2 * boehm-gc.c: GC implementation using either the installed or included Boehm GC.
4 * Copyright 2001-2003 Ximian, Inc (http://www.ximian.com)
5 * Copyright 2004-2011 Novell, Inc (http://www.novell.com)
6 * Copyright 2011-2012 Xamarin, Inc (http://www.xamarin.com)
13 #define GC_I_HIDE_POINTERS
14 #include <mono/metadata/gc-internal.h>
15 #include <mono/metadata/mono-gc.h>
16 #include <mono/metadata/profiler-private.h>
17 #include <mono/metadata/class-internals.h>
18 #include <mono/metadata/method-builder.h>
19 #include <mono/metadata/opcodes.h>
20 #include <mono/metadata/domain-internals.h>
21 #include <mono/metadata/metadata-internals.h>
22 #include <mono/metadata/marshal.h>
23 #include <mono/metadata/runtime.h>
24 #include <mono/metadata/sgen-toggleref.h>
25 #include <mono/utils/atomic.h>
26 #include <mono/utils/mono-logger-internal.h>
27 #include <mono/utils/mono-memory-model.h>
28 #include <mono/utils/mono-time.h>
29 #include <mono/utils/mono-threads.h>
30 #include <mono/utils/dtrace.h>
31 #include <mono/utils/gc_wrapper.h>
32 #include <mono/utils/mono-mutex.h>
33 #include <mono/utils/mono-counters.h>
37 #ifdef USE_INCLUDED_LIBGC
40 #define THREAD_LOCAL_ALLOC 1
41 #include "private/pthread_support.h"
44 #if defined(PLATFORM_MACOSX) && defined(HAVE_PTHREAD_GET_STACKADDR_NP)
45 void *pthread_get_stackaddr_np(pthread_t);
48 #define GC_NO_DESCRIPTOR ((gpointer)(0 | GC_DS_LENGTH))
49 /*Boehm max heap cannot be smaller than 16MB*/
50 #define MIN_BOEHM_MAX_HEAP_SIZE_IN_MB 16
51 #define MIN_BOEHM_MAX_HEAP_SIZE (MIN_BOEHM_MAX_HEAP_SIZE_IN_MB << 20)
53 static gboolean gc_initialized = FALSE;
54 static mono_mutex_t mono_gc_lock;
57 boehm_thread_register (MonoThreadInfo* info, void *baseptr);
59 boehm_thread_unregister (MonoThreadInfo *p);
61 register_test_toggleref_callback (void);
63 #define BOEHM_GC_BIT_FINALIZER_AWARE 1
64 static MonoGCFinalizerCallbacks fin_callbacks;
67 mono_gc_warning (char *msg, GC_word arg)
69 mono_trace (G_LOG_LEVEL_WARNING, MONO_TRACE_GC, msg, (unsigned long)arg);
73 mono_gc_base_init (void)
75 MonoThreadInfoCallbacks cb;
82 mono_counters_init ();
85 * Handle the case when we are called from a thread different from the main thread,
87 * FIXME: Move this to libgc where it belongs.
89 * we used to do this only when running on valgrind,
90 * but it happens also in other setups.
92 #if defined(HAVE_PTHREAD_GETATTR_NP) && defined(HAVE_PTHREAD_ATTR_GETSTACK) && !defined(__native_client__)
97 pthread_getattr_np (pthread_self (), &attr);
98 pthread_attr_getstack (&attr, &sstart, &size);
99 pthread_attr_destroy (&attr);
100 /*g_print ("stackbottom pth is: %p\n", (char*)sstart + size);*/
103 * The calculation above doesn't seem to work on ia64, also we need to set
104 * GC_register_stackbottom as well, but don't know how.
107 /* apparently with some linuxthreads implementations sstart can be NULL,
108 * fallback to the more imprecise method (bug# 78096).
