1/* Declarations for interface to insn recognizer and insn-output.cc.
2 Copyright (C) 1987-2024 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3. If not see
18<http://www.gnu.org/licenses/>. */
19
20#ifndef GCC_RECOG_H
21#define GCC_RECOG_H
22
23/* For enum tree_code ERROR_MARK. */
24#include "tree.h"
25
26/* Random number that should be large enough for all purposes. Also define
27 a type that has at least MAX_RECOG_ALTERNATIVES + 1 bits, with the extra
28 bit giving an invalid value that can be used to mean "uninitialized". */
29#define MAX_RECOG_ALTERNATIVES 35
30typedef uint64_t alternative_mask; /* Keep in sync with genattrtab.cc. */
31
32/* A mask of all alternatives. */
33#define ALL_ALTERNATIVES ((alternative_mask) -1)
34
35/* A mask containing just alternative X. */
36#define ALTERNATIVE_BIT(X) ((alternative_mask) 1 << (X))
37
38/* Types of operands. */
39enum op_type {
40 OP_IN,
41 OP_OUT,
42 OP_INOUT
43};
44
45#ifndef GENERATOR_FILE
46struct operand_alternative
47{
48 /* Pointer to the beginning of the constraint string for this alternative,
49 for easier access by alternative number. */
50 const char *constraint;
51
52 /* The register class valid for this alternative (possibly NO_REGS). */
53 ENUM_BITFIELD (reg_class) cl : 16;
54
55 /* "Badness" of this alternative, computed from number of '?' and '!'
56 characters in the constraint string. */
57 unsigned int reject : 16;
58
59 /* -1 if no matching constraint was found, or an operand number. */
60 int matches : 8;
61 /* The same information, but reversed: -1 if this operand is not
62 matched by any other, or the operand number of the operand that
63 matches this one. */
64 int matched : 8;
65
66 /* Bit ID is set if the constraint string includes a register constraint with
67 register filter ID. Use test_register_filters (REGISTER_FILTERS, REGNO)
68 to test whether REGNO is a valid start register for the operand. */
69 unsigned int register_filters : MAX (NUM_REGISTER_FILTERS, 1);
70
71 /* Nonzero if '&' was found in the constraint string. */
72 unsigned int earlyclobber : 1;
73 /* Nonzero if TARGET_MEM_CONSTRAINT was found in the constraint
74 string. */
75 unsigned int memory_ok : 1;
76 /* Nonzero if 'p' was found in the constraint string. */
77 unsigned int is_address : 1;
78 /* Nonzero if 'X' was found in the constraint string, or if the constraint
79 string for this alternative was empty. */
80 unsigned int anything_ok : 1;
81};
82
83/* Return the class for operand I of alternative ALT, taking matching
84 constraints into account. */
85
86inline enum reg_class
87alternative_class (const operand_alternative *alt, int i)
88{
89 return alt[i].matches >= 0 ? alt[alt[i].matches].cl : alt[i].cl;
90}
91
92/* Return the mask of register filters that should be applied to operand I
93 of alternative ALT, taking matching constraints into account. */
94
95inline unsigned int
96alternative_register_filters (const operand_alternative *alt, int i)
97{
98 return (alt[i].matches >= 0
99 ? alt[alt[i].matches].register_filters
100 : alt[i].register_filters);
101}
102#endif
103
104/* A class for substituting one rtx for another within an instruction,
105 or for recursively simplifying the instruction as-is. Derived classes
106 can record or filter certain decisions. */
107
108class insn_propagation : public simplify_context
109{
110public:
111 /* Assignments for RESULT_FLAGS.
112
113 UNSIMPLIFIED is true if a substitution has been made inside an rtx
114 X and if neither X nor its parent expressions could be simplified.
115
116 FIRST_SPARE_RESULT is the first flag available for derived classes. */
117 static const uint16_t UNSIMPLIFIED = 1U << 0;
118 static const uint16_t FIRST_SPARE_RESULT = 1U << 1;
119
120 insn_propagation (rtx_insn *);
121 insn_propagation (rtx_insn *, rtx, rtx, bool = true);
122 bool apply_to_pattern (rtx *);
123 bool apply_to_rvalue (rtx *);
124
125 /* Return true if we should accept a substitution into the address of
126 memory expression MEM. Undoing changes OLD_NUM_CHANGES and up restores
127 MEM's original address. */
128 virtual bool check_mem (int /*old_num_changes*/,
129 rtx /*mem*/) { return true; }
130
131 /* Note that we've simplified OLD_RTX into NEW_RTX. When substituting,
132 this only happens if a substitution occured within OLD_RTX.
