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 = rzalloc(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 nir_deref_var *
 628 nir_deref_var_clone(const nir_deref_var *deref, void *mem_ctx)
 629 {
 630    if (deref == NULL)
 631       return NULL;
 632
 633    nir_deref_var *ret = nir_deref_var_create(mem_ctx, deref->var);
 634    ret->deref.type = deref->deref.type;
 635    if (deref->deref.child)
 636       ret->deref.child = nir_deref_clone(deref->deref.child, ret);
 637    return ret;
 638 }
 639
 640 static nir_deref_array *
 641 deref_array_clone(const nir_deref_array *deref, void *mem_ctx)
 642 {
 643    nir_deref_array *ret = nir_deref_array_create(mem_ctx);
 644    ret->base_offset = deref->base_offset;
 645    ret->deref_array_type = deref->deref_array_type;
 646    if (deref->deref_array_type == nir_deref_array_type_indirect) {
 647       nir_src_copy(&ret->indirect, &deref->indirect, mem_ctx);
 648    }
 649    ret->deref.type = deref->deref.type;
 650    if (deref->deref.child)
 651       ret->deref.child = nir_deref_clone(deref->deref.child, ret);
 652    return ret;
 653 }
 654
 655 static nir_deref_struct *
 656 deref_struct_clone(const nir_deref_struct *deref, void *mem_ctx)
 657 {
 658    nir_deref_struct *ret = nir_deref_struct_create(mem_ctx, deref->index);
 659    ret->deref.type = deref->deref.type;
 660    if (deref->deref.child)
 661       ret->deref.child = nir_deref_clone(deref->deref.child, ret);
 662    return ret;
 663 }
 664
 665 nir_deref *
 666 nir_deref_clone(const nir_deref *deref, void *mem_ctx)
 667 {
 668    if (deref == NULL)
 669       return NULL;
 670
 671    switch (deref->deref_type) {
 672    case nir_deref_type_var:
 673       return &nir_deref_var_clone(nir_deref_as_var(deref), mem_ctx)->deref;
 674    case nir_deref_type_array:
 675       return &deref_array_clone(nir_deref_as_array(deref), mem_ctx)->deref;
 676    case nir_deref_type_struct:
 677       return &deref_struct_clone(nir_deref_as_struct(deref), mem_ctx)->deref;
 678    default:
 679       unreachable("Invalid dereference type");
 680    }
 681
 682    return NULL;
 683 }
 684
 685 /* This is the second step in the recursion.  We've found the tail and made a
 686  * copy.  Now we need to iterate over all possible leaves and call the
 687  * callback on each one.
 688  */
 689 static bool
 690 deref_foreach_leaf_build_recur(nir_deref_var *deref, nir_deref *tail,
 691                                nir_deref_foreach_leaf_cb cb, void *state)
 692 {
 693    unsigned length;
 694    union {
 695       nir_deref_array arr;
 696       nir_deref_struct str;
 697    } tmp;
 698
 699    assert(tail->child == NULL);
 700    switch (glsl_get_base_type(tail->type)) {
 701    case GLSL_TYPE_UINT:
 702    case GLSL_TYPE_INT:
 703    case GLSL_TYPE_FLOAT:
 704    case GLSL_TYPE_DOUBLE:
 705    case GLSL_TYPE_BOOL:
 706       if (glsl_type_is_vector_or_scalar(tail->type))
 707          return cb(deref, state);
 708       /* Fall Through */
 709
 710    case GLSL_TYPE_ARRAY:
 711       tmp.arr.deref.deref_type = nir_deref_type_array;
 712       tmp.arr.deref.type = glsl_get_array_element(tail->type);
 713       tmp.arr.deref_array_type = nir_deref_array_type_direct;
 714       tmp.arr.indirect = NIR_SRC_INIT;
 715       tail->child = &tmp.arr.deref;
 716
 717       length = glsl_get_length(tail->type);
 718       for (unsigned i = 0; i < length; i++) {
 719          tmp.arr.deref.child = NULL;
 720          tmp.arr.base_offset = i;
 721          if (!deref_foreach_leaf_build_recur(deref, &tmp.arr.deref, cb, state))
 722             return false;
 723       }
 724       return true;
 725
 726    case GLSL_TYPE_STRUCT:
 727       tmp.str.deref.deref_type = nir_deref_type_struct;
 728       tail->child = &tmp.str.deref;
 729
 730       length = glsl_get_length(tail->type);
 731       for (unsigned i = 0; i < length; i++) {
 732          tmp.arr.deref.child = NULL;
 733          tmp.str.deref.type = glsl_get_struct_field(tail->type, i);
 734          tmp.str.index = i;
 735          if (!deref_foreach_leaf_build_recur(deref, &tmp.arr.deref, cb, state))
 736             return false;
 737       }
 738       return true;
 739
 740    default:
 741       unreachable("Invalid type for dereference");
 742    }
 743 }
 744
 745 /* This is the first step of the foreach_leaf recursion.  In this step we are
 746  * walking to the end of the deref chain and making a copy in the stack as we
 747  * go.  This is because we don't want to mutate the deref chain that was
 748  * passed in by the caller.  The downside is that this deref chain is on the
 749  * stack and , if the caller wants to do anything with it, they will have to
 750  * make their own copy because this one will go away.
 751  */
 752 static bool
 753 deref_foreach_leaf_copy_recur(nir_deref_var *deref, nir_deref *tail,
 754                               nir_deref_foreach_leaf_cb cb, void *state)
 755 {
 756    union {
 757       nir_deref_array arr;
 758       nir_deref_struct str;
 759    } c;
 760
 761    if (tail->child) {
 762       switch (tail->child->deref_type) {
 763       case nir_deref_type_array:
 764          c.arr = *nir_deref_as_array(tail->child);
 765          tail->child = &c.arr.deref;
 766          return deref_foreach_leaf_copy_recur(deref, &c.arr.deref, cb, state);
 767
 768       case nir_deref_type_struct:
 769          c.str = *nir_deref_as_struct(tail->child);
 770          tail->child = &c.str.deref;
 771          return deref_foreach_leaf_copy_recur(deref, &c.str.deref, cb, state);
 772
 773       case nir_deref_type_var:
 774       default:
 775          unreachable("Invalid deref type for a child");
 776       }
 777    } else {
 778       /* We've gotten to the end of the original deref.  Time to start
 779        * building our own derefs.
 780        */
 781       return deref_foreach_leaf_build_recur(deref, tail, cb, state);
 782    }
 783 }
 784
 785 /**
 786  * This function iterates over all of the possible derefs that can be created
 787  * with the given deref as the head.  It then calls the provided callback with
 788  * a full deref for each one.
