[vlc-devel] [PATCH] display: avoid using memset in vout_display_PlacePicture()

[Steve Lhomme]

On 2020-08-21 13:46, Rémi Denis-Courmont wrote:
> Hi,
> 
> First, that's a rather dubious optimization. Compilers know how to 
> inline a fixed-size memset(), and you end up with one more branch with 
> this patch.

OK. I'm surprised a compiler could optimize a memset but not a set to { 
0 } of a structure.

> It doesn't make the code any clearer either.

If you end up changing the type of *place you may not notice. But it's 
really splitting hairs.

> Le 21 août 2020 10:19:24 GMT+02:00, Steve Lhomme <robux4 at ycbcr.xyz> a 
> écrit :
> 
>     It's only needed when the display has no dimension yet. The rest of the time
>     we fill all (4) fields of the vout_display_place_t structure.
>     ------------------------------------------------------------------------
>       src/video_output/display.c | 4 +++-
>       1 file changed, 3 insertions(+), 1 deletion(-)
> 
>     diff --git a/src/video_output/display.c b/src/video_output/display.c
>     index 8fd444168d0..84284e8f41d 100644
>     --- a/src/video_output/display.c
>     +++ b/src/video_output/display.c
>     @@ -150,9 +150,11 @@ void vout_display_PlacePicture(vout_display_place_t *place,
>           assert(cfg->window_props.width == 0 && cfg->window_props.height == 0);
>       
>           /* */
>     -    memset(place, 0, sizeof(*place));
>           if (cfg->display.width == 0 || cfg->display.height == 0)
>     +    {
>     +        *place = (vout_display_place_t) { 0 };
>               return;
>     +    }
>       
>           /* */
>           unsigned display_width;
> 
> 
> -- 
> Envoyé de mon appareil Android avec Courriel K-9 Mail. Veuillez excuser 
> ma brièveté.
> 
> _______________________________________________
> vlc-devel mailing list
> To unsubscribe or modify your subscription options:
> https://mailman.videolan.org/listinfo/vlc-devel
>