src/gram.c

   1 /* Allocate input grammar variables for bison,
   2    Copyright 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 "gram.h"
  24 #include "symtab.h"
  25 #include "reader.h"
  26
  27 /* comments for these variables are in gram.h  */
  28
  29 int nitems;
  30 int nrules;
  31 int nsyms;
  32 int ntokens;
  33 int nvars;
  34
  35 short *ritem = NULL;
  36 int nritems;
  37
  38 rule_t *rules = NULL;
  39
  40 struct bucket **symbols = NULL;
  41 short *token_translations = NULL;
  42
  43 int start_symbol;
  44
  45 int max_user_token_number;
  46
  47 int semantic_parser;
  48
  49 int pure_parser;
  50
  51 int error_token_number;
  52
  53
  54 /*--------------------------------------.
  55 | Return the number of symbols in RHS.  |
  56 `--------------------------------------*/
  57
  58 int
  59 rule_rhs_length (rule_t *rule)
  60 {
  61   int res = 0;
  62   short *rhsp;
  63   for (rhsp = rule->rhs; *rhsp >= 0; ++rhsp)
  64     ++res;
  65   return res;
  66 }
  67
  68
  69 /*------------------------.
  70 | Dump RITEM for traces.  |
  71 `------------------------*/
  72
  73 void
  74 ritem_print (FILE *out)
  75 {
  76   int i;
  77   fputs ("RITEM\n", out);
  78   for (i = 0; i < nritems; ++i)
  79     if (ritem[i] >= 0)
  80       fprintf (out, "  %s", symbols[ritem[i]]->tag);
  81     else
  82       fprintf (out, "  (rule %d)\n", -ritem[i] - 1);
  83   fputs ("\n\n", out);
  84 }
  85
  86
  87 /*------------------------------------------.
  88 | Return the size of the longest rule RHS.  |
  89 `------------------------------------------*/
  90
  91 size_t
  92 ritem_longest_rhs (void)
  93 {
  94   int max = 0;
  95   int i;
  96
  97   for (i = 1; i < nrules + 1; ++i)
  98     {
  99       int length = rule_rhs_length (&rules[i]);
 100       if (length > max)
 101         max = length;
 102     }
 103
 104   return max;
 105 }