Commit | Line | Data |
---|---|---|
cf76e892 JPM |
1 | // |
2 | // m68kdasm.c: 68000 instruction disassembly | |
3 | // | |
4 | // Originally part of the UAE 68000 cpu core | |
5 | // by Bernd Schmidt | |
6 | // | |
7 | // Adapted to Virtual Jaguar by James Hammons | |
8 | // | |
9 | // This file is distributed under the GNU Public License, version 3 or at your | |
10 | // option any later version. Read the file GPLv3 for details. | |
11 | // | |
12 | ||
13 | #include <string.h> | |
14 | #include "cpudefs.h" | |
15 | #include "cpuextra.h" | |
16 | #include "inlines.h" | |
17 | #include "readcpu.h" | |
18 | ||
19 | ||
20 | // Stuff from m68kinterface.c | |
21 | extern unsigned long IllegalOpcode(uint32_t opcode); | |
22 | extern cpuop_func * cpuFunctionTable[65536]; | |
23 | ||
24 | // Prototypes | |
25 | void HandleMovem(char * output, uint16_t data, int direction); | |
26 | ||
27 | // Local "global" variables | |
28 | static long int m68kpc_offset; | |
29 | ||
30 | #if 0 | |
31 | #define get_ibyte_1(o) get_byte(regs.pc + (regs.pc_p - regs.pc_oldp) + (o) + 1) | |
32 | #define get_iword_1(o) get_word(regs.pc + (regs.pc_p - regs.pc_oldp) + (o)) | |
33 | #define get_ilong_1(o) get_long(regs.pc + (regs.pc_p - regs.pc_oldp) + (o)) | |
34 | #else | |
35 | #define get_ibyte_1(o) m68k_read_memory_8(regs.pc + (o) + 1) | |
36 | #define get_iword_1(o) m68k_read_memory_16(regs.pc + (o)) | |
37 | #define get_ilong_1(o) m68k_read_memory_32(regs.pc + (o)) | |
38 | #endif | |
39 | ||
40 | ||
41 | //int32_t ShowEA(FILE * f, int reg, amodes mode, wordsizes size, char * buf) | |
42 | int32_t ShowEA(int mnemonic, int reg, amodes mode, wordsizes size, char * buf) | |
43 | { | |
44 | uint16_t dp; | |
45 | int8_t disp8; | |
46 | int16_t disp16; | |
47 | int r; | |
48 | uint32_t dispreg; | |
49 | uint32_t addr; | |
50 | int32_t offset = 0; | |
51 | char buffer[80]; | |
52 | ||
53 | switch (mode) | |
54 | { | |
55 | case Dreg: | |
56 | sprintf(buffer,"D%d", reg); | |
57 | break; | |
58 | case Areg: | |
59 | sprintf(buffer,"A%d", reg); | |
60 | break; | |
61 | case Aind: | |
62 | sprintf(buffer,"(A%d)", reg); | |
63 | break; | |
64 | case Aipi: | |
65 | sprintf(buffer,"(A%d)+", reg); | |
66 | break; | |
67 | case Apdi: | |
68 | sprintf(buffer,"-(A%d)", reg); | |
69 | break; | |
70 | case Ad16: | |
71 | disp16 = get_iword_1(m68kpc_offset); m68kpc_offset += 2; | |
72 | addr = m68k_areg(regs,reg) + (int16_t)disp16; | |
73 | sprintf(buffer,"(A%d,$%X) == $%lX", reg, disp16 & 0xFFFF, | |
74 | (unsigned long)addr); | |
75 | break; | |
76 | case Ad8r: | |
77 | dp = get_iword_1(m68kpc_offset); m68kpc_offset += 2; | |
78 | disp8 = dp & 0xFF; | |
79 | r = (dp & 0x7000) >> 12; | |
80 | dispreg = (dp & 0x8000 ? m68k_areg(regs,r) : m68k_dreg(regs,r)); | |
81 | ||
82 | if (!(dp & 0x800)) | |
