nir: Add new GS intrinsics that maintain a count of emitted vertices.

This patch also introduces a lowering pass to convert the simple GS
intrinsics to the new ones.  See the comments above that for the
rationale behind the new intrinsics.

This should be useful for i965; it's a generic enough mechanism that I
could see other drivers potentially using it as well, so I don't feel
too bad about putting it in the generic code.

v2:
- Use nir_after_block_before_jump for the cursor (caught by Jason
  Ekstrand - I'd mistakenly used nir_after_block when rebasing this
  code onto the new NIR control flow API).
- Remove the old emit_vertex intrinsic at the end, rather than in
  the middle (requested by Jason).
- Use state->... directly rather than locals (requested by Jason).
- Report progress from nir_lower_gs_intrinsics() (requested by me).
- Remove "Authors:" section from file comment (requested by
  Michael Schellenberger Costa).

Signed-off-by: Kenneth Graunke <[email protected]>
Reviewed-by: Jason Ekstrand <[email protected]>

1 files changed, 2 insertions, 0 deletions

diff --git a/src/glsl/nir/nir.h b/src/glsl/nir/nir.h
index 619a363b540..4f45770e02d 100644
--- a/src/glsl/nir/nir.h
+++ b/src/glsl/nir/nir.h
@@ -1883,6 +1883,8 @@ void nir_lower_two_sided_color(nir_shader *shader);
 void nir_lower_atomics(nir_shader *shader);
 void nir_lower_to_source_mods(nir_shader *shader);
 
+bool nir_lower_gs_intrinsics(nir_shader *shader);
+
 bool nir_normalize_cubemap_coords(nir_shader *shader);
 
 void nir_live_variables_impl(nir_function_impl *impl);