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

   1 //
   2 // RMAC - Reboot's Macro Assembler for all Atari computers
   3 // RISCA.C - GPU/DSP Assembler
   4 // Copyright (C) 199x Landon Dyer, 2011-2018 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 "amode.h"
  11 #include "direct.h"
  12 #include "error.h"
  13 #include "expr.h"
  14 #include "mark.h"
  15 #include "procln.h"
  16 #include "sect.h"
  17 #include "token.h"
  18
  19 #define DEF_MR                          // Declare keyword values
  20 #include "risckw.h"                     // Incl. generated risc keywords
  21
  22 #define DEF_KW                          // Declare keyword values
  23 #include "kwtab.h"                      // Incl. generated keyword tables & defs
  24
  25 #define MAXINTERNCC 26          // Maximum internal condition codes
  26
  27
  28 unsigned altbankok = 0;         // Ok to use alternate register bank
  29 unsigned orgactive = 0;         // RISC/6502 org directive active
  30 unsigned orgaddr = 0;           // Org'd address
  31 unsigned orgwarning = 0;        // Has an ORG warning been issued
  32 int lastOpcode = -1;            // Last RISC opcode assembled
  33 uint8_t riscImmTokenSeen;       // The '#' (immediate) token was seen
  34
  35 static const char reg_err[] = "missing register R0...R31";
  36
  37 // Jaguar jump condition names
  38 static const char condname[MAXINTERNCC][5] = {
  39         "NZ", "Z", "NC", "NCNZ", "NCZ", "C", "CNZ", "CZ", "NN", "NNNZ", "NNZ",
  40         "N", "N_NZ", "N_Z", "T", "A", "NE", "EQ", "CC", "HS", "HI", "CS", "LO",
  41         "PL", "MI", "F"
  42 };
  43
  44 // Jaguar jump condition numbers
  45 static const char condnumber[] = {
  46         1, 2, 4, 5, 6, 8, 9, 10, 20, 21, 22, 24, 25, 26,
  47         0, 0, 1, 2, 4, 4, 5,  8,  8, 20, 24, 31
  48 };
  49
  50 // Opcode Specific Data
  51 struct opcoderecord {
  52         uint16_t state;         // Opcode Name (unused)
  53         uint16_t type;          // Opcode Type
  54         uint16_t param;         // Opcode Parameter
  55 };
  56
  57 static const struct opcoderecord roptbl[] = {
  58         { MR_ADD,     RI_TWO,    0 },
  59         { MR_ADDC,    RI_TWO,    1 },
  60         { MR_ADDQ,    RI_NUM_32, 2 },
  61         { MR_ADDQT,   RI_NUM_32, 3 },
  62         { MR_SUB,     RI_TWO,    4 },
  63         { MR_SUBC,    RI_TWO,    5 },
  64         { MR_SUBQ,    RI_NUM_32, 6 },
  65         { MR_SUBQT,   RI_NUM_32, 7 },
  66         { MR_NEG,     RI_ONE,    8 },
  67         { MR_AND,     RI_TWO,    9 },
  68         { MR_OR,      RI_TWO,    10 },
  69         { MR_XOR,     RI_TWO,    11 },
  70         { MR_NOT,     RI_ONE,    12 },
  71         { MR_BTST,    RI_NUM_31, 13 },
  72         { MR_BSET,    RI_NUM_31, 14 },
  73         { MR_BCLR,    RI_NUM_31, 15 },
  74         { MR_MULT,    RI_TWO,    16 },
  75         { MR_IMULT,   RI_TWO,    17 },
  76         { MR_IMULTN,  RI_TWO,    18 },
  77         { MR_RESMAC,  RI_ONE,    19 },
  78         { MR_IMACN,   RI_TWO,    20 },
  79         { MR_DIV,     RI_TWO,    21 },
  80         { MR_ABS,     RI_ONE,    22 },
  81         { MR_SH,      RI_TWO,    23 },
  82         { MR_SHLQ,    RI_NUM_32, 24 + SUB32 },
  83         { MR_SHRQ,    RI_NUM_32, 25 },
  84         { MR_SHA,     RI_TWO,    26 },
  85         { MR_SHARQ,   RI_NUM_32, 27 },
  86         { MR_ROR,     RI_TWO,    28 },
  87         { MR_RORQ,    RI_NUM_32, 29 },
  88         { MR_ROLQ,    RI_NUM_32, 29 + SUB32 },
  89         { MR_CMP,     RI_TWO,    30 },
  90         { MR_CMPQ,    RI_NUM_15, 31 },
  91         { MR_SAT8,    RI_ONE,    32 + GPUONLY },
  92         { MR_SUBQMOD, RI_NUM_32, 32 + DSPONLY },
