+ vue_map->num_per_vertex_slots = 0;
+ vue_map->num_per_patch_slots = 0;
+}
+
+/**
+ * Compute the VUE map for tessellation control shader outputs and
+ * tessellation evaluation shader inputs.
+ */
+void
+brw_compute_tess_vue_map(struct brw_vue_map *vue_map,
+ GLbitfield64 vertex_slots,
+ GLbitfield patch_slots)
+{
+ /* I don't think anything actually uses this... */
+ vue_map->slots_valid = vertex_slots;
+
+ vertex_slots &= ~(VARYING_BIT_TESS_LEVEL_OUTER |
+ VARYING_BIT_TESS_LEVEL_INNER);
+
+ /* Make sure that the values we store in vue_map->varying_to_slot and
+ * vue_map->slot_to_varying won't overflow the signed chars that are used
+ * to store them. Note that since vue_map->slot_to_varying sometimes holds
+ * values equal to VARYING_SLOT_TESS_MAX , we need to ensure that
+ * VARYING_SLOT_TESS_MAX is <= 127, not 128.
+ */
+ STATIC_ASSERT(VARYING_SLOT_TESS_MAX <= 127);
+
+ for (int i = 0; i < VARYING_SLOT_TESS_MAX ; ++i) {
+ vue_map->varying_to_slot[i] = -1;
+ vue_map->slot_to_varying[i] = BRW_VARYING_SLOT_PAD;
+ }
+
+ int slot = 0;
+
+ /* The first 8 DWords are reserved for the "Patch Header".
+ *
+ * VARYING_SLOT_TESS_LEVEL_OUTER / INNER live here, but the exact layout
+ * depends on the domain type. They might not be in slots 0 and 1 as
+ * described here, but pretending they're separate allows us to uniquely
+ * identify them by distinct slot locations.
+ */
+ assign_vue_slot(vue_map, VARYING_SLOT_TESS_LEVEL_INNER, slot++);
+ assign_vue_slot(vue_map, VARYING_SLOT_TESS_LEVEL_OUTER, slot++);
+
+ /* first assign per-patch varyings */
+ while (patch_slots != 0) {
+ const int varying = ffsll(patch_slots) - 1;
+ if (vue_map->varying_to_slot[varying + VARYING_SLOT_PATCH0] == -1) {
+ assign_vue_slot(vue_map, varying + VARYING_SLOT_PATCH0, slot++);
+ }
+ patch_slots &= ~BITFIELD64_BIT(varying);
+ }
+
+ /* apparently, including the patch header... */
+ vue_map->num_per_patch_slots = slot;
+
+ /* then assign per-vertex varyings for each vertex in our patch */
+ while (vertex_slots != 0) {
+ const int varying = ffsll(vertex_slots) - 1;
+ if (vue_map->varying_to_slot[varying] == -1) {
+ assign_vue_slot(vue_map, varying, slot++);
+ }
+ vertex_slots &= ~BITFIELD64_BIT(varying);
+ }
+
+ vue_map->num_per_vertex_slots = slot - vue_map->num_per_patch_slots;
+ vue_map->num_slots = slot;