[ic] Restructure API load/store data handlers.

... by "inlining" the Tuple2 object into the data handler.

Bug: v8:7206, v8:5561
Change-Id: I8517b2faa8d13bd16b8ec99c7ea8ab97c73a5f2a
Reviewed-on: https://chromium-review.googlesource.com/819233Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50164}

src/factory.cc

@@ -2780,11 +2780,19 @@ Handle<Map> Factory::ObjectLiteralMapFromCache(Handle<Context> native_context,
 
 Handle<LoadHandler> Factory::NewLoadHandler(int data_count) {
   Handle<Map> map;
-  if (data_count == 1) {
+  switch (data_count) {
+    case 1:
       map = load_handler1_map();
-  } else {
-    DCHECK_EQ(2, data_count);
+      break;
+    case 2:
       map = load_handler2_map();
+      break;
+    case 3:
+      map = load_handler3_map();
+      break;
+    default:
+      UNREACHABLE();
+      break;
   }
   return New<LoadHandler>(map, OLD_SPACE);
 }
@@ -2801,6 +2809,9 @@ Handle<StoreHandler> Factory::NewStoreHandler(int data_count) {
     case 2:
       map = store_handler2_map();
       break;
+    case 3:
+      map = store_handler3_map();
+      break;
     default:
       UNREACHABLE();
       break;

src/ic/accessor-assembler.cc

@@ -31,13 +31,22 @@ Node* AccessorAssembler::LoadHandlerDataField(Node* handler, int data_index) {
                       InstanceTypeEqual(instance_type, STORE_HANDLER_TYPE)));
   int offset = 0;
   int minimum_size = 0;
-  if (data_index == 1) {
+  switch (data_index) {
+    case 1:
       offset = DataHandler::kData1Offset;
       minimum_size = DataHandler::kSizeWithData1;
-  } else {
-    DCHECK_EQ(2, data_index);
+      break;
+    case 2:
       offset = DataHandler::kData2Offset;
       minimum_size = DataHandler::kSizeWithData2;
+      break;
+    case 3:
+      offset = DataHandler::kData3Offset;
+      minimum_size = DataHandler::kSizeWithData3;
+      break;
+    default:
+      UNREACHABLE();
+      break;
   }
   USE(minimum_size);
   CSA_ASSERT(this, UintPtrGreaterThanOrEqual(
@@ -172,7 +181,8 @@ void AccessorAssembler::HandleLoadICHandlerCase(
   BIND(&if_smi_handler);
   {
     HandleLoadICSmiHandlerCase(p, var_holder.value(), var_smi_handler.value(),
-                               miss, exit_point, false, support_elements);
+                               handler, miss, exit_point, false,
+                               support_elements);
   }
 
   BIND(&try_proto_handler);
@@ -246,8 +256,9 @@ Node* AccessorAssembler::LoadDescriptorValue(Node* map, Node* descriptor) {
 }
 
 void AccessorAssembler::HandleLoadICSmiHandlerCase(
-    const LoadICParameters* p, Node* holder, Node* smi_handler, Label* miss,
-    ExitPoint* exit_point, bool throw_reference_error_if_nonexistent,
+    const LoadICParameters* p, Node* holder, Node* smi_handler, Node* handler,
+    Label* miss, ExitPoint* exit_point,
+    bool throw_reference_error_if_nonexistent,
     ElementSupport support_elements) {
   VARIABLE(var_double_value, MachineRepresentation::kFloat64);
   Label rebox_double(this, &var_double_value);
@@ -450,11 +461,18 @@ void AccessorAssembler::HandleLoadICSmiHandlerCase(
   BIND(&api_getter);
   {
     Comment("api_getter");
-    Node* context = LoadWeakCellValueUnchecked(
-        LoadObjectField(holder, Tuple2::kValue1Offset));
-    Node* call_handler_info = LoadWeakCellValueUnchecked(
-        LoadObjectField(holder, Tuple2::kValue2Offset));
-
+    CSA_ASSERT(this, TaggedIsNotSmi(handler));
+    Node* call_handler_info = holder;
+
+    // Context is stored either in data2 or data3 field depending on whether
+    // the access check is enabled for this handler or not.
+    Node* context_cell = Select(
+        IsSetWord<LoadHandler::DoAccessCheckOnReceiverBits>(handler_word),
+        [=] { return LoadHandlerDataField(handler, 3); },
+        [=] { return LoadHandlerDataField(handler, 2); },
+        MachineRepresentation::kTagged);
+
+    Node* context = LoadWeakCellValueUnchecked(context_cell);
     Node* foreign =
         LoadObjectField(call_handler_info, CallHandlerInfo::kJsCallbackOffset);
     Node* callback = LoadObjectField(foreign, Foreign::kForeignAddressOffset,
@@ -709,11 +727,6 @@ void AccessorAssembler::HandleLoadICProtoHandler(
   Branch(IsNull(maybe_holder_cell), &done, &load_from_cached_holder);
 
