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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;
}