #ifdef SECONDARY_MEMORY_NEEDED
2268 /* The eliminated forms of any secondary memory locations are per-insn, so
2269 clear them out here. */
2271 bzero ((char *) secondary_memlocs_elim, sizeof secondary_memlocs_elim);
2274 /* Find what kind of insn this is. NOPERANDS gets number of operands.
2275 Make OPERANDS point to a vector of operand values.
2276 Make OPERAND_LOCS point to a vector of pointers to
2277 where the operands were found.
2278 Fill CONSTRAINTS and CONSTRAINTS1 with pointers to the
2279 constraint-strings for this insn.
2280 Return if the insn needs no reload processing. */
2282 switch (GET_CODE (body))
2292 /* Dispose quickly of (set (reg..) (reg..)) if both have hard regs and it
2293 is cheap to move between them. If it is not, there may not be an insn
2294 to do the copy, so we may need a reload. */
2295 if (GET_CODE (SET_DEST (body)) == REG
2296 && REGNO (SET_DEST (body)) < FIRST_PSEUDO_REGISTER
2297 && GET_CODE (SET_SRC (body)) == REG
2298 && REGNO (SET_SRC (body)) < FIRST_PSEUDO_REGISTER
2299 && REGISTER_MOVE_COST (REGNO_REG_CLASS (REGNO (SET_SRC (body))),
2300 REGNO_REG_CLASS (REGNO (SET_DEST (body)))) == 2)
2304 reload_n_operands = noperands = asm_noperands (body);
2307 /* This insn is an `asm' with operands. */
2309 insn_code_number = -1;
2310 this_insn_is_asm = 1;
2312 /* expand_asm_operands makes sure there aren't too many operands. */
2313 if (noperands > MAX_RECOG_OPERANDS)
2316 /* Now get the operand values and constraints out of the insn. */
2318 decode_asm_operands (body, recog_operand, recog_operand_loc,
2319 constraints, operand_mode);
2322 bcopy ((char *) constraints, (char *) constraints1,
2323 noperands * sizeof (char *));
2324 n_alternatives = n_occurrences (',', constraints[0]) + 1;
2325 for (i = 1; i < noperands; i++)
2326 if (n_alternatives != n_occurrences (',', constraints[i]) + 1)
2328 error_for_asm (insn, "operand constraints differ in number of alternatives");
2329 /* Avoid further trouble with this insn. */
2330 PATTERN (insn) = gen_rtx (USE, VOIDmode, const0_rtx);
2339 /* Ordinary insn: recognize it, get the operands via insn_extract
2340 and get the constraints. */
2342 insn_code_number = recog_memoized (insn);
2343 if (insn_code_number < 0)
2344 fatal_insn_not_found (insn);
2346 reload_n_operands = noperands = insn_n_operands[insn_code_number];
2347 n_alternatives = insn_n_alternatives[insn_code_number];
2348 /* Just return "no reloads" if insn has no operands with constraints. */
2349 if (n_alternatives == 0)
2351 insn_extract (insn);
2352 for (i = 0; i < noperands; i++)
2354 constraints[i] = constraints1[i]
2355 = insn_operand_constraint[insn_code_number][i];
2356 operand_mode[i] = insn_operand_mode[insn_code_number][i];
2365 /* If we will need to know, later, whether some pair of operands
2366 are the same, we must compare them now and save the result.
2367 Reloading the base and index registers will clobber them
2368 and afterward they will fail to match. */
2370 for (i = 0; i < noperands; i++)
2375 substed_operand[i] = recog_operand[i];
2378 modified[i] = RELOAD_READ;
2380 /* Scan this operand's constraint to see if it is an output operand,
2381 an in-out operand, is commutative, or should match another. */
2386 modified[i] = RELOAD_WRITE;
2388 modified[i] = RELOAD_READ_WRITE;
2391 /* The last operand should not be marked commutative. */
2392 if (i == noperands - 1)
2394 if (this_insn_is_asm)
2395 warning_for_asm (this_insn,
2396 "`%%' constraint used with last operand");
2403 else if (c >= '0' && c <= '9')
2406 operands_match[c][i]
2407 = operands_match_p (recog_operand[c], recog_operand[i]);
2409 /* An operand may not match itself. */
2412 if (this_insn_is_asm)
2413 warning_for_asm (this_insn,
2414 "operand %d has constraint %d", i, c);
2419 /* If C can be commuted with C+1, and C might need to match I,
2420 then C+1 might also need to match I. */
2421 if (commutative >= 0)
2423 if (c == commutative || c == commutative + 1)
2425 int other = c + (c == commutative ? 1 : -1);
2426 operands_match[other][i]
2427 = operands_match_p (recog_operand[other], recog_operand[i]);
2429 if (i == commutative || i == commutative + 1)
2431 int other = i + (i == commutative ? 1 : -1);
2432 operands_match[c][other]
2433 = operands_match_p (recog_operand[c], recog_operand[other]);
2435 /* Note that C is supposed to be less than I.
2436 No need to consider altering both C and I because in
2437 that case we would alter one into the other. */
2443 /* Examine each operand that is a memory reference or memory address
2444 and reload parts of the addresses into index registers.
2445 Also here any references to pseudo regs that didn't get hard regs
2446 but are equivalent to constants get replaced in the insn itself
2447 with those constants. Nobody will ever see them again.
2449 Finally, set up the preferred classes of each operand. */
2451 for (i = 0; i < noperands; i++)
2453 register RTX_CODE code = GET_CODE (recog_operand[i]);
2455 address_reloaded[i] = 0;
2456 operand_type[i] = (modified[i] == RELOAD_READ ? RELOAD_FOR_INPUT
2457 : modified[i] == RELOAD_WRITE ? RELOAD_FOR_OUTPUT
2460 = (modified[i] == RELOAD_READ ? RELOAD_FOR_INPUT_ADDRESS
2461 : modified[i] == RELOAD_WRITE ? RELOAD_FOR_OUTPUT_ADDRESS
2464 if (*constraints[i] == 0)
2465 /* Ignore things like match_operator operands. */
2467 else if (constraints[i][0] == 'p')
2469 find_reloads_address (VOIDmode, NULL_PTR,
2470 recog_operand[i], recog_operand_loc[i],
2471 i, operand_type[i], ind_levels);
2472 substed_operand[i] = recog_operand[i] = *recog_operand_loc[i];
2474 else if (code == MEM)
2476 if (find_reloads_address (GET_MODE (recog_operand[i]),
2477 recog_operand_loc[i],
2478 XEXP (recog_operand[i], 0),
2479 &XEXP (recog_operand[i], 0),
2480 i, address_type[i], ind_levels))
2481 address_reloaded[i] = 1;
2482 substed_operand[i] = recog_operand[i] = *recog_operand_loc[i];
2484 else if (code == SUBREG)
2485 substed_operand[i] = recog_operand[i] = *recog_operand_loc[i]
2486 = find_reloads_toplev (recog_operand[i], i, address_type[i],
2489 && &SET_DEST (set) == recog_operand_loc[i]);
2490 else if (code == PLUS)
2491 /* We can get a PLUS as an "operand" as a result of
2492 register elimination. See eliminate_regs and gen_reload. */
2493 substed_operand[i] = recog_operand[i] = *recog_operand_loc[i]
2494 = find_reloads_toplev (recog_operand[i], i, address_type[i],
2496 else if (code == REG)
2498 /* This is equivalent to calling find_reloads_toplev.
2499 The code is duplicated for speed.
2500 When we find a pseudo always equivalent to a constant,
2501 we replace it by the constant. We must be sure, however,
2502 that we don't try to replace it in the insn in which it
2504 register int regno = REGNO (recog_operand[i]);
2505 if (reg_equiv_constant[regno] != 0
2506 && (set == 0 || &SET_DEST (set) != recog_operand_loc[i]))
2507 substed_operand[i] = recog_operand[i]
2508 = reg_equiv_constant[regno];
2509 #if 0 /* This might screw code in reload1.c to delete prior output-reload
2510 that feeds this insn. */
2511 if (reg_equiv_mem[regno] != 0)
2512 substed_operand[i] = recog_operand[i]
2513 = reg_equiv_mem[regno];
2515 if (reg_equiv_address[regno] != 0)
2517 /* If reg_equiv_address is not a constant address, copy it,
2518 since it may be shared. */
2519 /* We must rerun eliminate_regs, in case the elimination
2520 offsets have changed. */
2521 rtx address = XEXP (eliminate_regs (reg_equiv_memory_loc[regno],
2525 if (rtx_varies_p (address))
2526 address = copy_rtx (address);
2528 /* If this is an output operand, we must output a CLOBBER
2529 after INSN so find_equiv_reg knows REGNO is being written.
2530 Mark this insn specially, do we can put our output reloads
2533 if (modified[i] != RELOAD_READ)
2534 PUT_MODE (emit_insn_after (gen_rtx (CLOBBER, VOIDmode,
2539 *recog_operand_loc[i] = recog_operand[i]
2540 = gen_rtx (MEM, GET_MODE (recog_operand[i]), address);
2541 RTX_UNCHANGING_P (recog_operand[i])
2542 = RTX_UNCHANGING_P (regno_reg_rtx[regno]);
2543 find_reloads_address (GET_MODE (recog_operand[i]),
2544 recog_operand_loc[i],
2545 XEXP (recog_operand[i], 0),
2546 &XEXP (recog_operand[i], 0),
2547 i, address_type[i], ind_levels);
2548 substed_operand[i] = recog_operand[i] = *recog_operand_loc[i];
2551 /* If the operand is still a register (we didn't replace it with an
2552 equivalent), get the preferred class to reload it into. */
2553 code = GET_CODE (recog_operand[i]);
2555 = ((code == REG && REGNO (recog_operand[i]) >= FIRST_PSEUDO_REGISTER)
2556 ? reg_preferred_class (REGNO (recog_operand[i])) : NO_REGS);
2558 = (code == REG && REGNO (recog_operand[i]) >= FIRST_PSEUDO_REGISTER
2559 && reg_alternate_class (REGNO (recog_operand[i])) == NO_REGS);
2562 /* If this is simply a copy from operand 1 to operand 0, merge the
2563 preferred classes for the operands. */
2564 if (set != 0 && noperands >= 2 && recog_operand[0] == SET_DEST (set)
2565 && recog_operand[1] == SET_SRC (set))
2567 preferred_class[0] = preferred_class[1]
2568 = reg_class_subunion[(int) preferred_class[0]][(int) preferred_class[1]];
2569 pref_or_nothing[0] |= pref_or_nothing[1];
2570 pref_or_nothing[1] |= pref_or_nothing[0];
2573 /* Now see what we need for pseudo-regs that didn't get hard regs
2574 or got the wrong kind of hard reg. For this, we must consider
2575 all the operands together against the register constraints. */
2577 best = MAX_RECOG_OPERANDS + 300;
2580 goal_alternative_swapped = 0;
2583 /* The constraints are made of several alternatives.
2584 Each operand's constraint looks like foo,bar,... with commas
2585 separating the alternatives. The first alternatives for all
2586 operands go together, the second alternatives go together, etc.
2588 First loop over alternatives. */
2590 for (this_alternative_number = 0;
2591 this_alternative_number < n_alternatives;
2592 this_alternative_number++)
2594 /* Loop over operands for one constraint alternative. */
2595 /* LOSERS counts those that don't fit this alternative
2596 and would require loading. */
2598 /* BAD is set to 1 if it some operand can't fit this alternative
2599 even after reloading. */
2601 /* REJECT is a count of how undesirable this alternative says it is
2602 if any reloading is required. If the alternative matches exactly
2603 then REJECT is ignored, but otherwise it gets this much
2604 counted against it in addition to the reloading needed. Each
2605 ? counts three times here since we want the disparaging caused by
2606 a bad register class to only count 1/3 as much. */
2609 this_earlyclobber = 0;
2611 for (i = 0; i < noperands; i++)
2613 register char *p = constraints[i];
2614 register int win = 0;
2615 /* 0 => this operand can be reloaded somehow for this alternative */
2617 /* 0 => this operand can be reloaded if the alternative allows regs. */
2620 register rtx operand = recog_operand[i];
2622 /* Nonzero means this is a MEM that must be reloaded into a reg
2623 regardless of what the constraint says. */
2624 int force_reload = 0;
2626 /* Nonzero if a constant forced into memory would be OK for this
2629 int earlyclobber = 0;
2631 /* If the operand is a SUBREG, extract
2632 the REG or MEM (or maybe even a constant) within.
2633 (Constants can occur as a result of reg_equiv_constant.) */
2635 while (GET_CODE (operand) == SUBREG)
2637 offset += SUBREG_WORD (operand);
2638 operand = SUBREG_REG (operand);
2639 /* Force reload if this is a constant or PLUS or if there may may
2640 be a problem accessing OPERAND in the outer mode. */
2641 if (CONSTANT_P (operand)
2642 || GET_CODE (operand) == PLUS
2643 /* We must force a reload of paradoxical SUBREGs
2644 of a MEM because the alignment of the inner value
2645 may not be enough to do the outer reference. On
2646 big-endian machines, it may also reference outside
2649 On machines that extend byte operations and we have a
2650 SUBREG where both the inner and outer modes are no wider
2651 than a word and the inner mode is narrower, is integral,
2652 and gets extended when loaded from memory, combine.c has
2653 made assumptions about the behavior of the machine in such
2654 register access. If the data is, in fact, in memory we
2655 must always load using the size assumed to be in the
2656 register and let the insn do the different-sized
2658 || ((GET_CODE (operand) == MEM
2659 || (GET_CODE (operand)== REG
2660 && REGNO (operand) >= FIRST_PSEUDO_REGISTER))
2661 && (((GET_MODE_BITSIZE (GET_MODE (operand))
2662 < BIGGEST_ALIGNMENT)
2663 && (GET_MODE_SIZE (operand_mode[i])
2664 > GET_MODE_SIZE (GET_MODE (operand))))
2665 || (GET_CODE (operand) == MEM && BYTES_BIG_ENDIAN)
2666 #ifdef LOAD_EXTEND_OP
2667 || (GET_MODE_SIZE (operand_mode[i]) <= UNITS_PER_WORD
2668 && (GET_MODE_SIZE (GET_MODE (operand))
2670 && (GET_MODE_SIZE (operand_mode[i])
2671 > GET_MODE_SIZE (GET_MODE (operand)))
2672 && INTEGRAL_MODE_P (GET_MODE (operand))
2673 && LOAD_EXTEND_OP (GET_MODE (operand)) != NIL)
2676 /* Subreg of a hard reg which can't handle the subreg's mode
2677 or which would handle that mode in the wrong number of
2678 registers for subregging to work. */
2679 || (GET_CODE (operand) == REG
2680 && REGNO (operand) < FIRST_PSEUDO_REGISTER
2681 && ((GET_MODE_SIZE (operand_mode[i]) <= UNITS_PER_WORD
2682 && (GET_MODE_SIZE (GET_MODE (operand))
2684 && ((GET_MODE_SIZE (GET_MODE (operand))
2686 != HARD_REGNO_NREGS (REGNO (operand),
2687 GET_MODE (operand))))
2688 || ! HARD_REGNO_MODE_OK (REGNO (operand) + offset,
2693 this_alternative[i] = (int) NO_REGS;
2694 this_alternative_win[i] = 0;
2695 this_alternative_offmemok[i] = 0;
2696 this_alternative_earlyclobber[i] = 0;
2697 this_alternative_matches[i] = -1;
2699 /* An empty constraint or empty alternative
2700 allows anything which matched the pattern. */
2701 if (*p == 0 || *p == ',')
2704 /* Scan this alternative's specs for this operand;
2705 set WIN if the operand fits any letter in this alternative.
