source/glsl/generate.cpp

   1 #include <algorithm>
   2 #include <msp/core/hash.h>
   3 #include <msp/core/raii.h>
   4 #include <msp/strings/lexicalcast.h>
   5 #include <msp/strings/utils.h>
   6 #include "builtin.h"
   7 #include "generate.h"
   8
   9 using namespace std;
  10
  11 namespace Msp {
  12 namespace GL {
  13 namespace SL {
  14
  15 ConstantSpecializer::ConstantSpecializer():
  16         values(0)
  17 { }
  18
  19 void ConstantSpecializer::apply(Stage &stage, const map<string, int> *v)
  20 {
  21         values = v;
  22         stage.content.visit(*this);
  23 }
  24
  25 void ConstantSpecializer::visit(VariableDeclaration &var)
  26 {
  27         bool specializable = false;
  28         if(var.layout)
  29         {
  30                 vector<Layout::Qualifier> &qualifiers = var.layout->qualifiers;
  31                 for(vector<Layout::Qualifier>::iterator i=qualifiers.begin(); i!=qualifiers.end(); ++i)
  32                         if(i->name=="constant_id")
  33                         {
  34                                 specializable = true;
  35                                 if(values)
  36                                         qualifiers.erase(i);
  37                                 else if(i->value==-1)
  38                                         i->value = hash32(var.name)&0x7FFFFFFF;
  39                                 break;
  40                         }
  41
  42                 if(qualifiers.empty())
  43                         var.layout = 0;
  44         }
  45
  46         if(specializable && values)
  47         {
  48                 map<string, int>::const_iterator i = values->find(var.name);
  49                 if(i!=values->end())
  50                 {
  51                         RefPtr<Literal> literal = new Literal;
  52                         if(var.type=="bool")
  53                         {
  54                                 literal->token = (i->second ? "true" : "false");
  55                                 literal->value = static_cast<bool>(i->second);
  56                         }
  57                         else if(var.type=="int")
  58                         {
  59                                 literal->token = lexical_cast<string>(i->second);
  60                                 literal->value = i->second;
  61                         }
  62                         var.init_expression = literal;
  63                 }
  64         }
  65 }
  66
  67
  68 void BlockHierarchyResolver::enter(Block &block)
  69 {
  70         r_any_resolved |= (current_block!=block.parent);
  71         block.parent = current_block;
  72 }
  73
  74
  75 TypeResolver::TypeResolver():
  76         stage(0),
  77         iface_block(0),
  78         r_any_resolved(false)
  79 { }
  80
  81 bool TypeResolver::apply(Stage &s)
  82 {
  83         stage = &s;
  84         s.types.clear();
  85         r_any_resolved = false;
  86         s.content.visit(*this);
  87         return r_any_resolved;
  88 }
  89
  90 TypeDeclaration *TypeResolver::get_or_create_array_type(TypeDeclaration &type)
  91 {
  92         map<TypeDeclaration *, TypeDeclaration *>::iterator i = array_types.find(&type);
  93         if(i!=array_types.end())
  94                 return i->second;
  95
  96         BasicTypeDeclaration *array = new BasicTypeDeclaration;
  97         array->source = BUILTIN_SOURCE;
  98         array->name = type.name+"[]";
  99         array->kind = BasicTypeDeclaration::ARRAY;
 100         array->base = type.name;
 101         array->base_type = &type;
 102         stage->content.body.insert(type_insert_point, array);
 103         array_types[&type] = array;
 104         return array;
 105 }
 106
 107 void TypeResolver::resolve_type(TypeDeclaration *&type, const string &name, bool array)
 108 {
 109         TypeDeclaration *resolved = 0;
 110         map<string, TypeDeclaration *>::iterator i = stage->types.find(name);
 111         if(i!=stage->types.end())
 112         {
 113                 map<TypeDeclaration *, TypeDeclaration *>::iterator j = alias_map.find(i->second);
 114                 resolved = (j!=alias_map.end() ? j->second : i->second);
 115         }
 116
 117         if(resolved && array)
 118                 resolved = get_or_create_array_type(*resolved);
 119
 120         r_any_resolved |= (resolved!=type);
 121         type=resolved;
 122 }
 123
 124 void TypeResolver::visit(Block &block)
 125 {
 126         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 127         {
 128                 if(!block.parent)
 129                         type_insert_point = i;
 130                 (*i)->visit(*this);
 131         }
 132 }
 133
 134 void TypeResolver::visit(BasicTypeDeclaration &type)
 135 {
 136         resolve_type(type.base_type, type.base, false);
 137
 138         if(type.kind==BasicTypeDeclaration::VECTOR && type.base_type)
 139                 if(BasicTypeDeclaration *basic_base = dynamic_cast<BasicTypeDeclaration *>(type.base_type))
 140                         if(basic_base->kind==BasicTypeDeclaration::VECTOR)
 141                         {
 142                                 type.kind = BasicTypeDeclaration::MATRIX;
 143                                 /* A matrix's base type is its column vector type.  This will put
 144                                 the column vector's size, i.e. the matrix's row count, in the high
 145                                 half of the size. */
 146                                 type.size |= basic_base->size<<16;
 147                         }
 148
 149         if(type.kind==BasicTypeDeclaration::ALIAS && type.base_type)
 150                 alias_map[&type] = type.base_type;
 151         else if(type.kind==BasicTypeDeclaration::ARRAY && type.base_type)
 152                 array_types[type.base_type] = &type;
 153
 154         stage->types.insert(make_pair(type.name, &type));
 155 }
 156
 157 void TypeResolver::visit(ImageTypeDeclaration &type)
 158 {
 159         resolve_type(type.base_type, type.base, false);
 160         stage->types.insert(make_pair(type.name, &type));
 161 }
 162
 163 void TypeResolver::visit(StructDeclaration &strct)
 164 {
 165         stage->types.insert(make_pair(strct.name, &strct));
 166         TraversingVisitor::visit(strct);
 167 }
 168
 169 void TypeResolver::visit(VariableDeclaration &var)
 170 {
 171         resolve_type(var.type_declaration, var.type, var.array);
 172         if(iface_block && var.interface==iface_block->interface)
 173                 var.interface.clear();
 174 }
 175
 176 void TypeResolver::visit(InterfaceBlock &iface)
 177 {
 178         if(iface.members)
 179         {
 180                 SetForScope<InterfaceBlock *> set_iface(iface_block, &iface);
 181                 iface.members->visit(*this);
 182
 183                 StructDeclaration *strct = new StructDeclaration;
 184                 strct->source = INTERNAL_SOURCE;
 185                 strct->name = format("_%s_%s", iface.interface, iface.name);
