source/glsl/parser.cpp

   1 #include <msp/core/raii.h>
   2 #include <msp/strings/format.h>
   3 #include <msp/strings/regex.h>
   4 #include <msp/strings/utils.h>
   5 #include "builtin.h"
   6 #include "glsl_error.h"
   7 #include "parser.h"
   8
   9 #undef interface
  10
  11 using namespace std;
  12
  13 namespace Msp {
  14 namespace GL {
  15 namespace SL {
  16
  17 Parser::Parser():
  18         preprocessor(tokenizer),
  19         module(0)
  20 {
  21         tokenizer.signal_preprocess.connect(sigc::mem_fun(&preprocessor, &Preprocessor::preprocess));
  22         preprocessor.signal_version.connect(sigc::mem_fun(this, &Parser::set_required_version));
  23         preprocessor.signal_source.connect(sigc::mem_fun(this, &Parser::source_reference));
  24         preprocessor.signal_stage_change.connect(sigc::mem_fun(this, &Parser::stage_change));
  25         preprocessor.signal_line.connect(sigc::mem_fun(this, &Parser::line_change));
  26 }
  27
  28 Parser::~Parser()
  29 {
  30         delete module;
  31 }
  32
  33 Module &Parser::parse(const string &s, const string &n, int i)
  34 {
  35         source = s;
  36         parse_source(n, i);
  37         return *module;
  38 }
  39
  40 Module &Parser::parse(IO::Base &io, const string &n, int i)
  41 {
  42         source = string();
  43         while(!io.eof())
  44         {
  45                 char buffer[4096];
  46                 unsigned len = io.read(buffer, sizeof(buffer));
  47                 source.append(buffer, len);
  48         }
  49         parse_source(n, i);
  50         return *module;
  51 }
  52
  53 void Parser::parse_source(const string &name, int index)
  54 {
  55         delete module;
  56         module = new Module;
  57
  58         cur_stage = &module->shared;
  59         base_index = index;
  60         source_index = index;
  61         if(index>=0)
  62                 source_reference(1, name);
  63
  64         // TODO Need to somehow get type names from imports
  65         if(const Stage *builtin = get_builtins(Stage::SHARED))
  66         {
  67                 for(map<string, TypeDeclaration *>::const_iterator i=builtin->types.begin(); i!=builtin->types.end(); ++i)
  68                         declared_types.insert(i->first);
  69         }
  70         else
  71         {
  72                 declared_types.insert("void");
  73                 declared_types.insert("bool");
  74                 declared_types.insert("int");
  75                 declared_types.insert("float");
  76         }
  77
  78         tokenizer.begin(source, name);
  79         allow_stage_change = true;
  80         while(!tokenizer.peek_token().empty())
  81                 if(RefPtr<Statement> statement = parse_with_recovery(&Parser::parse_global_declaration))
  82                         cur_stage->content.body.push_back(statement);
  83
  84         if(!errors.empty())
  85                 throw invalid_shader_source(join(errors.begin(), errors.end(), "\n"));
  86 }
  87
  88 void Parser::set_required_version(const Version &ver)
  89 {
  90         cur_stage->required_features.glsl_version = ver;
  91 }
  92
  93 void Parser::source_reference(unsigned index, const string &name)
  94 {
  95         if(index<1 || base_index<0)
  96                 throw invalid_shader_source(tokenizer.get_location(), "Invalid source reference");
  97
  98         module->source_map.set_name(base_index+index-1, name);
  99 }
 100
 101 void Parser::stage_change(Stage::Type stage)
 102 {
 103         if(!allow_stage_change)
 104                 throw invalid_shader_source(tokenizer.get_location(), "Changing stage not allowed here");
 105         else if(stage<=cur_stage->type)
 106                 throw invalid_shader_source(tokenizer.get_location(), "Stage '%s' not allowed here", Stage::get_stage_name(stage));
 107
 108         module->stages.push_back(stage);
 109
 110         if(cur_stage->type!=Stage::SHARED)
 111                 module->stages.back().previous = cur_stage;
 112         cur_stage = &module->stages.back();
 113 }
 114
 115 void Parser::line_change(int index, unsigned line)
 116 {
 117         if(index>0)
 118                 source_index = base_index+index-1;
 119         else if(index==0)
 120                 source_index = 0;
 121         else
 122                 index = source_index;
 123
 124         string name = module->source_map.get_name(index);