133 Undoing OLD_NUM_CHANGES and up will restore the old form of OLD_RTX.
134 OLD_RESULT_FLAGS is the value that RESULT_FLAGS had before processing
135 OLD_RTX. */
136 virtual void note_simplification (int /*old_num_changes*/,
137 uint16_t /*old_result_flags*/,
138 rtx /*old_rtx*/, rtx /*new_rtx*/) {}
139
140private:
141 bool apply_to_mem_1 (rtx);
142 bool apply_to_lvalue_1 (rtx);
143 bool apply_to_rvalue_1 (rtx *);
144 bool apply_to_pattern_1 (rtx *);
145
146public:
147 /* The instruction that we are simplifying or propagating into. */
148 rtx_insn *insn;
149
150 /* If FROM is nonnull, we're replacing FROM with TO, otherwise we're
151 just doing a recursive simplification. */
152 rtx from;
153 rtx to;
154
155 /* The number of times that we have replaced FROM with TO. */
156 unsigned int num_replacements;
157
158 /* A bitmask of flags that describe the result of the simplificiation;
159 see above for details. */
160 uint16_t result_flags : 16;
161
162 /* True if we should unshare TO when making the next substitution,
163 false if we can use TO itself. */
164 uint16_t should_unshare : 1;
165
166 /* True if we should call check_mem after substituting into a memory. */
167 uint16_t should_check_mems : 1;
168
169 /* True if we should call note_simplification after each simplification. */
170 uint16_t should_note_simplifications : 1;
171
172 /* For future expansion. */
173 uint16_t spare : 13;
174
175 /* Gives the reason that a substitution failed, for debug purposes. */
176 const char *failure_reason;
177};
178
179/* Try to replace FROM with TO in INSN. SHARED_P is true if TO is shared
180 with other instructions, false if INSN can use TO directly. */
181
182inline insn_propagation::insn_propagation (rtx_insn *insn, rtx from, rtx to,
183 bool shared_p)
184 : insn (insn),
185 from (from),
186 to (to),
187 num_replacements (0),
188 result_flags (0),
189 should_unshare (shared_p),
190 should_check_mems (false),
191 should_note_simplifications (false),
192 spare (0),
193 failure_reason (nullptr)
194{
195}
196
197/* Try to simplify INSN without performing a substitution. */
198
199inline insn_propagation::insn_propagation (rtx_insn *insn)
200 : insn_propagation (insn, NULL_RTX, NULL_RTX)
201{
202}
203
204extern void init_recog (void);
205extern void init_recog_no_volatile (void);
206extern bool check_asm_operands (rtx);
207extern int asm_operand_ok (rtx, const char *, const char **);
208extern bool validate_change (rtx, rtx *, rtx, bool);
209extern bool validate_unshare_change (rtx, rtx *, rtx, bool);
210extern bool validate_change_xveclen (rtx, rtx *, int, bool);
211extern bool canonicalize_change_group (rtx_insn *insn, rtx x);
212extern bool insn_invalid_p (rtx_insn *, bool);
213extern bool verify_changes (int);
214extern void confirm_change_group (void);
215extern bool apply_change_group (void);
216extern int num_validated_changes (void);
217extern void cancel_changes (int);
218extern void temporarily_undo_changes (int);
219extern void redo_changes (int);
220extern bool constrain_operands (int, alternative_mask);
221extern bool constrain_operands_cached (rtx_insn *, int);
222extern bool memory_address_addr_space_p (machine_mode, rtx, addr_space_t,
223 code_helper = ERROR_MARK);
224#define memory_address_p(mode,addr) \
225 memory_address_addr_space_p ((mode), (addr), ADDR_SPACE_GENERIC)
226extern bool strict_memory_address_addr_space_p (machine_mode, rtx, addr_space_t,
227 code_helper = ERROR_MARK);
228#define strict_memory_address_p(mode,addr) \
229 strict_memory_address_addr_space_p ((mode), (addr), ADDR_SPACE_GENERIC)
230extern bool validate_replace_rtx_subexp (rtx, rtx, rtx_insn *, rtx *);
231extern bool validate_replace_rtx (rtx, rtx, rtx_insn *);
232extern bool validate_replace_rtx_part (rtx, rtx, rtx *, rtx_insn *);
233extern bool validate_replace_rtx_part_nosimplify (rtx, rtx, rtx *, rtx_insn *);
