2 // RMAC - Reboot's Macro Assembler for the Atari Jaguar Console System
3 // EXPR.C - Expression Analyzer
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
20 #define DEF_KW // Declare keyword values
21 #include "kwtab.h" // Incl generated keyword tables & defs
23 // N.B.: The size of tokenClass should be identical to the largest value of
24 // a token; we're assuming 256 but not 100% sure!
25 static char tokenClass[256]; // Generated table of token classes
26 static VALUE evstk[EVSTACKSIZE]; // Evaluator value stack
27 static WORD evattr[EVSTACKSIZE]; // Evaluator attribute stack
29 // Token-class initialization list
32 CONST, SYMBOL, 0, // ID
33 '(', '[', '{', 0, // OPAR
34 ')', ']', '}', 0, // CPAR
35 CR_DEFINED, CR_REFERENCED, // SUNARY (special unary)
38 '!', '~', UNMINUS, 0, // UNARY
39 '*', '/', '%', 0, // MULT
42 LE, GE, '<', '>', NE, '=', 0, // REL
49 const char missym_error[] = "missing symbol";
50 const char str_error[] = "missing symbol or string";
52 // Convert expression to postfix
53 static TOKEN * evalTokenBuffer; // Deposit tokens here (this is really a
54 // pointer to exprbuf from direct.c)
55 // (Can also be from others, like
57 static symbolNum; // Pointer to the entry in symbolPtr[]
61 // Obtain a string value
63 static VALUE str_value(char * p)
68 v = (v << 8) | (*p & 0xFF);
75 // Initialize expression analyzer
77 void InitExpression(void)
82 // Initialize token-class table (all set to END)
86 for(i=0, p=itokcl; *p!=1; p++)
91 tokenClass[(int)(*p)] = (char)i;
99 // Binary operators (all the same precedence)
108 while (tokenClass[*tok] >= MULT)
115 *evalTokenBuffer++ = t;
123 // Unary operators (detect unary '-')
134 class = tokenClass[*tok];
136 if (*tok == '-' || class == UNARY)
146 *evalTokenBuffer++ = t;
148 else if (class == SUNARY)
153 *evalTokenBuffer++ = CONST;
154 *evalTokenBuffer++ = dos_time();
157 *evalTokenBuffer++ = CONST;
158 *evalTokenBuffer++ = dos_date();
160 case CR_MACDEF: // ^^macdef <macro-name>
161 if (*tok++ != SYMBOL)
162 return error(missym_error);
165 w = (lookup(p, MACRO, 0) == NULL ? 0 : 1);
166 *evalTokenBuffer++ = CONST;
167 *evalTokenBuffer++ = (TOKEN)w;
175 if (*tok++ != SYMBOL)
176 return error(missym_error);
179 j = (*p == '.' ? curenv : 0);
180 w = ((sy = lookup(p, LABEL, j)) != NULL && (sy->sattr & w) ? 1 : 0);
181 *evalTokenBuffer++ = CONST;
182 *evalTokenBuffer++ = (TOKEN)w;
185 if (*tok != SYMBOL && *tok != STRING)
186 return error(str_error);
192 return error(comma_error);
194 if (*tok != SYMBOL && *tok != STRING)
195 return error(str_error);
200 w = (WORD)(!strcmp(p, p2));
201 *evalTokenBuffer++ = CONST;
202 *evalTokenBuffer++ = (TOKEN)w;
214 // Terminals (CONSTs) and parenthesis grouping
225 *evalTokenBuffer++ = CONST;
226 *evalTokenBuffer++ = *tok++;
230 j = (*p == '.' ? curenv : 0);
231 sy = lookup(p, LABEL, j);
234 sy = NewSymbol(p, LABEL, j);
236 // Check register bank usage
237 if (sy->sattre & EQUATEDREG)
239 if ((regbank == BANK_0) && (sy->sattre & BANK_1) && !altbankok)
240 warns("equated symbol \'%s\' cannot be used in register bank 0", sy->sname);
242 if ((regbank == BANK_1) && (sy->sattre & BANK_0) && !altbankok)
243 warns("equated symbol \'%s\' cannot be used in register bank 1", sy->sname);
246 *evalTokenBuffer++ = SYMBOL;
247 *evalTokenBuffer++ = symbolNum;
248 symbolPtr[symbolNum] = sy;
252 *evalTokenBuffer++ = CONST;
253 *evalTokenBuffer++ = str_value(string[*tok++]);
260 return error("missing close parenthesis ')'");
268 return error("missing close parenthesis ']'");
272 *evalTokenBuffer++ = ACONST; // Attributed const
273 *evalTokenBuffer++ = sloc; // Current location
274 *evalTokenBuffer++ = cursect | DEFINED; // Store attribs
277 *evalTokenBuffer++ = ACONST; // Attributed const
279 // pcloc == location at start of line
280 *evalTokenBuffer++ = (orgactive ? orgaddr : pcloc);
281 *evalTokenBuffer++ = ABS | DEFINED; // Store attribs
284 return error("bad expression");
292 // Recursive-descent expression analyzer (with some simple speed hacks)
294 int expr(TOKEN * otk, VALUE * a_value, WORD * a_attr, SYM ** a_esym)
296 // Passed in values (once derefenced, that is) can all be zero. They are
297 // there so that the expression analyzer can fill them in as needed. The
298 // expression analyzer gets its input from the global token pointer "tok",
299 // and not from anything passed in by the user.
