[turbofan] Initial support for constructor call inlining.

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 438 matching lines @@
           : Runtime::kLoadLookupSlotNoReferenceError;
   Node* projection = graph()->NewNode(common()->Projection(0), node);
   NodeProperties::ReplaceUses(node, projection, node, node, node);
   node->RemoveInput(NodeProperties::FirstValueIndex(node));
   node->InsertInput(zone(), 1, jsgraph()->Constant(access.name()));
   ReplaceWithRuntimeCall(node, function_id);
   projection->ReplaceInput(0, node);
 }
 
 
-void JSGenericLowering::LowerJSCreate(Node* node) { UNIMPLEMENTED(); }
+void JSGenericLowering::LowerJSCreate(Node* node) {
+  // TODO(4544): The duplication of the constructor function is only valid if
+  // actual constructor and original constructor coincide. Fix this!
+  node->InsertInput(zone(), 1, node->InputAt(0));  // Duplicate constructor.
+  ReplaceWithRuntimeCall(node, Runtime::kNewObject);
+}
 
 
 void JSGenericLowering::LowerJSCreateArguments(Node* node) {
   const CreateArgumentsParameters& p = CreateArgumentsParametersOf(node->op());
   switch (p.type()) {
     case CreateArgumentsParameters::kMappedArguments:
       ReplaceWithRuntimeCall(node, Runtime::kNewSloppyArguments_Generic);
       break;
     case CreateArgumentsParameters::kUnmappedArguments:
       ReplaceWithRuntimeCall(node, Runtime::kNewStrictArguments_Generic);
@@ skipping 383 matching lines @@
 }
 
 
 MachineOperatorBuilder* JSGenericLowering::machine() const {
   return jsgraph()->machine();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8