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

[Vasileios Porpodas via llvm-commits]

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+//===- AMDGPUEventTracking.h ------------------------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+/// \file Tracks a per-InstCounterType event timeline which preserves
+/// information about previously encountered MachineInstr and HWEvents.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIB_TARGET_AMDGPU_UTILS_AMDGPUEVENTTRACKING_H
+#define LLVM_LIB_TARGET_AMDGPU_UTILS_AMDGPUEVENTTRACKING_H
+
+#include "AMDGPUHWEvents.h"
+#include "AMDGPUWaitcntUtils.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Twine.h"
+#include <memory>
+
+namespace llvm {
+class raw_ostream;
+class MachineBasicBlock;
+class MachineOperand;
+class MachineFunction;
+
+namespace AMDGPU {
+namespace eventtracking {
+
+class EventTrackingContext;
+class EventTracker;
+
+/// FIXME: Make this a generic util?
+struct CounterInfo {
+  constexpr CounterInfo(InstCounterType T, HWEvents Events, unsigned Limit)
+      : CounterT(T), Events(Events), Limit(Limit) {}
+
+  /// Type of counter this is.
+  /// This must match the index in the container, e.g. CounterT=2 must be at
+  /// index 2.
+  InstCounterType CounterT;
+  /// HWEvents for this counter.
+  HWEvents Events;
+  /// Hardware limit for this counter.
+  unsigned Limit;
+};
+
+/// Represents entries in the \ref EventTracker.
+///
+/// Records are all uniquely identified by a \ref DynamicInstanceID. For each
+/// unique \ref DynamicInstanceID value, all \ref EventTrackerRecord that use
+/// that ID should have the same MI and Kind. This is enforced by exposing these
+/// as read-only, and making the constructor assign a new \ref DynamicInstanceID
+/// every time.
+///
+/// Only the score can change as it may be unique to each instance
+/// of \ref EventTracker that carry it.
+class EventTrackerRecord {
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vporpo wrote:

This is the entry within CounterData, so shouldn't this be named accordingly, like CounterRecord ?

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