1 /* Generate code from machine description to recognize rtl as insns.
2 Copyright (C) 1987, 1988, 1992, 1993, 1994, 1995, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, 2009
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it
9 under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3, or (at your option)
13 GCC is distributed in the hope that it will be useful, but WITHOUT
14 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
16 License for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
23 /* This program is used to produce insn-recog.c, which contains a
24 function called `recog' plus its subroutines. These functions
25 contain a decision tree that recognizes whether an rtx, the
26 argument given to recog, is a valid instruction.
28 recog returns -1 if the rtx is not valid. If the rtx is valid,
29 recog returns a nonnegative number which is the insn code number
30 for the pattern that matched. This is the same as the order in the
31 machine description of the entry that matched. This number can be
32 used as an index into various insn_* tables, such as insn_template,
33 insn_outfun, and insn_n_operands (found in insn-output.c).
35 The third argument to recog is an optional pointer to an int. If
36 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
42 call add_clobbers (found in insn-emit.c) to fill in the CLOBBERs.
44 This program also generates the function `split_insns', which
45 returns 0 if the rtl could not be split, or it returns the split
48 This program also generates the function `peephole2_insns', which
49 returns 0 if the rtl could not be matched. If there was a match,
50 the new rtl is returned in an INSN list, and LAST_INSN will point
51 to the last recognized insn in the old sequence. */
55 #include "coretypes.h"
59 #include "gensupport.h"
61 #define OUTPUT_LABEL(INDENT_STRING, LABEL_NUMBER) \
62 printf("%sL%d: ATTRIBUTE_UNUSED_LABEL\n", (INDENT_STRING), (LABEL_NUMBER))
64 /* A listhead of decision trees. The alternatives to a node are kept
65 in a doubly-linked list so we can easily add nodes to the proper
66 place when merging. */
70 struct decision *first;
71 struct decision *last;
74 /* A single test. The two accept types aren't tests per-se, but
75 their equality (or lack thereof) does affect tree merging so
76 it is convenient to keep them here. */
80 /* A linked list through the tests attached to a node. */
81 struct decision_test *next;
83 /* These types are roughly in the order in which we'd like to test them. */
87 DT_mode, DT_code, DT_veclen,
88 DT_elt_zero_int, DT_elt_one_int, DT_elt_zero_wide, DT_elt_zero_wide_safe,
90 DT_veclen_ge, DT_dup, DT_pred, DT_c_test,
91 DT_accept_op, DT_accept_insn
96 int num_insns; /* Number if insn in a define_peephole2. */
97 enum machine_mode mode; /* Machine mode of node. */
98 RTX_CODE code; /* Code to test. */
102 const char *name; /* Predicate to call. */
103 const struct pred_data *data;
104 /* Optimization hints for this predicate. */
105 enum machine_mode mode; /* Machine mode for node. */
108 const char *c_test; /* Additional test to perform. */
109 int veclen; /* Length of vector. */
110 int dup; /* Number of operand to compare against. */
111 HOST_WIDE_INT intval; /* Value for XINT for XWINT. */
112 int opno; /* Operand number matched. */
115 int code_number; /* Insn number matched. */
116 int lineno; /* Line number of the insn. */
117 int num_clobbers_to_add; /* Number of CLOBBERs to be added. */
122 /* Data structure for decision tree for recognizing legitimate insns. */
126 struct decision_head success; /* Nodes to test on success. */
127 struct decision *next; /* Node to test on failure. */
128 struct decision *prev; /* Node whose failure tests us. */
129 struct decision *afterward; /* Node to test on success,
130 but failure of successor nodes. */
132 const char *position; /* String denoting position in pattern. */
134 struct decision_test *tests; /* The tests for this node. */
136 int number; /* Node number, used for labels */
137 int subroutine_number; /* Number of subroutine this node starts */
138 int need_label; /* Label needs to be output. */
141 #define SUBROUTINE_THRESHOLD 100
143 static int next_subroutine_number;
145 /* We can write three types of subroutines: One for insn recognition,
146 one to split insns, and one for peephole-type optimizations. This
147 defines which type is being written. */
150 RECOG, SPLIT, PEEPHOLE2
153 #define IS_SPLIT(X) ((X) != RECOG)
155 /* Next available node number for tree nodes. */
157 static int next_number;
159 /* Next number to use as an insn_code. */
161 static int next_insn_code;
163 /* Record the highest depth we ever have so we know how many variables to
164 allocate in each subroutine we make. */
166 static int max_depth;
168 /* The line number of the start of the pattern currently being processed. */
169 static int pattern_lineno;
171 /* Count of errors. */
172 static int error_count;
174 /* Predicate handling.
176 We construct from the machine description a table mapping each
177 predicate to a list of the rtl codes it can possibly match. The
178 function 'maybe_both_true' uses it to deduce that there are no
179 expressions that can be matches by certain pairs of tree nodes.
180 Also, if a predicate can match only one code, we can hardwire that
181 code into the node testing the predicate.
183 Some predicates are flagged as special. validate_pattern will not
184 warn about modeless match_operand expressions if they have a
185 special predicate. Predicates that allow only constants are also
186 treated as special, for this purpose.
188 validate_pattern will warn about predicates that allow non-lvalues
189 when they appear in destination operands.
191 Calculating the set of rtx codes that can possibly be accepted by a
192 predicate expression EXP requires a three-state logic: any given
193 subexpression may definitively accept a code C (Y), definitively
194 reject a code C (N), or may have an indeterminate effect (I). N
195 and I is N; Y or I is Y; Y and I, N or I are both I. Here are full
206 We represent Y with 1, N with 0, I with 2. If any code is left in
207 an I state by the complete expression, we must assume that that
208 code can be accepted. */
214 #define TRISTATE_AND(a,b) \
215 ((a) == I ? ((b) == N ? N : I) : \
216 (b) == I ? ((a) == N ? N : I) : \
219 #define TRISTATE_OR(a,b) \
220 ((a) == I ? ((b) == Y ? Y : I) : \
221 (b) == I ? ((a) == Y ? Y : I) : \
224 #define TRISTATE_NOT(a) \
225 ((a) == I ? I : !(a))
227 /* 0 means no warning about that code yet, 1 means warned. */
228 static char did_you_mean_codes[NUM_RTX_CODE];
230 /* Recursively calculate the set of rtx codes accepted by the
231 predicate expression EXP, writing the result to CODES. */
233 compute_predicate_codes (rtx exp, char codes[NUM_RTX_CODE])
235 char op0_codes[NUM_RTX_CODE];
236 char op1_codes[NUM_RTX_CODE];
237 char op2_codes[NUM_RTX_CODE];
240 switch (GET_CODE (exp))
243 compute_predicate_codes (XEXP (exp, 0), op0_codes);
244 compute_predicate_codes (XEXP (exp, 1), op1_codes);
245 for (i = 0; i < NUM_RTX_CODE; i++)
246 codes[i] = TRISTATE_AND (op0_codes[i], op1_codes[i]);
250 compute_predicate_codes (XEXP (exp, 0), op0_codes);
251 compute_predicate_codes (XEXP (exp, 1), op1_codes);
252 for (i = 0; i < NUM_RTX_CODE; i++)
253 codes[i] = TRISTATE_OR (op0_codes[i], op1_codes[i]);
256 compute_predicate_codes (XEXP (exp, 0), op0_codes);
257 for (i = 0; i < NUM_RTX_CODE; i++)
258 codes[i] = TRISTATE_NOT (op0_codes[i]);
262 /* a ? b : c accepts the same codes as (a & b) | (!a & c). */
263 compute_predicate_codes (XEXP (exp, 0), op0_codes);
264 compute_predicate_codes (XEXP (exp, 1), op1_codes);
265 compute_predicate_codes (XEXP (exp, 2), op2_codes);
266 for (i = 0; i < NUM_RTX_CODE; i++)
267 codes[i] = TRISTATE_OR (TRISTATE_AND (op0_codes[i], op1_codes[i]),
