[llvm] [AMDGPU][NewInsertWaitcnts] Boilerplate for the new wait insertion pass (PR #226335)

[Pierre van Houtryve via llvm-commits]

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@@ -0,0 +1,78 @@
+//===- AMDGPUNewInsertWaitcnts.cpp - Wait Instruction Insertion Pass ------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// A wait insertion pass for AMDGPU.
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Pierre-vh wrote:

Add a bit more content to explain this is a work in progress to be an eventual replacement of SIInsertWaitcnt.

https://github.com/llvm/llvm-project/pull/226335