Support for GEP in init values & pointer subtraction in alias analysis #568
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This PR fixes the following two problems.
(1) #567 added support for parsing GEPs in initializers of globals, however, our
GEPToAdditiondidn't lower those GEPs to additions which caused exceptions during encoding (cause GEPs were not encodable).(2) When dealing with code that uses
container_of-magic, the IR ends up having pointer subtractions (e.g.ptr - 12).Our alias analysis wrongly handled those (it was not just imprecise but also incorrect!).
I added handling for subtraction. @xeren Can you check that my simple fix makes sense?