Basic TurboFan support for rest arguments.

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 445 matching lines @@
 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);
       break;
     case CreateArgumentsParameters::kRestArray:
-      UNIMPLEMENTED();
+      node->InsertInput(zone(), 1, jsgraph()->Constant(p.start_index()));
+      ReplaceWithRuntimeCall(node, Runtime::kNewRestArguments_Generic);
       break;
   }
 }
 
 
 void JSGenericLowering::LowerJSCreateArray(Node* node) {
   CreateArrayParameters const& p = CreateArrayParametersOf(node->op());
   int const arity = static_cast<int>(p.arity());
   Node* new_target = node->InputAt(1);
   // TODO(turbofan): We embed the AllocationSite from the Operator at this
@@ skipping 393 matching lines @@
 }
 
 
 MachineOperatorBuilder* JSGenericLowering::machine() const {
   return jsgraph()->machine();
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8