SP: Optimize calculating cull rects for inline text and ellipsis boxes.

Source/core/layout/line/InlineBox.cpp

 /*
  * Copyright (C) 2003, 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 323 matching lines @@
     if (!UNLIKELY(layoutObject().hasFlippedBlocksWritingMode()))
         return LayoutPoint(point.x(), point.y());
 
     LayoutBlockFlow& block = root().block();
     if (block.style()->isHorizontalWritingMode())
         return LayoutPoint(point.x(), block.size().height() - size.height() - point.y());
 
     return LayoutPoint(block.size().width() - size.width() - point.x(), point.y());
 }
 
-LayoutRect InlineBox::logicalRectToPhysicalRect(const LayoutRect& current)
+void InlineBox::logicalRectToPhysicalRect(LayoutRect& current)
 {
-    LayoutRect retval = current;
+    if (isHorizontal() && !layoutObject().hasFlippedBlocksWritingMode())
+        return;
+
     if (!isHorizontal()) {
-        retval = retval.transposedRect();
+        current = current.transposedRect();
     }
-    retval.setLocation(logicalPositionToPhysicalPoint(retval.location(), retval.size()));
-    return retval;
+    current.setLocation(logicalPositionToPhysicalPoint(current.location(), current.size()));
+    return;

[wkorman, 2015/06/24 00:45:53]

don't need return

 }
 
 void InlineBox::flipForWritingMode(FloatRect& rect)
 {
     if (!UNLIKELY(layoutObject().hasFlippedBlocksWritingMode()))
         return;
     root().block().flipForWritingMode(rect);
 }
 
 FloatPoint InlineBox::flipForWritingMode(const FloatPoint& point)
@@ skipping 31 matching lines @@
 
 void showLineTree(const blink::InlineBox* b)
 {
     if (b)
         b->showLineTreeForThis();
     else
         fprintf(stderr, "Cannot showLineTree for (nil) InlineBox.\n");
 }
 
 #endif