   BIND(&load_from_cached_holder);
-  {
-    Label unwrap_cell(this), bind_holder(this);
-    Branch(IsWeakCell(maybe_holder_cell), &unwrap_cell, &bind_holder);
-
-    BIND(&unwrap_cell);
   {
     // For regular holders, having passed the receiver map check and the
     // validity cell check implies that |holder| is alive. However, for
@@ -724,13 +737,6 @@ void AccessorAssembler::HandleLoadICProtoHandler(
     Goto(&done);
   }
 
-    BIND(&bind_holder);
-    {
-      var_holder->Bind(maybe_holder_cell);
-      Goto(&done);
-    }
-  }
-
   BIND(&done);
   {
     var_smi_handler->Bind(smi_handler);
@@ -774,8 +780,8 @@ void AccessorAssembler::HandleLoadGlobalICHandlerCase(
                            ICMode::kGlobalIC);
   BIND(&if_smi_handler);
   HandleLoadICSmiHandlerCase(
-      &p, var_holder.value(), var_smi_handler.value(), miss, exit_point,
-      throw_reference_error_if_nonexistent, kOnlyProperties);
+      &p, var_holder.value(), var_smi_handler.value(), handler, miss,
+      exit_point, throw_reference_error_if_nonexistent, kOnlyProperties);
 }
 
 void AccessorAssembler::JumpIfDataProperty(Node* details, Label* writable,
@@ -973,30 +979,20 @@ void AccessorAssembler::HandleStoreICProtoHandler(
       },
       miss, ic_mode);
 
-  VARIABLE(var_transition_map_or_holder, MachineRepresentation::kTagged);
   Label if_transition_map(this), if_holder_object(this);
 
-  {
-    Node* maybe_transition_cell = LoadHandlerDataField(handler, 1);
-    var_transition_map_or_holder.Bind(maybe_transition_cell);
-
-    Label unwrap_cell(this);
-    Branch(IsWeakCell(maybe_transition_cell), &unwrap_cell, &if_holder_object);
-
-    BIND(&unwrap_cell);
-    {
-      Node* maybe_transition = LoadWeakCellValue(maybe_transition_cell, miss);
-      var_transition_map_or_holder.Bind(maybe_transition);
-      Branch(IsMap(maybe_transition), &if_transition_map, &if_holder_object);
-    }
-  }
+  Node* maybe_transition_or_holder_cell = LoadHandlerDataField(handler, 1);
+  Node* maybe_transition_or_holder =
+      LoadWeakCellValue(maybe_transition_or_holder_cell, miss);
+  Branch(IsMap(maybe_transition_or_holder), &if_transition_map,
+         &if_holder_object);
 
   BIND(&if_transition_map);
   {
     Label if_transition_to_constant(this), if_store_normal(this);
 
     Node* holder = p->receiver;
-    Node* transition_map = var_transition_map_or_holder.value();
+    Node* transition_map = maybe_transition_or_holder;
 
     GotoIf(IsDeprecatedMap(transition_map), miss);
     Node* handler_word = SmiUntag(smi_handler);
@@ -1070,7 +1066,7 @@ void AccessorAssembler::HandleStoreICProtoHandler(
   {
     Label if_store_global_proxy(this), if_api_setter(this), if_accessor(this),
         if_native_data_property(this);
-    Node* holder = var_transition_map_or_holder.value();
+    Node* holder = maybe_transition_or_holder;
 
     CSA_ASSERT(this, TaggedIsSmi(smi_handler));
     Node* handler_word = SmiUntag(smi_handler);
@@ -1106,10 +1102,18 @@ void AccessorAssembler::HandleStoreICProtoHandler(
     BIND(&if_api_setter);
     {
       Comment("api_setter");
-      Node* context = LoadWeakCellValueUnchecked(
-          LoadObjectField(holder, Tuple2::kValue1Offset));
-      Node* call_handler_info = LoadWeakCellValueUnchecked(
-          LoadObjectField(holder, Tuple2::kValue2Offset));
+      CSA_ASSERT(this, TaggedIsNotSmi(handler));
+      Node* call_handler_info = holder;
+
+      // Context is stored either in data2 or data3 field depending on whether
+      // the access check is enabled for this handler or not.
+      Node* context_cell = Select(
+          IsSetWord<LoadHandler::DoAccessCheckOnReceiverBits>(handler_word),
+          [=] { return LoadHandlerDataField(handler, 3); },
+          [=] { return LoadHandlerDataField(handler, 2); },
+          MachineRepresentation::kTagged);
+
+      Node* context = LoadWeakCellValueUnchecked(context_cell);
 
