1 /* Generate code from machine description to recognize rtl as insns.
2 Copyright (C) 1987-1991 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, 675 Mass Ave, Cambridge, MA 02139, USA. */
21 /* This program is used to produce insn-recog.c, which contains
22 a function called `recog' plus its subroutines.
23 These functions contain a decision tree
24 that recognizes whether an rtx, the argument given to recog,
25 is a valid instruction.
27 recog returns -1 if the rtx is not valid.
28 If the rtx is valid, recog returns a nonnegative number
29 which is the insn code number for the pattern that matched.
30 This is the same as the order in the machine description of the
31 entry that matched. This number can be used as an index into various
32 insn_* tables, such as insn_template, insn_outfun, and insn_n_operands
33 (found in insn-output.c).
35 The third argument to recog is an optional pointer to an int.
36 If present, recog will accept a pattern if it matches except for
37 missing CLOBBER expressions at the end. In that case, the value
38 pointed to by the optional pointer will be set to the number of
39 CLOBBERs that need to be added (it should be initialized to zero by
40 the caller). If it is set nonzero, the caller should allocate a
41 PARALLEL of the appropriate size, copy the initial entries, and call
42 add_clobbers (found in insn-emit.c) to fill in the CLOBBERs.
44 This program also generates the function `split_insns',
45 which returns 0 if the rtl could not be split, or
46 it returns the split rtl in a SEQUENCE. */
53 static struct obstack obstack
;
54 struct obstack
*rtl_obstack
= &obstack
;
56 #define obstack_chunk_alloc xmalloc
57 #define obstack_chunk_free free
61 /* Data structure for a listhead of decision trees. The alternatives
62 to a node are kept in a doublely-linked list so we can easily add nodes
63 to the proper place when merging. */
65 struct decision_head
{ struct decision
*first
, *last
; };
67 /* Data structure for decision tree for recognizing
68 legitimate instructions. */
72 int number
; /* Node number, used for labels */
73 char *position
; /* String denoting position in pattern */
74 RTX_CODE code
; /* Code to test for or UNKNOWN to suppress */
75 char ignore_code
; /* If non-zero, need not test code */
76 char ignore_mode
; /* If non-zero, need not test mode */
77 int veclen
; /* Length of vector, if nonzero */
78 enum machine_mode mode
; /* Machine mode of node */
79 char enforce_mode
; /* If non-zero, test `mode' */
80 char retest_code
, retest_mode
; /* See write_tree_1 */
81 int test_elt_zero_int
; /* Nonzero if should test XINT (rtl, 0) */
82 int elt_zero_int
; /* Required value for XINT (rtl, 0) */
83 int test_elt_one_int
; /* Nonzero if should test XINT (rtl, 1) */
84 int elt_one_int
; /* Required value for XINT (rtl, 2) */
85 char *tests
; /* If nonzero predicate to call */
86 int pred
; /* `preds' index of predicate or -1 */
87 char *c_test
; /* Additional test to perform */
88 struct decision_head success
; /* Nodes to test on success */
89 int insn_code_number
; /* Insn number matched, if success */
90 int num_clobbers_to_add
; /* Number of CLOBBERs to be added to pattern */
91 struct decision
*next
; /* Node to test on failure */
92 struct decision
*prev
; /* Node whose failure tests us */
93 struct decision
*afterward
; /* Node to test on success, but failure of
95 int opno
; /* Operand number, if >= 0 */
96 int dupno
; /* Number of operand to compare against */
97 int label_needed
; /* Nonzero if label needed when writing tree */
98 int subroutine_number
; /* Number of subroutine this node starts */
101 #define SUBROUTINE_THRESHOLD 50
103 static int next_subroutine_number
;
105 /* We can write two types of subroutines: One for insn recognition and
106 one to split insns. This defines which type is being written. */
108 enum routine_type
{RECOG
, SPLIT
};
110 /* Next available node number for tree nodes. */
112 static int next_number
;
114 /* Next number to use as an insn_code. */
116 static int next_insn_code
;
118 /* Similar, but counts all expressions in the MD file; used for
121 static int next_index
;
123 /* Record the highest depth we ever have so we know how many variables to
124 allocate in each subroutine we make. */
126 static int max_depth
;
128 /* This table contains a list of the rtl codes that can possibly match a
129 predicate defined in recog.c. The function `not_both_true' uses it to
130 deduce that there are no expressions that can be matches by certain pairs
131 of tree nodes. Also, if a predicate can match only one code, we can
132 hardwire that code into the node testing the predicate. */
134 static struct pred_table
137 RTX_CODE codes
[NUM_RTX_CODE
];
139 = {{"general_operand", {CONST_INT
, CONST_DOUBLE
, CONST
, SYMBOL_REF
,
140 LABEL_REF
, SUBREG
, REG
, MEM
}},
141 #ifdef PREDICATE_CODES
144 {"address_operand", {CONST_INT
, CONST_DOUBLE
, CONST
, SYMBOL_REF
,
145 LABEL_REF
, SUBREG
, REG
, MEM
, PLUS
, MINUS
, MULT
}},
146 {"register_operand", {SUBREG
, REG
}},
147 {"scratch_operand", {SCRATCH
, REG
}},
148 {"immediate_operand", {CONST_INT
, CONST_DOUBLE
, CONST
, SYMBOL_REF
,
150 {"const_int_operand", {CONST_INT
}},
151 {"const_double_operand", {CONST_INT
, CONST_DOUBLE
}},
152 {"nonimmediate_operand", {SUBREG
, REG
, MEM
}},
153 {"nonmemory_operand", {CONST_INT
, CONST_DOUBLE
, CONST
, SYMBOL_REF
,
154 LABEL_REF
, SUBREG
, REG
}},
155 {"push_operand", {MEM
}},
156 {"memory_operand", {SUBREG
, MEM
}},
157 {"indirect_operand", {SUBREG
, MEM
}},
158 {"comparison_operation", {EQ
, NE
, LE
, LT
, GE
, LT
, LEU
, LTU
, GEU
, GTU
}},
159 {"mode_independent_operand", {CONST_INT
, CONST_DOUBLE
, CONST
, SYMBOL_REF
,
160 LABEL_REF
, SUBREG
, REG
, MEM
}}};
162 #define NUM_KNOWN_PREDS (sizeof preds / sizeof preds[0])
164 static int try_merge_1 ();
165 static int no_same_mode ();
166 static int same_codes ();
167 static int same_modes ();
169 static struct decision
*add_to_sequence ();
170 static struct decision_head
merge_trees ();
171 static struct decision
*try_merge_2 ();
172 static void write_subroutine ();
173 static void print_code ();
174 static void clear_codes ();
175 static void clear_modes ();
176 static void change_state ();
177 static void write_tree ();
178 static char *copystr ();
179 static char *concat ();
180 static void fatal ();
182 static void mybzero ();
183 static void mybcopy ();
185 /* Construct and return a sequence of decisions
186 that will recognize INSN.
