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         "#pragma MSP stage(vertex)\n"
  17         "out gl_PerVertex {\n"
  18         "  vec4 gl_Position;\n"
  19         "  float gl_ClipDistance[];\n"
  20         "};\n"
  21         "#pragma MSP stage(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 ProgramCompiler::~ProgramCompiler()
  44 {
  45         delete module;
  46 }
  47
  48 void ProgramCompiler::compile(const string &source, const string &src_name)
  49 {
  50         resources = 0;
  51         delete module;
  52         module = new Module();
  53         ProgramParser parser;
  54         imported_names.insert(src_name);
  55         append_module(parser.parse(source, src_name));
  56         process();
  57 }
  58
  59 void ProgramCompiler::compile(IO::Base &io, Resources *res, const string &src_name)
  60 {
  61         resources = res;
  62         delete module;
  63         module = new Module();
  64         ProgramParser parser;
  65         imported_names.insert(src_name);
  66         append_module(parser.parse(io, src_name));
  67         process();
  68 }
  69
  70 void ProgramCompiler::compile(IO::Base &io, const string &src_name)
  71 {
  72         compile(io, 0, src_name);
  73 }
  74
  75 void ProgramCompiler::add_shaders(Program &program)
  76 {
  77         if(!module)
  78                 throw invalid_operation("ProgramCompiler::add_shaders");
  79
  80         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
  81         {
  82                 if(i->type==VERTEX)
  83                 {
  84                         program.attach_shader_owned(new VertexShader(apply<Formatter>(*i)));
  85                         for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
  86                                 program.bind_attribute(j->second, j->first);
  87                 }
  88                 else if(i->type==GEOMETRY)
  89                         program.attach_shader_owned(new GeometryShader(apply<Formatter>(*i)));
  90                 else if(i->type==FRAGMENT)
  91                 {
  92                         program.attach_shader_owned(new FragmentShader(apply<Formatter>(*i)));
  93                         if(EXT_gpu_shader4)
  94                         {
  95                                 for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
  96                                         program.bind_fragment_data(j->second, j->first);
  97                         }
  98                 }
  99         }
 100 }
 101
 102 Module *ProgramCompiler::create_builtins_module()
 103 {
 104         ProgramParser parser;
 105         Module *module = new Module(parser.parse(builtins_src, "<builtin>"));
 106         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 107         {
 108                 VariableResolver resolver;
 109                 i->content.visit(resolver);
 110                 for(map<string, VariableDeclaration *>::iterator j=i->content.variables.begin(); j!=i->content.variables.end(); ++j)
 111                         j->second->linked_declaration = j->second;
 112         }
 113         return module;
 114 }
 115
 116 Module &ProgramCompiler::get_builtins_module()
 117 {
 118         static RefPtr<Module> builtins_module = create_builtins_module();
 119         return *builtins_module;
 120 }
 121
 122 Stage *ProgramCompiler::get_builtins(StageType type)
 123 {
 124         Module &module = get_builtins_module();
 125         for(list<Stage>::iterator i=module.stages.begin(); i!=module.stages.end(); ++i)
 126                 if(i->type==type)
 127                         return &*i;
 128         return 0;
 129 }
 130
 131 void ProgramCompiler::append_module(ProgramSyntax::Module &mod)
 132 {
 133         vector<Import *> imports = apply<NodeGatherer<Import> >(mod.shared);
 134         for(vector<Import *>::iterator i=imports.begin(); i!=imports.end(); ++i)
 135                 import((*i)->module);
 136         apply<NodeRemover>(mod.shared, set<Node *>(imports.begin(), imports.end()));
 137
 138         append_stage(mod.shared);
 139         for(list<Stage>::iterator i=mod.stages.begin(); i!=mod.stages.end(); ++i)
 140                 append_stage(*i);
 141 }
 142
 143 void ProgramCompiler::append_stage(Stage &stage)
 144 {
 145         Stage *target = 0;
 146         if(stage.type==SHARED)
 147                 target = &module->shared;
 148         else
 149         {
 150                 list<Stage>::iterator i;
 151                 for(i=module->stages.begin(); (i!=module->stages.end() && i->type<stage.type); ++i) ;
 152                 if(i==module->stages.end() || i->type>stage.type)
 153                 {
 154                         list<Stage>::iterator j = module->stages.insert(i, stage.type);
 155                         if(i!=module->stages.end())
 156                                 i->previous = &*j;
 157                         i = j;
 158                         if(i!=module->stages.begin())
 159                                 i->previous = &*--j;
 160                 }
 161
 162                 target = &*i;
 163         }
 164
 165         for(NodeList<Node>::iterator i=stage.content.body.begin(); i!=stage.content.body.end(); ++i)
 166                 target->content.body.push_back(*i);
 167         apply<DeclarationCombiner>(*target);
 168 }
 169
 170 void ProgramCompiler::process()
 171 {
 172         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 173                 generate(*i);
 174         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); )
 175         {
 176                 if(optimize(*i))
 177                         i = module->stages.begin();
 178                 else
 179                         ++i;
 180         }
 181         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 182                 finalize(*i);
 183 }
 184
 185 void ProgramCompiler::import(const string &name)
 186 {
 187         string fn = name+".glsl";
 188         if(imported_names.count(fn))
 189                 return;
 190         imported_names.insert(fn);
 191
 192         RefPtr<IO::Seekable> io = (resources ? resources->open_raw(fn) : Resources::get_builtins().open(fn));
 193         if(!io)
 194                 throw runtime_error(format("module %s not found", name));
 195         ProgramParser import_parser;
 196         append_module(import_parser.parse(*io, fn));
 197 }
 198
 199 void ProgramCompiler::generate(Stage &stage)
 200 {
 201         inject_block(stage.content, module->shared.content);
 202
 203         apply<DeclarationReorderer>(stage);
 204         apply<FunctionResolver>(stage);
 205         apply<VariableResolver>(stage);
 206         apply<InterfaceGenerator>(stage);
 207         apply<VariableResolver>(stage);
 208         apply<DeclarationReorderer>(stage);
 209         apply<FunctionResolver>(stage);
 210         apply<LegacyConverter>(stage);
 211 }
 212
 213 bool ProgramCompiler::optimize(Stage &stage)
 214 {
 215         apply<ConstantConditionEliminator>(stage);
 216
 217         set<FunctionDeclaration *> inlineable = apply<InlineableFunctionLocator>(stage);
 218         apply<FunctionInliner>(stage, inlineable);
 219
 220         set<Node *> unused = apply<UnusedVariableLocator>(stage);
 221         set<Node *> unused2 = apply<UnusedFunctionLocator>(stage);
 222         unused.insert(unused2.begin(), unused2.end());
 223         apply<NodeRemover>(stage, unused);
 224
 225         return !unused.empty();
 226 }
 227
 228 void ProgramCompiler::finalize(Stage &stage)
 229 {
 230         if(get_gl_api()==OPENGL_ES2)
 231                 apply<DefaultPrecisionGenerator>(stage);
 232         else
 233                 apply<PrecisionRemover>(stage);
 234 }
 235
 236 void ProgramCompiler::inject_block(Block &target, const Block &source)
 237 {
 238         list<RefPtr<Node> >::iterator insert_point = target.body.begin();
 239         for(list<RefPtr<Node> >::const_iterator i=source.body.begin(); i!=source.body.end(); ++i)
 240                 target.body.insert(insert_point, (*i)->clone());
 241 }
 242
 243 template<typename T>
 244 typename T::ResultType ProgramCompiler::apply(Stage &stage)
 245 {
 246         T visitor;
 247         visitor.apply(stage);
 248         return visitor.get_result();
 249 }
 250
 251 template<typename T, typename A>
 252 typename T::ResultType ProgramCompiler::apply(Stage &stage, const A &arg)
 253 {
 254         T visitor(arg);
 255         visitor.apply(stage);
 256         return visitor.get_result();
 257 }
 258
 259
 260 ProgramCompiler::Visitor::Visitor():
 261         stage(0)
 262 { }
 263
 264 void ProgramCompiler::Visitor::apply(Stage &s)
 265 {
 266         SetForScope<Stage *> set(stage, &s);
 267         stage->content.visit(*this);
 268 }
 269
 270
 271 ProgramCompiler::BlockModifier::BlockModifier():
 272         remove_node(false)
 273 { }
 274
 275 void ProgramCompiler::BlockModifier::flatten_block(Block &block)
 276 {
 277         insert_nodes.insert(insert_nodes.end(), block.body.begin(), block.body.end());
