sysdeps/libm-ieee754/s_fpclassifyl.c

   1 /* Return classification value corresponding to argument.
   2    Copyright (C) 1997 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
   5    Fixed by Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>.
   6
   7    The GNU C Library is free software; you can redistribute it and/or
   8    modify it under the terms of the GNU Library General Public License as
   9    published by the Free Software Foundation; either version 2 of the
  10    License, or (at your option) any later version.
  11
  12    The GNU C Library is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    Library General Public License for more details.
  16
  17    You should have received a copy of the GNU Library General Public
  18    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  19    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20    Boston, MA 02111-1307, USA.  */
  21
  22 #include <math.h>
  23
  24 #include "math_private.h"
  25
  26
  27 int
  28 __fpclassifyl (long double x)
  29 {
  30   u_int32_t ex, hx, lx, m;
  31   int retval = FP_NORMAL;
  32
  33   GET_LDOUBLE_WORDS (ex, hx, lx, x);
  34   m = (hx & 0x7fffffff) | lx;
  35   ex &= 0x7fff;
  36   if ((ex | m) == 0)
  37     retval = FP_ZERO;
  38   else if (ex == 0 && (hx & 0x80000000) == 0)
  39     retval = FP_SUBNORMAL;
  40   else if (ex == 0x7fff)
  41     retval = m != 0 ? FP_NAN : FP_INFINITE;
  42
  43   return retval;
  44 }