src/compiler/nir/nir.c

   1 /*
   2  * Copyright © 2014 Intel Corporation
   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  * Authors:
  24  *    Connor Abbott (cwabbott0@gmail.com)
  25  *
  26  */
  27
  28 #include "nir.h"
  29 #include "nir_control_flow_private.h"
  30 #include <assert.h>
  31
  32 nir_shader *
  33 nir_shader_create(void *mem_ctx,
  34                   gl_shader_stage stage,
  35                   const nir_shader_compiler_options *options)
  36 {
  37    nir_shader *shader = ralloc(mem_ctx, nir_shader);
  38
  39    exec_list_make_empty(&shader->uniforms);
  40    exec_list_make_empty(&shader->inputs);
  41    exec_list_make_empty(&shader->outputs);
  42    exec_list_make_empty(&shader->shared);
  43
  44    shader->options = options;
  45    memset(&shader->info, 0, sizeof(shader->info));
  46
  47    exec_list_make_empty(&shader->functions);
  48    exec_list_make_empty(&shader->registers);
  49    exec_list_make_empty(&shader->globals);
  50    exec_list_make_empty(&shader->system_values);
  51    shader->reg_alloc = 0;
  52
  53    shader->num_inputs = 0;
  54    shader->num_outputs = 0;
  55    shader->num_uniforms = 0;
  56    shader->num_shared = 0;
  57
  58    shader->stage = stage;
  59
  60    return shader;
  61 }
  62
  63 static nir_register *
  64 reg_create(void *mem_ctx, struct exec_list *list)
  65 {
  66    nir_register *reg = ralloc(mem_ctx, nir_register);
  67
  68    list_inithead(&reg->uses);
  69    list_inithead(&reg->defs);
  70    list_inithead(&reg->if_uses);
  71
  72    reg->num_components = 0;
  73    reg->bit_size = 32;
  74    reg->num_array_elems = 0;
  75    reg->is_packed = false;
  76    reg->name = NULL;
  77
  78    exec_list_push_tail(list, &reg->node);
  79
  80    return reg;
  81 }
  82
  83 nir_register *
  84 nir_global_reg_create(nir_shader *shader)
  85 {
  86    nir_register *reg = reg_create(shader, &shader->registers);
  87    reg->index = shader->reg_alloc++;
  88    reg->is_global = true;
  89
  90    return reg;
  91 }
  92
  93 nir_register *
  94 nir_local_reg_create(nir_function_impl *impl)
  95 {
  96    nir_register *reg = reg_create(ralloc_parent(impl), &impl->registers);
  97    reg->index = impl->reg_alloc++;
  98    reg->is_global = false;
  99
 100    return reg;
 101 }
 102
 103 void
 104 nir_reg_remove(nir_register *reg)
 105 {
 106    exec_node_remove(&reg->node);
 107 }
 108
 109 void
 110 nir_shader_add_variable(nir_shader *shader, nir_variable *var)
 111 {
 112    switch (var->data.mode) {
 113    case nir_var_all:
 114       assert(!"invalid mode");
 115       break;
 116
 117    case nir_var_local:
 118       assert(!"nir_shader_add_variable cannot be used for local variables");
 119       break;
 120
 121    case nir_var_param:
 122       assert(!"nir_shader_add_variable cannot be used for function parameters");
 123       break;
 124
 125    case nir_var_global:
 126       exec_list_push_tail(&shader->globals, &var->node);
 127       break;
 128
 129    case nir_var_shader_in:
 130       exec_list_push_tail(&shader->inputs, &var->node);
 131       break;
 132
 133    case nir_var_shader_out:
 134       exec_list_push_tail(&shader->outputs, &var->node);
 135       break;
 136
 137    case nir_var_uniform:
 138    case nir_var_shader_storage:
 139       exec_list_push_tail(&shader->uniforms, &var->node);
 140       break;
 141
 142    case nir_var_shared:
 143       assert(shader->stage == MESA_SHADER_COMPUTE);
 144       exec_list_push_tail(&shader->shared, &var->node);
 145       break;
 146
 147    case nir_var_system_value:
 148       exec_list_push_tail(&shader->system_values, &var->node);
 149       break;
 150    }
 151 }
 152
 153 nir_variable *
 154 nir_variable_create(nir_shader *shader, nir_variable_mode mode,
 155                     const struct glsl_type *type, const char *name)
 156 {
 157    nir_variable *var = rzalloc(shader, nir_variable);
 158    var->name = ralloc_strdup(var, name);
 159    var->type = type;
 160    var->data.mode = mode;
 161
 162    if ((mode == nir_var_shader_in && shader->stage != MESA_SHADER_VERTEX) ||
 163        (mode == nir_var_shader_out && shader->stage != MESA_SHADER_FRAGMENT))
 164       var->data.interpolation = INTERP_QUALIFIER_SMOOTH;
 165
 166    if (mode == nir_var_shader_in || mode == nir_var_uniform)
 167       var->data.read_only = true;
 168
 169    nir_shader_add_variable(shader, var);
 170
 171    return var;
 172 }
 173
 174 nir_variable *
 175 nir_local_variable_create(nir_function_impl *impl,
 176                           const struct glsl_type *type, const char *name)
 177 {
 178    nir_variable *var = rzalloc(impl->function->shader, nir_variable);
 179    var->name = ralloc_strdup(var, name);
 180    var->type = type;
 181    var->data.mode = nir_var_local;
 182
 183    nir_function_impl_add_variable(impl, var);
 184
 185    return var;
 186 }
 187
 188 nir_function *
 189 nir_function_create(nir_shader *shader, const char *name)
 190 {
 191    nir_function *func = ralloc(shader, nir_function);
 192
 193    exec_list_push_tail(&shader->functions, &func->node);
 194
 195    func->name = ralloc_strdup(func, name);
 196    func->shader = shader;
 197    func->num_params = 0;
 198    func->params = NULL;
 199    func->return_type = glsl_void_type();
 200    func->impl = NULL;
 201
 202    return func;
 203 }
 204
 205 void nir_src_copy(nir_src *dest, const nir_src *src, void *mem_ctx)
 206 {
 207    dest->is_ssa = src->is_ssa;
 208    if (src->is_ssa) {
 209       dest->ssa = src->ssa;
 210    } else {
 211       dest->reg.base_offset = src->reg.base_offset;
 212       dest->reg.reg = src->reg.reg;
 213       if (src->reg.indirect) {
 214          dest->reg.indirect = ralloc(mem_ctx, nir_src);
 215          nir_src_copy(dest->reg.indirect, src->reg.indirect, mem_ctx);
 216       } else {
 217          dest->reg.indirect = NULL;
 218       }
 219    }
 220 }
 221
 222 void nir_dest_copy(nir_dest *dest, const nir_dest *src, nir_instr *instr)
 223 {
 224    /* Copying an SSA definition makes no sense whatsoever. */
 225    assert(!src->is_ssa);
 226
 227    dest->is_ssa = false;
 228
 229    dest->reg.base_offset = src->reg.base_offset;
 230    dest->reg.reg = src->reg.reg;
 231    if (src->reg.indirect) {
 232       dest->reg.indirect = ralloc(instr, nir_src);
 233       nir_src_copy(dest->reg.indirect, src->reg.indirect, instr);
 234    } else {
 235       dest->reg.indirect = NULL;
 236    }
 237 }
 238
 239 void
 240 nir_alu_src_copy(nir_alu_src *dest, const nir_alu_src *src,
 241                  nir_alu_instr *instr)
 242 {
 243    nir_src_copy(&dest->src, &src->src, &instr->instr);
 244    dest->abs = src->abs;
 245    dest->negate = src->negate;
 246    for (unsigned i = 0; i < 4; i++)
 247       dest->swizzle[i] = src->swizzle[i];
 248 }
 249
 250 void
 251 nir_alu_dest_copy(nir_alu_dest *dest, const nir_alu_dest *src,
 252                   nir_alu_instr *instr)
 253 {
 254    nir_dest_copy(&dest->dest, &src->dest, &instr->instr);
 255    dest->write_mask = src->write_mask;
 256    dest->saturate = src->saturate;
 257 }
 258
 259
 260 static void
 261 cf_init(nir_cf_node *node, nir_cf_node_type type)
 262 {
 263    exec_node_init(&node->node);
 264    node->parent = NULL;
 265    node->type = type;
 266 }
 267
 268 nir_function_impl *
 269 nir_function_impl_create_bare(nir_shader *shader)
 270 {
