How to use x64 Interlocked Operations against MemoryMappedFiles in .net

Question

I need to use Interlocked Operations (CompareExchange, Increment etc.) against memory in MemoryMappedFiles in .NET.

I found this answer to a very similar question. The problem is that Interlocked Operations are not exported from kernel32 (or any other) dll on 64 bit OS (see e.g. http://blog.kalmbachnet.de/?postid=46).

Is there any other way how I can call Interlocked functions on a block of memory in a 64bit .NET process?

Answer 1

Write yourself a small C++/CLI helper library that provides interlocked operations consumable by managed code.

I believe the fastest interop path would be to expose a managed class that internally calls into an unmanaged function which itself makes use on the interlocked intrinsics. That way you don't even have to go through PInvoke.