 278         remove_node = true;
 279 }
 280
 281 void ProgramCompiler::BlockModifier::apply_and_increment(Block &block, list<RefPtr<Node> >::iterator &i)
 282 {
 283         block.body.insert(i, insert_nodes.begin(), insert_nodes.end());
 284         insert_nodes.clear();
 285
 286         if(remove_node)
 287                 block.body.erase(i++);
 288         else
 289                 ++i;
 290         remove_node = false;
 291 }
 292
 293 void ProgramCompiler::BlockModifier::visit(Block &block)
 294 {
 295         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 296         {
 297                 (*i)->visit(*this);
 298                 apply_and_increment(block, i);
 299         }
 300 }
 301
 302
 303 ProgramCompiler::Formatter::Formatter():
 304         indent(0),
 305         parameter_list(false),
 306         else_if(0)
 307 { }
 308
 309 void ProgramCompiler::Formatter::apply(ProgramSyntax::Stage &s)
 310 {
 311         GLApi api = get_gl_api();
 312         const Version &ver = s.required_version;
 313
 314         if(ver)
 315         {
 316                 formatted += format("#version %d%02d", ver.major, ver.minor);
 317                 if(api==OPENGL_ES2 && ver>=Version(3, 0))
 318                         formatted += " es";
 319                 formatted += '\n';
 320         }
 321
 322         Visitor::apply(s);
 323 }
 324
 325 void ProgramCompiler::Formatter::visit(Literal &literal)
 326 {
 327         formatted += literal.token;
 328 }
 329
 330 void ProgramCompiler::Formatter::visit(ParenthesizedExpression &parexpr)
 331 {
 332         formatted += '(';
 333         parexpr.expression->visit(*this);
 334         formatted += ')';
 335 }
 336
 337 void ProgramCompiler::Formatter::visit(VariableReference &var)
 338 {
 339         formatted += var.name;
 340 }
 341
 342 void ProgramCompiler::Formatter::visit(MemberAccess &memacc)
 343 {
 344         memacc.left->visit(*this);
 345         formatted += format(".%s", memacc.member);
 346 }
 347
 348 void ProgramCompiler::Formatter::visit(UnaryExpression &unary)
 349 {
 350         if(unary.prefix)
 351                 formatted += unary.oper;
 352         unary.expression->visit(*this);
 353         if(!unary.prefix)
 354                 formatted += unary.oper;
 355 }
 356
 357 void ProgramCompiler::Formatter::visit(BinaryExpression &binary)
 358 {
 359         binary.left->visit(*this);
 360         formatted += binary.oper;
 361         binary.right->visit(*this);
 362         formatted += binary.after;
 363 }
 364
 365 void ProgramCompiler::Formatter::visit(Assignment &assign)
 366 {
 367         assign.left->visit(*this);
 368         formatted += format(" %s ", assign.oper);
 369         assign.right->visit(*this);
 370 }
 371
 372 void ProgramCompiler::Formatter::visit(FunctionCall &call)
 373 {
 374         formatted += format("%s(", call.name);
 375         for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
 376         {
 377                 if(i!=call.arguments.begin())
 378                         formatted += ", ";
 379                 (*i)->visit(*this);
 380         }
 381         formatted += ')';
 382 }
 383
 384 void ProgramCompiler::Formatter::visit(ExpressionStatement &expr)
 385 {
 386         expr.expression->visit(*this);
 387         formatted += ';';
 388 }
 389
 390 void ProgramCompiler::Formatter::visit(Block &block)
 391 {
 392         if(else_if)
 393                 --else_if;
 394
 395         unsigned brace_indent = indent;
 396         bool use_braces = (block.use_braces || (indent && block.body.size()!=1));
 397         if(use_braces)
 398                 formatted += format("%s{\n", string(brace_indent*2, ' '));
 399
 400         SetForScope<unsigned> set(indent, indent+(indent>0 || use_braces));
 401         string spaces(indent*2, ' ');
 402         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 403         {
 404                 if(i!=block.body.begin())
 405                         formatted += '\n';
 406                 formatted += spaces;
 407                 (*i)->visit(*this);
 408                 else_if = 0;
 409         }
 410
 411         if(use_braces)
 412                 formatted += format("\n%s}", string(brace_indent*2, ' '));
 413 }
 414
 415 void ProgramCompiler::Formatter::visit(Import &import)
 416 {
 417         formatted += format("import %s;", import.module);
 418 }
 419
 420 void ProgramCompiler::Formatter::visit(Precision &prec)
 421 {
 422         formatted += format("precision %s %s;", prec.precision, prec.type);
 423 }
 424
 425 void ProgramCompiler::Formatter::visit(Layout &layout)
 426 {
 427         formatted += "layout(";
 428         for(vector<Layout::Qualifier>::const_iterator i=layout.qualifiers.begin(); i!=layout.qualifiers.end(); ++i)
 429         {
 430                 if(i!=layout.qualifiers.begin())
 431                         formatted += ", ";
 432                 formatted += i->identifier;
 433                 if(!i->value.empty())
 434                         formatted += format("=%s", i->value);
 435         }
 436         formatted += ')';
 437 }
 438
 439 void ProgramCompiler::Formatter::visit(InterfaceLayout &layout)
 440 {
 441         layout.layout.visit(*this);
 442         formatted += format(" %s;", layout.interface);
 443 }
 444
 445 void ProgramCompiler::Formatter::visit(StructDeclaration &strct)
 446 {
 447         formatted += format("struct %s\n", strct.name);
 448         strct.members.visit(*this);
 449         formatted += ';';
 450 }
 451
 452 void ProgramCompiler::Formatter::visit(VariableDeclaration &var)
 453 {
 454         if(var.layout)
 455         {
 456                 var.layout->visit(*this);
 457                 formatted += ' ';
 458         }
 459         if(var.constant)
 460                 formatted += "const ";
 461         if(!var.interpolation.empty())
 462                 formatted += format("%s ", var.interpolation);
 463         if(!var.sampling.empty())
 464                 formatted += format("%s ", var.sampling);
 465         if(!var.interface.empty() && var.interface!=block_interface)
 466         {
 467                 string interface = var.interface;
 468                 if(stage->required_version<Version(1, 30))
 469                 {
 470                         if(stage->type==VERTEX && var.interface=="in")
 471                                 interface = "attribute";
 472                         else if((stage->type==VERTEX && var.interface=="out") || (stage->type==FRAGMENT && var.interface=="in"))
 473                                 interface = "varying";
 474                 }
 475                 formatted += format("%s ", interface);
 476         }
 477         if(!var.precision.empty())
 478                 formatted += format("%s ", var.precision);
 479         formatted += format("%s %s", var.type, var.name);
 480         if(var.array)
 481         {
 482                 formatted += '[';
 483                 if(var.array_size)
 484                         var.array_size->visit(*this);
 485                 formatted += ']';
 486         }
 487         if(var.init_expression)
 488         {
 489                 formatted += " = ";
 490                 var.init_expression->visit(*this);
 491         }
 492         if(!parameter_list)
 493                 formatted += ';';
 494 }
 495
 496 void ProgramCompiler::Formatter::visit(InterfaceBlock &iface)
 497 {
 498         SetForScope<string> set(block_interface, iface.interface);
 499         formatted += format("%s %s\n", iface.interface, iface.name);
 500         iface.members.visit(*this);
 501         formatted += ';';
 502 }
 503
 504 void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 505 {
 506         formatted += format("%s %s(", func.return_type, func.name);
 507         for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 508         {
 509                 if(i!=func.parameters.begin())
 510                         formatted += ", ";
 511                 SetFlag set(parameter_list);
 512                 (*i)->visit(*this);
 513         }
 514         formatted += ')';
 515         if(func.definition==&func)
 516         {
 517                 formatted += '\n';
 518                 func.body.visit(*this);
 519         }
 520         else
 521                 formatted += ';';
 522 }
 523
 524 void ProgramCompiler::Formatter::visit(Conditional &cond)
 525 {
 526         if(else_if)
 527                 formatted.replace(formatted.rfind('\n'), string::npos, 1, ' ');
 528
 529         indent -= else_if;
 530
 531         formatted += "if(";
 532         cond.condition->visit(*this);
 533         formatted += ")\n";
 534
 535         cond.body.visit(*this);
 536         if(!cond.else_body.body.empty())
 537         {
 538                 formatted += format("\n%selse\n", string(indent*2, ' '));
 539                 SetForScope<unsigned> set(else_if, 2);
 540                 cond.else_body.visit(*this);
 541         }
 542 }
 543
 544 void ProgramCompiler::Formatter::visit(Iteration &iter)
 545 {
