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 "risca.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 IFENT * ifent;                                  // Current ifent
  33 static IFENT ifent0;                    // Root ifent
  34 static IFENT * f_ifent;                 // Freelist of ifents
  35 static int disabled;                    // Assembly conditionally disabled
  36 int just_bss;                                   // 1, ds.b in microprocessor mode
  37 VALUE pcloc;                                    // Value of "PC" at beginning of line
  38 IFENT * ifent;                                  // Current ifent
  39 SYM * lab_sym;                                  // Label on line (or NULL)
  40
  41 char extra_stuff[] = "extra (unexpected) text found after addressing mode";
  42 char * comma_error = "missing comma";
  43 char * syntax_error = "syntax error";
  44 char * locgl_error = "cannot GLOBL local symbol";
  45 char * lab_ignored = "label ignored";
  46
  47 // Table to convert an addressing-mode number to a bitmask.
  48 LONG amsktab[0112] = {
  49         M_DREG, M_DREG, M_DREG, M_DREG,
  50         M_DREG, M_DREG, M_DREG, M_DREG,
  51
  52         M_AREG, M_AREG, M_AREG, M_AREG,
  53         M_AREG, M_AREG, M_AREG, M_AREG,
  54
  55         M_AIND, M_AIND, M_AIND, M_AIND,
  56         M_AIND, M_AIND, M_AIND, M_AIND,
  57
  58         M_APOSTINC, M_APOSTINC, M_APOSTINC, M_APOSTINC,
  59         M_APOSTINC, M_APOSTINC, M_APOSTINC, M_APOSTINC,
  60
  61         M_APREDEC, M_APREDEC, M_APREDEC, M_APREDEC,
  62         M_APREDEC, M_APREDEC, M_APREDEC, M_APREDEC,
  63
  64         M_ADISP, M_ADISP, M_ADISP, M_ADISP,
  65         M_ADISP, M_ADISP, M_ADISP, M_ADISP,
  66
  67         M_AINDEXED, M_AINDEXED, M_AINDEXED, M_AINDEXED,
  68         M_AINDEXED, M_AINDEXED, M_AINDEXED, M_AINDEXED,
  69
  70         M_ABSW,                                                                                 // 070
  71         M_ABSL,                                                                                 // 071
  72         M_PCDISP,                                                                               // 072
  73         M_PCINDEXED,                                                                    // 073
  74         M_IMMED,                                                                                // 074
  75         0L,                                                                                             // 075
  76         0L,                                                                                             // 076
  77         0L,                                                                                             // 077
  78         M_ABASE,                                                                                // 0100
  79         M_MEMPOST,                                                                              // 0101
  80         M_MEMPRE,                                                                               // 0102
  81         M_PCBASE,                                                                               // 0103
  82         M_PCMPOST,                                                                              // 0104
  83         M_PCMPRE,                                                                               // 0105
  84         M_AM_USP,                                                                               // 0106
  85         M_AM_SR,                                                                                // 0107
  86         M_AM_CCR,                                                                               // 0110
  87         M_AM_NONE                                                                               // 0111
  88 };                                                                                                      // 0112 length
  89
  90
  91 //
  92 // Initialize Line Processor
  93 //
  94 void init_procln(void)
  95 {
  96         disabled = 0;
  97         ifent = &ifent0;
  98         f_ifent = ifent0.if_prev = NULL;
  99         ifent0.if_state = 0;
 100 }
 101
 102
 103 //
 104 // Line Processor
 105 //
 106 void assemble(void)
 107 {
 108         int state;                                      // Keyword machine state (output)
 109         int j;                                          // Random int, must be fast
 110         char * p;                                       // Random char ptr, must be fast
 111         TOKEN * tk;                                     // First token in line
 112         char * label;                           // Symbol (or NULL)
 113         char * equate;                          // Symbol (or NULL)
 114         int labtyp = 0;                         // Label type (':', DCOLON)
 115         int equtyp = 0;                         // Equ type ('=', DEQUALS)
