1 /* Generate code from machine description to recognize rtl as insns.
2 Copyright (C) 1987, 1988, 1992 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
60 extern rtx
read_rtx ();
62 /* Data structure for a listhead of decision trees. The alternatives
63 to a node are kept in a doublely-linked list so we can easily add nodes
64 to the proper place when merging. */
66 struct decision_head
{ struct decision
*first
, *last
; };
68 /* Data structure for decision tree for recognizing
69 legitimate instructions. */
73 int number
; /* Node number, used for labels */
74 char *position
; /* String denoting position in pattern */
75 RTX_CODE code
; /* Code to test for or UNKNOWN to suppress */
76 char ignore_code
; /* If non-zero, need not test code */
77 char ignore_mode
; /* If non-zero, need not test mode */
78 int veclen
; /* Length of vector, if nonzero */
79 enum machine_mode mode
; /* Machine mode of node */
80 char enforce_mode
; /* If non-zero, test `mode' */
81 char retest_code
, retest_mode
; /* See write_tree_1 */
82 int test_elt_zero_int
; /* Nonzero if should test XINT (rtl, 0) */
83 int elt_zero_int
; /* Required value for XINT (rtl, 0) */
84 int test_elt_one_int
; /* Nonzero if should test XINT (rtl, 1) */
85 int elt_one_int
; /* Required value for XINT (rtl, 1) */
86 char *tests
; /* If nonzero predicate to call */
87 int pred
; /* `preds' index of predicate or -1 */
88 char *c_test
; /* Additional test to perform */
89 struct decision_head success
; /* Nodes to test on success */
90 int insn_code_number
; /* Insn number matched, if success */
91 int num_clobbers_to_add
; /* Number of CLOBBERs to be added to pattern */
92 struct decision
*next
; /* Node to test on failure */
93 struct decision
*prev
; /* Node whose failure tests us */
94 struct decision
*afterward
; /* Node to test on success, but failure of
96 int opno
; /* Operand number, if >= 0 */
97 int dupno
; /* Number of operand to compare against */
98 int label_needed
; /* Nonzero if label needed when writing tree */
99 int subroutine_number
; /* Number of subroutine this node starts */
102 #define SUBROUTINE_THRESHOLD 50
104 static int next_subroutine_number
;
106 /* We can write two types of subroutines: One for insn recognition and
107 one to split insns. This defines which type is being written. */
109 enum routine_type
{RECOG
, SPLIT
};
111 /* Next available node number for tree nodes. */
113 static int next_number
;
115 /* Next number to use as an insn_code. */
117 static int next_insn_code
;
119 /* Similar, but counts all expressions in the MD file; used for
122 static int next_index
;
124 /* Record the highest depth we ever have so we know how many variables to
125 allocate in each subroutine we make. */
127 static int max_depth
;
129 /* This table contains a list of the rtl codes that can possibly match a
130 predicate defined in recog.c. The function `not_both_true' uses it to
131 deduce that there are no expressions that can be matches by certain pairs
132 of tree nodes. Also, if a predicate can match only one code, we can
133 hardwire that code into the node testing the predicate. */
135 static struct pred_table
138 RTX_CODE codes
[NUM_RTX_CODE
];
140 = {{"general_operand", {CONST_INT
, CONST_DOUBLE
, CONST
, SYMBOL_REF
,
141 LABEL_REF
, SUBREG
, REG
, MEM
}},
142 #ifdef PREDICATE_CODES
145 {"address_operand", {CONST_INT
, CONST_DOUBLE
, CONST
, SYMBOL_REF
,
146 LABEL_REF
, SUBREG
, REG
, MEM
, PLUS
, MINUS
, MULT
}},
147 {"register_operand", {SUBREG
, REG
}},
148 {"scratch_operand", {SCRATCH
, REG
}},
149 {"immediate_operand", {CONST_INT
, CONST_DOUBLE
, CONST
, SYMBOL_REF
,
151 {"const_int_operand", {CONST_INT
}},
152 {"const_double_operand", {CONST_INT
, CONST_DOUBLE
}},
153 {"nonimmediate_operand", {SUBREG
, REG
, MEM
}},
154 {"nonmemory_operand", {CONST_INT
, CONST_DOUBLE
, CONST
, SYMBOL_REF
,
155 LABEL_REF
, SUBREG
, REG
}},
156 {"push_operand", {MEM
}},
157 {"memory_operand", {SUBREG
, MEM
}},
158 {"indirect_operand", {SUBREG
, MEM
}},
159 {"comparison_operation", {EQ
, NE
, LE
, LT
, GE
, LT
, LEU
, LTU
, GEU
, GTU
}},
160 {"mode_independent_operand", {CONST_INT
, CONST_DOUBLE
, CONST
, SYMBOL_REF
,
161 LABEL_REF
, SUBREG
, REG
, MEM
}}};
163 #define NUM_KNOWN_PREDS (sizeof preds / sizeof preds[0])
165 static int try_merge_1 ();
166 static int no_same_mode ();
167 static int same_codes ();
168 static int same_modes ();
170 static struct decision
*add_to_sequence ();
171 static struct decision_head
merge_trees ();
172 static struct decision
*try_merge_2 ();
173 static void write_subroutine ();
174 static void print_code ();
175 static void clear_codes ();
176 static void clear_modes ();
177 static void change_state ();
178 static void write_tree ();
179 static char *copystr ();
180 static char *concat ();
181 static void fatal ();
183 static void mybzero ();
184 static void mybcopy ();
186 /* Construct and return a sequence of decisions
187 that will recognize INSN.
