tdf#100894 freeze when editing calc file with bazillions of cond formatting

This does not fix the root cause of this problem, which is simply that
the document has a bazillion style sheets. Either the program which
exported this document is broken, or our importer is not correctly de-
duplicating the imported stylesheets.

Anyhow, I made performance improvements until I realised that it was
simply going to be impossible to display that many stylesheets in our
UI.

But still, this bug was useful in flushing out some performance issues.

The improvements, in order of decreasing importance are:

(*) Use SfxStyleSheetIterator in SvxStyleToolBoxControl::FillStyleBox to
avoid an O(n^2) situation where the pool repeatedly marks all the
stylesheets as not-used, and then walks the document finding out if a
stylesheet is used. Which is a waste of time because we're searching the
documents pool, so of course they are all used.

(*) Add a virtual method to avoid dynamic_cast

(*) return raw pointers instead of returning rtl::Reference by value to
avoid unnecessary reference counting.

SfxStyleSheetIterator

Change-Id: I15ff9c1846d3ed3e6f5655fa44c762f7619d547a
Reviewed-on: https://gerrit.libreoffice.org/55751Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

include/svl/IndexedStyleSheets.hxx

@@ -109,7 +109,7 @@ public:
      * @internal
      * Method is not const because the returned style sheet is not const
      */
-    rtl::Reference< SfxStyleSheetBase >
+    SfxStyleSheetBase*
     GetStyleSheetByPosition(unsigned pos);
 
     /** Find the position of a provided style.
@@ -155,7 +155,7 @@ public:
     Reindex();
 
     /** Warning: counting for n starts at 0, i.e., the 0th style sheet is the first that is found. */
-    rtl::Reference<SfxStyleSheetBase>
+    SfxStyleSheetBase*
     GetNthStyleSheetThatMatchesPredicate(unsigned n, StyleSheetPredicate& predicate,
             unsigned startAt = 0);
 

include/svl/style.hxx

@@ -176,6 +176,9 @@ public:
     /// If the style has parents, it is _not_ required that the returned item
     /// set has parents (i.e. use it for display purposes only).
     virtual std::unique_ptr<SfxItemSet> GetItemSetForPreview();
+
+    /// Fix for expensive dynamic_cast
+    virtual bool isScStyleSheet() const { return false; }
 };
 
 /* Class to iterate and search on a SfxStyleSheetBasePool */
@@ -243,8 +246,7 @@ protected:
      */
     const svl::IndexedStyleSheets&
                                 GetIndexedStyleSheets() const;
-    rtl::Reference<SfxStyleSheetBase>
-                                GetStyleSheetByPositionInIndex(unsigned pos);
+    SfxStyleSheetBase*          GetStyleSheetByPositionInIndex(unsigned pos);
 
 public:
                                 SfxStyleSheetBasePool( SfxItemPool& );

sc/inc/stlsheet.hxx

@@ -53,6 +53,8 @@ public:
     void                SetUsage( ScStyleSheet::Usage eUse ) const { eUsage = eUse; }
     ScStyleSheet::Usage GetUsage() const { return eUsage; }
 
+    /// Fix for expensive dynamic_cast
+    virtual bool isScStyleSheet() const override { return true; }
 private:
     virtual             ~ScStyleSheet() override;
 

sc/source/core/data/document.cxx

@@ -4956,10 +4956,12 @@ bool ScDocument::IsStyleSheetUsed( const ScStyleSheet& rStyle ) const
         for ( const SfxStyleSheetBase* pStyle = aIter.First(); pStyle;
                                        pStyle = aIter.Next() )
         {
-            const ScStyleSheet* pScStyle = dynamic_cast<const ScStyleSheet*>( pStyle  );
-            if ( pScStyle )
+            if (pStyle->isScStyleSheet())
+            {
+                const ScStyleSheet* pScStyle = static_cast<const ScStyleSheet*>( pStyle  );
                 pScStyle->SetUsage( ScStyleSheet::NOTUSED );
             }
+        }
 
         bool bIsUsed = false;
 

sc/source/core/data/stlpool.cxx

@@ -113,7 +113,7 @@ SfxStyleSheetBase* ScStyleSheetPool::Create( const OUString&   rName,
 
