math/s_fdim_template.c

   1 /* Return positive difference between arguments.
   2    Copyright (C) 1997-2019 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <https://www.gnu.org/licenses/>.  */
  19
  20 #include <errno.h>
  21 #include <math.h>
  22 #include <math-narrow-eval.h>
  23
  24 FLOAT
  25 M_DECL_FUNC (__fdim) (FLOAT x, FLOAT y)
  26 {
  27   if (islessequal (x, y))
  28     return 0;
  29
  30   FLOAT r = math_narrow_eval (x - y);
  31   if (isinf (r) && !isinf (x) && !isinf (y))
  32     __set_errno (ERANGE);
  33
  34   return r;
  35 }
  36 declare_mgen_alias (__fdim, fdim);