 116         VALUE eval;                                     // Expression value
 117         WORD eattr;                                     // Expression attributes
 118         SYM * esym;                                     // External symbol involved in expr.
 119         WORD siz = 0;                           // Size suffix to mnem/diretve/macro
 120         LONG amsk0, amsk1;                      // Address-type masks for ea0, ea1
 121         MNTAB * m;                                      // Code generation table pointer
 122         SYM * sy, * sy2;                        // Symbol (temp usage)
 123         char * opname = NULL;           // Name of dirctve/mnemonic/macro
 124         int listflag;                           // 0: Don't call listeol()
 125         int as68mode = 0;                       // 1: Handle multiple labels
 126         WORD rmask;                                     // Register list, for REG
 127         int registerbank;                       // RISC register bank
 128         int riscreg;                            // RISC register
 129
 130         listflag = 0;                           // Initialise listing flag
 131
 132 loop:                                                   // Line processing loop label
 133
 134         // Get another line of tokens
 135         if (tokln() == TKEOF)
 136         {
 137                 if (list_flag && listflag)                      // Flush last line of source
 138                         listeol();
 139
 140                 if (ifent->if_prev != NULL)                     // Check conditional token
 141                         error("hit EOF without finding matching .endif");
 142
 143                 return;
 144         }
 145
 146         DEBUG DumpTokenBuffer();
 147
 148         if (list_flag)
 149         {
 150                 if (listflag && listing > 0)
 151                         listeol();                                              // Tell listing generator about EOL
 152
 153                 lstout((char)(disabled ? '-' : lntag)); // Prepare new line for listing
 154                 listflag = 1;                                           // OK to call `listeol' now
 155                 just_bss = 0;                                           // Reset just_bss mode
 156         }
 157
 158         state = -3;                                                             // No keyword (just EOL)
 159         label = NULL;                                                   // No label
 160         lab_sym = NULL;                                                 // No (exported) label
 161         equate = NULL;                                                  // No equate
 162         tk = tok;                                                               // Save first token in line
 163         pcloc = (VALUE)sloc;                                    // Set beginning-of-line PC
 164
 165 loop1:                                                                          // Internal line processing loop
 166
 167         if (*tok == EOL)                                                // Restart loop if end-of-line
 168                 goto loop;
 169
 170         // First token MUST be a symbol
 171         if (*tok != SYMBOL)
 172         {
 173                 error(syntax_error);
 174                 goto loop;
 175         }
 176
 177         j = (int)tok[2];                                                // Skip equates (normal statements)
 178
 179         if (j == '=' || j == DEQUALS || j == SET || j == REG || j == EQUREG || j == CCDEF)
 180         {
 181                 equate = (char *)tok[1];
 182                 equtyp = j;
 183                 tok += 3;
 184                 goto normal;
 185         }
 186
 187         // Skip past label (but record it)
 188         if (j == ':' || j == DCOLON)
 189         {
 190 as68label:
 191                 label = (char *)tok[1];                         // Get label name
 192                 labtyp = tok[2];                                        // Get label type
 193                 tok += 3;                                                       // Go to next line token
 194
 195                 // Handle multiple labels; if there's another label, go process it,
 196                 // and come back at `as68label' above.
 197                 if (as68_flag)
 198                 {
 199                         as68mode = 0;
 200
 201                         if (*tok == SYMBOL && tok[2] == ':')
 202                         {
 203                                 as68mode = 1;
 204                                 goto do_label;
 205                         }
 206                 }
 207         }
 208
 209         if (*tok == EOL)                                                // EOL is legal here...
 210                 goto normal;
 211
 212         // Next token MUST be a symbol
 213         if (*tok++ != SYMBOL)
 214         {
 215                 error(syntax_error);
 216                 goto loop;
 217         }
 218
 219 // This is the problem here: On 64-bit platforms, this cuts the native pointer
 220 // in half. We need to figure out how to fix this.
 221 #warning "!!! Bad pointer !!!"
 222         opname = p = (char *)*tok++;                    // Store opcode name here
 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                                 if (label != NULL)
 300                                         warn(lab_ignored);
 301
 302                                 defmac();
 303                         }
 304
 305                         goto loop;
 306                 case MN_EXITM:                                          // .exitm --- exit macro
 307                 case MN_ENDM:                                           // .endm --- same as .exitm
 308                         if (!disabled)
 309                         {
 310                                 if (label != NULL)
 311                                         warn(lab_ignored);
 312
 313                                 exitmac();
 314                         }
 315
 316                         goto loop;
 317                 case MN_REPT:
 318                         if (!disabled)
 319                         {
 320                                 if (label != NULL)
 321                                         warn(lab_ignored);
 322
 323                                 defrept();
 324                         }
 325
 326                         goto loop;
 327                 case MN_ENDR:
 328                         if (!disabled)
 329                                 error("mis-nested .endr");
 330
 331                         goto loop;
 332                 }
 333         }
 334
 335 normal:
 336         if (disabled)                                                   // Conditionally disabled code
 337                 goto loop;
 338
 339         // Do equates
 340         if (equate != NULL)
 341         {
 342                 j = 0;                                                          // Pick global or local sym enviroment
 343
 344                 if (*equate == '.')
