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e88ff79159e28e93c010a73ebde045ee8a6c9132
[dsw-obn.git] / src / oberon.c
1 #include <stdio.h>
2 #include <stdlib.h>
3 #include <stdarg.h>
4 #include <ctype.h>
5 #include <string.h>
6 #include <assert.h>
7 #include <stdbool.h>
8 #include <math.h>
9
10 #include "../include/oberon.h"
11
12 #include "oberon-internals.h"
13 #include "generator.h"
14
15 enum {
16 EOF_ = 0,
17 IDENT,
18 MODULE,
19 SEMICOLON,
20 END,
21 DOT,
22 VAR,
23 COLON,
24 BEGIN,
25 ASSIGN,
26 INTEGER,
27 TRUE,
28 FALSE,
29 LPAREN,
30 RPAREN,
31 EQUAL,
32 NEQ,
33 LESS,
34 LEQ,
35 GREAT,
36 GEQ,
37 IN,
38 IS,
39 PLUS,
40 MINUS,
41 OR,
42 STAR,
43 SLASH,
44 DIV,
45 MOD,
46 AND,
47 NOT,
48 PROCEDURE,
49 COMMA,
50 RETURN,
51 CONST,
52 TYPE,
53 ARRAY,
54 OF,
55 LBRACE,
56 RBRACE,
57 RECORD,
58 POINTER,
59 TO,
60 UPARROW,
61 NIL,
62 IMPORT,
63 REAL,
64 CHAR,
65 STRING,
66 IF,
67 THEN,
68 ELSE,
69 ELSIF,
70 WHILE,
71 DO,
72 REPEAT,
73 UNTIL,
74 FOR,
75 BY,
76 LOOP,
77 EXIT
78 };
79
80 // =======================================================================
81 // UTILS
82 // =======================================================================
83
84 static void
85 oberon_error(oberon_context_t * ctx, const char * fmt, ...)
86 {
87 va_list ptr;
88 va_start(ptr, fmt);
89 fprintf(stderr, "error: ");
90 vfprintf(stderr, fmt, ptr);
91 fprintf(stderr, "\n");
92 fprintf(stderr, " code_index = %i\n", ctx -> code_index);
93 fprintf(stderr, " c = %c\n", ctx -> c);
94 fprintf(stderr, " token = %i\n", ctx -> token);
95 va_end(ptr);
96 exit(1);
97 }
98
99 static oberon_type_t *
100 oberon_new_type_ptr(int class)
101 {
102 oberon_type_t * x = malloc(sizeof *x);
103 memset(x, 0, sizeof *x);
104 x -> class = class;
105 return x;
106 }
107
108 static oberon_type_t *
109 oberon_new_type_integer(int size)
110 {
111 oberon_type_t * x;
112 x = oberon_new_type_ptr(OBERON_TYPE_INTEGER);
113 x -> size = size;
114 return x;
115 }
116
117 static oberon_type_t *
118 oberon_new_type_boolean()
119 {
120 oberon_type_t * x;
121 x = oberon_new_type_ptr(OBERON_TYPE_BOOLEAN);
122 return x;
123 }
124
125 static oberon_type_t *
126 oberon_new_type_real(int size)
127 {
128 oberon_type_t * x;
129 x = oberon_new_type_ptr(OBERON_TYPE_REAL);
130 x -> size = size;
131 return x;
132 }
133
134 static oberon_type_t *
135 oberon_new_type_char(int size)
136 {
137 oberon_type_t * x;
138 x = oberon_new_type_ptr(OBERON_TYPE_CHAR);
139 x -> size = size;
140 return x;
141 }
142
143 static oberon_type_t *
144 oberon_new_type_string(int size)
145 {
146 oberon_type_t * x;
147 x = oberon_new_type_ptr(OBERON_TYPE_STRING);
148 x -> size = size;
149 return x;
150 }
151
152 // =======================================================================
153 // TABLE
154 // =======================================================================
155
156 static oberon_scope_t *
157 oberon_open_scope(oberon_context_t * ctx)
158 {
159 oberon_scope_t * scope = calloc(1, sizeof *scope);
160 oberon_object_t * list = calloc(1, sizeof *list);
161
162 scope -> ctx = ctx;
163 scope -> list = list;
164 scope -> up = ctx -> decl;
165
166 if(scope -> up)
167 {
168 scope -> local = scope -> up -> local;
169 scope -> parent = scope -> up -> parent;
170 scope -> parent_type = scope -> up -> parent_type;
171 scope -> exit_label = scope -> up -> exit_label;
172 }
173
174 ctx -> decl = scope;
175 return scope;
176 }
177
178 static void
179 oberon_close_scope(oberon_scope_t * scope)
180 {
181 oberon_context_t * ctx = scope -> ctx;
182 ctx -> decl = scope -> up;
183 }
184
185 static oberon_object_t *
186 oberon_find_object_in_list(oberon_object_t * list, char * name)
187 {
188 oberon_object_t * x = list;
189 while(x -> next && strcmp(x -> next -> name, name) != 0)
190 {
191 x = x -> next;
192 }
193 return x -> next;
194 }
195
196 static oberon_object_t *
197 oberon_find_object(oberon_scope_t * scope, char * name, bool check_it)
198 {
199 oberon_object_t * result = NULL;
200
201 oberon_scope_t * s = scope;
202 while(result == NULL && s != NULL)
203 {
204 result = oberon_find_object_in_list(s -> list, name);
205 s = s -> up;
206 }
207
208 if(check_it && result == NULL)
209 {
210 oberon_error(scope -> ctx, "undefined ident %s", name);
211 }
212
213 return result;
214 }
215
216 static oberon_object_t *
217 oberon_create_object(oberon_scope_t * scope, char * name, int class, bool export, bool read_only)
218 {
219 oberon_object_t * newvar = malloc(sizeof *newvar);
220 memset(newvar, 0, sizeof *newvar);
221 newvar -> name = name;
222 newvar -> class = class;
223 newvar -> export = export;
224 newvar -> read_only = read_only;
225 newvar -> local = scope -> local;
226 newvar -> parent = scope -> parent;
227 newvar -> parent_type = scope -> parent_type;
228 newvar -> module = scope -> ctx -> mod;
229 return newvar;
230 }
231
232 static oberon_object_t *
233 oberon_define_object(oberon_scope_t * scope, char * name, int class, bool export, bool read_only, bool check_upscope)
234 {
235 if(check_upscope)
236 {
237 if(oberon_find_object(scope -> up, name, false))
238 {
239 oberon_error(scope -> ctx, "already defined");
240 }
241 }
242
243 oberon_object_t * x = scope -> list;
244 while(x -> next && strcmp(x -> next -> name, name) != 0)
245 {
246 x = x -> next;
247 }
248
249 if(x -> next)
250 {
251 oberon_error(scope -> ctx, "already defined");
252 }
253
254 oberon_object_t * newvar;
255 newvar = oberon_create_object(scope, name, class, export, read_only);
256 x -> next = newvar;
257
258 return newvar;
259 }
260
261 static oberon_object_t *
262 oberon_define_type(oberon_scope_t * scope, char * name, oberon_type_t * type, int export)
263 {
264 oberon_object_t * id;
265 id = oberon_define_object(scope, name, OBERON_CLASS_TYPE, export, false, false);
266 id -> type = type;
267 oberon_generator_init_type(scope -> ctx, type);
268 return id;
269 }
270
271 // =======================================================================
272 // SCANER
273 // =======================================================================
274
275 static void
276 oberon_get_char(oberon_context_t * ctx)
277 {
278 if(ctx -> code[ctx -> code_index])
279 {
280 ctx -> code_index += 1;
281 ctx -> c = ctx -> code[ctx -> code_index];
282 }
283 }
284
285 static void
286 oberon_init_scaner(oberon_context_t * ctx, const char * code)
287 {
288 ctx -> code = code;
289 ctx -> code_index = 0;
290 ctx -> c = ctx -> code[ctx -> code_index];
291 }
292
293 static void
294 oberon_read_ident(oberon_context_t * ctx)
295 {
296 int len = 0;
297 int i = ctx -> code_index;
298
299 int c = ctx -> code[i];
300 while(isalnum(c))
301 {
302 i += 1;
303 len += 1;
304 c = ctx -> code[i];
305 }
306
307 char * ident = malloc(len + 1);
308 memcpy(ident, &ctx->code[ctx->code_index], len);
309 ident[len] = 0;
310
311 ctx -> code_index = i;
312 ctx -> c = ctx -> code[i];
313 ctx -> string = ident;
314 ctx -> token = IDENT;
315
316 if(strcmp(ident, "MODULE") == 0)
317 {
318 ctx -> token = MODULE;
319 }
320 else if(strcmp(ident, "END") == 0)
321 {
322 ctx -> token = END;
323 }
324 else if(strcmp(ident, "VAR") == 0)
325 {
326 ctx -> token = VAR;
327 }
328 else if(strcmp(ident, "BEGIN") == 0)
329 {
330 ctx -> token = BEGIN;
331 }
332 else if(strcmp(ident, "TRUE") == 0)
333 {
334 ctx -> token = TRUE;
335 }
336 else if(strcmp(ident, "FALSE") == 0)
337 {
338 ctx -> token = FALSE;
339 }
340 else if(strcmp(ident, "OR") == 0)
341 {
342 ctx -> token = OR;
343 }
344 else if(strcmp(ident, "DIV") == 0)
345 {
346 ctx -> token = DIV;
347 }
348 else if(strcmp(ident, "MOD") == 0)
349 {
350 ctx -> token = MOD;
351 }
352 else if(strcmp(ident, "PROCEDURE") == 0)
353 {
354 ctx -> token = PROCEDURE;
355 }
356 else if(strcmp(ident, "RETURN") == 0)
357 {
358 ctx -> token = RETURN;
359 }
360 else if(strcmp(ident, "CONST") == 0)
361 {
362 ctx -> token = CONST;
363 }
364 else if(strcmp(ident, "TYPE") == 0)
365 {
366 ctx -> token = TYPE;
367 }
368 else if(strcmp(ident, "ARRAY") == 0)
369 {
370 ctx -> token = ARRAY;
371 }
372 else if(strcmp(ident, "OF") == 0)
373 {
374 ctx -> token = OF;
375 }
376 else if(strcmp(ident, "RECORD") == 0)
377 {
378 ctx -> token = RECORD;
379 }
380 else if(strcmp(ident, "POINTER") == 0)
381 {
382 ctx -> token = POINTER;
383 }
384 else if(strcmp(ident, "TO") == 0)
385 {
386 ctx -> token = TO;
387 }
388 else if(strcmp(ident, "NIL") == 0)
389 {
390 ctx -> token = NIL;
391 }
392 else if(strcmp(ident, "IMPORT") == 0)
393 {
394 ctx -> token = IMPORT;
395 }
396 else if(strcmp(ident, "IN") == 0)
397 {
398 ctx -> token = IN;
399 }
400 else if(strcmp(ident, "IS") == 0)
401 {
402 ctx -> token = IS;
403 }
404 else if(strcmp(ident, "IF") == 0)
405 {
406 ctx -> token = IF;
407 }
408 else if(strcmp(ident, "THEN") == 0)
409 {
410 ctx -> token = THEN;
411 }
412 else if(strcmp(ident, "ELSE") == 0)
413 {
414 ctx -> token = ELSE;
415 }
416 else if(strcmp(ident, "ELSIF") == 0)
417 {
418 ctx -> token = ELSIF;
419 }
420 else if(strcmp(ident, "WHILE") == 0)
421 {
422 ctx -> token = WHILE;
423 }
424 else if(strcmp(ident, "DO") == 0)
425 {
426 ctx -> token = DO;
427 }
428 else if(strcmp(ident, "REPEAT") == 0)
429 {
430 ctx -> token = REPEAT;
431 }
432 else if(strcmp(ident, "UNTIL") == 0)
433 {
434 ctx -> token = UNTIL;
435 }
436 else if(strcmp(ident, "FOR") == 0)
437 {
438 ctx -> token = FOR;
439 }
440 else if(strcmp(ident, "BY") == 0)
441 {
442 ctx -> token = BY;
443 }
444 else if(strcmp(ident, "LOOP") == 0)
445 {
446 ctx -> token = LOOP;
447 }
448 else if(strcmp(ident, "EXIT") == 0)
449 {
450 ctx -> token = EXIT;
451 }
452 }
453
454 static void
455 oberon_read_number(oberon_context_t * ctx)
456 {
457 long integer;
458 double real;
459 char * ident;
460 int start_i;
461 int exp_i;
462 int end_i;
463
464 /*
465 * mode = 0 == DEC
466 * mode = 1 == HEX
467 * mode = 2 == REAL
468 * mode = 3 == LONGREAL
469 * mode = 4 == CHAR
470 */
471 int mode = 0;
472 start_i = ctx -> code_index;
473
474 while(isdigit(ctx -> c))
475 {
476 oberon_get_char(ctx);
477 }
478
479 end_i = ctx -> code_index;
480
481 if(isxdigit(ctx -> c))
482 {
483 mode = 1;
484 while(isxdigit(ctx -> c))
485 {
486 oberon_get_char(ctx);
487 }
488
489 end_i = ctx -> code_index;
490
491 if(ctx -> c == 'H')
492 {
493 mode = 1;
494 oberon_get_char(ctx);
495 }
496 else if(ctx -> c == 'X')
497 {
498 mode = 4;
499 oberon_get_char(ctx);
500 }
501 else
502 {
503 oberon_error(ctx, "invalid hex number");
504 }
505 }
506 else if(ctx -> c == '.')
