Share optimized code for closures.

src/objects.h

 // Copyright 2012 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 5138 matching lines @@
 // SharedFunctionInfo describes the JSFunction information that can be
 // shared by multiple instances of the function.
 class SharedFunctionInfo: public HeapObject {
  public:
   // [name]: Function name.
   DECL_ACCESSORS(name, Object)
 
   // [code]: Function code.
   DECL_ACCESSORS(code, Code)
 
+  // [optimized_code_map]: Map from global context to optimized code
+  // and a shared literals array or Smi 0 if none.
+  DECL_ACCESSORS(optimized_code_map, Object)
+
+  // Returns index i of the entry with the specified context. At position
+  // i - 1 is the context, position i the code, and i + 1 the literals array.

[Michael Starzinger, 2012/05/23 11:16:29]

Can we add a comment about what happens when no entry is found?

[fschneider, 2012/06/14 11:08:23]

Done.

+  int SearchOptimizedCodeMap(Context* global_context);
+
   // [scope_info]: Scope info.
   DECL_ACCESSORS(scope_info, ScopeInfo)
 
   // [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();
@@ skipping 87 matching lines @@
   // Stores the initial map and installs the countdown stub.
   // IsInobjectSlackTrackingInProgress is normally true after this call,
   // except when tracking have not been started (e.g. the map has no unused
   // properties or the snapshot is being built).
   void StartInobjectSlackTracking(Map* map);
 
   // Completes the tracking.
   // IsInobjectSlackTrackingInProgress is false after this call.
   void CompleteInobjectSlackTracking();
 
+  // Invoked before pointers in SharedFunctionInfo are being marked.

[Michael Starzinger, 2012/05/23 11:16:29]

It would be nice to also have a short comment what this method does on top of
when it is being called.

[fschneider, 2012/06/14 11:08:23]

Done.

+  inline void BeforeVisitingPointers();
+
   // Clears the initial_map before the GC marking phase to ensure the reference
   // is weak. IsInobjectSlackTrackingInProgress is false after this call.
   void DetachInitialMap();
 
   // Restores the link to the initial map after the GC marking phase.
   // IsInobjectSlackTrackingInProgress is true after this call.
   void AttachInitialMap(Map* map);
 
   // False if there are definitely no live objects created from this function.
   // True if live objects _may_ exist (existence not guaranteed).
@@ skipping 240 matching lines @@
   // Casting.
   static inline SharedFunctionInfo* cast(Object* obj);
 
   // Constants.
   static const int kDontAdaptArgumentsSentinel = -1;
 
   // Layout description.
   // Pointer fields.
   static const int kNameOffset = HeapObject::kHeaderSize;
   static const int kCodeOffset = kNameOffset + kPointerSize;
-  static const int kScopeInfoOffset = kCodeOffset + kPointerSize;
+  static const int kOptimizedCodeMapOffset = kCodeOffset + kPointerSize;
+  static const int kScopeInfoOffset = kOptimizedCodeMapOffset + kPointerSize;
   static const int kConstructStubOffset = kScopeInfoOffset + kPointerSize;
   static const int kInstanceClassNameOffset =
       kConstructStubOffset + kPointerSize;
   static const int kFunctionDataOffset =
       kInstanceClassNameOffset + kPointerSize;
   static const int kScriptOffset = kFunctionDataOffset + kPointerSize;
   static const int kDebugInfoOffset = kScriptOffset + kPointerSize;
   static const int kInferredNameOffset = kDebugInfoOffset + kPointerSize;
   static const int kInitialMapOffset =
       kInferredNameOffset + kPointerSize;
@@ skipping 3123 matching lines @@
     } else {
       value &= ~(1 << bit_position);
     }
     return value;
   }
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_H_