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From: Laurent Desnogues <laurent.desnogues@gmail.com>
To: qemu-devel@nongnu.org
Subject: Re: [Qemu-devel] Re: branches are expensive
Date: Thu, 19 Mar 2009 11:30:52 +0100	[thread overview]
Message-ID: <761ea48b0903190330j663a388akf65fb78b9579ddb9@mail.gmail.com> (raw)
In-Reply-To: <gpt5ht$utu$1@ger.gmane.org>

On Thu, Mar 19, 2009 at 11:07 AM, Steffen Liebergeld <usenet@gmx.eu> wrote:
>
> I've tested Qemu 0.10.0 and with i386-softmmu on a i386 host I get the
> following numbers:
> direct jump count 70%, 2 jumps 54%
>
> For qemu-system-arm on an ARM host, the numbers look like this:
> direct jump count 47%, 2 jumps 40%
>
> For completeness I tested qemu-system-arm on a i386 host as well:
> direct jump count 44%, 2 jumps 37%
>
> So it looks like the chaining on ARM targets is not as effective as on i386
> targets (regardless of the guest, I used the same guest setup, compiled for
> different architectures, on all tests). Do you have any ideas why this is the
> case?

Different instruction sets, different compilers.  You'd better compare
guest code before drawing any conclusion.


Laurent

  reply	other threads:[~2009-03-19 10:30 UTC|newest]

Thread overview: 14+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-03-17 11:05 [Qemu-devel] branches are expensive Steffen Liebergeld
2009-03-17 11:18 ` Avi Kivity
2009-03-17 11:32   ` [Qemu-devel] " Jan Kiszka
2009-03-17 12:31     ` Steffen Liebergeld
2009-03-17 12:51       ` Paul Brook
2009-03-17 13:24         ` Avi Kivity
2009-03-19 10:07         ` Steffen Liebergeld
2009-03-19 10:30           ` Laurent Desnogues [this message]
2009-03-19 10:39             ` Steffen Liebergeld
2009-03-19 11:06               ` Laurent Desnogues
2009-03-19 10:52           ` Avi Kivity
2009-03-19 11:34           ` Paul Brook
2009-03-17 11:36   ` Steffen Liebergeld
2009-03-17 13:30 ` [Qemu-devel] " Laurent Desnogues

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