462 lines
18 KiB
C++
462 lines
18 KiB
C++
//===- ProfileSummaryInfo.cpp - Global profile summary information --------===//
|
|
//
|
|
// 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
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file contains a pass that provides access to the global profile summary
|
|
// information.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/Analysis/ProfileSummaryInfo.h"
|
|
#include "llvm/Analysis/BlockFrequencyInfo.h"
|
|
#include "llvm/IR/BasicBlock.h"
|
|
#include "llvm/IR/Instructions.h"
|
|
#include "llvm/IR/Metadata.h"
|
|
#include "llvm/IR/Module.h"
|
|
#include "llvm/IR/ProfileSummary.h"
|
|
#include "llvm/InitializePasses.h"
|
|
#include "llvm/ProfileData/ProfileCommon.h"
|
|
#include "llvm/Support/CommandLine.h"
|
|
using namespace llvm;
|
|
|
|
// The following two parameters determine the threshold for a count to be
|
|
// considered hot/cold. These two parameters are percentile values (multiplied
|
|
// by 10000). If the counts are sorted in descending order, the minimum count to
|
|
// reach ProfileSummaryCutoffHot gives the threshold to determine a hot count.
|
|
// Similarly, the minimum count to reach ProfileSummaryCutoffCold gives the
|
|
// threshold for determining cold count (everything <= this threshold is
|
|
// considered cold).
|
|
|
|
static cl::opt<int> ProfileSummaryCutoffHot(
|
|
"profile-summary-cutoff-hot", cl::Hidden, cl::init(990000), cl::ZeroOrMore,
|
|
cl::desc("A count is hot if it exceeds the minimum count to"
|
|
" reach this percentile of total counts."));
|
|
|
|
static cl::opt<int> ProfileSummaryCutoffCold(
|
|
"profile-summary-cutoff-cold", cl::Hidden, cl::init(999999), cl::ZeroOrMore,
|
|
cl::desc("A count is cold if it is below the minimum count"
|
|
" to reach this percentile of total counts."));
|
|
|
|
static cl::opt<unsigned> ProfileSummaryHugeWorkingSetSizeThreshold(
|
|
"profile-summary-huge-working-set-size-threshold", cl::Hidden,
|
|
cl::init(15000), cl::ZeroOrMore,
|
|
cl::desc("The code working set size is considered huge if the number of"
|
|
" blocks required to reach the -profile-summary-cutoff-hot"
|
|
" percentile exceeds this count."));
|
|
|
|
static cl::opt<unsigned> ProfileSummaryLargeWorkingSetSizeThreshold(
|
|
"profile-summary-large-working-set-size-threshold", cl::Hidden,
|
|
cl::init(12500), cl::ZeroOrMore,
|
|
cl::desc("The code working set size is considered large if the number of"
|
|
" blocks required to reach the -profile-summary-cutoff-hot"
|
|
" percentile exceeds this count."));
|
|
|
|
// The next two options override the counts derived from summary computation and
|
|
// are useful for debugging purposes.
|
|
static cl::opt<int> ProfileSummaryHotCount(
|
|
"profile-summary-hot-count", cl::ReallyHidden, cl::ZeroOrMore,
|
|
cl::desc("A fixed hot count that overrides the count derived from"
|
|
" profile-summary-cutoff-hot"));
|
|
|
|
static cl::opt<int> ProfileSummaryColdCount(
|
|
"profile-summary-cold-count", cl::ReallyHidden, cl::ZeroOrMore,
|
|
cl::desc("A fixed cold count that overrides the count derived from"
|
|
" profile-summary-cutoff-cold"));
|
|
|
|
static cl::opt<bool> PartialProfile(
|
|
"partial-profile", cl::Hidden, cl::init(false),
|
|
cl::desc("Specify the current profile is used as a partial profile."));
|
|
|
|
cl::opt<bool> ScalePartialSampleProfileWorkingSetSize(
|
|
"scale-partial-sample-profile-working-set-size", cl::Hidden, cl::init(true),
|
|
cl::desc(
|
|
"If true, scale the working set size of the partial sample profile "
|
|
"by the partial profile ratio to reflect the size of the program "
|
|
"being compiled."));
|
|
|
|
static cl::opt<double> PartialSampleProfileWorkingSetSizeScaleFactor(
|
|
"partial-sample-profile-working-set-size-scale-factor", cl::Hidden,
|
|
cl::init(0.008),
|
|
cl::desc("The scale factor used to scale the working set size of the "
|
|
"partial sample profile along with the partial profile ratio. "
|
|
"This includes the factor of the profile counter per block "
|
|
"and the factor to scale the working set size to use the same "
|
|
"shared thresholds as PGO."));
|
|
|
|
// The profile summary metadata may be attached either by the frontend or by
|
|
// any backend passes (IR level instrumentation, for example). This method
|
|
// checks if the Summary is null and if so checks if the summary metadata is now
|
|
// available in the module and parses it to get the Summary object.
