1 files changed, 81 insertions, 0 deletions
diff --git a/usr/src/lib/libm/common/Q/exp2l.c b/usr/src/lib/libm/common/Q/exp2l.c
new file mode 100644
index 0000000000..7b0814d90a
--- /dev/null
+++ b/usr/src/lib/libm/common/Q/exp2l.c
@@ -0,0 +1,81 @@
+/*
+ * 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 exp2l = __exp2l
+
+#include "libm.h"
+#include "longdouble.h"
+
+/*
+ *	exp2l(x) = 2**x = 2**((x-anint(x))+anint(x))
+ *		 = 2**anint(x)*2**(x-anint(x))
+ *		 = 2**anint(x)*exp((x-anint(x))*ln2)
+ */
+
+#define	TINY	1.0e-20L	/* single: 1e-5, double: 1e-10, quad: 1e-20 */
+#define	OVFLEXP	16400		/* single: 130,  double  1030,  quad: 16400 */
+#define	UNFLEXP	-16520		/* single:-155,  double -1080,  quad:-16520 */
+
+static const long double
+	zero = 0.0L,
+	tiny = TINY * TINY,
+	half = 0.5L,
+	ln2 = 6.931471805599453094172321214581765680755e-0001L,
+	one = 1.0L;
+
+static const int
+	ovflexp = OVFLEXP,
+	unflexp = UNFLEXP;
+
+long double
+exp2l(long double x) {
+	long double t;
+
+	if (!finitel(x)) {
+		if (isnanl(x) || x > zero)
+			return (x + x);
+		else
+			return (zero);
+	}
+	t = fabsl(x);
+	if (t < half) {
+		if (t < tiny)
+			return (one + x);
+		else
+			return (expl(ln2 * x));
+	}
+	t = anintl(x);
+	if (t < ovflexp) {
+		if (t >= unflexp)
+			return (scalbnl(expl(ln2 * (x - t)), (int) t));
+		else
+			return (scalbnl(one, unflexp));	/* underflow */
+	} else
+		return (scalbnl(one, ovflexp));	/* overflow  */
+}