AuroraMiddleware/qt5base-lts
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Remove cast and assignment operators from QAtomicInt and QAtomicPointer

Browse Source 
This is a source incompatible change. There is concern that the
convenience of the implicit cast and assignment operators can lead to
misuse. Several commits have already been done that remove excess use
of the implicit cast, which is a *volatile* read every time it's used.

Users of the QAtomic* API should have to think about when they are
loading the value, and if they do or don't need the acquire memory
barrier on load. The code that people would write using this API is
meant to be multi-threaded, concurrent, and correct. The API should not
allow them to inadvertently, possibly unknowingly, shoot themselves
in the foot.

SC-break-rubber-stamped-by: Lars Knoll

Change-Id: I88fbc26d9db7b5ec80a58ad6271ffa13bbfd191f
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
This commit is contained in:
Bradley T. Hughes 2011-09-29 11:52:33 +02:00 committed by Qt by Nokia
parent 3a72240d86
commit 409b3b42a2
4 changed files with 10 additions and 221 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

68
src/corelib/thread/qatomic.h
View File

@ -78,43 +78,12 @@ public:
store(other.load());
}
Q_DECL_DEPRECATED
inline QAtomicInt &operator=(int value)
{
this->store(value);
return *this;
}
inline QAtomicInt &operator=(const QAtomicInt &other)
{
this->store(other.load());
return *this;
}
Q_DECL_DEPRECATED
inline bool operator==(int value) const
{
return this->load() == value;
}
Q_DECL_DEPRECATED
inline bool operator!=(int value) const
{
return this->load() != value;
}
Q_DECL_DEPRECATED
inline operator int() const
{
return this->load();
}
Q_DECL_DEPRECATED
inline bool operator!() const
{
return !this->load();
}
#ifdef qdoc
static bool isReferenceCountingNative();
static bool isReferenceCountingWaitFree();
@ -168,49 +137,12 @@ public:
this->store(other.load());
}
Q_DECL_DEPRECATED
inline QAtomicPointer<T> &operator=(T *value)
{
this->store(value);
return *this;
}
inline QAtomicPointer<T> &operator=(const QAtomicPointer<T> &other)
{
this->store(other.load());
return *this;
}
Q_DECL_DEPRECATED
inline bool operator==(T *value) const
{
return this->load() == value;
}
Q_DECL_DEPRECATED
inline bool operator!=(T *value) const
{
return this->load() != value;
}
Q_DECL_DEPRECATED
inline bool operator!() const
{
return !this->load();
}
Q_DECL_DEPRECATED
inline operator T *() const
{
return this->load();
}
Q_DECL_DEPRECATED
inline T *operator->() const
{
return this->load();
}
#ifdef qdoc
static bool isTestAndSetNative();
static bool isTestAndSetWaitFree();

77
tests/auto/corelib/thread/qatomicint/tst_qatomicint.cpp
View File

@ -61,14 +61,6 @@ private slots:
void constructor();
void copy_constructor_data();
void copy_constructor();
void equality_operator_data();
void equality_operator();
void inequality_operator_data();
void inequality_operator();
void not_operator_data();
void not_operator();
void cast_operator_data();
void cast_operator();
void assignment_operator_data();
void assignment_operator();
@ -185,71 +177,6 @@ void tst_QAtomicInt::copy_constructor()
QCOMPARE(atomic5.load(), value);
}
void tst_QAtomicInt::equality_operator_data()
{
QTest::addColumn<int>("value1");
QTest::addColumn<int>("value2");
QTest::addColumn<int>("result");
QTest::newRow("success0") << 1 << 1 << 1;
QTest::newRow("success1") << -1 << -1 << 1;
QTest::newRow("failure0") << 0 << 1 << 0;
QTest::newRow("failure1") << 1 << 0 << 0;
QTest::newRow("failure2") << 0 << -1 << 0;
QTest::newRow("failure3") << -1 << 0 << 0;
}
void tst_QAtomicInt::equality_operator()
{
QFETCH(int, value1);
QFETCH(int, value2);
QAtomicInt x = value1;
QTEST(x == value2 ? 1 : 0, "result");
}
void tst_QAtomicInt::inequality_operator_data()
{
QTest::addColumn<int>("value1");
QTest::addColumn<int>("value2");
QTest::addColumn<int>("result");
QTest::newRow("failure0") << 1 << 1 << 0;
QTest::newRow("failure1") << -1 << -1 << 0;
QTest::newRow("success0") << 0 << 1 << 1;
QTest::newRow("success1") << 1 << 0 << 1;
QTest::newRow("success2") << 0 << -1 << 1;
QTest::newRow("success3") << -1 << 0 << 1;
}
void tst_QAtomicInt::inequality_operator()
{
QFETCH(int, value1);
QFETCH(int, value2);
QAtomicInt x = value1;
QTEST(x != value2 ? 1 : 0, "result");
}
void tst_QAtomicInt::not_operator_data()
{ constructor_data(); }
void tst_QAtomicInt::not_operator()
{
QFETCH(int, value);
QAtomicInt atomic = value;
QCOMPARE(!atomic, !value);
}
void tst_QAtomicInt::cast_operator_data()
{ constructor_data(); }
void tst_QAtomicInt::cast_operator()
{
QFETCH(int, value);
QAtomicInt atomic = value;
int copy = atomic;
QCOMPARE(copy, value);
}
void tst_QAtomicInt::assignment_operator_data()
{
QTest::addColumn<int>("value");
@ -271,9 +198,9 @@ void tst_QAtomicInt::assignment_operator()
{
QAtomicInt atomic1 = value;
atomic1 = newval;
QCOMPARE(int(atomic1), newval);
QCOMPARE(atomic1.load(), newval);
atomic1 = value;
QCOMPARE(int(atomic1), value);
QCOMPARE(atomic1.load(), value);
QAtomicInt atomic2 = newval;
atomic1 = atomic2;