  93         { MR_SAT16,   RI_ONE,    33 + GPUONLY },
  94         { MR_SAT16S,  RI_ONE,    33 + DSPONLY },
  95         { MR_MOVEQ,   RI_NUM_31, 35 },
  96         { MR_MOVETA,  RI_TWO,    36 },
  97         { MR_MOVEFA,  RI_TWO,    37 },
  98         { MR_MOVEI,   RI_MOVEI,  38 },
  99         { MR_LOADB,   RI_LOADN,  39 },
 100         { MR_LOADW,   RI_LOADN,  40 },
 101         { MR_LOADP,   RI_LOADN,  42 + GPUONLY },
 102         { MR_SAT32S,  RI_ONE,    42 + DSPONLY },
 103         { MR_STOREB,  RI_STOREN, 45 },
 104         { MR_STOREW,  RI_STOREN, 46 },
 105         { MR_STOREP,  RI_STOREN, 48 + GPUONLY },
 106         { MR_MIRROR,  RI_ONE,    48 + DSPONLY },
 107         { MR_JUMP,    RI_JUMP,   52 },
 108         { MR_JR,      RI_JR,     53 },
 109         { MR_MMULT,   RI_TWO,    54 },
 110         { MR_MTOI,    RI_TWO,    55 },
 111         { MR_NORMI,   RI_TWO,    56 },
 112         { MR_NOP,     RI_NONE,   57 },
 113         { MR_SAT24,   RI_ONE,    62 },
 114         { MR_UNPACK,  RI_ONE,    63 + GPUONLY | (0 << 6) },
 115         { MR_PACK,    RI_ONE,    63 + GPUONLY | (1 << 6) },
 116         { MR_ADDQMOD, RI_NUM_32, 63 + DSPONLY },
 117         { MR_MOVE,    RI_MOVE,   0 },
 118         { MR_LOAD,    RI_LOAD,   0 },
 119         { MR_STORE,   RI_STORE,  0 }
 120 };
 121
 122 #define MALF_NUM                0
 123 #define MALF_EXPR               1
 124 #define MALF_LPAREN             2
 125 #define MALF_RPAREN             3
 126
 127 static const char malform1[] = "missing '#'";
 128 static const char malform2[] = "bad expression";
 129 static const char malform3[] = "missing ')'";
 130 static const char malform4[] = "missing '('";
 131
 132 static const char * malformErr[] = {
 133         malform1, malform2, malform3, malform4
 134 };
 135
 136
 137 //
 138 // Convert a string to uppercase
 139 //
 140 static void strtoupper(char * s)
 141 {
 142         while (*s)
 143                 *s++ &= 0xDF;
 144 }
 145
 146
 147 //
 148 // Function to return "malformed expression" error
 149 // This is done mainly to remove a bunch of GOTO statements in the parser
 150 //
 151 static inline int MalformedOpcode(int signal)
 152 {
 153         return error("Malformed opcode, %s", malformErr[signal]);
 154 }
 155
 156
 157 //
 158 // Function to return "Illegal Indexed Register" error
 159 // Anyone trying to index something other than R14 or R15
 160 //
 161 static inline int IllegalIndexedRegister(int reg)
 162 {
 163         return error("Attempted index reference with non-indexable register (r%d)", reg - KW_R0);
 164 }
 165
 166
 167 //
 168 // Function to return "Illegal Indexed Register" error for EQUR scenarios
 169 // Trying to use register value within EQUR that isn't 14 or 15
 170 //
 171 static inline int IllegalIndexedRegisterEqur(SYM * sy)
 172 {
 173         return error("Attempted index reference with non-indexable register within EQUR (%s = r%d)", sy->sname, sy->svalue);
 174 }
 175
 176
 177 //
 178 // Build up & deposit RISC instruction word
 179 //
 180 static void DepositRISCInstructionWord(uint16_t opcode, int reg1, int reg2)
 181 {
 182         // Check for absolute address setting
 183         if (!orgwarning && !orgactive)
 184         {
 185                 warn("RISC code generated with no origin defined");
 186                 orgwarning = 1;
 187         }
 188
 189         int value = ((opcode & 0x3F) << 10) + ((reg1 & 0x1F) << 5) + (reg2 & 0x1F);
 190         D_word(value);
 191 }
 192
 193
 194 //
 195 // Evaluate the RISC register from the token stream. Passed in value is the
 196 // FIXUP attribute to use if the expression comes back as undefined.
