1 files changed, 26 insertions, 0 deletions
diff --git a/deps/v8/test/mjsunit/compiler/deopt-array-prototype-lastindexof.js b/deps/v8/test/mjsunit/compiler/deopt-array-prototype-lastindexof.js
new file mode 100644
index 0000000000..d47926cd3d
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+++ b/deps/v8/test/mjsunit/compiler/deopt-array-prototype-lastindexof.js
@@ -0,0 +1,26 @@
+// Copyright 2018 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax --opt
+
+/* Test deopt behaviors when the prototype has elements */
+
+// lastIndexOf
+
+(function () {
+  var array = [,];
+
+  function lastIndexOf(val) {
+    return array.lastIndexOf(val);
+  }
+
+  lastIndexOf(6); lastIndexOf(6);
+
+  %OptimizeFunctionOnNextCall(lastIndexOf);
+  assertEquals(lastIndexOf(6), -1);
+
+  array.__proto__.push(6);
+  // deopt
+  assertEquals(lastIndexOf(6), 0);
+})();