/* Test whether long double value is canonical.  ldbl-96 version.

   Copyright (C) 2016-2018 Free Software Foundation, Inc.

   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or

   modify it under the terms of the GNU Lesser General Public

   License as published by the Free Software Foundation; either

   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,

   but WITHOUT ANY WARRANTY; without even the implied warranty of

   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public

   License along with the GNU C Library; if not, see

   <http://www.gnu.org/licenses/>.  */

#include <float.h>

#include <math.h>

#include <math_private.h>

#include <stdbool.h>

#include <stdint.h>

int

__iscanonicall (long double x)

{

  uint32_t se, i0, i1 __attribute__ ((unused));

  GET_LDOUBLE_WORDS (se, i0, i1, x);

  int32_t ix = se & 0x7fff;

  bool mant_high = (i0 & 0x80000000) != 0;

  if (LDBL_MIN_EXP == -16381)

    /* Intel variant: the high mantissa bit should have a value

       determined by the exponent.  */

    return ix > 0 ? mant_high : !mant_high;

  else

    /* M68K variant: both values of the high bit are valid for the

       greatest and smallest exponents, while other exponents require

       the high bit to be set.  */

    return ix == 0 || ix == 0x7fff || mant_high;

}

libm_hidden_def (__iscanonicall)