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 // XXX For some reason global declarations are emitted for otherwise undeclared local variables
  39
  40 ProgramCompiler::ProgramCompiler():
  41         resources(0),
  42         module(0)
  43 { }
  44
  45 ProgramCompiler::~ProgramCompiler()
  46 {
  47         delete module;
  48 }
  49
  50 void ProgramCompiler::compile(const string &source, const string &src_name)
  51 {
  52         resources = 0;
  53         delete module;
  54         module = new Module();
  55         ProgramParser parser;
  56         imported_names.insert(src_name);
  57         append_module(parser.parse(source, src_name));
  58         process();
  59 }
  60
  61 void ProgramCompiler::compile(IO::Base &io, Resources *res, const string &src_name)
  62 {
  63         resources = res;
  64         delete module;
  65         module = new Module();
  66         ProgramParser parser;
  67         imported_names.insert(src_name);
  68         append_module(parser.parse(io, src_name));
  69         process();
  70 }
  71
  72 void ProgramCompiler::compile(IO::Base &io, const string &src_name)
  73 {
  74         compile(io, 0, src_name);
  75 }
  76
  77 void ProgramCompiler::add_shaders(Program &program)
  78 {
  79         if(!module)
  80                 throw invalid_operation("ProgramCompiler::add_shaders");
  81
  82         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
  83         {
  84                 if(i->type==VERTEX)
  85                 {
  86                         program.attach_shader_owned(new VertexShader(apply<Formatter>(*i)));
  87                         for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
  88                                 program.bind_attribute(j->second, j->first);
  89                 }
  90                 else if(i->type==GEOMETRY)
  91                         program.attach_shader_owned(new GeometryShader(apply<Formatter>(*i)));
  92                 else if(i->type==FRAGMENT)
  93                 {
  94                         program.attach_shader_owned(new FragmentShader(apply<Formatter>(*i)));
  95                         if(EXT_gpu_shader4)
  96                         {
  97                                 for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
  98                                         program.bind_fragment_data(j->second, j->first);
  99                         }
 100                 }
 101         }
 102 }
 103
 104 Module *ProgramCompiler::create_builtins_module()
 105 {
 106         ProgramParser parser;
 107         Module *module = new Module(parser.parse(builtins_src, "<builtin>"));
 108         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 109         {
 110                 VariableResolver resolver;
 111                 i->content.visit(resolver);
 112                 for(map<string, VariableDeclaration *>::iterator j=i->content.variables.begin(); j!=i->content.variables.end(); ++j)
 113                         j->second->linked_declaration = j->second;
 114         }
 115         return module;
 116 }
 117
 118 Module &ProgramCompiler::get_builtins_module()
 119 {
 120         static RefPtr<Module> builtins_module = create_builtins_module();
 121         return *builtins_module;
 122 }
 123
 124 Stage *ProgramCompiler::get_builtins(StageType type)
 125 {
 126         Module &module = get_builtins_module();
 127         for(list<Stage>::iterator i=module.stages.begin(); i!=module.stages.end(); ++i)
 128                 if(i->type==type)
 129                         return &*i;
 130         return 0;
 131 }
 132
 133 void ProgramCompiler::append_module(ProgramSyntax::Module &mod)
 134 {
 135         vector<Import *> imports = apply<NodeGatherer<Import> >(mod.shared);
 136         for(vector<Import *>::iterator i=imports.begin(); i!=imports.end(); ++i)
 137                 import((*i)->module);
 138         apply<NodeRemover>(mod.shared, set<Node *>(imports.begin(), imports.end()));
 139
 140         append_stage(mod.shared);
 141         for(list<Stage>::iterator i=mod.stages.begin(); i!=mod.stages.end(); ++i)
 142                 append_stage(*i);
 143 }
 144
 145 void ProgramCompiler::append_stage(Stage &stage)
 146 {
 147         Stage *target = 0;
 148         if(stage.type==SHARED)
 149                 target = &module->shared;
 150         else
 151         {
 152                 list<Stage>::iterator i;
 153                 for(i=module->stages.begin(); (i!=module->stages.end() && i->type<stage.type); ++i) ;
 154                 if(i==module->stages.end() || i->type>stage.type)
 155                 {
 156                         list<Stage>::iterator j = module->stages.insert(i, stage.type);
 157                         if(i!=module->stages.end())
 158                                 i->previous = &*j;
 159                         i = j;
 160                         if(i!=module->stages.begin())
 161                                 i->previous = &*--j;
 162                 }
 163
 164                 target = &*i;
 165         }
 166
 167         for(NodeList<Node>::iterator i=stage.content.body.begin(); i!=stage.content.body.end(); ++i)
 168                 target->content.body.push_back(*i);
 169         apply<DeclarationCombiner>(*target);
 170 }
 171
 172 void ProgramCompiler::process()
 173 {
 174         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 175                 generate(*i);
 176         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); )
 177         {
 178                 if(optimize(*i))
 179                         i = module->stages.begin();
 180                 else
 181                         ++i;
 182         }
 183         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 184                 finalize(*i);
 185 }
 186
 187 void ProgramCompiler::import(const string &name)
 188 {
 189         string fn = name+".glsl";
 190         if(imported_names.count(fn))
 191                 return;
 192         imported_names.insert(fn);
 193
 194         RefPtr<IO::Seekable> io = (resources ? resources->open_raw(fn) : Resources::get_builtins().open(fn));
 195         if(!io)
 196                 throw runtime_error(format("module %s not found", name));
 197         ProgramParser import_parser;
 198         append_module(import_parser.parse(*io, fn));
 199 }
 200
 201 void ProgramCompiler::generate(Stage &stage)
 202 {
 203         inject_block(stage.content, module->shared.content);
 204
 205         apply<DeclarationReorderer>(stage);
 206         apply<FunctionResolver>(stage);
 207         apply<VariableResolver>(stage);
 208         apply<InterfaceGenerator>(stage);
 209         apply<VariableResolver>(stage);
 210         apply<DeclarationReorderer>(stage);
 211         apply<FunctionResolver>(stage);
 212         apply<LegacyConverter>(stage);
 213 }
 214
 215 bool ProgramCompiler::optimize(Stage &stage)
 216 {
 217         apply<ConstantConditionEliminator>(stage);
 218
 219         set<FunctionDeclaration *> inlineable = apply<InlineableFunctionLocator>(stage);
 220         apply<FunctionInliner>(stage, inlineable);
 221
 222         set<Node *> unused = apply<UnusedVariableLocator>(stage);
 223         set<Node *> unused2 = apply<UnusedFunctionLocator>(stage);
 224         unused.insert(unused2.begin(), unused2.end());
 225         apply<NodeRemover>(stage, unused);
 226
 227         return !unused.empty();
 228 }
 229
 230 void ProgramCompiler::finalize(Stage &stage)
 231 {
 232         if(get_gl_api()==OPENGL_ES2)
 233                 apply<DefaultPrecisionGenerator>(stage);
 234         else
 235                 apply<PrecisionRemover>(stage);
 236 }
 237
 238 void ProgramCompiler::inject_block(Block &target, const Block &source)
 239 {
 240         list<RefPtr<Node> >::iterator insert_point = target.body.begin();
 241         for(list<RefPtr<Node> >::const_iterator i=source.body.begin(); i!=source.body.end(); ++i)
 242                 target.body.insert(insert_point, (*i)->clone());
 243 }
 244
 245 template<typename T>
 246 typename T::ResultType ProgramCompiler::apply(Stage &stage)
 247 {
 248         T visitor;
 249         visitor.apply(stage);
 250         return visitor.get_result();
 251 }
 252
 253 template<typename T, typename A>
 254 typename T::ResultType ProgramCompiler::apply(Stage &stage, const A &arg)
 255 {
 256         T visitor(arg);
 257         visitor.apply(stage);
 258         return visitor.get_result();
 259 }
 260
 261
 262 ProgramCompiler::Visitor::Visitor():
 263         stage(0)
 264 { }
 265
 266 void ProgramCompiler::Visitor::apply(Stage &s)
 267 {
 268         SetForScope<Stage *> set(stage, &s);
 269         stage->content.visit(*this);
 270 }
 271
 272
 273 ProgramCompiler::BlockModifier::BlockModifier():
 274         remove_node(false)
