source/glsl/generate.cpp

   1 #include <msp/core/hash.h>
   2 #include <msp/core/raii.h>
   3 #include <msp/strings/lexicalcast.h>
   4 #include "builtin.h"
   5 #include "generate.h"
   6
   7 using namespace std;
   8
   9 namespace Msp {
  10 namespace GL {
  11 namespace SL {
  12
  13 void DeclarationCombiner::apply(Stage &stage)
  14 {
  15         stage.content.visit(*this);
  16         NodeRemover().apply(stage, nodes_to_remove);
  17 }
  18
  19 void DeclarationCombiner::visit(Block &block)
  20 {
  21         if(current_block)
  22                 return;
  23
  24         TraversingVisitor::visit(block);
  25 }
  26
  27 void DeclarationCombiner::visit(VariableDeclaration &var)
  28 {
  29         VariableDeclaration *&ptr = variables[var.name];
  30         if(ptr)
  31         {
  32                 ptr->type = var.type;
  33                 if(var.init_expression)
  34                         ptr->init_expression = var.init_expression;
  35                 if(var.layout)
  36                 {
  37                         if(ptr->layout)
  38                         {
  39                                 for(vector<Layout::Qualifier>::iterator i=var.layout->qualifiers.begin(); i!=var.layout->qualifiers.end(); ++i)
  40                                 {
  41                                         bool found = false;
  42                                         for(vector<Layout::Qualifier>::iterator j=ptr->layout->qualifiers.begin(); (!found && j!=ptr->layout->qualifiers.end()); ++j)
  43                                                 if(j->name==i->name)
  44                                                 {
  45                                                         j->has_value = i->value;
  46                                                         j->value = i->value;
  47                                                         found = true;
  48                                                 }
  49
  50                                         if(!found)
  51                                                 ptr->layout->qualifiers.push_back(*i);
  52                                 }
  53                         }
  54                         else
  55                                 ptr->layout = var.layout;
  56                 }
  57                 nodes_to_remove.insert(&var);
  58         }
  59         else
  60                 ptr = &var;
  61 }
  62
  63
  64 ConstantSpecializer::ConstantSpecializer():
  65         values(0)
  66 { }
  67
  68 void ConstantSpecializer::apply(Stage &stage, const map<string, int> *v)
  69 {
  70         values = v;
  71         stage.content.visit(*this);
  72 }
  73
  74 void ConstantSpecializer::visit(VariableDeclaration &var)
  75 {
  76         bool specializable = false;
  77         if(var.layout)
  78         {
  79                 vector<Layout::Qualifier> &qualifiers = var.layout->qualifiers;
  80                 for(vector<Layout::Qualifier>::iterator i=qualifiers.begin(); i!=qualifiers.end(); ++i)
  81                         if(i->name=="constant_id")
  82                         {
  83                                 specializable = true;
  84                                 if(values)
  85                                         qualifiers.erase(i);
  86                                 else if(i->value==-1)
  87                                         i->value = hash32(var.name)&0x7FFFFFFF;
  88                                 break;
  89                         }
  90
  91                 if(qualifiers.empty())
  92                         var.layout = 0;
  93         }
  94
  95         if(specializable && values)
  96         {
  97                 map<string, int>::const_iterator i = values->find(var.name);
  98                 if(i!=values->end())
  99                 {
 100                         RefPtr<Literal> literal = new Literal;
 101                         if(var.type=="bool")
 102                                 literal->token = (i->second ? "true" : "false");
 103                         else if(var.type=="int")
 104                                 literal->token = lexical_cast<string>(i->second);
 105                         var.init_expression = literal;
 106                 }
 107         }
 108 }
 109
 110
 111 void BlockHierarchyResolver::enter(Block &block)
 112 {
 113         block.parent = current_block;
 114 }
 115
 116
 117 VariableResolver::VariableResolver():
 118         stage(0),
