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
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
/* $OpenBSD: fpu_aux.c,v 1.1 1996/08/27 10:32:45 downsj Exp $ */
/*
* fpu_aux.c
*
* Code to implement some of the FPU auxiliary instructions.
*
*
* Copyright (C) 1992,1993,1994
* W. Metzenthen, 22 Parker St, Ormond, Vic 3163,
* Australia. E-mail billm@vaxc.cc.monash.edu.au
* All rights reserved.
*
* This copyright notice covers the redistribution and use of the
* FPU emulator developed by W. Metzenthen. It covers only its use
* in the 386BSD, FreeBSD and NetBSD operating systems. Any other
* use is not permitted under this copyright.
*
* 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 include information specifying
* that source code for the emulator is freely available and include
* either:
* a) an offer to provide the source code for a nominal distribution
* fee, or
* b) list at least two alternative methods whereby the source
* can be obtained, e.g. a publically accessible bulletin board
* and an anonymous ftp site from which the software can be
* downloaded.
* 3. All advertising materials specifically mentioning features or use of
* this emulator must acknowledge that it was developed by W. Metzenthen.
* 4. The name of W. Metzenthen may not be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED ``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
* W. METZENTHEN 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.
*
*
* The purpose of this copyright, based upon the Berkeley copyright, is to
* ensure that the covered software remains freely available to everyone.
*
* The software (with necessary differences) is also available, but under
* the terms of the GNU copyleft, for the Linux operating system and for
* the djgpp ms-dos extender.
*
* W. Metzenthen June 1994.
*
*
* $FreeBSD: fpu_aux.c,v 1.4 1995/12/14 09:50:21 phk Exp $
*
*/
#include <sys/param.h>
#include <sys/proc.h>
#include <machine/cpu.h>
#include <machine/pcb.h>
#include <gnu/arch/i386/fpemul/fpu_emu.h>
#include <gnu/arch/i386/fpemul/fpu_system.h>
#include <gnu/arch/i386/fpemul/exception.h>
#include <gnu/arch/i386/fpemul/status_w.h>
static void
fclex(void)
{
status_word &= ~(SW_Backward | SW_Summary | SW_Stack_Fault | SW_Precision |
SW_Underflow | SW_Overflow | SW_Zero_Div | SW_Denorm_Op |
SW_Invalid);
FPU_entry_eip = ip_offset; /* We want no net effect */
}
/* Needs to be externally visible */
void
finit()
{
int r;
control_word = 0x037f;
status_word = 0;
top = 0; /* We don't keep top in the status word
* internally. */
for (r = 0; r < 8; r++) {
regs[r].tag = TW_Empty;
}
FPU_entry_eip = ip_offset = 0;
}
static FUNC finit_table[] = {
Un_impl, Un_impl, fclex, finit, Un_impl, Un_impl, Un_impl, Un_impl
};
void
finit_()
{
(finit_table[FPU_rm]) ();
}
static void
fstsw_ax(void)
{
status_word &= ~SW_Top;
status_word |= (top & 7) << SW_Top_Shift;
*(short *) &FPU_EAX = status_word;
}
static FUNC fstsw_table[] = {
fstsw_ax, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl
};
void
fstsw_()
{
(fstsw_table[FPU_rm]) ();
}
static void
fnop(void)
{
}
static FUNC fp_nop_table[] = {
fnop, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl, Un_impl
};
void
fp_nop()
{
(fp_nop_table[FPU_rm]) ();
}
void
fld_i_()
{
FPU_REG *st_new_ptr;
if (STACK_OVERFLOW) {
stack_overflow();
return;
}
/* fld st(i) */
if (NOT_EMPTY(FPU_rm)) {
reg_move(&st(FPU_rm), st_new_ptr);
push();
} else {
if (control_word & EX_Invalid) {
/* The masked response */
push();
stack_underflow();
} else
EXCEPTION(EX_StackUnder);
}
}
void
fxch_i()
{
/* fxch st(i) */
FPU_REG t;
register FPU_REG *sti_ptr = &st(FPU_rm);
if (FPU_st0_tag == TW_Empty) {
if (sti_ptr->tag == TW_Empty) {
stack_underflow();
stack_underflow_i(FPU_rm);
return;
}
reg_move(sti_ptr, FPU_st0_ptr);
stack_underflow_i(FPU_rm);
return;
}
if (sti_ptr->tag == TW_Empty) {
reg_move(FPU_st0_ptr, sti_ptr);
stack_underflow();
return;
}
reg_move(FPU_st0_ptr, &t);
reg_move(sti_ptr, FPU_st0_ptr);
reg_move(&t, sti_ptr);
}
void
ffree_()
{
/* ffree st(i) */
st(FPU_rm).tag = TW_Empty;
}
void
ffreep()
{
/* ffree st(i) + pop - unofficial code */
st(FPU_rm).tag = TW_Empty;
pop();
}
void
fst_i_()
{
/* fst st(i) */
reg_move(FPU_st0_ptr, &st(FPU_rm));
}
void
fstp_i()
{
/* fstp st(i) */
reg_move(FPU_st0_ptr, &st(FPU_rm));
pop();
}
|
