2 * Copyright 1988, 1989 Hans-J. Boehm, Alan J. Demers
3 * Copyright (c) 1991-1995 by Xerox Corporation. All rights reserved.
4 * Copyright (c) 1997 by Silicon Graphics. All rights reserved.
5 * Copyright (c) 1999 by Hewlett-Packard Company. All rights reserved.
7 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
8 * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
10 * Permission is hereby granted to use or copy this program
11 * for any purpose, provided the above notices are retained on all copies.
12 * Permission to modify the code and to distribute modified code is granted,
13 * provided the above notices are retained, and a notice that the code was
14 * modified is included with the above copyright notice.
19 void GC_default_print_heap_obj_proc();
20 GC_API void GC_register_finalizer_no_order
21 GC_PROTO((GC_PTR obj, GC_finalization_proc fn, GC_PTR cd,
22 GC_finalization_proc *ofn, GC_PTR *ocd));
25 /* Check whether object with base pointer p has debugging info */
26 /* p is assumed to point to a legitimate object in our part */
28 GC_bool GC_has_debug_info(p)
31 register oh * ohdr = (oh *)p;
32 register ptr_t body = (ptr_t)(ohdr + 1);
33 register word sz = GC_size((ptr_t) ohdr);
35 if (HBLKPTR((ptr_t)ohdr) != HBLKPTR((ptr_t)body)
36 || sz < sizeof (oh)) {
39 if (ohdr -> oh_sz == sz) {
40 /* Object may have had debug info, but has been deallocated */
43 if (ohdr -> oh_sf == (START_FLAG ^ (word)body)) return(TRUE);
44 if (((word *)ohdr)[BYTES_TO_WORDS(sz)-1] == (END_FLAG ^ (word)body)) {
51 /* Store back pointer to source in dest, if that appears to be possible. */
52 /* This is not completely safe, since we may mistakenly conclude that */
53 /* dest has a debugging wrapper. But the error probability is very */
54 /* small, and this shouldn't be used in production code. */
55 /* We assume that dest is the real base pointer. Source will usually */
56 /* be a pointer to the interior of an object. */
57 void GC_store_back_pointer(ptr_t source, ptr_t dest)
59 if (GC_has_debug_info(dest)) {
60 ((oh *)dest) -> oh_back_ptr = (ptr_t)HIDE_POINTER(source);
64 void GC_marked_for_finalization(ptr_t dest) {
65 GC_store_back_pointer(MARKED_FOR_FINALIZATION, dest);
68 /* Store information about the object referencing dest in *base_p */
70 /* source is root ==> *base_p = address, *offset_p = 0 */
71 /* source is heap object ==> *base_p != 0, *offset_p = offset */
72 /* Returns 1 on success, 0 if source couldn't be determined. */
73 /* Dest can be any address within a heap object. */
74 GC_ref_kind GC_get_back_ptr_info(void *dest, void **base_p, size_t *offset_p)
76 oh * hdr = (oh *)GC_base(dest);
79 if (!GC_has_debug_info((ptr_t) hdr)) return GC_NO_SPACE;
80 bp = hdr -> oh_back_ptr;
81 if (MARKED_FOR_FINALIZATION == bp) return GC_FINALIZER_REFD;
82 if (MARKED_FROM_REGISTER == bp) return GC_REFD_FROM_REG;
83 if (0 == bp) return GC_UNREFERENCED;
