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GC bridge: Move bridge-require-precise-merge to MONO_GC_PARAMS
[mono-project.git] / mono / metadata / sgen-mono.c
blobf80cc3603191c59483fa1f7e1e82702b6ac9898e
1 /*
2 * sgen-mono.c: SGen features specific to Mono.
3 *
4 * Copyright (C) 2014 Xamarin Inc
5 *
6 * Licensed under the MIT license. See LICENSE file in the project root for full license information.
7 */
8
9 #include "config.h"
10 #ifdef HAVE_SGEN_GC
11
12 #include "sgen/sgen-gc.h"
13 #include "sgen/sgen-protocol.h"
14 #include "metadata/monitor.h"
15 #include "sgen/sgen-layout-stats.h"
16 #include "sgen/sgen-client.h"
17 #include "sgen/sgen-cardtable.h"
18 #include "sgen/sgen-pinning.h"
19 #include "metadata/marshal.h"
20 #include "metadata/method-builder.h"
21 #include "metadata/abi-details.h"
22 #include "metadata/mono-gc.h"
23 #include "metadata/runtime.h"
24 #include "metadata/sgen-bridge-internals.h"
25 #include "metadata/gc-internals.h"
26 #include "metadata/handle.h"
27 #include "utils/mono-memory-model.h"
28 #include "utils/mono-logger-internals.h"
29 #include "utils/mono-threads-coop.h"
30 #include "sgen/sgen-thread-pool.h"
31
32 #ifdef HEAVY_STATISTICS
33 static guint64 stat_wbarrier_set_arrayref = 0;
34 static guint64 stat_wbarrier_value_copy = 0;
35 static guint64 stat_wbarrier_object_copy = 0;
36
37 static guint64 los_marked_cards;
38 static guint64 los_array_cards;
39 static guint64 los_array_remsets;
40 #endif
41
42 /* If set, mark stacks conservatively, even if precise marking is possible */
43 static gboolean conservative_stack_mark = FALSE;
44 /* If set, check that there are no references to the domain left at domain unload */
45 gboolean sgen_mono_xdomain_checks = FALSE;
46
47 /* Functions supplied by the runtime to be called by the GC */
48 static MonoGCCallbacks gc_callbacks;
49
50 #ifdef HAVE_KW_THREAD
51 __thread SgenThreadInfo *sgen_thread_info;
52 #else
53 MonoNativeTlsKey thread_info_key;
54 #endif
55
56 #define ALIGN_TO(val,align) ((((guint64)val) + ((align) - 1)) & ~((align) - 1))
57
58 #define OPDEF(a,b,c,d,e,f,g,h,i,j) \
59 a = i,
60
61 enum {
62 #include "mono/cil/opcode.def"
63 CEE_LAST
64 };
65
66 #undef OPDEF
67
68 /*
69 * Write barriers
70 */
71
72 static gboolean
73 ptr_on_stack (void *ptr)
74 {
75 gpointer stack_start = &stack_start;
76 SgenThreadInfo *info = mono_thread_info_current ();
77
78 if (ptr >= stack_start && ptr < (gpointer)info->client_info.stack_end)
79 return TRUE;
80 return FALSE;
81 }
82
83 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
84 #undef HANDLE_PTR
85 #define HANDLE_PTR(ptr,obj) do { \
86 gpointer o = *(gpointer*)(ptr); \
87 if ((o)) { \
88 gpointer d = ((char*)dest) + ((char*)(ptr) - (char*)(obj)); \
89 binary_protocol_wbarrier (d, o, (gpointer) SGEN_LOAD_VTABLE (o)); \
90 } \
91 } while (0)
92
93 static void
94 scan_object_for_binary_protocol_copy_wbarrier (gpointer dest, char *start, mword desc)
95 {
96 #define SCAN_OBJECT_NOVTABLE
97 #include "sgen/sgen-scan-object.h"
98 }
99 #endif
100
101 void
102 mono_gc_wbarrier_value_copy (gpointer dest, gpointer src, int count, MonoClass *klass)
103 {
104 HEAVY_STAT (++stat_wbarrier_value_copy);
105 g_assert (klass->valuetype);
106
107 SGEN_LOG (8, "Adding value remset at %p, count %d, descr %p for class %s (%p)", dest, count, (gpointer)klass->gc_descr, klass->name, klass);
108
109 if (sgen_ptr_in_nursery (dest) || ptr_on_stack (dest) || !sgen_gc_descr_has_references ((mword)klass->gc_descr)) {
110 size_t element_size = mono_class_value_size (klass, NULL);
111 size_t size = count * element_size;
112 mono_gc_memmove_atomic (dest, src, size);
113 return;
114 }
115
116 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
117 if (binary_protocol_is_heavy_enabled ()) {
118 size_t element_size = mono_class_value_size (klass, NULL);
119 int i;
120 for (i = 0; i < count; ++i) {
121 scan_object_for_binary_protocol_copy_wbarrier ((char*)dest + i * element_size,
122 (char*)src + i * element_size - sizeof (MonoObject),
123 (mword) klass->gc_descr);
124 }
125 }
126 #endif
127
128 sgen_get_remset ()->wbarrier_value_copy (dest, src, count, mono_class_value_size (klass, NULL));
129 }
130
131 /**
132 * mono_gc_wbarrier_object_copy:
133 *
134 * Write barrier to call when obj is the result of a clone or copy of an object.
135 */
136 void
137 mono_gc_wbarrier_object_copy (MonoObject* obj, MonoObject *src)
138 {
139 int size;
140
141 HEAVY_STAT (++stat_wbarrier_object_copy);
142
143 SGEN_ASSERT (6, !ptr_on_stack (obj), "Why is this called for a non-reference type?");
144 if (sgen_ptr_in_nursery (obj) || !SGEN_OBJECT_HAS_REFERENCES (src)) {
145 size = mono_object_class (obj)->instance_size;
146 mono_gc_memmove_aligned ((char*)obj + sizeof (MonoObject), (char*)src + sizeof (MonoObject),
147 size - sizeof (MonoObject));
148 return;
149 }
150
151 #ifdef SGEN_HEAVY_BINARY_PROTOCOL
152 if (binary_protocol_is_heavy_enabled ())
153 scan_object_for_binary_protocol_copy_wbarrier (obj, (char*)src, (mword) src->vtable->gc_descr);
154 #endif
155
156 sgen_get_remset ()->wbarrier_object_copy (obj, src);
157 }
158
159 void
160 mono_gc_wbarrier_set_arrayref (MonoArray *arr, gpointer slot_ptr, MonoObject* value)
161 {
162 HEAVY_STAT (++stat_wbarrier_set_arrayref);
163 if (sgen_ptr_in_nursery (slot_ptr)) {
164 *(void**)slot_ptr = value;
165 return;
166 }
167 SGEN_LOG (8, "Adding remset at %p", slot_ptr);
168 if (value)
169 binary_protocol_wbarrier (slot_ptr, value, value->vtable);
170
171 sgen_get_remset ()->wbarrier_set_field ((GCObject*)arr, slot_ptr, value);
172 }
173
174 void
175 mono_gc_wbarrier_set_field (MonoObject *obj, gpointer field_ptr, MonoObject* value)
176 {
177 mono_gc_wbarrier_set_arrayref ((MonoArray*)obj, field_ptr, value);
178 }
179
180 void
181 mono_gc_wbarrier_value_copy_bitmap (gpointer _dest, gpointer _src, int size, unsigned bitmap)
182 {
183 sgen_wbarrier_value_copy_bitmap (_dest, _src, size, bitmap);
184 }
185
186 static MonoMethod *write_barrier_conc_method;
187 static MonoMethod *write_barrier_noconc_method;
188
189 gboolean
190 sgen_is_critical_method (MonoMethod *method)
191 {
192 return (method == write_barrier_conc_method || method == write_barrier_noconc_method || sgen_is_managed_allocator (method));
193 }
194
195 gboolean
196 sgen_has_critical_method (void)
197 {
198 return write_barrier_conc_method || write_barrier_noconc_method || sgen_has_managed_allocator ();
199 }
200
201 #ifndef DISABLE_JIT
202
203 static void
204 emit_nursery_check (MonoMethodBuilder *mb, int *nursery_check_return_labels, gboolean is_concurrent)
205 {
206 int shifted_nursery_start = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
207
208 memset (nursery_check_return_labels, 0, sizeof (int) * 2);
209 // if (ptr_in_nursery (ptr)) return;
210 /*
211 * Masking out the bits might be faster, but we would have to use 64 bit
212 * immediates, which might be slower.
213 */
214 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
215 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_START);
216 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
217 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
218 mono_mb_emit_byte (mb, CEE_SHR_UN);
219 mono_mb_emit_stloc (mb, shifted_nursery_start);
220
221 mono_mb_emit_ldarg (mb, 0);
222 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
223 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
224 mono_mb_emit_byte (mb, CEE_SHR_UN);
225 mono_mb_emit_ldloc (mb, shifted_nursery_start);
226 nursery_check_return_labels [0] = mono_mb_emit_branch (mb, CEE_BEQ);
227
228 if (!is_concurrent) {
229 // if (!ptr_in_nursery (*ptr)) return;
230 mono_mb_emit_ldarg (mb, 0);
231 mono_mb_emit_byte (mb, CEE_LDIND_I);
232 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
233 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_NURSERY_BITS);
234 mono_mb_emit_byte (mb, CEE_SHR_UN);
235 mono_mb_emit_ldloc (mb, shifted_nursery_start);
236 nursery_check_return_labels [1] = mono_mb_emit_branch (mb, CEE_BNE_UN);
237 }
238 }
239 #endif
240
241 MonoMethod*
242 mono_gc_get_specific_write_barrier (gboolean is_concurrent)
243 {
244 MonoMethod *res;
245 MonoMethodBuilder *mb;
246 MonoMethodSignature *sig;
247 MonoMethod **write_barrier_method_addr;
248 WrapperInfo *info;
249 #ifdef MANAGED_WBARRIER
250 int i, nursery_check_labels [2];
251 #endif
252
253 // FIXME: Maybe create a separate version for ctors (the branch would be
254 // correctly predicted more times)
255 if (is_concurrent)
256 write_barrier_method_addr = &write_barrier_conc_method;
257 else
258 write_barrier_method_addr = &write_barrier_noconc_method;
259
260 if (*write_barrier_method_addr)
261 return *write_barrier_method_addr;
262
263 /* Create the IL version of mono_gc_barrier_generic_store () */
264 sig = mono_metadata_signature_alloc (mono_defaults.corlib, 1);
265 sig->ret = &mono_defaults.void_class->byval_arg;
266 sig->params [0] = &mono_defaults.int_class->byval_arg;
267
268 if (is_concurrent)
269 mb = mono_mb_new (mono_defaults.object_class, "wbarrier_conc", MONO_WRAPPER_WRITE_BARRIER);
270 else
271 mb = mono_mb_new (mono_defaults.object_class, "wbarrier_noconc", MONO_WRAPPER_WRITE_BARRIER);
272
273 #ifndef DISABLE_JIT
274 #ifdef MANAGED_WBARRIER
275 emit_nursery_check (mb, nursery_check_labels, is_concurrent);
276 /*
277 addr = sgen_cardtable + ((address >> CARD_BITS) & CARD_MASK)
278 *addr = 1;
279
280 sgen_cardtable:
281 LDC_PTR sgen_cardtable
282
283 address >> CARD_BITS
284 LDARG_0
285 LDC_I4 CARD_BITS
286 SHR_UN
287 if (SGEN_HAVE_OVERLAPPING_CARDS) {
288 LDC_PTR card_table_mask
289 AND
290 }
291 AND
292 ldc_i4_1
293 stind_i1
294 */
295 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
296 mono_mb_emit_byte (mb, CEE_MONO_LDPTR_CARD_TABLE);
297 mono_mb_emit_ldarg (mb, 0);
298 mono_mb_emit_icon (mb, CARD_BITS);
299 mono_mb_emit_byte (mb, CEE_SHR_UN);
300 mono_mb_emit_byte (mb, CEE_CONV_I);
301 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
302 #if SIZEOF_VOID_P == 8
303 mono_mb_emit_icon8 (mb, CARD_MASK);
304 #else
305 mono_mb_emit_icon (mb, CARD_MASK);
306 #endif
307 mono_mb_emit_byte (mb, CEE_CONV_I);
308 mono_mb_emit_byte (mb, CEE_AND);
309 #endif
310 mono_mb_emit_byte (mb, CEE_ADD);
311 mono_mb_emit_icon (mb, 1);
312 mono_mb_emit_byte (mb, CEE_STIND_I1);
313
314 // return;
315 for (i = 0; i < 2; ++i) {
316 if (nursery_check_labels [i])
317 mono_mb_patch_branch (mb, nursery_check_labels [i]);
318 }
319 mono_mb_emit_byte (mb, CEE_RET);
320 #else
321 mono_mb_emit_ldarg (mb, 0);
322 mono_mb_emit_icall (mb, mono_gc_wbarrier_generic_nostore);
323 mono_mb_emit_byte (mb, CEE_RET);
324 #endif
325 #endif
326 res = mono_mb_create_method (mb, sig, 16);
327 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
328 mono_marshal_set_wrapper_info (res, info);
329 mono_mb_free (mb);
330
331 LOCK_GC;
332 if (*write_barrier_method_addr) {
333 /* Already created */
334 mono_free_method (res);
335 } else {
336 /* double-checked locking */
337 mono_memory_barrier ();
338 *write_barrier_method_addr = res;
339 }
340 UNLOCK_GC;
341
342 return *write_barrier_method_addr;
343 }
344
345 MonoMethod*
346 mono_gc_get_write_barrier (void)
347 {
348 return mono_gc_get_specific_write_barrier (major_collector.is_concurrent);
349 }
350
351 /*
352 * Dummy filler objects
353 */
354
355 /* Vtable of the objects used to fill out nursery fragments before a collection */
356 static GCVTable array_fill_vtable;
357
358 static GCVTable
359 get_array_fill_vtable (void)
360 {
361 if (!array_fill_vtable) {
362 static MonoClass klass;
363 static char _vtable[sizeof(MonoVTable)+8];
364 MonoVTable* vtable = (MonoVTable*) ALIGN_TO((mword)_vtable, 8);
365 gsize bmap;
366
367 MonoDomain *domain = mono_get_root_domain ();
368 g_assert (domain);
369
370 klass.element_class = mono_defaults.byte_class;
371 klass.rank = 1;
372 klass.instance_size = MONO_SIZEOF_MONO_ARRAY;
373 klass.sizes.element_size = 1;
374 klass.name = "array_filler_type";
375
376 vtable->klass = &klass;
377 bmap = 0;
378 vtable->gc_descr = mono_gc_make_descr_for_array (TRUE, &bmap, 0, 1);
379 vtable->rank = 1;
380
381 array_fill_vtable = vtable;
382 }
383 return array_fill_vtable;
384 }
385
386 gboolean
387 sgen_client_array_fill_range (char *start, size_t size)
388 {
389 MonoArray *o;
390
391 if (size < MONO_SIZEOF_MONO_ARRAY) {
392 memset (start, 0, size);
