src/neg.c - master - niceSOFT/mpfr

/* mpfr_neg -- change the sign of a floating-point number

Copyright 1999-2001, 2004, 2006-2026 Free Software Foundation, Inc.
Contributed by the Pascaline and Caramba projects, INRIA.

This file is part of the GNU MPFR Library.

The GNU MPFR Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 3 of the License, or (at your
option) any later version.

The GNU MPFR 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 Lesser General Public
License for more details.

You should have received a copy of the GNU Lesser General Public License
along with the GNU MPFR Library; see the file COPYING.LESSER.
If not, see <https://www.gnu.org/licenses/>. */

#include "mpfr-impl.h"

int
mpfr_neg (mpfr_ptr a, mpfr_srcptr b, mpfr_rnd_t rnd_mode)
{
  if (MPFR_UNLIKELY(a != b))
    return mpfr_set4 (a, b, rnd_mode, -MPFR_SIGN(b));
  else
    {
      MPFR_CHANGE_SIGN (a);
      if (MPFR_UNLIKELY (MPFR_IS_NAN (b)))
        MPFR_RET_NAN;
      else
        MPFR_RET (0);
    }
}