[Interpreter] Enable assignments in expressions.

src/compiler/bytecode-graph-builder.cc

Index: src/compiler/bytecode-graph-builder.cc
diff --git a/src/compiler/bytecode-graph-builder.cc b/src/compiler/bytecode-graph-builder.cc
index eff5fd0cfa895258aba70718746c54754725e224..55b91f90a86056dad7b59aaec0ec772a136acc5b 100644
--- a/src/compiler/bytecode-graph-builder.cc
+++ b/src/compiler/bytecode-graph-builder.cc
@@ -309,6 +309,13 @@ void BytecodeGraphBuilder::VisitStar(
 }
 
 
+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) {