 186                 strct->members.body.splice(strct->members.body.begin(), iface.members->body);
 187                 stage->content.body.insert(type_insert_point, strct);
 188                 stage->types.insert(make_pair(strct->name, strct));
 189
 190                 iface.members = 0;
 191                 strct->interface_block = &iface;
 192                 iface.struct_declaration = strct;
 193         }
 194
 195         TypeDeclaration *type = iface.struct_declaration;
 196         if(type && iface.array)
 197                 type = get_or_create_array_type(*type);
 198         r_any_resolved = (type!=iface.type_declaration);
 199         iface.type_declaration = type;
 200 }
 201
 202 void TypeResolver::visit(FunctionDeclaration &func)
 203 {
 204         resolve_type(func.return_type_declaration, func.return_type, false);
 205         TraversingVisitor::visit(func);
 206 }
 207
 208
 209 VariableResolver::VariableResolver():
 210         stage(0),
 211         r_any_resolved(false),
 212         record_target(false),
 213         r_self_referencing(false)
 214 { }
 215
 216 bool VariableResolver::apply(Stage &s)
 217 {
 218         stage = &s;
 219         s.interface_blocks.clear();
 220         r_any_resolved = false;
 221         s.content.visit(*this);
 222         for(vector<VariableDeclaration *>::const_iterator i=redeclared_builtins.begin(); i!=redeclared_builtins.end(); ++i)
 223                 (*i)->source = GENERATED_SOURCE;
 224         NodeRemover().apply(s, nodes_to_remove);
 225         return r_any_resolved;
 226 }
 227
 228 void VariableResolver::enter(Block &block)
 229 {
 230         block.variables.clear();
 231 }
 232
 233 void VariableResolver::visit(RefPtr<Expression> &expr)
 234 {
 235         r_replacement_expr = 0;
 236         expr->visit(*this);
 237         if(r_replacement_expr)
 238         {
 239                 expr = r_replacement_expr;
 240                 /* Don't record assignment target when doing a replacement, because chain
 241                 information won't be correct. */
 242                 r_assignment_target.declaration = 0;
 243                 r_any_resolved = true;
 244         }
 245         r_replacement_expr = 0;
 246 }
 247
 248 void VariableResolver::check_assignment_target(Statement *declaration)
 249 {
 250         if(record_target)
 251         {
 252                 if(r_assignment_target.declaration)
 253                 {
 254                         /* More than one reference found in assignment target.  Unable to
 255                         determine what the primary target is. */
 256                         record_target = false;
 257                         r_assignment_target.declaration = 0;
 258                 }
 259                 else
 260                         r_assignment_target.declaration = declaration;
 261         }
 262         // TODO This check is overly broad and may prevent some optimizations.
 263         else if(declaration && declaration==r_assignment_target.declaration)
 264                 r_self_referencing = true;
 265 }
 266
 267 void VariableResolver::visit(VariableReference &var)
 268 {
 269         VariableDeclaration *declaration = 0;
 270
 271         /* Look for variable declarations in the block hierarchy first.  Interface
 272         blocks are always defined in the top level so we can't accidentally skip
 273         one. */
 274         for(Block *block=current_block; (!declaration && block); block=block->parent)
 275         {
 276                 map<string, VariableDeclaration *>::iterator i = block->variables.find(var.name);
 277                 if(i!=block->variables.end())
 278                         declaration = i->second;
 279         }
 280
 281         if(!declaration)
 282         {
 283                 const map<string, InterfaceBlock *> &blocks = stage->interface_blocks;
 284                 map<string, InterfaceBlock *>::const_iterator i = blocks.find("_"+var.name);
 285                 if(i!=blocks.end())
 286                 {
 287                         /* The name refers to an interface block with an instance name rather
 288                         than a variable.  Prepare a new syntax tree node accordingly. */
 289                         InterfaceBlockReference *iface_ref = new InterfaceBlockReference;
 290                         iface_ref->source = var.source;
 291                         iface_ref->line = var.line;
 292                         iface_ref->name = var.name;
 293                         iface_ref->declaration = i->second;
 294                         r_replacement_expr = iface_ref;
 295                 }
 296                 else
 297                 {
 298                         // Look for the variable in anonymous interface blocks.
 299                         for(i=blocks.begin(); (!declaration && i!=blocks.end()); ++i)
 300                                 if(i->second->instance_name.empty() && i->second->struct_declaration)
 301                                 {
 302                                         const map<string, VariableDeclaration *> &iface_vars = i->second->struct_declaration->members.variables;
 303                                         map<string, VariableDeclaration *>::const_iterator j = iface_vars.find(var.name);
 304                                         if(j!=iface_vars.end())
 305                                                 declaration = j->second;
 306                                 }
 307                 }
 308         }
 309
 310         r_any_resolved |= (declaration!=var.declaration);
 311         var.declaration = declaration;
 312
 313         check_assignment_target(var.declaration);
 314 }
 315
 316 void VariableResolver::visit(InterfaceBlockReference &iface)
 317 {
 318         map<string, InterfaceBlock *>::iterator i = stage->interface_blocks.find("_"+iface.name);
 319         InterfaceBlock *declaration = (i!=stage->interface_blocks.end() ? i->second : 0);
 320         r_any_resolved |= (declaration!=iface.declaration);
 321         iface.declaration = declaration;
 322
 323         check_assignment_target(iface.declaration);
 324 }
 325
 326 void VariableResolver::add_to_chain(Assignment::Target::ChainType type, unsigned index)
 327 {
 328         if(r_assignment_target.chain_len<7)
 329                 r_assignment_target.chain[r_assignment_target.chain_len] = type | min<unsigned>(index, 0x3F);
 330         ++r_assignment_target.chain_len;
 331 }
 332
 333 void VariableResolver::visit(MemberAccess &memacc)
 334 {
 335         TraversingVisitor::visit(memacc);
 336
 337         VariableDeclaration *declaration = 0;
 338         if(StructDeclaration *strct = dynamic_cast<StructDeclaration *>(memacc.left->type))
 339         {
 340                 map<string, VariableDeclaration *>::iterator i = strct->members.variables.find(memacc.member);
 341                 if(i!=strct->members.variables.end())
 342                 {
