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diff --git a/src/libs/clangsupport/filepathcache.h b/src/libs/clangsupport/filepathcache.h
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+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+****************************************************************************/
+
+#pragma once
+
+#include "filepathexceptions.h"
+#include "filepathid.h"
+#include "filepath.h"
+#include "stringcache.h"
+
+#include <utils/smallstringview.h>
+
+#include <algorithm>
+
+namespace ClangBackEnd {
+
+class FilePathCacheBase
+{
+public:
+    static
+    std::ptrdiff_t lastSlashIndex(Utils::SmallStringView filePath)
+    {
+        auto foundReverse = std::find(filePath.rbegin(), filePath.rend(), '/');
+        auto found = foundReverse.base();
+        --found;
+
+        return std::distance(filePath.begin(), found);
+    }
+
+    static
+    Utils::SmallStringView directoryPath(Utils::SmallStringView filePath, std::ptrdiff_t slashIndex)
+    {
+        return {filePath.data(), std::size_t(std::max(std::ptrdiff_t(0), slashIndex))};
+    }
+
+    static
+    Utils::SmallStringView fileName(Utils::SmallStringView filePath, std::ptrdiff_t slashIndex)
+    {
+        return {filePath.data() + slashIndex + 1, filePath.size() - std::size_t(slashIndex) - 1};
+    }
+};
+
+template <typename FilePathStorage>
+class FilePathCache final : private FilePathCacheBase
+{
+    using DirectoryPathCache = StringCache<Utils::PathString,
+                                           int,
+                                           std::mutex,
+                                           decltype(&Utils::reverseCompare),
+                                           Utils::reverseCompare>;
+    using FileNameCache = StringCache<Utils::SmallString,
+                                      int,
+                                      std::mutex,
+                                      decltype(&Utils::compare),
+                                      Utils::compare>;
+public:
+    FilePathCache(FilePathStorage &filePathStorage)
+        : m_filePathStorage(filePathStorage)
+    {}
+
+    FilePathId filePathId(Utils::SmallStringView filePath) const
+    {
+        std::ptrdiff_t slashIndex = lastSlashIndex(filePath);
+
+        Utils::SmallStringView directoryPath = this->directoryPath(filePath, slashIndex);
+        int directoryId = m_directyPathCache.stringId(directoryPath,
+                                                      [&] (const Utils::SmallStringView) {
+            return m_filePathStorage.fetchDirectoryId(directoryPath);
+        });
+
+        Utils::SmallStringView fileName = this->fileName(filePath, slashIndex);
+
+        int fileNameId = m_fileNameCache.stringId(fileName,
+                                                  [&] (const Utils::SmallStringView) {
+            return m_filePathStorage.fetchSourceId(directoryId, fileName);
+        });
+
+        return {directoryId, fileNameId};
+    }
+
+    FilePath filePath(FilePathId filePathId) const
+    {
+        if (Q_UNLIKELY(!filePathId.isValid()))
+            throw NoFilePathForInvalidFilePathId();
+
+        auto fetchFilePath = [&] (int id) { return m_filePathStorage.fetchDirectoryPath(id); };
+
+        Utils::PathString directoryPath = m_directyPathCache.string(filePathId.directoryId,
+                                                                    fetchFilePath);
+
+
+        auto fetchSoureName = [&] (int id) { return m_filePathStorage.fetchSourceName(id); };
+
+        Utils::SmallString fileName = m_fileNameCache.string(filePathId.fileNameId,
+                                                             fetchSoureName);
+
+        return {directoryPath, fileName};
+    }
+
+private:
+    mutable DirectoryPathCache m_directyPathCache;
+    mutable FileNameCache m_fileNameCache;
+    FilePathStorage &m_filePathStorage;
+};
+
+} // namespace ClangBackEnd