1 /* Symbol table manager for Bison.
2
3 Copyright (C) 1984, 1989, 2000-2002, 2004-2012 Free Software
4 Foundation, Inc.
5
6 This file is part of Bison, the GNU Compiler Compiler.
7
8 This program is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation, either version 3 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20
21 #include <config.h>
22 #include "system.h"
23
24 #include <hash.h>
25
26 #include "complain.h"
27 #include "gram.h"
28 #include "symtab.h"
29
30 /*-------------------------------------------------------------------.
31 | Symbols sorted by tag. Allocated by the first invocation of |
32 | symbols_do, after which no more symbols should be created. |
33 `-------------------------------------------------------------------*/
34
35 static symbol **symbols_sorted = NULL;
36
37 /*------------------------.
38 | Distinguished symbols. |
39 `------------------------*/
40
41 symbol *errtoken = NULL;
42 symbol *undeftoken = NULL;
43 symbol *endtoken = NULL;
44 symbol *accept = NULL;
45 symbol *startsymbol = NULL;
46 location startsymbol_location;
47
48 /*---------------------------------------.
49 | Default %destructor's and %printer's. |
50 `---------------------------------------*/
51
52 static code_props default_tagged_destructor = CODE_PROPS_NONE_INIT;
53 static code_props default_tagless_destructor = CODE_PROPS_NONE_INIT;
54 static code_props default_tagged_printer = CODE_PROPS_NONE_INIT;
55 static code_props default_tagless_printer = CODE_PROPS_NONE_INIT;
56
57 /*---------------------------------.
58 | Create a new symbol, named TAG. |
59 `---------------------------------*/
60
61 static symbol *
symbol_new(uniqstr tag,location loc)62 symbol_new (uniqstr tag, location loc)
63 {
64 symbol *res = xmalloc (sizeof *res);
65
66 uniqstr_assert (tag);
67
68 /* If the tag is not a string (starts with a double quote), check
69 that it is valid for Yacc. */
70 if (tag[0] != '\"' && tag[0] != '\'' && mbschr (tag, '-'))
71 yacc_at (loc, _("POSIX Yacc forbids dashes in symbol names: %s"),
72 tag);
73
74 res->tag = tag;
75 res->location = loc;
76
77 res->type_name = NULL;
78 code_props_none_init (&res->destructor);
79 code_props_none_init (&res->printer);
80
81 res->number = NUMBER_UNDEFINED;
82 res->prec = 0;
83 res->assoc = undef_assoc;
84 res->user_token_number = USER_NUMBER_UNDEFINED;
85
86 res->alias = NULL;
87 res->class = unknown_sym;
88 res->declared = false;
89
90 if (nsyms == SYMBOL_NUMBER_MAXIMUM)
91 fatal (_("too many symbols in input grammar (limit is %d)"),
92 SYMBOL_NUMBER_MAXIMUM);
93 nsyms++;
94 return res;
95 }
96
97 /*----------------------------------------.
98 | Create a new semantic type, named TAG. |
99 `----------------------------------------*/
100
101 static semantic_type *
semantic_type_new(uniqstr tag)102 semantic_type_new (uniqstr tag)
103 {
104 semantic_type *res = xmalloc (sizeof *res);
105
106 uniqstr_assert (tag);
107 res->tag = tag;
108 code_props_none_init (&res->destructor);
109 code_props_none_init (&res->printer);
110
111 return res;
112 }
113
114
115 /*-----------------.
116 | Print a symbol. |
117 `-----------------*/
118
119 #define SYMBOL_ATTR_PRINT(Attr) \
120 if (s->Attr) \
121 fprintf (f, " %s { %s }", #Attr, s->Attr)
122
123 #define SYMBOL_CODE_PRINT(Attr) \
124 if (s->Attr.code) \
125 fprintf (f, " %s { %s }", #Attr, s->Attr.code)
126
127 void
symbol_print(symbol * s,FILE * f)128 symbol_print (symbol *s, FILE *f)
129 {
130 if (s)
131 {
132 fprintf (f, "\"%s\"", s->tag);
133 SYMBOL_ATTR_PRINT (type_name);
134 SYMBOL_CODE_PRINT (destructor);
135 SYMBOL_CODE_PRINT (printer);
136 }
137 else
138 fprintf (f, "<NULL>");
139 }
140
141 #undef SYMBOL_ATTR_PRINT
142 #undef SYMBOL_CODE_PRINT
143
144 /*------------------------------------------------------------------.
145 | Complain that S's WHAT is redeclared at SECOND, and was first set |
146 | at FIRST. |
147 `------------------------------------------------------------------*/
148
149 static void
symbol_redeclaration(symbol * s,const char * what,location first,location second)150 symbol_redeclaration (symbol *s, const char *what, location first,
151 location second)
152 {
153 unsigned i = 0;
154 complain_at_indent (second, &i, _("%s redeclaration for %s"), what, s->tag);
155 i += SUB_INDENT;
156 complain_at_indent (first, &i, _("previous declaration"));
157 }
158
159 static void
semantic_type_redeclaration(semantic_type * s,const char * what,location first,location second)160 semantic_type_redeclaration (semantic_type *s, const char *what, location first,
161 location second)
162 {
163 unsigned i = 0;
164 complain_at_indent (second, &i, _("%s redeclaration for <%s>"), what, s->tag);
165 i += SUB_INDENT;
166 complain_at_indent (first, &i, _("previous declaration"));
167 }
168
169
170
171 /*-----------------------------------------------------------------.
172 | Set the TYPE_NAME associated with SYM. Does nothing if passed 0 |
173 | as TYPE_NAME. |
174 `-----------------------------------------------------------------*/
175
176 void
symbol_type_set(symbol * sym,uniqstr type_name,location loc)177 symbol_type_set (symbol *sym, uniqstr type_name, location loc)
178 {
179 if (type_name)
180 {
181 if (sym->type_name)
182 symbol_redeclaration (sym, "%type", sym->type_location, loc);
183 uniqstr_assert (type_name);
184 sym->type_name = type_name;
185 sym->type_location = loc;
186 }
187 }
188
189 /*-----------------------------------------.
190 | Set the DESTRUCTOR associated with SYM. |
191 `-----------------------------------------*/
192
193 void
symbol_destructor_set(symbol * sym,code_props const * destructor)194 symbol_destructor_set (symbol *sym, code_props const *destructor)
195 {
196 if (sym->destructor.code)
197 symbol_redeclaration (sym, "%destructor", sym->destructor.location,
198 destructor->location);
199 sym->destructor = *destructor;
200 }
201
202 /*------------------------------------------.
203 | Set the DESTRUCTOR associated with TYPE. |
204 `------------------------------------------*/
205
206 void
semantic_type_destructor_set(semantic_type * type,code_props const * destructor)207 semantic_type_destructor_set (semantic_type *type,
208 code_props const *destructor)
209 {
210 if (type->destructor.code)
211 semantic_type_redeclaration (type, "%destructor",
212 type->destructor.location,
213 destructor->location);
214 type->destructor = *destructor;
215 }
216
217 /*---------------------------------------.
218 | Get the computed %destructor for SYM. |
219 `---------------------------------------*/
220
221 code_props const *
symbol_destructor_get(symbol const * sym)222 symbol_destructor_get (symbol const *sym)
223 {
224 /* Per-symbol %destructor. */
225 if (sym->destructor.code)
226 return &sym->destructor;
227
228 /* Per-type %destructor. */
229 if (sym->type_name)
230 {
231 code_props const *destructor =
232 &semantic_type_get (sym->type_name)->destructor;
233 if (destructor->code)
234 return destructor;
235 }
236
237 /* Apply default %destructor's only to user-defined symbols. */
238 if (sym->tag[0] == '$' || sym == errtoken)
239 return &code_props_none;
240
241 if (sym->type_name)
242 return &default_tagged_destructor;
243 return &default_tagless_destructor;
244 }
245
246 /*--------------------------------------.
