| //===- lib/Linker/IRMover.cpp ---------------------------------------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/Linker/IRMover.h" |
| #include "LinkDiagnosticInfo.h" |
| #include "llvm/ADT/SetVector.h" |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/ADT/Triple.h" |
| #include "llvm/IR/Constants.h" |
| #include "llvm/IR/DebugInfo.h" |
| #include "llvm/IR/DiagnosticPrinter.h" |
| #include "llvm/IR/GVMaterializer.h" |
| #include "llvm/IR/Intrinsics.h" |
| #include "llvm/IR/PseudoProbe.h" |
| #include "llvm/IR/TypeFinder.h" |
| #include "llvm/Object/ModuleSymbolTable.h" |
| #include "llvm/Support/Error.h" |
| #include "llvm/Support/Path.h" |
| #include "llvm/Transforms/Utils/Cloning.h" |
| #include <utility> |
| using namespace llvm; |
| |
| //===----------------------------------------------------------------------===// |
| // TypeMap implementation. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| class TypeMapTy : public ValueMapTypeRemapper { |
| /// This is a mapping from a source type to a destination type to use. |
| DenseMap<Type *, Type *> MappedTypes; |
| |
| /// When checking to see if two subgraphs are isomorphic, we speculatively |
| /// add types to MappedTypes, but keep track of them here in case we need to |
| /// roll back. |
| SmallVector<Type *, 16> SpeculativeTypes; |
| |
| SmallVector<StructType *, 16> SpeculativeDstOpaqueTypes; |
| |
| /// This is a list of non-opaque structs in the source module that are mapped |
| /// to an opaque struct in the destination module. |
| SmallVector<StructType *, 16> SrcDefinitionsToResolve; |
| |
| /// This is the set of opaque types in the destination modules who are |
| /// getting a body from the source module. |
| SmallPtrSet<StructType *, 16> DstResolvedOpaqueTypes; |
| |
| public: |
| TypeMapTy(IRMover::IdentifiedStructTypeSet &DstStructTypesSet) |
| : DstStructTypesSet(DstStructTypesSet) {} |
| |
| IRMover::IdentifiedStructTypeSet &DstStructTypesSet; |
| /// Indicate that the specified type in the destination module is conceptually |
| /// equivalent to the specified type in the source module. |
| void addTypeMapping(Type *DstTy, Type *SrcTy); |
| |
| /// Produce a body for an opaque type in the dest module from a type |
| /// definition in the source module. |
| void linkDefinedTypeBodies(); |
| |
| /// Return the mapped type to use for the specified input type from the |
| /// source module. |
| Type *get(Type *SrcTy); |
| Type *get(Type *SrcTy, SmallPtrSet<StructType *, 8> &Visited); |
| |
| void finishType(StructType *DTy, StructType *STy, ArrayRef<Type *> ETypes); |
| |
| FunctionType *get(FunctionType *T) { |
| return cast<FunctionType>(get((Type *)T)); |
| } |
| |
| private: |
| Type *remapType(Type *SrcTy) override { return get(SrcTy); } |
| |
| bool areTypesIsomorphic(Type *DstTy, Type *SrcTy); |
| }; |
| } |
| |
| void TypeMapTy::addTypeMapping(Type *DstTy, Type *SrcTy) { |
| assert(SpeculativeTypes.empty()); |
| assert(SpeculativeDstOpaqueTypes.empty()); |
| |
| // Check to see if these types are recursively isomorphic and establish a |
| // mapping between them if so. |
| if (!areTypesIsomorphic(DstTy, SrcTy)) { |
| // Oops, they aren't isomorphic. Just discard this request by rolling out |
| // any speculative mappings we've established. |
| for (Type *Ty : SpeculativeTypes) |
| MappedTypes.erase(Ty); |
| |
| SrcDefinitionsToResolve.resize(SrcDefinitionsToResolve.size() - |
| SpeculativeDstOpaqueTypes.size()); |
| for (StructType *Ty : SpeculativeDstOpaqueTypes) |
| DstResolvedOpaqueTypes.erase(Ty); |
| } else { |
| // SrcTy and DstTy are recursively ismorphic. We clear names of SrcTy |
| // and all its descendants to lower amount of renaming in LLVM context |
| // Renaming occurs because we load all source modules to the same context |
| // and declaration with existing name gets renamed (i.e Foo -> Foo.42). |
| // As a result we may get several different types in the destination |
| // module, which are in fact the same. |
| for (Type *Ty : SpeculativeTypes) |
| if (auto *STy = dyn_cast<StructType>(Ty)) |
| if (STy->hasName()) |
| STy->setName(""); |
| } |
| SpeculativeTypes.clear(); |
| SpeculativeDstOpaqueTypes.clear(); |
| } |
| |
| /// Recursively walk this pair of types, returning true if they are isomorphic, |
| /// false if they are not. |
| bool TypeMapTy::areTypesIsomorphic(Type *DstTy, Type *SrcTy) { |
| // Two types with differing kinds are clearly not isomorphic. |
| if (DstTy->getTypeID() != SrcTy->getTypeID()) |
| return false; |
| |
| // If we have an entry in the MappedTypes table, then we have our answer. |
| Type *&Entry = MappedTypes[SrcTy]; |
| if (Entry) |
| return Entry == DstTy; |
| |
| // Two identical types are clearly isomorphic. Remember this |
| // non-speculatively. |
| if (DstTy == SrcTy) { |
| Entry = DstTy; |
| return true; |
| } |
| |
| // Okay, we have two types with identical kinds that we haven't seen before. |
| |
| // If this is an opaque struct type, special case it. |
| if (StructType *SSTy = dyn_cast<StructType>(SrcTy)) { |
| // Mapping an opaque type to any struct, just keep the dest struct. |
| if (SSTy->isOpaque()) { |
| Entry = DstTy; |
| SpeculativeTypes.push_back(SrcTy); |
| return true; |
| } |
| |
| // Mapping a non-opaque source type to an opaque dest. If this is the first |
| // type that we're mapping onto this destination type then we succeed. Keep |
| // the dest, but fill it in later. If this is the second (different) type |
| // that we're trying to map onto the same opaque type then we fail. |
| if (cast<StructType>(DstTy)->isOpaque()) { |
| // We can only map one source type onto the opaque destination type. |
| if (!DstResolvedOpaqueTypes.insert(cast<StructType>(DstTy)).second) |
| return false; |
| SrcDefinitionsToResolve.push_back(SSTy); |
| SpeculativeTypes.push_back(SrcTy); |
| SpeculativeDstOpaqueTypes.push_back(cast<StructType>(DstTy)); |
| Entry = DstTy; |
| return true; |
| } |
| } |
| |
| // If the number of subtypes disagree between the two types, then we fail. |
| if (SrcTy->getNumContainedTypes() != DstTy->getNumContainedTypes()) |
| return false; |
| |
| // Fail if any of the extra properties (e.g. array size) of the type disagree. |
| if (isa<IntegerType>(DstTy)) |
| return false; // bitwidth disagrees. |
| if (PointerType *PT = dyn_cast<PointerType>(DstTy)) { |
| if (PT->getAddressSpace() != cast<PointerType>(SrcTy)->getAddressSpace()) |
| return false; |
| } else if (FunctionType *FT = dyn_cast<FunctionType>(DstTy)) { |
| if (FT->isVarArg() != cast<FunctionType>(SrcTy)->isVarArg()) |
| return false; |
| } else if (StructType *DSTy = dyn_cast<StructType>(DstTy)) { |
| StructType *SSTy = cast<StructType>(SrcTy); |
| if (DSTy->isLiteral() != SSTy->isLiteral() || |
| DSTy->isPacked() != SSTy->isPacked()) |
| return false; |
| } else if (auto *DArrTy = dyn_cast<ArrayType>(DstTy)) { |
| if (DArrTy->getNumElements() != cast<ArrayType>(SrcTy)->getNumElements()) |
| return false; |
| } else if (auto *DVecTy = dyn_cast<VectorType>(DstTy)) { |
| if (DVecTy->getElementCount() != cast<VectorType>(SrcTy)->getElementCount()) |
| return false; |
| } |
| |
| // Otherwise, we speculate that these two types will line up and recursively |
| // check the subelements. |
| Entry = DstTy; |
| SpeculativeTypes.push_back(SrcTy); |
| |
| for (unsigned I = 0, E = SrcTy->getNumContainedTypes(); I != E; ++I) |
| if (!areTypesIsomorphic(DstTy->getContainedType(I), |
| SrcTy->getContainedType(I))) |
| return false; |
| |
| // If everything seems to have lined up, then everything is great. |
| return true; |
| } |
| |
| void TypeMapTy::linkDefinedTypeBodies() { |
| SmallVector<Type *, 16> Elements; |
| for (StructType *SrcSTy : SrcDefinitionsToResolve) { |
| StructType *DstSTy = cast<StructType>(MappedTypes[SrcSTy]); |
| assert(DstSTy->isOpaque()); |
| |
| // Map the body of the source type over to a new body for the dest type. |
| Elements.resize(SrcSTy->getNumElements()); |
| for (unsigned I = 0, E = Elements.size(); I != E; ++I) |
