[es6] Tail calls support.

src/compiler/ast-graph-builder.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/compiler/ast-graph-builder.h"
 
 #include "src/ast/scopes.h"
 #include "src/compiler.h"
 #include "src/compiler/ast-loop-assignment-analyzer.h"
 #include "src/compiler/control-builders.h"
@@ skipping 2459 matching lines @@
         NewNode(op, callee, source, function, language, position);
     PrepareFrameState(new_callee, expr->EvalId(),
                       OutputFrameStateCombine::PokeAt(arg_count + 1));
 
     // Patch callee on the environment.
     environment()->Poke(arg_count + 1, new_callee);
   }
 
   // Create node to perform the function call.
   VectorSlotPair feedback = CreateVectorSlotPair(expr->CallFeedbackICSlot());
-  const Operator* call = javascript()->CallFunction(
-      args->length() + 2, language_mode(), feedback, receiver_hint);
+  const Operator* call =
+      javascript()->CallFunction(args->length() + 2, language_mode(), feedback,
+                                 receiver_hint, expr->tail_call_mode());
   FrameStateBeforeAndAfter states(this, expr->CallId());
   Node* value = ProcessArguments(call, args->length() + 2);
   environment()->Push(value->InputAt(0));  // The callee passed to the call.
   states.AddToNode(value, expr->ReturnId(), OutputFrameStateCombine::Push());
   environment()->Drop(1);
   ast_context()->ProduceValue(value);
 }
 
 
 void AstGraphBuilder::VisitCallSuper(Call* expr) {
@@ skipping 1847 matching lines @@
     // Phi does not exist yet, introduce one.
     value = NewPhi(inputs, value, control);
     value->ReplaceInput(inputs - 1, other);
   }
   return value;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8