2 * sgen-bridge.c: Simple generational GC.
4 * Copyright 2011 Novell, Inc (http://www.novell.com)
5 * Copyright 2011 Xamarin Inc (http://www.xamarin.com)
7 * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
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13 * provided the above notices are retained, and a notice that the code was
14 * modified is included with the above copyright notice.
17 * Copyright 2001-2003 Ximian, Inc
18 * Copyright 2003-2010 Novell, Inc.
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47 #include "sgen-bridge.h"
48 #include "sgen-hash-table.h"
49 #include "utils/mono-logger-internal.h"
50 #include "utils/mono-time.h"
60 #define DYN_ARRAY_REF(da,i) ((void*)((da)->data + (i) * (da)->elem_size))
61 #define DYN_ARRAY_PTR_REF(da,i) (((void**)(da)->data) [(i)])
62 #define DYN_ARRAY_INT_REF(da,i) (((int*)(da)->data) [(i)])
63 #define DYN_ARRAY_PTR_STATIC_INITIALIZER { 0, sizeof (void*), 0, NULL }
64 #define DYN_ARRAY_INT_STATIC_INITIALIZER { 0, sizeof (int), 0, NULL }
67 dyn_array_init (DynArray *da, int elem_size)
70 da->elem_size = elem_size;
76 dyn_array_ptr_init (DynArray *da)
78 dyn_array_init (da, sizeof (void*));
82 dyn_array_int_init (DynArray *da)
84 dyn_array_init (da, sizeof (int));
88 dyn_array_uninit (DynArray *da)
90 if (da->capacity <= 0)
93 sgen_free_internal_dynamic (da->data, da->elem_size * da->capacity, INTERNAL_MEM_BRIDGE_DATA);
98 dyn_array_ensure_capacity (DynArray *da, int capacity)
100 int old_capacity = da->capacity;
103 if (capacity <= old_capacity)
106 if (da->capacity == 0)
108 while (capacity > da->capacity)
111 new_data = sgen_alloc_internal_dynamic (da->elem_size * da->capacity, INTERNAL_MEM_BRIDGE_DATA, TRUE);
112 memcpy (new_data, da->data, da->elem_size * da->size);
113 sgen_free_internal_dynamic (da->data, da->elem_size * old_capacity, INTERNAL_MEM_BRIDGE_DATA);
118 dyn_array_add (DynArray *da)
122 dyn_array_ensure_capacity (da, da->size + 1);
124 p = DYN_ARRAY_REF (da, da->size);
130 dyn_array_ptr_add (DynArray *da, void *ptr)
132 void **p = dyn_array_add (da);
136 #define dyn_array_ptr_push dyn_array_ptr_add
139 dyn_array_ptr_pop (DynArray *da)
142 g_assert (da->size > 0);
143 p = DYN_ARRAY_PTR_REF (da, da->size - 1);
149 dyn_array_int_add (DynArray *da, int x)
151 int *p = dyn_array_add (da);
157 dyn_array_ptr_contains (DynArray *da, void *ptr)
160 for (i = 0; i < da->size; ++i)
161 if (DYN_ARRAY_PTR_REF (da, i) == ptr)
168 dyn_array_int_contains (DynArray *da, int x)
171 for (i = 0; i < da->size; ++i)
172 if (DYN_ARRAY_INT_REF (da, i) == x)
177 static DynArray merge_array;
180 dyn_array_int_merge (DynArray *dst, DynArray *src)
184 dyn_array_ensure_capacity (&merge_array, dst->size + src->size);
185 merge_array.size = 0;
187 for (i = j = 0; i < dst->size || j < src->size; ) {
188 if (i < dst->size && j < src->size) {
189 int a = DYN_ARRAY_INT_REF (dst, i);
190 int b = DYN_ARRAY_INT_REF (src, j);
192 dyn_array_int_add (&merge_array, a);
195 dyn_array_int_add (&merge_array, a);
199 dyn_array_int_add (&merge_array, b);
