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/*
* ====================================================
* 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 "fdlibm.h"
#ifdef __STDC__
float truncf(float x)
#else
float truncf(x)
float x;
#endif
{
__int32_t signbit, w, exponent_less_127;
GET_FLOAT_WORD(w,x);
/* Extract sign bit. */
signbit = w & 0x80000000;
/* Extract exponent field. */
exponent_less_127 = ((w & 0x7f800000) >> 23) - 127;
if (exponent_less_127 < 23)
{
if (exponent_less_127 < 0)
{
/* -1 < x < 1, so result is +0 or -0. */
SET_FLOAT_WORD(x, signbit);
}
else
{
SET_FLOAT_WORD(x, signbit | (w & ~(0x007fffff >> exponent_less_127)));
}
}
else
{
if (exponent_less_127 == 255)
/* x is NaN or infinite. */
return x + x;
/* All bits in the fraction field are relevant. */
}
return x;
}
#ifdef _DOUBLE_IS_32BITS
#ifdef __STDC__
double trunc(double x)
#else
double trunc(x)
double x;
#endif
{
return (double) truncf((float) x);
}
#endif /* defined(_DOUBLE_IS_32BITS) */
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