Commit | Line | Data |
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8a21415b ML |
1 | /* Copyright (c) 1982 Regents of the University of California */ |
2 | ||
99552332 | 3 | static char sccsid[] = "@(#)symbols.c 1.6 %G%"; |
8a21415b ML |
4 | |
5 | /* | |
6 | * Symbol management. | |
7 | */ | |
8 | ||
9 | #include "defs.h" | |
10 | #include "symbols.h" | |
11 | #include "languages.h" | |
12 | #include "printsym.h" | |
13 | #include "tree.h" | |
14 | #include "operators.h" | |
15 | #include "eval.h" | |
16 | #include "mappings.h" | |
17 | #include "events.h" | |
18 | #include "process.h" | |
19 | #include "runtime.h" | |
20 | #include "machine.h" | |
21 | #include "names.h" | |
22 | ||
23 | #ifndef public | |
24 | typedef struct Symbol *Symbol; | |
25 | ||
26 | #include "machine.h" | |
27 | #include "names.h" | |
28 | #include "languages.h" | |
29 | ||
30 | /* | |
31 | * Symbol classes | |
32 | */ | |
33 | ||
34 | typedef enum { | |
35 | BADUSE, CONST, TYPE, VAR, ARRAY, PTRFILE, RECORD, FIELD, | |
36 | PROC, FUNC, FVAR, REF, PTR, FILET, SET, RANGE, | |
37 | LABEL, WITHPTR, SCAL, STR, PROG, IMPROPER, VARNT, | |
38 | FPROC, FFUNC, MODULE, TYPEREF, TAG | |
39 | } Symclass; | |
40 | ||
41 | struct Symbol { | |
42 | Name name; | |
43 | Language language; | |
44 | Symclass class : 8; | |
45 | Integer level : 8; | |
46 | Symbol type; | |
47 | Symbol chain; | |
48 | union { | |
49 | int offset; /* variable address */ | |
50 | long iconval; /* integer constant value */ | |
51 | double fconval; /* floating constant value */ | |
52 | struct { /* field offset and size (both in bits) */ | |
53 | int offset; | |
54 | int length; | |
55 | } field; | |
56 | struct { /* range bounds */ | |
57 | long lower; | |
58 | long upper; | |
59 | } rangev; | |
5455a470 ML |
60 | struct { |
61 | int offset : 16; /* offset for of function value */ | |
62 | Boolean src : 16; /* true if there is source line info */ | |
63 | Address beginaddr; /* address of function code */ | |
8a21415b ML |
64 | } funcv; |
65 | struct { /* variant record info */ | |
66 | int size; | |
67 | Symbol vtorec; | |
68 | Symbol vtag; | |
69 | } varnt; | |
70 | } symvalue; | |
71 | Symbol block; /* symbol containing this symbol */ | |
72 | Symbol next_sym; /* hash chain */ | |
73 | }; | |
74 | ||
75 | /* | |
76 | * Basic types. | |
77 | */ | |
78 | ||
79 | Symbol t_boolean; | |
80 | Symbol t_char; | |
81 | Symbol t_int; | |
82 | Symbol t_real; | |
83 | Symbol t_nil; | |
84 | ||
85 | Symbol program; | |
86 | Symbol curfunc; | |
87 | ||
88 | #define symname(s) ident(s->name) | |
89 | #define codeloc(f) ((f)->symvalue.funcv.beginaddr) | |
90 | #define isblock(s) (Boolean) ( \ | |
91 | s->class == FUNC or s->class == PROC or \ | |
92 | s->class == MODULE or s->class == PROG \ | |
93 | ) | |
94 | ||
5455a470 ML |
95 | #define nosource(f) (not (f)->symvalue.funcv.src) |
96 | ||
8a21415b ML |
97 | #include "tree.h" |
98 | ||
99 | /* | |
100 | * Some macros to make finding a symbol with certain attributes. | |
101 | */ | |
102 | ||
103 | #define find(s, withname) \ | |
104 | { \ | |
105 | s = lookup(withname); \ | |
106 | while (s != nil and not (s->name == (withname) and | |
107 | ||
108 | #define where /* qualification */ | |
109 | ||
110 | #define endfind(s) )) { \ | |
111 | s = s->next_sym; \ | |
112 | } \ | |
113 | } | |
114 | ||
115 | #endif | |
116 | ||
117 | /* | |
118 | * Symbol table structure currently does not support deletions. | |
119 | */ | |
120 | ||
121 | #define HASHTABLESIZE 2003 | |
122 | ||
123 | private Symbol hashtab[HASHTABLESIZE]; | |
124 | ||
125 | #define hash(name) ((((unsigned) name) >> 2) mod HASHTABLESIZE) | |
126 | ||
127 | /* | |
128 | * Allocate a new symbol. | |
129 | */ | |
130 | ||
74dabb40 | 131 | #define SYMBLOCKSIZE 100 |
8a21415b ML |
132 | |
133 | typedef struct Sympool { | |
134 | struct Symbol sym[SYMBLOCKSIZE]; | |
135 | struct Sympool *prevpool; | |
136 | } *Sympool; | |
137 | ||
138 | private Sympool sympool = nil; | |
139 | private Integer nleft = 0; | |
8a21415b ML |
140 | |
141 | public Symbol symbol_alloc() | |
142 | { | |
143 | register Sympool newpool; | |
144 | ||
145 | if (nleft <= 0) { | |
146 | newpool = new(Sympool); | |
74dabb40 | 147 | bzero(newpool, sizeof(newpool)); |
8a21415b ML |
148 | newpool->prevpool = sympool; |
149 | sympool = newpool; | |
150 | nleft = SYMBLOCKSIZE; | |
151 | } | |
152 | --nleft; | |