82
tests/auto/corelib/thread/qatomicpointer/tst_qatomicpointer.cpp
View File

@ -55,11 +55,7 @@ private slots:
void constructor();
void copy_constructor();
void equality_operator();
void inequality_operator();
void assignment_operator();
void star_operator();
void dereference_operator();
void isTestAndSetNative();
void isTestAndSetWaitFree();
@ -157,52 +153,6 @@ void tst_QAtomicPointer::copy_constructor()
QCOMPARE(atomic3_copy.load(), atomic3.load());
}
void tst_QAtomicPointer::equality_operator()
{
void *one = this;
void *two = &one;
void *three = &two;
QAtomicPointer<void> atomic1 = one;
QAtomicPointer<void> atomic2 = two;
QAtomicPointer<void> atomic3 = three;
QVERIFY(atomic1 == one);
QVERIFY(!(atomic1 == two));
QVERIFY(!(atomic1 == three));
QVERIFY(!(atomic2 == one));
QVERIFY(atomic2 == two);
QVERIFY(!(atomic2 == three));
QVERIFY(!(atomic3 == one));
QVERIFY(!(atomic3 == two));
QVERIFY(atomic3 == three);
}
void tst_QAtomicPointer::inequality_operator()
{
void *one = this;
void *two = &one;
void *three = &two;
QAtomicPointer<void> atomic1 = one;
QAtomicPointer<void> atomic2 = two;
QAtomicPointer<void> atomic3 = three;
QVERIFY(!(atomic1 != one));
QVERIFY(atomic1 != two);
QVERIFY(atomic1 != three);
QVERIFY(atomic2 != one);
QVERIFY(!(atomic2 != two));
QVERIFY(atomic2 != three);
QVERIFY(atomic3 != one);
QVERIFY(atomic3 != two);
QVERIFY(!(atomic3 != three));
}
void tst_QAtomicPointer::assignment_operator()
{
void *one = this;
@ -213,37 +163,17 @@ void tst_QAtomicPointer::assignment_operator()
QAtomicPointer<void> atomic2 = two;
QAtomicPointer<void> atomic3 = three;
QVERIFY(atomic1 == one);
QVERIFY(atomic2 == two);
QVERIFY(atomic3 == three);
QVERIFY(atomic1.load() == one);
QVERIFY(atomic2.load() == two);
QVERIFY(atomic3.load() == three);
atomic1 = two;
atomic2 = three;
atomic3 = one;
QVERIFY(atomic1 == two);
QVERIFY(atomic2 == three);
QVERIFY(atomic3 == one);
}
struct Type
{
inline const Type *self() const
{ return this; }
};
void tst_QAtomicPointer::star_operator()
{
Type t;
QAtomicPointer<Type> p = &t;
QCOMPARE((*p).self(), t.self());
}
void tst_QAtomicPointer::dereference_operator()
{
Type t;
QAtomicPointer<Type> p = &t;
QCOMPARE(p->self(), t.self());
QVERIFY(atomic1.load() == two);
QVERIFY(atomic2.load() == three);
QVERIFY(atomic3.load() == one);
}
void tst_QAtomicPointer::isTestAndSetNative()

4
tests/auto/corelib/tools/qsharedpointer/tst_qsharedpointer.cpp
View File

@ -1545,8 +1545,8 @@ void tst_QSharedPointer::threadStressTest()
// verify that the count is the right range
int minValue = strongThreadCount;
int maxValue = strongThreadCount + weakThreadCount;
QVERIFY(counter >= minValue);
QVERIFY(counter <= maxValue);
QVERIFY(counter.load() >= minValue);
QVERIFY(counter.load() <= maxValue);
}
}