268 TRISTATE_AND (TRISTATE_NOT (op0_codes[i]),
273 /* MATCH_CODE allows a specified list of codes. However, if it
274 does not apply to the top level of the expression, it does not
275 constrain the set of codes for the top level. */
276 if (XSTR (exp, 1)[0] != '\0')
278 memset (codes, Y, NUM_RTX_CODE);
282 memset (codes, N, NUM_RTX_CODE);
284 const char *next_code = XSTR (exp, 0);
287 if (*next_code == '\0')
289 message_with_line (pattern_lineno, "empty match_code expression");
294 while ((code = scan_comma_elt (&next_code)) != 0)
296 size_t n = next_code - code;
299 for (i = 0; i < NUM_RTX_CODE; i++)
300 if (!strncmp (code, GET_RTX_NAME (i), n)
301 && GET_RTX_NAME (i)[n] == '\0')
309 message_with_line (pattern_lineno, "match_code \"%.*s\" matches nothing",
312 for (i = 0; i < NUM_RTX_CODE; i++)
313 if (!strncasecmp (code, GET_RTX_NAME (i), n)
314 && GET_RTX_NAME (i)[n] == '\0'
315 && !did_you_mean_codes[i])
317 did_you_mean_codes[i] = 1;
318 message_with_line (pattern_lineno, "(did you mean \"%s\"?)", GET_RTX_NAME (i));
327 /* MATCH_OPERAND disallows the set of codes that the named predicate
328 disallows, and is indeterminate for the codes that it does allow. */
330 struct pred_data *p = lookup_predicate (XSTR (exp, 1));
333 message_with_line (pattern_lineno,
334 "reference to unknown predicate '%s'",
339 for (i = 0; i < NUM_RTX_CODE; i++)
340 codes[i] = p->codes[i] ? I : N;
346 /* (match_test WHATEVER) is completely indeterminate. */
347 memset (codes, I, NUM_RTX_CODE);
351 message_with_line (pattern_lineno,
352 "'%s' cannot be used in a define_predicate expression",
353 GET_RTX_NAME (GET_CODE (exp)));
355 memset (codes, I, NUM_RTX_CODE);
364 /* Process a define_predicate expression: compute the set of predicates
365 that can be matched, and record this as a known predicate. */
367 process_define_predicate (rtx desc)
369 struct pred_data *pred = XCNEW (struct pred_data);
370 char codes[NUM_RTX_CODE];
373 pred->name = XSTR (desc, 0);
374 if (GET_CODE (desc) == DEFINE_SPECIAL_PREDICATE)
377 compute_predicate_codes (XEXP (desc, 1), codes);
379 for (i = 0; i < NUM_RTX_CODE; i++)
381 add_predicate_code (pred, (enum rtx_code) i);
383 add_predicate (pred);
390 static struct decision *new_decision
391 (const char *, struct decision_head *);
392 static struct decision_test *new_decision_test
393 (enum decision_type, struct decision_test ***);
394 static rtx find_operand
396 static rtx find_matching_operand
398 static void validate_pattern
399 (rtx, rtx, rtx, int);
400 static struct decision *add_to_sequence
401 (rtx, struct decision_head *, const char *, enum routine_type, int);
403 static int maybe_both_true_2
404 (struct decision_test *, struct decision_test *);
405 static int maybe_both_true_1
406 (struct decision_test *, struct decision_test *);
407 static int maybe_both_true
408 (struct decision *, struct decision *, int);
410 static int nodes_identical_1
411 (struct decision_test *, struct decision_test *);
412 static int nodes_identical
413 (struct decision *, struct decision *);
414 static void merge_accept_insn
415 (struct decision *, struct decision *);
416 static void merge_trees
417 (struct decision_head *, struct decision_head *);
419 static void factor_tests
420 (struct decision_head *);
421 static void simplify_tests
422 (struct decision_head *);
423 static int break_out_subroutines
424 (struct decision_head *, int);
425 static void find_afterward
426 (struct decision_head *, struct decision *);
428 static void change_state
429 (const char *, const char *, const char *);
430 static void print_code
432 static void write_afterward
433 (struct decision *, struct decision *, const char *);
434 static struct decision *write_switch
435 (struct decision *, int);
436 static void write_cond
437 (struct decision_test *, int, enum routine_type);
438 static void write_action
439 (struct decision *, struct decision_test *, int, int,
440 struct decision *, enum routine_type);
441 static int is_unconditional
442 (struct decision_test *, enum routine_type);
443 static int write_node
444 (struct decision *, int, enum routine_type);
445 static void write_tree_1
446 (struct decision_head *, int, enum routine_type);
447 static void write_tree
448 (struct decision_head *, const char *, enum routine_type, int);
449 static void write_subroutine
450 (struct decision_head *, enum routine_type);
451 static void write_subroutines
452 (struct decision_head *, enum routine_type);
453 static void write_header
456 static struct decision_head make_insn_sequence
457 (rtx, enum routine_type);
458 static void process_tree
459 (struct decision_head *, enum routine_type);
461 static void debug_decision_0
462 (struct decision *, int, int);
463 static void debug_decision_1
464 (struct decision *, int);
465 static void debug_decision_2
466 (struct decision_test *);
467 extern void debug_decision
469 extern void debug_decision_list
472 /* Create a new node in sequence after LAST. */
474 static struct decision *
475 new_decision (const char *position, struct decision_head *last)
477 struct decision *new_decision = XCNEW (struct decision);
479 new_decision->success = *last;
480 new_decision->position = xstrdup (position);
481 new_decision->number = next_number++;
483 last->first = last->last = new_decision;
487 /* Create a new test and link it in at PLACE. */
489 static struct decision_test *
490 new_decision_test (enum decision_type type, struct decision_test ***pplace)
492 struct decision_test **place = *pplace;
493 struct decision_test *test;
495 test = XNEW (struct decision_test);
506 /* Search for and return operand N, stop when reaching node STOP. */
509 find_operand (rtx pattern, int n, rtx stop)
519 code = GET_CODE (pattern);
520 if ((code == MATCH_SCRATCH
521 || code == MATCH_OPERAND
522 || code == MATCH_OPERATOR
523 || code == MATCH_PARALLEL)
524 && XINT (pattern, 0) == n)
527 fmt = GET_RTX_FORMAT (code);
528 len = GET_RTX_LENGTH (code);
529 for (i = 0; i < len; i++)
534 if ((r = find_operand (XEXP (pattern, i), n, stop)) != NULL_RTX)
539 if (! XVEC (pattern, i))
544 for (j = 0; j < XVECLEN (pattern, i); j++)
545 if ((r = find_operand (XVECEXP (pattern, i, j), n, stop))
550 case 'i': case 'w': case '0': case 's':
561 /* Search for and return operand M, such that it has a matching
562 constraint for operand N. */
565 find_matching_operand (rtx pattern, int n)
572 code = GET_CODE (pattern);
573 if (code == MATCH_OPERAND
574 && (XSTR (pattern, 2)[0] == '0' + n
575 || (XSTR (pattern, 2)[0] == '%'
576 && XSTR (pattern, 2)[1] == '0' + n)))
579 fmt = GET_RTX_FORMAT (code);
580 len = GET_RTX_LENGTH (code);
581 for (i = 0; i < len; i++)
586 if ((r = find_matching_operand (XEXP (pattern, i), n)))
591 if (! XVEC (pattern, i))
596 for (j = 0; j < XVECLEN (pattern, i); j++)
597 if ((r = find_matching_operand (XVECEXP (pattern, i, j), n)))
601 case 'i': case 'w': case '0': case 's':
613 /* Check for various errors in patterns. SET is nonnull for a destination,
614 and is the complete set pattern. SET_CODE is '=' for normal sets, and
615 '+' within a context that requires in-out constraints. */
618 validate_pattern (rtx pattern, rtx insn, rtx set, int set_code)
625 code = GET_CODE (pattern);
633 if (find_operand (insn, XINT (pattern, 0), pattern) == pattern)
635 message_with_line (pattern_lineno,
636 "operand %i duplicated before defined",
644 const char *pred_name = XSTR (pattern, 1);
645 const struct pred_data *pred;
648 if (GET_CODE (insn) == DEFINE_INSN)
649 c_test = XSTR (insn, 2);
651 c_test = XSTR (insn, 1);
653 if (pred_name[0] != 0)
655 pred = lookup_predicate (pred_name);
657 message_with_line (pattern_lineno,
658 "warning: unknown predicate '%s'",
664 if (code == MATCH_OPERAND)
666 const char constraints0 = XSTR (pattern, 2)[0];
668 /* In DEFINE_EXPAND, DEFINE_SPLIT, and DEFINE_PEEPHOLE2, we
669 don't use the MATCH_OPERAND constraint, only the predicate.
