1 // Copyright 2013 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "src/profiler/heap-snapshot-generator.h"
6
7 #include "src/code-stubs.h"
8 #include "src/conversions.h"
9 #include "src/debug/debug.h"
10 #include "src/objects-body-descriptors.h"
11 #include "src/profiler/allocation-tracker.h"
12 #include "src/profiler/heap-profiler.h"
13 #include "src/profiler/heap-snapshot-generator-inl.h"
14
15 namespace v8 {
16 namespace internal {
17
18
HeapGraphEdge(Type type,const char * name,int from,int to)19 HeapGraphEdge::HeapGraphEdge(Type type, const char* name, int from, int to)
20 : bit_field_(TypeField::encode(type) | FromIndexField::encode(from)),
21 to_index_(to),
22 name_(name) {
23 DCHECK(type == kContextVariable
24 || type == kProperty
25 || type == kInternal
26 || type == kShortcut
27 || type == kWeak);
28 }
29
30
HeapGraphEdge(Type type,int index,int from,int to)31 HeapGraphEdge::HeapGraphEdge(Type type, int index, int from, int to)
32 : bit_field_(TypeField::encode(type) | FromIndexField::encode(from)),
33 to_index_(to),
34 index_(index) {
35 DCHECK(type == kElement || type == kHidden);
36 }
37
38
ReplaceToIndexWithEntry(HeapSnapshot * snapshot)39 void HeapGraphEdge::ReplaceToIndexWithEntry(HeapSnapshot* snapshot) {
40 to_entry_ = &snapshot->entries()[to_index_];
41 }
42
43
44 const int HeapEntry::kNoEntry = -1;
45
HeapEntry(HeapSnapshot * snapshot,Type type,const char * name,SnapshotObjectId id,size_t self_size,unsigned trace_node_id)46 HeapEntry::HeapEntry(HeapSnapshot* snapshot,
47 Type type,
48 const char* name,
49 SnapshotObjectId id,
50 size_t self_size,
51 unsigned trace_node_id)
52 : type_(type),
53 children_count_(0),
54 children_index_(-1),
55 self_size_(self_size),
56 snapshot_(snapshot),
57 name_(name),
58 id_(id),
59 trace_node_id_(trace_node_id) { }
60
61
SetNamedReference(HeapGraphEdge::Type type,const char * name,HeapEntry * entry)62 void HeapEntry::SetNamedReference(HeapGraphEdge::Type type,
63 const char* name,
64 HeapEntry* entry) {
65 HeapGraphEdge edge(type, name, this->index(), entry->index());
66 snapshot_->edges().Add(edge);
67 ++children_count_;
68 }
69
70
SetIndexedReference(HeapGraphEdge::Type type,int index,HeapEntry * entry)71 void HeapEntry::SetIndexedReference(HeapGraphEdge::Type type,
72 int index,
73 HeapEntry* entry) {
74 HeapGraphEdge edge(type, index, this->index(), entry->index());
75 snapshot_->edges().Add(edge);
76 ++children_count_;
77 }
78
79
Print(const char * prefix,const char * edge_name,int max_depth,int indent)80 void HeapEntry::Print(
81 const char* prefix, const char* edge_name, int max_depth, int indent) {
82 STATIC_ASSERT(sizeof(unsigned) == sizeof(id()));
83 base::OS::Print("%6" PRIuS " @%6u %*c %s%s: ", self_size(), id(), indent, ' ',
84 prefix, edge_name);
85 if (type() != kString) {
86 base::OS::Print("%s %.40s\n", TypeAsString(), name_);
87 } else {
88 base::OS::Print("\"");
89 const char* c = name_;
90 while (*c && (c - name_) <= 40) {
91 if (*c != '\n')
92 base::OS::Print("%c", *c);
93 else
94 base::OS::Print("\\n");
95 ++c;
96 }
97 base::OS::Print("\"\n");
98 }
99 if (--max_depth == 0) return;
100 Vector<HeapGraphEdge*> ch = children();
101 for (int i = 0; i < ch.length(); ++i) {
102 HeapGraphEdge& edge = *ch[i];
103 const char* edge_prefix = "";
104 EmbeddedVector<char, 64> index;
105 const char* edge_name = index.start();
106 switch (edge.type()) {
107 case HeapGraphEdge::kContextVariable:
108 edge_prefix = "#";
109 edge_name = edge.name();
110 break;
111 case HeapGraphEdge::kElement:
112 SNPrintF(index, "%d", edge.index());
113 break;
114 case HeapGraphEdge::kInternal:
115 edge_prefix = "$";
116 edge_name = edge.name();
117 break;
118 case HeapGraphEdge::kProperty:
119 edge_name = edge.name();
120 break;
121 case HeapGraphEdge::kHidden:
122 edge_prefix = "$";
123 SNPrintF(index, "%d", edge.index());
124 break;
125 case HeapGraphEdge::kShortcut:
126 edge_prefix = "^";
127 edge_name = edge.name();
128 break;
129 case HeapGraphEdge::kWeak:
130 edge_prefix = "w";
131 edge_name = edge.name();
132 break;
133 default:
134 SNPrintF(index, "!!! unknown edge type: %d ", edge.type());
135 }
136 edge.to()->Print(edge_prefix, edge_name, max_depth, indent + 2);
137 }
138 }
139
140
TypeAsString()141 const char* HeapEntry::TypeAsString() {
142 switch (type()) {
143 case kHidden: return "/hidden/";
144 case kObject: return "/object/";
145 case kClosure: return "/closure/";
146 case kString: return "/string/";
147 case kCode: return "/code/";
148 case kArray: return "/array/";
149 case kRegExp: return "/regexp/";
150 case kHeapNumber: return "/number/";
151 case kNative: return "/native/";
152 case kSynthetic: return "/synthetic/";
153 case kConsString: return "/concatenated string/";
154 case kSlicedString: return "/sliced string/";
155 case kSymbol: return "/symbol/";
156 case kSimdValue: return "/simd/";
157 default: return "???";
158 }
159 }
160
161
162 // It is very important to keep objects that form a heap snapshot
163 // as small as possible.
164 namespace { // Avoid littering the global namespace.
165
166 template <size_t ptr_size> struct SnapshotSizeConstants;
167
168 template <> struct SnapshotSizeConstants<4> {
169 static const int kExpectedHeapGraphEdgeSize = 12;
170 static const int kExpectedHeapEntrySize = 28;
171 };
172
173 template <> struct SnapshotSizeConstants<8> {
174 static const int kExpectedHeapGraphEdgeSize = 24;
175 static const int kExpectedHeapEntrySize = 40;
176 };
177
178 } // namespace
179
180
HeapSnapshot(HeapProfiler * profiler)181 HeapSnapshot::HeapSnapshot(HeapProfiler* profiler)
182 : profiler_(profiler),
183 root_index_(HeapEntry::kNoEntry),
184 gc_roots_index_(HeapEntry::kNoEntry),
185 max_snapshot_js_object_id_(0) {
186 STATIC_ASSERT(
187 sizeof(HeapGraphEdge) ==
188 SnapshotSizeConstants<kPointerSize>::kExpectedHeapGraphEdgeSize);
189 STATIC_ASSERT(
190 sizeof(HeapEntry) ==
191 SnapshotSizeConstants<kPointerSize>::kExpectedHeapEntrySize);
192 USE(SnapshotSizeConstants<4>::kExpectedHeapGraphEdgeSize);
193 USE(SnapshotSizeConstants<4>::kExpectedHeapEntrySize);
194 USE(SnapshotSizeConstants<8>::kExpectedHeapGraphEdgeSize);
195 USE(SnapshotSizeConstants<8>::kExpectedHeapEntrySize);
196 for (int i = 0; i < VisitorSynchronization::kNumberOfSyncTags; ++i) {
197 gc_subroot_indexes_[i] = HeapEntry::kNoEntry;
198 }
199 }
200
201
Delete()202 void HeapSnapshot::Delete() {
203 profiler_->RemoveSnapshot(this);
204 delete this;
205 }
206
207
RememberLastJSObjectId()208 void HeapSnapshot::RememberLastJSObjectId() {
209 max_snapshot_js_object_id_ = profiler_->heap_object_map()->last_assigned_id();
210 }
211
212
AddSyntheticRootEntries()213 void HeapSnapshot::AddSyntheticRootEntries() {
214 AddRootEntry();
215 AddGcRootsEntry();
216 SnapshotObjectId id = HeapObjectsMap::kGcRootsFirstSubrootId;
217 for (int tag = 0; tag < VisitorSynchronization::kNumberOfSyncTags; tag++) {
218 AddGcSubrootEntry(tag, id);
219 id += HeapObjectsMap::kObjectIdStep;
220 }
221 DCHECK(HeapObjectsMap::kFirstAvailableObjectId == id);
222 }
223
224
AddRootEntry()225 HeapEntry* HeapSnapshot::AddRootEntry() {
226 DCHECK(root_index_ == HeapEntry::kNoEntry);
227 DCHECK(entries_.is_empty()); // Root entry must be the first one.
228 HeapEntry* entry = AddEntry(HeapEntry::kSynthetic,
229 "",
230 HeapObjectsMap::kInternalRootObjectId,
231 0,
232 0);
233 root_index_ = entry->index();
234 DCHECK(root_index_ == 0);
235 return entry;
236 }
237
238
AddGcRootsEntry()239 HeapEntry* HeapSnapshot::AddGcRootsEntry() {
240 DCHECK(gc_roots_index_ == HeapEntry::kNoEntry);
241 HeapEntry* entry = AddEntry(HeapEntry::kSynthetic,
242 "(GC roots)",
243 HeapObjectsMap::kGcRootsObjectId,
244 0,
245 0);
246 gc_roots_index_ = entry->index();
247 return entry;
248 }
249
250
AddGcSubrootEntry(int tag,SnapshotObjectId id)251 HeapEntry* HeapSnapshot::AddGcSubrootEntry(int tag, SnapshotObjectId id) {
252 DCHECK(gc_subroot_indexes_[tag] == HeapEntry::kNoEntry);
253 DCHECK(0 <= tag && tag < VisitorSynchronization::kNumberOfSyncTags);
254 HeapEntry* entry = AddEntry(HeapEntry::kSynthetic,
255 VisitorSynchronization::kTagNames[tag], id, 0, 0);
256 gc_subroot_indexes_[tag] = entry->index();
257 return entry;
258 }
259
260
AddEntry(HeapEntry::Type type,const char * name,SnapshotObjectId id,size_t size,unsigned trace_node_id)261 HeapEntry* HeapSnapshot::AddEntry(HeapEntry::Type type,
262 const char* name,
263 SnapshotObjectId id,
264 size_t size,
265 unsigned trace_node_id) {
266 HeapEntry entry(this, type, name, id, size, trace_node_id);
267 entries_.Add(entry);
268 return &entries_.last();
269 }
270
271
FillChildren()272 void HeapSnapshot::FillChildren() {
273 DCHECK(children().is_empty());
274 children().Allocate(edges().length());
275 int children_index = 0;
276 for (int i = 0; i < entries().length(); ++i) {
277 HeapEntry* entry = &entries()[i];
278 children_index = entry->set_children_index(children_index);
279 }
280 DCHECK(edges().length() == children_index);
281 for (int i = 0; i < edges().length(); ++i) {
282 HeapGraphEdge* edge = &edges()[i];
283 edge->ReplaceToIndexWithEntry(this);
284 edge->from()->add_child(edge);
285 }
286 }
287
288
289 class FindEntryById {
290 public:
FindEntryById(SnapshotObjectId id)291 explicit FindEntryById(SnapshotObjectId id) : id_(id) { }
operator ()(HeapEntry * const * entry)292 int operator()(HeapEntry* const* entry) {
293 if ((*entry)->id() == id_) return 0;
294 return (*entry)->id() < id_ ? -1 : 1;
295 }
296 private:
297 SnapshotObjectId id_;
298 };
299
300
GetEntryById(SnapshotObjectId id)301 HeapEntry* HeapSnapshot::GetEntryById(SnapshotObjectId id) {
302 List<HeapEntry*>* entries_by_id = GetSortedEntriesList();
303 // Perform a binary search by id.
304 int index = SortedListBSearch(*entries_by_id, FindEntryById(id));
305 if (index == -1)
306 return NULL;
307 return entries_by_id->at(index);
308 }
309
310
311 template<class T>
SortByIds(const T * entry1_ptr,const T * entry2_ptr)312 static int SortByIds(const T* entry1_ptr,
313 const T* entry2_ptr) {
314 if ((*entry1_ptr)->id() == (*entry2_ptr)->id()) return 0;
315 return (*entry1_ptr)->id() < (*entry2_ptr)->id() ? -1 : 1;
316 }
317
318
GetSortedEntriesList()319 List<HeapEntry*>* HeapSnapshot::GetSortedEntriesList() {
320 if (sorted_entries_.is_empty()) {
321 sorted_entries_.Allocate(entries_.length());
322 for (int i = 0; i < entries_.length(); ++i) {
323 sorted_entries_[i] = &entries_[i];
324 }
325 sorted_entries_.Sort<int (*)(HeapEntry* const*, HeapEntry* const*)>(
326 SortByIds);
327 }
328 return &sorted_entries_;
329 }
330
331
Print(int max_depth)332 void HeapSnapshot::Print(int max_depth) {
333 root()->Print("", "", max_depth, 0);
334 }
335
336
RawSnapshotSize() const337 size_t HeapSnapshot::RawSnapshotSize() const {
338 return
339 sizeof(*this) +
340 GetMemoryUsedByList(entries_) +
341 GetMemoryUsedByList(edges_) +
342 GetMemoryUsedByList(children_) +
343 GetMemoryUsedByList(sorted_entries_);
344 }
345
346
347 // We split IDs on evens for embedder objects (see
348 // HeapObjectsMap::GenerateId) and odds for native objects.
349 const SnapshotObjectId HeapObjectsMap::kInternalRootObjectId = 1;
350 const SnapshotObjectId HeapObjectsMap::kGcRootsObjectId =
351 HeapObjectsMap::kInternalRootObjectId + HeapObjectsMap::kObjectIdStep;
352 const SnapshotObjectId HeapObjectsMap::kGcRootsFirstSubrootId =
353 HeapObjectsMap::kGcRootsObjectId + HeapObjectsMap::kObjectIdStep;
354 const SnapshotObjectId HeapObjectsMap::kFirstAvailableObjectId =
355 HeapObjectsMap::kGcRootsFirstSubrootId +
356 VisitorSynchronization::kNumberOfSyncTags * HeapObjectsMap::kObjectIdStep;
357
HeapObjectsMap(Heap * heap)358 HeapObjectsMap::HeapObjectsMap(Heap* heap)
359 : next_id_(kFirstAvailableObjectId), heap_(heap) {
360 // This dummy element solves a problem with entries_map_.
361 // When we do lookup in HashMap we see no difference between two cases:
362 // it has an entry with NULL as the value or it has created
363 // a new entry on the fly with NULL as the default value.
364 // With such dummy element we have a guaranty that all entries_map_ entries
365 // will have the value field grater than 0.
366 // This fact is using in MoveObject method.
367 entries_.Add(EntryInfo(0, NULL, 0));
368 }
369
370
MoveObject(Address from,Address to,int object_size)371 bool HeapObjectsMap::MoveObject(Address from, Address to, int object_size) {
372 DCHECK(to != NULL);
373 DCHECK(from != NULL);
374 if (from == to) return false;
375 void* from_value = entries_map_.Remove(from, ComputePointerHash(from));
376 if (from_value == NULL) {
377 // It may occur that some untracked object moves to an address X and there
378 // is a tracked object at that address. In this case we should remove the
379 // entry as we know that the object has died.
380 void* to_value = entries_map_.Remove(to, ComputePointerHash(to));
381 if (to_value != NULL) {
382 int to_entry_info_index =
383 static_cast<int>(reinterpret_cast<intptr_t>(to_value));
384 entries_.at(to_entry_info_index).addr = NULL;
385 }
386 } else {
387 base::HashMap::Entry* to_entry =
388 entries_map_.LookupOrInsert(to, ComputePointerHash(to));
389 if (to_entry->value != NULL) {
390 // We found the existing entry with to address for an old object.
391 // Without this operation we will have two EntryInfo's with the same
392 // value in addr field. It is bad because later at RemoveDeadEntries
393 // one of this entry will be removed with the corresponding entries_map_
394 // entry.
395 int to_entry_info_index =
396 static_cast<int>(reinterpret_cast<intptr_t>(to_entry->value));
397 entries_.at(to_entry_info_index).addr = NULL;
398 }
399 int from_entry_info_index =
400 static_cast<int>(reinterpret_cast<intptr_t>(from_value));
401 entries_.at(from_entry_info_index).addr = to;
402 // Size of an object can change during its life, so to keep information
403 // about the object in entries_ consistent, we have to adjust size when the
404 // object is migrated.