| Elements[I] = get(SrcSTy->getElementType(I)); |
| |
| DstSTy->setBody(Elements, SrcSTy->isPacked()); |
| DstStructTypesSet.switchToNonOpaque(DstSTy); |
| } |
| SrcDefinitionsToResolve.clear(); |
| DstResolvedOpaqueTypes.clear(); |
| } |
| |
| void TypeMapTy::finishType(StructType *DTy, StructType *STy, |
| ArrayRef<Type *> ETypes) { |
| DTy->setBody(ETypes, STy->isPacked()); |
| |
| // Steal STy's name. |
| if (STy->hasName()) { |
| SmallString<16> TmpName = STy->getName(); |
| STy->setName(""); |
| DTy->setName(TmpName); |
| } |
| |
| DstStructTypesSet.addNonOpaque(DTy); |
| } |
| |
| Type *TypeMapTy::get(Type *Ty) { |
| SmallPtrSet<StructType *, 8> Visited; |
| return get(Ty, Visited); |
| } |
| |
| Type *TypeMapTy::get(Type *Ty, SmallPtrSet<StructType *, 8> &Visited) { |
| // If we already have an entry for this type, return it. |
| Type **Entry = &MappedTypes[Ty]; |
| if (*Entry) |
| return *Entry; |
| |
| // These are types that LLVM itself will unique. |
| bool IsUniqued = !isa<StructType>(Ty) || cast<StructType>(Ty)->isLiteral(); |
| |
| if (!IsUniqued) { |
| #ifndef NDEBUG |
| for (auto &Pair : MappedTypes) { |
| assert(!(Pair.first != Ty && Pair.second == Ty) && |
| "mapping to a source type"); |
| } |
| #endif |
| |
| if (!Visited.insert(cast<StructType>(Ty)).second) { |
| StructType *DTy = StructType::create(Ty->getContext()); |
| return *Entry = DTy; |
| } |
| } |
| |
| // If this is not a recursive type, then just map all of the elements and |
| // then rebuild the type from inside out. |
| SmallVector<Type *, 4> ElementTypes; |
| |
| // If there are no element types to map, then the type is itself. This is |
| // true for the anonymous {} struct, things like 'float', integers, etc. |
| if (Ty->getNumContainedTypes() == 0 && IsUniqued) |
| return *Entry = Ty; |
| |
| // Remap all of the elements, keeping track of whether any of them change. |
| bool AnyChange = false; |
| ElementTypes.resize(Ty->getNumContainedTypes()); |
| for (unsigned I = 0, E = Ty->getNumContainedTypes(); I != E; ++I) { |
| ElementTypes[I] = get(Ty->getContainedType(I), Visited); |
| AnyChange |= ElementTypes[I] != Ty->getContainedType(I); |
| } |
| |
| // If we found our type while recursively processing stuff, just use it. |
| Entry = &MappedTypes[Ty]; |
| if (*Entry) { |
| if (auto *DTy = dyn_cast<StructType>(*Entry)) { |
| if (DTy->isOpaque()) { |
| auto *STy = cast<StructType>(Ty); |
| finishType(DTy, STy, ElementTypes); |
| } |
| } |
| return *Entry; |
| } |
| |
| // If all of the element types mapped directly over and the type is not |
| // a named struct, then the type is usable as-is. |
| if (!AnyChange && IsUniqued) |
| return *Entry = Ty; |
| |
| // Otherwise, rebuild a modified type. |
| switch (Ty->getTypeID()) { |
| default: |
| llvm_unreachable("unknown derived type to remap"); |
| case Type::ArrayTyID: |
| return *Entry = ArrayType::get(ElementTypes[0], |
| cast<ArrayType>(Ty)->getNumElements()); |
| case Type::ScalableVectorTyID: |
| case Type::FixedVectorTyID: |
| return *Entry = VectorType::get(ElementTypes[0], |
| cast<VectorType>(Ty)->getElementCount()); |
| case Type::PointerTyID: |
| return *Entry = PointerType::get(ElementTypes[0], |
| cast<PointerType>(Ty)->getAddressSpace()); |
| case Type::FunctionTyID: |
| return *Entry = FunctionType::get(ElementTypes[0], |
| makeArrayRef(ElementTypes).slice(1), |
| cast<FunctionType>(Ty)->isVarArg()); |
| case Type::StructTyID: { |
| auto *STy = cast<StructType>(Ty); |
| bool IsPacked = STy->isPacked(); |
| if (IsUniqued) |
| return *Entry = StructType::get(Ty->getContext(), ElementTypes, IsPacked); |
| |
| // If the type is opaque, we can just use it directly. |
| if (STy->isOpaque()) { |
| DstStructTypesSet.addOpaque(STy); |
| return *Entry = Ty; |
| } |
| |
| if (StructType *OldT = |
| DstStructTypesSet.findNonOpaque(ElementTypes, IsPacked)) { |
| STy->setName(""); |
| return *Entry = OldT; |
| } |
| |
| if (!AnyChange) { |
| DstStructTypesSet.addNonOpaque(STy); |
| return *Entry = Ty; |
| } |
| |
| StructType *DTy = StructType::create(Ty->getContext()); |
| finishType(DTy, STy, ElementTypes); |
| return *Entry = DTy; |
| } |
| } |
| } |
| |
| LinkDiagnosticInfo::LinkDiagnosticInfo(DiagnosticSeverity Severity, |
| const Twine &Msg) |
| : DiagnosticInfo(DK_Linker, Severity), Msg(Msg) {} |
| void LinkDiagnosticInfo::print(DiagnosticPrinter &DP) const { DP << Msg; } |
| |
| //===----------------------------------------------------------------------===// |
| // IRLinker implementation. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| class IRLinker; |
| |
| /// Creates prototypes for functions that are lazily linked on the fly. This |
| /// speeds up linking for modules with many/ lazily linked functions of which |
| /// few get used. |
| class GlobalValueMaterializer final : public ValueMaterializer { |
| IRLinker &TheIRLinker; |
| |
| public: |
| GlobalValueMaterializer(IRLinker &TheIRLinker) : TheIRLinker(TheIRLinker) {} |
| Value *materialize(Value *V) override; |
| }; |
| |
| class LocalValueMaterializer final : public ValueMaterializer { |
| IRLinker &TheIRLinker; |
| |
| public: |
| LocalValueMaterializer(IRLinker &TheIRLinker) : TheIRLinker(TheIRLinker) {} |
| Value *materialize(Value *V) override; |
| }; |
| |
| /// Type of the Metadata map in \a ValueToValueMapTy. |
| typedef DenseMap<const Metadata *, TrackingMDRef> MDMapT; |
| |
| /// This is responsible for keeping track of the state used for moving data |
| /// from SrcM to DstM. |
| class IRLinker { |
| Module &DstM; |
| std::unique_ptr<Module> SrcM; |
| |
| /// See IRMover::move(). |
| std::function<void(GlobalValue &, IRMover::ValueAdder)> AddLazyFor; |
| |
| TypeMapTy TypeMap; |
| GlobalValueMaterializer GValMaterializer; |
| LocalValueMaterializer LValMaterializer; |
| |
| /// A metadata map that's shared between IRLinker instances. |
| MDMapT &SharedMDs; |
| |
| /// Mapping of values from what they used to be in Src, to what they are now |
| /// in DstM. ValueToValueMapTy is a ValueMap, which involves some overhead |
| /// due to the use of Value handles which the Linker doesn't actually need, |
| /// but this allows us to reuse the ValueMapper code. |
| ValueToValueMapTy ValueMap; |
| ValueToValueMapTy IndirectSymbolValueMap; |
| |
| DenseSet<GlobalValue *> ValuesToLink; |
| std::vector<GlobalValue *> Worklist; |
| std::vector<std::pair<GlobalValue *, Value*>> RAUWWorklist; |
| |
| void maybeAdd(GlobalValue *GV) { |
| if (ValuesToLink.insert(GV).second) |
| Worklist.push_back(GV); |
| } |
| |
| /// Whether we are importing globals for ThinLTO, as opposed to linking the |
| /// source module. If this flag is set, it means that we can rely on some |
| /// other object file to define any non-GlobalValue entities defined by the |
| /// source module. This currently causes us to not link retained types in |
| /// debug info metadata and module inline asm. |
| bool IsPerformingImport; |
| |
| /// Set to true when all global value body linking is complete (including |
| /// lazy linking). Used to prevent metadata linking from creating new |
| /// references. |
| bool DoneLinkingBodies = false; |
| |
| /// The Error encountered during materialization. We use an Optional here to |
| /// avoid needing to manage an unconsumed success value. |
| Optional<Error> FoundError; |
| void setError(Error E) { |
| if (E) |
| FoundError = std::move(E); |
| } |
| |
| /// Most of the errors produced by this module are inconvertible StringErrors. |
| /// This convenience function lets us return one of those more easily. |
| Error stringErr(const Twine &T) { |
| return make_error<StringError>(T, inconvertibleErrorCode()); |
| } |
| |
| /// Entry point for mapping values and alternate context for mapping aliases. |
| ValueMapper Mapper; |
| unsigned IndirectSymbolMCID; |
| |
| /// Handles cloning of a global values from the source module into |
| /// the destination module, including setting the attributes and visibility. |
| GlobalValue *copyGlobalValueProto(const GlobalValue *SGV, bool ForDefinition); |
| |
| void emitWarning(const Twine &Message) { |
| SrcM->getContext().diagnose(LinkDiagnosticInfo(DS_Warning, Message)); |
| } |
| |
| /// Given a global in the source module, return the global in the |
| /// destination module that is being linked to, if any. |
| GlobalValue *getLinkedToGlobal(const GlobalValue *SrcGV) { |
| // If the source has no name it can't link. If it has local linkage, |
| // there is no name match-up going on. |
| if (!SrcGV->hasName() || SrcGV->hasLocalLinkage()) |
| return nullptr; |
| |
| // Otherwise see if we have a match in the destination module's symtab. |
| GlobalValue *DGV = DstM.getNamedValue(SrcGV->getName()); |
| if (!DGV) |
| return nullptr; |
| |
| // If we found a global with the same name in the dest module, but it has |
| // internal linkage, we are really not doing any linkage here. |
| if (DGV->hasLocalLinkage()) |
| return nullptr; |
| |
| // If we found an intrinsic declaration with mismatching prototypes, we |
| // probably had a nameclash. Don't use that version. |
| if (auto *FDGV = dyn_cast<Function>(DGV)) |
| if (FDGV->isIntrinsic()) |
| if (const auto *FSrcGV = dyn_cast<Function>(SrcGV)) |
| if (FDGV->getFunctionType() != TypeMap.get(FSrcGV->getFunctionType())) |
| return nullptr; |
| |
| // Otherwise, we do in fact link to the destination global. |
| return DGV; |
| } |
| |
| void computeTypeMapping(); |
| |
| Expected<Constant *> linkAppendingVarProto(GlobalVariable *DstGV, |
| const GlobalVariable *SrcGV); |
| |
| /// Given the GlobaValue \p SGV in the source module, and the matching |
| /// GlobalValue \p DGV (if any), return true if the linker will pull \p SGV |
| /// into the destination module. |
| /// |
| /// Note this code may call the client-provided \p AddLazyFor. |
| bool shouldLink(GlobalValue *DGV, GlobalValue &SGV); |
| Expected<Constant *> linkGlobalValueProto(GlobalValue *GV, |
| bool ForIndirectSymbol); |
| |
| Error linkModuleFlagsMetadata(); |
| |
| void linkGlobalVariable(GlobalVariable &Dst, GlobalVariable &Src); |
| Error linkFunctionBody(Function &Dst, Function &Src); |
| void linkAliasAliasee(GlobalAlias &Dst, GlobalAlias &Src); |
| void linkIFuncResolver(GlobalIFunc &Dst, GlobalIFunc &Src); |
| Error linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src); |
| |
| /// Replace all types in the source AttributeList with the |
| /// corresponding destination type. |
| AttributeList mapAttributeTypes(LLVMContext &C, AttributeList Attrs); |
| |
| /// Functions that take care of cloning a specific global value type |
| /// into the destination module. |
| GlobalVariable *copyGlobalVariableProto(const GlobalVariable *SGVar); |
| Function *copyFunctionProto(const Function *SF); |
| GlobalValue *copyIndirectSymbolProto(const GlobalValue *SGV); |
| |
| /// Perform "replace all uses with" operations. These work items need to be |
| /// performed as part of materialization, but we postpone them to happen after |
| /// materialization is done. The materializer called by ValueMapper is not |
| /// expected to delete constants, as ValueMapper is holding pointers to some |
| /// of them, but constant destruction may be indirectly triggered by RAUW. |
| /// Hence, the need to move this out of the materialization call chain. |
| void flushRAUWWorklist(); |
| |
| /// When importing for ThinLTO, prevent importing of types listed on |
| /// the DICompileUnit that we don't need a copy of in the importing |
| /// module. |
| void prepareCompileUnitsForImport(); |
| void linkNamedMDNodes(); |
| |
| public: |
| IRLinker(Module &DstM, MDMapT &SharedMDs, |
| IRMover::IdentifiedStructTypeSet &Set, std::unique_ptr<Module> SrcM, |
| ArrayRef<GlobalValue *> ValuesToLink, |
| std::function<void(GlobalValue &, IRMover::ValueAdder)> AddLazyFor, |
| bool IsPerformingImport) |
| : DstM(DstM), SrcM(std::move(SrcM)), AddLazyFor(std::move(AddLazyFor)), |
| TypeMap(Set), GValMaterializer(*this), LValMaterializer(*this), |
| SharedMDs(SharedMDs), IsPerformingImport(IsPerformingImport), |
| Mapper(ValueMap, RF_ReuseAndMutateDistinctMDs | RF_IgnoreMissingLocals, |
| &TypeMap, &GValMaterializer), |
| IndirectSymbolMCID(Mapper.registerAlternateMappingContext( |
| IndirectSymbolValueMap, &LValMaterializer)) { |
| ValueMap.getMDMap() = std::move(SharedMDs); |
| for (GlobalValue *GV : ValuesToLink) |
| maybeAdd(GV); |
| if (IsPerformingImport) |
| prepareCompileUnitsForImport(); |
| } |
| ~IRLinker() { SharedMDs = std::move(*ValueMap.getMDMap()); } |
| |
| Error run(); |
| Value *materialize(Value *V, bool ForIndirectSymbol); |
| }; |
| } |
| |
| /// The LLVM SymbolTable class autorenames globals that conflict in the symbol |
| /// table. This is good for all clients except for us. Go through the trouble |
| /// to force this back. |
| static void forceRenaming(GlobalValue *GV, StringRef Name) { |
| // If the global doesn't force its name or if it already has the right name, |
| // there is nothing for us to do. |
| if (GV->hasLocalLinkage() || GV->getName() == Name) |
| return; |
| |
| Module *M = GV->getParent(); |
| |
| // If there is a conflict, rename the conflict. |
| if (GlobalValue *ConflictGV = M->getNamedValue(Name)) { |
| GV->takeName(ConflictGV); |
| ConflictGV->setName(Name); // This will cause ConflictGV to get renamed |
| assert(ConflictGV->getName() != Name && "forceRenaming didn't work"); |
| } else { |
| GV->setName(Name); // Force the name back |
| } |
| } |
| |
| Value *GlobalValueMaterializer::materialize(Value *SGV) { |
| return TheIRLinker.materialize(SGV, false); |
| } |
| |
| Value *LocalValueMaterializer::materialize(Value *SGV) { |
| return TheIRLinker.materialize(SGV, true); |
| } |
| |
| Value *IRLinker::materialize(Value *V, bool ForIndirectSymbol) { |
| auto *SGV = dyn_cast<GlobalValue>(V); |
| if (!SGV) |
| return nullptr; |
| |
| // When linking a global from other modules than source & dest, skip |
| // materializing it because it would be mapped later when its containing |
| // module is linked. Linking it now would potentially pull in many types that |
| // may not be mapped properly. |
| if (SGV->getParent() != &DstM && SGV->getParent() != SrcM.get()) |
| return nullptr; |
| |
| Expected<Constant *> NewProto = linkGlobalValueProto(SGV, ForIndirectSymbol); |
| if (!NewProto) { |
| setError(NewProto.takeError()); |
| return nullptr; |
| } |
| if (!*NewProto) |
| return nullptr; |
| |
| GlobalValue *New = dyn_cast<GlobalValue>(*NewProto); |
| if (!New) |
| return *NewProto; |
| |
| // If we already created the body, just return. |
| if (auto *F = dyn_cast<Function>(New)) { |
| if (!F->isDeclaration()) |
| return New; |
| } else if (auto *V = dyn_cast<GlobalVariable>(New)) { |
| if (V->hasInitializer() || V->hasAppendingLinkage()) |
| return New; |
| } else if (auto *GA = dyn_cast<GlobalAlias>(New)) { |
| if (GA->getAliasee()) |
| return New; |
| } else if (auto *GI = dyn_cast<GlobalIFunc>(New)) { |
| if (GI->getResolver()) |
| return New; |
| } else { |
| llvm_unreachable("Invalid GlobalValue type"); |
| } |
| |
| // If the global is being linked for an indirect symbol, it may have already |
| // been scheduled to satisfy a regular symbol. Similarly, a global being linked |
| // for a regular symbol may have already been scheduled for an indirect |
| // symbol. Check for these cases by looking in the other value map and |
| // confirming the same value has been scheduled. If there is an entry in the |
| // ValueMap but the value is different, it means that the value already had a |
| // definition in the destination module (linkonce for instance), but we need a |
| // new definition for the indirect symbol ("New" will be different). |
| if ((ForIndirectSymbol && ValueMap.lookup(SGV) == New) || |
| (!ForIndirectSymbol && IndirectSymbolValueMap.lookup(SGV) == New)) |
| return New; |
| |
| if (ForIndirectSymbol || shouldLink(New, *SGV)) |
| setError(linkGlobalValueBody(*New, *SGV)); |
| |
| return New; |
| } |
| |
