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

   1 //
   2 // RMAC - Reboot's Macro Assembler for the Atari Jaguar Console System
   3 // SECT.C - Code Generation, Fixups and Section Management
   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 "sect.h"
  10 #include "direct.h"
  11 #include "error.h"
  12 #include "expr.h"
  13 #include "listing.h"
  14 #include "mach.h"
  15 #include "mark.h"
  16 #include "risca.h"
  17 #include "symbol.h"
  18 #include "token.h"
  19
  20 // Section descriptors
  21 SECT sect[NSECTS];                                              // All sections...
  22 int cursect;                                                    // Current section number
  23
  24 // These are copied from the section descriptor, the current code chunk
  25 // descriptor and the current fixup chunk descriptor when a switch is made into
  26 // a section.  They are copied back to the descriptors when the section is left.
  27 WORD scattr;                                                    // Section attributes
  28 LONG sloc;                                                              // Current loc in section
  29
  30 CHUNK * scode;                                                  // Current (last) code chunk
  31 LONG challoc;                                                   // # bytes alloc'd to code chunk
  32 LONG ch_size;                                                   // # bytes used in code chunk
  33 char * chptr;                                                   // Deposit point in code chunk buffer
  34
  35 CHUNK * sfix;                                                   // Current (last) fixup chunk
  36 LONG fchalloc;                                                  // # bytes alloc'd to fixup chunk
  37 LONG fchsize;                                                   // # bytes used in fixup chunk
  38 PTR fchptr;                                                             // Deposit point in fixup chunk buffer
  39
  40 unsigned fwdjump[MAXFWDJUMPS];                  // forward jump check table
  41 unsigned fwindex = 0;                                   // forward jump index
  42
  43 // Return a size (SIZB, SIZW, SIZL) or 0, depending on what kind of fixup is
  44 // associated with a location.
  45 static char fusiztab[] = {
  46    0,                                           // FU_QUICK
  47    1,                                           // FU_BYTE
  48    2,                                           // FU_WORD
  49    2,                                           // FU_WBYTE
  50    4,                                           // FU_LONG
  51    1,                                           // FU_BBRA
  52    0,                                           // (unused)
  53    1,                                           // FU_6BRA
  54 };
  55
  56 // Offset to REAL fixup location
  57 static char fusizoffs[] = {
  58    0,                                           // FU_QUICK
  59    0,                                           // FU_BYTE
  60    0,                                           // FU_WORD
  61    1,                                           // FU_WBYTE
  62    0,                                           // FU_LONG
  63    1,                                           // FU_BBRA
  64    0,                                           // (unused)
  65    0,                                           // FU_6BRA
  66 };
  67
  68
  69 //
  70 // Make a New (Clean) Section
  71 //
  72 void mksect(int sno, WORD attr)
  73 {
  74         SECT * p = &sect[sno];
  75         p->scattr = attr;
  76         p->sloc = 0;
  77         p->scode = p->sfcode = NULL;
  78         p->sfix = p->sffix = NULL;
  79 }
  80
  81
  82 //
  83 // Switch to Another Section (Copy Section & Chunk Descriptors to Global Vars
  84 // for Fast Access)
  85 //
  86 void switchsect(int sno)
  87 {
  88         CHUNK * cp;                                                             // Chunk pointer
  89         cursect = sno;
  90         SECT * p = &sect[sno];
  91
