|  | //===-- ModuleSummaryIndex.cpp - Module Summary Index ---------------------===// | 
|  | // | 
|  | // 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 implements the module index and summary classes for the | 
|  | // IR library. | 
|  | // | 
|  | //===----------------------------------------------------------------------===// | 
|  |  | 
|  | #include "llvm/IR/ModuleSummaryIndex.h" | 
|  | #include "llvm/ADT/SCCIterator.h" | 
|  | #include "llvm/ADT/Statistic.h" | 
|  | #include "llvm/Support/CommandLine.h" | 
|  | #include "llvm/Support/Path.h" | 
|  | #include "llvm/Support/raw_ostream.h" | 
|  | using namespace llvm; | 
|  |  | 
|  | #define DEBUG_TYPE "module-summary-index" | 
|  |  | 
|  | STATISTIC(ReadOnlyLiveGVars, | 
|  | "Number of live global variables marked read only"); | 
|  | STATISTIC(WriteOnlyLiveGVars, | 
|  | "Number of live global variables marked write only"); | 
|  |  | 
|  | static cl::opt<bool> PropagateAttrs("propagate-attrs", cl::init(true), | 
|  | cl::Hidden, | 
|  | cl::desc("Propagate attributes in index")); | 
|  |  | 
|  | static cl::opt<bool> ImportConstantsWithRefs( | 
|  | "import-constants-with-refs", cl::init(true), cl::Hidden, | 
|  | cl::desc("Import constant global variables with references")); | 
|  |  | 
|  | constexpr uint32_t FunctionSummary::ParamAccess::RangeWidth; | 
|  |  | 
|  | FunctionSummary FunctionSummary::ExternalNode = | 
|  | FunctionSummary::makeDummyFunctionSummary( | 
|  | SmallVector<FunctionSummary::EdgeTy, 0>()); | 
|  |  | 
|  | GlobalValue::VisibilityTypes ValueInfo::getELFVisibility() const { | 
|  | bool HasProtected = false; | 
|  | for (const auto &S : make_pointee_range(getSummaryList())) { | 
|  | if (S.getVisibility() == GlobalValue::HiddenVisibility) | 
|  | return GlobalValue::HiddenVisibility; | 
|  | if (S.getVisibility() == GlobalValue::ProtectedVisibility) | 
|  | HasProtected = true; | 
|  | } | 
|  | return HasProtected ? GlobalValue::ProtectedVisibility | 
|  | : GlobalValue::DefaultVisibility; | 
|  | } | 
|  |  | 
|  | bool ValueInfo::isDSOLocal(bool WithDSOLocalPropagation) const { | 
|  | // With DSOLocal propagation done, the flag in evey summary is the same. | 
|  | // Check the first one is enough. | 
|  | return WithDSOLocalPropagation | 
|  | ? getSummaryList().size() && getSummaryList()[0]->isDSOLocal() | 
|  | : getSummaryList().size() && | 
|  | llvm::all_of( | 
|  | getSummaryList(), | 
|  | [](const std::unique_ptr<GlobalValueSummary> &Summary) { | 
|  | return Summary->isDSOLocal(); | 
|  | }); | 
|  | } | 
|  |  | 
|  | bool ValueInfo::canAutoHide() const { | 
|  | // Can only auto hide if all copies are eligible to auto hide. | 
|  | return getSummaryList().size() && | 
|  | llvm::all_of(getSummaryList(), | 
|  | [](const std::unique_ptr<GlobalValueSummary> &Summary) { | 
|  | return Summary->canAutoHide(); | 
|  | }); | 
|  | } | 
|  |  | 
|  | // Gets the number of readonly and writeonly refs in RefEdgeList | 
|  | std::pair<unsigned, unsigned> FunctionSummary::specialRefCounts() const { | 
|  | // Here we take advantage of having all readonly and writeonly references | 
|  | // located in the end of the RefEdgeList. | 
|  | auto Refs = refs(); | 
|  | unsigned RORefCnt = 0, WORefCnt = 0; | 
|  | int I; | 
|  | for (I = Refs.size() - 1; I >= 0 && Refs[I].isWriteOnly(); --I) | 
|  | WORefCnt++; | 
|  | for (; I >= 0 && Refs[I].isReadOnly(); --I) | 
|  | RORefCnt++; | 
|  | return {RORefCnt, WORefCnt}; | 
|  | } | 
|  |  | 
|  | constexpr uint64_t ModuleSummaryIndex::BitcodeSummaryVersion; | 
|  |  | 
|  | uint64_t ModuleSummaryIndex::getFlags() const { | 