188 TYPE says what type of routine we are recognizing (RECOG or SPLIT). */
190 static struct decision_head
191 make_insn_sequence (insn
, type
)
193 enum routine_type type
;
196 char *c_test
= XSTR (insn
, type
== RECOG
? 2 : 1);
197 struct decision
*last
;
198 struct decision_head head
;
200 if (XVECLEN (insn
, type
== RECOG
) == 1)
201 x
= XVECEXP (insn
, type
== RECOG
, 0);
204 x
= rtx_alloc (PARALLEL
);
205 XVEC (x
, 0) = XVEC (insn
, type
== RECOG
);
206 PUT_MODE (x
, VOIDmode
);
209 last
= add_to_sequence (x
, &head
, "");
212 last
->c_test
= c_test
;
213 last
->insn_code_number
= next_insn_code
;
214 last
->num_clobbers_to_add
= 0;
216 /* If this is not a DEFINE_SPLIT and X is a PARALLEL, see if it ends with a
217 group of CLOBBERs of (hard) registers or MATCH_SCRATCHes. If so, set up
218 to recognize the pattern without these CLOBBERs. */
220 if (type
== RECOG
&& GET_CODE (x
) == PARALLEL
)
224 for (i
= XVECLEN (x
, 0); i
> 0; i
--)
225 if (GET_CODE (XVECEXP (x
, 0, i
- 1)) != CLOBBER
226 || (GET_CODE (XEXP (XVECEXP (x
, 0, i
- 1), 0)) != REG
227 && GET_CODE (XEXP (XVECEXP (x
, 0, i
- 1), 0)) != MATCH_SCRATCH
))
230 if (i
!= XVECLEN (x
, 0))
233 struct decision_head clobber_head
;
236 new = XVECEXP (x
, 0, 0);
241 new = rtx_alloc (PARALLEL
);
242 XVEC (new, 0) = rtvec_alloc (i
);
243 for (j
= i
- 1; j
>= 0; j
--)
244 XVECEXP (new, 0, j
) = XVECEXP (x
, 0, j
);
247 last
= add_to_sequence (new, &clobber_head
, "");
250 last
->c_test
= c_test
;
251 last
->insn_code_number
= next_insn_code
;
252 last
->num_clobbers_to_add
= XVECLEN (x
, 0) - i
;
254 head
= merge_trees (head
, clobber_head
);
261 /* Define the subroutine we will call below and emit in genemit. */
262 printf ("extern rtx gen_split_%d ();\n", last
->insn_code_number
);
267 /* Create a chain of nodes to verify that an rtl expression matches
270 LAST is a pointer to the listhead in the previous node in the chain (or
271 in the calling function, for the first node).
273 POSITION is the string representing the current position in the insn.
275 A pointer to the final node in the chain is returned. */
277 static struct decision
*
278 add_to_sequence (pattern
, last
, position
)
280 struct decision_head
*last
;
283 register RTX_CODE code
;
284 register struct decision
*new
285 = (struct decision
*) xmalloc (sizeof (struct decision
));
286 struct decision
*this;
290 int depth
= strlen (position
);
293 if (depth
> max_depth
)
296 new->number
= next_number
++;
297 new->position
= copystr (position
);
298 new->ignore_code
= 0;
299 new->ignore_mode
= 0;
300 new->enforce_mode
= 1;
301 new->retest_code
= new->retest_mode
= 0;
303 new->test_elt_zero_int
= 0;
304 new->test_elt_one_int
= 0;
305 new->elt_zero_int
= 0;
306 new->elt_one_int
= 0;
310 new->success
.first
= new->success
.last
= 0;
311 new->insn_code_number
= -1;
312 new->num_clobbers_to_add
= 0;
318 new->label_needed
= 0;
319 new->subroutine_number
= 0;
323 last
->first
= last
->last
= new;
325 newpos
= (char *) alloca (depth
+ 2);
326 strcpy (newpos
, position
);
327 newpos
[depth
+ 1] = 0;
331 new->mode
= GET_MODE (pattern
);
332 new->code
= code
= GET_CODE (pattern
);
340 new->opno
= XINT (pattern
, 0);
341 new->code
= (code
== MATCH_PARALLEL
? PARALLEL
: UNKNOWN
);
342 new->enforce_mode
= 0;
344 if (code
== MATCH_SCRATCH
)
345 new->tests
= "scratch_operand";
347 new->tests
= XSTR (pattern
, 1);
349 if (*new->tests
== 0)
352 /* See if we know about this predicate and save its number. If we do,
353 and it only accepts one code, note that fact. The predicate
354 `const_int_operand' only tests for a CONST_INT, so if we do so we
355 can avoid calling it at all.
