1 /* 2 * Copyright 2016 Broadcom 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS 21 * IN THE SOFTWARE. 22 */ 23 24 #include "nir.h" 25 #include "nir_builder.h" 26 27 /** @file nir_lower_io_to_scalar.c 28 * 29 * Replaces nir_load_input/nir_store_output operations with num_components != 30 * 1 with individual per-channel operations. 31 */ 32 33 static void 34 lower_load_input_to_scalar(nir_builder *b, nir_intrinsic_instr *intr) 35 { 36 b->cursor = nir_before_instr(&intr->instr); 37 38 assert(intr->dest.is_ssa); 39 40 nir_ssa_def *loads[4]; 41 42 for (unsigned i = 0; i < intr->num_components; i++) { 43 nir_intrinsic_instr *chan_intr = 44 nir_intrinsic_instr_create(b->shader, intr->intrinsic); 45 nir_ssa_dest_init(&chan_intr->instr, &chan_intr->dest, 46 1, intr->dest.ssa.bit_size, NULL); 47 chan_intr->num_components = 1; 48 49 nir_intrinsic_set_base(chan_intr, nir_intrinsic_base(intr)); 50 nir_intrinsic_set_component(chan_intr, nir_intrinsic_component(intr) + i); 51 /* offset */ 52 nir_src_copy(&chan_intr->src[0], &intr->src[0], chan_intr); 53 54 nir_builder_instr_insert(b, &chan_intr->instr); 55 56 loads[i] = &chan_intr->dest.ssa; 57 } 58 59 nir_ssa_def_rewrite_uses(&intr->dest.ssa, 60 nir_src_for_ssa(nir_vec(b, loads, 61 intr->num_components))); 62 nir_instr_remove(&intr->instr); 63 } 64 65 static void 66 lower_store_output_to_scalar(nir_builder *b, nir_intrinsic_instr *intr) 67 { 68 b->cursor = nir_before_instr(&intr->instr); 69 70 nir_ssa_def *value = nir_ssa_for_src(b, intr->src[0], intr->num_components); 71 72 for (unsigned i = 0; i < intr->num_components; i++) { 73 if (!(nir_intrinsic_write_mask(intr) & (1 << i))) 74 continue; 75 76 nir_intrinsic_instr *chan_intr = 77 nir_intrinsic_instr_create(b->shader, intr->intrinsic); 78 chan_intr->num_components = 1; 79 80 nir_intrinsic_set_base(chan_intr, nir_intrinsic_base(intr)); 81 nir_intrinsic_set_write_mask(chan_intr, 0x1); 82 nir_intrinsic_set_component(chan_intr, nir_intrinsic_component(intr) + i); 83 84 /* value */ 85 chan_intr->src[0] = nir_src_for_ssa(nir_channel(b, value, i)); 86 /* offset */ 87 nir_src_copy(&chan_intr->src[1], &intr->src[1], chan_intr); 88 89 nir_builder_instr_insert(b, &chan_intr->instr); 90 } 91 92 nir_instr_remove(&intr->instr); 93 } 94 95 void 96 nir_lower_io_to_scalar(nir_shader *shader, nir_variable_mode mask) 97 { 98 nir_foreach_function(function, shader) { 99 if (function->impl) { 100 nir_builder b; 101 nir_builder_init(&b, function->impl); 102 103 nir_foreach_block(block, function->impl) { 104 nir_foreach_instr_safe(instr, block) { 105 if (instr->type != nir_instr_type_intrinsic) 106 continue; 107 108 nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr); 109 110 if (intr->num_components == 1) 111 continue; 112 113 switch (intr->intrinsic) { 114 case nir_intrinsic_load_input: 115 if (mask & nir_var_shader_in) 116 lower_load_input_to_scalar(&b, intr); 117 break; 118 case nir_intrinsic_store_output: 119 if (mask & nir_var_shader_out) 120 lower_store_output_to_scalar(&b, intr); 121 break; 122 default: 123 break; 124 } 125 } 126 } 127 } 128 } 129 } 130 131 static nir_variable ** 132 get_channel_variables(struct hash_table *ht, nir_variable *var) 133 { 134 nir_variable **chan_vars; 135 struct hash_entry *entry = _mesa_hash_table_search(ht, var); 136 if (!entry) { 137 chan_vars = (nir_variable **) calloc(4, sizeof(nir_variable *)); 138 _mesa_hash_table_insert(ht, var, chan_vars); 139 } else { 140 chan_vars = (nir_variable **) entry->data; 141 } 142 143 return chan_vars; 144 } 145 146 /* 147 * This function differs from nir_deref_clone() in that it gets its type from 148 * the parent deref rather than our source deref. This is useful when splitting 149 * vectors because we want to use the scalar type