src/glsl/nir/nir_validate.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 <assert.h>
  30
  31 /*
  32  * This file checks for invalid IR indicating a bug somewhere in the compiler.
  33  */
  34
  35 /*
  36  * Per-register validation state.
  37  */
  38
  39 typedef struct {
  40    /*
  41     * equivalent to the uses and defs in nir_register, but built up by the
  42     * validator. At the end, we verify that the sets have the same entries.
  43     */
  44    struct set *uses, *defs;
  45    nir_function_impl *where_defined; /* NULL for global registers */
  46 } reg_validate_state;
  47
  48 typedef struct {
  49    /* map of register -> validation state (struct above) */
  50    struct hash_table *regs;
  51
  52    /* the current instruction being validated */
  53    nir_instr *instr;
  54
  55    /* the current basic block being validated */
  56    nir_block *block;
  57
  58    /* the current if statement being validated */
  59    nir_if *if_stmt;
  60
  61    /* the parent of the current cf node being visited */
  62    nir_cf_node *parent_node;
  63
  64    /* the current function implementation being validated */
  65    nir_function_impl *impl;
  66
  67    /* map of SSA value -> function implementation where it is defined */
  68    struct hash_table *ssa_defs;
  69
  70    /* map of local variable -> function implementation where it is defined */
  71    struct hash_table *var_defs;
  72 } validate_state;
  73
  74 static void validate_src(nir_src *src, validate_state *state);
  75
  76 static void
  77 validate_reg_src(nir_reg_src *src, validate_state *state)
  78 {
  79    assert(src->reg != NULL);
  80
  81    struct set_entry *entry =
  82       _mesa_set_search(src->reg->uses, _mesa_hash_pointer(state->instr),
  83                        state->instr);
  84    assert(entry && "use not in nir_register.uses");
  85
  86    struct hash_entry *entry2;
  87    entry2 = _mesa_hash_table_search(state->regs, src->reg);
  88
  89    assert(entry2);
  90
  91    reg_validate_state *reg_state = (reg_validate_state *) entry2->data;
  92    _mesa_set_add(reg_state->uses, _mesa_hash_pointer(state->instr),
  93                  state->instr);
  94
  95    if (!src->reg->is_global) {
  96       assert(reg_state->where_defined == state->impl &&
  97              "using a register declared in a different function");
  98    }
  99
 100    assert((src->reg->num_array_elems == 0 ||
 101           src->base_offset < src->reg->num_array_elems) &&
 102           "definitely out-of-bounds array access");
 103
 104    if (src->indirect) {
 105       assert(src->reg->num_array_elems != 0);
 106       assert((src->indirect->is_ssa || src->indirect->reg.indirect == NULL) &&
 107              "only one level of indirection allowed");
 108       validate_src(src->indirect, state);
 109    }
 110 }
 111
 112 static void
 113 validate_ssa_src(nir_ssa_def *def, validate_state *state)
 114 {
 115    assert(def != NULL);
 116
 117    struct hash_entry *entry = _mesa_hash_table_search(state->ssa_defs, def);
 118
 119    assert(entry);
 120
 121    assert((nir_function_impl *) entry->data == state->impl &&
 122           "using an SSA value defined in a different function");
 123
 124    struct set_entry *entry2;
 125
 126    entry2 = _mesa_set_search(def->uses, _mesa_hash_pointer(state->instr),
 127                               state->instr);
 128
 129    assert(entry2 && "SSA use missing");
 130
 131    /* TODO validate that the use is dominated by the definition */
 132 }
 133
 134 static void
 135 validate_src(nir_src *src, validate_state *state)
 136 {
 137    if (src->is_ssa)
 138       validate_ssa_src(src->ssa, state);
 139    else
 140       validate_reg_src(&src->reg, state);
 141 }
 142
 143 static void
 144 validate_alu_src(nir_alu_instr *instr, unsigned index, validate_state *state)
 145 {
 146    nir_alu_src *src = &instr->src[index];
 147
 148    unsigned num_components;
 149    if (src->src.is_ssa)
