source/programcompiler.cpp

   1 #include <msp/core/algorithm.h>
   2 #include <msp/core/raii.h>
   3 #include <msp/gl/extensions/arb_explicit_attrib_location.h>
   4 #include <msp/gl/extensions/arb_gpu_shader5.h>
   5 #include <msp/gl/extensions/arb_uniform_buffer_object.h>
   6 #include <msp/gl/extensions/ext_gpu_shader4.h>
   7 #include <msp/gl/extensions/ext_texture_array.h>
   8 #include <msp/strings/format.h>
   9 #include <msp/strings/regex.h>
  10 #include <msp/strings/utils.h>
  11 #include "error.h"
  12 #include "program.h"
  13 #include "programcompiler.h"
  14 #include "resources.h"
  15 #include "shader.h"
  16
  17 #undef interface
  18
  19 using namespace std;
  20
  21 namespace {
  22
  23 const char builtins_src[] =
  24         "#pragma MSP stage(vertex)\n"
  25         "out gl_PerVertex {\n"
  26         "  vec4 gl_Position;\n"
  27         "  float gl_ClipDistance[];\n"
  28         "};\n"
  29         "#pragma MSP stage(geometry)\n"
  30         "in gl_PerVertex {\n"
  31         "  vec4 gl_Position;\n"
  32         "  float gl_ClipDistance[];\n"
  33         "} gl_in[];\n"
  34         "out gl_PerVertex {\n"
  35         "  vec4 gl_Position;\n"
  36         "  float gl_ClipDistance[];\n"
  37         "};\n";
  38
  39 }
  40
  41 namespace Msp {
  42 namespace GL {
  43
  44 using namespace ProgramSyntax;
  45
  46 ProgramCompiler::ProgramCompiler():
  47         resources(0),
  48         module(0)
  49 { }
  50
  51 ProgramCompiler::~ProgramCompiler()
  52 {
  53         delete module;
  54 }
  55
  56 void ProgramCompiler::compile(const string &source, const string &src_name)
  57 {
  58         resources = 0;
  59         delete module;
  60         module = new Module();
  61         ProgramParser parser;
  62         imported_names.push_back(src_name);
  63         append_module(parser.parse(source, src_name, 1));
  64         process();
  65 }
  66
  67 void ProgramCompiler::compile(IO::Base &io, Resources *res, const string &src_name)
  68 {
  69         resources = res;
  70         delete module;
  71         module = new Module();
  72         ProgramParser parser;
  73         imported_names.push_back(src_name);
  74         append_module(parser.parse(io, src_name, 1));
  75         process();
  76 }
  77
  78 void ProgramCompiler::compile(IO::Base &io, const string &src_name)
  79 {
  80         compile(io, 0, src_name);
  81 }
  82
  83 void ProgramCompiler::add_shaders(Program &program)
  84 {
  85         if(!module)
  86                 throw invalid_operation("ProgramCompiler::add_shaders");
  87
  88         try
  89         {
  90                 for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
  91                 {
  92                         if(i->type==VERTEX)
  93                         {
  94                                 program.attach_shader_owned(new VertexShader(apply<Formatter>(*i)));
  95                                 for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
  96                                         program.bind_attribute(j->second, j->first);
  97                         }
  98                         else if(i->type==GEOMETRY)
  99                                 program.attach_shader_owned(new GeometryShader(apply<Formatter>(*i)));
 100                         else if(i->type==FRAGMENT)
 101                         {
 102                                 program.attach_shader_owned(new FragmentShader(apply<Formatter>(*i)));
 103                                 if(EXT_gpu_shader4)
 104                                 {
 105                                         for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
 106                                                 program.bind_fragment_data(j->second, j->first);
 107                                 }
 108                         }
 109                 }
 110         }
 111         catch(const compile_error &e)
 112         {
 113                 static const Regex r_message("^(([0-9]+)\\(([0-9]+)\\) :|ERROR: ([0-9]+):([0-9]+):) (.*)$");
 114                 vector<string> lines = split(e.what(), '\n');
 115                 string translated;
 116                 for(vector<string>::const_iterator i=lines.begin(); i!=lines.end(); ++i)
 117                 {
 118                         RegMatch m = r_message.match(*i);
 119                         if(m)
 120                         {
 121                                 unsigned index = 0;
 122                                 unsigned line = 0;
 123                                 if(m[2])
 124                                 {
 125                                         index = lexical_cast<unsigned>(m[2].str);
 126                                         line = lexical_cast<unsigned>(m[3].str);
 127                                 }
 128                                 else if(m[4])
 129                                 {
 130                                         index = lexical_cast<unsigned>(m[4].str);
 131                                         line = lexical_cast<unsigned>(m[5].str);
 132                                 }
 133                                 const char *src = "<unknown>";
 134                                 if(index==0)
 135                                         src = "<generated>";
 136                                 else if(index-1<imported_names.size())
 137                                         src = imported_names[index-1].c_str();
 138                                 translated += format("%s:%d: %s", src, line, m[6].str);
 139                         }
 140                         else
 141                                 translated += *i;
 142                         translated += '\n';
 143                 }
 144
 145                 throw compile_error(translated);
 146         }
 147 }
 148
 149 Module *ProgramCompiler::create_builtins_module()
 150 {
 151         ProgramParser parser;
 152         Module *module = new Module(parser.parse(builtins_src, "<builtin>"));
 153         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 154         {
 155                 VariableResolver resolver;
 156                 i->content.visit(resolver);
 157                 for(map<string, VariableDeclaration *>::iterator j=i->content.variables.begin(); j!=i->content.variables.end(); ++j)
 158                         j->second->linked_declaration = j->second;
 159         }
 160         return module;
 161 }
 162
 163 Module &ProgramCompiler::get_builtins_module()
 164 {
 165         static RefPtr<Module> builtins_module = create_builtins_module();
 166         return *builtins_module;
 167 }
 168
 169 Stage *ProgramCompiler::get_builtins(StageType type)
 170 {
 171         Module &module = get_builtins_module();
 172         for(list<Stage>::iterator i=module.stages.begin(); i!=module.stages.end(); ++i)
 173                 if(i->type==type)
 174                         return &*i;
 175         return 0;
 176 }
 177
 178 void ProgramCompiler::append_module(ProgramSyntax::Module &mod)
 179 {
 180         vector<Import *> imports = apply<NodeGatherer<Import> >(mod.shared);
 181         for(vector<Import *>::iterator i=imports.begin(); i!=imports.end(); ++i)
 182                 import((*i)->module);
 183         apply<NodeRemover>(mod.shared, set<Node *>(imports.begin(), imports.end()));
 184
 185         append_stage(mod.shared);
 186         for(list<Stage>::iterator i=mod.stages.begin(); i!=mod.stages.end(); ++i)
 187                 append_stage(*i);
 188 }
 189
 190 void ProgramCompiler::append_stage(Stage &stage)
 191 {
 192         Stage *target = 0;
 193         if(stage.type==SHARED)
 194                 target = &module->shared;
 195         else
 196         {
 197                 list<Stage>::iterator i;
 198                 for(i=module->stages.begin(); (i!=module->stages.end() && i->type<stage.type); ++i) ;
 199                 if(i==module->stages.end() || i->type>stage.type)
 200                 {
 201                         list<Stage>::iterator j = module->stages.insert(i, stage.type);
 202                         if(i!=module->stages.end())
 203                                 i->previous = &*j;
 204                         i = j;
 205                         if(i!=module->stages.begin())
 206                                 i->previous = &*--j;
 207                 }
 208
 209                 target = &*i;
 210         }
 211
 212         if(stage.required_version>target->required_version)
 213                 target->required_version = stage.required_version;
 214         for(NodeList<Statement>::iterator i=stage.content.body.begin(); i!=stage.content.body.end(); ++i)
 215                 target->content.body.push_back(*i);
 216         apply<DeclarationCombiner>(*target);
 217 }
 218
 219 void ProgramCompiler::process()
 220 {
 221         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 222                 generate(*i);
 223         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); )
 224         {
 225                 if(optimize(*i))
 226                         i = module->stages.begin();
 227                 else
 228                         ++i;
 229         }
 230         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 231                 finalize(*i);
 232 }
 233
 234 void ProgramCompiler::import(const string &name)
 235 {
 236         string fn = name+".glsl";
 237         if(find(imported_names, fn)!=imported_names.end())
 238                 return;
 239         imported_names.push_back(fn);
 240
 241         RefPtr<IO::Seekable> io = (resources ? resources->open_raw(fn) : Resources::get_builtins().open(fn));
 242         if(!io)
 243                 throw runtime_error(format("module %s not found", name));
 244         ProgramParser import_parser;
 245         append_module(import_parser.parse(*io, fn, imported_names.size()));
 246 }
 247
 248 void ProgramCompiler::generate(Stage &stage)
 249 {
 250         if(module->shared.required_version>stage.required_version)
 251                 stage.required_version = module->shared.required_version;
 252         inject_block(stage.content, module->shared.content);
 253
 254         apply<DeclarationReorderer>(stage);
 255         apply<FunctionResolver>(stage);
 256         apply<VariableResolver>(stage);
 257         apply<InterfaceGenerator>(stage);
