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#include "libm.h" // for ldshape, ldshape::(anonymous), FORCE_EVAL
#include <float.h> // for LDBL_MANT_DIG, LDBL_MAX_EXP, LDBL_EPSILON
#include <math.h> // for ceill
#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
long double ceill(long double x)
{
return ceil(x);
}
#elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
static const long double toint = 1 / LDBL_EPSILON;
long double ceill(long double x)
{
union ldshape u = { x };
int e = u.i.se & 0x7fff;
long double y;
if (e >= 0x3fff + LDBL_MANT_DIG - 1 || x == 0)
return x;
/* y = int(x) - x, where int(x) is an integer neighbor of x */
if (u.i.se >> 15)
y = x - toint + toint - x;
else
y = x + toint - toint - x;
/* special case because of non-nearest rounding modes */
if (e <= 0x3fff - 1) {
FORCE_EVAL(y);
return u.i.se >> 15 ? -0.0 : 1;
}
if (y < 0)
return x + y + 1;
return x + y;
}
#endif
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