1 /* Allocate input grammar variables for Bison.
2
3 Copyright (C) 1984, 1986, 1989, 2001, 2002, 2003, 2005, 2006 Free
4 Software Foundation, Inc.
5
6 This file is part of Bison, the GNU Compiler Compiler.
7
8 Bison 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 2, or (at your option)
11 any later version.
12
13 Bison 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 Bison; see the file COPYING. If not, write to
20 the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
21 Boston, MA 02110-1301, USA. */
22
23 #include <config.h>
24 #include "system.h"
25
26 #include <quotearg.h>
27
28 #include "gram.h"
29 #include "reader.h"
30 #include "reduce.h"
31 #include "symtab.h"
32
33 /* Comments for these variables are in gram.h. */
34
35 item_number *ritem = NULL;
36 unsigned int nritems = 0;
37
38 rule *rules = NULL;
39 rule_number nrules = 0;
40
41 symbol **symbols = NULL;
42 int nsyms = 0;
43 int ntokens = 1;
44 int nvars = 0;
45
46 symbol_number *token_translations = NULL;
47
48 int max_user_token_number = 256;
49
50 /*--------------------------------------------------------------.
51 | Return true IFF the rule has a `number' smaller than NRULES. |
52 `--------------------------------------------------------------*/
53
54 bool
rule_useful_p(rule * r)55 rule_useful_p (rule *r)
56 {
57 return r->number < nrules;
58 }
59
60
61 /*-------------------------------------------------------------.
62 | Return true IFF the rule has a `number' higher than NRULES. |
63 `-------------------------------------------------------------*/
64
65 bool
rule_useless_p(rule * r)66 rule_useless_p (rule *r)
67 {
68 return !rule_useful_p (r);
69 }
70
71
72 /*--------------------------------------------------------------------.
73 | Return true IFF the rule is not flagged as useful *and* is useful. |
74 | In other words, it was discarded because of conflicts. |
75 `--------------------------------------------------------------------*/
76
77 bool
rule_never_reduced_p(rule * r)78 rule_never_reduced_p (rule *r)
79 {
80 return !r->useful && rule_useful_p (r);
81 }
82
83
84 /*----------------------------------------------------------------.
85 | Print this RULE's number and lhs on OUT. If a PREVIOUS_LHS was |
86 | already displayed (by a previous call for another rule), avoid |
87 | useless repetitions. |
88 `----------------------------------------------------------------*/
89
90 void
rule_lhs_print(rule * r,symbol * previous_lhs,FILE * out)91 rule_lhs_print (rule *r, symbol *previous_lhs, FILE *out)
92 {
93 fprintf (out, " %3d ", r->number);
94 if (previous_lhs != r->lhs)
95 {
96 fprintf (out, "%s:", r->lhs->tag);
97 }
98 else
99 {
100 int n;
101 for (n = strlen (previous_lhs->tag); n > 0; --n)
102 fputc (' ', out);
103 fputc ('|', out);
104 }
105 }
106
107
108 /*--------------------------------------.
109 | Return the number of symbols in RHS. |
110 `--------------------------------------*/
111
112 int
rule_rhs_length(rule * r)113 rule_rhs_length (rule *r)
114 {
115 int res = 0;
116 item_number *rhsp;
117 for (rhsp = r->rhs; *rhsp >= 0; ++rhsp)
118 ++res;
119 return res;
120 }
121
122
123 /*-------------------------------.
124 | Print this rule's RHS on OUT. |
125 `-------------------------------*/
126
127 void
rule_rhs_print(rule * r,FILE * out)128 rule_rhs_print (rule *r, FILE *out)
129 {
130 if (*r->rhs >= 0)
131 {
132 item_number *rp;
133 for (rp = r->rhs; *rp >= 0; rp++)
134 fprintf (out, " %s", symbols[*rp]->tag);
135 fputc ('\n', out);
136 }
137 else
138 {
139 fprintf (out, " /* %s */\n", _("empty"));
140 }
141 }
142
143
144 /*-------------------------.
145 | Print this rule on OUT. |
146 `-------------------------*/
147
148 void
rule_print(rule * r,FILE * out)149 rule_print (rule *r, FILE *out)
150 {
151 fprintf (out, "%s:", r->lhs->tag);
152 rule_rhs_print (r, out);
153 }
154
155
156 /*------------------------.
157 | Dump RITEM for traces. |
158 `------------------------*/
159
160 void
ritem_print(FILE * out)161 ritem_print (FILE *out)
162 {
163 unsigned int i;
164 fputs ("RITEM\n", out);
165 for (i = 0; i < nritems; ++i)
166 if (ritem[i] >= 0)
167 fprintf (out, " %s", symbols[ritem[i]]->tag);
168 else
169 fprintf (out, " (rule %d)\n", item_number_as_rule_number (ritem[i]));
170 fputs ("\n\n", out);
171 }
172
173
174 /*------------------------------------------.
175 | Return the size of the longest rule RHS. |
176 `------------------------------------------*/
177
178 size_t
ritem_longest_rhs(void)179 ritem_longest_rhs (void)
180 {
181 int max = 0;
182 rule_number r;
183
184 for (r = 0; r < nrules; ++r)
185 {
186 int length = rule_rhs_length (&rules[r]);
187 if (length > max)
188 max = length;
189 }
190
191 return max;
192 }
193
194
195 /*-----------------------------------------------------------------.
