Implement rudimentary module linking.

src/scopes.cc

 // 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 1073 matching lines @@
 
 bool Scope::MustAllocateInContext(Variable* var) {
   // If var is accessed from an inner scope, or if there is a possibility
   // that it might be accessed from the current or an inner scope (through
   // an eval() call or a runtime with lookup), it must be allocated in the
   // context.
   //
   // Exceptions: temporary variables are never allocated in a context;
   // catch-bound variables are always allocated in a context.
   if (var->mode() == TEMPORARY) return false;
-  if (is_catch_scope() || is_block_scope()) return true;
+  if (is_catch_scope() || is_block_scope() || is_module_scope()) return true;
   return var->has_forced_context_allocation() ||
       scope_calls_eval_ ||
       inner_scope_calls_eval_ ||
       scope_contains_with_ ||
       var->is_global();
 }
 
 
 bool Scope::HasArgumentsParameter() {
   for (int i = 0; i < params_.length(); i++) {
@@ skipping 123 matching lines @@
   num_heap_slots_ = Context::MIN_CONTEXT_SLOTS;
 
   // Allocate variables for this scope.
   // Parameters must be allocated first, if any.
   if (is_function_scope()) AllocateParameterLocals();
   AllocateNonParameterLocals();
 
   // Force allocation of a context for this scope if necessary. For a 'with'
   // scope and for a function scope that makes an 'eval' call we need a context,
   // even if no local variables were statically allocated in the scope.
-  bool must_have_context = is_with_scope() ||
+  // Likewise for modules.
+  bool must_have_context = is_with_scope() || is_module_scope() ||
       (is_function_scope() && calls_eval());
 
   // If we didn't allocate any locals in the local context, then we only
   // need the minimal number of slots if we must have a context.
   if (num_heap_slots_ == Context::MIN_CONTEXT_SLOTS && !must_have_context) {
     num_heap_slots_ = 0;
   }
 
   // Allocation done.
   ASSERT(num_heap_slots_ == 0 || num_heap_slots_ >= Context::MIN_CONTEXT_SLOTS);
 }
 
 
 int Scope::StackLocalCount() const {
   return num_stack_slots() -
       (function_ != NULL && function_->proxy()->var()->IsStackLocal() ? 1 : 0);
 }
 
 
 int Scope::ContextLocalCount() const {
   if (num_heap_slots() == 0) return 0;
   return num_heap_slots() - Context::MIN_CONTEXT_SLOTS -
       (function_ != NULL && function_->proxy()->var()->IsContextSlot() ? 1 : 0);
 }
 
 } }  // namespace v8::internal