Gallium drivers should never see nir_var_uniform because gallium lowers
regular uniforms to a UBO.  No GL driver should ever see either
nir_var_mem_shared because that's lowered in GLSL IR.
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5418>
       .ballot_bit_size = 32,
    };
 
-   NIR_PASS_V(nir, nir_lower_io, nir_var_all, type_size, (nir_lower_io_options)0);
+   NIR_PASS_V(nir, nir_lower_io,
+              (nir_variable_mode)(nir_var_shader_in | nir_var_shader_out),
+              type_size, (nir_lower_io_options)0);
    NIR_PASS_V(nir, nir_lower_subgroups, &subgroup_options);
    NIR_PASS_V(nir, nir_lower_regs_to_ssa);
    NIR_PASS_V(nir, nir_lower_load_const_to_scalar);