1 /* Allocate input grammar variables for Bison.
2
3 Copyright (C) 1984, 1986, 1989, 2001-2003, 2005-2015, 2018-2021 Free
4 Software 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 <https://www.gnu.org/licenses/>. */
20
21 #include <config.h>
22 #include "system.h"
23
24 #include "complain.h"
25 #include "getargs.h"
26 #include "glyphs.h"
27 #include "gram.h"
28 #include "print-xml.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 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 nnterms = 0;
45
46 symbol_number *token_translations = NULL;
47
48 int max_code = 256;
49
50 int required_version = 0;
51
52 void
53 item_print (item_number *item, rule const *previous_rule, FILE *out)
54 {
55 rule const *r = item_rule (item);
56 rule_lhs_print (r, previous_rule ? previous_rule->lhs : NULL, out);
57
58 if (0 <= *r->rhs)
59 {
60 // Non-empty rhs.
61 for (item_number *sp = r->rhs; sp < item; sp++)
62 fprintf (out, " %s", symbols[*sp]->tag);
63 fprintf (out, " %s", dot);
64 for (item_number *sp = item; 0 <= *sp; ++sp)
65 fprintf (out, " %s", symbols[*sp]->tag);
66 }
67 else
68 fprintf (out, " %s %s", empty, dot);
69 }
70
71
72 bool
73 rule_useful_in_grammar_p (rule const *r)
74 {
75 return r->number < nrules;
76 }
77
78 bool
79 rule_useless_in_grammar_p (rule const *r)
80 {
81 return !rule_useful_in_grammar_p (r);
82 }
83
84 bool
85 rule_useless_in_parser_p (rule const *r)
86 {
87 return !r->useful && rule_useful_in_grammar_p (r);
88 }
89
90 bool
91 rule_useless_chain_p (rule const *r)
92 {
93 return rule_rhs_length (r) == 1 && !r->action;
94 }
95
96 void
97 rule_lhs_print (rule const *r, sym_content const *previous_lhs, FILE *out)
98 {
99 fprintf (out, " %3d ", r->number);
100 if (previous_lhs != r->lhs)
101 fprintf (out, "%s:", r->lhs->symbol->tag);
102 else
103 fprintf (out, "%*s|", (int) strlen (previous_lhs->symbol->tag), "");
104 }
105
106 void
107 rule_lhs_print_xml (rule const *r, FILE *out, int level)
108 {
109 xml_printf (out, level, "<lhs>%s</lhs>", r->lhs->symbol->tag);
110 }
111
112 size_t
113 rule_rhs_length (rule const *r)
114 {
115 size_t res = 0;
116 for (item_number *rhsp = r->rhs; 0 <= *rhsp; ++rhsp)
117 ++res;
118 return res;
119 }
120
121 void
122 rule_rhs_print (rule const *r, FILE *out)
123 {
124 if (0 <= *r->rhs)
125 for (item_number *rhsp = r->rhs; 0 <= *rhsp; ++rhsp)
126 fprintf (out, " %s", symbols[*rhsp]->tag);
127 else
128 fprintf (out, " %s", empty);
129 }
130
131 static void
132 rule_rhs_print_xml (rule const *r, FILE *out, int level)
133 {
134 if (*r->rhs >= 0)
135 {
136 xml_puts (out, level, "<rhs>");
137 for (item_number *rhsp = r->rhs; 0 <= *rhsp; ++rhsp)
138 xml_printf (out, level + 1, "<symbol>%s</symbol>",
139 xml_escape (symbols[*rhsp]->tag));
140 xml_puts (out, level, "</rhs>");
141 }
142 else
143 {
144 xml_puts (out, level, "<rhs>");
145 xml_puts (out, level + 1, "<empty/>");
146 xml_puts (out, level, "</rhs>");
147 }
148 }
149
150 void
151 rule_print (rule const *r, rule const *prev_rule, FILE *out)
152 {
153 rule_lhs_print (r, prev_rule ? prev_rule->lhs : NULL, out);
154 rule_rhs_print (r, out);
155 }
156
157 void
158 ritem_print (FILE *out)
159 {
160 fputs ("RITEM\n", out);
161 bool first = true;
162 for (int i = 0; i < nritems; ++i)
163 {
164 if (first)
165 {
166 fprintf (out, " %d: ", i);
167 first = false;
168 }
169 if (ritem[i] >= 0)
170 fprintf (out, " %s", symbols[ritem[i]]->tag);
171 else
172 {
173 fprintf (out, " (rule %d)\n", item_number_as_rule_number (ritem[i]));
174 first = true;
175 }
176 }
177 fputs ("\n\n", out);
178 }
179
180 size_t
181 ritem_longest_rhs (void)
182 {
183 int max = 0;
184 for (rule_number r = 0; r < nrules; ++r)
185 {
186 size_t length = rule_rhs_length (&rules[r]);
187 if (length > max)
188 max = length;
189 }
190
191 return max;
192 }
193
194 void
195 grammar_rules_partial_print (FILE *out, const char *title,
196 rule_filter filter)
197 {
198 bool first = true;
199 rule *previous_rule = NULL;
200
201 /* rule # : LHS -> RHS */
202 for (rule_number r = 0; r < nrules + nuseless_productions; r++)
203 {
204 if (filter && !filter (&rules[r]))
205 continue;
206 if (first)