405 if (FLAG_heap_profiler_trace_objects) {
406 PrintF("Move object from %p to %p old size %6d new size %6d\n",
407 static_cast<void*>(from), static_cast<void*>(to),
408 entries_.at(from_entry_info_index).size, object_size);
409 }
410 entries_.at(from_entry_info_index).size = object_size;
411 to_entry->value = from_value;
412 }
413 return from_value != NULL;
414 }
415
416
UpdateObjectSize(Address addr,int size)417 void HeapObjectsMap::UpdateObjectSize(Address addr, int size) {
418 FindOrAddEntry(addr, size, false);
419 }
420
421
FindEntry(Address addr)422 SnapshotObjectId HeapObjectsMap::FindEntry(Address addr) {
423 base::HashMap::Entry* entry =
424 entries_map_.Lookup(addr, ComputePointerHash(addr));
425 if (entry == NULL) return 0;
426 int entry_index = static_cast<int>(reinterpret_cast<intptr_t>(entry->value));
427 EntryInfo& entry_info = entries_.at(entry_index);
428 DCHECK(static_cast<uint32_t>(entries_.length()) > entries_map_.occupancy());
429 return entry_info.id;
430 }
431
432
FindOrAddEntry(Address addr,unsigned int size,bool accessed)433 SnapshotObjectId HeapObjectsMap::FindOrAddEntry(Address addr,
434 unsigned int size,
435 bool accessed) {
436 DCHECK(static_cast<uint32_t>(entries_.length()) > entries_map_.occupancy());
437 base::HashMap::Entry* entry =
438 entries_map_.LookupOrInsert(addr, ComputePointerHash(addr));
439 if (entry->value != NULL) {
440 int entry_index =
441 static_cast<int>(reinterpret_cast<intptr_t>(entry->value));
442 EntryInfo& entry_info = entries_.at(entry_index);
443 entry_info.accessed = accessed;
444 if (FLAG_heap_profiler_trace_objects) {
445 PrintF("Update object size : %p with old size %d and new size %d\n",
446 static_cast<void*>(addr), entry_info.size, size);
447 }
448 entry_info.size = size;
449 return entry_info.id;
450 }
451 entry->value = reinterpret_cast<void*>(entries_.length());
452 SnapshotObjectId id = next_id_;
453 next_id_ += kObjectIdStep;
454 entries_.Add(EntryInfo(id, addr, size, accessed));
455 DCHECK(static_cast<uint32_t>(entries_.length()) > entries_map_.occupancy());
456 return id;
457 }
458
459
StopHeapObjectsTracking()460 void HeapObjectsMap::StopHeapObjectsTracking() {
461 time_intervals_.Clear();
462 }
463
464
UpdateHeapObjectsMap()465 void HeapObjectsMap::UpdateHeapObjectsMap() {
466 if (FLAG_heap_profiler_trace_objects) {
467 PrintF("Begin HeapObjectsMap::UpdateHeapObjectsMap. map has %d entries.\n",
468 entries_map_.occupancy());
469 }
470 heap_->CollectAllGarbage(Heap::kMakeHeapIterableMask,
471 GarbageCollectionReason::kHeapProfiler);
472 HeapIterator iterator(heap_);
473 for (HeapObject* obj = iterator.next();
474 obj != NULL;
475 obj = iterator.next()) {
476 FindOrAddEntry(obj->address(), obj->Size());
477 if (FLAG_heap_profiler_trace_objects) {
478 PrintF("Update object : %p %6d. Next address is %p\n",
479 static_cast<void*>(obj->address()), obj->Size(),
480 static_cast<void*>(obj->address() + obj->Size()));
481 }
482 }
483 RemoveDeadEntries();
484 if (FLAG_heap_profiler_trace_objects) {
485 PrintF("End HeapObjectsMap::UpdateHeapObjectsMap. map has %d entries.\n",
486 entries_map_.occupancy());
487 }
488 }
489
490
491 namespace {
492
493
494 struct HeapObjectInfo {
HeapObjectInfov8::internal::__anon5e8b875a0211::HeapObjectInfo495 HeapObjectInfo(HeapObject* obj, int expected_size)
496 : obj(obj),
497 expected_size(expected_size) {
498 }
499
500 HeapObject* obj;
501 int expected_size;
502
IsValidv8::internal::__anon5e8b875a0211::HeapObjectInfo503 bool IsValid() const { return expected_size == obj->Size(); }
504
Printv8::internal::__anon5e8b875a0211::HeapObjectInfo505 void Print() const {
506 if (expected_size == 0) {
507 PrintF("Untracked object : %p %6d. Next address is %p\n",
508 static_cast<void*>(obj->address()), obj->Size(),
509 static_cast<void*>(obj->address() + obj->Size()));
510 } else if (obj->Size() != expected_size) {
511 PrintF("Wrong size %6d: %p %6d. Next address is %p\n", expected_size,
512 static_cast<void*>(obj->address()), obj->Size(),
513 static_cast<void*>(obj->address() + obj->Size()));
514 } else {
515 PrintF("Good object : %p %6d. Next address is %p\n",
516 static_cast<void*>(obj->address()), expected_size,
517 static_cast<void*>(obj->address() + obj->Size()));
518 }
519 }
520 };
521
522
comparator(const HeapObjectInfo * a,const HeapObjectInfo * b)523 static int comparator(const HeapObjectInfo* a, const HeapObjectInfo* b) {
524 if (a->obj < b->obj) return -1;
525 if (a->obj > b->obj) return 1;
526 return 0;
527 }
528
529
530 } // namespace
531
532
FindUntrackedObjects()533 int HeapObjectsMap::FindUntrackedObjects() {
534 List<HeapObjectInfo> heap_objects(1000);
535
536 HeapIterator iterator(heap_);
537 int untracked = 0;
538 for (HeapObject* obj = iterator.next();
539 obj != NULL;
540 obj = iterator.next()) {
541 base::HashMap::Entry* entry =
542 entries_map_.Lookup(obj->address(), ComputePointerHash(obj->address()));
543 if (entry == NULL) {
544 ++untracked;
545 if (FLAG_heap_profiler_trace_objects) {
546 heap_objects.Add(HeapObjectInfo(obj, 0));
547 }
548 } else {
549 int entry_index = static_cast<int>(
550 reinterpret_cast<intptr_t>(entry->value));
551 EntryInfo& entry_info = entries_.at(entry_index);
552 if (FLAG_heap_profiler_trace_objects) {
553 heap_objects.Add(HeapObjectInfo(obj,
554 static_cast<int>(entry_info.size)));
555 if (obj->Size() != static_cast<int>(entry_info.size))
556 ++untracked;
557 } else {
558 CHECK_EQ(obj->Size(), static_cast<int>(entry_info.size));
559 }
560 }
561 }
562 if (FLAG_heap_profiler_trace_objects) {
563 PrintF("\nBegin HeapObjectsMap::FindUntrackedObjects. %d entries in map.\n",
564 entries_map_.occupancy());
565 heap_objects.Sort(comparator);
566 int last_printed_object = -1;
567 bool print_next_object = false;
568 for (int i = 0; i < heap_objects.length(); ++i) {
569 const HeapObjectInfo& object_info = heap_objects[i];
570 if (!object_info.IsValid()) {
571 ++untracked;
572 if (last_printed_object != i - 1) {
573 if (i > 0) {
574 PrintF("%d objects were skipped\n", i - 1 - last_printed_object);
575 heap_objects[i - 1].Print();
576 }
577 }
578 object_info.Print();
579 last_printed_object = i;
580 print_next_object = true;
581 } else if (print_next_object) {
582 object_info.Print();
583 print_next_object = false;
584 last_printed_object = i;
585 }
586 }
587 if (last_printed_object < heap_objects.length() - 1) {
588 PrintF("Last %d objects were skipped\n",
589 heap_objects.length() - 1 - last_printed_object);
590 }
591 PrintF("End HeapObjectsMap::FindUntrackedObjects. %d entries in map.\n\n",
592 entries_map_.occupancy());
593 }
594 return untracked;
595 }
596
597
PushHeapObjectsStats(OutputStream * stream,int64_t * timestamp_us)598 SnapshotObjectId HeapObjectsMap::PushHeapObjectsStats(OutputStream* stream,
599 int64_t* timestamp_us) {
600 UpdateHeapObjectsMap();
601 time_intervals_.Add(TimeInterval(next_id_));
602 int prefered_chunk_size = stream->GetChunkSize();
603 List<v8::HeapStatsUpdate> stats_buffer;
604 DCHECK(!entries_.is_empty());
605 EntryInfo* entry_info = &entries_.first();
606 EntryInfo* end_entry_info = &entries_.last() + 1;
607 for (int time_interval_index = 0;
608 time_interval_index < time_intervals_.length();
609 ++time_interval_index) {
610 TimeInterval& time_interval = time_intervals_[time_interval_index];
611 SnapshotObjectId time_interval_id = time_interval.id;
612 uint32_t entries_size = 0;
613 EntryInfo* start_entry_info = entry_info;
614 while (entry_info < end_entry_info && entry_info->id < time_interval_id) {
615 entries_size += entry_info->size;
616 ++entry_info;
617 }
618 uint32_t entries_count =
619 static_cast<uint32_t>(entry_info - start_entry_info);
620 if (time_interval.count != entries_count ||
621 time_interval.size != entries_size) {
622 stats_buffer.Add(v8::HeapStatsUpdate(
623 time_interval_index,
624 time_interval.count = entries_count,
625 time_interval.size = entries_size));
626 if (stats_buffer.length() >= prefered_chunk_size) {
627 OutputStream::WriteResult result = stream->WriteHeapStatsChunk(
628 &stats_buffer.first(), stats_buffer.length());
629 if (result == OutputStream::kAbort) return last_assigned_id();
630 stats_buffer.Clear();
631 }
632 }
633 }
634 DCHECK(entry_info == end_entry_info);
635 if (!stats_buffer.is_empty()) {
636 OutputStream::WriteResult result = stream->WriteHeapStatsChunk(
637 &stats_buffer.first(), stats_buffer.length());
638 if (result == OutputStream::kAbort) return last_assigned_id();
639 }
640 stream->EndOfStream();
641 if (timestamp_us) {
642 *timestamp_us = (time_intervals_.last().timestamp -
643 time_intervals_[0].timestamp).InMicroseconds();
644 }
645 return last_assigned_id();
646 }
647
648
RemoveDeadEntries()649 void HeapObjectsMap::RemoveDeadEntries() {
650 DCHECK(entries_.length() > 0 &&
651 entries_.at(0).id == 0 &&
652 entries_.at(0).addr == NULL);
653 int first_free_entry = 1;
654 for (int i = 1; i < entries_.length(); ++i) {
655 EntryInfo& entry_info = entries_.at(i);
656 if (entry_info.accessed) {
657 if (first_free_entry != i) {
658 entries_.at(first_free_entry) = entry_info;
659 }
660 entries_.at(first_free_entry).accessed = false;
661 base::HashMap::Entry* entry = entries_map_.Lookup(
662 entry_info.addr, ComputePointerHash(entry_info.addr));
663 DCHECK(entry);
664 entry->value = reinterpret_cast<void*>(first_free_entry);
665 ++first_free_entry;
666 } else {
667 if (entry_info.addr) {
668 entries_map_.Remove(entry_info.addr,
669 ComputePointerHash(entry_info.addr));
670 }
671 }
672 }
673 entries_.Rewind(first_free_entry);
674 DCHECK(static_cast<uint32_t>(entries_.length()) - 1 ==
675 entries_map_.occupancy());
676 }
677
678
GenerateId(v8::RetainedObjectInfo * info)679 SnapshotObjectId HeapObjectsMap::GenerateId(v8::RetainedObjectInfo* info) {
680 SnapshotObjectId id = static_cast<SnapshotObjectId>(info->GetHash());
681 const char* label = info->GetLabel();
682 id ^= StringHasher::HashSequentialString(label,
683 static_cast<int>(strlen(label)),
684 heap_->HashSeed());
685 intptr_t element_count = info->GetElementCount();
686 if (element_count != -1)
687 id ^= ComputeIntegerHash(static_cast<uint32_t>(element_count),
688 v8::internal::kZeroHashSeed);
689 return id << 1;
690 }
691
692
GetUsedMemorySize() const693 size_t HeapObjectsMap::GetUsedMemorySize() const {
694 return sizeof(*this) +
695 sizeof(base::HashMap::Entry) * entries_map_.capacity() +
696 GetMemoryUsedByList(entries_) + GetMemoryUsedByList(time_intervals_);
697 }
698
HeapEntriesMap()699 HeapEntriesMap::HeapEntriesMap() : entries_() {}
700
Map(HeapThing thing)701 int HeapEntriesMap::Map(HeapThing thing) {
702 base::HashMap::Entry* cache_entry = entries_.Lookup(thing, Hash(thing));
703 if (cache_entry == NULL) return HeapEntry::kNoEntry;
704 return static_cast<int>(reinterpret_cast<intptr_t>(cache_entry->value));
705 }
706
707
Pair(HeapThing thing,int entry)708 void HeapEntriesMap::Pair(HeapThing thing, int entry) {
709 base::HashMap::Entry* cache_entry =
710 entries_.LookupOrInsert(thing, Hash(thing));
711 DCHECK(cache_entry->value == NULL);
712 cache_entry->value = reinterpret_cast<void*>(static_cast<intptr_t>(entry));
713 }
714
HeapObjectsSet()715 HeapObjectsSet::HeapObjectsSet() : entries_() {}
716
Clear()717 void HeapObjectsSet::Clear() {
718 entries_.Clear();
719 }
720
721
Contains(Object * obj)722 bool HeapObjectsSet::Contains(Object* obj) {
723 if (!obj->IsHeapObject()) return false;
724 HeapObject* object = HeapObject::cast(obj);
725 return entries_.Lookup(object, HeapEntriesMap::Hash(object)) != NULL;
726 }
727
728
Insert(Object * obj)729 void HeapObjectsSet::Insert(Object* obj) {
730 if (!obj->IsHeapObject()) return;
731 HeapObject* object = HeapObject::cast(obj);
732 entries_.LookupOrInsert(object, HeapEntriesMap::Hash(object));
733 }
734
735
GetTag(Object * obj)736 const char* HeapObjectsSet::GetTag(Object* obj) {
737 HeapObject* object = HeapObject::cast(obj);
738 base::HashMap::Entry* cache_entry =
739 entries_.Lookup(object, HeapEntriesMap::Hash(object));
740 return cache_entry != NULL
741 ? reinterpret_cast<const char*>(cache_entry->value)
742 : NULL;
743 }
744
745
SetTag(Object * obj,const char * tag)746 V8_NOINLINE void HeapObjectsSet::SetTag(Object* obj, const char* tag) {
747 if (!obj->IsHeapObject()) return;
748 HeapObject* object = HeapObject::cast(obj);
749 base::HashMap::Entry* cache_entry =
750 entries_.LookupOrInsert(object, HeapEntriesMap::Hash(object));
751 cache_entry->value = const_cast<char*>(tag);
752 }
753
754
V8HeapExplorer(HeapSnapshot * snapshot,SnapshottingProgressReportingInterface * progress,v8::HeapProfiler::ObjectNameResolver * resolver)755 V8HeapExplorer::V8HeapExplorer(
756 HeapSnapshot* snapshot,
757 SnapshottingProgressReportingInterface* progress,
758 v8::HeapProfiler::ObjectNameResolver* resolver)
759 : heap_(snapshot->profiler()->heap_object_map()->heap()),
760 snapshot_(snapshot),
761 names_(snapshot_->profiler()->names()),
762 heap_object_map_(snapshot_->profiler()->heap_object_map()),
763 progress_(progress),
764 filler_(NULL),
765 global_object_name_resolver_(resolver) {
766 }
767
768
~V8HeapExplorer()769 V8HeapExplorer::~V8HeapExplorer() {
770 }
771
772
AllocateEntry(HeapThing ptr)773 HeapEntry* V8HeapExplorer::AllocateEntry(HeapThing ptr) {
774 return AddEntry(reinterpret_cast<HeapObject*>(ptr));
775 }
776
777
AddEntry(HeapObject * object)778 HeapEntry* V8HeapExplorer::AddEntry(HeapObject* object) {
779 if (object->IsJSFunction()) {
780 JSFunction* func = JSFunction::cast(object);
781 SharedFunctionInfo* shared = func->shared();
782 const char* name = names_->GetName(String::cast(shared->name()));
783 return AddEntry(object, HeapEntry::kClosure, name);
784 } else if (object->IsJSBoundFunction()) {
785 return AddEntry(object, HeapEntry::kClosure, "native_bind");
786 } else if (object->IsJSRegExp()) {
787 JSRegExp* re = JSRegExp::cast(object);
788 return AddEntry(object,
789 HeapEntry::kRegExp,
790 names_->GetName(re->Pattern()));
791 } else if (object->IsJSObject()) {
792 const char* name = names_->GetName(
793 GetConstructorName(JSObject::cast(object)));
794 if (object->IsJSGlobalObject()) {
795 const char* tag = objects_tags_.GetTag(object);
796 if (tag != NULL) {
797 name = names_->GetFormatted("%s / %s", name, tag);
798 }
799 }
800 return AddEntry(object, HeapEntry::kObject, name);
801 } else if (object->IsString()) {
802 String* string = String::cast(object);
803 if (string->IsConsString())
804 return AddEntry(object,
805 HeapEntry::kConsString,
806 "(concatenated string)");
807 if (string->IsSlicedString())
808 return AddEntry(object,
809 HeapEntry::kSlicedString,
810 "(sliced string)");
811 return AddEntry(object,
812 HeapEntry::kString,
813 names_->GetName(String::cast(object)));
814 } else if (object->IsSymbol()) {
815 if (Symbol::cast(object)->is_private())
816 return AddEntry(object, HeapEntry::kHidden, "private symbol");
817 else
818 return AddEntry(object, HeapEntry::kSymbol, "symbol");
819 } else if (object->IsCode()) {
820 return AddEntry(object, HeapEntry::kCode, "");
821 } else if (object->IsSharedFunctionInfo()) {
822 String* name = String::cast(SharedFunctionInfo::cast(object)->name());
823 return AddEntry(object,
824 HeapEntry::kCode,
825 names_->GetName(name));
826 } else if (object->IsScript()) {
827 Object* name = Script::cast(object)->name();
828 return AddEntry(object,
829 HeapEntry::kCode,
830 name->IsString()
831 ? names_->GetName(String::cast(name))
832 : "");
833 } else if (object->IsNativeContext()) {
834 return AddEntry(object, HeapEntry::kHidden, "system / NativeContext");