 258         apply<VariableResolver>(stage);
 259         apply<DeclarationReorderer>(stage);
 260         apply<FunctionResolver>(stage);
 261         apply<LegacyConverter>(stage);
 262 }
 263
 264 bool ProgramCompiler::optimize(Stage &stage)
 265 {
 266         apply<ConstantConditionEliminator>(stage);
 267
 268         set<FunctionDeclaration *> inlineable = apply<InlineableFunctionLocator>(stage);
 269         apply<FunctionInliner>(stage, inlineable);
 270
 271         set<Node *> unused = apply<UnusedVariableLocator>(stage);
 272         set<Node *> unused2 = apply<UnusedFunctionLocator>(stage);
 273         unused.insert(unused2.begin(), unused2.end());
 274         apply<NodeRemover>(stage, unused);
 275
 276         return !unused.empty();
 277 }
 278
 279 void ProgramCompiler::finalize(Stage &stage)
 280 {
 281         if(get_gl_api()==OPENGL_ES2)
 282                 apply<DefaultPrecisionGenerator>(stage);
 283         else
 284                 apply<PrecisionRemover>(stage);
 285 }
 286
 287 void ProgramCompiler::inject_block(Block &target, const Block &source)
 288 {
 289         NodeList<Statement>::iterator insert_point = target.body.begin();
 290         for(NodeList<Statement>::const_iterator i=source.body.begin(); i!=source.body.end(); ++i)
 291                 target.body.insert(insert_point, (*i)->clone());
 292 }
 293
 294 template<typename T>
 295 typename T::ResultType ProgramCompiler::apply(Stage &stage)
 296 {
 297         T visitor;
 298         visitor.apply(stage);
 299         return visitor.get_result();
 300 }
 301
 302 template<typename T, typename A>
 303 typename T::ResultType ProgramCompiler::apply(Stage &stage, const A &arg)
 304 {
 305         T visitor(arg);
 306         visitor.apply(stage);
 307         return visitor.get_result();
 308 }
 309
 310
 311 ProgramCompiler::Visitor::Visitor():
 312         stage(0)
 313 { }
 314
 315 void ProgramCompiler::Visitor::apply(Stage &s)
 316 {
 317         SetForScope<Stage *> set(stage, &s);
 318         stage->content.visit(*this);
 319 }
 320
 321
 322 ProgramCompiler::BlockModifier::BlockModifier():
 323         remove_node(false)
 324 { }
 325
 326 void ProgramCompiler::BlockModifier::flatten_block(Block &block)
 327 {
 328         insert_nodes.insert(insert_nodes.end(), block.body.begin(), block.body.end());
 329         remove_node = true;
 330 }
 331
 332 void ProgramCompiler::BlockModifier::apply_and_increment(Block &block, NodeList<Statement>::iterator &i)
 333 {
 334         block.body.insert(i, insert_nodes.begin(), insert_nodes.end());
 335         insert_nodes.clear();
 336
 337         if(remove_node)
 338                 block.body.erase(i++);
 339         else
 340                 ++i;
 341         remove_node = false;
 342 }
 343
 344 void ProgramCompiler::BlockModifier::visit(Block &block)
 345 {
 346         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); )
 347         {
 348                 (*i)->visit(*this);
 349                 apply_and_increment(block, i);
 350         }
 351 }
 352
 353
 354 ProgramCompiler::Formatter::Formatter():
 355         source_line(1),
 356         indent(0),
 357         parameter_list(false)
 358 { }
 359
 360 void ProgramCompiler::Formatter::apply(ProgramSyntax::Stage &s)
 361 {
 362         GLApi api = get_gl_api();
 363         const Version &ver = s.required_version;
 364
 365         if(ver)
 366         {
 367                 append(format("#version %d%02d", ver.major, ver.minor));
 368                 if(api==OPENGL_ES2 && ver>=Version(3, 0))
 369                         append(" es");
 370                 formatted += '\n';
 371         }
 372
 373         for(vector<const Extension *>::const_iterator i=s.required_extensions.begin(); i!=s.required_extensions.end(); ++i)
 374                 append(format("#extension %s: require\n", (*i)->get_name()));
 375         if(!s.required_extensions.empty())
 376                 formatted += '\n';
 377
 378         Visitor::apply(s);
 379 }
 380
 381 void ProgramCompiler::Formatter::append(const string &text)
 382 {
 383         formatted += text;
 384         for(string::const_iterator i=text.begin(); i!=text.end(); ++i)
 385                 if(*i=='\n')
 386                         ++source_line;
 387 }
 388
 389 void ProgramCompiler::Formatter::append(char c)
 390 {
 391         formatted += c;
 392         if(c=='\n')
 393                 ++source_line;
 394 }
 395
 396 void ProgramCompiler::Formatter::set_source(unsigned index, unsigned line)
 397 {
 398         if(index!=source_index || (index && line!=source_line))
 399         {
 400                 if(index==source_index && line==source_line+1)
 401                         formatted += '\n';
 402                 else
 403                 {
 404                         unsigned l = line;
 405                         if(stage->required_version<Version(3, 30))
 406                                 --l;
 407                         formatted += format("#line %d %d\n", l, index);
 408                 }
 409         }
 410         source_index = index;
 411         source_line = line;
 412 }
 413
 414 void ProgramCompiler::Formatter::visit(Literal &literal)
 415 {
 416         append(literal.token);
 417 }
 418
 419 void ProgramCompiler::Formatter::visit(ParenthesizedExpression &parexpr)
 420 {
 421         append('(');
 422         parexpr.expression->visit(*this);
 423         append(')');
 424 }
 425
 426 void ProgramCompiler::Formatter::visit(VariableReference &var)
 427 {
 428         append(var.name);
 429 }
 430
 431 void ProgramCompiler::Formatter::visit(MemberAccess &memacc)
 432 {
 433         memacc.left->visit(*this);
 434         append(format(".%s", memacc.member));
 435 }
 436
 437 void ProgramCompiler::Formatter::visit(UnaryExpression &unary)
 438 {
 439         if(unary.prefix)
 440                 append(unary.oper);
 441         unary.expression->visit(*this);
 442         if(!unary.prefix)
 443                 append(unary.oper);
 444 }
 445
 446 void ProgramCompiler::Formatter::visit(BinaryExpression &binary)
 447 {
 448         binary.left->visit(*this);
 449         append(binary.oper);
 450         binary.right->visit(*this);
 451         append(binary.after);
 452 }
 453
 454 void ProgramCompiler::Formatter::visit(Assignment &assign)
 455 {
 456         assign.left->visit(*this);
 457         append(format(" %s ", assign.oper));
 458         assign.right->visit(*this);
 459 }
 460
 461 void ProgramCompiler::Formatter::visit(FunctionCall &call)
 462 {
 463         append(format("%s(", call.name));
 464         for(NodeArray<Expression>::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
 465         {
 466                 if(i!=call.arguments.begin())
 467                         append(", ");
 468                 (*i)->visit(*this);
 469         }
 470         append(')');
 471 }
 472
 473 void ProgramCompiler::Formatter::visit(ExpressionStatement &expr)
 474 {
 475         expr.expression->visit(*this);
 476         append(';');
 477 }
 478
 479 void ProgramCompiler::Formatter::visit(Block &block)
 480 {
 481         unsigned brace_indent = indent;
 482         bool use_braces = (block.use_braces || (indent && block.body.size()!=1));
 483         if(use_braces)
 484                 append(format("%s{\n", string(brace_indent*2, ' ')));
 485
 486         SetForScope<unsigned> set(indent, indent+(indent>0 || use_braces));
 487         string spaces(indent*2, ' ');
 488         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 489         {
 490                 if(i!=block.body.begin())
 491                         append('\n');
 492                 set_source((*i)->source, (*i)->line);
 493                 append(spaces);
 494                 (*i)->visit(*this);
 495         }
 496
 497         if(use_braces)
 498                 append(format("\n%s}", string(brace_indent*2, ' ')));
 499 }
 500
 501 void ProgramCompiler::Formatter::visit(Import &import)
 502 {
 503         append(format("import %s;", import.module));
 504 }
 505
 506 void ProgramCompiler::Formatter::visit(Precision &prec)
 507 {
 508         append(format("precision %s %s;", prec.precision, prec.type));
 509 }
 510
 511 void ProgramCompiler::Formatter::visit(Layout &layout)
 512 {
 513         append("layout(");
 514         for(vector<Layout::Qualifier>::const_iterator i=layout.qualifiers.begin(); i!=layout.qualifiers.end(); ++i)
 515         {
 516                 if(i!=layout.qualifiers.begin())
 517                         append(", ");
 518                 append(i->identifier);
 519                 if(!i->value.empty())
 520                         append(format("=%s", i->value));
 521         }
 522         append(')');
 523 }
 524
 525 void ProgramCompiler::Formatter::visit(InterfaceLayout &layout)
 526 {
 527         layout.layout.visit(*this);
 528         append(format(" %s;", layout.interface));
 529 }
 530
 531 void ProgramCompiler::Formatter::visit(StructDeclaration &strct)
 532 {
 533         append(format("struct %s\n", strct.name));
 534         strct.members.visit(*this);
 535         append(';');
 536 }
 537
 538 void ProgramCompiler::Formatter::visit(VariableDeclaration &var)
 539 {
 540         if(var.layout)
 541         {
 542                 var.layout->visit(*this);
 543                 append(' ');
 544         }
 545         if(var.constant)
 546                 append("const ");
 547         if(!var.interpolation.empty())
 548                 append(format("%s ", var.interpolation));
 549         if(!var.sampling.empty())
 550                 append(format("%s ", var.sampling));
 551         if(!var.interface.empty() && var.interface!=block_interface)
 552         {
 553                 string interface = var.interface;
 554                 if(stage->required_version<Version(1, 30))
 555                 {
 556                         if(stage->type==VERTEX && var.interface=="in")
 557                                 interface = "attribute";
 558                         else if((stage->type==VERTEX && var.interface=="out") || (stage->type==FRAGMENT && var.interface=="in"))
 559                                 interface = "varying";
 560                 }
 561                 append(format("%s ", interface));
 562         }
 563         if(!var.precision.empty())
 564                 append(format("%s ", var.precision));
