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Region-Based Analysis

We obtain absolute value maps describing variable values at every program point in two passes, as a region-based data-flow analysis. A bottom-up pass through the program derives the transfer function for each region, as a relative value map that describes variable values at each immediate subregion in terms of entry variable values. A subsequent top-down pass through the program propagates to each region a symbolic context, an absolute map describing actual variable values on region entry in terms of enclosing loop indices and invariants.





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