using System;
using System.Linq;
using System.Collections.Generic;
using System.Collections.Concurrent;
using System.Reflection;
using System.Linq.Expressions;
using System.Threading;
using System.Threading.Tasks;

int split = 0;
using var barrier = new Barrier(2);
void SplitIncrement() { int before = Volatile.Read(ref split); if (!barrier.SignalAndWait(TimeSpan.FromSeconds(5))) throw new TimeoutException(); Volatile.Write(ref split, before + 1); }
OwnedThreads.Run(SplitIncrement, SplitIncrement);
int atomic = 0;
OwnedThreads.Run(Enumerable.Range(0, 4).Select(_ => (Action)(() => { for (int i = 0; i < 100; i++) Interlocked.Increment(ref atomic); })).ToArray());
Console.WriteLine($"separate-read-write:{split}");
Console.WriteLine($"atomic:{atomic}");

public static class OwnedThreads
{
    public static void Run(params Action[] actions)
    {
        var errors = new ConcurrentQueue<Exception>();
        var threads = actions.Select(action => new Thread(() => { try { action(); } catch (Exception error) { errors.Enqueue(error); } }) { IsBackground = true }).ToArray();
        foreach (var thread in threads) thread.Start();
        foreach (var thread in threads) if (!thread.Join(TimeSpan.FromSeconds(8))) throw new TimeoutException("Owned worker did not finish");
        if (!errors.IsEmpty) throw new AggregateException(errors);
    }
}