The partially-ordered state spaces of symbolic trajectory evaluation
(STE and GSTE) provide a built-in data abstraction mechanism that can
be very effective in reducing verification complexity. The mechanism
works through clever encodings of individual verification formulas,
which make them easier to prove but which may also make it impossible
to compose them together to derive more comprehensive properties. This
talk presents a practical algorithm for transforming directly-stated
formulas into this encoded form, together with a characterisation of
its soundness conditions. These results allow properties to be both
efficiently verified in abstracted form and still composed to derive
larger properties.
The talk places this work in the context of reasoning about
microarchitectural algorithms in processor designs, one of its main
motivations. We are particularly interested in high-level models that
express algorithms involving embedded memories, because the
abstraction transformation is especially well suited to verifying
operations on these.
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