 343                         declaration = i->second;
 344
 345                         if(record_target)
 346                         {
 347                                 unsigned index = 0;
 348                                 for(NodeList<Statement>::const_iterator j=strct->members.body.begin(); (j!=strct->members.body.end() && j->get()!=i->second); ++j)
 349                                         ++index;
 350
 351                                 add_to_chain(Assignment::Target::MEMBER, index);
 352                         }
 353                 }
 354         }
 355         else if(BasicTypeDeclaration *basic = dynamic_cast<BasicTypeDeclaration *>(memacc.left->type))
 356         {
 357                 bool scalar_swizzle = ((basic->kind==BasicTypeDeclaration::INT || basic->kind==BasicTypeDeclaration::FLOAT) && memacc.member.size()==1);
 358                 bool vector_swizzle = (basic->kind==BasicTypeDeclaration::VECTOR && memacc.member.size()<=4);
 359                 if(scalar_swizzle || vector_swizzle)
 360                 {
 361                         static const char component_names[] = { 'x', 'r', 's', 'y', 'g', 't', 'z', 'b', 'p', 'w', 'a', 'q' };
 362
 363                         bool ok = true;
 364                         UInt8 components[4] = { };
 365                         for(unsigned i=0; (ok && i<memacc.member.size()); ++i)
 366                                 ok = ((components[i] = (find(component_names, component_names+12, memacc.member[i])-component_names)/3) < 4);
 367
 368                         if(ok)
 369                         {
 370                                 Swizzle *swizzle = new Swizzle;
 371                                 swizzle->source = memacc.source;
 372                                 swizzle->line = memacc.line;
 373                                 swizzle->oper = memacc.oper;
 374                                 swizzle->left = memacc.left;
 375                                 swizzle->component_group = memacc.member;
 376                                 swizzle->count = memacc.member.size();
 377                                 copy(components, components+memacc.member.size(), swizzle->components);
 378                                 r_replacement_expr = swizzle;
 379                         }
 380                 }
 381         }
 382
 383         r_any_resolved |= (declaration!=memacc.declaration);
 384         memacc.declaration = declaration;
 385 }
 386
 387 void VariableResolver::visit(Swizzle &swizzle)
 388 {
 389         TraversingVisitor::visit(swizzle);
 390
 391         if(record_target)
 392         {
 393                 unsigned mask = 0;
 394                 for(unsigned i=0; i<swizzle.count; ++i)
 395                         mask |= 1<<swizzle.components[i];
 396                 add_to_chain(Assignment::Target::SWIZZLE, mask);
 397         }
 398 }
 399
 400 void VariableResolver::visit(BinaryExpression &binary)
 401 {
 402         if(binary.oper->token[0]=='[')
 403         {
 404                 {
 405                         /* The subscript expression is not a part of the primary assignment
 406                         target. */
 407                         SetFlag set(record_target, false);
 408                         visit(binary.right);
 409                 }
 410                 visit(binary.left);
 411
 412                 if(record_target)
 413                 {
 414                         unsigned index = 0x3F;
 415                         if(Literal *literal_subscript = dynamic_cast<Literal *>(binary.right.get()))
 416                                 if(literal_subscript->value.check_type<int>())
 417                                         index = literal_subscript->value.value<int>();
 418                         add_to_chain(Assignment::Target::ARRAY, index);
 419                 }
 420         }
 421         else
 422                 TraversingVisitor::visit(binary);
 423 }
 424
 425 void VariableResolver::visit(Assignment &assign)
 426 {
 427         {
 428                 SetFlag set(record_target);
 429                 r_assignment_target = Assignment::Target();
 430                 visit(assign.left);
 431                 r_any_resolved |= (r_assignment_target<assign.target || assign.target<r_assignment_target);
 432                 assign.target = r_assignment_target;
 433         }
 434
 435         r_self_referencing = false;
 436         visit(assign.right);
 437         assign.self_referencing = (r_self_referencing || assign.oper->token[0]!='=');
 438 }
 439
 440 void VariableResolver::merge_layouts(Layout &to_layout, const Layout &from_layout)
 441 {
 442         for(vector<Layout::Qualifier>::const_iterator i=from_layout.qualifiers.begin(); i!=from_layout.qualifiers.end(); ++i)
 443         {
 444                 bool found = false;
 445                 for(vector<Layout::Qualifier>::iterator j=to_layout.qualifiers.begin(); (!found && j!=to_layout.qualifiers.end()); ++j)
 446                         if(j->name==i->name)
 447                         {
 448                                 j->has_value = i->value;
 449                                 j->value = i->value;
 450                                 found = true;
 451                         }
 452
 453                 if(!found)
 454                         to_layout.qualifiers.push_back(*i);
 455         }
 456 }
 457
 458 void VariableResolver::visit(VariableDeclaration &var)
 459 {
 460         TraversingVisitor::visit(var);
 461         VariableDeclaration *&ptr = current_block->variables[var.name];
 462         if(!ptr)
 463                 ptr = &var;
 464         else if(!current_block->parent && ptr->interface==var.interface && ptr->type==var.type)
 465         {
 466                 if(ptr->source==BUILTIN_SOURCE)
 467                         redeclared_builtins.push_back(&var);
 468                 else
 469                         stage->diagnostics.push_back(Diagnostic(Diagnostic::WARN, var.source, var.line,
 470                                 format("Redeclaring non-builtin variable '%s' is deprecated", var.name)));
 471
 472                 if(var.init_expression)
 473                         ptr->init_expression = var.init_expression;
 474                 if(var.layout)
 475                 {
 476                         if(ptr->layout)
 477                                 merge_layouts(*ptr->layout, *var.layout);
 478                         else
 479                                 ptr->layout = var.layout;
 480                 }
 481                 nodes_to_remove.insert(&var);
 482
 483                 r_any_resolved = true;
 484         }
 485 }
 486
 487 void VariableResolver::visit(InterfaceBlock &iface)
 488 {
 489         /* Block names can be reused in different interfaces.  Prefix the name with
 490         the first character of the interface to avoid conflicts. */
 491         stage->interface_blocks.insert(make_pair(iface.interface+iface.name, &iface));
 492         if(!iface.instance_name.empty())