2706 Otherwise, clear BADOP if this operand could
2707 fit some letter after reloads,
2708 or set WINREG if this operand could fit after reloads
2709 provided the constraint allows some registers. */
2711 while (*p && (c = *p++) != ',')
2720 /* The last operand should not be marked commutative. */
2721 if (i != noperands - 1)
2734 /* Ignore rest of this alternative as far as
2735 reloading is concerned. */
2736 while (*p && *p != ',') p++;
2745 this_alternative_matches[i] = c;
2746 /* We are supposed to match a previous operand.
2747 If we do, we win if that one did.
2748 If we do not, count both of the operands as losers.
2749 (This is too conservative, since most of the time
2750 only a single reload insn will be needed to make
2751 the two operands win. As a result, this alternative
2752 may be rejected when it is actually desirable.) */
2753 if ((swapped && (c != commutative || i != commutative + 1))
2754 /* If we are matching as if two operands were swapped,
2755 also pretend that operands_match had been computed
2757 But if I is the second of those and C is the first,
2758 don't exchange them, because operands_match is valid
2759 only on one side of its diagonal. */
2761 [(c == commutative || c == commutative + 1)
2762 ? 2*commutative + 1 - c : c]
2763 [(i == commutative || i == commutative + 1)
2764 ? 2*commutative + 1 - i : i])
2765 : operands_match[c][i])
2766 win = this_alternative_win[c];
2769 /* Operands don't match. */
2771 /* Retroactively mark the operand we had to match
2772 as a loser, if it wasn't already. */
2773 if (this_alternative_win[c])
2775 this_alternative_win[c] = 0;
2776 if (this_alternative[c] == (int) NO_REGS)
2778 /* But count the pair only once in the total badness of
2779 this alternative, if the pair can be a dummy reload. */
2781 = find_dummy_reload (recog_operand[i], recog_operand[c],
2782 recog_operand_loc[i], recog_operand_loc[c],
2783 operand_mode[i], operand_mode[c],
2784 this_alternative[c], -1);
2789 /* This can be fixed with reloads if the operand
2790 we are supposed to match can be fixed with reloads. */
2792 this_alternative[i] = this_alternative[c];
2794 /* If we have to reload this operand and some previous
2795 operand also had to match the same thing as this
2796 operand, we don't know how to do that. So reject this
2798 if (! win || force_reload)
2799 for (j = 0; j < i; j++)
2800 if (this_alternative_matches[j]
2801 == this_alternative_matches[i])
2807 /* All necessary reloads for an address_operand
2808 were handled in find_reloads_address. */
2809 this_alternative[i] = (int) BASE_REG_CLASS;
2816 if (GET_CODE (operand) == MEM
2817 || (GET_CODE (operand) == REG
2818 && REGNO (operand) >= FIRST_PSEUDO_REGISTER
2819 && reg_renumber[REGNO (operand)] < 0))
2821 if (CONSTANT_P (operand))
2827 if (GET_CODE (operand) == MEM
2828 && ! address_reloaded[i]
2829 && (GET_CODE (XEXP (operand, 0)) == PRE_DEC
2830 || GET_CODE (XEXP (operand, 0)) == POST_DEC))
2835 if (GET_CODE (operand) == MEM
2836 && ! address_reloaded[i]
2837 && (GET_CODE (XEXP (operand, 0)) == PRE_INC
2838 || GET_CODE (XEXP (operand, 0)) == POST_INC))
2842 /* Memory operand whose address is not offsettable. */
2846 if (GET_CODE (operand) == MEM
2847 && ! (ind_levels ? offsettable_memref_p (operand)
2848 : offsettable_nonstrict_memref_p (operand))
2849 /* Certain mem addresses will become offsettable
2850 after they themselves are reloaded. This is important;
2851 we don't want our own handling of unoffsettables
2852 to override the handling of reg_equiv_address. */
2853 && !(GET_CODE (XEXP (operand, 0)) == REG
2855 || reg_equiv_address[REGNO (XEXP (operand, 0))] != 0)))
2859 /* Memory operand whose address is offsettable. */
2863 if ((GET_CODE (operand) == MEM
2864 /* If IND_LEVELS, find_reloads_address won't reload a
2865 pseudo that didn't get a hard reg, so we have to
2866 reject that case. */
2867 && (ind_levels ? offsettable_memref_p (operand)
2868 : offsettable_nonstrict_memref_p (operand)))
2869 /* A reloaded auto-increment address is offsettable,
2870 because it is now just a simple register indirect. */
2871 || (GET_CODE (operand) == MEM
2872 && address_reloaded[i]
2873 && (GET_CODE (XEXP (operand, 0)) == PRE_INC
2874 || GET_CODE (XEXP (operand, 0)) == PRE_DEC
2875 || GET_CODE (XEXP (operand, 0)) == POST_INC
2876 || GET_CODE (XEXP (operand, 0)) == POST_DEC))
2877 /* Certain mem addresses will become offsettable
2878 after they themselves are reloaded. This is important;
2879 we don't want our own handling of unoffsettables
2880 to override the handling of reg_equiv_address. */
2881 || (GET_CODE (operand) == MEM
2882 && GET_CODE (XEXP (operand, 0)) == REG
2884 || reg_equiv_address[REGNO (XEXP (operand, 0))] != 0))
2885 || (GET_CODE (operand) == REG
2886 && REGNO (operand) >= FIRST_PSEUDO_REGISTER
2887 && reg_renumber[REGNO (operand)] < 0
2888 /* If reg_equiv_address is nonzero, we will be
2889 loading it into a register; hence it will be
2890 offsettable, but we cannot say that reg_equiv_mem
2891 is offsettable without checking. */
2892 && ((reg_equiv_mem[REGNO (operand)] != 0
2893 && offsettable_memref_p (reg_equiv_mem[REGNO (operand)]))
2894 || (reg_equiv_address[REGNO (operand)] != 0))))
2896 if (CONSTANT_P (operand) || GET_CODE (operand) == MEM)
2903 /* Output operand that is stored before the need for the
2904 input operands (and their index registers) is over. */
2905 earlyclobber = 1, this_earlyclobber = 1;
2909 #ifndef REAL_ARITHMETIC
2910 /* Match any floating double constant, but only if
2911 we can examine the bits of it reliably. */
2912 if ((HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
2913 || HOST_BITS_PER_WIDE_INT != BITS_PER_WORD)
2914 && GET_MODE (operand) != VOIDmode && ! flag_pretend_float)
2917 if (GET_CODE (operand) == CONST_DOUBLE)
2922 if (GET_CODE (operand) == CONST_DOUBLE)
2928 if (GET_CODE (operand) == CONST_DOUBLE
2929 && CONST_DOUBLE_OK_FOR_LETTER_P (operand, c))
2934 if (GET_CODE (operand) == CONST_INT
2935 || (GET_CODE (operand) == CONST_DOUBLE
2936 && GET_MODE (operand) == VOIDmode))
2939 if (CONSTANT_P (operand)
2940 #ifdef LEGITIMATE_PIC_OPERAND_P
2941 && (! flag_pic || LEGITIMATE_PIC_OPERAND_P (operand))
2948 if (GET_CODE (operand) == CONST_INT
2949 || (GET_CODE (operand) == CONST_DOUBLE
2950 && GET_MODE (operand) == VOIDmode))
2962 if (GET_CODE (operand) == CONST_INT
2963 && CONST_OK_FOR_LETTER_P (INTVAL (operand), c))
2973 /* A PLUS is never a valid operand, but reload can make
2974 it from a register when eliminating registers. */
2975 && GET_CODE (operand) != PLUS
2976 /* A SCRATCH is not a valid operand. */
2977 && GET_CODE (operand) != SCRATCH
2978 #ifdef LEGITIMATE_PIC_OPERAND_P
2979 && (! CONSTANT_P (operand)
2981 || LEGITIMATE_PIC_OPERAND_P (operand))
2983 && (GENERAL_REGS == ALL_REGS
2984 || GET_CODE (operand) != REG
2985 || (REGNO (operand) >= FIRST_PSEUDO_REGISTER
2986 && reg_renumber[REGNO (operand)] < 0)))
2988 /* Drop through into 'r' case */
2992 = (int) reg_class_subunion[this_alternative[i]][(int) GENERAL_REGS];
2995 #ifdef EXTRA_CONSTRAINT
3001 if (EXTRA_CONSTRAINT (operand, c))
3008 = (int) reg_class_subunion[this_alternative[i]][(int) REG_CLASS_FROM_LETTER (c)];
3011 if (GET_MODE (operand) == BLKmode)
3014 if (GET_CODE (operand) == REG
3015 && reg_fits_class_p (operand, this_alternative[i],
3016 offset, GET_MODE (recog_operand[i])))
3023 /* If this operand could be handled with a reg,
3024 and some reg is allowed, then this operand can be handled. */
3025 if (winreg && this_alternative[i] != (int) NO_REGS)
3028 /* Record which operands fit this alternative. */
3029 this_alternative_earlyclobber[i] = earlyclobber;
3030 if (win && ! force_reload)
3031 this_alternative_win[i] = 1;
3034 int const_to_mem = 0;
3036 this_alternative_offmemok[i] = offmemok;
3040 /* Alternative loses if it has no regs for a reg operand. */
3041 if (GET_CODE (operand) == REG
3042 && this_alternative[i] == (int) NO_REGS
3043 && this_alternative_matches[i] < 0)
3046 /* Alternative loses if it requires a type of reload not
3047 permitted for this insn. We can always reload SCRATCH
3048 and objects with a REG_UNUSED note. */
3049 if (GET_CODE (operand) != SCRATCH
3050 && modified[i] != RELOAD_READ && no_output_reloads
3051 && ! find_reg_note (insn, REG_UNUSED, operand))
3053 else if (modified[i] != RELOAD_WRITE && no_input_reloads)
3056 /* If this is a constant that is reloaded into the desired
3057 class by copying it to memory first, count that as another
3058 reload. This is consistent with other code and is
3059 required to avoid choosing another alternative when
3060 the constant is moved into memory by this function on
3061 an early reload pass. Note that the test here is
3062 precisely the same as in the code below that calls
3064 if (CONSTANT_P (operand)
3065 /* force_const_mem does not accept HIGH. */
3066 && GET_CODE (operand) != HIGH
3067 && (PREFERRED_RELOAD_CLASS (operand,
3068 (enum reg_class) this_alternative[i])
3070 && operand_mode[i] != VOIDmode)
3073 if (this_alternative[i] != (int) NO_REGS)
3077 /* If we can't reload this value at all, reject this
3078 alternative. Note that we could also lose due to
3079 LIMIT_RELOAD_RELOAD_CLASS, but we don't check that
3082 if (! CONSTANT_P (operand)
3083 && (enum reg_class) this_alternative[i] != NO_REGS
3084 && (PREFERRED_RELOAD_CLASS (operand,
3085 (enum reg_class) this_alternative[i])
3089 /* We prefer to reload pseudos over reloading other things,
3090 since such reloads may be able to be eliminated later.
3091 If we are reloading a SCRATCH, we won't be generating any
3092 insns, just using a register, so it is also preferred.
3093 So bump REJECT in other cases. Don't do this in the
3094 case where we are forcing a constant into memory and
3095 it will then win since we don't want to have a different
3096 alternative match then. */
3097 if (! (GET_CODE (operand) == REG
3098 && REGNO (operand) >= FIRST_PSEUDO_REGISTER)
3099 && GET_CODE (operand) != SCRATCH
3100 && ! (const_to_mem && constmemok))
3104 /* If this operand is a pseudo register that didn't get a hard
3105 reg and this alternative accepts some register, see if the
3106 class that we want is a subset of the preferred class for this
3107 register. If not, but it intersects that class, use the
3108 preferred class instead. If it does not intersect the preferred
3109 class, show that usage of this alternative should be discouraged;
3110 it will be discouraged more still if the register is `preferred
3111 or nothing'. We do this because it increases the chance of
3112 reusing our spill register in a later insn and avoiding a pair
3113 of memory stores and loads.
3115 Don't bother with this if this alternative will accept this
3118 Don't do this for a multiword operand, since it is only a
3119 small win and has the risk of requiring more spill registers,
3120 which could cause a large loss.
3122 Don't do this if the preferred class has only one register
3123 because we might otherwise exhaust the class. */
3126 if (! win && this_alternative[i] != (int) NO_REGS
3127 && GET_MODE_SIZE (operand_mode[i]) <= UNITS_PER_WORD
3128 && reg_class_size[(int) preferred_class[i]] > 1)
3130 if (! reg_class_subset_p (this_alternative[i],
3131 preferred_class[i]))
3133 /* Since we don't have a way of forming the intersection,
3134 we just do something special if the preferred class
3135 is a subset of the class we have; that's the most
3136 common case anyway. */
3137 if (reg_class_subset_p (preferred_class[i],
3138 this_alternative[i]))
3139 this_alternative[i] = (int) preferred_class[i];
3141 reject += (1 + pref_or_nothing[i]);
3146 /* Now see if any output operands that are marked "earlyclobber"
3147 in this alternative conflict with any input operands
3148 or any memory addresses. */
3150 for (i = 0; i < noperands; i++)
3151 if (this_alternative_earlyclobber[i]
3152 && this_alternative_win[i])
3154 struct decomposition early_data;
3156 early_data = decompose (recog_operand[i]);
3158 if (modified[i] == RELOAD_READ)
3160 if (this_insn_is_asm)
3161 warning_for_asm (this_insn,
3162 "`&' constraint used with input operand");
3168 if (this_alternative[i] == NO_REGS)
3170 this_alternative_earlyclobber[i] = 0;
3171 if (this_insn_is_asm)
3172 error_for_asm (this_insn,
3173 "`&' constraint used with no register class");
3178 for (j = 0; j < noperands; j++)
3179 /* Is this an input operand or a memory ref? */
3180 if ((GET_CODE (recog_operand[j]) == MEM
3181 || modified[j] != RELOAD_WRITE)
3183 /* Ignore things like match_operator operands. */
3184 && *constraints1[j] != 0
3185 /* Don't count an input operand that is constrained to match
3186 the early clobber operand. */
3187 && ! (this_alternative_matches[j] == i
3188 && rtx_equal_p (recog_operand[i], recog_operand[j]))
3189 /* Is it altered by storing the earlyclobber operand? */
3190 && !immune_p (recog_operand[j], recog_operand[i], early_data))
3192 /* If the output is in a single-reg class,
3193 it's costly to reload it, so reload the input instead. */
3194 if (reg_class_size[this_alternative[i]] == 1
3195 && (GET_CODE (recog_operand[j]) == REG
3196 || GET_CODE (recog_operand[j]) == SUBREG))
3199 this_alternative_win[j] = 0;
3204 /* If an earlyclobber operand conflicts with something,
3205 it must be reloaded, so request this and count the cost. */
3209 this_alternative_win[i] = 0;
3210 for (j = 0; j < noperands; j++)
3211 if (this_alternative_matches[j] == i
3212 && this_alternative_win[j])
3214 this_alternative_win[j] = 0;
3220 /* If one alternative accepts all the operands, no reload required,
3221 choose that alternative; don't consider the remaining ones. */
3224 /* Unswap these so that they are never swapped at `finish'. */
3225 if (commutative >= 0)
3227 recog_operand[commutative] = substed_operand[commutative];
3228 recog_operand[commutative + 1]
3229 = substed_operand[commutative + 1];
3231 for (i = 0; i < noperands; i++)
3233 goal_alternative_win[i] = 1;
3234 goal_alternative[i] = this_alternative[i];
3235 goal_alternative_offmemok[i] = this_alternative_offmemok[i];
3236 goal_alternative_matches[i] = this_alternative_matches[i];
3237 goal_alternative_earlyclobber[i]
3238 = this_alternative_earlyclobber[i];
3240 goal_alternative_number = this_alternative_number;
3241 goal_alternative_swapped = swapped;
3242 goal_earlyclobber = this_earlyclobber;
3246 /* REJECT, set by the ! and ? constraint characters and when a register
3247 would be reloaded into a non-preferred class, discourages the use of
3248 this alternative for a reload goal. REJECT is incremented by three
3249 for each ? and one for each non-preferred class. */
3250 losers = losers * 3 + reject;
3252 /* If this alternative can be made to work by reloading,
3253 and it needs less reloading than the others checked so far,
3254 record it as the chosen goal for reloading. */
3255 if (! bad && best > losers)
3257 for (i = 0; i < noperands; i++)
3259 goal_alternative[i] = this_alternative[i];
3260 goal_alternative_win[i] = this_alternative_win[i];
3261 goal_alternative_offmemok[i] = this_alternative_offmemok[i];
3262 goal_alternative_matches[i] = this_alternative_matches[i];
3263 goal_alternative_earlyclobber[i]
3264 = this_alternative_earlyclobber[i];
3266 goal_alternative_swapped = swapped;
3268 goal_alternative_number = this_alternative_number;
3269 goal_earlyclobber = this_earlyclobber;
3273 /* If insn is commutative (it's safe to exchange a certain pair of operands)
3274 then we need to try each alternative twice,
3275 the second time matching those two operands
3276 as if we had exchanged them.
