[compiler] Make SourceTextModule never-serialized

Bug: v8:7790
Change-Id: I9b4ae95e2caf23e6574d2b48ec8796fcf82cfcc9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2874656Reviewed-by: Santiago Aboy Solanes <solanes@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#74398}

src/compiler/heap-refs.cc

@@ -4002,7 +4002,7 @@ base::Optional<ObjectRef> JSArrayRef::GetOwnCowElement(
 }
 
 base::Optional<CellRef> SourceTextModuleRef::GetCell(int cell_index) const {
-  if (data_->should_access_heap() || broker()->is_concurrent_inlining()) {
+  if (data_->should_access_heap()) {
     return MakeRef(broker(), broker()->CanonicalPersistentHandle(
                                  object()->GetCell(cell_index)));
   }
@@ -4012,9 +4012,9 @@ base::Optional<CellRef> SourceTextModuleRef::GetCell(int cell_index) const {
   return CellRef(broker(), cell);
 }
 
-ObjectRef SourceTextModuleRef::import_meta() const {
+base::Optional<ObjectRef> SourceTextModuleRef::import_meta() const {
   if (data_->should_access_heap()) {
-    return MakeRef(
+    return TryMakeRef(
         broker(), broker()->CanonicalPersistentHandle(object()->import_meta()));
   }
   return ObjectRef(broker(),

src/compiler/heap-refs.h

@@ -131,7 +131,7 @@ enum class RefSerializationKind {
   V(RegExpBoilerplateDescription, RefSerializationKind::kNeverSerialized) \
   V(ScopeInfo, RefSerializationKind::kNeverSerialized)                    \
   V(SharedFunctionInfo, RefSerializationKind::kNeverSerialized)           \
-  V(SourceTextModule, RefSerializationKind::kSerialized)                  \
+  V(SourceTextModule, RefSerializationKind::kNeverSerialized)             \
   V(TemplateObjectDescription, RefSerializationKind::kNeverSerialized)    \
   /* Subtypes of Object */                                                \
   V(HeapObject, RefSerializationKind::kBackgroundSerialized)
@@ -975,7 +975,7 @@ class SourceTextModuleRef : public HeapObjectRef {
   void Serialize();
 
   base::Optional<CellRef> GetCell(int cell_index) const;
-  ObjectRef import_meta() const;
+  base::Optional<ObjectRef> import_meta() const;
 };
 
 class TemplateObjectDescriptionRef : public HeapObjectRef {

src/compiler/js-context-specialization.cc

@@ -259,17 +259,18 @@ Reduction JSContextSpecialization::ReduceJSGetImportMeta(Node* node) {
   ContextRef context = maybe_context.value();
   SourceTextModuleRef module =
       context.get(Context::EXTENSION_INDEX).value().AsSourceTextModule();
-  ObjectRef import_meta = module.import_meta();
-  if (import_meta.IsJSObject()) {
-    Node* import_meta_const = jsgraph()->Constant(import_meta);
-    ReplaceWithValue(node, import_meta_const);
-    return Changed(import_meta_const);
-  } else {
-    DCHECK(import_meta.IsTheHole());
+  base::Optional<ObjectRef> import_meta = module.import_meta();
+  if (!import_meta.has_value()) return NoChange();
+  if (!import_meta->IsJSObject()) {
+    DCHECK(import_meta->IsTheHole());
     // The import.meta object has not yet been created. Let JSGenericLowering
     // replace the operator with a runtime call.
     return NoChange();
   }
+
+  Node* import_meta_const = jsgraph()->Constant(*import_meta);
+  ReplaceWithValue(node, import_meta_const);
+  return Changed(import_meta_const);
 }
 
 Isolate* JSContextSpecialization::isolate() const {

src/compiler/js-heap-broker.h

@@ -571,7 +571,10 @@ template <class T,
 base::Optional<typename ref_traits<T>::ref_type> TryMakeRef(
     JSHeapBroker* broker, T object) {
   ObjectData* data = broker->TryGetOrCreateData(object);
-  if (data == nullptr) return {};
+  if (data == nullptr) {
+    TRACE_BROKER_MISSING(broker, "ObjectData for " << Brief(object));
+    return {};
+  }
   return {typename ref_traits<T>::ref_type(broker, data)};
 }
 
@@ -580,7 +583,10 @@ template <class T,
 base::Optional<typename ref_traits<T>::ref_type> TryMakeRef(
     JSHeapBroker* broker, Handle<T> object) {
   ObjectData* data = broker->TryGetOrCreateData(object);
-  if (data == nullptr) return {};
+  if (data == nullptr) {
+    TRACE_BROKER_MISSING(broker, "ObjectData for " << Brief(*object));
+    return {};
+  }
   return {typename ref_traits<T>::ref_type(broker, data)};
 }
 

src/objects/source-text-module.tq

@@ -29,7 +29,7 @@ extern class SourceTextModule extends Module {
   // The value of import.meta inside of this module.
   // Lazily initialized on first access. It's the hole before first access and
   // a JSObject afterwards.
-  import_meta: TheHole|JSObject;
+  @acquireRead @releaseWrite import_meta: TheHole|JSObject;
 
   // The first visited module of a cycle. For modules not in a cycle, this is
   // the module itself. It's the hole before the module state transitions to