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Refactor and improve unused variable detection in ProgramCompiler
[libs/gl.git] / 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 "resources.h"
8 #include "shader.h"
9
10 using namespace std;
11
12 namespace {
13
14 const char builtins_src[] =
15         "////// vertex\n"
16         "out gl_PerVertex {\n"
17         "  vec4 gl_Position;\n"
18         "  float gl_ClipDistance[];\n"
19         "};"
20         "////// geometry\n"
21         "in gl_PerVertex {\n"
22         "  vec4 gl_Position;\n"
23         "  float gl_ClipDistance[];\n"
24         "} gl_in[];\n"
25         "out gl_PerVertex {\n"
26         "  vec4 gl_Position;\n"
27         "  float gl_ClipDistance[];\n"
28         "};\n";
29
30 }
31
32 namespace Msp {
33 namespace GL {
34
35 using namespace ProgramSyntax;
36
37 ProgramCompiler::ProgramCompiler():
38         resources(0),
39         module(0)
40 { }
41
42 void ProgramCompiler::compile(const string &source)
43 {
44         resources = 0;
45         module = &parser.parse(source);
46         process();
47 }
48
49 void ProgramCompiler::compile(IO::Base &io, Resources *res)
50 {
51         resources = res;
52         module = &parser.parse(io);
53         process();
54 }
55
56 void ProgramCompiler::add_shaders(Program &program)
57 {
58         if(!module)
59                 throw invalid_operation("ProgramCompiler::add_shaders");
60
61         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
62         {
63                 if(i->type==VERTEX)
64                 {
65                         program.attach_shader_owned(new VertexShader(apply<Formatter>(*i)));
66                         for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
67                                 program.bind_attribute(j->second, j->first);
68                 }
69                 else if(i->type==GEOMETRY)
70                         program.attach_shader_owned(new GeometryShader(apply<Formatter>(*i)));
71                 else if(i->type==FRAGMENT)
72                 {
73                         program.attach_shader_owned(new FragmentShader(apply<Formatter>(*i)));
74                         for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
75                                 program.bind_fragment_data(j->second, j->first);
76                 }
77         }
78 }
79
80 Module *ProgramCompiler::create_builtins_module()
81 {
82         ProgramParser parser;
83         Module *module = new Module(parser.parse(builtins_src));
84         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
85         {
86                 VariableResolver resolver;
87                 i->content.visit(resolver);
88                 for(map<string, VariableDeclaration *>::iterator j=i->content.variables.begin(); j!=i->content.variables.end(); ++j)
89                         j->second->linked_declaration = j->second;
90         }
91         return module;
92 }
93
94 Module &ProgramCompiler::get_builtins_module()
95 {
96         static RefPtr<Module> builtins_module = create_builtins_module();
97         return *builtins_module;
98 }
99
100 Stage *ProgramCompiler::get_builtins(StageType type)
101 {
102         Module &module = get_builtins_module();
103         for(list<Stage>::iterator i=module.stages.begin(); i!=module.stages.end(); ++i)
104                 if(i->type==type)
105                         return &*i;
106         return 0;
107 }
108
109 void ProgramCompiler::process()
110 {
111         list<Import *> imports = apply<NodeGatherer<Import> >(module->shared);
112         for(list<Import *>::iterator i=imports.end(); i!=imports.begin(); )
113                 import((*--i)->module);
114         apply<NodeRemover>(module->shared, set<Node *>(imports.begin(), imports.end()));
115
116         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
117                 generate(*i);
118         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); )
119         {
120                 if(optimize(*i))
121                         i = module->stages.begin();
122                 else
123                         ++i;
124         }
125 }
126
127 void ProgramCompiler::import(const string &name)
128 {
129         string fn = name+".glsl";
130         RefPtr<IO::Seekable> io = (resources ? resources->open_raw(fn) : Resources::get_builtins().open(fn));
131         if(!io)
132                 throw runtime_error(format("module %s not found", name));
133         ProgramParser import_parser;
134         Module &imported_module = import_parser.parse(*io);
135
136         inject_block(module->shared.content, imported_module.shared.content);
137         apply<DeclarationCombiner>(module->shared);
138         for(list<Stage>::iterator i=imported_module.stages.begin(); i!=imported_module.stages.end(); ++i)
139         {
140                 list<Stage>::iterator j;
141                 for(j=module->stages.begin(); (j!=module->stages.end() && j->type<i->type); ++j) ;
142                 if(j==module->stages.end() || j->type>i->type)
143                 {
144                         j = module->stages.insert(j, *i);
145                         list<Stage>::iterator k = j;
146                         if(++k!=module->stages.end())
147                                 k->previous = &*j;
148                         if(j!=module->stages.begin())
149                                 j->previous = &*--(k=j);
150                 }
151                 else
152                 {
153                         inject_block(j->content, i->content);
154                         apply<DeclarationCombiner>(*j);
155                 }
156         }
157 }
158
159 void ProgramCompiler::generate(Stage &stage)
160 {
161         inject_block(stage.content, module->shared.content);
162
163         apply<FunctionResolver>(stage);
164         apply<VariableResolver>(stage);
165         apply<InterfaceGenerator>(stage);
166         apply<VariableResolver>(stage);
167         apply<VariableRenamer>(stage);
168         apply<DeclarationReorderer>(stage);
169         apply<LegacyConverter>(stage);
170 }
171
172 bool ProgramCompiler::optimize(Stage &stage)
173 {
174         apply<ConstantConditionEliminator>(stage);
175
176         set<FunctionDeclaration *> inlineable = apply<InlineableFunctionLocator>(stage);
177         apply<FunctionInliner>(stage, inlineable);
178
179         set<Node *> unused = apply<UnusedVariableLocator>(stage);
180         set<Node *> unused2 = apply<UnusedFunctionLocator>(stage);
181         unused.insert(unused2.begin(), unused2.end());
182         apply<NodeRemover>(stage, unused);
183
184         return !unused.empty();
185 }
186
187 void ProgramCompiler::inject_block(Block &target, const Block &source)
188 {
189         list<RefPtr<Node> >::iterator insert_point = target.body.begin();
190         for(list<RefPtr<Node> >::const_iterator i=source.body.begin(); i!=source.body.end(); ++i)
191                 target.body.insert(insert_point, (*i)->clone());
192 }
193
194 template<typename T>
195 typename T::ResultType ProgramCompiler::apply(Stage &stage)
