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Inequality Constraints

The symbolic analysis described thus far can only determine equality constraints between variables. Since array analysis also benefits from knowledge of loop bounds and other control-based contextual constraints on variables (e.g., if predicates), which may contain inequalities, a separate top-down pass carries loop and predicate constraints to relevant array accesses. Equality constraints determined by the symbolic analysis are used to rephrase each predicate in loop-invariant terms, if possible. The control context is represented by a set of affine inequalities in the form discussed in Section 5.



Saman Amarasinghe
Mon Oct 2 11:00:22 PDT 1995