Imported Upstream version 20060131HEADupstream/20060131upstreammaster

1 files changed, 69 insertions, 0 deletions

diff --git a/usr/src/libm/src/LD/scalbl.c b/usr/src/libm/src/LD/scalbl.c
new file mode 100644
index 0000000..b49ec2d
--- /dev/null
+++ b/usr/src/libm/src/LD/scalbl.c
@@ -0,0 +1,69 @@
+/*
+ * 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 2006 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident	"@(#)scalbl.c	1.8	06/01/31 SMI"
+
+#pragma weak scalbl = __scalbl
+
+/*
+ * scalbl(x,n): return x * 2**n by manipulating exponent.
+ */
+
+#include "libm.h"
+#include "longdouble.h"
+
+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 */
+#if !defined(__i386)
+	if ((py[0] & 0x7fff0000) == 0x7fff0000)
+		if ((py[0] & 0x80000000) != 0)
+#else
+	if ((py[2] & 0x7fff) == 0x7fff)
+		if ((py[2] & 0x8000) != 0)
+#endif
+			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;
+}