Improve memory usage of the connectionlists inside QObject

... by not allocating space for slots in the vector.

Before, the vector uses the signal index as index. The problem is that
the slots and signal are mixed in the same index space.

We solve the problem by having a different index space for the signal in
the connectionlists vector.  All we need to do is to add the information
about the number of signals in the moc.

Also, we are not connecting to cloned signal but only to the orginial
ones.  For example,  destroyed(QObject * = 0) would generate two signal,
we now only connect to the first one.

This also improve a little bit the performence while activating signals
since it removed one call to indexOfMethod.

Reviewed-by: Brad

2 files changed, 8 insertions, 9 deletions

diff --git a/src/corelib/animation/qvariantanimation.cpp b/src/corelib/animation/qvariantanimation.cpp
index fc11815..696a95a 100644
--- a/src/corelib/animation/qvariantanimation.cpp
+++ b/src/corelib/animation/qvariantanimation.cpp
@@ -137,7 +137,6 @@ QT_BEGIN_NAMESPACE
     \sa currentValue
 */
 
-
 static bool animationValueLessThan(const QVariantAnimation::KeyValue &p1, const QVariantAnimation::KeyValue &p2)
 {
     return p1.first < p2.first;
@@ -178,11 +177,8 @@ template<> Q_INLINE_TEMPLATE QLineF _q_interpolate(const QLineF &f, const QLineF
     return QLineF( _q_interpolate(f.p1(), t.p1(), progress), _q_interpolate(f.p2(), t.p2(), progress));
 }
 
-QVariantAnimationPrivate::QVariantAnimationPrivate() : duration(250), interpolator(&defaultInterpolator),
-                          changedSignalMask(1 << QVariantAnimation::staticMetaObject.indexOfSignal("valueChanged(QVariant)"))
-{
-    //we keep the mask so that we emit valueChanged only when needed (for performance reasons)
-}
+QVariantAnimationPrivate::QVariantAnimationPrivate() : duration(250), interpolator(&defaultInterpolator)
+{ }
 
 void QVariantAnimationPrivate::convertValues(int t)
 {
@@ -278,7 +274,12 @@ void QVariantAnimationPrivate::setCurrentValueForProgress(const qreal progress)
                                    localProgress);
     qSwap(currentValue, ret);
     q->updateCurrentValue(currentValue);
-    if ((connectedSignals[0] & changedSignalMask) && currentValue != ret) {
+    static QBasicAtomicInt changedSignalIndex = Q_BASIC_ATOMIC_INITIALIZER(0);
+    if (!changedSignalIndex) {
+        //we keep the mask so that we emit valueChanged only when needed (for performance reasons)
+        changedSignalIndex.testAndSetRelaxed(0, signalIndex("valueChanged(QVariant)"));
+    }
+    if (isSignalConnected(changedSignalIndex) && currentValue != ret) {
         //the value has changed
         emit q->valueChanged(currentValue);
     }
diff --git a/src/corelib/animation/qvariantanimation_p.h b/src/corelib/animation/qvariantanimation_p.h
index ef57a4c..ce625f1 100644
--- a/src/corelib/animation/qvariantanimation_p.h
+++ b/src/corelib/animation/qvariantanimation_p.h
@@ -93,8 +93,6 @@ public:
 
     QVariantAnimation::Interpolator interpolator;
 
-    const quint32 changedSignalMask;
-
     void setCurrentValueForProgress(const qreal progress);
     void recalculateCurrentInterval(bool force=false);
     void setValueAt(qreal, const QVariant &);