Commit | Line | Data |
---|---|---|
381c0f0e | 1 | |
52646e6f ML |
2 | /* Copyright (c) 1982 Regents of the University of California */ |
3 | ||
2fd0f574 SL |
4 | static char sccsid[] = "@(#)runtime.c 1.8 8/10/83"; |
5 | ||
6 | static char rcsid[] = "$Header: runtime.c,v 1.3 84/03/27 10:23:40 linton Exp $"; | |
52646e6f ML |
7 | |
8 | /* | |
9 | * Runtime organization dependent routines, mostly dealing with | |
10 | * activation records. | |
11 | */ | |
12 | ||
13 | #include "defs.h" | |
14 | #include "runtime.h" | |
15 | #include "process.h" | |
16 | #include "machine.h" | |
17 | #include "events.h" | |
18 | #include "mappings.h" | |
19 | #include "symbols.h" | |
20 | #include "tree.h" | |
21 | #include "eval.h" | |
22 | #include "operators.h" | |
23 | #include "object.h" | |
381c0f0e | 24 | #include <sys/param.h> |
52646e6f ML |
25 | |
26 | #ifndef public | |
27 | typedef struct Frame *Frame; | |
28 | ||
29 | #include "machine.h" | |
30 | #endif | |
31 | ||
32 | #define NSAVEREG 12 | |
33 | ||
34 | struct Frame { | |
35 | Integer condition_handler; | |
36 | Integer mask; | |
37 | Address save_ap; /* argument pointer */ | |
38 | Address save_fp; /* frame pointer */ | |
39 | Address save_pc; /* program counter */ | |
40 | Word save_reg[NSAVEREG]; /* not necessarily there */ | |
41 | }; | |
42 | ||
2fd0f574 SL |
43 | private Frame curframe = nil; |
44 | private struct Frame curframerec; | |
52646e6f ML |
45 | private Boolean walkingstack = false; |
46 | ||
2fd0f574 SL |
47 | #define frameeq(f1, f2) ((f1)->save_fp == (f2)->save_fp) |
48 | ||
52646e6f ML |
49 | /* |
50 | * Set a frame to the current activation record. | |
51 | */ | |
52 | ||
53 | private getcurframe(frp) | |
54 | register Frame frp; | |
55 | { | |
56 | register int i; | |
57 | ||
58 | checkref(frp); | |
59 | frp->mask = reg(NREG); | |
60 | frp->save_ap = reg(ARGP); | |
61 | frp->save_fp = reg(FRP); | |
551efd5b | 62 | frp->save_pc = reg(PROGCTR) + 1; |
52646e6f ML |
63 | for (i = 0; i < NSAVEREG; i++) { |
64 | frp->save_reg[i] = reg(i); | |
65 | } | |
66 | } | |
67 | ||
68 | /* | |
69 | * Return a pointer to the next activation record up the stack. | |
70 | * Return nil if there is none. | |
71 | * Writes over space pointed to by given argument. | |
72 | */ | |
73 | ||
74 | #define bis(b, n) ((b & (1 << (n))) != 0) | |
75 | ||
76 | private Frame nextframe(frp) | |
77 | Frame frp; | |
78 | { | |
79 | register Frame newfrp; | |
80 | struct Frame frame; | |
81 | register Integer i, j, mask; | |
381c0f0e | 82 | Address prev_frame, callpc; |
316d2228 | 83 | static Integer ntramp = 0; |
52646e6f ML |
84 | |
85 | newfrp = frp; | |
381c0f0e AF |
86 | prev_frame = frp->save_fp; |
87 | ||
316d2228 ML |
88 | /* |
89 | * The check for interrupt generated frames is taken from adb with only | |
90 | * partial understanding. If you're in "sub" and on a sigxxx "sigsub" | |
91 | * gets control, then the stack does NOT look like <main, sub, sigsub>. | |
381c0f0e AF |
92 | * |
93 | * As best I can make out it looks like: | |
316d2228 ML |
94 | * |
95 | * <main, (machine check exception block + sub), sysframe, sigsub>. | |
96 | * | |
