[llvm] [memprof] Migrate away from PointerUnion::dyn_cast (NFC) (PR #123716)

[Nikita Popov via llvm-commits]

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@@ -3542,7 +3542,7 @@ void ModuleCallsiteContextGraph::updateAllocationCall(
 
 void IndexCallsiteContextGraph::updateAllocationCall(CallInfo &Call,
                                                      AllocationType AllocType) {
-  auto *AI = Call.call().dyn_cast<AllocInfo *>();
+  auto *AI = dyn_cast<AllocInfo *>(Call.call());
----------------
nikic wrote:

```suggestion
  auto *AI = cast<AllocInfo *>(Call.call());
```

https://github.com/llvm/llvm-project/pull/123716