Single-entry single-exit

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In mathematics graph theory, a single-entry single-exit (SESE) region in a given graph is an ordered edge pair.

For example, with the ordered edge pair, (a, b) of distinct control-flow edges a and b where:

  1. a dominates b
  2. b postdominates a
  3. Every cycle containing a also contains b and vice versa.

where a node x is said to dominate node y in a directed graph if every path from start to y includes x. A node x is said to postdominate a node y if every path from y to end includes x.

So, a and b refer to the entry and exit edge, respectively.

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References

  1. The program structure tree: computing control regions in linear time