source/glsl/validate.cpp

   1 #include <algorithm>
   2 #include <cstring>
   3 #include <msp/core/raii.h>
   4 #include <msp/strings/format.h>
   5 #include <msp/strings/utils.h>
   6 #include "reflect.h"
   7 #include "validate.h"
   8
   9 using namespace std;
  10
  11 namespace Msp {
  12 namespace GL {
  13 namespace SL {
  14
  15 void Validator::diagnose(Node &node, Node &provoking_node, Diagnostic::Severity severity, const string &message)
  16 {
  17         Diagnostic diag;
  18         diag.severity = severity;
  19         diag.source = node.source;
  20         diag.line = node.line;
  21         diag.provoking_source = provoking_node.source;
  22         diag.provoking_line = provoking_node.line;
  23         diag.message = message;
  24         stage->diagnostics.push_back(diag);
  25
  26         last_provoker = &provoking_node;
  27 }
  28
  29 void Validator::add_info(Node &node, const string &message)
  30 {
  31         if(!last_provoker)
  32                 throw logic_error("Tried to add info without a previous provoker");
  33         diagnose(node, *last_provoker, Diagnostic::INFO, message);
  34 }
  35
  36
  37 const char *DeclarationValidator::describe_variable(ScopeType scope)
  38 {
  39         switch(scope)
  40         {
  41         case GLOBAL: return "global variable";
  42         case STRUCT: return "struct member";
  43         case INTERFACE_BLOCK: return "interface block member";
  44         case FUNCTION_PARAM: return "function parameter";
  45         case FUNCTION: return "local variable";
  46         default: return "variable";
  47         }
  48 }
  49
  50 void DeclarationValidator::visit(Layout &layout)
  51 {
  52         for(const Layout::Qualifier &q: layout.qualifiers)
  53         {
  54                 bool allowed = false;
  55                 string err_descr;
  56                 bool value = true;
  57                 if(q.name=="location")
  58                         allowed = (variable && scope==GLOBAL);
  59                 else if(q.name=="binding" || q.name=="set")
  60                 {
  61                         if(q.name=="set")
  62                         {
  63                                 error(layout, "Layout qualifier 'set' not allowed when targeting OpenGL");
  64                                 continue;
  65                         }
  66
  67                         if(variable)
  68                         {
  69                                 TypeDeclaration *type = variable->type_declaration;
  70                                 while(BasicTypeDeclaration *basic = dynamic_cast<BasicTypeDeclaration *>(type))
  71                                         type = basic->base_type;
  72                                 bool uniform = (variable->interface=="uniform");
  73                                 allowed = (scope==GLOBAL && uniform && dynamic_cast<ImageTypeDeclaration *>(type));
  74                                 err_descr = (uniform ? "variable of non-opaque type" : "non-uniform variable");
  75                         }
  76                         else if(iface_block)
  77                         {
  78                                 allowed = (iface_block->interface=="uniform");
  79                                 err_descr = "non-uniform interface block";
  80                         }
  81                 }
  82                 else if(q.name=="constant_id")
  83                 {
  84                         allowed = (variable && scope==GLOBAL);
  85                         if(allowed)
  86                         {
  87                                 if(!variable->constant)
  88                                 {
  89                                         allowed = false;
  90                                         err_descr = "non-constant variable";
  91                                 }
  92                                 else
  93                                 {
  94                                         BasicTypeDeclaration *basic = dynamic_cast<BasicTypeDeclaration *>(variable->type_declaration);
  95                                         if(!basic || basic->kind<BasicTypeDeclaration::BOOL || basic->kind>BasicTypeDeclaration::INT)
  96                                         {
  97                                                 allowed = false;
  98                                                 err_descr = format("variable of type '%s'",
  99                                                         (variable->type_declaration ? variable->type_declaration->name : variable->type));
 100                                         }
 101                                 }
 102                         }
 103                 }
 104                 else if(q.name=="offset")
 105                         allowed = (variable && scope==INTERFACE_BLOCK && iface_block->interface=="uniform");
 106                 else if(q.name=="align")
 107                         allowed = (scope==INTERFACE_BLOCK && iface_block->interface=="uniform");
 108                 else if(q.name=="points")
 109                 {
 110                         allowed = (stage->type==Stage::GEOMETRY && iface_layout && (iface_layout->interface=="in" || iface_layout->interface=="out"));
 111                         value = false;
 112                 }
 113                 else if(q.name=="lines" || q.name=="lines_adjacency" || q.name=="triangles" || q.name=="triangles_adjacency")
