[in-place weak refs] Pass MaybeObjectHandles as const&

BUG=v8:7308

Change-Id: I564f340096e64b3d17f9367aea031148a40faf40
Reviewed-on: https://chromium-review.googlesource.com/1218742Reviewed-by: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#55778}

src/compiler/compilation-dependencies.cc

@@ -17,7 +17,7 @@ CompilationDependencies::CompilationDependencies(Isolate* isolate, Zone* zone)
 class CompilationDependencies::Dependency : public ZoneObject {
  public:
   virtual bool IsValid() const = 0;
-  virtual void Install(MaybeObjectHandle code) = 0;
+  virtual void Install(const MaybeObjectHandle& code) = 0;
 };
 
 class InitialMapDependency final : public CompilationDependencies::Dependency {
@@ -36,7 +36,7 @@ class InitialMapDependency final : public CompilationDependencies::Dependency {
            function->initial_map() == *initial_map_.object<Map>();
   }
 
-  void Install(MaybeObjectHandle code) override {
+  void Install(const MaybeObjectHandle& code) override {
     SLOW_DCHECK(IsValid());
     DependentCode::InstallDependency(function_.isolate(), code,
                                      initial_map_.object<Map>(),
@@ -68,7 +68,7 @@ class PrototypePropertyDependency final
            function->prototype() == *prototype_.object();
   }
 
-  void Install(MaybeObjectHandle code) override {
+  void Install(const MaybeObjectHandle& code) override {
     SLOW_DCHECK(IsValid());
     Handle<JSFunction> function = function_.object<JSFunction>();
     if (!function->has_initial_map()) JSFunction::EnsureHasInitialMap(function);
@@ -90,7 +90,7 @@ class StableMapDependency final : public CompilationDependencies::Dependency {
 
   bool IsValid() const override { return map_.object<Map>()->is_stable(); }
 
-  void Install(MaybeObjectHandle code) override {
+  void Install(const MaybeObjectHandle& code) override {
     SLOW_DCHECK(IsValid());
     DependentCode::InstallDependency(map_.isolate(), code, map_.object<Map>(),
                                      DependentCode::kPrototypeCheckGroup);
@@ -108,7 +108,7 @@ class TransitionDependency final : public CompilationDependencies::Dependency {
 
   bool IsValid() const override { return !map_.object<Map>()->is_deprecated(); }
 
-  void Install(MaybeObjectHandle code) override {
+  void Install(const MaybeObjectHandle& code) override {
     SLOW_DCHECK(IsValid());
     DependentCode::InstallDependency(map_.isolate(), code, map_.object<Map>(),
                                      DependentCode::kTransitionGroup);
@@ -132,7 +132,7 @@ class PretenureModeDependency final
     return mode_ == site_.object<AllocationSite>()->GetPretenureMode();
   }
 
-  void Install(MaybeObjectHandle code) override {
+  void Install(const MaybeObjectHandle& code) override {
     SLOW_DCHECK(IsValid());
     DependentCode::InstallDependency(
         site_.isolate(), code, site_.object<AllocationSite>(),
@@ -162,7 +162,7 @@ class FieldTypeDependency final : public CompilationDependencies::Dependency {
     return *type == owner->instance_descriptors()->GetFieldType(descriptor_);
   }
 
-  void Install(MaybeObjectHandle code) override {
+  void Install(const MaybeObjectHandle& code) override {
     SLOW_DCHECK(IsValid());
     DependentCode::InstallDependency(owner_.isolate(), code,
                                      owner_.object<Map>(),
@@ -193,7 +193,7 @@ class GlobalPropertyDependency final
            read_only_ == cell->property_details().IsReadOnly();
   }
 
-  void Install(MaybeObjectHandle code) override {
+  void Install(const MaybeObjectHandle& code) override {
     SLOW_DCHECK(IsValid());
     DependentCode::InstallDependency(cell_.isolate(), code,
                                      cell_.object<PropertyCell>(),
@@ -217,7 +217,7 @@ class ProtectorDependency final : public CompilationDependencies::Dependency {
     return cell->value() == Smi::FromInt(Isolate::kProtectorValid);
   }
 
-  void Install(MaybeObjectHandle code) override {
+  void Install(const MaybeObjectHandle& code) override {
     SLOW_DCHECK(IsValid());
     DependentCode::InstallDependency(cell_.isolate(), code,
                                      cell_.object<PropertyCell>(),
@@ -249,7 +249,7 @@ class ElementsKindDependency final
     return kind_ == kind;
   }
 
-  void Install(MaybeObjectHandle code) override {
+  void Install(const MaybeObjectHandle& code) override {
     SLOW_DCHECK(IsValid());
     DependentCode::InstallDependency(
         site_.isolate(), code, site_.object<AllocationSite>(),
@@ -277,7 +277,7 @@ class InitialMapInstanceSizePredictionDependency final
     return instance_size == instance_size_;
   }
 