357 Finally, if we know that the predicate does not allow CONST_INT, we
358 know that the only way the predicate can match is if the modes match
359 (here we use the kluge of relying on the fact that "address_operand"
360 accepts CONST_INT; otherwise, it would have to be a special case),
361 so we can test the mode (but we need not). This fact should
362 considerably simplify the generated code. */
365 for (i
= 0; i
< NUM_KNOWN_PREDS
; i
++)
366 if (! strcmp (preds
[i
].name
, new->tests
))
369 int allows_const_int
= 0;
373 if (preds
[i
].codes
[1] == 0 && new->code
== UNKNOWN
)
375 new->code
= preds
[i
].codes
[0];
376 if (! strcmp ("const_int_operand", new->tests
))
380 for (j
= 0; j
< NUM_RTX_CODE
&& preds
[i
].codes
[j
] != 0; j
++)
381 if (preds
[i
].codes
[j
] == CONST_INT
)
382 allows_const_int
= 1;
384 if (! allows_const_int
)
385 new->enforce_mode
= new->ignore_mode
= 1;
390 if (code
== MATCH_OPERATOR
|| code
== MATCH_PARALLEL
)
392 for (i
= 0; i
< XVECLEN (pattern
, 2); i
++)
394 newpos
[depth
] = i
+ (code
== MATCH_OPERATOR
? '0': 'a');
395 new = add_to_sequence (XVECEXP (pattern
, 2, i
),
396 &new->success
, newpos
);
399 this->success
.first
->enforce_mode
= 0;
405 new->opno
= XINT (pattern
, 0);
406 new->dupno
= XINT (pattern
, 0);
409 for (i
= 0; i
< XVECLEN (pattern
, 1); i
++)
411 newpos
[depth
] = i
+ '0';
412 new = add_to_sequence (XVECEXP (pattern
, 1, i
),
413 &new->success
, newpos
);
415 this->success
.first
->enforce_mode
= 0;
419 new->dupno
= XINT (pattern
, 0);
421 new->enforce_mode
= 0;
425 pattern
= XEXP (pattern
, 0);
430 new = add_to_sequence (SET_DEST (pattern
), &new->success
, newpos
);
431 this->success
.first
->enforce_mode
= 1;
433 new = add_to_sequence (SET_SRC (pattern
), &new->success
, newpos
);
435 /* If set are setting CC0 from anything other than a COMPARE, we
436 must enforce the mode so that we do not produce ambiguous insns. */
437 if (GET_CODE (SET_DEST (pattern
)) == CC0
438 && GET_CODE (SET_SRC (pattern
)) != COMPARE
)
439 this->success
.first
->enforce_mode
= 1;
444 case STRICT_LOW_PART
:
446 new = add_to_sequence (XEXP (pattern
, 0), &new->success
, newpos
);
447 this->success
.first
->enforce_mode
= 1;
451 this->test_elt_one_int
= 1;
452 this->elt_one_int
= XINT (pattern
, 1);
454 new = add_to_sequence (XEXP (pattern
, 0), &new->success
, newpos
);
455 this->success
.first
->enforce_mode
= 1;
461 new = add_to_sequence (XEXP (pattern
, 0), &new->success
, newpos
);
462 this->success
.first
->enforce_mode
= 1;
464 new = add_to_sequence (XEXP (pattern
, 1), &new->success
, newpos
);
466 new = add_to_sequence (XEXP (pattern
, 2), &new->success
, newpos
);
469 case EQ
: case NE
: case LE
: case LT
: case GE
: case GT
:
470 case LEU
: case LTU
: case GEU
: case GTU
:
471 /* If the first operand is (cc0), we don't have to do anything
473 if (GET_CODE (XEXP (pattern
, 0)) == CC0
)
476 /* ... fall through ... */
479 /* Enforce the mode on the first operand to avoid ambiguous insns. */
481 new = add_to_sequence (XEXP (pattern
, 0), &new->success
, newpos
);
482 this->success
.first
->enforce_mode
= 1;
484 new = add_to_sequence (XEXP (pattern
, 1), &new->success
, newpos
);
488 fmt
= GET_RTX_FORMAT (code
);
489 len
= GET_RTX_LENGTH (code
);
490 for (i
= 0; i
< len
; i
++)
492 newpos
[depth
] = '0' + i
;
493 if (fmt
[i
] == 'e' || fmt
[i
] == 'u')
494 new = add_to_sequence (XEXP (pattern
, i
), &new->success
, newpos
);
495 else if (fmt
[i
] == 'i' && i
== 0)
497 this->test_elt_zero_int
= 1;
498 this->elt_zero_int
= XINT (pattern
, i
);
500 else if (fmt
[i
] == 'i' && i
== 1)
502 this->test_elt_one_int
= 1;
503 this->elt_one_int
= XINT (pattern
, i
);
505 else if (fmt
[i
] == 'E')
508 /* We do not handle a vector appearing as other than
509 the first item, just because nothing uses them
510 and by handling only the special case
511 we can use one element in newpos for either
512 the item number of a subexpression
513 or the element number in a vector. */
516 this->veclen
= XVECLEN (pattern
, i
);
517 for (j
= 0; j
< XVECLEN (pattern
, i
); j
++)
519 newpos
[depth
] = 'a' + j
;
520 new = add_to_sequence (XVECEXP (pattern
, i
, j
),
521 &new->success
, newpos
);
524 else if (fmt
[i
] != '0')
530 /* Return 1 if we can prove that there is no RTL that can match both
531 D1 and D2. Otherwise, return 0 (it may be that there is an RTL that
532 can match both or just that we couldn't prove there wasn't such an RTL).
534 TOPLEVEL is non-zero if we are to only look at the top level and not
535 recursively descend. */
538 not_both_true (d1
, d2
, toplevel
)
539 struct decision
*d1
, *d2
;
542 struct decision
*p1
, *p2
;
544 /* If they are both to test modes and the modes are different, they aren't
545 both true. Similarly for codes, integer elements, and vector lengths. */
547 if ((d1
->enforce_mode
&& d2
->enforce_mode
548 && d1
->mode
!= VOIDmode
&& d2
->mode
!= VOIDmode
&& d1
->mode
!= d2
->mode
)
549 || (d1
->code
!= UNKNOWN
&& d2
->code
!= UNKNOWN
&& d1
->code
!= d2
->code
)
550 || (d1
->test_elt_zero_int
&& d2
->test_elt_zero_int
551 && d1
->elt_zero_int
!= d2
->elt_zero_int
)
552 || (d1
->test_elt_one_int
&& d2
->test_elt_one_int
553 && d1
->elt_one_int
!= d2
->elt_one_int
)
554 || (d1
->veclen
&& d2
->veclen
&& d1
->veclen
!= d2
->veclen
))
557 /* If either is a wild-card MATCH_OPERAND without a predicate, it can match
558 absolutely anything, so we can't say that no intersection is possible.
559 This case is detected by having a zero TESTS field with a code of
562 if ((d1
->tests
== 0 && d1
->code
== UNKNOWN
)
563 || (d2
->tests
== 0 && d2
->code
== UNKNOWN
))
566 /* If either has a predicate that we know something about, set things up so
567 that D1 is the one that always has a known predicate. Then see if they
568 have any codes in common. */
570 if (d1
->pred
>= 0 || d2
->pred
>= 0)
575 p1
= d1
, d1
= d2
, d2
= p1
;
577 /* If D2 tests an explicit code, see if it is in the list of valid codes
578 for D1's predicate. */
579 if (d2
->code
!= UNKNOWN
)
581 for (i
= 0; i
< NUM_RTX_CODE
&& preds
[d1
->pred
].codes
[i
]; i
++)
582 if (preds
[d1
->pred
].codes
[i
] == d2
->code
)
585 if (preds
[d1
->pred
].codes
[i
] == 0)
589 /* Otherwise see if the predicates have any codes in common. */
591 else if (d2
->pred
>= 0)
593 for (i
= 0; i
< NUM_RTX_CODE
&& preds
[d1
->pred
].codes
[i
]; i
++)
595 for (j
= 0; j
< NUM_RTX_CODE
; j
++)
596 if (preds
[d2
->pred
].codes
[j
] == 0
597 || preds
[d2
->pred
].codes
[j
] == preds
[d1
->pred
].codes
[i
])
600 if (preds
[d2
->pred
].codes
[j
] != 0)
604 if (preds
[d1
->pred
].codes
[i
] == 0)
609 /* If we got here, we can't prove that D1 and D2 cannot both be true.