3277 To do this, really exchange them in operands.
3279 If we have just tried the alternatives the second time,
3280 return operands to normal and drop through. */
3282 if (commutative >= 0)
3287 register enum reg_class tclass;
3290 recog_operand[commutative] = substed_operand[commutative + 1];
3291 recog_operand[commutative + 1] = substed_operand[commutative];
3293 tclass = preferred_class[commutative];
3294 preferred_class[commutative] = preferred_class[commutative + 1];
3295 preferred_class[commutative + 1] = tclass;
3297 t = pref_or_nothing[commutative];
3298 pref_or_nothing[commutative] = pref_or_nothing[commutative + 1];
3299 pref_or_nothing[commutative + 1] = t;
3301 bcopy ((char *) constraints1, (char *) constraints,
3302 noperands * sizeof (char *));
3307 recog_operand[commutative] = substed_operand[commutative];
3308 recog_operand[commutative + 1] = substed_operand[commutative + 1];
3312 /* The operands don't meet the constraints.
3313 goal_alternative describes the alternative
3314 that we could reach by reloading the fewest operands.
3315 Reload so as to fit it. */
3317 if (best == MAX_RECOG_OPERANDS + 300)
3319 /* No alternative works with reloads?? */
3320 if (insn_code_number >= 0)
3322 error_for_asm (insn, "inconsistent operand constraints in an `asm'");
3323 /* Avoid further trouble with this insn. */
3324 PATTERN (insn) = gen_rtx (USE, VOIDmode, const0_rtx);
3329 /* Jump to `finish' from above if all operands are valid already.
3330 In that case, goal_alternative_win is all 1. */
3333 /* Right now, for any pair of operands I and J that are required to match,
3335 goal_alternative_matches[J] is I.
3336 Set up goal_alternative_matched as the inverse function:
3337 goal_alternative_matched[I] = J. */
3339 for (i = 0; i < noperands; i++)
3340 goal_alternative_matched[i] = -1;
3342 for (i = 0; i < noperands; i++)
3343 if (! goal_alternative_win[i]
3344 && goal_alternative_matches[i] >= 0)
3345 goal_alternative_matched[goal_alternative_matches[i]] = i;
3347 /* If the best alternative is with operands 1 and 2 swapped,
3348 consider them swapped before reporting the reloads. Update the
3349 operand numbers of any reloads already pushed. */
3351 if (goal_alternative_swapped)
3355 tem = substed_operand[commutative];
3356 substed_operand[commutative] = substed_operand[commutative + 1];
3357 substed_operand[commutative + 1] = tem;
3358 tem = recog_operand[commutative];
3359 recog_operand[commutative] = recog_operand[commutative + 1];
3360 recog_operand[commutative + 1] = tem;
3362 for (i = 0; i < n_reloads; i++)
3364 if (reload_opnum[i] == commutative)
3365 reload_opnum[i] = commutative + 1;
3366 else if (reload_opnum[i] == commutative + 1)
3367 reload_opnum[i] = commutative;
3371 /* Perform whatever substitutions on the operands we are supposed
3372 to make due to commutativity or replacement of registers
3373 with equivalent constants or memory slots. */
3375 for (i = 0; i < noperands; i++)
3377 *recog_operand_loc[i] = substed_operand[i];
3378 /* While we are looping on operands, initialize this. */
3379 operand_reloadnum[i] = -1;
3381 /* If this is an earlyclobber operand, we need to widen the scope.
3382 The reload must remain valid from the start of the insn being
3383 reloaded until after the operand is stored into its destination.
3384 We approximate this with RELOAD_OTHER even though we know that we
3385 do not conflict with RELOAD_FOR_INPUT_ADDRESS reloads.
3387 One special case that is worth checking is when we have an
3388 output that is earlyclobber but isn't used past the insn (typically
3389 a SCRATCH). In this case, we only need have the reload live
3390 through the insn itself, but not for any of our input or output
3393 In any case, anything needed to address this operand can remain
3394 however they were previously categorized. */
3396 if (goal_alternative_earlyclobber[i])
3398 = (find_reg_note (insn, REG_UNUSED, recog_operand[i])
3399 ? RELOAD_FOR_INSN : RELOAD_OTHER);
3402 /* Any constants that aren't allowed and can't be reloaded
3403 into registers are here changed into memory references. */
3404 for (i = 0; i < noperands; i++)
3405 if (! goal_alternative_win[i]
3406 && CONSTANT_P (recog_operand[i])
3407 /* force_const_mem does not accept HIGH. */
3408 && GET_CODE (recog_operand[i]) != HIGH
3409 && (PREFERRED_RELOAD_CLASS (recog_operand[i],
3410 (enum reg_class) goal_alternative[i])
3412 && operand_mode[i] != VOIDmode)
3414 *recog_operand_loc[i] = recog_operand[i]
3415 = find_reloads_toplev (force_const_mem (operand_mode[i],
3417 i, address_type[i], ind_levels, 0);
3418 if (alternative_allows_memconst (constraints1[i],
3419 goal_alternative_number))
3420 goal_alternative_win[i] = 1;
3423 /* Record the values of the earlyclobber operands for the caller. */
3424 if (goal_earlyclobber)
3425 for (i = 0; i < noperands; i++)
3426 if (goal_alternative_earlyclobber[i])
3427 reload_earlyclobbers[n_earlyclobbers++] = recog_operand[i];
3429 /* Now record reloads for all the operands that need them. */
3430 for (i = 0; i < noperands; i++)
3431 if (! goal_alternative_win[i])
3433 /* Operands that match previous ones have already been handled. */
3434 if (goal_alternative_matches[i] >= 0)
3436 /* Handle an operand with a nonoffsettable address
3437 appearing where an offsettable address will do
3438 by reloading the address into a base register.
3440 ??? We can also do this when the operand is a register and
3441 reg_equiv_mem is not offsettable, but this is a bit tricky,
3442 so we don't bother with it. It may not be worth doing. */
3443 else if (goal_alternative_matched[i] == -1
3444 && goal_alternative_offmemok[i]
3445 && GET_CODE (recog_operand[i]) == MEM)
3447 operand_reloadnum[i]
3448 = push_reload (XEXP (recog_operand[i], 0), NULL_RTX,
3449 &XEXP (recog_operand[i], 0), NULL_PTR,
3450 BASE_REG_CLASS, GET_MODE (XEXP (recog_operand[i], 0)),
3451 VOIDmode, 0, 0, i, RELOAD_FOR_INPUT);
3452 reload_inc[operand_reloadnum[i]]
3453 = GET_MODE_SIZE (GET_MODE (recog_operand[i]));
3455 /* If this operand is an output, we will have made any
3456 reloads for its address as RELOAD_FOR_OUTPUT_ADDRESS, but
3457 now we are treating part of the operand as an input, so
3458 we must change these to RELOAD_FOR_INPUT_ADDRESS. */
3460 if (modified[i] == RELOAD_WRITE)
3461 for (j = 0; j < n_reloads; j++)
3462 if (reload_opnum[j] == i
3463 && reload_when_needed[j] == RELOAD_FOR_OUTPUT_ADDRESS)
3464 reload_when_needed[j] = RELOAD_FOR_INPUT_ADDRESS;
3466 else if (goal_alternative_matched[i] == -1)
3467 operand_reloadnum[i] =
3468 push_reload (modified[i] != RELOAD_WRITE ? recog_operand[i] : 0,
3469 modified[i] != RELOAD_READ ? recog_operand[i] : 0,
3470 (modified[i] != RELOAD_WRITE ?
3471 recog_operand_loc[i] : 0),
3472 modified[i] != RELOAD_READ ? recog_operand_loc[i] : 0,
3473 (enum reg_class) goal_alternative[i],
3474 (modified[i] == RELOAD_WRITE
3475 ? VOIDmode : operand_mode[i]),
3476 (modified[i] == RELOAD_READ
3477 ? VOIDmode : operand_mode[i]),
3478 (insn_code_number < 0 ? 0
3479 : insn_operand_strict_low[insn_code_number][i]),
3480 0, i, operand_type[i]);
3481 /* In a matching pair of operands, one must be input only
3482 and the other must be output only.
3483 Pass the input operand as IN and the other as OUT. */
3484 else if (modified[i] == RELOAD_READ
3485 && modified[goal_alternative_matched[i]] == RELOAD_WRITE)
3487 operand_reloadnum[i]
3488 = push_reload (recog_operand[i],
3489 recog_operand[goal_alternative_matched[i]],
3490 recog_operand_loc[i],
3491 recog_operand_loc[goal_alternative_matched[i]],
3492 (enum reg_class) goal_alternative[i],
3494 operand_mode[goal_alternative_matched[i]],
3495 0, 0, i, RELOAD_OTHER);
3496 operand_reloadnum[goal_alternative_matched[i]] = output_reloadnum;
3498 else if (modified[i] == RELOAD_WRITE
3499 && modified[goal_alternative_matched[i]] == RELOAD_READ)
3501 operand_reloadnum[goal_alternative_matched[i]]
3502 = push_reload (recog_operand[goal_alternative_matched[i]],
3504 recog_operand_loc[goal_alternative_matched[i]],
3505 recog_operand_loc[i],
3506 (enum reg_class) goal_alternative[i],
3507 operand_mode[goal_alternative_matched[i]],
3509 0, 0, i, RELOAD_OTHER);
3510 operand_reloadnum[i] = output_reloadnum;
3512 else if (insn_code_number >= 0)
3516 error_for_asm (insn, "inconsistent operand constraints in an `asm'");
3517 /* Avoid further trouble with this insn. */
3518 PATTERN (insn) = gen_rtx (USE, VOIDmode, const0_rtx);
3523 else if (goal_alternative_matched[i] < 0
3524 && goal_alternative_matches[i] < 0
3527 /* For each non-matching operand that's a MEM or a pseudo-register
3528 that didn't get a hard register, make an optional reload.
3529 This may get done even if the insn needs no reloads otherwise. */
3531 rtx operand = recog_operand[i];
3533 while (GET_CODE (operand) == SUBREG)
3534 operand = XEXP (operand, 0);
3535 if ((GET_CODE (operand) == MEM
3536 || (GET_CODE (operand) == REG
3537 && REGNO (operand) >= FIRST_PSEUDO_REGISTER))
3538 && (enum reg_class) goal_alternative[i] != NO_REGS
3539 && ! no_input_reloads
3540 /* Optional output reloads don't do anything and we mustn't
3541 make in-out reloads on insns that are not permitted output
3543 && (modified[i] == RELOAD_READ
3544 || (modified[i] == RELOAD_READ_WRITE && ! no_output_reloads)))
3545 operand_reloadnum[i]
3546 = push_reload (modified[i] != RELOAD_WRITE ? recog_operand[i] : 0,
3547 modified[i] != RELOAD_READ ? recog_operand[i] : 0,
3548 (modified[i] != RELOAD_WRITE
3549 ? recog_operand_loc[i] : 0),
3550 (modified[i] != RELOAD_READ
3551 ? recog_operand_loc[i] : 0),
3552 (enum reg_class) goal_alternative[i],
3553 (modified[i] == RELOAD_WRITE
3554 ? VOIDmode : operand_mode[i]),
3555 (modified[i] == RELOAD_READ
3556 ? VOIDmode : operand_mode[i]),
3557 (insn_code_number < 0 ? 0
3558 : insn_operand_strict_low[insn_code_number][i]),
3559 1, i, operand_type[i]);
3561 else if (goal_alternative_matches[i] >= 0
3562 && goal_alternative_win[goal_alternative_matches[i]]
3563 && modified[i] == RELOAD_READ
3564 && modified[goal_alternative_matches[i]] == RELOAD_WRITE
3565 && ! no_input_reloads && ! no_output_reloads
3568 /* Similarly, make an optional reload for a pair of matching
3569 objects that are in MEM or a pseudo that didn't get a hard reg. */
3571 rtx operand = recog_operand[i];
3573 while (GET_CODE (operand) == SUBREG)
3574 operand = XEXP (operand, 0);
3575 if ((GET_CODE (operand) == MEM
3576 || (GET_CODE (operand) == REG
3577 && REGNO (operand) >= FIRST_PSEUDO_REGISTER))
3578 && ((enum reg_class) goal_alternative[goal_alternative_matches[i]]
3580 operand_reloadnum[i] = operand_reloadnum[goal_alternative_matches[i]]
3581 = push_reload (recog_operand[goal_alternative_matches[i]],
3583 recog_operand_loc[goal_alternative_matches[i]],
3584 recog_operand_loc[i],
3585 (enum reg_class) goal_alternative[goal_alternative_matches[i]],
3586 operand_mode[goal_alternative_matches[i]],
3588 0, 1, goal_alternative_matches[i], RELOAD_OTHER);
3591 /* If this insn pattern contains any MATCH_DUP's, make sure that
3592 they will be substituted if the operands they match are substituted.
3593 Also do now any substitutions we already did on the operands.
3595 Don't do this if we aren't making replacements because we might be
3596 propagating things allocated by frame pointer elimination into places
3597 it doesn't expect. */
3599 if (insn_code_number >= 0 && replace)
3600 for (i = insn_n_dups[insn_code_number] - 1; i >= 0; i--)
3602 int opno = recog_dup_num[i];
3603 *recog_dup_loc[i] = *recog_operand_loc[opno];
3604 if (operand_reloadnum[opno] >= 0)
3605 push_replacement (recog_dup_loc[i], operand_reloadnum[opno],
3606 insn_operand_mode[insn_code_number][opno]);
3610 /* This loses because reloading of prior insns can invalidate the equivalence
3611 (or at least find_equiv_reg isn't smart enough to find it any more),
3612 causing this insn to need more reload regs than it needed before.
3613 It may be too late to make the reload regs available.
3614 Now this optimization is done safely in choose_reload_regs. */
3616 /* For each reload of a reg into some other class of reg,
3617 search for an existing equivalent reg (same value now) in the right class.
