103
Why can't code be uncompiled?
(lemmy.world)
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
this post was submitted on 03 Jan 2024
103 points (95.6% liked)
No Stupid Questions
34938 readers
1475 users here now
No such thing. Ask away!
!nostupidquestions is a community dedicated to being helpful and answering each others' questions on various topics.
The rules for posting and commenting, besides the rules defined here for lemmy.world, are as follows:
Rules (interactive)
Rule 1- All posts must be legitimate questions. All post titles must include a question.
All posts must be legitimate questions, and all post titles must include a question. Questions that are joke or trolling questions, memes, song lyrics as title, etc. are not allowed here. See Rule 6 for all exceptions.
Rule 2- Your question subject cannot be illegal or NSFW material.
Your question subject cannot be illegal or NSFW material. You will be warned first, banned second.
Rule 3- Do not seek mental, medical and professional help here.
Do not seek mental, medical and professional help here. Breaking this rule will not get you or your post removed, but it will put you at risk, and possibly in danger.
Rule 4- No self promotion or upvote-farming of any kind.
That's it.
Rule 5- No baiting or sealioning or promoting an agenda.
Questions which, instead of being of an innocuous nature, are specifically intended (based on reports and in the opinion of our crack moderation team) to bait users into ideological wars on charged political topics will be removed and the authors warned - or banned - depending on severity.
Rule 6- Regarding META posts and joke questions.
Provided it is about the community itself, you may post non-question posts using the [META] tag on your post title.
On fridays, you are allowed to post meme and troll questions, on the condition that it's in text format only, and conforms with our other rules. These posts MUST include the [NSQ Friday] tag in their title.
If you post a serious question on friday and are looking only for legitimate answers, then please include the [Serious] tag on your post. Irrelevant replies will then be removed by moderators.
Rule 7- You can't intentionally annoy, mock, or harass other members.
If you intentionally annoy, mock, harass, or discriminate against any individual member, you will be removed.
Likewise, if you are a member, sympathiser or a resemblant of a movement that is known to largely hate, mock, discriminate against, and/or want to take lives of a group of people, and you were provably vocal about your hate, then you will be banned on sight.
Rule 8- All comments should try to stay relevant to their parent content.
Rule 9- Reposts from other platforms are not allowed.
Let everyone have their own content.
Rule 10- Majority of bots aren't allowed to participate here.
Credits
Our breathtaking icon was bestowed upon us by @Cevilia!
The greatest banner of all time: by @TheOneWithTheHair!
founded 1 year ago
MODERATORS
Thank you, sorry to push further but my understanding is that computers deal with binary so every language is compiled to machine code, which I took as binary.
So if the language has elements being removed and the machine doesn't need them shouldn't you get back out exactly what is needed to do the task? Like if you compiled some code and then uncompiled it you would get the most efficient version of it because the computer took what it needed, discarded the rest and gave it back to you?
It depends on the specifics of how the language is compiled. I'll use C# as an example since that's what I'm currently working with, but the process is different between all of them.
C#, when compiled, actually gets compressed down to what is known as an intermediate language (MSIL for C# specifically). This intermediate file is basically a set of genericized instructions that are not linked to any specific CPU. This is useful because different CPUs require different instructions.
Then, when the program is run, a second compiler known as the JIT (just-in-time) compiler takes the intermediate commands and translates them into something directly relevant to the CPU being used.
When we decompile a C# dll, we're really converting from the intermediate language (generic CPU-agnostic instructions) and translating it back into source code.
To your second point, you are correct that the decompiled version will be more efficient from a processing perspective, but that efficiency comes at the direct cost of being able to easily understand what is happening at a human level. :)
Could I trouble you to go deeper? I'm think I'm getting it but if we were to say uncompile GTA V or Super Mario Bros, could we make changes and figure it out from there or would it be complete nonsense with no way points to jump in at and get a grip on what is being done.
On a side note I was told once that everything is 1s and 0s and as a result that someone could type a picture of you if they got the order right. This could be why I'm so wrong in my understanding given I'm now assuming this was bullshit.
Here is a real world example of someone doing some reverse engineering of compiled code. Might help you understand what is possible, and some of the processes. https://nee.lv/2021/02/28/How-I-cut-GTA-Online-loading-times-by-70/