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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"
#ifndef _DOUBLE_IS_32BITS
#ifdef __STDC__
long int lround(double x)
#else
long int lround(x)
double x;
#endif
{
__int32_t sign, exponent_less_1023;
/* Most significant word, least significant word. */
__uint32_t msw, lsw;
long int result;
EXTRACT_WORDS(msw, lsw, x);
/* Extract sign. */
sign = ((msw & 0x80000000) ? -1 : 1);
/* Extract exponent field. */
exponent_less_1023 = ((msw & 0x7ff00000) >> 20) - 1023;
msw &= 0x000fffff;
msw |= 0x00100000;
if (exponent_less_1023 < 20)
{
if (exponent_less_1023 < 0)
{
if (exponent_less_1023 < -1)
return 0;
else
return sign;
}
else
{
msw += 0x80000 >> exponent_less_1023;
result = msw >> (20 - exponent_less_1023);
}
}
else if (exponent_less_1023 < (8 * sizeof (long int)) - 1)
{
if (exponent_less_1023 >= 52)
result = ((long int) msw << (exponent_less_1023 - 20)) | (lsw << (exponent_less_1023 - 52));
else
{
unsigned int tmp = lsw + (0x80000000 >> (exponent_less_1023 - 20));
if (tmp < lsw)
++msw;
result = ((long int) msw << (exponent_less_1023 - 20)) | (tmp >> (52 - exponent_less_1023));
}
}
else
/* Result is too large to be represented by a long int. */
return (long int)x;
return sign * result;
}
#endif /* _DOUBLE_IS_32BITS */
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