 546         if(!iter.init_statement && iter.condition && !iter.loop_expression)
 547         {
 548                 formatted += "while(";
 549                 iter.condition->visit(*this);
 550                 formatted += ')';
 551         }
 552         else
 553         {
 554                 formatted += "for(";
 555                 if(iter.init_statement)
 556                         iter.init_statement->visit(*this);
 557                 else
 558                         formatted += ';';
 559                 if(iter.condition)
 560                 {
 561                         formatted += ' ';
 562                         iter.condition->visit(*this);
 563                 }
 564                 formatted += ';';
 565                 if(iter.loop_expression)
 566                 {
 567                         formatted += ' ';
 568                         iter.loop_expression->visit(*this);
 569                 }
 570                 formatted += ')';
 571         }
 572
 573         if(iter.body.body.empty())
 574                 formatted += " { }";
 575         else
 576         {
 577                 formatted += '\n';
 578                 iter.body.visit(*this);
 579         }
 580 }
 581
 582 void ProgramCompiler::Formatter::visit(Return &ret)
 583 {
 584         formatted += "return";
 585         if(ret.expression)
 586         {
 587                 formatted += ' ';
 588                 ret.expression->visit(*this);
 589         }
 590         formatted += ';';
 591 }
 592
 593 void ProgramCompiler::Formatter::visit(Jump &jump)
 594 {
 595         formatted += jump.keyword;
 596         formatted += ';';
 597 }
 598
 599
 600 ProgramCompiler::DeclarationCombiner::DeclarationCombiner():
 601         toplevel(true)
 602 { }
 603
 604 void ProgramCompiler::DeclarationCombiner::visit(Block &block)
 605 {
 606         if(!toplevel)
 607                 return;
 608
 609         SetForScope<bool> set(toplevel, false);
 610         BlockModifier::visit(block);
 611 }
 612
 613 void ProgramCompiler::DeclarationCombiner::visit(FunctionDeclaration &func)
 614 {
 615         vector<FunctionDeclaration *> &decls = functions[func.name];
 616         if(func.definition)
 617         {
 618                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 619                 {
 620                         (*i)->definition = func.definition;
 621                         (*i)->body.body.clear();
 622                 }
 623         }
 624         decls.push_back(&func);
 625 }
 626
 627 void ProgramCompiler::DeclarationCombiner::visit(VariableDeclaration &var)
 628 {
 629         VariableDeclaration *&ptr = variables[var.name];
 630         if(ptr)
 631         {
 632                 ptr->type = var.type;
 633                 if(var.init_expression)
 634                         ptr->init_expression = var.init_expression;
 635                 remove_node = true;
 636         }
 637         else
 638                 ptr = &var;
 639 }
 640
 641
 642 ProgramCompiler::VariableResolver::VariableResolver():
 643         anonymous(false),
 644         record_target(false),
 645         assignment_target(0),
 646         self_referencing(false)
 647 { }
 648
 649 void ProgramCompiler::VariableResolver::apply(Stage &s)
 650 {
 651         SetForScope<Stage *> set(stage, &s);
 652         Stage *builtins = get_builtins(stage->type);
 653         if(builtins)
 654                 blocks.push_back(&builtins->content);
 655         stage->content.visit(*this);
 656         if(builtins)
 657                 blocks.pop_back();
 658 }
 659
 660 void ProgramCompiler::VariableResolver::visit(Block &block)
 661 {
 662         blocks.push_back(&block);
 663         block.variables.clear();
 664         TraversingVisitor::visit(block);
 665         blocks.pop_back();
 666 }
 667
 668 void ProgramCompiler::VariableResolver::visit(VariableReference &var)
 669 {
 670         var.declaration = 0;
 671         type = 0;
 672         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 673         {
 674                 --i;
 675                 map<string, VariableDeclaration *>::iterator j = (*i)->variables.find(var.name);
 676                 if(j!=(*i)->variables.end())
 677                 {
 678                         var.declaration = j->second;
 679                         type = j->second->type_declaration;
 680                         break;
 681                 }
 682         }
 683
 684         if(record_target)
 685         {
 686                 if(assignment_target)
 687                 {
 688                         record_target = false;
 689                         assignment_target = 0;
 690                 }
 691                 else
 692                         assignment_target = var.declaration;
 693         }
 694         else if(var.declaration && var.declaration==assignment_target)
 695                 self_referencing = true;
 696 }
 697
 698 void ProgramCompiler::VariableResolver::visit(MemberAccess &memacc)
 699 {
 700         type = 0;
 701         TraversingVisitor::visit(memacc);
 702         memacc.declaration = 0;
 703         if(type)
 704         {
 705                 map<string, VariableDeclaration *>::iterator i = type->members.variables.find(memacc.member);
 706                 if(i!=type->members.variables.end())
 707                 {
 708                         memacc.declaration = i->second;
 709                         type = i->second->type_declaration;
 710                 }
 711                 else
 712                         type = 0;
 713         }
 714 }
 715
 716 void ProgramCompiler::VariableResolver::visit(BinaryExpression &binary)
 717 {
 718         if(binary.oper=="[")
 719         {
 720                 {
 721                         SetForScope<bool> set(record_target, false);
 722                         binary.right->visit(*this);
 723                 }
 724                 type = 0;
 725                 binary.left->visit(*this);
 726         }
 727         else
 728         {
 729                 TraversingVisitor::visit(binary);
 730                 type = 0;
 731         }
 732 }
 733
 734 void ProgramCompiler::VariableResolver::visit(Assignment &assign)
 735 {
 736         {
 737                 SetFlag set(record_target);
 738                 assignment_target = 0;
 739                 assign.left->visit(*this);
 740         }
 741
 742         self_referencing = false;
 743         assign.right->visit(*this);
 744
 745         assign.self_referencing = (self_referencing || assign.oper!="=");
 746         assign.target_declaration = assignment_target;
 747 }
 748
 749 void ProgramCompiler::VariableResolver::visit(StructDeclaration &strct)
 750 {
 751         TraversingVisitor::visit(strct);
 752         blocks.back()->types[strct.name] = &strct;
 753 }
 754
 755 void ProgramCompiler::VariableResolver::visit(VariableDeclaration &var)
 756 {
 757         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 758         {
 759                 --i;
 760                 map<string, StructDeclaration *>::iterator j = (*i)->types.find(var.type);
 761                 if(j!=(*i)->types.end())
 762                         var.type_declaration = j->second;
 763         }
 764
 765         if(!block_interface.empty() && var.interface.empty())
 766                 var.interface = block_interface;
 767
 768         TraversingVisitor::visit(var);
 769         blocks.back()->variables[var.name] = &var;
 770         if(anonymous && blocks.size()>1)
 771                 blocks[blocks.size()-2]->variables[var.name] = &var;
 772 }
 773
 774 void ProgramCompiler::VariableResolver::visit(InterfaceBlock &iface)
 775 {
 776         SetFlag set(anonymous);
 777         SetForScope<string> set2(block_interface, iface.interface);
 778         TraversingVisitor::visit(iface);
 779 }
 780
 781
 782 void ProgramCompiler::FunctionResolver::visit(FunctionCall &call)
 783 {
 784         map<string, vector<FunctionDeclaration *> >::iterator i = functions.find(call.name);
 785         if(i!=functions.end())
 786                 call.declaration = i->second.back();
 787
 788         TraversingVisitor::visit(call);
 789 }
 790
 791 void ProgramCompiler::FunctionResolver::visit(FunctionDeclaration &func)
 792 {
 793         vector<FunctionDeclaration *> &decls = functions[func.name];
 794         if(func.definition)
 795         {
 796                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 797                         (*i)->definition = func.definition;
 798                 decls.clear();
 799                 decls.push_back(&func);
 800         }
 801         else if(!decls.empty() && decls.back()->definition)
 802                 func.definition = decls.back()->definition;
 803         else
 804                 decls.push_back(&func);
 805
 806         TraversingVisitor::visit(func);
 807 }
 808
 809
 810 ProgramCompiler::InterfaceGenerator::InterfaceGenerator():
 811         scope_level(0)
 812 { }
 813
 814 string ProgramCompiler::InterfaceGenerator::get_out_prefix(StageType type)
