Shamusworld >> Repos - rmac/blob - parmode.h

   1 //
   2 // RMAC - Reboot's Macro Assembler for all Atari computers
   3 // PARMODE.C - Addressing Modes Parser Include
   4 // Copyright (C) 199x Landon Dyer, 2011-2020 Reboot and Friends
   5 // RMAC derived from MADMAC v1.07 Written by Landon Dyer, 1986
   6 // Source utilised with the kind permission of Landon Dyer
   7 //
   8
   9 // This file is included (twice) to parse two addressing modes, into slightly
  10 // different var names
  11 {
  12         uint64_t scaleval;                      // Expression's value
  13         TOKEN scaleexpr[EXPRSIZE];      // Expression
  14         WORD scaleattr;                         // Expression's attribute
  15         SYM * scaleesym;                        // External symbol involved in expr
  16
  17         // Dn
  18         // An
  19         // # expression
  20         if ((*tok >= KW_D0) && (*tok <= KW_D7))
  21         {
  22                 AMn = DREG;
  23                 AnREG = *tok++ & 7;
  24         }
  25         else if ((*tok >= KW_A0) && (*tok <= KW_A7))
  26         {
  27                 AMn = AREG;
  28                 AnREG = *tok++ & 7;
  29         }
  30         else if (*tok == '#')
  31         {
  32                 tok++;
  33
  34                 if (expr(AnEXPR, &AnEXVAL, &AnEXATTR, &AnESYM) != OK)
  35                         return ERROR;
  36
  37                 AMn = IMMED;
  38         }
  39
  40         // Small problem with this is that the opening parentheses might be an
  41         // expression that's part of a displacement; this code will falsely flag
  42         // that as an error.
  43
  44         // (An)
  45         // (An)+
  46         // (An,Xn[.siz][*scale])
  47         // (PC,Xn[.siz][*scale])
  48         // (d16,An)
  49         // (d8,An,Xn[.siz][*scale])
  50         // (d16,PC)
  51         // (d8,PC,Xn[.siz][*scale])
  52         // ([bd,An],Xn[.siz][*scale],od)
  53         // ([bd,An,Xn[.siz][*scale]],od)
  54         // ([bd,PC],Xn[.siz][*scale],od)
  55         // ([bd,PC,Xn[.siz][*scale]],od)
  56         else if (*tok == '(')
  57         {
  58                 int ea_PC = 0;                          // Flag that let us know if we have PC or An relative ea
  59                 tok++;
  60
  61                 if ((*tok >= KW_A0) && (*tok <= KW_A7))
  62                 {
  63                         AnREG = *tok++ & 7;
  64
  65                         if (*tok == ')')
  66                         {
  67                                 tok++;
  68
  69                                 if (*tok == '+')
  70                                 {
  71                                         tok++;
  72                                         AMn = APOSTINC;
  73                                 }
  74                                 else
  75                                         AMn = AIND;
  76
  77                                 goto AnOK;
  78                         }
  79
  80                         AMn = AINDEXED;
  81                         goto AMn_IX0;            // Handle ",Xn[.siz][*scale])"
  82                 }
  83                 else if ((*tok >= KW_D0) && (*tok <= KW_D7))
  84                 {
  85                         // Since index register isn't used here, store register number in this field
  86                         AnIXREG = *tok++ & 7;                                // (Dn)
  87
  88                         if (*tok == ')')
  89                         {
  90                                 tok++;
  91                                 AnEXTEN |= EXT_FULLWORD;    // Definitely using full extension format, so set bit 8
  92                                 AnEXTEN |= EXT_BS;          // Base register suppressed
  93                                 AnEXTEN |= EXT_BDSIZE0;     // Base displacement null
  94                                 AnEXTEN |= EXT_IISPOSN;     // Indirect Postindexed with Null Outer Displacement
  95                                 AMn = MEMPOST;
  96                                 AnREG = 6 << 3;         // stuff 110 to mode field
  97                                 goto AnOK;
  98                         }
  99                         else if (*tok == 'L')
 100                         {
 101                                 AMn = DINDL;                                                                     // (Dn.l)
 102                                 AnEXTEN = 1 << 11;   // Long index size
 103                                 tok++;
 104                         }
 105                         else if (*tok == 'W')                                // (Dn.w)
 106                         {
 107                                 AMn = DINDW;
 108                                 AnEXTEN = 0 << 11;   // Word index size
 109                                 tok++;
 110                         }
 111                         else if (*tok == ',')
 112                         {
 113                                 // ([bd,An],Xn..) without bd, An
 114                                 // Base displacement is suppressed
 115                                 AnEXTEN |= EXT_FULLWORD;    // Definitely using full extension format, so set bit 8
 116                                 AnEXTEN |= EXT_BS;          // Base register suppressed
 117                                 AnEXTEN |= EXT_BDSIZE0;
 118                                 AnREG = 6 << 3;         // stuff 110 to mode field
 119                                 tok++;
 120                                 goto CHECKODn;
 121                         }
 122                         else
 123                         {
 124                                 return error("(Dn) error");
 125                         }
 126
 127                         if (*tok == '*')
 128                         {                        // scale: *1, *2, *4, *8
 129                                 tok++;
 130
 131                                 if (*tok == SYMBOL)
 132                                 {
 133                                         if (expr(scaleexpr, &scaleval, &scaleattr, &scaleesym) != OK)
 134                                                 return error("scale factor expression must evaluate");
 135
 136                                         switch (scaleval)
 137                                         {
 138                                         case 1:
 139                                                 break;
 140                                         case 2:
 141                                                 AnIXSIZ |= TIMES2;
 142                                                 AnEXTEN |= 1 << 9;
 143                                                 break;
 144                                         case 4:
 145                                                 AnIXSIZ |= TIMES4;
 146                                                 AnEXTEN |= 2 << 9;
 147                                                 break;
 148                                         case 8:
 149                                                 AnIXSIZ |= TIMES8;
 150                                                 AnEXTEN |= 3 << 9;
 151                                                 break;
 152                                         default:
 153                                                 goto badmode;
 154                                         }
 155                                 }
 156                                 else if (*tok++ != CONST)
 157                                         goto badmode;
 158                                 else
 159                                 {
 160                                         switch ((int)*tok++)
 161                                         {
 162                                         case 1:
 163                                                 break;
 164                                         case 2:
