source/glsl/generate.cpp

   1 #include <msp/core/raii.h>
   2 #include "builtin.h"
   3 #include "generate.h"
   4
   5 using namespace std;
   6
   7 namespace Msp {
   8 namespace GL {
   9 namespace SL {
  10
  11 void DeclarationCombiner::apply(Stage &stage)
  12 {
  13         stage.content.visit(*this);
  14         NodeRemover().apply(stage, nodes_to_remove);
  15 }
  16
  17 void DeclarationCombiner::visit(Block &block)
  18 {
  19         if(current_block)
  20                 return;
  21
  22         TraversingVisitor::visit(block);
  23 }
  24
  25 void DeclarationCombiner::visit(FunctionDeclaration &func)
  26 {
  27         vector<FunctionDeclaration *> &decls = functions[func.name];
  28         if(func.definition)
  29         {
  30                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
  31                 {
  32                         (*i)->definition = func.definition;
  33                         (*i)->body.body.clear();
  34                 }
  35         }
  36         decls.push_back(&func);
  37 }
  38
  39 void DeclarationCombiner::visit(VariableDeclaration &var)
  40 {
  41         VariableDeclaration *&ptr = variables[var.name];
  42         if(ptr)
  43         {
  44                 ptr->type = var.type;
  45                 if(var.init_expression)
  46                         ptr->init_expression = var.init_expression;
  47                 if(var.layout)
  48                 {
  49                         if(ptr->layout)
  50                         {
  51                                 for(vector<Layout::Qualifier>::iterator i=var.layout->qualifiers.begin(); i!=var.layout->qualifiers.end(); ++i)
  52                                 {
  53                                         bool found = false;
  54                                         for(vector<Layout::Qualifier>::iterator j=ptr->layout->qualifiers.begin(); (!found && j!=ptr->layout->qualifiers.end()); ++j)
  55                                                 if(j->name==i->name)
  56                                                 {
  57                                                         j->has_value = i->value;
  58                                                         j->value = i->value;
  59                                                         found = true;
  60                                                 }
  61
  62                                         if(!found)
  63                                                 ptr->layout->qualifiers.push_back(*i);
  64                                 }
  65                         }
  66                         else
  67                                 ptr->layout = var.layout;
  68                 }
  69                 nodes_to_remove.insert(&var);
  70         }
  71         else
  72                 ptr = &var;
  73 }
  74
  75
  76 void BlockResolver::enter(Block &block)
  77 {
  78         block.parent = current_block;
  79 }
  80
  81 void BlockResolver::visit(InterfaceBlock &iface)
  82 {
  83         current_block->interfaces.insert(&iface);
  84         TraversingVisitor::visit(iface);
  85 }
  86
  87
  88 VariableResolver::VariableResolver():
  89         record_target(false),
  90         assignment_target(0),
  91         self_referencing(false)
  92 { }
  93
  94 void VariableResolver::apply(Stage &stage)
  95 {
  96         Stage *builtin_stage = get_builtins(stage.type);
  97         builtins = (builtin_stage ? &builtin_stage->content : 0);
  98         stage.content.visit(*this);
  99 }
 100
 101 Block *VariableResolver::next_block(Block &block)
 102 {
 103         return block.parent ? block.parent : &block!=builtins ? builtins : 0;
 104 }
 105
 106 void VariableResolver::enter(Block &block)
 107 {
 108         block.variables.clear();
 109 }
 110
 111 void VariableResolver::visit(VariableReference &var)
 112 {
 113         var.declaration = 0;
 114         type = 0;
 115         for(Block *block=current_block; block; block=next_block(*block))
 116         {
 117                 map<string, VariableDeclaration *>::iterator i = block->variables.find(var.name);
 118                 if(i!=block->variables.end())
 119                         var.declaration = i->second;
 120                 else
 121                 {
 122                         const set<InterfaceBlock *> &ifaces = block->interfaces;
 123                         for(set<InterfaceBlock *>::const_iterator j=ifaces.begin(); (!var.declaration && j!=ifaces.end()); ++j)
 124                         {
 125                                 i = (*j)->members.variables.find(var.name);
 126                                 if(i!=(*j)->members.variables.end())
 127                                         var.declaration = i->second;
 128                         }
 129                 }
 130
 131                 if(var.declaration)
 132                 {
 133                         type = var.declaration->type_declaration;
 134                         break;
 135                 }
 136         }
 137
 138         if(record_target)
 139         {
 140                 if(assignment_target)
 141                 {
 142                         record_target = false;
 143                         assignment_target = 0;
 144                 }
 145                 else
 146                         assignment_target = var.declaration;
 147         }
 148         else if(var.declaration && var.declaration==assignment_target)
 149                 self_referencing = true;
 150 }
 151
 152 void VariableResolver::visit(MemberAccess &memacc)
 153 {
