Compute multi-line lazily for inline painting

Computing whether an inline block spans multiple lines is more expensive
than expected thus causing a small paint performance regression for both
legacy layout and LayoutNG. This patch moves the computation to use-time
thereby avoiding it when cached drawings are used or paint isn't needed.

Bug: 714962
Cq-Include-Trybots: luci.chromium.try:linux_layout_tests_layout_ng;luci.chromium.try:linux_layout_tests_slimming_paint_v2;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I97380b2e304c3c3293514ecf118fffdf6f9b9292
Reviewed-on: https://chromium-review.googlesource.com/1170310Reviewed-by: Philip Rogers <pdr@chromium.org>
Commit-Queue: Emil A Eklund <eae@chromium.org>
Cr-Commit-Position: refs/heads/master@{#582501}

third_party/blink/renderer/core/paint/inline_box_painter_base.cc

@@ -19,6 +19,7 @@ void InlineBoxPainterBase::PaintBoxDecorationBackground(
     const LayoutPoint& paint_offset,
     LayoutRect adjusted_frame_rect,
     BackgroundImageGeometry geometry,
+    bool object_has_multiple_boxes,
     bool include_logical_left_edge,
     bool include_logical_right_edge) {
   // Shadow comes first and is behind the background and border.
@@ -27,14 +28,14 @@ void InlineBoxPainterBase::PaintBoxDecorationBackground(
   Color background_color =
       line_style_.VisitedDependentColor(GetCSSPropertyBackgroundColor());
   PaintFillLayers(box_painter, paint_info, background_color,
-                  line_style_.BackgroundLayers(), adjusted_frame_rect,
-                  geometry);
+                  line_style_.BackgroundLayers(), adjusted_frame_rect, geometry,
+                  object_has_multiple_boxes);
 
   PaintInsetBoxShadow(paint_info, line_style_, adjusted_frame_rect);
 
   IntRect adjusted_clip_rect;
-  BorderPaintingType border_painting_type =
-      GetBorderPaintType(adjusted_frame_rect, adjusted_clip_rect);
+  BorderPaintingType border_painting_type = GetBorderPaintType(
+      adjusted_frame_rect, adjusted_clip_rect, object_has_multiple_boxes);
   switch (border_painting_type) {
     case kDontPaintBorders:
       break;
@@ -65,12 +66,16 @@ void InlineBoxPainterBase::PaintFillLayers(BoxPainterBase& box_painter,
                                            const FillLayer& layer,
                                            const LayoutRect& rect,
                                            BackgroundImageGeometry& geometry,
+                                           bool object_has_multiple_boxes,
                                            SkBlendMode op) {
   // FIXME: This should be a for loop or similar. It's a little non-trivial to
   // do so, however, since the layers need to be painted in reverse order.
-  if (layer.Next())
-    PaintFillLayers(box_painter, info, c, *layer.Next(), rect, geometry, op);
-  PaintFillLayer(box_painter, info, c, layer, rect, geometry, op);
+  if (layer.Next()) {
+    PaintFillLayers(box_painter, info, c, *layer.Next(), rect, geometry,
+                    object_has_multiple_boxes, op);
+  }
+  PaintFillLayer(box_painter, info, c, layer, rect, geometry,
+                 object_has_multiple_boxes, op);
 }
 
 void InlineBoxPainterBase::PaintFillLayer(BoxPainterBase& box_painter,
@@ -79,11 +84,12 @@ void InlineBoxPainterBase::PaintFillLayer(BoxPainterBase& box_painter,
                                           const FillLayer& fill_layer,
                                           const LayoutRect& paint_rect,
                                           BackgroundImageGeometry& geometry,
+                                          bool object_has_multiple_boxes,
                                           SkBlendMode op) {
   StyleImage* img = fill_layer.GetImage();
   bool has_fill_image = img && img->CanRender();
 
-  if (!object_has_multiple_boxes_ ||
+  if (!object_has_multiple_boxes ||
       (!has_fill_image && !style_.HasBorderRadius())) {
     box_painter.PaintFillLayer(paint_info, c, fill_layer, paint_rect,
                                kBackgroundBleedNone, geometry, op, false);
@@ -91,7 +97,7 @@ void InlineBoxPainterBase::PaintFillLayer(BoxPainterBase& box_painter,
   }
 
