Issue #1742 - Part 1: Refactor rooting base class templates

Based on Bug 1325406

8 files changed, 83 insertions, 159 deletions

diff --git a/js/src/vm/ArrayBufferObject.cpp b/js/src/vm/ArrayBufferObject.cpp
index 1de3d3b1ec..5d355ada9d 100644
--- a/js/src/vm/ArrayBufferObject.cpp
+++ b/js/src/vm/ArrayBufferObject.cpp
@@ -352,7 +352,7 @@ ArrayBufferObject::detach(JSContext* cx, Handle<ArrayBufferObject*> buffer,
     // Update all views of the buffer to account for the buffer having been
     // detached, and clear the buffer's data and list of views.
 
-    auto& innerViews = cx->compartment()->innerViews;
+    auto& innerViews = cx->compartment()->innerViews.get();
     if (InnerViewTable::ViewVector* views = innerViews.maybeViewsUnbarriered(buffer)) {
         for (size_t i = 0; i < views->length(); i++)
             NoteViewBufferWasDetached((*views)[i], newContents, cx);
@@ -427,7 +427,7 @@ ArrayBufferObject::changeContents(JSContext* cx, BufferContents newContents,
     setNewData(cx->runtime()->defaultFreeOp(), newContents, ownsState);
 
     // Update all views.
-    auto& innerViews = cx->compartment()->innerViews;
+    auto& innerViews = cx->compartment()->innerViews.get();
     if (InnerViewTable::ViewVector* views = innerViews.maybeViewsUnbarriered(this)) {
         for (size_t i = 0; i < views->length(); i++)
             changeViewContents(cx, (*views)[i], oldDataPointer, newContents);
diff --git a/js/src/vm/ArrayBufferObject.h b/js/src/vm/ArrayBufferObject.h
index e6dbd30961..87dce34ba1 100644
--- a/js/src/vm/ArrayBufferObject.h
+++ b/js/src/vm/ArrayBufferObject.h
@@ -541,7 +541,6 @@ class InnerViewTable
     typedef Vector<ArrayBufferViewObject*, 1, SystemAllocPolicy> ViewVector;
 
     friend class ArrayBufferObject;
-    friend class WeakCacheBase<InnerViewTable>;
 
   private:
     struct MapGCPolicy {
@@ -602,23 +601,15 @@ class InnerViewTable
     size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf);
 };
 
-template <>
-class WeakCacheBase<InnerViewTable>
+template <typename Wrapper>
+class MutableWrappedPtrOperations<InnerViewTable, Wrapper>
+    : public WrappedPtrOperations<InnerViewTable, Wrapper>
 {
     InnerViewTable& table() {
-        return static_cast<JS::WeakCache<InnerViewTable>*>(this)->get();
-    }
-    const InnerViewTable& table() const {
-        return static_cast<const JS::WeakCache<InnerViewTable>*>(this)->get();
+        return static_cast<Wrapper*>(this)->get();
     }
 
   public:
-    InnerViewTable::ViewVector* maybeViewsUnbarriered(ArrayBufferObject* obj) {
-        return table().maybeViewsUnbarriered(obj);
-    }
-    void removeViews(ArrayBufferObject* obj) { table().removeViews(obj); }
-    void sweepAfterMinorGC() { table().sweepAfterMinorGC(); }
-    bool needsSweepAfterMinorGC() const { return table().needsSweepAfterMinorGC(); }
     size_t sizeOfExcludingThis(mozilla::MallocSizeOf mallocSizeOf) {
         return table().sizeOfExcludingThis(mallocSizeOf);
     }
diff --git a/js/src/vm/Interpreter.cpp b/js/src/vm/Interpreter.cpp
index 56f715e2be..7e3f2a7f1b 100644
--- a/js/src/vm/Interpreter.cpp
+++ b/js/src/vm/Interpreter.cpp
@@ -1613,11 +1613,7 @@ GetSuperEnvFunction(JSContext* cx, InterpreterRegs& regs)
  */
 
 template<typename T>
-class ReservedRootedBase {
-};
-
-template<typename T>
-class ReservedRooted : public ReservedRootedBase<T>
+class ReservedRooted : public RootedBase<T, ReservedRooted<T>>
 {
     Rooted<T>* savedRoot;
 
@@ -1645,14 +1641,6 @@ class ReservedRooted : public ReservedRootedBase<T>
     DECLARE_POINTER_ASSIGN_OPS(ReservedRooted, T)
 };
 
