Bug 1304913 - Have Servo manage node data directly without FFI calls. r=Manishearth

MozReview-Commit-ID: H8f8VP18TbM

dom/base/Element.cpp

@@ -1742,7 +1742,7 @@ Element::BindToTree(nsIDocument* aDocument, nsIContent* aParent,
   // So for now, we just mark nodes as dirty when they're inserted into a
   // document or shadow tree.
   if (IsStyledByServo() && IsInComposedDoc()) {
-    MOZ_ASSERT(!ServoData().get());
+    MOZ_ASSERT(!HasServoData());
     SetIsDirtyForServo();
   }
 
@@ -1857,10 +1857,10 @@ Element::UnbindFromTree(bool aDeep, bool aNullParent)
   // Computed styled data isn't useful for detached nodes, and we'll need to
   // recomputed it anyway if we ever insert the nodes back into a document.
   if (IsStyledByServo()) {
-    ServoData().reset();
+    ClearServoData();
   } else {
 #ifdef MOZ_STYLO
-    MOZ_ASSERT(!ServoData());
+    MOZ_ASSERT(!HasServoData());
 #endif
   }
 

dom/base/nsGenericDOMDataNode.cpp

@@ -567,7 +567,7 @@ nsGenericDOMDataNode::BindToTree(nsIDocument* aDocument, nsIContent* aParent,
   // So for now, we just mark nodes as dirty when they're inserted into a
   // document or shadow tree.
   if (IsStyledByServo() && IsInComposedDoc()) {
-    MOZ_ASSERT(!ServoData().get());
+    MOZ_ASSERT(!HasServoData());
     SetIsDirtyForServo();
   }
 
@@ -605,10 +605,10 @@ nsGenericDOMDataNode::UnbindFromTree(bool aDeep, bool aNullParent)
   // Computed styled data isn't useful for detached nodes, and we'll need to
   // recomputed it anyway if we ever insert the nodes back into a document.
   if (IsStyledByServo()) {
-    ServoData().reset();
+    ClearServoData();
   } else {
 #ifdef MOZ_STYLO
-    MOZ_ASSERT(!ServoData());
+    MOZ_ASSERT(!HasServoData());
 #endif
   }
 

dom/base/nsINode.cpp

@@ -152,6 +152,9 @@ nsINode::~nsINode()
 {
   MOZ_ASSERT(!HasSlots(), "nsNodeUtils::LastRelease was not called?");
   MOZ_ASSERT(mSubtreeRoot == this, "Didn't restore state properly?");
+#ifdef MOZ_STYLO
+  ClearServoData();
+#endif
 }
 
 void*

dom/base/nsINode.h

@@ -8,6 +8,7 @@
 #define nsINode_h___
 
 #include "mozilla/Likely.h"
+#include "mozilla/ServoTypes.h"
 #include "mozilla/UniquePtr.h"
 #include "nsCOMPtr.h"               // for member, local
 #include "nsGkAtoms.h"              // for nsGkAtoms::baseURIProperty
@@ -53,21 +54,7 @@ class nsNodeSupportsWeakRefTearoff;
 class nsNodeWeakReference;
 class nsDOMMutationObserver;
 
-// We declare the bare minimum infrastructure here to allow us to have a
-// UniquePtr<ServoNodeData> on nsINode.
-struct ServoNodeData;
-extern "C" void Servo_NodeData_Drop(ServoNodeData*);
-namespace mozilla {
-template<>
-class DefaultDelete<ServoNodeData>
-{
-public:
-  void operator()(ServoNodeData* aPtr) const
-  {
-    Servo_NodeData_Drop(aPtr);
-  }
-};
-} // namespace mozilla
+extern "C" void Servo_Node_ClearNodeData(nsINode*);
 
 namespace mozilla {
 class EventListenerManager;
@@ -2090,9 +2077,17 @@ public:
 #undef TOUCH_EVENT
 #undef EVENT
 