 125         if(name.empty())
 126                 name = format("<%d>", index);
 127         tokenizer.set_location(Location(name, line));
 128 }
 129
 130 string Parser::expect_type()
 131 {
 132         string token = tokenizer.parse_token();
 133         if(!is_type(token))
 134                 throw parse_error(tokenizer.get_location(), token, "a type");
 135         return token;
 136 }
 137
 138 string Parser::expect_identifier()
 139 {
 140         string token = tokenizer.parse_token();
 141         if(!is_identifier(token))
 142                 throw parse_error(tokenizer.get_location(), token, "an identifier");
 143         return token;
 144 }
 145
 146 int Parser::expect_integer()
 147 {
 148         string token = tokenizer.parse_token();
 149         if(!isnumrc(token))
 150                 throw parse_error(tokenizer.get_location(), token, "an integer literal");
 151         return lexical_cast<int>(token);
 152 }
 153
 154 bool Parser::check(const string &token)
 155 {
 156         bool result = (tokenizer.peek_token()==token);
 157         if(result)
 158                 tokenizer.parse_token();
 159         return result;
 160 }
 161
 162 bool Parser::is_interface_qualifier(const string &token)
 163 {
 164         return (token=="uniform" || token=="in" || token=="out");
 165 }
 166
 167 bool Parser::is_sampling_qualifier(const string &token)
 168 {
 169         return (token=="centroid" || token=="sample");
 170 }
 171
 172 bool Parser::is_interpolation_qualifier(const string &token)
 173 {
 174         return (token=="smooth" || token=="flat" || token=="noperspective");
 175 }
 176
 177 bool Parser::is_precision_qualifier(const string &token)
 178 {
 179         return (token=="highp" || token=="mediump" || token=="lowp");
 180 }
 181
 182 bool Parser::is_qualifier(const string &token)
 183 {
 184         return (token=="const" ||
 185                 is_interface_qualifier(token) ||
 186                 is_sampling_qualifier(token) ||
 187                 is_interpolation_qualifier(token) ||
 188                 is_precision_qualifier(token));
 189 }
 190
 191 bool Parser::is_type(const string &token)
 192 {
 193         return declared_types.count(token);
 194 }
 195
 196 bool Parser::is_identifier(const string &token)
 197 {
 198         static Regex re("^[a-zA-Z_][a-zA-Z0-9_]*$");
 199         return re.match(token);
 200 }
 201
 202 template<typename T>
 203 RefPtr<T> Parser::create_node()
 204 {
 205         RefPtr<T> node = new T;
 206         node->source = source_index;
 207         node->line = tokenizer.get_location().line;
 208         return node;
 209 }
 210
 211 template<typename T>
 212 RefPtr<T> Parser::parse_with_recovery(RefPtr<T> (Parser::*parse_func)())
 213 {
 214         tokenizer.clear_progress_mark();
 215         try
 216         {
 217                 return (this->*parse_func)();
 218         }
 219         catch(const invalid_shader_source &exc)
 220         {
 221                 errors.push_back(exc.what());
 222         }
 223
 224         if(tokenizer.get_last_token()!=";" || !tokenizer.get_progress_mark())
 225         {
 226                 unsigned scope_level = 0;
 227                 while(1)
 228                 {
 229                         if(tokenizer.peek_token()=="}" && scope_level==0)
 230                         {
 231                                 if(!tokenizer.get_progress_mark())
 232                                         tokenizer.parse_token();
 233                                 break;
 234                         }
 235
 236                         string token = tokenizer.parse_token();
 237                         if(token=="}")
 238                         {
 239                                 --scope_level;
 240                                 if(scope_level==0)
 241                                         break;
 242                         }
 243                         else if(token=="{")
 244                                 ++scope_level;
 245                         else if(token==";" && scope_level==0)
 246                                 break;
 247                         else if(token.empty())
 248                                 break;
 249                 }
 250         }
 251
 252         return RefPtr<T>();
 253 }
 254
 255 RefPtr<Statement> Parser::parse_global_declaration()
 256 {
 257         string token = tokenizer.peek_token();
