diff --git a/plugins/quickopen/projectitemquickopen.cpp b/plugins/quickopen/projectitemquickopen.cpp
index e9acb4846..d1beb727e 100644
--- a/plugins/quickopen/projectitemquickopen.cpp
+++ b/plugins/quickopen/projectitemquickopen.cpp
@@ -1,377 +1,382 @@
 /* This file is part of the KDE libraries
    Copyright (C) 2007 David Nolden <david.nolden.kdevelop@art-master.de>
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License version 2 as published by the Free Software Foundation.
 
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.
 
    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
  */
 
 #include "projectitemquickopen.h"
 #include "debug.h"
 
 #include <language/duchain/topducontext.h>
 #include <language/duchain/duchain.h>
 #include <language/duchain/duchainlock.h>
 #include <language/duchain/declaration.h>
 #include <language/duchain/abstractfunctiondeclaration.h>
 #include <language/duchain/types/structuretype.h>
 #include <language/duchain/duchainutils.h>
 #include <language/duchain/codemodel.h>
 #include <language/interfaces/iquickopen.h>
 #include <language/interfaces/abbreviations.h>
 
 #include <interfaces/iproject.h>
 #include <interfaces/iprojectcontroller.h>
 #include <interfaces/icore.h>
 
 #include <project/projectmodel.h>
 
 #include <KLocalizedString>
 
 using namespace KDevelop;
 
 namespace {
 struct SubstringCache
 {
     explicit SubstringCache(const QString& string = QString())
         : substring(string)
     {
     }
 
     inline int containedIn(const Identifier& id) const
     {
         int index = id.index();
         QHash<int, int>::const_iterator it = cache.constFind(index);
         if (it != cache.constEnd()) {
             return *it;
         }
 
         const QString idStr = id.identifier().str();
 
         int result = idStr.lastIndexOf(substring, -1, Qt::CaseInsensitive);
         if (result < 0 && !idStr.isEmpty() && !substring.isEmpty()) {
             // no match; try abbreviations
             result = matchesAbbreviation(idStr.midRef(0), substring) ? 0 : -1;
         }
 
         //here we shift the values if the matched string is bigger than the substring,
         //so closer matches will appear first
         if (result >= 0) {
             result = result + (idStr.size() - substring.size());
         }
 
         cache[index] = result;
 
         return result;
     }
 
     QString substring;
     mutable QHash<int, int> cache;
 };
 
 struct ClosestMatchToText
 {
     explicit ClosestMatchToText(const QHash<int, int>& _cache)
         : cache(_cache)
     {
     }
 
     /** @brief Calculates the distance to two pre-filtered match items
      *
      *  @param a The CodeModelView witch represents the first item to be tested
      *  @param b The CodeModelView witch represents the second item to be tested
      *
      *  @b
      */
     inline bool operator()(const CodeModelViewItem& a, const CodeModelViewItem& b) const
     {
         const int height_a = cache.value(a.m_id.index(), -1);
         const int height_b = cache.value(b.m_id.index(), -1);
 
         Q_ASSERT(height_a != -1);
         Q_ASSERT(height_b != -1);
 
         if (height_a == height_b) {
             // stable sorting for equal items based on index
             // TODO: fast string-based sorting in such cases?
             return a.m_id.index() < b.m_id.index();
         }
 
         return height_a < height_b;
     }
 private:
     const QHash<int, int>& cache;
 };
 
 Path findProjectForForPath(const IndexedString& path)
 {
     const auto model = ICore::self()->projectController()->projectModel();
     const auto item = model->itemForPath(path);
     return item ? item->project()->path() : Path();
 }
+uint addedItems(const AddedItems& items)
+{
+    uint add = 0;
+    for(auto it = items.constBegin(); it != items.constEnd(); ++it) {
+        add += it.value().count();
+    }
+    return add;
+}
+
 }
 
 ProjectItemDataProvider::ProjectItemDataProvider(KDevelop::IQuickOpen* quickopen)
     : m_quickopen(quickopen)
+    , m_addedItemsCountCache([this]() { return addedItems(m_addedItems); })
 {
 }
 
 void ProjectItemDataProvider::setFilterText(const QString& text)
 {
     m_addedItems.clear();
+    m_addedItemsCountCache.markDirty();
 
