source/programcompiler.cpp

   1 #include <msp/core/raii.h>
   2 #include <msp/strings/format.h>
   3 #include <msp/strings/utils.h>
   4 #include "error.h"
   5 #include "program.h"
   6 #include "programcompiler.h"
   7 #include "shader.h"
   8
   9 using namespace std;
  10
  11 namespace {
  12
  13 const char builtins_src[] =
  14         "////// vertex\n"
  15         "out gl_PerVertex {\n"
  16         "  vec4 gl_Position;\n"
  17         "  float gl_ClipDistance[];\n"
  18         "};"
  19         "////// geometry\n"
  20         "in gl_PerVertex {\n"
  21         "  vec4 gl_Position;\n"
  22         "  float gl_ClipDistance[];\n"
  23         "} gl_in[];\n"
  24         "out gl_PerVertex {\n"
  25         "  vec4 gl_Position;\n"
  26         "  float gl_ClipDistance[];\n"
  27         "};\n";
  28
  29 }
  30
  31 namespace Msp {
  32 namespace GL {
  33
  34 using namespace ProgramSyntax;
  35
  36 ProgramCompiler::ProgramCompiler():
  37         module(0)
  38 { }
  39
  40 void ProgramCompiler::compile(const string &source)
  41 {
  42         module = &parser.parse(source);
  43         process();
  44 }
  45
  46 void ProgramCompiler::compile(IO::Base &io)
  47 {
  48         module = &parser.parse(io);
  49         process();
  50 }
  51
  52 void ProgramCompiler::add_shaders(Program &program)
  53 {
  54         if(!module)
  55                 throw invalid_operation("ProgramCompiler::add_shaders");
  56
  57         string head = "#version 150\n";
  58         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
  59         {
  60                 if(i->type==VERTEX)
  61                         program.attach_shader_owned(new VertexShader(head+create_source(*i)));
  62                 else if(i->type==GEOMETRY)
  63                         program.attach_shader_owned(new GeometryShader(head+create_source(*i)));
  64                 else if(i->type==FRAGMENT)
  65                         program.attach_shader_owned(new FragmentShader(head+create_source(*i)));
  66         }
  67
  68         program.bind_attribute(VERTEX4, "vertex");
  69         program.bind_attribute(NORMAL3, "normal");
  70         program.bind_attribute(COLOR4_FLOAT, "color");
  71         program.bind_attribute(TEXCOORD4, "texcoord");
  72 }
  73
  74 Module *ProgramCompiler::create_builtins_module()
  75 {
  76         ProgramParser parser;
  77         Module *module = new Module(parser.parse(builtins_src));
  78         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
  79         {
  80                 VariableResolver resolver;
  81                 i->content.visit(resolver);
  82                 for(map<string, VariableDeclaration *>::iterator j=i->content.variables.begin(); j!=i->content.variables.end(); ++j)
  83                         j->second->linked_declaration = j->second;
  84         }
  85         return module;
  86 }
  87
  88 Module &ProgramCompiler::get_builtins_module()
  89 {
  90         static RefPtr<Module> builtins_module = create_builtins_module();
  91         return *builtins_module;
  92 }
  93
  94 Stage *ProgramCompiler::get_builtins(StageType type)
  95 {
  96         Module &module = get_builtins_module();
  97         for(list<Stage>::iterator i=module.stages.begin(); i!=module.stages.end(); ++i)
  98                 if(i->type==type)
  99                         return &*i;
 100         return 0;
 101 }
 102
 103 void ProgramCompiler::process()
 104 {
 105         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
 106                 generate(*i);
 107         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); )
 108         {
 109                 if(optimize(*i))
 110                         i = module->stages.begin();
 111                 else
 112                         ++i;
 113         }
 114 }
 115
 116 void ProgramCompiler::generate(Stage &stage)
 117 {
 118         inject_block(stage.content, module->shared.content);
 119
 120         apply<VariableResolver>(stage);
 121         apply<InterfaceGenerator>(stage);
 122         apply<VariableResolver>(stage);
 123         apply<VariableRenamer>(stage);
 124 }
 125
 126 bool ProgramCompiler::optimize(Stage &stage)
 127 {
 128         UnusedVariableLocator unused_locator;
 129         unused_locator.apply(stage);
 130
 131         NodeRemover remover;
 132         remover.to_remove = unused_locator.unused_nodes;
 133         remover.apply(stage);
 134
 135         return !unused_locator.unused_nodes.empty();