 SfxStyleSheetBase* ScStyleSheetPool::Create( const SfxStyleSheetBase& rStyle )
 {
-    OSL_ENSURE( dynamic_cast<const ScStyleSheet*>( &rStyle) !=  nullptr, "Invalid StyleSheet-class! :-/" );
+    OSL_ENSURE( rStyle.isScStyleSheet(), "Invalid StyleSheet-class! :-/" );
     return new ScStyleSheet( static_cast<const ScStyleSheet&>(rStyle) );
 }
 
@@ -423,14 +423,10 @@ ScStyleSheet* ScStyleSheetPool::FindCaseIns( const OUString& rName, SfxStyleFami
 
     for (/**/;it != aFoundPositions.end(); ++it)
     {
-        SfxStyleSheetBase *pFound = GetStyleSheetByPositionInIndex(*it).get();
-        ScStyleSheet* pSheet = nullptr;
+        SfxStyleSheetBase *pFound = GetStyleSheetByPositionInIndex(*it);
         // we do not know what kind of sheets we have.
-        pSheet = dynamic_cast<ScStyleSheet*>(pFound);
-        if (pSheet != nullptr)
-        {
-            return pSheet;
-        }
+        if (pFound->isScStyleSheet())
+            return static_cast<ScStyleSheet*>(pFound);
     }
     return nullptr;
 }

sd/source/core/stlpool.cxx

@@ -636,11 +636,10 @@ void SdStyleSheetPool::CopySheets(SdStyleSheetPool& rSourcePool, SfxStyleFamily
     for (std::vector<unsigned>::const_iterator it = aSheetsWithFamily.begin();
          it != aSheetsWithFamily.end(); ++it )
     {
-        rtl::Reference<SfxStyleSheetBase> const xSheet =
-            rSourcePool.GetStyleSheetByPositionInIndex( *it );
-        if( !xSheet.is() )
+        SfxStyleSheetBase* pSheet = rSourcePool.GetStyleSheetByPositionInIndex( *it );
+        if( !pSheet )
             continue;
-        rtl::OUString aName( xSheet->GetName() );
+        rtl::OUString aName( pSheet->GetName() );
 
         // now check whether we already have a sheet with the same name
         std::vector<unsigned> aSheetsWithName = GetIndexedStyleSheets().FindPositionsByName(aName);
@@ -650,9 +649,9 @@ void SdStyleSheetPool::CopySheets(SdStyleSheetPool& rSourcePool, SfxStyleFamily
         {
             // if we have a rename suffix, try to find a new name
             pExistingSheet =
-                GetStyleSheetByPositionInIndex(aSheetsWithName.front()).get();
+                GetStyleSheetByPositionInIndex(aSheetsWithName.front());
             if (!rRenameSuffix.isEmpty() &&
-                pExistingSheet->GetItemSet().Equals(xSheet->GetItemSet(), false))
+                pExistingSheet->GetItemSet().Equals(pSheet->GetItemSet(), false))
             {
                 // we have found a sheet with the same name, but different contents. Try to find a new name.
                 // If we already have a sheet with the new name, and it is equal to the one in the source pool,
@@ -664,7 +663,7 @@ void SdStyleSheetPool::CopySheets(SdStyleSheetPool& rSourcePool, SfxStyleFamily
                     aTmpName = aName + rRenameSuffix + OUString::number(nSuffix);
                     pExistingSheet = Find(aTmpName, eFamily);
                     nSuffix++;
-                } while( pExistingSheet && pExistingSheet->GetItemSet().Equals(xSheet->GetItemSet(), false) );
+                } while( pExistingSheet && pExistingSheet->GetItemSet().Equals(pSheet->GetItemSet(), false) );
                 aName = aTmpName;
                 bAddToList = true;
             }
@@ -675,28 +674,28 @@ void SdStyleSheetPool::CopySheets(SdStyleSheetPool& rSourcePool, SfxStyleFamily
             assert(!Find(aName, eFamily));
             rtl::Reference< SfxStyleSheetBase > xNewSheet( &Make( aName, eFamily ) );
 
-            xNewSheet->SetMask( xSheet->GetMask() );
+            xNewSheet->SetMask( pSheet->GetMask() );
 
