X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/78ab8f674f0679b38ca8a6353f562c86b1c95055..d04946c717fd1de8a29804bccf7b2e766970b8ae:/src/gram.c

diff --git a/src/gram.c b/src/gram.c
index e6fb7089..74fd5d57 100644
--- a/src/gram.c
+++ b/src/gram.c
@@ -26,30 +26,85 @@
 #include "reduce.h"
 #include "reader.h"
 
-/* comments for these variables are in gram.h  */
+/* Comments for these variables are in gram.h.  */
 
 item_number_t *ritem = NULL;
-int nritems = 0;
+unsigned int nritems = 0;
 
 rule_t *rules = NULL;
-int nrules = 0;
+rule_number_t nrules = 0;
 
 symbol_t **symbols = NULL;
 int nsyms = 0;
 int ntokens = 1;
 int nvars = 0;
 
-token_number_t *token_translations = NULL;
-
-token_number_t start_symbol = 0;
+symbol_number_t *token_translations = NULL;
 
 int max_user_token_number = 256;
 
-int semantic_parser = 0;
-
+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.  |
 `--------------------------------------*/
@@ -65,6 +120,39 @@ rule_rhs_length (rule_t *rule)
 }
 
 
+/*-------------------------------.
+| Print this RULE's RHS on OUT.  |
+`-------------------------------*/
+
+void
+rule_rhs_print (rule_t *rule, FILE *out)
+{
+  if (*rule->rhs >= 0)
+    {
+      item_number_t *r;
+      for (r = rule->rhs; *r >= 0; r++)
+	fprintf (out, " %s", symbols[*r]->tag);
+      fputc ('\n', out);
+    }
+  else
+    {
+      fprintf (out, " /* %s */\n", _("empty"));
+    }
+}
+
+
+/*-------------------------.
+| Print this RULE on OUT.  |
+`-------------------------*/
+
+void
+rule_print (rule_t *rule, FILE *out)
+{
+  fprintf (out, "%s:", rule->lhs->tag);
+  rule_rhs_print (rule, out);
+}
+
+
 /*------------------------.
 | Dump RITEM for traces.  |
 `------------------------*/
@@ -72,14 +160,13 @@ rule_rhs_length (rule_t *rule)
 void
 ritem_print (FILE *out)
 {
-  int i;
+  unsigned int i;
   fputs ("RITEM\n", out);
   for (i = 0; i < nritems; ++i)
     if (ritem[i] >= 0)
-      fprintf (out, "  %s", quotearg_style (escape_quoting_style,
-					    symbols[ritem[i]]->tag));
+      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);
 }
 
@@ -92,11 +179,11 @@ size_t
 ritem_longest_rhs (void)
 {
   int max = 0;
-  int i;
+  rule_number_t r;
 
-  for (i = 1; i < nrules + 1; ++i)
+  for (r = 0; r < nrules; ++r)
     {
-      int length = rule_rhs_length (&rules[i]);
+      int length = rule_rhs_length (&rules[r]);
       if (length > max)
 	max = length;
     }
@@ -105,6 +192,48 @@ ritem_longest_rhs (void)
 }
 
