3 * GC implementation using either the installed or included Boehm GC.
5 * Copyright 2001-2003 Ximian, Inc (http://www.ximian.com)
6 * Copyright 2004-2011 Novell, Inc (http://www.novell.com)
7 * Copyright 2011-2012 Xamarin, Inc (http://www.xamarin.com)
8 * Licensed under the MIT license. See LICENSE file in the project root for full license information.
15 #define GC_I_HIDE_POINTERS
16 #include <mono/metadata/gc-internals.h>
17 #include <mono/metadata/mono-gc.h>
18 #include <mono/metadata/profiler-private.h>
19 #include <mono/metadata/class-internals.h>
20 #include <mono/metadata/method-builder.h>
21 #include <mono/metadata/opcodes.h>
22 #include <mono/metadata/domain-internals.h>
23 #include <mono/metadata/metadata-internals.h>
24 #include <mono/metadata/marshal.h>
25 #include <mono/metadata/runtime.h>
26 #include <mono/metadata/handle.h>
27 #include <mono/metadata/sgen-toggleref.h>
28 #include <mono/metadata/w32handle.h>
29 #include <mono/utils/atomic.h>
30 #include <mono/utils/mono-logger-internals.h>
31 #include <mono/utils/mono-memory-model.h>
32 #include <mono/utils/mono-time.h>
33 #include <mono/utils/mono-threads.h>
34 #include <mono/utils/dtrace.h>
35 #include <mono/utils/gc_wrapper.h>
36 #include <mono/utils/mono-os-mutex.h>
37 #include <mono/utils/mono-counters.h>
38 #include <mono/utils/mono-compiler.h>
44 #define THREAD_LOCAL_ALLOC 1
45 #include "private/pthread_support.h"
47 #if defined(PLATFORM_MACOSX) && defined(HAVE_PTHREAD_GET_STACKADDR_NP)
48 void *pthread_get_stackaddr_np(pthread_t);
51 #define GC_NO_DESCRIPTOR ((gpointer)(0 | GC_DS_LENGTH))
52 /*Boehm max heap cannot be smaller than 16MB*/
53 #define MIN_BOEHM_MAX_HEAP_SIZE_IN_MB 16
54 #define MIN_BOEHM_MAX_HEAP_SIZE (MIN_BOEHM_MAX_HEAP_SIZE_IN_MB << 20)
56 static gboolean gc_initialized = FALSE;
57 static mono_mutex_t mono_gc_lock;
59 typedef void (*GC_push_other_roots_proc)(void);
61 static GC_push_other_roots_proc default_push_other_roots;
62 static GHashTable *roots;
65 mono_push_other_roots(void);
68 register_test_toggleref_callback (void);
70 #define BOEHM_GC_BIT_FINALIZER_AWARE 1
71 static MonoGCFinalizerCallbacks fin_callbacks;
75 static mono_mutex_t handle_section;
76 #define lock_handles(handles) mono_os_mutex_lock (&handle_section)
77 #define unlock_handles(handles) mono_os_mutex_unlock (&handle_section)
84 guint slot_hint : 24; /* starting slot for search in bitmap */
85 /* 2^16 appdomains should be enough for everyone (though I know I'll regret this in 20 years) */
86 /* we alloc this only for weak refs, since we can get the domain directly in the other cases */
90 #define EMPTY_HANDLE_DATA(type) {NULL, NULL, 0, (type), 0, NULL}
92 /* weak and weak-track arrays will be allocated in malloc memory
94 static HandleData gc_handles [] = {
95 EMPTY_HANDLE_DATA (HANDLE_WEAK),
96 EMPTY_HANDLE_DATA (HANDLE_WEAK_TRACK),
97 EMPTY_HANDLE_DATA (HANDLE_NORMAL),
98 EMPTY_HANDLE_DATA (HANDLE_PINNED)
102 mono_gc_warning (char *msg, GC_word arg)
104 mono_trace (G_LOG_LEVEL_WARNING, MONO_TRACE_GC, msg, (unsigned long)arg);
107 static void on_gc_notification (GC_EventType event);
108 static void on_gc_heap_resize (size_t new_size);
111 mono_gc_base_init (void)
118 mono_counters_init ();
121 mono_w32handle_init ();
125 * Handle the case when we are called from a thread different from the main thread,
127 * FIXME: Move this to libgc where it belongs.
129 * we used to do this only when running on valgrind,
130 * but it happens also in other setups.
132 #if defined(HAVE_PTHREAD_GETATTR_NP) && defined(HAVE_PTHREAD_ATTR_GETSTACK)
137 pthread_getattr_np (pthread_self (), &attr);
138 pthread_attr_getstack (&attr, &sstart, &size);
139 pthread_attr_destroy (&attr);
140 /*g_print ("stackbottom pth is: %p\n", (char*)sstart + size);*/
141 /* apparently with some linuxthreads implementations sstart can be NULL,
142 * fallback to the more imprecise method (bug# 78096).
145 GC_stackbottom = (char*)sstart + size;
148 gsize stack_bottom = (gsize)&dummy;
149 stack_bottom += 4095;
150 stack_bottom &= ~4095;
151 GC_stackbottom = (char*)stack_bottom;
154 #elif defined(HAVE_PTHREAD_GET_STACKSIZE_NP) && defined(HAVE_PTHREAD_GET_STACKADDR_NP)
155 GC_stackbottom = (char*)pthread_get_stackaddr_np (pthread_self ());
156 #elif defined(__OpenBSD__)
157 # include <pthread_np.h>
162 rslt = pthread_stackseg_np(pthread_self(), &ss);
163 g_assert (rslt == 0);
165 GC_stackbottom = (char*)ss.ss_sp;
170 gsize stack_bottom = (gsize)&dummy;
171 stack_bottom += 4095;
172 stack_bottom &= ~4095;
173 /*g_print ("stackbottom is: %p\n", (char*)stack_bottom);*/
174 GC_stackbottom = (char*)stack_bottom;
178 roots = g_hash_table_new (NULL, NULL);
179 default_push_other_roots = GC_push_other_roots;
180 GC_push_other_roots = mono_push_other_roots;
182 #if !defined(PLATFORM_ANDROID)
183 /* If GC_no_dls is set to true, GC_find_limit is not called. This causes a seg fault on Android. */
187 if ((env = g_getenv ("MONO_GC_DEBUG"))) {
188 char **opts = g_strsplit (env, ",", -1);
189 for (char **ptr = opts; ptr && *ptr; ptr ++) {
191 if (!strcmp (opt, "do-not-finalize")) {
192 mono_do_not_finalize = 1;
193 } else if (!strcmp (opt, "log-finalizers")) {
203 GC_set_warn_proc (mono_gc_warning);
204 GC_finalize_on_demand = 1;
205 GC_finalizer_notifier = mono_gc_finalize_notify;
207 GC_init_gcj_malloc (5, NULL);
208 GC_allow_register_threads ();
210 if ((env = g_getenv ("MONO_GC_PARAMS"))) {
211 char **ptr, **opts = g_strsplit (env, ",", -1);
212 for (ptr = opts; *ptr; ++ptr) {
214 if (g_str_has_prefix (opt, "max-heap-size=")) {
217 opt = strchr (opt, '=') + 1;
218 if (*opt && mono_gc_parse_environment_string_extract_number (opt, &max_heap)) {
219 if (max_heap < MIN_BOEHM_MAX_HEAP_SIZE) {
220 fprintf (stderr, "max-heap-size must be at least %dMb.\n", MIN_BOEHM_MAX_HEAP_SIZE_IN_MB);
223 GC_set_max_heap_size (max_heap);
225 fprintf (stderr, "max-heap-size must be an integer.\n");
229 } else if (g_str_has_prefix (opt, "toggleref-test")) {
230 register_test_toggleref_callback ();
233 /* Could be a parameter for sgen */
235 fprintf (stderr, "MONO_GC_PARAMS must be a comma-delimited list of one or more of the following:\n");
236 fprintf (stderr, " max-heap-size=N (where N is an integer, possibly with a k, m or a g suffix)\n");
245 mono_thread_callbacks_init ();
246 mono_thread_info_init (sizeof (MonoThreadInfo));
247 mono_os_mutex_init (&mono_gc_lock);
248 mono_os_mutex_init_recursive (&handle_section);
250 mono_thread_info_attach ();
252 GC_set_on_collection_event (on_gc_notification);
253 GC_on_heap_resize = on_gc_heap_resize;
255 gc_initialized = TRUE;
259 mono_gc_base_cleanup (void)
261 GC_finalizer_notifier = NULL;
266 * \param generation GC generation identifier
268 * Perform a garbage collection for the given generation, higher numbers
269 * mean usually older objects. Collecting a high-numbered generation
270 * implies collecting also the lower-numbered generations.
