1 /* Search an insn for pseudo regs that must be in hard regs and are not.
2 Copyright (C) 1987, 88, 89, 92-97, 1998 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"
105 #ifndef REGISTER_MOVE_COST
106 #define REGISTER_MOVE_COST(x, y) 2
109 #ifndef REGNO_MODE_OK_FOR_BASE_P
110 #define REGNO_MODE_OK_FOR_BASE_P(REGNO, MODE) REGNO_OK_FOR_BASE_P (REGNO)
113 #ifndef REG_MODE_OK_FOR_BASE_P
114 #define REG_MODE_OK_FOR_BASE_P(REGNO, MODE) REG_OK_FOR_BASE_P (REGNO)
117 /* The variables set up by `find_reloads' are:
119 n_reloads number of distinct reloads needed; max reload # + 1
120 tables indexed by reload number
121 reload_in rtx for value to reload from
122 reload_out rtx for where to store reload-reg afterward if nec
123 (often the same as reload_in)
124 reload_reg_class enum reg_class, saying what regs to reload into
125 reload_inmode enum machine_mode; mode this operand should have
126 when reloaded, on input.
127 reload_outmode enum machine_mode; mode this operand should have
128 when reloaded, on output.
129 reload_optional char, nonzero for an optional reload.
130 Optional reloads are ignored unless the
131 value is already sitting in a register.
132 reload_nongroup char, nonzero when a reload must use a register
133 not already allocated to a group.
134 reload_inc int, positive amount to increment or decrement by if
135 reload_in is a PRE_DEC, PRE_INC, POST_DEC, POST_INC.
136 Ignored otherwise (don't assume it is zero).
137 reload_in_reg rtx. A reg for which reload_in is the equivalent.
138 If reload_in is a symbol_ref which came from
139 reg_equiv_constant, then this is the pseudo
140 which has that symbol_ref as equivalent.
141 reload_reg_rtx rtx. This is the register to reload into.
142 If it is zero when `find_reloads' returns,
143 you must find a suitable register in the class
144 specified by reload_reg_class, and store here
145 an rtx for that register with mode from
146 reload_inmode or reload_outmode.
147 reload_nocombine char, nonzero if this reload shouldn't be
148 combined with another reload.
149 reload_opnum int, operand number being reloaded. This is
150 used to group related reloads and need not always
151 be equal to the actual operand number in the insn,
152 though it current will be; for in-out operands, it
153 is one of the two operand numbers.
154 reload_when_needed enum, classifies reload as needed either for
155 addressing an input reload, addressing an output,
156 for addressing a non-reloaded mem ref,
157 or for unspecified purposes (i.e., more than one
159 reload_secondary_p int, 1 if this is a secondary register for one
161 reload_secondary_in_reload
162 reload_secondary_out_reload
163 int, gives the reload number of a secondary
164 reload, when needed; otherwise -1
165 reload_secondary_in_icode
166 reload_secondary_out_icode
167 enum insn_code, if a secondary reload is required,
168 gives the INSN_CODE that uses the secondary
169 reload as a scratch register, or CODE_FOR_nothing
170 if the secondary reload register is to be an
171 intermediate register. */
174 rtx reload_in
[MAX_RELOADS
];
175 rtx reload_out
[MAX_RELOADS
];
176 enum reg_class reload_reg_class
[MAX_RELOADS
];
177 enum machine_mode reload_inmode
[MAX_RELOADS
];
178 enum machine_mode reload_outmode
[MAX_RELOADS
];
179 rtx reload_reg_rtx
[MAX_RELOADS
];
180 char reload_optional
[MAX_RELOADS
];
181 char reload_nongroup
[MAX_RELOADS
];
182 int reload_inc
[MAX_RELOADS
];
183 rtx reload_in_reg
[MAX_RELOADS
];
184 char reload_nocombine
[MAX_RELOADS
];
185 int reload_opnum
[MAX_RELOADS
];
186 enum reload_type reload_when_needed
[MAX_RELOADS
];
187 int reload_secondary_p
[MAX_RELOADS
];
188 int reload_secondary_in_reload
[MAX_RELOADS
];
189 int reload_secondary_out_reload
[MAX_RELOADS
];
190 enum insn_code reload_secondary_in_icode
[MAX_RELOADS
];
191 enum insn_code reload_secondary_out_icode
[MAX_RELOADS
];
193 /* All the "earlyclobber" operands of the current insn
194 are recorded here. */
196 rtx reload_earlyclobbers
[MAX_RECOG_OPERANDS
];
198 int reload_n_operands
;
200 /* Replacing reloads.
202 If `replace_reloads' is nonzero, then as each reload is recorded
203 an entry is made for it in the table `replacements'.
204 Then later `subst_reloads' can look through that table and
205 perform all the replacements needed. */
207 /* Nonzero means record the places to replace. */
208 static int replace_reloads
;
210 /* Each replacement is recorded with a structure like this. */
213 rtx
*where
; /* Location to store in */
214 rtx
*subreg_loc
; /* Location of SUBREG if WHERE is inside
215 a SUBREG; 0 otherwise. */
216 int what
; /* which reload this is for */
217 enum machine_mode mode
; /* mode it must have */
220 static struct replacement replacements
[MAX_RECOG_OPERANDS
* ((MAX_REGS_PER_ADDRESS
* 2) + 1)];
222 /* Number of replacements currently recorded. */
223 static int n_replacements
;
225 /* Used to track what is modified by an operand. */
228 int reg_flag
; /* Nonzero if referencing a register. */
229 int safe
; /* Nonzero if this can't conflict with anything. */
230 rtx base
; /* Base address for MEM. */
231 HOST_WIDE_INT start
; /* Starting offset or register number. */
232 HOST_WIDE_INT end
; /* Ending offset or register number. */
235 /* MEM-rtx's created for pseudo-regs in stack slots not directly addressable;
236 (see reg_equiv_address). */
237 static rtx memlocs
[MAX_RECOG_OPERANDS
* ((MAX_REGS_PER_ADDRESS
* 2) + 1)];
238 static int n_memlocs
;
240 #ifdef SECONDARY_MEMORY_NEEDED
242 /* Save MEMs needed to copy from one class of registers to another. One MEM
243 is used per mode, but normally only one or two modes are ever used.
245 We keep two versions, before and after register elimination. The one
246 after register elimination is record separately for each operand. This
247 is done in case the address is not valid to be sure that we separately
250 static rtx secondary_memlocs
[NUM_MACHINE_MODES
];
251 static rtx secondary_memlocs_elim
[NUM_MACHINE_MODES
][MAX_RECOG_OPERANDS
];
254 /* The instruction we are doing reloads for;
255 so we can test whether a register dies in it. */
256 static rtx this_insn
;
258 /* Nonzero if this instruction is a user-specified asm with operands. */
259 static int this_insn_is_asm
;
261 /* If hard_regs_live_known is nonzero,
262 we can tell which hard regs are currently live,
263 at least enough to succeed in choosing dummy reloads. */
264 static int hard_regs_live_known
;
266 /* Indexed by hard reg number,
267 element is nonnegative if hard reg has been spilled.
268 This vector is passed to `find_reloads' as an argument
269 and is not changed here. */
270 static short *static_reload_reg_p
;
272 /* Set to 1 in subst_reg_equivs if it changes anything. */
273 static int subst_reg_equivs_changed
;
275 /* On return from push_reload, holds the reload-number for the OUT
276 operand, which can be different for that from the input operand. */
277 static int output_reloadnum
;
279 /* Compare two RTX's. */
280 #define MATCHES(x, y) \
281 (x == y || (x != 0 && (GET_CODE (x) == REG \
282 ? GET_CODE (y) == REG && REGNO (x) == REGNO (y) \
283 : rtx_equal_p (x, y) && ! side_effects_p (x))))
285 /* Indicates if two reloads purposes are for similar enough things that we
286 can merge their reloads. */
287 #define MERGABLE_RELOADS(when1, when2, op1, op2) \
288 ((when1) == RELOAD_OTHER || (when2) == RELOAD_OTHER \
289 || ((when1) == (when2) && (op1) == (op2)) \
290 || ((when1) == RELOAD_FOR_INPUT && (when2) == RELOAD_FOR_INPUT) \
291 || ((when1) == RELOAD_FOR_OPERAND_ADDRESS \
292 && (when2) == RELOAD_FOR_OPERAND_ADDRESS) \
293 || ((when1) == RELOAD_FOR_OTHER_ADDRESS \
294 && (when2) == RELOAD_FOR_OTHER_ADDRESS))
296 /* Nonzero if these two reload purposes produce RELOAD_OTHER when merged. */
297 #define MERGE_TO_OTHER(when1, when2, op1, op2) \
298 ((when1) != (when2) \
299 || ! ((op1) == (op2) \
300 || (when1) == RELOAD_FOR_INPUT \
301 || (when1) == RELOAD_FOR_OPERAND_ADDRESS \
302 || (when1) == RELOAD_FOR_OTHER_ADDRESS))
304 /* If we are going to reload an address, compute the reload type to
306 #define ADDR_TYPE(type) \
307 ((type) == RELOAD_FOR_INPUT_ADDRESS \
308 ? RELOAD_FOR_INPADDR_ADDRESS \
309 : ((type) == RELOAD_FOR_OUTPUT_ADDRESS \
310 ? RELOAD_FOR_OUTADDR_ADDRESS \
313 #ifdef HAVE_SECONDARY_RELOADS
314 static int push_secondary_reload
PROTO((int, rtx
, int, int, enum reg_class
,
315 enum machine_mode
, enum reload_type
,
318 static enum reg_class find_valid_class
PROTO((enum machine_mode
, int));
319 static int push_reload
PROTO((rtx
, rtx
, rtx
*, rtx
*, enum reg_class
,
320 enum machine_mode
, enum machine_mode
,
321 int, int, int, enum reload_type
));
322 static void push_replacement
PROTO((rtx
*, int, enum machine_mode
));
323 static void combine_reloads
PROTO((void));
324 static rtx find_dummy_reload
PROTO((rtx
, rtx
, rtx
*, rtx
*,
325 enum machine_mode
, enum machine_mode
,
326 enum reg_class
, int, int));
327 static int earlyclobber_operand_p
PROTO((rtx
));
328 static int hard_reg_set_here_p
PROTO((int, int, rtx
));
329 static struct decomposition decompose
PROTO((rtx
));
330 static int immune_p
PROTO((rtx
, rtx
, struct decomposition
));
331 static int alternative_allows_memconst
PROTO((char *, int));
332 static rtx find_reloads_toplev
PROTO((rtx
, int, enum reload_type
, int, int));
333 static rtx make_memloc
PROTO((rtx
, int));
334 static int find_reloads_address
PROTO((enum machine_mode
, rtx
*, rtx
, rtx
*,
335 int, enum reload_type
, int, rtx
));
336 static rtx subst_reg_equivs
PROTO((rtx
));
337 static rtx subst_indexed_address
PROTO((rtx
));
338 static int find_reloads_address_1
PROTO((enum machine_mode
, rtx
, int, rtx
*,
339 int, enum reload_type
,int, rtx
));
340 static void find_reloads_address_part
PROTO((rtx
, rtx
*, enum reg_class
,
341 enum machine_mode
, int,
342 enum reload_type
, int));
343 static int find_inc_amount
PROTO((rtx
, rtx
));
345 #ifdef HAVE_SECONDARY_RELOADS
347 /* Determine if any secondary reloads are needed for loading (if IN_P is
348 non-zero) or storing (if IN_P is zero) X to or from a reload register of
349 register class RELOAD_CLASS in mode RELOAD_MODE. If secondary reloads
350 are needed, push them.
352 Return the reload number of the secondary reload we made, or -1 if
353 we didn't need one. *PICODE is set to the insn_code to use if we do
354 need a secondary reload. */
357 push_secondary_reload (in_p
, x
, opnum
, optional
, reload_class
, reload_mode
,
363 enum reg_class reload_class
;
364 enum machine_mode reload_mode
;
365 enum reload_type type
;
366 enum insn_code
*picode
;
368 enum reg_class
class = NO_REGS
;
369 enum machine_mode mode
= reload_mode
;
370 enum insn_code icode
= CODE_FOR_nothing
;
371 enum reg_class t_class
= NO_REGS
;
372 enum machine_mode t_mode
= VOIDmode
;
373 enum insn_code t_icode
= CODE_FOR_nothing
;
374 enum reload_type secondary_type
;
375 int s_reload
, t_reload
= -1;
377 if (type
== RELOAD_FOR_INPUT_ADDRESS
378 || type
== RELOAD_FOR_OUTPUT_ADDRESS
379 || type
== RELOAD_FOR_INPADDR_ADDRESS
380 || type
== RELOAD_FOR_OUTADDR_ADDRESS
)
381 secondary_type
= type
;
383 secondary_type
= in_p
? RELOAD_FOR_INPUT_ADDRESS
: RELOAD_FOR_OUTPUT_ADDRESS
;
385 *picode
= CODE_FOR_nothing
;
387 /* If X is a paradoxical SUBREG, use the inner value to determine both the
388 mode and object being reloaded. */
389 if (GET_CODE (x
) == SUBREG
390 && (GET_MODE_SIZE (GET_MODE (x
))
391 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x
)))))
394 reload_mode
= GET_MODE (x
);
397 /* If X is a pseudo-register that has an equivalent MEM (actually, if it
398 is still a pseudo-register by now, it *must* have an equivalent MEM
399 but we don't want to assume that), use that equivalent when seeing if
400 a secondary reload is needed since whether or not a reload is needed
401 might be sensitive to the form of the MEM. */
403 if (GET_CODE (x
) == REG
&& REGNO (x
) >= FIRST_PSEUDO_REGISTER
404 && reg_equiv_mem
[REGNO (x
)] != 0)
405 x
= reg_equiv_mem
[REGNO (x
)];
407 #ifdef SECONDARY_INPUT_RELOAD_CLASS
409 class = SECONDARY_INPUT_RELOAD_CLASS (reload_class
, reload_mode
, x
);
412 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
414 class = SECONDARY_OUTPUT_RELOAD_CLASS (reload_class
, reload_mode
, x
);
417 /* If we don't need any secondary registers, done. */
418 if (class == NO_REGS
)
421 /* Get a possible insn to use. If the predicate doesn't accept X, don't
424 icode
= (in_p
? reload_in_optab
[(int) reload_mode
]
425 : reload_out_optab
[(int) reload_mode
]);
427 if (icode
!= CODE_FOR_nothing
428 && insn_operand_predicate
[(int) icode
][in_p
]
429 && (! (insn_operand_predicate
[(int) icode
][in_p
]) (x
, reload_mode
)))
430 icode
= CODE_FOR_nothing
;
432 /* If we will be using an insn, see if it can directly handle the reload
433 register we will be using. If it can, the secondary reload is for a
434 scratch register. If it can't, we will use the secondary reload for
435 an intermediate register and require a tertiary reload for the scratch
438 if (icode
!= CODE_FOR_nothing
)
440 /* If IN_P is non-zero, the reload register will be the output in
441 operand 0. If IN_P is zero, the reload register will be the input
442 in operand 1. Outputs should have an initial "=", which we must
445 char insn_letter
= insn_operand_constraint
[(int) icode
][!in_p
][in_p
];
446 enum reg_class insn_class
447 = (insn_letter
== 'r' ? GENERAL_REGS
448 : REG_CLASS_FROM_LETTER (insn_letter
));
450 if (insn_class
== NO_REGS
451 || (in_p
&& insn_operand_constraint
[(int) icode
][!in_p
][0] != '=')
452 /* The scratch register's constraint must start with "=&". */
453 || insn_operand_constraint
[(int) icode
][2][0] != '='
454 || insn_operand_constraint
[(int) icode
][2][1] != '&')
457 if (reg_class_subset_p (reload_class
, insn_class
))
458 mode
= insn_operand_mode
[(int) icode
][2];
461 char t_letter
= insn_operand_constraint
[(int) icode
][2][2];
463 t_mode
= insn_operand_mode
[(int) icode
][2];
464 t_class
= (t_letter
== 'r' ? GENERAL_REGS
465 : REG_CLASS_FROM_LETTER (t_letter
));
467 icode
= CODE_FOR_nothing
;
471 /* This case isn't valid, so fail. Reload is allowed to use the same
472 register for RELOAD_FOR_INPUT_ADDRESS and RELOAD_FOR_INPUT reloads, but
473 in the case of a secondary register, we actually need two different
474 registers for correct code. We fail here to prevent the possibility of
475 silently generating incorrect code later.
477 The convention is that secondary input reloads are valid only if the
478 secondary_class is different from class. If you have such a case, you
479 can not use secondary reloads, you must work around the problem some
482 Allow this when MODE is not reload_mode and assume that the generated
483 code handles this case (it does on the Alpha, which is the only place
484 this currently happens). */
486 if (in_p
&& class == reload_class
&& mode
== reload_mode
)
489 /* If we need a tertiary reload, see if we have one we can reuse or else
492 if (t_class
!= NO_REGS
)
494 for (t_reload
= 0; t_reload
< n_reloads
; t_reload
++)
495 if (reload_secondary_p
[t_reload
]
496 && (reg_class_subset_p (t_class
, reload_reg_class
[t_reload
])
497 || reg_class_subset_p (reload_reg_class
[t_reload
], t_class
))
498 && ((in_p
&& reload_inmode
[t_reload
] == t_mode
)
499 || (! in_p
&& reload_outmode
[t_reload
] == t_mode
))
500 && ((in_p
&& (reload_secondary_in_icode
[t_reload
]
501 == CODE_FOR_nothing
))
502 || (! in_p
&&(reload_secondary_out_icode
[t_reload
]
503 == CODE_FOR_nothing
)))
504 && (reg_class_size
[(int) t_class
] == 1 || SMALL_REGISTER_CLASSES
)
505 && MERGABLE_RELOADS (secondary_type
,
506 reload_when_needed
[t_reload
],
507 opnum
, reload_opnum
[t_reload
]))
510 reload_inmode
[t_reload
] = t_mode
;
512 reload_outmode
[t_reload
] = t_mode
;
514 if (reg_class_subset_p (t_class
, reload_reg_class
[t_reload
]))
515 reload_reg_class
[t_reload
] = t_class
;
517 reload_opnum
[t_reload
] = MIN (reload_opnum
[t_reload
], opnum
);
518 reload_optional
[t_reload
] &= optional
;
519 reload_secondary_p
[t_reload
] = 1;
520 if (MERGE_TO_OTHER (secondary_type
, reload_when_needed
[t_reload
],
521 opnum
, reload_opnum
[t_reload
]))
522 reload_when_needed
[t_reload
] = RELOAD_OTHER
;
525 if (t_reload
== n_reloads
)
527 /* We need to make a new tertiary reload for this register class. */
528 reload_in
[t_reload
] = reload_out
[t_reload
] = 0;
529 reload_reg_class
[t_reload
] = t_class
;
530 reload_inmode
[t_reload
] = in_p
? t_mode
: VOIDmode
;
531 reload_outmode
[t_reload
] = ! in_p
? t_mode
: VOIDmode
;
532 reload_reg_rtx
[t_reload
] = 0;
533 reload_optional
[t_reload
] = optional
;
534 reload_nongroup
[t_reload
] = 0;
535 reload_inc
[t_reload
] = 0;
536 /* Maybe we could combine these, but it seems too tricky. */
537 reload_nocombine
[t_reload
] = 1;
538 reload_in_reg
[t_reload
] = 0;
539 reload_opnum
[t_reload
] = opnum
;
540 reload_when_needed
[t_reload
] = secondary_type
;
541 reload_secondary_in_reload
[t_reload
] = -1;
542 reload_secondary_out_reload
[t_reload
] = -1;
543 reload_secondary_in_icode
[t_reload
] = CODE_FOR_nothing
;
544 reload_secondary_out_icode
[t_reload
] = CODE_FOR_nothing
;
545 reload_secondary_p
[t_reload
] = 1;
551 /* See if we can reuse an existing secondary reload. */
552 for (s_reload
= 0; s_reload
< n_reloads
; s_reload
++)
553 if (reload_secondary_p
[s_reload
]
554 && (reg_class_subset_p (class, reload_reg_class
[s_reload
])
555 || reg_class_subset_p (reload_reg_class
[s_reload
], class))
556 && ((in_p
&& reload_inmode
[s_reload
] == mode
)
557 || (! in_p
&& reload_outmode
[s_reload
] == mode
))
558 && ((in_p
&& reload_secondary_in_reload
[s_reload
] == t_reload
)
559 || (! in_p
&& reload_secondary_out_reload
[s_reload
] == t_reload
))
560 && ((in_p
&& reload_secondary_in_icode
[s_reload
] == t_icode
)
561 || (! in_p
&& reload_secondary_out_icode
[s_reload
] == t_icode
))
562 && (reg_class_size
[(int) class] == 1 || SMALL_REGISTER_CLASSES
)
563 && MERGABLE_RELOADS (secondary_type
, reload_when_needed
[s_reload
],
564 opnum
, reload_opnum
[s_reload
]))
567 reload_inmode
[s_reload
] = mode
;
569 reload_outmode
[s_reload
] = mode
;
571 if (reg_class_subset_p (class, reload_reg_class
[s_reload
]))
572 reload_reg_class
[s_reload
] = class;
574 reload_opnum
[s_reload
] = MIN (reload_opnum
[s_reload
], opnum
);
575 reload_optional
[s_reload
] &= optional
;
576 reload_secondary_p
[s_reload
] = 1;
577 if (MERGE_TO_OTHER (secondary_type
, reload_when_needed
[s_reload
],
578 opnum
, reload_opnum
[s_reload
]))
579 reload_when_needed
[s_reload
] = RELOAD_OTHER
;
582 if (s_reload
== n_reloads
)
584 #ifdef SECONDARY_MEMORY_NEEDED
585 /* If we need a memory location to copy between the two reload regs,
586 set it up now. Note that we do the input case before making
587 the reload and the output case after. This is due to the
588 way reloads are output. */
590 if (in_p
&& icode
== CODE_FOR_nothing
591 && SECONDARY_MEMORY_NEEDED (class, reload_class
, mode
))
592 get_secondary_mem (x
, reload_mode
, opnum
, type
);
595 /* We need to make a new secondary reload for this register class. */
596 reload_in
[s_reload
] = reload_out
[s_reload
] = 0;
597 reload_reg_class
[s_reload
] = class;
599 reload_inmode
[s_reload
] = in_p
? mode
: VOIDmode
;
600 reload_outmode
[s_reload
] = ! in_p
? mode
: VOIDmode
;
601 reload_reg_rtx
[s_reload
] = 0;
602 reload_optional
[s_reload
] = optional
;
603 reload_nongroup
[s_reload
] = 0;
604 reload_inc
[s_reload
] = 0;
605 /* Maybe we could combine these, but it seems too tricky. */
606 reload_nocombine
[s_reload
] = 1;
607 reload_in_reg
[s_reload
] = 0;
608 reload_opnum
[s_reload
] = opnum
;
609 reload_when_needed
[s_reload
] = secondary_type
;
610 reload_secondary_in_reload
[s_reload
] = in_p
? t_reload
: -1;
611 reload_secondary_out_reload
[s_reload
] = ! in_p
? t_reload
: -1;
612 reload_secondary_in_icode
[s_reload
] = in_p
? t_icode
: CODE_FOR_nothing
;
613 reload_secondary_out_icode
[s_reload
]
614 = ! in_p
? t_icode
: CODE_FOR_nothing
;
615 reload_secondary_p
[s_reload
] = 1;
619 #ifdef SECONDARY_MEMORY_NEEDED
620 if (! in_p
&& icode
== CODE_FOR_nothing
621 && SECONDARY_MEMORY_NEEDED (reload_class
, class, mode
))
622 get_secondary_mem (x
, mode
, opnum
, type
);
629 #endif /* HAVE_SECONDARY_RELOADS */
631 #ifdef SECONDARY_MEMORY_NEEDED
633 /* Return a memory location that will be used to copy X in mode MODE.
634 If we haven't already made a location for this mode in this insn,
635 call find_reloads_address on the location being returned. */
638 get_secondary_mem (x
, mode
, opnum
, type
)
640 enum machine_mode mode
;
642 enum reload_type type
;
647 /* By default, if MODE is narrower than a word, widen it to a word.
648 This is required because most machines that require these memory
649 locations do not support short load and stores from all registers
650 (e.g., FP registers). */
652 #ifdef SECONDARY_MEMORY_NEEDED_MODE
653 mode
= SECONDARY_MEMORY_NEEDED_MODE (mode
);
655 if (GET_MODE_BITSIZE (mode
) < BITS_PER_WORD
)
656 mode
= mode_for_size (BITS_PER_WORD
, GET_MODE_CLASS (mode
), 0);
659 /* If we already have made a MEM for this operand in MODE, return it. */
660 if (secondary_memlocs_elim
[(int) mode
][opnum
] != 0)
661 return secondary_memlocs_elim
[(int) mode
][opnum
];
663 /* If this is the first time we've tried to get a MEM for this mode,
664 allocate a new one. `something_changed' in reload will get set
665 by noticing that the frame size has changed. */
667 if (secondary_memlocs
[(int) mode
] == 0)
669 #ifdef SECONDARY_MEMORY_NEEDED_RTX
670 secondary_memlocs
[(int) mode
] = SECONDARY_MEMORY_NEEDED_RTX (mode
);
672 secondary_memlocs
[(int) mode
]
673 = assign_stack_local (mode
, GET_MODE_SIZE (mode
), 0);
677 /* Get a version of the address doing any eliminations needed. If that
678 didn't give us a new MEM, make a new one if it isn't valid. */
680 loc
= eliminate_regs (secondary_memlocs
[(int) mode
], VOIDmode
, NULL_RTX
);
681 mem_valid
= strict_memory_address_p (mode
, XEXP (loc
, 0));
683 if (! mem_valid
&& loc
== secondary_memlocs
[(int) mode
])
684 loc
= copy_rtx (loc
);
686 /* The only time the call below will do anything is if the stack
687 offset is too large. In that case IND_LEVELS doesn't matter, so we
688 can just pass a zero. Adjust the type to be the address of the
689 corresponding object. If the address was valid, save the eliminated
690 address. If it wasn't valid, we need to make a reload each time, so
695 type
= (type
== RELOAD_FOR_INPUT
? RELOAD_FOR_INPUT_ADDRESS
696 : type
== RELOAD_FOR_OUTPUT
? RELOAD_FOR_OUTPUT_ADDRESS
699 find_reloads_address (mode
, NULL_PTR
, XEXP (loc
, 0), &XEXP (loc
, 0),
703 secondary_memlocs_elim
[(int) mode
][opnum
] = loc
;
707 /* Clear any secondary memory locations we've made. */
710 clear_secondary_mem ()
712 bzero ((char *) secondary_memlocs
, sizeof secondary_memlocs
);
714 #endif /* SECONDARY_MEMORY_NEEDED */
716 /* Find the largest class for which every register number plus N is valid in
717 M1 (if in range). Abort if no such class exists. */
719 static enum reg_class
720 find_valid_class (m1
, n
)
721 enum machine_mode m1
;
726 enum reg_class best_class
;
729 for (class = 1; class < N_REG_CLASSES
; class++)
732 for (regno
= 0; regno
< FIRST_PSEUDO_REGISTER
&& ! bad
; regno
++)
733 if (TEST_HARD_REG_BIT (reg_class_contents
[class], regno
)
734 && TEST_HARD_REG_BIT (reg_class_contents
[class], regno
+ n
)
735 && ! HARD_REGNO_MODE_OK (regno
+ n
, m1
))
738 if (! bad
&& reg_class_size
[class] > best_size
)
739 best_class
= class, best_size
= reg_class_size
[class];
748 /* Record one reload that needs to be performed.
749 IN is an rtx saying where the data are to be found before this instruction.
750 OUT says where they must be stored after the instruction.
751 (IN is zero for data not read, and OUT is zero for data not written.)
752 INLOC and OUTLOC point to the places in the instructions where
753 IN and OUT were found.
754 If IN and OUT are both non-zero, it means the same register must be used
755 to reload both IN and OUT.
757 CLASS is a register class required for the reloaded data.
758 INMODE is the machine mode that the instruction requires
759 for the reg that replaces IN and OUTMODE is likewise for OUT.
761 If IN is zero, then OUT's location and mode should be passed as
764 STRICT_LOW is the 1 if there is a containing STRICT_LOW_PART rtx.
766 OPTIONAL nonzero means this reload does not need to be performed:
767 it can be discarded if that is more convenient.
769 OPNUM and TYPE say what the purpose of this reload is.
771 The return value is the reload-number for this reload.
773 If both IN and OUT are nonzero, in some rare cases we might
774 want to make two separate reloads. (Actually we never do this now.)
775 Therefore, the reload-number for OUT is stored in
776 output_reloadnum when we return; the return value applies to IN.
777 Usually (presently always), when IN and OUT are nonzero,
778 the two reload-numbers are equal, but the caller should be careful to
782 push_reload (in
, out
, inloc
, outloc
, class,
783 inmode
, outmode
, strict_low
, optional
, opnum
, type
)
784 register rtx in
, out
;
786 enum reg_class
class;
787 enum machine_mode inmode
, outmode
;
791 enum reload_type type
;
795 int dont_remove_subreg
= 0;
796 rtx
*in_subreg_loc
= 0, *out_subreg_loc
= 0;
797 int secondary_in_reload
= -1, secondary_out_reload
= -1;
798 enum insn_code secondary_in_icode
= CODE_FOR_nothing
;
799 enum insn_code secondary_out_icode
= CODE_FOR_nothing
;
801 /* INMODE and/or OUTMODE could be VOIDmode if no mode
802 has been specified for the operand. In that case,
803 use the operand's mode as the mode to reload. */
804 if (inmode
== VOIDmode
&& in
!= 0)
805 inmode
= GET_MODE (in
);
806 if (outmode
== VOIDmode
&& out
!= 0)
807 outmode
= GET_MODE (out
);
809 /* If IN is a pseudo register everywhere-equivalent to a constant, and
810 it is not in a hard register, reload straight from the constant,
811 since we want to get rid of such pseudo registers.