 789  *
 790  * The deref passed to the callback will be allocated on the stack.  You will
 791  * need to make a copy if you want it to hang around.
 792  */
 793 bool
 794 nir_deref_foreach_leaf(nir_deref_var *deref,
 795                        nir_deref_foreach_leaf_cb cb, void *state)
 796 {
 797    nir_deref_var copy = *deref;
 798    return deref_foreach_leaf_copy_recur(&copy, &copy.deref, cb, state);
 799 }
 800
 801 /* Returns a load_const instruction that represents the constant
 802  * initializer for the given deref chain.  The caller is responsible for
 803  * ensuring that there actually is a constant initializer.
 804  */
 805 nir_load_const_instr *
 806 nir_deref_get_const_initializer_load(nir_shader *shader, nir_deref_var *deref)
 807 {
 808    nir_constant *constant = deref->var->constant_initializer;
 809    assert(constant);
 810
 811    const nir_deref *tail = &deref->deref;
 812    unsigned matrix_col = 0;
 813    while (tail->child) {
 814       switch (tail->child->deref_type) {
 815       case nir_deref_type_array: {
 816          nir_deref_array *arr = nir_deref_as_array(tail->child);
 817          assert(arr->deref_array_type == nir_deref_array_type_direct);
 818          if (glsl_type_is_matrix(tail->type)) {
 819             assert(arr->deref.child == NULL);
 820             matrix_col = arr->base_offset;
 821          } else {
 822             constant = constant->elements[arr->base_offset];
 823          }
 824          break;
 825       }
 826
 827       case nir_deref_type_struct: {
 828          constant = constant->elements[nir_deref_as_struct(tail->child)->index];
 829          break;
 830       }
 831
 832       default:
 833          unreachable("Invalid deref child type");
 834       }
 835
 836       tail = tail->child;
 837    }
 838
 839    unsigned bit_size = glsl_get_bit_size(tail->type);
 840    nir_load_const_instr *load =
 841       nir_load_const_instr_create(shader, glsl_get_vector_elements(tail->type),
 842                                   bit_size);
 843
 844    switch (glsl_get_base_type(tail->type)) {
 845    case GLSL_TYPE_FLOAT:
 846    case GLSL_TYPE_INT:
 847    case GLSL_TYPE_UINT:
 848    case GLSL_TYPE_DOUBLE:
 849    case GLSL_TYPE_BOOL:
 850       load->value = constant->values[matrix_col];
 851       break;
 852    default:
 853       unreachable("Invalid immediate type");
 854    }
 855
 856    return load;
 857 }
 858
 859 nir_function_impl *
 860 nir_cf_node_get_function(nir_cf_node *node)
 861 {
 862    while (node->type != nir_cf_node_function) {
 863       node = node->parent;
 864    }
 865
 866    return nir_cf_node_as_function(node);
 867 }
 868
 869 /* Reduces a cursor by trying to convert everything to after and trying to
 870  * go up to block granularity when possible.
 871  */
 872 static nir_cursor
 873 reduce_cursor(nir_cursor cursor)
 874 {
 875    switch (cursor.option) {
 876    case nir_cursor_before_block:
 877       assert(nir_cf_node_prev(&cursor.block->cf_node) == NULL ||
 878              nir_cf_node_prev(&cursor.block->cf_node)->type != nir_cf_node_block);
 879       if (exec_list_is_empty(&cursor.block->instr_list)) {
 880          /* Empty block.  After is as good as before. */
 881          cursor.option = nir_cursor_after_block;
 882       }
 883       return cursor;
 884
 885    case nir_cursor_after_block:
 886       return cursor;
 887
 888    case nir_cursor_before_instr: {
 889       nir_instr *prev_instr = nir_instr_prev(cursor.instr);
 890       if (prev_instr) {
 891          /* Before this instruction is after the previous */
 892          cursor.instr = prev_instr;
 893          cursor.option = nir_cursor_after_instr;
 894       } else {
 895          /* No previous instruction.  Switch to before block */
 896          cursor.block = cursor.instr->block;
 897          cursor.option = nir_cursor_before_block;
 898       }
 899       return reduce_cursor(cursor);
 900    }
 901
 902    case nir_cursor_after_instr:
 903       if (nir_instr_next(cursor.instr) == NULL) {
 904          /* This is the last instruction, switch to after block */
 905          cursor.option = nir_cursor_after_block;
 906          cursor.block = cursor.instr->block;
 907       }
 908       return cursor;
 909
 910    default:
 911       unreachable("Inavlid cursor option");
 912    }
 913 }
 914
 915 bool
 916 nir_cursors_equal(nir_cursor a, nir_cursor b)
 917 {
 918    /* Reduced cursors should be unique */
 919    a = reduce_cursor(a);
 920    b = reduce_cursor(b);
 921
 922    return a.block == b.block && a.option == b.option;
 923 }
 924
 925 static bool
 926 add_use_cb(nir_src *src, void *state)
 927 {
 928    nir_instr *instr = state;
 929
 930    src->parent_instr = instr;
 931    list_addtail(&src->use_link,
 932                 src->is_ssa ? &src->ssa->uses : &src->reg.reg->uses);
 933
 934    return true;
 935 }
 936
 937 static bool
 938 add_ssa_def_cb(nir_ssa_def *def, void *state)
 939 {
 940    nir_instr *instr = state;
 941
 942    if (instr->block && def->index == UINT_MAX) {
 943       nir_function_impl *impl =
 944          nir_cf_node_get_function(&instr->block->cf_node);
 945
 946       def->index = impl->ssa_alloc++;
 947    }
 948
 949    return true;
 950 }
 951
 952 static bool
 953 add_reg_def_cb(nir_dest *dest, void *state)
 954 {
 955    nir_instr *instr = state;
 956
 957    if (!dest->is_ssa) {
 958       dest->reg.parent_instr = instr;
 959       list_addtail(&dest->reg.def_link, &dest->reg.reg->defs);
 960    }
 961
 962    return true;
 963 }
 964
 965 static void
 966 add_defs_uses(nir_instr *instr)
 967 {
 968    nir_foreach_src(instr, add_use_cb, instr);
 969    nir_foreach_dest(instr, add_reg_def_cb, instr);
 970    nir_foreach_ssa_def(instr, add_ssa_def_cb, instr);
 971 }
 972
 973 void
 974 nir_instr_insert(nir_cursor cursor, nir_instr *instr)
 975 {
 976    switch (cursor.option) {
 977    case nir_cursor_before_block:
 978       /* Only allow inserting jumps into empty blocks. */
 979       if (instr->type == nir_instr_type_jump)
 980          assert(exec_list_is_empty(&cursor.block->instr_list));
 981
