[llvm] [TableGen] Factor out timer code into a new `TGTimer` class (PR #111054)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,58 @@
+//===- llvm/TableGen/TGTimer.h - Class for TableGen Timer -------*- 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 defines the TableGen timer class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TABLEGEN_TGTIMER_H
+#define LLVM_TABLEGEN_TGTIMER_H
+
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Timer.h"
+
+namespace llvm {
+
+// Timer related functionality f or TableGen backends.
+class TGTimer {
+private:
+  TimerGroup *TimingGroup = nullptr;
+  Timer *LastTimer = nullptr;
+  bool BackendTimer = false; // Is last timer special backend overall timer?
+
+public:
+  TGTimer() = default;
+
+  /// Start phase timing; called if the --time-phases option is specified.
+  void startPhaseTiming() {
+    TimingGroup = new TimerGroup("TableGen", "TableGen Phase Timing");
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arsenm wrote:

unique_ptr. Destructor is missing 

https://github.com/llvm/llvm-project/pull/111054