196 {
197         T visitor;
198         visitor.apply(stage);
199         return visitor.get_result();
200 }
201
202 template<typename T, typename A>
203 typename T::ResultType ProgramCompiler::apply(Stage &stage, const A &arg)
204 {
205         T visitor(arg);
206         visitor.apply(stage);
207         return visitor.get_result();
208 }
209
210
211 ProgramCompiler::Visitor::Visitor():
212         stage(0)
213 { }
214
215 void ProgramCompiler::Visitor::apply(Stage &s)
216 {
217         SetForScope<Stage *> set(stage, &s);
218         stage->content.visit(*this);
219 }
220
221
222 ProgramCompiler::Formatter::Formatter():
223         indent(0),
224         parameter_list(false),
225         else_if(0)
226 { }
227
228 void ProgramCompiler::Formatter::apply(ProgramSyntax::Stage &s)
229 {
230         const Version &ver = s.required_version;
231         if(ver.major)
232                 formatted += format("#version %d%d\n", ver.major, ver.minor);
233         Visitor::apply(s);
234 }
235
236 void ProgramCompiler::Formatter::visit(Literal &literal)
237 {
238         formatted += literal.token;
239 }
240
241 void ProgramCompiler::Formatter::visit(ParenthesizedExpression &parexpr)
242 {
243         formatted += '(';
244         parexpr.expression->visit(*this);
245         formatted += ')';
246 }
247
248 void ProgramCompiler::Formatter::visit(VariableReference &var)
249 {
250         formatted += var.name;
251 }
252
253 void ProgramCompiler::Formatter::visit(MemberAccess &memacc)
254 {
255         memacc.left->visit(*this);
256         formatted += format(".%s", memacc.member);
257 }
258
259 void ProgramCompiler::Formatter::visit(UnaryExpression &unary)
260 {
261         if(unary.prefix)
262                 formatted += unary.oper;
263         unary.expression->visit(*this);
264         if(!unary.prefix)
265                 formatted += unary.oper;
266 }
267
268 void ProgramCompiler::Formatter::visit(BinaryExpression &binary)
269 {
270         binary.left->visit(*this);
271         formatted += binary.oper;
272         binary.right->visit(*this);
273         formatted += binary.after;
274 }
275
276 void ProgramCompiler::Formatter::visit(Assignment &assign)
277 {
278         assign.left->visit(*this);
279         formatted += format(" %s ", assign.oper);
280         assign.right->visit(*this);
281 }
282
283 void ProgramCompiler::Formatter::visit(FunctionCall &call)
284 {
285         formatted += format("%s(", call.name);
286         for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
287         {
288                 if(i!=call.arguments.begin())
289                         formatted += ", ";
290                 (*i)->visit(*this);
291         }
292         formatted += ')';
293 }
294
295 void ProgramCompiler::Formatter::visit(ExpressionStatement &expr)
296 {
297         expr.expression->visit(*this);
298         formatted += ';';
299 }
300
301 void ProgramCompiler::Formatter::visit(Block &block)
302 {
303         if(else_if)
304                 --else_if;
305
306         unsigned brace_indent = indent;
307         bool use_braces = (block.use_braces || (indent && block.body.size()!=1));
308         if(use_braces)
309                 formatted += format("%s{\n", string(brace_indent*2, ' '));
310
311         SetForScope<unsigned> set(indent, indent+(indent>0 || use_braces));
312         string spaces(indent*2, ' ');
313         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
314         {
315                 if(i!=block.body.begin())
316                         formatted += '\n';
317                 formatted += spaces;
318                 (*i)->visit(*this);
319                 else_if = 0;
320         }
321
322         if(use_braces)
323                 formatted += format("\n%s}", string(brace_indent*2, ' '));
324 }
325
326 void ProgramCompiler::Formatter::visit(Import &import)
327 {
328         formatted += format("import %s;", import.module);
329 }
330
331 void ProgramCompiler::Formatter::visit(Layout &layout)
332 {
333         formatted += "layout(";
334         for(vector<Layout::Qualifier>::const_iterator i=layout.qualifiers.begin(); i!=layout.qualifiers.end(); ++i)
335         {
336                 if(i!=layout.qualifiers.begin())
337                         formatted += ", ";
338                 formatted += i->identifier;
339                 if(!i->value.empty())
340                         formatted += format("=%s", i->value);
341         }
342         formatted += ')';
343 }
344
345 void ProgramCompiler::Formatter::visit(InterfaceLayout &layout)
346 {
347         layout.layout.visit(*this);
348         formatted += format(" %s;", layout.interface);
349 }
350
351 void ProgramCompiler::Formatter::visit(StructDeclaration &strct)
352 {
353         formatted += format("struct %s\n", strct.name);
354         strct.members.visit(*this);
355         formatted += ';';
356 }
357
358 void ProgramCompiler::Formatter::visit(VariableDeclaration &var)
359 {
360         if(var.layout)
361         {
362                 var.layout->visit(*this);
363                 formatted += ' ';
364         }
365         if(var.constant)
366                 formatted += "const ";
367         if(!var.sampling.empty())
368                 formatted += format("%s ", var.sampling);
369         if(!var.interface.empty() && var.interface!=block_interface)
370                 formatted += format("%s ", var.interface);
371         formatted += format("%s %s", var.type, var.name);
372         if(var.array)
373         {
374                 formatted += '[';
375                 if(var.array_size)
376                         var.array_size->visit(*this);
377                 formatted += ']';
378         }
379         if(var.init_expression)
380         {
381                 formatted += " = ";
382                 var.init_expression->visit(*this);
383         }
384         if(!parameter_list)
385                 formatted += ';';
386 }
387
388 void ProgramCompiler::Formatter::visit(InterfaceBlock &iface)
389 {
390         SetForScope<string> set(block_interface, iface.interface);
391         formatted += format("%s %s\n", iface.interface, iface.name);
392         iface.members.visit(*this);
393         formatted += ';';
394 }
395
396 void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
397 {
398         formatted += format("%s %s(", func.return_type, func.name);
399         for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
400         {
401                 if(i!=func.parameters.begin())
402                         formatted += ", ";
403                 SetFlag set(parameter_list);
404                 (*i)->visit(*this);
405         }
406         formatted += ')';
407         if(func.definition==&func)
408         {
409                 formatted += '\n';
410                 func.body.visit(*this);
411         }
412         else
413                 formatted += ';';
414 }
415
416 void ProgramCompiler::Formatter::visit(Conditional &cond)
417 {
418         if(else_if)
419                 formatted.replace(formatted.rfind('\n'), string::npos, 1, ' ');