 271    nir_function_impl *impl = ralloc(shader, nir_function_impl);
 272
 273    impl->function = NULL;
 274
 275    cf_init(&impl->cf_node, nir_cf_node_function);
 276
 277    exec_list_make_empty(&impl->body);
 278    exec_list_make_empty(&impl->registers);
 279    exec_list_make_empty(&impl->locals);
 280    impl->num_params = 0;
 281    impl->params = NULL;
 282    impl->return_var = NULL;
 283    impl->reg_alloc = 0;
 284    impl->ssa_alloc = 0;
 285    impl->valid_metadata = nir_metadata_none;
 286
 287    /* create start & end blocks */
 288    nir_block *start_block = nir_block_create(shader);
 289    nir_block *end_block = nir_block_create(shader);
 290    start_block->cf_node.parent = &impl->cf_node;
 291    end_block->cf_node.parent = &impl->cf_node;
 292    impl->end_block = end_block;
 293
 294    exec_list_push_tail(&impl->body, &start_block->cf_node.node);
 295
 296    start_block->successors[0] = end_block;
 297    _mesa_set_add(end_block->predecessors, start_block);
 298    return impl;
 299 }
 300
 301 nir_function_impl *
 302 nir_function_impl_create(nir_function *function)
 303 {
 304    assert(function->impl == NULL);
 305
 306    nir_function_impl *impl = nir_function_impl_create_bare(function->shader);
 307
 308    function->impl = impl;
 309    impl->function = function;
 310
 311    impl->num_params = function->num_params;
 312    impl->params = ralloc_array(function->shader,
 313                                nir_variable *, impl->num_params);
 314
 315    for (unsigned i = 0; i < impl->num_params; i++) {
 316       impl->params[i] = rzalloc(function->shader, nir_variable);
 317       impl->params[i]->type = function->params[i].type;
 318       impl->params[i]->data.mode = nir_var_param;
 319       impl->params[i]->data.location = i;
 320    }
 321
 322    if (!glsl_type_is_void(function->return_type)) {
 323       impl->return_var = rzalloc(function->shader, nir_variable);
 324       impl->return_var->type = function->return_type;
 325       impl->return_var->data.mode = nir_var_param;
 326       impl->return_var->data.location = -1;
 327    } else {
 328       impl->return_var = NULL;
 329    }
 330
 331    return impl;
 332 }
 333
 334 nir_block *
 335 nir_block_create(nir_shader *shader)
 336 {
 337    nir_block *block = ralloc(shader, nir_block);
 338
 339    cf_init(&block->cf_node, nir_cf_node_block);
 340
 341    block->successors[0] = block->successors[1] = NULL;
 342    block->predecessors = _mesa_set_create(block, _mesa_hash_pointer,
 343                                           _mesa_key_pointer_equal);
 344    block->imm_dom = NULL;
 345    /* XXX maybe it would be worth it to defer allocation?  This
 346     * way it doesn't get allocated for shader ref's that never run
 347     * nir_calc_dominance?  For example, state-tracker creates an
 348     * initial IR, clones that, runs appropriate lowering pass, passes
 349     * to driver which does common lowering/opt, and then stores ref
 350     * which is later used to do state specific lowering and futher
 351     * opt.  Do any of the references not need dominance metadata?
 352     */
 353    block->dom_frontier = _mesa_set_create(block, _mesa_hash_pointer,
 354                                           _mesa_key_pointer_equal);
 355
 356    exec_list_make_empty(&block->instr_list);
 357
 358    return block;
 359 }
 360
 361 static inline void
 362 src_init(nir_src *src)
 363 {
 364    src->is_ssa = false;
 365    src->reg.reg = NULL;
 366    src->reg.indirect = NULL;
 367    src->reg.base_offset = 0;
 368 }
 369
 370 nir_if *
 371 nir_if_create(nir_shader *shader)
 372 {
 373    nir_if *if_stmt = ralloc(shader, nir_if);
 374
 375    cf_init(&if_stmt->cf_node, nir_cf_node_if);
 376    src_init(&if_stmt->condition);
 377
 378    nir_block *then = nir_block_create(shader);
 379    exec_list_make_empty(&if_stmt->then_list);
 380    exec_list_push_tail(&if_stmt->then_list, &then->cf_node.node);
 381    then->cf_node.parent = &if_stmt->cf_node;
 382
 383    nir_block *else_stmt = nir_block_create(shader);
 384    exec_list_make_empty(&if_stmt->else_list);
 385    exec_list_push_tail(&if_stmt->else_list, &else_stmt->cf_node.node);
 386    else_stmt->cf_node.parent = &if_stmt->cf_node;
 387
 388    return if_stmt;
 389 }
 390
 391 nir_loop *
 392 nir_loop_create(nir_shader *shader)
 393 {
 394    nir_loop *loop = ralloc(shader, nir_loop);
 395
 396    cf_init(&loop->cf_node, nir_cf_node_loop);
 397
 398    nir_block *body = nir_block_create(shader);
 399    exec_list_make_empty(&loop->body);
 400    exec_list_push_tail(&loop->body, &body->cf_node.node);
 401    body->cf_node.parent = &loop->cf_node;
 402
 403    body->successors[0] = body;
 404    _mesa_set_add(body->predecessors, body);
 405
 406    return loop;
 407 }
 408
 409 static void
 410 instr_init(nir_instr *instr, nir_instr_type type)
 411 {
 412    instr->type = type;
 413    instr->block = NULL;
 414    exec_node_init(&instr->node);
 415 }
 416
 417 static void
 418 dest_init(nir_dest *dest)
 419 {
 420    dest->is_ssa = false;
 421    dest->reg.reg = NULL;
 422    dest->reg.indirect = NULL;
 423    dest->reg.base_offset = 0;
 424 }
 425
 426 static void
 427 alu_dest_init(nir_alu_dest *dest)
 428 {
 429    dest_init(&dest->dest);
 430    dest->saturate = false;
 431    dest->write_mask = 0xf;
 432 }
 433
 434 static void
 435 alu_src_init(nir_alu_src *src)
 436 {
 437    src_init(&src->src);
 438    src->abs = src->negate = false;
 439    src->swizzle[0] = 0;
 440    src->swizzle[1] = 1;
 441    src->swizzle[2] = 2;
 442    src->swizzle[3] = 3;
 443 }
 444
 445 nir_alu_instr *
 446 nir_alu_instr_create(nir_shader *shader, nir_op op)
 447 {
 448    unsigned num_srcs = nir_op_infos[op].num_inputs;
 449    nir_alu_instr *instr =
 450       ralloc_size(shader,
 451                   sizeof(nir_alu_instr) + num_srcs * sizeof(nir_alu_src));
 452
 453    instr_init(&instr->instr, nir_instr_type_alu);
 454    instr->op = op;
 455    alu_dest_init(&instr->dest);
 456    for (unsigned i = 0; i < num_srcs; i++)
 457       alu_src_init(&instr->src[i]);
 458
 459    return instr;
 460 }
 461
 462 nir_jump_instr *
 463 nir_jump_instr_create(nir_shader *shader, nir_jump_type type)
 464 {
 465    nir_jump_instr *instr = ralloc(shader, nir_jump_instr);
 466    instr_init(&instr->instr, nir_instr_type_jump);
 467    instr->type = type;
 468    return instr;
 469 }
 470
 471 nir_load_const_instr *
 472 nir_load_const_instr_create(nir_shader *shader, unsigned num_components,
 473                             unsigned bit_size)
 474 {
 475    nir_load_const_instr *instr = ralloc(shader, nir_load_const_instr);
 476    instr_init(&instr->instr, nir_instr_type_load_const);
 477
 478    nir_ssa_def_init(&instr->instr, &instr->def, num_components, bit_size, NULL);
 479
 480    return instr;
 481 }
 482
 483 nir_intrinsic_instr *
 484 nir_intrinsic_instr_create(nir_shader *shader, nir_intrinsic_op op)
 485 {
 486    unsigned num_srcs = nir_intrinsic_infos[op].num_srcs;
 487    nir_intrinsic_instr *instr =
 488       ralloc_size(shader,
 489                   sizeof(nir_intrinsic_instr) + num_srcs * sizeof(nir_src));
 490
 491    instr_init(&instr->instr, nir_instr_type_intrinsic);
 492    instr->intrinsic = op;
 493
 494    if (nir_intrinsic_infos[op].has_dest)
 495       dest_init(&instr->dest);
 496
 497    for (unsigned i = 0; i < num_srcs; i++)
 498       src_init(&instr->src[i]);
 499
 500    return instr;
