[all-commits] [llvm/llvm-project] 3883e2: [flang][OpenMP] Add semantic check for target nesting

[PeixinQiao via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 3883e266f4abd33e19a7c656dde19b6f5c7fc134
      https://github.com/llvm/llvm-project/commit/3883e266f4abd33e19a7c656dde19b6f5c7fc134
  Author: PeixinQiao <qiaopeixin at huawei.com>
  Date:   2021-08-18 (Wed, 18 Aug 2021)

  Changed paths:
    M flang/lib/Semantics/check-omp-structure.cpp
    M flang/lib/Semantics/check-omp-structure.h
    A flang/test/Semantics/omp-nested-target.f90

  Log Message:
  -----------
  [flang][OpenMP] Add semantic check for target nesting

This patch implements the following check for TARGET construct:
```
OpenMP Version 5.0 Target construct restriction: If a target update,
target data, target enter data, or target exit data construct is
encountered during execution of a target region, the behavior is
unspecified.
```

Also add one test case for the check.

Reviewed By: kiranchandramohan, clementval

Differential Revision: https://reviews.llvm.org/D106165