 114                 {
 115                         allowed = (stage->type==Stage::GEOMETRY && iface_layout && iface_layout->interface=="in");
 116                         value = false;
 117                 }
 118                 else if(q.name=="line_strip" || q.name=="triangle_strip")
 119                 {
 120                         allowed = (stage->type==Stage::GEOMETRY && iface_layout && iface_layout->interface=="out");
 121                         value = false;
 122                 }
 123                 else if(q.name=="invocations")
 124                         allowed = (stage->type==Stage::GEOMETRY && iface_layout && iface_layout->interface=="in");
 125                 else if(q.name=="max_vertices")
 126                         allowed = (stage->type==Stage::GEOMETRY && iface_layout && iface_layout->interface=="out");
 127                 else if(q.name=="std140" || q.name=="std430")
 128                 {
 129                         allowed = (iface_block && !variable && iface_block->interface=="uniform");
 130                         value = false;
 131                 }
 132                 else if(q.name=="column_major" || q.name=="row_major")
 133                 {
 134                         allowed = (variable && scope==INTERFACE_BLOCK);
 135                         if(allowed)
 136                         {
 137                                 BasicTypeDeclaration *basic = dynamic_cast<BasicTypeDeclaration *>(variable->type_declaration);
 138                                 while(basic && basic->kind==BasicTypeDeclaration::ARRAY)
 139                                         basic = dynamic_cast<BasicTypeDeclaration *>(basic->base_type);
 140                                 allowed = (basic && basic->kind==BasicTypeDeclaration::MATRIX);
 141                                 err_descr = "non-matrix variable";
 142                         }
 143                 }
 144
 145                 if(!allowed)
 146                 {
 147                         if(err_descr.empty())
 148                         {
 149                                 if(variable)
 150                                         err_descr = describe_variable(scope);
 151                                 else if(iface_block)
 152                                         err_descr = "interface block";
 153                                 else if(iface_layout)
 154                                         err_descr = format("interface '%s'", iface_layout->interface);
 155                                 else
 156                                         err_descr = "unknown declaration";
 157                         }
 158                         error(layout, format("Layout qualifier '%s' not allowed on %s", q.name, err_descr));
 159                 }
 160                 else if(value && !q.has_value)
 161                         error(layout, format("Layout qualifier '%s' requires a value", q.name));
 162                 else if(!value && q.has_value)
 163                         error(layout, format("Layout qualifier '%s' does not allow a value", q.name));
 164         }
 165 }
 166
 167 void DeclarationValidator::visit(InterfaceLayout &layout)
 168 {
 169         SetForScope<InterfaceLayout *> set_layout(iface_layout, &layout);
 170         TraversingVisitor::visit(layout);
 171 }
 172
 173 void DeclarationValidator::visit(BasicTypeDeclaration &type)
 174 {
 175         BasicTypeDeclaration *basic_base = dynamic_cast<BasicTypeDeclaration *>(type.base_type);
 176         BasicTypeDeclaration::Kind base_kind = (basic_base ? basic_base->kind : BasicTypeDeclaration::VOID);
 177
 178         if(type.kind==BasicTypeDeclaration::VECTOR && (base_kind<BasicTypeDeclaration::BOOL || base_kind>BasicTypeDeclaration::FLOAT))
 179                 error(type, format("Invalid base type '%s' for vector type '%s'", type.base, type.name));
 180         else if(type.kind==BasicTypeDeclaration::MATRIX && base_kind!=BasicTypeDeclaration::VECTOR)
 181                 error(type, format("Invalid base type '%s' for matrix type '%s'", type.base, type.name));
 182         else if(type.kind==BasicTypeDeclaration::ARRAY && basic_base && base_kind==BasicTypeDeclaration::VOID)
 183                 error(type, format("Invalid base type '%s' for array type '%s'", type.base, type.name));
 184 }
 185
 186 void DeclarationValidator::visit(ImageTypeDeclaration &type)
 187 {
 188         BasicTypeDeclaration::Kind base_kind = BasicTypeDeclaration::VOID;
 189         if(BasicTypeDeclaration *basic_base = dynamic_cast<BasicTypeDeclaration *>(type.base_type))
 190                 base_kind = basic_base->kind;
 191         if(base_kind!=BasicTypeDeclaration::INT && base_kind!=BasicTypeDeclaration::FLOAT)
 192                 error(type, format("Invalid base type '%s' for image type '%s'", type.base, type.name));
 193 }
 194
 195 void DeclarationValidator::visit(StructDeclaration &strct)
 196 {
 197         SetForScope<ScopeType> set_scope(scope, (scope!=INTERFACE_BLOCK ? STRUCT : scope));
 198         TraversingVisitor::visit(strct);
 199 }
 200
 201 void DeclarationValidator::visit(VariableDeclaration &var)
 202 {
 203         SetForScope<VariableDeclaration *> set_var(variable, &var);
 204
 205         const char *descr = describe_variable(scope);
 206
 207         if(var.layout)
 208         {