 982       instr->block = cursor.block;
 983       add_defs_uses(instr);
 984       exec_list_push_head(&cursor.block->instr_list, &instr->node);
 985       break;
 986    case nir_cursor_after_block: {
 987       /* Inserting instructions after a jump is illegal. */
 988       nir_instr *last = nir_block_last_instr(cursor.block);
 989       assert(last == NULL || last->type != nir_instr_type_jump);
 990       (void) last;
 991
 992       instr->block = cursor.block;
 993       add_defs_uses(instr);
 994       exec_list_push_tail(&cursor.block->instr_list, &instr->node);
 995       break;
 996    }
 997    case nir_cursor_before_instr:
 998       assert(instr->type != nir_instr_type_jump);
 999       instr->block = cursor.instr->block;
1000       add_defs_uses(instr);
1001       exec_node_insert_node_before(&cursor.instr->node, &instr->node);
1002       break;
1003    case nir_cursor_after_instr:
1004       /* Inserting instructions after a jump is illegal. */
1005       assert(cursor.instr->type != nir_instr_type_jump);
1006
1007       /* Only allow inserting jumps at the end of the block. */
1008       if (instr->type == nir_instr_type_jump)
1009          assert(cursor.instr == nir_block_last_instr(cursor.instr->block));
1010
1011       instr->block = cursor.instr->block;
1012       add_defs_uses(instr);
1013       exec_node_insert_after(&cursor.instr->node, &instr->node);
1014       break;
1015    }
1016
1017    if (instr->type == nir_instr_type_jump)
1018       nir_handle_add_jump(instr->block);
1019 }
1020
1021 static bool
1022 src_is_valid(const nir_src *src)
1023 {
1024    return src->is_ssa ? (src->ssa != NULL) : (src->reg.reg != NULL);
1025 }
1026
1027 static bool
1028 remove_use_cb(nir_src *src, void *state)
1029 {
1030    (void) state;
1031
1032    if (src_is_valid(src))
1033       list_del(&src->use_link);
1034
1035    return true;
1036 }
1037
1038 static bool
1039 remove_def_cb(nir_dest *dest, void *state)
1040 {
1041    (void) state;
1042
1043    if (!dest->is_ssa)
1044       list_del(&dest->reg.def_link);
1045
1046    return true;
1047 }
1048
1049 static void
1050 remove_defs_uses(nir_instr *instr)
1051 {
1052    nir_foreach_dest(instr, remove_def_cb, instr);
1053    nir_foreach_src(instr, remove_use_cb, instr);
1054 }
1055
1056 void nir_instr_remove(nir_instr *instr)
1057 {
1058    remove_defs_uses(instr);
1059    exec_node_remove(&instr->node);
1060
1061    if (instr->type == nir_instr_type_jump) {
1062       nir_jump_instr *jump_instr = nir_instr_as_jump(instr);
1063       nir_handle_remove_jump(instr->block, jump_instr->type);
1064    }
1065 }
1066
1067 /*@}*/
1068
1069 void
1070 nir_index_local_regs(nir_function_impl *impl)
1071 {
1072    unsigned index = 0;
1073    foreach_list_typed(nir_register, reg, node, &impl->registers) {
1074       reg->index = index++;
1075    }
1076    impl->reg_alloc = index;
1077 }
1078
1079 void
1080 nir_index_global_regs(nir_shader *shader)
1081 {
1082    unsigned index = 0;
1083    foreach_list_typed(nir_register, reg, node, &shader->registers) {
1084       reg->index = index++;
1085    }
1086    shader->reg_alloc = index;
1087 }
1088
1089 static bool
1090 visit_alu_dest(nir_alu_instr *instr, nir_foreach_dest_cb cb, void *state)
1091 {
1092    return cb(&instr->dest.dest, state);
1093 }
1094
1095 static bool
1096 visit_intrinsic_dest(nir_intrinsic_instr *instr, nir_foreach_dest_cb cb,
1097                      void *state)
1098 {
1099    if (nir_intrinsic_infos[instr->intrinsic].has_dest)
1100       return cb(&instr->dest, state);
1101
1102    return true;
1103 }
1104
1105 static bool
1106 visit_texture_dest(nir_tex_instr *instr, nir_foreach_dest_cb cb,
1107                    void *state)
1108 {
1109    return cb(&instr->dest, state);
1110 }
1111
1112 static bool
1113 visit_phi_dest(nir_phi_instr *instr, nir_foreach_dest_cb cb, void *state)
1114 {
1115    return cb(&instr->dest, state);
1116 }
1117
1118 static bool
1119 visit_parallel_copy_dest(nir_parallel_copy_instr *instr,
1120                          nir_foreach_dest_cb cb, void *state)
1121 {
1122    nir_foreach_parallel_copy_entry(entry, instr) {
1123       if (!cb(&entry->dest, state))
1124          return false;
1125    }
1126
1127    return true;
1128 }
1129
1130 bool
1131 nir_foreach_dest(nir_instr *instr, nir_foreach_dest_cb cb, void *state)
1132 {
1133    switch (instr->type) {
1134    case nir_instr_type_alu:
1135       return visit_alu_dest(nir_instr_as_alu(instr), cb, state);
1136    case nir_instr_type_intrinsic:
1137       return visit_intrinsic_dest(nir_instr_as_intrinsic(instr), cb, state);
1138    case nir_instr_type_tex:
1139       return visit_texture_dest(nir_instr_as_tex(instr), cb, state);
1140    case nir_instr_type_phi:
1141       return visit_phi_dest(nir_instr_as_phi(instr), cb, state);
1142    case nir_instr_type_parallel_copy:
1143       return visit_parallel_copy_dest(nir_instr_as_parallel_copy(instr),
1144                                       cb, state);
1145
1146    case nir_instr_type_load_const:
1147    case nir_instr_type_ssa_undef:
1148    case nir_instr_type_call:
1149    case nir_instr_type_jump:
1150       break;
1151
1152    default:
1153       unreachable("Invalid instruction type");
1154       break;
1155    }
1156
1157    return true;
1158 }
1159
1160 struct foreach_ssa_def_state {
1161    nir_foreach_ssa_def_cb cb;
1162    void *client_state;
1163 };
1164
1165 static inline bool
1166 nir_ssa_def_visitor(nir_dest *dest, void *void_state)
1167 {
1168    struct foreach_ssa_def_state *state = void_state;
1169
1170    if (dest->is_ssa)
1171       return state->cb(&dest->ssa, state->client_state);
1172    else
1173       return true;
1174 }
1175
1176 bool
1177 nir_foreach_ssa_def(nir_instr *instr, nir_foreach_ssa_def_cb cb, void *state)
1178 {
1179    switch (instr->type) {
1180    case nir_instr_type_alu:
1181    case nir_instr_type_tex:
1182    case nir_instr_type_intrinsic:
1183    case nir_instr_type_phi:
1184    case nir_instr_type_parallel_copy: {
1185       struct foreach_ssa_def_state foreach_state = {cb, state};
1186       return nir_foreach_dest(instr, nir_ssa_def_visitor, &foreach_state);
