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Mail Archives: pgcc/2000/01/29/10:09:48

Date: Sat, 29 Jan 2000 14:35:44 +0100
From: Marc Lehmann <marc AT gimp DOT org>
To: pgcc AT delorie DOT com
Subject: Re: pgcc and egcs alignment -- function, basic block and string
Message-ID: <20000129143544.G1024@cerebro.laendle>
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On Fri, Jan 28, 2000 at 08:56:48PM -0800, Chris Sears <cbsears AT ix DOT netcom DOT com> wrote:
> Is there a switch to turn this alignment off so that I could test it?

Yes, -malign-loops=xxx, -malign-functions=xxx etc.. Just read the
manual(tm).

> Admittedly, a cache line is word aligned as well,
> but wouldn't .align 4 suffice to align to a word boundary?

It depends. The only way data alginment hurts is by wasting space, which
is rarely a problem (despite cache problems). aligning to a cache line
helps in practise, although one would think that natural alignment would
suffice.

Maybe a aligning on longwords is a good trade-off, but that needs
extensive benchmark data.

> > I will verify this tommorow and in case you are correct, I will fix this bug.
> If possible could you send me email telling me what happened.

this list, please ;->

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      ---==---(_)__  __ ____  __       Marc Lehmann      +--
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