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
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
|
/*---------------------------------------------------------------------------+
| fpu_emu.h |
| |
| Copyright (C) 1992,1993,1994,1997 |
| W. Metzenthen, 22 Parker St, Ormond, Vic 3163, |
| Australia. E-mail billm@suburbia.net |
| |
+---------------------------------------------------------------------------*/
#ifndef _FPU_EMU_H_
#define _FPU_EMU_H_
/*
* Define PECULIAR_486 to get a closer approximation to 80486 behaviour,
* rather than behaviour which appears to be cleaner.
* This is a matter of opinion: for all I know, the 80486 may simply
* be complying with the IEEE spec. Maybe one day I'll get to see the
* spec...
*/
#define PECULIAR_486
#ifdef __ASSEMBLY__
#include "fpu_asm.h"
#define Const(x) $##x
#else
#define Const(x) x
#endif
#define EXP_BIAS Const(0)
#define EXP_OVER Const(0x4000) /* smallest invalid large exponent */
#define EXP_UNDER Const(-0x3fff) /* largest invalid small exponent */
#define EXP_WAY_UNDER Const(-0x6000) /* Below the smallest denormal, but
still a 16 bit nr. */
#define EXP_Infinity EXP_OVER
#define EXP_NaN EXP_OVER
#define EXTENDED_Ebias Const(0x3fff)
#define EXTENDED_Emin (-0x3ffe) /* smallest valid exponent */
#define SIGN_POS Const(0)
#define SIGN_NEG Const(0x80)
#define SIGN_Positive Const(0)
#define SIGN_Negative Const(0x8000)
/* Keep the order TAG_Valid, TAG_Zero, TW_Denormal */
/* The following fold to 2 (Special) in the Tag Word */
#define TW_Denormal Const(4) /* De-normal */
#define TW_Infinity Const(5) /* + or - infinity */
#define TW_NaN Const(6) /* Not a Number */
#define TW_Unsupported Const(7) /* Not supported by an 80486 */
#define TAG_Valid Const(0) /* valid */
#define TAG_Zero Const(1) /* zero */
#define TAG_Special Const(2) /* De-normal, + or - infinity,
or Not a Number */
#define TAG_Empty Const(3) /* empty */
#define LOADED_DATA Const(10101) /* Special st() number to identify
loaded data (not on stack). */
/* A few flags (must be >= 0x10). */
#define REV 0x10
#define DEST_RM 0x20
#define LOADED 0x40
#define FPU_Exception Const(0x80000000) /* Added to tag returns. */
#ifndef __ASSEMBLY__
#include "fpu_system.h"
#include <asm/sigcontext.h> /* for struct _fpstate */
#include <asm/math_emu.h>
#include <linux/linkage.h>
/*
#define RE_ENTRANT_CHECKING
*/
#ifdef RE_ENTRANT_CHECKING
extern u_char emulating;
# define RE_ENTRANT_CHECK_OFF emulating = 0
# define RE_ENTRANT_CHECK_ON emulating = 1
#else
# define RE_ENTRANT_CHECK_OFF
# define RE_ENTRANT_CHECK_ON
#endif /* RE_ENTRANT_CHECKING */
#define FWAIT_OPCODE 0x9b
#define OP_SIZE_PREFIX 0x66
#define ADDR_SIZE_PREFIX 0x67
#define PREFIX_CS 0x2e
#define PREFIX_DS 0x3e
#define PREFIX_ES 0x26
#define PREFIX_SS 0x36
#define PREFIX_FS 0x64
#define PREFIX_GS 0x65
#define PREFIX_REPE 0xf3
#define PREFIX_REPNE 0xf2
#define PREFIX_LOCK 0xf0
#define PREFIX_CS_ 1
#define PREFIX_DS_ 2
#define PREFIX_ES_ 3
#define PREFIX_FS_ 4
#define PREFIX_GS_ 5
#define PREFIX_SS_ 6
#define PREFIX_DEFAULT 7
struct address {
unsigned int offset;
unsigned int selector:16;
unsigned int opcode:11;
unsigned int empty:5;
};
struct fpu__reg {
unsigned sigl;
unsigned sigh;
short exp;
};
typedef void (*FUNC)(void);
typedef struct fpu__reg FPU_REG;
typedef void (*FUNC_ST0)(FPU_REG *st0_ptr, u_char st0_tag);
typedef struct { u_char address_size, operand_size, segment; }
