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                         {
 103                                 literal->token = (i->second ? "true" : "false");
 104                                 literal->value = static_cast<bool>(i->second);
 105                         }
 106                         else if(var.type=="int")
 107                         {
 108                                 literal->token = lexical_cast<string>(i->second);
 109                                 literal->value = i->second;
 110                         }
 111                         var.init_expression = literal;
 112                 }
 113         }
 114 }
 115
 116
 117 void BlockHierarchyResolver::enter(Block &block)
 118 {
 119         block.parent = current_block;
 120 }
 121
 122
 123 TypeResolver::TypeResolver():
 124         stage(0)
 125 { }
 126
 127 void TypeResolver::apply(Stage &s)
 128 {
 129         stage = &s;
 130         s.types.clear();
 131         s.content.visit(*this);
 132 }
 133
 134 TypeDeclaration *TypeResolver::resolve_type(const string &name)
 135 {
 136         map<string, TypeDeclaration *>::iterator i = stage->types.find(name);
 137         if(i!=stage->types.end())
 138         {
 139                 map<TypeDeclaration *, TypeDeclaration *>::iterator j = alias_map.find(i->second);
 140                 return (j!=alias_map.end() ? j->second : i->second);
 141         }
 142         else
 143                 return 0;
 144 }
 145
 146 void TypeResolver::visit(Block &block)
 147 {
 148         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 149         {
 150                 if(!block.parent)
 151                         type_insert_point = i;
 152                 (*i)->visit(*this);
 153         }
 154 }
 155
 156 void TypeResolver::visit(BasicTypeDeclaration &type)
 157 {
 158         type.base_type = resolve_type(type.base);
 159
 160         if(type.kind==BasicTypeDeclaration::VECTOR && type.base_type)
 161                 if(BasicTypeDeclaration *basic_base = dynamic_cast<BasicTypeDeclaration *>(type.base_type))
 162                         if(basic_base->kind==BasicTypeDeclaration::VECTOR)
 163                         {
 164                                 type.kind = BasicTypeDeclaration::MATRIX;
 165                                 type.size |= basic_base->size<<16;
 166                         }
 167
 168         if(type.kind==BasicTypeDeclaration::ALIAS && type.base_type)
 169                 alias_map[&type] = type.base_type;
 170         else if(type.kind==BasicTypeDeclaration::ARRAY && type.base_type)
 171                 array_types[type.base_type] = &type;
 172
 173         stage->types.insert(make_pair(type.name, &type));
 174 }
 175
 176 void TypeResolver::visit(ImageTypeDeclaration &type)
 177 {
 178         type.base_type = resolve_type(type.base);
 179         stage->types.insert(make_pair(type.name, &type));
 180 }
 181
 182 void TypeResolver::visit(StructDeclaration &strct)
 183 {
 184         stage->types.insert(make_pair(strct.name, &strct));
 185         TraversingVisitor::visit(strct);
 186 }
 187
 188 void TypeResolver::visit(VariableDeclaration &var)
 189 {
 190         TypeDeclaration *type = resolve_type(var.type);
 191         if(var.array && type)
 192         {
 193                 map<TypeDeclaration *, TypeDeclaration *>::iterator i = array_types.find(type);
 194                 if(i==array_types.end())
 195                 {
 196                         BasicTypeDeclaration *array = new BasicTypeDeclaration;
 197                         array->source = BUILTIN_SOURCE;
 198                         array->name = type->name+"[]";
 199                         array->kind = BasicTypeDeclaration::ARRAY;
 200                         array->base = type->name;
 201                         array->base_type = type;
 202                         stage->content.body.insert(type_insert_point, array);
 203                         array->visit(*this);
 204                         type = array;
 205                 }
 206                 else
 207                         type = i->second;
 208         }
 209         var.type_declaration = type;
 210 }
 211
 212 void TypeResolver::visit(FunctionDeclaration &func)
 213 {
 214         func.return_type_declaration = resolve_type(func.return_type);
 215         TraversingVisitor::visit(func);
 216 }
 217
 218
 219 VariableResolver::VariableResolver():
 220         stage(0),
 221         r_any_resolved(false),
 222         record_target(false),
 223         r_self_referencing(false),
 224         r_assignment_target(0)
 225 { }
 226
 227 bool VariableResolver::apply(Stage &s)
 228 {
 229         stage = &s;
 230         s.interface_blocks.clear();
 231         r_any_resolved = false;
 232         s.content.visit(*this);
 233         return r_any_resolved;
 234 }
 235
 236 void VariableResolver::enter(Block &block)
 237 {
 238         block.variables.clear();
 239 }
 240
 241 void VariableResolver::visit(VariableReference &var)
 242 {
 243         VariableDeclaration *declaration = 0;
 244
 245         /* Look for variable declarations in the block hierarchy first.  Interface
 246         blocks are always defined in the top level so we can't accidentally skip
 247         one. */
 248         for(Block *block=current_block; (!declaration && block); block=block->parent)
 249         {
 250                 map<string, VariableDeclaration *>::iterator i = block->variables.find(var.name);
 251                 if(i!=block->variables.end())
 252                         declaration = i->second;
 253         }
 254
 255         if(!declaration)
 256         {
 257                 const map<string, InterfaceBlock *> &blocks = stage->interface_blocks;
 258                 map<string, InterfaceBlock *>::const_iterator i = blocks.find("_"+var.name);
 259                 if(i!=blocks.end())
 260                 {
 261                         /* The name refers to an interface block with an instance name rather
 262                         than a variable.  Prepare a new syntax tree node accordingly. */
 263                         r_iface_ref = new InterfaceBlockReference;
 264                         r_iface_ref->source = var.source;
 265                         r_iface_ref->line = var.line;
 266                         r_iface_ref->name = var.name;
 267                         r_iface_ref->declaration = i->second;
 268                 }
 269                 else
 270                 {
 271                         // Look for the variable in anonymous interface blocks.