670 This is confusing to folks doing new ports, so help them
671 not make the mistake. */
672 if (GET_CODE (insn) == DEFINE_EXPAND
673 || GET_CODE (insn) == DEFINE_SPLIT
674 || GET_CODE (insn) == DEFINE_PEEPHOLE2)
677 message_with_line (pattern_lineno,
678 "warning: constraints not supported in %s",
679 rtx_name[GET_CODE (insn)]);
682 /* A MATCH_OPERAND that is a SET should have an output reload. */
683 else if (set && constraints0)
687 if (constraints0 == '+')
689 /* If we've only got an output reload for this operand,
690 we'd better have a matching input operand. */
691 else if (constraints0 == '='
692 && find_matching_operand (insn, XINT (pattern, 0)))
696 message_with_line (pattern_lineno,
697 "operand %d missing in-out reload",
702 else if (constraints0 != '=' && constraints0 != '+')
704 message_with_line (pattern_lineno,
705 "operand %d missing output reload",
712 /* Allowing non-lvalues in destinations -- particularly CONST_INT --
713 while not likely to occur at runtime, results in less efficient
714 code from insn-recog.c. */
715 if (set && pred && pred->allows_non_lvalue)
716 message_with_line (pattern_lineno,
717 "warning: destination operand %d "
721 /* A modeless MATCH_OPERAND can be handy when we can check for
722 multiple modes in the c_test. In most other cases, it is a
723 mistake. Only DEFINE_INSN is eligible, since SPLIT and
724 PEEP2 can FAIL within the output pattern. Exclude special
725 predicates, which check the mode themselves. Also exclude
726 predicates that allow only constants. Exclude the SET_DEST
727 of a call instruction, as that is a common idiom. */
729 if (GET_MODE (pattern) == VOIDmode
730 && code == MATCH_OPERAND
731 && GET_CODE (insn) == DEFINE_INSN
734 && pred->allows_non_const
735 && strstr (c_test, "operands") == NULL
737 && GET_CODE (set) == SET
738 && GET_CODE (SET_SRC (set)) == CALL))
739 message_with_line (pattern_lineno,
740 "warning: operand %d missing mode?",
747 enum machine_mode dmode, smode;
750 dest = SET_DEST (pattern);
751 src = SET_SRC (pattern);
753 /* STRICT_LOW_PART is a wrapper. Its argument is the real
754 destination, and it's mode should match the source. */
755 if (GET_CODE (dest) == STRICT_LOW_PART)
756 dest = XEXP (dest, 0);
758 /* Find the referent for a DUP. */
760 if (GET_CODE (dest) == MATCH_DUP
761 || GET_CODE (dest) == MATCH_OP_DUP
762 || GET_CODE (dest) == MATCH_PAR_DUP)
763 dest = find_operand (insn, XINT (dest, 0), NULL);
765 if (GET_CODE (src) == MATCH_DUP
766 || GET_CODE (src) == MATCH_OP_DUP
767 || GET_CODE (src) == MATCH_PAR_DUP)
768 src = find_operand (insn, XINT (src, 0), NULL);
770 dmode = GET_MODE (dest);
771 smode = GET_MODE (src);
773 /* The mode of an ADDRESS_OPERAND is the mode of the memory
774 reference, not the mode of the address. */
775 if (GET_CODE (src) == MATCH_OPERAND
776 && ! strcmp (XSTR (src, 1), "address_operand"))
779 /* The operands of a SET must have the same mode unless one
781 else if (dmode != VOIDmode && smode != VOIDmode && dmode != smode)
783 message_with_line (pattern_lineno,
784 "mode mismatch in set: %smode vs %smode",
785 GET_MODE_NAME (dmode), GET_MODE_NAME (smode));
789 /* If only one of the operands is VOIDmode, and PC or CC0 is
790 not involved, it's probably a mistake. */
791 else if (dmode != smode
792 && GET_CODE (dest) != PC
793 && GET_CODE (dest) != CC0
794 && GET_CODE (src) != PC
795 && GET_CODE (src) != CC0
796 && GET_CODE (src) != CONST_INT)
799 which = (dmode == VOIDmode ? "destination" : "source");
800 message_with_line (pattern_lineno,
801 "warning: %s missing a mode?", which);
804 if (dest != SET_DEST (pattern))
805 validate_pattern (dest, insn, pattern, '=');
806 validate_pattern (SET_DEST (pattern), insn, pattern, '=');
807 validate_pattern (SET_SRC (pattern), insn, NULL_RTX, 0);
812 validate_pattern (SET_DEST (pattern), insn, pattern, '=');
816 validate_pattern (XEXP (pattern, 0), insn, set, set ? '+' : 0);
817 validate_pattern (XEXP (pattern, 1), insn, NULL_RTX, 0);
818 validate_pattern (XEXP (pattern, 2), insn, NULL_RTX, 0);
821 case STRICT_LOW_PART:
822 validate_pattern (XEXP (pattern, 0), insn, set, set ? '+' : 0);
826 if (GET_MODE (XEXP (pattern, 0)) != VOIDmode)
828 message_with_line (pattern_lineno,
829 "operand to label_ref %smode not VOIDmode",
830 GET_MODE_NAME (GET_MODE (XEXP (pattern, 0))));
839 fmt = GET_RTX_FORMAT (code);
840 len = GET_RTX_LENGTH (code);
841 for (i = 0; i < len; i++)
846 validate_pattern (XEXP (pattern, i), insn, NULL_RTX, 0);
850 for (j = 0; j < XVECLEN (pattern, i); j++)
851 validate_pattern (XVECEXP (pattern, i, j), insn, NULL_RTX, 0);
854 case 'i': case 'w': case '0': case 's':
863 /* Create a chain of nodes to verify that an rtl expression matches
866 LAST is a pointer to the listhead in the previous node in the chain (or
867 in the calling function, for the first node).
869 POSITION is the string representing the current position in the insn.
871 INSN_TYPE is the type of insn for which we are emitting code.
873 A pointer to the final node in the chain is returned. */
875 static struct decision *
876 add_to_sequence (rtx pattern, struct decision_head *last, const char *position,
877 enum routine_type insn_type, int top)
880 struct decision *this_decision, *sub;
881 struct decision_test *test;
882 struct decision_test **place;
886 int depth = strlen (position);
888 enum machine_mode mode;
890 if (depth > max_depth)
893 subpos = XNEWVAR (char, depth + 2);
894 strcpy (subpos, position);
895 subpos[depth + 1] = 0;
897 sub = this_decision = new_decision (position, last);
898 place = &this_decision->tests;
901 mode = GET_MODE (pattern);
902 code = GET_CODE (pattern);
907 /* Toplevel peephole pattern. */
908 if (insn_type == PEEPHOLE2 && top)
912 /* Check we have sufficient insns. This avoids complications
913 because we then know peep2_next_insn never fails. */
914 num_insns = XVECLEN (pattern, 0);
917 test = new_decision_test (DT_num_insns, &place);
918 test->u.num_insns = num_insns;
919 last = &sub->success;
923 /* We don't need the node we just created -- unlink it. */
924 last->first = last->last = NULL;
927 for (i = 0; i < (size_t) XVECLEN (pattern, 0); i++)
929 /* Which insn we're looking at is represented by A-Z. We don't
930 ever use 'A', however; it is always implied. */
932 subpos[depth] = (i > 0 ? 'A' + i : 0);
933 sub = add_to_sequence (XVECEXP (pattern, 0, i),
934 last, subpos, insn_type, 0);
935 last = &sub->success;
940 /* Else nothing special. */
944 /* The explicit patterns within a match_parallel enforce a minimum
945 length on the vector. The match_parallel predicate may allow
946 for more elements. We do need to check for this minimum here
947 or the code generated to match the internals may reference data
948 beyond the end of the vector. */
949 test = new_decision_test (DT_veclen_ge, &place);
950 test->u.veclen = XVECLEN (pattern, 2);
957 RTX_CODE was_code = code;
958 const char *pred_name;
959 bool allows_const_int = true;
961 if (code == MATCH_SCRATCH)
963 pred_name = "scratch_operand";
968 pred_name = XSTR (pattern, 1);
969 if (code == MATCH_PARALLEL)
975 if (pred_name[0] != 0)
977 const struct pred_data *pred;
979 test = new_decision_test (DT_pred, &place);
980 test->u.pred.name = pred_name;
981 test->u.pred.mode = mode;
983 /* See if we know about this predicate.
984 If we do, remember it for use below.
986 We can optimize the generated code a little if either
987 (a) the predicate only accepts one code, or (b) the
988 predicate does not allow CONST_INT, in which case it
989 can match only if the modes match. */
990 pred = lookup_predicate (pred_name);
993 test->u.pred.data = pred;
994 allows_const_int = pred->codes[CONST_INT];
995 if (was_code == MATCH_PARALLEL
996 && pred->singleton != PARALLEL)
997 message_with_line (pattern_lineno,
998 "predicate '%s' used in match_parallel "
999 "does not allow only PARALLEL", pred->name);
1001 code = pred->singleton;
1004 message_with_line (pattern_lineno,
1005 "warning: unknown predicate '%s' in '%s' expression",
1006 pred_name, GET_RTX_NAME (was_code));
1009 /* Can't enforce a mode if we allow const_int. */
1010 if (allows_const_int)
1013 /* Accept the operand, i.e. record it in `operands'. */
1014 test = new_decision_test (DT_accept_op, &place);
1015 test->u.opno = XINT (pattern, 0);
1017 if (was_code == MATCH_OPERATOR || was_code == MATCH_PARALLEL)
1019 char base = (was_code == MATCH_OPERATOR ? '0' : 'a');
1020 for (i = 0; i < (size_t) XVECLEN (pattern, 2); i++)
1022 subpos[depth] = i + base;
1023 sub = add_to_sequence (XVECEXP (pattern, 2, i),
1024 &sub->success, subpos, insn_type, 0);
1033 test = new_decision_test (DT_dup, &place);
1034 test->u.dup = XINT (pattern, 0);
1036 test = new_decision_test (DT_accept_op, &place);
1037 test->u.opno = XINT (pattern, 0);
1039 for (i = 0; i < (size_t) XVECLEN (pattern, 1); i++)
1041 subpos[depth] = i + '0';
1042 sub = add_to_sequence (XVECEXP (pattern, 1, i),
1043 &sub->success, subpos, insn_type, 0);
1051 test = new_decision_test (DT_dup, &place);
1052 test->u.dup = XINT (pattern, 0);
1056 pattern = XEXP (pattern, 0);
1063 fmt = GET_RTX_FORMAT (code);
1064 len = GET_RTX_LENGTH (code);
1066 /* Do tests against the current node first. */
1067 for (i = 0; i < (size_t) len; i++)
1075 test = new_decision_test (DT_elt_zero_int, &place);
1076 test->u.intval = XINT (pattern, i);
1080 test = new_decision_test (DT_elt_one_int, &place);
1081 test->u.intval = XINT (pattern, i);
1084 else if (fmt[i] == 'w')
1086 /* If this value actually fits in an int, we can use a switch
1087 statement here, so indicate that. */
1088 enum decision_type type
1089 = ((int) XWINT (pattern, i) == XWINT (pattern, i))
1090 ? DT_elt_zero_wide_safe : DT_elt_zero_wide;
1094 test = new_decision_test (type, &place);
1095 test->u.intval = XWINT (pattern, i);
1097 else if (fmt[i] == 'E')
1101 test = new_decision_test (DT_veclen, &place);
1102 test->u.veclen = XVECLEN (pattern, i);
1106 /* Now test our sub-patterns. */
1107 for (i = 0; i < (size_t) len; i++)
1112 subpos[depth] = '0' + i;
1113 sub = add_to_sequence (XEXP (pattern, i), &sub->success,
1114 subpos, insn_type, 0);
1120 for (j = 0; j < XVECLEN (pattern, i); j++)
1122 subpos[depth] = 'a' + j;
1123 sub = add_to_sequence (XVECEXP (pattern, i, j),
1124 &sub->success, subpos, insn_type, 0);
1130 /* Handled above. */
1141 /* Insert nodes testing mode and code, if they're still relevant,
1142 before any of the nodes we may have added above. */
1143 if (code != UNKNOWN)
1145 place = &this_decision->tests;
1146 test = new_decision_test (DT_code, &place);
1147 test->u.code = code;
1150 if (mode != VOIDmode)
1152 place = &this_decision->tests;
1153 test = new_decision_test (DT_mode, &place);
1154 test->u.mode = mode;
1157 /* If we didn't insert any tests or accept nodes, hork. */
1158 gcc_assert (this_decision->tests);
1165 /* A subroutine of maybe_both_true; examines only one test.
1166 Returns > 0 for "definitely both true" and < 0 for "maybe both true". */
1169 maybe_both_true_2 (struct decision_test *d1, struct decision_test *d2)
1171 if (d1->type == d2->type)
1176 if (d1->u.num_insns == d2->u.num_insns)
1182 return d1->u.mode == d2->u.mode;
1185 return d1->u.code == d2->u.code;
1188 return d1->u.veclen == d2->u.veclen;
1190 case DT_elt_zero_int:
1191 case DT_elt_one_int:
1192 case DT_elt_zero_wide:
1193 case DT_elt_zero_wide_safe:
1194 return d1->u.intval == d2->u.intval;
1201 /* If either has a predicate that we know something about, set
1202 things up so that D1 is the one that always has a known
1203 predicate. Then see if they have any codes in common. */
1205 if (d1->type == DT_pred || d2->type == DT_pred)
1207 if (d2->type == DT_pred)
1209 struct decision_test *tmp;
1210 tmp = d1, d1 = d2, d2 = tmp;
1213 /* If D2 tests a mode, see if it matches D1. */
1214 if (d1->u.pred.mode != VOIDmode)
1216 if (d2->type == DT_mode)
1218 if (d1->u.pred.mode != d2->u.mode
1219 /* The mode of an address_operand predicate is the
1220 mode of the memory, not the operand. It can only
1221 be used for testing the predicate, so we must
1223 && strcmp (d1->u.pred.name, "address_operand") != 0)
1226 /* Don't check two predicate modes here, because if both predicates
1227 accept CONST_INT, then both can still be true even if the modes
1228 are different. If they don't accept CONST_INT, there will be a
1229 separate DT_mode that will make maybe_both_true_1 return 0. */
1232 if (d1->u.pred.data)
1234 /* If D2 tests a code, see if it is in the list of valid
1235 codes for D1's predicate. */
1236 if (d2->type == DT_code)
1238 if (!d1->u.pred.data->codes[d2->u.code])
1242 /* Otherwise see if the predicates have any codes in common. */
1243 else if (d2->type == DT_pred && d2->u.pred.data)
1245 bool common = false;
1248 for (c = 0; c < NUM_RTX_CODE; c++)
1249 if (d1->u.pred.data->codes[c] && d2->u.pred.data->codes[c])
1261 /* Tests vs veclen may be known when strict equality is involved. */
1262 if (d1->type == DT_veclen && d2->type == DT_veclen_ge)
1263 return d1->u.veclen >= d2->u.veclen;
1264 if (d1->type == DT_veclen_ge && d2->type == DT_veclen)
1265 return d2->u.veclen >= d1->u.veclen;
1270 /* A subroutine of maybe_both_true; examines all the tests for a given node.
1271 Returns > 0 for "definitely both true" and < 0 for "maybe both true". */
1274 maybe_both_true_1 (struct decision_test *d1, struct decision_test *d2)
1276 struct decision_test *t1, *t2;
1278 /* A match_operand with no predicate can match anything. Recognize
1279 this by the existence of a lone DT_accept_op test. */
1280 if (d1->type == DT_accept_op || d2->type == DT_accept_op)
1283 /* Eliminate pairs of tests while they can exactly match. */
1284 while (d1 && d2 && d1->type == d2->type)
1286 if (maybe_both_true_2 (d1, d2) == 0)
1288 d1 = d1->next, d2 = d2->next;
1291 /* After that, consider all pairs. */
1292 for (t1 = d1; t1 ; t1 = t1->next)
1293 for (t2 = d2; t2 ; t2 = t2->next)
1294 if (maybe_both_true_2 (t1, t2) == 0)
1300 /* Return 0 if we can prove that there is no RTL that can match both
1301 D1 and D2. Otherwise, return 1 (it may be that there is an RTL that
1302 can match both or just that we couldn't prove there wasn't such an RTL).
1304 TOPLEVEL is nonzero if we are to only look at the top level and not
1305 recursively descend. */
1308 maybe_both_true (struct decision *d1, struct decision *d2,
1311 struct decision *p1, *p2;
1314 /* Don't compare strings on the different positions in insn. Doing so
1315 is incorrect and results in false matches from constructs like
1317 [(set (subreg:HI (match_operand:SI "register_operand" "r") 0)
1318 (subreg:HI (match_operand:SI "register_operand" "r") 0))]
1320 [(set (match_operand:HI "register_operand" "r")
1321 (match_operand:HI "register_operand" "r"))]
1323 If we are presented with such, we are recursing through the remainder
1324 of a node's success nodes (from the loop at the end of this function).
1325 Skip forward until we come to a position that matches.
1327 Due to the way position strings are constructed, we know that iterating
1328 forward from the lexically lower position (e.g. "00") will run into
1329 the lexically higher position (e.g. "1") and not the other way around.
1330 This saves a bit of effort. */
1332 cmp = strcmp (d1->position, d2->position);
1335 gcc_assert (!toplevel);
1337 /* If the d2->position was lexically lower, swap. */
1339 p1 = d1, d1 = d2, d2 = p1;
1341 if (d1->success.first == 0)
1343 for (p1 = d1->success.first; p1; p1 = p1->next)
1344 if (maybe_both_true (p1, d2, 0))
1350 /* Test the current level. */
1351 cmp = maybe_both_true_1 (d1->tests, d2->tests);
1355 /* We can't prove that D1 and D2 cannot both be true. If we are only
1356 to check the top level, return 1. Otherwise, see if we can prove
1357 that all choices in both successors are mutually exclusive. If
1358 either does not have any successors, we can't prove they can't both
1361 if (toplevel || d1->success.first == 0 || d2->success.first == 0)
1364 for (p1 = d1->success.first; p1; p1 = p1->next)
1365 for (p2 = d2->success.first; p2; p2 = p2->next)
1366 if (maybe_both_true (p1, p2, 0))
1372 /* A subroutine of nodes_identical. Examine two tests for equivalence. */
1375 nodes_identical_1 (struct decision_test *d1, struct decision_test *d2)
1380 return d1->u.num_insns == d2->u.num_insns;
1383 return d1->u.mode == d2->u.mode;
1386 return d1->u.code == d2->u.code;
1389 return (d1->u.pred.mode == d2->u.pred.mode
1390 && strcmp (d1->u.pred.name, d2->u.pred.name) == 0);
1393 return strcmp (d1->u.c_test, d2->u.c_test) == 0;
1397 return d1->u.veclen == d2->u.veclen;
1400 return d1->u.dup == d2->u.dup;
1402 case DT_elt_zero_int:
1403 case DT_elt_one_int:
1404 case DT_elt_zero_wide:
1405 case DT_elt_zero_wide_safe:
1406 return d1->u.intval == d2->u.intval;
1409 return d1->u.opno == d2->u.opno;
1411 case DT_accept_insn:
1412 /* Differences will be handled in merge_accept_insn. */
1420 /* True iff the two nodes are identical (on one level only). Due
1421 to the way these lists are constructed, we shouldn't have to
1422 consider different orderings on the tests. */
1425 nodes_identical (struct decision *d1, struct decision *d2)
1427 struct decision_test *t1, *t2;
1429 for (t1 = d1->tests, t2 = d2->tests; t1 && t2; t1 = t1->next, t2 = t2->next)
1431 if (t1->type != t2->type)
1433 if (! nodes_identical_1 (t1, t2))
1437 /* For success, they should now both be null. */
1441 /* Check that their subnodes are at the same position, as any one set
1442 of sibling decisions must be at the same position. Allowing this
1443 requires complications to find_afterward and when change_state is
1445 if (d1->success.first
1446 && d2->success.first
1447 && strcmp (d1->success.first->position, d2->success.first->position))
1453 /* A subroutine of merge_trees; given two nodes that have been declared
1454 identical, cope with two insn accept states. If they differ in the
1455 number of clobbers, then the conflict was created by make_insn_sequence
1456 and we can drop the with-clobbers version on the floor. If both
1457 nodes have no additional clobbers, we have found an ambiguity in the
1458 source machine description. */
1461 merge_accept_insn (struct decision *oldd, struct decision *addd)
1463 struct decision_test *old, *add;
1465 for (old = oldd->tests; old; old = old->next)
1466 if (old->type == DT_accept_insn)
1471 for (add = addd->tests; add; add = add->next)
1472 if (add->type == DT_accept_insn)
1477 /* If one node is for a normal insn and the second is for the base
1478 insn with clobbers stripped off, the second node should be ignored. */
1480 if (old->u.insn.num_clobbers_to_add == 0
1481 && add->u.insn.num_clobbers_to_add > 0)
1483 /* Nothing to do here. */
1485 else if (old->u.insn.num_clobbers_to_add > 0
1486 && add->u.insn.num_clobbers_to_add == 0)
1488 /* In this case, replace OLD with ADD. */
1489 old->u.insn = add->u.insn;
1493 message_with_line (add->u.insn.lineno, "`%s' matches `%s'",
1494 get_insn_name (add->u.insn.code_number),
1495 get_insn_name (old->u.insn.code_number));
1496 message_with_line (old->u.insn.lineno, "previous definition of `%s'",
1497 get_insn_name (old->u.insn.code_number));
1502 /* Merge two decision trees OLDH and ADDH, modifying OLDH destructively. */
1505 merge_trees (struct decision_head *oldh, struct decision_head *addh)
1507 struct decision *next, *add;
1509 if (addh->first == 0)
1511 if (oldh->first == 0)
1517 /* Trying to merge bits at different positions isn't possible. */
1518 gcc_assert (!strcmp (oldh->first->position, addh->first->position));
1520 for (add = addh->first; add ; add = next)
1522 struct decision *old, *insert_before = NULL;
1526 /* The semantics of pattern matching state that the tests are
1527 done in the order given in the MD file so that if an insn
1528 matches two patterns, the first one will be used. However,
1529 in practice, most, if not all, patterns are unambiguous so
1530 that their order is independent. In that case, we can merge
1531 identical tests and group all similar modes and codes together.
