+void ProgramCompiler::UnusedVariableLocator::visit(FunctionDeclaration &func)
+{
+ assignments.push_back(BlockAssignmentMap());
+
+ for(vector<NodePtr<VariableDeclaration> >::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
+ (*i)->visit(*this);
+ func.body.visit(*this);
+
+ BlockAssignmentMap &block_assignments = assignments.back();
+ for(map<string, VariableDeclaration *>::iterator i=func.body.variables.begin(); i!=func.body.variables.end(); ++i)
+ block_assignments.erase(i->second);
+ for(BlockAssignmentMap::iterator i=block_assignments.begin(); i!=block_assignments.end(); ++i)
+ {
+ if(i->first->interface=="out" && stage->type!=FRAGMENT && !i->first->linked_declaration)
+ continue;
+
+ for(vector<Node *>::iterator j=i->second.nodes.begin(); j!=i->second.nodes.end(); ++j)
+ unused_nodes.erase(*j);
+ }
+
+ assignments.pop_back();
+}
+
+void ProgramCompiler::UnusedVariableLocator::merge_down_assignments()
+{
+ BlockAssignmentMap &parent_assignments = assignments[assignments.size()-2];
+ BlockAssignmentMap &block_assignments = assignments.back();
+ for(BlockAssignmentMap::iterator i=block_assignments.begin(); i!=block_assignments.end(); ++i)
+ {
+ BlockAssignmentMap::iterator j = parent_assignments.find(i->first);
+ if(j==parent_assignments.end())
+ parent_assignments.insert(*i);
+ else if(i->second.self_referencing || i->second.conditional)
+ {
+ j->second.nodes.insert(j->second.nodes.end(), i->second.nodes.begin(), i->second.nodes.end());
+ j->second.conditional |= i->second.conditional;
+ j->second.self_referencing |= i->second.self_referencing;
+ }
+ else
+ j->second = i->second;
+ }
+ assignments.pop_back();
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(Conditional &cond)
+{
+ cond.condition->visit(*this);
+ assignments.push_back(BlockAssignmentMap());
+ cond.body.visit(*this);
+
+ BlockAssignmentMap if_assignments;
+ swap(assignments.back(), if_assignments);
+ cond.else_body.visit(*this);
+
+ BlockAssignmentMap &else_assignments = assignments.back();
+ for(BlockAssignmentMap::iterator i=else_assignments.begin(); i!=else_assignments.end(); ++i)
+ {
+ BlockAssignmentMap::iterator j = if_assignments.find(i->first);
+ if(j!=if_assignments.end())
+ {
+ i->second.nodes.insert(i->second.nodes.end(), j->second.nodes.begin(), j->second.nodes.end());
+ i->second.conditional |= j->second.conditional;
+ i->second.self_referencing |= j->second.self_referencing;
+ if_assignments.erase(j);
+ }
+ else
+ i->second.conditional = true;
+ }
+
+ for(BlockAssignmentMap::iterator i=if_assignments.begin(); i!=if_assignments.end(); ++i)
+ {
+ i->second.conditional = true;
+ else_assignments.insert(*i);
+ }
+
+ merge_down_assignments();
+}
+
+void ProgramCompiler::UnusedVariableLocator::visit(Iteration &iter)
+{
+ assignments.push_back(BlockAssignmentMap());
+ TraversingVisitor::visit(iter);
+ merge_down_assignments();
+}
+