sysdeps/ieee754/flt-32/s_nextupf.c

   1 /* Return the least floating-point number greater than X.
   2    Copyright (C) 2016-2019 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 <float.h>
  20 #include <math.h>
  21 #include <math_private.h>
  22 #include <libm-alias-float.h>
  23
  24 /* Return the least floating-point number greater than X.  */
  25 float
  26 __nextupf (float x)
  27 {
  28   int32_t hx, ix;
  29
  30   GET_FLOAT_WORD (hx, x);
  31   ix = hx & 0x7fffffff;
  32   if (ix == 0)
  33     return FLT_TRUE_MIN;
  34   if (ix > 0x7f800000)          /* x is nan.  */
  35     return x + x;
  36   if (hx >= 0)
  37     {                           /* x > 0.  */
  38       if (isinf (x))
  39         return x;
  40       hx += 1;
  41     }
  42   else
  43     hx -= 1;
  44   SET_FLOAT_WORD (x, hx);
  45   return x;
  46 }
  47
  48 libm_alias_float (__nextup, nextup)