507 {
508 mode = 2;
509 oberon_get_char(ctx);
510
511 while(isdigit(ctx -> c))
512 {
513 oberon_get_char(ctx);
514 }
515
516 if(ctx -> c == 'E' || ctx -> c == 'D')
517 {
518 exp_i = ctx -> code_index;
519
520 if(ctx -> c == 'D')
521 {
522 mode = 3;
523 }
524
525 oberon_get_char(ctx);
526
527 if(ctx -> c == '+' || ctx -> c == '-')
528 {
529 oberon_get_char(ctx);
530 }
531
532 while(isdigit(ctx -> c))
533 {
534 oberon_get_char(ctx);
535 }
536
537 }
538
539 end_i = ctx -> code_index;
540 }
541
542 if(mode == 0)
543 {
544 if(ctx -> c == 'H')
545 {
546 mode = 1;
547 oberon_get_char(ctx);
548 }
549 else if(ctx -> c == 'X')
550 {
551 mode = 4;
552 oberon_get_char(ctx);
553 }
554 }
555
556 int len = end_i - start_i;
557 ident = malloc(len + 1);
558 memcpy(ident, &ctx -> code[start_i], len);
559 ident[len] = 0;
560
561 ctx -> longmode = false;
562 if(mode == 3)
563 {
564 int i = exp_i - start_i;
565 ident[i] = 'E';
566 ctx -> longmode = true;
567 }
568
569 switch(mode)
570 {
571 case 0:
572 integer = atol(ident);
573 real = integer;
574 ctx -> token = INTEGER;
575 break;
576 case 1:
577 sscanf(ident, "%lx", &integer);
578 real = integer;
579 ctx -> token = INTEGER;
580 break;
581 case 2:
582 case 3:
583 sscanf(ident, "%lf", &real);
584 ctx -> token = REAL;
585 break;
586 case 4:
587 sscanf(ident, "%lx", &integer);
588 real = integer;
589 ctx -> token = CHAR;
590 break;
591 default:
592 oberon_error(ctx, "oberon_read_number: wat");
593 break;
594 }
595
596 ctx -> string = ident;
597 ctx -> integer = integer;
598 ctx -> real = real;
599 }
600
601 static void
602 oberon_skip_space(oberon_context_t * ctx)
603 {
604 while(isspace(ctx -> c))
605 {
606 oberon_get_char(ctx);
607 }
608 }
609
610 static void
611 oberon_read_comment(oberon_context_t * ctx)
612 {
613 int nesting = 1;
614 while(nesting >= 1)
615 {
616 if(ctx -> c == '(')
617 {
618 oberon_get_char(ctx);
619 if(ctx -> c == '*')
620 {
621 oberon_get_char(ctx);
622 nesting += 1;
623 }
624 }
625 else if(ctx -> c == '*')
626 {
627 oberon_get_char(ctx);
628 if(ctx -> c == ')')
629 {
630 oberon_get_char(ctx);
631 nesting -= 1;
632 }
633 }
634 else if(ctx -> c == 0)
635 {
636 oberon_error(ctx, "unterminated comment");
637 }
638 else
639 {
640 oberon_get_char(ctx);
641 }
642 }
643 }
644
645 static void oberon_read_string(oberon_context_t * ctx)
646 {
647 int c = ctx -> c;
648 oberon_get_char(ctx);
649
650 int start = ctx -> code_index;
651
652 while(ctx -> c != 0 && ctx -> c != c)
653 {
654 oberon_get_char(ctx);
655 }
656
657 if(ctx -> c == 0)
658 {
659 oberon_error(ctx, "unterminated string");
660 }
661
662 int end = ctx -> code_index;
663
664 oberon_get_char(ctx);
665
666 char * string = calloc(1, end - start + 1);
667 strncpy(string, &ctx -> code[start], end - start);
668
669 ctx -> token = STRING;
670 ctx -> string = string;
671
672 printf("oberon_read_string: string ((%s))\n", string);
673 }
674
675 static void oberon_read_token(oberon_context_t * ctx);
676
677 static void
678 oberon_read_symbol(oberon_context_t * ctx)
679 {
680 int c = ctx -> c;
681 switch(c)
682 {
683 case 0:
684 ctx -> token = EOF_;
685 break;
686 case ';':
687 ctx -> token = SEMICOLON;
688 oberon_get_char(ctx);
689 break;
690 case ':':
691 ctx -> token = COLON;
692 oberon_get_char(ctx);
693 if(ctx -> c == '=')
694 {
695 ctx -> token = ASSIGN;
696 oberon_get_char(ctx);
697 }
698 break;
699 case '.':
700 ctx -> token = DOT;
701 oberon_get_char(ctx);
702 break;
703 case '(':
704 ctx -> token = LPAREN;
705 oberon_get_char(ctx);
706 if(ctx -> c == '*')
707 {
708 oberon_get_char(ctx);
709 oberon_read_comment(ctx);
710 oberon_read_token(ctx);
711 }
712 break;
713 case ')':
714 ctx -> token = RPAREN;
715 oberon_get_char(ctx);
716 break;
717 case '=':
718 ctx -> token = EQUAL;
719 oberon_get_char(ctx);
720 break;
721 case '#':
722 ctx -> token = NEQ;
723 oberon_get_char(ctx);
724 break;
725 case '<':
726 ctx -> token = LESS;
727 oberon_get_char(ctx);
728 if(ctx -> c == '=')
729 {
730 ctx -> token = LEQ;
731 oberon_get_char(ctx);
732 }
733 break;
734 case '>':
735 ctx -> token = GREAT;
736 oberon_get_char(ctx);
737 if(ctx -> c == '=')
738 {
739 ctx -> token = GEQ;
740 oberon_get_char(ctx);
741 }
742 break;
743 case '+':
744 ctx -> token = PLUS;
745 oberon_get_char(ctx);
746 break;
747 case '-':
748 ctx -> token = MINUS;
749 oberon_get_char(ctx);
750 break;
751 case '*':
752 ctx -> token = STAR;
753 oberon_get_char(ctx);
754 if(ctx -> c == ')')
755 {
756 oberon_get_char(ctx);
757 oberon_error(ctx, "unstarted comment");
758 }
759 break;
760 case '/':
761 ctx -> token = SLASH;
762 oberon_get_char(ctx);
763 break;
764 case '&':
765 ctx -> token = AND;
766 oberon_get_char(ctx);
767 break;
768 case '~':
769 ctx -> token = NOT;
770 oberon_get_char(ctx);
771 break;
772 case ',':
773 ctx -> token = COMMA;
774 oberon_get_char(ctx);
775 break;
776 case '[':
777 ctx -> token = LBRACE;
778 oberon_get_char(ctx);
779 break;
780 case ']':
781 ctx -> token = RBRACE;
782 oberon_get_char(ctx);
783 break;
784 case '^':
785 ctx -> token = UPARROW;
786 oberon_get_char(ctx);
787 break;
788 case '"':
789 oberon_read_string(ctx);
790 break;
791 case '\'':
792 oberon_read_string(ctx);
793 break;
794 default:
795 oberon_error(ctx, "invalid char %c", ctx -> c);
796 break;
797 }
798 }
799
800 static void
801 oberon_read_token(oberon_context_t * ctx)
802 {
803 oberon_skip_space(ctx);
804
805 int c = ctx -> c;
806 if(isalpha(c))
807 {
808 oberon_read_ident(ctx);
809 }
810 else if(isdigit(c))
811 {
812 oberon_read_number(ctx);
813 }
814 else
815 {
816 oberon_read_symbol(ctx);
817 }
818 }
819
820 // =======================================================================
821 // EXPRESSION
822 // =======================================================================
823
824 static void oberon_expect_token(oberon_context_t * ctx, int token);
825 static oberon_expr_t * oberon_expr(oberon_context_t * ctx);
826 static void oberon_assert_token(oberon_context_t * ctx, int token);
827 static char * oberon_assert_ident(oberon_context_t * ctx);
828 static void oberon_type(oberon_context_t * ctx, oberon_type_t ** type);
829 static oberon_item_t * oberon_const_expr(oberon_context_t * ctx);
830 static oberon_expr_t * oberno_make_dereferencing(oberon_context_t * ctx, oberon_expr_t * expr);
831
832 static oberon_expr_t *
833 oberon_new_operator(int op, oberon_type_t * result, oberon_expr_t * left, oberon_expr_t * right)
834 {
835 oberon_oper_t * operator;
836 operator = malloc(sizeof *operator);
837 memset(operator, 0, sizeof *operator);
838
839 operator -> is_item = 0;
840 operator -> result = result;
841 operator -> read_only = 1;
842 operator -> op = op;
843 operator -> left = left;
844 operator -> right = right;
845
846 return (oberon_expr_t *) operator;
847 }
848
849 static oberon_expr_t *
850 oberon_new_item(int mode, oberon_type_t * result, int read_only)
851 {
852 oberon_item_t * item;
853 item = malloc(sizeof *item);
854 memset(item, 0, sizeof *item);
855
856 item -> is_item = 1;
857 item -> result = result;
858 item -> read_only = read_only;
859 item -> mode = mode;
860
861 return (oberon_expr_t *)item;
862 }
863
864 static oberon_expr_t *
865 oberon_make_unary_op(oberon_context_t * ctx, int token, oberon_expr_t * a)
866 {
867 oberon_expr_t * expr;
868 oberon_type_t * result;
869
870 result = a -> result;
871
872 if(token == MINUS)
873 {
874 if(result -> class != OBERON_TYPE_INTEGER)
875 {
876 oberon_error(ctx, "incompatible operator type");
877 }
878
879 expr = oberon_new_operator(OP_UNARY_MINUS, result, a, NULL);
880 }
881 else if(token == NOT)
882 {
883 if(result -> class != OBERON_TYPE_BOOLEAN)
884 {
885 oberon_error(ctx, "incompatible operator type");
886 }
887
888 expr = oberon_new_operator(OP_LOGIC_NOT, result, a, NULL);
889 }
890 else
891 {
892 oberon_error(ctx, "oberon_make_unary_op: wat");
893 }
894
895 return expr;
896 }
897
898 static void
899 oberon_expr_list(oberon_context_t * ctx, int * num_expr, oberon_expr_t ** first, int const_expr)
900 {
901 oberon_expr_t * last;
902
903 *num_expr = 1;
904 if(const_expr)
905 {
906 *first = last = (oberon_expr_t *) oberon_const_expr(ctx);
907 }
908 else
909 {
910 *first = last = oberon_expr(ctx);
911 }
912 while(ctx -> token == COMMA)
913 {
914 oberon_assert_token(ctx, COMMA);
915 oberon_expr_t * current;
916
917 if(const_expr)
918 {
919 current = (oberon_expr_t *) oberon_const_expr(ctx);
920 }
921 else
922 {
923 current = oberon_expr(ctx);
924 }
925
926 last -> next = current;
927 last = current;
928 *num_expr += 1;
929 }
930 }
931
932 static oberon_expr_t *
933 oberon_cast_expr(oberon_context_t * ctx, oberon_expr_t * expr, oberon_type_t * pref)
934 {
935 return oberon_new_operator(OP_CAST, pref, expr, NULL);
936 }
937
938 static oberon_expr_t *
939 oberno_make_record_cast(oberon_context_t * ctx, oberon_expr_t * expr, oberon_type_t * rec)
940 {
941 oberon_type_t * from = expr -> result;
942 oberon_type_t * to = rec;
943
944 printf("oberno_make_record_cast: from class %i to class %i\n", from -> class, to -> class);
945
946 if(from -> class == OBERON_TYPE_POINTER && to -> class == OBERON_TYPE_POINTER)
947 {
948 printf("oberno_make_record_cast: pointers\n");
949 from = from -> base;
950 to = to -> base;
951 }
952
953 if(from -> class != OBERON_TYPE_RECORD || to -> class != OBERON_TYPE_RECORD)
954 {
955 oberon_error(ctx, "must be record type");
956 }
957
958 return oberon_cast_expr(ctx, expr, rec);
959 }
960
961 static oberon_type_t *
962 oberon_get_equal_expr_type(oberon_context_t * ctx, oberon_type_t * a, oberon_type_t * b)
963 {
964 oberon_type_t * result;
965 if(a -> class == OBERON_TYPE_REAL && b -> class == OBERON_TYPE_INTEGER)
966 {
967 result = a;
968 }
969 else if(b -> class == OBERON_TYPE_REAL && a -> class == OBERON_TYPE_INTEGER)
970 {
971 result = b;
972 }
973 else if(a -> class != b -> class)
974 {
975 oberon_error(ctx, "oberon_get_equal_expr_type: incompatible types");
976 }
977 else if(a -> size > b -> size)
978 {
979 result = a;
980 }
981 else
982 {
983 result = b;
984 }
985
986 return result;
987 }
988
989 static void
990 oberon_check_record_compatibility(oberon_context_t * ctx, oberon_type_t * from, oberon_type_t * to)
991 {
992 if(from -> class == OBERON_TYPE_POINTER && to -> class == OBERON_TYPE_POINTER)
993 {
994 from = from -> base;
995 to = to -> base;
996 }
997
998 if(from -> class != OBERON_TYPE_RECORD || to -> class != OBERON_TYPE_RECORD)
999 {
1000 oberon_error(ctx, "not a record");
1001 }
1002
1003 oberon_type_t * t = from;
1004 while(t != NULL && t != to)
1005 {
1006 t = t -> base;
1007 }
1008
1009 if(t == NULL)
1010 {
1011 oberon_error(ctx, "incompatible record types");
1012 }
1013 }
1014
1015 static void
1016 oberon_check_dst(oberon_context_t * ctx, oberon_expr_t * dst)
1017 {
1018 if(dst -> is_item == false)
1019 {
1020 oberon_error(ctx, "not variable");
1021 }
1022
1023 switch(dst -> item.mode)
1024 {
1025 case MODE_VAR:
1026 case MODE_CALL:
1027 case MODE_INDEX:
1028 case MODE_FIELD:
1029 case MODE_DEREF:
1030 case MODE_NEW:
1031 /* accept */
1032 break;
1033 default:
1034 oberon_error(ctx, "not variable");
1035 break;
1036 }
1037 }
1038
1039 static void
1040 oberon_check_src(oberon_context_t * ctx, oberon_expr_t * src)
1041 {
1042 if(src -> is_item)
1043 {