-template <>
-class ReservedRootedBase<Value> : public ValueOperations<ReservedRooted<Value>>
-{};
-
-template <>
-class ReservedRootedBase<Scope*> : public ScopeCastOperation<ReservedRooted<Scope*>>
-{};
-
 static MOZ_NEVER_INLINE bool
 Interpret(JSContext* cx, RunState& state)
 {
diff --git a/js/src/vm/JSONParser.h b/js/src/vm/JSONParser.h
index 6f91391db0..70ed86f58e 100644
--- a/js/src/vm/JSONParser.h
+++ b/js/src/vm/JSONParser.h
@@ -255,10 +255,13 @@ class MOZ_STACK_CLASS JSONParser : public JSONParserBase
     void operator=(const JSONParser& other) = delete;
 };
 
-template <typename CharT>
-struct RootedBase<JSONParser<CharT>> {
+template <typename CharT, typename Wrapper>
+class MutableWrappedPtrOperations<JSONParser<CharT>, Wrapper>
+  : public WrappedPtrOperations<JSONParser<CharT>, Wrapper>
+{
+  public:
     bool parse(MutableHandleValue vp) {
-        return static_cast<Rooted<JSONParser<CharT>>*>(this)->get().parse(vp);
+        return static_cast<Wrapper*>(this)->get().parse(vp);
     }
 };
 
diff --git a/js/src/vm/SavedStacks.h b/js/src/vm/SavedStacks.h
index c6bda2831b..3ea6c40874 100644
--- a/js/src/vm/SavedStacks.h
+++ b/js/src/vm/SavedStacks.h
@@ -265,24 +265,6 @@ class SavedStacks {
         uint32_t column;
     };
 
-    template <typename Outer>
-    struct LocationValueOperations {
-        JSAtom* source() const { return loc().source; }
-        size_t line() const { return loc().line; }
-        uint32_t column() const { return loc().column; }
-      private:
-        const LocationValue& loc() const { return static_cast<const Outer*>(this)->get(); }
-    };
-
-    template <typename Outer>
-    struct MutableLocationValueOperations : public LocationValueOperations<Outer> {
-        void setSource(JSAtom* v) { loc().source = v; }
-        void setLine(size_t v) { loc().line = v; }
-        void setColumn(uint32_t v) { loc().column = v; }
-      private:
-        LocationValue& loc() { return static_cast<Outer*>(this)->get(); }
-    };
-
   private:
     struct PCLocationHasher : public DefaultHasher<PCKey> {
         using ScriptPtrHasher = DefaultHasher<JSScript*>;
@@ -313,15 +295,32 @@ class SavedStacks {
                                   MutableHandle<LocationValue> locationp);
 };
 
-template <>
-class RootedBase<SavedStacks::LocationValue>
-  : public SavedStacks::MutableLocationValueOperations<JS::Rooted<SavedStacks::LocationValue>>
-{};
+template <typename Wrapper>
+struct WrappedPtrOperations<SavedStacks::LocationValue, Wrapper>
+{
+    JSAtom* source() const { return loc().source; }
+    size_t line() const { return loc().line; }
+    uint32_t column() const { return loc().column; }
+
+  private:
+    const SavedStacks::LocationValue& loc() const {
+        return static_cast<const Wrapper*>(this)->get();
+    }
+};
+
+template <typename Wrapper>
+struct MutableWrappedPtrOperations<SavedStacks::LocationValue, Wrapper>
+    : public WrappedPtrOperations<SavedStacks::LocationValue, Wrapper>
+{
+    void setSource(JSAtom* v) { loc().source = v; }
+    void setLine(size_t v) { loc().line = v; }
+    void setColumn(uint32_t v) { loc().column = v; }
 
-template <>
-class MutableHandleBase<SavedStacks::LocationValue>
-  : public SavedStacks::MutableLocationValueOperations<JS::MutableHandle<SavedStacks::LocationValue>>
-{};
+  private:
+    SavedStacks::LocationValue& loc() {
+        return static_cast<Wrapper*>(this)->get();
+    }
+};
 
 UTF8CharsZ
 BuildUTF8StackString(JSContext* cx, HandleObject stack);
diff --git a/js/src/vm/Scope.h b/js/src/vm/Scope.h
index 4f0edcc133..fc1419bb89 100644
--- a/js/src/vm/Scope.h
+++ b/js/src/vm/Scope.h
@@ -22,6 +22,7 @@
 namespace js {
 
 class ModuleObject;
+class Scope;
 
 enum class BindingKind : uint8_t
 {
@@ -224,6 +225,21 @@ class BindingLocation
 };
 