97 | * When the signal occurs an exception block and a frame for the routine | |
98 | * in which it occured are pushed on the user stack. Then another frame | |
99 | * is pushed corresponding to a call from the kernel to sigsub. | |
381c0f0e AF |
100 | * |
101 | * The addr in sub at which the exception occured is not in sub.save_pc | |
316d2228 | 102 | * but in the machine check exception block. It is at the magic address |
8d44f3a5 | 103 | * fp + 84. |
381c0f0e AF |
104 | * |
105 | * The current approach ignores the sys_frame (what adb reports as sigtramp) | |
316d2228 ML |
106 | * and takes the pc for sub from the exception block. This allows the |
107 | * "where" command to report <main, sub, sigsub>, which seems reasonable. | |
381c0f0e | 108 | */ |
381c0f0e | 109 | |
316d2228 ML |
110 | nextf: |
111 | dread(&frame, prev_frame, sizeof(struct Frame)); | |
112 | if (ntramp == 1) { | |
8d44f3a5 | 113 | dread(&callpc, prev_frame + 84, sizeof(callpc)); |
316d2228 ML |
114 | } else { |
115 | callpc = frame.save_pc; | |
116 | } | |
52646e6f ML |
117 | if (frame.save_fp == nil) { |
118 | newfrp = nil; | |
316d2228 | 119 | } else if (callpc > 0x80000000 - 0x200 * UPAGES ) { |
381c0f0e AF |
120 | ntramp++; |
121 | prev_frame = frame.save_fp; | |
122 | goto nextf; | |
316d2228 | 123 | } else { |
381c0f0e | 124 | frame.save_pc = callpc; |
316d2228 | 125 | ntramp = 0; |
52646e6f ML |
126 | mask = ((frame.mask >> 16) & 0x0fff); |
127 | j = 0; | |
128 | for (i = 0; i < NSAVEREG; i++) { | |
129 | if (bis(mask, i)) { | |
130 | newfrp->save_reg[i] = frame.save_reg[j]; | |
131 | ++j; | |
132 | } | |
133 | } | |
134 | newfrp->condition_handler = frame.condition_handler; | |
135 | newfrp->mask = mask; | |
136 | newfrp->save_ap = frame.save_ap; | |
137 | newfrp->save_fp = frame.save_fp; | |
138 | newfrp->save_pc = frame.save_pc; | |
139 | } | |
140 | return newfrp; | |
141 | } | |
142 | ||
2fd0f574 SL |
143 | /* |
144 | * Get the current frame information in the given Frame and store the | |
145 | * associated function in the given value-result parameter. | |
146 | */ | |
147 | ||
148 | private getcurfunc (frp, fp) | |
149 | Frame frp; | |
150 | Symbol *fp; | |
151 | { | |
152 | getcurframe(frp); | |
153 | *fp = whatblock(frp->save_pc); | |
154 | } | |
155 | ||
156 | /* | |
157 | * Return the frame associated with the next function up the call stack, or | |
158 | * nil if there is none. The function is returned in a value-result parameter. | |
159 | * For "inline" functions the statically outer function and same frame | |
160 | * are returned. | |
161 | */ | |
162 | ||
163 | private Frame nextfunc (frp, fp) | |
164 | Frame frp; | |
165 | Symbol *fp; | |
166 | { | |
167 | Symbol t; | |
168 | Frame nfrp; | |
169 | ||
170 | t = *fp; | |
171 | checkref(t); | |
172 | if (isinline(t)) { | |
173 | t = container(t); | |
174 | nfrp = frp; | |
175 | } else { | |
176 | nfrp = nextframe(frp); | |
177 | if (nfrp == nil) { | |
178 | t = nil; | |
179 | } else { | |
180 | t = whatblock(nfrp->save_pc); | |
181 | } | |
182 | } | |
183 | *fp = t; | |
184 | return nfrp; | |
185 | } | |
186 | ||
52646e6f ML |