| /// Loop through the global variables in the src module and merge them into the |
| /// dest module. |
| GlobalVariable *IRLinker::copyGlobalVariableProto(const GlobalVariable *SGVar) { |
| // No linking to be performed or linking from the source: simply create an |
| // identical version of the symbol over in the dest module... the |
| // initializer will be filled in later by LinkGlobalInits. |
| GlobalVariable *NewDGV = |
| new GlobalVariable(DstM, TypeMap.get(SGVar->getValueType()), |
| SGVar->isConstant(), GlobalValue::ExternalLinkage, |
| /*init*/ nullptr, SGVar->getName(), |
| /*insertbefore*/ nullptr, SGVar->getThreadLocalMode(), |
| SGVar->getAddressSpace()); |
| NewDGV->setAlignment(MaybeAlign(SGVar->getAlignment())); |
| NewDGV->copyAttributesFrom(SGVar); |
| return NewDGV; |
| } |
| |
| AttributeList IRLinker::mapAttributeTypes(LLVMContext &C, AttributeList Attrs) { |
| for (unsigned i = 0; i < Attrs.getNumAttrSets(); ++i) { |
| for (int AttrIdx = Attribute::FirstTypeAttr; |
| AttrIdx <= Attribute::LastTypeAttr; AttrIdx++) { |
| Attribute::AttrKind TypedAttr = (Attribute::AttrKind)AttrIdx; |
| if (Attrs.hasAttributeAtIndex(i, TypedAttr)) { |
| if (Type *Ty = |
| Attrs.getAttributeAtIndex(i, TypedAttr).getValueAsType()) { |
| Attrs = Attrs.replaceAttributeTypeAtIndex(C, i, TypedAttr, |
| TypeMap.get(Ty)); |
| break; |
| } |
| } |
| } |
| } |
| return Attrs; |
| } |
| |
| /// Link the function in the source module into the destination module if |
| /// needed, setting up mapping information. |
| Function *IRLinker::copyFunctionProto(const Function *SF) { |
| // If there is no linkage to be performed or we are linking from the source, |
| // bring SF over. |
| auto *F = Function::Create(TypeMap.get(SF->getFunctionType()), |
| GlobalValue::ExternalLinkage, |
| SF->getAddressSpace(), SF->getName(), &DstM); |
| F->copyAttributesFrom(SF); |
| F->setAttributes(mapAttributeTypes(F->getContext(), F->getAttributes())); |
| return F; |
| } |
| |
| /// Set up prototypes for any indirect symbols that come over from the source |
| /// module. |
| GlobalValue *IRLinker::copyIndirectSymbolProto(const GlobalValue *SGV) { |
| // If there is no linkage to be performed or we're linking from the source, |
| // bring over SGA. |
| auto *Ty = TypeMap.get(SGV->getValueType()); |
| |
| if (auto *GA = dyn_cast<GlobalAlias>(SGV)) { |
| auto *DGA = GlobalAlias::create(Ty, SGV->getAddressSpace(), |
| GlobalValue::ExternalLinkage, |
| SGV->getName(), &DstM); |
| DGA->copyAttributesFrom(GA); |
| return DGA; |
| } |
| |
| if (auto *GI = dyn_cast<GlobalIFunc>(SGV)) { |
| auto *DGI = GlobalIFunc::create(Ty, SGV->getAddressSpace(), |
| GlobalValue::ExternalLinkage, |
| SGV->getName(), nullptr, &DstM); |
| DGI->copyAttributesFrom(GI); |
| return DGI; |
| } |
| |
| llvm_unreachable("Invalid source global value type"); |
| } |
| |
| GlobalValue *IRLinker::copyGlobalValueProto(const GlobalValue *SGV, |
| bool ForDefinition) { |
| GlobalValue *NewGV; |
| if (auto *SGVar = dyn_cast<GlobalVariable>(SGV)) { |
| NewGV = copyGlobalVariableProto(SGVar); |
| } else if (auto *SF = dyn_cast<Function>(SGV)) { |
| NewGV = copyFunctionProto(SF); |
| } else { |
| if (ForDefinition) |
| NewGV = copyIndirectSymbolProto(SGV); |
| else if (SGV->getValueType()->isFunctionTy()) |
| NewGV = |
| Function::Create(cast<FunctionType>(TypeMap.get(SGV->getValueType())), |
| GlobalValue::ExternalLinkage, SGV->getAddressSpace(), |
| SGV->getName(), &DstM); |
| else |
| NewGV = |
| new GlobalVariable(DstM, TypeMap.get(SGV->getValueType()), |
| /*isConstant*/ false, GlobalValue::ExternalLinkage, |
| /*init*/ nullptr, SGV->getName(), |
| /*insertbefore*/ nullptr, |
| SGV->getThreadLocalMode(), SGV->getAddressSpace()); |
| } |
| |
| if (ForDefinition) |
| NewGV->setLinkage(SGV->getLinkage()); |
| else if (SGV->hasExternalWeakLinkage()) |
| NewGV->setLinkage(GlobalValue::ExternalWeakLinkage); |
| |
| if (auto *NewGO = dyn_cast<GlobalObject>(NewGV)) { |
| // Metadata for global variables and function declarations is copied eagerly. |
| if (isa<GlobalVariable>(SGV) || SGV->isDeclaration()) |
| NewGO->copyMetadata(cast<GlobalObject>(SGV), 0); |
| } |
| |
| // Remove these copied constants in case this stays a declaration, since |
| // they point to the source module. If the def is linked the values will |
| // be mapped in during linkFunctionBody. |
| if (auto *NewF = dyn_cast<Function>(NewGV)) { |
| NewF->setPersonalityFn(nullptr); |
| NewF->setPrefixData(nullptr); |
| NewF->setPrologueData(nullptr); |
| } |
| |
| return NewGV; |
| } |
| |
| static StringRef getTypeNamePrefix(StringRef Name) { |
| size_t DotPos = Name.rfind('.'); |
| return (DotPos == 0 || DotPos == StringRef::npos || Name.back() == '.' || |
| !isdigit(static_cast<unsigned char>(Name[DotPos + 1]))) |
| ? Name |
| : Name.substr(0, DotPos); |
| } |
| |
| /// Loop over all of the linked values to compute type mappings. For example, |
| /// if we link "extern Foo *x" and "Foo *x = NULL", then we have two struct |
| /// types 'Foo' but one got renamed when the module was loaded into the same |
| /// LLVMContext. |
| void IRLinker::computeTypeMapping() { |
| for (GlobalValue &SGV : SrcM->globals()) { |
| GlobalValue *DGV = getLinkedToGlobal(&SGV); |
| if (!DGV) |
| continue; |
| |
| if (!DGV->hasAppendingLinkage() || !SGV.hasAppendingLinkage()) { |
| TypeMap.addTypeMapping(DGV->getType(), SGV.getType()); |
| continue; |
| } |
| |
| // Unify the element type of appending arrays. |
| ArrayType *DAT = cast<ArrayType>(DGV->getValueType()); |
| ArrayType *SAT = cast<ArrayType>(SGV.getValueType()); |
| TypeMap.addTypeMapping(DAT->getElementType(), SAT->getElementType()); |
| } |
| |
| for (GlobalValue &SGV : *SrcM) |
| if (GlobalValue *DGV = getLinkedToGlobal(&SGV)) { |
| if (DGV->getType() == SGV.getType()) { |
| // If the types of DGV and SGV are the same, it means that DGV is from |
| // the source module and got added to DstM from a shared metadata. We |
| // shouldn't map this type to itself in case the type's components get |
| // remapped to a new type from DstM (for instance, during the loop over |
| // SrcM->getIdentifiedStructTypes() below). |
| continue; |
| } |
| |
| TypeMap.addTypeMapping(DGV->getType(), SGV.getType()); |
| } |
| |
| for (GlobalValue &SGV : SrcM->aliases()) |
| if (GlobalValue *DGV = getLinkedToGlobal(&SGV)) |
| TypeMap.addTypeMapping(DGV->getType(), SGV.getType()); |
| |
| // Incorporate types by name, scanning all the types in the source module. |
| // At this point, the destination module may have a type "%foo = { i32 }" for |
| // example. When the source module got loaded into the same LLVMContext, if |
| // it had the same type, it would have been renamed to "%foo.42 = { i32 }". |
| std::vector<StructType *> Types = SrcM->getIdentifiedStructTypes(); |
| for (StructType *ST : Types) { |
| if (!ST->hasName()) |
| continue; |
| |
| if (TypeMap.DstStructTypesSet.hasType(ST)) { |
| // This is actually a type from the destination module. |
| // getIdentifiedStructTypes() can have found it by walking debug info |
| // metadata nodes, some of which get linked by name when ODR Type Uniquing |
| // is enabled on the Context, from the source to the destination module. |
| continue; |
| } |
| |
| auto STTypePrefix = getTypeNamePrefix(ST->getName()); |
| if (STTypePrefix.size() == ST->getName().size()) |
| continue; |
| |
| // Check to see if the destination module has a struct with the prefix name. |
| StructType *DST = StructType::getTypeByName(ST->getContext(), STTypePrefix); |
| if (!DST) |
| continue; |
| |
| // Don't use it if this actually came from the source module. They're in |
| // the same LLVMContext after all. Also don't use it unless the type is |
| // actually used in the destination module. This can happen in situations |
| // like this: |
| // |
| // Module A Module B |
| // -------- -------- |
| // %Z = type { %A } %B = type { %C.1 } |
| // %A = type { %B.1, [7 x i8] } %C.1 = type { i8* } |
| // %B.1 = type { %C } %A.2 = type { %B.3, [5 x i8] } |
