Shamusworld >> Repos - rmac/blob - riscasm.c

   1 //
   2 // RMAC - Reboot's Macro Assembler for the Atari Jaguar Console System
   3 // RISCA.C - GPU/DSP Assembler
   4 // Copyright (C) 199x Landon Dyer, 2011 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 #include "riscasm.h"
  10 #include "error.h"
  11 #include "sect.h"
  12 #include "token.h"
  13 #include "expr.h"
  14 #include "direct.h"
  15 #include "mark.h"
  16 #include "amode.h"
  17
  18 #define DEF_MR                          // Declare keyword values
  19 #include "risckw.h"                     // Incl. generated risc keywords
  20
  21 #define DEF_KW                          // Declare keyword values
  22 #include "kwtab.h"                      // Incl. generated keyword tables & defs
  23
  24
  25 unsigned altbankok = 0;         // Ok to use alternate register bank
  26 unsigned orgactive = 0;         // RISC org directive active
  27 unsigned orgaddr = 0;           // Org'd address
  28 unsigned orgwarning = 0;        // Has an ORG warning been issued
  29 int lastOpcode = -1;            // Last RISC opcode assembled
  30
  31 const char reg_err[] = "missing register R0...R31";
  32
  33 // Jaguar Jump Condition Names
  34 const char condname[MAXINTERNCC][5] = {
  35         "NZ", "Z", "NC", "NCNZ", "NCZ", "C", "CNZ", "CZ", "NN", "NNNZ", "NNZ",
  36         "N", "N_NZ", "N_Z", "T", "A", "NE", "EQ", "CC", "HS", "HI", "CS", "LO",
  37         "PL", "MI", "F"
  38 };
  39
  40 // Jaguar Jump Condition Numbers
  41 const char condnumber[] = {
  42         1, 2, 4, 5, 6, 8, 9, 10, 20, 21, 22, 24, 25, 26,
  43         0, 0, 1, 2, 4, 4, 5,  8,  8, 20, 24, 31
  44 };
  45
  46 const struct opcoderecord roptbl[] = {
  47         { MR_ADD,     RI_TWO,    0 },
  48         { MR_ADDC,    RI_TWO,    1 },
  49         { MR_ADDQ,    RI_NUM_32, 2 },
  50         { MR_ADDQT,   RI_NUM_32, 3 },
  51         { MR_SUB,     RI_TWO,    4 },
  52         { MR_SUBC,    RI_TWO,    5 },
  53         { MR_SUBQ,    RI_NUM_32, 6 },
  54         { MR_SUBQT,   RI_NUM_32, 7 },
  55         { MR_NEG,     RI_ONE,    8 },
  56         { MR_AND,     RI_TWO,    9 },
  57         { MR_OR,      RI_TWO,    10 },
  58         { MR_XOR,     RI_TWO,    11 },
  59         { MR_NOT,     RI_ONE,    12 },
  60         { MR_BTST,    RI_NUM_31, 13 },
  61         { MR_BSET,    RI_NUM_31, 14 },
  62         { MR_BCLR,    RI_NUM_31, 15 },
  63         { MR_MULT,    RI_TWO,    16 },
  64         { MR_IMULT,   RI_TWO,    17 },
  65         { MR_IMULTN,  RI_TWO,    18 },
  66         { MR_RESMAC,  RI_ONE,    19 },
  67         { MR_IMACN,   RI_TWO,    20 },
  68         { MR_DIV,     RI_TWO,    21 },
  69         { MR_ABS,     RI_ONE,    22 },
  70         { MR_SH,      RI_TWO,    23 },
  71         { MR_SHLQ,    RI_NUM_32, 24 + SUB32 },
  72         { MR_SHRQ,    RI_NUM_32, 25 },
  73         { MR_SHA,     RI_TWO,    26 },
