From e665e65f969186101112d154eb1a43d945814080 Mon Sep 17 00:00:00 2001 From: Rob Clark Date: Fri, 18 Oct 2019 15:46:59 -0700 Subject: [PATCH] freedreno/ir3: allow copy-propagate out of fanout Now that we fixed the sharp edges that this was papering over, we can relax the restriction about eliminating a mov coming out of a fanout (for example from result of texture fetch). Signed-off-by: Rob Clark Reviewed-by: Kristian H. Kristensen --- src/freedreno/ir3/ir3_cp.c | 34 +++++++++++++++++++++++++++------- 1 file changed, 27 insertions(+), 7 deletions(-) diff --git a/src/freedreno/ir3/ir3_cp.c b/src/freedreno/ir3/ir3_cp.c index a79560ec579..01386b434ee 100644 --- a/src/freedreno/ir3/ir3_cp.c +++ b/src/freedreno/ir3/ir3_cp.c @@ -44,8 +44,16 @@ struct ir3_cp_ctx { struct ir3_shader_variant *so; }; -/* is it a type preserving mov, with ok flags? */ -static bool is_eligible_mov(struct ir3_instruction *instr, bool allow_flags) +/* is it a type preserving mov, with ok flags? + * + * @instr: the mov to consider removing + * @dst_instr: the instruction consuming the mov (instr) + * + * TODO maybe drop allow_flags since this is only false when dst is + * NULL (ie. outputs) + */ +static bool is_eligible_mov(struct ir3_instruction *instr, + struct ir3_instruction *dst_instr, bool allow_flags) { if (is_same_type_mov(instr)) { struct ir3_register *dst = instr->regs[0]; @@ -70,9 +78,21 @@ static bool is_eligible_mov(struct ir3_instruction *instr, bool allow_flags) IR3_REG_SABS | IR3_REG_SNEG | IR3_REG_BNOT)) return false; - /* TODO: remove this hack: */ - if (src_instr->opc == OPC_META_FO) - return false; + /* If src is coming from fanout/split (ie. one component of a + * texture fetch, etc) and we have constraints on swizzle of + * destination, then skip it. + * + * We could possibly do a bit better, and copy-propagation if + * we can CP all components that are being fanned out. + */ + if (src_instr->opc == OPC_META_FO) { + if (!dst_instr) + return false; + if (dst_instr->opc == OPC_META_FI) + return false; + if (dst_instr->cp.left || dst_instr->cp.right) + return false; + } return true; } @@ -427,7 +447,7 @@ reg_cp(struct ir3_cp_ctx *ctx, struct ir3_instruction *instr, { struct ir3_instruction *src = ssa(reg); - if (is_eligible_mov(src, true)) { + if (is_eligible_mov(src, instr, true)) { /* simple case, no immed/const/relativ, only mov's w/ ssa src: */ struct ir3_register *src_reg = src->regs[1]; unsigned new_flags = reg->flags; @@ -584,7 +604,7 @@ reg_cp(struct ir3_cp_ctx *ctx, struct ir3_instruction *instr, static struct ir3_instruction * eliminate_output_mov(struct ir3_instruction *instr) { - if (is_eligible_mov(instr, false)) { + if (is_eligible_mov(instr, NULL, false)) { struct ir3_register *reg = instr->regs[1]; if (!(reg->flags & IR3_REG_ARRAY)) { struct ir3_instruction *src_instr = ssa(reg); -- 2.30.2