|
|
void ProfileSummaryInfo::refresh() {
|
|
if (hasProfileSummary())
|
|
return;
|
|
// First try to get context sensitive ProfileSummary.
|
|
auto *SummaryMD = M.getProfileSummary(/* IsCS */ true);
|
|
if (SummaryMD)
|
|
Summary.reset(ProfileSummary::getFromMD(SummaryMD));
|
|
|
|
if (!hasProfileSummary()) {
|
|
// This will actually return PSK_Instr or PSK_Sample summary.
|
|
SummaryMD = M.getProfileSummary(/* IsCS */ false);
|
|
if (SummaryMD)
|
|
Summary.reset(ProfileSummary::getFromMD(SummaryMD));
|
|
}
|
|
if (!hasProfileSummary())
|
|
return;
|
|
computeThresholds();
|
|
}
|
|
|
|
Optional<uint64_t> ProfileSummaryInfo::getProfileCount(
|
|
const CallBase &Call, BlockFrequencyInfo *BFI, bool AllowSynthetic) const {
|
|
assert((isa<CallInst>(Call) || isa<InvokeInst>(Call)) &&
|
|
"We can only get profile count for call/invoke instruction.");
|
|
if (hasSampleProfile()) {
|
|
// In sample PGO mode, check if there is a profile metadata on the
|
|
// instruction. If it is present, determine hotness solely based on that,
|
|
// since the sampled entry count may not be accurate. If there is no
|
|
// annotated on the instruction, return None.
|
|
uint64_t TotalCount;
|
|
if (Call.extractProfTotalWeight(TotalCount))
|
|
return TotalCount;
|
|
return None;
|
|
}
|
|
if (BFI)
|
|
return BFI->getBlockProfileCount(Call.getParent(), AllowSynthetic);
|
|
return None;
|
|
}
|
|
|
|
/// Returns true if the function's entry is hot. If it returns false, it
|
|
/// either means it is not hot or it is unknown whether it is hot or not (for
|
|
/// example, no profile data is available).
|
|
bool ProfileSummaryInfo::isFunctionEntryHot(const Function *F) const {
|
|
if (!F || !hasProfileSummary())
|
|
return false;
|
|
auto FunctionCount = F->getEntryCount();
|
|
// FIXME: The heuristic used below for determining hotness is based on
|
|
// preliminary SPEC tuning for inliner. This will eventually be a
|
|
// convenience method that calls isHotCount.
|
|
return FunctionCount && isHotCount(FunctionCount.getCount());
|
|
}
|
|
|
|
/// Returns true if the function contains hot code. This can include a hot
|
|
/// function entry count, hot basic block, or (in the case of Sample PGO)
|
|
/// hot total call edge count.
|
|
/// If it returns false, it either means it is not hot or it is unknown
|
|
/// (for example, no profile data is available).
|
|
bool ProfileSummaryInfo::isFunctionHotInCallGraph(
|
|
const Function *F, BlockFrequencyInfo &BFI) const {
|
|
if (!F || !hasProfileSummary())
|
|
return false;
|
|
if (auto FunctionCount = F->getEntryCount())
|
|
if (isHotCount(FunctionCount.getCount()))
|
|
return true;
|
|
|
|
if (hasSampleProfile()) {
|
|
uint64_t TotalCallCount = 0;
|
|
for (const auto &BB : *F)
|
|
for (const auto &I : BB)
|
|
if (isa<CallInst>(I) || isa<InvokeInst>(I))
|
|
if (auto CallCount = getProfileCount(cast<CallBase>(I), nullptr))
|
|
TotalCallCount += CallCount.getValue();
|
|
if (isHotCount(TotalCallCount))
|
|
return true;
|
|
}
|
|
for (const auto &BB : *F)
|
|
if (isHotBlock(&BB, &BFI))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
/// Returns true if the function only contains cold code. This means that
|
|
/// the function entry and blocks are all cold, and (in the case of Sample PGO)
|
|
/// the total call edge count is cold.
|
|
/// If it returns false, it either means it is not cold or it is unknown
|
|
/// (for example, no profile data is available).
