Add reference-count manipulation functions to QArrayData and hide ref

The next change will stop using some values in the reference counter as
settings from the data.

Change-Id: I94df1fe643896373fac2f000fff55bc7708fc807
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

5 files changed, 51 insertions, 31 deletions

diff --git a/src/corelib/tools/qarraydata.cpp b/src/corelib/tools/qarraydata.cpp
index 3123d7467f..fdd441c7de 100644
--- a/src/corelib/tools/qarraydata.cpp
+++ b/src/corelib/tools/qarraydata.cpp
@@ -183,7 +183,7 @@ static QArrayData *allocateData(size_t allocSize, uint options)
 {
     QArrayData *header = static_cast<QArrayData *>(::malloc(allocSize));
     if (header) {
-        header->ref.atomic.storeRelaxed(1);
+        header->ref_.atomic.storeRelaxed(1);
         header->flags = options;
         header->size = 0;
     }
@@ -247,7 +247,7 @@ QArrayData *QArrayData::reallocateUnaligned(QArrayData *data, size_t objectSize,
 {
     Q_ASSERT(data);
     Q_ASSERT(data->isMutable());
-    Q_ASSERT(!data->ref.isShared());
+    Q_ASSERT(!data->isShared());
 
     options |= ArrayOption(AllocatedDataType);
     size_t headerSize = sizeof(QArrayData);
@@ -267,7 +267,7 @@ void QArrayData::deallocate(QArrayData *data, size_t objectSize,
             && !(alignment & (alignment - 1)));
     Q_UNUSED(objectSize) Q_UNUSED(alignment)
 
-    Q_ASSERT_X(data == 0 || !data->ref.isStatic(), "QArrayData::deallocate",
+    Q_ASSERT_X(data == 0 || !data->isStatic(), "QArrayData::deallocate",
                "Static data cannot be deleted");
     ::free(data);
 }
diff --git a/src/corelib/tools/qarraydata.h b/src/corelib/tools/qarraydata.h
index 8c21fd55c8..183cf9f002 100644
--- a/src/corelib/tools/qarraydata.h
+++ b/src/corelib/tools/qarraydata.h
@@ -67,7 +67,7 @@ struct Q_CORE_EXPORT QArrayData
     };
     Q_DECLARE_FLAGS(ArrayOptions, ArrayOption)
 
-    QtPrivate::RefCount ref;
+    QtPrivate::RefCount ref_;
     uint flags;
     int size;
     uint alloc;
@@ -84,6 +84,16 @@ struct Q_CORE_EXPORT QArrayData
         return alloc;
     }
 
+    bool ref()
+    {
+        return ref_.ref();
+    }
+
+    bool deref()
+    {
+        return ref_.deref();
+    }
+
     void *data()
     {
         Q_ASSERT(size == 0
@@ -106,13 +116,23 @@ struct Q_CORE_EXPORT QArrayData
         return flags & Mutable;
     }
 
+    bool isStatic() const
+    {
+        return ref_.isStatic();
+    }
+
+    bool isShared() const
+    {
+        return ref_.isShared();
+    }
+
     // Returns true if a detach is necessary before modifying the data
     // This method is intentionally not const: if you want to know whether
     // detaching is necessary, you should be in a non-const function already
     bool needsDetach()
     {
         // ### optimize me -- this currently requires 3 conditionals!
-        return !isMutable() || ref.isShared();
+        return !isMutable() || isShared();
     }
 
     size_t detachCapacity(size_t newSize) const
@@ -290,7 +310,7 @@ struct QTypedArrayData
         Q_STATIC_ASSERT(sizeof(QTypedArrayData) == sizeof(QArrayData));
         QTypedArrayData *result = static_cast<QTypedArrayData *>(prepareRawData(options));
         if (result) {
-            Q_ASSERT(!result->ref.isShared()); // No shared empty, please!
+            Q_ASSERT(!result->isShared()); // No shared empty, please!
 
             result->offset = reinterpret_cast<const char *>(data)
                 - reinterpret_cast<const char *>(result);
diff --git a/src/corelib/tools/qarraydataops.h b/src/corelib/tools/qarraydataops.h
index 7724049be8..777f0d839f 100644
--- a/src/corelib/tools/qarraydataops.h
+++ b/src/corelib/tools/qarraydataops.h
@@ -61,7 +61,7 @@ struct QPodArrayOps
     void appendInitialize(size_t newSize)
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(!this->ref.isShared());
+        Q_ASSERT(!this->isShared());
         Q_ASSERT(newSize > uint(this->size));
         Q_ASSERT(newSize <= this->allocatedCapacity());
 
