mono/metadata/sgen-bridge.c

   1 /*
   2  * sgen-bridge.c: Simple generational GC.
   3  *
   4  * Copyright 2011 Novell, Inc (http://www.novell.com)
   5  * Copyright 2011 Xamarin Inc (http://www.xamarin.com)
   6  *
   7  * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
   8  * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
   9  *
  10  * Permission is hereby granted to use or copy this program
  11  * for any purpose,  provided the above notices are retained on all copies.
  12  * Permission to modify the code and to distribute modified code is granted,
  13  * provided the above notices are retained, and a notice that the code was
  14  * modified is included with the above copyright notice.
  15  *
  16  *
  17  * Copyright 2001-2003 Ximian, Inc
  18  * Copyright 2003-2010 Novell, Inc.
  19  *
  20  * Permission is hereby granted, free of charge, to any person obtaining
  21  * a copy of this software and associated documentation files (the
  22  * "Software"), to deal in the Software without restriction, including
  23  * without limitation the rights to use, copy, modify, merge, publish,
  24  * distribute, sublicense, and/or sell copies of the Software, and to
  25  * permit persons to whom the Software is furnished to do so, subject to
  26  * the following conditions:
  27  *
  28  * The above copyright notice and this permission notice shall be
  29  * included in all copies or substantial portions of the Software.
  30  *
  31  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  32  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  33  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  34  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  35  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  36  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  37  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  38  */
  39
  40 #include "config.h"
  41
  42 #ifdef HAVE_SGEN_GC
  43
  44 #include <stdlib.h>
  45
  46 #include "sgen-gc.h"
  47 #include "sgen-bridge.h"
  48 #include "utils/mono-logger-internal.h"
  49 #include "utils/mono-time.h"
  50
  51
  52 typedef struct {
  53         int size;
  54         int elem_size;
  55         int capacity;
  56         char *data;
  57 } DynArray;
  58
  59 #define DYN_ARRAY_REF(da,i)     ((void*)((da)->data + (i) * (da)->elem_size))
  60 #define DYN_ARRAY_PTR_REF(da,i) (((void**)(da)->data) [(i)])
  61 #define DYN_ARRAY_INT_REF(da,i) (((int*)(da)->data) [(i)])
  62 #define DYN_ARRAY_PTR_STATIC_INITIALIZER { 0, sizeof (void*), 0, NULL }
  63 #define DYN_ARRAY_INT_STATIC_INITIALIZER { 0, sizeof (int), 0, NULL }
  64
  65 static void
  66 dyn_array_init (DynArray *da, int elem_size)
  67 {
  68         da->size = 0;
  69         da->elem_size = elem_size;
  70         da->capacity = 0;
  71         da->data = NULL;
  72 }
  73
  74 static void
  75 dyn_array_ptr_init (DynArray *da)
  76 {
  77         dyn_array_init (da, sizeof (void*));
  78 }
  79
  80 static void
  81 dyn_array_int_init (DynArray *da)
  82 {
  83         dyn_array_init (da, sizeof (int));
  84 }
  85
  86 static void
  87 dyn_array_uninit (DynArray *da)
  88 {
  89         if (da->capacity <= 0)
  90                 return;
  91
  92         mono_sgen_free_internal_dynamic (da->data, da->elem_size * da->capacity, INTERNAL_MEM_BRIDGE_DATA);
  93         da->data = NULL;
  94 }
  95
  96 static void
  97 dyn_array_ensure_capacity (DynArray *da, int capacity)
  98 {
  99         int old_capacity = da->capacity;
 100         char *new_data;
 101
 102         if (capacity <= old_capacity)
 103                 return;
 104
 105         if (da->capacity == 0)
 106                 da->capacity = 2;
 107         while (capacity > da->capacity)
 108                 da->capacity *= 2;
 109
 110         new_data = mono_sgen_alloc_internal_dynamic (da->elem_size * da->capacity, INTERNAL_MEM_BRIDGE_DATA);
 111         memcpy (new_data, da->data, da->elem_size * da->size);
 112         mono_sgen_free_internal_dynamic (da->data, da->elem_size * old_capacity, INTERNAL_MEM_BRIDGE_DATA);
 113         da->data = new_data;
 114 }
 115
 116 static void*
 117 dyn_array_add (DynArray *da)
 118 {
 119         void *p;
 120
 121         dyn_array_ensure_capacity (da, da->size + 1);