 272                         for(i=blocks.begin(); (!declaration && i!=blocks.end()); ++i)
 273                                 if(i->second->instance_name.empty())
 274                                 {
 275                                         map<string, VariableDeclaration *>::iterator j = i->second->members.variables.find(var.name);
 276                                         if(j!=i->second->members.variables.end())
 277                                                 declaration = j->second;
 278                                 }
 279                 }
 280         }
 281
 282         r_any_resolved |= (declaration!=var.declaration);
 283         var.declaration = declaration;
 284
 285         if(record_target)
 286         {
 287                 if(r_assignment_target)
 288                 {
 289                         /* More than one variable reference found in assignment target.
 290                         Unable to determine what the primary target is. */
 291                         record_target = false;
 292                         r_assignment_target = 0;
 293                 }
 294                 else
 295                         r_assignment_target = var.declaration;
 296         }
 297         else if(var.declaration && var.declaration==r_assignment_target)
 298                 r_self_referencing = true;
 299 }
 300
 301 void VariableResolver::visit(InterfaceBlockReference &iface)
 302 {
 303         map<string, InterfaceBlock *>::iterator i = stage->interface_blocks.find("_"+iface.name);
 304         InterfaceBlock *declaration = (i!=stage->interface_blocks.end() ? i->second : 0);
 305         r_any_resolved |= (declaration!=iface.declaration);
 306         iface.declaration = declaration;
 307 }
 308
 309 void VariableResolver::visit(MemberAccess &memacc)
 310 {
 311         r_iface_ref = 0;
 312         memacc.left->visit(*this);
 313         if(r_iface_ref)
 314                 memacc.left = r_iface_ref;
 315         r_iface_ref = 0;
 316
 317         map<string, VariableDeclaration *> *members = 0;
 318         if(StructDeclaration *strct = dynamic_cast<StructDeclaration *>(memacc.left->type))
 319                 members = &strct->members.variables;
 320         else if(InterfaceBlockReference *iface_ref = dynamic_cast<InterfaceBlockReference *>(memacc.left.get()))
 321         {
 322                 if(iface_ref->declaration)
 323                         members = &iface_ref->declaration->members.variables;
 324         }
 325
 326         VariableDeclaration *declaration = 0;
 327         if(members)
 328         {
 329                 map<string, VariableDeclaration *>::iterator i = members->find(memacc.member);
 330                 if(i!=members->end())
 331                         declaration = i->second;
 332         }
 333
 334         r_any_resolved |= (declaration!=memacc.declaration);
 335         memacc.declaration = declaration;
 336 }
 337
 338 void VariableResolver::visit(UnaryExpression &unary)
 339 {
 340         TraversingVisitor::visit(unary);
 341         r_iface_ref = 0;
 342 }
 343
 344 void VariableResolver::visit(BinaryExpression &binary)
 345 {
 346         if(binary.oper->token[0]=='[')
 347         {
 348                 {
 349                         /* The subscript expression is not a part of the primary assignment
 350                         target. */
 351                         SetFlag set(record_target, false);
 352                         binary.right->visit(*this);
 353                 }
 354                 r_iface_ref = 0;
 355                 binary.left->visit(*this);
 356                 if(r_iface_ref)
 357                         binary.left = r_iface_ref;
 358         }
 359         else
 360                 TraversingVisitor::visit(binary);
 361
 362         r_iface_ref = 0;
 363 }
 364
 365 void VariableResolver::visit(Assignment &assign)
 366 {
 367         {
 368                 SetFlag set(record_target);
 369                 r_assignment_target = 0;
 370                 assign.left->visit(*this);
 371                 r_any_resolved |= (r_assignment_target!=assign.target_declaration);
 372                 assign.target_declaration = r_assignment_target;
 373         }
 374
 375         r_self_referencing = false;
 376         assign.right->visit(*this);
 377         assign.self_referencing = (r_self_referencing || assign.oper->token[0]!='=');
 378
 379         r_iface_ref = 0;
 380 }
 381
 382 void VariableResolver::visit(FunctionCall &call)
 383 {
 384         TraversingVisitor::visit(call);
 385         r_iface_ref = 0;
 386 }
 387
 388 void VariableResolver::visit(VariableDeclaration &var)
 389 {
 390         if(!block_interface.empty() && var.interface.empty())
 391                 var.interface = block_interface;
 392
 393         TraversingVisitor::visit(var);
 394         current_block->variables.insert(make_pair(var.name, &var));
 395 }
 396
 397 void VariableResolver::visit(InterfaceBlock &iface)
