https://arstechnica.com/information-technology/2022/12/apple-slices-its-ai-image-synthesis-times-in-half-with-new-stable-diffusion-fix/

On Wednesday, Apple released optimizations that allow the Stable Diffusion AI image generator to run on Apple Silicon using Core ML, Apple's proprietary framework for machine learning models. The optimizations will allow app developers to use Apple Neural Engine hardware to run Stable Diffusion about twice as fast as previous Mac-based methods.