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

[via llvm-commits]

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@@ -280,6 +280,7 @@ int omp_get_initial_device(void);
 void *omp_target_alloc(size_t Size, int DeviceNum);
 void omp_target_free(void *DevicePtr, int DeviceNum);
 int omp_target_is_present(const void *Ptr, int DeviceNum);
+int omp_target_is_accessible(const void *Ptr, size_t Size, int DeviceNum);
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jprotze wrote:

Entries in kmp_ftn_entry.h and kmp_ftn_os.h are missing. Check `FTN_TARGET_IS_PRESENT` for reference.

@mjklemm at the moment, I cannot successfully compile a program using any of the device memory information routines without `-fopenmp-targets` flag. Is this a bug or feature?

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