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
234
235
236
237
|
/*
NetWinder Floating Point Emulator
(c) Rebel.COM, 1998,1999
Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
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, see <http://www.gnu.org/licenses/>.
*/
#include "fpa11.h"
#include "fpopcode.h"
//#include "fpmodule.h"
//#include "fpmodule.inl"
//#include <asm/system.h>
#include <stdio.h>
FPA11* qemufpa = NULL;
CPUARMState* user_registers;
/* Reset the FPA11 chip. Called to initialize and reset the emulator. */
void resetFPA11(void)
{
int i;
FPA11 *fpa11 = GET_FPA11();
/* initialize the register type array */
for (i=0;i<=7;i++)
{
fpa11->fType[i] = typeNone;
}
/* FPSR: set system id to FP_EMULATOR, set AC, clear all other bits */
fpa11->fpsr = FP_EMULATOR | BIT_AC;
/* FPCR: set SB, AB and DA bits, clear all others */
#ifdef MAINTAIN_FPCR
fpa11->fpcr = MASK_RESET;
#endif
}
void SetRoundingMode(const unsigned int opcode)
{
int rounding_mode;
FPA11 *fpa11 = GET_FPA11();
#ifdef MAINTAIN_FPCR
fpa11->fpcr &= ~MASK_ROUNDING_MODE;
#endif
switch (opcode & MASK_ROUNDING_MODE)
{
default:
case ROUND_TO_NEAREST:
rounding_mode = float_round_nearest_even;
#ifdef MAINTAIN_FPCR
fpa11->fpcr |= ROUND_TO_NEAREST;
#endif
break;
case ROUND_TO_PLUS_INFINITY:
rounding_mode = float_round_up;
#ifdef MAINTAIN_FPCR
fpa11->fpcr |= ROUND_TO_PLUS_INFINITY;
#endif
break;
case ROUND_TO_MINUS_INFINITY:
rounding_mode = float_round_down;
#ifdef MAINTAIN_FPCR
fpa11->fpcr |= ROUND_TO_MINUS_INFINITY;
#endif
break;
case ROUND_TO_ZERO:
rounding_mode = float_round_to_zero;
#ifdef MAINTAIN_FPCR
fpa11->fpcr |= ROUND_TO_ZERO;
#endif
break;
}
set_float_rounding_mode(rounding_mode, &fpa11->fp_status);
}
void SetRoundingPrecision(const unsigned int opcode)
{
int rounding_precision;
FPA11 *fpa11 = GET_FPA11();
#ifdef MAINTAIN_FPCR
fpa11->fpcr &= ~MASK_ROUNDING_PRECISION;
#endif
switch (opcode & MASK_ROUNDING_PRECISION)
{
case ROUND_SINGLE:
rounding_precision = 32;
#ifdef MAINTAIN_FPCR
fpa11->fpcr |= ROUND_SINGLE;
#endif
break;
case ROUND_DOUBLE:
rounding_precision = 64;
#ifdef MAINTAIN_FPCR
fpa11->fpcr |= ROUND_DOUBLE;
#endif
break;
case ROUND_EXTENDED:
rounding_precision = 80;
#ifdef MAINTAIN_FPCR
fpa11->fpcr |= ROUND_EXTENDED;
#endif
break;
default: rounding_precision = 80;
}
set_floatx80_rounding_precision(rounding_precision, &fpa11->fp_status);
}
/* Emulate the instruction in the opcode. */
/* ??? This is not thread safe. */
unsigned int EmulateAll(unsigned int opcode, FPA11* qfpa, CPUARMState* qregs)
{
unsigned int nRc = 0;
// unsigned long flags;
FPA11 *fpa11;
// save_flags(flags); sti();
qemufpa=qfpa;
user_registers=qregs;
#if 0
fprintf(stderr,"emulating FP insn 0x%08x, PC=0x%08x\n",
opcode, qregs[REG_PC]);
#endif
fpa11 = GET_FPA11();
if (fpa11->initflag == 0) /* good place for __builtin_expect */
{
resetFPA11();
SetRoundingMode(ROUND_TO_NEAREST);
SetRoundingPrecision(ROUND_EXTENDED);
fpa11->initflag = 1;
}
set_float_exception_flags(0, &fpa11->fp_status);
if (TEST_OPCODE(opcode,MASK_CPRT))
{
//fprintf(stderr,"emulating CPRT\n");
/* Emulate conversion opcodes. */
/* Emulate register transfer opcodes. */
/* Emulate comparison opcodes. */
nRc = EmulateCPRT(opcode);
}
else if (TEST_OPCODE(opcode,MASK_CPDO))
{
//fprintf(stderr,"emulating CPDO\n");
/* Emulate monadic arithmetic opcodes. */
/* Emulate dyadic arithmetic opcodes. */
nRc = EmulateCPDO(opcode);
}
else if (TEST_OPCODE(opcode,MASK_CPDT))
{
//fprintf(stderr,"emulating CPDT\n");
/* Emulate load/store opcodes. */
/* Emulate load/store multiple opcodes. */
nRc = EmulateCPDT(opcode);
}
else
{
/* Invalid instruction detected. Return FALSE. */
nRc = 0;
}
// restore_flags(flags);
if(nRc == 1 && get_float_exception_flags(&fpa11->fp_status))
{
//printf("fef 0x%x\n",float_exception_flags);
nRc = -get_float_exception_flags(&fpa11->fp_status);
}
//printf("returning %d\n",nRc);
return(nRc);
}
#if 0
unsigned int EmulateAll1(unsigned int opcode)
{
switch ((opcode >> 24) & 0xf)
{
case 0xc:
case 0xd:
if ((opcode >> 20) & 0x1)
{
switch ((opcode >> 8) & 0xf)
{
case 0x1: return PerformLDF(opcode); break;
case 0x2: return PerformLFM(opcode); break;
default: return 0;
}
}
else
{
switch ((opcode >> 8) & 0xf)
{
case 0x1: return PerformSTF(opcode); break;
case 0x2: return PerformSFM(opcode); break;
default: return 0;
}
}
break;
case 0xe:
if (opcode & 0x10)
return EmulateCPDO(opcode);
else
return EmulateCPRT(opcode);
break;
default: return 0;
}
}
#endif
|