 345                         j = curenv;
 346
 347                 sy = lookup(equate, LABEL, j);
 348
 349                 if (sy == NULL)
 350                 {
 351                         sy = newsym(equate, LABEL, j);
 352                         sy->sattr = 0;
 353
 354                         if (equtyp == DEQUALS)
 355                         {
 356                                 // Can't GLOBAL a local symbol
 357                                 if (j)
 358                                 {
 359                                         error(locgl_error);
 360                                         goto loop;
 361                                 }
 362
 363                                 sy->sattr = GLOBAL;
 364                         }
 365                 }
 366                 else if ((sy->sattr & DEFINED) && equtyp != SET)
 367                 {
 368                         if ((equtyp == EQUREG) && (sy->sattre & UNDEF_EQUR))
 369                         {
 370                                 sy->sattre |= ~UNDEF_EQUR;
 371                                 sy->svalue  = 0;
 372                         }
 373                         else if ((equtyp == CCDEF) && (sy->sattre & UNDEF_CC))
 374                         {
 375                                 sy->sattre |= ~UNDEF_CC;
 376                                 sy->svalue = 0;
 377                         }
 378                         else
 379                         {
 380                                 errors("multiple equate to '%s'", sy->sname);
 381                                 goto loop;
 382                         }
 383                 }
 384
 385                 // Put symbol in "order of definition" list
 386                 if (!(sy->sattr & SDECLLIST))
 387                         sym_decl(sy);
 388
 389                 // Parse value to equate symbol to;
 390                 // o  .equr
 391                 // o  .reg
 392                 // o  everything else
 393                 if (equtyp == EQUREG)
 394                 {
 395                         // Check that we are in a RISC section
 396                         if (!rgpu && !rdsp)
 397                         {
 398                                 error(".equr/.regequ must be defined in .gpu/.dsp section");
 399                                 goto loop;
 400                         }
 401
 402                         // Check for register to equate to
 403                         if ((*tok >= KW_R0) && (*tok <= KW_R31))
 404                         {
 405                                 sy->sattre  = EQUATEDREG | RISCSYM;     // Mark as equated register
 406                                 riscreg = (*tok - KW_R0);
 407                                 sy->sattre |= (riscreg << 8);           // Store register number
 408
 409                                 if ((tok[1] == ',') && (tok[2] == CONST))
 410                                 {
 411                                         tok += 3;
 412
 413                                         if (*tok == 0)
 414                                                 registerbank = BANK_0;
 415                                         else if (*tok == 1)
 416                                                 registerbank = BANK_1;
 417                                         else
 418                                                 registerbank = BANK_N;
 419                                 }
 420                                 else
 421                                 {
 422                                         registerbank = BANK_N;
 423                                 }
 424
 425                                 sy->sattre |= regbank;          // Store register bank
 426                                 eattr = ABS | DEFINED | GLOBAL;
 427                                 eval = 0x80000080 + (riscreg) + (registerbank << 8);
 428                                 tok++;
 429                         }
 430                         // Checking for a register symbol
 431                         else if (tok[0] == SYMBOL)
 432                         {
 433                                 sy2 = lookup((char *)tok[1], LABEL, j);
 434
 435                                 // Make sure symbol is a valid equreg
 436                                 if (!sy2 || !(sy2->sattre & EQUATEDREG))
 437                                 {
 438                                         error("invalid GPU/DSP .equr/.regequ definition");
 439                                         goto loop;
 440                                 }
 441                                 else
 442                                 {
 443                                         eattr = ABS | DEFINED | GLOBAL; // Copy symbols attributes
 444                                         sy->sattre = sy2->sattre;
 445                                         eval = (sy2->svalue & 0xFFFFF0FF);
 446                                         tok += 2;
 447                                 }
 448                         }
 449                         else
 450                         {
 451                                 error("invalid GPU/DSP .equr/.regequ definition");
 452                                 goto loop;
 453                         }
 454                 }
 455                 else if (equtyp == REG)
 456                 {
