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diff --git a/usr/src/lib/libm/common/complex/cexp.c b/usr/src/lib/libm/common/complex/cexp.c
new file mode 100644
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+++ b/usr/src/lib/libm/common/complex/cexp.c
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+/*
+ * 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 cexp = __cexp
+
+/* INDENT OFF */
+/*
+ * dcomplex cexp(dcomplex z);
+ *
+ *  x+iy    x
+ * e     = e  (cos(y)+i*sin(y))
+ *
+ * Over/underflow issue
+ * --------------------
+ * exp(x) may be huge but cos(y) or sin(y) may be tiny. So we use
+ * function __k_cexp(x,&n) to return exp(x) = __k_cexp(x,&n)*2**n.
+ * Thus if exp(x+iy) = A + Bi and t = __k_cexp(x,&n), then
+ *         A = t*cos(y)*2**n,   B = t*sin(y)*2**n
+ *
+ * Purge off all exceptional arguments:
+ *	(x,0) --> (exp(x),0)         for all x, include inf and NaN
+ *	(+inf, y) --> (+inf, NaN)    for inf, nan
+ *	(-inf, y) --> (+-0, +-0)     for y = inf, nan
+ *	(x,+-inf/NaN) --> (NaN,NaN)  for finite x
+ * For all other cases, return
+ *	(x,y) --> exp(x)*cos(y)+i*exp(x)*sin(y))
+ *
+ * Algorithm for out of range x and finite y
+ *	1. compute exp(x) in factor form (t=__k_cexp(x,&n))*2**n
+ *	2. compute sincos(y,&s,&c)
+ *	3. compute t*s+i*(t*c), then scale back to 2**n and return.
+ */
+/* INDENT ON */
+
+#include "libm.h"		/* exp/scalbn/sincos/__k_cexp */
+#include "complex_wrapper.h"
+
+static const double zero = 0.0;
+
+dcomplex
+cexp(dcomplex z) {
+	dcomplex ans;
+	double x, y, t, c, s;
+	int n, ix, iy, hx, hy, lx, ly;
+
+	x = D_RE(z);
+	y = D_IM(z);
+	hx = HI_WORD(x);
+	lx = LO_WORD(x);
+	hy = HI_WORD(y);
+	ly = LO_WORD(y);
+	ix = hx & 0x7fffffff;
+	iy = hy & 0x7fffffff;
+	if ((iy | ly) == 0) {	/* y = 0 */
+		D_RE(ans) = exp(x);
+		D_IM(ans) = y;
+	} else if (ISINF(ix, lx)) {	/* x is +-inf */
+		if (hx < 0) {
+			if (iy >= 0x7ff00000) {
+				D_RE(ans) = zero;
+				D_IM(ans) = zero;
+			} else {
+				sincos(y, &s, &c);
+				D_RE(ans) = zero * c;
+				D_IM(ans) = zero * s;
+			}
+		} else {
+			if (iy >= 0x7ff00000) {
+				D_RE(ans) = x;
+				D_IM(ans) = y - y;
+			} else {
+				(void) sincos(y, &s, &c);
+				D_RE(ans) = x * c;
+				D_IM(ans) = x * s;
+			}
+		}
+	} else {
+		(void) sincos(y, &s, &c);
+		if (ix >= 0x40862E42) {	/* |x| > 709.78... ~ log(2**1024) */
+			t = __k_cexp(x, &n);
+			D_RE(ans) = scalbn(t * c, n);
+			D_IM(ans) = scalbn(t * s, n);
+		} else {
+			t = exp(x);
+			D_RE(ans) = t * c;
+			D_IM(ans) = t * s;
+		}
+	}
+	return (ans);
+}