 119         r_members(0),
 120         record_target(false),
 121         r_self_referencing(false),
 122         r_assignment_target(0)
 123 { }
 124
 125 void VariableResolver::apply(Stage &s)
 126 {
 127         stage = &s;
 128         s.types.clear();
 129         s.interface_blocks.clear();
 130         s.content.visit(*this);
 131 }
 132
 133 void VariableResolver::enter(Block &block)
 134 {
 135         block.variables.clear();
 136 }
 137
 138 void VariableResolver::visit(VariableReference &var)
 139 {
 140         var.declaration = 0;
 141         r_members = 0;
 142         /* Look for variable declarations in the block hierarchy first.  Interface
 143         blocks are always defined in the top level so we can't accidentally skip
 144         one. */
 145         for(Block *block=current_block; (!var.declaration && block); block=block->parent)
 146         {
 147                 map<string, VariableDeclaration *>::iterator i = block->variables.find(var.name);
 148                 if(i!=block->variables.end())
 149                         var.declaration = i->second;
 150         }
 151
 152         if(var.declaration)
 153         {
 154                 if(var.declaration->type_declaration)
 155                         r_members = &var.declaration->type_declaration->members.variables;
 156         }
 157         else
 158         {
 159                 const map<string, InterfaceBlock *> &blocks = stage->interface_blocks;
 160                 map<string, InterfaceBlock *>::const_iterator i = blocks.find("_"+var.name);
 161                 if(i!=blocks.end())
 162                 {
 163                         /* The name refers to an interface block with an instance name rather
 164                         than a variable.  Prepare a new syntax tree node accordingly. */
 165                         r_iface_ref = new InterfaceBlockReference;
 166                         r_iface_ref->name = var.name;
 167                         r_iface_ref->declaration = i->second;
 168                         r_members = &i->second->members.variables;
 169                 }
 170                 else
 171                 {
 172                         // Look for the variable in anonymous interface blocks.
 173                         for(i=blocks.begin(); (!var.declaration && i!=blocks.end()); ++i)
 174                                 if(i->second->instance_name.empty())
 175                                 {
 176                                         map<string, VariableDeclaration *>::iterator j = i->second->members.variables.find(var.name);
 177                                         if(j!=i->second->members.variables.end())
 178                                                 var.declaration = j->second;
 179                                 }
 180                 }
 181         }
 182
 183         if(record_target)
 184         {
 185                 if(r_assignment_target)
 186                 {
 187                         /* More than one variable reference found in assignment target.
 188                         Unable to determine what the primary target is. */
 189                         record_target = false;
 190                         r_assignment_target = 0;
 191                 }
 192                 else
 193                         r_assignment_target = var.declaration;
 194         }
 195         else if(var.declaration && var.declaration==r_assignment_target)
 196                 r_self_referencing = true;
 197 }
 198
 199 void VariableResolver::visit(InterfaceBlockReference &iface)
 200 {
 201         iface.declaration = 0;
 202         for(Block *block=current_block; block; block=block->parent)
 203         {
 204                 map<string, InterfaceBlock *>::iterator i = stage->interface_blocks.find("_"+iface.name);
 205                 if(i!=stage->interface_blocks.end())
 206                 {
 207                         iface.declaration = i->second;
 208                         r_members = &i->second->members.variables;
 209                         break;
 210                 }
 211         }
 212 }
 213
 214 void VariableResolver::visit(MemberAccess &memacc)
 215 {
 216         r_members = 0;
 217         r_iface_ref = 0;
 218         memacc.left->visit(*this);
 219
 220         if(r_iface_ref)
 221                 memacc.left = r_iface_ref;
 222         r_iface_ref = 0;
 223
 224         memacc.declaration = 0;
 225         if(r_members)
