Optimize collapsed border calculation (step 1)

third_party/WebKit/Source/core/layout/LayoutTable.h

 /*
  * Copyright (C) 1997 Martin Jones (mjones@kde.org)
  *           (C) 1997 Torben Weis (weis@kde.org)
  *           (C) 1998 Waldo Bastian (bastian@kde.org)
  *           (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2009, 2010 Apple Inc.
  *               All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 398 matching lines @@
   LayoutTableCell* CellBelow(const LayoutTableCell*) const;
   LayoutTableCell* CellBefore(const LayoutTableCell*) const;
   LayoutTableCell* CellAfter(const LayoutTableCell*) const;
 
   using CollapsedBorderValues = Vector<CollapsedBorderValue>;
   const CollapsedBorderValues& CollapsedBorders() const {
     DCHECK(collapsed_borders_valid_);
     return collapsed_borders_;
   }
   void InvalidateCollapsedBorders();
+  void InvalidateCollapsedBordersForAllCellsIfNeeded();
 
   bool HasSections() const { return Header() || Footer() || FirstBody(); }
 
   void RecalcSectionsIfNeeded() const {
     if (needs_section_recalc_)
       RecalcSections();
   }
 
   static LayoutTable* CreateAnonymousWithParent(const LayoutObject*);
   LayoutBox* CreateAnonymousBoxWithSameTypeAs(
@@ skipping 152 matching lines @@
   std::unique_ptr<TableLayoutAlgorithm> table_layout_;
 
   // A sorted list of all unique border values that we want to paint.
   //
   // Collapsed borders are SUPER EXPENSIVE to compute. The reason is that we
   // need to compare a cells border against all the adjoining cells, rows,
   // row groups, column, column groups and table. Thus we cache them in this
   // field.
   CollapsedBorderValues collapsed_borders_;
   bool collapsed_borders_valid_ : 1;
+  bool needs_invalidate_collapsed_borders_for_all_cells_ : 1;
 
   mutable bool has_col_elements_ : 1;
   mutable bool needs_section_recalc_ : 1;
 
   bool column_logical_width_changed_ : 1;
   mutable bool column_layout_objects_valid_ : 1;
   mutable unsigned no_cell_colspan_at_least_;
   unsigned CalcNoCellColspanAtLeast() const {
     for (unsigned c = 0; c < NumEffectiveColumns(); c++) {
       if (effective_columns_[c].span > 1)
@@ skipping 19 matching lines @@
   if (first_body_)
     return first_body_;
   return foot_;
 }
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutTable, IsTable());
 
 }  // namespace blink
 
 #endif  // LayoutTable_h