 258         SetFlag disallow(allow_stage_change, false);
 259
 260         if(token=="import")
 261                 return parse_import();
 262         else if(token=="precision")
 263                 return parse_precision();
 264         else if(token=="layout")
 265         {
 266                 RefPtr<Layout> layout = parse_layout();
 267                 token = tokenizer.peek_token();
 268                 if(is_interface_qualifier(token) && tokenizer.peek_token(1)==";")
 269                 {
 270                         RefPtr<InterfaceLayout> iface_lo = create_node<InterfaceLayout>();
 271                         iface_lo->layout.qualifiers = layout->qualifiers;
 272                         iface_lo->interface = tokenizer.parse_token();
 273                         tokenizer.expect(";");
 274                         return iface_lo;
 275                 }
 276                 else
 277                 {
 278                         RefPtr<VariableDeclaration> var = parse_variable_declaration();
 279                         var->layout = layout;
 280                         return var;
 281                 }
 282         }
 283         else if(token=="typedef")
 284                 return parse_type_declaration();
 285         else if(token=="struct")
 286                 return parse_struct_declaration();
 287         else if(is_interface_qualifier(token))
 288         {
 289                 string next = tokenizer.peek_token(1);
 290                 if(is_type(next) || is_qualifier(next))
 291                         return parse_variable_declaration();
 292                 else
 293                         return parse_interface_block();
 294         }
 295         else if(is_qualifier(token))
 296                 return parse_variable_declaration();
 297         else if(token=="virtual")
 298                 return parse_function_declaration();
 299         else if(is_type(token))
 300         {
 301                 if(tokenizer.peek_token(2)=="(")
 302                         return parse_function_declaration();
 303                 else
 304                         return parse_variable_declaration();
 305         }
 306         else if(token.empty())
 307                 return 0;
 308         else
 309                 throw parse_error(tokenizer.get_location(), token, "a global declaration");
 310 }
 311
 312 RefPtr<Statement> Parser::parse_statement()
 313 {
 314         string token = tokenizer.peek_token();
 315         if(token=="if")
 316                 return parse_conditional();
 317         else if(token=="for")
 318                 return parse_for();
 319         else if(token=="while")
 320                 return parse_while();
 321         else if(token=="passthrough")
 322                 return parse_passthrough();
 323         else if(token=="return")
 324                 return parse_return();
 325         else if(token=="break" || token=="continue" || token=="discard")
 326         {
 327                 RefPtr<Jump> jump = create_node<Jump>();
 328                 jump->keyword = tokenizer.parse_token();
 329                 tokenizer.expect(";");
 330
 331                 return jump;
 332         }
 333         else if(is_qualifier(token) || is_type(token))
 334                 return parse_variable_declaration();
 335         else if(token==";")
 336         {
 337                 tokenizer.parse_token();
 338                 throw invalid_shader_source(tokenizer.get_location(), "Empty statement not allowed");
 339         }
 340         else if(!token.empty())
 341         {
 342                 RefPtr<ExpressionStatement> expr = create_node<ExpressionStatement>();
 343                 expr->expression = parse_expression();
 344                 tokenizer.expect(";");
 345
 346                 return expr;
 347         }
 348         else
 349                 throw parse_error(tokenizer.get_location(), token, "a statement");
 350 }
 351
 352 RefPtr<Import> Parser::parse_import()
 353 {
 354         if(cur_stage->type!=Stage::SHARED)
 355                 throw invalid_shader_source(tokenizer.get_location(), "Imports are only allowed in the shared section");
 356
 357         tokenizer.expect("import");
 358         RefPtr<Import> import = create_node<Import>();
 359         import->module = expect_identifier();
 360         tokenizer.expect(";");
 361         return import;
 362 }
 363
 364 RefPtr<Precision> Parser::parse_precision()
 365 {