111 GC_stackbottom = (char*)sstart + size;
114 gsize stack_bottom = (gsize)&dummy;
115 stack_bottom += 4095;
116 stack_bottom &= ~4095;
117 GC_stackbottom = (char*)stack_bottom;
121 #elif defined(HAVE_PTHREAD_GET_STACKSIZE_NP) && defined(HAVE_PTHREAD_GET_STACKADDR_NP)
122 GC_stackbottom = (char*)pthread_get_stackaddr_np (pthread_self ());
123 #elif defined(__OpenBSD__)
124 # include <pthread_np.h>
129 rslt = pthread_stackseg_np(pthread_self(), &ss);
130 g_assert (rslt == 0);
132 GC_stackbottom = (char*)ss.ss_sp;
134 #elif defined(__native_client__)
135 /* Do nothing, GC_stackbottom is set correctly in libgc */
139 gsize stack_bottom = (gsize)&dummy;
140 stack_bottom += 4095;
141 stack_bottom &= ~4095;
142 /*g_print ("stackbottom is: %p\n", (char*)stack_bottom);*/
143 GC_stackbottom = (char*)stack_bottom;
147 #if !defined(PLATFORM_ANDROID)
148 /* If GC_no_dls is set to true, GC_find_limit is not called. This causes a seg fault on Android. */
152 if ((env = g_getenv ("MONO_GC_DEBUG"))) {
153 char **opts = g_strsplit (env, ",", -1);
154 for (char **ptr = opts; ptr && *ptr; ptr ++) {
156 if (!strcmp (opt, "do-not-finalize")) {
158 } else if (!strcmp (opt, "log-finalizers")) {
167 GC_oom_fn = mono_gc_out_of_memory;
168 GC_set_warn_proc (mono_gc_warning);
169 GC_finalize_on_demand = 1;
170 GC_finalizer_notifier = mono_gc_finalize_notify;
172 #ifdef HAVE_GC_GCJ_MALLOC
173 GC_init_gcj_malloc (5, NULL);
176 #ifdef HAVE_GC_ALLOW_REGISTER_THREADS
177 GC_allow_register_threads();
180 if ((env = g_getenv ("MONO_GC_PARAMS"))) {
181 char **ptr, **opts = g_strsplit (env, ",", -1);
182 for (ptr = opts; *ptr; ++ptr) {
184 if (g_str_has_prefix (opt, "max-heap-size=")) {
187 opt = strchr (opt, '=') + 1;
188 if (*opt && mono_gc_parse_environment_string_extract_number (opt, &max_heap)) {
189 if (max_heap < MIN_BOEHM_MAX_HEAP_SIZE) {
190 fprintf (stderr, "max-heap-size must be at least %dMb.\n", MIN_BOEHM_MAX_HEAP_SIZE_IN_MB);
193 GC_set_max_heap_size (max_heap);
195 fprintf (stderr, "max-heap-size must be an integer.\n");
199 } else if (g_str_has_prefix (opt, "toggleref-test")) {
200 register_test_toggleref_callback ();
203 /* Could be a parameter for sgen */
205 fprintf (stderr, "MONO_GC_PARAMS must be a comma-delimited list of one or more of the following:\n");
206 fprintf (stderr, " max-heap-size=N (where N is an integer, possibly with a k, m or a g suffix)\n");
214 memset (&cb, 0, sizeof (cb));
215 cb.thread_register = boehm_thread_register;
216 cb.thread_unregister = boehm_thread_unregister;
217 cb.mono_method_is_critical = (gpointer)mono_runtime_is_critical_method;
219 cb.thread_exit = mono_gc_pthread_exit;
220 cb.mono_gc_pthread_create = (gpointer)mono_gc_pthread_create;
223 mono_threads_init (&cb, sizeof (MonoThreadInfo));
224 mono_mutex_init (&mono_gc_lock);
226 mono_thread_info_attach (&dummy);
228 mono_gc_enable_events ();
229 gc_initialized = TRUE;
234 * @generation: GC generation identifier
236 * Perform a garbage collection for the given generation, higher numbers
237 * mean usually older objects. Collecting a high-numbered generation
238 * implies collecting also the lower-numbered generations.
239 * The maximum value for @generation can be retrieved with a call to
240 * mono_gc_max_generation(), so this function is usually called as:
242 * mono_gc_collect (mono_gc_max_generation ());
245 mono_gc_collect (int generation)
247 #ifndef DISABLE_PERFCOUNTERS
248 mono_perfcounters->gc_induced++;
254 * mono_gc_max_generation:
256 * Get the maximum generation number used by the current garbage
257 * collector. The value will be 0 for the Boehm collector, 1 or more
258 * for the generational collectors.
260 * Returns: the maximum generation number.
263 mono_gc_max_generation (void)
269 * mono_gc_get_generation:
270 * @object: a managed object
272 * Get the garbage collector's generation that @object belongs to.
273 * Use this has a hint only.
275 * Returns: a garbage collector generation number
278 mono_gc_get_generation (MonoObject *object)
284 * mono_gc_collection_count:
285 * @generation: a GC generation number
287 * Get how many times a garbage collection has been performed
288 * for the given @generation number.
290 * Returns: the number of garbage collections
293 mono_gc_collection_count (int generation)
299 * mono_gc_add_memory_pressure:
300 * @value: amount of bytes
302 * Adjust the garbage collector's view of how many bytes of memory
303 * are indirectly referenced by managed objects (for example unmanaged
304 * memory holding image or other binary data).
305 * This is a hint only to the garbage collector algorithm.
306 * Note that negative amounts of @value will decrease the memory
310 mono_gc_add_memory_pressure (gint64 value)
315 * mono_gc_get_used_size:
317 * Get the approximate amount of memory used by managed objects.
319 * Returns: the amount of memory used in bytes
322 mono_gc_get_used_size (void)
324 return GC_get_heap_size () - GC_get_free_bytes ();
328 * mono_gc_get_heap_size:
330 * Get the amount of memory used by the garbage collector.