1044 if(src -> item.mode == MODE_TYPE)
1045 {
1046 oberon_error(ctx, "not variable");
1047 }
1048 }
1049 }
1050
1051 static oberon_expr_t *
1052 oberon_autocast_to(oberon_context_t * ctx, oberon_expr_t * expr, oberon_type_t * pref)
1053 {
1054 // Допускается:
1055 // Если классы типов равны
1056 // Если INTEGER переводится в REAL
1057 // Есди STRING переводится в ARRAY OF CHAR
1058
1059 oberon_check_src(ctx, expr);
1060
1061 bool error = false;
1062 if(pref -> class != expr -> result -> class)
1063 {
1064 printf("expr class %i\n", expr -> result -> class);
1065 printf("pref class %i\n", pref -> class);
1066
1067 if(expr -> result -> class == OBERON_TYPE_STRING)
1068 {
1069 if(pref -> class == OBERON_TYPE_ARRAY)
1070 {
1071 if(pref -> base -> class != OBERON_TYPE_CHAR)
1072 {
1073 error = true;
1074 }
1075 }
1076 else
1077 {
1078 error = true;
1079 }
1080 }
1081 else if(expr -> result -> class == OBERON_TYPE_INTEGER)
1082 {
1083 if(pref -> class != OBERON_TYPE_REAL)
1084 {
1085 error = true;
1086 }
1087 }
1088 else
1089 {
1090 error = true;
1091 }
1092 }
1093
1094 if(error)
1095 {
1096 oberon_error(ctx, "oberon_autocast_to: incompatible types");
1097 }
1098
1099 if(pref -> class == OBERON_TYPE_INTEGER || pref -> class == OBERON_TYPE_REAL)
1100 {
1101 if(expr -> result -> size > pref -> size)
1102 {
1103 oberon_error(ctx, "incompatible size");
1104 }
1105 else
1106 {
1107 expr = oberon_cast_expr(ctx, expr, pref);
1108 }
1109 }
1110 else if(pref -> class == OBERON_TYPE_RECORD)
1111 {
1112 oberon_check_record_compatibility(ctx, expr -> result, pref);
1113 expr = oberno_make_record_cast(ctx, expr, pref);
1114 }
1115 else if(pref -> class == OBERON_TYPE_POINTER)
1116 {
1117 assert(pref -> base);
1118 if(expr -> result -> base -> class == OBERON_TYPE_RECORD)
1119 {
1120 oberon_check_record_compatibility(ctx, expr -> result, pref);
1121 expr = oberno_make_record_cast(ctx, expr, pref);
1122 }
1123 else if(expr -> result -> base != pref -> base)
1124 {
1125 if(expr -> result -> base -> class != OBERON_TYPE_VOID)
1126 {
1127 oberon_error(ctx, "incompatible pointer types");
1128 }
1129 }
1130 }
1131
1132 return expr;
1133 }
1134
1135 static void
1136 oberon_autocast_binary_op(oberon_context_t * ctx, oberon_expr_t ** ea, oberon_expr_t ** eb)
1137 {
1138 oberon_type_t * a = (*ea) -> result;
1139 oberon_type_t * b = (*eb) -> result;
1140 oberon_type_t * preq = oberon_get_equal_expr_type(ctx, a, b);
1141 *ea = oberon_autocast_to(ctx, *ea, preq);
1142 *eb = oberon_autocast_to(ctx, *eb, preq);
1143 }
1144
1145 static void
1146 oberon_autocast_call(oberon_context_t * ctx, oberon_item_t * desig)
1147 {
1148 if(desig -> mode != MODE_CALL)
1149 {
1150 oberon_error(ctx, "expected mode CALL");
1151 }
1152
1153 oberon_type_t * fn = desig -> parent -> result;
1154 int num_args = desig -> num_args;
1155 int num_decl = fn -> num_decl;
1156
1157 if(num_args < num_decl)
1158 {
1159 oberon_error(ctx, "too few arguments");
1160 }
1161 else if(num_args > num_decl)
1162 {
1163 oberon_error(ctx, "too many arguments");
1164 }
1165
1166 /* Делаем проверку на запись и делаем автокаст */
1167 oberon_expr_t * casted[num_args];
1168 oberon_expr_t * arg = desig -> args;
1169 oberon_object_t * param = fn -> decl;
1170 for(int i = 0; i < num_args; i++)
1171 {
1172 if(param -> class == OBERON_CLASS_VAR_PARAM)
1173 {
1174 if(arg -> read_only)
1175 {
1176 oberon_error(ctx, "assign to read-only var");
1177 }
1178 }
1179
1180 casted[i] = oberon_autocast_to(ctx, arg, param -> type);
1181 arg = arg -> next;
1182 param = param -> next;
1183 }
1184
1185 /* Создаём новый список выражений */
1186 if(num_args > 0)
1187 {
1188 arg = casted[0];
1189 for(int i = 0; i < num_args - 1; i++)
1190 {
1191 casted[i] -> next = casted[i + 1];
1192 }
1193 desig -> args = arg;
1194 }
1195 }
1196
1197 static oberon_expr_t *
1198 oberon_make_call_func(oberon_context_t * ctx, oberon_item_t * item, int num_args, oberon_expr_t * list_args)
1199 {
1200 oberon_type_t * signature = item -> result;
1201 if(signature -> class != OBERON_TYPE_PROCEDURE)
1202 {
1203 oberon_error(ctx, "not a procedure");
1204 }
1205
1206 oberon_expr_t * call;
1207
1208 if(signature -> sysproc)
1209 {
1210 if(signature -> genfunc == NULL)
1211 {
1212 oberon_error(ctx, "not a function-procedure");
1213 }
1214
1215 call = signature -> genfunc(ctx, num_args, list_args);
1216 }
1217 else
1218 {
1219 if(signature -> base -> class == OBERON_TYPE_VOID)
1220 {
1221 oberon_error(ctx, "attempt to call procedure in expression");
1222 }
1223
1224 call = oberon_new_item(MODE_CALL, signature -> base, true);
1225 call -> item.parent = item;
1226 call -> item.num_args = num_args;
1227 call -> item.args = list_args;
1228 oberon_autocast_call(ctx, (oberon_item_t *) call);
1229 }
1230
1231 return call;
1232 }
1233
1234 static void
1235 oberon_make_call_proc(oberon_context_t * ctx, oberon_item_t * item, int num_args, oberon_expr_t * list_args)
1236 {
1237 oberon_type_t * signature = item -> result;
1238 if(signature -> class != OBERON_TYPE_PROCEDURE)
1239 {
1240 oberon_error(ctx, "not a procedure");
1241 }
1242
1243 oberon_expr_t * call;
1244
1245 if(signature -> sysproc)
1246 {
1247 if(signature -> genproc == NULL)
1248 {
1249 oberon_error(ctx, "not a procedure");
1250 }
1251
1252 signature -> genproc(ctx, num_args, list_args);
1253 }
1254 else
1255 {
1256 if(signature -> base -> class != OBERON_TYPE_VOID)
1257 {
1258 oberon_error(ctx, "attempt to call function as non-typed procedure");
1259 }
1260
1261 call = oberon_new_item(MODE_CALL, signature -> base, true);
1262 call -> item.parent = item;
1263 call -> item.num_args = num_args;
1264 call -> item.args = list_args;
1265 oberon_autocast_call(ctx, (oberon_item_t *) call);
1266 oberon_generate_call_proc(ctx, call);
1267 }
1268 }
1269
1270 #define ISEXPR(x) \
1271 (((x) == PLUS) \
1272 || ((x) == MINUS) \
1273 || ((x) == IDENT) \
1274 || ((x) == INTEGER) \
1275 || ((x) == REAL) \
1276 || ((x) == CHAR) \
1277 || ((x) == STRING) \
1278 || ((x) == NIL) \
1279 || ((x) == LPAREN) \
1280 || ((x) == NOT) \
1281 || ((x) == TRUE) \
1282 || ((x) == FALSE))
1283
1284 static oberon_expr_t *
1285 oberno_make_dereferencing(oberon_context_t * ctx, oberon_expr_t * expr)
1286 {
1287 printf("oberno_make_dereferencing\n");
1288 if(expr -> result -> class != OBERON_TYPE_POINTER)
1289 {
1290 oberon_error(ctx, "not a pointer");
1291 }
1292
1293 assert(expr -> is_item);
1294
1295 oberon_expr_t * selector;
1296 selector = oberon_new_item(MODE_DEREF, expr -> result -> base, expr -> read_only);
1297 selector -> item.parent = (oberon_item_t *) expr;
1298
1299 return selector;
1300 }
1301
1302 static oberon_expr_t *
1303 oberon_make_array_selector(oberon_context_t * ctx, oberon_expr_t * desig, oberon_expr_t * index)
1304 {
1305 if(desig -> result -> class == OBERON_TYPE_POINTER)
1306 {
1307 desig = oberno_make_dereferencing(ctx, desig);
1308 }
1309
1310 assert(desig -> is_item);
1311
1312 if(desig -> result -> class != OBERON_TYPE_ARRAY)
1313 {
1314 oberon_error(ctx, "not array");
1315 }
1316
1317 oberon_type_t * base;
1318 base = desig -> result -> base;
1319
1320 if(index -> result -> class != OBERON_TYPE_INTEGER)
1321 {
1322 oberon_error(ctx, "index must be integer");
1323 }
1324
1325 // Статическая проверка границ массива
1326 if(desig -> result -> size != 0)
1327 {
1328 if(index -> is_item)
1329 {
1330 if(index -> item.mode == MODE_INTEGER)
1331 {
1332 int arr_size = desig -> result -> size;
1333 int index_int = index -> item.integer;
1334 if(index_int < 0 || index_int > arr_size - 1)
1335 {
1336 oberon_error(ctx, "not in range (dimension size 0..%i)", arr_size - 1);
1337 }
1338 }
1339 }
1340 }
1341
1342 oberon_expr_t * selector;
1343 selector = oberon_new_item(MODE_INDEX, base, desig -> read_only);
1344 selector -> item.parent = (oberon_item_t *) desig;
1345 selector -> item.num_args = 1;
1346 selector -> item.args = index;
1347
1348 return selector;
1349 }
1350
1351 static oberon_expr_t *
1352 oberon_make_record_selector(oberon_context_t * ctx, oberon_expr_t * expr, char * name)
1353 {
1354 if(expr -> result -> class == OBERON_TYPE_POINTER)
1355 {
1356 expr = oberno_make_dereferencing(ctx, expr);
1357 }
1358
1359 assert(expr -> is_item);
1360
1361 if(expr -> result -> class != OBERON_TYPE_RECORD)
1362 {
1363 oberon_error(ctx, "not record");
1364 }
1365
1366 oberon_type_t * rec = expr -> result;
1367
1368 oberon_object_t * field;
1369 field = oberon_find_object(rec -> scope, name, true);
1370
1371 if(field -> export == 0)
1372 {
1373 if(field -> module != ctx -> mod)
1374 {
1375 oberon_error(ctx, "field not exported");
1376 }
1377 }
1378
1379 int read_only = 0;
1380 if(field -> read_only)
1381 {
1382 if(field -> module != ctx -> mod)
1383 {
1384 read_only = 1;
1385 }
1386 }
1387
1388 oberon_expr_t * selector;
1389 selector = oberon_new_item(MODE_FIELD, field -> type, read_only);
1390 selector -> item.var = field;
1391 selector -> item.parent = (oberon_item_t *) expr;
1392
1393 return selector;
1394 }
1395
1396 #define ISSELECTOR(x) \
1397 (((x) == LBRACE) \
1398 || ((x) == DOT) \
1399 || ((x) == UPARROW) \
1400 || ((x) == LPAREN))
1401
1402 static oberon_object_t *
1403 oberon_qualident(oberon_context_t * ctx, char ** xname, int check)
1404 {
1405 char * name;
1406 oberon_object_t * x;
1407
1408 name = oberon_assert_ident(ctx);
1409 x = oberon_find_object(ctx -> decl, name, check);
1410
1411 if(x != NULL)
1412 {
1413 if(x -> class == OBERON_CLASS_MODULE)
1414 {
1415 oberon_assert_token(ctx, DOT);
1416 name = oberon_assert_ident(ctx);
1417 /* Наличие объектов в левых модулях всегда проверяется */
1418 x = oberon_find_object(x -> module -> decl, name, 1);
1419
1420 if(x -> export == 0)
1421 {
1422 oberon_error(ctx, "not exported");
1423 }
1424 }
1425 }
1426
1427 if(xname)
1428 {
1429 *xname = name;
1430 }
1431
1432 return x;
1433 }
1434
1435 static oberon_expr_t *
1436 oberon_ident_item(oberon_context_t * ctx, char * name)
1437 {
1438 bool read_only;
1439 oberon_object_t * x;
1440 oberon_expr_t * expr;
1441
1442 x = oberon_find_object(ctx -> decl, name, true);
1443
1444 read_only = false;
1445 if(x -> class == OBERON_CLASS_CONST || x -> class == OBERON_CLASS_PROC)
1446 {
1447 read_only = true;
1448 }
1449
1450 expr = oberon_new_item(MODE_VAR, x -> type, read_only);
1451 expr -> item.var = x;
1452 return expr;
1453 }
1454
1455 static oberon_expr_t *
1456 oberon_designator(oberon_context_t * ctx)
1457 {
1458 char * name;
1459 oberon_object_t * var;
1460 oberon_expr_t * expr;
1461
1462 var = oberon_qualident(ctx, NULL, 1);
1463
1464 int read_only = 0;
1465 if(var -> read_only)
1466 {
1467 if(var -> module != ctx -> mod)
1468 {
1469 read_only = 1;
1470 }
1471 }
1472
1473 switch(var -> class)
1474 {
1475 case OBERON_CLASS_CONST:
1476 // TODO copy value
1477 expr = (oberon_expr_t *) var -> value;
1478 break;
1479 case OBERON_CLASS_TYPE:
1480 expr = oberon_new_item(MODE_TYPE, var -> type, read_only);
1481 break;
1482 case OBERON_CLASS_VAR:
1483 case OBERON_CLASS_VAR_PARAM:
1484 case OBERON_CLASS_PARAM:
1485 expr = oberon_new_item(MODE_VAR, var -> type, read_only);
1486 break;
1487 case OBERON_CLASS_PROC:
1488 expr = oberon_new_item(MODE_VAR, var -> type, true);
1489 break;
1490 default:
