src/glsl/ir_validate.cpp

   1 /*
   2  * Copyright © 2010 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
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 /**
  25  * \file ir_validate.cpp
  26  *
  27  * Attempts to verify that various invariants of the IR tree are true.
  28  *
  29  * In particular, at the moment it makes sure that no single
  30  * ir_instruction node except for ir_variable appears multiple times
  31  * in the ir tree.  ir_variable does appear multiple times: Once as a
  32  * declaration in an exec_list, and multiple times as the endpoint of
  33  * a dereference chain.
  34  */
  35
  36 #include "ir.h"
  37 #include "ir_hierarchical_visitor.h"
  38 #include "program/hash_table.h"
  39 #include "glsl_types.h"
  40
  41 class ir_validate : public ir_hierarchical_visitor {
  42 public:
  43    ir_validate()
  44    {
  45       this->ht = hash_table_ctor(0, hash_table_pointer_hash,
  46                                  hash_table_pointer_compare);
  47
  48       this->current_function = NULL;
  49
  50       this->callback = ir_validate::validate_ir;
  51       this->data = ht;
  52    }
  53
  54    ~ir_validate()
  55    {
  56       hash_table_dtor(this->ht);
  57    }
  58
  59    virtual ir_visitor_status visit(ir_variable *v);
  60    virtual ir_visitor_status visit(ir_dereference_variable *ir);
  61
  62    virtual ir_visitor_status visit_enter(ir_if *ir);
  63
  64    virtual ir_visitor_status visit_leave(ir_loop *ir);
  65    virtual ir_visitor_status visit_enter(ir_function *ir);
  66    virtual ir_visitor_status visit_leave(ir_function *ir);
  67    virtual ir_visitor_status visit_enter(ir_function_signature *ir);
  68
  69    virtual ir_visitor_status visit_leave(ir_expression *ir);
  70    virtual ir_visitor_status visit_leave(ir_swizzle *ir);
  71
  72    virtual ir_visitor_status visit_enter(ir_assignment *ir);
  73    virtual ir_visitor_status visit_enter(ir_call *ir);
  74
  75    static void validate_ir(ir_instruction *ir, void *data);
  76
  77    ir_function *current_function;
  78
  79    struct hash_table *ht;
  80 };
  81
  82
  83 ir_visitor_status
  84 ir_validate::visit(ir_dereference_variable *ir)
  85 {
  86    if ((ir->var == NULL) || (ir->var->as_variable() == NULL)) {
  87       printf("ir_dereference_variable @ %p does not specify a variable %p\n",
  88              (void *) ir, (void *) ir->var);
  89       abort();
  90    }
  91
  92    if (hash_table_find(ht, ir->var) == NULL) {
  93       printf("ir_dereference_variable @ %p specifies undeclared variable "
  94              "`%s' @ %p\n",
  95              (void *) ir, ir->var->name, (void *) ir->var);
  96       abort();
  97    }
  98
  99    this->validate_ir(ir, this->data);
 100
 101    return visit_continue;
 102 }
 103
 104 ir_visitor_status
 105 ir_validate::visit_enter(ir_if *ir)
 106 {
 107    if (ir->condition->type != glsl_type::bool_type) {
 108       printf("ir_if condition %s type instead of bool.\n",
 109              ir->condition->type->name);
 110       ir->print();
 111       printf("\n");
 112       abort();
 113    }
 114
 115    return visit_continue;
 116 }
 117
 118
 119 ir_visitor_status
 120 ir_validate::visit_leave(ir_loop *ir)
 121 {
 122    if (ir->counter != NULL) {
 123       if ((ir->from == NULL) || (ir->from == NULL) || (ir->increment == NULL)) {
 124          printf("ir_loop has invalid loop controls:\n"
 125                 "    counter:   %p\n"
 126                 "    from:      %p\n"
 127                 "    to:        %p\n"
 128                 "    increment: %p\n",
 129                 (void *) ir->counter, (void *) ir->from, (void *) ir->to,
 130                 (void *) ir->increment);
 131          abort();
 132       }
 133
 134       if ((ir->cmp < ir_binop_less) || (ir->cmp > ir_binop_nequal)) {
 135          printf("ir_loop has invalid comparitor %d\n", ir->cmp);
 136          abort();
 137       }
 138    } else {
 139       if ((ir->from != NULL) || (ir->from != NULL) || (ir->increment != NULL)) {
 140          printf("ir_loop has invalid loop controls:\n"
 141                 "    counter:   %p\n"
 142                 "    from:      %p\n"
 143                 "    to:        %p\n"
 144                 "    increment: %p\n",
 145                 (void *) ir->counter, (void *) ir->from, (void *) ir->to,
 146                 (void *) ir->increment);
 147          abort();
 148       }
 149    }
 150
 151    return visit_continue;
 152 }
 153
 154
 155 ir_visitor_status
 156 ir_validate::visit_enter(ir_function *ir)
 157 {
 158    /* Function definitions cannot be nested.
