[turbofan] Use reference equal to zero instead of a smi check.

src/compiler/js-typed-lowering.cc

Index: src/compiler/js-typed-lowering.cc
diff --git a/src/compiler/js-typed-lowering.cc b/src/compiler/js-typed-lowering.cc
index fb59ce06192cf33d5d8ca69c668defd2824cd333..0f6f38cb0f38f120163956faf008373631c0b6d1 100644
--- a/src/compiler/js-typed-lowering.cc
+++ b/src/compiler/js-typed-lowering.cc
@@ -942,7 +942,8 @@ Reduction JSTypedLowering::ReduceJSLoadDynamicGlobal(Node* node) {
     Node* load = graph()->NewNode(
         javascript()->LoadContext(depth, Context::EXTENSION_INDEX, false),
         context, context, effect);
-    Node* check = graph()->NewNode(simplified()->ObjectIsSmi(), load);
+    Node* check = graph()->NewNode(simplified()->ReferenceEqual(Type::Tagged()),
+                                   load, jsgraph()->ZeroConstant());
     Node* branch = graph()->NewNode(common()->Branch(BranchHint::kTrue), check,
                                     check_true);
     Node* if_true = graph()->NewNode(common()->IfTrue(), branch);