Merge flush code phase into marking phase.

src/objects.h

 // Copyright 2006-2009 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 3353 matching lines @@
 
   // [code]: Function code.
   DECL_ACCESSORS(code, Code)
 
   // [scope_info]: Scope info.
   DECL_ACCESSORS(scope_info, SerializedScopeInfo)
 
   // [construct stub]: Code stub for constructing instances of this function.
   DECL_ACCESSORS(construct_stub, Code)
 
+  inline Code* unchecked_code();
+
   // Returns if this function has been compiled to native code yet.
   inline bool is_compiled();
 
   // [length]: The function length - usually the number of declared parameters.
   // Use up to 2^30 parameters.
   inline int length();
   inline void set_length(int value);
 
   // [formal parameter count]: The declared number of parameters.
   inline int formal_parameter_count();
@@ skipping 87 matching lines @@
 
   inline bool try_full_codegen();
   inline void set_try_full_codegen(bool flag);
 
   // Indicates if this function can be lazy compiled.
   // This is used to determine if we can safely flush code from a function
   // when doing GC if we expect that the function will no longer be used.
   inline bool allows_lazy_compilation();
   inline void set_allows_lazy_compilation(bool flag);
 
+  // Indicates how many full GCs this function has survived with assigned
+  // code object. Used to determine when it is relatively safe to flush
+  // this code object and replace it with lazy compilation stub.
+  // Age is reset when GC notices that the code object is referenced
+  // from the stack or compilation cache.
+  inline int code_age();
+  inline void set_code_age(int age);
+
+
   // Check whether a inlined constructor can be generated with the given
   // prototype.
   bool CanGenerateInlineConstructor(Object* prototype);
 
   // For functions which only contains this property assignments this provides
   // access to the names for the properties assigned.
   DECL_ACCESSORS(this_property_assignments, Object)
   inline int this_property_assignments_count();
   inline void set_this_property_assignments_count(int value);
   String* GetThisPropertyAssignmentName(int index);
@@ skipping 110 matching lines @@
   // the start_position_and_type field.
   static const int kIsExpressionBit = 0;
   static const int kIsTopLevelBit   = 1;
   static const int kStartPositionShift = 2;
   static const int kStartPositionMask = ~((1 << kStartPositionShift) - 1);
 
   // Bit positions in compiler_hints.
   static const int kHasOnlySimpleThisPropertyAssignments = 0;
   static const int kTryFullCodegen = 1;
   static const int kAllowLazyCompilation = 2;
+  static const int kCodeAgeShift = 3;
+  static const int kCodeAgeMask = 7;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(SharedFunctionInfo);
 };
 
 
 // JSFunction describes JavaScript functions.
 class JSFunction: public JSObject {
  public:
   // [prototype_or_initial_map]:
   DECL_ACCESSORS(prototype_or_initial_map, Object)
 
   // [shared_function_info]: The information about the function that
   // can be shared by instances.
   DECL_ACCESSORS(shared, SharedFunctionInfo)
 
+  inline SharedFunctionInfo* unchecked_shared();
+
   // [context]: The context for this function.
   inline Context* context();
   inline Object* unchecked_context();
   inline void set_context(Object* context);
 
   // [code]: The generated code object for this function.  Executed
   // when the function is invoked, e.g. foo() or new foo(). See
   // [[Call]] and [[Construct]] description in ECMA-262, section
   // 8.6.2, page 27.
   inline Code* code();
   inline void set_code(Code* value);
 
+  inline Code* unchecked_code();
+
   // Tells whether this function is builtin.
   inline bool IsBuiltin();
 
   // [literals]: Fixed array holding the materialized literals.
   //
   // If the function contains object, regexp or array literals, the
   // literals array prefix contains the object, regexp, and array
   // function to be used when creating these literals.  This is
   // necessary so that we do not dynamically lookup the object, regexp
   // or array functions.  Performing a dynamic lookup, we might end up
@@ skipping 1834 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_