1187    }
1188
1189    case nir_instr_type_load_const:
1190       return cb(&nir_instr_as_load_const(instr)->def, state);
1191    case nir_instr_type_ssa_undef:
1192       return cb(&nir_instr_as_ssa_undef(instr)->def, state);
1193    case nir_instr_type_call:
1194    case nir_instr_type_jump:
1195       return true;
1196    default:
1197       unreachable("Invalid instruction type");
1198    }
1199 }
1200
1201 static bool
1202 visit_src(nir_src *src, nir_foreach_src_cb cb, void *state)
1203 {
1204    if (!cb(src, state))
1205       return false;
1206    if (!src->is_ssa && src->reg.indirect)
1207       return cb(src->reg.indirect, state);
1208    return true;
1209 }
1210
1211 static bool
1212 visit_deref_array_src(nir_deref_array *deref, nir_foreach_src_cb cb,
1213                       void *state)
1214 {
1215    if (deref->deref_array_type == nir_deref_array_type_indirect)
1216       return visit_src(&deref->indirect, cb, state);
1217    return true;
1218 }
1219
1220 static bool
1221 visit_deref_src(nir_deref_var *deref, nir_foreach_src_cb cb, void *state)
1222 {
1223    nir_deref *cur = &deref->deref;
1224    while (cur != NULL) {
1225       if (cur->deref_type == nir_deref_type_array) {
1226          if (!visit_deref_array_src(nir_deref_as_array(cur), cb, state))
1227             return false;
1228       }
1229
1230       cur = cur->child;
1231    }
1232
1233    return true;
1234 }
1235
1236 static bool
1237 visit_alu_src(nir_alu_instr *instr, nir_foreach_src_cb cb, void *state)
1238 {
1239    for (unsigned i = 0; i < nir_op_infos[instr->op].num_inputs; i++)
1240       if (!visit_src(&instr->src[i].src, cb, state))
1241          return false;
1242
1243    return true;
1244 }
1245
1246 static bool
1247 visit_tex_src(nir_tex_instr *instr, nir_foreach_src_cb cb, void *state)
1248 {
1249    for (unsigned i = 0; i < instr->num_srcs; i++) {
1250       if (!visit_src(&instr->src[i].src, cb, state))
1251          return false;
1252    }
1253
1254    if (instr->texture != NULL) {
1255       if (!visit_deref_src(instr->texture, cb, state))
1256          return false;
1257    }
1258
1259    if (instr->sampler != NULL) {
1260       if (!visit_deref_src(instr->sampler, cb, state))
1261          return false;
1262    }
1263
1264    return true;
1265 }
1266
1267 static bool
1268 visit_intrinsic_src(nir_intrinsic_instr *instr, nir_foreach_src_cb cb,
1269                     void *state)
1270 {
1271    unsigned num_srcs = nir_intrinsic_infos[instr->intrinsic].num_srcs;
1272    for (unsigned i = 0; i < num_srcs; i++) {
1273       if (!visit_src(&instr->src[i], cb, state))
1274          return false;
1275    }
1276
1277    unsigned num_vars =
1278       nir_intrinsic_infos[instr->intrinsic].num_variables;
1279    for (unsigned i = 0; i < num_vars; i++) {
1280       if (!visit_deref_src(instr->variables[i], cb, state))
1281          return false;
1282    }
1283
1284    return true;
1285 }
1286
1287 static bool
1288 visit_phi_src(nir_phi_instr *instr, nir_foreach_src_cb cb, void *state)
1289 {
1290    nir_foreach_phi_src(src, instr) {
1291       if (!visit_src(&src->src, cb, state))
1292          return false;
1293    }
1294
1295    return true;
1296 }
1297
1298 static bool
1299 visit_parallel_copy_src(nir_parallel_copy_instr *instr,
1300                         nir_foreach_src_cb cb, void *state)
1301 {
1302    nir_foreach_parallel_copy_entry(entry, instr) {
1303       if (!visit_src(&entry->src, cb, state))
1304          return false;
1305    }
1306
1307    return true;
1308 }
1309
1310 typedef struct {
1311    void *state;
1312    nir_foreach_src_cb cb;
1313 } visit_dest_indirect_state;
1314
1315 static bool
1316 visit_dest_indirect(nir_dest *dest, void *_state)
1317 {
1318    visit_dest_indirect_state *state = (visit_dest_indirect_state *) _state;
1319
1320    if (!dest->is_ssa && dest->reg.indirect)
1321       return state->cb(dest->reg.indirect, state->state);
1322
1323    return true;
1324 }
1325
1326 bool
1327 nir_foreach_src(nir_instr *instr, nir_foreach_src_cb cb, void *state)
1328 {
1329    switch (instr->type) {
1330    case nir_instr_type_alu:
1331       if (!visit_alu_src(nir_instr_as_alu(instr), cb, state))
1332          return false;
1333       break;
1334    case nir_instr_type_intrinsic:
1335       if (!visit_intrinsic_src(nir_instr_as_intrinsic(instr), cb, state))
1336          return false;
1337       break;
1338    case nir_instr_type_tex:
1339       if (!visit_tex_src(nir_instr_as_tex(instr), cb, state))
1340          return false;
1341       break;
1342    case nir_instr_type_call:
1343       /* Call instructions have no regular sources */
1344       break;
1345    case nir_instr_type_load_const:
1346       /* Constant load instructions have no regular sources */
1347       break;
1348    case nir_instr_type_phi:
1349       if (!visit_phi_src(nir_instr_as_phi(instr), cb, state))
1350          return false;
1351       break;
1352    case nir_instr_type_parallel_copy:
1353       if (!visit_parallel_copy_src(nir_instr_as_parallel_copy(instr),
1354                                    cb, state))
1355          return false;
1356       break;
1357    case nir_instr_type_jump:
1358    case nir_instr_type_ssa_undef:
1359       return true;
1360
1361    default:
1362       unreachable("Invalid instruction type");
1363       break;
1364    }
1365
1366    visit_dest_indirect_state dest_state;
1367    dest_state.state = state;
1368    dest_state.cb = cb;
1369    return nir_foreach_dest(instr, visit_dest_indirect, &dest_state);
1370 }
1371
1372 nir_const_value *
1373 nir_src_as_const_value(nir_src src)
1374 {
1375    if (!src.is_ssa)
1376       return NULL;
1377
1378    if (src.ssa->parent_instr->type != nir_instr_type_load_const)
1379       return NULL;
1380
1381    nir_load_const_instr *load = nir_instr_as_load_const(src.ssa->parent_instr);
1382
1383    return &load->value;
1384 }
1385
1386 /**
1387  * Returns true if the source is known to be dynamically uniform. Otherwise it
1388  * returns false which means it may or may not be dynamically uniform but it
1389  * can't be determined.
