[FFmpeg-devel] [PATCH] libavcodec/hevcdsp: port SIMD idct functions from 32-bit.

[Martin Storsjö]

Hi Reimar,

On Sat, 16 Jan 2021, Martin Storsjö wrote:

>>>> +.macro idct_16x16 bitdepth
>>>> +function ff_hevc_idct_16x16_\bitdepth\()_neon, export=1
>>>> +//r0 - coeffs
>>>> +        mov             x15, lr
>>>> +
>>> 
>>> Binutils doesn't recognize "lr" as alias for x30
>> 
>> It didn’t have an issue in the Debian unstable VM?
>> That seems like the kind of workaround where it would be
>> better to leave a comment with more info, if you know
>> what exactly is affected.
>
> Binutils 2.28 doesn't recognize "lr" while 2.30 does, it seems.
>
> FWIW, all the existing aarch64 assembly just uses "x30" to refer to this 
> register, none of it uses "lr".

Do you want to follow up on this patch? IIRC changing it to use "x30" 
instead of "lr" was the only blocker from my point of view (and the 
add_residual patch that goes on top of it was mostly fine as well)?

// Martin