From 85fce2d2f50335b1d204dbaedc36cdd37164a9c0 Mon Sep 17 00:00:00 2001 From: Connor Abbott Date: Sun, 7 Jun 2015 00:37:27 -0400 Subject: [PATCH] i965/sched: write-after-read dependencies are free Although write-after-write dependencies have the same latency as read-after-write dependencies due to how the register scoreboard works, write-after-read dependencies aren't checked by the EU at all, so they're purely a constraint on how the scheduler can order the instructions. v2: fix accumulator dependencies too. Reviewed-by: Jason Ekstrand --- .../drivers/dri/i965/brw_schedule_instructions.cpp | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_schedule_instructions.cpp b/src/mesa/drivers/dri/i965/brw_schedule_instructions.cpp index 3e86cb05cce..094c47aba37 100644 --- a/src/mesa/drivers/dri/i965/brw_schedule_instructions.cpp +++ b/src/mesa/drivers/dri/i965/brw_schedule_instructions.cpp @@ -927,10 +927,10 @@ fs_instruction_scheduler::calculate_deps() if (inst->src[i].file == GRF) { if (post_reg_alloc) { for (int r = 0; r < inst->regs_read(i); r++) - add_dep(n, last_grf_write[inst->src[i].reg + r]); + add_dep(n, last_grf_write[inst->src[i].reg + r], 0); } else { for (int r = 0; r < inst->regs_read(i); r++) { - add_dep(n, last_grf_write[inst->src[i].reg * 16 + inst->src[i].reg_offset + r]); + add_dep(n, last_grf_write[inst->src[i].reg * 16 + inst->src[i].reg_offset + r], 0); } } } else if (inst->src[i].file == HW_REG && @@ -941,12 +941,12 @@ fs_instruction_scheduler::calculate_deps() if (inst->src[i].fixed_hw_reg.vstride == BRW_VERTICAL_STRIDE_0) size = 1; for (int r = 0; r < size; r++) - add_dep(n, last_grf_write[inst->src[i].fixed_hw_reg.nr + r]); + add_dep(n, last_grf_write[inst->src[i].fixed_hw_reg.nr + r], 0); } else { - add_dep(n, last_fixed_grf_write); + add_dep(n, last_fixed_grf_write, 0); } } else if (inst->src[i].is_accumulator()) { - add_dep(n, last_accumulator_write); + add_dep(n, last_accumulator_write, 0); } else if (inst->src[i].file != BAD_FILE && inst->src[i].file != IMM && inst->src[i].file != UNIFORM && -- 2.30.2