math/s_fdim_template.c

   1 /* Return positive difference between arguments.
   2    Copyright (C) 1997-2023 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <https://www.gnu.org/licenses/>.  */
  18
  19 #include <errno.h>
  20 #include <math.h>
  21 #include <math-narrow-eval.h>
  22
  23 FLOAT
  24 M_DECL_FUNC (__fdim) (FLOAT x, FLOAT y)
  25 {
  26   if (islessequal (x, y))
  27     return 0;
  28
  29   FLOAT r = math_narrow_eval (x - y);
  30   if (isinf (r) && !isinf (x) && !isinf (y))
  31     __set_errno (ERANGE);
  32
  33   return r;
  34 }
  35 declare_mgen_alias (__fdim, fdim);