187 | /* |
188 | * Return the frame associated with the given function. | |
189 | * If the function is nil, return the most recently activated frame. | |
190 | * | |
191 | * Static allocation for the frame. | |
192 | */ | |
193 | ||
194 | public Frame findframe(f) | |
195 | Symbol f; | |
196 | { | |
197 | register Frame frp; | |
198 | static struct Frame frame; | |
4fd956ac | 199 | Symbol p; |
52646e6f ML |
200 | |
201 | frp = &frame; | |
202 | getcurframe(frp); | |
912533aa SL |
203 | if (f == nil) |
204 | return (frp); | |
205 | /* | |
206 | * Starting at the current stack frame, | |
207 | * walk backwards looking for a symbol | |
208 | * match. Beware of local blocks which | |
209 | * have a back pointer but no stack frame. | |
210 | */ | |
211 | p = whatblock(frp->save_pc); | |
212 | while (p != f) { | |
213 | if (p == program) { | |
214 | frp = nil; | |
215 | break; | |
216 | } | |
217 | if (isinline(p)) { | |
218 | p = container(p); | |
219 | continue; | |
220 | } | |
221 | frp = nextframe(frp); | |
222 | if (frp == nil) | |
223 | break; | |
224 | p = whatblock(frp->save_pc); | |
52646e6f | 225 | } |
912533aa | 226 | return (frp); |
52646e6f ML |
227 | } |
228 | ||
229 | /* | |
230 | * Find the return address of the current procedure/function. | |
231 | */ | |
232 | ||
233 | public Address return_addr() | |
234 | { | |
235 | Frame frp; | |
236 | Address addr; | |
237 | struct Frame frame; | |
238 | ||
239 | frp = &frame; | |
240 | getcurframe(frp); | |
241 | frp = nextframe(frp); | |
242 | if (frp == nil) { | |
243 | addr = 0; | |
244 | } else { | |
245 | addr = frp->save_pc; | |
246 | } | |
247 | return addr; | |
248 | } | |
249 | ||
250 | /* | |
251 | * Push the value associated with the current function. | |
252 | */ | |
253 | ||
254 | public pushretval(len, isindirect) | |
255 | Integer len; | |
256 | Boolean isindirect; | |
257 | { | |
258 | Word r0; | |
259 | ||
260 | r0 = reg(0); | |
261 | if (isindirect) { | |
262 | rpush((Address) r0, len); | |
263 | } else { | |
264 | switch (len) { | |
265 | case sizeof(char): | |
266 | push(char, r0); | |
267 | break; | |
268 | ||
269 | case sizeof(short): | |
270 | push(short, r0); | |
271 | break; | |
272 | ||
273 | default: | |
274 | if (len == sizeof(Word)) { | |
275 | push(Word, r0); | |
276 | } else if (len == 2*sizeof(Word)) { | |
277 | push(Word, r0); | |
278 | push(Word, reg(1)); | |
279 | } else { | |
280 | panic("not indirect in pushretval?"); | |
281 | } | |
282 | break; | |
283 | } | |
284 | } | |
285 | } | |
286 | ||
287 | /* | |
288 | * Return the base address for locals in the given frame. | |
289 | */ | |
290 | ||
291 | public Address locals_base(frp) | |
292 | register Frame frp; | |
293 | { | |
294 | return (frp == nil) ? reg(FRP) : frp->save_fp; | |
295 | } | |
296 | ||
297 | /* | |
298 | * Return the base address for arguments in the given frame. | |
299 | */ | |
300 | ||
301 | public Address args_base(frp) | |
302 | register Frame frp; | |
303 | { | |
304 | return (frp == nil) ? reg(ARGP) : frp->save_ap; | |
305 | } | |
306 | ||
307 | /* | |
308 | * Return saved register n from the given frame. | |
309 | */ | |