153 | return &(sympool->sym[nleft]); | |
154 | } | |
155 | ||
156 | /* | |
157 | * Free all the symbols currently allocated. | |
158 | */ | |
159 | ||
160 | public symbol_free() | |
161 | { | |
162 | Sympool s, t; | |
163 | register Integer i; | |
164 | ||
165 | s = sympool; | |
166 | while (s != nil) { | |
167 | t = s->prevpool; | |
168 | dispose(s); | |
169 | s = t; | |
170 | } | |
171 | for (i = 0; i < HASHTABLESIZE; i++) { | |
172 | hashtab[i] = nil; | |
173 | } | |
174 | sympool = nil; | |
175 | nleft = 0; | |
176 | } | |
177 | ||
178 | /* | |
179 | * Create a new symbol with the given attributes. | |
180 | */ | |
181 | ||
182 | public Symbol newSymbol(name, blevel, class, type, chain) | |
183 | Name name; | |
184 | Integer blevel; | |
185 | Symclass class; | |
186 | Symbol type; | |
187 | Symbol chain; | |
188 | { | |
189 | register Symbol s; | |
190 | ||
191 | s = symbol_alloc(); | |
192 | s->name = name; | |
193 | s->level = blevel; | |
194 | s->class = class; | |
195 | s->type = type; | |
196 | s->chain = chain; | |
197 | return s; | |
198 | } | |
199 | ||
200 | /* | |
201 | * Insert a symbol into the hash table. | |
202 | */ | |
203 | ||
204 | public Symbol insert(name) | |
205 | Name name; | |
206 | { | |
207 | register Symbol s; | |
208 | register unsigned int h; | |
209 | ||
210 | h = hash(name); | |
211 | s = symbol_alloc(); | |
212 | s->name = name; | |
213 | s->next_sym = hashtab[h]; | |
214 | hashtab[h] = s; | |
215 | return s; | |
216 | } | |
217 | ||
218 | /* | |
219 | * Symbol lookup. | |
220 | */ | |
221 | ||
222 | public Symbol lookup(name) | |
223 | Name name; | |
224 | { | |
225 | register Symbol s; | |
226 | register unsigned int h; | |
227 | ||
228 | h = hash(name); | |
229 | s = hashtab[h]; | |
230 | while (s != nil and s->name != name) { | |
231 | s = s->next_sym; | |
232 | } | |
233 | return s; | |
234 | } | |
235 | ||
236 | /* | |
237 | * Dump out all the variables associated with the given | |
238 | * procedure, function, or program at the given recursive level. | |
239 | * | |
240 | * This is quite inefficient. We traverse the entire symbol table | |
241 | * each time we're called. The assumption is that this routine | |
242 | * won't be called frequently enough to merit improved performance. | |
243 | */ | |
244 | ||
245 | public dumpvars(f, frame) | |
246 | Symbol f; | |
247 | Frame frame; | |
248 | { | |
249 | register Integer i; | |
250 | register Symbol s; | |
251 | ||
252 | for (i = 0; i < HASHTABLESIZE; i++) { | |
253 | for (s = hashtab[i]; s != nil; s = s->next_sym) { | |
254 | if (container(s) == f) { | |
255 | if (should_print(s)) { | |
256 | printv(s, frame); | |
257 | putchar('\n'); | |
258 | } else if (s->class == MODULE) { | |
259 | dumpvars(s, frame); | |
260 | } | |
261 | } | |
262 | } | |
263 | } | |
264 | } | |
265 | ||
266 | /* | |
267 | * Create a builtin type. | |
268 | * Builtin types are circular in that btype->type->type = btype. | |
269 | */ | |
270 | ||
271 | public Symbol maketype(name, lower, upper) | |
272 | String name; | |
273 | long lower; | |
274 | long upper; | |
275 | { | |
276 | register Symbol s; | |
277 | ||
278 | s = newSymbol(identname(name, true), 0, TYPE, nil, nil); | |
279 | s->language = findlanguage(".c"); | |
280 | s->type = newSymbol(nil, 0, RANGE, s, nil); | |
281 | s->type->symvalue.rangev.lower = lower; | |
282 | s->type->symvalue.rangev.upper = upper; | |
283 | return s; | |
284 | } | |
285 | ||
286 | /* | |
287 | * These functions are now compiled inline. | |
288 | * | |
289 | * public String symname(s) | |
290 | Symbol s; | |
291 | { | |
292 | checkref(s); | |
293 | return ident(s->name); | |
294 | } | |
295 | ||
296 | * | |
297 | * public Address codeloc(f) | |
298 | Symbol f; | |
299 | { | |
300 | checkref(f); | |
301 | if (not isblock(f)) { | |
302 | panic("codeloc: \"%s\" is not a block", ident(f->name)); | |
303 | } | |
304 | return f->symvalue.funcv.beginaddr; | |
305 | } | |
306 | * | |
307 | */ | |
308 | ||
309 | /* | |
310 | * Reduce type to avoid worrying about type names. | |
311 | */ | |
312 | ||
313 | public Symbol rtype(type) | |
314 | Symbol type; | |
315 | { | |
316 | register Symbol t; | |
317 | ||
318 | t = type; | |
319 | if (t != nil) { | |
320 | if (t->class == VAR or t->class == FIELD) { | |
321 | t = t->type; | |
322 | } | |
323 | while (t->class == TYPE or t->class == TAG) { | |
324 | t = t->type; | |
325 | } | |
326 | } | |