@@ -72,7 +72,7 @@ struct QPodArrayOps
     void copyAppend(const T *b, const T *e)
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(!this->ref.isShared());
+        Q_ASSERT(!this->isShared());
         Q_ASSERT(b < e);
         Q_ASSERT(e - b <= this->allocatedCapacity() - this->size);
 
@@ -84,7 +84,7 @@ struct QPodArrayOps
     void copyAppend(size_t n, const T &t)
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(!this->ref.isShared());
+        Q_ASSERT(!this->isShared());
         Q_ASSERT(n <= uint(this->allocatedCapacity() - this->size));
 
         T *iter = this->end();
@@ -97,7 +97,7 @@ struct QPodArrayOps
     void truncate(size_t newSize)
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(!this->ref.isShared());
+        Q_ASSERT(!this->isShared());
         Q_ASSERT(newSize < size_t(this->size));
 
         this->size = int(newSize);
@@ -106,7 +106,7 @@ struct QPodArrayOps
     void destroyAll() // Call from destructors, ONLY!
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(this->ref.atomic.loadRelaxed() == 0);
+        Q_ASSERT(this->ref_.atomic.loadRelaxed() == 0);
 
         // As this is to be called only from destructor, it doesn't need to be
         // exception safe; size not updated.
@@ -115,7 +115,7 @@ struct QPodArrayOps
     void insert(T *where, const T *b, const T *e)
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(!this->ref.isShared());
+        Q_ASSERT(!this->isShared());
         Q_ASSERT(where >= this->begin() && where < this->end()); // Use copyAppend at end
         Q_ASSERT(b < e);
         Q_ASSERT(e <= where || b > this->end()); // No overlap
@@ -148,7 +148,7 @@ struct QGenericArrayOps
     void appendInitialize(size_t newSize)
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(!this->ref.isShared());
+        Q_ASSERT(!this->isShared());
         Q_ASSERT(newSize > uint(this->size));
         Q_ASSERT(newSize <= this->allocatedCapacity());
 
@@ -161,7 +161,7 @@ struct QGenericArrayOps
     void copyAppend(const T *b, const T *e)
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(!this->ref.isShared());
+        Q_ASSERT(!this->isShared());
         Q_ASSERT(b < e);
         Q_ASSERT(e - b <= this->allocatedCapacity() - this->size);
 
@@ -175,7 +175,7 @@ struct QGenericArrayOps
     void copyAppend(size_t n, const T &t)
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(!this->ref.isShared());
+        Q_ASSERT(!this->isShared());
         Q_ASSERT(n <= size_t(this->allocatedCapacity() - this->size));
 
         T *iter = this->end();
@@ -189,7 +189,7 @@ struct QGenericArrayOps
     void truncate(size_t newSize)
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(!this->ref.isShared());
+        Q_ASSERT(!this->isShared());
         Q_ASSERT(newSize < size_t(this->size));
 
         const T *const b = this->begin();
@@ -204,7 +204,7 @@ struct QGenericArrayOps
         // As this is to be called only from destructor, it doesn't need to be
         // exception safe; size not updated.
 
-        Q_ASSERT(this->ref.atomic.loadRelaxed() == 0);
+        Q_ASSERT(this->ref_.atomic.loadRelaxed() == 0);
 
         const T *const b = this->begin();
         const T *i = this->end();
@@ -216,7 +216,7 @@ struct QGenericArrayOps
     void insert(T *where, const T *b, const T *e)
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(!this->ref.isShared());
+        Q_ASSERT(!this->isShared());
         Q_ASSERT(where >= this->begin() && where < this->end()); // Use copyAppend at end
         Q_ASSERT(b < e);
         Q_ASSERT(e <= where || b > this->end()); // No overlap
@@ -312,7 +312,7 @@ struct QMovableArrayOps
     void insert(T *where, const T *b, const T *e)
     {
         Q_ASSERT(this->isMutable());
-        Q_ASSERT(!this->ref.isShared());
+        Q_ASSERT(!this->isShared());
         Q_ASSERT(where >= this->begin() && where < this->end()); // Use copyAppend at end
         Q_ASSERT(b < e);
         Q_ASSERT(e <= where || b > this->end()); // No overlap
diff --git a/src/corelib/tools/qarraydatapointer.h b/src/corelib/tools/qarraydatapointer.h
index b7236d485a..86997985d1 100644
--- a/src/corelib/tools/qarraydatapointer.h
+++ b/src/corelib/tools/qarraydatapointer.h
@@ -58,7 +58,7 @@ public:
     }
 
