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1//===--------------------- TimelineView.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-exception6//7//===----------------------------------------------------------------------===//8/// \brief9///10/// This file implements the TimelineView interface.11///12//===----------------------------------------------------------------------===//13 14#include "Views/TimelineView.h"15#include <numeric>16 17namespace llvm {18namespace mca {19 20TimelineView::TimelineView(const MCSubtargetInfo &sti, MCInstPrinter &Printer,21                           llvm::ArrayRef<llvm::MCInst> S, unsigned Iterations,22                           unsigned Cycles)23    : InstructionView(sti, Printer, S), CurrentCycle(0),24      MaxCycle(Cycles == 0 ? std::numeric_limits<unsigned>::max() : Cycles),25      LastCycle(0), WaitTime(S.size()), UsedBuffer(S.size()) {26  unsigned NumInstructions = getSource().size();27  assert(Iterations && "Invalid number of iterations specified!");28  NumInstructions *= Iterations;29  Timeline.resize(NumInstructions);30  TimelineViewEntry InvalidTVEntry = {-1, 0, 0, 0, 0};31  llvm::fill(Timeline, InvalidTVEntry);32 33  WaitTimeEntry NullWTEntry = {0, 0, 0};34  llvm::fill(WaitTime, NullWTEntry);35 36  std::pair<unsigned, int> NullUsedBufferEntry = {/* Invalid resource ID*/ 0,37                                                  /* unknown buffer size */ -1};38  llvm::fill(UsedBuffer, NullUsedBufferEntry);39}40 41void TimelineView::onReservedBuffers(const InstRef &IR,42                                     ArrayRef<unsigned> Buffers) {43  if (IR.getSourceIndex() >= getSource().size())44    return;45 46  const MCSchedModel &SM = getSubTargetInfo().getSchedModel();47  std::pair<unsigned, int> BufferInfo = {0, -1};48  for (const unsigned Buffer : Buffers) {49    const MCProcResourceDesc &MCDesc = *SM.getProcResource(Buffer);50    if (!BufferInfo.first || BufferInfo.second > MCDesc.BufferSize) {51      BufferInfo.first = Buffer;52      BufferInfo.second = MCDesc.BufferSize;53    }54  }55 56  UsedBuffer[IR.getSourceIndex()] = BufferInfo;57}58 59void TimelineView::onEvent(const HWInstructionEvent &Event) {60  const unsigned Index = Event.IR.getSourceIndex();61  if (Index >= Timeline.size())62    return;63 64  switch (Event.Type) {65  case HWInstructionEvent::Retired: {66    TimelineViewEntry &TVEntry = Timeline[Index];67    if (CurrentCycle < MaxCycle)68      TVEntry.CycleRetired = CurrentCycle;69 70    // Update the WaitTime entry which corresponds to this Index.71    assert(TVEntry.CycleDispatched >= 0 && "Invalid TVEntry found!");72    unsigned CycleDispatched = static_cast<unsigned>(TVEntry.CycleDispatched);73    WaitTimeEntry &WTEntry = WaitTime[Index % getSource().size()];74    WTEntry.CyclesSpentInSchedulerQueue +=75        TVEntry.CycleIssued - CycleDispatched;76    assert(CycleDispatched <= TVEntry.CycleReady &&77           "Instruction cannot be ready if it hasn't been dispatched yet!");78    WTEntry.CyclesSpentInSQWhileReady +=79        TVEntry.CycleIssued - TVEntry.CycleReady;80    if (CurrentCycle > TVEntry.CycleExecuted) {81      WTEntry.CyclesSpentAfterWBAndBeforeRetire +=82          (CurrentCycle - 1) - TVEntry.CycleExecuted;83    }84    break;85  }86  case HWInstructionEvent::Ready:87    Timeline[Index].CycleReady = CurrentCycle;88    break;89  case HWInstructionEvent::Issued:90    Timeline[Index].CycleIssued = CurrentCycle;91    break;92  case HWInstructionEvent::Executed:93    Timeline[Index].CycleExecuted = CurrentCycle;94    break;95  case HWInstructionEvent::Dispatched:96    // There may be multiple dispatch events. Microcoded instructions that are97    // expanded into multiple uOps may require multiple dispatch cycles. Here,98    // we want to capture the first dispatch cycle.99    if (Timeline[Index].CycleDispatched == -1)100      Timeline[Index].CycleDispatched = static_cast<int>(CurrentCycle);101    break;102  default:103    return;104  }105  if (CurrentCycle < MaxCycle)106    LastCycle = std::max(LastCycle, CurrentCycle);107}108 109static raw_ostream::Colors chooseColor(unsigned CumulativeCycles,110                                       unsigned Executions, int BufferSize) {111  if (CumulativeCycles && BufferSize < 0)112    