835 } else if (object->IsContext()) {
836 return AddEntry(object, HeapEntry::kObject, "system / Context");
837 } else if (object->IsFixedArray() || object->IsFixedDoubleArray() ||
838 object->IsByteArray()) {
839 return AddEntry(object, HeapEntry::kArray, "");
840 } else if (object->IsHeapNumber()) {
841 return AddEntry(object, HeapEntry::kHeapNumber, "number");
842 } else if (object->IsSimd128Value()) {
843 return AddEntry(object, HeapEntry::kSimdValue, "simd");
844 }
845 return AddEntry(object, HeapEntry::kHidden, GetSystemEntryName(object));
846 }
847
848
AddEntry(HeapObject * object,HeapEntry::Type type,const char * name)849 HeapEntry* V8HeapExplorer::AddEntry(HeapObject* object,
850 HeapEntry::Type type,
851 const char* name) {
852 return AddEntry(object->address(), type, name, object->Size());
853 }
854
855
AddEntry(Address address,HeapEntry::Type type,const char * name,size_t size)856 HeapEntry* V8HeapExplorer::AddEntry(Address address,
857 HeapEntry::Type type,
858 const char* name,
859 size_t size) {
860 SnapshotObjectId object_id = heap_object_map_->FindOrAddEntry(
861 address, static_cast<unsigned int>(size));
862 unsigned trace_node_id = 0;
863 if (AllocationTracker* allocation_tracker =
864 snapshot_->profiler()->allocation_tracker()) {
865 trace_node_id =
866 allocation_tracker->address_to_trace()->GetTraceNodeId(address);
867 }
868 return snapshot_->AddEntry(type, name, object_id, size, trace_node_id);
869 }
870
871
872 class SnapshotFiller {
873 public:
SnapshotFiller(HeapSnapshot * snapshot,HeapEntriesMap * entries)874 explicit SnapshotFiller(HeapSnapshot* snapshot, HeapEntriesMap* entries)
875 : snapshot_(snapshot),
876 names_(snapshot->profiler()->names()),
877 entries_(entries) { }
AddEntry(HeapThing ptr,HeapEntriesAllocator * allocator)878 HeapEntry* AddEntry(HeapThing ptr, HeapEntriesAllocator* allocator) {
879 HeapEntry* entry = allocator->AllocateEntry(ptr);
880 entries_->Pair(ptr, entry->index());
881 return entry;
882 }
FindEntry(HeapThing ptr)883 HeapEntry* FindEntry(HeapThing ptr) {
884 int index = entries_->Map(ptr);
885 return index != HeapEntry::kNoEntry ? &snapshot_->entries()[index] : NULL;
886 }
FindOrAddEntry(HeapThing ptr,HeapEntriesAllocator * allocator)887 HeapEntry* FindOrAddEntry(HeapThing ptr, HeapEntriesAllocator* allocator) {
888 HeapEntry* entry = FindEntry(ptr);
889 return entry != NULL ? entry : AddEntry(ptr, allocator);
890 }
SetIndexedReference(HeapGraphEdge::Type type,int parent,int index,HeapEntry * child_entry)891 void SetIndexedReference(HeapGraphEdge::Type type,
892 int parent,
893 int index,
894 HeapEntry* child_entry) {
895 HeapEntry* parent_entry = &snapshot_->entries()[parent];
896 parent_entry->SetIndexedReference(type, index, child_entry);
897 }
SetIndexedAutoIndexReference(HeapGraphEdge::Type type,int parent,HeapEntry * child_entry)898 void SetIndexedAutoIndexReference(HeapGraphEdge::Type type,
899 int parent,
900 HeapEntry* child_entry) {
901 HeapEntry* parent_entry = &snapshot_->entries()[parent];
902 int index = parent_entry->children_count() + 1;
903 parent_entry->SetIndexedReference(type, index, child_entry);
904 }
SetNamedReference(HeapGraphEdge::Type type,int parent,const char * reference_name,HeapEntry * child_entry)905 void SetNamedReference(HeapGraphEdge::Type type,
906 int parent,
907 const char* reference_name,
908 HeapEntry* child_entry) {
909 HeapEntry* parent_entry = &snapshot_->entries()[parent];
910 parent_entry->SetNamedReference(type, reference_name, child_entry);
911 }
SetNamedAutoIndexReference(HeapGraphEdge::Type type,int parent,HeapEntry * child_entry)912 void SetNamedAutoIndexReference(HeapGraphEdge::Type type,
913 int parent,
914 HeapEntry* child_entry) {
915 HeapEntry* parent_entry = &snapshot_->entries()[parent];
916 int index = parent_entry->children_count() + 1;
917 parent_entry->SetNamedReference(
918 type,
919 names_->GetName(index),
920 child_entry);
921 }
922
923 private:
924 HeapSnapshot* snapshot_;
925 StringsStorage* names_;
926 HeapEntriesMap* entries_;
927 };
928
929
GetSystemEntryName(HeapObject * object)930 const char* V8HeapExplorer::GetSystemEntryName(HeapObject* object) {
931 switch (object->map()->instance_type()) {
932 case MAP_TYPE:
933 switch (Map::cast(object)->instance_type()) {
934 #define MAKE_STRING_MAP_CASE(instance_type, size, name, Name) \
935 case instance_type: return "system / Map (" #Name ")";
936 STRING_TYPE_LIST(MAKE_STRING_MAP_CASE)
937 #undef MAKE_STRING_MAP_CASE
938 default: return "system / Map";
939 }
940 case CELL_TYPE: return "system / Cell";
941 case PROPERTY_CELL_TYPE: return "system / PropertyCell";
942 case FOREIGN_TYPE: return "system / Foreign";
943 case ODDBALL_TYPE: return "system / Oddball";
944 #define MAKE_STRUCT_CASE(NAME, Name, name) \
945 case NAME##_TYPE: return "system / "#Name;
946 STRUCT_LIST(MAKE_STRUCT_CASE)
947 #undef MAKE_STRUCT_CASE
948 default: return "system";
949 }
950 }
951
952
EstimateObjectsCount(HeapIterator * iterator)953 int V8HeapExplorer::EstimateObjectsCount(HeapIterator* iterator) {
954 int objects_count = 0;
955 for (HeapObject* obj = iterator->next();
956 obj != NULL;
957 obj = iterator->next()) {
958 objects_count++;
959 }
960 return objects_count;
961 }
962
963
964 class IndexedReferencesExtractor : public ObjectVisitor {
965 public:
IndexedReferencesExtractor(V8HeapExplorer * generator,HeapObject * parent_obj,int parent)966 IndexedReferencesExtractor(V8HeapExplorer* generator, HeapObject* parent_obj,
967 int parent)
968 : generator_(generator),
969 parent_obj_(parent_obj),
970 parent_start_(HeapObject::RawField(parent_obj_, 0)),
971 parent_end_(HeapObject::RawField(parent_obj_, parent_obj_->Size())),
972 parent_(parent),
973 next_index_(0) {}
VisitCodeEntry(Address entry_address)974 void VisitCodeEntry(Address entry_address) override {
975 Code* code = Code::cast(Code::GetObjectFromEntryAddress(entry_address));
976 generator_->SetInternalReference(parent_obj_, parent_, "code", code);
977 generator_->TagCodeObject(code);
978 }
VisitPointers(Object ** start,Object ** end)979 void VisitPointers(Object** start, Object** end) override {
980 for (Object** p = start; p < end; p++) {
981 int index = static_cast<int>(p - HeapObject::RawField(parent_obj_, 0));
982 ++next_index_;
983 // |p| could be outside of the object, e.g., while visiting RelocInfo of
984 // code objects.
985 if (p >= parent_start_ && p < parent_end_ && generator_->marks_[index]) {
986 generator_->marks_[index] = false;
987 continue;
988 }
989 generator_->SetHiddenReference(parent_obj_, parent_, next_index_, *p,
990 index * kPointerSize);
991 }
992 }
993
994 private:
995 V8HeapExplorer* generator_;
996 HeapObject* parent_obj_;
997 Object** parent_start_;
998 Object** parent_end_;
999 int parent_;
1000 int next_index_;
1001 };
1002
1003
ExtractReferencesPass1(int entry,HeapObject * obj)1004 bool V8HeapExplorer::ExtractReferencesPass1(int entry, HeapObject* obj) {
1005 if (obj->IsFixedArray()) return false; // FixedArrays are processed on pass 2
1006
1007 if (obj->IsJSGlobalProxy()) {
1008 ExtractJSGlobalProxyReferences(entry, JSGlobalProxy::cast(obj));
1009 } else if (obj->IsJSArrayBuffer()) {
1010 ExtractJSArrayBufferReferences(entry, JSArrayBuffer::cast(obj));
1011 } else if (obj->IsJSObject()) {
1012 if (obj->IsJSWeakSet()) {
1013 ExtractJSWeakCollectionReferences(entry, JSWeakSet::cast(obj));
1014 } else if (obj->IsJSWeakMap()) {
1015 ExtractJSWeakCollectionReferences(entry, JSWeakMap::cast(obj));
1016 } else if (obj->IsJSSet()) {
1017 ExtractJSCollectionReferences(entry, JSSet::cast(obj));
1018 } else if (obj->IsJSMap()) {
1019 ExtractJSCollectionReferences(entry, JSMap::cast(obj));
1020 }
1021 ExtractJSObjectReferences(entry, JSObject::cast(obj));
1022 } else if (obj->IsString()) {
1023 ExtractStringReferences(entry, String::cast(obj));
1024 } else if (obj->IsSymbol()) {
1025 ExtractSymbolReferences(entry, Symbol::cast(obj));
1026 } else if (obj->IsMap()) {
1027 ExtractMapReferences(entry, Map::cast(obj));
1028 } else if (obj->IsSharedFunctionInfo()) {
1029 ExtractSharedFunctionInfoReferences(entry, SharedFunctionInfo::cast(obj));
1030 } else if (obj->IsScript()) {
1031 ExtractScriptReferences(entry, Script::cast(obj));
1032 } else if (obj->IsAccessorInfo()) {
1033 ExtractAccessorInfoReferences(entry, AccessorInfo::cast(obj));
1034 } else if (obj->IsAccessorPair()) {
1035 ExtractAccessorPairReferences(entry, AccessorPair::cast(obj));
1036 } else if (obj->IsCode()) {
1037 ExtractCodeReferences(entry, Code::cast(obj));
1038 } else if (obj->IsBox()) {
1039 ExtractBoxReferences(entry, Box::cast(obj));
1040 } else if (obj->IsCell()) {
1041 ExtractCellReferences(entry, Cell::cast(obj));
1042 } else if (obj->IsWeakCell()) {
1043 ExtractWeakCellReferences(entry, WeakCell::cast(obj));
1044 } else if (obj->IsPropertyCell()) {
1045 ExtractPropertyCellReferences(entry, PropertyCell::cast(obj));
1046 } else if (obj->IsAllocationSite()) {
1047 ExtractAllocationSiteReferences(entry, AllocationSite::cast(obj));
1048 }
1049 return true;
1050 }
1051
1052
ExtractReferencesPass2(int entry,HeapObject * obj)1053 bool V8HeapExplorer::ExtractReferencesPass2(int entry, HeapObject* obj) {
1054 if (!obj->IsFixedArray()) return false;
1055
1056 if (obj->IsContext()) {
1057 ExtractContextReferences(entry, Context::cast(obj));
1058 } else {
1059 ExtractFixedArrayReferences(entry, FixedArray::cast(obj));
1060 }
1061 return true;
1062 }
1063
1064
ExtractJSGlobalProxyReferences(int entry,JSGlobalProxy * proxy)1065 void V8HeapExplorer::ExtractJSGlobalProxyReferences(
1066 int entry, JSGlobalProxy* proxy) {
1067 SetInternalReference(proxy, entry,
1068 "native_context", proxy->native_context(),
1069 JSGlobalProxy::kNativeContextOffset);
1070 }
1071
1072
ExtractJSObjectReferences(int entry,JSObject * js_obj)1073 void V8HeapExplorer::ExtractJSObjectReferences(
1074 int entry, JSObject* js_obj) {
1075 HeapObject* obj = js_obj;
1076 ExtractPropertyReferences(js_obj, entry);
1077 ExtractElementReferences(js_obj, entry);
1078 ExtractInternalReferences(js_obj, entry);
1079 PrototypeIterator iter(heap_->isolate(), js_obj);
1080 SetPropertyReference(obj, entry, heap_->proto_string(), iter.GetCurrent());
1081 if (obj->IsJSBoundFunction()) {
1082 JSBoundFunction* js_fun = JSBoundFunction::cast(obj);
1083 TagObject(js_fun->bound_arguments(), "(bound arguments)");
1084 SetInternalReference(js_fun, entry, "bindings", js_fun->bound_arguments(),
1085 JSBoundFunction::kBoundArgumentsOffset);
1086 SetInternalReference(js_obj, entry, "bound_this", js_fun->bound_this(),
1087 JSBoundFunction::kBoundThisOffset);
1088 SetInternalReference(js_obj, entry, "bound_function",
1089 js_fun->bound_target_function(),
1090 JSBoundFunction::kBoundTargetFunctionOffset);
1091 FixedArray* bindings = js_fun->bound_arguments();
1092 for (int i = 0; i < bindings->length(); i++) {
1093 const char* reference_name = names_->GetFormatted("bound_argument_%d", i);
1094 SetNativeBindReference(js_obj, entry, reference_name, bindings->get(i));
1095 }
1096 } else if (obj->IsJSFunction()) {
1097 JSFunction* js_fun = JSFunction::cast(js_obj);
1098 Object* proto_or_map = js_fun->prototype_or_initial_map();
1099 if (!proto_or_map->IsTheHole(heap_->isolate())) {
1100 if (!proto_or_map->IsMap()) {
1101 SetPropertyReference(
1102 obj, entry,
1103 heap_->prototype_string(), proto_or_map,
1104 NULL,
1105 JSFunction::kPrototypeOrInitialMapOffset);
1106 } else {
1107 SetPropertyReference(
1108 obj, entry,
1109 heap_->prototype_string(), js_fun->prototype());
1110 SetInternalReference(
1111 obj, entry, "initial_map", proto_or_map,
1112 JSFunction::kPrototypeOrInitialMapOffset);
1113 }
1114 }
1115 SharedFunctionInfo* shared_info = js_fun->shared();
1116 TagObject(js_fun->literals(), "(function literals)");
1117 SetInternalReference(js_fun, entry, "literals", js_fun->literals(),
1118 JSFunction::kLiteralsOffset);
1119 TagObject(shared_info, "(shared function info)");
1120 SetInternalReference(js_fun, entry,
1121 "shared", shared_info,
1122 JSFunction::kSharedFunctionInfoOffset);
1123 TagObject(js_fun->context(), "(context)");
1124 SetInternalReference(js_fun, entry,
1125 "context", js_fun->context(),
1126 JSFunction::kContextOffset);
1127 // Ensure no new weak references appeared in JSFunction.
1128 STATIC_ASSERT(JSFunction::kCodeEntryOffset ==
1129 JSFunction::kNonWeakFieldsEndOffset);
1130 STATIC_ASSERT(JSFunction::kCodeEntryOffset + kPointerSize ==
1131 JSFunction::kNextFunctionLinkOffset);
1132 STATIC_ASSERT(JSFunction::kNextFunctionLinkOffset + kPointerSize
1133 == JSFunction::kSize);
1134 } else if (obj->IsJSGlobalObject()) {
1135 JSGlobalObject* global_obj = JSGlobalObject::cast(obj);
1136 SetInternalReference(global_obj, entry, "native_context",
1137 global_obj->native_context(),
1138 JSGlobalObject::kNativeContextOffset);
1139 SetInternalReference(global_obj, entry, "global_proxy",
1140 global_obj->global_proxy(),
1141 JSGlobalObject::kGlobalProxyOffset);
1142 STATIC_ASSERT(JSGlobalObject::kSize - JSObject::kHeaderSize ==
1143 2 * kPointerSize);
1144 } else if (obj->IsJSArrayBufferView()) {
1145 JSArrayBufferView* view = JSArrayBufferView::cast(obj);
1146 SetInternalReference(view, entry, "buffer", view->buffer(),
1147 JSArrayBufferView::kBufferOffset);
1148 }
1149 TagObject(js_obj->properties(), "(object properties)");
1150 SetInternalReference(obj, entry,
1151 "properties", js_obj->properties(),
1152 JSObject::kPropertiesOffset);
1153 TagObject(js_obj->elements(), "(object elements)");
1154 SetInternalReference(obj, entry,
1155 "elements", js_obj->elements(),
1156 JSObject::kElementsOffset);
1157 }
1158
1159
ExtractStringReferences(int entry,String * string)1160 void V8HeapExplorer::ExtractStringReferences(int entry, String* string) {
1161 if (string->IsConsString()) {
1162 ConsString* cs = ConsString::cast(string);
1163 SetInternalReference(cs, entry, "first", cs->first(),
1164 ConsString::kFirstOffset);
1165 SetInternalReference(cs, entry, "second", cs->second(),
1166 ConsString::kSecondOffset);
1167 } else if (string->IsSlicedString()) {
1168 SlicedString* ss = SlicedString::cast(string);
1169 SetInternalReference(ss, entry, "parent", ss->parent(),
1170 SlicedString::kParentOffset);
1171 }
1172 }
1173
1174
ExtractSymbolReferences(int entry,Symbol * symbol)1175 void V8HeapExplorer::ExtractSymbolReferences(int entry, Symbol* symbol) {
1176 SetInternalReference(symbol, entry,
1177 "name", symbol->name(),
1178 Symbol::kNameOffset);
1179 }
1180
1181
ExtractJSCollectionReferences(int entry,JSCollection * collection)1182 void V8HeapExplorer::ExtractJSCollectionReferences(int entry,
1183 JSCollection* collection) {
1184 SetInternalReference(collection, entry, "table", collection->table(),
1185 JSCollection::kTableOffset);
1186 }
1187
ExtractJSWeakCollectionReferences(int entry,JSWeakCollection * obj)1188 void V8HeapExplorer::ExtractJSWeakCollectionReferences(int entry,
1189 JSWeakCollection* obj) {
1190 if (obj->table()->IsHashTable()) {
1191 ObjectHashTable* table = ObjectHashTable::cast(obj->table());
1192 TagFixedArraySubType(table, JS_WEAK_COLLECTION_SUB_TYPE);
1193 }
1194 SetInternalReference(obj, entry, "table", obj->table(),
1195 JSWeakCollection::kTableOffset);
1196 }
1197
ExtractContextReferences(int entry,Context * context)1198 void V8HeapExplorer::ExtractContextReferences(int entry, Context* context) {
1199 if (context == context->declaration_context()) {
1200 ScopeInfo* scope_info = context->closure()->shared()->scope_info();
1201 // Add context allocated locals.
