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Comment by sciencejerk | Hacker News Reader

I recently heard that Super Mario 64 (N64) modding community reverse engineered the game enough to recreate more-or-less accurate C code that can be compiled in binaries to execute on many popular target architectures. Have you managed to get beloved games into modifiable C code? Or is it more common to invest a lot of work to document assembly language functions? I know some old assembly but no idea what is involved at a high level. Maybe you explain in your lessons?

Also, how to folks obtain binaries? Presumably unless there is a source code breach or vulnerability, source never gets exposed, is thst correct?

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Mario 64 was byte for byte decompiled to C. It was helped by using the Debug symbols accidentally(?) compiled into the final version of the game.

Otherwise they reference rips of the original game.

> It was helped by using the Debug symbols accidentally(?) compiled into the final version of the game.

Don't think this was the case, what helped was it being compiled without optimizations.

Most games will have been written in a higher level language first (like C or C++) and then compiled into assembly. With matching decomp, we write C, compile it to assembly, and see how much it matches the retail assembly. Using this we can write C that we theorise is almost identical to how it would have been written originally. There are things lost during the compilation process (like comments, function names, etc) these we have to name manually and it's a long process to do! But yes, the goal is to have C at the end and once you have C you can recompile using a different compiler and target any architecture you like

I suspect LLMs would do a good first pass with function naming.

They do an alright job, but they deffo need human-in-the-loop for the best results. I wrote on my blog about how I wrote an MCP to communicate with the Dolphin emulator. Allows Claude Code to set breakpoints, read the memory, write the memory, etc. It was a super fun way to work with Claude and has made naming functions/structs/fields/etc much easier! https://jpb.dev/blog/dolphin-debugger-mcp/

Thanks for replying! Going to check out your educational resources

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