* src/gram.c, src/gram.h (ritem_print): New.

[bison.git] / src / reduce.c

diff --git a/src/reduce.c b/src/reduce.c
index 7e164c50633e0eef306fa7472db69b83248434a7..048f5a632236524fd78fd15f95c6b2b84bb77f04 100644 (file)
--- a/src/reduce.c
+++ b/src/reduce.c
@@ -310,20 +310,12 @@ reduce_grammar_tables (void)
 
     }
 #endif /* 0 */
-  /* Disable useless productions,
-     since they may contain useless nonterms
-     that would get mapped below to -1 and confuse everyone.  */
+  /* Disable useless productions. */
   if (nuseless_productions > 0)
     {
       int pn;
-
       for (pn = 1; pn <= nrules; pn++)
-       {
-         if (!BITISSET (P, pn))
-           {
-             rule_table[pn].lhs = -1;
-           }
-       }
+       rule_table[pn].useful = BITISSET (P, pn);
     }
 }
 
@@ -338,8 +330,8 @@ nonterminals_reduce (void)
   int i, n;
   rule r;
 
-  /* Create a map of nonterminal number to new nonterminal number. -1
-     in the map means it was useless and is being eliminated.  */
+  /* Map the nonterminals to their new index: useful first, useless
+     afterwards.  Kept for later report.  */
 
   short *nontermmap = XCALLOC (short, nvars) - ntokens;
   n = ntokens;
@@ -379,9 +371,7 @@ nonterminals_reduce (void)
 
   for (i = 1; i <= nrules; i++)
     {
-      /* Ignore the rules disabled above.  */
-      if (rule_table[i].lhs >= 0)
-       rule_table[i].lhs = nontermmap[rule_table[i].lhs];
+      rule_table[i].lhs = nontermmap[rule_table[i].lhs];
       if (ISVAR (rule_table[i].precsym))
        /* Can this happen?  */
        rule_table[i].precsym = nontermmap[rule_table[i].precsym];
@@ -396,7 +386,7 @@ nonterminals_reduce (void)
   nsyms -= nuseless_nonterminals;
   nvars -= nuseless_nonterminals;
 
-  free (&nontermmap[ntokens]);
+  free (nontermmap + ntokens);
 }
 
 
@@ -407,50 +397,46 @@ nonterminals_reduce (void)
 void
 reduce_output (FILE *out)
 {
-  int i;
-  rule r;
-  bool b;
-
   if (nuseless_nonterminals > 0)
     {
-      fprintf (out, _("Useless nonterminals:"));
-      fprintf (out, "\n\n");
+      int i;
+      fprintf (out, "%s\n\n", _("Useless nonterminals:"));
       for (i = 0; i < nuseless_nonterminals; ++i)
        fprintf (out, "   %s\n", tags[nsyms + i]);
+      fputs ("\n\n", out);
     }
-  b = FALSE;
-  for (i = 0; i < ntokens; i++)
-    {
+
+  {
+    bool b = FALSE;
+    int i;
+    for (i = 0; i < ntokens; i++)
       if (!BITISSET (V, i) && !BITISSET (V1, i))
        {
          if (!b)
-           {
-             fprintf (out, "\n\n");
-             fprintf (out, _("Terminals which are not used:"));
-             fprintf (out, "\n\n");
-             b = TRUE;
-           }
+           fprintf (out, "%s\n\n", _("Terminals which are not used:"));
+         b = TRUE;
          fprintf (out, "   %s\n", tags[i]);
        }
-    }
+    if (b)
+      fputs ("\n\n", out);
+  }
 
   if (nuseless_productions > 0)
     {
-      fprintf (out, "\n\n");
-      fprintf (out, _("Useless rules:"));
-      fprintf (out, "\n\n");
+      int i;
+      fprintf (out, "%s\n\n", _("Useless rules:"));
       for (i = 1; i <= nrules; i++)
-       if (!BITISSET (P, i))
+       if (!rule_table[i].useful)
          {
+           rule r;
            fprintf (out, "#%-4d  ", i);
-           fprintf (out, "%s :\t", tags[rule_table[i].lhs]);
+           fprintf (out, "%s:", tags[rule_table[i].lhs]);
            for (r = &ritem[rule_table[i].rhs]; *r >= 0; r++)
              fprintf (out, " %s", tags[*r]);
-           fprintf (out, ";\n");
+           fputs (";\n", out);
          }
+      fputs ("\n\n", out);
     }
-  if (nuseless_nonterminals > 0 || nuseless_productions > 0 || b)
-    fprintf (out, "\n\n");
 }
 \f
 static void
@@ -469,18 +455,22 @@ dump_grammar (FILE *out)
     fprintf (out, "%5d  %5d   %5d  %s\n", i, sprec[i], sassoc[i], tags[i]);
   fprintf (out, "\n\n");
   fprintf (out, "Rules\n-----\n\n");
-  fprintf (out, "Num (Prec, Assoc) Lhs : (@Rhs) Ritems [Num?]\n");
+  fprintf (out, "Num (Prec, Assoc, Useful, Ritem Range) Lhs -> Rhs (Ritem range) [Num]\n");
   for (i = 1; i <= nrules; i++)
     {
-      fprintf (out, "%-5d(%5d%5d)%5d : (@%-5d)",
+      int rhs_count = 0;
+      /* Find the last RHS index in ritems. */
+      for (r = &ritem[rule_table[i].rhs]; *r > 0; ++r)
+       ++rhs_count;
+      fprintf (out, "%3d (%2d, %2d, %2d, %2d-%2d)   %2d ->",
               i,
-              rule_table[i].prec,
-              rule_table[i].assoc,
-              rule_table[i].lhs,
-              rule_table[i].rhs);
+              rule_table[i].prec, rule_table[i].assoc, rule_table[i].useful,
+              rule_table[i].rhs, rule_table[i].rhs + rhs_count - 1,
+              rule_table[i].lhs);
+      /* Dumped the RHS. */
       for (r = &ritem[rule_table[i].rhs]; *r > 0; r++)
-       fprintf (out, "%5d", *r);
-      fprintf (out, " [%d]\n", -(*r));
+       fprintf (out, "%3d", *r);
+      fprintf (out, "  [%d]\n", -(*r));
     }
   fprintf (out, "\n\n");
   fprintf (out, "Rules interpreted\n-----------------\n\n");