Optimised UnoCrsrTbl cleanup for faster doc saving

SwDoc has weak_ptr list to notify UnoCrsr instances
when the doc is about to die. These were updated
when each UnoCrsr instance was destroyed.

The first performance issue is the use of a list.
This no doubt is done to avoid the overhead
of removing items at arbitrary position from a
vector. Performance tests show vector is faster
with a large document and ~10k UnoCrsr instances.

More important, there is no need to clean up
the references as frequently as when each
UnoCrsr is destroyed as they are rarely referenced
at all. Having outdated references is no issue either.

The new logic uses a vector and cleans up only
after saving a document and before saving
UnoCrsr instances.

Saving ODT files is now significantly faster for
large documents (100s of pages).

Change-Id: I3895d9d80d174cda9c94b94837e2149e9fadcb42
Reviewed-on: https://gerrit.libreoffice.org/19604
Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Björn Michaelsen <bjoern.michaelsen@canonical.com>

8 files changed, 66 insertions, 58 deletions

diff --git a/sw/inc/doc.hxx b/sw/inc/doc.hxx
index 8cdda43be771..5ee4684a0b33 100644
--- a/sw/inc/doc.hxx
+++ b/sw/inc/doc.hxx
@@ -1643,7 +1643,18 @@ public:
     void dumpAsXml(struct _xmlTextWriter* = 0) const;
 
     std::set<Color> GetDocColors();
-    std::list< std::weak_ptr<SwUnoCrsr> > mvUnoCrsrTbl;
+    std::vector< std::weak_ptr<SwUnoCrsr> > mvUnoCrsrTbl;
+
+    // Remove expired UnoCrsr weak pointers the document keeps to notify about document death.
+    void cleanupUnoCrsrTbl()
+    {
+        // In most cases we'll remove most of the elements.
+        std::vector< std::weak_ptr<SwUnoCrsr> > unoCrsrTbl;
+        std::copy_if(mvUnoCrsrTbl.begin(), mvUnoCrsrTbl.end(),
+                     std::back_inserter(unoCrsrTbl),
+                     [](const std::weak_ptr<SwUnoCrsr>& pWeakPtr) { return !pWeakPtr.expired(); });
+        std::swap(mvUnoCrsrTbl, unoCrsrTbl);
+    }
 
 private:
     // Copies master header to left / first one, if necessary - used by ChgPageDesc().
diff --git a/sw/source/core/doc/CntntIdxStore.cxx b/sw/source/core/doc/CntntIdxStore.cxx
index 0bcfb344757a..fa555627a368 100644
--- a/sw/source/core/doc/CntntIdxStore.cxx
+++ b/sw/source/core/doc/CntntIdxStore.cxx
@@ -378,7 +378,8 @@ void ContentIdxStoreImpl::RestoreFlys(SwDoc* pDoc, updater_t& rUpdater, bool bAu
 
 void ContentIdxStoreImpl::SaveUnoCrsrs(SwDoc* pDoc, sal_uLong nNode, sal_Int32 nContent)
 {
-    for (auto pWeakUnoCrsr : pDoc->mvUnoCrsrTbl)
+    pDoc->cleanupUnoCrsrTbl();
+    for (const auto& pWeakUnoCrsr : pDoc->mvUnoCrsrTbl)
     {
         auto pUnoCrsr(pWeakUnoCrsr.lock());
         if(!pUnoCrsr)
diff --git a/sw/source/core/doc/doc.cxx b/sw/source/core/doc/doc.cxx
index b78dfe75d829..87ca0baefaad 100644
--- a/sw/source/core/doc/doc.cxx
+++ b/sw/source/core/doc/doc.cxx
@@ -1678,9 +1678,9 @@ std::shared_ptr<SwUnoCrsr> SwDoc::CreateUnoCrsr( const SwPosition& rPos, bool bT
 {
     std::shared_ptr<SwUnoCrsr> pNew;
     if( bTblCrsr )
-        pNew.reset(new SwUnoTableCrsr( rPos ));
+        pNew = std::make_shared<SwUnoTableCrsr>(rPos);
     else
-        pNew.reset(new SwUnoCrsr( rPos ));
+        pNew = std::make_shared<SwUnoCrsr>(rPos);
 
