1 files changed, 123 insertions, 0 deletions
diff --git a/usr.bin/yacc/warshall.c b/usr.bin/yacc/warshall.c
new file mode 100644
index 0000000..bdcc6e4
--- /dev/null
+++ b/usr.bin/yacc/warshall.c
@@ -0,0 +1,123 @@
+/*
+ * Copyright (c) 1989 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Robert Paul Corbett.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 4. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if 0
+#ifndef lint
+static char sccsid[] = "@(#)warshall.c	5.4 (Berkeley) 5/24/93";
+#endif
+#endif
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "defs.h"
+
+static void transitive_closure(unsigned *, int);
+
+static void
+transitive_closure(unsigned *R, int n)
+{
+    int rowsize;
+    unsigned i;
+    unsigned *rowj;
+    unsigned *rp;
+    unsigned *rend;
+    unsigned *ccol;
+    unsigned *relend;
+    unsigned *cword;
+    unsigned *rowi;
+
+    rowsize = WORDSIZE(n);
+    relend = R + n*rowsize;
+
+    cword = R;
+    i = 0;
+    rowi = R;
+    while (rowi < relend)
+    {
+	ccol = cword;
+	rowj = R;
+
+	while (rowj < relend)
+	{
+	    if (*ccol & (1 << i))
+	    {
+		rp = rowi;
+		rend = rowj + rowsize;
+		while (rowj < rend)
+		    *rowj++ |= *rp++;
+	    }
+	    else
+	    {
+		rowj += rowsize;
+	    }
+
+	    ccol += rowsize;
+	}
+
+	if (++i >= BITS_PER_WORD)
+	{
+	    i = 0;
+	    cword++;
+	}
+
+	rowi += rowsize;
+    }
+}
+
+void
+reflexive_transitive_closure(unsigned *R, int n)
+{
+    int rowsize;
+    unsigned i;
+    unsigned *rp;
+    unsigned *relend;
+
+    transitive_closure(R, n);
+
+    rowsize = WORDSIZE(n);
+    relend = R + n*rowsize;
+
+    i = 0;
+    rp = R;
+    while (rp < relend)
+    {
+	*rp |= (1 << i);
+	if (++i >= BITS_PER_WORD)
+	{
+	    i = 0;
+	    rp++;
+	}
+
+	rp += rowsize;
+    }
+}