420
421         indent -= else_if;
422
423         formatted += "if(";
424         cond.condition->visit(*this);
425         formatted += ")\n";
426
427         cond.body.visit(*this);
428         if(!cond.else_body.body.empty())
429         {
430                 formatted += format("\n%selse\n", string(indent*2, ' '));
431                 SetForScope<unsigned> set(else_if, 2);
432                 cond.else_body.visit(*this);
433         }
434 }
435
436 void ProgramCompiler::Formatter::visit(Iteration &iter)
437 {
438         formatted += "for(";
439         iter.init_statement->visit(*this);
440         formatted += ' ';
441         iter.condition->visit(*this);
442         formatted += "; ";
443         iter.loop_expression->visit(*this);
444         formatted += ")\n";
445         iter.body.visit(*this);
446 }
447
448 void ProgramCompiler::Formatter::visit(Return &ret)
449 {
450         formatted += "return ";
451         ret.expression->visit(*this);
452         formatted += ';';
453 }
454
455 void ProgramCompiler::Formatter::visit(Jump &jump)
456 {
457         formatted += jump.keyword;
458         formatted += ';';
459 }
460
461
462 ProgramCompiler::DeclarationCombiner::DeclarationCombiner():
463         toplevel(true),
464         remove_node(false)
465 { }
466
467 void ProgramCompiler::DeclarationCombiner::visit(Block &block)
468 {
469         if(!toplevel)
470                 return;
471
472         SetForScope<bool> set(toplevel, false);
473         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
474         {
475                 remove_node = false;
476                 (*i)->visit(*this);
477                 if(remove_node)
478                         block.body.erase(i++);
479                 else
480                         ++i;
481         }
482 }
483
484 void ProgramCompiler::DeclarationCombiner::visit(FunctionDeclaration &func)
485 {
486         vector<FunctionDeclaration *> &decls = functions[func.name];
487         if(func.definition)
488         {
489                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
490                 {
491                         (*i)->definition = func.definition;
492                         (*i)->body.body.clear();
493                 }
494         }
495         decls.push_back(&func);
496 }
497
498 void ProgramCompiler::DeclarationCombiner::visit(VariableDeclaration &var)
499 {
500         VariableDeclaration *&ptr = variables[var.name];
501         if(ptr)
502         {
503                 ptr->type = var.type;
504                 if(var.init_expression)
505                         ptr->init_expression = var.init_expression;
506                 remove_node = true;
507         }
508         else
509                 ptr = &var;
510 }
511
512
513 ProgramCompiler::VariableResolver::VariableResolver():
514         anonymous(false),
515         record_target(false),
516         assignment_target(0),
517         self_referencing(false)
518 { }
519
520 void ProgramCompiler::VariableResolver::apply(Stage &s)
521 {
522         SetForScope<Stage *> set(stage, &s);
523         Stage *builtins = get_builtins(stage->type);
524         if(builtins)
525                 blocks.push_back(&builtins->content);
526         stage->content.visit(*this);
527         if(builtins)
528                 blocks.pop_back();
529 }
530
531 void ProgramCompiler::VariableResolver::visit(Block &block)
532 {
533         blocks.push_back(&block);
534         block.variables.clear();
535         TraversingVisitor::visit(block);
536         blocks.pop_back();
537 }
538
539 void ProgramCompiler::VariableResolver::visit(VariableReference &var)
540 {
541         var.declaration = 0;
542         type = 0;
543         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
544         {
545                 --i;
546                 map<string, VariableDeclaration *>::iterator j = (*i)->variables.find(var.name);
547                 if(j!=(*i)->variables.end())
548                 {
549                         var.declaration = j->second;
550                         type = j->second->type_declaration;
551                         break;
552                 }
553         }
554
555         if(record_target)
556         {
557                 if(assignment_target)
558                 {
559                         record_target = false;
560                         assignment_target = 0;
561                 }
562                 else
563                         assignment_target = var.declaration;
564         }
565         else if(var.declaration && var.declaration==assignment_target)
566                 self_referencing = true;
567 }
568
569 void ProgramCompiler::VariableResolver::visit(MemberAccess &memacc)
570 {
571         type = 0;
572         TraversingVisitor::visit(memacc);
573         memacc.declaration = 0;
574         if(type)
575         {
576                 map<string, VariableDeclaration *>::iterator i = type->members.variables.find(memacc.member);
577                 if(i!=type->members.variables.end())
578                 {
579                         memacc.declaration = i->second;
580                         type = i->second->type_declaration;
581                 }
582                 else
583                         type = 0;
584         }
585 }
586
587 void ProgramCompiler::VariableResolver::visit(BinaryExpression &binary)
588 {
589         if(binary.oper=="[")
590         {
591                 {
592                         SetForScope<bool> set(record_target, false);
593                         binary.right->visit(*this);
594                 }
595                 type = 0;
596                 binary.left->visit(*this);
597         }
598         else
599         {
600                 TraversingVisitor::visit(binary);
601                 type = 0;
602         }
603 }
604
605 void ProgramCompiler::VariableResolver::visit(Assignment &assign)
606 {
607         {
608                 SetFlag set(record_target);
609                 assignment_target = 0;
610                 assign.left->visit(*this);
611         }
612
613         self_referencing = false;
614         assign.right->visit(*this);
615
616         assign.self_referencing = (self_referencing || assign.oper!="=");
617         assign.target_declaration = assignment_target;
618 }
619
620 void ProgramCompiler::VariableResolver::visit(StructDeclaration &strct)
621 {
622         TraversingVisitor::visit(strct);
623         blocks.back()->types[strct.name] = &strct;
624 }
625
626 void ProgramCompiler::VariableResolver::visit(VariableDeclaration &var)
627 {
628         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
629         {
630                 --i;
631                 map<string, StructDeclaration *>::iterator j = (*i)->types.find(var.type);
632                 if(j!=(*i)->types.end())
633                         var.type_declaration = j->second;
634         }
635
636         if(!block_interface.empty() && var.interface.empty())
637                 var.interface = block_interface;
638
639         TraversingVisitor::visit(var);