812 Often this is done earlier, but not always in find_reloads_address. */
813 if (in
!= 0 && GET_CODE (in
) == REG
)
815 register int regno
= REGNO (in
);
817 if (regno
>= FIRST_PSEUDO_REGISTER
&& reg_renumber
[regno
] < 0
818 && reg_equiv_constant
[regno
] != 0)
819 in
= reg_equiv_constant
[regno
];
822 /* Likewise for OUT. Of course, OUT will never be equivalent to
823 an actual constant, but it might be equivalent to a memory location
824 (in the case of a parameter). */
825 if (out
!= 0 && GET_CODE (out
) == REG
)
827 register int regno
= REGNO (out
);
829 if (regno
>= FIRST_PSEUDO_REGISTER
&& reg_renumber
[regno
] < 0
830 && reg_equiv_constant
[regno
] != 0)
831 out
= reg_equiv_constant
[regno
];
834 /* If we have a read-write operand with an address side-effect,
835 change either IN or OUT so the side-effect happens only once. */
836 if (in
!= 0 && out
!= 0 && GET_CODE (in
) == MEM
&& rtx_equal_p (in
, out
))
838 if (GET_CODE (XEXP (in
, 0)) == POST_INC
839 || GET_CODE (XEXP (in
, 0)) == POST_DEC
)
840 in
= gen_rtx_MEM (GET_MODE (in
), XEXP (XEXP (in
, 0), 0));
841 if (GET_CODE (XEXP (in
, 0)) == PRE_INC
842 || GET_CODE (XEXP (in
, 0)) == PRE_DEC
)
843 out
= gen_rtx_MEM (GET_MODE (out
), XEXP (XEXP (out
, 0), 0));
846 /* If we are reloading a (SUBREG constant ...), really reload just the
847 inside expression in its own mode. Similarly for (SUBREG (PLUS ...)).
848 If we have (SUBREG:M1 (MEM:M2 ...) ...) (or an inner REG that is still
849 a pseudo and hence will become a MEM) with M1 wider than M2 and the
850 register is a pseudo, also reload the inside expression.
851 For machines that extend byte loads, do this for any SUBREG of a pseudo
852 where both M1 and M2 are a word or smaller, M1 is wider than M2, and
853 M2 is an integral mode that gets extended when loaded.
854 Similar issue for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where
855 either M1 is not valid for R or M2 is wider than a word but we only
856 need one word to store an M2-sized quantity in R.
857 (However, if OUT is nonzero, we need to reload the reg *and*
858 the subreg, so do nothing here, and let following statement handle it.)
860 Note that the case of (SUBREG (CONST_INT...)...) is handled elsewhere;
861 we can't handle it here because CONST_INT does not indicate a mode.
863 Similarly, we must reload the inside expression if we have a
864 STRICT_LOW_PART (presumably, in == out in the cas).
866 Also reload the inner expression if it does not require a secondary
867 reload but the SUBREG does.
869 Finally, reload the inner expression if it is a register that is in
870 the class whose registers cannot be referenced in a different size
871 and M1 is not the same size as M2. If SUBREG_WORD is nonzero, we
872 cannot reload just the inside since we might end up with the wrong
875 if (in
!= 0 && GET_CODE (in
) == SUBREG
&& SUBREG_WORD (in
) == 0
876 #ifdef CLASS_CANNOT_CHANGE_SIZE
877 && class != CLASS_CANNOT_CHANGE_SIZE
879 && (CONSTANT_P (SUBREG_REG (in
))
880 || GET_CODE (SUBREG_REG (in
)) == PLUS
882 || (((GET_CODE (SUBREG_REG (in
)) == REG
883 && REGNO (SUBREG_REG (in
)) >= FIRST_PSEUDO_REGISTER
)
884 || GET_CODE (SUBREG_REG (in
)) == MEM
)
885 && ((GET_MODE_SIZE (inmode
)
886 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (in
))))
887 #ifdef LOAD_EXTEND_OP
888 || (GET_MODE_SIZE (inmode
) <= UNITS_PER_WORD
889 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in
)))
891 && (GET_MODE_SIZE (inmode
)
892 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (in
))))
893 && INTEGRAL_MODE_P (GET_MODE (SUBREG_REG (in
)))
894 && LOAD_EXTEND_OP (GET_MODE (SUBREG_REG (in
))) != NIL
)
896 #ifdef WORD_REGISTER_OPERATIONS
897 || ((GET_MODE_SIZE (inmode
)
898 < GET_MODE_SIZE (GET_MODE (SUBREG_REG (in
))))
899 && ((GET_MODE_SIZE (inmode
) - 1) / UNITS_PER_WORD
==
900 ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in
))) - 1)
904 || (GET_CODE (SUBREG_REG (in
)) == REG
905 && REGNO (SUBREG_REG (in
)) < FIRST_PSEUDO_REGISTER
906 /* The case where out is nonzero
907 is handled differently in the following statement. */
908 && (out
== 0 || SUBREG_WORD (in
) == 0)
909 && ((GET_MODE_SIZE (inmode
) <= UNITS_PER_WORD
910 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in
)))
912 && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in
)))
914 != HARD_REGNO_NREGS (REGNO (SUBREG_REG (in
)),
915 GET_MODE (SUBREG_REG (in
)))))
916 || ! HARD_REGNO_MODE_OK ((REGNO (SUBREG_REG (in
))
919 #ifdef SECONDARY_INPUT_RELOAD_CLASS
920 || (SECONDARY_INPUT_RELOAD_CLASS (class, inmode
, in
) != NO_REGS
921 && (SECONDARY_INPUT_RELOAD_CLASS (class,
922 GET_MODE (SUBREG_REG (in
)),
926 #ifdef CLASS_CANNOT_CHANGE_SIZE
927 || (GET_CODE (SUBREG_REG (in
)) == REG
928 && REGNO (SUBREG_REG (in
)) < FIRST_PSEUDO_REGISTER
929 && (TEST_HARD_REG_BIT
930 (reg_class_contents
[(int) CLASS_CANNOT_CHANGE_SIZE
],
931 REGNO (SUBREG_REG (in
))))
932 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in
)))
933 != GET_MODE_SIZE (inmode
)))
937 in_subreg_loc
= inloc
;
938 inloc
= &SUBREG_REG (in
);
940 #if ! defined (LOAD_EXTEND_OP) && ! defined (WORD_REGISTER_OPERATIONS)
941 if (GET_CODE (in
) == MEM
)
942 /* This is supposed to happen only for paradoxical subregs made by
943 combine.c. (SUBREG (MEM)) isn't supposed to occur other ways. */
944 if (GET_MODE_SIZE (GET_MODE (in
)) > GET_MODE_SIZE (inmode
))
947 inmode
= GET_MODE (in
);
950 /* Similar issue for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where
951 either M1 is not valid for R or M2 is wider than a word but we only
952 need one word to store an M2-sized quantity in R.
954 However, we must reload the inner reg *as well as* the subreg in
957 /* Similar issue for (SUBREG constant ...) if it was not handled by the
958 code above. This can happen if SUBREG_WORD != 0. */
960 if (in
!= 0 && GET_CODE (in
) == SUBREG
961 && (CONSTANT_P (SUBREG_REG (in
))
962 || (GET_CODE (SUBREG_REG (in
)) == REG
963 && REGNO (SUBREG_REG (in
)) < FIRST_PSEUDO_REGISTER
964 && (! HARD_REGNO_MODE_OK (REGNO (SUBREG_REG (in
))
967 || (GET_MODE_SIZE (inmode
) <= UNITS_PER_WORD
968 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (in
)))
970 && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in
)))
972 != HARD_REGNO_NREGS (REGNO (SUBREG_REG (in
)),
973 GET_MODE (SUBREG_REG (in
)))))))))
975 /* This relies on the fact that emit_reload_insns outputs the
976 instructions for input reloads of type RELOAD_OTHER in the same
977 order as the reloads. Thus if the outer reload is also of type
978 RELOAD_OTHER, we are guaranteed that this inner reload will be
979 output before the outer reload. */
980 push_reload (SUBREG_REG (in
), NULL_RTX
, &SUBREG_REG (in
), NULL_PTR
,
981 find_valid_class (inmode
, SUBREG_WORD (in
)),
982 VOIDmode
, VOIDmode
, 0, 0, opnum
, type
);
983 dont_remove_subreg
= 1;
986 /* Similarly for paradoxical and problematical SUBREGs on the output.
987 Note that there is no reason we need worry about the previous value
988 of SUBREG_REG (out); even if wider than out,
989 storing in a subreg is entitled to clobber it all
990 (except in the case of STRICT_LOW_PART,
991 and in that case the constraint should label it input-output.) */
992 if (out
!= 0 && GET_CODE (out
) == SUBREG
&& SUBREG_WORD (out
) == 0
993 #ifdef CLASS_CANNOT_CHANGE_SIZE
994 && class != CLASS_CANNOT_CHANGE_SIZE
996 && (CONSTANT_P (SUBREG_REG (out
))
998 || (((GET_CODE (SUBREG_REG (out
)) == REG
999 && REGNO (SUBREG_REG (out
)) >= FIRST_PSEUDO_REGISTER
)
1000 || GET_CODE (SUBREG_REG (out
)) == MEM
)
1001 && ((GET_MODE_SIZE (outmode
)
1002 > GET_MODE_SIZE (GET_MODE (SUBREG_REG (out
))))
1003 #ifdef WORD_REGISTER_OPERATIONS
1004 || ((GET_MODE_SIZE (outmode
)
1005 < GET_MODE_SIZE (GET_MODE (SUBREG_REG (out
))))
1006 && ((GET_MODE_SIZE (outmode
) - 1) / UNITS_PER_WORD
==
1007 ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (out
))) - 1)
1011 || (GET_CODE (SUBREG_REG (out
)) == REG
1012 && REGNO (SUBREG_REG (out
)) < FIRST_PSEUDO_REGISTER
1013 && ((GET_MODE_SIZE (outmode
) <= UNITS_PER_WORD
1014 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (out
)))
1016 && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (out
)))
1018 != HARD_REGNO_NREGS (REGNO (SUBREG_REG (out
)),
1019 GET_MODE (SUBREG_REG (out
)))))
1020 || ! HARD_REGNO_MODE_OK ((REGNO (SUBREG_REG (out
))
1021 + SUBREG_WORD (out
)),
1023 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
1024 || (SECONDARY_OUTPUT_RELOAD_CLASS (class, outmode
, out
) != NO_REGS
1025 && (SECONDARY_OUTPUT_RELOAD_CLASS (class,
1026 GET_MODE (SUBREG_REG (out
)),
1030 #ifdef CLASS_CANNOT_CHANGE_SIZE
1031 || (GET_CODE (SUBREG_REG (out
)) == REG
1032 && REGNO (SUBREG_REG (out
)) < FIRST_PSEUDO_REGISTER
1033 && (TEST_HARD_REG_BIT
1034 (reg_class_contents
[(int) CLASS_CANNOT_CHANGE_SIZE
],
1035 REGNO (SUBREG_REG (out
))))
1036 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (out
)))
1037 != GET_MODE_SIZE (outmode
)))
1041 out_subreg_loc
= outloc
;
1042 outloc
= &SUBREG_REG (out
);
1044 #if ! defined (LOAD_EXTEND_OP) && ! defined (WORD_REGISTER_OPERATIONS)
1045 if (GET_CODE (out
) == MEM
1046 && GET_MODE_SIZE (GET_MODE (out
)) > GET_MODE_SIZE (outmode
))
1049 outmode
= GET_MODE (out
);
1052 /* Similar issue for (SUBREG:M1 (REG:M2 ...) ...) for a hard register R where
1053 either M1 is not valid for R or M2 is wider than a word but we only
1054 need one word to store an M2-sized quantity in R.
1056 However, we must reload the inner reg *as well as* the subreg in
1057 that case. In this case, the inner reg is an in-out reload. */
1059 if (out
!= 0 && GET_CODE (out
) == SUBREG
1060 && GET_CODE (SUBREG_REG (out
)) == REG
1061 && REGNO (SUBREG_REG (out
)) < FIRST_PSEUDO_REGISTER
1062 && (! HARD_REGNO_MODE_OK (REGNO (SUBREG_REG (out
)) + SUBREG_WORD (out
),
1064 || (GET_MODE_SIZE (outmode
) <= UNITS_PER_WORD
1065 && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (out
)))
1067 && ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (out
)))
1069 != HARD_REGNO_NREGS (REGNO (SUBREG_REG (out
)),
1070 GET_MODE (SUBREG_REG (out
)))))))
1072 /* This relies on the fact that emit_reload_insns outputs the
1073 instructions for output reloads of type RELOAD_OTHER in reverse
1074 order of the reloads. Thus if the outer reload is also of type
1075 RELOAD_OTHER, we are guaranteed that this inner reload will be
1076 output after the outer reload. */
1077 dont_remove_subreg
= 1;
1078 push_reload (SUBREG_REG (out
), SUBREG_REG (out
), &SUBREG_REG (out
),
1080 find_valid_class (outmode
, SUBREG_WORD (out
)),
1081 VOIDmode
, VOIDmode
, 0, 0,
1082 opnum
, RELOAD_OTHER
);
1085 /* If IN appears in OUT, we can't share any input-only reload for IN. */
1086 if (in
!= 0 && out
!= 0 && GET_CODE (out
) == MEM
1087 && (GET_CODE (in
) == REG
|| GET_CODE (in
) == MEM
)
1088 && reg_overlap_mentioned_for_reload_p (in
, XEXP (out
, 0)))
1091 /* If IN is a SUBREG of a hard register, make a new REG. This
1092 simplifies some of the cases below. */
1094 if (in
!= 0 && GET_CODE (in
) == SUBREG
&& GET_CODE (SUBREG_REG (in
)) == REG
1095 && REGNO (SUBREG_REG (in
)) < FIRST_PSEUDO_REGISTER
1096 && ! dont_remove_subreg
)
1097 in
= gen_rtx_REG (GET_MODE (in
),
1098 REGNO (SUBREG_REG (in
)) + SUBREG_WORD (in
));
1100 /* Similarly for OUT. */
1101 if (out
!= 0 && GET_CODE (out
) == SUBREG
1102 && GET_CODE (SUBREG_REG (out
)) == REG
1103 && REGNO (SUBREG_REG (out
)) < FIRST_PSEUDO_REGISTER
1104 && ! dont_remove_subreg
)
1105 out
= gen_rtx_REG (GET_MODE (out
),
1106 REGNO (SUBREG_REG (out
)) + SUBREG_WORD (out
));
1108 /* Narrow down the class of register wanted if that is
1109 desirable on this machine for efficiency. */
1111 class = PREFERRED_RELOAD_CLASS (in
, class);
1113 /* Output reloads may need analogous treatment, different in detail. */
1114 #ifdef PREFERRED_OUTPUT_RELOAD_CLASS
1116 class = PREFERRED_OUTPUT_RELOAD_CLASS (out
, class);
1119 /* Make sure we use a class that can handle the actual pseudo
1120 inside any subreg. For example, on the 386, QImode regs
1121 can appear within SImode subregs. Although GENERAL_REGS
1122 can handle SImode, QImode needs a smaller class. */
1123 #ifdef LIMIT_RELOAD_CLASS
1125 class = LIMIT_RELOAD_CLASS (inmode
, class);
1126 else if (in
!= 0 && GET_CODE (in
) == SUBREG
)
1127 class = LIMIT_RELOAD_CLASS (GET_MODE (SUBREG_REG (in
)), class);
1130 class = LIMIT_RELOAD_CLASS (outmode
, class);
1131 if (out
!= 0 && GET_CODE (out
) == SUBREG
)
1132 class = LIMIT_RELOAD_CLASS (GET_MODE (SUBREG_REG (out
)), class);
1135 /* Verify that this class is at least possible for the mode that
1137 if (this_insn_is_asm
)
1139 enum machine_mode mode
;
1140 if (GET_MODE_SIZE (inmode
) > GET_MODE_SIZE (outmode
))
1144 if (mode
== VOIDmode
)
1146 error_for_asm (this_insn
, "cannot reload integer constant operand in `asm'");
1151 outmode
= word_mode
;
1153 for (i
= 0; i
< FIRST_PSEUDO_REGISTER
; i
++)
1154 if (HARD_REGNO_MODE_OK (i
, mode
)
1155 && TEST_HARD_REG_BIT (reg_class_contents
[(int) class], i
))
1157 int nregs
= HARD_REGNO_NREGS (i
, mode
);
1160 for (j
= 1; j
< nregs
; j
++)
1161 if (! TEST_HARD_REG_BIT (reg_class_contents
[(int) class], i
+ j
))
1166 if (i
== FIRST_PSEUDO_REGISTER
)
1168 error_for_asm (this_insn
, "impossible register constraint in `asm'");
1173 if (class == NO_REGS
)
1176 /* We can use an existing reload if the class is right
1177 and at least one of IN and OUT is a match
1178 and the other is at worst neutral.
1179 (A zero compared against anything is neutral.)
1181 If SMALL_REGISTER_CLASSES, don't use existing reloads unless they are
1182 for the same thing since that can cause us to need more reload registers
1183 than we otherwise would. */
1185 for (i
= 0; i
< n_reloads
; i
++)
1186 if ((reg_class_subset_p (class, reload_reg_class
[i
])
1187 || reg_class_subset_p (reload_reg_class
[i
], class))
1188 /* If the existing reload has a register, it must fit our class. */
1189 && (reload_reg_rtx
[i
] == 0
1190 || TEST_HARD_REG_BIT (reg_class_contents
[(int) class],
1191 true_regnum (reload_reg_rtx
[i
])))
1192 && ((in
!= 0 && MATCHES (reload_in
[i
], in
) && ! dont_share
1193 && (out
== 0 || reload_out
[i
] == 0 || MATCHES (reload_out
[i
], out
)))
1195 (out
!= 0 && MATCHES (reload_out
[i
], out
)
1196 && (in
== 0 || reload_in
[i
] == 0 || MATCHES (reload_in
[i
], in
))))
1197 && (reg_class_size
[(int) class] == 1 || SMALL_REGISTER_CLASSES
)
1198 && MERGABLE_RELOADS (type
, reload_when_needed
[i
],
1199 opnum
, reload_opnum
[i
]))
1202 /* Reloading a plain reg for input can match a reload to postincrement
1203 that reg, since the postincrement's value is the right value.
1204 Likewise, it can match a preincrement reload, since we regard
1205 the preincrementation as happening before any ref in this insn
1206 to that register. */
1208 for (i
= 0; i
< n_reloads
; i
++)
1209 if ((reg_class_subset_p (class, reload_reg_class
[i
])
1210 || reg_class_subset_p (reload_reg_class
[i
], class))
1211 /* If the existing reload has a register, it must fit our class. */
1212 && (reload_reg_rtx
[i
] == 0
1213 || TEST_HARD_REG_BIT (reg_class_contents
[(int) class],
1214 true_regnum (reload_reg_rtx
[i
])))
1215 && out
== 0 && reload_out
[i
] == 0 && reload_in
[i
] != 0
1216 && ((GET_CODE (in
) == REG
1217 && (GET_CODE (reload_in
[i
]) == POST_INC
1218 || GET_CODE (reload_in
[i
]) == POST_DEC
1219 || GET_CODE (reload_in
[i
]) == PRE_INC
1220 || GET_CODE (reload_in
[i
]) == PRE_DEC
)
1221 && MATCHES (XEXP (reload_in
[i
], 0), in
))
1223 (GET_CODE (reload_in
[i
]) == REG
1224 && (GET_CODE (in
) == POST_INC
1225 || GET_CODE (in
) == POST_DEC
1226 || GET_CODE (in
) == PRE_INC
1227 || GET_CODE (in
) == PRE_DEC
)
1228 && MATCHES (XEXP (in
, 0), reload_in
[i
])))
1229 && (reg_class_size
[(int) class] == 1 || SMALL_REGISTER_CLASSES
)
1230 && MERGABLE_RELOADS (type
, reload_when_needed
[i
],
1231 opnum
, reload_opnum
[i
]))
1233 /* Make sure reload_in ultimately has the increment,
1234 not the plain register. */
1235 if (GET_CODE (in
) == REG
)
1242 /* See if we need a secondary reload register to move between CLASS
1243 and IN or CLASS and OUT. Get the icode and push any required reloads
1244 needed for each of them if so. */
1246 #ifdef SECONDARY_INPUT_RELOAD_CLASS
1249 = push_secondary_reload (1, in
, opnum
, optional
, class, inmode
, type
,
1250 &secondary_in_icode
);
1253 #ifdef SECONDARY_OUTPUT_RELOAD_CLASS
1254 if (out
!= 0 && GET_CODE (out
) != SCRATCH
)
1255 secondary_out_reload
1256 = push_secondary_reload (0, out
, opnum
, optional
, class, outmode
,
1257 type
, &secondary_out_icode
);
1260 /* We found no existing reload suitable for re-use.
1261 So add an additional reload. */
1263 #ifdef SECONDARY_MEMORY_NEEDED
1264 /* If a memory location is needed for the copy, make one. */
1265 if (in
!= 0 && GET_CODE (in
) == REG
1266 && REGNO (in
) < FIRST_PSEUDO_REGISTER
1267 && SECONDARY_MEMORY_NEEDED (REGNO_REG_CLASS (REGNO (in
)),
1269 get_secondary_mem (in
, inmode
, opnum
, type
);
1274 reload_out
[i
] = out
;
1275 reload_reg_class
[i
] = class;
1276 reload_inmode
[i
] = inmode
;
1277 reload_outmode
[i
] = outmode
;
1278 reload_reg_rtx
[i
] = 0;
1279 reload_optional
[i
] = optional
;
1280 reload_nongroup
[i
] = 0;
1282 reload_nocombine
[i
] = 0;
1283 reload_in_reg
[i
] = inloc
? *inloc
: 0;
1284 reload_opnum
[i
] = opnum
;
1285 reload_when_needed
[i
] = type
;
1286 reload_secondary_in_reload
[i
] = secondary_in_reload
;
1287 reload_secondary_out_reload
[i
] = secondary_out_reload
;
1288 reload_secondary_in_icode
[i
] = secondary_in_icode
;
1289 reload_secondary_out_icode
[i
] = secondary_out_icode
;
1290 reload_secondary_p
[i
] = 0;
1294 #ifdef SECONDARY_MEMORY_NEEDED
1295 if (out
!= 0 && GET_CODE (out
) == REG
1296 && REGNO (out
) < FIRST_PSEUDO_REGISTER
1297 && SECONDARY_MEMORY_NEEDED (class, REGNO_REG_CLASS (REGNO (out
)),
1299 get_secondary_mem (out
, outmode
, opnum
, type
);
1304 /* We are reusing an existing reload,
1305 but we may have additional information for it.
1306 For example, we may now have both IN and OUT
1307 while the old one may have just one of them. */
1309 /* The modes can be different. If they are, we want to reload in
1310 the larger mode, so that the value is valid for both modes. */
1311 if (inmode
!= VOIDmode
1312 && GET_MODE_SIZE (inmode
) > GET_MODE_SIZE (reload_inmode
[i
]))
1313 reload_inmode
[i
] = inmode
;
1314 if (outmode
!= VOIDmode
1315 && GET_MODE_SIZE (outmode
) > GET_MODE_SIZE (reload_outmode
[i
]))
1316 reload_outmode
[i
] = outmode
;
1320 reload_out
[i
] = out
;
1321 if (reg_class_subset_p (class, reload_reg_class
[i
]))
1322 reload_reg_class
[i
] = class;
1323 reload_optional
[i
] &= optional
;
1324 if (MERGE_TO_OTHER (type
, reload_when_needed
[i
],
1325 opnum
, reload_opnum
[i
]))
1326 reload_when_needed
[i
] = RELOAD_OTHER
;
1327 reload_opnum
[i
] = MIN (reload_opnum
[i
], opnum
);
1330 /* If the ostensible rtx being reload differs from the rtx found
1331 in the location to substitute, this reload is not safe to combine
1332 because we cannot reliably tell whether it appears in the insn. */
1334 if (in
!= 0 && in
!= *inloc
)
1335 reload_nocombine
[i
] = 1;
1338 /* This was replaced by changes in find_reloads_address_1 and the new
1339 function inc_for_reload, which go with a new meaning of reload_inc. */
1341 /* If this is an IN/OUT reload in an insn that sets the CC,
1342 it must be for an autoincrement. It doesn't work to store
1343 the incremented value after the insn because that would clobber the CC.
1344 So we must do the increment of the value reloaded from,
1345 increment it, store it back, then decrement again. */
1346 if (out
!= 0 && sets_cc0_p (PATTERN (this_insn
)))
1350 reload_inc
[i
] = find_inc_amount (PATTERN (this_insn
), in
);
1351 /* If we did not find a nonzero amount-to-increment-by,
1352 that contradicts the belief that IN is being incremented
1353 in an address in this insn. */
1354 if (reload_inc
[i
] == 0)
1359 /* If we will replace IN and OUT with the reload-reg,
1360 record where they are located so that substitution need
1361 not do a tree walk. */
1363 if (replace_reloads
)
1367 register struct replacement
*r
= &replacements
[n_replacements
++];
1369 r
->subreg_loc
= in_subreg_loc
;
1373 if (outloc
!= 0 && outloc
!= inloc
)
1375 register struct replacement
*r
= &replacements
[n_replacements
++];
1378 r
->subreg_loc
= out_subreg_loc
;
1383 /* If this reload is just being introduced and it has both
1384 an incoming quantity and an outgoing quantity that are
1385 supposed to be made to match, see if either one of the two
1386 can serve as the place to reload into.
1388 If one of them is acceptable, set reload_reg_rtx[i]
1391 if (in
!= 0 && out
!= 0 && in
!= out
&& reload_reg_rtx
[i
] == 0)
1393 reload_reg_rtx
[i
] = find_dummy_reload (in
, out
, inloc
, outloc
,
1395 reload_reg_class
[i
], i
,
1396 earlyclobber_operand_p (out
));
1398 /* If the outgoing register already contains the same value
1399 as the incoming one, we can dispense with loading it.
1400 The easiest way to tell the caller that is to give a phony
1401 value for the incoming operand (same as outgoing one). */
1402 if (reload_reg_rtx
[i
] == out
1403 && (GET_CODE (in
) == REG
|| CONSTANT_P (in
))
1404 && 0 != find_equiv_reg (in
, this_insn
, 0, REGNO (out
),
1405 static_reload_reg_p
, i
, inmode
))
1409 /* If this is an input reload and the operand contains a register that
1410 dies in this insn and is used nowhere else, see if it is the right class
1411 to be used for this reload. Use it if so. (This occurs most commonly
1412 in the case of paradoxical SUBREGs and in-out reloads). We cannot do
1413 this if it is also an output reload that mentions the register unless
1414 the output is a SUBREG that clobbers an entire register.
1416 Note that the operand might be one of the spill regs, if it is a
1417 pseudo reg and we are in a block where spilling has not taken place.
1418 But if there is no spilling in this block, that is OK.
1419 An explicitly used hard reg cannot be a spill reg. */
1421 if (reload_reg_rtx
[i
] == 0 && in
!= 0)
1426 for (note
= REG_NOTES (this_insn
); note
; note
= XEXP (note
, 1))
1427 if (REG_NOTE_KIND (note
) == REG_DEAD
1428 && GET_CODE (XEXP (note
, 0)) == REG
1429 && (regno
= REGNO (XEXP (note
, 0))) < FIRST_PSEUDO_REGISTER
1430 && reg_mentioned_p (XEXP (note
, 0), in
)
1431 && ! refers_to_regno_for_reload_p (regno
,
1433 + HARD_REGNO_NREGS (regno
,
1435 PATTERN (this_insn
), inloc
)
1436 /* If this is also an output reload, IN cannot be used as
1437 the reload register if it is set in this insn unless IN
1439 && (out
== 0 || in
== out
1440 || ! hard_reg_set_here_p (regno
,
1442 + HARD_REGNO_NREGS (regno
,
1444 PATTERN (this_insn
)))
1445 /* ??? Why is this code so different from the previous?
1446 Is there any simple coherent way to describe the two together?
1447 What's going on here. */
1449 || (GET_CODE (in
) == SUBREG
1450 && (((GET_MODE_SIZE (GET_MODE (in
)) + (UNITS_PER_WORD
- 1))
1452 == ((GET_MODE_SIZE (GET_MODE (SUBREG_REG (in
)))
1453 + (UNITS_PER_WORD
- 1)) / UNITS_PER_WORD
))))
1454 /* Make sure the operand fits in the reg that dies. */
1455 && GET_MODE_SIZE (inmode
) <= GET_MODE_SIZE (GET_MODE (XEXP (note
, 0)))
1456 && HARD_REGNO_MODE_OK (regno
, inmode
)
1457 && GET_MODE_SIZE (outmode
) <= GET_MODE_SIZE (GET_MODE (XEXP (note
, 0)))
1458 && HARD_REGNO_MODE_OK (regno
, outmode
)
1459 && TEST_HARD_REG_BIT (reg_class_contents
[(int) class], regno
)
1460 && !fixed_regs
[regno
])
1462 reload_reg_rtx
[i
] = gen_rtx_REG (inmode
, regno
);
1468 output_reloadnum
= i
;
1473 /* Record an additional place we must replace a value
1474 for which we have already recorded a reload.
1475 RELOADNUM is the value returned by push_reload
1476 when the reload was recorded.