 815 {
 816         if(type==VERTEX)
 817                 return "_vs_out_";
 818         else if(type==GEOMETRY)
 819                 return "_gs_out_";
 820         else
 821                 return string();
 822 }
 823
 824 void ProgramCompiler::InterfaceGenerator::apply(Stage &s)
 825 {
 826         SetForScope<Stage *> set(stage, &s);
 827         if(stage->previous)
 828                 in_prefix = get_out_prefix(stage->previous->type);
 829         out_prefix = get_out_prefix(stage->type);
 830         stage->content.visit(*this);
 831 }
 832
 833 void ProgramCompiler::InterfaceGenerator::visit(Block &block)
 834 {
 835         SetForScope<unsigned> set(scope_level, scope_level+1);
 836         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 837         {
 838                 (*i)->visit(*this);
 839
 840                 if(scope_level==1)
 841                 {
 842                         for(map<string, RefPtr<VariableDeclaration> >::iterator j=iface_declarations.begin(); j!=iface_declarations.end(); ++j)
 843                         {
 844                                 list<RefPtr<Node> >::iterator k = block.body.insert(i, j->second);
 845                                 (*k)->visit(*this);
 846                         }
 847                         iface_declarations.clear();
 848                 }
 849
 850                 apply_and_increment(block, i);
 851         }
 852 }
 853
 854 string ProgramCompiler::InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
 855 {
 856         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
 857         return prefix+name.substr(offset);
 858 }
 859
 860 bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
 861 {
 862         const map<string, VariableDeclaration *> &stage_vars = (iface=="in" ? stage->in_variables : stage->out_variables);
 863         if(stage_vars.count(name) || iface_declarations.count(name))
 864                 return false;
 865
 866         VariableDeclaration* iface_var = new VariableDeclaration;
 867         iface_var->sampling = var.sampling;
 868         iface_var->interface = iface;
 869         iface_var->type = var.type;
 870         iface_var->type_declaration = var.type_declaration;
 871         iface_var->name = name;
 872         if(stage->type==GEOMETRY)
 873                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
 874         else
 875                 iface_var->array = var.array;
 876         if(iface_var->array)
 877                 iface_var->array_size = var.array_size;
 878         if(iface=="in")
 879                 iface_var->linked_declaration = &var;
 880         iface_declarations[name] = iface_var;
 881
 882         return true;
 883 }
 884
 885 void ProgramCompiler::InterfaceGenerator::insert_assignment(const string &left, ProgramSyntax::Expression *right)
 886 {
 887         Assignment *assign = new Assignment;
 888         VariableReference *ref = new VariableReference;
 889         ref->name = left;
 890         assign->left = ref;
 891         assign->oper = "=";
 892         assign->right = right;
 893
 894         ExpressionStatement *stmt = new ExpressionStatement;
 895         stmt->expression = assign;
 896         stmt->visit(*this);
 897         insert_nodes.push_back(stmt);
 898 }
 899
 900 void ProgramCompiler::InterfaceGenerator::visit(VariableReference &var)
 901 {
 902         if(var.declaration || !stage->previous)
 903                 return;
 904         if(iface_declarations.count(var.name))
 905                 return;
 906
 907         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 908         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
 909         if(i==prev_out.end())
 910                 i = prev_out.find(in_prefix+var.name);
 911         if(i!=prev_out.end())
 912         {
 913                 generate_interface(*i->second, "in", i->second->name);
 914                 var.name = i->second->name;
 915         }
 916 }
 917
 918 void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &var)
 919 {
 920         if(var.interface=="out")
 921         {
 922                 if(scope_level==1)
 923                         stage->out_variables[var.name] = &var;
 924                 else if(generate_interface(var, "out", change_prefix(var.name, string())))
 925                 {
 926                         remove_node = true;
 927                         if(var.init_expression)
 928                         {
 929                                 insert_assignment(var.name, var.init_expression->clone());
 930                                 return;
 931                         }
 932                 }
 933         }
 934         else if(var.interface=="in")
 935         {
 936                 stage->in_variables[var.name] = &var;
 937                 if(var.linked_declaration)
 938                         var.linked_declaration->linked_declaration = &var;
 939                 else if(stage->previous)
 940                 {
 941                         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 942                         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
 943                         if(i!=prev_out.end())
 944                         {
 945                                 var.linked_declaration = i->second;
 946                                 i->second->linked_declaration = &var;
 947                         }
 948                 }
 949         }
 950
 951         TraversingVisitor::visit(var);
 952 }
 953
 954 void ProgramCompiler::InterfaceGenerator::visit(Passthrough &pass)
 955 {
 956         vector<VariableDeclaration *> pass_vars;
 957
 958         for(map<string, VariableDeclaration *>::const_iterator i=stage->in_variables.begin(); i!=stage->in_variables.end(); ++i)
 959                 pass_vars.push_back(i->second);
 960         for(map<string, RefPtr<VariableDeclaration> >::const_iterator i=iface_declarations.begin(); i!=iface_declarations.end(); ++i)
 961                 if(i->second->interface=="in")
 962                         pass_vars.push_back(i->second.get());
 963
 964         if(stage->previous)
 965         {
 966                 const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 967                 for(map<string, VariableDeclaration *>::const_iterator i=prev_out.begin(); i!=prev_out.end(); ++i)
 968                 {
 969                         bool linked = false;
 970                         for(vector<VariableDeclaration *>::const_iterator j=pass_vars.begin(); (!linked && j!=pass_vars.end()); ++j)
 971                                 linked = ((*j)->linked_declaration==i->second);
 972
 973                         if(!linked && generate_interface(*i->second, "in", i->second->name))
 974                                 pass_vars.push_back(i->second);
 975                 }
 976         }
 977
 978         if(stage->type==GEOMETRY)
 979         {
 980                 VariableReference *ref = new VariableReference;
 981                 ref->name = "gl_in";
 982
 983                 BinaryExpression *subscript = new BinaryExpression;
 984                 subscript->left = ref;
 985                 subscript->oper = "[";
 986                 subscript->right = pass.subscript;
 987                 subscript->after = "]";
 988
 989                 MemberAccess *memacc = new MemberAccess;
 990                 memacc->left = subscript;
 991                 memacc->member = "gl_Position";
 992
 993                 insert_assignment("gl_Position", memacc);
 994         }
 995
 996         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
 997         {
 998                 string out_name = change_prefix((*i)->name, out_prefix);
 999                 generate_interface(**i, "out", out_name);
1000
1001                 VariableReference *ref = new VariableReference;
1002                 ref->name = (*i)->name;
1003                 if(pass.subscript)
1004                 {
1005                         BinaryExpression *subscript = new BinaryExpression;
1006                         subscript->left = ref;
1007                         subscript->oper = "[";
1008                         subscript->right = pass.subscript;
1009                         subscript->after = "]";
1010                         insert_assignment(out_name, subscript);
1011                 }
1012                 else
1013                         insert_assignment(out_name, ref);
1014         }
1015
1016         remove_node = true;
1017 }
1018
1019
1020 ProgramCompiler::DeclarationReorderer::DeclarationReorderer():
1021         scope_level(0),
1022         kind(NO_DECLARATION)
1023 { }
1024
1025 void ProgramCompiler::DeclarationReorderer::visit(FunctionCall &call)
1026 {
1027         FunctionDeclaration *def = call.declaration;
1028         if(def)
1029                 def = def->definition;
1030         if(def && !ordered_funcs.count(def))
1031                 needed_funcs.insert(def);
1032 }
1033
1034 void ProgramCompiler::DeclarationReorderer::visit(Block &block)
