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39#ifndef QV4WRITEBARRIER_P_H
40#define QV4WRITEBARRIER_P_H
41
42//
43// W A R N I N G
44// -------------
45//
46// This file is not part of the Qt API. It exists purely as an
47// implementation detail. This header file may change from version to
48// version without notice, or even be removed.
49//
50// We mean it.
51//
52
53#include <private/qv4global_p.h>
54
55QT_BEGIN_NAMESPACE
56
57#define WRITEBARRIER_none 1
58
59#define WRITEBARRIER(x) (1/WRITEBARRIER_##x == 1)
60
61namespace QV4 {
62struct EngineBase;
63
64namespace WriteBarrier {
65
66enum Type {
67 NoBarrier,
68 Barrier
69};
70
71enum NewValueType {
72 Primitive,
73 Object,
74 Unknown
75};
76
77// ### this needs to be filled with a real memory fence once marking is concurrent
78Q_ALWAYS_INLINE void fence() {}
79
80#if WRITEBARRIER(none)
81
82template <NewValueType type>
83static Q_CONSTEXPR inline bool isRequired() {
84 return false;
85}
86
87inline void write(EngineBase *engine, Heap::Base *base, ReturnedValue *slot, ReturnedValue value)
88{
89 Q_UNUSED(engine);
90 Q_UNUSED(base);
91 *slot = value;
92}
93
94inline void write(EngineBase *engine, Heap::Base *base, Heap::Base **slot, Heap::Base *value)
95{
96 Q_UNUSED(engine);
97 Q_UNUSED(base);
98 *slot = value;
99}
100
101#endif
102
103}
104
105}
106
107QT_END_NAMESPACE
108
109#endif
110

source code of qtdeclarative/src/qml/memory/qv4writebarrier_p.h