  74         { MR_SHARQ,   RI_NUM_32, 27 },
  75         { MR_ROR,     RI_TWO,    28 },
  76         { MR_RORQ,    RI_NUM_32, 29 },
  77         { MR_ROLQ,    RI_NUM_32, 29 + SUB32 },
  78         { MR_CMP,     RI_TWO,    30 },
  79         { MR_CMPQ,    RI_NUM_15, 31 },
  80         { MR_SAT8,    RI_ONE,    32 + GPUONLY },
  81         { MR_SUBQMOD, RI_NUM_32, 32 + DSPONLY },
  82         { MR_SAT16,   RI_ONE,    33 + GPUONLY },
  83         { MR_SAT16S,  RI_ONE,    33 + DSPONLY },
  84         { MR_MOVEQ,   RI_NUM_31, 35 },
  85         { MR_MOVETA,  RI_TWO,    36 },
  86         { MR_MOVEFA,  RI_TWO,    37 },
  87         { MR_MOVEI,   RI_MOVEI,  38 },
  88         { MR_LOADB,   RI_LOADN,  39 },
  89         { MR_LOADW,   RI_LOADN,  40 },
  90         { MR_LOADP,   RI_LOADN,  42 + GPUONLY },
  91         { MR_SAT32S,  RI_ONE,    42 + DSPONLY },
  92         { MR_STOREB,  RI_STOREN, 45 },
  93         { MR_STOREW,  RI_STOREN, 46 },
  94         { MR_STOREP,  RI_STOREN, 48 + GPUONLY },
  95         { MR_MIRROR,  RI_ONE,    48 + DSPONLY },
  96         { MR_JUMP,    RI_JUMP,   52 },
  97         { MR_JR,      RI_JR,     53 },
  98         { MR_MMULT,   RI_TWO,    54 },
  99         { MR_MTOI,    RI_TWO,    55 },
 100         { MR_NORMI,   RI_TWO,    56 },
 101         { MR_NOP,     RI_NONE,   57 },
 102         { MR_SAT24,   RI_ONE,    62 },
 103         { MR_UNPACK,  RI_ONE,    63 + GPUONLY },
 104         { MR_PACK,    RI_ONE,    63 + GPUONLY },
 105         { MR_ADDQMOD, RI_NUM_32, 63 + DSPONLY },
 106         { MR_MOVE,    RI_MOVE,   0 },
 107         { MR_LOAD,    RI_LOAD,   0 },
 108         { MR_STORE,   RI_STORE,  0 }
 109 };
 110
 111
 112 //
 113 // Convert a string to uppercase
 114 //
 115 void strtoupper(char * s)
 116 {
 117         while (*s)
 118                 *s++ &= 0xDF;
 119 }
 120
 121
 122 //
 123 // Function to return "malformed expression" error
 124 // This is done mainly to remove a bunch of GOTO statements in the parser
 125 //
 126 static inline int MalformedOpcode(int signal)
 127 {
 128         char buf[16];
 129         sprintf(buf, "%02X", signal);
 130         return errors("Malformed opcode [internal $%s]", buf);
 131 }
 132
 133
 134 //
 135 // Build RISC instruction word
 136 //
 137 void BuildRISCIntructionWord(unsigned short opcode, int reg1, int reg2)
 138 {
 139         // Check for absolute address setting
 140         if (!orgwarning && !orgactive)
 141         {
 142 //              warn("GPU/DSP code outside of absolute section");
 143                 warn("RISC code generated with no origin defined");
 144                 orgwarning = 1;
 145         }
 146
 147         int value = ((opcode & 0x3F) << 10) + ((reg1 & 0x1F) << 5) + (reg2 & 0x1F);
 148         D_word(value);
 149 }
 150
 151
 152 //
 153 // Get a RISC register
 154 //
 155 int GetRegister(WORD rattr)
