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_and_replace(RefPtr<Expression> &expr)
 242 {
 243         r_replacement_expr = 0;
 244         expr->visit(*this);
 245         if(r_replacement_expr)
 246                 expr = r_replacement_expr;
 247         r_replacement_expr = 0;
 248 }
 249
 250 void VariableResolver::visit(VariableReference &var)
 251 {
 252         VariableDeclaration *declaration = 0;
 253
 254         /* Look for variable declarations in the block hierarchy first.  Interface
 255         blocks are always defined in the top level so we can't accidentally skip
 256         one. */
 257         for(Block *block=current_block; (!declaration && block); block=block->parent)
 258         {
 259                 map<string, VariableDeclaration *>::iterator i = block->variables.find(var.name);
 260                 if(i!=block->variables.end())
 261                         declaration = i->second;
 262         }
 263
 264         if(!declaration)
 265         {
 266                 const map<string, InterfaceBlock *> &blocks = stage->interface_blocks;
 267                 map<string, InterfaceBlock *>::const_iterator i = blocks.find("_"+var.name);
 268                 if(i!=blocks.end())
 269                 {
 270                         /* The name refers to an interface block with an instance name rather
 271                         than a variable.  Prepare a new syntax tree node accordingly. */
 272                         InterfaceBlockReference *iface_ref = new InterfaceBlockReference;
 273                         iface_ref->source = var.source;
 274                         iface_ref->line = var.line;
 275                         iface_ref->name = var.name;
 276                         iface_ref->declaration = i->second;
 277                         r_replacement_expr = iface_ref;
 278                 }
 279                 else
 280                 {
 281                         // Look for the variable in anonymous interface blocks.
 282                         for(i=blocks.begin(); (!declaration && i!=blocks.end()); ++i)
 283                                 if(i->second->instance_name.empty())
 284                                 {
 285                                         map<string, VariableDeclaration *>::iterator j = i->second->members.variables.find(var.name);
 286                                         if(j!=i->second->members.variables.end())
 287                                                 declaration = j->second;
 288                                 }
 289                 }
 290         }
 291
 292         r_any_resolved |= (declaration!=var.declaration);
 293         var.declaration = declaration;
 294
 295         if(record_target)
 296         {
 297                 if(r_assignment_target)
 298                 {
 299                         /* More than one variable reference found in assignment target.
 300                         Unable to determine what the primary target is. */
 301                         record_target = false;
 302                         r_assignment_target = 0;
 303                 }
 304                 else
 305                         r_assignment_target = var.declaration;
 306         }
 307         else if(var.declaration && var.declaration==r_assignment_target)
 308                 r_self_referencing = true;
 309 }
 310
 311 void VariableResolver::visit(InterfaceBlockReference &iface)
 312 {
 313         map<string, InterfaceBlock *>::iterator i = stage->interface_blocks.find("_"+iface.name);
 314         InterfaceBlock *declaration = (i!=stage->interface_blocks.end() ? i->second : 0);
 315         r_any_resolved |= (declaration!=iface.declaration);
 316         iface.declaration = declaration;
 317 }
 318
 319 void VariableResolver::visit(MemberAccess &memacc)
 320 {
 321         visit_and_replace(memacc.left);
 322
 323         map<string, VariableDeclaration *> *members = 0;
 324         if(StructDeclaration *strct = dynamic_cast<StructDeclaration *>(memacc.left->type))
 325                 members = &strct->members.variables;
 326         else if(InterfaceBlockReference *iface_ref = dynamic_cast<InterfaceBlockReference *>(memacc.left.get()))
 327         {
 328                 if(iface_ref->declaration)
 329                         members = &iface_ref->declaration->members.variables;
 330         }
 331
 332         VariableDeclaration *declaration = 0;
 333         if(members)
 334         {
 335                 map<string, VariableDeclaration *>::iterator i = members->find(memacc.member);
 336                 if(i!=members->end())
 337                         declaration = i->second;
 338         }
 339
 340         r_any_resolved |= (declaration!=memacc.declaration);
 341         memacc.declaration = declaration;
 342 }
 343
 344 void VariableResolver::visit(UnaryExpression &unary)
 345 {
 346         visit_and_replace(unary.expression);
 347 }
 348
 349 void VariableResolver::visit(BinaryExpression &binary)
 350 {
 351         if(binary.oper->token[0]=='[')
 352         {
 353                 {
 354                         /* The subscript expression is not a part of the primary assignment
