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 a67bf2e246ad36d6650624b3aa9802bc3ba672d7..cf5a946db983e698269f6f2fa1aaa1800ecbc3ad 100644 (file)
--- a/src/gram.c
+++ b/src/gram.c
@@ -1,5 +1,6 @@
-/* Allocate input grammar variables for bison,
-   Copyright 1984, 1986, 1989, 2001 Free Software Foundation, Inc.
+/* 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.
 
 
    This file is part of Bison, the GNU Compiler Compiler.
 


@@ -20,35 +21,139 @@
 
 
 #include "system.h"
 
 
 #include "system.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.  */
+
+item_number *ritem = NULL;
+unsigned int nritems = 0;
+
+rule *rules = NULL;
+rule_number nrules = 0;
+
+symbol **symbols = NULL;
+int nsyms = 0;
+int ntokens = 1;
+int nvars = 0;
+
+symbol_number *token_translations = NULL;
+
+int max_user_token_number = 256;
+
+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;
+}

 
 

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

 
 

-int nitems;
-int nrules;
-int nsyms;
-int ntokens;
-int nvars;
+/*--------------------------------------------------------------------.
+| Return true IFF the rule is not flagged as useful *and* is useful.  |
+| In other words, it was discarded because of conflicts.              |
+`--------------------------------------------------------------------*/

 
 

-short *ritem = NULL;
-int nritems;
+bool
+rule_never_reduced_p (rule *r)
+{
+  return !r->useful && r->number < nrules;
+}

 
 

-rule_t *rule_table = NULL;

 
 

-struct bucket **symbols = NULL;
-short *token_translations = NULL;
+/*----------------------------------------------------------------.
+| 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 start_symbol;
+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);
+    }
+}

 
 

-int max_user_token_number;

 
 

-int semantic_parser;
+/*--------------------------------------.
+| Return the number of symbols in RHS.  |
+`--------------------------------------*/

 
 

-int pure_parser;
+int
+rule_rhs_length (rule *r)
+{
+  int res = 0;
+  item_number *rhsp;
+  for (rhsp = r->rhs; *rhsp >= 0; ++rhsp)
+    ++res;
+  return res;
+}

 
 

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

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


@@ -58,13 +163,13 @@ int error_token_number;
 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)
       fprintf (out, "  %s", symbols[ritem[i]]->tag);
     else
   fputs ("RITEM\n", out);
   for (i = 0; i < nritems; ++i)
     if (ritem[i] >= 0)
       fprintf (out, "  %s", symbols[ritem[i]]->tag);
     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);
 }
 


@@ -76,23 +181,158 @@ ritem_print (FILE *out)
 size_t
 ritem_longest_rhs (void)
 {
 size_t
 ritem_longest_rhs (void)
 {

-  int length;
-  int max;
-  int i;
+  int max = 0;
+  rule_number r;

 
 

-  length = 0;
-  max = 0;
-  for (i = 0; i < nritems; ++i)
-    if (ritem[i] >= 0)
+  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++)

       {
       {

-       length++;
+       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));

       }
       }

-    else
+  }
+  fprintf (out, "\n\n");
+
+  fprintf (out, "Rules interpreted\n-----------------\n\n");
+  {
+    rule_number r;
+    for (r = 0; r < nrules + nuseless_productions; r++)

       {
       {

-       if (length > max)
-         max = length;
-       length = 0;
+       fprintf (out, "%-5d  ", r);
+       rule_print (&rules[r], out);

       }
       }

+  }
+  fprintf (out, "\n\n");
+}

 
 

-  return max;
+
+/*------------------------------------------------------------------.
+| 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 ();

 }
 }