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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 truncl
#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
long double truncl(long double x)
{
return trunc(x);
}
#elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
static const long double toint = 1 / LDBL_EPSILON;
long double truncl(long double x)
{
union ldshape u = { x };
int e = u.i.se & 0x7fff;
int s = u.i.se >> 15;
long double y;
if (e >= 0x3fff + LDBL_MANT_DIG - 1)
return x;
if (e <= 0x3fff - 1) {
FORCE_EVAL(x + 0x1p120f);
return x * 0;
}
/* y = int(|x|) - |x|, where int(|x|) is an integer neighbor of |x| */
if (s)
x = -x;
y = x + toint - toint - x;
if (y > 0)
y -= 1;
x += y;
return s ? -x : x;
}
#endif
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