2 // RMAC - Renamed Macro Assembler for all Atari computers
3 // SECT.C - Code Generation, Fixups and Section Management
4 // Copyright (C) 199x Landon Dyer, 2011-2021 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
23 // Function prototypes
24 void MakeSection(int, uint16_t);
25 void SwitchSection(int);
27 // Section descriptors
28 SECT sect[NSECTS]; // All sections...
29 int cursect; // Current section number
31 // These are copied from the section descriptor, the current code chunk
32 // descriptor and the current fixup chunk descriptor when a switch is made into
33 // a section. They are copied back to the descriptors when the section is left.
34 uint16_t scattr; // Section attributes
35 uint32_t sloc; // Current loc in section
37 CHUNK * scode; // Current (last) code chunk
38 uint32_t challoc; // # bytes alloc'd to code chunk
39 uint32_t ch_size; // # bytes used in code chunk
40 uint8_t * chptr; // Deposit point in code chunk buffer
41 uint8_t * chptr_opcode; // Backup of chptr, updated before entering code generators
43 // Return a size (SIZB, SIZW, SIZL) or 0, depending on what kind of fixup is
44 // associated with a location.
45 static uint8_t fusiztab[] = {
56 // Offset to REAL fixup location
57 static uint8_t fusizoffs[] = {
70 // Initialize sections; setup initial ABS, TEXT, DATA and BSS sections
72 void InitSection(void)
74 // Initialize all sections
75 for(int i=0; i<NSECTS; i++)
78 // Construct default sections, make TEXT the current section
79 MakeSection(ABS, SUSED | SABS | SBSS); // ABS
80 MakeSection(TEXT, SUSED | TEXT ); // TEXT
81 MakeSection(DATA, SUSED | DATA ); // DATA
82 MakeSection(BSS, SUSED | BSS | SBSS); // BSS
83 MakeSection(M6502, SUSED | TEXT ); // 6502 code section
84 MakeSection(M56001P, SUSED | SABS ); // DSP 56001 Program RAM
85 MakeSection(M56001X, SUSED | SABS ); // DSP 56001 X RAM
86 MakeSection(M56001Y, SUSED | SABS ); // DSP 56001 Y RAM
88 // Switch to TEXT for starters
94 // Make a new (clean) section
96 void MakeSection(int sno, uint16_t attr)
98 SECT * sp = §[sno];
102 sp->scode = sp->sfcode = NULL;
103 sp->sfix = sp->sffix = NULL;
108 // Switch to another section (copy section & chunk descriptors to global vars
111 void SwitchSection(int sno)
115 SECT * sp = §[sno];
117 m6502 = (sno == M6502); // Set 6502-mode flag
123 orgaddr = sp->orgaddr;
125 // Copy code chunk vars
126 if ((cp = scode) != NULL)
128 challoc = cp->challoc;
129 ch_size = cp->ch_size;
130 chptr = cp->chptr + ch_size;
132 // For 6502 mode, add the last org'd address
135 Because the way this is set up it treats the 6502 assembly space as a single 64K space (+ 16 bytes, for some unknown reason) and just bobbles around inside that space and uses a stack of org "pointers" to show where the data ended up.
137 This is a shitty way to handle things, and we can do better than this! :-P
139 Really, there's no reason to have the 6502 (or DSP56001 for that matter) have their own private sections for this kind of thing, as there's literally *no* chance that it would be mingled with 68K+ code. It should be able to use the TEXT, DATA & BSS sections just like the 68K.
141 Or should it? After looking at the code, maybe it's better to keep the 56001 sections segregated from the rest. But we can still make the 6502 stuff better.