return raw_ostream::MAGENTA;113  unsigned Size = static_cast<unsigned>(BufferSize);114  if (CumulativeCycles >= Size * Executions)115    return raw_ostream::RED;116  if ((CumulativeCycles * 2) >= Size * Executions)117    return raw_ostream::YELLOW;118  return raw_ostream::SAVEDCOLOR;119}120 121static void tryChangeColor(raw_ostream &OS, unsigned Cycles,122                           unsigned Executions, int BufferSize) {123  if (!OS.has_colors())124    return;125 126  raw_ostream::Colors Color = chooseColor(Cycles, Executions, BufferSize);127  if (Color == raw_ostream::SAVEDCOLOR) {128    OS.resetColor();129    return;130  }131  OS.changeColor(Color, /* bold */ true, /* BG */ false);132}133 134void TimelineView::printWaitTimeEntry(formatted_raw_ostream &OS,135                                      const WaitTimeEntry &Entry,136                                      unsigned SourceIndex,137                                      unsigned Executions) const {138  bool PrintingTotals = SourceIndex == getSource().size();139  unsigned CumulativeExecutions = PrintingTotals ? Timeline.size() : Executions;140 141  if (!PrintingTotals)142    OS << SourceIndex << '.';143 144  OS.PadToColumn(7);145 146  double AverageTime1, AverageTime2, AverageTime3;147  AverageTime1 =148      (double)(Entry.CyclesSpentInSchedulerQueue * 10) / CumulativeExecutions;149  AverageTime2 =150      (double)(Entry.CyclesSpentInSQWhileReady * 10) / CumulativeExecutions;151  AverageTime3 = (double)(Entry.CyclesSpentAfterWBAndBeforeRetire * 10) /152                 CumulativeExecutions;153 154  OS << Executions;155  OS.PadToColumn(13);156 157  int BufferSize = PrintingTotals ? 0 : UsedBuffer[SourceIndex].second;158  if (!PrintingTotals)159    tryChangeColor(OS, Entry.CyclesSpentInSchedulerQueue, CumulativeExecutions,160                   BufferSize);161  OS << format("%.1f", floor(AverageTime1 + 0.5) / 10);162  OS.PadToColumn(20);163  if (!PrintingTotals)164    tryChangeColor(OS, Entry.CyclesSpentInSQWhileReady, CumulativeExecutions,165                   BufferSize);166  OS << format("%.1f", floor(AverageTime2 + 0.5) / 10);167  OS.PadToColumn(27);168  if (!PrintingTotals)169    tryChangeColor(OS, Entry.CyclesSpentAfterWBAndBeforeRetire,170                   CumulativeExecutions,171                   getSubTargetInfo().getSchedModel().MicroOpBufferSize);172  OS << format("%.1f", floor(AverageTime3 + 0.5) / 10);173 174  if (OS.has_colors())175    OS.resetColor();176  OS.PadToColumn(34);177}178 179void TimelineView::printAverageWaitTimes(raw_ostream &OS) const {180  std::string Header =181      "\n\nAverage Wait times (based on the timeline view):\n"182      "[0]: Executions\n"183      "[1]: Average time spent waiting in a scheduler's queue\n"184      "[2]: Average time spent waiting in a scheduler's queue while ready\n"185      "[3]: Average time elapsed from WB until retire stage\n\n"186      "      [0]    [1]    [2]    [3]\n";187  OS << Header;188  formatted_raw_ostream FOS(OS);189  unsigned Executions = Timeline.size() / getSource().size();190  unsigned IID = 0;191  for (const MCInst &Inst : getSource()) {192    printWaitTimeEntry(FOS, WaitTime[IID], IID, Executions);193    FOS << "   " << printInstructionString(Inst) << '\n';194    FOS.flush();195    ++IID;196  }197 198  // If the timeline contains more than one instruction,199  // let's also print global averages.200  if (getSource().size() != 1) {201    WaitTimeEntry TotalWaitTime = std::accumulate(202        WaitTime.begin(), WaitTime.end(), WaitTimeEntry{0, 0, 0},203        [](const WaitTimeEntry &A, const WaitTimeEntry &B) {204          return WaitTimeEntry{205              A.CyclesSpentInSchedulerQueue + B.CyclesSpentInSchedulerQueue,206              A.CyclesSpentInSQWhileReady + B.CyclesSpentInSQWhileReady,207              A.CyclesSpentAfterWBAndBeforeRetire +208                  B.CyclesSpentAfterWBAndBeforeRetire};209        });210    printWaitTimeEntry(FOS, TotalWaitTime, IID, Executions);211    FOS << "   "212        << "<total>" << '\n';213    FOS.flush();214  }215}216 217void TimelineView::printTimelineViewEntry(formatted_raw_ostream &OS,218                                          const TimelineViewEntry &Entry,219                                          unsigned