-  void Install(MaybeObjectHandle code) override {
+  void Install(const MaybeObjectHandle& code) override {
     DCHECK(IsValid());
     // Finish the slack tracking.
     function_.object<JSFunction>()->CompleteInobjectSlackTrackingIfActive();

src/ic/handler-configuration.cc

@@ -140,7 +140,7 @@ Handle<Object> LoadHandler::LoadFromPrototype(Isolate* isolate,
 // static
 Handle<Object> LoadHandler::LoadFullChain(Isolate* isolate,
                                           Handle<Map> receiver_map,
-                                          MaybeObjectHandle holder,
+                                          const MaybeObjectHandle& holder,
                                           Handle<Smi> smi_handler) {
   Handle<JSReceiver> end;  // null handle, means full prototype chain lookup.
   MaybeObjectHandle data1 = holder;

src/ic/handler-configuration.h

@@ -150,7 +150,7 @@ class LoadHandler final : public DataHandler {
   // needed (e.g., for "nonexistent"), null_value() may be passed in.
   static Handle<Object> LoadFullChain(Isolate* isolate,
                                       Handle<Map> receiver_map,
-                                      MaybeObjectHandle holder,
+                                      const MaybeObjectHandle& holder,
                                       Handle<Smi> smi_handler);
 
   // Creates a data handler that represents a prototype chain check followed

src/objects.cc

@@ -4717,7 +4717,7 @@ Map* Map::FindFieldOwner(Isolate* isolate, int descriptor) const {
 void Map::UpdateFieldType(Isolate* isolate, int descriptor, Handle<Name> name,
                           PropertyConstness new_constness,
                           Representation new_representation,
-                          MaybeObjectHandle new_wrapped_type) {
+                          const MaybeObjectHandle& new_wrapped_type) {
   DCHECK(new_wrapped_type->IsSmi() || new_wrapped_type->IsWeakHeapObject());
   // We store raw pointers in the queue, so no allocations are allowed.
   DisallowHeapAllocation no_allocation;
@@ -10525,7 +10525,7 @@ Handle<ArrayList> ArrayList::EnsureSpace(Isolate* isolate,
 // static
 Handle<WeakArrayList> WeakArrayList::AddToEnd(Isolate* isolate,
                                               Handle<WeakArrayList> array,
-                                              MaybeObjectHandle value) {
+                                              const MaybeObjectHandle& value) {
   int length = array->length();
   array = EnsureSpace(isolate, array, length + 1);
   // Reload length; GC might have removed elements from the array.
@@ -10563,7 +10563,7 @@ int WeakArrayList::CountLiveWeakReferences() const {
   return live_weak_references;
 }
 
-bool WeakArrayList::RemoveOne(MaybeObjectHandle value) {
+bool WeakArrayList::RemoveOne(const MaybeObjectHandle& value) {
   if (length() == 0) return false;
   // Optimize for the most recently added element to be removed again.
   int last_index = length() - 1;
@@ -15319,7 +15319,8 @@ void DependentCode::SetDependentCode(Handle<HeapObject> object,
   }
 }
 
-void DependentCode::InstallDependency(Isolate* isolate, MaybeObjectHandle code,
+void DependentCode::InstallDependency(Isolate* isolate,
+                                      const MaybeObjectHandle& code,
                                       Handle<HeapObject> object,
                                       DependencyGroup group) {
   Handle<DependentCode> old_deps(DependentCode::GetDependentCode(object),
@@ -15333,7 +15334,7 @@ void DependentCode::InstallDependency(Isolate* isolate, MaybeObjectHandle code,
 
 Handle<DependentCode> DependentCode::InsertWeakCode(
     Isolate* isolate, Handle<DependentCode> entries, DependencyGroup group,
-    MaybeObjectHandle code) {
+    const MaybeObjectHandle& code) {
   if (entries->length() == 0 || entries->group() > group) {
     // There is no such group.
     return DependentCode::New(isolate, group, code, entries);
@@ -15366,7 +15367,7 @@ Handle<DependentCode> DependentCode::InsertWeakCode(
 
 Handle<DependentCode> DependentCode::New(Isolate* isolate,
                                          DependencyGroup group,
-                                         MaybeObjectHandle object,
+                                         const MaybeObjectHandle& object,
                                          Handle<DependentCode> next) {
   Handle<DependentCode> result = Handle<DependentCode>::cast(
       isolate->factory()->NewWeakFixedArray(kCodesStartIndex + 1, TENURED));

src/objects/code.h

@@ -624,7 +624,7 @@ class DependentCode : public WeakFixedArray {
   };
 
   // Register a code dependency of {cell} on {object}.
-  static void InstallDependency(Isolate* isolate, MaybeObjectHandle code,
+  static void InstallDependency(Isolate* isolate, const MaybeObjectHandle& code,
                                 Handle<HeapObject> object,
                                 DependencyGroup group);
 
