/* * Copyright © 2017 Timothy Arceri * * 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" /** @file nir_lower_io_arrays_to_elements.c * * Split arrays/matrices with direct indexing into individual elements. This * will allow optimisation passes to better clean up unused elements. * */ static unsigned get_io_offset(nir_builder *b, nir_deref_instr *deref, nir_variable *var, unsigned *element_index, unsigned *xfb_offset, nir_ssa_def **vertex_index) { nir_deref_path path; nir_deref_path_init(&path, deref, NULL); assert(path.path[0]->deref_type == nir_deref_type_var); nir_deref_instr **p = &path.path[1]; /* For per-vertex input arrays (i.e. geometry shader inputs), skip the * outermost array index. Process the rest normally. */ if (nir_is_per_vertex_io(var, b->shader->info.stage)) { *vertex_index = nir_ssa_for_src(b, (*p)->arr.index, 1); p++; } unsigned offset = 0; *xfb_offset = 0; for (; *p; p++) { if ((*p)->deref_type == nir_deref_type_array) { /* must not be indirect dereference */ unsigned index = nir_src_as_uint((*p)->arr.index); unsigned size = glsl_count_attribute_slots((*p)->type, false); offset += size * index; xfb_offset += index * glsl_get_component_slots((*p)->type) * 4; unsigned num_elements = glsl_type_is_array((*p)->type) ? glsl_get_aoa_size((*p)->type) : 1; num_elements *= glsl_type_is_matrix(glsl_without_array((*p)->type)) ? glsl_get_matrix_columns(glsl_without_array((*p)->type)) : 1; *element_index += num_elements * index; } else if ((*p)->deref_type == nir_deref_type_struct) { /* TODO: we could also add struct splitting support to this pass */ break; } } nir_deref_path_finish(&path); return offset; } static nir_variable ** get_array_elements(struct hash_table *ht, nir_variable *var, gl_shader_stage stage) { nir_variable **elements; struct hash_entry *entry = _mesa_hash_table_search(ht, var); if (!entry) { const struct glsl_type *type = var->type; if (nir_is_per_vertex_io(var, stage)) { assert(glsl_type_is_array(type)); type = glsl_get_array_element(type); } unsigned num_elements = glsl_type_is_array(type) ? glsl_get_aoa_size(type) : 1; num_elements *= glsl_type_is_matrix(glsl_without_array(type)) ? glsl_get_matrix_columns(glsl_without_array(type)) : 1; elements = (nir_variable **) calloc(num_elements, sizeof(nir_variable *)); _mesa_hash_table_insert(ht, var, elements); } else { elements = (nir_variable **) entry->data; } return elements; } static void lower_array(nir_builder *b, nir_intrinsic_instr *intr, nir_variable *var, struct hash_table *varyings) { b->cursor = nir_before_instr(&intr->instr); nir_variable **elements = get_array_elements(varyings, var, b->shader->info.stage); nir_ssa_def *vertex_index = NULL; unsigned elements_index = 0; unsigned xfb_offset = 0; unsigned io_offset = get_io_offset(b, nir_src_as_deref(intr->src[0]), var, &elements_index, &xfb_offset, &vertex_index); nir_variable *element = elements[elements_index]; if (!element) { element = nir_variable_clone(var, b->shader); element->data.location = var->data.location + io_offset; if (var->data.explicit_offset) element->data.offset = var->data.offset + xfb_offset; const struct glsl_type *type = glsl_without_array(element->type); /* This pass also splits matrices so we need give them a new type. */ if (glsl_type_is_matrix(type)) type = glsl_get_column_type(type); if (nir_is_per_vertex_io(var, b->shader->info.stage)) { type = glsl_array_type(type, glsl_get_length(element->type), glsl_get_explicit_stride(element->type)); } element->type = type; elements[elements_index] = element; nir_shader_add_variable(b->shader, element); } nir_deref_instr *element_deref = nir_build_deref_var(b, element); if (nir_is_per_vertex_io(var, b->shader->info.stage)) { assert(vertex_index); element_deref = nir_build_deref_array(b, element_deref, vertex_index); } nir_intrinsic_instr *element_intr = nir_intrinsic_instr_create(b->shader, intr->intrinsic); element_intr->num_components = intr->num_components; element_intr->src[0] = nir_src_for_ssa(&element_deref->dest.ssa); if (intr->intrinsic != nir_intrinsic_store_deref) { nir_ssa_dest_init(&element_intr->instr, &element_intr->dest, intr->num_components, intr->dest.ssa.bit_size, NULL); if (intr->intrinsic == nir_intrinsic_interp_deref_at_offset || intr->intrinsic == nir_intrinsic_interp_deref_at_sample || intr->intrinsic == nir_intrinsic_interp_deref_at_vertex) { nir_src_copy(&element_intr->src[1], &intr->src[1], &element_intr->instr); } nir_ssa_def_rewrite_uses(&intr->dest.ssa, nir_src_for_ssa(&element_intr->dest.ssa)); } else { nir_intrinsic_set_write_mask(element_intr, nir_intrinsic_write_mask(intr)); nir_src_copy(&element_intr->src[1], &intr->src[1], &element_intr->instr); } nir_builder_instr_insert(b, &element_intr->instr); /* Remove the old load intrinsic */ nir_instr_remove(&intr->instr); } static bool deref_has_indirect(nir_builder *b, nir_variable *var, nir_deref_path *path) { assert(path->path[0]->deref_type == nir_deref_type_var); nir_deref_instr **p = &path->path[1]; if (nir_is_per_vertex_io(var, b->shader->info.stage)) { p++; } for (; *p; p++) { if ((*p)->deref_type != nir_deref_type_array) continue; if (!nir_src_is_const((*p)->arr.index)) return true; } return false; } /* Creates a mask of locations that contains arrays that are indexed via * indirect indexing. */ static void create_indirects_mask(nir_shader *shader, BITSET_WORD *indirects, nir_variable_mode mode) { nir_foreach_function(function, shader) { if (function->impl) { nir_builder b; nir_builder_init(&b, function->impl); nir_foreach_block(block, function->impl) { nir_foreach_instr_safe(instr, block) { if (instr->type != nir_instr_type_intrinsic) continue; nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr); if (intr->intrinsic != nir_intrinsic_load_deref && intr->intrinsic != nir_intrinsic_store_deref && intr->intrinsic != nir_intrinsic_interp_deref_at_centroid && intr->intrinsic != nir_intrinsic_interp_deref_at_sample && intr->intrinsic != nir_intrinsic_interp_deref_at_offset && intr->intrinsic != nir_intrinsic_interp_deref_at_vertex) continue; nir_deref_instr *deref = nir_src_as_deref(intr->src[0]); if (deref->mode != mode) continue; nir_variable *var = nir_deref_instr_get_variable(deref); nir_deref_path path; nir_deref_path_init(&path, deref, NULL); int loc = var->data.location * 4 + var->data.location_frac; if (deref_has_indirect(&b, var, &path)) BITSET_SET(indirects, loc); nir_deref_path_finish(&path); } } } } } static void lower_io_arrays_to_elements(nir_shader *shader, nir_variable_mode mask, BITSET_WORD *indirects, struct hash_table *varyings, bool after_cross_stage_opts) { nir_foreach_function(function, shader) { if (function->impl) { nir_builder b; nir_builder_init(&b, function->impl); nir_foreach_block(block, function->impl) { nir_foreach_instr_safe(instr, block) { if (instr->type != nir_instr_type_intrinsic) continue; nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr); if (intr->intrinsic != nir_intrinsic_load_deref && intr->intrinsic != nir_intrinsic_store_deref && intr->intrinsic != nir_intrinsic_interp_deref_at_centroid && intr->intrinsic != nir_intrinsic_interp_deref_at_sample && intr->intrinsic != nir_intrinsic_interp_deref_at_offset && intr->intrinsic != nir_intrinsic_interp_deref_at_vertex) continue; nir_deref_instr *deref = nir_src_as_deref(intr->src[0]); if (!