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(0)
 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(else_if)
 245                 --else_if;
 246
 247         unsigned brace_indent = indent;
 248         bool use_braces = (block.use_braces || (indent && block.body.size()!=1));
 249         if(use_braces)
 250                 formatted += format("%s{\n", string(brace_indent*2, ' '));
 251
 252         SetForScope<unsigned> set(indent, indent+!formatted.empty());
 253         string spaces(indent*2, ' ');
 254         for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 255         {
 256                 if(i!=block.body.begin())
 257                         formatted += '\n';
 258                 formatted += spaces;
 259                 (*i)->visit(*this);
 260                 else_if = 0;
 261         }
 262
 263         if(use_braces)
 264                 formatted += format("\n%s}", string(brace_indent*2, ' '));
 265 }
 266
 267 void ProgramCompiler::Formatter::visit(Layout &layout)
 268 {
 269         formatted += "layout(";
 270         for(vector<Layout::Qualifier>::const_iterator i=layout.qualifiers.begin(); i!=layout.qualifiers.end(); ++i)
 271         {
 272                 if(i!=layout.qualifiers.begin())
 273                         formatted += ", ";
 274                 formatted += i->identifier;
 275                 if(!i->value.empty())
 276                         formatted += format("=%s", i->value);
 277         }
 278         formatted += format(") %s;", layout.interface);
 279 }
 280
 281 void ProgramCompiler::Formatter::visit(StructDeclaration &strct)
 282 {
 283         formatted += format("struct %s\n", strct.name);
 284         strct.members.visit(*this);
 285         formatted += ';';
 286 }
 287
 288 void ProgramCompiler::Formatter::visit(VariableDeclaration &var)
 289 {
 290         if(var.constant)
 291                 formatted += "const ";
 292         if(!var.sampling.empty())
 293                 formatted += format("%s ", var.sampling);
 294         if(!var.interface.empty() && var.interface!=block_interface)
 295                 formatted += format("%s ", var.interface);
 296         formatted += format("%s %s", var.type, var.name);
 297         if(var.array)
 298         {
 299                 formatted += '[';
 300                 if(var.array_size)
 301                         var.array_size->visit(*this);
 302                 formatted += ']';
 303         }
 304         if(var.init_expression)
 305         {
 306                 formatted += " = ";
 307                 var.init_expression->visit(*this);
 308         }
 309         if(!parameter_list)
 310                 formatted += ';';
 311 }
 312
 313 void ProgramCompiler::Formatter::visit(InterfaceBlock &iface)
 314 {
 315         SetForScope<string> set(block_interface, iface.interface);
 316         formatted += format("%s %s\n", iface.interface, iface.name);
 317         iface.members.visit(*this);
 318         formatted += ';';
 319 }
 320
 321 void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
 322 {
 323         formatted += format("%s %s(", func.return_type, func.name);
 324         for(vector<NodePtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 325         {
 326                 if(i!=func.parameters.begin())
 327                         formatted += ", ";
 328                 SetFlag set(parameter_list);
 329                 (*i)->visit(*this);
 330         }
 331         formatted += ')';
 332         if(func.definition)
 333         {
 334                 formatted += '\n';
 335                 func.body.visit(*this);
 336         }
 337         else
 338                 formatted += ';';
 339 }
 340
 341 void ProgramCompiler::Formatter::visit(Conditional &cond)
 342 {
 343         if(else_if)
 344                 formatted.replace(formatted.rfind('\n'), string::npos, 1, ' ');
 345
 346         indent -= else_if;
 347
 348         formatted += "if(";
 349         cond.condition->visit(*this);
 350         formatted += ")\n";
 351
 352         cond.body.visit(*this);
 353         if(!cond.else_body.body.empty())
 354         {
 355                 formatted += format("\n%selse\n", string(indent*2, ' '));
 356                 SetForScope<unsigned> set(else_if, 2);
 357                 cond.else_body.visit(*this);
 358         }
 359 }
 360
 361 void ProgramCompiler::Formatter::visit(Iteration &iter)
 362 {
 363         formatted += "for(";
 364         iter.init_statement->visit(*this);
 365         formatted += ' ';
 366         iter.condition->visit(*this);
 367         formatted += "; ";
 368         iter.loop_expression->visit(*this);
 369         formatted += ")\n";
