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 unsigned 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 symbol_number_t *token_translations = NULL;
  43
  44 int max_user_token_number = 256;
  45
  46 int pure_parser = 0;
  47
  48
  49 /*--------------------------------------.
  50 | Return the number of symbols in RHS.  |
  51 `--------------------------------------*/
  52
  53 int
  54 rule_rhs_length (rule_t *rule)
  55 {
  56   int res = 0;
  57   item_number_t *rhsp;
  58   for (rhsp = rule->rhs; *rhsp >= 0; ++rhsp)
  59     ++res;
  60   return res;
  61 }
  62
  63
  64 /*------------------------.
  65 | Dump RITEM for traces.  |
  66 `------------------------*/
  67
  68 void
  69 ritem_print (FILE *out)
  70 {
  71   unsigned int i;
  72   fputs ("RITEM\n", out);
  73   for (i = 0; i < nritems; ++i)
  74     if (ritem[i] >= 0)
  75       fprintf (out, "  %s", quotearg_style (escape_quoting_style,
  76                                             symbols[ritem[i]]->tag));
  77     else
  78       fprintf (out, "  (rule %d)\n", -ritem[i] - 1);
  79   fputs ("\n\n", out);
  80 }
  81
  82
  83 /*------------------------------------------.
  84 | Return the size of the longest rule RHS.  |
  85 `------------------------------------------*/
  86
  87 size_t
  88 ritem_longest_rhs (void)
  89 {
  90   int max = 0;
  91   int i;
  92
  93   for (i = 1; i < nrules + 1; ++i)
  94     {
  95       int length = rule_rhs_length (&rules[i]);
  96       if (length > max)
  97         max = length;
  98     }
  99
 100   return max;
 101 }
 102
 103
 104 /*-------------------.
 105 | Dump the grammar.  |
 106 `-------------------*/
 107
 108 void
 109 grammar_dump (FILE *out, const char *title)
 110 {
 111   int i;
 112   item_number_t *r;
 113
 114   fprintf (out, "%s\n\n", title);
 115   fprintf (out,
 116            "ntokens = %d, nvars = %d, nsyms = %d, nrules = %d, nritems = %d\n\n",
 117            ntokens, nvars, nsyms, nrules, nritems);
 118   fprintf (out, "Variables\n---------\n\n");
 119   fprintf (out, "Value  Sprec  Sassoc  Tag\n");
 120   for (i = ntokens; i < nsyms; i++)
 121     fprintf (out, "%5d  %5d   %5d  %s\n",
 122              i,
 123              symbols[i]->prec, symbols[i]->assoc,
 124              quotearg_style (escape_quoting_style, symbols[i]->tag));
 125   fprintf (out, "\n\n");
 126   fprintf (out, "Rules\n-----\n\n");
 127   fprintf (out, "Num (Prec, Assoc, Useful, Ritem Range) Lhs -> Rhs (Ritem range) [Num]\n");
 128   for (i = 1; i < nrules + nuseless_productions + 1; i++)
 129     {
 130       int rhs_count = 0;
 131       /* Find the last RHS index in ritems. */
 132       for (r = rules[i].rhs; *r >= 0; ++r)
 133         ++rhs_count;
 134       fprintf (out, "%3d (%2d, %2d, %2d, %2d-%2d)   %2d ->",
 135                i - 1,
 136                rules[i].prec ? rules[i].prec->prec : 0,
 137                rules[i].prec ? rules[i].prec->assoc : 0,
 138                rules[i].useful,
 139                rules[i].rhs - ritem,
 140                rules[i].rhs - ritem + rhs_count - 1,
 141                rules[i].lhs->number);
 142       /* Dumped the RHS. */
 143       for (r = rules[i].rhs; *r >= 0; r++)
 144         fprintf (out, " %3d", *r);
 145       fprintf (out, "  [%d]\n", -(*r) - 1);
 146     }
 147   fprintf (out, "\n\n");
 148   fprintf (out, "Rules interpreted\n-----------------\n\n");
 149   for (i = 1; i < nrules + nuseless_productions + 1; i++)
 150     {
 151       fprintf (out, "%-5d  %s :",
 152                i, quotearg_style (escape_quoting_style, rules[i].lhs->tag));
 153       for (r = rules[i].rhs; *r >= 0; r++)
 154         fprintf (out, " %s",
 155                  quotearg_style (escape_quoting_style, symbols[*r]->tag));
 156       fputc ('\n', out);
 157     }
 158   fprintf (out, "\n\n");
 159 }
 160
 161
 162 void
 163 grammar_free (void)
 164 {
 165   XFREE (ritem);
 166   free (rules + 1);
 167   XFREE (token_translations);
 168   /* Free the symbol table data structure.  */
 169   symbols_free ();
 170 }