[FFmpeg-devel] [PATCH v2 02/15] avfilter/vf_bwdif: Add common macros and consts for aarch64 neon

[Martin Storsjö]

On Sun, 2 Jul 2023, John Cox wrote:

> Add macros for dual scalar half->single multiply and accumulate
> Add macro for shift, saturate and shorten single to byte
> Add filter constants
>
> Signed-off-by: John Cox <jc at kynesim.co.uk>
> ---
> libavfilter/aarch64/vf_bwdif_neon.S | 53 +++++++++++++++++++++++++++++
> 1 file changed, 53 insertions(+)
>
> diff --git a/libavfilter/aarch64/vf_bwdif_neon.S b/libavfilter/aarch64/vf_bwdif_neon.S
> index 639ab22998..c2f5eb1f73 100644
> --- a/libavfilter/aarch64/vf_bwdif_neon.S
> +++ b/libavfilter/aarch64/vf_bwdif_neon.S
> @@ -23,3 +23,56 @@
>
> #include "libavutil/aarch64/asm.S"
>
> +// Space taken on the stack by an int (32-bit)
> +#ifdef __APPLE__
> +.set    SP_INT, 4
> +#else
> +.set    SP_INT, 8
> +#endif

Ok I guess this works and doesn't require excessive ifdefs. It can end up 
brittle though, but I guess this form can be tolerable.

// Martin