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 | Print this RULE's RHS on OUT.  |
  66 `-------------------------------*/
  67
  68 void
  69 rule_rhs_print (rule_t *rule, FILE *out)
  70 {
  71   if (*rule->rhs >= 0)
  72     {
  73       item_number_t *r;
  74       for (r = rule->rhs; *r >= 0; r++)
  75         fprintf (out, " %s", symbol_tag_get (symbols[*r]));
  76       fputc ('\n', out);
  77     }
  78   else
  79     {
  80       fprintf (out, " /* %s */\n", _("empty"));
  81     }
  82 }
  83
  84
  85 /*-------------------------.
  86 | Print this RULE on OUT.  |
  87 `-------------------------*/
  88
  89 void
  90 rule_print (rule_t *rule, FILE *out)
  91 {
  92   fprintf (out, "%s:", symbol_tag_get (rule->lhs));
  93   rule_rhs_print (rule, out);
  94 }
  95
  96
  97 /*------------------------.
  98 | Dump RITEM for traces.  |
  99 `------------------------*/
 100
 101 void
 102 ritem_print (FILE *out)
 103 {
 104   unsigned int i;
 105   fputs ("RITEM\n", out);
 106   for (i = 0; i < nritems; ++i)
 107     if (ritem[i] >= 0)
 108       fprintf (out, "  %s", symbol_tag_get (symbols[ritem[i]]));
 109     else
 110       fprintf (out, "  (rule %d)\n", -ritem[i] - 1);
 111   fputs ("\n\n", out);
 112 }
 113
 114
 115 /*------------------------------------------.
 116 | Return the size of the longest rule RHS.  |
 117 `------------------------------------------*/
 118
 119 size_t
 120 ritem_longest_rhs (void)
 121 {
 122   int max = 0;
 123   int i;
 124
 125   for (i = 1; i < nrules + 1; ++i)
 126     {
 127       int length = rule_rhs_length (&rules[i]);
 128       if (length > max)
 129         max = length;
 130     }
 131
 132   return max;
 133 }
 134
 135
 136 /*----------------------------------------------------------------.
 137 | Print the grammar's rules numbers from BEGIN (inclusive) to END |
 138 | (exclusive) on OUT under TITLE.                                 |
 139 `----------------------------------------------------------------*/
 140
 141 static inline void
 142 blanks_print (unsigned n, FILE *out)
 143 {
 144   for (/* Nothing*/; n > 0; --n)
 145     fputc (' ', out);
 146 }
 147
 148 void
 149 grammar_rules_partial_print (FILE *out, const char *title,
 150                              int begin, int end)
 151 {
 152   int r;
 153   symbol_t *last_lhs = NULL;
 154
 155   /* rule # : LHS -> RHS */
 156   fprintf (out, "%s\n\n", title);
 157   for (r = begin; r < end; r++)
 158     {
 159       if (last_lhs && last_lhs != rules[r].lhs)
 160         fputc ('\n', out);
 161
 162       fprintf (out, "  %3d ", r - 1);
 163       if (last_lhs != rules[r].lhs)
 164         {
 165           last_lhs = rules[r].lhs;
 166           fprintf (out, "%s:", symbol_tag_get (last_lhs));
 167         }
 168       else
 169         {
 170           blanks_print (strlen (symbol_tag_get (last_lhs)), out);
 171           fputc ('|', out);
 172         }
 173       rule_rhs_print (&rules[r], out);
 174     }
 175   fputs ("\n\n", out);
 176 }
 177
 178
 179 /*------------------------------------------.
 180 | Print the grammar's useful rules on OUT.  |
 181 `------------------------------------------*/
 182
 183 void
 184 grammar_rules_print (FILE *out)
 185 {
 186   grammar_rules_partial_print (out, _("Grammar"), 1, nrules + 1);
 187 }
 188
 189
 190 /*-------------------.
 191 | Dump the grammar.  |
 192 `-------------------*/
 193
 194 void
 195 grammar_dump (FILE *out, const char *title)
 196 {
 197   int i;
 198   item_number_t *r;
 199
 200   fprintf (out, "%s\n\n", title);
 201   fprintf (out,
 202            "ntokens = %d, nvars = %d, nsyms = %d, nrules = %d, nritems = %d\n\n",
 203            ntokens, nvars, nsyms, nrules, nritems);
 204   fprintf (out, "Variables\n---------\n\n");
 205   fprintf (out, "Value  Sprec  Sassoc  Tag\n");
 206   for (i = ntokens; i < nsyms; i++)
 207     fprintf (out, "%5d  %5d   %5d  %s\n",
 208              i,
 209              symbols[i]->prec, symbols[i]->assoc,
 210              symbol_tag_get (symbols[i]));
 211   fprintf (out, "\n\n");
 212   fprintf (out, "Rules\n-----\n\n");
 213   fprintf (out, "Num (Prec, Assoc, Useful, Ritem Range) Lhs -> Rhs (Ritem range) [Num]\n");
 214   for (i = 1; i < nrules + nuseless_productions + 1; i++)
 215     {
 216       int rhs_count = 0;
 217       /* Find the last RHS index in ritems. */
 218       for (r = rules[i].rhs; *r >= 0; ++r)
 219         ++rhs_count;
 220       fprintf (out, "%3d (%2d, %2d, %2d, %2d-%2d)   %2d ->",
 221                i - 1,
 222                rules[i].prec ? rules[i].prec->prec : 0,
 223                rules[i].prec ? rules[i].prec->assoc : 0,
 224                rules[i].useful,
 225                rules[i].rhs - ritem,
 226                rules[i].rhs - ritem + rhs_count - 1,
 227                rules[i].lhs->number);
 228       /* Dumped the RHS. */
 229       for (r = rules[i].rhs; *r >= 0; r++)
 230         fprintf (out, " %3d", *r);
 231       fprintf (out, "  [%d]\n", -(*r) - 1);
 232     }
 233   fprintf (out, "\n\n");
 234   fprintf (out, "Rules interpreted\n-----------------\n\n");
 235   for (i = 1; i < nrules + nuseless_productions + 1; i++)
 236     {
 237       fprintf (out, "%-5d  ", i);
 238       rule_print (&rules[i], out);
 239     }
 240   fprintf (out, "\n\n");
 241 }
 242
 243
 244 void
 245 grammar_free (void)
 246 {
 247   XFREE (ritem);
 248   free (rules + 1);
 249   XFREE (token_translations);
 250   /* Free the symbol table data structure.  */
 251   symbols_free ();
 252 }