| // %C = type { i8* } %B.3 = type { %C.1 } |
| // |
| // When we link Module B with Module A, the '%B' in Module B is |
| // used. However, that would then use '%C.1'. But when we process '%C.1', |
| // we prefer to take the '%C' version. So we are then left with both |
| // '%C.1' and '%C' being used for the same types. This leads to some |
| // variables using one type and some using the other. |
| if (TypeMap.DstStructTypesSet.hasType(DST)) |
| TypeMap.addTypeMapping(DST, ST); |
| } |
| |
| // Now that we have discovered all of the type equivalences, get a body for |
| // any 'opaque' types in the dest module that are now resolved. |
| TypeMap.linkDefinedTypeBodies(); |
| } |
| |
| static void getArrayElements(const Constant *C, |
| SmallVectorImpl<Constant *> &Dest) { |
| unsigned NumElements = cast<ArrayType>(C->getType())->getNumElements(); |
| |
| for (unsigned i = 0; i != NumElements; ++i) |
| Dest.push_back(C->getAggregateElement(i)); |
| } |
| |
| /// If there were any appending global variables, link them together now. |
| Expected<Constant *> |
| IRLinker::linkAppendingVarProto(GlobalVariable *DstGV, |
| const GlobalVariable *SrcGV) { |
| // Check that both variables have compatible properties. |
| if (DstGV && !DstGV->isDeclaration() && !SrcGV->isDeclaration()) { |
| if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage()) |
| return stringErr( |
| "Linking globals named '" + SrcGV->getName() + |
| "': can only link appending global with another appending " |
| "global!"); |
| |
| if (DstGV->isConstant() != SrcGV->isConstant()) |
| return stringErr("Appending variables linked with different const'ness!"); |
| |
| if (DstGV->getAlignment() != SrcGV->getAlignment()) |
| return stringErr( |
| "Appending variables with different alignment need to be linked!"); |
| |
| if (DstGV->getVisibility() != SrcGV->getVisibility()) |
| return stringErr( |
| "Appending variables with different visibility need to be linked!"); |
| |
| if (DstGV->hasGlobalUnnamedAddr() != SrcGV->hasGlobalUnnamedAddr()) |
| return stringErr( |
| "Appending variables with different unnamed_addr need to be linked!"); |
| |
| if (DstGV->getSection() != SrcGV->getSection()) |
| return stringErr( |
| "Appending variables with different section name need to be linked!"); |
| } |
| |
| // Do not need to do anything if source is a declaration. |
| if (SrcGV->isDeclaration()) |
| return DstGV; |
| |
| Type *EltTy = cast<ArrayType>(TypeMap.get(SrcGV->getValueType())) |
| ->getElementType(); |
| |
| // FIXME: This upgrade is done during linking to support the C API. Once the |
| // old form is deprecated, we should move this upgrade to |
| // llvm::UpgradeGlobalVariable() and simplify the logic here and in |
| // Mapper::mapAppendingVariable() in ValueMapper.cpp. |
| StringRef Name = SrcGV->getName(); |
| bool IsNewStructor = false; |
| bool IsOldStructor = false; |
| if (Name == "llvm.global_ctors" || Name == "llvm.global_dtors") { |
| if (cast<StructType>(EltTy)->getNumElements() == 3) |
| IsNewStructor = true; |
| else |
| IsOldStructor = true; |
| } |
| |
| PointerType *VoidPtrTy = Type::getInt8Ty(SrcGV->getContext())->getPointerTo(); |
| if (IsOldStructor) { |
| auto &ST = *cast<StructType>(EltTy); |
| Type *Tys[3] = {ST.getElementType(0), ST.getElementType(1), VoidPtrTy}; |
| EltTy = StructType::get(SrcGV->getContext(), Tys, false); |
| } |
| |
| uint64_t DstNumElements = 0; |
| if (DstGV && !DstGV->isDeclaration()) { |
| ArrayType *DstTy = cast<ArrayType>(DstGV->getValueType()); |
| DstNumElements = DstTy->getNumElements(); |
| |
| // Check to see that they two arrays agree on type. |
| if (EltTy != DstTy->getElementType()) |
| return stringErr("Appending variables with different element types!"); |
| } |
| |
| SmallVector<Constant *, 16> SrcElements; |
| getArrayElements(SrcGV->getInitializer(), SrcElements); |
| |
| if (IsNewStructor) { |
| erase_if(SrcElements, [this](Constant *E) { |
| auto *Key = |
| dyn_cast<GlobalValue>(E->getAggregateElement(2)->stripPointerCasts()); |
| if (!Key) |
| return false; |
| GlobalValue *DGV = getLinkedToGlobal(Key); |
| return !shouldLink(DGV, *Key); |
| }); |
| } |
| uint64_t NewSize = DstNumElements + SrcElements.size(); |
| ArrayType *NewType = ArrayType::get(EltTy, NewSize); |
| |
| // Create the new global variable. |
| GlobalVariable *NG = new GlobalVariable( |
| DstM, NewType, SrcGV->isConstant(), SrcGV->getLinkage(), |
| /*init*/ nullptr, /*name*/ "", DstGV, SrcGV->getThreadLocalMode(), |
| SrcGV->getAddressSpace()); |
| |
| NG->copyAttributesFrom(SrcGV); |
| forceRenaming(NG, SrcGV->getName()); |
| |
| Constant *Ret = ConstantExpr::getBitCast(NG, TypeMap.get(SrcGV->getType())); |
| |
| Mapper.scheduleMapAppendingVariable( |
| *NG, |
| (DstGV && !DstGV->isDeclaration()) ? DstGV->getInitializer() : nullptr, |
| IsOldStructor, SrcElements); |
| |
| // Replace any uses of the two global variables with uses of the new |
| // global. |
| if (DstGV) { |
| RAUWWorklist.push_back( |
| std::make_pair(DstGV, ConstantExpr::getBitCast(NG, DstGV->getType()))); |
| } |
| |
| return Ret; |
| } |
| |
| bool IRLinker::shouldLink(GlobalValue *DGV, GlobalValue &SGV) { |
| if (ValuesToLink.count(&SGV) || SGV.hasLocalLinkage()) |
| return true; |
| |
| if (DGV && !DGV->isDeclarationForLinker()) |
| return false; |
| |
| if (SGV.isDeclaration() || DoneLinkingBodies) |
| return false; |
| |
| // Callback to the client to give a chance to lazily add the Global to the |
| // list of value to link. |
| bool LazilyAdded = false; |
| AddLazyFor(SGV, [this, &LazilyAdded](GlobalValue &GV) { |
| maybeAdd(&GV); |
| LazilyAdded = true; |
| }); |
| return LazilyAdded; |
| } |
| |
| Expected<Constant *> IRLinker::linkGlobalValueProto(GlobalValue *SGV, |
| bool ForIndirectSymbol) { |
| GlobalValue *DGV = getLinkedToGlobal(SGV); |
| |
| bool ShouldLink = shouldLink(DGV, *SGV); |
| |
| // just missing from map |
| if (ShouldLink) { |
| auto I = ValueMap.find(SGV); |
| if (I != ValueMap.end()) |
| return cast<Constant>(I->second); |
| |
| I = IndirectSymbolValueMap.find(SGV); |
| if (I != IndirectSymbolValueMap.end()) |
| return cast<Constant>(I->second); |
| } |
| |
| if (!ShouldLink && ForIndirectSymbol) |
| DGV = nullptr; |
| |
| // Handle the ultra special appending linkage case first. |
| if (SGV->hasAppendingLinkage() || (DGV && DGV->hasAppendingLinkage())) |
| return linkAppendingVarProto(cast_or_null<GlobalVariable>(DGV), |
| cast<GlobalVariable>(SGV)); |
| |
| bool NeedsRenaming = false; |
| GlobalValue *NewGV; |
| if (DGV && !ShouldLink) { |
| NewGV = DGV; |
| } else { |
| // If we are done linking global value bodies (i.e. we are performing |
| // metadata linking), don't link in the global value due to this |
| // reference, simply map it to null. |
| if (DoneLinkingBodies) |
| return nullptr; |
| |
| NewGV = copyGlobalValueProto(SGV, ShouldLink || ForIndirectSymbol); |
| if (ShouldLink || !ForIndirectSymbol) |
| NeedsRenaming = true; |
| } |
| |
| // Overloaded intrinsics have overloaded types names as part of their |
| // names. If we renamed overloaded types we should rename the intrinsic |
| // as well. |
| if (Function *F = dyn_cast<Function>(NewGV)) |
| if (auto Remangled = Intrinsic::remangleIntrinsicFunction(F)) { |
| NewGV->eraseFromParent(); |
| NewGV = Remangled.getValue(); |
| NeedsRenaming = false; |
| } |
| |
| if (NeedsRenaming) |
| forceRenaming(NewGV, SGV->getName()); |
| |
| if (ShouldLink || ForIndirectSymbol) { |
| if (const Comdat *SC = SGV->getComdat()) { |
| if (auto *GO = dyn_cast<GlobalObject>(NewGV)) { |
| Comdat *DC = DstM.getOrInsertComdat(SC->getName()); |
| DC->setSelectionKind(SC->getSelectionKind()); |
| GO->setComdat(DC); |
| } |
| } |
| } |
| |
| if (!ShouldLink && ForIndirectSymbol) |
| NewGV->setLinkage(GlobalValue::InternalLinkage); |
| |
| Constant *C = NewGV; |
| // Only create a bitcast if necessary. In particular, with |
| // DebugTypeODRUniquing we may reach metadata in the destination module |