 370         iter.body.visit(*this);
 371 }
 372
 373 void ProgramCompiler::Formatter::visit(Return &ret)
 374 {
 375         formatted += "return ";
 376         ret.expression->visit(*this);
 377         formatted += ';';
 378 }
 379
 380
 381 ProgramCompiler::VariableResolver::VariableResolver():
 382         anonymous(false),
 383         record_target(false),
 384         assignment_target(0),
 385         self_referencing(false)
 386 { }
 387
 388 void ProgramCompiler::VariableResolver::apply(Stage &s)
 389 {
 390         SetForScope<Stage *> set(stage, &s);
 391         Stage *builtins = get_builtins(stage->type);
 392         if(builtins)
 393                 blocks.push_back(&builtins->content);
 394         stage->content.visit(*this);
 395         if(builtins)
 396                 blocks.pop_back();
 397 }
 398
 399 void ProgramCompiler::VariableResolver::visit(Block &block)
 400 {
 401         blocks.push_back(&block);
 402         block.variables.clear();
 403         TraversingVisitor::visit(block);
 404         blocks.pop_back();
 405 }
 406
 407 void ProgramCompiler::VariableResolver::visit(VariableReference &var)
 408 {
 409         var.declaration = 0;
 410         type = 0;
 411         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 412         {
 413                 --i;
 414                 map<string, VariableDeclaration *>::iterator j = (*i)->variables.find(var.name);
 415                 if(j!=(*i)->variables.end())
 416                 {
 417                         var.declaration = j->second;
 418                         type = j->second->type_declaration;
 419                         break;
 420                 }
 421         }
 422
 423         if(record_target)
 424         {
 425                 if(assignment_target)
 426                 {
 427                         record_target = false;
 428                         assignment_target = 0;
 429                 }
 430                 else
 431                         assignment_target = var.declaration;
 432         }
 433         else if(var.declaration && var.declaration==assignment_target)
 434                 self_referencing = true;
 435 }
 436
 437 void ProgramCompiler::VariableResolver::visit(MemberAccess &memacc)
 438 {
 439         type = 0;
 440         TraversingVisitor::visit(memacc);
 441         memacc.declaration = 0;
 442         if(type)
 443         {
 444                 map<string, VariableDeclaration *>::iterator i = type->members.variables.find(memacc.member);
 445                 if(i!=type->members.variables.end())
 446                 {
 447                         memacc.declaration = i->second;
 448                         type = i->second->type_declaration;
 449                 }
 450                 else
 451                         type = 0;
 452         }
 453 }
 454
 455 void ProgramCompiler::VariableResolver::visit(BinaryExpression &binary)
 456 {
 457         if(binary.oper=="[")
 458         {
 459                 {
 460                         SetForScope<bool> set(record_target, false);
 461                         binary.right->visit(*this);
 462                 }
 463                 type = 0;
 464                 binary.left->visit(*this);
 465         }
 466         else
 467         {
 468                 TraversingVisitor::visit(binary);
 469                 type = 0;
 470         }
 471 }
 472
 473 void ProgramCompiler::VariableResolver::visit(Assignment &assign)
 474 {
 475         {
 476                 SetFlag set(record_target);
 477                 assignment_target = 0;
 478                 assign.left->visit(*this);
 479         }
 480
 481         self_referencing = false;
 482         assign.right->visit(*this);
 483
 484         assign.self_referencing = (self_referencing || assign.oper!="=");
 485         assign.target_declaration = assignment_target;
 486 }
 487
 488 void ProgramCompiler::VariableResolver::visit(StructDeclaration &strct)
 489 {
 490         TraversingVisitor::visit(strct);
 491         blocks.back()->types[strct.name] = &strct;
 492 }
 493
 494 void ProgramCompiler::VariableResolver::visit(VariableDeclaration &var)
 495 {
 496         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
 497         {
 498                 --i;
 499                 map<string, StructDeclaration *>::iterator j = (*i)->types.find(var.type);
 500                 if(j!=(*i)->types.end())
 501                         var.type_declaration = j->second;
 502         }
 503
 504         if(!block_interface.empty() && var.interface.empty())
 505                 var.interface = block_interface;
 506
 507         TraversingVisitor::visit(var);