1202 int context_locals = scope_info->ContextLocalCount();
1203 for (int i = 0; i < context_locals; ++i) {
1204 String* local_name = scope_info->ContextLocalName(i);
1205 int idx = Context::MIN_CONTEXT_SLOTS + i;
1206 SetContextReference(context, entry, local_name, context->get(idx),
1207 Context::OffsetOfElementAt(idx));
1208 }
1209 if (scope_info->HasFunctionName()) {
1210 String* name = scope_info->FunctionName();
1211 int idx = scope_info->FunctionContextSlotIndex(name);
1212 if (idx >= 0) {
1213 SetContextReference(context, entry, name, context->get(idx),
1214 Context::OffsetOfElementAt(idx));
1215 }
1216 }
1217 }
1218
1219 #define EXTRACT_CONTEXT_FIELD(index, type, name) \
1220 if (Context::index < Context::FIRST_WEAK_SLOT || \
1221 Context::index == Context::MAP_CACHE_INDEX) { \
1222 SetInternalReference(context, entry, #name, context->get(Context::index), \
1223 FixedArray::OffsetOfElementAt(Context::index)); \
1224 } else { \
1225 SetWeakReference(context, entry, #name, context->get(Context::index), \
1226 FixedArray::OffsetOfElementAt(Context::index)); \
1227 }
1228 EXTRACT_CONTEXT_FIELD(CLOSURE_INDEX, JSFunction, closure);
1229 EXTRACT_CONTEXT_FIELD(PREVIOUS_INDEX, Context, previous);
1230 EXTRACT_CONTEXT_FIELD(EXTENSION_INDEX, HeapObject, extension);
1231 EXTRACT_CONTEXT_FIELD(NATIVE_CONTEXT_INDEX, Context, native_context);
1232 if (context->IsNativeContext()) {
1233 TagObject(context->normalized_map_cache(), "(context norm. map cache)");
1234 TagObject(context->embedder_data(), "(context data)");
1235 NATIVE_CONTEXT_FIELDS(EXTRACT_CONTEXT_FIELD)
1236 EXTRACT_CONTEXT_FIELD(OPTIMIZED_FUNCTIONS_LIST, unused,
1237 optimized_functions_list);
1238 EXTRACT_CONTEXT_FIELD(OPTIMIZED_CODE_LIST, unused, optimized_code_list);
1239 EXTRACT_CONTEXT_FIELD(DEOPTIMIZED_CODE_LIST, unused, deoptimized_code_list);
1240 #undef EXTRACT_CONTEXT_FIELD
1241 STATIC_ASSERT(Context::OPTIMIZED_FUNCTIONS_LIST ==
1242 Context::FIRST_WEAK_SLOT);
1243 STATIC_ASSERT(Context::NEXT_CONTEXT_LINK + 1 ==
1244 Context::NATIVE_CONTEXT_SLOTS);
1245 STATIC_ASSERT(Context::FIRST_WEAK_SLOT + 4 ==
1246 Context::NATIVE_CONTEXT_SLOTS);
1247 }
1248 }
1249
1250
ExtractMapReferences(int entry,Map * map)1251 void V8HeapExplorer::ExtractMapReferences(int entry, Map* map) {
1252 Object* raw_transitions_or_prototype_info = map->raw_transitions();
1253 if (TransitionArray::IsFullTransitionArray(
1254 raw_transitions_or_prototype_info)) {
1255 TransitionArray* transitions =
1256 TransitionArray::cast(raw_transitions_or_prototype_info);
1257 if (map->CanTransition() && transitions->HasPrototypeTransitions()) {
1258 TagObject(transitions->GetPrototypeTransitions(),
1259 "(prototype transitions)");
1260 }
1261
1262 TagObject(transitions, "(transition array)");
1263 SetInternalReference(map, entry, "transitions", transitions,
1264 Map::kTransitionsOrPrototypeInfoOffset);
1265 } else if (TransitionArray::IsSimpleTransition(
1266 raw_transitions_or_prototype_info)) {
1267 TagObject(raw_transitions_or_prototype_info, "(transition)");
1268 SetInternalReference(map, entry, "transition",
1269 raw_transitions_or_prototype_info,
1270 Map::kTransitionsOrPrototypeInfoOffset);
1271 } else if (map->is_prototype_map()) {
1272 TagObject(raw_transitions_or_prototype_info, "prototype_info");
1273 SetInternalReference(map, entry, "prototype_info",
1274 raw_transitions_or_prototype_info,
1275 Map::kTransitionsOrPrototypeInfoOffset);
1276 }
1277 DescriptorArray* descriptors = map->instance_descriptors();
1278 TagObject(descriptors, "(map descriptors)");
1279 SetInternalReference(map, entry, "descriptors", descriptors,
1280 Map::kDescriptorsOffset);
1281 SetInternalReference(map, entry, "code_cache", map->code_cache(),
1282 Map::kCodeCacheOffset);
1283 SetInternalReference(map, entry, "prototype", map->prototype(),
1284 Map::kPrototypeOffset);
1285 #if V8_DOUBLE_FIELDS_UNBOXING
1286 if (FLAG_unbox_double_fields) {
1287 SetInternalReference(map, entry, "layout_descriptor",
1288 map->layout_descriptor(),
1289 Map::kLayoutDescriptorOffset);
1290 }
1291 #endif
1292 Object* constructor_or_backpointer = map->constructor_or_backpointer();
1293 if (constructor_or_backpointer->IsMap()) {
1294 TagObject(constructor_or_backpointer, "(back pointer)");
1295 SetInternalReference(map, entry, "back_pointer", constructor_or_backpointer,
1296 Map::kConstructorOrBackPointerOffset);
1297 } else {
1298 SetInternalReference(map, entry, "constructor", constructor_or_backpointer,
1299 Map::kConstructorOrBackPointerOffset);
1300 }
1301 TagObject(map->dependent_code(), "(dependent code)");
1302 SetInternalReference(map, entry, "dependent_code", map->dependent_code(),
1303 Map::kDependentCodeOffset);
1304 TagObject(map->weak_cell_cache(), "(weak cell)");
1305 SetInternalReference(map, entry, "weak_cell_cache", map->weak_cell_cache(),
1306 Map::kWeakCellCacheOffset);
1307 }
1308
1309
ExtractSharedFunctionInfoReferences(int entry,SharedFunctionInfo * shared)1310 void V8HeapExplorer::ExtractSharedFunctionInfoReferences(
1311 int entry, SharedFunctionInfo* shared) {
1312 HeapObject* obj = shared;
1313 String* shared_name = shared->DebugName();
1314 const char* name = NULL;
1315 if (shared_name != heap_->empty_string()) {
1316 name = names_->GetName(shared_name);
1317 TagObject(shared->code(), names_->GetFormatted("(code for %s)", name));
1318 } else {
1319 TagObject(shared->code(), names_->GetFormatted("(%s code)",
1320 Code::Kind2String(shared->code()->kind())));
1321 }
1322
1323 SetInternalReference(obj, entry,
1324 "name", shared->name(),
1325 SharedFunctionInfo::kNameOffset);
1326 SetInternalReference(obj, entry,
1327 "code", shared->code(),
1328 SharedFunctionInfo::kCodeOffset);
1329 TagObject(shared->scope_info(), "(function scope info)");
1330 SetInternalReference(obj, entry,
1331 "scope_info", shared->scope_info(),
1332 SharedFunctionInfo::kScopeInfoOffset);
1333 SetInternalReference(obj, entry,
1334 "instance_class_name", shared->instance_class_name(),
1335 SharedFunctionInfo::kInstanceClassNameOffset);
1336 SetInternalReference(obj, entry,
1337 "script", shared->script(),
1338 SharedFunctionInfo::kScriptOffset);
1339 const char* construct_stub_name = name ?
1340 names_->GetFormatted("(construct stub code for %s)", name) :
1341 "(construct stub code)";
1342 TagObject(shared->construct_stub(), construct_stub_name);
1343 SetInternalReference(obj, entry,
1344 "construct_stub", shared->construct_stub(),
1345 SharedFunctionInfo::kConstructStubOffset);
1346 SetInternalReference(obj, entry,
1347 "function_data", shared->function_data(),
1348 SharedFunctionInfo::kFunctionDataOffset);
1349 SetInternalReference(obj, entry,
1350 "debug_info", shared->debug_info(),
1351 SharedFunctionInfo::kDebugInfoOffset);
1352 SetInternalReference(obj, entry, "function_identifier",
1353 shared->function_identifier(),
1354 SharedFunctionInfo::kFunctionIdentifierOffset);
1355 SetInternalReference(obj, entry,
1356 "optimized_code_map", shared->optimized_code_map(),
1357 SharedFunctionInfo::kOptimizedCodeMapOffset);
1358 SetInternalReference(obj, entry, "feedback_metadata",
1359 shared->feedback_metadata(),
1360 SharedFunctionInfo::kFeedbackMetadataOffset);
1361 }
1362
1363
ExtractScriptReferences(int entry,Script * script)1364 void V8HeapExplorer::ExtractScriptReferences(int entry, Script* script) {
1365 HeapObject* obj = script;
1366 SetInternalReference(obj, entry,
1367 "source", script->source(),
1368 Script::kSourceOffset);
1369 SetInternalReference(obj, entry,
1370 "name", script->name(),
1371 Script::kNameOffset);
1372 SetInternalReference(obj, entry,
1373 "context_data", script->context_data(),
1374 Script::kContextOffset);
1375 TagObject(script->line_ends(), "(script line ends)");
1376 SetInternalReference(obj, entry,
1377 "line_ends", script->line_ends(),
1378 Script::kLineEndsOffset);
1379 }
1380
1381
ExtractAccessorInfoReferences(int entry,AccessorInfo * accessor_info)1382 void V8HeapExplorer::ExtractAccessorInfoReferences(
1383 int entry, AccessorInfo* accessor_info) {
1384 SetInternalReference(accessor_info, entry, "name", accessor_info->name(),
1385 AccessorInfo::kNameOffset);
1386 SetInternalReference(accessor_info, entry, "expected_receiver_type",
1387 accessor_info->expected_receiver_type(),
1388 AccessorInfo::kExpectedReceiverTypeOffset);
1389 if (accessor_info->IsAccessorInfo()) {
1390 AccessorInfo* executable_accessor_info = AccessorInfo::cast(accessor_info);
1391 SetInternalReference(executable_accessor_info, entry, "getter",
1392 executable_accessor_info->getter(),
1393 AccessorInfo::kGetterOffset);
1394 SetInternalReference(executable_accessor_info, entry, "setter",
1395 executable_accessor_info->setter(),
1396 AccessorInfo::kSetterOffset);
1397 SetInternalReference(executable_accessor_info, entry, "data",
1398 executable_accessor_info->data(),
1399 AccessorInfo::kDataOffset);
1400 }
1401 }
1402
1403
ExtractAccessorPairReferences(int entry,AccessorPair * accessors)1404 void V8HeapExplorer::ExtractAccessorPairReferences(
1405 int entry, AccessorPair* accessors) {
1406 SetInternalReference(accessors, entry, "getter", accessors->getter(),
1407 AccessorPair::kGetterOffset);
1408 SetInternalReference(accessors, entry, "setter", accessors->setter(),
1409 AccessorPair::kSetterOffset);
1410 }
1411
1412
TagBuiltinCodeObject(Code * code,const char * name)1413 void V8HeapExplorer::TagBuiltinCodeObject(Code* code, const char* name) {
1414 TagObject(code, names_->GetFormatted("(%s builtin)", name));
1415 }
1416
1417
TagCodeObject(Code * code)1418 void V8HeapExplorer::TagCodeObject(Code* code) {
1419 if (code->kind() == Code::STUB) {
1420 TagObject(code, names_->GetFormatted(
1421 "(%s code)",
1422 CodeStub::MajorName(CodeStub::GetMajorKey(code))));
1423 }
1424 }
1425
1426
ExtractCodeReferences(int entry,Code * code)1427 void V8HeapExplorer::ExtractCodeReferences(int entry, Code* code) {
1428 TagCodeObject(code);
1429 TagObject(code->relocation_info(), "(code relocation info)");
1430 SetInternalReference(code, entry,
1431 "relocation_info", code->relocation_info(),
1432 Code::kRelocationInfoOffset);
1433 SetInternalReference(code, entry,
1434 "handler_table", code->handler_table(),
1435 Code::kHandlerTableOffset);
1436 TagObject(code->deoptimization_data(), "(code deopt data)");
1437 SetInternalReference(code, entry,
1438 "deoptimization_data", code->deoptimization_data(),
1439 Code::kDeoptimizationDataOffset);
1440 TagObject(code->source_position_table(), "(source position table)");
1441 SetInternalReference(code, entry, "source_position_table",
1442 code->source_position_table(),
1443 Code::kSourcePositionTableOffset);
1444 if (code->kind() == Code::FUNCTION) {
1445 SetInternalReference(code, entry, "type_feedback_info",
1446 code->type_feedback_info(),
1447 Code::kTypeFeedbackInfoOffset);
1448 }
1449 SetInternalReference(code, entry, "gc_metadata", code->gc_metadata(),
1450 Code::kGCMetadataOffset);
1451 }
1452
ExtractBoxReferences(int entry,Box * box)1453 void V8HeapExplorer::ExtractBoxReferences(int entry, Box* box) {
1454 SetInternalReference(box, entry, "value", box->value(), Box::kValueOffset);
1455 }
1456
ExtractCellReferences(int entry,Cell * cell)1457 void V8HeapExplorer::ExtractCellReferences(int entry, Cell* cell) {
1458 SetInternalReference(cell, entry, "value", cell->value(), Cell::kValueOffset);
1459 }
1460
ExtractWeakCellReferences(int entry,WeakCell * weak_cell)1461 void V8HeapExplorer::ExtractWeakCellReferences(int entry, WeakCell* weak_cell) {
1462 TagObject(weak_cell, "(weak cell)");
1463 SetWeakReference(weak_cell, entry, "value", weak_cell->value(),
1464 WeakCell::kValueOffset);
1465 }
1466
ExtractPropertyCellReferences(int entry,PropertyCell * cell)1467 void V8HeapExplorer::ExtractPropertyCellReferences(int entry,
1468 PropertyCell* cell) {
1469 SetInternalReference(cell, entry, "value", cell->value(),
1470 PropertyCell::kValueOffset);
1471 TagObject(cell->dependent_code(), "(dependent code)");
1472 SetInternalReference(cell, entry, "dependent_code", cell->dependent_code(),
1473 PropertyCell::kDependentCodeOffset);
1474 }
1475
1476
ExtractAllocationSiteReferences(int entry,AllocationSite * site)1477 void V8HeapExplorer::ExtractAllocationSiteReferences(int entry,
1478 AllocationSite* site) {
1479 SetInternalReference(site, entry, "transition_info", site->transition_info(),
1480 AllocationSite::kTransitionInfoOffset);
1481 SetInternalReference(site, entry, "nested_site", site->nested_site(),
1482 AllocationSite::kNestedSiteOffset);
1483 TagObject(site->dependent_code(), "(dependent code)");
1484 SetInternalReference(site, entry, "dependent_code", site->dependent_code(),
1485 AllocationSite::kDependentCodeOffset);
1486 // Do not visit weak_next as it is not visited by the StaticVisitor,
1487 // and we're not very interested in weak_next field here.
1488 STATIC_ASSERT(AllocationSite::kWeakNextOffset >=
1489 AllocationSite::kPointerFieldsEndOffset);
1490 }
1491
1492
1493 class JSArrayBufferDataEntryAllocator : public HeapEntriesAllocator {
1494 public:
JSArrayBufferDataEntryAllocator(size_t size,V8HeapExplorer * explorer)1495 JSArrayBufferDataEntryAllocator(size_t size, V8HeapExplorer* explorer)
1496 : size_(size)
1497 , explorer_(explorer) {
1498 }
AllocateEntry(HeapThing ptr)1499 virtual HeapEntry* AllocateEntry(HeapThing ptr) {
1500 return explorer_->AddEntry(
1501 static_cast<Address>(ptr),
1502 HeapEntry::kNative, "system / JSArrayBufferData", size_);
1503 }
1504 private:
1505 size_t size_;
1506 V8HeapExplorer* explorer_;
1507 };
1508
1509
ExtractJSArrayBufferReferences(int entry,JSArrayBuffer * buffer)1510 void V8HeapExplorer::ExtractJSArrayBufferReferences(
1511 int entry, JSArrayBuffer* buffer) {
1512 // Setup a reference to a native memory backing_store object.
1513 if (!buffer->backing_store())
1514 return;
1515 size_t data_size = NumberToSize(buffer->byte_length());
1516 JSArrayBufferDataEntryAllocator allocator(data_size, this);
1517 HeapEntry* data_entry =
1518 filler_->FindOrAddEntry(buffer->backing_store(), &allocator);
1519 filler_->SetNamedReference(HeapGraphEdge::kInternal,
1520 entry, "backing_store", data_entry);
1521 }
1522
ExtractFixedArrayReferences(int entry,FixedArray * array)1523 void V8HeapExplorer::ExtractFixedArrayReferences(int entry, FixedArray* array) {
1524 auto it = array_types_.find(array);
1525 if (it == array_types_.end()) {
1526 for (int i = 0, l = array->length(); i < l; ++i) {
1527 SetInternalReference(array, entry, i, array->get(i),
1528 array->OffsetOfElementAt(i));
1529 }
1530 return;
1531 }
1532 switch (it->second) {
1533 case JS_WEAK_COLLECTION_SUB_TYPE:
1534 for (int i = 0, l = array->length(); i < l; ++i) {
1535 SetWeakReference(array, entry, i, array->get(i),
1536 array->OffsetOfElementAt(i));
1537 }
1538 break;
1539
1540 // TODO(alph): Add special processing for other types of FixedArrays.
