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                   shader_info *si)
  37 {
  38    nir_shader *shader = rzalloc(mem_ctx, nir_shader);
  39
  40    exec_list_make_empty(&shader->uniforms);
  41    exec_list_make_empty(&shader->inputs);
  42    exec_list_make_empty(&shader->outputs);
  43    exec_list_make_empty(&shader->shared);
  44
  45    shader->options = options;
  46
  47    shader->info = si ? si : rzalloc(shader, shader_info);
  48
  49    exec_list_make_empty(&shader->functions);
  50    exec_list_make_empty(&shader->registers);
  51    exec_list_make_empty(&shader->globals);
  52    exec_list_make_empty(&shader->system_values);
  53    shader->reg_alloc = 0;
  54
  55    shader->num_inputs = 0;
  56    shader->num_outputs = 0;
  57    shader->num_uniforms = 0;
  58    shader->num_shared = 0;
  59
  60    shader->stage = stage;
  61
  62    return shader;
  63 }
  64
  65 static nir_register *
  66 reg_create(void *mem_ctx, struct exec_list *list)
  67 {
  68    nir_register *reg = ralloc(mem_ctx, nir_register);
  69
  70    list_inithead(&reg->uses);
  71    list_inithead(&reg->defs);
  72    list_inithead(&reg->if_uses);
  73
  74    reg->num_components = 0;
  75    reg->bit_size = 32;
  76    reg->num_array_elems = 0;
  77    reg->is_packed = false;
  78    reg->name = NULL;
  79
  80    exec_list_push_tail(list, &reg->node);
  81
  82    return reg;
  83 }
  84
  85 nir_register *
  86 nir_global_reg_create(nir_shader *shader)
  87 {
  88    nir_register *reg = reg_create(shader, &shader->registers);
  89    reg->index = shader->reg_alloc++;
  90    reg->is_global = true;
  91
  92    return reg;
  93 }
  94
  95 nir_register *
  96 nir_local_reg_create(nir_function_impl *impl)
  97 {
  98    nir_register *reg = reg_create(ralloc_parent(impl), &impl->registers);
  99    reg->index = impl->reg_alloc++;
 100    reg->is_global = false;
 101
 102    return reg;
 103 }
 104
 105 void
 106 nir_reg_remove(nir_register *reg)
 107 {
 108    exec_node_remove(&reg->node);
 109 }
 110
 111 void
 112 nir_shader_add_variable(nir_shader *shader, nir_variable *var)
 113 {
 114    switch (var->data.mode) {
 115    case nir_var_all:
 116       assert(!"invalid mode");
 117       break;
 118
 119    case nir_var_local:
 120       assert(!"nir_shader_add_variable cannot be used for local variables");
 121       break;
 122
 123    case nir_var_param:
 124       assert(!"nir_shader_add_variable cannot be used for function parameters");
 125       break;
 126
 127    case nir_var_global:
 128       exec_list_push_tail(&shader->globals, &var->node);
 129       break;
 130
 131    case nir_var_shader_in:
 132       exec_list_push_tail(&shader->inputs, &var->node);
 133       break;
 134
 135    case nir_var_shader_out:
 136       exec_list_push_tail(&shader->outputs, &var->node);
 137       break;
 138
 139    case nir_var_uniform:
 140    case nir_var_shader_storage:
 141       exec_list_push_tail(&shader->uniforms, &var->node);
 142       break;
 143
 144    case nir_var_shared:
 145       assert(shader->stage == MESA_SHADER_COMPUTE);
 146       exec_list_push_tail(&shader->shared, &var->node);
 147       break;
 148
 149    case nir_var_system_value:
 150       exec_list_push_tail(&shader->system_values, &var->node);
 151       break;
 152    }
 153 }
 154
 155 nir_variable *
 156 nir_variable_create(nir_shader *shader, nir_variable_mode mode,
 157                     const struct glsl_type *type, const char *name)
 158 {
 159    nir_variable *var = rzalloc(shader, nir_variable);
 160    var->name = ralloc_strdup(var, name);
 161    var->type = type;
 162    var->data.mode = mode;
 163
 164    if ((mode == nir_var_shader_in && shader->stage != MESA_SHADER_VERTEX) ||
 165        (mode == nir_var_shader_out && shader->stage != MESA_SHADER_FRAGMENT))
 166       var->data.interpolation = INTERP_MODE_SMOOTH;
 167
 168    if (mode == nir_var_shader_in || mode == nir_var_uniform)
 169       var->data.read_only = true;
 170
 171    nir_shader_add_variable(shader, var);
 172
 173    return var;
 174 }
 175
 176 nir_variable *
 177 nir_local_variable_create(nir_function_impl *impl,
 178                           const struct glsl_type *type, const char *name)
 179 {
 180    nir_variable *var = rzalloc(impl->function->shader, nir_variable);
 181    var->name = ralloc_strdup(var, name);
 182    var->type = type;
 183    var->data.mode = nir_var_local;
 184
 185    nir_function_impl_add_variable(impl, var);
 186
 187    return var;
 188 }
 189
 190 nir_function *
 191 nir_function_create(nir_shader *shader, const char *name)
 192 {
 193    nir_function *func = ralloc(shader, nir_function);
 194
 195    exec_list_push_tail(&shader->functions, &func->node);
 196
 197    func->name = ralloc_strdup(func, name);
 198    func->shader = shader;
 199    func->num_params = 0;
 200    func->params = NULL;
 201    func->return_type = glsl_void_type();
 202    func->impl = NULL;
 203
 204    return func;
 205 }
 206
 207 void nir_src_copy(nir_src *dest, const nir_src *src, void *mem_ctx)
 208 {
 209    dest->is_ssa = src->is_ssa;
 210    if (src->is_ssa) {
 211       dest->ssa = src->ssa;
 212    } else {
 213       dest->reg.base_offset = src->reg.base_offset;
 214       dest->reg.reg = src->reg.reg;
 215       if (src->reg.indirect) {
 216          dest->reg.indirect = ralloc(mem_ctx, nir_src);
 217          nir_src_copy(dest->reg.indirect, src->reg.indirect, mem_ctx);
 218       } else {
 219          dest->reg.indirect = NULL;
 220       }
 221    }
 222 }
 223
 224 void nir_dest_copy(nir_dest *dest, const nir_dest *src, nir_instr *instr)
 225 {
 226    /* Copying an SSA definition makes no sense whatsoever. */
 227    assert(!src->is_ssa);
 228
 229    dest->is_ssa = false;
 230
 231    dest->reg.base_offset = src->reg.base_offset;
 232    dest->reg.reg = src->reg.reg;
 233    if (src->reg.indirect) {
 234       dest->reg.indirect = ralloc(instr, nir_src);
 235       nir_src_copy(dest->reg.indirect, src->reg.indirect, instr);
 236    } else {
 237       dest->reg.indirect = NULL;
 238    }
 239 }
 240
 241 void
 242 nir_alu_src_copy(nir_alu_src *dest, const nir_alu_src *src,
 243                  nir_alu_instr *instr)
 244 {
 245    nir_src_copy(&dest->src, &src->src, &instr->instr);
 246    dest->abs = src->abs;
 247    dest->negate = src->negate;
 248    for (unsigned i = 0; i < 4; i++)
 249       dest->swizzle[i] = src->swizzle[i];
 250 }
 251
 252 void
 253 nir_alu_dest_copy(nir_alu_dest *dest, const nir_alu_dest *src,
 254                   nir_alu_instr *instr)
 255 {
 256    nir_dest_copy(&dest->dest, &src->dest, &instr->instr);
 257    dest->write_mask = src->write_mask;
 258    dest->saturate = src->saturate;
 259 }
 260
 261
 262 static void
 263 cf_init(nir_cf_node *node, nir_cf_node_type type)
 264 {
 265    exec_node_init(&node->node);
 266    node->parent = NULL;
 267    node->type = type;
 268 }
 269
 270 nir_function_impl *
 271 nir_function_impl_create_bare(nir_shader *shader)
 272 {
 273    nir_function_impl *impl = ralloc(shader, nir_function_impl);
 274
 275    impl->function = NULL;
 276
 277    cf_init(&impl->cf_node, nir_cf_node_function);
 278
 279    exec_list_make_empty(&impl->body);
 280    exec_list_make_empty(&impl->registers);
 281    exec_list_make_empty(&impl->locals);
 282    impl->num_params = 0;
 283    impl->params = NULL;
 284    impl->return_var = NULL;
 285    impl->reg_alloc = 0;
 286    impl->ssa_alloc = 0;
 287    impl->valid_metadata = nir_metadata_none;
 288
 289    /* create start & end blocks */
 290    nir_block *start_block = nir_block_create(shader);
 291    nir_block *end_block = nir_block_create(shader);
 292    start_block->cf_node.parent = &impl->cf_node;
 293    end_block->cf_node.parent = &impl->cf_node;
 294    impl->end_block = end_block;
 295
 296    exec_list_push_tail(&impl->body, &start_block->cf_node.node);
 297
 298    start_block->successors[0] = end_block;
 299    _mesa_set_add(end_block->predecessors, start_block);
 300    return impl;
 301 }
 302
 303 nir_function_impl *
 304 nir_function_impl_create(nir_function *function)
 305 {
 306    assert(function->impl == NULL);
 307
 308    nir_function_impl *impl = nir_function_impl_create_bare(function->shader);
 309
 310    function->impl = impl;
 311    impl->function = function;
 312
 313    impl->num_params = function->num_params;
 314    impl->params = ralloc_array(function->shader,
 315                                nir_variable *, impl->num_params);
 316
 317    for (unsigned i = 0; i < impl->num_params; i++) {
 318       impl->params[i] = rzalloc(function->shader, nir_variable);
 319       impl->params[i]->type = function->params[i].type;
 320       impl->params[i]->data.mode = nir_var_param;
 321       impl->params[i]->data.location = i;
 322    }
 323
 324    if (!glsl_type_is_void(function->return_type)) {
 325       impl->return_var = rzalloc(function->shader, nir_variable);
 326       impl->return_var->type = function->return_type;
 327       impl->return_var->data.mode = nir_var_param;
 328       impl->return_var->data.location = -1;
 329    } else {
 330       impl->return_var = NULL;
 331    }
 332
 333    return impl;
 334 }
 335
 336 nir_block *
 337 nir_block_create(nir_shader *shader)
 338 {
 339    nir_block *block = rzalloc(shader, nir_block);
 340
 341    cf_init(&block->cf_node, nir_cf_node_block);
 342
 343    block->successors[0] = block->successors[1] = NULL;
 344    block->predecessors = _mesa_set_create(block, _mesa_hash_pointer,
 345                                           _mesa_key_pointer_equal);
 346    block->imm_dom = NULL;
 347    /* XXX maybe it would be worth it to defer allocation?  This
 348     * way it doesn't get allocated for shader ref's that never run
 349     * nir_calc_dominance?  For example, state-tracker creates an
 350     * initial IR, clones that, runs appropriate lowering pass, passes
 351     * to driver which does common lowering/opt, and then stores ref
 352     * which is later used to do state specific lowering and futher
 353     * opt.  Do any of the references not need dominance metadata?