       Node* foreign = LoadObjectField(call_handler_info,
                                       CallHandlerInfo::kJsCallbackOffset);
@@ -2338,6 +2342,8 @@ void AccessorAssembler::LoadGlobalIC_TryHandlerCase(const LoadICParameters* pp,
 
   bool throw_reference_error_if_nonexistent = typeof_mode == NOT_INSIDE_TYPEOF;
 
+  // TODO(ishell): revisit if this way of code organization still improves
+  // things given that we don't have array handlers anymore.
   {
     LoadICParameters p = *pp;
     DCHECK_NULL(p.receiver);
@@ -2345,7 +2351,7 @@ void AccessorAssembler::LoadGlobalIC_TryHandlerCase(const LoadICParameters* pp,
     p.receiver =
         LoadContextElement(native_context, Context::GLOBAL_PROXY_INDEX);
     Node* holder = LoadContextElement(native_context, Context::EXTENSION_INDEX);
-    HandleLoadICSmiHandlerCase(&p, holder, handler, miss, exit_point,
+    HandleLoadICSmiHandlerCase(&p, holder, handler, handler, miss, exit_point,
                                throw_reference_error_if_nonexistent,
                                kOnlyProperties);
   }

src/ic/accessor-assembler.h

@@ -146,7 +146,7 @@ class AccessorAssembler : public CodeStubAssembler {
       ElementSupport support_elements = kOnlyProperties);
 
   void HandleLoadICSmiHandlerCase(const LoadICParameters* p, Node* holder,
-                                  Node* smi_handler, Label* miss,
+                                  Node* smi_handler, Node* handler, Label* miss,
                                   ExitPoint* exit_point,
                                   bool throw_reference_error_if_nonexistent,
                                   ElementSupport support_elements);

src/ic/handler-configuration.cc

@@ -23,14 +23,15 @@ Handle<Smi> SetBitFieldValue(Isolate* isolate, Handle<Smi> smi_handler,
 
 // TODO(ishell): Remove templatezation once we move common bits from
 // Load/StoreHandler to the base class.
-template <typename ICHandler, bool fill_array = true>
-int InitPrototypeChecks(Isolate* isolate, Handle<Map> receiver_map,
-                        Handle<JSReceiver> holder, Handle<Name> name,
-                        Handle<ICHandler> handler,
-                        Handle<Smi>* smi_handler = nullptr) {
-  if (!holder.is_null() && holder->map() == *receiver_map) return 0;
-
+template <typename ICHandler, bool fill_handler = true>
+int InitPrototypeChecksImpl(Isolate* isolate, Handle<ICHandler> handler,
+                            Handle<Smi>* smi_handler, Handle<Map> receiver_map,
+                            Handle<JSReceiver> holder, Handle<Object> data1,
+                            MaybeHandle<Object> maybe_data2) {
   int checks_count = 0;
+  // Holder-is-receiver case itself does not add entries unless there is an
+  // optional data2 value provided.
+
   if (receiver_map->IsPrimitiveMap() ||
       receiver_map->is_access_check_needed()) {
     DCHECK(!receiver_map->IsJSGlobalObjectMap());
@@ -40,7 +41,7 @@ int InitPrototypeChecks(Isolate* isolate, Handle<Map> receiver_map,
     // be used in other native context through the megamorphic stub cache.
     // So we record the original native context to which this handler
     // corresponds.
-    if (fill_array) {
+    if (fill_handler) {
       Handle<Context> native_context = isolate->native_context();
       handler->set_data2(native_context->self_weak_cell());
     } else {
@@ -51,12 +52,29 @@ int InitPrototypeChecks(Isolate* isolate, Handle<Map> receiver_map,
     checks_count++;
   } else if (receiver_map->is_dictionary_map() &&
              !receiver_map->IsJSGlobalObjectMap()) {
-    if (!fill_array) {
+    if (!fill_handler) {
       // Enable lookup on receiver.
       typedef typename ICHandler::LookupOnReceiverBits Bit;
       *smi_handler = SetBitFieldValue<Bit>(isolate, *smi_handler, true);
     }
   }
+  if (fill_handler) {
+    handler->set_data1(*data1);
+  }
+  Handle<Object> data2;
+  if (maybe_data2.ToHandle(&data2)) {
+    if (fill_handler) {
+      // This value will go either to data2 or data3 slot depending on whether
+      // data2 slot is already occupied by native context.
+      if (checks_count == 0) {
+        handler->set_data2(*data2);
+      } else {
+        DCHECK_EQ(1, checks_count);
+        handler->set_data3(*data2);
+      }
+    }
+    checks_count++;
+  }
   return checks_count;
 }
 
