intel: emit is_indexed_draw in the same VE than gl_DrawID

The Vertex Elements are now:
* VE 1: <BaseVertex/firstvertex, BaseInstance, VertexID, InstanceID>
* VE 2: <DrawID, is-indexed-draw, 0, 0>

VE1 is it kept as it was before, VE2 additionally contains the new
system value.

Reviewed-by: Jason Ekstrand <[email protected]>

1 files changed, 8 insertions, 3 deletions

diff --git a/src/intel/compiler/brw_nir.c b/src/intel/compiler/brw_nir.c
index 16b0d86814f..a624deb6d2a 100644
--- a/src/intel/compiler/brw_nir.c
+++ b/src/intel/compiler/brw_nir.c
@@ -266,6 +266,7 @@ brw_nir_lower_vs_inputs(nir_shader *nir,
             case nir_intrinsic_load_base_instance:
             case nir_intrinsic_load_vertex_id_zero_base:
             case nir_intrinsic_load_instance_id:
+            case nir_intrinsic_load_is_indexed_draw:
             case nir_intrinsic_load_draw_id: {
                b.cursor = nir_after_instr(&intrin->instr);
 
@@ -293,11 +294,15 @@ brw_nir_lower_vs_inputs(nir_shader *nir,
                   nir_intrinsic_set_component(load, 3);
                   break;
                case nir_intrinsic_load_draw_id:
-                  /* gl_DrawID is stored right after gl_VertexID and friends
-                   * if any of them exist.
+               case nir_intrinsic_load_is_indexed_draw:
+                  /* gl_DrawID and IsIndexedDraw are stored right after
+                   * gl_VertexID and friends if any of them exist.
                    */
                   nir_intrinsic_set_base(load, num_inputs + has_sgvs);
-                  nir_intrinsic_set_component(load, 0);
+                  if (intrin->intrinsic == nir_intrinsic_load_draw_id)
+                     nir_intrinsic_set_component(load, 0);
+                  else
+                     nir_intrinsic_set_component(load, 1);
                   break;
                default:
                   unreachable("Invalid system value intrinsic");