| /* |
| * Copyright © 2016 Intel Corporation |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a |
| * copy of this software and associated documentation files (the "Software"), |
| * to deal in the Software without restriction, including without limitation |
| * the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| * and/or sell copies of the Software, and to permit persons to whom the |
| * Software is furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice (including the next |
| * paragraph) shall be included in all copies or substantial portions of the |
| * Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
| * IN THE SOFTWARE. |
| */ |
| |
| #include "nir.h" |
| #include "nir_builder.h" |
| #include "nir_deref.h" |
| |
| static void |
| emit_load_store_deref(nir_builder *b, nir_intrinsic_instr *orig_instr, |
| nir_deref_instr *parent, |
| nir_deref_instr **deref_arr, |
| nir_ssa_def **dest, nir_ssa_def *src); |
| |
| static void |
| emit_indirect_load_store_deref(nir_builder *b, nir_intrinsic_instr *orig_instr, |
| nir_deref_instr *parent, |
| nir_deref_instr **deref_arr, |
| int start, int end, |
| nir_ssa_def **dest, nir_ssa_def *src) |
| { |
| assert(start < end); |
| if (start == end - 1) { |
| emit_load_store_deref(b, orig_instr, |
| nir_build_deref_array_imm(b, parent, start), |
| deref_arr + 1, dest, src); |
| } else { |
| int mid = start + (end - start) / 2; |
| |
| nir_ssa_def *then_dest, *else_dest; |
| |
| nir_deref_instr *deref = *deref_arr; |
| assert(deref->deref_type == nir_deref_type_array); |
| |
| nir_push_if(b, nir_ilt(b, deref->arr.index.ssa, nir_imm_intN_t(b, mid, parent->dest.ssa.bit_size))); |
| emit_indirect_load_store_deref(b, orig_instr, parent, deref_arr, |
| start, mid, &then_dest, src); |
| nir_push_else(b, NULL); |
| emit_indirect_load_store_deref(b, orig_instr, parent, deref_arr, |
| mid, end, &else_dest, src); |
| nir_pop_if(b, NULL); |
| |
| if (src == NULL) |
| *dest = nir_if_phi(b, then_dest, else_dest); |
| } |
| } |
| |
| static void |
| emit_load_store_deref(nir_builder *b, nir_intrinsic_instr *orig_instr, |
| nir_deref_instr *parent, |
| nir_deref_instr **deref_arr, |
| nir_ssa_def **dest, nir_ssa_def *src) |
| { |
| for (; *deref_arr; deref_arr++) { |
| nir_deref_instr *deref = *deref_arr; |
| if (deref->deref_type == nir_deref_type_array && |
| !nir_src_is_const(deref->arr.index)) { |
| int length = glsl_get_length(parent->type); |
| |
| emit_indirect_load_store_deref(b, orig_instr, parent, deref_arr, |
| 0, length, dest, src); |
| return; |
| } |
| |
| parent = nir_build_deref_follower(b, parent, deref); |
| } |
| |
| /* We reached the end of the deref chain. Emit the instruction */ |
| assert(*deref_arr == NULL); |
| |
| if (src == NULL) { |
| /* This is a load instruction */ |
| nir_intrinsic_instr *load = |
| nir_intrinsic_instr_create(b->shader, orig_instr->intrinsic); |
| load->num_components = orig_instr->num_components; |
| |
| load->src[0] = nir_src_for_ssa(&parent->dest.ssa); |
| |
| /* Copy over any other sources. This is needed for interp_deref_at */ |
| for (unsigned i = 1; |
| i < nir_intrinsic_infos[orig_instr->intrinsic].num_srcs; i++) |
| nir_src_copy(&load->src[i], &orig_instr->src[i], load); |
| |
| nir_ssa_dest_init(&load->instr, &load->dest, |
| orig_instr->dest.ssa.num_components, |
| orig_instr->dest.ssa.bit_size, NULL); |
| nir_builder_instr_insert(b, &load->instr); |
| *dest = &load->dest.ssa; |
| } else { |
| assert(orig_instr->intrinsic == nir_intrinsic_store_deref); |