 156 {
 157         VALUE eval;                                     // Expression value
 158         WORD eattr;                                     // Expression attributes
 159         SYM * esym;                                     // External symbol involved in expr.
 160         TOKEN r_expr[EXPRSIZE];         // Expression token list
 161
 162         // Evaluate what's in the global "tok" buffer
 163         if (expr(r_expr, &eval, &eattr, &esym) != OK)
 164                 return ERROR;
 165
 166         if ((challoc - ch_size) < 4)
 167                 chcheck(4L);
 168
 169         if (!(eattr & DEFINED))
 170         {
 171                 AddFixup((WORD)(FU_WORD | rattr), sloc, r_expr);
 172                 return 0;
 173         }
 174
 175         // If we got a register in range (0-31), return it
 176         if ((eval >= 0) && (eval <= 31))
 177                 return eval;
 178
 179         // Otherwise, it's out of range & we flag an error
 180         return error(reg_err);
 181 }
 182
 183
 184 //
 185 // Do RISC code generation
 186 //
 187 int GenerateRISCCode(int state)
 188 {
 189         int reg1;                                       // Register 1
 190         int reg2;                                       // Register 2
 191         int val = 0;                            // Constructed value
 192         char scratch[80];
 193         SYM * ccsym;
 194         SYM * sy;
 195         int i, commaFound;
 196         TOKEN * t;
 197         WORD attrflg;
 198         int indexed;                            // Indexed register flag
 199
 200         VALUE eval;                                     // Expression value
 201         WORD eattr;                                     // Expression attributes
 202         SYM * esym;                                     // External symbol involved in expr.
 203         TOKEN r_expr[EXPRSIZE];         // Expression token list
 204
 205         // Get opcode parameter and type
 206         unsigned short parm = (WORD)(roptbl[state - 3000].parm);
 207         unsigned type = roptbl[state - 3000].typ;
 208
 209         // Detect whether the opcode parmeter passed determines that the opcode is
 210         // specific to only one of the RISC processors and ensure it is legal in
 211         // the current code section. If not then show error and return.
 212         if (((parm & GPUONLY) && rdsp) || ((parm & DSPONLY) && rgpu))
 213                 return error("Opcode is not valid in this code section");
 214
 215         // Process RISC opcode
 216         switch (type)
 217         {
 218         // No operand instructions
 219         // NOP (57)
 220         case RI_NONE:
 221                 BuildRISCIntructionWord(parm, 0, 0);
 222                 break;
 223
 224         // Single operand instructions (Rd)
 225         // ABS, MIRROR, NEG, NOT, PACK, RESMAC, SAT8, SAT16, SAT16S, SAT24, SAT32S, UNPACK
 226         case RI_ONE:
 227                 reg2 = GetRegister(FU_REGTWO);
 228                 at_eol();
 229                 BuildRISCIntructionWord(parm, parm >> 6, reg2);
 230                 break;
 231
 232         // Two operand instructions (Rs,Rd)
 233         // ADD, ADDC, AND, CMP, DIV, IMACN, IMULT, IMULTN, MOVEFA, MOVETA, MULT, MMULT,
 234         // MTOI, NORMI, OR, ROR, SH, SHA, SUB, SUBC, XOR
 235         case RI_TWO:
 236                 if (parm == 37)
 237                         altbankok = 1;                      // MOVEFA
 238
 239                 reg1 = GetRegister(FU_REGONE);
 240                 CHECK_COMMA;
 241
 242                 if (parm == 36)
 243                         altbankok = 1;                      // MOVETA
 244
 245                 reg2 = GetRegister(FU_REGTWO);
 246                 at_eol();
 247                 BuildRISCIntructionWord(parm, reg1, reg2);
 248                 break;
 249
 250         // Numeric operand (n,Rd) where n = -16..+15
 251         // CMPQ
 252         case RI_NUM_15:
 253
 254         // Numeric operand (n,Rd) where n = 0..31
 255         // BCLR, BSET, BTST, MOVEQ
 256         case RI_NUM_31:
 257
 258         // Numeric operand (n,Rd) where n = 1..32
 259         // ADDQ, ADDQMOD, ADDQT, SHARQ, SHLQ, SHRQ, SUBQ, SUBQMOD, SUBQT, ROLQ, RORQ
 260         case RI_NUM_32:
 261                 switch (type)
 262                 {
 263                 case RI_NUM_15:
 264                         reg1 = -16; reg2 = 15; attrflg = FU_NUM15;
 265                         break;
 266                 default:
 267                 case RI_NUM_31:
 268                         reg1 =   0; reg2 = 31; attrflg = FU_NUM31;
 269                         break;
 270                 case RI_NUM_32:
 271                         reg1 =   1; reg2 = 32; attrflg = FU_NUM32;
 272                         break;
 273                 }
 274
 275                 if (parm & SUB32)
 276                         attrflg |= FU_SUB32;
 277
 278                 if (*tok != '#')
 279                         return MalformedOpcode(0x01);
 280
 281                 tok++;
 282
 283                 if (expr(r_expr, &eval, &eattr, &esym) != OK)
 284                         return MalformedOpcode(0x02);
 285
 286                 if ((challoc - ch_size) < 4)
