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Support while loops in GLSL
[libs/gl.git] / source / programcompiler.cpp
1 #include <msp/core/raii.h>
2 #include <msp/gl/extensions/ext_gpu_shader4.h>
3 #include <msp/strings/format.h>
4 #include <msp/strings/utils.h>
5 #include "error.h"
6 #include "program.h"
7 #include "programcompiler.h"
8 #include "resources.h"
9 #include "shader.h"
10
11 using namespace std;
12
13 namespace {
14
15 const char builtins_src[] =
16         "#pragma MSP stage(vertex)\n"
17         "out gl_PerVertex {\n"
18         "  vec4 gl_Position;\n"
19         "  float gl_ClipDistance[];\n"
20         "};\n"
21         "#pragma MSP stage(geometry)\n"
22         "in gl_PerVertex {\n"
23         "  vec4 gl_Position;\n"
24         "  float gl_ClipDistance[];\n"
25         "} gl_in[];\n"
26         "out gl_PerVertex {\n"
27         "  vec4 gl_Position;\n"
28         "  float gl_ClipDistance[];\n"
29         "};\n";
30
31 }
32
33 namespace Msp {
34 namespace GL {
35
36 using namespace ProgramSyntax;
37
38 ProgramCompiler::ProgramCompiler():
39         resources(0),
40         module(0)
41 { }
42
43 ProgramCompiler::~ProgramCompiler()
44 {
45         delete module;
46 }
47
48 void ProgramCompiler::compile(const string &source, const string &src_name)
49 {
50         resources = 0;
51         delete module;
52         module = new Module();
53         ProgramParser parser;
54         imported_names.insert(src_name);
55         append_module(parser.parse(source, src_name));
56         process();
57 }
58
59 void ProgramCompiler::compile(IO::Base &io, Resources *res, const string &src_name)
60 {
61         resources = res;
62         delete module;
63         module = new Module();
64         ProgramParser parser;
65         imported_names.insert(src_name);
66         append_module(parser.parse(io, src_name));
67         process();
68 }
69
70 void ProgramCompiler::compile(IO::Base &io, const string &src_name)
71 {
72         compile(io, 0, src_name);
73 }
74
75 void ProgramCompiler::add_shaders(Program &program)
76 {
77         if(!module)
78                 throw invalid_operation("ProgramCompiler::add_shaders");
79
80         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
81         {
82                 if(i->type==VERTEX)
83                 {
84                         program.attach_shader_owned(new VertexShader(apply<Formatter>(*i)));
85                         for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
86                                 program.bind_attribute(j->second, j->first);
87                 }
88                 else if(i->type==GEOMETRY)
89                         program.attach_shader_owned(new GeometryShader(apply<Formatter>(*i)));
90                 else if(i->type==FRAGMENT)
91                 {
92                         program.attach_shader_owned(new FragmentShader(apply<Formatter>(*i)));
93                         if(EXT_gpu_shader4)
94                         {
95                                 for(map<string, unsigned>::iterator j=i->locations.begin(); j!=i->locations.end(); ++j)
96                                         program.bind_fragment_data(j->second, j->first);
97                         }
98                 }
99         }
100 }
101
102 Module *ProgramCompiler::create_builtins_module()
103 {
104         ProgramParser parser;
105         Module *module = new Module(parser.parse(builtins_src, "<builtin>"));
106         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
107         {
108                 VariableResolver resolver;
109                 i->content.visit(resolver);
110                 for(map<string, VariableDeclaration *>::iterator j=i->content.variables.begin(); j!=i->content.variables.end(); ++j)
111                         j->second->linked_declaration = j->second;
112         }
113         return module;
114 }
115
116 Module &ProgramCompiler::get_builtins_module()
117 {
118         static RefPtr<Module> builtins_module = create_builtins_module();
119         return *builtins_module;
120 }
121
122 Stage *ProgramCompiler::get_builtins(StageType type)
123 {
124         Module &module = get_builtins_module();
125         for(list<Stage>::iterator i=module.stages.begin(); i!=module.stages.end(); ++i)
126                 if(i->type==type)
127                         return &*i;
128         return 0;
129 }
130
131 void ProgramCompiler::append_module(ProgramSyntax::Module &mod)
132 {
133         vector<Import *> imports = apply<NodeGatherer<Import> >(mod.shared);
134         for(vector<Import *>::iterator i=imports.begin(); i!=imports.end(); ++i)
135                 import((*i)->module);
136         apply<NodeRemover>(mod.shared, set<Node *>(imports.begin(), imports.end()));
137
138         append_stage(mod.shared);
139         for(list<Stage>::iterator i=mod.stages.begin(); i!=mod.stages.end(); ++i)
140                 append_stage(*i);
141 }
142
143 void ProgramCompiler::append_stage(Stage &stage)
144 {
145         Stage *target = 0;
146         if(stage.type==SHARED)
147                 target = &module->shared;
148         else
149         {
150                 list<Stage>::iterator i;
151                 for(i=module->stages.begin(); (i!=module->stages.end() && i->type<stage.type); ++i) ;
152                 if(i==module->stages.end() || i->type>stage.type)
153                 {
154                         list<Stage>::iterator j = module->stages.insert(i, stage.type);
155                         if(i!=module->stages.end())
156                                 i->previous = &*j;
157                         i = j;
158                         if(i!=module->stages.begin())
159                                 i->previous = &*--j;
160                 }
161
162                 target = &*i;
163         }
164
165         for(NodeList<Node>::iterator i=stage.content.body.begin(); i!=stage.content.body.end(); ++i)
166                 target->content.body.push_back(*i);
167         apply<DeclarationCombiner>(*target);
168 }
169
170 void ProgramCompiler::process()
171 {
172         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
173                 generate(*i);
174         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); )
175         {
176                 if(optimize(*i))
177                         i = module->stages.begin();
178                 else
179                         ++i;
180         }
181         for(list<Stage>::iterator i=module->stages.begin(); i!=module->stages.end(); ++i)
182                 finalize(*i);
183 }
184
185 void ProgramCompiler::import(const string &name)
186 {
187         string fn = name+".glsl";
188         if(imported_names.count(fn))
189                 return;
190         imported_names.insert(fn);
191
192         RefPtr<IO::Seekable> io = (resources ? resources->open_raw(fn) : Resources::get_builtins().open(fn));
193         if(!io)
194                 throw runtime_error(format("module %s not found", name));
195         ProgramParser import_parser;
196         append_module(import_parser.parse(*io, fn));
197 }
198
199 void ProgramCompiler::generate(Stage &stage)
200 {
201         inject_block(stage.content, module->shared.content);
202
203         apply<DeclarationReorderer>(stage);
204         apply<FunctionResolver>(stage);
205         apply<VariableResolver>(stage);
206         apply<InterfaceGenerator>(stage);
207         apply<VariableResolver>(stage);
208         apply<DeclarationReorderer>(stage);
209         apply<FunctionResolver>(stage);
210         apply<LegacyConverter>(stage);
211 }
212
213 bool ProgramCompiler::optimize(Stage &stage)
214 {
215         apply<ConstantConditionEliminator>(stage);
216
217         set<FunctionDeclaration *> inlineable = apply<InlineableFunctionLocator>(stage);
218         apply<FunctionInliner>(stage, inlineable);
219
220         set<Node *> unused = apply<UnusedVariableLocator>(stage);
221         set<Node *> unused2 = apply<UnusedFunctionLocator>(stage);
222         unused.insert(unused2.begin(), unused2.end());
223         apply<NodeRemover>(stage, unused);
224
225         return !unused.empty();
226 }
227
228 void ProgramCompiler::finalize(Stage &stage)
229 {
230         if(get_gl_api()==OPENGL_ES2)
231                 apply<DefaultPrecisionGenerator>(stage);
232         else
233                 apply<PrecisionRemover>(stage);
234 }
235
236 void ProgramCompiler::inject_block(Block &target, const Block &source)
237 {
238         list<RefPtr<Node> >::iterator insert_point = target.body.begin();
239         for(list<RefPtr<Node> >::const_iterator i=source.body.begin(); i!=source.body.end(); ++i)
240                 target.body.insert(insert_point, (*i)->clone());
241 }
242
243 template<typename T>
244 typename T::ResultType ProgramCompiler::apply(Stage &stage)
245 {
246         T visitor;
247         visitor.apply(stage);
248         return visitor.get_result();
249 }
250
251 template<typename T, typename A>
252 typename T::ResultType ProgramCompiler::apply(Stage &stage, const A &arg)
253 {
254         T visitor(arg);
