X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/d57650a5ff3d9d1202f6d04de1a10e32cee85499..ce4ccb4b11bb3d19681055cc2b732493603d3508:/src/print.c?ds=sidebyside

diff --git a/src/print.c b/src/print.c
index 8693bbbe..76e5f740 100644
--- a/src/print.c
+++ b/src/print.c
@@ -58,6 +58,7 @@ print_core (FILE *out, state_t *state)
   int i;
   item_number_t *sitems = state->items;
   int snritems   = state->nitems;
+  symbol_t *previous_lhs = NULL;
 
   /* Output all the items of a state, not only its kernel.  */
   if (report_flag & report_itemsets)
@@ -67,40 +68,39 @@ print_core (FILE *out, state_t *state)
       snritems = nritemset;
     }
 
-  if (snritems)
-    {
-      for (i = 0; i < snritems; i++)
-	{
-	  item_number_t *sp;
-	  item_number_t *sp1;
-	  int rule;
+  if (!snritems)
+    return;
 
-	  sp1 = sp = ritem + sitems[i];
+  for (i = 0; i < snritems; i++)
+    {
+      item_number_t *sp;
+      item_number_t *sp1;
+      int rule;
 
-	  while (*sp >= 0)
-	    sp++;
+      sp1 = sp = ritem + sitems[i];
 
-	  rule = -(*sp);
-	  fprintf (out, "    %s  ->  ", symbol_tag_get (rules[rule].lhs));
+      while (*sp >= 0)
+	sp++;
 
-	  for (sp = rules[rule].rhs; sp < sp1; sp++)
-	    fprintf (out, "%s ", symbol_tag_get (symbols[*sp]));
+      rule = -(*sp);
 
-	  fputc ('.', out);
+      rule_lhs_print (&rules[rule], previous_lhs, out);
+      previous_lhs = rules[rule].lhs;
 
-	  for (/* Nothing */; *sp >= 0; ++sp)
-	    fprintf (out, " %s", symbol_tag_get (symbols[*sp]));
+      for (sp = rules[rule].rhs; sp < sp1; sp++)
+	fprintf (out, " %s", symbol_tag_get (symbols[*sp]));
+      fputs (" .", out);
+      for (/* Nothing */; *sp >= 0; ++sp)
+	fprintf (out, " %s", symbol_tag_get (symbols[*sp]));
 
-	  /* Display the lookaheads?  */
-	  if (report_flag & report_lookaheads)
-	    state_rule_lookaheads_print (state, &rules[rule], out);
-
-	  fprintf (out, _("   (rule %d)"), rule - 1);
-	  fputc ('\n', out);
-	}
+      /* Display the lookaheads?  */
+      if (report_flag & report_lookaheads)
+	state_rule_lookaheads_print (state, &rules[rule], out);
 
       fputc ('\n', out);
     }
+
+  fputc ('\n', out);
 }
 
 
@@ -108,7 +108,7 @@ static void
 print_shifts (FILE *out, state_t *state)
 {
   int i;
-  shifts *shiftp = state->shifts;
+  shifts_t *shiftp = state->shifts;
 
   for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
     if (!SHIFT_IS_DISABLED (shiftp, i))
@@ -128,7 +128,7 @@ print_shifts (FILE *out, state_t *state)
 static void
 print_errs (FILE *out, state_t *state)
 {
-  errs *errp = state->errs;
+  errs_t *errp = state->errs;
   int i;
 
   for (i = 0; i < errp->nerrs; ++i)
@@ -145,7 +145,7 @@ static void
 print_gotos (FILE *out, state_t *state)
 {
   int i;
-  shifts *shiftp = state->shifts;
+  shifts_t *shiftp = state->shifts;
 
   for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
     /* Skip token shifts.  */;
@@ -165,154 +165,160 @@ print_gotos (FILE *out, state_t *state)
     }
 }
 