@@ -67,12 +85,23 @@ int InitPrototypeChecks(Isolate* isolate, Handle<Map> receiver_map,
 // Returns -1 if the handler has to be compiled or the number of prototype
 // checks otherwise.
 template <typename ICHandler>
-int GetPrototypeCheckCount(Isolate* isolate, Handle<Map> receiver_map,
-                           Handle<JSReceiver> holder, Handle<Name> name,
-                           Handle<Smi>* smi_handler) {
+int GetPrototypeCheckCount(
+    Isolate* isolate, Handle<Smi>* smi_handler, Handle<Map> receiver_map,
+    Handle<JSReceiver> holder, Handle<Object> data1,
+    MaybeHandle<Object> maybe_data2 = MaybeHandle<Object>()) {
   DCHECK_NOT_NULL(smi_handler);
-  return InitPrototypeChecks<ICHandler, false>(
-      isolate, receiver_map, holder, name, Handle<ICHandler>(), smi_handler);
+  return InitPrototypeChecksImpl<ICHandler, false>(isolate, Handle<ICHandler>(),
+                                                   smi_handler, receiver_map,
+                                                   holder, data1, maybe_data2);
+}
+
+template <typename ICHandler>
+void InitPrototypeChecks(
+    Isolate* isolate, Handle<ICHandler> handler, Handle<Map> receiver_map,
+    Handle<JSReceiver> holder, Handle<Object> data1,
+    MaybeHandle<Object> maybe_data2 = MaybeHandle<Object>()) {
+  InitPrototypeChecksImpl<ICHandler, true>(
+      isolate, handler, nullptr, receiver_map, holder, data1, maybe_data2);
 }
 
 }  // namespace
@@ -81,28 +110,28 @@ int GetPrototypeCheckCount(Isolate* isolate, Handle<Map> receiver_map,
 Handle<Object> LoadHandler::LoadFromPrototype(Isolate* isolate,
                                               Handle<Map> receiver_map,
                                               Handle<JSReceiver> holder,
-                                              Handle<Name> name,
                                               Handle<Smi> smi_handler,
-                                              MaybeHandle<Object> maybe_data) {
+                                              MaybeHandle<Object> maybe_data1,
+                                              MaybeHandle<Object> maybe_data2) {
+  Handle<Object> data1;
+  if (!maybe_data1.ToHandle(&data1)) {
+    data1 = Map::GetOrCreatePrototypeWeakCell(holder, isolate);
+  }
+
   int checks_count = GetPrototypeCheckCount<LoadHandler>(
-      isolate, receiver_map, holder, name, &smi_handler);
+      isolate, &smi_handler, receiver_map, holder, data1, maybe_data2);
 
   Handle<Cell> validity_cell =
       Map::GetOrCreatePrototypeChainValidityCell(receiver_map, isolate);
   DCHECK(!validity_cell.is_null());
 
-  Handle<Object> data;
-  if (!maybe_data.ToHandle(&data)) {
-    data = Map::GetOrCreatePrototypeWeakCell(holder, isolate);
-  }
-
   int data_count = 1 + checks_count;
   Handle<LoadHandler> handler = isolate->factory()->NewLoadHandler(data_count);
 
   handler->set_smi_handler(*smi_handler);
   handler->set_validity_cell(*validity_cell);
-  handler->set_data1(*data);
-  InitPrototypeChecks(isolate, receiver_map, holder, name, handler);
+  InitPrototypeChecks(isolate, handler, receiver_map, holder, data1,
+                      maybe_data2);
   return handler;
 }
 
@@ -110,11 +139,11 @@ Handle<Object> LoadHandler::LoadFromPrototype(Isolate* isolate,
 Handle<Object> LoadHandler::LoadFullChain(Isolate* isolate,
                                           Handle<Map> receiver_map,
                                           Handle<Object> holder,
-                                          Handle<Name> name,
                                           Handle<Smi> smi_handler) {
-  Handle<JSReceiver> end;  // null handle
+  Handle<JSReceiver> end;  // null handle, means full prototype chain lookup.
+  Handle<Object> data1 = holder;
   int checks_count = GetPrototypeCheckCount<LoadHandler>(
-      isolate, receiver_map, end, name, &smi_handler);
+      isolate, &smi_handler, receiver_map, end, data1);
 