393 return FALSE;
394 }
395
396 o = (MonoArray*)start;
397 o->obj.vtable = (MonoVTable*)get_array_fill_vtable ();
398 /* Mark this as not a real object */
399 o->obj.synchronisation = (MonoThreadsSync *)GINT_TO_POINTER (-1);
400 o->bounds = NULL;
401 o->max_length = (mono_array_size_t)(size - MONO_SIZEOF_MONO_ARRAY);
402
403 return TRUE;
404 }
405
406 void
407 sgen_client_zero_array_fill_header (void *p, size_t size)
408 {
409 if (size >= MONO_SIZEOF_MONO_ARRAY) {
410 memset (p, 0, MONO_SIZEOF_MONO_ARRAY);
411 } else {
412 static guint8 zeros [MONO_SIZEOF_MONO_ARRAY];
413
414 SGEN_ASSERT (0, !memcmp (p, zeros, size), "TLAB segment must be zeroed out.");
415 }
416 }
417
418 /*
419 * Finalization
420 */
421
422 static MonoGCFinalizerCallbacks fin_callbacks;
423
424 guint
425 mono_gc_get_vtable_bits (MonoClass *klass)
426 {
427 guint res = 0;
428 /* FIXME move this to the bridge code */
429 if (sgen_need_bridge_processing ()) {
430 switch (sgen_bridge_class_kind (klass)) {
431 case GC_BRIDGE_TRANSPARENT_BRIDGE_CLASS:
432 case GC_BRIDGE_OPAQUE_BRIDGE_CLASS:
433 res = SGEN_GC_BIT_BRIDGE_OBJECT;
434 break;
435 case GC_BRIDGE_OPAQUE_CLASS:
436 res = SGEN_GC_BIT_BRIDGE_OPAQUE_OBJECT;
437 break;
438 case GC_BRIDGE_TRANSPARENT_CLASS:
439 break;
440 }
441 }
442 if (fin_callbacks.is_class_finalization_aware) {
443 if (fin_callbacks.is_class_finalization_aware (klass))
444 res |= SGEN_GC_BIT_FINALIZER_AWARE;
445 }
446 return res;
447 }
448
449 static gboolean
450 is_finalization_aware (MonoObject *obj)
451 {
452 MonoVTable *vt = SGEN_LOAD_VTABLE (obj);
453 return (vt->gc_bits & SGEN_GC_BIT_FINALIZER_AWARE) == SGEN_GC_BIT_FINALIZER_AWARE;
454 }
455
456 void
457 sgen_client_object_queued_for_finalization (GCObject *obj)
458 {
459 if (fin_callbacks.object_queued_for_finalization && is_finalization_aware (obj))
460 fin_callbacks.object_queued_for_finalization (obj);
461
462 #ifdef ENABLE_DTRACE
463 if (G_UNLIKELY (MONO_GC_FINALIZE_ENQUEUE_ENABLED ())) {
464 int gen = sgen_ptr_in_nursery (obj) ? GENERATION_NURSERY : GENERATION_OLD;
465 GCVTable vt = SGEN_LOAD_VTABLE (obj);
466 MONO_GC_FINALIZE_ENQUEUE ((mword)obj, sgen_safe_object_get_size (obj),
467 sgen_client_vtable_get_namespace (vt), sgen_client_vtable_get_name (vt), gen,
468 sgen_client_object_has_critical_finalizer (obj));
469 }
470 #endif
471 }
472
473 void
474 mono_gc_register_finalizer_callbacks (MonoGCFinalizerCallbacks *callbacks)
475 {
476 if (callbacks->version != MONO_GC_FINALIZER_EXTENSION_VERSION)
477 g_error ("Invalid finalizer callback version. Expected %d but got %d\n", MONO_GC_FINALIZER_EXTENSION_VERSION, callbacks->version);
478
479 fin_callbacks = *callbacks;
480 }
481
482 void
483 sgen_client_run_finalize (MonoObject *obj)
484 {
485 mono_gc_run_finalize (obj, NULL);
486 }
487
488 int
489 mono_gc_invoke_finalizers (void)
490 {
491 return sgen_gc_invoke_finalizers ();
492 }
493
494 gboolean
495 mono_gc_pending_finalizers (void)
496 {
497 return sgen_have_pending_finalizers ();
498 }
499
500 void
501 sgen_client_finalize_notify (void)
502 {
503 mono_gc_finalize_notify ();
504 }
505
506 void
507 mono_gc_register_for_finalization (MonoObject *obj, void *user_data)
508 {
509 sgen_object_register_for_finalization (obj, user_data);
510 }
511
512 static gboolean
513 object_in_domain_predicate (MonoObject *obj, void *user_data)
514 {
515 MonoDomain *domain = (MonoDomain *)user_data;
516 if (mono_object_domain (obj) == domain) {
517 SGEN_LOG (5, "Unregistering finalizer for object: %p (%s)", obj, sgen_client_vtable_get_name (SGEN_LOAD_VTABLE (obj)));
518 return TRUE;
519 }
520 return FALSE;
521 }
522
523 /**
524 * mono_gc_finalizers_for_domain:
525 * @domain: the unloading appdomain
526 * @out_array: output array
527 * @out_size: size of output array
528 *
529 * Enqueue for finalization all objects that belong to the unloading appdomain @domain
530 * @suspend is used for early termination of the enqueuing process.
531 */
532 void
533 mono_gc_finalize_domain (MonoDomain *domain)
534 {
535 sgen_finalize_if (object_in_domain_predicate, domain);
536 }
537
538 void
539 mono_gc_suspend_finalizers (void)
540 {
541 sgen_set_suspend_finalizers ();
542 }
543
544 /*
545 * Ephemerons
546 */
547
548 typedef struct _EphemeronLinkNode EphemeronLinkNode;
549
550 struct _EphemeronLinkNode {
551 EphemeronLinkNode *next;
552 MonoArray *array;
553 };
554
555 typedef struct {
556 GCObject *key;
557 GCObject *value;
558 } Ephemeron;
559
560 static EphemeronLinkNode *ephemeron_list;
561
562 /* LOCKING: requires that the GC lock is held */
563 static void
564 null_ephemerons_for_domain (MonoDomain *domain)
565 {
566 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
567
568 while (current) {
569 MonoObject *object = (MonoObject*)current->array;
570
571 if (object)
572 SGEN_ASSERT (0, object->vtable, "Can't have objects without vtables.");
573
574 if (object && object->vtable->domain == domain) {
575 EphemeronLinkNode *tmp = current;
576
577 if (prev)
578 prev->next = current->next;
579 else
580 ephemeron_list = current->next;
581
582 current = current->next;
583 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
584 } else {
585 prev = current;
586 current = current->next;
587 }
588 }
589 }
590
591 /* LOCKING: requires that the GC lock is held */
592 void
593 sgen_client_clear_unreachable_ephemerons (ScanCopyContext ctx)
594 {
595 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
596 SgenGrayQueue *queue = ctx.queue;
597 EphemeronLinkNode *current = ephemeron_list, *prev = NULL;
598 Ephemeron *cur, *array_end;
599 GCObject *tombstone;
600
601 while (current) {
602 MonoArray *array = current->array;
603
604 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
605 EphemeronLinkNode *tmp = current;
606
607 SGEN_LOG (5, "Dead Ephemeron array at %p", array);
608
609 if (prev)
610 prev->next = current->next;
611 else
612 ephemeron_list = current->next;
613
614 current = current->next;
615 sgen_free_internal (tmp, INTERNAL_MEM_EPHEMERON_LINK);
616
617 continue;
618 }
619
620 copy_func ((GCObject**)&array, queue);
621 current->array = array;
622
623 SGEN_LOG (5, "Clearing unreachable entries for ephemeron array at %p", array);
624
625 cur = mono_array_addr (array, Ephemeron, 0);
626 array_end = cur + mono_array_length_fast (array);
627 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
628
629 for (; cur < array_end; ++cur) {
630 GCObject *key = cur->key;
631
632 if (!key || key == tombstone)
633 continue;
634
635 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
636 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
637 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
638
639 if (!sgen_is_object_alive_for_current_gen (key)) {
640 cur->key = tombstone;
641 cur->value = NULL;
642 continue;
643 }
644 }
645 prev = current;
646 current = current->next;
647 }
648 }
649
650 /*
651 LOCKING: requires that the GC lock is held
652
653 Limitations: We scan all ephemerons on every collection since the current design doesn't allow for a simple nursery/mature split.
654 */
655 gboolean
656 sgen_client_mark_ephemerons (ScanCopyContext ctx)
657 {
658 CopyOrMarkObjectFunc copy_func = ctx.ops->copy_or_mark_object;
659 SgenGrayQueue *queue = ctx.queue;
660 gboolean nothing_marked = TRUE;
661 EphemeronLinkNode *current = ephemeron_list;
662 Ephemeron *cur, *array_end;
663 GCObject *tombstone;
664
665 for (current = ephemeron_list; current; current = current->next) {
666 MonoArray *array = current->array;
667 SGEN_LOG (5, "Ephemeron array at %p", array);
668
669 /*It has to be alive*/
670 if (!sgen_is_object_alive_for_current_gen ((GCObject*)array)) {
671 SGEN_LOG (5, "\tnot reachable");
672 continue;
673 }
674
675 copy_func ((GCObject**)&array, queue);
676
677 cur = mono_array_addr (array, Ephemeron, 0);
678 array_end = cur + mono_array_length_fast (array);
679 tombstone = SGEN_LOAD_VTABLE ((GCObject*)array)->domain->ephemeron_tombstone;
680
681 for (; cur < array_end; ++cur) {
682 GCObject *key = cur->key;
683
684 if (!key || key == tombstone)
685 continue;
686
687 SGEN_LOG (5, "[%zd] key %p (%s) value %p (%s)", cur - mono_array_addr (array, Ephemeron, 0),
688 key, sgen_is_object_alive_for_current_gen (key) ? "reachable" : "unreachable",
689 cur->value, cur->value && sgen_is_object_alive_for_current_gen (cur->value) ? "reachable" : "unreachable");
690
691 if (sgen_is_object_alive_for_current_gen (key)) {
692 GCObject *value = cur->value;
693
694 copy_func (&cur->key, queue);
695 if (value) {
696 if (!sgen_is_object_alive_for_current_gen (value))
697 nothing_marked = FALSE;
698 copy_func (&cur->value, queue);
699 }
700 }
701 }
702 }
703
704 SGEN_LOG (5, "Ephemeron run finished. Is it done %d", nothing_marked);
705 return nothing_marked;
706 }
707
708 gboolean
709 mono_gc_ephemeron_array_add (MonoObject *obj)
710 {
711 EphemeronLinkNode *node;
712
713 LOCK_GC;
714
715 node = (EphemeronLinkNode *)sgen_alloc_internal (INTERNAL_MEM_EPHEMERON_LINK);
716 if (!node) {
717 UNLOCK_GC;
718 return FALSE;
719 }
720 node->array = (MonoArray*)obj;
721 node->next = ephemeron_list;
722 ephemeron_list = node;
723
724 SGEN_LOG (5, "Registered ephemeron array %p", obj);
725
726 UNLOCK_GC;
727 return TRUE;
728 }
729
730 /*
731 * Appdomain handling
732 */
733
734 void
735 mono_gc_set_current_thread_appdomain (MonoDomain *domain)
736 {
737 SgenThreadInfo *info = mono_thread_info_current ();
738
739 /* Could be called from sgen_thread_unregister () with a NULL info */
740 if (domain) {
741 g_assert (info);
742 info->client_info.stopped_domain = domain;
743 }
744 }
745
746 static gboolean
747 need_remove_object_for_domain (GCObject *start, MonoDomain *domain)
748 {
749 if (mono_object_domain (start) == domain) {
750 SGEN_LOG (4, "Need to cleanup object %p", start);
751 binary_protocol_cleanup (start, (gpointer)SGEN_LOAD_VTABLE (start), sgen_safe_object_get_size ((GCObject*)start));
752 return TRUE;
753 }
754 return FALSE;
755 }
756
757 static void
758 process_object_for_domain_clearing (GCObject *start, MonoDomain *domain)
759 {
760 MonoVTable *vt = SGEN_LOAD_VTABLE (start);
761 if (vt->klass == mono_defaults.internal_thread_class)
762 g_assert (mono_object_domain (start) == mono_get_root_domain ());
763 /* The object could be a proxy for an object in the domain
764 we're deleting. */
765 #ifndef DISABLE_REMOTING
766 if (mono_defaults.real_proxy_class->supertypes && mono_class_has_parent_fast (vt->klass, mono_defaults.real_proxy_class)) {
767 MonoObject *server = ((MonoRealProxy*)start)->unwrapped_server;
768
769 /* The server could already have been zeroed out, so
770 we need to check for that, too. */
771 if (server && (!SGEN_LOAD_VTABLE (server) || mono_object_domain (server) == domain)) {
772 SGEN_LOG (4, "Cleaning up remote pointer in %p to object %p", start, server);
773 ((MonoRealProxy*)start)->unwrapped_server = NULL;
774 }
775 }
776 #endif
777 }
778
779 static gboolean
780 clear_domain_process_object (GCObject *obj, MonoDomain *domain)
781 {
782 gboolean remove;
783
784 process_object_for_domain_clearing (obj, domain);
785 remove = need_remove_object_for_domain (obj, domain);
786
787 if (remove && obj->synchronisation) {
788 guint32 dislink = mono_monitor_get_object_monitor_gchandle (obj);
789 if (dislink)
790 mono_gchandle_free (dislink);
791 }
792
793 return remove;
794 }
795
796 static void
797 clear_domain_process_minor_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
798 {
799 if (clear_domain_process_object (obj, domain)) {
800 CANARIFY_SIZE (size);
801 memset (obj, 0, size);
802 }
803 }
804
805 static void
806 clear_domain_process_major_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
807 {
808 clear_domain_process_object (obj, domain);
809 }
810
811 static void
812 clear_domain_free_major_non_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
813 {
814 if (need_remove_object_for_domain (obj, domain))
815 major_collector.free_non_pinned_object (obj, size);
816 }
817
818 static void
819 clear_domain_free_major_pinned_object_callback (GCObject *obj, size_t size, MonoDomain *domain)
820 {
821 if (need_remove_object_for_domain (obj, domain))
822 major_collector.free_pinned_object (obj, size);
823 }
824
825 /*
826 * When appdomains are unloaded we can easily remove objects that have finalizers,
827 * but all the others could still be present in random places on the heap.
