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9.3.3 Comparing potentially-unorderedpoly_ints ¶

In cases where there is no definite link between twopoly_ints,we can usually make a conservatively-correct assumption. For example,the conservative assumption for alias analysis is that two referencesmight alias.

One way of checking whether [begin1,end1) might overlap[begin2,end2) using thepoly_int comparisons is:

maybe_gt (end1,begin2) && maybe_gt (end2,begin1)

and another (equivalent) way is:

!(known_le (end1,begin2) || known_le (end2,begin1))

However, in this particular example, it is better to use the range helperfunctions instead. SeeRange checks onpoly_ints.