From 28da82f9783091cb3e79586962f98a5bc165cff8 Mon Sep 17 00:00:00 2001 From: Jason Ekstrand Date: Tue, 22 Aug 2017 13:23:59 -0700 Subject: nir: Add a new subgroups lowering pass This commit pulls nir_lower_read_invocations_to_scalar along with most of the guts of nir_opt_intrinsics (which mostly does subgroup lowering) into a new nir_lower_subgroups pass. There are various other bits of subgroup lowering that we're going to want to do so it makes a bit more sense to keep it all together in one pass. We also move it in i965 to happen after nir_lower_system_values to ensure that because we want to handle the subgroup mask system value intrinsics here. Reviewed-by: Iago Toral Quiroga --- src/compiler/nir/nir_opt_intrinsics.c | 71 +++-------------------------------- 1 file changed, 6 insertions(+), 65 deletions(-) (limited to 'src/compiler/nir/nir_opt_intrinsics.c') diff --git a/src/compiler/nir/nir_opt_intrinsics.c b/src/compiler/nir/nir_opt_intrinsics.c index d5fdc516007..98c8b1a01e8 100644 --- a/src/compiler/nir/nir_opt_intrinsics.c +++ b/src/compiler/nir/nir_opt_intrinsics.c @@ -28,26 +28,6 @@ * \file nir_opt_intrinsics.c */ -static nir_ssa_def * -high_subgroup_mask(nir_builder *b, - nir_ssa_def *count, - uint64_t base_mask) -{ - /* group_mask could probably be calculated more efficiently but we want to - * be sure not to shift by 64 if the subgroup size is 64 because the GLSL - * shift operator is undefined in that case. In any case if we were worried - * about efficency this should probably be done further down because the - * subgroup size is likely to be known at compile time. - */ - nir_ssa_def *subgroup_size = nir_load_subgroup_size(b); - nir_ssa_def *all_bits = nir_imm_int64(b, ~0ull); - nir_ssa_def *shift = nir_isub(b, nir_imm_int(b, 64), subgroup_size); - nir_ssa_def *group_mask = nir_ushr(b, all_bits, shift); - nir_ssa_def *higher_bits = nir_ishl(b, nir_imm_int64(b, base_mask), count); - - return nir_iand(b, higher_bits, group_mask); -} - static bool opt_intrinsics_impl(nir_function_impl *impl) { @@ -66,22 +46,14 @@ opt_intrinsics_impl(nir_function_impl *impl) switch (intrin->intrinsic) { case nir_intrinsic_vote_any: - case nir_intrinsic_vote_all: { - nir_const_value *val = nir_src_as_const_value(intrin->src[0]); - if (!val && !b.shader->options->lower_vote_trivial) - continue; - - replacement = nir_ssa_for_src(&b, intrin->src[0], 1); + case nir_intrinsic_vote_all: + if (nir_src_as_const_value(intrin->src[0])) + replacement = nir_ssa_for_src(&b, intrin->src[0], 1); break; - } - case nir_intrinsic_vote_eq: { - nir_const_value *val = nir_src_as_const_value(intrin->src[0]); - if (!val && !b.shader->options->lower_vote_trivial) - continue; - - replacement = nir_imm_int(&b, NIR_TRUE); + case nir_intrinsic_vote_eq: + if (nir_src_as_const_value(intrin->src[0])) + replacement = nir_imm_int(&b, NIR_TRUE); break; - } case nir_intrinsic_ballot: { assert(b.shader->options->max_subgroup_size != 0); if (b.shader->options->max_subgroup_size > 32 || @@ -100,37 +72,6 @@ opt_intrinsics_impl(nir_function_impl *impl) nir_imm_int(&b, 0)); break; } - case nir_intrinsic_load_subgroup_eq_mask: - case nir_intrinsic_load_subgroup_ge_mask: - case nir_intrinsic_load_subgroup_gt_mask: - case nir_intrinsic_load_subgroup_le_mask: - case nir_intrinsic_load_subgroup_lt_mask: { - if (!b.shader->options->lower_subgroup_masks) - break; - - nir_ssa_def *count = nir_load_subgroup_invocation(&b); - - switch (intrin->intrinsic) { - case nir_intrinsic_load_subgroup_eq_mask: - replacement = nir_ishl(&b, nir_imm_int64(&b, 1ull), count); - break; - case nir_intrinsic_load_subgroup_ge_mask: - replacement = high_subgroup_mask(&b, count, ~0ull); - break; - case nir_intrinsic_load_subgroup_gt_mask: - replacement = high_subgroup_mask(&b, count, ~1ull); - break; - case nir_intrinsic_load_subgroup_le_mask: - replacement = nir_inot(&b, nir_ishl(&b, nir_imm_int64(&b, ~1ull), count)); - break; - case nir_intrinsic_load_subgroup_lt_mask: - replacement = nir_inot(&b, nir_ishl(&b, nir_imm_int64(&b, ~0ull), count)); - break; - default: - unreachable("you seriously can't tell this is unreachable?"); - } - break; - } default: break; } -- cgit v1.2.3