+
+ExpressionInliner::ExpressionInliner():
+ r_ref_info(0),
+ r_any_inlined(false),
+ r_trivial(false),
+ mutating(false),
+ iteration_init(false),
+ iteration_body(0),
+ r_oper(0)
+{ }
+
+bool ExpressionInliner::apply(Stage &s)
+{
+ s.content.visit(*this);
+ return r_any_inlined;
+}
+
+void ExpressionInliner::inline_expression(Expression &expr, RefPtr<Expression> &ptr)
+{
+ ptr = expr.clone();
+ r_any_inlined = true;
+}
+
+void ExpressionInliner::visit(Block &block)
+{
+ TraversingVisitor::visit(block);
+
+ for(map<string, VariableDeclaration *>::iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
+ {
+ map<Assignment::Target, ExpressionInfo>::iterator j = expressions.lower_bound(i->second);
+ for(; (j!=expressions.end() && j->first.declaration==i->second); )
+ {
+ if(j->second.expression && j->second.inline_point)
+ inline_expression(*j->second.expression, *j->second.inline_point);
+
+ expressions.erase(j++);
+ }
+ }
+
+ /* Expressions assigned in this block may depend on local variables of the
+ block. If this is a conditionally executed block, the assignments might not
+ always happen. Mark the expressions as not available to any outer blocks. */
+ for(map<Assignment::Target, ExpressionInfo>::iterator i=expressions.begin(); i!=expressions.end(); ++i)
+ if(i->second.assign_scope==&block)
+ i->second.available = false;
+}
+
+void ExpressionInliner::visit(RefPtr<Expression> &expr)
+{
+ r_ref_info = 0;
+ expr->visit(*this);
+ if(r_ref_info && r_ref_info->expression && r_ref_info->available)
+ {
+ if(iteration_body && !r_ref_info->trivial)
+ {
+ /* Don't inline non-trivial expressions which were assigned outside
+ an iteration statement. The iteration may run multiple times, which
+ would cause the expression to also be evaluated multiple times. */
+ Block *i = r_ref_info->assign_scope;
+ for(; (i && i!=iteration_body); i=i->parent) ;
+ if(!i)
+ return;
+ }
+
+ if(r_ref_info->trivial)
+ inline_expression(*r_ref_info->expression, expr);
+ else
+ /* Record the inline point for a non-trivial expression but don't
+ inline it yet. It might turn out it shouldn't be inlined after all. */
+ r_ref_info->inline_point = &expr;
+ }
+ r_oper = expr->oper;
+ r_ref_info = 0;
+}
+
+void ExpressionInliner::visit(VariableReference &var)