1 // Copyright 2016 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/conversions-inl.h"
6 #include "src/heap/array-buffer-tracker.h"
7 #include "src/heap/heap.h"
8 #include "src/objects.h"
9
10 namespace v8 {
11 namespace internal {
12
RegisterNew(Heap * heap,JSArrayBuffer * buffer)13 void ArrayBufferTracker::RegisterNew(Heap* heap, JSArrayBuffer* buffer) {
14 void* data = buffer->backing_store();
15 if (!data) return;
16
17 size_t length = NumberToSize(heap->isolate(), buffer->byte_length());
18 Page* page = Page::FromAddress(buffer->address());
19 {
20 base::LockGuard<base::Mutex> guard(page->mutex());
21 LocalArrayBufferTracker* tracker = page->local_tracker();
22 if (tracker == nullptr) {
23 page->AllocateLocalTracker();
24 tracker = page->local_tracker();
25 }
26 DCHECK_NOT_NULL(tracker);
27 tracker->Add(buffer, std::make_pair(data, length));
28 }
29 // We may go over the limit of externally allocated memory here. We call the
30 // api function to trigger a GC in this case.
31 reinterpret_cast<v8::Isolate*>(heap->isolate())
32 ->AdjustAmountOfExternalAllocatedMemory(length);
33 }
34
Unregister(Heap * heap,JSArrayBuffer * buffer)35 void ArrayBufferTracker::Unregister(Heap* heap, JSArrayBuffer* buffer) {
36 void* data = buffer->backing_store();
37 if (!data) return;
38
39 Page* page = Page::FromAddress(buffer->address());
40 size_t length = 0;
41 {
42 base::LockGuard<base::Mutex> guard(page->mutex());
43 LocalArrayBufferTracker* tracker = page->local_tracker();
44 DCHECK_NOT_NULL(tracker);
45 length = tracker->Remove(buffer).second;
46 }
47 heap->update_external_memory(-static_cast<intptr_t>(length));
48 }
49
Add(Key key,const Value & value)50 void LocalArrayBufferTracker::Add(Key key, const Value& value) {
51 auto ret = array_buffers_.insert(std::make_pair(key, value));
52 USE(ret);
53 // Check that we indeed inserted a new value and did not overwrite an existing
54 // one (which would be a bug).
55 DCHECK(ret.second);
56 }
57
Remove(Key key)58 LocalArrayBufferTracker::Value LocalArrayBufferTracker::Remove(Key key) {
59 TrackingMap::iterator it = array_buffers_.find(key);
60 DCHECK(it != array_buffers_.end());
61 Value value = it->second;
62 array_buffers_.erase(it);
63 return value;
64 }
65
66 } // namespace internal
67 } // namespace v8
68