[llvm] [IR][DSE] Support non-malloc functions in malloc+memset->calloc fold (PR #138299)

[Nikita Popov via llvm-commits]

================
@@ -2028,9 +2028,18 @@ struct DSEState {
     if (!InnerCallee)
       return false;
     LibFunc Func;
+    std::optional<StringRef> ZeroedVariantName = std::nullopt;
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nikic wrote:

```suggestion
    StringRef ZeroedVariantName;
```
I think it would be a bit simpler to use the empty string as the sentinel here. But I'm ok either way.

https://github.com/llvm/llvm-project/pull/138299