1491 oberon_error(ctx, "invalid designator");
1492 break;
1493 }
1494 expr -> item.var = var;
1495
1496 while(expr -> result -> class != OBERON_TYPE_PROCEDURE && ISSELECTOR(ctx -> token))
1497 {
1498 switch(ctx -> token)
1499 {
1500 case DOT:
1501 oberon_assert_token(ctx, DOT);
1502 name = oberon_assert_ident(ctx);
1503 expr = oberon_make_record_selector(ctx, expr, name);
1504 break;
1505 case LBRACE:
1506 oberon_assert_token(ctx, LBRACE);
1507 int num_indexes = 0;
1508 oberon_expr_t * indexes = NULL;
1509 oberon_expr_list(ctx, &num_indexes, &indexes, 0);
1510 oberon_assert_token(ctx, RBRACE);
1511
1512 for(int i = 0; i < num_indexes; i++)
1513 {
1514 expr = oberon_make_array_selector(ctx, expr, indexes);
1515 indexes = indexes -> next;
1516 }
1517 break;
1518 case UPARROW:
1519 oberon_assert_token(ctx, UPARROW);
1520 expr = oberno_make_dereferencing(ctx, expr);
1521 break;
1522 case LPAREN:
1523 oberon_assert_token(ctx, LPAREN);
1524 oberon_object_t * objtype = oberon_qualident(ctx, NULL, 1);
1525 if(objtype -> class != OBERON_CLASS_TYPE)
1526 {
1527 oberon_error(ctx, "must be type");
1528 }
1529 oberon_assert_token(ctx, RPAREN);
1530 expr = oberno_make_record_cast(ctx, expr, objtype -> type);
1531 break;
1532 default:
1533 oberon_error(ctx, "oberon_designator: wat");
1534 break;
1535 }
1536 }
1537
1538 return expr;
1539 }
1540
1541 static oberon_expr_t *
1542 oberon_opt_func_parens(oberon_context_t * ctx, oberon_expr_t * expr)
1543 {
1544 /* Если есть скобки - значит вызов. Если нет, то передаём указатель. */
1545 if(ctx -> token == LPAREN)
1546 {
1547 oberon_assert_token(ctx, LPAREN);
1548
1549 int num_args = 0;
1550 oberon_expr_t * arguments = NULL;
1551
1552 if(ISEXPR(ctx -> token))
1553 {
1554 oberon_expr_list(ctx, &num_args, &arguments, 0);
1555 }
1556
1557 assert(expr -> is_item == 1);
1558 expr = oberon_make_call_func(ctx, (oberon_item_t *) expr, num_args, arguments);
1559
1560 oberon_assert_token(ctx, RPAREN);
1561 }
1562
1563 return expr;
1564 }
1565
1566 static void
1567 oberon_opt_proc_parens(oberon_context_t * ctx, oberon_expr_t * expr)
1568 {
1569 assert(expr -> is_item);
1570
1571 int num_args = 0;
1572 oberon_expr_t * arguments = NULL;
1573
1574 if(ctx -> token == LPAREN)
1575 {
1576 oberon_assert_token(ctx, LPAREN);
1577
1578 if(ISEXPR(ctx -> token))
1579 {
1580 oberon_expr_list(ctx, &num_args, &arguments, 0);
1581 }
1582
1583 oberon_assert_token(ctx, RPAREN);
1584 }
1585
1586 /* Вызов происходит даже без скобок */
1587 oberon_make_call_proc(ctx, (oberon_item_t *) expr, num_args, arguments);
1588 }
1589
1590 static oberon_type_t *
1591 oberon_get_type_of_int_value(oberon_context_t * ctx, int64_t i)
1592 {
1593 if(i >= -128 && i <= 127)
1594 {
1595 return ctx -> byte_type;
1596 }
1597 else if(i >= -32768 && i <= 32767)
1598 {
1599 return ctx -> shortint_type;
1600 }
1601 else if(i >= -2147483648 && i <= 2147483647)
1602 {
1603 return ctx -> int_type;
1604 }
1605 else
1606 {
1607 return ctx -> longint_type;
1608 }
1609 }
1610
1611 static oberon_expr_t *
1612 oberon_integer_item(oberon_context_t * ctx, int64_t i)
1613 {
1614 oberon_expr_t * expr;
1615 oberon_type_t * result;
1616 result = oberon_get_type_of_int_value(ctx, i);
1617 expr = oberon_new_item(MODE_INTEGER, result, true);
1618 expr -> item.integer = i;
1619 return expr;
1620 }
1621
1622 static oberon_expr_t *
1623 oberon_factor(oberon_context_t * ctx)
1624 {
1625 oberon_expr_t * expr;
1626 oberon_type_t * result;
1627
1628 switch(ctx -> token)
1629 {
1630 case IDENT:
1631 expr = oberon_designator(ctx);
1632 expr = oberon_opt_func_parens(ctx, expr);
1633 break;
1634 case INTEGER:
1635 expr = oberon_integer_item(ctx, ctx -> integer);
1636 oberon_assert_token(ctx, INTEGER);
1637 break;
1638 case CHAR:
1639 result = ctx -> char_type;
1640 expr = oberon_new_item(MODE_CHAR, result, true);
1641 expr -> item.integer = ctx -> integer;
1642 oberon_assert_token(ctx, CHAR);
1643 break;
1644 case STRING:
1645 result = ctx -> string_type;
1646 expr = oberon_new_item(MODE_STRING, result, true);
1647 expr -> item.string = ctx -> string;
1648 oberon_assert_token(ctx, STRING);
1649 break;
1650 case REAL:
1651 result = (ctx -> longmode) ? (ctx -> longreal_type) : (ctx -> real_type);
1652 expr = oberon_new_item(MODE_REAL, result, 1);
1653 expr -> item.real = ctx -> real;
1654 oberon_assert_token(ctx, REAL);
1655 break;
1656 case TRUE:
1657 expr = oberon_new_item(MODE_BOOLEAN, ctx -> bool_type, true);
1658 expr -> item.boolean = true;
1659 oberon_assert_token(ctx, TRUE);
1660 break;
1661 case FALSE:
1662 expr = oberon_new_item(MODE_BOOLEAN, ctx -> bool_type, true);
1663 expr -> item.boolean = false;
1664 oberon_assert_token(ctx, FALSE);
1665 break;
1666 case LPAREN:
1667 oberon_assert_token(ctx, LPAREN);
1668 expr = oberon_expr(ctx);
1669 oberon_assert_token(ctx, RPAREN);
1670 break;
1671 case NOT:
1672 oberon_assert_token(ctx, NOT);
1673 expr = oberon_factor(ctx);
1674 expr = oberon_make_unary_op(ctx, NOT, expr);
1675 break;
1676 case NIL:
1677 oberon_assert_token(ctx, NIL);
1678 expr = oberon_new_item(MODE_NIL, ctx -> void_ptr_type, true);
1679 break;
1680 default:
1681 oberon_error(ctx, "invalid expression");
1682 }
1683
1684 return expr;
1685 }
1686
1687 #define ITMAKESBOOLEAN(x) \
1688 (((x) >= EQUAL && (x) <= GEQ) || ((x) == OR) || ((x) == AND))
1689
1690 #define ITUSEONLYINTEGER(x) \
1691 ((x) >= LESS && (x) <= GEQ)
1692
1693 #define ITUSEONLYBOOLEAN(x) \
1694 (((x) == OR) || ((x) == AND))
1695
1696 static void
1697 oberon_autocast_to_real(oberon_context_t * ctx, oberon_expr_t ** e)
1698 {
1699 oberon_expr_t * expr = *e;
1700 if(expr -> result -> class == OBERON_TYPE_INTEGER)
1701 {
1702 if(expr -> result -> size <= ctx -> real_type -> size)
1703 {
1704 *e = oberon_cast_expr(ctx, expr, ctx -> real_type);
1705 }
1706 else
1707 {
1708 *e = oberon_cast_expr(ctx, expr, ctx -> longreal_type);
1709 }
1710 }
1711 else if(expr -> result -> class != OBERON_TYPE_REAL)
1712 {
1713 oberon_error(ctx, "required numeric type");
1714 }
1715 }
1716
1717 static oberon_expr_t *
1718 oberon_make_bin_op(oberon_context_t * ctx, int token, oberon_expr_t * a, oberon_expr_t * b)
1719 {
1720 oberon_expr_t * expr;
1721 oberon_type_t * result;
1722
1723 if(token == IS)
1724 {
1725 oberon_type_t * v = a -> result;
1726 if(v -> class == OBERON_TYPE_POINTER)
1727 {
1728 v = v -> base;
1729 if(v -> class != OBERON_TYPE_RECORD)
1730 {
1731 oberon_error(ctx, "must be record");
1732 }
1733 }
1734 else if(v -> class != OBERON_TYPE_RECORD)
1735 {
1736 oberon_error(ctx, "must be record");
1737 }
1738
1739 if(b -> is_item == false || b -> item.mode != MODE_TYPE)
1740 {
1741 oberon_error(ctx, "requires type");
1742 }
1743
1744 oberon_type_t * t = b -> result;
1745 if(t -> class == OBERON_TYPE_POINTER)
1746 {
1747 t = t -> base;
1748 if(t -> class != OBERON_TYPE_RECORD)
1749 {
1750 oberon_error(ctx, "must be record");
1751 }
1752 }
1753 else if(t -> class != OBERON_TYPE_RECORD)
1754 {
1755 oberon_error(ctx, "must be record");
1756 }
1757
1758 result = ctx -> bool_type;
1759 expr = oberon_new_operator(OP_IS, result, a, b);
1760 }
1761 else if(ITMAKESBOOLEAN(token))
1762 {
1763 if(ITUSEONLYINTEGER(token))
1764 {
1765 if(a -> result -> class == OBERON_TYPE_INTEGER
1766 || b -> result -> class == OBERON_TYPE_INTEGER
1767 || a -> result -> class == OBERON_TYPE_REAL
1768 || b -> result -> class == OBERON_TYPE_REAL)
1769 {
1770 // accept
1771 }
1772 else
1773 {
1774 oberon_error(ctx, "used only with numeric types");
1775 }
1776 }
1777 else if(ITUSEONLYBOOLEAN(token))
1778 {
1779 if(a -> result -> class != OBERON_TYPE_BOOLEAN
1780 || b -> result -> class != OBERON_TYPE_BOOLEAN)
1781 {
1782 oberon_error(ctx, "used only with boolean type");
1783 }
1784 }
1785
1786 oberon_autocast_binary_op(ctx, &a, &b);
1787 result = ctx -> bool_type;
1788
1789 if(token == EQUAL)
1790 {
1791 expr = oberon_new_operator(OP_EQ, result, a, b);
1792 }
1793 else if(token == NEQ)
1794 {
1795 expr = oberon_new_operator(OP_NEQ, result, a, b);
1796 }
1797 else if(token == LESS)
1798 {
1799 expr = oberon_new_operator(OP_LSS, result, a, b);
1800 }
1801 else if(token == LEQ)
1802 {
1803 expr = oberon_new_operator(OP_LEQ, result, a, b);
1804 }
1805 else if(token == GREAT)
1806 {
1807 expr = oberon_new_operator(OP_GRT, result, a, b);
1808 }
1809 else if(token == GEQ)
1810 {
1811 expr = oberon_new_operator(OP_GEQ, result, a, b);
1812 }
1813 else if(token == OR)
1814 {
1815 expr = oberon_new_operator(OP_LOGIC_OR, result, a, b);
1816 }
1817 else if(token == AND)
1818 {
1819 expr = oberon_new_operator(OP_LOGIC_AND, result, a, b);
1820 }
1821 else
1822 {
1823 oberon_error(ctx, "oberon_make_bin_op: bool wat");
1824 }
1825 }
1826 else if(token == SLASH)
1827 {
1828 oberon_autocast_to_real(ctx, &a);
1829 oberon_autocast_to_real(ctx, &b);
1830 oberon_autocast_binary_op(ctx, &a, &b);
1831 expr = oberon_new_operator(OP_DIV, a -> result, a, b);
1832 }
1833 else if(token == DIV)
1834 {
1835 if(a -> result -> class != OBERON_TYPE_INTEGER
1836 || b -> result -> class != OBERON_TYPE_INTEGER)
1837 {
1838 oberon_error(ctx, "operator DIV requires integer type");
1839 }
1840
1841 oberon_autocast_binary_op(ctx, &a, &b);
1842 expr = oberon_new_operator(OP_DIV, a -> result, a, b);
1843 }
1844 else
1845 {
1846 oberon_autocast_binary_op(ctx, &a, &b);
1847
1848 if(token == PLUS)
1849 {
1850 expr = oberon_new_operator(OP_ADD, a -> result, a, b);
1851 }
1852 else if(token == MINUS)
1853 {
1854 expr = oberon_new_operator(OP_SUB, a -> result, a, b);
1855 }
1856 else if(token == STAR)
1857 {
1858 expr = oberon_new_operator(OP_MUL, a -> result, a, b);
1859 }
1860 else if(token == MOD)
1861 {
1862 expr = oberon_new_operator(OP_MOD, a -> result, a, b);
1863 }
1864 else
1865 {
1866 oberon_error(ctx, "oberon_make_bin_op: bin wat");
1867 }
1868 }
1869
1870 return expr;
1871 }
1872
1873 #define ISMULOP(x) \
1874 ((x) >= STAR && (x) <= AND)
1875
1876 static oberon_expr_t *
1877 oberon_term_expr(oberon_context_t * ctx)
1878 {
1879 oberon_expr_t * expr;
1880
1881 expr = oberon_factor(ctx);
1882 while(ISMULOP(ctx -> token))
1883 {
1884 int token = ctx -> token;
1885 oberon_read_token(ctx);
1886
1887 oberon_expr_t * inter = oberon_factor(ctx);
1888 expr = oberon_make_bin_op(ctx, token, expr, inter);
1889 }
1890
1891 return expr;
1892 }
1893
1894 #define ISADDOP(x) \
1895 ((x) >= PLUS && (x) <= OR)
1896
1897 static oberon_expr_t *
1898 oberon_simple_expr(oberon_context_t * ctx)
1899 {
1900 oberon_expr_t * expr;
1901
1902 int minus = 0;
1903 if(ctx -> token == PLUS)
1904 {
1905 minus = 0;
1906 oberon_assert_token(ctx, PLUS);
1907 }
1908 else if(ctx -> token == MINUS)
1909 {
1910 minus = 1;
1911 oberon_assert_token(ctx, MINUS);
1912 }
1913
1914 expr = oberon_term_expr(ctx);
1915
1916 if(minus)
1917 {
1918 expr = oberon_make_unary_op(ctx, MINUS, expr);
1919 }
1920
1921 while(ISADDOP(ctx -> token))
1922 {
1923 int token = ctx -> token;
1924 oberon_read_token(ctx);
1925
1926 oberon_expr_t * inter = oberon_term_expr(ctx);
1927 expr = oberon_make_bin_op(ctx, token, expr, inter);
1928 }
1929
1930 return expr;
1931 }
1932
1933 #define ISRELATION(x) \
1934 ((x) >= EQUAL && (x) <= IS)
1935
1936 static oberon_expr_t *
1937 oberon_expr(oberon_context_t * ctx)
1938 {
1939 oberon_expr_t * expr;
1940