332 * Returns: the size of the heap in bytes
335 mono_gc_get_heap_size (void)
337 return GC_get_heap_size ();
341 mono_gc_is_gc_thread (void)
343 #if GC_VERSION_MAJOR >= 7
345 #elif defined(USE_INCLUDED_LIBGC)
346 return GC_thread_is_registered ();
352 extern int GC_thread_register_foreign (void *base_addr);
355 mono_gc_register_thread (void *baseptr)
357 return mono_thread_info_attach (baseptr) != NULL;
361 boehm_thread_register (MonoThreadInfo* info, void *baseptr)
363 #if GC_VERSION_MAJOR >= 7
364 struct GC_stack_base sb;
367 res = GC_get_stack_base (&sb);
368 if (res != GC_SUCCESS) {
369 sb.mem_base = baseptr;
371 /* Can't determine the register stack bounds */
372 g_error ("mono_gc_register_thread failed ().\n");
375 res = GC_register_my_thread (&sb);
376 if ((res != GC_SUCCESS) && (res != GC_DUPLICATE)) {
377 g_warning ("GC_register_my_thread () failed.\n");
382 if (mono_gc_is_gc_thread())
384 #if defined(USE_INCLUDED_LIBGC) && !defined(HOST_WIN32)
385 return GC_thread_register_foreign (baseptr) ? info : NULL;
393 boehm_thread_unregister (MonoThreadInfo *p)
395 MonoNativeThreadId tid;
397 tid = mono_thread_info_get_tid (p);
399 if (p->runtime_thread)
400 mono_threads_add_joinable_thread ((gpointer)tid);
404 mono_object_is_alive (MonoObject* o)
406 #ifdef USE_INCLUDED_LIBGC
407 return GC_is_marked ((gpointer)o);
414 mono_gc_walk_heap (int flags, MonoGCReferences callback, void *data)
419 #ifdef USE_INCLUDED_LIBGC
421 static gint64 gc_start_time;
424 on_gc_notification (GCEventType event)
426 MonoGCEvent e = (MonoGCEvent)event;
429 case MONO_GC_EVENT_PRE_STOP_WORLD:
430 MONO_GC_WORLD_STOP_BEGIN ();
431 mono_thread_info_suspend_lock ();
434 case MONO_GC_EVENT_POST_STOP_WORLD:
435 MONO_GC_WORLD_STOP_END ();
438 case MONO_GC_EVENT_PRE_START_WORLD:
439 MONO_GC_WORLD_RESTART_BEGIN (1);
442 case MONO_GC_EVENT_POST_START_WORLD:
443 MONO_GC_WORLD_RESTART_END (1);
444 mono_thread_info_suspend_unlock ();
447 case MONO_GC_EVENT_START:
449 #ifndef DISABLE_PERFCOUNTERS
450 if (mono_perfcounters)
451 mono_perfcounters->gc_collections0++;
453 gc_stats.major_gc_count ++;
454 gc_start_time = mono_100ns_ticks ();
457 case MONO_GC_EVENT_END:
459 #if defined(ENABLE_DTRACE) && defined(__sun__)
460 /* This works around a dtrace -G problem on Solaris.
461 Limit its actual use to when the probe is enabled. */
462 if (MONO_GC_END_ENABLED ())
466 #ifndef DISABLE_PERFCOUNTERS
467 if (mono_perfcounters) {
468 guint64 heap_size = GC_get_heap_size ();
469 guint64 used_size = heap_size - GC_get_free_bytes ();
470 mono_perfcounters->gc_total_bytes = used_size;
471 mono_perfcounters->gc_committed_bytes = heap_size;
472 mono_perfcounters->gc_reserved_bytes = heap_size;
473 mono_perfcounters->gc_gen0size = heap_size;
476 gc_stats.major_gc_time += mono_100ns_ticks () - gc_start_time;
477 mono_trace_message (MONO_TRACE_GC, "gc took %d usecs", (mono_100ns_ticks () - gc_start_time) / 10);
483 mono_profiler_gc_event (e, 0);
487 on_gc_heap_resize (size_t new_size)
489 guint64 heap_size = GC_get_heap_size ();
490 #ifndef DISABLE_PERFCOUNTERS
491 if (mono_perfcounters) {
492 mono_perfcounters->gc_committed_bytes = heap_size;
493 mono_perfcounters->gc_reserved_bytes = heap_size;
494 mono_perfcounters->gc_gen0size = heap_size;
497 mono_profiler_gc_heap_resize (new_size);
501 mono_gc_enable_events (void)
503 GC_notify_event = on_gc_notification;
504 GC_on_heap_resize = on_gc_heap_resize;
510 mono_gc_enable_events (void)
517 mono_gc_register_root (char *start, size_t size, void *descr)
519 /* for some strange reason, they want one extra byte on the end */
520 GC_add_roots (start, start + size + 1);
526 mono_gc_deregister_root (char* addr)
529 /* FIXME: libgc doesn't define this work win32 for some reason */
530 /* FIXME: No size info */
531 GC_remove_roots (addr, addr + sizeof (gpointer) + 1);
536 mono_gc_weak_link_add (void **link_addr, MonoObject *obj, gboolean track)
538 /* libgc requires that we use HIDE_POINTER... */
