如何运行 luajittex？

Question

lua[hb]tex我很好奇想比较一下vs的性能luajit[hb]tex。我不知道如何运行后者。简单地运行luajithbtex不适用于 LaTeX 文件，因为它只是一个普通的 TeX 引擎。以下是我尝试过的：

• 复制fmtutil.cnf自/usr/local/texlive/2021/texmf-dist/web2c至~/.texlive2021/texmf-var/web2c
• 更改lualatex luahbtex language.dat,language.dat.lua lualatex.ini为。lualatex luajithbtex language.dat,language.dat.lua lualatex.ini​~/.texlive2021/texmf-var/web2c/fmtutil.cnf
• 然fmtutil-user --all。

最后一个命令运行时失败luajithbtex -ini -jobname=lualatex -progname=lualatex lualatex.ini </dev/null：

This is LuajitHBTeX, Version 1.13.0 (TeX Live 2021)  (INITEX)
 restricted system commands enabled.
(/usr/local/texlive/2021/texmf-dist/tex/generic/tex-ini-files/lualatex.ini
(/usr/local/texlive/2021/texmf-dist/tex/generic/tex-ini-files/luatexconfig.tex
(/usr/local/texlive/2021/texmf-config/tex/generic/tex-ini-files/pdftexconfig.te
x)) (/usr/local/texlive/2021/texmf-dist/tex/latex/base/latex.ltx
(/usr/local/texlive/2021/texmf-dist/tex/latex/base/texsys.cfg)
./texsys.aux found


\@currdir set to: ./.


Assuming \openin and \input
have the same search path.


Defining UNIX/DOS style filename parser.

catcodes, registers, parameters,
LaTeX2e <2020-10-01> patch level 4
(/usr/local/texlive/2021/texmf-dist/tex/latex/l3kernel/expl3.ltx
(/usr/local/texlive/2021/texmf-dist/tex/latex/l3kernel/expl3-code.texerror load
ing module expl3 from file /usr/local/texlive/2021/texmf-dist/tex/latex/l3kerne
l/expl3.lua:
    ...cal/texlive/2021/texmf-dist/tex/latex/l3kernel/expl3.lua:179: unexpected sy
mbol near '/'
stack traceback:
    [C]: at 0x00451b20
    [C]: in function 'require'
    [\directlua]:1: in main chunk.
l.165     \directlua{require("expl3")}
                                    %
?
! Emergency stop.
l.165     \directlua{require("expl3")}
                                    %
!  ==> Fatal error occurred, no output PDF file produced!
Transcript written on lualatex.log.

我究竟做错了什么？