I know /nothing/ about emulator development, but I wonder what the performance of a Switch emulator written for the M1 using Metal for graphics would look like. I'd expect the Switch and the M1 both being ARM would be an advantage? Would be curious to learn more if anyone in this space wants to weigh in.
As for the CPU architecture, probably the dynamic recompilation step that turns ARM code to x86 could be skipped.
Just to show, how viable it is, there's a closed source emulator for Android that's probably base on Yuzu (with surprising good performance):
https://www.youtube.com/watch?v=Ex_AArUJ8cY
The suspicion coming from it having the same bugs as yuzu itself.
I don't know if Switch could be emulated with Wine-like approach, if not, it would be tricky to intercept syscalls without an ARM-to-ARM DBT. Performance impact should be minimal though.
Both seem to be possible, since arm64 uses fixed instruction length. I don't think svc calls can be trapped in-process with user privileges, and it's even less likely it can be done in a portable way.
So probably some level of source-patching needs to take place, but it requires just a high-level understanding of the code, not a full decompilation-recompilation.
You don't need a DBT, VMs on arm64 are very cheap. You can just use Hypervisor.framework really.
Modern emulators are a lot like Wine these days where they are just translating the custom api calls to something that works on a desktop OS.
It actually depends more on the memory ordering. To speed up the running of x86 apps, the M1 has a strong memory-ordering mode designed to match x86.
I've been running the PCSX2 PS2 emulator on M1 (rendering using either OpenGL backend or Software), it runs my favorite game SSX Tricky great, including joystick support, sound and smooth graphics.
https://wololo.net/2021/09/08/release-spine-ps4-emulator-v-2...
FWIW, M1 Macs are also one of the few ARM platforms that will let you[0] actually install regular GNU-and-Wayland desktop Linux. I think the current crop of Windows on ARM machines will also let you install Linux, of course. But most Android hardware ranges from mildly to very hostile to users who want regular Linux - even if there's a bootloader unlock, the hardware is going to require all sorts of extra vendor-proprietary drivers that won't work with a standard distro. This also ties in with what I said before about backwards-compatibility across multiple SoCs.
The reason why people treat the M1 as separate from all other ARM hardware is because it actually acts like a computer; providing the performance and control you expect from something bearing the name. Most other ARM vendors are not aiming to provide that.
[0] You do have to sign the kernel with your Owner key, but that's manufacturer-supported, so it counts.
According to Google, Orbital is the one using QEMU.
Also random thought, but can the opposite be achieved? That is, installing Orbis (PS4 OS, based on FreeBSD) on generic PC hardware?
Most emulators interpret the machine instructions in software so there wouldn't be any advantages there. Some are now incorporating dynamic recompilation but I doubt it would have any noticeable impact on ARM vs x86.