[Mesa-dev] [PATCH] radv: Add NIR loop unrolling.

[Bas Nieuwenhuizen]

Not much effect on dota2/talos, but positive on deferred.

Signed-off-by: Bas Nieuwenhuizen <basni at google.com>
---
 src/amd/vulkan/radv_pipeline.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/amd/vulkan/radv_pipeline.c b/src/amd/vulkan/radv_pipeline.c
index d6989137a55..7340675915f 100644
--- a/src/amd/vulkan/radv_pipeline.c
+++ b/src/amd/vulkan/radv_pipeline.c
@@ -61,6 +61,7 @@ static const struct nir_shader_compiler_options nir_options = {
 	.lower_unpack_unorm_4x8 = true,
 	.lower_extract_byte = true,
 	.lower_extract_word = true,
+	.max_unroll_iterations = 32
 };
 
 VkResult radv_CreateShaderModule(
@@ -152,6 +153,12 @@ radv_optimize_nir(struct nir_shader *shader)
                 NIR_PASS(progress, shader, nir_copy_prop);
                 NIR_PASS(progress, shader, nir_opt_remove_phis);
                 NIR_PASS(progress, shader, nir_opt_dce);
+                if (nir_opt_trivial_continues(shader)) {
+                        progress = true;
+                        NIR_PASS(progress, shader, nir_copy_prop);
+                        NIR_PASS(progress, shader, nir_opt_dce);
+                }
+                NIR_PASS(progress, shader, nir_opt_if);
                 NIR_PASS(progress, shader, nir_opt_dead_cf);
                 NIR_PASS(progress, shader, nir_opt_cse);
                 NIR_PASS(progress, shader, nir_opt_peephole_select, 8);
@@ -159,6 +166,9 @@ radv_optimize_nir(struct nir_shader *shader)
                 NIR_PASS(progress, shader, nir_opt_constant_folding);
                 NIR_PASS(progress, shader, nir_opt_undef);
                 NIR_PASS(progress, shader, nir_opt_conditional_discard);
+                if (shader->options->max_unroll_iterations) {
+                        NIR_PASS(progress, shader, nir_opt_loop_unroll, 0);
+                }
         } while (progress);
 }
 
-- 
2.12.2