Re: [Lightning] AMD64 GNU Lightning port & using lightning....

[Paolo Bonzini]

> I'm wondering why GNU lightning is not more used.
The focus seems to be moved to libjit... :-P
> In particular, 
> I am surprised that, given that Paolo is the maintainer of GNU sed 
> -and other GNU utilities- GNU lightning is not used there.
>   
Well it is used by GNU Smalltalk (the only GNU program that I maintain 
together with GNU sed)...
> I do know that most commands are disk bound (including grep & sed) 
> but I still believe they could be speeded up by using Lightning 
> there (to transform the automaton into code).
>   
Well, complex sed scripts are not necessarily disk bound.  However, the 
automaton is implemented in the regex matcher, and I can see quite a few 
problems in that:

1) the glibc regex matcher is incredibly complex (nowhere near a 
"simple" syntax-directed matcher like PCRE's) in order to support, for 
example, internationalization.

2) lightning is not very portable, even though PowerPC/x86 alone cover 
the wide majority of deployed systems -- x86/64 would be a big boost indeed.

3) the glibc maintainer is quite "strict" in what he allows to go in glibc.

Paolo