 508         blocks.back()->variables[var.name] = &var;
 509         if(anonymous && blocks.size()>1)
 510                 blocks[blocks.size()-2]->variables[var.name] = &var;
 511 }
 512
 513 void ProgramCompiler::VariableResolver::visit(InterfaceBlock &iface)
 514 {
 515         SetFlag set(anonymous);
 516         SetForScope<string> set2(block_interface, iface.interface);
 517         TraversingVisitor::visit(iface);
 518 }
 519
 520
 521 ProgramCompiler::InterfaceGenerator::InterfaceGenerator():
 522         scope_level(0),
 523         remove_node(false)
 524 { }
 525
 526 string ProgramCompiler::InterfaceGenerator::get_out_prefix(StageType type)
 527 {
 528         if(type==VERTEX)
 529                 return "_vs_out_";
 530         else if(type==GEOMETRY)
 531                 return "_gs_out_";
 532         else
 533                 return string();
 534 }
 535
 536 void ProgramCompiler::InterfaceGenerator::apply(Stage &s)
 537 {
 538         SetForScope<Stage *> set(stage, &s);
 539         if(stage->previous)
 540                 in_prefix = get_out_prefix(stage->previous->type);
 541         out_prefix = get_out_prefix(stage->type);
 542         stage->content.visit(*this);
 543 }
 544
 545 void ProgramCompiler::InterfaceGenerator::visit(Block &block)
 546 {
 547         SetForScope<unsigned> set(scope_level, scope_level+1);
 548         for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 549         {
 550                 (*i)->visit(*this);
 551
 552                 if(scope_level==1)
 553                 {
 554                         for(map<string, VariableDeclaration *>::iterator j=iface_declarations.begin(); j!=iface_declarations.end(); ++j)
 555                         {
 556                                 list<NodePtr<Node> >::iterator k = block.body.insert(i, j->second);
 557                                 (*k)->visit(*this);
 558                         }
 559                         iface_declarations.clear();
 560                 }
 561
 562                 for(list<Node *>::iterator j=insert_nodes.begin(); j!=insert_nodes.end(); ++j)
 563                         block.body.insert(i, *j);
 564                 insert_nodes.clear();
 565
 566                 if(remove_node)
 567                         block.body.erase(i++);
 568                 else
 569                         ++i;
 570                 remove_node = false;
 571         }
 572 }
 573
 574 string ProgramCompiler::InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
 575 {
 576         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
 577         return prefix+name.substr(offset);
 578 }
 579
 580 bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
 581 {
 582         const map<string, VariableDeclaration *> &stage_vars = (iface=="in" ? stage->in_variables : stage->out_variables);
 583         if(stage_vars.count(name) || iface_declarations.count(name))
 584                 return false;
 585
 586         VariableDeclaration* iface_var = new VariableDeclaration;
 587         iface_var->sampling = var.sampling;
 588         iface_var->interface = iface;
 589         iface_var->type = var.type;
 590         iface_var->type_declaration = var.type_declaration;
 591         iface_var->name = name;
 592         if(stage->type==GEOMETRY)
 593                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
 594         else
 595                 iface_var->array = var.array;
 596         if(iface_var->array)
 597                 iface_var->array_size = var.array_size;
 598         if(iface=="in")
 599                 iface_var->linked_declaration = &var;
 600         iface_declarations[name] = iface_var;
 601
 602         return true;
 603 }
 604
 605 void ProgramCompiler::InterfaceGenerator::insert_assignment(const string &left, ProgramSyntax::Expression *right)
 606 {
 607         Assignment *assign = new Assignment;
 608         VariableReference *ref = new VariableReference;
 609         ref->name = left;
 610         assign->left = ref;
 611         assign->oper = "=";
 612         assign->right = right;
 613
 614         ExpressionStatement *stmt = new ExpressionStatement;
 615         stmt->expression = assign;
 616         insert_nodes.push_back(stmt);
 617 }
 618
 619 void ProgramCompiler::InterfaceGenerator::visit(VariableReference &var)
 620 {
 621         if(var.declaration || !stage->previous)
 622                 return;
 623         if(iface_declarations.count(var.name))
 624                 return;
 625
 626         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 627         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
 628         if(i==prev_out.end())
 629                 i = prev_out.find(in_prefix+var.name);
