xref: /freebsd/contrib/llvm-project/llvm/tools/llvm-mca/Views/TimelineView.cpp (revision dc318a4ffabcbfa23bb56a33403aad36e6de30af)
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-exception
6 //
7 //===----------------------------------------------------------------------===//
8 /// \brief
9 ///
10 /// This file implements the TimelineView interface.
11 ///
12 //===----------------------------------------------------------------------===//
13 
14 #include "Views/TimelineView.h"
15 #include <numeric>
16 
17 namespace llvm {
18 namespace mca {
19 
20 TimelineView::TimelineView(const MCSubtargetInfo &sti, MCInstPrinter &Printer,
21                            llvm::ArrayRef<llvm::MCInst> S, unsigned Iterations,
22                            unsigned Cycles)
23     : STI(sti), MCIP(Printer), Source(S), CurrentCycle(0),
24       MaxCycle(Cycles == 0 ? 80 : Cycles), LastCycle(0), WaitTime(S.size()),
25       UsedBuffer(S.size()) {
26   unsigned NumInstructions = Source.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   std::fill(Timeline.begin(), Timeline.end(), InvalidTVEntry);
32 
33   WaitTimeEntry NullWTEntry = {0, 0, 0};
34   std::fill(WaitTime.begin(), WaitTime.end(), NullWTEntry);
35 
36   std::pair<unsigned, int> NullUsedBufferEntry = {/* Invalid resource ID*/ 0,
37                                                   /* unknown buffer size */ -1};
38   std::fill(UsedBuffer.begin(), UsedBuffer.end(), NullUsedBufferEntry);
39 }
40 
41 void TimelineView::onReservedBuffers(const InstRef &IR,
42                                      ArrayRef<unsigned> Buffers) {
43   if (IR.getSourceIndex() >= Source.size())
44     return;
45 
46   const MCSchedModel &SM = STI.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 
59 void 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 % Source.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     WTEntry.CyclesSpentAfterWBAndBeforeRetire +=
81         (CurrentCycle - 1) - TVEntry.CycleExecuted;
82     break;
83   }
84   case HWInstructionEvent::Ready:
85     Timeline[Index].CycleReady = CurrentCycle;
86     break;
87   case HWInstructionEvent::Issued:
88     Timeline[Index].CycleIssued = CurrentCycle;
89     break;
90   case HWInstructionEvent::Executed:
91     Timeline[Index].CycleExecuted = CurrentCycle;
92     break;
93   case HWInstructionEvent::Dispatched:
94     // There may be multiple dispatch events. Microcoded instructions that are
95     // expanded into multiple uOps may require multiple dispatch cycles. Here,
96     // we want to capture the first dispatch cycle.
97     if (Timeline[Index].CycleDispatched == -1)
98       Timeline[Index].CycleDispatched = static_cast<int>(CurrentCycle);
99     break;
100   default:
101     return;
102   }
103   if (CurrentCycle < MaxCycle)
104     LastCycle = std::max(LastCycle, CurrentCycle);
105 }
106 
107 static raw_ostream::Colors chooseColor(unsigned CumulativeCycles,
108                                        unsigned Executions, int BufferSize) {
109   if (CumulativeCycles && BufferSize < 0)
110     return raw_ostream::MAGENTA;
111   unsigned Size = static_cast<unsigned>(BufferSize);
112   if (CumulativeCycles >= Size * Executions)
113     return raw_ostream::RED;
114   if ((CumulativeCycles * 2) >= Size * Executions)
115     return raw_ostream::YELLOW;
116   return raw_ostream::SAVEDCOLOR;
117 }
118 
119 static void tryChangeColor(raw_ostream &OS, unsigned Cycles,
120                            unsigned Executions, int BufferSize) {
