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