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3 * Copyright 2003-2010 Novell, Inc.
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24 extern long long stat_copy_object_called_nursery;
25 extern long long stat_objects_copied_nursery;
27 extern long long stat_nursery_copy_object_failed_from_space;
28 extern long long stat_nursery_copy_object_failed_forwarded;
29 extern long long stat_nursery_copy_object_failed_pinned;
32 * This function can be used even if the vtable of obj is not valid
33 * anymore, which is the case in the parallel collector.
36 par_copy_object_no_checks (char *destination, MonoVTable *vt, void *obj, mword objsize, SgenGrayQueue *queue)
38 static const void *copy_labels [] = { &&LAB_0, &&LAB_1, &&LAB_2, &&LAB_3, &&LAB_4, &&LAB_5, &&LAB_6, &&LAB_7, &&LAB_8 };
40 DEBUG (9, g_assert (vt->klass->inited));
41 DEBUG (9, fprintf (gc_debug_file, " (to %p, %s size: %lu)\n", destination, ((MonoObject*)obj)->vtable->klass->name, (unsigned long)objsize));
42 binary_protocol_copy (obj, destination, vt, objsize);
44 if (objsize <= sizeof (gpointer) * 8) {
45 mword *dest = (mword*)destination;
46 goto *copy_labels [objsize / sizeof (gpointer)];
48 (dest) [7] = ((mword*)obj) [7];
50 (dest) [6] = ((mword*)obj) [6];
52 (dest) [5] = ((mword*)obj) [5];
54 (dest) [4] = ((mword*)obj) [4];
56 (dest) [3] = ((mword*)obj) [3];
58 (dest) [2] = ((mword*)obj) [2];
60 (dest) [1] = ((mword*)obj) [1];
66 /*can't trust memcpy doing word copies */
67 mono_gc_memmove (destination + sizeof (mword), (char*)obj + sizeof (mword), objsize - sizeof (mword));
69 /* adjust array->bounds */
70 DEBUG (9, g_assert (vt->gc_descr));
71 if (G_UNLIKELY (vt->rank && ((MonoArray*)obj)->bounds)) {
72 MonoArray *array = (MonoArray*)destination;
73 array->bounds = (MonoArrayBounds*)((char*)destination + ((char*)((MonoArray*)obj)->bounds - (char*)obj));
74 DEBUG (9, fprintf (gc_debug_file, "Array instance %p: size: %lu, rank: %d, length: %lu\n", array, (unsigned long)objsize, vt->rank, (unsigned long)mono_array_length (array)));
76 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_GC_MOVES))
77 mono_sgen_register_moved_object (obj, destination);
80 DEBUG (9, fprintf (gc_debug_file, "Enqueuing gray object %p (%s)\n", obj, mono_sgen_safe_name (obj)));
81 GRAY_OBJECT_ENQUEUE (queue, obj);
86 copy_object_no_checks (void *obj, SgenGrayQueue *queue)
88 MonoVTable *vt = ((MonoObject*)obj)->vtable;
89 gboolean has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
90 mword objsize = SGEN_ALIGN_UP (mono_sgen_par_object_get_size (vt, (MonoObject*)obj));
91 char *destination = major_alloc_object (objsize, has_references);
93 if (G_UNLIKELY (!destination)) {
94 if (ptr_in_nursery (obj)) {
95 mono_sgen_pin_object (obj, queue);
97 g_assert (objsize <= SGEN_MAX_SMALL_OBJ_SIZE);
98 pin_major_object (obj, queue);
103 *(MonoVTable**)destination = vt;
104 par_copy_object_no_checks (destination, vt, obj, objsize, has_references ? queue : NULL);
106 /* set the forwarding pointer */
107 SGEN_FORWARD_OBJECT (obj, destination);
113 * This is how the copying happens from the nursery to the old generation.
114 * We assume that at this time all the pinned objects have been identified and
116 * We run scan_object() for each pinned object so that each referenced
117 * objects if possible are copied. The new gray objects created can have
118 * scan_object() run on them right away, too.
119 * Then we run copy_object() for the precisely tracked roots. At this point
120 * all the roots are either gray or black. We run scan_object() on the gray
121 * objects until no more gray objects are created.
