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1/* Output the generated parsing program for bison,
2 Copyright (C) 1984, 1986, 1989, 1992, 2000, 2001, 2002
3 Free Software Foundation, Inc.
4
5 This file is part of Bison, the GNU Compiler Compiler.
6
7 Bison is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
11
12 Bison is distributed in the hope that it will be useful, but
13 WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with Bison; see the file COPYING. If not, write to the Free
19 Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
21
22
23/* The parser tables consist of these tables.
24
25 YYTRANSLATE = vector mapping yylex's token numbers into bison's
26 token numbers.
27
28 YYTNAME = vector of string-names indexed by bison token number.
29
30 YYTOKNUM = vector of yylex token numbers corresponding to entries
31 in YYTNAME.
32
33 YYRLINE = vector of line-numbers of all rules. For yydebug
34 printouts.
35
36 YYRHS = vector of items of all rules. This is exactly what RITEMS
37 contains. For yydebug and for semantic parser.
38
39 YYPRHS[R] = index in YYRHS of first item for rule R.
40
41 YYR1[R] = symbol number of symbol that rule R derives.
42
43 YYR2[R] = number of symbols composing right hand side of rule R.
44
45 YYSTOS[S] = the symbol number of the symbol that leads to state S.
46
47 YYDEFACT[S] = default rule to reduce with in state s, when YYTABLE
48 doesn't specify something else to do. Zero means the default is an
49 error.
50
51 YYDEFGOTO[I] = default state to go to after a reduction of a rule
52 that generates variable NTOKENS + I, except when YYTABLE specifies
53 something else to do.
54
55 YYPACT[S] = index in YYTABLE of the portion describing state S.
56 The lookahead token's type is used to index that portion to find
57 out what to do.
58
59 If the value in YYTABLE is positive, we shift the token and go to
60 that state.
61
62 If the value is negative, it is minus a rule number to reduce by.
63
64 If the value is zero, the default action from YYDEFACT[S] is used.
65
66 YYPGOTO[I] = the index in YYTABLE of the portion describing what to
67 do after reducing a rule that derives variable I + NTOKENS. This
68 portion is indexed by the parser state number, S, as of before the
69 text for this nonterminal was read. The value from YYTABLE is the
70 state to go to if the corresponding value in YYCHECK is S.
71
72 YYTABLE = a vector filled with portions for different uses, found
73 via YYPACT and YYPGOTO.
74
75 YYCHECK = a vector indexed in parallel with YYTABLE. It indicates,
76 in a roundabout way, the bounds of the portion you are trying to
77 examine.
78
79 Suppose that the portion of YYTABLE starts at index P and the index
80 to be examined within the portion is I. Then if YYCHECK[P+I] != I,
81 I is outside the bounds of what is actually allocated, and the
82 default (from YYDEFACT or YYDEFGOTO) should be used. Otherwise,
83 YYTABLE[P+I] should be used.
84
85 YYFINAL = the state number of the termination state. YYFLAG = most
86 negative short int. Used to flag ?? */
87
88#include "system.h"
89#include "bitsetv.h"
90#include "quotearg.h"
91#include "getargs.h"
92#include "files.h"
93#include "gram.h"
94#include "complain.h"
95#include "lalr.h"
96#include "reader.h"
97#include "symtab.h"
98#include "conflicts.h"
99#include "tables.h"
100
101/* Several tables will be indexed both by state and nonterminal
102 numbers. We call `vector' such a thing (= either a state or a
103 symbol number.
104
105 Of course vector_number_t ought to be wide enough to contain
106 state_number_t and symbol_number_t. */
107typedef short vector_number_t;
108#define VECTOR_NUMBER_MAX ((vector_number_t) SHRT_MAX)
109#define VECTOR_NUMBER_MIN ((vector_number_t) SHRT_MIN)
110#define state_number_to_vector_number(State) \
111 ((vector_number_t) State)
112#define symbol_number_to_vector_number(Symbol) \
113 ((vector_number_t) (state_number_as_int (nstates) + Symbol - ntokens))
114
115int nvectors;
116
117
118/* FROMS and TOS are indexed by vector_number_t.
