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