Use QStringBuilder more

Reduce allocations.

Change-Id: I8b8a0d0360e618c65894f1f7c12476b41a1dbc5d
Reviewed-by: Shawn Rutledge <shawn.rutledge@qt.io>

8 files changed, 29 insertions, 42 deletions

diff --git a/src/quick/accessible/qaccessiblequickitem.cpp b/src/quick/accessible/qaccessiblequickitem.cpp
index acea958e20..58eab508ad 100644
--- a/src/quick/accessible/qaccessiblequickitem.cpp
+++ b/src/quick/accessible/qaccessiblequickitem.cpp
@@ -273,8 +273,8 @@ void QAccessibleQuickItem::doAction(const QString &actionName)
         return;
     // Look for and call the accessible[actionName]Action() function on the item.
     // This allows for overriding the default action handling.
-    const QByteArray functionName = QByteArrayLiteral("accessible") + actionName.toLatin1() + QByteArrayLiteral("Action");
-    if (object()->metaObject()->indexOfMethod(QByteArray(functionName + QByteArrayLiteral("()"))) != -1) {
+    const QByteArray functionName = "accessible" + actionName.toLatin1() + "Action";
+    if (object()->metaObject()->indexOfMethod(QByteArray(functionName + "()")) != -1) {
         QMetaObject::invokeMethod(object(), functionName);
         return;
     }
diff --git a/src/quick/items/qquickopenglshadereffect.cpp b/src/quick/items/qquickopenglshadereffect.cpp
index b974641cca..42fcee3c0d 100644
--- a/src/quick/items/qquickopenglshadereffect.cpp
+++ b/src/quick/items/qquickopenglshadereffect.cpp
@@ -284,14 +284,14 @@ void QQuickOpenGLShaderEffectCommon::updateParseLog(bool ignoreAttributes)
     parseLog.clear();
     if (!ignoreAttributes) {
         if (!attributes.contains(qtPositionAttributeName())) {
-            parseLog += QLatin1String("Warning: Missing reference to \'");
-            parseLog += QLatin1String(qtPositionAttributeName());
-            parseLog += QLatin1String("\'.\n");
+            parseLog += QLatin1String("Warning: Missing reference to \'")
+                        + QLatin1String(qtPositionAttributeName())
+                        + QLatin1String("\'.\n");
         }
         if (!attributes.contains(qtTexCoordAttributeName())) {
-            parseLog += QLatin1String("Warning: Missing reference to \'");
-            parseLog += QLatin1String(qtTexCoordAttributeName());
-            parseLog += QLatin1String("\'.\n");
+            parseLog += QLatin1String("Warning: Missing reference to \'")
+                        + QLatin1String(qtTexCoordAttributeName())
+                        + QLatin1String("\'.\n");
         }
     }
     bool respectsMatrix = false;
@@ -918,9 +918,7 @@ QSGNode *QQuickOpenGLShaderEffect::handleUpdatePaintNode(QSGNode *oldNode, QQuic
         if (!mesh->validateAttributes(m_common.attributes, &posIndex)) {
             QString log = mesh->log();
             if (!log.isNull()) {
-                m_log = parseLog();
-                m_log += QLatin1String("*** Mesh ***\n");
-                m_log += log;
+                m_log = parseLog() + QLatin1String("*** Mesh ***\n") + log;
                 m_status = QQuickShaderEffect::Error;
                 emit m_item->logChanged();
                 emit m_item->statusChanged();
diff --git a/src/quick/items/qquickopenglshadereffectnode.cpp b/src/quick/items/qquickopenglshadereffectnode.cpp
index 02b76b2dbc..e01ecc59e3 100644
--- a/src/quick/items/qquickopenglshadereffectnode.cpp
+++ b/src/quick/items/qquickopenglshadereffectnode.cpp
@@ -261,13 +261,11 @@ void QQuickCustomMaterialShader::compile()
     m_log.clear();
     m_compiled = true;
     if (!program()->addShaderFromSourceCode(QOpenGLShader::Vertex, vertexShader())) {
-        m_log += QLatin1String("*** Vertex shader ***\n");
-        m_log += program()->log();
+        m_log += QLatin1String("*** Vertex shader ***\n") + program()->log();
         m_compiled = false;
     }
     if (!program()->addShaderFromSourceCode(QOpenGLShader::Fragment, fragmentShader())) {
-        m_log += QLatin1String("*** Fragment shader ***\n");
-        m_log += program()->log();
+        m_log += QLatin1String("*** Fragment shader ***\n") + program()->log();
         m_compiled = false;
     }
 
