1 #include <msp/core/raii.h>
2 #include <msp/strings/format.h>
12 ConstantSpecializer::ConstantSpecializer():
16 void ConstantSpecializer::apply(Stage &stage, const map<string, int> &v)
19 stage.content.visit(*this);
22 void ConstantSpecializer::visit(VariableDeclaration &var)
24 bool specializable = false;
27 vector<Layout::Qualifier> &qualifiers = var.layout->qualifiers;
28 for(vector<Layout::Qualifier>::iterator i=qualifiers.begin(); (!specializable && i!=qualifiers.end()); ++i)
29 if(i->name=="constant_id")
35 if(qualifiers.empty())
41 map<string, int>::const_iterator i = values->find(var.name);
44 RefPtr<Literal> literal = new Literal;
47 literal->token = (i->second ? "true" : "false");
48 literal->value = static_cast<bool>(i->second);
50 else if(var.type=="int")
52 literal->token = lexical_cast<string>(i->second);
53 literal->value = i->second;
55 var.init_expression = literal;
61 InlineableFunctionLocator::InlineableFunctionLocator():
66 void InlineableFunctionLocator::visit(FunctionCall &call)
68 FunctionDeclaration *def = call.declaration;
70 def = def->definition;
74 unsigned &count = refcounts[def];
76 /* Don't inline functions which are called more than once or are called
78 if(count>1 || def==current_function)
79 inlineable.erase(def);
82 TraversingVisitor::visit(call);
85 void InlineableFunctionLocator::visit(FunctionDeclaration &func)
87 bool has_out_params = false;
88 for(NodeArray<VariableDeclaration>::const_iterator i=func.parameters.begin(); (!has_out_params && i!=func.parameters.end()); ++i)
89 has_out_params = ((*i)->interface=="out");
91 unsigned &count = refcounts[func.definition];
92 if(count<=1 && !has_out_params)
93 inlineable.insert(func.definition);
95 SetForScope<FunctionDeclaration *> set(current_function, &func);
97 TraversingVisitor::visit(func);
100 void InlineableFunctionLocator::visit(Conditional &cond)
102 TraversingVisitor::visit(cond);
103 inlineable.erase(current_function);
106 void InlineableFunctionLocator::visit(Iteration &iter)
108 TraversingVisitor::visit(iter);
109 inlineable.erase(current_function);
112 void InlineableFunctionLocator::visit(Return &ret)
114 TraversingVisitor::visit(ret);
116 inlineable.erase(current_function);
121 InlineContentInjector::InlineContentInjector():
126 string InlineContentInjector::apply(Stage &stage, FunctionDeclaration &target_func, Block &tgt_blk, const NodeList<Statement>::iterator &ins_pt, FunctionCall &call)
128 source_func = call.declaration->definition;
130 /* Populate referenced_names from the target function so we can rename
131 variables from the inlined function that would conflict. */
133 target_func.visit(*this);
135 /* Inline and rename passes must be interleaved so used variable names are
136 known when inlining the return statement. */
138 staging_block.parent = &tgt_blk;
139 staging_block.variables.clear();
141 std::vector<RefPtr<VariableDeclaration> > params;
142 params.reserve(source_func->parameters.size());
143 for(NodeArray<VariableDeclaration>::iterator i=source_func->parameters.begin(); i!=source_func->parameters.end(); ++i)
145 RefPtr<VariableDeclaration> var = (*i)->clone();
146 var->interface.clear();
148 SetForScope<Pass> set_pass(pass, RENAME);
151 staging_block.body.push_back_nocopy(var);
152 params.push_back(var);
155 for(NodeList<Statement>::iterator i=source_func->body.body.begin(); i!=source_func->body.body.end(); ++i)
157 r_inlined_statement = 0;
159 if(!r_inlined_statement)
160 r_inlined_statement = (*i)->clone();
162 SetForScope<Pass> set_pass(pass, RENAME);
163 r_inlined_statement->visit(*this);
165 staging_block.body.push_back_nocopy(r_inlined_statement);
168 /* Now collect names from the staging block. Local variables that would
169 have conflicted with the target function were renamed earlier. */
171 referenced_names.clear();
172 staging_block.variables.clear();
173 staging_block.visit(*this);
175 /* Rename variables in the target function so they don't interfere with
176 global identifiers used by the source function. */
178 staging_block.parent = source_func->body.parent;
179 target_func.visit(*this);
181 // Put the argument expressions in place after all renaming has been done.