 165                                                 AnIXSIZ |= TIMES2;
 166                                                 AnEXTEN |= 1 << 9;
 167                                                 break;
 168                                         case 4:
 169                                                 AnIXSIZ |= TIMES4;
 170                                                 AnEXTEN |= 2 << 9;
 171                                                 break;
 172                                         case 8:
 173                                                 AnIXSIZ |= TIMES8;
 174                                                 AnEXTEN |= 3 << 9;
 175                                                 break;
 176                                         default:
 177                                                 goto badmode;
 178                                         }
 179
 180                                         tok++;  // Take into account that constants are 64-bit
 181                                 }
 182                         }
 183
 184                         if (*tok == ')')
 185                         {
 186                                 tok++;
 187                                 AnEXTEN |= EXT_FULLWORD;    // Definitely using full extension format, so set bit 8
 188                                 AnEXTEN |= EXT_BS;          // Base register suppressed
 189                                 AnEXTEN |= EXT_BDSIZE0;     // Base displacement null
 190                                 AnEXTEN |= EXT_IISPOSN;     // Indirect Postindexed with Null Outer Displacement
 191                                 AnREG = 6 << 3;         // stuff 110 to mode field
 192                                 AMn = MEMPOST;
 193                                 goto AnOK;
 194                         }
 195                         else if (*tok == ',')
 196                         {
 197                                 tok++;  // eat the comma
 198                                 // It might be (Dn[.wl][*scale],od)
 199                                 // Maybe this is wrong and we have to write some code here
 200                                 // instead of reusing that path...
 201                                 AnEXTEN |= EXT_FULLWORD;        // Definitely using full extension format, so set bit 8
 202                                 AnEXTEN |= EXT_BS;       // Base displacement null - suppressed
 203                                 AnEXTEN |= AnIXREG << 12;
 204                                 goto CHECKODn;
 205                         }
 206                         else
 207                                 return error("unhandled so far");
 208                 }
 209                 else if (*tok == KW_PC)
 210                 {                            // (PC,Xn[.siz][*scale])
 211                         tok++;
 212                         AMn = PCINDEXED;
 213
 214                         // Common index handler; enter here with 'tok' pointing at the
 215                         // comma.
 216
 217 AMn_IX0:                 // Handle indexed with missing expr
 218
 219                         AnEXVAL = 0;
 220                         AnEXATTR = ABS | DEFINED;
 221
 222 AMn_IXN:                 // Handle any indexed (tok -> a comma)
 223
 224                         if (*tok++ != ',')
 225                                 goto badmode;
 226
 227                         if (*tok < KW_D0 || *tok > KW_A7)
 228                                 goto badmode;
 229
 230                         AnIXREG = *tok++ & 15;
 231
 232                         switch ((int)*tok)
 233                         {                        // Index reg size: <empty> | .W | .L
 234                         case DOTW:
 235                                 tok++;
 236                         default:
 237                                 AnIXSIZ = 0;
 238                                 break;
 239                         case DOTL:
 240                                 AnIXSIZ = 0x0800;
 241                                 tok++;
 242                                 break;
 243                         case DOTB:               // .B not allowed here...
 244                                 goto badmode;
 245                         }
 246
 247                         if (*tok == '*')
 248                         {                        // scale: *1, *2, *4, *8
 249                                 tok++;
 250
 251                                 if (*tok == SYMBOL)
 252                                 {
 253                                         if (expr(scaleexpr, &scaleval, &scaleattr, &scaleesym) != OK)
 254                                                 return error("scale factor expression must evaluate");
 255
 256                                         switch (scaleval)
 257                                         {
 258                                         case 1:
 259                                                 break;
 260                                         case 2:
 261                                                 AnIXSIZ |= TIMES2;
 262                                                 break;
 263                                         case 4:
 264                                                 AnIXSIZ |= TIMES4;
 265                                                 break;
 266                                         case 8:
 267                                                 AnIXSIZ |= TIMES8;
 268                                                 break;
 269                                         default:
 270                                                 goto badmode;
 271                                         }
 272                                 }
 273                                 else if (*tok++ != CONST)
 274                                         goto badmode;
 275                                 else
 276                                 {
 277                                         switch ((int)*tok++)
 278                                         {
 279                                         case 1:
 280                                                 break;
 281                                         case 2:
 282                                                 AnIXSIZ |= TIMES2;
 283                                                 break;
 284                                         case 4:
 285                                                 AnIXSIZ |= TIMES4;
 286                                                 break;
 287                                         case 8:
 288                                                 AnIXSIZ |= TIMES8;
 289                                                 break;
 290                                         default:
 291                                                 goto badmode;
 292                                         }
 293
 294                                         tok++;  // Take into account that constants are 64-bit
 295                                 }
 296                         }
 297
 298                         if (*tok == ',')
 299                         {
 300                                 // If we got here we didn't get any [] stuff
 301                                 // so let's suppress base displacement before
 302                                 // branching off
 303                                 tok++;
 304                                 AnEXTEN |= EXT_BDSIZE0;     // Base displacement null - suppressed
 305                                 goto CHECKODn;
 306                         }
 307                         if (*tok++ != ')')         // final ")"
 308                                 goto badmode;
 309
 310                         goto AnOK;
 311                 }
 312                 else if (*tok == '[')
 313                 {                              // ([...