 457                         if (reglist(&rmask) < 0)
 458                                 goto loop;
 459
 460                         eval = (VALUE)rmask;
 461                         eattr = ABS | DEFINED;
 462                 }
 463                 else if (equtyp == CCDEF)
 464                 {
 465                         sy->sattre |= EQUATEDCC;
 466                         eattr = ABS | DEFINED | GLOBAL;
 467
 468                         if (tok[0] == SYMBOL)
 469                         {
 470                                 sy2 = lookup((char *)tok[1], LABEL, j);
 471
 472                                 if (!sy2 || !(sy2->sattre & EQUATEDCC))
 473                                 {
 474                                         error("invalid gpu/dsp .ccdef definition");
 475                                         goto loop;
 476                                 }
 477                                 else
 478                                 {
 479                                         eattr = ABS | DEFINED | GLOBAL;
 480                                         sy->sattre = sy2->sattre;
 481                                         eval = sy2->svalue;
 482                                         tok += 2;
 483                                 }
 484                         }
 485                         else if (expr(exprbuf, &eval, &eattr, &esym) != OK)
 486                                 goto loop;
 487                 }
 488                 //equ a equr
 489                 else if (*tok == SYMBOL)
 490                 {
 491                         sy2 = lookup((char *)tok[1], LABEL, j);
 492
 493                         if (sy2 && (sy2->sattre & EQUATEDREG))
 494                         {
 495                                 sy->stype = sy2->stype;
 496                                 sy->sattr = sy2->sattr;
 497                                 sy->sattre = sy2->sattre;
 498                                 sy->svalue = (sy2->svalue & 0xFFFFF0FF);
 499                                 goto loop;
 500                         }
 501                         else if (expr(exprbuf, &eval, &eattr, &esym) != OK)
 502                                 goto loop;
 503                 }
 504                 else if (expr(exprbuf, &eval, &eattr, &esym) != OK)
 505                         goto loop;
 506
 507                 if (!(eattr & DEFINED))
 508                 {
 509                         error(undef_error);
 510                         goto loop;
 511                 }
 512
 513                 sy->sattr |= eattr | EQUATED;           // Symbol inherits value and attributes
 514                 sy->svalue = eval;
 515
 516                 if (list_flag)                                          // Put value in listing
 517                         listvalue(eval);
 518
 519                 at_eol();                                                       // Must be at EOL now
 520                 goto loop;
 521         }
 522
 523         // Do labels
 524         if (label != NULL)
 525         {
 526 do_label:
 527                 j = 0;
 528
 529                 if (*label == '.')
 530                         j = curenv;
 531
 532                 sy = lookup(label, LABEL, j);
 533
 534                 if (sy == NULL)
 535                 {
 536                         sy = newsym(label, LABEL, j);
 537                         sy->sattr = 0;
 538                         sy->sattre = RISCSYM;
 539                 }
 540                 else if (sy->sattr & DEFINED)
 541                 {
 542                         errors("multiply-defined label '%s'", label);
 543                         goto loop;
 544                 }
 545
 546                 // Put symbol in "order of definition" list
 547                 if (!(sy->sattr & SDECLLIST))
 548                         sym_decl(sy);
 549
 550                 if (orgactive)
 551                 {
 552                         sy->svalue = orgaddr;
 553                         sy->sattr |= ABS | DEFINED | EQUATED;
 554                 }
 555                 else
 556                 {
 557                         sy->svalue = sloc;
 558                         sy->sattr |= DEFINED | cursect;
 559                 }
 560
 561                 lab_sym = sy;
 562
 563                 if (!j)
 564                         ++curenv;
 565
 566                 // Make label global
 567                 if (labtyp == DCOLON)
 568                 {
 569                         if (j)
 570                         {
 571                                 error(locgl_error);
 572                                 goto loop;
 573                         }
 574
 575                         sy->sattr |= GLOBAL;
 576                 }
 577
 578                 // If we're in as68 mode, and there's another label, go back and handle it
 579                 if (as68_flag && as68mode)
 580                         goto as68label;
 581         }
 582
 583         // Punt on EOL
 584         if (state == -3)
 585                 goto loop;
 586
 587         // If we are in GPU or DSP mode and still in need of a mnemonic then search
 588         // for one
 589         if ((rgpu || rdsp) && (state < 0 || state >= 1000))
 590         {
 591                 for(state=0, p=opname; state>=0;)
 592                 {
 593                         j = mrbase[state] + (int)tolowertab[*p];
