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

[Joseph Huber via llvm-commits]

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@@ -0,0 +1,134 @@
+# Looking for MPI...
+find_package(MPI QUIET)
+
+if(NOT(CMAKE_SYSTEM_PROCESSOR MATCHES "(x86_64)|(ppc64le)$" AND CMAKE_SYSTEM_NAME MATCHES "Linux"))
+  message(STATUS "Not building MPI offloading plugin: only support MPI in Linux x86_64 or ppc64le hosts.")
+  return()
+elseif(NOT MPI_CXX_FOUND)
+  message(STATUS "Not building MPI offloading plugin: MPI not found in system.")
+  return()
+endif()
+
+message(STATUS "Building MPI Proxy offloading plugin.")
+
+# Event System
+add_subdirectory(event_system)
+
+# MPI Plugin
+
+# Create the library and add the default arguments.
+add_target_library(omptarget.rtl.mpi MPI)
+
+target_sources(omptarget.rtl.mpi PRIVATE
+  src/rtl.cpp
+)
+
+target_link_libraries(omptarget.rtl.mpi PRIVATE
+  EventSystem
+)
+
+# Add include directories
+target_include_directories(omptarget.rtl.mpi PRIVATE
+                           ${LIBOMPTARGET_INCLUDE_DIR})
+
+# Set C++20 as the target standard for this plugin.
----------------
jhuber6 wrote:

Requiring C++20 is incompatible with the current LLVM build rules. You'll need to check if the compiler supports it and return if it's not supported.

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