1477 This is used in insn patterns that use match_dup. */
1480 push_replacement (loc
, reloadnum
, mode
)
1483 enum machine_mode mode
;
1485 if (replace_reloads
)
1487 register struct replacement
*r
= &replacements
[n_replacements
++];
1488 r
->what
= reloadnum
;
1495 /* Transfer all replacements that used to be in reload FROM to be in
1499 transfer_replacements (to
, from
)
1504 for (i
= 0; i
< n_replacements
; i
++)
1505 if (replacements
[i
].what
== from
)
1506 replacements
[i
].what
= to
;
1509 /* Remove all replacements in reload FROM. */
1511 remove_replacements (from
)
1516 for (i
= 0, j
= 0; i
< n_replacements
; i
++)
1518 if (replacements
[i
].what
== from
)
1520 replacements
[j
++] = replacements
[i
];
1524 /* If there is only one output reload, and it is not for an earlyclobber
1525 operand, try to combine it with a (logically unrelated) input reload
1526 to reduce the number of reload registers needed.
1528 This is safe if the input reload does not appear in
1529 the value being output-reloaded, because this implies
1530 it is not needed any more once the original insn completes.
1532 If that doesn't work, see we can use any of the registers that
1533 die in this insn as a reload register. We can if it is of the right
1534 class and does not appear in the value being output-reloaded. */
1540 int output_reload
= -1;
1541 int secondary_out
= -1;
1544 /* Find the output reload; return unless there is exactly one
1545 and that one is mandatory. */
1547 for (i
= 0; i
< n_reloads
; i
++)
1548 if (reload_out
[i
] != 0)
1550 if (output_reload
>= 0)
1555 if (output_reload
< 0 || reload_optional
[output_reload
])
1558 /* An input-output reload isn't combinable. */
1560 if (reload_in
[output_reload
] != 0)
1563 /* If this reload is for an earlyclobber operand, we can't do anything. */
1564 if (earlyclobber_operand_p (reload_out
[output_reload
]))
1567 /* Check each input reload; can we combine it? */
1569 for (i
= 0; i
< n_reloads
; i
++)
1570 if (reload_in
[i
] && ! reload_optional
[i
] && ! reload_nocombine
[i
]
1571 /* Life span of this reload must not extend past main insn. */
1572 && reload_when_needed
[i
] != RELOAD_FOR_OUTPUT_ADDRESS
1573 && reload_when_needed
[i
] != RELOAD_FOR_OUTADDR_ADDRESS
1574 && reload_when_needed
[i
] != RELOAD_OTHER
1575 && (CLASS_MAX_NREGS (reload_reg_class
[i
], reload_inmode
[i
])
1576 == CLASS_MAX_NREGS (reload_reg_class
[output_reload
],
1577 reload_outmode
[output_reload
]))
1578 && reload_inc
[i
] == 0
1579 && reload_reg_rtx
[i
] == 0
1580 #ifdef SECONDARY_MEMORY_NEEDED
1581 /* Don't combine two reloads with different secondary
1582 memory locations. */
1583 && (secondary_memlocs_elim
[(int) reload_outmode
[output_reload
]][reload_opnum
[i
]] == 0
1584 || secondary_memlocs_elim
[(int) reload_outmode
[output_reload
]][reload_opnum
[output_reload
]] == 0
1585 || rtx_equal_p (secondary_memlocs_elim
[(int) reload_outmode
[output_reload
]][reload_opnum
[i
]],
1586 secondary_memlocs_elim
[(int) reload_outmode
[output_reload
]][reload_opnum
[output_reload
]]))
1588 && (SMALL_REGISTER_CLASSES
1589 ? (reload_reg_class
[i
] == reload_reg_class
[output_reload
])
1590 : (reg_class_subset_p (reload_reg_class
[i
],
1591 reload_reg_class
[output_reload
])
1592 || reg_class_subset_p (reload_reg_class
[output_reload
],
1593 reload_reg_class
[i
])))
1594 && (MATCHES (reload_in
[i
], reload_out
[output_reload
])
1595 /* Args reversed because the first arg seems to be
1596 the one that we imagine being modified
1597 while the second is the one that might be affected. */
1598 || (! reg_overlap_mentioned_for_reload_p (reload_out
[output_reload
],
1600 /* However, if the input is a register that appears inside
1601 the output, then we also can't share.
1602 Imagine (set (mem (reg 69)) (plus (reg 69) ...)).
1603 If the same reload reg is used for both reg 69 and the
1604 result to be stored in memory, then that result
1605 will clobber the address of the memory ref. */
1606 && ! (GET_CODE (reload_in
[i
]) == REG
1607 && reg_overlap_mentioned_for_reload_p (reload_in
[i
],
1608 reload_out
[output_reload
]))))
1609 && (reg_class_size
[(int) reload_reg_class
[i
]]
1610 || SMALL_REGISTER_CLASSES
)
1611 /* We will allow making things slightly worse by combining an
1612 input and an output, but no worse than that. */
1613 && (reload_when_needed
[i
] == RELOAD_FOR_INPUT
1614 || reload_when_needed
[i
] == RELOAD_FOR_OUTPUT
))
1618 /* We have found a reload to combine with! */
1619 reload_out
[i
] = reload_out
[output_reload
];
1620 reload_outmode
[i
] = reload_outmode
[output_reload
];
1621 /* Mark the old output reload as inoperative. */
1622 reload_out
[output_reload
] = 0;
1623 /* The combined reload is needed for the entire insn. */
1624 reload_when_needed
[i
] = RELOAD_OTHER
;
1625 /* If the output reload had a secondary reload, copy it. */
1626 if (reload_secondary_out_reload
[output_reload
] != -1)
1628 reload_secondary_out_reload
[i
]
1629 = reload_secondary_out_reload
[output_reload
];
1630 reload_secondary_out_icode
[i
]
1631 = reload_secondary_out_icode
[output_reload
];
1634 #ifdef SECONDARY_MEMORY_NEEDED
1635 /* Copy any secondary MEM. */
1636 if (secondary_memlocs_elim
[(int) reload_outmode
[output_reload
]][reload_opnum
[output_reload
]] != 0)
1637 secondary_memlocs_elim
[(int) reload_outmode
[output_reload
]][reload_opnum
[i
]]
1638 = secondary_memlocs_elim
[(int) reload_outmode
[output_reload
]][reload_opnum
[output_reload
]];
1640 /* If required, minimize the register class. */
1641 if (reg_class_subset_p (reload_reg_class
[output_reload
],
1642 reload_reg_class
[i
]))
1643 reload_reg_class
[i
] = reload_reg_class
[output_reload
];
1645 /* Transfer all replacements from the old reload to the combined. */
1646 for (j
= 0; j
< n_replacements
; j
++)
1647 if (replacements
[j
].what
== output_reload
)
1648 replacements
[j
].what
= i
;
1653 /* If this insn has only one operand that is modified or written (assumed
1654 to be the first), it must be the one corresponding to this reload. It
1655 is safe to use anything that dies in this insn for that output provided
1656 that it does not occur in the output (we already know it isn't an
1657 earlyclobber. If this is an asm insn, give up. */
1659 if (INSN_CODE (this_insn
) == -1)
1662 for (i
= 1; i
< insn_n_operands
[INSN_CODE (this_insn
)]; i
++)
1663 if (insn_operand_constraint
[INSN_CODE (this_insn
)][i
][0] == '='
1664 || insn_operand_constraint
[INSN_CODE (this_insn
)][i
][0] == '+')
1667 /* See if some hard register that dies in this insn and is not used in
1668 the output is the right class. Only works if the register we pick
1669 up can fully hold our output reload. */
1670 for (note
= REG_NOTES (this_insn
); note
; note
= XEXP (note
, 1))
1671 if (REG_NOTE_KIND (note
) == REG_DEAD
1672 && GET_CODE (XEXP (note
, 0)) == REG
1673 && ! reg_overlap_mentioned_for_reload_p (XEXP (note
, 0),
1674 reload_out
[output_reload
])
1675 && REGNO (XEXP (note
, 0)) < FIRST_PSEUDO_REGISTER
1676 && HARD_REGNO_MODE_OK (REGNO (XEXP (note
, 0)), reload_outmode
[output_reload
])
1677 && TEST_HARD_REG_BIT (reg_class_contents
[(int) reload_reg_class
[output_reload
]],
1678 REGNO (XEXP (note
, 0)))
1679 && (HARD_REGNO_NREGS (REGNO (XEXP (note
, 0)), reload_outmode
[output_reload
])
1680 <= HARD_REGNO_NREGS (REGNO (XEXP (note
, 0)), GET_MODE (XEXP (note
, 0))))
1681 /* Ensure that a secondary or tertiary reload for this output
1682 won't want this register. */
1683 && ((secondary_out
= reload_secondary_out_reload
[output_reload
]) == -1
1684 || (! (TEST_HARD_REG_BIT
1685 (reg_class_contents
[(int) reload_reg_class
[secondary_out
]],
1686 REGNO (XEXP (note
, 0))))
1687 && ((secondary_out
= reload_secondary_out_reload
[secondary_out
]) == -1
1688 || ! (TEST_HARD_REG_BIT
1689 (reg_class_contents
[(int) reload_reg_class
[secondary_out
]],
1690 REGNO (XEXP (note
, 0)))))))
1691 && ! fixed_regs
[REGNO (XEXP (note
, 0))])
1693 reload_reg_rtx
[output_reload
]
1694 = gen_rtx_REG (reload_outmode
[output_reload
],
1695 REGNO (XEXP (note
, 0)));
1700 /* Try to find a reload register for an in-out reload (expressions IN and OUT).
1701 See if one of IN and OUT is a register that may be used;
1702 this is desirable since a spill-register won't be needed.
1703 If so, return the register rtx that proves acceptable.
1705 INLOC and OUTLOC are locations where IN and OUT appear in the insn.
1706 CLASS is the register class required for the reload.
1708 If FOR_REAL is >= 0, it is the number of the reload,
1709 and in some cases when it can be discovered that OUT doesn't need
1710 to be computed, clear out reload_out[FOR_REAL].
1712 If FOR_REAL is -1, this should not be done, because this call
1713 is just to see if a register can be found, not to find and install it.
1715 EARLYCLOBBER is non-zero if OUT is an earlyclobber operand. This
1716 puts an additional constraint on being able to use IN for OUT since
1717 IN must not appear elsewhere in the insn (it is assumed that IN itself
1718 is safe from the earlyclobber). */
1721 find_dummy_reload (real_in
, real_out
, inloc
, outloc
,
1722 inmode
, outmode
, class, for_real
, earlyclobber
)
1723 rtx real_in
, real_out
;
1724 rtx
*inloc
, *outloc
;
1725 enum machine_mode inmode
, outmode
;
1726 enum reg_class
class;
1736 /* If operands exceed a word, we can't use either of them
1737 unless they have the same size. */
1738 if (GET_MODE_SIZE (outmode
) != GET_MODE_SIZE (inmode
)
1739 && (GET_MODE_SIZE (outmode
) > UNITS_PER_WORD
1740 || GET_MODE_SIZE (inmode
) > UNITS_PER_WORD
))
1743 /* Find the inside of any subregs. */
1744 while (GET_CODE (out
) == SUBREG
)
1746 out_offset
= SUBREG_WORD (out
);
1747 out
= SUBREG_REG (out
);
1749 while (GET_CODE (in
) == SUBREG
)
1751 in_offset
= SUBREG_WORD (in
);
1752 in
= SUBREG_REG (in
);
1755 /* Narrow down the reg class, the same way push_reload will;
1756 otherwise we might find a dummy now, but push_reload won't. */
1757 class = PREFERRED_RELOAD_CLASS (in
, class);
1759 /* See if OUT will do. */
1760 if (GET_CODE (out
) == REG
1761 && REGNO (out
) < FIRST_PSEUDO_REGISTER
)
1763 register int regno
= REGNO (out
) + out_offset
;
1764 int nwords
= HARD_REGNO_NREGS (regno
, outmode
);
1767 /* When we consider whether the insn uses OUT,
1768 ignore references within IN. They don't prevent us
1769 from copying IN into OUT, because those refs would
1770 move into the insn that reloads IN.
1772 However, we only ignore IN in its role as this reload.
1773 If the insn uses IN elsewhere and it contains OUT,
1774 that counts. We can't be sure it's the "same" operand
1775 so it might not go through this reload. */
1777 *inloc
= const0_rtx
;
1779 if (regno
< FIRST_PSEUDO_REGISTER
1780 /* A fixed reg that can overlap other regs better not be used
1781 for reloading in any way. */
1782 #ifdef OVERLAPPING_REGNO_P
1783 && ! (fixed_regs
[regno
] && OVERLAPPING_REGNO_P (regno
))
1785 && ! refers_to_regno_for_reload_p (regno
, regno
+ nwords
,
1786 PATTERN (this_insn
), outloc
))
1789 for (i
= 0; i
< nwords
; i
++)
1790 if (! TEST_HARD_REG_BIT (reg_class_contents
[(int) class],
1796 if (GET_CODE (real_out
) == REG
)
1799 value
= gen_rtx_REG (outmode
, regno
);
1806 /* Consider using IN if OUT was not acceptable
1807 or if OUT dies in this insn (like the quotient in a divmod insn).
1808 We can't use IN unless it is dies in this insn,
1809 which means we must know accurately which hard regs are live.
1810 Also, the result can't go in IN if IN is used within OUT,
1811 or if OUT is an earlyclobber and IN appears elsewhere in the insn. */
1812 if (hard_regs_live_known
1813 && GET_CODE (in
) == REG
1814 && REGNO (in
) < FIRST_PSEUDO_REGISTER
1816 || find_reg_note (this_insn
, REG_UNUSED
, real_out
))
1817 && find_reg_note (this_insn
, REG_DEAD
, real_in
)
1818 && !fixed_regs
[REGNO (in
)]
1819 && HARD_REGNO_MODE_OK (REGNO (in
),
1820 /* The only case where out and real_out might
1821 have different modes is where real_out
1822 is a subreg, and in that case, out
1824 (GET_MODE (out
) != VOIDmode
1825 ? GET_MODE (out
) : outmode
)))
1827 register int regno
= REGNO (in
) + in_offset
;
1828 int nwords
= HARD_REGNO_NREGS (regno
, inmode
);
1830 if (! refers_to_regno_for_reload_p (regno
, regno
+ nwords
, out
, NULL_PTR
)
1831 && ! hard_reg_set_here_p (regno
, regno
+ nwords
,
1832 PATTERN (this_insn
))
1834 || ! refers_to_regno_for_reload_p (regno
, regno
+ nwords
,
1835 PATTERN (this_insn
), inloc
)))
1838 for (i
= 0; i
< nwords
; i
++)
1839 if (! TEST_HARD_REG_BIT (reg_class_contents
[(int) class],
1845 /* If we were going to use OUT as the reload reg
1846 and changed our mind, it means OUT is a dummy that
1847 dies here. So don't bother copying value to it. */
1848 if (for_real
>= 0 && value
== real_out
)
1849 reload_out
[for_real
] = 0;
1850 if (GET_CODE (real_in
) == REG
)
1853 value
= gen_rtx_REG (inmode
, regno
);
1861 /* This page contains subroutines used mainly for determining
1862 whether the IN or an OUT of a reload can serve as the
1865 /* Return 1 if X is an operand of an insn that is being earlyclobbered. */
1868 earlyclobber_operand_p (x
)
1873 for (i
= 0; i
< n_earlyclobbers
; i
++)
1874 if (reload_earlyclobbers
[i
] == x
)
1880 /* Return 1 if expression X alters a hard reg in the range
1881 from BEG_REGNO (inclusive) to END_REGNO (exclusive),
1882 either explicitly or in the guise of a pseudo-reg allocated to REGNO.
1883 X should be the body of an instruction. */
1886 hard_reg_set_here_p (beg_regno
, end_regno
, x
)
1887 register int beg_regno
, end_regno
;
1890 if (GET_CODE (x
) == SET
|| GET_CODE (x
) == CLOBBER
)
1892 register rtx op0
= SET_DEST (x
);
1893 while (GET_CODE (op0
) == SUBREG
)
1894 op0
= SUBREG_REG (op0
);
1895 if (GET_CODE (op0
) == REG
)
1897 register int r
= REGNO (op0
);
1898 /* See if this reg overlaps range under consideration. */
1900 && r
+ HARD_REGNO_NREGS (r
, GET_MODE (op0
)) > beg_regno
)
1904 else if (GET_CODE (x
) == PARALLEL
)
1906 register int i
= XVECLEN (x
, 0) - 1;
1908 if (hard_reg_set_here_p (beg_regno
, end_regno
, XVECEXP (x
, 0, i
)))
1915 /* Return 1 if ADDR is a valid memory address for mode MODE,
1916 and check that each pseudo reg has the proper kind of
1920 strict_memory_address_p (mode
, addr
)
1921 enum machine_mode mode
;
1924 GO_IF_LEGITIMATE_ADDRESS (mode
, addr
, win
);
1931 /* Like rtx_equal_p except that it allows a REG and a SUBREG to match
1932 if they are the same hard reg, and has special hacks for
1933 autoincrement and autodecrement.
1934 This is specifically intended for find_reloads to use
1935 in determining whether two operands match.
1936 X is the operand whose number is the lower of the two.
1938 The value is 2 if Y contains a pre-increment that matches
1939 a non-incrementing address in X. */
1941 /* ??? To be completely correct, we should arrange to pass
1942 for X the output operand and for Y the input operand.
1943 For now, we assume that the output operand has the lower number
1944 because that is natural in (SET output (... input ...)). */
1947 operands_match_p (x
, y
)
1951 register RTX_CODE code
= GET_CODE (x
);
1957 if ((code
== REG
|| (code
== SUBREG
&& GET_CODE (SUBREG_REG (x
)) == REG
))
1958 && (GET_CODE (y
) == REG
|| (GET_CODE (y
) == SUBREG
1959 && GET_CODE (SUBREG_REG (y
)) == REG
)))
1965 i
= REGNO (SUBREG_REG (x
));
1966 if (i
>= FIRST_PSEUDO_REGISTER
)
1968 i
+= SUBREG_WORD (x
);
1973 if (GET_CODE (y
) == SUBREG
)
1975 j
= REGNO (SUBREG_REG (y
));
1976 if (j
>= FIRST_PSEUDO_REGISTER
)
1978 j
+= SUBREG_WORD (y
);
1983 /* On a WORDS_BIG_ENDIAN machine, point to the last register of a
1984 multiple hard register group, so that for example (reg:DI 0) and
1985 (reg:SI 1) will be considered the same register. */
1986 if (WORDS_BIG_ENDIAN
&& GET_MODE_SIZE (GET_MODE (x
)) > UNITS_PER_WORD
1987 && i
< FIRST_PSEUDO_REGISTER
)
1988 i
+= (GET_MODE_SIZE (GET_MODE (x
)) / UNITS_PER_WORD
) - 1;
1989 if (WORDS_BIG_ENDIAN
&& GET_MODE_SIZE (GET_MODE (y
)) > UNITS_PER_WORD
1990 && j
< FIRST_PSEUDO_REGISTER
)
1991 j
+= (GET_MODE_SIZE (GET_MODE (y
)) / UNITS_PER_WORD
) - 1;
1995 /* If two operands must match, because they are really a single
1996 operand of an assembler insn, then two postincrements are invalid
1997 because the assembler insn would increment only once.
1998 On the other hand, an postincrement matches ordinary indexing
1999 if the postincrement is the output operand. */
2000 if (code
== POST_DEC
|| code
== POST_INC
)
2001 return operands_match_p (XEXP (x
, 0), y
);
2002 /* Two preincrements are invalid
2003 because the assembler insn would increment only once.
2004 On the other hand, an preincrement matches ordinary indexing
2005 if the preincrement is the input operand.
2006 In this case, return 2, since some callers need to do special
2007 things when this happens. */
2008 if (GET_CODE (y
) == PRE_DEC
|| GET_CODE (y
) == PRE_INC
)
2009 return operands_match_p (x
, XEXP (y
, 0)) ? 2 : 0;
2013 /* Now we have disposed of all the cases
2014 in which different rtx codes can match. */
2015 if (code
!= GET_CODE (y
))
2017 if (code
== LABEL_REF
)
2018 return XEXP (x
, 0) == XEXP (y
, 0);
2019 if (code
== SYMBOL_REF
)
2020 return XSTR (x
, 0) == XSTR (y
, 0);
2022 /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent. */
2024 if (GET_MODE (x
) != GET_MODE (y
))
2027 /* Compare the elements. If any pair of corresponding elements
2028 fail to match, return 0 for the whole things. */
2031 fmt
= GET_RTX_FORMAT (code
);
2032 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
2038 if (XWINT (x
, i
) != XWINT (y
, i
))
2043 if (XINT (x
, i
) != XINT (y
, i
))
2048 val
= operands_match_p (XEXP (x
, i
), XEXP (y
, i
));
2051 /* If any subexpression returns 2,
2052 we should return 2 if we are successful. */
2060 /* It is believed that rtx's at this level will never
2061 contain anything but integers and other rtx's,
2062 except for within LABEL_REFs and SYMBOL_REFs. */
2067 return 1 + success_2
;
2070 /* Return the number of times character C occurs in string S. */
2073 n_occurrences (c
, s
)
2083 /* Describe the range of registers or memory referenced by X.
2084 If X is a register, set REG_FLAG and put the first register
2085 number into START and the last plus one into END.
2086 If X is a memory reference, put a base address into BASE
2087 and a range of integer offsets into START and END.
2088 If X is pushing on the stack, we can assume it causes no trouble,
2089 so we set the SAFE field. */
2091 static struct decomposition
2095 struct decomposition val
;
2101 if (GET_CODE (x
) == MEM
)
2103 rtx base
, offset
= 0;
2104 rtx addr
= XEXP (x
, 0);
2106 if (GET_CODE (addr
) == PRE_DEC
|| GET_CODE (addr
) == PRE_INC
2107 || GET_CODE (addr
) == POST_DEC
|| GET_CODE (addr
) == POST_INC
)
2109 val
.base
= XEXP (addr
, 0);
2110 val
.start
= - GET_MODE_SIZE (GET_MODE (x
));
2111 val
.end
= GET_MODE_SIZE (GET_MODE (x
));
2112 val
.safe
= REGNO (val
.base
) == STACK_POINTER_REGNUM
;
2116 if (GET_CODE (addr
) == CONST
)
2118 addr
= XEXP (addr
, 0);
2121 if (GET_CODE (addr
) == PLUS
)
2123 if (CONSTANT_P (XEXP (addr
, 0)))
2125 base
= XEXP (addr
, 1);
2126 offset
= XEXP (addr
, 0);
2128 else if (CONSTANT_P (XEXP (addr
, 1)))
2130 base
= XEXP (addr
, 0);
2131 offset
= XEXP (addr
, 1);
2138 offset
= const0_rtx
;
2140 if (GET_CODE (offset
) == CONST
)
2141 offset
= XEXP (offset
, 0);
2142 if (GET_CODE (offset
) == PLUS
)
2144 if (GET_CODE (XEXP (offset
, 0)) == CONST_INT
)
2146 base
= gen_rtx_PLUS (GET_MODE (base
), base
, XEXP (offset
, 1));
2147 offset
= XEXP (offset
, 0);
2149 else if (GET_CODE (XEXP (offset
, 1)) == CONST_INT
)
2151 base
= gen_rtx_PLUS (GET_MODE (base
), base
, XEXP (offset
, 0));
2152 offset
= XEXP (offset
, 1);
2156 base
= gen_rtx_PLUS (GET_MODE (base
), base
, offset
);
2157 offset
= const0_rtx
;
2160 else if (GET_CODE (offset
) != CONST_INT
)
2162 base
= gen_rtx_PLUS (GET_MODE (base
), base
, offset
);
2163 offset
= const0_rtx
;
2166 if (all_const
&& GET_CODE (base
) == PLUS
)
2167 base
= gen_rtx_CONST (GET_MODE (base
), base
);
2169 if (GET_CODE (offset
) != CONST_INT
)
2172 val
.start
= INTVAL (offset
);
2173 val
.end
= val
.start
+ GET_MODE_SIZE (GET_MODE (x
));
2177 else if (GET_CODE (x
) == REG
)
2180 val
.start
= true_regnum (x
);
2183 /* A pseudo with no hard reg. */
2184 val
.start
= REGNO (x
);
2185 val
.end
= val
.start
+ 1;
2189 val
.end
= val
.start
+ HARD_REGNO_NREGS (val
.start
, GET_MODE (x
));
2191 else if (GET_CODE (x
) == SUBREG
)
2193 if (GET_CODE (SUBREG_REG (x
)) != REG
)
2194 /* This could be more precise, but it's good enough. */
2195 return decompose (SUBREG_REG (x
));
2197 val
.start
= true_regnum (x
);
2199 return decompose (SUBREG_REG (x
));
2202 val
.end
= val
.start
+ HARD_REGNO_NREGS (val
.start
, GET_MODE (x
));
2204 else if (CONSTANT_P (x
)
2205 /* This hasn't been assigned yet, so it can't conflict yet. */
2206 || GET_CODE (x
) == SCRATCH
)
2213 /* Return 1 if altering Y will not modify the value of X.
2214 Y is also described by YDATA, which should be decompose (Y). */
2217 immune_p (x
, y
, ydata
)
2219 struct decomposition ydata
;
2221 struct decomposition xdata
;
2224 return !refers_to_regno_for_reload_p (ydata
.start
, ydata
.end
, x
, NULL_PTR
);
2228 if (GET_CODE (y
) != MEM
)
2230 /* If Y is memory and X is not, Y can't affect X. */
2231 if (GET_CODE (x
) != MEM
)
2234 xdata
= decompose (x
);
2236 if (! rtx_equal_p (xdata
.base
, ydata
.base
))
2238 /* If bases are distinct symbolic constants, there is no overlap. */
2239 if (CONSTANT_P (xdata
.base
) && CONSTANT_P (ydata
.base
))
2241 /* Constants and stack slots never overlap. */
2242 if (CONSTANT_P (xdata
.base
)
2243 && (ydata
.base
== frame_pointer_rtx
2244 || ydata
.base
== hard_frame_pointer_rtx
2245 || ydata
.base
== stack_pointer_rtx
))
2247 if (CONSTANT_P (ydata
.base
)
2248 && (xdata
.base
== frame_pointer_rtx
2249 || xdata
.base
== hard_frame_pointer_rtx
2250 || xdata
.base
== stack_pointer_rtx
))
2252 /* If either base is variable, we don't know anything. */
2257 return (xdata
.start
>= ydata
.end
|| ydata
.start
>= xdata
.end
);
2260 /* Similar, but calls decompose. */
2263 safe_from_earlyclobber (op
, clobber
)
2266 struct decomposition early_data
;
2268 early_data
= decompose (clobber
);
2269 return immune_p (op
, clobber
, early_data
);
2272 /* Main entry point of this file: search the body of INSN
2273 for values that need reloading and record them with push_reload.
2274 REPLACE nonzero means record also where the values occur
2275 so that subst_reloads can be used.
2277 IND_LEVELS says how many levels of indirection are supported by this
2278 machine; a value of zero means that a memory reference is not a valid
2281 LIVE_KNOWN says we have valid information about which hard
2282 regs are live at each point in the program; this is true when
2283 we are called from global_alloc but false when stupid register
2284 allocation has been done.
2286 RELOAD_REG_P if nonzero is a vector indexed by hard reg number
2287 which is nonnegative if the reg has been commandeered for reloading into.
2288 It is copied into STATIC_RELOAD_REG_P and referenced from there
2289 by various subroutines. */
2292 find_reloads (insn
, replace
, ind_levels
, live_known
, reload_reg_p
)
2294 int replace
, ind_levels
;
2296 short *reload_reg_p
;
2298 #ifdef REGISTER_CONSTRAINTS
2300 register int insn_code_number
;
2303 /* These are the constraints for the insn. We don't change them. */
2304 char *constraints1
[MAX_RECOG_OPERANDS
];
2305 /* These start out as the constraints for the insn
2306 and they are chewed up as we consider alternatives. */
2307 char *constraints
[MAX_RECOG_OPERANDS
];
2308 /* These are the preferred classes for an operand, or NO_REGS if it isn't
2310 enum reg_class preferred_class
[MAX_RECOG_OPERANDS
];
2311 char pref_or_nothing
[MAX_RECOG_OPERANDS
];
2312 /* Nonzero for a MEM operand whose entire address needs a reload. */
2313 int address_reloaded
[MAX_RECOG_OPERANDS
];
2314 /* Value of enum reload_type to use for operand. */
2315 enum reload_type operand_type
[MAX_RECOG_OPERANDS
];
2316 /* Value of enum reload_type to use within address of operand. */
2317 enum reload_type address_type
[MAX_RECOG_OPERANDS
];
2318 /* Save the usage of each operand. */
2319 enum reload_usage
{ RELOAD_READ
, RELOAD_READ_WRITE
, RELOAD_WRITE
} modified
[MAX_RECOG_OPERANDS
];
2320 int no_input_reloads
= 0, no_output_reloads
= 0;
2322 int this_alternative
[MAX_RECOG_OPERANDS
];
2323 char this_alternative_win
[MAX_RECOG_OPERANDS
];
2324 char this_alternative_offmemok
[MAX_RECOG_OPERANDS
];
2325 char this_alternative_earlyclobber
[MAX_RECOG_OPERANDS
];
2326 int this_alternative_matches
[MAX_RECOG_OPERANDS
];
2328 int goal_alternative
[MAX_RECOG_OPERANDS
];
2329 int this_alternative_number
;
2330 int goal_alternative_number
;
2331 int operand_reloadnum
[MAX_RECOG_OPERANDS
];
2332 int goal_alternative_matches
[MAX_RECOG_OPERANDS
];
2333 int goal_alternative_matched
[MAX_RECOG_OPERANDS
];
2334 char goal_alternative_win
[MAX_RECOG_OPERANDS
];
2335 char goal_alternative_offmemok
[MAX_RECOG_OPERANDS
];
2336 char goal_alternative_earlyclobber
[MAX_RECOG_OPERANDS
];
2337 int goal_alternative_swapped
;
2341 char operands_match
[MAX_RECOG_OPERANDS
][MAX_RECOG_OPERANDS
];
2342 rtx substed_operand
[MAX_RECOG_OPERANDS
];
2343 rtx body
= PATTERN (insn
);
2344 rtx set
= single_set (insn
);
2345 int goal_earlyclobber
, this_earlyclobber
;
2346 enum machine_mode operand_mode
[MAX_RECOG_OPERANDS
];
2349 this_insn_is_asm
= 0; /* Tentative. */
2353 n_earlyclobbers
= 0;
2354 replace_reloads
= replace
;
2355 hard_regs_live_known
= live_known
;
2356 static_reload_reg_p
= reload_reg_p
;
2358 /* JUMP_INSNs and CALL_INSNs are not allowed to have any output reloads;
2359 neither are insns that SET cc0. Insns that use CC0 are not allowed
2360 to have any input reloads. */
2361 if (GET_CODE (insn
) == JUMP_INSN
|| GET_CODE (insn
) == CALL_INSN
)
2362 no_output_reloads
= 1;
2365 if (reg_referenced_p (cc0_rtx
, PATTERN (insn
)))
2366 no_input_reloads
= 1;
2367 if (reg_set_p (cc0_rtx
, PATTERN (insn
)))
2368 no_output_reloads
= 1;
2371 #ifdef SECONDARY_MEMORY_NEEDED
2372 /* The eliminated forms of any secondary memory locations are per-insn, so
2373 clear them out here. */
2375 bzero ((char *) secondary_memlocs_elim
, sizeof secondary_memlocs_elim
);
2378 /* Find what kind of insn this is. NOPERANDS gets number of operands.
