gdb/doublest.h

   1 /* Floating point definitions for GDB.
   2
   3    Copyright (C) 1986-2015 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef DOUBLEST_H
  21 #define DOUBLEST_H
  22
  23 struct type;
  24 struct floatformat;
  25
  26 /* Setup definitions for host and target floating point formats.  We need to
  27    consider the format for `float', `double', and `long double' for both target
  28    and host.  We need to do this so that we know what kind of conversions need
  29    to be done when converting target numbers to and from the hosts DOUBLEST
  30    data type.  */
  31
  32 /* This is used to indicate that we don't know the format of the floating point
  33    number.  Typically, this is useful for native ports, where the actual format
  34    is irrelevant, since no conversions will be taking place.  */
  35
  36 #include "floatformat.h"        /* For struct floatformat */
  37
  38 /* Use `long double' if the host compiler supports it.  (Note that this is not
  39    necessarily any longer than `double'.  On SunOS/gcc, it's the same as
  40    double.)  This is necessary because GDB internally converts all floating
  41    point values to the widest type supported by the host.
  42
  43    There are problems however, when the target `long double' is longer than the
  44    host's `long double'.  In general, we'll probably reduce the precision of
  45    any such values and print a warning.  */
  46
  47 #if (defined HAVE_LONG_DOUBLE && defined PRINTF_HAS_LONG_DOUBLE \
  48      && defined SCANF_HAS_LONG_DOUBLE)
  49 typedef long double DOUBLEST;
  50 # define DOUBLEST_PRINT_FORMAT "Lg"
  51 # define DOUBLEST_SCAN_FORMAT "Lg"
  52 #else
  53 typedef double DOUBLEST;
  54 # define DOUBLEST_PRINT_FORMAT "g"
  55 # define DOUBLEST_SCAN_FORMAT "lg"
  56 /* If we can't scan or print long double, we don't want to use it
  57    anywhere.  */
  58 # undef HAVE_LONG_DOUBLE
  59 # undef PRINTF_HAS_LONG_DOUBLE
  60 # undef SCANF_HAS_LONG_DOUBLE
  61 #endif
  62
  63 /* Different kinds of floatformat numbers recognized by
  64    floatformat_classify.  To avoid portability issues, we use local
  65    values instead of the C99 macros (FP_NAN et cetera).  */
  66 enum float_kind {
  67   float_nan,
  68   float_infinite,
  69   float_zero,
  70   float_normal,
  71   float_subnormal
  72 };
  73
  74 extern void floatformat_to_doublest (const struct floatformat *,
  75                                      const void *in, DOUBLEST *out);
  76 extern void floatformat_from_doublest (const struct floatformat *,
  77                                        const DOUBLEST *in, void *out);
  78
  79 extern int floatformat_is_negative (const struct floatformat *,
  80                                     const bfd_byte *);
  81 extern enum float_kind floatformat_classify (const struct floatformat *,
  82                                              const bfd_byte *);
  83 extern const char *floatformat_mantissa (const struct floatformat *,
  84                                          const bfd_byte *);
  85
  86 /* Given TYPE, return its floatformat.  TYPE_FLOATFORMAT() may return
  87    NULL.  type_floatformat() detects that and returns a floatformat
  88    based on the type size when FLOATFORMAT is NULL.  */
  89
  90 const struct floatformat *floatformat_from_type (const struct type *type);
  91
  92 extern DOUBLEST extract_typed_floating (const void *addr,
  93                                         const struct type *type);
  94 extern void store_typed_floating (void *addr, const struct type *type,
  95                                   DOUBLEST val);
  96 extern void convert_typed_floating (const void *from,
  97                                     const struct type *from_type,
  98                                     void *to, const struct type *to_type);
  99
 100 #endif