mirror of
https://github.com/QB64Official/qb64.git
synced 2024-09-12 17:50:19 +00:00
159 lines
5.8 KiB
C
159 lines
5.8 KiB
C
/* IEEE floating point support declarations, for GDB, the GNU Debugger.
|
|
Copyright (C) 1991-2018 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., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
|
|
|
|
#if !defined (FLOATFORMAT_H)
|
|
#define FLOATFORMAT_H 1
|
|
|
|
#include "ansidecl.h"
|
|
|
|
#ifdef __cplusplus
|
|
extern "C" {
|
|
#endif
|
|
|
|
/* 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,
|
|
|
|
/* VAX byte order. Little endian byte order with 16-bit words. The
|
|
following example is an illustration of the byte order only; VAX
|
|
doesn't have a fully IEEE compliant floating-point format.
|
|
EX: 1.2345678e10 => 80 c5 00 00 06 42 e0 fe */
|
|
floatformat_vax
|
|
};
|
|
|
|
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;
|
|
/* Bias added to a "true" exponent to form the biased exponent. It
|
|
is intentionally signed as, otherwize, -exp_bias can turn into a
|
|
very large number (e.g., given the exp_bias of 0x3fff and a 64
|
|
bit long, the equation (long)(1 - exp_bias) evaluates to
|
|
4294950914) instead of -16382). */
|
|
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;
|
|
|
|
/* Validator method. */
|
|
int (*is_valid) (const struct floatformat *fmt, const void *from);
|
|
|
|
/* Is the format actually the sum of two smaller floating point
|
|
formats (IBM long double, as described in
|
|
gcc/config/rs6000/darwin-ldouble-format)? If so, this is the
|
|
smaller format in question, and the fields sign_start through
|
|
intbit describe the first half. If not, this is NULL. */
|
|
const struct floatformat *split_half;
|
|
};
|
|
|
|
/* floatformats for IEEE single and double, big and little endian. */
|
|
|
|
extern const struct floatformat floatformat_ieee_half_big;
|
|
extern const struct floatformat floatformat_ieee_half_little;
|
|
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 VAX. */
|
|
|
|
extern const struct floatformat floatformat_vax_f;
|
|
extern const struct floatformat floatformat_vax_d;
|
|
extern const struct floatformat floatformat_vax_g;
|
|
|
|
/* 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_m88110_harris_ext;
|
|
extern const struct floatformat floatformat_arm_ext_big;
|
|
extern const struct floatformat floatformat_arm_ext_littlebyte_bigword;
|
|
/* IA-64 Floating Point register spilt into memory. */
|
|
extern const struct floatformat floatformat_ia64_spill_big;
|
|
extern const struct floatformat floatformat_ia64_spill_little;
|
|
extern const struct floatformat floatformat_ia64_quad_big;
|
|
extern const struct floatformat floatformat_ia64_quad_little;
|
|
/* IBM long double (double+double). */
|
|
extern const struct floatformat floatformat_ibm_long_double_big;
|
|
extern const struct floatformat floatformat_ibm_long_double_little;
|
|
|
|
/* Convert from FMT to a double.
|
|
FROM is the address of the extended float.
|
|
Store the double in *TO. */
|
|
|
|
extern void
|
|
floatformat_to_double (const struct floatformat *, const void *, double *);
|
|
|
|
/* The converse: convert the double *FROM to FMT
|
|
and store where TO points. */
|
|
|
|
extern void
|
|
floatformat_from_double (const struct floatformat *, const double *, void *);
|
|
|
|
/* Return non-zero iff the data at FROM is a valid number in format FMT. */
|
|
|
|
extern int
|
|
floatformat_is_valid (const struct floatformat *fmt, const void *from);
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif
|
|
|
|
#endif /* defined (FLOATFORMAT_H) */
|