[llvm] [MachineSSAUpdater][AMDGPU] Add faster version of MachineSSAUpdater class. (PR #145722)

[Valery Pykhtin via llvm-commits]

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@@ -0,0 +1,80 @@
+//===- MachineIDFSSAUpdater.h - Unstructured SSA Update Tool ----*- 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 declares the MachineIDFSSAUpdater class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_UTILS_MACHINE_SSAUPDATER2_H
+#define LLVM_TRANSFORMS_UTILS_MACHINE_SSAUPDATER2_H
+
+#include "llvm/CodeGen/MachineRegisterInfo.h"
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vpykhtin wrote:

I need to include because of `MachineRegisterInfo::VRegAttrs RegAttrs;`

https://github.com/llvm/llvm-project/pull/145722