Is this actually surprising? Once you use stuff like vectorization you want to get as much performance out of a system. If you're not natively compiling for a system, you won't get any performance.

Using AVX2 and using an emulator have contradictory goals. Of course there can be a better emulator or actually matching hardware design (since both Apple and Microsoft actually exploit the similar register structure between ARM64 and x86_64). However, this means you have increased complexity and reduced reliability / predictability.

Author here - have to say, thanks for reading all the way to the end, you don't always see people do that ;)

I put a spoiler at the top too, to avoid trying to make people read the whole thing. The real bit is that chart, which I think is quite an amazing result.

You're right re building. We're a compiler vendor, so we have a natural interest in what people should be targeting. But even for us the results here were not what we expected ahead of time.

Is Chrome for Windows compiled in ARM too or does it use the Windows under emulation?

The reason I ask is that I believe Windows Chrome is (like many Windows binaries) compiled with lots of the advanced CPU features disabled (e.g. AVX512) because they're not available on older PCs. Is that true?