@@ -650,14 +650,14 @@ class DependentCode : public WeakFixedArray {
                                Handle<DependentCode> dep);
 
   static Handle<DependentCode> New(Isolate* isolate, DependencyGroup group,
-                                   MaybeObjectHandle object,
+                                   const MaybeObjectHandle& object,
                                    Handle<DependentCode> next);
   static Handle<DependentCode> EnsureSpace(Isolate* isolate,
                                            Handle<DependentCode> entries);
   static Handle<DependentCode> InsertWeakCode(Isolate* isolate,
                                               Handle<DependentCode> entries,
                                               DependencyGroup group,
-                                              MaybeObjectHandle code);
+                                              const MaybeObjectHandle& code);
 
   // Compact by removing cleared weak cells and return true if there was
   // any cleared weak cell.

src/objects/fixed-array.h

@@ -334,7 +334,7 @@ class WeakArrayList : public HeapObject {
 
   static Handle<WeakArrayList> AddToEnd(Isolate* isolate,
                                         Handle<WeakArrayList> array,
-                                        MaybeObjectHandle value);
+                                        const MaybeObjectHandle& value);
 
   inline MaybeObject* Get(int index) const;
 
@@ -381,7 +381,7 @@ class WeakArrayList : public HeapObject {
   // around in the array - this method can only be used in cases where the user
   // doesn't care about the indices! Users should make sure there are no
   // duplicates.
-  bool RemoveOne(MaybeObjectHandle value);
+  bool RemoveOne(const MaybeObjectHandle& value);
 
   class Iterator {
    public:

src/objects/map.h

@@ -945,7 +945,7 @@ class Map : public HeapObject {
   void UpdateFieldType(Isolate* isolate, int descriptor_number,
                        Handle<Name> name, PropertyConstness new_constness,
                        Representation new_representation,
-                       MaybeObjectHandle new_wrapped_type);
+                       const MaybeObjectHandle& new_wrapped_type);
 
   // TODO(ishell): Move to MapUpdater.
   void PrintReconfiguration(Isolate* isolate, FILE* file, int modify_index,

src/property.cc

@@ -25,7 +25,7 @@ std::ostream& operator<<(std::ostream& os,
 
 Descriptor::Descriptor() : details_(Smi::kZero) {}
 
-Descriptor::Descriptor(Handle<Name> key, MaybeObjectHandle value,
+Descriptor::Descriptor(Handle<Name> key, const MaybeObjectHandle& value,
                        PropertyKind kind, PropertyAttributes attributes,
                        PropertyLocation location, PropertyConstness constness,
                        Representation representation, int field_index)
@@ -37,7 +37,7 @@ Descriptor::Descriptor(Handle<Name> key, MaybeObjectHandle value,
   DCHECK_IMPLIES(key->IsPrivate(), !details_.IsEnumerable());
 }
 
-Descriptor::Descriptor(Handle<Name> key, MaybeObjectHandle value,
+Descriptor::Descriptor(Handle<Name> key, const MaybeObjectHandle& value,
                        PropertyDetails details)
     : key_(key), value_(value), details_(details) {
   DCHECK(key->IsUniqueName());
@@ -55,7 +55,7 @@ Descriptor Descriptor::DataField(Handle<Name> key, int field_index,
                                  PropertyAttributes attributes,
                                  PropertyConstness constness,
                                  Representation representation,
-                                 MaybeObjectHandle wrapped_field_type) {
+                                 const MaybeObjectHandle& wrapped_field_type) {
   DCHECK(wrapped_field_type->IsSmi() || wrapped_field_type->IsWeakHeapObject());
   PropertyDetails details(kData, attributes, kField, constness, representation,
                           field_index);

src/property.h

@@ -40,7 +40,7 @@ class Descriptor final BASE_EMBEDDED {
                               PropertyAttributes attributes,
                               PropertyConstness constness,
                               Representation representation,
-                              MaybeObjectHandle wrapped_field_type);
+                              const MaybeObjectHandle& wrapped_field_type);
 
   static Descriptor DataConstant(Handle<Name> key, Handle<Object> value,
                                  PropertyAttributes attributes);
@@ -58,13 +58,13 @@ class Descriptor final BASE_EMBEDDED {
   PropertyDetails details_;
 
  protected:
-  Descriptor(Handle<Name> key, MaybeObjectHandle value,
+  Descriptor(Handle<Name> key, const MaybeObjectHandle& value,
              PropertyDetails details);
 
-  Descriptor(Handle<Name> key, MaybeObjectHandle value, PropertyKind kind,
-             PropertyAttributes attributes, PropertyLocation location,
-             PropertyConstness constness, Representation representation,
-             int field_index);
+  Descriptor(Handle<Name> key, const MaybeObjectHandle& value,
+             PropertyKind kind, PropertyAttributes attributes,
+             PropertyLocation location, PropertyConstness constness,
+             Representation representation, int field_index);
 
   friend class MapUpdater;
 };