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Date: Tue, 10 Dec 2013 10:04:14 +0000
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Subject: Re: [Qemu-devel] save compiled qemu traces.
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Xin Tong <trent.tong@gmail.com>, QEMU Developers <qemu-devel@nongnu.org>


peter.maydell@linaro.org writes:

> On 9 December 2013 06:36, Xin Tong <trent.tong@gmail.com> wrote:
>> Is it possible for QEMU to obviate some of the translations by attaching a
>> signature (e.g. a hash) with every translated basic block and try to reuse
>> translated basic block based on the signature as much as possible ? Reuses
>> can be a result of rerunning programs or same libraries statically linked to
>> programs.
>
> We already cache translated results. See tb_find_fast()
> and tb_find_slow() which do the lookup into the cache.

These are for the current execution context though aren't they? I
thought Xin was talking about caching translations between invocations
of QEMU.

I suspect address space randomisation would be another wrinkle in the
side of any such scheme though.

>
> thanks
> -- PMM

-- 
Alex Bennée
QEMU/KVM Hacker for Linaro