 565         append(format("%s %s", var.type, var.name));
 566         if(var.array)
 567         {
 568                 append('[');
 569                 if(var.array_size)
 570                         var.array_size->visit(*this);
 571                 append(']');
 572         }
 573         if(var.init_expression)
 574         {
 575                 append(" = ");
 576                 var.init_expression->visit(*this);
 577         }
 578         if(!parameter_list)
 579                 append(';');
 580 }
 581
 582 void ProgramCompiler::Formatter::visit(InterfaceBlock &iface)
 583 {
 584         SetForScope<string> set(block_interface, iface.interface);
 585         append(format("%s %s\n", iface.interface, iface.name));
 586         iface.members.visit(*this);
 587         append(';');
 588 }
 589
 590 void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 591 {
 592         append(format("%s %s(", func.return_type, func.name));
 593         for(NodeArray<VariableDeclaration>::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 594         {
 595                 if(i!=func.parameters.begin())
 596                         append(", ");
 597                 SetFlag set(parameter_list);
 598                 (*i)->visit(*this);
 599         }
 600         append(')');
 601         if(func.definition==&func)
 602         {
 603                 append('\n');
 604                 func.body.visit(*this);
 605         }
 606         else
 607                 append(';');
 608 }
 609
 610 void ProgramCompiler::Formatter::visit(Conditional &cond)
 611 {
 612         append("if(");
 613         cond.condition->visit(*this);
 614         append(")\n");
 615
 616         cond.body.visit(*this);
 617         if(!cond.else_body.body.empty())
 618         {
 619                 Conditional *else_cond = dynamic_cast<Conditional *>(cond.else_body.body.front().get());
 620                 if(cond.else_body.body.size()==1 && else_cond)
 621                 {
 622                         append('\n');
 623                         set_source(else_cond->source, else_cond->line);
 624                         append(format("%selse ", string(indent*2, ' ')));
 625                         else_cond->visit(*this);
 626                 }
 627                 else
 628                 {
 629                         append(format("\n%selse\n", string(indent*2, ' ')));
 630                         cond.else_body.visit(*this);
 631                 }
 632         }
 633 }
 634
 635 void ProgramCompiler::Formatter::visit(Iteration &iter)
 636 {
 637         if(!iter.init_statement && iter.condition && !iter.loop_expression)
 638         {
 639                 append("while(");
 640                 iter.condition->visit(*this);
 641                 append(')');
 642         }
 643         else
 644         {
 645                 append("for(");
 646                 if(iter.init_statement)
 647                         iter.init_statement->visit(*this);
 648                 else
 649                         append(';');
 650                 if(iter.condition)
 651                 {
 652                         append(' ');
 653                         iter.condition->visit(*this);
 654                 }
 655                 append(';');
 656                 if(iter.loop_expression)
 657                 {
 658                         append(' ');
 659                         iter.loop_expression->visit(*this);
 660                 }
 661                 append(')');
 662         }
 663
 664         if(iter.body.body.empty())
 665                 append(" { }");
 666         else
 667         {
 668                 append('\n');
 669                 iter.body.visit(*this);
 670         }
 671 }
 672
 673 void ProgramCompiler::Formatter::visit(Return &ret)
 674 {
 675         append("return");
 676         if(ret.expression)
 677         {
 678                 append(' ');
 679                 ret.expression->visit(*this);
 680         }
 681         append(';');
 682 }
 683
 684 void ProgramCompiler::Formatter::visit(Jump &jump)
 685 {
 686         append(jump.keyword);
 687         append(';');
 688 }
 689
 690
 691 ProgramCompiler::DeclarationCombiner::DeclarationCombiner():
 692         toplevel(true)
 693 { }
 694
 695 void ProgramCompiler::DeclarationCombiner::visit(Block &block)
 696 {
 697         if(!toplevel)
 698                 return;
 699
 700         SetForScope<bool> set(toplevel, false);
 701         BlockModifier::visit(block);
 702 }
 703
 704 void ProgramCompiler::DeclarationCombiner::visit(FunctionDeclaration &func)
 705 {
 706         vector<FunctionDeclaration *> &decls = functions[func.name];
 707         if(func.definition)
 708         {
 709                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 710                 {
 711                         (*i)->definition = func.definition;
 712                         (*i)->body.body.clear();
 713                 }
 714         }
 715         decls.push_back(&func);
 716 }
 717
 718 void ProgramCompiler::DeclarationCombiner::visit(VariableDeclaration &var)
 719 {
 720         VariableDeclaration *&ptr = variables[var.name];
 721         if(ptr)
 722         {
 723                 ptr->type = var.type;
 724                 if(var.init_expression)
 725                         ptr->init_expression = var.init_expression;
 726                 if(var.layout)
 727                 {
 728                         if(ptr->layout)
 729                         {
 730                                 for(vector<Layout::Qualifier>::iterator i=var.layout->qualifiers.begin(); i!=var.layout->qualifiers.end(); ++i)
 731                                 {
 732                                         bool found = false;
 733                                         for(vector<Layout::Qualifier>::iterator j=ptr->layout->qualifiers.begin(); (!found && j!=ptr->layout->qualifiers.end()); ++j)
 734                                                 if(j->identifier==i->identifier)
 735                                                 {
 736                                                         j->value = i->value;
 737                                                         found = true;
 738                                                 }
 739
 740                                         if(!found)
 741                                                 ptr->layout->qualifiers.push_back(*i);
 742                                 }
 743                         }
 744                         else
 745                                 ptr->layout = var.layout;
 746                 }
 747                 remove_node = true;
 748         }
 749         else
 750                 ptr = &var;
 751 }
 752
 753
 754 ProgramCompiler::VariableResolver::VariableResolver():
 755         anonymous(false),
 756         record_target(false),
 757         assignment_target(0),
 758         self_referencing(false)
 759 { }
 760
 761 void ProgramCompiler::VariableResolver::apply(Stage &s)
 762 {
 763         SetForScope<Stage *> set(stage, &s);
 764         Stage *builtins = get_builtins(stage->type);
 765         if(builtins)
 766                 blocks.push_back(&builtins->content);
 767         stage->content.visit(*this);
 768         if(builtins)
 769                 blocks.pop_back();
 770 }
 771
 772 void ProgramCompiler::VariableResolver::visit(Block &block)
 773 {
 774         blocks.push_back(&block);
 775         block.variables.clear();
 776         TraversingVisitor::visit(block);
 777         blocks.pop_back();
 778 }
 779
 780 void ProgramCompiler::VariableResolver::visit(VariableReference &var)
 781 {
 782         var.declaration = 0;
 783         type = 0;
 784         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 785         {
 786                 --i;
 787                 map<string, VariableDeclaration *>::iterator j = (*i)->variables.find(var.name);
 788                 if(j!=(*i)->variables.end())
 789                 {
 790                         var.declaration = j->second;
 791                         type = j->second->type_declaration;
 792                         break;
 793                 }
 794         }
 795
 796         if(record_target)
 797         {
 798                 if(assignment_target)
 799                 {
 800                         record_target = false;
 801                         assignment_target = 0;
 802                 }
 803                 else
 804                         assignment_target = var.declaration;
 805         }
 806         else if(var.declaration && var.declaration==assignment_target)
 807                 self_referencing = true;
 808 }
 809
 810 void ProgramCompiler::VariableResolver::visit(MemberAccess &memacc)
 811 {
 812         type = 0;
 813         TraversingVisitor::visit(memacc);
 814         memacc.declaration = 0;
 815         if(type)
 816         {
 817                 map<string, VariableDeclaration *>::iterator i = type->members.variables.find(memacc.member);
 818                 if(i!=type->members.variables.end())
 819                 {
 820                         memacc.declaration = i->second;
 821                         type = i->second->type_declaration;
 822                 }
 823                 else
 824                         type = 0;
 825         }
 826 }
 827
 828 void ProgramCompiler::VariableResolver::visit(BinaryExpression &binary)
 829 {
 830         if(binary.oper=="[")
 831         {
 832                 {
 833                         SetForScope<bool> set(record_target, false);
 834                         binary.right->visit(*this);
 835                 }
 836                 type = 0;
 837                 binary.left->visit(*this);
 838         }
 839         else
 840         {
 841                 TraversingVisitor::visit(binary);
 842                 type = 0;
 843         }
 844 }
 845
 846 void ProgramCompiler::VariableResolver::visit(Assignment &assign)
 847 {
 848         {
 849                 SetFlag set(record_target);
 850                 assignment_target = 0;
 851                 assign.left->visit(*this);
 852         }
 853
 854         self_referencing = false;
 855         assign.right->visit(*this);
 856
 857         assign.self_referencing = (self_referencing || assign.oper!="=");
 858         assign.target_declaration = assignment_target;
 859 }
 860