 314                         tok++;
 315                         AnEXTEN |= EXT_FULLWORD;     // Definitely using full extension format, so set bit 8
 316
 317                         // Check to see if base displacement is present
 318                         if (*tok != CONST && *tok != SYMBOL)
 319                         {
 320                                 AnEXTEN |= EXT_BDSIZE0;
 321                         }
 322                         else
 323                         {
 324                                 expr(AnBEXPR, &AnBEXVAL, &AnBEXATTR, &AnESYM);
 325
 326                                 if (CHECK_OPTS(OPT_020_DISP) && (AnBEXVAL == 0) && (AnEXATTR != 0))
 327                                 {
 328                                         // bd = 0 so let's optimise it out
 329                                         AnEXTEN |= EXT_BDSIZE0;
 330                                 }
 331                                 else if (*tok == DOTL)
 332                                 {
 333                                         // ([bd.l,...
 334                                         AnEXTEN |= EXT_BDSIZEL;
 335                                         tok++;
 336                                 }
 337                                 else
 338                                 {
 339                                         // ([bd[.w],... or ([bd,...
 340                                         // Is .W forced here?
 341                                         if (*tok == DOTW)
 342                                         {
 343                                                 AnEXTEN |= EXT_BDSIZEW;
 344                                                 tok++;
 345                                         }
 346                                         else
 347                                         {
 348                                                 // Defined, absolute values from $FFFF8000..$00007FFF
 349                                                 // get optimized to absolute short
 350                                                 if (CHECK_OPTS(OPT_020_DISP)
 351                                                         && ((AnBEXATTR & (TDB | DEFINED)) == DEFINED)
 352                                                         && (((uint32_t)AnBEXVAL + 0x8000) < 0x10000))
 353                                                 {
 354                                                         AnEXTEN |= EXT_BDSIZEW;
 355
 356                                                         if (optim_warn_flag)
 357                                                                 warn("absolute value in base displacement ranging $FFFF8000..$00007FFF optimised to absolute short");
 358                                                 }
 359                                                 else
 360                                                 {
 361                                                         AnEXTEN |= EXT_BDSIZEL;
 362                                                 }
 363                                         }
 364                                 }
 365
 366                                 if (*tok == ',')
 367                                         tok++;
 368                         }
 369
 370                         // Check for address register or PC,
 371                         // suppress base register otherwise
 372
 373                         if (*tok == KW_PC)
 374                         {                                       // ([bd,PC,...
 375                                 ea_PC = 3;                              // Set flag in order to set proper value to AMn below when we can make a decision on ea
 376                                                                                 // (why "3"? Well, MEMPOST is 3 away from PCMPOST, etc. Have a look at amode.h)
 377                                 AnREG = (7 << 3) | 3;   // PC is special case - stuff 011 to register field and 111 to the mode field
 378                                 tok++;
 379                         }
 380                         else if ((*tok >= KW_A0) && (*tok <= KW_A7))
 381                         {                                       // ([bd,An,...
 382                                 AnREG = (6 << 3) | (*tok & 7);
 383                                 tok++;
 384                         }
 385                         else if ((*tok >= KW_D0) && (*tok <= KW_D7))
 386                         {
 387                                 // ([bd,Dn,...
 388                                 AnREG = (6 << 3);
 389                                 AnEXTEN |= ((*tok & 7) << 12);
 390                                 AnEXTEN |= EXT_D;
 391                                 AnEXTEN |= EXT_BS; // Oh look, a data register! Which means that base register is suppressed
 392                                 tok++;
 393
 394                                 // Check for size
 395                                 // ([bd,An/PC],Xn.W/L...)
 396                                 switch ((int)*tok)
 397                                 {
 398                                 // Index reg size: <empty> | .W | .L
 399                                 case DOTW:
 400                                         tok++;
 401                                         break;
 402                                 default:
 403                                         break;
 404                                 case DOTL:
 405                                         AnEXTEN |= EXT_L;
 406                                         tok++;
 407                                         break;
 408                                 case DOTB:
 409                                         // .B not allowed here...
 410                                         goto badmode;
 411                                 }
 412
 413                                 // Check for scale
 414                                 if (*tok == '*')                        // ([bd,An/PC],Xn*...)
 415                                 {                           // scale: *1, *2, *4, *8
 416                                         tok++;
 417
 418                                         if (*tok == SYMBOL)
 419                                         {
 420                                                 if (expr(scaleexpr, &scaleval, &scaleattr, &scaleesym) != OK)
 421                                                         return error("scale factor expression must evaluate");
 422
 423                                                 switch (scaleval)
 424                                                 {
 425                                                 case 1:
 426                                                         break;
 427                                                 case 2:
 428                                                         AnIXSIZ |= TIMES2;
 429                                                         break;
 430                                                 case 4:
 431                                                         AnIXSIZ |= TIMES4;
 432                                                         break;
 433                                                 case 8:
 434                                                         AnIXSIZ |= TIMES8;
 435                                                         break;
 436                                                 default:
 437                                                         goto badmode;
 438                                 }
 439                                         }
 440                                         else if (*tok++ != CONST)
 441                                                 goto badmode;
 442                                         else
 443                                         {
 444                                                 switch ((int)*tok++)
 445                                                 {
 446                                                 case 1:
 447                                                         break;
 448                                                 case 2:
 449                                                         AnIXSIZ |= TIMES2;
 450                                                         break;
 451                                                 case 4:
 452                                                         AnIXSIZ |= TIMES4;
 453                                                         break;
 454                                                 case 8:
 455                                                         AnIXSIZ |= TIMES8;
 456                                                         break;
 457                                                 default:
 458                                                         goto badmode;
 459                                                 }
 460
 461                                                 tok++;  // Take into account that constants are 64-bit
 462                                         }
 463                                 }
 464                                 if (*tok == ']')  // ([bd,Dn]...