 354     */
 355    block->dom_frontier = _mesa_set_create(block, _mesa_hash_pointer,
 356                                           _mesa_key_pointer_equal);
 357
 358    exec_list_make_empty(&block->instr_list);
 359
 360    return block;
 361 }
 362
 363 static inline void
 364 src_init(nir_src *src)
 365 {
 366    src->is_ssa = false;
 367    src->reg.reg = NULL;
 368    src->reg.indirect = NULL;
 369    src->reg.base_offset = 0;
 370 }
 371
 372 nir_if *
 373 nir_if_create(nir_shader *shader)
 374 {
 375    nir_if *if_stmt = ralloc(shader, nir_if);
 376
 377    cf_init(&if_stmt->cf_node, nir_cf_node_if);
 378    src_init(&if_stmt->condition);
 379
 380    nir_block *then = nir_block_create(shader);
 381    exec_list_make_empty(&if_stmt->then_list);
 382    exec_list_push_tail(&if_stmt->then_list, &then->cf_node.node);
 383    then->cf_node.parent = &if_stmt->cf_node;
 384
 385    nir_block *else_stmt = nir_block_create(shader);
 386    exec_list_make_empty(&if_stmt->else_list);
 387    exec_list_push_tail(&if_stmt->else_list, &else_stmt->cf_node.node);
 388    else_stmt->cf_node.parent = &if_stmt->cf_node;
 389
 390    return if_stmt;
 391 }
 392
 393 nir_loop *
 394 nir_loop_create(nir_shader *shader)
 395 {
 396    nir_loop *loop = ralloc(shader, nir_loop);
 397
 398    cf_init(&loop->cf_node, nir_cf_node_loop);
 399
 400    nir_block *body = nir_block_create(shader);
 401    exec_list_make_empty(&loop->body);
 402    exec_list_push_tail(&loop->body, &body->cf_node.node);
 403    body->cf_node.parent = &loop->cf_node;
 404
 405    body->successors[0] = body;
 406    _mesa_set_add(body->predecessors, body);
 407
 408    return loop;
 409 }
 410
 411 static void
 412 instr_init(nir_instr *instr, nir_instr_type type)
 413 {
 414    instr->type = type;
 415    instr->block = NULL;
 416    exec_node_init(&instr->node);
 417 }
 418
 419 static void
 420 dest_init(nir_dest *dest)
 421 {
 422    dest->is_ssa = false;
 423    dest->reg.reg = NULL;
 424    dest->reg.indirect = NULL;
 425    dest->reg.base_offset = 0;
 426 }
 427
 428 static void
 429 alu_dest_init(nir_alu_dest *dest)
 430 {
 431    dest_init(&dest->dest);
 432    dest->saturate = false;
 433    dest->write_mask = 0xf;
 434 }
 435
 436 static void
 437 alu_src_init(nir_alu_src *src)
 438 {
 439    src_init(&src->src);
 440    src->abs = src->negate = false;
 441    src->swizzle[0] = 0;
 442    src->swizzle[1] = 1;
 443    src->swizzle[2] = 2;
 444    src->swizzle[3] = 3;
 445 }
 446
 447 nir_alu_instr *
 448 nir_alu_instr_create(nir_shader *shader, nir_op op)
 449 {
 450    unsigned num_srcs = nir_op_infos[op].num_inputs;
 451    /* TODO: don't use rzalloc */
 452    nir_alu_instr *instr =
 453       rzalloc_size(shader,
 454                    sizeof(nir_alu_instr) + num_srcs * sizeof(nir_alu_src));
 455
 456    instr_init(&instr->instr, nir_instr_type_alu);
 457    instr->op = op;
 458    alu_dest_init(&instr->dest);
 459    for (unsigned i = 0; i < num_srcs; i++)
 460       alu_src_init(&instr->src[i]);
 461
 462    return instr;
 463 }
 464
 465 nir_jump_instr *
 466 nir_jump_instr_create(nir_shader *shader, nir_jump_type type)
 467 {
 468    nir_jump_instr *instr = ralloc(shader, nir_jump_instr);
 469    instr_init(&instr->instr, nir_instr_type_jump);
 470    instr->type = type;
 471    return instr;
 472 }
 473
 474 nir_load_const_instr *
 475 nir_load_const_instr_create(nir_shader *shader, unsigned num_components,
 476                             unsigned bit_size)
 477 {
 478    nir_load_const_instr *instr = ralloc(shader, nir_load_const_instr);
 479    instr_init(&instr->instr, nir_instr_type_load_const);
 480
 481    nir_ssa_def_init(&instr->instr, &instr->def, num_components, bit_size, NULL);
 482
 483    return instr;
 484 }
 485
 486 nir_intrinsic_instr *
 487 nir_intrinsic_instr_create(nir_shader *shader, nir_intrinsic_op op)
 488 {
 489    unsigned num_srcs = nir_intrinsic_infos[op].num_srcs;
 490    /* TODO: don't use rzalloc */
 491    nir_intrinsic_instr *instr =
 492       rzalloc_size(shader,
 493                   sizeof(nir_intrinsic_instr) + num_srcs * sizeof(nir_src));
 494
 495    instr_init(&instr->instr, nir_instr_type_intrinsic);
 496    instr->intrinsic = op;
 497
 498    if (nir_intrinsic_infos[op].has_dest)
 499       dest_init(&instr->dest);
 500
 501    for (unsigned i = 0; i < num_srcs; i++)
 502       src_init(&instr->src[i]);
 503
 504    return instr;
 505 }
 506
 507 nir_call_instr *
 508 nir_call_instr_create(nir_shader *shader, nir_function *callee)
 509 {
 510    nir_call_instr *instr = ralloc(shader, nir_call_instr);
 511    instr_init(&instr->instr, nir_instr_type_call);
 512
 513    instr->callee = callee;
 514    instr->num_params = callee->num_params;
 515    instr->params = ralloc_array(instr, nir_deref_var *, instr->num_params);
 516    instr->return_deref = NULL;
 517
 518    return instr;
 519 }
 520
 521 nir_tex_instr *
 522 nir_tex_instr_create(nir_shader *shader, unsigned num_srcs)
 523 {
 524    nir_tex_instr *instr = rzalloc(shader, nir_tex_instr);
 525    instr_init(&instr->instr, nir_instr_type_tex);
 526
 527    dest_init(&instr->dest);
 528
 529    instr->num_srcs = num_srcs;
 530    instr->src = ralloc_array(instr, nir_tex_src, num_srcs);
 531    for (unsigned i = 0; i < num_srcs; i++)
 532       src_init(&instr->src[i].src);
 533
 534    instr->texture_index = 0;
 535    instr->texture_array_size = 0;
 536    instr->texture = NULL;
 537    instr->sampler_index = 0;
 538    instr->sampler = NULL;
 539
 540    return instr;
 541 }
 542
 543 void
 544 nir_tex_instr_remove_src(nir_tex_instr *tex, unsigned src_idx)
 545 {
 546    assert(src_idx < tex->num_srcs);
 547
 548    /* First rewrite the source to NIR_SRC_INIT */
 549    nir_instr_rewrite_src(&tex->instr, &tex->src[src_idx].src, NIR_SRC_INIT);
 550
 551    /* Now, move all of the other sources down */
 552    for (unsigned i = src_idx + 1; i < tex->num_srcs; i++) {
 553       tex->src[i-1].src_type = tex->src[i].src_type;
 554       nir_instr_move_src(&tex->instr, &tex->src[i-1].src, &tex->src[i].src);
 555    }
 556    tex->num_srcs--;
 557 }
 558
 559 nir_phi_instr *
 560 nir_phi_instr_create(nir_shader *shader)
 561 {
 562    nir_phi_instr *instr = ralloc(shader, nir_phi_instr);
 563    instr_init(&instr->instr, nir_instr_type_phi);
 564
 565    dest_init(&instr->dest);
 566    exec_list_make_empty(&instr->srcs);
 567    return instr;
