v8/test/mjsunit/regress/regress-crbug-621868.js

// Copyright 2016 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 --verify-heap

function f(a) {  // First parameter is tagged.
  var n = 1 + a;
}

function g() {
  f();
  var d = {x: f()};
  return [d];
};
%PrepareFunctionForOptimization(g);
g();
g();
%OptimizeFunctionOnNextCall(g);
g();