Introduce internal StateType to avoid excessive qobject_casts

The state machine algorithm frequently needs to know what type a state
is, e.g. if it is atomic, final or a history state. We were using
qobject_cast() to determine this, but that function is expensive.
This commit introduces an internal StateType to be able to differentiate
between the different types of state. This vastly improves performance.

Reviewed-by: Eskil Abrahamsen Blomfeldt

1 files changed, 8 insertions, 3 deletions

diff --git a/src/corelib/statemachine/qabstractstate.cpp b/src/corelib/statemachine/qabstractstate.cpp
index cf67cdd..ec5332f 100644
--- a/src/corelib/statemachine/qabstractstate.cpp
+++ b/src/corelib/statemachine/qabstractstate.cpp
@@ -78,8 +78,8 @@ QT_BEGIN_NAMESPACE
   function to perform custom processing when the state is exited.
 */
 
-QAbstractStatePrivate::QAbstractStatePrivate()
-    : parentState(0)
+QAbstractStatePrivate::QAbstractStatePrivate(StateType type)
+    : stateType(type), isMachine(false), parentState(0)
 {
 }
 
@@ -88,6 +88,11 @@ QAbstractStatePrivate *QAbstractStatePrivate::get(QAbstractState *q)
     return q->d_func();
 }
 
+const QAbstractStatePrivate *QAbstractStatePrivate::get(const QAbstractState *q)
+{
+    return q->d_func();
+}
+
 QStateMachine *QAbstractStatePrivate::machine() const
 {
     QObject *par = parent;
@@ -127,7 +132,7 @@ void QAbstractStatePrivate::emitExited()
   Constructs a new state with the given \a parent state.
 */
 QAbstractState::QAbstractState(QState *parent)
-    : QObject(*new QAbstractStatePrivate, parent)
+    : QObject(*new QAbstractStatePrivate(QAbstractStatePrivate::AbstractState), parent)
 {
 }