247 | Set the PRINTER associated with SYM. |
248 `--------------------------------------*/
249
250 void
symbol_printer_set(symbol * sym,code_props const * printer)251 symbol_printer_set (symbol *sym, code_props const *printer)
252 {
253 if (sym->printer.code)
254 symbol_redeclaration (sym, "%printer",
255 sym->printer.location, printer->location);
256 sym->printer = *printer;
257 }
258
259 /*---------------------------------------.
260 | Set the PRINTER associated with TYPE. |
261 `---------------------------------------*/
262
263 void
semantic_type_printer_set(semantic_type * type,code_props const * printer)264 semantic_type_printer_set (semantic_type *type, code_props const *printer)
265 {
266 if (type->printer.code)
267 semantic_type_redeclaration (type, "%printer",
268 type->printer.location, printer->location);
269 type->printer = *printer;
270 }
271
272 /*------------------------------------.
273 | Get the computed %printer for SYM. |
274 `------------------------------------*/
275
276 code_props const *
symbol_printer_get(symbol const * sym)277 symbol_printer_get (symbol const *sym)
278 {
279 /* Per-symbol %printer. */
280 if (sym->printer.code)
281 return &sym->printer;
282
283 /* Per-type %printer. */
284 if (sym->type_name)
285 {
286 code_props const *printer = &semantic_type_get (sym->type_name)->printer;
287 if (printer->code)
288 return printer;
289 }
290
291 /* Apply the default %printer only to user-defined symbols. */
292 if (sym->tag[0] == '$' || sym == errtoken)
293 return &code_props_none;
294
295 if (sym->type_name)
296 return &default_tagged_printer;
297 return &default_tagless_printer;
298 }
299
300 /*-----------------------------------------------------------------.
301 | Set the PRECEDENCE associated with SYM. Does nothing if invoked |
302 | with UNDEF_ASSOC as ASSOC. |
303 `-----------------------------------------------------------------*/
304
305 void
symbol_precedence_set(symbol * sym,int prec,assoc a,location loc)306 symbol_precedence_set (symbol *sym, int prec, assoc a, location loc)
307 {
308 if (a != undef_assoc)
309 {
310 if (sym->prec != 0)
311 symbol_redeclaration (sym, assoc_to_string (a), sym->prec_location,
312 loc);
313 sym->prec = prec;
314 sym->assoc = a;
315 sym->prec_location = loc;
316 }
317
318 /* Only terminals have a precedence. */
319 symbol_class_set (sym, token_sym, loc, false);
320 }
321
322
323 /*------------------------------------.
324 | Set the CLASS associated with SYM. |
325 `------------------------------------*/
326
327 void
symbol_class_set(symbol * sym,symbol_class class,location loc,bool declaring)328 symbol_class_set (symbol *sym, symbol_class class, location loc, bool declaring)
329 {
330 if (sym->class != unknown_sym && sym->class != class)
331 {
332 complain_at (loc, _("symbol %s redefined"), sym->tag);
333 sym->declared = false;
334 }
335
336 if (class == nterm_sym && sym->class != nterm_sym)
337 sym->number = nvars++;
338 else if (class == token_sym && sym->number == NUMBER_UNDEFINED)
339 sym->number = ntokens++;
340
341 sym->class = class;
342
343 if (declaring)
344 {
345 if (sym->declared)
346 warn_at (loc, _("symbol %s redeclared"), sym->tag);
347 sym->declared = true;
348 }
349 }
350
351
352 /*------------------------------------------------.
353 | Set the USER_TOKEN_NUMBER associated with SYM. |
354 `------------------------------------------------*/
355
356 void
symbol_user_token_number_set(symbol * sym,int user_token_number,location loc)357 symbol_user_token_number_set (symbol *sym, int user_token_number, location loc)
358 {
359 int *user_token_numberp;
360
361 if (sym->user_token_number != USER_NUMBER_HAS_STRING_ALIAS)
362 user_token_numberp = &sym->user_token_number;
363 else
364 user_token_numberp = &sym->alias->user_token_number;
365 if (*user_token_numberp != USER_NUMBER_UNDEFINED
366 && *user_token_numberp != user_token_number)
367 complain_at (loc, _("redefining user token number of %s"), sym->tag);
368
369 *user_token_numberp = user_token_number;
370 /* User defined $end token? */
371 if (user_token_number == 0)
372 {
373 endtoken = sym;
374 /* It is always mapped to 0, so it was already counted in
375 NTOKENS. */
376 if (endtoken->number != NUMBER_UNDEFINED)
377 --ntokens;
378 endtoken->number = 0;
379 }
380 }
381
382
383 /*----------------------------------------------------------.