 209                 if(scope!=GLOBAL && scope!=INTERFACE_BLOCK)
 210                         error(var, format("Layout qualifier not allowed on %s", descr));
 211                 else
 212                         var.layout->visit(*this);
 213         }
 214
 215         if(var.constant)
 216         {
 217                 if(scope==STRUCT || scope==INTERFACE_BLOCK)
 218                         error(var, format("Constant qualifier not allowed on %s", descr));
 219                 if(!var.init_expression)
 220                         error(var, "Constant variable must have an initializer");
 221         }
 222
 223         if(!var.interpolation.empty() || !var.sampling.empty())
 224         {
 225                 if(var.interface!="in" && stage->type==Stage::VERTEX)
 226                         error(var, "Interpolation qualifier not allowed on vertex input");
 227                 else if(var.interface!="out" && stage->type==Stage::FRAGMENT)
 228                         error(var, "Interpolation qualifier not allowed on fragment output");
 229                 else if((var.interface!="in" && var.interface!="out") || (scope==FUNCTION_PARAM || scope==FUNCTION))
 230                         error(var, "Interpolation qualifier not allowed on non-interpolated variable");
 231         }
 232
 233         if(!var.interface.empty())
 234         {
 235                 if(iface_block && var.interface!=iface_block->interface)
 236                         error(var, format("Mismatched interface qualifier '%s' inside '%s' block", var.interface, iface_block->interface));
 237                 else if(scope==STRUCT || scope==FUNCTION)
 238                         error(var, format("Interface qualifier not allowed on %s", descr));
 239         }
 240
 241         TypeDeclaration *type = var.type_declaration;
 242         BasicTypeDeclaration::Kind kind = BasicTypeDeclaration::ALIAS;
 243         while(BasicTypeDeclaration *basic = dynamic_cast<BasicTypeDeclaration *>(type))
 244         {
 245                 kind = basic->kind;
 246                 type = basic->base_type;
 247         }
 248         if(dynamic_cast<ImageTypeDeclaration *>(type))
 249         {
 250                 if(scope!=GLOBAL && scope!=FUNCTION_PARAM)
 251                         error(var, format("Type '%s' not allowed on %s", type->name, descr));
 252                 else if(scope==GLOBAL && var.interface!="uniform")
 253                         error(var, format("Type '%s' only allowed with uniform interface", type->name));
 254         }
 255         else if(kind==BasicTypeDeclaration::VOID)
 256                 error(var, "Type 'void' not allowed on variable");
 257         else if(kind==BasicTypeDeclaration::BOOL && var.source!=BUILTIN_SOURCE)
 258         {
 259                 if(scope==INTERFACE_BLOCK)
 260                         error(var, "Type 'bool' not allowed in an interface block");
 261                 else if(!var.interface.empty())
 262                         error(var, "Type 'bool' not allowed on interface variable");
 263         }
 264
 265         if(var.init_expression)
 266         {
 267                 if(scope==GLOBAL && !var.constant)
 268                         error(var, format("Initializer not allowed on non-constant %s", descr));
 269                 else if(scope!=GLOBAL && scope!=FUNCTION)
 270                         error(var, format("Initializer not allowed on %s", descr));
 271                 else
 272                         var.init_expression->visit(*this);
 273         }
 274 }
 275
 276 void DeclarationValidator::visit(InterfaceBlock &iface)
 277 {
 278         SetForScope<ScopeType> set_scope(scope, INTERFACE_BLOCK);
 279         SetForScope<InterfaceBlock *> set_iface(iface_block, &iface);
 280
 281         if(stage->type==Stage::VERTEX && iface.interface=="in")
 282                 error(iface, "Interface block not allowed on vertex shader input");
 283         else if(stage->type==Stage::FRAGMENT && iface.interface=="out")
 284                 error(iface, "Interface block not allowed on fragment shader output");
 285
 286         TraversingVisitor::visit(iface);
 287         if(iface.struct_declaration)
 288                 iface.struct_declaration->visit(*this);
 289 }
 290
 291 void DeclarationValidator::visit(FunctionDeclaration &func)
 292 {
 293         SetForScope<ScopeType> set_scope(scope, FUNCTION_PARAM);
 294         for(const RefPtr<VariableDeclaration> &p: func.parameters)
 295                 p->visit(*this);
 296         scope = FUNCTION;
 297         func.body.visit(*this);
 298 }
 299
 300
 301 void IdentifierValidator::multiple_definition(const string &name, Statement &statement, Statement &previous)
 302 {
 303         error(statement, format("Multiple definition of %s", name));
 304         add_info(previous, "Previous definition is here");
 305 }
 306
 307 Statement *IdentifierValidator::find_definition(const string &name)
 308 {
 309         BlockDeclarationMap *decls = &declarations[current_block];
 310         auto i = decls->find(name);
 311         if(i==decls->end() && anonymous_block)
 312         {
 313                 decls = &declarations[current_block->parent];
 314                 i = decls->find(name);
 315         }
 316         return (i!=decls->end() ? i->second : 0);
 317 }
 318
 319 void IdentifierValidator::check_definition(const string &name, Statement &statement)
