forked from KolibriOS/kolibrios
67 lines
1.3 KiB
C
67 lines
1.3 KiB
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.
|
||
|
|
* ====================================================
|
||
|
|
*/
|
||
|
|
|
||
|
|
#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) */
|