[ext-code-space] Support background compilation

Bug: v8:11880
Change-Id: I557c4d6f83bc3203c115824e26fcb2ecf0473e1a
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3308796
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Dominik Inführ <dinfuehr@chromium.org>
Auto-Submit: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Dominik Inführ <dinfuehr@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78155}

src/heap/factory-base.cc

@@ -81,7 +81,10 @@ Handle<CodeDataContainer> FactoryBase<Impl>::NewCodeDataContainer(
                                     SKIP_WRITE_BARRIER);
   data_container.set_kind_specific_flags(flags, kRelaxedStore);
   if (V8_EXTERNAL_CODE_SPACE_BOOL) {
-    impl()->SetExternalCodeSpaceInDataContainer(data_container);
+    Isolate* isolate_for_heap_sandbox = impl()->isolate_for_heap_sandbox();
+    data_container.AllocateExternalPointerEntries(isolate_for_heap_sandbox);
+    data_container.set_raw_code(Smi::zero(), SKIP_WRITE_BARRIER);
+    data_container.set_code_entry_point(isolate_for_heap_sandbox, kNullAddress);
   }
   data_container.clear_padding();
   return handle(data_container, isolate());

src/heap/factory.cc

@@ -1371,14 +1371,6 @@ void Factory::AddToScriptList(Handle<Script> script) {
   isolate()->heap()->set_script_list(*scripts);
 }
 
-void Factory::SetExternalCodeSpaceInDataContainer(
-    CodeDataContainer data_container) {
-  DCHECK(V8_EXTERNAL_CODE_SPACE_BOOL);
-  data_container.AllocateExternalPointerEntries(isolate());
-  data_container.set_raw_code(Smi::zero(), SKIP_WRITE_BARRIER);
-  data_container.set_code_entry_point(isolate(), kNullAddress);
-}
-
 Handle<Script> Factory::CloneScript(Handle<Script> script) {
   Heap* heap = isolate()->heap();
   int script_id = isolate()->GetNextScriptId();

src/heap/factory.h

@@ -1001,12 +1001,22 @@ class V8_EXPORT_PRIVATE Factory : public FactoryBase<Factory> {
     // NOLINTNEXTLINE (google-readability-casting)
     return (Isolate*)this;  // NOLINT(readability/casting)
   }
+
+  // This is the real Isolate that will be used for allocating and accessing
+  // external pointer entries when V8_HEAP_SANDBOX is enabled.
+  Isolate* isolate_for_heap_sandbox() const {
+#ifdef V8_HEAP_SANDBOX
+    return isolate();
+#else
+    return nullptr;
+#endif  // V8_HEAP_SANDBOX
+  }
+
   bool CanAllocateInReadOnlySpace();
   bool EmptyStringRootIsInitialized();
   AllocationType AllocationTypeForInPlaceInternalizableString();
 
   void AddToScriptList(Handle<Script> shared);
-  void SetExternalCodeSpaceInDataContainer(CodeDataContainer data_container);
   // ------
 
   HeapObject AllocateRawWithAllocationSite(

src/heap/local-factory.h

@@ -66,19 +66,29 @@ class V8_EXPORT_PRIVATE LocalFactory : public FactoryBase<LocalFactory> {
     // NOLINTNEXTLINE (google-readability-casting)
     return (LocalIsolate*)this;  // NOLINT(readability/casting)
   }
+
+  // This is the real Isolate that will be used for allocating and accessing
+  // external pointer entries when V8_HEAP_SANDBOX is enabled.
+  Isolate* isolate_for_heap_sandbox() {
+#ifdef V8_HEAP_SANDBOX
+    return isolate_for_heap_sandbox_;
+#else
+    return nullptr;
+#endif  // V8_HEAP_SANDBOX
+  }
+
   inline bool CanAllocateInReadOnlySpace() { return false; }
   inline bool EmptyStringRootIsInitialized() { return true; }
   inline AllocationType AllocationTypeForInPlaceInternalizableString();
   // ------
 
   void AddToScriptList(Handle<Script> shared);
-
-  void SetExternalCodeSpaceInDataContainer(CodeDataContainer data_container) {
-    UNREACHABLE();
-  }
   // ------
 
   ReadOnlyRoots roots_;
+#ifdef V8_HEAP_SANDBOX
+  Isolate* isolate_for_heap_sandbox_;
+#endif
 #ifdef DEBUG
   bool a_script_was_added_to_the_script_list_ = false;
 #endif