doc: create a new Tuning LR section in the manual.

[bison.git] / src / reduce.c

diff --git a/src/reduce.c b/src/reduce.c
index 2e309a44bd77081c43d1a9f4e749693603cac1bc..7a30e55532b2f197da93c46f36947f3ead6e75da 100644 (file)
--- a/src/reduce.c
+++ b/src/reduce.c
@@ -1,7 +1,7 @@
 /* Grammar reduction for Bison.
 
-   Copyright (C) 1988, 1989, 2000, 2001, 2002, 2003, 2005, 2006,
-   2007 Free Software Foundation, Inc.
+   Copyright (C) 1988-1989, 2000-2003, 2005-2011 Free Software
+   Foundation, Inc.
 
    This file is part of Bison, the GNU Compiler Compiler.
 
@@ -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);
        }
@@ -370,65 +370,8 @@ reduce_output (FILE *out)
   }
 
   if (nuseless_productions > 0)
-    grammar_rules_partial_print (out, _("Useless rules"),
-                                rule_useless_p);
-}
-\f
-
-/*--------------------------------------------------------------.
-| Output the detailed results of the reductions.  For FILE.xml. |
-`---------------------------------------------------------------*/
-
-void
-reduce_xml (FILE *out, int level)
-{
-  fputc ('\n', out);
-  xml_puts (out, level, "<reductions>");
-  xml_puts (out, level + 1, "<useless>");
-
-  if (nuseless_nonterminals > 0)
-    {
-      int i;
-      xml_puts (out, level + 2, "<nonterminals>");
-      for (i = 0; i < nuseless_nonterminals; ++i)
-       xml_printf (out, level + 3,
-                   "<nonterminal>%s</nonterminal>",
-                   symbols[nsyms + i]->tag);
-      xml_puts (out, level + 2, "</nonterminals>");
-    }
-  else
-    xml_puts (out, level + 2, "<nonterminals/>");
-
-  if (nuseless_productions > 0)
-    grammar_rules_partial_print_xml (out, level + 1, true, rule_useless_p);
-  else
-    xml_puts (out, level + 2, "<rules/>");
-
-  xml_puts (out, level + 1, "</useless>");
-  xml_puts (out, level + 1, "<unused>");
-
-  {
-    bool b = false;
-    int i;
-    for (i = 0; i < ntokens; i++)
-      if (!bitset_test (V, i) && !bitset_test (V1, i))
-       {
-         if (!b)
-           xml_puts (out, level + 2, "<terminals>");
-         b = true;
-         xml_printf (out, level + 3,
-                     "<terminal>%s</terminal>",
-                     xml_escape (symbols[i]->tag));
-       }
-    if (b)
-      xml_puts (out, level + 2, "</terminals>");
-    else
-      xml_puts (out, level + 2, "<terminals/>");
-  }
-
-  xml_puts (out, level + 1, "</unused>");
-  xml_puts (out, level, "</reductions>");
-  fputc ('\n', out);
+    grammar_rules_partial_print (out, _("Rules useless in grammar"),
+                                rule_useless_in_grammar_p);
 }
 \f
 
@@ -439,29 +382,16 @@ reduce_xml (FILE *out, int level)
 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 "));
-
+    warn (ngettext ("%d nonterminal useless in grammar",
+                    "%d nonterminals useless in grammar",
+                    nuseless_nonterminals),
+          nuseless_nonterminals);
   if (nuseless_productions > 0)
-    fprintf (stderr, ngettext ("%d useless rule",
-                              "%d useless rules",
-                              nuseless_productions),
-            nuseless_productions);
-  fprintf (stderr, "\n");
+    warn (ngettext ("%d rule useless in grammar",
+                    "%d rules useless in grammar",
+                    nuseless_productions),
+          nuseless_productions);
 }
 \f
 void
@@ -508,6 +438,19 @@ 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.  |