source/programcompiler.cpp

   1 #include <msp/core/raii.h>
   2 #include <msp/gl/extensions/ext_gpu_shader4.h>
   3 #include <msp/strings/format.h>
   4 #include <msp/strings/utils.h>
   5 #include "error.h"
   6 #include "program.h"
   7 #include "programcompiler.h"
   8 #include "resources.h"
   9 #include "shader.h"
  10
  11 using namespace std;
  12
  13 namespace {
  14
  15 const char builtins_src[] =
  16         "////// vertex\n"
  17         "out gl_PerVertex {\n"
  18         "  vec4 gl_Position;\n"
  19         "  float gl_ClipDistance[];\n"
  20         "};"
  21         "////// geometry\n"
  22         "in gl_PerVertex {\n"
  23         "  vec4 gl_Position;\n"
  24         "  float gl_ClipDistance[];\n"
  25         "} gl_in[];\n"
  26         "out gl_PerVertex {\n"
  27         "  vec4 gl_Position;\n"
  28         "  float gl_ClipDistance[];\n"
  29         "};\n";
  30
  31 }
  32
  33 namespace Msp {
  34 namespace GL {
  35
  36 using namespace ProgramSyntax;
  37
  38 ProgramCompiler::ProgramCompiler():
  39         resources(0),
  40         module(0)
  41 { }
  42
  43 void ProgramCompiler::compile(const string &source)
  44 {
  45         resources = 0;
  46         module = &parser.parse(source);
  47         process();
  48 }
  49
  50 void ProgramCompiler::compile(IO::Base &io, Resources *res)
  51 {
  52         resources = res;
  53         module = &parser.parse(io);
  54         process();
  55 }
  56
  57 void ProgramCompiler::add_shaders(Program &program)
  58 {
  59         if(!module)
  60                 throw invalid_operation("ProgramCompiler::add_shaders");
  61
  62         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
  63         {
  64                 if(i->type==VERTEX)
  65                 {
  66                         program.attach_shader_owned(new VertexShader(apply<Formatter>(*i)));
  67                         for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
  68                                 program.bind_attribute(j->second, j->first);
  69                 }
  70                 else if(i->type==GEOMETRY)
  71                         program.attach_shader_owned(new GeometryShader(apply<Formatter>(*i)));
  72                 else if(i->type==FRAGMENT)
  73                 {
  74                         program.attach_shader_owned(new FragmentShader(apply<Formatter>(*i)));
  75                         if(EXT_gpu_shader4)
  76                         {
  77                                 for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
  78                                         program.bind_fragment_data(j->second, j->first);
  79                         }
  80                 }
  81         }
  82 }
  83
  84 Module *ProgramCompiler::create_builtins_module()
  85 {
  86         ProgramParser parser;
  87         Module *module = new Module(parser.parse(builtins_src));
  88         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
  89         {
  90                 VariableResolver resolver;
  91                 i->content.visit(resolver);
  92                 for(map<string, VariableDeclaration *>::iterator j=i->content.variables.begin(); j!=i->content.variables.end(); ++j)
  93                         j->second->linked_declaration = j->second;
  94         }
  95         return module;
  96 }
  97
  98 Module &ProgramCompiler::get_builtins_module()
  99 {
 100         static RefPtr<Module> builtins_module = create_builtins_module();
 101         return *builtins_module;
 102 }
 103
 104 Stage *ProgramCompiler::get_builtins(StageType type)
 105 {
 106         Module &module = get_builtins_module();
 107         for(list<Stage>::iterator i=module.stages.begin(); i!=module.stages.end(); ++i)
 108                 if(i->type==type)
 109                         return &*i;
 110         return 0;
 111 }
 112
 113 void ProgramCompiler::process()
 114 {
 115         list<Import *> imports = apply<NodeGatherer<Import> >(module->shared);
 116         for(list<Import *>::iterator i=imports.end(); i!=imports.begin(); )
 117                 import((*--i)->module);
 118         apply<NodeRemover>(module->shared, set<Node *>(imports.begin(), imports.end()));
 119
 120         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 121                 generate(*i);
 122         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); )
 123         {
 124                 if(optimize(*i))
 125                         i = module->stages.begin();
 126                 else
 127                         ++i;
 128         }
 129         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 130                 finalize(*i);
 131 }
 132
 133 void ProgramCompiler::import(const string &name)
 134 {
 135         string fn = name+".glsl";
 136         RefPtr<IO::Seekable> io = (resources ? resources->open_raw(fn) : Resources::get_builtins().open(fn));
 137         if(!io)
 138                 throw runtime_error(format("module %s not found", name));
 139         ProgramParser import_parser;
 140         Module &imported_module = import_parser.parse(*io);
 141
 142         inject_block(module->shared.content, imported_module.shared.content);
 143         apply<DeclarationCombiner>(module->shared);
 144         for(list<Stage>::iterator i=imported_module.stages.begin(); i!=imported_module.stages.end(); ++i)
 145         {
 146                 list<Stage>::iterator j;
 147                 for(j=module->stages.begin(); (j!=module->stages.end() && j->type<i->type); ++j) ;
 148                 if(j==module->stages.end() || j->type>i->type)
 149                 {
 150                         j = module->stages.insert(j, *i);
 151                         list<Stage>::iterator k = j;
 152                         if(++k!=module->stages.end())
 153                                 k->previous = &*j;
 154                         if(j!=module->stages.begin())
 155                                 j->previous = &*--(k=j);
 156                 }
 157                 else
 158                 {
 159                         inject_block(j->content, i->content);
 160                         apply<DeclarationCombiner>(*j);
 161                 }
 162         }
 163 }
 164
 165 void ProgramCompiler::generate(Stage &stage)
 166 {
 167         inject_block(stage.content, module->shared.content);
 168
 169         apply<DeclarationReorderer>(stage);
 170         apply<FunctionResolver>(stage);
 171         apply<VariableResolver>(stage);
 172         apply<InterfaceGenerator>(stage);
 173         apply<VariableResolver>(stage);
 174         apply<VariableRenamer>(stage);
 175         apply<DeclarationReorderer>(stage);
 176         apply<LegacyConverter>(stage);
 177 }
 178
 179 bool ProgramCompiler::optimize(Stage &stage)
 180 {
 181         apply<ConstantConditionEliminator>(stage);
 182
 183         set<FunctionDeclaration *> inlineable = apply<InlineableFunctionLocator>(stage);
 184         apply<FunctionInliner>(stage, inlineable);
 185
 186         set<Node *> unused = apply<UnusedVariableLocator>(stage);
 187         set<Node *> unused2 = apply<UnusedFunctionLocator>(stage);
 188         unused.insert(unused2.begin(), unused2.end());
 189         apply<NodeRemover>(stage, unused);
 190
 191         return !unused.empty();
 192 }
 193
 194 void ProgramCompiler::finalize(Stage &stage)
 195 {
 196         if(get_gl_api()==OPENGL_ES2)
 197                 apply<DefaultPrecisionGenerator>(stage);
 198         else
 199                 apply<PrecisionRemover>(stage);
 200 }
 201
 202 void ProgramCompiler::inject_block(Block &target, const Block &source)
 203 {
 204         list<RefPtr<Node> >::iterator insert_point = target.body.begin();
 205         for(list<RefPtr<Node> >::const_iterator i=source.body.begin(); i!=source.body.end(); ++i)
 206                 target.body.insert(insert_point, (*i)->clone());
 207 }
 208
 209 template<typename T>
 210 typename T::ResultType ProgramCompiler::apply(Stage &stage)
 211 {
 212         T visitor;
 213         visitor.apply(stage);
 214         return visitor.get_result();
 215 }
 216
 217 template<typename T, typename A>
 218 typename T::ResultType ProgramCompiler::apply(Stage &stage, const A &arg)