 366         tokenizer.expect("precision");
 367         RefPtr<Precision> precision = create_node<Precision>();
 368
 369         precision->precision = tokenizer.parse_token();
 370         if(!is_precision_qualifier(precision->precision))
 371                 throw parse_error(tokenizer.get_location(), precision->precision, "a precision qualifier");
 372
 373         // TODO Add validation for this
 374         precision->type = expect_type();
 375
 376         tokenizer.expect(";");
 377
 378         return precision;
 379 }
 380
 381 RefPtr<Layout> Parser::parse_layout()
 382 {
 383         tokenizer.expect("layout");
 384         tokenizer.expect("(");
 385         RefPtr<Layout> layout = create_node<Layout>();
 386         while(1)
 387         {
 388                 string token = tokenizer.parse_token();
 389                 if(token==")")
 390                         throw parse_error(tokenizer.get_location(), token, "a layout qualifier name");
 391
 392                 layout->qualifiers.push_back(Layout::Qualifier());
 393                 Layout::Qualifier &qual = layout->qualifiers.back();
 394                 qual.name = token;
 395
 396                 if((qual.has_value = check("=")))
 397                 {
 398                         if(qual.name=="constant_id" && tokenizer.peek_token()=="auto")
 399                         {
 400                                 qual.value = -1;
 401                                 tokenizer.parse_token();
 402                         }
 403                         else
 404                                 qual.value = expect_integer();
 405                 }
 406
 407                 if(tokenizer.peek_token()==")")
 408                         break;
 409
 410                 tokenizer.expect(",");
 411         }
 412         tokenizer.expect(")");
 413
 414         return layout;
 415 }
 416
 417 template<typename T>
 418 void Parser::parse_block(Block &block, bool require_braces, RefPtr<T> (Parser::*parse_content)())
 419 {
 420         bool have_braces = (require_braces || tokenizer.peek_token()=="{");
 421         if(have_braces)
 422                 tokenizer.expect("{");
 423
 424         if(have_braces)
 425         {
 426                 while(tokenizer.peek_token()!="}")
 427                         if(RefPtr<Statement> node = parse_with_recovery(parse_content))
 428                                 block.body.push_back(node);
 429         }
 430         else
 431                 block.body.push_back((this->*parse_content)());
 432
 433         block.use_braces = (require_braces || block.body.size()!=1);
 434
 435         if(have_braces)
 436                 tokenizer.expect("}");
 437 }
 438
 439 RefPtr<Expression> Parser::parse_expression(const Operator *outer_oper)
 440 {
 441         unsigned outer_precedence = (outer_oper ? outer_oper->precedence+(outer_oper->assoc==Operator::RIGHT_TO_LEFT) : 20);
 442         RefPtr<Expression> left;
 443         VariableReference *left_var = 0;
 444         while(1)
 445         {
 446                 string token = tokenizer.peek_token();
 447
 448                 const Operator *oper = 0;
 449                 for(const Operator *i=Operator::operators; (!oper && i->type); ++i)
 450                         if(token==i->token && (!left || i->type!=Operator::PREFIX) && (left || i->type!=Operator::POSTFIX))
 451                                 oper = i;
 452
 453                 bool lower_precedence = (oper && oper->type!=Operator::PREFIX && oper->precedence>=outer_precedence);
 454                 if(token==";" || token==")" || token=="]" || token=="," || token==":" || lower_precedence)
 455                 {
 456                         if(left)
 457                                 return left;
 458                         else
 459                                 throw parse_error(tokenizer.get_location(), token, "an expression");
 460                 }
 461                 else if(left)
 462                 {
 463                         if(token=="(")
 464                         {
 465                                 if(!left_var)
 466                                         throw invalid_shader_source(tokenizer.get_location(), "Syntax error before '(': function name must be an identifier");
 467                                 left = parse_function_call(*left_var);
 468                         }
 469                         else if(token==".")
 470                         {
 471                                 RefPtr<MemberAccess> memacc = create_node<MemberAccess>();
 472                                 memacc->left = left;
 473                                 memacc->oper = oper;
 474                                 tokenizer.parse_token();
 475                                 memacc->member = expect_identifier();
 476                                 left = memacc;
 477                         }
 478                         else if(oper && oper->type==Operator::POSTFIX)
 479                         {
 480                                 RefPtr<UnaryExpression> unary = create_node<UnaryExpression>();
 481                                 unary->oper = oper;
 482                                 tokenizer.parse_token();
 483                                 unary->expression = left;
 484                                 left = unary;
 485                         }
 486                         else if(oper && oper->type==Operator::BINARY)
 487                                 left = parse_binary(left, *oper);
 488                         else if(oper && oper->type==Operator::TERNARY)
 489                                 left = parse_ternary(left, *oper);
 490                         else
 491                                 throw parse_error(tokenizer.get_location(), token, "an operator");
 492                         left_var = 0;
 493                 }
 494                 else
 495                 {
 496                         if(token=="(")
 497                         {
 498                                 tokenizer.parse_token();
 499                                 RefPtr<ParenthesizedExpression> parexpr = create_node<ParenthesizedExpression>();
 500                                 parexpr->expression = parse_expression();
 501                                 tokenizer.expect(")");
 502                                 left = parexpr;
 503                         }
 504                         else if(isdigit(token[0]) || token=="true" || token=="false")
 505                                 left = parse_literal();
 506                         else if(is_identifier(token))
 507                         {
 508                                 RefPtr<VariableReference> var = create_node<VariableReference>();
 509                                 var->name = expect_identifier();
 510                                 left = var;
 511                                 left_var = var.get();
 512                         }
 513                         else if(oper && oper->type==Operator::PREFIX)
 514                         {
 515                                 RefPtr<UnaryExpression> unary = create_node<UnaryExpression>();
 516                                 unary->oper = oper;
 517                                 tokenizer.parse_token();
 518                                 unary->expression = parse_expression(oper);
 519                                 left = unary;
 520                         }
 521                         else
 522                                 throw parse_error(tokenizer.get_location(), token, "an expression");
 523                 }
 524         }
 525 }
 526
 527 RefPtr<Literal> Parser::parse_literal()
 528 {
 529         RefPtr<Literal> literal = create_node<Literal>();
 530         literal->token = tokenizer.parse_token();
 531         if(isdigit(literal->token[0]))
 532         {
 533                 // TODO have the tokenizer return the type of the token
 534                 if(isnumrc(literal->token))
 535                         literal->value = lexical_cast<int>(literal->token);
 536                 else
 537                         literal->value = lexical_cast<float>(literal->token);
 538         }
 539         else if(literal->token=="true" || literal->token=="false")
 540                 literal->value = (literal->token=="true");
 541         else
 542                 throw parse_error(tokenizer.get_location(), literal->token, "a literal");
 543
 544         return literal;
 545 }
 546
 547 RefPtr<BinaryExpression> Parser::parse_binary(const RefPtr<Expression> &left, const Operator &oper)
 548 {
 549         RefPtr<BinaryExpression> binary = (oper.precedence==16 ?
 550                 static_cast<RefPtr<BinaryExpression> >(create_node<Assignment>()) : create_node<BinaryExpression>());
 551         binary->left = left;
 552         binary->oper = &oper;
 553         tokenizer.expect(oper.token);
 554         if(oper.token[0]=='[')
 555         {
 556                 binary->right = parse_expression();
 557                 tokenizer.expect("]");
 558         }
 559         else
 560                 binary->right = parse_expression(&oper);
 561         return binary;
 562 }
 563
 564 RefPtr<TernaryExpression> Parser::parse_ternary(const RefPtr<Expression> &cond, const Operator &oper)
 565 {
 566         RefPtr<TernaryExpression> ternary = create_node<TernaryExpression>();
 567         ternary->condition = cond;
 568         ternary->oper = &oper;
 569         tokenizer.expect("?");
 570         ternary->true_expr = parse_expression(&oper);
 571         tokenizer.expect(":");
 572         ternary->false_expr = parse_expression(&oper);
 573         return ternary;
 574 }
 575
 576 RefPtr<FunctionCall> Parser::parse_function_call(const VariableReference &var)
 577 {
 578         RefPtr<FunctionCall> call = create_node<FunctionCall>();
 579         call->name = var.name;
 580         call->constructor = is_type(call->name);
 581         call->oper = &Operator::get_operator("(", Operator::POSTFIX);
 582         tokenizer.expect("(");
 583         while(tokenizer.peek_token()!=")")
 584         {
 585                 if(!call->arguments.empty())
 586                         tokenizer.expect(",");
 587                 call->arguments.push_back(parse_expression());
 588         }
 589         tokenizer.expect(")");
 590         return call;
 591 }
 592
 593 RefPtr<TypeDeclaration> Parser::parse_type_declaration()
 594 {
 595         tokenizer.expect("typedef");
 596
 597         RefPtr<TypeDeclaration> type;
 598         if(tokenizer.peek_token()=="image")
 599                 type = parse_image_type_declaration();
 600         else
 601                 type = parse_basic_type_declaration();
 602
 603         tokenizer.expect(";");
 604         declared_types.insert(type->name);
 605         return type;
 606 }
 607
 608 RefPtr<BasicTypeDeclaration> Parser::parse_basic_type_declaration()
 609 {
 610         RefPtr<BasicTypeDeclaration> type = create_node<BasicTypeDeclaration>();
 611
 612         if(tokenizer.peek_token()=="vector")
 613         {
 614                 type->kind = BasicTypeDeclaration::VECTOR;
 615
 616                 tokenizer.parse_token();
 617                 tokenizer.expect("(");
 618                 type->size = expect_integer();
 619                 tokenizer.expect(")");
 620         }
 621
 622         type->base = expect_type();
 623         type->name = expect_identifier();
 624
 625         if(type->kind==BasicTypeDeclaration::ALIAS && check("["))
 626         {
 627                 type->kind = BasicTypeDeclaration::ARRAY;
 628                 tokenizer.expect("]");
 629         }
 630
 631         return type;
 632 }
 633
 634 RefPtr<ImageTypeDeclaration> Parser::parse_image_type_declaration()
 635 {
 636         tokenizer.expect("image");
 637         tokenizer.expect("(");
 638
 639         RefPtr<ImageTypeDeclaration> type = create_node<ImageTypeDeclaration>();
 640         while(1)
 641         {
 642                 string token = tokenizer.parse_token();
 643                 if(token=="dimensions")
 644                 {
 645                         tokenizer.expect("=");
 646                         token = tokenizer.parse_token();
 647                         if(token=="1")
 648                                 type->dimensions = ImageTypeDeclaration::ONE;
 649                         else if(token=="2")
 650                                 type->dimensions = ImageTypeDeclaration::TWO;
 651                         else if(token=="3")
 652                                 type->dimensions = ImageTypeDeclaration::THREE;
 653                         else if(token=="cube")
 654                                 type->dimensions = ImageTypeDeclaration::CUBE;
 655                         else
 656                                 throw parse_error(tokenizer.get_location(), token, "dimensions");