  92         scattr = p->scattr;                                             // Copy section vars
  93         sloc = p->sloc;
  94         scode = p->scode;
  95         sfix = p->sfix;
  96
  97         // Copy code chunk vars
  98         if ((cp = scode) != NULL)
  99         {
 100                 challoc = cp->challoc;
 101                 ch_size = cp->ch_size;
 102                 chptr = cp->chptr + ch_size;
 103         }
 104         else
 105                 challoc = ch_size = 0;
 106
 107         // Copy fixup chunk vars
 108         if ((cp = sfix) != NULL)
 109         {
 110                 fchalloc = cp->challoc;
 111                 fchsize = cp->ch_size;
 112                 fchptr.cp = cp->chptr + fchsize;
 113         }
 114         else
 115                 fchalloc = fchsize = 0;
 116 }
 117
 118
 119 //
 120 // Save Current Section
 121 //
 122 void savsect(void)
 123 {
 124         SECT * p = &sect[cursect];
 125
 126         p->scattr = scattr;                                             // Bailout section vars
 127         p->sloc = sloc;
 128
 129         if (scode != NULL)                                              // Bailout code chunk
 130                 scode->ch_size = ch_size;
 131
 132         if (sfix != NULL)                                               // Bailout fixup chunk
 133                 sfix->ch_size = fchsize;
 134 }
 135
 136
 137 //
 138 // Initialize Sections; Setup initial ABS, TEXT, DATA and BSS sections
 139 //
 140 void init_sect(void)
 141 {
 142         int i;
 143
 144         // Cleanup all sections
 145         for(i=0; i<NSECTS; i++)
 146                 mksect(i, 0);
 147
 148         // Construct default sections, make TEXT the current section
 149         mksect(ABS,   SUSED | SABS | SBSS);             // ABS
 150         mksect(TEXT,  SUSED | TEXT       );             // TEXT
 151         mksect(DATA,  SUSED | DATA       );             // DATA
 152         mksect(BSS,   SUSED | BSS | SBSS );             // BSS
 153 //      mksect(M6502, SUSED | TEXT       );             // 6502 code section
 154
 155         switchsect(TEXT);                                               // Switch to TEXT for starters
 156 }
 157
 158
 159 //
 160 // Test to see if a location has a fixup sic'd on it.  This is used by the
 161 // listing generator to print 'xx's instead of '00's for forward references
 162 //
 163 int fixtest(int sno, LONG loc)
 164 {
 165         CHUNK * ch;
 166         PTR fup;
 167         char * fuend;
 168         WORD w;
 169         LONG xloc;
 170
 171         stopmark();                                                             // Force update to sect[] variables
 172
 173         // Hairy, ugly linear search for a mark on our location;
 174         // the speed doesn't matter, since this is only done when generating a
 175         // listing, which is SLOW.
 176         for(ch=sect[sno].sffix; ch!=NULL; ch=ch->chnext)
 177         {
 178                 fup.cp = (char *)ch->chptr;
 179                 fuend = fup.cp + ch->ch_size;
 180
 181                 while (fup.cp < fuend)
 182                 {
 183                         w = *fup.wp++;
 184                         xloc = *fup.lp++ + (int)fusizoffs[w & FUMASK];
 185                         fup.wp += 2;
 186
 187                         if (xloc == loc)
 188                                 return (int)fusiztab[w & FUMASK];
 189
 190                         if (w & FU_EXPR)
 191                         {
 192                                 w = *fup.wp++;
 193                                 fup.lp += w;
 194                         }
 195                         else
 196                                 ++fup.lp;
 197                 }
 198         }
 199
 200         return 0;
 201 }
 202
 203
 204 //
 205 // Check that there are at least `amt' bytes left in the current chunk. If
 206 // there are not, allocate another chunk of at least `amt' bytes (and probably
 207 // more).
 208 //
 209 // If `amt' is zero, ensure there are at least CH_THRESHOLD bytes, likewise.