1533 Scan starting from the end of OLDH until we reach a point
1534 where we reach the head of the list or where we pass a
1535 pattern that could also be true if NEW is true. If we find
1536 an identical pattern, we can merge them. Also, record the
1537 last node that tests the same code and mode and the last one
1538 that tests just the same mode.
1540 If we have no match, place NEW after the closest match we found. */
1542 for (old = oldh->last; old; old = old->prev)
1544 if (nodes_identical (old, add))
1546 merge_accept_insn (old, add);
1547 merge_trees (&old->success, &add->success);
1551 if (maybe_both_true (old, add, 0))
1554 /* Insert the nodes in DT test type order, which is roughly
1555 how expensive/important the test is. Given that the tests
1556 are also ordered within the list, examining the first is
1558 if ((int) add->tests->type < (int) old->tests->type)
1559 insert_before = old;
1562 if (insert_before == NULL)
1565 add->prev = oldh->last;
1566 oldh->last->next = add;
1571 if ((add->prev = insert_before->prev) != NULL)
1572 add->prev->next = add;
1575 add->next = insert_before;
1576 insert_before->prev = add;
1583 /* Walk the tree looking for sub-nodes that perform common tests.
1584 Factor out the common test into a new node. This enables us
1585 (depending on the test type) to emit switch statements later. */
1588 factor_tests (struct decision_head *head)
1590 struct decision *first, *next;
1592 for (first = head->first; first && first->next; first = next)
1594 enum decision_type type;
1595 struct decision *new_dec, *old_last;
1597 type = first->tests->type;
1600 /* Want at least two compatible sequential nodes. */
1601 if (next->tests->type != type)
1604 /* Don't want all node types, just those we can turn into
1605 switch statements. */
1608 && type != DT_veclen
1609 && type != DT_elt_zero_int
1610 && type != DT_elt_one_int
1611 && type != DT_elt_zero_wide_safe)
1614 /* If we'd been performing more than one test, create a new node
1615 below our first test. */
1616 if (first->tests->next != NULL)
1618 new_dec = new_decision (first->position, &first->success);
1619 new_dec->tests = first->tests->next;
1620 first->tests->next = NULL;
1623 /* Crop the node tree off after our first test. */
1625 old_last = head->last;
1628 /* For each compatible test, adjust to perform only one test in
1629 the top level node, then merge the node back into the tree. */
1632 struct decision_head h;
1634 if (next->tests->next != NULL)
1636 new_dec = new_decision (next->position, &next->success);
1637 new_dec->tests = next->tests->next;
1638 next->tests->next = NULL;
1642 new_dec->next = NULL;
1643 h.first = h.last = new_dec;
1645 merge_trees (head, &h);
1647 while (next && next->tests->type == type);
1649 /* After we run out of compatible tests, graft the remaining nodes
1650 back onto the tree. */
1653 next->prev = head->last;
1654 head->last->next = next;
1655 head->last = old_last;
1660 for (first = head->first; first; first = first->next)
1661 factor_tests (&first->success);
1664 /* After factoring, try to simplify the tests on any one node.
1665 Tests that are useful for switch statements are recognizable
1666 by having only a single test on a node -- we'll be manipulating
1667 nodes with multiple tests:
1669 If we have mode tests or code tests that are redundant with
1670 predicates, remove them. */
1673 simplify_tests (struct decision_head *head)
1675 struct decision *tree;
1677 for (tree = head->first; tree; tree = tree->next)
1679 struct decision_test *a, *b;
1686 /* Find a predicate node. */
1687 while (b && b->type != DT_pred)
1691 /* Due to how these tests are constructed, we don't even need
1692 to check that the mode and code are compatible -- they were
1693 generated from the predicate in the first place. */
1694 while (a->type == DT_mode || a->type == DT_code)
1701 for (tree = head->first; tree; tree = tree->next)
1702 simplify_tests (&tree->success);
1705 /* Count the number of subnodes of HEAD. If the number is high enough,
1706 make the first node in HEAD start a separate subroutine in the C code
1707 that is generated. */
1710 break_out_subroutines (struct decision_head *head, int initial)
1713 struct decision *sub;
1715 for (sub = head->first; sub; sub = sub->next)
1716 size += 1 + break_out_subroutines (&sub->success, 0);
1718 if (size > SUBROUTINE_THRESHOLD && ! initial)
1720 head->first->subroutine_number = ++next_subroutine_number;
1726 /* For each node p, find the next alternative that might be true
1730 find_afterward (struct decision_head *head, struct decision *real_afterward)
1732 struct decision *p, *q, *afterward;
1734 /* We can't propagate alternatives across subroutine boundaries.
1735 This is not incorrect, merely a minor optimization loss. */
1738 afterward = (p->subroutine_number > 0 ? NULL : real_afterward);
1740 for ( ; p ; p = p->next)
1742 /* Find the next node that might be true if this one fails. */
1743 for (q = p->next; q ; q = q->next)
1744 if (maybe_both_true (p, q, 1))
1747 /* If we reached the end of the list without finding one,
1748 use the incoming afterward position. */
1757 for (p = head->first; p ; p = p->next)
1758 if (p->success.first)
1759 find_afterward (&p->success, p->afterward);
1761 /* When we are generating a subroutine, record the real afterward
1762 position in the first node where write_tree can find it, and we
1763 can do the right thing at the subroutine call site. */
1765 if (p->subroutine_number > 0)
1766 p->afterward = real_afterward;
1769 /* Assuming that the state of argument is denoted by OLDPOS, take whatever
1770 actions are necessary to move to NEWPOS. If we fail to move to the
1771 new state, branch to node AFTERWARD if nonzero, otherwise return.