144 chptr = cp->chptr + orgaddr;
147 challoc = ch_size = 0;
152 // Save current section
154 void SaveSection(void)
156 SECT * sp = §[cursect];
158 sp->scattr = scattr; // Bailout section vars
160 sp->orgaddr = orgaddr;
162 if (scode != NULL) // Bailout code chunk (if any)
163 scode->ch_size = ch_size;
168 // Test to see if a location has a fixup set on it. This is used by the
169 // listing generator to print 'xx's instead of '00's for forward references
171 int fixtest(int sno, uint32_t loc)
173 // Force update to sect[] variables
176 // Ugly linear search for a mark on our location. The speed doesn't
177 // matter, since this is only done when generating a listing, which is
179 for(FIXUP * fp=sect[sno].sffix; fp!=NULL; fp=fp->next)
181 uint32_t w = fp->attr;
182 uint32_t xloc = fp->loc + (int)fusizoffs[w & FUMASK];
185 return (int)fusiztab[w & FUMASK];
193 // Check that there are at least 'amt' bytes left in the current chunk. If
194 // there are not, allocate another chunk of at least CH_CODE_SIZE bytes or
195 // 'amt', whichever is larger.
197 // If 'amt' is zero, ensure there are at least CH_THRESHOLD bytes, likewise.
199 void chcheck(uint32_t amt)
201 DEBUG { printf("chcheck(%u)\n", amt); }
203 // If in BSS section, no allocation required
210 DEBUG { printf(" challoc=%i, ch_size=%i, diff=%i\n", challoc, ch_size, challoc - ch_size); }
212 if ((int)(challoc - ch_size) >= (int)amt)
215 if (amt < CH_CODE_SIZE)
218 DEBUG { printf(" amt (adjusted)=%u\n", amt); }
219 SECT * p = §[cursect];
220 CHUNK * cp = malloc(sizeof(CHUNK) + amt);
225 // First chunk in section
232 // Add second and on to previous chunk
235 scode->ch_size = ch_size; // Save old chunk's globals
238 // Setup chunk and global vars
240 So, whenever there's an ORG in a 56K section, it sets sloc TO THE ADDRESS IN THE ORG. Also, the loc/sloc are incremented by 1s, which means to alias correctly to the byte-oriented memory model we have here, we have to fix that kind of crap.
242 cp->chloc = sloc; // <-- HERE'S THE PROBLEM FOR 56K :-/
244 challoc = cp->challoc = amt;
245 ch_size = cp->ch_size = 0;
246 chptr = cp->chptr = ((uint8_t *)cp) + sizeof(CHUNK);
247 scode = p->scode = cp;
251 OK, so this is a bit shite, but at least it gets things working the way they should. The right way to do this is not rely on sloc & friends for the right fixup address but to have an accurate model of the thing. That will probably come with v2.0.1 :-P
253 So the problem is, d_org sets sloc to the address of the ORG statement, and that gives an incorrect base for the fixup. And so when a second (or later) chunk is allocated, it gets set wrong. Further complicating things is that the orgaddress *does not* get used in a typical way with the DSP56001 code, and, as such, causes incorrect addresses to be generated. All that has to be dealt with in order to get this right and do away with this kludge.
255 if (((cursect == M56001P) || (cursect == M56001X) || (cursect == M56001Y)) && !first)
256 cp->chloc = cp->chprev->chloc + cp->chprev->ch_size;
263 // Arrange for a fixup on a location
265 int AddFixup(uint32_t attr, uint32_t loc, TOKEN * fexpr)
267 uint16_t exprlen = 0;
269 uint32_t _orgaddr = 0;
271 // First, check to see if the expression is a bare label, otherwise, force
272 // the FU_EXPR flag into the attributes and count the tokens.
273 if ((fexpr[0] == SYMBOL) && (fexpr[2] == ENDEXPR))
275 symbol = symbolPtr[fexpr[1]];
277 // Save the org address for JR RISC instruction
278 if ((attr & FUMASKRISC) == FU_JR)
284 exprlen = ExpressionLength(fexpr);
287 // Second, check to see if it's a DSP56001 fixup, and force the FU_56001
288 // flag into the attributes if so; also save the current org address.
