``Top-Down'' Deletion Algorithm.
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- It consists of two phases:
- Remove all the analysis information that depends on the
deleted clauses.
- Restart analysis (using non-incremental algorithm).
- When we restart analysis, information that does not depend on the deleted clauses is
already present.
- ``Top-down'' deletion of clauses produces the same analysis
results as non-incremental analysis.
- Phase 2 of the algorithm cannot be worse than re-analyzing from
scratch.
- ``Top-down'' deletion algorithm is pessimistic. Everything is
deleted unless it is sure to be useful.
- In practice, it cannot be much better than re-analyzing from
scratch.
- Deleting a single clause will remove half of the analysis
information during first phase of the algorithm.
Thu Jan 18 11:22:51 MET 1996 <herme@fi.upm.es>-<webmaster@clip.dia.fi.upm.es>