119
120 If VECTOR is a nonterminal, (FROMS[VECTOR], TOS[VECTOR]) form an
121 array of state numbers of the non defaulted GOTO on VECTOR.
122
123 If VECTOR is a state, TOS[VECTOR] is the array of actions to do on
124 the (array of) symbols FROMS[VECTOR].
125
126 In both cases, TALLY[VECTOR] is the size of the arrays
127 FROMS[VECTOR], TOS[VECTOR]; and WIDTH[VECTOR] =
128 (FROMS[VECTOR][SIZE] - FROMS[VECTOR][0] + 1) where SIZE =
129 TALLY[VECTOR].
130
131 FROMS therefore contains symbol_number_t and action_number_t,
132 TOS state_number_t and action_number_t,
133 TALLY sizes,
134 WIDTH differences of FROMS.
135
136 Let base_t be the type of FROMS, TOS, and WIDTH. */
137#define BASE_MAX ((base_t) INT_MAX)
138#define BASE_MIN ((base_t) INT_MIN)
139
140static base_t **froms = NULL;
141static base_t **tos = NULL;
142static unsigned int **conflict_tos = NULL;
143static short *tally = NULL;
144static base_t *width = NULL;
145
146
147/* For a given state, N = ACTROW[SYMBOL]:
148
149 If N = 0, stands for `run the default action'.
150 If N = MIN, stands for `raise a parse error'.
151 If N > 0, stands for `shift SYMBOL and go to n'.
152 If N < 0, stands for `reduce -N'. */
153typedef short action_t;
154#define ACTION_MAX ((action_t) SHRT_MAX)
155#define ACTION_MIN ((action_t) SHRT_MIN)
156
157static action_t *actrow = NULL;
158
159/* FROMS and TOS are reordered to be compressed. ORDER[VECTOR] is the
160 new vector number of VECTOR. We skip `empty' vectors (i.e.,
161 TALLY[VECTOR] = 0), and call these `entries'. */
162static vector_number_t *order = NULL;
163static int nentries;
164
165base_t *base = NULL;
166/* A distinguished value of BASE, negative infinite. During the
167 computation equals to BASE_MIN, later mapped to BASE_NINF to
168 keep parser tables small. */
169base_t base_ninf = 0;
170static base_t *pos = NULL;
171
172static unsigned int *conflrow = NULL;
173unsigned int *conflict_table = NULL;
174unsigned int *conflict_list = NULL;
175int conflict_list_cnt;
176static int conflict_list_free;
177
178/* TABLE_SIZE is the allocated size of both TABLE and CHECK. We start
179 with more or less the original hard-coded value (which was
180 SHRT_MAX). */
181static size_t table_size = 32768;
182base_t *table = NULL;
183base_t *check = NULL;
184/* The value used in TABLE to denote explicit parse errors
185 (%nonassoc), a negative infinite. First defaults to ACTION_MIN,
186 but in order to keep small tables, renumbered as TABLE_ERROR, which
187 is the smallest (non error) value minus 1. */
188base_t table_ninf = 0;
189static int lowzero;
190int high;
191
192state_number_t *yydefgoto;
193rule_number_t *yydefact;
194
195/*----------------------------------------------------------------.
196| If TABLE (and CHECK) appear to be small to be addressed at |
197| DESIRED, grow them. Note that TABLE[DESIRED] is to be used, so |
198| the desired size is at least DESIRED + 1. |
199`----------------------------------------------------------------*/
200
201static void
202table_grow (size_t desired)
203{
204 size_t old_size = table_size;
205
206 while (table_size <= desired)
207 table_size *= 2;
208
209 if (trace_flag & trace_resource)
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210 fprintf (stderr, "growing table and check from: %d to %d\n",
211 old_size, table_size);
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212
213 table = XREALLOC (table, base_t, table_size);
214 check = XREALLOC (check, base_t, table_size);
ea99527d 215 conflict_table = XREALLOC (conflict_table, unsigned int, table_size);
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216
217 for (/* Nothing. */; old_size < table_size; ++old_size)
218 {
219 table[old_size] = 0;
220 check[old_size] = -1;
221 }
222}
223
224
225
226
227/*-------------------------------------------------------------------.
