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

   1 //
   2 // RMAC - Reboot's Macro Assembler for the Atari Jaguar Console System
   3 // PROCLN.C - Line Processing
   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 "procln.h"
  10 #include "listing.h"
  11 #include "amode.h"
  12 #include "error.h"
  13 #include "sect.h"
  14 #include "expr.h"
  15 #include "mach.h"
  16 #include "direct.h"
  17 #include "macro.h"
  18 #include "symbol.h"
  19 #include "riscasm.h"
  20
  21 #define DEF_KW                                  // Declare keyword values
  22 #include "kwtab.h"                              // Incl generated keyword tables & defs
  23
  24 #define DEF_MN                                  // Incl 68k keyword definitions
  25 #define DECL_MN                                 // Incl 68k keyword state machine tables
  26 #include "mntab.h"
  27
  28 #define DEF_MR
  29 #define DECL_MR
  30 #include "risckw.h"
  31
  32
  33 IFENT * ifent;                                  // Current ifent
  34 static IFENT ifent0;                    // Root ifent
  35 static IFENT * f_ifent;                 // Freelist of ifents
  36 static int disabled;                    // Assembly conditionally disabled
  37 int just_bss;                                   // 1, ds.b in microprocessor mode
  38 VALUE pcloc;                                    // Value of "PC" at beginning of line
  39 IFENT * ifent;                                  // Current ifent
  40 SYM * lab_sym;                                  // Label on line (or NULL)
  41
  42 const char extra_stuff[] = "extra (unexpected) text found after addressing mode";
  43 const char comma_error[] = "missing comma";
  44 const char syntax_error[] = "syntax error";
  45 const char locgl_error[] = "cannot GLOBL local symbol";
  46 const char lab_ignored[] = "label ignored";
  47
  48 // Table to convert an addressing-mode number to a bitmask.
  49 LONG amsktab[0112] = {
  50         M_DREG, M_DREG, M_DREG, M_DREG,
  51         M_DREG, M_DREG, M_DREG, M_DREG,
  52
  53         M_AREG, M_AREG, M_AREG, M_AREG,
  54         M_AREG, M_AREG, M_AREG, M_AREG,
  55
  56         M_AIND, M_AIND, M_AIND, M_AIND,
  57         M_AIND, M_AIND, M_AIND, M_AIND,
  58
  59         M_APOSTINC, M_APOSTINC, M_APOSTINC, M_APOSTINC,
  60         M_APOSTINC, M_APOSTINC, M_APOSTINC, M_APOSTINC,
  61
  62         M_APREDEC, M_APREDEC, M_APREDEC, M_APREDEC,
  63         M_APREDEC, M_APREDEC, M_APREDEC, M_APREDEC,
  64
  65         M_ADISP, M_ADISP, M_ADISP, M_ADISP,
  66         M_ADISP, M_ADISP, M_ADISP, M_ADISP,
  67
  68         M_AINDEXED, M_AINDEXED, M_AINDEXED, M_AINDEXED,
  69         M_AINDEXED, M_AINDEXED, M_AINDEXED, M_AINDEXED,
  70
  71         M_ABSW,                                                                                 // 070
  72         M_ABSL,                                                                                 // 071
  73         M_PCDISP,                                                                               // 072
  74         M_PCINDEXED,                                                                    // 073
  75         M_IMMED,                                                                                // 074
  76         0L,                                                                                             // 075
  77         0L,                                                                                             // 076
  78         0L,                                                                                             // 077
  79         M_ABASE,                                                                                // 0100
  80         M_MEMPOST,                                                                              // 0101
  81         M_MEMPRE,                                                                               // 0102
  82         M_PCBASE,                                                                               // 0103
  83         M_PCMPOST,                                                                              // 0104
  84         M_PCMPRE,                                                                               // 0105
  85         M_AM_USP,                                                                               // 0106
  86         M_AM_SR,                                                                                // 0107
  87         M_AM_CCR,                                                                               // 0110
  88         M_AM_NONE                                                                               // 0111
  89 };                                                                                                      // 0112 length
  90
  91
  92 // Function prototypes
  93 int HandleLabel(char *, int);
  94
  95
  96 //
  97 // Initialize Line Processor
  98 //
  99 void InitLineProcessor(void)
 100 {
 101         disabled = 0;
 102         ifent = &ifent0;
 103         f_ifent = ifent0.if_prev = NULL;
 104         ifent0.if_state = 0;
 105 }
 106
 107
 108 //
 109 // Line Processor
 110 //
 111 void Assemble(void)
 112 {
 113         int state;                                      // Keyword machine state (output)
 114         int j;                                          // Random int, must be fast
 115         char * p;                                       // Random char ptr, must be fast
 116         TOKEN * tk;                                     // First token in line
 117         char * label;                           // Symbol (or NULL)
 118         char * equate;                          // Symbol (or NULL)
 119         int labtyp = 0;                         // Label type (':', DCOLON)
 120         int equtyp = 0;                         // Equ type ('=', DEQUALS)
