Re: [Qemu-discuss] Is x86_64 emulation on ARM much slower than x86 emulation?

[Peter Maydell]

On 23 February 2018 at 07:56, Johannes Riecken
<address@hidden> wrote:
> I don't know if this is the appropriate place to ask, but I noticed that
> upcoming Windows 10 ARM PCs running on Snapdragon 835 only support 32-bit
> emulation for x86. Could that be because the performance of x86_64 machine
> code dynamically binary translated to ARMv8 is too poor?

That looks like a 64-bit Arm CPU, so QEMU will happily run
both 32-bit and 64-bit x86 guest code on it in both system emulation
and linux-user emulation modes.

If you're asking specifically about limitations in whatever Microsoft's
x86 emulation is, you'd need to ask Microsoft about that, since
it's not a QEMU thing.

thanks
-- PMM