 159     */
 160    if (this->current_function != NULL) {
 161       printf("Function definition nested inside another function "
 162              "definition:\n");
 163       printf("%s %p inside %s %p\n",
 164              ir->name, (void *) ir,
 165              this->current_function->name, (void *) this->current_function);
 166       abort();
 167    }
 168
 169    /* Store the current function hierarchy being traversed.  This is used
 170     * by the function signature visitor to ensure that the signatures are
 171     * linked with the correct functions.
 172     */
 173    this->current_function = ir;
 174
 175    this->validate_ir(ir, this->data);
 176
 177    /* Verify that all of the things stored in the list of signatures are,
 178     * in fact, function signatures.
 179     */
 180    foreach_list(node, &ir->signatures) {
 181       ir_instruction *sig = (ir_instruction *) node;
 182
 183       if (sig->ir_type != ir_type_function_signature) {
 184          printf("Non-signature in signature list of function `%s'\n",
 185                 ir->name);
 186          abort();
 187       }
 188    }
 189
 190    return visit_continue;
 191 }
 192
 193 ir_visitor_status
 194 ir_validate::visit_leave(ir_function *ir)
 195 {
 196    assert(ralloc_parent(ir->name) == ir);
 197
 198    this->current_function = NULL;
 199    return visit_continue;
 200 }
 201
 202 ir_visitor_status
 203 ir_validate::visit_enter(ir_function_signature *ir)
 204 {
 205    if (this->current_function != ir->function()) {
 206       printf("Function signature nested inside wrong function "
 207              "definition:\n");
 208       printf("%p inside %s %p instead of %s %p\n",
 209              (void *) ir,
 210              this->current_function->name, (void *) this->current_function,
 211              ir->function_name(), (void *) ir->function());
 212       abort();
 213    }
 214
 215    if (ir->return_type == NULL) {
 216       printf("Function signature %p for function %s has NULL return type.\n",
 217              (void *) ir, ir->function_name());
 218       abort();
 219    }
 220
 221    this->validate_ir(ir, this->data);
 222
 223    return visit_continue;
 224 }
 225
 226 ir_visitor_status
 227 ir_validate::visit_leave(ir_expression *ir)
 228 {
 229    switch (ir->operation) {
 230    case ir_unop_bit_not:
 231       assert(ir->operands[0]->type == ir->type);
 232       break;
 233    case ir_unop_logic_not:
 234       assert(ir->type->base_type == GLSL_TYPE_BOOL);
 235       assert(ir->operands[0]->type->base_type == GLSL_TYPE_BOOL);
 236       break;
 237
 238    case ir_unop_neg:
 239    case ir_unop_abs:
 240    case ir_unop_sign:
 241    case ir_unop_rcp:
 242    case ir_unop_rsq:
 243    case ir_unop_sqrt:
 244       assert(ir->type == ir->operands[0]->type);
 245       break;
 246
 247    case ir_unop_exp:
 248    case ir_unop_log:
 249    case ir_unop_exp2:
 250    case ir_unop_log2:
 251       assert(ir->operands[0]->type->base_type == GLSL_TYPE_FLOAT);
 252       assert(ir->type == ir->operands[0]->type);
 253       break;
 254
 255    case ir_unop_f2i:
 256       assert(ir->operands[0]->type->base_type == GLSL_TYPE_FLOAT);
 257       assert(ir->type->base_type == GLSL_TYPE_INT);
 258       break;
 259    case ir_unop_i2f:
 260       assert(ir->operands[0]->type->base_type == GLSL_TYPE_INT);
 261       assert(ir->type->base_type == GLSL_TYPE_FLOAT);
 262       break;
 263    case ir_unop_f2b:
 264       assert(ir->operands[0]->type->base_type == GLSL_TYPE_FLOAT);
 265       assert(ir->type->base_type == GLSL_TYPE_BOOL);
 266       break;
 267    case ir_unop_b2f:
 268       assert(ir->operands[0]->type->base_type == GLSL_TYPE_BOOL);
 269       assert(ir->type->base_type == GLSL_TYPE_FLOAT);
 270       break;
 271    case ir_unop_i2b:
 272       assert(ir->operands[0]->type->base_type == GLSL_TYPE_INT);
 273       assert(ir->type->base_type == GLSL_TYPE_BOOL);
 274       break;
 275    case ir_unop_b2i:
 276       assert(ir->operands[0]->type->base_type == GLSL_TYPE_BOOL);
 277       assert(ir->type->base_type == GLSL_TYPE_INT);
 278       break;
 279    case ir_unop_u2f:
 280       assert(ir->operands[0]->type->base_type == GLSL_TYPE_UINT);
 281       assert(ir->type->base_type == GLSL_TYPE_FLOAT);
 282       break;
 283    case ir_unop_i2u:
 284       assert(ir->operands[0]->type->base_type == GLSL_TYPE_INT);
 285       assert(ir->type->base_type == GLSL_TYPE_UINT);
 286       break;
 287    case ir_unop_u2i:
 288       assert(ir->operands[0]->type->base_type == GLSL_TYPE_UINT);
 289       assert(ir->type->base_type == GLSL_TYPE_INT);
 290       break;
 291    case ir_unop_bitcast_i2f:
 292       assert(ir->operands[0]->type->base_type == GLSL_TYPE_INT);
 293       assert(ir->type->base_type == GLSL_TYPE_FLOAT);
 294       break;
 295    case ir_unop_bitcast_f2i:
 296       assert(ir->operands[0]->type->base_type == GLSL_TYPE_FLOAT);
 297       assert(ir->type->base_type == GLSL_TYPE_INT);
 298       break;
 299    case ir_unop_bitcast_u2f:
 300       assert(ir->operands[0]->type->base_type == GLSL_TYPE_UINT);
 301       assert(ir->type->base_type == GLSL_TYPE_FLOAT);
 302       break;
 303    case ir_unop_bitcast_f2u:
 304       assert(ir->operands[0]->type->base_type == GLSL_TYPE_FLOAT);
 305       assert(ir->type->base_type == GLSL_TYPE_UINT);
 306       break;
 307
 308    case ir_unop_any:
 309       assert(ir->operands[0]->type->base_type == GLSL_TYPE_BOOL);
 310       assert(ir->type == glsl_type::bool_type);
 311       break;
 312
 313    case ir_unop_trunc:
 314    case ir_unop_round_even:
 315    case ir_unop_ceil:
 316    case ir_unop_floor:
 317    case ir_unop_fract:
 318    case ir_unop_sin:
 319    case ir_unop_cos:
 320    case ir_unop_sin_reduced:
 321    case ir_unop_cos_reduced:
 322    case ir_unop_dFdx:
 323    case ir_unop_dFdy:
 324       assert(ir->operands[0]->type->base_type == GLSL_TYPE_FLOAT);
 325       assert(ir->operands[0]->type == ir->type);
 326       break;
 327
 328    case ir_unop_noise:
 329       /* XXX what can we assert here? */
 330       break;
 331
 332    case ir_binop_add:
 333    case ir_binop_sub:
 334    case ir_binop_mul:
 335    case ir_binop_div:
 336    case ir_binop_mod:
 337    case ir_binop_min:
 338    case ir_binop_max:
 339    case ir_binop_pow:
 340       if (ir->operands[0]->type->is_scalar())
 341          assert(ir->operands[1]->type == ir->type);
 342       else if (ir->operands[1]->type->is_scalar())
 343          assert(ir->operands[0]->type == ir->type);
 344       else if (ir->operands[0]->type->is_vector() &&
 345                ir->operands[1]->type->is_vector()) {
 346          assert(ir->operands[0]->type == ir->operands[1]->type);
 347          assert(ir->operands[0]->type == ir->type);
 348       }
 349       break;
 350
 351    case ir_binop_less:
 352    case ir_binop_greater:
 353    case ir_binop_lequal:
 354    case ir_binop_gequal:
 355    case ir_binop_equal:
 356    case ir_binop_nequal:
 357       /* The semantics of the IR operators differ from the GLSL <, >, <=, >=,
 358        * ==, and != operators.  The IR operators perform a component-wise
 359        * comparison on scalar or vector types and return a boolean scalar or
 360        * vector type of the same size.