 320 {
 321         if(Statement *previous = find_definition(name))
 322                 multiple_definition(format("'%s'", name), statement, *previous);
 323         else
 324                 record_definition(name, statement);
 325 }
 326
 327 void IdentifierValidator::record_definition(const string &name, Statement &statement)
 328 {
 329         declarations[current_block].insert(make_pair(name, &statement));
 330         if(anonymous_block)
 331                 declarations[current_block->parent].insert(make_pair(name, &statement));
 332 }
 333
 334 void IdentifierValidator::visit(TypeDeclaration &type)
 335 {
 336         check_definition(type.name, type);
 337 }
 338
 339 void IdentifierValidator::visit(StructDeclaration &strct)
 340 {
 341         check_definition(strct.name, strct);
 342         TraversingVisitor::visit(strct);
 343 }
 344
 345 void IdentifierValidator::visit(VariableDeclaration &var)
 346 {
 347         check_definition(var.name, var);
 348         TraversingVisitor::visit(var);
 349 }
 350
 351 void IdentifierValidator::visit(InterfaceBlock &iface)
 352 {
 353         string key = format("%s %s", iface.interface, iface.block_name);
 354         auto i = interface_blocks.find(key);
 355         if(i!=interface_blocks.end())
 356                 multiple_definition(format("interface block '%s %s'", iface.interface, iface.block_name), iface, *i->second);
 357         else
 358                 interface_blocks.insert(make_pair(key, &iface));
 359
 360         if(Statement *previous = find_definition(iface.block_name))
 361         {
 362                 if(!dynamic_cast<InterfaceBlock *>(previous))
 363                         multiple_definition(format("'%s'", iface.block_name), iface, *previous);
 364         }
 365         else
 366                 record_definition(iface.block_name, iface);
 367
 368         if(!iface.instance_name.empty())
 369                 check_definition(iface.instance_name, iface);
 370
 371         if(iface.instance_name.empty() && iface.struct_declaration)
 372         {
 373                 // Inject anonymous interface block members into the global scope
 374                 for(const auto &kvp: iface.struct_declaration->members.variables)
 375                         check_definition(kvp.first, *kvp.second);
 376         }
 377 }
 378
 379 void IdentifierValidator::visit(FunctionDeclaration &func)
 380 {
 381         string key = func.name+func.signature;
 382         auto i = overloaded_functions.find(key);
 383         if(i==overloaded_functions.end())
 384                 overloaded_functions.insert(make_pair(key, &func));
 385         else if(func.return_type_declaration && i->second->return_type_declaration!=func.return_type_declaration)
 386         {
 387                 error(func, format("Conflicting return type '%s' for function '%s'", func.return_type_declaration->name, func.name));
 388                 if(i->second->return_type_declaration)
 389                         add_info(*i->second, format("Previously declared as returning '%s'", i->second->return_type_declaration->name));
 390         }
 391
 392         if(Statement *previous = find_definition(func.name))
 393         {
 394                 if(!dynamic_cast<FunctionDeclaration *>(previous))
 395                         multiple_definition(format("'%s'", func.name), func, *previous);
 396         }
 397         else
 398                 record_definition(func.name, func);
 399
 400         if(func.definition==&func)
 401                 check_definition(func.name+func.signature, func);
 402
 403         TraversingVisitor::visit(func);
 404 }
 405
 406
 407 void ReferenceValidator::visit(BasicTypeDeclaration &type)
 408 {
 409         if(!type.base.empty() && !type.base_type)
 410                 error(type, format("Use of undeclared type '%s'", type.base));
 411 }
 412
 413 void ReferenceValidator::visit(ImageTypeDeclaration &type)
 414 {
 415         if(!type.base.empty() && !type.base_type)
 416                 error(type, format("Use of undeclared type '%s'", type.base));
 417 }
 418
 419 void ReferenceValidator::visit(VariableReference &var)
 420 {
 421         if(!var.declaration)
 422                 error(var, format("Use of undeclared variable '%s'", var.name));
 423         else if(stage->type!=Stage::VERTEX && var.declaration->interface=="in" && var.name.compare(0, 3, "gl_") && !var.declaration->linked_declaration)
 424                 error(var, format("Use of unlinked input variable '%s'", var.name));
 425 }
 426
 427 void ReferenceValidator::visit(MemberAccess &memacc)
 428 {
 429         if(memacc.left->type && !memacc.declaration)
 430                 error(memacc, format("Use of undeclared member '%s'", memacc.member));
 431         TraversingVisitor::visit(memacc);
 432 }
 433
 434 void ReferenceValidator::visit(InterfaceBlockReference &iface)
 435 {
 436         /* An interface block reference without a declaration should be impossible
 437         since references are generated based on existing declarations. */
 438         if(!iface.declaration)
 439                 error(iface, format("Use of undeclared interface block '%s'", iface.name));
 440         else if(stage->type!=Stage::VERTEX && iface.declaration->interface=="in" && !iface.declaration->linked_block)
 441                 error(iface, format("Use of unlinked input block '%s'", iface.name));
