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cc99164448
Summary: MemoryDependenceAnalysis is currently cautious when the QueryInstr is an atomic load or store, but I forgot to check for atomic cmpxchg/atomicrmw. This patch is a way of fixing that, and making it less brittle (i.e. no risk that I forget another possible kind of atomic, even if the IR ends up changing in the future), by adding a fallback checking mayReadOrWriteFromMemory. Thanks to Philip Reames for finding this bug and suggesting this solution in http://reviews.llvm.org/D4845 Sadly, I don't see how to add a test for this, since the passes depending on MemoryDependenceAnalysis won't trigger for an atomic rmw anyway. Does anyone see a way for testing it? Test Plan: none possible at first sight Reviewers: jfb, reames Subscribers: llvm-commits Differential Revision: http://reviews.llvm.org/D5019 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@216940 91177308-0d34-0410-b5e6-96231b3b80d8