 287                         chcheck(4L);
 288
 289                 if (!(eattr & DEFINED))
 290                 {
 291                         AddFixup((WORD)(FU_WORD | attrflg), sloc, r_expr);
 292                         reg1 = 0;
 293                 }
 294                 else
 295                 {
 296                         if ((int)eval < reg1 || (int)eval > reg2)
 297                                 return error("constant out of range");
 298
 299                         if (parm & SUB32)
 300                                 reg1 = 32 - eval;
 301                         else if (type == RI_NUM_32)
 302                                 reg1 = (reg1 == 32 ? 0 : eval);
 303                         else
 304                                 reg1 = eval;
 305                 }
 306
 307                 CHECK_COMMA;
 308                 reg2 = GetRegister(FU_REGTWO);
 309                 at_eol();
 310                 BuildRISCIntructionWord(parm, reg1, reg2);
 311                 break;
 312
 313         // Move Immediate--n,Rn--n in Second Word
 314         case RI_MOVEI:
 315                 if (*tok != '#')
 316                         return MalformedOpcode(0x03);
 317
 318                 tok++;
 319
 320                 if (expr(r_expr, &eval, &eattr, &esym) != OK)
 321                         return MalformedOpcode(0x04);
 322
 323                 if (lastOpcode == RI_JUMP || lastOpcode == RI_JR)
 324                 {
 325                         if (legacy_flag)
 326                         {
 327                                 // User doesn't care, emit a NOP to fix
 328                                 BuildRISCIntructionWord(57, 0, 0);
 329                                 warn("MOVEI following JUMP, inserting NOP to fix your BROKEN CODE");
 330                         }
 331                         else
 332                                 warn("MOVEI immediately follows JUMP");
 333                 }
 334
 335                 if ((challoc - ch_size) < 4)
 336                         chcheck(4L);
 337
 338                 if (!(eattr & DEFINED))
 339                 {
 340                         AddFixup(FU_LONG | FU_MOVEI, sloc + 2, r_expr);
 341                         eval = 0;
 342                 }
 343                 else
 344                 {
 345                         if (eattr & TDB)
 346 //{
 347 //printf("risca: Doing rmark for RI_MOVEI (tdb=$%X)...\n", eattr & TDB);
 348                                 rmark(cursect, sloc + 2, (eattr & TDB), (MLONG | MMOVEI), NULL);
 349 //}
 350                 }
 351
 352                 val = ((eval >> 16) & 0x0000FFFF) | ((eval << 16) & 0xFFFF0000);
 353                 CHECK_COMMA;
 354                 reg2 = GetRegister(FU_REGTWO);
 355                 at_eol();
 356                 D_word((((parm & 0x3F) << 10) + reg2));
 357                 D_long(val);
 358                 break;
 359
 360         // PC,Rd or Rs,Rd
 361         case RI_MOVE:
 362                 if (*tok == KW_PC)
 363                 {
 364                         parm = 51;
 365                         reg1 = 0;
 366                         tok++;
 367                 }
 368                 else
 369                 {
 370                         parm = 34;
 371                         reg1 = GetRegister(FU_REGONE);
 372                 }
 373
 374                 CHECK_COMMA;
 375                 reg2 = GetRegister(FU_REGTWO);
 376                 at_eol();
 377                 BuildRISCIntructionWord(parm, reg1, reg2);
 378                 break;
 379
 380         // (Rn),Rn = 41 / (R14/R15+n),Rn = 43/44 / (R14/R15+Rn),Rn = 58/59
 381         case RI_LOAD:
 382                 indexed = 0;
 383                 parm = 41;
 384
 385                 if (*tok != '(')
 386                         return MalformedOpcode(0x05);
 387
 388                 tok++;
 389
 390                 if ((*tok == KW_R14 || *tok == KW_R15) && (*(tok + 1) != ')'))
 391                         indexed = (*tok - KW_R0);
 392
 393                 if (*tok == SYMBOL)
 394                 {
 395 //                      sy = lookup((char *)tok[1], LABEL, 0);
 396                         sy = lookup(string[tok[1]], LABEL, 0);
 397
 398                         if (!sy)
 399                         {
 400                                 error(reg_err);
 401                                 return ERROR;
 402                         }
 403
 404                         if (sy->sattre & EQUATEDREG)
 405                         {
 406                                 if (((sy->svalue & 0x1F) == 14 || (sy->svalue & 0x1F) == 15)
 407                                         && (*(tok + 2) != ')'))
 408                                 {
 409                                         indexed = (sy->svalue & 0x1F);
 410                                         tok++;
 411                                 }
 412                         }
 413                 }
 414
 415                 if (!indexed)
 416                 {
 417                         reg1 = GetRegister(FU_REGONE);
 418                 }
 419                 else
 420                 {
 421                         reg1 = indexed;
 422                         indexed = 0;
