Add new files for IELR and canonical LR implementation.

[bison.git] / src / reduce.c

diff --git a/src/reduce.c b/src/reduce.c
index a6b9e629089ed7ea4fd9d7cd2f557130d2ee7d5f..596a26bc8204d451e3f635a141377cac78cdfed5 100644 (file)
--- a/src/reduce.c
+++ b/src/reduce.c
@@ -1,24 +1,22 @@
 /* Grammar reduction for Bison.
 
-   Copyright (C) 1988, 1989, 2000, 2001, 2002, 2003 Free Software
-   Foundation, Inc.
+   Copyright (C) 1988, 1989, 2000, 2001, 2002, 2003, 2005, 2006,
+   2007, 2008 Free Software Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
-   Bison is free software; you can redistribute it and/or modify
+   This program 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.
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
 
-   Bison is distributed in the hope that it will be useful,
+   This program 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., 51 Franklin Street, Fifth Floor,
-   Boston, MA 02110-1301, USA.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
 
 /* Reduce the grammar: Find and eliminate unreachable terminals,
@@ -27,6 +25,7 @@
 /* Don't eliminate unreachable terminals: They may be used by the
    user's parser.  */
 
+#include <config.h>
 #include "system.h"
 
 #include <bitset.h>
@@ -36,6 +35,7 @@
 #include "files.h"
 #include "getargs.h"
 #include "gram.h"
+#include "print-xml.h"
 #include "reader.h"
 #include "reduce.h"
 #include "symtab.h"
@@ -239,7 +239,7 @@ reduce_grammar_tables (void)
     rule_number r;
     for (r = 0; r < nrules; r++)
       rules[r].useful = bitset_test (P, r);
-    grammar_rules_never_reduced_report (_("useless rule"));
+    grammar_rules_useless_report (_("rule useless in grammar"));
   }
 
   /* Map the nonterminals to their new index: useful first, useless
@@ -300,7 +300,7 @@ nonterminals_reduce (void)
     if (!bitset_test (V, i))
       {
        nontermmap[i - ntokens] = n++;
-       warn_at (symbols[i]->location, _("useless nonterminal: %s"),
+       warn_at (symbols[i]->location, _("nonterminal useless in grammar: %s"),
                 symbols[i]->tag);
       }
 
@@ -348,7 +348,7 @@ reduce_output (FILE *out)
   if (nuseless_nonterminals > 0)
     {
       int i;
-      fprintf (out, "%s\n\n", _("Useless nonterminals"));
+      fprintf (out, "%s\n\n", _("Nonterminals useless in grammar"));
       for (i = 0; i < nuseless_nonterminals; ++i)
        fprintf (out, "   %s\n", symbols[nsyms + i]->tag);
       fputs ("\n\n", out);
@@ -358,10 +358,10 @@ reduce_output (FILE *out)
     bool b = false;
     int i;
     for (i = 0; i < ntokens; i++)
-      if (!bitset_test (V, i) && !bitset_test (V1, i))
+      if (reduce_token_unused_in_grammar (i))
        {
          if (!b)
-           fprintf (out, "%s\n\n", _("Terminals which are not used"));
+           fprintf (out, "%s\n\n", _("Terminals unused in grammar"));
          b = true;
          fprintf (out, "   %s\n", symbols[i]->tag);
        }
@@ -370,14 +370,11 @@ reduce_output (FILE *out)
   }
 
   if (nuseless_productions > 0)
-    grammar_rules_partial_print (out, _("Useless rules"),
-                                rule_useless_p);
+    grammar_rules_partial_print (out, _("Rules useless in grammar"),
+                                rule_useless_in_grammar_p);
 }
 \f
 
-
-
-
 /*-------------------------------.
 | Report the results to STDERR.  |
 `-------------------------------*/
@@ -385,29 +382,24 @@ reduce_output (FILE *out)
 static void
 reduce_print (void)
 {
-  if (yacc_flag && nuseless_productions)
-    fprintf (stderr, ngettext ("%d rule never reduced\n",
-                              "%d rules never reduced\n",
-                              nuseless_productions),
-            nuseless_productions);
-
-  fprintf (stderr, "%s: %s: ", grammar_file, _("warning"));
-
   if (nuseless_nonterminals > 0)
-    fprintf (stderr, ngettext ("%d useless nonterminal",
-                              "%d useless nonterminals",
-                              nuseless_nonterminals),
-            nuseless_nonterminals);
-
-  if (nuseless_nonterminals > 0 && nuseless_productions > 0)
-    fprintf (stderr, _(" and "));
-
+    {
+      fprintf (stderr, "%s: %s: ", grammar_file, _("warning"));
+      fprintf (stderr, ngettext ("%d nonterminal useless in grammar",
+                                 "%d nonterminals useless in grammar",
+                                 nuseless_nonterminals),
+               nuseless_nonterminals);
+      fprintf (stderr, "\n");
+    }
   if (nuseless_productions > 0)
-    fprintf (stderr, ngettext ("%d useless rule",
-                              "%d useless rules",
-                              nuseless_productions),
-            nuseless_productions);
-  fprintf (stderr, "\n");
+    {
+      fprintf (stderr, "%s: %s: ", grammar_file, _("warning"));
+      fprintf (stderr, ngettext ("%d rule useless in grammar",
+                                 "%d rules useless in grammar",
+                                 nuseless_productions),
+               nuseless_productions);
+      fprintf (stderr, "\n");
+    }
 }
 \f
 void
@@ -425,7 +417,7 @@ reduce_grammar (void)
   useless_nonterminals ();
   inaccessable_symbols ();
 
-  reduced = (bool) (nuseless_nonterminals + nuseless_productions > 0);
+  reduced = (nuseless_nonterminals + nuseless_productions > 0);
   if (!reduced)
     return;
 
@@ -454,6 +446,19 @@ reduce_grammar (void)
     }
 }
 
+bool
+reduce_token_unused_in_grammar (symbol_number i)
+{
+  aver (i < ntokens);
+  return !bitset_test (V, i) && !bitset_test (V1, i);
+}
+
+bool
+reduce_nonterminal_useless_in_grammar (symbol_number i)
+{
+  aver (ntokens <= i && i < nsyms + nuseless_nonterminals);
+  return nsyms <= i;
+}
 
 /*-----------------------------------------------------------.
 | Free the global sets used to compute the reduced grammar.  |