|  | uint64_t Flags = 0; | 
|  | // Flags & 0x4 is reserved. DO NOT REUSE. | 
|  | if (withGlobalValueDeadStripping()) | 
|  | Flags |= 0x1; | 
|  | if (skipModuleByDistributedBackend()) | 
|  | Flags |= 0x2; | 
|  | if (enableSplitLTOUnit()) | 
|  | Flags |= 0x8; | 
|  | if (partiallySplitLTOUnits()) | 
|  | Flags |= 0x10; | 
|  | if (withAttributePropagation()) | 
|  | Flags |= 0x20; | 
|  | if (withDSOLocalPropagation()) | 
|  | Flags |= 0x40; | 
|  | if (withWholeProgramVisibility()) | 
|  | Flags |= 0x80; | 
|  | if (withSupportsHotColdNew()) | 
|  | Flags |= 0x100; | 
|  | if (hasUnifiedLTO()) | 
|  | Flags |= 0x200; | 
|  | return Flags; | 
|  | } | 
|  |  | 
|  | void ModuleSummaryIndex::setFlags(uint64_t Flags) { | 
|  | assert(Flags <= 0x2ff && "Unexpected bits in flag"); | 
|  | // 1 bit: WithGlobalValueDeadStripping flag. | 
|  | // Set on combined index only. | 
|  | if (Flags & 0x1) | 
|  | setWithGlobalValueDeadStripping(); | 
|  | // 1 bit: SkipModuleByDistributedBackend flag. | 
|  | // Set on combined index only. | 
|  | if (Flags & 0x2) | 
|  | setSkipModuleByDistributedBackend(); | 
|  | // Flags & 0x4 is reserved. DO NOT REUSE. | 
|  | // 1 bit: DisableSplitLTOUnit flag. | 
|  | // Set on per module indexes. It is up to the client to validate | 
|  | // the consistency of this flag across modules being linked. | 
|  | if (Flags & 0x8) | 
|  | setEnableSplitLTOUnit(); | 
|  | // 1 bit: PartiallySplitLTOUnits flag. | 
|  | // Set on combined index only. | 
|  | if (Flags & 0x10) | 
|  | setPartiallySplitLTOUnits(); | 
|  | // 1 bit: WithAttributePropagation flag. | 
|  | // Set on combined index only. | 
|  | if (Flags & 0x20) | 
|  | setWithAttributePropagation(); | 
|  | // 1 bit: WithDSOLocalPropagation flag. | 
|  | // Set on combined index only. | 
|  | if (Flags & 0x40) | 
|  | setWithDSOLocalPropagation(); | 
|  | // 1 bit: WithWholeProgramVisibility flag. | 
|  | // Set on combined index only. | 
|  | if (Flags & 0x80) | 
|  | setWithWholeProgramVisibility(); | 
|  | // 1 bit: WithSupportsHotColdNew flag. | 
|  | // Set on combined index only. | 
|  | if (Flags & 0x100) | 
|  | setWithSupportsHotColdNew(); | 
|  | // 1 bit: WithUnifiedLTO flag. | 
|  | // Set on combined index only. | 
|  | if (Flags & 0x200) | 
|  | setUnifiedLTO(); | 
|  | } | 
|  |  | 
|  | // Collect for the given module the list of function it defines | 
|  | // (GUID -> Summary). | 
|  | void ModuleSummaryIndex::collectDefinedFunctionsForModule( | 
|  | StringRef ModulePath, GVSummaryMapTy &GVSummaryMap) const { | 
|  | for (auto &GlobalList : *this) { | 
|  | auto GUID = GlobalList.first; | 
|  | for (auto &GlobSummary : GlobalList.second.SummaryList) { | 
|  | auto *Summary = dyn_cast_or_null<FunctionSummary>(GlobSummary.get()); | 
|  | if (!Summary) | 
|  | // Ignore global variable, focus on functions | 
|  | continue; | 
|  | // Ignore summaries from other modules. | 
|  | if (Summary->modulePath() != ModulePath) | 
|  | continue; | 
|  | GVSummaryMap[GUID] = Summary; | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | GlobalValueSummary * | 
|  | ModuleSummaryIndex::getGlobalValueSummary(uint64_t ValueGUID, | 
|  | bool PerModuleIndex) const { | 
|  | auto VI = getValueInfo(ValueGUID); | 
|  | assert(VI && "GlobalValue not found in index"); | 
|  | assert((!PerModuleIndex || VI.getSummaryList().size() == 1) && | 
|  | "Expected a single entry per global value in per-module index"); | 
|  | auto &Summary = VI.getSummaryList()[0]; | 
|  | return Summary.get(); | 
|  | } | 
|  |  | 
|  | bool ModuleSummaryIndex::isGUIDLive(GlobalValue::GUID GUID) const { | 
