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#include <stdint.h>
#include <float.h>
#include <math.h>
#include "internal/libm.h"
#define EPS DBL_EPSILON
static const double toint = 1/EPS;
double floor(double x) {
union {double f; uint64_t i;} u = {x};
int e = u.i >> 52 & 0x7ff;
double y;
if (e >= 0x3ff+52 || x == 0)
return x;
if (u.i >> 63)
y = x - toint + toint - x;
else
y = x + toint - toint - x;
if (e <= 0x3ff-1) {
return u.i >> 63 ? -1 : 0;
}
if (y > 0) {
FORCE_EVAL(y);
return x + y - 1;
}
return x + y;
}
float floorf(float x) {
union {float f; uint32_t i;} u = {x};
int e = (int)(u.i >> 23 & 0xff) - 0x7f;
uint32_t m;
if (e >= 23)
return x;
if (e >= 0) {
m = 0x007fffff >> e;
if ((u.i & m) == 0)
return x;
FORCE_EVAL(x + 0x1p120f);
if (u.i >> 31)
u.i += m;
u.i &= ~m;
} else {
FORCE_EVAL(x + 0x1p120f);
if (u.i >> 31 == 0)
u.i = 0;
else if (u.i << 1)
u.f = -1.0;
}
return u.f;
}
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