[FFmpeg-devel] [PATCH 06/10] avfilter/avgblur_vulkan: call av_vkfmt_from_pixfmt only one time

[Andreas Rheinhardt]

Wu Jianhua:
> There is a loop in av_vkfmt_from_pixfmt. And, even though some
> compilers will optimize it when the optimization option is on, to
> consider more situations, just call the function only one time here.
> 
> Signed-off-by: Wu Jianhua <jianhua.wu at intel.com>
> ---

What compilers optimize this? And how? After all, this function is not
marked as const.

>  libavfilter/vf_avgblur_vulkan.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
> 
> diff --git a/libavfilter/vf_avgblur_vulkan.c b/libavfilter/vf_avgblur_vulkan.c
> index 243e932f35..080a8b1b63 100644
> --- a/libavfilter/vf_avgblur_vulkan.c
> +++ b/libavfilter/vf_avgblur_vulkan.c
> @@ -210,6 +210,10 @@ static int process_frames(AVFilterContext *avctx, AVFrame *out_f, AVFrame *tmp_f
>      AVVkFrame *in = (AVVkFrame *)in_f->data[0];
>      AVVkFrame *tmp = (AVVkFrame *)tmp_f->data[0];
>      AVVkFrame *out = (AVVkFrame *)out_f->data[0];
> +
> +    const VkFormat *input_formats = av_vkfmt_from_pixfmt(s->vkctx.input_format);
> +    const VkFormat *output_formats = av_vkfmt_from_pixfmt(s->vkctx.output_format);
> +
>      int planes = av_pix_fmt_count_planes(s->vkctx.output_format);
>  
>      /* Update descriptors and init the exec context */
> @@ -219,17 +223,17 @@ static int process_frames(AVFilterContext *avctx, AVFrame *out_f, AVFrame *tmp_f
>      for (int i = 0; i < planes; i++) {
>          RET(ff_vk_create_imageview(avctx, s->exec, &s->input_images[i].imageView,
>                                     in->img[i],
> -                                   av_vkfmt_from_pixfmt(s->vkctx.input_format)[i],
> +                                   input_formats[i],
>                                     ff_comp_identity_map));
>  
>          RET(ff_vk_create_imageview(avctx, s->exec, &s->tmp_images[i].imageView,
>                                     tmp->img[i],
> -                                   av_vkfmt_from_pixfmt(s->vkctx.output_format)[i],
> +                                   output_formats[i],
>                                     ff_comp_identity_map));
>  
>          RET(ff_vk_create_imageview(avctx, s->exec, &s->output_images[i].imageView,
>                                     out->img[i],
> -                                   av_vkfmt_from_pixfmt(s->vkctx.output_format)[i],
> +                                   output_formats[i],
>                                     ff_comp_identity_map));
>  
>          s->input_images[i].imageLayout = VK_IMAGE_LAYOUT_SHADER_READ_ONLY_OPTIMAL;
>