 355                         target. */
 356                         SetFlag set(record_target, false);
 357                         visit_and_replace(binary.right);
 358                 }
 359                 visit_and_replace(binary.left);
 360         }
 361         else
 362         {
 363                 visit_and_replace(binary.left);
 364                 visit_and_replace(binary.right);
 365         }
 366 }
 367
 368 void VariableResolver::visit(Assignment &assign)
 369 {
 370         {
 371                 SetFlag set(record_target);
 372                 r_assignment_target = 0;
 373                 visit_and_replace(assign.left);
 374                 r_any_resolved |= (r_assignment_target!=assign.target_declaration);
 375                 assign.target_declaration = r_assignment_target;
 376         }
 377
 378         r_self_referencing = false;
 379         visit_and_replace(assign.right);
 380         assign.self_referencing = (r_self_referencing || assign.oper->token[0]!='=');
 381 }
 382
 383 void VariableResolver::visit(FunctionCall &call)
 384 {
 385         for(NodeArray<Expression>::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
 386                 visit_and_replace(*i);
 387 }
 388
 389 void VariableResolver::visit(VariableDeclaration &var)
 390 {
 391         if(!block_interface.empty() && var.interface.empty())
 392                 var.interface = block_interface;
 393
 394         TraversingVisitor::visit(var);
 395         current_block->variables.insert(make_pair(var.name, &var));
 396 }
 397
 398 void VariableResolver::visit(InterfaceBlock &iface)
 399 {
 400         /* Block names can be reused in different interfaces.  Prefix the name with
 401         the first character of the interface to avoid conflicts. */
 402         stage->interface_blocks.insert(make_pair(iface.interface+iface.name, &iface));
 403         if(!iface.instance_name.empty())
 404                 stage->interface_blocks.insert(make_pair("_"+iface.instance_name, &iface));
 405
 406         SetForScope<string> set_iface(block_interface, iface.interface);
 407         TraversingVisitor::visit(iface);
 408 }
 409
 410
 411 ExpressionResolver::ExpressionResolver():
 412         stage(0),
 413         r_any_resolved(false)
 414 { }
 415
 416 bool ExpressionResolver::apply(Stage &s)
 417 {
 418         stage = &s;
 419         r_any_resolved = false;
 420         s.content.visit(*this);
 421         return r_any_resolved;
 422 }
 423
 424 bool ExpressionResolver::is_scalar(BasicTypeDeclaration &type)
 425 {
 426         return (type.kind==BasicTypeDeclaration::INT || type.kind==BasicTypeDeclaration::FLOAT);
 427 }
 428
 429 bool ExpressionResolver::is_vector_or_matrix(BasicTypeDeclaration &type)
 430 {
 431         return (type.kind==BasicTypeDeclaration::VECTOR || type.kind==BasicTypeDeclaration::MATRIX);
 432 }
 433
 434 BasicTypeDeclaration *ExpressionResolver::get_element_type(BasicTypeDeclaration &type)
 435 {
 436         if(is_vector_or_matrix(type) || type.kind==BasicTypeDeclaration::ARRAY)
 437         {
 438                 BasicTypeDeclaration *basic_base = dynamic_cast<BasicTypeDeclaration *>(type.base_type);
 439                 return (basic_base ? get_element_type(*basic_base) : 0);
 440         }
 441         else
 442                 return &type;
 443 }
 444
 445 bool ExpressionResolver::can_convert(BasicTypeDeclaration &from, BasicTypeDeclaration &to)
 446 {
 447         if(from.kind==BasicTypeDeclaration::INT && to.kind==BasicTypeDeclaration::FLOAT)
 448                 return from.size<=to.size;
 449         else if(from.kind!=to.kind)
 450                 return false;
 451         else if((from.kind==BasicTypeDeclaration::VECTOR || from.kind==BasicTypeDeclaration::MATRIX) && from.size==to.size)
 452         {
 453                 BasicTypeDeclaration *from_base = dynamic_cast<BasicTypeDeclaration *>(from.base_type);
 454                 BasicTypeDeclaration *to_base = dynamic_cast<BasicTypeDeclaration *>(to.base_type);
 455                 return (from_base && to_base && can_convert(*from_base, *to_base));
 456         }
 457         else
 458                 return false;
 459 }
 460
 461 ExpressionResolver::Compatibility ExpressionResolver::get_compatibility(BasicTypeDeclaration &left, BasicTypeDeclaration &right)
 462 {
 463         if(&left==&right)
 464                 return SAME_TYPE;
 465         else if(can_convert(left, right))
 466                 return LEFT_CONVERTIBLE;
 467         else if(can_convert(right, left))
 468                 return RIGHT_CONVERTIBLE;
 469         else
 470                 return NOT_COMPATIBLE;
 471 }
 472
 473 BasicTypeDeclaration *ExpressionResolver::find_type(BasicTypeDeclaration::Kind kind, unsigned size)
 474 {
 475         for(vector<BasicTypeDeclaration *>::const_iterator i=basic_types.begin(); i!=basic_types.end(); ++i)
 476                 if((*i)->kind==kind && (*i)->size==size)
 477                         return *i;
 478         return 0;
 479 }
 480
 481 BasicTypeDeclaration *ExpressionResolver::find_type(BasicTypeDeclaration &elem_type, BasicTypeDeclaration::Kind kind, unsigned size)