 122
 123         p = DYN_ARRAY_REF (da, da->size);
 124         ++da->size;
 125         return p;
 126 }
 127
 128 static void
 129 dyn_array_ptr_add (DynArray *da, void *ptr)
 130 {
 131         void **p = dyn_array_add (da);
 132         *p = ptr;
 133 }
 134
 135 #define dyn_array_ptr_push dyn_array_ptr_add
 136
 137 static void*
 138 dyn_array_ptr_pop (DynArray *da)
 139 {
 140         void *p;
 141         g_assert (da->size > 0);
 142         p = DYN_ARRAY_PTR_REF (da, da->size - 1);
 143         --da->size;
 144         return p;
 145 }
 146
 147 static void
 148 dyn_array_int_add (DynArray *da, int x)
 149 {
 150         int *p = dyn_array_add (da);
 151         *p = x;
 152 }
 153
 154 /*
 155 static gboolean
 156 dyn_array_ptr_contains (DynArray *da, void *ptr)
 157 {
 158         int i;
 159         for (i = 0; i < da->size; ++i)
 160                 if (DYN_ARRAY_PTR_REF (da, i) == ptr)
 161                         return TRUE;
 162         return FALSE;
 163 }
 164 */
 165
 166 static gboolean
 167 dyn_array_int_contains (DynArray *da, int x)
 168 {
 169         int i;
 170         for (i = 0; i < da->size; ++i)
 171                 if (DYN_ARRAY_INT_REF (da, i) == x)
 172                         return TRUE;
 173         return FALSE;
 174 }
 175
 176 static DynArray merge_array;
 177
 178 static void
 179 dyn_array_int_merge (DynArray *dst, DynArray *src)
 180 {
 181         int i, j;
 182
 183         dyn_array_ensure_capacity (&merge_array, dst->size + src->size);
 184         merge_array.size = 0;
 185
 186         for (i = j = 0; i < dst->size || j < src->size; ) {
 187                 if (i < dst->size && j < src->size) {
 188                         int a = DYN_ARRAY_INT_REF (dst, i);
 189                         int b = DYN_ARRAY_INT_REF (src, j);
 190                         if (a < b) {
 191                                 dyn_array_int_add (&merge_array, a);
 192                                 ++i;
 193                         } else if (a == b) {
 194                                 dyn_array_int_add (&merge_array, a);
 195                                 ++i;
 196                                 ++j;
 197                         } else {
 198                                 dyn_array_int_add (&merge_array, b);
 199                                 ++j;
 200                         }
 201                 } else if (i < dst->size) {
 202                         dyn_array_int_add (&merge_array, DYN_ARRAY_INT_REF (dst, i));
 203                         ++i;
 204                 } else {
 205                         dyn_array_int_add (&merge_array, DYN_ARRAY_INT_REF (src, j));
 206                         ++j;
 207                 }
 208         }
 209
 210         if (merge_array.size > dst->size) {
 211                 dyn_array_ensure_capacity (dst, merge_array.size);
 212                 memcpy (DYN_ARRAY_REF (dst, 0), DYN_ARRAY_REF (&merge_array, 0), merge_array.size * merge_array.elem_size);
 213                 dst->size = merge_array.size;
 214         }
 215 }
 216
 217 static void
 218 dyn_array_int_merge_one (DynArray *array, int value)
 219 {
 220         int i;
 221         int tmp;
 222         int end = array->size;
 223
 224         for (i = 0; i < end; ++i) {
 225                 if (DYN_ARRAY_INT_REF (array, i) == value)
 226                         return;
 227                 else if (DYN_ARRAY_INT_REF (array, i) > value)
 228                         break;
 229         }
 230
 231         dyn_array_ensure_capacity (array, array->size + 1);
 232
 233         if (i < end) {
 234                 tmp = DYN_ARRAY_INT_REF (array, i);
 235                 for (; i <= end; ++i) {
 236                         DYN_ARRAY_INT_REF (array, i) = value;
 237                         value = tmp;
 238                         tmp = DYN_ARRAY_INT_REF (array, i + 1);
 239                 }
 240                 DYN_ARRAY_INT_REF (array, end + 1) = tmp;
 241         } else {
 242                 DYN_ARRAY_INT_REF (array, end) = value;
 243         }
 244         ++array->size;
 245 }
 246
 247 /*
 248  * FIXME: Optimizations:
 249  *
 250  * Don't allocate a scrs array for just one source.  Most objects have
 251  * just one source, so use the srcs pointer itself.
