Stop storing rules from 1 to nrules + 1.

[bison.git] / src / reduce.c

diff --git a/src/reduce.c b/src/reduce.c
index 4ac89197b77db3166cede68ff9ea20acb3bf3e48..154e63bf404af9d6279b2dde8044a3268fae58d8 100644 (file)
--- a/src/reduce.c
+++ b/src/reduce.c
@@ -50,10 +50,10 @@ static bitset V;
    `useless', but no warning should be issued).  */
 static bitset V1;
 
    `useless', but no warning should be issued).  */
 static bitset V1;
 

-static int nuseful_productions;
-int nuseless_productions;
+static rule_number_t nuseful_productions;
+rule_number_t nuseless_productions;

 static int nuseful_nonterminals;
 static int nuseful_nonterminals;

-int nuseless_nonterminals;
+symbol_number_t nuseless_nonterminals;

 \f
 /*-------------------------------------------------------------------.
 | Another way to do this would be with a set for each production and |
 \f
 /*-------------------------------------------------------------------.
 | Another way to do this would be with a set for each production and |


@@ -62,16 +62,15 @@ int nuseless_nonterminals;
 `-------------------------------------------------------------------*/
 
 static bool
 `-------------------------------------------------------------------*/
 
 static bool

-useful_production (int i, bitset N0)
+useful_production (rule_number_t r, bitset N0)

 {
 {

-  item_number_t *r;
-  short n;
+  item_number_t *rhsp;

 
   /* A production is useful if all of the nonterminals in its appear
      in the set of useful nonterminals.  */
 
 
   /* A production is useful if all of the nonterminals in its appear
      in the set of useful nonterminals.  */
 

-  for (r = rules[i].rhs; *r >= 0; r++)
-    if (ISVAR (n = *r) && !bitset_test (N0, n - ntokens))
+  for (rhsp = rules[r].rhs; *rhsp >= 0; ++rhsp)
+    if (ISVAR (*rhsp) && !bitset_test (N0, *rhsp - ntokens))

       return FALSE;
   return TRUE;
 }
       return FALSE;
   return TRUE;
 }


@@ -85,7 +84,7 @@ static void
 useless_nonterminals (void)
 {
   bitset Np, Ns;
 useless_nonterminals (void)
 {
   bitset Np, Ns;

-  int i;
+  rule_number_t r;

 
   /* N is set as built.  Np is set being built this iteration. P is
      set of all productions which have a RHS all in N.  */
 
   /* N is set as built.  Np is set being built this iteration. P is
      set of all productions which have a RHS all in N.  */


@@ -112,12 +111,12 @@ useless_nonterminals (void)
   while (1)
     {
       bitset_copy (Np, N);
   while (1)
     {
       bitset_copy (Np, N);

-      for (i = 1; i < nrules + 1; i++)
-       if (!bitset_test (P, i)
-           && useful_production (i, N))
+      for (r = 0; r < nrules; r++)
+       if (!bitset_test (P, r)
+           && useful_production (r, N))

          {
          {

-           bitset_set (Np, rules[i].lhs->number - ntokens);
-           bitset_set (P, i);
+           bitset_set (Np, rules[r].lhs->number - ntokens);
+           bitset_set (P, r);

          }
       if (bitset_equal_p (N, Np))
        break;
          }
       if (bitset_equal_p (N, Np))
        break;


@@ -134,9 +133,6 @@ static void
 inaccessable_symbols (void)
 {
   bitset Vp, Vs, Pp;
 inaccessable_symbols (void)
 {
   bitset Vp, Vs, Pp;

-  int i;
-  short t;
-  item_number_t *r;

 
   /* Find out which productions are reachable and which symbols are
      used.  Starting with an empty set of productions and a set of
 
   /* Find out which productions are reachable and which symbols are
      used.  Starting with an empty set of productions and a set of


