X-Git-Url: https://git.saurik.com/bison.git/blobdiff_plain/ceed8467b7db3615d3c9bfa9f3e5525d54c6a161..002389585a71dfe28525fc0cdf5100c550e40b63:/src/nullable.c?ds=sidebyside

diff --git a/src/nullable.c b/src/nullable.c
index 516fce40..c207924d 100644
--- a/src/nullable.c
+++ b/src/nullable.c
@@ -1,71 +1,74 @@
 /* Part of the bison parser generator,
-   Copyright (C) 1984, 1989 Free Software Foundation, Inc.
+   Copyright 1984, 1989, 2000, 2001 Free Software Foundation, Inc.
 
-This file is part of Bison, the GNU Compiler Compiler.
+   This file is part of Bison, the GNU Compiler Compiler.
 
-Bison is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
-any later version.
+   Bison is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
 
-Bison is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-GNU General Public License for more details.
+   Bison is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
 
-You should have received a copy of the GNU General Public License
-along with Bison; see the file COPYING.  If not, write to
-the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA.  */
+   You should have received a copy of the GNU General Public License
+   along with Bison; see the file COPYING.  If not, write to
+   the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
 
 
-/* set up nullable, a vector saying which nonterminals can expand into
-   the null string.  nullable[i - ntokens] is nonzero if symbol i can
+/* Set up NULLABLE, a vector saying which nonterminals can expand into
+   the null string.  NULLABLE[I - NTOKENS] is nonzero if symbol I can
    do so.  */
 
 #include "system.h"
+#include "getargs.h"
+#include "reader.h"
 #include "types.h"
 #include "gram.h"
-#include "alloc.h"
+#include "nullable.h"
 
+char *nullable = NULL;
 
-char *nullable;
-
-extern void free_nullable PARAMS((void));
-extern void set_nullable PARAMS((void));
+static void
+nullable_print (FILE *out)
+{
+  int i;
+  fputs ("NULLABLE\n", out);
+  for (i = ntokens; i < nsyms; i++)
+    fprintf (out, "\t%s: %s\n", tags[i], nullable[i] ? "yes" : "no");
+  fputs ("\n\n", out);
+}
 
 void
 set_nullable (void)
 {
-  register short *r;
-  register short *s1;
-  register short *s2;
-  register int ruleno;
-  register int symbol;
-  register shorts *p;
+  short *r;
+  short *s1;
+  short *s2;
+  shorts *p;
 
   short *squeue;
   short *rcount;
   shorts **rsets;
   shorts *relts;
-  char any_tokens;
-  short *r1;
 
-#ifdef	TRACE
-  fprintf(stderr, _("Entering set_nullable"));
-#endif
+  if (trace_flag)
+    fprintf (stderr, "Entering set_nullable\n");
 
-  nullable = NEW2(nvars, char) - ntokens;
+  nullable = XCALLOC (char, nvars) - ntokens;
 
-  squeue = NEW2(nvars, short);
+  squeue = XCALLOC (short, nvars);
   s1 = s2 = squeue;
 
-  rcount = NEW2(nrules + 1, short);
-  rsets = NEW2(nvars, shorts *) - ntokens;
+  rcount = XCALLOC (short, nrules + 1);
+  rsets = XCALLOC (shorts *, nvars) - ntokens;
   /* This is said to be more elements than we actually use.
      Supposedly nitems - nrules is enough.
      But why take the risk?  */
-  relts = NEW2(nitems + nvars + 1, shorts);
+  relts = XCALLOC (shorts, nitems + nvars + 1);
   p = relts;
 
   r = ritem;
@@ -73,7 +76,7 @@ set_nullable (void)
     {
       if (*r < 0)
 	{
-	  symbol = rlhs[-(*r++)];
+	  int symbol = rule_table[-(*r++)].lhs;
 	  if (symbol >= 0 && !nullable[symbol])
 	    {
 	      nullable[symbol] = 1;
@@ -82,17 +85,16 @@ set_nullable (void)
 	}
       else
 	{
-	  r1 = r;
-	  any_tokens = 0;
+	  int any_tokens = 0;
+	  int symbol;
+	  short *r1 = r;
 	  for (symbol = *r++; symbol > 0; symbol = *r++)
-	    {
-	      if (ISTOKEN(symbol))
-		any_tokens = 1;
-	    }
+	    if (ISTOKEN (symbol))
+	      any_tokens = 1;
 
 	  if (!any_tokens)
 	    {
-	      ruleno = -symbol;
+	      int ruleno = -symbol;
 	      r = r1;
 	      for (symbol = *r++; symbol > 0; symbol = *r++)
 		{
@@ -111,11 +113,11 @@ set_nullable (void)
       p = rsets[*s1++];
       while (p)
 	{
-	  ruleno = p->value;
+	  int ruleno = p->value;
 	  p = p->next;
 	  if (--rcount[ruleno] == 0)
 	    {
-	      symbol = rlhs[ruleno];
+	      int symbol = rule_table[ruleno].lhs;
 	      if (symbol >= 0 && !nullable[symbol])
 		{
 		  nullable[symbol] = 1;
@@ -125,15 +127,18 @@ set_nullable (void)
 	}
     }
 
-  FREE(squeue);
-  FREE(rcount);
-  FREE(rsets + ntokens);
-  FREE(relts);
+  XFREE (squeue);
+  XFREE (rcount);
+  XFREE (rsets + ntokens);
+  XFREE (relts);
+
+  if (trace_flag)
+    nullable_print (stderr);
 }
 
 
 void
 free_nullable (void)
 {
-  FREE(nullable + ntokens);
+  XFREE (nullable + ntokens);
 }