def process(self):
        """
        Compute essential properties of the control flow graph.  The graph
        must have been fully populated, and its entry point specified. Other
        graph properties are computed on-demand.
        """
        if self._entry_point is None:
            raise RuntimeError("no entry point defined!")
        self._eliminate_dead_blocks()

        Compute essential properties of the control flow graph.  The graph
        must have been fully populated, and its entry point specified. Other
        graph properties are computed on-demand.
        
numba/core/controlflow.py