255         visitor.apply(stage);
256         return visitor.get_result();
257 }
258
259
260 ProgramCompiler::Visitor::Visitor():
261         stage(0)
262 { }
263
264 void ProgramCompiler::Visitor::apply(Stage &s)
265 {
266         SetForScope<Stage *> set(stage, &s);
267         stage->content.visit(*this);
268 }
269
270
271 ProgramCompiler::BlockModifier::BlockModifier():
272         remove_node(false)
273 { }
274
275 void ProgramCompiler::BlockModifier::flatten_block(Block &block)
276 {
277         insert_nodes.insert(insert_nodes.end(), block.body.begin(), block.body.end());
278         remove_node = true;
279 }
280
281 void ProgramCompiler::BlockModifier::apply_and_increment(Block &block, list<RefPtr<Node> >::iterator &i)
282 {
283         block.body.insert(i, insert_nodes.begin(), insert_nodes.end());
284         insert_nodes.clear();
285
286         if(remove_node)
287                 block.body.erase(i++);
288         else
289                 ++i;
290         remove_node = false;
291 }
292
293 void ProgramCompiler::BlockModifier::visit(Block &block)
294 {
295         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
296         {
297                 (*i)->visit(*this);
298                 apply_and_increment(block, i);
299         }
300 }
301
302
303 ProgramCompiler::Formatter::Formatter():
304         indent(0),
305         parameter_list(false),
306         else_if(0)
307 { }
308
309 void ProgramCompiler::Formatter::apply(ProgramSyntax::Stage &s)
310 {
311         GLApi api = get_gl_api();
312         const Version &ver = s.required_version;
313
314         if(ver)
315         {
316                 formatted += format("#version %d%02d", ver.major, ver.minor);
317                 if(api==OPENGL_ES2 && ver>=Version(3, 0))
318                         formatted += " es";
319                 formatted += '\n';
320         }
321
322         Visitor::apply(s);
323 }
324
325 void ProgramCompiler::Formatter::visit(Literal &literal)
326 {
327         formatted += literal.token;
328 }
329
330 void ProgramCompiler::Formatter::visit(ParenthesizedExpression &parexpr)
331 {
332         formatted += '(';
333         parexpr.expression->visit(*this);
334         formatted += ')';
335 }
336
337 void ProgramCompiler::Formatter::visit(VariableReference &var)
338 {
339         formatted += var.name;
340 }
341
342 void ProgramCompiler::Formatter::visit(MemberAccess &memacc)
343 {
344         memacc.left->visit(*this);
345         formatted += format(".%s", memacc.member);
346 }
347
348 void ProgramCompiler::Formatter::visit(UnaryExpression &unary)
349 {
350         if(unary.prefix)
351                 formatted += unary.oper;
352         unary.expression->visit(*this);
353         if(!unary.prefix)
354                 formatted += unary.oper;
355 }
356
357 void ProgramCompiler::Formatter::visit(BinaryExpression &binary)
358 {
359         binary.left->visit(*this);
360         formatted += binary.oper;
361         binary.right->visit(*this);
362         formatted += binary.after;
363 }
364
365 void ProgramCompiler::Formatter::visit(Assignment &assign)
366 {
367         assign.left->visit(*this);
368         formatted += format(" %s ", assign.oper);
369         assign.right->visit(*this);
370 }
371
372 void ProgramCompiler::Formatter::visit(FunctionCall &call)
373 {
374         formatted += format("%s(", call.name);
375         for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
376         {
377                 if(i!=call.arguments.begin())
378                         formatted += ", ";
379                 (*i)->visit(*this);
380         }
381         formatted += ')';
382 }
383
384 void ProgramCompiler::Formatter::visit(ExpressionStatement &expr)
385 {
386         expr.expression->visit(*this);
387         formatted += ';';
388 }
389
390 void ProgramCompiler::Formatter::visit(Block &block)
391 {
392         if(else_if)
393                 --else_if;
394
395         unsigned brace_indent = indent;
396         bool use_braces = (block.use_braces || (indent && block.body.size()!=1));
397         if(use_braces)
398                 formatted += format("%s{\n", string(brace_indent*2, ' '));
399
400         SetForScope<unsigned> set(indent, indent+(indent>0 || use_braces));
401         string spaces(indent*2, ' ');
402         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
403         {
404                 if(i!=block.body.begin())
405                         formatted += '\n';
406                 formatted += spaces;
407                 (*i)->visit(*this);
408                 else_if = 0;
409         }
410
411         if(use_braces)
412                 formatted += format("\n%s}", string(brace_indent*2, ' '));
413 }
414
415 void ProgramCompiler::Formatter::visit(Import &import)
416 {
417         formatted += format("import %s;", import.module);
418 }
419
420 void ProgramCompiler::Formatter::visit(Precision &prec)
421 {
422         formatted += format("precision %s %s;", prec.precision, prec.type);
423 }
424
425 void ProgramCompiler::Formatter::visit(Layout &layout)
426 {
427         formatted += "layout(";
428         for(vector<Layout::Qualifier>::const_iterator i=layout.qualifiers.begin(); i!=layout.qualifiers.end(); ++i)
429         {
430                 if(i!=layout.qualifiers.begin())
431                         formatted += ", ";
432                 formatted += i->identifier;
433                 if(!i->value.empty())
434                         formatted += format("=%s", i->value);
435         }
436         formatted += ')';
437 }
438
439 void ProgramCompiler::Formatter::visit(InterfaceLayout &layout)
440 {
441         layout.layout.visit(*this);
442         formatted += format(" %s;", layout.interface);
443 }
444
445 void ProgramCompiler::Formatter::visit(StructDeclaration &strct)
446 {
447         formatted += format("struct %s\n", strct.name);
448         strct.members.visit(*this);
449         formatted += ';';
450 }
451
452 void ProgramCompiler::Formatter::visit(VariableDeclaration &var)
453 {
454         if(var.layout)
455         {
456                 var.layout->visit(*this);
457                 formatted += ' ';
458         }
459         if(var.constant)
460                 formatted += "const ";
461         if(!var.interpolation.empty())
462                 formatted += format("%s ", var.interpolation);
463         if(!var.sampling.empty())
464                 formatted += format("%s ", var.sampling);
465         if(!var.interface.empty() && var.interface!=block_interface)
466         {
467                 string interface = var.interface;
468                 if(stage->required_version<Version(1, 30))
469                 {
470                         if(stage->type==VERTEX && var.interface=="in")
471                                 interface = "attribute";
472                         else if((stage->type==VERTEX && var.interface=="out") || (stage->type==FRAGMENT && var.interface=="in"))
473                                 interface = "varying";
474                 }
475                 formatted += format("%s ", interface);
476         }
477         if(!var.precision.empty())
478                 formatted += format("%s ", var.precision);
479         formatted += format("%s %s", var.type, var.name);
480         if(var.array)
481         {
482                 formatted += '[';
483                 if(var.array_size)
484                         var.array_size->visit(*this);
485                 formatted += ']';
486         }
487         if(var.init_expression)
488         {
489                 formatted += " = ";
490                 var.init_expression->visit(*this);
491         }
492         if(!parameter_list)
493                 formatted += ';';
494 }
495
496 void ProgramCompiler::Formatter::visit(InterfaceBlock &iface)
497 {
498         SetForScope<string> set(block_interface, iface.interface);
499         formatted += format("%s %s\n", iface.interface, iface.name);
500         iface.members.visit(*this);
501         formatted += ';';
502 }
503
504 void ProgramCompiler::Formatter::visit(FunctionDeclaration &func)
505 {
506         formatted += format("%s %s(", func.return_type, func.name);
507         for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
508         {
509                 if(i!=func.parameters.begin())
510                         formatted += ", ";
511                 SetFlag set(parameter_list);
512                 (*i)->visit(*this);
513         }
514         formatted += ')';
515         if(func.definition==&func)
516         {
517                 formatted += '\n';
518                 func.body.visit(*this);
519         }
520         else
521                 formatted += ';';
522 }
523
524 void ProgramCompiler::Formatter::visit(Conditional &cond)
525 {
526         if(else_if)
527                 formatted.replace(formatted.rfind('\n'), string::npos, 1, ' ');
528
529         indent -= else_if;
530
531         formatted += "if(";
532         cond.condition->visit(*this);
533         formatted += ")\n";
534
535         cond.body.visit(*this);