     QStringList search(text.split(QStringLiteral("::"), QString::SkipEmptyParts));
     for (int a = 0; a < search.count(); ++a) {
         if (search[a].endsWith(':')) { //Don't get confused while the :: is being typed
             search[a] = search[a].left(search[a].length() - 1);
         }
     }
 
     if (!search.isEmpty() && search.back().endsWith('(')) {
         search.back().chop(1);
     }
 
     if (text.isEmpty() || search.isEmpty()) {
         m_filteredItems = m_currentItems;
         return;
     }
 
     KDevVarLengthArray<SubstringCache, 5> cache;
     foreach (const QString& searchPart, search) {
         cache.append(SubstringCache(searchPart));
     }
 
     if (!text.startsWith(m_currentFilter)) {
         m_filteredItems = m_currentItems;
     }
 
     m_currentFilter = text;
 
     QVector<CodeModelViewItem> oldFiltered = m_filteredItems;
     QHash<int, int> heights;
 
     m_filteredItems.clear();
 
     foreach (const CodeModelViewItem& item, oldFiltered) {
         const QualifiedIdentifier& currentId = item.m_id;
 
         int last_pos = currentId.count() - 1;
         int current_height = 0;
         int distance = 0;
 
         //iter over each search item from last to first
         //this makes easier to calculate the distance based on where we hit the result or nothing
         //Iterating from the last item to the first is more efficient, as we want to match the
         //class/function name, which is the last item on the search fields and on the identifier.
         for (int b = search.count() - 1; b >= 0; --b) {
             //iter over each id for the current identifier, from last to first
             for (; last_pos >= 0; --last_pos, distance++) {
                 // the more distant we are from the class definition, the less priority it will have
                 current_height += distance * 10000;
                 int result;
                 //if the current search item is contained on the current identifier
                 if ((result = cache[b].containedIn(currentId.at(last_pos))) >= 0) {
                     //when we find a hit, whe add the distance to the searched word.
                     //so the closest item will be displayed first
                     current_height += result;
 
                     if (b == 0) {
                         heights[currentId.index()] = current_height;
                         m_filteredItems << item;
                     }
                     break;
                 }
             }
         }
     }
 
     //then, for the last part, we use the already built cache to sort the items according with their distance
     std::sort(m_filteredItems.begin(), m_filteredItems.end(), ClosestMatchToText(heights));
 }
 
 QList<KDevelop::QuickOpenDataPointer> ProjectItemDataProvider::data(uint start, uint end) const
 {
     QList<KDevelop::QuickOpenDataPointer> ret;
     for (uint a = start; a < end; ++a) {
         ret << data(a);
     }
 
     return ret;
 }
 
 KDevelop::QuickOpenDataPointer ProjectItemDataProvider::data(uint pos) const
 {
     //Check whether this position falls into an appended item-list, else apply the offset
     uint filteredItemOffset = 0;
     for (AddedItems::const_iterator it = m_addedItems.constBegin(); it != m_addedItems.constEnd(); ++it) {
         int offsetInAppended = pos - (it.key() + 1);
         if (offsetInAppended >= 0 && offsetInAppended < it.value().count()) {
             return it.value()[offsetInAppended];
         }
         if (it.key() >= pos) {
             break;
         }
         filteredItemOffset += it.value().count();
     }
 
     const uint a = pos - filteredItemOffset;
     if (a > ( uint )m_filteredItems.size()) {
         return KDevelop::QuickOpenDataPointer();
     }
 
     const auto& filteredItem = m_filteredItems[a];
 
     QList<KDevelop::QuickOpenDataPointer> ret;
     KDevelop::DUChainReadLocker lock(DUChain::lock());
     TopDUContext* ctx = DUChainUtils::standardContextForUrl(filteredItem.m_file.toUrl());
     if (ctx) {
         QList<Declaration*> decls = ctx->findDeclarations(filteredItem.m_id, CursorInRevision::invalid(), AbstractType::Ptr(), nullptr, DUContext::DirectQualifiedLookup);
 