 //
+// Allow using is<T> and as<T> on Rooted<Scope*> and Handle<Scope*>.
+//
+template <typename Wrapper>
+class WrappedPtrOperations<Scope*, Wrapper>
+{
+  public:
+    template <class U>
+    JS::Handle<U*> as() const {
+        const Wrapper& self = *static_cast<const Wrapper*>(this);
+        MOZ_ASSERT_IF(self, self->template is<U>());
+        return Handle<U*>::fromMarkedLocation(reinterpret_cast<U* const*>(self.address()));
+    }
+};
+
+//
 // The base class of all Scopes.
 //
 class Scope : public js::gc::TenuredCell
@@ -1338,10 +1354,10 @@ class MOZ_STACK_CLASS ScopeIter
 // Specializations of Rooted containers for the iterators.
 //
 
-template <typename Outer>
-class BindingIterOperations
+template <typename Wrapper>
+class WrappedPtrOperations<BindingIter, Wrapper>
 {
-    const BindingIter& iter() const { return static_cast<const Outer*>(this)->get(); }
+    const BindingIter& iter() const { return static_cast<const Wrapper*>(this)->get(); }
 
   public:
     bool done() const { return iter().done(); }
@@ -1361,19 +1377,20 @@ class BindingIterOperations
     uint32_t nextEnvironmentSlot() const { return iter().nextEnvironmentSlot(); }
 };
 
-template <typename Outer>
-class MutableBindingIterOperations : public BindingIterOperations<Outer>
+template <typename Wrapper>
+class MutableWrappedPtrOperations<BindingIter, Wrapper>
+  : public WrappedPtrOperations<BindingIter, Wrapper>
 {
-    BindingIter& iter() { return static_cast<Outer*>(this)->get(); }
+    BindingIter& iter() { return static_cast<Wrapper*>(this)->get(); }
 
   public:
     void operator++(int) { iter().operator++(1); }
 };
 
-template <typename Outer>
-class ScopeIterOperations
+template <typename Wrapper>
+class WrappedPtrOperations<ScopeIter, Wrapper>
 {
-    const ScopeIter& iter() const { return static_cast<const Outer*>(this)->get(); }
+    const ScopeIter& iter() const { return static_cast<const Wrapper*>(this)->get(); }
 
   public:
     bool done() const { return iter().done(); }
@@ -1384,69 +1401,16 @@ class ScopeIterOperations
     bool hasSyntacticEnvironment() const { return iter().hasSyntacticEnvironment(); }
 };
 
-template <typename Outer>
-class MutableScopeIterOperations : public ScopeIterOperations<Outer>
+template <typename Wrapper>
+class MutableWrappedPtrOperations<ScopeIter, Wrapper>
+  : public WrappedPtrOperations<ScopeIter, Wrapper>
 {
-    ScopeIter& iter() { return static_cast<Outer*>(this)->get(); }
+    ScopeIter& iter() { return static_cast<Wrapper*>(this)->get(); }
 
   public:
     void operator++(int) { iter().operator++(1); }
 };
 
-#define SPECIALIZE_ROOTING_CONTAINERS(Iter, BaseIter)                    \
-    template <>                                                          \
-    class RootedBase<Iter>                                               \
-      : public Mutable##BaseIter##Operations<JS::Rooted<Iter>>           \
-    { };                                                                 \
-                                                                         \
-    template <>                                                          \
-    class MutableHandleBase<Iter>                                        \
-      : public Mutable##BaseIter##Operations<JS::MutableHandle<Iter>>    \
-    { };                                                                 \
-                                                                         \
-    template <>                                                          \
-    class HandleBase<Iter>                                               \
-      : public BaseIter##Operations<JS::Handle<Iter>>                    \
-    { };                                                                 \
-                                                                         \
-    template <>                                                          \
-    class PersistentRootedBase<Iter>                                     \
-      : public Mutable##BaseIter##Operations<JS::PersistentRooted<Iter>> \
-    { }
-
-SPECIALIZE_ROOTING_CONTAINERS(BindingIter, BindingIter);
-SPECIALIZE_ROOTING_CONTAINERS(PositionalFormalParameterIter, BindingIter);
-SPECIALIZE_ROOTING_CONTAINERS(ScopeIter, ScopeIter);
-
-#undef SPECIALIZE_ROOTING_CONTAINERS
-
-//
-// Allow using is<T> and as<T> on Rooted<Scope*> and Handle<Scope*>.
-//
-
-template <typename Outer>
-struct ScopeCastOperation
-{
-    template <class U>
-    JS::Handle<U*> as() const {
-        const Outer& self = *static_cast<const Outer*>(this);
-        MOZ_ASSERT_IF(self, self->template is<U>());
-        return Handle<U*>::fromMarkedLocation(reinterpret_cast<U* const*>(self.address()));
-    }
-};
-
-template <>
-class RootedBase<Scope*> : public ScopeCastOperation<JS::Rooted<Scope*>>
-{ };
-
-template <>
-class HandleBase<Scope*> : public ScopeCastOperation<JS::Handle<Scope*>>
-{ };
-
-template <>
-class MutableHandleBase<Scope*> : public ScopeCastOperation<JS::MutableHandle<Scope*>>
-{ };
-
 } // namespace js
 