536         if(!cond.else_body.body.empty())
537         {
538                 formatted += format("\n%selse\n", string(indent*2, ' '));
539                 SetForScope<unsigned> set(else_if, 2);
540                 cond.else_body.visit(*this);
541         }
542 }
543
544 void ProgramCompiler::Formatter::visit(Iteration &iter)
545 {
546         if(!iter.init_statement && iter.condition && !iter.loop_expression)
547         {
548                 formatted += "while(";
549                 iter.condition->visit(*this);
550                 formatted += ')';
551         }
552         else
553         {
554                 formatted += "for(";
555                 if(iter.init_statement)
556                         iter.init_statement->visit(*this);
557                 else
558                         formatted += ';';
559                 if(iter.condition)
560                 {
561                         formatted += ' ';
562                         iter.condition->visit(*this);
563                 }
564                 formatted += ';';
565                 if(iter.loop_expression)
566                 {
567                         formatted += ' ';
568                         iter.loop_expression->visit(*this);
569                 }
570                 formatted += ')';
571         }
572
573         if(iter.body.body.empty())
574                 formatted += " { }";
575         else
576         {
577                 formatted += '\n';
578                 iter.body.visit(*this);
579         }
580 }
581
582 void ProgramCompiler::Formatter::visit(Return &ret)
583 {
584         formatted += "return";
585         if(ret.expression)
586         {
587                 formatted += ' ';
588                 ret.expression->visit(*this);
589         }
590         formatted += ';';
591 }
592
593 void ProgramCompiler::Formatter::visit(Jump &jump)
594 {
595         formatted += jump.keyword;
596         formatted += ';';
597 }
598
599
600 ProgramCompiler::DeclarationCombiner::DeclarationCombiner():
601         toplevel(true)
602 { }
603
604 void ProgramCompiler::DeclarationCombiner::visit(Block &block)
605 {
606         if(!toplevel)
607                 return;
608
609         SetForScope<bool> set(toplevel, false);
610         BlockModifier::visit(block);
611 }
612
613 void ProgramCompiler::DeclarationCombiner::visit(FunctionDeclaration &func)
614 {
615         vector<FunctionDeclaration *> &decls = functions[func.name];
616         if(func.definition)
617         {
618                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
619                 {
620                         (*i)->definition = func.definition;
621                         (*i)->body.body.clear();
622                 }
623         }
624         decls.push_back(&func);
625 }
626
627 void ProgramCompiler::DeclarationCombiner::visit(VariableDeclaration &var)
628 {
629         VariableDeclaration *&ptr = variables[var.name];
630         if(ptr)
631         {
632                 ptr->type = var.type;
633                 if(var.init_expression)
634                         ptr->init_expression = var.init_expression;
635                 remove_node = true;
636         }
637         else
638                 ptr = &var;
639 }
640
641
642 ProgramCompiler::VariableResolver::VariableResolver():
643         anonymous(false),
644         record_target(false),
645         assignment_target(0),
646         self_referencing(false)
647 { }
648
649 void ProgramCompiler::VariableResolver::apply(Stage &s)
650 {
651         SetForScope<Stage *> set(stage, &s);
652         Stage *builtins = get_builtins(stage->type);
653         if(builtins)
654                 blocks.push_back(&builtins->content);
655         stage->content.visit(*this);
656         if(builtins)
657                 blocks.pop_back();
658 }
659
660 void ProgramCompiler::VariableResolver::visit(Block &block)
661 {
662         blocks.push_back(&block);
663         block.variables.clear();
664         TraversingVisitor::visit(block);
665         blocks.pop_back();
666 }
667
668 void ProgramCompiler::VariableResolver::visit(VariableReference &var)
669 {
670         var.declaration = 0;
671         type = 0;
672         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
673         {
674                 --i;
675                 map<string, VariableDeclaration *>::iterator j = (*i)->variables.find(var.name);
676                 if(j!=(*i)->variables.end())
677                 {
678                         var.declaration = j->second;
679                         type = j->second->type_declaration;
680                         break;
681                 }
682         }
683
684         if(record_target)
685         {
686                 if(assignment_target)
687                 {
688                         record_target = false;
689                         assignment_target = 0;
690                 }
691                 else
692                         assignment_target = var.declaration;
693         }
694         else if(var.declaration && var.declaration==assignment_target)
695                 self_referencing = true;
696 }
697
698 void ProgramCompiler::VariableResolver::visit(MemberAccess &memacc)
699 {
700         type = 0;
701         TraversingVisitor::visit(memacc);
702         memacc.declaration = 0;
703         if(type)
704         {
705                 map<string, VariableDeclaration *>::iterator i = type->members.variables.find(memacc.member);
706                 if(i!=type->members.variables.end())
707                 {
708                         memacc.declaration = i->second;
709                         type = i->second->type_declaration;
710                 }
711                 else
712                         type = 0;
713         }
714 }
715
716 void ProgramCompiler::VariableResolver::visit(BinaryExpression &binary)
717 {
718         if(binary.oper=="[")
719         {
720                 {
721                         SetForScope<bool> set(record_target, false);
722                         binary.right->visit(*this);
723                 }
724                 type = 0;
725                 binary.left->visit(*this);
726         }
727         else
728         {
729                 TraversingVisitor::visit(binary);
730                 type = 0;
731         }
732 }
733
734 void ProgramCompiler::VariableResolver::visit(Assignment &assign)
735 {
736         {
737                 SetFlag set(record_target);
738                 assignment_target = 0;
739                 assign.left->visit(*this);
740         }
741
742         self_referencing = false;
743         assign.right->visit(*this);
744
745         assign.self_referencing = (self_referencing || assign.oper!="=");
746         assign.target_declaration = assignment_target;
747 }
748
749 void ProgramCompiler::VariableResolver::visit(StructDeclaration &strct)
750 {
751         TraversingVisitor::visit(strct);
752         blocks.back()->types[strct.name] = &strct;
753 }
754
755 void ProgramCompiler::VariableResolver::visit(VariableDeclaration &var)
756 {
757         for(vector<Block *>::iterator i=blocks.end(); i!=blocks.begin(); )
758         {
759                 --i;
760                 map<string, StructDeclaration *>::iterator j = (*i)->types.find(var.type);
761                 if(j!=(*i)->types.end())
762                         var.type_declaration = j->second;
763         }
764
765         if(!block_interface.empty() && var.interface.empty())
766                 var.interface = block_interface;
767
768         TraversingVisitor::visit(var);
769         blocks.back()->variables[var.name] = &var;
770         if(anonymous && blocks.size()>1)
771                 blocks[blocks.size()-2]->variables[var.name] = &var;
772 }
773
774 void ProgramCompiler::VariableResolver::visit(InterfaceBlock &iface)
775 {
776         SetFlag set(anonymous);
777         SetForScope<string> set2(block_interface, iface.interface);
778         TraversingVisitor::visit(iface);
779 }
780
781
782 void ProgramCompiler::FunctionResolver::visit(FunctionCall &call)
783 {
784         map<string, vector<FunctionDeclaration *> >::iterator i = functions.find(call.name);
785         if(i!=functions.end())
786                 call.declaration = i->second.back();
787
788         TraversingVisitor::visit(call);
789 }
790
791 void ProgramCompiler::FunctionResolver::visit(FunctionDeclaration &func)
792 {
793         vector<FunctionDeclaration *> &decls = functions[func.name];
794         if(func.definition)
795         {
796                 for(vector<FunctionDeclaration *>::iterator i=decls.begin(); i!=decls.end(); ++i)
797                         (*i)->definition = func.definition;
798                 decls.clear();
799                 decls.push_back(&func);
800         }
801         else if(!decls.empty() && decls.back()->definition)
802                 func.definition = decls.back()->definition;
803         else
804                 decls.push_back(&func);
805
806         TraversingVisitor::visit(func);
807 }
808
809
810 ProgramCompiler::InterfaceGenerator::InterfaceGenerator():