1035 {
1036         SetForScope<unsigned> set(scope_level, scope_level+1);
1037         if(scope_level>1)
1038                 return Visitor::visit(block);
1039
1040         list<RefPtr<Node> >::iterator struct_insert_point = block.body.end();
1041         list<RefPtr<Node> >::iterator variable_insert_point = block.body.end();
1042         list<RefPtr<Node> >::iterator function_insert_point = block.body.end();
1043         unsigned unordered_func_count = 0;
1044         bool ordered_any_funcs = false;
1045
1046         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
1047         {
1048                 kind = NO_DECLARATION;
1049                 (*i)->visit(*this);
1050
1051                 bool moved = false;
1052                 if(kind==STRUCT && struct_insert_point!=block.body.end())
1053                 {
1054                         block.body.insert(struct_insert_point, *i);
1055                         moved = true;
1056                 }
1057                 else if(kind>STRUCT && struct_insert_point==block.body.end())
1058                         struct_insert_point = i;
1059
1060                 if(kind==VARIABLE && variable_insert_point!=block.body.end())
1061                 {
1062                         block.body.insert(variable_insert_point, *i);
1063                         moved = true;
1064                 }
1065                 else if(kind>VARIABLE && variable_insert_point==block.body.end())
1066                         variable_insert_point = i;
1067
1068                 if(kind==FUNCTION)
1069                 {
1070                         if(function_insert_point==block.body.end())
1071                                 function_insert_point = i;
1072
1073                         if(needed_funcs.empty())
1074                         {
1075                                 ordered_funcs.insert(i->get());
1076                                 if(i!=function_insert_point)
1077                                 {
1078                                         block.body.insert(function_insert_point, *i);
1079                                         moved = true;
1080                                 }
1081                                 else
1082                                         ++function_insert_point;
1083                                 ordered_any_funcs = true;
1084                         }
1085                         else
1086                                 ++unordered_func_count;
1087                 }
1088
1089                 if(moved)
1090                 {
1091                         if(function_insert_point==i)
1092                                 ++function_insert_point;
1093                         block.body.erase(i++);
1094                 }
1095                 else
1096                         ++i;
1097
1098                 if(i==block.body.end() && unordered_func_count)
1099                 {
1100                         if(!ordered_any_funcs)
1101                                 // A subset of the remaining functions forms a recursive loop
1102                                 /* TODO pick a function and move it up, adding any necessary
1103                                 declarations */
1104                                 break;
1105
1106                         i = function_insert_point;
1107                         unordered_func_count = 0;
1108                 }
1109         }
1110 }
1111
1112 void ProgramCompiler::DeclarationReorderer::visit(ProgramSyntax::VariableDeclaration &var)
1113 {
1114         Visitor::visit(var);
1115         kind = VARIABLE;
1116 }
1117
1118 void ProgramCompiler::DeclarationReorderer::visit(FunctionDeclaration &func)
1119 {
1120         needed_funcs.clear();
1121         func.body.visit(*this);
1122         needed_funcs.erase(&func);
1123         kind = FUNCTION;
1124 }
1125
1126
1127 ProgramCompiler::InlineableFunctionLocator::InlineableFunctionLocator():
1128         in_function(0)
1129 { }
1130
1131 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionCall &call)
1132 {
1133         FunctionDeclaration *def = call.declaration;
1134         if(def && def->definition!=def)
1135                 def = def->definition;
1136
1137         if(def)
1138         {
1139                 unsigned &count = refcounts[def];
1140                 ++count;
1141                 if(count>1 || def==in_function)
1142                         inlineable.erase(def);
1143         }
1144
1145         TraversingVisitor::visit(call);
1146 }
1147
1148 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionDeclaration &func)
1149 {
1150         unsigned &count = refcounts[func.definition];
1151         if(!count && func.parameters.empty())
1152                 inlineable.insert(func.definition);
1153
1154         SetForScope<FunctionDeclaration *> set(in_function, &func);
1155         TraversingVisitor::visit(func);
1156 }
1157
1158
1159 ProgramCompiler::FunctionInliner::FunctionInliner():
1160         extract_result(0)
1161 { }
1162
1163 ProgramCompiler::FunctionInliner::FunctionInliner(const set<FunctionDeclaration *> &in):
1164         inlineable(in),
1165         extract_result(0)
1166 { }
1167
1168 void ProgramCompiler::FunctionInliner::visit_and_inline(RefPtr<Expression> &ptr)
1169 {
1170         inline_result = 0;
1171         ptr->visit(*this);
1172         if(inline_result)
1173                 ptr = inline_result;
1174 }
1175
1176 void ProgramCompiler::FunctionInliner::visit(Block &block)
1177 {
1178         if(extract_result)
1179                 --extract_result;
1180
1181         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
1182         {
1183                 (*i)->visit(*this);
1184                 if(extract_result)
1185                         --extract_result;
1186         }
1187 }
1188
1189 void ProgramCompiler::FunctionInliner::visit(UnaryExpression &unary)
1190 {
1191         visit_and_inline(unary.expression);
1192         inline_result = 0;
1193 }
1194
1195 void ProgramCompiler::FunctionInliner::visit(BinaryExpression &binary)
1196 {
1197         visit_and_inline(binary.left);
1198         visit_and_inline(binary.right);
1199         inline_result = 0;
1200 }
1201
1202 void ProgramCompiler::FunctionInliner::visit(MemberAccess &memacc)
1203 {
1204         visit_and_inline(memacc.left);
1205         inline_result = 0;
1206 }
1207
1208 void ProgramCompiler::FunctionInliner::visit(FunctionCall &call)
1209 {
1210         for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
1211                 visit_and_inline(*i);
1212
1213         FunctionDeclaration *def = call.declaration;
1214         if(def && def->definition!=def)
1215                 def = def->definition;
1216
1217         if(def && inlineable.count(def))
1218         {
1219                 extract_result = 2;
1220                 def->visit(*this);
1221         }
1222         else
1223                 inline_result = 0;
1224 }
1225
1226 void ProgramCompiler::FunctionInliner::visit(VariableDeclaration &var)
1227 {
1228         if(var.init_expression)
1229                 visit_and_inline(var.init_expression);
1230         inline_result = 0;
1231 }
1232
1233 void ProgramCompiler::FunctionInliner::visit(Return &ret)
1234 {
1235         TraversingVisitor::visit(ret);
1236
1237         if(extract_result)
1238                 inline_result = ret.expression->clone();
1239 }
1240
1241
1242 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator():
1243         variable_values(0),
1244         result(0.0f),
1245         result_valid(false)
1246 { }
1247
1248 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator(const ValueMap &v):
1249         variable_values(&v),
1250         result(0.0f),
1251         result_valid(false)
1252 { }
1253
1254 void ProgramCompiler::ExpressionEvaluator::visit(Literal &literal)
1255 {
1256         if(literal.token=="true")
1257                 result = 1.0f;
1258         else if(literal.token=="false")
1259                 result = 0.0f;
1260         else
1261                 result = lexical_cast<float>(literal.token);
1262         result_valid = true;
1263 }
1264
1265 void ProgramCompiler::ExpressionEvaluator::visit(ParenthesizedExpression &parexp)
1266 {
1267         parexp.expression->visit(*this);
1268 }
1269
1270 void ProgramCompiler::ExpressionEvaluator::visit(VariableReference &var)
1271 {
1272         if(!var.declaration)
1273                 return;
1274
1275         if(variable_values)
1276         {
1277                 ValueMap::const_iterator i = variable_values->find(var.declaration);
1278                 if(i!=variable_values->end())
1279                         i->second->visit(*this);
1280         }
1281         else if(var.declaration->init_expression)
1282                 var.declaration->init_expression->visit(*this);
1283 }
1284
1285 void ProgramCompiler::ExpressionEvaluator::visit(UnaryExpression &unary)
1286 {
1287         result_valid = false;
1288         unary.expression->visit(*this);
1289         if(!result_valid)
1290                 return;
1291
1292         if(unary.oper=="!")
