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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;
31 extern long long stat_slots_allocated_in_vain;
34 * This function can be used even if the vtable of obj is not valid
35 * anymore, which is the case in the parallel collector.
38 par_copy_object_no_checks (char *destination, MonoVTable *vt, void *obj, mword objsize, SgenGrayQueue *queue)
40 static const void *copy_labels [] = { &&LAB_0, &&LAB_1, &&LAB_2, &&LAB_3, &&LAB_4, &&LAB_5, &&LAB_6, &&LAB_7, &&LAB_8 };
42 DEBUG (9, g_assert (vt->klass->inited));
43 DEBUG (9, fprintf (gc_debug_file, " (to %p, %s size: %lu)\n", destination, ((MonoObject*)obj)->vtable->klass->name, (unsigned long)objsize));
44 binary_protocol_copy (obj, destination, vt, objsize);
46 if (objsize <= sizeof (gpointer) * 8) {
47 mword *dest = (mword*)destination;
48 goto *copy_labels [objsize / sizeof (gpointer)];
50 (dest) [7] = ((mword*)obj) [7];
52 (dest) [6] = ((mword*)obj) [6];
54 (dest) [5] = ((mword*)obj) [5];
56 (dest) [4] = ((mword*)obj) [4];
58 (dest) [3] = ((mword*)obj) [3];
60 (dest) [2] = ((mword*)obj) [2];
62 (dest) [1] = ((mword*)obj) [1];
68 /*can't trust memcpy doing word copies */
69 mono_gc_memmove (destination + sizeof (mword), (char*)obj + sizeof (mword), objsize - sizeof (mword));
71 /* adjust array->bounds */
72 DEBUG (9, g_assert (vt->gc_descr));
73 if (G_UNLIKELY (vt->rank && ((MonoArray*)obj)->bounds)) {
74 MonoArray *array = (MonoArray*)destination;
75 array->bounds = (MonoArrayBounds*)((char*)destination + ((char*)((MonoArray*)obj)->bounds - (char*)obj));
76 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)));
78 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_GC_MOVES))
79 sgen_register_moved_object (obj, destination);
82 DEBUG (9, fprintf (gc_debug_file, "Enqueuing gray object %p (%s)\n", obj, sgen_safe_name (obj)));
83 GRAY_OBJECT_ENQUEUE (queue, obj);
87 static G_GNUC_UNUSED void*
88 copy_object_no_checks (void *obj, SgenGrayQueue *queue)
90 MonoVTable *vt = ((MonoObject*)obj)->vtable;
91 gboolean has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
92 mword objsize = SGEN_ALIGN_UP (sgen_par_object_get_size (vt, (MonoObject*)obj));
93 char *destination = collector_serial_alloc_for_promotion (obj, objsize, has_references);
95 if (G_UNLIKELY (!destination)) {
96 collector_pin_object (obj, queue);
97 sgen_set_pinned_from_failed_allocation (objsize);
101 *(MonoVTable**)destination = vt;
102 par_copy_object_no_checks (destination, vt, obj, objsize, has_references ? queue : NULL);
104 /* set the forwarding pointer */
105 SGEN_FORWARD_OBJECT (obj, destination);
110 #ifdef GENERATE_COPY_FUNCTIONS
112 extern long long stat_nursery_copy_object_failed_to_space; /* from sgen-gc.c */
115 * This is how the copying happens from the nursery to the old generation.
116 * We assume that at this time all the pinned objects have been identified and
118 * We run scan_object() for each pinned object so that each referenced
119 * objects if possible are copied. The new gray objects created can have
120 * scan_object() run on them right away, too.
121 * Then we run copy_object() for the precisely tracked roots. At this point
122 * all the roots are either gray or black. We run scan_object() on the gray
123 * objects until no more gray objects are created.
124 * At the end of the process we walk again the pinned list and we unmark
125 * the pinned flag. As we go we also create the list of free space for use
126 * in the next allocation runs.
128 * We need to remember objects from the old generation that point to the new one
129 * (or just addresses?).
131 * copy_object could be made into a macro once debugged (use inline for now).
