112   return itr == X.itr;  in operator ==()
116   return itr != X.itr;  in operator !=()
120   itr.push_back(SE);  in symbol_iterator()
124   assert(!itr.empty() && "attempting to iterate on an 'end' iterator");  in operator ++()
130   assert(!itr.empty() && "attempting to dereference an 'end' iterator");  in operator *()
131   return itr.back();  in operator *()
135   const SymExpr *SE = itr.pop_back_val();  in expand()
145       itr.push_back(cast<SymbolCast>(SE)->getOperand());  in expand()
148       itr.push_back(cast<UnarySymExpr>(SE)->getOperand());  in expand()
151       itr.push_back(cast<SymIntExpr>(SE)->getLHS());  in expand()
154       itr.push_back(cast<IntSymExpr>(SE)->getRHS());  in expand()
158       itr.push_back(x->getLHS());  in expand()
159       itr.push_back(x->getRHS());  in expand()