207 fprintf (out, "%s\n\n", title);
208 else if (previous_rule && previous_rule->lhs != rules[r].lhs)
209 putc ('\n', out);
210 first = false;
211 rule_print (&rules[r], previous_rule, out);
212 putc ('\n', out);
213 previous_rule = &rules[r];
214 }
215 if (!first)
216 fputs ("\n\n", out);
217 }
218
219 void
220 grammar_rules_print (FILE *out)
221 {
222 grammar_rules_partial_print (out, _("Grammar"), rule_useful_in_grammar_p);
223 }
224
225 void
226 grammar_rules_print_xml (FILE *out, int level)
227 {
228 bool first = true;
229
230 for (rule_number r = 0; r < nrules + nuseless_productions; r++)
231 {
232 if (first)
233 xml_puts (out, level + 1, "<rules>");
234 first = false;
235 {
236 char const *usefulness
237 = rule_useless_in_grammar_p (&rules[r]) ? "useless-in-grammar"
238 : rule_useless_in_parser_p (&rules[r]) ? "useless-in-parser"
239 : "useful";
240 xml_indent (out, level + 2);
241 fprintf (out, "<rule number=\"%d\" usefulness=\"%s\"",
242 rules[r].number, usefulness);
243 if (rules[r].precsym)
244 fprintf (out, " percent_prec=\"%s\"",
245 xml_escape (rules[r].precsym->symbol->tag));
246 fputs (">\n", out);
247 }
248 rule_lhs_print_xml (&rules[r], out, level + 3);
249 rule_rhs_print_xml (&rules[r], out, level + 3);
250 xml_puts (out, level + 2, "</rule>");
251 }
252 if (!first)
253 xml_puts (out, level + 1, "</rules>");
254 else
255 xml_puts (out, level + 1, "<rules/>");
256 }
257
258 static void
259 section (FILE *out, const char *s)
260 {
261 fprintf (out, "%s\n", s);
262 for (int i = strlen (s); 0 < i; --i)
263 putc ('-', out);
264 putc ('\n', out);
265 putc ('\n', out);
266 }
267
268 void
269 grammar_dump (FILE *out, const char *title)
270 {
271 fprintf (out, "%s\n\n", title);
272 fprintf (out,
273 "ntokens = %d, nnterms = %d, nsyms = %d, nrules = %d, nritems = %d\n\n",
274 ntokens, nnterms, nsyms, nrules, nritems);
275
276 section (out, "Tokens");
277 {
278 fprintf (out, "Value Sprec Sassoc Tag\n");
279
280 for (symbol_number i = 0; i < ntokens; i++)
281 fprintf (out, "%5d %5d %5d %s\n",
282 i,
283 symbols[i]->content->prec, symbols[i]->content->assoc,
284 symbols[i]->tag);
285 fprintf (out, "\n\n");
286 }
287
288 section (out, "Nonterminals");
289 {
290 fprintf (out, "Value Tag\n");
291
292 for (symbol_number i = ntokens; i < nsyms; i++)
293 fprintf (out, "%5d %s\n",
294 i, symbols[i]->tag);
295 fprintf (out, "\n\n");
296 }
297
298 section (out, "Rules");
299 {
300 fprintf (out,
301 "Num (Prec, Assoc, Useful, UselessChain) Lhs"
302 " -> (Ritem Range) Rhs\n");
303 for (rule_number i = 0; i < nrules + nuseless_productions; ++i)
304 {
305 rule const *rule_i = &rules[i];
306 int const rhs_itemno = rule_i->rhs - ritem;
307 int length = rule_rhs_length (rule_i);
308 aver (item_number_as_rule_number (rule_i->rhs[length]) == i);
309 fprintf (out, "%3d (%2d, %2d, %2s, %2s) %2d -> (%2u-%2u)",
310 i,
311 rule_i->prec ? rule_i->prec->prec : 0,
312 rule_i->prec ? rule_i->prec->assoc : 0,
313 rule_i->useful ? "t" : "f",
314 rule_useless_chain_p (rule_i) ? "t" : "f",
315 rule_i->lhs->number,
316 rhs_itemno, rhs_itemno + length - 1);
317 /* Dumped the RHS. */
318 for (item_number *rhsp = rule_i->rhs; 0 <= *rhsp; ++rhsp)
319 fprintf (out, " %3d", *rhsp);
320 putc ('\n', out);
321 }
322 }
323 fprintf (out, "\n\n");
324
325 section (out, "Rules interpreted");
326 for (rule_number r = 0; r < nrules + nuseless_productions; ++r)
327 {
328 fprintf (out, "%-5d %s:", r, rules[r].lhs->symbol->tag);
329 rule_rhs_print (&rules[r], out);
330 putc ('\n', out);
331 }
332 fprintf (out, "\n\n");
333 }
334
335 void
336 grammar_rules_useless_report (const char *message)
337 {
338 for (rule_number r = 0; r < nrules; ++r)
339 /* Don't complain about rules whose LHS is useless, we already
340 complained about it. */
341 if (!reduce_nonterminal_useless_in_grammar (rules[r].lhs)
342 && !rules[r].useful)
343 complain (&rules[r].location, Wother, "%s", message);
344 }
345
346 void
347 grammar_free (void)
348 {
349 if (ritem)
350 free (ritem - 1);
351 free (rules);
352 free (token_translations);
353 /* Free the symbol table data structure. */
354 symbols_free ();
355 free_merger_functions ();
356 }