 210 //
 211 int chcheck(LONG amt)
 212 {
 213         // If in BSS section, no allocation required
 214         if (scattr & SBSS)
 215                 return 0;
 216
 217         if (!amt)
 218                 amt = CH_THRESHOLD;
 219
 220         if ((int)(challoc - ch_size) >= (int)amt)
 221                 return 0;
 222
 223         if (amt < CH_CODE_SIZE)
 224                 amt = CH_CODE_SIZE;
 225
 226         SECT * p = &sect[cursect];
 227         CHUNK * cp = malloc(sizeof(CHUNK) + amt);
 228
 229         // First chunk in section
 230         if (scode == NULL)
 231         {
 232                 cp->chprev = NULL;
 233                 p->sfcode = cp;
 234         }
 235         // Add chunk to other chunks
 236         else
 237         {
 238                 cp->chprev = scode;
 239                 scode->chnext = cp;
 240                 scode->ch_size = ch_size;                       // Save old chunk's globals
 241         }
 242
 243         // Setup chunk and global vars
 244         cp->chloc = sloc;
 245         cp->chnext = NULL;
 246         challoc = cp->challoc = amt;
 247         ch_size = cp->ch_size = 0;
 248         chptr = cp->chptr = ((char *)cp) + sizeof(CHUNK);
 249         scode = p->scode = cp;
 250
 251         return 0;
 252 }
 253
 254
 255 // This is really wrong. We need to make some proper structures here so we don't
 256 // have to count sizes of objects, that's what the compiler's for! :-P
 257 #define FIXUP_BASE_SIZE (sizeof(WORD) + sizeof(LONG) + sizeof(WORD) + sizeof(WORD))
 258 //
 259 // Arrange for a fixup on a location
 260 //
 261 int fixup(WORD attr, LONG loc, TOKEN * fexpr)
 262 {
 263         LONG i;
 264         LONG len = 0;
 265         CHUNK * cp;
 266         SECT * p;
 267         // Shamus: Expression lengths are voodoo ATM (varibale "i"). Need to fix this.
 268         DEBUG printf("FIXUP@$%X: $%X\n", loc, attr);
 269
 270         // Compute length of expression (could be faster); determine if it's the
 271         // single-symbol case; no expression if it's just a mark. This code assumes
 272         // 16 bit WORDs and 32 bit LONGs
 273         if (*fexpr == SYMBOL && fexpr[2] == ENDEXPR)
 274         {
 275                 // Just a single symbol
 276                 // SCPCD : correct bit mask for attr (else other FU_xxx will match) NYAN !
 277                 if ((attr & 0x0F00) == FU_JR)
 278                 {
 279 //                      i = 18;
 280 //                      i = FIXUP_BASE_SIZE + (sizeof(LONG) * 2);
 281                         i = FIXUP_BASE_SIZE + sizeof(SYM *) + sizeof(LONG);
 282                 }
 283                 else
 284                 {
 285 //                      i = 14;
 286                         i = FIXUP_BASE_SIZE + sizeof(SYM *);
 287                 }
 288         }
 289         else
 290         {
 291                 attr |= FU_EXPR;
 292
 293                 for(len=0; fexpr[len]!=ENDEXPR; len++)
 294                 {
 295                         if (fexpr[len] == CONST || fexpr[len] == SYMBOL)
 296                                 len++;
 297                 }
 298
 299                 len++;                                                          // Add 1 for ENDEXPR
 300 //              i = (len << 2) + 12;
 301                 i = FIXUP_BASE_SIZE + sizeof(WORD) + (len * sizeof(TOKEN));
 302         }
 303
 304         // Maybe alloc another fixup chunk for this one to fit in
 305         if ((fchalloc - fchsize) < i)
 306         {
 307                 p = &sect[cursect];
 308                 cp = (CHUNK *)malloc(sizeof(CHUNK) + CH_FIXUP_SIZE);
 309
 310                 // First fixup chunk in section
 311                 if (sfix == NULL)
 312                 {
 313                         cp->chprev = NULL;
 314                         p->sffix = cp;
 315                 }
 316                 // Add to other chunks
 317                 else
 318                 {
 319                         cp->chprev = sfix;
 320                         sfix->chnext = cp;
 321                         sfix->ch_size = fchsize;
 322                 }
 323
 324                 // Setup fixup chunk and its global vars
 325                 cp->chnext = NULL;
 326                 fchalloc = cp->challoc = CH_FIXUP_SIZE;
 327                 fchsize = cp->ch_size = 0;
 328                 fchptr.cp = cp->chptr = ((char *)cp) + sizeof(CHUNK);
 329                 sfix = p->sfix = cp;
 330         }
 331
 332         // Record fixup type, fixup location, and the file number and line number
 333         // the fixup is located at.