 121         VALUE eval;                                     // Expression value
 122         WORD eattr;                                     // Expression attributes
 123         SYM * esym;                                     // External symbol involved in expr.
 124         WORD siz = 0;                           // Size suffix to mnem/diretve/macro
 125         LONG amsk0, amsk1;                      // Address-type masks for ea0, ea1
 126         MNTAB * m;                                      // Code generation table pointer
 127         SYM * sy, * sy2;                        // Symbol (temp usage)
 128         char * opname = NULL;           // Name of dirctve/mnemonic/macro
 129         int listflag;                           // 0: Don't call listeol()
 130         WORD rmask;                                     // Register list, for REG
 131         int registerbank;                       // RISC register bank
 132         int riscreg;                            // RISC register
 133         listflag = 0;                           // Initialise listing flag
 134
 135 loop:                                                   // Line processing loop label
 136
 137         // Get another line of tokens
 138         if (TokenizeLine() == TKEOF)
 139         {
 140 if (verb_flag) printf("Assemble: Found TKEOF flag...\n");
 141                 if (list_flag && listflag)                      // Flush last line of source
 142                         listeol();
 143
 144                 if (ifent->if_prev != NULL)                     // Check conditional token
 145                         error("hit EOF without finding matching .endif");
 146
 147                 return;
 148         }
 149
 150         DEBUG DumpTokenBuffer();
 151
 152         if (list_flag)
 153         {
 154                 if (listflag && listing > 0)
 155                         listeol();                                              // Tell listing generator about EOL
 156
 157                 lstout((char)(disabled ? '-' : lntag)); // Prepare new line for listing
 158                 listflag = 1;                                           // OK to call `listeol' now
 159                 just_bss = 0;                                           // Reset just_bss mode
 160         }
 161
 162         state = -3;                                                             // No keyword (just EOL)
 163         label = NULL;                                                   // No label
 164         lab_sym = NULL;                                                 // No (exported) label
 165         equate = NULL;                                                  // No equate
 166         tk = tok;                                                               // Save first token in line
 167         pcloc = (VALUE)sloc;                                    // Set beginning-of-line PC
 168
 169 loop1:                                                                          // Internal line processing loop
 170
 171         if (*tok == EOL)                                                // Restart loop if end-of-line
 172                 goto loop;
 173
 174         // First token MUST be a symbol (Shamus: not sure why :-/)
 175         if (*tok != SYMBOL)
 176         {
 177                 error("syntax error; expected symbol");
 178                 goto loop;
 179         }
 180
 181         j = (int)tok[2];                                                // Skip equates (normal statements)
 182
 183         if (j == '=' || j == DEQUALS || j == SET || j == REG || j == EQUREG || j == CCDEF)
 184         {
 185                 equate = string[tok[1]];
 186                 equtyp = j;
 187                 tok += 3;
 188                 goto normal;
 189         }
 190
 191         // Skip past label (but record it)
 192         if (j == ':' || j == DCOLON)
 193         {
 194 as68label:
 195                 label = string[tok[1]];                         // Get label name
 196                 labtyp = tok[2];                                        // Get label type
 197                 tok += 3;                                                       // Go to next line token
 198
 199                 // AS68 MODE:
 200                 // Looks like another label follows the previous one, so handle
 201                 // the previous one until there aren't any more
 202                 if (as68_flag && (*tok == SYMBOL && tok[2] == ':'))
 203                 {
 204                         if (HandleLabel(label, labtyp) != 0)
 205                                 goto loop;
 206
 207                         goto as68label;
 208                 }
 209         }
 210
 211         // EOL is legal here...
