From: "Edmund Horner" <ejrh AT paradise DOT net DOT nz>
Newsgroups: comp.os.msdos.djgpp
References: <8smgof$l4f$1 AT nnrp1 DOT deja DOT com>
Subject: Re: Performance 2.7.2 -> 2.8.1
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Date: Fri, 20 Oct 2000 02:25:52 +1300
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To: djgpp AT delorie DOT com
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Reply-To: djgpp AT delorie DOT com

It is unclear whether you mean the compiler is running slowly, or the
compiled program is running slowly.

Firstly, you talk of "code generation", applying to what the compiler does.
Then you mention an optimising option "-mpentium", which applies to programs
compiled.

Where exactly have you noticed performance degradation?  (I do remember
reading that the optimisations enabled by -O, etc. have changed between
versions, but this should only give the compiler more work to do.)

Edmund.

<gdemont AT my-deja DOT com> wrote in message news:8smgof$l4f$1 AT nnrp1 DOT deja DOT com...
> Hi all. Did someone notice a degradation
> of performance of code generation with -O2,
> from GCC 2.7.2 to 2.8.1 in certain contexts,
> on Pentium processors, even though 2.8.1 brought
> the "-mpentium" option ?
>
> Could it be specific to the DOS port or is it a
> bad blending of new optimisation techniques ?
> Could GCC 2.9.5+ revert that apparent tendency ?
>
> TIA for enlightenment!
> Gautier
>
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.