FYI Implementing 'super' keyword

src/ast.h

Index: src/ast.h
diff --git a/src/ast.h b/src/ast.h
index e18fdc79c71ffad36d3af96e65389775b039b6c9..80075d90ab482e372b5489c53ac81567f841a73b 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -73,27 +73,28 @@ namespace internal {
   V(TryFinallyStatement)                        \
   V(DebuggerStatement)
 
-#define EXPRESSION_NODE_LIST(V)                 \
-  V(FunctionLiteral)                            \
-  V(NativeFunctionLiteral)                      \
-  V(Conditional)                                \
-  V(VariableProxy)                              \
-  V(Literal)                                    \
-  V(RegExpLiteral)                              \
-  V(ObjectLiteral)                              \
-  V(ArrayLiteral)                               \
-  V(Assignment)                                 \
-  V(Yield)                                      \
-  V(Throw)                                      \
-  V(Property)                                   \
-  V(Call)                                       \
-  V(CallNew)                                    \
-  V(CallRuntime)                                \
-  V(UnaryOperation)                             \
-  V(CountOperation)                             \
-  V(BinaryOperation)                            \
-  V(CompareOperation)                           \
-  V(ThisFunction)                               \
+#define EXPRESSION_NODE_LIST(V) \
+  V(FunctionLiteral)            \
+  V(NativeFunctionLiteral)      \
+  V(Conditional)                \
+  V(VariableProxy)              \
+  V(Literal)                    \
+  V(RegExpLiteral)              \
+  V(ObjectLiteral)              \
+  V(ArrayLiteral)               \
+  V(Assignment)                 \
+  V(Yield)                      \
+  V(Throw)                      \
+  V(Property)                   \
+  V(Call)                       \
+  V(CallNew)                    \
+  V(CallRuntime)                \
+  V(UnaryOperation)             \
+  V(CountOperation)             \
+  V(BinaryOperation)            \
+  V(CompareOperation)           \
+  V(ThisFunction)               \
+  V(SuperReference)             \
   V(CaseClause)
 
 #define AST_NODE_LIST(V)                        \
@@ -1710,6 +1711,10 @@ class Property V8_FINAL : public Expression, public FeedbackSlotInterface {
   void mark_for_call() { is_for_call_ = true; }
   bool IsForCall() { return is_for_call_; }
 
+  bool IsSuperAccess() {
+    return obj()->IsSuperReference();
+  }
+
   TypeFeedbackId PropertyFeedbackId() { return reuse(id()); }
 
   virtual int ComputeFeedbackSlotCount() { return FLAG_vector_ics ? 1 : 0; }
@@ -2554,6 +2559,24 @@ class ThisFunction V8_FINAL : public Expression {
   explicit ThisFunction(Zone* zone, int pos): Expression(zone, pos) {}
 };
 
+
+class SuperReference V8_FINAL : public Expression {
+ public:
+  DECLARE_NODE_TYPE(SuperReference)
+
+  VariableProxy* this_var() const { return this_var_; }
+
+  TypeFeedbackId HomeObjectFeedbackId() { return reuse(id()); }
+ protected:
+  explicit SuperReference(Zone* zone, VariableProxy* this_var, int pos)
+      : Expression(zone, pos), this_var_(this_var) {
+      DCHECK(this_var->is_this());
+  }
+
+  VariableProxy* this_var_;
+};
+
+
 #undef DECLARE_NODE_TYPE
 
 
@@ -3472,6 +3495,11 @@ class AstNodeFactory V8_FINAL BASE_EMBEDDED {
     VISIT_AND_RETURN(ThisFunction, fun)
   }
 
+  SuperReference* NewSuperReference(VariableProxy* this_var, int pos) {
+    SuperReference* super = new (zone_) SuperReference(zone_, this_var, pos);
+    VISIT_AND_RETURN(SuperReference, super);
+  }
+
 #undef VISIT_AND_RETURN
 
  private: