tools/llvm-mca/Views/RetireControlUnitStatistics.cpp

   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
  17 namespace llvm {
  18 namespace mca {
  19
  20 RetireControlUnitStatistics::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
  31 void 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
  46 void RetireControlUnitStatistics::onCycleEnd() {
  47   // Update histogram
  48   RetiredPerCycle[NumRetired]++;
  49   NumRetired = 0;
  50   ++NumCycles;
  51   MaxUsedEntries = std::max(MaxUsedEntries, EntriesInUse);
  52   SumOfUsedEntries += EntriesInUse;
  53 }
  54
  55 void 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<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