 861 void ProgramCompiler::VariableResolver::visit(StructDeclaration &strct)
 862 {
 863         TraversingVisitor::visit(strct);
 864         blocks.back()->types[strct.name] = &strct;
 865 }
 866
 867 void ProgramCompiler::VariableResolver::visit(VariableDeclaration &var)
 868 {
 869         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 870         {
 871                 --i;
 872                 map<string, StructDeclaration *>::iterator j = (*i)->types.find(var.type);
 873                 if(j!=(*i)->types.end())
 874                         var.type_declaration = j->second;
 875         }
 876
 877         if(!block_interface.empty() && var.interface.empty())
 878                 var.interface = block_interface;
 879
 880         TraversingVisitor::visit(var);
 881         blocks.back()->variables[var.name] = &var;
 882         if(anonymous && blocks.size()>1)
 883                 blocks[blocks.size()-2]->variables[var.name] = &var;
 884 }
 885
 886 void ProgramCompiler::VariableResolver::visit(InterfaceBlock &iface)
 887 {
 888         SetFlag set(anonymous);
 889         SetForScope<string> set2(block_interface, iface.interface);
 890         TraversingVisitor::visit(iface);
 891 }
 892
 893
 894 void ProgramCompiler::FunctionResolver::visit(FunctionCall &call)
 895 {
 896         map<string, vector<FunctionDeclaration *> >::iterator i = functions.find(call.name);
 897         if(i!=functions.end())
 898                 call.declaration = i->second.back();
 899
 900         TraversingVisitor::visit(call);
 901 }
 902
 903 void ProgramCompiler::FunctionResolver::visit(FunctionDeclaration &func)
 904 {
 905         vector<FunctionDeclaration *> &decls = functions[func.name];
 906         if(func.definition)
 907         {
 908                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 909                         (*i)->definition = func.definition;
 910                 decls.clear();
 911                 decls.push_back(&func);
 912         }
 913         else if(!decls.empty() && decls.back()->definition)
 914                 func.definition = decls.back()->definition;
 915         else
 916                 decls.push_back(&func);
 917
 918         TraversingVisitor::visit(func);
 919 }
 920
 921
 922 ProgramCompiler::InterfaceGenerator::InterfaceGenerator():
 923         scope_level(0)
 924 { }
 925
 926 string ProgramCompiler::InterfaceGenerator::get_out_prefix(StageType type)
 927 {
 928         if(type==VERTEX)
 929                 return "_vs_out_";
 930         else if(type==GEOMETRY)
 931                 return "_gs_out_";
 932         else
 933                 return string();
 934 }
 935
 936 void ProgramCompiler::InterfaceGenerator::apply(Stage &s)
 937 {
 938         SetForScope<Stage *> set(stage, &s);
 939         if(stage->previous)
 940                 in_prefix = get_out_prefix(stage->previous->type);
 941         out_prefix = get_out_prefix(stage->type);
 942         stage->content.visit(*this);
 943 }
 944
 945 void ProgramCompiler::InterfaceGenerator::visit(Block &block)
 946 {
 947         SetForScope<unsigned> set(scope_level, scope_level+1);
 948         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); )
 949         {
 950                 (*i)->visit(*this);
 951
 952                 if(scope_level==1)
 953                 {
 954                         for(map<string, RefPtr<VariableDeclaration> >::iterator j=iface_declarations.begin(); j!=iface_declarations.end(); ++j)
 955                         {
 956                                 NodeList<Statement>::iterator k = block.body.insert(i, j->second);
 957                                 (*k)->visit(*this);
 958                         }
 959                         iface_declarations.clear();
 960                 }
 961
 962                 apply_and_increment(block, i);
 963         }
 964 }
 965
 966 string ProgramCompiler::InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
 967 {
 968         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
 969         return prefix+name.substr(offset);
 970 }
 971
 972 bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
 973 {
 974         const map<string, VariableDeclaration *> &stage_vars = (iface=="in" ? stage->in_variables : stage->out_variables);
 975         if(stage_vars.count(name) || iface_declarations.count(name))
 976                 return false;
 977
 978         VariableDeclaration* iface_var = new VariableDeclaration;
 979         iface_var->sampling = var.sampling;
 980         iface_var->interface = iface;
 981         iface_var->type = var.type;
 982         iface_var->type_declaration = var.type_declaration;
 983         iface_var->name = name;
 984         if(stage->type==GEOMETRY)
 985                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
 986         else
 987                 iface_var->array = var.array;
 988         if(iface_var->array)
 989                 iface_var->array_size = var.array_size;
 990         if(iface=="in")
 991                 iface_var->linked_declaration = &var;
 992         iface_declarations[name] = iface_var;
 993
 994         return true;
 995 }
 996
 997 ExpressionStatement &ProgramCompiler::InterfaceGenerator::insert_assignment(const string &left, ProgramSyntax::Expression *right)
 998 {
 999         Assignment *assign = new Assignment;
1000         VariableReference *ref = new VariableReference;
1001         ref->name = left;
1002         assign->left = ref;
1003         assign->oper = "=";
1004         assign->right = right;
1005
1006         ExpressionStatement *stmt = new ExpressionStatement;
1007         stmt->expression = assign;
1008         stmt->visit(*this);
1009         insert_nodes.push_back(stmt);
1010
1011         return *stmt;
1012 }
1013
1014 void ProgramCompiler::InterfaceGenerator::visit(VariableReference &var)
1015 {
1016         if(var.declaration || !stage->previous)
1017                 return;
1018         if(iface_declarations.count(var.name))
1019                 return;
1020
1021         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
1022         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
1023         if(i==prev_out.end())
1024                 i = prev_out.find(in_prefix+var.name);
1025         if(i!=prev_out.end())
1026         {
1027                 generate_interface(*i->second, "in", i->second->name);
1028                 var.name = i->second->name;
1029         }
1030 }
1031
1032 void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &var)
1033 {
1034         if(var.interface=="out")
1035         {
1036                 if(scope_level==1)
1037                         stage->out_variables[var.name] = &var;
1038                 else if(generate_interface(var, "out", change_prefix(var.name, string())))
1039                 {
1040                         remove_node = true;
1041                         if(var.init_expression)
1042                         {
1043                                 ExpressionStatement &stmt = insert_assignment(var.name, var.init_expression->clone());
1044                                 stmt.source = var.source;
1045                                 stmt.line = var.line;
1046                                 return;
1047                         }
1048                 }
1049         }
1050         else if(var.interface=="in")
1051         {
1052                 stage->in_variables[var.name] = &var;
1053                 if(var.linked_declaration)
1054                         var.linked_declaration->linked_declaration = &var;
1055                 else if(stage->previous)
1056                 {
1057                         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
1058                         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
1059                         if(i!=prev_out.end())
1060                         {
1061                                 var.linked_declaration = i->second;
1062                                 i->second->linked_declaration = &var;
1063                         }
1064                 }
1065         }
1066
1067         TraversingVisitor::visit(var);
1068 }
1069
1070 void ProgramCompiler::InterfaceGenerator::visit(Passthrough &pass)
1071 {
1072         vector<VariableDeclaration *> pass_vars;
1073
1074         for(map<string, VariableDeclaration *>::const_iterator i=stage->in_variables.begin(); i!=stage->in_variables.end(); ++i)
1075                 pass_vars.push_back(i->second);
1076         for(map<string, RefPtr<VariableDeclaration> >::const_iterator i=iface_declarations.begin(); i!=iface_declarations.end(); ++i)
1077                 if(i->second->interface=="in")
1078                         pass_vars.push_back(i->second.get());
1079
1080         if(stage->previous)
1081         {
1082                 const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
1083                 for(map<string, VariableDeclaration *>::const_iterator i=prev_out.begin(); i!=prev_out.end(); ++i)
1084                 {
1085                         bool linked = false;
1086                         for(vector<VariableDeclaration *>::const_iterator j=pass_vars.begin(); (!linked && j!=pass_vars.end()); ++j)
1087                                 linked = ((*j)->linked_declaration==i->second);
1088
1089                         if(!linked && generate_interface(*i->second, "in", i->second->name))
1090                                 pass_vars.push_back(i->second);
1091                 }
1092         }
1093
1094         if(stage->type==GEOMETRY)
1095         {
1096                 VariableReference *ref = new VariableReference;
1097                 ref->name = "gl_in";
1098
1099                 BinaryExpression *subscript = new BinaryExpression;
1100                 subscript->left = ref;
1101                 subscript->oper = "[";
1102                 subscript->right = pass.subscript;
1103                 subscript->after = "]";
1104
1105                 MemberAccess *memacc = new MemberAccess;
1106                 memacc->left = subscript;
1107                 memacc->member = "gl_Position";
1108
1109                 insert_assignment("gl_Position", memacc);
1110         }
1111
1112         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
1113         {
1114                 string out_name = change_prefix((*i)->name, out_prefix);
