X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/9222837b2743308e4971fc0ad299ca2f73fb20ae..c97011bfc1cabd3f7aa8e263f83d9e8a18a262bf:/src/gram.c

diff --git a/src/gram.c b/src/gram.c
index 708922d5..ebb7e739 100644
--- a/src/gram.c
+++ b/src/gram.c
@@ -47,6 +47,64 @@ int glr_parser = 0;
 int pure_parser = 0;
 
 
+/*--------------------------------------------------------------.
+| Return true IFF the rule has a `number' smaller than NRULES.  |
+`--------------------------------------------------------------*/
+
+bool
+rule_useful_p (rule_t *r)
+{
+  return r->number < nrules;
+}
+
+
+/*-------------------------------------------------------------.
+| Return true IFF the rule has a `number' higher than NRULES.  |
+`-------------------------------------------------------------*/
+
+bool
+rule_useless_p (rule_t *r)
+{
+  return r->number >= nrules;
+}
+
+
+/*--------------------------------------------------------------------.
+| Return true IFF the rule is not flagged as useful *and* is useful.  |
+| In other words, it was discarded because of conflicts.              |
+`--------------------------------------------------------------------*/
+
+bool
+rule_never_reduced_p (rule_t *r)
+{
+  return !r->useful && r->number < nrules;
+}
+
+
+/*----------------------------------------------------------------.
+| Print this RULE's number and lhs on OUT.  If a PREVIOUS_LHS was |
+| already displayed (by a previous call for another rule), avoid  |
+| useless repetitions.                                            |
+`----------------------------------------------------------------*/
+
+void
+rule_lhs_print (rule_t *rule, symbol_t *previous_lhs, FILE *out)
+{
+  fprintf (out, "  %3d ", rule->number);
+  if (previous_lhs != rule->lhs)
+    {
+      fprintf (out, "%s:", rule->lhs->tag);
+    }
+  else
+    {
+      int n;
+      for (n = strlen (previous_lhs->tag); n > 0; --n)
+	fputc (' ', out);
+      fputc ('|', out);
+    }
+}
+
+
 /*--------------------------------------.
 | Return the number of symbols in RHS.  |
 `--------------------------------------*/
@@ -73,7 +131,7 @@ rule_rhs_print (rule_t *rule, FILE *out)
     {
       item_number_t *r;
       for (r = rule->rhs; *r >= 0; r++)
-	fprintf (out, " %s", symbol_tag_get (symbols[*r]));
+	fprintf (out, " %s", symbols[*r]->tag);
       fputc ('\n', out);
     }
   else
@@ -90,7 +148,7 @@ rule_rhs_print (rule_t *rule, FILE *out)
 void
 rule_print (rule_t *rule, FILE *out)
 {
-  fprintf (out, "%s:", symbol_tag_get (rule->lhs));
+  fprintf (out, "%s:", rule->lhs->tag);
   rule_rhs_print (rule, out);
 }
 
@@ -106,9 +164,9 @@ ritem_print (FILE *out)
   fputs ("RITEM\n", out);
   for (i = 0; i < nritems; ++i)
     if (ritem[i] >= 0)
-      fprintf (out, "  %s", symbol_tag_get (symbols[ritem[i]]));
+      fprintf (out, "  %s", symbols[ritem[i]]->tag);
     else
-      fprintf (out, "  (rule %d)\n", -ritem[i] - 1);
+      fprintf (out, "  (rule %d)\n", item_number_as_rule_number (ritem[i]));
   fputs ("\n\n", out);
 }
 
@@ -123,7 +181,7 @@ ritem_longest_rhs (void)
   int max = 0;
   rule_number_t r;
 
-  for (r = 1; r < nrules + 1; ++r)
+  for (r = 0; r < nrules; ++r)
     {
       int length = rule_rhs_length (&rules[r]);
       if (length > max)
@@ -134,46 +192,34 @@ ritem_longest_rhs (void)
 }
 
 
-/*----------------------------------------------------------------.
-| Print the grammar's rules numbers from BEGIN (inclusive) to END |
-| (exclusive) on OUT under TITLE.                                 |
-`----------------------------------------------------------------*/
-
-static inline void
-blanks_print (unsigned n, FILE *out)
-{
-  for (/* Nothing*/; n > 0; --n)
-    fputc (' ', out);
-}
+/*-----------------------------------------------------------------.
+| Print the grammar's rules that match FILTER on OUT under TITLE.  |
+`-----------------------------------------------------------------*/
 
 void
 grammar_rules_partial_print (FILE *out, const char *title,
-			     rule_number_t begin, rule_number_t end)
+			     rule_filter_t filter)
 {
   int r;
-  symbol_t *last_lhs = NULL;
+  bool first = TRUE;
+  symbol_t *previous_lhs = NULL;
 