 226         {
 227                 map<string, VariableDeclaration *>::iterator i = r_members->find(memacc.member);
 228                 if(i!=r_members->end())
 229                 {
 230                         memacc.declaration = i->second;
 231                         if(i->second->type_declaration)
 232                                 r_members = &i->second->type_declaration->members.variables;
 233                 }
 234                 else
 235                         r_members = 0;
 236         }
 237 }
 238
 239 void VariableResolver::visit(UnaryExpression &unary)
 240 {
 241         TraversingVisitor::visit(unary);
 242         r_members = 0;
 243         r_iface_ref = 0;
 244 }
 245
 246 void VariableResolver::visit(BinaryExpression &binary)
 247 {
 248         if(binary.oper->token[0]=='[')
 249         {
 250                 {
 251                         /* The subscript expression is not a part of the primary assignment
 252                         target. */
 253                         SetFlag set(record_target, false);
 254                         binary.right->visit(*this);
 255                 }
 256                 r_members = 0;
 257                 r_iface_ref = 0;
 258                 binary.left->visit(*this);
 259                 if(r_iface_ref)
 260                         binary.left = r_iface_ref;
 261         }
 262         else
 263         {
 264                 TraversingVisitor::visit(binary);
 265                 r_members = 0;
 266         }
 267
 268         r_iface_ref = 0;
 269 }
 270
 271 void VariableResolver::visit(Assignment &assign)
 272 {
 273         {
 274                 SetFlag set(record_target);
 275                 r_assignment_target = 0;
 276                 assign.left->visit(*this);
 277                 assign.target_declaration = r_assignment_target;
 278         }
 279
 280         r_self_referencing = false;
 281         assign.right->visit(*this);
 282         assign.self_referencing = (r_self_referencing || assign.oper->token[0]!='=');
 283
 284         r_members = 0;
 285         r_iface_ref = 0;
 286 }
 287
 288 void VariableResolver::visit(FunctionCall &call)
 289 {
 290         TraversingVisitor::visit(call);
 291         r_members = 0;
 292         r_iface_ref = 0;
 293 }
 294
 295 void VariableResolver::visit(StructDeclaration &strct)
 296 {
 297         TraversingVisitor::visit(strct);
 298         stage->types.insert(make_pair(strct.name, &strct));
 299 }
 300
 301 void VariableResolver::visit(VariableDeclaration &var)
 302 {
 303         map<string, StructDeclaration *>::iterator i = stage->types.find(var.type);
 304         if(i!=stage->types.end())
 305                 var.type_declaration = i->second;
 306
 307         if(!block_interface.empty() && var.interface.empty())
 308                 var.interface = block_interface;
 309
 310         TraversingVisitor::visit(var);
 311         current_block->variables.insert(make_pair(var.name, &var));
 312 }
 313
 314 void VariableResolver::visit(InterfaceBlock &iface)
 315 {
 316         /* Block names can be reused in different interfaces.  Prefix the name with
 317         the first character of the interface to avoid conflicts. */
 318         stage->interface_blocks.insert(make_pair(iface.interface+iface.name, &iface));
 319         if(!iface.instance_name.empty())
 320                 stage->interface_blocks.insert(make_pair("_"+iface.instance_name, &iface));
 321
 322         SetForScope<string> set_iface(block_interface, iface.interface);
 323         TraversingVisitor::visit(iface);
 324 }
 325
 326
 327 void FunctionResolver::apply(Stage &s)
 328 {
 329         stage = &s;
 330         s.functions.clear();
 331         s.content.visit(*this);
 332 }
 333
 334 void FunctionResolver::visit(FunctionCall &call)
 335 {
 336         map<string, FunctionDeclaration *>::iterator i = stage->functions.find(call.name);
 337         if(i!=stage->functions.end())
 338                 call.declaration = i->second;
 339
 340         TraversingVisitor::visit(call);
 341 }
 342
 343 void FunctionResolver::visit(FunctionDeclaration &func)
 344 {
 345         FunctionDeclaration *&stage_decl = stage->functions[func.name];
 346         vector<FunctionDeclaration *> &decls = declarations[func.name];
 347         if(func.definition==&func)
 348         {
 349                 stage_decl = &func;
 350
 351                 // Set all previous declarations to use this definition.
