- I've just added some new lessons before the first lesson to explain assembly syntax!

- I believe there are around 200-odd instructions, and a lot of them I'm not sure you'll ever see, but I can certainly look at adding something like this

One of the reasons I went down the path of learning decomp myself was because AI had hit a wall. Matching decomp is quite a bit harder than just normal decomp as even simple things like using an if/else instead of a terney actually change the assembly. AI did an amazing job of getting to 95% matches on nearly all functions, but once it got to that tail end, it started to struggle quite a lot and would often just claim "it's impossible". So that's when I pivoted and started learning actual decomp myself so that I could prompt AI better and finish off the star fox adventures decomp!

As for cheating, the community calls this a fake match. I don't check that the code you submit conforms to what I expect, I only check if the assembly matches. You can do interesting things where you do a series of bit shifts and bit masks, and you can replicate an equality operator `a == b` or a low clamp `x < 0 ? 0 : x`. I'm not sure if I'll lock this down or not, for people who have accounts, I can see their submissions so I think I'll play it by ear and see what happens. If it looks like people are constantly fake matching, I can look at tweaking the lessons or locking it down more

Learning how to decompile was challenging. It's difficult to find any good learning resources for it and any open-source projects for this are inactive and/or contain little actual learning material.

So I put together Decomp Academy! Decomp Academy is an interactive way to learn how to decompile PowerPC assembly back into C. The site runs a live Metrowerks CodeWarrior GC/2.0 compiler, converts your C into assembly, and then checks how close your assembly matches the target. If even 1 instruction or bit is off, that's a fail. This is the gold standard for video game decompilation and this is much stricter than a normal decompile.

As of writing there are 250+ lessons on the site and the lessons start at the very basics so anyone with a little programming experience should be able to jump straight in, even if you're not a C expert. Some lessons also have real functions taken from live open source decomp projects (Star Fox Adventures, Mario Party 4, Pikmin, Metroid Prime). The idea being you learn everything you need to know to be able to jump in and contribute to a real decompilation project when done.

The site is completely free, open source and you have access to all lessons without having to sign up. All lessons are stored in markdown in the repo (src/curriculum), it's trivial to add or modify lessons. The site is very new and the lessons are rapidly changing every day with a whole C++ section on the way. The site has already been well received by the decomp community and I'm happy to share it with HN. I'm very keen on others to contribute to this project and I hope this becomes the best resource on the internet for learning the art of decompilation. Please let me know what you think!

Source: https://github.com/JackPriceBurns/decomp-academy-fe

Comments URL: https://news.ycombinator.com/item?id=48703412

Points: 195

# Comments: 78