 212         if (*tok == EOL)
 213                 goto normal;
 214
 215         // Next token MUST be a symbol
 216         if (*tok++ != SYMBOL)
 217         {
 218                 error("syntax error; expected symbol");
 219                 goto loop;
 220         }
 221
 222         opname = p = string[*tok++];
 223
 224         // Check to see if the SYMBOL is a keyword (a mnemonic or directive).
 225         // On output, `state' will have one of the values:
 226         //    -3          there was no symbol (EOL)
 227         //    -2..-1      the symbol didn't match any keyword
 228         //    0..499      vanilla directives (dc, ds, etc.)
 229         //    500..999    electric directives (macro, rept, etc.)
 230         //    1000..+     mnemonics (move, lsr, etc.)
 231         for(state=0; state>=0;)
 232         {
 233                 j = mnbase[state] + (int)tolowertab[*p];
 234
 235                 // Reject, character doesn't match
 236                 if (mncheck[j] != state)
 237                 {
 238                         state = -1;                                             // No match
 239                         break;
 240                 }
 241
 242                 // Must accept or reject at EOS
 243                 if (!*++p)
 244                 {
 245                         state = mnaccept[j];                    // (-1 on no terminal match)
 246                         break;
 247                 }
 248
 249                 state = mntab[j];
 250         }
 251
 252         // Check for ".b" ".w" ".l" after directive, macro or mnemonic.
 253         siz = SIZN;
 254
 255         if (*tok == DOTW)
 256                 siz = SIZW, tok++;
 257         else if (*tok == DOTL)
 258                 siz = SIZL, tok++;
 259         else if (*tok == DOTB)
 260                 siz = SIZB, tok++;
 261
 262         // Do special directives (500..999) (These must be handled in "real time")
 263         if (state >= 500 && state < 1000)
 264         {
 265                 switch (state)
 266                 {
 267                 case MN_IF:
 268                         d_if ();
 269                 goto loop;
 270                 case MN_ELSE:
 271                         d_else();
 272                         goto loop;
 273                 case MN_ENDIF:
 274                         d_endif ();
 275                         goto loop;
 276                 case MN_IIF:                                            // .iif --- immediate if
 277                         if (disabled || expr(exprbuf, &eval, &eattr, &esym) != OK)
 278                                 goto loop;
 279
 280                         if (!(eattr & DEFINED))
 281                         {
 282                                 error(undef_error);
 283                                 goto loop;
 284                         }
 285
 286                         if (*tok++ != ',')
 287                         {
 288                                 error(comma_error);
 289                                 goto loop;
 290                         }
 291
 292                         if (eval == 0)
 293                                 goto loop;
 294
 295                         goto loop1;
 296                 case MN_MACRO:                                          // .macro --- macro definition
 297                         if (!disabled)
 298                         {
 299                                 // Label on a macro definition is bad mojo... Warn the user
 300                                 if (label != NULL)
 301                                         warn(lab_ignored);
 302
 303                                 DefineMacro();
 304                         }
 305
 306                         goto loop;
 307                 case MN_EXITM:                                          // .exitm --- exit macro
 308                 case MN_ENDM:                                           // .endm --- same as .exitm
 309                         if (!disabled)
 310                         {
 311                                 if (label != NULL)
 312                                         warn(lab_ignored);
 313
 314                                 ExitMacro();
 315                         }
 316
 317                         goto loop;
 318                 case MN_REPT:
 319                         if (!disabled)
 320                         {
 321                                 // Handle labels on REPT directive lines...