384 | If SYM is not defined, report an error, and consider it a |
385 | nonterminal. |
386 `----------------------------------------------------------*/
387
388 static inline bool
symbol_check_defined(symbol * sym)389 symbol_check_defined (symbol *sym)
390 {
391 if (sym->class == unknown_sym)
392 {
393 complain_at
394 (sym->location,
395 _("symbol %s is used, but is not defined as a token and has no rules"),
396 sym->tag);
397 sym->class = nterm_sym;
398 sym->number = nvars++;
399 }
400
401 return true;
402 }
403
404 static bool
symbol_check_defined_processor(void * sym,void * null ATTRIBUTE_UNUSED)405 symbol_check_defined_processor (void *sym, void *null ATTRIBUTE_UNUSED)
406 {
407 return symbol_check_defined (sym);
408 }
409
410
411 void
symbol_make_alias(symbol * sym,symbol * str,location loc)412 symbol_make_alias (symbol *sym, symbol *str, location loc)
413 {
414 if (str->alias)
415 warn_at (loc, _("symbol %s used more than once as a literal string"),
416 str->tag);
417 else if (sym->alias)
418 warn_at (loc, _("symbol %s given more than one literal string"),
419 sym->tag);
420 else
421 {
422 str->class = token_sym;
423 str->user_token_number = sym->user_token_number;
424 sym->user_token_number = USER_NUMBER_HAS_STRING_ALIAS;
425 str->alias = sym;
426 sym->alias = str;
427 str->number = sym->number;
428 symbol_type_set (str, sym->type_name, loc);
429 }
430 }
431
432
433 /*---------------------------------------------------------.
434 | Check that THIS, and its alias, have same precedence and |
435 | associativity. |
436 `---------------------------------------------------------*/
437
438 static inline void
symbol_check_alias_consistency(symbol * this)439 symbol_check_alias_consistency (symbol *this)
440 {
441 symbol *sym = this;
442 symbol *str = this->alias;
443
444 /* Check only the symbol in the symbol-string pair. */
445 if (!(this->alias
446 && this->user_token_number == USER_NUMBER_HAS_STRING_ALIAS))
447 return;
448
449 if (str->type_name != sym->type_name)
450 {
451 if (str->type_name)
452 symbol_type_set (sym, str->type_name, str->type_location);
453 else
454 symbol_type_set (str, sym->type_name, sym->type_location);
455 }
456
457
458 if (str->destructor.code || sym->destructor.code)
459 {
460 if (str->destructor.code)
461 symbol_destructor_set (sym, &str->destructor);
462 else
463 symbol_destructor_set (str, &sym->destructor);
464 }
465
466 if (str->printer.code || sym->printer.code)
467 {
468 if (str->printer.code)
469 symbol_printer_set (sym, &str->printer);
470 else
471 symbol_printer_set (str, &sym->printer);
472 }
473
474 if (sym->prec || str->prec)
475 {
476 if (str->prec)
477 symbol_precedence_set (sym, str->prec, str->assoc,
478 str->prec_location);
479 else
480 symbol_precedence_set (str, sym->prec, sym->assoc,
481 sym->prec_location);
482 }
483 }
484
485 static bool
symbol_check_alias_consistency_processor(void * this,void * null ATTRIBUTE_UNUSED)486 symbol_check_alias_consistency_processor (void *this,
487 void *null ATTRIBUTE_UNUSED)
488 {
489 symbol_check_alias_consistency (this);
490 return true;
491 }
492
493
494 /*-------------------------------------------------------------------.