1541
1542 default:
1543 for (int i = 0, l = array->length(); i < l; ++i) {
1544 SetInternalReference(array, entry, i, array->get(i),
1545 array->OffsetOfElementAt(i));
1546 }
1547 break;
1548 }
1549 }
1550
ExtractPropertyReferences(JSObject * js_obj,int entry)1551 void V8HeapExplorer::ExtractPropertyReferences(JSObject* js_obj, int entry) {
1552 Isolate* isolate = js_obj->GetIsolate();
1553 if (js_obj->HasFastProperties()) {
1554 DescriptorArray* descs = js_obj->map()->instance_descriptors();
1555 int real_size = js_obj->map()->NumberOfOwnDescriptors();
1556 for (int i = 0; i < real_size; i++) {
1557 PropertyDetails details = descs->GetDetails(i);
1558 switch (details.location()) {
1559 case kField: {
1560 Representation r = details.representation();
1561 if (r.IsSmi() || r.IsDouble()) break;
1562
1563 Name* k = descs->GetKey(i);
1564 FieldIndex field_index = FieldIndex::ForDescriptor(js_obj->map(), i);
1565 Object* value = js_obj->RawFastPropertyAt(field_index);
1566 int field_offset =
1567 field_index.is_inobject() ? field_index.offset() : -1;
1568
1569 SetDataOrAccessorPropertyReference(details.kind(), js_obj, entry, k,
1570 value, NULL, field_offset);
1571 break;
1572 }
1573 case kDescriptor:
1574 SetDataOrAccessorPropertyReference(details.kind(), js_obj, entry,
1575 descs->GetKey(i),
1576 descs->GetValue(i));
1577 break;
1578 }
1579 }
1580 } else if (js_obj->IsJSGlobalObject()) {
1581 // We assume that global objects can only have slow properties.
1582 GlobalDictionary* dictionary = js_obj->global_dictionary();
1583 int length = dictionary->Capacity();
1584 for (int i = 0; i < length; ++i) {
1585 Object* k = dictionary->KeyAt(i);
1586 if (dictionary->IsKey(isolate, k)) {
1587 DCHECK(dictionary->ValueAt(i)->IsPropertyCell());
1588 PropertyCell* cell = PropertyCell::cast(dictionary->ValueAt(i));
1589 Object* value = cell->value();
1590 PropertyDetails details = cell->property_details();
1591 SetDataOrAccessorPropertyReference(details.kind(), js_obj, entry,
1592 Name::cast(k), value);
1593 }
1594 }
1595 } else {
1596 NameDictionary* dictionary = js_obj->property_dictionary();
1597 int length = dictionary->Capacity();
1598 for (int i = 0; i < length; ++i) {
1599 Object* k = dictionary->KeyAt(i);
1600 if (dictionary->IsKey(isolate, k)) {
1601 Object* value = dictionary->ValueAt(i);
1602 PropertyDetails details = dictionary->DetailsAt(i);
1603 SetDataOrAccessorPropertyReference(details.kind(), js_obj, entry,
1604 Name::cast(k), value);
1605 }
1606 }
1607 }
1608 }
1609
1610
ExtractAccessorPairProperty(JSObject * js_obj,int entry,Name * key,Object * callback_obj,int field_offset)1611 void V8HeapExplorer::ExtractAccessorPairProperty(JSObject* js_obj, int entry,
1612 Name* key,
1613 Object* callback_obj,
1614 int field_offset) {
1615 if (!callback_obj->IsAccessorPair()) return;
1616 AccessorPair* accessors = AccessorPair::cast(callback_obj);
1617 SetPropertyReference(js_obj, entry, key, accessors, NULL, field_offset);
1618 Object* getter = accessors->getter();
1619 if (!getter->IsOddball()) {
1620 SetPropertyReference(js_obj, entry, key, getter, "get %s");
1621 }
1622 Object* setter = accessors->setter();
1623 if (!setter->IsOddball()) {
1624 SetPropertyReference(js_obj, entry, key, setter, "set %s");
1625 }
1626 }
1627
1628
ExtractElementReferences(JSObject * js_obj,int entry)1629 void V8HeapExplorer::ExtractElementReferences(JSObject* js_obj, int entry) {
1630 Isolate* isolate = js_obj->GetIsolate();
1631 if (js_obj->HasFastObjectElements()) {
1632 FixedArray* elements = FixedArray::cast(js_obj->elements());
1633 int length = js_obj->IsJSArray() ?
1634 Smi::cast(JSArray::cast(js_obj)->length())->value() :
1635 elements->length();
1636 for (int i = 0; i < length; ++i) {
1637 if (!elements->get(i)->IsTheHole(isolate)) {
1638 SetElementReference(js_obj, entry, i, elements->get(i));
1639 }
1640 }
1641 } else if (js_obj->HasDictionaryElements()) {
1642 SeededNumberDictionary* dictionary = js_obj->element_dictionary();
1643 int length = dictionary->Capacity();
1644 for (int i = 0; i < length; ++i) {
1645 Object* k = dictionary->KeyAt(i);
1646 if (dictionary->IsKey(isolate, k)) {
1647 DCHECK(k->IsNumber());
1648 uint32_t index = static_cast<uint32_t>(k->Number());
1649 SetElementReference(js_obj, entry, index, dictionary->ValueAt(i));
1650 }
1651 }
1652 }
1653 }
1654
1655
ExtractInternalReferences(JSObject * js_obj,int entry)1656 void V8HeapExplorer::ExtractInternalReferences(JSObject* js_obj, int entry) {
1657 int length = js_obj->GetInternalFieldCount();
1658 for (int i = 0; i < length; ++i) {
1659 Object* o = js_obj->GetInternalField(i);
1660 SetInternalReference(
1661 js_obj, entry, i, o, js_obj->GetInternalFieldOffset(i));
1662 }
1663 }
1664
1665
GetConstructorName(JSObject * object)1666 String* V8HeapExplorer::GetConstructorName(JSObject* object) {
1667 Isolate* isolate = object->GetIsolate();
1668 if (object->IsJSFunction()) return isolate->heap()->closure_string();
1669 DisallowHeapAllocation no_gc;
1670 HandleScope scope(isolate);
1671 return *JSReceiver::GetConstructorName(handle(object, isolate));
1672 }
1673
1674
GetEntry(Object * obj)1675 HeapEntry* V8HeapExplorer::GetEntry(Object* obj) {
1676 if (!obj->IsHeapObject()) return NULL;
1677 return filler_->FindOrAddEntry(obj, this);
1678 }
1679
1680
1681 class RootsReferencesExtractor : public ObjectVisitor {
1682 private:
1683 struct IndexTag {
IndexTagv8::internal::RootsReferencesExtractor::IndexTag1684 IndexTag(int index, VisitorSynchronization::SyncTag tag)
1685 : index(index), tag(tag) { }
1686 int index;
1687 VisitorSynchronization::SyncTag tag;
1688 };
1689
1690 public:
RootsReferencesExtractor(Heap * heap)1691 explicit RootsReferencesExtractor(Heap* heap)
1692 : collecting_all_references_(false),
1693 previous_reference_count_(0),
1694 heap_(heap) {
1695 }
1696
VisitPointers(Object ** start,Object ** end)1697 void VisitPointers(Object** start, Object** end) override {
1698 if (collecting_all_references_) {
1699 for (Object** p = start; p < end; p++) all_references_.Add(*p);
1700 } else {
1701 for (Object** p = start; p < end; p++) strong_references_.Add(*p);
1702 }
1703 }
1704
SetCollectingAllReferences()1705 void SetCollectingAllReferences() { collecting_all_references_ = true; }
1706
FillReferences(V8HeapExplorer * explorer)1707 void FillReferences(V8HeapExplorer* explorer) {
1708 DCHECK(strong_references_.length() <= all_references_.length());
1709 Builtins* builtins = heap_->isolate()->builtins();
1710 int strong_index = 0, all_index = 0, tags_index = 0, builtin_index = 0;
1711 while (all_index < all_references_.length()) {
1712 bool is_strong = strong_index < strong_references_.length()
1713 && strong_references_[strong_index] == all_references_[all_index];
1714 explorer->SetGcSubrootReference(reference_tags_[tags_index].tag,
1715 !is_strong,
1716 all_references_[all_index]);
1717 if (reference_tags_[tags_index].tag ==
1718 VisitorSynchronization::kBuiltins) {
1719 DCHECK(all_references_[all_index]->IsCode());
1720 explorer->TagBuiltinCodeObject(
1721 Code::cast(all_references_[all_index]),
1722 builtins->name(builtin_index++));
1723 }
1724 ++all_index;
1725 if (is_strong) ++strong_index;
1726 if (reference_tags_[tags_index].index == all_index) ++tags_index;
1727 }
1728 }
1729
Synchronize(VisitorSynchronization::SyncTag tag)1730 void Synchronize(VisitorSynchronization::SyncTag tag) override {
1731 if (collecting_all_references_ &&
1732 previous_reference_count_ != all_references_.length()) {
1733 previous_reference_count_ = all_references_.length();
1734 reference_tags_.Add(IndexTag(previous_reference_count_, tag));
1735 }
1736 }
1737
1738 private:
1739 bool collecting_all_references_;
1740 List<Object*> strong_references_;
1741 List<Object*> all_references_;
1742 int previous_reference_count_;
1743 List<IndexTag> reference_tags_;
1744 Heap* heap_;
1745 };
1746
1747
IterateAndExtractReferences(SnapshotFiller * filler)1748 bool V8HeapExplorer::IterateAndExtractReferences(
1749 SnapshotFiller* filler) {
1750 filler_ = filler;
1751
1752 // Create references to the synthetic roots.
1753 SetRootGcRootsReference();
1754 for (int tag = 0; tag < VisitorSynchronization::kNumberOfSyncTags; tag++) {
1755 SetGcRootsReference(static_cast<VisitorSynchronization::SyncTag>(tag));
1756 }
1757
1758 // Make sure builtin code objects get their builtin tags
1759 // first. Otherwise a particular JSFunction object could set
1760 // its custom name to a generic builtin.
1761 RootsReferencesExtractor extractor(heap_);
1762 heap_->IterateRoots(&extractor, VISIT_ONLY_STRONG);
1763 extractor.SetCollectingAllReferences();
1764 heap_->IterateRoots(&extractor, VISIT_ALL);
1765 extractor.FillReferences(this);
1766
1767 // We have to do two passes as sometimes FixedArrays are used
1768 // to weakly hold their items, and it's impossible to distinguish
1769 // between these cases without processing the array owner first.
1770 bool interrupted =
1771 IterateAndExtractSinglePass<&V8HeapExplorer::ExtractReferencesPass1>() ||
1772 IterateAndExtractSinglePass<&V8HeapExplorer::ExtractReferencesPass2>();
1773
1774 if (interrupted) {
1775 filler_ = NULL;
1776 return false;
1777 }
1778
1779 filler_ = NULL;
1780 return progress_->ProgressReport(true);
1781 }
1782
1783
1784 template<V8HeapExplorer::ExtractReferencesMethod extractor>
IterateAndExtractSinglePass()1785 bool V8HeapExplorer::IterateAndExtractSinglePass() {
1786 // Now iterate the whole heap.
1787 bool interrupted = false;
1788 HeapIterator iterator(heap_, HeapIterator::kFilterUnreachable);
1789 // Heap iteration with filtering must be finished in any case.
1790 for (HeapObject* obj = iterator.next();
1791 obj != NULL;
1792 obj = iterator.next(), progress_->ProgressStep()) {
1793 if (interrupted) continue;
1794
1795 size_t max_pointer = obj->Size() / kPointerSize;
1796 if (max_pointer > marks_.size()) {
1797 // Clear the current bits.
1798 std::vector<bool>().swap(marks_);
1799 // Reallocate to right size.
1800 marks_.resize(max_pointer, false);
1801 }
1802
1803 HeapEntry* heap_entry = GetEntry(obj);
1804 int entry = heap_entry->index();
1805 if ((this->*extractor)(entry, obj)) {
1806 SetInternalReference(obj, entry,
1807 "map", obj->map(), HeapObject::kMapOffset);
1808 // Extract unvisited fields as hidden references and restore tags
1809 // of visited fields.
1810 IndexedReferencesExtractor refs_extractor(this, obj, entry);
1811 obj->Iterate(&refs_extractor);
1812 }
1813
1814 if (!progress_->ProgressReport(false)) interrupted = true;
1815 }
1816 return interrupted;
1817 }
1818
1819
IsEssentialObject(Object * object)1820 bool V8HeapExplorer::IsEssentialObject(Object* object) {
1821 return object->IsHeapObject() && !object->IsOddball() &&
1822 object != heap_->empty_byte_array() &&
1823 object != heap_->empty_fixed_array() &&
1824 object != heap_->empty_descriptor_array() &&
1825 object != heap_->empty_type_feedback_vector() &&
1826 object != heap_->fixed_array_map() && object != heap_->cell_map() &&
1827 object != heap_->global_property_cell_map() &&
1828 object != heap_->shared_function_info_map() &&
1829 object != heap_->free_space_map() &&
1830 object != heap_->one_pointer_filler_map() &&
1831 object != heap_->two_pointer_filler_map();
1832 }
1833
IsEssentialHiddenReference(Object * parent,int field_offset)1834 bool V8HeapExplorer::IsEssentialHiddenReference(Object* parent,
1835 int field_offset) {
1836 if (parent->IsAllocationSite() &&
1837 field_offset == AllocationSite::kWeakNextOffset)
1838 return false;
1839 if (parent->IsJSFunction() &&
1840 field_offset == JSFunction::kNextFunctionLinkOffset)
1841 return false;
1842 if (parent->IsCode() && field_offset == Code::kNextCodeLinkOffset)
1843 return false;
1844 if (parent->IsContext() &&
1845 field_offset == Context::OffsetOfElementAt(Context::NEXT_CONTEXT_LINK))
1846 return false;
1847 if (parent->IsWeakCell() && field_offset == WeakCell::kNextOffset)
1848 return false;
1849 return true;
1850 }
1851
SetContextReference(HeapObject * parent_obj,int parent_entry,String * reference_name,Object * child_obj,int field_offset)1852 void V8HeapExplorer::SetContextReference(HeapObject* parent_obj,
1853 int parent_entry,
1854 String* reference_name,
1855 Object* child_obj,
1856 int field_offset) {
1857 DCHECK(parent_entry == GetEntry(parent_obj)->index());
1858 HeapEntry* child_entry = GetEntry(child_obj);
1859 if (child_entry != NULL) {
1860 filler_->SetNamedReference(HeapGraphEdge::kContextVariable,
1861 parent_entry,
1862 names_->GetName(reference_name),
1863 child_entry);
1864 MarkVisitedField(parent_obj, field_offset);
1865 }
1866 }
1867
1868
MarkVisitedField(HeapObject * obj,int offset)1869 void V8HeapExplorer::MarkVisitedField(HeapObject* obj, int offset) {
1870 if (offset < 0) return;
1871 int index = offset / kPointerSize;
1872 DCHECK(!marks_[index]);
1873 marks_[index] = true;
1874 }
1875
1876
SetNativeBindReference(HeapObject * parent_obj,int parent_entry,const char * reference_name,Object * child_obj)1877 void V8HeapExplorer::SetNativeBindReference(HeapObject* parent_obj,
1878 int parent_entry,
1879 const char* reference_name,
1880 Object* child_obj) {
1881 DCHECK(parent_entry == GetEntry(parent_obj)->index());
1882 HeapEntry* child_entry = GetEntry(child_obj);
1883 if (child_entry != NULL) {
1884 filler_->SetNamedReference(HeapGraphEdge::kShortcut,
1885 parent_entry,
1886 reference_name,
1887 child_entry);
1888 }
1889 }
1890
1891
SetElementReference(HeapObject * parent_obj,int parent_entry,int index,Object * child_obj)1892 void V8HeapExplorer::SetElementReference(HeapObject* parent_obj,
1893 int parent_entry,
1894 int index,
1895 Object* child_obj) {
1896 DCHECK(parent_entry == GetEntry(parent_obj)->index());
1897 HeapEntry* child_entry = GetEntry(child_obj);
1898 if (child_entry != NULL) {
1899 filler_->SetIndexedReference(HeapGraphEdge::kElement,
1900 parent_entry,
1901 index,
1902 child_entry);
1903 }
1904 }
1905
1906
SetInternalReference(HeapObject * parent_obj,int parent_entry,const char * reference_name,Object * child_obj,int field_offset)1907 void V8HeapExplorer::SetInternalReference(HeapObject* parent_obj,
1908 int parent_entry,
1909 const char* reference_name,
1910 Object* child_obj,
1911 int field_offset) {
1912 DCHECK(parent_entry == GetEntry(parent_obj)->index());
1913 HeapEntry* child_entry = GetEntry(child_obj);
1914 if (child_entry == NULL) return;
1915 if (IsEssentialObject(child_obj)) {
1916 filler_->SetNamedReference(HeapGraphEdge::kInternal,
1917 parent_entry,
1918 reference_name,
1919 child_entry);
1920 }
1921 MarkVisitedField(parent_obj, field_offset);
1922 }
1923
1924