 334         *fchptr.wp++ = attr;
 335         *fchptr.lp++ = loc;
 336         *fchptr.wp++ = cfileno;
 337         *fchptr.wp++ = (WORD)curlineno;
 338
 339         // Store postfix expression or pointer to a single symbol, or nothing for a
 340         // mark.
 341         if (attr & FU_EXPR)
 342         {
 343                 *fchptr.wp++ = (WORD)len;
 344
 345                 while (len--)
 346                         *fchptr.lp++ = (LONG)*fexpr++;
 347         }
 348         else
 349         {
 350 //              *fchptr.lp++ = (LONG)fexpr[1];
 351                 *fchptr.sy++ = symbolPtr[fexpr[1]];
 352         }
 353
 354         // SCPCD : correct bit mask for attr (else other FU_xxx will match) NYAN !
 355         if ((attr & 0x0F00) == FU_JR)
 356         {
 357                 if (orgactive)
 358                         *fchptr.lp++ = orgaddr;
 359                 else
 360                         *fchptr.lp++ = 0x00000000;
 361         }
 362
 363         fchsize += i;
 364         return 0;
 365 }
 366
 367
 368 //
 369 // Resolve all Fixups
 370 //
 371 int ResolveAllFixups(void)
 372 {
 373         unsigned i;
 374         char buf[EBUFSIZ];
 375
 376         // Make undefined symbols GLOBL
 377         if (glob_flag)
 378                 syg_fix();
 379
 380         DEBUG printf("Resolving TEXT sections...\n");
 381         ResolveFixups(TEXT);
 382         DEBUG printf("Resolving DATA sections...\n");
 383         ResolveFixups(DATA);
 384
 385         // We need to do a final check of forward 'jump' destination addresses that
 386         // are external
 387         for(i=0; i<MAXFWDJUMPS; i++)
 388         {
 389                 if (fwdjump[i])
 390                 {
 391                         err_setup();
 392                         sprintf(buf, "* \'jump\' at $%08X - destination address is external to this source file and cannot have its aligment validated", fwdjump[i]);
 393
 394                         if (listing > 0)
 395                                 ship_ln(buf);
 396
 397                         if (err_flag)
 398                                 write(err_fd, buf, (LONG)strlen(buf));
 399                         else
 400                                 printf("%s\n", buf);
 401                 }
 402         }
 403
 404         return 0;
 405 }
 406
 407
 408 //
 409 // Resolve Fixups in a Section
 410 //
 411 int ResolveFixups(int sno)
 412 {
 413         PTR fup;                                        // Current fixup
 414         WORD * fuend;                           // End of last fixup (in this chunk)
 415         WORD w;                                         // Fixup word (type+modes+flags)
 416         char * locp;                            // Location to fix (in cached chunk)
 417         LONG loc;                                       // Location to fixup
 418         VALUE eval;                                     // Expression value
 419         WORD eattr;                                     // Expression attrib
 420         SYM * esym;                                     // External symbol involved in expr
 421         SYM * sy;                                       // (Temp) pointer to a symbol
 422         WORD i;                                         // (Temp) word
 423         WORD tdb;                                       // eattr & TDB
 424         LONG oaddr;
 425         int reg2;
 426         WORD flags;
 427         unsigned page_jump = 0;
 428         unsigned address = 0;
 429         unsigned j;
 430         char buf[EBUFSIZ];
 431
 432         SECT * sc = &sect[sno];
 433         CHUNK * ch = sc->sffix;
 434
 435         if (ch == NULL)
 436                 return 0;
 437
 438         CHUNK * cch = sc->sfcode;                               // "cache" first chunk
 439
 440         if (cch == NULL)                                                // Can't fixup a sect with nothing in it
 441                 return 0;
 442
 443         do
 444         {
 445                 fup.cp = ch->chptr;                                     // fup -> start of chunk
 446                 fuend = (WORD *)(fup.cp + ch->ch_size); // fuend -> end of chunk
 447
 448                 while (fup.wp < fuend)
 449                 {
 450                         w = *fup.wp++;
 451                         loc = *fup.lp++;
 452                         cfileno = *fup.wp++;
 453                         curlineno = (int)*fup.wp++;
 454
 455                         esym = NULL;
 456
 457                         // Search for chunk containing location to fix up; compute a
 458                         // pointer to the location (in the chunk). Often we will find the
 459                         // fixup is in the "cached" chunk, so the linear-search is seldom
 460                         // executed.