3618 We can use it as long as we don't need to change its contents. */
3619 for (i = 0; i < n_reloads; i++)
3620 if (reload_reg_rtx[i] == 0
3621 && reload_in[i] != 0
3622 && GET_CODE (reload_in[i]) == REG
3623 && reload_out[i] == 0)
3626 = find_equiv_reg (reload_in[i], insn, reload_reg_class[i], -1,
3627 static_reload_reg_p, 0, reload_inmode[i]);
3628 /* Prevent generation of insn to load the value
3629 because the one we found already has the value. */
3630 if (reload_reg_rtx[i])
3631 reload_in[i] = reload_reg_rtx[i];
3635 /* Perhaps an output reload can be combined with another
3636 to reduce needs by one. */
3637 if (!goal_earlyclobber)
3640 /* If we have a pair of reloads for parts of an address, they are reloading
3641 the same object, the operands themselves were not reloaded, and they
3642 are for two operands that are supposed to match, merge the reloads and
3643 change the type of the surviving reload to RELOAD_FOR_OPERAND_ADDRESS. */
3645 for (i = 0; i < n_reloads; i++)
3649 for (j = i + 1; j < n_reloads; j++)
3650 if ((reload_when_needed[i] == RELOAD_FOR_INPUT_ADDRESS
3651 || reload_when_needed[i] == RELOAD_FOR_OUTPUT_ADDRESS)
3652 && (reload_when_needed[j] == RELOAD_FOR_INPUT_ADDRESS
3653 || reload_when_needed[j] == RELOAD_FOR_OUTPUT_ADDRESS)
3654 && rtx_equal_p (reload_in[i], reload_in[j])
3655 && (operand_reloadnum[reload_opnum[i]] < 0
3656 || reload_optional[operand_reloadnum[reload_opnum[i]]])
3657 && (operand_reloadnum[reload_opnum[j]] < 0
3658 || reload_optional[operand_reloadnum[reload_opnum[j]]])
3659 && (goal_alternative_matches[reload_opnum[i]] == reload_opnum[j]
3660 || (goal_alternative_matches[reload_opnum[j]]
3661 == reload_opnum[i])))
3663 for (k = 0; k < n_replacements; k++)
3664 if (replacements[k].what == j)
3665 replacements[k].what = i;
3667 reload_when_needed[i] = RELOAD_FOR_OPERAND_ADDRESS;
3672 /* Scan all the reloads and update their type.
3673 If a reload is for the address of an operand and we didn't reload
3674 that operand, change the type. Similarly, change the operand number
3675 of a reload when two operands match. If a reload is optional, treat it
3676 as though the operand isn't reloaded.
3678 ??? This latter case is somewhat odd because if we do the optional
3679 reload, it means the object is hanging around. Thus we need only
3680 do the address reload if the optional reload was NOT done.
3682 Change secondary reloads to be the address type of their operand, not
3685 If an operand's reload is now RELOAD_OTHER, change any
3686 RELOAD_FOR_INPUT_ADDRESS reloads of that operand to
3687 RELOAD_FOR_OTHER_ADDRESS. */
3689 for (i = 0; i < n_reloads; i++)
3691 if (reload_secondary_p[i]
3692 && reload_when_needed[i] == operand_type[reload_opnum[i]])
3693 reload_when_needed[i] = address_type[reload_opnum[i]];
3695 if ((reload_when_needed[i] == RELOAD_FOR_INPUT_ADDRESS
3696 || reload_when_needed[i] == RELOAD_FOR_OUTPUT_ADDRESS)
3697 && (operand_reloadnum[reload_opnum[i]] < 0
3698 || reload_optional[operand_reloadnum[reload_opnum[i]]]))
3700 /* If we have a secondary reload to go along with this reload,
3701 change its type to RELOAD_FOR_OPADDR_ADDR. */
3703 if (reload_when_needed[i] == RELOAD_FOR_INPUT_ADDRESS
3704 && reload_secondary_in_reload[i] != -1)
3706 int secondary_in_reload = reload_secondary_in_reload[i];
3708 reload_when_needed[secondary_in_reload] =
3709 RELOAD_FOR_OPADDR_ADDR;
3711 /* If there's a tertiary reload we have to change it also. */
3712 if (secondary_in_reload > 0
3713 && reload_secondary_in_reload[secondary_in_reload] != -1)
3714 reload_when_needed[reload_secondary_in_reload[secondary_in_reload]]
3715 = RELOAD_FOR_OPADDR_ADDR;
3718 if (reload_when_needed[i] == RELOAD_FOR_OUTPUT_ADDRESS
3719 && reload_secondary_out_reload[i] != -1)
3721 int secondary_out_reload = reload_secondary_out_reload[i];
3723 reload_when_needed[secondary_out_reload] =
3724 RELOAD_FOR_OPADDR_ADDR;
3726 /* If there's a tertiary reload we have to change it also. */
3727 if (secondary_out_reload
3728 && reload_secondary_out_reload[secondary_out_reload] != -1)
3729 reload_when_needed[reload_secondary_out_reload[secondary_out_reload]]
3730 = RELOAD_FOR_OPADDR_ADDR;
3732 reload_when_needed[i] = RELOAD_FOR_OPERAND_ADDRESS;
3735 if (reload_when_needed[i] == RELOAD_FOR_INPUT_ADDRESS
3736 && operand_reloadnum[reload_opnum[i]] >= 0
3737 && (reload_when_needed[operand_reloadnum[reload_opnum[i]]]
3739 reload_when_needed[i] = RELOAD_FOR_OTHER_ADDRESS;
3741 if (goal_alternative_matches[reload_opnum[i]] >= 0)
3742 reload_opnum[i] = goal_alternative_matches[reload_opnum[i]];
3745 /* See if we have any reloads that are now allowed to be merged
3746 because we've changed when the reload is needed to
3747 RELOAD_FOR_OPERAND_ADDRESS or RELOAD_FOR_OTHER_ADDRESS. Only
3748 check for the most common cases. */
3750 for (i = 0; i < n_reloads; i++)
3751 if (reload_in[i] != 0 && reload_out[i] == 0
3752 && (reload_when_needed[i] == RELOAD_FOR_OPERAND_ADDRESS
3753 || reload_when_needed[i] == RELOAD_FOR_OTHER_ADDRESS))
3754 for (j = 0; j < n_reloads; j++)
3755 if (i != j && reload_in[j] != 0 && reload_out[j] == 0
3756 && reload_when_needed[j] == reload_when_needed[i]
3757 && MATCHES (reload_in[i], reload_in[j])
3758 && reload_reg_class[i] == reload_reg_class[j]
3759 && !reload_nocombine[i] && !reload_nocombine[j]
3760 && reload_reg_rtx[i] == reload_reg_rtx[j])
3762 reload_opnum[i] = MIN (reload_opnum[i], reload_opnum[j]);
3763 transfer_replacements (i, j);
3767 #else /* no REGISTER_CONSTRAINTS */
3769 int insn_code_number;
3770 int goal_earlyclobber = 0; /* Always 0, to make combine_reloads happen. */
3772 rtx body = PATTERN (insn);
3776 n_earlyclobbers = 0;
3777 replace_reloads = replace;
3780 /* Find what kind of insn this is. NOPERANDS gets number of operands.
3781 Store the operand values in RECOG_OPERAND and the locations
3782 of the words in the insn that point to them in RECOG_OPERAND_LOC.
3783 Return if the insn needs no reload processing. */
3785 switch (GET_CODE (body))
3796 noperands = asm_noperands (body);
3799 /* This insn is an `asm' with operands.
3800 First, find out how many operands, and allocate space. */
3802 insn_code_number = -1;
3803 /* ??? This is a bug! ???
3804 Give up and delete this insn if it has too many operands. */
3805 if (noperands > MAX_RECOG_OPERANDS)
3808 /* Now get the operand values out of the insn. */
3810 decode_asm_operands (body, recog_operand, recog_operand_loc,
3811 NULL_PTR, NULL_PTR);
3816 /* Ordinary insn: recognize it, allocate space for operands and
3817 constraints, and get them out via insn_extract. */
3819 insn_code_number = recog_memoized (insn);
3820 noperands = insn_n_operands[insn_code_number];
3821 insn_extract (insn);
3827 for (i = 0; i < noperands; i++)
3829 register RTX_CODE code = GET_CODE (recog_operand[i]);
3830 int is_set_dest = GET_CODE (body) == SET && (i == 0);
3832 if (insn_code_number >= 0)
3833 if (insn_operand_address_p[insn_code_number][i])
3834 find_reloads_address (VOIDmode, NULL_PTR,
3835 recog_operand[i], recog_operand_loc[i],
3836 i, RELOAD_FOR_INPUT, ind_levels);
3838 /* In these cases, we can't tell if the operand is an input
3839 or an output, so be conservative. In practice it won't be
3843 find_reloads_address (GET_MODE (recog_operand[i]),
3844 recog_operand_loc[i],
3845 XEXP (recog_operand[i], 0),
3846 &XEXP (recog_operand[i], 0),
3847 i, RELOAD_OTHER, ind_levels);
3849 recog_operand[i] = *recog_operand_loc[i]
3850 = find_reloads_toplev (recog_operand[i], i, RELOAD_OTHER,
3851 ind_levels, is_set_dest);
3854 register int regno = REGNO (recog_operand[i]);
3855 if (reg_equiv_constant[regno] != 0 && !is_set_dest)
3856 recog_operand[i] = *recog_operand_loc[i]
3857 = reg_equiv_constant[regno];
3858 #if 0 /* This might screw code in reload1.c to delete prior output-reload
3859 that feeds this insn. */
3860 if (reg_equiv_mem[regno] != 0)
3861 recog_operand[i] = *recog_operand_loc[i]
3862 = reg_equiv_mem[regno];
3867 /* Perhaps an output reload can be combined with another
3868 to reduce needs by one. */
3869 if (!goal_earlyclobber)
3871 #endif /* no REGISTER_CONSTRAINTS */
3874 /* Return 1 if alternative number ALTNUM in constraint-string CONSTRAINT
3875 accepts a memory operand with constant address. */
3878 alternative_allows_memconst (constraint, altnum)
3883 /* Skip alternatives before the one requested. */
3886 while (*constraint++ != ',');
3889 /* Scan the requested alternative for 'm' or 'o'.
3890 If one of them is present, this alternative accepts memory constants. */
3891 while ((c = *constraint++) && c != ',' && c != '#')
3892 if (c == 'm' || c == 'o')
3897 /* Scan X for memory references and scan the addresses for reloading.
3898 Also checks for references to "constant" regs that we want to eliminate
3899 and replaces them with the values they stand for.
3900 We may alter X destructively if it contains a reference to such.
3901 If X is just a constant reg, we return the equivalent value
3904 IND_LEVELS says how many levels of indirect addressing this machine
3907 OPNUM and TYPE identify the purpose of the reload.
3909 IS_SET_DEST is true if X is the destination of a SET, which is not
3910 appropriate to be replaced by a constant. */
3913 find_reloads_toplev (x, opnum, type, ind_levels, is_set_dest)
3916 enum reload_type type;
3920 register RTX_CODE code = GET_CODE (x);
3922 register char *fmt = GET_RTX_FORMAT (code);
3927 /* This code is duplicated for speed in find_reloads. */
3928 register int regno = REGNO (x);
3929 if (reg_equiv_constant[regno] != 0 && !is_set_dest)
3930 x = reg_equiv_constant[regno];
3932 /* This creates (subreg (mem...)) which would cause an unnecessary
3933 reload of the mem. */
3934 else if (reg_equiv_mem[regno] != 0)
3935 x = reg_equiv_mem[regno];
3937 else if (reg_equiv_address[regno] != 0)
3939 /* If reg_equiv_address varies, it may be shared, so copy it. */
3940 /* We must rerun eliminate_regs, in case the elimination
3941 offsets have changed. */
3942 rtx addr = XEXP (eliminate_regs (reg_equiv_memory_loc[regno], 0,
3946 if (rtx_varies_p (addr))
3947 addr = copy_rtx (addr);
3949 x = gen_rtx (MEM, GET_MODE (x), addr);
3950 RTX_UNCHANGING_P (x) = RTX_UNCHANGING_P (regno_reg_rtx[regno]);
3951 find_reloads_address (GET_MODE (x), NULL_PTR,
3953 &XEXP (x, 0), opnum, type, ind_levels);
3960 find_reloads_address (GET_MODE (x), &tem, XEXP (x, 0), &XEXP (x, 0),
3961 opnum, type, ind_levels);
3965 if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == REG)
3967 /* Check for SUBREG containing a REG that's equivalent to a constant.
3968 If the constant has a known value, truncate it right now.
3969 Similarly if we are extracting a single-word of a multi-word
3970 constant. If the constant is symbolic, allow it to be substituted
3971 normally. push_reload will strip the subreg later. If the
3972 constant is VOIDmode, abort because we will lose the mode of
3973 the register (this should never happen because one of the cases
3974 above should handle it). */
3976 register int regno = REGNO (SUBREG_REG (x));
3979 if (subreg_lowpart_p (x)
3980 && regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0
3981 && reg_equiv_constant[regno] != 0
3982 && (tem = gen_lowpart_common (GET_MODE (x),
3983 reg_equiv_constant[regno])) != 0)
3986 if (GET_MODE_BITSIZE (GET_MODE (x)) == BITS_PER_WORD
3987 && regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0
3988 && reg_equiv_constant[regno] != 0
3989 && (tem = operand_subword (reg_equiv_constant[regno],
3991 GET_MODE (SUBREG_REG (x)))) != 0)
3994 if (regno >= FIRST_PSEUDO_REGISTER && reg_renumber[regno] < 0
3995 && reg_equiv_constant[regno] != 0
3996 && GET_MODE (reg_equiv_constant[regno]) == VOIDmode)
3999 /* If the subreg contains a reg that will be converted to a mem,
4000 convert the subreg to a narrower memref now.
4001 Otherwise, we would get (subreg (mem ...) ...),
4002 which would force reload of the mem.
4004 We also need to do this if there is an equivalent MEM that is
4005 not offsettable. In that case, alter_subreg would produce an
4006 invalid address on big-endian machines.
4008 For machines that extend byte loads, we must not reload using
4009 a wider mode if we have a paradoxical SUBREG. find_reloads will
4010 force a reload in that case. So we should not do anything here. */
4012 else if (regno >= FIRST_PSEUDO_REGISTER
4013 #ifdef LOAD_EXTEND_OP
4014 && (GET_MODE_SIZE (GET_MODE (x))
4015 <= GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
4017 && (reg_equiv_address[regno] != 0
4018 || (reg_equiv_mem[regno] != 0
4019 && (! strict_memory_address_p (GET_MODE (x),
4020 XEXP (reg_equiv_mem[regno], 0))
4021 || ! offsettable_memref_p (reg_equiv_mem[regno])))))
4023 int offset = SUBREG_WORD (x) * UNITS_PER_WORD;
4024 /* We must rerun eliminate_regs, in case the elimination
4025 offsets have changed. */
4026 rtx addr = XEXP (eliminate_regs (reg_equiv_memory_loc[regno], 0,
4029 if (BYTES_BIG_ENDIAN)
4032 size = GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)));
4033 offset += MIN (size, UNITS_PER_WORD);
4034 size = GET_MODE_SIZE (GET_MODE (x));
4035 offset -= MIN (size, UNITS_PER_WORD);
4037 addr = plus_constant (addr, offset);
4038 x = gen_rtx (MEM, GET_MODE (x), addr);
4039 RTX_UNCHANGING_P (x) = RTX_UNCHANGING_P (regno_reg_rtx[regno]);
4040 find_reloads_address (GET_MODE (x), NULL_PTR,
4042 &XEXP (x, 0), opnum, type, ind_levels);
4047 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
4050 XEXP (x, i) = find_reloads_toplev (XEXP (x, i), opnum, type,
4051 ind_levels, is_set_dest);
4056 /* Return a mem ref for the memory equivalent of reg REGNO.