 150       num_components = src->src.ssa->num_components;
 151    else {
 152       if (src->src.reg.reg->is_packed)
 153          num_components = 4; /* can't check anything */
 154       else
 155          num_components = src->src.reg.reg->num_components;
 156    }
 157    for (unsigned i = 0; i < 4; i++) {
 158       assert(src->swizzle[i] < 4);
 159
 160       if (nir_alu_instr_channel_used(instr, index, i))
 161          assert(src->swizzle[i] < num_components);
 162    }
 163
 164    validate_src(&src->src, state);
 165 }
 166
 167 static void
 168 validate_reg_dest(nir_reg_dest *dest, validate_state *state)
 169 {
 170    assert(dest->reg != NULL);
 171
 172    struct set_entry *entry =
 173       _mesa_set_search(dest->reg->defs, _mesa_hash_pointer(state->instr),
 174                        state->instr);
 175    assert(entry && "definition not in nir_register.defs");
 176
 177    struct hash_entry *entry2;
 178    entry2 = _mesa_hash_table_search(state->regs, dest->reg);
 179
 180    assert(entry2);
 181
 182    reg_validate_state *reg_state = (reg_validate_state *) entry2->data;
 183    _mesa_set_add(reg_state->defs, _mesa_hash_pointer(state->instr),
 184                  state->instr);
 185
 186    if (!dest->reg->is_global) {
 187       assert(reg_state->where_defined == state->impl &&
 188              "writing to a register declared in a different function");
 189    }
 190
 191    assert((dest->reg->num_array_elems == 0 ||
 192           dest->base_offset < dest->reg->num_array_elems) &&
 193           "definitely out-of-bounds array access");
 194
 195    if (dest->indirect) {
 196       assert(dest->reg->num_array_elems != 0);
 197       assert((dest->indirect->is_ssa || dest->indirect->reg.indirect == NULL) &&
 198              "only one level of indirection allowed");
 199       validate_src(dest->indirect, state);
 200    }
 201 }
 202
 203 static void
 204 validate_ssa_def(nir_ssa_def *def, validate_state *state)
 205 {
 206    assert(def->num_components <= 4);
 207    _mesa_hash_table_insert(state->ssa_defs, def, state->impl);
 208 }
 209
 210 static void
 211 validate_dest(nir_dest *dest, validate_state *state)
 212 {
 213    if (dest->is_ssa)
 214       validate_ssa_def(&dest->ssa, state);
 215    else
 216       validate_reg_dest(&dest->reg, state);
 217 }
 218
 219 static void
 220 validate_alu_dest(nir_alu_dest *dest, validate_state *state)
 221 {
 222    unsigned dest_size =
 223       dest->dest.is_ssa ? dest->dest.ssa.num_components
 224                         : dest->dest.reg.reg->num_components;
 225    bool is_packed = !dest->dest.is_ssa && dest->dest.reg.reg->is_packed;
 226    /*
 227     * validate that the instruction doesn't write to components not in the
 228     * register/SSA value
 229     */
 230    assert(is_packed || !(dest->write_mask & ~((1 << dest_size) - 1)));
 231    validate_dest(&dest->dest, state);
 232 }
 233
 234 static void
 235 validate_alu_instr(nir_alu_instr *instr, validate_state *state)
 236 {
 237    assert(instr->op < nir_num_opcodes);
 238
 239    validate_alu_dest(&instr->dest, state);
 240
 241    for (unsigned i = 0; i < nir_op_infos[instr->op].num_inputs; i++) {
 242       validate_alu_src(instr, i, state);
 243    }
 244
 245    if (instr->has_predicate)
 246       validate_src(&instr->predicate, state);
 247 }
 248
 249 static void
 250 validate_deref_chain(nir_deref *deref, validate_state *state)
 251 {
 252    nir_deref *parent = NULL;
 253    while (deref != NULL) {
 254       switch (deref->deref_type) {
 255       case nir_deref_type_array:
 256          assert(deref->type == glsl_get_array_element(parent->type));
 257          if (nir_deref_as_array(deref)->has_indirect)
 258             validate_src(&nir_deref_as_array(deref)->indirect, state);
 259          break;
 260
 261       case nir_deref_type_struct:
 262          assert(deref->type ==
 263                 glsl_get_struct_field(parent->type,
