It is not my code, it was originally written by @korli, but he abandoned patch. I propose userland-based (Korli approach is kernel-based) compatibly layer UserlandVM that in theory can run applications for any CPU architecture, not only supported by hardware natively. UserlandVM currently supports running riscv64 applications on x86_64 with software CPU emulator.
x86 → x86_64 need more work because of syscall argument and structures translation and controlling 32 bit CPU mode.