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/* origin: FreeBSD /usr/src/lib/msun/src/s_asinhf.c */
/*
* Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
#include "libm.h"
static const float
one = 1.0000000000e+00, /* 0x3F800000 */
ln2 = 6.9314718246e-01, /* 0x3f317218 */
huge= 1.0000000000e+30;
float asinhf(float x)
{
float t,w;
int32_t hx,ix;
GET_FLOAT_WORD(hx, x);
ix = hx & 0x7fffffff;
if (ix >= 0x7f800000) /* x is inf or NaN */
return x+x;
if (ix < 0x31800000) { /* |x| < 2**-28 */
/* return x inexact except 0 */
if (huge+x > one)
return x;
}
if (ix > 0x4d800000) { /* |x| > 2**28 */
w = logf(fabsf(x)) + ln2;
} else if (ix > 0x40000000) { /* 2**28 > |x| > 2.0 */
t = fabsf(x);
w = logf(2.0f*t + one/(sqrtf(x*x+one)+t));
} else { /* 2.0 > |x| > 2**-28 */
t = x*x;
w =log1pf(fabsf(x) + t/(one+sqrtf(one+t)));
}
if (hx > 0)
return w;
return -w;
}
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