Re: [Qemu-devel] [PATCH v1 2/4] target-arm: A64: Handle blr lr

[Peter Maydell]

On 1 May 2014 10:02, Alex Bennée <address@hidden> wrote:
>
> Edgar E. Iglesias <address@hidden> writes:
>
>> From: "Edgar E. Iglesias" <address@hidden>
>>
>> For linked branches, updates to the link register happen
>> conceptually after the read of the branch target register.
>>
>> Signed-off-by: Edgar E. Iglesias <address@hidden>
>
> I'm trying to think of a case where this could actually cause a problem
> but I can't. However from a clarity/correctness point of view it's
> better.

Well, we actually misexecute "BLR LR" otherwise, right?
That's probably not very common but there's no reason it
might not occur (eg call to a function pointer from a
function where LR has been saved on entry and is free
for use as a generic tempreg).

Cc: address@hidden

thanks
-- PMM