glibc/math/w_exp2f.c
2005-12-14 15:06:39 +00:00

33 lines
700 B
C

/*
* wrapper exp2f(x)
*/
#include <float.h>
#include <math.h>
#include "math_private.h"
static const float o_threshold= (float) FLT_MAX_EXP;
static const float u_threshold= (float) (FLT_MIN_EXP - FLT_MANT_DIG - 1);
float
__exp2f (float x) /* wrapper exp2f */
{
#ifdef _IEEE_LIBM
return __ieee754_exp2f (x);
#else
float z;
z = __ieee754_exp2f (x);
if (_LIB_VERSION != _IEEE_ && __finitef (x))
{
if (x > o_threshold)
/* exp2 overflow */
return (float) __kernel_standard ((double) x, (double) x, 144);
else if (x <= u_threshold)
/* exp2 underflow */
return (float) __kernel_standard ((double) x, (double) x, 145);
}
return z;
#endif
}
weak_alias (__exp2f, exp2f)