310 | ||
311 | public Word savereg(n, frp) | |
312 | register Integer n; | |
313 | register Frame frp; | |
314 | { | |
315 | register Word w; | |
316 | ||
317 | if (frp == nil) { | |
318 | w = reg(n); | |
319 | } else { | |
320 | switch (n) { | |
321 | case ARGP: | |
322 | w = frp->save_ap; | |
323 | break; | |
324 | ||
325 | case FRP: | |
326 | w = frp->save_fp; | |
327 | break; | |
328 | ||
329 | case STKP: | |
330 | w = reg(STKP); | |
331 | break; | |
332 | ||
333 | case PROGCTR: | |
334 | w = frp->save_pc; | |
335 | break; | |
336 | ||
337 | default: | |
338 | assert(n >= 0 and n < NSAVEREG); | |
339 | w = frp->save_reg[n]; | |
340 | break; | |
341 | } | |
342 | } | |
343 | return w; | |
344 | } | |
345 | ||
346 | /* | |
347 | * Return the nth argument to the current procedure. | |
348 | */ | |
349 | ||
350 | public Word argn(n, frp) | |
351 | Integer n; | |
352 | Frame frp; | |
353 | { | |
354 | Word w; | |
355 | ||
356 | dread(&w, args_base(frp) + (n * sizeof(Word)), sizeof(w)); | |
357 | return w; | |
358 | } | |
359 | ||
360 | /* | |
361 | * Calculate the entry address for a procedure or function parameter, | |
362 | * given the address of the descriptor. | |
363 | */ | |
364 | ||
365 | public Address fparamaddr(a) | |
366 | Address a; | |
367 | { | |
368 | Address r; | |
369 | ||
370 | dread(&r, a, sizeof(r)); | |
371 | return r; | |
372 | } | |
373 | ||
374 | /* | |
375 | * Print a list of currently active blocks starting with most recent. | |
376 | */ | |
377 | ||
378 | public wherecmd() | |
379 | { | |
380 | walkstack(false); | |
381 | } | |
382 | ||
383 | /* | |
384 | * Dump the world to the given file. | |
385 | * Like "where", but variables are dumped also. | |
386 | */ | |
387 | ||
388 | public dump() | |
389 | { | |
390 | walkstack(true); | |
391 | } | |
392 | ||
393 | /* | |
394 | * Walk the stack of active procedures printing information | |
395 | * about each active procedure. | |
396 | */ | |
397 | ||
52646e6f ML |
398 | private walkstack(dumpvariables) |
399 | Boolean dumpvariables; | |
400 | { | |
401 | register Frame frp; | |
52646e6f ML |
402 | register Boolean save; |
403 | register Lineno line; | |
2fd0f574 | 404 | Symbol f; |
52646e6f ML |
405 | struct Frame frame; |
406 | ||
407 | if (notstarted(process)) { | |
408 | error("program is not active"); | |
409 | } else { | |
410 | save = walkingstack; | |
411 | walkingstack = true; | |
412 | frp = &frame; | |
2fd0f574 | 413 | getcurfunc(frp, &f); |
52646e6f ML |
414 | do { |
415 | printf("%s", symname(f)); | |
92167553 ML |
416 | if (not isinline(f)) { |
417 | printparams(f, frp); | |
418 | } | |
91df78fa | 419 | line = srcline(frp->save_pc - 1); |
52646e6f ML |
420 | if (line != 0) { |
421 | printf(", line %d", line); | |
91df78fa | 422 | printf(" in \"%s\"\n", srcfilename(frp->save_pc - 1)); |
52646e6f ML |
423 | } else { |
424 | printf(" at 0x%x\n", frp->save_pc); | |
425 | } | |
426 | if (dumpvariables) { | |
427 | dumpvars(f, frp); | |
428 | putchar('\n'); | |
429 | } | |
2fd0f574 | 430 | frp = nextfunc(frp, &f); |
4fd956ac | 431 | } while (frp != nil and f != program); |
52646e6f ML |
