1//===--------------------- RetireControlUnitStatistics.cpp ------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8/// \file
9///
10/// This file implements the RetireControlUnitStatistics interface.
11///
12//===----------------------------------------------------------------------===//
13
14#include "Views/RetireControlUnitStatistics.h"
15#include "llvm/Support/Format.h"
16
17namespace llvm {
18namespace mca {
19
20RetireControlUnitStatistics::RetireControlUnitStatistics(const MCSchedModel &SM)
21    : NumRetired(0), NumCycles(0), EntriesInUse(0), MaxUsedEntries(0),
22      SumOfUsedEntries(0) {
23  TotalROBEntries = SM.MicroOpBufferSize;
24  if (SM.hasExtraProcessorInfo()) {
25    const MCExtraProcessorInfo &EPI = SM.getExtraProcessorInfo();
26    if (EPI.ReorderBufferSize)
27      TotalROBEntries = EPI.ReorderBufferSize;
28  }
29}
30
31void RetireControlUnitStatistics::onEvent(const HWInstructionEvent &Event) {
32  if (Event.Type == HWInstructionEvent::Dispatched) {
33    unsigned NumEntries =
34        static_cast<const HWInstructionDispatchedEvent &>(Event).MicroOpcodes;
35    EntriesInUse += NumEntries;
36  }
37
38  if (Event.Type == HWInstructionEvent::Retired) {
39    unsigned ReleasedEntries = Event.IR.getInstruction()->getDesc().NumMicroOps;
40    assert(EntriesInUse >= ReleasedEntries && "Invalid internal state!");
41    EntriesInUse -= ReleasedEntries;
42    ++NumRetired;
43  }
44}
45
46void RetireControlUnitStatistics::onCycleEnd() {
47  // Update histogram
48  RetiredPerCycle[NumRetired]++;
49  NumRetired = 0;
50  ++NumCycles;
51  MaxUsedEntries = std::max(MaxUsedEntries, EntriesInUse);
52  SumOfUsedEntries += EntriesInUse;
53}
54
55void RetireControlUnitStatistics::printView(raw_ostream &OS) const {
56  std::string Buffer;
57  raw_string_ostream TempStream(Buffer);
58  TempStream << "\n\nRetire Control Unit - "
59             << "number of cycles where we saw N instructions retired:\n";
60  TempStream << "[# retired], [# cycles]\n";
61
62  for (const std::pair<const unsigned, unsigned> &Entry : RetiredPerCycle) {
63    TempStream << " " << Entry.first;
64    if (Entry.first < 10)
65      TempStream << ",           ";
66    else
67      TempStream << ",          ";
68    TempStream << Entry.second << "  ("
69               << format("%.1f", ((double)Entry.second / NumCycles) * 100.0)
70               << "%)\n";
71  }
72
73  unsigned AvgUsage = (double)SumOfUsedEntries / NumCycles;
74  double MaxUsagePercentage = ((double)MaxUsedEntries / TotalROBEntries) * 100.0;
75  double NormalizedMaxPercentage = floor((MaxUsagePercentage * 10) + 0.5) / 10;
76  double AvgUsagePercentage = ((double)AvgUsage / TotalROBEntries) * 100.0;
77  double NormalizedAvgPercentage = floor((AvgUsagePercentage * 10) + 0.5) / 10;
78
79  TempStream << "\nTotal ROB Entries:                " << TotalROBEntries
80             << "\nMax Used ROB Entries:             " << MaxUsedEntries
81             << format("  ( %.1f%% )", NormalizedMaxPercentage)
82             << "\nAverage Used ROB Entries per cy:  " << AvgUsage
83             << format("  ( %.1f%% )\n", NormalizedAvgPercentage);
84
85  TempStream.flush();
86  OS << Buffer;
87}
88
89} // namespace mca
90} // namespace llvm
91