[llvm] [Offload] Add MPI Proxy Plugin (PR #114574)

[Hervé Yviquel via llvm-commits]

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@@ -194,8 +194,10 @@ set (LIBOMPTARGET_ALL_TARGETS "${LIBOMPTARGET_ALL_TARGETS} powerpc64-ibm-linux-g
 set (LIBOMPTARGET_ALL_TARGETS "${LIBOMPTARGET_ALL_TARGETS} powerpc64-ibm-linux-gnu-LTO")
 set (LIBOMPTARGET_ALL_TARGETS "${LIBOMPTARGET_ALL_TARGETS} x86_64-unknown-linux-gnu")
 set (LIBOMPTARGET_ALL_TARGETS "${LIBOMPTARGET_ALL_TARGETS} x86_64-unknown-linux-gnu-LTO")
+set (LIBOMPTARGET_ALL_TARGETS "${LIBOMPTARGET_ALL_TARGETS} x86_64-unknown-linux-gnu-mpi")
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hyviquel wrote:

MPI is only used for the communication between the host and the devices but the target region can be lowered either to x86_64 and executed on remote CPUs or lowered to nvptx64 and executed on remote GPUs.

https://github.com/llvm/llvm-project/pull/114574