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/* origin: FreeBSD /usr/src/lib/msun/src/s_truncf.c */
/*
* ====================================================
* 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.
* ====================================================
*/
/*
* truncf(x)
* Return x rounded toward 0 to integral value
* Method:
* Bit twiddling.
* Exception:
* Inexact flag raised if x not equal to truncf(x).
*/
#include "libm.h"
static const float huge = 1.0e30F;
float truncf(float x)
{
int32_t i0,j0;
uint32_t i;
GET_FLOAT_WORD(i0, x);
j0 = ((i0>>23)&0xff) - 0x7f;
if (j0 < 23) {
if (j0 < 0) { /* |x|<1, return 0*sign(x) */
/* raise inexact if x != 0 */
if (huge+x > 0.0F)
i0 &= 0x80000000;
} else {
i = 0x007fffff>>j0;
if ((i0&i) == 0)
return x; /* x is integral */
/* raise inexact */
if (huge+x > 0.0F)
i0 &= ~i;
}
} else {
if (j0 == 0x80)
return x + x; /* inf or NaN */
return x; /* x is integral */
}
SET_FLOAT_WORD(x, i0);
return x;
}
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