#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/TypeFinder.h"
#include "llvm/Transforms/Utils/Cloning.h"
using namespace llvm;
namespace {
class TypeMapTy : public ValueMapTypeRemapper {
DenseMap<Type *, Type *> MappedTypes;
SmallVector<Type *, 16> SpeculativeTypes;
SmallVector<StructType *, 16> SpeculativeDstOpaqueTypes;
SmallVector<StructType *, 16> SrcDefinitionsToResolve;
SmallPtrSet<StructType *, 16> DstResolvedOpaqueTypes;
public:
TypeMapTy(IRMover::IdentifiedStructTypeSet &DstStructTypesSet)
: DstStructTypesSet(DstStructTypesSet) {}
IRMover::IdentifiedStructTypeSet &DstStructTypesSet;
void addTypeMapping(Type *DstTy, Type *SrcTy);
void linkDefinedTypeBodies();
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());
if (!areTypesIsomorphic(DstTy, SrcTy)) {
for (Type *Ty : SpeculativeTypes)
MappedTypes.erase(Ty);
SrcDefinitionsToResolve.resize(SrcDefinitionsToResolve.size() -
SpeculativeDstOpaqueTypes.size());
for (StructType *Ty : SpeculativeDstOpaqueTypes)
DstResolvedOpaqueTypes.erase(Ty);
} else {
for (Type *Ty : SpeculativeTypes)
if (auto *STy = dyn_cast<StructType>(Ty))
if (STy->hasName())
STy->setName("");
}
SpeculativeTypes.clear();
SpeculativeDstOpaqueTypes.clear();
}
bool TypeMapTy::areTypesIsomorphic(Type *DstTy, Type *SrcTy) {
if (DstTy->getTypeID() != SrcTy->getTypeID())
return false;
Type *&Entry = MappedTypes[SrcTy];
if (Entry)
return Entry == DstTy;
if (DstTy == SrcTy) {
Entry = DstTy;
return true;
}
if (StructType *SSTy = dyn_cast<StructType>(SrcTy)) {
if (SSTy->isOpaque()) {
Entry = DstTy;
SpeculativeTypes.push_back(SrcTy);
return true;
}
if (cast<StructType>(DstTy)->isOpaque()) {
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 (SrcTy->getNumContainedTypes() != DstTy->getNumContainedTypes())
return false;
if (isa<IntegerType>(DstTy))
return false; 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 (ArrayType *DATy = dyn_cast<ArrayType>(DstTy)) {
if (DATy->getNumElements() != cast<ArrayType>(SrcTy)->getNumElements())
return false;
} else if (VectorType *DVTy = dyn_cast<VectorType>(DstTy)) {
if (DVTy->getNumElements() != cast<VectorType>(SrcTy)->getNumElements())
return false;
}
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;
return true;
}
void TypeMapTy::linkDefinedTypeBodies() {
SmallVector<Type *, 16> Elements;
for (StructType *SrcSTy : SrcDefinitionsToResolve) {
StructType *DstSTy = cast<StructType>(MappedTypes[SrcSTy]);
assert(DstSTy->isOpaque());
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());
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) {
Type **Entry = &MappedTypes[Ty];
if (*Entry)
return *Entry;
bool IsUniqued = !isa<StructType>(Ty) || cast<StructType>(Ty)->isLiteral();
#ifndef NDEBUG
if (!IsUniqued) {
for (auto &Pair : MappedTypes) {
assert(!(Pair.first != Ty && Pair.second == Ty) &&
"mapping to a source type");
}
}
#endif
if (!IsUniqued && !Visited.insert(cast<StructType>(Ty)).second) {
StructType *DTy = StructType::create(Ty->getContext());
return *Entry = DTy;
}
SmallVector<Type *, 4> ElementTypes;
if (Ty->getNumContainedTypes() == 0 && IsUniqued)
return *Entry = Ty;
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);
}
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 (!AnyChange && IsUniqued)
return *Entry = Ty;
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:
return *Entry = VectorType::get(ElementTypes[0],
cast<VectorType>(Ty)->getNumElements());
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 (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; }
namespace {
class IRLinker;
class GlobalValueMaterializer final : public ValueMaterializer {
IRLinker &TheIRLinker;
public:
GlobalValueMaterializer(IRLinker &TheIRLinker) : TheIRLinker(TheIRLinker) {}
Value *materializeDeclFor(Value *V) override;
void materializeInitFor(GlobalValue *New, GlobalValue *Old) override;
};
class LocalValueMaterializer final : public ValueMaterializer {
IRLinker &TheIRLinker;
public:
LocalValueMaterializer(IRLinker &TheIRLinker) : TheIRLinker(TheIRLinker) {}
Value *materializeDeclFor(Value *V) override;
void materializeInitFor(GlobalValue *New, GlobalValue *Old) override;
};
typedef DenseMap<const Metadata *, TrackingMDRef> MDMapT;
class IRLinker {
Module &DstM;
std::unique_ptr<Module> SrcM;
std::function<void(GlobalValue &, IRMover::ValueAdder)> AddLazyFor;
TypeMapTy TypeMap;
GlobalValueMaterializer GValMaterializer;
LocalValueMaterializer LValMaterializer;
MDMapT &SharedMDs;
ValueToValueMapTy ValueMap;
ValueToValueMapTy AliasValueMap;
DenseSet<GlobalValue *> ValuesToLink;
std::vector<GlobalValue *> Worklist;
void maybeAdd(GlobalValue *GV) {
if (ValuesToLink.insert(GV).second)
Worklist.push_back(GV);
}
bool DoneLinkingBodies = false;
bool HasError = false;
ValueMapper Mapper;
unsigned AliasMCID;
GlobalValue *copyGlobalValueProto(const GlobalValue *SGV, bool ForDefinition);
bool emitError(const Twine &Message) {
SrcM->getContext().diagnose(LinkDiagnosticInfo(DS_Error, Message));
HasError = true;
return true;
}
void emitWarning(const Twine &Message) {
SrcM->getContext().diagnose(LinkDiagnosticInfo(DS_Warning, Message));
}
GlobalValue *getLinkedToGlobal(const GlobalValue *SrcGV) {
if (!SrcGV->hasName() || SrcGV->hasLocalLinkage())
return nullptr;
GlobalValue *DGV = DstM.getNamedValue(SrcGV->getName());
if (!DGV)
return nullptr;
if (DGV->hasLocalLinkage())
return nullptr;
return DGV;
}
void computeTypeMapping();
Constant *linkAppendingVarProto(GlobalVariable *DstGV,
const GlobalVariable *SrcGV);
bool shouldLink(GlobalValue *DGV, GlobalValue &SGV);
Constant *linkGlobalValueProto(GlobalValue *GV, bool ForAlias);
bool linkModuleFlagsMetadata();
void linkGlobalInit(GlobalVariable &Dst, GlobalVariable &Src);
bool linkFunctionBody(Function &Dst, Function &Src);
void linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src);
bool linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src);
GlobalVariable *copyGlobalVariableProto(const GlobalVariable *SGVar);
Function *copyFunctionProto(const Function *SF);
GlobalValue *copyGlobalAliasProto(const GlobalAlias *SGA);
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)
: DstM(DstM), SrcM(std::move(SrcM)), AddLazyFor(AddLazyFor), TypeMap(Set),
GValMaterializer(*this), LValMaterializer(*this), SharedMDs(SharedMDs),
Mapper(ValueMap, RF_MoveDistinctMDs | RF_IgnoreMissingLocals, &TypeMap,
&GValMaterializer),
AliasMCID(Mapper.registerAlternateMappingContext(AliasValueMap,
&LValMaterializer)) {
ValueMap.getMDMap() = std::move(SharedMDs);
for (GlobalValue *GV : ValuesToLink)
maybeAdd(GV);
}
~IRLinker() { SharedMDs = std::move(*ValueMap.getMDMap()); }
bool run();
Value *materializeDeclFor(Value *V, bool ForAlias);
void materializeInitFor(GlobalValue *New, GlobalValue *Old, bool ForAlias);
};
}
static void forceRenaming(GlobalValue *GV, StringRef Name) {
if (GV->hasLocalLinkage() || GV->getName() == Name)
return;
Module *M = GV->getParent();
if (GlobalValue *ConflictGV = M->getNamedValue(Name)) {
GV->takeName(ConflictGV);
ConflictGV->setName(Name); assert(ConflictGV->getName() != Name && "forceRenaming didn't work");
} else {
GV->setName(Name); }
}
Value *GlobalValueMaterializer::materializeDeclFor(Value *V) {
return TheIRLinker.materializeDeclFor(V, false);
}
void GlobalValueMaterializer::materializeInitFor(GlobalValue *New,
GlobalValue *Old) {
TheIRLinker.materializeInitFor(New, Old, false);
}
Value *LocalValueMaterializer::materializeDeclFor(Value *V) {
return TheIRLinker.materializeDeclFor(V, true);
}
void LocalValueMaterializer::materializeInitFor(GlobalValue *New,
GlobalValue *Old) {
TheIRLinker.materializeInitFor(New, Old, true);
}
Value *IRLinker::materializeDeclFor(Value *V, bool ForAlias) {
auto *SGV = dyn_cast<GlobalValue>(V);
if (!SGV)
return nullptr;
return linkGlobalValueProto(SGV, ForAlias);
}
void IRLinker::materializeInitFor(GlobalValue *New, GlobalValue *Old,
bool ForAlias) {
if (auto *F = dyn_cast<Function>(New)) {
if (!F->isDeclaration())
return;
} else if (auto *V = dyn_cast<GlobalVariable>(New)) {
if (V->hasInitializer() || V->hasAppendingLinkage())
return;
} else {
auto *A = cast<GlobalAlias>(New);
if (A->getAliasee())
return;
}
if (ForAlias && ValueMap.lookup(Old) == New)
return;
if (ForAlias || shouldLink(New, *Old))
linkGlobalValueBody(*New, *Old);
}
GlobalVariable *IRLinker::copyGlobalVariableProto(const GlobalVariable *SGVar) {
GlobalVariable *NewDGV =