 501 }
 502
 503 nir_call_instr *
 504 nir_call_instr_create(nir_shader *shader, nir_function *callee)
 505 {
 506    nir_call_instr *instr = ralloc(shader, nir_call_instr);
 507    instr_init(&instr->instr, nir_instr_type_call);
 508
 509    instr->callee = callee;
 510    instr->num_params = callee->num_params;
 511    instr->params = ralloc_array(instr, nir_deref_var *, instr->num_params);
 512    instr->return_deref = NULL;
 513
 514    return instr;
 515 }
 516
 517 nir_tex_instr *
 518 nir_tex_instr_create(nir_shader *shader, unsigned num_srcs)
 519 {
 520    nir_tex_instr *instr = rzalloc(shader, nir_tex_instr);
 521    instr_init(&instr->instr, nir_instr_type_tex);
 522
 523    dest_init(&instr->dest);
 524
 525    instr->num_srcs = num_srcs;
 526    instr->src = ralloc_array(instr, nir_tex_src, num_srcs);
 527    for (unsigned i = 0; i < num_srcs; i++)
 528       src_init(&instr->src[i].src);
 529
 530    instr->texture_index = 0;
 531    instr->texture_array_size = 0;
 532    instr->texture = NULL;
 533    instr->sampler_index = 0;
 534    instr->sampler = NULL;
 535
 536    return instr;
 537 }
 538
 539 nir_phi_instr *
 540 nir_phi_instr_create(nir_shader *shader)
 541 {
 542    nir_phi_instr *instr = ralloc(shader, nir_phi_instr);
 543    instr_init(&instr->instr, nir_instr_type_phi);
 544
 545    dest_init(&instr->dest);
 546    exec_list_make_empty(&instr->srcs);
 547    return instr;
 548 }
 549
 550 nir_parallel_copy_instr *
 551 nir_parallel_copy_instr_create(nir_shader *shader)
 552 {
 553    nir_parallel_copy_instr *instr = ralloc(shader, nir_parallel_copy_instr);
 554    instr_init(&instr->instr, nir_instr_type_parallel_copy);
 555
 556    exec_list_make_empty(&instr->entries);
 557
 558    return instr;
 559 }
 560
 561 nir_ssa_undef_instr *
 562 nir_ssa_undef_instr_create(nir_shader *shader,
 563                            unsigned num_components,
 564                            unsigned bit_size)
 565 {
 566    nir_ssa_undef_instr *instr = ralloc(shader, nir_ssa_undef_instr);
 567    instr_init(&instr->instr, nir_instr_type_ssa_undef);
 568
 569    nir_ssa_def_init(&instr->instr, &instr->def, num_components, bit_size, NULL);
 570
 571    return instr;
 572 }
 573
 574 nir_deref_var *
 575 nir_deref_var_create(void *mem_ctx, nir_variable *var)
 576 {
 577    nir_deref_var *deref = ralloc(mem_ctx, nir_deref_var);
 578    deref->deref.deref_type = nir_deref_type_var;
 579    deref->deref.child = NULL;
 580    deref->deref.type = var->type;
 581    deref->var = var;
 582    return deref;
 583 }
 584
 585 nir_deref_array *
 586 nir_deref_array_create(void *mem_ctx)
 587 {
 588    nir_deref_array *deref = ralloc(mem_ctx, nir_deref_array);
 589    deref->deref.deref_type = nir_deref_type_array;
 590    deref->deref.child = NULL;
 591    deref->deref_array_type = nir_deref_array_type_direct;
 592    src_init(&deref->indirect);
 593    deref->base_offset = 0;
 594    return deref;
 595 }
 596
 597 nir_deref_struct *
 598 nir_deref_struct_create(void *mem_ctx, unsigned field_index)
 599 {
 600    nir_deref_struct *deref = ralloc(mem_ctx, nir_deref_struct);
 601    deref->deref.deref_type = nir_deref_type_struct;
 602    deref->deref.child = NULL;
 603    deref->index = field_index;
 604    return deref;
 605 }
 606
 607 static nir_deref_var *
 608 copy_deref_var(void *mem_ctx, nir_deref_var *deref)
 609 {
 610    nir_deref_var *ret = nir_deref_var_create(mem_ctx, deref->var);
 611    ret->deref.type = deref->deref.type;
 612    if (deref->deref.child)
 613       ret->deref.child = nir_copy_deref(ret, deref->deref.child);
 614    return ret;
 615 }
 616
 617 static nir_deref_array *
 618 copy_deref_array(void *mem_ctx, nir_deref_array *deref)
 619 {
 620    nir_deref_array *ret = nir_deref_array_create(mem_ctx);
 621    ret->base_offset = deref->base_offset;
 622    ret->deref_array_type = deref->deref_array_type;
 623    if (deref->deref_array_type == nir_deref_array_type_indirect) {
 624       nir_src_copy(&ret->indirect, &deref->indirect, mem_ctx);
 625    }
 626    ret->deref.type = deref->deref.type;
 627    if (deref->deref.child)
 628       ret->deref.child = nir_copy_deref(ret, deref->deref.child);
 629    return ret;
 630 }
 631
 632 static nir_deref_struct *
 633 copy_deref_struct(void *mem_ctx, nir_deref_struct *deref)
 634 {
 635    nir_deref_struct *ret = nir_deref_struct_create(mem_ctx, deref->index);
 636    ret->deref.type = deref->deref.type;
 637    if (deref->deref.child)
 638       ret->deref.child = nir_copy_deref(ret, deref->deref.child);
 639    return ret;
 640 }
 641
 642 nir_deref *
 643 nir_copy_deref(void *mem_ctx, nir_deref *deref)
 644 {
 645    if (deref == NULL)
 646       return NULL;
 647
 648    switch (deref->deref_type) {
 649    case nir_deref_type_var:
 650       return &copy_deref_var(mem_ctx, nir_deref_as_var(deref))->deref;
 651    case nir_deref_type_array:
 652       return &copy_deref_array(mem_ctx, nir_deref_as_array(deref))->deref;
 653    case nir_deref_type_struct:
 654       return &copy_deref_struct(mem_ctx, nir_deref_as_struct(deref))->deref;
 655    default:
 656       unreachable("Invalid dereference type");
 657    }
 658
 659    return NULL;
 660 }
 661
 662 /* Returns a load_const instruction that represents the constant
 663  * initializer for the given deref chain.  The caller is responsible for
 664  * ensuring that there actually is a constant initializer.
 665  */
 666 nir_load_const_instr *
 667 nir_deref_get_const_initializer_load(nir_shader *shader, nir_deref_var *deref)
 668 {
 669    nir_constant *constant = deref->var->constant_initializer;
 670    assert(constant);
 671
 672    const nir_deref *tail = &deref->deref;
 673    unsigned matrix_offset = 0;
 674    while (tail->child) {
 675       switch (tail->child->deref_type) {
 676       case nir_deref_type_array: {
 677          nir_deref_array *arr = nir_deref_as_array(tail->child);
 678          assert(arr->deref_array_type == nir_deref_array_type_direct);
 679          if (glsl_type_is_matrix(tail->type)) {
 680             assert(arr->deref.child == NULL);
 681             matrix_offset = arr->base_offset;
 682          } else {
 683             constant = constant->elements[arr->base_offset];
 684          }
 685          break;
 686       }
 687
 688       case nir_deref_type_struct: {
 689          constant = constant->elements[nir_deref_as_struct(tail->child)->index];
 690          break;
 691       }
 692
 693       default:
 694          unreachable("Invalid deref child type");
 695       }
 696
 697       tail = tail->child;
 698    }
 699
 700    unsigned bit_size = glsl_get_bit_size(tail->type);
 701    nir_load_const_instr *load =
 702       nir_load_const_instr_create(shader, glsl_get_vector_elements(tail->type),
 703                                   bit_size);
 704
 705    matrix_offset *= load->def.num_components;
 706    for (unsigned i = 0; i < load->def.num_components; i++) {
 707       switch (glsl_get_base_type(tail->type)) {
 708       case GLSL_TYPE_FLOAT:
 709       case GLSL_TYPE_INT:
 710       case GLSL_TYPE_UINT:
 711          load->value.u32[i] = constant->value.u[matrix_offset + i];
 712          break;
 713       case GLSL_TYPE_DOUBLE:
 714          load->value.f64[i] = constant->value.d[matrix_offset + i];
 715          break;
 716       case GLSL_TYPE_BOOL:
 717          load->value.u32[i] = constant->value.b[matrix_offset + i] ?