 461                         if (loc < cch->chloc || loc >= (cch->chloc + cch->ch_size))
 462                         {
 463                                 for(cch=sc->sfcode; cch!=NULL; cch=cch->chnext)
 464                                 {
 465                                         if (loc >= cch->chloc && loc < (cch->chloc + cch->ch_size))
 466                                                 break;
 467                                 }
 468
 469                                 if (cch == NULL)
 470                                 {
 471                                         interror(7);                    // Fixup (loc) out of range
 472                                         // NOTREACHED
 473                                 }
 474                         }
 475
 476                         locp = cch->chptr + (loc - cch->chloc);
 477                         eattr = 0;
 478
 479                         // Compute expression/symbol value and attribs
 480                         // Complex expression
 481                         if (w & FU_EXPR)
 482                         {
 483                                 i = *fup.wp++;
 484
 485                                 if (evexpr(fup.tk, &eval, &eattr, &esym) != OK)
 486                                 {
 487                                         fup.lp += i;
 488                                         continue;
 489                                 }
 490
 491                                 fup.lp += i;
 492                         }
 493                         // Simple symbol
 494                         else
 495                         {
 496                                 sy = *fup.sy++;
 497                                 eattr = sy->sattr;
 498
 499                                 if (eattr & DEFINED)
 500                                         eval = sy->svalue;
 501                                 else
 502                                         eval = 0;
 503
 504                                 if ((eattr & (GLOBAL | DEFINED)) == GLOBAL)
 505                                         esym = sy;
 506                         }
 507
 508                         tdb = (WORD)(eattr & TDB);
 509
 510                         // If the expression is undefined and no external symbol is
 511                         // involved, then it's an error.
 512                         if (!(eattr & DEFINED) && esym == NULL)
 513                         {
 514                                 error(undef_error);
 515                                 continue;
 516                         }
 517
 518                         if (((w & 0x0F00) == FU_MOVEI) && esym)
 519                                 esym->sattre |= RISCSYM;
 520
 521                         // Do the fixup
 522                         //
 523                         // If a PC-relative fixup is undefined, its value is *not*
 524                         // subtracted from the location (that will happen in the linker
 525                         // when the external reference is resolved).
 526                         //
 527                         // MWC expects PC-relative things to have the LOC subtracted from
 528                         // the value, if the value is external (that is, undefined at this
 529                         // point).
 530                         //
 531                         // PC-relative fixups must be DEFINED and either in the same
 532                         // section (whereupon the subtraction takes place) or ABS (with no
 533                         // subtract).
 534                         if (w & FU_PCREL)
 535                         {
 536                                 if (eattr & DEFINED)
 537                                 {
 538                                         if (tdb == sno)
 539                                                 eval -= (VALUE)loc;
 540                                         else if (tdb)
 541                                         {
 542                                                 error("PC-relative expr across sections");
 543                                                 continue;
 544                                         }
 545
 546                                         if (sbra_flag && (w & FU_LBRA) && (eval + 0x80 < 0x100))
 547                                                 warn("unoptimized short branch");
 548                                 }
 549                                 else if (obj_format == MWC)
 550                                         eval -= (VALUE)loc;
 551
 552                                 tdb = 0;
 553                                 eattr &= ~TDB;
 554                         }
 555
 556                         // Do fixup classes
 557                         switch ((int)(w & FUMASK))
 558                         {
 559                         // FU_BBRA fixes up a one-byte branch offset.
 560                         case FU_BBRA:
 561                                 if (!(eattr & DEFINED))
 562                                 {
 563                                         error("external short branch");
 564                                         continue;
 565                                 }
 566
 567                                 eval -= 2;
 568
 569                                 if (eval + 0x80 >= 0x100)
 570                                         goto range;
 571
 572                                 if (eval == 0)
 573                                 {
 574                                         error("illegal bra.s with zero offset");
 575                                         continue;
 576                                 }
 577
 578                                 *++locp = (char)eval;
 579                                 break;
 580                         // Fixup one-byte value at locp + 1.
 581                         case FU_WBYTE:
 582                                 ++locp;
 583                                 // FALLTHROUGH
 584                         // Fixup one-byte forward references
 585                         case FU_BYTE:
 586                                 if (!(eattr & DEFINED))
 587                                 {
 588                                         error("external byte reference");
 589                                         continue;
 590                                 }
 591
 592                                 if (tdb)
 593                                 {
 594                                         error("non-absolute byte reference");
 595                                         continue;
 596                                 }
 597
 598                                 if ((w & FU_PCREL) && eval + 0x80 >= 0x100)
 599                                         goto range;
 600
 601                                 if (w & FU_SEXT)
 602                                 {
 603                                         if (eval + 0x100 >= 0x200)
 604                                                 goto range;
 605                                 }
 606                                 else if (eval >= 0x100)
 607                                         goto range;
 608
 609                                 *locp = (char)eval;
 610                                 break;
 611                         // Fixup WORD forward references;
 612                         // the word could be unaligned in the section buffer, so we have to
 613                         // be careful.
 614                         case FU_WORD:
 615                                 if (((w & 0x0F00) == FU_JR) || ((w & 0x0F00) == FU_MJR))
 616                                 {
 617                                         oaddr = *fup.lp++;
 618
 619                                         if (oaddr)
 620                                         {
 621                                                 reg2 = (signed)((eval - (oaddr + 2)) / 2);// & 0x1F;
 622                                         }
 623                                         else
 624                                         {
 625                                                 reg2 = (signed)((eval - (loc + 2)) / 2);// & 0x1F;
 626                                         }
 627
 628                                         if ((w & 0x0F00) == FU_MJR)
 629                                         {
 630                                                 // Main code destination alignment checking here for
 631                                                 // forward declared labels
 632                                                 address = (oaddr) ? oaddr : loc;
 633
 634                                                 if (((address >= 0xF03000) && (address < 0xF04000)
 635                                                         && (eval < 0xF03000)) || ((eval >= 0xF03000)
 636                                                         && (eval < 0xF04000) && (address < 0xF03000)))
 637                                                 {
 638                                                         warni("* \'jr\' at $%08X - cannot jump relative between "
 639                                                                 "main memory and local gpu ram", address);
 640                                                 }
 641                                                 else
 642                                                 {
 643                                                         page_jump = (address & 0xFFFFFF00) - (eval & 0xFFFFFF00);
 644
 645                                                         if (page_jump)
 646                                                         {
 647                                                                 // This jump is to a page outside of the
 648                                                                 // current 256 byte page
 649                                                                 if (eval % 4)
 650                                                                 {
 651                                                                         warni("* \'jr\' at $%08X - destination address not aligned for long page jump, insert a \'nop\' before the destination address", address);
 652                                                                 }
 653                                                         }
 654                                                         else
 655                                                         {
 656                                                                 // This jump is in the current 256 byte page
 657                                                                 if ((eval - 2) % 4)
 658                                                                 {
 659                                                                         warni("* \'jr\' at $%08X - destination address not aligned for short page jump, insert a \'nop\' before the destination address", address);
 660                                                                 }
 661                                                         }
 662                                                 }
 663                                         }
 664
 665                                         if ((reg2 < -16) || (reg2 > 15))
 666                                         {
 667                                                 error("relative jump out of range");