SetInternalReference(HeapObject * parent_obj,int parent_entry,int index,Object * child_obj,int field_offset)1925 void V8HeapExplorer::SetInternalReference(HeapObject* parent_obj,
1926 int parent_entry,
1927 int index,
1928 Object* child_obj,
1929 int field_offset) {
1930 DCHECK(parent_entry == GetEntry(parent_obj)->index());
1931 HeapEntry* child_entry = GetEntry(child_obj);
1932 if (child_entry == NULL) return;
1933 if (IsEssentialObject(child_obj)) {
1934 filler_->SetNamedReference(HeapGraphEdge::kInternal,
1935 parent_entry,
1936 names_->GetName(index),
1937 child_entry);
1938 }
1939 MarkVisitedField(parent_obj, field_offset);
1940 }
1941
SetHiddenReference(HeapObject * parent_obj,int parent_entry,int index,Object * child_obj,int field_offset)1942 void V8HeapExplorer::SetHiddenReference(HeapObject* parent_obj,
1943 int parent_entry, int index,
1944 Object* child_obj, int field_offset) {
1945 DCHECK(parent_entry == GetEntry(parent_obj)->index());
1946 HeapEntry* child_entry = GetEntry(child_obj);
1947 if (child_entry != nullptr && IsEssentialObject(child_obj) &&
1948 IsEssentialHiddenReference(parent_obj, field_offset)) {
1949 filler_->SetIndexedReference(HeapGraphEdge::kHidden, parent_entry, index,
1950 child_entry);
1951 }
1952 }
1953
1954
SetWeakReference(HeapObject * parent_obj,int parent_entry,const char * reference_name,Object * child_obj,int field_offset)1955 void V8HeapExplorer::SetWeakReference(HeapObject* parent_obj,
1956 int parent_entry,
1957 const char* reference_name,
1958 Object* child_obj,
1959 int field_offset) {
1960 DCHECK(parent_entry == GetEntry(parent_obj)->index());
1961 HeapEntry* child_entry = GetEntry(child_obj);
1962 if (child_entry == NULL) return;
1963 if (IsEssentialObject(child_obj)) {
1964 filler_->SetNamedReference(HeapGraphEdge::kWeak,
1965 parent_entry,
1966 reference_name,
1967 child_entry);
1968 }
1969 MarkVisitedField(parent_obj, field_offset);
1970 }
1971
1972
SetWeakReference(HeapObject * parent_obj,int parent_entry,int index,Object * child_obj,int field_offset)1973 void V8HeapExplorer::SetWeakReference(HeapObject* parent_obj,
1974 int parent_entry,
1975 int index,
1976 Object* child_obj,
1977 int field_offset) {
1978 DCHECK(parent_entry == GetEntry(parent_obj)->index());
1979 HeapEntry* child_entry = GetEntry(child_obj);
1980 if (child_entry == NULL) return;
1981 if (IsEssentialObject(child_obj)) {
1982 filler_->SetNamedReference(HeapGraphEdge::kWeak,
1983 parent_entry,
1984 names_->GetFormatted("%d", index),
1985 child_entry);
1986 }
1987 MarkVisitedField(parent_obj, field_offset);
1988 }
1989
1990
SetDataOrAccessorPropertyReference(PropertyKind kind,JSObject * parent_obj,int parent_entry,Name * reference_name,Object * child_obj,const char * name_format_string,int field_offset)1991 void V8HeapExplorer::SetDataOrAccessorPropertyReference(
1992 PropertyKind kind, JSObject* parent_obj, int parent_entry,
1993 Name* reference_name, Object* child_obj, const char* name_format_string,
1994 int field_offset) {
1995 if (kind == kAccessor) {
1996 ExtractAccessorPairProperty(parent_obj, parent_entry, reference_name,
1997 child_obj, field_offset);
1998 } else {
1999 SetPropertyReference(parent_obj, parent_entry, reference_name, child_obj,
2000 name_format_string, field_offset);
2001 }
2002 }
2003
2004
SetPropertyReference(HeapObject * parent_obj,int parent_entry,Name * reference_name,Object * child_obj,const char * name_format_string,int field_offset)2005 void V8HeapExplorer::SetPropertyReference(HeapObject* parent_obj,
2006 int parent_entry,
2007 Name* reference_name,
2008 Object* child_obj,
2009 const char* name_format_string,
2010 int field_offset) {
2011 DCHECK(parent_entry == GetEntry(parent_obj)->index());
2012 HeapEntry* child_entry = GetEntry(child_obj);
2013 if (child_entry != NULL) {
2014 HeapGraphEdge::Type type =
2015 reference_name->IsSymbol() || String::cast(reference_name)->length() > 0
2016 ? HeapGraphEdge::kProperty : HeapGraphEdge::kInternal;
2017 const char* name = name_format_string != NULL && reference_name->IsString()
2018 ? names_->GetFormatted(
2019 name_format_string,
2020 String::cast(reference_name)->ToCString(
2021 DISALLOW_NULLS, ROBUST_STRING_TRAVERSAL).get()) :
2022 names_->GetName(reference_name);
2023
2024 filler_->SetNamedReference(type,
2025 parent_entry,
2026 name,
2027 child_entry);
2028 MarkVisitedField(parent_obj, field_offset);
2029 }
2030 }
2031
2032
SetRootGcRootsReference()2033 void V8HeapExplorer::SetRootGcRootsReference() {
2034 filler_->SetIndexedAutoIndexReference(
2035 HeapGraphEdge::kElement,
2036 snapshot_->root()->index(),
2037 snapshot_->gc_roots());
2038 }
2039
2040
SetUserGlobalReference(Object * child_obj)2041 void V8HeapExplorer::SetUserGlobalReference(Object* child_obj) {
2042 HeapEntry* child_entry = GetEntry(child_obj);
2043 DCHECK(child_entry != NULL);
2044 filler_->SetNamedAutoIndexReference(
2045 HeapGraphEdge::kShortcut,
2046 snapshot_->root()->index(),
2047 child_entry);
2048 }
2049
2050
SetGcRootsReference(VisitorSynchronization::SyncTag tag)2051 void V8HeapExplorer::SetGcRootsReference(VisitorSynchronization::SyncTag tag) {
2052 filler_->SetIndexedAutoIndexReference(
2053 HeapGraphEdge::kElement,
2054 snapshot_->gc_roots()->index(),
2055 snapshot_->gc_subroot(tag));
2056 }
2057
2058
SetGcSubrootReference(VisitorSynchronization::SyncTag tag,bool is_weak,Object * child_obj)2059 void V8HeapExplorer::SetGcSubrootReference(
2060 VisitorSynchronization::SyncTag tag, bool is_weak, Object* child_obj) {
2061 HeapEntry* child_entry = GetEntry(child_obj);
2062 if (child_entry != NULL) {
2063 const char* name = GetStrongGcSubrootName(child_obj);
2064 if (name != NULL) {
2065 filler_->SetNamedReference(
2066 HeapGraphEdge::kInternal,
2067 snapshot_->gc_subroot(tag)->index(),
2068 name,
2069 child_entry);
2070 } else {
2071 if (is_weak) {
2072 filler_->SetNamedAutoIndexReference(
2073 HeapGraphEdge::kWeak,
2074 snapshot_->gc_subroot(tag)->index(),
2075 child_entry);
2076 } else {
2077 filler_->SetIndexedAutoIndexReference(
2078 HeapGraphEdge::kElement,
2079 snapshot_->gc_subroot(tag)->index(),
2080 child_entry);
2081 }
2082 }
2083
2084 // Add a shortcut to JS global object reference at snapshot root.
2085 if (child_obj->IsNativeContext()) {
2086 Context* context = Context::cast(child_obj);
2087 JSGlobalObject* global = context->global_object();
2088 if (global->IsJSGlobalObject()) {
2089 bool is_debug_object = false;
2090 is_debug_object = heap_->isolate()->debug()->IsDebugGlobal(global);
2091 if (!is_debug_object && !user_roots_.Contains(global)) {
2092 user_roots_.Insert(global);
2093 SetUserGlobalReference(global);
2094 }
2095 }
2096 }
2097 }
2098 }
2099
2100
GetStrongGcSubrootName(Object * object)2101 const char* V8HeapExplorer::GetStrongGcSubrootName(Object* object) {
2102 if (strong_gc_subroot_names_.is_empty()) {
2103 #define NAME_ENTRY(name) strong_gc_subroot_names_.SetTag(heap_->name(), #name);
2104 #define ROOT_NAME(type, name, camel_name) NAME_ENTRY(name)
2105 STRONG_ROOT_LIST(ROOT_NAME)
2106 #undef ROOT_NAME
2107 #define STRUCT_MAP_NAME(NAME, Name, name) NAME_ENTRY(name##_map)
2108 STRUCT_LIST(STRUCT_MAP_NAME)
2109 #undef STRUCT_MAP_NAME
2110 #define STRING_NAME(name, str) NAME_ENTRY(name)
2111 INTERNALIZED_STRING_LIST(STRING_NAME)
2112 #undef STRING_NAME
2113 #define SYMBOL_NAME(name) NAME_ENTRY(name)
2114 PRIVATE_SYMBOL_LIST(SYMBOL_NAME)
2115 #undef SYMBOL_NAME
2116 #define SYMBOL_NAME(name, description) NAME_ENTRY(name)
2117 PUBLIC_SYMBOL_LIST(SYMBOL_NAME)
2118 WELL_KNOWN_SYMBOL_LIST(SYMBOL_NAME)
2119 #undef SYMBOL_NAME
2120 #undef NAME_ENTRY
2121 CHECK(!strong_gc_subroot_names_.is_empty());
2122 }
2123 return strong_gc_subroot_names_.GetTag(object);
2124 }
2125
2126
TagObject(Object * obj,const char * tag)2127 void V8HeapExplorer::TagObject(Object* obj, const char* tag) {
2128 if (IsEssentialObject(obj)) {
2129 HeapEntry* entry = GetEntry(obj);
2130 if (entry->name()[0] == '\0') {
2131 entry->set_name(tag);
2132 }
2133 }
2134 }
2135
TagFixedArraySubType(const FixedArray * array,FixedArraySubInstanceType type)2136 void V8HeapExplorer::TagFixedArraySubType(const FixedArray* array,
2137 FixedArraySubInstanceType type) {
2138 DCHECK(array_types_.find(array) == array_types_.end());
2139 array_types_[array] = type;
2140 }
2141
2142 class GlobalObjectsEnumerator : public ObjectVisitor {
2143 public:
VisitPointers(Object ** start,Object ** end)2144 void VisitPointers(Object** start, Object** end) override {
2145 for (Object** p = start; p < end; p++) {
2146 if ((*p)->IsNativeContext()) {
2147 Context* context = Context::cast(*p);
2148 JSObject* proxy = context->global_proxy();
2149 if (proxy->IsJSGlobalProxy()) {
2150 Object* global = proxy->map()->prototype();
2151 if (global->IsJSGlobalObject()) {
2152 objects_.Add(Handle<JSGlobalObject>(JSGlobalObject::cast(global)));
2153 }
2154 }
2155 }
2156 }
2157 }
count()2158 int count() { return objects_.length(); }
at(int i)2159 Handle<JSGlobalObject>& at(int i) { return objects_[i]; }
2160
2161 private:
2162 List<Handle<JSGlobalObject> > objects_;
2163 };
2164
2165
2166 // Modifies heap. Must not be run during heap traversal.
TagGlobalObjects()2167 void V8HeapExplorer::TagGlobalObjects() {
2168 Isolate* isolate = heap_->isolate();
2169 HandleScope scope(isolate);
2170 GlobalObjectsEnumerator enumerator;
2171 isolate->global_handles()->IterateAllRoots(&enumerator);
2172 const char** urls = NewArray<const char*>(enumerator.count());
2173 for (int i = 0, l = enumerator.count(); i < l; ++i) {
2174 if (global_object_name_resolver_) {
2175 HandleScope scope(isolate);
2176 Handle<JSGlobalObject> global_obj = enumerator.at(i);
2177 urls[i] = global_object_name_resolver_->GetName(
2178 Utils::ToLocal(Handle<JSObject>::cast(global_obj)));
2179 } else {
2180 urls[i] = NULL;
2181 }
2182 }
2183
2184 DisallowHeapAllocation no_allocation;
2185 for (int i = 0, l = enumerator.count(); i < l; ++i) {
2186 objects_tags_.SetTag(*enumerator.at(i), urls[i]);
2187 }
2188
2189 DeleteArray(urls);
2190 }
2191
2192
2193 class GlobalHandlesExtractor : public ObjectVisitor {
2194 public:
GlobalHandlesExtractor(NativeObjectsExplorer * explorer)2195 explicit GlobalHandlesExtractor(NativeObjectsExplorer* explorer)
2196 : explorer_(explorer) {}
~GlobalHandlesExtractor()2197 ~GlobalHandlesExtractor() override {}
VisitPointers(Object ** start,Object ** end)2198 void VisitPointers(Object** start, Object** end) override { UNREACHABLE(); }
VisitEmbedderReference(Object ** p,uint16_t class_id)2199 void VisitEmbedderReference(Object** p, uint16_t class_id) override {
2200 explorer_->VisitSubtreeWrapper(p, class_id);
2201 }
2202 private:
2203 NativeObjectsExplorer* explorer_;
2204 };
2205
2206
2207 class BasicHeapEntriesAllocator : public HeapEntriesAllocator {
2208 public:
BasicHeapEntriesAllocator(HeapSnapshot * snapshot,HeapEntry::Type entries_type)2209 BasicHeapEntriesAllocator(
2210 HeapSnapshot* snapshot,
2211 HeapEntry::Type entries_type)
2212 : snapshot_(snapshot),
2213 names_(snapshot_->profiler()->names()),
2214 heap_object_map_(snapshot_->profiler()->heap_object_map()),
2215 entries_type_(entries_type) {
2216 }
2217 virtual HeapEntry* AllocateEntry(HeapThing ptr);
2218 private:
2219 HeapSnapshot* snapshot_;
2220 StringsStorage* names_;
2221 HeapObjectsMap* heap_object_map_;
2222 HeapEntry::Type entries_type_;
2223 };
2224
2225
AllocateEntry(HeapThing ptr)2226 HeapEntry* BasicHeapEntriesAllocator::AllocateEntry(HeapThing ptr) {
2227 v8::RetainedObjectInfo* info = reinterpret_cast<v8::RetainedObjectInfo*>(ptr);
2228 intptr_t elements = info->GetElementCount();
2229 intptr_t size = info->GetSizeInBytes();
2230 const char* name = elements != -1
2231 ? names_->GetFormatted("%s / %" V8PRIdPTR " entries",
2232 info->GetLabel(), elements)
2233 : names_->GetCopy(info->GetLabel());
2234 return snapshot_->AddEntry(
2235 entries_type_,
2236 name,
2237 heap_object_map_->GenerateId(info),
2238 size != -1 ? static_cast<int>(size) : 0,
2239 0);
2240 }
2241
2242
NativeObjectsExplorer(HeapSnapshot * snapshot,SnapshottingProgressReportingInterface * progress)2243 NativeObjectsExplorer::NativeObjectsExplorer(
2244 HeapSnapshot* snapshot,
2245 SnapshottingProgressReportingInterface* progress)
2246 : isolate_(snapshot->profiler()->heap_object_map()->heap()->isolate()),
2247 snapshot_(snapshot),
2248 names_(snapshot_->profiler()->names()),
2249 embedder_queried_(false),
2250 objects_by_info_(RetainedInfosMatch),
2251 native_groups_(StringsMatch),
2252 filler_(NULL) {
2253 synthetic_entries_allocator_ =
2254 new BasicHeapEntriesAllocator(snapshot, HeapEntry::kSynthetic);
2255 native_entries_allocator_ =
2256 new BasicHeapEntriesAllocator(snapshot, HeapEntry::kNative);
2257 }
2258
2259
~NativeObjectsExplorer()2260 NativeObjectsExplorer::~NativeObjectsExplorer() {
2261 for (base::HashMap::Entry* p = objects_by_info_.Start(); p != NULL;
2262 p = objects_by_info_.Next(p)) {
2263 v8::RetainedObjectInfo* info =
2264 reinterpret_cast<v8::RetainedObjectInfo*>(p->key);
2265 info->Dispose();
2266 List<HeapObject*>* objects =
2267 reinterpret_cast<List<HeapObject*>* >(p->value);
2268 delete objects;
2269 }
2270 for (base::HashMap::Entry* p = native_groups_.Start(); p != NULL;
2271 p = native_groups_.Next(p)) {
2272 v8::RetainedObjectInfo* info =
2273 reinterpret_cast<v8::RetainedObjectInfo*>(p->value);
2274 info->Dispose();
2275 }
2276 delete synthetic_entries_allocator_;
2277 delete native_entries_allocator_;
2278 }
2279
2280
EstimateObjectsCount()2281 int NativeObjectsExplorer::EstimateObjectsCount() {
2282 FillRetainedObjects();
2283 return objects_by_info_.occupancy();
2284 }
2285
2286
FillRetainedObjects()2287 void NativeObjectsExplorer::FillRetainedObjects() {
2288 if (embedder_queried_) return;
2289 Isolate* isolate = isolate_;
2290 const GCType major_gc_type = kGCTypeMarkSweepCompact;
2291 // Record objects that are joined into ObjectGroups.
2292 isolate->heap()->CallGCPrologueCallbacks(
2293 major_gc_type, kGCCallbackFlagConstructRetainedObjectInfos);
2294 List<ObjectGroup*>* groups = isolate->global_handles()->object_groups();
2295 for (int i = 0; i < groups->length(); ++i) {
2296 ObjectGroup* group = groups->at(i);
2297 if (group->info == NULL) continue;
2298 List<HeapObject*>* list = GetListMaybeDisposeInfo(group->info);
2299 for (size_t j = 0; j < group->length; ++j) {
2300 HeapObject* obj = HeapObject::cast(*group->objects[j]);
2301 list->Add(obj);
2302 in_groups_.Insert(obj);
2303 }
2304 group->info = NULL; // Acquire info object ownership.
2305 }
2306 isolate->global_handles()->RemoveObjectGroups();
2307 isolate->heap()->CallGCEpilogueCallbacks(major_gc_type, kNoGCCallbackFlags);
2308 // Record objects that are not in ObjectGroups, but have class ID.
