gdb/doublest.h

/* Floating point definitions for GDB.

   Copyright (C) 1986-2016 Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#ifndef DOUBLEST_H
#define DOUBLEST_H

struct type;
struct floatformat;

/* Setup definitions for host and target floating point formats.  We need to
   consider the format for `float', `double', and `long double' for both target
   and host.  We need to do this so that we know what kind of conversions need
   to be done when converting target numbers to and from the hosts DOUBLEST
   data type.  */

/* This is used to indicate that we don't know the format of the floating point
   number.  Typically, this is useful for native ports, where the actual format
   is irrelevant, since no conversions will be taking place.  */

#include "floatformat.h"	/* For struct floatformat */

/* Use `long double' if the host compiler supports it.  (Note that this is not
   necessarily any longer than `double'.  On SunOS/gcc, it's the same as
   double.)  This is necessary because GDB internally converts all floating
   point values to the widest type supported by the host.

   There are problems however, when the target `long double' is longer than the
   host's `long double'.  In general, we'll probably reduce the precision of
   any such values and print a warning.  */

#if (defined HAVE_LONG_DOUBLE && defined PRINTF_HAS_LONG_DOUBLE \
     && defined SCANF_HAS_LONG_DOUBLE)
typedef long double DOUBLEST;
# define DOUBLEST_PRINT_FORMAT "Lg"
# define DOUBLEST_SCAN_FORMAT "Lg"
#else
typedef double DOUBLEST;
# define DOUBLEST_PRINT_FORMAT "g"
# define DOUBLEST_SCAN_FORMAT "lg"
/* If we can't scan or print long double, we don't want to use it
   anywhere.  */
# undef HAVE_LONG_DOUBLE
# undef PRINTF_HAS_LONG_DOUBLE
# undef SCANF_HAS_LONG_DOUBLE
#endif

/* Different kinds of floatformat numbers recognized by
   floatformat_classify.  To avoid portability issues, we use local
   values instead of the C99 macros (FP_NAN et cetera).  */
enum float_kind {
  float_nan,
  float_infinite,
  float_zero,
  float_normal,
  float_subnormal
};

extern void floatformat_to_doublest (const struct floatformat *,
				     const void *in, DOUBLEST *out);
extern void floatformat_from_doublest (const struct floatformat *,
				       const DOUBLEST *in, void *out);

extern int floatformat_is_negative (const struct floatformat *,
				    const bfd_byte *);
extern enum float_kind floatformat_classify (const struct floatformat *,
					     const bfd_byte *);
extern const char *floatformat_mantissa (const struct floatformat *,
					 const bfd_byte *);

/* Given TYPE, return its floatformat.  TYPE_FLOATFORMAT() may return
   NULL.  type_floatformat() detects that and returns a floatformat
   based on the type size when FLOATFORMAT is NULL.  */

const struct floatformat *floatformat_from_type (const struct type *type);

/* Return the floatformat's total size in host bytes.  */

extern size_t floatformat_totalsize_bytes (const struct floatformat *fmt);

extern DOUBLEST extract_typed_floating (const void *addr,
					const struct type *type);
extern void store_typed_floating (void *addr, const struct type *type,
				  DOUBLEST val);
extern void convert_typed_floating (const void *from,
				    const struct type *from_type,
                                    void *to, const struct type *to_type);

#endif