182 for(unsigned i=0; i<source_func->parameters.size(); ++i)
183 params[i]->init_expression = call.arguments[i]->clone();
185 tgt_blk.body.splice(ins_pt, staging_block.body);
187 NodeReorderer().apply(stage, target_func, DependencyCollector().apply(*source_func));
189 return r_result_name;
192 void InlineContentInjector::visit(VariableReference &var)
196 map<string, VariableDeclaration *>::const_iterator i = staging_block.variables.find(var.name);
197 if(i!=staging_block.variables.end())
198 var.name = i->second->name;
200 else if(pass==REFERENCED)
201 referenced_names.insert(var.name);
204 void InlineContentInjector::visit(InterfaceBlockReference &iface)
207 referenced_names.insert(iface.name);
210 void InlineContentInjector::visit(FunctionCall &call)
213 referenced_names.insert(call.name);
214 TraversingVisitor::visit(call);
217 void InlineContentInjector::visit(VariableDeclaration &var)
219 TraversingVisitor::visit(var);
223 /* Check against conflicts with the other context as well as variables
224 already renamed here. */
225 bool conflict = (staging_block.variables.count(var.name) || referenced_names.count(var.name));
226 staging_block.variables[var.name] = &var;
229 string mapped_name = get_unused_variable_name(staging_block, var.name);
230 if(mapped_name!=var.name)
232 staging_block.variables[mapped_name] = &var;
233 var.name = mapped_name;
237 else if(pass==REFERENCED)
238 referenced_names.insert(var.type);
241 void InlineContentInjector::visit(Return &ret)
243 TraversingVisitor::visit(ret);
245 if(pass==INLINE && ret.expression)
247 // Create a new variable to hold the return value of the inlined function.
248 r_result_name = get_unused_variable_name(staging_block, "_return");
249 RefPtr<VariableDeclaration> var = new VariableDeclaration;
250 var->source = ret.source;
251 var->line = ret.line;
252 var->type = source_func->return_type;
253 var->name = r_result_name;
254 var->init_expression = ret.expression->clone();
255 r_inlined_statement = var;
260 FunctionInliner::FunctionInliner():
262 r_any_inlined(false),
263 r_inlined_here(false)
266 bool FunctionInliner::apply(Stage &s)
269 inlineable = InlineableFunctionLocator().apply(s);
270 r_any_inlined = false;
271 s.content.visit(*this);
272 return r_any_inlined;
275 void FunctionInliner::visit(RefPtr<Expression> &ptr)
281 ptr = r_inline_result;
282 r_any_inlined = true;
287 void FunctionInliner::visit(Block &block)
289 SetForScope<Block *> set_block(current_block, &block);
290 SetForScope<NodeList<Statement>::iterator> save_insert_point(insert_point, block.body.begin());
291 for(NodeList<Statement>::iterator i=block.body.begin(); (!r_inlined_here && i!=block.body.end()); ++i)
298 void FunctionInliner::visit(FunctionCall &call)
300 for(NodeArray<Expression>::iterator i=call.arguments.begin(); (!r_inlined_here && i!=call.arguments.end()); ++i)
306 FunctionDeclaration *def = call.declaration;
308 def = def->definition;
310 if(def && inlineable.count(def))
312 string result_name = InlineContentInjector().apply(*stage, *current_function, *current_block, insert_point, call);
314 // This will later get removed by UnusedVariableRemover.
