[llvm] [SelectionDAG] Optimize unaligned load stores to realign after offset (PR #145309)

[Nikita Popov via llvm-commits]

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@@ -50,27 +50,28 @@ struct MachinePointerInfo {
 
   uint8_t StackID;
 
+  const Value *OrgV;
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nikic wrote:

We should be able to use isValidAssumeForContext with AllowEphemerals=true when determining dereferenceability.

https://github.com/llvm/llvm-project/pull/145309