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glibc  2.9
s_fpclassifyl.c
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00001 /* Return classification value corresponding to argument.
00002    Copyright (C) 1997, 1999, 2002 Free Software Foundation, Inc.
00003    This file is part of the GNU C Library.
00004    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997 and
00005                 Jakub Jelinek <jj@ultra.linux.cz>, 1999.
00006 
00007    The GNU C Library is free software; you can redistribute it and/or
00008    modify it under the terms of the GNU Lesser General Public
00009    License as published by the Free Software Foundation; either
00010    version 2.1 of the License, or (at your option) any later version.
00011 
00012    The GNU C Library is distributed in the hope that it will be useful,
00013    but WITHOUT ANY WARRANTY; without even the implied warranty of
00014    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00015    Lesser General Public License for more details.
00016 
00017    You should have received a copy of the GNU Lesser General Public
00018    License along with the GNU C Library; if not, write to the Free
00019    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
00020    02111-1307 USA.  */
00021 
00022 #include <math.h>
00023 
00024 #include "math_private.h"
00025 
00026 
00027 int
00028 __fpclassifyl (long double x)
00029 {
00030   u_int64_t hx, lx;
00031   int retval = FP_NORMAL;
00032 
00033   GET_LDOUBLE_WORDS64 (hx, lx, x);
00034   lx |= (hx & 0x0000ffffffffffffLL);
00035   hx &= 0x7fff000000000000LL;
00036   if ((hx | lx) == 0)
00037     retval = FP_ZERO;
00038   else if (hx == 0)
00039     retval = FP_SUBNORMAL;
00040   else if (hx == 0x7fff000000000000LL)
00041     retval = lx != 0 ? FP_NAN : FP_INFINITE;
00042 
00043   return retval;
00044 }
00045 libm_hidden_def (__fpclassifyl)