|A question about Dominators firstname.lastname@example.org (Robert Sherry) (2001-12-15)|
|Re:A question about Dominators email@example.com (kvinay) (2001-12-20)|
|Re: A question about Dominators firstname.lastname@example.org (2001-12-20)|
|Re: A question about Dominators Martin.Ward@durham.ac.uk (2001-12-20)|
|Re: A question about Dominators email@example.com (2001-12-20)|
|Re: A question about Dominators firstname.lastname@example.org (Jeremy Wright) (2001-12-20)|
|Date:||20 Dec 2001 00:33:56 -0500|
|Organization:||AOL Bertelsmann Online GmbH & Co. KG http://www.germany.aol.com|
|Posted-Date:||20 Dec 2001 00:33:56 EST|
"Robert Sherry" <email@example.com>schreibt:
>The basic idea of the first approach is that node a
>dominates node b if and only if a=b or a is the unique immediate predecessor
>of b or b has more then one immediate predecessor and for all immediate
>predecessors c of b, c is not equal to a and a dominates c.
IMO it's a matter of taste/convention, whether a node dominates itself
(a=b). But I definitely see no reason, why the dominator cannot be
one of multiple immediate predecessors.
In a graph with the edges (a,b), (a,c), (b,c) node a dominates both
nodes b and c.
So the idea should read:
Node a dominates node b if a=b, or for all immediate predecessors c of b, a
Now the case a=b also makes sense, since when node a is an immediate
predecessor of b, then node a dominates itself (as predecessor c of b). It's
not required that a<>c, and a single predecessor is only a special case of
BTW, do you have an equivalent definition or idea for post-dominators?
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