 398 {
 399         /* Block names can be reused in different interfaces.  Prefix the name with
 400         the first character of the interface to avoid conflicts. */
 401         stage->interface_blocks.insert(make_pair(iface.interface+iface.name, &iface));
 402         if(!iface.instance_name.empty())
 403                 stage->interface_blocks.insert(make_pair("_"+iface.instance_name, &iface));
 404
 405         SetForScope<string> set_iface(block_interface, iface.interface);
 406         TraversingVisitor::visit(iface);
 407 }
 408
 409
 410 ExpressionResolver::ExpressionResolver():
 411         stage(0),
 412         r_any_resolved(false)
 413 { }
 414
 415 bool ExpressionResolver::apply(Stage &s)
 416 {
 417         stage = &s;
 418         r_any_resolved = false;
 419         s.content.visit(*this);
 420         return r_any_resolved;
 421 }
 422
 423 bool ExpressionResolver::is_scalar(BasicTypeDeclaration &type)
 424 {
 425         return (type.kind==BasicTypeDeclaration::INT || type.kind==BasicTypeDeclaration::FLOAT);
 426 }
 427
 428 bool ExpressionResolver::is_vector_or_matrix(BasicTypeDeclaration &type)
 429 {
 430         return (type.kind==BasicTypeDeclaration::VECTOR || type.kind==BasicTypeDeclaration::MATRIX);
 431 }
 432
 433 BasicTypeDeclaration *ExpressionResolver::get_element_type(BasicTypeDeclaration &type)
 434 {
 435         if(is_vector_or_matrix(type) || type.kind==BasicTypeDeclaration::ARRAY)
 436         {
 437                 BasicTypeDeclaration *basic_base = dynamic_cast<BasicTypeDeclaration *>(type.base_type);
 438                 return (basic_base ? get_element_type(*basic_base) : 0);
 439         }
 440         else
 441                 return &type;
 442 }
 443
 444 bool ExpressionResolver::can_convert(BasicTypeDeclaration &from, BasicTypeDeclaration &to)
 445 {
 446         if(from.kind==BasicTypeDeclaration::INT && to.kind==BasicTypeDeclaration::FLOAT)
 447                 return from.size<=to.size;
 448         else if(from.kind!=to.kind)
 449                 return false;
 450         else if((from.kind==BasicTypeDeclaration::VECTOR || from.kind==BasicTypeDeclaration::MATRIX) && from.size==to.size)
 451         {
 452                 BasicTypeDeclaration *from_base = dynamic_cast<BasicTypeDeclaration *>(from.base_type);
 453                 BasicTypeDeclaration *to_base = dynamic_cast<BasicTypeDeclaration *>(to.base_type);
 454                 return (from_base && to_base && can_convert(*from_base, *to_base));
 455         }
 456         else
 457                 return false;
 458 }
 459
 460 ExpressionResolver::Compatibility ExpressionResolver::get_compatibility(BasicTypeDeclaration &left, BasicTypeDeclaration &right)
 461 {
 462         if(&left==&right)
 463                 return SAME_TYPE;
 464         else if(can_convert(left, right))
 465                 return LEFT_CONVERTIBLE;
 466         else if(can_convert(right, left))
 467                 return RIGHT_CONVERTIBLE;
 468         else
 469                 return NOT_COMPATIBLE;
 470 }
 471
 472 BasicTypeDeclaration *ExpressionResolver::find_type(BasicTypeDeclaration::Kind kind, unsigned size)
 473 {
 474         for(vector<BasicTypeDeclaration *>::const_iterator i=basic_types.begin(); i!=basic_types.end(); ++i)
 475                 if((*i)->kind==kind && (*i)->size==size)
 476                         return *i;
 477         return 0;
 478 }
 479
 480 BasicTypeDeclaration *ExpressionResolver::find_type(BasicTypeDeclaration &elem_type, BasicTypeDeclaration::Kind kind, unsigned size)
 481 {
 482         for(vector<BasicTypeDeclaration *>::const_iterator i=basic_types.begin(); i!=basic_types.end(); ++i)
 483                 if(get_element_type(**i)==&elem_type && (*i)->kind==kind && (*i)->size==size)
 484                         return *i;
 485         return 0;
 486 }
 487
 488 void ExpressionResolver::convert_to(RefPtr<Expression> &expr, BasicTypeDeclaration &type)
 489 {
 490         RefPtr<FunctionCall> call = new FunctionCall;
 491         call->name = type.name;
 492         call->constructor = true;
 493         call->arguments.push_back(0);
 494         call->arguments.back() = expr;
 495         call->type = &type;
 496         expr = call;
 497 }
 498
 499 bool ExpressionResolver::convert_to_element(RefPtr<Expression> &expr, BasicTypeDeclaration &elem_type)
 500 {
 501         if(BasicTypeDeclaration *expr_type = dynamic_cast<BasicTypeDeclaration *>(expr->type))
 502         {
 503                 BasicTypeDeclaration *to_type = &elem_type;
 504                 if(is_vector_or_matrix(*expr_type))
 505                         to_type = find_type(elem_type, expr_type->kind, expr_type->size);
 506                 if(to_type)
 507                 {
 508                         convert_to(expr, *to_type);
 509                         return true;
 510                 }
 511         }
 512
 513         return false;
 514 }
 515