-static void
-print_reductions (FILE *out, state_t *state)
+
+/*----------------------------------------------------------.
+| Return the default rule of this STATE if it has one, NULL |
+| otherwise.                                                |
+`----------------------------------------------------------*/
+
+static rule_t *
+state_default_rule_compute (state_t *state)
 {
+  reductions_t *redp = state->reductions;
+  rule_t *default_rule = NULL;
+  int cmax = 0;
   int i;
-  shifts *shiftp = state->shifts;
-  reductions *redp = state->reductions;
-  errs *errp = state->errs;
-  int nodefault = 0;
-
-  if (redp->nreds == 0)
-    return;
 
+  /* No need for a lookahead.  */
   if (state->consistent)
-    {
-      int rule = redp->rules[0];
-      symbol_number_t symbol = rules[rule].lhs->number;
-      fprintf (out, _("    $default\treduce using rule %d (%s)\n\n"),
-	       rule - 1, symbol_tag_get (symbols[symbol]));
-      return;
-    }
+    return &rules[redp->rules[0]];
 
+  /* 1. Each reduction is possibly masked by the lookaheads on which
+     we shift (S/R conflicts)...  */
   bitset_zero (shiftset);
-
-  for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
-    if (!SHIFT_IS_DISABLED (shiftp, i))
-      {
-	/* if this state has a shift for the error token, don't use a
-	   default rule.  */
-	if (SHIFT_IS_ERROR (shiftp, i))
-	  nodefault = 1;
-	bitset_set (shiftset, SHIFT_SYMBOL (shiftp, i));
-      }
-
-  for (i = 0; i < errp->nerrs; i++)
-    if (errp->errs[i])
-      bitset_set (shiftset, errp->errs[i]);
-
-  if (state->nlookaheads == 1 && !nodefault)
+  {
+    shifts_t *shiftp = state->shifts;
+    for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
+      if (!SHIFT_IS_DISABLED (shiftp, i))
+	{
+	  /* If this state has a shift for the error token, don't use a
+	     default rule.  */
+	  if (SHIFT_IS_ERROR (shiftp, i))
+	    return NULL;
+	  bitset_set (shiftset, SHIFT_SYMBOL (shiftp, i));
+	}
+  }
+
+  /* 2. Each reduction is possibly masked by the lookaheads on which
+     we raise an error (due to %nonassoc).  */
+  {
+    errs_t *errp = state->errs;
+    for (i = 0; i < errp->nerrs; i++)
+      if (errp->errs[i])
+	bitset_set (shiftset, errp->errs[i]);
+  }
+
+  for (i = 0; i < state->nlookaheads; ++i)
     {
-      rule_t *default_rule = state->lookaheads_rule[0];
+      int count = 0;
 
-      bitset_and (lookaheadset, state->lookaheads[0], shiftset);
+      /* How many non-masked lookaheads are there for this reduction?
+	 */
+      bitset_andn (lookaheadset, state->lookaheads[i], shiftset);
+      count = bitset_count (lookaheadset);
 
-      for (i = 0; i < ntokens; i++)
-	if (bitset_test (lookaheadset, i))
-	  fprintf (out, _("    %-4s\t[reduce using rule %d (%s)]\n"),
-		   symbol_tag_get (symbols[i]),
-		   default_rule->number - 1,
-		   symbol_tag_get_n (default_rule->lhs, 1));
+      if (count > cmax)
+	{
+	  cmax = count;
+	  default_rule = state->lookaheads_rule[i];
+	}
 
-      fprintf (out, _("    $default\treduce using rule %d (%s)\n\n"),
-	       default_rule->number - 1,
-	       symbol_tag_get (default_rule->lhs));
+      /* 3. And finally, each reduction is possibly masked by previous
+	 reductions (in R/R conflicts, we keep the first reductions).
+	 */
+      bitset_or (shiftset, shiftset, state->lookaheads[i]);
     }
-  else if (state->nlookaheads >= 1)
-    {
-      int cmax = 0;
-      int default_LA = -1;
-      rule_t *default_rule = NULL;
 
-      if (!nodefault)
-	for (i = 0; i < state->nlookaheads; ++i)
-	  {
-	    int count = 0;
-	    int j;
+  return default_rule;
+}
 
-	    bitset_andn (lookaheadset, state->lookaheads[i], shiftset);
 
