[llvm] [Attributor] Propagate alignment through ptrmask (PR #150158)

[Shilei Tian via llvm-commits]

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@@ -5339,6 +5339,15 @@ struct AAPotentialConstantValues
     return nullptr;
   }
 
+  /// Return the minimum alignment of potential constants
+  Align getMinAlignment() const {
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shiltian wrote:

I'm not sure if that's a good idea to call it an alignment in this case. What you are doing here is essentially doing cttz (except the last shift). I'd just make `AAPotentialConstantValues` to provide this information (min trailing zeros). Also, this is assumed values.

https://github.com/llvm/llvm-project/pull/150158