[Mesa-dev] [PATCH 21/23] i965: Implement gl_InvocationID.

[Kenneth Graunke]

It's stored in bits 31:27 of g1 (along with the URB handles).

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
---
 src/mesa/drivers/dri/i965/brw_fs_nir.cpp | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
index 774ce86..dda2c7c 100644
--- a/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs_nir.cpp
@@ -280,6 +280,18 @@ emit_system_values_block(nir_block *block, void *void_visitor)
             *reg = *v->emit_vs_system_value(SYSTEM_VALUE_INSTANCE_ID);
          break;
 
+      case nir_intrinsic_load_invocation_id:
+         assert(v->stage == MESA_SHADER_GEOMETRY);
+         reg = &v->nir_system_values[SYSTEM_VALUE_INVOCATION_ID];
+         if (reg->file == BAD_FILE) {
+            const fs_builder abld = v->bld.annotate("gl_InvocationID", NULL);
+            fs_reg g1(retype(brw_vec8_grf(1, 0), BRW_REGISTER_TYPE_UD));
+            fs_reg iid = abld.vgrf(BRW_REGISTER_TYPE_UD, 1);
+            abld.SHR(iid, g1, fs_reg(27u));
+            *reg = iid;
+         }
+         break;
+
       case nir_intrinsic_load_sample_pos:
          assert(v->stage == MESA_SHADER_FRAGMENT);
          reg = &v->nir_system_values[SYSTEM_VALUE_SAMPLE_POS];
@@ -1439,6 +1451,7 @@ fs_visitor::nir_emit_intrinsic(const fs_builder &bld, nir_intrinsic_instr *instr
    case nir_intrinsic_load_vertex_id_zero_base:
    case nir_intrinsic_load_base_vertex:
    case nir_intrinsic_load_instance_id:
+   case nir_intrinsic_load_invocation_id:
    case nir_intrinsic_load_sample_mask_in:
    case nir_intrinsic_load_sample_id: {
       gl_system_value sv = nir_system_value_from_intrinsic(instr->intrinsic);
-- 
2.5.3