[turbofan] Don't create handle in JSHeapBroker::native_context.

Instead, remember the canonical handle during SerializeStandardObjects.

Bug: v8:7790
Change-Id: Id57d861e92088fbc64c05fbee1612376000c06c9
Reviewed-on: https://chromium-review.googlesource.com/1233494Reviewed-by: Maya Lekova <mslekova@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56029}

src/compiler/js-create-lowering.h

@@ -33,13 +33,11 @@ class V8_EXPORT_PRIVATE JSCreateLowering final
     : public NON_EXPORTED_BASE(AdvancedReducer) {
  public:
   JSCreateLowering(Editor* editor, CompilationDependencies* dependencies,
-                   JSGraph* jsgraph, JSHeapBroker* js_heap_broker,
-                   Handle<Context> native_context, Zone* zone)
+                   JSGraph* jsgraph, JSHeapBroker* js_heap_broker, Zone* zone)
       : AdvancedReducer(editor),
         dependencies_(dependencies),
         jsgraph_(jsgraph),
         js_heap_broker_(js_heap_broker),
-        native_context_(native_context),
         zone_(zone) {}
   ~JSCreateLowering() final = default;
 
@@ -116,8 +114,7 @@ class V8_EXPORT_PRIVATE JSCreateLowering final
   Graph* graph() const;
   JSGraph* jsgraph() const { return jsgraph_; }
   Isolate* isolate() const;
-  Handle<Context> native_context() const { return native_context_; }
-  NativeContextRef native_context_ref() const;
+  NativeContextRef native_context() const;
   CommonOperatorBuilder* common() const;
   SimplifiedOperatorBuilder* simplified() const;
   CompilationDependencies* dependencies() const { return dependencies_; }
@@ -127,7 +124,6 @@ class V8_EXPORT_PRIVATE JSCreateLowering final
   CompilationDependencies* const dependencies_;
   JSGraph* const jsgraph_;
   JSHeapBroker* const js_heap_broker_;
-  Handle<Context> const native_context_;
   Zone* const zone_;
 };
 

src/compiler/js-heap-broker.cc

@@ -1219,6 +1219,11 @@ bool JSHeapBroker::SerializingAllowed() const {
 }
 
 void JSHeapBroker::SerializeStandardObjects() {
+  if (!native_context_.has_value()) {
+    native_context_ = NativeContextRef(this, isolate()->native_context());
+    native_context_->Serialize();
+  }
+
   if (mode() == kDisabled) return;
 
   Trace("Serializing standard objects.\n");
@@ -1332,8 +1337,6 @@ void JSHeapBroker::SerializeStandardObjects() {
     }
   }
 
-  GetOrCreateData(isolate()->native_context())->AsNativeContext()->Serialize();
-
   Trace("Finished serializing standard objects.\n");
 }
 
@@ -1397,11 +1400,6 @@ int ObjectRef::AsSmi() const {
   return object<Smi>()->value();
 }
 
-NativeContextRef JSHeapBroker::native_context() {
-  AllowHandleAllocation handle_allocation;
-  return NativeContextRef(this, isolate()->native_context());
-}
-
 base::Optional<MapRef> JSObjectRef::GetObjectCreateMap() const {
   if (broker()->mode() == JSHeapBroker::kDisabled) {
     AllowHandleAllocation handle_allocation;
@@ -2120,6 +2118,12 @@ void ContextRef::Serialize() {
   data()->AsContext()->Serialize();
 }
 
+void NativeContextRef::Serialize() {
+  if (broker()->mode() == JSHeapBroker::kDisabled) return;
+  CHECK_EQ(broker()->mode(), JSHeapBroker::kSerializing);
+  data()->AsNativeContext()->Serialize();
+}
+
 #undef BIMODAL_ACCESSOR
 #undef BIMODAL_ACCESSOR_B
 #undef BIMODAL_ACCESSOR_C

src/compiler/js-heap-broker.h

@@ -256,6 +256,7 @@ class ContextRef : public HeapObjectRef {
 class NativeContextRef : public ContextRef {
  public:
   using ContextRef::ContextRef;
+  void Serialize();
 
 #define DECL_ACCESSOR(type, name) type##Ref name() const;
   BROKER_NATIVE_CONTEXT_FIELDS(DECL_ACCESSOR)
@@ -468,8 +469,7 @@ class V8_EXPORT_PRIVATE JSHeapBroker : public NON_EXPORTED_BASE(ZoneObject) {
 
   Isolate* isolate() const { return isolate_; }
   Zone* zone() const { return zone_; }
-
-  NativeContextRef native_context();
+  NativeContextRef native_context() const { return native_context_.value(); }
 
   enum BrokerMode { kDisabled, kSerializing, kSerialized };
   BrokerMode mode() const { return mode_; }
@@ -497,6 +497,7 @@ class V8_EXPORT_PRIVATE JSHeapBroker : public NON_EXPORTED_BASE(ZoneObject) {
 
   Isolate* const isolate_;
   Zone* const zone_;
+  base::Optional<NativeContextRef> native_context_;
   ZoneUnorderedMap<Address, ObjectData*> refs_;
   BrokerMode mode_;
 };

src/compiler/pipeline.cc

@@ -1307,7 +1307,7 @@ struct TypedLoweringPhase {
                                               data->common(), temp_zone);
     JSCreateLowering create_lowering(&graph_reducer, data->dependencies(),
                                      data->jsgraph(), data->js_heap_broker(),
-                                     data->native_context(), temp_zone);
+                                     temp_zone);
     JSTypedLowering typed_lowering(&graph_reducer, data->jsgraph(),
                                    data->js_heap_broker(), temp_zone);
     ConstantFoldingReducer constant_folding_reducer(

test/unittests/compiler/js-create-lowering-unittest.cc

@@ -34,9 +34,7 @@ class JSCreateLoweringTest : public TypedGraphTest {
         javascript_(zone()),
         deps_(isolate(), zone()),
         handle_scope_(isolate()) {
-    if (FLAG_concurrent_compiler_frontend) {
-      js_heap_broker()->SerializeStandardObjects();
-    }
+    js_heap_broker()->SerializeStandardObjects();
   }
   ~JSCreateLoweringTest() override = default;
 
@@ -49,7 +47,7 @@ class JSCreateLoweringTest : public TypedGraphTest {
     // TODO(titzer): mock the GraphReducer here for better unit testing.
     GraphReducer graph_reducer(zone(), graph());
     JSCreateLowering reducer(&graph_reducer, &deps_, &jsgraph, js_heap_broker(),
-                             native_context(), zone());
+                             zone());
     return reducer.Reduce(node);
   }