 252  */
 253 typedef struct _HashEntry {
 254         MonoObject *obj;        /* This is a duplicate - it's already stored in the hash table */
 255
 256         gboolean is_bridge;
 257         gboolean is_visited;
 258
 259         int finishing_time;
 260
 261         DynArray srcs;
 262
 263         int scc_index;
 264 } HashEntry;
 265
 266 typedef struct _SCC {
 267         int index;
 268         int api_index;
 269         int num_bridge_entries;
 270         DynArray xrefs;         /* these are incoming, not outgoing */
 271 } SCC;
 272
 273 static SgenHashTable hash_table = SGEN_HASH_TABLE_INIT (INTERNAL_MEM_BRIDGE_DATA, INTERNAL_MEM_BRIDGE_DATA, sizeof (HashEntry), mono_aligned_addr_hash, NULL);
 274
 275 static MonoGCBridgeCallbacks bridge_callbacks;
 276
 277 static int current_time;
 278
 279 void
 280 mono_gc_register_bridge_callbacks (MonoGCBridgeCallbacks *callbacks)
 281 {
 282         bridge_callbacks = *callbacks;
 283 }
 284
 285 gboolean
 286 mono_sgen_is_bridge_object (MonoObject *obj)
 287 {
 288         return bridge_callbacks.is_bridge_object (obj);
 289 }
 290
 291 gboolean
 292 mono_sgen_need_bridge_processing (void)
 293 {
 294         return bridge_callbacks.cross_references != NULL;
 295 }
 296
 297 static HashEntry*
 298 get_hash_entry (MonoObject *obj, gboolean *existing)
 299 {
 300         HashEntry *entry = mono_sgen_hash_table_lookup (&hash_table, obj);
 301         HashEntry new_entry;
 302
 303         if (entry) {
 304                 if (existing)
 305                         *existing = TRUE;
 306                 return entry;
 307         }
 308         if (existing)
 309                 *existing = FALSE;
 310
 311         memset (&new_entry, 0, sizeof (HashEntry));
 312
 313         new_entry.obj = obj;
 314         dyn_array_ptr_init (&new_entry.srcs);
 315         new_entry.finishing_time = -1;
 316         new_entry.scc_index = -1;
 317
 318         mono_sgen_hash_table_replace (&hash_table, obj, &new_entry);
 319
 320         return mono_sgen_hash_table_lookup (&hash_table, obj);
 321 }
 322
 323 static void
 324 add_source (HashEntry *entry, HashEntry *src)
 325 {
 326         dyn_array_ptr_add (&entry->srcs, src);
 327 }
 328
 329 static void
 330 free_data (void)
 331 {
 332         MonoObject *obj;
 333         HashEntry *entry;
 334         int total_srcs = 0;
 335         int max_srcs = 0;
 336
 337         SGEN_HASH_TABLE_FOREACH (&hash_table, obj, entry) {
 338                 total_srcs += entry->srcs.size;
 339                 if (entry->srcs.size > max_srcs)
 340                         max_srcs = entry->srcs.size;
 341                 dyn_array_uninit (&entry->srcs);
 342         } SGEN_HASH_TABLE_FOREACH_END;
 343
 344         mono_sgen_hash_table_clean (&hash_table);
 345
 346         dyn_array_uninit (&merge_array);
 347         //g_print ("total srcs %d - max %d\n", total_srcs, max_srcs);
 348 }
 349
 350 static HashEntry*
 351 register_bridge_object (MonoObject *obj)
 352 {
 353         HashEntry *entry = get_hash_entry (obj, NULL);
 354         entry->is_bridge = TRUE;
 355         return entry;
 356 }
 357
 358 static void
 359 register_finishing_time (HashEntry *entry, int t)
 360 {
 361         g_assert (entry->finishing_time < 0);
 362         entry->finishing_time = t;
 363 }
 364