83 | dispreg = (int32_t)(int16_t)(dispreg); | |
84 | ||
85 | dispreg <<= (dp >> 9) & 3; | |
86 | ||
87 | if (dp & 0x100) | |
88 | { | |
89 | int32_t outer = 0, disp = 0; | |
90 | int32_t base = m68k_areg(regs,reg); | |
91 | char name[10]; | |
92 | sprintf (name,"A%d, ",reg); | |
93 | if (dp & 0x80) { base = 0; name[0] = 0; } | |
94 | if (dp & 0x40) dispreg = 0; | |
95 | if ((dp & 0x30) == 0x20) { disp = (int32_t)(int16_t)get_iword_1(m68kpc_offset); m68kpc_offset += 2; } | |
96 | if ((dp & 0x30) == 0x30) { disp = get_ilong_1(m68kpc_offset); m68kpc_offset += 4; } | |
97 | base += disp; | |
98 | ||
99 | if ((dp & 0x3) == 0x2) { outer = (int32_t)(int16_t)get_iword_1(m68kpc_offset); m68kpc_offset += 2; } | |
100 | if ((dp & 0x3) == 0x3) { outer = get_ilong_1(m68kpc_offset); m68kpc_offset += 4; } | |
101 | ||
102 | if (!(dp & 4)) base += dispreg; | |
103 | if (dp & 3) base = m68k_read_memory_32(base); | |
104 | if (dp & 4) base += dispreg; | |
105 | ||
106 | addr = base + outer; | |
107 | sprintf(buffer,"(%s%c%d.%c*%d+%ld)+%ld == $%lX", name, | |
108 | dp & 0x8000 ? 'A' : 'D', (int)r, dp & 0x800 ? 'L' : 'W', | |
109 | 1 << ((dp >> 9) & 3), | |
110 | (long)disp, (long)outer, (unsigned long)addr); | |
111 | } | |
112 | else | |
113 | { | |
114 | addr = m68k_areg(regs,reg) + (int32_t)((int8_t)disp8) + dispreg; | |
115 | sprintf (buffer,"(A%d, %c%d.%c*%d, $%X) == $%lX", reg, | |
116 | dp & 0x8000 ? 'A' : 'D', (int)r, dp & 0x800 ? 'L' : 'W', | |
117 | 1 << ((dp >> 9) & 3), disp8, (unsigned long)addr); | |
118 | } | |
119 | break; | |
120 | case PC16: | |
121 | addr = m68k_getpc() + m68kpc_offset; | |
122 | disp16 = get_iword_1(m68kpc_offset); m68kpc_offset += 2; | |
123 | addr += (int16_t)disp16; | |
124 | sprintf(buffer,"(PC, $%X) == $%lX", disp16 & 0xFFFF, (unsigned long)addr); | |
125 | break; | |
126 | case PC8r: | |
127 | addr = m68k_getpc() + m68kpc_offset; | |
128 | dp = get_iword_1(m68kpc_offset); m68kpc_offset += 2; | |
129 | disp8 = dp & 0xFF; | |
130 | r = (dp & 0x7000) >> 12; | |
131 | dispreg = dp & 0x8000 ? m68k_areg(regs,r) : m68k_dreg(regs,r); | |
132 | ||
133 | if (!(dp & 0x800)) | |
134 | dispreg = (int32_t)(int16_t)(dispreg); | |
135 | ||
136 | dispreg <<= (dp >> 9) & 3; | |
137 | ||
138 | if (dp & 0x100) | |
139 | { | |
140 | int32_t outer = 0,disp = 0; | |
141 | int32_t base = addr; | |
142 | char name[10]; | |
143 | sprintf (name,"PC, "); | |
144 | if (dp & 0x80) { base = 0; name[0] = 0; } | |
145 | if (dp & 0x40) dispreg = 0; | |
146 | if ((dp & 0x30) == 0x20) { disp = (int32_t)(int16_t)get_iword_1(m68kpc_offset); m68kpc_offset += 2; } | |
147 | if ((dp & 0x30) == 0x30) { disp = get_ilong_1(m68kpc_offset); m68kpc_offset += 4; } | |
148 | base += disp; | |
149 | ||
150 | if ((dp & 0x3) == 0x2) | |
151 | { | |
