[llvm] [SandboxVectorizer] Use sbvec-passes flag to create a pipeline of Region passes after BottomUpVec. (PR #111223)

[via llvm-commits]

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@@ -0,0 +1,20 @@
+//===- PassRegistry.def - Registry of passes --------------------*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is used as the registry of sub-passes that are part of the
+// SandboxVectorizer pass.
+//
+//===----------------------------------------------------------------------===//
+
+// NOTE: NO INCLUDE GUARD DESIRED!
+
+#ifndef REGION_PASS
+#define REGION_PASS(NAME, CREATE_PASS)
+#endif
+
+REGION_PASS("null", NullPass())
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vporpo wrote:

Also why use `NullPass()` and not just the class name `NullPass` in `REGION_PASS("null", NullPass())`. Isn't the class name easier to work with?

https://github.com/llvm/llvm-project/pull/111223