Keep prototype maps in dictionary mode until ICs see them

src/ic/ic.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/ic/ic.h"
 
 #include "src/accessors.h"
 #include "src/api-arguments-inl.h"
 #include "src/api.h"
 #include "src/arguments.h"
@@ skipping 205 matching lines @@
   return code;
 }
 
 
 bool IC::AddressIsOptimizedCode() const {
   Code* host =
       isolate()->inner_pointer_to_code_cache()->GetCacheEntry(address())->code;
   return host->kind() == Code::OPTIMIZED_FUNCTION;
 }
 
-
 static void LookupForRead(LookupIterator* it) {
   for (; it->IsFound(); it->Next()) {
     switch (it->state()) {
       case LookupIterator::NOT_FOUND:
       case LookupIterator::TRANSITION:
         UNREACHABLE();
       case LookupIterator::JSPROXY:
         return;
       case LookupIterator::INTERCEPTOR: {
         // If there is a getter, return; otherwise loop to perform the lookup.
@@ skipping 397 matching lines @@
 
       if (use_ic && LoadScriptContextFieldStub::Accepted(&lookup_result)) {
         TRACE_HANDLER_STATS(isolate(), LoadIC_LoadScriptContextFieldStub);
         LoadScriptContextFieldStub stub(isolate(), &lookup_result);
         PatchCache(name, stub.GetCode());
       }
       return result;
     }
   }
 
+  if (state() != UNINITIALIZED) {
+    JSObject::MakePrototypesFast(object, true /* include_receiver */,
+                                 isolate());
+  }
   // Named lookup in the object.
   LookupIterator it(object, name);
   LookupForRead(&it);
 
   if (it.IsFound() || !ShouldThrowReferenceError(object)) {
     // Update inline cache and stub cache.
     if (use_ic) UpdateCaches(&it);
 
     // Get the property.
     Handle<Object> result;
@@ skipping 869 matching lines @@
         Object::SetProperty(object, name, value, language_mode()), Object);
     return result;
   }
 
   // If the object is undefined or null it's illegal to try to set any
   // properties on it; throw a TypeError in that case.
   if (object->IsUndefined(isolate()) || object->IsNull()) {
     return TypeError(MessageTemplate::kNonObjectPropertyStore, object, name);
   }
 
+  if (state() != UNINITIALIZED) {
+    JSObject::MakePrototypesFast(object, false /* include_receiver */,
+                                 isolate());
+  }
   LookupIterator it(object, name);
   if (FLAG_use_ic) UpdateCaches(&it, value, store_mode);
 
   MAYBE_RETURN_NULL(
       Object::SetProperty(&it, value, language_mode(), store_mode));
   return value;
 }
 
 Handle<Code> CallIC::initialize_stub_in_optimized_code(
     Isolate* isolate, int argc, ConvertReceiverMode mode,
@@ skipping 1395 matching lines @@
     DCHECK_EQ(FeedbackVectorSlotKind::KEYED_LOAD_IC,
               vector->GetKind(vector_slot));
     KeyedLoadICNexus nexus(vector, vector_slot);
     KeyedLoadIC ic(IC::EXTRA_CALL_FRAME, isolate, &nexus);
     ic.UpdateState(receiver, key);
     RETURN_RESULT_OR_FAILURE(isolate, ic.Load(receiver, key));
   }
 }
 }  // namespace internal
 }  // namespace v8