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#include "libm.h"
double modf(double x, double *iptr)
{
union {double f; uint64_t i;} u = {x};
uint64_t mask;
int e = (int)(u.i>>52 & 0x7ff) - 0x3ff;
/* no fractional part */
if (e >= 52) {
*iptr = x;
if (e == 0x400 && u.i<<12 != 0) /* nan */
return x;
u.i &= 1ULL<<63;
return u.f;
}
/* no integral part*/
if (e < 0) {
u.i &= 1ULL<<63;
*iptr = u.f;
return x;
}
mask = -1ULL>>12>>e;
if ((u.i & mask) == 0) {
*iptr = x;
u.i &= 1ULL<<63;
return u.f;
}
u.i &= ~mask;
*iptr = u.f;
return x - u.f;
}
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