[es6] Tail calls support.

src/crankshaft/x64/lithium-codegen-x64.cc

 // Copyright 2013 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_X64
 
 #include "src/crankshaft/x64/lithium-codegen-x64.h"
 
 #include "src/base/bits.h"
 #include "src/code-factory.h"
@@ skipping 3742 matching lines @@
     DCHECK(slot_register.is(rdx));
     DCHECK(vector_register.is(rbx));
 
     AllowDeferredHandleDereference vector_structure_check;
     Handle<TypeFeedbackVector> vector = instr->hydrogen()->feedback_vector();
     int index = vector->GetIndex(instr->hydrogen()->slot());
 
     __ Move(vector_register, vector);
     __ Move(slot_register, Smi::FromInt(index));
 
+    // TODO(ishell): propagate correct TailCallMode
     Handle<Code> ic =
         CodeFactory::CallICInOptimizedCode(isolate(), arity, mode).code();
     CallCode(ic, RelocInfo::CODE_TARGET, instr);
   } else {
     __ Set(rax, arity);
     CallCode(isolate()->builtins()->Call(mode), RelocInfo::CODE_TARGET, instr);
   }
 }
 
 
@@ skipping 1889 matching lines @@
   RecordSafepoint(Safepoint::kNoLazyDeopt);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X64