1 files changed, 89 insertions, 0 deletions
diff --git a/usr/src/lib/libm/common/C/asinh.c b/usr/src/lib/libm/common/C/asinh.c
new file mode 100644
index 0000000000..6d6b852009
--- /dev/null
+++ b/usr/src/lib/libm/common/C/asinh.c
@@ -0,0 +1,89 @@
+/*
+ * 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 asinh = __asinh
+
+/* INDENT OFF */
+/*
+ * asinh(x)
+ * Method :
+ *	Based on
+ *		asinh(x) = sign(x) * log [ |x| + sqrt(x*x+1) ]
+ *	we have
+ *	asinh(x) := x  if  1+x*x == 1,
+ *		 := sign(x)*(log(x)+ln2)) for large |x|, else
+ *		 := sign(x)*log(2|x|+1/(|x|+sqrt(x*x+1))) if|x| > 2, else
+ *		 := sign(x)*log1p(|x|+x^2/(1+sqrt(1+x^2)))
+ */
+/* INDENT ON */
+
+#include "libm_synonyms.h"	/* __asinh */
+#include "libm_macros.h"
+#include <math.h>
+
+static const double xxx[] = {
+/* one */	1.00000000000000000000e+00,	/* 3FF00000, 00000000 */
+/* ln2 */	6.93147180559945286227e-01,	/* 3FE62E42, FEFA39EF */
+/* huge */	1.00000000000000000000e+300
+};
+#define	one	xxx[0]
+#define	ln2	xxx[1]
+#define	huge	xxx[2]
+
+double
+asinh(double x) {
+	double t, w;
+	int hx, ix;
+
+	hx = ((int *) &x)[HIWORD];
+	ix = hx & 0x7fffffff;
+	if (ix >= 0x7ff00000)
+#if defined(FPADD_TRAPS_INCOMPLETE_ON_NAN)
+		return (ix >= 0x7ff80000 ? x : x + x);
+		/* assumes sparc-like QNaN */
+#else
+		return (x + x);	/* x is inf or NaN */
+#endif
+	if (ix < 0x3e300000) {	/* |x|<2**-28 */
+		if (huge + x > one)
+			return (x);	/* return x inexact except 0 */
+	}
+	if (ix > 0x41b00000) {	/* |x| > 2**28 */
+		w = log(fabs(x)) + ln2;
+	} else if (ix > 0x40000000) {
+		/* 2**28 > |x| > 2.0 */
+		t = fabs(x);
+		w = log(2.0 * t + one / (sqrt(x * x + one) + t));
+	} else {
+		/* 2.0 > |x| > 2**-28 */
+		t = x * x;
+		w = log1p(fabs(x) + t / (one + sqrt(one + t)));
+	}
+	return (hx > 0 ? w : -w);
+}