diff options
| -rw-r--r-- | src/glsl/nir/nir_lower_vec_to_movs.c | 49 |
1 files changed, 36 insertions, 13 deletions
diff --git a/src/glsl/nir/nir_lower_vec_to_movs.c b/src/glsl/nir/nir_lower_vec_to_movs.c index 9ff86ea7543..2cb0457f9ba 100644 --- a/src/glsl/nir/nir_lower_vec_to_movs.c +++ b/src/glsl/nir/nir_lower_vec_to_movs.c @@ -79,6 +79,14 @@ insert_mov(nir_alu_instr *vec, unsigned start_idx, nir_shader *shader) return mov->dest.write_mask; } +static bool +has_replicated_dest(nir_alu_instr *alu) +{ + return alu->op == nir_op_fdot_replicated2 || + alu->op == nir_op_fdot_replicated3 || + alu->op == nir_op_fdot_replicated4; +} + /* Attempts to coalesce the "move" from the given source of the vec to the * destination of the instruction generating the value. If, for whatever * reason, we cannot coalesce the mmove, it does nothing and returns 0. We @@ -116,19 +124,28 @@ try_coalesce(nir_alu_instr *vec, unsigned start_idx, nir_shader *shader) nir_alu_instr *src_alu = nir_instr_as_alu(vec->src[start_idx].src.ssa->parent_instr); - /* We only care about being able to re-swizzle the instruction if it is - * something that we can reswizzle. It must be per-component. - */ - if (nir_op_infos[src_alu->op].output_size != 0) - return 0; - - /* If we are going to reswizzle the instruction, we can't have any - * non-per-component sources either. - */ - for (unsigned j = 0; j < nir_op_infos[src_alu->op].num_inputs; j++) - if (nir_op_infos[src_alu->op].input_sizes[j] != 0) + if (has_replicated_dest(src_alu)) { + /* The fdot instruction is special: It replicates its result to all + * components. This means that we can always rewrite its destination + * and we don't need to swizzle anything. + */ + } else { + /* We only care about being able to re-swizzle the instruction if it is + * something that we can reswizzle. It must be per-component. The one + * exception to this is the fdotN instructions which implicitly splat + * their result out to all channels. + */ + if (nir_op_infos[src_alu->op].output_size != 0) return 0; + /* If we are going to reswizzle the instruction, we can't have any + * non-per-component sources either. + */ + for (unsigned j = 0; j < nir_op_infos[src_alu->op].num_inputs; j++) + if (nir_op_infos[src_alu->op].input_sizes[j] != 0) + return 0; + } + /* Stash off all of the ALU instruction's swizzles. */ uint8_t swizzles[4][4]; for (unsigned j = 0; j < nir_op_infos[src_alu->op].num_inputs; j++) @@ -148,8 +165,14 @@ try_coalesce(nir_alu_instr *vec, unsigned start_idx, nir_shader *shader) * instruction so we can re-swizzle that component to match. */ write_mask |= 1 << i; - for (unsigned j = 0; j < nir_op_infos[src_alu->op].num_inputs; j++) - src_alu->src[j].swizzle[i] = swizzles[j][vec->src[i].swizzle[0]]; + if (has_replicated_dest(src_alu)) { + /* Since the destination is a single replicated value, we don't need + * to do any reswizzling + */ + } else { + for (unsigned j = 0; j < nir_op_infos[src_alu->op].num_inputs; j++) + src_alu->src[j].swizzle[i] = swizzles[j][vec->src[i].swizzle[0]]; + } /* Clear the no longer needed vec source */ nir_instr_rewrite_src(&vec->instr, &vec->src[i].src, NIR_SRC_INIT); |