Re: [Qemu-devel] KVM call agenda for tuesday 31

[Avi Kivity <avi@redhat.com>]

On 03/05/2012 05:50 PM, Peter Maydell wrote:
> On 5 March 2012 15:43, Andreas Färber <afaerber@suse.de> wrote:
> > Mid-term also depends on how me want to proceed with LPAE softmmu-wise
> > (bump "arm" to 64-bit target_phys_addr_t, or do LPAE and AArch64 in a
> > new "arm64").
>
> For LPAE I would have thought we want to make "arm" go to a 64 bit
> target_phys_addr_t, since that's exactly what it is: same old
> ARM architecture with wider physical addresses :-)
>
> I notice that for the architectures we currently have that have
> 32 and 64 bit versions we have separate {i386,x86_64}-softmmu,
> {ppc,ppc64}-softmmu, {mips,mips64}-softmmu. What's the advantage
> of separating out the 64 bit flavours that way rather than
> having everything be a single binary?

The registers are smaller; if target_ulong fits in a long then
everything is faster.

Although, you could pretend that target_ulong is 32-bit when in 32-bit
mode, and zero the high half when switching modes, if the target allows
it (I believe i386->x86_64 does, but 8086->i386 does not).

-- 
error compiling committee.c: too many arguments to function