   Handle<Object> validity_cell =
       Map::GetOrCreatePrototypeChainValidityCell(receiver_map, isolate);
@@ -130,8 +159,7 @@ Handle<Object> LoadHandler::LoadFullChain(Isolate* isolate,
 
   handler->set_smi_handler(*smi_handler);
   handler->set_validity_cell(*validity_cell);
-  handler->set_data1(*holder);
-  InitPrototypeChecks(isolate, receiver_map, end, name, handler);
+  InitPrototypeChecks(isolate, handler, receiver_map, end, data1);
   return handler;
 }
 
@@ -199,10 +227,15 @@ Handle<Smi> StoreHandler::StoreTransition(Isolate* isolate,
 // static
 Handle<Object> StoreHandler::StoreThroughPrototype(
     Isolate* isolate, Handle<Map> receiver_map, Handle<JSReceiver> holder,
-    Handle<Name> name, Handle<Smi> smi_handler,
-    MaybeHandle<Object> maybe_data) {
+    Handle<Smi> smi_handler, MaybeHandle<Object> maybe_data1,
+    MaybeHandle<Object> maybe_data2) {
+  Handle<Object> data1;
+  if (!maybe_data1.ToHandle(&data1)) {
+    data1 = Map::GetOrCreatePrototypeWeakCell(holder, isolate);
+  }
+
   int checks_count = GetPrototypeCheckCount<StoreHandler>(
-      isolate, receiver_map, holder, name, &smi_handler);
+      isolate, &smi_handler, receiver_map, holder, data1, maybe_data2);
 
   Handle<Object> validity_cell =
       Map::GetOrCreatePrototypeChainValidityCell(receiver_map, isolate);
@@ -211,19 +244,14 @@ Handle<Object> StoreHandler::StoreThroughPrototype(
     validity_cell = handle(Smi::kZero, isolate);
   }
 
-  Handle<Object> data;
-  if (!maybe_data.ToHandle(&data)) {
-    data = Map::GetOrCreatePrototypeWeakCell(holder, isolate);
-  }
-
   int data_count = 1 + checks_count;
   Handle<StoreHandler> handler =
       isolate->factory()->NewStoreHandler(data_count);
 
   handler->set_smi_handler(*smi_handler);
   handler->set_validity_cell(*validity_cell);
-  handler->set_data1(*data);
-  InitPrototypeChecks(isolate, receiver_map, holder, name, handler);
+  InitPrototypeChecks(isolate, handler, receiver_map, holder, data1,
+                      maybe_data2);
   return handler;
 }
 
@@ -237,12 +265,11 @@ Handle<Object> StoreHandler::StoreGlobal(Isolate* isolate,
 Handle<Object> StoreHandler::StoreProxy(Isolate* isolate,
                                         Handle<Map> receiver_map,
                                         Handle<JSProxy> proxy,
-                                        Handle<JSReceiver> receiver,
-                                        Handle<Name> name) {
+                                        Handle<JSReceiver> receiver) {
   Handle<Smi> smi_handler = StoreProxy(isolate);
   if (receiver.is_identical_to(proxy)) return smi_handler;
   Handle<WeakCell> holder_cell = isolate->factory()->NewWeakCell(proxy);
-  return StoreThroughPrototype(isolate, receiver_map, proxy, name, smi_handler,
+  return StoreThroughPrototype(isolate, receiver_map, proxy, smi_handler,
                                holder_cell);
 }
 

src/ic/handler-configuration.h

@@ -147,7 +147,7 @@ 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,
-                                      Handle<Object> holder, Handle<Name> name,
+                                      Handle<Object> holder,
                                       Handle<Smi> smi_handler);
 
   // Creates a data handler that represents a prototype chain check followed
@@ -155,8 +155,9 @@ class LoadHandler final : public DataHandler {
   // Can be used only if GetPrototypeCheckCount() returns non negative value.
   static Handle<Object> LoadFromPrototype(
       Isolate* isolate, Handle<Map> receiver_map, Handle<JSReceiver> holder,
-      Handle<Name> name, Handle<Smi> smi_handler,
-      MaybeHandle<Object> maybe_data = MaybeHandle<Object>());
+      Handle<Smi> smi_handler,
+      MaybeHandle<Object> maybe_data1 = MaybeHandle<Object>(),
+      MaybeHandle<Object> maybe_data2 = MaybeHandle<Object>());
 