 136 }
 137
 138 void ProgramCompiler::inject_block(Block &target, const Block &source)
 139 {
 140         list<NodePtr<Node> >::iterator insert_point = target.body.begin();
 141         for(list<NodePtr<Node> >::const_iterator i=source.body.begin(); i!=source.body.end(); ++i)
 142                 target.body.insert(insert_point, (*i)->clone());
 143 }
 144
 145 template<typename T>
 146 void ProgramCompiler::apply(Stage &stage)
 147 {
 148         T visitor;
 149         visitor.apply(stage);
 150 }
 151
 152 string ProgramCompiler::create_source(Stage &stage)
 153 {
 154         Formatter formatter;
 155         formatter.apply(stage);
 156         return formatter.formatted;
 157 }
 158
 159
 160 ProgramCompiler::Visitor::Visitor():
 161         stage(0)
 162 { }
 163
 164 void ProgramCompiler::Visitor::apply(Stage &s)
 165 {
 166         SetForScope<Stage *> set(stage, &s);
 167         stage->content.visit(*this);
 168 }
 169
 170
 171 ProgramCompiler::Formatter::Formatter():
 172         indent(0),
 173         parameter_list(false),
 174         else_if(false)
 175 { }
 176
 177 void ProgramCompiler::Formatter::visit(Literal &literal)
 178 {
 179         formatted += literal.token;
 180 }
 181
 182 void ProgramCompiler::Formatter::visit(ParenthesizedExpression &parexpr)
 183 {
 184         formatted += '(';
 185         parexpr.expression->visit(*this);
 186         formatted += ')';
 187 }
 188
 189 void ProgramCompiler::Formatter::visit(VariableReference &var)
 190 {
 191         formatted += var.name;
 192 }
 193
 194 void ProgramCompiler::Formatter::visit(MemberAccess &memacc)
 195 {
 196         memacc.left->visit(*this);
 197         formatted += format(".%s", memacc.member);
 198 }
 199
 200 void ProgramCompiler::Formatter::visit(UnaryExpression &unary)
 201 {
 202         if(unary.prefix)
 203                 formatted += unary.oper;
 204         unary.expression->visit(*this);
 205         if(!unary.prefix)
 206                 formatted += unary.oper;
 207 }
 208
 209 void ProgramCompiler::Formatter::visit(BinaryExpression &binary)
 210 {
 211         binary.left->visit(*this);
 212         formatted += binary.oper;
 213         binary.right->visit(*this);
 214         formatted += binary.after;
 215 }
 216
 217 void ProgramCompiler::Formatter::visit(Assignment &assign)
 218 {
 219         assign.left->visit(*this);
 220         formatted += format(" %s ", assign.oper);
 221         assign.right->visit(*this);
 222 }
 223
 224 void ProgramCompiler::Formatter::visit(FunctionCall &call)
 225 {
 226         formatted += format("%s(", call.name);
 227         for(vector<NodePtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
 228         {
 229                 if(i!=call.arguments.begin())
 230                         formatted += ", ";
 231                 (*i)->visit(*this);
 232         }
 233         formatted += ')';
 234 }
 235
 236 void ProgramCompiler::Formatter::visit(ExpressionStatement &expr)
 237 {
 238         expr.expression->visit(*this);
 239         formatted += ';';
 240 }
 241
 242 void ProgramCompiler::Formatter::visit(Block &block)
 243 {
 244         if(block.use_braces)
 245         {
 246                 if(else_if)
 247                 {
 248                         formatted += '\n';
 249                         else_if = false;
 250                 }
 251                 formatted += format("%s{\n", string(indent*2, ' '));
 252         }
 253
 254         bool change_indent = (!formatted.empty() && !else_if);
 255         indent += change_indent;
 256         string spaces(indent*2, ' ');
 257         for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 258         {
 259                 if(i!=block.body.begin())
 260                         formatted += '\n';
 261                 if(!else_if)
 262                         formatted += spaces;
 263                 (*i)->visit(*this);
 264         }
 265         indent -= change_indent;
 266
 267         if(block.use_braces)
 268                 formatted += format("\n%s}", string(indent*2, ' '));
 269 }
 270
 271 void ProgramCompiler::Formatter::visit(Layout &layout)
 272 {
 273         formatted += "layout(";
 274         for(vector<Layout::Qualifier>::const_iterator i=layout.qualifiers.begin(); i!=layout.qualifiers.end(); ++i)
 275         {
 276                 if(i!=layout.qualifiers.begin())
 277                         formatted += ", ";
 278                 formatted += i->identifier;
 279                 if(!i->value.empty())
 280                         formatted += format("=%s", i->value);
 281         }
 282         formatted += format(") %s;", layout.interface);
 283 }
 284
 285 void ProgramCompiler::Formatter::visit(StructDeclaration &strct)
 286 {
 287         formatted += format("struct %s\n", strct.name);
 288         strct.members.visit(*this);
 289         formatted += ';';
 290 }
 291
 292 void ProgramCompiler::Formatter::visit(VariableDeclaration &var)
 293 {
 294         if(var.constant)
 295                 formatted += "const ";
 296         if(!var.sampling.empty())
 297                 formatted += format("%s ", var.sampling);
 298         if(!var.interface.empty() && var.interface!=block_interface)
 299                 formatted += format("%s ", var.interface);
 300         formatted += format("%s %s", var.type, var.name);
 301         if(var.array)
 302         {
 303                 formatted += '[';
 304                 if(var.array_size)
 305                         var.array_size->visit(*this);
 306                 formatted += ']';
 307         }
 308         if(var.init_expression)
 309         {
 310                 formatted += " = ";
 311                 var.init_expression->visit(*this);
 312         }
 313         if(!parameter_list)
 314                 formatted += ';';
 315 }
 316
 317 void ProgramCompiler::Formatter::visit(InterfaceBlock &iface)
 318 {
 319         SetForScope<string> set(block_interface, iface.interface);
 320         formatted += format("%s %s\n", iface.interface, iface.name);
 321         iface.members.visit(*this);
 322         formatted += ';';
 323 }
 324
 325 void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 326 {
 327         formatted += format("%s %s(", func.return_type, func.name);
 328         for(vector<NodePtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 329         {
 330                 if(i!=func.parameters.begin())
 331                         formatted += ", ";
 332                 SetFlag set(parameter_list);
 333                 (*i)->visit(*this);
 334         }
 335         formatted += ')';
 336         if(func.definition)
 337         {
 338                 formatted += '\n';
 339                 func.body.visit(*this);
 340         }
 341         else
 342                 formatted += ';';
 343 }
 344
 345 void ProgramCompiler::Formatter::visit(Conditional &cond)
 346 {
 347         if(else_if)
 348         {
 349                 formatted += ' ';
 350                 else_if = false;
 351         }
 352
 353         formatted += "if(";
 354         cond.condition->visit(*this);
 355         formatted += ")\n";
 356
 357         cond.body.visit(*this);
 358         if(!cond.else_body.body.empty())
 359         {
 360                 formatted += format("\n%selse", string(indent*2, ' '));
 361                 SetFlag set(else_if);
 362                 cond.else_body.visit(*this);
 363         }
 364 }
 365
 366 void ProgramCompiler::Formatter::visit(Iteration &iter)
 367 {
 368         formatted += "for(";
 369         iter.init_statement->visit(*this);
 370         formatted += ' ';
 371         iter.condition->visit(*this);
 372         formatted += "; ";
 373         iter.loop_expression->visit(*this);
 374         formatted += ")\n";
 375         iter.body.visit(*this);
 376 }
 377
 378 void ProgramCompiler::Formatter::visit(Return &ret)
 379 {
 380         formatted += "return ";
 381         ret.expression->visit(*this);
 382         formatted += ';';
 383 }
 384
 385
 386 ProgramCompiler::VariableResolver::VariableResolver():
 387         anonymous(false),
 388         record_target(false),
 389         assignment_target(0),
 390         self_referencing(false)
 391 { }
 392
 393 void ProgramCompiler::VariableResolver::apply(Stage &s)
 394 {
 395         SetForScope<Stage *> set(stage, &s);
 396         Stage *builtins = get_builtins(stage->type);
 397         if(builtins)
 398                 blocks.push_back(&builtins->content);
 399         stage->content.visit(*this);
 400         if(builtins)
 401                 blocks.pop_back();
 402 }
 403
 404 void ProgramCompiler::VariableResolver::visit(Block &block)
 405 {
 406         blocks.push_back(&block);
 407         block.variables.clear();
 408         TraversingVisitor::visit(block);
 409         blocks.pop_back();
 410 }
 411
 412 void ProgramCompiler::VariableResolver::visit(VariableReference &var)
