diff --git a/test_ecma_bcopt/test_bytecode_optimizer_for_js.js b/test_ecma_bcopt/test_bytecode_optimizer_for_js.js
new file mode 100755
index 0000000000000000000000000000000000000000..b09c563761b94973ecf90dd5f5f68f1f2b0ce734
--- /dev/null
+++ b/test_ecma_bcopt/test_bytecode_optimizer_for_js.js
@@ -0,0 +1,3 @@
+let a = [1];
+a[0] = 2;
+
diff --git a/test_ecma_bcopt/test_bytecode_optimizer_for_js.txt b/test_ecma_bcopt/test_bytecode_optimizer_for_js.txt
new file mode 100755
index 0000000000000000000000000000000000000000..68a79ec1e82b065356e2b799fd26d928e9a1b3be
--- /dev/null
+++ b/test_ecma_bcopt/test_bytecode_optimizer_for_js.txt
@@ -0,0 +1,35 @@
+#
+# source binary: test_bytecode_optimizer_for_js.abc
+#
+
+.language ECMAScript
+
+# ====================
+# LITERALS
+
+
+# ====================
+# RECORDS
+
+.record _ESTypeAnnotation <external>
+
+.record _ESModuleMode {
+	u8 isModule
+}
+
+.record _ESCallTypeAnnotation <external>
+
+# ====================
+# METHODS
+
+.function any func_main_0_any_any_any_any_(any a0, any a1, any a2) <static> {
+	ecma.ldlexenvdyn
+	ecma.createarraywithbuffer 0x0
+	ecma.stlettoglobalrecord "a"
+	ecma.tryldglobalbyname "a"
+	sta.dyn v0
+	ldai.dyn 0x2
+	ecma.stobjbyindex v0, 0x0
+	ecma.returnundefined
+}
+