228| For GLR parsers, for each conflicted token in STATE, as indicated |
229| by non-zero entries in CONFLROW, create a list of possible |
230| reductions that are alternatives to the shift or reduction |
231| currently recorded for that token in STATE. Store the alternative |
232| reductions followed by a 0 in CONFLICT_LIST, updating |
233| CONFLICT_LIST_CNT, and storing an index to the start of the list |
234| back into CONFLROW. |
235`-------------------------------------------------------------------*/
236
237static void
238conflict_row (state_t *state)
239{
240 int i, j;
cd08e51e 241 reductions_t *reds = state->reductions;
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242
243 if (! glr_parser)
244 return;
245
246 for (j = 0; j < ntokens; j += 1)
247 if (conflrow[j])
248 {
249 conflrow[j] = conflict_list_cnt;
250
251 /* Find all reductions for token J, and record all that do not
252 match ACTROW[J]. */
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253 for (i = 0; i < reds->num; i += 1)
254 if (bitset_test (reds->lookaheads[i], j)
c6f1a33c 255 && (actrow[j]
cd08e51e 256 != rule_number_as_item_number (reds->rules[i]->number)))
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257 {
258 assert (conflict_list_free > 0);
cd08e51e 259 conflict_list[conflict_list_cnt] = reds->rules[i]->number + 1;
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260 conflict_list_cnt += 1;
261 conflict_list_free -= 1;
262 }
263
264 /* Leave a 0 at the end. */
265 assert (conflict_list_free > 0);
266 conflict_list_cnt += 1;
267 conflict_list_free -= 1;
268 }
269}
270
271
272/*------------------------------------------------------------------.
273| Decide what to do for each type of token if seen as the lookahead |
274| token in specified state. The value returned is used as the |
275| default action (yydefact) for the state. In addition, ACTROW is |
276| filled with what to do for each kind of token, index by symbol |
277| number, with zero meaning do the default action. The value |
278| ACTION_MIN, a very negative number, means this situation is an |
279| error. The parser recognizes this value specially. |
280| |
281| This is where conflicts are resolved. The loop over lookahead |
282| rules considered lower-numbered rules last, and the last rule |
283| considered that likes a token gets to handle it. |
284| |
285| For GLR parsers, also sets CONFLROW[SYM] to an index into |
286| CONFLICT_LIST iff there is an unresolved conflict (s/r or r/r) |
287| with symbol SYM. The default reduction is not used for a symbol |
288| that has any such conflicts. |
289`------------------------------------------------------------------*/
290
291static rule_t *
292action_row (state_t *state)
293{
294 int i;
295 rule_t *default_rule = NULL;
296 reductions_t *redp = state->reductions;
297 transitions_t *transitions = state->transitions;
298 errs_t *errp = state->errs;
299 /* Set to nonzero to inhibit having any default reduction. */
300 int nodefault = 0;
301 int conflicted = 0;
302
303 for (i = 0; i < ntokens; i++)
304 actrow[i] = conflrow[i] = 0;
305
cd08e51e 306 if (redp->lookaheads)
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307 {
308 int j;
309 bitset_iterator biter;
310 /* loop over all the rules available here which require
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311 lookahead (in reverse order to give precedence to the first
312 rule) */
313 for (i = redp->num - 1; i >= 0; --i)
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314 /* and find each token which the rule finds acceptable
315 to come next */
cd08e51e 316 BITSET_FOR_EACH (biter, redp->lookaheads[i], j, 0)
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317 {
318 /* and record this rule as the rule to use if that
319 token follows. */
320 if (actrow[j] != 0)
321 conflicted = conflrow[j] = 1;
cd08e51e 322 actrow[j] = rule_number_as_item_number (redp->rules[i]->number);
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323 }
324 }
325
326 /* Now see which tokens are allowed for shifts in this state. For
327 them, record the shift as the thing to do. So shift is preferred
328 to reduce. */
329 FOR_EACH_SHIFT (transitions, i)
330 {
331 symbol_number_t symbol = TRANSITION_SYMBOL (transitions, i);
332 state_t *shift_state = transitions->states[i];
333
334 if (actrow[symbol] != 0)
335 conflicted = conflrow[symbol] = 1;
336 actrow[symbol] = state_number_as_int (shift_state->number);
337
338 /* Do not use any default reduction if there is a shift for
339 error */
340 if (symbol == errtoken->number)
341 nodefault = 1;
342 }
343
344 /* See which tokens are an explicit error in this state (due to
345 %nonassoc). For them, record ACTION_MIN as the action. */
346 for (i = 0; i < errp->num; i++)
347 {
348 symbol_t *symbol = errp->symbols[i];
349 actrow[symbol->number] = ACTION_MIN;
350 }
351
352 /* Now find the most common reduction and make it the default action
353 for this state. */
354
355 if (redp->num >= 1 && !nodefault)
356 {
357 if (state->consistent)
358 default_rule = redp->rules[0];
359 else
360 {
361 int max = 0;
cd08e51e 362 for (i = 0; i < redp->num; i++)
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363 {
364 int count = 0;
cd08e51e 365 rule_t *rule = redp->rules[i];
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366 symbol_number_t j;
367
368 for (j = 0; j < ntokens; j++)
369 if (actrow[j] == rule_number_as_item_number (rule->number))
370 count++;
371
372 if (count > max)
373 {
374 max = count;
375 default_rule = rule;
376 }
377 }
378
379 /* GLR parsers need space for conflict lists, so we can't
380 default conflicted entries. For non-conflicted entries
381 or as long as we are not building a GLR parser,
382 actions that match the default are replaced with zero,
383 which means "use the default". */
384
385 if (max > 0)
386 {
387 int j;
388 for (j = 0; j < ntokens; j++)
389 if (actrow[j] == rule_number_as_item_number (default_rule->number)
390 && ! (glr_parser && conflrow[j]))
391 actrow[j] = 0;
392 }
393 }
394 }
395
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396 /* If have no default rule, the default is an error.
397 So replace any action which says "error" with "use default". */
398
399 if (!default_rule)
400 for (i = 0; i < ntokens; i++)
401 if (actrow[i] == ACTION_MIN)
402 actrow[i] = 0;
403
404 if (conflicted)
405 conflict_row (state);
406
407 return default_rule;
408}
409
410
411/*--------------------------------------------.
412| Set FROMS, TOS, TALLY and WIDTH for STATE. |
413`--------------------------------------------*/
414
415static void
416save_row (state_number_t state)
417{
418 symbol_number_t i;
419 int count;
420 base_t *sp = NULL;
421 base_t *sp1 = NULL;
422 base_t *sp2 = NULL;
423 unsigned int *sp3 = NULL;
424
425 /* Number of non default actions in STATE. */
426 count = 0;
427 for (i = 0; i < ntokens; i++)
428 if (actrow[i] != 0)
429 count++;
430
431 if (count == 0)
432 return;
433
434 /* Allocate non defaulted actions. */
435 froms[state] = sp1 = sp = XCALLOC (base_t, count);
436 tos[state] = sp2 = XCALLOC (base_t, count);
437 if (glr_parser)
438 conflict_tos[state] = sp3 = XCALLOC (unsigned int, count);
439 else
440 conflict_tos[state] = NULL;
441
442 /* Store non defaulted actions. */
443 for (i = 0; i < ntokens; i++)
444 if (actrow[i] != 0)
445 {
446 *sp1++ = i;
447 *sp2++ = actrow[i];
448 if (glr_parser)
449 *sp3++ = conflrow[i];
450 }
451
452 tally[state] = count;
453 width[state] = sp1[-1] - sp[0] + 1;
454}
455
456
457/*------------------------------------------------------------------.