 493                 stage->interface_blocks.insert(make_pair("_"+iface.instance_name, &iface));
 494
 495         TraversingVisitor::visit(iface);
 496 }
 497
 498
 499 ExpressionResolver::ExpressionResolver():
 500         stage(0),
 501         r_any_resolved(false)
 502 { }
 503
 504 bool ExpressionResolver::apply(Stage &s)
 505 {
 506         stage = &s;
 507         r_any_resolved = false;
 508         s.content.visit(*this);
 509         return r_any_resolved;
 510 }
 511
 512 bool ExpressionResolver::is_scalar(BasicTypeDeclaration &type)
 513 {
 514         return (type.kind==BasicTypeDeclaration::INT || type.kind==BasicTypeDeclaration::FLOAT);
 515 }
 516
 517 bool ExpressionResolver::is_vector_or_matrix(BasicTypeDeclaration &type)
 518 {
 519         return (type.kind==BasicTypeDeclaration::VECTOR || type.kind==BasicTypeDeclaration::MATRIX);
 520 }
 521
 522 BasicTypeDeclaration *ExpressionResolver::get_element_type(BasicTypeDeclaration &type)
 523 {
 524         if(is_vector_or_matrix(type) || type.kind==BasicTypeDeclaration::ARRAY)
 525         {
 526                 BasicTypeDeclaration *basic_base = dynamic_cast<BasicTypeDeclaration *>(type.base_type);
 527                 return (basic_base ? get_element_type(*basic_base) : 0);
 528         }
 529         else
 530                 return &type;
 531 }
 532
 533 bool ExpressionResolver::can_convert(BasicTypeDeclaration &from, BasicTypeDeclaration &to)
 534 {
 535         if(from.kind==BasicTypeDeclaration::INT && to.kind==BasicTypeDeclaration::FLOAT)
 536                 return from.size<=to.size;
 537         else if(from.kind!=to.kind)
 538                 return false;
 539         else if((from.kind==BasicTypeDeclaration::VECTOR || from.kind==BasicTypeDeclaration::MATRIX) && from.size==to.size)
 540         {
 541                 BasicTypeDeclaration *from_base = dynamic_cast<BasicTypeDeclaration *>(from.base_type);
 542                 BasicTypeDeclaration *to_base = dynamic_cast<BasicTypeDeclaration *>(to.base_type);
 543                 return (from_base && to_base && can_convert(*from_base, *to_base));
 544         }
 545         else
 546                 return false;
 547 }
 548
 549 ExpressionResolver::Compatibility ExpressionResolver::get_compatibility(BasicTypeDeclaration &left, BasicTypeDeclaration &right)
 550 {
 551         if(&left==&right)
 552                 return SAME_TYPE;
 553         else if(can_convert(left, right))
 554                 return LEFT_CONVERTIBLE;
 555         else if(can_convert(right, left))
 556                 return RIGHT_CONVERTIBLE;
 557         else
 558                 return NOT_COMPATIBLE;
 559 }
 560
 561 BasicTypeDeclaration *ExpressionResolver::find_type(BasicTypeDeclaration::Kind kind, unsigned size)
 562 {
 563         for(vector<BasicTypeDeclaration *>::const_iterator i=basic_types.begin(); i!=basic_types.end(); ++i)
 564                 if((*i)->kind==kind && (*i)->size==size)
 565                         return *i;
 566         return 0;
 567 }
 568
 569 BasicTypeDeclaration *ExpressionResolver::find_type(BasicTypeDeclaration &elem_type, BasicTypeDeclaration::Kind kind, unsigned size)
 570 {
 571         for(vector<BasicTypeDeclaration *>::const_iterator i=basic_types.begin(); i!=basic_types.end(); ++i)
 572                 if(get_element_type(**i)==&elem_type && (*i)->kind==kind && (*i)->size==size)
 573                         return *i;
 574         return 0;
 575 }
 576
 577 void ExpressionResolver::convert_to(RefPtr<Expression> &expr, BasicTypeDeclaration &type)
 578 {
 579         RefPtr<FunctionCall> call = new FunctionCall;
 580         call->name = type.name;
 581         call->constructor = true;
 582         call->arguments.push_back(0);
 583         call->arguments.back() = expr;
 584         call->type = &type;
 585         expr = call;
 586 }
 587
 588 bool ExpressionResolver::convert_to_element(RefPtr<Expression> &expr, BasicTypeDeclaration &elem_type)
 589 {
 590         if(BasicTypeDeclaration *expr_basic = dynamic_cast<BasicTypeDeclaration *>(expr->type))
 591         {
 592                 BasicTypeDeclaration *to_type = &elem_type;
 593                 if(is_vector_or_matrix(*expr_basic))
 594                         to_type = find_type(elem_type, expr_basic->kind, expr_basic->size);
 595                 if(to_type)
 596                 {
 597                         convert_to(expr, *to_type);
 598                         return true;
 599                 }
 600         }
 601
 602         return false;
 603 }
 604
 605 void ExpressionResolver::resolve(Expression &expr, TypeDeclaration *type, bool lvalue)
 606 {
 607         r_any_resolved |= (type!=expr.type || lvalue!=expr.lvalue);
 608         expr.type = type;
 609         expr.lvalue = lvalue;
 610 }
 611
 612 void ExpressionResolver::visit(Literal &literal)
 613 {
 614         if(literal.value.check_type<bool>())
 615                 resolve(literal, find_type(BasicTypeDeclaration::BOOL, 1), false);
 616         else if(literal.value.check_type<int>())
 617                 resolve(literal, find_type(BasicTypeDeclaration::INT, 32), false);
 618         else if(literal.value.check_type<float>())
 619                 resolve(literal, find_type(BasicTypeDeclaration::FLOAT, 32), false);
 620 }
 621
 622 void ExpressionResolver::visit(VariableReference &var)
 623 {
 624         if(var.declaration)
 625                 resolve(var, var.declaration->type_declaration, true);
 626 }
 627
 628 void ExpressionResolver::visit(InterfaceBlockReference &iface)
 629 {
 630         if(iface.declaration)
 631                 resolve(iface, iface.declaration->type_declaration, true);
 632 }
 633
 634 void ExpressionResolver::visit(MemberAccess &memacc)
 635 {
 636         TraversingVisitor::visit(memacc);
 637
 638         if(memacc.declaration)
 639                 resolve(memacc, memacc.declaration->type_declaration, memacc.left->lvalue);
 640 }
 641
 642 void ExpressionResolver::visit(Swizzle &swizzle)
 643 {
 644         TraversingVisitor::visit(swizzle);
 645
 646         if(BasicTypeDeclaration *left_basic = dynamic_cast<BasicTypeDeclaration *>(swizzle.left->type))
 647         {
 648                 BasicTypeDeclaration *left_elem = get_element_type(*left_basic);
 649                 if(swizzle.count==1)
 650                         resolve(swizzle, left_elem, swizzle.left->lvalue);
 651                 else if(left_basic->kind==BasicTypeDeclaration::VECTOR && left_elem)
 652                         resolve(swizzle, find_type(*left_elem, left_basic->kind, swizzle.count), swizzle.left->lvalue);
 653         }
 654 }
 655
 656 void ExpressionResolver::visit(UnaryExpression &unary)
 657 {
 658         TraversingVisitor::visit(unary);
 659
 660         BasicTypeDeclaration *basic = dynamic_cast<BasicTypeDeclaration *>(unary.expression->type);
 661         if(!basic)
 662                 return;
 663
 664         char oper = unary.oper->token[0];
 665         if(oper=='!')
