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Register a new userInferring Fences in a Concurrent Program Using SC proof of Correctness
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Added by
Chinmay Narayan
Publication date
2013
fields
Informatics Engineering
and research's language is
English
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Most proof systems for concurrent programs assume the underlying memory model to be sequentially consistent (SC), an assumption which does not hold for modern multicore processors. These processors, for performance reasons, implement relaxed memory models. As a result of this relaxation a program, proved correct on the SC memory model, might execute incorrectly. To ensure its correctness under relaxation, fence instructions are inserted in the code. In this paper we show that the SC proof of correctness of an algorithm, carried out in the proof system of [Sou84], identifies per-thread instruction orderings sufficient for this SC proof. Further, to correctly execute this algorithm on an underlying relaxed memory model it is sufficient to respect only these orderings by inserting fence instructions.
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