458| Figure out the actions for the specified state, indexed by |
459| lookahead token type. |
460| |
461| The YYDEFACT table is output now. The detailed info is saved for |
462| putting into YYTABLE later. |
463`------------------------------------------------------------------*/
464
465static void
466token_actions (void)
467{
468 state_number_t i;
c8f002c7 469 symbol_number_t j;
c6f1a33c 470 rule_number_t r;
c8f002c7 471
ea99527d 472 int nconflict = glr_parser ? conflicts_total_count () : 0;
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473
474 yydefact = XCALLOC (rule_number_t, nstates);
475
476 actrow = XCALLOC (action_t, ntokens);
477 conflrow = XCALLOC (unsigned int, ntokens);
478
ea99527d
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479 conflict_list = XCALLOC (unsigned int, 1 + 2 * nconflict);
480 conflict_list_free = 2 * nconflict;
481 conflict_list_cnt = 1;
482
c8f002c7 483 /* Find the rules which are reduced. */
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484 if (!glr_parser)
485 for (r = 0; r < nrules; ++r)
486 rules[r].useful = FALSE;
487
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488 for (i = 0; i < nstates; ++i)
489 {
490 rule_t *default_rule = action_row (states[i]);
491 yydefact[i] = default_rule ? default_rule->number + 1 : 0;
492 save_row (i);
c6f1a33c 493
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494 /* Now that the parser was computed, we can find which rules are
495 really reduced, and which are not because of SR or RR
496 conflicts. */
497 if (!glr_parser)
c6f1a33c 498 {
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499 for (j = 0; j < ntokens; ++j)
500 if (actrow[j] < 0 && actrow[j] != ACTION_MIN)
501 rules[item_number_as_rule_number (actrow[j])].useful = TRUE;
502 if (yydefact[i])
503 rules[yydefact[i] - 1].useful = TRUE;
c6f1a33c 504 }
c8f002c7 505 }
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506
507 free (actrow);
508 free (conflrow);
509}
510
511
512/*------------------------------------------------------------------.
513| Compute FROMS[VECTOR], TOS[VECTOR], TALLY[VECTOR], WIDTH[VECTOR], |
514| i.e., the information related to non defaulted GOTO on the nterm |
515| SYMBOL. |
516| |
517| DEFAULT_STATE is the principal destination on SYMBOL, i.e., the |
518| default GOTO destination on SYMBOL. |
519`------------------------------------------------------------------*/
520
521static void
522save_column (symbol_number_t symbol, state_number_t default_state)
523{
524 int i;
525 base_t *sp;
526 base_t *sp1;
527 base_t *sp2;
528 int count;
529 vector_number_t symno = symbol_number_to_vector_number (symbol);
530
531 goto_number_t begin = goto_map[symbol];
532 goto_number_t end = goto_map[symbol + 1];
533
534 /* Number of non default GOTO. */
535 count = 0;
536 for (i = begin; i < end; i++)
537 if (to_state[i] != default_state)
538 count++;
539
540 if (count == 0)
541 return;
542
543 /* Allocate room for non defaulted gotos. */
544 froms[symno] = sp1 = sp = XCALLOC (base_t, count);
545 tos[symno] = sp2 = XCALLOC (base_t, count);
546
547 /* Store the state numbers of the non defaulted gotos. */
548 for (i = begin; i < end; i++)
549 if (to_state[i] != default_state)
550 {
551 *sp1++ = from_state[i];
552 *sp2++ = to_state[i];
553 }
554
555 tally[symno] = count;
556 width[symno] = sp1[-1] - sp[0] + 1;
557}
558
559
560/*----------------------------------------------------------------.
561| Return `the' most common destination GOTO on SYMBOL (a nterm). |
562`----------------------------------------------------------------*/
563
564static state_number_t
565default_goto (symbol_number_t symbol, short state_count[])
566{
567 state_number_t s;
568 int i;
569 goto_number_t m = goto_map[symbol];
570 goto_number_t n = goto_map[symbol + 1];
571 state_number_t default_state = (state_number_t) -1;
572 int max = 0;
573
574 if (m == n)
575 return (state_number_t) -1;
576
577 for (s = 0; s < nstates; s++)
578 state_count[s] = 0;
579
580 for (i = m; i < n; i++)
581 state_count[to_state[i]]++;
582
583 for (s = 0; s < nstates; s++)
584 if (state_count[s] > max)
585 {
586 max = state_count[s];
587 default_state = s;
588 }
589
590 return default_state;
591}
592
593
594/*-------------------------------------------------------------------.