640         blocks.back()->variables[var.name] = &var;
641         if(anonymous && blocks.size()>1)
642                 blocks[blocks.size()-2]->variables[var.name] = &var;
643 }
644
645 void ProgramCompiler::VariableResolver::visit(InterfaceBlock &iface)
646 {
647         SetFlag set(anonymous);
648         SetForScope<string> set2(block_interface, iface.interface);
649         TraversingVisitor::visit(iface);
650 }
651
652
653 void ProgramCompiler::FunctionResolver::visit(FunctionCall &call)
654 {
655         map<string, vector<FunctionDeclaration *> >::iterator i = functions.find(call.name);
656         if(i!=functions.end())
657                 call.declaration = i->second.back();
658
659         TraversingVisitor::visit(call);
660 }
661
662 void ProgramCompiler::FunctionResolver::visit(FunctionDeclaration &func)
663 {
664         vector<FunctionDeclaration *> &decls = functions[func.name];
665         if(func.definition)
666         {
667                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
668                         (*i)->definition = func.definition;
669                 decls.clear();
670                 decls.push_back(&func);
671         }
672         else if(!decls.empty() && decls.back()->definition)
673                 func.definition = decls.back()->definition;
674         else
675                 decls.push_back(&func);
676
677         TraversingVisitor::visit(func);
678 }
679
680
681 ProgramCompiler::BlockModifier::BlockModifier():
682         remove_node(false)
683 { }
684
685 void ProgramCompiler::BlockModifier::flatten_block(Block &block)
686 {
687         insert_nodes.insert(insert_nodes.end(), block.body.begin(), block.body.end());
688         remove_node = true;
689 }
690
691 void ProgramCompiler::BlockModifier::apply_and_increment(Block &block, list<RefPtr<Node> >::iterator &i)
692 {
693         block.body.insert(i, insert_nodes.begin(), insert_nodes.end());
694         insert_nodes.clear();
695
696         if(remove_node)
697                 block.body.erase(i++);
698         else
699                 ++i;
700         remove_node = false;
701 }
702
703 void ProgramCompiler::BlockModifier::visit(Block &block)
704 {
705         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
706         {
707                 (*i)->visit(*this);
708                 apply_and_increment(block, i);
709         }
710 }
711
712
713 ProgramCompiler::InterfaceGenerator::InterfaceGenerator():
714         scope_level(0)
715 { }
716
717 string ProgramCompiler::InterfaceGenerator::get_out_prefix(StageType type)
718 {
719         if(type==VERTEX)
720                 return "_vs_out_";
721         else if(type==GEOMETRY)
722                 return "_gs_out_";
723         else
724                 return string();
725 }
726
727 void ProgramCompiler::InterfaceGenerator::apply(Stage &s)
728 {
729         SetForScope<Stage *> set(stage, &s);
730         if(stage->previous)
731                 in_prefix = get_out_prefix(stage->previous->type);
732         out_prefix = get_out_prefix(stage->type);
733         stage->content.visit(*this);
734 }
735
736 void ProgramCompiler::InterfaceGenerator::visit(Block &block)
737 {
738         SetForScope<unsigned> set(scope_level, scope_level+1);
739         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
740         {
741                 (*i)->visit(*this);
742
743                 if(scope_level==1)
744                 {
745                         for(map<string, RefPtr<VariableDeclaration> >::iterator j=iface_declarations.begin(); j!=iface_declarations.end(); ++j)
746                         {
747                                 list<RefPtr<Node> >::iterator k = block.body.insert(i, j->second);
748                                 (*k)->visit(*this);
749                         }
750                         iface_declarations.clear();
751                 }
752
753                 apply_and_increment(block, i);
754         }
755 }
756
757 string ProgramCompiler::InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
758 {
759         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
760         return prefix+name.substr(offset);
761 }
762
763 bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
764 {
765         const map<string, VariableDeclaration *> &stage_vars = (iface=="in" ? stage->in_variables : stage->out_variables);
766         if(stage_vars.count(name) || iface_declarations.count(name))
767                 return false;
768
769         VariableDeclaration* iface_var = new VariableDeclaration;
770         iface_var->sampling = var.sampling;
771         iface_var->interface = iface;
772         iface_var->type = var.type;
773         iface_var->type_declaration = var.type_declaration;
774         iface_var->name = name;
775         if(stage->type==GEOMETRY)
776                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
777         else
778                 iface_var->array = var.array;
779         if(iface_var->array)
780                 iface_var->array_size = var.array_size;
781         if(iface=="in")
782                 iface_var->linked_declaration = &var;
783         iface_declarations[name] = iface_var;
784
785         return true;
786 }
787
788 void ProgramCompiler::InterfaceGenerator::insert_assignment(const string &left, ProgramSyntax::Expression *right)
789 {
790         Assignment *assign = new Assignment;
791         VariableReference *ref = new VariableReference;
792         ref->name = left;
793         assign->left = ref;
794         assign->oper = "=";
795         assign->right = right;
796
797         ExpressionStatement *stmt = new ExpressionStatement;
798         stmt->expression = assign;
799         insert_nodes.push_back(stmt);
800 }
801
802 void ProgramCompiler::InterfaceGenerator::visit(VariableReference &var)
803 {
804         if(var.declaration || !stage->previous)
805                 return;
806         if(iface_declarations.count(var.name))
807                 return;
808
809         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
810         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
811         if(i==prev_out.end())
812                 i = prev_out.find(in_prefix+var.name);
813         if(i!=prev_out.end())
814                 generate_interface(*i->second, "in", var.name);
815 }
816
817 void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &var)
818 {
819         if(var.interface=="out")
820         {
821                 if(scope_level==1)
822                         stage->out_variables[var.name] = &var;
823                 else if(generate_interface(var, "out", change_prefix(var.name, string())))
824                 {
825                         remove_node = true;
826                         if(var.init_expression)
827                                 insert_assignment(var.name, var.init_expression->clone());
828                 }
829         }
830         else if(var.interface=="in")
831         {
832                 stage->in_variables[var.name] = &var;
833                 if(var.linked_declaration)