271 * The maximum value for \p generation can be retrieved with a call to
272 * \c mono_gc_max_generation, so this function is usually called as:
274 * <code>mono_gc_collect (mono_gc_max_generation ());</code>
277 mono_gc_collect (int generation)
279 #ifndef DISABLE_PERFCOUNTERS
280 mono_perfcounters->gc_induced++;
286 * mono_gc_max_generation:
288 * Get the maximum generation number used by the current garbage
289 * collector. The value will be 0 for the Boehm collector, 1 or more
290 * for the generational collectors.
292 * Returns: the maximum generation number.
295 mono_gc_max_generation (void)
301 * mono_gc_get_generation:
302 * \param object a managed object
304 * Get the garbage collector's generation that \p object belongs to.
305 * Use this has a hint only.
307 * \returns a garbage collector generation number
310 mono_gc_get_generation (MonoObject *object)
316 * mono_gc_collection_count:
317 * \param generation a GC generation number
319 * Get how many times a garbage collection has been performed
320 * for the given \p generation number.
322 * \returns the number of garbage collections
325 mono_gc_collection_count (int generation)
331 * mono_gc_add_memory_pressure:
332 * \param value amount of bytes
334 * Adjust the garbage collector's view of how many bytes of memory
335 * are indirectly referenced by managed objects (for example unmanaged
336 * memory holding image or other binary data).
337 * This is a hint only to the garbage collector algorithm.
338 * Note that negative amounts of p value will decrease the memory
342 mono_gc_add_memory_pressure (gint64 value)
347 * mono_gc_get_used_size:
349 * Get the approximate amount of memory used by managed objects.
351 * Returns: the amount of memory used in bytes
354 mono_gc_get_used_size (void)
356 return GC_get_heap_size () - GC_get_free_bytes ();
360 * mono_gc_get_heap_size:
362 * Get the amount of memory used by the garbage collector.
364 * Returns: the size of the heap in bytes
367 mono_gc_get_heap_size (void)
369 return GC_get_heap_size ();
373 mono_gc_is_gc_thread (void)
375 return GC_thread_is_registered ();
379 mono_gc_thread_attach (MonoThreadInfo* info)
381 struct GC_stack_base sb;
384 /* TODO: use GC_get_stack_base instead of baseptr. */
385 sb.mem_base = info->stack_end;
386 res = GC_register_my_thread (&sb);
387 if (res == GC_UNIMPLEMENTED)
388 return NULL; /* Cannot happen with GC v7+. */
390 info->handle_stack = mono_handle_stack_alloc ();
396 mono_gc_thread_detach_with_lock (MonoThreadInfo *p)
398 MonoNativeThreadId tid;
400 tid = mono_thread_info_get_tid (p);
402 if (p->runtime_thread)
403 mono_threads_add_joinable_thread ((gpointer)tid);
405 mono_handle_stack_free (p->handle_stack);
409 mono_gc_thread_in_critical_region (MonoThreadInfo *info)
415 mono_object_is_alive (MonoObject* o)
417 return GC_is_marked ((ptr_t)o);
421 mono_gc_walk_heap (int flags, MonoGCReferences callback, void *data)
426 static gint64 gc_start_time;
429 on_gc_notification (GC_EventType event)
431 MonoGCEvent e = (MonoGCEvent)event;
434 case MONO_GC_EVENT_PRE_STOP_WORLD:
435 MONO_GC_WORLD_STOP_BEGIN ();
438 case MONO_GC_EVENT_POST_STOP_WORLD:
439 MONO_GC_WORLD_STOP_END ();
442 case MONO_GC_EVENT_PRE_START_WORLD:
443 MONO_GC_WORLD_RESTART_BEGIN (1);
446 case MONO_GC_EVENT_POST_START_WORLD:
447 MONO_GC_WORLD_RESTART_END (1);
450 case MONO_GC_EVENT_START:
452 #ifndef DISABLE_PERFCOUNTERS
453 if (mono_perfcounters)
454 mono_perfcounters->gc_collections0++;
456 gc_stats.major_gc_count ++;
457 gc_start_time = mono_100ns_ticks ();
460 case MONO_GC_EVENT_END:
462 #if defined(ENABLE_DTRACE) && defined(__sun__)
463 /* This works around a dtrace -G problem on Solaris.