595| Figure out what to do after reducing with each rule, depending on |
596| the saved state from before the beginning of parsing the data that |
597| matched this rule. |
598| |
599| The YYDEFGOTO table is output now. The detailed info is saved for |
600| putting into YYTABLE later. |
601`-------------------------------------------------------------------*/
602
603static void
604goto_actions (void)
605{
606 symbol_number_t i;
607 short *state_count = XCALLOC (short, nstates);
608 yydefgoto = XMALLOC (state_number_t, nvars);
609
610 /* For a given nterm I, STATE_COUNT[S] is the number of times there
611 is a GOTO to S on I. */
612 for (i = ntokens; i < nsyms; ++i)
613 {
614 state_number_t default_state = default_goto (i, state_count);
615 save_column (i, default_state);
616 yydefgoto[i - ntokens] = default_state;
617 }
618 free (state_count);
619}
620
621
622/*------------------------------------------------------------------.
623| Compute ORDER, a reordering of vectors, in order to decide how to |
624| pack the actions and gotos information into yytable. |
625`------------------------------------------------------------------*/
626
627static void
628sort_actions (void)
629{
630 int i;
631
632 nentries = 0;
633
634 for (i = 0; i < nvectors; i++)
635 if (tally[i] > 0)
636 {
637 int k;
638 int t = tally[i];
639 int w = width[i];
640 int j = nentries - 1;
641
642 while (j >= 0 && (width[order[j]] < w))
643 j--;
644
645 while (j >= 0 && (width[order[j]] == w) && (tally[order[j]] < t))
646 j--;
647
648 for (k = nentries - 1; k > j; k--)
649 order[k + 1] = order[k];
650
651 order[j + 1] = i;
652 nentries++;
653 }
654}
655
656
657/* If VECTOR is a state which actions (reflected by FROMS, TOS, TALLY
658 and WIDTH of VECTOR) are common to a previous state, return this
659 state number.
660
661 In any other case, return -1. */
662
663static state_number_t
664matching_state (vector_number_t vector)
665{
666 vector_number_t i = order[vector];
667 int t;
668 int w;
669 int prev;
670
671 /* If VECTOR is a nterm, return -1. */
672 if (i >= (int) nstates)
673 return -1;
674
675 t = tally[i];
676 w = width[i];
677
678 for (prev = vector - 1; prev >= 0; prev--)
679 {
680 vector_number_t j = order[prev];
681 int k;
682 int match = 1;
683
684 /* Given how ORDER was computed, if the WIDTH or TALLY is
685 different, there cannot be a matching state. */
686 if (width[j] != w || tally[j] != t)
687 return -1;
688
689 for (k = 0; match && k < t; k++)
690 if (tos[j][k] != tos[i][k] || froms[j][k] != froms[i][k])
691 match = 0;
692
693 if (match)
694 return j;
695 }
696
697 return -1;
698}
699
700
701static base_t
702pack_vector (vector_number_t vector)
703{
704 vector_number_t i = order[vector];
705 int j;
706 int t = tally[i];
707 int loc = 0;
708 base_t *from = froms[i];
709 base_t *to = tos[i];
710 unsigned int *conflict_to = conflict_tos[i];
711
712 assert (t);
713
714 for (j = lowzero - from[0]; j < (int) table_size; j++)
715 {
716 int k;
717 int ok = 1;
718
719 for (k = 0; ok && k < t; k++)
720 {
721 loc = j + state_number_as_int (from[k]);
3325ddc4 722 if (loc >= (int) table_size)
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723 table_grow (loc);
724
725 if (table[loc] != 0)
726 ok = 0;
727 }
728
729 for (k = 0; ok && k < vector; k++)
730 if (pos[k] == j)
731 ok = 0;
732
733 if (ok)
734 {
735 for (k = 0; k < t; k++)
736 {
737 loc = j + from[k];
738 table[loc] = to[k];
739 if (glr_parser && conflict_to != NULL)
740 conflict_table[loc] = conflict_to[k];
741 check[loc] = from[k];
742 }
743
744 while (table[lowzero] != 0)
745 lowzero++;
746
747 if (loc > high)
748 high = loc;
749
750 if (j < BASE_MIN || BASE_MAX < j)
427c0dda 751 fatal ("base_t too small to hold %d\n", j);
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752 return j;
753 }
754 }
755#define pack_vector_succeeded 0
756 assert (pack_vector_succeeded);
757 return 0;
758}
759
760
761/*-------------------------------------------------------------.