1293                 result = !result;
1294         else
1295                 result_valid = false;
1296 }
1297
1298 void ProgramCompiler::ExpressionEvaluator::visit(BinaryExpression &binary)
1299 {
1300         result_valid = false;
1301         binary.left->visit(*this);
1302         if(!result_valid)
1303                 return;
1304
1305         float left_result = result;
1306         result_valid = false;
1307         binary.right->visit(*this);
1308         if(!result_valid)
1309                 return;
1310
1311         if(binary.oper=="<")
1312                 result = (left_result<result);
1313         else if(binary.oper=="<=")
1314                 result = (left_result<=result);
1315         else if(binary.oper==">")
1316                 result = (left_result>result);
1317         else if(binary.oper==">=")
1318                 result = (left_result>=result);
1319         else if(binary.oper=="==")
1320                 result = (left_result==result);
1321         else if(binary.oper=="!=")
1322                 result = (left_result!=result);
1323         else if(binary.oper=="&&")
1324                 result = (left_result && result);
1325         else if(binary.oper=="||")
1326                 result = (left_result || result);
1327         else
1328                 result_valid = false;
1329 }
1330
1331
1332 ProgramCompiler::ConstantConditionEliminator::ConstantConditionEliminator():
1333         scope_level(0),
1334         record_only(false)
1335 { }
1336
1337 void ProgramCompiler::ConstantConditionEliminator::visit(Block &block)
1338 {
1339         SetForScope<unsigned> set(scope_level, scope_level+1);
1340         BlockModifier::visit(block);
1341
1342         for(map<string, VariableDeclaration *>::const_iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
1343                 variable_values.erase(i->second);
1344 }
1345
1346 void ProgramCompiler::ConstantConditionEliminator::visit(UnaryExpression &unary)
1347 {
1348         if(VariableReference *var = dynamic_cast<VariableReference *>(unary.expression.get()))
1349                 if(unary.oper=="++" || unary.oper=="--")
1350                         variable_values.erase(var->declaration);
1351 }
1352
1353 void ProgramCompiler::ConstantConditionEliminator::visit(Assignment &assign)
1354 {
1355         variable_values.erase(assign.target_declaration);
1356 }
1357
1358 void ProgramCompiler::ConstantConditionEliminator::visit(VariableDeclaration &var)
1359 {
1360         if(var.constant || scope_level>1)
1361                 variable_values[&var] = var.init_expression.get();
1362 }
1363
1364 void ProgramCompiler::ConstantConditionEliminator::visit(Conditional &cond)
1365 {
1366         if(!record_only)
1367         {
1368                 ExpressionEvaluator eval(variable_values);
1369                 cond.condition->visit(eval);
1370                 if(eval.result_valid)
1371                 {
1372                         flatten_block(eval.result ? cond.body : cond.else_body);
1373                         return;
1374                 }
1375         }
1376
1377         TraversingVisitor::visit(cond);
1378 }
1379
1380 void ProgramCompiler::ConstantConditionEliminator::visit(Iteration &iter)
1381 {
1382         if(!record_only)
1383         {
1384                 if(iter.condition)
1385                 {
1386                         /* If the loop condition is always false on the first iteration, the
1387                         entire loop can be removed */
1388                         if(iter.init_statement)
1389                                 iter.init_statement->visit(*this);
1390                         ExpressionEvaluator eval(variable_values);
1391                         iter.condition->visit(eval);
1392                         if(eval.result_valid && !eval.result)
1393                         {
1394                                 remove_node = true;
1395                                 return;
1396                         }
1397                 }
1398
1399                 /* Record all assignments that occur inside the loop body so those
1400                 variables won't be considered as constant */
1401                 SetFlag set_record(record_only);
1402                 TraversingVisitor::visit(iter);
1403         }
1404
1405         TraversingVisitor::visit(iter);
1406
1407         if(VariableDeclaration *init_decl = dynamic_cast<VariableDeclaration *>(iter.init_statement.get()))
1408                 variable_values.erase(init_decl);
1409 }
1410
1411
1412 ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
1413         aggregate(0),
1414         assignment(0),
1415         assignment_target(false),
1416         global_scope(true)
1417 { }
1418
1419 void ProgramCompiler::UnusedVariableLocator::apply(Stage &s)
1420 {
1421         variables.push_back(BlockVariableMap());
1422         Visitor::apply(s);
1423         BlockVariableMap &global_variables = variables.back();
1424         for(BlockVariableMap::iterator i=global_variables.begin(); i!=global_variables.end(); ++i)
1425         {
1426                 if(i->first->interface=="out" && (s.type==FRAGMENT || i->first->linked_declaration || !i->first->name.compare(0, 3, "gl_")))
1427                         continue;
1428                 if(!i->second.referenced)
1429                 {
1430                         unused_nodes.insert(i->first);
1431                         clear_assignments(i->second, true);
1432                 }
1433         }
1434         variables.pop_back();
1435 }
1436
1437 void ProgramCompiler::UnusedVariableLocator::visit(VariableReference &var)
1438 {
1439         map<VariableDeclaration *, Node *>::iterator i = aggregates.find(var.declaration);
1440         if(i!=aggregates.end())
1441                 unused_nodes.erase(i->second);
1442
1443         if(var.declaration && !assignment_target)
1444         {
1445                 VariableInfo &var_info = variables.back()[var.declaration];
1446                 var_info.assignments.clear();
1447                 var_info.referenced = true;
1448         }
1449 }
1450
1451 void ProgramCompiler::UnusedVariableLocator::visit(MemberAccess &memacc)
1452 {
1453         TraversingVisitor::visit(memacc);
1454         unused_nodes.erase(memacc.declaration);
1455 }
1456
1457 void ProgramCompiler::UnusedVariableLocator::visit(BinaryExpression &binary)
1458 {
1459         if(binary.oper=="[")
1460         {
1461                 binary.left->visit(*this);
1462                 SetForScope<bool> set(assignment_target, false);
1463                 binary.right->visit(*this);
1464         }
1465         else
1466                 TraversingVisitor::visit(binary);
1467 }
1468
1469 void ProgramCompiler::UnusedVariableLocator::visit(Assignment &assign)
1470 {
1471         {
1472                 SetForScope<bool> set(assignment_target, !assign.self_referencing);
1473                 assign.left->visit(*this);
1474         }
1475         assign.right->visit(*this);
1476         assignment = &assign;
1477 }
1478
1479 void ProgramCompiler::UnusedVariableLocator::record_assignment(VariableDeclaration &var, Node &node, bool self_ref)
1480 {
1481         VariableInfo &var_info = variables.back()[&var];
1482         if(!self_ref)
1483                 clear_assignments(var_info, true);
1484         var_info.assignments.push_back(&node);
1485         var_info.conditionally_assigned = false;
1486 }
1487
1488 void ProgramCompiler::UnusedVariableLocator::clear_assignments(VariableInfo &var_info, bool mark_unused)
1489 {
1490         if(mark_unused)
1491         {
1492                 for(vector<Node *>::iterator i=var_info.assignments.begin(); i!=var_info.assignments.end(); ++i)
1493                         unused_nodes.insert(*i);
1494         }
1495         var_info.assignments.clear();
1496 }
1497
1498 void ProgramCompiler::UnusedVariableLocator::visit(ExpressionStatement &expr)
1499 {
1500         assignment = 0;
1501         TraversingVisitor::visit(expr);
1502         if(assignment && assignment->target_declaration)
