[Mesa-dev] [PATCH] i965: disable NIR linking on HSW and below

[Iago Toral]

On Mon, 2017-11-06 at 10:31 +1100, Timothy Arceri wrote:
> Fixes: 379b24a40d3d "i965: make use of nir linking"
> 
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=103537
> ---
> 
> Jason's fixes referenced in the bug report help a little,
> however there are still issues with the vector backend and
> I don't have time to investigate right now so just disable it.
> 
>  src/mesa/drivers/dri/i965/brw_link.cpp | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/src/mesa/drivers/dri/i965/brw_link.cpp
> b/src/mesa/drivers/dri/i965/brw_link.cpp
> index 9019db56aa0..5cbfd85c05f 100644
> --- a/src/mesa/drivers/dri/i965/brw_link.cpp
> +++ b/src/mesa/drivers/dri/i965/brw_link.cpp
> @@ -272,8 +272,11 @@ brw_link_shader(struct gl_context *ctx, struct
> gl_shader_program *shProg)
>      * ensures that inter-shader outputs written to in an earlier
> stage
>      * are eliminated if they are (transitively) not used in a later
>      * stage.
> +    *
> +    * TODO: Look into Shader of Mordor regressions on HSW and enable

'Shadow of Mordor' :)

> this for
> +    * all platforms. See: https://bugs.freedesktop.org/show_bug.cgi?
> id=103537
>      */
> -    if (first != last) {
> +    if (first != last && brw->screen->devinfo.gen >= 8) {
>         int next = last;
>         for (int i = next - 1; i >= 0; i--) {
>            if (shProg->_LinkedShaders[i] == NULL)

'first' and 'last' are only used in this block so maybe we should not
even bother computing them if gen < 7?

Either way:
Reviewed-by: Iago Toral Quiroga <itoral at igalia.com>