[clang] [CIR] Upstream TryCallOp (PR #165303)

[Andy Kaylor via cfe-commits]

andykaylor wrote:

> Note for the future @andykaylor @bcardosolopes I believe we should keep apart 2 versions: `cir.scf.try_call` with regions (sctructured control flow) and `cir.try_call` with blocks as destinations. Might be the similar issue for other operations, we should try to separate structured and unstructured paradigms.

@xlauko In general, I agree with what you're saying, though in this case there is no direct structured equivalent. Before flattening the `cir.call` just appears inside a try block and has no specified control flow of its own.

https://github.com/llvm/llvm-project/pull/165303