539 *link_addr = (void*)HIDE_POINTER (obj);
541 GC_REGISTER_LONG_LINK (link_addr, obj);
543 GC_GENERAL_REGISTER_DISAPPEARING_LINK (link_addr, obj);
547 mono_gc_weak_link_remove (void **link_addr, gboolean track)
550 GC_unregister_long_link (link_addr);
552 GC_unregister_disappearing_link (link_addr);
557 reveal_link (gpointer link_addr)
559 void **link_a = link_addr;
560 return REVEAL_POINTER (*link_a);
564 mono_gc_weak_link_get (void **link_addr)
566 MonoObject *obj = GC_call_with_alloc_lock (reveal_link, link_addr);
567 if (obj == (MonoObject *) -1)
573 mono_gc_make_descr_for_string (gsize *bitmap, int numbits)
575 return mono_gc_make_descr_from_bitmap (bitmap, numbits);
579 mono_gc_make_descr_for_object (gsize *bitmap, int numbits, size_t obj_size)
581 return mono_gc_make_descr_from_bitmap (bitmap, numbits);
585 mono_gc_make_descr_for_array (int vector, gsize *elem_bitmap, int numbits, size_t elem_size)
587 /* libgc has no usable support for arrays... */
588 return GC_NO_DESCRIPTOR;
592 mono_gc_make_descr_from_bitmap (gsize *bitmap, int numbits)
594 #ifdef HAVE_GC_GCJ_MALLOC
595 /* It seems there are issues when the bitmap doesn't fit: play it safe */
597 return GC_NO_DESCRIPTOR;
599 return (gpointer)GC_make_descriptor ((GC_bitmap)bitmap, numbits);
606 mono_gc_make_root_descr_all_refs (int numbits)
612 mono_gc_alloc_fixed (size_t size, void *descr)
614 /* To help track down typed allocation bugs */
618 if (count == atoi (g_getenv ("COUNT2")))
620 if (count > atoi (g_getenv ("COUNT2")))
621 return GC_MALLOC (size);
625 return GC_MALLOC_EXPLICITLY_TYPED (size, (GC_descr)descr);
627 return GC_MALLOC (size);
631 mono_gc_free_fixed (void* addr)
636 mono_gc_invoke_finalizers (void)
638 /* There is a bug in GC_invoke_finalizer () in versions <= 6.2alpha4:
639 * the 'mem_freed' variable is not initialized when there are no
640 * objects to finalize, which leads to strange behavior later on.
641 * The check is necessary to work around that bug.
643 if (GC_should_invoke_finalizers ())
644 return GC_invoke_finalizers ();
649 mono_gc_pending_finalizers (void)
651 return GC_should_invoke_finalizers ();
655 mono_gc_wbarrier_set_field (MonoObject *obj, gpointer field_ptr, MonoObject* value)
657 *(void**)field_ptr = value;
661 mono_gc_wbarrier_set_arrayref (MonoArray *arr, gpointer slot_ptr, MonoObject* value)
663 *(void**)slot_ptr = value;
667 mono_gc_wbarrier_arrayref_copy (gpointer dest_ptr, gpointer src_ptr, int count)
669 mono_gc_memmove_aligned (dest_ptr, src_ptr, count * sizeof (gpointer));
673 mono_gc_wbarrier_generic_store (gpointer ptr, MonoObject* value)
675 *(void**)ptr = value;
679 mono_gc_wbarrier_generic_store_atomic (gpointer ptr, MonoObject *value)
681 InterlockedWritePointer (ptr, value);
685 mono_gc_wbarrier_generic_nostore (gpointer ptr)
690 mono_gc_wbarrier_value_copy (gpointer dest, gpointer src, int count, MonoClass *klass)
692 mono_gc_memmove_atomic (dest, src, count * mono_class_value_size (klass, NULL));
696 mono_gc_wbarrier_object_copy (MonoObject* obj, MonoObject *src)
698 /* do not copy the sync state */
699 mono_gc_memmove_aligned ((char*)obj + sizeof (MonoObject), (char*)src + sizeof (MonoObject),
700 mono_object_class (obj)->instance_size - sizeof (MonoObject));
704 mono_gc_clear_domain (MonoDomain *domain)
709 mono_gc_get_suspend_signal (void)
711 #ifdef USE_INCLUDED_GC
712 return GC_get_suspend_signal ();
719 mono_gc_get_restart_signal (void)
721 #ifdef USE_INCLUDED_GC
722 return GC_get_restart_signal ();
728 #if defined(USE_INCLUDED_LIBGC) && defined(USE_COMPILER_TLS) && defined(__linux__) && (defined(__i386__) || defined(__x86_64__))
729 extern __thread MONO_TLS_FAST void* GC_thread_tls;
730 #include "metadata-internals.h"
736 while (!(v & (1 << i)))
743 ATYPE_FREEPTR_FOR_BOX,
751 create_allocator (int atype, int tls_key)
753 int index_var, bytes_var, my_fl_var, my_entry_var;
754 guint32 no_freelist_branch, not_small_enough_branch = 0;