         //Filter out forward-declarations or duplicate imported declarations
         foreach (Declaration* decl, decls) {
             bool filter = false;
             if (decls.size() > 1 && decl->isForwardDeclaration()) {
                 filter = true;
             } else if (decl->url() != filteredItem.m_file && m_files.contains(decl->url())) {
                 filter = true;
             }
             if (filter) {
                 decls.removeOne(decl);
             }
         }
 
         foreach (Declaration* decl, decls) {
             DUChainItem item;
             item.m_item = decl;
             item.m_text = decl->qualifiedIdentifier().toString();
             item.m_projectPath = findProjectForForPath(filteredItem.m_file);
             ret << QuickOpenDataPointer(new DUChainItemData(item));
         }
 
         if (decls.isEmpty()) {
             DUChainItem item;
             item.m_text = filteredItem.m_id.toString();
             item.m_projectPath = findProjectForForPath(filteredItem.m_file);
             ret << QuickOpenDataPointer(new DUChainItemData(item));
         }
     } else {
         qCDebug(PLUGIN_QUICKOPEN) << "Could not find standard-context";
     }
 
     if (!ret.isEmpty()) {
         QList<KDevelop::QuickOpenDataPointer> append = ret.mid(1);
         if (!append.isEmpty()) {
+            m_addedItemsCountCache.markDirty();
+
             AddedItems addMap;
             for (AddedItems::iterator it = m_addedItems.begin(); it != m_addedItems.end(); ) {
                 if (it.key() == pos) { //There already is appended data stored, nothing to do
                     return ret.first();
                 } else if (it.key() > pos) {
                     addMap[it.key() + append.count()] = it.value();
                     it = m_addedItems.erase(it);
                 } else {
                     ++it;
                 }
             }
 
             m_addedItems.insert(pos, append);
 
             for (AddedItems::const_iterator it = addMap.constBegin(); it != addMap.constEnd(); ++it) {
                 m_addedItems.insert(it.key(), it.value());
             }
         }
         return ret.first();
     } else {
         return KDevelop::QuickOpenDataPointer();
     }
 }
 
 void ProjectItemDataProvider::reset()
 {
     m_files = m_quickopen->fileSet();
     m_currentItems.clear();
     m_addedItems.clear();
+    m_addedItemsCountCache.markDirty();
 
     KDevelop::DUChainReadLocker lock(DUChain::lock());
     foreach (const IndexedString& u, m_files) {
         uint count;
         const KDevelop::CodeModelItem* items;
         CodeModel::self().items(u, count, items);
 
         for (uint a = 0; a < count; ++a) {
             if (!items[a].id.isValid() || items[a].kind & CodeModelItem::ForwardDeclaration) {
                 continue;
             }
             if (((m_itemTypes & Classes) && (items[a].kind & CodeModelItem::Class)) ||
                 ((m_itemTypes & Functions) && (items[a].kind & CodeModelItem::Function))) {
                 QualifiedIdentifier id = items[a].id.identifier();
 
                 if (id.isEmpty() || id.at(0).identifier().isEmpty()) {
                     // id.isEmpty() not always hit when .toString() is actually empty...
                     // anyhow, this makes sure that we don't show duchain items without
                     // any name that could be searched for. This happens e.g. in the c++
                     // plugin for anonymous structs or sometimes for declarations in macro
                     // expressions
                     continue;
                 }
                 m_currentItems << CodeModelViewItem(u, id);
             }
         }
     }
 
     m_filteredItems = m_currentItems;
     m_currentFilter.clear();
 }
 
-uint addedItems(const AddedItems& items)
-{
-    uint add = 0;
-    for (AddedItems::const_iterator it = items.constBegin(); it != items.constEnd(); ++it) {
-        add += it.value().count();
-    }
-
-    return add;
-}
 
 uint ProjectItemDataProvider::itemCount() const
 {
-    return m_filteredItems.count() + addedItems(m_addedItems);
+    return m_filteredItems.count() + m_addedItemsCountCache.cachedResult();
 }
 
 uint ProjectItemDataProvider::unfilteredItemCount() const
 {
-    return m_currentItems.count() + addedItems(m_addedItems);
+    return m_currentItems.count() + m_addedItemsCountCache.cachedResult();
 }
 