 361        */
 362       assert(ir->type->base_type == GLSL_TYPE_BOOL);
 363       assert(ir->operands[0]->type == ir->operands[1]->type);
 364       assert(ir->operands[0]->type->is_vector()
 365              || ir->operands[0]->type->is_scalar());
 366       assert(ir->operands[0]->type->vector_elements
 367              == ir->type->vector_elements);
 368       break;
 369
 370    case ir_binop_all_equal:
 371    case ir_binop_any_nequal:
 372       /* GLSL == and != operate on scalars, vectors, matrices and arrays, and
 373        * return a scalar boolean.  The IR matches that.
 374        */
 375       assert(ir->type == glsl_type::bool_type);
 376       assert(ir->operands[0]->type == ir->operands[1]->type);
 377       break;
 378
 379    case ir_binop_lshift:
 380    case ir_binop_rshift:
 381       assert(ir->operands[0]->type->is_integer() &&
 382              ir->operands[1]->type->is_integer());
 383       if (ir->operands[0]->type->is_scalar()) {
 384           assert(ir->operands[1]->type->is_scalar());
 385       }
 386       if (ir->operands[0]->type->is_vector() &&
 387           ir->operands[1]->type->is_vector()) {
 388           assert(ir->operands[0]->type->components() ==
 389                  ir->operands[1]->type->components());
 390       }
 391       assert(ir->type == ir->operands[0]->type);
 392       break;
 393
 394    case ir_binop_bit_and:
 395    case ir_binop_bit_xor:
 396    case ir_binop_bit_or:
 397        assert(ir->operands[0]->type->base_type ==
 398               ir->operands[1]->type->base_type);
 399        assert(ir->type->is_integer());
 400        if (ir->operands[0]->type->is_vector() &&
 401            ir->operands[1]->type->is_vector()) {
 402            assert(ir->operands[0]->type->vector_elements ==
 403                   ir->operands[1]->type->vector_elements);
 404        }
 405        break;
 406
 407    case ir_binop_logic_and:
 408    case ir_binop_logic_xor:
 409    case ir_binop_logic_or:
 410       assert(ir->type == glsl_type::bool_type);
 411       assert(ir->operands[0]->type == glsl_type::bool_type);
 412       assert(ir->operands[1]->type == glsl_type::bool_type);
 413       break;
 414
 415    case ir_binop_dot:
 416       assert(ir->type == glsl_type::float_type);
 417       assert(ir->operands[0]->type->base_type == GLSL_TYPE_FLOAT);
 418       assert(ir->operands[0]->type->is_vector());
 419       assert(ir->operands[0]->type == ir->operands[1]->type);
 420       break;
 421
 422    case ir_quadop_vector:
 423       /* The vector operator collects some number of scalars and generates a
 424        * vector from them.
 425        *
 426        *  - All of the operands must be scalar.
 427        *  - Number of operands must matche the size of the resulting vector.
 428        *  - Base type of the operands must match the base type of the result.
 429        */
 430       assert(ir->type->is_vector());
 431       switch (ir->type->vector_elements) {
 432       case 2:
 433          assert(ir->operands[0]->type->is_scalar());
 434          assert(ir->operands[0]->type->base_type == ir->type->base_type);
 435          assert(ir->operands[1]->type->is_scalar());
 436          assert(ir->operands[1]->type->base_type == ir->type->base_type);
 437          assert(ir->operands[2] == NULL);
 438          assert(ir->operands[3] == NULL);
 439          break;
 440       case 3:
 441          assert(ir->operands[0]->type->is_scalar());
 442          assert(ir->operands[0]->type->base_type == ir->type->base_type);
 443          assert(ir->operands[1]->type->is_scalar());
 444          assert(ir->operands[1]->type->base_type == ir->type->base_type);
 445          assert(ir->operands[2]->type->is_scalar());
 446          assert(ir->operands[2]->type->base_type == ir->type->base_type);
 447          assert(ir->operands[3] == NULL);
 448          break;
 449       case 4:
 450          assert(ir->operands[0]->type->is_scalar());
 451          assert(ir->operands[0]->type->base_type == ir->type->base_type);
 452          assert(ir->operands[1]->type->is_scalar());
 453          assert(ir->operands[1]->type->base_type == ir->type->base_type);
 454          assert(ir->operands[2]->type->is_scalar());
 455          assert(ir->operands[2]->type->base_type == ir->type->base_type);
 456          assert(ir->operands[3]->type->is_scalar());
 457          assert(ir->operands[3]->type->base_type == ir->type->base_type);
 458          break;
 459       default:
 460          /* The is_vector assertion above should prevent execution from ever
 461           * getting here.
 462           */
 463          assert(!"Should not get here.");
 464          break;
 465       }
 466    }
 467
 468    return visit_continue;
 469 }
 470
 471 ir_visitor_status
 472 ir_validate::visit_leave(ir_swizzle *ir)
 473 {
 474    unsigned int chans[4] = {ir->mask.x, ir->mask.y, ir->mask.z, ir->mask.w};
 475
 476    for (unsigned int i = 0; i < ir->type->vector_elements; i++) {
 477       if (chans[i] >= ir->val->type->vector_elements) {
 478          printf("ir_swizzle @ %p specifies a channel not present "
 479                 "in the value.\n", (void *) ir);
 480          ir->print();
 481          abort();
 482       }
 483    }
 484
 485    return visit_continue;
 486 }
 487
 488 ir_visitor_status
 489 ir_validate::visit(ir_variable *ir)
 490 {
 491    /* An ir_variable is the one thing that can (and will) appear multiple times
 492     * in an IR tree.  It is added to the hashtable so that it can be used
 493     * in the ir_dereference_variable handler to ensure that a variable is
 494     * declared before it is dereferenced.
 495     */
 496    if (ir->name)
 497       assert(ralloc_parent(ir->name) == ir);
 498
 499    hash_table_insert(ht, ir, ir);
 500
 501
 502    /* If a variable is an array, verify that the maximum array index is in
 503     * bounds.  There was once an error in AST-to-HIR conversion that set this
 504     * to be out of bounds.