1390  */
1391 bool
1392 nir_src_is_dynamically_uniform(nir_src src)
1393 {
1394    if (!src.is_ssa)
1395       return false;
1396
1397    /* Constants are trivially dynamically uniform */
1398    if (src.ssa->parent_instr->type == nir_instr_type_load_const)
1399       return true;
1400
1401    /* As are uniform variables */
1402    if (src.ssa->parent_instr->type == nir_instr_type_intrinsic) {
1403       nir_intrinsic_instr *intr = nir_instr_as_intrinsic(src.ssa->parent_instr);
1404
1405       if (intr->intrinsic == nir_intrinsic_load_uniform)
1406          return true;
1407    }
1408
1409    /* XXX: this could have many more tests, such as when a sampler function is
1410     * called with dynamically uniform arguments.
1411     */
1412    return false;
1413 }
1414
1415 static void
1416 src_remove_all_uses(nir_src *src)
1417 {
1418    for (; src; src = src->is_ssa ? NULL : src->reg.indirect) {
1419       if (!src_is_valid(src))
1420          continue;
1421
1422       list_del(&src->use_link);
1423    }
1424 }
1425
1426 static void
1427 src_add_all_uses(nir_src *src, nir_instr *parent_instr, nir_if *parent_if)
1428 {
1429    for (; src; src = src->is_ssa ? NULL : src->reg.indirect) {
1430       if (!src_is_valid(src))
1431          continue;
1432
1433       if (parent_instr) {
1434          src->parent_instr = parent_instr;
1435          if (src->is_ssa)
1436             list_addtail(&src->use_link, &src->ssa->uses);
1437          else
1438             list_addtail(&src->use_link, &src->reg.reg->uses);
1439       } else {
1440          assert(parent_if);
1441          src->parent_if = parent_if;
1442          if (src->is_ssa)
1443             list_addtail(&src->use_link, &src->ssa->if_uses);
1444          else
1445             list_addtail(&src->use_link, &src->reg.reg->if_uses);
1446       }
1447    }
1448 }
1449
1450 void
1451 nir_instr_rewrite_src(nir_instr *instr, nir_src *src, nir_src new_src)
1452 {
1453    assert(!src_is_valid(src) || src->parent_instr == instr);
1454
1455    src_remove_all_uses(src);
1456    *src = new_src;
1457    src_add_all_uses(src, instr, NULL);
1458 }
1459
1460 void
1461 nir_instr_move_src(nir_instr *dest_instr, nir_src *dest, nir_src *src)
1462 {
1463    assert(!src_is_valid(dest) || dest->parent_instr == dest_instr);
1464
1465    src_remove_all_uses(dest);
1466    src_remove_all_uses(src);
1467    *dest = *src;
1468    *src = NIR_SRC_INIT;
1469    src_add_all_uses(dest, dest_instr, NULL);
1470 }
1471
1472 void
1473 nir_if_rewrite_condition(nir_if *if_stmt, nir_src new_src)
1474 {
1475    nir_src *src = &if_stmt->condition;
1476    assert(!src_is_valid(src) || src->parent_if == if_stmt);
1477
1478    src_remove_all_uses(src);
1479    *src = new_src;
1480    src_add_all_uses(src, NULL, if_stmt);
1481 }
1482
1483 void
1484 nir_instr_rewrite_dest(nir_instr *instr, nir_dest *dest, nir_dest new_dest)
1485 {
1486    if (dest->is_ssa) {
1487       /* We can only overwrite an SSA destination if it has no uses. */
1488       assert(list_empty(&dest->ssa.uses) && list_empty(&dest->ssa.if_uses));
1489    } else {
1490       list_del(&dest->reg.def_link);
1491       if (dest->reg.indirect)
1492          src_remove_all_uses(dest->reg.indirect);
1493    }
1494
1495    /* We can't re-write with an SSA def */
1496    assert(!new_dest.is_ssa);
1497
1498    nir_dest_copy(dest, &new_dest, instr);
1499
1500    dest->reg.parent_instr = instr;
1501    list_addtail(&dest->reg.def_link, &new_dest.reg.reg->defs);
1502
1503    if (dest->reg.indirect)
1504       src_add_all_uses(dest->reg.indirect, instr, NULL);
1505 }
1506
1507 /* note: does *not* take ownership of 'name' */
1508 void
1509 nir_ssa_def_init(nir_instr *instr, nir_ssa_def *def,
1510                  unsigned num_components,
1511                  unsigned bit_size, const char *name)
1512 {
1513    def->name = ralloc_strdup(instr, name);
1514    def->parent_instr = instr;
1515    list_inithead(&def->uses);
1516    list_inithead(&def->if_uses);
1517    def->num_components = num_components;
1518    def->bit_size = bit_size;
1519
1520    if (instr->block) {
1521       nir_function_impl *impl =
1522          nir_cf_node_get_function(&instr->block->cf_node);
1523
1524       def->index = impl->ssa_alloc++;
1525    } else {
1526       def->index = UINT_MAX;
1527    }
1528 }
1529
1530 /* note: does *not* take ownership of 'name' */
1531 void
1532 nir_ssa_dest_init(nir_instr *instr, nir_dest *dest,
1533                  unsigned num_components, unsigned bit_size,
1534                  const char *name)
1535 {
1536    dest->is_ssa = true;
1537    nir_ssa_def_init(instr, &dest->ssa, num_components, bit_size, name);
1538 }
1539
1540 void
1541 nir_ssa_def_rewrite_uses(nir_ssa_def *def, nir_src new_src)
1542 {
1543    assert(!new_src.is_ssa || def != new_src.ssa);
1544
1545    nir_foreach_use_safe(use_src, def)
1546       nir_instr_rewrite_src(use_src->parent_instr, use_src, new_src);
1547
1548    nir_foreach_if_use_safe(use_src, def)
1549       nir_if_rewrite_condition(use_src->parent_if, new_src);
1550 }
1551
1552 static bool
1553 is_instr_between(nir_instr *start, nir_instr *end, nir_instr *between)
1554 {
1555    assert(start->block == end->block);
1556
1557    if (between->block != start->block)
1558       return false;
1559
1560    /* Search backwards looking for "between" */
1561    while (start != end) {
1562       if (between == end)
1563          return true;
1564
1565       end = nir_instr_prev(end);
1566       assert(end);
1567    }
1568
1569    return false;
1570 }
1571
1572 /* Replaces all uses of the given SSA def with the given source but only if
1573  * the use comes after the after_me instruction.  This can be useful if you
1574  * are emitting code to fix up the result of some instruction: you can freely
1575  * use the result in that code and then call rewrite_uses_after and pass the
1576  * last fixup instruction as after_me and it will replace all of the uses you
1577  * want without touching the fixup code.
