Do not let the scan-skel token buffer grow unboundedly in the usual case.

[bison.git] / src / gram.c

diff --git a/src/gram.c b/src/gram.c
index 35302616ace92a925b46d4bc0cd2c4c44409e31f..cf5a946db983e698269f6f2fa1aaa1800ecbc3ad 100644 (file)
--- a/src/gram.c
+++ b/src/gram.c
@@ -1,67 +1,338 @@
-/* Allocate input grammar variables for bison,
-   Copyright 1984, 1986, 1989, 2001 Free Software Foundation, Inc.
+/* Allocate input grammar variables for Bison.

 
 

-This file is part of Bison, the GNU Compiler Compiler.
+   Copyright (C) 1984, 1986, 1989, 2001, 2002 Free Software Foundation, Inc.

 
 

-Bison is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
-any later version.
+   This file is part of Bison, the GNU Compiler Compiler.

 
 

-Bison is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
+   Bison is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.

 
 

-You should have received a copy of the GNU General Public License
-along with Bison; see the file COPYING.  If not, write to
-the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA.  */
+   Bison is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with Bison; see the file COPYING.  If not, write to
+   the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */

 
 
 #include "system.h"
 
 
 #include "system.h"

+
+#include <quotearg.h>
+

 #include "gram.h"
 #include "reader.h"
 #include "gram.h"
 #include "reader.h"

+#include "reduce.h"
+#include "symtab.h"
+
+/* Comments for these variables are in gram.h.  */
+
+item_number *ritem = NULL;
+unsigned int nritems = 0;
+
+rule *rules = NULL;
+rule_number nrules = 0;

 
 

-void dummy PARAMS((void));
+symbol **symbols = NULL;
+int nsyms = 0;
+int ntokens = 1;
+int nvars = 0;

 
 

-/* comments for these variables are in gram.h  */
+symbol_number *token_translations = NULL;

 
 

-int nitems;
-int nrules;
-int nsyms;
-int ntokens;
-int nvars;
+int max_user_token_number = 256;

 
 

-short *ritem = NULL;
-rule_t *rule_table = NULL;
-short *rprec = NULL;
-short *rprecsym = NULL;
-short *sprec = NULL;
-short *rassoc = NULL;
-short *sassoc = NULL;
-short *token_translations = NULL;
-short *rline = NULL;
+int glr_parser = 0;
+int pure_parser = 0;
+
+
+/*--------------------------------------------------------------.
+| Return true IFF the rule has a `number' smaller than NRULES.  |
+`--------------------------------------------------------------*/
+
+bool
+rule_useful_p (rule *r)
+{
+  return r->number < nrules;
+}
+
+
+/*-------------------------------------------------------------.
+| Return true IFF the rule has a `number' higher than NRULES.  |
+`-------------------------------------------------------------*/
+
+bool
+rule_useless_p (rule *r)
+{
+  return r->number >= nrules;
+}
+
+
+/*--------------------------------------------------------------------.
+| Return true IFF the rule is not flagged as useful *and* is useful.  |
+| In other words, it was discarded because of conflicts.              |
+`--------------------------------------------------------------------*/
+
+bool
+rule_never_reduced_p (rule *r)
+{
+  return !r->useful && r->number < nrules;
+}

 
 

-int start_symbol;

 
 

-int max_user_token_number;
+/*----------------------------------------------------------------.
+| Print this RULE's number and lhs on OUT.  If a PREVIOUS_LHS was |
+| already displayed (by a previous call for another rule), avoid  |
+| useless repetitions.                                            |
+`----------------------------------------------------------------*/

 
 

-int semantic_parser;
+void
+rule_lhs_print (rule *r, symbol *previous_lhs, FILE *out)
+{
+  fprintf (out, "  %3d ", r->number);
+  if (previous_lhs != r->lhs)
+    {
+      fprintf (out, "%s:", r->lhs->tag);
+    }
+  else
+    {
+      int n;
+      for (n = strlen (previous_lhs->tag); n > 0; --n)
+       fputc (' ', out);
+      fputc ('|', out);
+    }
+}
+
+
+/*--------------------------------------.
+| Return the number of symbols in RHS.  |
+`--------------------------------------*/
+
+int
+rule_rhs_length (rule *r)
+{
+  int res = 0;
+  item_number *rhsp;
+  for (rhsp = r->rhs; *rhsp >= 0; ++rhsp)
+    ++res;
+  return res;
+}
+
+
+/*-------------------------------.
+| Print this rule's RHS on OUT.  |
+`-------------------------------*/
+
+void
+rule_rhs_print (rule *r, FILE *out)
+{
+  if (*r->rhs >= 0)
+    {
+      item_number *rp;
+      for (rp = r->rhs; *rp >= 0; rp++)
+       fprintf (out, " %s", symbols[*rp]->tag);
+      fputc ('\n', out);
+    }
+  else
+    {
+      fprintf (out, " /* %s */\n", _("empty"));
+    }
+}
+
+
+/*-------------------------.
+| Print this rule on OUT.  |
+`-------------------------*/
+
+void
+rule_print (rule *r, FILE *out)
+{
+  fprintf (out, "%s:", r->lhs->tag);
+  rule_rhs_print (r, out);
+}

 
 

-int pure_parser;

 
 

-int error_token_number;
+/*------------------------.
+| Dump RITEM for traces.  |
+`------------------------*/

 
 void
 ritem_print (FILE *out)
 {
 
 void
 ritem_print (FILE *out)
 {

-  int i;
+  unsigned int i;

   fputs ("RITEM\n", out);
   fputs ("RITEM\n", out);