@@ -162,26 +158,28 @@ inaccessable_symbols (void)
      user can know.  */
 
   Vp = bitset_create (nsyms, BITSET_FIXED);
      user can know.  */
 
   Vp = bitset_create (nsyms, BITSET_FIXED);

-  Pp = bitset_create (nrules + 1, BITSET_FIXED);
+  Pp = bitset_create (nrules, BITSET_FIXED);

 
   /* If the start symbol isn't useful, then nothing will be useful. */
 
   /* If the start symbol isn't useful, then nothing will be useful. */

-  if (bitset_test (N, start_symbol - ntokens))
+  if (bitset_test (N, axiom->number - ntokens))

     {
     {

-      bitset_set (V, start_symbol);
+      bitset_set (V, axiom->number);

 
       while (1)
        {
 
       while (1)
        {

+         rule_number_t r;

          bitset_copy (Vp, V);
          bitset_copy (Vp, V);

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

            {
            {

-             if (!bitset_test (Pp, i)
-                 && bitset_test (P, i)
-                 && bitset_test (V, rules[i].lhs->number))
+             if (!bitset_test (Pp, r)
+                 && bitset_test (P, r)
+                 && bitset_test (V, rules[r].lhs->number))

                {
                {

-                 for (r = rules[i].rhs; *r >= 0; r++)
-                   if (ISTOKEN (t = *r) || bitset_test (N, t - ntokens))
-                     bitset_set (Vp, t);
-                 bitset_set (Pp, i);
+                 item_number_t *rhsp;
+                 for (rhsp = rules[r].rhs; *rhsp >= 0; rhsp++)
+                   if (ISTOKEN (*rhsp) || bitset_test (N, *rhsp - ntokens))
+                     bitset_set (Vp, *rhsp);
+                 bitset_set (Pp, r);

                }
            }
          if (bitset_equal_p (V, Vp))
                }
            }
          if (bitset_equal_p (V, Vp))


@@ -207,15 +205,21 @@ inaccessable_symbols (void)
   nuseless_productions = nrules - nuseful_productions;
 
   nuseful_nonterminals = 0;
   nuseless_productions = nrules - nuseful_productions;
 
   nuseful_nonterminals = 0;

-  for (i = ntokens; i < nsyms; i++)
-    if (bitset_test (V, i))
-      nuseful_nonterminals++;
+  {
+    symbol_number_t i;
+    for (i = ntokens; i < nsyms; i++)
+      if (bitset_test (V, i))
+       nuseful_nonterminals++;
+  }

   nuseless_nonterminals = nvars - nuseful_nonterminals;
 
   /* A token that was used in %prec should not be warned about.  */
   nuseless_nonterminals = nvars - nuseful_nonterminals;
 
   /* A token that was used in %prec should not be warned about.  */

-  for (i = 1; i < nrules + 1; i++)
-    if (rules[i].precsym != 0)
-      bitset_set (V1, rules[i].precsym->number);
+  {
+    rule_number_t r;
+    for (r = 0; r < nrules; ++r)
+      if (rules[r].precsym != 0)
+       bitset_set (V1, rules[r].precsym->number);
+  }

 }
 
 
 }
 
 


@@ -227,33 +231,41 @@ inaccessable_symbols (void)
 static void
 reduce_grammar_tables (void)
 {
 static void
 reduce_grammar_tables (void)
 {

-  /* Flag useless productions.  */
+  /* Report and flag useless productions.  */

   {
   {

-    int pn;
-    for (pn = 1; pn < nrules + 1; pn++)
-      rules[pn].useful = bitset_test (P, pn);
+    rule_number_t r;
+    for (r = 0; r < nrules; r++)
+      {
+       rules[r].useful = bitset_test (P, r);
+       if (!rules[r].useful)
+         {
+           LOCATION_PRINT (stderr, rules[r].location);
+           fprintf (stderr, ": %s: %s: ", _("warning"), _("useless rule"));
+           rule_print (&rules[r], stderr);
+         }
+      }