84 bp = REVEAL_POINTER(bp);
85 bp_base = GC_base(bp);
89 return GC_REFD_FROM_ROOT;
91 if (GC_has_debug_info(bp_base)) bp_base += sizeof(oh);
93 *offset_p = bp - bp_base;
94 return GC_REFD_FROM_HEAP;
98 /* Generate a random heap address. */
99 /* The resulting address is in the heap, but */
100 /* not necessarily inside a valid object. */
101 void *GC_generate_random_heap_address(void)
104 int heap_offset = random() % GC_heapsize;
105 for (i = 0; i < GC_n_heap_sects; ++ i) {
106 int size = GC_heap_sects[i].hs_bytes;
107 if (heap_offset < size) {
108 return GC_heap_sects[i].hs_start + heap_offset;
113 ABORT("GC_generate_random_heap_address: size inconsistency");
118 /* Generate a random address inside a valid marked heap object. */
119 void *GC_generate_random_valid_address(void)
124 result = GC_generate_random_heap_address();
125 base = GC_base(result);
126 if (0 == base) continue;
127 if (!GC_is_marked(base)) continue;
132 /* Print back trace for p */
133 void GC_print_backtrace(void *p)
141 GC_print_heap_obj(GC_base(current));
142 GC_err_printf0("\n");
144 source = GC_get_back_ptr_info(current, &base, &offset);
145 if (GC_UNREFERENCED == source) {
146 GC_err_printf0("Reference could not be found\n");
149 if (GC_NO_SPACE == source) {
150 GC_err_printf0("No debug info in object: Can't find reference\n");
153 GC_err_printf1("Reachable via %d levels of pointers from ",
156 case GC_REFD_FROM_ROOT:
157 GC_err_printf1("root at 0x%lx\n", (unsigned long)base);
159 case GC_REFD_FROM_REG:
160 GC_err_printf0("root in register\n");
162 case GC_FINALIZER_REFD:
163 GC_err_printf0("list of finalizable objects\n");
165 case GC_REFD_FROM_HEAP:
166 GC_err_printf1("offset %ld in object:\n", (unsigned long)offset);
167 /* Take GC_base(base) to get real base, i.e. header. */
168 GC_print_heap_obj(GC_base(base));
169 GC_err_printf0("\n");
177 /* Force a garbage collection and generate a backtrace from a */
178 /* random heap address. */
179 void GC_generate_random_backtrace(void)
183 current = GC_generate_random_valid_address();
184 GC_printf1("Chose address 0x%lx in object\n", (unsigned long)current);
185 GC_print_backtrace(current);
188 #endif /* KEEP_BACK_PTRS */
190 /* Store debugging info into p. Return displaced pointer. */
191 /* Assumes we don't hold allocation lock. */
192 ptr_t GC_store_debug_info(p, sz, string, integer)
193 register ptr_t p; /* base pointer */
198 register word * result = (word *)((oh *)p + 1);
201 /* There is some argument that we should dissble signals here. */
202 /* But that's expensive. And this way things should only appear */
203 /* inconsistent while we're in the handler. */
205 # ifdef KEEP_BACK_PTRS
206 ((oh *)p) -> oh_back_ptr = 0;
208 ((oh *)p) -> oh_string = string;
209 ((oh *)p) -> oh_int = integer;
210 ((oh *)p) -> oh_sz = sz;
211 ((oh *)p) -> oh_sf = START_FLAG ^ (word)result;
212 ((word *)p)[BYTES_TO_WORDS(GC_size(p))-1] =
