[FFmpeg-devel] [PATCH v2 5/5] aarch64: Add Windows runtime detection of the dotprod instructions

[James Zern]

On Tue, May 30, 2023 at 5:31 AM Martin Storsjö <martin at martin.st> wrote:
>
> For Windows, there's no publicly defined constant for checking for
> the i8mm extension yet.
> ---
>  libavutil/aarch64/cpu.c | 10 ++++++++++
>  1 file changed, 10 insertions(+)
>
> diff --git a/libavutil/aarch64/cpu.c b/libavutil/aarch64/cpu.c
> index ffb00f6dd2..4b97530240 100644
> --- a/libavutil/aarch64/cpu.c
> +++ b/libavutil/aarch64/cpu.c
> @@ -94,6 +94,16 @@ static int detect_flags(void)
>      return flags;
>  }
>
> +#elif defined(_WIN32)
> +#include <windows.h>
> +
> +static int detect_flags(void)
> +{
> +    int flags = 0;
> +    if (IsProcessorFeaturePresent(PF_ARM_V82_DP_INSTRUCTIONS_AVAILABLE))

I think this requires a recent Windows SDK, is compatibility a concern?
lgtm otherwise.