828 * We need a sweep to get rid of them even though it's going to be costly
829 * with big heaps.
830 * The reason we need to remove them is because we access the vtable and class
831 * structures to know the object size and the reference bitmap: once the domain is
832 * unloaded the point to random memory.
833 */
834 void
835 mono_gc_clear_domain (MonoDomain * domain)
836 {
837 LOSObject *bigobj, *prev;
838 int i;
839
840 LOCK_GC;
841
842 binary_protocol_domain_unload_begin (domain);
843
844 sgen_stop_world (0);
845
846 if (sgen_concurrent_collection_in_progress ())
847 sgen_perform_collection (0, GENERATION_OLD, "clear domain", TRUE, FALSE);
848 SGEN_ASSERT (0, !sgen_concurrent_collection_in_progress (), "We just ordered a synchronous collection. Why are we collecting concurrently?");
849
850 major_collector.finish_sweeping ();
851
852 sgen_process_fin_stage_entries ();
853
854 sgen_clear_nursery_fragments ();
855
856 if (sgen_mono_xdomain_checks && domain != mono_get_root_domain ()) {
857 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_NORMAL);
858 sgen_scan_for_registered_roots_in_domain (domain, ROOT_TYPE_WBARRIER);
859 sgen_check_for_xdomain_refs ();
860 }
861
862 /*Ephemerons and dislinks must be processed before LOS since they might end up pointing
863 to memory returned to the OS.*/
864 null_ephemerons_for_domain (domain);
865 sgen_null_links_for_domain (domain);
866
867 for (i = GENERATION_NURSERY; i < GENERATION_MAX; ++i)
868 sgen_remove_finalizers_if (object_in_domain_predicate, domain, i);
869
870 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data,
871 (IterateObjectCallbackFunc)clear_domain_process_minor_object_callback, domain, FALSE, TRUE);
872
873 /* We need two passes over major and large objects because
874 freeing such objects might give their memory back to the OS
875 (in the case of large objects) or obliterate its vtable
876 (pinned objects with major-copying or pinned and non-pinned
877 objects with major-mark&sweep), but we might need to
878 dereference a pointer from an object to another object if
879 the first object is a proxy. */
880 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, (IterateObjectCallbackFunc)clear_domain_process_major_object_callback, domain);
881 for (bigobj = los_object_list; bigobj; bigobj = bigobj->next)
882 clear_domain_process_object ((GCObject*)bigobj->data, domain);
883
884 prev = NULL;
885 for (bigobj = los_object_list; bigobj;) {
886 if (need_remove_object_for_domain ((GCObject*)bigobj->data, domain)) {
887 LOSObject *to_free = bigobj;
888 if (prev)
889 prev->next = bigobj->next;
890 else
891 los_object_list = bigobj->next;
892 bigobj = bigobj->next;
893 SGEN_LOG (4, "Freeing large object %p", bigobj->data);
894 sgen_los_free_object (to_free);
895 continue;
896 }
897 prev = bigobj;
898 bigobj = bigobj->next;
899 }
900 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_NON_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_non_pinned_object_callback, domain);
901 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_PINNED, (IterateObjectCallbackFunc)clear_domain_free_major_pinned_object_callback, domain);
902
903 if (domain == mono_get_root_domain ()) {
904 sgen_pin_stats_report ();
905 sgen_object_layout_dump (stdout);
906 }
907
908 sgen_restart_world (0);
909
910 binary_protocol_domain_unload_end (domain);
911 binary_protocol_flush_buffers (FALSE);
912
913 UNLOCK_GC;
914 }
915
916 /*
917 * Allocation
918 */
919
920 static gboolean alloc_events = FALSE;
921
922 void
923 mono_gc_enable_alloc_events (void)
924 {
925 alloc_events = TRUE;
926 }
927
928 void*
929 mono_gc_alloc_obj (MonoVTable *vtable, size_t size)
930 {
931 MonoObject *obj = sgen_alloc_obj (vtable, size);
932
933 if (G_UNLIKELY (alloc_events)) {
934 if (obj)
935 mono_profiler_allocation (obj);
936 }
937
938 return obj;
939 }
940
941 void*
942 mono_gc_alloc_pinned_obj (MonoVTable *vtable, size_t size)
943 {
944 MonoObject *obj = sgen_alloc_obj_pinned (vtable, size);
945
946 if (G_UNLIKELY (alloc_events)) {
947 if (obj)
948 mono_profiler_allocation (obj);
949 }
950
951 return obj;
952 }
953
954 void*
955 mono_gc_alloc_mature (MonoVTable *vtable, size_t size)
956 {
957 MonoObject *obj = sgen_alloc_obj_mature (vtable, size);
958
959 if (G_UNLIKELY (alloc_events)) {
960 if (obj)
961 mono_profiler_allocation (obj);
962 }
963
964 return obj;
965 }
966
967 void*
968 mono_gc_alloc_fixed (size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
969 {
970 /* FIXME: do a single allocation */
971 void *res = calloc (1, size);
972 if (!res)
973 return NULL;
974 if (!mono_gc_register_root ((char *)res, size, descr, source, msg)) {
975 free (res);
976 res = NULL;
977 }
978 return res;
979 }
980
981 void
982 mono_gc_free_fixed (void* addr)
983 {
984 mono_gc_deregister_root ((char *)addr);
985 free (addr);
986 }
987
988 /*
989 * Managed allocator
990 */
991
992 static MonoMethod* alloc_method_cache [ATYPE_NUM];
993 static MonoMethod* slowpath_alloc_method_cache [ATYPE_NUM];
994 static gboolean use_managed_allocator = TRUE;
995
996 #ifdef MANAGED_ALLOCATION
997
998 #if defined(HAVE_KW_THREAD) || defined(TARGET_OSX) || defined(TARGET_WIN32) || defined(TARGET_ANDROID) || defined(TARGET_IOS)
999
1000 // Cache the SgenThreadInfo pointer in a local 'var'.
1001 #define EMIT_TLS_ACCESS_VAR(mb, var) \
1002 do { \
1003 var = mono_mb_add_local ((mb), &mono_defaults.int_class->byval_arg); \
1004 mono_mb_emit_byte ((mb), MONO_CUSTOM_PREFIX); \
1005 mono_mb_emit_byte ((mb), CEE_MONO_TLS); \
1006 mono_mb_emit_i4 ((mb), TLS_KEY_SGEN_THREAD_INFO); \
1007 mono_mb_emit_stloc ((mb), (var)); \
1008 } while (0)
1009
1010 #define EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR(mb, var) \
1011 do { \
1012 mono_mb_emit_ldloc ((mb), (var)); \
1013 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenClientThreadInfo, in_critical_region)); \
1014 mono_mb_emit_byte ((mb), CEE_ADD); \
1015 } while (0)
1016
1017 #define EMIT_TLS_ACCESS_NEXT_ADDR(mb, var) do { \
1018 mono_mb_emit_ldloc ((mb), (var)); \
1019 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenThreadInfo, tlab_next)); \
1020 mono_mb_emit_byte ((mb), CEE_ADD); \
1021 } while (0)
1022
1023 #define EMIT_TLS_ACCESS_TEMP_END(mb, var) do { \
1024 mono_mb_emit_ldloc ((mb), (var)); \
1025 mono_mb_emit_icon ((mb), MONO_STRUCT_OFFSET (SgenThreadInfo, tlab_temp_end)); \
1026 mono_mb_emit_byte ((mb), CEE_ADD); \
1027 mono_mb_emit_byte ((mb), CEE_LDIND_I); \
1028 } while (0)
1029
1030 #else
1031 #define EMIT_TLS_ACCESS_VAR(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1032 #define EMIT_TLS_ACCESS_NEXT_ADDR(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1033 #define EMIT_TLS_ACCESS_TEMP_END(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1034 #define EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR(mb, _var) do { g_error ("sgen is not supported when using --with-tls=pthread.\n"); } while (0)
1035
1036 #endif
1037
1038 /* FIXME: Do this in the JIT, where specialized allocation sequences can be created
1039 * for each class. This is currently not easy to do, as it is hard to generate basic
1040 * blocks + branches, but it is easy with the linear IL codebase.
1041 *
1042 * For this to work we'd need to solve the TLAB race, first. Now we
1043 * require the allocator to be in a few known methods to make sure
1044 * that they are executed atomically via the restart mechanism.
1045 */
1046 static MonoMethod*
1047 create_allocator (int atype, ManagedAllocatorVariant variant)
1048 {
1049 int p_var, size_var, thread_var G_GNUC_UNUSED;
1050 gboolean slowpath = variant == MANAGED_ALLOCATOR_SLOW_PATH;
1051 guint32 slowpath_branch, max_size_branch;
1052 MonoMethodBuilder *mb;
1053 MonoMethod *res;
1054 MonoMethodSignature *csig;
1055 static gboolean registered = FALSE;
1056 int tlab_next_addr_var, new_next_var;
1057 const char *name = NULL;
1058 WrapperInfo *info;
1059 int num_params, i;
1060
1061 if (!registered) {
1062 mono_register_jit_icall (mono_gc_alloc_obj, "mono_gc_alloc_obj", mono_create_icall_signature ("object ptr int"), FALSE);
1063 mono_register_jit_icall (mono_gc_alloc_vector, "mono_gc_alloc_vector", mono_create_icall_signature ("object ptr int int"), FALSE);
1064 mono_register_jit_icall (mono_gc_alloc_string, "mono_gc_alloc_string", mono_create_icall_signature ("object ptr int int32"), FALSE);
1065 registered = TRUE;
1066 }
1067
1068 if (atype == ATYPE_SMALL) {
1069 name = slowpath ? "SlowAllocSmall" : "AllocSmall";
1070 } else if (atype == ATYPE_NORMAL) {
1071 name = slowpath ? "SlowAlloc" : "Alloc";
1072 } else if (atype == ATYPE_VECTOR) {
1073 name = slowpath ? "SlowAllocVector" : "AllocVector";
1074 } else if (atype == ATYPE_STRING) {
1075 name = slowpath ? "SlowAllocString" : "AllocString";
1076 } else {
1077 g_assert_not_reached ();
1078 }
1079
1080 if (atype == ATYPE_NORMAL)
1081 num_params = 1;
1082 else
1083 num_params = 2;
1084
1085 csig = mono_metadata_signature_alloc (mono_defaults.corlib, num_params);
1086 if (atype == ATYPE_STRING) {
1087 csig->ret = &mono_defaults.string_class->byval_arg;
1088 csig->params [0] = &mono_defaults.int_class->byval_arg;
1089 csig->params [1] = &mono_defaults.int32_class->byval_arg;
1090 } else {
1091 csig->ret = &mono_defaults.object_class->byval_arg;
1092 for (i = 0; i < num_params; i++)
1093 csig->params [i] = &mono_defaults.int_class->byval_arg;
1094 }
1095
1096 mb = mono_mb_new (mono_defaults.object_class, name, MONO_WRAPPER_ALLOC);
1097
1098 #ifndef DISABLE_JIT
1099 if (slowpath) {
1100 switch (atype) {
1101 case ATYPE_NORMAL:
1102 case ATYPE_SMALL:
1103 mono_mb_emit_ldarg (mb, 0);
1104 mono_mb_emit_icall (mb, ves_icall_object_new_specific);
1105 break;
1106 case ATYPE_VECTOR:
1107 mono_mb_emit_ldarg (mb, 0);
1108 mono_mb_emit_ldarg (mb, 1);
1109 mono_mb_emit_icall (mb, ves_icall_array_new_specific);
1110 break;
1111 case ATYPE_STRING:
1112 mono_mb_emit_ldarg (mb, 1);
1113 mono_mb_emit_icall (mb, ves_icall_string_alloc);
1114 break;
1115 default:
1116 g_assert_not_reached ();
1117 }
1118
1119 goto done;
1120 }
1121
1122 /*
1123 * Tls access might call foreign code or code without jinfo. This can
1124 * only happen if we are outside of the critical region.
1125 */
1126 EMIT_TLS_ACCESS_VAR (mb, thread_var);
1127
1128 size_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1129 if (atype == ATYPE_SMALL) {
1130 /* size_var = size_arg */
1131 mono_mb_emit_ldarg (mb, 1);
1132 mono_mb_emit_stloc (mb, size_var);
1133 } else if (atype == ATYPE_NORMAL) {
1134 /* size = vtable->klass->instance_size; */
1135 mono_mb_emit_ldarg (mb, 0);
1136 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1137 mono_mb_emit_byte (mb, CEE_ADD);
1138 mono_mb_emit_byte (mb, CEE_LDIND_I);
1139 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, instance_size));
1140 mono_mb_emit_byte (mb, CEE_ADD);
1141 /* FIXME: assert instance_size stays a 4 byte integer */
1142 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1143 mono_mb_emit_byte (mb, CEE_CONV_I);
1144 mono_mb_emit_stloc (mb, size_var);
1145 } else if (atype == ATYPE_VECTOR) {
1146 MonoExceptionClause *clause;
1147 int pos, pos_leave, pos_error;
1148 MonoClass *oom_exc_class;
1149 MonoMethod *ctor;
1150
1151 /*
1152 * n > MONO_ARRAY_MAX_INDEX => OutOfMemoryException
1153 * n < 0 => OverflowException
1154 *
1155 * We can do an unsigned comparison to catch both cases, then in the error
1156 * case compare signed to distinguish between them.
1157 */
1158 mono_mb_emit_ldarg (mb, 1);
1159 mono_mb_emit_icon (mb, MONO_ARRAY_MAX_INDEX);
1160 mono_mb_emit_byte (mb, CEE_CONV_U);
1161 pos = mono_mb_emit_short_branch (mb, CEE_BLE_UN_S);
1162
1163 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1164 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1165 mono_mb_emit_ldarg (mb, 1);
1166 mono_mb_emit_icon (mb, 0);
1167 pos_error = mono_mb_emit_short_branch (mb, CEE_BLT_S);
1168 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1169 mono_mb_patch_short_branch (mb, pos_error);
1170 mono_mb_emit_exception (mb, "OverflowException", NULL);
1171
1172 mono_mb_patch_short_branch (mb, pos);
1173
1174 clause = (MonoExceptionClause *)mono_image_alloc0 (mono_defaults.corlib, sizeof (MonoExceptionClause));
1175 clause->try_offset = mono_mb_get_label (mb);
1176
1177 /* vtable->klass->sizes.element_size */
1178 mono_mb_emit_ldarg (mb, 0);
1179 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoVTable, klass));
1180 mono_mb_emit_byte (mb, CEE_ADD);
1181 mono_mb_emit_byte (mb, CEE_LDIND_I);
1182 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoClass, sizes));
1183 mono_mb_emit_byte (mb, CEE_ADD);
1184 mono_mb_emit_byte (mb, CEE_LDIND_U4);
1185 mono_mb_emit_byte (mb, CEE_CONV_I);
1186
1187 /* * n */
1188 mono_mb_emit_ldarg (mb, 1);
1189 mono_mb_emit_byte (mb, CEE_MUL_OVF_UN);
1190 /* + sizeof (MonoArray) */
1191 mono_mb_emit_icon (mb, MONO_SIZEOF_MONO_ARRAY);
1192 mono_mb_emit_byte (mb, CEE_ADD_OVF_UN);
1193 mono_mb_emit_stloc (mb, size_var);
1194
1195 pos_leave = mono_mb_emit_branch (mb, CEE_LEAVE);
1196
1197 /* catch */
1198 clause->flags = MONO_EXCEPTION_CLAUSE_NONE;
1199 clause->try_len = mono_mb_get_pos (mb) - clause->try_offset;
1200 clause->data.catch_class = mono_class_load_from_name (mono_defaults.corlib,
1201 "System", "OverflowException");
1202 clause->handler_offset = mono_mb_get_label (mb);
1203
1204 oom_exc_class = mono_class_load_from_name (mono_defaults.corlib,
1205 "System", "OutOfMemoryException");
1206 ctor = mono_class_get_method_from_name (oom_exc_class, ".ctor", 0);
1207 g_assert (ctor);
1208
1209 mono_mb_emit_byte (mb, CEE_POP);
1210 mono_mb_emit_op (mb, CEE_NEWOBJ, ctor);
1211 mono_mb_emit_byte (mb, CEE_THROW);
1212
1213 clause->handler_len = mono_mb_get_pos (mb) - clause->handler_offset;
1214 mono_mb_set_clauses (mb, 1, clause);
1215 mono_mb_patch_branch (mb, pos_leave);
1216 /* end catch */
1217 } else if (atype == ATYPE_STRING) {
1218 int pos;
1219
1220 /*
1221 * a string allocator method takes the args: (vtable, len)
1222 *
1223 * bytes = offsetof (MonoString, chars) + ((len + 1) * 2)
1224 *
1225 * condition:
1226 *
1227 * bytes <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1228 *
1229 * therefore:
1230 *
1231 * offsetof (MonoString, chars) + ((len + 1) * 2) <= INT32_MAX - (SGEN_ALLOC_ALIGN - 1)
1232 * len <= (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - offsetof (MonoString, chars)) / 2 - 1
1233 */
1234 mono_mb_emit_ldarg (mb, 1);
1235 mono_mb_emit_icon (mb, (INT32_MAX - (SGEN_ALLOC_ALIGN - 1) - MONO_STRUCT_OFFSET (MonoString, chars)) / 2 - 1);
1236 pos = mono_mb_emit_short_branch (mb, MONO_CEE_BLE_UN_S);
1237
1238 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1239 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1240 mono_mb_emit_exception (mb, "OutOfMemoryException", NULL);
1241 mono_mb_patch_short_branch (mb, pos);
1242
1243 mono_mb_emit_ldarg (mb, 1);
1244 mono_mb_emit_icon (mb, 1);
1245 mono_mb_emit_byte (mb, MONO_CEE_SHL);
1246 //WE manually fold the above + 2 here
1247 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, chars) + 2);
1248 mono_mb_emit_byte (mb, CEE_ADD);
1249 mono_mb_emit_stloc (mb, size_var);
1250 } else {
1251 g_assert_not_reached ();
1252 }
1253
1254 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1255 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1256 mono_mb_emit_byte (mb, CEE_LDC_I4_1);
1257 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1258 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1259 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1260 #endif
1261
1262 /* size += ALLOC_ALIGN - 1; */
1263 mono_mb_emit_ldloc (mb, size_var);
1264 mono_mb_emit_icon (mb, SGEN_ALLOC_ALIGN - 1);
1265 mono_mb_emit_byte (mb, CEE_ADD);
1266 /* size &= ~(ALLOC_ALIGN - 1); */
1267 mono_mb_emit_icon (mb, ~(SGEN_ALLOC_ALIGN - 1));
1268 mono_mb_emit_byte (mb, CEE_AND);
1269 mono_mb_emit_stloc (mb, size_var);
1270
1271 /* if (size > MAX_SMALL_OBJ_SIZE) goto slowpath */
1272 if (atype != ATYPE_SMALL) {
1273 mono_mb_emit_ldloc (mb, size_var);
1274 mono_mb_emit_icon (mb, SGEN_MAX_SMALL_OBJ_SIZE);
1275 max_size_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BGT_UN_S);
1276 }
1277
1278 /*
1279 * We need to modify tlab_next, but the JIT only supports reading, so we read
1280 * another tls var holding its address instead.
1281 */
1282
1283 /* tlab_next_addr (local) = tlab_next_addr (TLS var) */
1284 tlab_next_addr_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1285 EMIT_TLS_ACCESS_NEXT_ADDR (mb, thread_var);
1286 mono_mb_emit_stloc (mb, tlab_next_addr_var);
1287
1288 /* p = (void**)tlab_next; */
1289 p_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1290 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1291 mono_mb_emit_byte (mb, CEE_LDIND_I);
1292 mono_mb_emit_stloc (mb, p_var);
1293
1294 /* new_next = (char*)p + size; */
1295 new_next_var = mono_mb_add_local (mb, &mono_defaults.int_class->byval_arg);
1296 mono_mb_emit_ldloc (mb, p_var);
1297 mono_mb_emit_ldloc (mb, size_var);
1298 mono_mb_emit_byte (mb, CEE_CONV_I);
1299 mono_mb_emit_byte (mb, CEE_ADD);
1300 mono_mb_emit_stloc (mb, new_next_var);
1301
1302 /* if (G_LIKELY (new_next < tlab_temp_end)) */
1303 mono_mb_emit_ldloc (mb, new_next_var);
1304 EMIT_TLS_ACCESS_TEMP_END (mb, thread_var);
1305 slowpath_branch = mono_mb_emit_short_branch (mb, MONO_CEE_BLT_UN_S);
1306
1307 /* Slowpath */
1308 if (atype != ATYPE_SMALL)
1309 mono_mb_patch_short_branch (mb, max_size_branch);
1310
1311 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1312 mono_mb_emit_byte (mb, CEE_MONO_NOT_TAKEN);
1313 /*
1314 * We are no longer in a critical section. We need to do this before calling
1315 * to unmanaged land in order to avoid stw deadlocks since unmanaged code
1316 * might take locks.
1317 */
1318 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1319 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1320 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1321 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1322 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1323 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_NONE);
1324 #endif
1325
1326 /* FIXME: mono_gc_alloc_obj takes a 'size_t' as an argument, not an int32 */
1327 mono_mb_emit_ldarg (mb, 0);
1328 mono_mb_emit_ldloc (mb, size_var);
1329 if (atype == ATYPE_NORMAL || atype == ATYPE_SMALL) {
1330 mono_mb_emit_icall (mb, mono_gc_alloc_obj);
1331 } else if (atype == ATYPE_VECTOR) {
1332 mono_mb_emit_ldarg (mb, 1);
1333 mono_mb_emit_icall (mb, mono_gc_alloc_vector);
1334 } else if (atype == ATYPE_STRING) {
1335 mono_mb_emit_ldarg (mb, 1);
1336 mono_mb_emit_icall (mb, mono_gc_alloc_string);
1337 } else {
1338 g_assert_not_reached ();
1339 }
1340 mono_mb_emit_byte (mb, CEE_RET);
1341
1342 /* Fastpath */
1343 mono_mb_patch_short_branch (mb, slowpath_branch);
1344
1345 /* FIXME: Memory barrier */
1346
1347 /* tlab_next = new_next */
1348 mono_mb_emit_ldloc (mb, tlab_next_addr_var);
1349 mono_mb_emit_ldloc (mb, new_next_var);
1350 mono_mb_emit_byte (mb, CEE_STIND_I);
1351
1352 /* *p = vtable; */
1353 mono_mb_emit_ldloc (mb, p_var);
1354 mono_mb_emit_ldarg (mb, 0);
1355 mono_mb_emit_byte (mb, CEE_STIND_I);
1356
1357 if (atype == ATYPE_VECTOR) {
1358 /* arr->max_length = max_length; */
1359 mono_mb_emit_ldloc (mb, p_var);
1360 mono_mb_emit_ldflda (mb, MONO_STRUCT_OFFSET (MonoArray, max_length));
1361 mono_mb_emit_ldarg (mb, 1);
1362 #ifdef MONO_BIG_ARRAYS
1363 mono_mb_emit_byte (mb, CEE_STIND_I);
1364 #else
1365 mono_mb_emit_byte (mb, CEE_STIND_I4);
1366 #endif
1367 } else if (atype == ATYPE_STRING) {
1368 /* need to set length and clear the last char */
1369 /* s->length = len; */
1370 mono_mb_emit_ldloc (mb, p_var);
1371 mono_mb_emit_icon (mb, MONO_STRUCT_OFFSET (MonoString, length));
1372 mono_mb_emit_byte (mb, MONO_CEE_ADD);
1373 mono_mb_emit_ldarg (mb, 1);
1374 mono_mb_emit_byte (mb, MONO_CEE_STIND_I4);
1375 }
1376
1377 #ifdef MANAGED_ALLOCATOR_CAN_USE_CRITICAL_REGION
1378 EMIT_TLS_ACCESS_IN_CRITICAL_REGION_ADDR (mb, thread_var);
1379 mono_mb_emit_byte (mb, CEE_LDC_I4_0);
1380 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1381 mono_mb_emit_byte (mb, CEE_MONO_ATOMIC_STORE_I4);
1382 #else
1383 mono_mb_emit_byte (mb, MONO_CUSTOM_PREFIX);
1384 mono_mb_emit_byte (mb, CEE_MONO_MEMORY_BARRIER);
1385 #endif
1386 /*
1387 We must make sure both vtable and max_length are globaly visible before returning to managed land.
1388 */
1389 mono_mb_emit_i4 (mb, MONO_MEMORY_BARRIER_REL);
1390
1391 /* return p */
1392 mono_mb_emit_ldloc (mb, p_var);
1393
1394 done:
1395 mono_mb_emit_byte (mb, CEE_RET);
1396 #endif
1397
1398 info = mono_wrapper_info_create (mb, WRAPPER_SUBTYPE_NONE);
1399 info->d.alloc.gc_name = "sgen";
1400 info->d.alloc.alloc_type = atype;
1401
1402 #ifndef DISABLE_JIT
1403 mb->init_locals = FALSE;
1404 #endif
1405
1406 res = mono_mb_create (mb, csig, 8, info);
1407 mono_mb_free (mb);
1408
1409
1410 return res;
1411 }
1412 #endif
1413
1414 int
1415 mono_gc_get_aligned_size_for_allocator (int size)
1416 {
1417 return SGEN_ALIGN_UP (size);
1418 }
1419
1420 /*
1421 * Generate an allocator method implementing the fast path of mono_gc_alloc_obj ().