4057 This mem ref is not shared with anything. */
4060 make_memloc (ad, regno)
4065 /* We must rerun eliminate_regs, in case the elimination
4066 offsets have changed. */
4067 rtx tem = XEXP (eliminate_regs (reg_equiv_memory_loc[regno], 0, NULL_RTX),
4070 #if 0 /* We cannot safely reuse a memloc made here;
4071 if the pseudo appears twice, and its mem needs a reload,
4072 it gets two separate reloads assigned, but it only
4073 gets substituted with the second of them;
4074 then it can get used before that reload reg gets loaded up. */
4075 for (i = 0; i < n_memlocs; i++)
4076 if (rtx_equal_p (tem, XEXP (memlocs[i], 0)))
4080 /* If TEM might contain a pseudo, we must copy it to avoid
4081 modifying it when we do the substitution for the reload. */
4082 if (rtx_varies_p (tem))
4083 tem = copy_rtx (tem);
4085 tem = gen_rtx (MEM, GET_MODE (ad), tem);
4086 RTX_UNCHANGING_P (tem) = RTX_UNCHANGING_P (regno_reg_rtx[regno]);
4087 memlocs[n_memlocs++] = tem;
4091 /* Record all reloads needed for handling memory address AD
4092 which appears in *LOC in a memory reference to mode MODE
4093 which itself is found in location *MEMREFLOC.
4094 Note that we take shortcuts assuming that no multi-reg machine mode
4095 occurs as part of an address.
4097 OPNUM and TYPE specify the purpose of this reload.
4099 IND_LEVELS says how many levels of indirect addressing this machine
4102 Value is nonzero if this address is reloaded or replaced as a whole.
4103 This is interesting to the caller if the address is an autoincrement.
4105 Note that there is no verification that the address will be valid after
4106 this routine does its work. Instead, we rely on the fact that the address
4107 was valid when reload started. So we need only undo things that reload
4108 could have broken. These are wrong register types, pseudos not allocated
4109 to a hard register, and frame pointer elimination. */
4112 find_reloads_address (mode, memrefloc, ad, loc, opnum, type, ind_levels)
4113 enum machine_mode mode;
4118 enum reload_type type;
4124 /* If the address is a register, see if it is a legitimate address and
4125 reload if not. We first handle the cases where we need not reload
4126 or where we must reload in a non-standard way. */
4128 if (GET_CODE (ad) == REG)
4132 if (reg_equiv_constant[regno] != 0
4133 && strict_memory_address_p (mode, reg_equiv_constant[regno]))
4135 *loc = ad = reg_equiv_constant[regno];
4139 else if (reg_equiv_address[regno] != 0)
4141 tem = make_memloc (ad, regno);
4142 find_reloads_address (GET_MODE (tem), NULL_PTR, XEXP (tem, 0),
4143 &XEXP (tem, 0), opnum, type, ind_levels);
4144 push_reload (tem, NULL_RTX, loc, NULL_PTR, BASE_REG_CLASS,
4145 GET_MODE (ad), VOIDmode, 0, 0,
4150 /* We can avoid a reload if the register's equivalent memory expression
4151 is valid as an indirect memory address.
4152 But not all addresses are valid in a mem used as an indirect address:
4153 only reg or reg+constant. */
4155 else if (reg_equiv_mem[regno] != 0 && ind_levels > 0
4156 && strict_memory_address_p (mode, reg_equiv_mem[regno])
4157 && (GET_CODE (XEXP (reg_equiv_mem[regno], 0)) == REG
4158 || (GET_CODE (XEXP (reg_equiv_mem[regno], 0)) == PLUS
4159 && GET_CODE (XEXP (XEXP (reg_equiv_mem[regno], 0), 0)) == REG
4160 && CONSTANT_P (XEXP (XEXP (reg_equiv_mem[regno], 0), 1)))))
4163 /* The only remaining case where we can avoid a reload is if this is a
4164 hard register that is valid as a base register and which is not the
4165 subject of a CLOBBER in this insn. */
4167 else if (regno < FIRST_PSEUDO_REGISTER && REGNO_OK_FOR_BASE_P (regno)
4168 && ! regno_clobbered_p (regno, this_insn))
4171 /* If we do not have one of the cases above, we must do the reload. */
4172 push_reload (ad, NULL_RTX, loc, NULL_PTR, BASE_REG_CLASS,
4173 GET_MODE (ad), VOIDmode, 0, 0, opnum, type);
4177 if (strict_memory_address_p (mode, ad))
4179 /* The address appears valid, so reloads are not needed.
4180 But the address may contain an eliminable register.
4181 This can happen because a machine with indirect addressing
4182 may consider a pseudo register by itself a valid address even when
4183 it has failed to get a hard reg.
4184 So do a tree-walk to find and eliminate all such regs. */
4186 /* But first quickly dispose of a common case. */
4187 if (GET_CODE (ad) == PLUS
4188 && GET_CODE (XEXP (ad, 1)) == CONST_INT
4189 && GET_CODE (XEXP (ad, 0)) == REG
4190 && reg_equiv_constant[REGNO (XEXP (ad, 0))] == 0)
4193 subst_reg_equivs_changed = 0;
4194 *loc = subst_reg_equivs (ad);
4196 if (! subst_reg_equivs_changed)
4199 /* Check result for validity after substitution. */
4200 if (strict_memory_address_p (mode, ad))
4204 /* The address is not valid. We have to figure out why. One possibility
4205 is that it is itself a MEM. This can happen when the frame pointer is
4206 being eliminated, a pseudo is not allocated to a hard register, and the
4207 offset between the frame and stack pointers is not its initial value.
4208 In that case the pseudo will have been replaced by a MEM referring to
4209 the stack pointer. */
4210 if (GET_CODE (ad) == MEM)
4212 /* First ensure that the address in this MEM is valid. Then, unless
4213 indirect addresses are valid, reload the MEM into a register. */
4215 find_reloads_address (GET_MODE (ad), &tem, XEXP (ad, 0), &XEXP (ad, 0),
4216 opnum, type, ind_levels == 0 ? 0 : ind_levels - 1);
4218 /* If tem was changed, then we must create a new memory reference to
4219 hold it and store it back into memrefloc. */
4220 if (tem != ad && memrefloc)
4222 *memrefloc = copy_rtx (*memrefloc);
4223 copy_replacements (tem, XEXP (*memrefloc, 0));
4224 loc = &XEXP (*memrefloc, 0);
4227 /* Check similar cases as for indirect addresses as above except
4228 that we can allow pseudos and a MEM since they should have been
4229 taken care of above. */
4232 || (GET_CODE (XEXP (tem, 0)) == SYMBOL_REF && ! indirect_symref_ok)
4233 || GET_CODE (XEXP (tem, 0)) == MEM
4234 || ! (GET_CODE (XEXP (tem, 0)) == REG
4235 || (GET_CODE (XEXP (tem, 0)) == PLUS
4236 && GET_CODE (XEXP (XEXP (tem, 0), 0)) == REG
4237 && GET_CODE (XEXP (XEXP (tem, 0), 1)) == CONST_INT)))
4239 /* Must use TEM here, not AD, since it is the one that will
4240 have any subexpressions reloaded, if needed. */
4241 push_reload (tem, NULL_RTX, loc, NULL_PTR,
4242 BASE_REG_CLASS, GET_MODE (tem), VOIDmode, 0,
4250 /* If we have address of a stack slot but it's not valid because the
4251 displacement is too large, compute the sum in a register.
4252 Handle all base registers here, not just fp/ap/sp, because on some
4253 targets (namely SH) we can also get too large displacements from
4254 big-endian corrections. */
4255 else if (GET_CODE (ad) == PLUS
4256 && GET_CODE (XEXP (ad, 0)) == REG
4257 && REGNO (XEXP (ad, 0)) < FIRST_PSEUDO_REGISTER
4258 && REG_OK_FOR_BASE_P (XEXP (ad, 0))
4259 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
4261 /* Unshare the MEM rtx so we can safely alter it. */
4264 *memrefloc = copy_rtx (*memrefloc);
4265 loc = &XEXP (*memrefloc, 0);
4267 if (double_reg_address_ok)
4269 /* Unshare the sum as well. */
4270 *loc = ad = copy_rtx (ad);
4271 /* Reload the displacement into an index reg.
4272 We assume the frame pointer or arg pointer is a base reg. */
4273 find_reloads_address_part (XEXP (ad, 1), &XEXP (ad, 1),
4274 INDEX_REG_CLASS, GET_MODE (ad), opnum,
4279 /* If the sum of two regs is not necessarily valid,
4280 reload the sum into a base reg.
4281 That will at least work. */
4282 find_reloads_address_part (ad, loc, BASE_REG_CLASS, Pmode,
4283 opnum, type, ind_levels);
4288 /* If we have an indexed stack slot, there are three possible reasons why
4289 it might be invalid: The index might need to be reloaded, the address
4290 might have been made by frame pointer elimination and hence have a
4291 constant out of range, or both reasons might apply.
4293 We can easily check for an index needing reload, but even if that is the
4294 case, we might also have an invalid constant. To avoid making the
4295 conservative assumption and requiring two reloads, we see if this address
4296 is valid when not interpreted strictly. If it is, the only problem is
4297 that the index needs a reload and find_reloads_address_1 will take care
4300 There is still a case when we might generate an extra reload,
4301 however. In certain cases eliminate_regs will return a MEM for a REG
4302 (see the code there for details). In those cases, memory_address_p
4303 applied to our address will return 0 so we will think that our offset
4304 must be too large. But it might indeed be valid and the only problem
4305 is that a MEM is present where a REG should be. This case should be
4306 very rare and there doesn't seem to be any way to avoid it.
4308 If we decide to do something here, it must be that
4309 `double_reg_address_ok' is true and that this address rtl was made by
4310 eliminate_regs. We generate a reload of the fp/sp/ap + constant and
4311 rework the sum so that the reload register will be added to the index.
4312 This is safe because we know the address isn't shared.
4314 We check for fp/ap/sp as both the first and second operand of the
4317 else if (GET_CODE (ad) == PLUS && GET_CODE (XEXP (ad, 1)) == CONST_INT
4318 && GET_CODE (XEXP (ad, 0)) == PLUS
4319 && (XEXP (XEXP (ad, 0), 0) == frame_pointer_rtx
4320 #if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
4321 || XEXP (XEXP (ad, 0), 0) == hard_frame_pointer_rtx
4323 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4324 || XEXP (XEXP (ad, 0), 0) == arg_pointer_rtx
4326 || XEXP (XEXP (ad, 0), 0) == stack_pointer_rtx)
4327 && ! memory_address_p (mode, ad))
4329 *loc = ad = gen_rtx (PLUS, GET_MODE (ad),
4330 plus_constant (XEXP (XEXP (ad, 0), 0),
4331 INTVAL (XEXP (ad, 1))),
4332 XEXP (XEXP (ad, 0), 1));
4333 find_reloads_address_part (XEXP (ad, 0), &XEXP (ad, 0), BASE_REG_CLASS,
4334 GET_MODE (ad), opnum, type, ind_levels);
4335 find_reloads_address_1 (XEXP (ad, 1), 1, &XEXP (ad, 1), opnum, type, 0);
4340 else if (GET_CODE (ad) == PLUS && GET_CODE (XEXP (ad, 1)) == CONST_INT
4341 && GET_CODE (XEXP (ad, 0)) == PLUS
4342 && (XEXP (XEXP (ad, 0), 1) == frame_pointer_rtx
4343 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4344 || XEXP (XEXP (ad, 0), 1) == hard_frame_pointer_rtx
4346 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4347 || XEXP (XEXP (ad, 0), 1) == arg_pointer_rtx
4349 || XEXP (XEXP (ad, 0), 1) == stack_pointer_rtx)
4350 && ! memory_address_p (mode, ad))
4352 *loc = ad = gen_rtx (PLUS, GET_MODE (ad),
4353 XEXP (XEXP (ad, 0), 0),
4354 plus_constant (XEXP (XEXP (ad, 0), 1),
4355 INTVAL (XEXP (ad, 1))));
4356 find_reloads_address_part (XEXP (ad, 1), &XEXP (ad, 1), BASE_REG_CLASS,
4357 GET_MODE (ad), opnum, type, ind_levels);
4358 find_reloads_address_1 (XEXP (ad, 0), 1, &XEXP (ad, 0), opnum, type, 0);
4363 /* See if address becomes valid when an eliminable register
4364 in a sum is replaced. */
4367 if (GET_CODE (ad) == PLUS)
4368 tem = subst_indexed_address (ad);
4369 if (tem != ad && strict_memory_address_p (mode, tem))
4371 /* Ok, we win that way. Replace any additional eliminable
4374 subst_reg_equivs_changed = 0;
4375 tem = subst_reg_equivs (tem);
4377 /* Make sure that didn't make the address invalid again. */
4379 if (! subst_reg_equivs_changed || strict_memory_address_p (mode, tem))
4386 /* If constants aren't valid addresses, reload the constant address
4388 if (CONSTANT_P (ad) && ! strict_memory_address_p (mode, ad))
4390 /* If AD is in address in the constant pool, the MEM rtx may be shared.
4391 Unshare it so we can safely alter it. */
4392 if (memrefloc && GET_CODE (ad) == SYMBOL_REF
4393 && CONSTANT_POOL_ADDRESS_P (ad))
4395 *memrefloc = copy_rtx (*memrefloc);
4396 loc = &XEXP (*memrefloc, 0);
4399 find_reloads_address_part (ad, loc, BASE_REG_CLASS, Pmode, opnum, type,
4404 return find_reloads_address_1 (ad, 0, loc, opnum, type, ind_levels);
4407 /* Find all pseudo regs appearing in AD
4408 that are eliminable in favor of equivalent values
4409 and do not have hard regs; replace them by their equivalents. */
4412 subst_reg_equivs (ad)
4415 register RTX_CODE code = GET_CODE (ad);
4433 register int regno = REGNO (ad);
4435 if (reg_equiv_constant[regno] != 0)
4437 subst_reg_equivs_changed = 1;
4438 return reg_equiv_constant[regno];
4444 /* Quickly dispose of a common case. */
4445 if (XEXP (ad, 0) == frame_pointer_rtx
4446 && GET_CODE (XEXP (ad, 1)) == CONST_INT)
4450 fmt = GET_RTX_FORMAT (code);
4451 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
4453 XEXP (ad, i) = subst_reg_equivs (XEXP (ad, i));
4457 /* Compute the sum of X and Y, making canonicalizations assumed in an
4458 address, namely: sum constant integers, surround the sum of two
4459 constants with a CONST, put the constant as the second operand, and
4460 group the constant on the outermost sum.
4462 This routine assumes both inputs are already in canonical form. */
4469 enum machine_mode mode = GET_MODE (x);
4471 if (mode == VOIDmode)
4472 mode = GET_MODE (y);
4474 if (mode == VOIDmode)
4477 if (GET_CODE (x) == CONST_INT)
4478 return plus_constant (y, INTVAL (x));
4479 else if (GET_CODE (y) == CONST_INT)
4480 return plus_constant (x, INTVAL (y));
4481 else if (CONSTANT_P (x))
4482 tem = x, x = y, y = tem;
4484 if (GET_CODE (x) == PLUS && CONSTANT_P (XEXP (x, 1)))
4485 return form_sum (XEXP (x, 0), form_sum (XEXP (x, 1), y));
4487 /* Note that if the operands of Y are specified in the opposite
4488 order in the recursive calls below, infinite recursion will occur. */
4489 if (GET_CODE (y) == PLUS && CONSTANT_P (XEXP (y, 1)))
4490 return form_sum (form_sum (x, XEXP (y, 0)), XEXP (y, 1));
4492 /* If both constant, encapsulate sum. Otherwise, just form sum. A
4493 constant will have been placed second. */
4494 if (CONSTANT_P (x) && CONSTANT_P (y))
4496 if (GET_CODE (x) == CONST)
4498 if (GET_CODE (y) == CONST)
4501 return gen_rtx (CONST, VOIDmode, gen_rtx (PLUS, mode, x, y));
4504 return gen_rtx (PLUS, mode, x, y);
4507 /* If ADDR is a sum containing a pseudo register that should be
4508 replaced with a constant (from reg_equiv_constant),
4509 return the result of doing so, and also apply the associative
4510 law so that the result is more likely to be a valid address.