834                         var.linked_declaration->linked_declaration = &var;
835                 else if(stage->previous)
836                 {
837                         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
838                         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
839                         if(i!=prev_out.end())
840                         {
841                                 var.linked_declaration = i->second;
842                                 i->second->linked_declaration = &var;
843                         }
844                 }
845         }
846
847         TraversingVisitor::visit(var);
848 }
849
850 void ProgramCompiler::InterfaceGenerator::visit(Passthrough &pass)
851 {
852         vector<VariableDeclaration *> pass_vars;
853
854         for(map<string, VariableDeclaration *>::const_iterator i=stage->in_variables.begin(); i!=stage->in_variables.end(); ++i)
855                 pass_vars.push_back(i->second);
856         for(map<string, RefPtr<VariableDeclaration> >::const_iterator i=iface_declarations.begin(); i!=iface_declarations.end(); ++i)
857                 if(i->second->interface=="in")
858                         pass_vars.push_back(i->second.get());
859
860         if(stage->previous)
861         {
862                 const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
863                 for(map<string, VariableDeclaration *>::const_iterator i=prev_out.begin(); i!=prev_out.end(); ++i)
864                 {
865                         bool linked = false;
866                         for(vector<VariableDeclaration *>::const_iterator j=pass_vars.begin(); (!linked && j!=pass_vars.end()); ++j)
867                                 linked = ((*j)->linked_declaration==i->second);
868
869                         if(!linked && generate_interface(*i->second, "in", i->second->name))
870                                 pass_vars.push_back(i->second);
871                 }
872         }
873
874         if(stage->type==GEOMETRY)
875         {
876                 VariableReference *ref = new VariableReference;
877                 ref->name = "gl_in";
878
879                 BinaryExpression *subscript = new BinaryExpression;
880                 subscript->left = ref;
881                 subscript->oper = "[";
882                 subscript->right = pass.subscript;
883                 subscript->after = "]";
884
885                 MemberAccess *memacc = new MemberAccess;
886                 memacc->left = subscript;
887                 memacc->member = "gl_Position";
888
889                 insert_assignment("gl_Position", memacc);
890         }
891
892         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
893         {
894                 string out_name = change_prefix((*i)->name, out_prefix);
895                 generate_interface(**i, "out", out_name);
896
897                 VariableReference *ref = new VariableReference;
898                 ref->name = (*i)->name;
899                 if(pass.subscript)
900                 {
901                         BinaryExpression *subscript = new BinaryExpression;
902                         subscript->left = ref;
903                         subscript->oper = "[";
904                         subscript->right = pass.subscript;
905                         subscript->after = "]";
906                         insert_assignment(out_name, subscript);
907                 }
908                 else
909                         insert_assignment(out_name, ref);
910         }
911
912         remove_node = true;
913 }
914
915
916 void ProgramCompiler::VariableRenamer::visit(VariableReference &var)
917 {
918         if(var.declaration)
919                 var.name = var.declaration->name;
920 }
921
922 void ProgramCompiler::VariableRenamer::visit(VariableDeclaration &var)
923 {
924         if(var.linked_declaration)
925                 var.name = var.linked_declaration->name;
926         TraversingVisitor::visit(var);
927 }
928
929
930 ProgramCompiler::DeclarationReorderer::DeclarationReorderer():
931         kind(NO_DECLARATION)
932 { }
933
934 void ProgramCompiler::DeclarationReorderer::visit(Block &block)
935 {
936         list<RefPtr<Node> >::iterator struct_insert_point = block.body.end();
937         list<RefPtr<Node> >::iterator variable_insert_point = block.body.end();
938
939         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
940         {
941                 kind = NO_DECLARATION;
942                 (*i)->visit(*this);
943
944                 bool moved = false;
945                 if(kind==STRUCT && struct_insert_point!=block.body.end())
946                 {
947                         block.body.insert(struct_insert_point, *i);
948                         moved = true;
949                 }
950                 else if(kind>STRUCT && struct_insert_point==block.body.end())
951                         struct_insert_point = i;
952
953                 if(kind==VARIABLE && variable_insert_point!=block.body.end())
954                 {
955                         block.body.insert(variable_insert_point, *i);
956                         moved = true;
957                 }
958                 else if(kind>VARIABLE && variable_insert_point==block.body.end())
959                         variable_insert_point = i;
960
961                 if(moved)
962                         block.body.erase(i++);
963                 else
964                         ++i;
965         }
966 }
967
968
969 ProgramCompiler::InlineableFunctionLocator::InlineableFunctionLocator():
970         in_function(0)
971 { }
972
973 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionCall &call)
974 {
975         FunctionDeclaration *def = call.declaration;
976         if(def && def->definition!=def)
977                 def = def->definition;
978
979         if(def)
980         {
981                 unsigned &count = refcounts[def];
982                 ++count;
983                 if(count>1 || def==in_function)
984                         inlineable.erase(def);
985         }
986
987         TraversingVisitor::visit(call);
988 }
989
990 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionDeclaration &func)
991 {
992         unsigned &count = refcounts[func.definition];
993         if(!count && func.parameters.empty())
994                 inlineable.insert(func.definition);
995
996         SetForScope<FunctionDeclaration *> set(in_function, &func);
997         TraversingVisitor::visit(func);
998 }
999
1000
1001 ProgramCompiler::FunctionInliner::FunctionInliner():
1002         extract_result(0)
1003 { }
1004
1005 ProgramCompiler::FunctionInliner::FunctionInliner(const set<FunctionDeclaration *> &in):
1006         inlineable(in),
1007         extract_result(0)
1008 { }
1009
1010 void ProgramCompiler::FunctionInliner::visit_and_inline(RefPtr<Expression> &ptr)
1011 {
1012         inline_result = 0;
1013         ptr->visit(*this);
1014         if(inline_result)
1015                 ptr = inline_result;
1016 }
1017
1018 void ProgramCompiler::FunctionInliner::visit(Block &block)
1019 {
1020         if(extract_result)