464 Limit its actual use to when the probe is enabled. */
465 if (MONO_GC_END_ENABLED ())
469 #ifndef DISABLE_PERFCOUNTERS
470 if (mono_perfcounters) {
471 guint64 heap_size = GC_get_heap_size ();
472 guint64 used_size = heap_size - GC_get_free_bytes ();
473 mono_perfcounters->gc_total_bytes = used_size;
474 mono_perfcounters->gc_committed_bytes = heap_size;
475 mono_perfcounters->gc_reserved_bytes = heap_size;
476 mono_perfcounters->gc_gen0size = heap_size;
479 gc_stats.major_gc_time += mono_100ns_ticks () - gc_start_time;
480 mono_trace_message (MONO_TRACE_GC, "gc took %" G_GINT64_FORMAT " usecs", (mono_100ns_ticks () - gc_start_time) / 10);
486 mono_profiler_gc_event (e, 0);
489 case MONO_GC_EVENT_PRE_STOP_WORLD:
490 mono_thread_info_suspend_lock ();
491 mono_profiler_gc_event (MONO_GC_EVENT_PRE_STOP_WORLD_LOCKED, 0);
493 case MONO_GC_EVENT_POST_START_WORLD:
494 mono_thread_info_suspend_unlock ();
495 mono_profiler_gc_event (MONO_GC_EVENT_POST_START_WORLD_UNLOCKED, 0);
504 on_gc_heap_resize (size_t new_size)
506 guint64 heap_size = GC_get_heap_size ();
507 #ifndef DISABLE_PERFCOUNTERS
508 if (mono_perfcounters) {
509 mono_perfcounters->gc_committed_bytes = heap_size;
510 mono_perfcounters->gc_reserved_bytes = heap_size;
511 mono_perfcounters->gc_gen0size = heap_size;
514 mono_profiler_gc_heap_resize (new_size);
523 register_root (gpointer arg)
525 RootData* root_data = arg;
526 g_hash_table_insert (roots, root_data->start, root_data->end);
531 mono_gc_register_root (char *start, size_t size, void *descr, MonoGCRootSource source, const char *msg)
534 root_data.start = start;
535 /* Boehm root processing requires one byte past end of region to be scanned */
536 root_data.end = start + size + 1;
537 GC_call_with_alloc_lock (register_root, &root_data);
543 mono_gc_register_root_wbarrier (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
545 return mono_gc_register_root (start, size, descr, source, msg);
549 deregister_root (gpointer arg)
551 gboolean removed = g_hash_table_remove (roots, arg);
557 mono_gc_deregister_root (char* addr)
559 GC_call_with_alloc_lock (deregister_root, addr);
563 push_root (gpointer key, gpointer value, gpointer user_data)
565 GC_push_all (key, value);
569 mono_push_other_roots (void)
571 g_hash_table_foreach (roots, push_root, NULL);
572 if (default_push_other_roots)
573 default_push_other_roots ();
577 mono_gc_weak_link_add (void **link_addr, MonoObject *obj, gboolean track)
579 /* libgc requires that we use HIDE_POINTER... */
580 *link_addr = (void*)HIDE_POINTER (obj);
582 GC_REGISTER_LONG_LINK (link_addr, obj);
584 GC_GENERAL_REGISTER_DISAPPEARING_LINK (link_addr, obj);
588 mono_gc_weak_link_remove (void **link_addr, gboolean track)
591 GC_unregister_long_link (link_addr);
593 GC_unregister_disappearing_link (link_addr);
598 reveal_link (gpointer link_addr)
600 void **link_a = (void **)link_addr;
601 return REVEAL_POINTER (*link_a);
605 mono_gc_weak_link_get (void **link_addr)
607 MonoObject *obj = (MonoObject *)GC_call_with_alloc_lock (reveal_link, link_addr);
608 if (obj == (MonoObject *) -1)
614 mono_gc_make_descr_for_string (gsize *bitmap, int numbits)
616 return mono_gc_make_descr_from_bitmap (bitmap, numbits);
620 mono_gc_make_descr_for_object (gsize *bitmap, int numbits, size_t obj_size)
622 return mono_gc_make_descr_from_bitmap (bitmap, numbits);
626 mono_gc_make_descr_for_array (int vector, gsize *elem_bitmap, int numbits, size_t elem_size)
628 /* libgc has no usable support for arrays... */
629 return GC_NO_DESCRIPTOR;
633 mono_gc_make_descr_from_bitmap (gsize *bitmap, int numbits)
635 /* It seems there are issues when the bitmap doesn't fit: play it safe */
637 return GC_NO_DESCRIPTOR;
639 return (gpointer)GC_make_descriptor ((GC_bitmap)bitmap, numbits);
643 mono_gc_make_vector_descr (void)
649 mono_gc_make_root_descr_all_refs (int numbits)
655 mono_gc_alloc_fixed (size_t size, void *descr, MonoGCRootSource source, const char *msg)
657 return GC_MALLOC_UNCOLLECTABLE (size);
661 mono_gc_free_fixed (void* addr)
667 mono_gc_alloc_obj (MonoVTable *vtable, size_t size)
671 if (!vtable->klass->has_references) {
672 obj = (MonoObject *)GC_MALLOC_ATOMIC (size);
673 if (G_UNLIKELY (!obj))
676 obj->vtable = vtable;
677 obj->synchronisation = NULL;
679 memset ((char *) obj + sizeof (MonoObject), 0, size - sizeof (MonoObject));
680 } else if (vtable->gc_descr != GC_NO_DESCRIPTOR) {
681 obj = (MonoObject *)GC_GCJ_MALLOC (size, vtable);
682 if (G_UNLIKELY (!obj))
685 obj = (MonoObject *)GC_MALLOC (size);
686 if (G_UNLIKELY (!obj))
689 obj->vtable = vtable;
692 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS))
693 mono_profiler_allocation (obj);
699 mono_gc_alloc_vector (MonoVTable *vtable, size_t size, uintptr_t max_length)
703 if (!vtable->klass->has_references) {
704 obj = (MonoArray *)GC_MALLOC_ATOMIC (size);
705 if (G_UNLIKELY (!obj))
708 obj->obj.vtable = vtable;
709 obj->obj.synchronisation = NULL;
711 memset ((char *) obj + sizeof (MonoObject), 0, size - sizeof (MonoObject));
712 } else if (vtable->gc_descr != GC_NO_DESCRIPTOR) {
713 obj = (MonoArray *)GC_GCJ_MALLOC (size, vtable);
714 if (G_UNLIKELY (!obj))
717 obj = (MonoArray *)GC_MALLOC (size);
718 if (G_UNLIKELY (!obj))
721 obj->obj.vtable = vtable;
724 obj->max_length = max_length;
726 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS))
727 mono_profiler_allocation (&obj->obj);
733 mono_gc_alloc_array (MonoVTable *vtable, size_t size, uintptr_t max_length, uintptr_t bounds_size)
737 if (!vtable->klass->has_references) {
738 obj = (MonoArray *)GC_MALLOC_ATOMIC (size);
739 if (G_UNLIKELY (!obj))
742 obj->obj.vtable = vtable;
743 obj->obj.synchronisation = NULL;
745 memset ((char *) obj + sizeof (MonoObject), 0, size - sizeof (MonoObject));
746 } else if (vtable->gc_descr != GC_NO_DESCRIPTOR) {
747 obj = (MonoArray *)GC_GCJ_MALLOC (size, vtable);
748 if (G_UNLIKELY (!obj))
751 obj = (MonoArray *)GC_MALLOC (size);
752 if (G_UNLIKELY (!obj))
755 obj->obj.vtable = vtable;
758 obj->max_length = max_length;
761 obj->bounds = (MonoArrayBounds *) ((char *) obj + size - bounds_size);
763 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS))
764 mono_profiler_allocation (&obj->obj);
770 mono_gc_alloc_string (MonoVTable *vtable, size_t size, gint32 len)
772 MonoString *obj = (MonoString *)GC_MALLOC_ATOMIC (size);
773 if (G_UNLIKELY (!obj))
776 obj->object.vtable = vtable;
777 obj->object.synchronisation = NULL;
779 obj->chars [len] = 0;
781 if (G_UNLIKELY (mono_profiler_events & MONO_PROFILE_ALLOCATIONS))
782 mono_profiler_allocation (&obj->object);
788 mono_gc_alloc_mature (MonoVTable *vtable, size_t size)
790 return mono_gc_alloc_obj (vtable, size);
794 mono_gc_alloc_pinned_obj (MonoVTable *vtable, size_t size)
796 return mono_gc_alloc_obj (vtable, size);
800 mono_gc_invoke_finalizers (void)
802 /* There is a bug in GC_invoke_finalizer () in versions <= 6.2alpha4:
803 * the 'mem_freed' variable is not initialized when there are no
804 * objects to finalize, which leads to strange behavior later on.