289 if (attr & FUMASKDSP)
292 // Save the exact spot in this chunk where the fixup should go
293 _orgaddr = chptr - scode->chptr + scode->chloc;
296 // Allocate space for the fixup + any expression
297 FIXUP * fixup = malloc(sizeof(FIXUP) + (sizeof(TOKEN) * exprlen));
299 // Store the relevant fixup information in the FIXUP
303 fixup->fileno = cfileno;
304 fixup->lineno = curlineno;
306 fixup->symbol = symbol;
307 fixup->orgaddr = _orgaddr;
309 // Copy the passed in expression to the FIXUP, if any
312 fixup->expr = (TOKEN *)((uint8_t *)fixup + sizeof(FIXUP));
313 memcpy(fixup->expr, fexpr, sizeof(TOKEN) * exprlen);
316 // Finally, put the FIXUP in the current section's linked list
317 if (sect[cursect].sffix == NULL)
319 sect[cursect].sffix = fixup;
320 sect[cursect].sfix = fixup;
324 sect[cursect].sfix->next = fixup;
325 sect[cursect].sfix = fixup;
328 DEBUG { printf("AddFixup: sno=%u, l#=%u, attr=$%X, loc=$%X, expr=%p, sym=%p, org=$%X\n", cursect, fixup->lineno, fixup->attr, fixup->loc, (void *)fixup->expr, (void *)fixup->symbol, fixup->orgaddr);
330 printf(" name: %s, value: $%lX\n", symbol->sname, symbol->svalue);
338 // Resolve fixups in the passed in section
340 int ResolveFixups(int sno)
342 SECT * sc = §[sno];
344 // "Cache" first chunk
345 CHUNK * cch = sc->sfcode;
347 // Can't fixup a section with nothing in it
351 // Wire the 6502 segment's size to its allocated size (64K)
353 cch->ch_size = cch->challoc;
355 // Get first fixup for the passed in section
356 FIXUP * fixup = sect[sno].sffix;
358 while (fixup != NULL)
360 // We do it this way because we have continues everywhere... :-P
364 uint32_t dw = fup->attr; // Fixup long (type + modes + flags)
365 uint32_t loc = fup->loc; // Location to fixup
366 cfileno = fup->fileno;
367 curlineno = fup->lineno;
368 DEBUG { printf("ResolveFixups: sect#=%u, l#=%u, attr=$%X, loc=$%X, expr=%p, sym=%p, org=$%X\n", sno, fup->lineno, fup->attr, fup->loc, (void *)fup->expr, (void *)fup->symbol, fup->orgaddr); }
370 // This is based on global vars cfileno, curfname :-P
371 // This approach is kinda meh as well. I think we can do better
373 SetFilenameForErrorReporting();
375 if ((sno == M56001P) || (sno == M56001X) || (sno == M56001Y) || (sno == M56001L))
378 // Search for chunk containing location to fix up; compute a
379 // pointer to the location (in the chunk). Often we will find the
380 // Fixup is in the "cached" chunk, so the linear-search is seldom
382 if (loc < cch->chloc || loc >= (cch->chloc + cch->ch_size))
384 for(cch=sc->sfcode; cch!=NULL; cch=cch->chnext)
386 if (loc >= cch->chloc && loc < (cch->chloc + cch->ch_size))
392 // Fixup (loc) is out of range--this should never happen!
393 // Once we call this function, it winds down immediately; it
399 // Location to fix (in current chunk)
400 // We use the address of the chunk that loc is actually in, then
401 // subtract the chunk's starting location from loc to get the offset
402 // into the current chunk.
