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

[Joseph Huber via llvm-commits]

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@@ -0,0 +1,110 @@
+##===----------------------------------------------------------------------===##
+#
+# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+#
+##===----------------------------------------------------------------------===##
+#
+# Build a plugin for a MPI machine if available.
+#
+##===----------------------------------------------------------------------===##
+if (NOT(CMAKE_SYSTEM_PROCESSOR MATCHES "(x86_64)|(ppc64le)$" AND CMAKE_SYSTEM_NAME MATCHES "Linux"))
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jhuber6 wrote:

There's no official LLVM style on CMake I don't think, but I prefer `if()` with no spaces.

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