693 Opensource replacement of sunwlibm

Reviewed by: Igor Kozhukhov ikozhukhov@gmail.com
Reviewed by: Keith M Wesolowski <keith.wesolowski@joyent.com>
Reviewed by: Richard Lowe <richlowe@richlowe.net>
Approved by: Dan McDonald <danmcd@omniti.com>

1 files changed, 68 insertions, 0 deletions

diff --git a/usr/src/lib/libm/common/Q/scalbl.c b/usr/src/lib/libm/common/Q/scalbl.c
new file mode 100644
index 0000000000..7346954a95
--- /dev/null
+++ b/usr/src/lib/libm/common/Q/scalbl.c
@@ -0,0 +1,68 @@
+/*
+ * CDDL HEADER START
+ *
+ * The contents of this file are subject to the terms of the
+ * Common Development and Distribution License (the "License").
+ * You may not use this file except in compliance with the License.
+ *
+ * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+ * or http://www.opensolaris.org/os/licensing.
+ * See the License for the specific language governing permissions
+ * and limitations under the License.
+ *
+ * When distributing Covered Code, include this CDDL HEADER in each
+ * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+ * If applicable, add the following below this CDDL HEADER, with the
+ * fields enclosed by brackets "[]" replaced with your own identifying
+ * information: Portions Copyright [yyyy] [name of copyright owner]
+ *
+ * CDDL HEADER END
+ */
+
+/*
+ * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
+ */
+/*
+ * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma weak scalbl = __scalbl
+
+/*
+ * scalbl(x,n): return x * 2^n by manipulating exponent.
+ */
+
+#include "libm.h"
+
+#define	n0	0
+
+long double
+scalbl(long double x, long double fn) {
+	int *py = (int *) &fn, n;
+	long double z;
+
+	if (isnanl(x) || isnanl(fn))
+		return (x * fn);
+
+	/*
+	 * fn is inf or NaN
+	 */
+	if ((py[n0] & 0x7fff0000) == 0x7fff0000) {
+		if ((py[n0] & 0x80000000) != 0)
+			return (x / (-fn));
+		else
+			return (x * fn);
+	}
+	if (rintl(fn) != fn)
+		return ((fn - fn) / (fn - fn));
+	if (fn > 65000.0L)
+		z = scalbnl(x, 65000);
+	else if (-fn > 65000.0L)
+		z = scalbnl(x, -65000);
+	else {
+		n = (int) fn;
+		z = scalbnl(x, n);
+	}
+	return (z);
+}