1021                 --extract_result;
1022
1023         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
1024         {
1025                 (*i)->visit(*this);
1026                 if(extract_result)
1027                         --extract_result;
1028         }
1029 }
1030
1031 void ProgramCompiler::FunctionInliner::visit(UnaryExpression &unary)
1032 {
1033         visit_and_inline(unary.expression);
1034         inline_result = 0;
1035 }
1036
1037 void ProgramCompiler::FunctionInliner::visit(BinaryExpression &binary)
1038 {
1039         visit_and_inline(binary.left);
1040         visit_and_inline(binary.right);
1041         inline_result = 0;
1042 }
1043
1044 void ProgramCompiler::FunctionInliner::visit(FunctionCall &call)
1045 {
1046         for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
1047                 visit_and_inline(*i);
1048
1049         FunctionDeclaration *def = call.declaration;
1050         if(def && def->definition!=def)
1051                 def = def->definition;
1052
1053         if(def && inlineable.count(def))
1054         {
1055                 extract_result = 2;
1056                 def->visit(*this);
1057         }
1058         else
1059                 inline_result = 0;
1060 }
1061
1062 void ProgramCompiler::FunctionInliner::visit(Return &ret)
1063 {
1064         TraversingVisitor::visit(ret);
1065
1066         if(extract_result)
1067                 inline_result = ret.expression->clone();
1068 }
1069
1070
1071 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator():
1072         variable_values(0),
1073         result(0.0f),
1074         result_valid(false)
1075 { }
1076
1077 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator(const ValueMap &v):
1078         variable_values(&v),
1079         result(0.0f),
1080         result_valid(false)
1081 { }
1082
1083 void ProgramCompiler::ExpressionEvaluator::visit(Literal &literal)
1084 {
1085         if(literal.token=="true")
1086                 result = 1.0f;
1087         else if(literal.token=="false")
1088                 result = 0.0f;
1089         else
1090                 result = lexical_cast<float>(literal.token);
1091         result_valid = true;
1092 }
1093
1094 void ProgramCompiler::ExpressionEvaluator::visit(ParenthesizedExpression &parexp)
1095 {
1096         parexp.expression->visit(*this);
1097 }
1098
1099 void ProgramCompiler::ExpressionEvaluator::visit(VariableReference &var)
1100 {
1101         if(!var.declaration)
1102                 return;
1103
1104         if(variable_values)
1105         {
1106                 ValueMap::const_iterator i = variable_values->find(var.declaration);
1107                 if(i!=variable_values->end())
1108                         i->second->visit(*this);
1109         }
1110         else if(var.declaration->init_expression)
1111                 var.declaration->init_expression->visit(*this);
1112 }
1113
1114 void ProgramCompiler::ExpressionEvaluator::visit(UnaryExpression &unary)
1115 {
1116         result_valid = false;
1117         unary.expression->visit(*this);
1118         if(!result_valid)
1119                 return;
1120
1121         if(unary.oper=="!")
1122                 result = !result;
1123         else
1124                 result_valid = false;
1125 }
1126
1127 void ProgramCompiler::ExpressionEvaluator::visit(BinaryExpression &binary)
1128 {
1129         result_valid = false;
1130         binary.left->visit(*this);
1131         if(!result_valid)
1132                 return;
1133
1134         float left_result = result;
1135         result_valid = false;
1136         binary.right->visit(*this);
1137         if(!result_valid)
1138                 return;
1139
1140         if(binary.oper=="<")
1141                 result = (left_result<result);
1142         else if(binary.oper=="<=")
1143                 result = (left_result<=result);
1144         else if(binary.oper==">")
1145                 result = (left_result>result);
1146         else if(binary.oper==">=")
1147                 result = (left_result>=result);
1148         else if(binary.oper=="==")
1149                 result = (left_result==result);
1150         else if(binary.oper=="!=")
1151                 result = (left_result!=result);
1152         else if(binary.oper=="&&")
1153                 result = (left_result && result);
1154         else if(binary.oper=="||")
1155                 result = (left_result || result);
1156         else
1157                 result_valid = false;
1158 }
1159
1160
1161 ProgramCompiler::ConstantConditionEliminator::ConstantConditionEliminator():
1162         scope_level(0)
1163 { }
1164
1165 void ProgramCompiler::ConstantConditionEliminator::visit(Block &block)
1166 {
1167         SetForScope<unsigned> set(scope_level, scope_level+1);
1168         BlockModifier::visit(block);
1169
1170         for(map<string, VariableDeclaration *>::const_iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
1171                 variable_values.erase(i->second);
1172 }
1173
1174 void ProgramCompiler::ConstantConditionEliminator::visit(Assignment &assign)
1175 {
1176         variable_values.erase(assign.target_declaration);
1177 }
1178
1179 void ProgramCompiler::ConstantConditionEliminator::visit(VariableDeclaration &var)
1180 {
1181         if(var.constant || scope_level>1)
1182                 variable_values[&var] = var.init_expression.get();
1183 }
1184
1185 void ProgramCompiler::ConstantConditionEliminator::visit(Conditional &cond)
1186 {
1187         ExpressionEvaluator eval(variable_values);
1188         cond.condition->visit(eval);
1189         if(eval.result_valid)
1190                 flatten_block(eval.result ? cond.body : cond.else_body);
1191         else
1192                 TraversingVisitor::visit(cond);
1193 }
1194
1195 void ProgramCompiler::ConstantConditionEliminator::visit(Iteration &iter)
1196 {
1197         if(iter.condition)
1198         {
1199                 ExpressionEvaluator eval;
1200                 iter.condition->visit(eval);
1201                 if(eval.result_valid && !eval.result)
1202                 {
1203                         remove_node = true;
1204                         return;
1205                 }
1206         }
1207
1208         TraversingVisitor::visit(iter);
1209 }
1210
1211
1212 ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
1213         aggregate(0),
1214         assignment(0),
1215         assignment_target(false),
1216         global_scope(true)
1217 { }
1218
1219 void ProgramCompiler::UnusedVariableLocator::apply(Stage &s)
1220 {
1221         variables.push_back(BlockVariableMap());
1222         Visitor::apply(s);
1223         BlockVariableMap &global_variables = variables.back();
1224         for(BlockVariableMap::iterator i=global_variables.begin(); i!=global_variables.end(); ++i)
1225         {
1226                 if(i->first->interface=="out" && (s.type==FRAGMENT || i->first->linked_declaration || !i->first->name.compare(0, 3, "gl_")))
1227                         continue;
1228                 if(!i->second.referenced)