 413 {
 414         var.declaration = 0;
 415         type = 0;
 416         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 417         {
 418                 --i;
 419                 map<string, VariableDeclaration *>::iterator j = (*i)->variables.find(var.name);
 420                 if(j!=(*i)->variables.end())
 421                 {
 422                         var.declaration = j->second;
 423                         type = j->second->type_declaration;
 424                         break;
 425                 }
 426         }
 427
 428         if(record_target)
 429         {
 430                 if(assignment_target)
 431                 {
 432                         record_target = false;
 433                         assignment_target = 0;
 434                 }
 435                 else
 436                         assignment_target = var.declaration;
 437         }
 438         else if(var.declaration && var.declaration==assignment_target)
 439                 self_referencing = true;
 440 }
 441
 442 void ProgramCompiler::VariableResolver::visit(MemberAccess &memacc)
 443 {
 444         type = 0;
 445         TraversingVisitor::visit(memacc);
 446         memacc.declaration = 0;
 447         if(type)
 448         {
 449                 map<string, VariableDeclaration *>::iterator i = type->members.variables.find(memacc.member);
 450                 if(i!=type->members.variables.end())
 451                 {
 452                         memacc.declaration = i->second;
 453                         type = i->second->type_declaration;
 454                 }
 455                 else
 456                         type = 0;
 457         }
 458 }
 459
 460 void ProgramCompiler::VariableResolver::visit(BinaryExpression &binary)
 461 {
 462         if(binary.oper=="[")
 463         {
 464                 {
 465                         SetForScope<bool> set(record_target, false);
 466                         binary.right->visit(*this);
 467                 }
 468                 type = 0;
 469                 binary.left->visit(*this);
 470         }
 471         else
 472         {
 473                 TraversingVisitor::visit(binary);
 474                 type = 0;
 475         }
 476 }
 477
 478 void ProgramCompiler::VariableResolver::visit(Assignment &assign)
 479 {
 480         {
 481                 SetFlag set(record_target);
 482                 assignment_target = 0;
 483                 assign.left->visit(*this);
 484         }
 485
 486         self_referencing = false;
 487         assign.right->visit(*this);
 488
 489         assign.self_referencing = (self_referencing || assign.oper!="=");
 490         assign.target_declaration = assignment_target;
 491 }
 492
 493 void ProgramCompiler::VariableResolver::visit(StructDeclaration &strct)
 494 {
 495         TraversingVisitor::visit(strct);
 496         blocks.back()->types[strct.name] = &strct;
 497 }
 498
 499 void ProgramCompiler::VariableResolver::visit(VariableDeclaration &var)
 500 {
 501         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 502         {
 503                 --i;
 504                 map<string, StructDeclaration *>::iterator j = (*i)->types.find(var.type);
 505                 if(j!=(*i)->types.end())
 506                         var.type_declaration = j->second;
 507         }
 508
 509         if(!block_interface.empty() && var.interface.empty())
 510                 var.interface = block_interface;
 511
 512         TraversingVisitor::visit(var);
 513         blocks.back()->variables[var.name] = &var;
 514         if(anonymous && blocks.size()>1)
 515                 blocks[blocks.size()-2]->variables[var.name] = &var;
 516 }
 517
 518 void ProgramCompiler::VariableResolver::visit(InterfaceBlock &iface)
 519 {
 520         SetFlag set(anonymous);
 521         SetForScope<string> set2(block_interface, iface.interface);
 522         TraversingVisitor::visit(iface);
 523 }
 524
 525
 526 ProgramCompiler::InterfaceGenerator::InterfaceGenerator():
 527         scope_level(0),
 528         remove_node(false)
 529 { }
 530
 531 string ProgramCompiler::InterfaceGenerator::get_out_prefix(StageType type)
 532 {
 533         if(type==VERTEX)
 534                 return "_vs_out_";
 535         else if(type==GEOMETRY)
 536                 return "_gs_out_";
 537         else
 538                 return string();
 539 }
 540
 541 void ProgramCompiler::InterfaceGenerator::apply(Stage &s)
