diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/compiler/nir/nir_opt_intrinsics.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/src/compiler/nir/nir_opt_intrinsics.c b/src/compiler/nir/nir_opt_intrinsics.c index 26a0f9650ad..d5fdc516007 100644 --- a/src/compiler/nir/nir_opt_intrinsics.c +++ b/src/compiler/nir/nir_opt_intrinsics.c @@ -28,6 +28,26 @@ * \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) { @@ -95,10 +115,10 @@ opt_intrinsics_impl(nir_function_impl *impl) replacement = nir_ishl(&b, nir_imm_int64(&b, 1ull), count); break; case nir_intrinsic_load_subgroup_ge_mask: - replacement = nir_ishl(&b, nir_imm_int64(&b, ~0ull), count); + replacement = high_subgroup_mask(&b, count, ~0ull); break; case nir_intrinsic_load_subgroup_gt_mask: - replacement = nir_ishl(&b, nir_imm_int64(&b, ~1ull), count); + 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)); |