Iteration,220                                          unsigned SourceIndex) const {221  if (Iteration == 0 && SourceIndex == 0)222    OS << '\n';223  OS << '[' << Iteration << ',' << SourceIndex << ']';224  OS.PadToColumn(10);225  assert(Entry.CycleDispatched >= 0 && "Invalid TimelineViewEntry!");226  unsigned CycleDispatched = static_cast<unsigned>(Entry.CycleDispatched);227  for (unsigned I = 0, E = CycleDispatched; I < E; ++I)228    OS << ((I % 5 == 0) ? '.' : ' ');229  OS << TimelineView::DisplayChar::Dispatched;230  if (CycleDispatched != Entry.CycleExecuted) {231    // Zero latency instructions have the same value for CycleDispatched,232    // CycleIssued and CycleExecuted.233    for (unsigned I = CycleDispatched + 1, E = Entry.CycleIssued; I < E; ++I)234      OS << TimelineView::DisplayChar::Waiting;235    if (Entry.CycleIssued == Entry.CycleExecuted)236      OS << TimelineView::DisplayChar::DisplayChar::Executed;237    else {238      if (CycleDispatched != Entry.CycleIssued)239        OS << TimelineView::DisplayChar::Executing;240      for (unsigned I = Entry.CycleIssued + 1, E = Entry.CycleExecuted; I < E;241           ++I)242        OS << TimelineView::DisplayChar::Executing;243      OS << TimelineView::DisplayChar::Executed;244    }245  }246 247  for (unsigned I = Entry.CycleExecuted + 1, E = Entry.CycleRetired; I < E; ++I)248    OS << TimelineView::DisplayChar::RetireLag;249  if (Entry.CycleExecuted < Entry.CycleRetired)250    OS << TimelineView::DisplayChar::Retired;251 252  // Skip other columns.253  for (unsigned I = Entry.CycleRetired + 1, E = LastCycle; I <= E; ++I)254    OS << ((I % 5 == 0 || I == LastCycle) ? '.' : ' ');255}256 257static void printTimelineHeader(formatted_raw_ostream &OS, unsigned Cycles) {258  OS << "\n\nTimeline view:\n";259  if (Cycles >= 10) {260    OS.PadToColumn(10);261    for (unsigned I = 0; I <= Cycles; ++I) {262      if (((I / 10) & 1) == 0)263        OS << ' ';264      else265        OS << I % 10;266    }267    OS << '\n';268  }269 270  OS << "Index";271  OS.PadToColumn(10);272  for (unsigned I = 0; I <= Cycles; ++I) {273    if (((I / 10) & 1) == 0)274      OS << I % 10;275    else276      OS << ' ';277  }278  OS << '\n';279}280 281void TimelineView::printTimeline(raw_ostream &OS) const {282  formatted_raw_ostream FOS(OS);283  printTimelineHeader(FOS, LastCycle);284  FOS.flush();285 286  unsigned IID = 0;287  ArrayRef<llvm::MCInst> Source = getSource();288  const unsigned Iterations = Timeline.size() / Source.size();289  for (unsigned Iteration = 0; Iteration < Iterations; ++Iteration) {290    for (const MCInst &Inst : Source) {291      const TimelineViewEntry &Entry = Timeline[IID];292      // When an instruction is retired after timeline-max-cycles,293      // its CycleRetired is left at 0. However, it's possible for294      // a 0 latency instruction to be retired during cycle 0 and we295      // don't want to early exit in that case. The CycleExecuted296      // attribute is set correctly whether or not it is greater297      // than timeline-max-cycles so we can use that to ensure298      // we don't early exit because of a 0 latency instruction.299      if (Entry.CycleRetired == 0 && Entry.CycleExecuted != 0) {300        FOS << "Truncated display due to cycle limit\n";301        return;302      }303 304      unsigned SourceIndex = IID % Source.size();305      printTimelineViewEntry(FOS, Entry, Iteration, SourceIndex);306      FOS << "   " << printInstructionString(Inst) << '\n';307      FOS.flush();308 309      ++IID;310    }311  }312}313 314json::Value TimelineView::toJSON() const {315  json::Array TimelineInfo;316 317  for (const TimelineViewEntry &TLE : Timeline) {318    // Check if the timeline-max-cycles has been reached.319    if (!TLE.CycleRetired && TLE.CycleExecuted)320      break;321 322    TimelineInfo.push_back(323        json::Object({{"CycleDispatched", TLE.CycleDispatched},324                      {"CycleReady", TLE.CycleReady},325                      {"CycleIssued", TLE.CycleIssued},326                      {"CycleExecuted", TLE.CycleExecuted},327                      {"CycleRetired", TLE.CycleRetired}}));328  }329  return json::Object({{"TimelineInfo", std::move(TimelineInfo)}});330}331} // namespace mca332} // namespace llvm333