             // Also set parent relation for copied style sheets
-            OUString aParent( xSheet->GetParent() );
+            OUString aParent( pSheet->GetParent() );
             if( !aParent.isEmpty() )
                 aNewStyles.emplace_back( xNewSheet, aParent );
 
             if( !bAddToList )
             {
                 OUString aHelpFile;
-                xNewSheet->SetHelpId( aHelpFile, xSheet->GetHelpId( aHelpFile ) );
+                xNewSheet->SetHelpId( aHelpFile, pSheet->GetHelpId( aHelpFile ) );
             }
-            xNewSheet->GetItemSet().Put( xSheet->GetItemSet() );
+            xNewSheet->GetItemSet().Put( pSheet->GetItemSet() );
 
             rCreatedSheets.emplace_back( static_cast< SdStyleSheet* >( xNewSheet.get() ) );
-            aRenamedList.emplace_back( xSheet->GetName(), aName );
+            aRenamedList.emplace_back( pSheet->GetName(), aName );
         }
         else if (bAddToList)
         {
             // Add to list - used for renaming
             rCreatedSheets.emplace_back( static_cast< SdStyleSheet* >( pExistingSheet ) );
-            aRenamedList.emplace_back( xSheet->GetName(), aName );
+            aRenamedList.emplace_back( pSheet->GetName(), aName );
         }
     }
 
@@ -939,7 +938,7 @@ void SdStyleSheetPool::UpdateStdNames()
     for (std::vector<unsigned>::const_iterator it = aUserDefinedStyles.begin();
             it != aUserDefinedStyles.end(); ++it)
     {
-        SfxStyleSheetBase* pStyle = GetStyleSheetByPositionInIndex(*it).get();
+        SfxStyleSheetBase* pStyle = GetStyleSheetByPositionInIndex(*it);
 
         if( !pStyle->IsUserDefined() )
         {

svl/source/items/IndexedStyleSheets.cxx

@@ -164,19 +164,19 @@ IndexedStyleSheets::GetNumberOfStyleSheetsWithPredicate(StyleSheetPredicate& pre
     return r;
 }
 
-rtl::Reference<SfxStyleSheetBase>
+SfxStyleSheetBase*
 IndexedStyleSheets::GetNthStyleSheetThatMatchesPredicate(
         unsigned n,
         StyleSheetPredicate& predicate,
         unsigned startAt)
 {
-    rtl::Reference<SfxStyleSheetBase> retval;
+    SfxStyleSheetBase* retval = nullptr;
     unsigned matching = 0;
     for (VectorType::const_iterator it = mStyleSheets.begin()+startAt; it != mStyleSheets.end(); ++it) {
         SfxStyleSheetBase *ssheet = it->get();
         if (predicate.Check(*ssheet)) {
             if (matching == n) {
-                retval = *it;
+                retval = it->get();
                 break;
             }
             ++matching;
@@ -223,11 +223,11 @@ IndexedStyleSheets::HasStyleSheet(const rtl::Reference< SfxStyleSheetBase >& sty
     return false;
 }
 
-rtl::Reference< SfxStyleSheetBase >
+SfxStyleSheetBase*
 IndexedStyleSheets::GetStyleSheetByPosition(unsigned pos)
 {
     if( pos < mStyleSheets.size() )
-        return mStyleSheets.at(pos);
+        return mStyleSheets.at(pos).get();
     return nullptr;
 }
 