1422 * The signature of the called method is:
1423 * object allocate (MonoVTable *vtable)
1424 */
1425 MonoMethod*
1426 mono_gc_get_managed_allocator (MonoClass *klass, gboolean for_box, gboolean known_instance_size)
1427 {
1428 #ifdef MANAGED_ALLOCATION
1429 if (collect_before_allocs)
1430 return NULL;
1431 if (!mono_runtime_has_tls_get ())
1432 return NULL;
1433 if (klass->instance_size > tlab_size)
1434 return NULL;
1435 if (known_instance_size && ALIGN_TO (klass->instance_size, SGEN_ALLOC_ALIGN) >= SGEN_MAX_SMALL_OBJ_SIZE)
1436 return NULL;
1437 if (mono_class_has_finalizer (klass) || mono_class_is_marshalbyref (klass))
1438 return NULL;
1439 if (klass->rank)
1440 return NULL;
1441 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1442 return NULL;
1443 if (klass->byval_arg.type == MONO_TYPE_STRING)
1444 return mono_gc_get_managed_allocator_by_type (ATYPE_STRING, MANAGED_ALLOCATOR_REGULAR);
1445 /* Generic classes have dynamic field and can go above MAX_SMALL_OBJ_SIZE. */
1446 if (known_instance_size)
1447 return mono_gc_get_managed_allocator_by_type (ATYPE_SMALL, MANAGED_ALLOCATOR_REGULAR);
1448 else
1449 return mono_gc_get_managed_allocator_by_type (ATYPE_NORMAL, MANAGED_ALLOCATOR_REGULAR);
1450 #else
1451 return NULL;
1452 #endif
1453 }
1454
1455 MonoMethod*
1456 mono_gc_get_managed_array_allocator (MonoClass *klass)
1457 {
1458 #ifdef MANAGED_ALLOCATION
1459 if (klass->rank != 1)
1460 return NULL;
1461 if (!mono_runtime_has_tls_get ())
1462 return NULL;
1463 if (mono_profiler_get_events () & MONO_PROFILE_ALLOCATIONS)
1464 return NULL;
1465 if (has_per_allocation_action)
1466 return NULL;
1467 g_assert (!mono_class_has_finalizer (klass) && !mono_class_is_marshalbyref (klass));
1468
1469 return mono_gc_get_managed_allocator_by_type (ATYPE_VECTOR, MANAGED_ALLOCATOR_REGULAR);
1470 #else
1471 return NULL;
1472 #endif
1473 }
1474
1475 void
1476 sgen_set_use_managed_allocator (gboolean flag)
1477 {
1478 use_managed_allocator = flag;
1479 }
1480
1481 MonoMethod*
1482 mono_gc_get_managed_allocator_by_type (int atype, ManagedAllocatorVariant variant)
1483 {
1484 #ifdef MANAGED_ALLOCATION
1485 MonoMethod *res;
1486 MonoMethod **cache;
1487
1488 if (variant == MANAGED_ALLOCATOR_REGULAR && !use_managed_allocator)
1489 return NULL;
1490
1491 if (variant == MANAGED_ALLOCATOR_REGULAR && !mono_runtime_has_tls_get ())
1492 return NULL;
1493
1494 switch (variant) {
1495 case MANAGED_ALLOCATOR_REGULAR: cache = alloc_method_cache; break;
1496 case MANAGED_ALLOCATOR_SLOW_PATH: cache = slowpath_alloc_method_cache; break;
1497 default: g_assert_not_reached (); break;
1498 }
1499
1500 res = cache [atype];
1501 if (res)
1502 return res;
1503
1504 res = create_allocator (atype, variant);
1505 LOCK_GC;
1506 if (cache [atype]) {
1507 mono_free_method (res);
1508 res = cache [atype];
1509 } else {
1510 mono_memory_barrier ();
1511 cache [atype] = res;
1512 }
1513 UNLOCK_GC;
1514
1515 return res;
1516 #else
1517 return NULL;
1518 #endif
1519 }
1520
1521 guint32
1522 mono_gc_get_managed_allocator_types (void)
1523 {
1524 return ATYPE_NUM;
1525 }
1526
1527 gboolean
1528 sgen_is_managed_allocator (MonoMethod *method)
1529 {
1530 int i;
1531
1532 for (i = 0; i < ATYPE_NUM; ++i)
1533 if (method == alloc_method_cache [i] || method == slowpath_alloc_method_cache [i])
1534 return TRUE;
1535 return FALSE;
1536 }
1537
1538 gboolean
1539 sgen_has_managed_allocator (void)
1540 {
1541 int i;
1542
1543 for (i = 0; i < ATYPE_NUM; ++i)
1544 if (alloc_method_cache [i] || slowpath_alloc_method_cache [i])
1545 return TRUE;
1546 return FALSE;
1547 }
1548
1549 /*
1550 * Cardtable scanning
1551 */
1552
1553 #define MWORD_MASK (sizeof (mword) - 1)
1554
1555 static inline int
1556 find_card_offset (mword card)
1557 {
1558 /*XXX Use assembly as this generates some pretty bad code */
1559 #if defined(__i386__) && defined(__GNUC__)
1560 return (__builtin_ffs (card) - 1) / 8;
1561 #elif defined(__x86_64__) && defined(__GNUC__)
1562 return (__builtin_ffsll (card) - 1) / 8;
1563 #elif defined(__s390x__)
1564 return (__builtin_ffsll (GUINT64_TO_LE(card)) - 1) / 8;
1565 #else
1566 int i;
1567 guint8 *ptr = (guint8 *) &card;
1568 for (i = 0; i < sizeof (mword); ++i) {
1569 if (ptr[i])
1570 return i;
1571 }
1572 return 0;
1573 #endif
1574 }
1575
1576 static guint8*
1577 find_next_card (guint8 *card_data, guint8 *end)
1578 {
1579 mword *cards, *cards_end;
1580 mword card;
1581
1582 while ((((mword)card_data) & MWORD_MASK) && card_data < end) {
1583 if (*card_data)
1584 return card_data;
1585 ++card_data;
1586 }
1587
1588 if (card_data == end)
1589 return end;
1590
1591 cards = (mword*)card_data;
1592 cards_end = (mword*)((mword)end & ~MWORD_MASK);
1593 while (cards < cards_end) {
1594 card = *cards;
1595 if (card)
1596 return (guint8*)cards + find_card_offset (card);
1597 ++cards;
1598 }
1599
1600 card_data = (guint8*)cards_end;
1601 while (card_data < end) {
1602 if (*card_data)
1603 return card_data;
1604 ++card_data;
1605 }
1606
1607 return end;
1608 }
1609
1610 #define ARRAY_OBJ_INDEX(ptr,array,elem_size) (((char*)(ptr) - ((char*)(array) + G_STRUCT_OFFSET (MonoArray, vector))) / (elem_size))
1611
1612 gboolean
1613 sgen_client_cardtable_scan_object (GCObject *obj, mword block_obj_size, guint8 *cards, ScanCopyContext ctx)
1614 {
1615 MonoVTable *vt = SGEN_LOAD_VTABLE (obj);
1616 MonoClass *klass = vt->klass;
1617
1618 SGEN_ASSERT (0, SGEN_VTABLE_HAS_REFERENCES (vt), "Why would we ever call this on reference-free objects?");
1619
1620 if (vt->rank) {
1621 MonoArray *arr = (MonoArray*)obj;
1622 guint8 *card_data, *card_base;
1623 guint8 *card_data_end;
1624 char *obj_start = (char *)sgen_card_table_align_pointer (obj);
1625 mword bounds_size;
1626 mword obj_size = sgen_mono_array_size (vt, arr, &bounds_size, sgen_vtable_get_descriptor (vt));
1627 /* We don't want to scan the bounds entries at the end of multidimensional arrays */
1628 char *obj_end = (char*)obj + obj_size - bounds_size;
1629 size_t card_count;
1630 size_t extra_idx = 0;
1631
1632 mword desc = (mword)klass->element_class->gc_descr;
1633 int elem_size = mono_array_element_size (klass);
1634
1635 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1636 guint8 *overflow_scan_end = NULL;
1637 #endif
1638
1639 #ifdef SGEN_OBJECT_LAYOUT_STATISTICS
1640 if (klass->element_class->valuetype)
1641 sgen_object_layout_scanned_vtype_array ();
1642 else
1643 sgen_object_layout_scanned_ref_array ();
1644 #endif
1645
1646 if (cards)
1647 card_data = cards;
1648 else
1649 card_data = sgen_card_table_get_card_scan_address ((mword)obj);
1650
1651 card_base = card_data;
1652 card_count = sgen_card_table_number_of_cards_in_range ((mword)obj, obj_size);
1653 card_data_end = card_data + card_count;
1654
1655
1656 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1657 /*Check for overflow and if so, setup to scan in two steps*/
1658 if (!cards && card_data_end >= SGEN_SHADOW_CARDTABLE_END) {
1659 overflow_scan_end = sgen_shadow_cardtable + (card_data_end - SGEN_SHADOW_CARDTABLE_END);
1660 card_data_end = SGEN_SHADOW_CARDTABLE_END;
1661 }
1662
1663 LOOP_HEAD:
1664 #endif
1665
1666 card_data = find_next_card (card_data, card_data_end);
1667 for (; card_data < card_data_end; card_data = find_next_card (card_data + 1, card_data_end)) {
1668 size_t index;
1669 size_t idx = (card_data - card_base) + extra_idx;
1670 char *start = (char*)(obj_start + idx * CARD_SIZE_IN_BYTES);
1671 char *card_end = start + CARD_SIZE_IN_BYTES;
1672 char *first_elem, *elem;
1673
1674 HEAVY_STAT (++los_marked_cards);
1675
1676 if (!cards)
1677 sgen_card_table_prepare_card_for_scanning (card_data);
1678
1679 card_end = MIN (card_end, obj_end);
1680
1681 if (start <= (char*)arr->vector)
1682 index = 0;
1683 else
1684 index = ARRAY_OBJ_INDEX (start, obj, elem_size);
1685
1686 elem = first_elem = (char*)mono_array_addr_with_size_fast ((MonoArray*)obj, elem_size, index);
1687 if (klass->element_class->valuetype) {
1688 ScanVTypeFunc scan_vtype_func = ctx.ops->scan_vtype;
1689
1690 for (; elem < card_end; elem += elem_size)
1691 scan_vtype_func (obj, elem, desc, ctx.queue BINARY_PROTOCOL_ARG (elem_size));
1692 } else {
1693 ScanPtrFieldFunc scan_ptr_field_func = ctx.ops->scan_ptr_field;
1694
1695 HEAVY_STAT (++los_array_cards);
1696 for (; elem < card_end; elem += SIZEOF_VOID_P)
1697 scan_ptr_field_func (obj, (GCObject**)elem, ctx.queue);
1698 }
1699
1700 binary_protocol_card_scan (first_elem, elem - first_elem);
1701 }
1702
1703 #ifdef SGEN_HAVE_OVERLAPPING_CARDS
1704 if (overflow_scan_end) {
1705 extra_idx = card_data - card_base;
1706 card_base = card_data = sgen_shadow_cardtable;
1707 card_data_end = overflow_scan_end;
1708 overflow_scan_end = NULL;
1709 goto LOOP_HEAD;
1710 }
1711 #endif
1712 return TRUE;
1713 }
1714
1715 return FALSE;
1716 }
1717
1718 /*
1719 * Array and string allocation
1720 */
1721
1722 void*
1723 mono_gc_alloc_vector (MonoVTable *vtable, size_t size, uintptr_t max_length)
1724 {
1725 MonoArray *arr;
1726 TLAB_ACCESS_INIT;
1727
1728 if (!SGEN_CAN_ALIGN_UP (size))
1729 return NULL;
1730
1731 #ifndef DISABLE_CRITICAL_REGION
1732 ENTER_CRITICAL_REGION;
1733 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1734 if (arr) {
1735 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1736 arr->max_length = (mono_array_size_t)max_length;
1737 EXIT_CRITICAL_REGION;
1738 goto done;
1739 }
1740 EXIT_CRITICAL_REGION;
1741 #endif
1742
1743 LOCK_GC;
1744
1745 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1746 if (G_UNLIKELY (!arr)) {
1747 UNLOCK_GC;
1748 return NULL;
1749 }
1750
1751 arr->max_length = (mono_array_size_t)max_length;
1752
1753 UNLOCK_GC;
1754
1755 done:
1756 if (G_UNLIKELY (alloc_events))
1757 mono_profiler_allocation (&arr->obj);
1758
1759 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Vector has incorrect size.");
1760 return arr;
1761 }
1762
1763 void*
1764 mono_gc_alloc_array (MonoVTable *vtable, size_t size, uintptr_t max_length, uintptr_t bounds_size)
1765 {
1766 MonoArray *arr;
1767 MonoArrayBounds *bounds;
1768 TLAB_ACCESS_INIT;
1769
1770 if (!SGEN_CAN_ALIGN_UP (size))
1771 return NULL;
1772
1773 #ifndef DISABLE_CRITICAL_REGION
1774 ENTER_CRITICAL_REGION;
1775 arr = (MonoArray*)sgen_try_alloc_obj_nolock (vtable, size);
1776 if (arr) {
1777 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1778 arr->max_length = (mono_array_size_t)max_length;
1779
1780 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1781 arr->bounds = bounds;
1782 EXIT_CRITICAL_REGION;
1783 goto done;
1784 }
1785 EXIT_CRITICAL_REGION;
1786 #endif
1787
1788 LOCK_GC;
1789
1790 arr = (MonoArray*)sgen_alloc_obj_nolock (vtable, size);
1791 if (G_UNLIKELY (!arr)) {
1792 UNLOCK_GC;
1793 return NULL;
1794 }
1795
1796 arr->max_length = (mono_array_size_t)max_length;
1797
1798 bounds = (MonoArrayBounds*)((char*)arr + size - bounds_size);
1799 arr->bounds = bounds;
1800
1801 UNLOCK_GC;
1802
1803 done:
1804 if (G_UNLIKELY (alloc_events))
1805 mono_profiler_allocation (&arr->obj);
1806
1807 SGEN_ASSERT (6, SGEN_ALIGN_UP (size) == SGEN_ALIGN_UP (sgen_client_par_object_get_size (vtable, (GCObject*)arr)), "Array has incorrect size.");
1808 return arr;
1809 }
1810
1811 void*
1812 mono_gc_alloc_string (MonoVTable *vtable, size_t size, gint32 len)
1813 {
1814 MonoString *str;
1815 TLAB_ACCESS_INIT;
1816
1817 if (!SGEN_CAN_ALIGN_UP (size))
1818 return NULL;
1819
1820 #ifndef DISABLE_CRITICAL_REGION
1821 ENTER_CRITICAL_REGION;
1822 str = (MonoString*)sgen_try_alloc_obj_nolock (vtable, size);
1823 if (str) {
1824 /*This doesn't require fencing since EXIT_CRITICAL_REGION already does it for us*/
1825 str->length = len;
1826 EXIT_CRITICAL_REGION;
1827 goto done;
1828 }
1829 EXIT_CRITICAL_REGION;
1830 #endif
1831
1832 LOCK_GC;
1833
1834 str = (MonoString*)sgen_alloc_obj_nolock (vtable, size);
1835 if (G_UNLIKELY (!str)) {
1836 UNLOCK_GC;
1837 return NULL;
1838 }
1839
1840 str->length = len;
1841
1842 UNLOCK_GC;
1843
1844 done:
1845 if (G_UNLIKELY (alloc_events))
1846 mono_profiler_allocation (&str->object);
1847
1848 return str;
1849 }
1850
1851 /*
1852 * Strings
1853 */
1854
1855 void
1856 mono_gc_set_string_length (MonoString *str, gint32 new_length)
1857 {
1858 mono_unichar2 *new_end = str->chars + new_length;
1859
1860 /* zero the discarded string. This null-delimits the string and allows
1861 * the space to be reclaimed by SGen. */
1862
1863 if (nursery_canaries_enabled () && sgen_ptr_in_nursery (str)) {
1864 CHECK_CANARY_FOR_OBJECT ((GCObject*)str, TRUE);
1865 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2) + CANARY_SIZE);
1866 memcpy (new_end + 1 , CANARY_STRING, CANARY_SIZE);
1867 } else {
1868 memset (new_end, 0, (str->length - new_length + 1) * sizeof (mono_unichar2));
1869 }
1870
1871 str->length = new_length;
1872 }
1873
1874 /*
1875 * Profiling
1876 */
1877
1878 #define GC_ROOT_NUM 32
1879 typedef struct {
1880 int count; /* must be the first field */
1881 void *objects [GC_ROOT_NUM];
1882 int root_types [GC_ROOT_NUM];
1883 uintptr_t extra_info [GC_ROOT_NUM];
1884 } GCRootReport;
1885
1886 static void
1887 notify_gc_roots (GCRootReport *report)
1888 {
1889 if (!report->count)
1890 return;
1891 mono_profiler_gc_roots (report->count, report->objects, report->root_types, report->extra_info);
1892 report->count = 0;
1893 }
1894
1895 static void
1896 add_profile_gc_root (GCRootReport *report, void *object, int rtype, uintptr_t extra_info)
1897 {
1898 if (report->count == GC_ROOT_NUM)
1899 notify_gc_roots (report);
1900 report->objects [report->count] = object;
1901 report->root_types [report->count] = rtype;
1902 report->extra_info [report->count++] = (uintptr_t)SGEN_LOAD_VTABLE (object)->klass;
1903 }
1904
1905 void
1906 sgen_client_nursery_objects_pinned (void **definitely_pinned, int count)
1907 {
1908 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS) {
1909 GCRootReport report;
1910 int idx;
1911 report.count = 0;
1912 for (idx = 0; idx < count; ++idx)
1913 add_profile_gc_root (&report, definitely_pinned [idx], MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
1914 notify_gc_roots (&report);
1915 }
1916 }
1917
1918 static void
1919 report_finalizer_roots_from_queue (SgenPointerQueue *queue)
1920 {
1921 GCRootReport report;
1922 size_t i;
1923
1924 report.count = 0;
1925 for (i = 0; i < queue->next_slot; ++i) {
1926 void *obj = queue->data [i];
1927 if (!obj)
1928 continue;
1929 add_profile_gc_root (&report, obj, MONO_PROFILE_GC_ROOT_FINALIZER, 0);
1930 }
1931 notify_gc_roots (&report);
1932 }
1933
1934 static void
1935 report_finalizer_roots (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
1936 {
1937 report_finalizer_roots_from_queue (fin_ready_queue);
1938 report_finalizer_roots_from_queue (critical_fin_queue);
1939 }
1940
1941 static GCRootReport *root_report;
1942
1943 static void
1944 single_arg_report_root (MonoObject **obj, void *gc_data)
1945 {
1946 if (*obj)
1947 add_profile_gc_root (root_report, *obj, MONO_PROFILE_GC_ROOT_OTHER, 0);
1948 }
1949
1950 static void
1951 precisely_report_roots_from (GCRootReport *report, void** start_root, void** end_root, mword desc)
1952 {
1953 switch (desc & ROOT_DESC_TYPE_MASK) {
1954 case ROOT_DESC_BITMAP:
1955 desc >>= ROOT_DESC_TYPE_SHIFT;
1956 while (desc) {
1957 if ((desc & 1) && *start_root) {
1958 add_profile_gc_root (report, *start_root, MONO_PROFILE_GC_ROOT_OTHER, 0);
1959 }
1960 desc >>= 1;
1961 start_root++;
1962 }
1963 return;
1964 case ROOT_DESC_COMPLEX: {
1965 gsize *bitmap_data = (gsize *)sgen_get_complex_descriptor_bitmap (desc);
1966 gsize bwords = (*bitmap_data) - 1;
1967 void **start_run = start_root;
1968 bitmap_data++;
1969 while (bwords-- > 0) {
1970 gsize bmap = *bitmap_data++;
1971 void **objptr = start_run;
1972 while (bmap) {
1973 if ((bmap & 1) && *objptr) {
1974 add_profile_gc_root (report, *objptr, MONO_PROFILE_GC_ROOT_OTHER, 0);
1975 }
1976 bmap >>= 1;
1977 ++objptr;
1978 }
1979 start_run += GC_BITS_PER_WORD;
1980 }
1981 break;
1982 }
1983 case ROOT_DESC_USER: {
1984 MonoGCRootMarkFunc marker = (MonoGCRootMarkFunc)sgen_get_user_descriptor_func (desc);
1985 root_report = report;
1986 marker ((MonoObject**)start_root, single_arg_report_root, NULL);
1987 break;
1988 }
1989 case ROOT_DESC_RUN_LEN:
1990 g_assert_not_reached ();
1991 default:
1992 g_assert_not_reached ();
1993 }
1994 }
1995
1996 static void
1997 report_registered_roots_by_type (int root_type)
1998 {
1999 GCRootReport report;
2000 void **start_root;
2001 RootRecord *root;
2002 report.count = 0;
2003 SGEN_HASH_TABLE_FOREACH (&roots_hash [root_type], void **, start_root, RootRecord *, root) {
2004 SGEN_LOG (6, "Precise root scan %p-%p (desc: %p)", start_root, root->end_root, (void*)root->root_desc);
2005 precisely_report_roots_from (&report, start_root, (void**)root->end_root, root->root_desc);
2006 } SGEN_HASH_TABLE_FOREACH_END;
2007 notify_gc_roots (&report);
2008 }
2009
2010 static void
2011 report_registered_roots (void)
2012 {
2013 report_registered_roots_by_type (ROOT_TYPE_NORMAL);
2014 report_registered_roots_by_type (ROOT_TYPE_WBARRIER);
2015 }
2016
2017 void
2018 sgen_client_collecting_minor (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2019 {
2020 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2021 report_registered_roots ();
2022 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2023 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2024 }
2025
2026 static GCRootReport major_root_report;
2027 static gboolean profile_roots;
2028
2029 void
2030 sgen_client_collecting_major_1 (void)
2031 {
2032 profile_roots = mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS;
2033 memset (&major_root_report, 0, sizeof (GCRootReport));
2034 }
2035
2036 void
2037 sgen_client_pinned_los_object (GCObject *obj)
2038 {
2039 if (profile_roots)
2040 add_profile_gc_root (&major_root_report, (char*)obj, MONO_PROFILE_GC_ROOT_PINNING | MONO_PROFILE_GC_ROOT_MISC, 0);
2041 }
2042
2043 void
2044 sgen_client_collecting_major_2 (void)
2045 {
2046 if (profile_roots)
2047 notify_gc_roots (&major_root_report);
2048
2049 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2050 report_registered_roots ();
2051 }
2052
2053 void
2054 sgen_client_collecting_major_3 (SgenPointerQueue *fin_ready_queue, SgenPointerQueue *critical_fin_queue)
2055 {
2056 if (mono_profiler_get_events () & MONO_PROFILE_GC_ROOTS)
2057 report_finalizer_roots (fin_ready_queue, critical_fin_queue);
2058 }
2059
2060 #define MOVED_OBJECTS_NUM 64
2061 static void *moved_objects [MOVED_OBJECTS_NUM];
2062 static int moved_objects_idx = 0;
2063
2064 void
2065 mono_sgen_register_moved_object (void *obj, void *destination)
2066 {
2067 g_assert (mono_profiler_events & MONO_PROFILE_GC_MOVES);
2068
2069 if (moved_objects_idx == MOVED_OBJECTS_NUM) {
2070 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2071 moved_objects_idx = 0;
2072 }
2073 moved_objects [moved_objects_idx++] = obj;
2074 moved_objects [moved_objects_idx++] = destination;
2075 }
2076
2077 void
2078 mono_sgen_gc_event_moves (void)
2079 {
2080 if (moved_objects_idx) {
2081 mono_profiler_gc_moves (moved_objects, moved_objects_idx);
2082 moved_objects_idx = 0;
2083 }
2084 }
2085
2086 /*
2087 * Heap walking
2088 */
2089
2090 #define REFS_SIZE 128
2091 typedef struct {
2092 void *data;
2093 MonoGCReferences callback;
2094 int flags;
2095 int count;
2096 int called;
2097 MonoObject *refs [REFS_SIZE];
2098 uintptr_t offsets [REFS_SIZE];
2099 } HeapWalkInfo;
2100
2101 #undef HANDLE_PTR
2102 #define HANDLE_PTR(ptr,obj) do { \
2103 if (*(ptr)) { \
2104 if (hwi->count == REFS_SIZE) { \
2105 hwi->callback ((MonoObject*)start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data); \
2106 hwi->count = 0; \
2107 hwi->called = 1; \
2108 } \
2109 hwi->offsets [hwi->count] = (char*)(ptr)-(char*)start; \
2110 hwi->refs [hwi->count++] = *(ptr); \
2111 } \
2112 } while (0)
2113
2114 static void
2115 collect_references (HeapWalkInfo *hwi, GCObject *obj, size_t size)
2116 {
2117 char *start = (char*)obj;
2118 mword desc = sgen_obj_get_descriptor (obj);
2119
2120 #include "sgen/sgen-scan-object.h"
2121 }
2122
2123 static void
2124 walk_references (GCObject *start, size_t size, void *data)
2125 {
2126 HeapWalkInfo *hwi = (HeapWalkInfo *)data;
2127 hwi->called = 0;
2128 hwi->count = 0;
2129 collect_references (hwi, start, size);
2130 if (hwi->count || !hwi->called)
2131 hwi->callback (start, mono_object_class (start), hwi->called? 0: size, hwi->count, hwi->refs, hwi->offsets, hwi->data);
2132 }
2133
2134 /**
2135 * mono_gc_walk_heap:
2136 * @flags: flags for future use
2137 * @callback: a function pointer called for each object in the heap
2138 * @data: a user data pointer that is passed to callback
2139 *
2140 * This function can be used to iterate over all the live objects in the heap:
2141 * for each object, @callback is invoked, providing info about the object's
2142 * location in memory, its class, its size and the objects it references.
2143 * For each referenced object it's offset from the object address is
2144 * reported in the offsets array.
2145 * The object references may be buffered, so the callback may be invoked
2146 * multiple times for the same object: in all but the first call, the size
2147 * argument will be zero.
2148 * Note that this function can be only called in the #MONO_GC_EVENT_PRE_START_WORLD
2149 * profiler event handler.
2150 *
2151 * Returns: a non-zero value if the GC doesn't support heap walking
2152 */
2153 int
2154 mono_gc_walk_heap (int flags, MonoGCReferences callback, void *data)
2155 {
2156 HeapWalkInfo hwi;
2157
2158 hwi.flags = flags;
2159 hwi.callback = callback;
2160 hwi.data = data;
2161
2162 sgen_clear_nursery_fragments ();
2163 sgen_scan_area_with_callback (nursery_section->data, nursery_section->end_data, walk_references, &hwi, FALSE, TRUE);
2164
2165 major_collector.iterate_objects (ITERATE_OBJECTS_SWEEP_ALL, walk_references, &hwi);
2166 sgen_los_iterate_objects (walk_references, &hwi);
2167
2168 return 0;
2169 }
2170
2171 /*
2172 * Threads
2173 */
2174
2175 void
2176 mono_gc_set_gc_callbacks (MonoGCCallbacks *callbacks)
2177 {
2178 gc_callbacks = *callbacks;
2179 }
2180
2181 MonoGCCallbacks *
2182 mono_gc_get_gc_callbacks ()
2183 {
2184 return &gc_callbacks;
2185 }
2186
2187 void
2188 sgen_client_thread_register (SgenThreadInfo* info, void *stack_bottom_fallback)
2189 {
2190 size_t stsize = 0;
2191 guint8 *staddr = NULL;
2192
2193 #ifndef HAVE_KW_THREAD
2194 g_assert (!mono_native_tls_get_value (thread_info_key));
2195 mono_native_tls_set_value (thread_info_key, info);
2196 #else
2197 sgen_thread_info = info;
2198 #endif
2199
2200 info->client_info.skip = 0;
2201 info->client_info.stopped_ip = NULL;
2202 info->client_info.stopped_domain = NULL;
2203
2204 info->client_info.stack_start = NULL;
2205
2206 #ifdef SGEN_POSIX_STW
2207 info->client_info.stop_count = -1;
2208 info->client_info.signal = 0;
2209 #endif
2210
2211 /* On win32, stack_start_limit should be 0, since the stack can grow dynamically */
2212 mono_thread_info_get_stack_bounds (&staddr, &stsize);
2213 if (staddr) {
2214 #ifndef HOST_WIN32
2215 info->client_info.stack_start_limit = staddr;
2216 #endif
2217 info->client_info.stack_end = staddr + stsize;
2218 } else {
2219 gsize stack_bottom = (gsize)stack_bottom_fallback;
2220 stack_bottom += 4095;
2221 stack_bottom &= ~4095;
2222 info->client_info.stack_end = (char*)stack_bottom;
2223 }
2224
2225 memset (&info->client_info.ctx, 0, sizeof (MonoContext));
2226
2227 if (mono_gc_get_gc_callbacks ()->thread_attach_func)
2228 info->client_info.runtime_data = mono_gc_get_gc_callbacks ()->thread_attach_func ();
2229
2230 binary_protocol_thread_register ((gpointer)mono_thread_info_get_tid (info));
2231
2232 SGEN_LOG (3, "registered thread %p (%p) stack end %p", info, (gpointer)mono_thread_info_get_tid (info), info->client_info.stack_end);
2233
2234 info->client_info.info.handle_stack = mono_handle_stack_alloc ();
2235 }
2236
2237 void
2238 sgen_client_thread_unregister (SgenThreadInfo *p)
2239 {
2240 MonoNativeThreadId tid;
2241
2242 #ifndef HAVE_KW_THREAD
2243 mono_native_tls_set_value (thread_info_key, NULL);
2244 #else
2245 sgen_thread_info = NULL;
2246 #endif
2247
2248 tid = mono_thread_info_get_tid (p);
2249
2250 if (p->client_info.info.runtime_thread)
2251 mono_threads_add_joinable_thread ((gpointer)tid);
2252
2253 if (mono_gc_get_gc_callbacks ()->thread_detach_func) {
2254 mono_gc_get_gc_callbacks ()->thread_detach_func (p->client_info.runtime_data);
2255 p->client_info.runtime_data = NULL;
2256 }
2257
2258 binary_protocol_thread_unregister ((gpointer)tid);
2259 SGEN_LOG (3, "unregister thread %p (%p)", p, (gpointer)tid);
2260
2261 HandleStack *handles = (HandleStack*) p->client_info.info.handle_stack;
2262 p->client_info.info.handle_stack = NULL;
2263 mono_handle_stack_free (handles);
2264 }
2265
2266 void
2267 mono_gc_set_skip_thread (gboolean skip)
2268 {
2269 SgenThreadInfo *info = mono_thread_info_current ();
2270
2271 LOCK_GC;
2272 info->client_info.gc_disabled = skip;
2273 UNLOCK_GC;
2274 }
2275
2276 static gboolean
2277 is_critical_method (MonoMethod *method)
2278 {
2279 return mono_runtime_is_critical_method (method) || sgen_is_critical_method (method);
2280 }
2281
2282 static gboolean
2283 thread_in_critical_region (SgenThreadInfo *info)
2284 {
2285 return info->client_info.in_critical_region;
2286 }
2287
2288 static void
2289 sgen_thread_attach (SgenThreadInfo *info)
2290 {
2291 if (mono_gc_get_gc_callbacks ()->thread_attach_func && !info->client_info.runtime_data)
2292 info->client_info.runtime_data = mono_gc_get_gc_callbacks ()->thread_attach_func ();
2293 }
2294
2295 static void
2296 sgen_thread_detach (SgenThreadInfo *p)
2297 {
2298 /* If a delegate is passed to native code and invoked on a thread we dont
2299 * know about, marshal will register it with mono_threads_attach_coop, but
2300 * we have no way of knowing when that thread goes away. SGen has a TSD
2301 * so we assume that if the domain is still registered, we can detach
2302 * the thread
2303 */
2304 if (mono_domain_get ())
2305 mono_thread_detach_internal (mono_thread_internal_current ());
2306 }
2307
2308 gboolean
2309 mono_gc_register_thread (void *baseptr)
2310 {
2311 return mono_thread_info_attach (baseptr) != NULL;
2312 }
2313
2314 gboolean
2315 mono_gc_is_gc_thread (void)
2316 {
2317 gboolean result;
2318 LOCK_GC;
2319 result = mono_thread_info_current () != NULL;
2320 UNLOCK_GC;
2321 return result;
2322 }
2323
2324 void
2325 sgen_client_thread_register_worker (void)
2326 {
2327 mono_thread_info_register_small_id ();
2328 mono_native_thread_set_name (mono_native_thread_id_get (), "SGen worker");
2329 }
2330
2331 /* Variables holding start/end nursery so it won't have to be passed at every call */
2332 static void *scan_area_arg_start, *scan_area_arg_end;
2333
2334 void
2335 mono_gc_conservatively_scan_area (void *start, void *end)
2336 {
2337 sgen_conservatively_pin_objects_from ((void **)start, (void **)end, scan_area_arg_start, scan_area_arg_end, PIN_TYPE_STACK);
2338 }
2339
2340 void*
2341 mono_gc_scan_object (void *obj, void *gc_data)
2342 {
2343 ScanCopyContext *ctx = (ScanCopyContext *)gc_data;
2344 ctx->ops->copy_or_mark_object ((GCObject**)&obj, ctx->queue);
2345 return obj;
2346 }
2347
2348 /*
2349 * Mark from thread stacks and registers.