 482 {
 483         for(vector<BasicTypeDeclaration *>::const_iterator i=basic_types.begin(); i!=basic_types.end(); ++i)
 484                 if(get_element_type(**i)==&elem_type && (*i)->kind==kind && (*i)->size==size)
 485                         return *i;
 486         return 0;
 487 }
 488
 489 void ExpressionResolver::convert_to(RefPtr<Expression> &expr, BasicTypeDeclaration &type)
 490 {
 491         RefPtr<FunctionCall> call = new FunctionCall;
 492         call->name = type.name;
 493         call->constructor = true;
 494         call->arguments.push_back(0);
 495         call->arguments.back() = expr;
 496         call->type = &type;
 497         expr = call;
 498 }
 499
 500 bool ExpressionResolver::convert_to_element(RefPtr<Expression> &expr, BasicTypeDeclaration &elem_type)
 501 {
 502         if(BasicTypeDeclaration *expr_type = dynamic_cast<BasicTypeDeclaration *>(expr->type))
 503         {
 504                 BasicTypeDeclaration *to_type = &elem_type;
 505                 if(is_vector_or_matrix(*expr_type))
 506                         to_type = find_type(elem_type, expr_type->kind, expr_type->size);
 507                 if(to_type)
 508                 {
 509                         convert_to(expr, *to_type);
 510                         return true;
 511                 }
 512         }
 513
 514         return false;
 515 }
 516
 517 void ExpressionResolver::resolve(Expression &expr, TypeDeclaration *type, bool lvalue)
 518 {
 519         r_any_resolved |= (type!=expr.type || lvalue!=expr.lvalue);
 520         expr.type = type;
 521         expr.lvalue = lvalue;
 522 }
 523
 524 void ExpressionResolver::visit(Literal &literal)
 525 {
 526         if(literal.value.check_type<bool>())
 527                 resolve(literal, find_type(BasicTypeDeclaration::BOOL, 1), false);
 528         else if(literal.value.check_type<int>())
 529                 resolve(literal, find_type(BasicTypeDeclaration::INT, 32), false);
 530         else if(literal.value.check_type<float>())
 531                 resolve(literal, find_type(BasicTypeDeclaration::FLOAT, 32), false);
 532 }
 533
 534 void ExpressionResolver::visit(ParenthesizedExpression &parexpr)
 535 {
 536         TraversingVisitor::visit(parexpr);
 537         resolve(parexpr, parexpr.expression->type, parexpr.expression->lvalue);
 538 }
 539
 540 void ExpressionResolver::visit(VariableReference &var)
 541 {
 542         if(var.declaration)
 543                 resolve(var, var.declaration->type_declaration, true);
 544 }
 545
 546 void ExpressionResolver::visit(InterfaceBlockReference &iface)
 547 {
 548         resolve(iface, 0, true);
 549 }
 550
 551 void ExpressionResolver::visit(MemberAccess &memacc)
 552 {
 553         TraversingVisitor::visit(memacc);
 554
 555         if(memacc.declaration)
 556                 resolve(memacc, memacc.declaration->type_declaration, memacc.left->lvalue);
 557 }
 558
 559 void ExpressionResolver::visit(UnaryExpression &unary)
 560 {
 561         TraversingVisitor::visit(unary);
 562
 563         BasicTypeDeclaration *basic = dynamic_cast<BasicTypeDeclaration *>(unary.expression->type);
 564         if(!basic)
 565                 return;
 566
 567         char oper = unary.oper->token[0];
 568         if(oper=='!')
 569         {
 570                 if(basic->kind!=BasicTypeDeclaration::BOOL)
 571                         return;
 572         }
 573         else if(oper=='~')
 574         {
 575                 if(basic->kind!=BasicTypeDeclaration::INT)
 576                         return;
 577         }
 578         else if(oper=='+' || oper=='-')
 579         {
 580                 BasicTypeDeclaration *elem = get_element_type(*basic);
 581                 if(!elem || !is_scalar(*elem))
 582                         return;
 583         }
 584         resolve(unary, basic, unary.expression->lvalue);
 585 }
 586
 587 void ExpressionResolver::visit(BinaryExpression &binary, bool assign)
 588 {
 589         /* Binary operators are only defined for basic types (not for image or
 590         structure types). */
 591         BasicTypeDeclaration *basic_left = dynamic_cast<BasicTypeDeclaration *>(binary.left->type);
 592         BasicTypeDeclaration *basic_right = dynamic_cast<BasicTypeDeclaration *>(binary.right->type);
 593         if(!basic_left || !basic_right)
 594                 return;
 595
 596         char oper = binary.oper->token[0];
 597         if(oper=='[')
 598         {
 599                 /* Subscripting operates on vectors, matrices and arrays, and the right
 600                 operand must be an integer. */
 601                 if((!is_vector_or_matrix(*basic_left) && basic_left->kind!=BasicTypeDeclaration::ARRAY) || basic_right->kind!=BasicTypeDeclaration::INT)
 602                         return;
 603
 604                 resolve(binary, basic_left->base_type, binary.left->lvalue);
 605                 return;
 606         }
 607         else if(basic_left->kind==BasicTypeDeclaration::ARRAY || basic_right->kind==BasicTypeDeclaration::ARRAY)
 608                 // No other binary operator can be used with arrays.
 609                 return;
 610
 611         BasicTypeDeclaration *elem_left = get_element_type(*basic_left);
 612         BasicTypeDeclaration *elem_right = get_element_type(*basic_right);
 613         if(!elem_left || !elem_right)
 614                 return;
 615
 616         Compatibility compat = get_compatibility(*basic_left, *basic_right);
 617         Compatibility elem_compat = get_compatibility(*elem_left, *elem_right);
 618         if(elem_compat==NOT_COMPATIBLE)
 619                 return;
 620         if(assign && (compat==LEFT_CONVERTIBLE || elem_compat==LEFT_CONVERTIBLE))
 621                 return;
 622
 623         TypeDeclaration *type = 0;
 624         char oper2 = binary.oper->token[1];
 625         if((oper=='<' && oper2!='<') || (oper=='>' && oper2!='>'))
 626         {
 627                 /* Relational operators compare two scalar integer or floating-point
 628                 values. */
 629                 if(!is_scalar(*elem_left) || !is_scalar(*elem_right) || compat==NOT_COMPATIBLE)
 630                         return;
 631
 632                 type = find_type(BasicTypeDeclaration::BOOL, 1);
 633         }
 634         else if((oper=='=' || oper=='!') && oper2=='=')
 635         {
 636                 // Equality comparison can be done on any compatible types.
 637                 if(compat==NOT_COMPATIBLE)
 638                         return;
 639
 640                 type = find_type(BasicTypeDeclaration::BOOL, 1);
 641         }
 642         else if(oper2=='&' || oper2=='|' || oper2=='^')
 643         {
 644                 // Logical operators can only be applied to booleans.
 645                 if(basic_left->kind!=BasicTypeDeclaration::BOOL || basic_right->kind!=BasicTypeDeclaration::BOOL)
 646                         return;
 647
 648                 type = basic_left;
 649         }
 650         else if((oper=='&' || oper=='|' || oper=='^' || oper=='%') && !oper2)
 651         {
 652                 // Bitwise operators and modulo can only be applied to integers.
 653                 if(basic_left->kind!=BasicTypeDeclaration::INT || basic_right->kind!=BasicTypeDeclaration::INT)
 654                         return;
 655
 656                 type = (compat==LEFT_CONVERTIBLE ? basic_right : basic_left);
 657         }
 658         else if((oper=='<' || oper=='>') && oper2==oper)
 659         {
 660                 // Shifts apply to integer scalars and vectors, with some restrictions.
 661                 if(elem_left->kind!=BasicTypeDeclaration::INT || elem_right->kind!=BasicTypeDeclaration::INT)
 662                         return;
 663                 unsigned left_size = (basic_left->kind==BasicTypeDeclaration::INT ? 1 : basic_left->kind==BasicTypeDeclaration::VECTOR ? basic_left->size : 0);
 664                 unsigned right_size = (basic_right->kind==BasicTypeDeclaration::INT ? 1 : basic_right->kind==BasicTypeDeclaration::VECTOR ? basic_right->size : 0);
 665                 if(!left_size || (left_size==1 && right_size!=1) || (left_size>1 && right_size!=1 && right_size!=left_size))
 666                         return;
 667
 668                 type = basic_left;
 669                 // Don't perform conversion even if the operands are of different sizes.
 670                 compat = SAME_TYPE;
 671         }
 672         else if(oper=='+' || oper=='-' || oper=='*' || oper=='/')
 673         {
 674                 // Arithmetic operators require scalar elements.