1115                 generate_interface(**i, "out", out_name);
1116
1117                 VariableReference *ref = new VariableReference;
1118                 ref->name = (*i)->name;
1119                 if(pass.subscript)
1120                 {
1121                         BinaryExpression *subscript = new BinaryExpression;
1122                         subscript->left = ref;
1123                         subscript->oper = "[";
1124                         subscript->right = pass.subscript;
1125                         subscript->after = "]";
1126                         insert_assignment(out_name, subscript);
1127                 }
1128                 else
1129                         insert_assignment(out_name, ref);
1130         }
1131
1132         remove_node = true;
1133 }
1134
1135
1136 ProgramCompiler::DeclarationReorderer::DeclarationReorderer():
1137         scope_level(0),
1138         kind(NO_DECLARATION)
1139 { }
1140
1141 void ProgramCompiler::DeclarationReorderer::visit(FunctionCall &call)
1142 {
1143         FunctionDeclaration *def = call.declaration;
1144         if(def)
1145                 def = def->definition;
1146         if(def && !ordered_funcs.count(def))
1147                 needed_funcs.insert(def);
1148 }
1149
1150 void ProgramCompiler::DeclarationReorderer::visit(Block &block)
1151 {
1152         SetForScope<unsigned> set(scope_level, scope_level+1);
1153         if(scope_level>1)
1154                 return Visitor::visit(block);
1155
1156         NodeList<Statement>::iterator struct_insert_point = block.body.end();
1157         NodeList<Statement>::iterator variable_insert_point = block.body.end();
1158         NodeList<Statement>::iterator function_insert_point = block.body.end();
1159         unsigned unordered_func_count = 0;
1160         bool ordered_any_funcs = false;
1161
1162         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); )
1163         {
1164                 kind = NO_DECLARATION;
1165                 (*i)->visit(*this);
1166
1167                 bool moved = false;
1168                 if(kind==STRUCT && struct_insert_point!=block.body.end())
1169                 {
1170                         block.body.insert(struct_insert_point, *i);
1171                         moved = true;
1172                 }
1173                 else if(kind>STRUCT && struct_insert_point==block.body.end())
1174                         struct_insert_point = i;
1175
1176                 if(kind==VARIABLE && variable_insert_point!=block.body.end())
1177                 {
1178                         block.body.insert(variable_insert_point, *i);
1179                         moved = true;
1180                 }
1181                 else if(kind>VARIABLE && variable_insert_point==block.body.end())
1182                         variable_insert_point = i;
1183
1184                 if(kind==FUNCTION)
1185                 {
1186                         if(function_insert_point==block.body.end())
1187                                 function_insert_point = i;
1188
1189                         if(needed_funcs.empty())
1190                         {
1191                                 ordered_funcs.insert(i->get());
1192                                 if(i!=function_insert_point)
1193                                 {
1194                                         block.body.insert(function_insert_point, *i);
1195                                         moved = true;
1196                                 }
1197                                 else
1198                                         ++function_insert_point;
1199                                 ordered_any_funcs = true;
1200                         }
1201                         else
1202                                 ++unordered_func_count;
1203                 }
1204
1205                 if(moved)
1206                 {
1207                         if(function_insert_point==i)
1208                                 ++function_insert_point;
1209                         block.body.erase(i++);
1210                 }
1211                 else
1212                         ++i;
1213
1214                 if(i==block.body.end() && unordered_func_count)
1215                 {
1216                         if(!ordered_any_funcs)
1217                                 // A subset of the remaining functions forms a recursive loop
1218                                 /* TODO pick a function and move it up, adding any necessary
1219                                 declarations */
1220                                 break;
1221
1222                         i = function_insert_point;
1223                         unordered_func_count = 0;
1224                 }
1225         }
1226 }
1227
1228 void ProgramCompiler::DeclarationReorderer::visit(ProgramSyntax::VariableDeclaration &var)
1229 {
1230         Visitor::visit(var);
1231         kind = VARIABLE;
1232 }
1233
1234 void ProgramCompiler::DeclarationReorderer::visit(FunctionDeclaration &func)
1235 {
1236         needed_funcs.clear();
1237         func.body.visit(*this);
1238         needed_funcs.erase(&func);
1239         kind = FUNCTION;
1240 }
1241
1242
1243 ProgramCompiler::InlineableFunctionLocator::InlineableFunctionLocator():
1244         in_function(0)
1245 { }
1246
1247 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionCall &call)
1248 {
1249         FunctionDeclaration *def = call.declaration;
1250         if(def && def->definition!=def)
1251                 def = def->definition;
1252
1253         if(def)
1254         {
1255                 unsigned &count = refcounts[def];
1256                 ++count;
1257                 if(count>1 || def==in_function)
1258                         inlineable.erase(def);
1259         }
1260
1261         TraversingVisitor::visit(call);
1262 }
1263
1264 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionDeclaration &func)
1265 {
1266         unsigned &count = refcounts[func.definition];
1267         if(!count && func.parameters.empty())
1268                 inlineable.insert(func.definition);
1269
1270         SetForScope<FunctionDeclaration *> set(in_function, &func);
1271         TraversingVisitor::visit(func);
1272 }
1273
1274
1275 ProgramCompiler::FunctionInliner::FunctionInliner():
1276         extract_result(0)
1277 { }
1278
1279 ProgramCompiler::FunctionInliner::FunctionInliner(const set<FunctionDeclaration *> &in):
1280         inlineable(in),
1281         extract_result(0)
1282 { }
1283
1284 void ProgramCompiler::FunctionInliner::visit_and_inline(RefPtr<Expression> &ptr)
1285 {
1286         inline_result = 0;
1287         ptr->visit(*this);
1288         if(inline_result)
1289                 ptr = inline_result;
1290 }
1291
1292 void ProgramCompiler::FunctionInliner::visit(Block &block)
1293 {
1294         if(extract_result)
1295                 --extract_result;
1296
1297         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
1298         {
1299                 (*i)->visit(*this);
1300                 if(extract_result)
1301                         --extract_result;
1302         }
1303 }
1304
1305 void ProgramCompiler::FunctionInliner::visit(UnaryExpression &unary)
1306 {
1307         visit_and_inline(unary.expression);
1308         inline_result = 0;
1309 }
1310
1311 void ProgramCompiler::FunctionInliner::visit(BinaryExpression &binary)
1312 {
1313         visit_and_inline(binary.left);
1314         visit_and_inline(binary.right);
1315         inline_result = 0;
1316 }
1317
1318 void ProgramCompiler::FunctionInliner::visit(MemberAccess &memacc)
1319 {
1320         visit_and_inline(memacc.left);
1321         inline_result = 0;
1322 }
1323
1324 void ProgramCompiler::FunctionInliner::visit(FunctionCall &call)
1325 {
1326         for(NodeArray<Expression>::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
1327                 visit_and_inline(*i);
1328
1329         FunctionDeclaration *def = call.declaration;
1330         if(def && def->definition!=def)
1331                 def = def->definition;
1332
1333         if(def && inlineable.count(def))
1334         {
1335                 extract_result = 2;
1336                 def->visit(*this);
1337         }
1338         else
1339                 inline_result = 0;
1340 }
1341
1342 void ProgramCompiler::FunctionInliner::visit(VariableDeclaration &var)
1343 {
1344         if(var.init_expression)
1345                 visit_and_inline(var.init_expression);
1346         inline_result = 0;
1347 }
1348
1349 void ProgramCompiler::FunctionInliner::visit(Return &ret)
1350 {
1351         TraversingVisitor::visit(ret);
1352
1353         if(extract_result)
1354                 inline_result = ret.expression->clone();
1355 }
1356
1357
1358 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator():
1359         variable_values(0),
1360         result(0.0f),
1361         result_valid(false)
1362 { }
1363
1364 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator(const ValueMap &v):
1365         variable_values(&v),
1366         result(0.0f),
1367         result_valid(false)
1368 { }
1369
1370 void ProgramCompiler::ExpressionEvaluator::visit(Literal &literal)
1371 {
1372         if(literal.token=="true")
1373                 result = 1.0f;
1374         else if(literal.token=="false")
1375                 result = 0.0f;
1376         else
1377                 result = lexical_cast<float>(literal.token);
1378         result_valid = true;
1379 }
1380
1381 void ProgramCompiler::ExpressionEvaluator::visit(ParenthesizedExpression &parexp)
1382 {
1383         parexp.expression->visit(*this);
1384 }
1385
1386 void ProgramCompiler::ExpressionEvaluator::visit(VariableReference &var)
1387 {
1388         if(!var.declaration)
1389                 return;
1390
1391         if(variable_values)
1392         {
1393                 ValueMap::const_iterator i = variable_values->find(var.declaration);
1394                 if(i!=variable_values->end())
1395                         i->second->visit(*this);
1396         }
1397         else if(var.declaration->init_expression)
1398                 var.declaration->init_expression->visit(*this);
1399 }
1400
1401 void ProgramCompiler::ExpressionEvaluator::visit(UnaryExpression &unary)
1402 {
1403         result_valid = false;
1404         unary.expression->visit(*this);
1405         if(!result_valid)
1406                 return;
1407
1408         if(unary.oper=="!")