 352                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 353                 {
 354                         (*i)->definition = func.definition;
 355                         (*i)->body.body.clear();
 356                 }
 357         }
 358         else
 359         {
 360                 func.definition = 0;
 361                 if(!stage_decl)
 362                         stage_decl = &func;
 363                 else
 364                         func.definition = stage_decl->definition;
 365         }
 366         decls.push_back(&func);
 367
 368         TraversingVisitor::visit(func);
 369 }
 370
 371
 372 InterfaceGenerator::InterfaceGenerator():
 373         stage(0),
 374         function_scope(false),
 375         iface_block(0),
 376         copy_block(false),
 377         iface_target_block(0)
 378 { }
 379
 380 string InterfaceGenerator::get_out_prefix(Stage::Type type)
 381 {
 382         if(type==Stage::VERTEX)
 383                 return "_vs_out_";
 384         else if(type==Stage::GEOMETRY)
 385                 return "_gs_out_";
 386         else
 387                 return string();
 388 }
 389
 390 void InterfaceGenerator::apply(Stage &s)
 391 {
 392         stage = &s;
 393         iface_target_block = &stage->content;
 394         if(stage->previous)
 395                 in_prefix = get_out_prefix(stage->previous->type);
 396         out_prefix = get_out_prefix(stage->type);
 397         s.content.visit(*this);
 398         NodeRemover().apply(s, nodes_to_remove);
 399 }
 400
 401 void InterfaceGenerator::visit(Block &block)
 402 {
 403         SetForScope<Block *> set_block(current_block, &block);
 404         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 405         {
 406                 assignment_insert_point = i;
 407                 if(&block==&stage->content)
 408                         iface_insert_point = i;
 409
 410                 (*i)->visit(*this);
 411         }
 412 }
 413
 414 string InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
 415 {
 416         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
 417         return prefix+name.substr(offset);
 418 }
 419
 420 VariableDeclaration *InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
 421 {
 422         if(stage->content.variables.count(name))
 423                 return 0;
 424
 425         VariableDeclaration* iface_var = new VariableDeclaration;
 426         iface_var->sampling = var.sampling;
 427         iface_var->interface = iface;
 428         iface_var->type = var.type;
 429         iface_var->name = name;
 430         /* Geometry shader inputs are always arrays.  But if we're bringing in an
 431         entire block, the array is on the block and not individual variables. */
 432         if(stage->type==Stage::GEOMETRY && !copy_block)
 433                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
 434         else
 435                 iface_var->array = var.array;
 436         if(iface_var->array)
 437                 iface_var->array_size = var.array_size;
 438         if(iface=="in")
 439         {
 440                 iface_var->layout = var.layout;
 441                 iface_var->linked_declaration = &var;
 442                 var.linked_declaration = iface_var;
 443         }
 444
 445         iface_target_block->body.insert(iface_insert_point, iface_var);
 446         iface_target_block->variables.insert(make_pair(name, iface_var));
 447
 448         return iface_var;
 449 }
 450
 451 InterfaceBlock *InterfaceGenerator::generate_interface(InterfaceBlock &out_block)
 452 {
 453         if(stage->interface_blocks.count("in"+out_block.name))
 454                 return 0;
 455
 456         InterfaceBlock *in_block = new InterfaceBlock;
 457         in_block->interface = "in";
 458         in_block->name = out_block.name;
 459         in_block->instance_name = out_block.instance_name;
 460         if(stage->type==Stage::GEOMETRY)
 461                 in_block->array = true;
 462         else
 463                 in_block->array = out_block.array;
 464         in_block->linked_block = &out_block;
 465         out_block.linked_block = in_block;
 466
 467         {
 468                 SetFlag set_copy(copy_block, true);
 469                 SetForScope<Block *> set_target(iface_target_block, &in_block->members);
 470                 SetForScope<NodeList<Statement>::iterator> set_ins_pt(iface_insert_point, in_block->members.body.end());
 471                 out_block.members.visit(*this);
 472         }
 473
 474         iface_target_block->body.insert(iface_insert_point, in_block);
 475         stage->interface_blocks.insert(make_pair("in"+in_block->name, in_block));
 476         if(!in_block->instance_name.empty())
 477                 stage->interface_blocks.insert(make_pair("_"+in_block->instance_name, in_block));
 478
 479         SetFlag set_scope(function_scope, false);