327 | return t; | |
328 | } | |
329 | ||
330 | public Integer level(s) | |
331 | Symbol s; | |
332 | { | |
333 | checkref(s); | |
334 | return s->level; | |
335 | } | |
336 | ||
337 | public Symbol container(s) | |
338 | Symbol s; | |
339 | { | |
340 | checkref(s); | |
341 | return s->block; | |
342 | } | |
343 | ||
344 | /* | |
345 | * Return the object address of the given symbol. | |
346 | * | |
347 | * There are the following possibilities: | |
348 | * | |
349 | * globals - just take offset | |
350 | * locals - take offset from locals base | |
351 | * arguments - take offset from argument base | |
352 | * register - offset is register number | |
353 | */ | |
354 | ||
355 | #define isglobal(s) (s->level == 1 or s->level == 2) | |
356 | #define islocaloff(s) (s->level >= 3 and s->symvalue.offset < 0) | |
357 | #define isparamoff(s) (s->level >= 3 and s->symvalue.offset >= 0) | |
358 | #define isreg(s) (s->level < 0) | |
359 | ||
360 | public Address address(s, frame) | |
361 | Symbol s; | |
362 | Frame frame; | |
363 | { | |
364 | register Frame frp; | |
365 | register Address addr; | |
366 | register Symbol cur; | |
367 | ||
368 | checkref(s); | |
369 | if (not isactive(s->block)) { | |
370 | error("\"%s\" is not currently defined", symname(s)); | |
371 | } else if (isglobal(s)) { | |
372 | addr = s->symvalue.offset; | |
373 | } else { | |
374 | frp = frame; | |
375 | if (frp == nil) { | |
376 | cur = s->block; | |
377 | while (cur != nil and cur->class == MODULE) { | |
378 | cur = cur->block; | |
379 | } | |
380 | if (cur == nil) { | |
381 | cur = whatblock(pc); | |
382 | } | |
383 | frp = findframe(cur); | |
384 | if (frp == nil) { | |
385 | panic("unexpected nil frame for \"%s\"", symname(s)); | |
386 | } | |
387 | } | |
388 | if (islocaloff(s)) { | |
389 | addr = locals_base(frp) + s->symvalue.offset; | |
390 | } else if (isparamoff(s)) { | |
391 | addr = args_base(frp) + s->symvalue.offset; | |
392 | } else if (isreg(s)) { | |
393 | addr = savereg(s->symvalue.offset, frp); | |
394 | } else { | |
395 | panic("address: bad symbol \"%s\"", symname(s)); | |
396 | } | |
397 | } | |
398 | return addr; | |
399 | } | |
400 | ||
401 | /* | |
402 | * Define a symbol used to access register values. | |
403 | */ | |
404 | ||
405 | public defregname(n, r) | |
406 | Name n; | |
407 | Integer r; | |
408 | { | |
409 | register Symbol s, t; | |
410 | ||
411 | s = insert(n); | |
412 | t = newSymbol(nil, 0, PTR, t_int, nil); | |
413 | t->language = findlanguage(".s"); | |
414 | s->language = t->language; | |
415 | s->class = VAR; | |
416 | s->level = -3; | |
417 | s->type = t; | |
418 | s->block = program; | |
419 | s->symvalue.offset = r; | |
420 | } | |
421 | ||
422 | /* | |
423 | * Resolve an "abstract" type reference. | |
424 | * | |
425 | * It is possible in C to define a pointer to a type, but never define | |
426 | * the type in a particular source file. Here we try to resolve | |
427 | * the type definition. This is problematic, it is possible to | |
428 | * have multiple, different definitions for the same name type. | |
429 | */ | |
430 | ||
431 | public findtype(s) | |
432 | Symbol s; | |
433 | { | |
434 | register Symbol t, u, prev; | |
435 | ||
436 | u = s; | |
437 | prev = nil; | |
438 | while (u != nil and u->class != BADUSE) { | |
439 | if (u->name != nil) { | |
440 | prev = u; | |
441 | } | |
442 | u = u->type; | |
443 | } | |
444 | if (prev == nil) { | |
445 | error("couldn't find link to type reference"); | |
446 | } | |
447 | find(t, prev->name) where | |
448 | t->type != nil and t->class == prev->class and | |
449 | t->type->class != BADUSE and t->block->class == MODULE | |
450 | endfind(t); | |
451 | if (t == nil) { | |
452 | error("couldn't resolve reference"); | |
453 | } else { | |
454 | prev->type = t->type; | |
455 | } | |
456 | } | |
457 | ||
458 | /* | |
459 | * Find the size in bytes of the given type. | |
460 | * | |
461 | * This is probably the WRONG thing to do. The size should be kept | |
462 | * as an attribute in the symbol information as is done for structures | |
463 | * and fields. I haven't gotten around to cleaning this up yet. | |
464 | */ | |
465 | ||
466 | #define MINCHAR -128 | |
467 | #define MAXCHAR 127 | |
99552332 | 468 | #define MAXUCHAR 255 |
8a21415b ML |
469 | #define MINSHORT -32768 |
470 | #define MAXSHORT 32767 | |
99552332 | 471 | #define MAXUSHORT 65535L |
8a21415b ML |
472 | |