 322                                 if (label)
 323                                 {
 324                                         if (HandleLabel(label, labtyp) != 0)
 325                                                 goto loop;
 326                                 }
 327
 328                                 defrept();
 329                         }
 330
 331                         goto loop;
 332                 case MN_ENDR:
 333                         if (!disabled)
 334                                 error("mis-nested .endr");
 335
 336                         goto loop;
 337                 }
 338         }
 339
 340 normal:
 341         if (disabled)                                                   // Conditionally disabled code
 342                 goto loop;
 343
 344         // Do equates
 345         if (equate != NULL)
 346         {
 347                 // Pick global or local symbol enviroment
 348                 j = (*equate == '.' ? curenv : 0);
 349                 sy = lookup(equate, LABEL, j);
 350
 351                 if (sy == NULL)
 352                 {
 353                         sy = NewSymbol(equate, LABEL, j);
 354                         sy->sattr = 0;
 355
 356                         if (equtyp == DEQUALS)
 357                         {
 358                                 // Can't GLOBAL a local symbol
 359                                 if (j)
 360                                 {
 361                                         error(locgl_error);
 362                                         goto loop;
 363                                 }
 364
 365                                 sy->sattr = GLOBAL;
 366                         }
 367                 }
 368                 else if ((sy->sattr & DEFINED) && equtyp != SET)
 369                 {
 370                         if ((equtyp == EQUREG) && (sy->sattre & UNDEF_EQUR))
 371                         {
 372 //REALLY?                               sy->sattre |= ~UNDEF_EQUR;
 373                                 sy->sattre &= ~UNDEF_EQUR;
 374                                 sy->svalue  = 0;
 375                         }
 376                         else if ((equtyp == CCDEF) && (sy->sattre & UNDEF_CC))
 377                         {
 378 //REALLY?                               sy->sattre |= ~UNDEF_CC;
 379                                 sy->sattre &= ~UNDEF_CC;
 380                                 sy->svalue = 0;
 381                         }
 382                         else
 383                         {
 384                                 errors("multiple equate to '%s'", sy->sname);
 385                                 goto loop;
 386                         }
 387                 }
 388
 389                 // Put symbol in "order of definition" list
 390                 if (!(sy->sattr & SDECLLIST))
 391                         AddToSymbolOrderList(sy);
 392
 393                 // Parse value to equate symbol to;
 394                 // o  .equr
 395                 // o  .reg
 396                 // o  everything else
 397                 if (equtyp == EQUREG)
 398                 {
 399 //Linko's request to issue a warning on labels that equated to the same register
 400 //would go here. Not sure how to implement it though. :-/
 401 /*
 402 Maybe like this way:
 403 have an array of bools with 64 entries. Whenever a register is equated, set the
 404 corresponding register bool to true. Whenever it's undef'ed, set it to false. When
 405 checking to see if it's already been equated, issue a warning.
 406 */
 407                         // Check that we are in a RISC section
 408                         if (!rgpu && !rdsp)
 409                         {
 410                                 error(".equr/.regequ must be defined in .gpu/.dsp section");
 411                                 goto loop;
 412                         }
 413
 414                         // Check for register to equate to
 415                         if ((*tok >= KW_R0) && (*tok <= KW_R31))
 416                         {
 417 //                              sy->sattre  = EQUATEDREG | RISCSYM;     // Mark as equated register
 418                                 sy->sattre  = EQUATEDREG;       // Mark as equated register
 419                                 riscreg = (*tok - KW_R0);
 420 //is there any reason to do this, since we're putting this in svalue?
 421 //i'm thinking, no. Let's test that out! :-D
 422 //                              sy->sattre |= (riscreg << 8);           // Store register number
 423 //everything seems to build fine without it... We'll leave it here Just In Case(tm)
 424
 425 #define DEBODGE_REGBANK
 426 #ifdef DEBODGE_REGBANK
 427                                 // Default is current state of "regbank"
 428                                 registerbank = regbank;
 429 #else
 430                                 // Default is no register bank specified
 431                                 registerbank = BANK_N;
 432 #endif
 433
 434                                 // Check for ",<bank #>" override notation
 435                                 if ((tok[1] == ',') && (tok[2] == CONST))
 436                                 {
 437                                         // Advance token pointer to the constant
 438                                         tok += 3;
 439
 440                                         // Anything other than a 0 or a 1 will result in "No Bank"
 441                                         if (*tok == 0)
 442                                                 registerbank = BANK_0;
 443                                         else if (*tok == 1)
 444                                                 registerbank = BANK_1;
 445                                 }
 446
 447 #ifdef DEBODGE_REGBANK
 448                                 sy->sattre |= registerbank;     // Store register bank
 449 #else
 450 // What needs to happen here is to prime registerbank with regbank, then use
 451 // registerbank down below for the bank marking.
 452 #warning "!!! regbank <-> registerbank confusion here !!!"
 453 // The question here is why, if we're allowed to override the ".regbankN" rules
 454 // above, then why is it using the one set by the directive in the extended
 455 // attributes and not in what ends up in symbol->svalue?
 456 // ".regbankN" is not an original Madmac directive, so it's suspect
 457                                 sy->sattre |= regbank;          // Store register bank
 458 #endif
 459                                 eattr = ABS | DEFINED | GLOBAL;
 460 // & what does this $80000080 constant mean???
 461 //                              eval = 0x80000080 + (riscreg) + (registerbank << 8);
 462                                 eval = riscreg;
 463                                 tok++;
 464                         }
 465                         // Checking for a register symbol
 466                         else if (tok[0] == SYMBOL)
 467                         {
 468                                 sy2 = lookup(string[tok[1]], LABEL, j);
 469
 470                                 // Make sure symbol is a valid equreg
 471                                 if (!sy2 || !(sy2->sattre & EQUATEDREG))
 472                                 {
 473                                         error("invalid GPU/DSP .equr/.regequ definition");
 474                                         goto loop;
 475                                 }
 476                                 else
 477                                 {
 478                                         eattr = ABS | DEFINED | GLOBAL; // Copy symbols attributes
 479                                         sy->sattre = sy2->sattre;
 480                                         eval = (sy2->svalue & 0xFFFFF0FF);
 481                                         tok += 2;
 482                                 }
 483                         }
 484                         else
 485                         {
 486                                 error("invalid GPU/DSP .equr/.regequ definition");
 487                                 goto loop;
 488                         }
 489                 }
 490                 else if (equtyp == REG)
 491                 {
 492                         if (reglist(&rmask) < 0)
 493                                 goto loop;
 494
 495                         eval = (VALUE)rmask;
 496                         eattr = ABS | DEFINED;
 497                 }
 498                 else if (equtyp == CCDEF)
 499                 {
 500                         sy->sattre |= EQUATEDCC;
 501                         eattr = ABS | DEFINED | GLOBAL;
 502
 503                         if (tok[0] == SYMBOL)
 504                         {
 505                                 sy2 = lookup(string[tok[1]], LABEL, j);
 506
 507                                 if (!sy2 || !(sy2->sattre & EQUATEDCC))
 508                                 {
 509                                         error("invalid gpu/dsp .ccdef definition");
 510                                         goto loop;
 511                                 }
 512                                 else
 513                                 {