805 * The check is necessary to work around that bug.
807 if (GC_should_invoke_finalizers ())
808 return GC_invoke_finalizers ();
813 mono_gc_pending_finalizers (void)
815 return GC_should_invoke_finalizers ();
819 mono_gc_wbarrier_set_field (MonoObject *obj, gpointer field_ptr, MonoObject* value)
821 *(void**)field_ptr = value;
825 mono_gc_wbarrier_set_arrayref (MonoArray *arr, gpointer slot_ptr, MonoObject* value)
827 *(void**)slot_ptr = value;
831 mono_gc_wbarrier_arrayref_copy (gpointer dest_ptr, gpointer src_ptr, int count)
833 mono_gc_memmove_aligned (dest_ptr, src_ptr, count * sizeof (gpointer));
837 mono_gc_wbarrier_generic_store (gpointer ptr, MonoObject* value)
839 *(void**)ptr = value;
843 mono_gc_wbarrier_generic_store_atomic (gpointer ptr, MonoObject *value)
845 InterlockedWritePointer ((volatile gpointer *)ptr, value);
849 mono_gc_wbarrier_generic_nostore (gpointer ptr)
854 mono_gc_wbarrier_value_copy (gpointer dest, gpointer src, int count, MonoClass *klass)
856 mono_gc_memmove_atomic (dest, src, count * mono_class_value_size (klass, NULL));
860 mono_gc_wbarrier_object_copy (MonoObject* obj, MonoObject *src)
862 /* do not copy the sync state */
863 mono_gc_memmove_aligned ((char*)obj + sizeof (MonoObject), (char*)src + sizeof (MonoObject),
864 mono_object_class (obj)->instance_size - sizeof (MonoObject));
868 mono_gc_clear_domain (MonoDomain *domain)
873 mono_gc_suspend_finalizers (void)
878 mono_gc_get_suspend_signal (void)
880 return GC_get_suspend_signal ();
884 mono_gc_get_restart_signal (void)
886 return GC_get_thr_restart_signal ();
889 #if defined(USE_COMPILER_TLS) && defined(__linux__) && (defined(__i386__) || defined(__x86_64__))
890 extern __thread void* GC_thread_tls;
891 #include "metadata-internals.h"
897 while (!(v & (1 << i)))
904 ATYPE_FREEPTR_FOR_BOX,
912 create_allocator (int atype, int tls_key, gboolean slowpath)
914 int index_var, bytes_var, my_fl_var, my_entry_var;
915 guint32 no_freelist_branch, not_small_enough_branch = 0;
916 guint32 size_overflow_branch = 0;
917 MonoMethodBuilder *mb;
919 MonoMethodSignature *csig;
920 const char *name = NULL;
923 g_assert_not_reached ();
925 if (atype == ATYPE_FREEPTR) {
926 name = slowpath ? "SlowAllocPtrfree" : "AllocPtrfree";
927 } else if (atype == ATYPE_FREEPTR_FOR_BOX) {
928 name = slowpath ? "SlowAllocPtrfreeBox" : "AllocPtrfreeBox";
929 } else if (atype == ATYPE_NORMAL) {
930 name = slowpath ? "SlowAlloc" : "Alloc";
931 } else if (atype == ATYPE_GCJ) {
932 name = slowpath ? "SlowAllocGcj" : "AllocGcj";
933 } else if (atype == ATYPE_STRING) {
934 name = slowpath ? "SlowAllocString" : "AllocString";
936 g_assert_not_reached ();
939 csig = mono_metadata_signature_alloc (mono_defaults.corlib, 2);
941 if (atype == ATYPE_STRING) {
942 csig->ret = &mono_defaults.string_class->byval_arg;
943 csig->params [0] = &mono_defaults.int_class->byval_arg;
944 csig->params [1] = &mono_defaults.int32_class->byval_arg;
946 csig->ret = &mono_defaults.object_class->byval_arg;
947 csig->params [0] = &mono_defaults.int_class->byval_arg;
948 csig->params [1] = &mono_defaults.int32_class->byval_arg;
951 mb = mono_mb_new (mono_defaults.object_class, name, MONO_WRAPPER_ALLOC);
954 goto always_slowpath;
956 bytes_var = mono_mb_add_local (mb, &mono_defaults.int32_class->byval_arg);
957 if (atype == ATYPE_STRING) {
958 /* a string alloator method takes the args: (vtable, len) */
959 /* bytes = (offsetof (MonoString, chars) + ((len + 1) * 2)); */
960 mono_mb_emit_ldarg (mb, 1);
961 mono_mb_emit_icon (mb, 1);
962 mono_mb_emit_byte (mb, MONO_CEE_ADD);
963 mono_mb_emit_icon (mb, 1);
964 mono_mb_emit_byte (mb, MONO_CEE_SHL);
965 // sizeof (MonoString) might include padding
966 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoString, chars));
967 mono_mb_emit_byte (mb, MONO_CEE_ADD);
968 mono_mb_emit_stloc (mb, bytes_var);
970 mono_mb_emit_ldarg (mb, 1);
971 mono_mb_emit_stloc (mb, bytes_var);
974 /* this is needed for strings/arrays only as the other big types are never allocated with this method */
975 if (atype == ATYPE_STRING) {
977 /* if (!SMALL_ENOUGH (bytes)) jump slow_path;*/
978 mono_mb_emit_ldloc (mb, bytes_var);
979 mono_mb_emit_icon (mb, (NFREELISTS-1) * GRANULARITY);
980 not_small_enough_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BGT_UN_S);
981 /* check for overflow */
982 mono_mb_emit_ldloc (mb, bytes_var);
983 mono_mb_emit_icon (mb, sizeof (MonoString));
984 size_overflow_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLE_UN_S);
987 /* int index = INDEX_FROM_BYTES(bytes); */
988 index_var = mono_mb_add_local (mb, &mono_defaults.int32_class->byval_arg);
990 mono_mb_emit_ldloc (mb, bytes_var);
991 mono_mb_emit_icon (mb, GRANULARITY - 1);
992 mono_mb_emit_byte (mb, MONO_CEE_ADD);
993 mono_mb_emit_icon (mb, shift_amount (GRANULARITY));
994 mono_mb_emit_byte (mb, MONO_CEE_SHR_UN);
995 mono_mb_emit_icon (mb, shift_amount (sizeof (gpointer)));
996 mono_mb_emit_byte (mb, MONO_CEE_SHL);
997 /* index var is already adjusted into bytes */
998 mono_mb_emit_stloc (mb, index_var);
1000 my_fl_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1001 my_entry_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1002 /* my_fl = ((GC_thread)tsd) -> ptrfree_freelists + index; */
1003 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1004 mono_mb_emit_byte (mb, 0x0D); /* CEE_MONO_TLS */
1005 mono_mb_emit_i4 (mb, tls_key);
1006 if (atype == ATYPE_FREEPTR || atype == ATYPE_FREEPTR_FOR_BOX || atype == ATYPE_STRING)
1007 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (struct GC_Thread_Rep, tlfs)
1008 + G_STRUCT_OFFSET (struct thread_local_freelists,
1009 ptrfree_freelists));
1010 else if (atype == ATYPE_NORMAL)
1011 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (struct GC_Thread_Rep, tlfs)
1012 + G_STRUCT_OFFSET (struct thread_local_freelists,
1014 else if (atype == ATYPE_GCJ)
1015 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (struct GC_Thread_Rep, tlfs)