| // containing a GV from the source module, in which case SGV will be |
| // the same as DGV and NewGV, and TypeMap.get() will assert since it |
| // assumes it is being invoked on a type in the source module. |
| if (DGV && NewGV != SGV) { |
| C = ConstantExpr::getPointerBitCastOrAddrSpaceCast( |
| NewGV, TypeMap.get(SGV->getType())); |
| } |
| |
| if (DGV && NewGV != DGV) { |
| // Schedule "replace all uses with" to happen after materializing is |
| // done. It is not safe to do it now, since ValueMapper may be holding |
| // pointers to constants that will get deleted if RAUW runs. |
| RAUWWorklist.push_back(std::make_pair( |
| DGV, |
| ConstantExpr::getPointerBitCastOrAddrSpaceCast(NewGV, DGV->getType()))); |
| } |
| |
| return C; |
| } |
| |
| /// Update the initializers in the Dest module now that all globals that may be |
| /// referenced are in Dest. |
| void IRLinker::linkGlobalVariable(GlobalVariable &Dst, GlobalVariable &Src) { |
| // Figure out what the initializer looks like in the dest module. |
| Mapper.scheduleMapGlobalInitializer(Dst, *Src.getInitializer()); |
| } |
| |
| /// Copy the source function over into the dest function and fix up references |
| /// to values. At this point we know that Dest is an external function, and |
| /// that Src is not. |
| Error IRLinker::linkFunctionBody(Function &Dst, Function &Src) { |
| assert(Dst.isDeclaration() && !Src.isDeclaration()); |
| |
| // Materialize if needed. |
| if (Error Err = Src.materialize()) |
| return Err; |
| |
| // Link in the operands without remapping. |
| if (Src.hasPrefixData()) |
| Dst.setPrefixData(Src.getPrefixData()); |
| if (Src.hasPrologueData()) |
| Dst.setPrologueData(Src.getPrologueData()); |
| if (Src.hasPersonalityFn()) |
| Dst.setPersonalityFn(Src.getPersonalityFn()); |
| |
| // Copy over the metadata attachments without remapping. |
| Dst.copyMetadata(&Src, 0); |
| |
| // Steal arguments and splice the body of Src into Dst. |
| Dst.stealArgumentListFrom(Src); |
| Dst.getBasicBlockList().splice(Dst.end(), Src.getBasicBlockList()); |
| |
| // Everything has been moved over. Remap it. |
| Mapper.scheduleRemapFunction(Dst); |
| return Error::success(); |
| } |
| |
| void IRLinker::linkAliasAliasee(GlobalAlias &Dst, GlobalAlias &Src) { |
| Mapper.scheduleMapGlobalAlias(Dst, *Src.getAliasee(), IndirectSymbolMCID); |
| } |
| |
| void IRLinker::linkIFuncResolver(GlobalIFunc &Dst, GlobalIFunc &Src) { |
| Mapper.scheduleMapGlobalIFunc(Dst, *Src.getResolver(), IndirectSymbolMCID); |
| } |
| |
| Error IRLinker::linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src) { |
| if (auto *F = dyn_cast<Function>(&Src)) |
| return linkFunctionBody(cast<Function>(Dst), *F); |
| if (auto *GVar = dyn_cast<GlobalVariable>(&Src)) { |
| linkGlobalVariable(cast<GlobalVariable>(Dst), *GVar); |
| return Error::success(); |
| } |
| if (auto *GA = dyn_cast<GlobalAlias>(&Src)) { |
| linkAliasAliasee(cast<GlobalAlias>(Dst), *GA); |
| return Error::success(); |
| } |
| linkIFuncResolver(cast<GlobalIFunc>(Dst), cast<GlobalIFunc>(Src)); |
| return Error::success(); |
| } |
| |
| void IRLinker::flushRAUWWorklist() { |
| for (const auto &Elem : RAUWWorklist) { |
| GlobalValue *Old; |
| Value *New; |
| std::tie(Old, New) = Elem; |
| |
| Old->replaceAllUsesWith(New); |
| Old->eraseFromParent(); |
| } |
| RAUWWorklist.clear(); |
| } |
| |
| void IRLinker::prepareCompileUnitsForImport() { |
| NamedMDNode *SrcCompileUnits = SrcM->getNamedMetadata("llvm.dbg.cu"); |
| if (!SrcCompileUnits) |
| return; |
| // When importing for ThinLTO, prevent importing of types listed on |
| // the DICompileUnit that we don't need a copy of in the importing |
| // module. They will be emitted by the originating module. |
| for (unsigned I = 0, E = SrcCompileUnits->getNumOperands(); I != E; ++I) { |
| auto *CU = cast<DICompileUnit>(SrcCompileUnits->getOperand(I)); |
| assert(CU && "Expected valid compile unit"); |
| // Enums, macros, and retained types don't need to be listed on the |
| // imported DICompileUnit. This means they will only be imported |
| // if reached from the mapped IR. |
| CU->replaceEnumTypes(nullptr); |
| CU->replaceMacros(nullptr); |
| CU->replaceRetainedTypes(nullptr); |
| |
| // The original definition (or at least its debug info - if the variable is |
| // internalized and optimized away) will remain in the source module, so |
| // there's no need to import them. |
| // If LLVM ever does more advanced optimizations on global variables |
| // (removing/localizing write operations, for instance) that can track |
| // through debug info, this decision may need to be revisited - but do so |
| // with care when it comes to debug info size. Emitting small CUs containing |
| // only a few imported entities into every destination module may be very |
| // size inefficient. |
| CU->replaceGlobalVariables(nullptr); |
| |
| // Imported entities only need to be mapped in if they have local |
| // scope, as those might correspond to an imported entity inside a |
| // function being imported (any locally scoped imported entities that |
| // don't end up referenced by an imported function will not be emitted |
| // into the object). Imported entities not in a local scope |
| // (e.g. on the namespace) only need to be emitted by the originating |
| // module. Create a list of the locally scoped imported entities, and |
| // replace the source CUs imported entity list with the new list, so |
| // only those are mapped in. |
| // FIXME: Locally-scoped imported entities could be moved to the |
| // functions they are local to instead of listing them on the CU, and |
| // we would naturally only link in those needed by function importing. |
| SmallVector<TrackingMDNodeRef, 4> AllImportedModules; |
| bool ReplaceImportedEntities = false; |
| for (auto *IE : CU->getImportedEntities()) { |
| DIScope *Scope = IE->getScope(); |
| assert(Scope && "Invalid Scope encoding!"); |
| if (isa<DILocalScope>(Scope)) |
| AllImportedModules.emplace_back(IE); |
| else |
| ReplaceImportedEntities = true; |
| } |
| if (ReplaceImportedEntities) { |
| if (!AllImportedModules.empty()) |
| CU->replaceImportedEntities(MDTuple::get( |
| CU->getContext(), |
| SmallVector<Metadata *, 16>(AllImportedModules.begin(), |
| AllImportedModules.end()))); |
| else |
| // If there were no local scope imported entities, we can map |
| // the whole list to nullptr. |
| CU->replaceImportedEntities(nullptr); |
| } |
| } |
| } |
| |
| /// Insert all of the named MDNodes in Src into the Dest module. |
| void IRLinker::linkNamedMDNodes() { |
| const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata(); |
| for (const NamedMDNode &NMD : SrcM->named_metadata()) { |
| // Don't link module flags here. Do them separately. |
| if (&NMD == SrcModFlags) |
| continue; |
| // Don't import pseudo probe descriptors here for thinLTO. They will be |
| // emitted by the originating module. |
| if (IsPerformingImport && NMD.getName() == PseudoProbeDescMetadataName) |
| continue; |
| NamedMDNode *DestNMD = DstM.getOrInsertNamedMetadata(NMD.getName()); |
| // Add Src elements into Dest node. |
| for (const MDNode *Op : NMD.operands()) |
| DestNMD->addOperand(Mapper.mapMDNode(*Op)); |
| } |
| } |
| |
| /// Merge the linker flags in Src into the Dest module. |
| Error IRLinker::linkModuleFlagsMetadata() { |
| // If the source module has no module flags, we are done. |
| const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata(); |
| if (!SrcModFlags) |
| return Error::success(); |
| |
| // If the destination module doesn't have module flags yet, then just copy |
| // over the source module's flags. |
| NamedMDNode *DstModFlags = DstM.getOrInsertModuleFlagsMetadata(); |
| if (DstModFlags->getNumOperands() == 0) { |
| for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I) |
| DstModFlags->addOperand(SrcModFlags->getOperand(I)); |
| |
| return Error::success(); |
| } |
| |
| // First build a map of the existing module flags and requirements. |
| DenseMap<MDString *, std::pair<MDNode *, unsigned>> Flags; |
