Re: GNAT's stack checking in Ubuntu 9.04 (and Shootout regex-dna)

[Ludovic Brenta <ludovic@ludovic-brenta.org>]

jonathan wrote on comp.lang.ada:
[Using one's own copy of GNAT.Spitbol.*]
> The first thing I tried worked rather well: I replaced
>
>    Stack_Size : constant Positive := 2000;
>
> with
>
>    Stack_Size : constant Positive := 129;
>
> in GNAT_spitbol.patterns.
>
> The program running time (single-core) dropped from
> 47 seconds to 32 seconds.
[...]
> Last remark: someone with experience using the
> spitbol routines might be able to optimize
> further.  There are tricks using "anchors"
> mentioned in spec of GNAT.spitbol.patterns.

Oh, I think you just struck the right chord here, Jonathan. Georg has
been harping abouf GNAT.Spitbol for a long time now :) Thanks for your
interesting feedback; I have to use strict discipline not to get
involved in those addictive benchmarks myself :)

--
Ludovic Brenta.