 666         {
 667                 if(basic->kind!=BasicTypeDeclaration::BOOL)
 668                         return;
 669         }
 670         else if(oper=='~')
 671         {
 672                 if(basic->kind!=BasicTypeDeclaration::INT)
 673                         return;
 674         }
 675         else if(oper=='+' || oper=='-')
 676         {
 677                 BasicTypeDeclaration *elem = get_element_type(*basic);
 678                 if(!elem || !is_scalar(*elem))
 679                         return;
 680         }
 681         resolve(unary, basic, unary.expression->lvalue);
 682 }
 683
 684 void ExpressionResolver::visit(BinaryExpression &binary, bool assign)
 685 {
 686         /* Binary operators are only defined for basic types (not for image or
 687         structure types). */
 688         BasicTypeDeclaration *basic_left = dynamic_cast<BasicTypeDeclaration *>(binary.left->type);
 689         BasicTypeDeclaration *basic_right = dynamic_cast<BasicTypeDeclaration *>(binary.right->type);
 690         if(!basic_left || !basic_right)
 691                 return;
 692
 693         char oper = binary.oper->token[0];
 694         if(oper=='[')
 695         {
 696                 /* Subscripting operates on vectors, matrices and arrays, and the right
 697                 operand must be an integer. */
 698                 if((!is_vector_or_matrix(*basic_left) && basic_left->kind!=BasicTypeDeclaration::ARRAY) || basic_right->kind!=BasicTypeDeclaration::INT)
 699                         return;
 700
 701                 resolve(binary, basic_left->base_type, binary.left->lvalue);
 702                 return;
 703         }
 704         else if(basic_left->kind==BasicTypeDeclaration::ARRAY || basic_right->kind==BasicTypeDeclaration::ARRAY)
 705                 // No other binary operator can be used with arrays.
 706                 return;
 707
 708         BasicTypeDeclaration *elem_left = get_element_type(*basic_left);
 709         BasicTypeDeclaration *elem_right = get_element_type(*basic_right);
 710         if(!elem_left || !elem_right)
 711                 return;
 712
 713         Compatibility compat = get_compatibility(*basic_left, *basic_right);
 714         Compatibility elem_compat = get_compatibility(*elem_left, *elem_right);
 715         if(elem_compat==NOT_COMPATIBLE)
 716                 return;
 717         if(assign && (compat==LEFT_CONVERTIBLE || elem_compat==LEFT_CONVERTIBLE))
 718                 return;
 719
 720         TypeDeclaration *type = 0;
 721         char oper2 = binary.oper->token[1];
 722         if((oper=='<' && oper2!='<') || (oper=='>' && oper2!='>'))
 723         {
 724                 /* Relational operators compare two scalar integer or floating-point
 725                 values. */
 726                 if(!is_scalar(*elem_left) || !is_scalar(*elem_right) || compat==NOT_COMPATIBLE)
 727                         return;
 728
 729                 type = find_type(BasicTypeDeclaration::BOOL, 1);
 730         }
 731         else if((oper=='=' || oper=='!') && oper2=='=')
 732         {
 733                 // Equality comparison can be done on any compatible types.
 734                 if(compat==NOT_COMPATIBLE)
 735                         return;
 736
 737                 type = find_type(BasicTypeDeclaration::BOOL, 1);
 738         }
 739         else if(oper2=='&' || oper2=='|' || oper2=='^')
 740         {
 741                 // Logical operators can only be applied to booleans.
 742                 if(basic_left->kind!=BasicTypeDeclaration::BOOL || basic_right->kind!=BasicTypeDeclaration::BOOL)
 743                         return;
 744
 745                 type = basic_left;
 746         }
 747         else if((oper=='&' || oper=='|' || oper=='^' || oper=='%') && !oper2)
 748         {
 749                 // Bitwise operators and modulo can only be applied to integers.
 750                 if(basic_left->kind!=BasicTypeDeclaration::INT || basic_right->kind!=BasicTypeDeclaration::INT)
 751                         return;
 752
 753                 type = (compat==LEFT_CONVERTIBLE ? basic_right : basic_left);
 754         }
 755         else if((oper=='<' || oper=='>') && oper2==oper)
 756         {
 757                 // Shifts apply to integer scalars and vectors, with some restrictions.
 758                 if(elem_left->kind!=BasicTypeDeclaration::INT || elem_right->kind!=BasicTypeDeclaration::INT)
 759                         return;
 760                 unsigned left_size = (basic_left->kind==BasicTypeDeclaration::INT ? 1 : basic_left->kind==BasicTypeDeclaration::VECTOR ? basic_left->size : 0);
 761                 unsigned right_size = (basic_right->kind==BasicTypeDeclaration::INT ? 1 : basic_right->kind==BasicTypeDeclaration::VECTOR ? basic_right->size : 0);
 762                 if(!left_size || (left_size==1 && right_size!=1) || (left_size>1 && right_size!=1 && right_size!=left_size))
 763                         return;
 764
 765                 type = basic_left;
 766                 // Don't perform conversion even if the operands are of different sizes.
 767                 compat = SAME_TYPE;
 768         }
 769         else if(oper=='+' || oper=='-' || oper=='*' || oper=='/')
 770         {
 771                 // Arithmetic operators require scalar elements.
 772                 if(!is_scalar(*elem_left) || !is_scalar(*elem_right))
 773                         return;
 774
 775                 if(oper=='*' && is_vector_or_matrix(*basic_left) && is_vector_or_matrix(*basic_right) &&
 776                         (basic_left->kind==BasicTypeDeclaration::MATRIX || basic_right->kind==BasicTypeDeclaration::MATRIX))
 777                 {
 778                         /* Multiplication has special rules when at least one operand is a
 779                         matrix and the other is a vector or a matrix. */
 780                         unsigned left_columns = basic_left->size&0xFFFF;
 781                         unsigned right_rows = basic_right->size;
 782                         if(basic_right->kind==BasicTypeDeclaration::MATRIX)
 783                                 right_rows >>= 16;
 784                         if(left_columns!=right_rows)
 785                                 return;
 786
 787                         BasicTypeDeclaration *elem_result = (elem_compat==LEFT_CONVERTIBLE ? elem_right : elem_left);
 788
 789                         if(basic_left->kind==BasicTypeDeclaration::VECTOR)
 790                                 type = find_type(*elem_result, BasicTypeDeclaration::VECTOR, basic_right->size&0xFFFF);
 791                         else if(basic_right->kind==BasicTypeDeclaration::VECTOR)
 792                                 type = find_type(*elem_result, BasicTypeDeclaration::VECTOR, basic_left->size>>16);
 793                         else
 794                                 type = find_type(*elem_result, BasicTypeDeclaration::MATRIX, (basic_left->size&0xFFFF0000)|(basic_right->size&0xFFFF));
 795                 }
 796                 else if(compat==NOT_COMPATIBLE)
 797                 {
 798                         // Arithmetic between scalars and matrices or vectors is supported.