1941 expr = oberon_simple_expr(ctx);
1942 while(ISRELATION(ctx -> token))
1943 {
1944 int token = ctx -> token;
1945 oberon_read_token(ctx);
1946
1947 oberon_expr_t * inter = oberon_simple_expr(ctx);
1948 expr = oberon_make_bin_op(ctx, token, expr, inter);
1949 }
1950
1951 return expr;
1952 }
1953
1954 static oberon_item_t *
1955 oberon_const_expr(oberon_context_t * ctx)
1956 {
1957 oberon_expr_t * expr;
1958 expr = oberon_expr(ctx);
1959
1960 if(expr -> is_item == 0)
1961 {
1962 oberon_error(ctx, "const expression are required");
1963 }
1964
1965 switch(expr -> item.mode)
1966 {
1967 case MODE_INTEGER:
1968 case MODE_BOOLEAN:
1969 case MODE_NIL:
1970 case MODE_REAL:
1971 case MODE_CHAR:
1972 case MODE_STRING:
1973 case MODE_TYPE:
1974 /* accept */
1975 break;
1976 default:
1977 oberon_error(ctx, "const expression are required");
1978 break;
1979 }
1980
1981 return (oberon_item_t *) expr;
1982 }
1983
1984 // =======================================================================
1985 // PARSER
1986 // =======================================================================
1987
1988 static void oberon_decl_seq(oberon_context_t * ctx);
1989 static void oberon_statement_seq(oberon_context_t * ctx);
1990 static void oberon_initialize_decl(oberon_context_t * ctx);
1991
1992 static void
1993 oberon_expect_token(oberon_context_t * ctx, int token)
1994 {
1995 if(ctx -> token != token)
1996 {
1997 oberon_error(ctx, "unexpected token %i (%i)", ctx -> token, token);
1998 }
1999 }
2000
2001 static void
2002 oberon_assert_token(oberon_context_t * ctx, int token)
2003 {
2004 oberon_expect_token(ctx, token);
2005 oberon_read_token(ctx);
2006 }
2007
2008 static char *
2009 oberon_assert_ident(oberon_context_t * ctx)
2010 {
2011 oberon_expect_token(ctx, IDENT);
2012 char * ident = ctx -> string;
2013 oberon_read_token(ctx);
2014 return ident;
2015 }
2016
2017 static void
2018 oberon_def(oberon_context_t * ctx, int * export, int * read_only)
2019 {
2020 switch(ctx -> token)
2021 {
2022 case STAR:
2023 oberon_assert_token(ctx, STAR);
2024 *export = 1;
2025 *read_only = 0;
2026 break;
2027 case MINUS:
2028 oberon_assert_token(ctx, MINUS);
2029 *export = 1;
2030 *read_only = 1;
2031 break;
2032 default:
2033 *export = 0;
2034 *read_only = 0;
2035 break;
2036 }
2037 }
2038
2039 static oberon_object_t *
2040 oberon_ident_def(oberon_context_t * ctx, int class, bool check_upscope)
2041 {
2042 char * name;
2043 int export;
2044 int read_only;
2045 oberon_object_t * x;
2046
2047 name = oberon_assert_ident(ctx);
2048 oberon_def(ctx, &export, &read_only);
2049
2050 x = oberon_define_object(ctx -> decl, name, class, export, read_only, check_upscope);
2051 return x;
2052 }
2053
2054 static void
2055 oberon_ident_list(oberon_context_t * ctx, int class, bool check_upscope, int * num, oberon_object_t ** list)
2056 {
2057 *num = 1;
2058 *list = oberon_ident_def(ctx, class, check_upscope);
2059 while(ctx -> token == COMMA)
2060 {
2061 oberon_assert_token(ctx, COMMA);
2062 oberon_ident_def(ctx, class, check_upscope);
2063 *num += 1;
2064 }
2065 }
2066
2067 static void
2068 oberon_var_decl(oberon_context_t * ctx)
2069 {
2070 int num;
2071 oberon_object_t * list;
2072 oberon_type_t * type;
2073 type = oberon_new_type_ptr(OBERON_TYPE_VOID);
2074
2075 oberon_ident_list(ctx, OBERON_CLASS_VAR, false, &num, &list);
2076 oberon_assert_token(ctx, COLON);
2077 oberon_type(ctx, &type);
2078
2079 oberon_object_t * var = list;
2080 for(int i = 0; i < num; i++)
2081 {
2082 var -> type = type;
2083 var = var -> next;
2084 }
2085 }
2086
2087 static oberon_object_t *
2088 oberon_fp_section(oberon_context_t * ctx, int * num_decl)
2089 {
2090 int class = OBERON_CLASS_PARAM;
2091 if(ctx -> token == VAR)
2092 {
2093 oberon_read_token(ctx);
2094 class = OBERON_CLASS_VAR_PARAM;
2095 }
2096
2097 int num;
2098 oberon_object_t * list;
2099 oberon_ident_list(ctx, class, false, &num, &list);
2100
2101 oberon_assert_token(ctx, COLON);
2102
2103 oberon_type_t * type;
2104 type = oberon_new_type_ptr(OBERON_TYPE_VOID);
2105 oberon_type(ctx, &type);
2106
2107 oberon_object_t * param = list;
2108 for(int i = 0; i < num; i++)
2109 {
2110 param -> type = type;
2111 param = param -> next;
2112 }
2113
2114 *num_decl += num;
2115 return list;
2116 }
2117
2118 #define ISFPSECTION \
2119 ((ctx -> token == VAR) || (ctx -> token == IDENT))
2120
2121 static void
2122 oberon_formal_pars(oberon_context_t * ctx, oberon_type_t * signature)
2123 {
2124 oberon_assert_token(ctx, LPAREN);
2125
2126 if(ISFPSECTION)
2127 {
2128 signature -> decl = oberon_fp_section(ctx, &signature -> num_decl);
2129 while(ctx -> token == SEMICOLON)
2130 {
2131 oberon_assert_token(ctx, SEMICOLON);
2132 oberon_fp_section(ctx, &signature -> num_decl);
2133 }
2134 }
2135
2136 oberon_assert_token(ctx, RPAREN);
2137
2138 if(ctx -> token == COLON)
2139 {
2140 oberon_assert_token(ctx, COLON);
2141
2142 oberon_object_t * typeobj;
2143 typeobj = oberon_qualident(ctx, NULL, 1);
2144 if(typeobj -> class != OBERON_CLASS_TYPE)
2145 {
2146 oberon_error(ctx, "function result is not type");
2147 }
2148 signature -> base = typeobj -> type;
2149 }
2150 }
2151
2152 static void
2153 oberon_opt_formal_pars(oberon_context_t * ctx, oberon_type_t ** type)
2154 {
2155 oberon_type_t * signature;
2156 signature = *type;
2157 signature -> class = OBERON_TYPE_PROCEDURE;
2158 signature -> num_decl = 0;
2159 signature -> base = ctx -> void_type;
2160 signature -> decl = NULL;
2161
2162 if(ctx -> token == LPAREN)
2163 {
2164 oberon_formal_pars(ctx, signature);
2165 }
2166 }
2167
2168 static void
2169 oberon_compare_signatures(oberon_context_t * ctx, oberon_type_t * a, oberon_type_t * b)
2170 {
2171 if(a -> num_decl != b -> num_decl)
2172 {
2173 oberon_error(ctx, "number parameters not matched");
2174 }
2175
2176 int num_param = a -> num_decl;
2177 oberon_object_t * param_a = a -> decl;
2178 oberon_object_t * param_b = b -> decl;
2179 for(int i = 0; i < num_param; i++)
2180 {
2181 if(strcmp(param_a -> name, param_b -> name) != 0)
2182 {
2183 oberon_error(ctx, "param %i name not matched", i + 1);
2184 }
2185
2186 if(param_a -> type != param_b -> type)
2187 {
2188 oberon_error(ctx, "param %i type not matched", i + 1);
2189 }
2190
2191 param_a = param_a -> next;
2192 param_b = param_b -> next;
2193 }
2194 }
2195
2196 static void
2197 oberon_make_return(oberon_context_t * ctx, oberon_expr_t * expr)
2198 {
2199 oberon_object_t * proc = ctx -> decl -> parent;
2200 oberon_type_t * result_type = proc -> type -> base;
2201
2202 if(result_type -> class == OBERON_TYPE_VOID)
2203 {
2204 if(expr != NULL)
2205 {
2206 oberon_error(ctx, "procedure has no result type");
2207 }
2208 }
2209 else
2210 {
2211 if(expr == NULL)
2212 {
2213 oberon_error(ctx, "procedure requires expression on result");
2214 }
2215
2216 expr = oberon_autocast_to(ctx, expr, result_type);
2217 }
2218
2219 proc -> has_return = 1;
2220
2221 oberon_generate_return(ctx, expr);
2222 }
2223
2224 static void
2225 oberon_proc_decl_body(oberon_context_t * ctx, oberon_object_t * proc)
2226 {
2227 oberon_assert_token(ctx, SEMICOLON);
2228
2229 ctx -> decl = proc -> scope;
2230
2231 oberon_decl_seq(ctx);
2232
2233 oberon_generate_begin_proc(ctx, proc);
2234
2235 if(ctx -> token == BEGIN)
2236 {
2237 oberon_assert_token(ctx, BEGIN);
2238 oberon_statement_seq(ctx);
2239 }
2240
2241 oberon_assert_token(ctx, END);
2242 char * name = oberon_assert_ident(ctx);
2243 if(strcmp(name, proc -> name) != 0)
2244 {
2245 oberon_error(ctx, "procedure name not matched");
2246 }
2247
2248 if(proc -> type -> base -> class == OBERON_TYPE_VOID
2249 && proc -> has_return == 0)
2250 {
2251 oberon_make_return(ctx, NULL);
2252 }
2253
2254 if(proc -> has_return == 0)
2255 {
2256 oberon_error(ctx, "procedure requires return");
2257 }
2258
2259 oberon_generate_end_proc(ctx);
2260 oberon_close_scope(ctx -> decl);
2261 }
2262
2263 static void
2264 oberon_proc_decl(oberon_context_t * ctx)
2265 {
2266 oberon_assert_token(ctx, PROCEDURE);
2267
2268 int forward = 0;
2269 if(ctx -> token == UPARROW)
2270 {
2271 oberon_assert_token(ctx, UPARROW);
2272 forward = 1;
2273 }
2274
2275 char * name;
2276 int export;
2277 int read_only;
2278 name = oberon_assert_ident(ctx);
2279 oberon_def(ctx, &export, &read_only);
2280
2281 oberon_scope_t * proc_scope;
2282 proc_scope = oberon_open_scope(ctx);
2283 ctx -> decl -> local = 1;
2284
2285 oberon_type_t * signature;
2286 signature = oberon_new_type_ptr(OBERON_TYPE_VOID);
2287 oberon_opt_formal_pars(ctx, &signature);
2288
2289 oberon_initialize_decl(ctx);
2290 oberon_generator_init_type(ctx, signature);
2291 oberon_close_scope(ctx -> decl);
2292
2293 oberon_object_t * proc;
2294 proc = oberon_find_object(ctx -> decl, name, 0);
2295 if(proc != NULL)
2296 {
2297 if(proc -> class != OBERON_CLASS_PROC)
2298 {
2299 oberon_error(ctx, "mult definition");
2300 }
2301
2302 if(forward == 0)
2303 {
2304 if(proc -> linked)
2305 {
2306 oberon_error(ctx, "mult procedure definition");
2307 }
2308 }
2309
2310 if(proc -> export != export || proc -> read_only != read_only)
2311 {
2312 oberon_error(ctx, "export type not matched");
2313 }
2314
2315 oberon_compare_signatures(ctx, proc -> type, signature);
2316 }
2317 else
2318 {
2319 proc = oberon_define_object(ctx -> decl, name, OBERON_CLASS_PROC, export, read_only, false);
2320 proc -> type = signature;
2321 proc -> scope = proc_scope;
2322 oberon_generator_init_proc(ctx, proc);
2323 }
2324
2325 proc -> scope -> parent = proc;
2326
2327 if(forward == 0)
2328 {
2329 proc -> linked = 1;
2330 oberon_proc_decl_body(ctx, proc);
2331 }
2332 }
2333
2334 static void
2335 oberon_const_decl(oberon_context_t * ctx)
2336 {
2337 oberon_item_t * value;
2338 oberon_object_t * constant;
2339
2340 constant = oberon_ident_def(ctx, OBERON_CLASS_CONST, false);
2341 oberon_assert_token(ctx, EQUAL);
2342 value = oberon_const_expr(ctx);
2343 constant -> value = value;
2344 }
2345
2346 static void
2347 oberon_make_array_type(oberon_context_t * ctx, oberon_expr_t * size, oberon_type_t * base, oberon_type_t ** type)
2348 {
2349 if(size -> is_item == 0)
2350 {
2351 oberon_error(ctx, "requires constant");
2352 }
2353
2354 if(size -> item.mode != MODE_INTEGER)
2355 {
2356 oberon_error(ctx, "requires integer constant");
2357 }
2358
2359 oberon_type_t * arr;
2360 arr = *type;
2361 arr -> class = OBERON_TYPE_ARRAY;
2362 arr -> size = size -> item.integer;
2363 arr -> base = base;
2364 }
2365
2366 static void
2367 oberon_qualident_type(oberon_context_t * ctx, oberon_type_t ** type)
2368 {
2369 char * name;
2370 oberon_object_t * to;
2371
2372 to = oberon_qualident(ctx, &name, 0);
2373
2374 //name = oberon_assert_ident(ctx);
2375 //to = oberon_find_object(ctx -> decl, name, 0);
2376
2377 if(to != NULL)
2378 {
2379 if(to -> class != OBERON_CLASS_TYPE)
2380 {
2381 oberon_error(ctx, "not a type");
2382 }
2383 }
2384 else
2385 {
2386 to = oberon_define_object(ctx -> decl, name, OBERON_CLASS_TYPE, false, false, false);
2387 to -> type = oberon_new_type_ptr(OBERON_TYPE_VOID);
2388 }
2389
2390 *type = to -> type;
2391 }
2392
2393 static void oberon_opt_formal_pars(oberon_context_t * ctx, oberon_type_t ** type);
2394
2395 /*
2396 * Правило граматики "type". Указатель type должен указывать на существующий объект!