|
|
bool ProfileSummaryInfo::isFunctionColdInCallGraph(
|
|
const Function *F, BlockFrequencyInfo &BFI) const {
|
|
if (!F || !hasProfileSummary())
|
|
return false;
|
|
if (auto FunctionCount = F->getEntryCount())
|
|
if (!isColdCount(FunctionCount.getCount()))
|
|
return false;
|
|
|
|
if (hasSampleProfile()) {
|
|
uint64_t TotalCallCount = 0;
|
|
for (const auto &BB : *F)
|
|
for (const auto &I : BB)
|
|
if (isa<CallInst>(I) || isa<InvokeInst>(I))
|
|
if (auto CallCount = getProfileCount(cast<CallBase>(I), nullptr))
|
|
TotalCallCount += CallCount.getValue();
|
|
if (!isColdCount(TotalCallCount))
|
|
return false;
|
|
}
|
|
for (const auto &BB : *F)
|
|
if (!isColdBlock(&BB, &BFI))
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isFunctionHotnessUnknown(const Function &F) const {
|
|
assert(hasPartialSampleProfile() && "Expect partial sample profile");
|
|
return !F.getEntryCount().hasValue();
|
|
}
|
|
|
|
template <bool isHot>
|
|
bool ProfileSummaryInfo::isFunctionHotOrColdInCallGraphNthPercentile(
|
|
int PercentileCutoff, const Function *F, BlockFrequencyInfo &BFI) const {
|
|
if (!F || !hasProfileSummary())
|
|
return false;
|
|
if (auto FunctionCount = F->getEntryCount()) {
|
|
if (isHot &&
|
|
isHotCountNthPercentile(PercentileCutoff, FunctionCount.getCount()))
|
|
return true;
|
|
if (!isHot &&
|
|
!isColdCountNthPercentile(PercentileCutoff, FunctionCount.getCount()))
|
|
return false;
|
|
}
|
|
if (hasSampleProfile()) {
|
|
uint64_t TotalCallCount = 0;
|
|
for (const auto &BB : *F)
|
|
for (const auto &I : BB)
|
|
if (isa<CallInst>(I) || isa<InvokeInst>(I))
|
|
if (auto CallCount = getProfileCount(cast<CallBase>(I), nullptr))
|
|
TotalCallCount += CallCount.getValue();
|
|
if (isHot && isHotCountNthPercentile(PercentileCutoff, TotalCallCount))
|
|
return true;
|
|
if (!isHot && !isColdCountNthPercentile(PercentileCutoff, TotalCallCount))
|
|
return false;
|
|
}
|
|
for (const auto &BB : *F) {
|
|
if (isHot && isHotBlockNthPercentile(PercentileCutoff, &BB, &BFI))
|
|
return true;
|
|
if (!isHot && !isColdBlockNthPercentile(PercentileCutoff, &BB, &BFI))
|
|
return false;
|
|
}
|
|
return !isHot;
|
|
}
|
|
|
|
// Like isFunctionHotInCallGraph but for a given cutoff.
|
|
bool ProfileSummaryInfo::isFunctionHotInCallGraphNthPercentile(
|
|
int PercentileCutoff, const Function *F, BlockFrequencyInfo &BFI) const {
|
|
return isFunctionHotOrColdInCallGraphNthPercentile<true>(
|
|
PercentileCutoff, F, BFI);
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isFunctionColdInCallGraphNthPercentile(
|
|
int PercentileCutoff, const Function *F, BlockFrequencyInfo &BFI) const {
|
|
return isFunctionHotOrColdInCallGraphNthPercentile<false>(
|
|
PercentileCutoff, F, BFI);
|
|
}
|
|
|
|
/// Returns true if the function's entry is a cold. If it returns false, it
|
|
/// either means it is not cold or it is unknown whether it is cold or not (for
|
|
/// example, no profile data is available).
|
|
bool ProfileSummaryInfo::isFunctionEntryCold(const Function *F) const {
|
|
if (!F)
|
|
return false;
|
|
if (F->hasFnAttribute(Attribute::Cold))
|
|
return true;
|
|
if (!hasProfileSummary())
|
|
return false;
|
|
auto FunctionCount = F->getEntryCount();
|
|
// FIXME: The heuristic used below for determining coldness is based on
|
|
// preliminary SPEC tuning for inliner. This will eventually be a
|
|
// convenience method that calls isHotCount.
|
|
return FunctionCount && isColdCount(FunctionCount.getCount());
|
|
}
|
|
|
|
/// Compute the hot and cold thresholds.