 799                         if(is_scalar(*basic_left) && is_vector_or_matrix(*basic_right))
 800                                 type = (elem_compat==RIGHT_CONVERTIBLE ? find_type(*elem_left, basic_right->kind, basic_right->size) : basic_right);
 801                         else if(is_vector_or_matrix(*basic_left) && is_scalar(*basic_right))
 802                                 type = (elem_compat==LEFT_CONVERTIBLE ? find_type(*elem_right, basic_left->kind, basic_left->size) : basic_left);
 803                         else
 804                                 return;
 805                 }
 806                 else if(compat==LEFT_CONVERTIBLE)
 807                         type = basic_right;
 808                 else
 809                         type = basic_left;
 810         }
 811         else
 812                 return;
 813
 814         if(assign && type!=basic_left)
 815                 return;
 816
 817         bool converted = true;
 818         if(compat==LEFT_CONVERTIBLE)
 819                 convert_to(binary.left, *basic_right);
 820         else if(compat==RIGHT_CONVERTIBLE)
 821                 convert_to(binary.right, *basic_left);
 822         else if(elem_compat==LEFT_CONVERTIBLE)
 823                 converted = convert_to_element(binary.left, *elem_right);
 824         else if(elem_compat==RIGHT_CONVERTIBLE)
 825                 converted = convert_to_element(binary.right, *elem_left);
 826
 827         if(!converted)
 828                 type = 0;
 829
 830         resolve(binary, type, assign);
 831 }
 832
 833 void ExpressionResolver::visit(BinaryExpression &binary)
 834 {
 835         TraversingVisitor::visit(binary);
 836         visit(binary, false);
 837 }
 838
 839 void ExpressionResolver::visit(Assignment &assign)
 840 {
 841         TraversingVisitor::visit(assign);
 842
 843         if(assign.oper->token[0]!='=')
 844                 return visit(assign, true);
 845         else if(assign.left->type!=assign.right->type)
 846         {
 847                 BasicTypeDeclaration *basic_left = dynamic_cast<BasicTypeDeclaration *>(assign.left->type);
 848                 BasicTypeDeclaration *basic_right = dynamic_cast<BasicTypeDeclaration *>(assign.right->type);
 849                 if(!basic_left || !basic_right)
 850                         return;
 851
 852                 Compatibility compat = get_compatibility(*basic_left, *basic_right);
 853                 if(compat==RIGHT_CONVERTIBLE)
 854                         convert_to(assign.right, *basic_left);
 855                 else if(compat!=SAME_TYPE)
 856                         return;
 857         }
 858
 859         resolve(assign, assign.left->type, true);
 860 }
 861
 862 void ExpressionResolver::visit(TernaryExpression &ternary)
 863 {
 864         TraversingVisitor::visit(ternary);
 865
 866         BasicTypeDeclaration *basic_cond = dynamic_cast<BasicTypeDeclaration *>(ternary.condition->type);
 867         if(!basic_cond || basic_cond->kind!=BasicTypeDeclaration::BOOL)
 868                 return;
 869
 870         TypeDeclaration *type = 0;
 871         if(ternary.true_expr->type==ternary.false_expr->type)
 872                 type = ternary.true_expr->type;
 873         else
 874         {
 875                 BasicTypeDeclaration *basic_true = dynamic_cast<BasicTypeDeclaration *>(ternary.true_expr->type);
 876                 BasicTypeDeclaration *basic_false = dynamic_cast<BasicTypeDeclaration *>(ternary.false_expr->type);
 877                 Compatibility compat = get_compatibility(*basic_true, *basic_false);
 878                 if(compat==NOT_COMPATIBLE)
 879                         return;
 880
 881                 type = (compat==LEFT_CONVERTIBLE ? basic_true : basic_false);
 882
 883                 if(compat==LEFT_CONVERTIBLE)
 884                         convert_to(ternary.true_expr, *basic_false);
 885                 else if(compat==RIGHT_CONVERTIBLE)
 886                         convert_to(ternary.false_expr, *basic_true);
 887         }
 888
 889         resolve(ternary, type, false);
 890 }
 891
 892 void ExpressionResolver::visit(FunctionCall &call)
 893 {
 894         TraversingVisitor::visit(call);
 895
 896         TypeDeclaration *type = 0;
 897         if(call.declaration)
 898                 type = call.declaration->return_type_declaration;
 899         else if(call.constructor)
 900         {
 901                 map<string, TypeDeclaration *>::const_iterator i=stage->types.find(call.name);
 902                 type = (i!=stage->types.end() ? i->second : 0);
 903         }
 904         resolve(call, type, false);
 905 }
 906
 907 void ExpressionResolver::visit(BasicTypeDeclaration &type)
 908 {
 909         basic_types.push_back(&type);
 910 }
 911
 912 void ExpressionResolver::visit(VariableDeclaration &var)
 913 {
 914         TraversingVisitor::visit(var);
 915         if(!var.init_expression)
 916                 return;
 917
 918         BasicTypeDeclaration *var_basic = dynamic_cast<BasicTypeDeclaration *>(var.type_declaration);
 919         BasicTypeDeclaration *init_basic = dynamic_cast<BasicTypeDeclaration *>(var.init_expression->type);
 920         if(!var_basic || !init_basic)
 921                 return;
 922
 923         Compatibility compat = get_compatibility(*var_basic, *init_basic);
 924         if(compat==RIGHT_CONVERTIBLE)
 925                 convert_to(var.init_expression, *var_basic);
 926 }
 927
 928
 929 bool FunctionResolver::apply(Stage &s)
 930 {
 931         stage = &s;
 932         s.functions.clear();
 933         r_any_resolved = false;
 934         s.content.visit(*this);
 935         return r_any_resolved;
 936 }
 937
 938 void FunctionResolver::visit(FunctionCall &call)
 939 {
 940         string arg_types;
 941         bool has_signature = true;
 942         for(NodeArray<Expression>::const_iterator i=call.arguments.begin(); (has_signature && i!=call.arguments.end()); ++i)
 943         {
 944                 if((*i)->type)
 945                         append(arg_types, ",", (*i)->type->name);
 946                 else
 947                         has_signature = false;
 948         }
 949
 950         FunctionDeclaration *declaration = 0;
 951         if(has_signature)
 952         {
 953                 map<string, FunctionDeclaration *>::iterator i = stage->functions.find(format("%s(%s)", call.name, arg_types));
 954                 declaration = (i!=stage->functions.end() ? i->second : 0);
 955         }
 956         r_any_resolved |= (declaration!=call.declaration);
 957         call.declaration = declaration;
 958
 959         TraversingVisitor::visit(call);
 960 }
 961
 962 void FunctionResolver::visit(FunctionDeclaration &func)
 963 {
 964         if(func.signature.empty())
 965         {
 966                 string param_types;
 967                 for(NodeArray<VariableDeclaration>::const_iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 968                 {
 969                         if((*i)->type_declaration)
 970                                 append(param_types, ",", (*i)->type_declaration->name);
 971                         else
 972                                 return;
 973                 }
 974                 func.signature = format("(%s)", param_types);
 975                 r_any_resolved = true;
 976         }
 977
 978         string key = func.name+func.signature;
 979         FunctionDeclaration *&stage_decl = stage->functions[key];
 980         vector<FunctionDeclaration *> &decls = declarations[key];
 981         if(func.definition==&func)
 982         {
 983                 if(stage_decl && stage_decl->definition)
 984                 {
 985                         if(!func.overrd)
 986                                 stage->diagnostics.push_back(Diagnostic(Diagnostic::WARN, func.source, func.line,
 987                                         format("Overriding function '%s' without the override keyword is deprecated", key)));
 988                         if(!stage_decl->definition->virtua)
 989                                 stage->diagnostics.push_back(Diagnostic(Diagnostic::WARN, func.source, func.line,
 990                                         format("Overriding function '%s' not declared as virtual is deprecated", key)));
 991                 }
 992                 stage_decl = &func;
 993
 994                 // Set all previous declarations to use this definition.