315 if(result_name.empty())
316 result_name = "_msp_unused_from_inline";
318 RefPtr<VariableReference> ref = new VariableReference;
319 ref->name = result_name;
320 r_inline_result = ref;
322 /* Inlined variables need to be resolved before this function can be
324 inlineable.erase(current_function);
325 r_inlined_here = true;
329 void FunctionInliner::visit(FunctionDeclaration &func)
331 SetForScope<FunctionDeclaration *> set_func(current_function, &func);
332 TraversingVisitor::visit(func);
333 r_inlined_here = false;
336 void FunctionInliner::visit(Iteration &iter)
338 /* Visit the initialization statement before entering the loop body so the
339 inlined statements get inserted outside. */
340 if(iter.init_statement)
341 iter.init_statement->visit(*this);
343 SetForScope<Block *> set_block(current_block, &iter.body);
344 /* Skip the condition and loop expression parts because they're not properly
345 inside the body block. Inlining anything into them will require a more
346 comprehensive transformation. */
347 iter.body.visit(*this);
351 ExpressionInliner::ExpressionInliner():
353 r_any_inlined(false),
356 iteration_init(false),
361 bool ExpressionInliner::apply(Stage &s)
363 s.content.visit(*this);
364 return r_any_inlined;
367 void ExpressionInliner::inline_expression(Expression &expr, RefPtr<Expression> &ptr)
370 r_any_inlined = true;
373 void ExpressionInliner::visit(Block &block)
375 TraversingVisitor::visit(block);
377 for(map<string, VariableDeclaration *>::iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
379 map<Assignment::Target, ExpressionInfo>::iterator j = expressions.lower_bound(i->second);
380 for(; (j!=expressions.end() && j->first.declaration==i->second); )
382 if(j->second.expression && j->second.inline_point)
383 inline_expression(*j->second.expression, *j->second.inline_point);
385 expressions.erase(j++);
389 /* Expressions assigned in this block may depend on local variables of the
390 block. If this is a conditionally executed block, the assignments might not
391 always happen. Mark the expressions as not available to any outer blocks. */
392 for(map<Assignment::Target, ExpressionInfo>::iterator i=expressions.begin(); i!=expressions.end(); ++i)
393 if(i->second.assign_scope==&block)
394 i->second.available = false;
397 void ExpressionInliner::visit(RefPtr<Expression> &expr)
401 if(r_ref_info && r_ref_info->expression && r_ref_info->available)
403 if(iteration_body && !r_ref_info->trivial)
405 /* Don't inline non-trivial expressions which were assigned outside
406 an iteration statement. The iteration may run multiple times, which
407 would cause the expression to also be evaluated multiple times. */
408 Block *i = r_ref_info->assign_scope;
409 for(; (i && i!=iteration_body); i=i->parent) ;
414 if(r_ref_info->trivial)
415 inline_expression(*r_ref_info->expression, expr);
417 /* Record the inline point for a non-trivial expression but don't
418 inline it yet. It might turn out it shouldn't be inlined after all. */
419 r_ref_info->inline_point = &expr;
425 void ExpressionInliner::visit(VariableReference &var)
429 map<Assignment::Target, ExpressionInfo>::iterator i = expressions.find(var.declaration);
430 if(i!=expressions.end())
432 /* If a non-trivial expression is referenced multiple times, don't
434 if(i->second.inline_point && !i->second.trivial)
435 i->second.expression = 0;
436 /* Mutating expressions are analogous to self-referencing assignments
437 and prevent inlining. */
439 i->second.expression = 0;
440 r_ref_info = &i->second;
445 void ExpressionInliner::visit(MemberAccess &memacc)
451 void ExpressionInliner::visit(Swizzle &swizzle)
457 void ExpressionInliner::visit(UnaryExpression &unary)
459 SetFlag set_target(mutating, mutating || unary.oper->token[1]=='+' || unary.oper->token[1]=='-');
460 visit(unary.expression);
464 void ExpressionInliner::visit(BinaryExpression &binary)
468 SetFlag clear_target(mutating, false);
474 void ExpressionInliner::visit(Assignment &assign)
477 SetFlag set_target(mutating);
483 map<Assignment::Target, ExpressionInfo>::iterator i = expressions.find(assign.target);
484 if(i!=expressions.end())
486 /* Self-referencing assignments can't be inlined without additional
487 work. Just clear any previous expression. */
488 i->second.expression = (assign.self_referencing ? 0 : assign.right.get());
489 i->second.assign_scope = current_block;
490 i->second.inline_point = 0;
491 i->second.available = true;
497 void ExpressionInliner::visit(TernaryExpression &ternary)
499 visit(ternary.condition);
500 visit(ternary.true_expr);
501 visit(ternary.false_expr);
505 void ExpressionInliner::visit(FunctionCall &call)
507 TraversingVisitor::visit(call);
511 void ExpressionInliner::visit(VariableDeclaration &var)
515 TraversingVisitor::visit(var);
517 bool constant = var.constant;
518 if(constant && var.layout)
520 for(vector<Layout::Qualifier>::const_iterator i=var.layout->qualifiers.begin(); (constant && i!=var.layout->qualifiers.end()); ++i)
521 constant = (i->name!="constant_id");
524 /* Only inline global variables if they're constant and have trivial
525 initializers. Non-constant variables could change in ways which are hard to
526 analyze and non-trivial expressions could be expensive to inline. */
527 if((current_block->parent || (constant && r_trivial)) && var.interface.empty())
529 ExpressionInfo &info = expressions[&var];
530 /* Assume variables declared in an iteration initialization statement
531 will have their values change throughout the iteration. */
532 info.expression = (iteration_init ? 0 : var.init_expression.get());
533 info.assign_scope = current_block;
534 info.trivial = r_trivial;
538 void ExpressionInliner::visit(Iteration &iter)
540 SetForScope<Block *> set_block(current_block, &iter.body);
541 if(iter.init_statement)
543 SetFlag set_init(iteration_init);
544 iter.init_statement->visit(*this);
547 SetForScope<Block *> set_body(iteration_body, &iter.body);
549 visit(iter.condition);
550 iter.body.visit(*this);
551 if(iter.loop_expression)
552 visit(iter.loop_expression);
556 BasicTypeDeclaration::Kind ConstantFolder::get_value_kind(const Variant &value)
558 if(value.check_type<bool>())
559 return BasicTypeDeclaration::BOOL;
560 else if(value.check_type<int>())
561 return BasicTypeDeclaration::INT;
562 else if(value.check_type<float>())
563 return BasicTypeDeclaration::FLOAT;
565 return BasicTypeDeclaration::VOID;
569 T ConstantFolder::evaluate_logical(char oper, T left, T right)
573 case '&': return left&right;
574 case '|': return left|right;
575 case '^': return left^right;
581 bool ConstantFolder::evaluate_relation(const char *oper, T left, T right)
583 switch(oper[0]|oper[1])
585 case '<': return left<right;
586 case '<'|'=': return left<=right;
587 case '>': return left>right;
588 case '>'|'=': return left>=right;
589 default: return false;
594 T ConstantFolder::evaluate_arithmetic(char oper, T left, T right)
598 case '+': return left+right;
599 case '-': return left-right;
600 case '*': return left*right;
601 case '/': return left/right;
606 void ConstantFolder::set_result(const Variant &value, bool literal)
608 r_constant_value = value;
613 void ConstantFolder::visit(RefPtr<Expression> &expr)
615 r_constant_value = Variant();
618 r_uses_iter_var = false;
620 /* Don't replace literals since they'd only be replaced with an identical
621 literal. Also skip anything that uses an iteration variable, but pass on
622 the result so the Iteration visiting function can handle it. */
623 if(!r_constant || r_literal || r_uses_iter_var)
626 BasicTypeDeclaration::Kind kind = get_value_kind(r_constant_value);
627 if(kind==BasicTypeDeclaration::VOID)
633 RefPtr<Literal> literal = new Literal;
634 if(kind==BasicTypeDeclaration::BOOL)
635 literal->token = (r_constant_value.value<bool>() ? "true" : "false");
636 else if(kind==BasicTypeDeclaration::INT)
637 literal->token = lexical_cast<string>(r_constant_value.value<int>());
638 else if(kind==BasicTypeDeclaration::FLOAT)
639 literal->token = lexical_cast<string>(r_constant_value.value<float>());
640 literal->value = r_constant_value;
644 void ConstantFolder::visit(Literal &literal)
646 set_result(literal.value, true);
649 void ConstantFolder::visit(VariableReference &var)
651 /* If an iteration variable is initialized with a constant value, return
652 that value here for the purpose of evaluating the loop condition for the