 514                                         eattr = ABS | DEFINED | GLOBAL;
 515                                         sy->sattre = sy2->sattre;
 516                                         eval = sy2->svalue;
 517                                         tok += 2;
 518                                 }
 519                         }
 520                         else if (expr(exprbuf, &eval, &eattr, &esym) != OK)
 521                                 goto loop;
 522                 }
 523                 //equ a equr
 524                 else if (*tok == SYMBOL)
 525                 {
 526                         sy2 = lookup(string[tok[1]], LABEL, j);
 527
 528                         if (sy2 && (sy2->sattre & EQUATEDREG))
 529                         {
 530                                 sy->stype = sy2->stype;
 531                                 sy->sattr = sy2->sattr;
 532                                 sy->sattre = sy2->sattre;
 533 //ICK                           sy->svalue = (sy2->svalue & 0xFFFFF0FF);
 534                                 sy->svalue = sy2->svalue;
 535                                 goto loop;
 536                         }
 537                         else if (expr(exprbuf, &eval, &eattr, &esym) != OK)
 538                                 goto loop;
 539                 }
 540                 else if (expr(exprbuf, &eval, &eattr, &esym) != OK)
 541                         goto loop;
 542
 543                 if (!(eattr & DEFINED))
 544                 {
 545                         error(undef_error);
 546                         goto loop;
 547                 }
 548
 549                 sy->sattr |= eattr | EQUATED;   // Symbol inherits value and attributes
 550                 sy->svalue = eval;
 551
 552                 if (list_flag)                                  // Put value in listing
 553                         listvalue(eval);
 554
 555                 at_eol();                                               // Must be at EOL now
 556                 goto loop;
 557         }
 558
 559         // Do labels
 560         if (label != NULL)
 561         {
 562                 // Non-zero == error occurred
 563                 if (HandleLabel(label, labtyp) != 0)
 564                         goto loop;
 565         }
 566
 567         // Punt on EOL
 568         if (state == -3)
 569                 goto loop;
 570
 571         // If we are in GPU or DSP mode and still in need of a mnemonic then search
 572         // for one
 573         if ((rgpu || rdsp) && (state < 0 || state >= 1000))
 574         {
 575                 for(state=0, p=opname; state>=0;)
 576                 {
 577                         j = mrbase[state] + (int)tolowertab[*p];
 578
 579                         // Reject, character doesn't match
 580                         if (mrcheck[j] != state)
 581                         {
 582                                 state = -1;                                     // No match
 583                                 break;
 584                         }
 585
 586                         // Must accept or reject at EOS
 587                         if (!*++p)
 588                         {
 589                                 state = mraccept[j];            // (-1 on no terminal match)
 590                                 break;
 591                         }
 592
 593                         state = mrtab[j];
 594                 }
 595
 596                 // Call RISC code generator if we found a mnemonic
 597                 if (state >= 3000)
 598                 {
 599                         GenerateRISCCode(state);
 600                         goto loop;
 601                 }
 602         }
 603
 604         // Invoke macro or complain about bad mnemonic
 605         if (state < 0)
 606         {
 607                 if ((sy = lookup(opname, MACRO, 0)) != NULL)
 608                         InvokeMacro(sy, siz);
 609                 else
 610                         errors("unknown op '%s'", opname);
 611
 612                 goto loop;
 613         }
 614
 615         // Call directive handlers
 616         if (state < 500)
 617         {
 618                 (*dirtab[state])(siz);
 619                 goto loop;
 620         }
 621
 622         // Do mnemonics
 623         // o  can't deposit instrs in BSS or ABS
 624         // o  do automatic .EVEN for instrs
 625         // o  allocate space for largest possible instr
 626         // o  can't do ".b" operations with an address register
 627         if (scattr & SBSS)
 628         {
 629                 error("cannot initialize non-storage (BSS) section");
 630                 goto loop;
 631         }
 632
 633         if (sloc & 1)                                                   // Automatic .even
 634                 auto_even();
 635