403 uint8_t * locp = cch->chptr + (loc - cch->chloc);
405 uint16_t eattr = 0; // Expression attrib
406 SYM * esym = NULL; // External symbol involved in expr
407 uint64_t eval; // Expression value
408 uint16_t flags; // Mark flags
410 // Compute expression/symbol value and attributes
412 // Complex expression
415 // evexpr presumably issues the errors/warnings here
416 if (evexpr(fup->expr, &eval, &eattr, &esym) != OK)
419 if ((CHECK_OPTS(OPT_PC_RELATIVE)) && (eattr & REFERENCED) && (eattr & DEFINED) && (!(eattr & EQUATED)))
421 error("relocation not allowed");
428 SYM * sy = fup->symbol;
431 if ((CHECK_OPTS(OPT_PC_RELATIVE)) && (eattr & REFERENCED) && (eattr & DEFINED) && (!(eattr & EQUATED)))
433 error("relocation not allowed");
442 // If the symbol is not defined, but global, set esym to sy
443 if ((eattr & (GLOBAL | DEFINED)) == GLOBAL)
446 DEBUG { printf(" name: %s, value: $%" PRIX64 "\n", sy->sname, sy->svalue); }
449 uint16_t tdb = eattr & TDB;
451 // If the expression/symbol is undefined and no external symbol is
452 // involved, then that's an error.
453 if (!(eattr & DEFINED) && (esym == NULL))
461 // If a PC-relative fixup is undefined, its value is *not* subtracted
462 // from the location (that will happen in the linker when the external
463 // reference is resolved).
465 // PC-relative fixups must be DEFINED and either in the same section
466 // (whereupon the subtraction takes place) or ABS (with no subtract).
467 if ((dw & FU_PCREL) || (dw & FU_PCRELX))
475 // In this instruction the PC is located a DWORD away
481 // Allow cross-section PCREL fixups in Alcyon mode
482 if (prg_flag || (obj_format == RAW))
487 // Shouldn't there be a break here, since otherwise, it will point to the DATA section?
490 eval += sect[TEXT].sloc;
493 eval += sect[TEXT].sloc + sect[DATA].sloc;
496 error("invalid section");
502 // In this instruction the PC is located a DWORD away
508 error("PC-relative expr across sections");
513 if (optim_warn_flag && (dw & FU_LBRA) && (eval + 0x80 < 0x100))
514 warn("unoptimized short branch");
517 // Be sure to clear any TDB flags, since we handled it just now
522 // Handle fixup classes
525 // FU_BBRA fixes up a one-byte branch offset.
527 if (!(eattr & DEFINED))
529 error("external short branch");
535 if (eval + 0x80 >= 0x100)
540 if (*locp) // optim_flags[OPT_NULL_BRA] is stored there, check the comment in mach.s under m_br
547 warn("bra.s with zero offset converted to NOP");
553 error("illegal bra.s with zero offset");
558 *++locp = (uint8_t)eval;
561 // Fixup one-byte value at locp + 1.
566 // Fixup one-byte forward references
568 if (!(eattr & DEFINED))
570 error("external byte reference");
576 error("non-absolute byte reference");
580 if ((dw & FU_PCREL) && ((eval + 0x80) >= 0x100))
585 if ((eval + 0x100) >= 0x200)
588 else if (eval >= 0x100)
591 *locp = (uint8_t)eval;
594 // Fixup high/low byte off word for 6502
596 if (!(eattr & DEFINED))
598 error("external byte reference");
602 *locp = (uint8_t)(eval >> 8);
606 if (!(eattr & DEFINED))
608 error("external byte reference");
612 *locp = (uint8_t)eval;
615 // Fixup WORD forward references; the word could be unaligned in the
616 // section buffer, so we have to be careful. (? careful about what?)
