| 1 | \r |
| 2 | // This file is part of the Cyclone 68000 Emulator\r |
| 3 | \r |
| 4 | // Copyright (c) 2011 FinalDave (emudave (at) gmail.com)\r |
| 5 | \r |
| 6 | // This code is licensed under the GNU General Public License version 2.0 and the MAME License.\r |
| 7 | // You can choose the license that has the most advantages for you.\r |
| 8 | \r |
| 9 | // SVN repository can be found at http://code.google.com/p/cyclone68000/\r |
| 10 | \r |
| 11 | #include "app.h"\r |
| 12 | \r |
| 13 | // --------------------- Opcodes 0x0100+ ---------------------\r |
| 14 | // Emit a Btst (Register) opcode 0000nnn1 00aaaaaa\r |
| 15 | int OpBtstReg(int op)\r |
| 16 | {\r |
| 17 | int use=0;\r |
| 18 | int type=0,sea=0,tea=0;\r |
| 19 | int size=0;\r |
| 20 | \r |
| 21 | type=(op>>6)&3;\r |
| 22 | // Get source and target EA\r |
| 23 | sea=(op>>9)&7;\r |
| 24 | tea=op&0x003f;\r |
| 25 | if (tea<0x10) size=2; // For registers, 32-bits\r |
| 26 | \r |
| 27 | if ((tea&0x38)==0x08) return 1; // movep\r |
| 28 | \r |
| 29 | // See if we can do this opcode:\r |
| 30 | if (EaCanRead(tea,0)==0) return 1;\r |
| 31 | if (type>0)\r |
| 32 | {\r |
| 33 | if (EaCanWrite(tea)==0) return 1;\r |
| 34 | }\r |
| 35 | \r |
| 36 | use=OpBase(op);\r |
| 37 | use&=~0x0e00; // Use same handler for all registers\r |
| 38 | if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r |
| 39 | \r |
| 40 | OpStart(op); Cycles=4;\r |
| 41 | if (tea<0x10) Cycles+=2;\r |
| 42 | if (type>0) Cycles+=4;\r |
| 43 | \r |
| 44 | ot(" mov r10,#1\n");\r |
| 45 | \r |
| 46 | EaCalc (0,0x0e00,sea,0);\r |
| 47 | EaRead (0, 0,sea,0);\r |
| 48 | ot(" bic r9,r9,#0x40000000 ;@ Blank Z flag\n");\r |
| 49 | ot(" mov r10,r10,lsl r0 ;@ Make bit mask\n");\r |
| 50 | ot("\n");\r |
| 51 | \r |
| 52 | EaCalc(11,0x003f,tea,size);\r |
| 53 | EaRead(11, 0,tea,size);\r |
| 54 | ot(" tst r0,r10 ;@ Do arithmetic\n");\r |
| 55 | ot(" orreq r9,r9,#0x40000000 ;@ Get Z flag\n");\r |
| 56 | ot("\n");\r |
| 57 | \r |
| 58 | if (type>0)\r |
| 59 | {\r |
| 60 | if (type==1) ot(" eor r1,r0,r10 ;@ Toggle bit\n");\r |
| 61 | if (type==2) ot(" bic r1,r0,r10 ;@ Clear bit\n");\r |
| 62 | if (type==3) ot(" orr r1,r0,r10 ;@ Set bit\n");\r |
| 63 | ot("\n");\r |
| 64 | EaWrite(11, 1,tea,size);\r |
| 65 | }\r |
| 66 | OpEnd();\r |
| 67 | \r |
| 68 | return 0;\r |
| 69 | }\r |
| 70 | \r |
| 71 | // --------------------- Opcodes 0x0800+ ---------------------\r |
| 72 | // Emit a Btst/Bchg/Bclr/Bset (Immediate) opcode 00001000 ttaaaaaa nn\r |
| 73 | int OpBtstImm(int op)\r |
| 74 | {\r |
| 75 | int type=0,sea=0,tea=0;\r |
| 76 | int use=0;\r |
| 77 | int size=0;\r |
| 78 | \r |
| 79 | type=(op>>6)&3;\r |
| 80 | // Get source and target EA\r |
| 81 | sea= 0x003c;\r |
| 82 | tea=op&0x003f;\r |
| 83 | if (tea<0x10) size=2; // For registers, 32-bits\r |