 636         if (challoc - ch_size < 18)                             // Make sure have space in current chunk
 637                 chcheck(0);
 638
 639         m = &machtab[state - 1000];
 640
 641         // Call special-mode handler
 642         if (m->mnattr & CGSPECIAL)
 643         {
 644                 (*m->mnfunc)(m->mninst, siz);
 645                 goto loop;
 646         }
 647
 648         if (amode(1) < 0)                                               // Parse 0, 1 or 2 addr modes
 649                 goto loop;
 650
 651         if (*tok != EOL)
 652                 error(extra_stuff);
 653
 654         amsk0 = amsktab[am0];
 655         amsk1 = amsktab[am1];
 656
 657         // Catch attempts to use ".B" with an address register (yes, this check
 658         // does work at this level)
 659         if (siz == SIZB && (am0 == AREG || am1 == AREG))
 660         {
 661                 error("cannot use '.b' with an address register");
 662                 goto loop;
 663         }
 664
 665         for(;;)
 666         {
 667                 if ((m->mnattr & siz) && (amsk0 & m->mn0) != 0 && (amsk1 & m->mn1) != 0)
 668                 {
 669                         (*m->mnfunc)(m->mninst, siz);
 670                         goto loop;
 671                 }
 672
 673                 m = &machtab[m->mncont];
 674         }
 675 }
 676
 677
 678 //
 679 // Handle the creation of labels
 680 //
 681 int HandleLabel(char * label, int labelType)
 682 {
 683         // Check for dot in front of label; means this is a local label if present
 684         int environment = (*label == '.' ? curenv : 0);
 685         SYM * symbol = lookup(label, LABEL, environment);
 686
 687         if (symbol == NULL)
 688         {
 689                 symbol = NewSymbol(label, LABEL, environment);
 690                 symbol->sattr = 0;
 691 //              symbol->sattre = RISCSYM;
 692                 symbol->sattre = 0;
 693         }
 694         else if (symbol->sattr & DEFINED)
 695                 return errors("multiply-defined label '%s'", label);
 696
 697         // Put symbol in "order of definition" list
 698         if (!(symbol->sattr & SDECLLIST))
 699                 AddToSymbolOrderList(symbol);
 700
 701         if (orgactive)
 702         {
 703                 symbol->svalue = orgaddr;
 704                 symbol->sattr |= ABS | DEFINED | EQUATED;
 705         }
 706         else
 707         {
 708                 symbol->svalue = sloc;
 709                 symbol->sattr |= DEFINED | cursect;
 710         }
 711
 712         lab_sym = symbol;
 713
 714         if (0 == environment)
 715                 curenv++;
 716
 717         // Make label global if it has a double colon
 718         if (labelType == DCOLON)
 719         {
 720                 if (environment != 0)
 721                         return error(locgl_error);
 722
 723                 symbol->sattr |= GLOBAL;
 724         }
 725
 726         return 0;
 727 }
 728
 729
 730 //
 731 // .if, Start Conditional Assembly
 732 //
 733 int d_if(void)
 734 {
 735         IFENT * rif;
 736         WORD eattr;
 737         VALUE eval;
 738         SYM * esym;
 739
 740         // Alloc an IFENTRY
 741         if ((rif = f_ifent) == NULL)
 742                 rif = (IFENT *)malloc(sizeof(IFENT));
 743         else
 744                 f_ifent = rif->if_prev;
 745
 746         rif->if_prev = ifent;
 747         ifent = rif;
 748
 749         if (!disabled)
 750         {
 751                 if (expr(exprbuf, &eval, &eattr, &esym) != OK)
 752                         return 0;
 753
 754                 if ((eattr & DEFINED) == 0)
 755                         return error(undef_error);
 756
 757                 disabled = !eval;
 758         }
 759
 760         rif->if_state = (WORD)disabled;
 761         return 0;
 762 }
 763
 764
 765 //
 766 // .else, Do Alternate Case For .if
 767 //
 768 int d_else(void)
 769 {
 770         IFENT * rif = ifent;
 771
 772         if (rif->if_prev == NULL)
 773                 return error("mismatched .else");
 774
 775         if (disabled)
 776                 disabled = rif->if_prev->if_state;
 777         else
 778                 disabled = 1;
 779
 780         rif->if_state = (WORD)disabled;
 781         return 0;
 782 }
 783
 784
 785 //
 786 // .endif, End of conditional assembly block
 787 // This is also called by fpop() to pop levels of IFENTs in case a macro or
 788 // include file exits early with `exitm' or `end'.
 789 //
 790 int d_endif (void)
 791 {
 792         IFENT * rif = ifent;
 793
 794         if (rif->if_prev == NULL)
 795                 return error("mismatched .endif");
 796
 797         ifent = rif->if_prev;
 798         disabled = rif->if_prev->if_state;
 799         rif->if_prev = f_ifent;
 800         f_ifent = rif;
 801         return 0;
 802 }
 803