 516 void ExpressionResolver::resolve(Expression &expr, TypeDeclaration *type, bool lvalue)
 517 {
 518         r_any_resolved |= (type!=expr.type || lvalue!=expr.lvalue);
 519         expr.type = type;
 520         expr.lvalue = lvalue;
 521 }
 522
 523 void ExpressionResolver::visit(Literal &literal)
 524 {
 525         if(literal.value.check_type<bool>())
 526                 resolve(literal, find_type(BasicTypeDeclaration::BOOL, 1), false);
 527         else if(literal.value.check_type<int>())
 528                 resolve(literal, find_type(BasicTypeDeclaration::INT, 32), false);
 529         else if(literal.value.check_type<float>())
 530                 resolve(literal, find_type(BasicTypeDeclaration::FLOAT, 32), false);
 531 }
 532
 533 void ExpressionResolver::visit(ParenthesizedExpression &parexpr)
 534 {
 535         TraversingVisitor::visit(parexpr);
 536         resolve(parexpr, parexpr.expression->type, parexpr.expression->lvalue);
 537 }
 538
 539 void ExpressionResolver::visit(VariableReference &var)
 540 {
 541         if(var.declaration)
 542                 resolve(var, var.declaration->type_declaration, true);
 543 }
 544
 545 void ExpressionResolver::visit(InterfaceBlockReference &iface)
 546 {
 547         resolve(iface, 0, true);
 548 }
 549
 550 void ExpressionResolver::visit(MemberAccess &memacc)
 551 {
 552         TraversingVisitor::visit(memacc);
 553
 554         if(memacc.declaration)
 555                 resolve(memacc, memacc.declaration->type_declaration, memacc.left->lvalue);
 556 }
 557
 558 void ExpressionResolver::visit(UnaryExpression &unary)
 559 {
 560         TraversingVisitor::visit(unary);
 561
 562         BasicTypeDeclaration *basic = dynamic_cast<BasicTypeDeclaration *>(unary.expression->type);
 563         if(!basic)
 564                 return;
 565
 566         char oper = unary.oper->token[0];
 567         if(oper=='!')
 568         {
 569                 if(basic->kind!=BasicTypeDeclaration::BOOL)
 570                         return;
 571         }
 572         else if(oper=='~')
 573         {
 574                 if(basic->kind!=BasicTypeDeclaration::INT)
 575                         return;
 576         }
 577         else if(oper=='+' || oper=='-')
 578         {
 579                 BasicTypeDeclaration *elem = get_element_type(*basic);
 580                 if(!elem || !is_scalar(*elem))
 581                         return;
 582         }
 583         resolve(unary, basic, unary.expression->lvalue);
 584 }
 585
 586 void ExpressionResolver::visit(BinaryExpression &binary)
 587 {
 588         TraversingVisitor::visit(binary);
 589
 590         /* Binary operators are only defined for basic types (not for image or
 591         structure types). */
 592         BasicTypeDeclaration *basic_left = dynamic_cast<BasicTypeDeclaration *>(binary.left->type);
 593         BasicTypeDeclaration *basic_right = dynamic_cast<BasicTypeDeclaration *>(binary.right->type);
 594         if(!basic_left || !basic_right)
 595                 return;
 596
 597         char oper = binary.oper->token[0];
 598         if(oper=='[')
 599         {
 600                 /* Subscripting operates on vectors, matrices and arrays, and the right
 601                 operand must be an integer. */
 602                 if((!is_vector_or_matrix(*basic_left) && basic_left->kind!=BasicTypeDeclaration::ARRAY) || basic_right->kind!=BasicTypeDeclaration::INT)
 603                         return;
 604
 605                 resolve(binary, basic_left->base_type, binary.left->lvalue);
 606                 return;
 607         }
 608         else if(basic_left->kind==BasicTypeDeclaration::ARRAY || basic_right->kind==BasicTypeDeclaration::ARRAY)
 609                 // No other binary operator can be used with arrays.
 610                 return;
 611
 612         BasicTypeDeclaration *elem_left = get_element_type(*basic_left);
 613         BasicTypeDeclaration *elem_right = get_element_type(*basic_right);
 614         if(!elem_left || !elem_right)
 615                 return;
 616
 617         Compatibility compat = get_compatibility(*basic_left, *basic_right);
 618         Compatibility elem_compat = get_compatibility(*elem_left, *elem_right);
 619         if(elem_compat==NOT_COMPATIBLE)
 620                 return;
 621
 622         TypeDeclaration *type = 0;
 623         char oper2 = binary.oper->token[1];
 624         if((oper=='<' && oper2!='<') || (oper=='>' && oper2!='>'))
 625         {
 626                 /* Relational operators compare two scalar integer or floating-point
 627                 values. */
 628                 if(!is_scalar(*elem_left) || !is_scalar(*elem_right) || compat==NOT_COMPATIBLE)
 629                         return;
 630
 631                 type = find_type(BasicTypeDeclaration::BOOL, 1);
 632         }
 633         else if((oper=='=' || oper=='!') && oper2=='=')
 634         {
 635                 // Equality comparison can be done on any compatible types.