202 } else if (i < dst->size) {
203 dyn_array_int_add (&merge_array, DYN_ARRAY_INT_REF (dst, i));
206 dyn_array_int_add (&merge_array, DYN_ARRAY_INT_REF (src, j));
211 if (merge_array.size > dst->size) {
212 dyn_array_ensure_capacity (dst, merge_array.size);
213 memcpy (DYN_ARRAY_REF (dst, 0), DYN_ARRAY_REF (&merge_array, 0), merge_array.size * merge_array.elem_size);
214 dst->size = merge_array.size;
219 dyn_array_int_merge_one (DynArray *array, int value)
223 int end = array->size;
225 for (i = 0; i < end; ++i) {
226 if (DYN_ARRAY_INT_REF (array, i) == value)
228 else if (DYN_ARRAY_INT_REF (array, i) > value)
232 dyn_array_ensure_capacity (array, array->size + 1);
235 tmp = DYN_ARRAY_INT_REF (array, i);
236 for (; i <= end; ++i) {
237 DYN_ARRAY_INT_REF (array, i) = value;
239 tmp = DYN_ARRAY_INT_REF (array, i + 1);
241 DYN_ARRAY_INT_REF (array, end + 1) = tmp;
243 DYN_ARRAY_INT_REF (array, end) = value;
249 * FIXME: Optimizations:
251 * Don't allocate a scrs array for just one source. Most objects have
252 * just one source, so use the srcs pointer itself.
254 typedef struct _HashEntry {
255 MonoObject *obj; /* This is a duplicate - it's already stored in the hash table */
267 typedef struct _SCC {
270 int num_bridge_entries;
271 DynArray xrefs; /* these are incoming, not outgoing */
274 static SgenHashTable hash_table = SGEN_HASH_TABLE_INIT (INTERNAL_MEM_BRIDGE_HASH_TABLE, INTERNAL_MEM_BRIDGE_HASH_TABLE_ENTRY, sizeof (HashEntry), mono_aligned_addr_hash, NULL);
276 static MonoGCBridgeCallbacks bridge_callbacks;
278 static int current_time;
280 gboolean bridge_processing_in_progress = FALSE;
283 mono_gc_wait_for_bridge_processing (void)
285 if (!bridge_processing_in_progress)
288 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "GC_BRIDGE waiting for bridge processing to finish");
295 mono_gc_register_bridge_callbacks (MonoGCBridgeCallbacks *callbacks)
297 if (callbacks->bridge_version != SGEN_BRIDGE_VERSION)
298 g_error ("Invalid bridge callback version. Expected %d but got %d\n", SGEN_BRIDGE_VERSION, callbacks->bridge_version);
300 bridge_callbacks = *callbacks;
304 sgen_is_bridge_object (MonoObject *obj)
306 if ((obj->vtable->gc_bits & SGEN_GC_BIT_BRIDGE_OBJECT) != SGEN_GC_BIT_BRIDGE_OBJECT)
308 return bridge_callbacks.is_bridge_object (obj);
312 sgen_is_bridge_class (MonoClass *class)
314 return bridge_callbacks.is_bridge_class (class);
318 sgen_need_bridge_processing (void)
320 return bridge_callbacks.cross_references != NULL;
324 get_hash_entry (MonoObject *obj, gboolean *existing)
326 HashEntry *entry = sgen_hash_table_lookup (&hash_table, obj);
337 memset (&new_entry, 0, sizeof (HashEntry));
340 dyn_array_ptr_init (&new_entry.srcs);
341 new_entry.finishing_time = -1;
342 new_entry.scc_index = -1;
344 sgen_hash_table_replace (&hash_table, obj, &new_entry, NULL);
346 return sgen_hash_table_lookup (&hash_table, obj);
350 add_source (HashEntry *entry, HashEntry *src)
352 dyn_array_ptr_add (&entry->srcs, src);
363 SGEN_HASH_TABLE_FOREACH (&hash_table, obj, entry) {