 465                                 {
 466                                         tok++;
 467                                         goto IS_SUPPRESSEDn;
 468                                 }
 469                         }
 470                         else if (*tok == ']')
 471                         {
 472                                 // PC and Xn is suppressed
 473                                 AnREG = 6 << 3;         // stuff 110b to mode field
 474                                 AnEXTEN |= EXT_BS;
 475                         }
 476                         else
 477                         {
 478                                 goto badmode;
 479                         }
 480
 481                         // At a crossroads here. We can accept either ([bd,An/PC],... or ([bd,An/PC,Xn*scale],...
 482                         if (*tok == ']')
 483                         {
 484                                 // ([bd,An/PC],Xn,od)
 485                                 // Check for Xn
 486                                 tok++;
 487
 488                                 if (*tok == ')')
 489                                 {
 490                                         // Xn and od are non existent, get out of jail free card
 491                                         tok++;
 492                                         AMn = MEMPRE + ea_PC;                           // ([bc,An,Xn],od) with no Xn and od
 493                                         AnEXTEN |= EXT_IS | EXT_IISPREN;        // Suppress Xn and od
 494                                         goto AnOK;
 495                                 }
 496                                 else if (*tok != ',')
 497                                         return error("comma expected after ]");
 498                                 else
 499                                         tok++;                          // eat the comma
 500
 501                                 if ((*tok >= KW_A0) && (*tok <= KW_A7))
 502                                 {
 503                                         AnIXREG = ((*tok & 7) << 12);
 504                                         AnEXTEN |= EXT_A;
 505                                         tok++;
 506                                 }
 507                                 else if ((*tok >= KW_D0) && (*tok <= KW_D7))
 508                                 {
 509                                         AnEXTEN |= ((*tok & 7) << 12);
 510                                         AnEXTEN |= EXT_D;
 511                                         tok++;
 512                                 }
 513                                 else
 514                                 {
 515                                         // No index found, suppress it
 516                                         AnEXTEN |= EXT_IS;
 517                                         tok--;                                  // Rewind tok to point to the comma
 518                                         goto IS_SUPPRESSEDn;    // https://xkcd.com/292/ - what does he know anyway?
 519                                 }
 520
 521                                 // Check for Xn size
 522                                 // ([bd,An/PC],Xn.W/L...)
 523                                 switch ((int)*tok)
 524                                 {
 525                                 // Index reg size: <empty> | .W | .L
 526                                 case DOTW:
 527                                         tok++;
 528                                         break;
 529                                 case DOTL:
 530                                         AnEXTEN |= EXT_L;
 531                                         tok++;
 532                                         break;
 533                                 case DOTB:
 534                                         // .B not allowed here...
 535                                         goto badmode;
 536                                 default:
 537                                         break;
 538                                 }
 539
 540                                 // Check for Xn scale
 541                                 if (*tok == '*')                   // ([bd,An/PC],Xn*...)
 542                                 {                                  // scale: *1, *2, *4, *8
 543                                         tok++;
 544
 545                                         if (*tok == SYMBOL)
 546                                         {
 547                                                 if (expr(scaleexpr, &scaleval, &scaleattr, &scaleesym) != OK)
 548                                                         return error("scale factor expression must evaluate");
 549                                         }
 550                                         else if (*tok == CONST)
 551                                         {
 552                                                 scaleval = (int)*tok++;
 553                                                 tok++;  // Take into account that constants are 64-bit
 554                                         }
 555                                         else
 556                                                 goto badmode;
 557
 558                                         switch (scaleval)
 559                                         {
 560                                         case 1:
 561                                                 break;
 562                                         case 2:
 563                                                 AnIXSIZ |= TIMES2;
 564                                                 break;
 565                                         case 4:
 566                                                 AnIXSIZ |= TIMES4;
 567                                                 break;
 568                                         case 8:
 569                                                 AnIXSIZ |= TIMES8;
 570                                                 break;
 571                                         default:
 572                                                 goto badmode;
 573                                         }
 574
 575                                 }
 576
 577                                 // Check for od
 578                                 if (*tok == ')')        // ([bd,An/PC],Xn)
 579                                 {
 580                                         // od is non existent, get out of jail free card
 581                                         AMn = MEMPOST + ea_PC;  // let's say it's ([bd,An],Xn,od) with od=0 then
 582                                         AnEXTEN |= EXT_IISPOSN; // No outer displacement
 583                                         tok++;
 584                                         goto AnOK;
 585                                 }
 586                                 else if (*tok != ',')
 587                                         return error("comma expected");
 588                                 else
 589                                         tok++;  // eat the comma
 590
 591 CHECKODn:
 592                                 if (expr(AnEXPR, &AnEXVAL, &AnEXATTR, &AnESYM) != OK)
 593                                         goto badmode;
 594
 595                                 if (CHECK_OPTS(OPT_020_DISP) && (AnEXATTR & DEFINED) && (AnEXVAL == 0))
 596                                 {
 597                                         // od = 0 so optimise it out
 598                                         AMn = MEMPOST + ea_PC;          // let's say it's ([bd,An],Xn,od) with od=0 then
 599                                         AnEXTEN |= EXT_IISPOSN;         // No outer displacement
 600                                         tok++;
 601                                         goto AnOK;
 602                                 }
 603
 604                                 // ([bd,An/PC],Xn,od)
 605                                 // Is .W forced here?
 606                                 if (*tok == DOTW)
 607                                 {
 608                                         tok++;
 609                                         // od[.W]
 610                                         AnEXTEN |= EXT_IISPOSW; // Word outer displacement
 611                                         AMn = MEMPOST + ea_PC;
 612                                 }
 613                                 else
 614                                 {
 615                                         // Is .L forced here?