 636                 if(compat==NOT_COMPATIBLE)
 637                         return;
 638
 639                 type = find_type(BasicTypeDeclaration::BOOL, 1);
 640         }
 641         else if(oper2=='&' || oper2=='|' || oper2=='^')
 642         {
 643                 // Logical operators can only be applied to booleans.
 644                 if(basic_left->kind!=BasicTypeDeclaration::BOOL || basic_right->kind!=BasicTypeDeclaration::BOOL)
 645                         return;
 646
 647                 type = basic_left;
 648         }
 649         else if((oper=='&' || oper=='|' || oper=='^' || oper=='%') && !oper2)
 650         {
 651                 // Bitwise operators and modulo can only be applied to integers.
 652                 if(basic_left->kind!=BasicTypeDeclaration::INT || basic_right->kind!=BasicTypeDeclaration::INT)
 653                         return;
 654
 655                 type = (compat==LEFT_CONVERTIBLE ? basic_right : basic_left);
 656         }
 657         else if((oper=='<' || oper=='>') && oper2==oper)
 658         {
 659                 // Shifts only apply to integers.
 660                 if(basic_left->kind!=BasicTypeDeclaration::INT || basic_right->kind!=BasicTypeDeclaration::INT)
 661                         return;
 662
 663                 type = basic_left;
 664         }
 665         else if(oper=='+' || oper=='-' || oper=='*' || oper=='/')
 666         {
 667                 // Arithmetic operators require scalar elements.
 668                 if(!is_scalar(*elem_left) || !is_scalar(*elem_right))
 669                         return;
 670
 671                 if(oper=='*' && is_vector_or_matrix(*basic_left) && is_vector_or_matrix(*basic_right) &&
 672                         (basic_left->kind==BasicTypeDeclaration::MATRIX || basic_right->kind==BasicTypeDeclaration::MATRIX))
 673                 {
 674                         /* Multiplication has special rules when at least one operand is a
 675                         matrix and the other is a vector or a matrix. */
 676                         unsigned left_columns = basic_left->size&0xFFFF;
 677                         unsigned right_rows = basic_right->size;
 678                         if(basic_right->kind==BasicTypeDeclaration::MATRIX)
 679                                 right_rows >>= 16;
 680                         if(left_columns!=right_rows)
 681                                 return;
 682
 683                         BasicTypeDeclaration *elem_result = (elem_compat==LEFT_CONVERTIBLE ? elem_right : elem_left);
 684
 685                         if(basic_left->kind==BasicTypeDeclaration::VECTOR)
 686                                 type = find_type(*elem_result, BasicTypeDeclaration::VECTOR, basic_right->size&0xFFFF);
 687                         else if(basic_right->kind==BasicTypeDeclaration::VECTOR)
 688                                 type = find_type(*elem_result, BasicTypeDeclaration::VECTOR, basic_left->size>>16);
 689                         else
 690                                 type = find_type(*elem_result, BasicTypeDeclaration::MATRIX, (basic_left->size&0xFFFF0000)|(basic_right->size&0xFFFF));
 691                 }
 692                 else if(compat==NOT_COMPATIBLE)
 693                 {
 694                         // Arithmetic between scalars and matrices or vectors is supported.