762| Remap the negative infinite in TAB from NINF to the greatest |
763| possible smallest value. Return it. |
764| |
765| In most case this allows us to use shorts instead of ints in |
766| parsers. |
767`-------------------------------------------------------------*/
768
769static base_t
770table_ninf_remap (base_t tab[], size_t size, base_t ninf)
771{
772 base_t res = 0;
773 size_t i;
774
775 for (i = 0; i < size; i++)
776 if (tab[i] < res && tab[i] != ninf)
05846dae 777 res = tab[i];
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778
779 --res;
780
781 for (i = 0; i < size; i++)
782 if (tab[i] == ninf)
783 tab[i] = res;
784
785 return res;
786}
787
788static void
789pack_table (void)
790{
791 int i;
792
793 base = XCALLOC (base_t, nvectors);
794 pos = XCALLOC (base_t, nentries);
795 table = XCALLOC (base_t, table_size);
ea99527d 796 conflict_table = XCALLOC (unsigned int, table_size);
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797 check = XCALLOC (base_t, table_size);
798
799 lowzero = 0;
800 high = 0;
801
802 for (i = 0; i < nvectors; i++)
803 base[i] = BASE_MIN;
804
805 for (i = 0; i < (int) table_size; i++)
806 check[i] = -1;
807
808 for (i = 0; i < nentries; i++)
809 {
810 state_number_t state = matching_state (i);
811 base_t place;
812
813 if (state < 0)
814 /* A new set of state actions, or a nonterminal. */
815 place = pack_vector (i);
816 else
817 /* Action of I were already coded for STATE. */
818 place = base[state];
819
820 pos[i] = place;
821 base[order[i]] = place;
822 }
823
824 /* Use the greatest possible negative infinites. */
825 base_ninf = table_ninf_remap (base, nvectors, BASE_MIN);
826 table_ninf = table_ninf_remap (table, high + 1, ACTION_MIN);
827
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828 free (pos);
829}
830
831\f
832
833/*-----------------------------------------------------------------.
834| Compute and output yydefact, yydefgoto, yypact, yypgoto, yytable |
835| and yycheck. |
836`-----------------------------------------------------------------*/
837
838void
839tables_generate (void)
840{
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841 int i;
842
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843 /* That's a poor way to make sure the sizes are properly corelated,
844 in particular the signedness is not taking into account, but it's
845 not useless. */
846 assert (sizeof (nvectors) >= sizeof (nstates));
847 assert (sizeof (nvectors) >= sizeof (nvars));
848
849 nvectors = state_number_as_int (nstates) + nvars;
850
851 froms = XCALLOC (base_t *, nvectors);
852 tos = XCALLOC (base_t *, nvectors);
853 conflict_tos = XCALLOC (unsigned int *, nvectors);
854 tally = XCALLOC (short, nvectors);
855 width = XCALLOC (base_t, nvectors);
856
857 token_actions ();
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858
859 goto_actions ();
860 XFREE (goto_map + ntokens);
861 XFREE (from_state);
862 XFREE (to_state);
863
864 order = XCALLOC (vector_number_t, nvectors);
865 sort_actions ();
866 pack_table ();
867 free (order);
868
869 free (tally);
870 free (width);
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871
872 for (i = 0; i < nvectors; i++)
873 {
874 XFREE (froms[i]);
875 XFREE (tos[i]);
876 XFREE (conflict_tos[i]);
877 }
878
879 free (froms);
880 free (tos);
881 free (conflict_tos);
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882}
883
884
885/*-------------------------.
886| Free the parser tables. |
887`-------------------------*/
888
889void
890tables_free (void)
891{
892 free (base);
893 free (conflict_table);
894 free (conflict_list);
895 free (table);
896 free (check);
897 free (yydefgoto);
898 free (yydefact);
899}