1409                 result = !result;
1410         else
1411                 result_valid = false;
1412 }
1413
1414 void ProgramCompiler::ExpressionEvaluator::visit(BinaryExpression &binary)
1415 {
1416         result_valid = false;
1417         binary.left->visit(*this);
1418         if(!result_valid)
1419                 return;
1420
1421         float left_result = result;
1422         result_valid = false;
1423         binary.right->visit(*this);
1424         if(!result_valid)
1425                 return;
1426
1427         if(binary.oper=="<")
1428                 result = (left_result<result);
1429         else if(binary.oper=="<=")
1430                 result = (left_result<=result);
1431         else if(binary.oper==">")
1432                 result = (left_result>result);
1433         else if(binary.oper==">=")
1434                 result = (left_result>=result);
1435         else if(binary.oper=="==")
1436                 result = (left_result==result);
1437         else if(binary.oper=="!=")
1438                 result = (left_result!=result);
1439         else if(binary.oper=="&&")
1440                 result = (left_result && result);
1441         else if(binary.oper=="||")
1442                 result = (left_result || result);
1443         else
1444                 result_valid = false;
1445 }
1446
1447
1448 ProgramCompiler::ConstantConditionEliminator::ConstantConditionEliminator():
1449         scope_level(0),
1450         record_only(false)
1451 { }
1452
1453 void ProgramCompiler::ConstantConditionEliminator::visit(Block &block)
1454 {
1455         SetForScope<unsigned> set(scope_level, scope_level+1);
1456         BlockModifier::visit(block);
1457
1458         for(map<string, VariableDeclaration *>::const_iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
1459                 variable_values.erase(i->second);
1460 }
1461
1462 void ProgramCompiler::ConstantConditionEliminator::visit(UnaryExpression &unary)
1463 {
1464         if(VariableReference *var = dynamic_cast<VariableReference *>(unary.expression.get()))
1465                 if(unary.oper=="++" || unary.oper=="--")
1466                         variable_values.erase(var->declaration);
1467 }
1468
1469 void ProgramCompiler::ConstantConditionEliminator::visit(Assignment &assign)
1470 {
1471         variable_values.erase(assign.target_declaration);
1472 }
1473
1474 void ProgramCompiler::ConstantConditionEliminator::visit(VariableDeclaration &var)
1475 {
1476         if(var.constant || scope_level>1)
1477                 variable_values[&var] = var.init_expression.get();
1478 }
1479
1480 void ProgramCompiler::ConstantConditionEliminator::visit(Conditional &cond)
1481 {
1482         if(!record_only)
1483         {
1484                 ExpressionEvaluator eval(variable_values);
1485                 cond.condition->visit(eval);
1486                 if(eval.result_valid)
1487                 {
1488                         flatten_block(eval.result ? cond.body : cond.else_body);
1489                         return;
1490                 }
1491         }
1492
1493         TraversingVisitor::visit(cond);
1494 }
1495
1496 void ProgramCompiler::ConstantConditionEliminator::visit(Iteration &iter)
1497 {
1498         if(!record_only)
1499         {
1500                 if(iter.condition)
1501                 {
1502                         /* If the loop condition is always false on the first iteration, the
1503                         entire loop can be removed */
1504                         if(iter.init_statement)
1505                                 iter.init_statement->visit(*this);
1506                         ExpressionEvaluator eval(variable_values);
1507                         iter.condition->visit(eval);
1508                         if(eval.result_valid && !eval.result)
1509                         {
1510                                 remove_node = true;
1511                                 return;
1512                         }
1513                 }
1514
1515                 /* Record all assignments that occur inside the loop body so those
1516                 variables won't be considered as constant */
1517                 SetFlag set_record(record_only);
1518                 TraversingVisitor::visit(iter);
1519         }
1520
1521         TraversingVisitor::visit(iter);
1522
1523         if(VariableDeclaration *init_decl = dynamic_cast<VariableDeclaration *>(iter.init_statement.get()))
1524                 variable_values.erase(init_decl);
1525 }
1526
1527
1528 ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
1529         aggregate(0),
1530         assignment(0),
1531         assignment_target(false),
1532         assign_to_subscript(false),
1533         global_scope(true)
1534 { }
1535
1536 void ProgramCompiler::UnusedVariableLocator::apply(Stage &s)
1537 {
1538         variables.push_back(BlockVariableMap());
1539         Visitor::apply(s);
1540         BlockVariableMap &global_variables = variables.back();
1541         for(BlockVariableMap::iterator i=global_variables.begin(); i!=global_variables.end(); ++i)
1542         {
1543                 if(i->first->interface=="out" && (s.type==FRAGMENT || i->first->linked_declaration || !i->first->name.compare(0, 3, "gl_")))
1544                         continue;
1545                 if(!i->second.referenced)
1546                 {
1547                         unused_nodes.insert(i->first);
1548                         clear_assignments(i->second, true);
1549                 }
1550         }
1551         variables.pop_back();
1552 }
1553
1554 void ProgramCompiler::UnusedVariableLocator::visit(VariableReference &var)
1555 {
1556         map<VariableDeclaration *, Node *>::iterator i = aggregates.find(var.declaration);
1557         if(i!=aggregates.end())
1558                 unused_nodes.erase(i->second);
1559
1560         if(var.declaration && !assignment_target)
1561         {
1562                 VariableInfo &var_info = variables.back()[var.declaration];
1563                 var_info.assignments.clear();
1564                 var_info.referenced = true;
1565         }
1566 }
1567
1568 void ProgramCompiler::UnusedVariableLocator::visit(MemberAccess &memacc)
1569 {
1570         TraversingVisitor::visit(memacc);
1571         unused_nodes.erase(memacc.declaration);
1572 }
1573
1574 void ProgramCompiler::UnusedVariableLocator::visit(BinaryExpression &binary)
1575 {
1576         if(binary.oper=="[")
1577         {
1578                 if(assignment_target)
1579                         assign_to_subscript = true;
1580                 binary.left->visit(*this);
1581                 SetForScope<bool> set(assignment_target, false);
1582                 binary.right->visit(*this);
1583         }
1584         else
1585                 TraversingVisitor::visit(binary);
1586 }
1587
1588 void ProgramCompiler::UnusedVariableLocator::visit(Assignment &assign)
1589 {
1590         {
1591                 assign_to_subscript = false;
1592                 SetForScope<bool> set(assignment_target, !assign.self_referencing);
1593                 assign.left->visit(*this);
1594         }
1595         assign.right->visit(*this);
1596         assignment = &assign;
1597 }
1598
1599 void ProgramCompiler::UnusedVariableLocator::record_assignment(VariableDeclaration &var, Node &node, bool chained)
1600 {
1601         VariableInfo &var_info = variables.back()[&var];
1602         if(!chained)
1603                 clear_assignments(var_info, true);
1604         var_info.assignments.push_back(&node);
1605         var_info.conditionally_assigned = false;
1606 }
1607
1608 void ProgramCompiler::UnusedVariableLocator::clear_assignments(VariableInfo &var_info, bool mark_unused)
1609 {
1610         if(mark_unused)
1611         {
1612                 for(vector<Node *>::iterator i=var_info.assignments.begin(); i!=var_info.assignments.end(); ++i)
1613                         unused_nodes.insert(*i);
1614         }
1615         var_info.assignments.clear();
1616 }
1617
1618 void ProgramCompiler::UnusedVariableLocator::visit(ExpressionStatement &expr)
1619 {
1620         assignment = 0;
1621         TraversingVisitor::visit(expr);
1622         if(assignment && assignment->target_declaration)
1623                 record_assignment(*assignment->target_declaration, expr, (assignment->self_referencing || assign_to_subscript));
1624 }
1625
1626 void ProgramCompiler::UnusedVariableLocator::visit(StructDeclaration &strct)
1627 {
1628         SetForScope<Node *> set(aggregate, &strct);
1629         unused_nodes.insert(&strct);
1630         TraversingVisitor::visit(strct);
1631 }
1632
1633 void ProgramCompiler::UnusedVariableLocator::visit(VariableDeclaration &var)
1634 {
1635         if(aggregate)
1636                 aggregates[&var] = aggregate;
1637         else
1638         {
1639                 variables.back()[&var].local = true;
