My first implementation of gemma.cpp was kind of like this.
There's such a massive performance differential vs. SIMD though that I learned to appreciate SIMD (via highway) as one sweet spot of low-dependency portability that sits between C loops and the messy world of GPUs + their fat tree of dependencies.
If anyone want to learn the basics - whip out your favorite LLM pair programmer and ask it to help you study the kernels in the ops/ library of gemma.cpp: