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/* origin: FreeBSD /usr/src/lib/msun/src/s_rintf.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
TWO23[2] = {
8.3886080000e+06, /* 0x4b000000 */
-8.3886080000e+06, /* 0xcb000000 */
};
float rintf(float x)
{
int32_t i0,j0,sx;
float w,t;
GET_FLOAT_WORD(i0, x);
sx = (i0>>31) & 1;
j0 = ((i0>>23)&0xff) - 0x7f;
if (j0 < 23) {
if (j0 < 0) {
if ((i0&0x7fffffff) == 0)
return x;
STRICT_ASSIGN(float, w, TWO23[sx] + x);
t = w - TWO23[sx];
GET_FLOAT_WORD(i0, t);
SET_FLOAT_WORD(t, (i0&0x7fffffff)|(sx<<31));
return t;
}
STRICT_ASSIGN(float, w, TWO23[sx] + x);
return w - TWO23[sx];
}
if (j0 == 0x80)
return x+x; /* inf or NaN */
return x; /* x is integral */
}
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