From 49503ae74e2634ebd2e0d3caa36c25ed99e19b9c Mon Sep 17 00:00:00 2001 From: Connor Abbott Date: Mon, 2 Sep 2019 11:57:34 +0200 Subject: [PATCH] st/nir: Don't lower indirects when linking I believe this was stuck here early because otherwise nir_opt_copy_prop_vars could undo what lower_io_to_temporaries does. However that has since been fixed. Also, we now use scratch for large variables so the comment is stale. On radeonsi these are the shader-db results: Totals: SGPRS: 3955968 -> 3955968 (0.00 %) VGPRS: 2220208 -> 2220220 (0.00 %) Spilled SGPRs: 11387 -> 11387 (0.00 %) Spilled VGPRs: 97 -> 97 (0.00 %) Private memory VGPRs: 2528 -> 2528 (0.00 %) Scratch size: 2656 -> 2656 (0.00 %) dwords per thread Code Size: 76002108 -> 76002204 (0.00 %) bytes LDS: 740 -> 740 (0.00 %) blocks Max Waves: 772779 -> 772776 (-0.00 %) Wait states: 0 -> 0 (0.00 %) Totals from affected shaders: SGPRS: 176 -> 176 (0.00 %) VGPRS: 144 -> 156 (8.33 %) Spilled SGPRs: 0 -> 0 (0.00 %) Spilled VGPRs: 0 -> 0 (0.00 %) Private memory VGPRs: 0 -> 0 (0.00 %) Scratch size: 0 -> 0 (0.00 %) dwords per thread Code Size: 12104 -> 12200 (0.79 %) bytes LDS: 0 -> 0 (0.00 %) blocks Max Waves: 28 -> 25 (-10.71 %) Wait states: 0 -> 0 (0.00 %) The few small regressions are due to nir_opt_large_constants kicking in when indirect lowering happens to result in smaller code after optimization since the array is very simple. Reviewed-by: Kenneth Graunke Reviewed-by: Timothy Arceri --- src/mesa/state_tracker/st_glsl_to_nir.cpp | 18 +----------------- 1 file changed, 1 insertion(+), 17 deletions(-) diff --git a/src/mesa/state_tracker/st_glsl_to_nir.cpp b/src/mesa/state_tracker/st_glsl_to_nir.cpp index 081f85edf53..4585455c856 100644 --- a/src/mesa/state_tracker/st_glsl_to_nir.cpp +++ b/src/mesa/state_tracker/st_glsl_to_nir.cpp @@ -596,26 +596,10 @@ st_nir_link_shaders(nir_shader **producer, nir_shader **consumer, bool scalar) NIR_PASS_V(*producer, nir_lower_global_vars_to_local); NIR_PASS_V(*consumer, nir_lower_global_vars_to_local); - /* The backend might not be able to handle indirects on - * temporaries so we need to lower indirects on any of the - * varyings we have demoted here. - * - * TODO: radeonsi shouldn't need to do this, however LLVM isn't - * currently smart enough to handle indirects without causing excess - * spilling causing the gpu to hang. - * - * See the following thread for more details of the problem: - * https://lists.freedesktop.org/archives/mesa-dev/2017-July/162106.html - */ - nir_variable_mode indirect_mask = nir_var_function_temp; - - NIR_PASS_V(*producer, nir_lower_indirect_derefs, indirect_mask); - NIR_PASS_V(*consumer, nir_lower_indirect_derefs, indirect_mask); - st_nir_opts(*producer, scalar); st_nir_opts(*consumer, scalar); - /* Lowering indirects can cause varying to become unused. + /* Optimizations can cause varyings to become unused. * nir_compact_varyings() depends on all dead varyings being removed so * we need to call nir_remove_dead_variables() again here. */ -- 2.30.2