[llvm] [OpenMP][Offload] Handle non-memberof `present/to/from` entries irrespective of order. (PR #165494)

[Deepak Eachempati via llvm-commits]

dreachem wrote:

@abhinavgaba 
> (1) would be simpler, but won't work for cases like:
> 
> ```c
>   ... map(delete: x) map(from:x)
> ```
> 
> as there is no clear "winner" between the two. So, for such cases, the compiler would likely have to do (2), which is the cleanest solution, but will take longer to implement. For EXPR comparisons, it can build-upon the `AttachPtrExprComparator` that was implemented as part of #153683, but that should probably wait for the PR to be merged to avoid conflicts.

Why wouldn't `from` just be sorted before `delete` in that case? The behavior should be "Do a `target_update from(x)` if ref count equals 1, and then delete it".



https://github.com/llvm/llvm-project/pull/165494