654 if(var.declaration==iteration_var)
656 set_result(iter_init_value);
657 r_uses_iter_var = true;
661 void ConstantFolder::visit(MemberAccess &memacc)
663 TraversingVisitor::visit(memacc);
667 void ConstantFolder::visit(Swizzle &swizzle)
669 TraversingVisitor::visit(swizzle);
673 void ConstantFolder::visit(UnaryExpression &unary)
675 TraversingVisitor::visit(unary);
676 bool can_fold = r_constant;
681 BasicTypeDeclaration::Kind kind = get_value_kind(r_constant_value);
683 char oper = unary.oper->token[0];
684 char oper2 = unary.oper->token[1];
687 if(kind==BasicTypeDeclaration::BOOL)
688 set_result(!r_constant_value.value<bool>());
692 if(kind==BasicTypeDeclaration::INT)
693 set_result(~r_constant_value.value<int>());
695 else if(oper=='-' && !oper2)
697 if(kind==BasicTypeDeclaration::INT)
698 set_result(-r_constant_value.value<int>());
699 else if(kind==BasicTypeDeclaration::FLOAT)
700 set_result(-r_constant_value.value<float>());
704 void ConstantFolder::visit(BinaryExpression &binary)
707 bool left_constant = r_constant;
708 bool left_iter_var = r_uses_iter_var;
709 Variant left_value = r_constant_value;
712 r_uses_iter_var = true;
714 bool can_fold = (left_constant && r_constant);
719 BasicTypeDeclaration::Kind left_kind = get_value_kind(left_value);
720 BasicTypeDeclaration::Kind right_kind = get_value_kind(r_constant_value);
721 // Currently only expressions with both sides of equal types are handled.
722 if(left_kind!=right_kind)
725 char oper = binary.oper->token[0];
726 char oper2 = binary.oper->token[1];
727 if(oper=='&' || oper=='|' || oper=='^')
729 if(oper2==oper && left_kind==BasicTypeDeclaration::BOOL)
730 set_result(evaluate_logical(oper, left_value.value<bool>(), r_constant_value.value<bool>()));
731 else if(!oper2 && left_kind==BasicTypeDeclaration::INT)
732 set_result(evaluate_logical(oper, left_value.value<int>(), r_constant_value.value<int>()));
734 else if((oper=='<' || oper=='>') && oper2!=oper)
736 if(left_kind==BasicTypeDeclaration::INT)
737 set_result(evaluate_relation(binary.oper->token, left_value.value<int>(), r_constant_value.value<int>()));
738 else if(left_kind==BasicTypeDeclaration::FLOAT)
739 set_result(evaluate_relation(binary.oper->token, left_value.value<float>(), r_constant_value.value<float>()));
741 else if((oper=='=' || oper=='!') && oper2=='=')
743 if(left_kind==BasicTypeDeclaration::INT)
744 set_result((left_value.value<int>()==r_constant_value.value<int>()) == (oper=='='));
745 if(left_kind==BasicTypeDeclaration::FLOAT)
746 set_result((left_value.value<float>()==r_constant_value.value<float>()) == (oper=='='));
748 else if(oper=='+' || oper=='-' || oper=='*' || oper=='/')
750 if(left_kind==BasicTypeDeclaration::INT)
751 set_result(evaluate_arithmetic(oper, left_value.value<int>(), r_constant_value.value<int>()));
752 else if(left_kind==BasicTypeDeclaration::FLOAT)
753 set_result(evaluate_arithmetic(oper, left_value.value<float>(), r_constant_value.value<float>()));
755 else if(oper=='%' || ((oper=='<' || oper=='>') && oper2==oper))
757 if(left_kind!=BasicTypeDeclaration::INT)
761 set_result(left_value.value<int>()%r_constant_value.value<int>());
763 set_result(left_value.value<int>()<<r_constant_value.value<int>());
765 set_result(left_value.value<int>()>>r_constant_value.value<int>());
769 void ConstantFolder::visit(Assignment &assign)
771 TraversingVisitor::visit(assign);
775 void ConstantFolder::visit(TernaryExpression &ternary)
777 TraversingVisitor::visit(ternary);
781 void ConstantFolder::visit(FunctionCall &call)
783 TraversingVisitor::visit(call);
787 void ConstantFolder::visit(VariableDeclaration &var)
789 if(iteration_init && var.init_expression)
791 visit(var.init_expression);
794 /* Record the value of a constant initialization expression of an
795 iteration, so it can be used to evaluate the loop condition. */
796 iteration_var = &var;
797 iter_init_value = r_constant_value;
801 TraversingVisitor::visit(var);
804 void ConstantFolder::visit(Iteration &iter)
806 SetForScope<Block *> set_block(current_block, &iter.body);
808 /* The iteration variable is not normally inlined into expressions, so we
809 process it specially here. If the initial value causes the loop condition
