libm/s_signbit.c

   1 /* Return nonzero value if number is negative.
   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
   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    <http://www.gnu.org/licenses/>.  */
  19
  20 #include <features.h>
  21 /* Prevent math.h from defining a colliding inline */
  22 #undef __USE_EXTERN_INLINES
  23 #include <math.h>
  24 #include "math_private.h"
  25
  26 int
  27 __signbit (double x)
  28 {
  29   int32_t hx;
  30
  31   GET_HIGH_WORD (hx, x);
  32   return hx & 0x80000000;
  33 }
  34 libm_hidden_def(__signbit)