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, 115 insertions, 0 deletions

diff --git a/usr/src/lib/libm/common/complex/ctanhf.c b/usr/src/lib/libm/common/complex/ctanhf.c
new file mode 100644
index 0000000000..ab67e2dd40
--- /dev/null
+++ b/usr/src/lib/libm/common/complex/ctanhf.c
@@ -0,0 +1,115 @@
+/*
+ * 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 ctanhf = __ctanhf
+
+#include "libm.h"		/* expf/expm1f/fabsf/sincosf/sinf/tanhf */
+#include "complex_wrapper.h"
+
+/* INDENT OFF */
+static const float four = 4.0F, two = 2.0F, one = 1.0F, zero = 0.0F;
+/* INDENT ON */
+
+fcomplex
+ctanhf(fcomplex z) {
+	float r, u, v, t, x, y, S, C;
+	int hx, ix, hy, iy;
+	fcomplex ans;
+
+	x = F_RE(z);
+	y = F_IM(z);
+	hx = THE_WORD(x);
+	ix = hx & 0x7fffffff;
+	hy = THE_WORD(y);
+	iy = hy & 0x7fffffff;
+	x = fabsf(x);
+	y = fabsf(y);
+
+	if (iy == 0) {		/* ctanh(x,0) = (x,0) for x = 0 or NaN */
+		F_RE(ans) = tanhf(x);
+		F_IM(ans) = zero;
+	} else if (iy >= 0x7f800000) {	/* y is inf or NaN */
+		if (ix < 0x7f800000)	/* catanh(finite x,inf/nan) is nan */
+			F_RE(ans) = F_IM(ans) = y - y;
+		else if (ix == 0x7f800000) {	/* x is inf */
+			F_RE(ans) = one;
+			F_IM(ans) = zero;
+		} else {
+			F_RE(ans) = x + y;
+			F_IM(ans) = y - y;
+		}
+	} else if (ix >= 0x41600000) {
+		/*
+		 * |x| > 14 = prec/2 (14,28,34,60)
+		 * ctanh z ~ 1 + i (sin2y)/(exp(2x))
+		 */
+		F_RE(ans) = one;
+		if (iy < 0x7f000000)	/* t = sin(2y) */
+			S = sinf(y + y);
+		else {
+			(void) sincosf(y, &S, &C);
+			S = (S + S) * C;
+		}
+		if (ix >= 0x7f000000) {	/* |x| > max/2 */
+			if (ix >= 0x7f800000) {	/* |x| is inf or NaN */
+				if (ix > 0x7f800000)	/* x is NaN */
+					F_RE(ans) = F_IM(ans) = x + y;
+				else
+					F_IM(ans) = zero * S;	/* x is inf */
+			} else
+				F_IM(ans) = S * expf(-x);	/* underflow */
+		} else
+			F_IM(ans) = (S + S) * expf(-(x + x));
+							/* 2 sin 2y / exp(2x) */
+	} else {
+		/* INDENT OFF */
+		/*
+		 *                        t*t+2t
+		 *    ctanh z = ---------------------------
+		 *               t*t+[4(t+1)(cos y)](cos y)
+		 *
+		 *                  [4(t+1)(cos y)]*(sin y)
+		 *              i --------------------------
+		 *                t*t+[4(t+1)(cos y)](cos y)
+		 */
+		/* INDENT ON */
+		(void) sincosf(y, &S, &C);
+		t = expm1f(x + x);
+		r = (four * C) * (t + one);
+		u = t * t;
+		v = one / (u + r * C);
+		F_RE(ans) = (u + two * t) * v;
+		F_IM(ans) = (r * S) * v;
+	}
+	if (hx < 0)
+		F_RE(ans) = -F_RE(ans);
+	if (hy < 0)
+		F_IM(ans) = -F_IM(ans);
+	return (ans);
+}