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/* origin: FreeBSD /usr/src/lib/msun/src/s_modff.c */
/*
 * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@cygnus.com.
 */
/*
 * ====================================================
 * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
 *
 * Developed at SunPro, a Sun Microsystems, Inc. business.
 * Permission to use, copy, modify, and distribute this
 * software is freely granted, provided that this notice
 * is preserved.
 * ====================================================
 */

#include "libm.h"

static const float one = 1.0;

float modff(float x, float *iptr)
{
	int32_t i0,j0;
	uint32_t i;

	GET_FLOAT_WORD(i0, x);
	j0 = ((i0>>23) & 0xff) - 0x7f;  /* exponent of x */
	if (j0 < 23) {  /* integer part in x */
		if (j0 < 0) {  /* |x| < 1 */
			SET_FLOAT_WORD(*iptr, i0 & 0x80000000);  /* *iptr = +-0 */
			return x;
		}
		i = 0x007fffff >> j0;
		if ((i0&i) == 0) {  /* x is integral */
			uint32_t ix;
			*iptr = x;
			GET_FLOAT_WORD(ix, x);
			SET_FLOAT_WORD(x, ix & 0x80000000);  /* return +-0 */
			return x;
		}
		SET_FLOAT_WORD(*iptr, i0&~i);
		return x - *iptr;
	} else {        /* no fraction part */
		uint32_t ix;
		*iptr = x*one;
		if (x != x)  /* NaN */
			return x;
		GET_FLOAT_WORD(ix, x);
		SET_FLOAT_WORD(x, ix & 0x80000000);  /* return +-0 */
		return x;
	}
}