811         scope_level(0)
812 { }
813
814 string ProgramCompiler::InterfaceGenerator::get_out_prefix(StageType type)
815 {
816         if(type==VERTEX)
817                 return "_vs_out_";
818         else if(type==GEOMETRY)
819                 return "_gs_out_";
820         else
821                 return string();
822 }
823
824 void ProgramCompiler::InterfaceGenerator::apply(Stage &s)
825 {
826         SetForScope<Stage *> set(stage, &s);
827         if(stage->previous)
828                 in_prefix = get_out_prefix(stage->previous->type);
829         out_prefix = get_out_prefix(stage->type);
830         stage->content.visit(*this);
831 }
832
833 void ProgramCompiler::InterfaceGenerator::visit(Block &block)
834 {
835         SetForScope<unsigned> set(scope_level, scope_level+1);
836         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
837         {
838                 (*i)->visit(*this);
839
840                 if(scope_level==1)
841                 {
842                         for(map<string, RefPtr<VariableDeclaration> >::iterator j=iface_declarations.begin(); j!=iface_declarations.end(); ++j)
843                         {
844                                 list<RefPtr<Node> >::iterator k = block.body.insert(i, j->second);
845                                 (*k)->visit(*this);
846                         }
847                         iface_declarations.clear();
848                 }
849
850                 apply_and_increment(block, i);
851         }
852 }
853
854 string ProgramCompiler::InterfaceGenerator::change_prefix(const string &name, const string &prefix) const
855 {
856         unsigned offset = (name.compare(0, in_prefix.size(), in_prefix) ? 0 : in_prefix.size());
857         return prefix+name.substr(offset);
858 }
859
860 bool ProgramCompiler::InterfaceGenerator::generate_interface(VariableDeclaration &var, const string &iface, const string &name)
861 {
862         const map<string, VariableDeclaration *> &stage_vars = (iface=="in" ? stage->in_variables : stage->out_variables);
863         if(stage_vars.count(name) || iface_declarations.count(name))
864                 return false;
865
866         VariableDeclaration* iface_var = new VariableDeclaration;
867         iface_var->sampling = var.sampling;
868         iface_var->interface = iface;
869         iface_var->type = var.type;
870         iface_var->type_declaration = var.type_declaration;
871         iface_var->name = name;
872         if(stage->type==GEOMETRY)
873                 iface_var->array = ((var.array && var.interface!="in") || iface=="in");
874         else
875                 iface_var->array = var.array;
876         if(iface_var->array)
877                 iface_var->array_size = var.array_size;
878         if(iface=="in")
879                 iface_var->linked_declaration = &var;
880         iface_declarations[name] = iface_var;
881
882         return true;
883 }
884
885 void ProgramCompiler::InterfaceGenerator::insert_assignment(const string &left, ProgramSyntax::Expression *right)
886 {
887         Assignment *assign = new Assignment;
888         VariableReference *ref = new VariableReference;
889         ref->name = left;
890         assign->left = ref;
891         assign->oper = "=";
892         assign->right = right;
893
894         ExpressionStatement *stmt = new ExpressionStatement;
895         stmt->expression = assign;
896         stmt->visit(*this);
897         insert_nodes.push_back(stmt);
898 }
899
900 void ProgramCompiler::InterfaceGenerator::visit(VariableReference &var)
901 {
902         if(var.declaration || !stage->previous)
903                 return;
904         if(iface_declarations.count(var.name))
905                 return;
906
907         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
908         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
909         if(i==prev_out.end())
910                 i = prev_out.find(in_prefix+var.name);
911         if(i!=prev_out.end())
912         {
913                 generate_interface(*i->second, "in", i->second->name);
914                 var.name = i->second->name;
915         }
916 }
917
918 void ProgramCompiler::InterfaceGenerator::visit(VariableDeclaration &var)
919 {
920         if(var.interface=="out")
921         {
922                 if(scope_level==1)
923                         stage->out_variables[var.name] = &var;
924                 else if(generate_interface(var, "out", change_prefix(var.name, string())))
925                 {
926                         remove_node = true;
927                         if(var.init_expression)
928                         {
929                                 insert_assignment(var.name, var.init_expression->clone());
930                                 return;
931                         }
932                 }
933         }
934         else if(var.interface=="in")
935         {
936                 stage->in_variables[var.name] = &var;
937                 if(var.linked_declaration)
938                         var.linked_declaration->linked_declaration = &var;
939                 else if(stage->previous)
940                 {
941                         const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
942                         map<string, VariableDeclaration *>::const_iterator i = prev_out.find(var.name);
943                         if(i!=prev_out.end())
944                         {
945                                 var.linked_declaration = i->second;
946                                 i->second->linked_declaration = &var;
947                         }
948                 }
949         }
950
951         TraversingVisitor::visit(var);
952 }
953
954 void ProgramCompiler::InterfaceGenerator::visit(Passthrough &pass)
955 {
956         vector<VariableDeclaration *> pass_vars;
957
958         for(map<string, VariableDeclaration *>::const_iterator i=stage->in_variables.begin(); i!=stage->in_variables.end(); ++i)
959                 pass_vars.push_back(i->second);
960         for(map<string, RefPtr<VariableDeclaration> >::const_iterator i=iface_declarations.begin(); i!=iface_declarations.end(); ++i)
961                 if(i->second->interface=="in")
962                         pass_vars.push_back(i->second.get());
963
964         if(stage->previous)
965         {
966                 const map<string, VariableDeclaration *> &prev_out = stage->previous->out_variables;
967                 for(map<string, VariableDeclaration *>::const_iterator i=prev_out.begin(); i!=prev_out.end(); ++i)
968                 {
969                         bool linked = false;
970                         for(vector<VariableDeclaration *>::const_iterator j=pass_vars.begin(); (!linked && j!=pass_vars.end()); ++j)
971                                 linked = ((*j)->linked_declaration==i->second);
972
973                         if(!linked && generate_interface(*i->second, "in", i->second->name))
974                                 pass_vars.push_back(i->second);
975                 }
976         }
977
978         if(stage->type==GEOMETRY)
979         {
980                 VariableReference *ref = new VariableReference;
981                 ref->name = "gl_in";
982
983                 BinaryExpression *subscript = new BinaryExpression;
984                 subscript->left = ref;
985                 subscript->oper = "[";
986                 subscript->right = pass.subscript;
987                 subscript->after = "]";
988
989                 MemberAccess *memacc = new MemberAccess;
990                 memacc->left = subscript;
991                 memacc->member = "gl_Position";
992
993                 insert_assignment("gl_Position", memacc);
994         }
995
996         for(vector<VariableDeclaration *>::const_iterator i=pass_vars.begin(); i!=pass_vars.end(); ++i)
997         {
998                 string out_name = change_prefix((*i)->name, out_prefix);
999                 generate_interface(**i, "out", out_name);
1000
1001                 VariableReference *ref = new VariableReference;
1002                 ref->name = (*i)->name;
1003                 if(pass.subscript)
1004                 {
1005                         BinaryExpression *subscript = new BinaryExpression;
1006                         subscript->left = ref;
1007                         subscript->oper = "[";
1008                         subscript->right = pass.subscript;
1009                         subscript->after = "]";
1010                         insert_assignment(out_name, subscript);
1011                 }
1012                 else
1013                         insert_assignment(out_name, ref);
1014         }
1015
1016         remove_node = true;
1017 }
1018
1019
1020 ProgramCompiler::DeclarationReorderer::DeclarationReorderer():
1021         scope_level(0),
1022         kind(NO_DECLARATION)
1023 { }
1024
1025 void ProgramCompiler::DeclarationReorderer::visit(FunctionCall &call)
1026 {
1027         FunctionDeclaration *def = call.declaration;
1028         if(def)
1029                 def = def->definition;