610 If we are only to check the top level, return 0. Otherwise, see if
611 we can prove that all choices in both successors are mutually
612 exclusive. If either does not have any successors, we can't prove
613 they can't both be true. */
615 if (toplevel
|| d1
->success
.first
== 0 || d2
->success
.first
== 0)
618 for (p1
= d1
->success
.first
; p1
; p1
= p1
->next
)
619 for (p2
= d2
->success
.first
; p2
; p2
= p2
->next
)
620 if (! not_both_true (p1
, p2
, 0))
626 /* Assuming that we can reorder all the alternatives at a specific point in
627 the tree (see discussion in merge_trees), we would prefer an ordering of
628 nodes where groups of consecutive nodes test the same mode and, within each
629 mode, groups of nodes test the same code. With this order, we can
630 construct nested switch statements, the inner one to test the code and
631 the outer one to test the mode.
633 We would like to list nodes testing for specific codes before those
634 that test predicates to avoid unnecessary function calls. Similarly,
635 tests for specific modes should preceed nodes that allow any mode.
637 This function returns the merit (with 0 being the best) of inserting
638 a test involving the specified MODE and CODE after node P. If P is
639 zero, we are to determine the merit of inserting the test at the front
643 position_merit (p
, mode
, code
)
645 enum machine_mode mode
;
648 enum machine_mode p_mode
;
650 /* The only time the front of the list is anything other than the worst
651 position is if we are testing a mode that isn't VOIDmode. */
653 return mode
== VOIDmode
? 3 : 2;
655 p_mode
= p
->enforce_mode
? p
->mode
: VOIDmode
;
657 /* The best case is if the codes and modes both match. */
658 if (p_mode
== mode
&& p
->code
== code
)
661 /* If the codes don't match, the next best case is if the modes match.
662 In that case, the best position for this node depends on whether
663 we are testing for a specific code or not. If we are, the best place
664 is after some other test for an explicit code and our mode or after
665 the last test in the previous mode if every test in our mode is for
668 If we are testing for UNKNOWN, then the next best case is at the end of
672 && ((p_mode
== mode
&& p
->code
!= UNKNOWN
)
673 || (p_mode
!= mode
&& p
->next
674 && (p
->next
->enforce_mode
? p
->next
->mode
: VOIDmode
) == mode
675 && (p
->next
->code
== UNKNOWN
))))
676 || (code
== UNKNOWN
&& p_mode
== mode
678 || (p
->next
->enforce_mode
? p
->next
->mode
: VOIDmode
) != mode
)))
681 /* The third best case occurs when nothing is testing MODE. If MODE
682 is not VOIDmode, then the third best case is after something of any
683 mode that is not VOIDmode. If we are testing VOIDmode, the third best
684 place is the end of the list. */
687 && ((mode
!= VOIDmode
&& p_mode
!= VOIDmode
)
688 || (mode
== VOIDmode
&& p
->next
== 0)))
691 /* Otherwise, we have the worst case. */
695 /* Merge two decision tree listheads OLDH and ADDH,
696 modifying OLDH destructively, and return the merged tree. */
698 static struct decision_head
699 merge_trees (oldh
, addh
)
700 register struct decision_head oldh
, addh
;
702 struct decision
*add
, *next
;
710 /* If we are adding things at different positions, something is wrong. */
711 if (strcmp (oldh
.first
->position
, addh
.first
->position
))
714 for (add
= addh
.first
; add
; add
= next
)
716 enum machine_mode add_mode
= add
->enforce_mode
? add
->mode
: VOIDmode
;
717 struct decision
*best_position
= 0;
719 struct decision
*old
;
723 /* The semantics of pattern matching state that the tests are done in
724 the order given in the MD file so that if an insn matches two
725 patterns, the first one will be used. However, in practice, most,
726 if not all, patterns are unambiguous so that their order is
727 independent. In that case, we can merge identical tests and
728 group all similar modes and codes together.
730 Scan starting from the end of OLDH until we reach a point
731 where we reach the head of the list or where we pass a pattern
732 that could also be true if NEW is true. If we find an identical
733 pattern, we can merge them. Also, record the last node that tests
734 the same code and mode and the last one that tests just the same mode.
736 If we have no match, place NEW after the closest match we found. */
738 for (old
= oldh
.last
; old
; old
= old
->prev
)
742 /* If we don't have anything to test except an additional test,
743 do not consider the two nodes equal. If we did, the test below
744 would cause an infinite recursion. */
745 if (old
->tests
== 0 && old
->test_elt_zero_int
== 0
746 && old
->test_elt_one_int
== 0 && old
->veclen
== 0
747 && old
->dupno
== -1 && old
->mode
== VOIDmode
748 && old
->code
== UNKNOWN
749 && (old
->c_test
!= 0 || add
->c_test
!= 0))
752 else if ((old
->tests
== add
->tests
753 || (old
->pred
>= 0 && old
->pred
== add
->pred
)
754 || (old
->tests
&& add
->tests
755 && !strcmp (old
->tests
, add
->tests
)))
756 && old
->test_elt_zero_int
== add
->test_elt_zero_int
757 && old
->elt_zero_int
== add
->elt_zero_int
758 && old
->test_elt_one_int
== add
->test_elt_one_int
759 && old
->elt_one_int
== add
->elt_one_int
760 && old
->veclen
== add
->veclen
761 && old
->dupno
== add
->dupno
762 && old
->opno
== add
->opno
763 && old
->code
== add
->code
764 && old
->enforce_mode
== add
->enforce_mode
765 && old
->mode
== add
->mode
)
767 /* If the additional test is not the same, split both nodes
768 into nodes that just contain all things tested before the
769 additional test and nodes that contain the additional test
770 and actions when it is true. This optimization is important
771 because of the case where we have almost identical patterns
772 with different tests on target flags. */
774 if (old
->c_test
!= add
->c_test
775 && ! (old
->c_test
&& add
->c_test
776 && !strcmp (old
->c_test
, add
->c_test
)))
778 if (old
->insn_code_number
>= 0 || old
->opno
>= 0)