2379 Make OPERANDS point to a vector of operand values.
2380 Make OPERAND_LOCS point to a vector of pointers to
2381 where the operands were found.
2382 Fill CONSTRAINTS and CONSTRAINTS1 with pointers to the
2383 constraint-strings for this insn.
2384 Return if the insn needs no reload processing. */
2386 switch (GET_CODE (body
))
2396 /* Dispose quickly of (set (reg..) (reg..)) if both have hard regs and it
2397 is cheap to move between them. If it is not, there may not be an insn
2398 to do the copy, so we may need a reload. */
2399 if (GET_CODE (SET_DEST (body
)) == REG
2400 && REGNO (SET_DEST (body
)) < FIRST_PSEUDO_REGISTER
2401 && GET_CODE (SET_SRC (body
)) == REG
2402 && REGNO (SET_SRC (body
)) < FIRST_PSEUDO_REGISTER
2403 && REGISTER_MOVE_COST (REGNO_REG_CLASS (REGNO (SET_SRC (body
))),
2404 REGNO_REG_CLASS (REGNO (SET_DEST (body
)))) == 2)
2408 reload_n_operands
= noperands
= asm_noperands (body
);
2411 /* This insn is an `asm' with operands. */
2413 insn_code_number
= -1;
2414 this_insn_is_asm
= 1;
2416 /* expand_asm_operands makes sure there aren't too many operands. */
2417 if (noperands
> MAX_RECOG_OPERANDS
)
2420 /* Now get the operand values and constraints out of the insn. */
2422 decode_asm_operands (body
, recog_operand
, recog_operand_loc
,
2423 constraints
, operand_mode
);
2426 bcopy ((char *) constraints
, (char *) constraints1
,
2427 noperands
* sizeof (char *));
2428 n_alternatives
= n_occurrences (',', constraints
[0]) + 1;
2429 for (i
= 1; i
< noperands
; i
++)
2430 if (n_alternatives
!= n_occurrences (',', constraints
[i
]) + 1)
2432 error_for_asm (insn
, "operand constraints differ in number of alternatives");
2433 /* Avoid further trouble with this insn. */
2434 PATTERN (insn
) = gen_rtx_USE (VOIDmode
, const0_rtx
);
2443 /* Ordinary insn: recognize it, get the operands via insn_extract
2444 and get the constraints. */
2446 insn_code_number
= recog_memoized (insn
);
2447 if (insn_code_number
< 0)
2448 fatal_insn_not_found (insn
);
2450 reload_n_operands
= noperands
= insn_n_operands
[insn_code_number
];
2451 n_alternatives
= insn_n_alternatives
[insn_code_number
];
2452 /* Just return "no reloads" if insn has no operands with constraints. */
2453 if (n_alternatives
== 0)
2455 insn_extract (insn
);
2456 for (i
= 0; i
< noperands
; i
++)
2458 constraints
[i
] = constraints1
[i
]
2459 = insn_operand_constraint
[insn_code_number
][i
];
2460 operand_mode
[i
] = insn_operand_mode
[insn_code_number
][i
];
2469 /* If we will need to know, later, whether some pair of operands
2470 are the same, we must compare them now and save the result.
2471 Reloading the base and index registers will clobber them
2472 and afterward they will fail to match. */
2474 for (i
= 0; i
< noperands
; i
++)
2479 substed_operand
[i
] = recog_operand
[i
];
2482 modified
[i
] = RELOAD_READ
;
2484 /* Scan this operand's constraint to see if it is an output operand,
2485 an in-out operand, is commutative, or should match another. */
2490 modified
[i
] = RELOAD_WRITE
;
2492 modified
[i
] = RELOAD_READ_WRITE
;
2495 /* The last operand should not be marked commutative. */
2496 if (i
== noperands
- 1)
2498 if (this_insn_is_asm
)
2499 warning_for_asm (this_insn
,
2500 "`%%' constraint used with last operand");
2507 else if (c
>= '0' && c
<= '9')
2510 operands_match
[c
][i
]
2511 = operands_match_p (recog_operand
[c
], recog_operand
[i
]);
2513 /* An operand may not match itself. */
2516 if (this_insn_is_asm
)
2517 warning_for_asm (this_insn
,
2518 "operand %d has constraint %d", i
, c
);
2523 /* If C can be commuted with C+1, and C might need to match I,
2524 then C+1 might also need to match I. */
2525 if (commutative
>= 0)
2527 if (c
== commutative
|| c
== commutative
+ 1)
2529 int other
= c
+ (c
== commutative
? 1 : -1);
2530 operands_match
[other
][i
]
2531 = operands_match_p (recog_operand
[other
], recog_operand
[i
]);
2533 if (i
== commutative
|| i
== commutative
+ 1)
2535 int other
= i
+ (i
== commutative
? 1 : -1);
2536 operands_match
[c
][other
]
2537 = operands_match_p (recog_operand
[c
], recog_operand
[other
]);
2539 /* Note that C is supposed to be less than I.
2540 No need to consider altering both C and I because in
2541 that case we would alter one into the other. */
2547 /* Examine each operand that is a memory reference or memory address
2548 and reload parts of the addresses into index registers.
2549 Also here any references to pseudo regs that didn't get hard regs
2550 but are equivalent to constants get replaced in the insn itself
2551 with those constants. Nobody will ever see them again.
2553 Finally, set up the preferred classes of each operand. */
2555 for (i
= 0; i
< noperands
; i
++)
2557 register RTX_CODE code
= GET_CODE (recog_operand
[i
]);
2559 address_reloaded
[i
] = 0;
2560 operand_type
[i
] = (modified
[i
] == RELOAD_READ
? RELOAD_FOR_INPUT
2561 : modified
[i
] == RELOAD_WRITE
? RELOAD_FOR_OUTPUT
2564 = (modified
[i
] == RELOAD_READ
? RELOAD_FOR_INPUT_ADDRESS
2565 : modified
[i
] == RELOAD_WRITE
? RELOAD_FOR_OUTPUT_ADDRESS
2568 if (*constraints
[i
] == 0)
2569 /* Ignore things like match_operator operands. */
2571 else if (constraints
[i
][0] == 'p')
2573 find_reloads_address (VOIDmode
, NULL_PTR
,
2574 recog_operand
[i
], recog_operand_loc
[i
],
2575 i
, operand_type
[i
], ind_levels
, insn
);
2577 /* If we now have a simple operand where we used to have a
2578 PLUS or MULT, re-recognize and try again. */
2579 if ((GET_RTX_CLASS (GET_CODE (*recog_operand_loc
[i
])) == 'o'
2580 || GET_CODE (*recog_operand_loc
[i
]) == SUBREG
)
2581 && (GET_CODE (recog_operand
[i
]) == MULT
2582 || GET_CODE (recog_operand
[i
]) == PLUS
))
2584 INSN_CODE (insn
) = -1;
2585 find_reloads (insn
, replace
, ind_levels
, live_known
,
2590 substed_operand
[i
] = recog_operand
[i
] = *recog_operand_loc
[i
];
2592 else if (code
== MEM
)
2594 if (find_reloads_address (GET_MODE (recog_operand
[i
]),
2595 recog_operand_loc
[i
],
2596 XEXP (recog_operand
[i
], 0),
2597 &XEXP (recog_operand
[i
], 0),
2598 i
, address_type
[i
], ind_levels
, insn
))
2599 address_reloaded
[i
] = 1;
2600 substed_operand
[i
] = recog_operand
[i
] = *recog_operand_loc
[i
];
2602 else if (code
== SUBREG
)
2604 rtx reg
= SUBREG_REG (recog_operand
[i
]);
2606 = find_reloads_toplev (recog_operand
[i
], i
, address_type
[i
],
2609 && &SET_DEST (set
) == recog_operand_loc
[i
]);
2611 /* If we made a MEM to load (a part of) the stackslot of a pseudo
2612 that didn't get a hard register, emit a USE with a REG_EQUAL
2613 note in front so that we might inherit a previous, possibly
2616 if (GET_CODE (op
) == MEM
2617 && GET_CODE (reg
) == REG
2618 && (GET_MODE_SIZE (GET_MODE (reg
))
2619 >= GET_MODE_SIZE (GET_MODE (op
))))
2620 REG_NOTES (emit_insn_before (gen_rtx_USE (VOIDmode
, reg
), insn
))
2621 = gen_rtx_EXPR_LIST (REG_EQUAL
,
2622 reg_equiv_memory_loc
[REGNO (reg
)], NULL_RTX
);
2624 substed_operand
[i
] = recog_operand
[i
] = *recog_operand_loc
[i
] = op
;
2626 else if (code
== PLUS
|| GET_RTX_CLASS (code
) == '1')
2627 /* We can get a PLUS as an "operand" as a result of register
2628 elimination. See eliminate_regs and gen_reload. We handle
2629 a unary operator by reloading the operand. */
2630 substed_operand
[i
] = recog_operand
[i
] = *recog_operand_loc
[i
]
2631 = find_reloads_toplev (recog_operand
[i
], i
, address_type
[i
],
2633 else if (code
== REG
)
2635 /* This is equivalent to calling find_reloads_toplev.
2636 The code is duplicated for speed.
2637 When we find a pseudo always equivalent to a constant,
2638 we replace it by the constant. We must be sure, however,
2639 that we don't try to replace it in the insn in which it
2641 register int regno
= REGNO (recog_operand
[i
]);
2642 if (reg_equiv_constant
[regno
] != 0
2643 && (set
== 0 || &SET_DEST (set
) != recog_operand_loc
[i
]))
2645 /* Record the existing mode so that the check if constants are
2646 allowed will work when operand_mode isn't specified. */
2648 if (operand_mode
[i
] == VOIDmode
)
2649 operand_mode
[i
] = GET_MODE (recog_operand
[i
]);
2651 substed_operand
[i
] = recog_operand
[i
]
2652 = reg_equiv_constant
[regno
];
2654 #if 0 /* This might screw code in reload1.c to delete prior output-reload
2655 that feeds this insn. */
2656 if (reg_equiv_mem
[regno
] != 0)
2657 substed_operand
[i
] = recog_operand
[i
]
2658 = reg_equiv_mem
[regno
];
2660 if (reg_equiv_address
[regno
] != 0)
2662 /* If reg_equiv_address is not a constant address, copy it,
2663 since it may be shared. */
2664 /* We must rerun eliminate_regs, in case the elimination
2665 offsets have changed. */
2666 rtx address
= XEXP (eliminate_regs (reg_equiv_memory_loc
[regno
],
2670 if (rtx_varies_p (address
))
2671 address
= copy_rtx (address
);
2673 /* Emit a USE that shows what register is being used/modified. */
2674 REG_NOTES (emit_insn_before (gen_rtx_USE (VOIDmode
,
2677 = gen_rtx_EXPR_LIST (REG_EQUAL
,
2678 reg_equiv_memory_loc
[regno
],
2681 *recog_operand_loc
[i
] = recog_operand
[i
]
2682 = gen_rtx_MEM (GET_MODE (recog_operand
[i
]), address
);
2683 RTX_UNCHANGING_P (recog_operand
[i
])
2684 = RTX_UNCHANGING_P (regno_reg_rtx
[regno
]);
2685 find_reloads_address (GET_MODE (recog_operand
[i
]),
2686 recog_operand_loc
[i
],
2687 XEXP (recog_operand
[i
], 0),
2688 &XEXP (recog_operand
[i
], 0),
2689 i
, address_type
[i
], ind_levels
, insn
);
2690 substed_operand
[i
] = recog_operand
[i
] = *recog_operand_loc
[i
];
2693 /* If the operand is still a register (we didn't replace it with an
2694 equivalent), get the preferred class to reload it into. */
2695 code
= GET_CODE (recog_operand
[i
]);
2697 = ((code
== REG
&& REGNO (recog_operand
[i
]) >= FIRST_PSEUDO_REGISTER
)
2698 ? reg_preferred_class (REGNO (recog_operand
[i
])) : NO_REGS
);
2700 = (code
== REG
&& REGNO (recog_operand
[i
]) >= FIRST_PSEUDO_REGISTER
2701 && reg_alternate_class (REGNO (recog_operand
[i
])) == NO_REGS
);
2704 /* If this is simply a copy from operand 1 to operand 0, merge the
2705 preferred classes for the operands. */
2706 if (set
!= 0 && noperands
>= 2 && recog_operand
[0] == SET_DEST (set
)
2707 && recog_operand
[1] == SET_SRC (set
))
2709 preferred_class
[0] = preferred_class
[1]
2710 = reg_class_subunion
[(int) preferred_class
[0]][(int) preferred_class
[1]];
2711 pref_or_nothing
[0] |= pref_or_nothing
[1];
2712 pref_or_nothing
[1] |= pref_or_nothing
[0];
2715 /* Now see what we need for pseudo-regs that didn't get hard regs
2716 or got the wrong kind of hard reg. For this, we must consider
2717 all the operands together against the register constraints. */
2719 best
= MAX_RECOG_OPERANDS
* 2 + 600;
2722 goal_alternative_swapped
= 0;
2725 /* The constraints are made of several alternatives.
2726 Each operand's constraint looks like foo,bar,... with commas
2727 separating the alternatives. The first alternatives for all
2728 operands go together, the second alternatives go together, etc.
2730 First loop over alternatives. */
2732 for (this_alternative_number
= 0;
2733 this_alternative_number
< n_alternatives
;
2734 this_alternative_number
++)
2736 /* Loop over operands for one constraint alternative. */
2737 /* LOSERS counts those that don't fit this alternative
2738 and would require loading. */
2740 /* BAD is set to 1 if it some operand can't fit this alternative
2741 even after reloading. */
2743 /* REJECT is a count of how undesirable this alternative says it is
2744 if any reloading is required. If the alternative matches exactly
2745 then REJECT is ignored, but otherwise it gets this much
2746 counted against it in addition to the reloading needed. Each
2747 ? counts three times here since we want the disparaging caused by
2748 a bad register class to only count 1/3 as much. */
2751 this_earlyclobber
= 0;
2753 for (i
= 0; i
< noperands
; i
++)
2755 register char *p
= constraints
[i
];
2756 register int win
= 0;
2757 /* 0 => this operand can be reloaded somehow for this alternative */
2759 /* 0 => this operand can be reloaded if the alternative allows regs. */
2762 register rtx operand
= recog_operand
[i
];
2764 /* Nonzero means this is a MEM that must be reloaded into a reg
2765 regardless of what the constraint says. */
2766 int force_reload
= 0;
2768 /* Nonzero if a constant forced into memory would be OK for this
2771 int earlyclobber
= 0;
2773 /* If the predicate accepts a unary operator, it means that
2774 we need to reload the operand, but do not do this for
2775 match_operator and friends. */
2776 if (GET_RTX_CLASS (GET_CODE (operand
)) == '1' && *p
!= 0)
2777 operand
= XEXP (operand
, 0);
2779 /* If the operand is a SUBREG, extract
2780 the REG or MEM (or maybe even a constant) within.
2781 (Constants can occur as a result of reg_equiv_constant.) */
2783 while (GET_CODE (operand
) == SUBREG
)
2785 offset
+= SUBREG_WORD (operand
);
2786 operand
= SUBREG_REG (operand
);
2787 /* Force reload if this is a constant or PLUS or if there may
2788 be a problem accessing OPERAND in the outer mode. */
2789 if (CONSTANT_P (operand
)
2790 || GET_CODE (operand
) == PLUS
2791 /* We must force a reload of paradoxical SUBREGs
2792 of a MEM because the alignment of the inner value
2793 may not be enough to do the outer reference. On
2794 big-endian machines, it may also reference outside
2797 On machines that extend byte operations and we have a
2798 SUBREG where both the inner and outer modes are no wider
2799 than a word and the inner mode is narrower, is integral,
2800 and gets extended when loaded from memory, combine.c has
2801 made assumptions about the behavior of the machine in such
2802 register access. If the data is, in fact, in memory we
2803 must always load using the size assumed to be in the
2804 register and let the insn do the different-sized
2807 This is doubly true if WORD_REGISTER_OPERATIONS. In
2808 this case eliminate_regs has left non-paradoxical
2809 subregs for push_reloads to see. Make sure it does
2810 by forcing the reload.
2812 ??? When is it right at this stage to have a subreg
2813 of a mem that is _not_ to be handled specialy? IMO
2814 those should have been reduced to just a mem. */
2815 || ((GET_CODE (operand
) == MEM
2816 || (GET_CODE (operand
)== REG
2817 && REGNO (operand
) >= FIRST_PSEUDO_REGISTER
))
2818 #ifndef WORD_REGISTER_OPERATIONS
2819 && (((GET_MODE_BITSIZE (GET_MODE (operand
))
2820 < BIGGEST_ALIGNMENT
)
2821 && (GET_MODE_SIZE (operand_mode
[i
])
2822 > GET_MODE_SIZE (GET_MODE (operand
))))
2823 || (GET_CODE (operand
) == MEM
&& BYTES_BIG_ENDIAN
)
2824 #ifdef LOAD_EXTEND_OP
2825 || (GET_MODE_SIZE (operand_mode
[i
]) <= UNITS_PER_WORD
2826 && (GET_MODE_SIZE (GET_MODE (operand
))
2828 && (GET_MODE_SIZE (operand_mode
[i
])
2829 > GET_MODE_SIZE (GET_MODE (operand
)))
2830 && INTEGRAL_MODE_P (GET_MODE (operand
))
2831 && LOAD_EXTEND_OP (GET_MODE (operand
)) != NIL
)
2836 /* Subreg of a hard reg which can't handle the subreg's mode
2837 or which would handle that mode in the wrong number of
2838 registers for subregging to work. */
2839 || (GET_CODE (operand
) == REG
2840 && REGNO (operand
) < FIRST_PSEUDO_REGISTER
2841 && ((GET_MODE_SIZE (operand_mode
[i
]) <= UNITS_PER_WORD
2842 && (GET_MODE_SIZE (GET_MODE (operand
))
2844 && ((GET_MODE_SIZE (GET_MODE (operand
))
2846 != HARD_REGNO_NREGS (REGNO (operand
),
2847 GET_MODE (operand
))))
2848 || ! HARD_REGNO_MODE_OK (REGNO (operand
) + offset
,
2853 this_alternative
[i
] = (int) NO_REGS
;
2854 this_alternative_win
[i
] = 0;
2855 this_alternative_offmemok
[i
] = 0;
2856 this_alternative_earlyclobber
[i
] = 0;
2857 this_alternative_matches
[i
] = -1;
2859 /* An empty constraint or empty alternative
2860 allows anything which matched the pattern. */
2861 if (*p
== 0 || *p
== ',')
2864 /* Scan this alternative's specs for this operand;
2865 set WIN if the operand fits any letter in this alternative.
2866 Otherwise, clear BADOP if this operand could
2867 fit some letter after reloads,
2868 or set WINREG if this operand could fit after reloads
2869 provided the constraint allows some registers. */
2871 while (*p
&& (c
= *p
++) != ',')
2880 /* The last operand should not be marked commutative. */
2881 if (i
!= noperands
- 1)
2894 /* Ignore rest of this alternative as far as
2895 reloading is concerned. */
2896 while (*p
&& *p
!= ',') p
++;
2905 this_alternative_matches
[i
] = c
;
2906 /* We are supposed to match a previous operand.
2907 If we do, we win if that one did.
2908 If we do not, count both of the operands as losers.
2909 (This is too conservative, since most of the time
2910 only a single reload insn will be needed to make
2911 the two operands win. As a result, this alternative
2912 may be rejected when it is actually desirable.) */
2913 if ((swapped
&& (c
!= commutative
|| i
!= commutative
+ 1))
2914 /* If we are matching as if two operands were swapped,
2915 also pretend that operands_match had been computed
2917 But if I is the second of those and C is the first,
2918 don't exchange them, because operands_match is valid
2919 only on one side of its diagonal. */
2921 [(c
== commutative
|| c
== commutative
+ 1)
2922 ? 2*commutative
+ 1 - c
: c
]
2923 [(i
== commutative
|| i
== commutative
+ 1)
2924 ? 2*commutative
+ 1 - i
: i
])
2925 : operands_match
[c
][i
])
2927 /* If we are matching a non-offsettable address where an
2928 offsettable address was expected, then we must reject
2929 this combination, because we can't reload it. */
2930 if (this_alternative_offmemok
[c
]
2931 && GET_CODE (recog_operand
[c
]) == MEM
2932 && this_alternative
[c
] == (int) NO_REGS
2933 && ! this_alternative_win
[c
])
2936 win
= this_alternative_win
[c
];
2940 /* Operands don't match. */
2942 /* Retroactively mark the operand we had to match
2943 as a loser, if it wasn't already. */
2944 if (this_alternative_win
[c
])
2946 this_alternative_win
[c
] = 0;
2947 if (this_alternative
[c
] == (int) NO_REGS
)
2949 /* But count the pair only once in the total badness of
2950 this alternative, if the pair can be a dummy reload. */
2952 = find_dummy_reload (recog_operand
[i
], recog_operand
[c
],
2953 recog_operand_loc
[i
], recog_operand_loc
[c
],
2954 operand_mode
[i
], operand_mode
[c
],
2955 this_alternative
[c
], -1,
2956 this_alternative_earlyclobber
[c
]);
2961 /* This can be fixed with reloads if the operand
2962 we are supposed to match can be fixed with reloads. */
2964 this_alternative
[i
] = this_alternative
[c
];
2966 /* If we have to reload this operand and some previous
2967 operand also had to match the same thing as this
2968 operand, we don't know how to do that. So reject this
2970 if (! win
|| force_reload
)
2971 for (j
= 0; j
< i
; j
++)
2972 if (this_alternative_matches
[j
]
2973 == this_alternative_matches
[i
])
2979 /* All necessary reloads for an address_operand
2980 were handled in find_reloads_address. */
2981 this_alternative
[i
] = (int) BASE_REG_CLASS
;
2988 if (GET_CODE (operand
) == MEM
2989 || (GET_CODE (operand
) == REG
2990 && REGNO (operand
) >= FIRST_PSEUDO_REGISTER
2991 && reg_renumber
[REGNO (operand
)] < 0))
2993 if (CONSTANT_P (operand
)
2994 /* force_const_mem does not accept HIGH. */
2995 && GET_CODE (operand
) != HIGH
)
3001 if (GET_CODE (operand
) == MEM
3002 && ! address_reloaded
[i
]
3003 && (GET_CODE (XEXP (operand
, 0)) == PRE_DEC
3004 || GET_CODE (XEXP (operand
, 0)) == POST_DEC
))
3009 if (GET_CODE (operand
) == MEM
3010 && ! address_reloaded
[i
]
3011 && (GET_CODE (XEXP (operand
, 0)) == PRE_INC
3012 || GET_CODE (XEXP (operand
, 0)) == POST_INC
))
3016 /* Memory operand whose address is not offsettable. */
3020 if (GET_CODE (operand
) == MEM
3021 && ! (ind_levels
? offsettable_memref_p (operand
)
3022 : offsettable_nonstrict_memref_p (operand
))
3023 /* Certain mem addresses will become offsettable
3024 after they themselves are reloaded. This is important;
3025 we don't want our own handling of unoffsettables
3026 to override the handling of reg_equiv_address. */
3027 && !(GET_CODE (XEXP (operand
, 0)) == REG
3029 || reg_equiv_address
[REGNO (XEXP (operand
, 0))] != 0)))
3033 /* Memory operand whose address is offsettable. */
3037 if ((GET_CODE (operand
) == MEM
3038 /* If IND_LEVELS, find_reloads_address won't reload a
3039 pseudo that didn't get a hard reg, so we have to
3040 reject that case. */
3041 && (ind_levels
? offsettable_memref_p (operand
)
3042 : offsettable_nonstrict_memref_p (operand
)))
3043 /* A reloaded auto-increment address is offsettable,
3044 because it is now just a simple register indirect. */
3045 || (GET_CODE (operand
) == MEM
3046 && address_reloaded
[i
]
3047 && (GET_CODE (XEXP (operand
, 0)) == PRE_INC
3048 || GET_CODE (XEXP (operand
, 0)) == PRE_DEC
3049 || GET_CODE (XEXP (operand
, 0)) == POST_INC
3050 || GET_CODE (XEXP (operand
, 0)) == POST_DEC
))
3051 /* Certain mem addresses will become offsettable
3052 after they themselves are reloaded. This is important;
3053 we don't want our own handling of unoffsettables
3054 to override the handling of reg_equiv_address. */
3055 || (GET_CODE (operand
) == MEM
3056 && GET_CODE (XEXP (operand
, 0)) == REG
3058 || reg_equiv_address
[REGNO (XEXP (operand
, 0))] != 0))
3059 || (GET_CODE (operand
) == REG
3060 && REGNO (operand
) >= FIRST_PSEUDO_REGISTER
3061 && reg_renumber
[REGNO (operand
)] < 0
3062 /* If reg_equiv_address is nonzero, we will be
3063 loading it into a register; hence it will be
3064 offsettable, but we cannot say that reg_equiv_mem
3065 is offsettable without checking. */
3066 && ((reg_equiv_mem
[REGNO (operand
)] != 0
3067 && offsettable_memref_p (reg_equiv_mem
[REGNO (operand
)]))
3068 || (reg_equiv_address
[REGNO (operand
)] != 0))))
3070 /* force_const_mem does not accept HIGH. */
3071 if ((CONSTANT_P (operand
) && GET_CODE (operand
) != HIGH
)
3072 || GET_CODE (operand
) == MEM
)
3079 /* Output operand that is stored before the need for the
3080 input operands (and their index registers) is over. */
3081 earlyclobber
= 1, this_earlyclobber
= 1;
3085 #ifndef REAL_ARITHMETIC
3086 /* Match any floating double constant, but only if
3087 we can examine the bits of it reliably. */
3088 if ((HOST_FLOAT_FORMAT
!= TARGET_FLOAT_FORMAT
3089 || HOST_BITS_PER_WIDE_INT
!= BITS_PER_WORD
)
3090 && GET_MODE (operand
) != VOIDmode
&& ! flag_pretend_float
)
3093 if (GET_CODE (operand
) == CONST_DOUBLE
)
3098 if (GET_CODE (operand
) == CONST_DOUBLE
)
3104 if (GET_CODE (operand
) == CONST_DOUBLE
3105 && CONST_DOUBLE_OK_FOR_LETTER_P (operand
, c
))
3110 if (GET_CODE (operand
) == CONST_INT
3111 || (GET_CODE (operand
) == CONST_DOUBLE
3112 && GET_MODE (operand
) == VOIDmode
))
3115 if (CONSTANT_P (operand
)
3116 #ifdef LEGITIMATE_PIC_OPERAND_P
3117 && (! flag_pic
|| LEGITIMATE_PIC_OPERAND_P (operand
))
3124 if (GET_CODE (operand
) == CONST_INT
3125 || (GET_CODE (operand
) == CONST_DOUBLE
3126 && GET_MODE (operand
) == VOIDmode
))
3138 if (GET_CODE (operand
) == CONST_INT
3139 && CONST_OK_FOR_LETTER_P (INTVAL (operand
), c
))
3149 /* A PLUS is never a valid operand, but reload can make
3150 it from a register when eliminating registers. */
3151 && GET_CODE (operand
) != PLUS
3152 /* A SCRATCH is not a valid operand. */
3153 && GET_CODE (operand
) != SCRATCH
3154 #ifdef LEGITIMATE_PIC_OPERAND_P
3155 && (! CONSTANT_P (operand
)
3157 || LEGITIMATE_PIC_OPERAND_P (operand
))
3159 && (GENERAL_REGS
== ALL_REGS
3160 || GET_CODE (operand
) != REG
3161 || (REGNO (operand
) >= FIRST_PSEUDO_REGISTER
3162 && reg_renumber
[REGNO (operand
)] < 0)))
3164 /* Drop through into 'r' case */
3168 = (int) reg_class_subunion
[this_alternative
[i
]][(int) GENERAL_REGS
];
3171 #ifdef EXTRA_CONSTRAINT
3177 if (EXTRA_CONSTRAINT (operand
, c
))
3184 = (int) reg_class_subunion
[this_alternative
[i
]][(int) REG_CLASS_FROM_LETTER (c
)];
3187 if (GET_MODE (operand
) == BLKmode
)
3190 if (GET_CODE (operand
) == REG
3191 && reg_fits_class_p (operand
, this_alternative
[i
],
3192 offset
, GET_MODE (recog_operand
[i
])))
3199 /* If this operand could be handled with a reg,
3200 and some reg is allowed, then this operand can be handled. */
3201 if (winreg
&& this_alternative
[i
] != (int) NO_REGS
)
3204 /* Record which operands fit this alternative. */
3205 this_alternative_earlyclobber
[i
] = earlyclobber
;
3206 if (win
&& ! force_reload
)
3207 this_alternative_win
[i
] = 1;
3210 int const_to_mem
= 0;
3212 this_alternative_offmemok
[i
] = offmemok
;
3216 /* Alternative loses if it has no regs for a reg operand. */
3217 if (GET_CODE (operand
) == REG
3218 && this_alternative
[i
] == (int) NO_REGS
3219 && this_alternative_matches
[i
] < 0)
3222 /* If this is a constant that is reloaded into the desired
3223 class by copying it to memory first, count that as another
3224 reload. This is consistent with other code and is
3225 required to avoid choosing another alternative when
3226 the constant is moved into memory by this function on
3227 an early reload pass. Note that the test here is
3228 precisely the same as in the code below that calls
3230 if (CONSTANT_P (operand
)
3231 /* force_const_mem does not accept HIGH. */
3232 && GET_CODE (operand
) != HIGH
3233 && ((PREFERRED_RELOAD_CLASS (operand
,
3234 (enum reg_class
) this_alternative
[i
])
3236 || no_input_reloads
)
3237 && operand_mode
[i
] != VOIDmode
)
3240 if (this_alternative
[i
] != (int) NO_REGS
)
3244 /* If we can't reload this value at all, reject this
3245 alternative. Note that we could also lose due to
3246 LIMIT_RELOAD_RELOAD_CLASS, but we don't check that
3249 if (! CONSTANT_P (operand
)
3250 && (enum reg_class
) this_alternative
[i
] != NO_REGS
3251 && (PREFERRED_RELOAD_CLASS (operand
,
3252 (enum reg_class
) this_alternative
[i
])
3256 /* Alternative loses if it requires a type of reload not
3257 permitted for this insn. We can always reload SCRATCH
3258 and objects with a REG_UNUSED note. */
3259 else if (GET_CODE (operand
) != SCRATCH
3260 && modified
[i
] != RELOAD_READ
&& no_output_reloads
3261 && ! find_reg_note (insn
, REG_UNUSED
, operand
))
3263 else if (modified
[i
] != RELOAD_WRITE
&& no_input_reloads
3268 /* We prefer to reload pseudos over reloading other things,
3269 since such reloads may be able to be eliminated later.