-  for (i = 0; ritem[i]; ++i)
-    if (ritem[i] > 0)
-      fprintf (out, "  %s", tags[ritem[i]]);
+  for (i = 0; i < nritems; ++i)
+    if (ritem[i] >= 0)
+      fprintf (out, "  %s", symbols[ritem[i]]->tag);

     else
     else

-      fprintf (out, "  (rule %d)\n", -ritem[i]);
+      fprintf (out, "  (rule %d)\n", item_number_as_rule_number (ritem[i]));

   fputs ("\n\n", out);
 }
   fputs ("\n\n", out);
 }

+
+
+/*------------------------------------------.
+| Return the size of the longest rule RHS.  |
+`------------------------------------------*/
+
+size_t
+ritem_longest_rhs (void)
+{
+  int max = 0;
+  rule_number r;
+
+  for (r = 0; r < nrules; ++r)
+    {
+      int length = rule_rhs_length (&rules[r]);
+      if (length > max)
+       max = length;
+    }
+
+  return max;
+}
+
+
+/*-----------------------------------------------------------------.
+| Print the grammar's rules that match FILTER on OUT under TITLE.  |
+`-----------------------------------------------------------------*/
+
+void
+grammar_rules_partial_print (FILE *out, const char *title,
+                            rule_filter filter)
+{
+  int r;
+  bool first = true;
+  symbol *previous_lhs = NULL;
+
+  /* rule # : LHS -> RHS */
+  for (r = 0; r < nrules + nuseless_productions; r++)
+    {
+      if (filter && !filter (&rules[r]))
+       continue;
+      if (first)
+       fprintf (out, "%s\n\n", title);
+      else if (previous_lhs && previous_lhs != rules[r].lhs)
+       fputc ('\n', out);
+      first = false;
+      rule_lhs_print (&rules[r], previous_lhs, out);
+      rule_rhs_print (&rules[r], out);
+      previous_lhs = rules[r].lhs;
+    }
+  if (!first)
+    fputs ("\n\n", out);
+}
+
+
+/*------------------------------------------.
+| Print the grammar's useful rules on OUT.  |
+`------------------------------------------*/
+
+void
+grammar_rules_print (FILE *out)
+{
+  grammar_rules_partial_print (out, _("Grammar"), rule_useful_p);
+}
+
+
+/*-------------------.
+| Dump the grammar.  |
+`-------------------*/
+
+void
+grammar_dump (FILE *out, const char *title)
+{
+  fprintf (out, "%s\n\n", title);
+  fprintf (out,
+          "ntokens = %d, nvars = %d, nsyms = %d, nrules = %d, nritems = %d\n\n",
+          ntokens, nvars, nsyms, nrules, nritems);
+
+
+  fprintf (out, "Variables\n---------\n\n");
+  {
+    symbol_number i;
+    fprintf (out, "Value  Sprec  Sassoc  Tag\n");
+
+    for (i = ntokens; i < nsyms; i++)
+      fprintf (out, "%5d  %5d   %5d  %s\n",
+              i,
+              symbols[i]->prec, symbols[i]->assoc,
+              symbols[i]->tag);
+    fprintf (out, "\n\n");
+  }
+
+  fprintf (out, "Rules\n-----\n\n");
+  {
+    rule_number i;
+    fprintf (out, "Num (Prec, Assoc, Useful, Ritem Range) Lhs -> Rhs (Ritem range) [Num]\n");
+    for (i = 0; i < nrules + nuseless_productions; i++)
+      {
+       rule *rule_i = &rules[i];
+       item_number *r = NULL;
+       unsigned int rhs_itemno = rule_i->rhs - ritem;
+       unsigned int rhs_count = 0;
+       /* Find the last RHS index in ritems. */
+       for (r = rule_i->rhs; *r >= 0; ++r)
+         ++rhs_count;
+       fprintf (out, "%3d (%2d, %2d, %2d, %2u-%2u)   %2d ->",
+                i,
+                rule_i->prec ? rule_i->prec->prec : 0,
+                rule_i->prec ? rule_i->prec->assoc : 0,
+                rule_i->useful,
+                rhs_itemno,
+                rhs_itemno + rhs_count - 1,
+                rule_i->lhs->number);
+       /* Dumped the RHS. */
+       for (r = rule_i->rhs; *r >= 0; r++)
+         fprintf (out, " %3d", *r);
+       fprintf (out, "  [%d]\n", item_number_as_rule_number (*r));
+      }
+  }
+  fprintf (out, "\n\n");
+
+  fprintf (out, "Rules interpreted\n-----------------\n\n");
+  {
+    rule_number r;
+    for (r = 0; r < nrules + nuseless_productions; r++)
+      {
+       fprintf (out, "%-5d  ", r);
+       rule_print (&rules[r], out);
+      }
+  }
+  fprintf (out, "\n\n");
+}
+
+
+/*------------------------------------------------------------------.
+| Report on STDERR the rules that are not flagged USEFUL, using the |
+| MESSAGE (which can be `useless rule' when invoked after grammar   |
+| reduction, or `never reduced' after conflicts were taken into     |
+| account).                                                         |
+`------------------------------------------------------------------*/
+
+void
+grammar_rules_never_reduced_report (const char *message)
+{
+  rule_number r;
+  for (r = 0; r < nrules ; ++r)
+    if (!rules[r].useful)
+      {
+       location_print (stderr, rules[r].location);
+       fprintf (stderr, ": %s: %s: ",
+                _("warning"), message);
+       rule_print (&rules[r], stderr);
+      }
+}
+
+void
+grammar_free (void)
+{
+  XFREE (ritem);
+  free (rules);
+  XFREE (token_translations);
+  /* Free the symbol table data structure.  */
+  symbols_free ();
+  free_merger_functions ();
+}