 695                         if(is_scalar(*basic_left) && is_vector_or_matrix(*basic_right))
 696                                 type = (elem_compat==RIGHT_CONVERTIBLE ? find_type(*elem_left, basic_right->kind, basic_right->size) : basic_right);
 697                         else if(is_vector_or_matrix(*basic_left) && is_scalar(*basic_right))
 698                                 type = (elem_compat==LEFT_CONVERTIBLE ? find_type(*elem_right, basic_left->kind, basic_left->size) : basic_left);
 699                         else
 700                                 return;
 701                 }
 702                 else if(compat==LEFT_CONVERTIBLE)
 703                         type = basic_right;
 704                 else
 705                         type = basic_left;
 706         }
 707         else
 708                 return;
 709
 710         bool converted = true;
 711         if(compat==LEFT_CONVERTIBLE)
 712                 convert_to(binary.left, *basic_right);
 713         else if(compat==RIGHT_CONVERTIBLE)
 714                 convert_to(binary.right, *basic_left);
 715         else if(elem_compat==LEFT_CONVERTIBLE)
 716                 converted = convert_to_element(binary.left, *elem_right);
 717         else if(elem_compat==RIGHT_CONVERTIBLE)
 718                 converted = convert_to_element(binary.right, *elem_left);
 719
 720         if(!converted)
 721                 type = 0;
 722
 723         resolve(binary, type, false);
 724 }
 725
 726 void ExpressionResolver::visit(Assignment &assign)
 727 {
 728         TraversingVisitor::visit(assign);
 729         resolve(assign, assign.left->type, true);
 730 }
 731
 732 void ExpressionResolver::visit(FunctionCall &call)
 733 {
 734         TraversingVisitor::visit(call);
 735
 736         TypeDeclaration *type = 0;
 737         if(call.declaration)
 738                 type = call.declaration->return_type_declaration;
 739         else if(call.constructor)
 740         {
 741                 map<string, TypeDeclaration *>::const_iterator i=stage->types.find(call.name);
 742                 type = (i!=stage->types.end() ? i->second : 0);
 743         }
 744         resolve(call, type, false);
 745 }
 746
 747 void ExpressionResolver::visit(BasicTypeDeclaration &type)
 748 {
 749         basic_types.push_back(&type);
 750 }
 751
 752 void ExpressionResolver::visit(VariableDeclaration &var)
 753 {
 754         TraversingVisitor::visit(var);
 755         if(!var.init_expression)
 756                 return;
 757
 758         BasicTypeDeclaration *var_basic = dynamic_cast<BasicTypeDeclaration *>(var.type_declaration);
 759         BasicTypeDeclaration *init_basic = dynamic_cast<BasicTypeDeclaration *>(var.init_expression->type);
 760         if(!var_basic || !init_basic)
 761                 return;
 762
 763         Compatibility compat = get_compatibility(*var_basic, *init_basic);
 764         if(compat==RIGHT_CONVERTIBLE)
 765                 convert_to(var.init_expression, *var_basic);
 766 }
 767
 768
 769 void FunctionResolver::apply(Stage &s)
 770 {
 771         stage = &s;
 772         s.functions.clear();
 773         s.content.visit(*this);
 774 }
 775
 776 void FunctionResolver::visit(FunctionCall &call)
 777 {
 778         map<string, FunctionDeclaration *>::iterator i = stage->functions.find(call.name);
 779         if(i!=stage->functions.end())
 780                 call.declaration = i->second;
 781
 782         TraversingVisitor::visit(call);
 783 }
 784
 785 void FunctionResolver::visit(FunctionDeclaration &func)
 786 {
 787         FunctionDeclaration *&stage_decl = stage->functions[func.name];
 788         vector<FunctionDeclaration *> &decls = declarations[func.name];
 789         if(func.definition==&func)
 790         {
 791                 stage_decl = &func;
 792
 793                 // Set all previous declarations to use this definition.
 794                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 795                 {
 796                         (*i)->definition = func.definition;
 797                         (*i)->body.body.clear();
 798                 }
 799         }
 800         else
 801         {
 802                 func.definition = 0;
 803                 if(!stage_decl)
 804                         stage_decl = &func;
 805                 else
 806                         func.definition = stage_decl->definition;
 807         }
 808         decls.push_back(&func);
 809
 810         TraversingVisitor::visit(func);
 811 }
 812
 813
 814 InterfaceGenerator::InterfaceGenerator():
 815         stage(0),
 816         function_scope(false),
 817         iface_block(0),
 818         copy_block(false),
 819         iface_target_block(0)
 820 { }
 821
 822 string InterfaceGenerator::get_out_prefix(Stage::Type type)
 823 {
 824         if(type==Stage::VERTEX)
 825                 return "_vs_out_";
 826         else if(type==Stage::GEOMETRY)
 827                 return "_gs_out_";
 828         else
 829                 return string();
 830 }
 831
 832 void InterfaceGenerator::apply(Stage &s)
 833 {
 834         stage = &s;
 835         iface_target_block = &stage->content;
 836         if(stage->previous)
 837                 in_prefix = get_out_prefix(stage->previous->type);
 838         out_prefix = get_out_prefix(stage->type);
 839         s.content.visit(*this);
 840         NodeRemover().apply(s, nodes_to_remove);
 841 }
 842
 843 void InterfaceGenerator::visit(Block &block)
 844 {
 845         SetForScope<Block *> set_block(current_block, &block);
 846         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 847         {
 848                 assignment_insert_point = i;
 849                 if(&block==&stage->content)
 850                         iface_insert_point = i;
 851
 852                 (*i)->visit(*this);
 853         }
 854 }
 855
 856 string InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
 857 {
 858         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