 namespace JS {
diff --git a/js/src/vm/Shape.h b/js/src/vm/Shape.h
index 52b9197da6..b292bd58f2 100644
--- a/js/src/vm/Shape.h
+++ b/js/src/vm/Shape.h
@@ -1264,9 +1264,10 @@ struct InitialShapeEntry
 
     bool needsSweep() {
         Shape* ushape = shape.unbarrieredGet();
-        JSObject* protoObj = proto.proto().raw();
+        TaggedProto uproto = proto.proto().unbarrieredGet();
+        JSObject* protoObj = uproto.raw();
         return (gc::IsAboutToBeFinalizedUnbarriered(&ushape) ||
-                (proto.proto().isObject() && gc::IsAboutToBeFinalizedUnbarriered(&protoObj)));
+                (uproto.isObject() && gc::IsAboutToBeFinalizedUnbarriered(&protoObj)));
     }
 };
 
@@ -1356,9 +1357,10 @@ struct StackShape
     void trace(JSTracer* trc);
 };
 
-template <typename Outer>
-class StackShapeOperations {
-    const StackShape& ss() const { return static_cast<const Outer*>(this)->get(); }
+template <typename Wrapper>
+class WrappedPtrOperations<StackShape, Wrapper>
+{
+    const StackShape& ss() const { return static_cast<const Wrapper*>(this)->get(); }
 
   public:
     bool hasSlot() const { return ss().hasSlot(); }
@@ -1370,9 +1372,11 @@ class StackShapeOperations {
     uint8_t attrs() const { return ss().attrs; }
 };
 
-template <typename Outer>
-class MutableStackShapeOperations : public StackShapeOperations<Outer> {
-    StackShape& ss() { return static_cast<Outer*>(this)->get(); }
+template <typename Wrapper>
+class MutableWrappedPtrOperations<StackShape, Wrapper>
+  : public WrappedPtrOperations<StackShape, Wrapper>
+{
+    StackShape& ss() { return static_cast<Wrapper*>(this)->get(); }
 
   public:
     void updateGetterSetter(GetterOp rawGetter, SetterOp rawSetter) {
@@ -1383,19 +1387,6 @@ class MutableStackShapeOperations : public StackShapeOperations<Outer> {
     void setAttrs(uint8_t attrs) { ss().attrs = attrs; }
 };
 
-template <>
-class RootedBase<StackShape> : public MutableStackShapeOperations<JS::Rooted<StackShape>>
-{};
-
-template <>
-class HandleBase<StackShape> : public StackShapeOperations<JS::Handle<StackShape>>
-{};
-
-template <>
-class MutableHandleBase<StackShape>
-  : public MutableStackShapeOperations<JS::MutableHandle<StackShape>>
-{};
-
 inline
 Shape::Shape(const StackShape& other, uint32_t nfixed)
   : base_(other.base),
diff --git a/js/src/vm/TaggedProto.h b/js/src/vm/TaggedProto.h
index de3e86a7f5..5b9fe5c7e8 100644
--- a/js/src/vm/TaggedProto.h
+++ b/js/src/vm/TaggedProto.h
@@ -77,11 +77,11 @@ struct InternalBarrierMethods<TaggedProto>
     }
 };
 
-template<class Outer>
-class TaggedProtoOperations
+template <class Wrapper>
+class WrappedPtrOperations<TaggedProto, Wrapper>
 {
     const TaggedProto& value() const {
-        return static_cast<const Outer*>(this)->get();
+        return static_cast<const Wrapper*>(this)->get();
     }
 
   public:
@@ -95,18 +95,6 @@ class TaggedProtoOperations
     uint64_t uniqueId() const { return value().uniqueId(); }
 };
 
-template <>
-class HandleBase<TaggedProto> : public TaggedProtoOperations<Handle<TaggedProto>>
-{};
-
-template <>
-class RootedBase<TaggedProto> : public TaggedProtoOperations<Rooted<TaggedProto>>
-{};
-
-template <>
-class BarrieredBaseMixins<TaggedProto> : public TaggedProtoOperations<GCPtr<TaggedProto>>
-{};
-
 // If the TaggedProto is a JSObject pointer, convert to that type and call |f|
 // with the pointer. If the TaggedProto is lazy, calls F::defaultValue.
 template <typename F, typename... Args>