3270 If we are reloading a SCRATCH, we won't be generating any
3271 insns, just using a register, so it is also preferred.
3272 So bump REJECT in other cases. Don't do this in the
3273 case where we are forcing a constant into memory and
3274 it will then win since we don't want to have a different
3275 alternative match then. */
3276 if (! (GET_CODE (operand
) == REG
3277 && REGNO (operand
) >= FIRST_PSEUDO_REGISTER
)
3278 && GET_CODE (operand
) != SCRATCH
3279 && ! (const_to_mem
&& constmemok
))
3282 /* Input reloads can be inherited more often than output
3283 reloads can be removed, so penalize output reloads. */
3284 if (operand_type
[i
] != RELOAD_FOR_INPUT
3285 && GET_CODE (operand
) != SCRATCH
)
3289 /* If this operand is a pseudo register that didn't get a hard
3290 reg and this alternative accepts some register, see if the
3291 class that we want is a subset of the preferred class for this
3292 register. If not, but it intersects that class, use the
3293 preferred class instead. If it does not intersect the preferred
3294 class, show that usage of this alternative should be discouraged;
3295 it will be discouraged more still if the register is `preferred
3296 or nothing'. We do this because it increases the chance of
3297 reusing our spill register in a later insn and avoiding a pair
3298 of memory stores and loads.
3300 Don't bother with this if this alternative will accept this
3303 Don't do this for a multiword operand, since it is only a
3304 small win and has the risk of requiring more spill registers,
3305 which could cause a large loss.
3307 Don't do this if the preferred class has only one register
3308 because we might otherwise exhaust the class. */
3311 if (! win
&& this_alternative
[i
] != (int) NO_REGS
3312 && GET_MODE_SIZE (operand_mode
[i
]) <= UNITS_PER_WORD
3313 && reg_class_size
[(int) preferred_class
[i
]] > 1)
3315 if (! reg_class_subset_p (this_alternative
[i
],
3316 preferred_class
[i
]))
3318 /* Since we don't have a way of forming the intersection,
3319 we just do something special if the preferred class
3320 is a subset of the class we have; that's the most
3321 common case anyway. */
3322 if (reg_class_subset_p (preferred_class
[i
],
3323 this_alternative
[i
]))
3324 this_alternative
[i
] = (int) preferred_class
[i
];
3326 reject
+= (2 + 2 * pref_or_nothing
[i
]);
3331 /* Now see if any output operands that are marked "earlyclobber"
3332 in this alternative conflict with any input operands
3333 or any memory addresses. */
3335 for (i
= 0; i
< noperands
; i
++)
3336 if (this_alternative_earlyclobber
[i
]
3337 && this_alternative_win
[i
])
3339 struct decomposition early_data
;
3341 early_data
= decompose (recog_operand
[i
]);
3343 if (modified
[i
] == RELOAD_READ
)
3345 if (this_insn_is_asm
)
3346 warning_for_asm (this_insn
,
3347 "`&' constraint used with input operand");
3353 if (this_alternative
[i
] == NO_REGS
)
3355 this_alternative_earlyclobber
[i
] = 0;
3356 if (this_insn_is_asm
)
3357 error_for_asm (this_insn
,
3358 "`&' constraint used with no register class");
3363 for (j
= 0; j
< noperands
; j
++)
3364 /* Is this an input operand or a memory ref? */
3365 if ((GET_CODE (recog_operand
[j
]) == MEM
3366 || modified
[j
] != RELOAD_WRITE
)
3368 /* Ignore things like match_operator operands. */
3369 && *constraints1
[j
] != 0
3370 /* Don't count an input operand that is constrained to match
3371 the early clobber operand. */
3372 && ! (this_alternative_matches
[j
] == i
3373 && rtx_equal_p (recog_operand
[i
], recog_operand
[j
]))
3374 /* Is it altered by storing the earlyclobber operand? */
3375 && !immune_p (recog_operand
[j
], recog_operand
[i
], early_data
))
3377 /* If the output is in a single-reg class,
3378 it's costly to reload it, so reload the input instead. */
3379 if (reg_class_size
[this_alternative
[i
]] == 1
3380 && (GET_CODE (recog_operand
[j
]) == REG
3381 || GET_CODE (recog_operand
[j
]) == SUBREG
))
3384 this_alternative_win
[j
] = 0;
3389 /* If an earlyclobber operand conflicts with something,
3390 it must be reloaded, so request this and count the cost. */
3394 this_alternative_win
[i
] = 0;
3395 for (j
= 0; j
< noperands
; j
++)
3396 if (this_alternative_matches
[j
] == i
3397 && this_alternative_win
[j
])
3399 this_alternative_win
[j
] = 0;
3405 /* If one alternative accepts all the operands, no reload required,
3406 choose that alternative; don't consider the remaining ones. */
3409 /* Unswap these so that they are never swapped at `finish'. */
3410 if (commutative
>= 0)
3412 recog_operand
[commutative
] = substed_operand
[commutative
];
3413 recog_operand
[commutative
+ 1]
3414 = substed_operand
[commutative
+ 1];
3416 for (i
= 0; i
< noperands
; i
++)
3418 goal_alternative_win
[i
] = 1;
3419 goal_alternative
[i
] = this_alternative
[i
];
3420 goal_alternative_offmemok
[i
] = this_alternative_offmemok
[i
];
3421 goal_alternative_matches
[i
] = this_alternative_matches
[i
];
3422 goal_alternative_earlyclobber
[i
]
3423 = this_alternative_earlyclobber
[i
];
3425 goal_alternative_number
= this_alternative_number
;
3426 goal_alternative_swapped
= swapped
;
3427 goal_earlyclobber
= this_earlyclobber
;
3431 /* REJECT, set by the ! and ? constraint characters and when a register
3432 would be reloaded into a non-preferred class, discourages the use of
3433 this alternative for a reload goal. REJECT is incremented by six
3434 for each ? and two for each non-preferred class. */
3435 losers
= losers
* 6 + reject
;
3437 /* If this alternative can be made to work by reloading,
3438 and it needs less reloading than the others checked so far,
3439 record it as the chosen goal for reloading. */
3440 if (! bad
&& best
> losers
)
3442 for (i
= 0; i
< noperands
; i
++)
3444 goal_alternative
[i
] = this_alternative
[i
];
3445 goal_alternative_win
[i
] = this_alternative_win
[i
];
3446 goal_alternative_offmemok
[i
] = this_alternative_offmemok
[i
];
3447 goal_alternative_matches
[i
] = this_alternative_matches
[i
];
3448 goal_alternative_earlyclobber
[i
]
3449 = this_alternative_earlyclobber
[i
];
3451 goal_alternative_swapped
= swapped
;
3453 goal_alternative_number
= this_alternative_number
;
3454 goal_earlyclobber
= this_earlyclobber
;
3458 /* If insn is commutative (it's safe to exchange a certain pair of operands)
3459 then we need to try each alternative twice,
3460 the second time matching those two operands
3461 as if we had exchanged them.
3462 To do this, really exchange them in operands.
3464 If we have just tried the alternatives the second time,
3465 return operands to normal and drop through. */
3467 if (commutative
>= 0)
3472 register enum reg_class tclass
;
3475 recog_operand
[commutative
] = substed_operand
[commutative
+ 1];
3476 recog_operand
[commutative
+ 1] = substed_operand
[commutative
];
3478 tclass
= preferred_class
[commutative
];
3479 preferred_class
[commutative
] = preferred_class
[commutative
+ 1];
3480 preferred_class
[commutative
+ 1] = tclass
;
3482 t
= pref_or_nothing
[commutative
];
3483 pref_or_nothing
[commutative
] = pref_or_nothing
[commutative
+ 1];
3484 pref_or_nothing
[commutative
+ 1] = t
;
3486 bcopy ((char *) constraints1
, (char *) constraints
,
3487 noperands
* sizeof (char *));
3492 recog_operand
[commutative
] = substed_operand
[commutative
];
3493 recog_operand
[commutative
+ 1] = substed_operand
[commutative
+ 1];
3497 /* The operands don't meet the constraints.
3498 goal_alternative describes the alternative
3499 that we could reach by reloading the fewest operands.
3500 Reload so as to fit it. */
3502 if (best
== MAX_RECOG_OPERANDS
+ 300)
3504 /* No alternative works with reloads?? */
3505 if (insn_code_number
>= 0)
3507 error_for_asm (insn
, "inconsistent operand constraints in an `asm'");
3508 /* Avoid further trouble with this insn. */
3509 PATTERN (insn
) = gen_rtx_USE (VOIDmode
, const0_rtx
);
3514 /* Jump to `finish' from above if all operands are valid already.
3515 In that case, goal_alternative_win is all 1. */
3518 /* Right now, for any pair of operands I and J that are required to match,
3520 goal_alternative_matches[J] is I.
3521 Set up goal_alternative_matched as the inverse function:
3522 goal_alternative_matched[I] = J. */
3524 for (i
= 0; i
< noperands
; i
++)
3525 goal_alternative_matched
[i
] = -1;
3527 for (i
= 0; i
< noperands
; i
++)
3528 if (! goal_alternative_win
[i
]
3529 && goal_alternative_matches
[i
] >= 0)
3530 goal_alternative_matched
[goal_alternative_matches
[i
]] = i
;
3532 /* If the best alternative is with operands 1 and 2 swapped,
3533 consider them swapped before reporting the reloads. Update the
3534 operand numbers of any reloads already pushed. */
3536 if (goal_alternative_swapped
)
3540 tem
= substed_operand
[commutative
];
3541 substed_operand
[commutative
] = substed_operand
[commutative
+ 1];
3542 substed_operand
[commutative
+ 1] = tem
;
3543 tem
= recog_operand
[commutative
];
3544 recog_operand
[commutative
] = recog_operand
[commutative
+ 1];
3545 recog_operand
[commutative
+ 1] = tem
;
3547 for (i
= 0; i
< n_reloads
; i
++)
3549 if (reload_opnum
[i
] == commutative
)
3550 reload_opnum
[i
] = commutative
+ 1;
3551 else if (reload_opnum
[i
] == commutative
+ 1)
3552 reload_opnum
[i
] = commutative
;
3556 /* Perform whatever substitutions on the operands we are supposed
3557 to make due to commutativity or replacement of registers
3558 with equivalent constants or memory slots. */
3560 for (i
= 0; i
< noperands
; i
++)
3562 *recog_operand_loc
[i
] = substed_operand
[i
];
3563 /* While we are looping on operands, initialize this. */
3564 operand_reloadnum
[i
] = -1;
3566 /* If this is an earlyclobber operand, we need to widen the scope.
3567 The reload must remain valid from the start of the insn being
3568 reloaded until after the operand is stored into its destination.
3569 We approximate this with RELOAD_OTHER even though we know that we
3570 do not conflict with RELOAD_FOR_INPUT_ADDRESS reloads.
3572 One special case that is worth checking is when we have an
3573 output that is earlyclobber but isn't used past the insn (typically
3574 a SCRATCH). In this case, we only need have the reload live
3575 through the insn itself, but not for any of our input or output
3578 In any case, anything needed to address this operand can remain
3579 however they were previously categorized. */
3581 if (goal_alternative_earlyclobber
[i
])
3583 = (find_reg_note (insn
, REG_UNUSED
, recog_operand
[i
])
3584 ? RELOAD_FOR_INSN
: RELOAD_OTHER
);
3587 /* Any constants that aren't allowed and can't be reloaded
3588 into registers are here changed into memory references. */
3589 for (i
= 0; i
< noperands
; i
++)
3590 if (! goal_alternative_win
[i
]
3591 && CONSTANT_P (recog_operand
[i
])
3592 /* force_const_mem does not accept HIGH. */
3593 && GET_CODE (recog_operand
[i
]) != HIGH
3594 && ((PREFERRED_RELOAD_CLASS (recog_operand
[i
],
3595 (enum reg_class
) goal_alternative
[i
])
3597 || no_input_reloads
)
3598 && operand_mode
[i
] != VOIDmode
)
3600 *recog_operand_loc
[i
] = recog_operand
[i
]
3601 = find_reloads_toplev (force_const_mem (operand_mode
[i
],
3603 i
, address_type
[i
], ind_levels
, 0);
3604 if (alternative_allows_memconst (constraints1
[i
],
3605 goal_alternative_number
))
3606 goal_alternative_win
[i
] = 1;
3609 /* Record the values of the earlyclobber operands for the caller. */
3610 if (goal_earlyclobber
)
3611 for (i
= 0; i
< noperands
; i
++)
3612 if (goal_alternative_earlyclobber
[i
])
3613 reload_earlyclobbers
[n_earlyclobbers
++] = recog_operand
[i
];
3615 /* Now record reloads for all the operands that need them. */
3616 for (i
= 0; i
< noperands
; i
++)
3617 if (! goal_alternative_win
[i
])
3619 /* Operands that match previous ones have already been handled. */
3620 if (goal_alternative_matches
[i
] >= 0)
3622 /* Handle an operand with a nonoffsettable address
3623 appearing where an offsettable address will do
3624 by reloading the address into a base register.
3626 ??? We can also do this when the operand is a register and
3627 reg_equiv_mem is not offsettable, but this is a bit tricky,
3628 so we don't bother with it. It may not be worth doing. */
3629 else if (goal_alternative_matched
[i
] == -1
3630 && goal_alternative_offmemok
[i
]
3631 && GET_CODE (recog_operand
[i
]) == MEM
)
3633 operand_reloadnum
[i
]
3634 = push_reload (XEXP (recog_operand
[i
], 0), NULL_RTX
,
3635 &XEXP (recog_operand
[i
], 0), NULL_PTR
,
3636 BASE_REG_CLASS
, GET_MODE (XEXP (recog_operand
[i
], 0)),
3637 VOIDmode
, 0, 0, i
, RELOAD_FOR_INPUT
);
3638 reload_inc
[operand_reloadnum
[i
]]
3639 = GET_MODE_SIZE (GET_MODE (recog_operand
[i
]));
3641 /* If this operand is an output, we will have made any
3642 reloads for its address as RELOAD_FOR_OUTPUT_ADDRESS, but
3643 now we are treating part of the operand as an input, so
3644 we must change these to RELOAD_FOR_INPUT_ADDRESS. */
3646 if (modified
[i
] == RELOAD_WRITE
)
3648 for (j
= 0; j
< n_reloads
; j
++)
3650 if (reload_opnum
[j
] == i
)
3652 if (reload_when_needed
[j
] == RELOAD_FOR_OUTPUT_ADDRESS
)
3653 reload_when_needed
[j
] = RELOAD_FOR_INPUT_ADDRESS
;
3654 else if (reload_when_needed
[j
]
3655 == RELOAD_FOR_OUTADDR_ADDRESS
)
3656 reload_when_needed
[j
] = RELOAD_FOR_INPADDR_ADDRESS
;
3661 else if (goal_alternative_matched
[i
] == -1)
3662 operand_reloadnum
[i
]
3663 = push_reload (modified
[i
] != RELOAD_WRITE
? recog_operand
[i
] : 0,
3664 modified
[i
] != RELOAD_READ
? recog_operand
[i
] : 0,
3665 (modified
[i
] != RELOAD_WRITE
3666 ? recog_operand_loc
[i
] : 0),
3667 modified
[i
] != RELOAD_READ
? recog_operand_loc
[i
] : 0,
3668 (enum reg_class
) goal_alternative
[i
],
3669 (modified
[i
] == RELOAD_WRITE
3670 ? VOIDmode
: operand_mode
[i
]),
3671 (modified
[i
] == RELOAD_READ
3672 ? VOIDmode
: operand_mode
[i
]),
3673 (insn_code_number
< 0 ? 0
3674 : insn_operand_strict_low
[insn_code_number
][i
]),
3675 0, i
, operand_type
[i
]);
3676 /* In a matching pair of operands, one must be input only
3677 and the other must be output only.
3678 Pass the input operand as IN and the other as OUT. */
3679 else if (modified
[i
] == RELOAD_READ
3680 && modified
[goal_alternative_matched
[i
]] == RELOAD_WRITE
)
3682 operand_reloadnum
[i
]
3683 = push_reload (recog_operand
[i
],
3684 recog_operand
[goal_alternative_matched
[i
]],
3685 recog_operand_loc
[i
],
3686 recog_operand_loc
[goal_alternative_matched
[i
]],
3687 (enum reg_class
) goal_alternative
[i
],
3689 operand_mode
[goal_alternative_matched
[i
]],
3690 0, 0, i
, RELOAD_OTHER
);
3691 operand_reloadnum
[goal_alternative_matched
[i
]] = output_reloadnum
;
3693 else if (modified
[i
] == RELOAD_WRITE
3694 && modified
[goal_alternative_matched
[i
]] == RELOAD_READ
)
3696 operand_reloadnum
[goal_alternative_matched
[i
]]
3697 = push_reload (recog_operand
[goal_alternative_matched
[i
]],
3699 recog_operand_loc
[goal_alternative_matched
[i
]],
3700 recog_operand_loc
[i
],
3701 (enum reg_class
) goal_alternative
[i
],
3702 operand_mode
[goal_alternative_matched
[i
]],
3704 0, 0, i
, RELOAD_OTHER
);
3705 operand_reloadnum
[i
] = output_reloadnum
;
3707 else if (insn_code_number
>= 0)
3711 error_for_asm (insn
, "inconsistent operand constraints in an `asm'");
3712 /* Avoid further trouble with this insn. */
3713 PATTERN (insn
) = gen_rtx_USE (VOIDmode
, const0_rtx
);
3718 else if (goal_alternative_matched
[i
] < 0
3719 && goal_alternative_matches
[i
] < 0
3722 /* For each non-matching operand that's a MEM or a pseudo-register
3723 that didn't get a hard register, make an optional reload.
3724 This may get done even if the insn needs no reloads otherwise. */
3726 rtx operand
= recog_operand
[i
];
3728 while (GET_CODE (operand
) == SUBREG
)
3729 operand
= XEXP (operand
, 0);
3730 if ((GET_CODE (operand
) == MEM
3731 || (GET_CODE (operand
) == REG
3732 && REGNO (operand
) >= FIRST_PSEUDO_REGISTER
))
3733 && (enum reg_class
) goal_alternative
[i
] != NO_REGS
3734 && ! no_input_reloads
3735 /* Optional output reloads don't do anything and we mustn't
3736 make in-out reloads on insns that are not permitted output
3738 && (modified
[i
] == RELOAD_READ
3739 || (modified
[i
] == RELOAD_READ_WRITE
&& ! no_output_reloads
)))
3740 operand_reloadnum
[i
]
3741 = push_reload (modified
[i
] != RELOAD_WRITE
? recog_operand
[i
] : 0,
3742 modified
[i
] != RELOAD_READ
? recog_operand
[i
] : 0,
3743 (modified
[i
] != RELOAD_WRITE
3744 ? recog_operand_loc
[i
] : 0),
3745 (modified
[i
] != RELOAD_READ
3746 ? recog_operand_loc
[i
] : 0),
3747 (enum reg_class
) goal_alternative
[i
],
3748 (modified
[i
] == RELOAD_WRITE
3749 ? VOIDmode
: operand_mode
[i
]),
3750 (modified
[i
] == RELOAD_READ
3751 ? VOIDmode
: operand_mode
[i
]),
3752 (insn_code_number
< 0 ? 0
3753 : insn_operand_strict_low
[insn_code_number
][i
]),
3754 1, i
, operand_type
[i
]);
3756 else if (goal_alternative_matches
[i
] >= 0
3757 && goal_alternative_win
[goal_alternative_matches
[i
]]
3758 && modified
[i
] == RELOAD_READ
3759 && modified
[goal_alternative_matches
[i
]] == RELOAD_WRITE
3760 && ! no_input_reloads
&& ! no_output_reloads
3763 /* Similarly, make an optional reload for a pair of matching
3764 objects that are in MEM or a pseudo that didn't get a hard reg. */
3766 rtx operand
= recog_operand
[i
];
3768 while (GET_CODE (operand
) == SUBREG
)
3769 operand
= XEXP (operand
, 0);
3770 if ((GET_CODE (operand
) == MEM
3771 || (GET_CODE (operand
) == REG
3772 && REGNO (operand
) >= FIRST_PSEUDO_REGISTER
))
3773 && ((enum reg_class
) goal_alternative
[goal_alternative_matches
[i
]]
3775 operand_reloadnum
[i
] = operand_reloadnum
[goal_alternative_matches
[i
]]
3776 = push_reload (recog_operand
[goal_alternative_matches
[i
]],
3778 recog_operand_loc
[goal_alternative_matches
[i
]],
3779 recog_operand_loc
[i
],
3780 (enum reg_class
) goal_alternative
[goal_alternative_matches
[i
]],
3781 operand_mode
[goal_alternative_matches
[i
]],
3783 0, 1, goal_alternative_matches
[i
], RELOAD_OTHER
);
3786 /* If this insn pattern contains any MATCH_DUP's, make sure that
3787 they will be substituted if the operands they match are substituted.
3788 Also do now any substitutions we already did on the operands.
3790 Don't do this if we aren't making replacements because we might be
3791 propagating things allocated by frame pointer elimination into places
3792 it doesn't expect. */
3794 if (insn_code_number
>= 0 && replace
)
3795 for (i
= insn_n_dups
[insn_code_number
] - 1; i
>= 0; i
--)
3797 int opno
= recog_dup_num
[i
];
3798 *recog_dup_loc
[i
] = *recog_operand_loc
[opno
];
3799 if (operand_reloadnum
[opno
] >= 0)
3800 push_replacement (recog_dup_loc
[i
], operand_reloadnum
[opno
],
3801 insn_operand_mode
[insn_code_number
][opno
]);
3805 /* This loses because reloading of prior insns can invalidate the equivalence
3806 (or at least find_equiv_reg isn't smart enough to find it any more),
3807 causing this insn to need more reload regs than it needed before.
3808 It may be too late to make the reload regs available.
3809 Now this optimization is done safely in choose_reload_regs. */
3811 /* For each reload of a reg into some other class of reg,
3812 search for an existing equivalent reg (same value now) in the right class.
3813 We can use it as long as we don't need to change its contents. */
3814 for (i
= 0; i
< n_reloads
; i
++)
3815 if (reload_reg_rtx
[i
] == 0
3816 && reload_in
[i
] != 0
3817 && GET_CODE (reload_in
[i
]) == REG
3818 && reload_out
[i
] == 0)
3821 = find_equiv_reg (reload_in
[i
], insn
, reload_reg_class
[i
], -1,
3822 static_reload_reg_p
, 0, reload_inmode
[i
]);
3823 /* Prevent generation of insn to load the value
3824 because the one we found already has the value. */
3825 if (reload_reg_rtx
[i
])
3826 reload_in
[i
] = reload_reg_rtx
[i
];
3830 /* Perhaps an output reload can be combined with another
3831 to reduce needs by one. */
3832 if (!goal_earlyclobber
)
3835 /* If we have a pair of reloads for parts of an address, they are reloading
3836 the same object, the operands themselves were not reloaded, and they
3837 are for two operands that are supposed to match, merge the reloads and
3838 change the type of the surviving reload to RELOAD_FOR_OPERAND_ADDRESS. */
3840 for (i
= 0; i
< n_reloads
; i
++)
3844 for (j
= i
+ 1; j
< n_reloads
; j
++)
3845 if ((reload_when_needed
[i
] == RELOAD_FOR_INPUT_ADDRESS
3846 || reload_when_needed
[i
] == RELOAD_FOR_OUTPUT_ADDRESS
3847 || reload_when_needed
[i
] == RELOAD_FOR_INPADDR_ADDRESS
3848 || reload_when_needed
[i
] == RELOAD_FOR_OUTADDR_ADDRESS
)
3849 && (reload_when_needed
[j
] == RELOAD_FOR_INPUT_ADDRESS
3850 || reload_when_needed
[j
] == RELOAD_FOR_OUTPUT_ADDRESS
3851 || reload_when_needed
[j
] == RELOAD_FOR_INPADDR_ADDRESS
3852 || reload_when_needed
[j
] == RELOAD_FOR_OUTADDR_ADDRESS
)
3853 && rtx_equal_p (reload_in
[i
], reload_in
[j
])
3854 && (operand_reloadnum
[reload_opnum
[i
]] < 0
3855 || reload_optional
[operand_reloadnum
[reload_opnum
[i
]]])
3856 && (operand_reloadnum
[reload_opnum
[j
]] < 0
3857 || reload_optional
[operand_reloadnum
[reload_opnum
[j
]]])
3858 && (goal_alternative_matches
[reload_opnum
[i
]] == reload_opnum
[j
]
3859 || (goal_alternative_matches
[reload_opnum
[j
]]
3860 == reload_opnum
[i
])))
3862 for (k
= 0; k
< n_replacements
; k
++)
3863 if (replacements
[k
].what
== j
)
3864 replacements
[k
].what
= i
;
3866 if (reload_when_needed
[i
] == RELOAD_FOR_INPADDR_ADDRESS
3867 || reload_when_needed
[i
] == RELOAD_FOR_OUTADDR_ADDRESS
)
3868 reload_when_needed
[i
] = RELOAD_FOR_OPADDR_ADDR
;
3870 reload_when_needed
[i
] = RELOAD_FOR_OPERAND_ADDRESS
;
3875 /* Scan all the reloads and update their type.
3876 If a reload is for the address of an operand and we didn't reload
3877 that operand, change the type. Similarly, change the operand number
3878 of a reload when two operands match. If a reload is optional, treat it
3879 as though the operand isn't reloaded.
3881 ??? This latter case is somewhat odd because if we do the optional
3882 reload, it means the object is hanging around. Thus we need only
3883 do the address reload if the optional reload was NOT done.
3885 Change secondary reloads to be the address type of their operand, not
3888 If an operand's reload is now RELOAD_OTHER, change any
3889 RELOAD_FOR_INPUT_ADDRESS reloads of that operand to
3890 RELOAD_FOR_OTHER_ADDRESS. */
3892 for (i
= 0; i
< n_reloads
; i
++)
3894 if (reload_secondary_p
[i
]
3895 && reload_when_needed
[i
] == operand_type
[reload_opnum
[i
]])
3896 reload_when_needed
[i
] = address_type
[reload_opnum
[i
]];
3898 if ((reload_when_needed
[i
] == RELOAD_FOR_INPUT_ADDRESS
3899 || reload_when_needed
[i
] == RELOAD_FOR_OUTPUT_ADDRESS
3900 || reload_when_needed
[i
] == RELOAD_FOR_INPADDR_ADDRESS
3901 || reload_when_needed
[i
] == RELOAD_FOR_OUTADDR_ADDRESS
)
3902 && (operand_reloadnum
[reload_opnum
[i
]] < 0
3903 || reload_optional
[operand_reloadnum
[reload_opnum
[i
]]]))
3905 /* If we have a secondary reload to go along with this reload,
3906 change its type to RELOAD_FOR_OPADDR_ADDR. */
3908 if ((reload_when_needed
[i
] == RELOAD_FOR_INPUT_ADDRESS
3909 || reload_when_needed
[i
] == RELOAD_FOR_INPADDR_ADDRESS
)
3910 && reload_secondary_in_reload
[i
] != -1)
3912 int secondary_in_reload
= reload_secondary_in_reload
[i
];
3914 reload_when_needed
[secondary_in_reload
]
3915 = RELOAD_FOR_OPADDR_ADDR
;
3917 /* If there's a tertiary reload we have to change it also. */
3918 if (secondary_in_reload
> 0
3919 && reload_secondary_in_reload
[secondary_in_reload
] != -1)
3920 reload_when_needed
[reload_secondary_in_reload
[secondary_in_reload
]]
3921 = RELOAD_FOR_OPADDR_ADDR
;
3924 if ((reload_when_needed
[i
] == RELOAD_FOR_OUTPUT_ADDRESS
3925 || reload_when_needed
[i
] == RELOAD_FOR_OUTADDR_ADDRESS
)
3926 && reload_secondary_out_reload
[i
] != -1)
3928 int secondary_out_reload
= reload_secondary_out_reload
[i
];
3930 reload_when_needed
[secondary_out_reload
]
3931 = RELOAD_FOR_OPADDR_ADDR
;
3933 /* If there's a tertiary reload we have to change it also. */
3934 if (secondary_out_reload
3935 && reload_secondary_out_reload
[secondary_out_reload
] != -1)
3936 reload_when_needed
[reload_secondary_out_reload
[secondary_out_reload
]]
3937 = RELOAD_FOR_OPADDR_ADDR
;
3940 reload_when_needed
[i
] = RELOAD_FOR_OPERAND_ADDRESS
;
3943 if ((reload_when_needed
[i
] == RELOAD_FOR_INPUT_ADDRESS
3944 || reload_when_needed
[i
] == RELOAD_FOR_INPADDR_ADDRESS
)
3945 && operand_reloadnum
[reload_opnum
[i
]] >= 0
3946 && (reload_when_needed
[operand_reloadnum
[reload_opnum
[i
]]]
3948 reload_when_needed
[i
] = RELOAD_FOR_OTHER_ADDRESS
;
3950 if (goal_alternative_matches
[reload_opnum
[i
]] >= 0)
3951 reload_opnum
[i
] = goal_alternative_matches
[reload_opnum
[i
]];
3954 /* Scan all the reloads, and check for RELOAD_FOR_OPERAND_ADDRESS reloads.