 630         if(i!=prev_out.end())
 631                 generate_interface(*i->second, "in", var.name);
 632 }
 633
 634 void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &var)
 635 {
 636         if(var.interface=="out")
 637         {
 638                 if(scope_level==1)
 639                         stage->out_variables[var.name] = &var;
 640                 else if(generate_interface(var, "out", change_prefix(var.name, string())))
 641                 {
 642                         remove_node = true;
 643                         if(var.init_expression)
 644                                 insert_assignment(var.name, var.init_expression->clone());
 645                 }
 646         }
 647         else if(var.interface=="in")
 648         {
 649                 stage->in_variables[var.name] = &var;
 650                 if(var.linked_declaration)
 651                         var.linked_declaration->linked_declaration = &var;
 652                 else if(stage->previous)
 653                 {
 654                         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 655                         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
 656                         if(i!=prev_out.end())
 657                         {
 658                                 var.linked_declaration = i->second;
 659                                 i->second->linked_declaration = &var;
 660                         }
 661                 }
 662         }
 663
 664         TraversingVisitor::visit(var);
 665 }
 666
 667 void ProgramCompiler::InterfaceGenerator::visit(Passthrough &pass)
 668 {
 669         vector<VariableDeclaration *> pass_vars;
 670
 671         for(map<string, VariableDeclaration *>::const_iterator i=stage->in_variables.begin(); i!=stage->in_variables.end(); ++i)
 672                 pass_vars.push_back(i->second);
 673         for(map<string, VariableDeclaration *>::const_iterator i=iface_declarations.begin(); i!=iface_declarations.end(); ++i)
 674                 if(i->second->interface=="in")
 675                         pass_vars.push_back(i->second);
 676
 677         if(stage->previous)
 678         {
 679                 const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
 680                 for(map<string, VariableDeclaration *>::const_iterator i=prev_out.begin(); i!=prev_out.end(); ++i)
 681                 {
 682                         bool linked = false;
 683                         for(vector<VariableDeclaration *>::const_iterator j=pass_vars.begin(); (!linked && j!=pass_vars.end()); ++j)
 684                                 linked = ((*j)->linked_declaration==i->second);
 685
 686                         if(!linked && generate_interface(*i->second, "in", i->second->name))
 687                                 pass_vars.push_back(i->second);
 688                 }
 689         }
 690
 691         if(stage->type==GEOMETRY)
 692         {
 693                 VariableReference *ref = new VariableReference;
 694                 ref->name = "gl_in";
 695
 696                 BinaryExpression *subscript = new BinaryExpression;
 697                 subscript->left = ref;
 698                 subscript->oper = "[";
 699                 subscript->right = pass.subscript;
 700                 subscript->after = "]";
 701
 702                 MemberAccess *memacc = new MemberAccess;
 703                 memacc->left = subscript;
 704                 memacc->member = "gl_Position";
 705
 706                 insert_assignment("gl_Position", memacc);
 707         }
 708
 709         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
 710         {
 711                 string out_name = change_prefix((*i)->name, out_prefix);
 712                 generate_interface(**i, "out", out_name);
 713
 714                 VariableReference *ref = new VariableReference;
 715                 ref->name = (*i)->name;
 716                 if(pass.subscript)
 717                 {
 718                         BinaryExpression *subscript = new BinaryExpression;
 719                         subscript->left = ref;
 720                         subscript->oper = "[";
 721                         subscript->right = pass.subscript;
 722                         subscript->after = "]";
 723                         insert_assignment(out_name, subscript);
 724                 }
 725                 else
 726                         insert_assignment(out_name, ref);
 727         }
 728
 729         remove_node = true;
 730 }
 731
 732
 733 void ProgramCompiler::VariableRenamer::visit(VariableReference &var)
 734 {
 735         if(var.declaration)
 736                 var.name = var.declaration->name;