 718                              NIR_TRUE : NIR_FALSE;
 719          break;
 720       default:
 721          unreachable("Invalid immediate type");
 722       }
 723    }
 724
 725    return load;
 726 }
 727
 728 nir_function_impl *
 729 nir_cf_node_get_function(nir_cf_node *node)
 730 {
 731    while (node->type != nir_cf_node_function) {
 732       node = node->parent;
 733    }
 734
 735    return nir_cf_node_as_function(node);
 736 }
 737
 738 /* Reduces a cursor by trying to convert everything to after and trying to
 739  * go up to block granularity when possible.
 740  */
 741 static nir_cursor
 742 reduce_cursor(nir_cursor cursor)
 743 {
 744    switch (cursor.option) {
 745    case nir_cursor_before_block:
 746       assert(nir_cf_node_prev(&cursor.block->cf_node) == NULL ||
 747              nir_cf_node_prev(&cursor.block->cf_node)->type != nir_cf_node_block);
 748       if (exec_list_is_empty(&cursor.block->instr_list)) {
 749          /* Empty block.  After is as good as before. */
 750          cursor.option = nir_cursor_after_block;
 751       }
 752       return cursor;
 753
 754    case nir_cursor_after_block:
 755       return cursor;
 756
 757    case nir_cursor_before_instr: {
 758       nir_instr *prev_instr = nir_instr_prev(cursor.instr);
 759       if (prev_instr) {
 760          /* Before this instruction is after the previous */
 761          cursor.instr = prev_instr;
 762          cursor.option = nir_cursor_after_instr;
 763       } else {
 764          /* No previous instruction.  Switch to before block */
 765          cursor.block = cursor.instr->block;
 766          cursor.option = nir_cursor_before_block;
 767       }
 768       return reduce_cursor(cursor);
 769    }
 770
 771    case nir_cursor_after_instr:
 772       if (nir_instr_next(cursor.instr) == NULL) {
 773          /* This is the last instruction, switch to after block */
 774          cursor.option = nir_cursor_after_block;
 775          cursor.block = cursor.instr->block;
 776       }
 777       return cursor;
 778
 779    default:
 780       unreachable("Inavlid cursor option");
 781    }
 782 }
 783
 784 bool
 785 nir_cursors_equal(nir_cursor a, nir_cursor b)
 786 {
 787    /* Reduced cursors should be unique */
 788    a = reduce_cursor(a);
 789    b = reduce_cursor(b);
 790
 791    return a.block == b.block && a.option == b.option;
 792 }
 793
 794 static bool
 795 add_use_cb(nir_src *src, void *state)
 796 {
 797    nir_instr *instr = state;
 798
 799    src->parent_instr = instr;
 800    list_addtail(&src->use_link,
 801                 src->is_ssa ? &src->ssa->uses : &src->reg.reg->uses);
 802
 803    return true;
 804 }
 805
 806 static bool
 807 add_ssa_def_cb(nir_ssa_def *def, void *state)
 808 {
 809    nir_instr *instr = state;
 810
 811    if (instr->block && def->index == UINT_MAX) {
 812       nir_function_impl *impl =
 813          nir_cf_node_get_function(&instr->block->cf_node);
 814
 815       def->index = impl->ssa_alloc++;
 816    }
 817
 818    return true;
 819 }
 820
 821 static bool
 822 add_reg_def_cb(nir_dest *dest, void *state)
 823 {
 824    nir_instr *instr = state;
 825
 826    if (!dest->is_ssa) {
 827       dest->reg.parent_instr = instr;
 828       list_addtail(&dest->reg.def_link, &dest->reg.reg->defs);
 829    }
 830
 831    return true;
 832 }
 833
 834 static void
 835 add_defs_uses(nir_instr *instr)
 836 {
 837    nir_foreach_src(instr, add_use_cb, instr);
 838    nir_foreach_dest(instr, add_reg_def_cb, instr);
 839    nir_foreach_ssa_def(instr, add_ssa_def_cb, instr);
 840 }
 841
 842 void
 843 nir_instr_insert(nir_cursor cursor, nir_instr *instr)
 844 {
 845    switch (cursor.option) {
 846    case nir_cursor_before_block:
 847       /* Only allow inserting jumps into empty blocks. */
 848       if (instr->type == nir_instr_type_jump)
 849          assert(exec_list_is_empty(&cursor.block->instr_list));
 850
 851       instr->block = cursor.block;
 852       add_defs_uses(instr);
 853       exec_list_push_head(&cursor.block->instr_list, &instr->node);
 854       break;
 855    case nir_cursor_after_block: {
 856       /* Inserting instructions after a jump is illegal. */
 857       nir_instr *last = nir_block_last_instr(cursor.block);
 858       assert(last == NULL || last->type != nir_instr_type_jump);
 859       (void) last;
 860
 861       instr->block = cursor.block;
 862       add_defs_uses(instr);
 863       exec_list_push_tail(&cursor.block->instr_list, &instr->node);
 864       break;
 865    }
 866    case nir_cursor_before_instr:
 867       assert(instr->type != nir_instr_type_jump);
 868       instr->block = cursor.instr->block;
 869       add_defs_uses(instr);
 870       exec_node_insert_node_before(&cursor.instr->node, &instr->node);
 871       break;
 872    case nir_cursor_after_instr:
 873       /* Inserting instructions after a jump is illegal. */
 874       assert(cursor.instr->type != nir_instr_type_jump);
 875
 876       /* Only allow inserting jumps at the end of the block. */
 877       if (instr->type == nir_instr_type_jump)
 878          assert(cursor.instr == nir_block_last_instr(cursor.instr->block));
 879
 880       instr->block = cursor.instr->block;
 881       add_defs_uses(instr);
 882       exec_node_insert_after(&cursor.instr->node, &instr->node);
 883       break;
 884    }
 885
 886    if (instr->type == nir_instr_type_jump)
 887       nir_handle_add_jump(instr->block);
 888 }
 889
 890 static bool
 891 src_is_valid(const nir_src *src)
 892 {
 893    return src->is_ssa ? (src->ssa != NULL) : (src->reg.reg != NULL);
 894 }
 895
 896 static bool
 897 remove_use_cb(nir_src *src, void *state)
 898 {
 899    (void) state;
 900
 901    if (src_is_valid(src))
 902       list_del(&src->use_link);
 903
 904    return true;
 905 }
 906
 907 static bool
 908 remove_def_cb(nir_dest *dest, void *state)
 909 {
 910    (void) state;
 911
 912    if (!dest->is_ssa)
 913       list_del(&dest->reg.def_link);
 914
 915    return true;
 916 }
 917
 918 static void
 919 remove_defs_uses(nir_instr *instr)
 920 {
 921    nir_foreach_dest(instr, remove_def_cb, instr);
 922    nir_foreach_src(instr, remove_use_cb, instr);
 923 }
 924
 925 void nir_instr_remove(nir_instr *instr)
 926 {
 927    remove_defs_uses(instr);
 928    exec_node_remove(&instr->node);
 929
 930    if (instr->type == nir_instr_type_jump) {
 931       nir_jump_instr *jump_instr = nir_instr_as_jump(instr);
 932       nir_handle_remove_jump(instr->block, jump_instr->type);
 933    }
 934 }
 935
 936 /*@}*/
 937
 938 void
 939 nir_index_local_regs(nir_function_impl *impl)
 940 {
 941    unsigned index = 0;
 942    foreach_list_typed(nir_register, reg, node, &impl->registers) {
 943       reg->index = index++;
 944    }
 945    impl->reg_alloc = index;
 946 }
 947
 948 void
 949 nir_index_global_regs(nir_shader *shader)
 950 {
 951    unsigned index = 0;
 952    foreach_list_typed(nir_register, reg, node, &shader->registers) {
 953       reg->index = index++;
 954    }
 955    shader->reg_alloc = index;
 956 }
 957
 958 static bool
 959 visit_alu_dest(nir_alu_instr *instr, nir_foreach_dest_cb cb, void *state)
 960 {
 961    return cb(&instr->dest.dest, state);
 962 }
 963
 964 static bool
 965 visit_intrinsic_dest(nir_intrinsic_instr *instr, nir_foreach_dest_cb cb,
 966                      void *state)
 967 {
