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Date: Mon, 26 Sep 2011 20:08:16 +0100
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From: Peter Maydell <peter.maydell@linaro.org>
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Subject: Re: [Qemu-devel] [PATCH v2] tcg: Remove stack protection from
	helper functions
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To: Blue Swirl <blauwirbel@gmail.com>
Cc: Laurent Desnogues <laurent.desnogues@gmail.com>, Jan Kiszka <jan.kiszka@siemens.com>, Anthony Liguori <aliguori@us.ibm.com>, Mulyadi Santosa <mulyadi.santosa@gmail.com>, qemu-devel <qemu-devel@nongnu.org>

On 26 September 2011 19:20, Blue Swirl <blauwirbel@gmail.com> wrote:
> It would be interesting to have some benchmarks. I'd expect that most
> of the run time is spent within generated code, the next largest item
> should be the translator and any helpers should be marginal.

Depends a lot on the target, I suspect. On ARM at the moment
we spend huge amounts of time (30%+ of runtime) in a handful
of helpers like sub_cc because we haven't optimised the handling
of subtract and test to do things inline. (On my todo list but
performance in general is behind feature work. I have a half a
patchset that I haven't got back to yet.)

Which is kind of echoing your remarks about benchmarks, really.

-- PMM