 542 {
 543         SetForScope<Stage *> set(stage, &s);
 544         if(stage->previous)
 545                 in_prefix = get_out_prefix(stage->previous->type);
 546         out_prefix = get_out_prefix(stage->type);
 547         stage->content.visit(*this);
 548 }
 549
 550 void ProgramCompiler::InterfaceGenerator::visit(Block &block)
 551 {
 552         SetForScope<unsigned> set(scope_level, scope_level+1);
 553         for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 554         {
 555                 (*i)->visit(*this);
 556
 557                 if(scope_level==1)
 558                 {
 559                         for(map<string, VariableDeclaration *>::iterator j=iface_declarations.begin(); j!=iface_declarations.end(); ++j)
 560                         {
 561                                 list<NodePtr<Node> >::iterator k = block.body.insert(i, j->second);
 562                                 (*k)->visit(*this);
 563                         }
 564                         iface_declarations.clear();
 565                 }
 566
 567                 for(list<Node *>::iterator j=insert_nodes.begin(); j!=insert_nodes.end(); ++j)
 568                         block.body.insert(i, *j);
 569                 insert_nodes.clear();
 570
 571                 if(remove_node)
 572                         block.body.erase(i++);
 573                 else
 574                         ++i;
 575                 remove_node = false;
 576         }
 577 }
 578
 579 string ProgramCompiler::InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
 580 {
 581         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
 582         return prefix+name.substr(offset);
 583 }
 584
 585 bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
 586 {
 587         const map<string, VariableDeclaration *> &stage_vars = (iface=="in" ? stage->in_variables : stage->out_variables);
 588         if(stage_vars.count(name) || iface_declarations.count(name))
 589                 return false;
 590
 591         VariableDeclaration* iface_var = new VariableDeclaration;
 592         iface_var->sampling = var.sampling;
 593         iface_var->interface = iface;
 594         iface_var->type = var.type;
 595         iface_var->type_declaration = var.type_declaration;
 596         iface_var->name = name;
 597         if(stage->type==GEOMETRY)
 598                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
 599         else
 600                 iface_var->array = var.array;
 601         if(iface_var->array)
 602                 iface_var->array_size = var.array_size;
 603         if(iface=="in")
 604                 iface_var->linked_declaration = &var;
 605         iface_declarations[name] = iface_var;
 606
 607         return true;
 608 }
 609
 610 void ProgramCompiler::InterfaceGenerator::insert_assignment(const string &left, ProgramSyntax::Expression *right)
 611 {
 612         Assignment *assign = new Assignment;
 613         VariableReference *ref = new VariableReference;
 614         ref->name = left;
 615         assign->left = ref;
 616         assign->oper = "=";
 617         assign->right = right;
 618
 619         ExpressionStatement *stmt = new ExpressionStatement;
 620         stmt->expression = assign;
 621         insert_nodes.push_back(stmt);
 622 }
 623
 624 void ProgramCompiler::InterfaceGenerator::visit(VariableReference &var)
 625 {
 626         if(var.declaration || !stage->previous)
 627                 return;
 628         if(iface_declarations.count(var.name))
 629                 return;
 630
 631         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 632         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
 633         if(i==prev_out.end())
 634                 i = prev_out.find(in_prefix+var.name);
 635         if(i!=prev_out.end())
 636                 generate_interface(*i->second, "in", var.name);
 637 }
 638
 639 void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &var)
 640 {
 641         if(var.interface=="out")
 642         {
 643                 if(scope_level==1)
 644                         stage->out_variables[var.name] = &var;
 645                 else if(generate_interface(var, "out", change_prefix(var.name, string())))
 646                 {
 647                         remove_node = true;
 648                         if(var.init_expression)
 649                                 insert_assignment(var.name, var.init_expression->clone());
