Use a dictionary-mode code cache on the map rather than a dual system.

src/ic/arm64/handler-compiler-arm64.cc

 // Copyright 2014 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.
 
 #if V8_TARGET_ARCH_ARM64
 
 #include "src/ic/handler-compiler.h"
 
 #include "src/api-arguments.h"
 #include "src/field-type.h"
@@ skipping 364 matching lines @@
   Counters* counters = isolate()->counters();
   __ IncrementCounter(counters->ic_named_load_global_stub(), 1, x1, x3);
   if (IC::ICUseVector(kind())) {
     DiscardVectorAndSlot();
   }
   __ Ret();
 
   FrontendFooter(name, &miss);
 
   // Return the generated code.
-  return GetCode(kind(), Code::NORMAL, name);
+  return GetCode(kind(), name);
 }
 
 
 Register NamedStoreHandlerCompiler::value() {
   return StoreDescriptor::ValueRegister();
 }
 
 
 void NamedStoreHandlerCompiler::GenerateRestoreName(Label* label,
                                                     Handle<Name> name) {
@@ skipping 379 matching lines @@
     __ Mov(scratch1(), Operand(cell));
   }
   __ Mov(scratch2(), Operand(name));
   __ Push(receiver(), holder_reg, scratch1(), scratch2(), value());
   __ Push(Smi::FromInt(language_mode));
 
   // Do tail-call to the runtime system.
   __ TailCallRuntime(Runtime::kStoreCallbackProperty);
 
   // Return the generated code.
-  return GetCode(kind(), Code::FAST, name);
+  return GetCode(kind(), name);
 }
 
 
 #undef __
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_IA32