 264                                       nir_deref_as_struct(deref)->elem));
 265          break;
 266
 267       case nir_deref_type_var:
 268          break;
 269
 270       default:
 271          assert(!"Invalid deref type");
 272          break;
 273       }
 274
 275       parent = deref;
 276       deref = deref->child;
 277    }
 278 }
 279
 280 static void
 281 validate_var_use(nir_variable *var, validate_state *state)
 282 {
 283    if (var->data.mode == nir_var_local) {
 284       struct hash_entry *entry = _mesa_hash_table_search(state->var_defs, var);
 285
 286       assert(entry);
 287       assert((nir_function_impl *) entry->data == state->impl);
 288    }
 289 }
 290
 291 static void
 292 validate_deref_var(nir_deref_var *deref, validate_state *state)
 293 {
 294    assert(deref != NULL);
 295    assert(deref->deref.type == deref->var->type);
 296
 297    validate_var_use(deref->var, state);
 298
 299    validate_deref_chain(&deref->deref, state);
 300 }
 301
 302 static void
 303 validate_intrinsic_instr(nir_intrinsic_instr *instr, validate_state *state)
 304 {
 305    unsigned num_srcs = nir_intrinsic_infos[instr->intrinsic].num_srcs;
 306    for (unsigned i = 0; i < num_srcs; i++) {
 307       validate_src(&instr->src[i], state);
 308    }
 309
 310    if (nir_intrinsic_infos[instr->intrinsic].has_dest) {
 311       validate_dest(&instr->dest, state);
 312    }
 313
 314    unsigned num_vars = nir_intrinsic_infos[instr->intrinsic].num_variables;
 315    for (unsigned i = 0; i < num_vars; i++) {
 316       validate_deref_var(instr->variables[i], state);
 317    }
 318
 319    if (instr->has_predicate)
 320       validate_src(&instr->predicate, state);
 321 }
 322
 323 static void
 324 validate_tex_instr(nir_tex_instr *instr, validate_state *state)
 325 {
 326    validate_dest(&instr->dest, state);
 327
 328    bool src_type_seen[nir_num_texinput_types];
 329    for (unsigned i = 0; i < nir_num_texinput_types; i++)
 330       src_type_seen[i] = false;
 331
 332    for (unsigned i = 0; i < instr->num_srcs; i++) {
 333       assert(!src_type_seen[instr->src_type[i]]);
 334       src_type_seen[instr->src_type[i]] = true;
 335       validate_src(&instr->src[i], state);
 336    }
 337
 338    if (instr->sampler != NULL)
 339       validate_deref_var(instr->sampler, state);
 340 }
 341
 342 static void
 343 validate_call_instr(nir_call_instr *instr, validate_state *state)
 344 {
 345    if (instr->return_deref == NULL)
 346       assert(glsl_type_is_void(instr->callee->return_type));
 347    else
 348       assert(instr->return_deref->deref.type == instr->callee->return_type);
 349
 350    assert(instr->num_params == instr->callee->num_params);
 351
 352    for (unsigned i = 0; i < instr->num_params; i++) {
 353       assert(instr->callee->params[i].type == instr->params[i]->deref.type);
 354       validate_deref_var(instr->params[i], state);
 355    }
 356
 357    validate_deref_var(instr->return_deref, state);
 358
 359    if (instr->has_predicate)
 360       validate_src(&instr->predicate, state);
 361 }
 362
 363 static void
 364 validate_load_const_instr(nir_load_const_instr *instr, validate_state *state)
 365 {
 366    validate_dest(&instr->dest, state);
 367
 368    if (instr->array_elems != 0) {
 369       assert(!instr->dest.is_ssa);
 370       assert(instr->dest.reg.base_offset + instr->array_elems <=
 371              instr->dest.reg.reg->num_array_elems);
 372    }
 373
 374    if (instr->has_predicate)
 375       validate_src(&instr->predicate, state);
 376 }
 377
 378 static void
 379 validate_ssa_undef_instr(nir_ssa_undef_instr *instr, validate_state *state)
 380 {
 381    validate_ssa_def(&instr->def, state);
 382 }
 383
 384 static void
 385 validate_phi_instr(nir_phi_instr *instr, validate_state *state)
 386 {
 387    /*
 388     * don't validate the sources until we get to them from their predecessor
 389     * basic blocks, to avoid validating an SSA use before its definition.