of the new parent rather than 150 * then the old vector type. 151 */ 152 static nir_deref_array * 153 clone_deref_array(const nir_deref_array *darr, nir_deref *parent) 154 { 155 nir_deref_array *ndarr = nir_deref_array_create(parent); 156 157 ndarr->deref.type = glsl_get_array_element(parent->type); 158 if (darr->deref.child) 159 ndarr->deref.child = 160 &clone_deref_array(nir_deref_as_array(darr->deref.child), 161 &ndarr->deref)->deref; 162 163 ndarr->deref_array_type = darr->deref_array_type; 164 ndarr->base_offset = darr->base_offset; 165 if (ndarr->deref_array_type == nir_deref_array_type_indirect) 166 nir_src_copy(&ndarr->indirect, &darr->indirect, parent); 167 168 return ndarr; 169 } 170 171 static void 172 lower_load_to_scalar_early(nir_builder *b, nir_intrinsic_instr *intr, 173 nir_variable *var, struct hash_table *split_inputs, 174 struct hash_table *split_outputs) 175 { 176 b->cursor = nir_before_instr(&intr->instr); 177 178 assert(intr->dest.is_ssa); 179 180 nir_ssa_def *loads[4]; 181 182 nir_variable **chan_vars; 183 if (var->data.mode == nir_var_shader_in) { 184 chan_vars = get_channel_variables(split_inputs, var); 185 } else { 186 chan_vars = get_channel_variables(split_outputs, var); 187 } 188 189 for (unsigned i = 0; i < intr->num_components; i++) { 190 nir_variable *chan_var = chan_vars[var->data.location_frac + i]; 191 if (!chan_vars[var->data.location_frac + i]) { 192 chan_var = nir_variable_clone(var, b->shader); 193 chan_var->data.location_frac = var->data.location_frac + i; 194 chan_var->type = glsl_channel_type(chan_var->type); 195 196 chan_vars[var->data.location_frac + i] = chan_var; 197 198 nir_shader_add_variable(b->shader, chan_var); 199 } 200 201 nir_intrinsic_instr *chan_intr = 202 nir_intrinsic_instr_create(b->shader, intr->intrinsic); 203 nir_ssa_dest_init(&chan_intr->instr, &chan_intr->dest, 204 1, intr->dest.ssa.bit_size, NULL); 205 chan_intr->num_components = 1; 206 chan_intr->variables[0] = nir_deref_var_create(chan_intr, chan_var); 207 208 if (intr->variables[0]->deref.child) { 209 chan_intr->variables[0]->deref.child = 210 &clone_deref_array(nir_deref_as_array(intr->variables[0]->deref.child), 211 &chan_intr->variables[0]->deref)->deref; 212 } 213 214 if (intr->intrinsic == nir_intrinsic_interp_var_at_offset || 215 intr->intrinsic == nir_intrinsic_interp_var_at_sample) 216 nir_src_copy(chan_intr->src, intr->src, &chan_intr->instr); 217 218 nir_builder_instr_insert(b, &chan_intr->instr); 219 220 loads[i] = &chan_intr->dest.ssa; 221 } 222 223 nir_ssa_def_rewrite_uses(&intr->dest.ssa, 224 nir_src_for_ssa(nir_vec(b, loads, 225 intr->num_components))); 226 227 /* Remove the old load intrinsic */ 228 nir_instr_remove(&intr->instr); 229 } 230 231 static void 232 lower_store_output_to_scalar_early(nir_builder *b, nir_intrinsic_instr *intr, 233 nir_variable *var, 234 struct hash_table *split_outputs) 235 { 236 b->cursor = nir_before_instr(&intr->instr); 237 238 nir_ssa_def *value = nir_ssa_for_src(b, intr->src[0], intr->num_components); 239 240 nir_variable **chan_vars = get_channel_variables(split_outputs, var); 241 for (unsigned i = 0; i < intr->num_components; i++) { 242 if (!(nir_intrinsic_write_mask(intr) & (1 << i))) 243 continue; 244 245 nir_variable *chan_var = chan_vars[var->data.location_frac + i]; 246 if (!chan_vars[var->data.location_frac + i]) { 247 chan_var = nir_variable_clone(var, b->shader); 248 chan_var->data.location_frac = var->data.location_frac + i; 249 chan_var->type = glsl_channel_type(chan_var->type); 250 251 chan_vars[var->data.location_frac + i] = chan_var; 252 253 nir_shader_add_variable(b->shader, chan_var); 254 } 255 256 nir_intrinsic_instr *chan_intr = 257 nir_intrinsic_instr_create(b->shader, intr->intrinsic); 258 