| SmallSetVector<MDNode *, 16> Requirements; |
| for (unsigned I = 0, E = DstModFlags->getNumOperands(); I != E; ++I) { |
| MDNode *Op = DstModFlags->getOperand(I); |
| ConstantInt *Behavior = mdconst::extract<ConstantInt>(Op->getOperand(0)); |
| MDString *ID = cast<MDString>(Op->getOperand(1)); |
| |
| if (Behavior->getZExtValue() == Module::Require) { |
| Requirements.insert(cast<MDNode>(Op->getOperand(2))); |
| } else { |
| Flags[ID] = std::make_pair(Op, I); |
| } |
| } |
| |
| // Merge in the flags from the source module, and also collect its set of |
| // requirements. |
| for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I) { |
| MDNode *SrcOp = SrcModFlags->getOperand(I); |
| ConstantInt *SrcBehavior = |
| mdconst::extract<ConstantInt>(SrcOp->getOperand(0)); |
| MDString *ID = cast<MDString>(SrcOp->getOperand(1)); |
| MDNode *DstOp; |
| unsigned DstIndex; |
| std::tie(DstOp, DstIndex) = Flags.lookup(ID); |
| unsigned SrcBehaviorValue = SrcBehavior->getZExtValue(); |
| |
| // If this is a requirement, add it and continue. |
| if (SrcBehaviorValue == Module::Require) { |
| // If the destination module does not already have this requirement, add |
| // it. |
| if (Requirements.insert(cast<MDNode>(SrcOp->getOperand(2)))) { |
| DstModFlags->addOperand(SrcOp); |
| } |
| continue; |
| } |
| |
| // If there is no existing flag with this ID, just add it. |
| if (!DstOp) { |
| Flags[ID] = std::make_pair(SrcOp, DstModFlags->getNumOperands()); |
| DstModFlags->addOperand(SrcOp); |
| continue; |
| } |
| |
| // Otherwise, perform a merge. |
| ConstantInt *DstBehavior = |
| mdconst::extract<ConstantInt>(DstOp->getOperand(0)); |
| unsigned DstBehaviorValue = DstBehavior->getZExtValue(); |
| |
| auto overrideDstValue = [&]() { |
| DstModFlags->setOperand(DstIndex, SrcOp); |
| Flags[ID].first = SrcOp; |
| }; |
| |
| // If either flag has override behavior, handle it first. |
| if (DstBehaviorValue == Module::Override) { |
| // Diagnose inconsistent flags which both have override behavior. |
| if (SrcBehaviorValue == Module::Override && |
| SrcOp->getOperand(2) != DstOp->getOperand(2)) |
| return stringErr("linking module flags '" + ID->getString() + |
| "': IDs have conflicting override values in '" + |
| SrcM->getModuleIdentifier() + "' and '" + |
| DstM.getModuleIdentifier() + "'"); |
| continue; |
| } else if (SrcBehaviorValue == Module::Override) { |
| // Update the destination flag to that of the source. |
| overrideDstValue(); |
| continue; |
| } |
| |
| // Diagnose inconsistent merge behavior types. |
| if (SrcBehaviorValue != DstBehaviorValue) { |
| bool MaxAndWarn = (SrcBehaviorValue == Module::Max && |
| DstBehaviorValue == Module::Warning) || |
| (DstBehaviorValue == Module::Max && |
| SrcBehaviorValue == Module::Warning); |
| if (!MaxAndWarn) |
| return stringErr("linking module flags '" + ID->getString() + |
| "': IDs have conflicting behaviors in '" + |
| SrcM->getModuleIdentifier() + "' and '" + |
| DstM.getModuleIdentifier() + "'"); |
| } |
| |
| auto replaceDstValue = [&](MDNode *New) { |
| Metadata *FlagOps[] = {DstOp->getOperand(0), ID, New}; |
| MDNode *Flag = MDNode::get(DstM.getContext(), FlagOps); |
| DstModFlags->setOperand(DstIndex, Flag); |
| Flags[ID].first = Flag; |
| }; |
| |
| // Emit a warning if the values differ and either source or destination |
| // request Warning behavior. |
| if ((DstBehaviorValue == Module::Warning || |
| SrcBehaviorValue == Module::Warning) && |
| SrcOp->getOperand(2) != DstOp->getOperand(2)) { |
| std::string Str; |
| raw_string_ostream(Str) |
| << "linking module flags '" << ID->getString() |
| << "': IDs have conflicting values ('" << *SrcOp->getOperand(2) |
| << "' from " << SrcM->getModuleIdentifier() << " with '" |
| << *DstOp->getOperand(2) << "' from " << DstM.getModuleIdentifier() |
| << ')'; |
| emitWarning(Str); |
| } |
| |
| // Choose the maximum if either source or destination request Max behavior. |
| if (DstBehaviorValue == Module::Max || SrcBehaviorValue == Module::Max) { |
| ConstantInt *DstValue = |
| mdconst::extract<ConstantInt>(DstOp->getOperand(2)); |
| ConstantInt *SrcValue = |
| mdconst::extract<ConstantInt>(SrcOp->getOperand(2)); |
| |
| // The resulting flag should have a Max behavior, and contain the maximum |
| // value from between the source and destination values. |
| Metadata *FlagOps[] = { |
| (DstBehaviorValue != Module::Max ? SrcOp : DstOp)->getOperand(0), ID, |
| (SrcValue->getZExtValue() > DstValue->getZExtValue() ? SrcOp : DstOp) |
| ->getOperand(2)}; |
| MDNode *Flag = MDNode::get(DstM.getContext(), FlagOps); |
| DstModFlags->setOperand(DstIndex, Flag); |
| Flags[ID].first = Flag; |
| continue; |
| } |
| |
| // Perform the merge for standard behavior types. |
| switch (SrcBehaviorValue) { |
| case Module::Require: |
| case Module::Override: |
| llvm_unreachable("not possible"); |
| case Module::Error: { |
| // Emit an error if the values differ. |
| if (SrcOp->getOperand(2) != DstOp->getOperand(2)) |
| return stringErr("linking module flags '" + ID->getString() + |
| "': IDs have conflicting values in '" + |
| SrcM->getModuleIdentifier() + "' and '" + |
| DstM.getModuleIdentifier() + "'"); |
| continue; |
| } |
| case Module::Warning: { |
| break; |
| } |
| case Module::Max: { |
| break; |
| } |
| case Module::Append: { |
| MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2)); |
| MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2)); |
| SmallVector<Metadata *, 8> MDs; |
| MDs.reserve(DstValue->getNumOperands() + SrcValue->getNumOperands()); |
| MDs.append(DstValue->op_begin(), DstValue->op_end()); |
| MDs.append(SrcValue->op_begin(), SrcValue->op_end()); |
| |
| replaceDstValue(MDNode::get(DstM.getContext(), MDs)); |
| break; |
| } |
| case Module::AppendUnique: { |
| SmallSetVector<Metadata *, 16> Elts; |
| MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2)); |
| MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2)); |
| Elts.insert(DstValue->op_begin(), DstValue->op_end()); |
| Elts.insert(SrcValue->op_begin(), SrcValue->op_end()); |
| |
| replaceDstValue(MDNode::get(DstM.getContext(), |
| makeArrayRef(Elts.begin(), Elts.end()))); |
| break; |
| } |
| } |
| |
| } |
| |
| // Check all of the requirements. |
| for (unsigned I = 0, E = Requirements.size(); I != E; ++I) { |
| MDNode *Requirement = Requirements[I]; |
| MDString *Flag = cast<MDString>(Requirement->getOperand(0)); |
| Metadata *ReqValue = Requirement->getOperand(1); |
| |
| MDNode *Op = Flags[Flag].first; |
| if (!Op || Op->getOperand(2) != ReqValue) |
| return stringErr("linking module flags '" + Flag->getString() + |
| "': does not have the required value"); |
| } |
| return Error::success(); |
| } |
| |
| /// Return InlineAsm adjusted with target-specific directives if required. |
| /// For ARM and Thumb, we have to add directives to select the appropriate ISA |
| /// to support mixing module-level inline assembly from ARM and Thumb modules. |
| static std::string adjustInlineAsm(const std::string &InlineAsm, |
| const Triple &Triple) { |
| if (Triple.getArch() == Triple::thumb || Triple.getArch() == Triple::thumbeb) |
| return ".text\n.balign 2\n.thumb\n" + InlineAsm; |
| if (Triple.getArch() == Triple::arm || Triple.getArch() == Triple::armeb) |
| return ".text\n.balign 4\n.arm\n" + InlineAsm; |
| return InlineAsm; |
| } |
| |
| Error IRLinker::run() { |
| // Ensure metadata materialized before value mapping. |
| if (SrcM->getMaterializer()) |
| if (Error Err = SrcM->getMaterializer()->materializeMetadata()) |
| return Err; |
| |
| // Inherit the target data from the source module if the destination module |
| // doesn't have one already. |
| if (DstM.getDataLayout().isDefault()) |
| DstM.setDataLayout(SrcM->getDataLayout()); |
| |
| // Copy the target triple from the source to dest if the dest's is empty. |
| if (DstM.getTargetTriple().empty() && !SrcM->getTargetTriple().empty()) |
| DstM.setTargetTriple(SrcM->getTargetTriple()); |
| |
