From 9701008d64171b1f16be9a8a69555df2b651c37b Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Tue, 24 Mar 2020 09:10:06 -0700 Subject: [PATCH] freedreno/ir3/sched: awareness of partial liveness Realize that certain instructions make a vecN live, and account for this, in hopes of scheduling the remaining components of the vecN sooner. Signed-off-by: Rob Clark Part-of: --- src/freedreno/ir3/ir3_sched.c | 45 ++++++++++++++++++++++++++++++++++- 1 file changed, 44 insertions(+), 1 deletion(-) diff --git a/src/freedreno/ir3/ir3_sched.c b/src/freedreno/ir3/ir3_sched.c index 95c89ae8461..46448c10b4b 100644 --- a/src/freedreno/ir3/ir3_sched.c +++ b/src/freedreno/ir3/ir3_sched.c @@ -104,6 +104,22 @@ struct ir3_sched_node { unsigned delay; unsigned max_delay; + /* For instructions that are a meta:collect src, once we schedule + * the first src of the collect, the entire vecN is live (at least + * from the PoV of the first RA pass.. the 2nd scalar pass can fill + * in some of the gaps, but often not all). So we want to help out + * RA, and realize that as soon as we schedule the first collect + * src, there is no penalty to schedule the remainder (ie. they + * don't make additional values live). In fact we'd prefer to + * schedule the rest ASAP to minimize the live range of the vecN. + * + * For instructions that are the src of a collect, we track the + * corresponding collect, and mark them as partially live as soon + * as any one of the src's is scheduled. + */ + struct ir3_instruction *collect; + bool partially_live; + /* Is this instruction a direct or indirect dependency for a kill? * If so, we should prioritize it when possible */ @@ -158,6 +174,19 @@ schedule(struct ir3_sched_ctx *ctx, struct ir3_instruction *instr) struct ir3_sched_node *n = instr->data; + /* If this instruction is a meta:collect src, mark the remaining + * collect srcs as partially live. + */ + if (n->collect) { + struct ir3_instruction *src; + foreach_ssa_src (src, n->collect) { + if (src->block != instr->block) + continue; + struct ir3_sched_node *sn = src->data; + sn->partially_live = true; + } + } + dag_prune_head(ctx->dag, &n->dag); } @@ -340,10 +369,17 @@ use_count(struct ir3_instruction *instr) static int live_effect(struct ir3_instruction *instr) { + struct ir3_sched_node *n = instr->data; struct ir3_instruction *src; - int new_live = dest_regs(instr); + int new_live = n->partially_live ? 0 : dest_regs(instr); int freed_live = 0; + /* if we schedule something that causes a vecN to be live, + * then count all it's other components too: + */ + if (n->collect) + new_live *= n->collect->regs_count - 1; + foreach_ssa_src_n (src, n, instr) { if (__is_false_dep(instr, n)) continue; @@ -697,6 +733,13 @@ sched_node_add_dep(struct ir3_instruction *instr, struct ir3_instruction *src, i struct ir3_sched_node *n = instr->data; struct ir3_sched_node *sn = src->data; + /* If src is consumed by a collect, track that to realize that once + * any of the collect srcs are live, we should hurry up and schedule + * the rest. + */ + if (instr->opc == OPC_META_COLLECT) + sn->collect = instr; + dag_add_edge(&sn->dag, &n->dag, NULL); unsigned d = ir3_delayslots(src, instr, i, true); -- 2.30.2