From 38707e1478a4b6f4687c583d06fbd68e22900735 Mon Sep 17 00:00:00 2001 From: Ben Widawsky Date: Tue, 31 Mar 2015 15:49:42 -0700 Subject: [PATCH] i965/fs: Create a has_side_effects for fs_inst When an instruction has a side effect, it impacts the available options when reordering an instruction. As the EOT flag is an implied write to the render target in the FS, it can be considered a side effect. This patch shouldn't actually have any impact on the current code since the EOT flag implies that the opcode is already one with side effects, FS_OPCODE_FB_WRITE. The next patch however will introduce an optimization whereby the EOT flag can occur with an opcode SHADER_OPCODE_TEX, and as that instruction will perform the same implied write to the render target, it cannot be reordered. v2: Remove extra whitespace (Matt) Signed-off-by: Ben Widawsky Reviewed-by: Kenneth Graunke Reviewed-by: Matt Turner --- src/mesa/drivers/dri/i965/brw_fs.cpp | 6 ++++++ src/mesa/drivers/dri/i965/brw_ir_fs.h | 1 + 2 files changed, 7 insertions(+) diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp index 8bd8da2389d..aea1ebb7dea 100644 --- a/src/mesa/drivers/dri/i965/brw_fs.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp @@ -531,6 +531,12 @@ fs_inst::can_do_source_mods(struct brw_context *brw) return true; } +bool +fs_inst::has_side_effects() const +{ + return this->eot || backend_instruction::has_side_effects(); +} + void fs_reg::init() { diff --git a/src/mesa/drivers/dri/i965/brw_ir_fs.h b/src/mesa/drivers/dri/i965/brw_ir_fs.h index 9ef1261ab3b..30c19f41a31 100644 --- a/src/mesa/drivers/dri/i965/brw_ir_fs.h +++ b/src/mesa/drivers/dri/i965/brw_ir_fs.h @@ -225,6 +225,7 @@ public: bool is_partial_write() const; int regs_read(int arg) const; bool can_do_source_mods(struct brw_context *brw); + bool has_side_effects() const; bool reads_flag() const; bool writes_flag() const; -- 2.30.2