[clang] nonblocking/nonallocating attributes (was: nolock/noalloc) (PR #84983)

[Doug Wyatt via cfe-commits]

dougsonos wrote:

> > I think the code to do this could live in the effect set if it were under Sema (as I just described)
> 
> Seeing as the effect set is part of the type, at least the parts that are stored in the `FunctionProtoType` can’t be in Sema and have to stay in the AST library.

The idea is to have `FunctionProtoType` just vend `ArrayRef<FunctionEffect>` and `ArrayRef<FunctionEffectCondition>`, then have `FunctionEffectSet`, part of `Sema`, have a constructor that combines those from a `FunctionProtoType`.

https://github.com/llvm/llvm-project/pull/84983