189 TYPE says what type of routine we are recognizing (RECOG or SPLIT). */
191 static struct decision_head
192 make_insn_sequence (insn
, type
)
194 enum routine_type type
;
197 char *c_test
= XSTR (insn
, type
== RECOG
? 2 : 1);
198 struct decision
*last
;
199 struct decision_head head
;
201 if (XVECLEN (insn
, type
== RECOG
) == 1)
202 x
= XVECEXP (insn
, type
== RECOG
, 0);
205 x
= rtx_alloc (PARALLEL
);
206 XVEC (x
, 0) = XVEC (insn
, type
== RECOG
);
207 PUT_MODE (x
, VOIDmode
);
210 last
= add_to_sequence (x
, &head
, "");
213 last
->c_test
= c_test
;
214 last
->insn_code_number
= next_insn_code
;
215 last
->num_clobbers_to_add
= 0;
217 /* If this is not a DEFINE_SPLIT and X is a PARALLEL, see if it ends with a
218 group of CLOBBERs of (hard) registers or MATCH_SCRATCHes. If so, set up
219 to recognize the pattern without these CLOBBERs. */
221 if (type
== RECOG
&& GET_CODE (x
) == PARALLEL
)
225 for (i
= XVECLEN (x
, 0); i
> 0; i
--)
226 if (GET_CODE (XVECEXP (x
, 0, i
- 1)) != CLOBBER
227 || (GET_CODE (XEXP (XVECEXP (x
, 0, i
- 1), 0)) != REG
228 && GET_CODE (XEXP (XVECEXP (x
, 0, i
- 1), 0)) != MATCH_SCRATCH
))
231 if (i
!= XVECLEN (x
, 0))
234 struct decision_head clobber_head
;
237 new = XVECEXP (x
, 0, 0);
242 new = rtx_alloc (PARALLEL
);
243 XVEC (new, 0) = rtvec_alloc (i
);
244 for (j
= i
- 1; j
>= 0; j
--)
245 XVECEXP (new, 0, j
) = XVECEXP (x
, 0, j
);
248 last
= add_to_sequence (new, &clobber_head
, "");
251 last
->c_test
= c_test
;
252 last
->insn_code_number
= next_insn_code
;
253 last
->num_clobbers_to_add
= XVECLEN (x
, 0) - i
;
255 head
= merge_trees (head
, clobber_head
);
262 /* Define the subroutine we will call below and emit in genemit. */
263 printf ("extern rtx gen_split_%d ();\n", last
->insn_code_number
);
268 /* Create a chain of nodes to verify that an rtl expression matches
271 LAST is a pointer to the listhead in the previous node in the chain (or
272 in the calling function, for the first node).
274 POSITION is the string representing the current position in the insn.
276 A pointer to the final node in the chain is returned. */
278 static struct decision
*
279 add_to_sequence (pattern
, last
, position
)
281 struct decision_head
*last
;
284 register RTX_CODE code
;
285 register struct decision
*new
286 = (struct decision
*) xmalloc (sizeof (struct decision
));
287 struct decision
*this;
291 int depth
= strlen (position
);
294 if (depth
> max_depth
)
297 new->number
= next_number
++;
298 new->position
= copystr (position
);
299 new->ignore_code
= 0;
300 new->ignore_mode
= 0;
301 new->enforce_mode
= 1;
302 new->retest_code
= new->retest_mode
= 0;
304 new->test_elt_zero_int
= 0;
305 new->test_elt_one_int
= 0;
306 new->elt_zero_int
= 0;
307 new->elt_one_int
= 0;
311 new->success
.first
= new->success
.last
= 0;
312 new->insn_code_number
= -1;
313 new->num_clobbers_to_add
= 0;
319 new->label_needed
= 0;
320 new->subroutine_number
= 0;
324 last
->first
= last
->last
= new;
326 newpos
= (char *) alloca (depth
+ 2);
327 strcpy (newpos
, position
);
328 newpos
[depth
+ 1] = 0;
332 new->mode
= GET_MODE (pattern
);
333 new->code
= code
= GET_CODE (pattern
);
341 new->opno
= XINT (pattern
, 0);
342 new->code
= (code
== MATCH_PARALLEL
? PARALLEL
: UNKNOWN
);
343 new->enforce_mode
= 0;
345 if (code
== MATCH_SCRATCH
)
346 new->tests
= "scratch_operand";
348 new->tests
= XSTR (pattern
, 1);
350 if (*new->tests
== 0)
353 /* See if we know about this predicate and save its number. If we do,
354 and it only accepts one code, note that fact. The predicate
355 `const_int_operand' only tests for a CONST_INT, so if we do so we
356 can avoid calling it at all.
358 Finally, if we know that the predicate does not allow CONST_INT, we
359 know that the only way the predicate can match is if the modes match
360 (here we use the kluge of relying on the fact that "address_operand"
361 accepts CONST_INT; otherwise, it would have to be a special case),
362 so we can test the mode (but we need not). This fact should
363 considerably simplify the generated code. */
366 for (i
= 0; i
< NUM_KNOWN_PREDS
; i
++)
367 if (! strcmp (preds
[i
].name
, new->tests
))
370 int allows_const_int
= 0;
374 if (preds
[i
].codes
[1] == 0 && new->code
== UNKNOWN
)
376 new->code
= preds
[i
].codes
[0];
377 if (! strcmp ("const_int_operand", new->tests
))
378 new->tests
= 0, new->pred
= -1;
381 for (j
= 0; j
< NUM_RTX_CODE
&& preds
[i
].codes
[j
] != 0; j
++)
382 if (preds
[i
].codes
[j
] == CONST_INT
)
383 allows_const_int
= 1;
385 if (! allows_const_int
)
386 new->enforce_mode
= new->ignore_mode
= 1;
391 if (code
== MATCH_OPERATOR
|| code
== MATCH_PARALLEL
)
393 for (i
= 0; i
< XVECLEN (pattern
, 2); i
++)
395 newpos
[depth
] = i
+ (code
== MATCH_OPERATOR
? '0': 'a');
396 new = add_to_sequence (XVECEXP (pattern
, 2, i
),
397 &new->success
, newpos
);
400 this->success
.first
->enforce_mode
= 0;
406 new->opno
= XINT (pattern
, 0);
407 new->dupno
= XINT (pattern
, 0);
410 for (i
= 0; i
< XVECLEN (pattern
, 1); i
++)
412 newpos
[depth
] = i
+ '0';
413 new = add_to_sequence (XVECEXP (pattern
, 1, i
),
414 &new->success
, newpos
);
416 this->success
.first
->enforce_mode
= 0;
420 new->dupno
= XINT (pattern
, 0);
422 new->enforce_mode
= 0;
426 pattern
= XEXP (pattern
, 0);
431 new = add_to_sequence (SET_DEST (pattern
), &new->success
, newpos
);
432 this->success
.first
->enforce_mode
= 1;
434 new = add_to_sequence (SET_SRC (pattern
), &new->success
, newpos
);
436 /* If set are setting CC0 from anything other than a COMPARE, we
437 must enforce the mode so that we do not produce ambiguous insns. */
438 if (GET_CODE (SET_DEST (pattern