   // Handle fill images that clone or spans multiple lines.
-  bool multi_line = object_has_multiple_boxes_ &&
+  bool multi_line = object_has_multiple_boxes &&
                     style_.BoxDecorationBreak() != EBoxDecorationBreak::kClone;
   LayoutRect rect = multi_line
                         ? PaintRectForImageStrip(paint_rect, style_.Direction())
@@ -103,20 +109,4 @@ void InlineBoxPainterBase::PaintFillLayer(BoxPainterBase& box_painter,
                              paint_rect.Size());
 }
 
-void InlineBoxPainterBase::PaintNormalBoxShadow(const PaintInfo& info,
-                                                const ComputedStyle& s,
-                                                const LayoutRect& paint_rect) {
-  BoxPainterBase::PaintNormalBoxShadow(
-      info, paint_rect, s, include_logical_left_edge_for_box_shadow_,
-      include_logical_right_edge_for_box_shadow_);
-}
-
-void InlineBoxPainterBase::PaintInsetBoxShadow(const PaintInfo& info,
-                                               const ComputedStyle& s,
-                                               const LayoutRect& paint_rect) {
-  BoxPainterBase::PaintInsetBoxShadowWithBorderRect(
-      info, paint_rect, s, include_logical_left_edge_for_box_shadow_,
-      include_logical_right_edge_for_box_shadow_);
-}
-
 }  // namespace blink

third_party/blink/renderer/core/paint/inline_box_painter_base.h

@@ -43,6 +43,7 @@ class InlineBoxPainterBase {
                                     const LayoutPoint& paint_offset,
                                     LayoutRect adjusted_frame_rect,
                                     BackgroundImageGeometry,
+                                    bool object_has_multiple_boxes,
                                     bool include_logical_left_edge,
                                     bool include_logical_right_edge);
 
@@ -53,6 +54,7 @@ class InlineBoxPainterBase {
                        const FillLayer&,
                        const LayoutRect&,
                        BackgroundImageGeometry& geometry,
+                       bool object_has_multiple_boxes,
                        SkBlendMode op = SkBlendMode::kSrcOver);
   void PaintFillLayer(BoxPainterBase&,
                       const PaintInfo&,
@@ -60,13 +62,14 @@ class InlineBoxPainterBase {
                       const FillLayer&,
                       const LayoutRect&,
                       BackgroundImageGeometry& geometry,
+                      bool object_has_multiple_boxes,
                       SkBlendMode op);
-  void PaintNormalBoxShadow(const PaintInfo&,
+  virtual void PaintNormalBoxShadow(const PaintInfo&,
                                     const ComputedStyle&,
-                            const LayoutRect& paint_rect);
-  void PaintInsetBoxShadow(const PaintInfo&,
+                                    const LayoutRect& paint_rect) = 0;
+  virtual void PaintInsetBoxShadow(const PaintInfo&,
                                    const ComputedStyle&,
-                           const LayoutRect& paint_rect);
+                                   const LayoutRect& paint_rect) = 0;
 
   virtual LayoutRect PaintRectForImageStrip(const LayoutRect&,
                                             TextDirection direction) const = 0;
@@ -78,7 +81,8 @@ class InlineBoxPainterBase {
   };
   virtual BorderPaintingType GetBorderPaintType(
       const LayoutRect& adjusted_frame_rect,
-      IntRect& adjusted_clip_rect) const = 0;
+      IntRect& adjusted_clip_rect,
+      bool object_has_multiple_boxes) const = 0;
 
   const ImageResourceObserver& image_observer_;
   Member<const Document> document_;
@@ -89,10 +93,6 @@ class InlineBoxPainterBase {
 
   // Style taking ::first-line into account.
   const ComputedStyle& line_style_;
-
-  bool object_has_multiple_boxes_;
-  bool include_logical_left_edge_for_box_shadow_;
-  bool include_logical_right_edge_for_box_shadow_;
 };
 
