Re: [Qemu-devel] [PATCH 0/2] Disassembly with external objdump

[Claudio Fontana <claudio.fontana@huawei.com>]

Hi, resuming this conversation about external objdump,

On 10.08.2013 21:47, Richard Henderson wrote:
> On 08/10/2013 06:53 AM, Max Filippov wrote:
>> On Sat, Aug 10, 2013 at 8:42 PM, Richard Henderson <rth@twiddle.net> wrote:
>>> On 08/10/2013 05:45 AM, Peter Maydell wrote:
>>>> Well, it depends. If we're going to dump all the in-tree
>>>> disassemblers and always use an external objdump, that's fine.
>>>
>>> It's tempting, given that the only internal disassemblers that
>>> are not missing opcodes are for the extinct cpus.
>>
>> Will that leave those CPUs without x/i support from monitor?
> 
> Yes.
> 
> One could always have qemu fork to objdump too.  Though finding the
> right one could be tricky without help.

I lost track of what you mean here.. that we could implement x/i support also using an external objdump?

I got my first actual run of a qemu with integrated libvixl from ARM for disassembly output of aarch64 code, and the results are substandard.
Many instructions are missing, in particular all PC relative instructions, and the README warns about multiple other problems.
It also introduces dependencies from scons, C++, and can only build and run on 64bit LP64 hosts.
Using external objdump would be very much better for aarch64.

What about making the external objdump the first class citizen here, and removing all the old  stuff? Or just keeping it as fallback?

> 
>> Does anybody use it?
> 
> That I can't answer.

As I started the aarch64 tcg task I just used gdb's disassembly feature for achieving that goal.
However, since the feature is already there and people rely on it, maybe it could be done with external objdump as well?

> 
> 
> r~

Ciao,

Claudio