 568 }
 569
 570 nir_parallel_copy_instr *
 571 nir_parallel_copy_instr_create(nir_shader *shader)
 572 {
 573    nir_parallel_copy_instr *instr = ralloc(shader, nir_parallel_copy_instr);
 574    instr_init(&instr->instr, nir_instr_type_parallel_copy);
 575
 576    exec_list_make_empty(&instr->entries);
 577
 578    return instr;
 579 }
 580
 581 nir_ssa_undef_instr *
 582 nir_ssa_undef_instr_create(nir_shader *shader,
 583                            unsigned num_components,
 584                            unsigned bit_size)
 585 {
 586    nir_ssa_undef_instr *instr = ralloc(shader, nir_ssa_undef_instr);
 587    instr_init(&instr->instr, nir_instr_type_ssa_undef);
 588
 589    nir_ssa_def_init(&instr->instr, &instr->def, num_components, bit_size, NULL);
 590
 591    return instr;
 592 }
 593
 594 nir_deref_var *
 595 nir_deref_var_create(void *mem_ctx, nir_variable *var)
 596 {
 597    nir_deref_var *deref = ralloc(mem_ctx, nir_deref_var);
 598    deref->deref.deref_type = nir_deref_type_var;
 599    deref->deref.child = NULL;
 600    deref->deref.type = var->type;
 601    deref->var = var;
 602    return deref;
 603 }
 604
 605 nir_deref_array *
 606 nir_deref_array_create(void *mem_ctx)
 607 {
 608    nir_deref_array *deref = ralloc(mem_ctx, nir_deref_array);
 609    deref->deref.deref_type = nir_deref_type_array;
 610    deref->deref.child = NULL;
 611    deref->deref_array_type = nir_deref_array_type_direct;
 612    src_init(&deref->indirect);
 613    deref->base_offset = 0;
 614    return deref;
 615 }
 616
 617 nir_deref_struct *
 618 nir_deref_struct_create(void *mem_ctx, unsigned field_index)
 619 {
 620    nir_deref_struct *deref = ralloc(mem_ctx, nir_deref_struct);
 621    deref->deref.deref_type = nir_deref_type_struct;
 622    deref->deref.child = NULL;
 623    deref->index = field_index;
 624    return deref;
 625 }
 626
 627 static nir_deref_var *
 628 copy_deref_var(void *mem_ctx, nir_deref_var *deref)
 629 {
 630    nir_deref_var *ret = nir_deref_var_create(mem_ctx, deref->var);
 631    ret->deref.type = deref->deref.type;
 632    if (deref->deref.child)
 633       ret->deref.child = nir_copy_deref(ret, deref->deref.child);
 634    return ret;
 635 }
 636
 637 static nir_deref_array *
 638 copy_deref_array(void *mem_ctx, nir_deref_array *deref)
 639 {
 640    nir_deref_array *ret = nir_deref_array_create(mem_ctx);
 641    ret->base_offset = deref->base_offset;
 642    ret->deref_array_type = deref->deref_array_type;
 643    if (deref->deref_array_type == nir_deref_array_type_indirect) {
 644       nir_src_copy(&ret->indirect, &deref->indirect, mem_ctx);
 645    }
 646    ret->deref.type = deref->deref.type;
 647    if (deref->deref.child)
 648       ret->deref.child = nir_copy_deref(ret, deref->deref.child);
 649    return ret;
 650 }
 651
 652 static nir_deref_struct *
 653 copy_deref_struct(void *mem_ctx, nir_deref_struct *deref)
 654 {
 655    nir_deref_struct *ret = nir_deref_struct_create(mem_ctx, deref->index);
 656    ret->deref.type = deref->deref.type;
 657    if (deref->deref.child)
 658       ret->deref.child = nir_copy_deref(ret, deref->deref.child);
 659    return ret;
 660 }
 661
 662 nir_deref *
 663 nir_copy_deref(void *mem_ctx, nir_deref *deref)
 664 {
 665    if (deref == NULL)
 666       return NULL;
 667
 668    switch (deref->deref_type) {
 669    case nir_deref_type_var:
 670       return &copy_deref_var(mem_ctx, nir_deref_as_var(deref))->deref;
 671    case nir_deref_type_array:
 672       return &copy_deref_array(mem_ctx, nir_deref_as_array(deref))->deref;
 673    case nir_deref_type_struct:
 674       return &copy_deref_struct(mem_ctx, nir_deref_as_struct(deref))->deref;
 675    default:
 676       unreachable("Invalid dereference type");
 677    }
 678
 679    return NULL;
 680 }
 681
 682 /* This is the second step in the recursion.  We've found the tail and made a
 683  * copy.  Now we need to iterate over all possible leaves and call the
 684  * callback on each one.
 685  */
 686 static bool
 687 deref_foreach_leaf_build_recur(nir_deref_var *deref, nir_deref *tail,
 688                                nir_deref_foreach_leaf_cb cb, void *state)
 689 {
 690    unsigned length;
 691    union {
 692       nir_deref_array arr;
 693       nir_deref_struct str;
 694    } tmp;
 695
 696    assert(tail->child == NULL);
 697    switch (glsl_get_base_type(tail->type)) {
 698    case GLSL_TYPE_UINT:
 699    case GLSL_TYPE_INT:
 700    case GLSL_TYPE_FLOAT:
 701    case GLSL_TYPE_DOUBLE:
 702    case GLSL_TYPE_BOOL:
 703       if (glsl_type_is_vector_or_scalar(tail->type))
 704          return cb(deref, state);
 705       /* Fall Through */
 706
 707    case GLSL_TYPE_ARRAY:
 708       tmp.arr.deref.deref_type = nir_deref_type_array;
 709       tmp.arr.deref.type = glsl_get_array_element(tail->type);
 710       tmp.arr.deref_array_type = nir_deref_array_type_direct;
 711       tmp.arr.indirect = NIR_SRC_INIT;
 712       tail->child = &tmp.arr.deref;
 713
 714       length = glsl_get_length(tail->type);
 715       for (unsigned i = 0; i < length; i++) {
 716          tmp.arr.deref.child = NULL;
 717          tmp.arr.base_offset = i;
 718          if (!deref_foreach_leaf_build_recur(deref, &tmp.arr.deref, cb, state))
 719             return false;
 720       }
 721       return true;
 722
 723    case GLSL_TYPE_STRUCT:
 724       tmp.str.deref.deref_type = nir_deref_type_struct;
 725       tail->child = &tmp.str.deref;
 726
 727       length = glsl_get_length(tail->type);
 728       for (unsigned i = 0; i < length; i++) {
 729          tmp.arr.deref.child = NULL;
 730          tmp.str.deref.type = glsl_get_struct_field(tail->type, i);
 731          tmp.str.index = i;
 732          if (!deref_foreach_leaf_build_recur(deref, &tmp.arr.deref, cb, state))
 733             return false;
 734       }
 735       return true;
 736
 737    default:
 738       unreachable("Invalid type for dereference");
 739    }
 740 }
 741
 742 /* This is the first step of the foreach_leaf recursion.  In this step we are
 743  * walking to the end of the deref chain and making a copy in the stack as we
 744  * go.  This is because we don't want to mutate the deref chain that was
 745  * passed in by the caller.  The downside is that this deref chain is on the
 746  * stack and , if the caller wants to do anything with it, they will have to
 747  * make their own copy because this one will go away.
