1// Copyright 2015 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/heap/array-buffer-tracker.h"
6#include "src/heap/heap.h"
7#include "src/isolate.h"
8#include "src/objects.h"
9#include "src/objects-inl.h"
10#include "src/v8.h"
11
12namespace v8 {
13namespace internal {
14
15ArrayBufferTracker::~ArrayBufferTracker() {
16  Isolate* isolate = heap()->isolate();
17  size_t freed_memory = 0;
18  for (auto& buffer : live_array_buffers_) {
19    isolate->array_buffer_allocator()->Free(buffer.first, buffer.second);
20    freed_memory += buffer.second;
21  }
22  for (auto& buffer : live_array_buffers_for_scavenge_) {
23    isolate->array_buffer_allocator()->Free(buffer.first, buffer.second);
24    freed_memory += buffer.second;
25  }
26  live_array_buffers_.clear();
27  live_array_buffers_for_scavenge_.clear();
28  not_yet_discovered_array_buffers_.clear();
29  not_yet_discovered_array_buffers_for_scavenge_.clear();
30
31  if (freed_memory > 0) {
32    heap()->update_amount_of_external_allocated_memory(
33        -static_cast<int64_t>(freed_memory));
34  }
35}
36
37
38void ArrayBufferTracker::RegisterNew(JSArrayBuffer* buffer) {
39  void* data = buffer->backing_store();
40  if (!data) return;
41
42  bool in_new_space = heap()->InNewSpace(buffer);
43  size_t length = NumberToSize(heap()->isolate(), buffer->byte_length());
44  if (in_new_space) {
45    live_array_buffers_for_scavenge_[data] = length;
46  } else {
47    live_array_buffers_[data] = length;
48  }
49
50  // We may go over the limit of externally allocated memory here. We call the
51  // api function to trigger a GC in this case.
52  reinterpret_cast<v8::Isolate*>(heap()->isolate())
53      ->AdjustAmountOfExternalAllocatedMemory(length);
54}
55
56
57void ArrayBufferTracker::Unregister(JSArrayBuffer* buffer) {
58  void* data = buffer->backing_store();
59  if (!data) return;
60
61  bool in_new_space = heap()->InNewSpace(buffer);
62  std::map<void*, size_t>* live_buffers =
63      in_new_space ? &live_array_buffers_for_scavenge_ : &live_array_buffers_;
64  std::map<void*, size_t>* not_yet_discovered_buffers =
65      in_new_space ? &not_yet_discovered_array_buffers_for_scavenge_
66                   : &not_yet_discovered_array_buffers_;
67
68  DCHECK(live_buffers->count(data) > 0);
69
70  size_t length = (*live_buffers)[data];
71  live_buffers->erase(data);
72  not_yet_discovered_buffers->erase(data);
73
74  heap()->update_amount_of_external_allocated_memory(
75      -static_cast<int64_t>(length));
76}
77
78
79void ArrayBufferTracker::MarkLive(JSArrayBuffer* buffer) {
80  void* data = buffer->backing_store();
81
82  // ArrayBuffer might be in the middle of being constructed.
83  if (data == heap()->undefined_value()) return;
84  if (heap()->InNewSpace(buffer)) {
85    not_yet_discovered_array_buffers_for_scavenge_.erase(data);
86  } else {
87    not_yet_discovered_array_buffers_.erase(data);
88  }
89}
90
91
92void ArrayBufferTracker::FreeDead(bool from_scavenge) {
93  size_t freed_memory = 0;
94  Isolate* isolate = heap()->isolate();
95  for (auto& buffer : not_yet_discovered_array_buffers_for_scavenge_) {
96    isolate->array_buffer_allocator()->Free(buffer.first, buffer.second);
97    freed_memory += buffer.second;
98    live_array_buffers_for_scavenge_.erase(buffer.first);
99  }
100
101  if (!from_scavenge) {
102    for (auto& buffer : not_yet_discovered_array_buffers_) {
103      isolate->array_buffer_allocator()->Free(buffer.first, buffer.second);
104      freed_memory += buffer.second;
105      live_array_buffers_.erase(buffer.first);
106    }
107  }
108
109  not_yet_discovered_array_buffers_for_scavenge_ =
110      live_array_buffers_for_scavenge_;
111  if (!from_scavenge) not_yet_discovered_array_buffers_ = live_array_buffers_;
112
113  // Do not call through the api as this code is triggered while doing a GC.
114  heap()->update_amount_of_external_allocated_memory(
115      -static_cast<int64_t>(freed_memory));
116}
117
118
119void ArrayBufferTracker::PrepareDiscoveryInNewSpace() {
120  not_yet_discovered_array_buffers_for_scavenge_ =
121      live_array_buffers_for_scavenge_;
122}
123
124
125void ArrayBufferTracker::Promote(JSArrayBuffer* buffer) {
126  if (buffer->is_external()) return;
127  void* data = buffer->backing_store();
128  if (!data) return;
129  // ArrayBuffer might be in the middle of being constructed.
130  if (data == heap()->undefined_value()) return;
131  DCHECK(live_array_buffers_for_scavenge_.count(data) > 0);
132  live_array_buffers_[data] = live_array_buffers_for_scavenge_[data];
133  live_array_buffers_for_scavenge_.erase(data);
134  not_yet_discovered_array_buffers_for_scavenge_.erase(data);
135}
136
137}  // namespace internal
138}  // namespace v8
139