1030         if(def && !ordered_funcs.count(def))
1031                 needed_funcs.insert(def);
1032 }
1033
1034 void ProgramCompiler::DeclarationReorderer::visit(Block &block)
1035 {
1036         SetForScope<unsigned> set(scope_level, scope_level+1);
1037         if(scope_level>1)
1038                 return Visitor::visit(block);
1039
1040         list<RefPtr<Node> >::iterator struct_insert_point = block.body.end();
1041         list<RefPtr<Node> >::iterator variable_insert_point = block.body.end();
1042         list<RefPtr<Node> >::iterator function_insert_point = block.body.end();
1043         unsigned unordered_func_count = 0;
1044         bool ordered_any_funcs = false;
1045
1046         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
1047         {
1048                 kind = NO_DECLARATION;
1049                 (*i)->visit(*this);
1050
1051                 bool moved = false;
1052                 if(kind==STRUCT && struct_insert_point!=block.body.end())
1053                 {
1054                         block.body.insert(struct_insert_point, *i);
1055                         moved = true;
1056                 }
1057                 else if(kind>STRUCT && struct_insert_point==block.body.end())
1058                         struct_insert_point = i;
1059
1060                 if(kind==VARIABLE && variable_insert_point!=block.body.end())
1061                 {
1062                         block.body.insert(variable_insert_point, *i);
1063                         moved = true;
1064                 }
1065                 else if(kind>VARIABLE && variable_insert_point==block.body.end())
1066                         variable_insert_point = i;
1067
1068                 if(kind==FUNCTION)
1069                 {
1070                         if(function_insert_point==block.body.end())
1071                                 function_insert_point = i;
1072
1073                         if(needed_funcs.empty())
1074                         {
1075                                 ordered_funcs.insert(i->get());
1076                                 if(i!=function_insert_point)
1077                                 {
1078                                         block.body.insert(function_insert_point, *i);
1079                                         moved = true;
1080                                 }
1081                                 else
1082                                         ++function_insert_point;
1083                                 ordered_any_funcs = true;
1084                         }
1085                         else
1086                                 ++unordered_func_count;
1087                 }
1088
1089                 if(moved)
1090                 {
1091                         if(function_insert_point==i)
1092                                 ++function_insert_point;
1093                         block.body.erase(i++);
1094                 }
1095                 else
1096                         ++i;
1097
1098                 if(i==block.body.end() && unordered_func_count)
1099                 {
1100                         if(!ordered_any_funcs)
1101                                 // A subset of the remaining functions forms a recursive loop
1102                                 /* TODO pick a function and move it up, adding any necessary
1103                                 declarations */
1104                                 break;
1105
1106                         i = function_insert_point;
1107                         unordered_func_count = 0;
1108                 }
1109         }
1110 }
1111
1112 void ProgramCompiler::DeclarationReorderer::visit(ProgramSyntax::VariableDeclaration &var)
1113 {
1114         Visitor::visit(var);
1115         kind = VARIABLE;
1116 }
1117
1118 void ProgramCompiler::DeclarationReorderer::visit(FunctionDeclaration &func)
1119 {
1120         needed_funcs.clear();
1121         func.body.visit(*this);
1122         needed_funcs.erase(&func);
1123         kind = FUNCTION;
1124 }
1125
1126
1127 ProgramCompiler::InlineableFunctionLocator::InlineableFunctionLocator():
1128         in_function(0)
1129 { }
1130
1131 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionCall &call)
1132 {
1133         FunctionDeclaration *def = call.declaration;
1134         if(def && def->definition!=def)
1135                 def = def->definition;
1136
1137         if(def)
1138         {
1139                 unsigned &count = refcounts[def];
1140                 ++count;
1141                 if(count>1 || def==in_function)
1142                         inlineable.erase(def);
1143         }
1144
1145         TraversingVisitor::visit(call);
1146 }
1147
1148 void ProgramCompiler::InlineableFunctionLocator::visit(FunctionDeclaration &func)
1149 {
1150         unsigned &count = refcounts[func.definition];
1151         if(!count && func.parameters.empty())
1152                 inlineable.insert(func.definition);
1153
1154         SetForScope<FunctionDeclaration *> set(in_function, &func);
1155         TraversingVisitor::visit(func);
1156 }
1157
1158
1159 ProgramCompiler::FunctionInliner::FunctionInliner():
1160         extract_result(0)
1161 { }
1162
1163 ProgramCompiler::FunctionInliner::FunctionInliner(const set<FunctionDeclaration *> &in):
1164         inlineable(in),
1165         extract_result(0)
1166 { }
1167
1168 void ProgramCompiler::FunctionInliner::visit_and_inline(RefPtr<Expression> &ptr)
1169 {
1170         inline_result = 0;
1171         ptr->visit(*this);
1172         if(inline_result)
1173                 ptr = inline_result;
1174 }
1175
1176 void ProgramCompiler::FunctionInliner::visit(Block &block)
1177 {
1178         if(extract_result)
1179                 --extract_result;
1180
1181         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); ++i)
1182         {
1183                 (*i)->visit(*this);
1184                 if(extract_result)
1185                         --extract_result;
1186         }
1187 }
1188
1189 void ProgramCompiler::FunctionInliner::visit(UnaryExpression &unary)
1190 {
1191         visit_and_inline(unary.expression);
1192         inline_result = 0;
1193 }
1194
1195 void ProgramCompiler::FunctionInliner::visit(BinaryExpression &binary)
1196 {
1197         visit_and_inline(binary.left);
1198         visit_and_inline(binary.right);
1199         inline_result = 0;
1200 }
1201
1202 void ProgramCompiler::FunctionInliner::visit(MemberAccess &memacc)
1203 {
1204         visit_and_inline(memacc.left);
1205         inline_result = 0;
1206 }
1207
1208 void ProgramCompiler::FunctionInliner::visit(FunctionCall &call)
1209 {
1210         for(vector<RefPtr<Expression> >::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
1211                 visit_and_inline(*i);
1212
1213         FunctionDeclaration *def = call.declaration;
1214         if(def && def->definition!=def)
1215                 def = def->definition;
1216
1217         if(def && inlineable.count(def))
1218         {
1219                 extract_result = 2;
1220                 def->visit(*this);
1221         }
1222         else
1223                 inline_result = 0;
1224 }
1225
1226 void ProgramCompiler::FunctionInliner::visit(Return &ret)
1227 {
1228         TraversingVisitor::visit(ret);
1229
1230         if(extract_result)
1231                 inline_result = ret.expression->clone();
1232 }
1233
1234
1235 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator():
1236         variable_values(0),
1237         result(0.0f),
1238         result_valid(false)
1239 { }
1240
1241 ProgramCompiler::ExpressionEvaluator::ExpressionEvaluator(const ValueMap &v):
1242         variable_values(&v),
1243         result(0.0f),
1244         result_valid(false)
1245 { }
1246
1247 void ProgramCompiler::ExpressionEvaluator::visit(Literal &literal)
1248 {
1249         if(literal.token=="true")
1250                 result = 1.0f;
1251         else if(literal.token=="false")
1252                 result = 0.0f;
1253         else
1254                 result = lexical_cast<float>(literal.token);
1255         result_valid = true;
1256 }
1257
1258 void ProgramCompiler::ExpressionEvaluator::visit(ParenthesizedExpression &parexp)
1259 {
1260         parexp.expression->visit(*this);
1261 }
1262
1263 void ProgramCompiler::ExpressionEvaluator::visit(VariableReference &var)
1264 {
1265         if(!var.declaration)
1266                 return;
1267
1268         if(variable_values)
1269         {
1270                 ValueMap::const_iterator i = variable_values->find(var.declaration);
1271                 if(i!=variable_values->end())
1272                         i->second->visit(*this);
1273         }
1274         else if(var.declaration->init_expression)
1275                 var.declaration->init_expression->visit(*this);
1276 }
1277
1278 void ProgramCompiler::ExpressionEvaluator::visit(UnaryExpression &unary)
1279 {
1280         result_valid = false;
1281         unary.expression->visit(*this);
1282         if(!result_valid)
1283                 return;
1284
1285         if(unary.oper=="!")