618 if ((dw & FUMASKRISC) == FU_JR)
620 int reg = (signed)((eval - ((fup->orgaddr ? fup->orgaddr : loc) + 2)) / 2);
622 if ((reg < -16) || (reg > 15))
624 error("relative jump out of range");
628 *locp |= ((uint8_t)reg >> 3) & 0x03;
630 *locp |= ((uint8_t)reg & 0x07) << 5;
633 else if ((dw & FUMASKRISC) == FU_NUM15)
635 if (((int)eval < -16) || ((int)eval > 15))
637 error("constant out of range (-16 - +15)");
641 *locp |= ((uint8_t)eval >> 3) & 0x03;
643 *locp |= ((uint8_t)eval & 0x07) << 5;
646 else if ((dw & FUMASKRISC) == FU_NUM31)
650 error("constant out of range (0-31)");
654 *locp |= ((uint8_t)eval >> 3) & 0x03;
656 *locp |= ((uint8_t)eval & 0x07) << 5;
659 else if ((dw & FUMASKRISC) == FU_NUM32)
661 if ((eval < 1) || (eval > 32))
663 error("constant out of range (1-32)");
670 eval = (eval == 32) ? 0 : eval;
671 *locp |= ((uint8_t)eval >> 3) & 0x03;
673 *locp |= ((uint8_t)eval & 0x07) << 5;
676 else if ((dw & FUMASKRISC) == FU_REGONE)
680 error("register one value out of range");
684 *locp |= ((uint8_t)eval >> 3) & 0x03;
686 *locp |= ((uint8_t)eval & 0x07) << 5;
689 else if ((dw & FUMASKRISC) == FU_REGTWO)
693 error("register two value out of range");
698 *locp |= (uint8_t)eval & 0x1F;
702 if (!(eattr & DEFINED))
709 MarkRelocatable(sno, loc, 0, flags, esym);
714 MarkRelocatable(sno, loc, tdb, MWORD, NULL);
718 if (eval + 0x10000 >= 0x20000)
723 // Range-check BRA and DBRA
726 if (eval + 0x8000 >= 0x10000)
729 else if (eval >= 0x10000)
734 // 6502 words are little endian, so handle that here
736 SETLE16(locp, 0, eval)
738 SETBE16(locp, 0, eval)
742 // Fixup LONG forward references; the long could be unaligned in the
743 // section buffer, so be careful (again).
747 if ((dw & FUMASKRISC) == FU_MOVEI)
749 // Long constant in MOVEI # is word-swapped, so fix it here
750 eval = WORDSWAP32(eval);
754 // If the symbol is undefined, make sure to pass the symbol in
755 // to the MarkRelocatable() function.
756 if (!(eattr & DEFINED))
757 MarkRelocatable(sno, loc, 0, flags, esym);
759 MarkRelocatable(sno, loc, tdb, flags, NULL);
761 SETBE32(locp, 0, eval);
764 // Fixup QUAD forward references (mainly used by the OP assembler)
768 uint64_t quad = GETBE64(locp, 0);
769 uint64_t addr = eval;
771 //Hmm, not sure how this can be set, since it's only set if it's a DSP56001 fixup or a FU_JR... :-/
773 // addr = fup->orgaddr;
775 eval = (quad & 0xFFFFFC0000FFFFFFLL) | ((addr & 0x3FFFF8) << 21);
777 else if (dw & FU_OBJDATA)
779 // If it's in a TEXT or DATA section, be sure to mark for a
782 MarkRelocatable(sno, loc, tdb, MQUAD, NULL);
784 uint64_t quad = GETBE64(locp, 0);
785 uint64_t addr = eval;
787 //Hmm, not sure how this can be set, since it's only set if it's a DSP56001 fixup or a FU_JR... :-/
789 // addr = fup->orgaddr;
791 eval = (quad & 0x000007FFFFFFFFFFLL) | ((addr & 0xFFFFF8) << 40);
794 SETBE64(locp, 0, eval);
797 // Fixup a 3-bit "QUICK" reference in bits 9..1
798 // (range of 1..8) in a word. [Really bits 1..3 in a byte.]
800 if (!(eattr & DEFINED))
802 error("External quick reference");
806 if ((eval < 1) || (eval > 8))
809 *locp |= (eval & 7) << 1;
812 // Fix up 6502 funny branch
816 if (eval + 0x80 >= 0x100)
819 *locp = (uint8_t)eval;
822 // Fixup DSP56001 addresses
824 switch (dw & FUMASKDSP)
826 // DSPIMM5 actually is clamped from 0 to 23 for our purposes
827 // and does not use the full 5 bit range.