 154         type = 0;
 155         TraversingVisitor::visit(memacc);
 156         memacc.declaration = 0;
 157         if(type)
 158         {
 159                 map<string, VariableDeclaration *>::iterator i = type->members.variables.find(memacc.member);
 160                 if(i!=type->members.variables.end())
 161                 {
 162                         memacc.declaration = i->second;
 163                         type = i->second->type_declaration;
 164                 }
 165                 else
 166                         type = 0;
 167         }
 168 }
 169
 170 void VariableResolver::visit(BinaryExpression &binary)
 171 {
 172         if(binary.oper=="[")
 173         {
 174                 {
 175                         SetForScope<bool> set(record_target, false);
 176                         binary.right->visit(*this);
 177                 }
 178                 type = 0;
 179                 binary.left->visit(*this);
 180         }
 181         else
 182         {
 183                 TraversingVisitor::visit(binary);
 184                 type = 0;
 185         }
 186 }
 187
 188 void VariableResolver::visit(Assignment &assign)
 189 {
 190         {
 191                 SetFlag set(record_target);
 192                 assignment_target = 0;
 193                 assign.left->visit(*this);
 194         }
 195
 196         self_referencing = false;
 197         assign.right->visit(*this);
 198
 199         assign.self_referencing = (self_referencing || assign.oper!="=");
 200         assign.target_declaration = assignment_target;
 201 }
 202
 203 void VariableResolver::visit(StructDeclaration &strct)
 204 {
 205         TraversingVisitor::visit(strct);
 206         current_block->types[strct.name] = &strct;
 207 }
 208
 209 void VariableResolver::visit(VariableDeclaration &var)
 210 {
 211         for(Block *block=current_block; block; block=next_block(*block))
 212         {
 213                 map<string, StructDeclaration *>::iterator j = block->types.find(var.type);
 214                 if(j!=block->types.end())
 215                         var.type_declaration = j->second;
 216         }
 217
 218         if(!block_interface.empty() && var.interface.empty())
 219                 var.interface = block_interface;
 220
 221         TraversingVisitor::visit(var);
 222         current_block->variables[var.name] = &var;
 223 }
 224
 225 void VariableResolver::visit(InterfaceBlock &iface)
 226 {
 227         SetForScope<string> set_iface(block_interface, iface.interface);
 228         TraversingVisitor::visit(iface);
 229 }
 230
 231
 232 void FunctionResolver::visit(FunctionCall &call)
 233 {
 234         map<string, vector<FunctionDeclaration *> >::iterator i = functions.find(call.name);
 235         if(i!=functions.end())
 236                 call.declaration = i->second.back();
 237
 238         TraversingVisitor::visit(call);
 239 }
 240
 241 void FunctionResolver::visit(FunctionDeclaration &func)
 242 {
 243         vector<FunctionDeclaration *> &decls = functions[func.name];
 244         if(func.definition)
 245         {
 246                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
 247                         (*i)->definition = func.definition;
 248                 decls.clear();
 249                 decls.push_back(&func);
 250         }
 251         else if(!decls.empty() && decls.back()->definition)
 252                 func.definition = decls.back()->definition;
 253         else
 254                 decls.push_back(&func);
 255
 256         TraversingVisitor::visit(func);
 257 }
 258
 259
 260 InterfaceGenerator::InterfaceGenerator():
 261         stage(0),
 262         function_scope(false)
 263 { }
 264
 265 string InterfaceGenerator::get_out_prefix(Stage::Type type)
 266 {
 267         if(type==Stage::VERTEX)
 268                 return "_vs_out_";
 269         else if(type==Stage::GEOMETRY)
 270                 return "_gs_out_";
 271         else
 272                 return string();
 273 }
 274
 275 void InterfaceGenerator::apply(Stage &s)
 276 {
 277         stage = &s;
 278         if(stage->previous)
 279                 in_prefix = get_out_prefix(stage->previous->type);
 280         out_prefix = get_out_prefix(stage->type);
 281         s.content.visit(*this);
 282         NodeRemover().apply(s, nodes_to_remove);
 283 }
 284
 285 void InterfaceGenerator::visit(Block &block)
 286 {
 287         SetForScope<Block *> set_block(current_block, &block);
 288         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
 289         {
 290                 assignment_insert_point = i;
 291                 if(&block==&stage->content)
 292                         iface_insert_point = i;
 293
 294                 (*i)->visit(*this);
 295         }
 296 }
 297
 298 string InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
 299 {
 300         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
 301         return prefix+name.substr(offset);
 302 }
 303
 304 bool InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
 305 {
 306         if(stage->content.variables.count(name))
 307                 return false;
 308
 309         VariableDeclaration* iface_var = new VariableDeclaration;
 310         iface_var->sampling = var.sampling;
 311         iface_var->interface = iface;
 312         iface_var->type = var.type;
 313         iface_var->type_declaration = var.type_declaration;
 314         iface_var->name = name;
 315         if(stage->type==Stage::GEOMETRY)
 316                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