 616                                         if (*tok == DOTL)
 617                                                 tok++;                          // Doesn't matter, we're going for .L anyway
 618
 619                                         // od.L
 620                                         if (!(AnEXTEN & EXT_BS))
 621                                                 AnEXTEN |= EXT_IISPOSL; // Long outer displacement
 622                                         else
 623                                         {
 624                                                 // bd is suppressed, so sticking the od size in bd
 625                                                 AnEXTEN |= EXT_BDSIZEL;
 626                                                 // And of course the expression has to be copied to
 627                                                 // AnBEXPR instead of AnEXPR. Yay. :-/
 628                                                 int i = 0;
 629
 630                                                 do
 631                                                 {
 632                                                         AnBEXPR[i] = AnEXPR[i];
 633                                                         i++;
 634                                                 } while (AnEXPR[i] != 'E');
 635
 636                                                 AnBEXPR[i] = 'E';
 637                                         }
 638
 639                                         AMn = MEMPOST + ea_PC;
 640
 641                                         // Defined, absolute values from $FFFF8000..$00007FFF get
 642                                         // optimized to absolute short
 643                                         if (CHECK_OPTS(OPT_020_DISP)
 644                                                 && ((AnEXATTR & (TDB | DEFINED)) == DEFINED)
 645                                                 && (((uint32_t)AnEXVAL + 0x8000) < 0x10000))
 646                                         {
 647                                                 AnEXTEN |= EXT_IISPOSW; // Word outer displacement
 648                                                 AMn = MEMPOST + ea_PC;
 649                                                 if (optim_warn_flag)
 650                                                         warn("absolute value in outer displacement ranging $FFFF8000..$00007FFF optimised to absolute short");
 651                                         }
 652                                 }
 653
 654                                 // Check for final closing parenthesis
 655                                 if (*tok == ')')
 656                                 {
 657                                         tok++;
 658                                         goto AnOK;
 659                                 }
 660                                 else
 661                                         return error("Closing parenthesis missing on addressing mode");
 662
 663 IS_SUPPRESSEDn:
 664
 665                                 // Check for od
 666                                 if (*tok == ')')        // ([bd,An/PC],Xn)
 667                                 {
 668                                         // od is non existent, get out of jail free card
 669                                         AMn = MEMPOST + ea_PC;          // let's say it's ([bd,An],Xn,od) with od=0 then
 670                                         AnEXTEN |= EXT_IISNOIN; // No outer displacement
 671                                         tok++;
 672                                         goto AnOK;
 673                                 }
 674                                 else if (*tok!=',')
 675                                         return error("comma expected");
 676                                 else
 677                                         tok++;  // eat the comma
 678
 679                                 if ((*tok != CONST) && (*tok != SYMBOL))
 680                                         goto badmode;
 681
 682                                 expr(AnEXPR, &AnEXVAL, &AnEXATTR, &AnESYM);
 683
 684                                 if (CHECK_OPTS(OPT_020_DISP) && (AnEXVAL == 0))
 685                                 {
 686                                         // od=0 so optimise it out
 687                                         AMn = MEMPOST + ea_PC;           // let's say it's ([bd,An],Xn,od) with od=0 then
 688                                         AnEXTEN |= EXT_IISNOIN; // No outer displacement
 689                                         tok++;
 690                                         goto AnOK;
 691                                 }
 692
 693                                 // ([bd,An/PC],Xn,od)
 694                                 if (*tok == DOTL)
 695                                 {
 696                                         // expr.L
 697                                         tok++;
 698                                         AMn = MEMPOST + ea_PC;
 699                                         AnEXTEN |= EXT_IISNOIL; // Long outer displacement with IS suppressed
 700                                 }
 701                                 else
 702                                 {
 703                                         // expr[.W][]
 704                                         AnEXTEN |= EXT_IISNOIW; // Word outer displacement with IS suppressed
 705                                         AMn = MEMPRE + ea_PC;;
 706
 707                                         if (*tok == DOTW)
 708                                         {
 709                                                 //AnEXTEN|=EXT_IISNOIW; // Word outer displacement
 710                                                 AMn = MEMPOST + ea_PC;
 711                                                 tok++;
 712                                         }
 713                                         // Defined, absolute values from $FFFF8000..$00007FFF get
 714                                         // optimized to absolute short
 715                                         else if (CHECK_OPTS(OPT_020_DISP)
 716                                                 && ((AnEXATTR & (TDB | DEFINED)) == DEFINED)
 717                                                 && (((uint32_t)AnEXVAL + 0x8000) < 0x10000))
 718                                         {
 719                                                 //AnEXTEN|=EXT_IISNOIW; // Word outer displacement with IS suppressed
 720                                                 if (optim_warn_flag)
 721                                                         warn("outer displacement absolute value from $FFFF8000..$00007FFF optimised to absolute short");
 722                                         }
 723                                 }
 724
 725                                 // Check for final closing parenthesis
 726                                 if (*tok == ')')
 727                                 {
 728                                         tok++;
 729                                         goto AnOK;
 730                                 }
 731                                 else
 732                                         return error("Closing parenthesis missing on addressing mode");
 733                         }
 734                         else if (*tok == ',')
 735                         {
 736                                 tok++;                  // ([bd,An,Xn.size*scale],od)
 737
 738                                 // Check for Xn
 739                                 if ((*tok >= KW_A0) && (*tok <= KW_A7))
 740                                 {
 741                                         AnEXTEN |= ((*tok & 7) << 12);
 742                                         AnEXTEN |= EXT_A;
 743                                         tok++;
 744                                 }
 745                                 else if ((*tok >= KW_D0) && (*tok <= KW_D7))
 746                                 {
 747                                         AnEXTEN |= ((*tok & 7) << 12);
 748                                         AnEXTEN |= EXT_D;
 749                                         tok++;
 750                                 }
 751
 752                                 // Check for size
 753                                 // ([bd,An/PC],Xn.W/L...)
 754                                 switch ((int)*tok)
 755                                 {
 756                                 // Index reg size: <empty> | .W | .L
 757                                 case DOTW:
 758                                         tok++;
 759                                         break;
 760                                 default:
 761                                         break;
 762                                 case DOTL:
 763                                         tok++;
 764                                         AnEXTEN |= EXT_L;
 765                                         break;
 766                                 case DOTB:
 767                                 // .B not allowed here...
