From 3759a89ad358139ef981bd5d46261ee115762b94 Mon Sep 17 00:00:00 2001 From: Matt Turner Date: Fri, 22 Aug 2014 11:01:13 -0700 Subject: [PATCH] i965/fs: Eliminate null-dst instructions without side-effects. Reviewed-by: Kenneth Graunke --- .../drivers/dri/i965/brw_fs_dead_code_eliminate.cpp | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/src/mesa/drivers/dri/i965/brw_fs_dead_code_eliminate.cpp b/src/mesa/drivers/dri/i965/brw_fs_dead_code_eliminate.cpp index 81be4def30b..d66808bf45c 100644 --- a/src/mesa/drivers/dri/i965/brw_fs_dead_code_eliminate.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs_dead_code_eliminate.cpp @@ -85,6 +85,17 @@ fs_visitor::dead_code_eliminate() } } + if ((inst->opcode != BRW_OPCODE_IF && + inst->opcode != BRW_OPCODE_WHILE) && + inst->dst.is_null() && + !inst->has_side_effects() && + !inst->writes_flag() && + !inst->writes_accumulator) { + inst->opcode = BRW_OPCODE_NOP; + progress = true; + continue; + } + if (inst->dst.file == GRF) { if (!inst->is_partial_write()) { int var = live_intervals->var_from_reg(inst->dst); -- 2.30.2