 365 static gboolean
 366 object_is_live (MonoObject **objp)
 367 {
 368         MonoObject *obj = *objp;
 369         MonoObject *fwd = SGEN_OBJECT_IS_FORWARDED (obj);
 370         if (fwd) {
 371                 *objp = fwd;
 372                 return mono_sgen_hash_table_lookup (&hash_table, fwd) == NULL;
 373         }
 374         if (!mono_sgen_object_is_live (obj))
 375                 return FALSE;
 376         return mono_sgen_hash_table_lookup (&hash_table, obj) == NULL;
 377 }
 378
 379 static DynArray registered_bridges = DYN_ARRAY_PTR_STATIC_INITIALIZER;
 380 static DynArray dfs_stack;
 381
 382 static int dsf1_passes, dsf2_passes;
 383
 384
 385 #undef HANDLE_PTR
 386 #define HANDLE_PTR(ptr,obj)     do {                                    \
 387                 MonoObject *dst = (MonoObject*)*(ptr);                  \
 388                 if (dst && !object_is_live (&dst)) {                    \
 389                         dyn_array_ptr_push (&dfs_stack, obj_entry);     \
 390                         dyn_array_ptr_push (&dfs_stack, get_hash_entry (dst, NULL)); \
 391                 }                                                       \
 392         } while (0)
 393
 394 static void
 395 dfs1 (HashEntry *obj_entry, HashEntry *src)
 396 {
 397         g_assert (dfs_stack.size == 0);
 398
 399         dyn_array_ptr_push (&dfs_stack, src);
 400         dyn_array_ptr_push (&dfs_stack, obj_entry);
 401
 402         do {
 403                 MonoObject *obj;
 404                 char *start;
 405                 ++dsf1_passes;
 406
 407                 obj_entry = dyn_array_ptr_pop (&dfs_stack);
 408                 if (obj_entry) {
 409                         src = dyn_array_ptr_pop (&dfs_stack);
 410
 411                         obj = obj_entry->obj;
 412                         start = (char*)obj;
 413
 414                         if (src) {
 415                                 //g_print ("link %s -> %s\n", mono_sgen_safe_name (src->obj), mono_sgen_safe_name (obj));
 416                                 add_source (obj_entry, src);
 417                         } else {
 418                                 //g_print ("starting with %s\n", mono_sgen_safe_name (obj));
 419                         }
 420
 421                         if (obj_entry->is_visited)
 422                                 continue;
 423
 424                         obj_entry->is_visited = TRUE;
 425
 426                         dyn_array_ptr_push (&dfs_stack, obj_entry);
 427                         /* NULL marks that the next entry is to be finished */
 428                         dyn_array_ptr_push (&dfs_stack, NULL);
 429
 430 #include "sgen-scan-object.h"
 431                 } else {
 432                         obj_entry = dyn_array_ptr_pop (&dfs_stack);
 433
 434                         //g_print ("finish %s\n", mono_sgen_safe_name (obj_entry->obj));
 435                         register_finishing_time (obj_entry, current_time++);
 436                 }
 437         } while (dfs_stack.size > 0);
 438 }
 439
 440 static void
 441 scc_add_xref (SCC *src, SCC *dst)
 442 {
 443         g_assert (src != dst);
 444         g_assert (src->index != dst->index);
 445
 446         if (dyn_array_int_contains (&dst->xrefs, src->index))
 447                 return;
 448         if (src->num_bridge_entries) {
