[llvm] [SandboxVec] SandboxVectorizerIR Boilerplate (PR #189515)

[Jorge Gorbe Moya via llvm-commits]

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@@ -5,20 +5,43 @@
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
+//
+// NOTE: Please #define DEF_DISABLE_AUTO_UNDEF before including more than one
+//       .def file to stop the .def file from automatically undefying macros.
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slackito wrote:

Typo: undefing?

https://github.com/llvm/llvm-project/pull/189515