 275 { }
 276
 277 void ProgramCompiler::BlockModifier::flatten_block(Block &block)
 278 {
 279         insert_nodes.insert(insert_nodes.end(), block.body.begin(), block.body.end());
 280         remove_node = true;
 281 }
 282
 283 void ProgramCompiler::BlockModifier::apply_and_increment(Block &block, list<RefPtr<Node> >::iterator &i)
 284 {
 285         block.body.insert(i, insert_nodes.begin(), insert_nodes.end());
 286         insert_nodes.clear();
 287
 288         if(remove_node)
 289                 block.body.erase(i++);
 290         else
 291                 ++i;
 292         remove_node = false;
 293 }
 294
 295 void ProgramCompiler::BlockModifier::visit(Block &block)
 296 {
 297         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 298         {
 299                 (*i)->visit(*this);
 300                 apply_and_increment(block, i);
 301         }
 302 }
 303
 304
 305 ProgramCompiler::Formatter::Formatter():
 306         indent(0),
 307         parameter_list(false),
 308         else_if(0)
 309 { }
 310
 311 void ProgramCompiler::Formatter::apply(ProgramSyntax::Stage &s)
 312 {
 313         GLApi api = get_gl_api();
 314         const Version &ver = s.required_version;
 315
 316         if(ver)
 317         {
 318                 formatted += format("#version %d%02d", ver.major, ver.minor);
 319                 if(api==OPENGL_ES2 && ver>=Version(3, 0))
 320                         formatted += " es";
 321                 formatted += '\n';
 322         }
 323
 324         Visitor::apply(s);
 325 }
 326
 327 void ProgramCompiler::Formatter::visit(Literal &literal)
 328 {
 329         formatted += literal.token;
 330 }
 331
 332 void ProgramCompiler::Formatter::visit(ParenthesizedExpression &parexpr)
 333 {
 334         formatted += '(';
 335         parexpr.expression->visit(*this);
 336         formatted += ')';
 337 }
 338
 339 void ProgramCompiler::Formatter::visit(VariableReference &var)
 340 {
 341         formatted += var.name;
 342 }
 343
 344 void ProgramCompiler::Formatter::visit(MemberAccess &memacc)
 345 {
 346         memacc.left->visit(*this);
 347         formatted += format(".%s", memacc.member);
 348 }
 349
 350 void ProgramCompiler::Formatter::visit(UnaryExpression &unary)
 351 {
 352         if(unary.prefix)
 353                 formatted += unary.oper;
 354         unary.expression->visit(*this);
 355         if(!unary.prefix)
 356                 formatted += unary.oper;
 357 }
 358
 359 void ProgramCompiler::Formatter::visit(BinaryExpression &binary)
 360 {
 361         binary.left->visit(*this);
 362         formatted += binary.oper;
 363         binary.right->visit(*this);
 364         formatted += binary.after;
 365 }
 366
 367 void ProgramCompiler::Formatter::visit(Assignment &assign)
 368 {
 369         assign.left->visit(*this);
 370         formatted += format(" %s ", assign.oper);
 371         assign.right->visit(*this);
 372 }
 373
 374 void ProgramCompiler::Formatter::visit(FunctionCall &call)
 375 {
 376         formatted += format("%s(", call.name);
 377         for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
 378         {
 379                 if(i!=call.arguments.begin())
 380                         formatted += ", ";
 381                 (*i)->visit(*this);
 382         }
 383         formatted += ')';
 384 }
 385
 386 void ProgramCompiler::Formatter::visit(ExpressionStatement &expr)
 387 {
 388         expr.expression->visit(*this);
 389         formatted += ';';
 390 }
 391
 392 void ProgramCompiler::Formatter::visit(Block &block)
 393 {
 394         if(else_if)
 395                 --else_if;
 396
 397         unsigned brace_indent = indent;
 398         bool use_braces = (block.use_braces || (indent && block.body.size()!=1));
 399         if(use_braces)
 400                 formatted += format("%s{\n", string(brace_indent*2, ' '));
 401
 402         SetForScope<unsigned> set(indent, indent+(indent>0 || use_braces));
 403         string spaces(indent*2, ' ');
 404         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 405         {
 406                 if(i!=block.body.begin())
 407                         formatted += '\n';
 408                 formatted += spaces;
 409                 (*i)->visit(*this);
 410                 else_if = 0;
 411         }
 412
 413         if(use_braces)
 414                 formatted += format("\n%s}", string(brace_indent*2, ' '));
 415 }
 416
 417 void ProgramCompiler::Formatter::visit(Import &import)
 418 {
 419         formatted += format("import %s;", import.module);
 420 }
 421
 422 void ProgramCompiler::Formatter::visit(Precision &prec)
 423 {
 424         formatted += format("precision %s %s;", prec.precision, prec.type);
 425 }
 426
 427 void ProgramCompiler::Formatter::visit(Layout &layout)
 428 {
 429         formatted += "layout(";
 430         for(vector<Layout::Qualifier>::const_iterator i=layout.qualifiers.begin(); i!=layout.qualifiers.end(); ++i)
 431         {
 432                 if(i!=layout.qualifiers.begin())
 433                         formatted += ", ";
 434                 formatted += i->identifier;
 435                 if(!i->value.empty())
 436                         formatted += format("=%s", i->value);
 437         }
 438         formatted += ')';
 439 }
 440
 441 void ProgramCompiler::Formatter::visit(InterfaceLayout &layout)
 442 {
 443         layout.layout.visit(*this);
 444         formatted += format(" %s;", layout.interface);
 445 }
 446
 447 void ProgramCompiler::Formatter::visit(StructDeclaration &strct)
 448 {
 449         formatted += format("struct %s\n", strct.name);
 450         strct.members.visit(*this);
 451         formatted += ';';
 452 }
 453
 454 void ProgramCompiler::Formatter::visit(VariableDeclaration &var)
 455 {
 456         if(var.layout)
 457         {
 458                 var.layout->visit(*this);
 459                 formatted += ' ';
 460         }
 461         if(var.constant)
 462                 formatted += "const ";
 463         if(!var.interpolation.empty())
 464                 formatted += format("%s ", var.interpolation);
 465         if(!var.sampling.empty())
 466                 formatted += format("%s ", var.sampling);
 467         if(!var.interface.empty() && var.interface!=block_interface)
 468         {
 469                 string interface = var.interface;
 470                 if(stage->required_version<Version(1, 30))
 471                 {
 472                         if(stage->type==VERTEX && var.interface=="in")
 473                                 interface = "attribute";
 474                         else if((stage->type==VERTEX && var.interface=="out") || (stage->type==FRAGMENT && var.interface=="in"))
 475                                 interface = "varying";
 476                 }
 477                 formatted += format("%s ", interface);
 478         }
 479         if(!var.precision.empty())
 480                 formatted += format("%s ", var.precision);
 481         formatted += format("%s %s", var.type, var.name);
 482         if(var.array)
 483         {
 484                 formatted += '[';
 485                 if(var.array_size)
 486                         var.array_size->visit(*this);
 487                 formatted += ']';
 488         }
 489         if(var.init_expression)
 490         {
 491                 formatted += " = ";
 492                 var.init_expression->visit(*this);
 493         }
 494         if(!parameter_list)
 495                 formatted += ';';
 496 }
 497
 498 void ProgramCompiler::Formatter::visit(InterfaceBlock &iface)
 499 {
 500         SetForScope<string> set(block_interface, iface.interface);
 501         formatted += format("%s %s\n", iface.interface, iface.name);
 502         iface.members.visit(*this);
 503         formatted += ';';
 504 }
 505
 506 void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 507 {
 508         formatted += format("%s %s(", func.return_type, func.name);
 509         for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 510         {
 511                 if(i!=func.parameters.begin())
 512                         formatted += ", ";
 513                 SetFlag set(parameter_list);
 514                 (*i)->visit(*this);
 515         }
 516         formatted += ')';
 517         if(func.definition==&func)
 518         {
 519                 formatted += '\n';
 520                 func.body.visit(*this);
 521         }
 522         else
 523                 formatted += ';';
 524 }
 525
 526 void ProgramCompiler::Formatter::visit(Conditional &cond)
 527 {
 528         if(else_if)
 529                 formatted.replace(formatted.rfind('\n'), string::npos, 1, ' ');
 530
 531         indent -= else_if;
 532
 533         formatted += "if(";
 534         cond.condition->visit(*this);