1503                 record_assignment(*assignment->target_declaration, expr, assignment->self_referencing);
1504 }
1505
1506 void ProgramCompiler::UnusedVariableLocator::visit(StructDeclaration &strct)
1507 {
1508         SetForScope<Node *> set(aggregate, &strct);
1509         unused_nodes.insert(&strct);
1510         TraversingVisitor::visit(strct);
1511 }
1512
1513 void ProgramCompiler::UnusedVariableLocator::visit(VariableDeclaration &var)
1514 {
1515         if(aggregate)
1516                 aggregates[&var] = aggregate;
1517         else
1518         {
1519                 variables.back()[&var].local = true;
1520                 if(var.init_expression)
1521                         record_assignment(var, *var.init_expression, false);
1522         }
1523         unused_nodes.erase(var.type_declaration);
1524         TraversingVisitor::visit(var);
1525 }
1526
1527 void ProgramCompiler::UnusedVariableLocator::visit(InterfaceBlock &iface)
1528 {
1529         SetForScope<Node *> set(aggregate, &iface);
1530         unused_nodes.insert(&iface);
1531         TraversingVisitor::visit(iface);
1532 }
1533
1534 void ProgramCompiler::UnusedVariableLocator::visit(FunctionDeclaration &func)
1535 {
1536         variables.push_back(BlockVariableMap());
1537
1538         {
1539                 SetForScope<bool> set(global_scope, false);
1540                 for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1541                         (*i)->visit(*this);
1542                 func.body.visit(*this);
1543         }
1544
1545         BlockVariableMap &block_variables = variables.back();
1546         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1547                 i->second.conditionally_assigned = true;
1548         for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1549                 block_variables[i->get()].referenced = true;
1550         merge_down_variables();
1551 }
1552
1553 void ProgramCompiler::UnusedVariableLocator::merge_down_variables()
1554 {
1555         BlockVariableMap &parent_variables = variables[variables.size()-2];
1556         BlockVariableMap &block_variables = variables.back();
1557         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1558         {
1559                 if(i->second.local)
1560                 {
1561                         if(!i->second.referenced)
1562                                 unused_nodes.insert(i->first);
1563                         clear_assignments(i->second, true);
1564                         continue;
1565                 }
1566
1567                 BlockVariableMap::iterator j = parent_variables.find(i->first);
1568                 if(j==parent_variables.end())
1569                         parent_variables.insert(*i);
1570                 else
1571                 {
1572                         if(i->second.referenced || !i->second.conditionally_assigned)
1573                                 clear_assignments(j->second, !i->second.referenced);
1574                         j->second.conditionally_assigned = i->second.conditionally_assigned;
1575                         j->second.referenced |= i->second.referenced;
1576                         j->second.assignments.insert(j->second.assignments.end(), i->second.assignments.begin(), i->second.assignments.end());
1577                 }
1578         }
1579         variables.pop_back();
1580 }
1581
1582 void ProgramCompiler::UnusedVariableLocator::visit(Conditional &cond)
1583 {
1584         cond.condition->visit(*this);
1585         variables.push_back(BlockVariableMap());
1586         cond.body.visit(*this);
1587
1588         BlockVariableMap if_variables;
1589         swap(variables.back(), if_variables);
1590         cond.else_body.visit(*this);
1591
1592         BlockVariableMap &else_variables = variables.back();
1593         for(BlockVariableMap::iterator i=else_variables.begin(); i!=else_variables.end(); ++i)
1594         {
1595                 BlockVariableMap::iterator j = if_variables.find(i->first);
1596                 if(j!=if_variables.end())
1597                 {
1598                         i->second.assignments.insert(i->second.assignments.end(), j->second.assignments.begin(), j->second.assignments.end());
1599                         i->second.conditionally_assigned |= j->second.conditionally_assigned;
1600                         if_variables.erase(j);
1601                 }
1602                 else
1603                         i->second.conditionally_assigned = true;
1604         }
1605
1606         for(BlockVariableMap::iterator i=if_variables.begin(); i!=if_variables.end(); ++i)
1607         {
1608                 i->second.conditionally_assigned = true;
1609                 else_variables.insert(*i);
1610         }
1611
1612         merge_down_variables();
1613 }
1614
1615 void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
1616 {
1617         variables.push_back(BlockVariableMap());
1618         TraversingVisitor::visit(iter);
1619
1620         BlockVariableMap &block_variables = variables.back();
1621         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1622                 if(!i->second.local && i->second.referenced)
1623                         i->second.assignments.clear();
1624
1625         merge_down_variables();
1626 }
1627
1628
1629 ProgramCompiler::UnusedVariableLocator::VariableInfo::VariableInfo():
1630         local(false),
1631         conditionally_assigned(false),
1632         referenced(false)
1633 { }
1634
1635
1636 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionCall &call)
1637 {
1638         TraversingVisitor::visit(call);
1639
1640         unused_nodes.erase(call.declaration);
1641         if(call.declaration && call.declaration->definition!=call.declaration)
1642                 used_definitions.insert(call.declaration->definition);
1643 }
1644
1645 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionDeclaration &func)
1646 {
1647         TraversingVisitor::visit(func);
1648
1649         if((func.name!="main" || func.body.body.empty()) && !used_definitions.count(&func))
1650                 unused_nodes.insert(&func);
1651 }
1652
1653
1654 ProgramCompiler::NodeRemover::NodeRemover(const set<Node *> &r):
1655         to_remove(r)
1656 { }
1657
1658 void ProgramCompiler::NodeRemover::visit(Block &block)
1659 {
1660         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
1661         {
1662                 (*i)->visit(*this);
1663                 if(to_remove.count(i->get()))
1664                         block.body.erase(i++);
1665                 else
1666                         ++i;
1667         }
1668 }
1669
1670 void ProgramCompiler::NodeRemover::visit(VariableDeclaration &var)
1671 {
1672         if(to_remove.count(&var))
1673         {
1674                 stage->in_variables.erase(var.name);
1675                 stage->out_variables.erase(var.name);
1676                 stage->locations.erase(var.name);
1677                 if(var.linked_declaration)
1678                         var.linked_declaration->linked_declaration = 0;
1679         }
1680         else if(var.init_expression && to_remove.count(var.init_expression.get()))
1681                 var.init_expression = 0;
1682 }
1683
1684 void ProgramCompiler::NodeRemover::visit(Iteration &iter)
1685 {
1686         if(to_remove.count(iter.init_statement.get()))
1687                 iter.init_statement = 0;
1688 }
1689
1690
1691 void ProgramCompiler::PrecisionRemover::visit(Precision &)
1692 {
1693         remove_node = true;
1694 }
1695
1696 void ProgramCompiler::PrecisionRemover::visit(VariableDeclaration &var)
1697 {
1698         var.precision.clear();
1699 }
1700
1701
1702 ProgramCompiler::DefaultPrecisionGenerator::DefaultPrecisionGenerator():
1703         toplevel(true)
1704 { }
1705
1706 void ProgramCompiler::DefaultPrecisionGenerator::visit(Block &block)
1707 {
1708         if(toplevel)
1709         {
1710                 SetForScope<bool> set(toplevel, false);
1711                 BlockModifier::visit(block);
1712         }
1713         else
1714                 Visitor::visit(block);
1715 }
1716