 768                                 goto badmode;
 769                                 }
 770
 771                                 // Check for scale
 772                                 if (*tok == '*')                                // ([bd,An/PC],Xn*...)
 773                                 {                                                               // scale: *1, *2, *4, *8
 774                                         tok++;
 775
 776                                         if (*tok == SYMBOL)
 777                                         {
 778                                                 if (expr(scaleexpr, &scaleval, &scaleattr, &scaleesym) != OK)
 779                                                         return error("scale factor expression must evaluate");
 780
 781                                                 switch (scaleval)
 782                                                 {
 783                                                 case 1:
 784                                                         break;
 785                                                 case 2:
 786                                                         AnIXSIZ |= TIMES2;
 787                                                         break;
 788                                                 case 4:
 789                                                         AnIXSIZ |= TIMES4;
 790                                                         break;
 791                                                 case 8:
 792                                                         AnIXSIZ |= TIMES8;
 793                                                         break;
 794                                                 default:
 795                                                         goto badmode;
 796                                                 }
 797                                         }
 798                                         else if (*tok++ != CONST)
 799                                                 goto badmode;
 800                                         else
 801                                         {
 802                                                 switch ((int)*tok++)
 803                                                 {
 804                                                 case 1:
 805                                                         break;
 806                                                 case 2:
 807                                                         AnIXSIZ |= TIMES2;
 808                                                         AnEXTEN |= 1 << 9;
 809                                                         break;
 810                                                 case 4:
 811                                                         AnIXSIZ |= TIMES4;
 812                                                         AnEXTEN |= 2 << 9;
 813                                                         break;
 814                                                 case 8:
 815                                                         AnIXSIZ |= TIMES8;
 816                                                         AnEXTEN |= 3 << 9;
 817                                                         break;
 818                                                 default:
 819                                                         goto badmode;
 820                                                 }
 821
 822                                                 tok++;  // Take into account that constants are 64-bit
 823                                         }
 824                                 }
 825
 826                                 // Check for ]
 827                                 if (*tok != ']')
 828                                         return error("Expected closing bracket ]");
 829                                 tok++;                  // Eat the bracket
 830
 831                                 // Check for od
 832                                 if (*tok == ')')        // ([bd,An/PC,Xn]...
 833                                 {
 834                                         // od is non existent, get out of jail free card
 835                                         AMn = MEMPRE + ea_PC;                   // let's say it's ([bd,An,Xn],od) with od suppressed then
 836                                         AnEXTEN |= EXT_IISPREN; // No outer displacement
 837                                         tok++;
 838                                         goto AnOK;
 839                                 }
 840                                 else if (*tok++ != ',')
 841                                         return error("comma expected after ]");
 842
 843                                 if (*tok == SYMBOL || *tok == CONST)
 844                                 {
 845                                         if (expr(AnEXPR, &AnEXVAL, &AnEXATTR, &AnESYM) != OK)
 846                                                 goto badmode;
 847
 848                                         if (CHECK_OPTS(OPT_020_DISP) && (AnEXVAL == 0) && (AnEXATTR & DEFINED))
 849                                         {
 850                                                 // od=0 so optimise it out
 851                                                 AMn = MEMPRE + ea_PC;            // let's say it's ([bd,An],Xn,od) with od=0 then
 852                                                 AnEXTEN |= EXT_IISPRE0; // No outer displacement
 853                                                 tok++;
 854                                                 goto AnOK;
 855                                         }
 856                                 }
 857
 858                                 // ([bd,An/PC,Xn],od)
 859                                 if (*tok == DOTL)
 860                                 {
 861                                         // expr.L
 862                                         AMn = MEMPRE + ea_PC;
 863                                         tok++;
 864                                         AnEXTEN |= EXT_IISPREL;
 865                                 }
 866                                 else
 867                                 {
 868                                         // expr.[W]
 869                                         AMn = MEMPRE + ea_PC;
 870                                         int expr_size = EXT_IISPREW; // Assume we have a .w value
 871
 872                                         if ((AnEXVAL + 0x8000) > 0x10000)
 873                                         {
 874                                                 // Long value, so mark it as such for now
 875                                                 expr_size = EXT_IISPREL;
 876
 877                                                 // Defined, absolute values from $FFFF8000..$00007FFF
 878                                                 // get optimized to absolute short
 879                                                 if (CHECK_OPTS(OPT_020_DISP)
 880                                                         && ((AnEXATTR & (TDB | DEFINED)) == DEFINED)
 881                                                         && (((uint32_t)AnEXVAL + 0x8000) < 0x10000))
 882                                                 {
 883                                                         expr_size = EXT_IISPREW;
 884
 885                                                         if (optim_warn_flag)
 886                                                                 warn("outer displacement absolute value from $FFFF8000..$00007FFF optimised to absolute short");
 887                                                 }
 888                                         }
 889
 890                                         AnEXTEN |= expr_size; // Assume we have a .w value
 891
 892                                         // Is .W forced here?
 893                                         if (*tok == DOTW)
 894                                         {
 895                                                 tok++;
 896
 897                                                 if (expr_size == EXT_IISPREL)
 898                                                         return error("outer displacement value does not fit in .w size");
 899                                         }
 900                                 }
 901
 902                                 // Check for final closing parenthesis
 903                                 if (*tok == ')')
 904                                 {
 905                                         tok++;
 906                                         goto AnOK;
 907                                 }
 908                                 else
 909                                         return error("Closing parenthesis missing on addressing mode");
 910                         }
 911                         else
 912                                 goto badmode;
 913                 }
 914                 else
 915                 {
 916                         // (expr...
 917                         if (expr(AnEXPR, &AnEXVAL, &AnEXATTR, &AnESYM) != OK)
 918                                 return ERROR;
 919
 920                         // It could be that this is really just an expression prefixing a
 921                         // register as a displacement...
