Represents a data flow entry.
A property which can give us more information. Currently, it's ignored, but it would make sense to add e.g. partial flows based on PR 1421.
The start of the DFG edge. Can be a parameter (paramX, where X is a number), or base.
paramX
base
The end of the DFG edge. Can be a parameter (paramX, where X is a number), base, or the return value (returnX, where X is optional and a number indicating an index).
returnX