Pass QMetaType by value

Now that QMetaType is not refcounted anymore, we can and should
pass it by value.

Change-Id: I848db65070713762f548ca949097c27783aacad4
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/kernel/qmetatype.cpp

@@ -806,7 +806,7 @@ void QMetaType::unregisterMetaType(QMetaType type)
     Returns the QMetaType corresponding to the type in the template parameter.
 */
 
-/*! \fn bool operator==(const QMetaType &a, const QMetaType &b)
+/*! \fn bool operator==(QMetaType a, QMetaType b)
     \since 5.15
     \relates QMetaType
     \overload
@@ -815,7 +815,7 @@ void QMetaType::unregisterMetaType(QMetaType type)
     as the QMetaType \a b, otherwise returns \c false.
 */
 
-/*! \fn bool operator!=(const QMetaType &a, const QMetaType &b)
+/*! \fn bool operator!=(QMetaType a, QMetaType b)
     \since 5.15
     \relates QMetaType
     \overload
@@ -1714,7 +1714,7 @@ static QMetaEnum metaEnumFromType(QMetaType t)
 }
 #endif
 
-static bool convertFromEnum(const QMetaType &fromType, const void *from, QMetaType toType, void *to)
+static bool convertFromEnum(QMetaType fromType, const void *from, QMetaType toType, void *to)
 {
     qlonglong ll;
     if (fromType.flags() & QMetaType::IsUnsignedEnumeration) {
@@ -1966,7 +1966,7 @@ static bool convertToAssociativeIterable(QMetaType fromType, const void *from, v
 
 
 #ifndef QT_BOOTSTRAPPED
-static bool canConvertMetaObject(const QMetaType &fromType, const QMetaType &toType)
+static bool canConvertMetaObject(QMetaType fromType, QMetaType toType)
 {
     if ((fromType.flags() & QMetaType::PointerToQObject) && (toType.flags() & QMetaType::PointerToQObject)) {
         return fromType.metaObject()->inherits(toType.metaObject()) ||
@@ -2128,7 +2128,7 @@ bool QMetaType::convert(QMetaType fromType, const void *from, QMetaType toType,
     \sa convert(), QSequentialIterable, Q_DECLARE_SEQUENTIAL_CONTAINER_METATYPE(), QAssociativeIterable,
         Q_DECLARE_ASSOCIATIVE_CONTAINER_METATYPE()
 */
-bool QMetaType::canConvert(const QMetaType &fromType, const QMetaType &toType)
+bool QMetaType::canConvert(QMetaType fromType, QMetaType toType)
 {
     int fromTypeId = fromType.id();
     int toTypeId = toType.id();

src/corelib/kernel/qmetatype.h

@@ -438,8 +438,8 @@ public:
     static QMetaType fromType();
     static QMetaType fromName(QByteArrayView name);
 
-    friend bool operator==(const QMetaType &a, const QMetaType &b) { return a.id() == b.id(); }
+    friend bool operator==(QMetaType a, QMetaType b) { return a.id() == b.id(); }
-    friend bool operator!=(const QMetaType &a, const QMetaType &b) { return !(a == b); }
+    friend bool operator!=(QMetaType a, QMetaType b) { return !(a == b); }
 
 public:
 
@@ -538,7 +538,7 @@ public:
 #endif
 
     static bool convert(QMetaType fromType, const void *from, QMetaType toType, void *to);
-    static bool canConvert(const QMetaType &fromType, const QMetaType &toType);
+    static bool canConvert(QMetaType fromType, QMetaType toType);
 #if QT_DEPRECATED_SINCE(6, 0)
     QT_DEPRECATED_VERSION_6_0
     static bool convert(const void *from, int fromTypeId, void *to, int toTypeId)

src/corelib/kernel/qproperty.cpp

@@ -150,7 +150,7 @@ bool QPropertyBindingPrivate::evaluateIfDirtyAndReturnTrueIfValueChanged()
 
 QUntypedPropertyBinding::QUntypedPropertyBinding() = default;
 
