[Atomics] code stubs for atomic operations

src/code-factory.h

Index: src/code-factory.h
diff --git a/src/code-factory.h b/src/code-factory.h
index 4dd9ecc80472716a13c3b43a24ae3e6b55004b40..7ed3bf554c668f0230643fe200c0457e81ba31fc 100644
--- a/src/code-factory.h
+++ b/src/code-factory.h
@@ -146,6 +146,8 @@ class CodeFactory final {
                                              TailCallMode tail_call_mode);
   static Callable InterpreterPushArgsAndConstruct(Isolate* isolate);
   static Callable InterpreterCEntry(Isolate* isolate, int result_size = 1);
+
+  static Callable AtomicsLoad(Isolate* isolate);
 };
 
 }  // namespace internal