| 84 | \r |
| 85 | // See if we can do this opcode:\r |
| 86 | if (EaCanRead(tea,0)==0) return 1;\r |
| 87 | if (type>0)\r |
| 88 | {\r |
| 89 | if (EaCanWrite(tea)==0) return 1;\r |
| 90 | }\r |
| 91 | \r |
| 92 | use=OpBase(op);\r |
| 93 | if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r |
| 94 | \r |
| 95 | OpStart(op); Cycles=4;\r |
| 96 | if (type<3 && tea<0x10) Cycles+=2;\r |
| 97 | if (type>0) Cycles+=4;\r |
| 98 | \r |
| 99 | ot(" mov r10,#1\n");\r |
| 100 | ot("\n");\r |
| 101 | EaCalc ( 0,0x0000,sea,0);\r |
| 102 | EaRead ( 0, 0,sea,0);\r |
| 103 | ot(" bic r9,r9,#0x40000000 ;@ Blank Z flag\n");\r |
| 104 | ot(" mov r10,r10,lsl r0 ;@ Make bit mask\n");\r |
| 105 | ot("\n");\r |
| 106 | \r |
| 107 | EaCalc (11,0x003f,tea,size);\r |
| 108 | EaRead (11, 0,tea,size);\r |
| 109 | ot(" tst r0,r10 ;@ Do arithmetic\n");\r |
| 110 | ot(" orreq r9,r9,#0x40000000 ;@ Get Z flag\n");\r |
| 111 | ot("\n");\r |
| 112 | \r |
| 113 | if (type>0)\r |
| 114 | {\r |
| 115 | if (type==1) ot(" eor r1,r0,r10 ;@ Toggle bit\n");\r |
| 116 | if (type==2) ot(" bic r1,r0,r10 ;@ Clear bit\n");\r |
| 117 | if (type==3) ot(" orr r1,r0,r10 ;@ Set bit\n");\r |
| 118 | ot("\n");\r |
| 119 | EaWrite(11, 1,tea,size);\r |
| 120 | }\r |
| 121 | \r |
| 122 | OpEnd();\r |
| 123 | \r |
| 124 | return 0;\r |
| 125 | }\r |
| 126 | \r |
| 127 | // --------------------- Opcodes 0x4000+ ---------------------\r |
| 128 | int OpNeg(int op)\r |
| 129 | {\r |
| 130 | // 01000tt0 xxeeeeee (tt=negx/clr/neg/not, xx=size, eeeeee=EA)\r |
| 131 | int type=0,size=0,ea=0,use=0;\r |
| 132 | \r |
| 133 | type=(op>>9)&3;\r |
| 134 | ea =op&0x003f;\r |
| 135 | size=(op>>6)&3; if (size>=3) return 1;\r |
| 136 | \r |
| 137 | switch (type)\r |
| 138 | {\r |
| 139 | case 1: case 2: case 3: break;\r |
| 140 | default: return 1; // todo\r |
| 141 | }\r |
| 142 | \r |
| 143 | // See if we can do this opcode:\r |
| 144 | if (EaCanRead (ea,size)==0) return 1;\r |
| 145 | if (EaCanWrite(ea )==0) return 1;\r |
| 146 | \r |
| 147 | use=OpBase(op);\r |
| 148 | if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r |
| 149 | \r |
| 150 | OpStart(op); Cycles=size<2?4:6;\r |
| 151 | \r |
| 152 | EaCalc (10,0x003f,ea,size);\r |
| 153 | \r |
| 154 | if (type!=1) EaRead (10,0,ea,size); // Don't need to read for 'clr'\r |
| 155 | if (type==1) ot("\n");\r |
| 156 | \r |
| 157 | if (type==1)\r |
| 158 | {\r |
| 159 | ot(";@ Clear:\n");\r |
| 160 | ot(" mov r1,#0\n");\r |
| 161 | ot(" mov r9,#0x40000000 ;@ NZCV=0100\n");\r |
| 162 | ot("\n");\r |
| 163 | }\r |
| 164 | \r |
| 165 | if (type==2)\r |
| 166 | {\r |
| 167 | ot(";@ Neg:\n");\r |
| 168 | ot(" rsbs r1,r0,#0\n");\r |
| 169 | OpGetFlags(1,1);\r |
| 170 | ot("\n");\r |
| 171 | }\r |
| 172 | \r |
| 173 | if (type==3)\r |
| 174 | {\r |
| 175 | ot(";@ Not:\n");\r |