121   if (!OS.has_colors())
122     return;
123 
124   raw_ostream::Colors Color = chooseColor(Cycles, Executions, BufferSize);
125   if (Color == raw_ostream::SAVEDCOLOR) {
126     OS.resetColor();
127     return;
128   }
129   OS.changeColor(Color, /* bold */ true, /* BG */ false);
130 }
131 
132 void TimelineView::printWaitTimeEntry(formatted_raw_ostream &OS,
133                                       const WaitTimeEntry &Entry,
134                                       unsigned SourceIndex,
135                                       unsigned Executions) const {
136   bool PrintingTotals = SourceIndex == Source.size();
137   unsigned CumulativeExecutions = PrintingTotals ? Timeline.size() : Executions;
138 
139   if (!PrintingTotals)
140     OS << SourceIndex << '.';
141 
142   OS.PadToColumn(7);
143 
144   double AverageTime1, AverageTime2, AverageTime3;
145   AverageTime1 =
146       (double)Entry.CyclesSpentInSchedulerQueue / CumulativeExecutions;
147   AverageTime2 = (double)Entry.CyclesSpentInSQWhileReady / CumulativeExecutions;
148   AverageTime3 =
149       (double)Entry.CyclesSpentAfterWBAndBeforeRetire / CumulativeExecutions;
150 
151   OS << Executions;
152   OS.PadToColumn(13);
153 
154   int BufferSize = PrintingTotals ? 0 : UsedBuffer[SourceIndex].second;
155   if (!PrintingTotals)
156     tryChangeColor(OS, Entry.CyclesSpentInSchedulerQueue, CumulativeExecutions,
157                    BufferSize);
158   OS << format("%.1f", floor((AverageTime1 * 10) + 0.5) / 10);
159   OS.PadToColumn(20);
160   if (!PrintingTotals)
161     tryChangeColor(OS, Entry.CyclesSpentInSQWhileReady, CumulativeExecutions,
162                    BufferSize);
163   OS << format("%.1f", floor((AverageTime2 * 10) + 0.5) / 10);
164   OS.PadToColumn(27);
165   if (!PrintingTotals)
166     tryChangeColor(OS, Entry.CyclesSpentAfterWBAndBeforeRetire,
167                    CumulativeExecutions, STI.getSchedModel().MicroOpBufferSize);
168   OS << format("%.1f", floor((AverageTime3 * 10) + 0.5) / 10);
169 
170   if (OS.has_colors())
171     OS.resetColor();
172   OS.PadToColumn(34);
173 }
174 
175 void TimelineView::printAverageWaitTimes(raw_ostream &OS) const {
176   std::string Header =
177       "\n\nAverage Wait times (based on the timeline view):\n"
178       "[0]: Executions\n"
179       "[1]: Average time spent waiting in a scheduler's queue\n"
180       "[2]: Average time spent waiting in a scheduler's queue while ready\n"
181       "[3]: Average time elapsed from WB until retire stage\n\n"
182       "      [0]    [1]    [2]    [3]\n";
183   OS << Header;
184 
185   // Use a different string stream for printing instructions.
186   std::string Instruction;
187   raw_string_ostream InstrStream(Instruction);
188 
189   formatted_raw_ostream FOS(OS);
190   unsigned Executions = Timeline.size() / Source.size();
191   unsigned IID = 0;
192   for (const MCInst &Inst : Source) {
193     printWaitTimeEntry(FOS, WaitTime[IID], IID, Executions);
194     // Append the instruction info at the end of the line.
195     MCIP.printInst(&Inst, 0, "", STI, InstrStream);
196     InstrStream.flush();
197 
198     // Consume any tabs or spaces at the beginning of the string.
199     StringRef Str(Instruction);
200     Str = Str.ltrim();
201     FOS << "   " << Str << '\n';
202     FOS.flush();
203     Instruction = "";
204 
205     ++IID;
206   }
207 
208   // If the timeline contains more than one instruction,
209   // let's also print global averages.