 535         formatted += ")\n";
 536
 537         cond.body.visit(*this);
 538         if(!cond.else_body.body.empty())
 539         {
 540                 formatted += format("\n%selse\n", string(indent*2, ' '));
 541                 SetForScope<unsigned> set(else_if, 2);
 542                 cond.else_body.visit(*this);
 543         }
 544 }
 545
 546 void ProgramCompiler::Formatter::visit(Iteration &iter)
 547 {
 548         formatted += "for(";
 549         iter.init_statement->visit(*this);
 550         formatted += ' ';
 551         iter.condition->visit(*this);
 552         formatted += "; ";
 553         iter.loop_expression->visit(*this);
 554         formatted += ")\n";
 555         iter.body.visit(*this);
 556 }
 557
 558 void ProgramCompiler::Formatter::visit(Return &ret)
 559 {
 560         formatted += "return";
 561         if(ret.expression)
 562         {
 563                 formatted += ' ';
 564                 ret.expression->visit(*this);
 565         }
 566         formatted += ';';
 567 }
 568
 569 void ProgramCompiler::Formatter::visit(Jump &jump)
 570 {
 571         formatted += jump.keyword;
 572         formatted += ';';
 573 }
 574
 575
 576 ProgramCompiler::DeclarationCombiner::DeclarationCombiner():
 577         toplevel(true)
 578 { }
 579
 580 void ProgramCompiler::DeclarationCombiner::visit(Block &block)
 581 {
 582         if(!toplevel)
 583                 return;
 584
 585         SetForScope<bool> set(toplevel, false);
 586         BlockModifier::visit(block);
 587 }
 588
 589 void ProgramCompiler::DeclarationCombiner::visit(FunctionDeclaration &func)
 590 {
 591         vector<FunctionDeclaration *> &decls = functions[func.name];
 592         if(func.definition)
 593         {
 594                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 595                 {
 596                         (*i)->definition = func.definition;
 597                         (*i)->body.body.clear();
 598                 }
 599         }
 600         decls.push_back(&func);
 601 }
 602
 603 void ProgramCompiler::DeclarationCombiner::visit(VariableDeclaration &var)
 604 {
 605         VariableDeclaration *&ptr = variables[var.name];
 606         if(ptr)
 607         {
 608                 ptr->type = var.type;
 609                 if(var.init_expression)
 610                         ptr->init_expression = var.init_expression;
 611                 remove_node = true;
 612         }
 613         else
 614                 ptr = &var;
 615 }
 616
 617
 618 ProgramCompiler::VariableResolver::VariableResolver():
 619         anonymous(false),
 620         record_target(false),
 621         assignment_target(0),
 622         self_referencing(false)
 623 { }
 624
 625 void ProgramCompiler::VariableResolver::apply(Stage &s)
 626 {
 627         SetForScope<Stage *> set(stage, &s);
 628         Stage *builtins = get_builtins(stage->type);
 629         if(builtins)
 630                 blocks.push_back(&builtins->content);
 631         stage->content.visit(*this);
 632         if(builtins)
 633                 blocks.pop_back();
 634 }
 635
 636 void ProgramCompiler::VariableResolver::visit(Block &block)
 637 {
 638         blocks.push_back(&block);
 639         block.variables.clear();
 640         TraversingVisitor::visit(block);
 641         blocks.pop_back();
 642 }
 643
 644 void ProgramCompiler::VariableResolver::visit(VariableReference &var)
 645 {
 646         var.declaration = 0;
 647         type = 0;
 648         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 649         {
 650                 --i;
 651                 map<string, VariableDeclaration *>::iterator j = (*i)->variables.find(var.name);
 652                 if(j!=(*i)->variables.end())
 653                 {
 654                         var.declaration = j->second;
 655                         type = j->second->type_declaration;
 656                         break;
 657                 }
 658         }
 659
 660         if(record_target)
 661         {
 662                 if(assignment_target)
 663                 {
 664                         record_target = false;
 665                         assignment_target = 0;
 666                 }
 667                 else
 668                         assignment_target = var.declaration;
 669         }
 670         else if(var.declaration && var.declaration==assignment_target)
 671                 self_referencing = true;
 672 }
 673
 674 void ProgramCompiler::VariableResolver::visit(MemberAccess &memacc)
 675 {
 676         type = 0;
 677         TraversingVisitor::visit(memacc);
 678         memacc.declaration = 0;
 679         if(type)
 680         {
 681                 map<string, VariableDeclaration *>::iterator i = type->members.variables.find(memacc.member);
 682                 if(i!=type->members.variables.end())
 683                 {
 684                         memacc.declaration = i->second;
 685                         type = i->second->type_declaration;
 686                 }
 687                 else
 688                         type = 0;
 689         }
 690 }
 691
 692 void ProgramCompiler::VariableResolver::visit(BinaryExpression &binary)
 693 {
 694         if(binary.oper=="[")
 695         {
 696                 {
 697                         SetForScope<bool> set(record_target, false);
 698                         binary.right->visit(*this);
 699                 }
 700                 type = 0;
 701                 binary.left->visit(*this);
 702         }
 703         else
 704         {
 705                 TraversingVisitor::visit(binary);
 706                 type = 0;
 707         }
 708 }
 709
 710 void ProgramCompiler::VariableResolver::visit(Assignment &assign)
 711 {
 712         {
 713                 SetFlag set(record_target);
 714                 assignment_target = 0;
 715                 assign.left->visit(*this);
 716         }
 717
 718         self_referencing = false;
 719         assign.right->visit(*this);
 720
 721         assign.self_referencing = (self_referencing || assign.oper!="=");
 722         assign.target_declaration = assignment_target;
 723 }
 724
 725 void ProgramCompiler::VariableResolver::visit(StructDeclaration &strct)
 726 {
 727         TraversingVisitor::visit(strct);
 728         blocks.back()->types[strct.name] = &strct;
 729 }
 730
 731 void ProgramCompiler::VariableResolver::visit(VariableDeclaration &var)
 732 {
 733         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 734         {
 735                 --i;
 736                 map<string, StructDeclaration *>::iterator j = (*i)->types.find(var.type);
 737                 if(j!=(*i)->types.end())
 738                         var.type_declaration = j->second;
 739         }
 740
 741         if(!block_interface.empty() && var.interface.empty())
 742                 var.interface = block_interface;
 743
 744         TraversingVisitor::visit(var);
 745         blocks.back()->variables[var.name] = &var;
 746         if(anonymous && blocks.size()>1)
 747                 blocks[blocks.size()-2]->variables[var.name] = &var;
 748 }
 749
 750 void ProgramCompiler::VariableResolver::visit(InterfaceBlock &iface)
 751 {
 752         SetFlag set(anonymous);
 753         SetForScope<string> set2(block_interface, iface.interface);
 754         TraversingVisitor::visit(iface);
 755 }
 756
 757
 758 void ProgramCompiler::FunctionResolver::visit(FunctionCall &call)
 759 {
 760         map<string, vector<FunctionDeclaration *> >::iterator i = functions.find(call.name);
 761         if(i!=functions.end())
 762                 call.declaration = i->second.back();
 763
 764         TraversingVisitor::visit(call);
 765 }
 766
 767 void ProgramCompiler::FunctionResolver::visit(FunctionDeclaration &func)
 768 {
 769         vector<FunctionDeclaration *> &decls = functions[func.name];
 770         if(func.definition)
 771         {
 772                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 773                         (*i)->definition = func.definition;
 774                 decls.clear();
 775                 decls.push_back(&func);
 776         }
 777         else if(!decls.empty() && decls.back()->definition)
 778                 func.definition = decls.back()->definition;
 779         else
 780                 decls.push_back(&func);
 781
 782         TraversingVisitor::visit(func);
 783 }
 784
 785
 786 ProgramCompiler::InterfaceGenerator::InterfaceGenerator():
 787         scope_level(0)
 788 { }
 789
 790 string ProgramCompiler::InterfaceGenerator::get_out_prefix(StageType type)
 791 {
 792         if(type==VERTEX)
 793                 return "_vs_out_";
 794         else if(type==GEOMETRY)
 795                 return "_gs_out_";
 796         else
 797                 return string();
 798 }