1578  *
1579  * This function assumes that after_me is in the same block as
1580  * def->parent_instr and that after_me comes after def->parent_instr.
1581  */
1582 void
1583 nir_ssa_def_rewrite_uses_after(nir_ssa_def *def, nir_src new_src,
1584                                nir_instr *after_me)
1585 {
1586    assert(!new_src.is_ssa || def != new_src.ssa);
1587
1588    nir_foreach_use_safe(use_src, def) {
1589       assert(use_src->parent_instr != def->parent_instr);
1590       /* Since def already dominates all of its uses, the only way a use can
1591        * not be dominated by after_me is if it is between def and after_me in
1592        * the instruction list.
1593        */
1594       if (!is_instr_between(def->parent_instr, after_me, use_src->parent_instr))
1595          nir_instr_rewrite_src(use_src->parent_instr, use_src, new_src);
1596    }
1597
1598    nir_foreach_if_use_safe(use_src, def)
1599       nir_if_rewrite_condition(use_src->parent_if, new_src);
1600 }
1601
1602 uint8_t
1603 nir_ssa_def_components_read(nir_ssa_def *def)
1604 {
1605    uint8_t read_mask = 0;
1606    nir_foreach_use(use, def) {
1607       if (use->parent_instr->type == nir_instr_type_alu) {
1608          nir_alu_instr *alu = nir_instr_as_alu(use->parent_instr);
1609          nir_alu_src *alu_src = exec_node_data(nir_alu_src, use, src);
1610          int src_idx = alu_src - &alu->src[0];
1611          assert(src_idx >= 0 && src_idx < nir_op_infos[alu->op].num_inputs);
1612
1613          for (unsigned c = 0; c < 4; c++) {
1614             if (!nir_alu_instr_channel_used(alu, src_idx, c))
1615                continue;
1616
1617             read_mask |= (1 << alu_src->swizzle[c]);
1618          }
1619       } else {
1620          return (1 << def->num_components) - 1;
1621       }
1622    }
1623
1624    return read_mask;
1625 }
1626
1627 nir_block *
1628 nir_block_cf_tree_next(nir_block *block)
1629 {
1630    if (block == NULL) {
1631       /* nir_foreach_block_safe() will call this function on a NULL block
1632        * after the last iteration, but it won't use the result so just return
1633        * NULL here.
1634        */
1635       return NULL;
1636    }
1637
1638    nir_cf_node *cf_next = nir_cf_node_next(&block->cf_node);
1639    if (cf_next)
1640       return nir_cf_node_cf_tree_first(cf_next);
1641
1642    nir_cf_node *parent = block->cf_node.parent;
1643
1644    switch (parent->type) {
1645    case nir_cf_node_if: {
1646       /* Are we at the end of the if? Go to the beginning of the else */
1647       nir_if *if_stmt = nir_cf_node_as_if(parent);
1648       if (block == nir_if_last_then_block(if_stmt))
1649          return nir_if_first_else_block(if_stmt);
1650
1651       assert(block == nir_if_last_else_block(if_stmt));
1652       /* fall through */
1653    }
1654
1655    case nir_cf_node_loop:
1656       return nir_cf_node_as_block(nir_cf_node_next(parent));
1657
1658    case nir_cf_node_function:
1659       return NULL;
1660
1661    default:
1662       unreachable("unknown cf node type");
1663    }
1664 }
1665
1666 nir_block *
1667 nir_block_cf_tree_prev(nir_block *block)
1668 {
1669    if (block == NULL) {
1670       /* do this for consistency with nir_block_cf_tree_next() */
1671       return NULL;
1672    }
1673
1674    nir_cf_node *cf_prev = nir_cf_node_prev(&block->cf_node);
1675    if (cf_prev)
1676       return nir_cf_node_cf_tree_last(cf_prev);
1677
1678    nir_cf_node *parent = block->cf_node.parent;
1679
1680    switch (parent->type) {
1681    case nir_cf_node_if: {
1682       /* Are we at the beginning of the else? Go to the end of the if */
1683       nir_if *if_stmt = nir_cf_node_as_if(parent);
1684       if (block == nir_if_first_else_block(if_stmt))
1685          return nir_if_last_then_block(if_stmt);
1686
1687       assert(block == nir_if_first_then_block(if_stmt));
1688       /* fall through */
1689    }
1690
1691    case nir_cf_node_loop:
1692       return nir_cf_node_as_block(nir_cf_node_prev(parent));
1693
1694    case nir_cf_node_function:
1695       return NULL;
1696
1697    default:
1698       unreachable("unknown cf node type");
1699    }
1700 }
1701
1702 nir_block *nir_cf_node_cf_tree_first(nir_cf_node *node)
1703 {
1704    switch (node->type) {
1705    case nir_cf_node_function: {
1706       nir_function_impl *impl = nir_cf_node_as_function(node);
1707       return nir_start_block(impl);
1708    }
1709
1710    case nir_cf_node_if: {
1711       nir_if *if_stmt = nir_cf_node_as_if(node);
1712       return nir_if_first_then_block(if_stmt);
1713    }
1714
1715    case nir_cf_node_loop: {
1716       nir_loop *loop = nir_cf_node_as_loop(node);
1717       return nir_loop_first_block(loop);
1718    }
1719
1720    case nir_cf_node_block: {
1721       return nir_cf_node_as_block(node);
1722    }
1723
1724    default:
1725       unreachable("unknown node type");
1726    }
1727 }
1728
1729 nir_block *nir_cf_node_cf_tree_last(nir_cf_node *node)
1730 {
1731    switch (node->type) {
1732    case nir_cf_node_function: {
1733       nir_function_impl *impl = nir_cf_node_as_function(node);
1734       return nir_impl_last_block(impl);
1735    }
1736
1737    case nir_cf_node_if: {
1738       nir_if *if_stmt = nir_cf_node_as_if(node);
1739       return nir_if_last_else_block(if_stmt);
1740    }
1741
1742    case nir_cf_node_loop: {
1743       nir_loop *loop = nir_cf_node_as_loop(node);
1744       return nir_loop_last_block(loop);
1745    }
1746
1747    case nir_cf_node_block: {
1748       return nir_cf_node_as_block(node);
1749    }
1750
1751    default:
1752       unreachable("unknown node type");
1753    }
1754 }
1755
1756 nir_block *nir_cf_node_cf_tree_next(nir_cf_node *node)
1757 {
1758    if (node->type == nir_cf_node_block)
1759       return nir_block_cf_tree_next(nir_cf_node_as_block(node));
1760    else if (node->type == nir_cf_node_function)
1761       return NULL;
1762    else
1763       return nir_cf_node_as_block(nir_cf_node_next(node));
1764 }
1765
1766 nir_if *
1767 nir_block_get_following_if(nir_block *block)
1768 {
1769    if (exec_node_is_tail_sentinel(&block->cf_node.node))
1770       return NULL;
1771
1772    if (nir_cf_node_is_last(&block->cf_node))
1773       return NULL;
1774
1775    nir_cf_node *next_node = nir_cf_node_next(&block->cf_node);
1776
1777    if (next_node->type != nir_cf_node_if)
1778       return NULL;
1779
1780    return nir_cf_node_as_if(next_node);
1781 }
1782
1783 nir_loop *
1784 nir_block_get_following_loop(nir_block *block)
1785 {
1786    if (exec_node_is_tail_sentinel(&block->cf_node.node))
1787       return NULL;
1788
1789    if (nir_cf_node_is_last(&block->cf_node))
1790       return NULL;
1791
1792    nir_cf_node *next_node = nir_cf_node_next(&block->cf_node);
1793
1794    if (next_node->type != nir_cf_node_loop)
1795       return NULL;
1796
1797    return nir_cf_node_as_loop(next_node);
1798 }
1799
1800 void
1801 nir_index_blocks(nir_function_impl *impl)
1802 {
1803    unsigned index = 0;
1804
1805    if (impl->valid_metadata & nir_metadata_block_index)
1806       return;
1807
1808    nir_foreach_block(block, impl) {
1809       block->index = index++;
1810    }
1811
1812    impl->num_blocks = index;
1813 }
1814
1815 static bool
1816 index_ssa_def_cb(nir_ssa_def *def, void *state)
1817 {
1818    unsigned *index = (unsigned *) state;
1819    def->index = (*index)++;
1820
1821    return true;
1822 }
1823
1824 /**
1825  * The indices are applied top-to-bottom which has the very nice property
1826  * that, if A dominates B, then A->index <= B->index.
1827  */
1828 void
1829 nir_index_ssa_defs(nir_function_impl *impl)
1830 {
1831    unsigned index = 0;
1832
1833    nir_foreach_block(block, impl) {
1834       nir_foreach_instr(instr, block)
1835          nir_foreach_ssa_def(instr, index_ssa_def_cb, &index);
1836    }
1837
1838    impl->ssa_alloc = index;
1839 }
1840
1841 /**
1842  * The indices are applied top-to-bottom which has the very nice property
1843  * that, if A dominates B, then A->index <= B->index.
1844  */
1845 unsigned
1846 nir_index_instrs(nir_function_impl *impl)
1847 {
1848    unsigned index = 0;
1849
1850    nir_foreach_block(block, impl) {
1851       nir_foreach_instr(instr, block)
1852          instr->index = index++;
1853    }
1854
1855    return index;
1856 }
1857
1858 nir_intrinsic_op
1859 nir_intrinsic_from_system_value(gl_system_value val)
1860 {
1861    switch (val) {
1862    case SYSTEM_VALUE_VERTEX_ID:
1863       return nir_intrinsic_load_vertex_id;
1864    case SYSTEM_VALUE_INSTANCE_ID:
1865       return nir_intrinsic_load_instance_id;
1866    case SYSTEM_VALUE_DRAW_ID:
1867       return nir_intrinsic_load_draw_id;
1868    case SYSTEM_VALUE_BASE_INSTANCE:
1869       return nir_intrinsic_load_base_instance;
1870    case SYSTEM_VALUE_VERTEX_ID_ZERO_BASE:
1871       return nir_intrinsic_load_vertex_id_zero_base;
1872    case SYSTEM_VALUE_BASE_VERTEX:
1873       return nir_intrinsic_load_base_vertex;
1874    case SYSTEM_VALUE_INVOCATION_ID:
1875       return nir_intrinsic_load_invocation_id;
1876    case SYSTEM_VALUE_FRONT_FACE:
1877       return nir_intrinsic_load_front_face;
1878    case SYSTEM_VALUE_SAMPLE_ID:
1879       return nir_intrinsic_load_sample_id;
1880    case SYSTEM_VALUE_SAMPLE_POS:
1881       return nir_intrinsic_load_sample_pos;
1882    case SYSTEM_VALUE_SAMPLE_MASK_IN:
1883       return nir_intrinsic_load_sample_mask_in;
1884    case SYSTEM_VALUE_LOCAL_INVOCATION_ID:
1885       return nir_intrinsic_load_local_invocation_id;
1886    case SYSTEM_VALUE_LOCAL_INVOCATION_INDEX:
1887       return nir_intrinsic_load_local_invocation_index;
1888    case SYSTEM_VALUE_WORK_GROUP_ID:
1889       return nir_intrinsic_load_work_group_id;
1890    case SYSTEM_VALUE_NUM_WORK_GROUPS:
1891       return nir_intrinsic_load_num_work_groups;
1892    case SYSTEM_VALUE_PRIMITIVE_ID:
1893       return nir_intrinsic_load_primitive_id;
1894    case SYSTEM_VALUE_TESS_COORD:
1895       return nir_intrinsic_load_tess_coord;
1896    case SYSTEM_VALUE_TESS_LEVEL_OUTER:
1897       return nir_intrinsic_load_tess_level_outer;
1898    case SYSTEM_VALUE_TESS_LEVEL_INNER:
1899       return nir_intrinsic_load_tess_level_inner;
1900    case SYSTEM_VALUE_VERTICES_IN:
1901       return nir_intrinsic_load_patch_vertices_in;
1902    case SYSTEM_VALUE_HELPER_INVOCATION:
1903       return nir_intrinsic_load_helper_invocation;
1904    default:
1905       unreachable("system value does not directly correspond to intrinsic");
1906    }
1907 }