     mvUnoCrsrTbl.push_back( pNew );
     return pNew;
diff --git a/sw/source/core/doc/doccorr.cxx b/sw/source/core/doc/doccorr.cxx
index 26b1371304e9..82bd250812de 100644
--- a/sw/source/core/doc/doccorr.cxx
+++ b/sw/source/core/doc/doccorr.cxx
@@ -120,47 +120,46 @@ void PaMCorrAbs( const SwPaM& rRange,
                 lcl_PaMCorrAbs( const_cast<SwPaM &>(*pCrsrShell->GetTableCrs()), aStart, aEnd, aNewPos );
         }
     }
+
+    for(const auto& pWeakUnoCrsr : pDoc->mvUnoCrsrTbl)
     {
-        for(auto pWeakUnoCrsr : pDoc->mvUnoCrsrTbl)
-        {
-            auto pUnoCursor(pWeakUnoCrsr.lock());
-            if(!pUnoCursor)
-                continue;
+        auto pUnoCursor(pWeakUnoCrsr.lock());
+        if(!pUnoCursor)
+            continue;
 
-            bool bChange = false; // has the UNO cursor been corrected?
+        bool bChange = false; // has the UNO cursor been corrected?
 
-            // determine whether the UNO cursor will leave it's designated
-            // section
-            bool const bLeaveSection =
-                pUnoCursor->IsRemainInSection() &&
-                ( lcl_FindUnoCrsrSection( aNewPos.nNode.GetNode() ) !=
-                  lcl_FindUnoCrsrSection(
-                      pUnoCursor->GetPoint()->nNode.GetNode() ) );
+        // determine whether the UNO cursor will leave it's designated
+        // section
+        bool const bLeaveSection =
+            pUnoCursor->IsRemainInSection() &&
+            ( lcl_FindUnoCrsrSection( aNewPos.nNode.GetNode() ) !=
+                lcl_FindUnoCrsrSection(
+                    pUnoCursor->GetPoint()->nNode.GetNode() ) );
 
-            for(SwPaM& rPaM : pUnoCursor->GetRingContainer())
-            {
-                bChange |= lcl_PaMCorrAbs( rPaM, aStart, aEnd, aNewPos );
-            }
+        for(SwPaM& rPaM : pUnoCursor->GetRingContainer())
+        {
+            bChange |= lcl_PaMCorrAbs( rPaM, aStart, aEnd, aNewPos );
+        }
 
-            SwUnoTableCrsr *const pUnoTblCrsr =
-                dynamic_cast<SwUnoTableCrsr *>(pUnoCursor.get());
-            if( pUnoTblCrsr )
+        SwUnoTableCrsr *const pUnoTblCrsr =
+            dynamic_cast<SwUnoTableCrsr *>(pUnoCursor.get());
+        if( pUnoTblCrsr )
+        {
+            for(SwPaM& rPaM : (&pUnoTblCrsr->GetSelRing())->GetRingContainer())
             {
-                for(SwPaM& rPaM : (&pUnoTblCrsr->GetSelRing())->GetRingContainer())
-                {
-                    bChange |=
-                        lcl_PaMCorrAbs( rPaM, aStart, aEnd, aNewPos );
-                }
+                bChange |=
+                    lcl_PaMCorrAbs( rPaM, aStart, aEnd, aNewPos );
             }
+        }
 
-            // if a UNO cursor leaves its designated section, we must inform
-            // (and invalidate) said cursor
-            if (bChange && bLeaveSection)
-            {
-                // the UNO cursor has left its section. We need to notify it!
-                SwMsgPoolItem aHint( RES_UNOCURSOR_LEAVES_SECTION );
-                pUnoCursor->ModifyNotification( &aHint, NULL );
-            }
+        // if a UNO cursor leaves its designated section, we must inform
+        // (and invalidate) said cursor
+        if (bChange && bLeaveSection)
+        {
+            // the UNO cursor has left its section. We need to notify it!
+            SwMsgPoolItem aHint( RES_UNOCURSOR_LEAVES_SECTION );
+            pUnoCursor->ModifyNotification( &aHint, NULL );
         }
     }
 }
@@ -274,25 +273,24 @@ void PaMCorrRel( const SwNodeIndex &rOldNode,
                 lcl_PaMCorrRel1( pCrsrShell->GetTableCrs(), pOldNode, aNewPos, nCntIdx );
        }
     }
+
+    for(const auto& pWeakUnoCrsr : pDoc->mvUnoCrsrTbl)
     {
-        for(auto pWeakUnoCrsr : pDoc->mvUnoCrsrTbl)
+        auto pUnoCrsr(pWeakUnoCrsr.lock());
+        if(!pUnoCrsr)
+            continue;
+        for(SwPaM& rPaM : pUnoCrsr->GetRingContainer())
         {
-            auto pUnoCrsr(pWeakUnoCrsr.lock());
-            if(!pUnoCrsr)
-                continue;
-            for(SwPaM& rPaM : pUnoCrsr->GetRingContainer())
-            {
-                lcl_PaMCorrRel1( &rPaM, pOldNode, aNewPos, nCntIdx );
-            }
+            lcl_PaMCorrRel1( &rPaM, pOldNode, aNewPos, nCntIdx );
+        }
 
