There was computer vision stuff in the missile's head (for target tracking), which is where the code was used.

That is a good reason to need a non trivial amount of memory, but I don't think it means there needs to be dynamically allocated memory. That basically implies that there is something unknown ahead of time, but specs, limitations, resolution fps, etc. should all be static.

I think it was a slab allocator made in house. It was a long time ago.