sysdeps/ieee754/flt-32/s_totalorderf.c

   1 /* Total order operation.  flt-32 version.
   2    Copyright (C) 2016 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    <http://www.gnu.org/licenses/>.  */
  18
  19 #include <math.h>
  20 #include <math_private.h>
  21 #include <stdint.h>
  22
  23 int
  24 totalorderf (float x, float y)
  25 {
  26   int32_t ix, iy;
  27   GET_FLOAT_WORD (ix, x);
  28   GET_FLOAT_WORD (iy, y);
  29 #ifdef HIGH_ORDER_BIT_IS_SET_FOR_SNAN
  30   /* For the preferred quiet NaN convention, this operation is a
  31      comparison of the representations of the arguments interpreted as
  32      sign-magnitude integers.  If both arguments are NaNs, invert the
  33      quiet/signaling bit so comparing that way works.  */
  34   if ((ix & 0x7fffffff) > 0x7f800000 && (iy & 0x7fffffff) > 0x7f800000)
  35     {
  36       ix ^= 0x00400000;
  37       iy ^= 0x00400000;
  38     }
  39 #endif
  40   uint32_t ix_sign = ix >> 31;
  41   uint32_t iy_sign = iy >> 31;
  42   ix ^= ix_sign >> 1;
  43   iy ^= iy_sign >> 1;
  44   return ix <= iy;
  45 }