chan_intr->num_components = 1; 259 260 nir_intrinsic_set_write_mask(chan_intr, 0x1); 261 262 chan_intr->variables[0] = nir_deref_var_create(chan_intr, chan_var); 263 chan_intr->src[0] = nir_src_for_ssa(nir_channel(b, value, i)); 264 265 if (intr->variables[0]->deref.child) { 266 chan_intr->variables[0]->deref.child = 267 &clone_deref_array(nir_deref_as_array(intr->variables[0]->deref.child), 268 &chan_intr->variables[0]->deref)->deref; 269 } 270 271 nir_builder_instr_insert(b, &chan_intr->instr); 272 } 273 274 /* Remove the old store intrinsic */ 275 nir_instr_remove(&intr->instr); 276 } 277 278 /* 279 * This function is intended to be called earlier than nir_lower_io_to_scalar() 280 * i.e. before nir_lower_io() is called. 281 */ 282 void 283 nir_lower_io_to_scalar_early(nir_shader *shader, nir_variable_mode mask) 284 { 285 struct hash_table *split_inputs = 286 _mesa_hash_table_create(NULL, _mesa_hash_pointer, 287 _mesa_key_pointer_equal); 288 struct hash_table *split_outputs = 289 _mesa_hash_table_create(NULL, _mesa_hash_pointer, 290 _mesa_key_pointer_equal); 291 292 nir_foreach_function(function, shader) { 293 if (function->impl) { 294 nir_builder b; 295 nir_builder_init(&b, function->impl); 296 297 nir_foreach_block(block, function->impl) { 298 nir_foreach_instr_safe(instr, block) { 299 if (instr->type != nir_instr_type_intrinsic) 300 continue; 301 302 nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr); 303 304 if (intr->num_components == 1) 305 continue; 306 307 if (intr->intrinsic != nir_intrinsic_load_var && 308 intr->intrinsic != nir_intrinsic_store_var && 309 intr->intrinsic != nir_intrinsic_interp_var_at_centroid && 310 intr->intrinsic != nir_intrinsic_interp_var_at_sample && 311 intr->intrinsic != nir_intrinsic_interp_var_at_offset) 312 continue; 313 314 nir_variable *var = intr->variables[0]->var; 315 nir_variable_mode mode = var->data.mode; 316 317 /* TODO: add patch support */ 318 if (var->data.patch) 319 continue; 320 321 /* TODO: add doubles support */ 322 if (glsl_type_is_64bit(glsl_without_array(var->type))) 323 continue; 324 325 if (var->data.location < VARYING_SLOT_VAR0 && 326 var->data.location >= 0) 327 continue; 328 329 /* Don't bother splitting if we can't opt away any unused 330 * components. 331 */ 332 if (var->data.always_active_io) 333 continue; 334 335 /* Skip types we cannot split */ 336 if (glsl_type_is_matrix(glsl_without_array(var->type)) || 337 glsl_type_is_struct(glsl_without_array(var->type))) 338 continue; 339 340 switch (intr->intrinsic) { 341 case nir_intrinsic_interp_var_at_centroid: 342 case nir_intrinsic_interp_var_at_sample: 343 case nir_intrinsic_interp_var_at_offset: 344 case nir_intrinsic_load_var: 345 if ((mask & nir_var_shader_in && mode == nir_var_shader_in) || 346 (mask & nir_var_shader_out && mode == nir_var_shader_out)) 347 lower_load_to_scalar_early(&b, intr, var, split_inputs, 348 split_outputs); 349 break; 350 case nir_intrinsic_store_var: 351 if (mask & nir_var_shader_out && 352 mode == nir_var_shader_out) 353 lower_store_output_to_scalar_early(&b, intr, var, 354 split_outputs); 355 break; 356 default: 357 break; 358 } 359 } 360 } 361 } 362 } 363 364 /* Remove old input from the shaders inputs list */ 365 struct hash_entry *entry; 366 hash_table_foreach(split_inputs, entry) { 367 nir_variable *var = (nir_variable *) entry->key; 368 exec_node_remove(&var->node); 369 370 free(entry->data); 371 } 372 373 /* Remove old output from the shaders outputs list */ 374 hash_table_foreach(split_outputs, entry) { 375 nir_variable *var = (nir_variable *) entry->key; 376 exec_node_remove(&var->node); 377 378 free(entry->data); 379 } 380 381 _mesa_hash_table_destroy(split_inputs, NULL); 382 _mesa_hash_table_destroy(split_outputs, NULL); 383 } 384
