[llvm] [AMDGPU] Add DAG mutation to improve scheduling before barriers (PR #142716)

[Juan Manuel Martinez Caamaño via llvm-commits]

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@@ -0,0 +1,100 @@
+//===--- AMDGPUBarrierLatency.cpp - AMDGPU Barrier Latency ----------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+/// \file This file contains a DAG scheduling mutation to add data dependency
+///       edges between ATOMIC_FENCE instructions and preceeding memory
+///       accesses they might be effected by the fence.
----------------
jmmartinez wrote:

Typo ?
```suggestion
///       accesses that might be affected by the fence.
```

https://github.com/llvm/llvm-project/pull/142716