|  | auto VI = getValueInfo(GUID); | 
|  | if (!VI) | 
|  | return true; | 
|  | const auto &SummaryList = VI.getSummaryList(); | 
|  | if (SummaryList.empty()) | 
|  | return true; | 
|  | for (auto &I : SummaryList) | 
|  | if (isGlobalValueLive(I.get())) | 
|  | return true; | 
|  | return false; | 
|  | } | 
|  |  | 
|  | static void | 
|  | propagateAttributesToRefs(GlobalValueSummary *S, | 
|  | DenseSet<ValueInfo> &MarkedNonReadWriteOnly) { | 
|  | // If reference is not readonly or writeonly then referenced summary is not | 
|  | // read/writeonly either. Note that: | 
|  | // - All references from GlobalVarSummary are conservatively considered as | 
|  | //   not readonly or writeonly. Tracking them properly requires more complex | 
|  | //   analysis then we have now. | 
|  | // | 
|  | // - AliasSummary objects have no refs at all so this function is a no-op | 
|  | //   for them. | 
|  | for (auto &VI : S->refs()) { | 
|  | assert(VI.getAccessSpecifier() == 0 || isa<FunctionSummary>(S)); | 
|  | if (!VI.getAccessSpecifier()) { | 
|  | if (!MarkedNonReadWriteOnly.insert(VI).second) | 
|  | continue; | 
|  | } else if (MarkedNonReadWriteOnly.contains(VI)) | 
|  | continue; | 
|  | for (auto &Ref : VI.getSummaryList()) | 
|  | // If references to alias is not read/writeonly then aliasee | 
|  | // is not read/writeonly | 
|  | if (auto *GVS = dyn_cast<GlobalVarSummary>(Ref->getBaseObject())) { | 
|  | if (!VI.isReadOnly()) | 
|  | GVS->setReadOnly(false); | 
|  | if (!VI.isWriteOnly()) | 
|  | GVS->setWriteOnly(false); | 
|  | } | 
|  | } | 
|  | } | 
|  |  | 
|  | // Do the access attribute and DSOLocal propagation in combined index. | 
|  | // The goal of attribute propagation is internalization of readonly (RO) | 
|  | // or writeonly (WO) variables. To determine which variables are RO or WO | 
|  | // and which are not we take following steps: | 
|  | // - During analysis we speculatively assign readonly and writeonly | 
|  | //   attribute to all variables which can be internalized. When computing | 
|  | //   function summary we also assign readonly or writeonly attribute to a | 
|  | //   reference if function doesn't modify referenced variable (readonly) | 
|  | //   or doesn't read it (writeonly). | 
|  | // | 
|  | // - After computing dead symbols in combined index we do the attribute | 
|  | //   and DSOLocal propagation. During this step we: | 
|  | //   a. clear RO and WO attributes from variables which are preserved or | 
|  | //      can't be imported | 
|  | //   b. clear RO and WO attributes from variables referenced by any global | 
|  | //      variable initializer | 
|  | //   c. clear RO attribute from variable referenced by a function when | 
|  | //      reference is not readonly | 
|  | //   d. clear WO attribute from variable referenced by a function when | 
|  | //      reference is not writeonly | 
|  | //   e. clear IsDSOLocal flag in every summary if any of them is false. | 
|  | // | 
|  | //   Because of (c, d) we don't internalize variables read by function A | 
|  | //   and modified by function B. | 
|  | // | 
|  | // Internalization itself happens in the backend after import is finished | 
|  | // See internalizeGVsAfterImport. | 
|  | void ModuleSummaryIndex::propagateAttributes( | 
|  | const DenseSet<GlobalValue::GUID> &GUIDPreservedSymbols) { | 
|  | if (!PropagateAttrs) | 
|  | return; | 
|  | DenseSet<ValueInfo> MarkedNonReadWriteOnly; | 
|  | for (auto &P : *this) { | 
|  | bool IsDSOLocal = true; | 
|  | for (auto &S : P.second.SummaryList) { | 
|  | if (!isGlobalValueLive(S.get())) { | 