 QStringList ProjectItemDataProvider::supportedItemTypes()
 {
     QStringList ret;
     ret << i18n("Classes");
     ret << i18n("Functions");
     return ret;
 }
 
 void ProjectItemDataProvider::enableData(const QStringList& items, const QStringList& scopes)
 {
     //FIXME: property support different scopes
     if (scopes.contains(i18n("Project"))) {
         m_itemTypes = NoItems;
         if (items.contains(i18n("Classes"))) {
             m_itemTypes = ( ItemTypes )(m_itemTypes | Classes);
         }
         if (items.contains(i18n("Functions"))) {
             m_itemTypes = ( ItemTypes )(m_itemTypes | Functions);
         }
     } else {
         m_itemTypes = NoItems;
     }
 }
diff --git a/plugins/quickopen/projectitemquickopen.h b/plugins/quickopen/projectitemquickopen.h
index 2a22d5831..a9762944d 100644
--- a/plugins/quickopen/projectitemquickopen.h
+++ b/plugins/quickopen/projectitemquickopen.h
@@ -1,85 +1,125 @@
 /* This file is part of the KDE libraries
    Copyright (C) 2007 David Nolden <david.nolden.kdevelop@art-master.de>
 
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License version 2 as published by the Free Software Foundation.
 
    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Library General Public License for more details.
 
    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
  */
 #ifndef PROJECT_ITEM_QUICKOPEN
 #define PROJECT_ITEM_QUICKOPEN
 
 #include "duchainitemquickopen.h"
 
 #include <serialization/indexedstring.h>
 #include <language/duchain/identifier.h>
 
+#include <functional>
+#include <type_traits>
+
+template <typename Type>
+class ResultCache
+{
+public:
+    ResultCache(std::function<Type()> func)
+        : m_func(func)
+    {
+    }
+
+    /// Mark this cache dirty. A call to cachedResult() will need to refill the cache
+    inline void markDirty() const
+    {
+        m_isDirty = true;
+    }
+
+    /**
+     * If marked dirty, calls @p func and stores return value of @p func
+     *
+     * @return Cached result of @p func
+     */
+    inline Type cachedResult() const
+    {
+        if (m_isDirty) {
+            m_result = m_func();
+            m_isDirty = false;
+        }
+        return m_result;
+    }
+private:
+    std::function<Type()> m_func;
+
+    mutable Type m_result;
+    mutable bool m_isDirty = false;
+};
+
 struct CodeModelViewItem
 {
     CodeModelViewItem()
     {
     }
     CodeModelViewItem(const KDevelop::IndexedString& file, const KDevelop::QualifiedIdentifier& id)
         : m_file(file)
         , m_id(id)
     {
     }
     KDevelop::IndexedString m_file;
     KDevelop::QualifiedIdentifier m_id;
 };
 
 Q_DECLARE_TYPEINFO(CodeModelViewItem, Q_MOVABLE_TYPE);
 
 typedef QMap<uint, QList<KDevelop::QuickOpenDataPointer> > AddedItems;
 
 class ProjectItemDataProvider
     : public KDevelop::QuickOpenDataProviderBase
 {
     Q_OBJECT
 public:
     enum ItemTypes {
         NoItems = 0,
         Classes = 1,
         Functions = 2,
         AllItemTypes = Classes + Functions
     };
 
     explicit ProjectItemDataProvider(KDevelop::IQuickOpen* quickopen);
 
     void enableData(const QStringList& items, const QStringList& scopes) override;
 
     void setFilterText(const QString& text) override;
 
     virtual QList<KDevelop::QuickOpenDataPointer> data(uint start, uint end) const;
 
     void reset() override;
 
     uint itemCount() const override;
     uint unfilteredItemCount() const override;
 
     static QStringList supportedItemTypes();
 private:
     KDevelop::QuickOpenDataPointer data(uint pos) const override;
 
     ItemTypes m_itemTypes;
     KDevelop::IQuickOpen* m_quickopen;
     QSet<KDevelop::IndexedString> m_files;
     QVector<CodeModelViewItem> m_currentItems;
     QString m_currentFilter;
     QVector<CodeModelViewItem> m_filteredItems;
+
     //Maps positions to the additional items behind those positions
     //Here additional inserted items are stored, that are not represented in m_filteredItems.
     //This is needed at least to also show overloaded function declarations
     mutable AddedItems m_addedItems;
+    ResultCache<uint> m_addedItemsCountCache;
 };
 
 #endif