Technology

SIMD is pretty simple really, but it's been 30 years since it's been a standard-ish feature in CPUs, and modern compilers are "just about able to sometimes" use SIMD if you've got a very simple loop with fixed endpoints that might use it. It's one thing that you might fall back to writing assembly to use - the FFmpeg developers had an article not too long ago about getting a 10% speed improvement by writing all the SIMD by hand.

Using an NPU means recognising algorithms that can be broken down into parallelizable, networkable steps with information passing between cells. Basically, you're playing a game of TIS-100 with your code. It's fragile and difficult, and there's no chance that your compiler will do that automatically.

Best thing to hope for is that some standard libraries can implement it, and then we can all benefit. It's an okay tool for 'jobs that can be broken down into separate cells that interact', so some kinds of image processing, maybe things like liquid flow simulations. There's a very small overlap between 'things that are just algorithms that the main CPU would do better' and 'things that can be broken down into many many simple steps that a GPU would do better' where an NPU really makes sense, tho.