+ ValueMap::const_iterator i = variable_values->find(var.declaration);
+ if(i!=variable_values->end())
+ i->second->visit(*this);
+ }
+ else if(var.declaration->init_expression)
+ var.declaration->init_expression->visit(*this);
+}
+
+void ProgramCompiler::ExpressionEvaluator::visit(UnaryExpression &unary)
+{
+ result_valid = false;
+ unary.expression->visit(*this);
+ if(!result_valid)
+ return;
+
+ if(unary.oper=="!")
+ result = !result;
+ else
+ result_valid = false;
+}
+
+void ProgramCompiler::ExpressionEvaluator::visit(BinaryExpression &binary)
+{
+ result_valid = false;
+ binary.left->visit(*this);
+ if(!result_valid)
+ return;
+
+ float left_result = result;
+ result_valid = false;
+ binary.right->visit(*this);
+ if(!result_valid)
+ return;
+
+ if(binary.oper=="<")
+ result = (left_result<result);
+ else if(binary.oper=="<=")
+ result = (left_result<=result);
+ else if(binary.oper==">")
+ result = (left_result>result);
+ else if(binary.oper==">=")
+ result = (left_result>=result);
+ else if(binary.oper=="==")
+ result = (left_result==result);
+ else if(binary.oper=="!=")
+ result = (left_result!=result);
+ else if(binary.oper=="&&")
+ result = (left_result && result);
+ else if(binary.oper=="||")
+ result = (left_result || result);
+ else
+ result_valid = false;
+}
+
+
+ProgramCompiler::ConstantConditionEliminator::ConstantConditionEliminator():
+ scope_level(0)
+{ }
+
+void ProgramCompiler::ConstantConditionEliminator::visit(Block &block)
+{
+ SetForScope<unsigned> set(scope_level, scope_level+1);
+ BlockModifier::visit(block);
+
+ for(map<string, VariableDeclaration *>::const_iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
+ variable_values.erase(i->second);
+}
+
+void ProgramCompiler::ConstantConditionEliminator::visit(Assignment &assign)
+{
+ variable_values.erase(assign.target_declaration);
+}
+
+void ProgramCompiler::ConstantConditionEliminator::visit(VariableDeclaration &var)
+{
+ if(var.constant || scope_level>1)
+ variable_values[&var] = var.init_expression.get();
+}
+
+void ProgramCompiler::ConstantConditionEliminator::visit(Conditional &cond)
+{
+ ExpressionEvaluator eval(variable_values);
+ cond.condition->visit(eval);
+ if(eval.result_valid)
+ flatten_block(eval.result ? cond.body : cond.else_body);
+ else
+ TraversingVisitor::visit(cond);
+}
+
+void ProgramCompiler::ConstantConditionEliminator::visit(Iteration &iter)
+{
+ if(iter.condition)
+ {
+ ExpressionEvaluator eval;
+ iter.condition->visit(eval);
+ if(eval.result_valid && !eval.result)
+ {
+ remove_node = true;
+ return;
+ }
+ }
+
+ TraversingVisitor::visit(iter);
+}
+
+
+ProgramCompiler::UnusedVariableLocator::UnusedVariableLocator():
+ aggregate(0),
+ assignment(0),
+ assignment_target(false),
+ global_scope(true)
+{ }
+
+void ProgramCompiler::UnusedVariableLocator::apply(Stage &s)
+{
+ variables.push_back(BlockVariableMap());
+ Visitor::apply(s);
+ BlockVariableMap &global_variables = variables.back();
+ for(BlockVariableMap::iterator i=global_variables.begin(); i!=global_variables.end(); ++i)
+ {
+ if(i->first->interface=="out" && (s.type==FRAGMENT || i->first->linked_declaration || !i->first->name.compare(0, 3, "gl_")))
+ continue;
+ if(!i->second.referenced)