From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham
	autolearn_force=no version=3.4.4
X-Google-Thread: a07f3367d7,3a6a9f1d654285ba
X-Google-Attributes: gida07f3367d7,public,usenet
X-Google-NewGroupId: yes
X-Google-Language: ENGLISH,ASCII
Path: 
 g2news2.google.com!news2.google.com!postnews.google.com!h21g2000yqa.googlegroups.com!not-for-mail
From: Martin <martin.dowie@btopenworld.com>
Newsgroups: comp.lang.ada
Subject: Re: Ada Shootout program for K-Nucleotide (patches)
Date: Tue, 4 Aug 2009 01:23:14 -0700 (PDT)
Organization: http://groups.google.com
Message-ID: 
 <17c58792-2251-4762-9ecb-6f839851ed95@h21g2000yqa.googlegroups.com>
References: <4a743343$0$32674$9b4e6d93@newsspool2.arcor-online.net>
NNTP-Posting-Host: 20.133.0.8
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
X-Trace: posting.google.com 1249374194 9115 127.0.0.1 (4 Aug 2009 08:23:14
 GMT)
X-Complaints-To: groups-abuse@google.com
NNTP-Posting-Date: Tue, 4 Aug 2009 08:23:14 +0000 (UTC)
Complaints-To: groups-abuse@google.com
Injection-Info: h21g2000yqa.googlegroups.com; posting-host=20.133.0.8;
	posting-account=g4n69woAAACHKbpceNrvOhHWViIbdQ9G
User-Agent: G2/1.0
X-HTTP-UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-GB; rv:1.9.1.2)
	Gecko/20090729 Firefox/3.5.2,gzip(gfe),gzip(gfe)
Xref: g2news2.google.com comp.lang.ada:7559
Date: 2009-08-04T01:23:14-07:00
List-Id: <comp.lang.ada>

On Aug 1, 1:21=A0pm, Georg Bauhaus <rm.tsoh.plus-
bug.bauh...@maps.futureapps.de> wrote:
> This is about the K-Nucleotide program at the
> Computer Language Benchmark Game,http://shootout.alioth.debian.org/u32/be=
nchmark.php?test=3Dknucleotide&...
> where some Ada programs have started to fail.
>
> In order to have one of them work again, I have patched
> knucleotide.gnat, with some success. =A0New version is here:http://home.a=
rcor.de/bauhaus/Ada/knucleotide.gnat
>
> Comments? =A0Does it work on your machine?
>
> The two changes:
>
> 1 - [stack exhaustion] a loop reading input lines into an
> =A0ubounded =A0string replaces the recursive String "&"ing
> =A0procedure. (Noting that the input text file is ~240MB ...)
>
> 2 - [heavy bounded strings] a lightweight bounded string ADT
> =A0replaces an instance of Generic_Bounded_Length, yielding
> =A0an improved running time of ~22s down from ~30s for
> =A0the 2,500,000 case.
>
> Still, on a relatively small virtual machine running 64bit
> Debian, the program cannot handle the 25,000,000 case.

Is the line...:

      return Left.Last =3D Right.Last
	and then Left.Data(1 .. Left.Last) =3D Right.Data(1 .. Right.Last);

...doing the 1st check twice? Once explicitly and then won't it be
checked again in 'Standard."=3D" (L, R : String) return Boolean'?

It might be faster to do the check if it is more likely to be False
than True (could be cheaper than a call to Standard."=3D") but it might
be worth testing out...

Cheers
-- Martin