135 serial_copy_object (void **obj_slot, SgenGrayQueue *queue)
138 char *obj = *obj_slot;
140 DEBUG (9, g_assert (current_collection_generation == GENERATION_NURSERY));
142 HEAVY_STAT (++stat_copy_object_called_nursery);
144 if (!sgen_ptr_in_nursery (obj)) {
145 HEAVY_STAT (++stat_nursery_copy_object_failed_from_space);
149 DEBUG (9, fprintf (gc_debug_file, "Precise copy of %p from %p", obj, obj_slot));
152 * Before we can copy the object we must make sure that we are
153 * allowed to, i.e. that the object not pinned, not already
154 * forwarded or belongs to the nursery To Space.
157 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
158 DEBUG (9, g_assert ((*(MonoVTable**)SGEN_LOAD_VTABLE(obj))->gc_descr));
159 DEBUG (9, fprintf (gc_debug_file, " (already forwarded to %p)\n", forwarded));
160 HEAVY_STAT (++stat_nursery_copy_object_failed_forwarded);
161 *obj_slot = forwarded;
164 if (SGEN_OBJECT_IS_PINNED (obj)) {
165 DEBUG (9, g_assert (((MonoVTable*)SGEN_LOAD_VTABLE(obj))->gc_descr));
166 DEBUG (9, fprintf (gc_debug_file, " (pinned, no change)\n"));
167 HEAVY_STAT (++stat_nursery_copy_object_failed_pinned);
171 if (sgen_nursery_is_to_space (obj)) {
172 DEBUG (9, g_assert (((MonoVTable*)SGEN_LOAD_VTABLE(obj))->gc_descr));
173 DEBUG (9, fprintf (gc_debug_file, " (tospace, no change)\n"));
174 HEAVY_STAT (++stat_nursery_copy_object_failed_to_space);
178 HEAVY_STAT (++stat_objects_copied_nursery);
180 *obj_slot = copy_object_no_checks (obj, queue);
184 parallel_copy_object (void **obj_slot, SgenGrayQueue *queue)
186 char *obj = *obj_slot;
187 mword vtable_word, objsize;
190 gboolean has_references;
192 DEBUG (9, g_assert (current_collection_generation == GENERATION_NURSERY));
194 HEAVY_STAT (++stat_copy_object_called_nursery);
196 if (!sgen_ptr_in_nursery (obj)) {
197 HEAVY_STAT (++stat_nursery_copy_object_failed_from_space);
201 vtable_word = *(mword*)obj;
202 vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
205 * Before we can copy the object we must make sure that we are
206 * allowed to, i.e. that the object not pinned, not already
207 * forwarded and not in the nursery To Space.
210 if (vtable_word & SGEN_FORWARDED_BIT) {
211 HEAVY_STAT (++stat_nursery_copy_object_failed_forwarded);
215 if (vtable_word & SGEN_PINNED_BIT) {
216 HEAVY_STAT (++stat_nursery_copy_object_failed_pinned);
220 if (sgen_nursery_is_to_space (obj)) {
221 HEAVY_STAT (++stat_nursery_copy_object_failed_to_space);
225 HEAVY_STAT (++stat_objects_copied_nursery);
227 objsize = SGEN_ALIGN_UP (sgen_par_object_get_size (vt, (MonoObject*)obj));
228 has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
230 destination = collector_parallel_alloc_for_promotion (obj, objsize, has_references);
232 if (G_UNLIKELY (!destination)) {
233 sgen_parallel_pin_or_update (obj_slot, obj, vt, queue);
237 *(MonoVTable**)destination = vt;
239 if (SGEN_CAS_PTR ((void*)obj, (void*)((mword)destination | SGEN_FORWARDED_BIT), vt) == vt) {
240 par_copy_object_no_checks (destination, vt, obj, objsize, has_references ? queue : NULL);
244 /* FIXME: unify with code in major_copy_or_mark_object() */
246 /* FIXME: Give destination back to the allocator. */
247 /*The major collector only needs the first word zeroed and nursery requires all bits to be. */
248 if (!sgen_ptr_in_nursery (destination))
249 *(void**)destination = NULL;
251 memset (destination, 0, objsize);
253 vtable_word = *(mword*)obj;
254 g_assert (vtable_word & SGEN_FORWARDED_BIT);
256 obj = (void*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
260 HEAVY_STAT (++stat_slots_allocated_in_vain);