[Mesa-dev] [PATCH 1/5] i965/fs: Set force_writemask_all on shader_time instructions.

[Matt Turner]

On Sun, Mar 8, 2015 at 1:08 AM, Kenneth Graunke <kenneth at whitecape.org> wrote:
> These computations don't have anything to do with the currently
> executing channels, so they should use force_writemask_all.
>
> This fixes assert failures.
>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=86974
> Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
> Cc: mesa-stable at lists.freedesktop.org
> ---
>  src/mesa/drivers/dri/i965/brw_fs.cpp | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
> index d6acc23..45a5793 100644
> --- a/src/mesa/drivers/dri/i965/brw_fs.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
> @@ -759,18 +759,23 @@ fs_visitor::emit_shader_time_end()
>     reset.set_smear(2);
>     fs_inst *test = emit(AND(reg_null_d, reset, fs_reg(1u)));
>     test->conditional_mod = BRW_CONDITIONAL_Z;
> +   test->force_writemask_all = true;
>     emit(IF(BRW_PREDICATE_NORMAL));
>
>     fs_reg start = shader_start_time;
>     start.negate = true;
>     fs_reg diff = fs_reg(GRF, alloc.allocate(1), BRW_REGISTER_TYPE_UD, 1);
> -   emit(ADD(diff, start, shader_end_time));
> +   fs_inst *add = ADD(diff, start, shader_end_time);
> +   add->force_writemask_all = true;
> +   emit(add);

Emit returns a pointer to the instruction it emitted, so you can cut
one line by wrapping the ADD with emit().

Either way's fine.