There's an interesting vein of research work here in making software reverse engineering more difficult, and measuring how much more difficult. A precursor to

There's an interesting vein of research work here in making software reverse engineering more difficult, and measuring how much more difficult. A precursor to decompilation is control flow analysis, the production of the control flow graph you see in the "before" stages in all of the examples in this post. You can go one step further, on a good day, and make it very difficult (perhaps very very difficult, perhaps impossible) to recover a precise control flow graph for a function. There are a few different ways to do this, and I like these approaches more than targeting specific heuristics in IDA/Hexrays because, on a good day for the obfuscator, you can make a theoretical statement about the work effort required to un-do the obfuscation. If you can make that work effort large, then you start to have a security guarantee that is a shade of the security guarantee you get in cryptography. The methods outlined in the parent blog post are great because you can start using them today, but if they annoy Ilfak enough, he'll fix them and they'll stop working.