780 struct decision
*split
781 = (struct decision
*) xmalloc (sizeof (struct decision
));
783 mybcopy (old
, split
, sizeof (struct decision
));
785 old
->success
.first
= old
->success
.last
= split
;
788 old
->insn_code_number
= -1;
789 old
->num_clobbers_to_add
= 0;
791 split
->number
= next_number
++;
792 split
->next
= split
->prev
= 0;
793 split
->mode
= VOIDmode
;
794 split
->code
= UNKNOWN
;
796 split
->test_elt_zero_int
= 0;
797 split
->test_elt_one_int
= 0;
802 if (add
->insn_code_number
>= 0 || add
->opno
>= 0)
804 struct decision
*split
805 = (struct decision
*) xmalloc (sizeof (struct decision
));
807 mybcopy (add
, split
, sizeof (struct decision
));
809 add
->success
.first
= add
->success
.last
= split
;
812 add
->insn_code_number
= -1;
813 add
->num_clobbers_to_add
= 0;
815 split
->number
= next_number
++;
816 split
->next
= split
->prev
= 0;
817 split
->mode
= VOIDmode
;
818 split
->code
= UNKNOWN
;
820 split
->test_elt_zero_int
= 0;
821 split
->test_elt_one_int
= 0;
827 old
->success
= merge_trees (old
->success
, add
->success
);
828 if (old
->insn_code_number
>= 0 && add
->insn_code_number
>= 0)
829 fatal ("Two actions at one point in tree");
830 if (old
->insn_code_number
== -1)
831 old
->insn_code_number
= add
->insn_code_number
;
836 /* Unless we have already found the best possible insert point,
837 see if this position is better. If so, record it. */
840 && ((our_merit
= position_merit (old
, add_mode
, add
->code
))
842 best_merit
= our_merit
, best_position
= old
;
844 if (! not_both_true (old
, add
, 0))
848 /* If ADD was duplicate, we are done. */
852 /* Otherwise, find the best place to insert ADD. Normally this is
853 BEST_POSITION. However, if we went all the way to the top of
854 the list, it might be better to insert at the top. */
856 if (best_position
== 0)
859 if (old
== 0 && position_merit (0, add_mode
, add
->code
) < best_merit
)
862 add
->next
= oldh
.first
;
863 oldh
.first
->prev
= add
;
869 add
->prev
= best_position
;
870 add
->next
= best_position
->next
;
871 best_position
->next
= add
;
872 if (best_position
== oldh
.last
)
875 add
->next
->prev
= add
;
882 /* Count the number of subnodes of HEAD. If the number is high enough,
883 make the first node in HEAD start a separate subroutine in the C code
886 TYPE gives the type of routine we are writing.
888 INITIAL is non-zero if this is the highest-level node. We never write
892 break_out_subroutines (head
, type
, initial
)
893 struct decision_head head
;
894 enum routine_type type
;
898 struct decision
*node
, *sub
;
900 for (sub
= head
.first
; sub
; sub
= sub
->next
)
901 size
+= 1 + break_out_subroutines (sub
->success
, type
, 0);
903 if (size
> SUBROUTINE_THRESHOLD
&& ! initial
)
905 head
.first
->subroutine_number
= ++next_subroutine_number
;
906 write_subroutine (head
.first
, type
);
912 /* Write out a subroutine of type TYPE to do comparisons starting at node
916 write_subroutine (tree
, type
)
917 struct decision
*tree
;
918 enum routine_type type
;
923 printf ("rtx\nsplit");
925 printf ("int\nrecog");
927 if (tree
!= 0 && tree
->subroutine_number
> 0)
928 printf ("_%d", tree
->subroutine_number
);
929 else if (type
== SPLIT
)
932 printf (" (x0, insn");
934 printf (", pnum_clobbers");
937 printf (" register rtx x0;\n rtx insn;\n");
939 printf (" int *pnum_clobbers;\n");
942 printf (" register rtx *ro = &recog_operand[0];\n");
944 printf (" register rtx ");
945 for (i
= 1; i
< max_depth
; i
++)
948 printf ("x%d;\n", max_depth
);
949 printf (" %s tem;\n", type
== SPLIT
? "rtx" : "int");
950 write_tree (tree
, "", 0, 1, type
);
951 printf (" ret0: return %d;\n}\n\n", type
== SPLIT
? 0 : -1);
954 /* This table is used to indent the recog_* functions when we are inside
955 conditions or switch statements. We only support small indentations
956 and always indent at least two spaces. */
958 static char *indents
[]
959 = {" ", " ", " ", " ", " ", " ", " ", " ",
960 "\t", "\t ", "\t ", "\t ", "\t ", "\t ", "\t ",
961 "\t\t", "\t\t ", "\t\t ", "\t\t ", "\t\t ", "\t\t "};
963 /* Write out C code to perform the decisions in TREE for a subroutine of
964 type TYPE. If all of the choices fail, branch to node AFTERWARD, if
965 non-zero, otherwise return. PREVPOS is the position of the node that
966 branched to this test.
968 When we merged all alternatives, we tried to set up a convenient order.
969 Specifically, tests involving the same mode are all grouped together,
970 followed by a group that does not contain a mode test. Within each group
971 of the same mode, we also group tests with the same code, followed by a
972 group that does not test a code.
974 Occasionally, we cannot arbitarily reorder the tests so that multiple
975 sequence of groups as described above are present.
977 We generate two nested switch statements, the outer statement for
978 testing modes, and the inner switch for testing RTX codes. It is
979 not worth optimizing cases when only a small number of modes or
980 codes is tested, since the compiler can do that when compiling the
981 resulting function. We do check for when every test is the same mode
985 write_tree_1 (tree
, prevpos
, afterward
, type
)
986 struct decision
*tree
;
988 struct decision
*afterward
;
989 enum routine_type type
;
991 register struct decision
*p
, *p1
;
992 register int depth
= tree
? strlen (tree
->position
) : 0;
993 enum machine_mode switch_mode
= VOIDmode
;
994 RTX_CODE switch_code
= UNKNOWN
;
996 char modemap
[NUM_MACHINE_MODES
];
997 char codemap
[NUM_RTX_CODE
];
1001 /* One tricky area is what is the exact state when we branch to a
1002 node's label. There are two cases where we branch: when looking at
1003 successors to a node, or when a set of tests fails.
1005 In the former case, we are always branching to the first node in a
1006 decision list and we want all required tests to be performed. We
1007 put the labels for such nodes in front of any switch or test statements.
1008 These branches are done without updating the position to that of the
1011 In the latter case, we are branching to a node that is not the first
1012 node in a decision list. We have already checked that it is possible
1013 for both the node we originally tested at this level and the node we
1014 are branching to to be both match some pattern. That means that they
1015 usually will be testing the same mode and code. So it is normally safe
1016 for such labels to be inside switch statements, since the tests done
1017 by virtue of arriving at that label will usually already have been
1018 done. The exception is a branch from a node that does not test a
1019 mode or code to one that does. In such cases, we set the `retest_mode'
1020 or `retest_code' flags. That will ensure that we start a new switch
1021 at that position and put the label before the switch.
1023 The branches in the latter case must set the position to that of the
1028 if (tree
&& tree
->subroutine_number
== 0)
1030 printf (" L%d:\n", tree
->number
);
1031 tree
->label_needed
= 0;
1036 change_state (prevpos
, tree
->position
, 2);
1037 prevpos
= tree
->position
;
1040 for (p
= tree
; p
; p
= p
->next
)
1042 enum machine_mode mode
= p
->enforce_mode
? p
->mode
: VOIDmode
;
1045 if (p
->success
.first
== 0 && p
->insn_code_number
< 0)
1048 /* Find the next alternative to p that might be true when p is true.
1049 Test that one next if p's successors fail. */
1051 for (p1
= p
->next
; p1
&& not_both_true (p
, p1
, 1); p1
= p1
->next
)
1057 if (mode
== VOIDmode
&& p1
->enforce_mode
&& p1
->mode
!= VOIDmode
)
1058 p1
->retest_mode
= 1;
1059 if (p
->code
== UNKNOWN
&& p1
->code
!= UNKNOWN
)
1060 p1
->retest_code
= 1;
1061 p1
->label_needed
= 1;
1064 /* If we have a different code or mode than the last node and
1065 are in a switch on codes, we must either end the switch or
1066 go to another case. We must also end the switch if this
1067 node needs a label and to retest either the mode or code. */
1069 if (switch_code
!= UNKNOWN
1070 && (switch_code
!= p
->code
|| switch_mode
!= mode
1071 || (p
->label_needed
&& (p
->retest_mode
|| p
->retest_code
))))
1073 enum rtx_code code
= p
->code
;
1075 /* If P is testing a predicate that we know about and we haven't
1076 seen any of the codes that are valid for the predicate, we
1077 can write a series of "case" statement, one for each possible
1078 code. Since we are already in a switch, these redundant tests
1079 are very cheap and will reduce the number of predicate called. */
1083 for (i
= 0; i
< NUM_RTX_CODE
&& preds
[p
->pred
].codes
[i
]; i
++)
1084 if (codemap
[(int) preds
[p
->pred
].codes
[i
]])
1087 if (preds
[p
->pred
].codes
[i
] == 0)
1088 code
= MATCH_OPERAND
;
1091 if (code
== UNKNOWN
|| codemap
[(int) code
]
1092 || switch_mode
!= mode
1093 || (p
->label_needed
&& (p
->retest_mode
|| p
->retest_code
)))
1095 printf ("%s}\n", indents
[indent
- 2]);
1096 switch_code
= UNKNOWN
;
1102 printf ("%sbreak;\n", indents
[indent
]);
1104 if (code
== MATCH_OPERAND
)
1106 for (i
= 0; i
< NUM_RTX_CODE
&& preds
[p
->pred
].codes
[i
]; i
++)
1108 printf ("%scase ", indents
[indent
- 2]);
1109 print_code (preds
[p
->pred
].codes
[i
]);
1111 codemap
[(int) preds
[p
->pred
].codes
[i
]] = 1;
1116 printf ("%scase ", indents
[indent
- 2]);
1119 codemap
[(int) p
->code
] = 1;
1128 /* If we were previously in a switch on modes and now have a different
1129 mode, end at least the case, and maybe end the switch if we are
1130 not testing a mode or testing a mode whose case we already saw. */
1132 if (switch_mode
!= VOIDmode
1133 && (switch_mode
!= mode
|| (p
->label_needed
&& p
->retest_mode
)))
1135 if (mode
== VOIDmode
|| modemap
[(int) mode
]
1136 || (p
->label_needed
&& p
->retest_mode
))
1138 printf ("%s}\n", indents
[indent
- 2]);
1139 switch_mode
= VOIDmode
;
1145 printf (" break;\n");
1146 printf (" case %smode:\n", GET_MODE_NAME (mode
));
1148 modemap
[(int) mode
] = 1;
1154 /* If we are about to write dead code, something went wrong. */
1155 if (! p
->label_needed
&& uncond
)
1158 /* If we need a label and we will want to retest the mode or code at
1159 that label, write the label now. We have already ensured that
1160 things will be valid for the test. */
1162 if (p
->label_needed
&& (p
->retest_mode
|| p
->retest_code
))
1164 printf ("%sL%d:\n", indents
[indent
- 2], p
->number
);
1165 p
->label_needed
= 0;
1170 /* If we are not in any switches, see if we can shortcut things
1171 by checking for identical modes and codes. */
1173 if (switch_mode
== VOIDmode
&& switch_code
== UNKNOWN
)
1175 /* If p and its alternatives all want the same mode,
1176 reject all others at once, first, then ignore the mode. */
1178 if (mode
!= VOIDmode
&& p
->next
&& same_modes (p
, mode
))
1180 printf (" if (GET_MODE (x%d) != %smode)\n",
1181 depth
, GET_MODE_NAME (p
->mode
));
1185 change_state (p
->position
, afterward
->position
, 6);
1186 printf (" goto L%d;\n }\n", afterward
->number
);
1189 printf (" goto ret0;\n");
1194 /* If p and its alternatives all want the same code,
1195 reject all others at once, first, then ignore the code. */
1197 if (p
->code
!= UNKNOWN
&& p
->next
&& same_codes (p
, p
->code
))
1199 printf (" if (GET_CODE (x%d) != ", depth
);
1200 print_code (p
->code
);
1205 change_state (p
->position
, afterward
->position
, indent
+ 4);
1206 printf (" goto L%d;\n }\n", afterward
->number
);
1209 printf (" goto ret0;\n");
1214 /* If we are not in a mode switch and we are testing for a specific
1215 mode, start a mode switch unless we have just one node or the next
1216 node is not testing a mode (we have already tested for the case of
1217 more than one mode, but all of the same mode). */
1219 if (switch_mode
== VOIDmode
&& mode
!= VOIDmode
&& p
->next
!= 0
1220 && p
->next
->enforce_mode
&& p
->next
->mode
!= VOIDmode
)
1222 mybzero (modemap
, sizeof modemap
);
1223 printf ("%sswitch (GET_MODE (x%d))\n", indents
[indent
], depth
);
1224 printf ("%s{\n", indents
[indent
+ 2]);
1226 printf ("%scase %smode:\n", indents
[indent
- 2],
1227 GET_MODE_NAME (mode
));
1228 modemap
[(int) mode
] = 1;
1232 /* Similarly for testing codes. */
1234 if (switch_code
== UNKNOWN
&& p
->code
!= UNKNOWN
&& ! p
->ignore_code
1235 && p
->next
!= 0 && p
->next
->code
!= UNKNOWN
)
1237 mybzero (codemap
, sizeof codemap
);
1238 printf ("%sswitch (GET_CODE (x%d))\n", indents
[indent
], depth
);
1239 printf ("%s{\n", indents
[indent
+ 2]);
1241 printf ("%scase ", indents
[indent
- 2]);
1242 print_code (p
->code
);
1244 codemap
[(int) p
->code
] = 1;
1245 switch_code
= p
->code
;
1248 /* Now that most mode and code tests have been done, we can write out
1249 a label for an inner node, if we haven't already. */
1250 if (p
->label_needed
)
1251 printf ("%sL%d:\n", indents
[indent
- 2], p
->number
);
1253 inner_indent
= indent
;
1255 /* The only way we can have to do a mode or code test here is if
1256 this node needs such a test but is the only node to be tested.