 922                         if (*tok == ')')
 923                         {
 924                                 tok++;
 925                                 goto CHK_FOR_DISPn;
 926                         }
 927
 928                         // Otherwise, check for PC & etc displacements...
 929                         if (*tok++ != ',')
 930                                 goto badmode;
 931
 932                         if ((*tok >= KW_A0) && (*tok <= KW_A7))
 933                         {
 934                                 AnREG = *tok & 7;
 935                                 tok++;
 936
 937                                 if (*tok == ',')
 938                                 {
 939                                         // Check if we're actually doing d8(An,Dn) or
 940                                         // (d16,An,Dn[.size][*scale])
 941                                         // TODO: not a very clear cut case from what I can think.
 942                                         // The only way to distinguish between the two is to check
 943                                         // AnEXVAL and see if it's >127 or <-128. But this doesn't
 944                                         // work if AnEXVAL isn't defined yet. For now we fall
 945                                         // through to d8(An,Dn) but this might bite us in the arse
 946                                         // during fixups...
 947                                         if ((AnEXATTR & DEFINED) && (AnEXVAL + 0x80 > 0x100))
 948                                         {
 949                                                 // We're going to treat it as a full extension format
 950                                                 // with no indirect access and no base displacement/
 951                                                 // index register suppression
 952                                                 AnEXTEN |= EXT_FULLWORD;        // Definitely using full extension format, so set bit 8
 953                                                 AnEXTEN |= EXT_IISPRE0;         // No Memory Indirect Action
 954                                                 AnEXTEN |= EXT_BDSIZEL;         // Base Displacement Size Long
 955                                                 tok++;                                          // Get past the comma
 956
 957                                                 // Our expression is techically a base displacement,
 958                                                 // so let's copy it to the relevant variables so
 959                                                 // eagen0.c can pick it up properly
 960                                                 AnBEXVAL = AnEXVAL;
 961                                                 AnBEXATTR = AnEXATTR;
 962
 963                                                 if ((*tok >= KW_D0) && (*tok <= KW_D7))
 964                                                 {
 965                                                         AnEXTEN |= ((*tok++) & 7) << 12;
 966                                                         // Check for size
 967                                                         {
 968                                                                 switch ((int)*tok)
 969                                                                 {
 970                                                                 // Index reg size: <empty> | .W | .L
 971                                                                 case DOTW:
 972                                                                         tok++;
 973                                                                         break;
 974                                                                 default:
 975                                                                         break;
 976                                                                 case DOTL:
 977                                                                         tok++;
 978                                                                         AnEXTEN |= EXT_L;
 979                                                                         break;
 980                                                                 case DOTB:
 981                                                                         // .B not allowed here...
 982                                                                         goto badmode;
 983                                                                 }
 984                                                         }
 985                                                         // Check for scale
 986                                                         if (*tok == '*')                // (d16,An,Dn[.size][*scale])
 987                                                         {                                               // scale: *1, *2, *4, *8
 988                                                                 tok++;
 989
 990                                                                 if (*tok == SYMBOL)
 991                                                                 {
 992                                                                         if (expr(scaleexpr, &scaleval, &scaleattr, &scaleesym) != OK)
 993                                                                                 return error("scale factor expression must evaluate");
 994
 995                                                                         switch (scaleval)
 996                                                                         {
 997                                                                         case 1:
 998                                                                                 break;
 999                                                                         case 2:
1000                                                                                 AnIXSIZ |= TIMES2;
1001                                                                                 break;
1002                                                                         case 4:
1003                                                                                 AnIXSIZ |= TIMES4;
1004                                                                                 break;
1005                                                                         case 8:
1006                                                                                 AnIXSIZ |= TIMES8;
1007                                                                                 break;
1008                                                                         default:
1009                                                                                 goto badmode;
1010                                                                         }
1011                                                                 }
1012                                                                 else if (*tok++ != CONST)
1013                                                                         goto badmode;
1014                                                                 else
1015                                                                 {
1016                                                                         switch ((int)*tok++)
1017                                                                         {
1018                                                                         case 1:
1019                                                                                 break;
1020                                                                         case 2:
1021                                                                                 AnIXSIZ |= TIMES2;
1022                                                                                 break;
1023                                                                         case 4:
1024                                                                                 AnIXSIZ |= TIMES4;
1025                                                                                 break;
1026                                                                         case 8:
1027                                                                                 AnIXSIZ |= TIMES8;
1028                                                                                 break;
1029                                                                         default:
1030                                                                                 goto badmode;
1031                                                                         }
1032
1033                                                                         tok++;  // Take into account that constants are 64-bit
1034                                                                 }
1035                                                         }
1036
1037                                                         if (*tok++ != ')')
1038                                                                 return error("Closing parenthesis missing on addressing mode");
1039
1040                                                         // Let's say that this is the closest to our case
1041                                                         AMn = MEMPOST;
1042                                                         goto AnOK;
1043                                                 }
1044                                                 else
1045                                                         goto badmode;
1046                                         }
1047
1048                                         AMn = AINDEXED;
1049                                         goto AMn_IXN;
1050                                 }
1051                                 else if (*tok == ')')
1052                                 {
1053                                         AMn = ADISP;
1054                                         tok++;
1055                                         goto AnOK;
1056                                 }
1057                                 else
1058                                         goto badmode;
1059                         }
1060                         else if (*tok == KW_PC)
1061                         {
1062                                 if (*++tok == ',')
1063                                 {                             // expr(PC,Xn...)