| nir_store_deref(b, parent, src, nir_intrinsic_write_mask(orig_instr)); |
| } |
| } |
| |
| static bool |
| lower_indirect_derefs_block(nir_block *block, nir_builder *b, |
| nir_variable_mode modes, |
| uint32_t max_lower_array_len) |
| { |
| bool progress = false; |
| |
| nir_foreach_instr_safe(instr, block) { |
| if (instr->type != nir_instr_type_intrinsic) |
| continue; |
| |
| nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); |
| if (intrin->intrinsic != nir_intrinsic_load_deref && |
| intrin->intrinsic != nir_intrinsic_interp_deref_at_centroid && |
| intrin->intrinsic != nir_intrinsic_interp_deref_at_sample && |
| intrin->intrinsic != nir_intrinsic_interp_deref_at_offset && |
| intrin->intrinsic != nir_intrinsic_interp_deref_at_vertex && |
| intrin->intrinsic != nir_intrinsic_store_deref) |
| continue; |
| |
| nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]); |
| |
| /* Walk the deref chain back to the base and look for indirects */ |
| uint32_t indirect_array_len = 1; |
| bool has_indirect = false; |
| nir_deref_instr *base = deref; |
| while (base && base->deref_type != nir_deref_type_var) { |
| nir_deref_instr *parent = nir_deref_instr_parent(base); |
| if (base->deref_type == nir_deref_type_array && |
| !nir_src_is_const(base->arr.index)) { |
| indirect_array_len *= glsl_get_length(parent->type); |
| has_indirect = true; |
| } |
| |
| base = parent; |
| } |
| |
| if (!has_indirect || !base || indirect_array_len > max_lower_array_len) |
| continue; |
| |
| /* Only lower variables whose mode is in the mask, or compact |
| * array variables. (We can't handle indirects on tightly packed |
| * scalar arrays, so we need to lower them regardless.) |
| */ |
| if (!(modes & base->var->data.mode) && !base->var->data.compact) |
| continue; |
| |
| b->cursor = nir_instr_remove(&intrin->instr); |
| |
| nir_deref_path path; |
| nir_deref_path_init(&path, deref, NULL); |
| assert(path.path[0] == base); |
| |
| if (intrin->intrinsic == nir_intrinsic_store_deref) { |
| assert(intrin->src[1].is_ssa); |
| emit_load_store_deref(b, intrin, base, &path.path[1], |
| NULL, intrin->src[1].ssa); |
| } else { |
| nir_ssa_def *result; |
| emit_load_store_deref(b, intrin, base, &path.path[1], |
| &result, NULL); |
| nir_ssa_def_rewrite_uses(&intrin->dest.ssa, nir_src_for_ssa(result)); |
| } |
| |
| nir_deref_path_finish(&path); |
| |
| progress = true; |
| } |
| |
| return progress; |
| } |
| |
| static bool |
| lower_indirects_impl(nir_function_impl *impl, nir_variable_mode modes, |
| uint32_t max_lower_array_len) |
| { |
| nir_builder builder; |
| nir_builder_init(&builder, impl); |
| bool progress = false; |
| |
| nir_foreach_block_safe(block, impl) { |
| progress |= lower_indirect_derefs_block(block, &builder, modes, |
| max_lower_array_len); |
| } |
| |
| if (progress) |
| nir_metadata_preserve(impl, nir_metadata_none); |
| else |
| nir_metadata_preserve(impl, nir_metadata_all); |
| |
| return progress; |
| } |
| |
| /** Lowers indirect variable loads/stores to direct loads/stores. |
| * |
| * The pass works by replacing any indirect load or store with an if-ladder |
| * that does a binary search on the array index. |
| */ |
| bool |
| nir_lower_indirect_derefs(nir_shader *shader, nir_variable_mode modes, |
| uint32_t max_lower_array_len) |
| { |
| bool progress = false; |
| |
| nir_foreach_function(function, shader) { |
| if (function->impl) { |
| progress = lower_indirects_impl(function->impl, modes, |
| max_lower_array_len) || progress; |
| } |
| } |
| |
| return progress; |
| } |