1257 In that case, we won't have started a switch. Note that this is
1258 the only way the switch and test modes can disagree. */
1260 if ((mode
!= switch_mode
&& ! p
->ignore_mode
)
1261 || (p
->code
!= switch_code
&& p
->code
!= UNKNOWN
&& ! p
->ignore_code
)
1262 || p
->test_elt_zero_int
|| p
->test_elt_one_int
|| p
->veclen
1263 || p
->dupno
>= 0 || p
->tests
|| p
->num_clobbers_to_add
)
1265 printf ("%sif (", indents
[indent
]);
1267 if (mode
!= switch_mode
&& ! p
->ignore_mode
)
1268 printf ("GET_MODE (x%d) == %smode && ",
1269 depth
, GET_MODE_NAME (mode
));
1270 if (p
->code
!= switch_code
&& p
->code
!= UNKNOWN
&& ! p
->ignore_code
)
1272 printf ("GET_CODE (x%d) == ", depth
);
1273 print_code (p
->code
);
1277 if (p
->test_elt_zero_int
)
1278 printf ("XINT (x%d, 0) == %d && ", depth
, p
->elt_zero_int
);
1279 if (p
->test_elt_one_int
)
1280 printf ("XINT (x%d, 1) == %d && ", depth
, p
->elt_one_int
);
1282 printf ("XVECLEN (x%d, 0) == %d && ", depth
, p
->veclen
);
1284 printf ("rtx_equal_p (x%d, ro[%d]) && ", depth
, p
->dupno
);
1285 if (p
->num_clobbers_to_add
)
1286 printf ("pnum_clobbers != 0 && ");
1288 printf ("%s (x%d, %smode)", p
->tests
, depth
,
1289 GET_MODE_NAME (p
->mode
));
1301 printf ("%s{\n%sro[%d] = x%d;\n",
1302 indents
[inner_indent
], indents
[inner_indent
+ 2],
1309 printf ("%sif (%s)\n", indents
[inner_indent
], p
->c_test
);
1314 if (p
->insn_code_number
>= 0)
1317 printf ("%sreturn gen_split_%d (operands);\n",
1318 indents
[inner_indent
], p
->insn_code_number
);
1321 if (p
->num_clobbers_to_add
)
1323 if (p
->opno
< 0 || p
->c_test
)
1325 printf ("%s{\n", indents
[inner_indent
]);
1329 printf ("%s*pnum_clobbers = %d;\n",
1330 indents
[inner_indent
], p
->num_clobbers_to_add
);
1331 printf ("%sreturn %d;\n",
1332 indents
[inner_indent
], p
->insn_code_number
);
1334 if (p
->opno
< 0 || p
->c_test
)
1337 printf ("%s}\n", indents
[inner_indent
]);
1341 printf ("%sreturn %d;\n",
1342 indents
[inner_indent
], p
->insn_code_number
);
1346 printf ("%sgoto L%d;\n", indents
[inner_indent
],
1347 p
->success
.first
->number
);
1350 printf ("%s}\n", indents
[inner_indent
- 2]);
1353 /* We have now tested all alternatives. End any switches we have open
1354 and branch to the alternative node. */
1356 if (switch_code
!= UNKNOWN
)
1358 printf ("%s}\n", indents
[indent
- 2]);
1362 if (switch_mode
!= VOIDmode
)
1364 printf ("%s}\n", indents
[indent
- 2]);
1373 change_state (prevpos
, afterward
->position
, 2);
1374 printf (" goto L%d;\n", afterward
->number
);
1377 printf (" goto ret0;\n");
1385 for (p1
= GET_RTX_NAME (code
); *p1
; p1
++)
1387 if (*p1
>= 'a' && *p1
<= 'z')
1388 putchar (*p1
+ 'A' - 'a');
1395 same_codes (p
, code
)
1396 register struct decision
*p
;
1397 register RTX_CODE code
;
1399 for (; p
; p
= p
->next
)
1400 if (p
->code
!= code
)
1408 register struct decision
*p
;
1410 for (; p
; p
= p
->next
)
1415 same_modes (p
, mode
)
1416 register struct decision
*p
;
1417 register enum machine_mode mode
;
1419 for (; p
; p
= p
->next
)
1420 if (p
->mode
!= mode
|| p
->tests
)
1428 register struct decision
*p
;
1430 for (; p
; p
= p
->next
)
1431 p
->enforce_mode
= 0;
1434 /* Write out the decision tree starting at TREE for a subroutine of type TYPE.
1436 PREVPOS is the position at the node that branched to this node.
1438 INITIAL is nonzero if this is the first node we are writing in a subroutine.
1440 If all nodes are false, branch to the node AFTERWARD. */
1443 write_tree (tree
, prevpos
, afterward
, initial
, type
)
1444 struct decision
*tree
;
1446 struct decision
*afterward
;
1448 enum routine_type type
;
1450 register struct decision
*p
;
1451 char *name_prefix
= (type
== SPLIT
? "split" : "recog");
1452 char *call_suffix
= (type
== SPLIT
? "" : ", pnum_clobbers");
1454 if (! initial
&& tree
->subroutine_number
> 0)
1456 printf (" L%d:\n", tree
->number
);
1460 printf (" tem = %s_%d (x0, insn%s);\n",
1461 name_prefix
, tree
->subroutine_number
, call_suffix
);
1462 printf (" if (tem >= 0) return tem;\n");
1463 change_state (tree
->position
, afterward
->position
, 2);
1464 printf (" goto L%d;\n", afterward
->number
);
1467 printf (" return %s_%d (x0, insn%s);\n",
1468 name_prefix
, tree
->subroutine_number
, call_suffix
);
1472 write_tree_1 (tree
, prevpos
, afterward
, type
);
1474 for (p
= tree
; p
; p
= p
->next
)
1475 if (p
->success
.first
)
1476 write_tree (p
->success
.first
, p
->position
,
1477 p
->afterward
? p
->afterward
: afterward
, 0, type
);
1481 /* Assuming that the state of argument is denoted by OLDPOS, take whatever
1482 actions are necessary to move to NEWPOS.
