[Flang][OpenMP][Lower] Use clause operand structures (#86802)

This patch updates Flang lowering to use the new set of OpenMP clause
operand structures and their groupings into directive-specific sets of
clause operands.

It simplifies the passing of information from the clause processor and
the creation of operations.

The `DataSharingProcessor` is slightly modified to not hold delayed
privatization state. Instead, optional arguments are added to
`processStep1` which are only passed when delayed privatization is used.
This enables using the clause operand structure for `private` and
removes the need for the ad-hoc `DelayedPrivatizationInfo` structure.

The processing of the `schedule` clause is updated to process the
`chunk` modifier rather than requiring two separate calls to the
`ClauseProcessor`.

Lowering of a block-associated `ordered` construct is updated to emit a
TODO error if the `simd` clause is specified, since it is not currently
supported by the `ClauseProcessor` or later compilation stages.

Removed processing of `schedule` from `omp.simdloop`, as it doesn't
apply to `simd` constructs.

GitOrigin-RevId: 78eac466095c205988ef1e2380033d042a169a3b
5 files changed
tree: 3feefd614706a457c7075c0911ead24e925f793d
  1. cmake/
  2. docs/
  3. examples/
  4. include/
  5. lib/
  6. module/
  7. runtime/
  8. test/
  9. tools/
  10. unittests/
  11. .clang-format
  12. .clang-tidy
  13. .drone.star
  14. .gitignore
  15. CMakeLists.txt
  16. CODE_OWNERS.TXT
  17. LICENSE.TXT
  18. README.md
README.md

Flang

Flang is a ground-up implementation of a Fortran front end written in modern C++. It started off as the f18 project (https://github.com/flang-compiler/f18) with an aim to replace the previous flang project (https://github.com/flang-compiler/flang) and address its various deficiencies. F18 was subsequently accepted into the LLVM project and rechristened as Flang.

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To better understand Fortran as a language and the specific grammar accepted by flang, read Fortran For C Programmers and flang's specifications of the Fortran grammar and the OpenMP grammar.

Treatment of language extensions is covered in this document.

To understand the compilers handling of intrinsics, see the discussion of intrinsics.

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Consult the Getting Started with Flang for information on building and running flang.