Re: A few gnu M4 extensions

[gwenael chailleu]

Hello Eric,

Well, we were very happy to discover and use gnu M4 and we will be happy if our extension come to be accepted.

Technically speaking, the main drawback is that our version needs to be linked to Judy Arrays library.

there is an advantage associated to this drawback : each improvement of JudyL will have impact on m4. (gprof says that our token recognition JudyL based function takes 16% of the execution time)

 

We will let you evaluate what can be taken (for example there is no prerequisite for the integration of the new builtins) and what must be left aside.

What's next move ? 

Do you want a tgz of our directory ?

Regards,

Gwen

2012/10/19 Eric Blake <address@hidden>

On 10/19/2012 04:00 AM, gwenael chailleu wrote:
> Hello,
>
> Two years ago, with a friend, we decided to develop a new C extension (one
> more!  You can have a look at :
> http://melvenn.com/cawen/the-google-benchmark/ )...
>
> We chose gnu M4 to be the basis of our C99 code generation process.
> To simplify our m4 source files we decided to add a few builtins to gm4.
> The associated test files of these builtins are here attached.

Thanks for taking the time to write an extension.  However, to be
accepted, you would need to assign copyright to your work to the FSF.
Is this something you are interested in pursuing?

>
> We also wanted to add lexicographical order to the user macros and we
> replaced the central recognition hash-map with some kind of ordered map
> based on JudyL Arrays.
>
> results :
>
> 1) no performance loss (very much a minimum!)
>
> 2) we can now add (but we had not yet)  builtins of this kind : for each
> macro beginning with "myPrefix"...
>
> 3) expected performance gain : Doug Baskins is currently reengineering his
> Judy Arrays (http://judy.sourceforge.net/).
> He told us he has already achieved a x2 x4 speed gain on JudyL arrays.
>
> 4) maybe a way to implement a simpler changeword mode ? (keys can be
> non-ascii, can contain embedded 0 and so on)
>
> If you are interested in our work, we would be very happy to talk further
> about it.
>
> Besides, we would like to say "thanks a lot!" to the whole team of gnu M4
> maintainers !
>
> Gwenael & Thomas
>

--
Eric Blake   address@hidden    +1-919-301-3266
Libvirt virtualization library http://libvirt.org