| 176 | ot(" mvn r1,r0\n");\r |
| 177 | ot(" adds r1,r1,#0 ;@ Defines NZ, clears CV\n");\r |
| 178 | OpGetFlags(0,0);\r |
| 179 | ot("\n");\r |
| 180 | }\r |
| 181 | \r |
| 182 | EaWrite(10, 1,ea,size);\r |
| 183 | \r |
| 184 | OpEnd();\r |
| 185 | \r |
| 186 | return 0;\r |
| 187 | }\r |
| 188 | \r |
| 189 | // --------------------- Opcodes 0x4840+ ---------------------\r |
| 190 | // Swap, 01001000 01000nnn swap Dn\r |
| 191 | int OpSwap(int op)\r |
| 192 | {\r |
| 193 | int ea=0,use=0;\r |
| 194 | \r |
| 195 | ea=op&7;\r |
| 196 | use=op&~0x0007; // Use same opcode for all An\r |
| 197 | \r |
| 198 | if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r |
| 199 | \r |
| 200 | OpStart(op); Cycles=4;\r |
| 201 | \r |
| 202 | EaCalc (10,0x0007,ea,2);\r |
| 203 | EaRead (10, 0,ea,2);\r |
| 204 | \r |
| 205 | ot(" mov r1,r0,ror #16\n");\r |
| 206 | ot(" adds r1,r1,#0 ;@ Defines NZ, clears CV\n");\r |
| 207 | OpGetFlags(0,0);\r |
| 208 | \r |
| 209 | EaWrite(10, 1,8,2);\r |
| 210 | \r |
| 211 | OpEnd();\r |
| 212 | \r |
| 213 | return 0;\r |
| 214 | }\r |
| 215 | \r |
| 216 | // --------------------- Opcodes 0x4a00+ ---------------------\r |
| 217 | // Emit a Tst opcode, 01001010 xxeeeeee\r |
| 218 | int OpTst(int op)\r |
| 219 | {\r |
| 220 | int sea=0;\r |
| 221 | int size=0,use=0;\r |
| 222 | \r |
| 223 | sea=op&0x003f;\r |
| 224 | size=(op>>6)&3; if (size>=3) return 1;\r |
| 225 | \r |
| 226 | // See if we can do this opcode:\r |
| 227 | if (EaCanWrite(sea)==0) return 1;\r |
| 228 | \r |
| 229 | use=OpBase(op);\r |
| 230 | if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r |
| 231 | \r |
| 232 | OpStart(op); Cycles=4;\r |
| 233 | \r |
| 234 | EaCalc ( 0,0x003f,sea,size);\r |
| 235 | EaRead ( 0, 0,sea,size);\r |
| 236 | \r |
| 237 | ot(" adds r0,r0,#0 ;@ Defines NZ, clears CV\n");\r |
| 238 | ot(" mrs r9,cpsr ;@ r9=flags\n");\r |
| 239 | ot("\n");\r |
| 240 | \r |
| 241 | OpEnd();\r |
| 242 | return 0;\r |
| 243 | }\r |
| 244 | \r |
| 245 | // --------------------- Opcodes 0x4880+ ---------------------\r |
| 246 | // Emit an Ext opcode, 01001000 1x000nnn\r |
| 247 | int OpExt(int op)\r |
| 248 | {\r |
| 249 | int ea=0;\r |
| 250 | int size=0,use=0;\r |
| 251 | int shift=0;\r |
| 252 | \r |
| 253 | ea=op&0x0007;\r |
| 254 | size=(op>>6)&1;\r |
| 255 | shift=32-(8<<size);\r |
| 256 | \r |
| 257 | use=OpBase(op);\r |
| 258 | if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r |
| 259 | \r |
| 260 | OpStart(op); Cycles=4;\r |
| 261 | \r |
| 262 | EaCalc (10,0x0007,ea,size+1);\r |
| 263 | EaRead (10, 0,ea,size+1);\r |
| 264 | \r |
| 265 | ot(" mov r0,r0,asl #%d\n",shift);\r |
| 266 | ot(" adds r0,r0,#0 ;@ Defines NZ, clears CV\n");\r |
| 267 | ot(" mrs r9,cpsr ;@ r9=flags\n");\r |
| 268 | ot(" mov r1,r0,asr #%d\n",shift);\r |
| 269 | ot("\n");\r |