 650                 }
 651         }
 652         else if(var.interface=="in")
 653         {
 654                 stage->in_variables[var.name] = &var;
 655                 if(var.linked_declaration)
 656                         var.linked_declaration->linked_declaration = &var;
 657                 else if(stage->previous)
 658                 {
 659                         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 660                         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
 661                         if(i!=prev_out.end())
 662                         {
 663                                 var.linked_declaration = i->second;
 664                                 i->second->linked_declaration = &var;
 665                         }
 666                 }
 667         }
 668
 669         TraversingVisitor::visit(var);
 670 }
 671
 672 void ProgramCompiler::InterfaceGenerator::visit(Passthrough &pass)
 673 {
 674         vector<VariableDeclaration *> pass_vars;
 675
 676         for(map<string, VariableDeclaration *>::const_iterator i=stage->in_variables.begin(); i!=stage->in_variables.end(); ++i)
 677                 pass_vars.push_back(i->second);
 678         for(map<string, VariableDeclaration *>::const_iterator i=iface_declarations.begin(); i!=iface_declarations.end(); ++i)
 679                 if(i->second->interface=="in")
 680                         pass_vars.push_back(i->second);
 681
 682         if(stage->previous)
 683         {
 684                 const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 685                 for(map<string, VariableDeclaration *>::const_iterator i=prev_out.begin(); i!=prev_out.end(); ++i)
 686                 {
 687                         bool linked = false;
 688                         for(vector<VariableDeclaration *>::const_iterator j=pass_vars.begin(); (!linked && j!=pass_vars.end()); ++j)
 689                                 linked = ((*j)->linked_declaration==i->second);
 690
 691                         if(!linked && generate_interface(*i->second, "in", i->second->name))
 692                                 pass_vars.push_back(i->second);
 693                 }
 694         }
 695
 696         if(stage->type==GEOMETRY)
 697         {
 698                 VariableReference *ref = new VariableReference;
 699                 ref->name = "gl_in";
 700
 701                 BinaryExpression *subscript = new BinaryExpression;
 702                 subscript->left = ref;
 703                 subscript->oper = "[";
 704                 subscript->right = pass.subscript;
 705                 subscript->after = "]";
 706
 707                 MemberAccess *memacc = new MemberAccess;
 708                 memacc->left = subscript;
 709                 memacc->member = "gl_Position";
 710
 711                 insert_assignment("gl_Position", memacc);
 712         }
 713
 714         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
 715         {
 716                 string out_name = change_prefix((*i)->name, out_prefix);
 717                 generate_interface(**i, "out", out_name);
 718
 719                 VariableReference *ref = new VariableReference;
 720                 ref->name = (*i)->name;
 721                 if(pass.subscript)
 722                 {
 723                         BinaryExpression *subscript = new BinaryExpression;
 724                         subscript->left = ref;
 725                         subscript->oper = "[";
 726                         subscript->right = pass.subscript;
 727                         subscript->after = "]";
 728                         insert_assignment(out_name, subscript);
 729                 }
 730                 else
 731                         insert_assignment(out_name, ref);
 732         }
 733
 734         remove_node = true;
 735 }
 736
 737
 738 void ProgramCompiler::VariableRenamer::visit(VariableReference &var)
 739 {
 740         if(var.declaration)
 741                 var.name = var.declaration->name;
 742 }
 743
 744 void ProgramCompiler::VariableRenamer::visit(VariableDeclaration &var)
 745 {
 746         if(var.linked_declaration)
 747                 var.name = var.linked_declaration->name;
 748         TraversingVisitor::visit(var);
 749 }
 750
 751
 752 ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
 753         aggregate(0),
 754         assignment(0),
 755         assignment_target(false)
 756 { }
 757