 675                 if(!is_scalar(*elem_left) || !is_scalar(*elem_right))
 676                         return;
 677
 678                 if(oper=='*' && is_vector_or_matrix(*basic_left) && is_vector_or_matrix(*basic_right) &&
 679                         (basic_left->kind==BasicTypeDeclaration::MATRIX || basic_right->kind==BasicTypeDeclaration::MATRIX))
 680                 {
 681                         /* Multiplication has special rules when at least one operand is a
 682                         matrix and the other is a vector or a matrix. */
 683                         unsigned left_columns = basic_left->size&0xFFFF;
 684                         unsigned right_rows = basic_right->size;
 685                         if(basic_right->kind==BasicTypeDeclaration::MATRIX)
 686                                 right_rows >>= 16;
 687                         if(left_columns!=right_rows)
 688                                 return;
 689
 690                         BasicTypeDeclaration *elem_result = (elem_compat==LEFT_CONVERTIBLE ? elem_right : elem_left);
 691
 692                         if(basic_left->kind==BasicTypeDeclaration::VECTOR)
 693                                 type = find_type(*elem_result, BasicTypeDeclaration::VECTOR, basic_right->size&0xFFFF);
 694                         else if(basic_right->kind==BasicTypeDeclaration::VECTOR)
 695                                 type = find_type(*elem_result, BasicTypeDeclaration::VECTOR, basic_left->size>>16);
 696                         else
 697                                 type = find_type(*elem_result, BasicTypeDeclaration::MATRIX, (basic_left->size&0xFFFF0000)|(basic_right->size&0xFFFF));
 698                 }
 699                 else if(compat==NOT_COMPATIBLE)
 700                 {
 701                         // Arithmetic between scalars and matrices or vectors is supported.
 702                         if(is_scalar(*basic_left) && is_vector_or_matrix(*basic_right))
 703                                 type = (elem_compat==RIGHT_CONVERTIBLE ? find_type(*elem_left, basic_right->kind, basic_right->size) : basic_right);
 704                         else if(is_vector_or_matrix(*basic_left) && is_scalar(*basic_right))
 705                                 type = (elem_compat==LEFT_CONVERTIBLE ? find_type(*elem_right, basic_left->kind, basic_left->size) : basic_left);
 706                         else
 707                                 return;
 708                 }
 709                 else if(compat==LEFT_CONVERTIBLE)
 710                         type = basic_right;
 711                 else
 712                         type = basic_left;
 713         }
 714         else
 715                 return;
 716
 717         if(assign && type!=basic_left)
 718                 return;
 719
 720         bool converted = true;
 721         if(compat==LEFT_CONVERTIBLE)
 722                 convert_to(binary.left, *basic_right);
 723         else if(compat==RIGHT_CONVERTIBLE)
 724                 convert_to(binary.right, *basic_left);
 725         else if(elem_compat==LEFT_CONVERTIBLE)
 726                 converted = convert_to_element(binary.left, *elem_right);
 727         else if(elem_compat==RIGHT_CONVERTIBLE)
 728                 converted = convert_to_element(binary.right, *elem_left);
 729
 730         if(!converted)
 731                 type = 0;
 732
 733         resolve(binary, type, assign);
 734 }
 735
 736 void ExpressionResolver::visit(BinaryExpression &binary)
 737 {
 738         TraversingVisitor::visit(binary);
 739         visit(binary, false);
 740 }
 741
 742 void ExpressionResolver::visit(Assignment &assign)
 743 {
 744         TraversingVisitor::visit(assign);
 745
 746         if(assign.oper->token[0]!='=')
 747                 return visit(assign, true);
 748         else if(assign.left->type!=assign.right->type)
 749         {
 750                 BasicTypeDeclaration *basic_left = dynamic_cast<BasicTypeDeclaration *>(assign.left->type);
 751                 BasicTypeDeclaration *basic_right = dynamic_cast<BasicTypeDeclaration *>(assign.right->type);
 752                 if(!basic_left || !basic_right)
 753                         return;
 754
 755                 Compatibility compat = get_compatibility(*basic_left, *basic_right);
 756                 if(compat==RIGHT_CONVERTIBLE)
 757                         convert_to(assign.right, *basic_left);
 758                 else if(compat!=SAME_TYPE)
 759                         return;
 760         }
 761
 762         resolve(assign, assign.left->type, true);
 763 }
 764
 765 void ExpressionResolver::visit(FunctionCall &call)
 766 {
 767         TraversingVisitor::visit(call);
 768
 769         TypeDeclaration *type = 0;
 770         if(call.declaration)
 771                 type = call.declaration->return_type_declaration;
 772         else if(call.constructor)
 773         {
 774                 map<string, TypeDeclaration *>::const_iterator i=stage->types.find(call.name);