1286                 result = !result;
1287         else
1288                 result_valid = false;
1289 }
1290
1291 void ProgramCompiler::ExpressionEvaluator::visit(BinaryExpression &binary)
1292 {
1293         result_valid = false;
1294         binary.left->visit(*this);
1295         if(!result_valid)
1296                 return;
1297
1298         float left_result = result;
1299         result_valid = false;
1300         binary.right->visit(*this);
1301         if(!result_valid)
1302                 return;
1303
1304         if(binary.oper=="<")
1305                 result = (left_result<result);
1306         else if(binary.oper=="<=")
1307                 result = (left_result<=result);
1308         else if(binary.oper==">")
1309                 result = (left_result>result);
1310         else if(binary.oper==">=")
1311                 result = (left_result>=result);
1312         else if(binary.oper=="==")
1313                 result = (left_result==result);
1314         else if(binary.oper=="!=")
1315                 result = (left_result!=result);
1316         else if(binary.oper=="&&")
1317                 result = (left_result && result);
1318         else if(binary.oper=="||")
1319                 result = (left_result || result);
1320         else
1321                 result_valid = false;
1322 }
1323
1324
1325 ProgramCompiler::ConstantConditionEliminator::ConstantConditionEliminator():
1326         scope_level(0),
1327         record_only(false)
1328 { }
1329
1330 void ProgramCompiler::ConstantConditionEliminator::visit(Block &block)
1331 {
1332         SetForScope<unsigned> set(scope_level, scope_level+1);
1333         BlockModifier::visit(block);
1334
1335         for(map<string, VariableDeclaration *>::const_iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
1336                 variable_values.erase(i->second);
1337 }
1338
1339 void ProgramCompiler::ConstantConditionEliminator::visit(UnaryExpression &unary)
1340 {
1341         if(VariableReference *var = dynamic_cast<VariableReference *>(unary.expression.get()))
1342                 if(unary.oper=="++" || unary.oper=="--")
1343                         variable_values.erase(var->declaration);
1344 }
1345
1346 void ProgramCompiler::ConstantConditionEliminator::visit(Assignment &assign)
1347 {
1348         variable_values.erase(assign.target_declaration);
1349 }
1350
1351 void ProgramCompiler::ConstantConditionEliminator::visit(VariableDeclaration &var)
1352 {
1353         if(var.constant || scope_level>1)
1354                 variable_values[&var] = var.init_expression.get();
1355 }
1356
1357 void ProgramCompiler::ConstantConditionEliminator::visit(Conditional &cond)
1358 {
1359         if(!record_only)
1360         {
1361                 ExpressionEvaluator eval(variable_values);
1362                 cond.condition->visit(eval);
1363                 if(eval.result_valid)
1364                 {
1365                         flatten_block(eval.result ? cond.body : cond.else_body);
1366                         return;
1367                 }
1368         }
1369
1370         TraversingVisitor::visit(cond);
1371 }
1372
1373 void ProgramCompiler::ConstantConditionEliminator::visit(Iteration &iter)
1374 {
1375         if(!record_only)
1376         {
1377                 if(iter.condition)
1378                 {
1379                         /* If the loop condition is always false on the first iteration, the
1380                         entire loop can be removed */
1381                         if(iter.init_statement)
1382                                 iter.init_statement->visit(*this);
1383                         ExpressionEvaluator eval(variable_values);
1384                         iter.condition->visit(eval);
1385                         if(eval.result_valid && !eval.result)
1386                         {
1387                                 remove_node = true;
1388                                 return;
1389                         }
1390                 }
1391
1392                 /* Record all assignments that occur inside the loop body so those
1393                 variables won't be considered as constant */
1394                 SetFlag set_record(record_only);
1395                 TraversingVisitor::visit(iter);
1396         }
1397
1398         TraversingVisitor::visit(iter);
1399
1400         if(VariableDeclaration *init_decl = dynamic_cast<VariableDeclaration *>(iter.init_statement.get()))
1401                 variable_values.erase(init_decl);
1402 }
1403
1404
1405 ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
1406         aggregate(0),
1407         assignment(0),
1408         assignment_target(false),
1409         global_scope(true)
1410 { }
1411
1412 void ProgramCompiler::UnusedVariableLocator::apply(Stage &s)
1413 {
1414         variables.push_back(BlockVariableMap());
1415         Visitor::apply(s);
1416         BlockVariableMap &global_variables = variables.back();
1417         for(BlockVariableMap::iterator i=global_variables.begin(); i!=global_variables.end(); ++i)
1418         {
1419                 if(i->first->interface=="out" && (s.type==FRAGMENT || i->first->linked_declaration || !i->first->name.compare(0, 3, "gl_")))
1420                         continue;
1421                 if(!i->second.referenced)
1422                 {
1423                         unused_nodes.insert(i->first);
1424                         clear_assignments(i->second, true);
1425                 }
1426         }
1427         variables.pop_back();
1428 }
1429
1430 void ProgramCompiler::UnusedVariableLocator::visit(VariableReference &var)
1431 {
1432         map<VariableDeclaration *, Node *>::iterator i = aggregates.find(var.declaration);
1433         if(i!=aggregates.end())
1434                 unused_nodes.erase(i->second);
1435
1436         if(var.declaration && !assignment_target)
1437         {
1438                 VariableInfo &var_info = variables.back()[var.declaration];
1439                 var_info.assignments.clear();
1440                 var_info.referenced = true;
1441         }
1442 }
1443
1444 void ProgramCompiler::UnusedVariableLocator::visit(MemberAccess &memacc)
1445 {
1446         TraversingVisitor::visit(memacc);
1447         unused_nodes.erase(memacc.declaration);
1448 }
1449
1450 void ProgramCompiler::UnusedVariableLocator::visit(BinaryExpression &binary)
1451 {
1452         if(binary.oper=="[")
1453         {
1454                 binary.left->visit(*this);
1455                 SetForScope<bool> set(assignment_target, false);
1456                 binary.right->visit(*this);
1457         }
1458         else
1459                 TraversingVisitor::visit(binary);
1460 }
1461
1462 void ProgramCompiler::UnusedVariableLocator::visit(Assignment &assign)
1463 {
1464         {
1465                 SetForScope<bool> set(assignment_target, !assign.self_referencing);
1466                 assign.left->visit(*this);
1467         }
1468         assign.right->visit(*this);
1469         assignment = &assign;
1470 }
1471
1472 void ProgramCompiler::UnusedVariableLocator::record_assignment(VariableDeclaration &var, Node &node, bool self_ref)
1473 {
1474         VariableInfo &var_info = variables.back()[&var];
1475         if(!self_ref)
1476                 clear_assignments(var_info, true);
1477         var_info.assignments.push_back(&node);
1478         var_info.conditionally_assigned = false;
1479 }
1480
1481 void ProgramCompiler::UnusedVariableLocator::clear_assignments(VariableInfo &var_info, bool mark_unused)
1482 {
1483         if(mark_unused)
1484         {
1485                 for(vector<Node *>::iterator i=var_info.assignments.begin(); i!=var_info.assignments.end(); ++i)
1486                         unused_nodes.insert(*i);
1487         }
1488         var_info.assignments.clear();
1489 }
1490
1491 void ProgramCompiler::UnusedVariableLocator::visit(ExpressionStatement &expr)
1492 {
1493         assignment = 0;
1494         TraversingVisitor::visit(expr);
1495         if(assignment && assignment->target_declaration)
1496                 record_assignment(*assignment->target_declaration, expr, assignment->self_referencing);