3955 If we have more than one, then convert all RELOAD_FOR_OPADDR_ADDR
3956 reloads to RELOAD_FOR_OPERAND_ADDRESS reloads.
3958 choose_reload_regs assumes that RELOAD_FOR_OPADDR_ADDR reloads never
3959 conflict with RELOAD_FOR_OPERAND_ADDRESS reloads. This is true for a
3960 single pair of RELOAD_FOR_OPADDR_ADDR/RELOAD_FOR_OPERAND_ADDRESS reloads.
3961 However, if there is more than one RELOAD_FOR_OPERAND_ADDRESS reload,
3962 then a RELOAD_FOR_OPADDR_ADDR reload conflicts with all
3963 RELOAD_FOR_OPERAND_ADDRESS reloads other than the one that uses it.
3964 This is complicated by the fact that a single operand can have more
3965 than one RELOAD_FOR_OPERAND_ADDRESS reload. It is very difficult to fix
3966 choose_reload_regs without affecting code quality, and cases that
3967 actually fail are extremely rare, so it turns out to be better to fix
3968 the problem here by not generating cases that choose_reload_regs will
3972 int op_addr_reloads
= 0;
3973 for (i
= 0; i
< n_reloads
; i
++)
3974 if (reload_when_needed
[i
] == RELOAD_FOR_OPERAND_ADDRESS
)
3977 if (op_addr_reloads
> 1)
3978 for (i
= 0; i
< n_reloads
; i
++)
3979 if (reload_when_needed
[i
] == RELOAD_FOR_OPADDR_ADDR
)
3980 reload_when_needed
[i
] = RELOAD_FOR_OPERAND_ADDRESS
;
3983 /* See if we have any reloads that are now allowed to be merged
3984 because we've changed when the reload is needed to
3985 RELOAD_FOR_OPERAND_ADDRESS or RELOAD_FOR_OTHER_ADDRESS. Only
3986 check for the most common cases. */
3988 for (i
= 0; i
< n_reloads
; i
++)
3989 if (reload_in
[i
] != 0 && reload_out
[i
] == 0
3990 && (reload_when_needed
[i
] == RELOAD_FOR_OPERAND_ADDRESS
3991 || reload_when_needed
[i
] == RELOAD_FOR_OPADDR_ADDR
3992 || reload_when_needed
[i
] == RELOAD_FOR_OTHER_ADDRESS
))
3993 for (j
= 0; j
< n_reloads
; j
++)
3994 if (i
!= j
&& reload_in
[j
] != 0 && reload_out
[j
] == 0
3995 && reload_when_needed
[j
] == reload_when_needed
[i
]
3996 && MATCHES (reload_in
[i
], reload_in
[j
])
3997 && reload_reg_class
[i
] == reload_reg_class
[j
]
3998 && !reload_nocombine
[i
] && !reload_nocombine
[j
]
3999 && reload_reg_rtx
[i
] == reload_reg_rtx
[j
])
4001 reload_opnum
[i
] = MIN (reload_opnum
[i
], reload_opnum
[j
]);
4002 transfer_replacements (i
, j
);
4006 /* Set which reloads must use registers not used in any group. Start
4007 with those that conflict with a group and then include ones that
4008 conflict with ones that are already known to conflict with a group. */
4011 for (i
= 0; i
< n_reloads
; i
++)
4013 enum machine_mode mode
= reload_inmode
[i
];
4014 enum reg_class
class = reload_reg_class
[i
];
4017 if (GET_MODE_SIZE (reload_outmode
[i
]) > GET_MODE_SIZE (mode
))
4018 mode
= reload_outmode
[i
];
4019 size
= CLASS_MAX_NREGS (class, mode
);
4022 for (j
= 0; j
< n_reloads
; j
++)
4023 if ((CLASS_MAX_NREGS (reload_reg_class
[j
],
4024 (GET_MODE_SIZE (reload_outmode
[j
])
4025 > GET_MODE_SIZE (reload_inmode
[j
]))
4026 ? reload_outmode
[j
] : reload_inmode
[j
])
4028 && !reload_optional
[j
]
4029 && (reload_in
[j
] != 0 || reload_out
[j
] != 0
4030 || reload_secondary_p
[j
])
4031 && reloads_conflict (i
, j
)
4032 && reg_classes_intersect_p (class, reload_reg_class
[j
]))
4034 reload_nongroup
[i
] = 1;
4044 for (i
= 0; i
< n_reloads
; i
++)
4046 enum machine_mode mode
= reload_inmode
[i
];
4047 enum reg_class
class = reload_reg_class
[i
];
4050 if (GET_MODE_SIZE (reload_outmode
[i
]) > GET_MODE_SIZE (mode
))
4051 mode
= reload_outmode
[i
];
4052 size
= CLASS_MAX_NREGS (class, mode
);
4054 if (! reload_nongroup
[i
] && size
== 1)
4055 for (j
= 0; j
< n_reloads
; j
++)
4056 if (reload_nongroup
[j
]
4057 && reloads_conflict (i
, j
)
4058 && reg_classes_intersect_p (class, reload_reg_class
[j
]))
4060 reload_nongroup
[i
] = 1;
4067 #else /* no REGISTER_CONSTRAINTS */
4069 int insn_code_number
;
4070 int goal_earlyclobber
= 0; /* Always 0, to make combine_reloads happen. */
4072 rtx body
= PATTERN (insn
);
4076 n_earlyclobbers
= 0;
4077 replace_reloads
= replace
;
4080 /* Find what kind of insn this is. NOPERANDS gets number of operands.
4081 Store the operand values in RECOG_OPERAND and the locations
4082 of the words in the insn that point to them in RECOG_OPERAND_LOC.
4083 Return if the insn needs no reload processing. */
4085 switch (GET_CODE (body
))
4096 noperands
= asm_noperands (body
);
4099 /* This insn is an `asm' with operands.
4100 First, find out how many operands, and allocate space. */
4102 insn_code_number
= -1;
4103 /* ??? This is a bug! ???
4104 Give up and delete this insn if it has too many operands. */
4105 if (noperands
> MAX_RECOG_OPERANDS
)
4108 /* Now get the operand values out of the insn. */
4110 decode_asm_operands (body
, recog_operand
, recog_operand_loc
,
4111 NULL_PTR
, NULL_PTR
);
4116 /* Ordinary insn: recognize it, allocate space for operands and
4117 constraints, and get them out via insn_extract. */
4119 insn_code_number
= recog_memoized (insn
);
4120 noperands
= insn_n_operands
[insn_code_number
];
4121 insn_extract (insn
);
4127 for (i
= 0; i
< noperands
; i
++)
4129 register RTX_CODE code
= GET_CODE (recog_operand
[i
]);
4130 int is_set_dest
= GET_CODE (body
) == SET
&& (i
== 0);
4132 if (insn_code_number
>= 0)
4133 if (insn_operand_address_p
[insn_code_number
][i
])
4134 find_reloads_address (VOIDmode
, NULL_PTR
,
4135 recog_operand
[i
], recog_operand_loc
[i
],
4136 i
, RELOAD_FOR_INPUT
, ind_levels
, insn
);
4138 /* In these cases, we can't tell if the operand is an input
4139 or an output, so be conservative. In practice it won't be
4143 find_reloads_address (GET_MODE (recog_operand
[i
]),
4144 recog_operand_loc
[i
],
4145 XEXP (recog_operand
[i
], 0),
4146 &XEXP (recog_operand
[i
], 0),
4147 i
, RELOAD_OTHER
, ind_levels
, insn
);
4149 recog_operand
[i
] = *recog_operand_loc
[i
]
4150 = find_reloads_toplev (recog_operand
[i
], i
, RELOAD_OTHER
,
4151 ind_levels
, is_set_dest
);
4154 register int regno
= REGNO (recog_operand
[i
]);
4155 if (reg_equiv_constant
[regno
] != 0 && !is_set_dest
)
4156 recog_operand
[i
] = *recog_operand_loc
[i
]
4157 = reg_equiv_constant
[regno
];
4158 #if 0 /* This might screw code in reload1.c to delete prior output-reload
4159 that feeds this insn. */
4160 if (reg_equiv_mem
[regno
] != 0)
4161 recog_operand
[i
] = *recog_operand_loc
[i
]
4162 = reg_equiv_mem
[regno
];
4167 /* Perhaps an output reload can be combined with another
4168 to reduce needs by one. */
4169 if (!goal_earlyclobber
)
4171 #endif /* no REGISTER_CONSTRAINTS */
4174 /* Return 1 if alternative number ALTNUM in constraint-string CONSTRAINT
4175 accepts a memory operand with constant address. */
4178 alternative_allows_memconst (constraint
, altnum
)
4183 /* Skip alternatives before the one requested. */
4186 while (*constraint
++ != ',');
4189 /* Scan the requested alternative for 'm' or 'o'.
4190 If one of them is present, this alternative accepts memory constants. */
4191 while ((c
= *constraint
++) && c
!= ',' && c
!= '#')
4192 if (c
== 'm' || c
== 'o')
4197 /* Scan X for memory references and scan the addresses for reloading.
4198 Also checks for references to "constant" regs that we want to eliminate
4199 and replaces them with the values they stand for.
4200 We may alter X destructively if it contains a reference to such.
4201 If X is just a constant reg, we return the equivalent value
4204 IND_LEVELS says how many levels of indirect addressing this machine
4207 OPNUM and TYPE identify the purpose of the reload.
4209 IS_SET_DEST is true if X is the destination of a SET, which is not
4210 appropriate to be replaced by a constant. */
4213 find_reloads_toplev (x
, opnum
, type
, ind_levels
, is_set_dest
)
4216 enum reload_type type
;
4220 register RTX_CODE code
= GET_CODE (x
);
4222 register char *fmt
= GET_RTX_FORMAT (code
);
4227 /* This code is duplicated for speed in find_reloads. */
4228 register int regno
= REGNO (x
);
4229 if (reg_equiv_constant
[regno
] != 0 && !is_set_dest
)
4230 x
= reg_equiv_constant
[regno
];
4232 /* This creates (subreg (mem...)) which would cause an unnecessary
4233 reload of the mem. */
4234 else if (reg_equiv_mem
[regno
] != 0)
4235 x
= reg_equiv_mem
[regno
];
4237 else if (reg_equiv_address
[regno
] != 0)
4239 /* If reg_equiv_address varies, it may be shared, so copy it. */
4240 /* We must rerun eliminate_regs, in case the elimination
4241 offsets have changed. */
4242 rtx addr
= XEXP (eliminate_regs (reg_equiv_memory_loc
[regno
], 0,
4246 if (rtx_varies_p (addr
))
4247 addr
= copy_rtx (addr
);
4249 x
= gen_rtx_MEM (GET_MODE (x
), addr
);
4250 RTX_UNCHANGING_P (x
) = RTX_UNCHANGING_P (regno_reg_rtx
[regno
]);
4251 find_reloads_address (GET_MODE (x
), NULL_PTR
,
4253 &XEXP (x
, 0), opnum
, type
, ind_levels
, 0);
4260 find_reloads_address (GET_MODE (x
), &tem
, XEXP (x
, 0), &XEXP (x
, 0),
4261 opnum
, type
, ind_levels
, 0);
4265 if (code
== SUBREG
&& GET_CODE (SUBREG_REG (x
)) == REG
)
4267 /* Check for SUBREG containing a REG that's equivalent to a constant.
4268 If the constant has a known value, truncate it right now.
4269 Similarly if we are extracting a single-word of a multi-word
4270 constant. If the constant is symbolic, allow it to be substituted
4271 normally. push_reload will strip the subreg later. If the
4272 constant is VOIDmode, abort because we will lose the mode of
4273 the register (this should never happen because one of the cases
4274 above should handle it). */
4276 register int regno
= REGNO (SUBREG_REG (x
));
4279 if (subreg_lowpart_p (x
)
4280 && regno
>= FIRST_PSEUDO_REGISTER
&& reg_renumber
[regno
] < 0
4281 && reg_equiv_constant
[regno
] != 0
4282 && (tem
= gen_lowpart_common (GET_MODE (x
),
4283 reg_equiv_constant
[regno
])) != 0)
4286 if (GET_MODE_BITSIZE (GET_MODE (x
)) == BITS_PER_WORD
4287 && regno
>= FIRST_PSEUDO_REGISTER
&& reg_renumber
[regno
] < 0
4288 && reg_equiv_constant
[regno
] != 0
4289 && (tem
= operand_subword (reg_equiv_constant
[regno
],
4291 GET_MODE (SUBREG_REG (x
)))) != 0)
4294 /* If the SUBREG is wider than a word, the above test will fail.
4295 For example, we might have a SImode SUBREG of a DImode SUBREG_REG
4296 for a 16 bit target, or a DImode SUBREG of a TImode SUBREG_REG for
4297 a 32 bit target. We still can - and have to - handle this
4298 for non-paradoxical subregs of CONST_INTs. */
4299 if (regno
>= FIRST_PSEUDO_REGISTER
&& reg_renumber
[regno
] < 0
4300 && reg_equiv_constant
[regno
] != 0
4301 && GET_CODE (reg_equiv_constant
[regno
]) == CONST_INT
4302 && (GET_MODE_SIZE (GET_MODE (x
))
4303 < GET_MODE_SIZE (GET_MODE (SUBREG_REG (x
)))))
4305 int shift
= SUBREG_WORD (x
) * BITS_PER_WORD
;
4306 if (WORDS_BIG_ENDIAN
)
4307 shift
= (GET_MODE_BITSIZE (GET_MODE (SUBREG_REG (x
)))
4308 - GET_MODE_BITSIZE (GET_MODE (x
))
4310 /* Here we use the knowledge that CONST_INTs have a
4311 HOST_WIDE_INT field. */
4312 if (shift
>= HOST_BITS_PER_WIDE_INT
)
4313 shift
= HOST_BITS_PER_WIDE_INT
- 1;
4314 return GEN_INT (INTVAL (reg_equiv_constant
[regno
]) >> shift
);
4317 if (regno
>= FIRST_PSEUDO_REGISTER
&& reg_renumber
[regno
] < 0
4318 && reg_equiv_constant
[regno
] != 0
4319 && GET_MODE (reg_equiv_constant
[regno
]) == VOIDmode
)
4322 /* If the subreg contains a reg that will be converted to a mem,
4323 convert the subreg to a narrower memref now.
4324 Otherwise, we would get (subreg (mem ...) ...),
4325 which would force reload of the mem.
4327 We also need to do this if there is an equivalent MEM that is
4328 not offsettable. In that case, alter_subreg would produce an
4329 invalid address on big-endian machines.
4331 For machines that extend byte loads, we must not reload using
4332 a wider mode if we have a paradoxical SUBREG. find_reloads will
4333 force a reload in that case. So we should not do anything here. */
4335 else if (regno
>= FIRST_PSEUDO_REGISTER
4336 #ifdef LOAD_EXTEND_OP
4337 && (GET_MODE_SIZE (GET_MODE (x
))
4338 <= GET_MODE_SIZE (GET_MODE (SUBREG_REG (x
))))
4340 && (reg_equiv_address
[regno
] != 0
4341 || (reg_equiv_mem
[regno
] != 0
4342 && (! strict_memory_address_p (GET_MODE (x
),
4343 XEXP (reg_equiv_mem
[regno
], 0))
4344 || ! offsettable_memref_p (reg_equiv_mem
[regno
])))))
4346 int offset
= SUBREG_WORD (x
) * UNITS_PER_WORD
;
4347 /* We must rerun eliminate_regs, in case the elimination
4348 offsets have changed. */
4349 rtx addr
= XEXP (eliminate_regs (reg_equiv_memory_loc
[regno
], 0,
4352 if (BYTES_BIG_ENDIAN
)
4355 size
= GET_MODE_SIZE (GET_MODE (SUBREG_REG (x
)));
4356 offset
+= MIN (size
, UNITS_PER_WORD
);
4357 size
= GET_MODE_SIZE (GET_MODE (x
));
4358 offset
-= MIN (size
, UNITS_PER_WORD
);
4360 addr
= plus_constant (addr
, offset
);
4361 x
= gen_rtx_MEM (GET_MODE (x
), addr
);
4362 RTX_UNCHANGING_P (x
) = RTX_UNCHANGING_P (regno_reg_rtx
[regno
]);
4363 find_reloads_address (GET_MODE (x
), NULL_PTR
,
4365 &XEXP (x
, 0), opnum
, type
, ind_levels
, 0);
4370 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
4373 XEXP (x
, i
) = find_reloads_toplev (XEXP (x
, i
), opnum
, type
,
4374 ind_levels
, is_set_dest
);
4379 /* Return a mem ref for the memory equivalent of reg REGNO.
4380 This mem ref is not shared with anything. */
4383 make_memloc (ad
, regno
)
4390 /* We must rerun eliminate_regs, in case the elimination
4391 offsets have changed. */
4392 rtx tem
= XEXP (eliminate_regs (reg_equiv_memory_loc
[regno
], 0, NULL_RTX
), 0);
4394 #if 0 /* We cannot safely reuse a memloc made here;
4395 if the pseudo appears twice, and its mem needs a reload,
4396 it gets two separate reloads assigned, but it only
4397 gets substituted with the second of them;
4398 then it can get used before that reload reg gets loaded up. */
4399 for (i
= 0; i
< n_memlocs
; i
++)
4400 if (rtx_equal_p (tem
, XEXP (memlocs
[i
], 0)))
4404 /* If TEM might contain a pseudo, we must copy it to avoid
4405 modifying it when we do the substitution for the reload. */
4406 if (rtx_varies_p (tem
))
4407 tem
= copy_rtx (tem
);
4409 tem
= gen_rtx_MEM (GET_MODE (ad
), tem
);
4410 RTX_UNCHANGING_P (tem
) = RTX_UNCHANGING_P (regno_reg_rtx
[regno
]);
4411 memlocs
[n_memlocs
++] = tem
;
4415 /* Record all reloads needed for handling memory address AD
4416 which appears in *LOC in a memory reference to mode MODE
4417 which itself is found in location *MEMREFLOC.
4418 Note that we take shortcuts assuming that no multi-reg machine mode
4419 occurs as part of an address.
4421 OPNUM and TYPE specify the purpose of this reload.
4423 IND_LEVELS says how many levels of indirect addressing this machine
4426 INSN, if nonzero, is the insn in which we do the reload. It is used
4427 to determine if we may generate output reloads.
4429 Value is nonzero if this address is reloaded or replaced as a whole.
4430 This is interesting to the caller if the address is an autoincrement.
4432 Note that there is no verification that the address will be valid after
4433 this routine does its work. Instead, we rely on the fact that the address
4434 was valid when reload started. So we need only undo things that reload
4435 could have broken. These are wrong register types, pseudos not allocated
4436 to a hard register, and frame pointer elimination. */
4439 find_reloads_address (mode
, memrefloc
, ad
, loc
, opnum
, type
, ind_levels
, insn
)
4440 enum machine_mode mode
;
4445 enum reload_type type
;
4452 /* If the address is a register, see if it is a legitimate address and
4453 reload if not. We first handle the cases where we need not reload
4454 or where we must reload in a non-standard way. */
4456 if (GET_CODE (ad
) == REG
)
4460 if (reg_equiv_constant
[regno
] != 0
4461 && strict_memory_address_p (mode
, reg_equiv_constant
[regno
]))
4463 *loc
= ad
= reg_equiv_constant
[regno
];
4467 else if (reg_equiv_address
[regno
] != 0)
4469 tem
= make_memloc (ad
, regno
);
4470 find_reloads_address (GET_MODE (tem
), NULL_PTR
, XEXP (tem
, 0),
4471 &XEXP (tem
, 0), opnum
, ADDR_TYPE (type
),
4473 push_reload (tem
, NULL_RTX
, loc
, NULL_PTR
,
4474 reload_address_base_reg_class
,
4475 GET_MODE (ad
), VOIDmode
, 0, 0,
4480 /* We can avoid a reload if the register's equivalent memory expression
4481 is valid as an indirect memory address.
4482 But not all addresses are valid in a mem used as an indirect address:
4483 only reg or reg+constant. */
4485 else if (reg_equiv_mem
[regno
] != 0 && ind_levels
> 0
4486 && strict_memory_address_p (mode
, reg_equiv_mem
[regno
])
4487 && (GET_CODE (XEXP (reg_equiv_mem
[regno
], 0)) == REG
4488 || (GET_CODE (XEXP (reg_equiv_mem
[regno
], 0)) == PLUS
4489 && GET_CODE (XEXP (XEXP (reg_equiv_mem
[regno
], 0), 0)) == REG
4490 && CONSTANT_P (XEXP (XEXP (reg_equiv_mem
[regno
], 0), 1)))))
4493 /* The only remaining case where we can avoid a reload is if this is a
4494 hard register that is valid as a base register and which is not the
4495 subject of a CLOBBER in this insn. */
4497 else if (regno
< FIRST_PSEUDO_REGISTER
4498 && REGNO_MODE_OK_FOR_BASE_P (regno
, mode
)
4499 && ! regno_clobbered_p (regno
, this_insn
))
4502 /* If we do not have one of the cases above, we must do the reload. */
4503 push_reload (ad
, NULL_RTX
, loc
, NULL_PTR
, reload_address_base_reg_class
,
4504 GET_MODE (ad
), VOIDmode
, 0, 0, opnum
, type
);
4508 if (strict_memory_address_p (mode
, ad
))
4510 /* The address appears valid, so reloads are not needed.
4511 But the address may contain an eliminable register.
4512 This can happen because a machine with indirect addressing
4513 may consider a pseudo register by itself a valid address even when
4514 it has failed to get a hard reg.
4515 So do a tree-walk to find and eliminate all such regs. */
4517 /* But first quickly dispose of a common case. */
4518 if (GET_CODE (ad
) == PLUS
4519 && GET_CODE (XEXP (ad
, 1)) == CONST_INT
4520 && GET_CODE (XEXP (ad
, 0)) == REG
4521 && reg_equiv_constant
[REGNO (XEXP (ad
, 0))] == 0)
4524 subst_reg_equivs_changed
= 0;
4525 *loc
= subst_reg_equivs (ad
);
4527 if (! subst_reg_equivs_changed
)
4530 /* Check result for validity after substitution. */
4531 if (strict_memory_address_p (mode
, ad
))
4535 #ifdef LEGITIMIZE_RELOAD_ADDRESS
4540 LEGITIMIZE_RELOAD_ADDRESS (ad
, GET_MODE (*memrefloc
), opnum
, type
,
4545 *memrefloc
= copy_rtx (*memrefloc
);
4546 XEXP (*memrefloc
, 0) = ad
;
4547 move_replacements (&ad
, &XEXP (*memrefloc
, 0));
4553 /* The address is not valid. We have to figure out why. One possibility
4554 is that it is itself a MEM. This can happen when the frame pointer is
4555 being eliminated, a pseudo is not allocated to a hard register, and the
4556 offset between the frame and stack pointers is not its initial value.
4557 In that case the pseudo will have been replaced by a MEM referring to
4558 the stack pointer. */
4559 if (GET_CODE (ad
) == MEM
)
4561 /* First ensure that the address in this MEM is valid. Then, unless
4562 indirect addresses are valid, reload the MEM into a register. */
4564 find_reloads_address (GET_MODE (ad
), &tem
, XEXP (ad
, 0), &XEXP (ad
, 0),
4565 opnum
, ADDR_TYPE (type
),
4566 ind_levels
== 0 ? 0 : ind_levels
- 1, insn
);
4568 /* If tem was changed, then we must create a new memory reference to
4569 hold it and store it back into memrefloc. */
4570 if (tem
!= ad
&& memrefloc
)
4572 *memrefloc
= copy_rtx (*memrefloc
);
4573 copy_replacements (tem
, XEXP (*memrefloc
, 0));
4574 loc
= &XEXP (*memrefloc
, 0);
4577 /* Check similar cases as for indirect addresses as above except
4578 that we can allow pseudos and a MEM since they should have been
4579 taken care of above. */
4582 || (GET_CODE (XEXP (tem
, 0)) == SYMBOL_REF
&& ! indirect_symref_ok
)
4583 || GET_CODE (XEXP (tem
, 0)) == MEM
4584 || ! (GET_CODE (XEXP (tem
, 0)) == REG
4585 || (GET_CODE (XEXP (tem
, 0)) == PLUS
4586 && GET_CODE (XEXP (XEXP (tem
, 0), 0)) == REG
4587 && GET_CODE (XEXP (XEXP (tem
, 0), 1)) == CONST_INT
)))
4589 /* Must use TEM here, not AD, since it is the one that will
4590 have any subexpressions reloaded, if needed. */
4591 push_reload (tem
, NULL_RTX
, loc
, NULL_PTR
,
4592 reload_address_base_reg_class
, GET_MODE (tem
),
4601 /* If we have address of a stack slot but it's not valid because the
4602 displacement is too large, compute the sum in a register.
4603 Handle all base registers here, not just fp/ap/sp, because on some
4604 targets (namely SH) we can also get too large displacements from
4605 big-endian corrections. */
4606 else if (GET_CODE (ad
) == PLUS
4607 && GET_CODE (XEXP (ad
, 0)) == REG
4608 && REGNO (XEXP (ad
, 0)) < FIRST_PSEUDO_REGISTER
4609 && REG_MODE_OK_FOR_BASE_P (XEXP (ad
, 0), mode
)
4610 && GET_CODE (XEXP (ad
, 1)) == CONST_INT
)
4612 /* Unshare the MEM rtx so we can safely alter it. */
4615 *memrefloc
= copy_rtx (*memrefloc
);
4616 loc
= &XEXP (*memrefloc
, 0);
4618 if (double_reg_address_ok
)
4620 /* Unshare the sum as well. */
4621 *loc
= ad
= copy_rtx (ad
);
4622 /* Reload the displacement into an index reg.
4623 We assume the frame pointer or arg pointer is a base reg. */
4624 find_reloads_address_part (XEXP (ad
, 1), &XEXP (ad
, 1),
4625 reload_address_index_reg_class
,
4626 GET_MODE (ad
), opnum
, type
, ind_levels
);
4630 /* If the sum of two regs is not necessarily valid,
4631 reload the sum into a base reg.
4632 That will at least work. */
4633 find_reloads_address_part (ad
, loc
, reload_address_base_reg_class
,
4634 Pmode
, opnum
, type
, ind_levels
);
4639 /* If we have an indexed stack slot, there are three possible reasons why
4640 it might be invalid: The index might need to be reloaded, the address
4641 might have been made by frame pointer elimination and hence have a
4642 constant out of range, or both reasons might apply.
4644 We can easily check for an index needing reload, but even if that is the
4645 case, we might also have an invalid constant. To avoid making the
4646 conservative assumption and requiring two reloads, we see if this address
4647 is valid when not interpreted strictly. If it is, the only problem is
4648 that the index needs a reload and find_reloads_address_1 will take care
4651 There is still a case when we might generate an extra reload,
4652 however. In certain cases eliminate_regs will return a MEM for a REG
4653 (see the code there for details). In those cases, memory_address_p
4654 applied to our address will return 0 so we will think that our offset
4655 must be too large. But it might indeed be valid and the only problem
4656 is that a MEM is present where a REG should be. This case should be
4657 very rare and there doesn't seem to be any way to avoid it.
4659 If we decide to do something here, it must be that
4660 `double_reg_address_ok' is true and that this address rtl was made by
4661 eliminate_regs. We generate a reload of the fp/sp/ap + constant and
4662 rework the sum so that the reload register will be added to the index.
