No decompiler can guarantee 100% functional correctness; you will likely need to manually fix logic errors in the recovered code.

If you are decompiling your own lost code and still have the compiler environment, try to generate a symbol map. This provides a "Rosetta Stone" for the decompiler.

Developed by the NSA, Ghidra is excellent at "decompiling" machine code back into a C-like pseudocode. While it won't give you PureBasic syntax, it will reconstruct the logic (loops, conditions, and function calls).

This is not magic; it is rigorous cross-referencing and data flow analysis—the hallmark of a professional tool over a script-kiddie toy.