source/glsl/parser.cpp

   1 #include <msp/core/algorithm.h>
   2 #include <msp/core/raii.h>
   3 #include <msp/strings/format.h>
   4 #include <msp/strings/regex.h>
   5 #include <msp/strings/utils.h>
   6 #include "builtin.h"
   7 #include "glsl_error.h"
   8 #include "modulecache.h"
   9 #include "parser.h"
  10
  11 #undef interface
  12
  13 using namespace std;
  14
  15 namespace Msp {
  16 namespace GL {
  17 namespace SL {
  18
  19 Parser::Parser(ModuleCache *s):
  20         mod_cache(s),
  21         preprocessor(tokenizer),
  22         module(0)
  23 {
  24         tokenizer.signal_preprocess.connect(sigc::mem_fun(&preprocessor, &Preprocessor::preprocess));
  25         preprocessor.signal_version.connect(sigc::mem_fun(this, &Parser::set_required_version));
  26         preprocessor.signal_source.connect(sigc::mem_fun(this, &Parser::source_reference));
  27         preprocessor.signal_stage_change.connect(sigc::mem_fun(this, &Parser::stage_change));
  28         preprocessor.signal_line.connect(sigc::mem_fun(this, &Parser::line_change));
  29 }
  30
  31 void Parser::parse(Module &m, const string &s, const string &n, int i)
  32 {
  33         SetForScope<Module *> set_module(module, &m);
  34         source = s;
  35         parse_source(n, i);
  36 }
  37
  38 void Parser::parse(Module &m, IO::Base &io, const string &n, int i)
  39 {
  40         SetForScope<Module *> set_module(module, &m);
  41         source = string();
  42         while(!io.eof())
  43         {
  44                 char buffer[4096];
  45                 unsigned len = io.read(buffer, sizeof(buffer));
  46                 source.append(buffer, len);
  47         }
  48         parse_source(n, i);
  49 }
  50
  51 void Parser::parse_source(const string &name, int index)
  52 {
  53         cur_stage = &module->shared;
  54         base_index = index;
  55         source_index = index;
  56         if(index>=0)
  57                 source_reference(1, name);
  58
  59         if(const Stage *builtin = get_builtins(Stage::SHARED))
  60         {
  61                 for(const auto &kvp: builtin->types)
  62                         global_types.insert(kvp.first);
  63         }
  64
  65         tokenizer.begin(source, name);
  66         allow_stage_change = true;
  67         while(!tokenizer.peek_token().empty())
  68                 if(RefPtr<Statement> statement = parse_with_recovery(&Parser::parse_global_declaration))
  69                         cur_stage->content.body.push_back(statement);
  70
  71         if(!errors.empty())
  72                 throw invalid_shader_source(join(errors.begin(), errors.end(), "\n"));
  73 }
  74
  75 void Parser::set_required_version(const Version &ver)
  76 {
  77         cur_stage->required_features.glsl_version = ver;
  78 }
  79
  80 void Parser::source_reference(unsigned index, const string &name)
  81 {
  82         if(index<1 || base_index<0)
  83                 throw invalid_shader_source(tokenizer.get_location(), "Invalid source reference");
  84
  85         module->source_map.set_name(base_index+index-1, name);
  86 }
  87
  88 void Parser::stage_change(Stage::Type stage)
  89 {
  90         if(!allow_stage_change)
  91                 throw invalid_shader_source(tokenizer.get_location(), "Changing stage not allowed here");
  92         else if(stage<=cur_stage->type)
  93                 throw invalid_shader_source(tokenizer.get_location(), "Stage '%s' not allowed here", Stage::get_stage_name(stage));
  94
  95         module->stages.push_back(stage);
  96
  97         if(cur_stage->type!=Stage::SHARED)
  98                 module->stages.back().previous = cur_stage;
  99         cur_stage = &module->stages.back();
 100
 101         stage_types.clear();
 102         for(const Module *m: imported_modules)
 103         {
 104                 auto j = find_member(m->stages, stage, &Stage::type);
 105                 if(j!=m->stages.end())
 106                 {
 107                         for(const auto &kvp: j->types)
 108                                 stage_types.insert(kvp.first);
 109                 }
 110         }
 111 }
 112
 113 void Parser::line_change(int index, unsigned line)
 114 {
 115         if(index>0)
 116                 source_index = base_index+index-1;
 117         else if(index==0)
 118                 source_index = 0;
 119         else
 120                 index = source_index;
 121
 122         string name = module->source_map.get_name(index);
 123         if(name.empty())
 124                 name = format("<%d>", index);
 125         tokenizer.set_location(Location(name, line));
 126 }
 127
 128 string Parser::expect_type()
 129 {
 130         string token = tokenizer.parse_token();
 131         if(!is_type(token))
 132                 throw parse_error(tokenizer.get_location(), token, "a type");
 133         return token;
 134 }
 135
 136 string Parser::expect_identifier()
 137 {
 138         string token = tokenizer.parse_token();
 139         if(!is_identifier(token))
 140                 throw parse_error(tokenizer.get_location(), token, "an identifier");
 141         return token;
 142 }
 143
 144 int Parser::expect_integer()
 145 {
 146         string token = tokenizer.parse_token();
 147         if(!isnumrc(token))
 148                 throw parse_error(tokenizer.get_location(), token, "an integer literal");
 149         return lexical_cast<int>(token);
 150 }
 151
 152 bool Parser::check(const string &token)
 153 {
 154         bool result = (tokenizer.peek_token()==token);
 155         if(result)
 156                 tokenizer.parse_token();
 157         return result;
 158 }
 159
 160 bool Parser::is_interface_qualifier(const string &token)
 161 {
 162         return (token=="uniform" || token=="in" || token=="out");
 163 }
 164
 165 bool Parser::is_sampling_qualifier(const string &token)
 166 {
 167         return (token=="centroid" || token=="sample");
 168 }
 169
 170 bool Parser::is_interpolation_qualifier(const string &token)
 171 {
 172         return (token=="smooth" || token=="flat" || token=="noperspective");
 173 }
 174
 175 bool Parser::is_precision_qualifier(const string &token)
 176 {
 177         return (token=="highp" || token=="mediump" || token=="lowp");
 178 }
 179
 180 bool Parser::is_qualifier(const string &token)
 181 {
 182         return (token=="const" ||
 183                 is_interface_qualifier(token) ||
 184                 is_sampling_qualifier(token) ||
 185                 is_interpolation_qualifier(token) ||
 186                 is_precision_qualifier(token));
 187 }
 188
 189 bool Parser::is_type(const string &token)
 190 {
 191         return global_types.count(token) || stage_types.count(token);
 192 }
 193
 194 bool Parser::is_identifier(const string &token)
 195 {
 196         static Regex re("^[a-zA-Z_][a-zA-Z0-9_]*$");
 197         return static_cast<bool>(re.match(token));
 198 }
 199
 200 template<typename T>
 201 RefPtr<T> Parser::create_node()
 202 {
 203         RefPtr<T> node = new T;
 204         node->source = source_index;
 205         node->line = tokenizer.get_location().line;
 206         return node;
 207 }
 208
 209 template<typename T>
 210 RefPtr<T> Parser::parse_with_recovery(RefPtr<T> (Parser::*parse_func)())
 211 {
 212         tokenizer.clear_progress_mark();
 213         try
 214         {
 215                 return (this->*parse_func)();
 216         }
 217         catch(const invalid_shader_source &exc)
 218         {
 219                 errors.push_back(exc.what());
 220         }
 221
 222         if(tokenizer.get_last_token()!=";" || !tokenizer.get_progress_mark())
 223         {
 224                 unsigned scope_level = 0;
 225                 while(1)
 226                 {
 227                         if(tokenizer.peek_token()=="}" && scope_level==0)
 228                         {
 229                                 if(!tokenizer.get_progress_mark())
 230                                         tokenizer.parse_token();
 231                                 break;
 232                         }
 233
 234                         string token = tokenizer.parse_token();
 235                         if(token=="}")
 236                         {
 237                                 --scope_level;
 238                                 if(scope_level==0)
 239                                         break;
 240                         }
 241                         else if(token=="{")
 242                                 ++scope_level;
 243                         else if(token==";" && scope_level==0)
 244                                 break;
 245                         else if(token.empty())
 246                                 break;
 247                 }
 248         }
 249
 250         return RefPtr<T>();
 251 }
 252
 253 RefPtr<Statement> Parser::parse_global_declaration()
 254 {
 255         string token = tokenizer.peek_token();
 256         SetFlag disallow(allow_stage_change, false);
 257
 258         if(token=="import")
 259                 return parse_import();
 260         else if(token=="precision")
 261                 return parse_precision();
 262         else if(token=="layout")
 263         {
 264                 RefPtr<Layout> layout = parse_layout();
 265                 token = tokenizer.peek_token();
 266                 if(is_interface_qualifier(token) && tokenizer.peek_token(1)==";")
 267                 {
 268                         RefPtr<InterfaceLayout> iface_lo = create_node<InterfaceLayout>();
 269                         iface_lo->layout.source = layout->source;
 270                         iface_lo->layout.line = layout->line;
 271                         iface_lo->layout.qualifiers = layout->qualifiers;
 272                         iface_lo->interface = tokenizer.parse_token();
 273                         tokenizer.expect(";");
 274                         return iface_lo;
 275                 }
 276                 else if(is_interface_qualifier(token) && tokenizer.peek_token(2)=="{")
 277                 {
 278                         RefPtr<InterfaceBlock> iface = parse_interface_block();
 279                         iface->layout = layout;
 280                         return iface;
 281                 }
 282                 else
 283                 {
 284                         RefPtr<VariableDeclaration> var = parse_variable_declaration();
 285                         var->layout = layout;
 286                         return var;
 287                 }
 288         }
 289         else if(token=="typedef")
 290                 return parse_type_declaration();
 291         else if(token=="struct")
 292                 return parse_struct_declaration();
 293         else if(is_interface_qualifier(token))
 294         {
 295                 string next = tokenizer.peek_token(1);
 296                 if(is_type(next) || is_qualifier(next))
 297                         return parse_variable_declaration();
 298                 else
 299                         return parse_interface_block();
 300         }
 301         else if(is_qualifier(token))
 302                 return parse_variable_declaration();
 303         else if(token=="virtual")
 304                 return parse_function_declaration();
 305         else if(is_type(token))
 306         {
 307                 if(tokenizer.peek_token(2)=="(")
 308                         return parse_function_declaration();
 309                 else
 310                         return parse_variable_declaration();
 311         }
 312         else if(token.empty())
 313                 return 0;
 314         else
 315                 throw parse_error(tokenizer.get_location(), token, "a global declaration");
 316 }
 317
 318 RefPtr<Statement> Parser::parse_statement()
 319 {
 320         string token = tokenizer.peek_token();
 321         if(token=="if")
 322                 return parse_conditional();
 323         else if(token=="for")
 324                 return parse_for();
 325         else if(token=="while")
 326                 return parse_while();
 327         else if(token=="passthrough")
 328                 return parse_passthrough();
 329         else if(token=="return")
 330                 return parse_return();
 331         else if(token=="break" || token=="continue" || token=="discard")
 332         {
 333                 RefPtr<Jump> jump = create_node<Jump>();
 334                 jump->keyword = tokenizer.parse_token();
 335                 tokenizer.expect(";");
 336
 337                 return jump;
 338         }
 339         else if(is_qualifier(token) || is_type(token))
 340                 return parse_variable_declaration();
 341         else if(token==";")
 342         {
 343                 tokenizer.parse_token();
 344                 throw invalid_shader_source(tokenizer.get_location(), "Empty statement not allowed");
 345         }
 346         else if(!token.empty())
 347         {
 348                 RefPtr<ExpressionStatement> expr = create_node<ExpressionStatement>();
 349                 expr->expression = parse_expression();
 350                 tokenizer.expect(";");
 351
 352                 return expr;
 353         }
 354         else
 355                 throw parse_error(tokenizer.get_location(), token, "a statement");
 356 }
 357
 358 RefPtr<Import> Parser::parse_import()
 359 {
 360         if(cur_stage->type!=Stage::SHARED)
 361                 throw invalid_shader_source(tokenizer.get_location(), "Imports are only allowed in the shared section");
 362
 363         tokenizer.expect("import");
 364         RefPtr<Import> import = create_node<Import>();
 365         import->module = expect_identifier();
 366         tokenizer.expect(";");
 367
 368         if(mod_cache)
 369         {
 370                 const Module &imported_mod = mod_cache->get_module(import->module);
 371                 imported_modules.push_back(&imported_mod);
 372                 for(const auto &kvp: imported_mod.shared.types)
 373                         global_types.insert(kvp.first);
 374         }
 375
 376         return import;
 377 }
 378
 379 RefPtr<Precision> Parser::parse_precision()
 380 {
 381         tokenizer.expect("precision");
 382         RefPtr<Precision> precision = create_node<Precision>();
 383
 384         precision->precision = tokenizer.parse_token();
 385         if(!is_precision_qualifier(precision->precision))
 386                 throw parse_error(tokenizer.get_location(), precision->precision, "a precision qualifier");
 387
 388         // TODO Add validation for this
 389         precision->type = expect_type();
 390
 391         tokenizer.expect(";");
 392
 393         return precision;
 394 }
 395
 396 RefPtr<Layout> Parser::parse_layout()
 397 {
 398         tokenizer.expect("layout");
 399         tokenizer.expect("(");
 400         RefPtr<Layout> layout = create_node<Layout>();
 401         while(1)
 402         {
 403                 string token = tokenizer.parse_token();
 404                 if(token==")")
 405                         throw parse_error(tokenizer.get_location(), token, "a layout qualifier name");
 406
 407                 layout->qualifiers.push_back(token);
 408                 Layout::Qualifier &qual = layout->qualifiers.back();
 409
 410                 if((qual.has_value = check("=")))
 411                 {
 412                         if(qual.name=="constant_id" && tokenizer.peek_token()=="auto")
 413                         {
 414                                 qual.value = -1;
 415                                 tokenizer.parse_token();
 416                         }
 417                         else
 418                                 qual.value = expect_integer();
 419                 }
 420
 421                 if(tokenizer.peek_token()==")")
 422                         break;
 423
 424                 tokenizer.expect(",");
 425         }
 426         tokenizer.expect(")");
 427
 428         return layout;
 429 }
 430
 431 template<typename T>
 432 void Parser::parse_block(Block &block, bool require_braces, RefPtr<T> (Parser::*parse_content)())
 433 {
 434         bool have_braces = (require_braces || tokenizer.peek_token()=="{");
 435         if(have_braces)
 436                 tokenizer.expect("{");
 437
 438         if(have_braces)
 439         {
 440                 while(tokenizer.peek_token()!="}")
 441                         if(RefPtr<Statement> node = parse_with_recovery(parse_content))
 442                                 block.body.push_back(node);
 443         }
 444         else
 445                 block.body.push_back((this->*parse_content)());
 446
 447         block.use_braces = (require_braces || block.body.size()!=1);
 448
 449         if(have_braces)
 450                 tokenizer.expect("}");
 451 }
 452
 453 RefPtr<Expression> Parser::parse_expression(const Operator *outer_oper)
 454 {
 455         unsigned outer_precedence = (outer_oper ? outer_oper->precedence+(outer_oper->assoc==Operator::RIGHT_TO_LEFT) : 20);
 456         RefPtr<Expression> left;
 457         VariableReference *left_var = 0;
 458         while(1)
 459         {
 460                 string token = tokenizer.peek_token();
 461
 462                 const Operator *oper = 0;
 463                 for(const Operator *i=Operator::operators; (!oper && i->type); ++i)
 464                         if(token==i->token && (!left || i->type!=Operator::PREFIX) && (left || i->type!=Operator::POSTFIX))
 465                                 oper = i;
 466
 467                 bool lower_precedence = (oper && oper->type!=Operator::PREFIX && oper->precedence>=outer_precedence);
 468                 if(token==";" || token==")" || token=="]" || token=="," || token==":" || lower_precedence)
 469                 {
 470                         if(left)
 471                                 return left;
 472                         else
 473                                 throw parse_error(tokenizer.get_location(), token, "an expression");
 474                 }
 475                 else if(left)
 476                 {
 477                         if(token=="(")
 478                         {
 479                                 if(!left_var)
 480                                         throw invalid_shader_source(tokenizer.get_location(), "Syntax error before '(': function name must be an identifier");
 481                                 left = parse_function_call(*left_var);
 482                         }
 483                         else if(token==".")
 484                         {
 485                                 RefPtr<MemberAccess> memacc = create_node<MemberAccess>();
 486                                 memacc->left = left;
 487                                 memacc->oper = oper;
 488                                 tokenizer.parse_token();
 489                                 memacc->member = expect_identifier();
 490                                 left = memacc;
 491                         }
 492                         else if(oper && oper->type==Operator::POSTFIX)
 493                         {
 494                                 RefPtr<UnaryExpression> unary = create_node<UnaryExpression>();
 495                                 unary->oper = oper;
 496                                 tokenizer.parse_token();
 497                                 unary->expression = left;
 498                                 left = unary;
 499                         }
 500                         else if(oper && oper->type==Operator::BINARY)
 501                                 left = parse_binary(left, *oper);
 502                         else if(oper && oper->type==Operator::TERNARY)
 503                                 left = parse_ternary(left, *oper);
 504                         else
 505                                 throw parse_error(tokenizer.get_location(), token, "an operator");
 506                         left_var = 0;
 507                 }
 508                 else
 509                 {
 510                         if(token=="(")
 511                         {
 512                                 tokenizer.parse_token();
 513                                 left = parse_expression();
 514                                 tokenizer.expect(")");
 515                         }
 516                         else if(isdigit(token[0]) || token=="true" || token=="false")
 517                                 left = parse_literal();
 518                         else if(is_identifier(token))
 519                         {
 520                                 RefPtr<VariableReference> var = create_node<VariableReference>();
 521                                 var->name = expect_identifier();
 522                                 left = var;
 523                                 left_var = var.get();
 524                         }
 525                         else if(oper && oper->type==Operator::PREFIX)
 526                         {
 527                                 RefPtr<UnaryExpression> unary = create_node<UnaryExpression>();
 528                                 unary->oper = oper;
 529                                 tokenizer.parse_token();
 530                                 unary->expression = parse_expression(oper);
 531                                 left = unary;
 532                         }
 533                         else
 534                                 throw parse_error(tokenizer.get_location(), token, "an expression");
 535                 }
 536         }
 537 }
 538
 539 RefPtr<Literal> Parser::parse_literal()
 540 {
 541         RefPtr<Literal> literal = create_node<Literal>();
 542         literal->token = tokenizer.parse_token();
 543         if(isdigit(literal->token[0]))
 544         {
 545                 // TODO have the tokenizer return the type of the token
 546                 if(literal->token.back()=='u')
 547                         literal->value = lexical_cast<unsigned>(literal->token.substr(0, literal->token.size()-1));
 548                 else if(literal->token.back()=='f')
 549                         literal->value = lexical_cast<float>(literal->token.substr(0, literal->token.size()-1));
 550                 else if(literal->token.find('.')!=string::npos)
 551                         literal->value = lexical_cast<float>(literal->token);
 552                 else
 553                         literal->value = lexical_cast<int>(literal->token);
 554         }
 555         else if(literal->token=="true" || literal->token=="false")
 556                 literal->value = (literal->token=="true");
 557         else
 558                 throw parse_error(tokenizer.get_location(), literal->token, "a literal");
 559
 560         return literal;
 561 }
 562
 563 RefPtr<BinaryExpression> Parser::parse_binary(const RefPtr<Expression> &left, const Operator &oper)
 564 {
 565         RefPtr<BinaryExpression> binary = (oper.precedence==16 ?
 566                 static_cast<RefPtr<BinaryExpression> >(create_node<Assignment>()) : create_node<BinaryExpression>());
 567         binary->left = left;
 568         binary->oper = &oper;
 569         tokenizer.expect(oper.token);
 570         if(oper.token2[0])
 571         {
 572                 binary->right = parse_expression();
 573                 tokenizer.expect(oper.token2);
 574         }
 575         else
 576                 binary->right = parse_expression(&oper);
 577         return binary;
 578 }
 579
 580 RefPtr<TernaryExpression> Parser::parse_ternary(const RefPtr<Expression> &cond, const Operator &oper)
 581 {
 582         RefPtr<TernaryExpression> ternary = create_node<TernaryExpression>();
 583         ternary->condition = cond;
 584         ternary->oper = &oper;
 585         tokenizer.expect("?");
 586         ternary->true_expr = parse_expression(&oper);
 587         tokenizer.expect(":");
 588         ternary->false_expr = parse_expression(&oper);
 589         return ternary;
 590 }
 591
 592 RefPtr<FunctionCall> Parser::parse_function_call(const VariableReference &var)
 593 {
 594         RefPtr<FunctionCall> call = create_node<FunctionCall>();
 595         call->name = var.name;
 596         call->oper = &Operator::get_operator("(", Operator::POSTFIX);
 597         tokenizer.expect("(");
 598         while(tokenizer.peek_token()!=")")
 599         {
 600                 if(!call->arguments.empty())
 601                         tokenizer.expect(",");
 602                 call->arguments.push_back(parse_expression());
 603         }
 604         tokenizer.expect(")");
 605         return call;
 606 }
 607
 608 void Parser::add_type(TypeDeclaration &type)
 609 {
 610         cur_stage->types[type.name] = &type;
 611         if(cur_stage->type==Stage::SHARED)
 612                 global_types.insert(type.name);
 613         else
 614                 stage_types.insert(type.name);
 615 }
 616
 617 RefPtr<TypeDeclaration> Parser::parse_type_declaration()
 618 {
 619         tokenizer.expect("typedef");
 620
 621         RefPtr<TypeDeclaration> type;
 622         if(tokenizer.peek_token()=="image")
 623                 type = parse_image_type_declaration();
 624         else
 625                 type = parse_basic_type_declaration();
 626
 627         tokenizer.expect(";");
 628         add_type(*type);
 629         return type;
 630 }
 631
 632 RefPtr<BasicTypeDeclaration> Parser::parse_basic_type_declaration()
 633 {
 634         RefPtr<BasicTypeDeclaration> type = create_node<BasicTypeDeclaration>();
 635
 636         if(tokenizer.peek_token()=="vector")
 637         {
 638                 type->kind = BasicTypeDeclaration::VECTOR;
 639
 640                 tokenizer.parse_token();
 641                 tokenizer.expect("(");
 642                 type->size = expect_integer();
 643                 tokenizer.expect(")");
 644         }
 645
 646         type->base = expect_type();
 647         type->name = expect_identifier();
 648
 649         if(type->kind==BasicTypeDeclaration::ALIAS && check("["))
 650         {
 651                 type->kind = BasicTypeDeclaration::ARRAY;
 652                 tokenizer.expect("]");
 653         }
 654
 655         return type;
 656 }
 657
 658 RefPtr<ImageTypeDeclaration> Parser::parse_image_type_declaration()
 659 {
 660         tokenizer.expect("image");
 661         tokenizer.expect("(");
 662
 663         RefPtr<ImageTypeDeclaration> type = create_node<ImageTypeDeclaration>();
 664         while(1)
 665         {
 666                 string token = tokenizer.parse_token();
 667                 if(token=="dimensions")
 668                 {
 669                         tokenizer.expect("=");
 670                         token = tokenizer.parse_token();
 671                         if(token=="1")
 672                                 type->dimensions = ImageTypeDeclaration::ONE;
 673                         else if(token=="2")
 674                                 type->dimensions = ImageTypeDeclaration::TWO;
 675                         else if(token=="3")
 676                                 type->dimensions = ImageTypeDeclaration::THREE;
 677                         else if(token=="cube")
 678                                 type->dimensions = ImageTypeDeclaration::CUBE;
 679                         else
 680                                 throw parse_error(tokenizer.get_location(), token, "dimensions");
 681
 682                         if(check("["))
 683                         {
 684                                 type->array = true;
 685                                 tokenizer.expect("]");
 686                         }
 687                 }
 688                 else if(token=="sampled")
 689                         type->sampled = true;
 690                 else if(token=="shadow")
 691                         type->shadow = true;
 692                 else
 693                         throw parse_error(tokenizer.get_location(), token, "image type attribute");
 694
 695                 token = tokenizer.peek_token();
 696                 if(token==")")
 697                         break;
 698
 699                 tokenizer.expect(",");
 700         }
 701         tokenizer.expect(")");
 702
 703         type->base = expect_type();
 704         type->name = expect_identifier();
 705
 706         return type;
 707 }
 708
 709 RefPtr<StructDeclaration> Parser::parse_struct_declaration()
 710 {
 711         tokenizer.expect("struct");
 712         RefPtr<StructDeclaration> strct = create_node<StructDeclaration>();
 713
 714         strct->name = expect_identifier();
 715         parse_block(strct->members, true, &Parser::parse_variable_declaration);
 716         tokenizer.expect(";");
 717
 718         add_type(*strct);
 719         return strct;
 720 }
 721
 722 RefPtr<VariableDeclaration> Parser::parse_variable_declaration()
 723 {
 724         RefPtr<VariableDeclaration> var = create_node<VariableDeclaration>();
 725
 726         string token = tokenizer.peek_token();
 727         while(is_qualifier(token))
 728         {
 729                 tokenizer.parse_token();
 730                 if(is_interface_qualifier(token))
 731                         var->interface = token;
 732                 else if(is_sampling_qualifier(token))
 733                         var->sampling = token;
 734                 else if(is_interpolation_qualifier(token))
 735                         var->interpolation = token;
 736                 else if(is_precision_qualifier(token))
 737                         var->precision = token;
 738                 else if(token=="const")
 739                         var->constant = true;
 740                 token = tokenizer.peek_token();
 741         }
 742
 743         var->type = expect_type();
 744         var->name = expect_identifier();
 745
 746         if(check("["))
 747         {
 748                 var->array = true;
 749                 if(!check("]"))
 750                 {
 751                         var->array_size = parse_expression();
 752                         tokenizer.expect("]");
 753                 }
 754         }
 755
 756         if(check("="))
 757                 var->init_expression = parse_expression();
 758
 759         tokenizer.expect(";");
 760         return var;
 761 }
 762
 763 RefPtr<VariableDeclaration> Parser::parse_variable_declaration_with_layout()
 764 {
 765         RefPtr<Layout> layout;
 766         if(tokenizer.peek_token()=="layout")
 767                 layout = parse_layout();
 768
 769         RefPtr<VariableDeclaration> var = parse_variable_declaration();
 770         var->layout = layout;
 771
 772         return var;
 773 }
 774
 775 RefPtr<FunctionDeclaration> Parser::parse_function_declaration()
 776 {
 777         RefPtr<FunctionDeclaration> func = create_node<FunctionDeclaration>();
 778
 779         func->virtua = check("virtual");
 780         func->return_type = expect_type();
 781         func->name = expect_identifier();
 782         tokenizer.expect("(");
 783         while(tokenizer.peek_token()!=")")
 784         {
 785                 if(!func->parameters.empty())
 786                         tokenizer.expect(",");
 787
 788                 RefPtr<VariableDeclaration> var = create_node<VariableDeclaration>();
 789                 string token = tokenizer.peek_token();
 790                 if(token=="in" || token=="out" || token=="inout")
 791                         var->interface = tokenizer.parse_token();
 792                 var->type = expect_type();
 793                 var->name = expect_identifier();
 794                 func->parameters.push_back(var);
 795         }
 796         tokenizer.expect(")");
 797
 798         func->overrd = check("override");
 799
 800         string token = tokenizer.peek_token();
 801         if(token=="{")
 802         {
 803                 func->definition = func.get();
 804                 parse_block(func->body, true, &Parser::parse_statement);
 805         }
 806         else if(token==";")
 807                 tokenizer.parse_token();
 808         else
 809                 throw parse_error(tokenizer.get_location(), token, "'{' or ';'");
 810
 811         return func;
 812 }
 813
 814 RefPtr<InterfaceBlock> Parser::parse_interface_block()
 815 {
 816         RefPtr<InterfaceBlock> iface = create_node<InterfaceBlock>();
 817
 818         iface->interface = tokenizer.parse_token();
 819         if(!is_interface_qualifier(iface->interface))
 820                 throw parse_error(tokenizer.get_location(), iface->interface, "an interface qualifier");
 821
 822         iface->block_name = expect_identifier();
 823         iface->members = new Block;
 824         parse_block(*iface->members, true, &Parser::parse_variable_declaration_with_layout);
 825         if(!check(";"))
 826         {
 827                 iface->instance_name = expect_identifier();
 828                 if(check("["))
 829                 {
 830                         iface->array = true;
 831                         tokenizer.expect("]");
 832                 }
 833                 tokenizer.expect(";");
 834         }
 835
 836         return iface;
 837 }
 838
 839 RefPtr<Conditional> Parser::parse_conditional()
 840 {
 841         tokenizer.expect("if");
 842         RefPtr<Conditional> cond = create_node<Conditional>();
 843         tokenizer.expect("(");
 844         cond->condition = parse_expression();
 845         tokenizer.expect(")");
 846
 847         parse_block(cond->body, false, &Parser::parse_statement);
 848
 849         string token = tokenizer.peek_token();
 850         if(token=="else")
 851         {
 852                 tokenizer.parse_token();
 853                 parse_block(cond->else_body, false, &Parser::parse_statement);
 854         }
 855
 856         return cond;
 857 }
 858
 859 RefPtr<Iteration> Parser::parse_for()
 860 {
 861         tokenizer.expect("for");
 862         RefPtr<Iteration> loop = create_node<Iteration>();
 863         tokenizer.expect("(");
 864         string token = tokenizer.peek_token();
 865         if(is_type(token))
 866                 loop->init_statement = parse_statement();
 867         else
 868         {
 869                 if(token!=";")
 870                 {
 871                         RefPtr<ExpressionStatement> expr = create_node<ExpressionStatement>();
 872                         expr->expression = parse_expression();
 873                         loop->init_statement = expr;
 874                 }
 875                 tokenizer.expect(";");
 876         }
 877         if(tokenizer.peek_token()!=";")
 878                 loop->condition = parse_expression();
 879         tokenizer.expect(";");
 880         if(tokenizer.peek_token()!=")")
 881                 loop->loop_expression = parse_expression();
 882         tokenizer.expect(")");
 883
 884         parse_block(loop->body, false, &Parser::parse_statement);
 885
 886         return loop;
 887 }
 888
 889 RefPtr<Iteration> Parser::parse_while()
 890 {
 891         tokenizer.expect("while");
 892         RefPtr<Iteration> loop = create_node<Iteration>();
 893         tokenizer.expect("(");
 894         loop->condition = parse_expression();
 895         tokenizer.expect(")");
 896
 897         parse_block(loop->body, false, &Parser::parse_statement);
 898
 899         return loop;
 900 }
 901
 902 RefPtr<Passthrough> Parser::parse_passthrough()
 903 {
 904         tokenizer.expect("passthrough");
 905         RefPtr<Passthrough> pass = create_node<Passthrough>();
 906         if(cur_stage->type==Stage::GEOMETRY)
 907         {
 908                 tokenizer.expect("[");
 909                 pass->subscript = parse_expression();
 910                 tokenizer.expect("]");
 911         }
 912         tokenizer.expect(";");
 913         return pass;
 914 }
 915
 916 RefPtr<Return> Parser::parse_return()
 917 {
 918         tokenizer.expect("return");
 919         RefPtr<Return> ret = create_node<Return>();
 920         if(tokenizer.peek_token()!=";")
 921                 ret->expression = parse_expression();
 922         tokenizer.expect(";");
 923         return ret;
 924 }
 925
 926 } // namespace SL
 927 } // namespace GL
 928 } // namespace Msp