 442 }
 443
 444 void ReferenceValidator::visit(FunctionCall &call)
 445 {
 446         if((!call.constructor && !call.declaration) || (call.constructor && !call.type))
 447         {
 448                 bool have_declaration = call.constructor;
 449                 if(!call.constructor)
 450                 {
 451                         auto i = stage->functions.lower_bound(call.name);
 452                         have_declaration = (i!=stage->functions.end() && i->second->name==call.name);
 453                 }
 454
 455                 if(have_declaration)
 456                 {
 457                         bool valid_types = true;
 458                         string signature;
 459                         for(auto j=call.arguments.begin(); (valid_types && j!=call.arguments.end()); ++j)
 460                         {
 461                                 if((*j)->type)
 462                                         append(signature, ", ", (*j)->type->name);
 463                                 else
 464                                         valid_types = false;
 465                         }
 466
 467                         if(valid_types)
 468                                 error(call, format("No matching %s found for '%s(%s)'", (call.constructor ? "constructor" : "overload"), call.name, signature));
 469                 }
 470                 else
 471                         error(call, format("Call to undeclared function '%s'", call.name));
 472         }
 473         TraversingVisitor::visit(call);
 474 }
 475
 476 void ReferenceValidator::visit(VariableDeclaration &var)
 477 {
 478         if(!var.type_declaration)
 479                 error(var, format("Use of undeclared type '%s'", var.type));
 480         TraversingVisitor::visit(var);
 481 }
 482
 483 void ReferenceValidator::visit(InterfaceBlock &iface)
 484 {
 485         if(!iface.struct_declaration)
 486                 error(iface, format("Interface block '%s %s' lacks a struct declaration", iface.interface, iface.block_name));
 487         TraversingVisitor::visit(iface);
 488 }
 489
 490 void ReferenceValidator::visit(FunctionDeclaration &func)
 491 {
 492         if(!func.return_type_declaration)
 493                 error(func, format("Use of undeclared type '%s'", func.return_type));
 494         TraversingVisitor::visit(func);
 495 }
 496
 497
 498 void ExpressionValidator::visit(VariableReference &var)
 499 {
 500         if(var.declaration && constant_expression && !var.declaration->constant)
 501                 error(var, format("Reference to non-constant variable '%s' in a constant expression", var.name));
 502 }
 503
 504 void ExpressionValidator::visit(InterfaceBlockReference &iface)
 505 {
 506         if(constant_expression)
 507                 error(iface, format("Reference to interface block '%s' in a constant expression", iface.name));
 508 }
 509
 510 void ExpressionValidator::visit(Swizzle &swizzle)
 511 {
 512         unsigned size = 0;
 513         if(BasicTypeDeclaration *basic = dynamic_cast<BasicTypeDeclaration *>(swizzle.left->type))
 514         {
 515                 if(basic->kind==BasicTypeDeclaration::INT || basic->kind==BasicTypeDeclaration::FLOAT)
 516                         size = 1;
 517                 else if(basic->kind==BasicTypeDeclaration::VECTOR)
 518                         size = basic->size;
 519         }
 520
 521         if(size)
 522         {
 523                 static const char component_names[] = { 'x', 'y', 'z', 'w', 'r', 'g', 'b', 'a', 's', 't', 'p', 'q' };
 524                 int flavour = -1;
 525                 for(unsigned i=0; i<swizzle.count; ++i)
 526                 {
 527                         unsigned component_flavour = (find(component_names, component_names+12, swizzle.component_group[i])-component_names)/4;
 528                         if(flavour==-1)
 529                                 flavour = component_flavour;
 530                         else if(flavour>=0 && component_flavour!=static_cast<unsigned>(flavour))
 531                         {
 532                                 error(swizzle, format("Flavour of swizzle component '%c' is inconsistent with '%c'",
 533                                         swizzle.component_group[i], swizzle.component_group[0]));
 534                                 flavour = -2;
 535                         }
 536
 537                         if(swizzle.components[i]>=size)
 538                                 error(swizzle, format("Access to component '%c' which is not present in '%s'",
 539                                         swizzle.component_group[i], swizzle.left->type->name));
 540                 }
 541         }
 542         else if(swizzle.left->type)
 543                 error(swizzle, format("Swizzle applied to '%s' which is neither a scalar nor a vector", swizzle.left->type->name));
 544
 545         TraversingVisitor::visit(swizzle);
 546 }
 547
 548 void ExpressionValidator::visit(UnaryExpression &unary)
 549 {
 550         if(unary.expression->type)
 551         {
 552                 if(!unary.type)
 553                         error(unary, format("No matching operator '%s' found for '%s'", unary.oper->token, unary.expression->type->name));
 554                 else if(unary.oper->token[1]=='+' || unary.oper->token[1]=='-')
 555                 {
 556                         if(constant_expression)