 799
 800 void ProgramCompiler::InterfaceGenerator::apply(Stage &s)
 801 {
 802         SetForScope<Stage *> set(stage, &s);
 803         if(stage->previous)
 804                 in_prefix = get_out_prefix(stage->previous->type);
 805         out_prefix = get_out_prefix(stage->type);
 806         stage->content.visit(*this);
 807 }
 808
 809 void ProgramCompiler::InterfaceGenerator::visit(Block &block)
 810 {
 811         SetForScope<unsigned> set(scope_level, scope_level+1);
 812         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 813         {
 814                 (*i)->visit(*this);
 815
 816                 if(scope_level==1)
 817                 {
 818                         for(map<string, RefPtr<VariableDeclaration> >::iterator j=iface_declarations.begin(); j!=iface_declarations.end(); ++j)
 819                         {
 820                                 list<RefPtr<Node> >::iterator k = block.body.insert(i, j->second);
 821                                 (*k)->visit(*this);
 822                         }
 823                         iface_declarations.clear();
 824                 }
 825
 826                 apply_and_increment(block, i);
 827         }
 828 }
 829
 830 string ProgramCompiler::InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
 831 {
 832         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
 833         return prefix+name.substr(offset);
 834 }
 835
 836 bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
 837 {
 838         const map<string, VariableDeclaration *> &stage_vars = (iface=="in" ? stage->in_variables : stage->out_variables);
 839         if(stage_vars.count(name) || iface_declarations.count(name))
 840                 return false;
 841
 842         VariableDeclaration* iface_var = new VariableDeclaration;
 843         iface_var->sampling = var.sampling;
 844         iface_var->interface = iface;
 845         iface_var->type = var.type;
 846         iface_var->type_declaration = var.type_declaration;
 847         iface_var->name = name;
 848         if(stage->type==GEOMETRY)
 849                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
 850         else
 851                 iface_var->array = var.array;
 852         if(iface_var->array)
 853                 iface_var->array_size = var.array_size;
 854         if(iface=="in")
 855                 iface_var->linked_declaration = &var;
 856         iface_declarations[name] = iface_var;
 857
 858         return true;
 859 }
 860
 861 void ProgramCompiler::InterfaceGenerator::insert_assignment(const string &left, ProgramSyntax::Expression *right)
 862 {
 863         Assignment *assign = new Assignment;
 864         VariableReference *ref = new VariableReference;
 865         ref->name = left;
 866         assign->left = ref;
 867         assign->oper = "=";
 868         assign->right = right;
 869
 870         ExpressionStatement *stmt = new ExpressionStatement;
 871         stmt->expression = assign;
 872         stmt->visit(*this);
 873         insert_nodes.push_back(stmt);
 874 }
 875
 876 void ProgramCompiler::InterfaceGenerator::visit(VariableReference &var)
 877 {
 878         if(var.declaration || !stage->previous)
 879                 return;
 880         if(iface_declarations.count(var.name))
 881                 return;
 882
 883         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 884         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
 885         if(i==prev_out.end())
 886                 i = prev_out.find(in_prefix+var.name);
 887         if(i!=prev_out.end())
 888         {
 889                 generate_interface(*i->second, "in", i->second->name);
 890                 var.name = i->second->name;
 891         }
 892 }
 893
 894 void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &var)
 895 {
 896         if(var.interface=="out")
 897         {
 898                 if(scope_level==1)
 899                         stage->out_variables[var.name] = &var;
 900                 else if(generate_interface(var, "out", change_prefix(var.name, string())))
 901                 {
 902                         remove_node = true;
 903                         if(var.init_expression)
 904                         {
 905                                 insert_assignment(var.name, var.init_expression->clone());
 906                                 return;
 907                         }
 908                 }
 909         }
 910         else if(var.interface=="in")
 911         {
 912                 stage->in_variables[var.name] = &var;
 913                 if(var.linked_declaration)
 914                         var.linked_declaration->linked_declaration = &var;
 915                 else if(stage->previous)
 916                 {
 917                         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 918                         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
 919                         if(i!=prev_out.end())
 920                         {
 921                                 var.linked_declaration = i->second;
 922                                 i->second->linked_declaration = &var;
 923                         }
 924                 }
 925         }
 926
 927         TraversingVisitor::visit(var);
 928 }
 929
 930 void ProgramCompiler::InterfaceGenerator::visit(Passthrough &pass)
 931 {
 932         vector<VariableDeclaration *> pass_vars;
 933
 934         for(map<string, VariableDeclaration *>::const_iterator i=stage->in_variables.begin(); i!=stage->in_variables.end(); ++i)
 935                 pass_vars.push_back(i->second);
 936         for(map<string, RefPtr<VariableDeclaration> >::const_iterator i=iface_declarations.begin(); i!=iface_declarations.end(); ++i)
 937                 if(i->second->interface=="in")
 938                         pass_vars.push_back(i->second.get());
 939
 940         if(stage->previous)
 941         {
 942                 const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 943                 for(map<string, VariableDeclaration *>::const_iterator i=prev_out.begin(); i!=prev_out.end(); ++i)
 944                 {
 945                         bool linked = false;
 946                         for(vector<VariableDeclaration *>::const_iterator j=pass_vars.begin(); (!linked && j!=pass_vars.end()); ++j)
 947                                 linked = ((*j)->linked_declaration==i->second);
 948
 949                         if(!linked && generate_interface(*i->second, "in", i->second->name))
 950                                 pass_vars.push_back(i->second);
 951                 }
 952         }
 953
 954         if(stage->type==GEOMETRY)
 955         {
 956                 VariableReference *ref = new VariableReference;
 957                 ref->name = "gl_in";
 958
 959                 BinaryExpression *subscript = new BinaryExpression;
 960                 subscript->left = ref;
 961                 subscript->oper = "[";
 962                 subscript->right = pass.subscript;
 963                 subscript->after = "]";
 964
 965                 MemberAccess *memacc = new MemberAccess;
 966                 memacc->left = subscript;
 967                 memacc->member = "gl_Position";
 968
 969                 insert_assignment("gl_Position", memacc);
 970         }
 971
 972         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
 973         {
 974                 string out_name = change_prefix((*i)->name, out_prefix);
 975                 generate_interface(**i, "out", out_name);
 976
 977                 VariableReference *ref = new VariableReference;
 978                 ref->name = (*i)->name;
 979                 if(pass.subscript)
 980                 {
 981                         BinaryExpression *subscript = new BinaryExpression;
 982                         subscript->left = ref;
 983                         subscript->oper = "[";
 984                         subscript->right = pass.subscript;
 985                         subscript->after = "]";
 986                         insert_assignment(out_name, subscript);
 987                 }
 988                 else
 989                         insert_assignment(out_name, ref);
 990         }
 991
 992         remove_node = true;
 993 }
 994
 995
 996 ProgramCompiler::DeclarationReorderer::DeclarationReorderer():
 997         scope_level(0),
 998         kind(NO_DECLARATION)
 999 { }
1000
1001 void ProgramCompiler::DeclarationReorderer::visit(FunctionCall &call)
1002 {
1003         FunctionDeclaration *def = call.declaration;
1004         if(def)
1005                 def = def->definition;
1006         if(def && !ordered_funcs.count(def))
1007                 needed_funcs.insert(def);
1008 }
1009
1010 void ProgramCompiler::DeclarationReorderer::visit(Block &block)
1011 {