755 guint32 size_overflow_branch = 0;
756 MonoMethodBuilder *mb;
758 MonoMethodSignature *csig;
759 AllocatorWrapperInfo *info;
761 if (atype == ATYPE_STRING) {
762 csig = mono_metadata_signature_alloc (mono_defaults.corlib, 2);
763 csig->ret = &mono_defaults.string_class->byval_arg;
764 csig->params [0] = &mono_defaults.int_class->byval_arg;
765 csig->params [1] = &mono_defaults.int32_class->byval_arg;
767 csig = mono_metadata_signature_alloc (mono_defaults.corlib, 2);
768 csig->ret = &mono_defaults.object_class->byval_arg;
769 csig->params [0] = &mono_defaults.int_class->byval_arg;
770 csig->params [1] = &mono_defaults.int32_class->byval_arg;
773 mb = mono_mb_new (mono_defaults.object_class, "Alloc", MONO_WRAPPER_ALLOC);
774 bytes_var = mono_mb_add_local (mb, &mono_defaults.int32_class->byval_arg);
775 if (atype == ATYPE_STRING) {
776 /* a string alloator method takes the args: (vtable, len) */
777 /* bytes = (offsetof (MonoString, chars) + ((len + 1) * 2)); */
778 mono_mb_emit_ldarg (mb, 1);
779 mono_mb_emit_icon (mb, 1);
780 mono_mb_emit_byte (mb, MONO_CEE_ADD);
781 mono_mb_emit_icon (mb, 1);
782 mono_mb_emit_byte (mb, MONO_CEE_SHL);
783 // sizeof (MonoString) might include padding
784 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoString, chars));
785 mono_mb_emit_byte (mb, MONO_CEE_ADD);
786 mono_mb_emit_stloc (mb, bytes_var);
788 mono_mb_emit_ldarg (mb, 1);
789 mono_mb_emit_stloc (mb, bytes_var);
792 /* this is needed for strings/arrays only as the other big types are never allocated with this method */
793 if (atype == ATYPE_STRING) {
795 /* if (!SMALL_ENOUGH (bytes)) jump slow_path;*/
796 mono_mb_emit_ldloc (mb, bytes_var);
797 mono_mb_emit_icon (mb, (NFREELISTS-1) * GRANULARITY);
798 not_small_enough_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BGT_UN_S);
799 /* check for overflow */
800 mono_mb_emit_ldloc (mb, bytes_var);
801 mono_mb_emit_icon (mb, sizeof (MonoString));
802 size_overflow_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLE_UN_S);
805 /* int index = INDEX_FROM_BYTES(bytes); */
806 index_var = mono_mb_add_local (mb, &mono_defaults.int32_class->byval_arg);
808 mono_mb_emit_ldloc (mb, bytes_var);
809 mono_mb_emit_icon (mb, GRANULARITY - 1);
810 mono_mb_emit_byte (mb, MONO_CEE_ADD);
811 mono_mb_emit_icon (mb, shift_amount (GRANULARITY));
812 mono_mb_emit_byte (mb, MONO_CEE_SHR_UN);
813 mono_mb_emit_icon (mb, shift_amount (sizeof (gpointer)));
814 mono_mb_emit_byte (mb, MONO_CEE_SHL);
815 /* index var is already adjusted into bytes */
816 mono_mb_emit_stloc (mb, index_var);
818 my_fl_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
819 my_entry_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
820 /* my_fl = ((GC_thread)tsd) -> ptrfree_freelists + index; */
821 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
822 mono_mb_emit_byte (mb, 0x0D); /* CEE_MONO_TLS */
823 mono_mb_emit_i4 (mb, tls_key);
824 if (atype == ATYPE_FREEPTR || atype == ATYPE_FREEPTR_FOR_BOX || atype == ATYPE_STRING)
825 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (struct GC_Thread_Rep, ptrfree_freelists));
826 else if (atype == ATYPE_NORMAL)
827 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (struct GC_Thread_Rep, normal_freelists));
828 else if (atype == ATYPE_GCJ)
829 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (struct GC_Thread_Rep, gcj_freelists));
831 g_assert_not_reached ();
832 mono_mb_emit_byte (mb, MONO_CEE_ADD);
833 mono_mb_emit_ldloc (mb, index_var);
834 mono_mb_emit_byte (mb, MONO_CEE_ADD);
835 mono_mb_emit_stloc (mb, my_fl_var);
837 /* my_entry = *my_fl; */
838 mono_mb_emit_ldloc (mb, my_fl_var);
839 mono_mb_emit_byte (mb, MONO_CEE_LDIND_I);
840 mono_mb_emit_stloc (mb, my_entry_var);
842 /* if (EXPECT((word)my_entry >= HBLKSIZE, 1)) { */
843 mono_mb_emit_ldloc (mb, my_entry_var);
844 mono_mb_emit_icon (mb, HBLKSIZE);
845 no_freelist_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLT_UN_S);