1497 }
1498
1499 void ProgramCompiler::UnusedVariableLocator::visit(StructDeclaration &strct)
1500 {
1501         SetForScope<Node *> set(aggregate, &strct);
1502         unused_nodes.insert(&strct);
1503         TraversingVisitor::visit(strct);
1504 }
1505
1506 void ProgramCompiler::UnusedVariableLocator::visit(VariableDeclaration &var)
1507 {
1508         if(aggregate)
1509                 aggregates[&var] = aggregate;
1510         else
1511         {
1512                 variables.back()[&var].local = true;
1513                 if(var.init_expression)
1514                         record_assignment(var, *var.init_expression, false);
1515         }
1516         unused_nodes.erase(var.type_declaration);
1517         TraversingVisitor::visit(var);
1518 }
1519
1520 void ProgramCompiler::UnusedVariableLocator::visit(InterfaceBlock &iface)
1521 {
1522         SetForScope<Node *> set(aggregate, &iface);
1523         unused_nodes.insert(&iface);
1524         TraversingVisitor::visit(iface);
1525 }
1526
1527 void ProgramCompiler::UnusedVariableLocator::visit(FunctionDeclaration &func)
1528 {
1529         variables.push_back(BlockVariableMap());
1530
1531         {
1532                 SetForScope<bool> set(global_scope, false);
1533                 for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1534                         (*i)->visit(*this);
1535                 func.body.visit(*this);
1536         }
1537
1538         BlockVariableMap &block_variables = variables.back();
1539         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1540                 i->second.conditionally_assigned = true;
1541         for(vector<RefPtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1542                 block_variables[i->get()].referenced = true;
1543         merge_down_variables();
1544 }
1545
1546 void ProgramCompiler::UnusedVariableLocator::merge_down_variables()
1547 {
1548         BlockVariableMap &parent_variables = variables[variables.size()-2];
1549         BlockVariableMap &block_variables = variables.back();
1550         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1551         {
1552                 if(i->second.local)
1553                 {
1554                         if(!i->second.referenced)
1555                                 unused_nodes.insert(i->first);
1556                         clear_assignments(i->second, true);
1557                         continue;
1558                 }
1559
1560                 BlockVariableMap::iterator j = parent_variables.find(i->first);
1561                 if(j==parent_variables.end())
1562                         parent_variables.insert(*i);
1563                 else
1564                 {
1565                         if(i->second.referenced || !i->second.conditionally_assigned)
1566                                 clear_assignments(j->second, !i->second.referenced);
1567                         j->second.conditionally_assigned = i->second.conditionally_assigned;
1568                         j->second.referenced |= i->second.referenced;
1569                         j->second.assignments.insert(j->second.assignments.end(), i->second.assignments.begin(), i->second.assignments.end());
1570                 }
1571         }
1572         variables.pop_back();
1573 }
1574
1575 void ProgramCompiler::UnusedVariableLocator::visit(Conditional &cond)
1576 {
1577         cond.condition->visit(*this);
1578         variables.push_back(BlockVariableMap());
1579         cond.body.visit(*this);
1580
1581         BlockVariableMap if_variables;
1582         swap(variables.back(), if_variables);
1583         cond.else_body.visit(*this);
1584
1585         BlockVariableMap &else_variables = variables.back();
1586         for(BlockVariableMap::iterator i=else_variables.begin(); i!=else_variables.end(); ++i)
1587         {
1588                 BlockVariableMap::iterator j = if_variables.find(i->first);
1589                 if(j!=if_variables.end())
1590                 {
1591                         i->second.assignments.insert(i->second.assignments.end(), j->second.assignments.begin(), j->second.assignments.end());
1592                         i->second.conditionally_assigned |= j->second.conditionally_assigned;
1593                         if_variables.erase(j);
1594                 }
1595                 else
1596                         i->second.conditionally_assigned = true;
1597         }
1598
1599         for(BlockVariableMap::iterator i=if_variables.begin(); i!=if_variables.end(); ++i)
1600         {
1601                 i->second.conditionally_assigned = true;
1602                 else_variables.insert(*i);
1603         }
1604
1605         merge_down_variables();
1606 }
1607
1608 void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
1609 {
1610         variables.push_back(BlockVariableMap());
1611         TraversingVisitor::visit(iter);
1612
1613         BlockVariableMap &block_variables = variables.back();
1614         for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
1615                 if(!i->second.local && i->second.referenced)
1616                         i->second.assignments.clear();
1617
1618         merge_down_variables();
1619 }
1620
1621
1622 ProgramCompiler::UnusedVariableLocator::VariableInfo::VariableInfo():
1623         local(false),
1624         conditionally_assigned(false),
1625         referenced(false)
1626 { }
1627
1628
1629 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionCall &call)
1630 {
1631         TraversingVisitor::visit(call);
1632
1633         unused_nodes.erase(call.declaration);
1634         if(call.declaration && call.declaration->definition!=call.declaration)
1635                 used_definitions.insert(call.declaration->definition);
1636 }
1637
1638 void ProgramCompiler::UnusedFunctionLocator::visit(FunctionDeclaration &func)
1639 {
1640         TraversingVisitor::visit(func);
1641
1642         if((func.name!="main" || func.body.body.empty()) && !used_definitions.count(&func))
1643                 unused_nodes.insert(&func);
1644 }
1645
1646
1647 ProgramCompiler::NodeRemover::NodeRemover(const set<Node *> &r):
1648         to_remove(r)
1649 { }
1650
1651 void ProgramCompiler::NodeRemover::visit(Block &block)
1652 {
1653         for(list<RefPtr<Node> >::iterator i=block.body.begin(); i!=block.body.end(); )
1654         {
1655                 (*i)->visit(*this);
1656                 if(to_remove.count(i->get()))
1657                         block.body.erase(i++);
1658                 else
1659                         ++i;
1660         }
1661 }
1662
1663 void ProgramCompiler::NodeRemover::visit(VariableDeclaration &var)
1664 {
1665         if(to_remove.count(&var))
1666         {
1667                 stage->in_variables.erase(var.name);
1668                 stage->out_variables.erase(var.name);
1669                 stage->locations.erase(var.name);
1670                 if(var.linked_declaration)
1671                         var.linked_declaration->linked_declaration = 0;
1672         }
1673         else if(var.init_expression && to_remove.count(var.init_expression.get()))
1674                 var.init_expression = 0;
1675 }
1676
1677 void ProgramCompiler::NodeRemover::visit(Iteration &iter)
1678 {
1679         if(to_remove.count(iter.init_statement.get()))
1680                 iter.init_statement = 0;
1681 }
1682
1683
1684 void ProgramCompiler::PrecisionRemover::visit(Precision &)
1685 {
1686         remove_node = true;
1687 }
1688
1689 void ProgramCompiler::PrecisionRemover::visit(VariableDeclaration &var)
1690 {
1691         var.precision.clear();
1692 }
1693
1694
1695 ProgramCompiler::DefaultPrecisionGenerator::DefaultPrecisionGenerator():
1696         toplevel(true)
1697 { }
1698
1699 void ProgramCompiler::DefaultPrecisionGenerator::visit(Block &block)
1700 {
1701         if(toplevel)
1702         {
1703                 SetForScope<bool> set(toplevel, false);
1704                 BlockModifier::visit(block);
1705         }
1706         else
1707                 Visitor::visit(block);
1708 }
1709