)) == CC0
439 && GET_CODE (SET_SRC (pattern
)) != COMPARE
)
440 this->success
.first
->enforce_mode
= 1;
445 case STRICT_LOW_PART
:
447 new = add_to_sequence (XEXP (pattern
, 0), &new->success
, newpos
);
448 this->success
.first
->enforce_mode
= 1;
452 this->test_elt_one_int
= 1;
453 this->elt_one_int
= XINT (pattern
, 1);
455 new = add_to_sequence (XEXP (pattern
, 0), &new->success
, newpos
);
456 this->success
.first
->enforce_mode
= 1;
462 new = add_to_sequence (XEXP (pattern
, 0), &new->success
, newpos
);
463 this->success
.first
->enforce_mode
= 1;
465 new = add_to_sequence (XEXP (pattern
, 1), &new->success
, newpos
);
467 new = add_to_sequence (XEXP (pattern
, 2), &new->success
, newpos
);
470 case EQ
: case NE
: case LE
: case LT
: case GE
: case GT
:
471 case LEU
: case LTU
: case GEU
: case GTU
:
472 /* If the first operand is (cc0), we don't have to do anything
474 if (GET_CODE (XEXP (pattern
, 0)) == CC0
)
477 /* ... fall through ... */
480 /* Enforce the mode on the first operand to avoid ambiguous insns. */
482 new = add_to_sequence (XEXP (pattern
, 0), &new->success
, newpos
);
483 this->success
.first
->enforce_mode
= 1;
485 new = add_to_sequence (XEXP (pattern
, 1), &new->success
, newpos
);
489 fmt
= GET_RTX_FORMAT (code
);
490 len
= GET_RTX_LENGTH (code
);
491 for (i
= 0; i
< len
; i
++)
493 newpos
[depth
] = '0' + i
;
494 if (fmt
[i
] == 'e' || fmt
[i
] == 'u')
495 new = add_to_sequence (XEXP (pattern
, i
), &new->success
, newpos
);
496 else if (fmt
[i
] == 'i' && i
== 0)
498 this->test_elt_zero_int
= 1;
499 this->elt_zero_int
= XINT (pattern
, i
);
501 else if (fmt
[i
] == 'i' && i
== 1)
503 this->test_elt_one_int
= 1;
504 this->elt_one_int
= XINT (pattern
, i
);
506 else if (fmt
[i
] == 'E')
509 /* We do not handle a vector appearing as other than
510 the first item, just because nothing uses them
511 and by handling only the special case
512 we can use one element in newpos for either
513 the item number of a subexpression
514 or the element number in a vector. */
517 this->veclen
= XVECLEN (pattern
, i
);
518 for (j
= 0; j
< XVECLEN (pattern
, i
); j
++)
520 newpos
[depth
] = 'a' + j
;
521 new = add_to_sequence (XVECEXP (pattern
, i
, j
),
522 &new->success
, newpos
);
525 else if (fmt
[i
] != '0')
531 /* Return 1 if we can prove that there is no RTL that can match both
532 D1 and D2. Otherwise, return 0 (it may be that there is an RTL that
533 can match both or just that we couldn't prove there wasn't such an RTL).
535 TOPLEVEL is non-zero if we are to only look at the top level and not
536 recursively descend. */
539 not_both_true (d1
, d2
, toplevel
)
540 struct decision
*d1
, *d2
;
543 struct decision
*p1
, *p2
;
545 /* If they are both to test modes and the modes are different, they aren't
546 both true. Similarly for codes, integer elements, and vector lengths. */
548 if ((d1
->enforce_mode
&& d2
->enforce_mode
549 && d1
->mode
!= VOIDmode
&& d2
->mode
!= VOIDmode
&& d1
->mode
!= d2
->mode
)
550 || (d1
->code
!= UNKNOWN
&& d2
->code
!= UNKNOWN
&& d1
->code
!= d2
->code
)
551 || (d1
->test_elt_zero_int
&& d2
->test_elt_zero_int
552 && d1
->elt_zero_int
!= d2
->elt_zero_int
)
553 || (d1
->test_elt_one_int
&& d2
->test_elt_one_int
554 && d1
->elt_one_int
!= d2
->elt_one_int
)
555 || (d1
->veclen
&& d2
->veclen
&& d1
->veclen
!= d2
->veclen
))
558 /* If either is a wild-card MATCH_OPERAND without a predicate, it can match
559 absolutely anything, so we can't say that no intersection is possible.
560 This case is detected by having a zero TESTS field with a code of
563 if ((d1
->tests
== 0 && d1
->code
== UNKNOWN
)
564 || (d2
->tests
== 0 && d2
->code
== UNKNOWN
))
567 /* If either has a predicate that we know something about, set things up so
568 that D1 is the one that always has a known predicate. Then see if they
569 have any codes in common. */
571 if (d1
->pred
>= 0 || d2
->pred
>= 0)
576 p1
= d1
, d1
= d2
, d2
= p1
;
578 /* If D2 tests an explicit code, see if it is in the list of valid codes
579 for D1's predicate. */
580 if (d2
->code
!= UNKNOWN
)
582 for (i
= 0; i
< NUM_RTX_CODE
&& preds
[d1
->pred
].codes
[i
]; i
++)
583 if (preds
[d1
->pred
].codes
[i
] == d2
->code
)
586 if (preds
[d1
->pred
].codes
[i
] == 0)
590 /* Otherwise see if the predicates have any codes in common. */
592 else if (d2
->pred
>= 0)
594 for (i
= 0; i
< NUM_RTX_CODE
&& preds
[d1
->pred
].codes
[i
]; i
++)
596 for (j
= 0; j
< NUM_RTX_CODE
; j
++)
597 if (preds
[d2
->pred
].codes
[j
] == 0
598 || preds
[d2
->pred
].codes
[j
] == preds
[d1
->pred
].codes
[i
])
601 if (preds
[d2
->pred
].codes
[j
] != 0)
605 if (preds
[d1
->pred
].codes
[i
] == 0)
610 /* If we got here, we can't prove that D1 and D2 cannot both be true.
611 If we are only to check the top level, return 0. Otherwise, see if
612 we can prove that all choices in both successors are mutually
613 exclusive. If either does not have any successors, we can't prove
614 they can't both be true. */
616 if (toplevel
|| d1
->success
.first
== 0 || d2
->success
.first
== 0)
619 for (p1
= d1
->success
.first
; p1
; p1
= p1
->next
)
620 for (p2
= d2
->success
.first
; p2
; p2
= p2
->next
)
621 if (! not_both_true (p1
, p2
, 0))
627 /* Assuming that we can reorder all the alternatives at a specific point in
628 the tree (see discussion in merge_trees), we would prefer an ordering of
629 nodes where groups of consecutive nodes test the same mode and, within each
630 mode, groups of nodes test the same code. With this order, we can
631 construct nested switch statements, the inner one to test the code and
632 the outer one to test the mode.