diff --git a/src/quick/items/qquickshadereffectmesh.cpp b/src/quick/items/qquickshadereffectmesh.cpp
index 8616bf8022..c1499579e6 100644
--- a/src/quick/items/qquickshadereffectmesh.cpp
+++ b/src/quick/items/qquickshadereffectmesh.cpp
@@ -95,9 +95,8 @@ bool QQuickGridMesh::validateAttributes(const QVector<QByteArray> &attributes, i
         return false;
     case 1:
         if (positionIndex != 0) {
-            m_log = QLatin1String("Error: Missing \'");
-            m_log += QLatin1String(qtPositionAttributeName());
-            m_log += QLatin1String("\' attribute.\n");
+            m_log = QLatin1String("Error: Missing \'") + QLatin1String(qtPositionAttributeName())
+                    + QLatin1String("\' attribute.\n");
             return false;
         }
         break;
@@ -105,14 +104,12 @@ bool QQuickGridMesh::validateAttributes(const QVector<QByteArray> &attributes, i
         if (positionIndex == -1 || texCoordIndex == -1) {
             m_log.clear();
             if (positionIndex == -1) {
-                m_log = QLatin1String("Error: Missing \'");
-                m_log += QLatin1String(qtPositionAttributeName());
-                m_log += QLatin1String("\' attribute.\n");
+                m_log = QLatin1String("Error: Missing \'") + QLatin1String(qtPositionAttributeName())
+                        + QLatin1String("\' attribute.\n");
             }
             if (texCoordIndex == -1) {
-                m_log += QLatin1String("Error: Missing \'");
-                m_log += QLatin1String(qtTexCoordAttributeName());
-                m_log += QLatin1String("\' attribute.\n");
+                m_log += QLatin1String("Error: Missing \'") + QLatin1String(qtTexCoordAttributeName())
+                         + QLatin1String("\' attribute.\n");
             }
             return false;
         }
diff --git a/src/quick/scenegraph/coreapi/qsgshaderrewriter.cpp b/src/quick/scenegraph/coreapi/qsgshaderrewriter.cpp
index 3a35632d5c..96b489cd24 100644
--- a/src/quick/scenegraph/coreapi/qsgshaderrewriter.cpp
+++ b/src/quick/scenegraph/coreapi/qsgshaderrewriter.cpp
@@ -214,9 +214,9 @@ QByteArray qsgShaderRewriter_insertZAttributes(const char *input, QSurfaceFormat
         case Tokenizer::Token_CloseBrace:
             braceDepth--;
             if (braceDepth == 0) {
-                result += QByteArray::fromRawData(voidPos, tok.pos - 1 - voidPos);
-                result += QByteArrayLiteral("    gl_Position.z = (gl_Position.z * _qt_zRange + _qt_order) * gl_Position.w;\n");
-                result += QByteArray(tok.pos - 1);
+                result += QByteArray::fromRawData(voidPos, tok.pos - 1 - voidPos)
+                        + "    gl_Position.z = (gl_Position.z * _qt_zRange + _qt_order) * gl_Position.w;\n"
+                        + QByteArray(tok.pos - 1);
                 return result;
             }
             break;
diff --git a/src/quick/scenegraph/qsgdefaultdistancefieldglyphcache_p.h b/src/quick/scenegraph/qsgdefaultdistancefieldglyphcache_p.h
index eeea104e91..9ad99e5c54 100644
--- a/src/quick/scenegraph/qsgdefaultdistancefieldglyphcache_p.h
+++ b/src/quick/scenegraph/qsgdefaultdistancefieldglyphcache_p.h
@@ -116,9 +116,8 @@ private:
     {
         m_blitProgram = new QOpenGLShaderProgram;
         {
-            QString source;
-            source.append(QLatin1String(qopenglslMainWithTexCoordsVertexShader));
-            source.append(QLatin1String(qopenglslUntransformedPositionVertexShader));
+            const QString source = QLatin1String(qopenglslMainWithTexCoordsVertexShader)
+                                 + QLatin1String(qopenglslUntransformedPositionVertexShader);
 