473 | public Integer size(sym) | |
474 | Symbol sym; | |
475 | { | |
476 | register Symbol s, t; | |
477 | register int nel, elsize; | |
478 | long lower, upper; | |
479 | int r; | |
480 | ||
481 | t = sym; | |
482 | checkref(t); | |
483 | switch (t->class) { | |
484 | case RANGE: | |
485 | lower = t->symvalue.rangev.lower; | |
486 | upper = t->symvalue.rangev.upper; | |
487 | if (upper == 0 and lower > 0) { /* real */ | |
488 | r = lower; | |
99552332 ML |
489 | } else if ( |
490 | (lower >= MINCHAR and upper <= MAXCHAR) or | |
491 | (lower >= 0 and upper <= MAXUCHAR) | |
492 | ) { | |
8a21415b | 493 | r = sizeof(char); |
99552332 ML |
494 | } else if ( |
495 | (lower >= MINSHORT and upper <= MAXSHORT) or | |
496 | (lower >= 0 and upper <= MAXUSHORT) | |
497 | ) { | |
8a21415b ML |
498 | r = sizeof(short); |
499 | } else { | |
500 | r = sizeof(long); | |
501 | } | |
502 | break; | |
503 | ||
504 | case ARRAY: | |
505 | elsize = size(t->type); | |
506 | nel = 1; | |
507 | for (t = t->chain; t != nil; t = t->chain) { | |
508 | s = rtype(t); | |
509 | lower = s->symvalue.rangev.lower; | |
510 | upper = s->symvalue.rangev.upper; | |
511 | nel *= (upper-lower+1); | |
512 | } | |
513 | r = nel*elsize; | |
514 | break; | |
515 | ||
516 | case VAR: | |
517 | case FVAR: | |
518 | r = size(t->type); | |
99552332 | 519 | if (r < sizeof(Word) and isparam(t)) { |
8a21415b ML |
520 | r = sizeof(Word); |
521 | } | |
522 | break; | |
523 | ||
524 | case CONST: | |
525 | r = size(t->type); | |
526 | break; | |
527 | ||
528 | case TYPE: | |
529 | if (t->type->class == PTR and t->type->type->class == BADUSE) { | |
530 | findtype(t); | |
531 | } | |
532 | r = size(t->type); | |
533 | break; | |
534 | ||
535 | case TAG: | |
536 | r = size(t->type); | |
537 | break; | |
538 | ||
539 | case FIELD: | |
540 | r = (t->symvalue.field.length + 7) div 8; | |
541 | break; | |
542 | ||
543 | case RECORD: | |
544 | case VARNT: | |
545 | r = t->symvalue.offset; | |
546 | if (r == 0 and t->chain != nil) { | |
547 | panic("missing size information for record"); | |
548 | } | |
549 | break; | |
550 | ||
551 | case PTR: | |
552 | case REF: | |
553 | case FILET: | |
554 | r = sizeof(Word); | |
555 | break; | |
556 | ||
557 | case SCAL: | |
558 | if (t->symvalue.iconval > 255) { | |
559 | r = sizeof(short); | |
560 | } else { | |
561 | r = sizeof(char); | |
562 | } | |
563 | break; | |
564 | ||
565 | case FPROC: | |
566 | case FFUNC: | |
567 | r = sizeof(Word); | |
568 | break; | |
569 | ||
570 | case PROC: | |
571 | case FUNC: | |
572 | case MODULE: | |
573 | case PROG: | |
574 | r = sizeof(Symbol); | |
575 | break; | |
576 | ||
577 | default: | |
578 | if (ord(t->class) > ord(TYPEREF)) { | |
579 | panic("size: bad class (%d)", ord(t->class)); | |
580 | } else { | |
581 | error("improper operation on a %s", classname(t)); | |
582 | } | |
583 | /* NOTREACHED */ | |
584 | } | |
585 | if (r < sizeof(Word) and isparam(sym)) { | |
586 | r = sizeof(Word); | |
587 | } | |
588 | return r; | |
589 | } | |
590 | ||
591 | /* | |
592 | * Test if a symbol is a parameter. This is true if there | |
593 | * is a cycle from s->block to s via chain pointers. | |
594 | */ | |
595 | ||
596 | public Boolean isparam(s) | |
597 | Symbol s; | |
598 | { | |
599 | register Symbol t; | |
600 | ||
601 | t = s->block; | |
602 | while (t != nil and t != s) { | |
603 | t = t->chain; | |
604 | } | |
605 | return (Boolean) (t != nil); | |
606 | } | |
607 | ||
608 | /* | |
609 | * Test if a symbol is a var parameter, i.e. has class REF. | |
610 | */ | |
611 | ||
612 | public Boolean isvarparam(s) | |
613 | Symbol s; | |
614 | { | |
615 | return (Boolean) (s->class == REF); | |
616 | } | |
617 | ||
618 | /* | |
619 | * Test if a symbol is a variable (actually any addressible quantity | |
620 | * with do). | |
621 | */ | |
622 | ||
623 | public Boolean isvariable(s) | |
624 | register Symbol s; | |
625 | { | |
626 | return (Boolean) (s->class == VAR or s->class == FVAR or s->class == REF); | |
627 | } | |
628 | ||
629 | /* | |
630 | * Test if a symbol is a block, e.g. function, procedure, or the | |
631 | * main program. | |
632 | * | |
633 | * This function is now expanded inline for efficiency. | |
634 | * | |
635 | * public Boolean isblock(s) | |
636 | register Symbol s; | |
637 | { | |
638 | return (Boolean) ( | |
639 | s->class == FUNC or s->class == PROC or | |
640 | s->class == MODULE or s->class == PROG | |