634 We would like to list nodes testing for specific codes before those
635 that test predicates to avoid unnecessary function calls. Similarly,
636 tests for specific modes should precede nodes that allow any mode.
638 This function returns the merit (with 0 being the best) of inserting
639 a test involving the specified MODE and CODE after node P. If P is
640 zero, we are to determine the merit of inserting the test at the front
644 position_merit (p
, mode
, code
)
646 enum machine_mode mode
;
649 enum machine_mode p_mode
;
651 /* The only time the front of the list is anything other than the worst
652 position is if we are testing a mode that isn't VOIDmode. */
654 return mode
== VOIDmode
? 3 : 2;
656 p_mode
= p
->enforce_mode
? p
->mode
: VOIDmode
;
658 /* The best case is if the codes and modes both match. */
659 if (p_mode
== mode
&& p
->code
== code
)
662 /* If the codes don't match, the next best case is if the modes match.
663 In that case, the best position for this node depends on whether
664 we are testing for a specific code or not. If we are, the best place
665 is after some other test for an explicit code and our mode or after
666 the last test in the previous mode if every test in our mode is for
669 If we are testing for UNKNOWN, then the next best case is at the end of
673 && ((p_mode
== mode
&& p
->code
!= UNKNOWN
)
674 || (p_mode
!= mode
&& p
->next
675 && (p
->next
->enforce_mode
? p
->next
->mode
: VOIDmode
) == mode
676 && (p
->next
->code
== UNKNOWN
))))
677 || (code
== UNKNOWN
&& p_mode
== mode
679 || (p
->next
->enforce_mode
? p
->next
->mode
: VOIDmode
) != mode
)))
682 /* The third best case occurs when nothing is testing MODE. If MODE
683 is not VOIDmode, then the third best case is after something of any
684 mode that is not VOIDmode. If we are testing VOIDmode, the third best
685 place is the end of the list. */
688 && ((mode
!= VOIDmode
&& p_mode
!= VOIDmode
)
689 || (mode
== VOIDmode
&& p
->next
== 0)))
692 /* Otherwise, we have the worst case. */
696 /* Merge two decision tree listheads OLDH and ADDH,
697 modifying OLDH destructively, and return the merged tree. */
699 static struct decision_head
700 merge_trees (oldh
, addh
)
701 register struct decision_head oldh
, addh
;
703 struct decision
*add
, *next
;
711 /* If we are adding things at different positions, something is wrong. */
712 if (strcmp (oldh
.first
->position
, addh
.first
->position
))
715 for (add
= addh
.first
; add
; add
= next
)
717 enum machine_mode add_mode
= add
->enforce_mode
? add
->mode
: VOIDmode
;
718 struct decision
*best_position
= 0;
720 struct decision
*old
;
724 /* The semantics of pattern matching state that the tests are done in
725 the order given in the MD file so that if an insn matches two
726 patterns, the first one will be used. However, in practice, most,
727 if not all, patterns are unambiguous so that their order is
728 independent. In that case, we can merge identical tests and
729 group all similar modes and codes together.
731 Scan starting from the end of OLDH until we reach a point
732 where we reach the head of the list or where we pass a pattern
733 that could also be true if NEW is true. If we find an identical
734 pattern, we can merge them. Also, record the last node that tests
735 the same code and mode and the last one that tests just the same mode.
737 If we have no match, place NEW after the closest match we found. */
739 for (old
= oldh
.last
; old
; old
= old
->prev
)
743 /* If we don't have anything to test except an additional test,
744 do not consider the two nodes equal. If we did, the test below
745 would cause an infinite recursion. */
746 if (old
->tests
== 0 && old
->test_elt_zero_int
== 0
747 && old
->test_elt_one_int
== 0 && old
->veclen
== 0
748 && old
->dupno
== -1 && old
->mode
== VOIDmode
749 && old
->code
== UNKNOWN
750 && (old
->c_test
!= 0 || add
->c_test
!= 0))
753 else if ((old
->tests
== add
->tests
754 || (old
->pred
>= 0 && old
->pred
== add
->pred
)
755 || (old
->tests
&& add
->tests
756 && !strcmp (old
->tests
, add
->tests
)))
757 && old
->test_elt_zero_int
== add
->test_elt_zero_int
758 && old
->elt_zero_int
== add
->elt_zero_int
759 && old
->test_elt_one_int
== add
->test_elt_one_int
760 && old
->elt_one_int
== add
->elt_one_int
761 && old
->veclen
== add
->veclen
762 && old
->dupno
== add
->dupno
763 && old
->opno
== add
->opno
764 && old
->code
== add
->code
765 && old
->enforce_mode
== add
->enforce_mode
766 && old
->mode
== add
->mode
)
768 /* If the additional test is not the same, split both nodes
769 into nodes that just contain all things tested before the
770 additional test and nodes that contain the additional test
771 and actions when it is true. This optimization is important
772 because of the case where we have almost identical patterns
773 with different tests on target flags. */
775 if (old
->c_test
!= add
->c_test
776 && ! (old
->c_test
&& add
->c_test
777 && !strcmp (old
->c_test
, add
->c_test
)))
779 if (old
->insn_code_number
>= 0 || old
->opno
>= 0)
781 struct decision
*split
782 = (struct decision
*) xmalloc (sizeof (struct decision
));
784 mybcopy (old
, split
, sizeof (struct decision
));
786 old
->success
.first
= old
->success
.last
= split
;
789 old
->insn_code_number
= -1;
790 old
->num_clobbers_to_add
= 0;
792 split
->number
= next_number
++;
793 split
->next
= split
->prev
= 0;
794 split
->mode
= VOIDmode
;
795 split
->code
= UNKNOWN
;
797 split
->test_elt_zero_int
= 0;
798 split
->test_elt_one_int
= 0;
803 if (add
->insn_code_number
>= 0 || add
->opno
>= 0)
805 struct decision
*split
806 = (struct decision
*) xmalloc (sizeof (struct decision
));
808 mybcopy (add
, split
, sizeof (struct decision
));
810 add
->success
.first
= add
->success
.last
= split
;
813 add
->insn_code_number
= -1;
814 add
->num_clobbers_to_add
= 0;
816 split
->number
= next_number
++;
817 split
->next
= split
->prev
= 0;
818 split
->mode
= VOIDmode
;
819 split
->code
= UNKNOWN
;
821 split
->test_elt_zero_int
= 0;
822 split
->test_elt_one_int
= 0;
828 if (old
->insn_code_number
>= 0 && add
->insn_code_number
>= 0)
830 /* If one node is for a normal insn and the second is