 197 //
 198 static int EvaluateRegisterFromTokenStream(uint32_t attr)
 199 {
 200         uint64_t 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         // Evaluate what's in the global "tok" buffer
 206         if (expr(r_expr, &eval, &eattr, &esym) != OK)
 207                 return ERROR;
 208
 209         if (!(eattr & DEFINED))
 210         {
 211                 AddFixup(FU_WORD | attr, sloc, r_expr);
 212                 return 0;
 213         }
 214
 215         // If we got a register in range (0-31), return it
 216         if (eval <= 31)
 217                 return (int)eval;
 218
 219         // Otherwise, it's out of range & we flag an error
 220         return error(reg_err);
 221 }
 222
 223
 224 //
 225 // Do RISC code generation
 226 //
 227 int GenerateRISCCode(int state)
 228 {
 229         int reg1;                                       // Register 1
 230         int reg2;                                       // Register 2
 231         int val = 0;                            // Constructed value
 232         char scratch[80];
 233         SYM * ccsym;
 234         SYM * sy;
 235         int i, commaFound;
 236         TOKEN * t;
 237         uint16_t attrflg;
 238         int indexed;                            // Indexed register flag
 239
 240         uint64_t eval;                          // Expression value
 241         uint16_t eattr;                                 // Expression attributes
 242         SYM * esym;                                     // External symbol involved in expr.
 243         TOKEN r_expr[EXPRSIZE];         // Expression token list
 244
 245         // Get opcode parameter and type
 246         uint16_t parm = roptbl[state - 3000].param;
 247         uint16_t type = roptbl[state - 3000].type;
 248         riscImmTokenSeen = 0;           // Set to "token not seen yet"
 249
 250         // Detect whether the opcode parmeter passed determines that the opcode is
 251         // specific to only one of the RISC processors and ensure it is legal in
 252         // the current code section. If not then show error and return.
 253         if (((parm & GPUONLY) && rdsp) || ((parm & DSPONLY) && rgpu))
 254                 return error("Opcode is not valid in this code section");
 255
 256         // Process RISC opcode
 257         switch (type)
 258         {
 259         // No operand instructions
 260         // NOP (57)
 261         case RI_NONE:
 262                 DepositRISCInstructionWord(parm, 0, 0);
 263                 break;
 264
 265         // Single operand instructions (Rd)
 266         // ABS, MIRROR, NEG, NOT, PACK, RESMAC, SAT8, SAT16, SAT16S, SAT24, SAT32S,
 267         // UNPACK
 268         case RI_ONE:
 269                 reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 270                 at_eol();
 271                 DepositRISCInstructionWord(parm, parm >> 6, reg2);
 272                 break;
 273
 274         // Two operand instructions (Rs,Rd)
 275         // ADD, ADDC, AND, CMP, DIV, IMACN, IMULT, IMULTN, MOVEFA, MOVETA, MULT,
 276         // MMULT, MTOI, NORMI, OR, ROR, SH, SHA, SUB, SUBC, XOR
 277         case RI_TWO:
 278                 if (parm == 37)
 279                         altbankok = 1;                      // MOVEFA
 280
 281                 reg1 = EvaluateRegisterFromTokenStream(FU_REGONE);
 282                 CHECK_COMMA;
 283
 284                 if (parm == 36)
 285                         altbankok = 1;                      // MOVETA
 286
 287                 reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 288                 at_eol();
 289                 DepositRISCInstructionWord(parm, reg1, reg2);
 290                 break;
 291
 292         // Numeric operand (n,Rd) where n = -16..+15
 293         // CMPQ
 294         case RI_NUM_15:
 295
 296         // Numeric operand (n,Rd) where n = 0..31
 297         // BCLR, BSET, BTST, MOVEQ
 298         case RI_NUM_31:
 299
 300         // Numeric operand (n,Rd) where n = 1..32
 301         // ADDQ, ADDQMOD, ADDQT, SHARQ, SHLQ, SHRQ, SUBQ, SUBQMOD, SUBQT, ROLQ,
 302         // RORQ
 303         case RI_NUM_32:
 304                 switch (type)
 305                 {
 306                 case RI_NUM_15:
 307                         reg1 = -16; reg2 = 15; attrflg = FU_NUM15;
 308                         break;
 309                 default:
 310                 case RI_NUM_31:
 311                         reg1 =   0; reg2 = 31; attrflg = FU_NUM31;
 312                         break;
 313                 case RI_NUM_32:
 314                         reg1 =   1; reg2 = 32; attrflg = FU_NUM32;
 315                         break;
 316                 }
 317
 318                 if (parm & SUB32)
 319                         attrflg |= FU_SUB32;
 320
 321                 if (*tok != '#')
 322                         return MalformedOpcode(MALF_NUM);
 323
 324                 tok++;
 325                 riscImmTokenSeen = 1;
 326
 327                 if (expr(r_expr, &eval, &eattr, &esym) != OK)
 328                         return MalformedOpcode(MALF_EXPR);
 329
 330                 if (!(eattr & DEFINED))
 331                 {
 332                         AddFixup((WORD)(FU_WORD | attrflg), sloc, r_expr);
 333                         reg1 = 0;