432 | if (dumpvariables) { |
433 | printf("in \"%s\":\n", symname(program)); | |
434 | dumpvars(program, nil); | |
435 | putchar('\n'); | |
436 | } | |
437 | walkingstack = save; | |
438 | } | |
439 | } | |
440 | ||
2fd0f574 SL |
441 | /* |
442 | * Set the current function to the given symbol. | |
443 | * We must adjust "curframe" so that subsequent operations are | |
444 | * not confused; for simplicity we simply clear it. | |
445 | */ | |
446 | ||
447 | public setcurfunc (f) | |
448 | Symbol f; | |
449 | { | |
450 | curfunc = f; | |
451 | curframe = nil; | |
452 | } | |
453 | ||
454 | /* | |
455 | * Set curfunc to be N up/down the stack from its current value. | |
456 | */ | |
457 | ||
458 | public up (n) | |
459 | integer n; | |
460 | { | |
461 | integer i; | |
462 | Symbol f; | |
463 | Frame frp; | |
464 | boolean done; | |
465 | ||
466 | if (not isactive(program)) { | |
467 | error("program is not active"); | |
468 | } else if (curfunc == nil) { | |
469 | error("no current function"); | |
470 | } else { | |
471 | i = 0; | |
472 | f = curfunc; | |
473 | if (curframe != nil) { | |
474 | frp = curframe; | |
475 | } else { | |
476 | frp = findframe(f); | |
477 | } | |
478 | done = false; | |
479 | do { | |
480 | if (frp == nil) { | |
481 | done = true; | |
482 | error("not that many levels"); | |
483 | } else if (i >= n) { | |
484 | done = true; | |
485 | curfunc = f; | |
486 | curframe = &curframerec; | |
487 | *curframe = *frp; | |
488 | } else if (f == program) { | |
489 | done = true; | |
490 | error("not that many levels"); | |
491 | } else { | |
492 | frp = nextfunc(frp, &f); | |
493 | } | |
494 | ++i; | |
495 | } while (not done); | |
496 | } | |
497 | } | |
498 | ||
499 | public down (n) | |
500 | integer n; | |
501 | { | |
502 | integer i, depth; | |
503 | register Frame frp; | |
504 | Symbol f; | |
505 | struct Frame frame; | |
506 | ||
507 | if (not isactive(program)) { | |
508 | error("program is not active"); | |
509 | } else if (curfunc == nil) { | |
510 | error("no current function"); | |
511 | } else { | |
512 | depth = 0; | |
513 | frp = &frame; | |
514 | getcurfunc(frp, &f); | |
515 | if (curframe == nil) { | |
516 | curframe = &curframerec; | |
517 | *curframe = *(findframe(curfunc)); | |
518 | } | |
519 | while ((f != curfunc or !frameeq(frp, curframe)) and f != nil) { | |
520 | frp = nextfunc(frp, &f); | |
521 | ++depth; | |
522 | } | |
523 | if (f == nil or n > depth) { | |
524 | error("not that many levels"); | |
525 | } else { | |
526 | depth -= n; | |
527 | frp = &frame; | |
528 | getcurfunc(frp, &f); | |
529 | for (i = 0; i < depth; i++) { | |
530 | frp = nextfunc(frp, &f); | |
531 | assert(frp != nil); | |
532 | } | |
533 | curfunc = f; | |
534 | *curframe = *frp; | |
535 | } | |
536 | } | |
537 | } | |
538 | ||
52646e6f ML |
539 | /* |
540 | * Find the entry point of a procedure or function. | |
541 | */ | |
542 | ||
543 | public findbeginning(f) | |
544 | Symbol f; | |
545 | { | |
2fd0f574 SL |
546 | if (isinternal(f)) { |
547 | f->symvalue.funcv.beginaddr += 15; | |
548 | } else { | |
549 | f->symvalue.funcv.beginaddr += 2; | |
550 | } | |
52646e6f ML |