152 | outer = (int32_t)(int16_t)get_iword_1(m68kpc_offset); | |
153 | m68kpc_offset += 2; | |
154 | } | |
155 | ||
156 | if ((dp & 0x3) == 0x3) | |
157 | { | |
158 | outer = get_ilong_1(m68kpc_offset); | |
159 | m68kpc_offset += 4; | |
160 | } | |
161 | ||
162 | if (!(dp & 4)) base += dispreg; | |
163 | if (dp & 3) base = m68k_read_memory_32(base); | |
164 | if (dp & 4) base += dispreg; | |
165 | ||
166 | addr = base + outer; | |
167 | sprintf(buffer,"(%s%c%d.%c*%d+%ld)+%ld == $%lX", name, | |
168 | dp & 0x8000 ? 'A' : 'D', (int)r, dp & 0x800 ? 'L' : 'W', | |
169 | 1 << ((dp >> 9) & 3), (long)disp, (long)outer, (unsigned long)addr); | |
170 | } | |
171 | else | |
172 | { | |
173 | addr += (int32_t)((int8_t)disp8) + dispreg; | |
174 | sprintf(buffer,"(PC, %c%d.%c*%d, $%X) == $%lX", dp & 0x8000 ? 'A' : 'D', | |
175 | (int)r, dp & 0x800 ? 'L' : 'W', 1 << ((dp >> 9) & 3), | |
176 | disp8, (unsigned long)addr); | |
177 | } | |
178 | break; | |
179 | case absw: | |
180 | sprintf(buffer,"$%lX", (unsigned long)(int32_t)(int16_t)get_iword_1(m68kpc_offset)); | |
181 | m68kpc_offset += 2; | |
182 | break; | |
183 | case absl: | |
184 | sprintf(buffer,"$%lX", (unsigned long)get_ilong_1(m68kpc_offset)); | |
185 | m68kpc_offset += 4; | |
186 | break; | |
187 | case imm: | |
188 | switch (size) | |
189 | { | |
190 | case sz_byte: | |
191 | sprintf(buffer,"#$%X", (unsigned int)(get_iword_1(m68kpc_offset) & 0xFF)); | |
192 | m68kpc_offset += 2; | |
193 | break; | |
194 | case sz_word: | |
195 | sprintf(buffer,"#$%X", (unsigned int)(get_iword_1(m68kpc_offset) & 0xFFFF)); | |
196 | m68kpc_offset += 2; | |
197 | break; | |
198 | case sz_long: | |
199 | sprintf(buffer,"#$%lX", (unsigned long)(get_ilong_1(m68kpc_offset))); | |
200 | m68kpc_offset += 4; | |
201 | break; | |
202 | default: | |
203 | break; | |
204 | } | |
205 | break; | |
206 | case imm0: | |
207 | offset = (int32_t)(int8_t)get_iword_1(m68kpc_offset); | |
208 | m68kpc_offset += 2; | |
209 | sprintf(buffer,"#$%X", (unsigned int)(offset & 0xFF)); | |
210 | break; | |
211 | case imm1: | |
212 | offset = (int32_t)(int16_t)get_iword_1(m68kpc_offset); | |
213 | m68kpc_offset += 2; | |
214 | ||
215 | if (mnemonic == i_MVMEL) | |
216 | HandleMovem(buffer, offset, 0); | |
217 | else if (mnemonic == i_MVMLE) | |
218 | HandleMovem(buffer, offset, 1); | |
219 | else | |
220 | sprintf(buffer,"#$%X", (unsigned int)(offset & 0xFFFF)); | |
221 | ||
222 | break; | |
223 | case imm2: | |
224 | offset = (int32_t)get_ilong_1(m68kpc_offset); | |
225 | m68kpc_offset += 4; | |
226 | sprintf(buffer,"#$%lX", (unsigned long)(offset & 0xFFFFFFFF)); | |
227 | break; | |
228 | case immi: | |
229 | offset = (int32_t)(int8_t)(reg & 0xFF); | |
230 | sprintf(buffer,"#$%lX", (unsigned long)(offset & 0xFFFFFFFF)); | |
231 | break; | |
232 | default: | |
233 | break; | |
