[Mesa-dev] [PATCH] radv: lower constant initializers on output variables earlier

[Samuel Pitoiset]

Reviewed-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>

On 03/19/2018 05:30 AM, Dave Airlie wrote:
> From: Dave Airlie <airlied at redhat.com>
> 
> If a shader only writes to an output via a constant initializer we
> need to lower it before we call nir_remove_dead_variables so that
> this pass sees the stores from the initializer and doesn't kill the
> output.
> 
> Fixes test failures in new work-in-progress CTS tests:
> dEQP-VK.spirv_assembly.instruction.graphics.variable_init.output.float
> 
> This is ported from anv:
> 99b57daf4a anv/pipeline: lower constant initializers on output variables earlier
> from Iago Toral Quiroga <itoral at igalia.com>
> ---
>   src/amd/vulkan/radv_shader.c | 5 +++++
>   1 file changed, 5 insertions(+)
> 
> diff --git a/src/amd/vulkan/radv_shader.c b/src/amd/vulkan/radv_shader.c
> index 180b427a442..ac577c36e9f 100644
> --- a/src/amd/vulkan/radv_shader.c
> +++ b/src/amd/vulkan/radv_shader.c
> @@ -244,6 +244,11 @@ radv_shader_compile_to_nir(struct radv_device *device,
>   		assert(exec_list_length(&nir->functions) == 1);
>   		entry_point->name = ralloc_strdup(entry_point, "main");
>   
> +		/* Make sure we lower constant initializers on output variables so that
> +		 * nir_remove_dead_variables below sees the corresponding stores
> +		 */
> +		NIR_PASS_V(nir, nir_lower_constant_initializers, nir_var_shader_out);
> +
>   		NIR_PASS_V(nir, nir_remove_dead_variables,
>   		           nir_var_shader_in | nir_var_shader_out | nir_var_system_value);
>   
>