[Alias] how to use the API of getModRefInfo?

Beginners
1

hi,
We usual use isModOrRefSet(AA->getModRefInfo(A, B) to determine whether or not two instructions A and B have aliases, but what does it mean when B is specified as None?

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2

Check out the APIs starting at: llvm/AliasAnalysis.h at master · llvm-mirror/llvm · GitHub

None is the MemoryLocation.

ModRefInfo doesn’t just give the answer to “can A and B alias”, but to “can C read, write or both”
You may be looking for AA->alias().

3

Thanks @alina very much