1229                 {
1230                         unused_nodes.insert(i->first);
1231                         for(vector<Node *>::iterator j=i->second.assignments.begin(); j!=i->second.assignments.end(); ++j)
1232                                 unused_nodes.insert(*j);
1233                 }
1234         }
1235         variables.pop_back();
1236 }
1237
1238 void ProgramCompiler::UnusedVariableLocator::visit(VariableReference &var)
1239 {
1240         map<VariableDeclaration *, Node *>::iterator i = aggregates.find(var.declaration);
1241         if(i!=aggregates.end())
1242                 unused_nodes.erase(i->second);
1243
1244         if(var.declaration && !assignment_target)
1245         {
1246                 VariableInfo &var_info = variables.back()[var.declaration];
1247                 var_info.assignments.clear();
1248                 var_info.referenced = true;
1249         }
1250 }
1251
1252 void ProgramCompiler::UnusedVariableLocator::visit(MemberAccess &memacc)
1253 {
1254         TraversingVisitor::visit(memacc);
1255         unused_nodes.erase(memacc.declaration);
1256 }
1257
1258 void ProgramCompiler::UnusedVariableLocator::visit(BinaryExpression &binary)
1259 {
1260         if(binary.oper=="[")
1261         {
1262                 binary.left->visit(*this);
1263                 SetForScope<bool> set(assignment_target, false);
1264                 binary.right->visit(*this);
1265         }
1266         else
1267                 TraversingVisitor::visit(binary);
1268 }
1269
1270 void ProgramCompiler::UnusedVariableLocator::visit(Assignment &assign)
1271 {
1272         {
1273                 SetForScope<bool> set(assignment_target, !assign.self_referencing);
1274                 assign.left->visit(*this);
1275         }
1276         assign.right->visit(*this);
1277         assignment = &assign;
1278 }
1279
1280 void ProgramCompiler::UnusedVariableLocator::record_assignment(VariableDeclaration &var, Node &node, bool self_ref)
1281 {
1282         VariableInfo &var_info = variables.back()[&var];
1283         if(!self_ref)
1284                 var_info.assignments.clear();
1285         var_info.assignments.push_back(&node);
1286         var_info.conditionally_assigned = false;
1287 }
1288
1289 void ProgramCompiler::UnusedVariableLocator::visit(ExpressionStatement &expr)
1290 {
1291         assignment = 0;
1292         TraversingVisitor::visit(expr);
1293         if(assignment && assignment->target_declaration)
1294                 record_assignment(*assignment->target_declaration, expr, assignment->self_referencing);
1295 }
1296
1297 void ProgramCompiler::UnusedVariableLocator::visit(StructDeclaration &strct)
1298 {
1299         SetForScope<Node *> set(aggregate, &strct);
1300         unused_nodes.insert(&strct);
1301         TraversingVisitor::visit(strct);
1302 }
1303
1304 void ProgramCompiler::UnusedVariableLocator::visit(VariableDeclaration &var)
1305 {
1306         if(aggregate)
1307                 aggregates[&var] = aggregate;
1308         else
1309         {
1310                 variables.back()[&var].local = true;
1311                 if(var.init_expression)
1312                         record_assignment(var, *var.init_expression, false);
1313         }
1314         unused_nodes.erase(var.type_declaration);
1315         TraversingVisitor::visit(var);
1316 }
1317
1318 void ProgramCompiler::UnusedVariableLocator::visit(InterfaceBlock &iface)
1319 {
1320         SetForScope<Node *> set(aggregate, &iface);
1321         unused_nodes.insert(&iface);
1322         TraversingVisitor::visit(iface);
1323 }
1324
1325 void ProgramCompiler::UnusedVariableLocator::visit(FunctionDeclaration &func)
1326 {
1327         variables.push_back(BlockVariableMap());
1328
1329         {
1330                 SetForScope<bool> set(global_scope, false);
1331                 for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1332                         (*i)->visit(*this);
1333                 func.body.visit(*this);
1334         }
1335
1336         BlockVariableMap &block_variables = variables.back();
1337         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1338                 i->second.conditionally_assigned = true;
1339         merge_down_variables();
1340 }
1341
1342 void ProgramCompiler::UnusedVariableLocator::merge_down_variables()
1343 {
1344         BlockVariableMap &parent_variables = variables[variables.size()-2];
1345         BlockVariableMap &block_variables = variables.back();
1346         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1347         {
1348                 if(i->second.local)
1349                 {
1350                         if(!i->second.referenced)
1351                                 unused_nodes.insert(i->first);
1352                         for(vector<Node *>::iterator j=i->second.assignments.begin(); j!=i->second.assignments.end(); ++j)
1353                                 unused_nodes.insert(*j);
1354                         continue;
1355                 }
1356
1357                 BlockVariableMap::iterator j = parent_variables.find(i->first);
1358                 if(j==parent_variables.end())
1359                         parent_variables.insert(*i);
1360                 else
1361                 {
1362                         if(!i->second.conditionally_assigned)
1363                         {
1364                                 j->second.assignments.clear();
1365                                 j->second.conditionally_assigned = true;
1366                         }
1367                         j->second.referenced |= i->second.referenced;
1368                         j->second.assignments.insert(j->second.assignments.end(), i->second.assignments.begin(), i->second.assignments.end());
1369                 }
1370         }
1371         variables.pop_back();
1372 }
1373
1374 void ProgramCompiler::UnusedVariableLocator::visit(Conditional &cond)
1375 {
1376         cond.condition->visit(*this);
1377         variables.push_back(BlockVariableMap());
1378         cond.body.visit(*this);
1379
1380         BlockVariableMap if_variables;
1381         swap(variables.back(), if_variables);
1382         cond.else_body.visit(*this);
1383
1384         BlockVariableMap &else_variables = variables.back();
1385         for(BlockVariableMap::iterator i=else_variables.begin(); i!=else_variables.end(); ++i)
1386         {
1387                 BlockVariableMap::iterator j = if_variables.find(i->first);
1388                 if(j!=if_variables.end())
1389                 {
1390                         i->second.assignments.insert(i->second.assignments.end(), j->second.assignments.begin(), j->second.assignments.end());
1391                         i->second.conditionally_assigned |= j->second.conditionally_assigned;
1392                         if_variables.erase(j);
1393                 }
1394                 else
1395                         i->second.conditionally_assigned = true;
1396         }
1397
1398         for(BlockVariableMap::iterator i=if_variables.begin(); i!=if_variables.end(); ++i)
1399         {
