Module: Mesa Branch: master Commit: 461a5c899c08064467abb635536381a5a5659280 URL: http://cgit.freedesktop.org/mesa/mesa/commit/?id=461a5c899c08064467abb635536381a5a5659280
Author: Ian Romanick <ian.d.roman...@intel.com> Date: Tue Jun 5 15:04:24 2018 -0700 glsl: Don't copy propagate from SSBO or shared variables either Since SSBOs can be written by other GPU threads, copy propagating a read can cause the value to magically change. SSBO reads are also very expensive, so doing it twice will be slower. Haswell, Broadwell, and Skylake had similar results. (Skylake shown) total instructions in shared programs: 14399120 -> 14399119 (<.01%) instructions in affected programs: 684 -> 683 (-0.15%) helped: 1 HURT: 0 total cycles in shared programs: 532978931 -> 532973113 (<.01%) cycles in affected programs: 530484 -> 524666 (-1.10%) helped: 1 HURT: 0 Signed-off-by: Ian Romanick <ian.d.roman...@intel.com> Reviewed-by: Caio Marcelo de Oliveira Filho <caio.olive...@intel.com> Cc: mesa-sta...@lists.freedesktop.org Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=106774 --- src/compiler/glsl/opt_copy_propagation.cpp | 2 ++ 1 file changed, 2 insertions(+) diff --git a/src/compiler/glsl/opt_copy_propagation.cpp b/src/compiler/glsl/opt_copy_propagation.cpp index 6220aa86da..206dffe4f1 100644 --- a/src/compiler/glsl/opt_copy_propagation.cpp +++ b/src/compiler/glsl/opt_copy_propagation.cpp @@ -347,6 +347,8 @@ ir_copy_propagation_visitor::add_copy(ir_assignment *ir) if (lhs_var != NULL && rhs_var != NULL && lhs_var != rhs_var) { if (lhs_var->data.mode != ir_var_shader_storage && lhs_var->data.mode != ir_var_shader_shared && + rhs_var->data.mode != ir_var_shader_storage && + rhs_var->data.mode != ir_var_shader_shared && lhs_var->data.precise == rhs_var->data.precise) { _mesa_hash_table_insert(acp, lhs_var, rhs_var); } _______________________________________________ mesa-commit mailing list mesa-commit@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-commit
