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diff --git a/sc/inc/recursionhelper.hxx b/sc/inc/recursionhelper.hxx
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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#pragma once
+
+#include "formularesult.hxx"
+
+#include <list>
+#include <vector>
+#include <stack>
+#include <o3tl/sorted_vector.hxx>
+
+class ScFormulaCell;
+
+struct ScFormulaRecursionEntry
+{
+    ScFormulaCell*  pCell;
+    bool            bOldRunning;
+    ScFormulaResult aPreviousResult;
+    ScFormulaRecursionEntry(
+        ScFormulaCell* p, bool bR, const ScFormulaResult & rRes ) :
+        pCell(p), bOldRunning(bR), aPreviousResult( rRes)
+    {
+    }
+};
+
+typedef ::std::list< ScFormulaRecursionEntry > ScFormulaRecursionList;
+
+class ScRecursionHelper
+{
+    typedef ::std::stack< ScFormulaCell* >  ScRecursionInIterationStack;
+    ScFormulaRecursionList              aRecursionFormulas;
+    ScFormulaRecursionList::iterator    aInsertPos;
+    ScFormulaRecursionList::iterator    aLastIterationStart;
+    ScRecursionInIterationStack         aRecursionInIterationStack;
+    std::vector< ScFormulaCell* >       aFGList;
+    // Flag list corresponding to aFGList to indicate whether each formula-group
+    // is in a dependency evaluation mode or not.
+    std::vector< bool >                 aInDependencyEvalMode;
+    sal_uInt16                              nRecursionCount;
+    sal_uInt16                              nIteration;
+    // Count of ScFormulaCell::CheckComputeDependencies in current call-stack.
+    sal_uInt16                              nDependencyComputationLevel;
+    bool                                bInRecursionReturn;
+    bool                                bDoingRecursion;
+    bool                                bInIterationReturn;
+    bool                                bConverging;
+    bool                                bGroupsIndependent;
+    bool                                bAbortingDependencyComputation;
+    std::vector< ScFormulaCell* >       aTemporaryGroupCells;
+    o3tl::sorted_vector< ScFormulaCellGroup* >* pFGSet;
+
+    void Init();
+    void ResetIteration();
+
+public:
+
+    ScRecursionHelper();
+    sal_uInt16  GetRecursionCount() const       { return nRecursionCount; }
+    void    IncRecursionCount()             { ++nRecursionCount; }
+    void    DecRecursionCount()             { --nRecursionCount; }
+    sal_uInt16 GetDepComputeLevel() const   { return nDependencyComputationLevel; }
+    void    IncDepComputeLevel();
+    void    DecDepComputeLevel();
+    /// A pure recursion return, no iteration.
+    bool    IsInRecursionReturn() const     { return bInRecursionReturn &&
+        !bInIterationReturn; }
+    void SetInRecursionReturn( bool b );
+    bool    IsDoingRecursion() const        { return bDoingRecursion; }
+    void    SetDoingRecursion( bool b )     { bDoingRecursion = b; }
+
+    void Insert( ScFormulaCell* p, bool bOldRunning, const ScFormulaResult & rRes );
+
+    bool    IsInIterationReturn() const     { return bInIterationReturn; }
+    void SetInIterationReturn( bool b );
+    bool    IsDoingIteration() const        { return nIteration > 0; }
+    sal_uInt16  GetIteration() const            { return nIteration; }
+    bool &  GetConvergingReference()        { return bConverging; }
+    void StartIteration();
+    void ResumeIteration();
+    void IncIteration();
+    void EndIteration();
+
+    const ScFormulaRecursionList::iterator& GetLastIterationStart() const { return aLastIterationStart; }
+    ScFormulaRecursionList::iterator GetIterationStart();
+    ScFormulaRecursionList::iterator GetIterationEnd();
+    /** Any return, recursion or iteration, iteration is always coupled with
+        recursion. */
+    bool    IsInReturn() const              { return bInRecursionReturn; }
+    const ScFormulaRecursionList&   GetList() const { return aRecursionFormulas; }
+    ScFormulaRecursionList&         GetList()       { return aRecursionFormulas; }
+    ScRecursionInIterationStack&    GetRecursionInIterationStack()  { return aRecursionInIterationStack; }
+
+    void Clear();
+
+    /** Detects a simple cycle involving formula-groups and singleton formula-cells. */
+    bool PushFormulaGroup(ScFormulaCell* pCell);
+    void PopFormulaGroup();
+    bool AnyCycleMemberInDependencyEvalMode(const ScFormulaCell* pCell);
+    bool AnyParentFGInCycle();
+    void SetFormulaGroupDepEvalMode(bool bSet);
+    // When dependency computation detects a cycle, it may not compute proper cell values.
+    // This sets a flag that ScFormulaCell will use to avoid setting those new values
+    // and resetting the dirty flag, until the dependency computation bails out.
+    void AbortDependencyComputation();
+    bool IsAbortingDependencyComputation() const { return bAbortingDependencyComputation; }
+
+    void AddTemporaryGroupCell(ScFormulaCell* cell);
+    void CleanTemporaryGroupCells();
+
+    void SetFormulaGroupSet(o3tl::sorted_vector<ScFormulaCellGroup*>* pSet) { pFGSet = pSet; }
+    bool HasFormulaGroupSet() const { return pFGSet != nullptr; }
+    bool CheckFGIndependence(ScFormulaCellGroup* pFG);
+    void SetGroupsIndependent(bool bSet) { bGroupsIndependent = bSet; }
+    bool AreGroupsIndependent() { return bGroupsIndependent; }
+};
+
+/** A class to wrap ScRecursionHelper::PushFormulaGroup(),
+    ScRecursionHelper::PopFormulaGroup() and make these calls
+    exception safe. */
+class ScFormulaGroupCycleCheckGuard
+{
+    ScRecursionHelper& mrRecHelper;
+    bool mbShouldPop;
+public:
+    ScFormulaGroupCycleCheckGuard() = delete;
+    ScFormulaGroupCycleCheckGuard(ScRecursionHelper& rRecursionHelper, ScFormulaCell* pCell);
+    ~ScFormulaGroupCycleCheckGuard();
+
+};
+
+class ScFormulaGroupDependencyComputeGuard
+{
+    ScRecursionHelper& mrRecHelper;
+public:
+    ScFormulaGroupDependencyComputeGuard() = delete;
+    ScFormulaGroupDependencyComputeGuard(ScRecursionHelper& rRecursionHelper);
+    ~ScFormulaGroupDependencyComputeGuard();
+};
+
+class ScCheckIndependentFGGuard
+{
+    ScRecursionHelper& mrRecHelper;
+    bool mbUsedFGSet;
+public:
+    ScCheckIndependentFGGuard() = delete;
+    ScCheckIndependentFGGuard(ScRecursionHelper& rRecursionHelper,
+                              o3tl::sorted_vector<ScFormulaCellGroup*>* pSet);
+    ~ScCheckIndependentFGGuard();
+
+    bool AreGroupsIndependent();
+};
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */