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