831 for the base insn with clobbers stripped off, the
832 second node should be ignored. */
834 if (old
->num_clobbers_to_add
== 0
835 && add
->num_clobbers_to_add
> 0)
836 /* Nothing to do here. */
838 else if (old
->num_clobbers_to_add
> 0
839 && add
->num_clobbers_to_add
== 0)
841 /* In this case, replace OLD with ADD. */
842 old
->insn_code_number
= add
->insn_code_number
;
843 old
->num_clobbers_to_add
= 0;
846 fatal ("Two actions at one point in tree");
849 if (old
->insn_code_number
== -1)
850 old
->insn_code_number
= add
->insn_code_number
;
851 old
->success
= merge_trees (old
->success
, add
->success
);
856 /* Unless we have already found the best possible insert point,
857 see if this position is better. If so, record it. */
860 && ((our_merit
= position_merit (old
, add_mode
, add
->code
))
862 best_merit
= our_merit
, best_position
= old
;
864 if (! not_both_true (old
, add
, 0))
868 /* If ADD was duplicate, we are done. */
872 /* Otherwise, find the best place to insert ADD. Normally this is
873 BEST_POSITION. However, if we went all the way to the top of
874 the list, it might be better to insert at the top. */
876 if (best_position
== 0)
879 if (old
== 0 && position_merit (0, add_mode
, add
->code
) < best_merit
)
882 add
->next
= oldh
.first
;
883 oldh
.first
->prev
= add
;
889 add
->prev
= best_position
;
890 add
->next
= best_position
->next
;
891 best_position
->next
= add
;
892 if (best_position
== oldh
.last
)
895 add
->next
->prev
= add
;
902 /* Count the number of subnodes of HEAD. If the number is high enough,
903 make the first node in HEAD start a separate subroutine in the C code
906 TYPE gives the type of routine we are writing.
908 INITIAL is non-zero if this is the highest-level node. We never write
912 break_out_subroutines (head
, type
, initial
)
913 struct decision_head head
;
914 enum routine_type type
;
918 struct decision
*node
, *sub
;
920 for (sub
= head
.first
; sub
; sub
= sub
->next
)
921 size
+= 1 + break_out_subroutines (sub
->success
, type
, 0);
923 if (size
> SUBROUTINE_THRESHOLD
&& ! initial
)
925 head
.first
->subroutine_number
= ++next_subroutine_number
;
926 write_subroutine (head
.first
, type
);
932 /* Write out a subroutine of type TYPE to do comparisons starting at node
936 write_subroutine (tree
, type
)
937 struct decision
*tree
;
938 enum routine_type type
;
943 printf ("rtx\nsplit");
945 printf ("int\nrecog");
947 if (tree
!= 0 && tree
->subroutine_number
> 0)
948 printf ("_%d", tree
->subroutine_number
);
949 else if (type
== SPLIT
)
952 printf (" (x0, insn");
954 printf (", pnum_clobbers");
957 printf (" register rtx x0;\n rtx insn;\n");
959 printf (" int *pnum_clobbers;\n");
962 printf (" register rtx *ro = &recog_operand[0];\n");
964 printf (" register rtx ");
965 for (i
= 1; i
< max_depth
; i
++)
968 printf ("x%d;\n", max_depth
);
969 printf (" %s tem;\n", type
== SPLIT
? "rtx" : "int");
970 write_tree (tree
, "", 0, 1, type
);
971 printf (" ret0: return %d;\n}\n\n", type
== SPLIT
? 0 : -1);
974 /* This table is used to indent the recog_* functions when we are inside
975 conditions or switch statements. We only support small indentations
976 and always indent at least two spaces. */
978 static char *indents
[]
979 = {" ", " ", " ", " ", " ", " ", " ", " ",
980 "\t", "\t ", "\t ", "\t ", "\t ", "\t ", "\t ",
981 "\t\t", "\t\t ", "\t\t ", "\t\t ", "\t\t ", "\t\t "};
983 /* Write out C code to perform the decisions in TREE for a subroutine of
984 type TYPE. If all of the choices fail, branch to node AFTERWARD, if
985 non-zero, otherwise return. PREVPOS is the position of the node that
986 branched to this test.
988 When we merged all alternatives, we tried to set up a convenient order.
989 Specifically, tests involving the same mode are all grouped together,
990 followed by a group that does not contain a mode test. Within each group
991 of the same mode, we also group tests with the same code, followed by a
992 group that does not test a code.
994 Occasionally, we cannot arbitrarily reorder the tests so that multiple
995 sequence of groups as described above are present.
997 We generate two nested switch statements, the outer statement for
998 testing modes, and the inner switch for testing RTX codes. It is
999 not worth optimizing cases when only a small number of modes or
1000 codes is tested, since the compiler can do that when compiling the
1001 resulting function. We do check for when every test is the same mode
1005 write_tree_1 (tree
, prevpos
, afterward
, type
)
1006 struct decision
*tree
;
1008 struct decision
*afterward
;
1009 enum routine_type type
;
1011 register struct decision
*p
, *p1
;
1012 register int depth
= tree
? strlen (tree
->position
) : 0;
1013 enum machine_mode switch_mode
= VOIDmode
;
1014 RTX_CODE switch_code
= UNKNOWN
;
1016 char modemap
[NUM_MACHINE_MODES
];
1017 char codemap
[NUM_RTX_CODE
];
1021 /* One tricky area is what is the exact state when we branch to a
1022 node's label. There are two cases where we branch: when looking at
1023 successors to a node, or when a set of tests fails.
1025 In the former case, we are always branching to the first node in a
1026 decision list and we want all required tests to be performed. We
1027 put the labels for such nodes in front of any switch or test statements.
1028 These branches are done without updating the position to that of the
1031 In the latter case, we are branching to a node that is not the first
1032 node in a decision list. We have already checked that it is possible
1033 for both the node we originally tested at this level and the node we
1034 are branching to to be both match some pattern. That means that they
1035 usually will be testing the same mode and code. So it is normally safe
1036 for such labels to be inside switch statements, since the tests done
1037 by virtue of arriving at that label will usually already have been
1038 done. The exception is a branch from a node that does not test a
1039 mode or code to one that does. In such cases, we set the `retest_mode'
1040 or `retest_code' flags. That will ensure that we start a new switch
1041 at that position and put the label before the switch.
