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| | #include "libm.h"
#ifdef LONG_DOUBLE_IS_BINARY64
long double modfl(long double x, long double *iptr)
{
double d;
long double r;
r = modf(x, &d);
*iptr = d;
return r;
}
#elif defined(LONG_DOUBLE_IS_X87_EXTENDED) || defined(LONG_DOUBLE_IS_BINARY128)
static const long double toint = 1/LDBL_EPSILON;
long double modfl(long double x, long double *iptr)
{
union ldshape u = {x};
int e = (u.i.se & 0x7fff) - 0x3fff;
int s = u.i.se >> 15;
long double absx;
long double y;
/* no fractional part */
if (e >= LDBL_MANT_DIG-1) {
*iptr = x;
if (isnan(x))
return x;
return s ? -0.0 : 0.0;
}
/* no integral part*/
if (e < 0) {
*iptr = s ? -0.0 : 0.0;
return x;
}
/* raises spurious inexact */
absx = s ? -x : x;
y = absx + toint - toint - absx;
if (y == 0) {
*iptr = x;
return s ? -0.0 : 0.0;
}
if (y > 0)
y -= 1;
if (s)
y = -y;
*iptr = x + y;
return -y;
}
#endif
|