1640                 if(var.init_expression)
1641                         record_assignment(var, *var.init_expression, false);
1642         }
1643         unused_nodes.erase(var.type_declaration);
1644         TraversingVisitor::visit(var);
1645 }
1646
1647 void ProgramCompiler::UnusedVariableLocator::visit(InterfaceBlock &iface)
1648 {
1649         SetForScope<Node *> set(aggregate, &iface);
1650         unused_nodes.insert(&iface);
1651         TraversingVisitor::visit(iface);
1652 }
1653
1654 void ProgramCompiler::UnusedVariableLocator::visit(FunctionDeclaration &func)
1655 {
1656         variables.push_back(BlockVariableMap());
1657
1658         {
1659                 SetForScope<bool> set(global_scope, false);
1660                 for(NodeArray<VariableDeclaration>::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1661                         (*i)->visit(*this);
1662                 func.body.visit(*this);
1663         }
1664
1665         BlockVariableMap &block_variables = variables.back();
1666         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1667                 i->second.conditionally_assigned = true;
1668         for(NodeArray<VariableDeclaration>::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1669                 block_variables[i->get()].referenced = true;
1670         merge_down_variables();
1671 }
1672
1673 void ProgramCompiler::UnusedVariableLocator::merge_down_variables()
1674 {
1675         BlockVariableMap &parent_variables = variables[variables.size()-2];
1676         BlockVariableMap &block_variables = variables.back();
1677         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1678         {
1679                 if(i->second.local)
1680                 {
1681                         if(!i->second.referenced)
1682                                 unused_nodes.insert(i->first);
1683                         clear_assignments(i->second, true);
1684                         continue;
1685                 }
1686
1687                 BlockVariableMap::iterator j = parent_variables.find(i->first);
1688                 if(j==parent_variables.end())
1689                         parent_variables.insert(*i);
1690                 else
1691                 {
1692                         if(i->second.referenced || !i->second.conditionally_assigned)
1693                                 clear_assignments(j->second, !i->second.referenced);
1694                         j->second.conditionally_assigned = i->second.conditionally_assigned;
1695                         j->second.referenced |= i->second.referenced;
1696                         j->second.assignments.insert(j->second.assignments.end(), i->second.assignments.begin(), i->second.assignments.end());
1697                 }
1698         }
1699         variables.pop_back();
1700 }
1701
1702 void ProgramCompiler::UnusedVariableLocator::visit(Conditional &cond)
1703 {
1704         cond.condition->visit(*this);
1705         variables.push_back(BlockVariableMap());
1706         cond.body.visit(*this);
1707
1708         BlockVariableMap if_variables;
1709         swap(variables.back(), if_variables);
1710         cond.else_body.visit(*this);
1711
1712         BlockVariableMap &else_variables = variables.back();
1713         for(BlockVariableMap::iterator i=else_variables.begin(); i!=else_variables.end(); ++i)
1714         {
1715                 BlockVariableMap::iterator j = if_variables.find(i->first);
1716                 if(j!=if_variables.end())
1717                 {
1718                         i->second.assignments.insert(i->second.assignments.end(), j->second.assignments.begin(), j->second.assignments.end());
1719                         i->second.conditionally_assigned |= j->second.conditionally_assigned;
1720                         if_variables.erase(j);
1721                 }
1722                 else
1723                         i->second.conditionally_assigned = true;
1724         }
1725
1726         for(BlockVariableMap::iterator i=if_variables.begin(); i!=if_variables.end(); ++i)
1727         {
1728                 i->second.conditionally_assigned = true;
1729                 else_variables.insert(*i);
1730         }
1731
1732         merge_down_variables();
1733 }
1734
1735 void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
1736 {
1737         variables.push_back(BlockVariableMap());
1738         TraversingVisitor::visit(iter);
1739
1740         BlockVariableMap &block_variables = variables.back();
1741         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1742                 if(!i->second.local && i->second.referenced)
1743                         i->second.assignments.clear();
1744
1745         merge_down_variables();
1746 }
1747
1748
1749 ProgramCompiler::UnusedVariableLocator::VariableInfo::VariableInfo():
1750         local(false),
1751         conditionally_assigned(false),
1752         referenced(false)
1753 { }
1754
1755
1756 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionCall &call)
1757 {
1758         TraversingVisitor::visit(call);
1759
1760         unused_nodes.erase(call.declaration);
1761         if(call.declaration && call.declaration->definition!=call.declaration)
1762                 used_definitions.insert(call.declaration->definition);
1763 }
1764
1765 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionDeclaration &func)
1766 {
1767         TraversingVisitor::visit(func);
1768
1769         if((func.name!="main" || func.body.body.empty()) && !used_definitions.count(&func))
1770                 unused_nodes.insert(&func);
1771 }
1772
1773
1774 ProgramCompiler::NodeRemover::NodeRemover(const set<Node *> &r):
1775         to_remove(r)
1776 { }
1777
1778 void ProgramCompiler::NodeRemover::visit(Block &block)
1779 {
1780         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); )
1781         {
1782                 (*i)->visit(*this);
1783                 if(to_remove.count(i->get()))
1784                         block.body.erase(i++);
1785                 else
1786                         ++i;
1787         }
1788 }
1789
1790 void ProgramCompiler::NodeRemover::visit(VariableDeclaration &var)
1791 {
1792         if(to_remove.count(&var))
1793         {
1794                 stage->in_variables.erase(var.name);
1795                 stage->out_variables.erase(var.name);
1796                 stage->locations.erase(var.name);
1797                 if(var.linked_declaration)
1798                         var.linked_declaration->linked_declaration = 0;
1799         }
1800         else if(var.init_expression && to_remove.count(var.init_expression.get()))
1801                 var.init_expression = 0;
1802 }
1803
1804 void ProgramCompiler::NodeRemover::visit(Iteration &iter)
1805 {
1806         if(to_remove.count(iter.init_statement.get()))
1807                 iter.init_statement = 0;
1808         TraversingVisitor::visit(iter);
1809 }
1810
1811
1812 void ProgramCompiler::PrecisionRemover::visit(Precision &)
1813 {
1814         remove_node = true;
1815 }
1816
1817 void ProgramCompiler::PrecisionRemover::visit(VariableDeclaration &var)
1818 {
1819         var.precision.clear();
1820 }
1821
1822
1823 ProgramCompiler::DefaultPrecisionGenerator::DefaultPrecisionGenerator():
1824         toplevel(true)
1825 { }
1826
1827 void ProgramCompiler::DefaultPrecisionGenerator::visit(Block &block)
1828 {
1829         if(toplevel)
1830         {
1831                 SetForScope<bool> set(toplevel, false);
1832                 BlockModifier::visit(block);
1833         }
1834         else
1835                 Visitor::visit(block);
1836 }
1837
1838 void ProgramCompiler::DefaultPrecisionGenerator::visit(Precision &prec)
1839 {
1840         have_default.insert(prec.type);
1841 }
1842
1843 void ProgramCompiler::DefaultPrecisionGenerator::visit(VariableDeclaration &var)
1844 {
1845         if(var.type_declaration)
1846                 return;
1847
1848         string type = var.type;
1849         if(!type.compare(0, 3, "vec") || !type.compare(0, 3, "mat"))
1850                 type = "float";
1851         else if(!type.compare(0, 3, "ivec") || type=="uint")
1852                 type = "int";
1853
1854         if(!have_default.count(type))
1855         {
1856                 Precision *prec = new Precision;
1857                 if(!type.compare(0, 7, "sampler"))
1858                         prec->precision = "lowp";
1859                 else if(stage->type==FRAGMENT)
1860                         prec->precision = "mediump";
1861                 else
1862                         prec->precision = "highp";
1863                 prec->type = type;
1864                 insert_nodes.push_back(prec);
1865
1866                 have_default.insert(type);
1867         }
1868 }
1869
1870
1871 ProgramCompiler::LegacyConverter::LegacyConverter():
1872         target_api(get_gl_api()),
1873         target_version(get_glsl_version()),
