tdf#135683 speed up layout of large writer tables

by making dynamic_cast to some SwTable* types faster

Change-Id: I5c5b2525ecfcdf3c0f648f32b4ccc21ba5ac40fc
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/121193
Tested-by: Jenkins
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>

4 files changed, 36 insertions, 1 deletions

diff --git a/sw/inc/calbck.hxx b/sw/inc/calbck.hxx
index 2d873107e069..7f2224671813 100644
--- a/sw/inc/calbck.hxx
+++ b/sw/inc/calbck.hxx
@@ -36,6 +36,9 @@ class SwModify;
 class SwFormat;
 class SfxPoolItem;
 class SwAttrSet;
+class SwCellFrame;
+class SwTabFrame;
+class SwRowFrame;
 
 /*
     SwModify and SwClient cooperate in propagating attribute changes.
@@ -118,6 +121,9 @@ namespace sw
             virtual void SwClientNotify( const SwModify&, const SfxHint& rHint) =0;
         public:
             bool IsLast() const { return !m_pLeft && !m_pRight; }
+            virtual const SwCellFrame* DynCastCellFrame() const { return nullptr; }
+            virtual const SwTabFrame* DynCastTabFrame() const { return nullptr; }
+            virtual const SwRowFrame* DynCastRowFrame() const { return nullptr; }
     };
     enum class IteratorMode { Exact, UnwrapMulti };
 }
@@ -313,6 +319,32 @@ namespace sw
     };
 }
 
+namespace sw::detail
+{
+    // Dynamic casting can be expensive when used a lot, so for certain type combinations,
+    // we have faster routines.
+    template<typename CastDest>
+    inline const CastDest * internal_dyn_cast(const sw::WriterListener * pSource)
+    {
+        return dynamic_cast<const CastDest *>(pSource);
+    }
+    template<>
+    inline const SwCellFrame* internal_dyn_cast(const sw::WriterListener * pSource)
+    {
+        return pSource->DynCastCellFrame();
+    }
+    template<>
+    inline const SwTabFrame* internal_dyn_cast(const sw::WriterListener * pSource)
+    {
+        return pSource->DynCastTabFrame();
+    }
+    template<>
+    inline const SwRowFrame* internal_dyn_cast(const sw::WriterListener * pSource)
+    {
+        return pSource->DynCastRowFrame();
+    }
+} // namespace sw::detail
+
 template<typename TElementType, typename TSource,
         sw::IteratorMode eMode = sw::IteratorMode::Exact> class SwIterator final
     : private sw::ClientIteratorBase
@@ -344,7 +376,7 @@ public:
                     pCurrent = pLE->m_pToTell;
                 }
             }
-            if (dynamic_cast<const TElementType *>(pCurrent) == nullptr)
+            if (sw::detail::internal_dyn_cast<TElementType>(pCurrent) == nullptr)
             {
                 m_pPosition = GetRightOfPos();
                 pCurrent = m_pPosition;
diff --git a/sw/source/core/inc/cellfrm.hxx b/sw/source/core/inc/cellfrm.hxx
index 7a3f393880df..2e34b8a2fddf 100644
--- a/sw/source/core/inc/cellfrm.hxx
+++ b/sw/source/core/inc/cellfrm.hxx
@@ -36,6 +36,7 @@ class SwCellFrame final : public SwLayoutFrame
 
     virtual void Format( vcl::RenderContext* pRenderContext, const SwBorderAttrs *pAttrs = nullptr ) override;
     virtual void SwClientNotify(const SwModify&, const SfxHint&) override;
+    virtual const SwCellFrame* DynCastCellFrame() const override { return this; }
 
 public:
     SwCellFrame( const SwTableBox &, SwFrame*, bool bInsertContent );
diff --git a/sw/source/core/inc/rowfrm.hxx b/sw/source/core/inc/rowfrm.hxx
index 99c12107c64b..ebaae2e1dbc9 100644
--- a/sw/source/core/inc/rowfrm.hxx
+++ b/sw/source/core/inc/rowfrm.hxx
@@ -52,6 +52,7 @@ class SwRowFrame final : public SwLayoutFrame
 
     virtual void MakeAll(vcl::RenderContext* pRenderContext) override;
     virtual void SwClientNotify(const SwModify&, const SfxHint&) override;
+    virtual const SwRowFrame* DynCastRowFrame() const override { return this; }
 
 public:
     SwRowFrame(const SwTableLine&, SwFrame*, bool bInsertContent = true);
diff --git a/sw/source/core/inc/tabfrm.hxx b/sw/source/core/inc/tabfrm.hxx
index 11e61f7c5b31..9df5aac42571 100644
--- a/sw/source/core/inc/tabfrm.hxx
+++ b/sw/source/core/inc/tabfrm.hxx
@@ -124,6 +124,7 @@ class SwTabFrame final: public SwLayoutFrame, public SwFlowFrame
     virtual void SwClientNotify(const SwModify&, const SfxHint&) override;
     // only changes the Framesize, not the PrtArea size
     virtual SwTwips GrowFrame  ( SwTwips, bool bTst = false, bool bInfo = false ) override;
+    virtual const SwTabFrame* DynCastTabFrame() const override { return this; }
 
 public:
     SwTabFrame( SwTable &, SwFrame* );  // calling RegistFlys always after creation _and_pasting!