234 | } | |
235 | ||
236 | // if (buf == 0) | |
237 | // fprintf(f, "%s", buffer); | |
238 | // else | |
239 | strcat(buf, buffer); | |
240 | ||
241 | return offset; | |
242 | } | |
243 | ||
244 | ||
245 | void HandleMovem(char * output, uint16_t data, int direction) | |
246 | { | |
247 | uint16_t ascending[16] = { | |
248 | 0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080, | |
249 | 0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000, 0x8000 }; | |
250 | uint16_t descending[16] = { | |
251 | 0x8000, 0x4000, 0x2000, 0x1000, 0x0800, 0x0400, 0x0200, 0x0100, | |
252 | 0x0080, 0x0040, 0x0020, 0x0010, 0x0008, 0x0004, 0x0002, 0x0001 }; | |
253 | ||
254 | int i, j, first, runLength, firstPrint = 1; | |
255 | char buf[16]; | |
256 | uint16_t * bitMask; | |
257 | ||
258 | bitMask = (direction ? descending : ascending); | |
259 | output[0] = 0; | |
260 | ||
261 | // Handle D0-D7... | |
262 | for(i=0; i<8; i++) | |
263 | { | |
264 | if (data & bitMask[i]) | |
265 | { | |
266 | first = i; | |
267 | runLength = 0; | |
268 | ||
269 | for(j=i+1; j<8 && (data & bitMask[j]); j++) | |
270 | runLength++; | |
271 | ||
272 | i += runLength; | |
273 | ||
274 | if (firstPrint) | |
275 | firstPrint = 0; | |
276 | else | |
277 | strcat(output, "/"); | |
278 | ||
279 | sprintf(buf, "D%d", first); | |
280 | strcat(output, buf); | |
281 | ||
282 | if (runLength > 0) | |
283 | { | |
284 | sprintf(buf, "-D%d", first + runLength); | |
285 | strcat(output, buf); | |
286 | } | |
287 | } | |
288 | } | |
289 | ||
290 | // Handle A0-A7... | |
291 | for(i=0; i<8; i++) | |
292 | { | |
293 | if (data & bitMask[i + 8]) | |
294 | { | |
295 | first = i; | |
296 | runLength = 0; | |
297 | ||
298 | for(j=i+1; j<8 && (data & bitMask[j+8]); j++) | |
299 | runLength++; | |
300 | ||
301 | i += runLength; | |
302 | ||
303 | if (firstPrint) | |
304 | firstPrint = 0; | |
305 | else | |
306 | strcat(output, "/"); | |
307 | ||
308 | sprintf(buf, "A%d", first); | |
309 | strcat(output, buf); | |
310 | ||
311 | if (runLength > 0) | |
312 | { | |
313 | sprintf(buf, "-A%d", first + runLength); | |
314 | strcat(output, buf); | |
315 | } | |
316 | } | |
317 | } | |
318 | } | |
319 | ||
320 | ||
321 | unsigned int M68KDisassemble(char * output, uint32_t addr, unsigned int OpCodes) | |
322 | { | |
323 | char f[256], str[256]; | |
324 | char src[256], dst[256]; | |
325 | static const char * const ccnames[] = | |
326 | { "RA","RN","HI","LS","CC","CS","NE","EQ", | |
327 | "VC","VS","PL","MI","GE","LT","GT","LE" }; | |
328 | ||
329 | str[0] = 0; | |
330 | output[0] = 0; | |
331 | uint32_t newpc = 0; | |
332 | m68kpc_offset = addr - m68k_getpc(); | |
333 | long int pcOffsetSave = m68kpc_offset; | |
334 | int opwords; | |
335 | char instrname[20]; | |
336 | const struct mnemolookup * lookup; | |