213 result[ROUNDED_UP_WORDS(sz)] = END_FLAG ^ (word)result;
215 return((ptr_t)result);
218 /* Check the object with debugging info at ohdr */
219 /* return NIL if it's OK. Else return clobbered */
221 ptr_t GC_check_annotated_obj(ohdr)
224 register ptr_t body = (ptr_t)(ohdr + 1);
225 register word gc_sz = GC_size((ptr_t)ohdr);
226 if (ohdr -> oh_sz + DEBUG_BYTES > gc_sz) {
227 return((ptr_t)(&(ohdr -> oh_sz)));
229 if (ohdr -> oh_sf != (START_FLAG ^ (word)body)) {
230 return((ptr_t)(&(ohdr -> oh_sf)));
232 if (((word *)ohdr)[BYTES_TO_WORDS(gc_sz)-1] != (END_FLAG ^ (word)body)) {
233 return((ptr_t)((word *)ohdr + BYTES_TO_WORDS(gc_sz)-1));
235 if (((word *)body)[ROUNDED_UP_WORDS(ohdr -> oh_sz)]
236 != (END_FLAG ^ (word)body)) {
237 return((ptr_t)((word *)body + ROUNDED_UP_WORDS(ohdr -> oh_sz)));
245 register oh * ohdr = (oh *)GC_base(p);
247 GC_err_printf1("0x%lx (", ((unsigned long)ohdr + sizeof(oh)));
248 GC_err_puts(ohdr -> oh_string);
249 GC_err_printf2(":%ld, sz=%ld)\n", (unsigned long)(ohdr -> oh_int),
250 (unsigned long)(ohdr -> oh_sz));
251 PRINT_CALL_CHAIN(ohdr);
254 void GC_debug_print_heap_obj_proc(p)
257 if (GC_has_debug_info(p)) {
260 GC_default_print_heap_obj_proc(p);
264 void GC_print_smashed_obj(p, clobbered_addr)
265 ptr_t p, clobbered_addr;
267 register oh * ohdr = (oh *)GC_base(p);
269 GC_err_printf2("0x%lx in object at 0x%lx(", (unsigned long)clobbered_addr,
271 if (clobbered_addr <= (ptr_t)(&(ohdr -> oh_sz))
272 || ohdr -> oh_string == 0) {
273 GC_err_printf1("<smashed>, appr. sz = %ld)\n",
274 (GC_size((ptr_t)ohdr) - DEBUG_BYTES));
276 if (ohdr -> oh_string[0] == '\0') {
277 GC_err_puts("EMPTY(smashed?)");
279 GC_err_puts(ohdr -> oh_string);
281 GC_err_printf2(":%ld, sz=%ld)\n", (unsigned long)(ohdr -> oh_int),
282 (unsigned long)(ohdr -> oh_sz));
283 PRINT_CALL_CHAIN(ohdr);
287 void GC_check_heap_proc();
289 void GC_start_debugging()
291 GC_check_heap = GC_check_heap_proc;
292 GC_print_heap_obj = GC_debug_print_heap_obj_proc;
293 GC_debugging_started = TRUE;
294 GC_register_displacement((word)sizeof(oh));
297 # if defined(__STDC__) || defined(__cplusplus)
298 void GC_debug_register_displacement(GC_word offset)
300 void GC_debug_register_displacement(offset)
304 GC_register_displacement(offset);
305 GC_register_displacement((word)sizeof(oh) + offset);
309 GC_PTR GC_debug_malloc(size_t lb, GC_EXTRA_PARAMS)
311 GC_PTR GC_debug_malloc(lb, s, i)
315 # ifdef GC_ADD_CALLER
316 --> GC_ADD_CALLER not implemented for K&R C
320 GC_PTR result = GC_malloc(lb + DEBUG_BYTES);
323 GC_err_printf1("GC_debug_malloc(%ld) returning NIL (",
326 GC_err_printf1(":%ld)\n", (unsigned long)i);
329 if (!GC_debugging_started) {
330 GC_start_debugging();
332 ADD_CALL_CHAIN(result, ra);
333 return (GC_store_debug_info(result, (word)lb, s, (word)i));
337 GC_PTR GC_debug_generic_malloc(size_t lb, int k, GC_EXTRA_PARAMS)
339 GC_PTR GC_debug_malloc(lb, k, s, i)
