sysdeps/i386/i686/fpu/s_fmaxf.S

   1 /* Compute maximum of two numbers, regarding NaN as missing argument.
   2    Copyright (C) 1997-2021 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 <sysdep.h>
  21 #include <libm-alias-float.h>
  22
  23         .text
  24 ENTRY(__fmaxf)
  25         flds    4(%esp)         // x
  26         flds    8(%esp)         // x : y
  27
  28         fucomi  %st(0), %st
  29         fcmovu  %st(1), %st     // now %st contains y if not NaN, x otherwise
  30
  31         fxch
  32
  33         fucomi  %st(1), %st
  34         fcmovb  %st(1), %st
  35
  36         fstp    %st(1)
  37
  38         ret
  39 END(__fmaxf)
  40 libm_alias_float (__fmax, fmax)