//===--------------------- TimelineView.cpp ---------------------*- 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
//
//===----------------------------------------------------------------------===//
/// \brief
///
/// This file implements the TimelineView interface.
///
//===----------------------------------------------------------------------===//
#include "Views/TimelineView.h"
#include <numeric>
namespace llvm {
namespace mca {
TimelineView::TimelineView(const MCSubtargetInfo &sti, MCInstPrinter &Printer,
llvm::ArrayRef<llvm::MCInst> S, unsigned Iterations,
unsigned Cycles)
: InstructionView(sti, Printer, S), CurrentCycle(0),
MaxCycle(Cycles == 0 ? std::numeric_limits<unsigned>::max() : Cycles),
LastCycle(0), WaitTime(S.size()), UsedBuffer(S.size()) {
unsigned NumInstructions = getSource().size();
assert(Iterations && "Invalid number of iterations specified!");
NumInstructions *= Iterations;
Timeline.resize(NumInstructions);
TimelineViewEntry InvalidTVEntry = {-1, 0, 0, 0, 0};
std::fill(Timeline.begin(), Timeline.end(), InvalidTVEntry);
WaitTimeEntry NullWTEntry = {0, 0, 0};
std::fill(WaitTime.begin(), WaitTime.end(), NullWTEntry);
std::pair<unsigned, int> NullUsedBufferEntry = {/* Invalid resource ID*/ 0,
/* unknown buffer size */ -1};
std::fill(UsedBuffer.begin(), UsedBuffer.end(), NullUsedBufferEntry);
}
void TimelineView::onReservedBuffers(const InstRef &IR,
ArrayRef<unsigned> Buffers) {
if (IR.getSourceIndex() >= getSource().size())
return;
const MCSchedModel &SM = getSubTargetInfo().getSchedModel();
std::pair<unsigned, int> BufferInfo = {0, -1};
for (const unsigned Buffer : Buffers) {
const MCProcResourceDesc &MCDesc = *SM.getProcResource(Buffer);
if (!BufferInfo.first || BufferInfo.second > MCDesc.BufferSize) {
BufferInfo.first = Buffer;
BufferInfo.second = MCDesc.BufferSize;
}
}
UsedBuffer[IR.getSourceIndex()] = BufferInfo;
}
void TimelineView::onEvent(const HWInstructionEvent &Event) {
const unsigned Index = Event.IR.getSourceIndex();
if (Index >= Timeline.size())
return;
switch (Event.Type) {
case HWInstructionEvent::Retired: {
TimelineViewEntry &TVEntry = Timeline[Index];
if (CurrentCycle < MaxCycle)
TVEntry.CycleRetired = CurrentCycle;
// Update the WaitTime entry which corresponds to this Index.
assert(TVEntry.CycleDispatched >= 0 && "Invalid TVEntry found!");
unsigned CycleDispatched = static_cast<unsigned>(TVEntry.CycleDispatched);
WaitTimeEntry &WTEntry = WaitTime[Index % getSource().size()];
WTEntry.CyclesSpentInSchedulerQueue +=
TVEntry.CycleIssued - CycleDispatched;
assert(CycleDispatched <= TVEntry.CycleReady &&
"Instruction cannot be ready if it hasn't been dispatched yet!");
WTEntry.CyclesSpentInSQWhileReady +=
TVEntry.CycleIssued - TVEntry.CycleReady;
if (CurrentCycle > TVEntry.CycleExecuted) {
WTEntry.CyclesSpentAfterWBAndBeforeRetire +=
(CurrentCycle - 1) - TVEntry.CycleExecuted;
}
break;
}
case HWInstructionEvent::Ready:
Timeline[Index].CycleReady = CurrentCycle;
break;
case HWInstructionEvent::Issued:
Timeline[Index].CycleIssued = CurrentCycle;
break;
case HWInstructionEvent::Executed:
Timeline[Index].CycleExecuted = CurrentCycle;
break;
case HWInstructionEvent::Dispatched:
// There may be multiple dispatch events. Microcoded instructions that are
// expanded into multiple uOps may require multiple dispatch cycles. Here,
// we want to capture the first dispatch cycle.
