about summary refs log tree commit diff
path: root/sysdeps/ieee754/float128/ieee754_float128.h
blob: 5e94eb64d348a00c9386b8118e35e553359a18b5 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
/* _Float128 IEEE like macros.
   Copyright (C) 2017-2020 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C 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 2.1 of the License, or (at your option) any later version.

   The GNU C 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 C Library; if not, see
   <https://www.gnu.org/licenses/>.  */
#ifndef _IEEE754_FLOAT128_H
#define _IEEE754_FLOAT128_H

#include <endian.h>
#include <stdint.h>

# if __FLOAT_WORD_ORDER == BIG_ENDIAN
#  define __FLT_EORDER2(t, a, b) t a; t b;
#  define __FLT_EORDER4(t, a, b, c, d) \
			t a; t b; t c; t d;
#  define __FLT_EORDER6(t, a, b, c, d, e, f)  \
			t a; t b; t c; t d; t e; t f;
#  define __FLT_EORDER7(t, a, b, c, d, e, f, g)  \
			t a; t b; t c; t d; t e; t f; t g;
# else
#  define __FLT_EORDER2(t, a, b) \
			t b; t a;
#  define __FLT_EORDER4(t, a, b, c, d) \
			t d; t c; t b; t a;
#  define __FLT_EORDER6(t, a, b, c, d, e, f)  \
			t f; t e; t d; t c; t b; t a;
#  define __FLT_EORDER7(t, a, b, c, d, e, f, g)  \
			t g; t f; t e; t d; t c; t b; t a;
# endif

/* A union which permits us to convert between _Float128 and
   four 32 bit ints or two 64 bit ints.  */

typedef union
{
  _Float128 value;
  struct
  {
    __FLT_EORDER2 (uint64_t, msw, lsw);
  } parts64;
  struct
  {
    __FLT_EORDER4 (uint32_t, w0, w1, w2, w3);
  } parts32;
} ieee854_float128_shape_type;

/* Get two 64 bit ints from a _Float128.  */

# define GET_FLOAT128_WORDS64(ix0,ix1,d)			\
do {								\
  ieee854_float128_shape_type qw_u;				\
  qw_u.value = (d);						\
  (ix0) = qw_u.parts64.msw;					\
  (ix1) = qw_u.parts64.lsw;					\
} while (0)

/* Set a _Float128 from two 64 bit ints.  */

# define SET_FLOAT128_WORDS64(d,ix0,ix1)			\
do {								\
  ieee854_float128_shape_type qw_u;				\
  qw_u.parts64.msw = (ix0);					\
  qw_u.parts64.lsw = (ix1);					\
  (d) = qw_u.value;						\
} while (0)

/* Get the more significant 64 bits of a _Float128 mantissa.  */

# define GET_FLOAT128_MSW64(v,d)				\
do {								\
  ieee854_float128_shape_type sh_u;				\
  sh_u.value = (d);						\
  (v) = sh_u.parts64.msw;					\
} while (0)

/* Set the more significant 64 bits of a _Float128 mantissa from an int.  */

# define SET_FLOAT128_MSW64(d,v)				\
do {								\
  ieee854_float128_shape_type sh_u;				\
  sh_u.value = (d);						\
  sh_u.parts64.msw = (v);					\
  (d) = sh_u.value;						\
} while (0)

/* Get the least significant 64 bits of a _Float128 mantissa.  */

# define GET_FLOAT128_LSW64(v,d)				\
do {								\
  ieee854_float128_shape_type sh_u;				\
  sh_u.value = (d);						\
  (v) = sh_u.parts64.lsw;					\
} while (0)

/* Likewise, some helper macros which are exposed via ieee754.h for
   C99 real types, but not _Float128.  */

union ieee854_float128
  {
    _Float128 d;

    /* This is the IEEE 854 quad-precision format.  */
    struct
      {
	__FLT_EORDER6 (unsigned int, negative:1,
				     exponent:15,
				     mantissa0:16,
				     mantissa1:32,
				     mantissa2:32,
				     mantissa3:32)
      } ieee;

    /* This format makes it easier to see if a NaN is a signalling NaN.  */
    struct
      {
	__FLT_EORDER7 (unsigned int, negative:1,
				     exponent:15,
				     quiet_nan:1,
				     mantissa0:15,
				     mantissa1:32,
				     mantissa2:32,
				     mantissa3:32)
      } ieee_nan;
  };

#define IEEE854_FLOAT128_BIAS 0x3fff /* Added to exponent.  */

#endif