-	    for (j = 0; j < ntokens; j++)
-	      if (bitset_test (lookaheadset, j))
-		count++;
+/*----------------------------------------------------.
+| Report on OUT the reduction actions of this STATE.  |
+`----------------------------------------------------*/
 
-	    if (count > cmax)
-	      {
-		cmax = count;
-		default_LA = i;
-		default_rule = state->lookaheads_rule[i];
-	      }
+static void
+print_reductions (FILE *out, state_t *state)
+{
+  int i;
+  shifts_t *shiftp = state->shifts;
+  reductions_t *redp = state->reductions;
+  rule_t *default_rule = NULL;
 
-	    bitset_or (shiftset, shiftset, lookaheadset);
-	  }
+  if (redp->nreds == 0)
+    return;
 
-      bitset_zero (shiftset);
+  default_rule = state_default_rule_compute (state);
 
-      for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
-	if (!SHIFT_IS_DISABLED (shiftp, i))
-	  bitset_set (shiftset, SHIFT_SYMBOL (shiftp, i));
+  bitset_zero (shiftset);
+  for (i = 0; i < shiftp->nshifts && SHIFT_IS_SHIFT (shiftp, i); i++)
+    if (!SHIFT_IS_DISABLED (shiftp, i))
+      bitset_set (shiftset, SHIFT_SYMBOL (shiftp, i));
 
-      for (i = 0; i < ntokens; i++)
-	{
-	  int j;
-	  int defaulted = 0;
-	  int count = bitset_test (shiftset, i);
+  for (i = 0; i < ntokens; i++)
+    {
+      int j;
+      int defaulted = 0;
+      int count = bitset_test (shiftset, i);
 
-	  for (j = 0; j < state->nlookaheads; ++j)
-	    if (bitset_test (state->lookaheads[j], i))
+      for (j = 0; j < state->nlookaheads; ++j)
+	if (bitset_test (state->lookaheads[j], i))
+	  {
+	    if (count == 0)
 	      {
-		if (count == 0)
-		  {
-		    if (j != default_LA)
-		      fprintf (out,
-			       _("    %-4s\treduce using rule %d (%s)\n"),
-			       symbol_tag_get (symbols[i]),
-			       state->lookaheads_rule[j]->number - 1,
-			       symbol_tag_get_n (state->lookaheads_rule[j]->lhs, 1));
-		    else
-		      defaulted = 1;
-
-		    count++;
-		  }
+		if (state->lookaheads_rule[j] != default_rule)
+		  fprintf (out,
+			   _("    %-4s\treduce using rule %d (%s)\n"),
+			   symbol_tag_get (symbols[i]),
+			   state->lookaheads_rule[j]->number - 1,
+			   symbol_tag_get_n (state->lookaheads_rule[j]->lhs, 1));
 		else
-		  {
-		    if (defaulted)
-		      fprintf (out,
-			       _("    %-4s\treduce using rule %d (%s)\n"),
-			       symbol_tag_get (symbols[i]),
-			       state->lookaheads_rule[default_LA]->number - 1,
-			       symbol_tag_get_n (state->lookaheads_rule[default_LA]->lhs, 1));
-		    defaulted = 0;
-		    fprintf (out,
-			     _("    %-4s\t[reduce using rule %d (%s)]\n"),
-			     symbol_tag_get (symbols[i]),
-			     state->lookaheads_rule[j]->number - 1,
-			     symbol_tag_get_n (state->lookaheads_rule[j]->lhs, 1));
-		  }
+		  defaulted = 1;
+		count++;
 	      }
-	}
-
-      if (default_LA >= 0)
-	fprintf (out, _("    $default\treduce using rule %d (%s)\n"),
-		 default_rule->number - 1,
-		 symbol_tag_get (default_rule->lhs));
+	    else
+	      {
+		if (defaulted)
+		  fprintf (out,
+			   _("    %-4s\treduce using rule %d (%s)\n"),
+			   symbol_tag_get (symbols[i]),
+			   default_rule->number - 1,
+			   symbol_tag_get_n (default_rule->lhs, 1));
+		defaulted = 0;
+		fprintf (out,
+			 _("    %-4s\t[reduce using rule %d (%s)]\n"),
+			 symbol_tag_get (symbols[i]),
+			 state->lookaheads_rule[j]->number - 1,
+			 symbol_tag_get_n (state->lookaheads_rule[j]->lhs, 1));
+	      }
+	  }
     }
+
+  if (default_rule)
+    fprintf (out, _("    $default\treduce using rule %d (%s)\n"),
+	     default_rule->number - 1,
+	     symbol_tag_get (default_rule->lhs));
+  fputc ('\n', out);
 }
 