 968    if (nir_intrinsic_infos[instr->intrinsic].has_dest)
 969       return cb(&instr->dest, state);
 970
 971    return true;
 972 }
 973
 974 static bool
 975 visit_texture_dest(nir_tex_instr *instr, nir_foreach_dest_cb cb,
 976                    void *state)
 977 {
 978    return cb(&instr->dest, state);
 979 }
 980
 981 static bool
 982 visit_phi_dest(nir_phi_instr *instr, nir_foreach_dest_cb cb, void *state)
 983 {
 984    return cb(&instr->dest, state);
 985 }
 986
 987 static bool
 988 visit_parallel_copy_dest(nir_parallel_copy_instr *instr,
 989                          nir_foreach_dest_cb cb, void *state)
 990 {
 991    nir_foreach_parallel_copy_entry(entry, instr) {
 992       if (!cb(&entry->dest, state))
 993          return false;
 994    }
 995
 996    return true;
 997 }
 998
 999 bool
1000 nir_foreach_dest(nir_instr *instr, nir_foreach_dest_cb cb, void *state)
1001 {
1002    switch (instr->type) {
1003    case nir_instr_type_alu:
1004       return visit_alu_dest(nir_instr_as_alu(instr), cb, state);
1005    case nir_instr_type_intrinsic:
1006       return visit_intrinsic_dest(nir_instr_as_intrinsic(instr), cb, state);
1007    case nir_instr_type_tex:
1008       return visit_texture_dest(nir_instr_as_tex(instr), cb, state);
1009    case nir_instr_type_phi:
1010       return visit_phi_dest(nir_instr_as_phi(instr), cb, state);
1011    case nir_instr_type_parallel_copy:
1012       return visit_parallel_copy_dest(nir_instr_as_parallel_copy(instr),
1013                                       cb, state);
1014
1015    case nir_instr_type_load_const:
1016    case nir_instr_type_ssa_undef:
1017    case nir_instr_type_call:
1018    case nir_instr_type_jump:
1019       break;
1020
1021    default:
1022       unreachable("Invalid instruction type");
1023       break;
1024    }
1025
1026    return true;
1027 }
1028
1029 struct foreach_ssa_def_state {
1030    nir_foreach_ssa_def_cb cb;
1031    void *client_state;
1032 };
1033
1034 static inline bool
1035 nir_ssa_def_visitor(nir_dest *dest, void *void_state)
1036 {
1037    struct foreach_ssa_def_state *state = void_state;
1038
1039    if (dest->is_ssa)
1040       return state->cb(&dest->ssa, state->client_state);
1041    else
1042       return true;
1043 }
1044
1045 bool
1046 nir_foreach_ssa_def(nir_instr *instr, nir_foreach_ssa_def_cb cb, void *state)
1047 {
1048    switch (instr->type) {
1049    case nir_instr_type_alu:
1050    case nir_instr_type_tex:
1051    case nir_instr_type_intrinsic:
1052    case nir_instr_type_phi:
1053    case nir_instr_type_parallel_copy: {
1054       struct foreach_ssa_def_state foreach_state = {cb, state};
1055       return nir_foreach_dest(instr, nir_ssa_def_visitor, &foreach_state);
1056    }
1057
1058    case nir_instr_type_load_const:
1059       return cb(&nir_instr_as_load_const(instr)->def, state);
1060    case nir_instr_type_ssa_undef:
1061       return cb(&nir_instr_as_ssa_undef(instr)->def, state);
1062    case nir_instr_type_call:
1063    case nir_instr_type_jump:
1064       return true;
1065    default:
1066       unreachable("Invalid instruction type");
1067    }
1068 }
1069
1070 static bool
1071 visit_src(nir_src *src, nir_foreach_src_cb cb, void *state)
1072 {
1073    if (!cb(src, state))
1074       return false;
1075    if (!src->is_ssa && src->reg.indirect)
1076       return cb(src->reg.indirect, state);
1077    return true;
1078 }
1079
1080 static bool
1081 visit_deref_array_src(nir_deref_array *deref, nir_foreach_src_cb cb,
1082                       void *state)
1083 {
1084    if (deref->deref_array_type == nir_deref_array_type_indirect)
1085       return visit_src(&deref->indirect, cb, state);
1086    return true;
1087 }
1088
1089 static bool
1090 visit_deref_src(nir_deref_var *deref, nir_foreach_src_cb cb, void *state)
1091 {
1092    nir_deref *cur = &deref->deref;
1093    while (cur != NULL) {
1094       if (cur->deref_type == nir_deref_type_array) {
1095          if (!visit_deref_array_src(nir_deref_as_array(cur), cb, state))
1096             return false;
1097       }
1098
1099       cur = cur->child;
1100    }
1101
1102    return true;
1103 }
1104
1105 static bool
1106 visit_alu_src(nir_alu_instr *instr, nir_foreach_src_cb cb, void *state)
1107 {
1108    for (unsigned i = 0; i < nir_op_infos[instr->op].num_inputs; i++)
1109       if (!visit_src(&instr->src[i].src, cb, state))
1110          return false;
1111
1112    return true;
1113 }
1114
1115 static bool
1116 visit_tex_src(nir_tex_instr *instr, nir_foreach_src_cb cb, void *state)
1117 {
1118    for (unsigned i = 0; i < instr->num_srcs; i++) {
1119       if (!visit_src(&instr->src[i].src, cb, state))
1120          return false;
1121    }
1122
1123    if (instr->texture != NULL) {
1124       if (!visit_deref_src(instr->texture, cb, state))
1125          return false;
1126    }
1127
1128    if (instr->sampler != NULL) {
1129       if (!visit_deref_src(instr->sampler, cb, state))
1130          return false;
1131    }
1132
1133    return true;
1134 }
1135
1136 static bool
1137 visit_intrinsic_src(nir_intrinsic_instr *instr, nir_foreach_src_cb cb,
1138                     void *state)
1139 {
1140    unsigned num_srcs = nir_intrinsic_infos[instr->intrinsic].num_srcs;
1141    for (unsigned i = 0; i < num_srcs; i++) {
1142       if (!visit_src(&instr->src[i], cb, state))
1143          return false;
1144    }
1145
1146    unsigned num_vars =
1147       nir_intrinsic_infos[instr->intrinsic].num_variables;
1148    for (unsigned i = 0; i < num_vars; i++) {
1149       if (!visit_deref_src(instr->variables[i], cb, state))
1150          return false;
1151    }
1152
1153    return true;
1154 }
1155
1156 static bool
1157 visit_phi_src(nir_phi_instr *instr, nir_foreach_src_cb cb, void *state)
1158 {
1159    nir_foreach_phi_src(src, instr) {
1160       if (!visit_src(&src->src, cb, state))
1161          return false;
1162    }
1163
1164    return true;
1165 }
1166
1167 static bool
1168 visit_parallel_copy_src(nir_parallel_copy_instr *instr,
1169                         nir_foreach_src_cb cb, void *state)
1170 {
1171    nir_foreach_parallel_copy_entry(entry, instr) {
1172       if (!visit_src(&entry->src, cb, state))
1173          return false;
1174    }
1175
1176    return true;
1177 }
1178
1179 typedef struct {
1180    void *state;
1181    nir_foreach_src_cb cb;
1182 } visit_dest_indirect_state;
1183
1184 static bool
1185 visit_dest_indirect(nir_dest *dest, void *_state)
1186 {
1187    visit_dest_indirect_state *state = (visit_dest_indirect_state *) _state;
1188
1189    if (!dest->is_ssa && dest->reg.indirect)
1190       return state->cb(dest->reg.indirect, state->state);
1191
1192    return true;
1193 }
1194
1195 bool
1196 nir_foreach_src(nir_instr *instr, nir_foreach_src_cb cb, void *state)
1197 {
1198    switch (instr->type) {
1199    case nir_instr_type_alu:
1200       if (!visit_alu_src(nir_instr_as_alu(instr), cb, state))
1201          return false;
1202       break;
1203    case nir_instr_type_intrinsic:
1204       if (!visit_intrinsic_src(nir_instr_as_intrinsic(instr), cb, state))
1205          return false;
1206       break;
1207    case nir_instr_type_tex:
1208       if (!visit_tex_src(nir_instr_as_tex(instr), cb, state))
1209          return false;
1210       break;
1211    case nir_instr_type_call:
1212       /* Call instructions have no regular sources */
1213       break;
1214    case nir_instr_type_load_const:
1215       /* Constant load instructions have no regular sources */
1216       break;
1217    case nir_instr_type_phi:
1218       if (!visit_phi_src(nir_instr_as_phi(instr), cb, state))
1219          return false;
1220       break;
1221    case nir_instr_type_parallel_copy:
1222       if (!visit_parallel_copy_src(nir_instr_as_parallel_copy(instr),
1223                                    cb, state))
1224          return false;
1225       break;
1226    case nir_instr_type_jump:
1227    case nir_instr_type_ssa_undef:
1228       return true;
1229
1230    default:
1231       unreachable("Invalid instruction type");
1232       break;
1233    }
1234
1235    visit_dest_indirect_state dest_state;
1236    dest_state.state = state;
1237    dest_state.cb = cb;
1238    return nir_foreach_dest(instr, visit_dest_indirect, &dest_state);
1239 }
1240
1241 nir_const_value *
1242 nir_src_as_const_value(nir_src src)
1243 {
1244    if (!src.is_ssa)
1245       return NULL;
1246
1247    if (src.ssa->parent_instr->type != nir_instr_type_load_const)
1248       return NULL;
1249
1250    nir_load_const_instr *load = nir_instr_as_load_const(src.ssa->parent_instr);
1251
1252    return &load->value;
1253 }
1254
1255 /**
1256  * Returns true if the source is known to be dynamically uniform. Otherwise it
1257  * returns false which means it may or may not be dynamically uniform but it
1258  * can't be determined.
1259  */
1260 bool
1261 nir_src_is_dynamically_uniform(nir_src src)
1262 {
1263    if (!src.is_ssa)
1264       return false;
1265
1266    /* Constants are trivially dynamically uniform */
1267    if (src.ssa->parent_instr->type == nir_instr_type_load_const)
1268       return true;
1269
1270    /* As are uniform variables */
1271    if (src.ssa->parent_instr->type == nir_instr_type_intrinsic) {
1272       nir_intrinsic_instr *intr = nir_instr_as_intrinsic(src.ssa->parent_instr);
1273
1274       if (intr->intrinsic == nir_intrinsic_load_uniform)
1275          return true;
1276    }
1277
1278    /* XXX: this could have many more tests, such as when a sampler function is
1279     * called with dynamically uniform arguments.
1280     */
1281    return false;
1282 }
1283
1284 static void
1285 src_remove_all_uses(nir_src *src)
1286 {
1287    for (; src; src = src->is_ssa ? NULL : src->reg.indirect) {
1288       if (!src_is_valid(src))
1289          continue;
1290
1291       list_del(&src->use_link);
1292    }
1293 }
1294
1295 static void
1296 src_add_all_uses(nir_src *src, nir_instr *parent_instr, nir_if *parent_if)
1297 {
1298    for (; src; src = src->is_ssa ? NULL : src->reg.indirect) {
1299       if (!src_is_valid(src))
1300          continue;
1301
1302       if (parent_instr) {
1303          src->parent_instr = parent_instr;
1304          if (src->is_ssa)
1305             list_addtail(&src->use_link, &src->ssa->uses);
1306          else
1307             list_addtail(&src->use_link, &src->reg.reg->uses);
1308       } else {
1309          assert(parent_if);
1310          src->parent_if = parent_if;
1311          if (src->is_ssa)
1312             list_addtail(&src->use_link, &src->ssa->if_uses);
1313          else
1314             list_addtail(&src->use_link, &src->reg.reg->if_uses);
1315       }
1316    }
1317 }
1318
1319 void
1320 nir_instr_rewrite_src(nir_instr *instr, nir_src *src, nir_src new_src)
1321 {
1322    assert(!src_is_valid(src) || src->parent_instr == instr);
1323
1324    src_remove_all_uses(src);
1325    *src = new_src;
1326    src_add_all_uses(src, instr, NULL);
1327 }
1328
1329 void
1330 nir_instr_move_src(nir_instr *dest_instr, nir_src *dest, nir_src *src)
1331 {
1332    assert(!src_is_valid(dest) || dest->parent_instr == dest_instr);
1333
1334    src_remove_all_uses(dest);
1335    src_remove_all_uses(src);
1336    *dest = *src;
1337    *src = NIR_SRC_INIT;
1338    src_add_all_uses(dest, dest_instr, NULL);
1339 }
1340
1341 void
1342 nir_if_rewrite_condition(nir_if *if_stmt, nir_src new_src)
1343 {
1344    nir_src *src = &if_stmt->condition;
1345    assert(!src_is_valid(src) || src->parent_if == if_stmt);
1346
1347    src_remove_all_uses(src);
1348    *src = new_src;
1349    src_add_all_uses(src, NULL, if_stmt);
1350 }
1351
1352 void
1353 nir_instr_rewrite_dest(nir_instr *instr, nir_dest *dest, nir_dest new_dest)
1354 {
1355    if (dest->is_ssa) {
1356       /* We can only overwrite an SSA destination if it has no uses. */
1357       assert(list_empty(&dest->ssa.uses) && list_empty(&dest->ssa.if_uses));
1358    } else {
1359       list_del(&dest->reg.def_link);
1360       if (dest->reg.indirect)
1361          src_remove_all_uses(dest->reg.indirect);
1362    }
1363
1364    /* We can't re-write with an SSA def */
1365    assert(!new_dest.is_ssa);
1366
1367    nir_dest_copy(dest, &new_dest, instr);
1368
1369    dest->reg.parent_instr = instr;
1370    list_addtail(&dest->reg.def_link, &new_dest.reg.reg->defs);
1371
1372    if (dest->reg.indirect)
1373       src_add_all_uses(dest->reg.indirect, instr, NULL);
1374 }
1375
1376 /* note: does *not* take ownership of 'name' */
1377 void
1378 nir_ssa_def_init(nir_instr *instr, nir_ssa_def *def,
1379                  unsigned num_components,
1380                  unsigned bit_size, const char *name)
1381 {
1382    def->name = ralloc_strdup(instr, name);
1383    def->parent_instr = instr;
1384    list_inithead(&def->uses);
1385    list_inithead(&def->if_uses);
1386    def->num_components = num_components;
1387    def->bit_size = bit_size;
1388
1389    if (instr->block) {
1390       nir_function_impl *impl =
1391          nir_cf_node_get_function(&instr->block->cf_node);
1392
1393       def->index = impl->ssa_alloc++;
1394    } else {
1395       def->index = UINT_MAX;
1396    }
1397 }
1398
1399 /* note: does *not* take ownership of 'name' */
1400 void
1401 nir_ssa_dest_init(nir_instr *instr, nir_dest *dest,
1402                  unsigned num_components, unsigned bit_size,
1403                  const char *name)
1404 {
1405    dest->is_ssa = true;
1406    nir_ssa_def_init(instr, &dest->ssa, num_components, bit_size, name);
1407 }
1408
1409 void
1410 nir_ssa_def_rewrite_uses(nir_ssa_def *def, nir_src new_src)
1411 {
1412    assert(!new_src.is_ssa || def != new_src.ssa);
1413
1414    nir_foreach_use_safe(use_src, def)
1415       nir_instr_rewrite_src(use_src->parent_instr, use_src, new_src);
1416
1417    nir_foreach_if_use_safe(use_src, def)
1418       nir_if_rewrite_condition(use_src->parent_if, new_src);
1419 }
1420
1421 static bool
1422 is_instr_between(nir_instr *start, nir_instr *end, nir_instr *between)
1423 {
1424    assert(start->block == end->block);
1425
1426    if (between->block != start->block)
1427       return false;
1428
1429    /* Search backwards looking for "between" */
1430    while (start != end) {
1431       if (between == end)
1432          return true;
1433
1434       end = nir_instr_prev(end);
1435       assert(end);
1436    }
1437
1438    return false;
1439 }
1440
1441 /* Replaces all uses of the given SSA def with the given source but only if
1442  * the use comes after the after_me instruction.  This can be useful if you
1443  * are emitting code to fix up the result of some instruction: you can freely
1444  * use the result in that code and then call rewrite_uses_after and pass the
1445  * last fixup instruction as after_me and it will replace all of the uses you
1446  * want without touching the fixup code.
1447  *
1448  * This function assumes that after_me is in the same block as
1449  * def->parent_instr and that after_me comes after def->parent_instr.
1450  */
1451 void
1452 nir_ssa_def_rewrite_uses_after(nir_ssa_def *def, nir_src new_src,
1453                                nir_instr *after_me)
1454 {
1455    assert(!new_src.is_ssa || def != new_src.ssa);
1456
1457    nir_foreach_use_safe(use_src, def) {
1458       assert(use_src->parent_instr != def->parent_instr);
1459       /* Since def already dominates all of its uses, the only way a use can
1460        * not be dominated by after_me is if it is between def and after_me in
1461        * the instruction list.
1462        */
1463       if (!is_instr_between(def->parent_instr, after_me, use_src->parent_instr))
1464          nir_instr_rewrite_src(use_src->parent_instr, use_src, new_src);
1465    }
1466
1467    nir_foreach_if_use_safe(use_src, def)
1468       nir_if_rewrite_condition(use_src->parent_if, new_src);
1469 }
1470
1471 uint8_t
1472 nir_ssa_def_components_read(nir_ssa_def *def)
1473 {
1474    uint8_t read_mask = 0;
1475    nir_foreach_use(use, def) {
1476       if (use->parent_instr->type == nir_instr_type_alu) {
1477          nir_alu_instr *alu = nir_instr_as_alu(use->parent_instr);
1478          nir_alu_src *alu_src = exec_node_data(nir_alu_src, use, src);
1479          int src_idx = alu_src - &alu->src[0];
1480          assert(src_idx >= 0 && src_idx < nir_op_infos[alu->op].num_inputs);
1481
1482          for (unsigned c = 0; c < 4; c++) {
1483             if (!nir_alu_instr_channel_used(alu, src_idx, c))
1484                continue;
1485
1486             read_mask |= (1 << alu_src->swizzle[c]);
1487          }
1488       } else {
1489          return (1 << def->num_components) - 1;
1490       }
1491    }
1492
1493    return read_mask;
1494 }
1495
1496 nir_block *
1497 nir_block_cf_tree_next(nir_block *block)
1498 {
1499    if (block == NULL) {
1500       /* nir_foreach_block_safe() will call this function on a NULL block
1501        * after the last iteration, but it won't use the result so just return
1502        * NULL here.
1503        */
1504       return NULL;
1505    }
1506
1507    nir_cf_node *cf_next = nir_cf_node_next(&block->cf_node);
1508    if (cf_next)
1509       return nir_cf_node_cf_tree_first(cf_next);
1510
1511    nir_cf_node *parent = block->cf_node.parent;
1512
1513    switch (parent->type) {
1514    case nir_cf_node_if: {
1515       /* Are we at the end of the if? Go to the beginning of the else */
1516       nir_if *if_stmt = nir_cf_node_as_if(parent);
1517       if (&block->cf_node == nir_if_last_then_node(if_stmt))
1518          return nir_cf_node_as_block(nir_if_first_else_node(if_stmt));
1519
1520       assert(&block->cf_node == nir_if_last_else_node(if_stmt));
1521       /* fall through */
1522    }
1523
1524    case nir_cf_node_loop:
1525       return nir_cf_node_as_block(nir_cf_node_next(parent));
1526
1527    case nir_cf_node_function:
1528       return NULL;
1529
1530    default:
1531       unreachable("unknown cf node type");
1532    }
1533 }
1534
1535 nir_block *
1536 nir_block_cf_tree_prev(nir_block *block)
1537 {
1538    if (block == NULL) {
1539       /* do this for consistency with nir_block_cf_tree_next() */
1540       return NULL;
1541    }
1542
1543    nir_cf_node *cf_prev = nir_cf_node_prev(&block->cf_node);
1544    if (cf_prev)
1545       return nir_cf_node_cf_tree_last(cf_prev);
1546
1547    nir_cf_node *parent = block->cf_node.parent;
1548
1549    switch (parent->type) {
1550    case nir_cf_node_if: {
1551       /* Are we at the beginning of the else? Go to the end of the if */
1552       nir_if *if_stmt = nir_cf_node_as_if(parent);
1553       if (&block->cf_node == nir_if_first_else_node(if_stmt))
1554          return nir_cf_node_as_block(nir_if_last_then_node(if_stmt));
1555
1556       assert(&block->cf_node == nir_if_first_then_node(if_stmt));
1557       /* fall through */
1558    }
1559
1560    case nir_cf_node_loop:
1561       return nir_cf_node_as_block(nir_cf_node_prev(parent));
1562
1563    case nir_cf_node_function:
1564       return NULL;
1565
1566    default:
1567       unreachable("unknown cf node type");
1568    }
1569 }
1570
1571 nir_block *nir_cf_node_cf_tree_first(nir_cf_node *node)
1572 {
1573    switch (node->type) {
1574    case nir_cf_node_function: {
1575       nir_function_impl *impl = nir_cf_node_as_function(node);
1576       return nir_start_block(impl);
1577    }
1578
1579    case nir_cf_node_if: {
1580       nir_if *if_stmt = nir_cf_node_as_if(node);
1581       return nir_cf_node_as_block(nir_if_first_then_node(if_stmt));
1582    }
1583
1584    case nir_cf_node_loop: {
1585       nir_loop *loop = nir_cf_node_as_loop(node);
1586       return nir_cf_node_as_block(nir_loop_first_cf_node(loop));
1587    }
1588
1589    case nir_cf_node_block: {
1590       return nir_cf_node_as_block(node);
1591    }
1592
1593    default:
1594       unreachable("unknown node type");
1595    }
1596 }
1597
1598 nir_block *nir_cf_node_cf_tree_last(nir_cf_node *node)
1599 {
1600    switch (node->type) {
1601    case nir_cf_node_function: {
1602       nir_function_impl *impl = nir_cf_node_as_function(node);
1603       return nir_impl_last_block(impl);
1604    }
1605
1606    case nir_cf_node_if: {
1607       nir_if *if_stmt = nir_cf_node_as_if(node);
1608       return nir_cf_node_as_block(nir_if_last_else_node(if_stmt));
1609    }
1610
1611    case nir_cf_node_loop: {
1612       nir_loop *loop = nir_cf_node_as_loop(node);
1613       return nir_cf_node_as_block(nir_loop_last_cf_node(loop));
1614    }
1615
1616    case nir_cf_node_block: {
1617       return nir_cf_node_as_block(node);
1618    }
1619
1620    default:
1621       unreachable("unknown node type");
1622    }
1623 }
1624
1625 nir_block *nir_cf_node_cf_tree_next(nir_cf_node *node)
1626 {
1627    if (node->type == nir_cf_node_block)
1628       return nir_cf_node_cf_tree_first(nir_cf_node_next(node));
1629    else if (node->type == nir_cf_node_function)
1630       return NULL;
1631    else
1632       return nir_cf_node_as_block(nir_cf_node_next(node));
1633 }
1634
1635 nir_if *
1636 nir_block_get_following_if(nir_block *block)
1637 {
1638    if (exec_node_is_tail_sentinel(&block->cf_node.node))
1639       return NULL;
1640
1641    if (nir_cf_node_is_last(&block->cf_node))
1642       return NULL;
1643
1644    nir_cf_node *next_node = nir_cf_node_next(&block->cf_node);
1645
1646    if (next_node->type != nir_cf_node_if)
1647       return NULL;
1648
1649    return nir_cf_node_as_if(next_node);
1650 }
1651
1652 nir_loop *
1653 nir_block_get_following_loop(nir_block *block)
1654 {
1655    if (exec_node_is_tail_sentinel(&block->cf_node.node))
1656       return NULL;
1657
1658    if (nir_cf_node_is_last(&block->cf_node))
1659       return NULL;
1660
1661    nir_cf_node *next_node = nir_cf_node_next(&block->cf_node);
1662
1663    if (next_node->type != nir_cf_node_loop)
1664       return NULL;
1665
1666    return nir_cf_node_as_loop(next_node);
1667 }
1668
1669 void
1670 nir_index_blocks(nir_function_impl *impl)
1671 {
1672    unsigned index = 0;
1673
1674    if (impl->valid_metadata & nir_metadata_block_index)
1675       return;
1676
1677    nir_foreach_block(block, impl) {
1678       block->index = index++;
1679    }
1680
1681    impl->num_blocks = index;
1682 }
1683
1684 static bool
1685 index_ssa_def_cb(nir_ssa_def *def, void *state)
1686 {
1687    unsigned *index = (unsigned *) state;
1688    def->index = (*index)++;
1689
1690    return true;
1691 }
1692
1693 /**
1694  * The indices are applied top-to-bottom which has the very nice property
1695  * that, if A dominates B, then A->index <= B->index.