 390     */
 391
 392    validate_dest(&instr->dest, state);
 393
 394    exec_list_validate(&instr->srcs);
 395    assert(exec_list_length(&instr->srcs) ==
 396           state->block->predecessors->entries);
 397 }
 398
 399 static void
 400 validate_instr(nir_instr *instr, validate_state *state)
 401 {
 402    assert(instr->block == state->block);
 403
 404    state->instr = instr;
 405
 406    switch (instr->type) {
 407    case nir_instr_type_alu:
 408       validate_alu_instr(nir_instr_as_alu(instr), state);
 409       break;
 410
 411    case nir_instr_type_call:
 412       validate_call_instr(nir_instr_as_call(instr), state);
 413       break;
 414
 415    case nir_instr_type_intrinsic:
 416       validate_intrinsic_instr(nir_instr_as_intrinsic(instr), state);
 417       break;
 418
 419    case nir_instr_type_texture:
 420       validate_tex_instr(nir_instr_as_texture(instr), state);
 421       break;
 422
 423    case nir_instr_type_load_const:
 424       validate_load_const_instr(nir_instr_as_load_const(instr), state);
 425       break;
 426
 427    case nir_instr_type_phi:
 428       validate_phi_instr(nir_instr_as_phi(instr), state);
 429       break;
 430
 431    case nir_instr_type_ssa_undef:
 432       validate_ssa_undef_instr(nir_instr_as_ssa_undef(instr), state);
 433       break;
 434
 435    case nir_instr_type_jump:
 436       break;
 437
 438    default:
 439       assert(!"Invalid ALU instruction type");
 440       break;
 441    }
 442 }
 443
 444 static void
 445 validate_phi_src(nir_phi_instr *instr, nir_block *pred, validate_state *state)
 446 {
 447    state->instr = &instr->instr;
 448
 449    exec_list_validate(&instr->srcs);
 450    foreach_list_typed(nir_phi_src, src, node, &instr->srcs) {
 451       if (src->pred == pred) {
 452          validate_src(&src->src, state);
 453          return;
 454       }
 455    }
 456
 457    abort();
 458 }
 459
 460 static void
 461 validate_phi_srcs(nir_block *block, nir_block *succ, validate_state *state)
 462 {
 463    nir_foreach_instr(succ, instr) {
 464       if (instr->type != nir_instr_type_phi)
 465          break;
 466
 467       validate_phi_src(nir_instr_as_phi(instr), block, state);
 468    }
 469 }
 470
 471 static void validate_cf_node(nir_cf_node *node, validate_state *state);
 472
 473 static void
 474 validate_block(nir_block *block, validate_state *state)
 475 {
 476    assert(block->cf_node.parent == state->parent_node);
 477
 478    state->block = block;
 479
 480    exec_list_validate(&block->instr_list);
 481    nir_foreach_instr(block, instr) {
 482       if (instr->type == nir_instr_type_phi) {
 483          assert(instr == nir_block_first_instr(block) ||
 484                 nir_instr_prev(instr)->type == nir_instr_type_phi);
 485       }
 486
 487       if (instr->type == nir_instr_type_jump) {
 488          assert(instr == nir_block_last_instr(block));
 489       }
 490
 491       validate_instr(instr, state);
 492    }
 493
 494    assert(block->successors[0] != NULL);
 495
 496    for (unsigned i = 0; i < 2; i++) {
 497       if (block->successors[i] != NULL) {
 498          struct set_entry *entry =
 499             _mesa_set_search(block->successors[i]->predecessors,
 500                              _mesa_hash_pointer(block), block);
 501          assert(entry);
 502
 503          validate_phi_srcs(block, block->successors[i], state);
 504       }
 505    }
 506
 507    if (!exec_list_is_empty(&block->instr_list) &&