 737 }
 738
 739 void ProgramCompiler::VariableRenamer::visit(VariableDeclaration &var)
 740 {
 741         if(var.linked_declaration)
 742                 var.name = var.linked_declaration->name;
 743         TraversingVisitor::visit(var);
 744 }
 745
 746
 747 ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
 748         aggregate(0),
 749         assignment(0),
 750         assignment_target(false)
 751 { }
 752
 753 void ProgramCompiler::UnusedVariableLocator::apply(Stage &s)
 754 {
 755         assignments.push_back(BlockAssignmentMap());
 756         Visitor::apply(s);
 757         assignments.pop_back();
 758 }
 759
 760 void ProgramCompiler::UnusedVariableLocator::visit(VariableReference &var)
 761 {
 762         unused_nodes.erase(var.declaration);
 763
 764         map<VariableDeclaration *, Node *>::iterator i = aggregates.find(var.declaration);
 765         if(i!=aggregates.end())
 766                 unused_nodes.erase(i->second);
 767
 768         if(assignment_target)
 769                 return;
 770
 771         for(vector<BlockAssignmentMap>::iterator j=assignments.end(); j!=assignments.begin(); )
 772         {
 773                 --j;
 774                 BlockAssignmentMap::iterator k = j->find(var.declaration);
 775                 if(k!=j->end())
 776                 {
 777                         for(vector<Node *>::iterator l=k->second.nodes.begin(); l!=k->second.nodes.end(); ++l)
 778                                 unused_nodes.erase(*l);
 779                         j->erase(k);
 780                         break;
 781                 }
 782         }
 783 }
 784
 785 void ProgramCompiler::UnusedVariableLocator::visit(MemberAccess &memacc)
 786 {
 787         TraversingVisitor::visit(memacc);
 788         unused_nodes.erase(memacc.declaration);
 789 }
 790
 791 void ProgramCompiler::UnusedVariableLocator::visit(BinaryExpression &binary)
 792 {
 793         if(binary.oper=="[")
 794         {
 795                 binary.left->visit(*this);
 796                 SetForScope<bool> set(assignment_target, false);
 797                 binary.right->visit(*this);
 798         }
 799         else
 800                 TraversingVisitor::visit(binary);
 801 }
 802
 803 void ProgramCompiler::UnusedVariableLocator::visit(Assignment &assign)
 804 {
 805         {
 806                 SetForScope<bool> set(assignment_target, !assign.self_referencing);
 807                 assign.left->visit(*this);
 808         }
 809         assign.right->visit(*this);
 810         assignment = &assign;
 811 }
 812
 813 void ProgramCompiler::UnusedVariableLocator::record_assignment(VariableDeclaration &var, Node &node, bool self_ref)
 814 {
 815         unused_nodes.insert(&node);
 816         BlockAssignmentMap &block_assignments = assignments.back();
 817         AssignmentList &var_assignments = block_assignments[&var];
 818         if(!self_ref)
 819                 var_assignments.nodes.clear();
 820         var_assignments.nodes.push_back(&node);
 821         var_assignments.conditional = false;
 822         var_assignments.self_referencing = self_ref;
 823 }
 824
 825 void ProgramCompiler::UnusedVariableLocator::visit(ExpressionStatement &expr)
 826 {
 827         assignment = 0;
 828         TraversingVisitor::visit(expr);
 829         if(assignment && assignment->target_declaration)
 830                 record_assignment(*assignment->target_declaration, expr, assignment->self_referencing);
 831 }
 832
 833 void ProgramCompiler::UnusedVariableLocator::visit(StructDeclaration &strct)
 834 {
 835         SetForScope<Node *> set(aggregate, &strct);
 836         unused_nodes.insert(&strct);
 837         TraversingVisitor::visit(strct);
 838 }
 839
 840 void ProgramCompiler::UnusedVariableLocator::visit(VariableDeclaration &var)
 841 {
 842         if(aggregate)
 843                 aggregates[&var] = aggregate;
 844         else
 845         {
 846                 unused_nodes.insert(&var);
 847                 if(var.init_expression)
 848                         record_assignment(var, *var.init_expression, false);
 849         }
 850         unused_nodes.erase(var.type_declaration);
 851         TraversingVisitor::visit(var);
 852 }
 853
 854 void ProgramCompiler::UnusedVariableLocator::visit(InterfaceBlock &iface)
 855 {
 856         SetForScope<Node *> set(aggregate, &iface);
 857         unused_nodes.insert(&iface);
 858         TraversingVisitor::visit(iface);
 859 }
 860
 861 void ProgramCompiler::UnusedVariableLocator::visit(FunctionDeclaration &func)
 862 {
 863         assignments.push_back(BlockAssignmentMap());
 864
 865         for(vector<NodePtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