495 | Assign a symbol number, and write the definition of the token name |
496 | into FDEFINES. Put in SYMBOLS. |
497 `-------------------------------------------------------------------*/
498
499 static inline bool
symbol_pack(symbol * this)500 symbol_pack (symbol *this)
501 {
502 aver (this->number != NUMBER_UNDEFINED);
503 if (this->class == nterm_sym)
504 this->number += ntokens;
505 else if (this->user_token_number == USER_NUMBER_HAS_STRING_ALIAS)
506 return true;
507
508 symbols[this->number] = this;
509 return true;
510 }
511
512 static bool
symbol_pack_processor(void * this,void * null ATTRIBUTE_UNUSED)513 symbol_pack_processor (void *this, void *null ATTRIBUTE_UNUSED)
514 {
515 return symbol_pack (this);
516 }
517
518
519 static void
user_token_number_redeclaration(int num,symbol * first,symbol * second)520 user_token_number_redeclaration (int num, symbol *first, symbol *second)
521 {
522 unsigned i = 0;
523 /* User token numbers are not assigned during the parsing, but in a
524 second step, via a traversal of the symbol table sorted on tag.
525
526 However, error messages make more sense if we keep the first
527 declaration first. */
528 if (location_cmp (first->location, second->location) > 0)
529 {
530 symbol* tmp = first;
531 first = second;
532 second = tmp;
533 }
534 complain_at_indent (second->location, &i,
535 _("user token number %d redeclaration for %s"),
536 num, second->tag);
537 i += SUB_INDENT;
538 complain_at_indent (first->location, &i,
539 _("previous declaration for %s"),
540 first->tag);
541 }
542
543 /*--------------------------------------------------.
544 | Put THIS in TOKEN_TRANSLATIONS if it is a token. |
545 `--------------------------------------------------*/
546
547 static inline bool
symbol_translation(symbol * this)548 symbol_translation (symbol *this)
549 {
550 /* Non-terminal? */
551 if (this->class == token_sym
552 && this->user_token_number != USER_NUMBER_HAS_STRING_ALIAS)
553 {
554 /* A token which translation has already been set? */
555 if (token_translations[this->user_token_number] != undeftoken->number)
556 user_token_number_redeclaration
557 (this->user_token_number,
558 symbols[token_translations[this->user_token_number]],
559 this);
560
561 token_translations[this->user_token_number] = this->number;
562 }
563
564 return true;
565 }
566
567 static bool
symbol_translation_processor(void * this,void * null ATTRIBUTE_UNUSED)568 symbol_translation_processor (void *this, void *null ATTRIBUTE_UNUSED)
569 {
570 return symbol_translation (this);
571 }
572
573
574 /*---------------------------------------.
575 | Symbol and semantic type hash tables. |
576 `---------------------------------------*/
577
578 /* Initial capacity of symbol and semantic type hash table. */
579 #define HT_INITIAL_CAPACITY 257
580
581 static struct hash_table *symbol_table = NULL;
582 static struct hash_table *semantic_type_table = NULL;
583
584 static inline bool
hash_compare_symbol(const symbol * m1,const symbol * m2)585 hash_compare_symbol (const symbol *m1, const symbol *m2)
586 {
587 /* Since tags are unique, we can compare the pointers themselves. */
588 return UNIQSTR_EQ (m1->tag, m2->tag);
589 }
590
591 static inline bool
hash_compare_semantic_type(const semantic_type * m1,const semantic_type * m2)592 hash_compare_semantic_type (const semantic_type *m1, const semantic_type *m2)
593 {
594 /* Since names are unique, we can compare the pointers themselves. */
595 return UNIQSTR_EQ (m1->tag, m2->tag);
596 }
597
598 static bool
hash_symbol_comparator(void const * m1,void const * m2)599 hash_symbol_comparator (void const *m1, void const *m2)
600 {
601 return hash_compare_symbol (m1, m2);
602 }
603
604 static bool
hash_semantic_type_comparator(void const * m1,void const * m2)605 hash_semantic_type_comparator (void const *m1, void const *m2)
606 {
607 return hash_compare_semantic_type (m1, m2);
608 }
609
610 static inline size_t
hash_symbol(const symbol * m,size_t tablesize)611 hash_symbol (const symbol *m, size_t tablesize)
612 {
613 /* Since tags are unique, we can hash the pointer itself. */
614 return ((uintptr_t) m->tag) % tablesize;
615 }
616
617 static inline size_t
hash_semantic_type(const semantic_type * m,size_t tablesize)618 hash_semantic_type (const semantic_type *m, size_t tablesize)
619 {
620 /* Since names are unique, we can hash the pointer itself. */
621 return ((uintptr_t) m->tag) % tablesize;
622 }
623
624 static size_t
hash_symbol_hasher(void const * m,size_t tablesize)625 hash_symbol_hasher (void const *m, size_t tablesize)
626 {
627 return hash_symbol (m, tablesize);
628 }
629
630 static size_t
hash_semantic_type_hasher(void const * m,size_t tablesize)631 hash_semantic_type_hasher (void const *m, size_t tablesize)
632 {
633 return hash_semantic_type (m, tablesize);
634 }
635
636 /*-------------------------------.