 995                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 996                 {
 997                         r_any_resolved |= (func.definition!=(*i)->definition);
 998                         (*i)->definition = func.definition;
 999                         (*i)->body.body.clear();
1000                 }
1001         }
1002         else
1003         {
1004                 FunctionDeclaration *definition = (stage_decl ? stage_decl->definition : 0);
1005                 r_any_resolved |= (definition!=func.definition);
1006                 func.definition = definition;
1007
1008                 if(!stage_decl)
1009                         stage_decl = &func;
1010         }
1011         decls.push_back(&func);
1012
1013         TraversingVisitor::visit(func);
1014 }
1015
1016
1017 InterfaceGenerator::InterfaceGenerator():
1018         stage(0),
1019         function_scope(false),
1020         copy_block(false),
1021         iface_target_block(0)
1022 { }
1023
1024 string InterfaceGenerator::get_out_prefix(Stage::Type type)
1025 {
1026         if(type==Stage::VERTEX)
1027                 return "_vs_out_";
1028         else if(type==Stage::GEOMETRY)
1029                 return "_gs_out_";
1030         else
1031                 return string();
1032 }
1033
1034 void InterfaceGenerator::apply(Stage &s)
1035 {
1036         stage = &s;
1037         iface_target_block = &stage->content;
1038         if(stage->previous)
1039                 in_prefix = get_out_prefix(stage->previous->type);
1040         out_prefix = get_out_prefix(stage->type);
1041         s.content.visit(*this);
1042         NodeRemover().apply(s, nodes_to_remove);
1043 }
1044
1045 void InterfaceGenerator::visit(Block &block)
1046 {
1047         SetForScope<Block *> set_block(current_block, &block);
1048         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
1049         {
1050                 assignment_insert_point = i;
1051                 if(&block==&stage->content)
1052                         iface_insert_point = i;
1053
1054                 (*i)->visit(*this);
1055         }
1056 }
1057
1058 string InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
1059 {
1060         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
1061         return prefix+name.substr(offset);
1062 }
1063
1064 VariableDeclaration *InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
1065 {
1066         if(stage->content.variables.count(name))
1067                 return 0;
1068
1069         if(stage->type==Stage::GEOMETRY && !copy_block && var.interface=="out" && var.array)
1070                 return 0;
1071
1072         VariableDeclaration* iface_var = new VariableDeclaration;
1073         iface_var->sampling = var.sampling;
1074         iface_var->interface = iface;
1075         iface_var->type = var.type;
1076         iface_var->name = name;
1077         /* Geometry shader inputs are always arrays.  But if we're bringing in an
1078         entire block, the array is on the block and not individual variables. */
1079         if(stage->type==Stage::GEOMETRY && !copy_block)
1080                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
1081         else
1082                 iface_var->array = var.array;
1083         if(iface_var->array)
1084                 iface_var->array_size = var.array_size;
1085         if(iface=="in")
1086         {
1087                 iface_var->layout = var.layout;
1088                 iface_var->linked_declaration = &var;
1089                 var.linked_declaration = iface_var;
1090         }
1091
1092         iface_target_block->body.insert(iface_insert_point, iface_var);
1093         iface_target_block->variables.insert(make_pair(name, iface_var));
1094         if(iface_target_block==&stage->content && iface=="in")
1095                 declared_inputs.push_back(iface_var);
1096
1097         return iface_var;
1098 }
1099
1100 InterfaceBlock *InterfaceGenerator::generate_interface(InterfaceBlock &out_block)
1101 {
1102         if(stage->interface_blocks.count("in"+out_block.name))
1103                 return 0;
1104
1105         InterfaceBlock *in_block = new InterfaceBlock;
1106         in_block->interface = "in";
1107         in_block->name = out_block.name;
1108         in_block->members = new Block;
1109         in_block->instance_name = out_block.instance_name;
1110         if(stage->type==Stage::GEOMETRY)
1111                 in_block->array = true;
1112         else
1113                 in_block->array = out_block.array;
1114         in_block->linked_block = &out_block;
1115         out_block.linked_block = in_block;
1116
1117         {
1118                 SetFlag set_copy(copy_block, true);
1119                 SetForScope<Block *> set_target(iface_target_block, in_block->members.get());
1120                 SetForScope<NodeList<Statement>::iterator> set_ins_pt(iface_insert_point, in_block->members->body.end());
1121                 if(out_block.struct_declaration)
1122                         out_block.struct_declaration->members.visit(*this);
1123                 else if(out_block.members)
1124                         out_block.members->visit(*this);
1125         }
1126
1127         iface_target_block->body.insert(iface_insert_point, in_block);
1128         stage->interface_blocks.insert(make_pair("in"+in_block->name, in_block));
1129         if(!in_block->instance_name.empty())
1130                 stage->interface_blocks.insert(make_pair("_"+in_block->instance_name, in_block));
1131
1132         SetFlag set_scope(function_scope, false);
1133         SetForScope<Block *> set_block(current_block, &stage->content);
1134         in_block->visit(*this);
1135
1136         return in_block;
1137 }
1138
1139 ExpressionStatement &InterfaceGenerator::insert_assignment(const string &left, Expression *right)
1140 {
1141         Assignment *assign = new Assignment;
1142         VariableReference *ref = new VariableReference;
1143         ref->name = left;
1144         assign->left = ref;
1145         assign->oper = &Operator::get_operator("=", Operator::BINARY);
1146         assign->right = right;
1147
1148         ExpressionStatement *stmt = new ExpressionStatement;
1149         stmt->expression = assign;
1150         current_block->body.insert(assignment_insert_point, stmt);
1151         stmt->visit(*this);
1152
1153         return *stmt;
1154 }
1155
1156 void InterfaceGenerator::visit(VariableReference &var)
1157 {
1158         if(var.declaration || !stage->previous)
1159                 return;
1160         /* Don't pull a variable from previous stage if we just generated an output
1161         interface in this stage */
1162         if(stage->content.variables.count(var.name))
1163                 return;
1164
1165         const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
1166         map<string, VariableDeclaration *>::const_iterator i = prev_vars.find(var.name);
1167         if(i==prev_vars.end() || i->second->interface!="out")
1168                 i = prev_vars.find(in_prefix+var.name);
1169         if(i!=prev_vars.end() && i->second->interface=="out")
1170         {
1171                 if(stage->type==Stage::GEOMETRY && i->second->array)
1172                         stage->diagnostics.push_back(Diagnostic(Diagnostic::WARN, var.source, var.line,
1173                                 format("Can't access '%s' through automatic interface because it's an array", var.name)));
1174                 else
1175                 {
1176                         generate_interface(*i->second, "in", i->second->name);
