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/* w_expf.c -- float version of w_exp.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.
* ====================================================
*/
#ifndef lint
static char rcsid[] = "$FreeBSD$";
#endif
/*
* wrapper expf(x)
*/
#include "math.h"
#include "math_private.h"
static const float
o_threshold= 8.8721679688e+01, /* 0x42b17180 */
u_threshold= -1.0397208405e+02; /* 0xc2cff1b5 */
float
expf(float x) /* wrapper expf */
{
#ifdef _IEEE_LIBM
return __ieee754_expf(x);
#else
float z;
z = __ieee754_expf(x);
if(_LIB_VERSION == _IEEE_) return z;
if(finitef(x)) {
if(x>o_threshold)
/* exp overflow */
return (float)__kernel_standard((double)x,(double)x,106);
else if(x<u_threshold)
/* exp underflow */
return (float)__kernel_standard((double)x,(double)x,107);
}
return z;
#endif
}
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