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32x: built-in BIOS; reset handling; 68k memhandler split
[picodrive.git] / cpu / Cyclone / OpArith.cpp
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CommitLineData
1\r
2#include "app.h"\r
3\r
4// --------------------- Opcodes 0x0000+ ---------------------\r
5// Emit an Ori/And/Sub/Add/Eor/Cmp Immediate opcode, 0000ttt0 ssaaaaaa\r
6int OpArith(int op)\r
7{\r
8 int type=0,size=0;\r
9 int sea=0,tea=0;\r
10 int use=0;\r
11 const char *shiftstr="";\r
12\r
13 // Get source and target EA\r
14 type=(op>>9)&7; if (type==4 || type>=7) return 1;\r
15 size=(op>>6)&3; if (size>=3) return 1;\r
16 sea= 0x003c;\r
17 tea=op&0x003f;\r
18\r
19 // See if we can do this opcode:\r
20 if (EaCanRead(tea,size)==0) return 1;\r
21 if (EaCanWrite(tea)==0 || EaAn(tea)) return 1;\r
22\r
23 use=OpBase(op,size);\r
24 if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r
25\r
26 OpStart(op, sea, tea); Cycles=4;\r
27\r
28 // imm must be read first\r
29 EaCalcReadNoSE(-1,10,sea,size,0);\r
30 EaCalcReadNoSE((type!=6)?11:-1,0,tea,size,0x003f);\r
31\r
32 if (size<2) shiftstr=(char *)(size?",asl #16":",asl #24");\r
33 if (size<2) ot(" mov r10,r10,asl #%i\n",size?16:24);\r
34\r
35 ot(";@ Do arithmetic:\n");\r
36\r
37 if (type==0) ot(" orr r1,r10,r0%s\n",shiftstr);\r
38 if (type==1) ot(" and r1,r10,r0%s\n",shiftstr);\r
39 if (type==2||type==6)\r
40 ot(" rsbs r1,r10,r0%s ;@ Defines NZCV\n",shiftstr);\r
41 if (type==3) ot(" adds r1,r10,r0%s ;@ Defines NZCV\n",shiftstr);\r
42 if (type==5) ot(" eor r1,r10,r0%s\n",shiftstr);\r
43\r
44 if (type<2 || type==5) ot(" adds r1,r1,#0 ;@ Defines NZ, clears CV\n"); // 0,1,5\r
45\r
46 if (type< 2) OpGetFlags(0,0); // Ori/And\r
47 if (type==2) OpGetFlags(1,1); // Sub: Subtract/X-bit\r
48 if (type==3) OpGetFlags(0,1); // Add: X-bit\r
49 if (type==5) OpGetFlags(0,0); // Eor\r
50 if (type==6) OpGetFlags(1,0); // Cmp: Subtract\r
51 ot("\n");\r
52\r
53 if (type!=6)\r
54 {\r
55 EaWrite(11, 1, tea,size,0x003f,1);\r
56 }\r
57\r
58 // Correct cycles:\r
59 if (type==6)\r
60 {\r
61 if (size>=2 && tea<0x10) Cycles+=2;\r
62 }\r
63 else\r
64 {\r
65 if (size>=2) Cycles+=4;\r
66 if (tea>=8) Cycles+=4;\r
67 if (type==1 && size>=2 && tea<8) Cycles-=2;\r
68 }\r
69\r
70 OpEnd(sea,tea);\r
71\r
72 return 0;\r
73}\r
74\r
75// --------------------- Opcodes 0x5000+ ---------------------\r
76int OpAddq(int op)\r
77{\r
78 // 0101nnnt xxeeeeee (nnn=#8,1-7 t=addq/subq xx=size, eeeeee=EA)\r
79 int num=0,type=0,size=0,ea=0;\r
80 int use=0;\r
81 char count[16]="";\r
82 int shift=0;\r
83\r
84 num =(op>>9)&7; if (num==0) num=8;\r
85 type=(op>>8)&1;\r
86 size=(op>>6)&3; if (size>=3) return 1;\r
87 ea = op&0x3f;\r
88\r
89 // See if we can do this opcode:\r
90 if (EaCanRead (ea,size)==0) return 1;\r
91 if (EaCanWrite(ea) ==0) return 1;\r
92 if (size == 0 && EaAn(ea) ) return 1;\r
93\r
94 use=OpBase(op,size,1);\r
95\r
96 if (num!=8) use|=0x0e00; // If num is not 8, use same handler\r
97 if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r
98\r
99 OpStart(op,ea);\r
100 Cycles=ea<8?4:8;\r
101 if(type==0&&size==1) Cycles=ea<0x10?4:8;\r
102 if(size>=2) Cycles=ea<0x10?8:12;\r
103\r
104 if (size>0 && (ea&0x38)==0x08) size=2; // addq.w #n,An is also 32-bit\r
105\r
106 EaCalcReadNoSE(11,0,ea,size,0x003f);\r
107\r
108 shift=32-(8<<size);\r
109\r
110 if (num!=8)\r
111 {\r
112 int lsr=9-shift;\r
113\r
114 ot(" and r2,r8,#0x0e00 ;@ Get quick value\n");\r
115\r
116 if (lsr>=0) sprintf(count,"r2,lsr #%d", lsr);\r
117 else sprintf(count,"r2,lsl #%d", -lsr);\r
118\r
119 ot("\n");\r
120 }\r
121 else\r
122 {\r
123 sprintf(count,"#0x%.4x",8<<shift);\r
124 }\r
125\r
126 if (size<2) ot(" mov r0,r0,asl #%d\n\n",size?16:24);\r
127\r
128 if (type==0) ot(" adds r1,r0,%s\n",count);\r
129 if (type==1) ot(" subs r1,r0,%s\n",count);\r
130\r
131 if ((ea&0x38)!=0x08) OpGetFlags(type,1);\r
132 ot("\n");\r
133\r
134 EaWrite(11, 1, ea,size,0x003f,1);\r
135\r
136 OpEnd(ea);\r
137\r
138 return 0;\r
139}\r
140\r
141// --------------------- Opcodes 0x8000+ ---------------------\r
142// 1t0tnnnd xxeeeeee (tt=type:or/sub/and/add xx=size, eeeeee=EA)\r
143int OpArithReg(int op)\r
144{\r
145 int use=0;\r
146 int type=0,size=0,dir=0,rea=0,ea=0;\r
147 const char *asl="";\r
148 const char *strop=0;\r
149\r
150 type=(op>>12)&5;\r
151 rea =(op>> 9)&7;\r
152 dir =(op>> 8)&1; // er,re\r
153 size=(op>> 6)&3; if (size>=3) return 1;\r
154 ea = op&0x3f;\r
155\r
156 if (dir && ea<0x10) return 1; // addx/subx opcode\r
157\r
158 // See if we can do this opcode:\r
159 if (dir==0 && EaCanRead (ea,size)==0) return 1;\r
160 if (dir && EaCanWrite(ea)==0) return 1;\r
161 if ((size==0||!(type&1))&&EaAn(ea)) return 1;\r
162\r
163 use=OpBase(op,size);\r
164 use&=~0x0e00; // Use same opcode for Dn\r
165 if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r
166\r
167 OpStart(op,ea); Cycles=4;\r
168\r
169 EaCalcReadNoSE(dir?11:-1,0,ea,size,0x003f);\r
170\r
171 EaCalcReadNoSE(dir?-1:11,1,rea,size,0x0e00);\r
172\r
173 ot(";@ Do arithmetic:\n");\r
174 if (type==0) strop = "orr";\r
175 if (type==1) strop = (char *) (dir ? "subs" : "rsbs");\r
176 if (type==4) strop = "and";\r
177 if (type==5) strop = "adds";\r
178\r
179 if (size==0) asl=",asl #24";\r
180 if (size==1) asl=",asl #16";\r
181\r
182 if (size<2) ot(" mov r0,r0%s\n",asl);\r
183 ot(" %s r1,r0,r1%s\n",strop,asl);\r
184\r
185 if ((type&1)==0) ot(" adds r1,r1,#0 ;@ Defines NZ, clears CV\n");\r
186\r
187 OpGetFlags(type==1,type&1); // 1==subtract\r
188 ot("\n");\r
189\r
190 ot(";@ Save result:\n");\r
191 if (size<2) ot(" mov r1,r1,asr #%d\n",size?16:24);\r
192 if (dir) EaWrite(11, 1, ea,size,0x003f,0,0);\r
193 else EaWrite(11, 1,rea,size,0x0e00,0,0);\r
194\r
195 if(rea==ea) {\r
196 if(ea<8) Cycles=(size>=2)?8:4; else Cycles+=(size>=2)?26:14;\r
197 } else if(dir) {\r
198 Cycles+=4;\r
199 if(size>=2) Cycles+=4;\r
200 } else {\r
201 if(size>=2) {\r
202 Cycles+=2;\r
203 if(ea<0x10||ea==0x3c) Cycles+=2;\r
204 }\r
205 }\r
206\r
207 OpEnd(ea);\r
208\r
209 return 0;\r
210}\r
211\r