551 | } |
552 | ||
553 | /* | |
554 | * Return the address corresponding to the first line in a function. | |
555 | */ | |
556 | ||
557 | public Address firstline(f) | |
558 | Symbol f; | |
559 | { | |
560 | Address addr; | |
561 | ||
562 | addr = codeloc(f); | |
563 | while (linelookup(addr) == 0 and addr < objsize) { | |
564 | ++addr; | |
565 | } | |
566 | if (addr == objsize) { | |
567 | addr = -1; | |
568 | } | |
569 | return addr; | |
570 | } | |
571 | ||
572 | /* | |
573 | * Catcher drops strike three ... | |
574 | */ | |
575 | ||
576 | public runtofirst() | |
577 | { | |
578 | Address addr; | |
579 | ||
580 | addr = pc; | |
581 | while (linelookup(addr) == 0 and addr < objsize) { | |
582 | ++addr; | |
583 | } | |
584 | if (addr < objsize) { | |
585 | stepto(addr); | |
586 | } | |
587 | } | |
588 | ||
589 | /* | |
590 | * Return the address corresponding to the end of the program. | |
591 | * | |
592 | * We look for the entry to "exit". | |
593 | */ | |
594 | ||
595 | public Address lastaddr() | |
596 | { | |
597 | register Symbol s; | |
598 | ||
599 | s = lookup(identname("exit", true)); | |
600 | if (s == nil) { | |
601 | panic("can't find exit"); | |
602 | } | |
603 | return codeloc(s); | |
604 | } | |
605 | ||
606 | /* | |
607 | * Decide if the given function is currently active. | |
608 | * | |
609 | * We avoid calls to "findframe" during a stack trace for efficiency. | |
610 | * Presumably information evaluated while walking the stack is active. | |
611 | */ | |
612 | ||
613 | public Boolean isactive(f) | |
614 | Symbol f; | |
615 | { | |
616 | register Boolean b; | |
617 | ||
618 | if (isfinished(process)) { | |
619 | b = false; | |
620 | } else { | |
621 | if (walkingstack or f == program or | |
622 | (ismodule(f) and isactive(container(f)))) { | |
623 | b = true; | |
624 | } else { | |
625 | b = (Boolean) (findframe(f) != nil); | |
626 | } | |
627 | } | |
628 | return b; | |
629 | } | |
630 | ||
631 | /* | |
632 | * Evaluate a call to a procedure. | |
633 | */ | |
634 | ||
635 | public callproc(procnode, arglist) | |
636 | Node procnode; | |
637 | Node arglist; | |
638 | { | |
639 | Symbol proc; | |
640 | Integer argc; | |
641 | ||
642 | if (procnode->op != O_SYM) { | |
643 | beginerrmsg(); | |
644 | fprintf(stderr, "can't call \""); | |
645 | prtree(stderr, procnode); | |
646 | fprintf(stderr, "\""); | |
647 | enderrmsg(); | |
648 | } | |
649 | assert(procnode->op == O_SYM); | |
650 | proc = procnode->value.sym; | |
651 | if (not isblock(proc)) { | |
652 | error("\"%s\" is not a procedure or function", symname(proc)); | |
653 | } | |
654 | pushenv(); | |
655 | pc = codeloc(proc); | |
656 | argc = pushargs(proc, arglist); | |
657 | beginproc(proc, argc); | |
658 | isstopped = true; | |
659 | event_once(build(O_EQ, build(O_SYM, pcsym), build(O_SYM, retaddrsym)), | |
660 | buildcmdlist(build(O_PROCRTN, proc))); | |
2fd0f574 | 661 | cont(0); |
52646e6f ML |
662 | /* NOTREACHED */ |
663 | } | |
664 | ||
665 | /* | |
666 | * Push the arguments on the process' stack. We do this by first | |
667 | * evaluating them on the "eval" stack, then copying into the process' | |