   /* rule # : LHS -> RHS */
-  fprintf (out, "%s\n\n", title);
-  for (r = begin; r < end; r++)
+  for (r = 0; r < nrules + nuseless_productions; r++)
     {
-      if (last_lhs && last_lhs != rules[r].lhs)
+      if (filter && !filter (&rules[r]))
+	continue;
+      if (first)
+	fprintf (out, "%s\n\n", title);
+      else if (previous_lhs && previous_lhs != rules[r].lhs)
 	fputc ('\n', out);
-
-      fprintf (out, "  %3d ", r - 1);
-      if (last_lhs != rules[r].lhs)
-	{
-	  last_lhs = rules[r].lhs;
-	  fprintf (out, "%s:", symbol_tag_get (last_lhs));
-	}
-      else
-	{
-	  blanks_print (strlen (symbol_tag_get (last_lhs)), out);
-	  fputc ('|', out);
-	}
+      first = FALSE;
+      rule_lhs_print (&rules[r], previous_lhs, out);
       rule_rhs_print (&rules[r], out);
+      previous_lhs = rules[r].lhs;
     }
-  fputs ("\n\n", out);
+  if (!first)
+    fputs ("\n\n", out);
 }
 
 
@@ -184,7 +230,7 @@ grammar_rules_partial_print (FILE *out, const char *title,
 void
 grammar_rules_print (FILE *out)
 {
-  grammar_rules_partial_print (out, _("Grammar"), 1, nrules + 1);
+  grammar_rules_partial_print (out, _("Grammar"), rule_useful_p);
 }
 
 
@@ -210,7 +256,7 @@ grammar_dump (FILE *out, const char *title)
       fprintf (out, "%5d  %5d   %5d  %s\n",
 	       i,
 	       symbols[i]->prec, symbols[i]->assoc,
-	       symbol_tag_get (symbols[i]));
+	       symbols[i]->tag);
     fprintf (out, "\n\n");
   }
 
@@ -218,26 +264,27 @@ grammar_dump (FILE *out, const char *title)
   {
     rule_number_t i;
     fprintf (out, "Num (Prec, Assoc, Useful, Ritem Range) Lhs -> Rhs (Ritem range) [Num]\n");
-    for (i = 1; i < nrules + nuseless_productions + 1; i++)
+    for (i = 0; i < nrules + nuseless_productions; i++)
       {
 	rule_t *rule = &rules[i];
 	item_number_t *r = NULL;
-  	int rhs_count = 0;
+	unsigned int rhs_itemno = rule->rhs - ritem;
+  	unsigned int rhs_count = 0;
 	/* Find the last RHS index in ritems. */
 	for (r = rule->rhs; *r >= 0; ++r)
 	  ++rhs_count;
-	fprintf (out, "%3d (%2d, %2d, %2d, %2d-%2d)   %2d ->",
-		 i - 1,
+	fprintf (out, "%3d (%2d, %2d, %2d, %2u-%2u)   %2d ->",
+		 i,
 		 rule->prec ? rule->prec->prec : 0,
 		 rule->prec ? rule->prec->assoc : 0,
 		 rule->useful,
-		 rule->rhs - ritem,
-		 rule->rhs - ritem + rhs_count - 1,
+		 rhs_itemno,
+		 rhs_itemno + rhs_count - 1,
 		 rule->lhs->number);
 	/* Dumped the RHS. */
 	for (r = rule->rhs; *r >= 0; r++)
 	  fprintf (out, " %3d", *r);
-	fprintf (out, "  [%d]\n", -(*r) - 1);
+	fprintf (out, "  [%d]\n", item_number_as_rule_number (*r));
       }
   }
   fprintf (out, "\n\n");
@@ -245,7 +292,7 @@ grammar_dump (FILE *out, const char *title)
   fprintf (out, "Rules interpreted\n-----------------\n\n");
   {
     rule_number_t r;
-    for (r = 1; r < nrules + nuseless_productions + 1; r++)
+    for (r = 0; r < nrules + nuseless_productions; r++)
       {
 	fprintf (out, "%-5d  ", r);
 	rule_print (&rules[r], out);
@@ -255,11 +302,32 @@ grammar_dump (FILE *out, const char *title)
 }
 
 
+/*------------------------------------------------------------------.
+| Report on STDERR the rules that are not flagged USEFUL, using the |
+| MESSAGE (which can be `useless rule' when invoked after grammar   |
+| reduction, or `never reduced' after conflicts were taken into     |
+| account).                                                         |
+`------------------------------------------------------------------*/
+
+void
+grammar_rules_never_reduced_report (const char *message)
+{
+  rule_number_t r;
+  for (r = 0; r < nrules ; ++r)
+    if (!rules[r].useful)
+      {
+	LOCATION_PRINT (stderr, rules[r].location);
+	fprintf (stderr, ": %s: %s: ",
+		 _("warning"), message);
+	rule_print (&rules[r], stderr);
+      }
+}
+
 void
 grammar_free (void)
 {
   XFREE (ritem);
-  free (rules + 1);
+  free (rules);
   XFREE (token_translations);
   /* Free the symbol table data structure.  */
   symbols_free ();