210   if (Source.size() != 1) {
211     WaitTimeEntry TotalWaitTime = std::accumulate(
212         WaitTime.begin(), WaitTime.end(), WaitTimeEntry{0, 0, 0},
213         [](const WaitTimeEntry &A, const WaitTimeEntry &B) {
214           return WaitTimeEntry{
215               A.CyclesSpentInSchedulerQueue + B.CyclesSpentInSchedulerQueue,
216               A.CyclesSpentInSQWhileReady + B.CyclesSpentInSQWhileReady,
217               A.CyclesSpentAfterWBAndBeforeRetire +
218                   B.CyclesSpentAfterWBAndBeforeRetire};
219         });
220     printWaitTimeEntry(FOS, TotalWaitTime, IID, Executions);
221     FOS << "   "
222         << "<total>" << '\n';
223     InstrStream.flush();
224   }
225 }
226 
227 void TimelineView::printTimelineViewEntry(formatted_raw_ostream &OS,
228                                           const TimelineViewEntry &Entry,
229                                           unsigned Iteration,
230                                           unsigned SourceIndex) const {
231   if (Iteration == 0 && SourceIndex == 0)
232     OS << '\n';
233   OS << '[' << Iteration << ',' << SourceIndex << ']';
234   OS.PadToColumn(10);
235   assert(Entry.CycleDispatched >= 0 && "Invalid TimelineViewEntry!");
236   unsigned CycleDispatched = static_cast<unsigned>(Entry.CycleDispatched);
237   for (unsigned I = 0, E = CycleDispatched; I < E; ++I)
238     OS << ((I % 5 == 0) ? '.' : ' ');
239   OS << TimelineView::DisplayChar::Dispatched;
240   if (CycleDispatched != Entry.CycleExecuted) {
241     // Zero latency instructions have the same value for CycleDispatched,
242     // CycleIssued and CycleExecuted.
243     for (unsigned I = CycleDispatched + 1, E = Entry.CycleIssued; I < E; ++I)
244       OS << TimelineView::DisplayChar::Waiting;
245     if (Entry.CycleIssued == Entry.CycleExecuted)
246       OS << TimelineView::DisplayChar::DisplayChar::Executed;
247     else {
248       if (CycleDispatched != Entry.CycleIssued)
249         OS << TimelineView::DisplayChar::Executing;
250       for (unsigned I = Entry.CycleIssued + 1, E = Entry.CycleExecuted; I < E;
251            ++I)
252         OS << TimelineView::DisplayChar::Executing;
253       OS << TimelineView::DisplayChar::Executed;
254     }
255   }
256 
257   for (unsigned I = Entry.CycleExecuted + 1, E = Entry.CycleRetired; I < E; ++I)
258     OS << TimelineView::DisplayChar::RetireLag;
259   OS << TimelineView::DisplayChar::Retired;
260 
261   // Skip other columns.
262   for (unsigned I = Entry.CycleRetired + 1, E = LastCycle; I <= E; ++I)
263     OS << ((I % 5 == 0 || I == LastCycle) ? '.' : ' ');
264 }
265 
266 static void printTimelineHeader(formatted_raw_ostream &OS, unsigned Cycles) {
267   OS << "\n\nTimeline view:\n";
268   if (Cycles >= 10) {
269     OS.PadToColumn(10);
270     for (unsigned I = 0; I <= Cycles; ++I) {
271       if (((I / 10) & 1) == 0)
272         OS << ' ';
273       else
274         OS << I % 10;
275     }
276     OS << '\n';
277   }
278 
279   OS << "Index";
280   OS.PadToColumn(10);
281   for (unsigned I = 0; I <= Cycles; ++I) {
282     if (((I / 10) & 1) == 0)
283       OS << I % 10;
284     else
285       OS << ' ';
286   }
287   OS << '\n';
288 }
289 
290 void TimelineView::printTimeline(raw_ostream &OS) const {
291   formatted_raw_ostream FOS(OS);
292   printTimelineHeader(FOS, LastCycle);
293   FOS.flush();
294 
295   // Use a different string stream for the instruction.
296   std::string Instruction;
297   raw_string_ostream InstrStream(Instruction);
298 
299   unsigned IID = 0;
300   const unsigned Iterations = Timeline.size() / Source.size();
301   for (unsigned Iteration = 0; Iteration < Iterations; ++Iteration) {
302     for (const MCInst &Inst : Source) {
303       const TimelineViewEntry &Entry = Timeline[IID];
304       if (Entry.CycleRetired == 0)
305         return;
306 
307       unsigned SourceIndex = IID % Source.size();
308       printTimelineViewEntry(FOS, Entry, Iteration, SourceIndex);
309       // Append the instruction info at the end of the line.
310       MCIP.printInst(&Inst, 0, "", STI, InstrStream);
311       InstrStream.flush();
312 
313       // Consume any tabs or spaces at the beginning of the string.
314       StringRef Str(Instruction);
315       Str = Str.ltrim();
316       FOS << "   " << Str << '\n';
317       FOS.flush();
318       Instruction = "";
319 
320       ++IID;
321     }
322   }
323 }
324 } // namespace mca
325 } // namespace llvm
326