   // Creates a Smi-handler for loading a non-existent property. Works only as
   // a part of prototype chain check.
@@ -272,8 +273,9 @@ class StoreHandler final : public DataHandler {
 
   static Handle<Object> StoreThroughPrototype(
       Isolate* isolate, Handle<Map> receiver_map, Handle<JSReceiver> holder,
-      Handle<Name> name, Handle<Smi> smi_handler,
-      MaybeHandle<Object> data = MaybeHandle<Object>());
+      Handle<Smi> smi_handler,
+      MaybeHandle<Object> maybe_data1 = MaybeHandle<Object>(),
+      MaybeHandle<Object> maybe_data2 = MaybeHandle<Object>());
 
   static Handle<Object> StoreElementTransition(Isolate* isolate,
                                                Handle<Map> receiver_map,
@@ -282,8 +284,7 @@ class StoreHandler final : public DataHandler {
 
   static Handle<Object> StoreProxy(Isolate* isolate, Handle<Map> receiver_map,
                                    Handle<JSProxy> proxy,
-                                   Handle<JSReceiver> receiver,
-                                   Handle<Name> name);
+                                   Handle<JSReceiver> receiver);
 
   // Creates a handler for storing a property to the property cell of a global
   // object.

src/ic/ic.cc

@@ -669,7 +669,7 @@ void LoadIC::UpdateCaches(LookupIterator* lookup) {
     Handle<Smi> smi_handler = LoadHandler::LoadNonExistent(isolate());
     code = LoadHandler::LoadFullChain(isolate(), receiver_map(),
                                       isolate()->factory()->null_value(),
-                                      lookup->name(), smi_handler);
+                                      smi_handler);
   } else {
     if (IsLoadGlobalIC()) {
       if (lookup->TryLookupCachedProperty()) {
@@ -759,7 +759,7 @@ Handle<Object> LoadIC::ComputeHandler(LookupIterator* lookup) {
         }
         TRACE_HANDLER_STATS(isolate(), LoadIC_LoadNonMaskingInterceptorDH);
         return LoadHandler::LoadFullChain(isolate(), map, holder_ref,
-                                          lookup->name(), smi_handler);
+                                          smi_handler);
       }
 
       if (receiver_is_holder) {
@@ -770,7 +770,7 @@ Handle<Object> LoadIC::ComputeHandler(LookupIterator* lookup) {
 
       TRACE_HANDLER_STATS(isolate(), LoadIC_LoadInterceptorFromPrototypeDH);
       return LoadHandler::LoadFromPrototype(isolate(), map, holder,
-                                            lookup->name(), smi_handler);
+                                            smi_handler);
     }
 
     case LookupIterator::ACCESSOR: {
@@ -836,12 +836,10 @@ Handle<Object> LoadIC::ComputeHandler(LookupIterator* lookup) {
               isolate()->factory()->NewWeakCell(context);
           Handle<WeakCell> data_cell = isolate()->factory()->NewWeakCell(
               call_optimization.api_call_info());
-          Handle<Tuple2> data =
-              isolate()->factory()->NewTuple2(context_cell, data_cell, TENURED);
 
           TRACE_HANDLER_STATS(isolate(), LoadIC_LoadApiGetterFromPrototypeDH);
           return LoadHandler::LoadFromPrototype(
-              isolate(), map, holder, lookup->name(), smi_handler, data);
+              isolate(), map, holder, smi_handler, data_cell, context_cell);
         }
 
         if (holder->HasFastProperties()) {
@@ -856,8 +854,8 @@ Handle<Object> LoadIC::ComputeHandler(LookupIterator* lookup) {
           smi_handler = LoadHandler::LoadGlobal(isolate());
           Handle<WeakCell> cell =
               isolate()->factory()->NewWeakCell(lookup->GetPropertyCell());
-          return LoadHandler::LoadFromPrototype(
-              isolate(), map, holder, lookup->name(), smi_handler, cell);
+          return LoadHandler::LoadFromPrototype(isolate(), map, holder,
+                                                smi_handler, cell);
         } else {
           smi_handler = LoadHandler::LoadNormal(isolate());
 
@@ -867,7 +865,7 @@ Handle<Object> LoadIC::ComputeHandler(LookupIterator* lookup) {
         }
 
         return LoadHandler::LoadFromPrototype(isolate(), map, holder,
-                                              lookup->name(), smi_handler);
+                                              smi_handler);
       }
 
