diff options
Diffstat (limited to 'contrib/llvm/lib/Linker/LinkModules.cpp')
| -rw-r--r-- | contrib/llvm/lib/Linker/LinkModules.cpp | 619 |
1 files changed, 422 insertions, 197 deletions
diff --git a/contrib/llvm/lib/Linker/LinkModules.cpp b/contrib/llvm/lib/Linker/LinkModules.cpp index 8f2200e..5bb2862 100644 --- a/contrib/llvm/lib/Linker/LinkModules.cpp +++ b/contrib/llvm/lib/Linker/LinkModules.cpp @@ -11,7 +11,7 @@ // //===----------------------------------------------------------------------===// -#include "llvm/Linker.h" +#include "llvm/Linker/Linker.h" #include "llvm-c/Linker.h" #include "llvm/ADT/Optional.h" #include "llvm/ADT/SetVector.h" @@ -19,12 +19,15 @@ #include "llvm/IR/Constants.h" #include "llvm/IR/Module.h" #include "llvm/IR/TypeFinder.h" +#include "llvm/Support/CommandLine.h" #include "llvm/Support/Debug.h" #include "llvm/Support/raw_ostream.h" #include "llvm/Transforms/Utils/Cloning.h" #include <cctype> +#include <tuple> using namespace llvm; + //===----------------------------------------------------------------------===// // TypeMap implementation. //===----------------------------------------------------------------------===// @@ -41,12 +44,12 @@ class TypeMapTy : public ValueMapTypeRemapper { /// we speculatively add types to MappedTypes, but keep track of them here in /// case we need to roll back. SmallVector<Type*, 16> SpeculativeTypes; - + /// SrcDefinitionsToResolve - 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; - + /// DstResolvedOpaqueTypes - This is the set of opaque types in the /// destination modules who are getting a body from the source module. SmallPtrSet<StructType*, 16> DstResolvedOpaqueTypes; @@ -63,7 +66,7 @@ public: /// linkDefinedTypeBodies - Produce a body for an opaque type in the dest /// module from a type definition in the source module. void linkDefinedTypeBodies(); - + /// get - Return the mapped type to use for the specified input type from the /// source module. Type *get(Type *SrcTy); @@ -85,10 +88,10 @@ public: private: Type *getImpl(Type *T); /// remapType - Implement the ValueMapTypeRemapper interface. - Type *remapType(Type *SrcTy) { + Type *remapType(Type *SrcTy) override { return get(SrcTy); } - + bool areTypesIsomorphic(Type *DstTy, Type *SrcTy); }; } @@ -96,12 +99,12 @@ private: void TypeMapTy::addTypeMapping(Type *DstTy, Type *SrcTy) { Type *&Entry = MappedTypes[SrcTy]; if (Entry) return; - + if (DstTy == SrcTy) { Entry = DstTy; return; } - + // Check to see if these types are recursively isomorphic and establish a // mapping between them if so. if (!areTypesIsomorphic(DstTy, SrcTy)) { @@ -130,7 +133,7 @@ bool TypeMapTy::areTypesIsomorphic(Type *DstTy, Type *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. @@ -156,18 +159,18 @@ bool TypeMapTy::areTypesIsomorphic(Type *DstTy, Type *SrcTy) { 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; @@ -193,7 +196,7 @@ bool TypeMapTy::areTypesIsomorphic(Type *DstTy, Type *SrcTy) { if (!areTypesIsomorphic(DstTy->getContainedType(i), SrcTy->getContainedType(i))) return false; - + // If everything seems to have lined up, then everything is great. return true; } @@ -203,31 +206,31 @@ bool TypeMapTy::areTypesIsomorphic(Type *DstTy, Type *SrcTy) { void TypeMapTy::linkDefinedTypeBodies() { SmallVector<Type*, 16> Elements; SmallString<16> TmpName; - + // Note that processing entries in this loop (calling 'get') can add new // entries to the SrcDefinitionsToResolve vector. while (!SrcDefinitionsToResolve.empty()) { StructType *SrcSTy = SrcDefinitionsToResolve.pop_back_val(); StructType *DstSTy = cast<StructType>(MappedTypes[SrcSTy]); - + // TypeMap is a many-to-one mapping, if there were multiple types that // provide a body for DstSTy then previous iterations of this loop may have // already handled it. Just ignore this case. if (!DstSTy->isOpaque()) continue; assert(!SrcSTy->isOpaque() && "Not resolving a definition?"); - + // 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] = getImpl(SrcSTy->getElementType(i)); - + DstSTy->setBody(Elements, SrcSTy->isPacked()); - + // If DstSTy has no name or has a longer name than STy, then viciously steal // STy's name. if (!SrcSTy->hasName()) continue; StringRef SrcName = SrcSTy->getName(); - + if (!DstSTy->hasName() || DstSTy->getName().size() > SrcName.size()) { TmpName.insert(TmpName.end(), SrcName.begin(), SrcName.end()); SrcSTy->setName(""); @@ -235,7 +238,7 @@ void TypeMapTy::linkDefinedTypeBodies() { TmpName.clear(); } } - + DstResolvedOpaqueTypes.clear(); } @@ -243,7 +246,7 @@ void TypeMapTy::linkDefinedTypeBodies() { /// source module. Type *TypeMapTy::get(Type *Ty) { Type *Result = getImpl(Ty); - + // If this caused a reference to any struct type, resolve it before returning. if (!SrcDefinitionsToResolve.empty()) linkDefinedTypeBodies(); @@ -255,7 +258,7 @@ Type *TypeMapTy::getImpl(Type *Ty) { // If we already have an entry for this type, return it. Type **Entry = &MappedTypes[Ty]; if (*Entry) return *Entry; - + // If this is not a named struct type, then just map all of the elements and // then rebuild the type from inside out. if (!isa<StructType>(Ty) || cast<StructType>(Ty)->isLiteral()) { @@ -263,7 +266,7 @@ Type *TypeMapTy::getImpl(Type *Ty) { // true for the anonymous {} struct, things like 'float', integers, etc. if (Ty->getNumContainedTypes() == 0) return *Entry = Ty; - + // Remap all of the elements, keeping track of whether any of them change. bool AnyChange = false; SmallVector<Type*, 4> ElementTypes; @@ -272,23 +275,23 @@ Type *TypeMapTy::getImpl(Type *Ty) { ElementTypes[i] = getImpl(Ty->getContainedType(i)); AnyChange |= ElementTypes[i] != Ty->getContainedType(i); } - + // If we found our type while recursively processing stuff, just use it. Entry = &MappedTypes[Ty]; if (*Entry) return *Entry; - + // If all of the element types mapped directly over, then the type is usable // as-is. if (!AnyChange) 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::VectorTyID: + case Type::VectorTyID: return *Entry = VectorType::get(ElementTypes[0], cast<VectorType>(Ty)->getNumElements()); case Type::PointerTyID: @@ -329,7 +332,7 @@ Type *TypeMapTy::getImpl(Type *Ty) { // and is not required for the prettiness of the linked module, we just skip // it and always rebuild a type here. StructType *STy = cast<StructType>(Ty); - + // If the type is opaque, we can just use it directly. if (STy->isOpaque()) { // A named structure type from src module is used. Add it to the Set of @@ -337,7 +340,7 @@ Type *TypeMapTy::getImpl(Type *Ty) { DstStructTypesSet.insert(STy); return *Entry = STy; } - + // Otherwise we create a new type and resolve its body later. This will be // resolved by the top level of get(). SrcDefinitionsToResolve.push_back(STy); @@ -370,15 +373,15 @@ namespace { LazilyLinkFunctions(LazilyLinkFunctions) { } - virtual Value *materializeValueFor(Value *V); + Value *materializeValueFor(Value *V) override; }; /// ModuleLinker - This is an implementation class for the LinkModules /// function, which is the entrypoint for this file. class ModuleLinker { Module *DstM, *SrcM; - - TypeMapTy TypeMap; + + TypeMapTy TypeMap; ValueMaterializerTy ValMaterializer; /// ValueMap - Mapping of values from what they used to be in Src, to what @@ -386,33 +389,36 @@ namespace { /// 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; - + struct AppendingVarInfo { GlobalVariable *NewGV; // New aggregate global in dest module. Constant *DstInit; // Old initializer from dest module. Constant *SrcInit; // Old initializer from src module. }; - + std::vector<AppendingVarInfo> AppendingVars; - + unsigned Mode; // Mode to treat source module. - + // Set of items not to link in from source. SmallPtrSet<const Value*, 16> DoNotLinkFromSource; - + // Vector of functions to lazily link in. std::vector<Function*> LazilyLinkFunctions; - + + bool SuppressWarnings; + public: std::string ErrorMsg; - - ModuleLinker(Module *dstM, TypeSet &Set, Module *srcM, unsigned mode) - : DstM(dstM), SrcM(srcM), TypeMap(Set), - ValMaterializer(TypeMap, DstM, LazilyLinkFunctions), - Mode(mode) { } - + + ModuleLinker(Module *dstM, TypeSet &Set, Module *srcM, unsigned mode, + bool SuppressWarnings=false) + : DstM(dstM), SrcM(srcM), TypeMap(Set), + ValMaterializer(TypeMap, DstM, LazilyLinkFunctions), Mode(mode), + SuppressWarnings(SuppressWarnings) {} + bool run(); - + private: /// emitError - Helper method for setting a message and returning an error /// code. @@ -420,7 +426,19 @@ namespace { ErrorMsg = Message.str(); return true; } - + + bool getComdatLeader(Module *M, StringRef ComdatName, + const GlobalVariable *&GVar); + bool computeResultingSelectionKind(StringRef ComdatName, + Comdat::SelectionKind Src, + Comdat::SelectionKind Dst, + Comdat::SelectionKind &Result, + bool &LinkFromSrc); + std::map<const Comdat *, std::pair<Comdat::SelectionKind, bool>> + ComdatsChosen; + bool getComdatResult(const Comdat *SrcC, Comdat::SelectionKind &SK, + bool &LinkFromSrc); + /// getLinkageResult - This analyzes the two global values and determines /// what the result will look like in the destination module. bool getLinkageResult(GlobalValue *Dest, const GlobalValue *Src, @@ -434,29 +452,29 @@ namespace { // 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 0; - + return nullptr; + // Otherwise see if we have a match in the destination module's symtab. GlobalValue *DGV = DstM->getNamedValue(SrcGV->getName()); - if (DGV == 0) return 0; - + 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 0; + return nullptr; // Otherwise, we do in fact link to the destination global. return DGV; } - + void computeTypeMapping(); - + bool linkAppendingVarProto(GlobalVariable *DstGV, GlobalVariable *SrcGV); bool linkGlobalProto(GlobalVariable *SrcGV); bool linkFunctionProto(Function *SrcF); bool linkAliasProto(GlobalAlias *SrcA); bool linkModuleFlagsMetadata(); - + void linkAppendingVarInit(const AppendingVarInfo &AVI); void linkGlobalInits(); void linkFunctionBody(Function *Dst, Function *Src); @@ -490,10 +508,16 @@ static void forceRenaming(GlobalValue *GV, StringRef Name) { /// a GlobalValue) from the