2309 GlobalHandlesExtractor extractor(this);
2310 isolate->global_handles()->IterateAllRootsWithClassIds(&extractor);
2311 embedder_queried_ = true;
2312 }
2313
2314
FillImplicitReferences()2315 void NativeObjectsExplorer::FillImplicitReferences() {
2316 Isolate* isolate = isolate_;
2317 List<ImplicitRefGroup*>* groups =
2318 isolate->global_handles()->implicit_ref_groups();
2319 for (int i = 0; i < groups->length(); ++i) {
2320 ImplicitRefGroup* group = groups->at(i);
2321 HeapObject* parent = *group->parent;
2322 int parent_entry =
2323 filler_->FindOrAddEntry(parent, native_entries_allocator_)->index();
2324 DCHECK(parent_entry != HeapEntry::kNoEntry);
2325 Object*** children = group->children;
2326 for (size_t j = 0; j < group->length; ++j) {
2327 Object* child = *children[j];
2328 HeapEntry* child_entry =
2329 filler_->FindOrAddEntry(child, native_entries_allocator_);
2330 filler_->SetNamedReference(
2331 HeapGraphEdge::kInternal,
2332 parent_entry,
2333 "native",
2334 child_entry);
2335 }
2336 }
2337 isolate->global_handles()->RemoveImplicitRefGroups();
2338 }
2339
GetListMaybeDisposeInfo(v8::RetainedObjectInfo * info)2340 List<HeapObject*>* NativeObjectsExplorer::GetListMaybeDisposeInfo(
2341 v8::RetainedObjectInfo* info) {
2342 base::HashMap::Entry* entry =
2343 objects_by_info_.LookupOrInsert(info, InfoHash(info));
2344 if (entry->value != NULL) {
2345 info->Dispose();
2346 } else {
2347 entry->value = new List<HeapObject*>(4);
2348 }
2349 return reinterpret_cast<List<HeapObject*>* >(entry->value);
2350 }
2351
2352
IterateAndExtractReferences(SnapshotFiller * filler)2353 bool NativeObjectsExplorer::IterateAndExtractReferences(
2354 SnapshotFiller* filler) {
2355 filler_ = filler;
2356 FillRetainedObjects();
2357 FillImplicitReferences();
2358 if (EstimateObjectsCount() > 0) {
2359 for (base::HashMap::Entry* p = objects_by_info_.Start(); p != NULL;
2360 p = objects_by_info_.Next(p)) {
2361 v8::RetainedObjectInfo* info =
2362 reinterpret_cast<v8::RetainedObjectInfo*>(p->key);
2363 SetNativeRootReference(info);
2364 List<HeapObject*>* objects =
2365 reinterpret_cast<List<HeapObject*>* >(p->value);
2366 for (int i = 0; i < objects->length(); ++i) {
2367 SetWrapperNativeReferences(objects->at(i), info);
2368 }
2369 }
2370 SetRootNativeRootsReference();
2371 }
2372 filler_ = NULL;
2373 return true;
2374 }
2375
2376
2377 class NativeGroupRetainedObjectInfo : public v8::RetainedObjectInfo {
2378 public:
NativeGroupRetainedObjectInfo(const char * label)2379 explicit NativeGroupRetainedObjectInfo(const char* label)
2380 : disposed_(false),
2381 hash_(reinterpret_cast<intptr_t>(label)),
2382 label_(label) {
2383 }
2384
~NativeGroupRetainedObjectInfo()2385 virtual ~NativeGroupRetainedObjectInfo() {}
Dispose()2386 virtual void Dispose() {
2387 CHECK(!disposed_);
2388 disposed_ = true;
2389 delete this;
2390 }
IsEquivalent(RetainedObjectInfo * other)2391 virtual bool IsEquivalent(RetainedObjectInfo* other) {
2392 return hash_ == other->GetHash() && !strcmp(label_, other->GetLabel());
2393 }
GetHash()2394 virtual intptr_t GetHash() { return hash_; }
GetLabel()2395 virtual const char* GetLabel() { return label_; }
2396
2397 private:
2398 bool disposed_;
2399 intptr_t hash_;
2400 const char* label_;
2401 };
2402
2403
FindOrAddGroupInfo(const char * label)2404 NativeGroupRetainedObjectInfo* NativeObjectsExplorer::FindOrAddGroupInfo(
2405 const char* label) {
2406 const char* label_copy = names_->GetCopy(label);
2407 uint32_t hash = StringHasher::HashSequentialString(
2408 label_copy,
2409 static_cast<int>(strlen(label_copy)),
2410 isolate_->heap()->HashSeed());
2411 base::HashMap::Entry* entry =
2412 native_groups_.LookupOrInsert(const_cast<char*>(label_copy), hash);
2413 if (entry->value == NULL) {
2414 entry->value = new NativeGroupRetainedObjectInfo(label);
2415 }
2416 return static_cast<NativeGroupRetainedObjectInfo*>(entry->value);
2417 }
2418
2419
SetNativeRootReference(v8::RetainedObjectInfo * info)2420 void NativeObjectsExplorer::SetNativeRootReference(
2421 v8::RetainedObjectInfo* info) {
2422 HeapEntry* child_entry =
2423 filler_->FindOrAddEntry(info, native_entries_allocator_);
2424 DCHECK(child_entry != NULL);
2425 NativeGroupRetainedObjectInfo* group_info =
2426 FindOrAddGroupInfo(info->GetGroupLabel());
2427 HeapEntry* group_entry =
2428 filler_->FindOrAddEntry(group_info, synthetic_entries_allocator_);
2429 // |FindOrAddEntry| can move and resize the entries backing store. Reload
2430 // potentially-stale pointer.
2431 child_entry = filler_->FindEntry(info);
2432 filler_->SetNamedAutoIndexReference(
2433 HeapGraphEdge::kInternal,
2434 group_entry->index(),
2435 child_entry);
2436 }
2437
2438
SetWrapperNativeReferences(HeapObject * wrapper,v8::RetainedObjectInfo * info)2439 void NativeObjectsExplorer::SetWrapperNativeReferences(
2440 HeapObject* wrapper, v8::RetainedObjectInfo* info) {
2441 HeapEntry* wrapper_entry = filler_->FindEntry(wrapper);
2442 DCHECK(wrapper_entry != NULL);
2443 HeapEntry* info_entry =
2444 filler_->FindOrAddEntry(info, native_entries_allocator_);
2445 DCHECK(info_entry != NULL);
2446 filler_->SetNamedReference(HeapGraphEdge::kInternal,
2447 wrapper_entry->index(),
2448 "native",
2449 info_entry);
2450 filler_->SetIndexedAutoIndexReference(HeapGraphEdge::kElement,
2451 info_entry->index(),
2452 wrapper_entry);
2453 }
2454
2455
SetRootNativeRootsReference()2456 void NativeObjectsExplorer::SetRootNativeRootsReference() {
2457 for (base::HashMap::Entry* entry = native_groups_.Start(); entry;
2458 entry = native_groups_.Next(entry)) {
2459 NativeGroupRetainedObjectInfo* group_info =
2460 static_cast<NativeGroupRetainedObjectInfo*>(entry->value);
2461 HeapEntry* group_entry =
2462 filler_->FindOrAddEntry(group_info, native_entries_allocator_);
2463 DCHECK(group_entry != NULL);
2464 filler_->SetIndexedAutoIndexReference(
2465 HeapGraphEdge::kElement,
2466 snapshot_->root()->index(),
2467 group_entry);
2468 }
2469 }
2470
2471
VisitSubtreeWrapper(Object ** p,uint16_t class_id)2472 void NativeObjectsExplorer::VisitSubtreeWrapper(Object** p, uint16_t class_id) {
2473 if (in_groups_.Contains(*p)) return;
2474 Isolate* isolate = isolate_;
2475 v8::RetainedObjectInfo* info =
2476 isolate->heap_profiler()->ExecuteWrapperClassCallback(class_id, p);
2477 if (info == NULL) return;
2478 GetListMaybeDisposeInfo(info)->Add(HeapObject::cast(*p));
2479 }
2480
2481
HeapSnapshotGenerator(HeapSnapshot * snapshot,v8::ActivityControl * control,v8::HeapProfiler::ObjectNameResolver * resolver,Heap * heap)2482 HeapSnapshotGenerator::HeapSnapshotGenerator(
2483 HeapSnapshot* snapshot,
2484 v8::ActivityControl* control,
2485 v8::HeapProfiler::ObjectNameResolver* resolver,
2486 Heap* heap)
2487 : snapshot_(snapshot),
2488 control_(control),
2489 v8_heap_explorer_(snapshot_, this, resolver),
2490 dom_explorer_(snapshot_, this),
2491 heap_(heap) {
2492 }
2493
2494
GenerateSnapshot()2495 bool HeapSnapshotGenerator::GenerateSnapshot() {
2496 v8_heap_explorer_.TagGlobalObjects();
2497
2498 // TODO(1562) Profiler assumes that any object that is in the heap after
2499 // full GC is reachable from the root when computing dominators.
2500 // This is not true for weakly reachable objects.
2501 // As a temporary solution we call GC twice.
2502 heap_->CollectAllGarbage(Heap::kMakeHeapIterableMask,
2503 GarbageCollectionReason::kHeapProfiler);
2504 heap_->CollectAllGarbage(Heap::kMakeHeapIterableMask,
2505 GarbageCollectionReason::kHeapProfiler);
2506
2507 #ifdef VERIFY_HEAP
2508 Heap* debug_heap = heap_;
2509 if (FLAG_verify_heap) {
2510 debug_heap->Verify();
2511 }
2512 #endif
2513
2514 SetProgressTotal(2); // 2 passes.
2515
2516 #ifdef VERIFY_HEAP
2517 if (FLAG_verify_heap) {
2518 debug_heap->Verify();
2519 }
2520 #endif
2521
2522 snapshot_->AddSyntheticRootEntries();
2523
2524 if (!FillReferences()) return false;
2525
2526 snapshot_->FillChildren();
2527 snapshot_->RememberLastJSObjectId();
2528
2529 progress_counter_ = progress_total_;
2530 if (!ProgressReport(true)) return false;
2531 return true;
2532 }
2533
2534
ProgressStep()2535 void HeapSnapshotGenerator::ProgressStep() {
2536 ++progress_counter_;
2537 }
2538
2539
ProgressReport(bool force)2540 bool HeapSnapshotGenerator::ProgressReport(bool force) {
2541 const int kProgressReportGranularity = 10000;
2542 if (control_ != NULL
2543 && (force || progress_counter_ % kProgressReportGranularity == 0)) {
2544 return
2545 control_->ReportProgressValue(progress_counter_, progress_total_) ==
2546 v8::ActivityControl::kContinue;
2547 }
2548 return true;
2549 }
2550
2551
SetProgressTotal(int iterations_count)2552 void HeapSnapshotGenerator::SetProgressTotal(int iterations_count) {
2553 if (control_ == NULL) return;
2554 HeapIterator iterator(heap_, HeapIterator::kFilterUnreachable);
2555 progress_total_ = iterations_count * (
2556 v8_heap_explorer_.EstimateObjectsCount(&iterator) +
2557 dom_explorer_.EstimateObjectsCount());
2558 progress_counter_ = 0;
2559 }
2560
2561
FillReferences()2562 bool HeapSnapshotGenerator::FillReferences() {
2563 SnapshotFiller filler(snapshot_, &entries_);
2564 return v8_heap_explorer_.IterateAndExtractReferences(&filler)
2565 && dom_explorer_.IterateAndExtractReferences(&filler);
2566 }
2567
2568
2569 template<int bytes> struct MaxDecimalDigitsIn;
2570 template<> struct MaxDecimalDigitsIn<4> {
2571 static const int kSigned = 11;
2572 static const int kUnsigned = 10;
2573 };
2574 template<> struct MaxDecimalDigitsIn<8> {
2575 static const int kSigned = 20;
2576 static const int kUnsigned = 20;
2577 };
2578
2579
2580 class OutputStreamWriter {
2581 public:
OutputStreamWriter(v8::OutputStream * stream)2582 explicit OutputStreamWriter(v8::OutputStream* stream)
2583 : stream_(stream),
2584 chunk_size_(stream->GetChunkSize()),
2585 chunk_(chunk_size_),
2586 chunk_pos_(0),
2587 aborted_(false) {
2588 DCHECK(chunk_size_ > 0);
2589 }
aborted()2590 bool aborted() { return aborted_; }
AddCharacter(char c)2591 void AddCharacter(char c) {
2592 DCHECK(c != '\0');
2593 DCHECK(chunk_pos_ < chunk_size_);
2594 chunk_[chunk_pos_++] = c;
2595 MaybeWriteChunk();
2596 }
AddString(const char * s)2597 void AddString(const char* s) {
2598 AddSubstring(s, StrLength(s));
2599 }
AddSubstring(const char * s,int n)2600 void AddSubstring(const char* s, int n) {
2601 if (n <= 0) return;
2602 DCHECK(static_cast<size_t>(n) <= strlen(s));
2603 const char* s_end = s + n;
2604 while (s < s_end) {
2605 int s_chunk_size =
2606 Min(chunk_size_ - chunk_pos_, static_cast<int>(s_end - s));
2607 DCHECK(s_chunk_size > 0);
2608 MemCopy(chunk_.start() + chunk_pos_, s, s_chunk_size);
2609 s += s_chunk_size;
2610 chunk_pos_ += s_chunk_size;
2611 MaybeWriteChunk();
2612 }
2613 }
AddNumber(unsigned n)2614 void AddNumber(unsigned n) { AddNumberImpl<unsigned>(n, "%u"); }
Finalize()2615 void Finalize() {
2616 if (aborted_) return;
2617 DCHECK(chunk_pos_ < chunk_size_);
2618 if (chunk_pos_ != 0) {
2619 WriteChunk();
2620 }
2621 stream_->EndOfStream();
2622 }
2623
2624 private:
2625 template<typename T>
AddNumberImpl(T n,const char * format)2626 void AddNumberImpl(T n, const char* format) {
2627 // Buffer for the longest value plus trailing \0
2628 static const int kMaxNumberSize =
2629 MaxDecimalDigitsIn<sizeof(T)>::kUnsigned + 1;
2630 if (chunk_size_ - chunk_pos_ >= kMaxNumberSize) {
2631 int result = SNPrintF(
2632 chunk_.SubVector(chunk_pos_, chunk_size_), format, n);
2633 DCHECK(result != -1);
2634 chunk_pos_ += result;
2635 MaybeWriteChunk();
2636 } else {
2637 EmbeddedVector<char, kMaxNumberSize> buffer;
2638 int result = SNPrintF(buffer, format, n);
2639 USE(result);
2640 DCHECK(result != -1);
2641 AddString(buffer.start());
2642 }
2643 }
MaybeWriteChunk()2644 void MaybeWriteChunk() {
2645 DCHECK(chunk_pos_ <= chunk_size_);
2646 if (chunk_pos_ == chunk_size_) {
2647 WriteChunk();
2648 }
2649 }
WriteChunk()2650 void WriteChunk() {
2651 if (aborted_) return;
2652 if (stream_->WriteAsciiChunk(chunk_.start(), chunk_pos_) ==
2653 v8::OutputStream::kAbort) aborted_ = true;
2654 chunk_pos_ = 0;
2655 }
2656
2657 v8::OutputStream* stream_;
2658 int chunk_size_;
2659 ScopedVector<char> chunk_;
2660 int chunk_pos_;
2661 bool aborted_;
2662 };
2663
2664
2665 // type, name|index, to_node.
2666 const int HeapSnapshotJSONSerializer::kEdgeFieldsCount = 3;
2667 // type, name, id, self_size, edge_count, trace_node_id.
