mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-30 19:53:46 +00:00
49 lines
1.0 KiB
C
49 lines
1.0 KiB
C
|
|
/* @(#)w_exp.c 1.4 04/04/22 */
|
|
/*
|
|
* ====================================================
|
|
* Copyright (C) 2004 by Sun Microsystems, Inc. All rights reserved.
|
|
*
|
|
* Permission to use, copy, modify, and distribute this
|
|
* software is freely granted, provided that this notice
|
|
* is preserved.
|
|
* ====================================================
|
|
*/
|
|
|
|
/*
|
|
* wrapper exp(x)
|
|
*/
|
|
|
|
#include "fdlibm.h"
|
|
|
|
#ifdef __STDC__
|
|
static const double
|
|
#else
|
|
static double
|
|
#endif
|
|
o_threshold= 7.09782712893383973096e+02, /* 0x40862E42, 0xFEFA39EF */
|
|
u_threshold= -7.45133219101941108420e+02; /* 0xc0874910, 0xD52D3051 */
|
|
|
|
#ifdef __STDC__
|
|
double exp(double x) /* wrapper exp */
|
|
#else
|
|
double exp(x) /* wrapper exp */
|
|
double x;
|
|
#endif
|
|
{
|
|
#ifdef _IEEE_LIBM
|
|
return __ieee754_exp(x);
|
|
#else
|
|
double z;
|
|
z = __ieee754_exp(x);
|
|
if(_LIB_VERSION == _IEEE_) return z;
|
|
if(finite(x)) {
|
|
if(x>o_threshold)
|
|
return __kernel_standard(x,x,6); /* exp overflow */
|
|
else if(x<u_threshold)
|
|
return __kernel_standard(x,x,7); /* exp underflow */
|
|
}
|
|
return z;
|
|
#endif
|
|
}
|