847 /* ptr_t next = obj_link(my_entry); *my_fl = next; */
848 mono_mb_emit_ldloc (mb, my_fl_var);
849 mono_mb_emit_ldloc (mb, my_entry_var);
850 mono_mb_emit_byte (mb, MONO_CEE_LDIND_I);
851 mono_mb_emit_byte (mb, MONO_CEE_STIND_I);
853 /* set the vtable and clear the words in the object */
854 mono_mb_emit_ldloc (mb, my_entry_var);
855 mono_mb_emit_ldarg (mb, 0);
856 mono_mb_emit_byte (mb, MONO_CEE_STIND_I);
858 if (atype == ATYPE_FREEPTR) {
859 int start_var, end_var, start_loop;
860 /* end = my_entry + bytes; start = my_entry + sizeof (gpointer);
862 start_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
863 end_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
864 mono_mb_emit_ldloc (mb, my_entry_var);
865 mono_mb_emit_ldloc (mb, bytes_var);
866 mono_mb_emit_byte (mb, MONO_CEE_ADD);
867 mono_mb_emit_stloc (mb, end_var);
868 mono_mb_emit_ldloc (mb, my_entry_var);
869 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoObject, synchronisation));
870 mono_mb_emit_byte (mb, MONO_CEE_ADD);
871 mono_mb_emit_stloc (mb, start_var);
875 * } while (start < end);
877 start_loop = mono_mb_get_label (mb);
878 mono_mb_emit_ldloc (mb, start_var);
879 mono_mb_emit_icon (mb, 0);
880 mono_mb_emit_byte (mb, MONO_CEE_STIND_I);
881 mono_mb_emit_ldloc (mb, start_var);
882 mono_mb_emit_icon (mb, sizeof (gpointer));
883 mono_mb_emit_byte (mb, MONO_CEE_ADD);
884 mono_mb_emit_stloc (mb, start_var);
886 mono_mb_emit_ldloc (mb, start_var);
887 mono_mb_emit_ldloc (mb, end_var);
888 mono_mb_emit_byte (mb, MONO_CEE_BLT_UN_S);
889 mono_mb_emit_byte (mb, start_loop - (mono_mb_get_label (mb) + 1));
890 } else if (atype == ATYPE_FREEPTR_FOR_BOX || atype == ATYPE_STRING) {
891 /* need to clear just the sync pointer */
892 mono_mb_emit_ldloc (mb, my_entry_var);
893 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoObject, synchronisation));
894 mono_mb_emit_byte (mb, MONO_CEE_ADD);
895 mono_mb_emit_icon (mb, 0);
896 mono_mb_emit_byte (mb, MONO_CEE_STIND_I);
899 if (atype == ATYPE_STRING) {
900 /* need to set length and clear the last char */
901 /* s->length = len; */
902 mono_mb_emit_ldloc (mb, my_entry_var);
903 mono_mb_emit_icon (mb, G_STRUCT_OFFSET (MonoString, length));
904 mono_mb_emit_byte (mb, MONO_CEE_ADD);
905 mono_mb_emit_ldarg (mb, 1);
906 mono_mb_emit_byte (mb, MONO_CEE_STIND_I4);
907 /* s->chars [len] = 0; */
908 mono_mb_emit_ldloc (mb, my_entry_var);
909 mono_mb_emit_ldloc (mb, bytes_var);
910 mono_mb_emit_icon (mb, 2);
911 mono_mb_emit_byte (mb, MONO_CEE_SUB);
912 mono_mb_emit_byte (mb, MONO_CEE_ADD);
913 mono_mb_emit_icon (mb, 0);
914 mono_mb_emit_byte (mb, MONO_CEE_STIND_I2);
917 /* return my_entry; */
918 mono_mb_emit_ldloc (mb, my_entry_var);
919 mono_mb_emit_byte (mb, MONO_CEE_RET);
921 mono_mb_patch_short_branch (mb, no_freelist_branch);
922 if (not_small_enough_branch > 0)
923 mono_mb_patch_short_branch (mb, not_small_enough_branch);
924 if (size_overflow_branch > 0)
925 mono_mb_patch_short_branch (mb, size_overflow_branch);
926 /* the slow path: we just call back into the runtime */
927 if (atype == ATYPE_STRING) {
928 mono_mb_emit_ldarg (mb, 1);
929 mono_mb_emit_icall (mb, mono_string_alloc);
931 mono_mb_emit_ldarg (mb, 0);
932 mono_mb_emit_icall (mb, mono_object_new_specific);
935 mono_mb_emit_byte (mb, MONO_CEE_RET);
937 res = mono_mb_create_method (mb, csig, 8);
939 mono_method_get_header (res)->init_locals = FALSE;
941 info = mono_image_alloc0 (mono_defaults.corlib, sizeof (AllocatorWrapperInfo));
942 info->gc_name = "boehm";
943 info->alloc_type = atype;
944 mono_marshal_set_wrapper_info (res, info);
949 static MonoMethod* alloc_method_cache [ATYPE_NUM];
951 static G_GNUC_UNUSED gboolean
952 mono_gc_is_critical_method (MonoMethod *method)
956 for (i = 0; i < ATYPE_NUM; ++i)
957 if (method == alloc_method_cache [i])
964 * If possible, generate a managed method that can quickly allocate objects in class
965 * @klass. The method will typically have an thread-local inline allocation sequence.