2350 */
2351 void
2352 sgen_client_scan_thread_data (void *start_nursery, void *end_nursery, gboolean precise, ScanCopyContext ctx)
2353 {
2354 scan_area_arg_start = start_nursery;
2355 scan_area_arg_end = end_nursery;
2356
2357 FOREACH_THREAD (info) {
2358 int skip_reason = 0;
2359 void *aligned_stack_start;
2360
2361 if (info->client_info.skip) {
2362 SGEN_LOG (3, "Skipping dead thread %p, range: %p-%p, size: %zd", info, info->client_info.stack_start, info->client_info.stack_end, (char*)info->client_info.stack_end - (char*)info->client_info.stack_start);
2363 skip_reason = 1;
2364 } else if (info->client_info.gc_disabled) {
2365 SGEN_LOG (3, "GC disabled for thread %p, range: %p-%p, size: %zd", info, info->client_info.stack_start, info->client_info.stack_end, (char*)info->client_info.stack_end - (char*)info->client_info.stack_start);
2366 skip_reason = 2;
2367 } else if (!mono_thread_info_is_live (info)) {
2368 SGEN_LOG (3, "Skipping non-running thread %p, range: %p-%p, size: %zd (state %x)", info, info->client_info.stack_start, info->client_info.stack_end, (char*)info->client_info.stack_end - (char*)info->client_info.stack_start, info->client_info.info.thread_state);
2369 skip_reason = 3;
2370 } else if (!info->client_info.stack_start) {
2371 SGEN_LOG (3, "Skipping starting or detaching thread %p", info);
2372 skip_reason = 4;
2373 }
2374
2375 binary_protocol_scan_stack ((gpointer)mono_thread_info_get_tid (info), info->client_info.stack_start, info->client_info.stack_end, skip_reason);
2376
2377 if (skip_reason)
2378 continue;
2379
2380 g_assert (info->client_info.stack_start);
2381 g_assert (info->client_info.stack_end);
2382
2383 aligned_stack_start = (void*)(mword) ALIGN_TO ((mword)info->client_info.stack_start, SIZEOF_VOID_P);
2384 #ifdef HOST_WIN32
2385 /* Windows uses a guard page before the committed stack memory pages to detect when the
2386 stack needs to be grown. If we suspend a thread just after a function prolog has
2387 decremented the stack pointer to point into the guard page but before the thread has
2388 been able to read or write to that page, starting the stack scan at aligned_stack_start
2389 will raise a STATUS_GUARD_PAGE_VIOLATION and the process will crash. This code uses
2390 VirtualQuery() to determine whether stack_start points into the guard page and then
2391 updates aligned_stack_start to point at the next non-guard page. */
2392 MEMORY_BASIC_INFORMATION mem_info;
2393 SIZE_T result = VirtualQuery(info->client_info.stack_start, &mem_info, sizeof(mem_info));
2394 g_assert (result != 0);
2395 if (mem_info.Protect & PAGE_GUARD) {
2396 aligned_stack_start = ((char*) mem_info.BaseAddress) + mem_info.RegionSize;
2397 }
2398 #endif
2399
2400 g_assert (info->client_info.suspend_done);
2401 SGEN_LOG (3, "Scanning thread %p, range: %p-%p, size: %zd, pinned=%zd", info, info->client_info.stack_start, info->client_info.stack_end, (char*)info->client_info.stack_end - (char*)info->client_info.stack_start, sgen_get_pinned_count ());
2402 if (mono_gc_get_gc_callbacks ()->thread_mark_func && !conservative_stack_mark) {
2403 mono_gc_get_gc_callbacks ()->thread_mark_func (info->client_info.runtime_data, (guint8 *)aligned_stack_start, (guint8 *)info->client_info.stack_end, precise, &ctx);
2404 } else if (!precise) {
2405 if (!conservative_stack_mark) {
2406 fprintf (stderr, "Precise stack mark not supported - disabling.\n");
2407 conservative_stack_mark = TRUE;
2408 }
2409 //FIXME we should eventually use the new stack_mark from coop
2410 sgen_conservatively_pin_objects_from ((void **)aligned_stack_start, (void **)info->client_info.stack_end, start_nursery, end_nursery, PIN_TYPE_STACK);
2411 }
2412
2413 if (!precise) {
2414 sgen_conservatively_pin_objects_from ((void**)&info->client_info.ctx, (void**)(&info->client_info.ctx + 1),
2415 start_nursery, end_nursery, PIN_TYPE_STACK);
2416
2417 {
2418 // This is used on Coop GC for platforms where we cannot get the data for individual registers.
2419 // We force a spill of all registers into the stack and pass a chunk of data into sgen.
2420 //FIXME under coop, for now, what we need to ensure is that we scan any extra memory from info->client_info.stack_end to stack_mark
2421 MonoThreadUnwindState *state = &info->client_info.info.thread_saved_state [SELF_SUSPEND_STATE_INDEX];
2422 if (state && state->gc_stackdata) {
2423 sgen_conservatively_pin_objects_from ((void **)state->gc_stackdata, (void**)((char*)state->gc_stackdata + state->gc_stackdata_size),
2424 start_nursery, end_nursery, PIN_TYPE_STACK);
2425 }
2426 }
2427 }
2428 if (precise && info->client_info.info.handle_stack) {
2429 mono_handle_stack_scan ((HandleStack*)info->client_info.info.handle_stack, (GcScanFunc)ctx.ops->copy_or_mark_object, ctx.queue);
2430 }
2431 } FOREACH_THREAD_END
2432 }
2433
2434 /*
2435 * mono_gc_set_stack_end:
2436 *
2437 * Set the end of the current threads stack to STACK_END. The stack space between
2438 * STACK_END and the real end of the threads stack will not be scanned during collections.
2439 */
2440 void
2441 mono_gc_set_stack_end (void *stack_end)
2442 {
2443 SgenThreadInfo *info;
2444
2445 LOCK_GC;
2446 info = mono_thread_info_current ();
2447 if (info) {
2448 SGEN_ASSERT (0, stack_end < info->client_info.stack_end, "Can only lower stack end");
2449 info->client_info.stack_end = stack_end;
2450 }
2451 UNLOCK_GC;
2452 }
2453
2454 /*
2455 * Roots
2456 */
2457
2458 int
2459 mono_gc_register_root (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2460 {
2461 return sgen_register_root (start, size, descr, descr ? ROOT_TYPE_NORMAL : ROOT_TYPE_PINNED, source, msg);
2462 }
2463
2464 int
2465 mono_gc_register_root_wbarrier (char *start, size_t size, MonoGCDescriptor descr, MonoGCRootSource source, const char *msg)
2466 {
2467 return sgen_register_root (start, size, descr, ROOT_TYPE_WBARRIER, source, msg);
2468 }
2469
2470 void
2471 mono_gc_deregister_root (char* addr)
2472 {
2473 sgen_deregister_root (addr);
2474 }
2475
2476 /*
2477 * PThreads
2478 */
2479
2480 #ifndef HOST_WIN32
2481 int
2482 mono_gc_pthread_create (pthread_t *new_thread, const pthread_attr_t *attr, void *(*start_routine)(void *), void *arg)
2483 {
2484 return pthread_create (new_thread, attr, start_routine, arg);
2485 }
2486 #endif
2487
2488 /*
2489 * Miscellaneous
2490 */
2491
2492 void
2493 sgen_client_total_allocated_heap_changed (size_t allocated_heap)
2494 {
2495 mono_runtime_resource_check_limit (MONO_RESOURCE_GC_HEAP, allocated_heap);
2496 }
2497
2498 gboolean
2499 mono_gc_user_markers_supported (void)
2500 {
2501 return TRUE;
2502 }
2503
2504 gboolean
2505 mono_object_is_alive (MonoObject* o)
2506 {
2507 return TRUE;
2508 }
2509
2510 int
2511 mono_gc_get_generation (MonoObject *obj)
2512 {
2513 if (sgen_ptr_in_nursery (obj))
2514 return 0;
2515 return 1;
2516 }
2517
2518 void
2519 mono_gc_enable_events (void)
2520 {
2521 }
2522
2523 const char *
2524 mono_gc_get_gc_name (void)
2525 {
2526 return "sgen";
2527 }
2528
2529 char*
2530 mono_gc_get_description (void)
2531 {
2532 #ifdef HAVE_CONC_GC_AS_DEFAULT
2533 return g_strdup ("sgen (concurrent by default)");
2534 #else
2535 return g_strdup ("sgen");
2536 #endif
2537 }
2538
2539 void
2540 mono_gc_set_desktop_mode (void)
2541 {
2542 }
2543
2544 gboolean
2545 mono_gc_is_moving (void)
2546 {
2547 return TRUE;
2548 }
2549
2550 gboolean
2551 mono_gc_is_disabled (void)
2552 {
2553 return FALSE;
2554 }
2555
2556 #ifdef HOST_WIN32
2557 BOOL APIENTRY mono_gc_dllmain (HMODULE module_handle, DWORD reason, LPVOID reserved)
2558 {
2559 return TRUE;
2560 }
2561 #endif
2562
2563 int
2564 mono_gc_max_generation (void)
2565 {
2566 return 1;
2567 }
2568
2569 gboolean
2570 mono_gc_precise_stack_mark_enabled (void)
2571 {
2572 return !conservative_stack_mark;
2573 }
2574
2575 void
2576 mono_gc_collect (int generation)
2577 {
2578 sgen_gc_collect (generation);
2579 }
2580
2581 int
2582 mono_gc_collection_count (int generation)
2583 {
2584 return sgen_gc_collection_count (generation);
2585 }
2586
2587 int64_t
2588 mono_gc_get_used_size (void)
2589 {
2590 return (int64_t)sgen_gc_get_used_size ();
2591 }
2592
2593 int64_t
2594 mono_gc_get_heap_size (void)
2595 {
2596 return (int64_t)sgen_gc_get_total_heap_allocation ();
2597 }
2598
2599 MonoGCDescriptor
2600 mono_gc_make_root_descr_user (MonoGCRootMarkFunc marker)
2601 {
2602 return sgen_make_user_root_descriptor (marker);
2603 }
2604
2605 MonoGCDescriptor
2606 mono_gc_make_descr_for_string (gsize *bitmap, int numbits)
2607 {
2608 return SGEN_DESC_STRING;
2609 }
2610
2611 void*
2612 mono_gc_get_nursery (int *shift_bits, size_t *size)
2613 {
2614 *size = sgen_nursery_size;
2615 *shift_bits = DEFAULT_NURSERY_BITS;
2616 return sgen_get_nursery_start ();
2617 }
2618
2619 int
2620 mono_gc_get_los_limit (void)
2621 {
2622 return SGEN_MAX_SMALL_OBJ_SIZE;
2623 }
2624
2625 gpointer
2626 sgen_client_default_metadata (void)
2627 {
2628 return mono_domain_get ();
2629 }
2630
2631 gpointer
2632 sgen_client_metadata_for_object (GCObject *obj)
2633 {
2634 return mono_object_domain (obj);
2635 }
2636
2637 /**
2638 * mono_gchandle_is_in_domain:
2639 * @gchandle: a GCHandle's handle.
