Use QString::fromLatin1() less to avoid string allocations

QString::fromLatin1 always allocates memory, but there are
cases where we can avoid/reduce allocations or/and reduce
text size, e.g.:

QStringBuilder expressions
Fix: replace QString::fromLatin1 with QL1S

QString::fromLatin1().arg(String) pattern
Fix: replace with QStringBuilder

Overloaded functions with QL1S arg
Fix: replace QString::fromLatin1 with QL1S

In rare cases if there is no overloaded function
with QL1S and we have deal with string literal,
replace QString::fromLatin1 with QStringLiteral.

Change-Id: Iabe1a3cc0830f40ef78a0548afa4368583c31def
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>

1 files changed, 2 insertions, 4 deletions

diff --git a/src/dbus/qdbusinternalfilters.cpp b/src/dbus/qdbusinternalfilters.cpp
index ad6b06da23..03e04bb2f5 100644
--- a/src/dbus/qdbusinternalfilters.cpp
+++ b/src/dbus/qdbusinternalfilters.cpp
@@ -116,8 +116,7 @@ static QString generateSubObjectXml(QObject *object)
     for ( ; it != end; ++it) {
         QString name = (*it)->objectName();
         if (!name.isEmpty() && QDBusUtil::isValidPartOfObjectPath(name))
-            retval += QString::fromLatin1("  <node name=\"%1\"/>\n")
-                      .arg(name);
+            retval += QLatin1String("  <node name=\"") + name + QLatin1String("\"/>\n");
     }
     return retval;
 }
@@ -192,8 +191,7 @@ QString qDBusIntrospectObject(const QDBusConnectionPrivate::ObjectTreeNode &node
             node.children.constEnd();
         for ( ; it != end; ++it)
             if (it->obj || !it->children.isEmpty())
-                xml_data += QString::fromLatin1("  <node name=\"%1\"/>\n")
-                            .arg(it->name);
+                xml_data += QLatin1String("  <node name=\"") + it->name + QLatin1String("\"/>\n");
     }
 
     xml_data += QLatin1String("</node>\n");