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Commit
35676a4f9a536a2aab768af63ddbb15bc722d7f9
by nikita.ppv**[InstCombine] Generalize icmp handling in isKnownNonZero()

The dominating condition handling in isKnownNonZero() currently

only takes into account conditions of the form "x != 0" or "x == 0".

However, there are plenty of other conditions that imply non-zero,

a common one being "x s> 0".

Peculiarly, the handling for assumes was already dealing with more

general non-zero-ness conditions, so this just reuses the same

logic for the dominating condition case.