1016 + G_STRUCT_OFFSET (struct thread_local_freelists,
1019 g_assert_not_reached ();
1020 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1021 mono_mb_emit_ldloc (mb, index_var);
1022 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1023 mono_mb_emit_stloc (mb, my_fl_var);
1025 /* my_entry = *my_fl; */
1026 mono_mb_emit_ldloc (mb, my_fl_var);
1027 mono_mb_emit_byte (mb, MONO_CEE_LDIND_I);
1028 mono_mb_emit_stloc (mb, my_entry_var);
1030 /* if (EXPECT((word)my_entry >= HBLKSIZE, 1)) { */
1031 mono_mb_emit_ldloc (mb, my_entry_var);
1032 mono_mb_emit_icon (mb, HBLKSIZE);
1033 no_freelist_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLT_UN_S);
1035 /* ptr_t next = obj_link(my_entry); *my_fl = next; */
1036 mono_mb_emit_ldloc (mb, my_fl_var);
1037 mono_mb_emit_ldloc (mb, my_entry_var);
1038 mono_mb_emit_byte (mb, MONO_CEE_LDIND_I);
1039 mono_mb_emit_byte (mb, MONO_CEE_STIND_I);
1041 /* set the vtable and clear the words in the object */
1042 mono_mb_emit_ldloc (mb, my_entry_var);
1043 mono_mb_emit_ldarg (mb, 0);
1044 mono_mb_emit_byte (mb, MONO_CEE_STIND_I);
1046 if (atype == ATYPE_FREEPTR) {
1047 int start_var, end_var, start_loop;
1048 /* end = my_entry + bytes; start = my_entry + sizeof (gpointer);
1050 start_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1051 end_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1052 mono_mb_emit_ldloc (mb, my_entry_var);
1053 mono_mb_emit_ldloc (mb, bytes_var);
1054 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1055 mono_mb_emit_stloc (mb, end_var);
1056 mono_mb_emit_ldloc (mb, my_entry_var);
1057 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoObject, synchronisation));
1058 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1059 mono_mb_emit_stloc (mb, start_var);
1063 * } while (start < end);
1065 start_loop = mono_mb_get_label (mb);
1066 mono_mb_emit_ldloc (mb, start_var);
1067 mono_mb_emit_icon (mb, 0);
1068 mono_mb_emit_byte (mb, MONO_CEE_STIND_I);
1069 mono_mb_emit_ldloc (mb, start_var);
1070 mono_mb_emit_icon (mb, sizeof (gpointer));
1071 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1072 mono_mb_emit_stloc (mb, start_var);
1074 mono_mb_emit_ldloc (mb, start_var);
1075 mono_mb_emit_ldloc (mb, end_var);
1076 mono_mb_emit_byte (mb, MONO_CEE_BLT_UN_S);
1077 mono_mb_emit_byte (mb, start_loop - (mono_mb_get_label (mb) + 1));
1078 } else if (atype == ATYPE_FREEPTR_FOR_BOX || atype == ATYPE_STRING) {
1079 /* need to clear just the sync pointer */
1080 mono_mb_emit_ldloc (mb, my_entry_var);
1081 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoObject, synchronisation));
1082 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1083 mono_mb_emit_icon (mb, 0);
1084 mono_mb_emit_byte (mb, MONO_CEE_STIND_I);
1087 if (atype == ATYPE_STRING) {
1088 /* need to set length and clear the last char */
1089 /* s->length = len; */
1090 mono_mb_emit_ldloc (mb, my_entry_var);
1091 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoString, length));
1092 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1093 mono_mb_emit_ldarg (mb, 1);
1094 mono_mb_emit_byte (mb, MONO_CEE_STIND_I4);
1095 /* s->chars [len] = 0; */
1096 mono_mb_emit_ldloc (mb, my_entry_var);
1097 mono_mb_emit_ldloc (mb, bytes_var);
1098 mono_mb_emit_icon (mb, 2);
1099 mono_mb_emit_byte (mb, MONO_CEE_SUB);
1100 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1101 mono_mb_emit_icon (mb, 0);
1102 mono_mb_emit_byte (mb, MONO_CEE_STIND_I2);
1105 /* return my_entry; */
1106 mono_mb_emit_ldloc (mb, my_entry_var);
1107 mono_mb_emit_byte (mb, MONO_CEE_RET);
1109 mono_mb_patch_short_branch (mb, no_freelist_branch);
1110 if (not_small_enough_branch > 0)
1111 mono_mb_patch_short_branch (mb, not_small_enough_branch);
1112 if (size_overflow_branch > 0)
1113 mono_mb_patch_short_branch (mb, size_overflow_branch);
1115 /* the slow path: we just call back into the runtime */
1117 if (atype == ATYPE_STRING) {
1118 mono_mb_emit_ldarg (mb, 1);
1119 mono_mb_emit_icall (mb, ves_icall_string_alloc);
1121 mono_mb_emit_ldarg (mb, 0);
1122 mono_mb_emit_icall (mb, ves_icall_object_new_specific);
1125 mono_mb_emit_byte (mb, MONO_CEE_RET);
1127 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
1128 info->d.alloc.gc_name = "boehm";
1129 info->d.alloc.alloc_type = atype;
1130 mb->init_locals = FALSE;
1132 res = mono_mb_create (mb, csig, 8, info);
1138 static MonoMethod* alloc_method_cache [ATYPE_NUM];
1139 static MonoMethod* slowpath_alloc_method_cache [ATYPE_NUM];
1142 mono_gc_is_critical_method (MonoMethod *method)
1146 for (i = 0; i < ATYPE_NUM; ++i)
1147 if (method == alloc_method_cache [i] || method == slowpath_alloc_method_cache [i])
1154 * If possible, generate a managed method that can quickly allocate objects in class
1155 * @klass. The method will typically have an thread-local inline allocation sequence.
1156 * The signature of the called method is:
1157 * object allocate (MonoVTable *vtable)
1158 * Some of the logic here is similar to mono_class_get_allocation_ftn () i object.c,
1160 * The thread local alloc logic is taken from libgc/pthread_support.c.
1164 mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size)
1169 * Tls implementation changed, we jump to tls native getters/setters.
1170 * Is boehm managed allocator ok with this ? Do we even care ?
1174 if (!SMALL_ENOUGH (klass->instance_size))
1176 if (mono_class_has_finalizer (klass) || mono_class_is_marshalbyref (klass))
1178 if (mono_profiler_get_events () & (MONO_PROFILE_ALLOCATIONS | MONO_PROFILE_STATISTICAL))
1182 if (mono_class_is_open_constructed_type (&klass->byval_arg))
1184 if (klass->byval_arg.type == MONO_TYPE_STRING) {
1185 atype = ATYPE_STRING;
1186 } else if (!known_instance_size) {
1188 } else if (!klass->has_references) {
1190 atype = ATYPE_FREEPTR_FOR_BOX;
1192 atype = ATYPE_FREEPTR;
1196 * disabled because we currently do a runtime choice anyway, to
1197 * deal with multiple appdomains.