668 | * space. | |
669 | */ | |
670 | ||
671 | private Integer pushargs(proc, arglist) | |
672 | Symbol proc; | |
673 | Node arglist; | |
674 | { | |
675 | Stack *savesp; | |
676 | int argc, args_size; | |
677 | ||
678 | savesp = sp; | |
679 | argc = evalargs(proc, arglist); | |
680 | args_size = sp - savesp; | |
681 | setreg(STKP, reg(STKP) - args_size); | |
682 | dwrite(savesp, reg(STKP), args_size); | |
683 | sp = savesp; | |
684 | return argc; | |
685 | } | |
686 | ||
687 | /* | |
2fd0f574 SL |
688 | * Check to see if an expression is correct for a given parameter. |
689 | * If the given parameter is false, don't worry about type inconsistencies. | |
690 | * | |
691 | * Return whether or not it is ok. | |
692 | */ | |
693 | ||
694 | private boolean chkparam (actual, formal, chk) | |
695 | Node actual; | |
696 | Symbol formal; | |
697 | boolean chk; | |
698 | { | |
699 | boolean b; | |
700 | ||
701 | b = true; | |
702 | if (chk) { | |
703 | if (formal == nil) { | |
704 | beginerrmsg(); | |
705 | fprintf(stderr, "too many parameters"); | |
706 | b = false; | |
707 | } else if (not compatible(formal->type, actual->nodetype)) { | |
708 | beginerrmsg(); | |
709 | fprintf(stderr, "type mismatch for %s", symname(formal)); | |
710 | b = false; | |
711 | } | |
712 | } | |
713 | if (b and formal != nil and isvarparam(formal) and | |
714 | not isopenarray(formal->type) and actual->op != O_RVAL) | |
715 | { | |
716 | beginerrmsg(); | |
717 | fprintf(stderr, "expected variable, found \""); | |
718 | prtree(stderr, actual); | |
719 | fprintf(stderr, "\""); | |
720 | b = false; | |
721 | } | |
722 | return b; | |
723 | } | |
724 | ||
725 | /* | |
726 | * Pass an expression to a particular parameter. | |
727 | * | |
728 | * Normally we pass either the address or value, but in some cases | |
729 | * (such as C strings) we want to copy the value onto the stack and | |
730 | * pass its address. | |
731 | */ | |
732 | ||
733 | private passparam (actual, formal) | |
734 | Node actual; | |
735 | Symbol formal; | |
736 | { | |
737 | boolean b; | |
738 | Address addr; | |
739 | Stack *savesp; | |
740 | integer paramsize; | |
741 | ||
742 | if (isvarparam(formal) and not isopenarray(formal->type)) { | |
743 | addr = lval(actual->value.arg[0]); | |
744 | push(Address, addr); | |
745 | } else if (passaddr(formal, actual->nodetype)) { | |
746 | savesp = sp; | |
747 | eval(actual); | |
748 | paramsize = sp - savesp; | |
749 | setreg(STKP, reg(STKP) - paramsize); | |
750 | dwrite(savesp, reg(STKP), paramsize); | |
751 | sp = savesp; | |
752 | push(Address, reg(STKP)); | |
753 | if (formal != nil and isopenarray(formal->type)) { | |
754 | push(integer, paramsize div size(formal->type->type)); | |
755 | } | |
756 | } else { | |
757 | eval(actual); | |
758 | } | |
759 | } | |
760 | ||
761 | /* | |
762 | * Evaluate an argument list left-to-right. | |
52646e6f ML |
763 | */ |
764 | ||
765 | private Integer evalargs(proc, arglist) | |
766 | Symbol proc; | |
767 | Node arglist; | |
768 | { | |
2fd0f574 SL |
769 | Node p, actual; |
770 | Symbol formal; | |
52646e6f | 771 | Stack *savesp; |
52646e6f | 772 | Integer count; |