1012         SetForScope<unsigned> set(scope_level, scope_level+1);
1013         if(scope_level>1)
1014                 return Visitor::visit(block);
1015
1016         list<RefPtr<Node> >::iterator struct_insert_point = block.body.end();
1017         list<RefPtr<Node> >::iterator variable_insert_point = block.body.end();
1018         list<RefPtr<Node> >::iterator function_insert_point = block.body.end();
1019         unsigned unordered_func_count = 0;
1020         bool ordered_any_funcs = false;
1021
1022         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
1023         {
1024                 kind = NO_DECLARATION;
1025                 (*i)->visit(*this);
1026
1027                 bool moved = false;
1028                 if(kind==STRUCT && struct_insert_point!=block.body.end())
1029                 {
1030                         block.body.insert(struct_insert_point, *i);
1031                         moved = true;
1032                 }
1033                 else if(kind>STRUCT && struct_insert_point==block.body.end())
1034                         struct_insert_point = i;
1035
1036                 if(kind==VARIABLE && variable_insert_point!=block.body.end())
1037                 {
1038                         block.body.insert(variable_insert_point, *i);
1039                         moved = true;
1040                 }
1041                 else if(kind>VARIABLE && variable_insert_point==block.body.end())
1042                         variable_insert_point = i;
1043
1044                 if(kind==FUNCTION)
1045                 {
1046                         if(function_insert_point==block.body.end())
1047                                 function_insert_point = i;
1048
1049                         if(needed_funcs.empty())
1050                         {
1051                                 ordered_funcs.insert(i->get());
1052                                 if(i!=function_insert_point)
1053                                 {
1054                                         block.body.insert(function_insert_point, *i);
1055                                         moved = true;
1056                                 }
1057                                 else
1058                                         ++function_insert_point;
1059                                 ordered_any_funcs = true;
1060                         }
1061                         else
1062                                 ++unordered_func_count;
1063                 }
1064
1065                 if(moved)
1066                 {
1067                         if(function_insert_point==i)
1068                                 ++function_insert_point;
1069                         block.body.erase(i++);
1070                 }
1071                 else
1072                         ++i;
1073
1074                 if(i==block.body.end() && unordered_func_count)
1075                 {
1076                         if(!ordered_any_funcs)
1077                                 // A subset of the remaining functions forms a recursive loop
1078                                 /* TODO pick a function and move it up, adding any necessary
1079                                 declarations */
1080                                 break;
1081
1082                         i = function_insert_point;
1083                         unordered_func_count = 0;
1084                 }
1085         }
1086 }
1087
1088 void ProgramCompiler::DeclarationReorderer::visit(ProgramSyntax::VariableDeclaration &var)
1089 {
1090         Visitor::visit(var);
1091         kind = VARIABLE;
1092 }
1093
1094 void ProgramCompiler::DeclarationReorderer::visit(FunctionDeclaration &func)
1095 {
1096         needed_funcs.clear();
1097         func.body.visit(*this);
1098         needed_funcs.erase(&func);
1099         kind = FUNCTION;
1100 }
1101
1102
1103 ProgramCompiler::InlineableFunctionLocator::InlineableFunctionLocator():
1104         in_function(0)
1105 { }
1106
1107 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionCall &call)
1108 {
1109         FunctionDeclaration *def = call.declaration;
1110         if(def && def->definition!=def)
1111                 def = def->definition;
1112
1113         if(def)
1114         {
1115                 unsigned &count = refcounts[def];
1116                 ++count;
1117                 if(count>1 || def==in_function)
1118                         inlineable.erase(def);
1119         }
1120
1121         TraversingVisitor::visit(call);
1122 }
1123
1124 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionDeclaration &func)
1125 {
1126         unsigned &count = refcounts[func.definition];
1127         if(!count && func.parameters.empty())
1128                 inlineable.insert(func.definition);
1129
1130         SetForScope<FunctionDeclaration *> set(in_function, &func);
1131         TraversingVisitor::visit(func);
1132 }
1133
1134
1135 ProgramCompiler::FunctionInliner::FunctionInliner():
1136         extract_result(0)
1137 { }
1138
1139 ProgramCompiler::FunctionInliner::FunctionInliner(const set<FunctionDeclaration *> &in):
1140         inlineable(in),
1141         extract_result(0)
1142 { }
1143
1144 void ProgramCompiler::FunctionInliner::visit_and_inline(RefPtr<Expression> &ptr)
1145 {
1146         inline_result = 0;
1147         ptr->visit(*this);
1148         if(inline_result)
1149                 ptr = inline_result;
1150 }
1151
1152 void ProgramCompiler::FunctionInliner::visit(Block &block)
1153 {
1154         if(extract_result)
1155                 --extract_result;
1156
1157         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
1158         {
1159                 (*i)->visit(*this);
1160                 if(extract_result)
1161                         --extract_result;
1162         }
1163 }
1164
1165 void ProgramCompiler::FunctionInliner::visit(UnaryExpression &unary)
1166 {
1167         visit_and_inline(unary.expression);
1168         inline_result = 0;
1169 }
1170
1171 void ProgramCompiler::FunctionInliner::visit(BinaryExpression &binary)
1172 {
1173         visit_and_inline(binary.left);
1174         visit_and_inline(binary.right);
1175         inline_result = 0;
1176 }
1177
1178 void ProgramCompiler::FunctionInliner::visit(MemberAccess &memacc)
1179 {
1180         visit_and_inline(memacc.left);
1181         inline_result = 0;
1182 }
1183
1184 void ProgramCompiler::FunctionInliner::visit(FunctionCall &call)
1185 {
1186         for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
1187                 visit_and_inline(*i);
1188
1189         FunctionDeclaration *def = call.declaration;
1190         if(def && def->definition!=def)
1191                 def = def->definition;
1192
1193         if(def && inlineable.count(def))
1194         {
1195                 extract_result = 2;
1196                 def->visit(*this);
1197         }
1198         else
1199                 inline_result = 0;
1200 }
1201
1202 void ProgramCompiler::FunctionInliner::visit(Return &ret)
1203 {
1204         TraversingVisitor::visit(ret);
1205
1206         if(extract_result)
1207                 inline_result = ret.expression->clone();
1208 }
1209
1210
1211 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator():
1212         variable_values(0),
1213         result(0.0f),
1214         result_valid(false)
1215 { }
1216
1217 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator(const ValueMap &v):
1218         variable_values(&v),
1219         result(0.0f),
1220         result_valid(false)
1221 { }
1222
1223 void ProgramCompiler::ExpressionEvaluator::visit(Literal &literal)
1224 {
1225         if(literal.token=="true")
1226                 result = 1.0f;
1227         else if(literal.token=="false")
1228                 result = 0.0f;
1229         else
1230                 result = lexical_cast<float>(literal.token);
1231         result_valid = true;
1232 }
1233
1234 void ProgramCompiler::ExpressionEvaluator::visit(ParenthesizedExpression &parexp)
1235 {
1236         parexp.expression->visit(*this);
1237 }
1238
1239 void ProgramCompiler::ExpressionEvaluator::visit(VariableReference &var)
1240 {
1241         if(!var.declaration)
1242                 return;
1243
1244         if(variable_values)
1245         {
1246                 ValueMap::const_iterator i = variable_values->find(var.declaration);
1247                 if(i!=variable_values->end())
1248                         i->second->visit(*this);
1249         }
1250         else if(var.declaration->init_expression)
1251                 var.declaration->init_expression->visit(*this);
1252 }
1253
1254 void ProgramCompiler::ExpressionEvaluator::visit(UnaryExpression &unary)
1255 {
1256         result_valid = false;
1257         unary.expression->visit(*this);
1258         if(!result_valid)
1259                 return;
1260
1261         if(unary.oper=="!")