234extern void validate_replace_rtx_group (rtx, rtx, rtx_insn *);
235extern void validate_replace_src_group (rtx, rtx, rtx_insn *);
236extern bool validate_simplify_insn (rtx_insn *insn);
237extern int num_changes_pending (void);
238extern bool reg_fits_class_p (const_rtx, reg_class_t, int, machine_mode);
239extern bool valid_insn_p (rtx_insn *);
240
241extern bool offsettable_memref_p (rtx);
242extern bool offsettable_nonstrict_memref_p (rtx);
243extern bool offsettable_address_addr_space_p (int, machine_mode, rtx,
244 addr_space_t);
245#define offsettable_address_p(strict,mode,addr) \
246 offsettable_address_addr_space_p ((strict), (mode), (addr), \
247 ADDR_SPACE_GENERIC)
248extern bool mode_dependent_address_p (rtx, addr_space_t);
249
250extern int recog (rtx, rtx_insn *, int *);
251#ifndef GENERATOR_FILE
252inline int recog_memoized (rtx_insn *insn);
253#endif
254extern void add_clobbers (rtx, int);
255extern bool added_clobbers_hard_reg_p (int);
256extern void insn_extract (rtx_insn *);
257extern void extract_insn (rtx_insn *);
258extern void extract_constrain_insn (rtx_insn *insn);
259extern void extract_constrain_insn_cached (rtx_insn *);
260extern void extract_insn_cached (rtx_insn *);
261#ifndef GENERATOR_FILE
262extern void preprocess_constraints (int, int, const char **,
263 operand_alternative *, rtx **);
264extern const operand_alternative *preprocess_insn_constraints (unsigned int);
265#endif
266extern void preprocess_constraints (rtx_insn *);
267extern rtx_insn *peep2_next_insn (int);
268extern bool peep2_regno_dead_p (int, int);
269extern bool peep2_reg_dead_p (int, rtx);
270#ifdef HARD_CONST
271extern rtx peep2_find_free_register (int, int, const char *,
272 machine_mode, HARD_REG_SET *);
273#endif
274extern rtx_insn *peephole2_insns (rtx, rtx_insn *, int *);
275
276extern bool store_data_bypass_p (rtx_insn *, rtx_insn *);
277extern bool if_test_bypass_p (rtx_insn *, rtx_insn *);
278
279extern void copy_frame_info_to_split_insn (rtx_insn *, rtx_insn *);
280
281#ifndef GENERATOR_FILE
282/* Try recognizing the instruction INSN,
283 and return the code number that results.
284 Remember the code so that repeated calls do not
285 need to spend the time for actual rerecognition.
286
287 This function is the normal interface to instruction recognition.
288 The automatically-generated function `recog' is normally called
289 through this one. */
290
291inline int
292recog_memoized (rtx_insn *insn)
293{
294 if (INSN_CODE (insn) < 0)
295 INSN_CODE (insn) = recog (PATTERN (insn), insn, 0);
296 return INSN_CODE (insn);
297}
298#endif
299
300/* Skip chars until the next ',' or the end of the string. This is
301 useful to skip alternatives in a constraint string. */
302inline const char *
303skip_alternative (const char *p)
304{
305 const char *r = p;
306 while (*r != '\0' && *r != ',')
307 r++;
308 if (*r == ',')
309 r++;
310 return r;
311}
312
313/* Nonzero means volatile operands are recognized. */
314extern int volatile_ok;
315
316/* RAII class for temporarily setting volatile_ok. */
317
318class temporary_volatile_ok
319{
320public:
321 temporary_volatile_ok (int value) : save_volatile_ok (volatile_ok)
322 {
323 volatile_ok = value;
324 }
325
326 ~temporary_volatile_ok () { volatile_ok = save_volatile_ok; }
327
328private:
329 temporary_volatile_ok (const temporary_volatile_ok &);
330 int save_volatile_ok;
331};
332
333/* Set by constrain_operands to the number of the alternative that
334 matched. */
335extern int which_alternative;
336
337/* The following vectors hold the results from insn_extract. */
338
339struct recog_data_d
340{
341 /* It is very tempting to make the 5 operand related arrays into a
342 structure and index on that. However, to be source compatible
343 with all of the existing md file insn constraints and output
