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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;
}
}
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