212// --------------------- Opcodes 0x80c0+ ---------------------\r
213int OpMul(int op)\r
214{\r
215 // Div/Mul: 1m00nnns 11eeeeee (m=Mul, nnn=Register Dn, s=signed, eeeeee=EA)\r
216 int type=0,rea=0,sign=0,ea=0;\r
217 int use=0;\r
218\r
219 type=(op>>14)&1; // div/mul\r
220 rea =(op>> 9)&7;\r
221 sign=(op>> 8)&1;\r
222 ea = op&0x3f;\r
223\r
224 // See if we can do this opcode:\r
225 if (EaCanRead(ea,1)==0||EaAn(ea)) return 1;\r
226\r
227 use=OpBase(op,1);\r
228 use&=~0x0e00; // Use same for all registers\r
229 if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r
230\r
231 OpStart(op,ea);\r
232 if(type) Cycles=54;\r
233 else Cycles=sign?158:140;\r
234\r
235 EaCalcReadNoSE(-1,0,ea,1,0x003f);\r
236\r
237 EaCalc(11,0x0e00,rea, 2);\r
238 EaRead(11, 2,rea, 2,0x0e00);\r
239\r
240 ot(" movs r1,r0,asl #16\n");\r
241\r
242 if (type==0) // div\r
243 {\r
244 // the manual says C is always cleared, but neither Musashi nor FAME do that\r
245 //ot(" bic r10,r10,#0x20000000 ;@ always clear C\n");\r
246 ot(" beq divzero%.4x ;@ division by zero\n",op);\r
247 ot("\n");\r
248 \r
249 if (sign)\r
250 {\r
251 ot(" mov r12,#0 ;@ r12 = 1 or 2 if the result is negative\n");\r
252 ot(" tst r2,r2\n");\r
253 ot(" orrmi r12,r12,#2\n");\r
254 ot(" rsbmi r2,r2,#0 ;@ Make r2 positive\n");\r
255 ot("\n");\r
256 ot(" movs r0,r1,asr #16\n");\r
257 ot(" orrmi r12,r12,#1\n");\r
258 ot(" rsbmi r0,r0,#0 ;@ Make r0 positive\n");\r
259 ot("\n");\r
260 ot(";@ detect the nasty 0x80000000 / -1 situation\n");\r
261 ot(" mov r3,r2,asr #31\n");\r
262 ot(" eors r3,r3,r1,asr #16\n");\r
263 ot(" beq wrendofop%.4x\n",op);\r
264 }\r
265 else\r
266 {\r
267 ot(" mov r0,r1,lsr #16 ;@ use only 16 bits of divisor\n");\r
268 }\r
269\r
270 ot("\n");\r
271 ot(";@ Divide r2 by r0\n");\r
272 ot(" mov r3,#0\n");\r
273 ot(" mov r1,r0\n");\r
274 ot("\n");\r
275 ot(";@ Shift up divisor till it's just less than numerator\n");\r
276 ot("Shift%.4x%s\n",op,ms?"":":");\r
277 ot(" cmp r1,r2,lsr #1\n");\r
278 ot(" movls r1,r1,lsl #1\n");\r
279 ot(" bcc Shift%.4x\n",op);\r
280 ot("\n");\r
281\r
282 ot("Divide%.4x%s\n",op,ms?"":":");\r
283 ot(" cmp r2,r1\n");\r
284 ot(" adc r3,r3,r3 ;@ Double r3 and add 1 if carry set\n");\r
285 ot(" subcs r2,r2,r1\n");\r
286 ot(" teq r1,r0\n");\r
287 ot(" movne r1,r1,lsr #1\n");\r
288 ot(" bne Divide%.4x\n",op);\r
289 ot("\n");\r
290 ot(";@r3==quotient,r2==remainder\n");\r
291\r
292 if (sign)\r
293 {\r
294 // sign correction\r
295 ot(" and r1,r12,#1\n");\r
296 ot(" teq r1,r12,lsr #1\n");\r
297 ot(" rsbne r3,r3,#0 ;@ negate if quotient is negative\n");\r
298 ot(" tst r12,#2\n");\r
299 ot(" rsbne r2,r2,#0 ;@ negate the remainder if divident was negative\n");\r
300 ot("\n");\r
301\r
302 // signed overflow check\r
303 ot(" mov r1,r3,asl #16\n");\r
304 ot(" cmp r3,r1,asr #16 ;@ signed overflow?\n");\r
305 ot(" orrne r10,r10,#0x10000000 ;@ set overflow flag\n");\r
306 ot(" bne endofop%.4x ;@ overflow!\n",op);\r
307 ot("\n");\r
308 ot("wrendofop%.4x%s\n",op,ms?"":":");\r
309 }\r
310 else\r
311 {\r
312 // overflow check\r
313 ot(" movs r1,r3,lsr #16 ;@ check for overflow condition\n");\r
314 ot(" orrne r10,r10,#0x10000000 ;@ set overflow flag\n");\r
315 ot(" bne endofop%.4x ;@ overflow!\n",op);\r
316 ot("\n");\r
317 }\r
318\r
319 ot(" mov r1,r3,lsl #16 ;@ Clip to 16-bits\n");\r
320 ot(" adds r1,r1,#0 ;@ Defines NZ, clears CV\n");\r
321 OpGetFlags(0,0);\r
322\r
323 ot(" mov r1,r1,lsr #16\n");\r
324 ot(" orr r1,r1,r2,lsl #16 ;@ Insert remainder\n");\r
325 }\r
326\r
327 if (type==1)\r
328 {\r
329 ot(";@ Get 16-bit signs right:\n");\r
330 ot(" mov r0,r1,%s #16\n",sign?"asr":"lsr");\r
331 ot(" mov r2,r2,lsl #16\n");\r
332 ot(" mov r2,r2,%s #16\n",sign?"asr":"lsr");\r
333 ot("\n");\r
334\r
335 ot(" mul r1,r2,r0\n");\r
336 ot(" adds r1,r1,#0 ;@ Defines NZ, clears CV\n");\r
337 OpGetFlags(0,0);\r
338 }\r
339 ot("\n");\r
340\r
341 EaWrite(11, 1,rea, 2,0x0e00,1);\r
342\r
343 if (type==0) ot("endofop%.4x%s\n",op,ms?"":":");\r
344 OpEnd(ea);\r
345\r
346 if (type==0) // div\r
347 {\r
348 ot("divzero%.4x%s\n",op,ms?"":":");\r
349 ot(" mov r0,#5 ;@ Divide by zero\n");\r
350 ot(" bl Exception\n");\r
351 Cycles+=38;\r
352 OpEnd(ea);\r
353 ot("\n");\r
354 }\r
355\r
356 return 0;\r
357}\r
358\r
359// Get X Bit into carry - trashes r2\r
360int GetXBit(int subtract)\r
361{\r
362 ot(";@ Get X bit:\n");\r
363 ot(" ldr r2,[r7,#0x4c]\n");\r
364 if (subtract) ot(" mvn r2,r2 ;@ Invert it\n");\r
365 ot(" msr cpsr_flg,r2 ;@ Get into Carry\n");\r
366 ot("\n");\r
367 return 0;\r
368}\r
369\r
370// --------------------- Opcodes 0x8100+ ---------------------\r
371// 1t00ddd1 0000asss - sbcd/abcd Ds,Dd or -(As),-(Ad)\r
372int OpAbcd(int op)\r
373{\r
374 int use=0;\r
375 int type=0,sea=0,mem=0,dea=0;\r
376 \r
377 type=(op>>14)&1; // sbcd/abcd\r
378 dea =(op>> 9)&7;\r
379 mem =(op>> 3)&1;\r
380 sea = op &7;\r
381\r
382 if (mem) { sea|=0x20; dea|=0x20; }\r
383\r
384 use=op&~0x0e07; // Use same opcode for all registers..\r
385 if (sea==0x27) use|=0x0007; // ___x.b -(a7)\r
386 if (dea==0x27) use|=0x0e00; // ___x.b -(a7)\r
387 if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r
388\r
389 OpStart(op,sea,dea); Cycles=6;\r
390\r
391 if (mem)\r
392 {\r
393 ot(";@ Get src/dest EA vals\n");\r
394 EaCalc (0,0x000f, sea,0,1);\r
395 EaRead (0, 6, sea,0,0x000f,1);\r
396 EaCalcReadNoSE(11,0,dea,0,0x0e00);\r
397 }\r
398 else\r
399 {\r
400 ot(";@ Get src/dest reg vals\n");\r
401 EaCalcReadNoSE(-1,6,sea,0,0x0007);\r
402 EaCalcReadNoSE(11,0,dea,0,0x0e00);\r
403 ot(" mov r6,r6,asl #24\n");\r
404 }\r
405 ot(" mov r1,r0,asl #24\n\n");\r
406\r
407 ot(" bic r10,r10,#0xb1000000 ;@ clear all flags except old Z\n");\r
408\r
409 if (type)\r
410 {\r
411 ot(" ldr r0,[r7,#0x4c] ;@ Get X bit\n");\r
412 ot(" mov r3,#0x00f00000\n");\r
413 ot(" and r2,r3,r1,lsr #4\n");\r
414 ot(" tst r0,#0x20000000\n");\r
415 ot(" and r0,r3,r6,lsr #4\n");\r
416 ot(" add r0,r0,r2\n");\r
417 ot(" addne r0,r0,#0x00100000\n");\r
418// ot(" tst r0,#0x00800000\n");\r
419// ot(" orreq r10,r10,#0x01000000 ;@ Undefined V behavior\n");\r