364 total_srcs += entry->srcs.size;
365 if (entry->srcs.size > max_srcs)
366 max_srcs = entry->srcs.size;
367 dyn_array_uninit (&entry->srcs);
368 } SGEN_HASH_TABLE_FOREACH_END;
370 sgen_hash_table_clean (&hash_table);
372 dyn_array_uninit (&merge_array);
373 //g_print ("total srcs %d - max %d\n", total_srcs, max_srcs);
377 register_bridge_object (MonoObject *obj)
379 HashEntry *entry = get_hash_entry (obj, NULL);
380 entry->is_bridge = TRUE;
385 register_finishing_time (HashEntry *entry, int t)
387 g_assert (entry->finishing_time < 0);
388 entry->finishing_time = t;
392 object_is_live (MonoObject **objp)
394 MonoObject *obj = *objp;
395 MonoObject *fwd = SGEN_OBJECT_IS_FORWARDED (obj);
398 return sgen_hash_table_lookup (&hash_table, fwd) == NULL;
400 if (!sgen_object_is_live (obj))
402 return sgen_hash_table_lookup (&hash_table, obj) == NULL;
405 static DynArray registered_bridges = DYN_ARRAY_PTR_STATIC_INITIALIZER;
406 static DynArray dfs_stack;
408 static int dsf1_passes, dsf2_passes;
412 #define HANDLE_PTR(ptr,obj) do { \
413 MonoObject *dst = (MonoObject*)*(ptr); \
414 if (dst && !object_is_live (&dst)) { \
415 dyn_array_ptr_push (&dfs_stack, obj_entry); \
416 dyn_array_ptr_push (&dfs_stack, get_hash_entry (dst, NULL)); \
421 dfs1 (HashEntry *obj_entry, HashEntry *src)
423 g_assert (dfs_stack.size == 0);
425 dyn_array_ptr_push (&dfs_stack, src);
426 dyn_array_ptr_push (&dfs_stack, obj_entry);
433 obj_entry = dyn_array_ptr_pop (&dfs_stack);
435 src = dyn_array_ptr_pop (&dfs_stack);
437 obj = obj_entry->obj;
441 //g_print ("link %s -> %s\n", sgen_safe_name (src->obj), sgen_safe_name (obj));
442 add_source (obj_entry, src);
444 //g_print ("starting with %s\n", sgen_safe_name (obj));
447 if (obj_entry->is_visited)
450 obj_entry->is_visited = TRUE;
452 dyn_array_ptr_push (&dfs_stack, obj_entry);
453 /* NULL marks that the next entry is to be finished */
454 dyn_array_ptr_push (&dfs_stack, NULL);
456 #include "sgen-scan-object.h"
458 obj_entry = dyn_array_ptr_pop (&dfs_stack);
460 //g_print ("finish %s\n", sgen_safe_name (obj_entry->obj));
461 register_finishing_time (obj_entry, current_time++);
463 } while (dfs_stack.size > 0);
467 scc_add_xref (SCC *src, SCC *dst)
469 g_assert (src != dst);
470 g_assert (src->index != dst->index);
472 if (dyn_array_int_contains (&dst->xrefs, src->index))
474 if (src->num_bridge_entries) {
475 dyn_array_int_merge_one (&dst->xrefs, src->index);
478 dyn_array_int_merge (&dst->xrefs, &src->xrefs);
479 for (i = 0; i < dst->xrefs.size; ++i)
480 g_assert (DYN_ARRAY_INT_REF (&dst->xrefs, i) != dst->index);
485 scc_add_entry (SCC *scc, HashEntry *entry)
487 g_assert (entry->scc_index < 0);
488 entry->scc_index = scc->index;
489 if (entry->is_bridge)
490 ++scc->num_bridge_entries;
493 static DynArray sccs;
494 static SCC *current_scc;
497 dfs2 (HashEntry *entry)
501 g_assert (dfs_stack.size == 0);
503 dyn_array_ptr_push (&dfs_stack, entry);
506 entry = dyn_array_ptr_pop (&dfs_stack);
509 if (entry->scc_index >= 0) {