4511 (But it is not guaranteed to be one.)
4513 Note that at most one register is replaced, even if more are
4514 replaceable. Also, we try to put the result into a canonical form
4515 so it is more likely to be a valid address.
4517 In all other cases, return ADDR. */
4520 subst_indexed_address (addr)
4523 rtx op0 = 0, op1 = 0, op2 = 0;
4527 if (GET_CODE (addr) == PLUS)
4529 /* Try to find a register to replace. */
4530 op0 = XEXP (addr, 0), op1 = XEXP (addr, 1), op2 = 0;
4531 if (GET_CODE (op0) == REG
4532 && (regno = REGNO (op0)) >= FIRST_PSEUDO_REGISTER
4533 && reg_renumber[regno] < 0
4534 && reg_equiv_constant[regno] != 0)
4535 op0 = reg_equiv_constant[regno];
4536 else if (GET_CODE (op1) == REG
4537 && (regno = REGNO (op1)) >= FIRST_PSEUDO_REGISTER
4538 && reg_renumber[regno] < 0
4539 && reg_equiv_constant[regno] != 0)
4540 op1 = reg_equiv_constant[regno];
4541 else if (GET_CODE (op0) == PLUS
4542 && (tem = subst_indexed_address (op0)) != op0)
4544 else if (GET_CODE (op1) == PLUS
4545 && (tem = subst_indexed_address (op1)) != op1)
4550 /* Pick out up to three things to add. */
4551 if (GET_CODE (op1) == PLUS)
4552 op2 = XEXP (op1, 1), op1 = XEXP (op1, 0);
4553 else if (GET_CODE (op0) == PLUS)
4554 op2 = op1, op1 = XEXP (op0, 1), op0 = XEXP (op0, 0);
4556 /* Compute the sum. */
4558 op1 = form_sum (op1, op2);
4560 op0 = form_sum (op0, op1);
4567 /* Record the pseudo registers we must reload into hard registers
4568 in a subexpression of a would-be memory address, X.
4569 (This function is not called if the address we find is strictly valid.)
4570 CONTEXT = 1 means we are considering regs as index regs,
4571 = 0 means we are considering them as base regs.
4573 OPNUM and TYPE specify the purpose of any reloads made.
4575 IND_LEVELS says how many levels of indirect addressing are
4576 supported at this point in the address.
4578 We return nonzero if X, as a whole, is reloaded or replaced. */
4580 /* Note that we take shortcuts assuming that no multi-reg machine mode
4581 occurs as part of an address.
4582 Also, this is not fully machine-customizable; it works for machines
4583 such as vaxes and 68000's and 32000's, but other possible machines
4584 could have addressing modes that this does not handle right. */
4587 find_reloads_address_1 (x, context, loc, opnum, type, ind_levels)
4592 enum reload_type type;
4595 register RTX_CODE code = GET_CODE (x);
4601 register rtx orig_op0 = XEXP (x, 0);
4602 register rtx orig_op1 = XEXP (x, 1);
4603 register RTX_CODE code0 = GET_CODE (orig_op0);
4604 register RTX_CODE code1 = GET_CODE (orig_op1);
4605 register rtx op0 = orig_op0;
4606 register rtx op1 = orig_op1;
4608 if (GET_CODE (op0) == SUBREG)
4610 op0 = SUBREG_REG (op0);
4611 code0 = GET_CODE (op0);
4612 if (code0 == REG && REGNO (op0) < FIRST_PSEUDO_REGISTER)
4613 op0 = gen_rtx (REG, word_mode,
4614 REGNO (op0) + SUBREG_WORD (orig_op0));
4617 if (GET_CODE (op1) == SUBREG)
4619 op1 = SUBREG_REG (op1);
4620 code1 = GET_CODE (op1);
4621 if (code1 == REG && REGNO (op1) < FIRST_PSEUDO_REGISTER)
4622 op1 = gen_rtx (REG, GET_MODE (op1),
4623 REGNO (op1) + SUBREG_WORD (orig_op1));
4626 if (code0 == MULT || code0 == SIGN_EXTEND || code0 == TRUNCATE
4627 || code0 == ZERO_EXTEND || code1 == MEM)
4629 find_reloads_address_1 (orig_op0, 1, &XEXP (x, 0), opnum, type,
4631 find_reloads_address_1 (orig_op1, 0, &XEXP (x, 1), opnum, type,
4635 else if (code1 == MULT || code1 == SIGN_EXTEND || code1 == TRUNCATE
4636 || code1 == ZERO_EXTEND || code0 == MEM)
4638 find_reloads_address_1 (orig_op0, 0, &XEXP (x, 0), opnum, type,
4640 find_reloads_address_1 (orig_op1, 1, &XEXP (x, 1), opnum, type,
4644 else if (code0 == CONST_INT || code0 == CONST
4645 || code0 == SYMBOL_REF || code0 == LABEL_REF)
4646 find_reloads_address_1 (orig_op1, 0, &XEXP (x, 1), opnum, type,
4649 else if (code1 == CONST_INT || code1 == CONST
4650 || code1 == SYMBOL_REF || code1 == LABEL_REF)
4651 find_reloads_address_1 (orig_op0, 0, &XEXP (x, 0), opnum, type,
4654 else if (code0 == REG && code1 == REG)
4656 if (REG_OK_FOR_INDEX_P (op0)
4657 && REG_OK_FOR_BASE_P (op1))
4659 else if (REG_OK_FOR_INDEX_P (op1)
4660 && REG_OK_FOR_BASE_P (op0))
4662 else if (REG_OK_FOR_BASE_P (op1))
4663 find_reloads_address_1 (orig_op0, 1, &XEXP (x, 0), opnum, type,
4665 else if (REG_OK_FOR_BASE_P (op0))
4666 find_reloads_address_1 (orig_op1, 1, &XEXP (x, 1), opnum, type,
4668 else if (REG_OK_FOR_INDEX_P (op1))
4669 find_reloads_address_1 (orig_op0, 0, &XEXP (x, 0), opnum, type,
4671 else if (REG_OK_FOR_INDEX_P (op0))
4672 find_reloads_address_1 (orig_op1, 0, &XEXP (x, 1), opnum, type,
4676 find_reloads_address_1 (orig_op0, 1, &XEXP (x, 0), opnum, type,
4678 find_reloads_address_1 (orig_op1, 0, &XEXP (x, 1), opnum, type,
4683 else if (code0 == REG)
4685 find_reloads_address_1 (orig_op0, 1, &XEXP (x, 0), opnum, type,
4687 find_reloads_address_1 (orig_op1, 0, &XEXP (x, 1), opnum, type,
4691 else if (code1 == REG)
4693 find_reloads_address_1 (orig_op1, 1, &XEXP (x, 1), opnum, type,
4695 find_reloads_address_1 (orig_op0, 0, &XEXP (x, 0), opnum, type,
4706 if (GET_CODE (XEXP (x, 0)) == REG)
4708 register int regno = REGNO (XEXP (x, 0));
4712 /* A register that is incremented cannot be constant! */
4713 if (regno >= FIRST_PSEUDO_REGISTER
4714 && reg_equiv_constant[regno] != 0)
4717 /* Handle a register that is equivalent to a memory location
4718 which cannot be addressed directly. */
4719 if (reg_equiv_address[regno] != 0)
4721 rtx tem = make_memloc (XEXP (x, 0), regno);
4722 /* First reload the memory location's address. */
4723 find_reloads_address (GET_MODE (tem), 0, XEXP (tem, 0),
4724 &XEXP (tem, 0), opnum, type, ind_levels);
4725 /* Put this inside a new increment-expression. */
4726 x = gen_rtx (GET_CODE (x), GET_MODE (x), tem);
4727 /* Proceed to reload that, as if it contained a register. */
4730 /* If we have a hard register that is ok as an index,
4731 don't make a reload. If an autoincrement of a nice register
4732 isn't "valid", it must be that no autoincrement is "valid".
4733 If that is true and something made an autoincrement anyway,
4734 this must be a special context where one is allowed.
4735 (For example, a "push" instruction.)
4736 We can't improve this address, so leave it alone. */
4738 /* Otherwise, reload the autoincrement into a suitable hard reg
4739 and record how much to increment by. */
4741 if (reg_renumber[regno] >= 0)
4742 regno = reg_renumber[regno];
4743 if ((regno >= FIRST_PSEUDO_REGISTER
4744 || !(context ? REGNO_OK_FOR_INDEX_P (regno)
4745 : REGNO_OK_FOR_BASE_P (regno))))
4750 = push_reload (x, NULL_RTX, loc, NULL_PTR,
4751 context ? INDEX_REG_CLASS : BASE_REG_CLASS,
4752 GET_MODE (x), GET_MODE (x), VOIDmode, 0,
4754 reload_inc[reloadnum]
4755 = find_inc_amount (PATTERN (this_insn), XEXP (x_orig, 0));
4760 /* Update the REG_INC notes. */
4762 for (link = REG_NOTES (this_insn);
4763 link; link = XEXP (link, 1))
4764 if (REG_NOTE_KIND (link) == REG_INC
4765 && REGNO (XEXP (link, 0)) == REGNO (XEXP (x_orig, 0)))
4766 push_replacement (&XEXP (link, 0), reloadnum, VOIDmode);
4772 else if (GET_CODE (XEXP (x, 0)) == MEM)
4774 /* This is probably the result of a substitution, by eliminate_regs,
4775 of an equivalent address for a pseudo that was not allocated to a
4776 hard register. Verify that the specified address is valid and
4777 reload it into a register. */
4778 rtx tem = XEXP (x, 0);
4782 /* Since we know we are going to reload this item, don't decrement
4783 for the indirection level.
4785 Note that this is actually conservative: it would be slightly
4786 more efficient to use the value of SPILL_INDIRECT_LEVELS from
4788 find_reloads_address (GET_MODE (x), &XEXP (x, 0),
4789 XEXP (XEXP (x, 0), 0), &XEXP (XEXP (x, 0), 0),
4790 opnum, type, ind_levels);
4792 reloadnum = push_reload (x, NULL_RTX, loc, NULL_PTR,
4793 context ? INDEX_REG_CLASS : BASE_REG_CLASS,
4794 GET_MODE (x), VOIDmode, 0, 0, opnum, type);
4795 reload_inc[reloadnum]
4796 = find_inc_amount (PATTERN (this_insn), XEXP (x, 0));
4798 link = FIND_REG_INC_NOTE (this_insn, tem);
4800 push_replacement (&XEXP (link, 0), reloadnum, VOIDmode);
4807 /* This is probably the result of a substitution, by eliminate_regs, of
4808 an equivalent address for a pseudo that was not allocated to a hard
4809 register. Verify that the specified address is valid and reload it
4812 Since we know we are going to reload this item, don't decrement for
4813 the indirection level.
4815 Note that this is actually conservative: it would be slightly more
4816 efficient to use the value of SPILL_INDIRECT_LEVELS from
4819 find_reloads_address (GET_MODE (x), loc, XEXP (x, 0), &XEXP (x, 0),
4820 opnum, type, ind_levels);
4821 push_reload (*loc, NULL_RTX, loc, NULL_PTR,
4822 context ? INDEX_REG_CLASS : BASE_REG_CLASS,
4823 GET_MODE (x), VOIDmode, 0, 0, opnum, type);
4828 register int regno = REGNO (x);
4830 if (reg_equiv_constant[regno] != 0)
4832 find_reloads_address_part (reg_equiv_constant[regno], loc,
4833 (context ? INDEX_REG_CLASS
4835 GET_MODE (x), opnum, type, ind_levels);
4839 #if 0 /* This might screw code in reload1.c to delete prior output-reload
4840 that feeds this insn. */
4841 if (reg_equiv_mem[regno] != 0)
4843 push_reload (reg_equiv_mem[regno], NULL_RTX, loc, NULL_PTR,
4844 context ? INDEX_REG_CLASS : BASE_REG_CLASS,
4845 GET_MODE (x), VOIDmode, 0, 0, opnum, type);
4850 if (reg_equiv_address[regno] != 0)
4852 x = make_memloc (x, regno);
4853 find_reloads_address (GET_MODE (x), 0, XEXP (x, 0), &XEXP (x, 0),
4854 opnum, type, ind_levels);
4857 if (reg_renumber[regno] >= 0)
4858 regno = reg_renumber[regno];
4860 if ((regno >= FIRST_PSEUDO_REGISTER
4861 || !(context ? REGNO_OK_FOR_INDEX_P (regno)
4862 : REGNO_OK_FOR_BASE_P (regno))))
4864 push_reload (x, NULL_RTX, loc, NULL_PTR,
4865 context ? INDEX_REG_CLASS : BASE_REG_CLASS,
4866 GET_MODE (x), VOIDmode, 0, 0, opnum, type);
4870 /* If a register appearing in an address is the subject of a CLOBBER
4871 in this insn, reload it into some other register to be safe.
4872 The CLOBBER is supposed to make the register unavailable
4873 from before this insn to after it. */
4874 if (regno_clobbered_p (regno, this_insn))
4876 push_reload (x, NULL_RTX, loc, NULL_PTR,
4877 context ? INDEX_REG_CLASS : BASE_REG_CLASS,
4878 GET_MODE (x), VOIDmode, 0, 0, opnum, type);
4885 if (GET_CODE (SUBREG_REG (x)) == REG)
4887 /* If this is a SUBREG of a hard register and the resulting register
4888 is of the wrong class, reload the whole SUBREG. This avoids
4889 needless copies if SUBREG_REG is multi-word. */
4890 if (REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER)
4892 int regno = REGNO (SUBREG_REG (x)) + SUBREG_WORD (x);
4894 if (! (context ? REGNO_OK_FOR_INDEX_P (regno)
4895 : REGNO_OK_FOR_BASE_P (regno)))
4897 push_reload (x, NULL_RTX, loc, NULL_PTR,
4898 context ? INDEX_REG_CLASS : BASE_REG_CLASS,
4899 GET_MODE (x), VOIDmode, 0, 0, opnum, type);
4903 /* If this is a SUBREG of a pseudo-register, and the pseudo-register
4904 is larger than the class size, then reload the whole SUBREG. */
4907 enum reg_class class = (context
4908 ? INDEX_REG_CLASS : BASE_REG_CLASS);
4909 if (CLASS_MAX_NREGS (class, GET_MODE (SUBREG_REG (x)))
4910 > reg_class_size[class])
4912 push_reload (x, NULL_RTX, loc, NULL_PTR, class,
4913 GET_MODE (x), VOIDmode, 0, 0, opnum, type);
4922 register char *fmt = GET_RTX_FORMAT (code);
4925 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
4928 find_reloads_address_1 (XEXP (x, i), context, &XEXP (x, i),
4929 opnum, type, ind_levels);
4936 /* X, which is found at *LOC, is a part of an address that needs to be
4937 reloaded into a register of class CLASS. If X is a constant, or if
4938 X is a PLUS that contains a constant, check that the constant is a
4939 legitimate operand and that we are supposed to be able to load
4940 it into the register.