2668 const int HeapSnapshotJSONSerializer::kNodeFieldsCount = 6;
2669
Serialize(v8::OutputStream * stream)2670 void HeapSnapshotJSONSerializer::Serialize(v8::OutputStream* stream) {
2671 if (AllocationTracker* allocation_tracker =
2672 snapshot_->profiler()->allocation_tracker()) {
2673 allocation_tracker->PrepareForSerialization();
2674 }
2675 DCHECK(writer_ == NULL);
2676 writer_ = new OutputStreamWriter(stream);
2677 SerializeImpl();
2678 delete writer_;
2679 writer_ = NULL;
2680 }
2681
2682
SerializeImpl()2683 void HeapSnapshotJSONSerializer::SerializeImpl() {
2684 DCHECK(0 == snapshot_->root()->index());
2685 writer_->AddCharacter('{');
2686 writer_->AddString("\"snapshot\":{");
2687 SerializeSnapshot();
2688 if (writer_->aborted()) return;
2689 writer_->AddString("},\n");
2690 writer_->AddString("\"nodes\":[");
2691 SerializeNodes();
2692 if (writer_->aborted()) return;
2693 writer_->AddString("],\n");
2694 writer_->AddString("\"edges\":[");
2695 SerializeEdges();
2696 if (writer_->aborted()) return;
2697 writer_->AddString("],\n");
2698
2699 writer_->AddString("\"trace_function_infos\":[");
2700 SerializeTraceNodeInfos();
2701 if (writer_->aborted()) return;
2702 writer_->AddString("],\n");
2703 writer_->AddString("\"trace_tree\":[");
2704 SerializeTraceTree();
2705 if (writer_->aborted()) return;
2706 writer_->AddString("],\n");
2707
2708 writer_->AddString("\"samples\":[");
2709 SerializeSamples();
2710 if (writer_->aborted()) return;
2711 writer_->AddString("],\n");
2712
2713 writer_->AddString("\"strings\":[");
2714 SerializeStrings();
2715 if (writer_->aborted()) return;
2716 writer_->AddCharacter(']');
2717 writer_->AddCharacter('}');
2718 writer_->Finalize();
2719 }
2720
2721
GetStringId(const char * s)2722 int HeapSnapshotJSONSerializer::GetStringId(const char* s) {
2723 base::HashMap::Entry* cache_entry =
2724 strings_.LookupOrInsert(const_cast<char*>(s), StringHash(s));
2725 if (cache_entry->value == NULL) {
2726 cache_entry->value = reinterpret_cast<void*>(next_string_id_++);
2727 }
2728 return static_cast<int>(reinterpret_cast<intptr_t>(cache_entry->value));
2729 }
2730
2731
2732 namespace {
2733
2734 template<size_t size> struct ToUnsigned;
2735
2736 template<> struct ToUnsigned<4> {
2737 typedef uint32_t Type;
2738 };
2739
2740 template<> struct ToUnsigned<8> {
2741 typedef uint64_t Type;
2742 };
2743
2744 } // namespace
2745
2746
2747 template<typename T>
utoa_impl(T value,const Vector<char> & buffer,int buffer_pos)2748 static int utoa_impl(T value, const Vector<char>& buffer, int buffer_pos) {
2749 STATIC_ASSERT(static_cast<T>(-1) > 0); // Check that T is unsigned
2750 int number_of_digits = 0;
2751 T t = value;
2752 do {
2753 ++number_of_digits;
2754 } while (t /= 10);
2755
2756 buffer_pos += number_of_digits;
2757 int result = buffer_pos;
2758 do {
2759 int last_digit = static_cast<int>(value % 10);
2760 buffer[--buffer_pos] = '0' + last_digit;
2761 value /= 10;
2762 } while (value);
2763 return result;
2764 }
2765
2766
2767 template<typename T>
utoa(T value,const Vector<char> & buffer,int buffer_pos)2768 static int utoa(T value, const Vector<char>& buffer, int buffer_pos) {
2769 typename ToUnsigned<sizeof(value)>::Type unsigned_value = value;
2770 STATIC_ASSERT(sizeof(value) == sizeof(unsigned_value));
2771 return utoa_impl(unsigned_value, buffer, buffer_pos);
2772 }
2773
2774
SerializeEdge(HeapGraphEdge * edge,bool first_edge)2775 void HeapSnapshotJSONSerializer::SerializeEdge(HeapGraphEdge* edge,
2776 bool first_edge) {
2777 // The buffer needs space for 3 unsigned ints, 3 commas, \n and \0
2778 static const int kBufferSize =
2779 MaxDecimalDigitsIn<sizeof(unsigned)>::kUnsigned * 3 + 3 + 2; // NOLINT
2780 EmbeddedVector<char, kBufferSize> buffer;
2781 int edge_name_or_index = edge->type() == HeapGraphEdge::kElement
2782 || edge->type() == HeapGraphEdge::kHidden
2783 ? edge->index() : GetStringId(edge->name());
2784 int buffer_pos = 0;
2785 if (!first_edge) {
2786 buffer[buffer_pos++] = ',';
2787 }
2788 buffer_pos = utoa(edge->type(), buffer, buffer_pos);
2789 buffer[buffer_pos++] = ',';
2790 buffer_pos = utoa(edge_name_or_index, buffer, buffer_pos);
2791 buffer[buffer_pos++] = ',';
2792 buffer_pos = utoa(entry_index(edge->to()), buffer, buffer_pos);
2793 buffer[buffer_pos++] = '\n';
2794 buffer[buffer_pos++] = '\0';
2795 writer_->AddString(buffer.start());
2796 }
2797
2798
SerializeEdges()2799 void HeapSnapshotJSONSerializer::SerializeEdges() {
2800 List<HeapGraphEdge*>& edges = snapshot_->children();
2801 for (int i = 0; i < edges.length(); ++i) {
2802 DCHECK(i == 0 ||
2803 edges[i - 1]->from()->index() <= edges[i]->from()->index());
2804 SerializeEdge(edges[i], i == 0);
2805 if (writer_->aborted()) return;
2806 }
2807 }
2808
2809
SerializeNode(HeapEntry * entry)2810 void HeapSnapshotJSONSerializer::SerializeNode(HeapEntry* entry) {
2811 // The buffer needs space for 4 unsigned ints, 1 size_t, 5 commas, \n and \0
2812 static const int kBufferSize =
2813 5 * MaxDecimalDigitsIn<sizeof(unsigned)>::kUnsigned // NOLINT
2814 + MaxDecimalDigitsIn<sizeof(size_t)>::kUnsigned // NOLINT
2815 + 6 + 1 + 1;
2816 EmbeddedVector<char, kBufferSize> buffer;
2817 int buffer_pos = 0;
2818 if (entry_index(entry) != 0) {
2819 buffer[buffer_pos++] = ',';
2820 }
2821 buffer_pos = utoa(entry->type(), buffer, buffer_pos);
2822 buffer[buffer_pos++] = ',';
2823 buffer_pos = utoa(GetStringId(entry->name()), buffer, buffer_pos);
2824 buffer[buffer_pos++] = ',';
2825 buffer_pos = utoa(entry->id(), buffer, buffer_pos);
2826 buffer[buffer_pos++] = ',';
2827 buffer_pos = utoa(entry->self_size(), buffer, buffer_pos);
2828 buffer[buffer_pos++] = ',';
2829 buffer_pos = utoa(entry->children_count(), buffer, buffer_pos);
2830 buffer[buffer_pos++] = ',';
2831 buffer_pos = utoa(entry->trace_node_id(), buffer, buffer_pos);
2832 buffer[buffer_pos++] = '\n';
2833 buffer[buffer_pos++] = '\0';
2834 writer_->AddString(buffer.start());
2835 }
2836
2837
SerializeNodes()2838 void HeapSnapshotJSONSerializer::SerializeNodes() {
2839 List<HeapEntry>& entries = snapshot_->entries();
2840 for (int i = 0; i < entries.length(); ++i) {
2841 SerializeNode(&entries[i]);
2842 if (writer_->aborted()) return;
2843 }
2844 }
2845
2846
SerializeSnapshot()2847 void HeapSnapshotJSONSerializer::SerializeSnapshot() {
2848 writer_->AddString("\"meta\":");
2849 // The object describing node serialization layout.
2850 // We use a set of macros to improve readability.
2851 #define JSON_A(s) "[" s "]"
2852 #define JSON_O(s) "{" s "}"
2853 #define JSON_S(s) "\"" s "\""
2854 writer_->AddString(JSON_O(
2855 JSON_S("node_fields") ":" JSON_A(
2856 JSON_S("type") ","
2857 JSON_S("name") ","
2858 JSON_S("id") ","
2859 JSON_S("self_size") ","
2860 JSON_S("edge_count") ","
2861 JSON_S("trace_node_id")) ","
2862 JSON_S("node_types") ":" JSON_A(
2863 JSON_A(
2864 JSON_S("hidden") ","
2865 JSON_S("array") ","
2866 JSON_S("string") ","
2867 JSON_S("object") ","
2868 JSON_S("code") ","
2869 JSON_S("closure") ","
2870 JSON_S("regexp") ","
2871 JSON_S("number") ","
2872 JSON_S("native") ","
2873 JSON_S("synthetic") ","
2874 JSON_S("concatenated string") ","
2875 JSON_S("sliced string")) ","
2876 JSON_S("string") ","
2877 JSON_S("number") ","
2878 JSON_S("number") ","
2879 JSON_S("number") ","
2880 JSON_S("number") ","
2881 JSON_S("number")) ","
2882 JSON_S("edge_fields") ":" JSON_A(
2883 JSON_S("type") ","
2884 JSON_S("name_or_index") ","
2885 JSON_S("to_node")) ","
2886 JSON_S("edge_types") ":" JSON_A(
2887 JSON_A(
2888 JSON_S("context") ","
2889 JSON_S("element") ","
2890 JSON_S("property") ","
2891 JSON_S("internal") ","
2892 JSON_S("hidden") ","
2893 JSON_S("shortcut") ","
2894 JSON_S("weak")) ","
2895 JSON_S("string_or_number") ","
2896 JSON_S("node")) ","
2897 JSON_S("trace_function_info_fields") ":" JSON_A(
2898 JSON_S("function_id") ","
2899 JSON_S("name") ","
2900 JSON_S("script_name") ","
2901 JSON_S("script_id") ","
2902 JSON_S("line") ","
2903 JSON_S("column")) ","
2904 JSON_S("trace_node_fields") ":" JSON_A(
2905 JSON_S("id") ","
2906 JSON_S("function_info_index") ","
2907 JSON_S("count") ","
2908 JSON_S("size") ","
2909 JSON_S("children")) ","
2910 JSON_S("sample_fields") ":" JSON_A(
2911 JSON_S("timestamp_us") ","
2912 JSON_S("last_assigned_id"))));
2913 #undef JSON_S
2914 #undef JSON_O
2915 #undef JSON_A
2916 writer_->AddString(",\"node_count\":");
2917 writer_->AddNumber(snapshot_->entries().length());
2918 writer_->AddString(",\"edge_count\":");
2919 writer_->AddNumber(snapshot_->edges().length());
2920 writer_->AddString(",\"trace_function_count\":");
2921 uint32_t count = 0;
2922 AllocationTracker* tracker = snapshot_->profiler()->allocation_tracker();
2923 if (tracker) {
2924 count = tracker->function_info_list().length();
2925 }
2926 writer_->AddNumber(count);
2927 }
2928
2929
WriteUChar(OutputStreamWriter * w,unibrow::uchar u)2930 static void WriteUChar(OutputStreamWriter* w, unibrow::uchar u) {
2931 static const char hex_chars[] = "0123456789ABCDEF";
2932 w->AddString("\\u");
2933 w->AddCharacter(hex_chars[(u >> 12) & 0xf]);
2934 w->AddCharacter(hex_chars[(u >> 8) & 0xf]);
2935 w->AddCharacter(hex_chars[(u >> 4) & 0xf]);
2936 w->AddCharacter(hex_chars[u & 0xf]);
2937 }
2938
2939
SerializeTraceTree()2940 void HeapSnapshotJSONSerializer::SerializeTraceTree() {
2941 AllocationTracker* tracker = snapshot_->profiler()->allocation_tracker();
2942 if (!tracker) return;
2943 AllocationTraceTree* traces = tracker->trace_tree();
2944 SerializeTraceNode(traces->root());
2945 }
2946
2947
SerializeTraceNode(AllocationTraceNode * node)2948 void HeapSnapshotJSONSerializer::SerializeTraceNode(AllocationTraceNode* node) {
2949 // The buffer needs space for 4 unsigned ints, 4 commas, [ and \0
2950 const int kBufferSize =
2951 4 * MaxDecimalDigitsIn<sizeof(unsigned)>::kUnsigned // NOLINT
2952 + 4 + 1 + 1;
2953 EmbeddedVector<char, kBufferSize> buffer;
2954 int buffer_pos = 0;
2955 buffer_pos = utoa(node->id(), buffer, buffer_pos);
2956 buffer[buffer_pos++] = ',';
2957 buffer_pos = utoa(node->function_info_index(), buffer, buffer_pos);
2958 buffer[buffer_pos++] = ',';
2959 buffer_pos = utoa(node->allocation_count(), buffer, buffer_pos);
2960 buffer[buffer_pos++] = ',';
2961 buffer_pos = utoa(node->allocation_size(), buffer, buffer_pos);
2962 buffer[buffer_pos++] = ',';
2963 buffer[buffer_pos++] = '[';
2964 buffer[buffer_pos++] = '\0';
2965 writer_->AddString(buffer.start());
2966
2967 Vector<AllocationTraceNode*> children = node->children();
2968 for (int i = 0; i < children.length(); i++) {
2969 if (i > 0) {
2970 writer_->AddCharacter(',');
2971 }
2972 SerializeTraceNode(children[i]);
2973 }
2974 writer_->AddCharacter(']');
2975 }
2976
2977
2978 // 0-based position is converted to 1-based during the serialization.
SerializePosition(int position,const Vector<char> & buffer,int buffer_pos)2979 static int SerializePosition(int position, const Vector<char>& buffer,
2980 int buffer_pos) {
2981 if (position == -1) {
2982 buffer[buffer_pos++] = '0';
2983 } else {
2984 DCHECK(position >= 0);
2985 buffer_pos = utoa(static_cast<unsigned>(position + 1), buffer, buffer_pos);
2986 }
2987 return buffer_pos;
2988 }
2989
2990
SerializeTraceNodeInfos()2991 void HeapSnapshotJSONSerializer::SerializeTraceNodeInfos() {
2992 AllocationTracker* tracker = snapshot_->profiler()->allocation_tracker();
2993 if (!tracker) return;
2994 // The buffer needs space for 6 unsigned ints, 6 commas, \n and \0
2995 const int kBufferSize =
2996 6 * MaxDecimalDigitsIn<sizeof(unsigned)>::kUnsigned // NOLINT
2997 + 6 + 1 + 1;
2998 EmbeddedVector<char, kBufferSize> buffer;
2999 const List<AllocationTracker::FunctionInfo*>& list =
3000 tracker->function_info_list();
3001 for (int i = 0; i < list.length(); i++) {
3002 AllocationTracker::FunctionInfo* info = list[i];
3003 int buffer_pos = 0;
3004 if (i > 0) {
3005 buffer[buffer_pos++] = ',';
3006 }
3007 buffer_pos = utoa(info->function_id, buffer, buffer_pos);
3008 buffer[buffer_pos++] = ',';
3009 buffer_pos = utoa(GetStringId(info->name), buffer, buffer_pos);
3010 buffer[buffer_pos++] = ',';
3011 buffer_pos = utoa(GetStringId(info->script_name), buffer, buffer_pos);
3012 buffer[buffer_pos++] = ',';
3013 // The cast is safe because script id is a non-negative Smi.
3014 buffer_pos = utoa(static_cast<unsigned>(info->script_id), buffer,
3015 buffer_pos);
3016 buffer[buffer_pos++] = ',';
3017 buffer_pos = SerializePosition(info->line, buffer, buffer_pos);
3018 buffer[buffer_pos++] = ',';
3019 buffer_pos = SerializePosition(info->column, buffer, buffer_pos);
3020 buffer[buffer_pos++] = '\n';
3021 buffer[buffer_pos++] = '\0';
3022 writer_->AddString(buffer.start());
3023 }
3024 }
3025
3026
SerializeSamples()3027 void HeapSnapshotJSONSerializer::SerializeSamples() {
3028 const List<HeapObjectsMap::TimeInterval>& samples =
3029 snapshot_->profiler()->heap_object_map()->samples();
3030 if (samples.is_empty()) return;
3031 base::TimeTicks start_time = samples[0].timestamp;
3032 // The buffer needs space for 2 unsigned ints, 2 commas, \n and \0
3033 const int kBufferSize = MaxDecimalDigitsIn<sizeof(
3034 base::TimeDelta().InMicroseconds())>::kUnsigned +
3035 MaxDecimalDigitsIn<sizeof(samples[0].id)>::kUnsigned +
3036 2 + 1 + 1;
3037 EmbeddedVector<char, kBufferSize> buffer;
3038 for (int i = 0; i < samples.length(); i++) {
3039 HeapObjectsMap::TimeInterval& sample = samples[i];
3040 int buffer_pos = 0;
3041 if (i > 0) {
3042 buffer[buffer_pos++] = ',';
3043 }
3044 base::TimeDelta time_delta = sample.timestamp - start_time;
3045 buffer_pos = utoa(time_delta.InMicroseconds(), buffer, buffer_pos);
3046 buffer[buffer_pos++] = ',';
3047 buffer_pos = utoa(sample.last_assigned_id(), buffer, buffer_pos);
3048 buffer[buffer_pos++] = '\n';
3049 buffer[buffer_pos++] = '\0';
3050 writer_->AddString(buffer.start());
3051 }
3052 }
3053
3054
SerializeString(const unsigned char * s)3055 void HeapSnapshotJSONSerializer::SerializeString(const unsigned char* s) {
3056 writer_->AddCharacter('\n');
3057 writer_->AddCharacter('\"');
3058 for ( ; *s != '\0'; ++s) {
3059 switch (*s) {
3060 case '\b':
3061 writer_->AddString("\\b");
3062 continue;
3063 case '\f':
3064 writer_->AddString("\\f");
3065 continue;
3066 case '\n':
3067 writer_->AddString("\\n");
3068 continue;
3069 case '\r':
3070 writer_->AddString("\\r");
3071 continue;
3072 case '\t':
3073 writer_->AddString("\\t");
3074 continue;
3075 case '\"':
3076 case '\\':
3077 writer_->AddCharacter('\\');
3078 writer_->AddCharacter(*s);
3079 continue;
3080 default:
3081 if (*s > 31 && *s < 128) {
3082 writer_->AddCharacter(*s);
3083 } else if (*s <= 31) {
3084 // Special character with no dedicated literal.
3085 WriteUChar(writer_, *s);
3086 } else {
3087 // Convert UTF-8 into \u UTF-16 literal.
3088 size_t length = 1, cursor = 0;
3089 for ( ; length <= 4 && *(s + length) != '\0'; ++length) { }
3090 unibrow::uchar c = unibrow::Utf8::CalculateValue(s, length, &cursor);
3091 if (c != unibrow::Utf8::kBadChar) {
3092 WriteUChar(writer_, c);
3093 DCHECK(cursor != 0);
3094 s += cursor - 1;
3095 } else {
3096 writer_->AddCharacter('?');
3097 }
3098 }
3099 }
3100 }
3101 writer_->AddCharacter('\"');
3102 }
3103
3104
SerializeStrings()3105 void HeapSnapshotJSONSerializer::SerializeStrings() {
3106 ScopedVector<const unsigned char*> sorted_strings(
3107 strings_.occupancy() + 1);
3108 for (base::HashMap::Entry* entry = strings_.Start(); entry != NULL;
3109 entry = strings_.Next(entry)) {
3110 int index = static_cast<int>(reinterpret_cast<uintptr_t>(entry->value));
3111 sorted_strings[index] = reinterpret_cast<const unsigned char*>(entry->key);
3112 }
3113 writer_->AddString("\"<dummy>\"");
3114 for (int i = 1; i < sorted_strings.length(); ++i) {
3115 writer_->AddCharacter(',');
3116 SerializeString(sorted_strings[i]);
3117 if (writer_->aborted()) return;
3118 }
3119 }
3120
3121
3122 } // namespace internal
3123 } // namespace v8
3124