 859         return prefix+name.substr(offset);
 860 }
 861
 862 VariableDeclaration *InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
 863 {
 864         if(stage->content.variables.count(name))
 865                 return 0;
 866
 867         VariableDeclaration* iface_var = new VariableDeclaration;
 868         iface_var->sampling = var.sampling;
 869         iface_var->interface = iface;
 870         iface_var->type = var.type;
 871         iface_var->name = name;
 872         /* Geometry shader inputs are always arrays.  But if we're bringing in an
 873         entire block, the array is on the block and not individual variables. */
 874         if(stage->type==Stage::GEOMETRY && !copy_block)
 875                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
 876         else
 877                 iface_var->array = var.array;
 878         if(iface_var->array)
 879                 iface_var->array_size = var.array_size;
 880         if(iface=="in")
 881         {
 882                 iface_var->layout = var.layout;
 883                 iface_var->linked_declaration = &var;
 884                 var.linked_declaration = iface_var;
 885         }
 886
 887         iface_target_block->body.insert(iface_insert_point, iface_var);
 888         iface_target_block->variables.insert(make_pair(name, iface_var));
 889
 890         return iface_var;
 891 }
 892
 893 InterfaceBlock *InterfaceGenerator::generate_interface(InterfaceBlock &out_block)
 894 {
 895         if(stage->interface_blocks.count("in"+out_block.name))
 896                 return 0;
 897
 898         InterfaceBlock *in_block = new InterfaceBlock;
 899         in_block->interface = "in";
 900         in_block->name = out_block.name;
 901         in_block->instance_name = out_block.instance_name;
 902         if(stage->type==Stage::GEOMETRY)
 903                 in_block->array = true;
 904         else
 905                 in_block->array = out_block.array;
 906         in_block->linked_block = &out_block;
 907         out_block.linked_block = in_block;
 908
 909         {
 910                 SetFlag set_copy(copy_block, true);
 911                 SetForScope<Block *> set_target(iface_target_block, &in_block->members);
 912                 SetForScope<NodeList<Statement>::iterator> set_ins_pt(iface_insert_point, in_block->members.body.end());
 913                 out_block.members.visit(*this);
 914         }
 915
 916         iface_target_block->body.insert(iface_insert_point, in_block);
 917         stage->interface_blocks.insert(make_pair("in"+in_block->name, in_block));
 918         if(!in_block->instance_name.empty())
 919                 stage->interface_blocks.insert(make_pair("_"+in_block->instance_name, in_block));
 920
 921         SetFlag set_scope(function_scope, false);
 922         SetForScope<Block *> set_block(current_block, &stage->content);
 923         in_block->visit(*this);
 924
 925         return in_block;
 926 }
 927
 928 ExpressionStatement &InterfaceGenerator::insert_assignment(const string &left, Expression *right)
 929 {
 930         Assignment *assign = new Assignment;
 931         VariableReference *ref = new VariableReference;
 932         ref->name = left;
 933         assign->left = ref;
 934         assign->oper = &Operator::get_operator("=", Operator::BINARY);
 935         assign->right = right;
 936
 937         ExpressionStatement *stmt = new ExpressionStatement;
 938         stmt->expression = assign;
 939         current_block->body.insert(assignment_insert_point, stmt);
 940         stmt->visit(*this);
 941
 942         return *stmt;
 943 }
 944
 945 void InterfaceGenerator::visit(VariableReference &var)
 946 {
 947         if(var.declaration || !stage->previous)
 948                 return;
 949         /* Don't pull a variable from previous stage if we just generated an output
 950         interface in this stage */
 951         if(stage->content.variables.count(var.name))
 952                 return;
 953
 954         const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
 955         map<string, VariableDeclaration *>::const_iterator i = prev_vars.find(var.name);
 956         if(i==prev_vars.end() || i->second->interface!="out")
 957                 i = prev_vars.find(in_prefix+var.name);
 958         if(i!=prev_vars.end() && i->second->interface=="out")
 959         {
 960                 generate_interface(*i->second, "in", i->second->name);
 961                 var.name = i->second->name;
 962                 return;
 963         }
 964
 965         const map<string, InterfaceBlock *> &prev_blocks = stage->previous->interface_blocks;
 966         map<string, InterfaceBlock *>::const_iterator j = prev_blocks.find("_"+var.name);
 967         if(j!=prev_blocks.end() && j->second->interface=="out")
 968         {
 969                 generate_interface(*j->second);
 970                 /* Let VariableResolver convert the variable reference into an interface
 971                 block reference. */
 972                 return;
 973         }
 974
 975         for(j=prev_blocks.begin(); j!=prev_blocks.end(); ++j)
 976                 if(j->second->instance_name.empty())
 977                 {
 978                         i = j->second->members.variables.find(var.name);
 979                         if(i!=j->second->members.variables.end())
 980                         {
 981                                 generate_interface(*j->second);
 982                                 return;
 983                         }
 984                 }
 985 }
 986
 987 void InterfaceGenerator::visit(VariableDeclaration &var)
 988 {
 989         if(copy_block)
 990         {
 991                 generate_interface(var, "in", var.name);
 992                 return;
 993         }
 994
 995         if(iface_block)
 996         {
 997                 if(iface_block->linked_block)
 998                 {
 999                         // Link all variables to their counterparts in the linked block.