 334                 }
 335                 else
 336                 {
 337                         if (((int)eval < reg1) || ((int)eval > reg2))
 338                                 return error("constant out of range (%d to %d", reg1, reg2);
 339
 340                         if (parm & SUB32)
 341                                 reg1 = 32 - (int)eval;
 342                         else if (type == RI_NUM_32)
 343                                 reg1 = (reg1 == 32 ? 0 : (int)eval);
 344                         else
 345                                 reg1 = (int)eval;
 346                 }
 347
 348                 CHECK_COMMA;
 349                 reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 350                 at_eol();
 351                 DepositRISCInstructionWord(parm, reg1, reg2);
 352                 break;
 353
 354         // Move Immediate--n,Rn--n in Second Word
 355         case RI_MOVEI:
 356                 if (*tok != '#')
 357                         return MalformedOpcode(MALF_NUM);
 358
 359                 tok++;
 360                 riscImmTokenSeen = 1;
 361
 362                 // Check for equated register after # and return error if so
 363                 if (*tok == SYMBOL)
 364                 {
 365                         sy = lookup(string[tok[1]], LABEL, 0);
 366
 367                         if (sy && (sy->sattre & EQUATEDREG))
 368                                 return error("equated register in 1st operand of MOVEI instruction");
 369                 }
 370
 371                 if (expr(r_expr, &eval, &eattr, &esym) != OK)
 372                         return MalformedOpcode(MALF_EXPR);
 373
 374                 if ((lastOpcode == RI_JUMP) || (lastOpcode == RI_JR))
 375                 {
 376                         if (legacy_flag)
 377                         {
 378                                 // User doesn't care, emit a NOP to fix
 379                                 DepositRISCInstructionWord(57, 0, 0);
 380                                 warn("MOVEI following JUMP, inserting NOP to fix your BROKEN CODE");
 381                         }
 382                         else
 383                                 warn("MOVEI immediately follows JUMP");
 384                 }
 385
 386                 if (!(eattr & DEFINED))
 387                 {
 388                         AddFixup(FU_LONG | FU_MOVEI, sloc + 2, r_expr);
 389                         eval = 0;
 390                 }
 391                 else
 392                 {
 393                         if (eattr & TDB)
 394                                 MarkRelocatable(cursect, sloc + 2, (eattr & TDB), (MLONG | MMOVEI), NULL);
 395                 }
 396
 397                 CHECK_COMMA;
 398                 reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 399                 at_eol();
 400
 401                 DepositRISCInstructionWord(parm, 0, reg2);
 402                 val = WORDSWAP32(eval);
 403                 D_long(val);
 404                 break;
 405
 406         // PC,Rd or Rs,Rd
 407         case RI_MOVE:
 408                 if (*tok == KW_PC)
 409                 {
 410                         parm = 51;
 411                         reg1 = 0;
 412                         tok++;
 413                 }
 414                 else
 415                 {
 416                         parm = 34;
 417                         reg1 = EvaluateRegisterFromTokenStream(FU_REGONE);
 418                 }
 419
 420                 CHECK_COMMA;
 421                 reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 422                 at_eol();
 423                 DepositRISCInstructionWord(parm, reg1, reg2);
 424                 break;
 425
 426         // (Rn),Rn = 41 / (R14/R15+n),Rn = 43/44 / (R14/R15+Rn),Rn = 58/59
 427         case RI_LOAD:
 428                 indexed = 0;
 429                 parm = 41;
 430
 431                 if (*tok != '(')
 432                         return MalformedOpcode(MALF_LPAREN);
 433
 434                 tok++;
 435
 436         if ((tok[1] == '+') || (tok[1] == '-'))
 437                 {
 438                         // Trying to make indexed call
 439                         if ((*tok == KW_R14) || (*tok == KW_R15))
 440                                 indexed = (*tok - KW_R0);
 441                         else
 442                                 return IllegalIndexedRegister(*tok);
 443                 }
 444
 445                 if (*tok == SYMBOL)
 446                 {
 447                         sy = lookup(string[tok[1]], LABEL, 0);
 448
 449                         if (!sy)
 450                         {
 451                                 error(reg_err);
 452                                 return ERROR;
 453                         }
 454
 455                         if (sy->sattre & EQUATEDREG)
 456                         {
 457                                 if ((tok[2] == '+') || (tok[2] == '-'))
 458                                 {
 459                                         if ((sy->svalue & 0x1F) == 14 || (sy->svalue & 0x1F) == 15) {
 460                                                 indexed = (sy->svalue & 0x1F);
 461                                                 tok++;
 462                                         }
 463                                         else
 464                                                 return IllegalIndexedRegisterEqur(sy);
 465                                 }
 466                         }
 467                 }
 468
 469                 if (!indexed)
 470                 {
 471                         reg1 = EvaluateRegisterFromTokenStream(FU_REGONE);
 472                 }
 473                 else
 474                 {
 475                         reg1 = indexed;
 476                         indexed = 0;
 477                         tok++;
 478
 479                         if (*tok == '+')
 480                         {
 481                                 parm = (WORD)(reg1 - 14 + 58);
 482                                 tok++;
 483
 484                                 if ((*tok >= KW_R0) && (*tok <= KW_R31))
 485                                         indexed = 1;
 486
 487                                 if (*tok == SYMBOL)
 488                                 {
 489                                         sy = lookup(string[tok[1]], LABEL, 0);
 490
 491                                         if (!sy)
 492                                         {
 493                                                 error(reg_err);
 494                                                 return ERROR;
 495                                         }
 496
 497                                         if (sy->sattre & EQUATEDREG)
 498                                                 indexed = 1;
 499                                 }
 500
 501                                 if (indexed)
 502                                 {
 503                                         reg1 = EvaluateRegisterFromTokenStream(FU_REGONE);
 504                                 }
 505                                 else
 506                                 {
 507                                         if (expr(r_expr, &eval, &eattr, &esym) != OK)
 508                                                 return MalformedOpcode(MALF_EXPR);
 509
 510                                         if (!(eattr & DEFINED))
 511                                                 return error("constant expected after '+'");
 512
 513                                         reg1 = (int)eval;
 514
 515                                         if (reg1 == 0)
 516                                         {
 517                                                 reg1 = 14 + (parm - 58);
 518                                                 parm = 41;
 519                                                 warn("NULL offset in LOAD ignored");
 520                                         }
 521                                         else
 522                                         {
 523                                                 if ((reg1 < 1) || (reg1 > 32))
 524                                                         return error("constant in LOAD out of range (1-32)");
 525
 526                                                 if (reg1 == 32)
 527                                                         reg1 = 0;
 528
 529                                                 parm = (WORD)(parm - 58 + 43);
 530                                         }
 531                                 }
 532                         }
 533                         else
 534                         {
 535                                 reg1 = EvaluateRegisterFromTokenStream(FU_REGONE);
 536                         }
 537                 }
 538
 539                 if (*tok != ')')
 540                         return MalformedOpcode(MALF_RPAREN);
 541
 542                 tok++;
 543                 CHECK_COMMA;
 544                 reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 545                 at_eol();
 546                 DepositRISCInstructionWord(parm, reg1, reg2);
 547                 break;
 548
 549         // Rn,(Rn) = 47 / Rn,(R14/R15+n) = 49/50 / Rn,(R14/R15+Rn) = 60/61
 550         case RI_STORE:
 551                 parm = 47;
 552                 reg1 = EvaluateRegisterFromTokenStream(FU_REGONE);
 553                 CHECK_COMMA;
 554
 555                 if (*tok != '(')
 556                         return MalformedOpcode(MALF_LPAREN);
 557
 558                 tok++;
 559                 indexed = 0;
 560
 561                 if (((*tok == KW_R14) || (*tok == KW_R15)) && (tok[1] != ')'))
 562                         indexed = *tok - KW_R0;
 563
 564                 if (*tok == SYMBOL)
 565                 {
 566                         sy = lookup(string[tok[1]], LABEL, 0);
 567
 568                         if (!sy)
 569                         {
 570                                 error(reg_err);
 571                                 return ERROR;
 572                         }
 573
 574                         if (sy->sattre & EQUATEDREG)
 575                         {
 576                                 if (((sy->svalue & 0x1F) == 14 || (sy->svalue & 0x1F) == 15)
 577                                         && (tok[2] != ')'))
 578                                 {
 579                                         indexed = (sy->svalue & 0x1F);
 580                                         tok++;
 581                                 }
