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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)
41 static const void *copy_labels [] = { &&LAB_0, &&LAB_1, &&LAB_2, &&LAB_3, &&LAB_4, &&LAB_5, &&LAB_6, &&LAB_7, &&LAB_8 };
44 DEBUG (9, g_assert (vt->klass->inited));
45 DEBUG (9, fprintf (gc_debug_file, " (to %p, %s size: %lu)\n", destination, ((MonoObject*)obj)->vtable->klass->name, (unsigned long)objsize));
46 binary_protocol_copy (obj, destination, vt, objsize);
49 if (objsize <= sizeof (gpointer) * 8) {
50 mword *dest = (mword*)destination;
51 goto *copy_labels [objsize / sizeof (gpointer)];
53 (dest) [7] = ((mword*)obj) [7];
55 (dest) [6] = ((mword*)obj) [6];
57 (dest) [5] = ((mword*)obj) [5];
59 (dest) [4] = ((mword*)obj) [4];
61 (dest) [3] = ((mword*)obj) [3];
63 (dest) [2] = ((mword*)obj) [2];
65 (dest) [1] = ((mword*)obj) [1];
71 /*can't trust memcpy doing word copies */
72 mono_gc_memmove (destination + sizeof (mword), (char*)obj + sizeof (mword), objsize - sizeof (mword));
75 mono_gc_memmove (destination + sizeof (mword), (char*)obj + sizeof (mword), objsize - sizeof (mword));
77 /* adjust array->bounds */
78 DEBUG (9, g_assert (vt->gc_descr));
79 if (G_UNLIKELY (vt->rank && ((MonoArray*)obj)->bounds)) {
80 MonoArray *array = (MonoArray*)destination;
81 array->bounds = (MonoArrayBounds*)((char*)destination + ((char*)((MonoArray*)obj)->bounds - (char*)obj));
82 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)));
84 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_GC_MOVES))
85 sgen_register_moved_object (obj, destination);
88 DEBUG (9, fprintf (gc_debug_file, "Enqueuing gray object %p (%s)\n", obj, sgen_safe_name (obj)));
89 GRAY_OBJECT_ENQUEUE (queue, obj);
94 static __declspec(noinline) void*
96 static G_GNUC_UNUSED void* __attribute__((noinline))
98 copy_object_no_checks (void *obj, SgenGrayQueue *queue)
100 MonoVTable *vt = ((MonoObject*)obj)->vtable;
101 gboolean has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
102 mword objsize = SGEN_ALIGN_UP (sgen_par_object_get_size (vt, (MonoObject*)obj));
103 char *destination = collector_serial_alloc_for_promotion (obj, objsize, has_references);
105 if (G_UNLIKELY (!destination)) {
106 collector_pin_object (obj, queue);
107 sgen_set_pinned_from_failed_allocation (objsize);
111 *(MonoVTable**)destination = vt;
112 par_copy_object_no_checks (destination, vt, obj, objsize, has_references ? queue : NULL);
114 /* set the forwarding pointer */
115 SGEN_FORWARD_OBJECT (obj, destination);
120 #ifdef GENERATE_COPY_FUNCTIONS
122 extern long long stat_nursery_copy_object_failed_to_space; /* from sgen-gc.c */
124 #if defined(SGEN_SIMPLE_NURSERY)
125 #define serial_copy_object simple_nursery_serial_copy_object
126 #define parallel_copy_object simple_nursery_parallel_copy_object
128 #elif defined (SGEN_SPLIT_NURSERY)
130 #define serial_copy_object split_nursery_serial_copy_object
131 #define parallel_copy_object split_nursery_parallel_copy_object
134 #error "Please define GC_CONF_NAME"
138 * This is how the copying happens from the nursery to the old generation.
139 * We assume that at this time all the pinned objects have been identified and
141 * We run scan_object() for each pinned object so that each referenced
142 * objects if possible are copied. The new gray objects created can have
143 * scan_object() run on them right away, too.
144 * Then we run copy_object() for the precisely tracked roots. At this point
145 * all the roots are either gray or black. We run scan_object() on the gray
146 * objects until no more gray objects are created.
147 * At the end of the process we walk again the pinned list and we unmark
148 * the pinned flag. As we go we also create the list of free space for use
149 * in the next allocation runs.
151 * We need to remember objects from the old generation that point to the new one
152 * (or just addresses?).
154 * copy_object could be made into a macro once debugged (use inline for now).
