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/* mpf_cmp_si -- Compare a float with a signed integer.
Copyright (C) 1993, 1994, 1995 Free Software Foundation, Inc.
This file is part of the GNU MP Library.
The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at your
option) any later version.
The GNU MP Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public
License for more details.
You should have received a copy of the GNU Library General Public License
along with the GNU MP Library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
#include "gmp.h"
#include "gmp-impl.h"
int
#if __STDC__
mpf_cmp_si (mpf_srcptr u, long int vslimb)
#else
mpf_cmp_si (u, vslimb)
mpf_srcptr u;
long int vslimb;
#endif
{
mp_srcptr up;
mp_size_t usize;
mp_exp_t uexp;
int usign;
uexp = u->_mp_exp;
usize = u->_mp_size;
/* 1. Are the signs different? */
if ((usize < 0) == (vslimb < 0)) /* don't use xor, type size may differ */
{
/* U and V are both non-negative or both negative. */
if (usize == 0)
/* vslimb >= 0 */
return -(vslimb != 0);
if (vslimb == 0)
/* usize >= 0 */
return usize != 0;
/* Fall out. */
}
else
{
/* Either U or V is negative, but not both. */
return usize >= 0 ? 1 : -1;
}
/* U and V have the same sign and are both non-zero. */
usign = usize >= 0 ? 1 : -1;
/* 2. Are the exponents different (V's exponent == 1)? */
if (uexp > 1)
return usign;
if (uexp < 1)
return -usign;
usize = ABS (usize);
vslimb = ABS (vslimb);
up = u->_mp_d;
#define STRICT_MPF_NORMALIZATION 0
#if ! STRICT_MPF_NORMALIZATION
/* Ignore zeroes at the low end of U and V. */
while (*up == 0)
{
up++;
usize--;
}
#endif
/* 3. Now, if the number of limbs are different, we have a difference
since we have made sure the trailing limbs are not zero. */
if (usize > 1)
return usign;
/* 4. Compare the mantissas. */
if (*up > vslimb)
return usign;
else if (*up < vslimb)
return -usign;
/* Wow, we got zero even if we tried hard to avoid it. */
return 0;
}
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