   }
 
   /* Map the nonterminals to their new index: useful first, useless
      afterwards.  Kept for later report.  */
   {
   }
 
   /* Map the nonterminals to their new index: useful first, useless
      afterwards.  Kept for later report.  */
   {

-    int useful = 1;
-    int useless = nrules + 1 - nuseless_productions;
-    rule_t *rules_sorted = XMALLOC (rule_t, nrules + 1) - 1;
-    int i;
-    for (i = 1; i < nrules + 1; ++i)
-      rules_sorted[rules[i].useful ? useful++ : useless++] = rules[i];
-    free (rules + 1);
+    int useful = 0;
+    int useless = nrules - nuseless_productions;
+    rule_t *rules_sorted = XMALLOC (rule_t, nrules);
+    rule_number_t r;
+    for (r = 0; r < nrules; ++r)
+      rules_sorted[rules[r].useful ? useful++ : useless++] = rules[r];
+    free (rules);

     rules = rules_sorted;
 
     /* Renumber the rules markers in RITEMS.  */
     rules = rules_sorted;
 
     /* Renumber the rules markers in RITEMS.  */

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

       {
       {

-       item_number_t *rhsp = rules[i].rhs;
+       item_number_t *rhsp = rules[r].rhs;

        for (/* Nothing. */; *rhsp >= 0; ++rhsp)
          /* Nothing. */;
        for (/* Nothing. */; *rhsp >= 0; ++rhsp)
          /* Nothing. */;

-       *rhsp = -i;
-       rules[i].number = i;
+       *rhsp = rule_number_as_item_number (r);
+       rules[r].number = r;

       }
     nrules -= nuseless_productions;
   }
       }
     nrules -= nuseless_productions;
   }


@@ -262,7 +274,7 @@ reduce_grammar_tables (void)
   {
     int r;
     int length;
   {
     int r;
     int length;

-    for (r = nrules + 1; r < nrules + 1 + nuseless_productions; ++r)
+    for (r = nrules; r < nrules + nuseless_productions; ++r)

       {
        length = rule_rhs_length (&rules[r]);
        nritems -= length + 1;
       {
        length = rule_rhs_length (&rules[r]);
        nritems -= length + 1;


@@ -290,7 +302,13 @@ nonterminals_reduce (void)
       nontermmap[i] = n++;
   for (i = ntokens; i < nsyms; i++)
     if (!bitset_test (V, i))
       nontermmap[i] = n++;
   for (i = ntokens; i < nsyms; i++)
     if (!bitset_test (V, i))

-      nontermmap[i] = n++;
+      {
+       nontermmap[i] = n++;
+       LOCATION_PRINT (stderr, symbols[i]->location);
+       fprintf (stderr, ": %s: %s: %s\n",
+                _("warning"), _("useless nonterminal"),
+                symbols[i]->tag);
+      }

 
 
   /* Shuffle elements of tables indexed by symbol number.  */
 
 
   /* Shuffle elements of tables indexed by symbol number.  */


@@ -307,15 +325,15 @@ nonterminals_reduce (void)
   }
 
   {
   }
 
   {

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

       {
        item_number_t *rhsp;
        for (rhsp = rules[r].rhs; *rhsp >= 0; ++rhsp)
          if (ISVAR (*rhsp))
            *rhsp =  symbol_number_as_item_number (nontermmap[*rhsp]);
       }
       {
        item_number_t *rhsp;
        for (rhsp = rules[r].rhs; *rhsp >= 0; ++rhsp)
          if (ISVAR (*rhsp))
            *rhsp =  symbol_number_as_item_number (nontermmap[*rhsp]);
       }

-    start_symbol = nontermmap[start_symbol];
+    axiom->number = nontermmap[axiom->number];