 508        nir_block_last_instr(block)->type == nir_instr_type_jump)
 509       assert(block->successors[1] == NULL);
 510 }
 511
 512 static void
 513 validate_if(nir_if *if_stmt, validate_state *state)
 514 {
 515    assert(!exec_node_is_head_sentinel(if_stmt->cf_node.node.prev));
 516    nir_cf_node *prev_node = nir_cf_node_prev(&if_stmt->cf_node);
 517    assert(prev_node->type == nir_cf_node_block);
 518
 519    nir_block *prev_block = nir_cf_node_as_block(prev_node);
 520    assert(&prev_block->successors[0]->cf_node ==
 521           nir_if_first_then_node(if_stmt));
 522    assert(&prev_block->successors[1]->cf_node ==
 523           nir_if_first_else_node(if_stmt));
 524
 525    assert(!exec_node_is_tail_sentinel(if_stmt->cf_node.node.next));
 526    nir_cf_node *next_node = nir_cf_node_next(&if_stmt->cf_node);
 527    assert(next_node->type == nir_cf_node_block);
 528
 529    if (!if_stmt->condition.is_ssa) {
 530       nir_register *reg = if_stmt->condition.reg.reg;
 531       struct set_entry *entry =
 532          _mesa_set_search(reg->if_uses, _mesa_hash_pointer(if_stmt), if_stmt);
 533       assert(entry);
 534    } else {
 535       nir_ssa_def *def = if_stmt->condition.ssa;
 536       struct set_entry *entry =
 537          _mesa_set_search(def->if_uses, _mesa_hash_pointer(if_stmt), if_stmt);
 538       assert(entry);
 539    }
 540
 541    assert(!exec_list_is_empty(&if_stmt->then_list));
 542    assert(!exec_list_is_empty(&if_stmt->else_list));
 543
 544    nir_cf_node *old_parent = state->parent_node;
 545    state->parent_node = &if_stmt->cf_node;
 546
 547    exec_list_validate(&if_stmt->then_list);
 548    foreach_list_typed(nir_cf_node, cf_node, node, &if_stmt->then_list) {
 549       validate_cf_node(cf_node, state);
 550    }
 551
 552    exec_list_validate(&if_stmt->else_list);
 553    foreach_list_typed(nir_cf_node, cf_node, node, &if_stmt->else_list) {
 554       validate_cf_node(cf_node, state);
 555    }
 556
 557    state->parent_node = old_parent;
 558 }
 559
 560 static void
 561 validate_loop(nir_loop *loop, validate_state *state)
 562 {
 563    assert(!exec_node_is_head_sentinel(loop->cf_node.node.prev));
 564    nir_cf_node *prev_node = nir_cf_node_prev(&loop->cf_node);
 565    assert(prev_node->type == nir_cf_node_block);
 566
 567    nir_block *prev_block = nir_cf_node_as_block(prev_node);
 568    assert(&prev_block->successors[0]->cf_node == nir_loop_first_cf_node(loop));
 569    assert(prev_block->successors[1] == NULL);
 570
 571    assert(!exec_node_is_tail_sentinel(loop->cf_node.node.next));
 572    nir_cf_node *next_node = nir_cf_node_next(&loop->cf_node);
 573    assert(next_node->type == nir_cf_node_block);
 574
 575    assert(!exec_list_is_empty(&loop->body));
 576
 577    nir_cf_node *old_parent = state->parent_node;
 578    state->parent_node = &loop->cf_node;
 579
 580    exec_list_validate(&loop->body);
 581    foreach_list_typed(nir_cf_node, cf_node, node, &loop->body) {
 582       validate_cf_node(cf_node, state);
 583    }
 584
 585    state->parent_node = old_parent;
 586 }
 587
 588 static void
 589 validate_cf_node(nir_cf_node *node, validate_state *state)
 590 {
 591    assert(node->parent == state->parent_node);
 592
 593    switch (node->type) {
 594    case nir_cf_node_block:
 595       validate_block(nir_cf_node_as_block(node), state);
 596       break;
 597
 598    case nir_cf_node_if:
 599       validate_if(nir_cf_node_as_if(node), state);
