QStringBuilder: reduce the size of the generated code

A simple concatenation of 2 string does not benefit from the
QStringBuilder trick, yet, this would produce more code with
QT_USE_FAST_OPERATOR_PLUS

This commit specialize the QStringBuilder with two QString so it
produce the same code as without it.

Reviewed-by: joao
Reviewed-by: hjk

1 files changed, 14 insertions, 0 deletions

diff --git a/src/corelib/tools/qstringbuilder.h b/src/corelib/tools/qstringbuilder.h
index 74661c2..4ff1b36 100644
--- a/src/corelib/tools/qstringbuilder.h
+++ b/src/corelib/tools/qstringbuilder.h
@@ -117,6 +117,20 @@ public:
 };
 
 
+template <>
+class QStringBuilder <QString, QString>
+{
+    public:
+        QStringBuilder(const QString &a_, const QString &b_) : a(a_), b(b_) {}
+
+        operator QString() const
+        { QString r(a); r += b; return r; }
+        QByteArray toLatin1() const { return QString(*this).toLatin1(); }
+
+        const QString &a;
+        const QString &b;
+};
+
 template <> struct QConcatenable<char> : private QAbstractConcatenable
 {
     typedef char type;