 317         else
 318                 iface_var->array = var.array;
 319         if(iface_var->array)
 320                 iface_var->array_size = var.array_size;
 321         if(iface=="in")
 322         {
 323                 iface_var->linked_declaration = &var;
 324                 var.linked_declaration = iface_var;
 325         }
 326         stage->content.body.insert(iface_insert_point, iface_var);
 327         stage->content.variables[name] = iface_var;
 328
 329         return true;
 330 }
 331
 332 ExpressionStatement &InterfaceGenerator::insert_assignment(const string &left, Expression *right)
 333 {
 334         Assignment *assign = new Assignment;
 335         VariableReference *ref = new VariableReference;
 336         ref->name = left;
 337         assign->left = ref;
 338         assign->oper = "=";
 339         assign->right = right;
 340
 341         ExpressionStatement *stmt = new ExpressionStatement;
 342         stmt->expression = assign;
 343         current_block->body.insert(assignment_insert_point, stmt);
 344         stmt->visit(*this);
 345
 346         return *stmt;
 347 }
 348
 349 void InterfaceGenerator::visit(VariableReference &var)
 350 {
 351         if(var.declaration || !stage->previous)
 352                 return;
 353         /* Don't pull a variable from previous stage if we just generated an out
 354         interface in this stage */
 355         if(stage->content.variables.count(var.name))
 356                 return;
 357
 358         const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
 359         map<string, VariableDeclaration *>::const_iterator i = prev_vars.find(var.name);
 360         if(i==prev_vars.end() || i->second->interface!="out")
 361                 i = prev_vars.find(in_prefix+var.name);
 362         if(i!=prev_vars.end() && i->second->interface=="out")
 363         {
 364                 generate_interface(*i->second, "in", i->second->name);
 365                 var.name = i->second->name;
 366         }
 367 }
 368
 369 void InterfaceGenerator::visit(VariableDeclaration &var)
 370 {
 371         if(var.interface=="out")
 372         {
 373                 /* For out variables in function scope, generate a global interface and
 374                 replace the local declaration with an assignment. */
 375                 if(function_scope && generate_interface(var, "out", var.name))
 376                 {
 377                         nodes_to_remove.insert(&var);
 378                         if(var.init_expression)
 379                         {
 380                                 ExpressionStatement &stmt = insert_assignment(var.name, var.init_expression->clone());
 381                                 stmt.source = var.source;
 382                                 stmt.line = var.line;
 383                                 return;
 384                         }
 385                 }
 386         }
 387         else if(var.interface=="in")
 388         {
 389                 /* Try to link in variables in global scope with out variables from
 390                 previous stage */
 391                 if(current_block==&stage->content && !var.linked_declaration && stage->previous)
 392                 {
 393                         const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
 394                         map<string, VariableDeclaration *>::const_iterator i = prev_vars.find(var.name);
 395                         if(i!=prev_vars.end() && i->second->interface=="out")
 396                         {
 397                                 var.linked_declaration = i->second;
 398                                 i->second->linked_declaration = &var;
 399                         }
 400                 }
 401         }
 402
 403         TraversingVisitor::visit(var);
 404 }
 405
 406 void InterfaceGenerator::visit(FunctionDeclaration &func)
 407 {
 408         SetFlag set_scope(function_scope, true);
 409         // Skip parameters because they're not useful here
 410         func.body.visit(*this);
 411 }
 412
 413 void InterfaceGenerator::visit(Passthrough &pass)
 414 {
 415         vector<VariableDeclaration *> pass_vars;
 416
 417         for(map<string, VariableDeclaration *>::const_iterator i=stage->content.variables.begin(); i!=stage->content.variables.end(); ++i)
 418                 if(i->second->interface=="in")
 419                         pass_vars.push_back(i->second);
 420
 421         if(stage->previous)
 422         {
 423                 const map<string, VariableDeclaration *> &prev_vars = stage->previous->content.variables;
 424                 for(map<string, VariableDeclaration *>::const_iterator i=prev_vars.begin(); i!=prev_vars.end(); ++i)
 425                 {
 426                         bool linked = false;
 427                         for(vector<VariableDeclaration *>::const_iterator j=pass_vars.begin(); (!linked && j!=pass_vars.end()); ++j)
 428                                 linked = ((*j)->linked_declaration==i->second);
 429
 430                         if(!linked && generate_interface(*i->second, "in", i->second->name))
 431                                 pass_vars.push_back(i->second);
 432                 }
 433         }
 434
 435         if(stage->type==Stage::GEOMETRY)
 436         {
 437                 VariableReference *ref = new VariableReference;
 438                 ref->name = "gl_in";
 439
 440                 BinaryExpression *subscript = new BinaryExpression;
 441                 subscript->left = ref;
 442                 subscript->oper = "[";
