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Date: Thu, 30 Jul 2015 09:55:38 +0200
From: Aurelien Jarno <aurelien@aurel32.net>
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Subject: Re: [Qemu-devel] Debian 7.8.0 SPARC64 on qemu - anything i can do
 to speedup the emulation?
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To: Dennis Luehring <dl.soluz@gmx.net>
Cc: qemu-devel@nongnu.org, Karel Gardas <gardask@gmail.com>

On 2015-07-30 05:47, Dennis Luehring wrote:
> so your aarch64 is just less todo for qemu - not EVERY >= 16bit memory
> access needs swapping or needs check for unaligned access to emulate
> bus-erros

On recent Intel CPU, the byteswapping comes for free (MOVBE
instruction).

About the unaligned access it's actually the reverse. The fact that
aarch64 does unaligned access means they have to go through the slow
path (I have posted a patch to improve that). On sparc given that all
access are aligned means there are more chances to go through the fast
path.

-- 
Aurelien Jarno                          GPG: 4096R/1DDD8C9B
aurelien@aurel32.net                 http://www.aurel32.net