1717 void ProgramCompiler::DefaultPrecisionGenerator::visit(Precision &prec)
1718 {
1719         have_default.insert(prec.type);
1720 }
1721
1722 void ProgramCompiler::DefaultPrecisionGenerator::visit(VariableDeclaration &var)
1723 {
1724         if(var.type_declaration)
1725                 return;
1726
1727         string type = var.type;
1728         if(!type.compare(0, 3, "vec") || !type.compare(0, 3, "mat"))
1729                 type = "float";
1730         else if(!type.compare(0, 3, "ivec") || type=="uint")
1731                 type = "int";
1732
1733         if(!have_default.count(type))
1734         {
1735                 Precision *prec = new Precision;
1736                 if(!type.compare(0, 7, "sampler"))
1737                         prec->precision = "lowp";
1738                 else if(stage->type==FRAGMENT)
1739                         prec->precision = "mediump";
1740                 else
1741                         prec->precision = "highp";
1742                 prec->type = type;
1743                 insert_nodes.push_back(prec);
1744
1745                 have_default.insert(type);
1746         }
1747 }
1748
1749
1750 ProgramCompiler::LegacyConverter::LegacyConverter():
1751         target_api(get_gl_api()),
1752         target_version(get_glsl_version()),
1753         frag_out(0)
1754 { }
1755
1756 ProgramCompiler::LegacyConverter::LegacyConverter(const Version &v):
1757         target_api(get_gl_api()),
1758         target_version(v),
1759         frag_out(0)
1760 { }
1761
1762 bool ProgramCompiler::LegacyConverter::check_version(const Version &feature_version) const
1763 {
1764         if(target_version<feature_version)
1765                 return false;
1766         else if(stage->required_version<feature_version)
1767                 stage->required_version = feature_version;
1768
1769         return true;
1770 }
1771
1772 bool ProgramCompiler::LegacyConverter::supports_unified_interface_syntax() const
1773 {
1774         if(target_api==OPENGL_ES2)
1775                 return check_version(Version(3, 0));
1776         else
1777                 return check_version(Version(1, 30));
1778 }
1779
1780 void ProgramCompiler::LegacyConverter::visit(VariableReference &var)
1781 {
1782         if(var.declaration==frag_out && !supports_unified_interface_syntax())
1783         {
1784                 var.name = "gl_FragColor";
1785                 var.declaration = 0;
1786                 type = "vec4";
1787         }
1788         else if(var.declaration)
1789                 type = var.declaration->type;
1790         else
1791                 type = string();
1792 }
1793
1794 void ProgramCompiler::LegacyConverter::visit(Assignment &assign)
1795 {
1796         TraversingVisitor::visit(assign);
1797         if(assign.target_declaration==frag_out && !supports_unified_interface_syntax())
1798                 assign.target_declaration = 0;
1799 }
1800
1801 bool ProgramCompiler::LegacyConverter::supports_unified_sampling_functions() const
1802 {
1803         if(target_api==OPENGL_ES2)
1804                 return check_version(Version(3, 0));
1805         else
1806                 return check_version(Version(1, 30));
1807 }
1808
1809 void ProgramCompiler::LegacyConverter::visit(FunctionCall &call)
1810 {
1811         if(call.name=="texture" && !call.declaration && !supports_unified_sampling_functions())
1812         {
1813                 vector<RefPtr<Expression> >::iterator i = call.arguments.begin();
1814                 if(i!=call.arguments.end())
1815                 {
1816                         (*i)->visit(*this);
1817                         if(type=="sampler1D")
1818                                 call.name = "texture1D";
1819                         else if(type=="sampler2D")
1820                                 call.name = "texture2D";
1821                         else if(type=="sampler3D")
1822                                 call.name = "texture3D";
1823                         else if(type=="sampler1DShadow")
1824                                 call.name = "shadow1D";
1825                         else if(type=="sampler2DShadow")
1826                                 call.name = "shadow2D";
1827
1828                         for(; i!=call.arguments.end(); ++i)
1829                                 (*i)->visit(*this);
1830                 }
1831         }
1832         else
1833                 TraversingVisitor::visit(call);
1834 }
1835
1836 bool ProgramCompiler::LegacyConverter::supports_interface_layouts() const
1837 {
1838         if(target_api==OPENGL_ES2)
1839                 return check_version(Version(3, 0));
1840         else
1841                 return check_version(Version(3, 30));
1842 }
1843
1844 bool ProgramCompiler::LegacyConverter::supports_centroid_sampling() const
1845 {
1846         if(target_api==OPENGL_ES2)
1847                 return check_version(Version(3, 0));
1848         else
1849                 return check_version(Version(1, 20));
1850 }
1851
1852 bool ProgramCompiler::LegacyConverter::supports_sample_sampling() const
1853 {
1854         if(target_api==OPENGL_ES2)
1855                 return check_version(Version(3, 20));
1856         else
1857                 return check_version(Version(4, 0));
1858 }
1859
1860 void ProgramCompiler::LegacyConverter::visit(VariableDeclaration &var)
1861 {
1862         if(var.layout && !supports_interface_layouts())
1863         {
1864                 vector<Layout::Qualifier>::iterator i;
1865                 for(i=var.layout->qualifiers.begin(); (i!=var.layout->qualifiers.end() && i->identifier!="location"); ++i) ;
1866                 if(i!=var.layout->qualifiers.end())
1867                 {
1868                         unsigned location = lexical_cast<unsigned>(i->value);
1869                         if(stage->type==VERTEX && var.interface=="in")
1870                         {
1871                                 stage->locations[var.name] = location;
1872                                 var.layout->qualifiers.erase(i);
1873                         }
1874                         else if(stage->type==FRAGMENT && var.interface=="out")
1875                         {
1876                                 if(location!=0)
1877                                         static Require _req(EXT_gpu_shader4);
1878                                 stage->locations[var.name] = location;
1879                                 var.layout->qualifiers.erase(i);
1880                         }
1881
1882                         if(var.layout->qualifiers.empty())
1883                                 var.layout = 0;
1884                 }
1885         }
1886
1887         if(var.sampling=="centroid")
1888         {
1889                 if(!supports_centroid_sampling())
1890                         var.sampling = string();
1891         }
1892         else if(var.sampling=="sample")
1893         {
1894                 if(!supports_sample_sampling())
1895                         var.sampling = string();
1896         }
1897
1898         if((var.interface=="in" || var.interface=="out") && !supports_unified_interface_syntax())
1899         {
1900                 if(stage->type==FRAGMENT && var.interface=="out")
1901                 {
1902                         frag_out = &var;
1903                         remove_node = true;
1904                 }
1905         }
1906
1907         TraversingVisitor::visit(var);
1908 }
1909
1910 bool ProgramCompiler::LegacyConverter::supports_interface_blocks(const string &iface) const
1911 {
1912         if(target_api==OPENGL_ES2)
1913         {
1914                 if(iface=="uniform")
1915                         return check_version(Version(3, 0));
1916                 else
1917                         return check_version(Version(3, 20));
1918         }
1919         else
1920                 return check_version(Version(1, 50));
1921 }
1922
1923 void ProgramCompiler::LegacyConverter::visit(InterfaceBlock &iface)
1924 {
1925         if(!supports_interface_blocks(iface.interface))
1926                 flatten_block(iface.members);
1927 }
1928
1929 } // namespace GL
1930 } // namespace Msp