 582                         }
 583                 }
 584
 585                 if (!indexed)
 586                 {
 587                         reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 588                 }
 589                 else
 590                 {
 591                         reg2 = indexed;
 592                         indexed = 0;
 593                         tok++;
 594
 595                         if (*tok == '+')
 596                         {
 597                                 parm = (WORD)(reg2 - 14 + 60);
 598                                 tok++;
 599
 600                                 if ((*tok >= KW_R0) && (*tok <= KW_R31))
 601                                         indexed = 1;
 602
 603                                 if (*tok == SYMBOL)
 604                                 {
 605                                         sy = lookup(string[tok[1]], LABEL, 0);
 606
 607                                         if (!sy)
 608                                         {
 609                                                 error(reg_err);
 610                                                 return ERROR;
 611                                         }
 612
 613                                         if (sy->sattre & EQUATEDREG)
 614                                                 indexed = 1;
 615                                 }
 616
 617                                 if (indexed)
 618                                 {
 619                                         reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 620                                 }
 621                                 else
 622                                 {
 623                                         if (expr(r_expr, &eval, &eattr, &esym) != OK)
 624                                                 return MalformedOpcode(MALF_EXPR);
 625
 626                                         if (!(eattr & DEFINED))
 627                                         {
 628                                                 AddFixup(FU_WORD | FU_REGTWO, sloc, r_expr);
 629                                                 reg2 = 0;
 630                                         }
 631                                         else
 632                                         {
 633                                                 reg2 = (int)eval;
 634
 635                                                 if (reg2 == 0)
 636                                                 {
 637                                                         reg2 = 14 + (parm - 60);
 638                                                         parm = 47;
 639                                                         warn("NULL offset in STORE ignored");
 640                                                 }
 641                                                 else
 642                                                 {
 643                                                         if ((reg2 < 1) || (reg2 > 32))
 644                                                                 return error("constant in STORE out of range (1-32)");
 645
 646                                                         if (reg2 == 32)
 647                                                                 reg2 = 0;
 648
 649                                                         parm = (WORD)(parm - 60 + 49);
 650                                                 }
 651                                         }
 652                                 }
 653                         }
 654                         else
 655                         {
 656                                 reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 657                         }
 658                 }
 659
 660                 if (*tok != ')')
 661                         return MalformedOpcode(MALF_RPAREN);
 662
 663                 tok++;
 664                 at_eol();
 665                 DepositRISCInstructionWord(parm, reg2, reg1);
 666                 break;
 667
 668         // LOADB/LOADP/LOADW (Rn),Rn
 669         case RI_LOADN:
 670                 if (*tok != '(')
 671                         return MalformedOpcode(MALF_LPAREN);
 672
 673                 tok++;
 674                 reg1 = EvaluateRegisterFromTokenStream(FU_REGONE);
 675
 676                 if (*tok != ')')
 677                         return MalformedOpcode(MALF_RPAREN);
 678
 679                 tok++;
 680                 CHECK_COMMA;
 681                 reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 682                 at_eol();
 683                 DepositRISCInstructionWord(parm, reg1, reg2);
 684                 break;
 685
 686         // STOREB/STOREP/STOREW Rn,(Rn)
 687         case RI_STOREN:
 688                 reg1 = EvaluateRegisterFromTokenStream(FU_REGONE);
 689                 CHECK_COMMA;
 690
 691                 if (*tok != '(')
 692                         return MalformedOpcode(MALF_LPAREN);
 693
 694                 tok++;
 695                 reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 696
 697                 if (*tok != ')')
 698                         return MalformedOpcode(MALF_RPAREN);
 699
 700                 tok++;
 701                 at_eol();
