anv/pipeline: lower constant initializers on output variables earlier

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_vert
dEQP-VK.spirv_assembly.instruction.graphics.variable_init.output_frag

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>

diff --git a/src/intel/vulkan/anv_pipeline.c b/src/intel/vulkan/anv_pipeline.c
index 48eefe828a7559c4418745e83f8235304aa48fe4..e16a7a199403bc8f95b4d24a129055c44ae988fb 100644 (file)
--- a/src/intel/vulkan/anv_pipeline.c
+++ b/src/intel/vulkan/anv_pipeline.c
@@ -179,6 +179,11 @@ anv_shader_compile_to_nir(struct anv_pipeline *pipeline,
    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);