637 | Create the symbol hash table. |
638 `-------------------------------*/
639
640 void
symbols_new(void)641 symbols_new (void)
642 {
643 symbol_table = hash_initialize (HT_INITIAL_CAPACITY,
644 NULL,
645 hash_symbol_hasher,
646 hash_symbol_comparator,
647 free);
648 semantic_type_table = hash_initialize (HT_INITIAL_CAPACITY,
649 NULL,
650 hash_semantic_type_hasher,
651 hash_semantic_type_comparator,
652 free);
653 }
654
655
656 /*----------------------------------------------------------------.
657 | Find the symbol named KEY, and return it. If it does not exist |
658 | yet, create it. |
659 `----------------------------------------------------------------*/
660
661 symbol *
symbol_from_uniqstr(const uniqstr key,location loc)662 symbol_from_uniqstr (const uniqstr key, location loc)
663 {
664 symbol probe;
665 symbol *entry;
666
667 probe.tag = key;
668 entry = hash_lookup (symbol_table, &probe);
669
670 if (!entry)
671 {
672 /* First insertion in the hash. */
673 aver (!symbols_sorted);
674 entry = symbol_new (key, loc);
675 if (!hash_insert (symbol_table, entry))
676 xalloc_die ();
677 }
678 return entry;
679 }
680
681
682 /*-----------------------------------------------------------------------.
683 | Find the semantic type named KEY, and return it. If it does not exist |
684 | yet, create it. |
685 `-----------------------------------------------------------------------*/
686
687 semantic_type *
semantic_type_from_uniqstr(const uniqstr key)688 semantic_type_from_uniqstr (const uniqstr key)
689 {
690 semantic_type probe;
691 semantic_type *entry;
692
693 probe.tag = key;
694 entry = hash_lookup (semantic_type_table, &probe);
695
696 if (!entry)
697 {
698 /* First insertion in the hash. */
699 entry = semantic_type_new (key);
700 if (!hash_insert (semantic_type_table, entry))
701 xalloc_die ();
702 }
703 return entry;
704 }
705
706
707 /*----------------------------------------------------------------.
708 | Find the symbol named KEY, and return it. If it does not exist |
709 | yet, create it. |
710 `----------------------------------------------------------------*/
711
712 symbol *
symbol_get(const char * key,location loc)713 symbol_get (const char *key, location loc)
714 {
715 return symbol_from_uniqstr (uniqstr_new (key), loc);
716 }
717
718
719 /*-----------------------------------------------------------------------.
720 | Find the semantic type named KEY, and return it. If it does not exist |
721 | yet, create it. |
722 `-----------------------------------------------------------------------*/
723
724 semantic_type *
semantic_type_get(const char * key)725 semantic_type_get (const char *key)
726 {
727 return semantic_type_from_uniqstr (uniqstr_new (key));
728 }
729
730
731 /*------------------------------------------------------------------.