304 evalTokenBuffer = otk; // Set token pointer to 'exprbuf' (direct.c)
305 // Also set in various other places too (riscasm.c, e.g.)
307 //printf("expr(): tokens 0-2: %i %i %i (%c %c %c); tc[2] = %i\n", tok[0], tok[1], tok[2], tok[0], tok[1], tok[2], tokenClass[tok[2]]);
308 // Optimize for single constant or single symbol.
309 // Shamus: Subtle bug here. EOL token is 101; if you have a constant token
310 // followed by the value 101, it will trigger a bad evaluation here.
311 // This is probably a really bad assumption to be making here...!
312 // (assuming tok[1] == EOL is a single token that is)
313 // if ((tok[1] == EOL)
314 if ((tok[1] == EOL && tok[0] != CONST)
315 || (((*tok == CONST || *tok == SYMBOL) || (*tok >= KW_R0 && *tok <= KW_R31))
316 && (tokenClass[tok[2]] < UNARY)))
318 if (*tok >= KW_R0 && *tok <= KW_R31)
320 *evalTokenBuffer++ = CONST;
321 *evalTokenBuffer++ = *a_value = (*tok - KW_R0);
322 *a_attr = ABS | DEFINED;
329 else if (*tok == CONST)
331 *evalTokenBuffer++ = CONST;
332 *evalTokenBuffer++ = *a_value = tok[1];
333 *a_attr = ABS | DEFINED;
339 //printf("Quick eval in expr(): CONST = %i, tokenClass[tok[2]] = %i\n", *a_value, tokenClass[*tok]);
341 else if (*tok == '*')
343 *evalTokenBuffer++ = CONST;
346 *evalTokenBuffer++ = *a_value = orgaddr;
348 *evalTokenBuffer++ = *a_value = pcloc;
350 *a_attr = ABS | DEFINED;
357 else if (*tok == STRING || *tok == SYMBOL)
360 j = (*p == '.' ? curenv : 0);
361 symbol = lookup(p, LABEL, j);
363 printf("eval: Looking up symbol [=%08X]\n", symbol);
365 printf(" attr=%04X, attre=%08X, val=%i, name=%s\n", symbol->sattr, symbol->sattre, symbol->svalue, symbol->sname);
369 symbol = NewSymbol(p, LABEL, j);
371 symbol->sattr |= REFERENCED;
373 // Check for undefined register equates
374 if (symbol->sattre & UNDEF_EQUR)
376 errors("undefined register equate '%s'", symbol->sname);
377 //if we return right away, it returns some spurious errors...
381 // Check register bank usage
382 if (symbol->sattre & EQUATEDREG)
384 if ((regbank == BANK_0) && (symbol->sattre & BANK_1) && !altbankok)
385 warns("equated symbol '%s' cannot be used in register bank 0", symbol->sname);
387 if ((regbank == BANK_1) && (symbol->sattre & BANK_0) && !altbankok)
388 warns("equated symbol '%s' cannot be used in register bank 1", symbol->sname);
391 *evalTokenBuffer++ = SYMBOL;
393 *evalTokenBuffer++ = (TOKEN)symbol;
396 While this approach works, it's wasteful. It would be better to use something
397 that's already available, like the symbol "order defined" table (which needs to
398 be converted from a linked list into an array).
400 *evalTokenBuffer++ = symbolNum;
401 symbolPtr[symbolNum] = symbol;
405 if (symbol->sattr & DEFINED)
406 *a_value = symbol->svalue;
411 All that extra crap that was put into the svalue when doing the equr stuff is
412 thrown away right here. What the hell is it for?
414 if (symbol->sattre & EQUATEDREG)
417 *a_attr = (WORD)(symbol->sattr & ~GLOBAL);
419 if ((symbol->sattr & (GLOBAL | DEFINED)) == GLOBAL && a_esym != NULL)
426 // Unknown type here... Alert the user!
427 error("undefined RISC register in expression");
428 // Prevent spurious error reporting...
433 *evalTokenBuffer++ = ENDEXPR;
440 *evalTokenBuffer++ = ENDEXPR;
441 return evexpr(otk, a_value, a_attr, a_esym);
446 // Evaluate expression.
447 // If the expression involves only ONE external symbol, the expression is
448 // UNDEFINED, but it's value includes everything but the symbol value, and
449 // `a_esym' is set to the external symbol.