 775                 type = (i!=stage->types.end() ? i->second : 0);
 776         }
 777         resolve(call, type, false);
 778 }
 779
 780 void ExpressionResolver::visit(BasicTypeDeclaration &type)
 781 {
 782         basic_types.push_back(&type);
 783 }
 784
 785 void ExpressionResolver::visit(VariableDeclaration &var)
 786 {
 787         TraversingVisitor::visit(var);
 788         if(!var.init_expression)
 789                 return;
 790
 791         BasicTypeDeclaration *var_basic = dynamic_cast<BasicTypeDeclaration *>(var.type_declaration);
 792         BasicTypeDeclaration *init_basic = dynamic_cast<BasicTypeDeclaration *>(var.init_expression->type);
 793         if(!var_basic || !init_basic)
 794                 return;
 795
 796         Compatibility compat = get_compatibility(*var_basic, *init_basic);
 797         if(compat==RIGHT_CONVERTIBLE)
 798                 convert_to(var.init_expression, *var_basic);
 799 }
 800
 801
 802 void FunctionResolver::apply(Stage &s)
 803 {
 804         stage = &s;
 805         s.functions.clear();
 806         s.content.visit(*this);
 807 }
 808
 809 void FunctionResolver::visit(FunctionCall &call)
 810 {
 811         map<string, FunctionDeclaration *>::iterator i = stage->functions.find(call.name);
 812         if(i!=stage->functions.end())
 813                 call.declaration = i->second;
 814
 815         TraversingVisitor::visit(call);
 816 }
 817
 818 void FunctionResolver::visit(FunctionDeclaration &func)
 819 {
 820         FunctionDeclaration *&stage_decl = stage->functions[func.name];
 821         vector<FunctionDeclaration *> &decls = declarations[func.name];
 822         if(func.definition==&func)
 823         {
 824                 stage_decl = &func;
 825
 826                 // Set all previous declarations to use this definition.
 827                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 828                 {
 829                         (*i)->definition = func.definition;
 830                         (*i)->body.body.clear();
 831                 }
 832         }
 833         else
 834         {
 835                 func.definition = 0;
 836                 if(!stage_decl)
 837                         stage_decl = &func;
 838                 else
 839                         func.definition = stage_decl->definition;
 840         }
 841         decls.push_back(&func);
 842
 843         TraversingVisitor::visit(func);
 844 }
 845
 846
 847 InterfaceGenerator::InterfaceGenerator():
 848         stage(0),
 849         function_scope(false),
 850         iface_block(0),
 851         copy_block(false),
 852         iface_target_block(0)
 853 { }
 854
 855 string InterfaceGenerator::get_out_prefix(Stage::Type type)
 856 {
 857         if(type==Stage::VERTEX)
 858                 return "_vs_out_";
 859         else if(type==Stage::GEOMETRY)
 860                 return "_gs_out_";
 861         else
 862                 return string();
 863 }
 864
 865 void InterfaceGenerator::apply(Stage &s)
 866 {
 867         stage = &s;
 868         iface_target_block = &stage->content;
 869         if(stage->previous)
 870                 in_prefix = get_out_prefix(stage->previous->type);
 871         out_prefix = get_out_prefix(stage->type);
 872         s.content.visit(*this);
 873         NodeRemover().apply(s, nodes_to_remove);
 874 }
 875
 876 void InterfaceGenerator::visit(Block &block)
 877 {
 878         SetForScope<Block *> set_block(current_block, &block);
 879         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 880         {
 881                 assignment_insert_point = i;
 882                 if(&block==&stage->content)
 883                         iface_insert_point = i;
 884
 885                 (*i)->visit(*this);
 886         }
 887 }
 888
 889 string InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
 890 {
 891         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
 892         return prefix+name.substr(offset);
 893 }
 894
 895 VariableDeclaration *InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
 896 {
 897         if(stage->content.variables.count(name))
 898                 return 0;
 899
 900         VariableDeclaration* iface_var = new VariableDeclaration;
 901         iface_var->sampling = var.sampling;
 902         iface_var->interface = iface;
 903         iface_var->type = var.type;
 904         iface_var->name = name;
 905         /* Geometry shader inputs are always arrays.  But if we're bringing in an
 906         entire block, the array is on the block and not individual variables. */
 907         if(stage->type==Stage::GEOMETRY && !copy_block)
 908                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
 909         else
 910                 iface_var->array = var.array;
 911         if(iface_var->array)
 912                 iface_var->array_size = var.array_size;
 913         if(iface=="in")
 914         {
 915                 iface_var->layout = var.layout;
