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27
28#ifndef V8_UNBOUND_QUEUE_
29#define V8_UNBOUND_QUEUE_
30
31#include "allocation.h"
32
33namespace v8 {
34namespace internal {
35
36
37// Lock-free unbound queue for small records.  Intended for
38// transferring small records between a Single producer and a Single
39// consumer. Doesn't have restrictions on the number of queued
40// elements, so producer never blocks.  Implemented after Herb
41// Sutter's article:
42// http://www.ddj.com/high-performance-computing/210604448
43template<typename Record>
44class UnboundQueue BASE_EMBEDDED {
45 public:
46  inline UnboundQueue();
47  inline ~UnboundQueue();
48
49  INLINE(void Dequeue(Record* rec));
50  INLINE(void Enqueue(const Record& rec));
51  INLINE(bool IsEmpty()) { return divider_ == last_; }
52  INLINE(Record* Peek());
53
54 private:
55  INLINE(void DeleteFirst());
56
57  struct Node;
58
59  Node* first_;
60  AtomicWord divider_;  // Node*
61  AtomicWord last_;     // Node*
62
63  DISALLOW_COPY_AND_ASSIGN(UnboundQueue);
64};
65
66
67} }  // namespace v8::internal
68
69#endif  // V8_UNBOUND_QUEUE_
70