code: def _make_regs_symbolic(input_state, reg_list, project):
          
          state = input_state.copy()
          # overwrite all registers
          for reg in reg_list:
              state.registers.store(reg, state.solver.BVS("sreg_" + reg + "-", project.arch.bits, explicit_name=True))
          # restore sp
          state.regs.sp = input_state.regs.sp
          # restore bp
          state.regs.bp = input_state.regs.bp
          return state
docs: converts an input state into a state with symbolic registers
          :return: the symbolic state