2397 */
2398
2399 static void
2400 oberon_make_multiarray(oberon_context_t * ctx, oberon_expr_t * sizes, oberon_type_t * base, oberon_type_t ** type)
2401 {
2402 if(sizes == NULL)
2403 {
2404 *type = base;
2405 return;
2406 }
2407
2408 oberon_type_t * dim;
2409 dim = oberon_new_type_ptr(OBERON_TYPE_VOID);
2410
2411 oberon_make_multiarray(ctx, sizes -> next, base, &dim);
2412
2413 oberon_make_array_type(ctx, sizes, dim, type);
2414 }
2415
2416 static void
2417 oberon_make_open_array(oberon_context_t * ctx, oberon_type_t * base, oberon_type_t * type)
2418 {
2419 type -> class = OBERON_TYPE_ARRAY;
2420 type -> size = 0;
2421 type -> base = base;
2422 }
2423
2424 static void
2425 oberon_field_list(oberon_context_t * ctx, oberon_type_t * rec, oberon_scope_t * modscope)
2426 {
2427 if(ctx -> token == IDENT)
2428 {
2429 int num;
2430 oberon_object_t * list;
2431 oberon_type_t * type;
2432 type = oberon_new_type_ptr(OBERON_TYPE_VOID);
2433
2434 oberon_ident_list(ctx, OBERON_CLASS_FIELD, true, &num, &list);
2435 oberon_assert_token(ctx, COLON);
2436
2437 oberon_scope_t * current = ctx -> decl;
2438 ctx -> decl = modscope;
2439 oberon_type(ctx, &type);
2440 ctx -> decl = current;
2441
2442 oberon_object_t * field = list;
2443 for(int i = 0; i < num; i++)
2444 {
2445 field -> type = type;
2446 field = field -> next;
2447 }
2448
2449 rec -> num_decl += num;
2450 }
2451 }
2452
2453 static void
2454 oberon_type_record_body(oberon_context_t * ctx, oberon_type_t * rec)
2455 {
2456 oberon_scope_t * modscope = ctx -> mod -> decl;
2457 oberon_scope_t * oldscope = ctx -> decl;
2458 ctx -> decl = modscope;
2459
2460 if(ctx -> token == LPAREN)
2461 {
2462 oberon_assert_token(ctx, LPAREN);
2463
2464 oberon_object_t * typeobj;
2465 typeobj = oberon_qualident(ctx, NULL, true);
2466
2467 if(typeobj -> class != OBERON_CLASS_TYPE)
2468 {
2469 oberon_error(ctx, "base must be type");
2470 }
2471
2472 oberon_type_t * base = typeobj -> type;
2473 if(base -> class == OBERON_TYPE_POINTER)
2474 {
2475 base = base -> base;
2476 }
2477
2478 if(base -> class != OBERON_TYPE_RECORD)
2479 {
2480 oberon_error(ctx, "base must be record type");
2481 }
2482
2483 rec -> base = base;
2484 ctx -> decl = base -> scope;
2485
2486 oberon_assert_token(ctx, RPAREN);
2487 }
2488 else
2489 {
2490 ctx -> decl = NULL;
2491 }
2492
2493 oberon_scope_t * this_scope;
2494 this_scope = oberon_open_scope(ctx);
2495 this_scope -> local = true;
2496 this_scope -> parent = NULL;
2497 this_scope -> parent_type = rec;
2498
2499 oberon_field_list(ctx, rec, modscope);
2500 while(ctx -> token == SEMICOLON)
2501 {
2502 oberon_assert_token(ctx, SEMICOLON);
2503 oberon_field_list(ctx, rec, modscope);
2504 }
2505
2506 rec -> scope = this_scope;
2507 rec -> decl = this_scope -> list -> next;
2508 ctx -> decl = oldscope;
2509 }
2510
2511 static void
2512 oberon_type(oberon_context_t * ctx, oberon_type_t ** type)
2513 {
2514 if(ctx -> token == IDENT)
2515 {
2516 oberon_qualident_type(ctx, type);
2517 }
2518 else if(ctx -> token == ARRAY)
2519 {
2520 oberon_assert_token(ctx, ARRAY);
2521
2522 int num_sizes = 0;
2523 oberon_expr_t * sizes;
2524
2525 if(ISEXPR(ctx -> token))
2526 {
2527 oberon_expr_list(ctx, &num_sizes, &sizes, 1);
2528 }
2529
2530 oberon_assert_token(ctx, OF);
2531
2532 oberon_type_t * base;
2533 base = oberon_new_type_ptr(OBERON_TYPE_VOID);
2534 oberon_type(ctx, &base);
2535
2536 if(num_sizes == 0)
2537 {
2538 oberon_make_open_array(ctx, base, *type);
2539 }
2540 else
2541 {
2542 oberon_make_multiarray(ctx, sizes, base, type);
2543 }
2544 }
2545 else if(ctx -> token == RECORD)
2546 {
2547 oberon_type_t * rec;
2548 rec = *type;
2549 rec -> class = OBERON_TYPE_RECORD;
2550 rec -> module = ctx -> mod;
2551
2552 oberon_assert_token(ctx, RECORD);
2553 oberon_type_record_body(ctx, rec);
2554 oberon_assert_token(ctx, END);
2555
2556 *type = rec;
2557 }
2558 else if(ctx -> token == POINTER)
2559 {
2560 oberon_assert_token(ctx, POINTER);
2561 oberon_assert_token(ctx, TO);
2562
2563 oberon_type_t * base;
2564 base = oberon_new_type_ptr(OBERON_TYPE_VOID);
2565 oberon_type(ctx, &base);
2566
2567 oberon_type_t * ptr;
2568 ptr = *type;
2569 ptr -> class = OBERON_TYPE_POINTER;
2570 ptr -> base = base;
2571 }
2572 else if(ctx -> token == PROCEDURE)
2573 {
2574 oberon_open_scope(ctx);
2575 oberon_assert_token(ctx, PROCEDURE);
2576 oberon_opt_formal_pars(ctx, type);
2577 oberon_close_scope(ctx -> decl);
2578 }
2579 else
2580 {
2581 oberon_error(ctx, "invalid type declaration");
2582 }
2583 }
2584
2585 static void
2586 oberon_type_decl(oberon_context_t * ctx)
2587 {
2588 char * name;
2589 oberon_object_t * newtype;
2590 oberon_type_t * type;
2591 int export;
2592 int read_only;
2593
2594 name = oberon_assert_ident(ctx);
2595 oberon_def(ctx, &export, &read_only);
2596
2597 newtype = oberon_find_object(ctx -> decl, name, 0);
2598 if(newtype == NULL)
2599 {
2600 newtype = oberon_define_object(ctx -> decl, name, OBERON_CLASS_TYPE, export, read_only, false);
2601 newtype -> type = oberon_new_type_ptr(OBERON_TYPE_VOID);
2602 assert(newtype -> type);
2603 }
2604 else
2605 {
2606 if(newtype -> class != OBERON_CLASS_TYPE)
2607 {
2608 oberon_error(ctx, "mult definition");
2609 }
2610
2611 if(newtype -> linked)
2612 {
2613 oberon_error(ctx, "mult definition - already linked");
2614 }
2615
2616 newtype -> export = export;
2617 newtype -> read_only = read_only;
2618 }
2619
2620 oberon_assert_token(ctx, EQUAL);
2621
2622 type = newtype -> type;
2623 oberon_type(ctx, &type);
2624
2625 if(type -> class == OBERON_TYPE_VOID)
2626 {
2627 oberon_error(ctx, "recursive alias declaration");
2628 }
2629
2630 newtype -> type = type;
2631 newtype -> linked = 1;
2632 }
2633
2634 static void oberon_prevent_recursive_object(oberon_context_t * ctx, oberon_object_t * x);
2635 static void oberon_prevent_recursive_type(oberon_context_t * ctx, oberon_type_t * type);
2636
2637 static void
2638 oberon_prevent_recursive_pointer(oberon_context_t * ctx, oberon_type_t * type)
2639 {
2640 if(type -> class != OBERON_TYPE_POINTER
2641 && type -> class != OBERON_TYPE_ARRAY)
2642 {
2643 return;
2644 }
2645
2646 if(type -> recursive)
2647 {
2648 oberon_error(ctx, "recursive pointer declaration");
2649 }
2650
2651 if(type -> class == OBERON_TYPE_POINTER
2652 && type -> base -> class == OBERON_TYPE_POINTER)
2653 {
2654 oberon_error(ctx, "attempt to make pointer to pointer");
2655 }
2656
2657 type -> recursive = 1;
2658
2659 oberon_prevent_recursive_pointer(ctx, type -> base);
2660
2661 type -> recursive = 0;
2662 }
2663
2664 static void
2665 oberon_prevent_recursive_record(oberon_context_t * ctx, oberon_type_t * type)
2666 {
2667 if(type -> class != OBERON_TYPE_RECORD)
2668 {
2669 return;
2670 }
2671
2672 if(type -> recursive)
2673 {
2674 oberon_error(ctx, "recursive record declaration");
2675 }
2676
2677 type -> recursive = 1;
2678
2679 int num_fields = type -> num_decl;
2680 oberon_object_t * field = type -> decl;
2681 for(int i = 0; i < num_fields; i++)
2682 {
2683 oberon_prevent_recursive_object(ctx, field);
2684 field = field -> next;
2685 }
2686
2687 type -> recursive = 0;
2688 }
2689 static void
2690 oberon_prevent_recursive_procedure(oberon_context_t * ctx, oberon_type_t * type)
2691 {
2692 if(type -> class != OBERON_TYPE_PROCEDURE)
2693 {
2694 return;
2695 }
2696
2697 if(type -> recursive)
2698 {
2699 oberon_error(ctx, "recursive procedure declaration");
2700 }
2701
2702 type -> recursive = 1;
2703
2704 int num_fields = type -> num_decl;
2705 oberon_object_t * field = type -> decl;
2706 for(int i = 0; i < num_fields; i++)
2707 {
2708 oberon_prevent_recursive_object(ctx, field);
2709 field = field -> next;
2710 }
2711
2712 type -> recursive = 0;
2713 }
2714
2715 static void
2716 oberon_prevent_recursive_array(oberon_context_t * ctx, oberon_type_t * type)
2717 {
2718 if(type -> class != OBERON_TYPE_ARRAY)
2719 {
2720 return;
2721 }
2722
2723 if(type -> recursive)
2724 {
2725 oberon_error(ctx, "recursive array declaration");
2726 }
2727
2728 type -> recursive = 1;
2729
2730 oberon_prevent_recursive_type(ctx, type -> base);
2731
2732 type -> recursive = 0;
2733 }
2734
2735 static void
2736 oberon_prevent_recursive_type(oberon_context_t * ctx, oberon_type_t * type)
2737 {
2738 if(type -> class == OBERON_TYPE_POINTER)
2739 {
2740 oberon_prevent_recursive_pointer(ctx, type);
2741 }
2742 else if(type -> class == OBERON_TYPE_RECORD)
2743 {
2744 oberon_prevent_recursive_record(ctx, type);
2745 }
2746 else if(type -> class == OBERON_TYPE_ARRAY)
2747 {
2748 oberon_prevent_recursive_array(ctx, type);
2749 }
2750 else if(type -> class == OBERON_TYPE_PROCEDURE)
2751 {
2752 oberon_prevent_recursive_procedure(ctx, type);
2753 }
2754 }
2755
2756 static void
2757 oberon_prevent_recursive_object(oberon_context_t * ctx, oberon_object_t * x)
2758 {
2759 switch(x -> class)
2760 {
2761 case OBERON_CLASS_VAR:
2762 case OBERON_CLASS_TYPE:
2763 case OBERON_CLASS_PARAM:
2764 case OBERON_CLASS_VAR_PARAM:
2765 case OBERON_CLASS_FIELD:
2766 oberon_prevent_recursive_type(ctx, x -> type);
2767 break;
2768 case OBERON_CLASS_CONST:
2769 case OBERON_CLASS_PROC:
2770 case OBERON_CLASS_MODULE:
2771 break;
2772 default:
2773 oberon_error(ctx, "oberon_prevent_recursive_object: wat");
2774 break;
2775 }
2776 }
2777
2778 static void
2779 oberon_prevent_recursive_decl(oberon_context_t * ctx)
2780 {
2781 oberon_object_t * x = ctx -> decl -> list -> next;
2782
2783 while(x)
2784 {
2785 oberon_prevent_recursive_object(ctx, x);
2786 x = x -> next;
2787 }
2788 }
2789
2790 static void oberon_initialize_object(oberon_context_t * ctx, oberon_object_t * x);
2791 static void oberon_initialize_type(oberon_context_t * ctx, oberon_type_t * type);
2792
2793 static void
2794 oberon_initialize_record_fields(oberon_context_t * ctx, oberon_type_t * type)
2795 {
2796 if(type -> class != OBERON_TYPE_RECORD)
2797 {
2798 return;
2799 }
2800
2801 int num_fields = type -> num_decl;
2802 oberon_object_t * field = type -> decl;
2803 for(int i = 0; i < num_fields; i++)
2804 {
2805 if(field -> type -> class == OBERON_TYPE_POINTER)
2806 {
2807 oberon_initialize_type(ctx, field -> type);
2808 }
2809
2810 oberon_initialize_object(ctx, field);
2811 field = field -> next;
2812 }
2813
2814 oberon_generator_init_record(ctx, type);
2815 }
2816
2817 static void
2818 oberon_initialize_type(oberon_context_t * ctx, oberon_type_t * type)
2819 {
2820 if(type -> class == OBERON_TYPE_VOID)
2821 {
2822 oberon_error(ctx, "undeclarated type");
2823 }
2824
2825 if(type -> initialized)
2826 {
2827 return;
2828 }
2829
2830 type -> initialized = 1;
2831
2832 if(type -> class == OBERON_TYPE_POINTER)
2833 {
2834 oberon_initialize_type(ctx, type -> base);
2835 oberon_generator_init_type(ctx, type);
2836 }
2837 else if(type -> class == OBERON_TYPE_ARRAY)
2838 {
2839 if(type -> size != 0)
2840 {
2841 if(type -> base -> class == OBERON_TYPE_ARRAY)
2842 {
2843 if(type -> base -> size == 0)
2844 {
2845 oberon_error(ctx, "open array not allowed as array element");
2846 }
2847 }
2848 }
2849