122 * At the end of the process we walk again the pinned list and we unmark
123 * the pinned flag. As we go we also create the list of free space for use
124 * in the next allocation runs.
126 * We need to remember objects from the old generation that point to the new one
127 * (or just addresses?).
129 * copy_object could be made into a macro once debugged (use inline for now).
133 nopar_copy_object (void **obj_slot, SgenGrayQueue *queue)
136 char *obj = *obj_slot;
138 DEBUG (9, g_assert (current_collection_generation == GENERATION_NURSERY));
140 HEAVY_STAT (++stat_copy_object_called_nursery);
142 if (!ptr_in_nursery (obj)) {
143 HEAVY_STAT (++stat_nursery_copy_object_failed_from_space);
147 DEBUG (9, fprintf (gc_debug_file, "Precise copy of %p from %p", obj, obj_slot));
150 * Before we can copy the object we must make sure that we are
151 * allowed to, i.e. that the object not pinned or not already
155 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
156 DEBUG (9, g_assert (((MonoVTable*)SGEN_LOAD_VTABLE(obj))->gc_descr));
157 DEBUG (9, fprintf (gc_debug_file, " (already forwarded to %p)\n", forwarded));
158 HEAVY_STAT (++stat_nursery_copy_object_failed_forwarded);
159 *obj_slot = forwarded;
162 if (SGEN_OBJECT_IS_PINNED (obj)) {
163 DEBUG (9, g_assert (((MonoVTable*)SGEN_LOAD_VTABLE(obj))->gc_descr));
164 DEBUG (9, fprintf (gc_debug_file, " (pinned, no change)\n"));
165 HEAVY_STAT (++stat_nursery_copy_object_failed_pinned);
169 HEAVY_STAT (++stat_objects_copied_nursery);
171 *obj_slot = copy_object_no_checks (obj, queue);
174 #ifdef SGEN_PARALLEL_MARK
176 copy_object (void **obj_slot, SgenGrayQueue *queue)
178 char *obj = *obj_slot;
179 mword vtable_word, objsize;
182 gboolean has_references;
184 DEBUG (9, g_assert (current_collection_generation == GENERATION_NURSERY));
186 HEAVY_STAT (++stat_copy_object_called_nursery);
188 if (!ptr_in_nursery (obj)) {
189 HEAVY_STAT (++stat_nursery_copy_object_failed_from_space);
193 vtable_word = *(mword*)obj;
194 vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
197 * Before we can copy the object we must make sure that we are
198 * allowed to, i.e. that the object not pinned or not already
202 if (vtable_word & SGEN_FORWARDED_BIT) {
203 HEAVY_STAT (++stat_nursery_copy_object_failed_forwarded);
207 if (vtable_word & SGEN_PINNED_BIT) {
208 HEAVY_STAT (++stat_nursery_copy_object_failed_pinned);
212 HEAVY_STAT (++stat_objects_copied_nursery);
214 objsize = SGEN_ALIGN_UP (mono_sgen_par_object_get_size (vt, (MonoObject*)obj));
215 has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
217 destination = alloc_obj_par (objsize, FALSE, has_references);
219 if (G_UNLIKELY (!destination)) {
220 pin_or_update_par (obj_slot, obj, vt, queue);
224 *(MonoVTable**)destination = vt;
226 if (SGEN_CAS_PTR ((void*)obj, (void*)((mword)destination | SGEN_FORWARDED_BIT), vt) == vt) {
227 par_copy_object_no_checks (destination, vt, obj, objsize, has_references ? queue : NULL);
231 /* FIXME: unify with code in major_copy_or_mark_object() */
233 /* FIXME: Give destination back to the allocator. */
234 *(void**)destination = NULL;
236 vtable_word = *(mword*)obj;
237 g_assert (vtable_word & SGEN_FORWARDED_BIT);
239 obj = (void*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
243 ++stat_slots_allocated_in_vain;
248 copy_object (void **obj_slot, SgenGrayQueue *queue)
250 nopar_copy_object (obj_slot, queue);
254 #define FILL_COLLECTOR_COPY_OBJECT(collector) do { \
255 (collector)->copy_object = copy_object; \
256 (collector)->nopar_copy_object = nopar_copy_object; \