 557                                 error(unary, format("Use of '%s' in a constant expression", unary.oper->token));
 558                         else if(!unary.expression->lvalue)
 559                                 error(unary, format("Operand of '%s' is not an lvalue", unary.oper->token));
 560                 }
 561         }
 562         TraversingVisitor::visit(unary);
 563 }
 564
 565 void ExpressionValidator::visit(BinaryExpression &binary)
 566 {
 567         if(!binary.type && binary.left->type && binary.right->type)
 568         {
 569                 if(binary.oper->token[0]=='[')
 570                         error(binary, format("Can't index element of '%s' with '%s'",
 571                                 binary.left->type->name, binary.right->type->name));
 572                 else
 573                         error(binary, format("No matching operator '%s' found for '%s' and '%s'",
 574                                 binary.oper->token, binary.left->type->name, binary.right->type->name));
 575         }
 576         TraversingVisitor::visit(binary);
 577 }
 578
 579 void ExpressionValidator::visit(Assignment &assign)
 580 {
 581         if(assign.left->type)
 582         {
 583                 if(constant_expression)
 584                         error(assign, "Assignment in constant expression");
 585                 else if(!assign.left->lvalue)
 586                         error(assign, "Target of assignment is not an lvalue");
 587                 if(assign.right->type)
 588                 {
 589                         if(assign.oper->token[0]!='=')
 590                         {
 591                                 if(!assign.type)
 592                                         error(assign, format("No matching operator '%s' found for '%s' and '%s'",
 593                                                 string(assign.oper->token, strlen(assign.oper->token)-1), assign.left->type->name, assign.right->type->name));
 594                         }
 595                         else if(assign.left->type!=assign.right->type)
 596                                 error(assign, format("Assignment to variable of type '%s' from expression of incompatible type '%s'",
 597                                         assign.left->type->name, assign.right->type->name));
 598                 }
 599         }
 600         TraversingVisitor::visit(assign);
 601 }
 602
 603 void ExpressionValidator::visit(TernaryExpression &ternary)
 604 {
 605         if(ternary.condition->type)
 606         {
 607                 BasicTypeDeclaration *basic_cond = dynamic_cast<BasicTypeDeclaration *>(ternary.condition->type);
 608                 if(!basic_cond || basic_cond->kind!=BasicTypeDeclaration::BOOL)
 609                         error(ternary, "Ternary operator condition is not a boolean");
 610                 else if(!ternary.type && ternary.true_expr->type && ternary.false_expr->type)
 611                         error(ternary, format("Ternary operator has incompatible types '%s' and '%s'",
 612                                 ternary.true_expr->type->name, ternary.false_expr->type->name));
 613         }
 614         TraversingVisitor::visit(ternary);
 615 }
 616
 617 void ExpressionValidator::visit(VariableDeclaration &var)
 618 {
 619         if(var.init_expression && var.init_expression->type && var.type_declaration && var.init_expression->type!=var.type_declaration)
 620                 error(var, format("Initializing a variable of type '%s' with an expression of incompatible type '%s'",
 621                         var.type_declaration->name, var.init_expression->type->name));
 622
 623         if(var.layout)
 624                 var.layout->visit(*this);
 625         if(var.init_expression)
 626         {
 627                 SetFlag set_const(constant_expression, var.constant);
 628                 TraversingVisitor::visit(var.init_expression);
 629         }
 630         if(var.array_size)
 631         {
 632                 SetFlag set_const(constant_expression);
 633                 TraversingVisitor::visit(var.array_size);
 634         }
 635 }
 636
 637 void ExpressionValidator::visit(FunctionDeclaration &func)
 638 {
 639         SetForScope<FunctionDeclaration *> set_func(current_function, &func);
 640         TraversingVisitor::visit(func);
 641 }
 642
 643 void ExpressionValidator::visit(Conditional &cond)
 644 {
 645         if(cond.condition->type)
 646         {
 647                 BasicTypeDeclaration *basic_cond = dynamic_cast<BasicTypeDeclaration *>(cond.condition->type);
 648                 if(!basic_cond || basic_cond->kind!=BasicTypeDeclaration::BOOL)
 649                         error(cond, "Condition is not a boolean");
 650         }
 651         TraversingVisitor::visit(cond);
 652 }
 653
 654 void ExpressionValidator::visit(Iteration &iter)
 655 {
 656         if(iter.condition->type)
 657         {
 658                 BasicTypeDeclaration *basic_cond = dynamic_cast<BasicTypeDeclaration *>(iter.condition->type);
 659                 if(!basic_cond || basic_cond->kind!=BasicTypeDeclaration::BOOL)
 660                         error(iter, "Loop condition is not a boolean");
 661         }
 662         TraversingVisitor::visit(iter);
 663 }
 664
 665 void ExpressionValidator::visit(Return &ret)
 666 {
 667         if(current_function && current_function->return_type_declaration)
