exp2.c revision ddc0e0b53c661f6e439e3b7072b3ef353eadb4af
/*
* 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
* 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.
*/
/* INDENT OFF */
/*
* exp2(x)
* Code by K.C. Ng for SUN 4.0 libm.
* Method :
* exp2(x) = 2**x = 2**((x-anint(x))+anint(x))
* = 2**anint(x)*2**(x-anint(x))
* = 2**anint(x)*exp((x-anint(x))*ln2)
*/
/* INDENT ON */
#include "libm.h"
static const double C[] = {
0.0,
1.0,
0.5,
6.93147180559945286227e-01,
1.0e300,
1.0e-300,
};
#define zero C[0]
#define one C[1]
#define half C[2]
#define ln2 C[3]
#define huge C[4]
#define tiny C[5]
double
exp2(double x) {
double t;
return (zero);
return (x * x);
}
return (t * t);
}
if (hx < 0x3c000000)
return (one + x);
}
k = (int)x;
if (x != (double)k)
}