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Subject: Re: [Qemu-devel] Raspbian in QEMU
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To: Stefan Weil <sw@weilnetz.de>, Peter Hanzel <hanzelpeter@gmail.com>, Peter Maydell <peter.maydell@linaro.org>
Cc: QEMU Developers <qemu-devel@nongnu.org>

On 03/12/2014 11:56 AM, Stefan Weil wrote:
> Am 12.03.2014 19:05, schrieb Peter Hanzel:
>> Thanks.
>>
>> Now it makes sense. Also google now works and led me to
>> https://github.com/bavison/arm-mem.
>> And there is SETEND used.
>>
> 
> It might be possible to handle that special case in QEMU without
> implementing setend:
> 
> That instruction is only used in the implementation of function memcmp.
> When TCG detects a setend instruction, it could check whether the
> surrounding code has the signature of that memcmp implementation and add
> code which calls a memcmp helper function. The setend instruction and
> all the following code of memcmp would be handled as if it were a single
> special multi byte machine instruction.

Ew.  No.  It would be easier to just implement setend, even if badly.

> PS. Link to previous discussion on setend:
> https://lists.gnu.org/archive/html/qemu-trivial/2013-08/msg00086.html
> I cc Richard because he was / is involved, too.

For my part, the endian-aware load/store opcodes I alluded to last
August are now in.


r~