1773 Failure to move to the new state can only occur if we are trying to
1774 match multiple insns and we try to step past the end of the stream. */
1777 change_state (const char *oldpos, const char *newpos, const char *indent)
1779 int odepth = strlen (oldpos);
1780 int ndepth = strlen (newpos);
1782 int old_has_insn, new_has_insn;
1784 /* Pop up as many levels as necessary. */
1785 for (depth = odepth; strncmp (oldpos, newpos, depth) != 0; --depth)
1788 /* Hunt for the last [A-Z] in both strings. */
1789 for (old_has_insn = odepth - 1; old_has_insn >= 0; --old_has_insn)
1790 if (ISUPPER (oldpos[old_has_insn]))
1792 for (new_has_insn = ndepth - 1; new_has_insn >= 0; --new_has_insn)
1793 if (ISUPPER (newpos[new_has_insn]))
1796 /* Go down to desired level. */
1797 while (depth < ndepth)
1799 /* It's a different insn from the first one. */
1800 if (ISUPPER (newpos[depth]))
1802 printf ("%stem = peep2_next_insn (%d);\n",
1803 indent, newpos[depth] - 'A');
1804 printf ("%sx%d = PATTERN (tem);\n", indent, depth + 1);
1806 else if (ISLOWER (newpos[depth]))
1807 printf ("%sx%d = XVECEXP (x%d, 0, %d);\n",
1808 indent, depth + 1, depth, newpos[depth] - 'a');
1810 printf ("%sx%d = XEXP (x%d, %c);\n",
1811 indent, depth + 1, depth, newpos[depth]);
1816 /* Print the enumerator constant for CODE -- the upcase version of
1820 print_code (enum rtx_code code)
1823 for (p = GET_RTX_NAME (code); *p; p++)
1824 putchar (TOUPPER (*p));
1827 /* Emit code to cross an afterward link -- change state and branch. */
1830 write_afterward (struct decision *start, struct decision *afterward,
1833 if (!afterward || start->subroutine_number > 0)
1834 printf("%sgoto ret0;\n", indent);
1837 change_state (start->position, afterward->position, indent);
1838 printf ("%sgoto L%d;\n", indent, afterward->number);
1842 /* Emit a HOST_WIDE_INT as an integer constant expression. We need to take
1843 special care to avoid "decimal constant is so large that it is unsigned"
1844 warnings in the resulting code. */
1847 print_host_wide_int (HOST_WIDE_INT val)
1849 HOST_WIDE_INT min = (unsigned HOST_WIDE_INT)1 << (HOST_BITS_PER_WIDE_INT-1);
1851 printf ("(" HOST_WIDE_INT_PRINT_DEC_C "-1)", val + 1);
1853 printf (HOST_WIDE_INT_PRINT_DEC_C, val);
1856 /* Emit a switch statement, if possible, for an initial sequence of
1857 nodes at START. Return the first node yet untested. */
1859 static struct decision *
1860 write_switch (struct decision *start, int depth)
1862 struct decision *p = start;
1863 enum decision_type type = p->tests->type;
1864 struct decision *needs_label = NULL;
1866 /* If we have two or more nodes in sequence that test the same one
1867 thing, we may be able to use a switch statement. */
1871 || p->next->tests->type != type
1872 || p->next->tests->next
1873 || nodes_identical_1 (p->tests, p->next->tests))
1876 /* DT_code is special in that we can do interesting things with
1877 known predicates at the same time. */
1878 if (type == DT_code)
1880 char codemap[NUM_RTX_CODE];
1881 struct decision *ret;
1884 memset (codemap, 0, sizeof(codemap));
1886 printf (" switch (GET_CODE (x%d))\n {\n", depth);
1887 code = p->tests->u.code;
1890 if (p != start && p->need_label && needs_label == NULL)
1895 printf (":\n goto L%d;\n", p->success.first->number);
1896 p->success.first->need_label = 1;
1903 && p->tests->type == DT_code
1904 && ! codemap[code = p->tests->u.code]);
1906 /* If P is testing a predicate that we know about and we haven't
1907 seen any of the codes that are valid for the predicate, we can
1908 write a series of "case" statement, one for each possible code.
1909 Since we are already in a switch, these redundant tests are very
1910 cheap and will reduce the number of predicates called. */
1912 /* Note that while we write out cases for these predicates here,
1913 we don't actually write the test here, as it gets kinda messy.
1914 It is trivial to leave this to later by telling our caller that
1915 we only processed the CODE tests. */
1916 if (needs_label != NULL)
1921 while (p && p->tests->type == DT_pred && p->tests->u.pred.data)
1923 const struct pred_data *data = p->tests->u.pred.data;
1926 for (c = 0; c < NUM_RTX_CODE; c++)
1927 if (codemap[c] && data->codes[c])
1930 for (c = 0; c < NUM_RTX_CODE; c++)
1933 fputs (" case ", stdout);
1934 print_code ((enum rtx_code) c);
1935 fputs (":\n", stdout);
1939 printf (" goto L%d;\n", p->number);
1945 /* Make the default case skip the predicates we managed to match. */
1947 printf (" default:\n");
1952 printf (" goto L%d;\n", p->number);
1956 write_afterward (start, start->afterward, " ");
1959 printf (" break;\n");
1964 else if (type == DT_mode
1965 || type == DT_veclen
1966 || type == DT_elt_zero_int
1967 || type == DT_elt_one_int
1968 || type == DT_elt_zero_wide_safe)
1970 const char *indent = "";
1972 /* We cast switch parameter to integer, so we must ensure that the value
1974 if (type == DT_elt_zero_wide_safe)
1977 printf(" if ((int) XWINT (x%d, 0) == XWINT (x%d, 0))\n", depth, depth);
1979 printf ("%s switch (", indent);
1983 printf ("GET_MODE (x%d)", depth);
1986 printf ("XVECLEN (x%d, 0)", depth);
1988 case DT_elt_zero_int:
1989 printf ("XINT (x%d, 0)", depth);
1991 case DT_elt_one_int:
1992 printf ("XINT (x%d, 1)", depth);
1994 case DT_elt_zero_wide_safe:
1995 /* Convert result of XWINT to int for portability since some C
1996 compilers won't do it and some will. */
1997 printf ("(int) XWINT (x%d, 0)", depth);
2002 printf (")\n%s {\n", indent);
2006 /* Merge trees will not unify identical nodes if their
2007 sub-nodes are at different levels. Thus we must check
2008 for duplicate cases. */
2010 for (q = start; q != p; q = q->next)
2011 if (nodes_identical_1 (p->tests, q->tests))
2014 if (p != start && p->need_label && needs_label == NULL)
2017 printf ("%s case ", indent);
2021 printf ("%smode", GET_MODE_NAME (p->tests->u.mode));
2024 printf ("%d", p->tests->u.veclen);
2026 case DT_elt_zero_int:
2027 case DT_elt_one_int:
2028 case DT_elt_zero_wide:
2029 case DT_elt_zero_wide_safe:
2030 print_host_wide_int (p->tests->u.intval);
2035 printf (":\n%s goto L%d;\n", indent, p->success.first->number);
2036 p->success.first->need_label = 1;
2040 while (p && p->tests->type == type && !p->tests->next);
2043 printf ("%s default:\n%s break;\n%s }\n",
2044 indent, indent, indent);
2046 return needs_label != NULL ? needs_label : p;
2050 /* None of the other tests are amenable. */
2055 /* Emit code for one test. */
2058 write_cond (struct decision_test *p, int depth,
2059 enum routine_type subroutine_type)
2064 printf ("peep2_current_count >= %d", p->u.num_insns);
2068 printf ("GET_MODE (x%d) == %smode", depth, GET_MODE_NAME (p->u.mode));
2072 printf ("GET_CODE (x%d) == ", depth);
2073 print_code (p->u.code);
2077 printf ("XVECLEN (x%d, 0) == %d", depth, p->u.veclen);
2080 case DT_elt_zero_int:
2081 printf ("XINT (x%d, 0) == %d", depth, (int) p->u.intval);
2084 case DT_elt_one_int:
2085 printf ("XINT (x%d, 1) == %d", depth, (int) p->u.intval);
2088 case DT_elt_zero_wide:
2089 case DT_elt_zero_wide_safe:
2090 printf ("XWINT (x%d, 0) == ", depth);
2091 print_host_wide_int (p->u.intval);
2095 printf ("x%d == const_int_rtx[MAX_SAVED_CONST_INT + (%d)]",
2096 depth, (int) p->u.intval);
2100 printf ("XVECLEN (x%d, 0) >= %d", depth, p->u.veclen);
2104 printf ("rtx_equal_p (x%d, operands[%d])", depth, p->u.dup);
2108 printf ("%s (x%d, %smode)", p->u.pred.name, depth,
2109 GET_MODE_NAME (p->u.pred.mode));
2113 print_c_condition (p->u.c_test);
2116 case DT_accept_insn:
2117 gcc_assert (subroutine_type == RECOG);
2118 gcc_assert (p->u.insn.num_clobbers_to_add);
2119 printf ("pnum_clobbers != NULL");
2127 /* Emit code for one action. The previous tests have succeeded;
2128 TEST is the last of the chain. In the normal case we simply
2129 perform a state change. For the `accept' tests we must do more work. */
2132 write_action (struct decision *p, struct decision_test *test,
2133 int depth, int uncond, struct decision *success,
2134 enum routine_type subroutine_type)
2141 else if (test->type == DT_accept_op || test->type == DT_accept_insn)
2143 fputs (" {\n", stdout);
2150 if (test->type == DT_accept_op)
2152 printf("%soperands[%d] = x%d;\n", indent, test->u.opno, depth);
2154 /* Only allow DT_accept_insn to follow. */
2158 gcc_assert (test->type == DT_accept_insn);
2162 /* Sanity check that we're now at the end of the list of tests. */
2163 gcc_assert (!test->next);
2165 if (test->type == DT_accept_insn)
2167 switch (subroutine_type)
2170 if (test->u.insn.num_clobbers_to_add != 0)
2171 printf ("%s*pnum_clobbers = %d;\n",
2172 indent, test->u.insn.num_clobbers_to_add);
2173 printf ("%sreturn %d; /* %s */\n", indent,
2174 test->u.insn.code_number,
2175 get_insn_name (test->u.insn.code_number));
2179 printf ("%sreturn gen_split_%d (insn, operands);\n",
2180 indent, test->u.insn.code_number);
2185 int match_len = 0, i;
2187 for (i = strlen (p->position) - 1; i >= 0; --i)
2188 if (ISUPPER (p->position[i]))
2190 match_len = p->position[i] - 'A';
2193 printf ("%s*_pmatch_len = %d;\n", indent, match_len);
2194 printf ("%stem = gen_peephole2_%d (insn, operands);\n",
2195 indent, test->u.insn.code_number);
2196 printf ("%sif (tem != 0)\n%s return tem;\n", indent, indent);
2206 printf("%sgoto L%d;\n", indent, success->number);
2207 success->need_label = 1;
2211 fputs (" }\n", stdout);
2214 /* Return 1 if the test is always true and has no fallthru path. Return -1
2215 if the test does have a fallthru path, but requires that the condition be
2216 terminated. Otherwise return 0 for a normal test. */
2217 /* ??? is_unconditional is a stupid name for a tri-state function. */
2220 is_unconditional (struct decision_test *t, enum routine_type subroutine_type)
2222 if (t->type == DT_accept_op)
2225 if (t->type == DT_accept_insn)
2227 switch (subroutine_type)
2230 return (t->u.insn.num_clobbers_to_add == 0);
2243 /* Emit code for one node -- the conditional and the accompanying action.
