[llvm] [OpenMP] Adds omp_target_is_accessible routine (PR #138294)

[Krzysztof Parzyszek via llvm-commits]

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@@ -195,6 +195,49 @@ EXTERN int omp_target_is_present(const void *Ptr, int DeviceNum) {
   return Rc;
 }
 
+/// Check whether a pointer is accessible from a device.
+/// the functionality is available in OpenMP 5.1 and later
+/// OpenMP 5.1
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kparzysz wrote:

The runtime shouldn't care about the version.  The compiler can check the version, and can warn/error out when it sees a call to `omp_xyz` routine that is unavailable in that version (IIRC identifiers starting with omp_ are reserved for the implementation).

https://github.com/llvm/llvm-project/pull/138294