How to clone a table in LJ2-friendly way?

[Alexander Gladysh <agladysh@...>]

Hi, list!

Apologies if this question was asked before. If so, please point me in
the right way.

I have a code that clones tables a lot. I want to make that code run faster.

Looks like LuaJIT 2 does not like our implementation of table clone
(or copy) function:

https://github.com/lua-nucleo/lua-nucleo/blob/master/lua-nucleo/table-utils.lua#L282-306

When I run luajit2 -jv -jdump on the code, it complains a lot about
that trace being blacklisted.

So, I have two questions:

1. What is the modern way to profile with LJ2? Is there some
description on how to analyze -jdump output? (I think that maybe I
seen one here in the Lua ML, but I lost the link. Can it be included
into some LJ2 FAQ or something? Sorry for being lazy.)

2. How to write a table clone function with a contract, similar to our
tclone(), that would be more LJ2-friendly?

Thanks,
Alexander.