1043 The branches in the latter case must set the position to that of the
1048 if (tree
&& tree
->subroutine_number
== 0)
1050 printf (" L%d:\n", tree
->number
);
1051 tree
->label_needed
= 0;
1056 change_state (prevpos
, tree
->position
, 2);
1057 prevpos
= tree
->position
;
1060 for (p
= tree
; p
; p
= p
->next
)
1062 enum machine_mode mode
= p
->enforce_mode
? p
->mode
: VOIDmode
;
1064 int wrote_bracket
= 0;
1067 if (p
->success
.first
== 0 && p
->insn_code_number
< 0)
1070 /* Find the next alternative to p that might be true when p is true.
1071 Test that one next if p's successors fail. */
1073 for (p1
= p
->next
; p1
&& not_both_true (p
, p1
, 1); p1
= p1
->next
)
1079 if (mode
== VOIDmode
&& p1
->enforce_mode
&& p1
->mode
!= VOIDmode
)
1080 p1
->retest_mode
= 1;
1081 if (p
->code
== UNKNOWN
&& p1
->code
!= UNKNOWN
)
1082 p1
->retest_code
= 1;
1083 p1
->label_needed
= 1;
1086 /* If we have a different code or mode than the last node and
1087 are in a switch on codes, we must either end the switch or
1088 go to another case. We must also end the switch if this
1089 node needs a label and to retest either the mode or code. */
1091 if (switch_code
!= UNKNOWN
1092 && (switch_code
!= p
->code
|| switch_mode
!= mode
1093 || (p
->label_needed
&& (p
->retest_mode
|| p
->retest_code
))))
1095 enum rtx_code code
= p
->code
;
1097 /* If P is testing a predicate that we know about and we haven't
1098 seen any of the codes that are valid for the predicate, we
1099 can write a series of "case" statement, one for each possible
1100 code. Since we are already in a switch, these redundant tests
1101 are very cheap and will reduce the number of predicate called. */
1105 for (i
= 0; i
< NUM_RTX_CODE
&& preds
[p
->pred
].codes
[i
]; i
++)
1106 if (codemap
[(int) preds
[p
->pred
].codes
[i
]])
1109 if (preds
[p
->pred
].codes
[i
] == 0)
1110 code
= MATCH_OPERAND
;
1113 if (code
== UNKNOWN
|| codemap
[(int) code
]
1114 || switch_mode
!= mode
1115 || (p
->label_needed
&& (p
->retest_mode
|| p
->retest_code
)))
1117 printf ("%s}\n", indents
[indent
- 2]);
1118 switch_code
= UNKNOWN
;
1124 printf ("%sbreak;\n", indents
[indent
]);
1126 if (code
== MATCH_OPERAND
)
1128 for (i
= 0; i
< NUM_RTX_CODE
&& preds
[p
->pred
].codes
[i
]; i
++)
1130 printf ("%scase ", indents
[indent
- 2]);
1131 print_code (preds
[p
->pred
].codes
[i
]);
1133 codemap
[(int) preds
[p
->pred
].codes
[i
]] = 1;
1138 printf ("%scase ", indents
[indent
- 2]);
1141 codemap
[(int) p
->code
] = 1;
1150 /* If we were previously in a switch on modes and now have a different
1151 mode, end at least the case, and maybe end the switch if we are
1152 not testing a mode or testing a mode whose case we already saw. */
1154 if (switch_mode
!= VOIDmode
1155 && (switch_mode
!= mode
|| (p
->label_needed
&& p
->retest_mode
)))
1157 if (mode
== VOIDmode
|| modemap
[(int) mode
]
1158 || (p
->label_needed
&& p
->retest_mode
))
1160 printf ("%s}\n", indents
[indent
- 2]);
1161 switch_mode
= VOIDmode
;
1167 printf (" break;\n");
1168 printf (" case %smode:\n", GET_MODE_NAME (mode
));
1170 modemap
[(int) mode
] = 1;
1176 /* If we are about to write dead code, something went wrong. */
1177 if (! p
->label_needed
&& uncond
)
1180 /* If we need a label and we will want to retest the mode or code at
1181 that label, write the label now. We have already ensured that
1182 things will be valid for the test. */
1184 if (p
->label_needed
&& (p
->retest_mode
|| p
->retest_code
))
1186 printf ("%sL%d:\n", indents
[indent
- 2], p
->number
);
1187 p
->label_needed
= 0;
1192 /* If we are not in any switches, see if we can shortcut things
1193 by checking for identical modes and codes. */
1195 if (switch_mode
== VOIDmode
&& switch_code
== UNKNOWN
)
1197 /* If p and its alternatives all want the same mode,
1198 reject all others at once, first, then ignore the mode. */
1200 if (mode
!= VOIDmode
&& p
->next
&& same_modes (p
, mode
))
1202 printf (" if (GET_MODE (x%d) != %smode)\n",
1203 depth
, GET_MODE_NAME (p
->mode
));
1207 change_state (p
->position
, afterward
->position
, 6);
1208 printf (" goto L%d;\n }\n", afterward
->number
);
1211 printf (" goto ret0;\n");
1216 /* If p and its alternatives all want the same code,
1217 reject all others at once, first, then ignore the code. */
1219 if (p
->code
!= UNKNOWN
&& p
->next
&& same_codes (p
, p
->code
))
1221 printf (" if (GET_CODE (x%d) != ", depth
);
1222 print_code (p
->code
);
1227 change_state (p
->position
, afterward
->position
, indent
+ 4);
1228 printf (" goto L%d;\n }\n", afterward
->number
);
1231 printf (" goto ret0;\n");
1236 /* If we are not in a mode switch and we are testing for a specific
1237 mode, start a mode switch unless we have just one node or the next
1238 node is not testing a mode (we have already tested for the case of
1239 more than one mode, but all of the same mode). */
1241 if (switch_mode
== VOIDmode
&& mode
!= VOIDmode
&& p
->next
!= 0
1242 && p
->next
->enforce_mode
&& p
->next
->mode
!= VOIDmode
)
1244 mybzero (modemap
, sizeof modemap
);
1245 printf ("%sswitch (GET_MODE (x%d))\n", indents
[indent
], depth
);
1246 printf ("%s{\n", indents
[indent
+ 2]);
1248 printf ("%scase %smode:\n", indents
[indent
- 2],
1249 GET_MODE_NAME (mode
));
1250 modemap
[(int) mode
] = 1;
1254 /* Similarly for testing codes. */
1256 if (switch_code
== UNKNOWN
&& p
->code
!= UNKNOWN
&& ! p
->ignore_code
1257 && p
->next
!= 0 && p
->next
->code
!= UNKNOWN
)
1259 mybzero (codemap
, sizeof codemap
);
1260 printf ("%sswitch (GET_CODE (x%d))\n", indents
[indent
], depth
);
1261 printf ("%s{\n", indents
[indent
+ 2]);
1263 printf ("%scase ", indents
[indent
- 2]);
1264 print_code (p
->code
);
1266 codemap
[(int) p
->code
] = 1;
1267 switch_code
= p
->code
;
1270 /* Now that most mode and code tests have been done, we can write out
1271 a label for an inner node, if we haven't already. */
1272 if (p
->label_needed
)
1273 printf ("%sL%d:\n", indents
[indent
- 2], p
->number
);
1275 inner_indent
= indent
;
1277 /* The only way we can have to do a mode or code test here is if
1278 this node needs such a test but is the only node to be tested.
