Commits
John McCall committed 272a81cc4e2
Add the SuccessorMap data structure. A successor map is a somewhat targetted data structure which is designed to give you the value for the lowest key that is larger than the lookup key. This is useful when applying a transformation that isn't entirely one-to-one but where we nonetheless want to preserve the original order as much as possible, e.g. when IR-genning SILFunctions. Swift SVN r14199