SrcGV to the DestGV. static void copyGVAttributes(GlobalValue *DestGV, const GlobalValue *SrcGV) { // Use the maximum alignment, rather than just copying the alignment of SrcGV. - unsigned Alignment = std::max(DestGV->getAlignment(), SrcGV->getAlignment()); + auto *DestGO = dyn_cast<GlobalObject>(DestGV); + unsigned Alignment; + if (DestGO) + Alignment = std::max(DestGO->getAlignment(), SrcGV->getAlignment()); + DestGV->copyAttributesFrom(SrcGV); - DestGV->setAlignment(Alignment); - + + if (DestGO) + DestGO->setAlignment(Alignment); + forceRenaming(DestGV, SrcGV->getName()); } @@ -513,7 +537,7 @@ static bool isLessConstraining(GlobalValue::VisibilityTypes a, Value *ValueMaterializerTy::materializeValueFor(Value *V) { Function *SF = dyn_cast<Function>(V); if (!SF) - return NULL; + return nullptr; Function *DF = Function::Create(TypeMap.get(SF->getFunctionType()), SF->getLinkage(), SF->getName(), DstM); @@ -523,6 +547,115 @@ Value *ValueMaterializerTy::materializeValueFor(Value *V) { return DF; } +bool ModuleLinker::getComdatLeader(Module *M, StringRef ComdatName, + const GlobalVariable *&GVar) { + const GlobalValue *GVal = M->getNamedValue(ComdatName); + if (const auto *GA = dyn_cast_or_null<GlobalAlias>(GVal)) { + GVal = GA->getBaseObject(); + if (!GVal) + // We cannot resolve the size of the aliasee yet. + return emitError("Linking COMDATs named '" + ComdatName + + "': COMDAT key involves incomputable alias size."); + } + + GVar = dyn_cast_or_null<GlobalVariable>(GVal); + if (!GVar) + return emitError( + "Linking COMDATs named '" + ComdatName + + "': GlobalVariable required for data dependent selection!"); + + return false; +} + +bool ModuleLinker::computeResultingSelectionKind(StringRef ComdatName, + Comdat::SelectionKind Src, + Comdat::SelectionKind Dst, + Comdat::SelectionKind &Result, + bool &LinkFromSrc) { + // The ability to mix Comdat::SelectionKind::Any with + // Comdat::SelectionKind::Largest is a behavior that comes from COFF. + bool DstAnyOrLargest = Dst == Comdat::SelectionKind::Any || + Dst == Comdat::SelectionKind::Largest; + bool SrcAnyOrLargest = Src == Comdat::SelectionKind::Any || + Src == Comdat::SelectionKind::Largest; + if (DstAnyOrLargest && SrcAnyOrLargest) { + if (Dst == Comdat::SelectionKind::Largest || + Src == Comdat::SelectionKind::Largest) + Result = Comdat::SelectionKind::Largest; + else + Result = Comdat::SelectionKind::Any; + } else if (Src == Dst) { + Result = Dst; + } else { + return emitError("Linking COMDATs named '" + ComdatName + + "': invalid selection kinds!"); + } + + switch (Result) { + case Comdat::SelectionKind::Any: + // Go with Dst. + LinkFromSrc = false; + break; + case Comdat::SelectionKind::NoDuplicates: + return emitError("Linking COMDATs named '" + ComdatName + + "': noduplicates has been violated!"); + case Comdat::SelectionKind::ExactMatch: + case Comdat::SelectionKind::Largest: + case Comdat::SelectionKind::SameSize: { + const GlobalVariable *DstGV; + const GlobalVariable *SrcGV; + if (getComdatLeader(DstM, ComdatName, DstGV) || + getComdatLeader(SrcM, ComdatName, SrcGV)) + return true; + + const DataLayout *DstDL = DstM->getDataLayout(); + const DataLayout *SrcDL = SrcM->getDataLayout(); + if (!DstDL || !SrcDL) { + return emitError( + "Linking COMDATs named '" + ComdatName + + "': can't do size dependent selection without DataLayout!"); + } + uint64_t DstSize = + DstDL->getTypeAllocSize(DstGV->getType()->getPointerElementType()); + uint64_t SrcSize = + SrcDL->getTypeAllocSize(SrcGV->getType()->getPointerElementType()); + if (Result == Comdat::SelectionKind::ExactMatch) { + if (SrcGV->getInitializer() != DstGV->getInitializer()) + return emitError("Linking COMDATs named '" + ComdatName + + "': ExactMatch violated!"); + LinkFromSrc = false; + } else if (Result == Comdat::SelectionKind::Largest) { + LinkFromSrc = SrcSize > DstSize; + } else if (Result == Comdat::SelectionKind::SameSize) { + if (SrcSize != DstSize) + return emitError("Linking COMDATs named '" + ComdatName + + "': SameSize violated!"); + LinkFromSrc = false; + } else { + llvm_unreachable("unknown selection kind"); + } + break; + } + } + + return false; +} + +bool ModuleLinker::getComdatResult(const Comdat *SrcC, + Comdat::SelectionKind &Result, + bool &LinkFromSrc) { + StringRef ComdatName = SrcC->getName(); + Module::ComdatSymTabType &ComdatSymTab = DstM->getComdatSymbolTable(); + Module::ComdatSymTabType::iterator DstCI = ComdatSymTab.find(ComdatName); + if (DstCI != ComdatSymTab.end()) { + const Comdat *DstC = &DstCI->second; + Comdat::SelectionKind SSK = SrcC->getSelectionKind(); + Comdat::SelectionKind DSK = DstC->getSelectionKind(); + if (computeResultingSelectionKind(ComdatName, SSK, DSK, Result, LinkFromSrc)) + return true; + } + return false; +} /// getLinkageResult - This analyzes the two global values and determines what /// the result will look like in the destination module. In particular, it @@ -536,15 +669,15 @@ bool ModuleLinker::getLinkageResult(GlobalValue *Dest, const GlobalValue *Src, assert(Dest && "Must have two globals being queried"); assert(!Src->hasLocalLinkage() && "If Src has internal linkage, Dest shouldn't be set!"); - + bool SrcIsDeclaration = Src->isDeclaration() && !Src->isMaterializable(); bool DestIsDeclaration = Dest->isDeclaration(); - + if (SrcIsDeclaration) { // If Src is external or if both Src & Dest are external.. Just link the // external globals, we aren't adding anything. - if (Src->hasDLLImportLinkage()) { - // If one of GVs has DLLImport linkage, result should be dllimport'ed. + if (Src->hasDLLImportStorageClass()) { + // If one of GVs is marked as DLLImport, result should be dllimport'ed. if (DestIsDeclaration) { LinkFromSrc = true; LT = Src->getLinkage(); @@ -557,7 +690,7 @@ bool ModuleLinker::getLinkageResult(GlobalValue *Dest, const GlobalValue *Src, LinkFromSrc = false; LT = Dest->getLinkage(); } - } else if (DestIsDeclaration && !Dest->hasDLLImportLinkage()) { + } else if (DestIsDeclaration && !Dest->hasDLLImportStorageClass()) { // If Dest is external but Src is not: LinkFromSrc = true; LT = Src->getLinkage(); @@ -584,10 +717,8 @@ bool ModuleLinker::getLinkageResult(GlobalValue *Dest, const GlobalValue *Src, LT = GlobalValue::ExternalLinkage; } } else { - assert((Dest->hasExternalLinkage() || Dest->hasDLLImportLinkage() || - Dest->hasDLLExportLinkage() || Dest->hasExternalWeakLinkage()) && - (Src->hasExternalLinkage() || Src->hasDLLImportLinkage() || - Src->hasDLLExportLinkage() || Src->hasExternalWeakLinkage()) && + assert((Dest->hasExternalLinkage() || Dest->hasExternalWeakLinkage()) && + (Src->hasExternalLinkage() || Src->hasExternalWeakLinkage()) && "Unexpected linkage type!"); return emitError("Linking globals named '" + Src->getName() + "': symbol multiply defined!"); @@ -595,6 +726,8 @@ bool ModuleLinker::getLinkageResult(GlobalValue *Dest, const GlobalValue *Src, // Compute the visibility. We follow the rules in the System V Application // Binary Interface. + assert(!GlobalValue::isLocalLinkage(LT) && + "Symbols with local linkage should not be merged"); Vis = isLessConstraining(Src->getVisibility(), Dest->getVisibility()) ? Dest->getVisibility() : Src->getVisibility(); return false; @@ -609,19 +742,19 @@ void ModuleLinker::computeTypeMapping() { for (Module::global_iterator I = SrcM->global_begin(), E = SrcM->global_end(); I != E; ++I) { GlobalValue *DGV = getLinkedToGlobal(I); - if (DGV == 0) continue; - + if (!DGV) continue; + if (!DGV->hasAppendingLinkage() || !I->hasAppendingLinkage()) { TypeMap.addTypeMapping(DGV->getType(), I->getType()); - continue; + continue; } - + // Unify the element type of appending arrays. ArrayType *DAT = cast<ArrayType>(DGV->getType()->getElementType()); ArrayType *SAT = cast<ArrayType>(I->getType()->getElementType()); TypeMap.addTypeMapping(DAT->getElementType(), SAT->getElementType()); } - + // Incorporate functions. for (Module::iterator I = SrcM->begin(), E = SrcM->end(); I != E; ++I) { if (GlobalValue *DGV = getLinkedToGlobal(I)) @@ -640,14 +773,14 @@ void ModuleLinker::computeTypeMapping() { for (unsigned i = 0, e = SrcStructTypes.size(); i != e; ++i) { StructType *ST = SrcStructTypes[i]; if (!ST->hasName()) continue; - + // Check to see if there is a dot in the name followed by a digit. size_t DotPos = ST->getName().rfind('.'); if (DotPos == 0 || DotPos == StringRef::npos || ST->getName().back() == '.' || !isdigit(static_cast<unsigned char>(ST->getName()[DotPos+1]))) continue; - + // Check to see if the destination module has a struct with the prefix name. if (StructType *DST = DstM->getTypeByName(ST->getName().substr(0, DotPos))) // Don't use it if this actually came from the source module. They're in @@ -672,9 +805,9 @@ void ModuleLinker::computeTypeMapping() { } // Don't bother incorporating aliases, they aren't generally typed well. - + // 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. + // any 'opaque' types in the dest module that are now resolved. TypeMap.linkDefinedTypeBodies(); } @@ -682,26 +815,26 @@ void ModuleLinker::computeTypeMapping() { /// them together now. Return true on error. bool ModuleLinker::linkAppendingVarProto(GlobalVariable *DstGV, GlobalVariable *SrcGV) { - + if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage()) return emitError("Linking globals named '" + SrcGV->getName() + "': can only link appending global with another appending global!"); - + ArrayType *DstTy = cast<ArrayType>(DstGV->getType()->getElementType()); ArrayType *SrcTy = cast<ArrayType>(TypeMap.get(SrcGV->getType()->getElementType())); Type *EltTy = DstTy->getElementType(); - + // Check to see that they two arrays agree on type. if (EltTy != SrcTy->getElementType()) return emitError("Appending variables with different element types!"); if (DstGV->isConstant() != SrcGV->isConstant()) return emitError("Appending variables linked with different const'ness!"); - + if (DstGV->getAlignment() != SrcGV->getAlignment()) return emitError( "Appending variables with different alignment need to be linked!"); - + if (DstGV->getVisibility() != SrcGV->getVisibility()) return emitError( "Appending