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/* lround adapted to be llround for Newlib, 2009 by Craig Howland. */
/*
* ====================================================
* 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 _NEED_FLOAT64
long long int
llround64(__float64 x)
{
__int32_t sign, exponent_less_1023;
/* Most significant word, least significant word. */
__uint32_t msw, lsw;
long 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;
/* exponent_less_1023 in [-1023,1024] */
if (exponent_less_1023 < 20)
{
/* exponent_less_1023 in [-1023,19] */
if (exponent_less_1023 < 0)
{
if (exponent_less_1023 < -1)
return 0;
else
return sign;
}
else
{
/* exponent_less_1023 in [0,19] */
/* shift amt in [0,19] */
msw += 0x80000 >> exponent_less_1023;
/* shift amt in [20,1] */
result = msw >> (20 - exponent_less_1023);
}
}
else if (exponent_less_1023 < (__int32_t) ((8 * sizeof (long long int)) - 1))
{
/* 64bit longlong: exponent_less_1023 in [20,62] */
if (exponent_less_1023 >= 52)
/* 64bit longlong: exponent_less_1023 in [52,62] */
/* 64bit longlong: shift amt in [32,42] */
result = ((long long int) msw << (exponent_less_1023 - 20))
/* 64bit longlong: shift amt in [0,10] */
| (lsw << (exponent_less_1023 - 52));
else
{
/* 64bit longlong: exponent_less_1023 in [20,51] */
unsigned int tmp = lsw
/* 64bit longlong: shift amt in [0,31] */
+ (0x80000000 >> (exponent_less_1023 - 20));
if (tmp < lsw)
++msw;
/* 64bit longlong: shift amt in [0,31] */
result = ((long long int) msw << (exponent_less_1023 - 20))
/* ***64bit longlong: shift amt in [32,1] */
| SAFE_RIGHT_SHIFT (tmp, (52 - exponent_less_1023));
}
}
else
/* Result is too large to be represented by a long long int. */
return (long long int)x;
return sign * result;
}
_MATH_ALIAS_k_d(llround)
#endif /* _NEED_FLOAT64 */
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