[llvm] [Offload] Add MPI Plugin (PR #90890)

[Joseph Huber via llvm-commits]

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@@ -108,3 +108,21 @@ if(LIBOMPTARGET_AMDGPU_ARCH)
 endif()
 
 set(OPENMP_PTHREAD_LIB ${LLVM_PTHREAD_LIB})
+
+################################################################################
+# Looking for MPI...
+################################################################################
+find_package(MPI QUIET)
+
+set(LIBOMPTARGET_DEP_MPI_FOUND ${MPI_CXX_FOUND})
+set(LIBOMPTARGET_DEP_MPI_LIBRARIES ${MPI_CXX_LIBRARIES})
+set(LIBOMPTARGET_DEP_MPI_INCLUDE_DIRS ${MPI_CXX_INCLUDE_DIRS})
+set(LIBOMPTARGET_DEP_MPI_COMPILE_FLAGS ${MPI_CXX_COMPILE_FLAGS})
+set(LIBOMPTARGET_DEP_MPI_LINK_FLAGS ${MPI_CXX_LINK_FLAGS})
+
+mark_as_advanced(
+  LIBOMPTARGET_DEP_MPI_FOUND
+  LIBOMPTARGET_DEP_MPI_LIBRARIES
+  LIBOMPTARGET_DEP_MPI_INCLUDE_DIRS
+  LIBOMPTARGET_DEP_MPI_COMPILE_FLAGS
+  LIBOMPTARGET_DEP_MPI_LINK_FLAGS)
----------------
jhuber6 wrote:

The only consumer of these dependencies is the new `mpi` plugin. I would just move it there. I'm probably going to delete this entire file at some point and move it closer to the use.

https://github.com/llvm/llvm-project/pull/90890