llvm/lib/Analysis/ProfileSummaryInfo.cpp - llvm-project - Git at Google

 //===- 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;

 // Knobs for profile summary based thresholds.
 extern cl::opt<int> ProfileSummaryCutoffHot;
 extern cl::opt<int> ProfileSummaryCutoffCold;
 extern cl::opt<unsigned> ProfileSummaryHugeWorkingSetSizeThreshold;
 extern cl::opt<unsigned> ProfileSummaryLargeWorkingSetSizeThreshold;
 extern cl::opt<int> ProfileSummaryHotCount;
 extern cl::opt<int> ProfileSummaryColdCount;

 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 =
       ProfileSummaryBuilder::getHotCountThreshold(DetailedSummary);
   ColdCountThreshold =
       ProfileSummaryBuilder::getColdCountThreshold(DetailedSummary);
   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.getValueOr(UINT64_MAX);
 }

 uint64_t ProfileSummaryInfo::getOrCompColdCountThreshold() const {
   return ColdCountThreshold.getValueOr(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;
	//===- 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;

	// Knobs for profile summary based thresholds.
	extern cl::opt<int> ProfileSummaryCutoffHot;
	extern cl::opt<int> ProfileSummaryCutoffCold;
	extern cl::opt<unsigned> ProfileSummaryHugeWorkingSetSizeThreshold;
	extern cl::opt<unsigned> ProfileSummaryLargeWorkingSetSizeThreshold;
	extern cl::opt<int> ProfileSummaryHotCount;
	extern cl::opt<int> ProfileSummaryColdCount;

	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 =
	ProfileSummaryBuilder::getHotCountThreshold(DetailedSummary);
	ColdCountThreshold =
	ProfileSummaryBuilder::getColdCountThreshold(DetailedSummary);
	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.getValueOr(UINT64_MAX);
	}

	uint64_t ProfileSummaryInfo::getOrCompColdCountThreshold() const {
	return ColdCountThreshold.getValueOr(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;