[llvm] [AMDGPU][NewInsertWaitcnt] Add Event Tracker (PR #226970)

[Vasileios Porpodas via llvm-commits]

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@@ -0,0 +1,477 @@
+//===- AMDGPUEventTracking.cpp ----------------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "AMDGPUEventTracking.h"
+#include "AMDGPUHWEvents.h"
+#include "AMDGPUWaitcntUtils.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Debug.h"
+#include <algorithm>
+#include <optional>
+
+#define DEBUG_TYPE "amdgpu-event-tracking"
+
+namespace llvm {
+
+/// Mimic legacy (coarse) tracking of counter state.
+static cl::opt<bool> MimicLegacyTracking("amdgpu-event-legacy-tracking",
+                                         cl::init(false));
+
+#ifndef NDEBUG
+static cl::opt<bool> EventTrackerPrintAll(
+    "amdgpu-event-tracker-print-all", cl::init(false),
+    cl::desc("When using -debug, print the full set of live events every time "
+             "an event is added or removed"));
+#endif
+
+namespace AMDGPU {
+namespace eventtracking {
+
+namespace {
+static bool greaterThan(const EventTrackerRecord &A,
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vporpo wrote:

`greaterThan` isn't very descriptive. Also why isn't this a member function?

https://github.com/llvm/llvm-project/pull/226970