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/* wf_exp.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.
* ====================================================
*/
/*
* wrapper expf(x)
*/
#include "fdlibm.h"
#if __OBSOLETE_MATH
#include <errno.h>
#ifdef __STDC__
static const float
#else
static float
#endif
o_threshold= 8.8721679688e+01, /* 0x42b17180 */
u_threshold= -1.0397208405e+02; /* 0xc2cff1b5 */
#ifdef __STDC__
float expf(float x) /* wrapper expf */
#else
float expf(x) /* wrapper expf */
float x;
#endif
{
#ifdef _IEEE_LIBM
return __ieee754_expf(x);
#else
float z;
struct exception exc;
z = __ieee754_expf(x);
if(_LIB_VERSION == _IEEE_) return z;
if(finitef(x)) {
if(x>o_threshold) {
/* expf(finite) overflow */
#ifndef HUGE_VAL
#define HUGE_VAL inf
double inf = 0.0;
SET_HIGH_WORD(inf,0x7ff00000); /* set inf to infinite */
#endif
exc.type = OVERFLOW;
exc.name = "expf";
exc.err = 0;
exc.arg1 = exc.arg2 = (double)x;
if (_LIB_VERSION == _SVID_)
exc.retval = HUGE;
else
exc.retval = HUGE_VAL;
if (_LIB_VERSION == _POSIX_)
errno = ERANGE;
else if (!matherr(&exc)) {
errno = ERANGE;
}
if (exc.err != 0)
errno = exc.err;
return exc.retval;
} else if(x<u_threshold) {
/* expf(finite) underflow */
exc.type = UNDERFLOW;
exc.name = "expf";
exc.err = 0;
exc.arg1 = exc.arg2 = (double)x;
exc.retval = 0.0;
if (_LIB_VERSION == _POSIX_)
errno = ERANGE;
else if (!matherr(&exc)) {
errno = ERANGE;
}
if (exc.err != 0)
errno = exc.err;
return exc.retval;
}
}
return z;
#endif
}
#ifdef _DOUBLE_IS_32BITS
#ifdef __STDC__
double exp(double x)
#else
double exp(x)
double x;
#endif
{
return (double) expf((float) x);
}
#endif /* defined(_DOUBLE_IS_32BITS) */
#endif /* __OBSOLETE_MATH */
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