/* auxiliary data to generate special IEEE floats (NaN, +Inf, -Inf)

Copyright 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
Contributed by the Arenaire and Cacao projects, INRIA.

This file is part of the GNU MPFR Library.

The GNU MPFR 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 3 of the License, or (at your
option) any later version.

The GNU MPFR 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 MPFR Library; see the file COPYING.LESSER.  If not, see
http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */

/* "double" NaN and infinities are written as explicit bytes to be sure of
   getting what we want, and to be sure of not depending on libm.

   Could use 4-byte "float" values and let the code convert them, but it
   seems more direct to give exactly what we want.  Certainly for gcc 3.0.2
   on alphaev56-unknown-freebsd4.3 the NaN must be 8-bytes, since that
   compiler+system was seen incorrectly converting from a "float" NaN.  */

#if _GMP_IEEE_FLOATS

/* The "d" field guarantees alignment to a suitable boundary for a double.
   Could use a union instead, if we checked the compiler supports union
   initializers.  */
struct dbl_bytes {
  unsigned char b[8];
  double d;
};

#define MPFR_DBL_INFP  (* (const double *) dbl_infp.b)
#define MPFR_DBL_INFM  (* (const double *) dbl_infm.b)
#define MPFR_DBL_NAN   (* (const double *) dbl_nan.b)

#if HAVE_DOUBLE_IEEE_LITTLE_ENDIAN
static const struct dbl_bytes dbl_infp =
  { { 0, 0, 0, 0, 0, 0, 0xF0, 0x7F }, 0.0 };
static const struct dbl_bytes dbl_infm =
  { { 0, 0, 0, 0, 0, 0, 0xF0, 0xFF }, 0.0 };
static const struct dbl_bytes dbl_nan  =
  { { 0, 0, 0, 0, 0, 0, 0xF8, 0x7F }, 0.0 };
#endif
#if HAVE_DOUBLE_IEEE_LITTLE_SWAPPED
static const struct dbl_bytes dbl_infp =
  { { 0, 0, 0xF0, 0x7F, 0, 0, 0, 0 }, 0.0 };
static const struct dbl_bytes dbl_infm =
  { { 0, 0, 0xF0, 0xFF, 0, 0, 0, 0 }, 0.0 };
static const struct dbl_bytes dbl_nan  =
  { { 0, 0, 0xF8, 0x7F, 0, 0, 0, 0 }, 0.0 };
#endif
#if HAVE_DOUBLE_IEEE_BIG_ENDIAN
static const struct dbl_bytes dbl_infp =
  { { 0x7F, 0xF0, 0, 0, 0, 0, 0, 0 }, 0.0 };
static const struct dbl_bytes dbl_infm =
  { { 0xFF, 0xF0, 0, 0, 0, 0, 0, 0 }, 0.0 };
static const struct dbl_bytes dbl_nan  =
  { { 0x7F, 0xF8, 0, 0, 0, 0, 0, 0 }, 0.0 };
#endif

#else /* _GMP_IEEE_FLOATS */

#define MPFR_DBL_INFP DBL_POS_INF
#define MPFR_DBL_INFM DBL_NEG_INF
#define MPFR_DBL_NAN DBL_NAN

#endif /* _GMP_IEEE_FLOATS */