510 if (entry->scc_index != current_scc->index)
511 scc_add_xref (DYN_ARRAY_REF (&sccs, entry->scc_index), current_scc);
515 scc_add_entry (current_scc, entry);
517 for (i = 0; i < entry->srcs.size; ++i)
518 dyn_array_ptr_push (&dfs_stack, DYN_ARRAY_PTR_REF (&entry->srcs, i));
519 } while (dfs_stack.size > 0);
523 compare_hash_entries (const void *ep1, const void *ep2)
525 HashEntry *e1 = *(HashEntry**)ep1;
526 HashEntry *e2 = *(HashEntry**)ep2;
527 return e2->finishing_time - e1->finishing_time;
530 static unsigned long step_1, step_2, step_3, step_4, step_5, step_6, step_7, step_8;
531 static int fist_pass_links, second_pass_links, sccs_links;
532 static int max_sccs_links = 0;
535 sgen_bridge_register_finalized_object (MonoObject *obj)
537 g_assert (sgen_need_bridge_processing ());
538 dyn_array_ptr_push (®istered_bridges, obj);
542 sgen_bridge_reset_data (void)
544 registered_bridges.size = 0;
548 sgen_bridge_processing_stw_step (void)
551 SGEN_TV_DECLARE (atv);
552 SGEN_TV_DECLARE (btv);
554 if (!registered_bridges.size)
558 * bridge_processing_in_progress must be set with the world
559 * stopped. If not there would be race conditions.
561 bridge_processing_in_progress = TRUE;
563 SGEN_TV_GETTIME (btv);
567 dyn_array_ptr_init (&dfs_stack);
568 dyn_array_int_init (&merge_array);
572 First we insert all bridges into the hash table and then we do dfs1.
574 It must be done in 2 steps since the bridge arrays doesn't come in reverse topological order,
575 which means that we can have entry N pointing to entry N + 1.
577 If we dfs1 entry N before N + 1 is registered we'll not consider N + 1 for this bridge
578 pass and not create the required xref between the two.
580 for (i = 0; i < registered_bridges.size; ++i)
581 register_bridge_object (DYN_ARRAY_PTR_REF (®istered_bridges, i));
583 for (i = 0; i < registered_bridges.size; ++i)
584 dfs1 (get_hash_entry (DYN_ARRAY_PTR_REF (®istered_bridges, i), NULL), NULL);
586 SGEN_TV_GETTIME (atv);
587 step_2 = SGEN_TV_ELAPSED (btv, atv);
591 is_bridge_object_alive (MonoObject *obj, void *data)
593 SgenHashTable *table = data;
594 unsigned char *value = sgen_hash_table_lookup (table, obj);
601 sgen_bridge_processing_finish (int generation)
604 int num_sccs, num_xrefs;
605 int max_entries, max_xrefs;
606 int hash_table_size, sccs_size;
609 int num_registered_bridges;
610 HashEntry **all_entries;
611 MonoGCBridgeSCC **api_sccs;
612 MonoGCBridgeXRef *api_xrefs;
613 SgenHashTable alive_hash = SGEN_HASH_TABLE_INIT (INTERNAL_MEM_BRIDGE_ALIVE_HASH_TABLE, INTERNAL_MEM_BRIDGE_ALIVE_HASH_TABLE_ENTRY, 1, mono_aligned_addr_hash, NULL);
614 SGEN_TV_DECLARE (atv);
615 SGEN_TV_DECLARE (btv);
617 if (!registered_bridges.size)
620 g_assert (bridge_processing_in_progress);
622 SGEN_TV_GETTIME (atv);
624 /* alloc and fill array of all entries */
626 all_entries = sgen_alloc_internal_dynamic (sizeof (HashEntry*) * hash_table.num_entries, INTERNAL_MEM_BRIDGE_DATA, TRUE);
629 SGEN_HASH_TABLE_FOREACH (&hash_table, obj, entry) {
630 g_assert (entry->finishing_time >= 0);