 748  */
 749 static bool
 750 deref_foreach_leaf_copy_recur(nir_deref_var *deref, nir_deref *tail,
 751                               nir_deref_foreach_leaf_cb cb, void *state)
 752 {
 753    union {
 754       nir_deref_array arr;
 755       nir_deref_struct str;
 756    } c;
 757
 758    if (tail->child) {
 759       switch (tail->child->deref_type) {
 760       case nir_deref_type_array:
 761          c.arr = *nir_deref_as_array(tail->child);
 762          tail->child = &c.arr.deref;
 763          return deref_foreach_leaf_copy_recur(deref, &c.arr.deref, cb, state);
 764
 765       case nir_deref_type_struct:
 766          c.str = *nir_deref_as_struct(tail->child);
 767          tail->child = &c.str.deref;
 768          return deref_foreach_leaf_copy_recur(deref, &c.str.deref, cb, state);
 769
 770       case nir_deref_type_var:
 771       default:
 772          unreachable("Invalid deref type for a child");
 773       }
 774    } else {
 775       /* We've gotten to the end of the original deref.  Time to start
 776        * building our own derefs.
 777        */
 778       return deref_foreach_leaf_build_recur(deref, tail, cb, state);
 779    }
 780 }
 781
 782 /**
 783  * This function iterates over all of the possible derefs that can be created
 784  * with the given deref as the head.  It then calls the provided callback with
 785  * a full deref for each one.
 786  *
 787  * The deref passed to the callback will be allocated on the stack.  You will
 788  * need to make a copy if you want it to hang around.
 789  */
 790 bool
 791 nir_deref_foreach_leaf(nir_deref_var *deref,
 792                        nir_deref_foreach_leaf_cb cb, void *state)
 793 {
 794    nir_deref_var copy = *deref;
 795    return deref_foreach_leaf_copy_recur(&copy, &copy.deref, cb, state);
 796 }
 797
 798 /* Returns a load_const instruction that represents the constant
 799  * initializer for the given deref chain.  The caller is responsible for
 800  * ensuring that there actually is a constant initializer.
 801  */
 802 nir_load_const_instr *
 803 nir_deref_get_const_initializer_load(nir_shader *shader, nir_deref_var *deref)
 804 {
 805    nir_constant *constant = deref->var->constant_initializer;
 806    assert(constant);
 807
 808    const nir_deref *tail = &deref->deref;
 809    unsigned matrix_col = 0;
 810    while (tail->child) {
 811       switch (tail->child->deref_type) {
 812       case nir_deref_type_array: {
 813          nir_deref_array *arr = nir_deref_as_array(tail->child);
 814          assert(arr->deref_array_type == nir_deref_array_type_direct);
 815          if (glsl_type_is_matrix(tail->type)) {
 816             assert(arr->deref.child == NULL);
 817             matrix_col = arr->base_offset;
 818          } else {
 819             constant = constant->elements[arr->base_offset];
 820          }
 821          break;
 822       }
 823
 824       case nir_deref_type_struct: {
 825          constant = constant->elements[nir_deref_as_struct(tail->child)->index];
 826          break;
 827       }
 828
 829       default:
 830          unreachable("Invalid deref child type");
 831       }
 832
 833       tail = tail->child;
 834    }
 835
 836    unsigned bit_size = glsl_get_bit_size(tail->type);
 837    nir_load_const_instr *load =
 838       nir_load_const_instr_create(shader, glsl_get_vector_elements(tail->type),
 839                                   bit_size);
 840
 841    switch (glsl_get_base_type(tail->type)) {
 842    case GLSL_TYPE_FLOAT:
 843    case GLSL_TYPE_INT:
 844    case GLSL_TYPE_UINT:
 845    case GLSL_TYPE_DOUBLE:
 846    case GLSL_TYPE_BOOL:
 847       load->value = constant->values[matrix_col];
 848       break;
 849    default:
 850       unreachable("Invalid immediate type");
 851    }
 852
 853    return load;
 854 }
 855
 856 nir_function_impl *
 857 nir_cf_node_get_function(nir_cf_node *node)
 858 {
 859    while (node->type != nir_cf_node_function) {
 860       node = node->parent;
 861    }
 862
 863    return nir_cf_node_as_function(node);
 864 }
 865
 866 /* Reduces a cursor by trying to convert everything to after and trying to
 867  * go up to block granularity when possible.
 868  */
 869 static nir_cursor
 870 reduce_cursor(nir_cursor cursor)
 871 {
 872    switch (cursor.option) {
 873    case nir_cursor_before_block:
 874       assert(nir_cf_node_prev(&cursor.block->cf_node) == NULL ||
 875              nir_cf_node_prev(&cursor.block->cf_node)->type != nir_cf_node_block);
 876       if (exec_list_is_empty(&cursor.block->instr_list)) {
 877          /* Empty block.  After is as good as before. */
 878          cursor.option = nir_cursor_after_block;
 879       }
 880       return cursor;
 881
 882    case nir_cursor_after_block:
 883       return cursor;
 884
 885    case nir_cursor_before_instr: {
 886       nir_instr *prev_instr = nir_instr_prev(cursor.instr);
 887       if (prev_instr) {
 888          /* Before this instruction is after the previous */
 889          cursor.instr = prev_instr;
 890          cursor.option = nir_cursor_after_instr;
 891       } else {
 892          /* No previous instruction.  Switch to before block */
 893          cursor.block = cursor.instr->block;
 894          cursor.option = nir_cursor_before_block;
 895       }
 896       return reduce_cursor(cursor);
 897    }
 898
 899    case nir_cursor_after_instr:
 900       if (nir_instr_next(cursor.instr) == NULL) {
 901          /* This is the last instruction, switch to after block */
 902          cursor.option = nir_cursor_after_block;
 903          cursor.block = cursor.instr->block;
 904       }
 905       return cursor;
 906
 907    default:
 908       unreachable("Inavlid cursor option");
 909    }
 910 }
 911
 912 bool
 913 nir_cursors_equal(nir_cursor a, nir_cursor b)
 914 {
 915    /* Reduced cursors should be unique */
 916    a = reduce_cursor(a);
 917    b = reduce_cursor(b);
 918
 919    return a.block == b.block && a.option == b.option;
 920 }
 921
 922 static bool
 923 add_use_cb(nir_src *src, void *state)
 924 {
 925    nir_instr *instr = state;
 926
 927    src->parent_instr = instr;
 928    list_addtail(&src->use_link,
 929                 src->is_ssa ? &src->ssa->uses : &src->reg.reg->uses);
 930
 931    return true;
 932 }
 933
 934 static bool
 935 add_ssa_def_cb(nir_ssa_def *def, void *state)
 936 {
 937    nir_instr *instr = state;
 938
 939    if (instr->block && def->index == UINT_MAX) {
 940       nir_function_impl *impl =
 941          nir_cf_node_get_function(&instr->block->cf_node);
 942
 943       def->index = impl->ssa_alloc++;
 944    }
 945
 946    return true;
 947 }
 948
 949 static bool
 950 add_reg_def_cb(nir_dest *dest, void *state)
 951 {
 952    nir_instr *instr = state;
 953
 954    if (!dest->is_ssa) {
 955       dest->reg.parent_instr = instr;
 956       list_addtail(&dest->reg.def_link, &dest->reg.reg->defs);
 957    }
 958
 959    return true;
 960 }
 961
 962 static void
 963 add_defs_uses(nir_instr *instr)
 964 {
 965    nir_foreach_src(instr, add_use_cb, instr);
 966    nir_foreach_dest(instr, add_reg_def_cb, instr);
 967    nir_foreach_ssa_def(instr, add_ssa_def_cb, instr);
 968 }
 969
 970 void
 971 nir_instr_insert(nir_cursor cursor, nir_instr *instr)
 972 {
 973    switch (cursor.option) {
 974    case nir_cursor_before_block:
 975       /* Only allow inserting jumps into empty blocks. */
 976       if (instr->type == nir_instr_type_jump)
 977          assert(exec_list_is_empty(&cursor.block->instr_list));
 978
 979       instr->block = cursor.block;
 980       add_defs_uses(instr);
 981       exec_list_push_head(&cursor.block->instr_list, &instr->node);
 982       break;
 983    case nir_cursor_after_block: {
 984       /* Inserting instructions after a jump is illegal. */
 985       nir_instr *last = nir_block_last_instr(cursor.block);
 986       assert(last == NULL || last->type != nir_instr_type_jump);
 987       (void) last;
 988
 989       instr->block = cursor.block;
 990       add_defs_uses(instr);
 991       exec_list_push_tail(&cursor.block->instr_list, &instr->node);
 992       break;
 993    }
 994    case nir_cursor_before_instr:
 995       assert(instr->type != nir_instr_type_jump);
 996       instr->block = cursor.instr->block;
 997       add_defs_uses(instr);
 998       exec_node_insert_node_before(&cursor.instr->node, &instr->node);
 999       break;
1000    case nir_cursor_after_instr:
1001       /* Inserting instructions after a jump is illegal. */
1002       assert(cursor.instr->type != nir_instr_type_jump);
1003
