Module: Mesa Branch: master Commit: c638ea3d19d46cfe65739af2c78373146ed50737 URL: http://cgit.freedesktop.org/mesa/mesa/commit/?id=c638ea3d19d46cfe65739af2c78373146ed50737
Author: Matt Turner <[email protected]> Date: Wed Apr 9 13:38:14 2014 -0700 i965: Don't make instructions with a null dest a barrier to scheduling. Now that we properly track accumulator dependencies, the scheduler is able to schedule instructions between the mach and mov in the common the integer multiplication pattern: mul acc0, x, y mach null, x, y mov dest, acc0 Since a null destination implies no dependency on the destination, we can also safely schedule instructions (that don't write the accumulator) between the mul and mach. GAINED: 103 LOST: 43 Causes one program to spill (643 -> 1076 instructions). I committed this patch last year (commit 42a26cb5) but reverted it (commit 0d3f83f4) after inexplicable artifacts in Kerbal Space Program (bug 78648). Tapani reapplied this patch and could not reproduce the bug with current Mesa. Reviewed-by: Kenneth Graunke <[email protected]> Reviewed-by: Jason Ekstrand <[email protected]> --- src/mesa/drivers/dri/i965/brw_schedule_instructions.cpp | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_schedule_instructions.cpp b/src/mesa/drivers/dri/i965/brw_schedule_instructions.cpp index b552cf8..40b5715 100644 --- a/src/mesa/drivers/dri/i965/brw_schedule_instructions.cpp +++ b/src/mesa/drivers/dri/i965/brw_schedule_instructions.cpp @@ -879,7 +879,8 @@ fs_instruction_scheduler::calculate_deps() } else if (inst->dst.is_accumulator()) { add_dep(last_accumulator_write, n); last_accumulator_write = n; - } else if (inst->dst.file != BAD_FILE) { + } else if (inst->dst.file != BAD_FILE && + !inst->dst.is_null()) { add_barrier_deps(n); } @@ -1005,7 +1006,8 @@ fs_instruction_scheduler::calculate_deps() } } else if (inst->dst.is_accumulator()) { last_accumulator_write = n; - } else if (inst->dst.file != BAD_FILE) { + } else if (inst->dst.file != BAD_FILE && + !inst->dst.is_null()) { add_barrier_deps(n); } @@ -1112,7 +1114,8 @@ vec4_instruction_scheduler::calculate_deps() } else if (inst->dst.is_accumulator()) { add_dep(last_accumulator_write, n); last_accumulator_write = n; - } else if (inst->dst.file != BAD_FILE) { + } else if (inst->dst.file != BAD_FILE && + !inst->dst.is_null()) { add_barrier_deps(n); } @@ -1199,7 +1202,8 @@ vec4_instruction_scheduler::calculate_deps() last_fixed_grf_write = n; } else if (inst->dst.is_accumulator()) { last_accumulator_write = n; - } else if (inst->dst.file != BAD_FILE) { + } else if (inst->dst.file != BAD_FILE && + !inst->dst.is_null()) { add_barrier_deps(n); } _______________________________________________ mesa-commit mailing list [email protected] http://lists.freedesktop.org/mailman/listinfo/mesa-commit