 }  // namespace blink

third_party/blink/renderer/core/paint/inline_flow_box_painter.cc

@@ -42,16 +42,6 @@ InlineFlowBoxPainter::InlineFlowBoxPainter(const InlineFlowBox& flow_box)
           flow_box.GetLineLayoutItem().StyleRef(),
           flow_box.GetLineLayoutItem().StyleRef(flow_box.IsFirstLineStyle())),
       inline_flow_box_(flow_box) {
-  object_has_multiple_boxes_ = inline_flow_box_.PrevForSameLayoutObject() ||
-                               inline_flow_box_.NextForSameLayoutObject();
-  bool force_include_logical_edges =
-      (!inline_flow_box_.PrevForSameLayoutObject() &&
-       !inline_flow_box_.NextForSameLayoutObject()) ||
-      !inline_flow_box_.Parent();
-  include_logical_left_edge_for_box_shadow_ =
-      force_include_logical_edges || inline_flow_box_.IncludeLogicalLeftEdge();
-  include_logical_right_edge_for_box_shadow_ =
-      force_include_logical_edges || inline_flow_box_.IncludeLogicalRightEdge();
 }
 
 void InlineFlowBoxPainter::Paint(const PaintInfo& paint_info,
@@ -162,7 +152,8 @@ LayoutRect InlineFlowBoxPainter::PaintRectForImageStrip(
 
 InlineBoxPainterBase::BorderPaintingType
 InlineFlowBoxPainter::GetBorderPaintType(const LayoutRect& adjusted_frame_rect,
-                                         IntRect& adjusted_clip_rect) const {
+                                         IntRect& adjusted_clip_rect,
+                                         bool object_has_multiple_boxes) const {
   adjusted_clip_rect = PixelSnappedIntRect(adjusted_frame_rect);
   if (inline_flow_box_.Parent() &&
       inline_flow_box_.GetLineLayoutItem().StyleRef().HasBorderDecoration()) {
@@ -226,12 +217,14 @@ void InlineFlowBoxPainter::PaintBackgroundBorderShadow(
 
   LayoutRect paint_rect = AdjustedPaintRect(paint_offset);
 
+  bool object_has_multiple_boxes = inline_flow_box_.PrevForSameLayoutObject() ||
+                                   inline_flow_box_.NextForSameLayoutObject();
   const auto& box_model = *ToLayoutBoxModelObject(
       LineLayoutAPIShim::LayoutObjectFrom(inline_flow_box_.BoxModelObject()));
   BackgroundImageGeometry geometry(box_model);
   BoxModelObjectPainter box_painter(box_model, &inline_flow_box_);
   PaintBoxDecorationBackground(box_painter, paint_info, paint_offset,
-                               paint_rect, geometry,
+                               paint_rect, geometry, object_has_multiple_boxes,
                                inline_flow_box_.IncludeLogicalLeftEdge(),
                                inline_flow_box_.IncludeLogicalRightEdge());
 }
@@ -257,12 +250,15 @@ void InlineFlowBoxPainter::PaintMask(const PaintInfo& paint_info,
 
   const auto& mask_nine_piece_image = box_model.StyleRef().MaskBoxImage();
   const auto* mask_box_image = mask_nine_piece_image.GetImage();
+  bool object_has_multiple_boxes = inline_flow_box_.PrevForSameLayoutObject() ||
+                                   inline_flow_box_.NextForSameLayoutObject();
 
   // Figure out if we need to push a transparency layer to render our mask.
   BackgroundImageGeometry geometry(box_model);
   BoxModelObjectPainter box_painter(box_model, &inline_flow_box_);
   PaintFillLayers(box_painter, paint_info, Color::kTransparent,
-                  box_model.StyleRef().MaskLayers(), paint_rect, geometry);
+                  box_model.StyleRef().MaskLayers(), paint_rect, geometry,
+                  object_has_multiple_boxes);
 
   bool has_box_image = mask_box_image && mask_box_image->CanRender();
   if (!has_box_image || !mask_box_image->IsLoaded()) {
@@ -350,4 +346,20 @@ void InlineFlowBoxPainter::RecordHitTestData(const PaintInfo& paint_info,
       TouchActionRect(AdjustedPaintRect(paint_offset), touch_action));
 }
 