if (Timeline[Index].CycleDispatched == -1)
Timeline[Index].CycleDispatched = static_cast<int>(CurrentCycle);
break;
default:
return;
}
if (CurrentCycle < MaxCycle)
LastCycle = std::max(LastCycle, CurrentCycle);
}
static raw_ostream::Colors chooseColor(unsigned CumulativeCycles,
unsigned Executions, int BufferSize) {
if (CumulativeCycles && BufferSize < 0)
return raw_ostream::MAGENTA;
unsigned Size = static_cast<unsigned>(BufferSize);
if (CumulativeCycles >= Size * Executions)
return raw_ostream::RED;
if ((CumulativeCycles * 2) >= Size * Executions)
return raw_ostream::YELLOW;
return raw_ostream::SAVEDCOLOR;
}
static void tryChangeColor(raw_ostream &OS, unsigned Cycles,
unsigned Executions, int BufferSize) {
if (!OS.has_colors())
return;
raw_ostream::Colors Color = chooseColor(Cycles, Executions, BufferSize);
if (Color == raw_ostream::SAVEDCOLOR) {
OS.resetColor();
return;
}
OS.changeColor(Color, /* bold */ true, /* BG */ false);
}
void TimelineView::printWaitTimeEntry(formatted_raw_ostream &OS,
const WaitTimeEntry &Entry,
unsigned SourceIndex,
unsigned Executions) const {
bool PrintingTotals = SourceIndex == getSource().size();
unsigned CumulativeExecutions = PrintingTotals ? Timeline.size() : Executions;
if (!PrintingTotals)
OS << SourceIndex << '.';
OS.PadToColumn(7);
double AverageTime1, AverageTime2, AverageTime3;
AverageTime1 =
(double)Entry.CyclesSpentInSchedulerQueue / CumulativeExecutions;
AverageTime2 = (double)Entry.CyclesSpentInSQWhileReady / CumulativeExecutions;
AverageTime3 =
(double)Entry.CyclesSpentAfterWBAndBeforeRetire / CumulativeExecutions;
OS << Executions;
OS.PadToColumn(13);
int BufferSize = PrintingTotals ? 0 : UsedBuffer[SourceIndex].second;
if (!PrintingTotals)
tryChangeColor(OS, Entry.CyclesSpentInSchedulerQueue, CumulativeExecutions,
BufferSize);
OS << format("%.1f", floor((AverageTime1 * 10) + 0.5) / 10);
OS.PadToColumn(20);
if (!PrintingTotals)
tryChangeColor(OS, Entry.CyclesSpentInSQWhileReady, CumulativeExecutions,
BufferSize);
OS << format("%.1f", floor((AverageTime2 * 10) + 0.5) / 10);
OS.PadToColumn(27);
if (!PrintingTotals)
tryChangeColor(OS, Entry.CyclesSpentAfterWBAndBeforeRetire,
CumulativeExecutions,
getSubTargetInfo().getSchedModel().MicroOpBufferSize);
OS << format("%.1f", floor((AverageTime3 * 10) + 0.5) / 10);
if (OS.has_colors())
OS.resetColor();
OS.PadToColumn(34);
}
void TimelineView::printAverageWaitTimes(raw_ostream &OS) const {
std::string Header =
"\n\nAverage Wait times (based on the timeline view):\n"
"[0]: Executions\n"
"[1]: Average time spent waiting in a scheduler's queue\n"
"[2]: Average time spent waiting in a scheduler's queue while ready\n"
"[3]: Average time elapsed from WB until retire stage\n\n"
" [0] [1] [2] [3]\n";
OS << Header;
formatted_raw_ostream FOS(OS);
unsigned Executions = Timeline.size() / getSource().size();
unsigned IID = 0;
for (const MCInst &Inst : getSource()) {
printWaitTimeEntry(FOS, WaitTime[IID], IID, Executions);
FOS << " " << printInstructionString(Inst) << '\n';
FOS.flush();
++IID;
}
// If the timeline contains more than one instruction,
// let's also print global averages.