1874         frag_out(0)
1875 { }
1876
1877 ProgramCompiler::LegacyConverter::LegacyConverter(const Version &v):
1878         target_api(get_gl_api()),
1879         target_version(v),
1880         frag_out(0)
1881 { }
1882
1883 bool ProgramCompiler::LegacyConverter::check_version(const Version &feature_version) const
1884 {
1885         if(target_version<feature_version)
1886                 return false;
1887         else if(stage->required_version<feature_version)
1888                 stage->required_version = feature_version;
1889
1890         return true;
1891 }
1892
1893 bool ProgramCompiler::LegacyConverter::check_extension(const Extension &extension) const
1894 {
1895         if(!extension)
1896                 return false;
1897
1898         vector<const Extension *>::iterator i = find(stage->required_extensions, &extension);
1899         if(i==stage->required_extensions.end())
1900                 stage->required_extensions.push_back(&extension);
1901
1902         return true;
1903 }
1904
1905 bool ProgramCompiler::LegacyConverter::supports_unified_interface_syntax() const
1906 {
1907         if(target_api==OPENGL_ES2)
1908                 return check_version(Version(3, 0));
1909         else
1910                 return check_version(Version(1, 30));
1911 }
1912
1913 void ProgramCompiler::LegacyConverter::visit(VariableReference &var)
1914 {
1915         if(var.declaration==frag_out && !supports_unified_interface_syntax())
1916         {
1917                 var.name = "gl_FragColor";
1918                 var.declaration = 0;
1919                 type = "vec4";
1920         }
1921         else if(var.declaration)
1922                 type = var.declaration->type;
1923         else
1924                 type = string();
1925 }
1926
1927 void ProgramCompiler::LegacyConverter::visit(Assignment &assign)
1928 {
1929         TraversingVisitor::visit(assign);
1930         if(assign.target_declaration==frag_out && !supports_unified_interface_syntax())
1931                 assign.target_declaration = 0;
1932 }
1933
1934 bool ProgramCompiler::LegacyConverter::supports_unified_sampling_functions() const
1935 {
1936         if(target_api==OPENGL_ES2)
1937                 return check_version(Version(3, 0));
1938         else
1939                 return check_version(Version(1, 30));
1940 }
1941
1942 void ProgramCompiler::LegacyConverter::visit(FunctionCall &call)
1943 {
1944         if(call.name=="texture" && !call.declaration && !supports_unified_sampling_functions())
1945         {
1946                 NodeArray<Expression>::iterator i = call.arguments.begin();
1947                 if(i!=call.arguments.end())
1948                 {
1949                         (*i)->visit(*this);
1950                         if(type=="sampler1D")
1951                                 call.name = "texture1D";
1952                         else if(type=="sampler2D")
1953                                 call.name = "texture2D";
1954                         else if(type=="sampler3D")
1955                                 call.name = "texture3D";
1956                         else if(type=="samplerCube")
1957                                 call.name = "textureCube";
1958                         else if(type=="sampler1DShadow")
1959                                 call.name = "shadow1D";
1960                         else if(type=="sampler2DShadow")
1961                                 call.name = "shadow2D";
1962                         else if(type=="sampler1DArray")
1963                         {
1964                                 check_extension(EXT_texture_array);
1965                                 call.name = "texture1DArray";
1966                         }
1967                         else if(type=="sampler2DArray")
1968                         {
1969                                 check_extension(EXT_texture_array);
1970                                 call.name = "texture2DArray";
1971                         }
1972                         else if(type=="sampler1DArrayShadow")
1973                         {
1974                                 check_extension(EXT_texture_array);
1975                                 call.name = "shadow1DArray";
1976                         }
1977                         else if(type=="sampler2DArrayShadow")
1978                         {
1979                                 check_extension(EXT_texture_array);
1980                                 call.name = "shadow2DArray";
1981                         }
1982
1983                         for(; i!=call.arguments.end(); ++i)
1984                                 (*i)->visit(*this);
1985                 }
1986         }
1987         else
1988                 TraversingVisitor::visit(call);
1989 }
1990
1991 bool ProgramCompiler::LegacyConverter::supports_interface_layouts() const
1992 {
1993         if(target_api==OPENGL_ES2)
1994                 return check_version(Version(3, 0));
1995         else if(check_version(Version(3, 30)))
1996                 return true;
1997         else
1998                 return check_extension(ARB_explicit_attrib_location);
1999 }
2000
2001 bool ProgramCompiler::LegacyConverter::supports_centroid_sampling() const
2002 {
2003         if(target_api==OPENGL_ES2)
2004                 return check_version(Version(3, 0));
2005         else if(check_version(Version(1, 20)))
2006                 return true;
2007         else
2008                 return check_extension(EXT_gpu_shader4);
2009 }
2010
2011 bool ProgramCompiler::LegacyConverter::supports_sample_sampling() const
2012 {
2013         if(target_api==OPENGL_ES2)
2014                 return check_version(Version(3, 20));
2015         else if(check_version(Version(4, 0)))
2016                 return true;
2017         else
2018                 return check_extension(ARB_gpu_shader5);
2019 }
2020
2021 void ProgramCompiler::LegacyConverter::visit(VariableDeclaration &var)
2022 {
2023         if(var.layout && !supports_interface_layouts())
2024         {
2025                 vector<Layout::Qualifier>::iterator i;
2026                 for(i=var.layout->qualifiers.begin(); (i!=var.layout->qualifiers.end() && i->identifier!="location"); ++i) ;
2027                 if(i!=var.layout->qualifiers.end())
2028                 {
2029                         unsigned location = lexical_cast<unsigned>(i->value);
2030                         if(stage->type==VERTEX && var.interface=="in")
2031                         {
2032                                 stage->locations[var.name] = location;
2033                                 var.layout->qualifiers.erase(i);
2034                         }
2035                         else if(stage->type==FRAGMENT && var.interface=="out")
2036                         {
2037                                 if(location!=0)
2038                                         static Require _req(EXT_gpu_shader4);
2039                                 stage->locations[var.name] = location;
2040                                 var.layout->qualifiers.erase(i);
2041                         }
2042
2043                         if(var.layout->qualifiers.empty())
2044                                 var.layout = 0;
2045                 }
2046         }
2047
2048         if(var.sampling=="centroid")
2049         {
2050                 if(!supports_centroid_sampling())
2051                         var.sampling = string();
2052         }
2053         else if(var.sampling=="sample")
2054         {
2055                 if(!supports_sample_sampling())
2056                         var.sampling = string();
2057         }
2058
2059         if((var.interface=="in" || var.interface=="out") && !supports_unified_interface_syntax())
2060         {
2061                 if(stage->type==FRAGMENT && var.interface=="out")
2062                 {
2063                         frag_out = &var;
2064                         remove_node = true;
2065                 }
2066         }
2067
2068         TraversingVisitor::visit(var);
2069 }
2070
2071 bool ProgramCompiler::LegacyConverter::supports_interface_blocks(const string &iface) const
2072 {
2073         if(target_api==OPENGL_ES2)
2074         {
2075                 if(iface=="uniform")
2076                         return check_version(Version(3, 0));
2077                 else
2078                         return check_version(Version(3, 20));
2079         }
2080         else if(check_version(Version(1, 50)))
2081                 return true;
2082         else if(iface=="uniform")
2083                 return check_extension(ARB_uniform_buffer_object);
2084         else
2085                 return false;
2086 }
2087
2088 void ProgramCompiler::LegacyConverter::visit(InterfaceBlock &iface)
2089 {
2090         if(!supports_interface_blocks(iface.interface))
2091                 flatten_block(iface.members);
2092 }
2093
2094 } // namespace GL
2095 } // namespace Msp