X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/12b0043a6d9648eedaa64a4c8445fd9e9a9f781c..f377f69fec28013c79db4efe12bbb9d48987fb2c:/src/reduce.c

diff --git a/src/reduce.c b/src/reduce.c
index fb975972..7bbd8954 100644
--- a/src/reduce.c
+++ b/src/reduce.c
@@ -111,7 +111,7 @@ useless_nonterminals (void)
   while (1)
     {
       bitset_copy (Np, N);
-      for (r = 1; r < nrules + 1; r++)
+      for (r = 0; r < nrules; r++)
 	if (!bitset_test (P, r)
 	    && useful_production (r, N))
 	  {
@@ -158,18 +158,18 @@ inaccessable_symbols (void)
      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 (bitset_test (N, axiom->number - ntokens))
+  if (bitset_test (N, accept->number - ntokens))
     {
-      bitset_set (V, axiom->number);
+      bitset_set (V, accept->number);
 
       while (1)
 	{
 	  rule_number_t r;
 	  bitset_copy (Vp, V);
-	  for (r = 1; r < nrules + 1; r++)
+	  for (r = 0; r < nrules; r++)
 	    {
 	      if (!bitset_test (Pp, r)
 		  && bitset_test (P, r)
@@ -194,7 +194,7 @@ inaccessable_symbols (void)
   V = Vp;
 
   /* Tokens 0, 1, and 2 are internal to Bison.  Consider them useful. */
-  bitset_set (V, eoftoken->number);		/* end-of-input token */
+  bitset_set (V, endtoken->number);		/* end-of-input token */
   bitset_set (V, errtoken->number);		/* error token */
   bitset_set (V, undeftoken->number);		/* some undefined token */
 
@@ -215,10 +215,10 @@ inaccessable_symbols (void)
 
   /* A token that was used in %prec should not be warned about.  */
   {
-    rule_number_t i;
-    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);
   }
 }
 
@@ -234,32 +234,25 @@ reduce_grammar_tables (void)
   /* Report and flag useless productions.  */
   {
     rule_number_t r;
-    for (r = 1; r < nrules + 1; 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);
-	  }
-      }
+    for (r = 0; r < nrules; r++)
+      rules[r].useful = bitset_test (P, r);
+    grammar_rules_never_reduced_report (_("useless rule"));
   }
 
   /* 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 useful = 0;
+    int useless = nrules - nuseless_productions;
+    rule_t *rules_sorted = XMALLOC (rule_t, nrules);
     rule_number_t r;
-    for (r = 1; r < nrules + 1; ++r)
+    for (r = 0; r < nrules; ++r)
       rules_sorted[rules[r].useful ? useful++ : useless++] = rules[r];
-    free (rules + 1);
+    free (rules);
     rules = rules_sorted;
 
     /* Renumber the rules markers in RITEMS.  */
-    for (r = 1; r < nrules + 1; ++r)
+    for (r = 0; r < nrules; ++r)
       {
 	item_number_t *rhsp = rules[r].rhs;
 	for (/* Nothing. */; *rhsp >= 0; ++rhsp)
@@ -274,7 +267,7 @@ reduce_grammar_tables (void)
   {
     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;
@@ -326,14 +319,14 @@ nonterminals_reduce (void)
 
   {
     rule_number_t r;
-    for (r = 1; r < nrules + 1; ++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]);
       }
-    axiom->number = nontermmap[axiom->number];
+    accept->number = nontermmap[accept->number];
   }
 
   nsyms -= nuseless_nonterminals;
@@ -353,7 +346,7 @@ reduce_output (FILE *out)
   if (nuseless_nonterminals > 0)
     {
       int i;
-      fprintf (out, "%s\n\n", _("Useless nonterminals:"));
+      fprintf (out, "%s\n\n", _("Useless nonterminals"));
       for (i = 0; i < nuseless_nonterminals; ++i)
 	fprintf (out, "   %s\n", symbols[nsyms + i]->tag);
       fputs ("\n\n", out);
@@ -366,7 +359,7 @@ reduce_output (FILE *out)
       if (!bitset_test (V, i) && !bitset_test (V1, i))
 	{
 	  if (!b)
-	    fprintf (out, "%s\n\n", _("Terminals which are not used:"));
+	    fprintf (out, "%s\n\n", _("Terminals which are not used"));
 	  b = TRUE;
 	  fprintf (out, "   %s\n", symbols[i]->tag);
 	}
@@ -376,8 +369,7 @@ reduce_output (FILE *out)
 
   if (nuseless_productions > 0)
     grammar_rules_partial_print (out, _("Useless rules"),
-				 nrules + 1,
-				 nuseless_productions + nrules + 1);
+				 rule_useless_p);
 }
 
 
@@ -425,7 +417,7 @@ reduce_grammar (void)
   /* 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);
 
@@ -438,9 +430,10 @@ reduce_grammar (void)
 
   reduce_print ();
 
-  if (!bitset_test (N, axiom->number - ntokens))
-    fatal (_("Start symbol %s does not derive any sentence"),
-	   symbols[axiom->number]->tag);
+  if (!bitset_test (N, accept->number - ntokens))
+    fatal_at (startsymbol_location,
+	      _("start symbol %s does not derive any sentence"),
+	      startsymbol->tag);
 
   /* First reduce the nonterminals, as they renumber themselves in the
      whole grammar.  If you change the order, nonterms would be
@@ -450,7 +443,7 @@ reduce_grammar (void)
   if (nuseless_productions > 0)
     reduce_grammar_tables ();
 
-  if (trace_flag)
+  if (trace_flag & trace_grammar)
     {
       grammar_dump (stderr, "Reduced Grammar");