[FFmpeg-devel] [PATCH] avcodec/h264_levels, h265_profile_level: Avoid relocations

[Andreas Rheinhardt]

Andreas Rheinhardt:
> H.264 and H.265 levels' names are usually of the form "x" or "x.y"
> with x and y being single digits; the one exception are the H.264 1b
> levels. All of those levels' names fit into a char[4] and it is likely
> that this future levels will do so, too.
> 
> Therefore this commit changes the H26(4|5)LevelDescriptor structures
> to use such a char [4] instead of a pointer to a const char. This makes
> the structures smaller (when sizeof(char*) == 8) and avoids relocations,
> thereby moving the corresponding arrays from .data.rel.ro into .rodata.
> 
> Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
> ---
>  libavcodec/h264_levels.h        | 2 +-
>  libavcodec/h265_profile_level.h | 2 +-
>  2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/libavcodec/h264_levels.h b/libavcodec/h264_levels.h
> index 6bba2e8624..310d79e51a 100644
> --- a/libavcodec/h264_levels.h
> +++ b/libavcodec/h264_levels.h
> @@ -23,7 +23,7 @@
>  #include <stdint.h>
>  
>  typedef struct H264LevelDescriptor {
> -    const char *name;
> +    char        name[4];    // Large enough for all current levels like "4.1"
>      uint8_t     level_idc;
>      uint8_t     constraint_set3_flag;
>      uint32_t    max_mbps;
> diff --git a/libavcodec/h265_profile_level.h b/libavcodec/h265_profile_level.h
> index f1a11f51dc..cd30ac5c50 100644
> --- a/libavcodec/h265_profile_level.h
> +++ b/libavcodec/h265_profile_level.h
> @@ -25,7 +25,7 @@
>  
>  
>  typedef struct H265LevelDescriptor {
> -    const char *name;
> +    char        name[4];    // Large enough for all current levels like "4.1"
>      uint8_t     level_idc;
>  
>      // Table A.6.
> 
Will apply tomorrow unless there are objections.

- Andreas