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
141
142
143
144
145
146
147
148
149
150
|
/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* from: @(#)npx.h 5.3 (Berkeley) 1/18/91
* $FreeBSD$
*/
/*
* 287/387 NPX Coprocessor Data Structures and Constants
* W. Jolitz 1/90
*/
#ifndef _MACHINE_NPX_H_
#define _MACHINE_NPX_H_
#include <machine/globals.h>
/* Environment information of floating point unit */
struct env87 {
long en_cw; /* control word (16bits) */
long en_sw; /* status word (16bits) */
long en_tw; /* tag word (16bits) */
long en_fip; /* floating point instruction pointer */
u_short en_fcs; /* floating code segment selector */
u_short en_opcode; /* opcode last executed (11 bits ) */
long en_foo; /* floating operand offset */
long en_fos; /* floating operand segment selector */
};
/* Contents of each floating point accumulator */
struct fpacc87 {
#ifdef dontdef /* too unportable */
u_long fp_mantlo; /* mantissa low (31:0) */
u_long fp_manthi; /* mantissa high (63:32) */
int fp_exp:15; /* exponent */
int fp_sgn:1; /* mantissa sign */
#else
u_char fp_bytes[10];
#endif
};
/* Floating point context */
struct save87 {
struct env87 sv_env; /* floating point control/status */
struct fpacc87 sv_ac[8]; /* accumulator contents, 0-7 */
u_long sv_ex_sw; /* status word for last exception */
/*
* Bogus padding for emulators. Emulators should use their own
* struct and arrange to store into this struct (ending here)
* before it is inspected for ptracing or for core dumps. Some
* emulators overwrite the whole struct. We have no good way of
* knowing how much padding to leave. Leave just enough for the
* GPL emulator's i387_union (176 bytes total).
*/
u_char sv_pad[64]; /* padding; used by emulators */
};
/* Intel prefers long real (53 bit) precision */
#define __iBCS_NPXCW__ 0x262
/* wfj prefers temporary real (64 bit) precision */
#define __386BSD_NPXCW__ 0x362
/*
* bde prefers 53 bit precision and all exceptions masked.
*
* The standard control word from finit is 0x37F, giving:
*
* round to nearest
* 64-bit precision
* all exceptions masked.
*
* Now I want:
*
* affine mode for 287's (if they work at all) (1 in bitfield 1<<12)
* 53-bit precision (2 in bitfield 3<<8)
* overflow exception unmasked (0 in bitfield 1<<3)
* zero divide exception unmasked (0 in bitfield 1<<2)
* invalid-operand exception unmasked (0 in bitfield 1<<0).
*
* 64-bit precision often gives bad results with high level languages
* because it makes the results of calculations depend on whether
* intermediate values are stored in memory or in FPU registers.
*
* The "Intel" and wfj control words have:
*
* underflow exception unmasked (0 in bitfield 1<<4)
*
* but that causes an unexpected exception in the test program 'paranoia'
* and makes denormals useless (DBL_MIN / 2 underflows). It doesn't make
* a lot of sense to trap underflow without trapping denormals.
*
* Later I will want the IEEE default of all exceptions masked. See the
* 0.0 math manpage for why this is better. The 0.1 math manpage is empty.
*/
#define __BDE_NPXCW__ 0x1272
#define __BETTER_BDE_NPXCW__ 0x127f
#ifdef __BROKEN_NPXCW__
#ifdef __FreeBSD__
#define __INITIAL_NPXCW__ __386BSD_NPXCW__
#else
#define __INITIAL_NPXCW__ __iBCS_NPXCW__
#endif
#else
#define __INITIAL_NPXCW__ __BDE_NPXCW__
#endif
#ifdef KERNEL
#ifndef npxproc
extern struct proc *npxproc;
#endif
int npxdna __P((void));
void npxexit __P((struct proc *p));
void npxinit __P((int control));
void npxsave __P((struct save87 *addr));
#endif
#endif /* !_MACHINE_NPX_H_ */
|