svl/source/items/style.cxx

@@ -437,7 +437,7 @@ SfxStyleSheetBase* SfxStyleSheetIterator::operator[](sal_uInt16 nIdx)
     SfxStyleSheetBase* retval = nullptr;
     if( IsTrivialSearch())
     {
-        retval = pBasePool->pImpl->mxIndexedStyleSheets->GetStyleSheetByPosition(nIdx).get();
+        retval = pBasePool->pImpl->mxIndexedStyleSheets->GetStyleSheetByPosition(nIdx);
         nCurrentPosition = nIdx;
     }
     else if(nMask == SfxStyleSearchBits::All)
@@ -491,7 +491,7 @@ SfxStyleSheetBase* SfxStyleSheetIterator::Next()
         if (nStyleSheets > newPosition)
         {
             nCurrentPosition = newPosition;
-            retval = pBasePool->pImpl->mxIndexedStyleSheets->GetStyleSheetByPosition(nCurrentPosition).get();
+            retval = pBasePool->pImpl->mxIndexedStyleSheets->GetStyleSheetByPosition(nCurrentPosition);
         }
     }
     else if(nMask == SfxStyleSearchBits::All)
@@ -502,8 +502,8 @@ SfxStyleSheetBase* SfxStyleSheetIterator::Next()
         if (familyVector.size() > newPosition)
         {
             nCurrentPosition = newPosition;
-            unsigned stylePosition = familyVector.at(newPosition);
-            retval = pBasePool->pImpl->mxIndexedStyleSheets->GetStyleSheetByPosition(stylePosition).get();
+            unsigned stylePosition = familyVector[newPosition];
+            retval = pBasePool->pImpl->mxIndexedStyleSheets->GetStyleSheetByPosition(stylePosition);
         }
     }
     else
@@ -533,7 +533,7 @@ SfxStyleSheetBase* SfxStyleSheetIterator::Find(const OUString& rStr)
     }
 
     unsigned pos = positions.front();
-    SfxStyleSheetBase* pStyle = pBasePool->pImpl->mxIndexedStyleSheets->GetStyleSheetByPosition(pos).get();
+    SfxStyleSheetBase* pStyle = pBasePool->pImpl->mxIndexedStyleSheets->GetStyleSheetByPosition(pos);
     nCurrentPosition = pos;
     pCurrentStyle = pStyle;
     return pCurrentStyle;
@@ -971,7 +971,7 @@ SfxStyleSheetBasePool::GetIndexedStyleSheets() const
     return *pImpl->mxIndexedStyleSheets;
 }
 
-rtl::Reference<SfxStyleSheetBase>
+SfxStyleSheetBase*
 SfxStyleSheetBasePool::GetStyleSheetByPositionInIndex(unsigned pos)
 {
     return pImpl->mxIndexedStyleSheets->GetStyleSheetByPosition(pos);

svx/source/tbxctrls/tbcontrl.cxx

@@ -2409,10 +2409,10 @@ void SvxStyleToolBoxControl::FillStyleBox()
         SfxStyleSheetBase*      pStyle      = nullptr;
         bool                    bDoFill     = false;
 
-        pStyleSheetPool->SetSearchMask( eFamily, SfxStyleSearchBits::Used );
+        SfxStyleSheetIterator aIter( pStyleSheetPool, eFamily, SfxStyleSearchBits::Used );
 
         // Check whether fill is necessary
-        pStyle = pStyleSheetPool->First();
+        pStyle = aIter.First();
         //!!! TODO: This condition isn't right any longer, because we always show some default entries
         //!!! so the list doesn't show the count
         if ( nCount != pBox->GetEntryCount() )
@@ -2425,7 +2425,7 @@ void SvxStyleToolBoxControl::FillStyleBox()
             while ( pStyle && !bDoFill )
             {
                 bDoFill = ( pBox->GetEntry(i) != pStyle->GetName() );
-                pStyle = pStyleSheetPool->Next();
+                pStyle = aIter.Next();
                 i++;
             }
         }
@@ -2436,7 +2436,7 @@ void SvxStyleToolBoxControl::FillStyleBox()
             pBox->Clear();
 
             {
-                pStyle = pStyleSheetPool->First();
+                pStyle = aIter.First();
 
                 if( pImpl->bSpecModeWriter || pImpl->bSpecModeCalc )
                 {
@@ -2456,7 +2456,7 @@ void SvxStyleToolBoxControl::FillStyleBox()
 
                         if( bInsert )
                             pBox->InsertEntry( aName );
-                        pStyle = pStyleSheetPool->Next();
+                        pStyle = aIter.Next();
                     }
                 }
                 else
@@ -2464,7 +2464,7 @@ void SvxStyleToolBoxControl::FillStyleBox()
                     while ( pStyle )
                     {
                         pBox->InsertEntry( pStyle->GetName() );
-                        pStyle = pStyleSheetPool->Next();
+                        pStyle = aIter.Next();
                     }
                 }
             }