337 | ||
338 | uint32_t opcode = get_iword_1(m68kpc_offset); | |
339 | m68kpc_offset += 2; | |
340 | ||
341 | if (cpuFunctionTable[opcode] == IllegalOpcode) | |
342 | opcode = 0x4AFC; | |
343 | ||
344 | struct instr * dp = table68k + opcode; | |
345 | ||
346 | for(lookup=lookuptab; lookup->mnemo!=dp->mnemo; lookup++) | |
347 | ; | |
348 | ||
349 | strcpy(instrname, lookup->name); | |
350 | char * ccpt = strstr(instrname, "cc"); | |
351 | ||
352 | if (ccpt) | |
353 | strncpy(ccpt, ccnames[dp->cc], 2); | |
354 | ||
355 | sprintf(f, "%s", instrname); | |
356 | strcat(str, f); | |
357 | ||
358 | switch (dp->size) | |
359 | { | |
360 | case sz_byte: strcat(str, ".B\t"); break; | |
361 | case sz_word: strcat(str, ".W\t"); break; | |
362 | case sz_long: strcat(str, ".L\t"); break; | |
363 | default: strcat(str, "\t"); break; | |
364 | } | |
365 | ||
366 | // Get source and destination operands (if any) | |
367 | src[0] = dst[0] = f[0] = 0; | |
368 | ||
369 | if (dp->suse) | |
370 | newpc = m68k_getpc() + m68kpc_offset | |
371 | + ShowEA(dp->mnemo, dp->sreg, dp->smode, dp->size, src); | |
372 | ||
373 | if (dp->duse) | |
374 | newpc = m68k_getpc() + m68kpc_offset | |
375 | + ShowEA(dp->mnemo, dp->dreg, dp->dmode, dp->size, dst); | |
376 | ||
377 | // Handle execptions to the standard rules | |
378 | if (dp->mnemo == i_BSR || dp->mnemo == i_Bcc) | |
379 | sprintf(f, "$%lX", (long)newpc); | |
380 | else if (dp->mnemo == i_DBcc) | |
381 | sprintf(f, "%s, $%lX", src, (long)newpc); | |
382 | else if (dp->mnemo == i_MVMEL) | |
383 | sprintf(f, "%s, %s", dst, src); | |
384 | else | |
385 | sprintf(f, "%s%s%s", src, (dp->suse && dp->duse ? ", " : ""), dst); | |
386 | ||
387 | strcat(str, f); | |
388 | ||
389 | if (ccpt) | |
390 | { | |
391 | sprintf(f, " (%s)", (cctrue(dp->cc) ? "true" : "false")); | |
392 | strcat(str, f); | |
393 | } | |
394 | ||
395 | // Add byte(s) display to front of disassembly | |
396 | long int numberOfBytes = m68kpc_offset - pcOffsetSave; | |
397 | ||
398 | for(opwords=0; opwords<5; opwords++) | |
399 | { | |
400 | if (((opwords + 1) * 2) <= numberOfBytes) | |
401 | sprintf(f, "%04X ", get_iword_1(pcOffsetSave + opwords * 2)); | |
402 | else | |
403 | sprintf(f, " "); | |
404 | ||
405 | strcat(output, f); | |
406 | } | |
407 | ||
408 | if (OpCodes) | |
409 | { | |
410 | strcat(output, str); | |
411 | } | |
412 | else | |
413 | { | |
414 | strcpy(output, str); | |
415 | } | |
416 | ||
417 | return numberOfBytes; | |
418 | } | |
419 | ||
420 | ||
421 | // | |
422 | // Disassemble one instruction at pc and store in str_buff | |
423 | // | |
424 | unsigned int m68k_disassemble(char * str_buff, unsigned int pc, unsigned int cpu_type, unsigned int OpCodes) | |
425 | { | |
426 | return M68KDisassemble(str_buff, pc, OpCodes); | |
427 | } | |
428 |