             QOpenGLShader *vertexShader = new QOpenGLShader(QOpenGLShader::Vertex, m_blitProgram);
             vertexShader->compileSourceCode(source);
@@ -126,9 +125,8 @@ private:
             m_blitProgram->addShader(vertexShader);
         }
         {
-            QString source;
-            source.append(QLatin1String(qopenglslMainFragmentShader));
-            source.append(QLatin1String(qopenglslImageSrcFragmentShader));
+            const QString source = QLatin1String(qopenglslMainFragmentShader)
+                                 + QLatin1String(qopenglslImageSrcFragmentShader);
 
             QOpenGLShader *fragmentShader = new QOpenGLShader(QOpenGLShader::Fragment, m_blitProgram);
             fragmentShader->compileSourceCode(source);
diff --git a/src/quick/scenegraph/util/qsgshadersourcebuilder.cpp b/src/quick/scenegraph/util/qsgshadersourcebuilder.cpp
index caa296451e..25af1997a8 100644
--- a/src/quick/scenegraph/util/qsgshadersourcebuilder.cpp
+++ b/src/quick/scenegraph/util/qsgshadersourcebuilder.cpp
@@ -310,13 +310,10 @@ void QSGShaderSourceBuilder::addDefinition(const QByteArray &definition)
     const char *insertionPos = extensionPos ? extensionPos : (versionPos ? versionPos : input);
 
     // Construct a new shader string, inserting the definition
-    QByteArray newSource;
-    newSource.reserve(m_source.size() + definition.size() + 9);
-    newSource += QByteArray::fromRawData(input, insertionPos - input);
-    newSource += QByteArrayLiteral("#define ") + definition + QByteArrayLiteral("\n");
-    newSource += QByteArray::fromRawData(insertionPos, m_source.size() - (insertionPos - input));
-
-    m_source = newSource;
+    QByteArray newSource = QByteArray::fromRawData(input, insertionPos - input)
+            + "#define " + definition + '\n'
+            + QByteArray::fromRawData(insertionPos, m_source.size() - (insertionPos - input));
+    m_source = std::move(newSource);
 }
 
 void QSGShaderSourceBuilder::removeVersion()
diff --git a/src/quick/util/qquickstyledtext.cpp b/src/quick/util/qquickstyledtext.cpp
index 4139c87eda..ae8719341d 100644
--- a/src/quick/util/qquickstyledtext.cpp
+++ b/src/quick/util/qquickstyledtext.cpp
@@ -721,8 +721,7 @@ void QQuickStyledTextPrivate::parseImageAttributes(const QChar *&ch, const QStri
     QString padding(qFloor(imgWidth / spaceWidth), QChar::Nbsp);
     if (!trailingSpace)
         textOut += QLatin1Char(' ');
-    textOut += padding;
-    textOut += QLatin1Char(' ');
+    textOut += padding + QLatin1Char(' ');
 }
 
 QPair<QStringRef,QStringRef> QQuickStyledTextPrivate::parseAttribute(const QChar *&ch, const QString &textIn)