641 | ); | |
642 | } | |
643 | * | |
644 | */ | |
645 | ||
646 | /* | |
647 | * Test if a symbol is a module. | |
648 | */ | |
649 | ||
650 | public Boolean ismodule(s) | |
651 | register Symbol s; | |
652 | { | |
653 | return (Boolean) (s->class == MODULE); | |
654 | } | |
655 | ||
656 | /* | |
657 | * Test if a symbol is builtin, that is, a predefined type or | |
658 | * reserved word. | |
659 | */ | |
660 | ||
661 | public Boolean isbuiltin(s) | |
662 | register Symbol s; | |
663 | { | |
664 | return (Boolean) (s->level == 0 and s->class != PROG and s->class != VAR); | |
665 | } | |
666 | ||
667 | /* | |
668 | * Test if two types match. | |
669 | * Equivalent names implies a match in any language. | |
670 | * | |
671 | * Special symbols must be handled with care. | |
672 | */ | |
673 | ||
674 | public Boolean compatible(t1, t2) | |
675 | register Symbol t1, t2; | |
676 | { | |
677 | Boolean b; | |
678 | ||
679 | if (t1 == t2) { | |
680 | b = true; | |
681 | } else if (t1 == nil or t2 == nil) { | |
682 | b = false; | |
683 | } else if (t1 == procsym) { | |
684 | b = isblock(t2); | |
685 | } else if (t2 == procsym) { | |
686 | b = isblock(t1); | |
687 | } else if (t1->language == nil) { | |
688 | b = (Boolean) (t2->language == nil or | |
689 | (*language_op(t2->language, L_TYPEMATCH))(t1, t2)); | |
690 | } else { | |
691 | b = (Boolean) (*language_op(t1->language, L_TYPEMATCH))(t1, t2); | |
692 | } | |
693 | return b; | |
694 | } | |
695 | ||
696 | /* | |
697 | * Check for a type of the given name. | |
698 | */ | |
699 | ||
700 | public Boolean istypename(type, name) | |
701 | Symbol type; | |
702 | String name; | |
703 | { | |
704 | Symbol t; | |
705 | Boolean b; | |
706 | ||
707 | t = type; | |
708 | checkref(t); | |
709 | b = (Boolean) ( | |
710 | t->class == TYPE and t->name == identname(name, true) | |
711 | ); | |
712 | return b; | |
713 | } | |
714 | ||
715 | /* | |
716 | * Test if the name of a symbol is uniquely defined or not. | |
717 | */ | |
718 | ||
719 | public Boolean isambiguous(s) | |
720 | register Symbol s; | |
721 | { | |
722 | register Symbol t; | |
723 | ||
724 | find(t, s->name) where t != s endfind(t); | |
725 | return (Boolean) (t != nil); | |
726 | } | |
727 | ||
728 | typedef char *Arglist; | |
729 | ||
730 | #define nextarg(type) ((type *) (ap += sizeof(type)))[-1] | |
731 | ||
732 | private Symbol mkstring(); | |
733 | private Symbol namenode(); | |
734 | ||
735 | /* | |
736 | * Determine the type of a parse tree. | |
737 | * Also make some symbol-dependent changes to the tree such as | |
738 | * changing removing RVAL nodes for constant symbols. | |
739 | */ | |
740 | ||
741 | public assigntypes(p) | |
742 | register Node p; | |
743 | { | |
744 | register Node p1; | |
745 | register Symbol s; | |
746 | ||
747 | switch (p->op) { | |
748 | case O_SYM: | |
749 | p->nodetype = namenode(p); | |
750 | break; | |
751 | ||
752 | case O_LCON: | |
753 | p->nodetype = t_int; | |
754 | break; | |
755 | ||
756 | case O_FCON: | |
757 | p->nodetype = t_real; | |
758 | break; | |
759 | ||
760 | case O_SCON: | |
761 | p->value.scon = strdup(p->value.scon); | |
762 | s = mkstring(p->value.scon); | |
763 | if (s == t_char) { | |
764 | p->op = O_LCON; | |
765 | p->value.lcon = p->value.scon[0]; | |
766 | } | |
767 | p->nodetype = s; | |
768 | break; | |
769 | ||
770 | case O_INDIR: | |
771 | p1 = p->value.arg[0]; | |
772 | chkclass(p1, PTR); | |
773 | p->nodetype = rtype(p1->nodetype)->type; | |
774 | break; | |
775 | ||
776 | case O_DOT: | |
777 | p->nodetype = p->value.arg[1]->value.sym; | |
778 | break; | |
779 | ||
780 | case O_RVAL: | |
781 | p1 = p->value.arg[0]; | |
782 | p->nodetype = p1->nodetype; | |
783 | if (p1->op == O_SYM) { | |
784 | if (p1->nodetype->class == FUNC) { | |
785 | p->op = O_CALL; | |
786 | p->value.arg[1] = nil; | |
787 | } else if (p1->value.sym->class == CONST) { | |
788 | if (compatible(p1->value.sym->type, t_real)) { | |
789 | p->op = O_FCON; | |
790 | p->value.fcon = p1->value.sym->symvalue.fconval; | |
791 | p->nodetype = t_real; | |
792 | dispose(p1); | |
793 | } else { | |
794 | p->op = O_LCON; | |
795 | p->value.lcon = p1->value.sym->symvalue.iconval; | |
796 | p->nodetype = p1->value.sym->type; | |
797 | dispose(p1); | |
798 | } | |
799 | } else if (isreg(p1->value.sym)) { | |
800 | p->op = O_SYM; | |
801 | p->value.sym = p1->value.sym; | |