631 all_entries [j++] = entry;
632 fist_pass_links += entry->srcs.size;
633 } SGEN_HASH_TABLE_FOREACH_END;
634 g_assert (j == hash_table.num_entries);
635 hash_table_size = hash_table.num_entries;
637 /* sort array according to decreasing finishing time */
639 sgen_qsort (all_entries, hash_table.num_entries, sizeof (HashEntry*), compare_hash_entries);
641 SGEN_TV_GETTIME (btv);
642 step_3 = SGEN_TV_ELAPSED (atv, btv);
644 /* second DFS pass */
646 dyn_array_init (&sccs, sizeof (SCC));
647 for (i = 0; i < hash_table.num_entries; ++i) {
648 HashEntry *entry = all_entries [i];
649 if (entry->scc_index < 0) {
650 int index = sccs.size;
651 current_scc = dyn_array_add (&sccs);
652 current_scc->index = index;
653 current_scc->num_bridge_entries = 0;
654 current_scc->api_index = -1;
655 dyn_array_int_init (¤t_scc->xrefs);
661 sccs_size = sccs.size;
663 for (i = 0; i < hash_table.num_entries; ++i) {
664 HashEntry *entry = all_entries [i];
665 second_pass_links += entry->srcs.size;
668 SGEN_TV_GETTIME (atv);
669 step_4 = SGEN_TV_ELAPSED (btv, atv);
671 //g_print ("%d sccs\n", sccs.size);
673 dyn_array_uninit (&dfs_stack);
675 /* init data for callback */
678 for (i = 0; i < sccs.size; ++i) {
679 SCC *scc = DYN_ARRAY_REF (&sccs, i);
680 g_assert (scc->index == i);
681 if (scc->num_bridge_entries)
683 sccs_links += scc->xrefs.size;
684 max_sccs_links = MAX (max_sccs_links, scc->xrefs.size);
687 api_sccs = sgen_alloc_internal_dynamic (sizeof (MonoGCBridgeSCC*) * num_sccs, INTERNAL_MEM_BRIDGE_DATA, TRUE);
690 for (i = 0; i < sccs.size; ++i) {
691 SCC *scc = DYN_ARRAY_REF (&sccs, i);
692 if (!scc->num_bridge_entries)
695 api_sccs [j] = sgen_alloc_internal_dynamic (sizeof (MonoGCBridgeSCC) + sizeof (MonoObject*) * scc->num_bridge_entries, INTERNAL_MEM_BRIDGE_DATA, TRUE);
696 api_sccs [j]->is_alive = FALSE;
697 api_sccs [j]->num_objs = scc->num_bridge_entries;
698 scc->num_bridge_entries = 0;
699 scc->api_index = j++;
701 num_xrefs += scc->xrefs.size;
704 SGEN_HASH_TABLE_FOREACH (&hash_table, obj, entry) {
705 if (entry->is_bridge) {
706 SCC *scc = DYN_ARRAY_REF (&sccs, entry->scc_index);
707 api_sccs [scc->api_index]->objs [scc->num_bridge_entries++] = entry->obj;
709 } SGEN_HASH_TABLE_FOREACH_END;
711 api_xrefs = sgen_alloc_internal_dynamic (sizeof (MonoGCBridgeXRef) * num_xrefs, INTERNAL_MEM_BRIDGE_DATA, TRUE);
713 for (i = 0; i < sccs.size; ++i) {
715 SCC *scc = DYN_ARRAY_REF (&sccs, i);
716 if (!scc->num_bridge_entries)
718 for (k = 0; k < scc->xrefs.size; ++k) {
719 SCC *src_scc = DYN_ARRAY_REF (&sccs, DYN_ARRAY_INT_REF (&scc->xrefs, k));
720 if (!src_scc->num_bridge_entries)
722 api_xrefs [j].src_scc_index = src_scc->api_index;
723 api_xrefs [j].dst_scc_index = scc->api_index;
728 SGEN_TV_GETTIME (btv);
729 step_5 = SGEN_TV_ELAPSED (atv, btv);
734 max_entries = max_xrefs = 0;
735 for (i = 0; i < sccs.size; ++i) {
736 SCC *scc = DYN_ARRAY_REF (&sccs, i);
737 if (scc->num_bridge_entries)
739 if (scc->num_bridge_entries > max_entries)
740 max_entries = scc->num_bridge_entries;