2244 Return true if there is no fallthru path. */
2247 write_node (struct decision *p, int depth,
2248 enum routine_type subroutine_type)
2250 struct decision_test *test, *last_test;
2253 /* Scan the tests and simplify comparisons against small
2255 for (test = p->tests; test; test = test->next)
2257 if (test->type == DT_code
2258 && test->u.code == CONST_INT
2260 && test->next->type == DT_elt_zero_wide_safe
2261 && -MAX_SAVED_CONST_INT <= test->next->u.intval
2262 && test->next->u.intval <= MAX_SAVED_CONST_INT)
2264 test->type = DT_const_int;
2265 test->u.intval = test->next->u.intval;
2266 test->next = test->next->next;
2270 last_test = test = p->tests;
2271 uncond = is_unconditional (test, subroutine_type);
2275 write_cond (test, depth, subroutine_type);
2277 while ((test = test->next) != NULL)
2280 if (is_unconditional (test, subroutine_type))
2284 write_cond (test, depth, subroutine_type);
2290 write_action (p, last_test, depth, uncond, p->success.first, subroutine_type);
2295 /* Emit code for all of the sibling nodes of HEAD. */
2298 write_tree_1 (struct decision_head *head, int depth,
2299 enum routine_type subroutine_type)
2301 struct decision *p, *next;
2304 for (p = head->first; p ; p = next)
2306 /* The label for the first element was printed in write_tree. */
2307 if (p != head->first && p->need_label)
2308 OUTPUT_LABEL (" ", p->number);
2310 /* Attempt to write a switch statement for a whole sequence. */
2311 next = write_switch (p, depth);
2316 /* Failed -- fall back and write one node. */
2317 uncond = write_node (p, depth, subroutine_type);
2322 /* Finished with this chain. Close a fallthru path by branching
2323 to the afterward node. */
2325 write_afterward (head->last, head->last->afterward, " ");
2328 /* Write out the decision tree starting at HEAD. PREVPOS is the
2329 position at the node that branched to this node. */
2332 write_tree (struct decision_head *head, const char *prevpos,
2333 enum routine_type type, int initial)
2335 struct decision *p = head->first;
2339 OUTPUT_LABEL (" ", p->number);
2341 if (! initial && p->subroutine_number > 0)
2343 static const char * const name_prefix[] = {
2344 "recog", "split", "peephole2"
2347 static const char * const call_suffix[] = {
2348 ", pnum_clobbers", "", ", _pmatch_len"
2351 /* This node has been broken out into a separate subroutine.
2352 Call it, test the result, and branch accordingly. */
2356 printf (" tem = %s_%d (x0, insn%s);\n",
2357 name_prefix[type], p->subroutine_number, call_suffix[type]);
2358 if (IS_SPLIT (type))
2359 printf (" if (tem != 0)\n return tem;\n");
2361 printf (" if (tem >= 0)\n return tem;\n");
2363 change_state (p->position, p->afterward->position, " ");
2364 printf (" goto L%d;\n", p->afterward->number);
2368 printf (" return %s_%d (x0, insn%s);\n",
2369 name_prefix[type], p->subroutine_number, call_suffix[type]);
2374 int depth = strlen (p->position);
2376 change_state (prevpos, p->position, " ");
2377 write_tree_1 (head, depth, type);
2379 for (p = head->first; p; p = p->next)
2380 if (p->success.first)
2381 write_tree (&p->success, p->position, type, 0);
2385 /* Write out a subroutine of type TYPE to do comparisons starting at
2389 write_subroutine (struct decision_head *head, enum routine_type type)
2391 int subfunction = head->first ? head->first->subroutine_number : 0;
2396 s_or_e = subfunction ? "static " : "";
2399 sprintf (extension, "_%d", subfunction);
2400 else if (type == RECOG)
2401 extension[0] = '\0';
2403 strcpy (extension, "_insns");
2409 recog%s (rtx x0 ATTRIBUTE_UNUSED,\n\trtx insn ATTRIBUTE_UNUSED,\n\tint *pnum_clobbers ATTRIBUTE_UNUSED)\n", s_or_e, extension);
2413 split%s (rtx x0 ATTRIBUTE_UNUSED, rtx insn ATTRIBUTE_UNUSED)\n",
2418 peephole2%s (rtx x0 ATTRIBUTE_UNUSED,\n\trtx insn ATTRIBUTE_UNUSED,\n\tint *_pmatch_len ATTRIBUTE_UNUSED)\n",
2423 printf ("{\n rtx * const operands ATTRIBUTE_UNUSED = &recog_data.operand[0];\n");
2424 for (i = 1; i <= max_depth; i++)
2425 printf (" rtx x%d ATTRIBUTE_UNUSED;\n", i);
2427 printf (" %s tem ATTRIBUTE_UNUSED;\n", IS_SPLIT (type) ? "rtx" : "int");
2430 printf (" recog_data.insn = NULL_RTX;\n");
2433 write_tree (head, "", type, 1);
2435 printf (" goto ret0;\n");
2437 printf (" ret0:\n return %d;\n}\n\n", IS_SPLIT (type) ? 0 : -1);
2440 /* In break_out_subroutines, we discovered the boundaries for the
2441 subroutines, but did not write them out. Do so now. */
2444 write_subroutines (struct decision_head *head, enum routine_type type)
2448 for (p = head->first; p ; p = p->next)
2449 if (p->success.first)
2450 write_subroutines (&p->success, type);
2452 if (head->first->subroutine_number > 0)
2453 write_subroutine (head, type);
2456 /* Begin the output file. */
2462 /* Generated automatically by the program `genrecog' from the target\n\
2463 machine description file. */\n\
2465 #include \"config.h\"\n\
2466 #include \"system.h\"\n\
2467 #include \"coretypes.h\"\n\
2468 #include \"tm.h\"\n\
2469 #include \"rtl.h\"\n\
2470 #include \"tm_p.h\"\n\
2471 #include \"function.h\"\n\
2472 #include \"insn-config.h\"\n\
2473 #include \"recog.h\"\n\
2474 #include \"real.h\"\n\
2475 #include \"output.h\"\n\
2476 #include \"flags.h\"\n\
2477 #include \"hard-reg-set.h\"\n\
2478 #include \"resource.h\"\n\
2479 #include \"toplev.h\"\n\
2480 #include \"reload.h\"\n\
2481 #include \"regs.h\"\n\
2482 #include \"tm-constrs.h\"\n\
2486 /* `recog' contains a decision tree that recognizes whether the rtx\n\
2487 X0 is a valid instruction.\n\
2489 recog returns -1 if the rtx is not valid. If the rtx is valid, recog\n\
2490 returns a nonnegative number which is the insn code number for the\n\
2491 pattern that matched. This is the same as the order in the machine\n\
2492 description of the entry that matched. This number can be used as an\n\
2493 index into `insn_data' and other tables.\n");
2495 The third argument to recog is an optional pointer to an int. If\n\
2496 present, recog will accept a pattern if it matches except for missing\n\
2497 CLOBBER expressions at the end. In that case, the value pointed to by\n\
2498 the optional pointer will be set to the number of CLOBBERs that need\n\
2499 to be added (it should be initialized to zero by the caller). If it");
2501 is set nonzero, the caller should allocate a PARALLEL of the\n\
2502 appropriate size, copy the initial entries, and call add_clobbers\n\
2503 (found in insn-emit.c) to fill in the CLOBBERs.\n\
2507 The function split_insns returns 0 if the rtl could not\n\
2508 be split or the split rtl as an INSN list if it can be.\n\
2510 The function peephole2_insns returns 0 if the rtl could not\n\
2511 be matched. If there was a match, the new rtl is returned in an INSN list,\n\
2512 and LAST_INSN will point to the last recognized insn in the old sequence.\n\
2517 /* Construct and return a sequence of decisions
2518 that will recognize INSN.