+void InlineFlowBoxPainter::PaintNormalBoxShadow(const PaintInfo& info,
+                                                const ComputedStyle& s,
+                                                const LayoutRect& paint_rect) {
+  BoxPainterBase::PaintNormalBoxShadow(
+      info, paint_rect, s, inline_flow_box_.IncludeLogicalLeftEdge(),
+      inline_flow_box_.IncludeLogicalRightEdge());
+}
+
+void InlineFlowBoxPainter::PaintInsetBoxShadow(const PaintInfo& info,
+                                               const ComputedStyle& s,
+                                               const LayoutRect& paint_rect) {
+  BoxPainterBase::PaintInsetBoxShadowWithBorderRect(
+      info, paint_rect, s, inline_flow_box_.IncludeLogicalLeftEdge(),
+      inline_flow_box_.IncludeLogicalRightEdge());
+}
+
 }  // namespace blink

third_party/blink/renderer/core/paint/inline_flow_box_painter.h

@@ -37,6 +37,12 @@ class InlineFlowBoxPainter : public InlineBoxPainterBase {
  protected:
   LayoutRect PaintRectForImageStrip(const LayoutRect&,
                                     TextDirection) const override;
+  void PaintNormalBoxShadow(const PaintInfo&,
+                            const ComputedStyle&,
+                            const LayoutRect& paint_rect) override;
+  void PaintInsetBoxShadow(const PaintInfo&,
+                           const ComputedStyle&,
+                           const LayoutRect& paint_rect) override;
 
  private:
   void PaintBackgroundBorderShadow(const PaintInfo&,
@@ -45,7 +51,8 @@ class InlineFlowBoxPainter : public InlineBoxPainterBase {
 
   BorderPaintingType GetBorderPaintType(
       const LayoutRect& adjusted_frame_rect,
-      IntRect& adjusted_clip_rect) const override;
+      IntRect& adjusted_clip_rect,
+      bool object_has_multiple_boxes) const override;
 
   LayoutRect AdjustedPaintRect(const LayoutPoint& paint_offset) const;
 

third_party/blink/renderer/core/paint/ng/ng_inline_box_fragment_painter.cc

@@ -32,15 +32,6 @@ NGInlineBoxFragmentPainter::NGInlineBoxFragmentPainter(
       border_edges_(NGBorderEdges::FromPhysical(
           inline_box_fragment.PhysicalFragment().BorderEdges(),
           inline_box_fragment.Style().GetWritingMode())) {
-  NGPaintFragment::FragmentRange fragments =
-      inline_box_fragment.InlineFragmentsFor(
-          inline_box_fragment.GetLayoutObject());
-  NGPaintFragment::FragmentRange::iterator iter = fragments.begin();
-  object_has_multiple_boxes_ = ++iter != fragments.end();
-  include_logical_left_edge_for_box_shadow_ =
-      !object_has_multiple_boxes_ || border_edges_.line_left;
-  include_logical_right_edge_for_box_shadow_ =
-      !object_has_multiple_boxes_ || border_edges_.line_right;
 }
 
 void NGInlineBoxFragmentPainter::Paint(const PaintInfo& paint_info,
@@ -87,13 +78,20 @@ void NGInlineBoxFragmentPainter::PaintBackgroundBorderShadow(
   LayoutRect adjusted_frame_rect =
       LayoutRect(adjusted_paint_offset, frame_rect.Size());
 
+  NGPaintFragment::FragmentRange fragments =
+      inline_box_fragment_.InlineFragmentsFor(
+          inline_box_fragment_.GetLayoutObject());
+  NGPaintFragment::FragmentRange::iterator iter = fragments.begin();
+  bool object_has_multiple_boxes = ++iter != fragments.end();
+
   // TODO(eae): Switch to LayoutNG version of BackgroundImageGeometry.
   BackgroundImageGeometry geometry(*static_cast<const LayoutBoxModelObject*>(
       inline_box_fragment_.GetLayoutObject()));
   NGBoxFragmentPainter box_painter(inline_box_fragment_);
   PaintBoxDecorationBackground(
       box_painter, paint_info, paint_offset, adjusted_frame_rect, geometry,
-      border_edges_.line_left, border_edges_.line_right);
+      object_has_multiple_boxes, border_edges_.line_left,
+      border_edges_.line_right);
 }
 
