[DependenceAnalysis] Make sure base objects are the same when comparing GEPs
The dependence analysis was returning incorrect information when using the GEPs
to compute dependences. The analysis uses the GEP indices under certain
conditions, but was doing it incorrectly when the base objects of the GEP are
aliases, but pointing to different locations in the same array.
This patch adds another check for the base objects. If the base pointer SCEVs
are not equal, then the dependence analysis should fall back on the path
that uses the whole SCEV for the dependence check. This fixes PR33567.
Differential Revision: https://reviews.llvm.org/D34702
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@307203 91177308-0d34-0410-b5e6-96231b3b80d8
Brendon Cahoon2 years ago