       Handle<AccessorInfo> info = Handle<AccessorInfo>::cast(accessors);
@@ -887,7 +885,7 @@ Handle<Object> LoadIC::ComputeHandler(LookupIterator* lookup) {
       TRACE_HANDLER_STATS(isolate(),
                           LoadIC_LoadNativeDataPropertyFromPrototypeDH);
       return LoadHandler::LoadFromPrototype(isolate(), map, holder,
-                                            lookup->name(), smi_handler);
+                                            smi_handler);
     }
 
     case LookupIterator::DATA: {
@@ -901,8 +899,8 @@ Handle<Object> LoadIC::ComputeHandler(LookupIterator* lookup) {
           smi_handler = LoadHandler::LoadGlobal(isolate());
           Handle<WeakCell> cell =
               isolate()->factory()->NewWeakCell(lookup->GetPropertyCell());
-          return LoadHandler::LoadFromPrototype(
-              isolate(), map, holder, lookup->name(), smi_handler, cell);
+          return LoadHandler::LoadFromPrototype(isolate(), map, holder,
+                                                smi_handler, cell);
         }
 
         smi_handler = LoadHandler::LoadNormal(isolate());
@@ -925,7 +923,7 @@ Handle<Object> LoadIC::ComputeHandler(LookupIterator* lookup) {
         TRACE_HANDLER_STATS(isolate(), LoadIC_LoadConstantFromPrototypeDH);
       }
       return LoadHandler::LoadFromPrototype(isolate(), map, holder,
-                                            lookup->name(), smi_handler);
+                                            smi_handler);
     }
     case LookupIterator::INTEGER_INDEXED_EXOTIC:
       TRACE_HANDLER_STATS(isolate(), LoadIC_LoadIntegerIndexedExoticDH);
@@ -938,7 +936,7 @@ Handle<Object> LoadIC::ComputeHandler(LookupIterator* lookup) {
         return smi_handler;
       }
       return LoadHandler::LoadFromPrototype(isolate(), map, holder_proxy,
-                                            lookup->name(), smi_handler);
+                                            smi_handler);
     }
     case LookupIterator::ACCESS_CHECK:
     case LookupIterator::NOT_FOUND:
@@ -1444,8 +1442,7 @@ Handle<Object> StoreIC::ComputeHandler(LookupIterator* lookup) {
         Handle<WeakCell> cell =
             isolate()->factory()->NewWeakCell(lookup->transition_cell());
         Handle<Object> handler = StoreHandler::StoreThroughPrototype(
-            isolate(), receiver_map(), store_target, lookup->name(),
-            smi_handler, cell);
+            isolate(), receiver_map(), store_target, smi_handler, cell);
         return handler;
       }
       // Currently not handled by CompileStoreTransition.
@@ -1469,7 +1466,7 @@ Handle<Object> StoreIC::ComputeHandler(LookupIterator* lookup) {
 
       Handle<WeakCell> cell = Map::WeakCellForMap(transition);
       Handle<Object> handler = StoreHandler::StoreThroughPrototype(
-          isolate(), receiver_map(), holder, lookup->name(), smi_handler, cell);
+          isolate(), receiver_map(), holder, smi_handler, cell);
       TransitionsAccessor(receiver_map())
           .UpdateHandler(*lookup->name(), *handler);
       return handler;
@@ -1523,8 +1520,8 @@ Handle<Object> StoreIC::ComputeHandler(LookupIterator* lookup) {
         if (receiver.is_identical_to(holder)) return smi_handler;
         TRACE_HANDLER_STATS(isolate(),
                             StoreIC_StoreNativeDataPropertyOnPrototypeDH);
-        return StoreHandler::StoreThroughPrototype(
-            isolate(), receiver_map(), holder, lookup->name(), smi_handler);
+        return StoreHandler::StoreThroughPrototype(isolate(), receiver_map(),
+                                                   holder, smi_handler);
 
       } else if (accessors->IsAccessorPair()) {
         Handle<Object> setter(Handle<AccessorPair>::cast(accessors)->setter(),
@@ -1551,12 +1548,10 @@ Handle<Object> StoreIC::ComputeHandler(LookupIterator* lookup) {
                 isolate()->factory()->NewWeakCell(context);
             Handle<WeakCell> data_cell = isolate()->factory()->NewWeakCell(
                 call_optimization.api_call_info());
-            Handle<Tuple2> data = isolate()->factory()->NewTuple2(
-                context_cell, data_cell, TENURED);
             TRACE_HANDLER_STATS(isolate(), StoreIC_StoreApiSetterOnPrototypeDH);
             return StoreHandler::StoreThroughPrototype(
-                isolate(), receiver_map(), holder, lookup->name(), smi_handler,
-                data);
+                isolate(), receiver_map(), holder, smi_handler, data_cell,
+                context_cell);
           }
           TRACE_GENERIC_IC("incompatible receiver");
           TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
@@ -1574,8 +1569,8 @@ Handle<Object> StoreIC::ComputeHandler(LookupIterator* lookup) {
         if (receiver.is_identical_to(holder)) return smi_handler;
         TRACE_HANDLER_STATS(isolate(), StoreIC_StoreAccessorOnPrototypeDH);
 