1177                         var.name = i->second->name;
1178                 }
1179                 return;
1180         }
1181
1182         const map<string, InterfaceBlock *> &prev_blocks = stage->previous->interface_blocks;
1183         map<string, InterfaceBlock *>::const_iterator j = prev_blocks.find("_"+var.name);
1184         if(j!=prev_blocks.end() && j->second->interface=="out")
1185         {
1186                 generate_interface(*j->second);
1187                 /* Let VariableResolver convert the variable reference into an interface
1188                 block reference. */
1189                 return;
1190         }
1191
1192         for(j=prev_blocks.begin(); j!=prev_blocks.end(); ++j)
1193                 if(j->second->instance_name.empty() && j->second->struct_declaration)
1194                 {
1195                         const map<string, VariableDeclaration *> &iface_vars = j->second->struct_declaration->members.variables;
1196                         i = iface_vars.find(var.name);
1197                         if(i!=iface_vars.end())
1198                         {
1199                                 generate_interface(*j->second);
1200                                 return;
1201                         }
1202                 }
1203 }
1204
1205 void InterfaceGenerator::visit(VariableDeclaration &var)
1206 {
1207         if(copy_block)
1208                 generate_interface(var, "in", var.name);
1209         else if(var.interface=="out")
1210         {
1211                 /* For output variables in function scope, generate a global interface
1212                 and replace the local declaration with an assignment. */
1213                 VariableDeclaration *out_var = 0;
1214                 if(function_scope && (out_var=generate_interface(var, "out", var.name)))
1215                 {
1216                         out_var->source = var.source;
1217                         out_var->line = var.line;
1218                         nodes_to_remove.insert(&var);
1219                         if(var.init_expression)
1220                         {
1221                                 ExpressionStatement &stmt = insert_assignment(var.name, var.init_expression->clone());
1222                                 stmt.source = var.source;
1223                                 stmt.line = var.line;
1224                                 return;
1225                         }
1226                 }
1227         }
1228         else if(var.interface=="in" && current_block==&stage->content)
1229         {
1230                 if(var.name.compare(0, 3, "gl_"))
1231                         declared_inputs.push_back(&var);
1232
1233                 /* Try to link input variables in global scope with output variables from
1234                 previous stage. */
1235                 if(!var.linked_declaration && stage->previous)
1236                 {
1237                         const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
1238                         map<string, VariableDeclaration *>::const_iterator i = prev_vars.find(var.name);
1239                         if(i!=prev_vars.end() && i->second->interface=="out")
1240                         {
1241                                 var.linked_declaration = i->second;
1242                                 i->second->linked_declaration = &var;
1243                         }
1244                 }
1245         }
1246
1247         TraversingVisitor::visit(var);
1248 }
1249
1250 void InterfaceGenerator::visit(InterfaceBlock &iface)
1251 {
1252         if(iface.interface=="in")
1253         {
1254                 /* Try to link input blocks with output blocks sharing the same block
1255                 name from previous stage. */
1256                 if(!iface.linked_block && stage->previous)
1257                 {
1258                         const map<string, InterfaceBlock *> &prev_blocks = stage->previous->interface_blocks;
1259                         map<string, InterfaceBlock *>::const_iterator i = prev_blocks.find("out"+iface.name);
1260                         if(i!=prev_blocks.end())
1261                         {
1262                                 iface.linked_block = i->second;
1263                                 i->second->linked_block = &iface;
1264                         }
1265                 }
1266         }
1267
1268         TraversingVisitor::visit(iface);
1269 }
1270
1271 void InterfaceGenerator::visit(FunctionDeclaration &func)
1272 {
1273         SetFlag set_scope(function_scope, true);
1274         // Skip parameters because they're not useful here
1275         func.body.visit(*this);
1276 }
1277
1278 void InterfaceGenerator::visit(Passthrough &pass)
1279 {
1280         // Pass through all input variables declared so far.
1281         vector<VariableDeclaration *> pass_vars = declared_inputs;
1282
1283         if(stage->previous)
1284         {
1285                 const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
1286                 for(map<string, VariableDeclaration *>::const_iterator i=prev_vars.begin(); i!=prev_vars.end(); ++i)
1287                 {
1288                         if(i->second->interface!="out")
1289                                 continue;
1290
1291                         /* Pass through output variables from the previous stage, but only
1292                         those which are not already linked to an input here. */
1293                         if(!i->second->linked_declaration && generate_interface(*i->second, "in", i->second->name))
1294                                 pass_vars.push_back(i->second);
1295                 }
1296         }
1297
1298         if(stage->type==Stage::GEOMETRY)
1299         {
1300                 /* Special case for geometry shader: copy gl_Position from input to
1301                 output. */
1302                 InterfaceBlockReference *ref = new InterfaceBlockReference;
1303                 ref->name = "gl_in";
1304
1305                 BinaryExpression *subscript = new BinaryExpression;
1306                 subscript->left = ref;
1307                 subscript->oper = &Operator::get_operator("[", Operator::BINARY);
1308                 subscript->right = pass.subscript;
1309
1310                 MemberAccess *memacc = new MemberAccess;
1311                 memacc->left = subscript;
1312                 memacc->member = "gl_Position";
1313
1314                 insert_assignment("gl_Position", memacc);
1315         }
1316
1317         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
1318         {
1319                 string out_name = change_prefix((*i)->name, out_prefix);
1320                 generate_interface(**i, "out", out_name);
1321
1322                 VariableReference *ref = new VariableReference;
1323                 ref->name = (*i)->name;
1324                 if(pass.subscript)
1325                 {
1326                         BinaryExpression *subscript = new BinaryExpression;
1327                         subscript->left = ref;
1328                         subscript->oper = &Operator::get_operator("[", Operator::BINARY);
1329                         subscript->right = pass.subscript;
1330                         insert_assignment(out_name, subscript);
1331                 }
1332                 else
1333                         insert_assignment(out_name, ref);
1334         }
1335
1336         nodes_to_remove.insert(&pass);
1337 }
1338
1339 } // namespace SL
1340 } // namespace GL
1341 } // namespace Msp