2520 TYPE says what type of routine we are recognizing (RECOG or SPLIT). */
2522 static struct decision_head
2523 make_insn_sequence (rtx insn, enum routine_type type)
2526 const char *c_test = XSTR (insn, type == RECOG ? 2 : 1);
2527 int truth = maybe_eval_c_test (c_test);
2528 struct decision *last;
2529 struct decision_test *test, **place;
2530 struct decision_head head;
2533 /* We should never see an insn whose C test is false at compile time. */
2536 c_test_pos[0] = '\0';
2537 if (type == PEEPHOLE2)
2541 /* peephole2 gets special treatment:
2542 - X always gets an outer parallel even if it's only one entry
2543 - we remove all traces of outer-level match_scratch and match_dup
2544 expressions here. */
2545 x = rtx_alloc (PARALLEL);
2546 PUT_MODE (x, VOIDmode);
2547 XVEC (x, 0) = rtvec_alloc (XVECLEN (insn, 0));
2548 for (i = j = 0; i < XVECLEN (insn, 0); i++)
2550 rtx tmp = XVECEXP (insn, 0, i);
2551 if (GET_CODE (tmp) != MATCH_SCRATCH && GET_CODE (tmp) != MATCH_DUP)
2553 XVECEXP (x, 0, j) = tmp;
2559 c_test_pos[0] = 'A' + j - 1;
2560 c_test_pos[1] = '\0';
2562 else if (XVECLEN (insn, type == RECOG) == 1)
2563 x = XVECEXP (insn, type == RECOG, 0);
2566 x = rtx_alloc (PARALLEL);
2567 XVEC (x, 0) = XVEC (insn, type == RECOG);
2568 PUT_MODE (x, VOIDmode);
2571 validate_pattern (x, insn, NULL_RTX, 0);
2573 memset(&head, 0, sizeof(head));
2574 last = add_to_sequence (x, &head, "", type, 1);
2576 /* Find the end of the test chain on the last node. */
2577 for (test = last->tests; test->next; test = test->next)
2579 place = &test->next;
2581 /* Skip the C test if it's known to be true at compile time. */
2584 /* Need a new node if we have another test to add. */
2585 if (test->type == DT_accept_op)
2587 last = new_decision (c_test_pos, &last->success);
2588 place = &last->tests;
2590 test = new_decision_test (DT_c_test, &place);
2591 test->u.c_test = c_test;
2594 test = new_decision_test (DT_accept_insn, &place);
2595 test->u.insn.code_number = next_insn_code;
2596 test->u.insn.lineno = pattern_lineno;
2597 test->u.insn.num_clobbers_to_add = 0;
2602 /* If this is a DEFINE_INSN and X is a PARALLEL, see if it ends
2603 with a group of CLOBBERs of (hard) registers or MATCH_SCRATCHes.
2604 If so, set up to recognize the pattern without these CLOBBERs. */
2606 if (GET_CODE (x) == PARALLEL)
2610 /* Find the last non-clobber in the parallel. */
2611 for (i = XVECLEN (x, 0); i > 0; i--)
2613 rtx y = XVECEXP (x, 0, i - 1);
2614 if (GET_CODE (y) != CLOBBER
2615 || (!REG_P (XEXP (y, 0))
2616 && GET_CODE (XEXP (y, 0)) != MATCH_SCRATCH))
2620 if (i != XVECLEN (x, 0))
2623 struct decision_head clobber_head;
2625 /* Build a similar insn without the clobbers. */
2627 new_rtx = XVECEXP (x, 0, 0);
2632 new_rtx = rtx_alloc (PARALLEL);
2633 XVEC (new_rtx, 0) = rtvec_alloc (i);
2634 for (j = i - 1; j >= 0; j--)
2635 XVECEXP (new_rtx, 0, j) = XVECEXP (x, 0, j);
2639 memset (&clobber_head, 0, sizeof(clobber_head));
2640 last = add_to_sequence (new_rtx, &clobber_head, "", type, 1);
2642 /* Find the end of the test chain on the last node. */
2643 for (test = last->tests; test->next; test = test->next)
2646 /* We definitely have a new test to add -- create a new
2648 place = &test->next;
2649 if (test->type == DT_accept_op)
2651 last = new_decision ("", &last->success);
2652 place = &last->tests;
2655 /* Skip the C test if it's known to be true at compile
2659 test = new_decision_test (DT_c_test, &place);
2660 test->u.c_test = c_test;
2663 test = new_decision_test (DT_accept_insn, &place);
2664 test->u.insn.code_number = next_insn_code;
2665 test->u.insn.lineno = pattern_lineno;
2666 test->u.insn.num_clobbers_to_add = XVECLEN (x, 0) - i;
2668 merge_trees (&head, &clobber_head);
2674 /* Define the subroutine we will call below and emit in genemit. */
2675 printf ("extern rtx gen_split_%d (rtx, rtx *);\n", next_insn_code);
2679 /* Define the subroutine we will call below and emit in genemit. */
2680 printf ("extern rtx gen_peephole2_%d (rtx, rtx *);\n",
2689 process_tree (struct decision_head *head, enum routine_type subroutine_type)
2691 if (head->first == NULL)
2693 /* We can elide peephole2_insns, but not recog or split_insns. */
2694 if (subroutine_type == PEEPHOLE2)
2699 factor_tests (head);
2701 next_subroutine_number = 0;
2702 break_out_subroutines (head, 1);
2703 find_afterward (head, NULL);
2705 /* We run this after find_afterward, because find_afterward needs
2706 the redundant DT_mode tests on predicates to determine whether
2707 two tests can both be true or not. */
2708 simplify_tests(head);
2710 write_subroutines (head, subroutine_type);
2713 write_subroutine (head, subroutine_type);
2716 extern int main (int, char **);
2719 main (int argc, char **argv)
2722 struct decision_head recog_tree, split_tree, peephole2_tree, h;
2724 progname = "genrecog";
2726 memset (&recog_tree, 0, sizeof recog_tree);
2727 memset (&split_tree, 0, sizeof split_tree);
2728 memset (&peephole2_tree, 0, sizeof peephole2_tree);
2730 if (init_md_reader_args (argc, argv) != SUCCESS_EXIT_CODE)
2731 return (FATAL_EXIT_CODE);
2737 /* Read the machine description. */
2741 desc = read_md_rtx (&pattern_lineno, &next_insn_code);
2745 switch (GET_CODE (desc))
2747 case DEFINE_PREDICATE:
2748 case DEFINE_SPECIAL_PREDICATE:
2749 process_define_predicate (desc);
2753 h = make_insn_sequence (desc, RECOG);
2754 merge_trees (&recog_tree, &h);
2758 h = make_insn_sequence (desc, SPLIT);
2759 merge_trees (&split_tree, &h);
2762 case DEFINE_PEEPHOLE2:
2763 h = make_insn_sequence (desc, PEEPHOLE2);
2764 merge_trees (&peephole2_tree, &h);
2771 if (error_count || have_error)
2772 return FATAL_EXIT_CODE;
2776 process_tree (&recog_tree, RECOG);
2777 process_tree (&split_tree, SPLIT);
2778 process_tree (&peephole2_tree, PEEPHOLE2);
2781 return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
2785 debug_decision_2 (struct decision_test *test)
2790 fprintf (stderr, "num_insns=%d", test->u.num_insns);
2793 fprintf (stderr, "mode=%s", GET_MODE_NAME (test->u.mode));
2796 fprintf (stderr, "code=%s", GET_RTX_NAME (test->u.code));
2799 fprintf (stderr, "veclen=%d", test->u.veclen);
2801 case DT_elt_zero_int:
2802 fprintf (stderr, "elt0_i=%d", (int) test->u.intval);
2804 case DT_elt_one_int:
2805 fprintf (stderr, "elt1_i=%d", (int) test->u.intval);
2807 case DT_elt_zero_wide:
2808 fprintf (stderr, "elt0_w=" HOST_WIDE_INT_PRINT_DEC, test->u.intval);
2810 case DT_elt_zero_wide_safe:
2811 fprintf (stderr, "elt0_ws=" HOST_WIDE_INT_PRINT_DEC, test->u.intval);
2814 fprintf (stderr, "veclen>=%d", test->u.veclen);
2817 fprintf (stderr, "dup=%d", test->u.dup);
2820 fprintf (stderr, "pred=(%s,%s)",
2821 test->u.pred.name, GET_MODE_NAME(test->u.pred.mode));
2826 strncpy (sub, test->u.c_test, sizeof(sub));
2827 memcpy (sub+16, "...", 4);
2828 fprintf (stderr, "c_test=\"%s\"", sub);
2832 fprintf (stderr, "A_op=%d", test->u.opno);
2834 case DT_accept_insn:
2835 fprintf (stderr, "A_insn=(%d,%d)",
2836 test->u.insn.code_number, test->u.insn.num_clobbers_to_add);
2845 debug_decision_1 (struct decision *d, int indent)
2848 struct decision_test *test;
2852 for (i = 0; i < indent; ++i)
2854 fputs ("(nil)\n", stderr);
2858 for (i = 0; i < indent; ++i)
2865 debug_decision_2 (test);
2866 while ((test = test->next) != NULL)
2868 fputs (" + ", stderr);
2869 debug_decision_2 (test);
2872 fprintf (stderr, "} %d n %d a %d\n", d->number,
2873 (d->next ? d->next->number : -1),
2874 (d->afterward ? d->afterward->number : -1));
2878 debug_decision_0 (struct decision *d, int indent, int maxdepth)
2887 for (i = 0; i < indent; ++i)
2889 fputs ("(nil)\n", stderr);
2893 debug_decision_1 (d, indent);
2894 for (n = d->success.first; n ; n = n->next)
2895 debug_decision_0 (n, indent + 2, maxdepth - 1);
2899 debug_decision (struct decision *d)
2901 debug_decision_0 (d, 0, 1000000);
2905 debug_decision_list (struct decision *d)
2909 debug_decision_0 (d, 0, 0);