 219 {
 220         T visitor(arg);
 221         visitor.apply(stage);
 222         return visitor.get_result();
 223 }
 224
 225
 226 ProgramCompiler::Visitor::Visitor():
 227         stage(0)
 228 { }
 229
 230 void ProgramCompiler::Visitor::apply(Stage &s)
 231 {
 232         SetForScope<Stage *> set(stage, &s);
 233         stage->content.visit(*this);
 234 }
 235
 236
 237 ProgramCompiler::BlockModifier::BlockModifier():
 238         remove_node(false)
 239 { }
 240
 241 void ProgramCompiler::BlockModifier::flatten_block(Block &block)
 242 {
 243         insert_nodes.insert(insert_nodes.end(), block.body.begin(), block.body.end());
 244         remove_node = true;
 245 }
 246
 247 void ProgramCompiler::BlockModifier::apply_and_increment(Block &block, list<RefPtr<Node> >::iterator &i)
 248 {
 249         block.body.insert(i, insert_nodes.begin(), insert_nodes.end());
 250         insert_nodes.clear();
 251
 252         if(remove_node)
 253                 block.body.erase(i++);
 254         else
 255                 ++i;
 256         remove_node = false;
 257 }
 258
 259 void ProgramCompiler::BlockModifier::visit(Block &block)
 260 {
 261         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 262         {
 263                 (*i)->visit(*this);
 264                 apply_and_increment(block, i);
 265         }
 266 }
 267
 268
 269 ProgramCompiler::Formatter::Formatter():
 270         indent(0),
 271         parameter_list(false),
 272         else_if(0)
 273 { }
 274
 275 void ProgramCompiler::Formatter::apply(ProgramSyntax::Stage &s)
 276 {
 277         GLApi api = get_gl_api();
 278         const Version &ver = s.required_version;
 279
 280         if(ver)
 281         {
 282                 formatted += format("#version %d%02d", ver.major, ver.minor);
 283                 if(api==OPENGL_ES2 && ver>=Version(3, 0))
 284                         formatted += " es";
 285                 formatted += '\n';
 286         }
 287
 288         Visitor::apply(s);
 289 }
 290
 291 void ProgramCompiler::Formatter::visit(Literal &literal)
 292 {
 293         formatted += literal.token;
 294 }
 295
 296 void ProgramCompiler::Formatter::visit(ParenthesizedExpression &parexpr)
 297 {
 298         formatted += '(';
 299         parexpr.expression->visit(*this);
 300         formatted += ')';
 301 }
 302
 303 void ProgramCompiler::Formatter::visit(VariableReference &var)
 304 {
 305         formatted += var.name;
 306 }
 307
 308 void ProgramCompiler::Formatter::visit(MemberAccess &memacc)
 309 {
 310         memacc.left->visit(*this);
 311         formatted += format(".%s", memacc.member);
 312 }
 313
 314 void ProgramCompiler::Formatter::visit(UnaryExpression &unary)
 315 {
 316         if(unary.prefix)
 317                 formatted += unary.oper;
 318         unary.expression->visit(*this);
 319         if(!unary.prefix)
 320                 formatted += unary.oper;
 321 }
 322
 323 void ProgramCompiler::Formatter::visit(BinaryExpression &binary)
 324 {
 325         binary.left->visit(*this);
 326         formatted += binary.oper;
 327         binary.right->visit(*this);
 328         formatted += binary.after;
 329 }
 330
 331 void ProgramCompiler::Formatter::visit(Assignment &assign)
 332 {
 333         assign.left->visit(*this);
 334         formatted += format(" %s ", assign.oper);
 335         assign.right->visit(*this);
 336 }
 337
 338 void ProgramCompiler::Formatter::visit(FunctionCall &call)
 339 {
 340         formatted += format("%s(", call.name);
 341         for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
 342         {
 343                 if(i!=call.arguments.begin())
 344                         formatted += ", ";
 345                 (*i)->visit(*this);
 346         }
 347         formatted += ')';
 348 }
 349
 350 void ProgramCompiler::Formatter::visit(ExpressionStatement &expr)
 351 {
 352         expr.expression->visit(*this);
 353         formatted += ';';
 354 }
 355
 356 void ProgramCompiler::Formatter::visit(Block &block)
 357 {
 358         if(else_if)
 359                 --else_if;
 360
 361         unsigned brace_indent = indent;
 362         bool use_braces = (block.use_braces || (indent && block.body.size()!=1));
 363         if(use_braces)
 364                 formatted += format("%s{\n", string(brace_indent*2, ' '));
 365
 366         SetForScope<unsigned> set(indent, indent+(indent>0 || use_braces));
 367         string spaces(indent*2, ' ');
 368         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 369         {
 370                 if(i!=block.body.begin())
 371                         formatted += '\n';
 372                 formatted += spaces;
 373                 (*i)->visit(*this);
 374                 else_if = 0;
 375         }
 376
 377         if(use_braces)
 378                 formatted += format("\n%s}", string(brace_indent*2, ' '));
 379 }
 380
 381 void ProgramCompiler::Formatter::visit(Import &import)
 382 {
 383         formatted += format("import %s;", import.module);
 384 }
 385
 386 void ProgramCompiler::Formatter::visit(Precision &prec)
 387 {
 388         formatted += format("precision %s %s;", prec.precision, prec.type);
 389 }
 390
 391 void ProgramCompiler::Formatter::visit(Layout &layout)
 392 {
 393         formatted += "layout(";
 394         for(vector<Layout::Qualifier>::const_iterator i=layout.qualifiers.begin(); i!=layout.qualifiers.end(); ++i)
 395         {
 396                 if(i!=layout.qualifiers.begin())
 397                         formatted += ", ";
 398                 formatted += i->identifier;
 399                 if(!i->value.empty())
 400                         formatted += format("=%s", i->value);
 401         }
 402         formatted += ')';
 403 }
 404
 405 void ProgramCompiler::Formatter::visit(InterfaceLayout &layout)
 406 {
 407         layout.layout.visit(*this);
 408         formatted += format(" %s;", layout.interface);
 409 }
 410
 411 void ProgramCompiler::Formatter::visit(StructDeclaration &strct)
 412 {
 413         formatted += format("struct %s\n", strct.name);
 414         strct.members.visit(*this);
 415         formatted += ';';
 416 }
 417
 418 void ProgramCompiler::Formatter::visit(VariableDeclaration &var)
 419 {
 420         if(var.layout)
 421         {
 422                 var.layout->visit(*this);
 423                 formatted += ' ';
 424         }
 425         if(var.constant)
 426                 formatted += "const ";
 427         if(!var.sampling.empty())
 428                 formatted += format("%s ", var.sampling);
 429         if(!var.interface.empty() && var.interface!=block_interface)
 430         {
 431                 string interface = var.interface;
 432                 if(stage->required_version<Version(1, 30))
 433                 {
 434                         if(stage->type==VERTEX && var.interface=="in")
 435                                 interface = "attribute";
 436                         else if((stage->type==VERTEX && var.interface=="out") || (stage->type==FRAGMENT && var.interface=="in"))
 437                                 interface = "varying";
 438                 }
 439                 formatted += format("%s ", interface);
 440         }
 441         if(!var.precision.empty())
 442                 formatted += format("%s ", var.precision);
 443         formatted += format("%s %s", var.type, var.name);
 444         if(var.array)
 445         {
 446                 formatted += '[';
 447                 if(var.array_size)
 448                         var.array_size->visit(*this);
 449                 formatted += ']';
 450         }
 451         if(var.init_expression)
 452         {
 453                 formatted += " = ";
 454                 var.init_expression->visit(*this);
 455         }
 456         if(!parameter_list)
 457                 formatted += ';';
 458 }
 459
 460 void ProgramCompiler::Formatter::visit(InterfaceBlock &iface)
 461 {
 462         SetForScope<string> set(block_interface, iface.interface);
 463         formatted += format("%s %s\n", iface.interface, iface.name);
 464         iface.members.visit(*this);
 465         formatted += ';';
 466 }
 467
 468 void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 469 {
 470         formatted += format("%s %s(", func.return_type, func.name);
 471         for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 472         {
 473                 if(i!=func.parameters.begin())
 474                         formatted += ", ";
 475                 SetFlag set(parameter_list);
 476                 (*i)->visit(*this);
 477         }
 478         formatted += ')';
 479         if(func.definition==&func)
 480         {
 481                 formatted += '\n';
 482                 func.body.visit(*this);
 483         }
 484         else
 485                 formatted += ';';
 486 }
 487
 488 void ProgramCompiler::Formatter::visit(Conditional &cond)
 489 {
 490         if(else_if)
 491                 formatted.replace(formatted.rfind('\n'), string::npos, 1, ' ');
 492
 493         indent -= else_if;
 494
 495         formatted += "if(";
 496         cond.condition->visit(*this);
 497         formatted += ")\n";
 498
 499         cond.body.visit(*this);
 500         if(!cond.else_body.body.empty())
 501         {
 502                 formatted += format("\n%selse\n", string(indent*2, ' '));
 503                 SetForScope<unsigned> set(else_if, 2);
 504                 cond.else_body.visit(*this);
 505         }
 506 }
 507
 508 void ProgramCompiler::Formatter::visit(Iteration &iter)
 509 {
 510         formatted += "for(";
 511         iter.init_statement->visit(*this);
 512         formatted += ' ';
 513         iter.condition->visit(*this);
 514         formatted += "; ";
 515         iter.loop_expression->visit(*this);
 516         formatted += ")\n";
 517         iter.body.visit(*this);
 518 }
 519
 520 void ProgramCompiler::Formatter::visit(Return &ret)
 521 {
 522         formatted += "return ";
 523         ret.expression->visit(*this);
 524         formatted += ';';
 525 }
 526
 527 void ProgramCompiler::Formatter::visit(Jump &jump)
 528 {
 529         formatted += jump.keyword;
 530         formatted += ';';
 531 }
 532
 533
 534 ProgramCompiler::DeclarationCombiner::DeclarationCombiner():
 535         toplevel(true)
 536 { }
 537
 538 void ProgramCompiler::DeclarationCombiner::visit(Block &block)
 539 {
 540         if(!toplevel)
 541                 return;
 542
 543         SetForScope<bool> set(toplevel, false);
 544         BlockModifier::visit(block);
 545 }
 546
 547 void ProgramCompiler::DeclarationCombiner::visit(FunctionDeclaration &func)
 548 {
 549         vector<FunctionDeclaration *> &decls = functions[func.name];
 550         if(func.definition)
 551         {
 552                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 553                 {
 554                         (*i)->definition = func.definition;
 555                         (*i)->body.body.clear();
 556                 }
 557         }
 558         decls.push_back(&func);
 559 }
 560
 561 void ProgramCompiler::DeclarationCombiner::visit(VariableDeclaration &var)
 562 {
 563         VariableDeclaration *&ptr = variables[var.name];
 564         if(ptr)
 565         {
 566                 ptr->type = var.type;
 567                 if(var.init_expression)
 568                         ptr->init_expression = var.init_expression;
 569                 remove_node = true;
 570         }
 571         else
 572                 ptr = &var;
 573 }
 574
 575
 576 ProgramCompiler::VariableResolver::VariableResolver():
 577         anonymous(false),
 578         record_target(false),
 579         assignment_target(0),
 580         self_referencing(false)
 581 { }
 582
 583 void ProgramCompiler::VariableResolver::apply(Stage &s)
 584 {
 585         SetForScope<Stage *> set(stage, &s);
 586         Stage *builtins = get_builtins(stage->type);
 587         if(builtins)
 588                 blocks.push_back(&builtins->content);
 589         stage->content.visit(*this);
 590         if(builtins)
 591                 blocks.pop_back();
 592 }
 593
 594 void ProgramCompiler::VariableResolver::visit(Block &block)
 595 {
 596         blocks.push_back(&block);
 597         block.variables.clear();
 598         TraversingVisitor::visit(block);
 599         blocks.pop_back();
 600 }
 601
 602 void ProgramCompiler::VariableResolver::visit(VariableReference &var)
 603 {
 604         var.declaration = 0;
 605         type = 0;
 606         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 607         {
 608                 --i;
 609                 map<string, VariableDeclaration *>::iterator j = (*i)->variables.find(var.name);
 610                 if(j!=(*i)->variables.end())
 611                 {
 612                         var.declaration = j->second;
 613                         type = j->second->type_declaration;
 614                         break;
 615                 }
 616         }
 617
 618         if(record_target)
 619         {
 620                 if(assignment_target)
 621                 {
 622                         record_target = false;
 623                         assignment_target = 0;
 624                 }
 625                 else
 626                         assignment_target = var.declaration;
 627         }
 628         else if(var.declaration && var.declaration==assignment_target)
 629                 self_referencing = true;
 630 }
 631
 632 void ProgramCompiler::VariableResolver::visit(MemberAccess &memacc)
 633 {
 634         type = 0;
 635         TraversingVisitor::visit(memacc);
 636         memacc.declaration = 0;
 637         if(type)
 638         {
 639                 map<string, VariableDeclaration *>::iterator i = type->members.variables.find(memacc.member);
 640                 if(i!=type->members.variables.end())
 641                 {
 642                         memacc.declaration = i->second;
 643                         type = i->second->type_declaration;
 644                 }
 645                 else
 646                         type = 0;
 647         }
 648 }
 649
 650 void ProgramCompiler::VariableResolver::visit(BinaryExpression &binary)
 651 {
 652         if(binary.oper=="[")
 653         {
 654                 {
 655                         SetForScope<bool> set(record_target, false);
 656                         binary.right->visit(*this);
 657                 }
 658                 type = 0;
 659                 binary.left->visit(*this);
 660         }
 661         else
 662         {
 663                 TraversingVisitor::visit(binary);
 664                 type = 0;
 665         }
 666 }
 667
 668 void ProgramCompiler::VariableResolver::visit(Assignment &assign)
 669 {
 670         {
 671                 SetFlag set(record_target);
 672                 assignment_target = 0;
 673                 assign.left->visit(*this);
 674         }
 675
 676         self_referencing = false;
 677         assign.right->visit(*this);
 678
 679         assign.self_referencing = (self_referencing || assign.oper!="=");
 680         assign.target_declaration = assignment_target;
 681 }
 682
 683 void ProgramCompiler::VariableResolver::visit(StructDeclaration &strct)
 684 {
 685         TraversingVisitor::visit(strct);
 686         blocks.back()->types[strct.name] = &strct;
 687 }
 688
 689 void ProgramCompiler::VariableResolver::visit(VariableDeclaration &var)
 690 {
 691         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 692         {
 693                 --i;
 694                 map<string, StructDeclaration *>::iterator j = (*i)->types.find(var.type);
 695                 if(j!=(*i)->types.end())
 696                         var.type_declaration = j->second;
 697         }
 698
 699         if(!block_interface.empty() && var.interface.empty())
 700                 var.interface = block_interface;
 701
 702         TraversingVisitor::visit(var);
 703         blocks.back()->variables[var.name] = &var;
 704         if(anonymous && blocks.size()>1)
 705                 blocks[blocks.size()-2]->variables[var.name] = &var;
 706 }
 707
 708 void ProgramCompiler::VariableResolver::visit(InterfaceBlock &iface)
 709 {
 710         SetFlag set(anonymous);
 711         SetForScope<string> set2(block_interface, iface.interface);
 712         TraversingVisitor::visit(iface);
 713 }
 714
 715
 716 void ProgramCompiler::FunctionResolver::visit(FunctionCall &call)
 717 {
 718         map<string, vector<FunctionDeclaration *> >::iterator i = functions.find(call.name);
 719         if(i!=functions.end())
 720                 call.declaration = i->second.back();
 721
 722         TraversingVisitor::visit(call);
 723 }
 724
 725 void ProgramCompiler::FunctionResolver::visit(FunctionDeclaration &func)
 726 {
 727         vector<FunctionDeclaration *> &decls = functions[func.name];
 728         if(func.definition)
 729         {
 730                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 731                         (*i)->definition = func.definition;
 732                 decls.clear();
 733                 decls.push_back(&func);
 734         }
 735         else if(!decls.empty() && decls.back()->definition)
 736                 func.definition = decls.back()->definition;
 737         else
 738                 decls.push_back(&func);
 739
 740         TraversingVisitor::visit(func);
 741 }
 742
 743
 744 ProgramCompiler::InterfaceGenerator::InterfaceGenerator():
 745         scope_level(0)
 746 { }
 747
 748 string ProgramCompiler::InterfaceGenerator::get_out_prefix(StageType type)
 749 {
 750         if(type==VERTEX)
 751                 return "_vs_out_";
 752         else if(type==GEOMETRY)
 753                 return "_gs_out_";
 754         else
 755                 return string();
 756 }
 757
 758 void ProgramCompiler::InterfaceGenerator::apply(Stage &s)
 759 {
 760         SetForScope<Stage *> set(stage, &s);
 761         if(stage->previous)
 762                 in_prefix = get_out_prefix(stage->previous->type);
 763         out_prefix = get_out_prefix(stage->type);
 764         stage->content.visit(*this);
 765 }
 766
 767 void ProgramCompiler::InterfaceGenerator::visit(Block &block)
 768 {
 769         SetForScope<unsigned> set(scope_level, scope_level+1);
 770         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 771         {
 772                 (*i)->visit(*this);
 773
 774                 if(scope_level==1)
 775                 {
 776                         for(map<string, RefPtr<VariableDeclaration> >::iterator j=iface_declarations.begin(); j!=iface_declarations.end(); ++j)
 777                         {
 778                                 list<RefPtr<Node> >::iterator k = block.body.insert(i, j->second);
 779                                 (*k)->visit(*this);
 780                         }
 781                         iface_declarations.clear();
 782                 }
 783
 784                 apply_and_increment(block, i);
 785         }
 786 }
 787
 788 string ProgramCompiler::InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
 789 {
 790         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
 791         return prefix+name.substr(offset);
 792 }
 793
 794 bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
 795 {
 796         const map<string, VariableDeclaration *> &stage_vars = (iface=="in" ? stage->in_variables : stage->out_variables);
 797         if(stage_vars.count(name) || iface_declarations.count(name))
 798                 return false;
 799
 800         VariableDeclaration* iface_var = new VariableDeclaration;
 801         iface_var->sampling = var.sampling;
 802         iface_var->interface = iface;
 803         iface_var->type = var.type;
 804         iface_var->type_declaration = var.type_declaration;
 805         iface_var->name = name;
 806         if(stage->type==GEOMETRY)
 807                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
 808         else
 809                 iface_var->array = var.array;
 810         if(iface_var->array)
 811                 iface_var->array_size = var.array_size;
 812         if(iface=="in")
 813                 iface_var->linked_declaration = &var;
 814         iface_declarations[name] = iface_var;
 815
 816         return true;
 817 }
 818
 819 void ProgramCompiler::InterfaceGenerator::insert_assignment(const string &left, ProgramSyntax::Expression *right)
 820 {
 821         Assignment *assign = new Assignment;
 822         VariableReference *ref = new VariableReference;
 823         ref->name = left;
 824         assign->left = ref;
 825         assign->oper = "=";
 826         assign->right = right;
 827
 828         ExpressionStatement *stmt = new ExpressionStatement;
 829         stmt->expression = assign;
 830         insert_nodes.push_back(stmt);
 831 }
 832
 833 void ProgramCompiler::InterfaceGenerator::visit(VariableReference &var)
 834 {
 835         if(var.declaration || !stage->previous)
 836                 return;
 837         if(iface_declarations.count(var.name))
 838                 return;
 839
 840         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 841         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
 842         if(i==prev_out.end())
 843                 i = prev_out.find(in_prefix+var.name);
 844         if(i!=prev_out.end())
 845                 generate_interface(*i->second, "in", var.name);
 846 }
 847
 848 void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &var)
 849 {
 850         if(var.interface=="out")
 851         {
 852                 if(scope_level==1)
 853                         stage->out_variables[var.name] = &var;
 854                 else if(generate_interface(var, "out", change_prefix(var.name, string())))
 855                 {
 856                         remove_node = true;
 857                         if(var.init_expression)
 858                                 insert_assignment(var.name, var.init_expression->clone());
 859                 }
 860         }
 861         else if(var.interface=="in")
 862         {
 863                 stage->in_variables[var.name] = &var;
 864                 if(var.linked_declaration)
 865                         var.linked_declaration->linked_declaration = &var;
 866                 else if(stage->previous)
 867                 {
 868                         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 869                         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
 870                         if(i!=prev_out.end())
 871                         {
 872                                 var.linked_declaration = i->second;
 873                                 i->second->linked_declaration = &var;
 874                         }
 875                 }
 876         }
 877
 878         TraversingVisitor::visit(var);
 879 }
 880
 881 void ProgramCompiler::InterfaceGenerator::visit(Passthrough &pass)
 882 {
 883         vector<VariableDeclaration *> pass_vars;
 884
 885         for(map<string, VariableDeclaration *>::const_iterator i=stage->in_variables.begin(); i!=stage->in_variables.end(); ++i)
 886                 pass_vars.push_back(i->second);
 887         for(map<string, RefPtr<VariableDeclaration> >::const_iterator i=iface_declarations.begin(); i!=iface_declarations.end(); ++i)
 888                 if(i->second->interface=="in")
 889                         pass_vars.push_back(i->second.get());
 890
 891         if(stage->previous)
 892         {
 893                 const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 894                 for(map<string, VariableDeclaration *>::const_iterator i=prev_out.begin(); i!=prev_out.end(); ++i)
 895                 {
 896                         bool linked = false;
 897                         for(vector<VariableDeclaration *>::const_iterator j=pass_vars.begin(); (!linked && j!=pass_vars.end()); ++j)
 898                                 linked = ((*j)->linked_declaration==i->second);
 899
 900                         if(!linked && generate_interface(*i->second, "in", i->second->name))
 901                                 pass_vars.push_back(i->second);
 902                 }
 903         }
 904
 905         if(stage->type==GEOMETRY)
 906         {
 907                 VariableReference *ref = new VariableReference;
 908                 ref->name = "gl_in";
 909
 910                 BinaryExpression *subscript = new BinaryExpression;
 911                 subscript->left = ref;
 912                 subscript->oper = "[";
 913                 subscript->right = pass.subscript;
 914                 subscript->after = "]";
 915
 916                 MemberAccess *memacc = new MemberAccess;
 917                 memacc->left = subscript;
 918                 memacc->member = "gl_Position";
 919
 920                 insert_assignment("gl_Position", memacc);
 921         }
 922
 923         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
 924         {
 925                 string out_name = change_prefix((*i)->name, out_prefix);
 926                 generate_interface(**i, "out", out_name);
 927
 928                 VariableReference *ref = new VariableReference;
 929                 ref->name = (*i)->name;
 930                 if(pass.subscript)
 931                 {
 932                         BinaryExpression *subscript = new BinaryExpression;
 933                         subscript->left = ref;
 934                         subscript->oper = "[";
 935                         subscript->right = pass.subscript;
 936                         subscript->after = "]";
 937                         insert_assignment(out_name, subscript);
 938                 }
 939                 else
 940                         insert_assignment(out_name, ref);
 941         }
 942
 943         remove_node = true;
 944 }
 945
 946
 947 void ProgramCompiler::VariableRenamer::visit(VariableReference &var)
 948 {
 949         if(var.declaration)
 950                 var.name = var.declaration->name;
 951 }
 952
 953 void ProgramCompiler::VariableRenamer::visit(VariableDeclaration &var)
 954 {
 955         if(var.linked_declaration)
 956                 var.name = var.linked_declaration->name;
 957         TraversingVisitor::visit(var);
 958 }
 959
 960
 961 ProgramCompiler::DeclarationReorderer::DeclarationReorderer():
 962         kind(NO_DECLARATION)
 963 { }
 964
 965 void ProgramCompiler::DeclarationReorderer::visit(Block &block)
 966 {
 967         list<RefPtr<Node> >::iterator struct_insert_point = block.body.end();
 968         list<RefPtr<Node> >::iterator variable_insert_point = block.body.end();
 969
 970         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 971         {
 972                 kind = NO_DECLARATION;
 973                 (*i)->visit(*this);
 974
 975                 bool moved = false;
 976                 if(kind==STRUCT && struct_insert_point!=block.body.end())
 977                 {
 978                         block.body.insert(struct_insert_point, *i);
 979                         moved = true;
 980                 }
 981                 else if(kind>STRUCT && struct_insert_point==block.body.end())
 982                         struct_insert_point = i;
 983
 984                 if(kind==VARIABLE && variable_insert_point!=block.body.end())
 985                 {
 986                         block.body.insert(variable_insert_point, *i);
 987                         moved = true;
 988                 }
 989                 else if(kind>VARIABLE && variable_insert_point==block.body.end())
 990                         variable_insert_point = i;
 991
 992                 if(moved)
 993                         block.body.erase(i++);
 994                 else
 995                         ++i;
 996         }
 997 }
 998
 999
1000 ProgramCompiler::InlineableFunctionLocator::InlineableFunctionLocator():
1001         in_function(0)
1002 { }
1003
1004 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionCall &call)
1005 {
1006         FunctionDeclaration *def = call.declaration;
1007         if(def && def->definition!=def)
1008                 def = def->definition;
1009
1010         if(def)
1011         {
1012                 unsigned &count = refcounts[def];
1013                 ++count;
1014                 if(count>1 || def==in_function)
1015                         inlineable.erase(def);
1016         }
1017
1018         TraversingVisitor::visit(call);
1019 }
1020
1021 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionDeclaration &func)
1022 {
1023         unsigned &count = refcounts[func.definition];
1024         if(!count && func.parameters.empty())
1025                 inlineable.insert(func.definition);
1026
1027         SetForScope<FunctionDeclaration *> set(in_function, &func);
1028         TraversingVisitor::visit(func);
1029 }
1030
1031
1032 ProgramCompiler::FunctionInliner::FunctionInliner():
1033         extract_result(0)
1034 { }
1035
1036 ProgramCompiler::FunctionInliner::FunctionInliner(const set<FunctionDeclaration *> &in):
1037         inlineable(in),
1038         extract_result(0)
1039 { }
1040
1041 void ProgramCompiler::FunctionInliner::visit_and_inline(RefPtr<Expression> &ptr)
1042 {
1043         inline_result = 0;
1044         ptr->visit(*this);
1045         if(inline_result)
1046                 ptr = inline_result;
1047 }
1048
1049 void ProgramCompiler::FunctionInliner::visit(Block &block)
1050 {
1051         if(extract_result)
1052                 --extract_result;
1053
1054         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
1055         {
1056                 (*i)->visit(*this);
1057                 if(extract_result)
1058                         --extract_result;
1059         }
1060 }
1061
1062 void ProgramCompiler::FunctionInliner::visit(UnaryExpression &unary)
1063 {
1064         visit_and_inline(unary.expression);
1065         inline_result = 0;
1066 }
1067
1068 void ProgramCompiler::FunctionInliner::visit(BinaryExpression &binary)
1069 {
1070         visit_and_inline(binary.left);
1071         visit_and_inline(binary.right);
1072         inline_result = 0;
1073 }
1074
1075 void ProgramCompiler::FunctionInliner::visit(FunctionCall &call)
1076 {
1077         for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
1078                 visit_and_inline(*i);
1079
1080         FunctionDeclaration *def = call.declaration;
1081         if(def && def->definition!=def)
1082                 def = def->definition;
1083
1084         if(def && inlineable.count(def))
1085         {
1086                 extract_result = 2;
1087                 def->visit(*this);
1088         }
1089         else
1090                 inline_result = 0;
1091 }
1092
1093 void ProgramCompiler::FunctionInliner::visit(Return &ret)
1094 {
1095         TraversingVisitor::visit(ret);
1096
1097         if(extract_result)
1098                 inline_result = ret.expression->clone();
1099 }
1100
1101
1102 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator():
1103         variable_values(0),
1104         result(0.0f),
1105         result_valid(false)
1106 { }
1107
1108 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator(const ValueMap &v):
1109         variable_values(&v),
1110         result(0.0f),
1111         result_valid(false)
1112 { }
1113
1114 void ProgramCompiler::ExpressionEvaluator::visit(Literal &literal)
1115 {
1116         if(literal.token=="true")
1117                 result = 1.0f;
1118         else if(literal.token=="false")
1119                 result = 0.0f;
1120         else
1121                 result = lexical_cast<float>(literal.token);
1122         result_valid = true;
1123 }
1124
1125 void ProgramCompiler::ExpressionEvaluator::visit(ParenthesizedExpression &parexp)
1126 {
1127         parexp.expression->visit(*this);
1128 }
1129
1130 void ProgramCompiler::ExpressionEvaluator::visit(VariableReference &var)
1131 {
1132         if(!var.declaration)
1133                 return;
1134
1135         if(variable_values)
1136         {
1137                 ValueMap::const_iterator i = variable_values->find(var.declaration);
1138                 if(i!=variable_values->end())
1139                         i->second->visit(*this);
1140         }
1141         else if(var.declaration->init_expression)
1142                 var.declaration->init_expression->visit(*this);
1143 }
1144
1145 void ProgramCompiler::ExpressionEvaluator::visit(UnaryExpression &unary)
1146 {
1147         result_valid = false;
1148         unary.expression->visit(*this);
1149         if(!result_valid)
1150                 return;
1151
1152         if(unary.oper=="!")
1153                 result = !result;
1154         else
1155                 result_valid = false;
1156 }
1157
1158 void ProgramCompiler::ExpressionEvaluator::visit(BinaryExpression &binary)
1159 {
1160         result_valid = false;
1161         binary.left->visit(*this);
1162         if(!result_valid)
1163                 return;
1164
1165         float left_result = result;
1166         result_valid = false;
1167         binary.right->visit(*this);
1168         if(!result_valid)
1169                 return;
1170
1171         if(binary.oper=="<")
1172                 result = (left_result<result);
1173         else if(binary.oper=="<=")
1174                 result = (left_result<=result);
1175         else if(binary.oper==">")
1176                 result = (left_result>result);
1177         else if(binary.oper==">=")
1178                 result = (left_result>=result);
1179         else if(binary.oper=="==")
1180                 result = (left_result==result);
1181         else if(binary.oper=="!=")
1182                 result = (left_result!=result);
1183         else if(binary.oper=="&&")
1184                 result = (left_result && result);
1185         else if(binary.oper=="||")
1186                 result = (left_result || result);
1187         else
1188                 result_valid = false;
1189 }
1190
1191
1192 ProgramCompiler::ConstantConditionEliminator::ConstantConditionEliminator():
1193         scope_level(0)
1194 { }
1195
1196 void ProgramCompiler::ConstantConditionEliminator::visit(Block &block)
1197 {
1198         SetForScope<unsigned> set(scope_level, scope_level+1);
1199         BlockModifier::visit(block);
1200
1201         for(map<string, VariableDeclaration *>::const_iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
1202                 variable_values.erase(i->second);
1203 }
1204
1205 void ProgramCompiler::ConstantConditionEliminator::visit(Assignment &assign)
1206 {
1207         variable_values.erase(assign.target_declaration);
1208 }
1209
1210 void ProgramCompiler::ConstantConditionEliminator::visit(VariableDeclaration &var)
1211 {
1212         if(var.constant || scope_level>1)
1213                 variable_values[&var] = var.init_expression.get();
1214 }
1215
1216 void ProgramCompiler::ConstantConditionEliminator::visit(Conditional &cond)
1217 {
1218         ExpressionEvaluator eval(variable_values);
1219         cond.condition->visit(eval);
1220         if(eval.result_valid)
1221                 flatten_block(eval.result ? cond.body : cond.else_body);
1222         else
1223                 TraversingVisitor::visit(cond);
1224 }
1225
1226 void ProgramCompiler::ConstantConditionEliminator::visit(Iteration &iter)
1227 {
1228         if(iter.condition)
1229         {
1230                 ExpressionEvaluator eval;
1231                 iter.condition->visit(eval);
1232                 if(eval.result_valid && !eval.result)
1233                 {
1234                         remove_node = true;
1235                         return;
1236                 }
1237         }
1238
1239         TraversingVisitor::visit(iter);
1240 }
1241
1242
1243 ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
1244         aggregate(0),
1245         assignment(0),
1246         assignment_target(false),
1247         global_scope(true)
1248 { }
1249
1250 void ProgramCompiler::UnusedVariableLocator::apply(Stage &s)
1251 {
1252         variables.push_back(BlockVariableMap());
1253         Visitor::apply(s);
1254         BlockVariableMap &global_variables = variables.back();
1255         for(BlockVariableMap::iterator i=global_variables.begin(); i!=global_variables.end(); ++i)
1256         {
1257                 if(i->first->interface=="out" && (s.type==FRAGMENT || i->first->linked_declaration || !i->first->name.compare(0, 3, "gl_")))
1258                         continue;
1259                 if(!i->second.referenced)
1260                 {
1261                         unused_nodes.insert(i->first);
1262                         clear_assignments(i->second, true);
1263                 }
1264         }
1265         variables.pop_back();
1266 }
1267
1268 void ProgramCompiler::UnusedVariableLocator::visit(VariableReference &var)
1269 {
1270         map<VariableDeclaration *, Node *>::iterator i = aggregates.find(var.declaration);
1271         if(i!=aggregates.end())
1272                 unused_nodes.erase(i->second);
1273
1274         if(var.declaration && !assignment_target)
1275         {
1276                 VariableInfo &var_info = variables.back()[var.declaration];
1277                 var_info.assignments.clear();
1278                 var_info.referenced = true;
1279         }
1280 }
1281
1282 void ProgramCompiler::UnusedVariableLocator::visit(MemberAccess &memacc)
1283 {
1284         TraversingVisitor::visit(memacc);
1285         unused_nodes.erase(memacc.declaration);
1286 }
1287
1288 void ProgramCompiler::UnusedVariableLocator::visit(BinaryExpression &binary)
1289 {
1290         if(binary.oper=="[")
1291         {
1292                 binary.left->visit(*this);
1293                 SetForScope<bool> set(assignment_target, false);
1294                 binary.right->visit(*this);
1295         }
1296         else
1297                 TraversingVisitor::visit(binary);
1298 }
1299
1300 void ProgramCompiler::UnusedVariableLocator::visit(Assignment &assign)
1301 {
1302         {
1303                 SetForScope<bool> set(assignment_target, !assign.self_referencing);
1304                 assign.left->visit(*this);
1305         }
1306         assign.right->visit(*this);
1307         assignment = &assign;
1308 }
1309
1310 void ProgramCompiler::UnusedVariableLocator::record_assignment(VariableDeclaration &var, Node &node, bool self_ref)
1311 {
1312         VariableInfo &var_info = variables.back()[&var];
1313         if(!self_ref)
1314                 clear_assignments(var_info, true);
1315         var_info.assignments.push_back(&node);
1316         var_info.conditionally_assigned = false;
1317 }
1318
1319 void ProgramCompiler::UnusedVariableLocator::clear_assignments(VariableInfo &var_info, bool mark_unused)
1320 {
1321         if(mark_unused)
1322         {
1323                 for(vector<Node *>::iterator i=var_info.assignments.begin(); i!=var_info.assignments.end(); ++i)
1324                         unused_nodes.insert(*i);
1325         }
1326         var_info.assignments.clear();
1327 }
1328
1329 void ProgramCompiler::UnusedVariableLocator::visit(ExpressionStatement &expr)
1330 {
1331         assignment = 0;
1332         TraversingVisitor::visit(expr);
1333         if(assignment && assignment->target_declaration)
1334                 record_assignment(*assignment->target_declaration, expr, assignment->self_referencing);
1335 }
1336
1337 void ProgramCompiler::UnusedVariableLocator::visit(StructDeclaration &strct)
1338 {
1339         SetForScope<Node *> set(aggregate, &strct);
1340         unused_nodes.insert(&strct);
1341         TraversingVisitor::visit(strct);
1342 }
1343
1344 void ProgramCompiler::UnusedVariableLocator::visit(VariableDeclaration &var)
1345 {
1346         if(aggregate)
1347                 aggregates[&var] = aggregate;
1348         else
1349         {
1350                 variables.back()[&var].local = true;
1351                 if(var.init_expression)
1352                         record_assignment(var, *var.init_expression, false);
1353         }
1354         unused_nodes.erase(var.type_declaration);
1355         TraversingVisitor::visit(var);
1356 }
1357
1358 void ProgramCompiler::UnusedVariableLocator::visit(InterfaceBlock &iface)
1359 {
1360         SetForScope<Node *> set(aggregate, &iface);
1361         unused_nodes.insert(&iface);
1362         TraversingVisitor::visit(iface);
1363 }
1364
1365 void ProgramCompiler::UnusedVariableLocator::visit(FunctionDeclaration &func)
1366 {
1367         variables.push_back(BlockVariableMap());
1368
1369         {
1370                 SetForScope<bool> set(global_scope, false);
1371                 for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1372                         (*i)->visit(*this);
1373                 func.body.visit(*this);
1374         }
1375
1376         BlockVariableMap &block_variables = variables.back();
1377         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1378                 i->second.conditionally_assigned = true;
1379         for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1380                 block_variables[i->get()].referenced = true;
1381         merge_down_variables();
1382 }
1383
1384 void ProgramCompiler::UnusedVariableLocator::merge_down_variables()
1385 {
1386         BlockVariableMap &parent_variables = variables[variables.size()-2];
1387         BlockVariableMap &block_variables = variables.back();
1388         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1389         {
1390                 if(i->second.local)
1391                 {
1392                         if(!i->second.referenced)
1393                                 unused_nodes.insert(i->first);
1394                         clear_assignments(i->second, true);
1395                         continue;
1396                 }
1397
1398                 BlockVariableMap::iterator j = parent_variables.find(i->first);
1399                 if(j==parent_variables.end())
1400                         parent_variables.insert(*i);
1401                 else
1402                 {
1403                         if(i->second.referenced || !i->second.conditionally_assigned)
1404                                 clear_assignments(j->second, !i->second.referenced);
1405                         j->second.conditionally_assigned = i->second.conditionally_assigned;
1406                         j->second.referenced |= i->second.referenced;
1407                         j->second.assignments.insert(j->second.assignments.end(), i->second.assignments.begin(), i->second.assignments.end());
1408                 }
1409         }
1410         variables.pop_back();
1411 }
1412
1413 void ProgramCompiler::UnusedVariableLocator::visit(Conditional &cond)
1414 {
1415         cond.condition->visit(*this);
1416         variables.push_back(BlockVariableMap());
1417         cond.body.visit(*this);
1418
1419         BlockVariableMap if_variables;
1420         swap(variables.back(), if_variables);
1421         cond.else_body.visit(*this);
1422
1423         BlockVariableMap &else_variables = variables.back();
1424         for(BlockVariableMap::iterator i=else_variables.begin(); i!=else_variables.end(); ++i)
1425         {
1426                 BlockVariableMap::iterator j = if_variables.find(i->first);
1427                 if(j!=if_variables.end())
1428                 {
1429                         i->second.assignments.insert(i->second.assignments.end(), j->second.assignments.begin(), j->second.assignments.end());
1430                         i->second.conditionally_assigned |= j->second.conditionally_assigned;
1431                         if_variables.erase(j);
1432                 }
1433                 else
1434                         i->second.conditionally_assigned = true;
1435         }
1436
1437         for(BlockVariableMap::iterator i=if_variables.begin(); i!=if_variables.end(); ++i)
1438         {
1439                 i->second.conditionally_assigned = true;
1440                 else_variables.insert(*i);
1441         }
1442
1443         merge_down_variables();
1444 }
1445
1446 void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
1447 {
1448         variables.push_back(BlockVariableMap());
1449         TraversingVisitor::visit(iter);
1450
1451         BlockVariableMap &block_variables = variables.back();
1452         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1453                 if(!i->second.local && i->second.referenced)
1454                         i->second.assignments.clear();
1455
1456         merge_down_variables();
1457 }
1458
1459
1460 ProgramCompiler::UnusedVariableLocator::VariableInfo::VariableInfo():
1461         local(false),
1462         conditionally_assigned(false),
1463         referenced(false)
1464 { }
1465
1466
1467 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionCall &call)
1468 {
1469         TraversingVisitor::visit(call);
1470
1471         unused_nodes.erase(call.declaration);
1472         if(call.declaration && call.declaration->definition!=call.declaration)
1473                 used_definitions.insert(call.declaration->definition);
1474 }
1475
1476 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionDeclaration &func)
1477 {
1478         TraversingVisitor::visit(func);
1479
1480         if((func.name!="main" || func.body.body.empty()) && !used_definitions.count(&func))
1481                 unused_nodes.insert(&func);
1482 }
1483
1484
1485 ProgramCompiler::NodeRemover::NodeRemover(const set<Node *> &r):
1486         to_remove(r)
1487 { }
1488
1489 void ProgramCompiler::NodeRemover::visit(Block &block)
1490 {
1491         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
1492         {
1493                 (*i)->visit(*this);
1494                 if(to_remove.count(i->get()))
1495                         block.body.erase(i++);
1496                 else
1497                         ++i;
1498         }
1499 }
1500
1501 void ProgramCompiler::NodeRemover::visit(VariableDeclaration &var)
1502 {
1503         if(to_remove.count(&var))
1504         {
1505                 stage->in_variables.erase(var.name);
1506                 stage->out_variables.erase(var.name);
1507                 stage->locations.erase(var.name);
1508                 if(var.linked_declaration)
1509                         var.linked_declaration->linked_declaration = 0;
1510         }
1511         else if(var.init_expression && to_remove.count(var.init_expression.get()))
1512                 var.init_expression = 0;
1513 }
1514
1515
1516 void ProgramCompiler::PrecisionRemover::visit(Precision &)
1517 {
1518         remove_node = true;
1519 }
1520
1521 void ProgramCompiler::PrecisionRemover::visit(VariableDeclaration &var)
1522 {
1523         var.precision.clear();
1524 }
1525
1526
1527 ProgramCompiler::DefaultPrecisionGenerator::DefaultPrecisionGenerator():
1528         toplevel(true)
1529 { }
1530
1531 void ProgramCompiler::DefaultPrecisionGenerator::visit(Block &block)
1532 {
1533         if(toplevel)
1534         {
1535                 SetForScope<bool> set(toplevel, false);
1536                 BlockModifier::visit(block);
1537         }
1538         else
1539                 Visitor::visit(block);
1540 }
1541
1542 void ProgramCompiler::DefaultPrecisionGenerator::visit(Precision &prec)
1543 {
1544         have_default.insert(prec.type);
1545 }
1546
1547 void ProgramCompiler::DefaultPrecisionGenerator::visit(VariableDeclaration &var)
1548 {
1549         if(var.type_declaration)
1550                 return;
1551
1552         string type = var.type;
1553         if(!type.compare(0, 3, "vec") || !type.compare(0, 3, "mat"))
1554                 type = "float";
1555         else if(!type.compare(0, 3, "ivec") || type=="uint")
1556                 type = "int";
1557
1558         if(!have_default.count(type))
1559         {
1560                 Precision *prec = new Precision;
1561                 if(!type.compare(0, 7, "sampler"))
1562                         prec->precision = "lowp";
1563                 else if(stage->type==FRAGMENT)
1564                         prec->precision = "mediump";
1565                 else
1566                         prec->precision = "highp";
1567                 prec->type = type;
1568                 insert_nodes.push_back(prec);
1569
1570                 have_default.insert(type);
1571         }
1572 }
1573
1574
1575 ProgramCompiler::LegacyConverter::LegacyConverter():
1576         target_api(get_gl_api()),
1577         target_version(get_glsl_version()),
1578         frag_out(0)
1579 { }
1580
1581 ProgramCompiler::LegacyConverter::LegacyConverter(const Version &v):
1582         target_api(get_gl_api()),
1583         target_version(v),
1584         frag_out(0)
1585 { }
1586
1587 bool ProgramCompiler::LegacyConverter::check_version(const Version &feature_version) const
1588 {
1589         if(target_version<feature_version)
1590                 return false;
1591         else if(stage->required_version<feature_version)
1592                 stage->required_version = feature_version;
1593
1594         return true;
1595 }
1596
1597 bool ProgramCompiler::LegacyConverter::supports_unified_interface_syntax() const
1598 {
1599         if(target_api==OPENGL_ES2)
1600                 return check_version(Version(3, 0));
1601         else
1602                 return check_version(Version(1, 30));
1603 }
1604
1605 void ProgramCompiler::LegacyConverter::visit(VariableReference &var)
1606 {
1607         if(var.declaration==frag_out && !supports_unified_interface_syntax())
1608         {
1609                 var.name = "gl_FragColor";
1610                 var.declaration = 0;
1611                 type = "vec4";
1612         }
1613         else if(var.declaration)
1614                 type = var.declaration->type;
1615         else
1616                 type = string();
1617 }
1618
1619 void ProgramCompiler::LegacyConverter::visit(Assignment &assign)
1620 {
1621         TraversingVisitor::visit(assign);
1622         if(assign.target_declaration==frag_out && !supports_unified_interface_syntax())
1623                 assign.target_declaration = 0;
1624 }
1625
1626 bool ProgramCompiler::LegacyConverter::supports_unified_sampling_functions() const
1627 {
1628         if(target_api==OPENGL_ES2)
1629                 return check_version(Version(3, 0));
1630         else
1631                 return check_version(Version(1, 30));
1632 }
1633
1634 void ProgramCompiler::LegacyConverter::visit(FunctionCall &call)
1635 {
1636         if(call.name=="texture" && !call.declaration && !supports_unified_sampling_functions())
1637         {
1638                 vector<RefPtr<Expression> >::iterator i = call.arguments.begin();
1639                 if(i!=call.arguments.end())
1640                 {
1641                         (*i)->visit(*this);
1642                         if(type=="sampler1D")
1643                                 call.name = "texture1D";
1644                         else if(type=="sampler2D")
1645                                 call.name = "texture2D";
1646                         else if(type=="sampler3D")
1647                                 call.name = "texture3D";
1648                         else if(type=="sampler1DShadow")
1649                                 call.name = "shadow1D";
1650                         else if(type=="sampler2DShadow")
1651                                 call.name = "shadow2D";
1652
1653                         for(; i!=call.arguments.end(); ++i)
1654                                 (*i)->visit(*this);
1655                 }
1656         }
1657         else
1658                 TraversingVisitor::visit(call);
1659 }
1660
1661 bool ProgramCompiler::LegacyConverter::supports_interface_layouts() const
1662 {
1663         if(target_api==OPENGL_ES2)
1664                 return check_version(Version(3, 0));
1665         else
1666                 return check_version(Version(3, 30));
1667 }
1668
1669 void ProgramCompiler::LegacyConverter::visit(VariableDeclaration &var)
1670 {
1671         if(var.layout && !supports_interface_layouts())
1672         {
1673                 vector<Layout::Qualifier>::iterator i;
1674                 for(i=var.layout->qualifiers.begin(); (i!=var.layout->qualifiers.end() && i->identifier!="location"); ++i) ;
1675                 if(i!=var.layout->qualifiers.end())
1676                 {
1677                         unsigned location = lexical_cast<unsigned>(i->value);
1678                         if(stage->type==VERTEX && var.interface=="in")
1679                         {
1680                                 stage->locations[var.name] = location;
1681                                 var.layout->qualifiers.erase(i);
1682                         }
1683                         else if(stage->type==FRAGMENT && var.interface=="out")
1684                         {
1685                                 if(location!=0)
1686                                         static Require _req(EXT_gpu_shader4);
1687                                 stage->locations[var.name] = location;
1688                                 var.layout->qualifiers.erase(i);
1689                         }
1690
1691                         if(var.layout->qualifiers.empty())
1692                                 var.layout = 0;
1693                 }
1694         }
1695
1696         if((var.interface=="in" || var.interface=="out") && !supports_unified_interface_syntax())
1697         {
1698                 if(stage->type==FRAGMENT && var.interface=="out")
1699                 {
1700                         frag_out = &var;
1701                         remove_node = true;
1702                 }
1703         }
1704
1705         TraversingVisitor::visit(var);
1706 }
1707
1708 bool ProgramCompiler::LegacyConverter::supports_interface_blocks(const string &iface) const
1709 {
1710         if(target_api==OPENGL_ES2)
1711         {
1712                 if(iface=="uniform")
1713                         return check_version(Version(3, 0));
1714                 else
1715                         return check_version(Version(3, 20));
1716         }
1717         else
1718                 return check_version(Version(1, 50));
1719 }
1720
1721 void ProgramCompiler::LegacyConverter::visit(InterfaceBlock &iface)
1722 {
1723         if(!supports_interface_blocks(iface.interface))
1724                 flatten_block(iface.members);
1725 }
1726
1727 } // namespace GL
1728 } // namespace Msp