1064                                         AMn = PCINDEXED;
1065                                         goto AMn_IXN;
1066                                 }
1067                                 else if (*tok == ')')
1068                                 {
1069                                         AMn = PCDISP;             // expr(PC)
1070                                         tok++;
1071                                         goto AnOK;
1072                                 }
1073                                 else
1074                                         goto badmode;
1075                         }
1076                         else
1077                                 goto badmode;
1078                 }
1079         }
1080         else if (*tok == '-' && tok[1] == '(' && ((tok[2] >= KW_A0) && (tok[2] <= KW_A7)) && tok[3] == ')')
1081         {
1082                 AMn = APREDEC;
1083                 AnREG = tok[2] & 7;
1084                 tok += 4;
1085         }
1086         else if (*tok == KW_CCR)
1087         {
1088                 AMn = AM_CCR;
1089                 tok++;
1090                 goto AnOK;
1091         }
1092         else if (*tok == KW_SR)
1093         {
1094                 AMn = AM_SR;
1095                 tok++;
1096                 goto AnOK;
1097         }
1098         else if (*tok == KW_USP)
1099         {
1100                 AMn = AM_USP;
1101                 tok++;
1102                 AnREG = 2;      // Added this for the case of USP used in movec (see CREGlut in mach.c). Hopefully nothing gets broken!
1103                 goto AnOK;
1104         }
1105         else if ((*tok >= KW_IC40) && (*tok <= KW_BC40))
1106         {
1107                 AMn = CACHES;
1108                 AnREG = *tok++ - KW_IC40;
1109
1110                 // After a cache keyword only a comma or EOL is allowed
1111                 if ((*tok != ',') && (*tok != EOL))
1112                         return ERROR;
1113                 goto AnOK;
1114         }
1115         else if ((*tok >= KW_SFC) && (*tok <= KW_CRP))
1116         {
1117                 AMn = CREG;
1118                 AnREG = (*tok++) - KW_SFC;
1119                 goto AnOK;
1120         }
1121         else if ((*tok >= KW_FP0) && (*tok <= KW_FP7))
1122         {
1123                 AMn = FREG;
1124                 AnREG = (*tok++ & 7);
1125         }
1126         else if ((*tok >= KW_FPIAR) && (*tok <= KW_FPCR))
1127         {
1128                 AMn = FPSCR;
1129                 AnREG = (1 << ((*tok++) - KW_FPIAR + 10));
1130         }
1131         // expr
1132         // expr.w
1133         // expr.l
1134         // d16(An)
1135         // d8(An,Xn[.siz])
1136         // d16(PC)
1137         // d8(PC,Xn[.siz])
1138         else
1139         {
1140                 if (expr(AnEXPR, &AnEXVAL, &AnEXATTR, &AnESYM) != OK)
1141                         return ERROR;
1142
1143 CHK_FOR_DISPn:
1144                 if (*tok == DOTW)
1145                 {
1146                         // expr.W
1147                         tok++;
1148                         AMn = ABSW;
1149
1150                         if (((AnEXATTR & (TDB | DEFINED)) == DEFINED) && (AnEXVAL < 0x10000))
1151                                 AnEXVAL = (int32_t)(int16_t)AnEXVAL;  // Sign extend value
1152
1153                         goto AnOK;
1154                 }
1155                 else if (*tok != '(')
1156                 {
1157                         // expr[.L]
1158                         AMn = ABSL;
1159
1160                         // When PC relative is enforced, check for any symbols that aren't
1161                         // EQU'd, in this case it's an illegal mode
1162                         if ((CHECK_OPTS(OPT_PC_RELATIVE)) && (AnEXATTR & REFERENCED) && (AnEXATTR & DEFINED) && (!(AnEXATTR & EQUATED)))
1163                                 return error("relocation not allowed");
1164
1165                         // .L is forced here
1166                         if (*tok == DOTL)
1167                         {
1168                                 tok++;
1169                                 AMn = ABSL;
1170                         }
1171                         else
1172                         {
1173                                 // Defined, absolute values from $FFFF8000..$00007FFF get
1174                                 // optimized to absolute short
1175                                 if (CHECK_OPTS(OPT_ABS_SHORT)
1176                                         && ((AnEXATTR & (TDB | DEFINED)) == DEFINED)
1177                                         && (((uint32_t)AnEXVAL + 0x8000) < 0x10000))
1178                                 {
1179                                         AMn = ABSW;
1180
1181                                         if (optim_warn_flag)
1182                                                 warn("absolute value from $FFFF8000..$00007FFF optimised to absolute short");
1183                                 }
1184                         }
1185
1186                         goto AnOK;
1187                 }
1188
1189                 tok++;
1190
1191                 if ((*tok >= KW_A0) && (*tok <= KW_A7))
1192                 {
1193                         AnREG = *tok++ & 7;
1194
1195                         if (*tok == ')')
1196                         {
1197                                 AMn = ADISP;
1198                                 tok++;
1199                                 goto AnOK;
1200                         }
1201
1202                         AMn = AINDEXED;
1203                         goto AMn_IXN;
1204                 }
1205                 else if (*tok == KW_PC)
1206                 {
1207                         if (*++tok == ')')
1208                         {
1209                                 AMn = PCDISP;
1210                                 tok++;
1211                                 goto AnOK;
1212                         }
1213
1214                         AMn = PCINDEXED;
1215                         goto AMn_IXN;
1216                 }
1217
1218                 goto badmode;
1219         }
1220
1221         // Addressing mode OK
1222 AnOK:
1223         ;
1224 }
1225
1226 // Clean up dirty little macros
1227 #undef AnOK
1228 #undef AMn
1229 #undef AnREG
1230 #undef AnIXREG
1231 #undef AnIXSIZ
1232 #undef AnEXPR
1233 #undef AnEXVAL
1234 #undef AnEXATTR
1235 #undef AnOEXPR
1236 #undef AnOEXVAL
1237 #undef AnOEXATTR
1238 #undef AnESYM
1239 #undef AMn_IX0
1240 #undef AMn_IXN
1241 #undef CHK_FOR_DISPn
1242 #undef AnBEXPR
1243 #undef AnBEXVAL
1244 #undef AnBEXATTR
1245 #undef AnBZISE
1246 #undef AnEXTEN
1247 #undef AMn_030
1248 #undef IS_SUPPRESSEDn
1249 #undef CHECKODn