196 | Print the grammar's rules that match FILTER on OUT under TITLE. |
197 `-----------------------------------------------------------------*/
198
199 void
grammar_rules_partial_print(FILE * out,const char * title,rule_filter filter)200 grammar_rules_partial_print (FILE *out, const char *title,
201 rule_filter filter)
202 {
203 rule_number r;
204 bool first = true;
205 symbol *previous_lhs = NULL;
206
207 /* rule # : LHS -> RHS */
208 for (r = 0; r < nrules + nuseless_productions; r++)
209 {
210 if (filter && !filter (&rules[r]))
211 continue;
212 if (first)
213 fprintf (out, "%s\n\n", title);
214 else if (previous_lhs && previous_lhs != rules[r].lhs)
215 fputc ('\n', out);
216 first = false;
217 rule_lhs_print (&rules[r], previous_lhs, out);
218 rule_rhs_print (&rules[r], out);
219 previous_lhs = rules[r].lhs;
220 }
221 if (!first)
222 fputs ("\n\n", out);
223 }
224
225
226 /*------------------------------------------.
227 | Print the grammar's useful rules on OUT. |
228 `------------------------------------------*/
229
230 void
grammar_rules_print(FILE * out)231 grammar_rules_print (FILE *out)
232 {
233 grammar_rules_partial_print (out, _("Grammar"), rule_useful_p);
234 }
235
236
237 /*-------------------.
238 | Dump the grammar. |
239 `-------------------*/
240
241 void
grammar_dump(FILE * out,const char * title)242 grammar_dump (FILE *out, const char *title)
243 {
244 fprintf (out, "%s\n\n", title);
245 fprintf (out,
246 "ntokens = %d, nvars = %d, nsyms = %d, nrules = %d, nritems = %d\n\n",
247 ntokens, nvars, nsyms, nrules, nritems);
248
249
250 fprintf (out, "Variables\n---------\n\n");
251 {
252 symbol_number i;
253 fprintf (out, "Value Sprec Sassoc Tag\n");
254
255 for (i = ntokens; i < nsyms; i++)
256 fprintf (out, "%5d %5d %5d %s\n",
257 i,
258 symbols[i]->prec, symbols[i]->assoc,
259 symbols[i]->tag);
260 fprintf (out, "\n\n");
261 }
262
263 fprintf (out, "Rules\n-----\n\n");
264 {
265 rule_number i;
266 fprintf (out, "Num (Prec, Assoc, Useful, Ritem Range) Lhs -> Rhs (Ritem range) [Num]\n");
267 for (i = 0; i < nrules + nuseless_productions; i++)
268 {
269 rule *rule_i = &rules[i];
270 item_number *rp = NULL;
271 unsigned int rhs_itemno = rule_i->rhs - ritem;
272 unsigned int rhs_count = 0;
273 /* Find the last RHS index in ritems. */
274 for (rp = rule_i->rhs; *rp >= 0; ++rp)
275 ++rhs_count;
276 fprintf (out, "%3d (%2d, %2d, %2d, %2u-%2u) %2d ->",
277 i,
278 rule_i->prec ? rule_i->prec->prec : 0,
279 rule_i->prec ? rule_i->prec->assoc : 0,
280 rule_i->useful,
281 rhs_itemno,
282 rhs_itemno + rhs_count - 1,
283 rule_i->lhs->number);
284 /* Dumped the RHS. */
285 for (rp = rule_i->rhs; *rp >= 0; rp++)
286 fprintf (out, " %3d", *rp);
287 fprintf (out, " [%d]\n", item_number_as_rule_number (*rp));
288 }
289 }
290 fprintf (out, "\n\n");
291
292 fprintf (out, "Rules interpreted\n-----------------\n\n");
293 {
294 rule_number r;
295 for (r = 0; r < nrules + nuseless_productions; r++)
296 {
297 fprintf (out, "%-5d ", r);
298 rule_print (&rules[r], out);
299 }
300 }
301 fprintf (out, "\n\n");
302 }
303
304
305 /*------------------------------------------------------------------.
306 | Report on STDERR the rules that are not flagged USEFUL, using the |
307 | MESSAGE (which can be `useless rule' when invoked after grammar |
308 | reduction, or `never reduced' after conflicts were taken into |
309 | account). |
310 `------------------------------------------------------------------*/
311
312 void
grammar_rules_never_reduced_report(const char * message)313 grammar_rules_never_reduced_report (const char *message)
314 {
315 rule_number r;
316 for (r = 0; r < nrules ; ++r)
317 if (!rules[r].useful)
318 {
319 location_print (stderr, rules[r].location);
320 fprintf (stderr, ": %s: %s: ", _("warning"), message);
321 rule_print (&rules[r], stderr);
322 }
323 }
324
325 void
grammar_free(void)326 grammar_free (void)
327 {
328 if (ritem)
329 free (ritem - 1);
330 free (rules);
331 free (token_translations);
332 /* Free the symbol table data structure. */
333 symbols_free ();
334 free_merger_functions ();
335 }
336