1198 if (vtable->gc_descr != GC_NO_DESCRIPTOR)
1201 atype = ATYPE_NORMAL;
1204 return mono_gc_get_managed_allocator_by_type (atype, MANAGED_ALLOCATOR_REGULAR);
1208 mono_gc_get_managed_array_allocator (MonoClass *klass)
1214 * mono_gc_get_managed_allocator_by_type:
1216 * Return a managed allocator method corresponding to allocator type ATYPE.
1219 mono_gc_get_managed_allocator_by_type (int atype, ManagedAllocatorVariant variant)
1222 gboolean slowpath = variant != MANAGED_ALLOCATOR_REGULAR;
1223 MonoMethod **cache = slowpath ? slowpath_alloc_method_cache : alloc_method_cache;
1227 res = cache [atype];
1231 res = create_allocator (atype, -1, slowpath);
1232 mono_os_mutex_lock (&mono_gc_lock);
1233 if (cache [atype]) {
1234 mono_free_method (res);
1235 res = cache [atype];
1237 mono_memory_barrier ();
1238 cache [atype] = res;
1240 mono_os_mutex_unlock (&mono_gc_lock);
1245 mono_gc_get_managed_allocator_types (void)
1251 mono_gc_get_write_barrier (void)
1253 g_assert_not_reached ();
1260 mono_gc_is_critical_method (MonoMethod *method)
1266 mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size)
1272 mono_gc_get_managed_array_allocator (MonoClass *klass)
1278 mono_gc_get_managed_allocator_by_type (int atype, ManagedAllocatorVariant variant)
1284 mono_gc_get_managed_allocator_types (void)
1290 mono_gc_get_write_barrier (void)
1292 g_assert_not_reached ();
1299 mono_gc_get_specific_write_barrier (gboolean is_concurrent)
1301 g_assert_not_reached ();
1306 mono_gc_get_aligned_size_for_allocator (int size)
1312 mono_gc_get_gc_name (void)
1318 mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data)
1320 return GC_call_with_alloc_lock (func, data);
1324 mono_gc_get_description (void)
1326 return g_strdup (DEFAULT_GC_NAME);
1330 mono_gc_set_desktop_mode (void)
1336 mono_gc_is_moving (void)
1342 mono_gc_is_disabled (void)
1344 if (GC_dont_gc || g_hasenv ("GC_DONT_GC"))
1351 mono_gc_wbarrier_range_copy (gpointer _dest, gpointer _src, int size)
1353 g_assert_not_reached ();
1357 mono_gc_get_range_copy_func (void)
1359 return &mono_gc_wbarrier_range_copy;
1363 mono_gc_get_card_table (int *shift_bits, gpointer *card_mask)
1365 g_assert_not_reached ();
1370 mono_gc_card_table_nursery_check (void)
1372 g_assert_not_reached ();
1377 mono_gc_get_nursery (int *shift_bits, size_t *size)
1383 mono_gc_precise_stack_mark_enabled (void)
1389 mono_gc_get_logfile (void)
1395 mono_gc_params_set (const char* options)
1400 mono_gc_debug_set (const char* options)
1405 mono_gc_conservatively_scan_area (void *start, void *end)
1407 g_assert_not_reached ();
1411 mono_gc_scan_object (void *obj, void *gc_data)
1413 g_assert_not_reached ();
1418 mono_gc_get_bitmap_for_descr (void *descr, int *numbits)
1420 g_assert_not_reached ();
1425 mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks)
1430 mono_gc_set_stack_end (void *stack_end)
1434 void mono_gc_set_skip_thread (gboolean value)
1439 mono_gc_register_for_finalization (MonoObject *obj, void *user_data)
1444 /* This assertion is not valid when GC_DEBUG is defined */
1445 g_assert (GC_base (obj) == (char*)obj - offset);
1448 GC_REGISTER_FINALIZER_NO_ORDER ((char*)obj - offset, (GC_finalization_proc)user_data, GUINT_TO_POINTER (offset), NULL, NULL);
1453 mono_gc_pthread_create (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg)
1455 /* it is being replaced by GC_pthread_create on some
1456 * platforms, see libgc/include/gc_pthread_redirects.h */
1457 return pthread_create (new_thread, attr, start_routine, arg);
1462 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved)
1464 return GC_DllMain (module_handle, reason, reserved);
1469 mono_gc_get_vtable_bits (MonoClass *klass)
1471 if (fin_callbacks.is_class_finalization_aware) {
1472 if (fin_callbacks.is_class_finalization_aware (klass))
1473 return BOEHM_GC_BIT_FINALIZER_AWARE;
1479 * mono_gc_register_altstack:
1481 * Register the dimensions of the normal stack and altstack with the collector.
1482 * Currently, STACK/STACK_SIZE is only used when the thread is suspended while it is on an altstack.
1485 mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size)
1487 GC_register_altstack (stack, stack_size, altstack, altstack_size);
1491 mono_gc_get_los_limit (void)
1497 mono_gc_set_string_length (MonoString *str, gint32 new_length)
1499 mono_unichar2 *new_end = str->chars + new_length;
1501 /* zero the discarded string. This null-delimits the string and allows
1502 * the space to be reclaimed by SGen. */
1504 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2));
1505 str->length = new_length;
1509 mono_gc_user_markers_supported (void)
1515 mono_gc_make_root_descr_user (MonoGCRootMarkFunc marker)
1517 g_assert_not_reached ();
1521 /* Toggleref support */
1524 mono_gc_toggleref_add (MonoObject *object, mono_bool strong_ref)
1526 if (GC_toggleref_add ((GC_PTR)object, (int)strong_ref) != GC_SUCCESS)
1527 g_error ("GC_toggleref_add failed\n");
1531 mono_gc_toggleref_register_callback (MonoToggleRefStatus (*proccess_toggleref) (MonoObject *obj))
1533 GC_set_toggleref_func ((GC_ToggleRefStatus (*) (GC_PTR obj)) proccess_toggleref);
1536 /* Test support code */
1538 static MonoToggleRefStatus
1539 test_toggleref_callback (MonoObject *obj)
1541 static MonoClassField *mono_toggleref_test_field;
1542 MonoToggleRefStatus status = MONO_TOGGLE_REF_DROP;
1544 if (!mono_toggleref_test_field) {
1545 mono_toggleref_test_field = mono_class_get_field_from_name (mono_object_get_class (obj), "__test");
1546 g_assert (mono_toggleref_test_field);
1549 mono_field_get_value (obj, mono_toggleref_test_field, &status);
1550 printf ("toggleref-cb obj %d\n", status);
1555 register_test_toggleref_callback (void)
1557 mono_gc_toggleref_register_callback (test_toggleref_callback);
1561 is_finalization_aware (MonoObject *obj)
1563 MonoVTable *vt = obj->vtable;
1564 return (vt->gc_bits & BOEHM_GC_BIT_FINALIZER_AWARE) == BOEHM_GC_BIT_FINALIZER_AWARE;
1568 fin_notifier (MonoObject *obj)
1570 if (is_finalization_aware (obj))
1571 fin_callbacks.object_queued_for_finalization (obj);
1575 mono_gc_register_finalizer_callbacks (MonoGCFinalizerCallbacks *callbacks)
1577 if (callbacks->version != MONO_GC_FINALIZER_EXTENSION_VERSION)
1578 g_error ("Invalid finalizer callback version. Expected %d but got %d\n", MONO_GC_FINALIZER_EXTENSION_VERSION, callbacks->version);
1580 fin_callbacks = *callbacks;
1582 GC_set_await_finalize_proc ((void (*) (GC_PTR))fin_notifier);
1585 #define BITMAP_SIZE (sizeof (*((HandleData *)NULL)->bitmap) * CHAR_BIT)
1587 static inline gboolean
1588 slot_occupied (HandleData *handles, guint slot) {
1589 return handles->bitmap [slot / BITMAP_SIZE] & (1 << (slot % BITMAP_SIZE));
1593 vacate_slot (HandleData *handles, guint slot) {
1594 handles->bitmap [slot / BITMAP_SIZE] &= ~(1 << (slot % BITMAP_SIZE));
1598 occupy_slot (HandleData *handles, guint slot) {
1599 handles->bitmap [slot / BITMAP_SIZE] |= 1 << (slot % BITMAP_SIZE);
1603 find_first_unset (guint32 bitmap)
1606 for (i = 0; i < 32; ++i) {
1607 if (!(bitmap & (1 << i)))
1614 handle_data_alloc_entries (HandleData *handles)
1617 if (MONO_GC_HANDLE_TYPE_IS_WEAK (handles->type)) {
1618 handles->entries = (void **)g_malloc0 (sizeof (*handles->entries) * handles->size);
1619 handles->domain_ids = (guint16 *)g_malloc0 (sizeof (*handles->domain_ids) * handles->size);
1621 handles->entries = (void **)mono_gc_alloc_fixed (sizeof (*handles->entries) * handles->size, NULL, MONO_ROOT_SOURCE_GC_HANDLE, "gc handles table");
1623 handles->bitmap = (guint32 *)g_malloc0 (handles->size / CHAR_BIT);
1627 handle_data_next_unset (HandleData *handles)
1630 for (slot = handles->slot_hint; slot < handles->size / BITMAP_SIZE; ++slot) {
1631 if (handles->bitmap [slot] == 0xffffffff)
1633 handles->slot_hint = slot;
1634 return find_first_unset (handles->bitmap [slot]);
1640 handle_data_first_unset (HandleData *handles)
1643 for (slot = 0; slot < handles->slot_hint; ++slot) {
1644 if (handles->bitmap [slot] == 0xffffffff)
1646 handles->slot_hint = slot;
1647 return find_first_unset (handles->bitmap [slot]);
1652 /* Returns the index of the current slot in the bitmap. */
1654 handle_data_grow (HandleData *handles, gboolean track)
1656 guint32 *new_bitmap;
1657 guint32 new_size = handles->size * 2; /* always double: we memset to 0 based on this below */
1659 /* resize and copy the bitmap */
1660 new_bitmap = (guint32 *)g_malloc0 (new_size / CHAR_BIT);
1661 memcpy (new_bitmap, handles->bitmap, handles->size / CHAR_BIT);
1662 g_free (handles->bitmap);
1663 handles->bitmap = new_bitmap;
1665 /* resize and copy the entries */
1666 if (MONO_GC_HANDLE_TYPE_IS_WEAK (handles->type)) {
1668 guint16 *domain_ids;
1670 domain_ids = (guint16 *)g_malloc0 (sizeof (*handles->domain_ids) * new_size);
1671 entries = (void **)g_malloc0 (sizeof (*handles->entries) * new_size);
1672 memcpy (domain_ids, handles->domain_ids, sizeof (*handles->domain_ids) * handles->size);
1673 for (i = 0; i < handles->size; ++i) {
1674 MonoObject *obj = mono_gc_weak_link_get (&(handles->entries [i]));
1676 mono_gc_weak_link_add (&(entries [i]), obj, track);
1677 mono_gc_weak_link_remove (&(handles->entries [i]), track);
1679 g_assert (!handles->entries [i]);
1682 g_free (handles->entries);
1683 g_free (handles->domain_ids);
1684 handles->entries = entries;
1685 handles->domain_ids = domain_ids;
1688 entries = (void **)mono_gc_alloc_fixed (sizeof (*handles->entries) * new_size, NULL, MONO_ROOT_SOURCE_GC_HANDLE, "gc handles table");
1689 mono_gc_memmove_aligned (entries, handles->entries, sizeof (*handles->entries) * handles->size);
1690 mono_gc_free_fixed (handles->entries);
1691 handles->entries = entries;
1693 handles->slot_hint = handles->size / BITMAP_SIZE;
1694 handles->size = new_size;
1698 alloc_handle (HandleData *handles, MonoObject *obj, gboolean track)
1702 lock_handles (handles);
1704 handle_data_alloc_entries (handles);
1705 i = handle_data_next_unset (handles);
1706 if (i == -1 && handles->slot_hint != 0)
1707 i = handle_data_first_unset (handles);
1709 handle_data_grow (handles, track);
1712 slot = handles->slot_hint * BITMAP_SIZE + i;
1713 occupy_slot (handles, slot);
1714 handles->entries [slot] = NULL;
1715 if (MONO_GC_HANDLE_TYPE_IS_WEAK (handles->type)) {
1716 /*FIXME, what to use when obj == null?*/
1717 handles->domain_ids [slot] = (obj ? mono_object_get_domain (obj) : mono_domain_get ())->domain_id;
1719 mono_gc_weak_link_add (&(handles->entries [slot]), obj, track);
1721 handles->entries [slot] = obj;
1724 #ifndef DISABLE_PERFCOUNTERS
1725 mono_perfcounters->gc_num_handles++;
1727 unlock_handles (handles);
1728 res = MONO_GC_HANDLE (slot, handles->type);
1729 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_CREATED, handles->type, res, obj);
1734 * mono_gchandle_new:
1735 * \param obj managed object to get a handle for
1736 * \param pinned whether the object should be pinned
1738 * This returns a handle that wraps the object, this is used to keep a
1739 * reference to a managed object from the unmanaged world and preventing the
1740 * object from being disposed.
1742 * If \p pinned is false the address of the object can not be obtained, if it is
1743 * true the address of the object can be obtained. This will also pin the
1744 * object so it will not be possible by a moving garbage collector to move the
1747 * \returns a handle that can be used to access the object from
1751 mono_gchandle_new (MonoObject *obj, gboolean pinned)
1753 return alloc_handle (&gc_handles [pinned? HANDLE_PINNED: HANDLE_NORMAL], obj, FALSE);
1757 * mono_gchandle_new_weakref:
1758 * \param obj managed object to get a handle for
1759 * \param track_resurrection Determines how long to track the object, if this is set to TRUE, the object is tracked after finalization, if FALSE, the object is only tracked up until the point of finalization.
1761 * This returns a weak handle that wraps the object, this is used to
1762 * keep a reference to a managed object from the unmanaged world.
