Re: [Qemu-devel] [PATCH 1/16] ARM Add ARM 920T identifiers

[Laurent Desnogues <laurent.desnogues@gmail.com>]

On Tue, May 26, 2009 at 11:56 AM, Jamie Lokier <jamie@shareable.org> wrote:
> Laurent Desnogues wrote:
>> On Tue, May 26, 2009 at 11:39 AM, Vincent Sanders <vince@kyllikki.org> wrote:
>> > I will post the updated patch to the list shortly. Please be assured
>> > that every program we have tried (boot loaders, Linux, BSD etc.)
>> > appears to function as expected, to the point it had not been
>> > apparient the 920 was a different ISA version to the default emulation.
>> >
>> > So while this is indeed a technical issue, in practice it doesnt seem
>> > to be a major problem.
>>
>> It could be a major problem if you start playing with ARM/Thumb
>> interworking.
>
> I'm curious.  How would code built for ARMv4T interworking fail on an
> ARMv5T emulator?

It shouldn't.  I was thinking about how most people are misusing their
toolchain and think that if QEMU runs correctly some code, it should
run on the target.  In that particular case, that will fail :-)  For instance
LDM with PC used as procedure return does not behave the same
in v4T and v5 IIRC.


Laurent