     QArrayDataPointer(const QArrayDataPointer &other)
-        : d(other.d->ref.ref()
+        : d(other.d->ref()
             ? other.d
             : other.clone(other.d->cloneFlags()))
     {
@@ -109,7 +109,7 @@ public:
 
     ~QArrayDataPointer()
     {
-        if (!d->ref.deref()) {
+        if (!d->deref()) {
             if (d->isMutable())
                 (*this)->destroyAll();
             Data::deallocate(d);
diff --git a/src/corelib/tools/qvector.h b/src/corelib/tools/qvector.h
index a596beedcf..d9512ee90e 100644
--- a/src/corelib/tools/qvector.h
+++ b/src/corelib/tools/qvector.h
@@ -89,7 +89,7 @@ public:
     explicit QVector(int size);
     QVector(int size, const T &t);
     inline QVector(const QVector<T> &v);
-    inline ~QVector() { if (!d->ref.deref()) freeData(d); }
+    inline ~QVector() { if (!d->deref()) freeData(d); }
     QVector<T> &operator=(const QVector<T> &v);
     QVector(QVector<T> &&other) noexcept : d(other.d) { other.d = Data::sharedNull(); }
     QVector<T> &operator=(QVector<T> &&other) noexcept
@@ -114,17 +114,17 @@ public:
     void reserve(int size);
     inline void squeeze()
     {
-        if (d->size < int(d->alloc)) {
+        if (d->size < int(d->allocatedCapacity())) {
             if (!d->size) {
                 *this = QVector<T>();
                 return;
             }
-            realloc(d->size, QArrayData::ArrayOptions(d->flags));
+            realloc(d->size, d->detachFlags());
         }
     }
 
     inline void detach();
-    inline bool isDetached() const { return !d->ref.isShared(); }
+    inline bool isDetached() const { return !d->isShared(); }
 
     inline bool isSharedWith(const QVector<T> &other) const { return d == other.d; }
 
@@ -365,7 +365,7 @@ void QVector<T>::destruct(T *from, T *to)
 template <typename T>
 inline QVector<T>::QVector(const QVector<T> &v)
 {
-    if (v.d->ref.ref()) {
+    if (v.d->ref()) {
         d = v.d;
     } else {
         if (v.d->flags & Data::CapacityReserved) {
@@ -391,7 +391,7 @@ template <typename T>
 void QVector<T>::detach()
 {
     // ### check whether this is still required
-    if (d->ref.isStatic())
+    if (d->isStatic())
         return;
 
     if (d->needsDetach())
@@ -581,14 +581,14 @@ void QVector<T>::realloc(int aalloc, QArrayData::ArrayOptions options)
     Q_ASSERT(aalloc >= d->size);
     Data *x = d;
 
-    const bool isShared = d->ref.isShared();
+    const bool isShared = d->isShared();
 
     QT_TRY {
         // allocate memory
         x = Data::allocate(aalloc, options);
         Q_CHECK_PTR(x);
         // aalloc is bigger then 0 so it is not [un]sharedEmpty
-        Q_ASSERT(!x->ref.isStatic());
+        Q_ASSERT(!x->isStatic());
         x->size = d->size;
 
         T *srcBegin = d->begin();
@@ -621,7 +621,7 @@ void QVector<T>::realloc(int aalloc, QArrayData::ArrayOptions options)
     }
 
     Q_ASSERT(d != x);
-    if (!d->ref.deref()) {
+    if (!d->deref()) {
         if (!QTypeInfoQuery<T>::isRelocatable || !aalloc || (isShared && QTypeInfo<T>::isComplex)) {
             // data was copy constructed, we need to call destructors
             // or if !alloc we did nothing to the old 'd'.
@@ -701,7 +701,7 @@ void QVector<T>::removeLast()
     Q_ASSERT(!isEmpty());
     Q_ASSERT(d->allocatedCapacity());
 
-    if (d->ref.isShared())
+    if (d->isShared())
         detach();
     --d->size;
     if (QTypeInfo<T>::isComplex)