1484 INDENT says how many blanks to place at the front of lines. */
1487 change_state (oldpos
, newpos
, indent
)
1492 int odepth
= strlen (oldpos
);
1494 int ndepth
= strlen (newpos
);
1496 /* Pop up as many levels as necessary. */
1498 while (strncmp (oldpos
, newpos
, depth
))
1501 /* Go down to desired level. */
1503 while (depth
< ndepth
)
1505 if (newpos
[depth
] >= 'a' && newpos
[depth
] <= 'z')
1506 printf ("%sx%d = XVECEXP (x%d, 0, %d);\n",
1507 indents
[indent
], depth
+ 1, depth
, newpos
[depth
] - 'a');
1509 printf ("%sx%d = XEXP (x%d, %c);\n",
1510 indents
[indent
], depth
+ 1, depth
, newpos
[depth
]);
1524 tem
= (char *) xmalloc (strlen (s1
) + 1);
1533 register unsigned length
;
1535 while (length
-- > 0)
1540 mybcopy (in
, out
, length
)
1541 register char *in
, *out
;
1542 register unsigned length
;
1544 while (length
-- > 0)
1559 tem
= (char *) xmalloc (strlen (s1
) + strlen (s2
) + 2);
1568 xrealloc (ptr
, size
)
1572 char *result
= (char *) realloc (ptr
, size
);
1574 fatal ("virtual memory exhausted");
1582 register char *val
= (char *) malloc (size
);
1585 fatal ("virtual memory exhausted");
1593 fprintf (stderr
, "genrecog: ");
1594 fprintf (stderr
, s
, a1
, a2
);
1595 fprintf (stderr
, "\n");
1596 fprintf (stderr
, "after %d instruction definitions\n", next_index
);
1597 exit (FATAL_EXIT_CODE
);
1600 /* More 'friendly' abort that prints the line and file.
1601 config.h can #define abort fancy_abort if you like that sort of thing. */
1606 fatal ("Internal gcc abort.");
1615 struct decision_head recog_tree
;
1616 struct decision_head split_tree
;
1618 extern rtx
read_rtx ();
1621 obstack_init (rtl_obstack
);
1622 recog_tree
.first
= recog_tree
.last
= split_tree
.first
= split_tree
.last
= 0;
1625 fatal ("No input file name.");
1627 infile
= fopen (argv
[1], "r");
1631 exit (FATAL_EXIT_CODE
);
1638 printf ("/* Generated automatically by the program `genrecog'\n\
1639 from the machine description file `md'. */\n\n");
1641 printf ("#include \"config.h\"\n");
1642 printf ("#include \"rtl.h\"\n");
1643 printf ("#include \"insn-config.h\"\n");
1644 printf ("#include \"recog.h\"\n");
1645 printf ("#include \"real.h\"\n");
1646 printf ("#include \"output.h\"\n");
1647 printf ("#include \"flags.h\"\n");
1650 /* Read the machine description. */
1654 c
= read_skip_spaces (infile
);
1659 desc
= read_rtx (infile
);
1660 if (GET_CODE (desc
) == DEFINE_INSN
)
1661 recog_tree
= merge_trees (recog_tree
,
1662 make_insn_sequence (desc
, RECOG
));
1663 else if (GET_CODE (desc
) == DEFINE_SPLIT
)
1664 split_tree
= merge_trees (split_tree
,
1665 make_insn_sequence (desc
, SPLIT
));
1666 if (GET_CODE (desc
) == DEFINE_PEEPHOLE
1667 || GET_CODE (desc
) == DEFINE_EXPAND
)
1673 /* `recog' contains a decision tree\n\
1674 that recognizes whether the rtx X0 is a valid instruction.\n\
1676 recog returns -1 if the rtx is not valid.\n\
1677 If the rtx is valid, recog returns a nonnegative number\n\
1678 which is the insn code number for the pattern that matched.\n");
1679 printf (" This is the same as the order in the machine description of\n\
1680 the entry that matched. This number can be used as an index into\n\
1681 entry that matched. This number can be used as an index into various\n\
1682 insn_* tables, such as insn_templates, insn_outfun, and insn_n_operands\n\
1683 (found in insn-output.c).\n\n");
1684 printf (" The third argument to recog is an optional pointer to an int.\n\
1685 If present, recog will accept a pattern if it matches except for\n\
1686 missing CLOBBER expressions at the end. In that case, the value\n\
1687 pointed to by the optional pointer will be set to the number of\n\
1688 CLOBBERs that need to be added (it should be initialized to zero by\n\
1689 the caller). If it is set nonzero, the caller should allocate a\n\
1690 PARALLEL of the appropriate size, copy the initial entries, and call\n\
1691 add_clobbers (found in insn-emit.c) to fill in the CLOBBERs.");
1693 if (split_tree
.first
)
1694 printf ("\n\n The function split_insns returns 0 if the rtl could not\n\
1695 be split or the split rtl in a SEQUENCE if it can be.");
1699 printf ("rtx recog_operand[MAX_RECOG_OPERANDS];\n\n");
1700 printf ("rtx *recog_operand_loc[MAX_RECOG_OPERANDS];\n\n");
1701 printf ("rtx *recog_dup_loc[MAX_DUP_OPERANDS];\n\n");
1702 printf ("char recog_dup_num[MAX_DUP_OPERANDS];\n\n");
1703 printf ("#define operands recog_operand\n\n");
1705 next_subroutine_number
= 0;
1706 break_out_subroutines (recog_tree
, RECOG
, 1);
1707 write_subroutine (recog_tree
.first
, RECOG
);
1709 next_subroutine_number
= 0;
1710 break_out_subroutines (split_tree
, SPLIT
, 1);
1711 write_subroutine (split_tree
.first
, SPLIT
);
1714 exit (ferror (stdout
) != 0 ? FATAL_EXIT_CODE
: SUCCESS_EXIT_CODE
);