Microcircuits dedicated to security in smartcards are targeted by more and more sophisticated attacks like fault attacks that combine physical disturbance and cryptanalysis. The use of simulation for circuit validation considering these attacks is limited by the time needed to compute the result of the chosen fault injections. Usually, this choice is made by the user according to his knowledge of the circuit functionality. The aim of this paper is to propose a generic and semi-automatic method to reduce the number of fault injections using types of data stored in registers (latch by latch)