I wouldn’t mind a system where an LLM made instructions for a second system, which was a reliable code rearranging tool.
I am actually working on a GUI for just that [0]. The first problem is solved by having explicit links above functions and classes whether to include them in the context window (with an option to remove bodies of functions, just keeping the declarations). The second one is solved by a special review mode where it auto-collapses functions/classes that were unchanged, and having an outline window that shows how many blocks were changed in each function/class/etc.
The tool is still very early in development with tons of more functionality coming (like proper deep understanding of C/C++ code structure), but the code slicing and outline-based reviewing already works just fine. Also, works with DeepSeek, or any other model that can, well, complete conversations.