1763 * Unlike the \c mono_gchandle_new the object can be reclaimed by the
1764 * garbage collector. In this case the value of the GCHandle will be
1767 * If \p track_resurrection is TRUE the object will be tracked through
1768 * finalization and if the object is resurrected during the execution
1769 * of the finalizer, then the returned weakref will continue to hold
1770 * a reference to the object. If \p track_resurrection is FALSE, then
1771 * the weak reference's target will become NULL as soon as the object
1772 * is passed on to the finalizer.
1774 * \returns a handle that can be used to access the object from
1778 mono_gchandle_new_weakref (MonoObject *obj, gboolean track_resurrection)
1780 return alloc_handle (&gc_handles [track_resurrection? HANDLE_WEAK_TRACK: HANDLE_WEAK], obj, track_resurrection);
1784 * mono_gchandle_get_target:
1785 * \param gchandle a GCHandle's handle.
1787 * The handle was previously created by calling \c mono_gchandle_new or
1788 * \c mono_gchandle_new_weakref.
1790 * \returns A pointer to the \c MonoObject* represented by the handle or
1791 * NULL for a collected object if using a weakref handle.
1794 mono_gchandle_get_target (guint32 gchandle)
1796 guint slot = MONO_GC_HANDLE_SLOT (gchandle);
1797 guint type = MONO_GC_HANDLE_TYPE (gchandle);
1798 HandleData *handles = &gc_handles [type];
1799 MonoObject *obj = NULL;
1800 if (type >= HANDLE_TYPE_MAX)
1803 lock_handles (handles);
1804 if (slot < handles->size && slot_occupied (handles, slot)) {
1805 if (MONO_GC_HANDLE_TYPE_IS_WEAK (handles->type)) {
1806 obj = mono_gc_weak_link_get (&handles->entries [slot]);
1808 obj = (MonoObject *)handles->entries [slot];
1811 /* print a warning? */
1813 unlock_handles (handles);
1814 /*g_print ("get target of entry %d of type %d: %p\n", slot, handles->type, obj);*/
1819 mono_gchandle_set_target (guint32 gchandle, MonoObject *obj)
1821 guint slot = MONO_GC_HANDLE_SLOT (gchandle);
1822 guint type = MONO_GC_HANDLE_TYPE (gchandle);
1823 HandleData *handles = &gc_handles [type];
1824 MonoObject *old_obj = NULL;
1826 g_assert (type < HANDLE_TYPE_MAX);
1827 lock_handles (handles);
1828 if (slot < handles->size && slot_occupied (handles, slot)) {
1829 if (MONO_GC_HANDLE_TYPE_IS_WEAK (handles->type)) {
1830 old_obj = (MonoObject *)handles->entries [slot];
1831 if (handles->entries [slot])
1832 mono_gc_weak_link_remove (&handles->entries [slot], handles->type == HANDLE_WEAK_TRACK);
1834 mono_gc_weak_link_add (&handles->entries [slot], obj, handles->type == HANDLE_WEAK_TRACK);
1835 /*FIXME, what to use when obj == null?*/
1836 handles->domain_ids [slot] = (obj ? mono_object_get_domain (obj) : mono_domain_get ())->domain_id;
1838 handles->entries [slot] = obj;
1841 /* print a warning? */
1843 /*g_print ("changed entry %d of type %d to object %p (in slot: %p)\n", slot, handles->type, obj, handles->entries [slot]);*/
1844 unlock_handles (handles);
1848 mono_gc_is_null (void)
1854 * mono_gchandle_is_in_domain:
1855 * \param gchandle a GCHandle's handle.
1856 * \param domain An application domain.
1858 * Use this function to determine if the \p gchandle points to an
1859 * object allocated in the specified \p domain.
1861 * \returns TRUE if the object wrapped by the \p gchandle belongs to the specific \p domain.
1864 mono_gchandle_is_in_domain (guint32 gchandle, MonoDomain *domain)
1866 guint slot = MONO_GC_HANDLE_SLOT (gchandle);
1867 guint type = MONO_GC_HANDLE_TYPE (gchandle);
1868 HandleData *handles = &gc_handles [type];
1869 gboolean result = FALSE;
1871 if (type >= HANDLE_TYPE_MAX)
1874 lock_handles (handles);
1875 if (slot < handles->size && slot_occupied (handles, slot)) {
1876 if (MONO_GC_HANDLE_TYPE_IS_WEAK (handles->type)) {
1877 result = domain->domain_id == handles->domain_ids [slot];
1880 obj = (MonoObject *)handles->entries [slot];
1884 result = domain == mono_object_domain (obj);
1887 /* print a warning? */
1889 unlock_handles (handles);
1894 * mono_gchandle_free:
1895 * \param gchandle a GCHandle's handle.
1897 * Frees the \p gchandle handle. If there are no outstanding
1898 * references, the garbage collector can reclaim the memory of the
1902 mono_gchandle_free (guint32 gchandle)
1904 guint slot = MONO_GC_HANDLE_SLOT (gchandle);
1905 guint type = MONO_GC_HANDLE_TYPE (gchandle);
1906 HandleData *handles = &gc_handles [type];
1907 if (type >= HANDLE_TYPE_MAX)
1910 lock_handles (handles);
1911 if (slot < handles->size && slot_occupied (handles, slot)) {
1912 if (MONO_GC_HANDLE_TYPE_IS_WEAK (handles->type)) {
1913 if (handles->entries [slot])
1914 mono_gc_weak_link_remove (&handles->entries [slot], handles->type == HANDLE_WEAK_TRACK);
1916 handles->entries [slot] = NULL;
1918 vacate_slot (handles, slot);
1920 /* print a warning? */
1922 #ifndef DISABLE_PERFCOUNTERS
1923 mono_perfcounters->gc_num_handles--;
1925 /*g_print ("freed entry %d of type %d\n", slot, handles->type);*/
1926 unlock_handles (handles);
1927 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_DESTROYED, handles->type, gchandle, NULL);
1931 * mono_gchandle_free_domain:
1932 * \param domain domain that is unloading
1934 * Function used internally to cleanup any GC handle for objects belonging
1935 * to the specified domain during appdomain unload.
1938 mono_gchandle_free_domain (MonoDomain *domain)
1942 for (type = HANDLE_TYPE_MIN; type < HANDLE_PINNED; ++type) {
1944 HandleData *handles = &gc_handles [type];
1945 lock_handles (handles);
1946 for (slot = 0; slot < handles->size; ++slot) {
1947 if (!slot_occupied (handles, slot))
1949 if (MONO_GC_HANDLE_TYPE_IS_WEAK (type)) {
1950 if (domain->domain_id == handles->domain_ids [slot]) {
1951 vacate_slot (handles, slot);
1952 if (handles->entries [slot])
1953 mono_gc_weak_link_remove (&handles->entries [slot], handles->type == HANDLE_WEAK_TRACK);
1956 if (handles->entries [slot] && mono_object_domain (handles->entries [slot]) == domain) {
1957 vacate_slot (handles, slot);
1958 handles->entries [slot] = NULL;
1962 unlock_handles (handles);
1968 MONO_EMPTY_SOURCE_FILE (boehm_gc);
1969 #endif /* no Boehm GC */