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diff --git a/deps/v8/test/mjsunit/es6/iterator-eager-deopt.js b/deps/v8/test/mjsunit/es6/iterator-eager-deopt.js
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+++ b/deps/v8/test/mjsunit/es6/iterator-eager-deopt.js
@@ -0,0 +1,69 @@
+// Copyright 2019 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.
+
+// The GetIterator bytecode is used to implement a part of the iterator
+// protocol (https://tc39.es/ecma262/#sec-getiterator). Here, the
+// bytecode performs multiple operations including some that have side-effects
+// and may deoptimize eagerly or lazily.
+// This test ensures the eager deoptimization is handled correctly.
+
+// Flags: --allow-natives-syntax --no-always-opt
+
+var getIteratorCount = 0;
+var iteratorCount = 0;
+var iteratorAfterEagerDeoptCount = 0;
+
+function foo(obj) {
+    // The following for-of loop uses the iterator protocol to iterate
+    // over the 'obj'.
+    // The GetIterator bytecode invovlves 3 steps:
+    // 1. method = GetMethod(obj, @@iterator)
+    // 2. iterator = Call(method, obj)
+    // 3. if(!IsJSReceiver(iterator)) throw SymbolIteratorInvalid.
+    for(var x of obj){}
+}
+
+// This iterator gets inlined when the 'foo' function is JIT compiled for
+// the first time.
+var iterator = function() {
+    iteratorCount++;
+    return {
+        next: function() {
+            return { done: true };
+        }
+    }
+}
+
+var iteratorAfterEagerDeopt = function() {
+    iteratorAfterEagerDeoptCount++;
+    return {
+        next: function() {
+            return { done: true };
+        }
+    }
+}
+
+// Here, retrieval of function at @@iterator has side effect (increments the
+// 'getIteratorCount'). Changing the value of 'iterator' in the JIT compiled
+// 'foo' causes deoptimization after the count is incremented. Now the deopt
+// cannot resume at the beginning of the bytecode because it would end up in
+// incrementing the count again.
+let y = { get [Symbol.iterator] () {
+            getIteratorCount++;
+            return iterator;
+         }
+    };
+
+%PrepareFunctionForOptimization(foo);
+foo(y);
+foo(y);
+%OptimizeFunctionOnNextCall(foo);
+
+// Change the value of 'iterator' to trigger eager deoptimization of 'foo'.
+iterator = iteratorAfterEagerDeopt
+foo(y);
+assertUnoptimized(foo);
+assertEquals(getIteratorCount, 3);
+assertEquals(iteratorCount, 2);
+assertEquals(iteratorAfterEagerDeoptCount, 1);