 916                 iface_var->linked_declaration = &var;
 917                 var.linked_declaration = iface_var;
 918         }
 919
 920         iface_target_block->body.insert(iface_insert_point, iface_var);
 921         iface_target_block->variables.insert(make_pair(name, iface_var));
 922
 923         return iface_var;
 924 }
 925
 926 InterfaceBlock *InterfaceGenerator::generate_interface(InterfaceBlock &out_block)
 927 {
 928         if(stage->interface_blocks.count("in"+out_block.name))
 929                 return 0;
 930
 931         InterfaceBlock *in_block = new InterfaceBlock;
 932         in_block->interface = "in";
 933         in_block->name = out_block.name;
 934         in_block->instance_name = out_block.instance_name;
 935         if(stage->type==Stage::GEOMETRY)
 936                 in_block->array = true;
 937         else
 938                 in_block->array = out_block.array;
 939         in_block->linked_block = &out_block;
 940         out_block.linked_block = in_block;
 941
 942         {
 943                 SetFlag set_copy(copy_block, true);
 944                 SetForScope<Block *> set_target(iface_target_block, &in_block->members);
 945                 SetForScope<NodeList<Statement>::iterator> set_ins_pt(iface_insert_point, in_block->members.body.end());
 946                 out_block.members.visit(*this);
 947         }
 948
 949         iface_target_block->body.insert(iface_insert_point, in_block);
 950         stage->interface_blocks.insert(make_pair("in"+in_block->name, in_block));
 951         if(!in_block->instance_name.empty())
 952                 stage->interface_blocks.insert(make_pair("_"+in_block->instance_name, in_block));
 953
 954         SetFlag set_scope(function_scope, false);
 955         SetForScope<Block *> set_block(current_block, &stage->content);
 956         in_block->visit(*this);
 957
 958         return in_block;
 959 }
 960
 961 ExpressionStatement &InterfaceGenerator::insert_assignment(const string &left, Expression *right)
 962 {
 963         Assignment *assign = new Assignment;
 964         VariableReference *ref = new VariableReference;
 965         ref->name = left;
 966         assign->left = ref;
 967         assign->oper = &Operator::get_operator("=", Operator::BINARY);
 968         assign->right = right;
 969
 970         ExpressionStatement *stmt = new ExpressionStatement;
 971         stmt->expression = assign;
 972         current_block->body.insert(assignment_insert_point, stmt);
 973         stmt->visit(*this);
 974
 975         return *stmt;
 976 }
 977
 978 void InterfaceGenerator::visit(VariableReference &var)
 979 {
 980         if(var.declaration || !stage->previous)
 981                 return;
 982         /* Don't pull a variable from previous stage if we just generated an output
 983         interface in this stage */
 984         if(stage->content.variables.count(var.name))
 985                 return;
 986
 987         const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
 988         map<string, VariableDeclaration *>::const_iterator i = prev_vars.find(var.name);
 989         if(i==prev_vars.end() || i->second->interface!="out")
 990                 i = prev_vars.find(in_prefix+var.name);
 991         if(i!=prev_vars.end() && i->second->interface=="out")
 992         {
 993                 generate_interface(*i->second, "in", i->second->name);
 994                 var.name = i->second->name;
 995                 return;
 996         }
 997
 998         const map<string, InterfaceBlock *> &prev_blocks = stage->previous->interface_blocks;
 999         map<string, InterfaceBlock *>::const_iterator j = prev_blocks.find("_"+var.name);
1000         if(j!=prev_blocks.end() && j->second->interface=="out")
1001         {
1002                 generate_interface(*j->second);
1003                 /* Let VariableResolver convert the variable reference into an interface
1004                 block reference. */
1005                 return;
1006         }
1007
1008         for(j=prev_blocks.begin(); j!=prev_blocks.end(); ++j)
1009                 if(j->second->instance_name.empty())
1010                 {
1011                         i = j->second->members.variables.find(var.name);
1012                         if(i!=j->second->members.variables.end())
1013                         {
1014                                 generate_interface(*j->second);
1015                                 return;
1016                         }
1017                 }
1018 }
1019
1020 void InterfaceGenerator::visit(VariableDeclaration &var)
1021 {
1022         if(copy_block)
1023         {
1024                 generate_interface(var, "in", var.name);
1025                 return;
1026         }
1027
1028         if(iface_block)
1029         {
1030                 if(iface_block->linked_block)
1031                 {
1032                         // Link all variables to their counterparts in the linked block.
