src/gram.c

   1 /* Allocate input grammar variables for bison,
   2    Copyright (C) 1984, 1986, 1989, 2001, 2002 Free Software Foundation, Inc.
   3
   4    This file is part of Bison, the GNU Compiler Compiler.
   5
   6    Bison is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2, or (at your option)
   9    any later version.
  10
  11    Bison is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with Bison; see the file COPYING.  If not, write to
  18    the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21
  22 #include "system.h"
  23 #include "quotearg.h"
  24 #include "symtab.h"
  25 #include "gram.h"
  26 #include "reduce.h"
  27 #include "reader.h"
  28
  29 /* comments for these variables are in gram.h  */
  30
  31 item_number_t *ritem = NULL;
  32 int nritems = 0;
  33
  34 rule_t *rules = NULL;
  35 int nrules = 0;
  36
  37 symbol_t **symbols = NULL;
  38 int nsyms = 0;
  39 int ntokens = 1;
  40 int nvars = 0;
  41
  42 token_number_t *token_translations = NULL;
  43
  44 token_number_t start_symbol = 0;
  45
  46 int max_user_token_number = 256;
  47
  48 int pure_parser = 0;
  49
  50
  51 /*--------------------------------------.
  52 | Return the number of symbols in RHS.  |
  53 `--------------------------------------*/
  54
  55 int
  56 rule_rhs_length (rule_t *rule)
  57 {
  58   int res = 0;
  59   item_number_t *rhsp;
  60   for (rhsp = rule->rhs; *rhsp >= 0; ++rhsp)
  61     ++res;
  62   return res;
  63 }
  64
  65
  66 /*------------------------.
  67 | Dump RITEM for traces.  |
  68 `------------------------*/
  69
  70 void
  71 ritem_print (FILE *out)
  72 {
  73   int i;
  74   fputs ("RITEM\n", out);
  75   for (i = 0; i < nritems; ++i)
  76     if (ritem[i] >= 0)
  77       fprintf (out, "  %s", quotearg_style (escape_quoting_style,
  78                                             symbols[ritem[i]]->tag));
  79     else
  80       fprintf (out, "  (rule %d)\n", -ritem[i] - 1);
  81   fputs ("\n\n", out);
  82 }
  83
  84
  85 /*------------------------------------------.
  86 | Return the size of the longest rule RHS.  |
  87 `------------------------------------------*/
  88
  89 size_t
  90 ritem_longest_rhs (void)
  91 {
  92   int max = 0;
  93   int i;
  94
  95   for (i = 1; i < nrules + 1; ++i)
  96     {
  97       int length = rule_rhs_length (&rules[i]);
  98       if (length > max)
  99         max = length;
 100     }
 101
 102   return max;
 103 }
 104
 105
 106 /*-------------------.
 107 | Dump the grammar.  |
 108 `-------------------*/
 109
 110 void
 111 grammar_dump (FILE *out, const char *title)
 112 {
 113   int i;
 114   item_number_t *r;
 115
 116   fprintf (out, "%s\n\n", title);
 117   fprintf (out,
 118            "ntokens = %d, nvars = %d, nsyms = %d, nrules = %d, nritems = %d\n\n",
 119            ntokens, nvars, nsyms, nrules, nritems);
 120   fprintf (out, "Variables\n---------\n\n");
 121   fprintf (out, "Value  Sprec  Sassoc  Tag\n");
 122   for (i = ntokens; i < nsyms; i++)
 123     fprintf (out, "%5d  %5d   %5d  %s\n",
 124              i,
 125              symbols[i]->prec, symbols[i]->assoc,
 126              quotearg_style (escape_quoting_style, symbols[i]->tag));
 127   fprintf (out, "\n\n");
 128   fprintf (out, "Rules\n-----\n\n");
 129   fprintf (out, "Num (Prec, Assoc, Useful, Ritem Range) Lhs -> Rhs (Ritem range) [Num]\n");
 130   for (i = 1; i < nrules + nuseless_productions + 1; i++)
 131     {
 132       int rhs_count = 0;
 133       /* Find the last RHS index in ritems. */
 134       for (r = rules[i].rhs; *r >= 0; ++r)
 135         ++rhs_count;
 136       fprintf (out, "%3d (%2d, %2d, %2d, %2d-%2d)   %2d ->",
 137                i - 1,
 138                rules[i].prec ? rules[i].prec->prec : 0,
 139                rules[i].prec ? rules[i].prec->assoc : 0,
 140                rules[i].useful,
 141                rules[i].rhs - ritem,
 142                rules[i].rhs - ritem + rhs_count - 1,
 143                rules[i].lhs->number);
 144       /* Dumped the RHS. */
 145       for (r = rules[i].rhs; *r >= 0; r++)
 146         fprintf (out, " %3d", *r);
 147       fprintf (out, "  [%d]\n", -(*r) - 1);
 148     }
 149   fprintf (out, "\n\n");
 150   fprintf (out, "Rules interpreted\n-----------------\n\n");
 151   for (i = 1; i < nrules + nuseless_productions + 1; i++)
 152     {
 153       fprintf (out, "%-5d  %s :",
 154                i, quotearg_style (escape_quoting_style, rules[i].lhs->tag));
 155       for (r = rules[i].rhs; *r >= 0; r++)
 156         fprintf (out, " %s",
 157                  quotearg_style (escape_quoting_style, symbols[*r]->tag));
 158       fputc ('\n', out);
 159     }
 160   fprintf (out, "\n\n");
 161 }
 162
 163
 164 void
 165 grammar_free (void)
 166 {
 167   XFREE (ritem);
 168   free (rules + 1);
 169   XFREE (token_translations);
 170   /* Free the symbol table data structure.  */
 171   symbols_free ();
 172 }