451 int evexpr(TOKEN * tk, VALUE * a_value, WORD * a_attr, SYM ** a_esym)
460 sval = evstk; // (Empty) initial stack
462 esym = NULL; // No external symbol involved
465 while (*tk != ENDEXPR)
470 //printf("evexpr(): SYMBOL\n");
471 sy = symbolPtr[*tk++];
472 sy->sattr |= REFERENCED; // Set "referenced" bit
474 if (!(sy->sattr & DEFINED))
476 // Reference to undefined symbol
477 if (!(sy->sattr & GLOBAL))
484 if (esym != NULL) // Check for multiple externals
485 return error(seg_error);
490 if (sy->sattr & DEFINED)
492 *++sval = sy->svalue; // Push symbol's value
496 *++sval = 0; // 0 for undefined symbols
499 *++sattr = (WORD)(sy->sattr & ~GLOBAL); // Push attribs
500 sym_seg = (WORD)(sy->sattr & (TEXT | DATA | BSS));
503 //printf("evexpr(): CONST = %i\n", *tk);
504 *++sval = *tk++; // Push value
505 *++sattr = ABS | DEFINED; // Push simple attribs
508 //printf("evexpr(): ACONST = %i\n", *tk);
509 *++sval = *tk++; // Push value
510 *++sattr = (WORD)*tk++; // Push attribs
513 // Binary "+" and "-" matrix:
516 // ----------------------------
517 // ABS | ABS | Sect | Other |
518 // Sect | Sect | [1] | Error |
519 // Other | Other | Error | [1] |
520 // ----------------------------
525 //printf("evexpr(): +\n");
527 --sattr; // Pop attrib
528 *sval += sval[1]; // Compute value
530 if (!(*sattr & (TEXT | DATA | BSS)))
532 else if (sattr[1] & (TEXT | DATA | BSS))
533 return error(seg_error);
537 //printf("evexpr(): -\n");
539 --sattr; // Pop attrib
540 *sval -= sval[1]; // Compute value
542 attr = (WORD)(*sattr & (TEXT | DATA | BSS));
546 else if (sattr[1] & (TEXT | DATA | BSS))
548 if (!(attr & sattr[1]))
549 return error(seg_error);
551 *sattr &= ~(TEXT | DATA | BSS);
555 // Unary operators only work on ABS items
557 //printf("evexpr(): UNMINUS\n");
558 if (*sattr & (TEXT | DATA | BSS))
562 *sattr = ABS | DEFINED; // Expr becomes absolute
565 //printf("evexpr(): !\n");
566 if (*sattr & (TEXT | DATA | BSS))
570 *sattr = ABS | DEFINED; // Expr becomes absolute
573 //printf("evexpr(): ~\n");
574 if (*sattr & (TEXT | DATA | BSS))
578 *sattr = ABS | DEFINED; // Expr becomes absolute
580 // Comparison operators must have two values that
581 // are in the same segment, but that's the only requirement.
583 //printf("evexpr(): LE\n");
587 if ((*sattr & TDB) != (sattr[1] & TDB))
590 *sattr = ABS | DEFINED;
591 *sval = *sval <= sval[1];
594 //printf("evexpr(): GE\n");
598 if ((*sattr & TDB) != (sattr[1] & TDB))
601 *sattr = ABS | DEFINED;
602 *sval = *sval >= sval[1];
605 //printf("evexpr(): >\n");
609 if ((*sattr & TDB) != (sattr[1] & TDB))
612 *sattr = ABS | DEFINED;
613 *sval = *sval > sval[1];
616 //printf("evexpr(): <\n");
620 if ((*sattr & TDB) != (sattr[1] & TDB))
623 *sattr = ABS | DEFINED;
624 *sval = *sval < sval[1];
627 //printf("evexpr(): NE\n");
631 if ((*sattr & TDB) != (sattr[1] & TDB))
634 *sattr = ABS | DEFINED;
635 *sval = *sval != sval[1];
638 //printf("evexpr(): =\n");
642 if ((*sattr & TDB) != (sattr[1] & TDB))
645 *sattr = ABS | DEFINED;
646 *sval = *sval == sval[1];
648 // All other binary operators must have two ABS items
649 // to work with. They all produce an ABS value.
651 //printf("evexpr(): default\n");
652 // GH - Removed for v1.0.15 as part of the fix for indexed loads.
653 //if ((*sattr & (TEXT|DATA|BSS)) || (*--sattr & (TEXT|DATA|BSS)))
655 *sattr = ABS | DEFINED; // Expr becomes absolute
661 --sattr; // Pop attrib
666 --sattr; // Pop attrib
669 return error("divide by zero");
675 --sattr; // Pop attrib
678 return error("mod (%) by zero");
684 --sattr; // Pop attrib
689 --sattr; // Pop attrib
694 --sattr; // Pop attrib
699 --sattr; // Pop attrib
704 --sattr; // Pop attrib
708 interror(5); // Bad operator in expression stream
719 // sym_seg added in 1.0.16 to solve a problem with forward symbols in
720 // expressions where absolute values also existed. The absolutes were
721 // overiding the symbol segments and not being included :(
722 //*a_attr = *sattr | sym_seg; // Copy value + attrib
724 *a_attr = *sattr; // Copy value + attrib