810 to evaluate to false, then the expression can be folded. */
812 if(iter.init_statement)
814 SetFlag set_init(iteration_init);
815 iter.init_statement->visit(*this);
820 visit(iter.condition);
821 if(r_constant && r_constant_value.check_type<bool>() && !r_constant_value.value<bool>())
823 RefPtr<Literal> literal = new Literal;
824 literal->token = "false";
825 literal->value = r_constant_value;
826 iter.condition = literal;
831 iter.body.visit(*this);
832 if(iter.loop_expression)
833 visit(iter.loop_expression);
837 void ConstantConditionEliminator::apply(Stage &stage)
839 stage.content.visit(*this);
840 NodeRemover().apply(stage, nodes_to_remove);
843 ConstantConditionEliminator::ConstantStatus ConstantConditionEliminator::check_constant_condition(const Expression &expr)
845 if(const Literal *literal = dynamic_cast<const Literal *>(&expr))
846 if(literal->value.check_type<bool>())
847 return (literal->value.value<bool>() ? CONSTANT_TRUE : CONSTANT_FALSE);
851 void ConstantConditionEliminator::visit(Block &block)
853 SetForScope<Block *> set_block(current_block, &block);
854 for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
861 void ConstantConditionEliminator::visit(RefPtr<Expression> &expr)
863 r_ternary_result = 0;
866 expr = r_ternary_result;
867 r_ternary_result = 0;
870 void ConstantConditionEliminator::visit(TernaryExpression &ternary)
872 ConstantStatus result = check_constant_condition(*ternary.condition);
873 if(result!=NOT_CONSTANT)
874 r_ternary_result = (result==CONSTANT_TRUE ? ternary.true_expr : ternary.false_expr);
876 r_ternary_result = 0;
879 void ConstantConditionEliminator::visit(Conditional &cond)
881 ConstantStatus result = check_constant_condition(*cond.condition);
882 if(result!=NOT_CONSTANT)
884 Block &block = (result==CONSTANT_TRUE ? cond.body : cond.else_body);
885 // TODO should check variable names for conflicts. Potentially reuse InlineContentInjector?
886 current_block->body.splice(insert_point, block.body);
887 nodes_to_remove.insert(&cond);
891 TraversingVisitor::visit(cond);
894 void ConstantConditionEliminator::visit(Iteration &iter)
898 ConstantStatus result = check_constant_condition(*iter.condition);
899 if(result==CONSTANT_FALSE)
901 nodes_to_remove.insert(&iter);
906 TraversingVisitor::visit(iter);
910 bool UnusedTypeRemover::apply(Stage &stage)
912 stage.content.visit(*this);
913 NodeRemover().apply(stage, unused_nodes);
914 return !unused_nodes.empty();
917 void UnusedTypeRemover::visit(RefPtr<Expression> &expr)
919 unused_nodes.erase(expr->type);
920 TraversingVisitor::visit(expr);
923 void UnusedTypeRemover::visit(BasicTypeDeclaration &type)
926 unused_nodes.erase(type.base_type);
927 unused_nodes.insert(&type);
930 void UnusedTypeRemover::visit(ImageTypeDeclaration &type)
933 unused_nodes.erase(type.base_type);
934 unused_nodes.insert(&type);
937 void UnusedTypeRemover::visit(StructDeclaration &strct)
939 unused_nodes.insert(&strct);
940 TraversingVisitor::visit(strct);
943 void UnusedTypeRemover::visit(VariableDeclaration &var)
945 unused_nodes.erase(var.type_declaration);
946 TraversingVisitor::visit(var);
949 void UnusedTypeRemover::visit(InterfaceBlock &iface)
951 unused_nodes.erase(iface.type_declaration);
954 void UnusedTypeRemover::visit(FunctionDeclaration &func)
956 unused_nodes.erase(func.return_type_declaration);
957 TraversingVisitor::visit(func);
961 UnusedVariableRemover::UnusedVariableRemover():
965 assignment_target(false),
966 r_side_effects(false)
969 bool UnusedVariableRemover::apply(Stage &s)
972 s.content.visit(*this);
974 for(list<AssignmentInfo>::const_iterator i=assignments.begin(); i!=assignments.end(); ++i)
975 if(i->used_by.empty())
976 unused_nodes.insert(i->node);
978 for(BlockVariableMap::const_iterator i=variables.begin(); i!=variables.end(); ++i)
982 /* The last visible assignments of output variables are used by the
983 next stage or the API. */
984 for(vector<AssignmentInfo *>::const_iterator j=i->second.assignments.begin(); j!=i->second.assignments.end(); ++j)
985 unused_nodes.erase((*j)->node);
988 if(!i->second.output && !i->second.referenced)
990 // Don't remove variables from inside interface blocks.
