Optimize CppCodeMarker::addMarkUp further

This avoids a couple of more string/memory
allocations, giving another 5% speed gain
for qdoc --prepare.

Change-Id: I455f615bb4388d883dca5a8cd31bf50629db23e0
Reviewed-by: Martin Smith <martin.smith@digia.com>

3 files changed, 12 insertions, 15 deletions

diff --git a/src/tools/qdoc/codemarker.cpp b/src/tools/qdoc/codemarker.cpp
index e00ebef2db..458799fc27 100644
--- a/src/tools/qdoc/codemarker.cpp
+++ b/src/tools/qdoc/codemarker.cpp
@@ -194,22 +194,20 @@ QString CodeMarker::protect(const QString& str)
     return marked;
 }
 
-QString CodeMarker::protect(const QStringRef& str)
+void CodeMarker::appendProtectedString(QString *output, const QStringRef &str)
 {
     int n = str.length();
-    QString marked;
-    marked.reserve(n * 2 + 30);
+    output->reserve(output->size() + n * 2 + 30);
     const QChar *data = str.constData();
     for (int i = 0; i != n; ++i) {
         switch (data[i].unicode()) {
-        case '&': marked += samp;  break;
-        case '<': marked += slt;   break;
-        case '>': marked += sgt;   break;
-        case '"': marked += squot; break;
-        default : marked += data[i];
+        case '&': *output += samp;  break;
+        case '<': *output += slt;   break;
+        case '>': *output += sgt;   break;
+        case '"': *output += squot; break;
+        default : *output += data[i];
         }
     }
-    return marked;
 }
 
 QString CodeMarker::typified(const QString &string)
diff --git a/src/tools/qdoc/codemarker.h b/src/tools/qdoc/codemarker.h
index e407e0ac3f..31a9f3a254 100644
--- a/src/tools/qdoc/codemarker.h
+++ b/src/tools/qdoc/codemarker.h
@@ -163,8 +163,8 @@ public:
 
 protected:
     virtual QString sortName(const Node *node, const QString* name = 0);
-    QString protect(const QString &string);
-    QString protect(const QStringRef &string);
+    static QString protect(const QString &string);
+    static void appendProtectedString(QString *output, const QStringRef &str);
     QString taggedNode(const Node* node);
     QString taggedQmlNode(const Node* node);
     QString linkTag(const Node *node, const QString& body);
diff --git a/src/tools/qdoc/cppcodemarker.cpp b/src/tools/qdoc/cppcodemarker.cpp
index 6060339762..868b249290 100644
--- a/src/tools/qdoc/cppcodemarker.cpp
+++ b/src/tools/qdoc/cppcodemarker.cpp
@@ -929,8 +929,7 @@ QString CppCodeMarker::addMarkUp(const QString &in,
             } else if (keywords.contains(ident)) {
                 tag = QStringLiteral("keyword");
             } else if (braceDepth == 0 && parenDepth == 0) {
-                if (QString(code.unicode() + i - 1, code.length() - (i - 1))
-                        .indexOf(findFunctionRegExp) == 0)
+                if (code.indexOf(findFunctionRegExp, i - 1) == i - 1)
                     tag = QStringLiteral("func");
                 target = true;
             }
@@ -1083,7 +1082,7 @@ QString CppCodeMarker::addMarkUp(const QString &in,
             out += QStringLiteral(">");
         }
 
-        out += protect(text);
+        appendProtectedString(&out, text);
 
         if (!tag.isEmpty()) {
             out += QStringLiteral("</@");
@@ -1093,7 +1092,7 @@ QString CppCodeMarker::addMarkUp(const QString &in,
     }
 
     if (start < code.length()) {
-        out += protect(code.midRef(start));
+        appendProtectedString(&out, code.midRef(start));
     }
 
     return out;