 668                                                 break;
 669                                         }
 670
 671                                         *locp = (char)(*locp | ((reg2 >> 3) & 0x03));
 672                                         locp++;
 673                                         *locp = (char)(*locp | ((reg2 & 0x07) << 5));
 674                                         break;
 675                                 }
 676
 677                                 if ((w & 0x0F00) == FU_NUM15)
 678                                 {
 679                                         if (eval < -16 || eval > 15)
 680                                         {
 681                                                 error("constant out of range");
 682                                                 break;
 683                                         }
 684
 685                                         *locp = (char)(*locp | ((eval >> 3) & 0x03));
 686                                         locp++;
 687                                         *locp = (char)(*locp | ((eval & 0x07) << 5));
 688                                         break;
 689                                 }
 690
 691                                 if ((w & 0x0F00) == FU_NUM31)
 692                                 {
 693                                         if (eval < 0 || eval > 31)
 694                                         {
 695                                                 error("constant out of range");
 696                                                 break;
 697                                         }
 698
 699                                         *locp = (char)(*locp | ((eval >> 3) & 0x03));
 700                                         locp++;
 701                                         *locp = (char)(*locp | ((eval & 0x07) << 5));
 702                                         break;
 703                                 }
 704
 705                                 if ((w & 0x0F00) == FU_NUM32)
 706                                 {
 707                                         if (eval < 1 || eval > 32)
 708                                         {
 709                                                 error("constant out of range");
 710                                                 break;
 711                                         }
 712
 713                                         if (w & FU_SUB32)
 714                                                 eval = (32 - eval);
 715
 716                                         eval = (eval == 32) ? 0 : eval;
 717                                         *locp = (char)(*locp | ((eval >> 3) & 0x03));
 718                                         locp++;
 719                                         *locp = (char)(*locp | ((eval & 0x07) << 5));
 720                                         break;
 721                                 }
 722
 723                                 if ((w & 0x0F00) == FU_REGONE)
 724                                 {
 725                                         if (eval < 0 || eval > 31)
 726                                         {
 727                                                 error("register value out of range");
 728                                                 break;
 729                                         }
 730
 731                                         *locp = (char)(*locp | ((eval >> 3) & 0x03));
 732                                         locp++;
 733                                         *locp = (char)(*locp | ((eval & 0x07) << 5));
 734                                         break;
 735                                 }
 736
 737                                 if ((w & 0x0F00) == FU_REGTWO)
 738                                 {
 739                                         if (eval < 0 || eval > 31)
 740                                         {
 741                                                 error("register value out of range");
 742                                                 break;
 743                                         }
 744
 745                                         locp++;
 746                                         *locp = (char)(*locp | (eval & 0x1F));
 747                                         break;
 748                                 }
 749
 750                                 if (!(eattr & DEFINED))
 751                                 {
 752                                         if (w & FU_PCREL)
 753                                                 w = MPCREL | MWORD;
 754                                         else
 755                                                 w = MWORD;
 756
 757                                         rmark(sno, loc, 0, w, esym);
 758                                 }
 759                                 else
 760                                 {
 761                                         if (tdb)
 762                                                 rmark(sno, loc, tdb, MWORD, NULL);
 763
 764                                         if (w & FU_SEXT)
 765                                         {
 766                                                 if (eval + 0x10000 >= 0x20000)
 767                                                         goto range;
 768                                         }
 769                                         else
 770                                         {
 771                                                 // Range-check BRA and DBRA
 772                                                 if (w & FU_ISBRA)
 773                                                 {
 774                                                         if (eval + 0x8000 >= 0x10000)
 775                                                         goto range;
 776                                                 }
 777                                                 else if (eval >= 0x10000)
 778                                                         goto range;
 779                                         }
 780                                 }
 781
 782                                 *locp++ = (char)(eval >> 8);
 783                                 *locp = (char)eval;
 784                                 break;
 785                         // Fixup LONG forward references;
 786                         // the long could be unaligned in the section buffer, so be careful
 787                         // (again).
