2fe8327406
This patch replaces (llvm::|)Optional< with std::optional<. I'll post a separate patch to clean up the "using" declarations, #include "llvm/ADT/Optional.h", etc. This is part of an effort to migrate from llvm::Optional to std::optional: https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716