 423                         tok++;
 424
 425                         if (*tok == '+')
 426                         {
 427                                 parm = (WORD)(reg1 - 14 + 58);
 428                                 tok++;
 429
 430                                 if (*tok >= KW_R0 && *tok <= KW_R31)
 431                                         indexed = 1;
 432
 433                                 if (*tok == SYMBOL)
 434                                 {
 435 //                                      sy = lookup((char *)tok[1], LABEL, 0);
 436                                         sy = lookup(string[tok[1]], LABEL, 0);
 437
 438                                         if (!sy)
 439                                         {
 440                                                 error(reg_err);
 441                                                 return ERROR;
 442                                         }
 443
 444                                         if (sy->sattre & EQUATEDREG)
 445                                                 indexed = 1;
 446                                 }
 447
 448                                 if (indexed)
 449                                 {
 450                                         reg1 = GetRegister(FU_REGONE);
 451                                 }
 452                                 else
 453                                 {
 454                                         if (expr(r_expr, &eval, &eattr, &esym) != OK)
 455                                                 return MalformedOpcode(0x06);
 456
 457                                         if ((challoc - ch_size) < 4)
 458                                                 chcheck(4L);
 459
 460                                         if (!(eattr & DEFINED))
 461                                                 return error("constant expected after '+'");
 462
 463                                         reg1 = eval;
 464
 465                                         if (reg1 == 0)
 466                                         {
 467                                                 reg1 = 14 + (parm - 58);
 468                                                 parm = 41;
 469                                                 warn("NULL offset in LOAD ignored");
 470                                         }
 471                                         else
 472                                         {
 473                                                 if (reg1 < 1 || reg1 > 32)
 474                                                         return error("constant in LOAD out of range");
 475
 476                                                 if (reg1 == 32)
 477                                                         reg1 = 0;
 478
 479                                                 parm = (WORD)(parm - 58 + 43);
 480                                         }
 481                                 }
 482                         }
 483                         else
 484                         {
 485                                 reg1 = GetRegister(FU_REGONE);
 486                         }
 487                 }
 488
 489                 if (*tok != ')')
 490                         return MalformedOpcode(0x07);
 491
 492                 tok++;
 493                 CHECK_COMMA;
 494                 reg2 = GetRegister(FU_REGTWO);
 495                 at_eol();
 496                 BuildRISCIntructionWord(parm, reg1, reg2);
 497                 break;
 498
 499         // Rn,(Rn) = 47 / Rn,(R14/R15+n) = 49/50 / Rn,(R14/R15+Rn) = 60/61
 500         case RI_STORE:
 501                 parm = 47;
 502                 reg1 = GetRegister(FU_REGONE);
 503                 CHECK_COMMA;
 504
 505                 if (*tok != '(')
 506                         return MalformedOpcode(0x08);
 507
 508                 tok++;
 509                 indexed = 0;
 510
 511                 if ((*tok == KW_R14 || *tok == KW_R15) && (*(tok + 1) != ')'))
 512                         indexed = (*tok - KW_R0);
 513
 514                 if (*tok == SYMBOL)
 515                 {
 516                         sy = lookup(string[tok[1]], LABEL, 0);
 517
 518                         if (!sy)
 519                         {
 520                                 error(reg_err);
 521                                 return ERROR;
 522                         }
 523
 524                         if (sy->sattre & EQUATEDREG)
 525                         {
 526                                 if (((sy->svalue & 0x1F) == 14 || (sy->svalue & 0x1F) == 15)
 527                                         && (*(tok + 2) != ')'))
 528                                 {
 529                                         indexed = (sy->svalue & 0x1F);
 530                                         tok++;
 531                                 }
 532                         }
 533                 }
 534
 535                 if (!indexed)
 536                 {
 537                         reg2 = GetRegister(FU_REGTWO);
 538                 }
 539                 else
 540                 {
 541                         reg2 = indexed;
 542                         indexed = 0;
