[llvm] [IR] Fix canReplacePointersIfEqual to properly validate vector pointers (PR #174142)

[Nikita Popov via llvm-commits]

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@@ -842,12 +842,56 @@ static bool isPointerAlwaysReplaceable(const Value *From, const Value *To,
          getUnderlyingObjectAggressive(To);
 }
 
+// Return true if all element of vector `To` is AlwaysReplaceable
+static bool CheckVectorPtrAlwaysReplaceable(const Value *From, const Value *To,
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nikic wrote:

I don't think this is worth the bother. I'd just add a `isPointerTy()` check before calling isDereferenceablePointer().

https://github.com/llvm/llvm-project/pull/174142