2640 * @domain: An application domain.
2641 *
2642 * Returns: TRUE if the object wrapped by the @gchandle belongs to the specific @domain.
2643 */
2644 gboolean
2645 mono_gchandle_is_in_domain (guint32 gchandle, MonoDomain *domain)
2646 {
2647 MonoDomain *gchandle_domain = (MonoDomain *)sgen_gchandle_get_metadata (gchandle);
2648 return domain->domain_id == gchandle_domain->domain_id;
2649 }
2650
2651 /**
2652 * mono_gchandle_free_domain:
2653 * @unloading: domain that is unloading
2654 *
2655 * Function used internally to cleanup any GC handle for objects belonging
2656 * to the specified domain during appdomain unload.
2657 */
2658 void
2659 mono_gchandle_free_domain (MonoDomain *unloading)
2660 {
2661 }
2662
2663 static gpointer
2664 null_link_if_in_domain (gpointer hidden, GCHandleType handle_type, int max_generation, gpointer user)
2665 {
2666 MonoDomain *unloading_domain = (MonoDomain *)user;
2667 MonoDomain *obj_domain;
2668 gboolean is_weak = MONO_GC_HANDLE_TYPE_IS_WEAK (handle_type);
2669 if (MONO_GC_HANDLE_IS_OBJECT_POINTER (hidden)) {
2670 MonoObject *obj = (MonoObject *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2671 obj_domain = mono_object_domain (obj);
2672 } else {
2673 obj_domain = (MonoDomain *)MONO_GC_REVEAL_POINTER (hidden, is_weak);
2674 }
2675 if (unloading_domain->domain_id == obj_domain->domain_id)
2676 return NULL;
2677 return hidden;
2678 }
2679
2680 void
2681 sgen_null_links_for_domain (MonoDomain *domain)
2682 {
2683 guint type;
2684 for (type = HANDLE_TYPE_MIN; type < HANDLE_TYPE_MAX; ++type)
2685 sgen_gchandle_iterate ((GCHandleType)type, GENERATION_OLD, null_link_if_in_domain, domain);
2686 }
2687
2688 void
2689 mono_gchandle_set_target (guint32 gchandle, MonoObject *obj)
2690 {
2691 sgen_gchandle_set_target (gchandle, obj);
2692 }
2693
2694 void
2695 sgen_client_gchandle_created (int handle_type, GCObject *obj, guint32 handle)
2696 {
2697 #ifndef DISABLE_PERFCOUNTERS
2698 mono_perfcounters->gc_num_handles++;
2699 #endif
2700 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_CREATED, handle_type, handle, obj);
2701 }
2702
2703 void
2704 sgen_client_gchandle_destroyed (int handle_type, guint32 handle)
2705 {
2706 #ifndef DISABLE_PERFCOUNTERS
2707 mono_perfcounters->gc_num_handles--;
2708 #endif
2709 mono_profiler_gc_handle (MONO_PROFILER_GC_HANDLE_DESTROYED, handle_type, handle, NULL);
2710 }
2711
2712 void
2713 sgen_client_ensure_weak_gchandles_accessible (void)
2714 {
2715 /*
2716 * During the second bridge processing step the world is
2717 * running again. That step processes all weak links once
2718 * more to null those that refer to dead objects. Before that
2719 * is completed, those links must not be followed, so we
2720 * conservatively wait for bridge processing when any weak
2721 * link is dereferenced.
2722 */
2723 /* FIXME: A GC can occur after this check fails, in which case we
2724 * should wait for bridge processing but would fail to do so.
2725 */
2726 if (G_UNLIKELY (bridge_processing_in_progress))
2727 mono_gc_wait_for_bridge_processing ();
2728 }
2729
2730 void*
2731 mono_gc_invoke_with_gc_lock (MonoGCLockedCallbackFunc func, void *data)
2732 {
2733 void *result;
2734 LOCK_INTERRUPTION;
2735 result = func (data);
2736 UNLOCK_INTERRUPTION;
2737 return result;
2738 }
2739
2740 void
2741 mono_gc_register_altstack (gpointer stack, gint32 stack_size, gpointer altstack, gint32 altstack_size)
2742 {
2743 // FIXME:
2744 }
2745
2746 guint8*
2747 mono_gc_get_card_table (int *shift_bits, gpointer *mask)
2748 {
2749 return sgen_get_card_table_configuration (shift_bits, mask);
2750 }
2751
2752 gboolean
2753 mono_gc_card_table_nursery_check (void)
2754 {
2755 return !sgen_get_major_collector ()->is_concurrent;
2756 }
2757
2758 /* Negative value to remove */
2759 void
2760 mono_gc_add_memory_pressure (gint64 value)
2761 {
2762 /* FIXME: Implement at some point? */
2763 }
2764
2765 /*
2766 * Logging
2767 */
2768
2769 void
2770 sgen_client_degraded_allocation (size_t size)
2771 {
2772 static int last_major_gc_warned = -1;
2773 static int num_degraded = 0;
2774
2775 if (last_major_gc_warned < (int)gc_stats.major_gc_count) {
2776 ++num_degraded;
2777 if (num_degraded == 1 || num_degraded == 3)
2778 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Degraded allocation. Consider increasing nursery-size if the warning persists.");
2779 else if (num_degraded == 10)
2780 mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "Warning: Repeated degraded allocation. Consider increasing nursery-size.");
2781 last_major_gc_warned = gc_stats.major_gc_count;
2782 }
2783 }
2784
2785 /*
2786 * Debugging
2787 */
2788
2789 const char*
2790 sgen_client_description_for_internal_mem_type (int type)
2791 {
2792 switch (type) {
2793 case INTERNAL_MEM_EPHEMERON_LINK: return "ephemeron-link";
2794 default:
2795 return NULL;
2796 }
2797 }
2798
2799 void
2800 sgen_client_pre_collection_checks (void)
2801 {
2802 if (sgen_mono_xdomain_checks) {
2803 sgen_clear_nursery_fragments ();
2804 sgen_check_for_xdomain_refs ();
2805 }
2806 }
2807
2808 gboolean
2809 sgen_client_vtable_is_inited (MonoVTable *vt)
2810 {
2811 return vt->klass->inited;
2812 }
2813
2814 const char*
2815 sgen_client_vtable_get_namespace (MonoVTable *vt)
2816 {
2817 return vt->klass->name_space;
2818 }
2819
2820 const char*
2821 sgen_client_vtable_get_name (MonoVTable *vt)
2822 {
2823 return vt->klass->name;
2824 }
2825
2826 /*
2827 * Initialization
2828 */
2829
2830 void
2831 sgen_client_init (void)
2832 {
2833 int dummy;
2834 MonoThreadInfoCallbacks cb;
2835
2836 cb.thread_register = sgen_thread_register;
2837 cb.thread_detach = sgen_thread_detach;
2838 cb.thread_unregister = sgen_thread_unregister;
2839 cb.thread_attach = sgen_thread_attach;
2840 cb.mono_method_is_critical = (gboolean (*)(void *))is_critical_method;
2841 cb.mono_thread_in_critical_region = thread_in_critical_region;
2842
2843 mono_threads_init (&cb, sizeof (SgenThreadInfo));
2844
2845 ///* Keep this the default for now */
2846 /* Precise marking is broken on all supported targets. Disable until fixed. */
2847 conservative_stack_mark = TRUE;
2848
2849 sgen_register_fixed_internal_mem_type (INTERNAL_MEM_EPHEMERON_LINK, sizeof (EphemeronLinkNode));
2850
2851 mono_sgen_init_stw ();
2852
2853 #ifndef HAVE_KW_THREAD
2854 mono_native_tls_alloc (&thread_info_key, NULL);
2855 #if defined(TARGET_OSX) || defined(TARGET_WIN32) || defined(TARGET_ANDROID) || defined(TARGET_IOS)
2856 /*
2857 * CEE_MONO_TLS requires the tls offset, not the key, so the code below only works on darwin,
2858 * where the two are the same.
2859 */
2860 mono_tls_key_set_offset (TLS_KEY_SGEN_THREAD_INFO, thread_info_key);
2861 #endif
2862 #else
2863 {
2864 int tls_offset = -1;
2865 MONO_THREAD_VAR_OFFSET (sgen_thread_info, tls_offset);
2866 mono_tls_key_set_offset (TLS_KEY_SGEN_THREAD_INFO, tls_offset);
2867 }
2868 #endif
2869
2870 /*
2871 * This needs to happen before any internal allocations because
2872 * it inits the small id which is required for hazard pointer
2873 * operations.
2874 */
2875 sgen_os_init ();
2876
2877 mono_gc_register_thread (&dummy);
2878 }
2879
2880 gboolean
2881 sgen_client_handle_gc_param (const char *opt)
2882 {
2883 if (g_str_has_prefix (opt, "stack-mark=")) {
2884 opt = strchr (opt, '=') + 1;
2885 if (!strcmp (opt, "precise")) {
2886 conservative_stack_mark = FALSE;
2887 } else if (!strcmp (opt, "conservative")) {
2888 conservative_stack_mark = TRUE;
2889 } else {
2890 sgen_env_var_error (MONO_GC_PARAMS_NAME, conservative_stack_mark ? "Using `conservative`." : "Using `precise`.",
2891 "Invalid value `%s` for `stack-mark` option, possible values are: `precise`, `conservative`.", opt);
2892 }
2893 } else if (g_str_has_prefix (opt, "bridge-implementation=")) {
2894 opt = strchr (opt, '=') + 1;
2895 sgen_set_bridge_implementation (opt);
2896 } else if (g_str_has_prefix (opt, "toggleref-test")) {
2897 /* FIXME: This should probably in MONO_GC_DEBUG */
2898 sgen_register_test_toggleref_callback ();
2899 } else if (!sgen_bridge_handle_gc_param (opt)) {
2900 return FALSE;
2901 }
2902 return TRUE;
2903 }
2904
2905 void
2906 sgen_client_print_gc_params_usage (void)
2907 {
2908 fprintf (stderr, " stack-mark=MARK-METHOD (where MARK-METHOD is 'precise' or 'conservative')\n");
2909 }
2910
2911 gboolean
2912 sgen_client_handle_gc_debug (const char *opt)
2913 {
2914 if (!strcmp (opt, "xdomain-checks")) {
2915 sgen_mono_xdomain_checks = TRUE;
2916 } else if (!strcmp (opt, "do-not-finalize")) {
2917 mono_do_not_finalize = TRUE;
2918 } else if (g_str_has_prefix (opt, "do-not-finalize=")) {
2919 opt = strchr (opt, '=') + 1;
2920 mono_do_not_finalize = TRUE;
2921 mono_do_not_finalize_class_names = g_strsplit (opt, ",", 0);
2922 } else if (!strcmp (opt, "log-finalizers")) {
2923 log_finalizers = TRUE;
2924 } else if (!strcmp (opt, "no-managed-allocator")) {
2925 sgen_set_use_managed_allocator (FALSE);
2926 } else if (!sgen_bridge_handle_gc_debug (opt)) {
2927 return FALSE;
2928 }
2929 return TRUE;
2930 }
2931
2932 void
2933 sgen_client_print_gc_debug_usage (void)
2934 {
2935 fprintf (stderr, " xdomain-checks\n");
2936 fprintf (stderr, " do-not-finalize\n");
2937 fprintf (stderr, " log-finalizers\n");
2938 fprintf (stderr, " no-managed-allocator\n");
2939 sgen_bridge_print_gc_debug_usage ();
2940 }
2941
2942
2943 gpointer
2944 sgen_client_get_provenance (void)
2945 {
2946 #ifdef SGEN_OBJECT_PROVENANCE
2947 MonoGCCallbacks *cb = mono_gc_get_gc_callbacks ();
2948 gpointer (*get_provenance_func) (void);
2949 if (!cb)
2950 return NULL;
2951 get_provenance_func = cb->get_provenance_func;
2952 if (get_provenance_func)
2953 return get_provenance_func ();
2954 return NULL;
2955 #else
2956 return NULL;
2957 #endif
2958 }
2959
2960 void
2961 sgen_client_describe_invalid_pointer (GCObject *ptr)
2962 {
2963 sgen_bridge_describe_pointer (ptr);
2964 }
2965
2966 static gboolean gc_inited;
2967
2968 void
2969 mono_gc_base_init (void)
2970 {
2971 if (gc_inited)
2972 return;
2973
2974 mono_counters_init ();
2975
2976 #ifdef HEAVY_STATISTICS
2977 mono_counters_register ("los marked cards", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_marked_cards);
2978 mono_counters_register ("los array cards scanned ", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_cards);
2979 mono_counters_register ("los array remsets", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &los_array_remsets);
2980
2981 mono_counters_register ("WBarrier set arrayref", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_set_arrayref);
2982 mono_counters_register ("WBarrier value copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_value_copy);
2983 mono_counters_register ("WBarrier object copy", MONO_COUNTER_GC | MONO_COUNTER_ULONG, &stat_wbarrier_object_copy);
2984 #endif
2985
2986 sgen_gc_init ();
2987
2988 if (nursery_canaries_enabled ())
2989 sgen_set_use_managed_allocator (FALSE);
2990
2991 #if defined(HAVE_KW_THREAD)
2992 /* This can happen with using libmonosgen.so */
2993 if (mono_tls_key_get_offset (TLS_KEY_SGEN_THREAD_INFO) == -1)
2994 sgen_set_use_managed_allocator (FALSE);
2995 #endif
2996
2997 gc_inited = TRUE;
2998 }
2999
3000 void
3001 mono_gc_base_cleanup (void)
3002 {
3003 sgen_thread_pool_shutdown ();
3004 }
3005
3006 gboolean
3007 mono_gc_is_null (void)
3008 {
3009 return FALSE;
3010 }
3011
3012 #endif
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