| Triple SrcTriple(SrcM->getTargetTriple()), DstTriple(DstM.getTargetTriple()); |
| |
| // During CUDA compilation we have to link with the bitcode supplied with |
| // CUDA. libdevice bitcode either has no data layout set (pre-CUDA-11), or has |
| // the layout that is different from the one used by LLVM/clang (it does not |
| // include i128). Issuing a warning is not very helpful as there's not much |
| // the user can do about it. |
| bool EnableDLWarning = true; |
| bool EnableTripleWarning = true; |
| if (SrcTriple.isNVPTX() && DstTriple.isNVPTX()) { |
| std::string ModuleId = SrcM->getModuleIdentifier(); |
| StringRef FileName = llvm::sys::path::filename(ModuleId); |
| bool SrcIsLibDevice = |
| FileName.startswith("libdevice") && FileName.endswith(".10.bc"); |
| bool SrcHasLibDeviceDL = |
| (SrcM->getDataLayoutStr().empty() || |
| SrcM->getDataLayoutStr() == "e-i64:64-v16:16-v32:32-n16:32:64"); |
| // libdevice bitcode uses nvptx64-nvidia-gpulibs or just |
| // 'nvptx-unknown-unknown' triple (before CUDA-10.x) and is compatible with |
| // all NVPTX variants. |
| bool SrcHasLibDeviceTriple = (SrcTriple.getVendor() == Triple::NVIDIA && |
| SrcTriple.getOSName() == "gpulibs") || |
| (SrcTriple.getVendorName() == "unknown" && |
| SrcTriple.getOSName() == "unknown"); |
| EnableTripleWarning = !(SrcIsLibDevice && SrcHasLibDeviceTriple); |
| EnableDLWarning = !(SrcIsLibDevice && SrcHasLibDeviceDL); |
| } |
| |
| if (EnableDLWarning && (SrcM->getDataLayout() != DstM.getDataLayout())) { |
| emitWarning("Linking two modules of different data layouts: '" + |
| SrcM->getModuleIdentifier() + "' is '" + |
| SrcM->getDataLayoutStr() + "' whereas '" + |
| DstM.getModuleIdentifier() + "' is '" + |
| DstM.getDataLayoutStr() + "'\n"); |
| } |
| |
| if (EnableTripleWarning && !SrcM->getTargetTriple().empty() && |
| !SrcTriple.isCompatibleWith(DstTriple)) |
| emitWarning("Linking two modules of different target triples: '" + |
| SrcM->getModuleIdentifier() + "' is '" + |
| SrcM->getTargetTriple() + "' whereas '" + |
| DstM.getModuleIdentifier() + "' is '" + DstM.getTargetTriple() + |
| "'\n"); |
| |
| DstM.setTargetTriple(SrcTriple.merge(DstTriple)); |
| |
| // Loop over all of the linked values to compute type mappings. |
| computeTypeMapping(); |
| |
| std::reverse(Worklist.begin(), Worklist.end()); |
| while (!Worklist.empty()) { |
| GlobalValue *GV = Worklist.back(); |
| Worklist.pop_back(); |
| |
| // Already mapped. |
| if (ValueMap.find(GV) != ValueMap.end() || |
| IndirectSymbolValueMap.find(GV) != IndirectSymbolValueMap.end()) |
| continue; |
| |
| assert(!GV->isDeclaration()); |
| Mapper.mapValue(*GV); |
| if (FoundError) |
| return std::move(*FoundError); |
| flushRAUWWorklist(); |
| } |
| |
| // Note that we are done linking global value bodies. This prevents |
| // metadata linking from creating new references. |
| DoneLinkingBodies = true; |
| Mapper.addFlags(RF_NullMapMissingGlobalValues); |
| |
| // Remap all of the named MDNodes in Src into the DstM module. We do this |
| // after linking GlobalValues so that MDNodes that reference GlobalValues |
| // are properly remapped. |
| linkNamedMDNodes(); |
| |
| if (!IsPerformingImport && !SrcM->getModuleInlineAsm().empty()) { |
| // Append the module inline asm string. |
| DstM.appendModuleInlineAsm(adjustInlineAsm(SrcM->getModuleInlineAsm(), |
| SrcTriple)); |
| } else if (IsPerformingImport) { |
| // Import any symver directives for symbols in DstM. |
| ModuleSymbolTable::CollectAsmSymvers(*SrcM, |
| [&](StringRef Name, StringRef Alias) { |
| if (DstM.getNamedValue(Name)) { |
| SmallString<256> S(".symver "); |
| S += Name; |
| S += ", "; |
| S += Alias; |
| DstM.appendModuleInlineAsm(S); |
| } |
| }); |
| } |
| |
| // Reorder the globals just added to the destination module to match their |
| // original order in the source module. |
| Module::GlobalListType &Globals = DstM.getGlobalList(); |
| for (GlobalVariable &GV : SrcM->globals()) { |
| if (GV.hasAppendingLinkage()) |
| continue; |
| Value *NewValue = Mapper.mapValue(GV); |
| if (NewValue) { |
| auto *NewGV = dyn_cast<GlobalVariable>(NewValue->stripPointerCasts()); |
| if (NewGV) |
| Globals.splice(Globals.end(), Globals, NewGV->getIterator()); |
| } |
| } |
| |
| // Merge the module flags into the DstM module. |
| return linkModuleFlagsMetadata(); |
| } |
| |
| IRMover::StructTypeKeyInfo::KeyTy::KeyTy(ArrayRef<Type *> E, bool P) |
| : ETypes(E), IsPacked(P) {} |
| |
| IRMover::StructTypeKeyInfo::KeyTy::KeyTy(const StructType *ST) |
| : ETypes(ST->elements()), IsPacked(ST->isPacked()) {} |
| |
| bool IRMover::StructTypeKeyInfo::KeyTy::operator==(const KeyTy &That) const { |
| return IsPacked == That.IsPacked && ETypes == That.ETypes; |
| } |
| |
| bool IRMover::StructTypeKeyInfo::KeyTy::operator!=(const KeyTy &That) const { |
| return !this->operator==(That); |
| } |
| |
| StructType *IRMover::StructTypeKeyInfo::getEmptyKey() { |
| return DenseMapInfo<StructType *>::getEmptyKey(); |
| } |
| |
| StructType *IRMover::StructTypeKeyInfo::getTombstoneKey() { |
| return DenseMapInfo<StructType *>::getTombstoneKey(); |
| } |
| |
| unsigned IRMover::StructTypeKeyInfo::getHashValue(const KeyTy &Key) { |
| return hash_combine(hash_combine_range(Key.ETypes.begin(), Key.ETypes.end()), |
| Key.IsPacked); |
| } |
| |
| unsigned IRMover::StructTypeKeyInfo::getHashValue(const StructType *ST) { |
| return getHashValue(KeyTy(ST)); |
| } |
| |
| bool IRMover::StructTypeKeyInfo::isEqual(const KeyTy &LHS, |
| const StructType *RHS) { |
| if (RHS == getEmptyKey() || RHS == getTombstoneKey()) |
| return false; |
| return LHS == KeyTy(RHS); |
| } |
| |
| bool IRMover::StructTypeKeyInfo::isEqual(const StructType *LHS, |
| const StructType *RHS) { |
| if (RHS == getEmptyKey() || RHS == getTombstoneKey()) |
| return LHS == RHS; |
| return KeyTy(LHS) == KeyTy(RHS); |
| } |
| |
| void IRMover::IdentifiedStructTypeSet::addNonOpaque(StructType *Ty) { |
| assert(!Ty->isOpaque()); |
| NonOpaqueStructTypes.insert(Ty); |
| } |
| |
| void IRMover::IdentifiedStructTypeSet::switchToNonOpaque(StructType *Ty) { |
| assert(!Ty->isOpaque()); |
| NonOpaqueStructTypes.insert(Ty); |
| bool Removed = OpaqueStructTypes.erase(Ty); |
| (void)Removed; |
| assert(Removed); |
| } |
| |
| void IRMover::IdentifiedStructTypeSet::addOpaque(StructType *Ty) { |
| assert(Ty->isOpaque()); |
| OpaqueStructTypes.insert(Ty); |
| } |
| |
| StructType * |
| IRMover::IdentifiedStructTypeSet::findNonOpaque(ArrayRef<Type *> ETypes, |
| bool IsPacked) { |
| IRMover::StructTypeKeyInfo::KeyTy Key(ETypes, IsPacked); |
| auto I = NonOpaqueStructTypes.find_as(Key); |
| return I == NonOpaqueStructTypes.end() ? nullptr : *I; |
| } |
| |
| bool IRMover::IdentifiedStructTypeSet::hasType(StructType *Ty) { |
| if (Ty->isOpaque()) |
| return OpaqueStructTypes.count(Ty); |
| auto I = NonOpaqueStructTypes.find(Ty); |
| return I == NonOpaqueStructTypes.end() ? false : *I == Ty; |
| } |
| |
| IRMover::IRMover(Module &M) : Composite(M) { |
| TypeFinder StructTypes; |
| StructTypes.run(M, /* OnlyNamed */ false); |
| for (StructType *Ty : StructTypes) { |
| if (Ty->isOpaque()) |
| IdentifiedStructTypes.addOpaque(Ty); |
| else |
| IdentifiedStructTypes.addNonOpaque(Ty); |
| } |
| // Self-map metadatas in the destination module. This is needed when |
| // DebugTypeODRUniquing is enabled on the LLVMContext, since metadata in the |
| // destination module may be reached from the source module. |
| for (auto *MD : StructTypes.getVisitedMetadata()) { |
| SharedMDs[MD].reset(const_cast<MDNode *>(MD)); |
| } |
| } |
| |
| Error IRMover::move( |
| std::unique_ptr<Module> Src, ArrayRef<GlobalValue *> ValuesToLink, |
| std::function<void(GlobalValue &, ValueAdder Add)> AddLazyFor, |
| bool IsPerformingImport) { |
| IRLinker TheIRLinker(Composite, SharedMDs, IdentifiedStructTypes, |
| std::move(Src), ValuesToLink, std::move(AddLazyFor), |
| IsPerformingImport); |
| Error E = TheIRLinker.run(); |
| Composite.dropTriviallyDeadConstantArrays(); |
| return E; |
| } |