mutate_operator   749 src/VaryingAttributes.cpp     void mutate_operator(IRFilter *mutator, const T *op, const A op_a, Stmt *stmt) {
mutate_operator   754 src/VaryingAttributes.cpp     void mutate_operator(IRFilter *mutator, const T *op, const A op_a, const B op_b, Stmt *stmt) {
mutate_operator   760 src/VaryingAttributes.cpp     void mutate_operator(IRFilter *mutator, const T *op, const A op_a, const B op_b, const C op_c, Stmt *stmt) {