 594
 595                         // Reject, character doesn't match
 596                         if (mrcheck[j] != state)
 597                         {
 598                                 state = -1;                                     // No match
 599                                 break;
 600                         }
 601
 602                         // Must accept or reject at EOS
 603                         if (!*++p)
 604                         {
 605                                 state = mraccept[j];            // (-1 on no terminal match)
 606                                 break;
 607                         }
 608
 609                         state = mrtab[j];
 610                 }
 611
 612                 // Call RISC code generator if we found a mnemonic
 613                 if (state >= 3000)
 614                 {
 615                         risccg(state);
 616                         goto loop;
 617                 }
 618         }
 619
 620         // Invoke macro or complain about bad mnemonic
 621         if (state < 0)
 622         {
 623                 if ((sy = lookup(opname, MACRO, 0)) != NULL)
 624                         invokemac(sy, siz);
 625                 else
 626                         errors("unknown op '%s'", opname);
 627
 628                 goto loop;
 629         }
 630
 631         // Call directive handlers
 632         if (state < 500)
 633         {
 634                 (*dirtab[state])(siz);
 635                 goto loop;
 636         }
 637
 638         // Do mnemonics
 639         // o  can't deposit instrs in BSS or ABS
 640         // o  do automatic .EVEN for instrs
 641         // o  allocate space for largest possible instr
 642         // o  can't do ".b" operations with an address register
 643         if (scattr & SBSS)
 644         {
 645                 error("cannot initialize non-storage (BSS) section");
 646                 goto loop;
 647         }
 648
 649         if (sloc & 1)                                                   // Automatic .even
 650                 auto_even();
 651
 652         if (challoc - ch_size < 18)                             // Make sure have space in current chunk
 653                 chcheck(0);
 654
 655         m = &machtab[state - 1000];
 656
 657         // Call special-mode handler
 658         if (m->mnattr & CGSPECIAL)
 659         {
 660                 (*m->mnfunc)(m->mninst, siz);
 661                 goto loop;
 662         }
 663
 664         if (amode(1) < 0)                                               // Parse 0, 1 or 2 addr modes
 665                 goto loop;
 666
 667         if (*tok != EOL)
 668                 error(extra_stuff);
 669
 670         amsk0 = amsktab[am0];
 671         amsk1 = amsktab[am1];
 672
 673         // Catch attempts to use ".B" with an address register (yes, this check
 674         // does work at this level)
 675         if (siz == SIZB && (am0 == AREG || am1 == AREG))
 676         {
 677                 error("cannot use '.b' with an address register");
 678                 goto loop;
 679         }
 680
 681         for(;;)
 682         {
 683                 if ((m->mnattr & siz) && (amsk0 & m->mn0) != 0 && (amsk1 & m->mn1) != 0)
 684                 {
 685                         (*m->mnfunc)(m->mninst, siz);
 686                         goto loop;
 687                 }
 688
 689                 m = &machtab[m->mncont];
 690         }
 691 }
 692
 693
 694 //
 695 // .if, Start Conditional Assembly
 696 //
 697 int d_if(void)
 698 {
 699         IFENT * rif;
 700         WORD eattr;
 701         VALUE eval;
 702         SYM * esym;
 703
 704         // Alloc an IFENTRY
 705         if ((rif = f_ifent) == NULL)
 706 //              rif = (IFENT *)amem((LONG)sizeof(IFENT));
 707                 rif = (IFENT *)malloc(sizeof(IFENT));
 708         else
 709                 f_ifent = rif->if_prev;
 710
 711         rif->if_prev = ifent;
 712         ifent = rif;
 713
 714         if (!disabled)
 715         {
 716                 if (expr(exprbuf, &eval, &eattr, &esym) != OK) return 0;
 717
 718                 if ((eattr & DEFINED) == 0)
 719                         return error(undef_error);
 720
 721                 disabled = !eval;
 722         }
 723
 724         rif->if_state = (WORD)disabled;
 725         return 0;
 726 }
 727
 728
 729 //
 730 // .else, Do Alternate Case For .if
 731 //
 732 int d_else(void)
 733 {
 734         IFENT * rif = ifent;
 735
 736         if (rif->if_prev == NULL)
 737                 return error("mismatched .else");
 738
 739         if (disabled)
 740                 disabled = rif->if_prev->if_state;
 741         else
 742                 disabled = 1;
 743
 744         rif->if_state = (WORD)disabled;
 745         return 0;
 746 }
 747
 748
 749 //
 750 // .endif, End of conditional assembly block
 751 // This is also called by fpop() to pop levels of IFENTs in case a macro or
 752 // include file exits early with `exitm' or `end'.
 753 //
 754 int d_endif (void)
 755 {
 756         IFENT * rif = ifent;
 757
 758         if (rif->if_prev == NULL)
 759                 return error("mismatched .endif");
 760
 761         ifent = rif->if_prev;
 762         disabled = rif->if_prev->if_state;
 763         rif->if_prev = f_ifent;
 764         f_ifent = rif;
 765         return 0;
 766 }