1/* mpfr_neg -- change the sign of a floating-point number
2
3Copyright 1999, 2000, 2001, 2004, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
4Contributed by the AriC and Caramel projects, INRIA.
5
6This file is part of the GNU MPFR Library.
7
8The GNU MPFR Library is free software; you can redistribute it and/or modify
9it under the terms of the GNU Lesser General Public License as published by
10the Free Software Foundation; either version 3 of the License, or (at your
11option) any later version.
12
13The GNU MPFR Library is distributed in the hope that it will be useful, but
14WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
15or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
16License for more details.
17
18You should have received a copy of the GNU Lesser General Public License
19along with the GNU MPFR Library; see the file COPYING.LESSER.  If not, see
20http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
2151 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
22
23#include "mpfr-impl.h"
24
25int
26mpfr_neg (mpfr_ptr a, mpfr_srcptr b, mpfr_rnd_t rnd_mode)
27{
28  if (MPFR_UNLIKELY(a != b))
29    return mpfr_set4 (a, b, rnd_mode, -MPFR_SIGN(b));
30  else if (MPFR_UNLIKELY(MPFR_IS_NAN (b)))
31    {
32      MPFR_RET_NAN;
33    }
34  else
35    {
36      MPFR_CHANGE_SIGN(a);
37      MPFR_RET(0);
38    }
39}
40