 void NGInlineBoxFragmentPainter::ComputeFragmentOffsetOnLine(
@@ -101,7 +99,6 @@ void NGInlineBoxFragmentPainter::ComputeFragmentOffsetOnLine(
     LayoutUnit* offset_on_line,
     LayoutUnit* total_width) const {
   WritingMode writing_mode = inline_box_fragment_.Style().GetWritingMode();
-  DCHECK(object_has_multiple_boxes_);
   NGPaintFragment::FragmentRange fragments =
       inline_box_fragment_.InlineFragmentsFor(
           inline_box_fragment_.GetLayoutObject());
@@ -139,7 +136,6 @@ LayoutRect NGInlineBoxFragmentPainter::PaintRectForImageStrip(
   // multiple lines, you still paint it as though you had one single line. This
   // means each line has to pick up the background where the previous line left
   // off.
-  DCHECK(object_has_multiple_boxes_);
   LayoutUnit offset_on_line;
   LayoutUnit total_width;
   ComputeFragmentOffsetOnLine(direction, &offset_on_line, &total_width);
@@ -184,7 +180,8 @@ static LayoutRect NGClipRectForNinePieceImageStrip(
 InlineBoxPainterBase::BorderPaintingType
 NGInlineBoxFragmentPainter::GetBorderPaintType(
     const LayoutRect& adjusted_frame_rect,
-    IntRect& adjusted_clip_rect) const {
+    IntRect& adjusted_clip_rect,
+    bool object_has_multiple_boxes) const {
   adjusted_clip_rect = PixelSnappedIntRect(adjusted_frame_rect);
   if (inline_box_fragment_.Parent() &&
       inline_box_fragment_.Style().HasBorderDecoration()) {
@@ -199,7 +196,7 @@ NGInlineBoxFragmentPainter::GetBorderPaintType(
     // The simple case is where we either have no border image or we are the
     // only box for this object.  In those cases only a single call to draw is
     // required.
-    if (!has_border_image || !object_has_multiple_boxes_)
+    if (!has_border_image || !object_has_multiple_boxes)
       return kPaintBordersWithoutClip;
 
     // We have a border image that spans multiple lines.
@@ -211,4 +208,20 @@ NGInlineBoxFragmentPainter::GetBorderPaintType(
   return kDontPaintBorders;
 }
 
+void NGInlineBoxFragmentPainter::PaintNormalBoxShadow(
+    const PaintInfo& info,
+    const ComputedStyle& s,
+    const LayoutRect& paint_rect) {
+  BoxPainterBase::PaintNormalBoxShadow(
+      info, paint_rect, s, border_edges_.line_left, border_edges_.line_right);
+}
+
+void NGInlineBoxFragmentPainter::PaintInsetBoxShadow(
+    const PaintInfo& info,
+    const ComputedStyle& s,
+    const LayoutRect& paint_rect) {
+  BoxPainterBase::PaintInsetBoxShadowWithBorderRect(
+      info, paint_rect, s, border_edges_.line_left, border_edges_.line_right);
+}
+
 }  // namespace blink

third_party/blink/renderer/core/paint/ng/ng_inline_box_fragment_painter.h

@@ -37,7 +37,14 @@ class NGInlineBoxFragmentPainter : public InlineBoxPainterBase {
 
   BorderPaintingType GetBorderPaintType(
       const LayoutRect& adjusted_frame_rect,
-      IntRect& adjusted_clip_rect) const override;
+      IntRect& adjusted_clip_rect,
+      bool object_has_multiple_boxes) const override;
+  void PaintNormalBoxShadow(const PaintInfo&,
+                            const ComputedStyle&,
+                            const LayoutRect& paint_rect) override;
+  void PaintInsetBoxShadow(const PaintInfo&,
+                           const ComputedStyle&,
+                           const LayoutRect& paint_rect) override;
 
  private:
   void PaintBackgroundBorderShadow(const PaintInfo&,