| 270 | \r |
| 271 | EaWrite(10, 1,ea,size+1);\r |
| 272 | \r |
| 273 | OpEnd();\r |
| 274 | return 0;\r |
| 275 | }\r |
| 276 | \r |
| 277 | // --------------------- Opcodes 0x50c0+ ---------------------\r |
| 278 | // Emit a Set cc opcode, 0101cccc 11eeeeee\r |
| 279 | int OpSet(int op)\r |
| 280 | {\r |
| 281 | int cc=0,ea=0;\r |
| 282 | int size=0,use=0;\r |
| 283 | char *cond[16]=\r |
| 284 | {\r |
| 285 | "al","", "hi","ls","cc","cs","ne","eq",\r |
| 286 | "vc","vs","pl","mi","ge","lt","gt","le"\r |
| 287 | };\r |
| 288 | \r |
| 289 | cc=(op>>8)&15;\r |
| 290 | ea=op&0x003f;\r |
| 291 | \r |
| 292 | if ((ea&0x38)==0x08) return 1; // dbra, not scc\r |
| 293 | \r |
| 294 | // See if we can do this opcode:\r |
| 295 | if (EaCanWrite(ea)==0) return 1;\r |
| 296 | \r |
| 297 | use=OpBase(op);\r |
| 298 | if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r |
| 299 | \r |
| 300 | OpStart(op); Cycles=8;\r |
| 301 | \r |
| 302 | if (ea<0x10) Cycles=4;\r |
| 303 | \r |
| 304 | ot(" mov r1,#0\n");\r |
| 305 | \r |
| 306 | if (cc!=1)\r |
| 307 | {\r |
| 308 | ot(";@ Is the condition true?\n");\r |
| 309 | if ((cc&~1)==2) ot(" eor r9,r9,#0x20000000 ;@ Invert carry for hi/ls\n");\r |
| 310 | ot(" msr cpsr_flg,r9 ;@ ARM flags = 68000 flags\n");\r |
| 311 | if ((cc&~1)==2) ot(" eor r9,r9,#0x20000000 ;@ Invert carry for hi/ls\n");\r |
| 312 | ot(" mvn%s r1,r1\n",cond[cc]);\r |
| 313 | }\r |
| 314 | \r |
| 315 | if (ea<0x10) ot(" sub%s r5,r5,#2 ;@ Extra cycles\n",cond[cc]);\r |
| 316 | ot("\n");\r |
| 317 | \r |
| 318 | EaCalc (0,0x003f, ea,size);\r |
| 319 | EaWrite(0, 1, ea,size);\r |
| 320 | \r |
| 321 | OpEnd();\r |
| 322 | return 0;\r |
| 323 | }\r |
| 324 | \r |
| 325 | // Emit a Asr/Lsr/Roxr/Ror opcode\r |
| 326 | static int EmitAsr(int op,int type,int dir,int count,int size,int usereg)\r |
| 327 | {\r |
| 328 | char pct[8]="";\r |
| 329 | int shift=32-(8<<size);\r |
| 330 | \r |
| 331 | if (count>=1) sprintf(pct,"#%d",count); // Fixed count\r |
| 332 | \r |
| 333 | if (count<0)\r |
| 334 | {\r |
| 335 | ot(" mov r2,r8,lsr #9 ;@ Get 'n'\n");\r |
| 336 | ot(" and r2,r2,#7\n\n"); strcpy(pct,"r2");\r |
| 337 | }\r |
| 338 | \r |
| 339 | if (usereg)\r |
| 340 | {\r |
| 341 | ot(";@ Use Dn for count:\n");\r |
| 342 | ot(" ldr r2,[r7,r2,lsl #2]\n");\r |
| 343 | ot(" and r2,r2,#63\n");\r |
| 344 | ot("\n");\r |
| 345 | }\r |
| 346 | \r |
| 347 | // Take 2*n cycles:\r |
| 348 | if (count<0) ot(" sub r5,r5,r2,asl #1 ;@ Take 2*n cycles\n\n");\r |
| 349 | else Cycles+=count<<1;\r |
| 350 | \r |
| 351 | if (type<2)\r |
| 352 | {\r |
| 353 | // Asr/Lsr\r |
| 354 | if (dir==0 && size<2)\r |
| 355 | {\r |
| 356 | ot(";@ For shift right, also copy to lowest bits (to get carry bit):\n");\r |
| 357 | ot(" orr r0,r0,r0,lsr #%d\n",32-(8<<size));\r |
| 358 | ot("\n");\r |
