[Mesa-dev] [PATCH 1/7] i965: Use 4 bits to store nr_userclip in brw_clip.h.

[Kenneth Graunke]

On 09/25/2011 09:21 AM, Paul Berry wrote:
> Since the i965 driver supports 8 clipping planes now, we need 4 bits
> to store the number of user clipping planes, not 3.
> 
> In theory this isn't strictly necessary, since brw_clip.h is only used
> on pre-GEN6, and pre-GEN6 only advertises support for 6 clipping
> planes, but it seems wise to err on the safe side.
> ---
>  src/mesa/drivers/dri/i965/brw_clip.h |    4 ++--
>  1 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/src/mesa/drivers/dri/i965/brw_clip.h b/src/mesa/drivers/dri/i965/brw_clip.h
> index 8647847..029270a 100644
> --- a/src/mesa/drivers/dri/i965/brw_clip.h
> +++ b/src/mesa/drivers/dri/i965/brw_clip.h
> @@ -44,7 +44,7 @@
>  struct brw_clip_prog_key {
>     GLbitfield64 attrs;
>     GLuint primitive:4;
> -   GLuint nr_userclip:3;
> +   GLuint nr_userclip:4;
>     GLuint do_flat_shading:1;
>     GLuint pv_first:1;
>     GLuint do_unfilled:1;
> @@ -55,7 +55,7 @@ struct brw_clip_prog_key {
>     GLuint copy_bfc_cw:1;
>     GLuint copy_bfc_ccw:1;
>     GLuint clip_mode:3;
> -   GLuint pad0:11;
> +   GLuint pad0:10;
>  
>     GLfloat offset_factor;
>     GLfloat offset_units;

pad0 is entirely pointless.  It makes sense to have these for hardware
structures, but for a hash table key...?  The compiler can't be -that-
dumb.  I'd just remove it.