344 templates, we need `operand' as a flat array. Without that
345 member, making an array for the rest seems pointless. */
346
347 /* Gives value of operand N. */
348 rtx operand[MAX_RECOG_OPERANDS];
349
350 /* Gives location where operand N was found. */
351 rtx *operand_loc[MAX_RECOG_OPERANDS];
352
353 /* Gives the constraint string for operand N. */
354 const char *constraints[MAX_RECOG_OPERANDS];
355
356 /* Nonzero if operand N is a match_operator or a match_parallel. */
357 char is_operator[MAX_RECOG_OPERANDS];
358
359 /* Gives the mode of operand N. */
360 machine_mode operand_mode[MAX_RECOG_OPERANDS];
361
362 /* Gives the type (in, out, inout) for operand N. */
363 enum op_type operand_type[MAX_RECOG_OPERANDS];
364
365 /* Gives location where the Nth duplicate-appearance of an operand
366 was found. This is something that matched MATCH_DUP. */
367 rtx *dup_loc[MAX_DUP_OPERANDS];
368
369 /* Gives the operand number that was duplicated in the Nth
370 duplicate-appearance of an operand. */
371 char dup_num[MAX_DUP_OPERANDS];
372
373 /* ??? Note that these are `char' instead of `unsigned char' to (try to)
374 avoid certain lossage from K&R C, wherein `unsigned char' default
375 promotes to `unsigned int' instead of `int' as in ISO C. As of 1999,
376 the most common places to bootstrap from K&R C are SunOS and HPUX,
377 both of which have signed characters by default. The only other
378 supported natives that have both K&R C and unsigned characters are
379 ROMP and Irix 3, and neither have been seen for a while, but do
380 continue to consider unsignedness when performing arithmetic inside
381 a comparison. */
382
383 /* The number of operands of the insn. */
384 char n_operands;
385
386 /* The number of MATCH_DUPs in the insn. */
387 char n_dups;
388
389 /* The number of alternatives in the constraints for the insn. */
390 char n_alternatives;
391
392 /* True if insn is ASM_OPERANDS. */
393 bool is_asm;
394
395 /* In case we are caching, hold insn data was generated for. */
396 rtx_insn *insn;
397};
398
399extern struct recog_data_d recog_data;
400
401/* RAII class for saving/restoring recog_data. */
402
403class recog_data_saver
404{
405 recog_data_d m_saved_data;
406public:
407 recog_data_saver () : m_saved_data (recog_data) {}
408 ~recog_data_saver () { recog_data = m_saved_data; }
409};
410
411#ifndef GENERATOR_FILE
412extern const operand_alternative *recog_op_alt;
413
414/* Return a pointer to an array in which index OP describes the constraints
415 on operand OP of the current instruction alternative (which_alternative).
416 Only valid after calling preprocess_constraints and constrain_operands. */
417
418inline const operand_alternative *
419which_op_alt ()
420{
421 gcc_checking_assert (IN_RANGE (which_alternative, 0,
422 recog_data.n_alternatives - 1));
423 return &recog_op_alt[which_alternative * recog_data.n_operands];
424}
425#endif
426
427/* A table defined in insn-output.cc that give information about
428 each insn-code value. */
429
430typedef bool (*insn_operand_predicate_fn) (rtx, machine_mode);
431typedef const char * (*insn_output_fn) (rtx *, rtx_insn *);
432
433struct insn_gen_fn
434{
435 typedef void (*stored_funcptr) (void);
436
437 template<typename ...Ts>
438 rtx_insn *operator() (Ts... args) const
439 {
440 typedef rtx_insn *(*funcptr) (decltype ((void) args, NULL_RTX)...);
441 return ((funcptr) func) (args...);
442 }
443
444 // This is for compatibility of code that invokes functions like
445 // (*funcptr) (arg)
446 insn_gen_fn operator * (void) const { return *this; }
447
448 // The wrapped function pointer must be public and there must not be any
449 // constructors. Otherwise the insn_data_d struct initializers generated
450 // by genoutput.cc will result in static initializer functions, which defeats
451 // the purpose of the generated insn_data_d array.
