Implement proper module linking.

src/contexts.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 172 matching lines @@
 //                function contexts, and non-NULL for 'with' contexts.
 //                Used to implement the 'with' statement.
 //
 // [ extension ]  A pointer to an extension JSObject, or NULL. Used to
 //                implement 'with' statements and dynamic declarations
 //                (through 'eval'). The object in a 'with' statement is
 //                stored in the extension slot of a 'with' context.
 //                Dynamically declared variables/functions are also added
 //                to lazily allocated extension object. Context::Lookup
 //                searches the extension object for properties.
+//                For block contexts, contains the respective ScopeInfo.
+//                For module contexts, points back to the respective JSModule.
 //
 // [ global    ]  A pointer to the global object. Provided for quick
 //                access to the global object from inside the code (since
 //                we always have a context pointer).
 //
 // In addition, function contexts may have statically allocated context slots
 // to store local variables/functions that are accessed from inner functions
 // (via static context addresses) or through 'eval' (dynamic context lookups).
 // Finally, the global context contains additional slots for fast access to
 // global properties.
 
 class Context: public FixedArray {
  public:
   // Conversions.
   static Context* cast(Object* context) {
     ASSERT(context->IsContext());
     return reinterpret_cast<Context*>(context);
   }
 
   // The default context slot layout; indices are FixedArray slot indices.
   enum {
     // These slots are in all contexts.
     CLOSURE_INDEX,
     PREVIOUS_INDEX,
     // The extension slot is used for either the global object (in global
     // contexts), eval extension object (function contexts), subject of with
     // (with contexts), or the variable name (catch contexts), the serialized
-    // scope info (block contexts).
+    // scope info (block contexts), or the module instance (module contexts).
     EXTENSION_INDEX,
     GLOBAL_INDEX,
     MIN_CONTEXT_SLOTS,
 
     // This slot holds the thrown value in catch contexts.
     THROWN_OBJECT_INDEX = MIN_CONTEXT_SLOTS,
 
     // These slots are only in global contexts.
     GLOBAL_PROXY_INDEX = MIN_CONTEXT_SLOTS,
     SECURITY_TOKEN_INDEX,
@@ skipping 65 matching lines @@
 
     FIRST_WEAK_SLOT = OPTIMIZED_FUNCTIONS_LIST
   };
 
   // Direct slot access.
   JSFunction* closure() { return JSFunction::cast(get(CLOSURE_INDEX)); }
   void set_closure(JSFunction* closure) { set(CLOSURE_INDEX, closure); }
 
   Context* previous() {
     Object* result = unchecked_previous();
-    ASSERT(IsBootstrappingOrContext(result));
+    ASSERT(IsBootstrappingOrValidParentContext(result, this));
     return reinterpret_cast<Context*>(result);
   }
   void set_previous(Context* context) { set(PREVIOUS_INDEX, context); }
 
   bool has_extension() { return extension() != NULL; }
   Object* extension() { return get(EXTENSION_INDEX); }
   void set_extension(Object* object) { set(EXTENSION_INDEX, object); }
 
+  JSModule* module() { return JSModule::cast(get(EXTENSION_INDEX)); }
+  void set_module(JSModule* module) { set(EXTENSION_INDEX, module); }
+
   // Get the context where var declarations will be hoisted to, which
   // may be the context itself.
   Context* declaration_context();
 
   GlobalObject* global() {
     Object* result = get(GLOBAL_INDEX);
     ASSERT(IsBootstrappingOrGlobalObject(result));
     return reinterpret_cast<GlobalObject*>(result);
   }
   void set_global(GlobalObject* global) { set(GLOBAL_INDEX, global); }
@@ skipping 94 matching lines @@
       kHeaderSize,
       kHeaderSize + FIRST_WEAK_SLOT * kPointerSize,
       kSize> MarkCompactBodyDescriptor;
 
  private:
   // Unchecked access to the slots.
   Object* unchecked_previous() { return get(PREVIOUS_INDEX); }
 
 #ifdef DEBUG
   // Bootstrapping-aware type checks.
-  static bool IsBootstrappingOrContext(Object* object);
+  static bool IsBootstrappingOrValidParentContext(Object* object, Context* kid);
   static bool IsBootstrappingOrGlobalObject(Object* object);
 #endif
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_CONTEXTS_H_