1004       /* Only allow inserting jumps at the end of the block. */
1005       if (instr->type == nir_instr_type_jump)
1006          assert(cursor.instr == nir_block_last_instr(cursor.instr->block));
1007
1008       instr->block = cursor.instr->block;
1009       add_defs_uses(instr);
1010       exec_node_insert_after(&cursor.instr->node, &instr->node);
1011       break;
1012    }
1013
1014    if (instr->type == nir_instr_type_jump)
1015       nir_handle_add_jump(instr->block);
1016 }
1017
1018 static bool
1019 src_is_valid(const nir_src *src)
1020 {
1021    return src->is_ssa ? (src->ssa != NULL) : (src->reg.reg != NULL);
1022 }
1023
1024 static bool
1025 remove_use_cb(nir_src *src, void *state)
1026 {
1027    (void) state;
1028
1029    if (src_is_valid(src))
1030       list_del(&src->use_link);
1031
1032    return true;
1033 }
1034
1035 static bool
1036 remove_def_cb(nir_dest *dest, void *state)
1037 {
1038    (void) state;
1039
1040    if (!dest->is_ssa)
1041       list_del(&dest->reg.def_link);
1042
1043    return true;
1044 }
1045
1046 static void
1047 remove_defs_uses(nir_instr *instr)
1048 {
1049    nir_foreach_dest(instr, remove_def_cb, instr);
1050    nir_foreach_src(instr, remove_use_cb, instr);
1051 }
1052
1053 void nir_instr_remove(nir_instr *instr)
1054 {
1055    remove_defs_uses(instr);
1056    exec_node_remove(&instr->node);
1057
1058    if (instr->type == nir_instr_type_jump) {
1059       nir_jump_instr *jump_instr = nir_instr_as_jump(instr);
1060       nir_handle_remove_jump(instr->block, jump_instr->type);
1061    }
1062 }
1063
1064 /*@}*/
1065
1066 void
1067 nir_index_local_regs(nir_function_impl *impl)
1068 {
1069    unsigned index = 0;
1070    foreach_list_typed(nir_register, reg, node, &impl->registers) {
1071       reg->index = index++;
1072    }
1073    impl->reg_alloc = index;
1074 }
1075
1076 void
1077 nir_index_global_regs(nir_shader *shader)
1078 {
1079    unsigned index = 0;
1080    foreach_list_typed(nir_register, reg, node, &shader->registers) {
1081       reg->index = index++;
1082    }
1083    shader->reg_alloc = index;
1084 }
1085
1086 static bool
1087 visit_alu_dest(nir_alu_instr *instr, nir_foreach_dest_cb cb, void *state)
1088 {
1089    return cb(&instr->dest.dest, state);
1090 }
1091
1092 static bool
1093 visit_intrinsic_dest(nir_intrinsic_instr *instr, nir_foreach_dest_cb cb,
1094                      void *state)
1095 {
1096    if (nir_intrinsic_infos[instr->intrinsic].has_dest)
1097       return cb(&instr->dest, state);
1098
1099    return true;
1100 }
1101
1102 static bool
1103 visit_texture_dest(nir_tex_instr *instr, nir_foreach_dest_cb cb,
1104                    void *state)
1105 {
1106    return cb(&instr->dest, state);
1107 }
1108
1109 static bool
1110 visit_phi_dest(nir_phi_instr *instr, nir_foreach_dest_cb cb, void *state)
1111 {
1112    return cb(&instr->dest, state);
1113 }
1114
1115 static bool
1116 visit_parallel_copy_dest(nir_parallel_copy_instr *instr,
1117                          nir_foreach_dest_cb cb, void *state)
1118 {
1119    nir_foreach_parallel_copy_entry(entry, instr) {
1120       if (!cb(&entry->dest, state))
1121          return false;
1122    }
1123
1124    return true;
1125 }
1126
1127 bool
1128 nir_foreach_dest(nir_instr *instr, nir_foreach_dest_cb cb, void *state)
1129 {
1130    switch (instr->type) {
1131    case nir_instr_type_alu:
1132       return visit_alu_dest(nir_instr_as_alu(instr), cb, state);
1133    case nir_instr_type_intrinsic:
1134       return visit_intrinsic_dest(nir_instr_as_intrinsic(instr), cb, state);
1135    case nir_instr_type_tex:
1136       return visit_texture_dest(nir_instr_as_tex(instr), cb, state);
1137    case nir_instr_type_phi:
1138       return visit_phi_dest(nir_instr_as_phi(instr), cb, state);
1139    case nir_instr_type_parallel_copy:
1140       return visit_parallel_copy_dest(nir_instr_as_parallel_copy(instr),
1141                                       cb, state);
1142
1143    case nir_instr_type_load_const:
1144    case nir_instr_type_ssa_undef:
1145    case nir_instr_type_call:
1146    case nir_instr_type_jump:
1147       break;
1148
1149    default:
1150       unreachable("Invalid instruction type");
1151       break;
1152    }
1153
1154    return true;
1155 }
1156
1157 struct foreach_ssa_def_state {
1158    nir_foreach_ssa_def_cb cb;
1159    void *client_state;
1160 };
1161
1162 static inline bool
1163 nir_ssa_def_visitor(nir_dest *dest, void *void_state)
1164 {
1165    struct foreach_ssa_def_state *state = void_state;
1166
1167    if (dest->is_ssa)
1168       return state->cb(&dest->ssa, state->client_state);
1169    else
1170       return true;
1171 }
1172
1173 bool
1174 nir_foreach_ssa_def(nir_instr *instr, nir_foreach_ssa_def_cb cb, void *state)
1175 {
1176    switch (instr->type) {
1177    case nir_instr_type_alu:
1178    case nir_instr_type_tex:
1179    case nir_instr_type_intrinsic:
1180    case nir_instr_type_phi:
1181    case nir_instr_type_parallel_copy: {
1182       struct foreach_ssa_def_state foreach_state = {cb, state};
1183       return nir_foreach_dest(instr, nir_ssa_def_visitor, &foreach_state);
1184    }
1185
1186    case nir_instr_type_load_const:
1187       return cb(&nir_instr_as_load_const(instr)->def, state);
1188    case nir_instr_type_ssa_undef:
1189       return cb(&nir_instr_as_ssa_undef(instr)->def, state);
1190    case nir_instr_type_call:
1191    case nir_instr_type_jump:
1192       return true;
1193    default:
1194       unreachable("Invalid instruction type");
1195    }
1196 }
1197
1198 static bool
1199 visit_src(nir_src *src, nir_foreach_src_cb cb, void *state)
1200 {
1201    if (!cb(src, state))
1202       return false;
1203    if (!src->is_ssa && src->reg.indirect)
1204       return cb(src->reg.indirect, state);
1205    return true;
1206 }
1207
1208 static bool
1209 visit_deref_array_src(nir_deref_array *deref, nir_foreach_src_cb cb,
1210                       void *state)
1211 {
1212    if (deref->deref_array_type == nir_deref_array_type_indirect)
1213       return visit_src(&deref->indirect, cb, state);
1214    return true;
1215 }
1216
1217 static bool
1218 visit_deref_src(nir_deref_var *deref, nir_foreach_src_cb cb, void *state)
1219 {
1220    nir_deref *cur = &deref->deref;
1221    while (cur != NULL) {
1222       if (cur->deref_type == nir_deref_type_array) {
1223          if (!visit_deref_array_src(nir_deref_as_array(cur), cb, state))
1224             return false;
1225       }
1226
1227       cur = cur->child;
1228    }
1229
1230    return true;
1231 }
1232
1233 static bool
1234 visit_alu_src(nir_alu_instr *instr, nir_foreach_src_cb cb, void *state)
1235 {
1236    for (unsigned i = 0; i < nir_op_infos[instr->op].num_inputs; i++)
1237       if (!visit_src(&instr->src[i].src, cb, state))
1238          return false;
1239
1240    return true;
1241 }
1242
1243 static bool
1244 visit_tex_src(nir_tex_instr *instr, nir_foreach_src_cb cb, void *state)
1245 {
1246    for (unsigned i = 0; i < instr->num_srcs; i++) {
1247       if (!visit_src(&instr->src[i].src, cb, state))
1248          return false;
1249    }
1250
1251    if (instr->texture != NULL) {
1252       if (!visit_deref_src(instr->texture, cb, state))
1253          return false;
1254    }
1255
1256    if (instr->sampler != NULL) {
1257       if (!visit_deref_src(instr->sampler, cb, state))
1258          return false;
1259    }
1260
1261    return true;
1262 }
1263
1264 static bool
1265 visit_intrinsic_src(nir_intrinsic_instr *instr, nir_foreach_src_cb cb,
1266                     void *state)
1267 {
1268    unsigned num_srcs = nir_intrinsic_infos[instr->intrinsic].num_srcs;
1269    for (unsigned i = 0; i < num_srcs; i++) {
1270       if (!visit_src(&instr->src[i], cb, state))
1271          return false;
1272    }
1273
1274    unsigned num_vars =
1275       nir_intrinsic_infos[instr->intrinsic].num_variables;
1276    for (unsigned i = 0; i < num_vars; i++) {
1277       if (!visit_deref_src(instr->variables[i], cb, state))
1278          return false;
1279    }
1280
1281    return true;
1282 }
1283
1284 static bool
1285 visit_phi_src(nir_phi_instr *instr, nir_foreach_src_cb cb, void *state)
1286 {
1287    nir_foreach_phi_src(src, instr) {
1288       if (!visit_src(&src->src, cb, state))
1289          return false;
1290    }
1291
1292    return true;
1293 }
1294
1295 static bool
1296 visit_parallel_copy_src(nir_parallel_copy_instr *instr,
1297                         nir_foreach_src_cb cb, void *state)
1298 {
1299    nir_foreach_parallel_copy_entry(entry, instr) {
1300       if (!visit_src(&entry->src, cb, state))
1301          return false;
1302    }
1303