 449                 dyn_array_int_merge_one (&dst->xrefs, src->index);
 450         } else {
 451                 int i;
 452                 dyn_array_int_merge (&dst->xrefs, &src->xrefs);
 453                 for (i = 0; i < dst->xrefs.size; ++i)
 454                         g_assert (DYN_ARRAY_INT_REF (&dst->xrefs, i) != dst->index);
 455         }
 456 }
 457
 458 static void
 459 scc_add_entry (SCC *scc, HashEntry *entry)
 460 {
 461         g_assert (entry->scc_index < 0);
 462         entry->scc_index = scc->index;
 463         if (entry->is_bridge)
 464                 ++scc->num_bridge_entries;
 465 }
 466
 467 static DynArray sccs;
 468 static SCC *current_scc;
 469
 470 static void
 471 dfs2 (HashEntry *entry)
 472 {
 473         int i;
 474
 475         g_assert (dfs_stack.size == 0);
 476
 477         dyn_array_ptr_push (&dfs_stack, entry);
 478
 479         do {
 480                 entry = dyn_array_ptr_pop (&dfs_stack);
 481                 ++dsf2_passes;
 482
 483                 if (entry->scc_index >= 0) {
 484                         if (entry->scc_index != current_scc->index)
 485                                 scc_add_xref (DYN_ARRAY_REF (&sccs, entry->scc_index), current_scc);
 486                         continue;
 487                 }
 488
 489                 scc_add_entry (current_scc, entry);
 490
 491                 for (i = 0; i < entry->srcs.size; ++i)
 492                         dyn_array_ptr_push (&dfs_stack, DYN_ARRAY_PTR_REF (&entry->srcs, i));
 493         } while (dfs_stack.size > 0);
 494 }
 495
 496 static int
 497 compare_hash_entries (const void *ep1, const void *ep2)
 498 {
 499         HashEntry *e1 = *(HashEntry**)ep1;
 500         HashEntry *e2 = *(HashEntry**)ep2;
 501         return e2->finishing_time - e1->finishing_time;
 502 }
 503
 504 static unsigned long step_1, step_2, step_3, step_4, step_5, step_6, step_7, step_8;
 505 static int fist_pass_links, second_pass_links, sccs_links;
 506 static int max_sccs_links = 0;
 507
 508 void
 509 mono_sgen_bridge_register_finalized_object (MonoObject *obj)
 510 {
 511         g_assert (mono_sgen_need_bridge_processing ());
 512         dyn_array_ptr_push (&registered_bridges, obj);
 513 }
 514
 515 void
 516 mono_sgen_bridge_reset_data (void)
 517 {
 518         registered_bridges.size = 0;
 519 }
 520
 521 void
 522 mono_sgen_bridge_processing_stw_step (void)
 523 {
 524         int i;
 525         SGEN_TV_DECLARE (atv);
 526         SGEN_TV_DECLARE (btv);
 527
 528         if (!registered_bridges.size)
 529                 return;
 530
 531         SGEN_TV_GETTIME (btv);
 532
 533         /* first DFS pass */
 534
 535         dyn_array_ptr_init (&dfs_stack);
 536         dyn_array_int_init (&merge_array);
 537
 538         current_time = 0;
 539         for (i = 0; i < registered_bridges.size; ++i)
 540                 dfs1 (register_bridge_object (DYN_ARRAY_PTR_REF (&registered_bridges, i)), NULL);
 541
 542         SGEN_TV_GETTIME (atv);
 543         step_2 = SGEN_TV_ELAPSED (btv, atv);
 544 }
 545
 546 void
 547 mono_sgen_bridge_processing_finish (void)
 548 {
 549         int i, j;
 550         int num_sccs, num_xrefs;
 551         int max_entries, max_xrefs;
 552         int hash_table_size, sccs_size;
 553         MonoObject *obj;