   }
 
   nsyms -= nuseless_nonterminals;
   }
 
   nsyms -= nuseless_nonterminals;


@@ -337,8 +355,7 @@ reduce_output (FILE *out)
       int i;
       fprintf (out, "%s\n\n", _("Useless nonterminals:"));
       for (i = 0; i < nuseless_nonterminals; ++i)
       int i;
       fprintf (out, "%s\n\n", _("Useless nonterminals:"));
       for (i = 0; i < nuseless_nonterminals; ++i)

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

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


@@ -351,30 +368,16 @@ reduce_output (FILE *out)
          if (!b)
            fprintf (out, "%s\n\n", _("Terminals which are not used:"));
          b = TRUE;
          if (!b)
            fprintf (out, "%s\n\n", _("Terminals which are not used:"));
          b = TRUE;

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

        }
     if (b)
       fputs ("\n\n", out);
   }
 
   if (nuseless_productions > 0)
        }
     if (b)
       fputs ("\n\n", out);
   }
 
   if (nuseless_productions > 0)

-    {
-      int i;
-      fprintf (out, "%s\n\n", _("Useless rules:"));
-      for (i = nrules + 1; i < nuseless_productions + nrules + 1; i++)
-       {
-         item_number_t *r;
-         fprintf (out, "#%-4d  ", rules[i].user_number - 1);
-         fprintf (out, "%s:", quotearg_style (escape_quoting_style,
-                                              rules[i].lhs->tag));
-         for (r = rules[i].rhs; *r >= 0; r++)
-           fprintf (out, " %s", quotearg_style (escape_quoting_style,
-                                                symbols[*r]->tag));
-         fputs (";\n", out);
-       }
-      fputs ("\n\n", out);
-    }
+    grammar_rules_partial_print (out, _("Useless rules"),
+                                nrules,
+                                nrules + nuseless_productions);

 }
 \f
 
 }
 \f
 


@@ -394,7 +397,7 @@ reduce_print (void)
                               nuseless_productions),
             nuseless_productions);
 
                               nuseless_productions),
             nuseless_productions);
 

-  fprintf (stderr, _("%s contains "), infile);
+  fprintf (stderr, "%s: %s: ", infile, _("warning"));

 
   if (nuseless_nonterminals > 0)
     fprintf (stderr, ngettext ("%d useless nonterminal",
 
   if (nuseless_nonterminals > 0)
     fprintf (stderr, ngettext ("%d useless nonterminal",


@@ -422,7 +425,7 @@ reduce_grammar (void)
   /* Allocate the global sets used to compute the reduced grammar */
 
   N = bitset_create (nvars, BITSET_FIXED);
   /* Allocate the global sets used to compute the reduced grammar */
 
   N = bitset_create (nvars, BITSET_FIXED);

-  P =  bitset_create (nrules + 1, BITSET_FIXED);
+  P =  bitset_create (nrules, BITSET_FIXED);

   V = bitset_create (nsyms, BITSET_FIXED);
   V1 = bitset_create (nsyms, BITSET_FIXED);
 
   V = bitset_create (nsyms, BITSET_FIXED);
   V1 = bitset_create (nsyms, BITSET_FIXED);
 


@@ -435,9 +438,9 @@ reduce_grammar (void)
 
   reduce_print ();
 
 
   reduce_print ();
 

-  if (!bitset_test (N, start_symbol - ntokens))
+  if (!bitset_test (N, axiom->number - ntokens))

     fatal (_("Start symbol %s does not derive any sentence"),
     fatal (_("Start symbol %s does not derive any sentence"),

-          quotearg_style (escape_quoting_style, symbols[start_symbol]->tag));
+          symbols[axiom->number]->tag);

 
   /* First reduce the nonterminals, as they renumber themselves in the
      whole grammar.  If you change the order, nonterms would be
 
   /* First reduce the nonterminals, as they renumber themselves in the
      whole grammar.  If you change the order, nonterms would be