966 * The signature of the called method is:
967 * object allocate (MonoVTable *vtable)
968 * Some of the logic here is similar to mono_class_get_allocation_ftn () i object.c,
970 * The thread local alloc logic is taken from libgc/pthread_support.c.
974 mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size)
978 MONO_THREAD_VAR_OFFSET (GC_thread_tls, offset);
980 /*g_print ("thread tls: %d\n", offset);*/
983 if (!SMALL_ENOUGH (klass->instance_size))
985 if (mono_class_has_finalizer (klass) || mono_class_is_marshalbyref (klass) || (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS))
989 if (mono_class_is_open_constructed_type (&klass->byval_arg))
991 if (klass->byval_arg.type == MONO_TYPE_STRING) {
992 atype = ATYPE_STRING;
993 } else if (!klass->has_references) {
995 atype = ATYPE_FREEPTR_FOR_BOX;
997 atype = ATYPE_FREEPTR;
1001 * disabled because we currently do a runtime choice anyway, to
1002 * deal with multiple appdomains.
1003 if (vtable->gc_descr != GC_NO_DESCRIPTOR)
1006 atype = ATYPE_NORMAL;
1009 return mono_gc_get_managed_allocator_by_type (atype);
1013 mono_gc_get_managed_array_allocator (MonoClass *klass)
1019 * mono_gc_get_managed_allocator_by_type:
1021 * Return a managed allocator method corresponding to allocator type ATYPE.
1024 mono_gc_get_managed_allocator_by_type (int atype)
1028 MONO_THREAD_VAR_OFFSET (GC_thread_tls, offset);
1030 mono_tls_key_set_offset (TLS_KEY_BOEHM_GC_THREAD, offset);
1032 res = alloc_method_cache [atype];
1036 res = create_allocator (atype, TLS_KEY_BOEHM_GC_THREAD);
1037 mono_mutex_lock (&mono_gc_lock);
1038 if (alloc_method_cache [atype]) {
1039 mono_free_method (res);
1040 res = alloc_method_cache [atype];
1042 mono_memory_barrier ();
1043 alloc_method_cache [atype] = res;
1045 mono_mutex_unlock (&mono_gc_lock);
1050 mono_gc_get_managed_allocator_types (void)
1056 mono_gc_get_write_barrier (void)
1058 g_assert_not_reached ();
1064 static G_GNUC_UNUSED gboolean
1065 mono_gc_is_critical_method (MonoMethod *method)
1071 mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size)
1077 mono_gc_get_managed_array_allocator (MonoClass *klass)
1083 mono_gc_get_managed_allocator_by_type (int atype)
1089 mono_gc_get_managed_allocator_types (void)
1095 mono_gc_get_write_barrier (void)
1097 g_assert_not_reached ();
1104 mono_gc_get_specific_write_barrier (gboolean is_concurrent)
1106 g_assert_not_reached ();
1111 mono_gc_get_aligned_size_for_allocator (int size)
1117 mono_gc_get_gc_name (void)
1123 mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data)
1125 return GC_call_with_alloc_lock (func, data);
1129 mono_gc_get_description (void)
1131 return g_strdup (DEFAULT_GC_NAME);
1135 mono_gc_set_desktop_mode (void)
1141 mono_gc_is_moving (void)
1147 mono_gc_is_disabled (void)
1149 if (GC_dont_gc || g_getenv ("GC_DONT_GC"))
1156 mono_gc_wbarrier_value_copy_bitmap (gpointer _dest, gpointer _src, int size, unsigned bitmap)
1158 g_assert_not_reached ();
1163 mono_gc_get_card_table (int *shift_bits, gpointer *card_mask)
1165 g_assert_not_reached ();
1170 mono_gc_card_table_nursery_check (void)
1172 g_assert_not_reached ();
1177 mono_gc_get_nursery (int *shift_bits, size_t *size)
1183 mono_gc_set_current_thread_appdomain (MonoDomain *domain)
1188 mono_gc_precise_stack_mark_enabled (void)
1194 mono_gc_get_logfile (void)
1200 mono_gc_conservatively_scan_area (void *start, void *end)
1202 g_assert_not_reached ();
1206 mono_gc_scan_object (void *obj, void *gc_data)
1208 g_assert_not_reached ();
1213 mono_gc_get_bitmap_for_descr (void *descr, int *numbits)
1215 g_assert_not_reached ();
1220 mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks)
1225 mono_gc_set_stack_end (void *stack_end)
1229 void mono_gc_set_skip_thread (gboolean value)
1234 mono_gc_register_for_finalization (MonoObject *obj, void *user_data)
1239 /* This assertion is not valid when GC_DEBUG is defined */
1240 g_assert (GC_base (obj) == (char*)obj - offset);
1243 GC_REGISTER_FINALIZER_NO_ORDER ((char*)obj - offset, user_data, GUINT_TO_POINTER (offset), NULL, NULL);
1247 * These will call the redefined versions in libgc.