overrides;
/* This structure is 32 bits: */
typedef struct { overrides override;
u_char default_mode; } fpu_addr_modes;
/* PROTECTED has a restricted meaning in the emulator; it is used
to signal that the emulator needs to do special things to ensure
that protection is respected in a segmented model. */
#define PROTECTED 4
#define SIXTEEN 1 /* We rely upon this being 1 (true) */
#define VM86 SIXTEEN
#define PM16 (SIXTEEN | PROTECTED)
#define SEG32 PROTECTED
extern u_char const data_sizes_16[32];
#define register_base ((u_char *) registers )
#define fpu_register(x) ( * ((FPU_REG *)( register_base + 10 * (x & 7) )) )
#define st(x) ( * ((FPU_REG *)( register_base + 10 * ((top+x) & 7) )) )
#define STACK_OVERFLOW (FPU_stackoverflow(&st_new_ptr))
#define NOT_EMPTY(i) (!FPU_empty_i(i))
#define NOT_EMPTY_ST0 (st0_tag ^ TAG_Empty)
#define poppop() { FPU_pop(); FPU_pop(); }
/* push() does not affect the tags */
#define push() { top--; }
#define signbyte(a) (((u_char *)(a))[9])
#define getsign(a) (signbyte(a) & 0x80)
#define setsign(a,b) { if (b) signbyte(a) |= 0x80; else signbyte(a) &= 0x7f; }
#define copysign(a,b) { if (getsign(a)) signbyte(b) |= 0x80; \
else signbyte(b) &= 0x7f; }
#define changesign(a) { signbyte(a) ^= 0x80; }
#define setpositive(a) { signbyte(a) &= 0x7f; }
#define setnegative(a) { signbyte(a) |= 0x80; }
#define signpositive(a) ( (signbyte(a) & 0x80) == 0 )
#define signnegative(a) (signbyte(a) & 0x80)
static inline void reg_copy(FPU_REG const *x, FPU_REG *y)
{
*(short *)&(y->exp) = *(const short *)&(x->exp);
*(long long *)&(y->sigl) = *(const long long *)&(x->sigl);
}
#define exponent(x) (((*(short *)&((x)->exp)) & 0x7fff) - EXTENDED_Ebias)
#define setexponentpos(x,y) { (*(short *)&((x)->exp)) = \
((y) + EXTENDED_Ebias) & 0x7fff; }
#define exponent16(x) (*(short *)&((x)->exp))
#define setexponent16(x,y) { (*(short *)&((x)->exp)) = (y); }
#define addexponent(x,y) { (*(short *)&((x)->exp)) += (y); }
#define stdexp(x) { (*(short *)&((x)->exp)) += EXTENDED_Ebias; }
#define isdenormal(ptr) (exponent(ptr) == EXP_BIAS+EXP_UNDER)
#define significand(x) ( ((unsigned long long *)&((x)->sigl))[0] )
/*----- Prototypes for functions written in assembler -----*/
/* extern void reg_move(FPU_REG *a, FPU_REG *b); */
asmlinkage int FPU_normalize(FPU_REG *x);
asmlinkage int FPU_normalize_nuo(FPU_REG *x);
asmlinkage int FPU_u_sub(FPU_REG const *arg1, FPU_REG const *arg2,
FPU_REG *answ, unsigned int control_w, u_char sign,
int expa, int expb);
asmlinkage int FPU_u_mul(FPU_REG const *arg1, FPU_REG const *arg2,
FPU_REG *answ, unsigned int control_w, u_char sign,
int expon);
asmlinkage int FPU_u_div(FPU_REG const *arg1, FPU_REG const *arg2,
FPU_REG *answ, unsigned int control_w, u_char sign);
asmlinkage int FPU_u_add(FPU_REG const *arg1, FPU_REG const *arg2,
FPU_REG *answ, unsigned int control_w, u_char sign,
int expa, int expb);
asmlinkage int wm_sqrt(FPU_REG *n, int dummy1, int dummy2,
unsigned int control_w, u_char sign);
asmlinkage unsigned FPU_shrx(void *l, unsigned x);
asmlinkage unsigned FPU_shrxs(void *v, unsigned x);
asmlinkage unsigned long FPU_div_small(unsigned long long *x, unsigned long y);
asmlinkage int FPU_round(FPU_REG *arg, unsigned int extent, int dummy,
unsigned int control_w, u_char sign);
#ifndef MAKING_PROTO
#include "fpu_proto.h"
#endif
#endif /* __ASSEMBLY__ */
#endif /* _FPU_EMU_H_ */
|