420 ot(" cmp r0,#0x00900000\n");\r
421 ot(" addhi r0,r0,#0x00600000 ;@ Decimal adjust units\n");\r
422\r
423 ot(" mov r2,r1,lsr #28\n");\r
424 ot(" add r0,r0,r2,lsl #24\n");\r
425 ot(" mov r2,r6,lsr #28\n");\r
426 ot(" add r0,r0,r2,lsl #24\n");\r
427 ot(" cmp r0,#0x09900000\n");\r
428 ot(" orrhi r10,r10,#0x20000000 ;@ C\n");\r
429 ot(" subhi r0,r0,#0x0a000000\n");\r
430// ot(" and r3,r10,r0,lsr #3 ;@ Undefined V behavior part II\n");\r
431// ot(" orr r10,r10,r3,lsl #4 ;@ V\n");\r
432 ot(" movs r0,r0,lsl #4\n");\r
433 ot(" orrmi r10,r10,#0x90000000 ;@ Undefined N+V behavior\n"); // this is what Musashi really does\r
434 ot(" bicne r10,r10,#0x40000000 ;@ Z flag\n");\r
435 }\r
436 else\r
437 {\r
438 ot(" ldr r0,[r7,#0x4c] ;@ Get X bit\n");\r
439 ot(" mov r3,#0x00f00000\n");\r
440 ot(" and r2,r3,r6,lsr #4\n");\r
441 ot(" tst r0,#0x20000000\n");\r
442 ot(" and r0,r3,r1,lsr #4\n");\r
443 ot(" sub r0,r0,r2\n");\r
444 ot(" subne r0,r0,#0x00100000\n");\r
445// ot(" tst r0,#0x00800000\n");\r
446// ot(" orreq r10,r10,#0x01000000 ;@ Undefined V behavior\n");\r
447 ot(" cmp r0,#0x00900000\n");\r
448 ot(" subhi r0,r0,#0x00600000 ;@ Decimal adjust units\n");\r
449\r
450 ot(" mov r2,r1,lsr #28\n");\r
451 ot(" add r0,r0,r2,lsl #24\n");\r
452 ot(" mov r2,r6,lsr #28\n");\r
453 ot(" sub r0,r0,r2,lsl #24\n");\r
454 ot(" cmp r0,#0x09900000\n");\r
455 ot(" orrhi r10,r10,#0xa0000000 ;@ N and C\n");\r
456 ot(" addhi r0,r0,#0x0a000000\n");\r
457// ot(" and r3,r10,r0,lsr #3 ;@ Undefined V behavior part II\n");\r
458// ot(" orr r10,r10,r3,lsl #4 ;@ V\n");\r
459 ot(" movs r0,r0,lsl #4\n");\r
460// ot(" orrmi r10,r10,#0x80000000 ;@ Undefined N behavior\n");\r
461 ot(" bicne r10,r10,#0x40000000 ;@ Z flag\n");\r
462 }\r
463\r
464 ot(" str r10,[r7,#0x4c] ;@ Save X bit\n");\r
465 ot("\n");\r
466\r
467 EaWrite(11, 0, dea,0,0x0e00,1);\r
468\r
469 ot(" ldr r6,[r7,#0x54]\n");\r
470 OpEnd(sea,dea);\r
471\r
472 return 0;\r
473}\r
474\r
475// 01001000 00eeeeee - nbcd <ea>\r
476int OpNbcd(int op)\r
477{\r
478 int use=0;\r
479 int ea=0;\r
480 \r
481 ea=op&0x3f;\r
482\r
483 if(EaCanWrite(ea)==0||EaAn(ea)) return 1;\r
484\r
485 use=OpBase(op,0);\r
486 if(op!=use) { OpUse(op,use); return 0; } // Use existing handler\r
487\r
488 OpStart(op,ea); Cycles=6;\r
489 if(ea >= 8) Cycles+=2;\r
490\r
491 EaCalcReadNoSE(6,0,ea,0,0x003f);\r
492\r
493 // this is rewrite of Musashi's code\r
494 ot(" ldr r2,[r7,#0x4c]\n");\r
495 ot(" bic r10,r10,#0xb0000000 ;@ clear all flags, except Z\n");\r
496 ot(" mov r0,r0,asl #24\n");\r
497 ot(" and r2,r2,#0x20000000\n");\r
498 ot(" add r2,r0,r2,lsr #5 ;@ add X\n");\r
499 ot(" rsb r11,r2,#0x9a000000 ;@ do arithmetic\n");\r
500\r
501 ot(" cmp r11,#0x9a000000\n");\r
502 ot(" beq finish%.4x\n",op);\r
503 ot("\n");\r
504\r
505 ot(" mvn r3,r11,lsr #31 ;@ Undefined V behavior\n",op);\r
506 ot(" and r2,r11,#0x0f000000\n");\r
507 ot(" cmp r2,#0x0a000000\n");\r
508 ot(" andeq r11,r11,#0xf0000000\n");\r
509 ot(" addeq r11,r11,#0x10000000\n");\r
510 ot(" and r3,r3,r11,lsr #31 ;@ Undefined V behavior part II\n",op);\r
511 ot(" movs r1,r11,asr #24\n");\r
512 ot(" bicne r10,r10,#0x40000000 ;@ Z\n");\r
513 ot(" orr r10,r10,r3,lsl #28 ;@ save V\n",op);\r
514 ot(" orr r10,r10,#0x20000000 ;@ C\n");\r
515 ot("\n");\r
516\r
517 EaWrite(6, 1, ea,0,0x3f,0,0);\r
518\r
519 ot("finish%.4x%s\n",op,ms?"":":");\r
520 ot(" tst r11,r11\n");\r
521 ot(" orrmi r10,r10,#0x80000000 ;@ N\n");\r
522 ot(" str r10,[r7,#0x4c] ;@ Save X\n");\r
523 ot("\n");\r
524\r
525 ot(" ldr r6,[r7,#0x54]\n");\r
526 OpEnd(ea);\r
527\r
528 return 0;\r
529}\r
530\r
531// --------------------- Opcodes 0x90c0+ ---------------------\r
532// Suba/Cmpa/Adda 1tt1nnnx 11eeeeee (tt=type, x=size, eeeeee=Source EA)\r
533int OpAritha(int op)\r
534{\r
535 int use=0;\r
536 int type=0,size=0,sea=0,dea=0;\r
537 const char *asr="";\r
538\r
539 // Suba/Cmpa/Adda/(invalid):\r
540 type=(op>>13)&3; if (type>=3) return 1;\r
541\r
542 size=(op>>8)&1; size++;\r
543 dea=(op>>9)&7; dea|=8; // Dest=An\r
544 sea=op&0x003f; // Source\r
545\r
546 // See if we can do this opcode:\r
547 if (EaCanRead(sea,size)==0) return 1;\r
548\r
549 use=OpBase(op,size);\r
550 use&=~0x0e00; // Use same opcode for An\r
551 if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r
552\r
553 OpStart(op,sea); Cycles=(size==2)?6:8;\r
554 if(size==2&&(sea<0x10||sea==0x3c)) Cycles+=2;\r
555 if(type==1) Cycles=6;\r
556\r
557 // EA calculation order defines how situations like suba.w (A0)+, A0 get handled.\r
558 // different emus act differently in this situation, I couldn't fugure which is right behaviour.\r
559 //if (type == 1)\r
560 {\r
561 EaCalcReadNoSE(-1,0,sea,size,0x003f);\r
562 EaCalcReadNoSE(type!=1?11:-1,1,dea,2,0x0e00);\r
563 }\r
564#if 0\r
565 else\r
566 {\r
567 EaCalcReadNoSE(type!=1?11:-1,1,dea,2,0x0e00);\r
568 EaCalcReadNoSE(-1,0,sea,size,0x003f);\r
569 }\r
570#endif\r
571\r
572 if (size<2) ot(" mov r0,r0,asl #%d\n\n",size?16:24);\r
573 if (size<2) asr=(char *)(size?",asr #16":",asr #24");\r
574\r
575 if (type==0) ot(" sub r1,r1,r0%s\n",asr);\r
576 if (type==1) ot(" cmp r1,r0%s ;@ Defines NZCV\n",asr);\r
577 if (type==1) OpGetFlags(1,0); // Get Cmp flags\r
578 if (type==2) ot(" add r1,r1,r0%s\n",asr);\r
579 ot("\n");\r
580\r
581 if (type!=1) EaWrite(11, 1, dea,2,0x0e00);\r
582\r
583 OpEnd(sea);\r
584\r
585 return 0;\r
586}\r
587\r
588// --------------------- Opcodes 0x9100+ ---------------------\r
589// Emit a Subx/Addx opcode, 1t01ddd1 zz00rsss addx.z Ds,Dd\r
590int OpAddx(int op)\r
591{\r
592 int use=0;\r
593 int type=0,size=0,dea=0,sea=0,mem=0;\r
594 const char *asl="";\r
595\r
596 type=(op>>14)&1;\r
597 dea =(op>> 9)&7;\r
598 size=(op>> 6)&3; if (size>=3) return 1;\r
599 sea = op&7;\r
600 mem =(op>> 3)&1;\r
601\r
602 // See if we can do this opcode:\r
603 if (EaCanRead(sea,size)==0) return 1;\r
604 if (EaCanWrite(dea)==0) return 1;\r
605\r
606 if (mem) { sea+=0x20; dea+=0x20; }\r
607\r
608 use=op&~0x0e07; // Use same opcode for Dn\r
609 if (size==0&&sea==0x27) use|=0x0007; // ___x.b -(a7)\r
