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Subject: Re: [Qemu-devel] [PATCH 3/3] tcg: Add MO_ALIGN, MO_UNALN
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To: Peter Maydell <peter.maydell@linaro.org>
Cc: Yongbok Kim <yongbok.kim@imgtec.com>, Leon Alrae <leon.alrae@imgtec.com>, QEMU Developers <qemu-devel@nongnu.org>

On 05/13/2015 02:15 PM, Peter Maydell wrote:
> On 13 May 2015 at 22:08, Richard Henderson <rth@twiddle.net> wrote:
>>> Are unaligned accesses always slow-path, by the way?
> 
> Would it be in theory possible to fast-path MO_UNALN
> unaligned accesses if the host CPU supported unaligned
> accesses for whatever load/store insn we use in the TLB
> hit case?

We would also need to test for page boundary crossing.  That would take at
least 3 more insns, for a host that natively supports unaligned accesses.
Whether that's worth it or not would need testing...


r~