[llvm-branch-commits] [flang] [llvm] [mlir] [MLIR][OpenMP] Add OpenMPToLLVMIRTranslation support for is_device_ptr (PR #169367)

[Abhinav Gaba via llvm-branch-commits]

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@@ -0,0 +1,46 @@
+! Validate that a device pointer obtained via omp_get_mapped_ptr can be used
+! inside a TARGET region with the is_device_ptr clause.
+! REQUIRES: flang, amdgcn-amd-amdhsa
+
+! RUN: %libomptarget-compile-fortran-run-and-check-generic
+
+program is_device_ptr_target
+  use iso_c_binding, only : c_ptr, c_loc
+  implicit none
+
+  interface
+    function omp_get_mapped_ptr(host_ptr, device_num)                       &
+        bind(C, name="omp_get_mapped_ptr")
+      use iso_c_binding, only : c_ptr, c_int
+      type(c_ptr) :: omp_get_mapped_ptr
+      type(c_ptr), value :: host_ptr
+      integer(c_int), value :: device_num
+    end function omp_get_mapped_ptr
+  end interface
+
+  integer, parameter :: n = 4
+  integer, parameter :: dev = 0
+  integer, target :: a(n)
+  type(c_ptr) :: dptr
+  integer :: flag
+
+  a = [2, 4, 6, 8]
+  flag = 0
+
+  !$omp target data map(tofrom: a, flag)
+    dptr = omp_get_mapped_ptr(c_loc(a), dev)
+
+    !$omp target is_device_ptr(dptr) map(tofrom: flag)
+      flag = flag + 1
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abhinavgaba wrote:

`dptr` is still not used inside the target construct. Is your goal to validate that `dptr` is correctly passed into the `target`, or just that this doesn't cause a segfault/offload-failure?

If it's the former, then one way to do it is by calling c_f_pointer inside the target region, and reading/writing the pointee via the fortran pointer. Another way is to `transfer` dptr into an `INTEGER(C_INTPTR_T)` both inside and outside the target region, print it, and CHECK that the two addresses printed are identical.

https://github.com/llvm/llvm-project/pull/169367