2850 oberon_initialize_type(ctx, type -> base);
2851 oberon_generator_init_type(ctx, type);
2852 }
2853 else if(type -> class == OBERON_TYPE_RECORD)
2854 {
2855 oberon_generator_init_type(ctx, type);
2856 oberon_initialize_record_fields(ctx, type);
2857 }
2858 else if(type -> class == OBERON_TYPE_PROCEDURE)
2859 {
2860 int num_fields = type -> num_decl;
2861 oberon_object_t * field = type -> decl;
2862 for(int i = 0; i < num_fields; i++)
2863 {
2864 oberon_initialize_object(ctx, field);
2865 field = field -> next;
2866 }
2867
2868 oberon_generator_init_type(ctx, type);
2869 }
2870 else
2871 {
2872 oberon_generator_init_type(ctx, type);
2873 }
2874 }
2875
2876 static void
2877 oberon_initialize_object(oberon_context_t * ctx, oberon_object_t * x)
2878 {
2879 if(x -> initialized)
2880 {
2881 return;
2882 }
2883
2884 x -> initialized = 1;
2885
2886 switch(x -> class)
2887 {
2888 case OBERON_CLASS_TYPE:
2889 oberon_initialize_type(ctx, x -> type);
2890 break;
2891 case OBERON_CLASS_VAR:
2892 case OBERON_CLASS_FIELD:
2893 if(x -> type -> class == OBERON_TYPE_ARRAY)
2894 {
2895 if(x -> type -> size == 0)
2896 {
2897 oberon_error(ctx, "open array not allowed as variable or field");
2898 }
2899 }
2900 oberon_initialize_type(ctx, x -> type);
2901 oberon_generator_init_var(ctx, x);
2902 break;
2903 case OBERON_CLASS_PARAM:
2904 case OBERON_CLASS_VAR_PARAM:
2905 oberon_initialize_type(ctx, x -> type);
2906 oberon_generator_init_var(ctx, x);
2907 break;
2908 case OBERON_CLASS_CONST:
2909 case OBERON_CLASS_PROC:
2910 case OBERON_CLASS_MODULE:
2911 break;
2912 default:
2913 oberon_error(ctx, "oberon_initialize_object: wat");
2914 break;
2915 }
2916 }
2917
2918 static void
2919 oberon_initialize_decl(oberon_context_t * ctx)
2920 {
2921 oberon_object_t * x = ctx -> decl -> list;
2922
2923 while(x -> next)
2924 {
2925 oberon_initialize_object(ctx, x -> next);
2926 x = x -> next;
2927 }
2928 }
2929
2930 static void
2931 oberon_prevent_undeclarated_procedures(oberon_context_t * ctx)
2932 {
2933 oberon_object_t * x = ctx -> decl -> list;
2934
2935 while(x -> next)
2936 {
2937 if(x -> next -> class == OBERON_CLASS_PROC)
2938 {
2939 if(x -> next -> linked == 0)
2940 {
2941 oberon_error(ctx, "unresolved forward declaration");
2942 }
2943 }
2944 x = x -> next;
2945 }
2946 }
2947
2948 static void
2949 oberon_decl_seq(oberon_context_t * ctx)
2950 {
2951 if(ctx -> token == CONST)
2952 {
2953 oberon_assert_token(ctx, CONST);
2954 while(ctx -> token == IDENT)
2955 {
2956 oberon_const_decl(ctx);
2957 oberon_assert_token(ctx, SEMICOLON);
2958 }
2959 }
2960
2961 if(ctx -> token == TYPE)
2962 {
2963 oberon_assert_token(ctx, TYPE);
2964 while(ctx -> token == IDENT)
2965 {
2966 oberon_type_decl(ctx);
2967 oberon_assert_token(ctx, SEMICOLON);
2968 }
2969 }
2970
2971 if(ctx -> token == VAR)
2972 {
2973 oberon_assert_token(ctx, VAR);
2974 while(ctx -> token == IDENT)
2975 {
2976 oberon_var_decl(ctx);
2977 oberon_assert_token(ctx, SEMICOLON);
2978 }
2979 }
2980
2981 oberon_prevent_recursive_decl(ctx);
2982 oberon_initialize_decl(ctx);
2983
2984 while(ctx -> token == PROCEDURE)
2985 {
2986 oberon_proc_decl(ctx);
2987 oberon_assert_token(ctx, SEMICOLON);
2988 }
2989
2990 oberon_prevent_undeclarated_procedures(ctx);
2991 }
2992
2993 static oberon_expr_t *
2994 oberon_make_temp_var_item(oberon_context_t * ctx, oberon_type_t * type)
2995 {
2996 oberon_object_t * x;
2997 oberon_expr_t * expr;
2998
2999 x = oberon_create_object(ctx -> decl, "TEMP", OBERON_CLASS_VAR, false, false);
3000 x -> local = true;
3001 x -> type = type;
3002 oberon_generator_init_temp_var(ctx, x);
3003
3004 expr = oberon_new_item(MODE_VAR, type, false);
3005 expr -> item.var = x;
3006 return expr;
3007 }
3008
3009 static void
3010 oberon_statement_seq(oberon_context_t * ctx);
3011
3012 static void
3013 oberon_assign(oberon_context_t * ctx, oberon_expr_t * src, oberon_expr_t * dst)
3014 {
3015 if(dst -> read_only)
3016 {
3017 oberon_error(ctx, "read-only destination");
3018 }
3019
3020 oberon_check_dst(ctx, dst);
3021 src = oberon_autocast_to(ctx, src, dst -> result);
3022 oberon_generate_assign(ctx, src, dst);
3023 }
3024
3025 static void
3026 oberon_statement(oberon_context_t * ctx)
3027 {
3028 oberon_expr_t * item1;
3029 oberon_expr_t * item2;
3030
3031 if(ctx -> token == IDENT)
3032 {
3033 item1 = oberon_designator(ctx);
3034 if(ctx -> token == ASSIGN)
3035 {
3036 oberon_assert_token(ctx, ASSIGN);
3037 item2 = oberon_expr(ctx);
3038 oberon_assign(ctx, item2, item1);
3039 }
3040 else
3041 {
3042 oberon_opt_proc_parens(ctx, item1);
3043 }
3044 }
3045 else if(ctx -> token == IF)
3046 {
3047 gen_label_t * end;
3048 gen_label_t * els;
3049 oberon_expr_t * cond;
3050
3051 els = oberon_generator_reserve_label(ctx);
3052 end = oberon_generator_reserve_label(ctx);
3053
3054 oberon_assert_token(ctx, IF);
3055 cond = oberon_expr(ctx);
3056 if(cond -> result -> class != OBERON_TYPE_BOOLEAN)
3057 {
3058 oberon_error(ctx, "condition must be boolean");
3059 }
3060 oberon_assert_token(ctx, THEN);
3061 oberon_generate_branch(ctx, cond, false, els);
3062 oberon_statement_seq(ctx);
3063 oberon_generate_goto(ctx, end);
3064 oberon_generate_label(ctx, els);
3065
3066 while(ctx -> token == ELSIF)
3067 {
3068 els = oberon_generator_reserve_label(ctx);
3069
3070 oberon_assert_token(ctx, ELSIF);
3071 cond = oberon_expr(ctx);
3072 if(cond -> result -> class != OBERON_TYPE_BOOLEAN)
3073 {
3074 oberon_error(ctx, "condition must be boolean");
3075 }
3076 oberon_assert_token(ctx, THEN);
3077 oberon_generate_branch(ctx, cond, false, els);
3078 oberon_statement_seq(ctx);
3079 oberon_generate_goto(ctx, end);
3080 oberon_generate_label(ctx, els);
3081 }
3082
3083 if(ctx -> token == ELSE)
3084 {
3085 oberon_assert_token(ctx, ELSE);
3086 oberon_statement_seq(ctx);
3087 }
3088
3089 oberon_generate_label(ctx, end);
3090 oberon_assert_token(ctx, END);
3091 }
3092 else if(ctx -> token == WHILE)
3093 {
3094 gen_label_t * begin;
3095 gen_label_t * end;
3096 oberon_expr_t * cond;
3097
3098 begin = oberon_generator_reserve_label(ctx);
3099 end = oberon_generator_reserve_label(ctx);
3100
3101 oberon_assert_token(ctx, WHILE);
3102 oberon_generate_label(ctx, begin);
3103 cond = oberon_expr(ctx);
3104 if(cond -> result -> class != OBERON_TYPE_BOOLEAN)
3105 {
3106 oberon_error(ctx, "condition must be boolean");
3107 }
3108 oberon_generate_branch(ctx, cond, false, end);
3109
3110 oberon_assert_token(ctx, DO);
3111 oberon_statement_seq(ctx);
3112 oberon_generate_goto(ctx, begin);
3113
3114 oberon_assert_token(ctx, END);
3115 oberon_generate_label(ctx, end);
3116 }
3117 else if(ctx -> token == REPEAT)
3118 {
3119 gen_label_t * begin;
3120 oberon_expr_t * cond;
3121
3122 begin = oberon_generator_reserve_label(ctx);
3123 oberon_generate_label(ctx, begin);
3124 oberon_assert_token(ctx, REPEAT);
3125
3126 oberon_statement_seq(ctx);
3127
3128 oberon_assert_token(ctx, UNTIL);
3129
3130 cond = oberon_expr(ctx);
3131 if(cond -> result -> class != OBERON_TYPE_BOOLEAN)
3132 {
3133 oberon_error(ctx, "condition must be boolean");
3134 }
3135
3136 oberon_generate_branch(ctx, cond, true, begin);
3137 }
3138 else if(ctx -> token == FOR)
3139 {
3140 oberon_expr_t * from;
3141 oberon_expr_t * index;
3142 oberon_expr_t * to;
3143 oberon_expr_t * bound;
3144 oberon_expr_t * by;
3145 oberon_expr_t * cond;
3146 oberon_expr_t * count;
3147 gen_label_t * begin;
3148 gen_label_t * end;
3149 char * iname;
3150 int op;
3151
3152 begin = oberon_generator_reserve_label(ctx);
3153 end = oberon_generator_reserve_label(ctx);
3154
3155 oberon_assert_token(ctx, FOR);
3156 iname = oberon_assert_ident(ctx);
3157 index = oberon_ident_item(ctx, iname);
3158 oberon_assert_token(ctx, ASSIGN);
3159 from = oberon_expr(ctx);
3160 oberon_assign(ctx, from, index);
3161 oberon_assert_token(ctx, TO);
3162 bound = oberon_make_temp_var_item(ctx, index -> result);
3163 to = oberon_expr(ctx);
3164 oberon_assign(ctx, to, bound);
3165 if(ctx -> token == BY)
3166 {
3167 oberon_assert_token(ctx, BY);
3168 by = (oberon_expr_t *) oberon_const_expr(ctx);
3169 }
3170 else
3171 {
3172 by = oberon_integer_item(ctx, 1);
3173 }
3174
3175 if(by -> result -> class != OBERON_TYPE_INTEGER)
3176 {
3177 oberon_error(ctx, "must be integer");
3178 }
3179
3180 if(by -> item.integer > 0)
3181 {
3182 op = LEQ;
3183 }
3184 else if(by -> item.integer < 0)
3185 {
3186 op = GEQ;
3187 }
3188 else
3189 {
3190 oberon_error(ctx, "zero step not allowed");
3191 }
3192
3193 oberon_assert_token(ctx, DO);
3194 oberon_generate_label(ctx, begin);
3195 cond = oberon_make_bin_op(ctx, op, index, bound);
3196 oberon_generate_branch(ctx, cond, false, end);
3197 oberon_statement_seq(ctx);
3198 count = oberon_make_bin_op(ctx, PLUS, index, by);
3199 oberon_assign(ctx, count, index);
3200 oberon_generate_goto(ctx, begin);
3201 oberon_generate_label(ctx, end);
3202 oberon_assert_token(ctx, END);
3203 }
3204 else if(ctx -> token == LOOP)
3205 {
3206 gen_label_t * begin;
3207 gen_label_t * end;
3208
3209 begin = oberon_generator_reserve_label(ctx);
3210 end = oberon_generator_reserve_label(ctx);
3211
3212 oberon_open_scope(ctx);
3213 oberon_assert_token(ctx, LOOP);
3214 oberon_generate_label(ctx, begin);
3215 ctx -> decl -> exit_label = end;
3216 oberon_statement_seq(ctx);
3217 oberon_generate_goto(ctx, begin);
3218 oberon_generate_label(ctx, end);
3219 oberon_assert_token(ctx, END);
3220 oberon_close_scope(ctx -> decl);
3221 }
3222 else if(ctx -> token == EXIT)
3223 {
3224 oberon_assert_token(ctx, EXIT);
3225 if(ctx -> decl -> exit_label == NULL)
3226 {
3227 oberon_error(ctx, "not in LOOP-END");
3228 }
3229 oberon_generate_goto(ctx, ctx -> decl -> exit_label);
3230 }
3231 else if(ctx -> token == RETURN)
3232 {
3233 oberon_assert_token(ctx, RETURN);
3234 if(ISEXPR(ctx -> token))
3235 {
3236 oberon_expr_t * expr;
3237 expr = oberon_expr(ctx);
3238 oberon_make_return(ctx, expr);
3239 }
3240 else
3241 {
3242 oberon_make_return(ctx, NULL);
3243 }
3244 }
3245 }
3246
3247 static void
3248 oberon_statement_seq(oberon_context_t * ctx)
3249 {
3250 oberon_statement(ctx);
3251 while(ctx -> token == SEMICOLON)
3252 {
3253 oberon_assert_token(ctx, SEMICOLON);
3254 oberon_statement(ctx);
3255 }
3256 }
3257
3258 static void
3259 oberon_import_module(oberon_context_t * ctx, char * alias, char * name)
3260 {
3261 oberon_module_t * m = ctx -> module_list;
3262 while(m && strcmp(m -> name, name) != 0)
3263 {
3264 m = m -> next;
3265 }
3266
3267 if(m == NULL)
3268 {
3269 const char * code;
3270 code = ctx -> import_module(name);
3271 if(code == NULL)
3272 {
3273 oberon_error(ctx, "no such module");
3274 }
3275
3276 m = oberon_compile_module(ctx, code);
3277 assert(m);
3278 }
3279
3280 if(m -> ready == 0)
3281 {
3282 oberon_error(ctx, "cyclic module import");
3283 }
3284
3285 oberon_object_t * ident;
3286 ident = oberon_define_object(ctx -> decl, alias, OBERON_CLASS_MODULE, false, false, false);
3287 ident -> module = m;
3288 }
3289
3290 static void
3291 oberon_import_decl(oberon_context_t * ctx)
3292 {
3293 char * alias;
3294 char * name;
3295
