v8/test/mjsunit/compiler/js-create-arguments.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

class C extends Object {
  bla() {}
}

const bla = C.prototype.bla;

function bar(c) {
  %TurbofanStaticAssert(c.bla === bla);
}

function foo() {
  let c = new C(...arguments);
  bar(c);
}

%PrepareFunctionForOptimization(bar);
%PrepareFunctionForOptimization(C);
%PrepareFunctionForOptimization(main);
%PrepareFunctionForOptimization(foo);

bar({});
bar({a:1});
bar({aa:1});
bar({aaa:1});
bar({aaaa:1});
bar({aaaaa:1});

function main() {
  return foo(1,2,3);
};

main();
main();
%OptimizeFunctionForTopTier(main);
main();