1279 In that case, we won't have started a switch. Note that this is
1280 the only way the switch and test modes can disagree. */
1282 if ((mode
!= switch_mode
&& ! p
->ignore_mode
)
1283 || (p
->code
!= switch_code
&& p
->code
!= UNKNOWN
&& ! p
->ignore_code
)
1284 || p
->test_elt_zero_int
|| p
->test_elt_one_int
|| p
->veclen
1285 || p
->dupno
>= 0 || p
->tests
|| p
->num_clobbers_to_add
)
1287 printf ("%sif (", indents
[indent
]);
1289 if (mode
!= switch_mode
&& ! p
->ignore_mode
)
1290 printf ("GET_MODE (x%d) == %smode && ",
1291 depth
, GET_MODE_NAME (mode
));
1292 if (p
->code
!= switch_code
&& p
->code
!= UNKNOWN
&& ! p
->ignore_code
)
1294 printf ("GET_CODE (x%d) == ", depth
);
1295 print_code (p
->code
);
1299 if (p
->test_elt_zero_int
)
1300 printf ("XINT (x%d, 0) == %d && ", depth
, p
->elt_zero_int
);
1301 if (p
->test_elt_one_int
)
1302 printf ("XINT (x%d, 1) == %d && ", depth
, p
->elt_one_int
);
1304 printf ("XVECLEN (x%d, 0) == %d && ", depth
, p
->veclen
);
1306 printf ("rtx_equal_p (x%d, ro[%d]) && ", depth
, p
->dupno
);
1307 if (p
->num_clobbers_to_add
)
1308 printf ("pnum_clobbers != 0 && ");
1310 printf ("%s (x%d, %smode)", p
->tests
, depth
,
1311 GET_MODE_NAME (p
->mode
));
1321 need_bracket
= ! uncond
;
1327 printf ("%s{\n", indents
[inner_indent
]);
1333 printf ("%sro[%d] = x%d;\n", indents
[inner_indent
], p
->opno
, depth
);
1338 printf ("%sif (%s)\n", indents
[inner_indent
], p
->c_test
);
1344 if (p
->insn_code_number
>= 0)
1347 printf ("%sreturn gen_split_%d (operands);\n",
1348 indents
[inner_indent
], p
->insn_code_number
);
1351 if (p
->num_clobbers_to_add
)
1355 printf ("%s{\n", indents
[inner_indent
]);
1359 printf ("%s*pnum_clobbers = %d;\n",
1360 indents
[inner_indent
], p
->num_clobbers_to_add
);
1361 printf ("%sreturn %d;\n",
1362 indents
[inner_indent
], p
->insn_code_number
);
1367 printf ("%s}\n", indents
[inner_indent
]);
1371 printf ("%sreturn %d;\n",
1372 indents
[inner_indent
], p
->insn_code_number
);
1376 printf ("%sgoto L%d;\n", indents
[inner_indent
],
1377 p
->success
.first
->number
);
1380 printf ("%s}\n", indents
[inner_indent
- 2]);
1383 /* We have now tested all alternatives. End any switches we have open
1384 and branch to the alternative node unless we know that we can't fall
1385 through to the branch. */
1387 if (switch_code
!= UNKNOWN
)
1389 printf ("%s}\n", indents
[indent
- 2]);
1394 if (switch_mode
!= VOIDmode
)
1396 printf ("%s}\n", indents
[indent
- 2]);
1409 change_state (prevpos
, afterward
->position
, 2);
1410 printf (" goto L%d;\n", afterward
->number
);
1413 printf (" goto ret0;\n");
1421 for (p1
= GET_RTX_NAME (code
); *p1
; p1
++)
1423 if (*p1
>= 'a' && *p1
<= 'z')
1424 putchar (*p1
+ 'A' - 'a');
1431 same_codes (p
, code
)
1432 register struct decision
*p
;
1433 register RTX_CODE code
;
1435 for (; p
; p
= p
->next
)
1436 if (p
->code
!= code
)
1444 register struct decision
*p
;
1446 for (; p
; p
= p
->next
)
1451 same_modes (p
, mode
)
1452 register struct decision
*p
;
1453 register enum machine_mode mode
;
1455 for (; p
; p
= p
->next
)
1456 if ((p
->enforce_mode
? p
->mode
: VOIDmode
) != mode
)
1464 register struct decision
*p
;
1466 for (; p
; p
= p
->next
)
1467 p
->enforce_mode
= 0;
1470 /* Write out the decision tree starting at TREE for a subroutine of type TYPE.
1472 PREVPOS is the position at the node that branched to this node.
1474 INITIAL is nonzero if this is the first node we are writing in a subroutine.
1476 If all nodes are false, branch to the node AFTERWARD. */
1479 write_tree (tree
, prevpos
, afterward
, initial
, type
)
1480 struct decision
*tree
;
1482 struct decision
*afterward
;
1484 enum routine_type type
;
1486 register struct decision
*p
;
1487 char *name_prefix
= (type
== SPLIT
? "split" : "recog");
1488 char *call_suffix
= (type
== SPLIT
? "" : ", pnum_clobbers");
1490 if (! initial
&& tree
->subroutine_number
> 0)
1492 printf (" L%d:\n", tree
->number
);
1496 printf (" tem = %s_%d (x0, insn%s);\n",
1497 name_prefix
, tree
->subroutine_number
, call_suffix
);
1498 printf (" if (tem >= 0) return tem;\n");
1499 change_state (tree
->position
, afterward
->position
, 2);
1500 printf (" goto L%d;\n", afterward
->number
);
1503 printf (" return %s_%d (x0, insn%s);\n",
1504 name_prefix
, tree
->subroutine_number
, call_suffix
);
1508 write_tree_1 (tree
, prevpos
, afterward
, type
);
1510 for (p
= tree
; p
; p
= p
->next
)
1511 if (p
->success
.first
)
1512 write_tree (p
->success
.first
, p
->position
,
1513 p
->afterward
? p
->afterward
: afterward
, 0, type
);
1517 /* Assuming that the state of argument is denoted by OLDPOS, take whatever
1518 actions are necessary to move to NEWPOS.
