[Interpreter] Enable assignments in expressions.

src/compiler/bytecode-graph-builder.cc

 // Copyright 2015 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/bytecode-graph-builder.h"
 
 #include "src/compiler/linkage.h"
 #include "src/compiler/operator-properties.h"
 #include "src/interpreter/bytecode-array-iterator.h"
 
@@ skipping 291 matching lines @@
 }
 
 
 void BytecodeGraphBuilder::VisitStar(
     const interpreter::BytecodeArrayIterator& iterator) {
   Node* value = environment()->LookupAccumulator();
   environment()->BindRegister(iterator.GetRegisterOperand(0), value);
 }
 
 
+void BytecodeGraphBuilder::VisitMov(
+    const interpreter::BytecodeArrayIterator& iterator) {
+  Node* value = environment()->LookupRegister(iterator.GetRegisterOperand(0));
+  environment()->BindRegister(iterator.GetRegisterOperand(1), value);
+}
+
+
 void BytecodeGraphBuilder::BuildLoadGlobal(
     const interpreter::BytecodeArrayIterator& iterator,
     TypeofMode typeof_mode) {
   Handle<Name> name =
       Handle<Name>::cast(iterator.GetConstantForIndexOperand(0));
   VectorSlotPair feedback = CreateVectorSlotPair(iterator.GetIndexOperand(1));
 
   const Operator* op = javascript()->LoadGlobal(name, feedback, typeof_mode);
   Node* node = NewNode(op, BuildLoadFeedbackVector());
   AddEmptyFrameStateInputs(node);
@@ skipping 820 matching lines @@
 
 void BytecodeGraphBuilder::UpdateControlDependencyToLeaveFunction(Node* exit) {
   if (environment()->IsMarkedAsUnreachable()) return;
   environment()->MarkAsUnreachable();
   exit_controls_.push_back(exit);
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8