| 359 | }\r |
| 360 | \r |
| 361 | ot(";@ Shift register:\n");\r |
| 362 | if (type==0) ot(" movs r0,r0,%s %s\n",dir?"asl":"asr",pct);\r |
| 363 | if (type==1) ot(" movs r0,r0,%s %s\n",dir?"lsl":"lsr",pct);\r |
| 364 | OpGetFlags(0,1);\r |
| 365 | ot("\n");\r |
| 366 | \r |
| 367 | if (size<2)\r |
| 368 | {\r |
| 369 | ot(";@ Check if result is zero:\n");\r |
| 370 | ot(" movs r2,r0,lsr #%d\n",shift);\r |
| 371 | ot(" orreq r9,r9,#0x40000000\n");\r |
| 372 | ot("\n");\r |
| 373 | }\r |
| 374 | }\r |
| 375 | \r |
| 376 | // --------------------------------------\r |
| 377 | if (type==2)\r |
| 378 | {\r |
| 379 | // Roxr\r |
| 380 | int wide=8<<size;\r |
| 381 | \r |
| 382 | if (shift) ot(" mov r0,r0,lsr #%d ;@ Shift down\n",shift);\r |
| 383 | \r |
| 384 | ot(";@ Rotate register through X:\n");\r |
| 385 | if (strcmp("r2",pct)!=0) { ot(" mov r2,%s\n",pct); strcpy(pct,"r2"); } // Get into register\r |
| 386 | \r |
| 387 | if (count!=8)\r |
| 388 | {\r |
| 389 | ot(";@ Reduce r2 until <0:\n");\r |
| 390 | ot("Reduce_%.4x%s\n",op,ms?"":":");\r |
| 391 | ot(" subs r2,r2,#%d\n",wide+1);\r |
| 392 | ot(" bpl Reduce_%.4x\n",op);\r |
| 393 | ot(" add r2,r2,#%d ;@ Now r2=0-%d\n",wide+1,wide);\r |
| 394 | ot("\n");\r |
| 395 | }\r |
| 396 | \r |
| 397 | if (dir) ot(" rsb r2,r2,#%d ;@ Reverse direction\n",wide+1);\r |
| 398 | \r |
| 399 | ot(";@ Rotate bits:\n");\r |
| 400 | ot(" mov r3,r0,lsr r2 ;@ Get right part\n");\r |
| 401 | ot(" rsb r2,r2,#%d\n",wide+1);\r |
| 402 | ot(" movs r0,r0,lsl r2 ;@ Get left part\n");\r |
| 403 | ot(" orr r0,r3,r0 ;@ r0=Rotated value\n");\r |
| 404 | \r |
| 405 | ot(";@ Insert X bit into r2-1:\n");\r |
| 406 | ot(" ldrb r3,[r7,#0x45]\n");\r |
| 407 | ot(" sub r2,r2,#1\n");\r |
| 408 | ot(" and r3,r3,#2\n");\r |
| 409 | ot(" mov r3,r3,lsr #1\n");\r |
| 410 | ot(" orr r0,r0,r3,lsl r2\n");\r |
| 411 | ot("\n");\r |
| 412 | \r |
| 413 | if (shift) ot(" movs r0,r0,lsl #%d ;@ Shift up and get correct NC flags\n",shift);\r |
| 414 | OpGetFlags(0,1);\r |
| 415 | ot("\n");\r |
| 416 | }\r |
| 417 | \r |
| 418 | // --------------------------------------\r |
| 419 | if (type==3)\r |
| 420 | {\r |
| 421 | // Ror\r |
| 422 | if (size<2)\r |
| 423 | {\r |
| 424 | ot(";@ Mirror value in whole 32 bits:\n");\r |
| 425 | if (size<=0) ot(" orr r0,r0,r0,lsr #8\n");\r |
| 426 | if (size<=1) ot(" orr r0,r0,r0,lsr #16\n");\r |
| 427 | ot("\n");\r |
| 428 | }\r |
| 429 | \r |
| 430 | ot(";@ Rotate register:\n");\r |
| 431 | if (count<0)\r |
| 432 | {\r |
| 433 | if (dir) ot(" rsb r2,%s,#32\n",pct);\r |
| 434 | ot(" movs r0,r0,ror %s\n",pct);\r |
| 435 | }\r |
| 436 | else\r |
| 437 | {\r |
| 438 | int ror=count;\r |
| 439 | if (dir) ror=32-ror;\r |
| 440 | if (ror&31) ot(" movs r0,r0,ror #%d\n",ror);\r |
| 441 | }\r |
| 442 | \r |
| 443 | if (dir)\r |