|  | // computeDeadSymbolsAndUpdateIndirectCalls should have marked all | 
|  | // copies live. Note that it is possible that there is a GUID collision | 
|  | // between internal symbols with the same name in different files of the | 
|  | // same name but not enough distinguishing path. Because | 
|  | // computeDeadSymbolsAndUpdateIndirectCalls should conservatively mark | 
|  | // all copies live we can assert here that all are dead if any copy is | 
|  | // dead. | 
|  | assert(llvm::none_of( | 
|  | P.second.SummaryList, | 
|  | [&](const std::unique_ptr<GlobalValueSummary> &Summary) { | 
|  | return isGlobalValueLive(Summary.get()); | 
|  | })); | 
|  | // We don't examine references from dead objects | 
|  | break; | 
|  | } | 
|  |  | 
|  | // Global variable can't be marked read/writeonly if it is not eligible | 
|  | // to import since we need to ensure that all external references get | 
|  | // a local (imported) copy. It also can't be marked read/writeonly if | 
|  | // it or any alias (since alias points to the same memory) are preserved | 
|  | // or notEligibleToImport, since either of those means there could be | 
|  | // writes (or reads in case of writeonly) that are not visible (because | 
|  | // preserved means it could have external to DSO writes or reads, and | 
|  | // notEligibleToImport means it could have writes or reads via inline | 
|  | // assembly leading it to be in the @llvm.*used). | 
|  | if (auto *GVS = dyn_cast<GlobalVarSummary>(S->getBaseObject())) | 
|  | // Here we intentionally pass S.get() not GVS, because S could be | 
|  | // an alias. We don't analyze references here, because we have to | 
|  | // know exactly if GV is readonly to do so. | 
|  | if (!canImportGlobalVar(S.get(), /* AnalyzeRefs */ false) || | 
|  | GUIDPreservedSymbols.count(P.first)) { | 
|  | GVS->setReadOnly(false); | 
|  | GVS->setWriteOnly(false); | 
|  | } | 
|  | propagateAttributesToRefs(S.get(), MarkedNonReadWriteOnly); | 
|  |  | 
|  | // If the flag from any summary is false, the GV is not DSOLocal. | 
|  | IsDSOLocal &= S->isDSOLocal(); | 
|  | } | 
|  | if (!IsDSOLocal) | 
|  | // Mark the flag in all summaries false so that we can do quick check | 
|  | // without going through the whole list. | 
|  | for (const std::unique_ptr<GlobalValueSummary> &Summary : | 
|  | P.second.SummaryList) | 
|  | Summary->setDSOLocal(false); | 
|  | } | 
|  | setWithAttributePropagation(); | 
|  | setWithDSOLocalPropagation(); | 
|  | if (llvm::AreStatisticsEnabled()) | 
|  | for (auto &P : *this) | 
|  | if (P.second.SummaryList.size()) | 
|  | if (auto *GVS = dyn_cast<GlobalVarSummary>( | 
|  | P.second.SummaryList[0]->getBaseObject())) | 
|  | if (isGlobalValueLive(GVS)) { | 
|  | if (GVS->maybeReadOnly()) | 
|  | ReadOnlyLiveGVars++; | 
|  | if (GVS->maybeWriteOnly()) | 
|  | WriteOnlyLiveGVars++; | 
|  | } | 
|  | } | 
|  |  | 
|  | bool ModuleSummaryIndex::canImportGlobalVar(const GlobalValueSummary *S, | 
|  | bool AnalyzeRefs) const { | 
|  | bool CanImportDecl; | 
|  | return canImportGlobalVar(S, AnalyzeRefs, CanImportDecl); | 
|  | } | 
|  |  | 
|  | bool ModuleSummaryIndex::canImportGlobalVar(const GlobalValueSummary *S, | 
|  | bool AnalyzeRefs, | 
|  | bool &CanImportDecl) const { | 
|  | auto HasRefsPreventingImport = [this](const GlobalVarSummary *GVS) { | 
|  | // We don't analyze GV references during attribute propagation, so | 
|  | // GV with non-trivial initializer can be marked either read or | 
|  | // write-only. | 
|  | // Importing definiton of readonly GV with non-trivial initializer | 
|  | // allows us doing some extra optimizations (like converting indirect | 
