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40
41#ifndef QATOMIC_BOOTSTRAP_H
42#define QATOMIC_BOOTSTRAP_H
43
44#include <QtCore/qgenericatomic.h>
45
46QT_BEGIN_NAMESPACE
47
48#if 0
49// silence syncqt warnings
50QT_END_NAMESPACE
51#pragma qt_sync_skip_header_check
52#pragma qt_sync_stop_processing
53#endif
54
55template <typename T> struct QAtomicOps: QGenericAtomicOps<QAtomicOps<T> >
56{
57 typedef T Type;
58
59 static bool ref(T &_q_value) noexcept
60 {
61 return ++_q_value != 0;
62 }
63 static bool deref(T &_q_value) noexcept
64 {
65 return --_q_value != 0;
66 }
67
68 static bool testAndSetRelaxed(T &_q_value, T expectedValue, T newValue, T *currentValue = nullptr) noexcept
69 {
70 if (currentValue)
71 *currentValue = _q_value;
72 if (_q_value == expectedValue) {
73 _q_value = newValue;
74 return true;
75 }
76 return false;
77 }
78
79 static T fetchAndStoreRelaxed(T &_q_value, T newValue) noexcept
80 {
81 T tmp = _q_value;
82 _q_value = newValue;
83 return tmp;
84 }
85
86 template <typename AdditiveType> static
87 T fetchAndAddRelaxed(T &_q_value, AdditiveType valueToAdd) noexcept
88 {
89 T returnValue = _q_value;
90 _q_value += valueToAdd;
91 return returnValue;
92 }
93};
94
95QT_END_NAMESPACE
96
97#endif // QATOMIC_BOOTSTRAP_H
98

source code of qtbase/src/corelib/thread/qatomic_bootstrap.h