-            SwUnoTableCrsr* pUnoTblCrsr =
-                dynamic_cast<SwUnoTableCrsr*>(pUnoCrsr.get());
-            if( pUnoTblCrsr )
+        SwUnoTableCrsr* pUnoTblCrsr =
+            dynamic_cast<SwUnoTableCrsr*>(pUnoCrsr.get());
+        if( pUnoTblCrsr )
+        {
+            for(SwPaM& rPaM : (&pUnoTblCrsr->GetSelRing())->GetRingContainer())
             {
-                for(SwPaM& rPaM : (&pUnoTblCrsr->GetSelRing())->GetRingContainer())
-                {
-                    lcl_PaMCorrRel1( &rPaM, pOldNode, aNewPos, nCntIdx );
-                }
+                lcl_PaMCorrRel1( &rPaM, pOldNode, aNewPos, nCntIdx );
             }
         }
     }
diff --git a/sw/source/core/doc/docnew.cxx b/sw/source/core/doc/docnew.cxx
index 74ab1f130c9b..93820dc8e622 100644
--- a/sw/source/core/doc/docnew.cxx
+++ b/sw/source/core/doc/docnew.cxx
@@ -426,8 +426,7 @@ SwDoc::~SwDoc()
     getIDocumentRedlineAccess().GetExtraRedlineTable().DeleteAndDestroyAll();
 
     const sw::DocDisposingHint aHint;
-    std::vector< std::weak_ptr<SwUnoCrsr> > vCursorsToKill(mvUnoCrsrTbl.begin(), mvUnoCrsrTbl.end());
-    for(auto& pWeakCursor : vCursorsToKill)
+    for(const auto& pWeakCursor : mvUnoCrsrTbl)
     {
         auto pCursor(pWeakCursor.lock());
         if(pCursor)
diff --git a/sw/source/core/unocore/unocrsr.cxx b/sw/source/core/unocore/unocrsr.cxx
index 3aae518e2b93..590ac66f89f0 100644
--- a/sw/source/core/unocore/unocrsr.cxx
+++ b/sw/source/core/unocore/unocrsr.cxx
@@ -43,9 +43,6 @@ SwUnoCrsr::~SwUnoCrsr()
     if( !pDoc->IsInDtor() )
     {
         assert(!static_cast<bool>(SwIterator<SwClient, SwUnoCrsr>(*this).First()));
-        // remove the weak_ptr the document keeps to notify about document death
-        pDoc->mvUnoCrsrTbl.remove_if(
-            [this](const std::weak_ptr<SwUnoCrsr>& pWeakPtr) -> bool { return pWeakPtr.lock().get() == this; });
     }
 
     // delete the whole ring
diff --git a/sw/source/filter/xml/xmlexp.cxx b/sw/source/filter/xml/xmlexp.cxx
index fa980ab8b8a5..0c7ffd555b4c 100644
--- a/sw/source/filter/xml/xmlexp.cxx
+++ b/sw/source/filter/xml/xmlexp.cxx
@@ -298,7 +298,7 @@ sal_uInt32 SwXMLExport::exportDoc( enum XMLTokenEnum eClass )
                  (RedlineMode_t)(( nRedlineMode & nsRedlineMode_t::REDLINE_SHOW_MASK ) | nsRedlineType_t::REDLINE_INSERT ));
     }
 
-     sal_uInt32 nRet = SvXMLExport::exportDoc( eClass );
+    sal_uInt32 nRet = SvXMLExport::exportDoc( eClass );
 
     // now we can restore the redline mode (if we changed it previously)
     if( bSaveRedline )
diff --git a/sw/source/uibase/app/docsh.cxx b/sw/source/uibase/app/docsh.cxx
index 82c0e617a289..9cdaceec28fb 100644
--- a/sw/source/uibase/app/docsh.cxx
+++ b/sw/source/uibase/app/docsh.cxx
@@ -516,6 +516,8 @@ bool SwDocShell::SaveAs( SfxMedium& rMedium )
 
         // Increase RSID
         m_pDoc->setRsid( m_pDoc->getRsid() );
+
+        m_pDoc->cleanupUnoCrsrTbl();
     }
     SetError( nErr ? nErr : nVBWarning, OUString(  OSL_LOG_PREFIX  ) );