src/gram.c

   1 /* Allocate input grammar variables for Bison.
   2
   3    Copyright (C) 1984, 1986, 1989, 2001-2003, 2005-2011 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 <quotearg.h>
  25
  26 #include "complain.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 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 bool
  51 rule_useful_in_grammar_p (rule *r)
  52 {
  53   return r->number < nrules;
  54 }
  55
  56 bool
  57 rule_useless_in_grammar_p (rule *r)
  58 {
  59   return !rule_useful_in_grammar_p (r);
  60 }
  61
  62 bool
  63 rule_useless_in_parser_p (rule *r)
  64 {
  65   return !r->useful && rule_useful_in_grammar_p (r);
  66 }
  67
  68 void
  69 rule_lhs_print (rule *r, symbol *previous_lhs, FILE *out)
  70 {
  71   fprintf (out, "  %3d ", r->number);
  72   if (previous_lhs != r->lhs)
  73     {
  74       fprintf (out, "%s:", r->lhs->tag);
  75     }
  76   else
  77     {
  78       int n;
  79       for (n = strlen (previous_lhs->tag); n > 0; --n)
  80         fputc (' ', out);
  81       fputc ('|', out);
  82     }
  83 }
  84
  85 void
  86 rule_lhs_print_xml (rule *r, FILE *out, int level)
  87 {
  88   xml_printf (out, level, "<lhs>%s</lhs>", r->lhs->tag);
  89 }
  90
  91 size_t
  92 rule_rhs_length (rule *r)
  93 {
  94   size_t res = 0;
  95   item_number *rhsp;
  96   for (rhsp = r->rhs; *rhsp >= 0; ++rhsp)
  97     ++res;
  98   return res;
  99 }
 100
 101 void
 102 rule_rhs_print (rule *r, FILE *out)
 103 {
 104   if (*r->rhs >= 0)
 105     {
 106       item_number *rp;
 107       for (rp = r->rhs; *rp >= 0; rp++)
 108         fprintf (out, " %s", symbols[*rp]->tag);
 109       fputc ('\n', out);
 110     }
 111   else
 112     {
 113       fprintf (out, " /* %s */\n", _("empty"));
 114     }
 115 }
 116
 117 static void
 118 rule_rhs_print_xml (rule *r, FILE *out, int level)
 119 {
 120   if (*r->rhs >= 0)
 121     {
 122       item_number *rp;
 123       xml_puts (out, level, "<rhs>");
 124       for (rp = r->rhs; *rp >= 0; rp++)
 125         xml_printf (out, level + 1, "<symbol>%s</symbol>",
 126                     xml_escape (symbols[*rp]->tag));
 127       xml_puts (out, level, "</rhs>");
 128     }
 129   else
 130     {
 131       xml_puts (out, level, "<rhs>");
 132       xml_puts (out, level + 1, "<empty/>");
 133       xml_puts (out, level, "</rhs>");
 134     }
 135 }
 136
 137 void
 138 rule_print (rule *r, FILE *out)
 139 {
 140   fprintf (out, "%s:", r->lhs->tag);
 141   rule_rhs_print (r, out);
 142 }
 143
 144 void
 145 ritem_print (FILE *out)
 146 {
 147   unsigned int i;
 148   fputs ("RITEM\n", out);
 149   for (i = 0; i < nritems; ++i)
 150     if (ritem[i] >= 0)
 151       fprintf (out, "  %s", symbols[ritem[i]]->tag);
 152     else
 153       fprintf (out, "  (rule %d)\n", item_number_as_rule_number (ritem[i]));
 154   fputs ("\n\n", out);
 155 }
 156
 157 size_t
 158 ritem_longest_rhs (void)
 159 {
 160   int max = 0;
 161   rule_number r;
 162
 163   for (r = 0; r < nrules; ++r)
 164     {
 165       int length = rule_rhs_length (&rules[r]);
 166       if (length > max)
 167         max = length;
 168     }
 169
 170   return max;
 171 }
 172
 173 void
 174 grammar_rules_partial_print (FILE *out, const char *title,
 175                              rule_filter filter)
 176 {
 177   rule_number r;
 178   bool first = true;
 179   symbol *previous_lhs = NULL;
 180
 181   /* rule # : LHS -> RHS */
 182   for (r = 0; r < nrules + nuseless_productions; r++)
 183     {
 184       if (filter && !filter (&rules[r]))
 185         continue;
 186       if (first)
 187         fprintf (out, "%s\n\n", title);
 188       else if (previous_lhs && previous_lhs != rules[r].lhs)
 189         fputc ('\n', out);
 190       first = false;
 191       rule_lhs_print (&rules[r], previous_lhs, out);
 192       rule_rhs_print (&rules[r], out);
 193       previous_lhs = rules[r].lhs;
 194     }
 195   if (!first)
 196     fputs ("\n\n", out);
 197 }
 198
 199 void
 200 grammar_rules_print (FILE *out)
 201 {
 202   grammar_rules_partial_print (out, _("Grammar"), rule_useful_in_grammar_p);