 
+/*--------------------------------------------------------------.
+| Report on OUT all the actions (shifts, gotos, reductions, and |
+| explicit erros from %nonassoc) of STATE.                      |
+`--------------------------------------------------------------*/
+
 static void
 print_actions (FILE *out, state_t *state)
 {
-  reductions *redp = state->reductions;
-  shifts *shiftp = state->shifts;
+  reductions_t *redp = state->reductions;
+  shifts_t *shiftp = state->shifts;
 
   if (shiftp->nshifts == 0 && redp->nreds == 0)
     {
       if (state->number == final_state->number)
-       fprintf (out, _("    $default\taccept\n"));
+	fprintf (out, _("    $default\taccept\n"));
       else
-       fprintf (out, _("    NO ACTIONS\n"));
+	fprintf (out, _("    NO ACTIONS\n"));
       return;
     }
 
@@ -322,6 +328,7 @@ print_actions (FILE *out, state_t *state)
   print_gotos (out, state);
 }
 
+
 static void
 print_state (FILE *out, state_t *state)
 {
@@ -354,7 +361,6 @@ static void
 print_grammar (FILE *out)
 {
   symbol_number_t i;
-  item_number_t *rule;
   char buffer[90];
   int column = 0;
 
@@ -366,7 +372,9 @@ print_grammar (FILE *out)
     if (token_translations[i] != undeftoken->number)
       {
 	const char *tag = symbol_tag_get (symbols[token_translations[i]]);
-	int r;
+	rule_number_t r;
+	item_number_t *rhsp;
+
 	buffer[0] = 0;
 	column = strlen (tag);
 	fputs (tag, out);
@@ -374,8 +382,8 @@ print_grammar (FILE *out)
 	sprintf (buffer, " (%d)", i);
 
 	for (r = 1; r < nrules + 1; r++)
-	  for (rule = rules[r].rhs; *rule >= 0; rule++)
-	    if (item_number_as_symbol_number (*rule) == token_translations[i])
+	  for (rhsp = rules[r].rhs; *rhsp >= 0; rhsp++)
+	    if (item_number_as_symbol_number (*rhsp) == token_translations[i])
 	      {
 		END_TEST (65);
 		sprintf (buffer + strlen (buffer), " %d", r - 1);
@@ -390,15 +398,16 @@ print_grammar (FILE *out)
   for (i = ntokens; i < nsyms; i++)
     {
       int left_count = 0, right_count = 0;
-      int r;
+      rule_number_t r;
       const char *tag = symbol_tag_get (symbols[i]);
 
       for (r = 1; r < nrules + 1; r++)
 	{
+	  item_number_t *rhsp;
 	  if (rules[r].lhs->number == i)
 	    left_count++;
-	  for (rule = rules[r].rhs; *rule >= 0; rule++)
-	    if (item_number_as_symbol_number (*rule) == i)
+	  for (rhsp = rules[r].rhs; *rhsp >= 0; rhsp++)
+	    if (item_number_as_symbol_number (*rhsp) == i)
 	      {
 		right_count++;
 		break;
@@ -432,8 +441,9 @@ print_grammar (FILE *out)
 	  sprintf (buffer + strlen (buffer), _(" on right:"));
 	  for (r = 1; r < nrules + 1; r++)
 	    {
-	      for (rule = rules[r].rhs; *rule >= 0; rule++)
-		if (item_number_as_symbol_number (*rule) == i)
+	      item_number_t *rhsp;
+	      for (rhsp = rules[r].rhs; *rhsp >= 0; rhsp++)
+		if (item_number_as_symbol_number (*rhsp) == i)
 		  {
 		    END_TEST (65);
 		    sprintf (buffer + strlen (buffer), " %d", r - 1);