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> LuaJIT supports Lua 5.1

From what I understand, LuaJIT was removed before Lua 5.2 was released, so that wasn't the reason.

https://luajit.org/extensions.html

LuaJIT supports most of the features of Lua versions after 5.1 with the major missing feature being 64-bit integers, but like modern JS JITs, it actually uses 31/32-bit ints internally most of the time. Even in Lua 5.4 code, you are using implicit rather than explicit ints 99% of the time.

I haven't run the code to see, but I'm willing to bet that you can copy all the current benchmark code into LuaJIT and it'll run just fine.

> You have no idea.

I know with certainty that deoptimizations were applied to at least some scripts. Here's three examples for Common Lisp, StandardML, and Haskell over some time.

https://zerf.gitlab.io/ComputerLanguageBenchmarksGame2018Arc...

https://github.com/lemire/ComputerLanguageBenchmark/blob/fbe...

https://hackage.haskell.org/package/ajhc-0.8.0.4/src/example...

Here's a C example from Mike Pall (presumably the same guy who created LuaJIT) that also got the deopt treatment by Isaac Gouy.

https://github.com/lemire/ComputerLanguageBenchmark/blob/fbe...

It's not a question of if this happens -- only if it affects Lua (I've never checked).



Wait, that's news to me. Last time I checked, maybe 2 years ago, luajit supported some Lua >5.2 features. But, just a handful of those. Is it truly supporting most of the newer features nowadays?


> extensions.html

On that page, what words do you think support your claim "was removed before Lua 5.2 was released".

> I know with certainty

I made those code changes. I wrote de-optimized as a joke.




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