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