 702                 DepositRISCInstructionWord(parm, reg2, reg1);
 703                 break;
 704
 705         // Jump Relative - cc,n - n=-16..+15 words, reg2=cc
 706         case RI_JR:
 707
 708         // Jump Absolute - cc,(Rs) - reg2=cc
 709         case RI_JUMP:
 710                 // Check to see if there is a comma in the token string. If not then
 711                 // the JR or JUMP should default to 0, Jump Always
 712                 commaFound = 0;
 713
 714                 for(t=tok; *t!=EOL; t++)
 715                 {
 716                         if (*t == ',')
 717                         {
 718                                 commaFound = 1;
 719                                 break;
 720                         }
 721                 }
 722
 723                 if (commaFound)
 724                 {
 725                         if (*tok == CONST)
 726                         {
 727                                 // CC using a constant number (O_o)
 728                                 PTR tp;
 729                                 tp.tk = tok + 1;
 730                                 val = *tp.i64++;
 731                                 tok = tp.tk;
 732                                 CHECK_COMMA;
 733                         }
 734                         else if (*tok == SYMBOL)
 735                         {
 736                                 val = 9999;
 737                                 strcpy(scratch, string[tok[1]]);
 738                                 strtoupper(scratch);
 739
 740                                 for(i=0; i<MAXINTERNCC; i++)
 741                                 {
 742                                         // Look for the condition code & break if found
 743                                         if (strcmp(condname[i], scratch) == 0)
 744                                         {
 745                                                 val = condnumber[i];
 746                                                 break;
 747                                         }
 748                                 }
 749
 750                                 // Standard CC was not found, look for an equated one
 751                                 if (val == 9999)
 752                                 {
 753                                         ccsym = lookup(string[tok[1]], LABEL, 0);
 754
 755                                         if (ccsym && (ccsym->sattre & EQUATEDCC) && !(ccsym->sattre & UNDEF_CC))
 756                                                 val = (int)ccsym->svalue;
 757                                         else
 758                                                 return error("unknown condition code");
 759                                 }
 760
 761                                 tok += 2;
 762                                 CHECK_COMMA;
 763                         }
 764                         else if (*tok == '(')
 765                         {
 766                                 // Set CC to "Jump Always"
 767                                 val = 0;
 768                         }
 769                 }
 770                 else
 771                 {
 772                         // Set CC to "Jump Always"
 773                         val = 0;
 774                 }
 775
 776                 if ((val < 0) || (val > 31))
 777                         return error("condition constant out of range");
 778
 779                 // Store condition code
 780                 reg1 = val;
 781
 782                 if (type == RI_JR)
 783                 {
 784                         // JR cc,n
 785                         if (expr(r_expr, &eval, &eattr, &esym) != OK)
 786                                 return MalformedOpcode(MALF_EXPR);
 787
 788                         if (!(eattr & DEFINED))
 789                         {
 790                                 AddFixup(FU_WORD | FU_JR, sloc, r_expr);
 791                                 reg2 = 0;
 792                         }
 793                         else
 794                         {
 795                                 reg2 = ((int)(eval - ((orgactive ? orgaddr : sloc) + 2))) / 2;
 796
 797                                 if ((reg2 < -16) || (reg2 > 15))
 798                                         error("PC relative overflow in JR (outside of -16 to 15)");
 799                         }
 800                 }
 801                 else
 802                 {
 803                         // JUMP cc, (Rn)
 804                         if (*tok != '(')
 805                                 return MalformedOpcode(MALF_LPAREN);
 806
 807                         tok++;
 808                         reg2 = EvaluateRegisterFromTokenStream(FU_REGTWO);
 809
 810                         if (*tok != ')')
 811                                 return MalformedOpcode(MALF_RPAREN);
 812
 813                         tok++;
 814                         at_eol();
 815                 }
 816
 817                 DepositRISCInstructionWord(parm, reg2, reg1);
 818                 break;
 819
 820         // We should never get here. If we do, somebody done fucked up. :-D
 821         default:
 822                 return error("Unknown RISC opcode type");
 823         }
 824
 825         lastOpcode = type;
 826         return 0;
 827 }
 828