 788                         case FU_LONG:
 789                                 if ((w & 0x0F00) == FU_MOVEI)
 790                                 {
 791                                         address = loc + 4;
 792
 793                                         if (eattr & DEFINED)
 794                                         {
 795                                                 for(j=0; j<fwindex; j++)
 796                                                 {
 797                                                         if (fwdjump[j] == address)
 798                                                         {
 799                                                                 page_jump = (address & 0xFFFFFF00) - (eval & 0xFFFFFF00);
 800
 801                                                                 if (page_jump)
 802                                                                 {
 803                                                                         if (eval % 4)
 804                                                                         {
 805                                                                                 err_setup();
 806                                                                                 sprintf(buf, "* \'jump\' at $%08X - destination address not aligned for long page jump, insert a \'nop\' before the destination address", address);
 807
 808                                                                                 if (listing > 0)
 809                                                                                         ship_ln(buf);
 810
 811                                                                                 if (err_flag)
 812                                                                                         write(err_fd, buf, (LONG)strlen(buf));
 813                                                                                 else
 814                                                                                         printf("%s\n", buf);
 815                                                                         }
 816                                                                 }
 817                                                                 else
 818                                                                 {
 819                                                                         if (!(eval & 0x0000000F) || ((eval - 2) % 4))
 820                                                                         {
 821                                                                                 err_setup();
 822                                                                                 sprintf(buf, "* \'jump\' at $%08X - destination address not aligned for short page jump, insert a \'nop\' before the destination address", address);
 823
 824                                                                                 if (listing > 0)
 825                                                                                         ship_ln(buf);
 826
 827                                                                                 if (err_flag)
 828                                                                                         write(err_fd, buf, (LONG)strlen(buf));
 829                                                                                 else
 830                                                                                         printf("%s\n", buf);
 831                                                                         }
 832                                                                 }
 833
 834                                                                 // Clear this jump as it has been checked
 835                                                                 fwdjump[j] = 0;
 836                                                                 j = fwindex;
 837                                                         }
 838                                                 }
 839                                         }
 840
 841                                         eval = ((eval >> 16) & 0x0000FFFF) | ((eval << 16) & 0xFFFF0000);
 842                                         flags = (MLONG|MMOVEI);
 843                                 }
 844                                 else
 845                                         flags = MLONG;
 846
 847                                 if (!(eattr & DEFINED))
 848                                 {
 849                                         rmark(sno, loc, 0, flags, esym);
 850                                 }
 851                                 else if (tdb)
 852                                 {
 853                                         rmark(sno, loc, tdb, flags, NULL);
 854                                 }
 855
 856                                 *locp++ = (char)(eval >> 24);
 857                                 *locp++ = (char)(eval >> 16);
 858                                 *locp++ = (char)(eval >> 8);
 859                                 *locp = (char)eval;
 860                                 break;
 861                         // Fixup a 3-bit "QUICK" reference in bits 9..1
 862                         // (range of 1..8) in a word.  Really bits 1..3 in a byte.
 863                         case FU_QUICK:
 864                                 if (!(eattr & DEFINED))
 865                                 {
 866                                         error("External quick reference");
 867                                         continue;
 868                                 }
 869
 870                                 if (eval < 1 || eval > 8)
 871                                         goto range;
 872
 873                                 *locp |= (eval & 7) << 1;
 874                                 break;
 875                         // Fix up 6502 funny branch
 876                         case FU_6BRA:
 877                                 eval -= (loc + 1);
 878
 879                                 if (eval + 0x80 >= 0x100)
 880                                         goto range;
 881
 882                                 *locp = (char)eval;
 883                                 break;
 884                         default:
 885                                 interror(4);                                 // Bad fixup type
 886                                 // NOTREACHED
 887                         }
 888                         continue;
 889 range:
 890                         error("expression out of range");
 891                 }
 892
 893                 ch = ch->chnext;
 894         }
 895         while (ch != NULL);
 896
 897         return 0;
 898 }