610 if (size==0&&dea==0x27) use|=0x0e00; // ___x.b -(a7)\r
611 if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r
612\r
613 OpStart(op,sea,dea); Cycles=4;\r
614 if(size>=2) Cycles+=4;\r
615 if(sea>=0x10) Cycles+=2;\r
616\r
617 if (mem)\r
618 {\r
619 ot(";@ Get src/dest EA vals\n");\r
620 EaCalc (0,0x000f, sea,size,1);\r
621 EaRead (0, 6, sea,size,0x000f,1);\r
622 EaCalcReadNoSE(11,0,dea,size,0x0e00);\r
623 }\r
624 else\r
625 {\r
626 ot(";@ Get src/dest reg vals\n");\r
627 EaCalcReadNoSE(-1,6,sea,size,0x0007);\r
628 EaCalcReadNoSE(11,0,dea,size,0x0e00);\r
629 if (size<2) ot(" mov r6,r6,asl #%d\n\n",size?16:24);\r
630 }\r
631\r
632 if (size<2) asl=(char *)(size?",asl #16":",asl #24");\r
633\r
634 ot(";@ Do arithmetic:\n");\r
635 GetXBit(type==0);\r
636\r
637 if (type==1 && size<2)\r
638 {\r
639 ot(";@ Make sure the carry bit will tip the balance:\n");\r
640 ot(" mvn r2,#0\n");\r
641 ot(" orr r6,r6,r2,lsr #%i\n",(size==0)?8:16);\r
642 ot("\n");\r
643 }\r
644\r
645 if (type==0) ot(" rscs r1,r6,r0%s\n",asl);\r
646 if (type==1) ot(" adcs r1,r6,r0%s\n",asl);\r
647 ot(" orr r3,r10,#0xb0000000 ;@ for old Z\n");\r
648 OpGetFlags(type==0,1,0); // subtract\r
649 if (size<2) {\r
650 ot(" movs r2,r1,lsr #%i\n", size?16:24);\r
651 ot(" orreq r10,r10,#0x40000000 ;@ add potentially missed Z\n");\r
652 }\r
653 ot(" andeq r10,r10,r3 ;@ fix Z\n");\r
654 ot("\n");\r
655\r
656 ot(";@ Save result:\n");\r
657 EaWrite(11, 1, dea,size,0x0e00,1);\r
658\r
659 ot(" ldr r6,[r7,#0x54]\n");\r
660 OpEnd(sea,dea);\r
661\r
662 return 0;\r
663}\r
664\r
665// --------------------- Opcodes 0xb000+ ---------------------\r
666// Emit a Cmp/Eor opcode, 1011rrrt xxeeeeee (rrr=Dn, t=cmp/eor, xx=size extension, eeeeee=ea)\r
667int OpCmpEor(int op)\r
668{\r
669 int rea=0,eor=0;\r
670 int size=0,ea=0,use=0;\r
671 const char *asl="";\r
672\r
673 // Get EA and register EA\r
674 rea=(op>>9)&7;\r
675 eor=(op>>8)&1;\r
676 size=(op>>6)&3; if (size>=3) return 1;\r
677 ea=op&0x3f;\r
678\r
679 if (eor && (ea>>3) == 1) return 1; // not a valid mode for eor\r
680\r
681 // See if we can do this opcode:\r
682 if (EaCanRead(ea,size)==0) return 1;\r
683 if (eor && EaCanWrite(ea)==0) return 1;\r
684 if (EaAn(ea)&&(eor||size==0)) return 1;\r
685\r
686 use=OpBase(op,size);\r
687 use&=~0x0e00; // Use 1 handler for register d0-7\r
688 if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r
689\r
690 OpStart(op,ea); Cycles=4;\r
691 if(eor) {\r
692 if(ea>8) Cycles+=4;\r
693 if(size>=2) Cycles+=4;\r
694 } else {\r
695 if(size>=2) Cycles+=2;\r
696 }\r
697\r
698 ot(";@ Get EA into r11 and value into r0:\n");\r
699 EaCalcReadNoSE(eor?11:-1,0,ea,size,0x003f);\r
700\r
701 ot(";@ Get register operand into r1:\n");\r
702 EaCalcReadNoSE(-1,1,rea,size,0x0e00);\r
703\r
704 if (size<2) ot(" mov r0,r0,asl #%d\n\n",size?16:24);\r
705 if (size<2) asl=(char *)(size?",asl #16":",asl #24");\r
706\r
707 ot(";@ Do arithmetic:\n");\r
708 if (eor==0) ot(" rsbs r1,r0,r1%s\n",asl);\r
709 if (eor)\r
710 {\r
711 ot(" eor r1,r0,r1%s\n",asl);\r