 600       break;
 601
 602    case nir_cf_node_loop:
 603       validate_loop(nir_cf_node_as_loop(node), state);
 604       break;
 605
 606    default:
 607       assert(!"Invalid ALU instruction type");
 608       break;
 609    }
 610 }
 611
 612 static void
 613 prevalidate_reg_decl(nir_register *reg, bool is_global, validate_state *state)
 614 {
 615    assert(reg->is_global == is_global);
 616
 617    reg_validate_state *reg_state = ralloc(state->regs, reg_validate_state);
 618    reg_state->uses = _mesa_set_create(reg_state, _mesa_key_pointer_equal);
 619    reg_state->defs = _mesa_set_create(reg_state, _mesa_key_pointer_equal);
 620
 621    reg_state->where_defined = is_global ? NULL : state->impl;
 622
 623    _mesa_hash_table_insert(state->regs, reg, reg_state);
 624 }
 625
 626 static void
 627 postvalidate_reg_decl(nir_register *reg, validate_state *state)
 628 {
 629    struct hash_entry *entry = _mesa_hash_table_search(state->regs, reg);
 630
 631    reg_validate_state *reg_state = (reg_validate_state *) entry->data;
 632
 633    if (reg_state->uses->entries != reg->uses->entries) {
 634       printf("extra entries in register uses:\n");
 635       struct set_entry *entry;
 636       set_foreach(reg->uses, entry) {
 637          struct set_entry *entry2 =
 638             _mesa_set_search(reg_state->uses, _mesa_hash_pointer(entry->key),
 639                              entry->key);
 640
 641          if (entry2 == NULL) {
 642             printf("%p\n", entry->key);
 643          }
 644       }
 645
 646       abort();
 647    }
 648
 649    if (reg_state->defs->entries != reg->defs->entries) {
 650       printf("extra entries in register defs:\n");
 651       struct set_entry *entry;
 652       set_foreach(reg->defs, entry) {
 653          struct set_entry *entry2 =
 654             _mesa_set_search(reg_state->defs, _mesa_hash_pointer(entry->key),
 655                              entry->key);
 656
 657          if (entry2 == NULL) {
 658             printf("%p\n", entry->key);
 659          }
 660       }
 661
 662       abort();
 663    }
 664 }
 665
 666 static void
 667 validate_var_decl(nir_variable *var, bool is_global, validate_state *state)
 668 {
 669    assert(is_global != (var->data.mode == nir_var_local));
 670
 671    /*
 672     * TODO validate some things ir_validate.cpp does (requires more GLSL type
 673     * support)
 674     */
 675
 676    if (!is_global) {
 677       _mesa_hash_table_insert(state->var_defs, var, state->impl);
 678    }
 679 }
 680
 681 static void
 682 validate_function_impl(nir_function_impl *impl, validate_state *state)
 683 {
 684    assert(impl->overload->impl == impl);
 685    assert(impl->cf_node.parent == NULL);
 686
 687    assert(impl->num_params == impl->overload->num_params);
 688    for (unsigned i = 0; i < impl->num_params; i++)
 689       assert(impl->params[i]->type == impl->overload->params[i].type);
 690
 691    if (glsl_type_is_void(impl->overload->return_type))
 692       assert(impl->return_var == NULL);
 693    else
 694       assert(impl->return_var->type == impl->overload->return_type);
 695
 696    assert(exec_list_is_empty(&impl->end_block->instr_list));
 697    assert(impl->end_block->successors[0] == NULL);
 698    assert(impl->end_block->successors[1] == NULL);
 699
 700    state->impl = impl;
 701    state->parent_node = &impl->cf_node;
 702
 703    exec_list_validate(&impl->locals);
 704    foreach_list_typed(nir_variable, var, node, &impl->locals) {
