Browser hacking: Let's add a JIT compiler to LibJS

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[@District8190]

As much as I'm not super happy about you moving away from the old stance of keeping LibJS as an extremely undestandable bytecode VM, these videos have been extremely interesting. I guess I've never looked too far into JIT implementations, and your videos end up making me accidentally discover new details as usual.

[@driedurchin]

Well, if you watched the previous video, he did mention that his intent is to still keep the JIT simple as well, so that the quality you're talking about is still present. Obviously, some complexity will be added but I guess the Serenity team will decide if it's worth it.

[@thaddaeusmarkle1665]

It seems like the bytecode is still gonna be there, its just that now it can be either interpreted or compiled. The interpreter is also still gonna stay around, this is just another option.

[@bbq1423]

It could perhaps be useful to restrict the process running the jitted code into not being able to run any syscalls, it's only there to run the state machine after all.

[@kreuner11]

How would it communicate back with the main thread? There is a tool for restricting the types of syscalls you can make called pledge, here it'll have the minimum pledge likely just for IPC

[@yjk_ch]

It would still need some way to talk back to JS engine, though. But I think at least JIT part cen theoretically become a separate process with very minimal privileges(using pledge()).

[@bbq1423]

@@kreuner11 If the main process and the child process have a shared region of memory which the child has write access to (maybe not even read ¯\_(ツ)_/¯) then I believe that you could do the communication completely without syscalls.

[@perotubinger]

Great new video series! Calling it a “series” because there a hopefully many more to come. ❤

[@DanelonNicolas]

took me a week to make something similar to my own language... Andreas did it in roughly three hours? hahaha awesome, kling!

[@dealloc]

Andreas also worked on WebKit, so fair game :D

[@LeoBerardino]

Super awesome videos @andreas. We are enjoing each minute of the JIT implementation. Thank you for that :)

[@Hector-bj3ls]

Your desktop background is literally me right now. I'm at my desk with my drink and my laptop, wrapped up in my fancy poncho.

[@andrewkaster4033]

void*p and size_t size? Our Span type is crying 😢

[@dbarenholz]

More JIT videos please! These are so fun!

[@solcloud]

This will be interesting, thank you for new series 😍

[@JustATempest]

If it's abstract enough, It could be possible to reuse a lot of this code, when adding support for WebAssembly.

[@tobiasfrey9573]

Love your videos

[@justanormalperson]

These videos are great :^)

[@maixicek]

Awesome jeet series :)

[@andreialdea6072]

the Netflix series on these channel always end up on JS in some way 😅

[@staswisniewski4101]

Well hello friends

[@PlutoniumJesus]

@34:18 What about MOVS?

[@JordanWerthman]

I am a bit confused how Array/LocalArrayBase are not being overwritten since they are stored in caller-saved (R8/R9) registers and you over-write them with the arguments for the native function calls before you save them on the stack? I didn’t see the code on GitHub so maybe I am misremembering or confused but that feels like it would cause issues.

[@getpunned]

Get jitty with it

I need that wallpaper.

[@hxllside]

Is this stuff already pushed anywhere?

[@awesomekling]

Yeah, the branch is in my serenity fork on GitHub: github.com/awesomekling/serenity/tree/libjs_jeet

[@hxllside]

@@awesomekling Thanks!

[@nopair5688]

🤓🙏🙌✌

[@NoOne-ev3jn]

Hey, how can someone become as good as you?

[@awesomekling]

Mainly by doing a lot of programming and trying to do things even if they seem hard :)

[@CYXXYC]

1:05:54 did he say the p word

[@YuTv1408]

Coding is quiet boring and frustrating. Kinda toxic if you think about it

[@SimonBuchanNz]

... Huh?

[@YuTv1408]

Just kidding....lololol. that face 😅😅

[@slendi9623]

WHF