|
|
void ProfileSummaryInfo::computeThresholds() {
|
|
auto &DetailedSummary = Summary->getDetailedSummary();
|
|
auto &HotEntry = ProfileSummaryBuilder::getEntryForPercentile(
|
|
DetailedSummary, ProfileSummaryCutoffHot);
|
|
HotCountThreshold = HotEntry.MinCount;
|
|
if (ProfileSummaryHotCount.getNumOccurrences() > 0)
|
|
HotCountThreshold = ProfileSummaryHotCount;
|
|
auto &ColdEntry = ProfileSummaryBuilder::getEntryForPercentile(
|
|
DetailedSummary, ProfileSummaryCutoffCold);
|
|
ColdCountThreshold = ColdEntry.MinCount;
|
|
if (ProfileSummaryColdCount.getNumOccurrences() > 0)
|
|
ColdCountThreshold = ProfileSummaryColdCount;
|
|
assert(ColdCountThreshold <= HotCountThreshold &&
|
|
"Cold count threshold cannot exceed hot count threshold!");
|
|
if (!hasPartialSampleProfile() || !ScalePartialSampleProfileWorkingSetSize) {
|
|
HasHugeWorkingSetSize =
|
|
HotEntry.NumCounts > ProfileSummaryHugeWorkingSetSizeThreshold;
|
|
HasLargeWorkingSetSize =
|
|
HotEntry.NumCounts > ProfileSummaryLargeWorkingSetSizeThreshold;
|
|
} else {
|
|
// Scale the working set size of the partial sample profile to reflect the
|
|
// size of the program being compiled.
|
|
double PartialProfileRatio = Summary->getPartialProfileRatio();
|
|
uint64_t ScaledHotEntryNumCounts =
|
|
static_cast<uint64_t>(HotEntry.NumCounts * PartialProfileRatio *
|
|
PartialSampleProfileWorkingSetSizeScaleFactor);
|
|
HasHugeWorkingSetSize =
|
|
ScaledHotEntryNumCounts > ProfileSummaryHugeWorkingSetSizeThreshold;
|
|
HasLargeWorkingSetSize =
|
|
ScaledHotEntryNumCounts > ProfileSummaryLargeWorkingSetSizeThreshold;
|
|
}
|
|
}
|
|
|
|
Optional<uint64_t>
|
|
ProfileSummaryInfo::computeThreshold(int PercentileCutoff) const {
|
|
if (!hasProfileSummary())
|
|
return None;
|
|
auto iter = ThresholdCache.find(PercentileCutoff);
|
|
if (iter != ThresholdCache.end()) {
|
|
return iter->second;
|
|
}
|
|
auto &DetailedSummary = Summary->getDetailedSummary();
|
|
auto &Entry = ProfileSummaryBuilder::getEntryForPercentile(DetailedSummary,
|
|
PercentileCutoff);
|
|
uint64_t CountThreshold = Entry.MinCount;
|
|
ThresholdCache[PercentileCutoff] = CountThreshold;
|
|
return CountThreshold;
|
|
}
|
|
|
|
bool ProfileSummaryInfo::hasHugeWorkingSetSize() const {
|
|
return HasHugeWorkingSetSize && HasHugeWorkingSetSize.getValue();
|
|
}
|
|
|
|
bool ProfileSummaryInfo::hasLargeWorkingSetSize() const {
|
|
return HasLargeWorkingSetSize && HasLargeWorkingSetSize.getValue();
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isHotCount(uint64_t C) const {
|
|
return HotCountThreshold && C >= HotCountThreshold.getValue();
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isColdCount(uint64_t C) const {
|
|
return ColdCountThreshold && C <= ColdCountThreshold.getValue();
|
|
}
|
|
|
|
template <bool isHot>
|
|
bool ProfileSummaryInfo::isHotOrColdCountNthPercentile(int PercentileCutoff,
|
|
uint64_t C) const {
|
|
auto CountThreshold = computeThreshold(PercentileCutoff);
|
|
if (isHot)
|
|
return CountThreshold && C >= CountThreshold.getValue();
|
|
else
|
|
return CountThreshold && C <= CountThreshold.getValue();
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isHotCountNthPercentile(int PercentileCutoff,
|
|
uint64_t C) const {
|
|
return isHotOrColdCountNthPercentile<true>(PercentileCutoff, C);
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isColdCountNthPercentile(int PercentileCutoff,
|
|
uint64_t C) const {
|
|
return isHotOrColdCountNthPercentile<false>(PercentileCutoff, C);
|
|
}
|
|
|
|
uint64_t ProfileSummaryInfo::getOrCompHotCountThreshold() const {
|
|