802 | dispose(p1); | |
803 | } | |
804 | } else if (p1->op == O_INDIR and p1->value.arg[0]->op == O_SYM) { | |
805 | s = p1->value.arg[0]->value.sym; | |
806 | if (isreg(s)) { | |
807 | p1->op = O_SYM; | |
808 | dispose(p1->value.arg[0]); | |
809 | p1->value.sym = s; | |
810 | p1->nodetype = s; | |
811 | } | |
812 | } | |
813 | break; | |
814 | ||
815 | /* | |
816 | * Perform a cast if the call is of the form "type(expr)". | |
817 | */ | |
818 | case O_CALL: | |
819 | p1 = p->value.arg[0]; | |
74dabb40 ML |
820 | p->nodetype = rtype(p1->nodetype)->type; |
821 | break; | |
822 | ||
823 | case O_TYPERENAME: | |
824 | p->nodetype = p->value.arg[1]->nodetype; | |
8a21415b ML |
825 | break; |
826 | ||
827 | case O_ITOF: | |
828 | p->nodetype = t_real; | |
829 | break; | |
830 | ||
831 | case O_NEG: | |
832 | s = p->value.arg[0]->nodetype; | |
833 | if (not compatible(s, t_int)) { | |
834 | if (not compatible(s, t_real)) { | |
835 | beginerrmsg(); | |
836 | prtree(stderr, p->value.arg[0]); | |
837 | fprintf(stderr, "is improper type"); | |
838 | enderrmsg(); | |
839 | } else { | |
840 | p->op = O_NEGF; | |
841 | } | |
842 | } | |
843 | p->nodetype = s; | |
844 | break; | |
845 | ||
846 | case O_ADD: | |
847 | case O_SUB: | |
848 | case O_MUL: | |
849 | case O_LT: | |
850 | case O_LE: | |
851 | case O_GT: | |
852 | case O_GE: | |
853 | case O_EQ: | |
854 | case O_NE: | |
855 | { | |
856 | Boolean t1real, t2real; | |
857 | Symbol t1, t2; | |
858 | ||
859 | t1 = rtype(p->value.arg[0]->nodetype); | |
860 | t2 = rtype(p->value.arg[1]->nodetype); | |
861 | t1real = compatible(t1, t_real); | |
862 | t2real = compatible(t2, t_real); | |
863 | if (t1real or t2real) { | |
864 | p->op = (Operator) (ord(p->op) + 1); | |
865 | if (not t1real) { | |
866 | p->value.arg[0] = build(O_ITOF, p->value.arg[0]); | |
867 | } else if (not t2real) { | |
868 | p->value.arg[1] = build(O_ITOF, p->value.arg[1]); | |
869 | } | |
870 | } else { | |
871 | if (t1real) { | |
872 | convert(&(p->value.arg[0]), t_int, O_NOP); | |
873 | } | |
874 | if (t2real) { | |
875 | convert(&(p->value.arg[1]), t_int, O_NOP); | |
876 | } | |
877 | } | |
878 | if (ord(p->op) >= ord(O_LT)) { | |
879 | p->nodetype = t_boolean; | |
880 | } else { | |
881 | if (t1real or t2real) { | |
882 | p->nodetype = t_real; | |
883 | } else { | |
884 | p->nodetype = t_int; | |
885 | } | |
886 | } | |
887 | break; | |
888 | } | |
889 | ||
890 | case O_DIVF: | |
891 | convert(&(p->value.arg[0]), t_real, O_ITOF); | |
892 | convert(&(p->value.arg[1]), t_real, O_ITOF); | |
893 | p->nodetype = t_real; | |
894 | break; | |
895 | ||
896 | case O_DIV: | |
897 | case O_MOD: | |
898 | convert(&(p->value.arg[0]), t_int, O_NOP); | |
899 | convert(&(p->value.arg[1]), t_int, O_NOP); | |
900 | p->nodetype = t_int; | |
901 | break; | |
902 | ||
903 | case O_AND: | |
904 | case O_OR: | |
905 | chkboolean(p->value.arg[0]); | |
906 | chkboolean(p->value.arg[1]); | |
907 | p->nodetype = t_boolean; | |
908 | break; | |
909 | ||
910 | case O_QLINE: | |
911 | p->nodetype = t_int; | |
912 | break; | |
913 | ||
914 | default: | |
915 | p->nodetype = nil; | |
916 | break; | |
917 | } | |
918 | } | |
919 | ||
920 | /* | |
921 | * Create a node for a name. The symbol for the name has already | |
922 | * been chosen, either implicitly with "which" or explicitly from | |
923 | * the dot routine. | |
924 | */ | |
925 | ||
926 | private Symbol namenode(p) | |
927 | Node p; | |
928 | { | |
929 | register Symbol r, s; | |
930 | register Node np; | |
931 | ||
932 | s = p->value.sym; | |
933 | if (s->class == REF) { | |
934 | np = new(Node); | |
935 | np->op = p->op; | |
936 | np->nodetype = s; | |
937 | np->value.sym = s; | |
938 | p->op = O_INDIR; | |
939 | p->value.arg[0] = np; | |
940 | } | |
941 | /* | |
942 | * Old way | |
943 | * | |
944 | if (s->class == CONST or s->class == VAR or s->class == FVAR) { | |
945 | r = s->type; | |
946 | } else { | |
947 | r = s; | |
948 | } | |
949 | * | |
950 | */ | |
951 | return s; | |
952 | } | |
953 | ||
954 | /* | |
955 | * Convert a tree to a type via a conversion operator; | |
956 | * if this isn't possible generate an error. | |
957 | * | |
958 | * Note the tree is call by address, hence the #define below. | |
959 | */ | |
960 | ||
961 | private convert(tp, typeto, op) | |
962 | Node *tp; | |
963 | Symbol typeto; | |
964 | Operator op; | |
965 | { | |
966 | #define tree (*tp) | |
967 | ||
