Re: [Qemu-devel] [PATCH] configure: Unify arm and aarch64 disas configury

[Peter Crosthwaite <peter.crosthwaite@xilinx.com>]

On Tue, May 26, 2015 at 1:24 AM, Peter Maydell <peter.maydell@linaro.org> wrote:
> On 26 May 2015 at 09:01, Peter Crosthwaite <peter.crosthwaite@xilinx.com> wrote:
>> On Tue, May 26, 2015 at 12:18 AM, Peter Maydell
>> <peter.maydell@linaro.org> wrote:
>>> On 26 May 2015 at 06:49, Peter Crosthwaite <crosthwaitepeter@gmail.com> wrote:
>>>> From: Peter Crosthwaite <crosthwaitepeter@gmail.com>
>>>>
>>>> The "arm" variant for this case already contains everything needed
>>>> for aarch64. As aarch64 already uses arm as a base architecture, it
>>>> will already have the CONFIG_ARM_DIS defined meaning no functional
>>>> change. So just make the configure code simpler.
>>>
>>> I'm wondering why we needed to put the A64 disassembler into
>>> the "arm" variant at all...
>>>
>>
>> That probably works too. I'm trying to get rid of the dup. respin it?
>
> I think it would look more like the other entries in the case statement,
> so worth trying. Maybe we'll find out why it's done this way :-)
>

OK I am at the bottom of it. The case statement only handles the base
arch and the host arch not the actual target arch. This means the
"arm)" case is all that is called for aarch64 target. the "aarch64)"
case in existing code is presumably to handle an AArch64 host. So the
current code will produce the minimal working configury. My patch will
still work, but will unneedingly add AArch32 disas to AA64 host. A
solution would be to patch that loop to go through all of the base
arch, target arch and host arch. Anyone know of a reason not to do so?

Regards,
Peter

> -- PMM
>