1710 void ProgramCompiler::DefaultPrecisionGenerator::visit(Precision &prec)
1711 {
1712         have_default.insert(prec.type);
1713 }
1714
1715 void ProgramCompiler::DefaultPrecisionGenerator::visit(VariableDeclaration &var)
1716 {
1717         if(var.type_declaration)
1718                 return;
1719
1720         string type = var.type;
1721         if(!type.compare(0, 3, "vec") || !type.compare(0, 3, "mat"))
1722                 type = "float";
1723         else if(!type.compare(0, 3, "ivec") || type=="uint")
1724                 type = "int";
1725
1726         if(!have_default.count(type))
1727         {
1728                 Precision *prec = new Precision;
1729                 if(!type.compare(0, 7, "sampler"))
1730                         prec->precision = "lowp";
1731                 else if(stage->type==FRAGMENT)
1732                         prec->precision = "mediump";
1733                 else
1734                         prec->precision = "highp";
1735                 prec->type = type;
1736                 insert_nodes.push_back(prec);
1737
1738                 have_default.insert(type);
1739         }
1740 }
1741
1742
1743 ProgramCompiler::LegacyConverter::LegacyConverter():
1744         target_api(get_gl_api()),
1745         target_version(get_glsl_version()),
1746         frag_out(0)
1747 { }
1748
1749 ProgramCompiler::LegacyConverter::LegacyConverter(const Version &v):
1750         target_api(get_gl_api()),
1751         target_version(v),
1752         frag_out(0)
1753 { }
1754
1755 bool ProgramCompiler::LegacyConverter::check_version(const Version &feature_version) const
1756 {
1757         if(target_version<feature_version)
1758                 return false;
1759         else if(stage->required_version<feature_version)
1760                 stage->required_version = feature_version;
1761
1762         return true;
1763 }
1764
1765 bool ProgramCompiler::LegacyConverter::supports_unified_interface_syntax() const
1766 {
1767         if(target_api==OPENGL_ES2)
1768                 return check_version(Version(3, 0));
1769         else
1770                 return check_version(Version(1, 30));
1771 }
1772
1773 void ProgramCompiler::LegacyConverter::visit(VariableReference &var)
1774 {
1775         if(var.declaration==frag_out && !supports_unified_interface_syntax())
1776         {
1777                 var.name = "gl_FragColor";
1778                 var.declaration = 0;
1779                 type = "vec4";
1780         }
1781         else if(var.declaration)
1782                 type = var.declaration->type;
1783         else
1784                 type = string();
1785 }
1786
1787 void ProgramCompiler::LegacyConverter::visit(Assignment &assign)
1788 {
1789         TraversingVisitor::visit(assign);
1790         if(assign.target_declaration==frag_out && !supports_unified_interface_syntax())
1791                 assign.target_declaration = 0;
1792 }
1793
1794 bool ProgramCompiler::LegacyConverter::supports_unified_sampling_functions() const
1795 {
1796         if(target_api==OPENGL_ES2)
1797                 return check_version(Version(3, 0));
1798         else
1799                 return check_version(Version(1, 30));
1800 }
1801
1802 void ProgramCompiler::LegacyConverter::visit(FunctionCall &call)
1803 {
1804         if(call.name=="texture" && !call.declaration && !supports_unified_sampling_functions())
1805         {
1806                 vector<RefPtr<Expression> >::iterator i = call.arguments.begin();
1807                 if(i!=call.arguments.end())
1808                 {
1809                         (*i)->visit(*this);
1810                         if(type=="sampler1D")
1811                                 call.name = "texture1D";
1812                         else if(type=="sampler2D")
1813                                 call.name = "texture2D";
1814                         else if(type=="sampler3D")
1815                                 call.name = "texture3D";
1816                         else if(type=="sampler1DShadow")
1817                                 call.name = "shadow1D";
1818                         else if(type=="sampler2DShadow")
1819                                 call.name = "shadow2D";
1820
1821                         for(; i!=call.arguments.end(); ++i)
1822                                 (*i)->visit(*this);
1823                 }
1824         }
1825         else
1826                 TraversingVisitor::visit(call);
1827 }
1828
1829 bool ProgramCompiler::LegacyConverter::supports_interface_layouts() const
1830 {
1831         if(target_api==OPENGL_ES2)
1832                 return check_version(Version(3, 0));
1833         else
1834                 return check_version(Version(3, 30));
1835 }
1836
1837 bool ProgramCompiler::LegacyConverter::supports_centroid_sampling() const
1838 {
1839         if(target_api==OPENGL_ES2)
1840                 return check_version(Version(3, 0));
1841         else
1842                 return check_version(Version(1, 20));
1843 }
1844
1845 bool ProgramCompiler::LegacyConverter::supports_sample_sampling() const
1846 {
1847         if(target_api==OPENGL_ES2)
1848                 return check_version(Version(3, 20));
1849         else
1850                 return check_version(Version(4, 0));
1851 }
1852
1853 void ProgramCompiler::LegacyConverter::visit(VariableDeclaration &var)
1854 {
1855         if(var.layout && !supports_interface_layouts())
1856         {
1857                 vector<Layout::Qualifier>::iterator i;
1858                 for(i=var.layout->qualifiers.begin(); (i!=var.layout->qualifiers.end() && i->identifier!="location"); ++i) ;
1859                 if(i!=var.layout->qualifiers.end())
1860                 {
1861                         unsigned location = lexical_cast<unsigned>(i->value);
1862                         if(stage->type==VERTEX && var.interface=="in")
1863                         {
1864                                 stage->locations[var.name] = location;
1865                                 var.layout->qualifiers.erase(i);
1866                         }
1867                         else if(stage->type==FRAGMENT && var.interface=="out")
1868                         {
1869                                 if(location!=0)
1870                                         static Require _req(EXT_gpu_shader4);
1871                                 stage->locations[var.name] = location;
1872                                 var.layout->qualifiers.erase(i);
1873                         }
1874
1875                         if(var.layout->qualifiers.empty())
1876                                 var.layout = 0;
1877                 }
1878         }
1879
1880         if(var.sampling=="centroid")
1881         {
1882                 if(!supports_centroid_sampling())
1883                         var.sampling = string();
1884         }
1885         else if(var.sampling=="sample")
1886         {
1887                 if(!supports_sample_sampling())
1888                         var.sampling = string();
1889         }
1890
1891         if((var.interface=="in" || var.interface=="out") && !supports_unified_interface_syntax())
1892         {
1893                 if(stage->type==FRAGMENT && var.interface=="out")
1894                 {
1895                         frag_out = &var;
1896                         remove_node = true;
1897                 }
1898         }
1899
1900         TraversingVisitor::visit(var);
1901 }
1902
1903 bool ProgramCompiler::LegacyConverter::supports_interface_blocks(const string &iface) const
1904 {
1905         if(target_api==OPENGL_ES2)
1906         {
1907                 if(iface=="uniform")
1908                         return check_version(Version(3, 0));
1909                 else
1910                         return check_version(Version(3, 20));
1911         }
1912         else
1913                 return check_version(Version(1, 50));
1914 }
1915
1916 void ProgramCompiler::LegacyConverter::visit(InterfaceBlock &iface)
1917 {
1918         if(!supports_interface_blocks(iface.interface))
1919                 flatten_block(iface.members);
1920 }
1921
1922 } // namespace GL
1923 } // namespace Msp