v8/test/mjsunit/regress/regress-crbug-937734.js

// 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.

// Flags: --allow-natives-syntax --opt

function foo()
{
    return 1 in [0];
}

%PrepareFunctionForOptimization(foo);
foo();
foo();
%OptimizeFunctionOnNextCall(foo);
foo();
assertOptimized(foo);