1304    return true;
1305 }
1306
1307 typedef struct {
1308    void *state;
1309    nir_foreach_src_cb cb;
1310 } visit_dest_indirect_state;
1311
1312 static bool
1313 visit_dest_indirect(nir_dest *dest, void *_state)
1314 {
1315    visit_dest_indirect_state *state = (visit_dest_indirect_state *) _state;
1316
1317    if (!dest->is_ssa && dest->reg.indirect)
1318       return state->cb(dest->reg.indirect, state->state);
1319
1320    return true;
1321 }
1322
1323 bool
1324 nir_foreach_src(nir_instr *instr, nir_foreach_src_cb cb, void *state)
1325 {
1326    switch (instr->type) {
1327    case nir_instr_type_alu:
1328       if (!visit_alu_src(nir_instr_as_alu(instr), cb, state))
1329          return false;
1330       break;
1331    case nir_instr_type_intrinsic:
1332       if (!visit_intrinsic_src(nir_instr_as_intrinsic(instr), cb, state))
1333          return false;
1334       break;
1335    case nir_instr_type_tex:
1336       if (!visit_tex_src(nir_instr_as_tex(instr), cb, state))
1337          return false;
1338       break;
1339    case nir_instr_type_call:
1340       /* Call instructions have no regular sources */
1341       break;
1342    case nir_instr_type_load_const:
1343       /* Constant load instructions have no regular sources */
1344       break;
1345    case nir_instr_type_phi:
1346       if (!visit_phi_src(nir_instr_as_phi(instr), cb, state))
1347          return false;
1348       break;
1349    case nir_instr_type_parallel_copy:
1350       if (!visit_parallel_copy_src(nir_instr_as_parallel_copy(instr),
1351                                    cb, state))
1352          return false;
1353       break;
1354    case nir_instr_type_jump:
1355    case nir_instr_type_ssa_undef:
1356       return true;
1357
1358    default:
1359       unreachable("Invalid instruction type");
1360       break;
1361    }
1362
1363    visit_dest_indirect_state dest_state;
1364    dest_state.state = state;
1365    dest_state.cb = cb;
1366    return nir_foreach_dest(instr, visit_dest_indirect, &dest_state);
1367 }
1368
1369 nir_const_value *
1370 nir_src_as_const_value(nir_src src)
1371 {
1372    if (!src.is_ssa)
1373       return NULL;
1374
1375    if (src.ssa->parent_instr->type != nir_instr_type_load_const)
1376       return NULL;
1377
1378    nir_load_const_instr *load = nir_instr_as_load_const(src.ssa->parent_instr);
1379
1380    return &load->value;
1381 }
1382
1383 /**
1384  * Returns true if the source is known to be dynamically uniform. Otherwise it
1385  * returns false which means it may or may not be dynamically uniform but it
1386  * can't be determined.
1387  */
1388 bool
1389 nir_src_is_dynamically_uniform(nir_src src)
1390 {
1391    if (!src.is_ssa)
1392       return false;
1393
1394    /* Constants are trivially dynamically uniform */
1395    if (src.ssa->parent_instr->type == nir_instr_type_load_const)
1396       return true;
1397
1398    /* As are uniform variables */
1399    if (src.ssa->parent_instr->type == nir_instr_type_intrinsic) {
1400       nir_intrinsic_instr *intr = nir_instr_as_intrinsic(src.ssa->parent_instr);
1401
1402       if (intr->intrinsic == nir_intrinsic_load_uniform)
1403          return true;
1404    }
1405
1406    /* XXX: this could have many more tests, such as when a sampler function is
1407     * called with dynamically uniform arguments.
1408     */
1409    return false;
1410 }
1411
1412 static void
1413 src_remove_all_uses(nir_src *src)
1414 {
1415    for (; src; src = src->is_ssa ? NULL : src->reg.indirect) {
1416       if (!src_is_valid(src))
1417          continue;
1418
1419       list_del(&src->use_link);
1420    }
1421 }
1422
1423 static void
1424 src_add_all_uses(nir_src *src, nir_instr *parent_instr, nir_if *parent_if)
1425 {
1426    for (; src; src = src->is_ssa ? NULL : src->reg.indirect) {
1427       if (!src_is_valid(src))
1428          continue;
1429
1430       if (parent_instr) {
1431          src->parent_instr = parent_instr;
1432          if (src->is_ssa)
1433             list_addtail(&src->use_link, &src->ssa->uses);
1434          else
1435             list_addtail(&src->use_link, &src->reg.reg->uses);
1436       } else {
1437          assert(parent_if);
1438          src->parent_if = parent_if;
1439          if (src->is_ssa)
1440             list_addtail(&src->use_link, &src->ssa->if_uses);
1441          else
1442             list_addtail(&src->use_link, &src->reg.reg->if_uses);
1443       }
1444    }
1445 }
1446
1447 void
1448 nir_instr_rewrite_src(nir_instr *instr, nir_src *src, nir_src new_src)
1449 {
1450    assert(!src_is_valid(src) || src->parent_instr == instr);
1451
1452    src_remove_all_uses(src);
1453    *src = new_src;
1454    src_add_all_uses(src, instr, NULL);
1455 }
1456
1457 void
1458 nir_instr_move_src(nir_instr *dest_instr, nir_src *dest, nir_src *src)
1459 {
1460    assert(!src_is_valid(dest) || dest->parent_instr == dest_instr);
1461
1462    src_remove_all_uses(dest);
1463    src_remove_all_uses(src);
1464    *dest = *src;
1465    *src = NIR_SRC_INIT;
1466    src_add_all_uses(dest, dest_instr, NULL);
1467 }
1468
1469 void
1470 nir_if_rewrite_condition(nir_if *if_stmt, nir_src new_src)
1471 {
1472    nir_src *src = &if_stmt->condition;
1473    assert(!src_is_valid(src) || src->parent_if == if_stmt);
1474
1475    src_remove_all_uses(src);
1476    *src = new_src;
1477    src_add_all_uses(src, NULL, if_stmt);
1478 }
1479
1480 void
1481 nir_instr_rewrite_dest(nir_instr *instr, nir_dest *dest, nir_dest new_dest)
1482 {
1483    if (dest->is_ssa) {
1484       /* We can only overwrite an SSA destination if it has no uses. */
1485       assert(list_empty(&dest->ssa.uses) && list_empty(&dest->ssa.if_uses));
1486    } else {
1487       list_del(&dest->reg.def_link);
1488       if (dest->reg.indirect)
1489          src_remove_all_uses(dest->reg.indirect);
1490    }
1491
1492    /* We can't re-write with an SSA def */
1493    assert(!new_dest.is_ssa);
1494
1495    nir_dest_copy(dest, &new_dest, instr);
1496
1497    dest->reg.parent_instr = instr;
1498    list_addtail(&dest->reg.def_link, &new_dest.reg.reg->defs);
1499
1500    if (dest->reg.indirect)
1501       src_add_all_uses(dest->reg.indirect, instr, NULL);
1502 }
1503
1504 /* note: does *not* take ownership of 'name' */
1505 void
1506 nir_ssa_def_init(nir_instr *instr, nir_ssa_def *def,
1507                  unsigned num_components,
1508                  unsigned bit_size, const char *name)
1509 {
1510    def->name = ralloc_strdup(instr, name);
1511    def->parent_instr = instr;
1512    list_inithead(&def->uses);
1513    list_inithead(&def->if_uses);
1514    def->num_components = num_components;
1515    def->bit_size = bit_size;
1516
1517    if (instr->block) {
1518       nir_function_impl *impl =
1519          nir_cf_node_get_function(&instr->block->cf_node);
1520
1521       def->index = impl->ssa_alloc++;
1522    } else {
1523       def->index = UINT_MAX;
1524    }
1525 }
1526
1527 /* note: does *not* take ownership of 'name' */
1528 void
1529 nir_ssa_dest_init(nir_instr *instr, nir_dest *dest,
1530                  unsigned num_components, unsigned bit_size,
1531                  const char *name)
1532 {
1533    dest->is_ssa = true;
1534    nir_ssa_def_init(instr, &dest->ssa, num_components, bit_size, name);
1535 }
1536
1537 void
1538 nir_ssa_def_rewrite_uses(nir_ssa_def *def, nir_src new_src)
1539 {
1540    assert(!new_src.is_ssa || def != new_src.ssa);
1541
1542    nir_foreach_use_safe(use_src, def)
1543       nir_instr_rewrite_src(use_src->parent_instr, use_src, new_src);
1544
1545    nir_foreach_if_use_safe(use_src, def)
1546       nir_if_rewrite_condition(use_src->parent_if, new_src);
1547 }
1548
1549 static bool
1550 is_instr_between(nir_instr *start, nir_instr *end, nir_instr *between)
1551 {
1552    assert(start->block == end->block);
1553
1554    if (between->block != start->block)
1555       return false;
1556
1557    /* Search backwards looking for "between" */
1558    while (start != end) {
1559       if (between == end)
1560          return true;
1561
1562       end = nir_instr_prev(end);
1563       assert(end);
1564    }
1565
1566    return false;
1567 }
1568
1569 /* Replaces all uses of the given SSA def with the given source but only if
1570  * the use comes after the after_me instruction.  This can be useful if you
1571  * are emitting code to fix up the result of some instruction: you can freely
1572  * use the result in that code and then call rewrite_uses_after and pass the
1573  * last fixup instruction as after_me and it will replace all of the uses you
1574  * want without touching the fixup code.
