Improve memory usage of receiver type feedback.

src/type-info.h

Index: src/type-info.h
diff --git a/src/type-info.h b/src/type-info.h
index dee4c34c929453e16d2f081927967ba171acf0fe..448e4c94e7ef9d6e2c334f90a7ff43b675e51020 100644
--- a/src/type-info.h
+++ b/src/type-info.h
@@ -203,14 +203,16 @@ enum StringStubFeedback {
 
 // Forward declarations.
 class Assignment;
-class UnaryOperation;
 class BinaryOperation;
 class Call;
+class CaseClause;
 class CompareOperation;
-class CountOperation;
 class CompilationInfo;
+class CountOperation;
 class Property;
-class CaseClause;
+class SmallMapList;
+class UnaryOperation;
+
 
 class TypeFeedbackOracle BASE_EMBEDDED {
  public:
@@ -225,13 +227,18 @@ class TypeFeedbackOracle BASE_EMBEDDED {
   Handle<Map> LoadMonomorphicReceiverType(Property* expr);
   Handle<Map> StoreMonomorphicReceiverType(Expression* expr);
 
-  ZoneMapList* LoadReceiverTypes(Property* expr, Handle<String> name);
-  ZoneMapList* StoreReceiverTypes(Assignment* expr, Handle<String> name);
-  ZoneMapList* CallReceiverTypes(Call* expr,
-                                 Handle<String> name,
-                                 CallKind call_kind);
+  void LoadReceiverTypes(Property* expr,
+                         Handle<String> name,
+                         SmallMapList* types);
+  void StoreReceiverTypes(Assignment* expr,
+                          Handle<String> name,
+                          SmallMapList* types);
+  void CallReceiverTypes(Call* expr,
+                         Handle<String> name,
+                         CallKind call_kind,
+                         SmallMapList* types);
   void CollectKeyedReceiverTypes(unsigned ast_id,
-                                 ZoneMapList* types);
+                                 SmallMapList* types);
 
   CheckType GetCallCheckType(Call* expr);
   Handle<JSObject> GetPrototypeForPrimitiveCheck(CheckType check);
@@ -252,9 +259,10 @@ class TypeFeedbackOracle BASE_EMBEDDED {
   TypeInfo IncrementType(CountOperation* expr);
 
  private:
-  ZoneMapList* CollectReceiverTypes(unsigned ast_id,
-                                    Handle<String> name,
-                                    Code::Flags flags);
+  void CollectReceiverTypes(unsigned ast_id,
+                            Handle<String> name,
+                            Code::Flags flags,
+                            SmallMapList* types);
 
   void SetInfo(unsigned ast_id, Object* target);