 443                 subscript->right = pass.subscript;
 444                 subscript->after = "]";
 445
 446                 MemberAccess *memacc = new MemberAccess;
 447                 memacc->left = subscript;
 448                 memacc->member = "gl_Position";
 449
 450                 insert_assignment("gl_Position", memacc);
 451         }
 452
 453         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
 454         {
 455                 string out_name = change_prefix((*i)->name, out_prefix);
 456                 generate_interface(**i, "out", out_name);
 457
 458                 VariableReference *ref = new VariableReference;
 459                 ref->name = (*i)->name;
 460                 if(pass.subscript)
 461                 {
 462                         BinaryExpression *subscript = new BinaryExpression;
 463                         subscript->left = ref;
 464                         subscript->oper = "[";
 465                         subscript->right = pass.subscript;
 466                         subscript->after = "]";
 467                         insert_assignment(out_name, subscript);
 468                 }
 469                 else
 470                         insert_assignment(out_name, ref);
 471         }
 472
 473         nodes_to_remove.insert(&pass);
 474 }
 475
 476
 477 DeclarationReorderer::DeclarationReorderer():
 478         kind(NO_DECLARATION)
 479 { }
 480
 481 void DeclarationReorderer::visit(FunctionCall &call)
 482 {
 483         FunctionDeclaration *def = call.declaration;
 484         if(def)
 485                 def = def->definition;
 486         if(def && !ordered_funcs.count(def))
 487                 needed_funcs.insert(def);
 488 }
 489
 490 void DeclarationReorderer::visit(Block &block)
 491 {
 492         if(block.parent)
 493                 return TraversingVisitor::visit(block);
 494
 495         NodeList<Statement>::iterator struct_insert_point = block.body.end();
 496         NodeList<Statement>::iterator variable_insert_point = block.body.end();
 497         NodeList<Statement>::iterator function_insert_point = block.body.end();
 498         unsigned unordered_func_count = 0;
 499         bool ordered_any_funcs = false;
 500
 501         for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); )
 502         {
 503                 kind = NO_DECLARATION;
 504                 (*i)->visit(*this);
 505
 506                 bool moved = false;
 507                 if(kind==STRUCT && struct_insert_point!=block.body.end())
 508                 {
 509                         block.body.insert(struct_insert_point, *i);
 510                         moved = true;
 511                 }
 512                 else if(kind>STRUCT && struct_insert_point==block.body.end())
 513                         struct_insert_point = i;
 514
 515                 if(kind==VARIABLE && variable_insert_point!=block.body.end())
 516                 {
 517                         block.body.insert(variable_insert_point, *i);
 518                         moved = true;
 519                 }
 520                 else if(kind>VARIABLE && variable_insert_point==block.body.end())
 521                         variable_insert_point = i;
 522
 523                 if(kind==FUNCTION)
 524                 {
 525                         if(function_insert_point==block.body.end())
 526                                 function_insert_point = i;
 527
 528                         if(needed_funcs.empty())
 529                         {
 530                                 ordered_funcs.insert(i->get());
 531                                 if(i!=function_insert_point)
 532                                 {
 533                                         block.body.insert(function_insert_point, *i);
 534                                         moved = true;
 535                                 }
 536                                 else
 537                                         ++function_insert_point;
 538                                 ordered_any_funcs = true;
 539                         }
 540                         else
 541                                 ++unordered_func_count;
 542                 }
 543
 544                 if(moved)
 545                 {
 546                         if(function_insert_point==i)
 547                                 ++function_insert_point;
 548                         block.body.erase(i++);
 549                 }
 550                 else
 551                         ++i;
 552
 553                 if(i==block.body.end() && unordered_func_count)
 554                 {
 555                         if(!ordered_any_funcs)
 556                                 // A subset of the remaining functions forms a recursive loop
 557                                 /* TODO pick a function and move it up, adding any necessary
 558                                 declarations */
 559                                 break;
 560
 561                         i = function_insert_point;
 562                         unordered_func_count = 0;
 563                 }
 564         }
 565 }
 566
 567 void DeclarationReorderer::visit(VariableDeclaration &var)
 568 {
 569         TraversingVisitor::visit(var);
 570         kind = VARIABLE;
 571 }
 572
 573 void DeclarationReorderer::visit(FunctionDeclaration &func)
 574 {
 575         needed_funcs.clear();
 576         func.body.visit(*this);
 577         needed_funcs.erase(&func);
 578         kind = FUNCTION;
 579 }
 580
 581 } // namespace SL
 582 } // namespace GL
 583 } // namespace Msp