-QUntypedPropertyBinding::QUntypedPropertyBinding(const QMetaType &metaType, QUntypedPropertyBinding::BindingEvaluationFunction function,
+QUntypedPropertyBinding::QUntypedPropertyBinding(QMetaType metaType, QUntypedPropertyBinding::BindingEvaluationFunction function,
                                                  const QPropertyBindingSourceLocation &location)
 {
     d = new QPropertyBindingPrivate(metaType, std::move(function), std::move(location));

src/corelib/kernel/qproperty.h

@@ -43,7 +43,6 @@
 #include <QtCore/qglobal.h>
 #include <QtCore/QSharedDataPointer>
 #include <QtCore/QString>
-#include <QtCore/qmetatype.h>
 #include <functional>
 #include <type_traits>
 #include <variant>
@@ -123,7 +122,7 @@ public:
     using BindingEvaluationFunction = QtPrivate::QPropertyBindingFunction;
 
     QUntypedPropertyBinding();
-    QUntypedPropertyBinding(const QMetaType &metaType, BindingEvaluationFunction function, const QPropertyBindingSourceLocation &location);
+    QUntypedPropertyBinding(QMetaType metaType, BindingEvaluationFunction function, const QPropertyBindingSourceLocation &location);
     QUntypedPropertyBinding(QUntypedPropertyBinding &&other);
     QUntypedPropertyBinding(const QUntypedPropertyBinding &other);
     QUntypedPropertyBinding &operator=(const QUntypedPropertyBinding &other);
@@ -151,7 +150,7 @@ class QPropertyBinding : public QUntypedPropertyBinding
     struct BindingAdaptor
     {
         Functor impl;
-        bool operator()(const QMetaType &/*metaType*/, void *dataPtr)
+        bool operator()(QMetaType /*metaType*/, void *dataPtr)
         {
             PropertyType *propertyPtr = static_cast<PropertyType *>(dataPtr);
             PropertyType newValue = impl();

src/corelib/kernel/qproperty_p.h

@@ -166,7 +166,7 @@ public:
     // public because the auto-tests access it, too.
     size_t dependencyObserverCount = 0;
 
-    QPropertyBindingPrivate(const QMetaType &metaType, QUntypedPropertyBinding::BindingEvaluationFunction evaluationFunction,
+    QPropertyBindingPrivate(QMetaType metaType, QUntypedPropertyBinding::BindingEvaluationFunction evaluationFunction,
                             const QPropertyBindingSourceLocation &location)
         : isBool(metaType.id() == QMetaType::Bool)
         , evaluationFunction(std::move(evaluationFunction))

src/corelib/kernel/qpropertyprivate.h

@@ -54,6 +54,7 @@
 #include <QtCore/qglobal.h>
 #include <QtCore/QExplicitlySharedDataPointer>
 #include <QtCore/qtaggedpointer.h>
+#include <QtCore/qmetatype.h>
 
 #include <functional>
 
@@ -63,14 +64,13 @@ class QUntypedPropertyBinding;
 class QPropertyBindingPrivate;
 using QPropertyBindingPrivatePtr = QExplicitlySharedDataPointer<QPropertyBindingPrivate>;
 struct QPropertyBasePointer;
-class QMetaType;
 
 namespace QtPrivate {
 
 // writes binding result into dataPtr
-using QPropertyBindingFunction = std::function<bool(const QMetaType &metaType, void *dataPtr)>;
+using QPropertyBindingFunction = std::function<bool(QMetaType metaType, void *dataPtr)>;
 
-using QPropertyGuardFunction = bool(*)(const QMetaType &, void *dataPtr,
+using QPropertyGuardFunction = bool(*)(QMetaType, void *dataPtr,
                                        QPropertyBindingFunction, void *owner);
 using QPropertyObserverCallback = void (*)(void *, void *);
 
@@ -242,7 +242,7 @@ struct QPropertyGuardFunctionHelper
 template<typename T, typename Class, auto Guard>
 struct QPropertyGuardFunctionHelper<T, Class, Guard, false>
 {
-    static auto guard(const QMetaType &metaType, void *dataPtr,
+    static auto guard(const QMetaType metaType, void *dataPtr,
                       QPropertyBindingFunction eval, void *owner) -> bool
     {
         T t = T();

src/corelib/kernel/qvariant.h

@@ -443,7 +443,7 @@ class Q_CORE_EXPORT QVariant
         quintptr packedType : sizeof(QMetaType) * 8 - 2;
 
         Private() noexcept : is_shared(false), is_null(true), packedType(0) {}
-        explicit Private(const QMetaType &type) noexcept : is_shared(false), is_null(false)
+        explicit Private(QMetaType type) noexcept : is_shared(false), is_null(false)
         {
             quintptr mt = quintptr(type.d_ptr);
             Q_ASSERT((mt & 0x3) == 0);