3296 alias = name = oberon_assert_ident(ctx);
3297 if(ctx -> token == ASSIGN)
3298 {
3299 oberon_assert_token(ctx, ASSIGN);
3300 name = oberon_assert_ident(ctx);
3301 }
3302
3303 oberon_import_module(ctx, alias, name);
3304 }
3305
3306 static void
3307 oberon_import_list(oberon_context_t * ctx)
3308 {
3309 oberon_assert_token(ctx, IMPORT);
3310
3311 oberon_import_decl(ctx);
3312 while(ctx -> token == COMMA)
3313 {
3314 oberon_assert_token(ctx, COMMA);
3315 oberon_import_decl(ctx);
3316 }
3317
3318 oberon_assert_token(ctx, SEMICOLON);
3319 }
3320
3321 static void
3322 oberon_parse_module(oberon_context_t * ctx)
3323 {
3324 char * name1;
3325 char * name2;
3326 oberon_read_token(ctx);
3327
3328 oberon_assert_token(ctx, MODULE);
3329 name1 = oberon_assert_ident(ctx);
3330 oberon_assert_token(ctx, SEMICOLON);
3331 ctx -> mod -> name = name1;
3332
3333 oberon_generator_init_module(ctx, ctx -> mod);
3334
3335 if(ctx -> token == IMPORT)
3336 {
3337 oberon_import_list(ctx);
3338 }
3339
3340 oberon_decl_seq(ctx);
3341
3342 oberon_generate_begin_module(ctx);
3343 if(ctx -> token == BEGIN)
3344 {
3345 oberon_assert_token(ctx, BEGIN);
3346 oberon_statement_seq(ctx);
3347 }
3348 oberon_generate_end_module(ctx);
3349
3350 oberon_assert_token(ctx, END);
3351 name2 = oberon_assert_ident(ctx);
3352 oberon_assert_token(ctx, DOT);
3353
3354 if(strcmp(name1, name2) != 0)
3355 {
3356 oberon_error(ctx, "module name not matched");
3357 }
3358
3359 oberon_generator_fini_module(ctx -> mod);
3360 }
3361
3362 // =======================================================================
3363 // LIBRARY
3364 // =======================================================================
3365
3366 static void
3367 register_default_types(oberon_context_t * ctx)
3368 {
3369 ctx -> void_type = oberon_new_type_ptr(OBERON_TYPE_VOID);
3370 oberon_generator_init_type(ctx, ctx -> void_type);
3371
3372 ctx -> void_ptr_type = oberon_new_type_ptr(OBERON_TYPE_POINTER);
3373 ctx -> void_ptr_type -> base = ctx -> void_type;
3374 oberon_generator_init_type(ctx, ctx -> void_ptr_type);
3375
3376 ctx -> string_type = oberon_new_type_string(1);
3377 oberon_generator_init_type(ctx, ctx -> string_type);
3378
3379 ctx -> bool_type = oberon_new_type_boolean();
3380 oberon_define_type(ctx -> world_scope, "BOOLEAN", ctx -> bool_type, 1);
3381
3382 ctx -> byte_type = oberon_new_type_integer(1);
3383 oberon_define_type(ctx -> world_scope, "BYTE", ctx -> byte_type, 1);
3384
3385 ctx -> shortint_type = oberon_new_type_integer(2);
3386 oberon_define_type(ctx -> world_scope, "SHORTINT", ctx -> shortint_type, 1);
3387
3388 ctx -> int_type = oberon_new_type_integer(4);
3389 oberon_define_type(ctx -> world_scope, "INTEGER", ctx -> int_type, 1);
3390
3391 ctx -> longint_type = oberon_new_type_integer(8);
3392 oberon_define_type(ctx -> world_scope, "LONGINT", ctx -> longint_type, 1);
3393
3394 ctx -> real_type = oberon_new_type_real(4);
3395 oberon_define_type(ctx -> world_scope, "REAL", ctx -> real_type, 1);
3396
3397 ctx -> longreal_type = oberon_new_type_real(8);
3398 oberon_define_type(ctx -> world_scope, "LONGREAL", ctx -> longreal_type, 1);
3399
3400 ctx -> char_type = oberon_new_type_char(1);
3401 oberon_define_type(ctx -> world_scope, "CHAR", ctx -> char_type, 1);
3402 }
3403
3404 static void
3405 oberon_new_intrinsic(oberon_context_t * ctx, char * name, GenerateFuncCallback f, GenerateProcCallback p)
3406 {
3407 oberon_object_t * proc;
3408 proc = oberon_define_object(ctx -> decl, name, OBERON_CLASS_PROC, true, false, false);
3409 proc -> type = oberon_new_type_ptr(OBERON_TYPE_PROCEDURE);
3410 proc -> type -> sysproc = true;
3411 proc -> type -> genfunc = f;
3412 proc -> type -> genproc = p;
3413 }
3414
3415 static oberon_expr_t *
3416 oberon_make_min_call(oberon_context_t * ctx, int num_args, oberon_expr_t * list_args)
3417 {
3418 if(num_args < 1)
3419 {
3420 oberon_error(ctx, "too few arguments");
3421 }
3422
3423 if(num_args > 1)
3424 {
3425 oberon_error(ctx, "too mach arguments");
3426 }
3427
3428 oberon_expr_t * arg;
3429 arg = list_args;
3430
3431 if(!arg -> is_item || arg -> item.mode != MODE_TYPE)
3432 {
3433 oberon_error(ctx, "MIN accept only type");
3434 }
3435
3436 oberon_expr_t * expr;
3437 int bits = arg -> result -> size * 8;
3438 switch(arg -> result -> class)
3439 {
3440 case OBERON_TYPE_INTEGER:
3441 expr = oberon_integer_item(ctx, -powl(2, bits - 1));
3442 break;
3443 default:
3444 oberon_error(ctx, "allowed only basic types");
3445 break;
3446 }
3447
3448 return expr;
3449 }
3450
3451 static oberon_expr_t *
3452 oberon_make_max_call(oberon_context_t * ctx, int num_args, oberon_expr_t * list_args)
3453 {
3454 if(num_args < 1)
3455 {
3456 oberon_error(ctx, "too few arguments");
3457 }
3458
3459 if(num_args > 1)
3460 {
3461 oberon_error(ctx, "too mach arguments");
3462 }
3463
3464 oberon_expr_t * arg;
3465 arg = list_args;
3466
3467 if(!arg -> is_item || arg -> item.mode != MODE_TYPE)
3468 {
3469 oberon_error(ctx, "MAX accept only type");
3470 }
3471
3472 oberon_expr_t * expr;
3473 int bits = arg -> result -> size * 8;
3474 switch(arg -> result -> class)
3475 {
3476 case OBERON_TYPE_INTEGER:
3477 expr = oberon_integer_item(ctx, powl(2, bits - 1) - 1);
3478 break;
3479 default:
3480 oberon_error(ctx, "allowed only basic types");
3481 break;
3482 }
3483
3484 return expr;
3485 }
3486
3487 static oberon_expr_t *
3488 oberon_make_size_call(oberon_context_t * ctx, int num_args, oberon_expr_t * list_args)
3489 {
3490 if(num_args < 1)
3491 {
3492 oberon_error(ctx, "too few arguments");
3493 }
3494
3495 if(num_args > 1)
3496 {
3497 oberon_error(ctx, "too mach arguments");
3498 }
3499
3500 oberon_expr_t * arg;
3501 arg = list_args;
3502
3503 if(!arg -> is_item || arg -> item.mode != MODE_TYPE)
3504 {
3505 oberon_error(ctx, "SIZE accept only type");
3506 }
3507
3508 int size;
3509 oberon_expr_t * expr;
3510 oberon_type_t * type = arg -> result;
3511 switch(type -> class)
3512 {
3513 case OBERON_TYPE_INTEGER:
3514 case OBERON_TYPE_BOOLEAN:
3515 case OBERON_TYPE_REAL:
3516 size = type -> size;
3517 break;
3518 default:
3519 oberon_error(ctx, "TODO SIZE");
3520 break;
3521 }
3522
3523 expr = oberon_integer_item(ctx, size);
3524 return expr;
3525 }
3526
3527 static oberon_expr_t *
3528 oberon_make_abs_call(oberon_context_t * ctx, int num_args, oberon_expr_t * list_args)
3529 {
3530 if(num_args < 1)
3531 {
3532 oberon_error(ctx, "too few arguments");
3533 }
3534
3535 if(num_args > 1)
3536 {
3537 oberon_error(ctx, "too mach arguments");
3538 }
3539
3540 oberon_expr_t * arg;
3541 arg = list_args;
3542 oberon_check_src(ctx, arg);
3543
3544 oberon_type_t * result_type;
3545 result_type = arg -> result;
3546
3547 if(result_type -> class != OBERON_TYPE_INTEGER)
3548 {
3549 oberon_error(ctx, "ABS accepts only integers");
3550 }
3551
3552 oberon_expr_t * expr;
3553 expr = oberon_new_operator(OP_ABS, result_type, arg, NULL);
3554 return expr;
3555 }
3556
3557 static void
3558 oberon_make_new_call(oberon_context_t * ctx, int num_args, oberon_expr_t * list_args)
3559 {
3560 if(num_args < 1)
3561 {
3562 oberon_error(ctx, "too few arguments");
3563 }
3564
3565
3566 oberon_expr_t * dst;
3567 dst = list_args;
3568 oberon_check_dst(ctx, dst);
3569
3570 oberon_type_t * type;
3571 type = dst -> result;
3572
3573 if(type -> class != OBERON_TYPE_POINTER)
3574 {
3575 oberon_error(ctx, "not a pointer");
3576 }
3577
3578 type = type -> base;
3579
3580 oberon_expr_t * src;
3581 src = oberon_new_item(MODE_NEW, dst -> result, 0);
3582 src -> item.num_args = 0;
3583 src -> item.args = NULL;
3584
3585 int max_args = 1;
3586 if(type -> class == OBERON_TYPE_ARRAY)
3587 {
3588 if(type -> size == 0)
3589 {
3590 oberon_type_t * x = type;
3591 while(x -> class == OBERON_TYPE_ARRAY)
3592 {
3593 if(x -> size == 0)
3594 {
3595 max_args += 1;
3596 }
3597 x = x -> base;
3598 }
3599 }
3600
3601 if(num_args < max_args)
3602 {
3603 oberon_error(ctx, "too few arguments");
3604 }
3605
3606 if(num_args > max_args)
3607 {
3608 oberon_error(ctx, "too mach arguments");
3609 }
3610
3611 int num_sizes = max_args - 1;
3612 oberon_expr_t * size_list = list_args -> next;
3613
3614 oberon_expr_t * arg = size_list;
3615 for(int i = 0; i < max_args - 1; i++)
3616 {
3617 oberon_check_src(ctx, arg);
3618 if(arg -> result -> class != OBERON_TYPE_INTEGER)
3619 {
3620 oberon_error(ctx, "size must be integer");
3621 }
3622 arg = arg -> next;
3623 }
3624
3625 src -> item.num_args = num_sizes;
3626 src -> item.args = size_list;
3627 }
3628 else if(type -> class != OBERON_TYPE_RECORD)
3629 {
3630 oberon_error(ctx, "oberon_make_new_call: wat");
3631 }
3632
3633 if(num_args > max_args)
3634 {
3635 oberon_error(ctx, "too mach arguments");
3636 }
3637
3638 oberon_assign(ctx, src, dst);
3639 }
3640
3641 oberon_context_t *
3642 oberon_create_context(ModuleImportCallback import_module)
3643 {
3644 oberon_context_t * ctx = calloc(1, sizeof *ctx);
3645
3646 oberon_scope_t * world_scope;
3647 world_scope = oberon_open_scope(ctx);
3648 ctx -> world_scope = world_scope;
3649
3650 ctx -> import_module = import_module;
3651
3652 oberon_generator_init_context(ctx);
3653
3654 register_default_types(ctx);
3655
3656 /* Functions */
3657 oberon_new_intrinsic(ctx, "ABS", oberon_make_abs_call, NULL);
3658 oberon_new_intrinsic(ctx, "MIN", oberon_make_min_call, NULL);
3659 oberon_new_intrinsic(ctx, "MAX", oberon_make_max_call, NULL);
3660 oberon_new_intrinsic(ctx, "SIZE", oberon_make_size_call, NULL);
3661
3662 /* Procedures */
3663 oberon_new_intrinsic(ctx, "NEW", NULL, oberon_make_new_call);
3664
3665 return ctx;
3666 }
3667
3668 void
3669 oberon_destroy_context(oberon_context_t * ctx)
3670 {
3671 oberon_generator_destroy_context(ctx);
3672 free(ctx);
3673 }
3674
3675 oberon_module_t *
3676 oberon_compile_module(oberon_context_t * ctx, const char * newcode)
3677 {
3678 const char * code = ctx -> code;
3679 int code_index = ctx -> code_index;
3680 char c = ctx -> c;
3681 int token = ctx -> token;
3682 char * string = ctx -> string;
3683 int integer = ctx -> integer;
3684 int real = ctx -> real;
3685 bool longmode = ctx -> longmode;
3686 oberon_scope_t * decl = ctx -> decl;
3687 oberon_module_t * mod = ctx -> mod;
3688
3689 oberon_scope_t * module_scope;
3690 module_scope = oberon_open_scope(ctx);
3691
3692 oberon_module_t * module;
3693 module = calloc(1, sizeof *module);
3694 module -> decl = module_scope;
3695 module -> next = ctx -> module_list;
3696
3697 ctx -> mod = module;
3698 ctx -> module_list = module;
3699
3700 oberon_init_scaner(ctx, newcode);
3701 oberon_parse_module(ctx);
3702
3703 module -> ready = 1;
3704
3705 ctx -> code = code;
3706 ctx -> code_index = code_index;
3707 ctx -> c = c;
3708 ctx -> token = token;
3709 ctx -> string = string;
3710 ctx -> integer = integer;
3711 ctx -> real = real;
3712 ctx -> longmode = longmode;
3713 ctx -> decl = decl;
3714 ctx -> mod = mod;
3715
3716 return module;
3717 }
Another attempt to make Oberon compiler
[25/02/2024 19:55:35]
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