1575  *
1576  * This function assumes that after_me is in the same block as
1577  * def->parent_instr and that after_me comes after def->parent_instr.
1578  */
1579 void
1580 nir_ssa_def_rewrite_uses_after(nir_ssa_def *def, nir_src new_src,
1581                                nir_instr *after_me)
1582 {
1583    assert(!new_src.is_ssa || def != new_src.ssa);
1584
1585    nir_foreach_use_safe(use_src, def) {
1586       assert(use_src->parent_instr != def->parent_instr);
1587       /* Since def already dominates all of its uses, the only way a use can
1588        * not be dominated by after_me is if it is between def and after_me in
1589        * the instruction list.
1590        */
1591       if (!is_instr_between(def->parent_instr, after_me, use_src->parent_instr))
1592          nir_instr_rewrite_src(use_src->parent_instr, use_src, new_src);
1593    }
1594
1595    nir_foreach_if_use_safe(use_src, def)
1596       nir_if_rewrite_condition(use_src->parent_if, new_src);
1597 }
1598
1599 uint8_t
1600 nir_ssa_def_components_read(nir_ssa_def *def)
1601 {
1602    uint8_t read_mask = 0;
1603    nir_foreach_use(use, def) {
1604       if (use->parent_instr->type == nir_instr_type_alu) {
1605          nir_alu_instr *alu = nir_instr_as_alu(use->parent_instr);
1606          nir_alu_src *alu_src = exec_node_data(nir_alu_src, use, src);
1607          int src_idx = alu_src - &alu->src[0];
1608          assert(src_idx >= 0 && src_idx < nir_op_infos[alu->op].num_inputs);
1609
1610          for (unsigned c = 0; c < 4; c++) {
1611             if (!nir_alu_instr_channel_used(alu, src_idx, c))
1612                continue;
1613
1614             read_mask |= (1 << alu_src->swizzle[c]);
1615          }
1616       } else {
1617          return (1 << def->num_components) - 1;
1618       }
1619    }
1620
1621    return read_mask;
1622 }
1623
1624 nir_block *
1625 nir_block_cf_tree_next(nir_block *block)
1626 {
1627    if (block == NULL) {
1628       /* nir_foreach_block_safe() will call this function on a NULL block
1629        * after the last iteration, but it won't use the result so just return
1630        * NULL here.
1631        */
1632       return NULL;
1633    }
1634
1635    nir_cf_node *cf_next = nir_cf_node_next(&block->cf_node);
1636    if (cf_next)
1637       return nir_cf_node_cf_tree_first(cf_next);
1638
1639    nir_cf_node *parent = block->cf_node.parent;
1640
1641    switch (parent->type) {
1642    case nir_cf_node_if: {
1643       /* Are we at the end of the if? Go to the beginning of the else */
1644       nir_if *if_stmt = nir_cf_node_as_if(parent);
1645       if (block == nir_if_last_then_block(if_stmt))
1646          return nir_if_first_else_block(if_stmt);
1647
1648       assert(block == nir_if_last_else_block(if_stmt));
1649       /* fall through */
1650    }
1651
1652    case nir_cf_node_loop:
1653       return nir_cf_node_as_block(nir_cf_node_next(parent));
1654
1655    case nir_cf_node_function:
1656       return NULL;
1657
1658    default:
1659       unreachable("unknown cf node type");
1660    }
1661 }
1662
1663 nir_block *
1664 nir_block_cf_tree_prev(nir_block *block)
1665 {
1666    if (block == NULL) {
1667       /* do this for consistency with nir_block_cf_tree_next() */
1668       return NULL;
1669    }
1670
1671    nir_cf_node *cf_prev = nir_cf_node_prev(&block->cf_node);
1672    if (cf_prev)
1673       return nir_cf_node_cf_tree_last(cf_prev);
1674
1675    nir_cf_node *parent = block->cf_node.parent;
1676
1677    switch (parent->type) {
1678    case nir_cf_node_if: {
1679       /* Are we at the beginning of the else? Go to the end of the if */
1680       nir_if *if_stmt = nir_cf_node_as_if(parent);
1681       if (block == nir_if_first_else_block(if_stmt))
1682          return nir_if_last_then_block(if_stmt);
1683
1684       assert(block == nir_if_first_then_block(if_stmt));
1685       /* fall through */
1686    }
1687
1688    case nir_cf_node_loop:
1689       return nir_cf_node_as_block(nir_cf_node_prev(parent));
1690
1691    case nir_cf_node_function:
1692       return NULL;
1693
1694    default:
1695       unreachable("unknown cf node type");
1696    }
1697 }
1698
1699 nir_block *nir_cf_node_cf_tree_first(nir_cf_node *node)
1700 {
1701    switch (node->type) {
1702    case nir_cf_node_function: {
1703       nir_function_impl *impl = nir_cf_node_as_function(node);
1704       return nir_start_block(impl);
1705    }
1706
1707    case nir_cf_node_if: {
1708       nir_if *if_stmt = nir_cf_node_as_if(node);
1709       return nir_if_first_then_block(if_stmt);
1710    }
1711
1712    case nir_cf_node_loop: {
1713       nir_loop *loop = nir_cf_node_as_loop(node);
1714       return nir_loop_first_block(loop);
1715    }
1716
1717    case nir_cf_node_block: {
1718       return nir_cf_node_as_block(node);
1719    }
1720
1721    default:
1722       unreachable("unknown node type");
1723    }
1724 }
1725
1726 nir_block *nir_cf_node_cf_tree_last(nir_cf_node *node)
1727 {
1728    switch (node->type) {
1729    case nir_cf_node_function: {
1730       nir_function_impl *impl = nir_cf_node_as_function(node);
1731       return nir_impl_last_block(impl);
1732    }
1733
1734    case nir_cf_node_if: {
1735       nir_if *if_stmt = nir_cf_node_as_if(node);
1736       return nir_if_last_else_block(if_stmt);
1737    }
1738
1739    case nir_cf_node_loop: {
1740       nir_loop *loop = nir_cf_node_as_loop(node);
1741       return nir_loop_last_block(loop);
1742    }
1743
1744    case nir_cf_node_block: {
1745       return nir_cf_node_as_block(node);
1746    }
1747
1748    default:
1749       unreachable("unknown node type");
1750    }
1751 }
1752
1753 nir_block *nir_cf_node_cf_tree_next(nir_cf_node *node)
1754 {
1755    if (node->type == nir_cf_node_block)
1756       return nir_cf_node_cf_tree_first(nir_cf_node_next(node));
1757    else if (node->type == nir_cf_node_function)
1758       return NULL;
1759    else
1760       return nir_cf_node_as_block(nir_cf_node_next(node));
1761 }
1762
1763 nir_if *
1764 nir_block_get_following_if(nir_block *block)
1765 {
1766    if (exec_node_is_tail_sentinel(&block->cf_node.node))
1767       return NULL;
1768
1769    if (nir_cf_node_is_last(&block->cf_node))
1770       return NULL;
1771
1772    nir_cf_node *next_node = nir_cf_node_next(&block->cf_node);
1773
1774    if (next_node->type != nir_cf_node_if)
1775       return NULL;
1776
1777    return nir_cf_node_as_if(next_node);
1778 }
1779
1780 nir_loop *
1781 nir_block_get_following_loop(nir_block *block)
1782 {
1783    if (exec_node_is_tail_sentinel(&block->cf_node.node))
1784       return NULL;
1785
1786    if (nir_cf_node_is_last(&block->cf_node))
1787       return NULL;
1788
1789    nir_cf_node *next_node = nir_cf_node_next(&block->cf_node);
1790
1791    if (next_node->type != nir_cf_node_loop)
1792       return NULL;
1793
1794    return nir_cf_node_as_loop(next_node);
1795 }
1796
1797 void
1798 nir_index_blocks(nir_function_impl *impl)
1799 {
1800    unsigned index = 0;
1801
1802    if (impl->valid_metadata & nir_metadata_block_index)
1803       return;
1804
1805    nir_foreach_block(block, impl) {
1806       block->index = index++;
1807    }
1808
1809    impl->num_blocks = index;
1810 }
1811
1812 static bool
1813 index_ssa_def_cb(nir_ssa_def *def, void *state)
1814 {
1815    unsigned *index = (unsigned *) state;
1816    def->index = (*index)++;
1817
1818    return true;
1819 }
1820
1821 /**
1822  * The indices are applied top-to-bottom which has the very nice property
1823  * that, if A dominates B, then A->index <= B->index.