 554         HashEntry *entry;
 555         int num_registered_bridges;
 556         HashEntry **all_entries;
 557         MonoGCBridgeSCC **api_sccs;
 558         MonoGCBridgeXRef *api_xrefs;
 559         SGEN_TV_DECLARE (atv);
 560         SGEN_TV_DECLARE (btv);
 561
 562         if (!registered_bridges.size)
 563                 return;
 564
 565         SGEN_TV_GETTIME (atv);
 566
 567         /* alloc and fill array of all entries */
 568
 569         all_entries = mono_sgen_alloc_internal_dynamic (sizeof (HashEntry*) * hash_table.num_entries, INTERNAL_MEM_BRIDGE_DATA);
 570
 571         j = 0;
 572         SGEN_HASH_TABLE_FOREACH (&hash_table, obj, entry) {
 573                 g_assert (entry->finishing_time >= 0);
 574                 all_entries [j++] = entry;
 575                 fist_pass_links += entry->srcs.size;
 576         } SGEN_HASH_TABLE_FOREACH_END;
 577         g_assert (j == hash_table.num_entries);
 578         hash_table_size = hash_table.num_entries;
 579
 580         /* sort array according to decreasing finishing time */
 581
 582         qsort (all_entries, hash_table.num_entries, sizeof (HashEntry*), compare_hash_entries);
 583
 584         SGEN_TV_GETTIME (btv);
 585         step_3 = SGEN_TV_ELAPSED (atv, btv);
 586
 587         /* second DFS pass */
 588
 589         dyn_array_init (&sccs, sizeof (SCC));
 590         for (i = 0; i < hash_table.num_entries; ++i) {
 591                 HashEntry *entry = all_entries [i];
 592                 if (entry->scc_index < 0) {
 593                         int index = sccs.size;
 594                         current_scc = dyn_array_add (&sccs);
 595                         current_scc->index = index;
 596                         current_scc->num_bridge_entries = 0;
 597                         current_scc->api_index = -1;
 598                         dyn_array_int_init (&current_scc->xrefs);
 599
 600                         dfs2 (entry);
 601                 }
 602         }
 603
 604         sccs_size = sccs.size;
 605
 606         for (i = 0; i < hash_table.num_entries; ++i) {
 607                 HashEntry *entry = all_entries [i];
 608                 second_pass_links += entry->srcs.size;
 609         }
 610
 611         SGEN_TV_GETTIME (atv);
 612         step_4 = SGEN_TV_ELAPSED (btv, atv);
 613
 614         //g_print ("%d sccs\n", sccs.size);
 615
 616         dyn_array_uninit (&dfs_stack);
 617
 618         /* init data for callback */
 619
 620         num_sccs = 0;
 621         for (i = 0; i < sccs.size; ++i) {
 622                 SCC *scc = DYN_ARRAY_REF (&sccs, i);
 623                 g_assert (scc->index == i);
 624                 if (scc->num_bridge_entries)
 625                         ++num_sccs;
 626                 sccs_links += scc->xrefs.size;
 627                 max_sccs_links = MAX (max_sccs_links, scc->xrefs.size);
 628         }
 629
 630         api_sccs = mono_sgen_alloc_internal_dynamic (sizeof (MonoGCBridgeSCC*) * num_sccs, INTERNAL_MEM_BRIDGE_DATA);
 631         num_xrefs = 0;
 632         j = 0;
 633         for (i = 0; i < sccs.size; ++i) {
 634                 SCC *scc = DYN_ARRAY_REF (&sccs, i);
 635                 if (!scc->num_bridge_entries)
 636                         continue;
 637