968 | Symbol s; | |
969 | ||
970 | s = rtype(tree->nodetype); | |
971 | typeto = rtype(typeto); | |
972 | if (compatible(typeto, t_real) and compatible(s, t_int)) { | |
973 | tree = build(op, tree); | |
974 | } else if (not compatible(s, typeto)) { | |
975 | beginerrmsg(); | |
976 | prtree(stderr, s); | |
977 | fprintf(stderr, " is improper type"); | |
978 | enderrmsg(); | |
979 | } else if (op != O_NOP and s != typeto) { | |
980 | tree = build(op, tree); | |
981 | } | |
982 | ||
983 | #undef tree | |
984 | } | |
985 | ||
986 | /* | |
987 | * Construct a node for the dot operator. | |
988 | * | |
989 | * If the left operand is not a record, but rather a procedure | |
990 | * or function, then we interpret the "." as referencing an | |
991 | * "invisible" variable; i.e. a variable within a dynamically | |
992 | * active block but not within the static scope of the current procedure. | |
993 | */ | |
994 | ||
995 | public Node dot(record, fieldname) | |
996 | Node record; | |
997 | Name fieldname; | |
998 | { | |
999 | register Node p; | |
1000 | register Symbol s, t; | |
1001 | ||
1002 | if (isblock(record->nodetype)) { | |
1003 | find(s, fieldname) where | |
1004 | s->block == record->nodetype and | |
1005 | s->class != FIELD and s->class != TAG | |
1006 | endfind(s); | |
1007 | if (s == nil) { | |
1008 | beginerrmsg(); | |
1009 | fprintf(stderr, "\"%s\" is not defined in ", ident(fieldname)); | |
1010 | printname(stderr, record->nodetype); | |
1011 | enderrmsg(); | |
1012 | } | |
1013 | p = new(Node); | |
1014 | p->op = O_SYM; | |
1015 | p->value.sym = s; | |
1016 | p->nodetype = namenode(p); | |
1017 | } else { | |
1018 | p = record; | |
1019 | t = rtype(p->nodetype); | |
1020 | if (t->class == PTR) { | |
1021 | s = findfield(fieldname, t->type); | |
1022 | } else { | |
1023 | s = findfield(fieldname, t); | |
1024 | } | |
1025 | if (s == nil) { | |
1026 | beginerrmsg(); | |
1027 | fprintf(stderr, "\"%s\" is not a field in ", ident(fieldname)); | |
1028 | prtree(stderr, record); | |
1029 | enderrmsg(); | |
1030 | } | |
1031 | if (t->class == PTR and not isreg(record->nodetype)) { | |
1032 | p = build(O_INDIR, record); | |
1033 | } | |
1034 | p = build(O_DOT, p, build(O_SYM, s)); | |
1035 | } | |
1036 | return p; | |
1037 | } | |
1038 | ||
1039 | /* | |
1040 | * Return a tree corresponding to an array reference and do the | |
1041 | * error checking. | |
1042 | */ | |
1043 | ||
1044 | public Node subscript(a, slist) | |
1045 | Node a, slist; | |
1046 | { | |
1047 | register Symbol t; | |
1048 | register Node p; | |
1049 | Symbol etype, atype, eltype; | |
483c4884 | 1050 | Node esub, r; |
8a21415b | 1051 | |
483c4884 | 1052 | r = a; |
8a21415b | 1053 | t = rtype(a->nodetype); |
483c4884 ML |
1054 | eltype = t->type; |
1055 | if (t->class == PTR) { | |
1056 | p = slist->value.arg[0]; | |
1057 | if (not compatible(p->nodetype, t_int)) { | |
1058 | beginerrmsg(); | |
1059 | fprintf(stderr, "bad type for subscript of "); | |
1060 | prtree(stderr, a); | |
1061 | enderrmsg(); | |
1062 | } | |
1063 | r = build(O_MUL, p, build(O_LCON, (long) size(eltype))); | |
1064 | r = build(O_ADD, build(O_RVAL, a), r); | |
1065 | r->nodetype = eltype; | |
1066 | } else if (t->class != ARRAY) { | |
8a21415b ML |
1067 | beginerrmsg(); |
1068 | prtree(stderr, a); | |
1069 | fprintf(stderr, " is not an array"); | |
1070 | enderrmsg(); | |
483c4884 ML |
1071 | } else { |
1072 | p = slist; | |
1073 | t = t->chain; | |
1074 | for (; p != nil and t != nil; p = p->value.arg[1], t = t->chain) { | |
1075 | esub = p->value.arg[0]; | |
1076 | etype = rtype(esub->nodetype); | |
1077 | atype = rtype(t); | |
1078 | if (not compatible(atype, etype)) { | |
1079 | beginerrmsg(); | |
1080 | fprintf(stderr, "subscript "); | |
1081 | prtree(stderr, esub); | |
1082 | fprintf(stderr, " is the wrong type"); | |
1083 | enderrmsg(); | |
1084 | } | |
1085 | r = build(O_INDEX, r, esub); | |
1086 | r->nodetype = eltype; | |
1087 | } | |
1088 | if (p != nil or t != nil) { | |
8a21415b | 1089 | beginerrmsg(); |
483c4884 ML |
1090 | if (p != nil) { |
1091 | fprintf(stderr, "too many subscripts for "); | |
1092 | } else { | |
1093 | fprintf(stderr, "not enough subscripts for "); | |
1094 | } | |
1095 | prtree(stderr, a); | |
8a21415b ML |
1096 | enderrmsg(); |
1097 | } | |
8a21415b | 1098 | } |
483c4884 | 1099 | return r; |
8a21415b ML |
1100 | } |
1101 | ||
1102 | /* | |
