Improve memory usage of receiver type feedback.

src/type-info.h

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 185 matching lines @@
 
 
 enum StringStubFeedback {
   DEFAULT_STRING_STUB = 0,
   STRING_INDEX_OUT_OF_BOUNDS = 1
 };
 
 
 // Forward declarations.
 class Assignment;
-class UnaryOperation;
 class BinaryOperation;
 class Call;
+class CaseClause;
 class CompareOperation;
+class CompilationInfo;
 class CountOperation;
-class CompilationInfo;
 class Property;
-class CaseClause;
+class SmallMapList;
+class UnaryOperation;
+
 
 class TypeFeedbackOracle BASE_EMBEDDED {
  public:
   TypeFeedbackOracle(Handle<Code> code, Handle<Context> global_context);
 
   bool LoadIsMonomorphicNormal(Property* expr);
   bool LoadIsMegamorphicWithTypeInfo(Property* expr);
   bool StoreIsMonomorphicNormal(Expression* expr);
   bool StoreIsMegamorphicWithTypeInfo(Expression* expr);
   bool CallIsMonomorphic(Call* expr);
 
   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);
 
   bool LoadIsBuiltin(Property* expr, Builtins::Name id);
 
   // TODO(1571) We can't use ToBooleanStub::Types as the return value because
   // of various cylces in our headers. Death to tons of implementations in
   // headers!! :-P
   byte ToBooleanTypes(unsigned ast_id);
 
   // Get type information for arithmetic operations and compares.
   TypeInfo UnaryType(UnaryOperation* expr);
   TypeInfo BinaryType(BinaryOperation* expr);
   TypeInfo CompareType(CompareOperation* expr);
   bool IsSymbolCompare(CompareOperation* expr);
   TypeInfo SwitchType(CaseClause* clause);
   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);
 
   void BuildDictionary(Handle<Code> code);
   void GetRelocInfos(Handle<Code> code, ZoneList<RelocInfo>* infos);
   void CreateDictionary(Handle<Code> code, ZoneList<RelocInfo>* infos);
   void RelocateRelocInfos(ZoneList<RelocInfo>* infos,
                           byte* old_start,
                           byte* new_start);
   void ProcessRelocInfos(ZoneList<RelocInfo>* infos);
   void ProcessTarget(unsigned ast_id, Code* target);
 
   // Returns an element from the backing store. Returns undefined if
   // there is no information.
   Handle<Object> GetInfo(unsigned ast_id);
 
   Handle<Context> global_context_;
   Handle<NumberDictionary> dictionary_;
 
   DISALLOW_COPY_AND_ASSIGN(TypeFeedbackOracle);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_TYPE_INFO_H_