 705       validate_var_decl(var, false, state);
 706    }
 707
 708    exec_list_validate(&impl->registers);
 709    foreach_list_typed(nir_register, reg, node, &impl->registers) {
 710       prevalidate_reg_decl(reg, false, state);
 711    }
 712
 713    exec_list_validate(&impl->body);
 714    foreach_list_typed(nir_cf_node, node, node, &impl->body) {
 715       validate_cf_node(node, state);
 716    }
 717
 718    foreach_list_typed(nir_register, reg, node, &impl->registers) {
 719       postvalidate_reg_decl(reg, state);
 720    }
 721 }
 722
 723 static void
 724 validate_function_overload(nir_function_overload *overload,
 725                            validate_state *state)
 726 {
 727    if (overload->impl != NULL)
 728       validate_function_impl(overload->impl, state);
 729 }
 730
 731 static void
 732 validate_function(nir_function *func, validate_state *state)
 733 {
 734    exec_list_validate(&func->overload_list);
 735    foreach_list_typed(nir_function_overload, overload, node, &func->overload_list) {
 736       assert(overload->function == func);
 737       validate_function_overload(overload, state);
 738    }
 739 }
 740
 741 static void
 742 init_validate_state(validate_state *state)
 743 {
 744    state->regs = _mesa_hash_table_create(NULL, _mesa_hash_pointer,
 745                                          _mesa_key_pointer_equal);
 746    state->ssa_defs = _mesa_hash_table_create(NULL, _mesa_hash_pointer,
 747                                              _mesa_key_pointer_equal);
 748    state->var_defs = _mesa_hash_table_create(NULL, _mesa_hash_pointer,
 749                                              _mesa_key_pointer_equal);
 750 }
 751
 752 static void
 753 destroy_validate_state(validate_state *state)
 754 {
 755    _mesa_hash_table_destroy(state->regs, NULL);
 756    _mesa_hash_table_destroy(state->ssa_defs, NULL);
 757    _mesa_hash_table_destroy(state->var_defs, NULL);
 758 }
 759
 760 void
 761 nir_validate_shader(nir_shader *shader)
 762 {
 763    validate_state state;
 764    init_validate_state(&state);
 765
 766    struct hash_entry *entry;
 767    hash_table_foreach(shader->uniforms, entry) {
 768       validate_var_decl((nir_variable *) entry->data, true, &state);
 769    }
 770
 771    hash_table_foreach(shader->inputs, entry) {
 772      validate_var_decl((nir_variable *) entry->data, true, &state);
 773    }
 774
 775    hash_table_foreach(shader->outputs, entry) {
 776       validate_var_decl((nir_variable *) entry->data, true, &state);
 777    }
 778
 779    exec_list_validate(&shader->globals);
 780    foreach_list_typed(nir_variable, var, node, &shader->globals) {
 781      validate_var_decl(var, true, &state);
 782    }
 783
 784    exec_list_validate(&shader->system_values);
 785    foreach_list_typed(nir_variable, var, node, &shader->system_values) {
 786      validate_var_decl(var, true, &state);
 787    }
 788
 789    exec_list_validate(&shader->registers);
 790    foreach_list_typed(nir_register, reg, node, &shader->registers) {
 791       prevalidate_reg_decl(reg, true, &state);
 792    }
 793
 794    exec_list_validate(&shader->functions);
 795    foreach_list_typed(nir_function, func, node, &shader->functions) {
 796       validate_function(func, &state);
 797    }
 798
 799    foreach_list_typed(nir_register, reg, node, &shader->registers) {
 800       postvalidate_reg_decl(reg, &state);
 801    }
 802
 803    destroy_validate_state(&state);
 804 }