452 stored_funcptr func;
453};
454
455struct insn_operand_data
456{
457 const insn_operand_predicate_fn predicate;
458
459 const char *const constraint;
460
461 ENUM_BITFIELD(machine_mode) const mode : 16;
462
463 const char strict_low;
464
465 const char is_operator;
466
467 const char eliminable;
468
469 const char allows_mem;
470};
471
472/* Legal values for insn_data.output_format. Indicate what type of data
473 is stored in insn_data.output. */
474#define INSN_OUTPUT_FORMAT_NONE 0 /* abort */
475#define INSN_OUTPUT_FORMAT_SINGLE 1 /* const char * */
476#define INSN_OUTPUT_FORMAT_MULTI 2 /* const char * const * */
477#define INSN_OUTPUT_FORMAT_FUNCTION 3 /* const char * (*)(...) */
478
479struct insn_data_d
480{
481 const char *const name;
482#if HAVE_DESIGNATED_UNION_INITIALIZERS
483 union {
484 const char *single;
485 const char *const *multi;
486 insn_output_fn function;
487 } output;
488#else
489 struct {
490 const char *single;
491 const char *const *multi;
492 insn_output_fn function;
493 } output;
494#endif
495 const insn_gen_fn genfun;
496 const struct insn_operand_data *const operand;
497
498 const char n_generator_args;
499 const char n_operands;
500 const char n_dups;
501 const char n_alternatives;
502 const char output_format;
503};
504
505extern const struct insn_data_d insn_data[];
506extern int peep2_current_count;
507
508#ifndef GENERATOR_FILE
509#include "insn-codes.h"
510
511/* An enum of boolean attributes that may only depend on the current
512 subtarget, not on things like operands or compiler phase. */
513enum bool_attr {
514 BA_ENABLED,
515 BA_PREFERRED_FOR_SPEED,
516 BA_PREFERRED_FOR_SIZE,
517 BA_LAST = BA_PREFERRED_FOR_SIZE
518};
519
520/* Target-dependent globals. */
521struct target_recog {
522 bool x_initialized;
523 alternative_mask x_bool_attr_masks[NUM_INSN_CODES][BA_LAST + 1];
524 operand_alternative *x_op_alt[NUM_INSN_CODES];
525};
526
527extern struct target_recog default_target_recog;
528#if SWITCHABLE_TARGET
529extern struct target_recog *this_target_recog;
530#else
531#define this_target_recog (&default_target_recog)
532#endif
533
534alternative_mask get_enabled_alternatives (rtx_insn *);
535alternative_mask get_preferred_alternatives (rtx_insn *);
536alternative_mask get_preferred_alternatives (rtx_insn *, basic_block);
537bool check_bool_attrs (rtx_insn *);
538
539void recog_init ();
540
541/* This RAII class can help to undo tentative insn changes on failure.
542 When an object of the class goes out of scope, it undoes all group
543 changes that have been made via the validate_change machinery and
544 not yet confirmed via confirm_change_group.
545
546 For example:
547
548 insn_change_watermark watermark;
549 validate_change (..., true); // A
550 ...
551 if (test)
552 // Undoes change A.
553 return false;
554 ...
555 validate_change (..., true); // B
556 ...
557 if (test)
558 // Undoes changes A and B.
559 return false;
560 ...
561 confirm_change_group ();
562
563 Code that wants to avoid this behavior can use keep ():
564
565 insn_change_watermark watermark;
566 validate_change (..., true); // A
567 ...
568 if (test)
569 // Undoes change A.
570 return false;
571 ...
572 watermark.keep ();
573 validate_change (..., true); // B
574 ...
575 if (test)
576 // Undoes change B, but not A.
577 return false;
578 ...
579 confirm_change_group (); */
580class insn_change_watermark
581{
582public:
583 insn_change_watermark () : m_old_num_changes (num_validated_changes ()) {}
584 ~insn_change_watermark ();
585 void keep () { m_old_num_changes = num_validated_changes (); }
586
587private:
588 int m_old_num_changes;
589};
590
591inline insn_change_watermark::~insn_change_watermark ()
592{
593 if (m_old_num_changes < num_validated_changes ())
594 cancel_changes (m_old_num_changes);
595}
596
597#endif
598
599#endif /* GCC_RECOG_H */
600

source code of gcc/recog.h