[Mesa-dev] [PATCH 7/7] radv: enable nir component packing

[Timothy Arceri]

SaschaWillems Vulkan demo tessellation:

~4300fps -> ~4800fps
---
 src/amd/vulkan/radv_pipeline.c | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/src/amd/vulkan/radv_pipeline.c b/src/amd/vulkan/radv_pipeline.c
index d0e47383d7..69bda152e2 100644
--- a/src/amd/vulkan/radv_pipeline.c
+++ b/src/amd/vulkan/radv_pipeline.c
@@ -1760,20 +1760,21 @@ void radv_create_shaders(struct radv_pipeline *pipeline,
 	}
 
 	if (!modules[MESA_SHADER_FRAGMENT] && !modules[MESA_SHADER_COMPUTE]) {
 		nir_builder fs_b;
 		nir_builder_init_simple_shader(&fs_b, NULL, MESA_SHADER_FRAGMENT, NULL);
 		fs_b.shader->info.name = ralloc_strdup(fs_b.shader, "noop_fs");
 		fs_m.nir = fs_b.shader;
 		modules[MESA_SHADER_FRAGMENT] = &fs_m;
 	}
 
+	int prev = -1;
 	for (unsigned i = 0; i < MESA_SHADER_STAGES; ++i) {
 		const VkPipelineShaderStageCreateInfo *stage = pStages[i];
 
 		if (!modules[i])
 			continue;
 
 		nir[i] = radv_shader_compile_to_nir(device, modules[i],
 						    stage ? stage->pName : "main", i,
 						    stage ? stage->pSpecializationInfo : NULL);
 		pipeline->active_stages |= mesa_to_vk_shader_stage(i);
@@ -1790,20 +1791,32 @@ void radv_create_shaders(struct radv_pipeline *pipeline,
 
 			if (i != first)
 				mask = mask | nir_var_shader_in;
 
 			if (i != last)
 				mask = mask | nir_var_shader_out;
 
 			nir_lower_io_to_scalar_early(nir[i], mask);
 			radv_optimize_nir(nir[i]);
 		}
+
+		if (prev != -1) {
+			nir_compact_varyings(nir[prev], nir[i], true);
+
+			/* TODO: In future nir_compact_varyings() should update the varying
+			 * input/output mask to reflect the packing it has just done. However
+			 * until we have an array/matrix splitting pass we would just be
+			 * duplicating the complex partial marking code in nir_gather_info().
+			 */
+			nir_shader_gather_info(nir[i], nir_shader_get_entrypoint(nir[i]));
+		}
+		prev = i;
 	}
 
 	if (nir[MESA_SHADER_TESS_CTRL]) {
 		/* TODO: This is no longer used as a key we should refactor this */
 		if (keys)
 			keys[MESA_SHADER_TESS_CTRL].tcs.primitive_mode = nir[MESA_SHADER_TESS_EVAL]->info.tess.primitive_mode;
 
 		keys[MESA_SHADER_TESS_CTRL].tcs.tes_reads_tess_factors = !!(nir[MESA_SHADER_TESS_EVAL]->info.inputs_read & (VARYING_BIT_TESS_LEVEL_INNER | VARYING_BIT_TESS_LEVEL_OUTER));
 		nir_lower_tes_patch_vertices(nir[MESA_SHADER_TESS_EVAL], nir[MESA_SHADER_TESS_CTRL]->info.tess.tcs_vertices_out);
 	}
-- 
2.13.6