 203 }
 204
 205 void
 206 grammar_rules_print_xml (FILE *out, int level)
 207 {
 208   rule_number r;
 209   bool first = true;
 210
 211   for (r = 0; r < nrules + nuseless_productions; r++)
 212     {
 213       if (first)
 214         xml_puts (out, level + 1, "<rules>");
 215       first = false;
 216       {
 217         char const *usefulness;
 218         if (rule_useless_in_grammar_p (&rules[r]))
 219           usefulness = "useless-in-grammar";
 220         else if (rule_useless_in_parser_p (&rules[r]))
 221           usefulness = "useless-in-parser";
 222         else
 223           usefulness = "useful";
 224         xml_indent (out, level + 2);
 225         fprintf (out, "<rule number=\"%d\" usefulness=\"%s\"",
 226                  rules[r].number, usefulness);
 227         if (rules[r].precsym)
 228           fprintf (out, " percent_prec=\"%s\"",
 229                    xml_escape (rules[r].precsym->tag));
 230         fputs (">\n", out);
 231       }
 232       rule_lhs_print_xml (&rules[r], out, level + 3);
 233       rule_rhs_print_xml (&rules[r], out, level + 3);
 234       xml_puts (out, level + 2, "</rule>");
 235     }
 236   if (!first)
 237     xml_puts (out, level + 1, "</rules>");
 238   else
 239    xml_puts (out, level + 1, "<rules/>");
 240 }
 241
 242 void
 243 grammar_dump (FILE *out, const char *title)
 244 {
 245   fprintf (out, "%s\n\n", title);
 246   fprintf (out,
 247            "ntokens = %d, nvars = %d, nsyms = %d, nrules = %d, nritems = %d\n\n",
 248            ntokens, nvars, nsyms, nrules, nritems);
 249
 250
 251   fprintf (out, "Variables\n---------\n\n");
 252   {
 253     symbol_number i;
 254     fprintf (out, "Value  Sprec  Sassoc  Tag\n");
 255
 256     for (i = ntokens; i < nsyms; i++)
 257       fprintf (out, "%5d  %5d   %5d  %s\n",
 258                i,
 259                symbols[i]->prec, symbols[i]->assoc,
 260                symbols[i]->tag);
 261     fprintf (out, "\n\n");
 262   }
 263
 264   fprintf (out, "Rules\n-----\n\n");
 265   {
 266     rule_number i;
 267     fprintf (out, "Num (Prec, Assoc, Useful, Ritem Range) Lhs -> Rhs (Ritem range) [Num]\n");
 268     for (i = 0; i < nrules + nuseless_productions; i++)
 269       {
 270         rule *rule_i = &rules[i];
 271         item_number *rp = NULL;
 272         unsigned int rhs_itemno = rule_i->rhs - ritem;
 273         unsigned int rhs_count = 0;
 274         /* Find the last RHS index in ritems. */
 275         for (rp = rule_i->rhs; *rp >= 0; ++rp)
 276           ++rhs_count;
 277         fprintf (out, "%3d (%2d, %2d, %2d, %2u-%2u)   %2d ->",
 278                  i,
 279                  rule_i->prec ? rule_i->prec->prec : 0,
 280                  rule_i->prec ? rule_i->prec->assoc : 0,
 281                  rule_i->useful,
 282                  rhs_itemno,
 283                  rhs_itemno + rhs_count - 1,
 284                  rule_i->lhs->number);
 285         /* Dumped the RHS. */
 286         for (rp = rule_i->rhs; *rp >= 0; rp++)
 287           fprintf (out, " %3d", *rp);
 288         fprintf (out, "  [%d]\n", item_number_as_rule_number (*rp));
 289       }
 290   }
 291   fprintf (out, "\n\n");
 292
 293   fprintf (out, "Rules interpreted\n-----------------\n\n");
 294   {
 295     rule_number r;
 296     for (r = 0; r < nrules + nuseless_productions; r++)
 297       {
 298         fprintf (out, "%-5d  ", r);
 299         rule_print (&rules[r], out);
 300       }
 301   }
 302   fprintf (out, "\n\n");
 303 }
 304
 305 void
 306 grammar_rules_useless_report (const char *message)
 307 {
 308   rule_number r;
 309   for (r = 0; r < nrules ; ++r)
 310     if (!rules[r].useful)
 311       {
 312         warn_at (rules[r].location, "%s: ", message);
 313         rule_print (&rules[r], stderr);
 314         fflush (stderr);
 315       }
 316 }
 317
 318 void
 319 grammar_free (void)
 320 {
 321   if (ritem)
 322     free (ritem - 1);
 323   free (rules);
 324   free (token_translations);
 325   /* Free the symbol table data structure.  */
 326   symbols_free ();
 327   free_merger_functions ();
 328 }