Improve the SMT generated for array lookups with symbolic indices #378
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What4 attempts to simplify array lookups of values with concrete indices. In cases where the index to look up in symbolic, that fails and it instead generates a huge mux over all possible indexes, which is very expensive and counterproductive. This commit removes the special handling of symbolic indices, allowing the generated SMT to fall back on just issuing an SMT array lookup. Fixes #371
andreistefanescu
suggested changes
Dec 16, 2019
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@travitch let's add a test, to prevent accidentally reintroducing the muxing
robdockins
approved these changes
Dec 18, 2019
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What4 attempts to simplify array lookups of values with concrete indices. In
cases where the index to look up in symbolic, that fails and it instead
generates a huge mux over all possible indexes, which is very expensive and
counterproductive.
This commit removes the special handling of symbolic indices, allowing the
generated SMT to fall back on just issuing an SMT array lookup.
Fixes #371