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From: Koen Kooi <k.kooi@student.utwente.nl>
To: openembedded-devel@lists.openembedded.org
Subject: Re: [PATCH/RFC] qt4-embedded: tune QT_ARCH for armv6
Date: Thu, 04 Nov 2010 22:05:37 +0100	[thread overview]
Message-ID: <iav771$87s$1@dough.gmane.org> (raw)
In-Reply-To: <4CD2FAF0.4080905@freyther.de>

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On 04-11-10 19:26, Holger Freyther wrote:
> On 11/04/2010 10:52 AM, Eric Bénard wrote:
>> this is a RFC, I think it can also be used on qt 4.6.x and on armv7.
>> Setting QT_ARCH to armv6 enable some asm optimized functions in QT.
> 
> Do you know the consequences of this change? E.g. in the painting
> engine unaligned memory access will be allowed. I am not sure that Nokia has
> ever benchmarked what is faster (aligned/unaligned) access. So it would be
> very interesting to know the perf difference. E.g. use qttracereply to measure it.
> 
> Phil do you happen to know why unaligned access got allowed starting from
> armv6? How fast will it be?

- From previous experiments the "hardware" unaligned was the same speed as
the sw fixup on armv6.

regards,

Koen
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  parent reply	other threads:[~2010-11-04 21:06 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-11-04  9:52 [PATCH/RFC] qt4-embedded: tune QT_ARCH for armv6 Eric Bénard
2010-11-04 18:05 ` Khem Raj
2010-11-04 18:26 ` Holger Freyther
2010-11-04 19:14   ` Eric Bénard
2010-11-05  9:32     ` Holger Freyther
2010-11-05  9:42       ` Eric Bénard
2010-11-05 10:21         ` Holger Freyther
2010-11-05 10:41           ` Eric Bénard
2010-11-07 19:42           ` Eric Bénard
2010-11-04 20:27   ` Khem Raj
2010-11-04 21:05   ` Koen Kooi [this message]
2010-11-05 11:21   ` Phil Blundell

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