 758 void ProgramCompiler::UnusedVariableLocator::apply(Stage &s)
 759 {
 760         assignments.push_back(BlockAssignmentMap());
 761         Visitor::apply(s);
 762         assignments.pop_back();
 763 }
 764
 765 void ProgramCompiler::UnusedVariableLocator::visit(VariableReference &var)
 766 {
 767         unused_nodes.erase(var.declaration);
 768
 769         map<VariableDeclaration *, Node *>::iterator i = aggregates.find(var.declaration);
 770         if(i!=aggregates.end())
 771                 unused_nodes.erase(i->second);
 772
 773         if(assignment_target)
 774                 return;
 775
 776         for(vector<BlockAssignmentMap>::iterator j=assignments.end(); j!=assignments.begin(); )
 777         {
 778                 --j;
 779                 BlockAssignmentMap::iterator k = j->find(var.declaration);
 780                 if(k!=j->end())
 781                 {
 782                         for(vector<Node *>::iterator l=k->second.nodes.begin(); l!=k->second.nodes.end(); ++l)
 783                                 unused_nodes.erase(*l);
 784                         j->erase(k);
 785                         break;
 786                 }
 787         }
 788 }
 789
 790 void ProgramCompiler::UnusedVariableLocator::visit(MemberAccess &memacc)
 791 {
 792         TraversingVisitor::visit(memacc);
 793         unused_nodes.erase(memacc.declaration);
 794 }
 795
 796 void ProgramCompiler::UnusedVariableLocator::visit(BinaryExpression &binary)
 797 {
 798         if(binary.oper=="[")
 799         {
 800                 binary.left->visit(*this);
 801                 SetForScope<bool> set(assignment_target, false);
 802                 binary.right->visit(*this);
 803         }
 804         else
 805                 TraversingVisitor::visit(binary);
 806 }
 807
 808 void ProgramCompiler::UnusedVariableLocator::visit(Assignment &assign)
 809 {
 810         {
 811                 SetForScope<bool> set(assignment_target, !assign.self_referencing);
 812                 assign.left->visit(*this);
 813         }
 814         assign.right->visit(*this);
 815         assignment = &assign;
 816 }
 817
 818 void ProgramCompiler::UnusedVariableLocator::record_assignment(VariableDeclaration &var, Node &node, bool self_ref)
 819 {
 820         unused_nodes.insert(&node);
 821         BlockAssignmentMap &block_assignments = assignments.back();
 822         AssignmentList &var_assignments = block_assignments[&var];
 823         if(!self_ref)
 824                 var_assignments.nodes.clear();
 825         var_assignments.nodes.push_back(&node);
 826         var_assignments.conditional = false;
 827         var_assignments.self_referencing = self_ref;
 828 }
 829
 830 void ProgramCompiler::UnusedVariableLocator::visit(ExpressionStatement &expr)
 831 {
 832         assignment = 0;
 833         TraversingVisitor::visit(expr);
 834         if(assignment && assignment->target_declaration)
 835                 record_assignment(*assignment->target_declaration, expr, assignment->self_referencing);
 836 }
 837
 838 void ProgramCompiler::UnusedVariableLocator::visit(StructDeclaration &strct)
 839 {
 840         SetForScope<Node *> set(aggregate, &strct);
 841         unused_nodes.insert(&strct);
 842         TraversingVisitor::visit(strct);
 843 }
 844
 845 void ProgramCompiler::UnusedVariableLocator::visit(VariableDeclaration &var)
 846 {
 847         if(aggregate)
 848                 aggregates[&var] = aggregate;
 849         else
 850         {
 851                 unused_nodes.insert(&var);
 852                 if(var.init_expression)
 853                         record_assignment(var, *var.init_expression, false);
 854         }
 855         unused_nodes.erase(var.type_declaration);
 856         TraversingVisitor::visit(var);
 857 }
 858
 859 void ProgramCompiler::UnusedVariableLocator::visit(InterfaceBlock &iface)
 860 {
 861         SetForScope<Node *> set(aggregate, &iface);
 862         unused_nodes.insert(&iface);
 863         TraversingVisitor::visit(iface);
 864 }
 865
 866 void ProgramCompiler::UnusedVariableLocator::visit(FunctionDeclaration &func)
 867 {
 868         assignments.push_back(BlockAssignmentMap());
 869
 870         for(vector<NodePtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 871                 (*i)->visit(*this);
 872         func.body.visit(*this);
 873
 874         BlockAssignmentMap &block_assignments = assignments.back();
