intel/compiler: store the FS inputs in WM prog data

Store the fragment shader inputs in the program data so we can use them
later when required without needing the NIR shader.

Cc: mesa-stable@lists.freedesktop.org
Signed-off-by: Juan A. Suarez Romero <jasuarez@igalia.com>
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Ivan Briano <ivan.briano@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/2010>

src/intel/compiler/brw_compiler.h

@@ -780,6 +780,11 @@ struct brw_wm_prog_data {
     */
    uint32_t flat_inputs;
 
+   /**
+    * The FS inputs
+    */
+   uint64_t inputs;
+
    /* Mapping of VUE slots to interpolation modes.
     * Used by the Gen4-5 clip/sf/wm stages.
     */

src/intel/compiler/brw_fs.cpp

@@ -1748,6 +1748,7 @@ calculate_urb_setup(const struct gen_device_info *devinfo,
    }
 
    prog_data->num_varying_inputs = urb_next;
+   prog_data->inputs = nir->info.inputs_read;
 
    brw_compute_urb_setup_index(prog_data);
 }