|  | // calls to direct). | 
|  | // Definition of writeonly GV with non-trivial initializer should also | 
|  | // be imported. Not doing so will result in: | 
|  | // a) GV internalization in source module (because it's writeonly) | 
|  | // b) Importing of GV declaration to destination module as a result | 
|  | //    of promotion. | 
|  | // c) Link error (external declaration with internal definition). | 
|  | // However we do not promote objects referenced by writeonly GV | 
|  | // initializer by means of converting it to 'zeroinitializer' | 
|  | return !(ImportConstantsWithRefs && GVS->isConstant()) && | 
|  | !isReadOnly(GVS) && !isWriteOnly(GVS) && GVS->refs().size(); | 
|  | }; | 
|  | auto *GVS = cast<GlobalVarSummary>(S->getBaseObject()); | 
|  |  | 
|  | const bool nonInterposable = | 
|  | !GlobalValue::isInterposableLinkage(S->linkage()); | 
|  | const bool eligibleToImport = !S->notEligibleToImport(); | 
|  |  | 
|  | // It's correct to import a global variable only when it is not interposable | 
|  | // and eligible to import. | 
|  | CanImportDecl = (nonInterposable && eligibleToImport); | 
|  |  | 
|  | // Global variable with non-trivial initializer can be imported | 
|  | // if it's readonly. This gives us extra opportunities for constant | 
|  | // folding and converting indirect calls to direct calls. We don't | 
|  | // analyze GV references during attribute propagation, because we | 
|  | // don't know yet if it is readonly or not. | 
|  | return nonInterposable && eligibleToImport && | 
|  | (!AnalyzeRefs || !HasRefsPreventingImport(GVS)); | 
|  | } | 
|  |  | 
|  | // TODO: write a graphviz dumper for SCCs (see ModuleSummaryIndex::exportToDot) | 
|  | // then delete this function and update its tests | 
|  | LLVM_DUMP_METHOD | 
|  | void ModuleSummaryIndex::dumpSCCs(raw_ostream &O) { | 
|  | for (scc_iterator<ModuleSummaryIndex *> I = | 
|  | scc_begin<ModuleSummaryIndex *>(this); | 
|  | !I.isAtEnd(); ++I) { | 
|  | O << "SCC (" << utostr(I->size()) << " node" << (I->size() == 1 ? "" : "s") | 
|  | << ") {\n"; | 
|  | for (const ValueInfo &V : *I) { | 
|  | FunctionSummary *F = nullptr; | 
|  | if (V.getSummaryList().size()) | 
|  | F = cast<FunctionSummary>(V.getSummaryList().front().get()); | 
|  | O << " " << (F == nullptr ? "External" : "") << " " << utostr(V.getGUID()) | 
|  | << (I.hasCycle() ? " (has cycle)" : "") << "\n"; | 
|  | } | 
|  | O << "}\n"; | 
|  | } | 
|  | } | 
|  |  | 
|  | namespace { | 
|  | struct Attributes { | 
|  | void add(const Twine &Name, const Twine &Value, | 
|  | const Twine &Comment = Twine()); | 
|  | void addComment(const Twine &Comment); | 
|  | std::string getAsString() const; | 
|  |  | 
|  | std::vector<std::string> Attrs; | 
|  | std::string Comments; | 
|  | }; | 
|  |  | 
|  | struct Edge { | 
|  | uint64_t SrcMod; | 
|  | int Hotness; | 
|  | GlobalValue::GUID Src; | 
|  | GlobalValue::GUID Dst; | 
|  | }; | 
|  | } | 
|  |  | 
|  | void Attributes::add(const Twine &Name, const Twine &Value, | 
|  | const Twine &Comment) { | 
|  | std::string A = Name.str(); | 
|  | A += "=\""; | 
|  | A += Value.str(); | 
|  | A += "\""; | 
|  | Attrs.push_back(A); | 
|  | addComment(Comment); | 
|  | } | 
|  |  | 
|  | void Attributes::addComment(const Twine &Comment) { | 
|  | if (!Comment.isTriviallyEmpty()) { | 
|  | if (Comments.empty()) | 
|  | Comments = " // "; | 
|  | else | 
|  | Comments += ", "; | 
|  | Comments += Comment.str(); | 
|  | } | 
|  | } | 
|  |  | 
|  | std::string Attributes::getAsString() const { | 
|  | if (Attrs.empty()) | 
|  | return ""; | 
|  |  | 
|  | std::string Ret = "["; | 