 480         SetForScope<Block *> set_block(current_block, &stage->content);
 481         in_block->visit(*this);
 482
 483         return in_block;
 484 }
 485
 486 ExpressionStatement &InterfaceGenerator::insert_assignment(const string &left, Expression *right)
 487 {
 488         Assignment *assign = new Assignment;
 489         VariableReference *ref = new VariableReference;
 490         ref->name = left;
 491         assign->left = ref;
 492         assign->oper = &Operator::get_operator("=", Operator::BINARY);
 493         assign->right = right;
 494
 495         ExpressionStatement *stmt = new ExpressionStatement;
 496         stmt->expression = assign;
 497         current_block->body.insert(assignment_insert_point, stmt);
 498         stmt->visit(*this);
 499
 500         return *stmt;
 501 }
 502
 503 void InterfaceGenerator::visit(VariableReference &var)
 504 {
 505         if(var.declaration || !stage->previous)
 506                 return;
 507         /* Don't pull a variable from previous stage if we just generated an output
 508         interface in this stage */
 509         if(stage->content.variables.count(var.name))
 510                 return;
 511
 512         const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
 513         map<string, VariableDeclaration *>::const_iterator i = prev_vars.find(var.name);
 514         if(i==prev_vars.end() || i->second->interface!="out")
 515                 i = prev_vars.find(in_prefix+var.name);
 516         if(i!=prev_vars.end() && i->second->interface=="out")
 517         {
 518                 generate_interface(*i->second, "in", i->second->name);
 519                 var.name = i->second->name;
 520                 return;
 521         }
 522
 523         const map<string, InterfaceBlock *> &prev_blocks = stage->previous->interface_blocks;
 524         map<string, InterfaceBlock *>::const_iterator j = prev_blocks.find("_"+var.name);
 525         if(j!=prev_blocks.end() && j->second->interface=="out")
 526         {
 527                 generate_interface(*j->second);
 528                 /* Let VariableResolver convert the variable reference into an interface
 529                 block reference. */
 530                 return;
 531         }
 532
 533         for(j=prev_blocks.begin(); j!=prev_blocks.end(); ++j)
 534                 if(j->second->instance_name.empty())
 535                 {
 536                         i = j->second->members.variables.find(var.name);
 537                         if(i!=j->second->members.variables.end())
 538                         {
 539                                 generate_interface(*j->second);
 540                                 return;
 541                         }
 542                 }
 543 }
 544
 545 void InterfaceGenerator::visit(VariableDeclaration &var)
 546 {
 547         if(copy_block)
 548         {
 549                 generate_interface(var, "in", var.name);
 550                 return;
 551         }
 552
 553         if(iface_block)
 554         {
 555                 if(iface_block->linked_block)
 556                 {
 557                         // Link all variables to their counterparts in the linked block.
 558                         const map<string, VariableDeclaration *> &linked_vars = iface_block->linked_block->members.variables;
 559                         map<string, VariableDeclaration *>::const_iterator i = linked_vars.find(var.name);
 560                         if(i!=linked_vars.end())
 561                                 var.linked_declaration = i->second;
 562                 }
 563                 return;
 564         }
 565
 566         if(var.interface=="out")
 567         {
 568                 /* For output variables in function scope, generate a global interface
 569                 and replace the local declaration with an assignment. */
 570                 VariableDeclaration *out_var = 0;
 571                 if(function_scope && (out_var=generate_interface(var, "out", var.name)))
 572                 {
 573                         out_var->source = var.source;
 574                         out_var->line = var.line;
 575                         nodes_to_remove.insert(&var);
 576                         if(var.init_expression)
 577                         {
 578                                 ExpressionStatement &stmt = insert_assignment(var.name, var.init_expression->clone());
 579                                 stmt.source = var.source;
 580                                 stmt.line = var.line;
 581                                 return;
 582                         }
 583                 }
 584         }
 585         else if(var.interface=="in")
 586         {
 587                 /* Try to link input variables in global scope with output variables from
 588                 previous stage. */
 589                 if(current_block==&stage->content && !var.linked_declaration && stage->previous)
 590                 {