| 444 | {\r |
| 445 | ot(";@ Get carry bit from bit 0:\n");\r |
| 446 | ot(" mov r9,#0\n");\r |
| 447 | ot(" ands r2,r0,#1\n");\r |
| 448 | ot(" orrne r9,r9,#0x20000000\n");\r |
| 449 | }\r |
| 450 | else\r |
| 451 | {\r |
| 452 | OpGetFlags(0,0);\r |
| 453 | }\r |
| 454 | ot("\n");\r |
| 455 | \r |
| 456 | }\r |
| 457 | // --------------------------------------\r |
| 458 | \r |
| 459 | return 0;\r |
| 460 | }\r |
| 461 | \r |
| 462 | // Emit a Asr/Lsr/Roxr/Ror opcode - 1110cccd xxuttnnn\r |
| 463 | // (ccc=count, d=direction xx=size extension, u=use reg for count, tt=type, nnn=register Dn)\r |
| 464 | int OpAsr(int op)\r |
| 465 | {\r |
| 466 | int ea=0,use=0;\r |
| 467 | int count=0,dir=0;\r |
| 468 | int size=0,usereg=0,type=0;\r |
| 469 | \r |
| 470 | ea=0;\r |
| 471 | count =(op>>9)&7;\r |
| 472 | dir =(op>>8)&1;\r |
| 473 | size =(op>>6)&3;\r |
| 474 | if (size>=3) return 1; // todo Asr EA\r |
| 475 | usereg=(op>>5)&1;\r |
| 476 | type =(op>>3)&3;\r |
| 477 | \r |
| 478 | if (usereg==0) count=((count-1)&7)+1; // because ccc=000 means 8\r |
| 479 | \r |
| 480 | // Use the same opcode for target registers:\r |
| 481 | use=op&~0x0007;\r |
| 482 | \r |
| 483 | // As long as count is not 8, use the same opcode for all shift counts::\r |
| 484 | if (usereg==0 && count!=8) { use|=0x0e00; count=-1; }\r |
| 485 | if (usereg) { use&=~0x0e00; count=-1; } // Use same opcode for all Dn\r |
| 486 | \r |
| 487 | if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r |
| 488 | \r |
| 489 | OpStart(op); Cycles=size<2?6:8;\r |
| 490 | \r |
| 491 | EaCalc(10,0x0007, ea,size);\r |
| 492 | EaRead(10, 0, ea,size,1);\r |
| 493 | \r |
| 494 | EmitAsr(op,type,dir,count, size,usereg);\r |
| 495 | \r |
| 496 | EaWrite(10, 0, ea,size,1);\r |
| 497 | \r |
| 498 | OpEnd();\r |
| 499 | \r |
| 500 | return 0;\r |
| 501 | }\r |
| 502 | \r |
| 503 | // Asr/l/Ror/l etc EA - 11100ttd 11eeeeee \r |
| 504 | int OpAsrEa(int op)\r |
| 505 | {\r |
| 506 | int use=0,type=0,dir=0,ea=0,size=1;\r |
| 507 | \r |
| 508 | type=(op>>9)&3;\r |
| 509 | dir =(op>>8)&1;\r |
| 510 | ea = op&0x3f;\r |
| 511 | \r |
| 512 | if (ea<0x10) return 1;\r |
| 513 | // See if we can do this opcode:\r |
| 514 | if (EaCanRead(ea,0)==0) return 1;\r |
| 515 | if (EaCanWrite(ea)==0) return 1;\r |
| 516 | \r |
| 517 | use=OpBase(op);\r |
| 518 | if (op!=use) { OpUse(op,use); return 0; } // Use existing handler\r |
| 519 | \r |
| 520 | OpStart(op); Cycles=8;\r |
| 521 | \r |
| 522 | EaCalc (10,0x003f,ea,size);\r |
| 523 | EaRead (10, 0,ea,size,1);\r |
| 524 | \r |
| 525 | EmitAsr(op,type,dir,1, size,0);\r |
| 526 | \r |
| 527 | ot(";@ Save shifted value back to EA:\n");\r |
| 528 | ot(" mov r1,r0\n");\r |
| 529 | EaWrite(10, 1,ea,size,1);\r |
| 530 | \r |
| 531 | OpEnd();\r |
| 532 | return 0;\r |
| 533 | }\r |