732 | Generate a dummy nonterminal, whose name cannot conflict with the |
733 | user's names. |
734 `------------------------------------------------------------------*/
735
736 symbol *
dummy_symbol_get(location loc)737 dummy_symbol_get (location loc)
738 {
739 /* Incremented for each generated symbol. */
740 static int dummy_count = 0;
741 static char buf[256];
742
743 symbol *sym;
744
745 sprintf (buf, "$@%d", ++dummy_count);
746 sym = symbol_get (buf, loc);
747 sym->class = nterm_sym;
748 sym->number = nvars++;
749 return sym;
750 }
751
752 bool
symbol_is_dummy(const symbol * sym)753 symbol_is_dummy (const symbol *sym)
754 {
755 return sym->tag[0] == '@' || (sym->tag[0] == '$' && sym->tag[1] == '@');
756 }
757
758 /*-------------------.
759 | Free the symbols. |
760 `-------------------*/
761
762 void
symbols_free(void)763 symbols_free (void)
764 {
765 hash_free (symbol_table);
766 hash_free (semantic_type_table);
767 free (symbols);
768 free (symbols_sorted);
769 }
770
771
772 /*---------------------------------------------------------------.
773 | Look for undefined symbols, report an error, and consider them |
774 | terminals. |
775 `---------------------------------------------------------------*/
776
777 static int
symbols_cmp(symbol const * a,symbol const * b)778 symbols_cmp (symbol const *a, symbol const *b)
779 {
780 return strcmp (a->tag, b->tag);
781 }
782
783 static int
symbols_cmp_qsort(void const * a,void const * b)784 symbols_cmp_qsort (void const *a, void const *b)
785 {
786 return symbols_cmp (*(symbol * const *)a, *(symbol * const *)b);
787 }
788
789 static void
symbols_do(Hash_processor processor,void * processor_data)790 symbols_do (Hash_processor processor, void *processor_data)
791 {
792 size_t count = hash_get_n_entries (symbol_table);
793 if (!symbols_sorted)
794 {
795 symbols_sorted = xnmalloc (count, sizeof *symbols_sorted);
796 hash_get_entries (symbol_table, (void**)symbols_sorted, count);
797 qsort (symbols_sorted, count, sizeof *symbols_sorted,
798 symbols_cmp_qsort);
799 }
800 {
801 size_t i;
802 for (i = 0; i < count; ++i)
803 processor (symbols_sorted[i], processor_data);
804 }
805 }
806
807 /*--------------------------------------------------------------.
808 | Check that all the symbols are defined. Report any undefined |
809 | symbols and consider them nonterminals. |
810 `--------------------------------------------------------------*/
811
812 void
symbols_check_defined(void)813 symbols_check_defined (void)
814 {
815 symbols_do (symbol_check_defined_processor, NULL);
816 }
817
818 /*------------------------------------------------------------------.
819 | Set TOKEN_TRANSLATIONS. Check that no two symbols share the same |
820 | number. |
821 `------------------------------------------------------------------*/
822
823 static void
symbols_token_translations_init(void)824 symbols_token_translations_init (void)
825 {
826 bool num_256_available_p = true;
827 int i;
828
829 /* Find the highest user token number, and whether 256, the POSIX
830 preferred user token number for the error token, is used. */
831 max_user_token_number = 0;
832 for (i = 0; i < ntokens; ++i)
833 {
834 symbol *this = symbols[i];
835 if (this->user_token_number != USER_NUMBER_UNDEFINED)
836 {
837 if (this->user_token_number > max_user_token_number)
838 max_user_token_number = this->user_token_number;
839 if (this->user_token_number == 256)
840 num_256_available_p = false;
841 }
842 }
843
844 /* If 256 is not used, assign it to error, to follow POSIX. */
845 if (num_256_available_p
846 && errtoken->user_token_number == USER_NUMBER_UNDEFINED)
847 errtoken->user_token_number = 256;
848
849 /* Set the missing user numbers. */
850 if (max_user_token_number < 256)
851 max_user_token_number = 256;
852
853 for (i = 0; i < ntokens; ++i)
854 {
855 symbol *this = symbols[i];
856 if (this->user_token_number == USER_NUMBER_UNDEFINED)
857 this->user_token_number = ++max_user_token_number;
858 if (this->user_token_number > max_user_token_number)
859 max_user_token_number = this->user_token_number;
860 }
861
862 token_translations = xnmalloc (max_user_token_number + 1,
863 sizeof *token_translations);
864
865 /* Initialize all entries for literal tokens to 2, the internal
866 token number for $undefined, which represents all invalid inputs.
