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*/
1 /*---------------------------------------------------------------------------+
2 | load_store.c |
3 | |
4 | This file contains most of the code to interpret the FPU instructions |
5 | which load and store from user memory. |
6 | |
7 | Copyright (C) 1992,1993 |
8 | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, |
9 | Australia. E-mail apm233m@vaxc.cc.monash.edu.au |
10 | |
11 | |
12 +---------------------------------------------------------------------------*/
13
14 /*---------------------------------------------------------------------------+
15 | Note: |
16 | The file contains code which accesses user memory. |
17 | Emulator static data may change when user memory is accessed, due to |
18 | other processes using the emulator while swapping is in progress. |
19 +---------------------------------------------------------------------------*/
20
21 #include <asm/segment.h>
22
23 #include "fpu_system.h"
24 #include "exception.h"
25 #include "fpu_emu.h"
26 #include "status_w.h"
27 #include "control_w.h"
28
29
30 #define _NONE_ 0 /* FPU_st0_ptr etc not needed */
31 #define _REG0_ 1 /* Will be storing st(0) */
32 #define _PUSH_ 3 /* Need to check for space to push onto stack */
33 #define _null_ 4 /* Function illegal or not implemented */
34
35 #define pop_0() { pop_ptr->tag = TW_Empty; top++; }
36
37
38 static unsigned char type_table[32] = {
39 _PUSH_, _PUSH_, _PUSH_, _PUSH_,
40 _null_, _null_, _null_, _null_,
41 _REG0_, _REG0_, _REG0_, _REG0_,
42 _REG0_, _REG0_, _REG0_, _REG0_,
43 _NONE_, _null_, _NONE_, _PUSH_,
44 _NONE_, _PUSH_, _null_, _PUSH_,
45 _NONE_, _null_, _NONE_, _REG0_,
46 _NONE_, _REG0_, _NONE_, _REG0_
47 };
48
49 void load_store_instr(char type)
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*/
50 {
51 FPU_REG *pop_ptr; /* We need a version of FPU_st0_ptr which won't
52 change if the emulator is re-entered. */
53
54 pop_ptr = NULL; /* Initialized just to stop compiler warnings. */
55 switch ( type_table[(int) (unsigned) type] )
56 {
57 case _NONE_:
58 break;
59 case _REG0_:
60 pop_ptr = &st(0); /* Some of these instructions pop after
61 storing */
62
63 FPU_st0_ptr = pop_ptr; /* Set the global variables. */
64 FPU_st0_tag = FPU_st0_ptr->tag;
65 break;
66 case _PUSH_:
67 {
68 pop_ptr = &st(-1);
69 if ( pop_ptr->tag != TW_Empty )
70 { stack_overflow(); return; }
71 top--;
72 }
73 break;
74 case _null_:
75 Un_impl();
76 return;
77 #ifdef PARANOID
78 default:
79 EXCEPTION(EX_INTERNAL);
80 return;
81 #endif PARANOID
82 }
83
84 switch ( type )
85 {
86 case 000: /* fld m32real */
87 #ifdef PECULIAR_486
88 /* Default, this conveys no information, but an 80486 does it. */
89 clear_C1();
90 #endif PECULIAR_486
91 reg_load_single();
92 if ( (FPU_loaded_data.tag == TW_NaN) &&
93 real_2op_NaN(&FPU_loaded_data, &FPU_loaded_data, &FPU_loaded_data) )
94 {
95 top++;
96 break;
97 }
98 reg_move(&FPU_loaded_data, pop_ptr);
99 break;
100 case 001: /* fild m32int */
101 #ifdef PECULIAR_486
102 /* Default, this conveys no information, but an 80486 does it. */
103 clear_C1();
104 #endif PECULIAR_486
105 reg_load_int32();
106 reg_move(&FPU_loaded_data, pop_ptr);
107 break;
108 case 002: /* fld m64real */
109 #ifdef PECULIAR_486
110 /* Default, this conveys no information, but an 80486 does it. */
111 clear_C1();
112 #endif PECULIAR_486
113 reg_load_double();
114 if ( (FPU_loaded_data.tag == TW_NaN) &&
115 real_2op_NaN(&FPU_loaded_data, &FPU_loaded_data, &FPU_loaded_data) )
116 {
117 top++;
118 break;
119 }
120 reg_move(&FPU_loaded_data, pop_ptr);
121 break;
122 case 003: /* fild m16int */
123 #ifdef PECULIAR_486
124 /* Default, this conveys no information, but an 80486 does it. */
125 clear_C1();
126 #endif PECULIAR_486
127 reg_load_int16();
128 reg_move(&FPU_loaded_data, pop_ptr);
129 break;
130 case 010: /* fst m32real */
131 #ifdef PECULIAR_486
132 /* Default, this conveys no information, but an 80486 does it. */
133 clear_C1();
134 #endif PECULIAR_486
135 reg_store_single();
136 break;
137 case 011: /* fist m32int */
138 #ifdef PECULIAR_486
139 /* Default, this conveys no information, but an 80486 does it. */
140 clear_C1();
141 #endif PECULIAR_486
142 reg_store_int32();
143 break;
144 case 012: /* fst m64real */
145 #ifdef PECULIAR_486
146 /* Default, this conveys no information, but an 80486 does it. */
147 clear_C1();
148 #endif PECULIAR_486
149 reg_store_double();
150 break;
151 case 013: /* fist m16int */
152 #ifdef PECULIAR_486
153 /* Default, this conveys no information, but an 80486 does it. */
154 clear_C1();
155 #endif PECULIAR_486
156 reg_store_int16();
157 break;
158 case 014: /* fstp m32real */
159 #ifdef PECULIAR_486
160 /* Default, this conveys no information, but an 80486 does it. */
161 clear_C1();
162 #endif PECULIAR_486
163 if ( reg_store_single() )
164 pop_0(); /* pop only if the number was actually stored
165 (see the 80486 manual p16-28) */
166 break;
167 case 015: /* fistp m32int */
168 #ifdef PECULIAR_486
169 /* Default, this conveys no information, but an 80486 does it. */
170 clear_C1();
171 #endif PECULIAR_486
172 if ( reg_store_int32() )
173 pop_0(); /* pop only if the number was actually stored
174 (see the 80486 manual p16-28) */
175 break;
176 case 016: /* fstp m64real */
177 #ifdef PECULIAR_486
178 /* Default, this conveys no information, but an 80486 does it. */
179 clear_C1();
180 #endif PECULIAR_486
181 if ( reg_store_double() )
182 pop_0(); /* pop only if the number was actually stored
183 (see the 80486 manual p16-28) */
184 break;
185 case 017: /* fistp m16int */
186 #ifdef PECULIAR_486
187 /* Default, this conveys no information, but an 80486 does it. */
188 clear_C1();
189 #endif PECULIAR_486
190 if ( reg_store_int16() )
191 pop_0(); /* pop only if the number was actually stored
192 (see the 80486 manual p16-28) */
193 break;
194 case 020: /* fldenv m14/28byte */
195 fldenv();
196 break;
197 case 022: /* frstor m94/108byte */
198 frstor();
199 break;
200 case 023: /* fbld m80dec */
201 #ifdef PECULIAR_486
202 /* Default, this conveys no information, but an 80486 does it. */
203 clear_C1();
204 #endif PECULIAR_486
205 reg_load_bcd();
206 reg_move(&FPU_loaded_data, pop_ptr);
207 break;
208 case 024: /* fldcw */
209 RE_ENTRANT_CHECK_OFF;
210 control_word = get_fs_word((unsigned short *) FPU_data_address);
211 RE_ENTRANT_CHECK_ON;
212 if ( partial_status & ~control_word & CW_Exceptions )
213 partial_status |= (SW_Summary | SW_Backward);
214 else
215 partial_status &= ~(SW_Summary | SW_Backward);
216 #ifdef PECULIAR_486
217 control_word |= 0x40; /* An 80486 appears to always set this bit */
218 #endif PECULIAR_486
219 NO_NET_DATA_EFFECT;
220 NO_NET_INSTR_EFFECT;
221 break;
222 case 025: /* fld m80real */
223 #ifdef PECULIAR_486
224 /* Default, this conveys no information, but an 80486 does it. */
225 clear_C1();
226 #endif PECULIAR_486
227 reg_load_extended();
228 reg_move(&FPU_loaded_data, pop_ptr);
229 break;
230 case 027: /* fild m64int */
231 #ifdef PECULIAR_486
232 /* Default, this conveys no information, but an 80486 does it. */
233 clear_C1();
234 #endif PECULIAR_486
235 reg_load_int64();
236 reg_move(&FPU_loaded_data, pop_ptr);
237 break;
238 case 030: /* fstenv m14/28byte */
239 fstenv();
240 NO_NET_DATA_EFFECT;
241 break;
242 case 032: /* fsave */
243 fsave();
244 NO_NET_DATA_EFFECT;
245 break;
246 case 033: /* fbstp m80dec */
247 #ifdef PECULIAR_486
248 /* Default, this conveys no information, but an 80486 does it. */
249 clear_C1();
250 #endif PECULIAR_486
251 if ( reg_store_bcd() )
252 pop_0(); /* pop only if the number was actually stored
253 (see the 80486 manual p16-28) */
254 break;
255 case 034: /* fstcw m16int */
256 RE_ENTRANT_CHECK_OFF;
257 verify_area(VERIFY_WRITE,FPU_data_address,2);
258 put_fs_word(control_word, (short *) FPU_data_address);
259 RE_ENTRANT_CHECK_ON;
260 NO_NET_DATA_EFFECT;
261 NO_NET_INSTR_EFFECT;
262 break;
263 case 035: /* fstp m80real */
264 #ifdef PECULIAR_486
265 /* Default, this conveys no information, but an 80486 does it. */
266 clear_C1();
267 #endif PECULIAR_486
268 if ( reg_store_extended() )
269 pop_0(); /* pop only if the number was actually stored
270 (see the 80486 manual p16-28) */
271 break;
272 case 036: /* fstsw m2byte */
273 RE_ENTRANT_CHECK_OFF;
274 verify_area(VERIFY_WRITE,FPU_data_address,2);
275 put_fs_word(status_word(),(short *) FPU_data_address);
276 RE_ENTRANT_CHECK_ON;
277 NO_NET_DATA_EFFECT;
278 NO_NET_INSTR_EFFECT;
279 break;
280 case 037: /* fistp m64int */
281 #ifdef PECULIAR_486
282 /* Default, this conveys no information, but an 80486 does it. */
283 clear_C1();
284 #endif PECULIAR_486
285 if ( reg_store_int64() )
286 pop_0(); /* pop only if the number was actually stored
287 (see the 80486 manual p16-28) */
288 break;
289 }
290 }
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*/