4942 If not, force the constant into memory and reload the MEM instead.
4944 MODE is the mode to use, in case X is an integer constant.
4946 OPNUM and TYPE describe the purpose of any reloads made.
4948 IND_LEVELS says how many levels of indirect addressing this machine
4952 find_reloads_address_part (x, loc, class, mode, opnum, type, ind_levels)
4955 enum reg_class class;
4956 enum machine_mode mode;
4958 enum reload_type type;
4962 && (! LEGITIMATE_CONSTANT_P (x)
4963 || PREFERRED_RELOAD_CLASS (x, class) == NO_REGS))
4965 rtx tem = x = force_const_mem (mode, x);
4966 find_reloads_address (mode, &tem, XEXP (tem, 0), &XEXP (tem, 0),
4967 opnum, type, ind_levels);
4970 else if (GET_CODE (x) == PLUS
4971 && CONSTANT_P (XEXP (x, 1))
4972 && (! LEGITIMATE_CONSTANT_P (XEXP (x, 1))
4973 || PREFERRED_RELOAD_CLASS (XEXP (x, 1), class) == NO_REGS))
4975 rtx tem = force_const_mem (GET_MODE (x), XEXP (x, 1));
4977 x = gen_rtx (PLUS, GET_MODE (x), XEXP (x, 0), tem);
4978 find_reloads_address (mode, &tem, XEXP (tem, 0), &XEXP (tem, 0),
4979 opnum, type, ind_levels);
4982 push_reload (x, NULL_RTX, loc, NULL_PTR, class,
4983 mode, VOIDmode, 0, 0, opnum, type);
4986 /* Substitute into the current INSN the registers into which we have reloaded
4987 the things that need reloading. The array `replacements'
4988 says contains the locations of all pointers that must be changed
4989 and says what to replace them with.
4991 Return the rtx that X translates into; usually X, but modified. */
4998 for (i = 0; i < n_replacements; i++)
5000 register struct replacement *r = &replacements[i];
5001 register rtx reloadreg = reload_reg_rtx[r->what];
5004 /* Encapsulate RELOADREG so its machine mode matches what
5005 used to be there. Note that gen_lowpart_common will
5006 do the wrong thing if RELOADREG is multi-word. RELOADREG
5007 will always be a REG here. */
5008 if (GET_MODE (reloadreg) != r->mode && r->mode != VOIDmode)
5009 reloadreg = gen_rtx (REG, r->mode, REGNO (reloadreg));
5011 /* If we are putting this into a SUBREG and RELOADREG is a
5012 SUBREG, we would be making nested SUBREGs, so we have to fix
5013 this up. Note that r->where == &SUBREG_REG (*r->subreg_loc). */
5015 if (r->subreg_loc != 0 && GET_CODE (reloadreg) == SUBREG)
5017 if (GET_MODE (*r->subreg_loc)
5018 == GET_MODE (SUBREG_REG (reloadreg)))
5019 *r->subreg_loc = SUBREG_REG (reloadreg);
5022 *r->where = SUBREG_REG (reloadreg);
5023 SUBREG_WORD (*r->subreg_loc) += SUBREG_WORD (reloadreg);
5027 *r->where = reloadreg;
5029 /* If reload got no reg and isn't optional, something's wrong. */
5030 else if (! reload_optional[r->what])
5035 /* Make a copy of any replacements being done into X and move those copies
5036 to locations in Y, a copy of X. We only look at the highest level of
5040 copy_replacements (x, y)
5045 enum rtx_code code = GET_CODE (x);
5046 char *fmt = GET_RTX_FORMAT (code);
5047 struct replacement *r;
5049 /* We can't support X being a SUBREG because we might then need to know its
5050 location if something inside it was replaced. */
5054 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
5056 for (j = 0; j < n_replacements; j++)
5058 if (replacements[j].subreg_loc == &XEXP (x, i))
5060 r = &replacements[n_replacements++];
5061 r->where = replacements[j].where;
5062 r->subreg_loc = &XEXP (y, i);
5063 r->what = replacements[j].what;
5064 r->mode = replacements[j].mode;
5066 else if (replacements[j].where == &XEXP (x, i))
5068 r = &replacements[n_replacements++];
5069 r->where = &XEXP (y, i);
5071 r->what = replacements[j].what;
5072 r->mode = replacements[j].mode;
5077 /* If LOC was scheduled to be replaced by something, return the replacement.
5078 Otherwise, return *LOC. */
5081 find_replacement (loc)
5084 struct replacement *r;
5086 for (r = &replacements[0]; r < &replacements[n_replacements]; r++)
5088 rtx reloadreg = reload_reg_rtx[r->what];
5090 if (reloadreg && r->where == loc)
5092 if (r->mode != VOIDmode && GET_MODE (reloadreg) != r->mode)
5093 reloadreg = gen_rtx (REG, r->mode, REGNO (reloadreg));
5097 else if (reloadreg && r->subreg_loc == loc)
5099 /* RELOADREG must be either a REG or a SUBREG.
5101 ??? Is it actually still ever a SUBREG? If so, why? */
5103 if (GET_CODE (reloadreg) == REG)
5104 return gen_rtx (REG, GET_MODE (*loc),
5105 REGNO (reloadreg) + SUBREG_WORD (*loc));
5106 else if (GET_MODE (reloadreg) == GET_MODE (*loc))
5109 return gen_rtx (SUBREG, GET_MODE (*loc), SUBREG_REG (reloadreg),
5110 SUBREG_WORD (reloadreg) + SUBREG_WORD (*loc));
5117 /* Return nonzero if register in range [REGNO, ENDREGNO)
5118 appears either explicitly or implicitly in X
5119 other than being stored into (except for earlyclobber operands).
5121 References contained within the substructure at LOC do not count.
5122 LOC may be zero, meaning don't ignore anything.
5124 This is similar to refers_to_regno_p in rtlanal.c except that we
5125 look at equivalences for pseudos that didn't get hard registers. */
5128 refers_to_regno_for_reload_p (regno, endregno, x, loc)
5129 int regno, endregno;
5134 register RTX_CODE code;
5141 code = GET_CODE (x);
5148 /* If this is a pseudo, a hard register must not have been allocated.
5149 X must therefore either be a constant or be in memory. */
5150 if (i >= FIRST_PSEUDO_REGISTER)
5152 if (reg_equiv_memory_loc[i])
5153 return refers_to_regno_for_reload_p (regno, endregno,
5154 reg_equiv_memory_loc[i],
5157 if (reg_equiv_constant[i])
5163 return (endregno > i
5164 && regno < i + (i < FIRST_PSEUDO_REGISTER
5165 ? HARD_REGNO_NREGS (i, GET_MODE (x))
5169 /* If this is a SUBREG of a hard reg, we can see exactly which
5170 registers are being modified. Otherwise, handle normally. */
5171 if (GET_CODE (SUBREG_REG (x)) == REG
5172 && REGNO (SUBREG_REG (x)) < FIRST_PSEUDO_REGISTER)
5174 int inner_regno = REGNO (SUBREG_REG (x)) + SUBREG_WORD (x);
5176 = inner_regno + (inner_regno < FIRST_PSEUDO_REGISTER
5177 ? HARD_REGNO_NREGS (regno, GET_MODE (x)) : 1);
5179 return endregno > inner_regno && regno < inner_endregno;
5185 if (&SET_DEST (x) != loc
5186 /* Note setting a SUBREG counts as referring to the REG it is in for
5187 a pseudo but not for hard registers since we can
5188 treat each word individually. */
5189 && ((GET_CODE (SET_DEST (x)) == SUBREG
5190 && loc != &SUBREG_REG (SET_DEST (x))
5191 && GET_CODE (SUBREG_REG (SET_DEST (x))) == REG
5192 && REGNO (SUBREG_REG (SET_DEST (x))) >= FIRST_PSEUDO_REGISTER
5193 && refers_to_regno_for_reload_p (regno, endregno,
5194 SUBREG_REG (SET_DEST (x)),
5196 /* If the output is an earlyclobber operand, this is
5198 || ((GET_CODE (SET_DEST (x)) != REG
5199 || earlyclobber_operand_p (SET_DEST (x)))
5200 && refers_to_regno_for_reload_p (regno, endregno,
5201 SET_DEST (x), loc))))
5204 if (code == CLOBBER || loc == &SET_SRC (x))
5210 /* X does not match, so try its subexpressions. */
5212 fmt = GET_RTX_FORMAT (code);
5213 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
5215 if (fmt[i] == 'e' && loc != &XEXP (x, i))
5223 if (refers_to_regno_for_reload_p (regno, endregno,
5227 else if (fmt[i] == 'E')
5230 for (j = XVECLEN (x, i) - 1; j >=0; j--)
5231 if (loc != &XVECEXP (x, i, j)
5232 && refers_to_regno_for_reload_p (regno, endregno,
5233 XVECEXP (x, i, j), loc))
5240 /* Nonzero if modifying X will affect IN. If X is a register or a SUBREG,
5241 we check if any register number in X conflicts with the relevant register
5242 numbers. If X is a constant, return 0. If X is a MEM, return 1 iff IN
5243 contains a MEM (we don't bother checking for memory addresses that can't
5244 conflict because we expect this to be a rare case.
5246 This function is similar to reg_overlap_mention_p in rtlanal.c except
5247 that we look at equivalences for pseudos that didn't get hard registers. */
5250 reg_overlap_mentioned_for_reload_p (x, in)
5253 int regno, endregno;
5255 if (GET_CODE (x) == SUBREG)
5257 regno = REGNO (SUBREG_REG (x));
5258 if (regno < FIRST_PSEUDO_REGISTER)
5259 regno += SUBREG_WORD (x);
5261 else if (GET_CODE (x) == REG)
5265 /* If this is a pseudo, it must not have been assigned a hard register.
5266 Therefore, it must either be in memory or be a constant. */
5268 if (regno >= FIRST_PSEUDO_REGISTER)
5270 if (reg_equiv_memory_loc[regno])
5271 return refers_to_mem_for_reload_p (in);
5272 else if (reg_equiv_constant[regno])
5277 else if (CONSTANT_P (x))
5279 else if (GET_CODE (x) == MEM)
5280 return refers_to_mem_for_reload_p (in);
5281 else if (GET_CODE (x) == SCRATCH || GET_CODE (x) == PC
5282 || GET_CODE (x) == CC0)
5283 return reg_mentioned_p (x, in);
5287 endregno = regno + (regno < FIRST_PSEUDO_REGISTER
5288 ? HARD_REGNO_NREGS (regno, GET_MODE (x)) : 1);
5290 return refers_to_regno_for_reload_p (regno, endregno, in, NULL_PTR);
5293 /* Return nonzero if anything in X contains a MEM. Look also for pseudo
5297 refers_to_mem_for_reload_p (x)
5303 if (GET_CODE (x) == MEM)
5306 if (GET_CODE (x) == REG)
5307 return (REGNO (x) >= FIRST_PSEUDO_REGISTER
5308 && reg_equiv_memory_loc[REGNO (x)]);
5310 fmt = GET_RTX_FORMAT (GET_CODE (x));
5311 for (i = GET_RTX_LENGTH (GET_CODE (x)) - 1; i >= 0; i--)
5313 && (GET_CODE (XEXP (x, i)) == MEM
5314 || refers_to_mem_for_reload_p (XEXP (x, i))))
5320 /* Check the insns before INSN to see if there is a suitable register
5321 containing the same value as GOAL.
5322 If OTHER is -1, look for a register in class CLASS.
5323 Otherwise, just see if register number OTHER shares GOAL's value.
5325 Return an rtx for the register found, or zero if none is found.
5327 If RELOAD_REG_P is (short *)1,
5328 we reject any hard reg that appears in reload_reg_rtx
5329 because such a hard reg is also needed coming into this insn.
5331 If RELOAD_REG_P is any other nonzero value,
5332 it is a vector indexed by hard reg number
5333 and we reject any hard reg whose element in the vector is nonnegative
5334 as well as any that appears in reload_reg_rtx.
5336 If GOAL is zero, then GOALREG is a register number; we look
5337 for an equivalent for that register.
5339 MODE is the machine mode of the value we want an equivalence for.
5340 If GOAL is nonzero and not VOIDmode, then it must have mode MODE.
5342 This function is used by jump.c as well as in the reload pass.
5344 If GOAL is the sum of the stack pointer and a constant, we treat it
5345 as if it were a constant except that sp is required to be unchanging. */
5348 find_equiv_reg (goal, insn, class, other, reload_reg_p, goalreg, mode)
5351 enum reg_class class;
5353 short *reload_reg_p;
5355 enum machine_mode mode;
5357 register rtx p = insn;
5358 rtx goaltry, valtry, value, where;
5360 register int regno = -1;
5364 int goal_mem_addr_varies = 0;
5365 int need_stable_sp = 0;
5371 else if (GET_CODE (goal) == REG)
5372 regno = REGNO (goal);
5373 else if (GET_CODE (goal) == MEM)
5375 enum rtx_code code = GET_CODE (XEXP (goal, 0));
5376 if (MEM_VOLATILE_P (goal))
5378 if (flag_float_store && GET_MODE_CLASS (GET_MODE (goal)) == MODE_FLOAT)
5380 /* An address with side effects must be reexecuted. */
5391 else if (CONSTANT_P (goal))
5393 else if (GET_CODE (goal) == PLUS
5394 && XEXP (goal, 0) == stack_pointer_rtx
5395 && CONSTANT_P (XEXP (goal, 1)))
5396 goal_const = need_stable_sp = 1;
5400 /* On some machines, certain regs must always be rejected
5401 because they don't behave the way ordinary registers do. */
5403 #ifdef OVERLAPPING_REGNO_P
5404 if (regno >= 0 && regno < FIRST_PSEUDO_REGISTER
5405 && OVERLAPPING_REGNO_P (regno))
5409 /* Scan insns back from INSN, looking for one that copies
5410 a value into or out of GOAL.
5411 Stop and give up if we reach a label. */
5416 if (p == 0 || GET_CODE (p) == CODE_LABEL)
5418 if (GET_CODE (p) == INSN
5419 /* If we don't want spill regs ... */
5420 && (! (reload_reg_p != 0
5421 && reload_reg_p != (short *) (HOST_WIDE_INT) 1)
5422 /* ... then ignore insns introduced by reload; they aren't useful
5423 and can cause results in reload_as_needed to be different
5424 from what they were when calculating the need for spills.
5425 If we notice an input-reload insn here, we will reject it below,
5426 but it might hide a usable equivalent. That makes bad code.
5427 It may even abort: perhaps no reg was spilled for this insn
5428 because it was assumed we would find that equivalent. */
5429 || INSN_UID (p) < reload_first_uid))
5432 pat = single_set (p);
5433 /* First check for something that sets some reg equal to GOAL. */
5436 && true_regnum (SET_SRC (pat)) == regno
5437 && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0)
5440 && true_regnum (SET_DEST (pat)) == regno
5441 && (valueno = true_regnum (valtry = SET_SRC (pat))) >= 0)
5443 (goal_const && rtx_equal_p (SET_SRC (pat), goal)
5444 && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0)
5446 && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0
5447 && rtx_renumbered_equal_p (goal, SET_SRC (pat)))
5449 && (valueno = true_regnum (valtry = SET_SRC (pat))) >= 0
5450 && rtx_renumbered_equal_p (goal, SET_DEST (pat)))
5451 /* If we are looking for a constant,
5452 and something equivalent to that constant was copied
5453 into a reg, we can use that reg. */
5454 || (goal_const && (tem = find_reg_note (p, REG_EQUIV,
5456 && rtx_equal_p (XEXP (tem, 0), goal)
5457 && (valueno = true_regnum (valtry = SET_DEST (pat))) >= 0)
5458 || (goal_const && (tem = find_reg_note (p, REG_EQUIV,
5460 && GET_CODE (SET_DEST (pat)) == REG
5461 && GET_CODE (XEXP (tem, 0)) == CONST_DOUBLE
5462 && GET_MODE_CLASS (GET_MODE (XEXP (tem, 0))) == MODE_FLOAT
5463 && GET_CODE (goal) == CONST_INT
5464 && 0 != (goaltry = operand_subword (XEXP (tem, 0), 0, 0,
5466 && rtx_equal_p (goal, goaltry)
5467 && (valtry = operand_subword (SET_DEST (pat), 0, 0,
5469 && (valueno = true_regnum (valtry)) >= 0)
5470 || (goal_const && (tem = find_reg_note (p, REG_EQUIV,
5472 && GET_CODE (SET_DEST (pat)) == REG
5473 && GET_CODE (XEXP (tem, 0)) == CONST_DOUBLE
5474 && GET_MODE_CLASS (GET_MODE (XEXP (tem, 0))) == MODE_FLOAT
5475 && GET_CODE (goal) == CONST_INT
5476 && 0 != (goaltry = operand_subword (XEXP (tem, 0), 1, 0,
5478 && rtx_equal_p (goal, goaltry)
5480 = operand_subword (SET_DEST (pat), 1, 0, VOIDmode))
5481 && (valueno = true_regnum (valtry)) >= 0)))
5484 : ((unsigned) valueno < FIRST_PSEUDO_REGISTER
5485 && TEST_HARD_REG_BIT (reg_class_contents[(int) class],
5495 /* We found a previous insn copying GOAL into a suitable other reg VALUE
5496 (or copying VALUE into GOAL, if GOAL is also a register).
