[modules] Don't unnecessarily keep function alive after evaluation.

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index 6ea36440b69055a2f603e9e67154889a6467f65e..a6d5035806268bf531bb6245fa4a7bcc814bb511 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -5713,17 +5713,26 @@ ACCESSORS(Module, code, Object, kCodeOffset)
 ACCESSORS(Module, exports, ObjectHashTable, kExportsOffset)
 ACCESSORS(Module, module_namespace, HeapObject, kModuleNamespaceOffset)
 ACCESSORS(Module, requested_modules, FixedArray, kRequestedModulesOffset)
-SMI_ACCESSORS(Module, flags, kFlagsOffset)
-BOOL_ACCESSORS(Module, flags, evaluated, kEvaluatedBit)
 ACCESSORS(Module, embedder_data, Object, kEmbedderDataOffset)
 SMI_ACCESSORS(Module, hash, kHashOffset)
 
 SharedFunctionInfo* Module::shared() const {
+  DCHECK(!evaluated());

[adamk, 2016/10/11 15:54:05]

I think I'd prefer killing this method and inlining any callers than leaving it
here, it seems dangerous now.

   return code()->IsSharedFunctionInfo() ? SharedFunctionInfo::cast(code())
                                         : JSFunction::cast(code())->shared();
 }
 
+bool Module::evaluated() const { return code()->IsModuleInfo(); }
+
+void Module::set_evaluated() {
+  DCHECK(!evaluated());
+  return set_code(shared()->scope_info()->ModuleDescriptorInfo());
+}
+
+bool Module::instantiated() const { return !code()->IsSharedFunctionInfo(); }
+
 ModuleInfo* Module::info() const {
+  if (evaluated()) return ModuleInfo::cast(code());
   return shared()->scope_info()->ModuleDescriptorInfo();
 }