 
+/*-----------------------------------------------------------------.
+| Print the grammar's rules that match FILTER on OUT under TITLE.  |
+`-----------------------------------------------------------------*/
+
+void
+grammar_rules_partial_print (FILE *out, const char *title,
+			     rule_filter_t filter)
+{
+  int r;
+  bool first = true;
+  symbol_t *previous_lhs = NULL;
+
+  /* rule # : LHS -> RHS */
+  for (r = 0; r < nrules + nuseless_productions; r++)
+    {
+      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);
+      first = false;
+      rule_lhs_print (&rules[r], previous_lhs, out);
+      rule_rhs_print (&rules[r], out);
+      previous_lhs = rules[r].lhs;
+    }
+  if (!first)
+    fputs ("\n\n", out);
+}
+
+
+/*------------------------------------------.
+| Print the grammar's useful rules on OUT.  |
+`------------------------------------------*/
+
+void
+grammar_rules_print (FILE *out)
+{
+  grammar_rules_partial_print (out, _("Grammar"), rule_useful_p);
+}
+
+
 /*-------------------.
 | Dump the grammar.  |
 `-------------------*/
@@ -112,52 +241,95 @@ ritem_longest_rhs (void)
 void
 grammar_dump (FILE *out, const char *title)
 {
-  int i;
-  item_number_t *r;
-
   fprintf (out, "%s\n\n", title);
   fprintf (out,
 	   "ntokens = %d, nvars = %d, nsyms = %d, nrules = %d, nritems = %d\n\n",
 	   ntokens, nvars, nsyms, nrules, nritems);
+
+
   fprintf (out, "Variables\n---------\n\n");
-  fprintf (out, "Value  Sprec  Sassoc  Tag\n");
-  for (i = ntokens; i < nsyms; i++)
-    fprintf (out, "%5d  %5d   %5d  %s\n",
-	     i,
-	     symbols[i]->prec, symbols[i]->assoc,
-	     quotearg_style (escape_quoting_style, symbols[i]->tag));
-  fprintf (out, "\n\n");
+  {
+    symbol_number_t i;
+    fprintf (out, "Value  Sprec  Sassoc  Tag\n");
+
+    for (i = ntokens; i < nsyms; i++)
+      fprintf (out, "%5d  %5d   %5d  %s\n",
+	       i,
+	       symbols[i]->prec, symbols[i]->assoc,
+	       symbols[i]->tag);
+    fprintf (out, "\n\n");
+  }
+
   fprintf (out, "Rules\n-----\n\n");
-  fprintf (out, "Num (Prec, Assoc, Useful, Ritem Range) Lhs -> Rhs (Ritem range) [Num]\n");
-  for (i = 1; i < nrules + nuseless_productions + 1; i++)
-    {
-      int rhs_count = 0;
-      /* Find the last RHS index in ritems. */
-      for (r = rules[i].rhs; *r >= 0; ++r)
-	++rhs_count;
-      fprintf (out, "%3d (%2d, %2d, %2d, %2d-%2d)   %2d ->",
-	       i - 1,
-	       rules[i].prec ? rules[i].prec->prec : 0,
-	       rules[i].prec ? rules[i].prec->assoc : 0,
-	       rules[i].useful,
-	       rules[i].rhs - ritem,
-	       rules[i].rhs - ritem + rhs_count - 1,
-	       rules[i].lhs->number);
-      /* Dumped the RHS. */
-      for (r = rules[i].rhs; *r >= 0; r++)
-	fprintf (out, " %3d", *r);
-      fprintf (out, "  [%d]\n", -(*r) - 1);
-    }
+  {
+    rule_number_t i;
+    fprintf (out, "Num (Prec, Assoc, Useful, Ritem Range) Lhs -> Rhs (Ritem range) [Num]\n");
+    for (i = 0; i < nrules + nuseless_productions; i++)
+      {
+	rule_t *rule = &rules[i];
+	item_number_t *r = NULL;
+	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, %2u-%2u)   %2d ->",
+		 i,
+		 rule->prec ? rule->prec->prec : 0,
+		 rule->prec ? rule->prec->assoc : 0,
+		 rule->useful,
+		 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", item_number_as_rule_number (*r));
+      }
+  }
   fprintf (out, "\n\n");
+
   fprintf (out, "Rules interpreted\n-----------------\n\n");
-  for (i = 1; i < nrules + nuseless_productions + 1; i++)
-    {
-      fprintf (out, "%-5d  %s :",
-	       i, 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));
-      fputc ('\n', out);
-    }
+  {
+    rule_number_t r;
+    for (r = 0; r < nrules + nuseless_productions; r++)
+      {
+	fprintf (out, "%-5d  ", r);
+	rule_print (&rules[r], out);
+      }
+  }
   fprintf (out, "\n\n");
 }
+
+
+/*------------------------------------------------------------------.
+| 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);
+  XFREE (token_translations);
+  /* Free the symbol table data structure.  */
+  symbols_free ();
+  free_merger_functions ();
+}