[flang-commits] [flang] [flang][OpenMP] Support custom mappers in target update to/from clauses (PR #169673)

[Krish Gupta via flang-commits]

KrxGu wrote:

@TIFitis @kparzysz.
Thanks for the review! I've addressed all the feedback:

1. Extracted `ResolveMapperModifier` helper to eliminate code duplication
2. Simplified the semantics test 
3. Moved the lowering test to `declare-mapper.f90`

Also fixed the test expectations - they were using incorrect mangled names for program-scoped mappers. 

CI all green, Good To Merge!!

https://github.com/llvm/llvm-project/pull/169673