V8 API Reference, 7.2.502.16 (for Deno 0.2.4)
incremental-marking-inl.h
1 // Copyright 2012 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 #ifndef V8_HEAP_INCREMENTAL_MARKING_INL_H_
6 #define V8_HEAP_INCREMENTAL_MARKING_INL_H_
7 
8 #include "src/heap/incremental-marking.h"
9 
10 #include "src/heap/mark-compact-inl.h"
11 #include "src/isolate.h"
12 #include "src/objects-inl.h"
13 #include "src/objects/maybe-object.h"
14 
15 namespace v8 {
16 namespace internal {
17 
18 void IncrementalMarking::TransferColor(HeapObject* from, HeapObject* to) {
19  if (atomic_marking_state()->IsBlack(to)) {
20  DCHECK(black_allocation());
21  return;
22  }
23 
24  DCHECK(atomic_marking_state()->IsWhite(to));
25  if (atomic_marking_state()->IsGrey(from)) {
26  bool success = atomic_marking_state()->WhiteToGrey(to);
27  DCHECK(success);
28  USE(success);
29  } else if (atomic_marking_state()->IsBlack(from)) {
30  bool success = atomic_marking_state()->WhiteToBlack(to);
31  DCHECK(success);
32  USE(success);
33  }
34 }
35 
36 void IncrementalMarking::RecordWrite(HeapObject* obj, ObjectSlot slot,
37  Object* value) {
38  DCHECK_IMPLIES(slot.address() != kNullAddress, !HasWeakHeapObjectTag(*slot));
39  DCHECK(!HasWeakHeapObjectTag(value));
40  if (IsMarking() && value->IsHeapObject()) {
41  RecordWriteSlow(obj, HeapObjectSlot(slot), HeapObject::cast(value));
42  }
43 }
44 
45 void IncrementalMarking::RecordMaybeWeakWrite(HeapObject* obj,
46  MaybeObjectSlot slot,
47  MaybeObject value) {
48  // When writing a weak reference, treat it as strong for the purposes of the
49  // marking barrier.
50  HeapObject* heap_object;
51  if (IsMarking() && value->GetHeapObject(&heap_object)) {
52  RecordWriteSlow(obj, HeapObjectSlot(slot), heap_object);
53  }
54 }
55 
56 void IncrementalMarking::RestartIfNotMarking() {
57  if (state_ == COMPLETE) {
58  state_ = MARKING;
59  if (FLAG_trace_incremental_marking) {
60  heap()->isolate()->PrintWithTimestamp(
61  "[IncrementalMarking] Restarting (new grey objects)\n");
62  }
63  }
64 }
65 
66 } // namespace internal
67 } // namespace v8
68 
69 #endif // V8_HEAP_INCREMENTAL_MARKING_INL_H_
Definition: libplatform.h:13