 505     */
 506    if (ir->type->array_size() > 0) {
 507       if (ir->max_array_access >= ir->type->length) {
 508          printf("ir_variable has maximum access out of bounds (%d vs %d)\n",
 509                 ir->max_array_access, ir->type->length - 1);
 510          ir->print();
 511          abort();
 512       }
 513    }
 514
 515    if (ir->constant_initializer != NULL && !ir->has_initializer) {
 516       printf("ir_variable didn't have an initializer, but has a constant "
 517              "initializer value.\n");
 518       ir->print();
 519       abort();
 520    }
 521
 522    return visit_continue;
 523 }
 524
 525 ir_visitor_status
 526 ir_validate::visit_enter(ir_assignment *ir)
 527 {
 528    const ir_dereference *const lhs = ir->lhs;
 529    if (lhs->type->is_scalar() || lhs->type->is_vector()) {
 530       if (ir->write_mask == 0) {
 531          printf("Assignment LHS is %s, but write mask is 0:\n",
 532                 lhs->type->is_scalar() ? "scalar" : "vector");
 533          ir->print();
 534          abort();
 535       }
 536
 537       int lhs_components = 0;
 538       for (int i = 0; i < 4; i++) {
 539          if (ir->write_mask & (1 << i))
 540             lhs_components++;
 541       }
 542
 543       if (lhs_components != ir->rhs->type->vector_elements) {
 544          printf("Assignment count of LHS write mask channels enabled not\n"
 545                 "matching RHS vector size (%d LHS, %d RHS).\n",
 546                 lhs_components, ir->rhs->type->vector_elements);
 547          ir->print();
 548          abort();
 549       }
 550    }
 551
 552    this->validate_ir(ir, this->data);
 553
 554    return visit_continue;
 555 }
 556
 557 ir_visitor_status
 558 ir_validate::visit_enter(ir_call *ir)
 559 {
 560    ir_function_signature *const callee = ir->callee;
 561
 562    if (callee->ir_type != ir_type_function_signature) {
 563       printf("IR called by ir_call is not ir_function_signature!\n");
 564       abort();
 565    }
 566
 567    if (ir->return_deref) {
 568       if (ir->return_deref->type != callee->return_type) {
 569          printf("callee type %s does not match return storage type %s\n",
 570                 callee->return_type->name, ir->return_deref->type->name);
 571          abort();
 572       }
 573    } else if (callee->return_type != glsl_type::void_type) {
 574       printf("ir_call has non-void callee but no return storage\n");
 575       abort();
 576    }
 577
 578    const exec_node *formal_param_node = callee->parameters.head;
 579    const exec_node *actual_param_node = ir->actual_parameters.head;
 580    while (true) {
 581       if (formal_param_node->is_tail_sentinel()
 582           != actual_param_node->is_tail_sentinel()) {
 583          printf("ir_call has the wrong number of parameters:\n");
 584          goto dump_ir;
 585       }
 586       if (formal_param_node->is_tail_sentinel()) {
 587          break;
 588       }
 589       const ir_variable *formal_param
 590          = (const ir_variable *) formal_param_node;
 591       const ir_rvalue *actual_param
 592          = (const ir_rvalue *) actual_param_node;
 593       if (formal_param->type != actual_param->type) {
 594          printf("ir_call parameter type mismatch:\n");
 595          goto dump_ir;
 596       }
 597       if (formal_param->mode == ir_var_out
 598           || formal_param->mode == ir_var_inout) {
 599          if (!actual_param->is_lvalue()) {
 600             printf("ir_call out/inout parameters must be lvalues:\n");
 601             goto dump_ir;
 602          }
 603       }
 604       formal_param_node = formal_param_node->next;
 605       actual_param_node = actual_param_node->next;
 606    }
 607
 608    return visit_continue;
 609
 610 dump_ir:
 611    ir->print();
 612    printf("callee:\n");
 613    callee->print();
 614    abort();
 615    return visit_stop;
 616 }
 617
 618 void
 619 ir_validate::validate_ir(ir_instruction *ir, void *data)
 620 {
 621    struct hash_table *ht = (struct hash_table *) data;
 622
 623    if (hash_table_find(ht, ir)) {
 624       printf("Instruction node present twice in ir tree:\n");
 625       ir->print();
 626       printf("\n");
 627       abort();
 628    }
 629    hash_table_insert(ht, ir, ir);
 630 }
 631
 632 void
 633 check_node_type(ir_instruction *ir, void *data)
 634 {
 635    (void) data;
 636
 637    if (ir->ir_type <= ir_type_unset || ir->ir_type >= ir_type_max) {
 638       printf("Instruction node with unset type\n");
 639       ir->print(); printf("\n");
 640    }
 641    ir_rvalue *value = ir->as_rvalue();
 642    if (value != NULL)
 643       assert(value->type != glsl_type::error_type);
 644 }
 645
 646 void
 647 validate_ir_tree(exec_list *instructions)
 648 {
 649    ir_validate v;
 650
 651    v.run(instructions);
 652
 653    foreach_iter(exec_list_iterator, iter, *instructions) {
 654       ir_instruction *ir = (ir_instruction *)iter.get();
 655
 656       visit_tree(ir, check_node_type, NULL);
 657    }
 658 }