 657
 658                         if(check("["))
 659                         {
 660                                 type->array = true;
 661                                 tokenizer.expect("]");
 662                         }
 663                 }
 664                 else if(token=="sampled")
 665                         type->sampled = true;
 666                 else if(token=="shadow")
 667                         type->shadow = true;
 668                 else
 669                         throw parse_error(tokenizer.get_location(), token, "image type attribute");
 670
 671                 token = tokenizer.peek_token();
 672                 if(token==")")
 673                         break;
 674
 675                 tokenizer.expect(",");
 676         }
 677         tokenizer.expect(")");
 678
 679         type->base = expect_type();
 680         type->name = expect_identifier();
 681
 682         return type;
 683 }
 684
 685 RefPtr<StructDeclaration> Parser::parse_struct_declaration()
 686 {
 687         tokenizer.expect("struct");
 688         RefPtr<StructDeclaration> strct = create_node<StructDeclaration>();
 689
 690         strct->name = expect_identifier();
 691         parse_block(strct->members, true, &Parser::parse_variable_declaration);
 692         tokenizer.expect(";");
 693
 694         declared_types.insert(strct->name);
 695         return strct;
 696 }
 697
 698 RefPtr<VariableDeclaration> Parser::parse_variable_declaration()
 699 {
 700         RefPtr<VariableDeclaration> var = create_node<VariableDeclaration>();
 701
 702         string token = tokenizer.peek_token();
 703         while(is_qualifier(token))
 704         {
 705                 tokenizer.parse_token();
 706                 if(is_interface_qualifier(token))
 707                         var->interface = token;
 708                 else if(is_sampling_qualifier(token))
 709                         var->sampling = token;
 710                 else if(is_interpolation_qualifier(token))
 711                         var->interpolation = token;
 712                 else if(is_precision_qualifier(token))
 713                         var->precision = token;
 714                 else if(token=="const")
 715                         var->constant = true;
 716                 token = tokenizer.peek_token();
 717         }
 718
 719         var->type = expect_type();
 720         var->name = expect_identifier();
 721
 722         if(check("["))
 723         {
 724                 var->array = true;
 725                 if(!check("]"))
 726                 {
 727                         var->array_size = parse_expression();
 728                         tokenizer.expect("]");
 729                 }
 730         }
 731
 732         if(check("="))
 733                 var->init_expression = parse_expression();
 734
 735         tokenizer.expect(";");
 736         return var;
 737 }
 738
 739 RefPtr<VariableDeclaration> Parser::parse_variable_declaration_with_layout()
 740 {
 741         RefPtr<Layout> layout;
 742         if(tokenizer.peek_token()=="layout")
 743                 layout = parse_layout();
 744
 745         RefPtr<VariableDeclaration> var = parse_variable_declaration();
 746         var->layout = layout;
 747
 748         return var;
 749 }
 750
 751 RefPtr<FunctionDeclaration> Parser::parse_function_declaration()
 752 {
 753         RefPtr<FunctionDeclaration> func = create_node<FunctionDeclaration>();
 754
 755         func->virtua = check("virtual");
 756         func->return_type = expect_type();
 757         func->name = expect_identifier();
 758         tokenizer.expect("(");
 759         while(tokenizer.peek_token()!=")")
 760         {
 761                 if(!func->parameters.empty())
 762                         tokenizer.expect(",");
 763
 764                 RefPtr<VariableDeclaration> var = create_node<VariableDeclaration>();
 765                 string token = tokenizer.peek_token();
 766                 if(token=="in" || token=="out" || token=="inout")
 767                         var->interface = tokenizer.parse_token();
 768                 var->type = expect_type();
 769                 var->name = expect_identifier();
 770                 func->parameters.push_back(var);
 771         }
 772         tokenizer.expect(")");
 773
 774         func->overrd = check("override");
 775
 776         string token = tokenizer.peek_token();
