[turbofan] Use FastNewClosureStub if possible.

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 396 matching lines @@
                             graph()->start()));
   }
   node->ReplaceInput(2, NodeProperties::GetValueInput(node, 1));
   node->ReplaceInput(1, jsgraph()->Int32Constant(Context::SlotOffset(
                             static_cast<int>(access.index()))));
   node->set_op(
       machine()->Store(StoreRepresentation(kMachAnyTagged, kFullWriteBarrier)));
 }
 
 
+void JSGenericLowering::LowerJSCreateClosure(Node* node) {
+  CreateClosureParameters p = CreateClosureParametersOf(node->op());
+  node->InsertInput(zone(), 1, jsgraph()->HeapConstant(p.shared_info()));
+  node->InsertInput(zone(), 2, jsgraph()->BooleanConstant(p.pretenure()));
+  ReplaceWithRuntimeCall(node, Runtime::kNewClosure);
+}
+
+
 void JSGenericLowering::LowerJSCreateCatchContext(Node* node) {
   Unique<String> name = OpParameter<Unique<String>>(node);
   node->InsertInput(zone(), 0, jsgraph()->HeapConstant(name));
   ReplaceWithRuntimeCall(node, Runtime::kPushCatchContext);
 }
 
 
 void JSGenericLowering::LowerJSCallConstruct(Node* node) {
   int arity = OpParameter<int>(node);
   CallConstructStub stub(isolate(), NO_CALL_CONSTRUCTOR_FLAGS);
@@ skipping 121 matching lines @@
 }
 
 
 MachineOperatorBuilder* JSGenericLowering::machine() const {
   return jsgraph()->machine();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8