1103 | * Evaluate a subscript index. | |
1104 | */ | |
1105 | ||
1106 | public int evalindex(s, i) | |
1107 | Symbol s; | |
1108 | long i; | |
1109 | { | |
1110 | long lb, ub; | |
1111 | ||
1112 | s = rtype(s)->chain; | |
1113 | lb = s->symvalue.rangev.lower; | |
1114 | ub = s->symvalue.rangev.upper; | |
1115 | if (i < lb or i > ub) { | |
1116 | error("subscript out of range"); | |
1117 | } | |
1118 | return (i - lb); | |
1119 | } | |
1120 | ||
1121 | /* | |
1122 | * Check to see if a tree is boolean-valued, if not it's an error. | |
1123 | */ | |
1124 | ||
1125 | public chkboolean(p) | |
1126 | register Node p; | |
1127 | { | |
1128 | if (p->nodetype != t_boolean) { | |
1129 | beginerrmsg(); | |
1130 | fprintf(stderr, "found "); | |
1131 | prtree(stderr, p); | |
1132 | fprintf(stderr, ", expected boolean expression"); | |
1133 | enderrmsg(); | |
1134 | } | |
1135 | } | |
1136 | ||
1137 | /* | |
1138 | * Check to make sure the given tree has a type of the given class. | |
1139 | */ | |
1140 | ||
1141 | private chkclass(p, class) | |
1142 | Node p; | |
1143 | Symclass class; | |
1144 | { | |
1145 | struct Symbol tmpsym; | |
1146 | ||
1147 | tmpsym.class = class; | |
1148 | if (rtype(p->nodetype)->class != class) { | |
1149 | beginerrmsg(); | |
1150 | fprintf(stderr, "\""); | |
1151 | prtree(stderr, p); | |
1152 | fprintf(stderr, "\" is not a %s", classname(&tmpsym)); | |
1153 | enderrmsg(); | |
1154 | } | |
1155 | } | |
1156 | ||
1157 | /* | |
1158 | * Construct a node for the type of a string. While we're at it, | |
1159 | * scan the string for '' that collapse to ', and chop off the ends. | |
1160 | */ | |
1161 | ||
1162 | private Symbol mkstring(str) | |
1163 | String str; | |
1164 | { | |
1165 | register char *p, *q; | |
1166 | register Symbol s; | |
1167 | ||
1168 | p = str; | |
1169 | q = str; | |
1170 | while (*p != '\0') { | |
1171 | if (*p == '\\') { | |
1172 | ++p; | |
1173 | } | |
1174 | *q = *p; | |
1175 | ++p; | |
1176 | ++q; | |
1177 | } | |
1178 | *q = '\0'; | |
1179 | s = newSymbol(nil, 0, ARRAY, t_char, nil); | |
1180 | s->language = findlanguage(".s"); | |
1181 | s->chain = newSymbol(nil, 0, RANGE, t_int, nil); | |
1182 | s->chain->language = s->language; | |
1183 | s->chain->symvalue.rangev.lower = 1; | |
1184 | s->chain->symvalue.rangev.upper = p - str + 1; | |
1185 | return s; | |
1186 | } | |
1187 | ||
1188 | /* | |
1189 | * Free up the space allocated for a string type. | |
1190 | */ | |
1191 | ||
1192 | public unmkstring(s) | |
1193 | Symbol s; | |
1194 | { | |
1195 | dispose(s->chain); | |
1196 | } | |
1197 | ||
1198 | /* | |
1199 | * Figure out the "current" variable or function being referred to, | |
1200 | * this is either the active one or the most visible from the | |
1201 | * current scope. | |
1202 | */ | |
1203 | ||
1204 | public Symbol which(n) | |
1205 | Name n; | |
1206 | { | |
1207 | register Symbol s, p, t, f; | |
1208 | ||
1209 | find(s, n) where s->class != FIELD and s->class != TAG endfind(s); | |
1210 | if (s == nil) { | |
1211 | s = lookup(n); | |
1212 | } | |
1213 | if (s == nil) { | |
1214 | error("\"%s\" is not defined", ident(n)); | |
1215 | } else if (s == program or isbuiltin(s)) { | |
1216 | t = s; | |
1217 | } else { | |
1218 | /* | |
1219 | * Old way | |
1220 | * | |
1221 | if (not isactive(program)) { | |
1222 | f = program; | |
1223 | } else { | |
1224 | f = whatblock(pc); | |
1225 | if (f == nil) { | |
1226 | panic("no block for addr 0x%x", pc); | |
1227 | } | |
1228 | } | |
1229 | * | |
1230 | * Now start with curfunc. | |
1231 | */ | |
1232 | p = curfunc; | |
1233 | do { | |
1234 | find(t, n) where | |
1235 | t->block == p and t->class != FIELD and t->class != TAG | |
1236 | endfind(t); | |
1237 | p = p->block; | |
1238 | } while (t == nil and p != nil); | |
1239 | if (t == nil) { | |
1240 | t = s; | |
1241 | } | |
1242 | } | |
1243 | return t; | |
1244 | } | |
1245 | ||
1246 | /* | |
1247 | * Find the symbol which is has the same name and scope as the | |
1248 | * given symbol but is of the given field. Return nil if there is none. | |
1249 | */ | |
1250 | ||
1251 | public Symbol findfield(fieldname, record) | |
1252 | Name fieldname; | |
1253 | Symbol record; | |
1254 | { | |
1255 | register Symbol t; | |
1256 | ||
1257 | t = rtype(record)->chain; | |
1258 | while (t != nil and t->name != fieldname) { | |
1259 | t = t->chain; | |
1260 | } | |
1261 | return t; | |
1262 | } |