 668         {
 669                 TypeDeclaration *return_type = current_function->return_type_declaration;
 670                 BasicTypeDeclaration *basic_return = dynamic_cast<BasicTypeDeclaration *>(return_type);
 671                 if(ret.expression)
 672                 {
 673                         if(ret.expression->type && ret.expression->type!=return_type)
 674                                 error(ret, format("Return expression type '%s' is incompatible with declared return type '%s'",
 675                                         ret.expression->type->name, return_type->name));
 676                 }
 677                 else if(!basic_return || basic_return->kind!=BasicTypeDeclaration::VOID)
 678                         error(ret, "Return statement without an expression in a function not returning 'void'");
 679         }
 680
 681         TraversingVisitor::visit(ret);
 682 }
 683
 684
 685 void FlowControlValidator::visit(Block &block)
 686 {
 687         for(const RefPtr<Statement> &s: block.body)
 688         {
 689                 if(!reachable)
 690                 {
 691                         diagnose(*s, Diagnostic::WARN, "Unreachable code detected");
 692                         break;
 693                 }
 694                 s->visit(*this);
 695         }
 696 }
 697
 698 void FlowControlValidator::visit(FunctionDeclaration &func)
 699 {
 700         func.body.visit(*this);
 701
 702         if(func.definition==&func && func.return_type_declaration)
 703         {
 704                 const BasicTypeDeclaration *basic_ret = dynamic_cast<const BasicTypeDeclaration *>(func.return_type_declaration);
 705                 if(reachable && (!basic_ret || basic_ret->kind!=BasicTypeDeclaration::VOID))
 706                         error(func, "Missing return statement at the end of a function not returning 'void'");
 707         }
 708         reachable = true;
 709 }
 710
 711 void FlowControlValidator::visit(Conditional &cond)
 712 {
 713         cond.body.visit(*this);
 714         bool reachable_if_true = reachable;
 715         reachable = true;
 716         cond.else_body.visit(*this);
 717         reachable |= reachable_if_true;
 718 }
 719
 720 void FlowControlValidator::visit(Iteration &iter)
 721 {
 722         iter.body.visit(*this);
 723         reachable = true;
 724 }
 725
 726
 727 int StageInterfaceValidator::get_location(const Layout &layout)
 728 {
 729         return get_layout_value(layout, "location", -1);
 730 }
 731
 732 void StageInterfaceValidator::visit(VariableDeclaration &var)
 733 {
 734         int location = (var.layout ? get_location(*var.layout) : -1);
 735         if(var.interface=="in" && var.linked_declaration)
 736         {
 737                 const Layout *linked_layout = var.linked_declaration->layout.get();
 738                 int linked_location = (linked_layout ? get_location(*linked_layout) : -1);
 739                 if(linked_location!=location)
 740                 {
 741                         error(var, format("Mismatched location %d for 'in %s'", location, var.name));
 742                         add_info(*var.linked_declaration, format("Linked to 'out %s' with location %d",
 743                                 var.linked_declaration->name, linked_location));
 744                 }
 745                 if(var.type_declaration && var.linked_declaration->type_declaration)
 746                 {
 747                         TypeDeclaration *type = var.type_declaration;
 748                         if(stage->type==Stage::GEOMETRY)
 749                         {
 750                                 if(const BasicTypeDeclaration *basic = dynamic_cast<const BasicTypeDeclaration *>(type))
 751                                         if(basic->kind==BasicTypeDeclaration::ARRAY && basic->base_type)
 752                                                 type = basic->base_type;
 753                         }
 754                         if(!TypeComparer().apply(*type, *var.linked_declaration->type_declaration))
 755                         {
 756                                 error(var, format("Mismatched type '%s' for 'in %s'", type->name, var.name));
 757                                 add_info(*var.linked_declaration, format("Linked to 'out %s' with type '%s'",
 758                                         var.linked_declaration->name, var.linked_declaration->type_declaration->name));
 759                         }
 760                 }
 761         }
 762
 763         if(location>=0 && !var.interface.empty())
 764         {
 765                 map<unsigned, VariableDeclaration *> &used = used_locations[var.interface];
 766
 767                 unsigned loc_count = LocationCounter().apply(var);
 768                 for(unsigned i=0; i<loc_count; ++i)
 769                 {
 770                         auto j = used.find(location+i);
 771                         if(j!=used.end())
 772                         {
 773                                 error(var, format("Overlapping location %d for '%s %s'", location+i, var.interface, var.name));
 774                                 add_info(*j->second, format("Previously used here for '%s %s'", j->second->interface, j->second->name));
 775                         }
 776                         else
 777                                 used[location+i] = &var;