1262                 result = !result;
1263         else
1264                 result_valid = false;
1265 }
1266
1267 void ProgramCompiler::ExpressionEvaluator::visit(BinaryExpression &binary)
1268 {
1269         result_valid = false;
1270         binary.left->visit(*this);
1271         if(!result_valid)
1272                 return;
1273
1274         float left_result = result;
1275         result_valid = false;
1276         binary.right->visit(*this);
1277         if(!result_valid)
1278                 return;
1279
1280         if(binary.oper=="<")
1281                 result = (left_result<result);
1282         else if(binary.oper=="<=")
1283                 result = (left_result<=result);
1284         else if(binary.oper==">")
1285                 result = (left_result>result);
1286         else if(binary.oper==">=")
1287                 result = (left_result>=result);
1288         else if(binary.oper=="==")
1289                 result = (left_result==result);
1290         else if(binary.oper=="!=")
1291                 result = (left_result!=result);
1292         else if(binary.oper=="&&")
1293                 result = (left_result && result);
1294         else if(binary.oper=="||")
1295                 result = (left_result || result);
1296         else
1297                 result_valid = false;
1298 }
1299
1300
1301 ProgramCompiler::ConstantConditionEliminator::ConstantConditionEliminator():
1302         scope_level(0),
1303         record_only(false)
1304 { }
1305
1306 void ProgramCompiler::ConstantConditionEliminator::visit(Block &block)
1307 {
1308         SetForScope<unsigned> set(scope_level, scope_level+1);
1309         BlockModifier::visit(block);
1310
1311         for(map<string, VariableDeclaration *>::const_iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
1312                 variable_values.erase(i->second);
1313 }
1314
1315 void ProgramCompiler::ConstantConditionEliminator::visit(UnaryExpression &unary)
1316 {
1317         if(VariableReference *var = dynamic_cast<VariableReference *>(unary.expression.get()))
1318                 if(unary.oper=="++" || unary.oper=="--")
1319                         variable_values.erase(var->declaration);
1320 }
1321
1322 void ProgramCompiler::ConstantConditionEliminator::visit(Assignment &assign)
1323 {
1324         variable_values.erase(assign.target_declaration);
1325 }
1326
1327 void ProgramCompiler::ConstantConditionEliminator::visit(VariableDeclaration &var)
1328 {
1329         if(var.constant || scope_level>1)
1330                 variable_values[&var] = var.init_expression.get();
1331 }
1332
1333 void ProgramCompiler::ConstantConditionEliminator::visit(Conditional &cond)
1334 {
1335         if(!record_only)
1336         {
1337                 ExpressionEvaluator eval(variable_values);
1338                 cond.condition->visit(eval);
1339                 if(eval.result_valid)
1340                 {
1341                         flatten_block(eval.result ? cond.body : cond.else_body);
1342                         return;
1343                 }
1344         }
1345
1346         TraversingVisitor::visit(cond);
1347 }
1348
1349 void ProgramCompiler::ConstantConditionEliminator::visit(Iteration &iter)
1350 {
1351         if(!record_only)
1352         {
1353                 if(iter.condition)
1354                 {
1355                         /* If the loop condition is always false on the first iteration, the
1356                         entire loop can be removed */
1357                         if(iter.init_statement)
1358                                 iter.init_statement->visit(*this);
1359                         ExpressionEvaluator eval(variable_values);
1360                         iter.condition->visit(eval);
1361                         if(eval.result_valid && !eval.result)
1362                         {
1363                                 remove_node = true;
1364                                 return;
1365                         }
1366                 }
1367
1368                 /* Record all assignments that occur inside the loop body so those
1369                 variables won't be considered as constant */
1370                 SetFlag set_record(record_only);
1371                 TraversingVisitor::visit(iter);
1372         }
1373
1374         TraversingVisitor::visit(iter);
1375
1376         if(VariableDeclaration *init_decl = dynamic_cast<VariableDeclaration *>(iter.init_statement.get()))
1377                 variable_values.erase(init_decl);
1378 }
1379
1380
1381 ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
1382         aggregate(0),
1383         assignment(0),
1384         assignment_target(false),
1385         global_scope(true)
1386 { }
1387
1388 void ProgramCompiler::UnusedVariableLocator::apply(Stage &s)
1389 {
1390         variables.push_back(BlockVariableMap());
1391         Visitor::apply(s);
1392         BlockVariableMap &global_variables = variables.back();
1393         for(BlockVariableMap::iterator i=global_variables.begin(); i!=global_variables.end(); ++i)
1394         {
1395                 if(i->first->interface=="out" && (s.type==FRAGMENT || i->first->linked_declaration || !i->first->name.compare(0, 3, "gl_")))
1396                         continue;
1397                 if(!i->second.referenced)
1398                 {
1399                         unused_nodes.insert(i->first);
1400                         clear_assignments(i->second, true);
1401                 }
1402         }
1403         variables.pop_back();
1404 }
1405
1406 void ProgramCompiler::UnusedVariableLocator::visit(VariableReference &var)
1407 {
1408         map<VariableDeclaration *, Node *>::iterator i = aggregates.find(var.declaration);
1409         if(i!=aggregates.end())
1410                 unused_nodes.erase(i->second);
1411
1412         if(var.declaration && !assignment_target)
1413         {
1414                 VariableInfo &var_info = variables.back()[var.declaration];
1415                 var_info.assignments.clear();
1416                 var_info.referenced = true;
1417         }
1418 }
1419
1420 void ProgramCompiler::UnusedVariableLocator::visit(MemberAccess &memacc)
1421 {
1422         TraversingVisitor::visit(memacc);
1423         unused_nodes.erase(memacc.declaration);
1424 }
1425
1426 void ProgramCompiler::UnusedVariableLocator::visit(BinaryExpression &binary)
1427 {
1428         if(binary.oper=="[")
1429         {
1430                 binary.left->visit(*this);
1431                 SetForScope<bool> set(assignment_target, false);
1432                 binary.right->visit(*this);
1433         }
1434         else
1435                 TraversingVisitor::visit(binary);
1436 }
1437
1438 void ProgramCompiler::UnusedVariableLocator::visit(Assignment &assign)
1439 {
1440         {
1441                 SetForScope<bool> set(assignment_target, !assign.self_referencing);
1442                 assign.left->visit(*this);
1443         }
1444         assign.right->visit(*this);
1445         assignment = &assign;
1446 }
1447
1448 void ProgramCompiler::UnusedVariableLocator::record_assignment(VariableDeclaration &var, Node &node, bool self_ref)
1449 {
1450         VariableInfo &var_info = variables.back()[&var];
1451         if(!self_ref)
1452                 clear_assignments(var_info, true);
1453         var_info.assignments.push_back(&node);
1454         var_info.conditionally_assigned = false;
1455 }
1456
1457 void ProgramCompiler::UnusedVariableLocator::clear_assignments(VariableInfo &var_info, bool mark_unused)
1458 {
1459         if(mark_unused)
1460         {
1461                 for(vector<Node *>::iterator i=var_info.assignments.begin(); i!=var_info.assignments.end(); ++i)
1462                         unused_nodes.insert(*i);
1463         }
1464         var_info.assignments.clear();
1465 }
1466
1467 void ProgramCompiler::UnusedVariableLocator::visit(ExpressionStatement &expr)
1468 {
1469         assignment = 0;
1470         TraversingVisitor::visit(expr);
1471         if(assignment && assignment->target_declaration)