|  | for (auto &A : Attrs) | 
|  | Ret += A + ","; | 
|  | Ret.pop_back(); | 
|  | Ret += "];"; | 
|  | Ret += Comments; | 
|  | return Ret; | 
|  | } | 
|  |  | 
|  | static std::string linkageToString(GlobalValue::LinkageTypes LT) { | 
|  | switch (LT) { | 
|  | case GlobalValue::ExternalLinkage: | 
|  | return "extern"; | 
|  | case GlobalValue::AvailableExternallyLinkage: | 
|  | return "av_ext"; | 
|  | case GlobalValue::LinkOnceAnyLinkage: | 
|  | return "linkonce"; | 
|  | case GlobalValue::LinkOnceODRLinkage: | 
|  | return "linkonce_odr"; | 
|  | case GlobalValue::WeakAnyLinkage: | 
|  | return "weak"; | 
|  | case GlobalValue::WeakODRLinkage: | 
|  | return "weak_odr"; | 
|  | case GlobalValue::AppendingLinkage: | 
|  | return "appending"; | 
|  | case GlobalValue::InternalLinkage: | 
|  | return "internal"; | 
|  | case GlobalValue::PrivateLinkage: | 
|  | return "private"; | 
|  | case GlobalValue::ExternalWeakLinkage: | 
|  | return "extern_weak"; | 
|  | case GlobalValue::CommonLinkage: | 
|  | return "common"; | 
|  | } | 
|  |  | 
|  | return "<unknown>"; | 
|  | } | 
|  |  | 
|  | static std::string fflagsToString(FunctionSummary::FFlags F) { | 
|  | auto FlagValue = [](unsigned V) { return V ? '1' : '0'; }; | 
|  | char FlagRep[] = {FlagValue(F.ReadNone), | 
|  | FlagValue(F.ReadOnly), | 
|  | FlagValue(F.NoRecurse), | 
|  | FlagValue(F.ReturnDoesNotAlias), | 
|  | FlagValue(F.NoInline), | 
|  | FlagValue(F.AlwaysInline), | 
|  | FlagValue(F.NoUnwind), | 
|  | FlagValue(F.MayThrow), | 
|  | FlagValue(F.HasUnknownCall), | 
|  | FlagValue(F.MustBeUnreachable), | 
|  | 0}; | 
|  |  | 
|  | return FlagRep; | 
|  | } | 
|  |  | 
|  | // Get string representation of function instruction count and flags. | 
|  | static std::string getSummaryAttributes(GlobalValueSummary* GVS) { | 
|  | auto *FS = dyn_cast_or_null<FunctionSummary>(GVS); | 
|  | if (!FS) | 
|  | return ""; | 
|  |  | 
|  | return std::string("inst: ") + std::to_string(FS->instCount()) + | 
|  | ", ffl: " + fflagsToString(FS->fflags()); | 
|  | } | 
|  |  | 
|  | static std::string getNodeVisualName(GlobalValue::GUID Id) { | 
|  | return std::string("@") + std::to_string(Id); | 
|  | } | 
|  |  | 
|  | static std::string getNodeVisualName(const ValueInfo &VI) { | 
|  | return VI.name().empty() ? getNodeVisualName(VI.getGUID()) : VI.name().str(); | 
|  | } | 
|  |  | 
|  | static std::string getNodeLabel(const ValueInfo &VI, GlobalValueSummary *GVS) { | 
|  | if (isa<AliasSummary>(GVS)) | 
|  | return getNodeVisualName(VI); | 
|  |  | 
|  | std::string Attrs = getSummaryAttributes(GVS); | 
|  | std::string Label = | 
|  | getNodeVisualName(VI) + "|" + linkageToString(GVS->linkage()); | 
|  | if (!Attrs.empty()) | 
|  | Label += std::string(" (") + Attrs + ")"; | 
|  | Label += "}"; | 
|  |  | 
|  | return Label; | 
|  | } | 
|  |  | 
|  | // Write definition of external node, which doesn't have any | 
|  | // specific module associated with it. Typically this is function | 
|  | // or variable defined in native object or library. | 
|  | static void defineExternalNode(raw_ostream &OS, const char *Pfx, | 
|  | const ValueInfo &VI, GlobalValue::GUID Id) { | 
|  | auto StrId = std::to_string(Id); | 
|  | OS << "  " << StrId << " [label=\""; | 
|  |  | 
|  | if (VI) { | 
|  | OS << getNodeVisualName(VI); | 
|  | } else { | 
|  | OS << getNodeVisualName(Id); | 
|  | } | 
|  | OS << "\"]; // defined externally\n"; | 
|  | } | 
|  |  | 
|  | static bool hasReadOnlyFlag(const GlobalValueSummary *S) { | 
|  | if (auto *GVS = dyn_cast<GlobalVarSummary>(S)) | 
|  | return GVS->maybeReadOnly(); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | static bool hasWriteOnlyFlag(const GlobalValueSummary *S) { | 
|  | if (auto *GVS = dyn_cast<GlobalVarSummary>(S)) | 
|  | return GVS->maybeWriteOnly(); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | static bool hasConstantFlag(const GlobalValueSummary *S) { | 
|  | if (auto *GVS = dyn_cast<GlobalVarSummary>(S)) | 
|  | return GVS->isConstant(); | 
|  | return false; | 
|  | } | 
|  |  | 
|  | void ModuleSummaryIndex::exportToDot( | 
|  | raw_ostream &OS, | 
|  | const DenseSet<GlobalValue::GUID> &GUIDPreservedSymbols) const { | 
|  | std::vector<Edge> CrossModuleEdges; | 
|  | DenseMap<GlobalValue::GUID, std::vector<uint64_t>> NodeMap; | 
|  | using GVSOrderedMapTy = std::map<GlobalValue::GUID, GlobalValueSummary *>; | 
|  | std::map<StringRef, GVSOrderedMapTy> ModuleToDefinedGVS; | 
|  | collectDefinedGVSummariesPerModule(ModuleToDefinedGVS); | 
|  |  | 
|  | // Assign an id to each module path for use in graph labels. Since the | 
|  | // StringMap iteration order isn't guaranteed, order by path string before | 
|  | // assigning ids. | 
|  | std::vector<StringRef> ModulePaths; | 
|  | for (auto &[ModPath, _] : modulePaths()) | 
|  | ModulePaths.push_back(ModPath); | 
|  | llvm::sort(ModulePaths); | 
|  | DenseMap<StringRef, uint64_t> ModuleIdMap; | 
|  | for (auto &ModPath : ModulePaths) | 
|  | ModuleIdMap.try_emplace(ModPath, ModuleIdMap.size()); | 
|  |  | 
|  | // Get node identifier in form MXXX_<GUID>. The MXXX prefix is required, | 
|  | // because we may have multiple linkonce functions summaries. | 
|  | auto NodeId = [](uint64_t ModId, GlobalValue::GUID Id) { | 
|  | return ModId == (uint64_t)-1 ? std::to_string(Id) | 
|  | : std::string("M") + std::to_string(ModId) + | 
|  | "_" + std::to_string(Id); | 
|  | }; | 
|  |  | 
|  | auto DrawEdge = [&](const char *Pfx, uint64_t SrcMod, GlobalValue::GUID SrcId, | 
|  | uint64_t DstMod, GlobalValue::GUID DstId, | 
|  | int TypeOrHotness) { | 
|  | // 0 - alias | 
|  | // 1 - reference | 
|  | // 2 - constant reference | 
|  | // 3 - writeonly reference | 
|  | // Other value: (hotness - 4). | 
|  | TypeOrHotness += 4; | 
|  | static const char *EdgeAttrs[] = { | 
|  | " [style=dotted]; // alias", | 
|  | " [style=dashed]; // ref", | 
|  | " [style=dashed,color=forestgreen]; // const-ref", | 
|  | " [style=dashed,color=violetred]; // writeOnly-ref", | 
|  | " // call (hotness : Unknown)", | 
|  | " [color=blue]; // call (hotness : Cold)", | 
|  | " // call (hotness : None)", | 
|  | " [color=brown]; // call (hotness : Hot)", | 
|  | " [style=bold,color=red]; // call (hotness : Critical)"}; | 
|  |  | 
|  | assert(static_cast<size_t>(TypeOrHotness) < std::size(EdgeAttrs)); | 
|  | OS << Pfx << NodeId(SrcMod, SrcId) << " -> " << NodeId(DstMod, DstId) | 
|  | << EdgeAttrs[TypeOrHotness] << "\n"; | 
|  | }; | 
|  |  | 
|  | OS << "digraph Summary {\n"; | 
|  | for (auto &ModIt : ModuleToDefinedGVS) { | 
|  | // Will be empty for a just built per-module index, which doesn't setup a | 
|  | // module paths table. In that case use 0 as the module id. | 
|  | assert(ModuleIdMap.count(ModIt.first) || ModuleIdMap.empty()); | 
|  | auto ModId = ModuleIdMap.empty() ? 0 : ModuleIdMap[ModIt.first]; | 
|  | OS << "  // Module: " << ModIt.first << "\n"; | 
|  | OS << "  subgraph cluster_" << std::to_string(ModId) << " {\n"; | 
|  | OS << "    style = filled;\n"; | 
|  | OS << "    color = lightgrey;\n"; | 
|  | OS << "    label = \"" << sys::path::filename(ModIt.first) << "\";\n"; | 
|  | OS << "    node [style=filled,fillcolor=lightblue];\n"; | 
|  |  | 