991 if(!i->second.interface_block)
992 unused_nodes.insert(i->first);
994 else if(i->second.interface_block)
995 // Interface blocks are kept if even one member is used.
996 unused_nodes.erase(i->second.interface_block);
999 NodeRemover().apply(s, unused_nodes);
1001 return !unused_nodes.empty();
1004 void UnusedVariableRemover::referenced(const Assignment::Target &target, Node &node)
1006 VariableInfo &var_info = variables[target.declaration];
1007 var_info.referenced = true;
1008 if(!assignment_target)
1010 for(vector<AssignmentInfo *>::const_iterator i=var_info.assignments.begin(); i!=var_info.assignments.end(); ++i)
1011 (*i)->used_by.push_back(&node);
1015 void UnusedVariableRemover::visit(VariableReference &var)
1017 referenced(var.declaration, var);
1020 void UnusedVariableRemover::visit(InterfaceBlockReference &iface)
1022 referenced(iface.declaration, iface);
1025 void UnusedVariableRemover::visit(UnaryExpression &unary)
1027 TraversingVisitor::visit(unary);
1028 if(unary.oper->token[1]=='+' || unary.oper->token[1]=='-')
1029 r_side_effects = true;
1032 void UnusedVariableRemover::visit(BinaryExpression &binary)
1034 if(binary.oper->token[0]=='[')
1036 binary.left->visit(*this);
1037 SetFlag set(assignment_target, false);
1038 binary.right->visit(*this);
1041 TraversingVisitor::visit(binary);
1044 void UnusedVariableRemover::visit(Assignment &assign)
1047 SetFlag set(assignment_target, (assign.oper->token[0]=='='));
1048 assign.left->visit(*this);
1050 assign.right->visit(*this);
1051 r_assignment = &assign;
1052 r_side_effects = true;
1055 void UnusedVariableRemover::visit(FunctionCall &call)
1057 TraversingVisitor::visit(call);
1058 /* Treat function calls as having side effects so expression statements
1059 consisting of nothing but a function call won't be optimized away. */
1060 r_side_effects = true;
1062 if(stage->type==Stage::GEOMETRY && call.name=="EmitVertex")
1064 for(map<Statement *, VariableInfo>::const_iterator i=variables.begin(); i!=variables.end(); ++i)
1065 if(i->second.output)
1066 referenced(i->first, call);
1070 void UnusedVariableRemover::record_assignment(const Assignment::Target &target, Node &node)
1072 assignments.push_back(AssignmentInfo());
1073 AssignmentInfo &assign_info = assignments.back();
1074 assign_info.node = &node;
1075 assign_info.target = target;
1077 /* An assignment to the target hides any assignments to the same target or
1079 VariableInfo &var_info = variables[target.declaration];
1080 for(unsigned i=0; i<var_info.assignments.size(); ++i)
1082 const Assignment::Target &t = var_info.assignments[i]->target;
1084 bool subfield = (t.chain_len>=target.chain_len);
1085 for(unsigned j=0; (subfield && j<target.chain_len); ++j)
1086 subfield = (t.chain[j]==target.chain[j]);
1089 var_info.assignments.erase(var_info.assignments.begin()+i);
1094 var_info.assignments.push_back(&assign_info);
1097 void UnusedVariableRemover::visit(ExpressionStatement &expr)
1100 r_side_effects = false;
1101 TraversingVisitor::visit(expr);
1102 if(r_assignment && r_assignment->target.declaration)
1103 record_assignment(r_assignment->target, expr);
1105 unused_nodes.insert(&expr);
1108 void UnusedVariableRemover::visit(VariableDeclaration &var)
1110 VariableInfo &var_info = variables[&var];
1111 var_info.interface_block = interface_block;
1113 /* Mark variables as output if they're used by the next stage or the
1116 var_info.output = (interface_block->interface=="out" && (interface_block->linked_block || !interface_block->block_name.compare(0, 3, "gl_")));
