newlib-cygwin/newlib/libm/common/sf_lround.c

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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__
long int lroundf(float x)
#else
long int lroundf(x)
float x;
#endif
{
__int32_t exponent_less_127;
__uint32_t w;
long int result;
__int32_t sign;
GET_FLOAT_WORD (w, x);
exponent_less_127 = ((w & 0x7f800000) >> 23) - 127;
sign = (w & 0x80000000) != 0 ? -1 : 1;
w &= 0x7fffff;
w |= 0x800000;
if (exponent_less_127 < (8 * sizeof (long int)) - 1)
{
if (exponent_less_127 < 0)
return exponent_less_127 < -1 ? 0 : sign;
else if (exponent_less_127 >= 23)
result = (long int) w << (exponent_less_127 - 23);
else
{
w += 0x400000 >> exponent_less_127;
result = w >> (23 - exponent_less_127);
}
}
else
return (long int) x;
return sign * result;
}
#ifdef _DOUBLE_IS_32BITS
#ifdef __STDC__
long int lround(double x)
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#else
long int lround(x)
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double x;
#endif
{
return (double) lroundf((float) x);
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}
#endif /* defined(_DOUBLE_IS_32BITS) */