if (getSource().size() != 1) {
WaitTimeEntry TotalWaitTime = std::accumulate(
WaitTime.begin(), WaitTime.end(), WaitTimeEntry{0, 0, 0},
[](const WaitTimeEntry &A, const WaitTimeEntry &B) {
return WaitTimeEntry{
A.CyclesSpentInSchedulerQueue + B.CyclesSpentInSchedulerQueue,
A.CyclesSpentInSQWhileReady + B.CyclesSpentInSQWhileReady,
A.CyclesSpentAfterWBAndBeforeRetire +
B.CyclesSpentAfterWBAndBeforeRetire};
});
printWaitTimeEntry(FOS, TotalWaitTime, IID, Executions);
FOS << " "
<< "<total>" << '\n';
FOS.flush();
}
}
void TimelineView::printTimelineViewEntry(formatted_raw_ostream &OS,
const TimelineViewEntry &Entry,
unsigned Iteration,
unsigned SourceIndex) const {
if (Iteration == 0 && SourceIndex == 0)
OS << '\n';
OS << '[' << Iteration << ',' << SourceIndex << ']';
OS.PadToColumn(10);
assert(Entry.CycleDispatched >= 0 && "Invalid TimelineViewEntry!");
unsigned CycleDispatched = static_cast<unsigned>(Entry.CycleDispatched);
for (unsigned I = 0, E = CycleDispatched; I < E; ++I)
OS << ((I % 5 == 0) ? '.' : ' ');
OS << TimelineView::DisplayChar::Dispatched;
if (CycleDispatched != Entry.CycleExecuted) {
// Zero latency instructions have the same value for CycleDispatched,
// CycleIssued and CycleExecuted.
for (unsigned I = CycleDispatched + 1, E = Entry.CycleIssued; I < E; ++I)
OS << TimelineView::DisplayChar::Waiting;
if (Entry.CycleIssued == Entry.CycleExecuted)
OS << TimelineView::DisplayChar::DisplayChar::Executed;
else {
if (CycleDispatched != Entry.CycleIssued)
OS << TimelineView::DisplayChar::Executing;
for (unsigned I = Entry.CycleIssued + 1, E = Entry.CycleExecuted; I < E;
++I)
OS << TimelineView::DisplayChar::Executing;
OS << TimelineView::DisplayChar::Executed;
}
}
for (unsigned I = Entry.CycleExecuted + 1, E = Entry.CycleRetired; I < E; ++I)
OS << TimelineView::DisplayChar::RetireLag;
if (Entry.CycleExecuted < Entry.CycleRetired)
OS << TimelineView::DisplayChar::Retired;
// Skip other columns.
for (unsigned I = Entry.CycleRetired + 1, E = LastCycle; I <= E; ++I)
OS << ((I % 5 == 0 || I == LastCycle) ? '.' : ' ');
}
static void printTimelineHeader(formatted_raw_ostream &OS, unsigned Cycles) {
OS << "\n\nTimeline view:\n";
if (Cycles >= 10) {
OS.PadToColumn(10);
for (unsigned I = 0; I <= Cycles; ++I) {
if (((I / 10) & 1) == 0)
OS << ' ';
else
OS << I % 10;
}
OS << '\n';
}
OS << "Index";
OS.PadToColumn(10);
for (unsigned I = 0; I <= Cycles; ++I) {
if (((I / 10) & 1) == 0)
OS << I % 10;
else
OS << ' ';
}
OS << '\n';
}
void TimelineView::printTimeline(raw_ostream &OS) const {
formatted_raw_ostream FOS(OS);
printTimelineHeader(FOS, LastCycle);
FOS.flush();
unsigned IID = 0;
ArrayRef<llvm::MCInst> Source = getSource();
const unsigned Iterations = Timeline.size() / Source.size();
for (unsigned Iteration = 0; Iteration < Iterations; ++Iteration) {
for (const MCInst &Inst : Source) {
const TimelineViewEntry &Entry = Timeline[IID];
// When an instruction is retired after timeline-max-cycles,
// its CycleRetired is left at 0. However, it's possible for
// a 0 latency instruction to be retired during cycle 0 and we
// don't want to early exit in that case. The CycleExecuted
// attribute is set correctly whether or not it is greater
// than timeline-max-cycles so we can use that to ensure
// we don't early exit because of a 0 latency instruction.
if (Entry.CycleRetired == 0 && Entry.CycleExecuted != 0)
return;
unsigned SourceIndex = IID % Source.size();
printTimelineViewEntry(FOS, Entry, Iteration, SourceIndex);
FOS << " " << printInstructionString(Inst) << '\n';
FOS.flush();
++IID;
}
}
}
json::Value TimelineView::toJSON() const {
json::Array TimelineInfo;
for (const TimelineViewEntry &TLE : Timeline) {
TimelineInfo.push_back(
json::Object({{"CycleDispatched", TLE.CycleDispatched},
{"CycleReady", TLE.CycleReady},
{"CycleIssued", TLE.CycleIssued},
{"CycleExecuted", TLE.CycleExecuted},
{"CycleRetired", TLE.CycleRetired}}));
}
return json::Object({{"TimelineInfo", std::move(TimelineInfo)}});
}
} // namespace mca
} // namespace llvm
