From 34ab9b0947cdc1f035ca8379a92677b66ec604a5 Mon Sep 17 00:00:00 2001 From: Timothy Arceri Date: Tue, 24 Jan 2017 14:07:04 +1100 Subject: [PATCH] glsl: lower constant arrays to uniform arrays before optimisation loop Previously the constant array would not get copy propagated until the backend did its GLSL IR opt loop. I plan on removing that from i965 shortly which caused huge regressions in Deus-ex and Tomb Raider which have large constant arrays. Moving lowering before the opt loop in the GLSL linker fixes this and unexpectedly improves some compute shaders also. shader-db results BDW: instructions helped: shaders/closed/steam/deus-ex-mankind-divided/374.shader_test CS SIMD16: 204 -> 194 (-4.90%) instructions helped: shaders/closed/steam/deus-ex-mankind-divided/318.shader_test CS SIMD8: 1010 -> 741 (-26.63%) instructions helped: shaders/closed/steam/deus-ex-mankind-divided/144.shader_test CS SIMD8: 542 -> 385 (-28.97%) cycles helped: shaders/closed/steam/deus-ex-mankind-divided/318.shader_test CS SIMD8: 1831382 -> 1818492 (-0.70%) cycles helped: shaders/closed/steam/deus-ex-mankind-divided/144.shader_test CS SIMD8: 216238 -> 206180 (-4.65%) cycles helped: shaders/closed/steam/deus-ex-mankind-divided/374.shader_test CS SIMD16: 18484 -> 16644 (-9.95%) total instructions in shared programs: 13060313 -> 13059877 (-0.00%) instructions in affected programs: 1756 -> 1320 (-24.83%) helped: 3 HURT: 0 total cycles in shared programs: 256586698 -> 256561910 (-0.01%) cycles in affected programs: 2066104 -> 2041316 (-1.20%) helped: 3 HURT: 0 V3: only call the opt loop if lowering progressed (Suggested by Eric) V2: call opts before and after lowering (Suggested by Ken) Reviewed-by: Eric Anholt --- src/compiler/glsl/linker.cpp | 39 ++++++++++++++++++++++++------------ 1 file changed, 26 insertions(+), 13 deletions(-) diff --git a/src/compiler/glsl/linker.cpp b/src/compiler/glsl/linker.cpp index dafa39d438d..b768a6e5285 100644 --- a/src/compiler/glsl/linker.cpp +++ b/src/compiler/glsl/linker.cpp @@ -4608,6 +4608,24 @@ link_varyings_and_uniforms(unsigned first, unsigned last, return true; } +static void +linker_optimisation_loop(struct gl_context *ctx, exec_list *ir, + unsigned stage) +{ + if (ctx->Const.GLSLOptimizeConservatively) { + /* Run it just once. */ + do_common_optimization(ir, true, false, + &ctx->Const.ShaderCompilerOptions[stage], + ctx->Const.NativeIntegers); + } else { + /* Repeat it until it stops making changes. */ + while (do_common_optimization(ir, true, false, + &ctx->Const.ShaderCompilerOptions[stage], + ctx->Const.NativeIntegers)) + ; + } +} + void link_shaders(struct gl_context *ctx, struct gl_shader_program *prog) { @@ -4882,20 +4900,15 @@ link_shaders(struct gl_context *ctx, struct gl_shader_program *prog) lower_tess_level(prog->_LinkedShaders[i]); } - if (ctx->Const.GLSLOptimizeConservatively) { - /* Run it just once. */ - do_common_optimization(prog->_LinkedShaders[i]->ir, true, false, - &ctx->Const.ShaderCompilerOptions[i], - ctx->Const.NativeIntegers); - } else { - /* Repeat it until it stops making changes. */ - while (do_common_optimization(prog->_LinkedShaders[i]->ir, true, false, - &ctx->Const.ShaderCompilerOptions[i], - ctx->Const.NativeIntegers)) - ; - } + /* Call opts before lowering const arrays to uniforms so we can const + * propagate any elements accessed directly. + */ + linker_optimisation_loop(ctx, prog->_LinkedShaders[i]->ir, i); + + /* Call opts after lowering const arrays to copy propagate things. */ + if (lower_const_arrays_to_uniforms(prog->_LinkedShaders[i]->ir, i)) + linker_optimisation_loop(ctx, prog->_LinkedShaders[i]->ir, i); - lower_const_arrays_to_uniforms(prog->_LinkedShaders[i]->ir, i); propagate_invariance(prog->_LinkedShaders[i]->ir); } -- 2.30.2