1000                         const map<string, VariableDeclaration *> &linked_vars = iface_block->linked_block->members.variables;
1001                         map<string, VariableDeclaration *>::const_iterator i = linked_vars.find(var.name);
1002                         if(i!=linked_vars.end())
1003                         {
1004                                 var.linked_declaration = i->second;
1005                                 var.linked_declaration->linked_declaration = &var;
1006                         }
1007                 }
1008                 return;
1009         }
1010
1011         if(var.interface=="out")
1012         {
1013                 /* For output variables in function scope, generate a global interface
1014                 and replace the local declaration with an assignment. */
1015                 VariableDeclaration *out_var = 0;
1016                 if(function_scope && (out_var=generate_interface(var, "out", var.name)))
1017                 {
1018                         out_var->source = var.source;
1019                         out_var->line = var.line;
1020                         nodes_to_remove.insert(&var);
1021                         if(var.init_expression)
1022                         {
1023                                 ExpressionStatement &stmt = insert_assignment(var.name, var.init_expression->clone());
1024                                 stmt.source = var.source;
1025                                 stmt.line = var.line;
1026                                 return;
1027                         }
1028                 }
1029         }
1030         else if(var.interface=="in")
1031         {
1032                 /* Try to link input variables in global scope with output variables from
1033                 previous stage. */
1034                 if(current_block==&stage->content && !var.linked_declaration && stage->previous)
1035                 {
1036                         const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
1037                         map<string, VariableDeclaration *>::const_iterator i = prev_vars.find(var.name);
1038                         if(i!=prev_vars.end() && i->second->interface=="out")
1039                         {
1040                                 var.linked_declaration = i->second;
1041                                 i->second->linked_declaration = &var;
1042                         }
1043                 }
1044         }
1045
1046         TraversingVisitor::visit(var);
1047 }
1048
1049 void InterfaceGenerator::visit(InterfaceBlock &iface)
1050 {
1051         if(iface.interface=="in")
1052         {
1053                 /* Try to link input blocks with output blocks sharing the same block
1054                 name from previous stage. */
1055                 if(!iface.linked_block && stage->previous)
1056                 {
1057                         const map<string, InterfaceBlock *> &prev_blocks = stage->previous->interface_blocks;
1058                         map<string, InterfaceBlock *>::const_iterator i = prev_blocks.find("out"+iface.name);
1059                         if(i!=prev_blocks.end())
1060                         {
1061                                 iface.linked_block = i->second;
1062                                 i->second->linked_block = &iface;
1063                         }
1064                 }
1065         }
1066
1067         SetForScope<InterfaceBlock *> set_iface(iface_block, &iface);
1068         TraversingVisitor::visit(iface);
1069 }
1070
1071 void InterfaceGenerator::visit(FunctionDeclaration &func)
1072 {
1073         SetFlag set_scope(function_scope, true);
1074         // Skip parameters because they're not useful here
1075         func.body.visit(*this);
1076 }
1077
1078 void InterfaceGenerator::visit(Passthrough &pass)
1079 {
1080         vector<VariableDeclaration *> pass_vars;
1081
1082         // Pass through all input variables of this stage.
1083         for(map<string, VariableDeclaration *>::const_iterator i=stage->content.variables.begin(); i!=stage->content.variables.end(); ++i)
1084                 if(i->second->interface=="in")
1085                         pass_vars.push_back(i->second);
1086
1087         if(stage->previous)
1088         {
1089                 const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
1090                 for(map<string, VariableDeclaration *>::const_iterator i=prev_vars.begin(); i!=prev_vars.end(); ++i)
1091                 {
1092                         if(i->second->interface!="out")
1093                                 continue;
1094
1095                         /* Pass through output variables from the previous stage, but only
1096                         those which are not already linked to an input here. */
1097                         if(!i->second->linked_declaration && generate_interface(*i->second, "in", i->second->name))
1098                                 pass_vars.push_back(i->second);
1099                 }
1100         }
1101
1102         if(stage->type==Stage::GEOMETRY)
1103         {
1104                 /* Special case for geometry shader: copy gl_Position from input to
1105                 output. */
1106                 InterfaceBlockReference *ref = new InterfaceBlockReference;
1107                 ref->name = "gl_in";
1108
1109                 BinaryExpression *subscript = new BinaryExpression;
1110                 subscript->left = ref;
1111                 subscript->oper = &Operator::get_operator("[", Operator::BINARY);
1112                 subscript->right = pass.subscript;
1113
1114                 MemberAccess *memacc = new MemberAccess;
1115                 memacc->left = subscript;
1116                 memacc->member = "gl_Position";
1117
1118                 insert_assignment("gl_Position", memacc);
1119         }
1120
1121         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
1122         {
1123                 string out_name = change_prefix((*i)->name, out_prefix);
1124                 generate_interface(**i, "out", out_name);
1125
1126                 VariableReference *ref = new VariableReference;
1127                 ref->name = (*i)->name;
1128                 if(pass.subscript)
1129                 {
1130                         BinaryExpression *subscript = new BinaryExpression;
1131                         subscript->left = ref;
1132                         subscript->oper = &Operator::get_operator("[", Operator::BINARY);
1133                         subscript->right = pass.subscript;
1134                         insert_assignment(out_name, subscript);
1135                 }
1136                 else
1137                         insert_assignment(out_name, ref);
1138         }
1139
1140         nodes_to_remove.insert(&pass);
1141 }
1142
1143 } // namespace SL
1144 } // namespace GL
1145 } // namespace Msp