 778                 }
 779         }
 780 }
 781
 782
 783 void GlobalInterfaceValidator::apply(Module &module)
 784 {
 785         for(Stage &s: module.stages)
 786         {
 787                 stage = &s;
 788                 s.content.visit(*this);
 789         }
 790 }
 791
 792 void GlobalInterfaceValidator::check_uniform(const Uniform &uni)
 793 {
 794         auto i = used_names.find(uni.name);
 795         if(i!=used_names.end())
 796         {
 797                 if(uni.location>=0 && i->second->location>=0 && i->second->location!=uni.location)
 798                 {
 799                         error(*uni.node, format("Mismatched location %d for uniform '%s'", uni.location, uni.name));
 800                         add_info(*i->second->node, format("Previously declared here with location %d", i->second->location));
 801                 }
 802                 if(uni.bind_point>=0 && i->second->bind_point>=0 && i->second->bind_point!=uni.bind_point)
 803                 {
 804                         error(*uni.node, format("Mismatched binding %d for uniform '%s'", uni.bind_point, uni.name));
 805                         add_info(*i->second->node, format("Previously declared here with binding %d", i->second->bind_point));
 806                 }
 807                 if(uni.type && i->second->type && !TypeComparer().apply(*uni.type, *i->second->type))
 808                 {
 809                         string type_name = (dynamic_cast<const StructDeclaration *>(uni.type) ?
 810                                 "structure" : format("type '%s'", uni.type->name));
 811                         error(*uni.node, format("Mismatched %s for uniform '%s'", type_name, uni.name));
 812
 813                         string message = "Previously declared here";
 814                         if(!dynamic_cast<const StructDeclaration *>(i->second->type))
 815                                 message += format(" with type '%s'", i->second->type->name);
 816                         add_info(*i->second->node, message);
 817                 }
 818         }
 819         else
 820                 used_names.insert(make_pair(uni.name, &uni));
 821
 822         if(uni.location>=0)
 823         {
 824                 auto j = used_locations.find(uni.location);
 825                 if(j!=used_locations.end())
 826                 {
 827                         if(j->second->name!=uni.name)
 828                         {
 829                                 error(*uni.node, format("Overlapping location %d for '%s'", uni.location, uni.name));
 830                                 add_info(*j->second->node, format("Previously used here for '%s'", j->second->name));
 831                         }
 832                 }
 833                 else
 834                 {
 835                         for(unsigned k=0; k<uni.loc_count; ++k)
 836                                 used_locations.insert(make_pair(uni.location+k, &uni));
 837                 }
 838         }
 839
 840         if(uni.bind_point>=0)
 841         {
 842                 map<unsigned, const Uniform *> &used = used_bindings[uni.desc_set];
 843                 auto j = used.find(uni.bind_point);
 844                 if(j!=used.end())
 845                 {
 846                         if(j->second->name!=uni.name)
 847                         {
 848                                 error(*uni.node, format("Overlapping binding %d for '%s'", uni.bind_point, uni.name));
 849                                 add_info(*j->second->node, format("Previously used here for '%s'", j->second->name));
 850                         }
 851                 }
 852                 else
 853                         used.insert(make_pair(uni.bind_point, &uni));
 854         }
 855 }
 856
 857 void GlobalInterfaceValidator::visit(VariableDeclaration &var)
 858 {
 859         if(var.interface=="uniform")
 860         {
 861                 Uniform uni;
 862                 uni.node = &var;
 863                 uni.type = var.type_declaration;
 864                 uni.name = var.name;
 865                 if(var.layout)
 866                 {
 867                         uni.location = get_layout_value(*var.layout, "location");
 868                         uni.loc_count = LocationCounter().apply(var);
 869                         uni.desc_set = get_layout_value(*var.layout, "set", 0);
 870                         uni.bind_point = get_layout_value(*var.layout, "binding");
 871                 }
 872
 873                 uniforms.push_back(uni);
 874                 check_uniform(uniforms.back());
 875         }
 876 }
 877
 878 void GlobalInterfaceValidator::visit(InterfaceBlock &iface)
 879 {
 880         if(iface.interface=="uniform")
 881         {
 882                 Uniform uni;
 883                 uni.node = &iface;
 884                 uni.type = iface.struct_declaration;
 885                 uni.name = iface.block_name;
 886                 if(iface.layout)
 887                 {
 888                         uni.desc_set = get_layout_value(*iface.layout, "set", 0);
 889                         uni.bind_point = get_layout_value(*iface.layout, "binding");
 890                 }
 891
 892                 uniforms.push_back(uni);
 893                 check_uniform(uniforms.back());
 894         }
 895 }
 896
 897 } // namespace SL
 898 } // namespace GL
 899 } // namespace Msp