344 # ifdef GC_ADD_CALLER
345 --> GC_ADD_CALLER not implemented for K&R C
349 GC_PTR result = GC_generic_malloc(lb + DEBUG_BYTES, k);
352 GC_err_printf1("GC_debug_malloc(%ld) returning NIL (",
355 GC_err_printf1(":%ld)\n", (unsigned long)i);
358 if (!GC_debugging_started) {
359 GC_start_debugging();
361 ADD_CALL_CHAIN(result, ra);
362 return (GC_store_debug_info(result, (word)lb, s, (word)i));
365 #ifdef STUBBORN_ALLOC
367 GC_PTR GC_debug_malloc_stubborn(size_t lb, GC_EXTRA_PARAMS)
369 GC_PTR GC_debug_malloc_stubborn(lb, s, i)
375 GC_PTR result = GC_malloc_stubborn(lb + DEBUG_BYTES);
378 GC_err_printf1("GC_debug_malloc(%ld) returning NIL (",
381 GC_err_printf1(":%ld)\n", (unsigned long)i);
384 if (!GC_debugging_started) {
385 GC_start_debugging();
387 ADD_CALL_CHAIN(result, ra);
388 return (GC_store_debug_info(result, (word)lb, s, (word)i));
391 void GC_debug_change_stubborn(p)
394 register GC_PTR q = GC_base(p);
398 GC_err_printf1("Bad argument: 0x%lx to GC_debug_change_stubborn\n",
400 ABORT("GC_debug_change_stubborn: bad arg");
403 if (hhdr -> hb_obj_kind != STUBBORN) {
404 GC_err_printf1("GC_debug_change_stubborn arg not stubborn: 0x%lx\n",
406 ABORT("GC_debug_change_stubborn: arg not stubborn");
408 GC_change_stubborn(q);
411 void GC_debug_end_stubborn_change(p)
414 register GC_PTR q = GC_base(p);
418 GC_err_printf1("Bad argument: 0x%lx to GC_debug_end_stubborn_change\n",
420 ABORT("GC_debug_end_stubborn_change: bad arg");
423 if (hhdr -> hb_obj_kind != STUBBORN) {
424 GC_err_printf1("debug_end_stubborn_change arg not stubborn: 0x%lx\n",
426 ABORT("GC_debug_end_stubborn_change: arg not stubborn");
428 GC_end_stubborn_change(q);
431 #endif /* STUBBORN_ALLOC */
434 GC_PTR GC_debug_malloc_atomic(size_t lb, GC_EXTRA_PARAMS)
436 GC_PTR GC_debug_malloc_atomic(lb, s, i)
442 GC_PTR result = GC_malloc_atomic(lb + DEBUG_BYTES);
445 GC_err_printf1("GC_debug_malloc_atomic(%ld) returning NIL (",
448 GC_err_printf1(":%ld)\n", (unsigned long)i);
451 if (!GC_debugging_started) {
452 GC_start_debugging();
454 ADD_CALL_CHAIN(result, ra);
455 return (GC_store_debug_info(result, (word)lb, s, (word)i));
459 GC_PTR GC_debug_malloc_uncollectable(size_t lb, GC_EXTRA_PARAMS)
461 GC_PTR GC_debug_malloc_uncollectable(lb, s, i)
467 GC_PTR result = GC_malloc_uncollectable(lb + DEBUG_BYTES);
470 GC_err_printf1("GC_debug_malloc_uncollectable(%ld) returning NIL (",
473 GC_err_printf1(":%ld)\n", (unsigned long)i);
476 if (!GC_debugging_started) {
477 GC_start_debugging();
479 ADD_CALL_CHAIN(result, ra);
480 return (GC_store_debug_info(result, (word)lb, s, (word)i));
483 #ifdef ATOMIC_UNCOLLECTABLE
485 GC_PTR GC_debug_malloc_atomic_uncollectable(size_t lb, GC_EXTRA_PARAMS)
487 GC_PTR GC_debug_malloc_atomic_uncollectable(lb, s, i)
493 GC_PTR result = GC_malloc_atomic_uncollectable(lb + DEBUG_BYTES);
497 "GC_debug_malloc_atomic_uncollectable(%ld) returning NIL (",
500 GC_err_printf1(":%ld)\n", (unsigned long)i);
503 if (!GC_debugging_started) {
504 GC_start_debugging();
506 ADD_CALL_CHAIN(result, ra);
507 return (GC_store_debug_info(result, (word)lb, s, (word)i));
509 #endif /* ATOMIC_UNCOLLECTABLE */
512 void GC_debug_free(GC_PTR p)
514 void GC_debug_free(p)
518 register GC_PTR base;
519 register ptr_t clobbered;
524 GC_err_printf1("Attempt to free invalid pointer %lx\n",
526 ABORT("free(invalid pointer)");
528 if ((ptr_t)p - (ptr_t)base != sizeof(oh)) {
530 "GC_debug_free called on pointer %lx wo debugging info\n",
533 clobbered = GC_check_annotated_obj((oh *)base);
534 if (clobbered != 0) {
535 if (((oh *)base) -> oh_sz == GC_size(base)) {
537 "GC_debug_free: found previously deallocated (?) object at ");
539 GC_err_printf0("GC_debug_free: found smashed location at ");
541 GC_print_smashed_obj(p, clobbered);
543 /* Invalidate size */
544 ((oh *)base) -> oh_sz = GC_size(base);
549 register hdr * hhdr = HDR(p);
550 GC_bool uncollectable = FALSE;
552 if (hhdr -> hb_obj_kind == UNCOLLECTABLE) {
553 uncollectable = TRUE;
555 # ifdef ATOMIC_UNCOLLECTABLE
556 if (hhdr -> hb_obj_kind == AUNCOLLECTABLE) {
557 uncollectable = TRUE;
560 if (uncollectable) GC_free(base);
561 } /* !GC_find_leak */
565 GC_PTR GC_debug_realloc(GC_PTR p, size_t lb, GC_EXTRA_PARAMS)
567 GC_PTR GC_debug_realloc(p, lb, s, i)
574 register GC_PTR base = GC_base(p);
575 register ptr_t clobbered;
576 register GC_PTR result;
577 register size_t copy_sz = lb;
578 register size_t old_sz;
581 if (p == 0) return(GC_debug_malloc(lb, OPT_RA s, i));
584 "Attempt to reallocate invalid pointer %lx\n", (unsigned long)p);
585 ABORT("realloc(invalid pointer)");
587 if ((ptr_t)p - (ptr_t)base != sizeof(oh)) {
589 "GC_debug_realloc called on pointer %lx wo debugging info\n",
591 return(GC_realloc(p, lb));
594 switch (hhdr -> hb_obj_kind) {
595 # ifdef STUBBORN_ALLOC
597 result = GC_debug_malloc_stubborn(lb, OPT_RA s, i);
601 result = GC_debug_malloc(lb, OPT_RA s, i);
604 result = GC_debug_malloc_atomic(lb, OPT_RA s, i);
607 result = GC_debug_malloc_uncollectable(lb, OPT_RA s, i);
609 # ifdef ATOMIC_UNCOLLECTABLE
611 result = GC_debug_malloc_atomic_uncollectable(lb, OPT_RA s, i);
615 GC_err_printf0("GC_debug_realloc: encountered bad kind\n");
618 clobbered = GC_check_annotated_obj((oh *)base);
619 if (clobbered != 0) {
620 GC_err_printf0("GC_debug_realloc: found smashed location at ");
621 GC_print_smashed_obj(p, clobbered);
623 old_sz = ((oh *)base) -> oh_sz;
624 if (old_sz < copy_sz) copy_sz = old_sz;
625 if (result == 0) return(0);
626 BCOPY(p, result, copy_sz);
631 /* Check all marked objects in the given block for validity */
633 void GC_check_heap_block(hbp, dummy)
634 register struct hblk *hbp; /* ptr to current heap block */
637 register struct hblkhdr * hhdr = HDR(hbp);
638 register word sz = hhdr -> hb_sz;
639 register int word_no;
640 register word *p, *plim;
642 p = (word *)(hbp->hb_body);
