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/* IEEE floating point support declarations, for GDB, the GNU Debugger.
Copyright (C) 1991, 2000 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 2 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, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
#if !defined (FLOATFORMAT_H)
#define FLOATFORMAT_H 1
#include "ansidecl.h"
/* A floatformat consists of a sign bit, an exponent and a mantissa. Once the
bytes are concatenated according to the byteorder flag, then each of those
fields is contiguous. We number the bits with 0 being the most significant
(i.e. BITS_BIG_ENDIAN type numbering), and specify which bits each field
contains with the *_start and *_len fields. */
/* What is the order of the bytes. */
enum floatformat_byteorders {
/* Standard little endian byte order.
EX: 1.2345678e10 => 00 00 80 c5 e0 fe 06 42 */
floatformat_little,
/* Standard big endian byte order.
EX: 1.2345678e10 => 42 06 fe e0 c5 80 00 00 */
floatformat_big,
/* Little endian byte order but big endian word order.
EX: 1.2345678e10 => e0 fe 06 42 00 00 80 c5 */
floatformat_littlebyte_bigword
};
enum floatformat_intbit { floatformat_intbit_yes, floatformat_intbit_no };
struct floatformat
{
enum floatformat_byteorders byteorder;
unsigned int totalsize; /* Total size of number in bits */
/* Sign bit is always one bit long. 1 means negative, 0 means positive. */
unsigned int sign_start;
unsigned int exp_start;
unsigned int exp_len;
/* Amount added to "true" exponent. 0x3fff for many IEEE extendeds. */
unsigned int exp_bias;
/* Exponent value which indicates NaN. This is the actual value stored in
the float, not adjusted by the exp_bias. This usually consists of all
one bits. */
unsigned int exp_nan;
unsigned int man_start;
unsigned int man_len;
/* Is the integer bit explicit or implicit? */
enum floatformat_intbit intbit;
/* Internal name for debugging. */
const char *name;
};
/* floatformats for IEEE single and double, big and little endian. */
extern const struct floatformat floatformat_ieee_single_big;
extern const struct floatformat floatformat_ieee_single_little;
extern const struct floatformat floatformat_ieee_double_big;
extern const struct floatformat floatformat_ieee_double_little;
/* floatformat for ARM IEEE double, little endian bytes and big endian words */
extern const struct floatformat floatformat_ieee_double_littlebyte_bigword;
/* floatformats for various extendeds. */
extern const struct floatformat floatformat_i387_ext;
extern const struct floatformat floatformat_m68881_ext;
extern const struct floatformat floatformat_i960_ext;
extern const struct floatformat floatformat_m88110_ext;
extern const struct floatformat floatformat_arm_ext;
/* Convert from FMT to a double.
FROM is the address of the extended float.
Store the double in *TO. */
extern void
floatformat_to_double PARAMS ((const struct floatformat *, char *, double *));
/* The converse: convert the double *FROM to FMT
and store where TO points. */
extern void
floatformat_from_double PARAMS ((const struct floatformat *,
double *, char *));
#endif /* defined (FLOATFORMAT_H) */
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