X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/696f3a9ab60104c656510fd8d47195c98859943d..ca67e7b465996afb3821d6a075c4dc6a7f0f5d52:/usr/src/usr.lib/libF77/pow_di.c

diff --git a/usr/src/usr.lib/libF77/pow_di.c b/usr/src/usr.lib/libF77/pow_di.c
index c4a4628e9b..923bb7f0eb 100644
--- a/usr/src/usr.lib/libF77/pow_di.c
+++ b/usr/src/usr.lib/libF77/pow_di.c
@@ -1,34 +1,33 @@
-double pow_di(ap, bp)
-double *ap;
-long int *bp;
-{
-double pow, x;
-long int n;
+/*
+ * Copyright (c) 1980 Regents of the University of California.
+ * All rights reserved.  The Berkeley software License Agreement
+ * specifies the terms and conditions for redistribution.
+ *
+ *	@(#)pow_di.c	5.3	1/19/88
+ */
 
-pow = 1;
-x = *ap;
-n = *bp;
+double
+pow_di(ap, bp)
+	double *ap;
+	long *bp;
+{
+	register long n = *bp;
+	double y, x = *ap;
 
-if(n != 0)
-	{
-	if(n < 0)
-		{
-		if(x == 0)
-			{
-			return(pow);
-			}
+	if (!n)
+		return((double)1);
+	if (n < 0) {
+		x = (double)1 / x;
 		n = -n;
-		x = 1/x;
-		}
-	for( ; ; )
-		{
-		if(n & 01)
-			pow *= x;
-		if(n >>= 1)
+	}
+	while (!(n&1)) {
+		x *= x;
+		n >>= 1;
+	}
+	for (y = x; --n > 0; y *= x)
+		while (!(n&1)) {
 			x *= x;
-		else
-			break;
+			n >>= 1;
 		}
-	}
-return(pow);
+	return(y);
 }