4663 This is safe because we know the address isn't shared.
4665 We check for fp/ap/sp as both the first and second operand of the
4668 else if (GET_CODE (ad
) == PLUS
&& GET_CODE (XEXP (ad
, 1)) == CONST_INT
4669 && GET_CODE (XEXP (ad
, 0)) == PLUS
4670 && (XEXP (XEXP (ad
, 0), 0) == frame_pointer_rtx
4671 #if FRAME_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
4672 || XEXP (XEXP (ad
, 0), 0) == hard_frame_pointer_rtx
4674 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4675 || XEXP (XEXP (ad
, 0), 0) == arg_pointer_rtx
4677 || XEXP (XEXP (ad
, 0), 0) == stack_pointer_rtx
)
4678 && ! memory_address_p (mode
, ad
))
4680 *loc
= ad
= gen_rtx_PLUS (GET_MODE (ad
),
4681 plus_constant (XEXP (XEXP (ad
, 0), 0),
4682 INTVAL (XEXP (ad
, 1))),
4683 XEXP (XEXP (ad
, 0), 1));
4684 find_reloads_address_part (XEXP (ad
, 0), &XEXP (ad
, 0),
4685 reload_address_base_reg_class
,
4686 GET_MODE (ad
), opnum
, type
, ind_levels
);
4687 find_reloads_address_1 (mode
, XEXP (ad
, 1), 1, &XEXP (ad
, 1), opnum
,
4693 else if (GET_CODE (ad
) == PLUS
&& GET_CODE (XEXP (ad
, 1)) == CONST_INT
4694 && GET_CODE (XEXP (ad
, 0)) == PLUS
4695 && (XEXP (XEXP (ad
, 0), 1) == frame_pointer_rtx
4696 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
4697 || XEXP (XEXP (ad
, 0), 1) == hard_frame_pointer_rtx
4699 #if FRAME_POINTER_REGNUM != ARG_POINTER_REGNUM
4700 || XEXP (XEXP (ad
, 0), 1) == arg_pointer_rtx
4702 || XEXP (XEXP (ad
, 0), 1) == stack_pointer_rtx
)
4703 && ! memory_address_p (mode
, ad
))
4705 *loc
= ad
= gen_rtx_PLUS (GET_MODE (ad
),
4706 XEXP (XEXP (ad
, 0), 0),
4707 plus_constant (XEXP (XEXP (ad
, 0), 1),
4708 INTVAL (XEXP (ad
, 1))));
4709 find_reloads_address_part (XEXP (ad
, 1), &XEXP (ad
, 1),
4710 reload_address_base_reg_class
,
4711 GET_MODE (ad
), opnum
, type
, ind_levels
);
4712 find_reloads_address_1 (mode
, XEXP (ad
, 0), 1, &XEXP (ad
, 0), opnum
,
4718 /* See if address becomes valid when an eliminable register
4719 in a sum is replaced. */
4722 if (GET_CODE (ad
) == PLUS
)
4723 tem
= subst_indexed_address (ad
);
4724 if (tem
!= ad
&& strict_memory_address_p (mode
, tem
))
4726 /* Ok, we win that way. Replace any additional eliminable
4729 subst_reg_equivs_changed
= 0;
4730 tem
= subst_reg_equivs (tem
);
4732 /* Make sure that didn't make the address invalid again. */
4734 if (! subst_reg_equivs_changed
|| strict_memory_address_p (mode
, tem
))
4741 /* If constants aren't valid addresses, reload the constant address
4743 if (CONSTANT_P (ad
) && ! strict_memory_address_p (mode
, ad
))
4745 /* If AD is in address in the constant pool, the MEM rtx may be shared.
4746 Unshare it so we can safely alter it. */
4747 if (memrefloc
&& GET_CODE (ad
) == SYMBOL_REF
4748 && CONSTANT_POOL_ADDRESS_P (ad
))
4750 *memrefloc
= copy_rtx (*memrefloc
);
4751 loc
= &XEXP (*memrefloc
, 0);
4754 find_reloads_address_part (ad
, loc
, reload_address_base_reg_class
,
4760 return find_reloads_address_1 (mode
, ad
, 0, loc
, opnum
, type
, ind_levels
,
4764 /* Find all pseudo regs appearing in AD
4765 that are eliminable in favor of equivalent values
4766 and do not have hard regs; replace them by their equivalents. */
4769 subst_reg_equivs (ad
)
4772 register RTX_CODE code
= GET_CODE (ad
);
4790 register int regno
= REGNO (ad
);
4792 if (reg_equiv_constant
[regno
] != 0)
4794 subst_reg_equivs_changed
= 1;
4795 return reg_equiv_constant
[regno
];
4801 /* Quickly dispose of a common case. */
4802 if (XEXP (ad
, 0) == frame_pointer_rtx
4803 && GET_CODE (XEXP (ad
, 1)) == CONST_INT
)
4811 fmt
= GET_RTX_FORMAT (code
);
4812 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
4814 XEXP (ad
, i
) = subst_reg_equivs (XEXP (ad
, i
));
4818 /* Compute the sum of X and Y, making canonicalizations assumed in an
4819 address, namely: sum constant integers, surround the sum of two
4820 constants with a CONST, put the constant as the second operand, and
4821 group the constant on the outermost sum.
4823 This routine assumes both inputs are already in canonical form. */
4830 enum machine_mode mode
= GET_MODE (x
);
4832 if (mode
== VOIDmode
)
4833 mode
= GET_MODE (y
);
4835 if (mode
== VOIDmode
)
4838 if (GET_CODE (x
) == CONST_INT
)
4839 return plus_constant (y
, INTVAL (x
));
4840 else if (GET_CODE (y
) == CONST_INT
)
4841 return plus_constant (x
, INTVAL (y
));
4842 else if (CONSTANT_P (x
))
4843 tem
= x
, x
= y
, y
= tem
;
4845 if (GET_CODE (x
) == PLUS
&& CONSTANT_P (XEXP (x
, 1)))
4846 return form_sum (XEXP (x
, 0), form_sum (XEXP (x
, 1), y
));
4848 /* Note that if the operands of Y are specified in the opposite
4849 order in the recursive calls below, infinite recursion will occur. */
4850 if (GET_CODE (y
) == PLUS
&& CONSTANT_P (XEXP (y
, 1)))
4851 return form_sum (form_sum (x
, XEXP (y
, 0)), XEXP (y
, 1));
4853 /* If both constant, encapsulate sum. Otherwise, just form sum. A
4854 constant will have been placed second. */
4855 if (CONSTANT_P (x
) && CONSTANT_P (y
))
4857 if (GET_CODE (x
) == CONST
)
4859 if (GET_CODE (y
) == CONST
)
4862 return gen_rtx_CONST (VOIDmode
, gen_rtx_PLUS (mode
, x
, y
));
4865 return gen_rtx_PLUS (mode
, x
, y
);
4868 /* If ADDR is a sum containing a pseudo register that should be
4869 replaced with a constant (from reg_equiv_constant),
4870 return the result of doing so, and also apply the associative
4871 law so that the result is more likely to be a valid address.
4872 (But it is not guaranteed to be one.)
4874 Note that at most one register is replaced, even if more are
4875 replaceable. Also, we try to put the result into a canonical form
4876 so it is more likely to be a valid address.
4878 In all other cases, return ADDR. */
4881 subst_indexed_address (addr
)
4884 rtx op0
= 0, op1
= 0, op2
= 0;
4888 if (GET_CODE (addr
) == PLUS
)
4890 /* Try to find a register to replace. */
4891 op0
= XEXP (addr
, 0), op1
= XEXP (addr
, 1), op2
= 0;
4892 if (GET_CODE (op0
) == REG
4893 && (regno
= REGNO (op0
)) >= FIRST_PSEUDO_REGISTER
4894 && reg_renumber
[regno
] < 0
4895 && reg_equiv_constant
[regno
] != 0)
4896 op0
= reg_equiv_constant
[regno
];
4897 else if (GET_CODE (op1
) == REG
4898 && (regno
= REGNO (op1
)) >= FIRST_PSEUDO_REGISTER
4899 && reg_renumber
[regno
] < 0
4900 && reg_equiv_constant
[regno
] != 0)
4901 op1
= reg_equiv_constant
[regno
];
4902 else if (GET_CODE (op0
) == PLUS
4903 && (tem
= subst_indexed_address (op0
)) != op0
)
4905 else if (GET_CODE (op1
) == PLUS
4906 && (tem
= subst_indexed_address (op1
)) != op1
)
4911 /* Pick out up to three things to add. */
4912 if (GET_CODE (op1
) == PLUS
)
4913 op2
= XEXP (op1
, 1), op1
= XEXP (op1
, 0);
4914 else if (GET_CODE (op0
) == PLUS
)
4915 op2
= op1
, op1
= XEXP (op0
, 1), op0
= XEXP (op0
, 0);
4917 /* Compute the sum. */
4919 op1
= form_sum (op1
, op2
);
4921 op0
= form_sum (op0
, op1
);
4928 /* Record the pseudo registers we must reload into hard registers in a
4929 subexpression of a would-be memory address, X referring to a value
4930 in mode MODE. (This function is not called if the address we find
4933 CONTEXT = 1 means we are considering regs as index regs,
4934 = 0 means we are considering them as base regs.
4936 OPNUM and TYPE specify the purpose of any reloads made.
4938 IND_LEVELS says how many levels of indirect addressing are
4939 supported at this point in the address.
4941 INSN, if nonzero, is the insn in which we do the reload. It is used
4942 to determine if we may generate output reloads.
4944 We return nonzero if X, as a whole, is reloaded or replaced. */
4946 /* Note that we take shortcuts assuming that no multi-reg machine mode
4947 occurs as part of an address.
4948 Also, this is not fully machine-customizable; it works for machines
4949 such as vaxes and 68000's and 32000's, but other possible machines
4950 could have addressing modes that this does not handle right. */
4953 find_reloads_address_1 (mode
, x
, context
, loc
, opnum
, type
, ind_levels
, insn
)
4954 enum machine_mode mode
;
4959 enum reload_type type
;
4963 register RTX_CODE code
= GET_CODE (x
);
4969 register rtx orig_op0
= XEXP (x
, 0);
4970 register rtx orig_op1
= XEXP (x
, 1);
4971 register RTX_CODE code0
= GET_CODE (orig_op0
);
4972 register RTX_CODE code1
= GET_CODE (orig_op1
);
4973 register rtx op0
= orig_op0
;
4974 register rtx op1
= orig_op1
;
4976 if (GET_CODE (op0
) == SUBREG
)
4978 op0
= SUBREG_REG (op0
);
4979 code0
= GET_CODE (op0
);
4980 if (code0
== REG
&& REGNO (op0
) < FIRST_PSEUDO_REGISTER
)
4981 op0
= gen_rtx_REG (word_mode
,
4982 REGNO (op0
) + SUBREG_WORD (orig_op0
));
4985 if (GET_CODE (op1
) == SUBREG
)
4987 op1
= SUBREG_REG (op1
);
4988 code1
= GET_CODE (op1
);
4989 if (code1
== REG
&& REGNO (op1
) < FIRST_PSEUDO_REGISTER
)
4990 op1
= gen_rtx_REG (GET_MODE (op1
),
4991 REGNO (op1
) + SUBREG_WORD (orig_op1
));
4994 if (code0
== MULT
|| code0
== SIGN_EXTEND
|| code0
== TRUNCATE
4995 || code0
== ZERO_EXTEND
|| code1
== MEM
)
4997 find_reloads_address_1 (mode
, orig_op0
, 1, &XEXP (x
, 0), opnum
,
4998 type
, ind_levels
, insn
);
4999 find_reloads_address_1 (mode
, orig_op1
, 0, &XEXP (x
, 1), opnum
,
5000 type
, ind_levels
, insn
);
5003 else if (code1
== MULT
|| code1
== SIGN_EXTEND
|| code1
== TRUNCATE
5004 || code1
== ZERO_EXTEND
|| code0
== MEM
)
5006 find_reloads_address_1 (mode
, orig_op0
, 0, &XEXP (x
, 0), opnum
,
5007 type
, ind_levels
, insn
);
5008 find_reloads_address_1 (mode
, orig_op1
, 1, &XEXP (x
, 1), opnum
,
5009 type
, ind_levels
, insn
);
5012 else if (code0
== CONST_INT
|| code0
== CONST
5013 || code0
== SYMBOL_REF
|| code0
== LABEL_REF
)
5014 find_reloads_address_1 (mode
, orig_op1
, 0, &XEXP (x
, 1), opnum
,
5015 type
, ind_levels
, insn
);
5017 else if (code1
== CONST_INT
|| code1
== CONST
5018 || code1
== SYMBOL_REF
|| code1
== LABEL_REF
)
5019 find_reloads_address_1 (mode
, orig_op0
, 0, &XEXP (x
, 0), opnum
,
5020 type
, ind_levels
, insn
);
5022 else if (code0
== REG
&& code1
== REG
)
5024 if (REG_OK_FOR_INDEX_P (op0
)
5025 && REG_MODE_OK_FOR_BASE_P (op1
, mode
))
5027 else if (REG_OK_FOR_INDEX_P (op1
)
5028 && REG_MODE_OK_FOR_BASE_P (op0
, mode
))
5030 else if (REG_MODE_OK_FOR_BASE_P (op1
, mode
))
5031 find_reloads_address_1 (mode
, orig_op0
, 1, &XEXP (x
, 0), opnum
,
5032 type
, ind_levels
, insn
);
5033 else if (REG_MODE_OK_FOR_BASE_P (op0
, mode
))
5034 find_reloads_address_1 (mode
, orig_op1
, 1, &XEXP (x
, 1), opnum
,
5035 type
, ind_levels
, insn
);
5036 else if (REG_OK_FOR_INDEX_P (op1
))
5037 find_reloads_address_1 (mode
, orig_op0
, 0, &XEXP (x
, 0), opnum
,
5038 type
, ind_levels
, insn
);
5039 else if (REG_OK_FOR_INDEX_P (op0
))
5040 find_reloads_address_1 (mode
, orig_op1
, 0, &XEXP (x
, 1), opnum
,
5041 type
, ind_levels
, insn
);
5044 find_reloads_address_1 (mode
, orig_op0
, 1, &XEXP (x
, 0), opnum
,
5045 type
, ind_levels
, insn
);
5046 find_reloads_address_1 (mode
, orig_op1
, 0, &XEXP (x
, 1), opnum
,
5047 type
, ind_levels
, insn
);
5051 else if (code0
== REG
)
5053 find_reloads_address_1 (mode
, orig_op0
, 1, &XEXP (x
, 0), opnum
,
5054 type
, ind_levels
, insn
);
5055 find_reloads_address_1 (mode
, orig_op1
, 0, &XEXP (x
, 1), opnum
,
5056 type
, ind_levels
, insn
);
5059 else if (code1
== REG
)
5061 find_reloads_address_1 (mode
, orig_op1
, 1, &XEXP (x
, 1), opnum
,
5062 type
, ind_levels
, insn
);
5063 find_reloads_address_1 (mode
, orig_op0
, 0, &XEXP (x
, 0), opnum
,
5064 type
, ind_levels
, insn
);
5074 if (GET_CODE (XEXP (x
, 0)) == REG
)
5076 register int regno
= REGNO (XEXP (x
, 0));
5080 /* A register that is incremented cannot be constant! */
5081 if (regno
>= FIRST_PSEUDO_REGISTER
5082 && reg_equiv_constant
[regno
] != 0)
5085 /* Handle a register that is equivalent to a memory location
5086 which cannot be addressed directly. */
5087 if (reg_equiv_address
[regno
] != 0)
5089 rtx tem
= make_memloc (XEXP (x
, 0), regno
);
5090 /* First reload the memory location's address.
5091 We can't use ADDR_TYPE (type) here, because we need to
5092 write back the value after reading it, hence we actually
5093 need two registers. */
5094 find_reloads_address (GET_MODE (tem
), 0, XEXP (tem
, 0),
5095 &XEXP (tem
, 0), opnum
, type
,
5097 /* Put this inside a new increment-expression. */
5098 x
= gen_rtx_fmt_e (GET_CODE (x
), GET_MODE (x
), tem
);
5099 /* Proceed to reload that, as if it contained a register. */
5102 /* If we have a hard register that is ok as an index,
5103 don't make a reload. If an autoincrement of a nice register
5104 isn't "valid", it must be that no autoincrement is "valid".
5105 If that is true and something made an autoincrement anyway,
5106 this must be a special context where one is allowed.
5107 (For example, a "push" instruction.)
5108 We can't improve this address, so leave it alone. */
5110 /* Otherwise, reload the autoincrement into a suitable hard reg
5111 and record how much to increment by. */
5113 if (reg_renumber
[regno
] >= 0)
5114 regno
= reg_renumber
[regno
];
5115 if ((regno
>= FIRST_PSEUDO_REGISTER
5116 || !(context
? REGNO_OK_FOR_INDEX_P (regno
)
5117 : REGNO_MODE_OK_FOR_BASE_P (regno
, mode
))))
5124 /* If we can output the register afterwards, do so, this
5125 saves the extra update.
5126 We can do so if we have an INSN - i.e. no JUMP_INSN nor
5127 CALL_INSN - and it does not set CC0.
5128 But don't do this if we cannot directly address the
5129 memory location, since this will make it harder to
5130 reuse address reloads, and increases register pressure.
5131 Also don't do this if we can probably update x directly. */
5132 rtx equiv
= reg_equiv_mem
[regno
];
5133 int icode
= (int) add_optab
->handlers
[(int) Pmode
].insn_code
;
5134 if (insn
&& GET_CODE (insn
) == INSN
&& equiv
5136 && ! sets_cc0_p (PATTERN (insn
))
5138 && ! (icode
!= CODE_FOR_nothing
5139 && (*insn_operand_predicate
[icode
][0]) (equiv
, Pmode
)
5140 && (*insn_operand_predicate
[icode
][1]) (equiv
, Pmode
)))
5145 = push_reload (x
, x
, loc
, loc
,
5147 ? reload_address_index_reg_class
5148 : reload_address_base_reg_class
),
5149 GET_MODE (x
), GET_MODE (x
), 0, 0,
5150 opnum
, RELOAD_OTHER
);
5155 = push_reload (x
, NULL_RTX
, loc
, NULL_PTR
,
5157 ? reload_address_index_reg_class
5158 : reload_address_base_reg_class
),
5159 GET_MODE (x
), GET_MODE (x
), 0, 0,
5161 reload_inc
[reloadnum
]
5162 = find_inc_amount (PATTERN (this_insn
), XEXP (x_orig
, 0));
5168 /* Update the REG_INC notes. */
5170 for (link
= REG_NOTES (this_insn
);
5171 link
; link
= XEXP (link
, 1))
5172 if (REG_NOTE_KIND (link
) == REG_INC
5173 && REGNO (XEXP (link
, 0)) == REGNO (XEXP (x_orig
, 0)))
5174 push_replacement (&XEXP (link
, 0), reloadnum
, VOIDmode
);
5180 else if (GET_CODE (XEXP (x
, 0)) == MEM
)
5182 /* This is probably the result of a substitution, by eliminate_regs,
5183 of an equivalent address for a pseudo that was not allocated to a
5184 hard register. Verify that the specified address is valid and
5185 reload it into a register. */
5186 rtx tem
= XEXP (x
, 0);
5190 /* Since we know we are going to reload this item, don't decrement
5191 for the indirection level.
5193 Note that this is actually conservative: it would be slightly
5194 more efficient to use the value of SPILL_INDIRECT_LEVELS from
5196 /* We can't use ADDR_TYPE (type) here, because we need to
5197 write back the value after reading it, hence we actually
5198 need two registers. */
5199 find_reloads_address (GET_MODE (x
), &XEXP (x
, 0),
5200 XEXP (XEXP (x
, 0), 0), &XEXP (XEXP (x
, 0), 0),
5201 opnum
, type
, ind_levels
, insn
);
5203 reloadnum
= push_reload (x
, NULL_RTX
, loc
, NULL_PTR
,
5205 ? reload_address_index_reg_class
5206 : reload_address_base_reg_class
),
5207 GET_MODE (x
), VOIDmode
, 0, 0, opnum
, type
);
5208 reload_inc
[reloadnum
]
5209 = find_inc_amount (PATTERN (this_insn
), XEXP (x
, 0));
5211 link
= FIND_REG_INC_NOTE (this_insn
, tem
);
5213 push_replacement (&XEXP (link
, 0), reloadnum
, VOIDmode
);
5220 /* This is probably the result of a substitution, by eliminate_regs, of
5221 an equivalent address for a pseudo that was not allocated to a hard
5222 register. Verify that the specified address is valid and reload it
5225 Since we know we are going to reload this item, don't decrement for
5226 the indirection level.
5228 Note that this is actually conservative: it would be slightly more
5229 efficient to use the value of SPILL_INDIRECT_LEVELS from
5232 find_reloads_address (GET_MODE (x
), loc
, XEXP (x
, 0), &XEXP (x
, 0),
5233 opnum
, ADDR_TYPE (type
), ind_levels
, insn
);
5234 push_reload (*loc
, NULL_RTX
, loc
, NULL_PTR
,
5235 (context
? reload_address_index_reg_class
5236 : reload_address_base_reg_class
),
5237 GET_MODE (x
), VOIDmode
, 0, 0, opnum
, type
);
5242 register int regno
= REGNO (x
);
5244 if (reg_equiv_constant
[regno
] != 0)
5246 find_reloads_address_part (reg_equiv_constant
[regno
], loc
,
5248 ? reload_address_index_reg_class
5249 : reload_address_base_reg_class
),
5250 GET_MODE (x
), opnum
, type
, ind_levels
);
5254 #if 0 /* This might screw code in reload1.c to delete prior output-reload
5255 that feeds this insn. */
5256 if (reg_equiv_mem
[regno
] != 0)
5258 push_reload (reg_equiv_mem
[regno
], NULL_RTX
, loc
, NULL_PTR
,
5260 ? reload_address_index_reg_class
5261 : reload_address_base_reg_class
),
5262 GET_MODE (x
), VOIDmode
, 0, 0, opnum
, type
);
5267 if (reg_equiv_address
[regno
] != 0)
5269 x
= make_memloc (x
, regno
);
5270 find_reloads_address (GET_MODE (x
), 0, XEXP (x
, 0), &XEXP (x
, 0),
5271 opnum
, ADDR_TYPE (type
), ind_levels
, insn
);
5274 if (reg_renumber
[regno
] >= 0)
5275 regno
= reg_renumber
[regno
];
5277 if ((regno
>= FIRST_PSEUDO_REGISTER
5278 || !(context
? REGNO_OK_FOR_INDEX_P (regno
)
5279 : REGNO_MODE_OK_FOR_BASE_P (regno
, mode
))))
5281 push_reload (x
, NULL_RTX
, loc
, NULL_PTR
,
5283 ? reload_address_index_reg_class
5284 : reload_address_base_reg_class
),
5285 GET_MODE (x
), VOIDmode
, 0, 0, opnum
, type
);
5289 /* If a register appearing in an address is the subject of a CLOBBER
5290 in this insn, reload it into some other register to be safe.
5291 The CLOBBER is supposed to make the register unavailable
5292 from before this insn to after it. */
5293 if (regno_clobbered_p (regno
, this_insn
))
5295 push_reload (x
, NULL_RTX
, loc
, NULL_PTR
,
5297 ? reload_address_index_reg_class
5298 : reload_address_base_reg_class
),
5299 GET_MODE (x
), VOIDmode
, 0, 0, opnum
, type
);
5306 if (GET_CODE (SUBREG_REG (x
)) == REG
)
5308 /* If this is a SUBREG of a hard register and the resulting register
5309 is of the wrong class, reload the whole SUBREG. This avoids
5310 needless copies if SUBREG_REG is multi-word. */
5311 if (REGNO (SUBREG_REG (x
)) < FIRST_PSEUDO_REGISTER
)
5313 int regno
= REGNO (SUBREG_REG (x
)) + SUBREG_WORD (x
);
5315 if (! (context
? REGNO_OK_FOR_INDEX_P (regno
)
5316 : REGNO_MODE_OK_FOR_BASE_P (regno
, mode
)))
5318 push_reload (x
, NULL_RTX
, loc
, NULL_PTR
,
5320 ? reload_address_index_reg_class
5321 : reload_address_base_reg_class
),
5322 GET_MODE (x
), VOIDmode
, 0, 0, opnum
, type
);
5326 /* If this is a SUBREG of a pseudo-register, and the pseudo-register
5327 is larger than the class size, then reload the whole SUBREG. */
5330 enum reg_class
class = (context
5331 ? reload_address_index_reg_class
5332 : reload_address_base_reg_class
);
5333 if (CLASS_MAX_NREGS (class, GET_MODE (SUBREG_REG (x
)))
5334 > reg_class_size
[class])
5336 push_reload (x
, NULL_RTX
, loc
, NULL_PTR
, class,
5337 GET_MODE (x
), VOIDmode
, 0, 0, opnum
, type
);
5349 register char *fmt
= GET_RTX_FORMAT (code
);
5352 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
5355 find_reloads_address_1 (mode
, XEXP (x
, i
), context
, &XEXP (x
, i
),
5356 opnum
, type
, ind_levels
, insn
);
5363 /* X, which is found at *LOC, is a part of an address that needs to be
5364 reloaded into a register of class CLASS. If X is a constant, or if
5365 X is a PLUS that contains a constant, check that the constant is a
5366 legitimate operand and that we are supposed to be able to load
5367 it into the register.
5369 If not, force the constant into memory and reload the MEM instead.
5371 MODE is the mode to use, in case X is an integer constant.
5373 OPNUM and TYPE describe the purpose of any reloads made.
5375 IND_LEVELS says how many levels of indirect addressing this machine
5379 find_reloads_address_part (x
, loc
, class, mode
, opnum
, type
, ind_levels
)
5382 enum reg_class
class;
5383 enum machine_mode mode
;
5385 enum reload_type type
;
5389 && (! LEGITIMATE_CONSTANT_P (x
)
5390 || PREFERRED_RELOAD_CLASS (x
, class) == NO_REGS
))
5392 rtx tem
= x
= force_const_mem (mode
, x
);
5393 find_reloads_address (mode
, &tem
, XEXP (tem
, 0), &XEXP (tem
, 0),
5394 opnum
, type
, ind_levels
, 0);
5397 else if (GET_CODE (x
) == PLUS
5398 && CONSTANT_P (XEXP (x
, 1))
5399 && (! LEGITIMATE_CONSTANT_P (XEXP (x
, 1))
5400 || PREFERRED_RELOAD_CLASS (XEXP (x
, 1), class) == NO_REGS
))
5402 rtx tem
= force_const_mem (GET_MODE (x
), XEXP (x
, 1));
5404 x
= gen_rtx_PLUS (GET_MODE (x
), XEXP (x
, 0), tem
);
5405 find_reloads_address (mode
, &tem
, XEXP (tem
, 0), &XEXP (tem
, 0),
5406 opnum
, type
, ind_levels
, 0);
5409 push_reload (x
, NULL_RTX
, loc
, NULL_PTR
, class,
5410 mode
, VOIDmode
, 0, 0, opnum
, type
);
5413 /* Substitute into the current INSN the registers into which we have reloaded
5414 the things that need reloading. The array `replacements'
5415 says contains the locations of all pointers that must be changed
5416 and says what to replace them with.
5418 Return the rtx that X translates into; usually X, but modified. */
5425 for (i
= 0; i
< n_replacements
; i
++)
5427 register struct replacement
*r
= &replacements
[i
];
5428 register rtx reloadreg
= reload_reg_rtx
[r
->what
];
5431 /* Encapsulate RELOADREG so its machine mode matches what
5432 used to be there. Note that gen_lowpart_common will
5433 do the wrong thing if RELOADREG is multi-word. RELOADREG
5434 will always be a REG here. */
5435 if (GET_MODE (reloadreg
) != r
->mode
&& r
->mode
!= VOIDmode
)
5436 reloadreg
= gen_rtx_REG (r
->mode
, REGNO (reloadreg
));
5438 /* If we are putting this into a SUBREG and RELOADREG is a
5439 SUBREG, we would be making nested SUBREGs, so we have to fix
5440 this up. Note that r->where == &SUBREG_REG (*r->subreg_loc). */
5442 if (r
->subreg_loc
!= 0 && GET_CODE (reloadreg
) == SUBREG
)
5444 if (GET_MODE (*r
->subreg_loc
)
5445 == GET_MODE (SUBREG_REG (reloadreg
)))
5446 *r
->subreg_loc
= SUBREG_REG (reloadreg
);
5449 *r
->where
= SUBREG_REG (reloadreg
);
5450 SUBREG_WORD (*r
->subreg_loc
) += SUBREG_WORD (reloadreg
);
5454 *r
->where
= reloadreg
;
5456 /* If reload got no reg and isn't optional, something's wrong. */
5457 else if (! reload_optional
[r
->what
])
5462 /* Make a copy of any replacements being done into X and move those copies
5463 to locations in Y, a copy of X. We only look at the highest level of
5467 copy_replacements (x
, y
)
5472 enum rtx_code code
= GET_CODE (x
);
5473 char *fmt
= GET_RTX_FORMAT (code
);
5474 struct replacement
*r
;
5476 /* We can't support X being a SUBREG because we might then need to know its
5477 location if something inside it was replaced. */
5481 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
5483 for (j
= 0; j
< n_replacements
; j
++)
5485 if (replacements
[j
].subreg_loc
== &XEXP (x
, i
))
5487 r
= &replacements
[n_replacements
++];
5488 r
->where
= replacements
[j
].where
;
5489 r
->subreg_loc
= &XEXP (y
, i
);
5490 r
->what
= replacements
[j
].what
;
5491 r
->mode
= replacements
[j
].mode
;
5493 else if (replacements
[j
].where
== &XEXP (x
, i
))
5495 r
= &replacements
[n_replacements
++];
5496 r
->where
= &XEXP (y
, i
);
5498 r
->what
= replacements
[j
].what
;
5499 r
->mode
= replacements
[j
].mode
;
5504 /* Change any replacements being done to *X to be done to *Y */
5507 move_replacements (x
, y
)
5513 for (i
= 0; i
< n_replacements
; i
++)
5514 if (replacements
[i
].subreg_loc
== x
)
5515 replacements
[i
].subreg_loc
= y
;
5516 else if (replacements
[i
].where
== x
)
5518 replacements
[i
].where
= y
;
5519 replacements
[i
].subreg_loc
= 0;
5523 /* If LOC was scheduled to be replaced by something, return the replacement.
5524 Otherwise, return *LOC. */
5527 find_replacement (loc
)
5530 struct replacement
*r
;
5532 for (r
= &replacements
[0]; r
< &replacements
[n_replacements
]; r
++)
5534 rtx reloadreg
= reload_reg_rtx
[r
->what
];
5536 if (reloadreg
&& r
->where
== loc
)
5538 if (r
->mode
!= VOIDmode
&& GET_MODE (reloadreg
) != r
->mode
)
5539 reloadreg
= gen_rtx_REG (r
->mode
, REGNO (reloadreg
));
5543 else if (reloadreg
&& r
->subreg_loc
== loc
)
5545 /* RELOADREG must be either a REG or a SUBREG.