867 */
868 for (i = 0; i < max_user_token_number + 1; i++)
869 token_translations[i] = undeftoken->number;
870 symbols_do (symbol_translation_processor, NULL);
871 }
872
873
874 /*----------------------------------------------------------------.
875 | Assign symbol numbers, and write definition of token names into |
876 | FDEFINES. Set up vectors SYMBOL_TABLE, TAGS of symbols. |
877 `----------------------------------------------------------------*/
878
879 void
symbols_pack(void)880 symbols_pack (void)
881 {
882 symbols_do (symbol_check_alias_consistency_processor, NULL);
883
884 symbols = xcalloc (nsyms, sizeof *symbols);
885 symbols_do (symbol_pack_processor, NULL);
886
887 /* Aliases leave empty slots in symbols, so remove them. */
888 {
889 int writei;
890 int readi;
891 int nsyms_old = nsyms;
892 for (writei = 0, readi = 0; readi < nsyms_old; readi += 1)
893 {
894 if (symbols[readi] == NULL)
895 {
896 nsyms -= 1;
897 ntokens -= 1;
898 }
899 else
900 {
901 symbols[writei] = symbols[readi];
902 symbols[writei]->number = writei;
903 if (symbols[writei]->alias)
904 symbols[writei]->alias->number = writei;
905 writei += 1;
906 }
907 }
908 }
909 symbols = xnrealloc (symbols, nsyms, sizeof *symbols);
910
911 symbols_token_translations_init ();
912
913 if (startsymbol->class == unknown_sym)
914 fatal_at (startsymbol_location,
915 _("the start symbol %s is undefined"),
916 startsymbol->tag);
917 else if (startsymbol->class == token_sym)
918 fatal_at (startsymbol_location,
919 _("the start symbol %s is a token"),
920 startsymbol->tag);
921 }
922
923
924 /*--------------------------------------------------.
925 | Set default tagged/tagless %destructor/%printer. |
926 `--------------------------------------------------*/
927
928 void
default_tagged_destructor_set(code_props const * destructor)929 default_tagged_destructor_set (code_props const *destructor)
930 {
931 if (default_tagged_destructor.code)
932 {
933 unsigned i = 0;
934 complain_at_indent (destructor->location, &i,
935 _("redeclaration for default tagged %%destructor"));
936 i += SUB_INDENT;
937 complain_at_indent (default_tagged_destructor.location, &i,
938 _("previous declaration"));
939 }
940 default_tagged_destructor = *destructor;
941 }
942
943 void
default_tagless_destructor_set(code_props const * destructor)944 default_tagless_destructor_set (code_props const *destructor)
945 {
946 if (default_tagless_destructor.code)
947 {
948 unsigned i = 0;
949 complain_at_indent (destructor->location, &i,
950 _("redeclaration for default tagless %%destructor"));
951 i += SUB_INDENT;
952 complain_at_indent (default_tagless_destructor.location, &i,
953 _("previous declaration"));
954 }
955 default_tagless_destructor = *destructor;
956 }
957
958 void
default_tagged_printer_set(code_props const * printer)959 default_tagged_printer_set (code_props const *printer)
960 {
961 if (default_tagged_printer.code)
962 {
963 unsigned i = 0;
964 complain_at_indent (printer->location, &i,
965 _("redeclaration for default tagged %%printer"));
966 i += SUB_INDENT;
967 complain_at_indent (default_tagged_printer.location, &i,
968 _("previous declaration"));
969 }
970 default_tagged_printer = *printer;
971 }
972
973 void
default_tagless_printer_set(code_props const * printer)974 default_tagless_printer_set (code_props const *printer)
975 {
976 if (default_tagless_printer.code)
977 {
978 unsigned i = 0;
979 complain_at_indent (printer->location, &i,
980 _("redeclaration for default tagless %%printer"));
981 i += SUB_INDENT;
982 complain_at_indent (default_tagless_printer.location, &i,
983 _("previous declaration"));
984 }
985 default_tagless_printer = *printer;
986 }
987