 638                 api_sccs [j] = mono_sgen_alloc_internal_dynamic (sizeof (MonoGCBridgeSCC) + sizeof (MonoObject*) * scc->num_bridge_entries, INTERNAL_MEM_BRIDGE_DATA);
 639                 api_sccs [j]->num_objs = scc->num_bridge_entries;
 640                 scc->num_bridge_entries = 0;
 641                 scc->api_index = j++;
 642
 643                 num_xrefs += scc->xrefs.size;
 644         }
 645
 646         SGEN_HASH_TABLE_FOREACH (&hash_table, obj, entry) {
 647                 if (entry->is_bridge) {
 648                         SCC *scc = DYN_ARRAY_REF (&sccs, entry->scc_index);
 649                         api_sccs [scc->api_index]->objs [scc->num_bridge_entries++] = entry->obj;
 650                 }
 651         } SGEN_HASH_TABLE_FOREACH_END;
 652
 653         api_xrefs = mono_sgen_alloc_internal_dynamic (sizeof (MonoGCBridgeXRef) * num_xrefs, INTERNAL_MEM_BRIDGE_DATA);
 654         j = 0;
 655         for (i = 0; i < sccs.size; ++i) {
 656                 int k;
 657                 SCC *scc = DYN_ARRAY_REF (&sccs, i);
 658                 if (!scc->num_bridge_entries)
 659                         continue;
 660                 for (k = 0; k < scc->xrefs.size; ++k) {
 661                         SCC *src_scc = DYN_ARRAY_REF (&sccs, DYN_ARRAY_INT_REF (&scc->xrefs, k));
 662                         if (!src_scc->num_bridge_entries)
 663                                 continue;
 664                         api_xrefs [j].src_scc_index = src_scc->api_index;
 665                         api_xrefs [j].dst_scc_index = scc->api_index;
 666                         ++j;
 667                 }
 668         }
 669
 670         SGEN_TV_GETTIME (btv);
 671         step_5 = SGEN_TV_ELAPSED (atv, btv);
 672
 673         /* free data */
 674
 675         j = 0;
 676         max_entries = max_xrefs = 0;
 677         for (i = 0; i < sccs.size; ++i) {
 678                 SCC *scc = DYN_ARRAY_REF (&sccs, i);
 679                 if (scc->num_bridge_entries)
 680                         ++j;
 681                 if (scc->num_bridge_entries > max_entries)
 682                         max_entries = scc->num_bridge_entries;
 683                 if (scc->xrefs.size > max_xrefs)
 684                         max_xrefs = scc->xrefs.size;
 685                 dyn_array_uninit (&scc->xrefs);
 686
 687         }
 688         dyn_array_uninit (&sccs);
 689
 690         mono_sgen_free_internal_dynamic (all_entries, sizeof (HashEntry*) * hash_table.num_entries, INTERNAL_MEM_BRIDGE_DATA);
 691
 692         free_data ();
 693         /* Empty the registered bridges array */
 694         num_registered_bridges = registered_bridges.size;
 695         registered_bridges.size = 0;
 696
 697         SGEN_TV_GETTIME (atv);
 698         step_6 = SGEN_TV_ELAPSED (btv, atv);
 699
 700         //g_print ("%d sccs containing bridges - %d max bridge objects - %d max xrefs\n", j, max_entries, max_xrefs);
 701
 702         /* callback */
 703
 704         bridge_callbacks.cross_references (num_sccs, api_sccs, num_xrefs, api_xrefs);
 705
 706 /*Release for finalization those objects we no longer care. */
 707         SGEN_TV_GETTIME (btv);
 708         step_7 = SGEN_TV_ELAPSED (atv, btv);
 709
 710         for (i = 0; i < num_sccs; ++i) {
 711                 if (!api_sccs [i]->objs [0])
 712                         continue;
 713                 for (j = 0; j < api_sccs [i]->num_objs; ++j)