-        return StoreHandler::StoreThroughPrototype(
-            isolate(), receiver_map(), holder, lookup->name(), smi_handler);
+        return StoreHandler::StoreThroughPrototype(isolate(), receiver_map(),
+                                                   holder, smi_handler);
       }
       TRACE_HANDLER_STATS(isolate(), StoreIC_SlowStub);
       return slow_stub();
@@ -1626,7 +1621,7 @@ Handle<Object> StoreIC::ComputeHandler(LookupIterator* lookup) {
           Handle<JSReceiver>::cast(lookup->GetReceiver());
       Handle<JSProxy> holder = lookup->GetHolder<JSProxy>();
       return StoreHandler::StoreProxy(isolate(), receiver_map(), holder,
-                                      receiver, lookup->name());
+                                      receiver);
     }
 
     case LookupIterator::INTEGER_INDEXED_EXOTIC:

src/objects-debug.cc

@@ -1357,6 +1357,9 @@ void DataHandler::DataHandlerVerify() {
   if (data_count >= 2) {
     VerifyObjectField(kData2Offset);
   }
+  if (data_count >= 3) {
+    VerifyObjectField(kData3Offset);
+  }
 }
 
 void LoadHandler::LoadHandlerVerify() {

src/objects-printer.cc

@@ -1459,6 +1459,9 @@ void LoadHandler::LoadHandlerPrint(std::ostream& os) {  // NOLINT
   if (data_count >= 2) {
     os << "\n - data2: " << Brief(data2());
   }
+  if (data_count >= 3) {
+    os << "\n - data3: " << Brief(data3());
+  }
   os << "\n";
 }
 
@@ -1474,6 +1477,9 @@ void StoreHandler::StoreHandlerPrint(std::ostream& os) {  // NOLINT
   if (data_count >= 2) {
     os << "\n - data2: " << Brief(data2());
   }
+  if (data_count >= 3) {
+    os << "\n - data3: " << Brief(data3());
+  }
   os << "\n";
 }
 

src/objects.h

@@ -560,9 +560,11 @@ const int kStubMinorKeyBits = kSmiValueSize - kStubMajorKeyBits - 1;
 #define DATA_HANDLER_LIST(V)                        \
   V(LOAD_HANDLER, LoadHandler, 1, load_handler1)    \
   V(LOAD_HANDLER, LoadHandler, 2, load_handler2)    \
+  V(LOAD_HANDLER, LoadHandler, 3, load_handler3)    \
   V(STORE_HANDLER, StoreHandler, 0, store_handler0) \
   V(STORE_HANDLER, StoreHandler, 1, store_handler1) \
-  V(STORE_HANDLER, StoreHandler, 2, store_handler2)
+  V(STORE_HANDLER, StoreHandler, 2, store_handler2) \
+  V(STORE_HANDLER, StoreHandler, 3, store_handler3)
 
 // We use the full 16 bits of the instance_type field to encode heap object
 // instance types. All the high-order bits (bit 7-15) are cleared if the object

src/objects/data-handler-inl.h

@@ -30,6 +30,8 @@ ACCESSORS_CHECKED(DataHandler, data1, Object, kData1Offset,
                   map()->instance_size() >= kSizeWithData1)
 ACCESSORS_CHECKED(DataHandler, data2, Object, kData2Offset,
                   map()->instance_size() >= kSizeWithData2)
+ACCESSORS_CHECKED(DataHandler, data3, Object, kData3Offset,
+                  map()->instance_size() >= kSizeWithData3)
 
 }  // namespace internal
 }  // namespace v8

src/objects/data-handler.h

@@ -29,10 +29,11 @@ class DataHandler : public Struct {
   // Returns number of optional data fields available in the object.
   inline int data_field_count() const;
 
-  // [data1,2]: These are optional general-purpose fields whose content and
+  // [data1-3]: These are optional general-purpose fields whose content and
   // presence depends on the handler kind.
   DECL_ACCESSORS(data1, Object)
   DECL_ACCESSORS(data2, Object)
+  DECL_ACCESSORS(data3, Object)
 
 // Layout description.
 #define DATA_HANDLER_FIELDS(V)         \
@@ -42,7 +43,9 @@ class DataHandler : public Struct {
   V(kData1Offset, kPointerSize)        \
   V(kSizeWithData1, 0)                 \
   V(kData2Offset, kPointerSize)        \
-  V(kSizeWithData2, 0)
+  V(kSizeWithData2, 0)                 \
+  V(kData3Offset, kPointerSize)        \
+  V(kSizeWithData3, 0)
 
   DEFINE_FIELD_OFFSET_CONSTANTS(HeapObject::kHeaderSize, DATA_HANDLER_FIELDS)
 #undef DATA_HANDLER_FIELDS