1908
1909 gl_system_value
1910 nir_system_value_from_intrinsic(nir_intrinsic_op intrin)
1911 {
1912    switch (intrin) {
1913    case nir_intrinsic_load_vertex_id:
1914       return SYSTEM_VALUE_VERTEX_ID;
1915    case nir_intrinsic_load_instance_id:
1916       return SYSTEM_VALUE_INSTANCE_ID;
1917    case nir_intrinsic_load_draw_id:
1918       return SYSTEM_VALUE_DRAW_ID;
1919    case nir_intrinsic_load_base_instance:
1920       return SYSTEM_VALUE_BASE_INSTANCE;
1921    case nir_intrinsic_load_vertex_id_zero_base:
1922       return SYSTEM_VALUE_VERTEX_ID_ZERO_BASE;
1923    case nir_intrinsic_load_base_vertex:
1924       return SYSTEM_VALUE_BASE_VERTEX;
1925    case nir_intrinsic_load_invocation_id:
1926       return SYSTEM_VALUE_INVOCATION_ID;
1927    case nir_intrinsic_load_front_face:
1928       return SYSTEM_VALUE_FRONT_FACE;
1929    case nir_intrinsic_load_sample_id:
1930       return SYSTEM_VALUE_SAMPLE_ID;
1931    case nir_intrinsic_load_sample_pos:
1932       return SYSTEM_VALUE_SAMPLE_POS;
1933    case nir_intrinsic_load_sample_mask_in:
1934       return SYSTEM_VALUE_SAMPLE_MASK_IN;
1935    case nir_intrinsic_load_local_invocation_id:
1936       return SYSTEM_VALUE_LOCAL_INVOCATION_ID;
1937    case nir_intrinsic_load_local_invocation_index:
1938       return SYSTEM_VALUE_LOCAL_INVOCATION_INDEX;
1939    case nir_intrinsic_load_num_work_groups:
1940       return SYSTEM_VALUE_NUM_WORK_GROUPS;
1941    case nir_intrinsic_load_work_group_id:
1942       return SYSTEM_VALUE_WORK_GROUP_ID;
1943    case nir_intrinsic_load_primitive_id:
1944       return SYSTEM_VALUE_PRIMITIVE_ID;
1945    case nir_intrinsic_load_tess_coord:
1946       return SYSTEM_VALUE_TESS_COORD;
1947    case nir_intrinsic_load_tess_level_outer:
1948       return SYSTEM_VALUE_TESS_LEVEL_OUTER;
1949    case nir_intrinsic_load_tess_level_inner:
1950       return SYSTEM_VALUE_TESS_LEVEL_INNER;
1951    case nir_intrinsic_load_patch_vertices_in:
1952       return SYSTEM_VALUE_VERTICES_IN;
1953    case nir_intrinsic_load_helper_invocation:
1954       return SYSTEM_VALUE_HELPER_INVOCATION;
1955    default:
1956       unreachable("intrinsic doesn't produce a system value");
1957    }
1958 }
1959
1960 nir_op
1961 nir_type_conversion_op(nir_alu_type src, nir_alu_type dst)
1962 {
1963    nir_alu_type src_base_type = (nir_alu_type) nir_alu_type_get_base_type(src);
1964    nir_alu_type dst_base_type = (nir_alu_type) nir_alu_type_get_base_type(dst);
1965    unsigned src_bitsize = nir_alu_type_get_type_size(src);
1966    unsigned dst_bitsize = nir_alu_type_get_type_size(dst);
1967
1968    if (src_base_type == dst_base_type) {
1969       if (src_bitsize == dst_bitsize)
1970          return (src_base_type == nir_type_float) ? nir_op_fmov : nir_op_imov;
1971
1972       assert (src_base_type == nir_type_float);
1973       /* TODO: implement support for float16 */
1974       assert(src_bitsize == 64 || dst_bitsize == 64);
1975       return (src_bitsize == 64) ? nir_op_d2f : nir_op_f2d;
1976    }
1977
1978    /* Different base type but same bit_size */
1979    if (src_bitsize == dst_bitsize) {
1980       /* TODO: This does not include specific conversions between
1981        * signed or unsigned integer types of bit size different than 32 yet.
1982        */
1983       assert(src_bitsize == 32);
1984       switch (src_base_type) {
1985       case nir_type_uint:
1986          return (dst_base_type == nir_type_float) ? nir_op_u2f : nir_op_imov;
1987       case nir_type_int:
1988          return (dst_base_type == nir_type_float) ? nir_op_i2f : nir_op_imov;
1989       case nir_type_bool:
1990          return (dst_base_type == nir_type_float) ? nir_op_b2f : nir_op_b2i;
1991       case nir_type_float:
1992          switch (dst_base_type) {
1993          case nir_type_uint:
1994             return nir_op_f2u;
1995          case nir_type_bool:
1996             return nir_op_f2b;
1997          default:
1998             return nir_op_f2i;
1999          };
2000       default:
2001          assert(!"Invalid conversion");
2002       };
2003    }
2004
2005    /* Different bit_size and different base type */
2006    /* TODO: Implement integer support for types with bit_size != 32 */
2007    switch (src_base_type) {
2008    case nir_type_uint:
2009       assert(dst == nir_type_float64);
2010       return nir_op_u2d;
2011    case nir_type_int:
2012       assert(dst == nir_type_float64);
2013       return nir_op_i2d;
2014    case nir_type_bool:
2015       assert(dst == nir_type_float64);
2016       return nir_op_u2d;
2017    case nir_type_float:
2018       assert(src_bitsize == 32 || src_bitsize == 64);
2019       if (src_bitsize != 64) {
2020          assert(dst == nir_type_float64);
2021          return nir_op_f2d;
2022       }
2023       assert(dst_bitsize == 32);
2024       switch (dst_base_type) {
2025       case nir_type_uint:
2026          return nir_op_d2u;
2027       case nir_type_int:
2028          return nir_op_d2i;
2029       case nir_type_bool:
2030          return nir_op_d2b;
2031       case nir_type_float:
2032          return nir_op_d2f;
2033       default:
2034          assert(!"Invalid conversion");
2035       };
2036    default:
2037       assert(!"Invalid conversion");
2038    };
2039 }