158 static __forceinline void
160 static inline void __attribute__((always_inline))
162 serial_copy_object (void **obj_slot, SgenGrayQueue *queue)
165 char *obj = *obj_slot;
167 DEBUG (9, g_assert (current_collection_generation == GENERATION_NURSERY));
169 HEAVY_STAT (++stat_copy_object_called_nursery);
171 if (!sgen_ptr_in_nursery (obj)) {
172 HEAVY_STAT (++stat_nursery_copy_object_failed_from_space);
176 DEBUG (9, fprintf (gc_debug_file, "Precise copy of %p from %p", obj, obj_slot));
179 * Before we can copy the object we must make sure that we are
180 * allowed to, i.e. that the object not pinned, not already
181 * forwarded or belongs to the nursery To Space.
184 if ((forwarded = SGEN_OBJECT_IS_FORWARDED (obj))) {
185 DEBUG (9, g_assert ((*(MonoVTable**)SGEN_LOAD_VTABLE(obj))->gc_descr));
186 DEBUG (9, fprintf (gc_debug_file, " (already forwarded to %p)\n", forwarded));
187 HEAVY_STAT (++stat_nursery_copy_object_failed_forwarded);
188 *obj_slot = forwarded;
191 if (SGEN_OBJECT_IS_PINNED (obj)) {
192 DEBUG (9, g_assert (((MonoVTable*)SGEN_LOAD_VTABLE(obj))->gc_descr));
193 DEBUG (9, fprintf (gc_debug_file, " (pinned, no change)\n"));
194 HEAVY_STAT (++stat_nursery_copy_object_failed_pinned);
198 if (sgen_nursery_is_to_space (obj)) {
199 DEBUG (9, g_assert (((MonoVTable*)SGEN_LOAD_VTABLE(obj))->gc_descr));
200 DEBUG (9, fprintf (gc_debug_file, " (tospace, no change)\n"));
201 HEAVY_STAT (++stat_nursery_copy_object_failed_to_space);
205 HEAVY_STAT (++stat_objects_copied_nursery);
207 *obj_slot = copy_object_no_checks (obj, queue);
211 parallel_copy_object (void **obj_slot, SgenGrayQueue *queue)
213 char *obj = *obj_slot;
214 mword vtable_word, objsize;
217 gboolean has_references;
219 DEBUG (9, g_assert (current_collection_generation == GENERATION_NURSERY));
221 HEAVY_STAT (++stat_copy_object_called_nursery);
223 if (!sgen_ptr_in_nursery (obj)) {
224 HEAVY_STAT (++stat_nursery_copy_object_failed_from_space);
228 vtable_word = *(mword*)obj;
229 vt = (MonoVTable*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
232 * Before we can copy the object we must make sure that we are
233 * allowed to, i.e. that the object not pinned, not already
234 * forwarded and not in the nursery To Space.
237 if (vtable_word & SGEN_FORWARDED_BIT) {
238 HEAVY_STAT (++stat_nursery_copy_object_failed_forwarded);
242 if (vtable_word & SGEN_PINNED_BIT) {
243 HEAVY_STAT (++stat_nursery_copy_object_failed_pinned);
247 if (sgen_nursery_is_to_space (obj)) {
248 HEAVY_STAT (++stat_nursery_copy_object_failed_to_space);
252 HEAVY_STAT (++stat_objects_copied_nursery);
254 objsize = SGEN_ALIGN_UP (sgen_par_object_get_size (vt, (MonoObject*)obj));
255 has_references = SGEN_VTABLE_HAS_REFERENCES (vt);
257 destination = collector_parallel_alloc_for_promotion (obj, objsize, has_references);
259 if (G_UNLIKELY (!destination)) {
260 sgen_parallel_pin_or_update (obj_slot, obj, vt, queue);
264 *(MonoVTable**)destination = vt;
266 if (SGEN_CAS_PTR ((void*)obj, (void*)((mword)destination | SGEN_FORWARDED_BIT), vt) == vt) {
267 par_copy_object_no_checks (destination, vt, obj, objsize, has_references ? queue : NULL);
271 /* FIXME: unify with code in major_copy_or_mark_object() */
273 /* FIXME: Give destination back to the allocator. */
274 /*The major collector only needs the first word zeroed and nursery requires all bits to be. */
275 if (!sgen_ptr_in_nursery (destination))
276 *(void**)destination = NULL;
278 memset (destination, 0, objsize);
280 vtable_word = *(mword*)obj;
281 g_assert (vtable_word & SGEN_FORWARDED_BIT);
283 obj = (void*)(vtable_word & ~SGEN_VTABLE_BITS_MASK);
287 HEAVY_STAT (++stat_slots_allocated_in_vain);