Use QStringRef to optimize memory allocation

Replace substring functions that return QString with
corresponding functions that return QStringRef where
it's possible.

Create QString from QStringRef only where necessary.

While touching the code, also port loops to C++11 style.

Change-Id: I04c99b24ea6afd3715e3edf9ea00bfab838fd53c
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>
Reviewed-by: Frank Meerkoetter <frank.meerkoetter@basyskom.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@theqtcompany.com>
Reviewed-by: Robin Burchell <robin.burchell@viroteck.net>

1 files changed, 9 insertions, 7 deletions

diff --git a/src/qml/qml/qqmlproperty.cpp b/src/qml/qml/qqmlproperty.cpp
index 22de5e1ae9..df2ff05de1 100644
--- a/src/qml/qml/qqmlproperty.cpp
+++ b/src/qml/qml/qqmlproperty.cpp
@@ -58,6 +58,7 @@
 #include <private/qv4functionobject_p.h>
 
 #include <QStringList>
+#include <QVector>
 #include <private/qmetaobject_p.h>
 #include <private/qqmlvaluetypewrapper_p.h>
 #include <QtCore/qdebug.h>
@@ -240,14 +241,14 @@ void QQmlPropertyPrivate::initProperty(QObject *obj, const QString &name)
 
     QQmlTypeNameCache *typeNameCache = context?context->imports:0;
 
-    QStringList path = name.split(QLatin1Char('.'));
+    const auto path = name.splitRef(QLatin1Char('.'));
     if (path.isEmpty()) return;
 
     QObject *currentObject = obj;
 
     // Everything up to the last property must be an "object type" property
     for (int ii = 0; ii < path.count() - 1; ++ii) {
-        const QString &pathName = path.at(ii);
+        const QStringRef &pathName = path.at(ii);
 
         if (typeNameCache) {
             QQmlTypeNameCache::Result r = typeNameCache->query(pathName);
@@ -284,7 +285,7 @@ void QQmlPropertyPrivate::initProperty(QObject *obj, const QString &name)
 
         QQmlPropertyData local;
         QQmlPropertyData *property =
-            QQmlPropertyCache::property(engine, currentObject, pathName, context, local);
+            QQmlPropertyCache::property(engine, currentObject, pathName.toString(), context, local);
 
         if (!property) return; // Not a property
         if (property->isFunction())
@@ -324,14 +325,14 @@ void QQmlPropertyPrivate::initProperty(QObject *obj, const QString &name)
 
     }
 
-    const QString &terminal = path.last();
+    const QStringRef &terminal = path.last();
 
     if (terminal.count() >= 3 &&
         terminal.at(0) == QLatin1Char('o') &&
         terminal.at(1) == QLatin1Char('n') &&
         terminal.at(2).isUpper()) {
 
-        QString signalName = terminal.mid(2);
+        QString signalName = terminal.mid(2).toString();
         signalName[0] = signalName.at(0).toLower();
 
         // XXX - this code treats methods as signals
@@ -376,13 +377,14 @@ void QQmlPropertyPrivate::initProperty(QObject *obj, const QString &name)
     }
 
     // Property
+    const QString terminalString = terminal.toString();
     QQmlPropertyData local;
     QQmlPropertyData *property =
-        QQmlPropertyCache::property(engine, currentObject, terminal, context, local);
+        QQmlPropertyCache::property(engine, currentObject, terminalString, context, local);
     if (property && !property->isFunction()) {
         object = currentObject;
         core = *property;
-        nameCache = terminal;
+        nameCache = terminalString;
         isNameCached = true;
     }
 }