variables with different visibility need to be linked!"); @@ -710,23 +843,23 @@ bool ModuleLinker::linkAppendingVarProto(GlobalVariable *DstGV, return emitError( "Appending variables with different unnamed_addr need to be linked!"); - if (DstGV->getSection() != SrcGV->getSection()) + if (StringRef(DstGV->getSection()) != SrcGV->getSection()) return emitError( "Appending variables with different section name need to be linked!"); - + uint64_t NewSize = DstTy->getNumElements() + SrcTy->getNumElements(); ArrayType *NewType = ArrayType::get(EltTy, NewSize); - + // Create the new global variable. GlobalVariable *NG = new GlobalVariable(*DstGV->getParent(), NewType, SrcGV->isConstant(), - DstGV->getLinkage(), /*init*/0, /*name*/"", DstGV, + DstGV->getLinkage(), /*init*/nullptr, /*name*/"", DstGV, DstGV->getThreadLocalMode(), DstGV->getType()->getAddressSpace()); - + // Propagate alignment, visibility and section info. copyGVAttributes(NG, DstGV); - + AppendingVarInfo AVI; AVI.NewGV = NG; AVI.DstInit = DstGV->getInitializer(); @@ -739,10 +872,10 @@ bool ModuleLinker::linkAppendingVarProto(GlobalVariable *DstGV, DstGV->replaceAllUsesWith(ConstantExpr::getBitCast(NG, DstGV->getType())); DstGV->eraseFromParent(); - + // Track the source variable so we don't try to link it. DoNotLinkFromSource.insert(SrcGV); - + return false; } @@ -753,52 +886,71 @@ bool ModuleLinker::linkGlobalProto(GlobalVariable *SGV) { llvm::Optional<GlobalValue::VisibilityTypes> NewVisibility; bool HasUnnamedAddr = SGV->hasUnnamedAddr(); + bool LinkFromSrc = false; + Comdat *DC = nullptr; + if (const Comdat *SC = SGV->getComdat()) { + Comdat::SelectionKind SK; + std::tie(SK, LinkFromSrc) = ComdatsChosen[SC]; + DC = DstM->getOrInsertComdat(SC->getName()); + DC->setSelectionKind(SK); + } + if (DGV) { - // Concatenation of appending linkage variables is magic and handled later. - if (DGV->hasAppendingLinkage() || SGV->hasAppendingLinkage()) - return linkAppendingVarProto(cast<GlobalVariable>(DGV), SGV); - - // Determine whether linkage of these two globals follows the source - // module's definition or the destination module's definition. - GlobalValue::LinkageTypes NewLinkage = GlobalValue::InternalLinkage; - GlobalValue::VisibilityTypes NV; - bool LinkFromSrc = false; - if (getLinkageResult(DGV, SGV, NewLinkage, NV, LinkFromSrc)) - return true; - NewVisibility = NV; - HasUnnamedAddr = HasUnnamedAddr && DGV->hasUnnamedAddr(); + if (!DC) { + // Concatenation of appending linkage variables is magic and handled later. + if (DGV->hasAppendingLinkage() || SGV->hasAppendingLinkage()) + return linkAppendingVarProto(cast<GlobalVariable>(DGV), SGV); + + // Determine whether linkage of these two globals follows the source + // module's definition or the destination module's definition. + GlobalValue::LinkageTypes NewLinkage = GlobalValue::InternalLinkage; + GlobalValue::VisibilityTypes NV; + if (getLinkageResult(DGV, SGV, NewLinkage, NV, LinkFromSrc)) + return true; + NewVisibility = NV; + HasUnnamedAddr = HasUnnamedAddr && DGV->hasUnnamedAddr(); + + // If we're not linking from the source, then keep the definition that we + // have. + if (!LinkFromSrc) { + // Special case for const propagation. + if (GlobalVariable *DGVar = dyn_cast<GlobalVariable>(DGV)) + if (DGVar->isDeclaration() && SGV->isConstant() && + !DGVar->isConstant()) + DGVar->setConstant(true); + + // Set calculated linkage, visibility and unnamed_addr. + DGV->setLinkage(NewLinkage); + DGV->setVisibility(*NewVisibility); + DGV->setUnnamedAddr(HasUnnamedAddr); + } + } - // If we're not linking from the source, then keep the definition that we - // have. if (!LinkFromSrc) { - // Special case for const propagation. - if (GlobalVariable *DGVar = dyn_cast<GlobalVariable>(DGV)) - if (DGVar->isDeclaration() && SGV->isConstant() && !DGVar->isConstant()) - DGVar->setConstant(true); - - // Set calculated linkage, visibility and unnamed_addr. - DGV->setLinkage(NewLinkage); - DGV->setVisibility(*NewVisibility); - DGV->setUnnamedAddr(HasUnnamedAddr); - // Make sure to remember this mapping. ValueMap[SGV] = ConstantExpr::getBitCast(DGV,TypeMap.get(SGV->getType())); - - // Track the source global so that we don't attempt to copy it over when + + // Track the source global so that we don't attempt to copy it over when // processing global initializers. DoNotLinkFromSource.insert(SGV); - + return false; } } - + + // If the Comdat this variable was inside of wasn't selected, skip it. + if (DC && !DGV && !LinkFromSrc) { + DoNotLinkFromSource.insert(SGV); + return false; + } + // 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(SGV->getType()->getElementType()), - SGV->isConstant(), SGV->getLinkage(), /*init*/0, - SGV->getName(), /*insertbefore*/0, + SGV->isConstant(), SGV->getLinkage(), /*init*/nullptr, + SGV->getName(), /*insertbefore*/nullptr, SGV->getThreadLocalMode(), SGV->getType()->getAddressSpace()); // Propagate alignment, visibility and section info. @@ -807,11 +959,14 @@ bool ModuleLinker::linkGlobalProto(GlobalVariable *SGV) { NewDGV->setVisibility(*NewVisibility); NewDGV->setUnnamedAddr(HasUnnamedAddr); + if (DC) + NewDGV->setComdat(DC); + if (DGV) { DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewDGV, DGV->getType())); DGV->eraseFromParent(); } - + // Make sure to remember this mapping. ValueMap[SGV] = NewDGV; return false; @@ -824,32 +979,44 @@ bool ModuleLinker::linkFunctionProto(Function *SF) { llvm::Optional<GlobalValue::VisibilityTypes> NewVisibility; bool HasUnnamedAddr = SF->hasUnnamedAddr(); + bool LinkFromSrc = false; + Comdat *DC = nullptr; + if (const Comdat *SC = SF->getComdat()) { + Comdat::SelectionKind SK; + std::tie(SK, LinkFromSrc) = ComdatsChosen[SC]; + DC = DstM->getOrInsertComdat(SC->getName()); + DC->setSelectionKind(SK); + } + if (DGV) { - GlobalValue::LinkageTypes NewLinkage = GlobalValue::InternalLinkage; - bool LinkFromSrc = false; - GlobalValue::VisibilityTypes NV; - if (getLinkageResult(DGV, SF, NewLinkage, NV, LinkFromSrc)) - return true; - NewVisibility = NV; - HasUnnamedAddr = HasUnnamedAddr && DGV->hasUnnamedAddr(); + if (!DC) { + GlobalValue::LinkageTypes NewLinkage = GlobalValue::InternalLinkage; + GlobalValue::VisibilityTypes NV; + if (getLinkageResult(DGV, SF, NewLinkage, NV, LinkFromSrc)) + return true; + NewVisibility = NV; + HasUnnamedAddr = HasUnnamedAddr && DGV->hasUnnamedAddr(); + + if (!LinkFromSrc) { + // Set calculated linkage + DGV->setLinkage(NewLinkage); + DGV->setVisibility(*NewVisibility); + DGV->setUnnamedAddr(HasUnnamedAddr); + } + } if (!LinkFromSrc) { - // Set calculated linkage - DGV->setLinkage(NewLinkage); - DGV->setVisibility(*NewVisibility); - DGV->setUnnamedAddr(HasUnnamedAddr); - // Make sure to remember this mapping. ValueMap[SF] = ConstantExpr::getBitCast(DGV, TypeMap.get(SF->getType())); - - // Track the function from the source module so we don't attempt to remap + + // Track the function from the source module so we don't attempt to remap // it. DoNotLinkFromSource.insert(SF); - + return false; } } - + // If the function is to be lazily linked, don't create it just yet. // The ValueMaterializerTy will deal with creating it if it's used. if (!DGV && (SF->hasLocalLinkage() || SF->hasLinkOnceLinkage() || @@ -858,6 +1025,12 @@ bool ModuleLinker::linkFunctionProto(Function *SF) { return false; } + // If the Comdat this function was inside of wasn't selected, skip it. + if (DC && !DGV && !LinkFromSrc) { + DoNotLinkFromSource.insert(SF); + return false; + } + // If there is no linkage to be performed or we are linking from the source, // bring SF over. Function *NewDF = Function::Create(TypeMap.get(SF->getFunctionType()), @@ -867,12 +1040,15 @@ bool ModuleLinker::linkFunctionProto(Function *SF) { NewDF->setVisibility(*NewVisibility); NewDF->setUnnamedAddr(HasUnnamedAddr); + if (DC) + NewDF->setComdat(DC); + if (DGV) { // Any uses of DF need to change to NewDF, with cast. DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewDF, DGV->getType())); DGV->eraseFromParent(); } - + ValueMap[SF] = NewDF; return false; } @@ -882,45 +1058,68 @@ bool ModuleLinker::linkFunctionProto(Function *SF) { bool ModuleLinker::linkAliasProto(GlobalAlias *SGA) { GlobalValue *DGV = getLinkedToGlobal(SGA); llvm::Optional<GlobalValue::VisibilityTypes> NewVisibility; + bool HasUnnamedAddr = SGA->hasUnnamedAddr(); + + bool LinkFromSrc = false; + Comdat *DC = nullptr; + if (const Comdat *SC = SGA->getComdat()) { + Comdat::SelectionKind SK; + std::tie(SK, LinkFromSrc) = ComdatsChosen[SC]; + DC = DstM->getOrInsertComdat(SC->getName()); + DC->setSelectionKind(SK); + } if (DGV) { - GlobalValue::LinkageTypes NewLinkage = GlobalValue::InternalLinkage; - GlobalValue::VisibilityTypes NV; - bool LinkFromSrc = false; - if (getLinkageResult(DGV, SGA, NewLinkage, NV, LinkFromSrc)) - return true; - NewVisibility = NV; + if (!DC) { + GlobalValue::LinkageTypes NewLinkage = GlobalValue::InternalLinkage; + GlobalValue::VisibilityTypes NV; + if (getLinkageResult(DGV, SGA, NewLinkage, NV, LinkFromSrc)) + return true; + NewVisibility = NV; + HasUnnamedAddr = HasUnnamedAddr && DGV->hasUnnamedAddr(); + + if (!LinkFromSrc) { + // Set calculated linkage. + DGV->setLinkage(NewLinkage); + DGV->setVisibility(*NewVisibility); + DGV->setUnnamedAddr(HasUnnamedAddr); + } + } if (!LinkFromSrc) { - // Set calculated linkage. - DGV->setLinkage(NewLinkage); - DGV->setVisibility(*NewVisibility); - // Make sure to remember this mapping. ValueMap[SGA] = ConstantExpr::getBitCast(DGV,TypeMap.get(SGA->getType())); - + // Track the alias from the source module so we don't attempt to remap it. DoNotLinkFromSource.insert(SGA); - + return false; } } - + + // If the Comdat this alias was inside of wasn't selected, skip it. + if (DC && !DGV && !LinkFromSrc) { + DoNotLinkFromSource.insert(SGA); + return false; + } + // If there is no linkage to be performed or we're linking from the source, // bring over SGA. - GlobalAlias *NewDA = new GlobalAlias(TypeMap.get(SGA->getType()), - SGA->getLinkage(), SGA->getName(), - /*aliasee*/0, DstM); + auto *PTy = cast<PointerType>(TypeMap.get(SGA->getType())); + auto *NewDA = + GlobalAlias::create(PTy->getElementType(), PTy->getAddressSpace(), + SGA->getLinkage(), SGA->getName(), DstM); copyGVAttributes(NewDA, SGA); if (NewVisibility) NewDA->setVisibility(*NewVisibility); + NewDA->setUnnamedAddr(HasUnnamedAddr); if (DGV) { // Any uses of DGV need to change to NewDA, with cast. DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewDA, DGV->getType())); DGV->eraseFromParent(); } - + ValueMap[SGA] = NewDA; return false; } @@ -931,15 +1130,15 @@ static void getArrayElements(Constant *C, SmallVectorImpl<Constant*> &Dest) { for (unsigned i = 0; i != NumElements; ++i) Dest.push_back(C->getAggregateElement(i)); } - + void ModuleLinker::linkAppendingVarInit(const AppendingVarInfo &AVI) { // Merge the initializer. SmallVector<Constant*, 16> Elements; getArrayElements(AVI.DstInit, Elements); - + Constant *SrcInit = MapValue(AVI.SrcInit, ValueMap, RF_None, &TypeMap, &ValMaterializer); getArrayElements(SrcInit, Elements); - + ArrayType *NewType = cast<ArrayType>(AVI.NewGV->getType()->getElementType()); AVI.NewGV->setInitializer(ConstantArray::get(NewType, Elements)); } @@ -950,10 +1149,10 @@ void ModuleLinker::linkGlobalInits() { // Loop over all of the globals in the src module, mapping them over as we go for (Module::const_global_iterator I = SrcM->global_begin(), E = SrcM->global_end(); I != E; ++I) { - + // Only process initialized GV's or ones not already in dest. - if (!I->hasInitializer() || DoNotLinkFromSource.count(I)) continue; - + if (!I->hasInitializer() || DoNotLinkFromSource.count(I)) continue; + // Grab destination global variable. GlobalVariable *DGV = cast<GlobalVariable>(ValueMap[I]); // Figure out what the initializer looks like in the dest module. @@ -981,7 +1180,7 @@ void ModuleLinker::linkFunctionBody(Function *Dst, Function *Src) { if (Mode == Linker::DestroySource) { // Splice the body of the source function into the dest function. Dst->getBasicBlockList().splice(Dst->end(), Src->getBasicBlockList()); - + // At this point, all of the instructions and values of the function are now // copied over. The only problem is that they are still referencing values in // the Source function as operands. Loop through all of the operands of the @@ -990,19 +1189,19 @@ void ModuleLinker::linkFunctionBody(Function *Dst, Function *Src) { for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I) RemapInstruction(I, ValueMap, RF_IgnoreMissingEntries, &TypeMap, &ValMaterializer); - + } else { // Clone the body of the function into the dest function. SmallVector<ReturnInst*, 8> Returns; // Ignore returns. - CloneFunctionInto(Dst, Src, ValueMap, false, Returns, "", NULL, + CloneFunctionInto(Dst, Src, ValueMap, false, Returns, "", nullptr, &TypeMap, &ValMaterializer); } - + // There is no need to map the arguments anymore. for (Function::arg_iterator I = Src->arg_begin(), E = Src->arg_end(); I != E; ++I) ValueMap.erase(I); - + } /// linkAliasBodies - Insert all of the aliases in Src into the Dest module. @@ -1013,8 +1212,9 @@ void ModuleLinker::linkAliasBodies() { continue; if (Constant *Aliasee = I->getAliasee()) { GlobalAlias *DA = cast<GlobalAlias>(ValueMap[I]); - DA->setAliasee(MapValue(Aliasee, ValueMap, RF_None, - &TypeMap, &ValMaterializer)); + Constant *Val = + MapValue(Aliasee, ValueMap, RF_None, &TypeMap, &ValMaterializer); + DA->setAliasee(Val); } } } @@ -1124,7 +1324,7 @@ bool ModuleLinker::linkModuleFlagsMetadata() { // Perform the merge for standard behavior types. switch (SrcBehaviorValue) { case Module::Require: - case Module::Override: assert(0 && "not possible"); break; + case Module::Override: llvm_unreachable("not possible"); case Module::Error: { // Emit an error if the values differ. if (SrcOp->getOperand(2) != DstOp->getOperand(2)) { @@ -1136,8 +1336,10 @@ bool ModuleLinker::linkModuleFlagsMetadata() { case Module::Warning: { // Emit a warning if the values differ. if (SrcOp->getOperand(2) != DstOp->getOperand(2)) { - errs() << "WARNING: linking module flags '" << ID->getString() - << "': IDs have conflicting values"; + if (!SuppressWarnings) { + errs() << "WARNING: linking module flags '" << ID->getString() + << "': IDs have conflicting values"; + } } continue; } @@ -1188,30 +1390,39 @@ bool ModuleLinker::linkModuleFlagsMetadata() { return HasErr; } - + bool ModuleLinker::run() { assert(DstM && "Null destination module"); assert(SrcM && "Null source module"); // Inherit the target data from the source module if the destination module // doesn't have one already. - if (DstM->getDataLayout().empty() && !SrcM->getDataLayout().empty()) + if (!DstM->getDataLayout() && SrcM->getDataLayout()) 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()); - if (!SrcM->getDataLayout().empty() && !DstM->getDataLayout().empty() && - SrcM->getDataLayout() != DstM->getDataLayout()) - errs() << "WARNING: Linking two modules of different data layouts!