1696  */
1697 void
1698 nir_index_ssa_defs(nir_function_impl *impl)
1699 {
1700    unsigned index = 0;
1701
1702    nir_foreach_block(block, impl) {
1703       nir_foreach_instr(instr, block)
1704          nir_foreach_ssa_def(instr, index_ssa_def_cb, &index);
1705    }
1706
1707    impl->ssa_alloc = index;
1708 }
1709
1710 /**
1711  * The indices are applied top-to-bottom which has the very nice property
1712  * that, if A dominates B, then A->index <= B->index.
1713  */
1714 unsigned
1715 nir_index_instrs(nir_function_impl *impl)
1716 {
1717    unsigned index = 0;
1718
1719    nir_foreach_block(block, impl) {
1720       nir_foreach_instr(instr, block)
1721          instr->index = index++;
1722    }
1723
1724    return index;
1725 }
1726
1727 nir_intrinsic_op
1728 nir_intrinsic_from_system_value(gl_system_value val)
1729 {
1730    switch (val) {
1731    case SYSTEM_VALUE_VERTEX_ID:
1732       return nir_intrinsic_load_vertex_id;
1733    case SYSTEM_VALUE_INSTANCE_ID:
1734       return nir_intrinsic_load_instance_id;
1735    case SYSTEM_VALUE_DRAW_ID:
1736       return nir_intrinsic_load_draw_id;
1737    case SYSTEM_VALUE_BASE_INSTANCE:
1738       return nir_intrinsic_load_base_instance;
1739    case SYSTEM_VALUE_VERTEX_ID_ZERO_BASE:
1740       return nir_intrinsic_load_vertex_id_zero_base;
1741    case SYSTEM_VALUE_BASE_VERTEX:
1742       return nir_intrinsic_load_base_vertex;
1743    case SYSTEM_VALUE_INVOCATION_ID:
1744       return nir_intrinsic_load_invocation_id;
1745    case SYSTEM_VALUE_FRONT_FACE:
1746       return nir_intrinsic_load_front_face;
1747    case SYSTEM_VALUE_SAMPLE_ID:
1748       return nir_intrinsic_load_sample_id;
1749    case SYSTEM_VALUE_SAMPLE_POS:
1750       return nir_intrinsic_load_sample_pos;
1751    case SYSTEM_VALUE_SAMPLE_MASK_IN:
1752       return nir_intrinsic_load_sample_mask_in;
1753    case SYSTEM_VALUE_LOCAL_INVOCATION_ID:
1754       return nir_intrinsic_load_local_invocation_id;
1755    case SYSTEM_VALUE_LOCAL_INVOCATION_INDEX:
1756       return nir_intrinsic_load_local_invocation_index;
1757    case SYSTEM_VALUE_WORK_GROUP_ID:
1758       return nir_intrinsic_load_work_group_id;
1759    case SYSTEM_VALUE_NUM_WORK_GROUPS:
1760       return nir_intrinsic_load_num_work_groups;
1761    case SYSTEM_VALUE_PRIMITIVE_ID:
1762       return nir_intrinsic_load_primitive_id;
1763    case SYSTEM_VALUE_TESS_COORD:
1764       return nir_intrinsic_load_tess_coord;
1765    case SYSTEM_VALUE_TESS_LEVEL_OUTER:
1766       return nir_intrinsic_load_tess_level_outer;
1767    case SYSTEM_VALUE_TESS_LEVEL_INNER:
1768       return nir_intrinsic_load_tess_level_inner;
1769    case SYSTEM_VALUE_VERTICES_IN:
1770       return nir_intrinsic_load_patch_vertices_in;
1771    case SYSTEM_VALUE_HELPER_INVOCATION:
1772       return nir_intrinsic_load_helper_invocation;
1773    default:
1774       unreachable("system value does not directly correspond to intrinsic");
1775    }
1776 }
1777
1778 gl_system_value
1779 nir_system_value_from_intrinsic(nir_intrinsic_op intrin)
1780 {
1781    switch (intrin) {
1782    case nir_intrinsic_load_vertex_id:
1783       return SYSTEM_VALUE_VERTEX_ID;
1784    case nir_intrinsic_load_instance_id:
1785       return SYSTEM_VALUE_INSTANCE_ID;
1786    case nir_intrinsic_load_draw_id:
1787       return SYSTEM_VALUE_DRAW_ID;
1788    case nir_intrinsic_load_base_instance:
1789       return SYSTEM_VALUE_BASE_INSTANCE;
1790    case nir_intrinsic_load_vertex_id_zero_base:
1791       return SYSTEM_VALUE_VERTEX_ID_ZERO_BASE;
1792    case nir_intrinsic_load_base_vertex:
1793       return SYSTEM_VALUE_BASE_VERTEX;
1794    case nir_intrinsic_load_invocation_id:
1795       return SYSTEM_VALUE_INVOCATION_ID;
1796    case nir_intrinsic_load_front_face:
1797       return SYSTEM_VALUE_FRONT_FACE;
1798    case nir_intrinsic_load_sample_id:
1799       return SYSTEM_VALUE_SAMPLE_ID;
1800    case nir_intrinsic_load_sample_pos:
1801       return SYSTEM_VALUE_SAMPLE_POS;
1802    case nir_intrinsic_load_sample_mask_in:
1803       return SYSTEM_VALUE_SAMPLE_MASK_IN;
1804    case nir_intrinsic_load_local_invocation_id:
1805       return SYSTEM_VALUE_LOCAL_INVOCATION_ID;
1806    case nir_intrinsic_load_local_invocation_index:
1807       return SYSTEM_VALUE_LOCAL_INVOCATION_INDEX;
1808    case nir_intrinsic_load_num_work_groups:
1809       return SYSTEM_VALUE_NUM_WORK_GROUPS;
1810    case nir_intrinsic_load_work_group_id:
1811       return SYSTEM_VALUE_WORK_GROUP_ID;
1812    case nir_intrinsic_load_primitive_id:
1813       return SYSTEM_VALUE_PRIMITIVE_ID;
1814    case nir_intrinsic_load_tess_coord:
1815       return SYSTEM_VALUE_TESS_COORD;
1816    case nir_intrinsic_load_tess_level_outer:
1817       return SYSTEM_VALUE_TESS_LEVEL_OUTER;
1818    case nir_intrinsic_load_tess_level_inner:
1819       return SYSTEM_VALUE_TESS_LEVEL_INNER;
1820    case nir_intrinsic_load_patch_vertices_in:
1821       return SYSTEM_VALUE_VERTICES_IN;
1822    case nir_intrinsic_load_helper_invocation:
1823       return SYSTEM_VALUE_HELPER_INVOCATION;
1824    default:
1825       unreachable("intrinsic doesn't produce a system value");
1826    }
1827 }