1400                 i->second.conditionally_assigned = true;
1401                 else_variables.insert(*i);
1402         }
1403
1404         merge_down_variables();
1405 }
1406
1407 void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
1408 {
1409         variables.push_back(BlockVariableMap());
1410         TraversingVisitor::visit(iter);
1411
1412         BlockVariableMap &block_variables = variables.back();
1413         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1414                 if(!i->second.local && i->second.referenced)
1415                         i->second.assignments.clear();
1416
1417         merge_down_variables();
1418 }
1419
1420
1421 ProgramCompiler::UnusedVariableLocator::VariableInfo::VariableInfo():
1422         local(false),
1423         conditionally_assigned(false),
1424         referenced(false)
1425 { }
1426
1427
1428 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionCall &call)
1429 {
1430         TraversingVisitor::visit(call);
1431
1432         unused_nodes.erase(call.declaration);
1433         if(call.declaration && call.declaration->definition!=call.declaration)
1434                 used_definitions.insert(call.declaration->definition);
1435 }
1436
1437 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionDeclaration &func)
1438 {
1439         TraversingVisitor::visit(func);
1440
1441         if(func.name!="main" && !used_definitions.count(&func))
1442                 unused_nodes.insert(&func);
1443 }
1444
1445
1446 ProgramCompiler::NodeRemover::NodeRemover(const set<Node *> &r):
1447         to_remove(r)
1448 { }
1449
1450 void ProgramCompiler::NodeRemover::visit(Block &block)
1451 {
1452         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
1453         {
1454                 (*i)->visit(*this);
1455                 if(to_remove.count(i->get()))
1456                         block.body.erase(i++);
1457                 else
1458                         ++i;
1459         }
1460 }
1461
1462 void ProgramCompiler::NodeRemover::visit(VariableDeclaration &var)
1463 {
1464         if(to_remove.count(&var))
1465         {
1466                 stage->in_variables.erase(var.name);
1467                 stage->out_variables.erase(var.name);
1468                 stage->locations.erase(var.name);
1469                 if(var.linked_declaration)
1470                         var.linked_declaration->linked_declaration = 0;
1471         }
1472         else if(var.init_expression && to_remove.count(var.init_expression.get()))
1473                 var.init_expression = 0;
1474 }
1475
1476
1477 ProgramCompiler::LegacyConverter::LegacyConverter():
1478         target_version(get_glsl_version())
1479 { }
1480
1481 ProgramCompiler::LegacyConverter::LegacyConverter(const Version &v):
1482         target_version(v)
1483 { }
1484
1485 bool ProgramCompiler::LegacyConverter::check_version(const Version &feature_version)
1486 {
1487         if(target_version<feature_version)
1488                 return false;
1489         else if(stage->required_version<feature_version)
1490                 stage->required_version = feature_version;
1491
1492         return true;
1493 }
1494
1495 void ProgramCompiler::LegacyConverter::visit(VariableReference &var)
1496 {
1497         if(var.name==frag_out_name && !check_version(Version(1, 30)))
1498         {
1499                 var.name = "gl_FragColor";
1500                 var.declaration = 0;
1501                 type = "vec4";
1502         }
1503         else if(var.declaration)
1504                 type = var.declaration->type;
1505         else
1506                 type = string();
1507 }
1508
1509 void ProgramCompiler::LegacyConverter::visit(FunctionCall &call)
1510 {
1511         if(call.name=="texture" && !call.declaration && !check_version(Version(1, 30)))
1512         {
1513                 vector<RefPtr<Expression> >::iterator i = call.arguments.begin();
1514                 if(i!=call.arguments.end())
1515                 {
1516                         (*i)->visit(*this);
1517                         if(type=="sampler1D")
1518                                 call.name = "texture1D";
1519                         else if(type=="sampler2D")
1520                                 call.name = "texture2D";
1521                         else if(type=="sampler3D")
1522                                 call.name = "texture3D";
1523                         else if(type=="sampler1DShadow")
1524                                 call.name = "shadow1D";
1525                         else if(type=="sampler2DShadow")
1526                                 call.name = "shadow2D";
1527
1528                         for(; i!=call.arguments.end(); ++i)
1529                                 (*i)->visit(*this);
1530                 }
1531         }
1532         else
1533                 TraversingVisitor::visit(call);
1534 }
1535
1536 void ProgramCompiler::LegacyConverter::visit(VariableDeclaration &var)
1537 {
1538         if(var.layout && !check_version(Version(3, 30)))
1539         {
1540                 vector<Layout::Qualifier>::iterator i;
1541                 for(i=var.layout->qualifiers.begin(); (i!=var.layout->qualifiers.end() && i->identifier!="location"); ++i) ;
1542                 if(i!=var.layout->qualifiers.end())
1543                 {
1544                         unsigned location = lexical_cast<unsigned>(i->value);
1545                         if(stage->type==VERTEX && var.interface=="in")
1546                         {
1547                                 stage->locations[var.name] = location;
1548                                 var.layout->qualifiers.erase(i);
1549                         }
1550                         else if(stage->type==FRAGMENT && var.interface=="out")
1551                         {
1552                                 stage->locations[var.name] = location;
1553                                 var.layout->qualifiers.erase(i);
1554                         }
1555
1556                         if(var.layout->qualifiers.empty())
1557                                 var.layout = 0;
1558                 }
1559         }
1560
1561         if((var.interface=="in" || var.interface=="out") && !check_version(Version(1, 30)))
1562         {
1563                 if(stage->type==VERTEX && var.interface=="in")
1564                         var.interface = "attribute";
1565                 else if((stage->type==VERTEX && var.interface=="out") || (stage->type==FRAGMENT && var.interface=="in"))
1566                         var.interface = "varying";
1567                 else if(stage->type==FRAGMENT && var.interface=="out")
1568                 {
1569                         frag_out_name = var.name;
1570                         remove_node = true;
1571                 }
1572         }
1573
1574         TraversingVisitor::visit(var);
1575 }
1576
1577 void ProgramCompiler::LegacyConverter::visit(InterfaceBlock &iface)
1578 {
1579         if(!check_version(Version(1, 50)))
1580                 flatten_block(iface.members);
1581 }
1582
1583 } // namespace GL
1584 } // namespace Msp