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| | #include "libm.h"
double ceil(double x)
{
union {double f; uint64_t i;} u = {x};
int e = u.i >> 52 & 0x7ff;
double_t y;
if (e >= 0x3ff+52 || x == 0)
return x;
/* y = int(x) - x, where int(x) is an integer neighbor of x */
if (u.i >> 63)
y = (double)(x - 0x1p52) + 0x1p52 - x;
else
y = (double)(x + 0x1p52) - 0x1p52 - x;
/* special case because of non-nearest rounding modes */
if (e <= 0x3ff-1) {
FORCE_EVAL(y);
return u.i >> 63 ? -0.0 : 1;
}
if (y < 0)
return x + y + 1;
return x + y;
}
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