-  mozilla::UniquePtr<ServoNodeData>& ServoData() {
+  bool HasServoData() {
 #ifdef MOZ_STYLO
-    return mServoNodeData;
+    return !!mServoData.Get();
+#else
+    MOZ_CRASH("Accessing servo node data in non-stylo build");
+#endif
+  }
+
+  void ClearServoData() {
+#ifdef MOZ_STYLO
+    Servo_Node_ClearNodeData(this);
 #else
     MOZ_CRASH("Accessing servo node data in non-stylo build");
 #endif
@@ -2137,8 +2132,8 @@ protected:
   nsSlots* mSlots;
 
 #ifdef MOZ_STYLO
-  // Layout data managed by Servo.
-  mozilla::UniquePtr<ServoNodeData> mServoNodeData;
+  // Per-node data managed by Servo.
+  mozilla::ServoCell<ServoNodeData*> mServoData;
 #endif
 };
 

layout/base/ServoRestyleManager.cpp

@@ -386,7 +386,7 @@ ServoRestyleManager::ContentInserted(nsINode* aContainer, nsIContent* aChild)
     return;
   }
 
-  if (!aContainer->ServoData().get()) {
+  if (!aContainer->HasServoData()) {
     // This can happen with display:none. Bug 1297249 tracks more investigation
     // and assertions here.
     return;
@@ -417,7 +417,7 @@ void
 ServoRestyleManager::ContentAppended(nsIContent* aContainer,
                                      nsIContent* aFirstNewContent)
 {
-  if (!aContainer->ServoData().get()) {
+  if (!aContainer->HasServoData()) {
     // This can happen with display:none. Bug 1297249 tracks more investigation
     // and assertions here.
     return;

layout/base/nsCSSFrameConstructor.cpp

@@ -10593,13 +10593,13 @@ nsCSSFrameConstructor::AddFCItemsForAnonymousContent(
       // This happens when a native anonymous node is used to implement a
       // pseudo-element. Allowing Servo to traverse these nodes would be wasted
       // work, so assert that we didn't do that.
-      MOZ_ASSERT_IF(content->IsStyledByServo(), !content->ServoData());
+      MOZ_ASSERT_IF(content->IsStyledByServo(), !content->HasServoData());
       styleContext = aAnonymousItems[i].mStyleContext.forget();
     } else {
       // If we don't have an explicit style context, that means we need the
       // ordinary computed values. Make sure we eagerly cascaded them when the
       // anonymous nodes were created.
-      MOZ_ASSERT_IF(content->IsStyledByServo(), !!content->ServoData());
+      MOZ_ASSERT_IF(content->IsStyledByServo(), content->HasServoData());
       styleContext = ResolveStyleContext(aFrame, content, &aState);
     }
 

layout/style/ServoBindingList.h

@@ -19,7 +19,7 @@
  */
 
 // Node data
-SERVO_BINDING_FUNC(Servo_NodeData_Drop, void, ServoNodeDataOwned data)
+SERVO_BINDING_FUNC(Servo_Node_ClearNodeData, void, RawGeckoNode* node)
 
 // Styleset and Stylesheet management
 SERVO_BINDING_FUNC(Servo_StyleSheet_FromUTF8Bytes, RawServoStyleSheetStrong,

layout/style/ServoBindings.cpp

@@ -569,19 +569,6 @@ SERVO_IMPL_ELEMENT_ATTR_MATCHING_FUNCTIONS(Gecko_Snapshot, ServoElementSnapshot*
 
 #undef SERVO_IMPL_ELEMENT_ATTR_MATCHING_FUNCTIONS
 
-ServoNodeDataBorrowedOrNull
-Gecko_GetNodeData(RawGeckoNodeBorrowed aNode)
-{
-  return aNode->ServoData().get();
-}
-
-void
-Gecko_SetNodeData(RawGeckoNodeBorrowed aNode, ServoNodeDataOwned aData)
-{
-  MOZ_ASSERT(!aNode->ServoData());
-  aNode->ServoData().reset(aData);
-}
-
 nsIAtom*
 Gecko_Atomize(const char* aString, uint32_t aLength)
 {

layout/style/ServoBindings.h

@@ -7,8 +7,12 @@
 #ifndef mozilla_ServoBindings_h
 #define mozilla_ServoBindings_h
 
