freebsd-dev/contrib/libgmp/mpf/cmp.c
Mark Murray aa9bc17601 Clean import of libgmp 2.0.2, with only the non-x86 bits removed.
BMakefiles and other bits will follow.

Requested by:	Andrey Chernov
Made world by:	Chuck Robey
1996-10-20 08:49:26 +00:00

115 lines
2.5 KiB
C

/* mpf_cmp -- Compare two floats.
Copyright (C) 1993, 1994, 1996 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 (mpf_srcptr u, mpf_srcptr v)
#else
mpf_cmp (u, v)
mpf_srcptr u;
mpf_srcptr v;
#endif
{
mp_srcptr up, vp;
mp_size_t usize, vsize;
mp_exp_t uexp, vexp;
int cmp;
int usign;
uexp = u->_mp_exp;
vexp = v->_mp_exp;
usize = u->_mp_size;
vsize = v->_mp_size;
/* 1. Are the signs different? */
if ((usize ^ vsize) >= 0)
{
/* U and V are both non-negative or both negative. */
if (usize == 0)
/* vsize >= 0 */
return -(vsize != 0);
if (vsize == 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? */
if (uexp > vexp)
return usign;
if (uexp < vexp)
return -usign;
usize = ABS (usize);
vsize = ABS (vsize);
up = u->_mp_d;
vp = v->_mp_d;
#define STRICT_MPF_NORMALIZATION 0
#if ! STRICT_MPF_NORMALIZATION
/* Ignore zeroes at the low end of U and V. */
while (up[0] == 0)
{
up++;
usize--;
}
while (vp[0] == 0)
{
vp++;
vsize--;
}
#endif
if (usize > vsize)
{
cmp = mpn_cmp (up + usize - vsize, vp, vsize);
if (cmp == 0)
return usign;
}
else if (vsize > usize)
{
cmp = mpn_cmp (up, vp + vsize - usize, usize);
if (cmp == 0)
return -usign;
}
else
{
cmp = mpn_cmp (up, vp, usize);
if (cmp == 0)
return 0;
}
return cmp > 0 ? usign : -usign;
}