From ed5f0245156006341ef8cf39376572ffad246a23 Mon Sep 17 00:00:00 2001 From: Ian Romanick Date: Tue, 7 May 2019 10:27:11 -0700 Subject: [PATCH] =?utf8?q?nir/flrp:=20Reassociate=20add=20in=20flrp(=C2=B1?= =?utf8?q?1,=20b,=20c)=20lowering=20path?= MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit With this reassociation, this lowering path is still beneficial. Ice Lake total instructions in shared programs: 17220191 -> 17207181 (-0.08%) instructions in affected programs: 999871 -> 986861 (-1.30%) helped: 3703 HURT: 17 helped stats (abs) min: 1 max: 686 x̄: 3.52 x̃: 3 helped stats (rel) min: 0.09% max: 51.97% x̄: 2.21% x̃: 1.35% HURT stats (abs) min: 1 max: 9 x̄: 1.47 x̃: 1 HURT stats (rel) min: 0.08% max: 4.55% x̄: 0.78% x̃: 0.55% 95% mean confidence interval for instructions value: -4.01 -2.99 95% mean confidence interval for instructions %-change: -2.29% -2.11% Instructions are helped. total cycles in shared programs: 360871298 -> 360755040 (-0.03%) cycles in affected programs: 9931334 -> 9815076 (-1.17%) helped: 2388 HURT: 1569 helped stats (abs) min: 1 max: 10228 x̄: 93.54 x̃: 18 helped stats (rel) min: <.01% max: 74.11% x̄: 3.36% x̃: 1.07% HURT stats (abs) min: 1 max: 1917 x̄: 68.27 x̃: 22 HURT stats (rel) min: <.01% max: 44.90% x̄: 3.44% x̃: 1.72% 95% mean confidence interval for cycles value: -39.48 -19.28 95% mean confidence interval for cycles %-change: -0.86% -0.46% Cycles are helped. total spills in shared programs: 12355 -> 12159 (-1.59%) spills in affected programs: 295 -> 99 (-66.44%) helped: 2 HURT: 1 total fills in shared programs: 25398 -> 25207 (-0.75%) fills in affected programs: 288 -> 97 (-66.32%) helped: 2 HURT: 1 LOST: 3 GAINED: 44 Iron Lake total instructions in shared programs: 8169225 -> 8159729 (-0.12%) instructions in affected programs: 1025712 -> 1016216 (-0.93%) helped: 3352 HURT: 0 helped stats (abs) min: 1 max: 6 x̄: 2.83 x̃: 3 helped stats (rel) min: 0.15% max: 12.00% x̄: 1.51% x̃: 1.05% 95% mean confidence interval for instructions value: -2.86 -2.80 95% mean confidence interval for instructions %-change: -1.56% -1.46% Instructions are helped. total cycles in shared programs: 188656796 -> 188612280 (-0.02%) cycles in affected programs: 18633584 -> 18589068 (-0.24%) helped: 3085 HURT: 14 helped stats (abs) min: 2 max: 72 x̄: 14.45 x̃: 12 helped stats (rel) min: 0.02% max: 5.73% x̄: 0.73% x̃: 0.31% HURT stats (abs) min: 2 max: 4 x̄: 3.71 x̃: 4 HURT stats (rel) min: <.01% max: <.01% x̄: <.01% x̃: <.01% 95% mean confidence interval for cycles value: -14.55 -14.18 95% mean confidence interval for cycles %-change: -0.76% -0.69% Cycles are helped. GM45 total instructions in shared programs: 5026905 -> 5021856 (-0.10%) instructions in affected programs: 584169 -> 579120 (-0.86%) helped: 1776 HURT: 0 helped stats (abs) min: 1 max: 6 x̄: 2.84 x̃: 3 helped stats (rel) min: 0.15% max: 11.11% x̄: 1.43% x̃: 0.98% 95% mean confidence interval for instructions value: -2.88 -2.80 95% mean confidence interval for instructions %-change: -1.50% -1.37% Instructions are helped. total cycles in shared programs: 129047376 -> 129018918 (-0.02%) cycles in affected programs: 12941924 -> 12913466 (-0.22%) helped: 1722 HURT: 14 helped stats (abs) min: 4 max: 72 x̄: 16.56 x̃: 18 helped stats (rel) min: 0.02% max: 5.73% x̄: 0.72% x̃: 0.30% HURT stats (abs) min: 2 max: 4 x̄: 3.71 x̃: 4 HURT stats (rel) min: <.01% max: <.01% x̄: <.01% x̃: <.01% 95% mean confidence interval for cycles value: -16.65 -16.13 95% mean confidence interval for cycles %-change: -0.76% -0.66% Cycles are helped. Reviewed-by: Matt Turner Reviewed-by: Samuel Pitoiset --- src/compiler/nir/nir_lower_flrp.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/src/compiler/nir/nir_lower_flrp.c b/src/compiler/nir/nir_lower_flrp.c index 41342403d48..bc5d71db1b0 100644 --- a/src/compiler/nir/nir_lower_flrp.c +++ b/src/compiler/nir/nir_lower_flrp.c @@ -171,7 +171,7 @@ replace_with_fast(struct nir_builder *bld, struct u_vector *dead_flrp, } /** - * Replace flrp(a, b, c) with (b*c ± c) + a + * Replace flrp(a, b, c) with (b*c ± c) + a => b*c + (a ± c) * * \note: This only works if a = ±1. */ @@ -193,14 +193,14 @@ replace_with_expanded_ffma_and_add(struct nir_builder *bld, nir_ssa_def *const neg_c = nir_fneg(bld, c); nir_instr_as_alu(neg_c->parent_instr)->exact = alu->exact; - inner_sum = nir_fadd(bld, b_times_c, neg_c); + inner_sum = nir_fadd(bld, a, neg_c); } else { - inner_sum = nir_fadd(bld, b_times_c, c); + inner_sum = nir_fadd(bld, a, c); } nir_instr_as_alu(inner_sum->parent_instr)->exact = alu->exact; - nir_ssa_def *const outer_sum = nir_fadd(bld, inner_sum, a); + nir_ssa_def *const outer_sum = nir_fadd(bld, inner_sum, b_times_c); nir_instr_as_alu(outer_sum->parent_instr)->exact = alu->exact; nir_ssa_def_rewrite_uses(&alu->dest.dest.ssa, nir_src_for_ssa(outer_sum)); -- 2.30.2