1824  */
1825 void
1826 nir_index_ssa_defs(nir_function_impl *impl)
1827 {
1828    unsigned index = 0;
1829
1830    nir_foreach_block(block, impl) {
1831       nir_foreach_instr(instr, block)
1832          nir_foreach_ssa_def(instr, index_ssa_def_cb, &index);
1833    }
1834
1835    impl->ssa_alloc = index;
1836 }
1837
1838 /**
1839  * The indices are applied top-to-bottom which has the very nice property
1840  * that, if A dominates B, then A->index <= B->index.
1841  */
1842 unsigned
1843 nir_index_instrs(nir_function_impl *impl)
1844 {
1845    unsigned index = 0;
1846
1847    nir_foreach_block(block, impl) {
1848       nir_foreach_instr(instr, block)
1849          instr->index = index++;
1850    }
1851
1852    return index;
1853 }
1854
1855 nir_intrinsic_op
1856 nir_intrinsic_from_system_value(gl_system_value val)
1857 {
1858    switch (val) {
1859    case SYSTEM_VALUE_VERTEX_ID:
1860       return nir_intrinsic_load_vertex_id;
1861    case SYSTEM_VALUE_INSTANCE_ID:
1862       return nir_intrinsic_load_instance_id;
1863    case SYSTEM_VALUE_DRAW_ID:
1864       return nir_intrinsic_load_draw_id;
1865    case SYSTEM_VALUE_BASE_INSTANCE:
1866       return nir_intrinsic_load_base_instance;
1867    case SYSTEM_VALUE_VERTEX_ID_ZERO_BASE:
1868       return nir_intrinsic_load_vertex_id_zero_base;
1869    case SYSTEM_VALUE_BASE_VERTEX:
1870       return nir_intrinsic_load_base_vertex;
1871    case SYSTEM_VALUE_INVOCATION_ID:
1872       return nir_intrinsic_load_invocation_id;
1873    case SYSTEM_VALUE_FRONT_FACE:
1874       return nir_intrinsic_load_front_face;
1875    case SYSTEM_VALUE_SAMPLE_ID:
1876       return nir_intrinsic_load_sample_id;
1877    case SYSTEM_VALUE_SAMPLE_POS:
1878       return nir_intrinsic_load_sample_pos;
1879    case SYSTEM_VALUE_SAMPLE_MASK_IN:
1880       return nir_intrinsic_load_sample_mask_in;
1881    case SYSTEM_VALUE_LOCAL_INVOCATION_ID:
1882       return nir_intrinsic_load_local_invocation_id;
1883    case SYSTEM_VALUE_LOCAL_INVOCATION_INDEX:
1884       return nir_intrinsic_load_local_invocation_index;
1885    case SYSTEM_VALUE_WORK_GROUP_ID:
1886       return nir_intrinsic_load_work_group_id;
1887    case SYSTEM_VALUE_NUM_WORK_GROUPS:
1888       return nir_intrinsic_load_num_work_groups;
1889    case SYSTEM_VALUE_PRIMITIVE_ID:
1890       return nir_intrinsic_load_primitive_id;
1891    case SYSTEM_VALUE_TESS_COORD:
1892       return nir_intrinsic_load_tess_coord;
1893    case SYSTEM_VALUE_TESS_LEVEL_OUTER:
1894       return nir_intrinsic_load_tess_level_outer;
1895    case SYSTEM_VALUE_TESS_LEVEL_INNER:
1896       return nir_intrinsic_load_tess_level_inner;
1897    case SYSTEM_VALUE_VERTICES_IN:
1898       return nir_intrinsic_load_patch_vertices_in;
1899    case SYSTEM_VALUE_HELPER_INVOCATION:
1900       return nir_intrinsic_load_helper_invocation;
1901    default:
1902       unreachable("system value does not directly correspond to intrinsic");
1903    }
1904 }
1905
1906 gl_system_value
1907 nir_system_value_from_intrinsic(nir_intrinsic_op intrin)
1908 {
1909    switch (intrin) {
1910    case nir_intrinsic_load_vertex_id:
1911       return SYSTEM_VALUE_VERTEX_ID;
1912    case nir_intrinsic_load_instance_id:
1913       return SYSTEM_VALUE_INSTANCE_ID;
1914    case nir_intrinsic_load_draw_id:
1915       return SYSTEM_VALUE_DRAW_ID;
1916    case nir_intrinsic_load_base_instance:
1917       return SYSTEM_VALUE_BASE_INSTANCE;
1918    case nir_intrinsic_load_vertex_id_zero_base:
1919       return SYSTEM_VALUE_VERTEX_ID_ZERO_BASE;
1920    case nir_intrinsic_load_base_vertex:
1921       return SYSTEM_VALUE_BASE_VERTEX;
1922    case nir_intrinsic_load_invocation_id:
1923       return SYSTEM_VALUE_INVOCATION_ID;
1924    case nir_intrinsic_load_front_face:
1925       return SYSTEM_VALUE_FRONT_FACE;
1926    case nir_intrinsic_load_sample_id:
1927       return SYSTEM_VALUE_SAMPLE_ID;
1928    case nir_intrinsic_load_sample_pos:
1929       return SYSTEM_VALUE_SAMPLE_POS;
1930    case nir_intrinsic_load_sample_mask_in:
1931       return SYSTEM_VALUE_SAMPLE_MASK_IN;
1932    case nir_intrinsic_load_local_invocation_id:
1933       return SYSTEM_VALUE_LOCAL_INVOCATION_ID;
1934    case nir_intrinsic_load_local_invocation_index:
1935       return SYSTEM_VALUE_LOCAL_INVOCATION_INDEX;
1936    case nir_intrinsic_load_num_work_groups:
1937       return SYSTEM_VALUE_NUM_WORK_GROUPS;
1938    case nir_intrinsic_load_work_group_id:
1939       return SYSTEM_VALUE_WORK_GROUP_ID;
1940    case nir_intrinsic_load_primitive_id:
1941       return SYSTEM_VALUE_PRIMITIVE_ID;
1942    case nir_intrinsic_load_tess_coord:
1943       return SYSTEM_VALUE_TESS_COORD;
1944    case nir_intrinsic_load_tess_level_outer:
1945       return SYSTEM_VALUE_TESS_LEVEL_OUTER;
1946    case nir_intrinsic_load_tess_level_inner:
1947       return SYSTEM_VALUE_TESS_LEVEL_INNER;
1948    case nir_intrinsic_load_patch_vertices_in:
1949       return SYSTEM_VALUE_VERTICES_IN;
1950    case nir_intrinsic_load_helper_invocation:
1951       return SYSTEM_VALUE_HELPER_INVOCATION;
1952    default:
1953       unreachable("intrinsic doesn't produce a system value");
1954    }
1955 }