 714                         mono_sgen_mark_bridge_object (api_sccs [i]->objs [j]);
 715         }
 716
 717         /* free callback data */
 718
 719         for (i = 0; i < num_sccs; ++i) {
 720                 mono_sgen_free_internal_dynamic (api_sccs [i],
 721                                 sizeof (MonoGCBridgeSCC) + sizeof (MonoObject*) * api_sccs [i]->num_objs,
 722                                 INTERNAL_MEM_BRIDGE_DATA);
 723         }
 724         mono_sgen_free_internal_dynamic (api_sccs, sizeof (MonoGCBridgeSCC*) * num_sccs, INTERNAL_MEM_BRIDGE_DATA);
 725
 726         mono_sgen_free_internal_dynamic (api_xrefs, sizeof (MonoGCBridgeXRef) * num_xrefs, INTERNAL_MEM_BRIDGE_DATA);
 727
 728         SGEN_TV_GETTIME (atv);
 729         step_8 = SGEN_TV_ELAPSED (btv, atv);
 730
 731         mono_trace (G_LOG_LEVEL_INFO, MONO_TRACE_GC, "GC_BRIDGE num-objects %d num_hash_entries %d sccs size %d init %.2fms df1 %.2fms sort %.2fms dfs2 %.2fms setup-cb %.2fms free-data %.2fms user-cb %.2fms clenanup %.2fms links %d/%d/%d/%d dfs passes %d/%d",
 732                 num_registered_bridges, hash_table_size, sccs.size,
 733                 step_1 / 1000.0f,
 734                 step_2 / 1000.0f,
 735                 step_3 / 1000.0f,
 736                 step_4 / 1000.0f,
 737                 step_5 / 1000.0f,
 738                 step_6 / 1000.0f,
 739                 step_7 / 1000.0f,
 740                 step_8 / 1000.f,
 741                 fist_pass_links, second_pass_links, sccs_links, max_sccs_links,
 742                 dsf1_passes, dsf2_passes);
 743
 744         step_1 = 0; /* We must cleanup since this value is used as an accumulator. */
 745 }
 746
 747 static const char *bridge_class;
 748
 749 static gboolean
 750 bridge_test_is_bridge_object (MonoObject *obj)
 751 {
 752         return !strcmp (bridge_class, obj->vtable->klass->name);
 753 }
 754
 755 static void
 756 bridge_test_cross_reference (int num_sccs, MonoGCBridgeSCC **sccs, int num_xrefs, MonoGCBridgeXRef *xrefs)
 757 {
 758         int i;
 759         for (i = 0; i < num_sccs; ++i) {
 760                 int j;
 761         //      g_print ("--- SCC %d\n", i);
 762                 for (j = 0; j < sccs [i]->num_objs; ++j) {
 763         //              g_print ("  %s\n", mono_sgen_safe_name (sccs [i]->objs [j]));
 764                         if (i & 1) /*retain half of the bridged objects */
 765                                 sccs [i]->objs [0] = NULL;
 766                 }
 767         }
 768         for (i = 0; i < num_xrefs; ++i) {
 769                 g_assert (xrefs [i].src_scc_index >= 0 && xrefs [i].src_scc_index < num_sccs);
 770                 g_assert (xrefs [i].dst_scc_index >= 0 && xrefs [i].dst_scc_index < num_sccs);
 771         //      g_print ("%d -> %d\n", xrefs [i].src_scc_index, xrefs [i].dst_scc_index);
 772         }
 773 }
 774
 775
 776 void
 777 mono_sgen_register_test_bridge_callbacks (const char *bridge_class_name)
 778 {
 779         MonoGCBridgeCallbacks callbacks;
 780         callbacks.is_bridge_object = bridge_test_is_bridge_object;
 781         callbacks.cross_references = bridge_test_cross_reference;
 782         mono_gc_register_bridge_callbacks (&callbacks);
 783         bridge_class = bridge_class_name;
 784 }
 785
 786 #endif