return HotCountThreshold ? HotCountThreshold.getValue() : UINT64_MAX;
|
|
}
|
|
|
|
uint64_t ProfileSummaryInfo::getOrCompColdCountThreshold() const {
|
|
return ColdCountThreshold ? ColdCountThreshold.getValue() : 0;
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isHotBlock(const BasicBlock *BB,
|
|
BlockFrequencyInfo *BFI) const {
|
|
auto Count = BFI->getBlockProfileCount(BB);
|
|
return Count && isHotCount(*Count);
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isColdBlock(const BasicBlock *BB,
|
|
BlockFrequencyInfo *BFI) const {
|
|
auto Count = BFI->getBlockProfileCount(BB);
|
|
return Count && isColdCount(*Count);
|
|
}
|
|
|
|
template <bool isHot>
|
|
bool ProfileSummaryInfo::isHotOrColdBlockNthPercentile(
|
|
int PercentileCutoff, const BasicBlock *BB, BlockFrequencyInfo *BFI) const {
|
|
auto Count = BFI->getBlockProfileCount(BB);
|
|
if (isHot)
|
|
return Count && isHotCountNthPercentile(PercentileCutoff, *Count);
|
|
else
|
|
return Count && isColdCountNthPercentile(PercentileCutoff, *Count);
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isHotBlockNthPercentile(
|
|
int PercentileCutoff, const BasicBlock *BB, BlockFrequencyInfo *BFI) const {
|
|
return isHotOrColdBlockNthPercentile<true>(PercentileCutoff, BB, BFI);
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isColdBlockNthPercentile(
|
|
int PercentileCutoff, const BasicBlock *BB, BlockFrequencyInfo *BFI) const {
|
|
return isHotOrColdBlockNthPercentile<false>(PercentileCutoff, BB, BFI);
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isHotCallSite(const CallBase &CB,
|
|
BlockFrequencyInfo *BFI) const {
|
|
auto C = getProfileCount(CB, BFI);
|
|
return C && isHotCount(*C);
|
|
}
|
|
|
|
bool ProfileSummaryInfo::isColdCallSite(const CallBase &CB,
|
|
BlockFrequencyInfo *BFI) const {
|
|
auto C = getProfileCount(CB, BFI);
|
|
if (C)
|
|
return isColdCount(*C);
|
|
|
|
// In SamplePGO, if the caller has been sampled, and there is no profile
|
|
// annotated on the callsite, we consider the callsite as cold.
|
|
return hasSampleProfile() && CB.getCaller()->hasProfileData();
|
|
}
|
|
|
|
bool ProfileSummaryInfo::hasPartialSampleProfile() const {
|
|
return hasProfileSummary() &&
|
|
Summary->getKind() == ProfileSummary::PSK_Sample &&
|
|
(PartialProfile || Summary->isPartialProfile());
|
|
}
|
|
|
|
INITIALIZE_PASS(ProfileSummaryInfoWrapperPass, "profile-summary-info",
|
|
"Profile summary info", false, true)
|
|
|
|
ProfileSummaryInfoWrapperPass::ProfileSummaryInfoWrapperPass()
|
|
: ImmutablePass(ID) {
|
|
initializeProfileSummaryInfoWrapperPassPass(*PassRegistry::getPassRegistry());
|
|
}
|
|
|
|
bool ProfileSummaryInfoWrapperPass::doInitialization(Module &M) {
|
|
PSI.reset(new ProfileSummaryInfo(M));
|
|
return false;
|
|
}
|
|
|
|
bool ProfileSummaryInfoWrapperPass::doFinalization(Module &M) {
|
|
PSI.reset();
|
|
return false;
|
|
}
|
|
|
|
AnalysisKey ProfileSummaryAnalysis::Key;
|
|
ProfileSummaryInfo ProfileSummaryAnalysis::run(Module &M,
|
|
ModuleAnalysisManager &) {
|
|
return ProfileSummaryInfo(M);
|
|
}
|
|
|
|
PreservedAnalyses ProfileSummaryPrinterPass::run(Module &M,
|
|
ModuleAnalysisManager &AM) {
|
|
ProfileSummaryInfo &PSI = AM.getResult<ProfileSummaryAnalysis>(M);
|
|
|
|
OS << "Functions in " << M.getName() << " with hot/cold annotations: \n";
|
|
for (auto &F : M) {
|
|
OS << F.getName();
|
|
if (PSI.isFunctionEntryHot(&F))
|
|
OS << " :hot entry ";
|
|
else if (PSI.isFunctionEntryCold(&F))
|
|
OS << " :cold entry ";
|
|
OS << "\n";
|
|
}
|
|
return PreservedAnalyses::all();
|
|
}
|
|
|
|
char ProfileSummaryInfoWrapperPass::ID = 0;
|