5497 Now verify that VALUE is really valid. */
5499 /* VALUENO is the register number of VALUE; a hard register. */
5501 /* Don't try to re-use something that is killed in this insn. We want
5502 to be able to trust REG_UNUSED notes. */
5503 if (find_reg_note (where, REG_UNUSED, value))
5506 /* If we propose to get the value from the stack pointer or if GOAL is
5507 a MEM based on the stack pointer, we need a stable SP. */
5508 if (valueno == STACK_POINTER_REGNUM
5509 || (goal_mem && reg_overlap_mentioned_for_reload_p (stack_pointer_rtx,
5513 /* Reject VALUE if the copy-insn moved the wrong sort of datum. */
5514 if (GET_MODE (value) != mode)
5517 /* Reject VALUE if it was loaded from GOAL
5518 and is also a register that appears in the address of GOAL. */
5520 if (goal_mem && value == SET_DEST (PATTERN (where))
5521 && refers_to_regno_for_reload_p (valueno,
5523 + HARD_REGNO_NREGS (valueno, mode)),
5527 /* Reject registers that overlap GOAL. */
5529 if (!goal_mem && !goal_const
5530 && regno + HARD_REGNO_NREGS (regno, mode) > valueno
5531 && regno < valueno + HARD_REGNO_NREGS (valueno, mode))
5534 /* Reject VALUE if it is one of the regs reserved for reloads.
5535 Reload1 knows how to reuse them anyway, and it would get
5536 confused if we allocated one without its knowledge.
5537 (Now that insns introduced by reload are ignored above,
5538 this case shouldn't happen, but I'm not positive.) */
5540 if (reload_reg_p != 0 && reload_reg_p != (short *) (HOST_WIDE_INT) 1
5541 && reload_reg_p[valueno] >= 0)
5544 /* On some machines, certain regs must always be rejected
5545 because they don't behave the way ordinary registers do. */
5547 #ifdef OVERLAPPING_REGNO_P
5548 if (OVERLAPPING_REGNO_P (valueno))
5552 nregs = HARD_REGNO_NREGS (regno, mode);
5553 valuenregs = HARD_REGNO_NREGS (valueno, mode);
5555 /* Reject VALUE if it is a register being used for an input reload
5556 even if it is not one of those reserved. */
5558 if (reload_reg_p != 0)
5561 for (i = 0; i < n_reloads; i++)
5562 if (reload_reg_rtx[i] != 0 && reload_in[i])
5564 int regno1 = REGNO (reload_reg_rtx[i]);
5565 int nregs1 = HARD_REGNO_NREGS (regno1,
5566 GET_MODE (reload_reg_rtx[i]));
5567 if (regno1 < valueno + valuenregs
5568 && regno1 + nregs1 > valueno)
5574 /* We must treat frame pointer as varying here,
5575 since it can vary--in a nonlocal goto as generated by expand_goto. */
5576 goal_mem_addr_varies = !CONSTANT_ADDRESS_P (XEXP (goal, 0));
5578 /* Now verify that the values of GOAL and VALUE remain unaltered
5579 until INSN is reached. */
5588 /* Don't trust the conversion past a function call
5589 if either of the two is in a call-clobbered register, or memory. */
5590 if (GET_CODE (p) == CALL_INSN
5591 && ((regno >= 0 && regno < FIRST_PSEUDO_REGISTER
5592 && call_used_regs[regno])
5594 (valueno >= 0 && valueno < FIRST_PSEUDO_REGISTER
5595 && call_used_regs[valueno])
5601 #ifdef NON_SAVING_SETJMP
5602 if (NON_SAVING_SETJMP && GET_CODE (p) == NOTE
5603 && NOTE_LINE_NUMBER (p) == NOTE_INSN_SETJMP)
5607 #ifdef INSN_CLOBBERS_REGNO_P
5608 if ((valueno >= 0 && valueno < FIRST_PSEUDO_REGISTER
5609 && INSN_CLOBBERS_REGNO_P (p, valueno))
5610 || (regno >= 0 && regno < FIRST_PSEUDO_REGISTER
5611 && INSN_CLOBBERS_REGNO_P (p, regno)))
5615 if (GET_RTX_CLASS (GET_CODE (p)) == 'i')
5617 /* If this insn P stores in either GOAL or VALUE, return 0.
5618 If GOAL is a memory ref and this insn writes memory, return 0.
5619 If GOAL is a memory ref and its address is not constant,
5620 and this insn P changes a register used in GOAL, return 0. */
5623 if (GET_CODE (pat) == SET || GET_CODE (pat) == CLOBBER)
5625 register rtx dest = SET_DEST (pat);
5626 while (GET_CODE (dest) == SUBREG
5627 || GET_CODE (dest) == ZERO_EXTRACT
5628 || GET_CODE (dest) == SIGN_EXTRACT
5629 || GET_CODE (dest) == STRICT_LOW_PART)
5630 dest = XEXP (dest, 0);
5631 if (GET_CODE (dest) == REG)
5633 register int xregno = REGNO (dest);
5635 if (REGNO (dest) < FIRST_PSEUDO_REGISTER)
5636 xnregs = HARD_REGNO_NREGS (xregno, GET_MODE (dest));
5639 if (xregno < regno + nregs && xregno + xnregs > regno)
5641 if (xregno < valueno + valuenregs
5642 && xregno + xnregs > valueno)
5644 if (goal_mem_addr_varies
5645 && reg_overlap_mentioned_for_reload_p (dest, goal))
5648 else if (goal_mem && GET_CODE (dest) == MEM
5649 && ! push_operand (dest, GET_MODE (dest)))
5651 else if (GET_CODE (dest) == MEM && regno >= FIRST_PSEUDO_REGISTER
5652 && reg_equiv_memory_loc[regno] != 0)
5654 else if (need_stable_sp && push_operand (dest, GET_MODE (dest)))
5657 else if (GET_CODE (pat) == PARALLEL)
5660 for (i = XVECLEN (pat, 0) - 1; i >= 0; i--)
5662 register rtx v1 = XVECEXP (pat, 0, i);
5663 if (GET_CODE (v1) == SET || GET_CODE (v1) == CLOBBER)
5665 register rtx dest = SET_DEST (v1);
5666 while (GET_CODE (dest) == SUBREG
5667 || GET_CODE (dest) == ZERO_EXTRACT
5668 || GET_CODE (dest) == SIGN_EXTRACT
5669 || GET_CODE (dest) == STRICT_LOW_PART)
5670 dest = XEXP (dest, 0);
5671 if (GET_CODE (dest) == REG)
5673 register int xregno = REGNO (dest);
5675 if (REGNO (dest) < FIRST_PSEUDO_REGISTER)
5676 xnregs = HARD_REGNO_NREGS (xregno, GET_MODE (dest));
5679 if (xregno < regno + nregs
5680 && xregno + xnregs > regno)
5682 if (xregno < valueno + valuenregs
5683 && xregno + xnregs > valueno)
5685 if (goal_mem_addr_varies
5686 && reg_overlap_mentioned_for_reload_p (dest,
5690 else if (goal_mem && GET_CODE (dest) == MEM
5691 && ! push_operand (dest, GET_MODE (dest)))
5693 else if (need_stable_sp
5694 && push_operand (dest, GET_MODE (dest)))
5700 if (GET_CODE (p) == CALL_INSN && CALL_INSN_FUNCTION_USAGE (p))
5704 for (link = CALL_INSN_FUNCTION_USAGE (p); XEXP (link, 1) != 0;
5705 link = XEXP (link, 1))
5707 pat = XEXP (link, 0);
5708 if (GET_CODE (pat) == CLOBBER)
5710 register rtx dest = SET_DEST (pat);
5711 while (GET_CODE (dest) == SUBREG
5712 || GET_CODE (dest) == ZERO_EXTRACT
5713 || GET_CODE (dest) == SIGN_EXTRACT
5714 || GET_CODE (dest) == STRICT_LOW_PART)
5715 dest = XEXP (dest, 0);
5716 if (GET_CODE (dest) == REG)
5718 register int xregno = REGNO (dest);
5720 if (REGNO (dest) < FIRST_PSEUDO_REGISTER)
5721 xnregs = HARD_REGNO_NREGS (xregno, GET_MODE (dest));
5724 if (xregno < regno + nregs
5725 && xregno + xnregs > regno)
5727 if (xregno < valueno + valuenregs
5728 && xregno + xnregs > valueno)
5730 if (goal_mem_addr_varies
5731 && reg_overlap_mentioned_for_reload_p (dest,
5735 else if (goal_mem && GET_CODE (dest) == MEM
5736 && ! push_operand (dest, GET_MODE (dest)))
5738 else if (need_stable_sp
5739 && push_operand (dest, GET_MODE (dest)))
5746 /* If this insn auto-increments or auto-decrements
5747 either regno or valueno, return 0 now.
5748 If GOAL is a memory ref and its address is not constant,
5749 and this insn P increments a register used in GOAL, return 0. */
5753 for (link = REG_NOTES (p); link; link = XEXP (link, 1))
5754 if (REG_NOTE_KIND (link) == REG_INC
5755 && GET_CODE (XEXP (link, 0)) == REG)
5757 register int incno = REGNO (XEXP (link, 0));
5758 if (incno < regno + nregs && incno >= regno)
5760 if (incno < valueno + valuenregs && incno >= valueno)
5762 if (goal_mem_addr_varies
5763 && reg_overlap_mentioned_for_reload_p (XEXP (link, 0),
5773 /* Find a place where INCED appears in an increment or decrement operator
5774 within X, and return the amount INCED is incremented or decremented by.
5775 The value is always positive. */
5778 find_inc_amount (x, inced)
5781 register enum rtx_code code = GET_CODE (x);
5787 register rtx addr = XEXP (x, 0);
5788 if ((GET_CODE (addr) == PRE_DEC
5789 || GET_CODE (addr) == POST_DEC
5790 || GET_CODE (addr) == PRE_INC
5791 || GET_CODE (addr) == POST_INC)
5792 && XEXP (addr, 0) == inced)
5793 return GET_MODE_SIZE (GET_MODE (x));
5796 fmt = GET_RTX_FORMAT (code);
5797 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
5801 register int tem = find_inc_amount (XEXP (x, i), inced);
5808 for (j = XVECLEN (x, i) - 1; j >= 0; j--)
5810 register int tem = find_inc_amount (XVECEXP (x, i, j), inced);
5820 /* Return 1 if register REGNO is the subject of a clobber in insn INSN. */
5823 regno_clobbered_p (regno, insn)
5827 if (GET_CODE (PATTERN (insn)) == CLOBBER
5828 && GET_CODE (XEXP (PATTERN (insn), 0)) == REG)
5829 return REGNO (XEXP (PATTERN (insn), 0)) == regno;
5831 if (GET_CODE (PATTERN (insn)) == PARALLEL)
5833 int i = XVECLEN (PATTERN (insn), 0) - 1;
5837 rtx elt = XVECEXP (PATTERN (insn), 0, i);
5838 if (GET_CODE (elt) == CLOBBER && GET_CODE (XEXP (elt, 0)) == REG
5839 && REGNO (XEXP (elt, 0)) == regno)
5847 static char *reload_when_needed_name[] =
5850 "RELOAD_FOR_OUTPUT",
5852 "RELOAD_FOR_INPUT_ADDRESS",
5853 "RELOAD_FOR_OUTPUT_ADDRESS",
5854 "RELOAD_FOR_OPERAND_ADDRESS",
5855 "RELOAD_FOR_OPADDR_ADDR",
5857 "RELOAD_FOR_OTHER_ADDRESS"
5860 static char *reg_class_names[] = REG_CLASS_NAMES;
5862 /* This function is used to print the variables set by 'find_reloads' */
5869 fprintf (stderr, "\nn_reloads = %d\n", n_reloads);
5871 for (r = 0; r < n_reloads; r++)
5873 fprintf (stderr, "\nRELOAD %d\n", r);
5877 fprintf (stderr, "\nreload_in (%s) = ",
5878 GET_MODE_NAME (reload_inmode[r]));
5879 debug_rtx (reload_in[r]);
5884 fprintf (stderr, "\nreload_out (%s) = ",
5885 GET_MODE_NAME (reload_outmode[r]));
5886 debug_rtx (reload_out[r]);
5889 fprintf (stderr, "%s, ", reg_class_names[(int) reload_reg_class[r]]);
5891 fprintf (stderr, "%s (opnum = %d)",
5892 reload_when_needed_name[(int)reload_when_needed[r]],
5895 if (reload_optional[r])
5896 fprintf (stderr, ", optional");
5899 fprintf (stderr, ", inc by %d\n", reload_inc[r]);
5901 if (reload_nocombine[r])
5902 fprintf (stderr, ", can combine");
5904 if (reload_secondary_p[r])
5905 fprintf (stderr, ", secondary_reload_p");
5907 if (reload_in_reg[r])
5909 fprintf (stderr, "\nreload_in_reg:\t\t\t");
5910 debug_rtx (reload_in_reg[r]);
5913 if (reload_reg_rtx[r])
5915 fprintf (stderr, "\nreload_reg_rtx:\t\t\t");
5916 debug_rtx (reload_reg_rtx[r]);
5919 if (reload_secondary_in_reload[r] != -1)
5921 fprintf (stderr, "\nsecondary_in_reload = ");
5922 fprintf (stderr, "%d ", reload_secondary_in_reload[r]);
5925 if (reload_secondary_out_reload[r] != -1)
5927 if (reload_secondary_in_reload[r] != -1)
5928 fprintf (stderr, ", secondary_out_reload = ");
5930 fprintf (stderr, "\nsecondary_out_reload = ");
5932 fprintf (stderr, "%d", reload_secondary_out_reload[r]);
5936 if (reload_secondary_in_icode[r] != CODE_FOR_nothing)
5938 fprintf (stderr, "\nsecondary_in_icode = ");
5939 fprintf (stderr, "%s", insn_name[r]);
5942 if (reload_secondary_out_icode[r] != CODE_FOR_nothing)
5944 if (reload_secondary_in_icode[r] != CODE_FOR_nothing)
5945 fprintf (stderr, ", secondary_out_icode = ");
5947 fprintf (stderr, "\nsecondary_out_icode = ");
5949 fprintf (stderr, "%s ", insn_name[r]);
5951 fprintf (stderr, "\n");
5954 fprintf (stderr, "\n");