 543                         tok++;
 544
 545                         if (*tok == '+')
 546                         {
 547                                 parm = (WORD)(reg2 - 14 + 60);
 548                                 tok++;
 549
 550                                 if (*tok >= KW_R0 && *tok <= KW_R31)
 551                                         indexed = 1;
 552
 553                                 if (*tok == SYMBOL)
 554                                 {
 555                                         sy = lookup(string[tok[1]], LABEL, 0);
 556
 557                                         if (!sy)
 558                                         {
 559                                                 error(reg_err);
 560                                                 return ERROR;
 561                                         }
 562
 563                                         if (sy->sattre & EQUATEDREG)
 564                                                 indexed = 1;
 565                                 }
 566
 567                                 if (indexed)
 568                                 {
 569                                         reg2 = GetRegister(FU_REGTWO);
 570                                 }
 571                                 else
 572                                 {
 573                                         if (expr(r_expr, &eval, &eattr, &esym) != OK)
 574                                                 return MalformedOpcode(0x09);
 575
 576                                         if ((challoc - ch_size) < 4)
 577                                                 chcheck(4L);
 578
 579                                         if (!(eattr & DEFINED))
 580                                         {
 581                                                 AddFixup(FU_WORD | FU_REGTWO, sloc, r_expr);
 582                                                 reg2 = 0;
 583                                         }
 584                                         else
 585                                         {
 586                                                 reg2 = eval;
 587
 588                                                 if (reg2 == 0)
 589                                                 {
 590                                                         reg2 = 14 + (parm - 60);
 591                                                         parm = 47;
 592                                                         warn("NULL offset in STORE ignored");
 593                                                 }
 594                                                 else
 595                                                 {
 596                                                         if (reg2 < 1 || reg2 > 32)
 597                                                                 return error("constant in STORE out of range");
 598
 599                                                         if (reg2 == 32)
 600                                                                 reg2 = 0;
 601
 602                                                         parm = (WORD)(parm - 60 + 49);
 603                                                 }
 604                                         }
 605                                 }
 606                         }
 607                         else
 608                         {
 609                                 reg2 = GetRegister(FU_REGTWO);
 610                         }
 611                 }
 612
 613                 if (*tok != ')')
 614                         return MalformedOpcode(0x0A);
 615
 616                 tok++;
 617                 at_eol();
 618                 BuildRISCIntructionWord(parm, reg2, reg1);
 619                 break;
 620
 621         // LOADB/LOADP/LOADW (Rn),Rn
 622         case RI_LOADN:
 623                 if (*tok != '(')
 624                         return MalformedOpcode(0x0B);
 625
 626                 tok++;
 627                 reg1 = GetRegister(FU_REGONE);
 628
 629                 if (*tok != ')')
 630                         return MalformedOpcode(0x0C);
 631
 632                 tok++;
 633                 CHECK_COMMA;
 634                 reg2 = GetRegister(FU_REGTWO);
 635                 at_eol();
 636                 BuildRISCIntructionWord(parm, reg1, reg2);
 637                 break;
 638
 639         // STOREB/STOREP/STOREW Rn,(Rn)
 640         case RI_STOREN:
 641                 reg1 = GetRegister(FU_REGONE);
 642                 CHECK_COMMA;
 643
 644                 if (*tok != '(')
 645                         return MalformedOpcode(0x0D);
 646
 647                 tok++;
 648                 reg2 = GetRegister(FU_REGTWO);
 649
 650                 if (*tok != ')')
 651                         return MalformedOpcode(0x0E);
 652
 653                 tok++;
 654                 at_eol();
 655                 BuildRISCIntructionWord(parm, reg2, reg1);
 656                 break;
 657
 658         // Jump Relative - cc,n - n=-16..+15 words, reg2=cc
 659         case RI_JR:
 660
 661         // Jump Absolute - cc,(Rs) - reg2=cc
 662         case RI_JUMP:
 663                 // Check to see if there is a comma in the token string. If not then
