[turbofan] First steps towards optimizing for-in loops.

src/compiler/js-generic-lowering.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.
 
 #include "src/code-factory.h"
 #include "src/code-stubs.h"
 #include "src/compiler/common-operator.h"
 #include "src/compiler/js-generic-lowering.h"
 #include "src/compiler/js-graph.h"
 #include "src/compiler/machine-operator.h"
@@ skipping 588 matching lines @@
   Node* frame_state = NodeProperties::GetFrameStateInput(node, 0);
 
   // Get the set of properties to enumerate.
   Runtime::Function const* function =
       Runtime::FunctionForId(Runtime::kGetPropertyNamesFast);
   CallDescriptor const* descriptor = Linkage::GetRuntimeCallDescriptor(
       zone(), function->function_id, 1, Operator::kNoProperties);
   Node* cache_type = effect = graph()->NewNode(
       common()->Call(descriptor),
       jsgraph()->CEntryStubConstant(function->result_size), object,
-      jsgraph()->ExternalConstant(
-          ExternalReference(function->function_id, isolate())),
+      jsgraph()->ExternalConstant(function->function_id),
       jsgraph()->Int32Constant(1), context, frame_state, effect, control);
   control = graph()->NewNode(common()->IfSuccess(), cache_type);
 
   Node* object_map = effect = graph()->NewNode(
       machine()->Load(kMachAnyTagged), object,
       jsgraph()->IntPtrConstant(HeapObject::kMapOffset - kHeapObjectTag),
       effect, control);
   Node* cache_type_map = effect = graph()->NewNode(
       machine()->Load(kMachAnyTagged), cache_type,
       jsgraph()->IntPtrConstant(HeapObject::kMapOffset - kHeapObjectTag),
@@ skipping 210 matching lines @@
 }
 
 
 MachineOperatorBuilder* JSGenericLowering::machine() const {
   return jsgraph()->machine();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8