1118 var_info.output = (var.interface=="out" && (stage->type==Stage::FRAGMENT || var.linked_declaration || !var.name.compare(0, 3, "gl_")));
1120 if(var.init_expression)
1122 var_info.initialized = true;
1123 record_assignment(&var, *var.init_expression);
1125 TraversingVisitor::visit(var);
1128 void UnusedVariableRemover::visit(InterfaceBlock &iface)
1130 VariableInfo &var_info = variables[&iface];
1131 var_info.output = (iface.interface=="out" && (iface.linked_block || !iface.block_name.compare(0, 3, "gl_")));
1134 void UnusedVariableRemover::merge_variables(const BlockVariableMap &other_vars)
1136 for(BlockVariableMap::const_iterator i=other_vars.begin(); i!=other_vars.end(); ++i)
1138 BlockVariableMap::iterator j = variables.find(i->first);
1139 if(j!=variables.end())
1141 /* The merged blocks started as copies of each other so any common
1142 assignments must be in the beginning. */
1144 for(; (k<i->second.assignments.size() && k<j->second.assignments.size()); ++k)
1145 if(i->second.assignments[k]!=j->second.assignments[k])
1148 // Remaining assignments are unique to each block; merge them.
1149 j->second.assignments.insert(j->second.assignments.end(), i->second.assignments.begin()+k, i->second.assignments.end());
1150 j->second.referenced |= i->second.referenced;
1153 variables.insert(*i);
1157 void UnusedVariableRemover::visit(FunctionDeclaration &func)
1159 if(func.body.body.empty())
1162 BlockVariableMap saved_vars = variables;
1163 // Assignments from other functions should not be visible.
1164 for(BlockVariableMap::iterator i=variables.begin(); i!=variables.end(); ++i)
1165 i->second.assignments.resize(i->second.initialized);
1166 TraversingVisitor::visit(func);
1167 swap(variables, saved_vars);
1168 merge_variables(saved_vars);
1170 /* Always treat function parameters as referenced. Removing unused
1171 parameters is not currently supported. */
1172 for(NodeArray<VariableDeclaration>::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
1174 BlockVariableMap::iterator j = variables.find(i->get());
1175 if(j!=variables.end())
1176 j->second.referenced = true;
1180 void UnusedVariableRemover::visit(Conditional &cond)
1182 cond.condition->visit(*this);
1183 BlockVariableMap saved_vars = variables;
1184 cond.body.visit(*this);
1185 swap(saved_vars, variables);
1186 cond.else_body.visit(*this);
1188 /* Visible assignments after the conditional is the union of those visible
1189 at the end of the if and else blocks. If there was no else block, then it's
1190 the union of the if block and the state before it. */
1191 merge_variables(saved_vars);
1194 void UnusedVariableRemover::visit(Iteration &iter)
1196 BlockVariableMap saved_vars = variables;
1197 TraversingVisitor::visit(iter);
1199 /* Merge assignments from the iteration, without clearing previous state.
1200 Further analysis is needed to determine which parts of the iteration body
1201 are always executed, if any. */
1202 merge_variables(saved_vars);
1206 bool UnusedFunctionRemover::apply(Stage &stage)
1208 stage.content.visit(*this);
1209 NodeRemover().apply(stage, unused_nodes);
1210 return !unused_nodes.empty();
1213 void UnusedFunctionRemover::visit(FunctionCall &call)
1215 TraversingVisitor::visit(call);
1217 unused_nodes.erase(call.declaration);
1218 if(call.declaration && call.declaration->definition!=call.declaration)
1219 used_definitions.insert(call.declaration->definition);
1222 void UnusedFunctionRemover::visit(FunctionDeclaration &func)
1224 TraversingVisitor::visit(func);
1226 if((func.name!="main" || func.body.body.empty()) && !used_definitions.count(&func))
1227 unused_nodes.insert(&func);