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 6d8fe0a74370ee8af51eef75c9d7ba61a9f6dfe2..cf5a946db983e698269f6f2fa1aaa1800ecbc3ad 100644 (file)
--- a/src/gram.c
+++ b/src/gram.c
@@ -1,4 +1,5 @@
-/* Allocate input grammar variables for bison,
+/* Allocate input grammar variables for Bison.
+

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


@@ -20,35 +21,91 @@
 
 
 #include "system.h"
 
 
 #include "system.h"

-#include "quotearg.h"
+
+#include <quotearg.h>
+

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

-#include "symtab.h"

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

+#include "reduce.h"
+#include "symtab.h"

 
 

-/* comments for these variables are in gram.h  */
+/* Comments for these variables are in gram.h.  */

 
 

-short *ritem = NULL;
-int nritems = 0;
+item_number *ritem = NULL;
+unsigned int nritems = 0;

 
 

-rule_t *rules = NULL;
-int nrules = 0;
+rule *rules = NULL;
+rule_number nrules = 0;

 
 

-symbol_t **symbols = NULL;
+symbol **symbols = NULL;

 int nsyms = 0;
 int ntokens = 1;
 int nvars = 0;
 
 int nsyms = 0;
 int ntokens = 1;
 int nvars = 0;
 

-short *token_translations = NULL;
-
-int start_symbol = 0;
+symbol_number *token_translations = NULL;

 
 int max_user_token_number = 256;
 
 
 int max_user_token_number = 256;
 

-int semantic_parser = 0;
-
+int glr_parser = 0;

 int pure_parser = 0;
 
 int pure_parser = 0;
 

-int error_token_number = 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;
+}
+
+
+/*----------------------------------------------------------------.
+| 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.                                            |
+`----------------------------------------------------------------*/
+
+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);
+    }
+}

 
 
 /*--------------------------------------.
 
 
 /*--------------------------------------.


@@ -56,16 +113,49 @@ int error_token_number = 0;
 `--------------------------------------*/
 
 int
 `--------------------------------------*/
 
 int

-rule_rhs_length (rule_t *rule)
+rule_rhs_length (rule *r)

 {
   int res = 0;
 {
   int res = 0;

-  short *rhsp;
-  for (rhsp = rule->rhs; *rhsp >= 0; ++rhsp)
+  item_number *rhsp;
+  for (rhsp = r->rhs; *rhsp >= 0; ++rhsp)

     ++res;
   return res;
 }
 
 
     ++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);
+}
+
+

 /*------------------------.
 | Dump RITEM for traces.  |
 `------------------------*/
 /*------------------------.
 | Dump RITEM for traces.  |
 `------------------------*/


@@ -73,14 +163,13 @@ rule_rhs_length (rule_t *rule)
 void
 ritem_print (FILE *out)
 {
 void
 ritem_print (FILE *out)
 {

-  int i;
+  unsigned int i;

   fputs ("RITEM\n", out);
   for (i = 0; i < nritems; ++i)
     if (ritem[i] >= 0)
   fputs ("RITEM\n", out);
   for (i = 0; i < nritems; ++i)
     if (ritem[i] >= 0)

-      fprintf (out, "  %s", quotearg_style (escape_quoting_style,
-                                           symbols[ritem[i]]->tag));
+      fprintf (out, "  %s", symbols[ritem[i]]->tag);

     else
     else

-      fprintf (out, "  (rule %d)\n", -ritem[i] - 1);
+      fprintf (out, "  (rule %d)\n", item_number_as_rule_number (ritem[i]));

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


@@ -93,14 +182,157 @@ size_t
 ritem_longest_rhs (void)
 {
   int max = 0;
 ritem_longest_rhs (void)
 {
   int max = 0;

-  int i;
+  rule_number r;

 
 

-  for (i = 1; i < nrules + 1; ++i)
+  for (r = 0; r < nrules; ++r)

     {
     {

-      int length = rule_rhs_length (&rules[i]);
+      int length = rule_rhs_length (&rules[r]);

       if (length > max)
        max = length;
     }
 
   return max;
 }
       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 ();
+}