+#include "mozilla/ServoTypes.h"
 #include "mozilla/ServoElementSnapshot.h"
 #include "mozilla/css/SheetParsingMode.h"
+#include "mozilla/dom/Element.h"
+#include "nsIDocument.h"
+#include "nsINode.h"
 #include "nsChangeHint.h"
 #include "nsColor.h"
 #include "nsProxyRelease.h"
@@ -25,24 +29,17 @@
  */
 
 class nsIAtom;
-class nsINode;
-typedef nsINode RawGeckoNode;
 class nsIPrincipal;
 class nsIURI;
 struct nsFont;
 namespace mozilla {
   class FontFamilyList;
   enum FontFamilyType : uint32_t;
-  namespace dom { class Element; }
 }
 using mozilla::FontFamilyList;
 using mozilla::FontFamilyType;
 using mozilla::dom::Element;
 using mozilla::ServoElementSnapshot;
-typedef mozilla::dom::Element RawGeckoElement;
-class nsIDocument;
-typedef nsIDocument RawGeckoDocument;
-struct ServoNodeData;
 struct ServoComputedValues;
 struct RawServoStyleSheet;
 struct RawServoStyleSet;
@@ -107,8 +104,6 @@ DECL_ARC_REF_TYPE_FOR(RawServoStyleSheet)
 DECL_ARC_REF_TYPE_FOR(ServoDeclarationBlock)
 
 DECL_OWNED_REF_TYPE_FOR(RawServoStyleSet)
-DECL_NULLABLE_OWNED_REF_TYPE_FOR(ServoNodeData)
-DECL_OWNED_REF_TYPE_FOR(ServoNodeData)
 DECL_NULLABLE_OWNED_REF_TYPE_FOR(StyleChildrenIterator)
 DECL_OWNED_REF_TYPE_FOR(StyleChildrenIterator)
 
@@ -223,10 +218,6 @@ SERVO_DECLARE_ELEMENT_ATTR_MATCHING_FUNCTIONS(Gecko_Snapshot,
 // Style attributes.
 ServoDeclarationBlockBorrowedOrNull Gecko_GetServoDeclarationBlock(RawGeckoElementBorrowed element);
 
-// Node data.
-ServoNodeDataBorrowedOrNull Gecko_GetNodeData(RawGeckoNodeBorrowed node);
-void Gecko_SetNodeData(RawGeckoNodeBorrowed node, ServoNodeDataOwned data);
-
 // Atoms.
 nsIAtom* Gecko_Atomize(const char* aString, uint32_t aLength);
 void Gecko_AddRefAtom(nsIAtom* aAtom);

layout/style/ServoTypes.h

@@ -0,0 +1,40 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_ServoTypes_h
+#define mozilla_ServoTypes_h
+
+/*
+ * Type definitions used to interact with Servo. This gets included by nsINode,
+ * so don't add significant include dependencies to this file.
+ */
+
+struct ServoNodeData;
+namespace mozilla {
+
+/*
+ * Replaced types. These get mapped to associated Servo types in bindgen.
+ */
+
+template<typename T>
+struct ServoUnsafeCell {
+  T value;
+
+  // Ensure that primitive types (i.e. pointers) get zero-initialized.
+  ServoUnsafeCell() : value() {};
+};
+
+template<typename T>
+struct ServoCell {
+  ServoUnsafeCell<T> value;
+  T Get() const { return value.value; }
+  void Set(T arg) { value.value = arg; }
+  ServoCell() : value() {};
+};
+
+} // namespace mozilla
+
+#endif // mozilla_ServoTypes_h

layout/style/moz.build

@@ -97,6 +97,7 @@ EXPORTS.mozilla += [
     'ServoElementSnapshot.h',
     'ServoStyleSet.h',
     'ServoStyleSheet.h',
+    'ServoTypes.h',
     'SheetType.h',
     'StyleAnimationValue.h',
     'StyleBackendType.h',

layout/style/nsStyleStruct.h

@@ -47,6 +47,11 @@ class nsTextFrame;
 class imgIContainer;
 struct nsStyleVisibility;
 
+typedef nsINode RawGeckoNode;
+typedef mozilla::dom::Element RawGeckoElement;
+typedef nsIDocument RawGeckoDocument;
+struct ServoNodeData;
+
 // Includes nsStyleStructID.
 #include "nsStyleStructFwd.h"