647 plim = (word *)((((word)hbp) + HBLKSIZE) - WORDS_TO_BYTES(sz));
649 /* go through all words in block */
651 if( mark_bit_from_hdr(hhdr, word_no)
652 && GC_has_debug_info((ptr_t)p)) {
653 ptr_t clobbered = GC_check_annotated_obj((oh *)p);
655 if (clobbered != 0) {
657 "GC_check_heap_block: found smashed location at ");
658 GC_print_smashed_obj((ptr_t)p, clobbered);
667 /* This assumes that all accessible objects are marked, and that */
668 /* I hold the allocation lock. Normally called by collector. */
669 void GC_check_heap_proc()
671 # ifndef SMALL_CONFIG
672 if (sizeof(oh) & (2 * sizeof(word) - 1) != 0) {
673 ABORT("Alignment problem: object header has inappropriate size\n");
676 GC_apply_to_all_blocks(GC_check_heap_block, (word)0);
680 GC_finalization_proc cl_fn;
685 void * GC_make_closure(GC_finalization_proc fn, void * data)
687 GC_PTR GC_make_closure(fn, data)
688 GC_finalization_proc fn;
692 struct closure * result =
693 (struct closure *) GC_malloc(sizeof (struct closure));
695 result -> cl_fn = fn;
696 result -> cl_data = data;
697 return((GC_PTR)result);
701 void GC_debug_invoke_finalizer(void * obj, void * data)
703 void GC_debug_invoke_finalizer(obj, data)
708 register struct closure * cl = (struct closure *) data;
710 (*(cl -> cl_fn))((GC_PTR)((char *)obj + sizeof(oh)), cl -> cl_data);
715 void GC_debug_register_finalizer(GC_PTR obj, GC_finalization_proc fn,
716 GC_PTR cd, GC_finalization_proc *ofn,
719 void GC_debug_register_finalizer(obj, fn, cd, ofn, ocd)
721 GC_finalization_proc fn;
723 GC_finalization_proc *ofn;
727 ptr_t base = GC_base(obj);
728 if (0 == base || (ptr_t)obj - base != sizeof(oh)) {
730 "GC_register_finalizer called with non-base-pointer 0x%lx\n",
733 GC_register_finalizer(base, GC_debug_invoke_finalizer,
734 GC_make_closure(fn,cd), ofn, ocd);
738 void GC_debug_register_finalizer_no_order
739 (GC_PTR obj, GC_finalization_proc fn,
740 GC_PTR cd, GC_finalization_proc *ofn,
743 void GC_debug_register_finalizer_no_order
744 (obj, fn, cd, ofn, ocd)
746 GC_finalization_proc fn;
748 GC_finalization_proc *ofn;
752 ptr_t base = GC_base(obj);
753 if (0 == base || (ptr_t)obj - base != sizeof(oh)) {
755 "GC_register_finalizer_no_order called with non-base-pointer 0x%lx\n",
758 GC_register_finalizer_no_order(base, GC_debug_invoke_finalizer,
759 GC_make_closure(fn,cd), ofn, ocd);
763 void GC_debug_register_finalizer_ignore_self
764 (GC_PTR obj, GC_finalization_proc fn,
765 GC_PTR cd, GC_finalization_proc *ofn,
768 void GC_debug_register_finalizer_ignore_self
769 (obj, fn, cd, ofn, ocd)
771 GC_finalization_proc fn;
773 GC_finalization_proc *ofn;
777 ptr_t base = GC_base(obj);
778 if (0 == base || (ptr_t)obj - base != sizeof(oh)) {
780 "GC_register_finalizer_ignore_self called with non-base-pointer 0x%lx\n",
783 GC_register_finalizer_ignore_self(base, GC_debug_invoke_finalizer,
784 GC_make_closure(fn,cd), ofn, ocd);