+
+ /* Bitmask indicating which coordinate attribute should be used for
+ * comparison to each clipping plane. A 0 indicates that VARYING_SLOT_POS
+ * should be used, because it's one of the fixed +/- x/y/z planes that
+ * constitute the bounds of the view volume. A 1 indicates that
+ * VARYING_SLOT_CLIP_VERTEX should be used (if available) since it's a user-
+ * defined clipping plane.
+ */
+ struct brw_reg vertex_src_mask;
+
+ /* Offset into the vertex of the current plane's clipdistance value */
+ struct brw_reg clipdistance_offset;