Windows + CUDA

[ax3l]

We need to document and test how to build AMReX on Windows with GPU (CUDA) support. Downstream, we have users for ImpactX/HiPACE++/WarpX actively asking for this feature.

So far, @robertmaynard @sayerhs @mic84 and me gave this a stab in #1585. But we could not yet find a working CI configuration.

[pkufourier]

I suggest you to use WSL under Windows, and build AMReX+CUDA like what exactly is done under Linux system. This is what I am doing right now. The efficiency of WSL is good (like original Linux). The only difference is the cuda installation under WSL is a little difference from the original Linux system, see the guides on nvidia websites. Meanwhile, the unified memory feather can not be used under WSL, therefore you should set "amrex.the_arena_is_managed=0" to ensure the program can run correctly.