712 ot(" adds r1,r1,#0 ;@ Defines NZ, clears CV\n");\r
713 }\r
714\r
715 OpGetFlags(eor==0,0); // Cmp like subtract\r
716 ot("\n");\r
717\r
718 if (eor) EaWrite(11, 1,ea,size,0x003f,1);\r
719\r
720 OpEnd(ea);\r
721 return 0;\r
722}\r
723\r
724// Emit a Cmpm opcode, 1011ddd1 xx001sss (rrr=Adst, xx=size extension, sss=Asrc)\r
725int OpCmpm(int op)\r
726{\r
727 int size=0,sea=0,dea=0,use=0;\r
728 const char *asl="";\r
729\r
730 // get size, get EAs\r
731 size=(op>>6)&3; if (size>=3) return 1;\r
732 sea=(op&7)|0x18;\r
733 dea=(op>>9)&0x3f;\r
734\r
735 use=op&~0x0e07; // Use 1 handler for all registers..\r
736 if (size==0&&sea==0x1f) use|=0x0007; // ..except (a7)+\r
737 if (size==0&&dea==0x1f) use|=0x0e00;\r
738 if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r
739\r
740 OpStart(op,sea); Cycles=4;\r
741\r
742 ot(";@ Get src operand into r11:\n");\r
743 EaCalc (0,0x0007, sea,size,1);\r
744 EaRead (0, 11, sea,size,0x0007,1);\r
745\r
746 ot(";@ Get dst operand into r0:\n");\r
747 EaCalcReadNoSE(-1,0,dea,size,0x0e00);\r
748\r
749 if (size<2) asl=(char *)(size?",asl #16":",asl #24");\r
750\r
751 ot(" rsbs r0,r11,r0%s\n",asl);\r
752 OpGetFlags(1,0); // Cmp like subtract\r
753 ot("\n");\r
754\r
755 OpEnd(sea);\r
756 return 0;\r
757}\r
758\r
759\r
760// Emit a Chk opcode, 0100ddd1 x0eeeeee (rrr=Dn, x=size extension, eeeeee=ea)\r
761int OpChk(int op)\r
762{\r
763 int rea=0;\r
764 int size=0,ea=0,use=0;\r
765\r
766 // Get EA and register EA\r
767 rea=(op>>9)&7;\r
768 if((op>>7)&1)\r
769 size=1; // word operation\r
770 else size=2; // long\r
771 ea=op&0x3f;\r
772\r
773 if (EaAn(ea)) return 1; // not a valid mode\r
774 if (size!=1) return 1; // 000 variant only supports word\r
775\r
776 // See if we can do this opcode:\r
777 if (EaCanRead(ea,size)==0) return 1;\r
778\r
779 use=OpBase(op,size);\r
780 use&=~0x0e00; // Use 1 handler for register d0-7\r
781 if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r
782\r
783 OpStart(op,ea); Cycles=10;\r
784\r
785 ot(";@ Get value into r0:\n");\r
786 EaCalcReadNoSE(-1,0,ea,size,0x003f);\r
787\r
788 ot(";@ Get register operand into r1:\n");\r
789 EaCalcReadNoSE(-1,1,rea,size,0x0e00);\r
790\r
791 if (size<2) ot(" mov r0,r0,asl #%d\n",size?16:24);\r
792 if (size<2) ot(" mov r1,r1,asl #%d\n\n",size?16:24);\r
793\r
794 ot(";@ get flags, including undocumented ones\n");\r
795 ot(" and r3,r10,#0x80000000\n");\r
796 ot(" adds r1,r1,#0 ;@ Defines NZ, clears CV\n");\r
797 OpGetFlags(0,0);\r
798\r
799 ot(";@ is reg negative?\n");\r
800 ot(" bmi chktrap%.4x\n",op);\r
801\r
802 ot(";@ Do arithmetic:\n");\r
803 ot(" bic r10,r10,#0x80000000 ;@ N\n");\r
804 ot(" cmp r1,r0\n");\r
805 ot(" bgt chktrap%.4x\n",op);\r
806\r
807 ot(";@ old N remains\n");\r
808 ot(" orr r10,r10,r3\n");\r
809 OpEnd(ea);\r
810\r
811 ot("chktrap%.4x%s ;@ CHK exception:\n",op,ms?"":":");\r
812 ot(" mov r0,#6\n");\r
813 ot(" bl Exception\n");\r
814 Cycles+=40;\r
815 OpEnd(ea);\r
816\r
817 return 0;\r
818}\r
819\r
fast MegaDrive/MegaCD/32X emulator