[Mesa-dev] [PATCH] anv: Move nir_lower_wpos_center after dead variable elimination.

[Timothy Arceri]

On Wed, 2017-01-11 at 16:09 -0800, Kenneth Graunke wrote:
> When multiple shader stages exist in the same SPIR-V module, we
> compile
> all entry points and their inputs/outputs, then dead code eliminate
> the
> ones not related to the specific entry point later.
> 
> nir_lower_wpos_center was being run prior to eliminating those random
> other variables, which made it trip up, thinking it found
> gl_FragCoord
> when it actually found something else like gl_PerVertex[3].
> 
> Fixes dEQP-VK.spirv_assembly.instruction.graphics.module.same_module.
> 
> Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>

Reviewed-by: Timothy Arceri <timothy.arceri at collabora.com>

> ---
>  src/intel/vulkan/anv_pipeline.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/src/intel/vulkan/anv_pipeline.c
> b/src/intel/vulkan/anv_pipeline.c
> index 6c939b071da..7d939ebabe9 100644
> --- a/src/intel/vulkan/anv_pipeline.c
> +++ b/src/intel/vulkan/anv_pipeline.c
> @@ -139,9 +139,6 @@ anv_shader_compile_to_nir(struct anv_device
> *device,
>  
>     free(spec_entries);
>  
> -   if (stage == MESA_SHADER_FRAGMENT)
> -      NIR_PASS_V(nir, nir_lower_wpos_center);
> -
>     /* We have to lower away local constant initializers right before
> we
>      * inline functions.  That way they get properly initialized at
> the top
>      * of the function and not at the top of its caller.
> @@ -161,6 +158,9 @@ anv_shader_compile_to_nir(struct anv_device
> *device,
>     NIR_PASS_V(nir, nir_remove_dead_variables,
>                nir_var_shader_in | nir_var_shader_out |
> nir_var_system_value);
>  
> +   if (stage == MESA_SHADER_FRAGMENT)
> +      NIR_PASS_V(nir, nir_lower_wpos_center);
> +
>     /* Now that we've deleted all but the main function, we can go
> ahead and
>      * lower the rest of the constant initializers.
>      */