831 error("immediate value must be between 0 and 23");
838 // This is a 12-bit address encoded into the lower 12
839 // bits of a DSP word
843 error("address out of range ($0-$FFF)");
847 locp[1] |= eval >> 8;
848 locp[2] = eval & 0xFF;
851 // This is a full DSP word containing Effective Address Extension
854 if (eval >= 0x1000000)
856 error("value out of range ($0-$FFFFFF)");
860 locp[0] = (uint8_t)((eval >> 16) & 0xFF);
861 locp[1] = (uint8_t)((eval >> 8) & 0xFF);
862 locp[2] = (uint8_t)(eval & 0xFF);
865 // This is a 16bit absolute address into a 24bit field
869 error("address out of range ($0-$FFFF)");
873 locp[1] = (uint8_t)(eval >> 8);
874 locp[2] = (uint8_t)eval;
877 // This is 12-bit immediate short data
878 // The upper nibble goes into the last byte's low nibble
879 // while the remainder 8 bits go into the 2nd byte.
883 error("immediate out of range ($0-$FFF)");
887 locp[1] = (uint8_t)eval;
888 locp[2] |= (uint8_t)(eval >> 8);
891 // This is 8-bit immediate short data
892 // which goes into the middle byte of a DSP word.
896 error("immediate out of range ($0-$FF)");
900 locp[1] = (uint8_t)eval;
903 // This is a 6 bit absoulte short address. It occupies the low 6
904 // bits of the middle byte of a DSP word.
908 error("address must be between 0 and 63");
915 // This is a 6 bit absoulte short address. It occupies the low 6
916 // bits of the middle byte of a DSP word.
918 if (eval < 0xFFFFFFC0)
920 error("address must be between $FFC0 and $FFFF");
924 locp[1] |= eval & 0x3F;
927 // Shamus: I'm pretty sure these don't make any sense...
929 warn("FU_DSPIMMFL8 missing implementation\n%s", "And you may ask yourself, \"Self, how did I get here?\"");
933 warn("FU_DSPIMMFL16 missing implementation\n%s", "And you may ask yourself, \"Self, how did I get here?\"");
937 warn("FU_DSPIMMFL24 missing implementation\n%s", "And you may ask yourself, \"Self, how did I get here?\"");
940 // Bad fixup type--this should *never* happen!
947 // Fixup a 4-byte float
949 warn("FU_FLOATSING missing implementation\n%s", "And you may ask yourself, \"Self, how did I get here?\"");
952 // Fixup a 8-byte float
954 warn("FU_FLOATDOUB missing implementation\n%s", "And you may ask yourself, \"Self, how did I get here?\"");
957 // Fixup a 12-byte float
959 warn("FU_FLOATEXT missing implementation\n%s", "And you may ask yourself, \"Self, how did I get here?\"");
963 // Bad fixup type--this should *never* happen!
964 // Once we call this function, it winds down immediately; it
971 error("expression out of range");
979 // Resolve all fixups
981 int ResolveAllFixups(void)
983 // Make undefined symbols GLOBL
985 ForceUndefinedSymbolsGlobal();
987 DEBUG printf("Resolving TEXT sections...\n");
989 DEBUG printf("Resolving DATA sections...\n");
991 DEBUG printf("Resolving 6502 sections...\n");
992 ResolveFixups(M6502); // Fixup 6502 section (if any)
993 DEBUG printf("Resolving DSP56001 P: sections...\n");
994 ResolveFixups(M56001P); // Fixup 56001 P: section (if any)
995 DEBUG printf("Resolving DSP56001 X: sections...\n");
996 ResolveFixups(M56001X); // Fixup 56001 X: section (if any)
997 DEBUG printf("Resolving DSP56001 Y: sections...\n");
998 ResolveFixups(M56001Y); // Fixup 56001 Y: section (if any)