741 if (scc->xrefs.size > max_xrefs)
742 max_xrefs = scc->xrefs.size;
743 dyn_array_uninit (&scc->xrefs);
746 dyn_array_uninit (&sccs);
748 sgen_free_internal_dynamic (all_entries, sizeof (HashEntry*) * hash_table.num_entries, INTERNAL_MEM_BRIDGE_DATA);
751 /* Empty the registered bridges array */
752 num_registered_bridges = registered_bridges.size;
753 registered_bridges.size = 0;
755 SGEN_TV_GETTIME (atv);
756 step_6 = SGEN_TV_ELAPSED (btv, atv);
758 //g_print ("%d sccs containing bridges - %d max bridge objects - %d max xrefs\n", j, max_entries, max_xrefs);
762 bridge_callbacks.cross_references (num_sccs, api_sccs, num_xrefs, api_xrefs);
764 /* Release for finalization those objects we no longer care. */
765 SGEN_TV_GETTIME (btv);
766 step_7 = SGEN_TV_ELAPSED (atv, btv);
768 for (i = 0; i < num_sccs; ++i) {
769 unsigned char alive = api_sccs [i]->is_alive ? 1 : 0;
770 for (j = 0; j < api_sccs [i]->num_objs; ++j) {
771 /* Build hash table for nulling weak links. */
772 sgen_hash_table_replace (&alive_hash, api_sccs [i]->objs [j], &alive, NULL);
774 /* Release for finalization those objects we no longer care. */
775 if (!api_sccs [i]->is_alive)
776 sgen_mark_bridge_object (api_sccs [i]->objs [j]);
780 /* Null weak links to dead objects. */
781 sgen_null_links_with_predicate (GENERATION_NURSERY, is_bridge_object_alive, &alive_hash);
782 if (generation == GENERATION_OLD)
783 sgen_null_links_with_predicate (GENERATION_OLD, is_bridge_object_alive, &alive_hash);
785 sgen_hash_table_clean (&alive_hash);
787 /* free callback data */
789 for (i = 0; i < num_sccs; ++i) {
790 sgen_free_internal_dynamic (api_sccs [i],
791 sizeof (MonoGCBridgeSCC) + sizeof (MonoObject*) * api_sccs [i]->num_objs,
792 INTERNAL_MEM_BRIDGE_DATA);
794 sgen_free_internal_dynamic (api_sccs, sizeof (MonoGCBridgeSCC*) * num_sccs, INTERNAL_MEM_BRIDGE_DATA);
796 sgen_free_internal_dynamic (api_xrefs, sizeof (MonoGCBridgeXRef) * num_xrefs, INTERNAL_MEM_BRIDGE_DATA);
798 SGEN_TV_GETTIME (atv);
799 step_8 = SGEN_TV_ELAPSED (btv, atv);
801 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "GC_BRIDGE num-objects %d num_hash_entries %d sccs size %d init %.2fms df1 %.2fms sort %.2fms dfs2 %.2fms setup-cb %.2fms free-data %.2fms user-cb %.2fms clenanup %.2fms links %d/%d/%d/%d dfs passes %d/%d",
802 num_registered_bridges, hash_table_size, sccs.size,
811 fist_pass_links, second_pass_links, sccs_links, max_sccs_links,
812 dsf1_passes, dsf2_passes);
814 step_1 = 0; /* We must cleanup since this value is used as an accumulator. */
816 bridge_processing_in_progress = FALSE;
820 sgen_bridge_describe_pointer (MonoObject *obj)
825 for (i = 0; i < registered_bridges.size; ++i) {
826 if (obj == DYN_ARRAY_PTR_REF (®istered_bridges, i)) {
827 printf ("Pointer is a registered bridge object.\n");
832 entry = sgen_hash_table_lookup (&hash_table, obj);
836 printf ("Bridge hash table entry %p:\n", entry);
837 printf (" is bridge: %d\n", (int)entry->is_bridge);
838 printf (" is visited: %d\n", (int)entry->is_visited);