2fd0f574 | 773 | boolean chk; |
52646e6f ML |
774 | |
775 | savesp = sp; | |
776 | count = 0; | |
2fd0f574 SL |
777 | formal = proc->chain; |
778 | chk = (boolean) (not nosource(proc)); | |
52646e6f | 779 | for (p = arglist; p != nil; p = p->value.arg[1]) { |
2fd0f574 SL |
780 | assert(p->op == O_COMMA); |
781 | actual = p->value.arg[0]; | |
782 | if (not chkparam(actual, formal, chk)) { | |
783 | fprintf(stderr, " in call to %s", symname(proc)); | |
52646e6f | 784 | sp = savesp; |
2fd0f574 | 785 | enderrmsg(); |
52646e6f | 786 | } |
2fd0f574 SL |
787 | passparam(actual, formal); |
788 | if (formal != nil) { | |
789 | formal = formal->chain; | |
52646e6f | 790 | } |
52646e6f ML |
791 | ++count; |
792 | } | |
2fd0f574 SL |
793 | if (chk) { |
794 | if (formal != nil) { | |
795 | sp = savesp; | |
796 | error("not enough parameters to %s", symname(proc)); | |
797 | } | |
52646e6f ML |
798 | } |
799 | return count; | |
800 | } | |
801 | ||
802 | public procreturn(f) | |
803 | Symbol f; | |
804 | { | |
805 | flushoutput(); | |
806 | putchar('\n'); | |
807 | printname(stdout, f); | |
808 | printf(" returns successfully\n", symname(f)); | |
809 | popenv(); | |
810 | erecover(); | |
811 | } | |
812 | ||
813 | /* | |
814 | * Push the current environment. | |
815 | */ | |
816 | ||
817 | private pushenv() | |
818 | { | |
819 | push(Address, pc); | |
820 | push(Lineno, curline); | |
821 | push(String, cursource); | |
822 | push(Boolean, isstopped); | |
823 | push(Symbol, curfunc); | |
2fd0f574 SL |
824 | push(Frame, curframe); |
825 | push(struct Frame, curframerec); | |
52646e6f ML |
826 | push(Word, reg(PROGCTR)); |
827 | push(Word, reg(STKP)); | |
828 | } | |
829 | ||
830 | /* | |
831 | * Pop back to the real world. | |
832 | */ | |
833 | ||
834 | public popenv() | |
835 | { | |
836 | register String filename; | |
837 | ||
838 | setreg(STKP, pop(Word)); | |
839 | setreg(PROGCTR, pop(Word)); | |
2fd0f574 SL |
840 | curframerec = pop(struct Frame); |
841 | curframe = pop(Frame); | |
52646e6f ML |
842 | curfunc = pop(Symbol); |
843 | isstopped = pop(Boolean); | |
844 | filename = pop(String); | |
845 | curline = pop(Lineno); | |
846 | pc = pop(Address); | |
847 | setsource(filename); | |
848 | } | |
849 | ||
850 | /* | |
851 | * Flush the debuggee's standard output. | |
852 | * | |
853 | * This is VERY dependent on the use of stdio. | |
854 | */ | |
855 | ||
856 | public flushoutput() | |
857 | { | |
858 | register Symbol p, iob; | |
859 | register Stack *savesp; | |
860 | ||
861 | p = lookup(identname("fflush", true)); | |
862 | while (p != nil and not isblock(p)) { | |
863 | p = p->next_sym; | |
864 | } | |
865 | if (p != nil) { | |
866 | iob = lookup(identname("_iob", true)); | |
867 | if (iob != nil) { | |
868 | pushenv(); | |
869 | pc = codeloc(p); | |
870 | savesp = sp; | |
871 | push(long, address(iob, nil) + sizeof(struct _iobuf)); | |
872 | setreg(STKP, reg(STKP) - sizeof(long)); | |
873 | dwrite(savesp, reg(STKP), sizeof(long)); | |
874 | sp = savesp; | |
875 | beginproc(p, 1); | |
876 | stepto(return_addr()); | |
877 | popenv(); | |
878 | } | |
879 | } | |
880 | } |