|  | auto &GVSMap = ModIt.second; | 
|  | auto Draw = [&](GlobalValue::GUID IdFrom, GlobalValue::GUID IdTo, int Hotness) { | 
|  | if (!GVSMap.count(IdTo)) { | 
|  | CrossModuleEdges.push_back({ModId, Hotness, IdFrom, IdTo}); | 
|  | return; | 
|  | } | 
|  | DrawEdge("    ", ModId, IdFrom, ModId, IdTo, Hotness); | 
|  | }; | 
|  |  | 
|  | for (auto &SummaryIt : GVSMap) { | 
|  | NodeMap[SummaryIt.first].push_back(ModId); | 
|  | auto Flags = SummaryIt.second->flags(); | 
|  | Attributes A; | 
|  | if (isa<FunctionSummary>(SummaryIt.second)) { | 
|  | A.add("shape", "record", "function"); | 
|  | } else if (isa<AliasSummary>(SummaryIt.second)) { | 
|  | A.add("style", "dotted,filled", "alias"); | 
|  | A.add("shape", "box"); | 
|  | } else { | 
|  | A.add("shape", "Mrecord", "variable"); | 
|  | if (Flags.Live && hasReadOnlyFlag(SummaryIt.second)) | 
|  | A.addComment("immutable"); | 
|  | if (Flags.Live && hasWriteOnlyFlag(SummaryIt.second)) | 
|  | A.addComment("writeOnly"); | 
|  | if (Flags.Live && hasConstantFlag(SummaryIt.second)) | 
|  | A.addComment("constant"); | 
|  | } | 
|  | if (Flags.Visibility) | 
|  | A.addComment("visibility"); | 
|  | if (Flags.DSOLocal) | 
|  | A.addComment("dsoLocal"); | 
|  | if (Flags.CanAutoHide) | 
|  | A.addComment("canAutoHide"); | 
|  | if (Flags.ImportType == GlobalValueSummary::ImportKind::Definition) | 
|  | A.addComment("definition"); | 
|  | else if (Flags.ImportType == GlobalValueSummary::ImportKind::Declaration) | 
|  | A.addComment("declaration"); | 
|  | if (GUIDPreservedSymbols.count(SummaryIt.first)) | 
|  | A.addComment("preserved"); | 
|  |  | 
|  | auto VI = getValueInfo(SummaryIt.first); | 
|  | A.add("label", getNodeLabel(VI, SummaryIt.second)); | 
|  | if (!Flags.Live) | 
|  | A.add("fillcolor", "red", "dead"); | 
|  | else if (Flags.NotEligibleToImport) | 
|  | A.add("fillcolor", "yellow", "not eligible to import"); | 
|  |  | 
|  | OS << "    " << NodeId(ModId, SummaryIt.first) << " " << A.getAsString() | 
|  | << "\n"; | 
|  | } | 
|  | OS << "    // Edges:\n"; | 
|  |  | 
|  | for (auto &SummaryIt : GVSMap) { | 
|  | auto *GVS = SummaryIt.second; | 
|  | for (auto &R : GVS->refs()) | 
|  | Draw(SummaryIt.first, R.getGUID(), | 
|  | R.isWriteOnly() ? -1 : (R.isReadOnly() ? -2 : -3)); | 
|  |  | 
|  | if (auto *AS = dyn_cast_or_null<AliasSummary>(SummaryIt.second)) { | 
|  | Draw(SummaryIt.first, AS->getAliaseeGUID(), -4); | 
|  | continue; | 
|  | } | 
|  |  | 
|  | if (auto *FS = dyn_cast_or_null<FunctionSummary>(SummaryIt.second)) | 
|  | for (auto &CGEdge : FS->calls()) | 
|  | Draw(SummaryIt.first, CGEdge.first.getGUID(), | 
|  | static_cast<int>(CGEdge.second.Hotness)); | 
|  | } | 
|  | OS << "  }\n"; | 
|  | } | 
|  |  | 
|  | OS << "  // Cross-module edges:\n"; | 
|  | for (auto &E : CrossModuleEdges) { | 
|  | auto &ModList = NodeMap[E.Dst]; | 
|  | if (ModList.empty()) { | 
|  | defineExternalNode(OS, "  ", getValueInfo(E.Dst), E.Dst); | 
|  | // Add fake module to the list to draw an edge to an external node | 
|  | // in the loop below. | 
|  | ModList.push_back(-1); | 
|  | } | 
|  | for (auto DstMod : ModList) | 
|  | // The edge representing call or ref is drawn to every module where target | 
|  | // symbol is defined. When target is a linkonce symbol there can be | 
|  | // multiple edges representing a single call or ref, both intra-module and | 
|  | // cross-module. As we've already drawn all intra-module edges before we | 
|  | // skip it here. | 
|  | if (DstMod != E.SrcMod) | 
|  | DrawEdge("  ", E.SrcMod, E.Src, DstMod, E.Dst, E.Hotness); | 
|  | } | 
|  |  | 
|  | OS << "}"; | 
|  | } |