\n"; + if (SrcM->getDataLayout() && DstM->getDataLayout() && + *SrcM->getDataLayout() != *DstM->getDataLayout()) { + if (!SuppressWarnings) { + errs() << "WARNING: Linking two modules of different data layouts: '" + << SrcM->getModuleIdentifier() << "' is '" + << SrcM->getDataLayoutStr() << "' whereas '" + << DstM->getModuleIdentifier() << "' is '" + << DstM->getDataLayoutStr() << "'\n"; + } + } if (!SrcM->getTargetTriple().empty() && DstM->getTargetTriple() != SrcM->getTargetTriple()) { - errs() << "WARNING: Linking two modules of different target triples: "; - if (!SrcM->getModuleIdentifier().empty()) - errs() << SrcM->getModuleIdentifier() << ": "; - errs() << "'" << SrcM->getTargetTriple() << "' and '" - << DstM->getTargetTriple() << "'\n"; + if (!SuppressWarnings) { + errs() << "WARNING: Linking two modules of different target triples: " + << SrcM->getModuleIdentifier() << "' is '" + << SrcM->getTargetTriple() << "' whereas '" + << DstM->getModuleIdentifier() << "' is '" + << DstM->getTargetTriple() << "'\n"; + } } // Append the module inline asm string. @@ -1226,6 +1437,18 @@ bool ModuleLinker::run() { // Loop over all of the linked values to compute type mappings. computeTypeMapping(); + ComdatsChosen.clear(); + for (const StringMapEntry<llvm::Comdat> &SMEC : SrcM->getComdatSymbolTable()) { + const Comdat &C = SMEC.getValue(); + if (ComdatsChosen.count(&C)) + continue; + Comdat::SelectionKind SK; + bool LinkFromSrc; + if (getComdatResult(&C, SK, LinkFromSrc)) + return true; + ComdatsChosen[&C] = std::make_pair(SK, LinkFromSrc); + } + // Insert all of the globals in src into the DstM module... without linking // initializers (which could refer to functions not yet mapped over). for (Module::global_iterator I = SrcM->global_begin(), @@ -1250,17 +1473,13 @@ bool ModuleLinker::run() { for (unsigned i = 0, e = AppendingVars.size(); i != e; ++i) linkAppendingVarInit(AppendingVars[i]); - - // Update the initializers in the DstM module now that all globals that may - // be referenced are in DstM. - linkGlobalInits(); // Link in the function bodies that are defined in the source module into // DstM. for (Module::iterator SF = SrcM->begin(), E = SrcM->end(); SF != E; ++SF) { // Skip if not linking from source. if (DoNotLinkFromSource.count(SF)) continue; - + Function *DF = cast<Function>(ValueMap[SF]); if (SF->hasPrefixData()) { // Link in the prefix data. @@ -1275,7 +1494,7 @@ bool ModuleLinker::run() { if (SF->Materialize(&ErrorMsg)) return true; } - + linkFunctionBody(DF, SF); SF->Dematerialize(); } @@ -1292,13 +1511,17 @@ bool ModuleLinker::run() { if (linkModuleFlagsMetadata()) return true; + // Update the initializers in the DstM module now that all globals that may + // be referenced are in DstM. + linkGlobalInits(); + // Process vector of lazily linked in functions. bool LinkedInAnyFunctions; do { LinkedInAnyFunctions = false; - + for(std::vector<Function*>::iterator I = LazilyLinkFunctions.begin(), - E = LazilyLinkFunctions.end(); I != E; ++I) { + E = LazilyLinkFunctions.end(); I != E; ++I) { Function *SF = *I; if (!SF) continue; @@ -1320,7 +1543,7 @@ bool ModuleLinker::run() { if (SF->Materialize(&ErrorMsg)) return true; } - + // Erase from vector *before* the function body is linked - linkFunctionBody could // invalidate I. LazilyLinkFunctions.erase(I); @@ -1335,15 +1558,16 @@ bool ModuleLinker::run() { break; } } while (LinkedInAnyFunctions); - + // Now that all of the types from the source are used, resolve any structs // copied over to the dest that didn't exist there. TypeMap.linkDefinedTypeBodies(); - + return false; } -Linker::Linker(Module *M) : Composite(M) { +Linker::Linker(Module *M, bool SuppressWarnings) + : Composite(M), SuppressWarnings(SuppressWarnings) { TypeFinder StructTypes; StructTypes.run(*M, true); IdentifiedStructTypes.insert(StructTypes.begin(), StructTypes.end()); @@ -1354,11 +1578,12 @@ Linker::~Linker() { void Linker::deleteModule() { delete Composite; - Composite = NULL; + Composite = nullptr; } bool Linker::linkInModule(Module *Src, unsigned Mode, std::string *ErrorMsg) { - ModuleLinker TheLinker(Composite, IdentifiedStructTypes, Src, Mode); + ModuleLinker TheLinker(Composite, IdentifiedStructTypes, Src, Mode, + SuppressWarnings); if (TheLinker.run()) { if (ErrorMsg) *ErrorMsg = TheLinker.ErrorMsg; @@ -1376,7 +1601,7 @@ bool Linker::linkInModule(Module *Src, unsigned Mode, std::string *ErrorMsg) { /// error occurs, true is returned and ErrorMsg (if not null) is set to indicate /// the problem. Upon failure, the Dest module could be in a modified state, /// and shouldn't be relied on to be consistent. -bool Linker::LinkModules(Module *Dest, Module *Src, unsigned Mode, +bool Linker::LinkModules(Module *Dest, Module *Src, unsigned Mode, std::string *ErrorMsg) { Linker L(Dest); return L.linkInModule(Src, Mode, ErrorMsg); @@ -1390,7 +1615,7 @@ LLVMBool LLVMLinkModules(LLVMModuleRef Dest, LLVMModuleRef Src, LLVMLinkerMode Mode, char **OutMessages) { std::string Messages; LLVMBool Result = Linker::LinkModules(unwrap(Dest), unwrap(Src), - Mode, OutMessages? &Messages : 0); + Mode, OutMessages? &Messages : nullptr); if (OutMessages) *OutMessages = strdup(Messages.c_str()); return Result; |