(deref->mode & mask)) continue; nir_variable *var = nir_deref_instr_get_variable(deref); /* Drivers assume compact arrays are, in fact, arrays. */ if (var->data.compact) continue; /* Skip indirects */ int loc = var->data.location * 4 + var->data.location_frac; if (BITSET_TEST(indirects, loc)) continue; nir_variable_mode mode = var->data.mode; const struct glsl_type *type = var->type; if (nir_is_per_vertex_io(var, b.shader->info.stage)) { assert(glsl_type_is_array(type)); type = glsl_get_array_element(type); } /* Skip types we cannot split. * * TODO: Add support for struct splitting. */ if ((!glsl_type_is_array(type) && !glsl_type_is_matrix(type))|| glsl_type_is_struct_or_ifc(glsl_without_array(type))) continue; /* Skip builtins */ if (!after_cross_stage_opts && var->data.location < VARYING_SLOT_VAR0 && var->data.location >= 0) continue; /* Don't bother splitting if we can't opt away any unused * elements. */ if (!after_cross_stage_opts && var->data.always_active_io) continue; switch (intr->intrinsic) { case nir_intrinsic_interp_deref_at_centroid: case nir_intrinsic_interp_deref_at_sample: case nir_intrinsic_interp_deref_at_offset: case nir_intrinsic_interp_deref_at_vertex: case nir_intrinsic_load_deref: case nir_intrinsic_store_deref: if ((mask & nir_var_shader_in && mode == nir_var_shader_in) || (mask & nir_var_shader_out && mode == nir_var_shader_out)) lower_array(&b, intr, var, varyings); break; default: break; } } } } } } void nir_lower_io_arrays_to_elements_no_indirects(nir_shader *shader, bool outputs_only) { struct hash_table *split_inputs = _mesa_pointer_hash_table_create(NULL); struct hash_table *split_outputs = _mesa_pointer_hash_table_create(NULL); BITSET_DECLARE(indirects, 4 * VARYING_SLOT_TESS_MAX) = {0}; lower_io_arrays_to_elements(shader, nir_var_shader_out, indirects, split_outputs, true); if (!outputs_only) { lower_io_arrays_to_elements(shader, nir_var_shader_in, indirects, split_inputs, true); /* Remove old input from the shaders inputs list */ hash_table_foreach(split_inputs, entry) { nir_variable *var = (nir_variable *) entry->key; exec_node_remove(&var->node); free(entry->data); } } /* Remove old output from the shaders outputs list */ hash_table_foreach(split_outputs, entry) { nir_variable *var = (nir_variable *) entry->key; exec_node_remove(&var->node); free(entry->data); } _mesa_hash_table_destroy(split_inputs, NULL); _mesa_hash_table_destroy(split_outputs, NULL); nir_remove_dead_derefs(shader); } void nir_lower_io_arrays_to_elements(nir_shader *producer, nir_shader *consumer) { struct hash_table *split_inputs = _mesa_pointer_hash_table_create(NULL); struct hash_table *split_outputs = _mesa_pointer_hash_table_create(NULL); BITSET_DECLARE(indirects, 4 * VARYING_SLOT_TESS_MAX) = {0}; create_indirects_mask(producer, indirects, nir_var_shader_out); create_indirects_mask(consumer, indirects, nir_var_shader_in); lower_io_arrays_to_elements(producer, nir_var_shader_out, indirects, split_outputs, false); lower_io_arrays_to_elements(consumer, nir_var_shader_in, indirects, split_inputs, false); /* Remove old input from the shaders inputs list */ hash_table_foreach(split_inputs, entry) { nir_variable *var = (nir_variable *) entry->key; exec_node_remove(&var->node); free(entry->data); } /* Remove old output from the shaders outputs list */ hash_table_foreach(split_outputs, entry) { nir_variable *var = (nir_variable *) entry->key; exec_node_remove(&var->node); free(entry->data); } _mesa_hash_table_destroy(split_inputs, NULL); _mesa_hash_table_destroy(split_outputs, NULL); nir_remove_dead_derefs(producer); nir_remove_dead_derefs(consumer); }