 866                 (*i)->visit(*this);
 867         func.body.visit(*this);
 868
 869         BlockAssignmentMap &block_assignments = assignments.back();
 870         for(map<string, VariableDeclaration *>::iterator i=func.body.variables.begin(); i!=func.body.variables.end(); ++i)
 871                 block_assignments.erase(i->second);
 872         for(BlockAssignmentMap::iterator i=block_assignments.begin(); i!=block_assignments.end(); ++i)
 873         {
 874                 if(i->first->interface=="out" && stage->type!=FRAGMENT && !i->first->linked_declaration)
 875                         continue;
 876
 877                 for(vector<Node *>::iterator j=i->second.nodes.begin(); j!=i->second.nodes.end(); ++j)
 878                         unused_nodes.erase(*j);
 879         }
 880
 881         assignments.pop_back();
 882 }
 883
 884 void ProgramCompiler::UnusedVariableLocator::merge_down_assignments()
 885 {
 886         BlockAssignmentMap &parent_assignments = assignments[assignments.size()-2];
 887         BlockAssignmentMap &block_assignments = assignments.back();
 888         for(BlockAssignmentMap::iterator i=block_assignments.begin(); i!=block_assignments.end(); ++i)
 889         {
 890                 BlockAssignmentMap::iterator j = parent_assignments.find(i->first);
 891                 if(j==parent_assignments.end())
 892                         parent_assignments.insert(*i);
 893                 else if(i->second.self_referencing || i->second.conditional)
 894                 {
 895                         j->second.nodes.insert(j->second.nodes.end(), i->second.nodes.begin(), i->second.nodes.end());
 896                         j->second.conditional |= i->second.conditional;
 897                         j->second.self_referencing |= i->second.self_referencing;
 898                 }
 899                 else
 900                         j->second = i->second;
 901         }
 902         assignments.pop_back();
 903 }
 904
 905 void ProgramCompiler::UnusedVariableLocator::visit(Conditional &cond)
 906 {
 907         cond.condition->visit(*this);
 908         assignments.push_back(BlockAssignmentMap());
 909         cond.body.visit(*this);
 910
 911         BlockAssignmentMap if_assignments;
 912         swap(assignments.back(), if_assignments);
 913         cond.else_body.visit(*this);
 914
 915         BlockAssignmentMap &else_assignments = assignments.back();
 916         for(BlockAssignmentMap::iterator i=else_assignments.begin(); i!=else_assignments.end(); ++i)
 917         {
 918                 BlockAssignmentMap::iterator j = if_assignments.find(i->first);
 919                 if(j!=if_assignments.end())
 920                 {
 921                         i->second.nodes.insert(i->second.nodes.end(), j->second.nodes.begin(), j->second.nodes.end());
 922                         i->second.conditional |= j->second.conditional;
 923                         i->second.self_referencing |= j->second.self_referencing;
 924                         if_assignments.erase(j);
 925                 }
 926                 else
 927                         i->second.conditional = true;
 928         }
 929
 930         for(BlockAssignmentMap::iterator i=if_assignments.begin(); i!=if_assignments.end(); ++i)
 931         {
 932                 i->second.conditional = true;
 933                 else_assignments.insert(*i);
 934         }
 935
 936         merge_down_assignments();
 937 }
 938
 939 void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
 940 {
 941         assignments.push_back(BlockAssignmentMap());
 942         TraversingVisitor::visit(iter);
 943         merge_down_assignments();
 944 }
 945
 946
 947 void ProgramCompiler::NodeRemover::visit(Block &block)
 948 {
 949         for(list<NodePtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
 950         {
 951                 (*i)->visit(*this);
 952                 if(to_remove.count(&**i))
 953                         block.body.erase(i++);
 954                 else
 955                         ++i;
 956         }
 957 }
 958
 959 void ProgramCompiler::NodeRemover::visit(VariableDeclaration &var)
 960 {
 961         if(to_remove.count(&var))
 962         {
 963                 stage->in_variables.erase(var.name);
 964                 stage->out_variables.erase(var.name);
 965                 if(var.linked_declaration)
 966                         var.linked_declaration->linked_declaration = 0;
 967         }
 968         else if(var.init_expression && to_remove.count(&*var.init_expression))
 969                 var.init_expression = 0;
 970 }
 971
 972 } // namespace GL
 973 } // namespace Msp