 664                 // the JR or JUMP should default to 0, Jump Always
 665                 commaFound = 0;
 666
 667                 for(t=tok; *t!=EOL; t++)
 668                 {
 669                         if (*t == ',')
 670                         {
 671                                 commaFound = 1;
 672                                 break;
 673                         }
 674                 }
 675
 676                 if (commaFound)
 677                 {
 678                         if (*tok == CONST)
 679                         {
 680                                 // CC using a constant number
 681                                 tok++;
 682                                 val = *tok;
 683                                 tok++;
 684                                 CHECK_COMMA;
 685                         }
 686                         else if (*tok == SYMBOL)
 687                         {
 688                                 val = 99;
 689 //                              strcpy(scratch, (char *)tok[1]);
 690                                 strcpy(scratch, string[tok[1]]);
 691                                 strtoupper(scratch);
 692
 693                                 for(i=0; i<MAXINTERNCC; i++)
 694                                 {
 695                                         // Look for the condition code & break if found
 696                                         if (strcmp(condname[i], scratch) == 0)
 697                                         {
 698                                                 val = condnumber[i];
 699                                                 break;
 700                                         }
 701                                 }
 702
 703                                 // Standard CC was not found, look for an equated one
 704                                 if (val == 99)
 705                                 {
 706 //                                      ccsym = lookup((char *)tok[1], LABEL, 0);
 707                                         ccsym = lookup(string[tok[1]], LABEL, 0);
 708
 709                                         if (ccsym && (ccsym->sattre & EQUATEDCC) && !(ccsym->sattre & UNDEF_CC))
 710                                         {
 711                                                 val = ccsym->svalue;
 712                                         }
 713                                         else
 714                                                 return error("unknown condition code");
 715                                 }
 716
 717                                 tok += 2;
 718                                 CHECK_COMMA;
 719                         }
 720                         else if (*tok == '(')
 721                         {
 722                                 // Set CC to "Jump Always"
 723                                 val = 0;
 724                         }
 725                 }
 726                 else
 727                 {
 728                         // Set CC to "Jump Always"
 729                         val = 0;
 730                 }
 731
 732                 if (val < 0 || val > 31)
 733                         return error("condition constant out of range");
 734
 735                 // Store condition code
 736                 reg1 = val;
 737
 738                 if (type == RI_JR)
 739                 {
 740                         // JR cc,n
 741                         if (expr(r_expr, &eval, &eattr, &esym) != OK)
 742                                 return MalformedOpcode(0x0F);
 743
 744                         if ((challoc - ch_size) < 4)
 745                                 chcheck(4L);
 746
 747                         if (!(eattr & DEFINED))
 748                         {
 749                                 AddFixup(FU_WORD | FU_JR, sloc, r_expr);
 750                                 reg2 = 0;
 751                         }
 752                         else
 753                         {
 754                                 reg2 = ((int)(eval - ((orgactive ? orgaddr : sloc) + 2))) / 2;
 755
 756                                 if ((reg2 < -16) || (reg2 > 15))
 757                                         error("PC relative overflow");
 758                         }
 759
 760                         BuildRISCIntructionWord(parm, reg2, reg1);
 761                 }
 762                 else
 763                 {
 764                         // JUMP cc, (Rn)
 765                         if (*tok != '(')
 766                                 return MalformedOpcode(0x10);
 767
 768                         tok++;
 769                         reg2 = GetRegister(FU_REGTWO);
 770
 771                         if (*tok != ')')
 772                                 return MalformedOpcode(0x11);
 773
 774                         tok++;
 775                         at_eol();
 776                         BuildRISCIntructionWord(parm, reg2, reg1);
 777                 }
 778
 779                 break;
 780
 781         // Should never get here :-D
 782         default:
 783                 return error("Unknown RISC opcode type");
 784         }
 785
 786         lastOpcode = type;
 787         return 0;
 788 }
 789