double
log2(double x) /* wrapper log10 */
{
#ifdef _IEEE_LIBM
return __ieee754_log2(x);
#else
double z;
z = __ieee754_log2(x);
if(_LIB_VERSION == _IEEE_ || isnan(x)) return z;
if(x<=0.0) {
if(x==0.0)
return __kernel_standard(x,x,48); /* log2(0) */
else
return __kernel_standard(x,x,49); /* log2(x<0) */
} else
return z;
#endif
}
/* wrapper log2(x) */
double
__log2 (double x)
{
if (__builtin_expect (islessequal (x, 0.0), 0) && _LIB_VERSION != _IEEE_)
{
if (x == 0.0)
{
feraiseexcept (FE_DIVBYZERO);
return __kernel_standard (x, x, 48); /* log2(0) */
}
else
{
feraiseexcept (FE_INVALID);
return __kernel_standard (x, x, 49); /* log2(x<0) */
}
}
return __ieee754_log2 (x);
}
/* wrapper log2f(x) */
float
log2f (float x)
{
#if defined(__UCLIBC_HAS_FENV__)
if (__builtin_expect (islessequal (x, 0.0f), 0) && _LIB_VERSION != _IEEE_)
{
if (x == 0.0)
{
feraiseexcept (FE_DIVBYZERO);
return __kernel_standard_f (x, x, 148); /* log2(0) */
}
else
{
feraiseexcept (FE_INVALID);
return __kernel_standard_f (x, x, 149); /* log2(x<0) */
}
}
#endif
return (float) __ieee754_log2 ((double) x);
}