 875         for(map<string, VariableDeclaration *>::iterator i=func.body.variables.begin(); i!=func.body.variables.end(); ++i)
 876                 block_assignments.erase(i->second);
 877         for(BlockAssignmentMap::iterator i=block_assignments.begin(); i!=block_assignments.end(); ++i)
 878         {
 879                 if(i->first->interface=="out" && stage->type!=FRAGMENT && !i->first->linked_declaration)
 880                         continue;
 881
 882                 for(vector<Node *>::iterator j=i->second.nodes.begin(); j!=i->second.nodes.end(); ++j)
 883                         unused_nodes.erase(*j);
 884         }
 885
 886         assignments.pop_back();
 887 }
 888
 889 void ProgramCompiler::UnusedVariableLocator::merge_down_assignments()
 890 {
 891         BlockAssignmentMap &parent_assignments = assignments[assignments.size()-2];
 892         BlockAssignmentMap &block_assignments = assignments.back();
 893         for(BlockAssignmentMap::iterator i=block_assignments.begin(); i!=block_assignments.end(); ++i)
 894         {
 895                 BlockAssignmentMap::iterator j = parent_assignments.find(i->first);
 896                 if(j==parent_assignments.end())
 897                         parent_assignments.insert(*i);
 898                 else if(i->second.self_referencing || i->second.conditional)
 899                 {
 900                         j->second.nodes.insert(j->second.nodes.end(), i->second.nodes.begin(), i->second.nodes.end());
 901                         j->second.conditional |= i->second.conditional;
 902                         j->second.self_referencing |= i->second.self_referencing;
 903                 }
 904                 else
 905                         j->second = i->second;
 906         }
 907         assignments.pop_back();
 908 }
 909
 910 void ProgramCompiler::UnusedVariableLocator::visit(Conditional &cond)
 911 {
 912         cond.condition->visit(*this);
 913         assignments.push_back(BlockAssignmentMap());
 914         cond.body.visit(*this);
 915
 916         BlockAssignmentMap if_assignments;
 917         swap(assignments.back(), if_assignments);
 918         cond.else_body.visit(*this);
 919
 920         BlockAssignmentMap &else_assignments = assignments.back();
 921         for(BlockAssignmentMap::iterator i=else_assignments.begin(); i!=else_assignments.end(); ++i)
 922         {
 923                 BlockAssignmentMap::iterator j = if_assignments.find(i->first);
 924                 if(j!=if_assignments.end())
 925                 {
 926                         i->second.nodes.insert(i->second.nodes.end(), j->second.nodes.begin(), j->second.nodes.end());
 927                         i->second.conditional |= j->second.conditional;
 928                         i->second.self_referencing |= j->second.self_referencing;
 929                         if_assignments.erase(j);
 930                 }
 931                 else
 932                         i->second.conditional = true;
 933         }
 934
 935         for(BlockAssignmentMap::iterator i=if_assignments.begin(); i!=if_assignments.end(); ++i)
 936         {
 937                 i->second.conditional = true;
 938                 else_assignments.insert(*i);
 939         }
 940
 941         merge_down_assignments();
 942 }
 943
 944 void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
 945 {
 946         assignments.push_back(BlockAssignmentMap());
 947         TraversingVisitor::visit(iter);
 948         merge_down_assignments();
 949 }
 950
 951
 952 void ProgramCompiler::NodeRemover::visit(Block &block)
 953 {
 954         for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 955         {
 956                 (*i)->visit(*this);
 957                 if(to_remove.count(&**i))
 958                         block.body.erase(i++);
 959                 else
 960                         ++i;
 961         }
 962 }
 963
 964 void ProgramCompiler::NodeRemover::visit(VariableDeclaration &var)
 965 {
 966         if(to_remove.count(&var))
 967         {
 968                 stage->in_variables.erase(var.name);
 969                 stage->out_variables.erase(var.name);
 970                 if(var.linked_declaration)
 971                         var.linked_declaration->linked_declaration = 0;
 972         }
 973         else if(var.init_expression && to_remove.count(&*var.init_expression))
 974                 var.init_expression = 0;
 975 }
 976
 977 } // namespace GL
 978 } // namespace Msp