1033                         const map<string, VariableDeclaration *> &linked_vars = iface_block->linked_block->members.variables;
1034                         map<string, VariableDeclaration *>::const_iterator i = linked_vars.find(var.name);
1035                         if(i!=linked_vars.end())
1036                         {
1037                                 var.linked_declaration = i->second;
1038                                 var.linked_declaration->linked_declaration = &var;
1039                         }
1040                 }
1041                 return;
1042         }
1043
1044         if(var.interface=="out")
1045         {
1046                 /* For output variables in function scope, generate a global interface
1047                 and replace the local declaration with an assignment. */
1048                 VariableDeclaration *out_var = 0;
1049                 if(function_scope && (out_var=generate_interface(var, "out", var.name)))
1050                 {
1051                         out_var->source = var.source;
1052                         out_var->line = var.line;
1053                         nodes_to_remove.insert(&var);
1054                         if(var.init_expression)
1055                         {
1056                                 ExpressionStatement &stmt = insert_assignment(var.name, var.init_expression->clone());
1057                                 stmt.source = var.source;
1058                                 stmt.line = var.line;
1059                                 return;
1060                         }
1061                 }
1062         }
1063         else if(var.interface=="in")
1064         {
1065                 /* Try to link input variables in global scope with output variables from
1066                 previous stage. */
1067                 if(current_block==&stage->content && !var.linked_declaration && stage->previous)
1068                 {
1069                         const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
1070                         map<string, VariableDeclaration *>::const_iterator i = prev_vars.find(var.name);
1071                         if(i!=prev_vars.end() && i->second->interface=="out")
1072                         {
1073                                 var.linked_declaration = i->second;
1074                                 i->second->linked_declaration = &var;
1075                         }
1076                 }
1077         }
1078
1079         TraversingVisitor::visit(var);
1080 }
1081
1082 void InterfaceGenerator::visit(InterfaceBlock &iface)
1083 {
1084         if(iface.interface=="in")
1085         {
1086                 /* Try to link input blocks with output blocks sharing the same block
1087                 name from previous stage. */
1088                 if(!iface.linked_block && stage->previous)
1089                 {
1090                         const map<string, InterfaceBlock *> &prev_blocks = stage->previous->interface_blocks;
1091                         map<string, InterfaceBlock *>::const_iterator i = prev_blocks.find("out"+iface.name);
1092                         if(i!=prev_blocks.end())
1093                         {
1094                                 iface.linked_block = i->second;
1095                                 i->second->linked_block = &iface;
1096                         }
1097                 }
1098         }
1099
1100         SetForScope<InterfaceBlock *> set_iface(iface_block, &iface);
1101         TraversingVisitor::visit(iface);
1102 }
1103
1104 void InterfaceGenerator::visit(FunctionDeclaration &func)
1105 {
1106         SetFlag set_scope(function_scope, true);
1107         // Skip parameters because they're not useful here
1108         func.body.visit(*this);
1109 }
1110
1111 void InterfaceGenerator::visit(Passthrough &pass)
1112 {
1113         vector<VariableDeclaration *> pass_vars;
1114
1115         // Pass through all input variables of this stage.
1116         for(map<string, VariableDeclaration *>::const_iterator i=stage->content.variables.begin(); i!=stage->content.variables.end(); ++i)
1117                 if(i->second->interface=="in")
1118                         pass_vars.push_back(i->second);
1119
1120         if(stage->previous)
1121         {
1122                 const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
1123                 for(map<string, VariableDeclaration *>::const_iterator i=prev_vars.begin(); i!=prev_vars.end(); ++i)
1124                 {
1125                         if(i->second->interface!="out")
1126                                 continue;
1127
1128                         /* Pass through output variables from the previous stage, but only
1129                         those which are not already linked to an input here. */
1130                         if(!i->second->linked_declaration && generate_interface(*i->second, "in", i->second->name))
1131                                 pass_vars.push_back(i->second);
1132                 }
1133         }
1134
1135         if(stage->type==Stage::GEOMETRY)
1136         {
1137                 /* Special case for geometry shader: copy gl_Position from input to
1138                 output. */
1139                 InterfaceBlockReference *ref = new InterfaceBlockReference;
1140                 ref->name = "gl_in";
1141
1142                 BinaryExpression *subscript = new BinaryExpression;
1143                 subscript->left = ref;
1144                 subscript->oper = &Operator::get_operator("[", Operator::BINARY);
1145                 subscript->right = pass.subscript;
1146
1147                 MemberAccess *memacc = new MemberAccess;
1148                 memacc->left = subscript;
1149                 memacc->member = "gl_Position";
1150
1151                 insert_assignment("gl_Position", memacc);
1152         }
1153
1154         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
1155         {
1156                 string out_name = change_prefix((*i)->name, out_prefix);
1157                 generate_interface(**i, "out", out_name);
1158
1159                 VariableReference *ref = new VariableReference;
1160                 ref->name = (*i)->name;
1161                 if(pass.subscript)
1162                 {
1163                         BinaryExpression *subscript = new BinaryExpression;
1164                         subscript->left = ref;
1165                         subscript->oper = &Operator::get_operator("[", Operator::BINARY);
1166                         subscript->right = pass.subscript;
1167                         insert_assignment(out_name, subscript);
1168                 }
1169                 else
1170                         insert_assignment(out_name, ref);
1171         }
1172
1173         nodes_to_remove.insert(&pass);
1174 }
1175
1176 } // namespace SL
1177 } // namespace GL
1178 } // namespace Msp