1520 INDENT says how many blanks to place at the front of lines. */
1523 change_state (oldpos
, newpos
, indent
)
1528 int odepth
= strlen (oldpos
);
1530 int ndepth
= strlen (newpos
);
1532 /* Pop up as many levels as necessary. */
1534 while (strncmp (oldpos
, newpos
, depth
))
1537 /* Go down to desired level. */
1539 while (depth
< ndepth
)
1541 if (newpos
[depth
] >= 'a' && newpos
[depth
] <= 'z')
1542 printf ("%sx%d = XVECEXP (x%d, 0, %d);\n",
1543 indents
[indent
], depth
+ 1, depth
, newpos
[depth
] - 'a');
1545 printf ("%sx%d = XEXP (x%d, %c);\n",
1546 indents
[indent
], depth
+ 1, depth
, newpos
[depth
]);
1560 tem
= (char *) xmalloc (strlen (s1
) + 1);
1569 register unsigned length
;
1571 while (length
-- > 0)
1576 mybcopy (in
, out
, length
)
1577 register char *in
, *out
;
1578 register unsigned length
;
1580 while (length
-- > 0)
1595 tem
= (char *) xmalloc (strlen (s1
) + strlen (s2
) + 2);
1604 xrealloc (ptr
, size
)
1608 char *result
= (char *) realloc (ptr
, size
);
1610 fatal ("virtual memory exhausted");
1618 register char *val
= (char *) malloc (size
);
1621 fatal ("virtual memory exhausted");
1629 fprintf (stderr
, "genrecog: ");
1630 fprintf (stderr
, s
, a1
, a2
);
1631 fprintf (stderr
, "\n");
1632 fprintf (stderr
, "after %d definitions\n", next_index
);
1633 exit (FATAL_EXIT_CODE
);
1636 /* More 'friendly' abort that prints the line and file.
1637 config.h can #define abort fancy_abort if you like that sort of thing. */
1642 fatal ("Internal gcc abort.");
1651 struct decision_head recog_tree
;
1652 struct decision_head split_tree
;
1656 obstack_init (rtl_obstack
);
1657 recog_tree
.first
= recog_tree
.last
= split_tree
.first
= split_tree
.last
= 0;
1660 fatal ("No input file name.");
1662 infile
= fopen (argv
[1], "r");
1666 exit (FATAL_EXIT_CODE
);
1673 printf ("/* Generated automatically by the program `genrecog'\n\
1674 from the machine description file `md'. */\n\n");
1676 printf ("#include \"config.h\"\n");
1677 printf ("#include \"rtl.h\"\n");
1678 printf ("#include \"insn-config.h\"\n");
1679 printf ("#include \"recog.h\"\n");
1680 printf ("#include \"real.h\"\n");
1681 printf ("#include \"output.h\"\n");
1682 printf ("#include \"flags.h\"\n");
1685 /* Read the machine description. */
1689 c
= read_skip_spaces (infile
);
1694 desc
= read_rtx (infile
);
1695 if (GET_CODE (desc
) == DEFINE_INSN
)
1696 recog_tree
= merge_trees (recog_tree
,
1697 make_insn_sequence (desc
, RECOG
));
1698 else if (GET_CODE (desc
) == DEFINE_SPLIT
)
1699 split_tree
= merge_trees (split_tree
,
1700 make_insn_sequence (desc
, SPLIT
));
1701 if (GET_CODE (desc
) == DEFINE_PEEPHOLE
1702 || GET_CODE (desc
) == DEFINE_EXPAND
)
1708 /* `recog' contains a decision tree\n\
1709 that recognizes whether the rtx X0 is a valid instruction.\n\
1711 recog returns -1 if the rtx is not valid.\n\
1712 If the rtx is valid, recog returns a nonnegative number\n\
1713 which is the insn code number for the pattern that matched.\n");
1714 printf (" This is the same as the order in the machine description of\n\
1715 the entry that matched. This number can be used as an index into\n\
1716 entry that matched. This number can be used as an index into various\n\
1717 insn_* tables, such as insn_templates, insn_outfun, and insn_n_operands\n\
1718 (found in insn-output.c).\n\n");
1719 printf (" The third argument to recog is an optional pointer to an int.\n\
1720 If present, recog will accept a pattern if it matches except for\n\
1721 missing CLOBBER expressions at the end. In that case, the value\n\
1722 pointed to by the optional pointer will be set to the number of\n\
1723 CLOBBERs that need to be added (it should be initialized to zero by\n\
1724 the caller). If it is set nonzero, the caller should allocate a\n\
1725 PARALLEL of the appropriate size, copy the initial entries, and call\n\
1726 add_clobbers (found in insn-emit.c) to fill in the CLOBBERs.");
1728 if (split_tree
.first
)
1729 printf ("\n\n The function split_insns returns 0 if the rtl could not\n\
1730 be split or the split rtl in a SEQUENCE if it can be.");
1734 printf ("rtx recog_operand[MAX_RECOG_OPERANDS];\n\n");
1735 printf ("rtx *recog_operand_loc[MAX_RECOG_OPERANDS];\n\n");
1736 printf ("rtx *recog_dup_loc[MAX_DUP_OPERANDS];\n\n");
1737 printf ("char recog_dup_num[MAX_DUP_OPERANDS];\n\n");
1738 printf ("#define operands recog_operand\n\n");
1740 next_subroutine_number
= 0;
1741 break_out_subroutines (recog_tree
, RECOG
, 1);
1742 write_subroutine (recog_tree
.first
, RECOG
);
1744 next_subroutine_number
= 0;
1745 break_out_subroutines (split_tree
, SPLIT
, 1);
1746 write_subroutine (split_tree
.first
, SPLIT
);
1749 exit (ferror (stdout
) != 0 ? FATAL_EXIT_CODE
: SUCCESS_EXIT_CODE
);