841 static const char *bridge_class;
844 bridge_test_is_bridge_class (MonoClass *class)
846 return !strcmp (bridge_class, class->name);
850 bridge_test_is_bridge_object (MonoObject *object)
856 bridge_test_cross_reference (int num_sccs, MonoGCBridgeSCC **sccs, int num_xrefs, MonoGCBridgeXRef *xrefs)
859 for (i = 0; i < num_sccs; ++i) {
861 // g_print ("--- SCC %d\n", i);
862 for (j = 0; j < sccs [i]->num_objs; ++j) {
863 // g_print (" %s\n", sgen_safe_name (sccs [i]->objs [j]));
864 if (i & 1) /*retain half of the bridged objects */
865 sccs [i]->is_alive = TRUE;
868 for (i = 0; i < num_xrefs; ++i) {
869 g_assert (xrefs [i].src_scc_index >= 0 && xrefs [i].src_scc_index < num_sccs);
870 g_assert (xrefs [i].dst_scc_index >= 0 && xrefs [i].dst_scc_index < num_sccs);
871 // g_print ("%d -> %d\n", xrefs [i].src_scc_index, xrefs [i].dst_scc_index);
875 static MonoClassField *mono_bridge_test_field;
885 test_scc (MonoGCBridgeSCC *scc, int i)
887 int status = BRIDGE_DEAD;
888 mono_field_get_value (scc->objs [i], mono_bridge_test_field, &status);
893 mark_scc (MonoGCBridgeSCC *scc, int value)
896 for (i = 0; i < scc->num_objs; ++i) {
897 if (!test_scc (scc, i)) {
899 mono_field_set_value (scc->objs [i], mono_bridge_test_field, &status);
905 bridge_test_cross_reference2 (int num_sccs, MonoGCBridgeSCC **sccs, int num_xrefs, MonoGCBridgeXRef *xrefs)
910 if (!mono_bridge_test_field) {
911 mono_bridge_test_field = mono_class_get_field_from_name (mono_object_get_class (sccs[0]->objs [0]), "__test");
912 g_assert (mono_bridge_test_field);
915 /*We mark all objects in a scc with live objects as reachable by scc*/
916 for (i = 0; i < num_sccs; ++i) {
918 gboolean live = FALSE;
919 for (j = 0; j < sccs [i]->num_objs; ++j) {
920 if (test_scc (sccs [i], j)) {
927 for (j = 0; j < sccs [i]->num_objs; ++j) {
928 if (!test_scc (sccs [i], j)) {
929 int status = BRIDGE_SAME_SCC;
930 mono_field_set_value (sccs [i]->objs [j], mono_bridge_test_field, &status);
935 /*Now we mark the transitive closure of reachable objects from the xrefs*/
939 /* Mark all objects that are brought to life due to xrefs*/
940 for (i = 0; i < num_xrefs; ++i) {
941 MonoGCBridgeXRef ref = xrefs [i];
942 if (test_scc (sccs [ref.src_scc_index], 0) && !test_scc (sccs [ref.dst_scc_index], 0)) {
944 mark_scc (sccs [ref.dst_scc_index], BRIDGE_XREF);
949 /* keep everything in memory, all we want to do is test persistence */
950 for (i = 0; i < num_sccs; ++i)
951 sccs [i]->is_alive = TRUE;
955 sgen_register_test_bridge_callbacks (const char *bridge_class_name)
957 MonoGCBridgeCallbacks callbacks;
958 callbacks.bridge_version = SGEN_BRIDGE_VERSION;
959 callbacks.is_bridge_class = bridge_test_is_bridge_class;
960 callbacks.is_bridge_object = bridge_test_is_bridge_object;
961 callbacks.cross_references = bridge_class_name[0] == '2' ? bridge_test_cross_reference2 : bridge_test_cross_reference;
962 mono_gc_register_bridge_callbacks (&callbacks);
963 bridge_class = bridge_class_name + (bridge_class_name[0] == '2' ? 1 : 0);