22426110c5
This is part of an effort to migrate from llvm::Optional to std::optional. This patch changes the way mlir-tblgen generates .inc files, and modifies tests and documentation appropriately. It is a "no compromises" patch, and doesn't leave the user with an unpleasant mix of llvm::Optional and std::optional. A non-trivial change has been made to ControlFlowInterfaces to split one constructor into two, relating to a build failure on Windows. See also: https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716 Signed-off-by: Ramkumar Ramachandra <r@artagnon.com> Differential Revision: https://reviews.llvm.org/D138934