 777         if(token=="{")
 778         {
 779                 func->definition = func.get();
 780                 parse_block(func->body, true, &Parser::parse_statement);
 781         }
 782         else if(token==";")
 783                 tokenizer.parse_token();
 784         else
 785                 throw parse_error(tokenizer.get_location(), token, "'{' or ';'");
 786
 787         return func;
 788 }
 789
 790 RefPtr<InterfaceBlock> Parser::parse_interface_block()
 791 {
 792         RefPtr<InterfaceBlock> iface = create_node<InterfaceBlock>();
 793
 794         iface->interface = tokenizer.parse_token();
 795         if(!is_interface_qualifier(iface->interface))
 796                 throw parse_error(tokenizer.get_location(), iface->interface, "an interface qualifier");
 797
 798         iface->name = expect_identifier();
 799         iface->members = new Block;
 800         parse_block(*iface->members, true, &Parser::parse_variable_declaration_with_layout);
 801         if(!check(";"))
 802         {
 803                 iface->instance_name = expect_identifier();
 804                 if(check("["))
 805                 {
 806                         iface->array = true;
 807                         tokenizer.expect("]");
 808                 }
 809                 tokenizer.expect(";");
 810         }
 811
 812         return iface;
 813 }
 814
 815 RefPtr<Conditional> Parser::parse_conditional()
 816 {
 817         tokenizer.expect("if");
 818         RefPtr<Conditional> cond = create_node<Conditional>();
 819         tokenizer.expect("(");
 820         cond->condition = parse_expression();
 821         tokenizer.expect(")");
 822
 823         parse_block(cond->body, false, &Parser::parse_statement);
 824
 825         string token = tokenizer.peek_token();
 826         if(token=="else")
 827         {
 828                 tokenizer.parse_token();
 829                 parse_block(cond->else_body, false, &Parser::parse_statement);
 830         }
 831
 832         return cond;
 833 }
 834
 835 RefPtr<Iteration> Parser::parse_for()
 836 {
 837         tokenizer.expect("for");
 838         RefPtr<Iteration> loop = create_node<Iteration>();
 839         tokenizer.expect("(");
 840         string token = tokenizer.peek_token();
 841         if(is_type(token))
 842                 loop->init_statement = parse_statement();
 843         else
 844         {
 845                 if(token!=";")
 846                 {
 847                         RefPtr<ExpressionStatement> expr = create_node<ExpressionStatement>();
 848                         expr->expression = parse_expression();
 849                         loop->init_statement = expr;
 850                 }
 851                 tokenizer.expect(";");
 852         }
 853         if(tokenizer.peek_token()!=";")
 854                 loop->condition = parse_expression();
 855         tokenizer.expect(";");
 856         if(tokenizer.peek_token()!=")")
 857                 loop->loop_expression = parse_expression();
 858         tokenizer.expect(")");
 859
 860         parse_block(loop->body, false, &Parser::parse_statement);
 861
 862         return loop;
 863 }
 864
 865 RefPtr<Iteration> Parser::parse_while()
 866 {
 867         tokenizer.expect("while");
 868         RefPtr<Iteration> loop = create_node<Iteration>();
 869         tokenizer.expect("(");
 870         loop->condition = parse_expression();
 871         tokenizer.expect(")");
 872
 873         parse_block(loop->body, false, &Parser::parse_statement);
 874
 875         return loop;
 876 }
 877
 878 RefPtr<Passthrough> Parser::parse_passthrough()
 879 {
 880         tokenizer.expect("passthrough");
 881         RefPtr<Passthrough> pass = create_node<Passthrough>();
 882         if(cur_stage->type==Stage::GEOMETRY)
 883         {
 884                 tokenizer.expect("[");
 885                 pass->subscript = parse_expression();
 886                 tokenizer.expect("]");
 887         }
 888         tokenizer.expect(";");
 889         return pass;
 890 }
 891
 892 RefPtr<Return> Parser::parse_return()
 893 {
 894         tokenizer.expect("return");
 895         RefPtr<Return> ret = create_node<Return>();
 896         if(tokenizer.peek_token()!=";")
 897                 ret->expression = parse_expression();
 898         tokenizer.expect(";");
 899         return ret;
 900 }
 901
 902 } // namespace SL
 903 } // namespace GL
 904 } // namespace Msp