1253 mono_gc_pthread_create (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg)
1255 return pthread_create (new_thread, attr, start_routine, arg);
1259 mono_gc_pthread_join (pthread_t thread, void **retval)
1261 return pthread_join (thread, retval);
1265 mono_gc_pthread_detach (pthread_t thread)
1267 return pthread_detach (thread);
1271 mono_gc_pthread_exit (void *retval)
1273 pthread_exit (retval);
1274 g_assert_not_reached ();
1280 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved)
1282 #ifdef USE_INCLUDED_LIBGC
1283 return GC_DllMain (module_handle, reason, reserved);
1291 mono_gc_get_vtable_bits (MonoClass *class)
1293 if (fin_callbacks.is_class_finalization_aware) {
1294 if (fin_callbacks.is_class_finalization_aware (class))
1295 return BOEHM_GC_BIT_FINALIZER_AWARE;
1301 * mono_gc_register_altstack:
1303 * Register the dimensions of the normal stack and altstack with the collector.
1304 * Currently, STACK/STACK_SIZE is only used when the thread is suspended while it is on an altstack.
1307 mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size)
1309 #ifdef USE_INCLUDED_LIBGC
1310 GC_register_altstack (stack, stack_size, altstack, altstack_size);
1315 mono_gc_get_los_limit (void)
1321 mono_gc_set_string_length (MonoString *str, gint32 new_length)
1323 mono_unichar2 *new_end = str->chars + new_length;
1325 /* zero the discarded string. This null-delimits the string and allows
1326 * the space to be reclaimed by SGen. */
1328 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2));
1329 str->length = new_length;
1333 mono_gc_user_markers_supported (void)
1339 mono_gc_make_root_descr_user (MonoGCRootMarkFunc marker)
1341 g_assert_not_reached ();
1346 mono_gc_set_allow_synchronous_major (gboolean flag)
1350 /* Toggleref support */
1353 mono_gc_toggleref_add (MonoObject *object, mono_bool strong_ref)
1355 GC_toggleref_add ((GC_PTR)object, (int)strong_ref);
1359 mono_gc_toggleref_register_callback (MonoToggleRefStatus (*proccess_toggleref) (MonoObject *obj))
1361 GC_toggleref_register_callback ((int (*) (GC_PTR obj)) proccess_toggleref);
1364 /* Test support code */
1366 static MonoToggleRefStatus
1367 test_toggleref_callback (MonoObject *obj)
1369 static MonoClassField *mono_toggleref_test_field;
1370 int status = MONO_TOGGLE_REF_DROP;
1372 if (!mono_toggleref_test_field) {
1373 mono_toggleref_test_field = mono_class_get_field_from_name (mono_object_get_class (obj), "__test");
1374 g_assert (mono_toggleref_test_field);
1377 mono_field_get_value (obj, mono_toggleref_test_field, &status);
1378 printf ("toggleref-cb obj %d\n", status);
1383 register_test_toggleref_callback (void)
1385 mono_gc_toggleref_register_callback (test_toggleref_callback);
1389 is_finalization_aware (MonoObject *obj)
1391 MonoVTable *vt = obj->vtable;
1392 return (vt->gc_bits & BOEHM_GC_BIT_FINALIZER_AWARE) == BOEHM_GC_BIT_FINALIZER_AWARE;
1396 fin_notifier (MonoObject *obj)
1398 if (is_finalization_aware (obj))
1399 fin_callbacks.object_queued_for_finalization (obj);
1403 mono_gc_register_finalizer_callbacks (MonoGCFinalizerCallbacks *callbacks)
1405 if (callbacks->version != MONO_GC_FINALIZER_EXTENSION_VERSION)
1406 g_error ("Invalid finalizer callback version. Expected %d but got %d\n", MONO_GC_FINALIZER_EXTENSION_VERSION, callbacks->version);
1408 fin_callbacks = *callbacks;
1410 GC_set_finalizer_notify_proc ((void (*) (GC_PTR))fin_notifier);
1413 #endif /* no Boehm GC */