 591                         const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
 592                         map<string, VariableDeclaration *>::const_iterator i = prev_vars.find(var.name);
 593                         if(i!=prev_vars.end() && i->second->interface=="out")
 594                         {
 595                                 var.linked_declaration = i->second;
 596                                 i->second->linked_declaration = &var;
 597                         }
 598                 }
 599         }
 600
 601         TraversingVisitor::visit(var);
 602 }
 603
 604 void InterfaceGenerator::visit(InterfaceBlock &iface)
 605 {
 606         if(iface.interface=="in")
 607         {
 608                 /* Try to link input blocks with output blocks sharing the same block
 609                 name from previous stage. */
 610                 if(!iface.linked_block && stage->previous)
 611                 {
 612                         const map<string, InterfaceBlock *> &prev_blocks = stage->previous->interface_blocks;
 613                         map<string, InterfaceBlock *>::const_iterator i = prev_blocks.find("out"+iface.name);
 614                         if(i!=prev_blocks.end())
 615                         {
 616                                 iface.linked_block = i->second;
 617                                 i->second->linked_block = &iface;
 618                         }
 619                 }
 620         }
 621
 622         SetForScope<InterfaceBlock *> set_iface(iface_block, &iface);
 623         TraversingVisitor::visit(iface);
 624 }
 625
 626 void InterfaceGenerator::visit(FunctionDeclaration &func)
 627 {
 628         SetFlag set_scope(function_scope, true);
 629         // Skip parameters because they're not useful here
 630         func.body.visit(*this);
 631 }
 632
 633 void InterfaceGenerator::visit(Passthrough &pass)
 634 {
 635         vector<VariableDeclaration *> pass_vars;
 636
 637         // Pass through all input variables of this stage.
 638         for(map<string, VariableDeclaration *>::const_iterator i=stage->content.variables.begin(); i!=stage->content.variables.end(); ++i)
 639                 if(i->second->interface=="in")
 640                         pass_vars.push_back(i->second);
 641
 642         if(stage->previous)
 643         {
 644                 const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
 645                 for(map<string, VariableDeclaration *>::const_iterator i=prev_vars.begin(); i!=prev_vars.end(); ++i)
 646                 {
 647                         if(i->second->interface!="out")
 648                                 continue;
 649
 650                         /* Pass through output variables from the previous stage, but only
 651                         those which are not already linked to an input here. */
 652                         if(!i->second->linked_declaration && generate_interface(*i->second, "in", i->second->name))
 653                                 pass_vars.push_back(i->second);
 654                 }
 655         }
 656
 657         if(stage->type==Stage::GEOMETRY)
 658         {
 659                 /* Special case for geometry shader: copy gl_Position from input to
 660                 output. */
 661                 InterfaceBlockReference *ref = new InterfaceBlockReference;
 662                 ref->name = "gl_in";
 663
 664                 BinaryExpression *subscript = new BinaryExpression;
 665                 subscript->left = ref;
 666                 subscript->oper = &Operator::get_operator("[", Operator::BINARY);
 667                 subscript->right = pass.subscript;
 668
 669                 MemberAccess *memacc = new MemberAccess;
 670                 memacc->left = subscript;
 671                 memacc->member = "gl_Position";
 672
 673                 insert_assignment("gl_Position", memacc);
 674         }
 675
 676         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
 677         {
 678                 string out_name = change_prefix((*i)->name, out_prefix);
 679                 generate_interface(**i, "out", out_name);
 680
 681                 VariableReference *ref = new VariableReference;
 682                 ref->name = (*i)->name;
 683                 if(pass.subscript)
 684                 {
 685                         BinaryExpression *subscript = new BinaryExpression;
 686                         subscript->left = ref;
 687                         subscript->oper = &Operator::get_operator("[", Operator::BINARY);
 688                         subscript->right = pass.subscript;
 689                         insert_assignment(out_name, subscript);
 690                 }
 691                 else
 692                         insert_assignment(out_name, ref);
 693         }
 694
 695         nodes_to_remove.insert(&pass);
 696 }
 697
 698 } // namespace SL
 699 } // namespace GL
 700 } // namespace Msp