1472                 record_assignment(*assignment->target_declaration, expr, assignment->self_referencing);
1473 }
1474
1475 void ProgramCompiler::UnusedVariableLocator::visit(StructDeclaration &strct)
1476 {
1477         SetForScope<Node *> set(aggregate, &strct);
1478         unused_nodes.insert(&strct);
1479         TraversingVisitor::visit(strct);
1480 }
1481
1482 void ProgramCompiler::UnusedVariableLocator::visit(VariableDeclaration &var)
1483 {
1484         if(aggregate)
1485                 aggregates[&var] = aggregate;
1486         else
1487         {
1488                 variables.back()[&var].local = true;
1489                 if(var.init_expression)
1490                         record_assignment(var, *var.init_expression, false);
1491         }
1492         unused_nodes.erase(var.type_declaration);
1493         TraversingVisitor::visit(var);
1494 }
1495
1496 void ProgramCompiler::UnusedVariableLocator::visit(InterfaceBlock &iface)
1497 {
1498         SetForScope<Node *> set(aggregate, &iface);
1499         unused_nodes.insert(&iface);
1500         TraversingVisitor::visit(iface);
1501 }
1502
1503 void ProgramCompiler::UnusedVariableLocator::visit(FunctionDeclaration &func)
1504 {
1505         variables.push_back(BlockVariableMap());
1506
1507         {
1508                 SetForScope<bool> set(global_scope, false);
1509                 for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1510                         (*i)->visit(*this);
1511                 func.body.visit(*this);
1512         }
1513
1514         BlockVariableMap &block_variables = variables.back();
1515         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1516                 i->second.conditionally_assigned = true;
1517         for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1518                 block_variables[i->get()].referenced = true;
1519         merge_down_variables();
1520 }
1521
1522 void ProgramCompiler::UnusedVariableLocator::merge_down_variables()
1523 {
1524         BlockVariableMap &parent_variables = variables[variables.size()-2];
1525         BlockVariableMap &block_variables = variables.back();
1526         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1527         {
1528                 if(i->second.local)
1529                 {
1530                         if(!i->second.referenced)
1531                                 unused_nodes.insert(i->first);
1532                         clear_assignments(i->second, true);
1533                         continue;
1534                 }
1535
1536                 BlockVariableMap::iterator j = parent_variables.find(i->first);
1537                 if(j==parent_variables.end())
1538                         parent_variables.insert(*i);
1539                 else
1540                 {
1541                         if(i->second.referenced || !i->second.conditionally_assigned)
1542                                 clear_assignments(j->second, !i->second.referenced);
1543                         j->second.conditionally_assigned = i->second.conditionally_assigned;
1544                         j->second.referenced |= i->second.referenced;
1545                         j->second.assignments.insert(j->second.assignments.end(), i->second.assignments.begin(), i->second.assignments.end());
1546                 }
1547         }
1548         variables.pop_back();
1549 }
1550
1551 void ProgramCompiler::UnusedVariableLocator::visit(Conditional &cond)
1552 {
1553         cond.condition->visit(*this);
1554         variables.push_back(BlockVariableMap());
1555         cond.body.visit(*this);
1556
1557         BlockVariableMap if_variables;
1558         swap(variables.back(), if_variables);
1559         cond.else_body.visit(*this);
1560
1561         BlockVariableMap &else_variables = variables.back();
1562         for(BlockVariableMap::iterator i=else_variables.begin(); i!=else_variables.end(); ++i)
1563         {
1564                 BlockVariableMap::iterator j = if_variables.find(i->first);
1565                 if(j!=if_variables.end())
1566                 {
1567                         i->second.assignments.insert(i->second.assignments.end(), j->second.assignments.begin(), j->second.assignments.end());
1568                         i->second.conditionally_assigned |= j->second.conditionally_assigned;
1569                         if_variables.erase(j);
1570                 }
1571                 else
1572                         i->second.conditionally_assigned = true;
1573         }
1574
1575         for(BlockVariableMap::iterator i=if_variables.begin(); i!=if_variables.end(); ++i)
1576         {
1577                 i->second.conditionally_assigned = true;
1578                 else_variables.insert(*i);
1579         }
1580
1581         merge_down_variables();
1582 }
1583
1584 void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
1585 {
1586         variables.push_back(BlockVariableMap());
1587         TraversingVisitor::visit(iter);
1588
1589         BlockVariableMap &block_variables = variables.back();
1590         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1591                 if(!i->second.local && i->second.referenced)
1592                         i->second.assignments.clear();
1593
1594         merge_down_variables();
1595 }
1596
1597
1598 ProgramCompiler::UnusedVariableLocator::VariableInfo::VariableInfo():
1599         local(false),
1600         conditionally_assigned(false),
1601         referenced(false)
1602 { }
1603
1604
1605 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionCall &call)
1606 {
1607         TraversingVisitor::visit(call);
1608
1609         unused_nodes.erase(call.declaration);
1610         if(call.declaration && call.declaration->definition!=call.declaration)
1611                 used_definitions.insert(call.declaration->definition);
1612 }
1613
1614 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionDeclaration &func)
1615 {
1616         TraversingVisitor::visit(func);
1617
1618         if((func.name!="main" || func.body.body.empty()) && !used_definitions.count(&func))
1619                 unused_nodes.insert(&func);
1620 }
1621
1622
1623 ProgramCompiler::NodeRemover::NodeRemover(const set<Node *> &r):
1624         to_remove(r)
1625 { }
1626
1627 void ProgramCompiler::NodeRemover::visit(Block &block)
1628 {
1629         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
1630         {
1631                 (*i)->visit(*this);
1632                 if(to_remove.count(i->get()))
1633                         block.body.erase(i++);
1634                 else
1635                         ++i;
1636         }
1637 }
1638
1639 void ProgramCompiler::NodeRemover::visit(VariableDeclaration &var)
1640 {
1641         if(to_remove.count(&var))
1642         {
1643                 stage->in_variables.erase(var.name);
1644                 stage->out_variables.erase(var.name);
1645                 stage->locations.erase(var.name);
1646                 if(var.linked_declaration)
1647                         var.linked_declaration->linked_declaration = 0;
1648         }
1649         else if(var.init_expression && to_remove.count(var.init_expression.get()))
1650                 var.init_expression = 0;
1651 }
1652
1653
1654 void ProgramCompiler::PrecisionRemover::visit(Precision &)
1655 {
1656         remove_node = true;
1657 }
1658
1659 void ProgramCompiler::PrecisionRemover::visit(VariableDeclaration &var)
1660 {
1661         var.precision.clear();
1662 }
1663
1664
1665 ProgramCompiler::DefaultPrecisionGenerator::DefaultPrecisionGenerator():
1666         toplevel(true)
1667 { }
1668
1669 void ProgramCompiler::DefaultPrecisionGenerator::visit(Block &block)
1670 {
1671         if(toplevel)
1672         {
1673                 SetForScope<bool> set(toplevel, false);
1674                 BlockModifier::visit(block);
1675         }
1676         else
1677                 Visitor::visit(block);
1678 }
1679
1680 void ProgramCompiler::DefaultPrecisionGenerator::visit(Precision &prec)
1681 {