5547 ??? Is it actually still ever a SUBREG? If so, why? */
5549 if (GET_CODE (reloadreg
) == REG
)
5550 return gen_rtx_REG (GET_MODE (*loc
),
5551 REGNO (reloadreg
) + SUBREG_WORD (*loc
));
5552 else if (GET_MODE (reloadreg
) == GET_MODE (*loc
))
5555 return gen_rtx_SUBREG (GET_MODE (*loc
), SUBREG_REG (reloadreg
),
5556 SUBREG_WORD (reloadreg
) + SUBREG_WORD (*loc
));
5560 /* If *LOC is a PLUS, MINUS, or MULT, see if a replacement is scheduled for
5561 what's inside and make a new rtl if so. */
5562 if (GET_CODE (*loc
) == PLUS
|| GET_CODE (*loc
) == MINUS
5563 || GET_CODE (*loc
) == MULT
)
5565 rtx x
= find_replacement (&XEXP (*loc
, 0));
5566 rtx y
= find_replacement (&XEXP (*loc
, 1));
5568 if (x
!= XEXP (*loc
, 0) || y
!= XEXP (*loc
, 1))
5569 return gen_rtx_fmt_ee (GET_CODE (*loc
), GET_MODE (*loc
), x
, y
);
5575 /* Return nonzero if register in range [REGNO, ENDREGNO)
5576 appears either explicitly or implicitly in X
5577 other than being stored into (except for earlyclobber operands).
5579 References contained within the substructure at LOC do not count.
5580 LOC may be zero, meaning don't ignore anything.
5582 This is similar to refers_to_regno_p in rtlanal.c except that we
5583 look at equivalences for pseudos that didn't get hard registers. */
5586 refers_to_regno_for_reload_p (regno
, endregno
, x
, loc
)
5587 int regno
, endregno
;
5592 register RTX_CODE code
;
5599 code
= GET_CODE (x
);
5606 /* If this is a pseudo, a hard register must not have been allocated.
5607 X must therefore either be a constant or be in memory. */
5608 if (i
>= FIRST_PSEUDO_REGISTER
)
5610 if (reg_equiv_memory_loc
[i
])
5611 return refers_to_regno_for_reload_p (regno
, endregno
,
5612 reg_equiv_memory_loc
[i
],
5615 if (reg_equiv_constant
[i
])
5621 return (endregno
> i
5622 && regno
< i
+ (i
< FIRST_PSEUDO_REGISTER
5623 ? HARD_REGNO_NREGS (i
, GET_MODE (x
))
5627 /* If this is a SUBREG of a hard reg, we can see exactly which
5628 registers are being modified. Otherwise, handle normally. */
5629 if (GET_CODE (SUBREG_REG (x
)) == REG
5630 && REGNO (SUBREG_REG (x
)) < FIRST_PSEUDO_REGISTER
)
5632 int inner_regno
= REGNO (SUBREG_REG (x
)) + SUBREG_WORD (x
);
5634 = inner_regno
+ (inner_regno
< FIRST_PSEUDO_REGISTER
5635 ? HARD_REGNO_NREGS (regno
, GET_MODE (x
)) : 1);
5637 return endregno
> inner_regno
&& regno
< inner_endregno
;
5643 if (&SET_DEST (x
) != loc
5644 /* Note setting a SUBREG counts as referring to the REG it is in for
5645 a pseudo but not for hard registers since we can
5646 treat each word individually. */
5647 && ((GET_CODE (SET_DEST (x
)) == SUBREG
5648 && loc
!= &SUBREG_REG (SET_DEST (x
))
5649 && GET_CODE (SUBREG_REG (SET_DEST (x
))) == REG
5650 && REGNO (SUBREG_REG (SET_DEST (x
))) >= FIRST_PSEUDO_REGISTER
5651 && refers_to_regno_for_reload_p (regno
, endregno
,
5652 SUBREG_REG (SET_DEST (x
)),
5654 /* If the output is an earlyclobber operand, this is
5656 || ((GET_CODE (SET_DEST (x
)) != REG
5657 || earlyclobber_operand_p (SET_DEST (x
)))
5658 && refers_to_regno_for_reload_p (regno
, endregno
,
5659 SET_DEST (x
), loc
))))
5662 if (code
== CLOBBER
|| loc
== &SET_SRC (x
))
5671 /* X does not match, so try its subexpressions. */
5673 fmt
= GET_RTX_FORMAT (code
);
5674 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
5676 if (fmt
[i
] == 'e' && loc
!= &XEXP (x
, i
))
5684 if (refers_to_regno_for_reload_p (regno
, endregno
,
5688 else if (fmt
[i
] == 'E')
5691 for (j
= XVECLEN (x
, i
) - 1; j
>=0; j
--)
5692 if (loc
!= &XVECEXP (x
, i
, j
)
5693 && refers_to_regno_for_reload_p (regno
, endregno
,
5694 XVECEXP (x
, i
, j
), loc
))
5701 /* Nonzero if modifying X will affect IN. If X is a register or a SUBREG,
5702 we check if any register number in X conflicts with the relevant register
5703 numbers. If X is a constant, return 0. If X is a MEM, return 1 iff IN
5704 contains a MEM (we don't bother checking for memory addresses that can't
5705 conflict because we expect this to be a rare case.
5707 This function is similar to reg_overlap_mention_p in rtlanal.c except
5708 that we look at equivalences for pseudos that didn't get hard registers. */
5711 reg_overlap_mentioned_for_reload_p (x
, in
)
5714 int regno
, endregno
;
5716 if (GET_CODE (x
) == SUBREG
)
5718 regno
= REGNO (SUBREG_REG (x
));
5719 if (regno
< FIRST_PSEUDO_REGISTER
)
5720 regno
+= SUBREG_WORD (x
);
5722 else if (GET_CODE (x
) == REG
)
5726 /* If this is a pseudo, it must not have been assigned a hard register.
5727 Therefore, it must either be in memory or be a constant. */
5729 if (regno
>= FIRST_PSEUDO_REGISTER
)
5731 if (reg_equiv_memory_loc
[regno
])
5732 return refers_to_mem_for_reload_p (in
);
5733 else if (reg_equiv_constant
[regno
])
5738 else if (CONSTANT_P (x
))
5740 else if (GET_CODE (x
) == MEM
)
5741 return refers_to_mem_for_reload_p (in
);
5742 else if (GET_CODE (x
) == SCRATCH
|| GET_CODE (x
) == PC
5743 || GET_CODE (x
) == CC0
)
5744 return reg_mentioned_p (x
, in
);
5748 endregno
= regno
+ (regno
< FIRST_PSEUDO_REGISTER
5749 ? HARD_REGNO_NREGS (regno
, GET_MODE (x
)) : 1);
5751 return refers_to_regno_for_reload_p (regno
, endregno
, in
, NULL_PTR
);
5754 /* Return nonzero if anything in X contains a MEM. Look also for pseudo
5758 refers_to_mem_for_reload_p (x
)
5764 if (GET_CODE (x
) == MEM
)
5767 if (GET_CODE (x
) == REG
)
5768 return (REGNO (x
) >= FIRST_PSEUDO_REGISTER
5769 && reg_equiv_memory_loc
[REGNO (x
)]);
5771 fmt
= GET_RTX_FORMAT (GET_CODE (x
));
5772 for (i
= GET_RTX_LENGTH (GET_CODE (x
)) - 1; i
>= 0; i
--)
5774 && (GET_CODE (XEXP (x
, i
)) == MEM
5775 || refers_to_mem_for_reload_p (XEXP (x
, i
))))
5781 /* Check the insns before INSN to see if there is a suitable register
5782 containing the same value as GOAL.
5783 If OTHER is -1, look for a register in class CLASS.
5784 Otherwise, just see if register number OTHER shares GOAL's value.
5786 Return an rtx for the register found, or zero if none is found.
5788 If RELOAD_REG_P is (short *)1,
5789 we reject any hard reg that appears in reload_reg_rtx
5790 because such a hard reg is also needed coming into this insn.
5792 If RELOAD_REG_P is any other nonzero value,
5793 it is a vector indexed by hard reg number
5794 and we reject any hard reg whose element in the vector is nonnegative
5795 as well as any that appears in reload_reg_rtx.
5797 If GOAL is zero, then GOALREG is a register number; we look
5798 for an equivalent for that register.
5800 MODE is the machine mode of the value we want an equivalence for.
5801 If GOAL is nonzero and not VOIDmode, then it must have mode MODE.
5803 This function is used by jump.c as well as in the reload pass.
5805 If GOAL is the sum of the stack pointer and a constant, we treat it
5806 as if it were a constant except that sp is required to be unchanging. */
5809 find_equiv_reg (goal
, insn
, class, other
, reload_reg_p
, goalreg
, mode
)
5812 enum reg_class
class;
5814 short *reload_reg_p
;
5816 enum machine_mode mode
;
5818 register rtx p
= insn
;
5819 rtx goaltry
, valtry
, value
, where
;
5821 register int regno
= -1;
5825 int goal_mem_addr_varies
= 0;
5826 int need_stable_sp
= 0;
5832 else if (GET_CODE (goal
) == REG
)
5833 regno
= REGNO (goal
);
5834 else if (GET_CODE (goal
) == MEM
)
5836 enum rtx_code code
= GET_CODE (XEXP (goal
, 0));
5837 if (MEM_VOLATILE_P (goal
))
5839 if (flag_float_store
&& GET_MODE_CLASS (GET_MODE (goal
)) == MODE_FLOAT
)
5841 /* An address with side effects must be reexecuted. */
5854 else if (CONSTANT_P (goal
))
5856 else if (GET_CODE (goal
) == PLUS
5857 && XEXP (goal
, 0) == stack_pointer_rtx
5858 && CONSTANT_P (XEXP (goal
, 1)))
5859 goal_const
= need_stable_sp
= 1;
5860 else if (GET_CODE (goal
) == PLUS
5861 && XEXP (goal
, 0) == frame_pointer_rtx
5862 && CONSTANT_P (XEXP (goal
, 1)))
5867 /* On some machines, certain regs must always be rejected
5868 because they don't behave the way ordinary registers do. */
5870 #ifdef OVERLAPPING_REGNO_P
5871 if (regno
>= 0 && regno
< FIRST_PSEUDO_REGISTER
5872 && OVERLAPPING_REGNO_P (regno
))
5876 /* Scan insns back from INSN, looking for one that copies
5877 a value into or out of GOAL.
5878 Stop and give up if we reach a label. */
5883 if (p
== 0 || GET_CODE (p
) == CODE_LABEL
)
5885 if (GET_CODE (p
) == INSN
5886 /* If we don't want spill regs ... */
5887 && (! (reload_reg_p
!= 0
5888 && reload_reg_p
!= (short *) (HOST_WIDE_INT
) 1)
5889 /* ... then ignore insns introduced by reload; they aren't useful
5890 and can cause results in reload_as_needed to be different
5891 from what they were when calculating the need for spills.
5892 If we notice an input-reload insn here, we will reject it below,
5893 but it might hide a usable equivalent. That makes bad code.
5894 It may even abort: perhaps no reg was spilled for this insn
5895 because it was assumed we would find that equivalent. */
5896 || INSN_UID (p
) < reload_first_uid
))
5899 pat
= single_set (p
);
5900 /* First check for something that sets some reg equal to GOAL. */
5903 && true_regnum (SET_SRC (pat
)) == regno
5904 && (valueno
= true_regnum (valtry
= SET_DEST (pat
))) >= 0)
5907 && true_regnum (SET_DEST (pat
)) == regno
5908 && (valueno
= true_regnum (valtry
= SET_SRC (pat
))) >= 0)
5910 (goal_const
&& rtx_equal_p (SET_SRC (pat
), goal
)
5911 && (valueno
= true_regnum (valtry
= SET_DEST (pat
))) >= 0)
5913 && (valueno
= true_regnum (valtry
= SET_DEST (pat
))) >= 0
5914 && rtx_renumbered_equal_p (goal
, SET_SRC (pat
)))
5916 && (valueno
= true_regnum (valtry
= SET_SRC (pat
))) >= 0
5917 && rtx_renumbered_equal_p (goal
, SET_DEST (pat
)))
5918 /* If we are looking for a constant,
5919 and something equivalent to that constant was copied
5920 into a reg, we can use that reg. */
5921 || (goal_const
&& (tem
= find_reg_note (p
, REG_EQUIV
,
5923 && rtx_equal_p (XEXP (tem
, 0), goal
)
5924 && (valueno
= true_regnum (valtry
= SET_DEST (pat
))) >= 0)
5925 || (goal_const
&& (tem
= find_reg_note (p
, REG_EQUIV
,
5927 && GET_CODE (SET_DEST (pat
)) == REG
5928 && GET_CODE (XEXP (tem
, 0)) == CONST_DOUBLE
5929 && GET_MODE_CLASS (GET_MODE (XEXP (tem
, 0))) == MODE_FLOAT
5930 && GET_CODE (goal
) == CONST_INT
5931 && 0 != (goaltry
= operand_subword (XEXP (tem
, 0), 0, 0,
5933 && rtx_equal_p (goal
, goaltry
)
5934 && (valtry
= operand_subword (SET_DEST (pat
), 0, 0,
5936 && (valueno
= true_regnum (valtry
)) >= 0)
5937 || (goal_const
&& (tem
= find_reg_note (p
, REG_EQUIV
,
5939 && GET_CODE (SET_DEST (pat
)) == REG
5940 && GET_CODE (XEXP (tem
, 0)) == CONST_DOUBLE
5941 && GET_MODE_CLASS (GET_MODE (XEXP (tem
, 0))) == MODE_FLOAT
5942 && GET_CODE (goal
) == CONST_INT
5943 && 0 != (goaltry
= operand_subword (XEXP (tem
, 0), 1, 0,
5945 && rtx_equal_p (goal
, goaltry
)
5947 = operand_subword (SET_DEST (pat
), 1, 0, VOIDmode
))
5948 && (valueno
= true_regnum (valtry
)) >= 0)))
5951 : ((unsigned) valueno
< FIRST_PSEUDO_REGISTER
5952 && TEST_HARD_REG_BIT (reg_class_contents
[(int) class],
5962 /* We found a previous insn copying GOAL into a suitable other reg VALUE
5963 (or copying VALUE into GOAL, if GOAL is also a register).
5964 Now verify that VALUE is really valid. */
5966 /* VALUENO is the register number of VALUE; a hard register. */
5968 /* Don't try to re-use something that is killed in this insn. We want
5969 to be able to trust REG_UNUSED notes. */
5970 if (find_reg_note (where
, REG_UNUSED
, value
))
5973 /* If we propose to get the value from the stack pointer or if GOAL is
5974 a MEM based on the stack pointer, we need a stable SP. */
5975 if (valueno
== STACK_POINTER_REGNUM
|| regno
== STACK_POINTER_REGNUM
5976 || (goal_mem
&& reg_overlap_mentioned_for_reload_p (stack_pointer_rtx
,
5980 /* Reject VALUE if the copy-insn moved the wrong sort of datum. */
5981 if (GET_MODE (value
) != mode
)
5984 /* Reject VALUE if it was loaded from GOAL
5985 and is also a register that appears in the address of GOAL. */
5987 if (goal_mem
&& value
== SET_DEST (single_set (where
))
5988 && refers_to_regno_for_reload_p (valueno
,
5990 + HARD_REGNO_NREGS (valueno
, mode
)),
5994 /* Reject registers that overlap GOAL. */
5996 if (!goal_mem
&& !goal_const
5997 && regno
+ HARD_REGNO_NREGS (regno
, mode
) > valueno
5998 && regno
< valueno
+ HARD_REGNO_NREGS (valueno
, mode
))
6001 /* Reject VALUE if it is one of the regs reserved for reloads.
6002 Reload1 knows how to reuse them anyway, and it would get
6003 confused if we allocated one without its knowledge.
6004 (Now that insns introduced by reload are ignored above,
6005 this case shouldn't happen, but I'm not positive.) */
6007 if (reload_reg_p
!= 0 && reload_reg_p
!= (short *) (HOST_WIDE_INT
) 1
6008 && reload_reg_p
[valueno
] >= 0)
6011 /* On some machines, certain regs must always be rejected
6012 because they don't behave the way ordinary registers do. */
6014 #ifdef OVERLAPPING_REGNO_P
6015 if (OVERLAPPING_REGNO_P (valueno
))
6019 nregs
= HARD_REGNO_NREGS (regno
, mode
);
6020 valuenregs
= HARD_REGNO_NREGS (valueno
, mode
);
6022 /* Reject VALUE if it is a register being used for an input reload
6023 even if it is not one of those reserved. */
6025 if (reload_reg_p
!= 0)
6028 for (i
= 0; i
< n_reloads
; i
++)
6029 if (reload_reg_rtx
[i
] != 0 && reload_in
[i
])
6031 int regno1
= REGNO (reload_reg_rtx
[i
]);
6032 int nregs1
= HARD_REGNO_NREGS (regno1
,
6033 GET_MODE (reload_reg_rtx
[i
]));
6034 if (regno1
< valueno
+ valuenregs
6035 && regno1
+ nregs1
> valueno
)
6041 /* We must treat frame pointer as varying here,
6042 since it can vary--in a nonlocal goto as generated by expand_goto. */
6043 goal_mem_addr_varies
= !CONSTANT_ADDRESS_P (XEXP (goal
, 0));
6045 /* Now verify that the values of GOAL and VALUE remain unaltered
6046 until INSN is reached. */
6055 /* Don't trust the conversion past a function call
6056 if either of the two is in a call-clobbered register, or memory. */
6057 if (GET_CODE (p
) == CALL_INSN
6058 && ((regno
>= 0 && regno
< FIRST_PSEUDO_REGISTER
6059 && call_used_regs
[regno
])
6061 (valueno
>= 0 && valueno
< FIRST_PSEUDO_REGISTER
6062 && call_used_regs
[valueno
])
6068 #ifdef NON_SAVING_SETJMP
6069 if (NON_SAVING_SETJMP
&& GET_CODE (p
) == NOTE
6070 && NOTE_LINE_NUMBER (p
) == NOTE_INSN_SETJMP
)
6074 #ifdef INSN_CLOBBERS_REGNO_P
6075 if ((valueno
>= 0 && valueno
< FIRST_PSEUDO_REGISTER
6076 && INSN_CLOBBERS_REGNO_P (p
, valueno
))
6077 || (regno
>= 0 && regno
< FIRST_PSEUDO_REGISTER
6078 && INSN_CLOBBERS_REGNO_P (p
, regno
)))
6082 if (GET_RTX_CLASS (GET_CODE (p
)) == 'i')
6084 /* If this insn P stores in either GOAL or VALUE, return 0.
6085 If GOAL is a memory ref and this insn writes memory, return 0.
6086 If GOAL is a memory ref and its address is not constant,
6087 and this insn P changes a register used in GOAL, return 0. */
6090 if (GET_CODE (pat
) == SET
|| GET_CODE (pat
) == CLOBBER
)
6092 register rtx dest
= SET_DEST (pat
);
6093 while (GET_CODE (dest
) == SUBREG
6094 || GET_CODE (dest
) == ZERO_EXTRACT
6095 || GET_CODE (dest
) == SIGN_EXTRACT
6096 || GET_CODE (dest
) == STRICT_LOW_PART
)
6097 dest
= XEXP (dest
, 0);
6098 if (GET_CODE (dest
) == REG
)
6100 register int xregno
= REGNO (dest
);
6102 if (REGNO (dest
) < FIRST_PSEUDO_REGISTER
)
6103 xnregs
= HARD_REGNO_NREGS (xregno
, GET_MODE (dest
));
6106 if (xregno
< regno
+ nregs
&& xregno
+ xnregs
> regno
)
6108 if (xregno
< valueno
+ valuenregs
6109 && xregno
+ xnregs
> valueno
)
6111 if (goal_mem_addr_varies
6112 && reg_overlap_mentioned_for_reload_p (dest
, goal
))
6115 else if (goal_mem
&& GET_CODE (dest
) == MEM
6116 && ! push_operand (dest
, GET_MODE (dest
)))
6118 else if (GET_CODE (dest
) == MEM
&& regno
>= FIRST_PSEUDO_REGISTER
6119 && reg_equiv_memory_loc
[regno
] != 0)
6121 else if (need_stable_sp
&& push_operand (dest
, GET_MODE (dest
)))
6124 else if (GET_CODE (pat
) == PARALLEL
)
6127 for (i
= XVECLEN (pat
, 0) - 1; i
>= 0; i
--)
6129 register rtx v1
= XVECEXP (pat
, 0, i
);
6130 if (GET_CODE (v1
) == SET
|| GET_CODE (v1
) == CLOBBER
)
6132 register rtx dest
= SET_DEST (v1
);
6133 while (GET_CODE (dest
) == SUBREG
6134 || GET_CODE (dest
) == ZERO_EXTRACT
6135 || GET_CODE (dest
) == SIGN_EXTRACT
6136 || GET_CODE (dest
) == STRICT_LOW_PART
)
6137 dest
= XEXP (dest
, 0);
6138 if (GET_CODE (dest
) == REG
)
6140 register int xregno
= REGNO (dest
);
6142 if (REGNO (dest
) < FIRST_PSEUDO_REGISTER
)
6143 xnregs
= HARD_REGNO_NREGS (xregno
, GET_MODE (dest
));
6146 if (xregno
< regno
+ nregs
6147 && xregno
+ xnregs
> regno
)
6149 if (xregno
< valueno
+ valuenregs
6150 && xregno
+ xnregs
> valueno
)
6152 if (goal_mem_addr_varies
6153 && reg_overlap_mentioned_for_reload_p (dest
,
6157 else if (goal_mem
&& GET_CODE (dest
) == MEM
6158 && ! push_operand (dest
, GET_MODE (dest
)))
6160 else if (GET_CODE (dest
) == MEM
&& regno
>= FIRST_PSEUDO_REGISTER
6161 && reg_equiv_memory_loc
[regno
] != 0)
6163 else if (need_stable_sp
6164 && push_operand (dest
, GET_MODE (dest
)))
6170 if (GET_CODE (p
) == CALL_INSN
&& CALL_INSN_FUNCTION_USAGE (p
))
6174 for (link
= CALL_INSN_FUNCTION_USAGE (p
); XEXP (link
, 1) != 0;
6175 link
= XEXP (link
, 1))
6177 pat
= XEXP (link
, 0);
6178 if (GET_CODE (pat
) == CLOBBER
)
6180 register rtx dest
= SET_DEST (pat
);
6181 while (GET_CODE (dest
) == SUBREG
6182 || GET_CODE (dest
) == ZERO_EXTRACT
6183 || GET_CODE (dest
) == SIGN_EXTRACT
6184 || GET_CODE (dest
) == STRICT_LOW_PART
)
6185 dest
= XEXP (dest
, 0);
6186 if (GET_CODE (dest
) == REG
)
6188 register int xregno
= REGNO (dest
);
6190 if (REGNO (dest
) < FIRST_PSEUDO_REGISTER
)
6191 xnregs
= HARD_REGNO_NREGS (xregno
, GET_MODE (dest
));
6194 if (xregno
< regno
+ nregs
6195 && xregno
+ xnregs
> regno
)
6197 if (xregno
< valueno
+ valuenregs
6198 && xregno
+ xnregs
> valueno
)
6200 if (goal_mem_addr_varies
6201 && reg_overlap_mentioned_for_reload_p (dest
,
6205 else if (goal_mem
&& GET_CODE (dest
) == MEM
6206 && ! push_operand (dest
, GET_MODE (dest
)))
6208 else if (need_stable_sp
6209 && push_operand (dest
, GET_MODE (dest
)))
6216 /* If this insn auto-increments or auto-decrements
6217 either regno or valueno, return 0 now.
6218 If GOAL is a memory ref and its address is not constant,
6219 and this insn P increments a register used in GOAL, return 0. */
6223 for (link
= REG_NOTES (p
); link
; link
= XEXP (link
, 1))
6224 if (REG_NOTE_KIND (link
) == REG_INC
6225 && GET_CODE (XEXP (link
, 0)) == REG
)
6227 register int incno
= REGNO (XEXP (link
, 0));
6228 if (incno
< regno
+ nregs
&& incno
>= regno
)
6230 if (incno
< valueno
+ valuenregs
&& incno
>= valueno
)
6232 if (goal_mem_addr_varies
6233 && reg_overlap_mentioned_for_reload_p (XEXP (link
, 0),
6243 /* Find a place where INCED appears in an increment or decrement operator
6244 within X, and return the amount INCED is incremented or decremented by.
6245 The value is always positive. */
6248 find_inc_amount (x
, inced
)
6251 register enum rtx_code code
= GET_CODE (x
);
6257 register rtx addr
= XEXP (x
, 0);
6258 if ((GET_CODE (addr
) == PRE_DEC
6259 || GET_CODE (addr
) == POST_DEC
6260 || GET_CODE (addr
) == PRE_INC
6261 || GET_CODE (addr
) == POST_INC
)
6262 && XEXP (addr
, 0) == inced
)
6263 return GET_MODE_SIZE (GET_MODE (x
));
6266 fmt
= GET_RTX_FORMAT (code
);
6267 for (i
= GET_RTX_LENGTH (code
) - 1; i
>= 0; i
--)
6271 register int tem
= find_inc_amount (XEXP (x
, i
), inced
);
6278 for (j
= XVECLEN (x
, i
) - 1; j
>= 0; j
--)
6280 register int tem
= find_inc_amount (XVECEXP (x
, i
, j
), inced
);
6290 /* Return 1 if register REGNO is the subject of a clobber in insn INSN. */
6293 regno_clobbered_p (regno
, insn
)
6297 if (GET_CODE (PATTERN (insn
)) == CLOBBER
6298 && GET_CODE (XEXP (PATTERN (insn
), 0)) == REG
)
6299 return REGNO (XEXP (PATTERN (insn
), 0)) == regno
;
6301 if (GET_CODE (PATTERN (insn
)) == PARALLEL
)
6303 int i
= XVECLEN (PATTERN (insn
), 0) - 1;
6307 rtx elt
= XVECEXP (PATTERN (insn
), 0, i
);
6308 if (GET_CODE (elt
) == CLOBBER
&& GET_CODE (XEXP (elt
, 0)) == REG
6309 && REGNO (XEXP (elt
, 0)) == regno
)
6317 static char *reload_when_needed_name
[] =
6320 "RELOAD_FOR_OUTPUT",
6322 "RELOAD_FOR_INPUT_ADDRESS",
6323 "RELOAD_FOR_INPADDR_ADDRESS",
6324 "RELOAD_FOR_OUTPUT_ADDRESS",
6325 "RELOAD_FOR_OUTADDR_ADDRESS",
6326 "RELOAD_FOR_OPERAND_ADDRESS",
6327 "RELOAD_FOR_OPADDR_ADDR",
6329 "RELOAD_FOR_OTHER_ADDRESS"
6332 static char *reg_class_names
[] = REG_CLASS_NAMES
;
6334 /* These functions are used to print the variables set by 'find_reloads' */
6337 debug_reload_to_stream (f
)
6345 for (r
= 0; r
< n_reloads
; r
++)
6347 fprintf (f
, "Reload %d: ", r
);
6349 if (reload_in
[r
] != 0)
6351 fprintf (f
, "reload_in (%s) = ",
6352 GET_MODE_NAME (reload_inmode
[r
]));
6353 print_inline_rtx (f
, reload_in
[r
], 24);
6354 fprintf (f
, "\n\t");
6357 if (reload_out
[r
] != 0)
6359 fprintf (f
, "reload_out (%s) = ",
6360 GET_MODE_NAME (reload_outmode
[r
]));
6361 print_inline_rtx (f
, reload_out
[r
], 24);
6362 fprintf (f
, "\n\t");
6365 fprintf (f
, "%s, ", reg_class_names
[(int) reload_reg_class
[r
]]);
6367 fprintf (f
, "%s (opnum = %d)",
6368 reload_when_needed_name
[(int) reload_when_needed
[r
]],
6371 if (reload_optional
[r
])
6372 fprintf (f
, ", optional");
6374 if (reload_nongroup
[r
])
6375 fprintf (stderr
, ", nongroup");
6377 if (reload_inc
[r
] != 0)
6378 fprintf (f
, ", inc by %d", reload_inc
[r
]);
6380 if (reload_nocombine
[r
])
6381 fprintf (f
, ", can't combine");
6383 if (reload_secondary_p
[r
])
6384 fprintf (f
, ", secondary_reload_p");
6386 if (reload_in_reg
[r
] != 0)
6388 fprintf (f
, "\n\treload_in_reg: ");
6389 print_inline_rtx (f
, reload_in_reg
[r
], 24);
6392 if (reload_reg_rtx
[r
] != 0)
6394 fprintf (f
, "\n\treload_reg_rtx: ");
6395 print_inline_rtx (f
, reload_reg_rtx
[r
], 24);
6399 if (reload_secondary_in_reload
[r
] != -1)
6401 fprintf (f
, "%ssecondary_in_reload = %d",
6402 prefix
, reload_secondary_in_reload
[r
]);
6406 if (reload_secondary_out_reload
[r
] != -1)
6407 fprintf (f
, "%ssecondary_out_reload = %d\n",
6408 prefix
, reload_secondary_out_reload
[r
]);
6411 if (reload_secondary_in_icode
[r
] != CODE_FOR_nothing
)
6413 fprintf (stderr
, "%ssecondary_in_icode = %s", prefix
,
6414 insn_name
[reload_secondary_in_icode
[r
]]);
6418 if (reload_secondary_out_icode
[r
] != CODE_FOR_nothing
)
6419 fprintf (stderr
, "%ssecondary_out_icode = %s", prefix
,
6420 insn_name
[reload_secondary_out_icode
[r
]]);
6429 debug_reload_to_stream (stderr
);