1682         have_default.insert(prec.type);
1683 }
1684
1685 void ProgramCompiler::DefaultPrecisionGenerator::visit(VariableDeclaration &var)
1686 {
1687         if(var.type_declaration)
1688                 return;
1689
1690         string type = var.type;
1691         if(!type.compare(0, 3, "vec") || !type.compare(0, 3, "mat"))
1692                 type = "float";
1693         else if(!type.compare(0, 3, "ivec") || type=="uint")
1694                 type = "int";
1695
1696         if(!have_default.count(type))
1697         {
1698                 Precision *prec = new Precision;
1699                 if(!type.compare(0, 7, "sampler"))
1700                         prec->precision = "lowp";
1701                 else if(stage->type==FRAGMENT)
1702                         prec->precision = "mediump";
1703                 else
1704                         prec->precision = "highp";
1705                 prec->type = type;
1706                 insert_nodes.push_back(prec);
1707
1708                 have_default.insert(type);
1709         }
1710 }
1711
1712
1713 ProgramCompiler::LegacyConverter::LegacyConverter():
1714         target_api(get_gl_api()),
1715         target_version(get_glsl_version()),
1716         frag_out(0)
1717 { }
1718
1719 ProgramCompiler::LegacyConverter::LegacyConverter(const Version &v):
1720         target_api(get_gl_api()),
1721         target_version(v),
1722         frag_out(0)
1723 { }
1724
1725 bool ProgramCompiler::LegacyConverter::check_version(const Version &feature_version) const
1726 {
1727         if(target_version<feature_version)
1728                 return false;
1729         else if(stage->required_version<feature_version)
1730                 stage->required_version = feature_version;
1731
1732         return true;
1733 }
1734
1735 bool ProgramCompiler::LegacyConverter::supports_unified_interface_syntax() const
1736 {
1737         if(target_api==OPENGL_ES2)
1738                 return check_version(Version(3, 0));
1739         else
1740                 return check_version(Version(1, 30));
1741 }
1742
1743 void ProgramCompiler::LegacyConverter::visit(VariableReference &var)
1744 {
1745         if(var.declaration==frag_out && !supports_unified_interface_syntax())
1746         {
1747                 var.name = "gl_FragColor";
1748                 var.declaration = 0;
1749                 type = "vec4";
1750         }
1751         else if(var.declaration)
1752                 type = var.declaration->type;
1753         else
1754                 type = string();
1755 }
1756
1757 void ProgramCompiler::LegacyConverter::visit(Assignment &assign)
1758 {
1759         TraversingVisitor::visit(assign);
1760         if(assign.target_declaration==frag_out && !supports_unified_interface_syntax())
1761                 assign.target_declaration = 0;
1762 }
1763
1764 bool ProgramCompiler::LegacyConverter::supports_unified_sampling_functions() const
1765 {
1766         if(target_api==OPENGL_ES2)
1767                 return check_version(Version(3, 0));
1768         else
1769                 return check_version(Version(1, 30));
1770 }
1771
1772 void ProgramCompiler::LegacyConverter::visit(FunctionCall &call)
1773 {
1774         if(call.name=="texture" && !call.declaration && !supports_unified_sampling_functions())
1775         {
1776                 vector<RefPtr<Expression> >::iterator i = call.arguments.begin();
1777                 if(i!=call.arguments.end())
1778                 {
1779                         (*i)->visit(*this);
1780                         if(type=="sampler1D")
1781                                 call.name = "texture1D";
1782                         else if(type=="sampler2D")
1783                                 call.name = "texture2D";
1784                         else if(type=="sampler3D")
1785                                 call.name = "texture3D";
1786                         else if(type=="sampler1DShadow")
1787                                 call.name = "shadow1D";
1788                         else if(type=="sampler2DShadow")
1789                                 call.name = "shadow2D";
1790
1791                         for(; i!=call.arguments.end(); ++i)
1792                                 (*i)->visit(*this);
1793                 }
1794         }
1795         else
1796                 TraversingVisitor::visit(call);
1797 }
1798
1799 bool ProgramCompiler::LegacyConverter::supports_interface_layouts() const
1800 {
1801         if(target_api==OPENGL_ES2)
1802                 return check_version(Version(3, 0));
1803         else
1804                 return check_version(Version(3, 30));
1805 }
1806
1807 bool ProgramCompiler::LegacyConverter::supports_centroid_sampling() const
1808 {
1809         if(target_api==OPENGL_ES2)
1810                 return check_version(Version(3, 0));
1811         else
1812                 return check_version(Version(1, 20));
1813 }
1814
1815 bool ProgramCompiler::LegacyConverter::supports_sample_sampling() const
1816 {
1817         if(target_api==OPENGL_ES2)
1818                 return check_version(Version(3, 20));
1819         else
1820                 return check_version(Version(4, 0));
1821 }
1822
1823 void ProgramCompiler::LegacyConverter::visit(VariableDeclaration &var)
1824 {
1825         if(var.layout && !supports_interface_layouts())
1826         {
1827                 vector<Layout::Qualifier>::iterator i;
1828                 for(i=var.layout->qualifiers.begin(); (i!=var.layout->qualifiers.end() && i->identifier!="location"); ++i) ;
1829                 if(i!=var.layout->qualifiers.end())
1830                 {
1831                         unsigned location = lexical_cast<unsigned>(i->value);
1832                         if(stage->type==VERTEX && var.interface=="in")
1833                         {
1834                                 stage->locations[var.name] = location;
1835                                 var.layout->qualifiers.erase(i);
1836                         }
1837                         else if(stage->type==FRAGMENT && var.interface=="out")
1838                         {
1839                                 if(location!=0)
1840                                         static Require _req(EXT_gpu_shader4);
1841                                 stage->locations[var.name] = location;
1842                                 var.layout->qualifiers.erase(i);
1843                         }
1844
1845                         if(var.layout->qualifiers.empty())
1846                                 var.layout = 0;
1847                 }
1848         }
1849
1850         if(var.sampling=="centroid")
1851         {
1852                 if(!supports_centroid_sampling())
1853                         var.sampling = string();
1854         }
1855         else if(var.sampling=="sample")
1856         {
1857                 if(!supports_sample_sampling())
1858                         var.sampling = string();
1859         }
1860
1861         if((var.interface=="in" || var.interface=="out") && !supports_unified_interface_syntax())
1862         {
1863                 if(stage->type==FRAGMENT && var.interface=="out")
1864                 {
1865                         frag_out = &var;
1866                         remove_node = true;
1867                 }
1868         }
1869
1870         TraversingVisitor::visit(var);
1871 }
1872
1873 bool ProgramCompiler::LegacyConverter::supports_interface_blocks(const string &iface) const
1874 {
1875         if(target_api==OPENGL_ES2)
1876         {
1877                 if(iface=="uniform")
1878                         return check_version(Version(3, 0));
1879                 else
1880                         return check_version(Version(3, 20));
1881         }
1882         else
1883                 return check_version(Version(1, 50));
1884 }
1885
1886 void ProgramCompiler::LegacyConverter::visit(InterfaceBlock &iface)
1887 {
1888         if(!supports_interface_blocks(iface.interface))
1889                 flatten_block(iface.members);
1890 }
1891
1892 } // namespace GL
1893 } // namespace Msp