new GlobalVariable(DstM, TypeMap.get(SGVar->getValueType()),
SGVar->isConstant(), GlobalValue::ExternalLinkage,
nullptr, SGVar->getName(),
nullptr, SGVar->getThreadLocalMode(),
SGVar->getType()->getAddressSpace());
NewDGV->setAlignment(SGVar->getAlignment());
return NewDGV;
}
Function *IRLinker::copyFunctionProto(const Function *SF) {
return Function::Create(TypeMap.get(SF->getFunctionType()),
GlobalValue::ExternalLinkage, SF->getName(), &DstM);
}
GlobalValue *IRLinker::copyGlobalAliasProto(const GlobalAlias *SGA) {
auto *Ty = TypeMap.get(SGA->getValueType());
return GlobalAlias::create(Ty, SGA->getType()->getPointerAddressSpace(),
GlobalValue::ExternalLinkage, SGA->getName(),
&DstM);
}
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 = copyGlobalAliasProto(cast<GlobalAlias>(SGV));
else
NewGV = new GlobalVariable(
DstM, TypeMap.get(SGV->getValueType()),
false, GlobalValue::ExternalLinkage,
nullptr, SGV->getName(),
nullptr, SGV->getThreadLocalMode(),
SGV->getType()->getAddressSpace());
}
if (ForDefinition)
NewGV->setLinkage(SGV->getLinkage());
else if (SGV->hasExternalWeakLinkage())
NewGV->setLinkage(GlobalValue::ExternalWeakLinkage);
NewGV->copyAttributesFrom(SGV);
if (auto *NewF = dyn_cast<Function>(NewGV)) {
NewF->setPersonalityFn(nullptr);
NewF->setPrefixData(nullptr);
NewF->setPrologueData(nullptr);
}
return NewGV;
}
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;
}
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))
TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
for (GlobalValue &SGV : SrcM->aliases())
if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
std::vector<StructType *> Types = SrcM->getIdentifiedStructTypes();
for (StructType *ST : Types) {
if (!ST->hasName())
continue;
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;
StructType *DST = DstM.getTypeByName(ST->getName().substr(0, DotPos));
if (!DST)
continue;
if (TypeMap.DstStructTypesSet.hasType(DST))
TypeMap.addTypeMapping(DST, ST);
}
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));
}
Constant *IRLinker::linkAppendingVarProto(GlobalVariable *DstGV,
const GlobalVariable *SrcGV) {
Type *EltTy = cast<ArrayType>(TypeMap.get(SrcGV->getValueType()))
->getElementType();
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) {
ArrayType *DstTy = cast<ArrayType>(DstGV->getValueType());
DstNumElements = DstTy->getNumElements();
if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage()) {
emitError(
"Linking globals named '" + SrcGV->getName() +
"': can only link appending global with another appending global!");
return nullptr;
}
if (EltTy != DstTy->getElementType()) {
emitError("Appending variables with different element types!");
return nullptr;
}
if (DstGV->isConstant() != SrcGV->isConstant()) {
emitError("Appending variables linked with different const'ness!");
return nullptr;
}
if (DstGV->getAlignment() != SrcGV->getAlignment()) {
emitError(
"Appending variables with different alignment need to be linked!");
return nullptr;
}
if (DstGV->getVisibility() != SrcGV->getVisibility()) {
emitError(
"Appending variables with different visibility need to be linked!");
return nullptr;
}
if (DstGV->hasUnnamedAddr() != SrcGV->hasUnnamedAddr()) {
emitError(
"Appending variables with different unnamed_addr need to be linked!");
return nullptr;
}
if (StringRef(DstGV->getSection()) != SrcGV->getSection()) {
emitError(
"Appending variables with different section name need to be linked!");
return nullptr;
}
}
SmallVector<Constant *, 16> SrcElements;
getArrayElements(SrcGV->getInitializer(), SrcElements);
if (IsNewStructor)
SrcElements.erase(
std::remove_if(SrcElements.begin(), SrcElements.end(),
[this](Constant *E) {
auto *Key = dyn_cast<GlobalValue>(
E->getAggregateElement(2)->stripPointerCasts());
if (!Key)
return false;
GlobalValue *DGV = getLinkedToGlobal(Key);
return !shouldLink(DGV, *Key);
}),
SrcElements.end());
uint64_t NewSize = DstNumElements + SrcElements.size();
ArrayType *NewType = ArrayType::get(EltTy, NewSize);
GlobalVariable *NG = new GlobalVariable(
DstM, NewType, SrcGV->isConstant(), SrcGV->getLinkage(),
nullptr, "", DstGV, SrcGV->getThreadLocalMode(),
SrcGV->getType()->getAddressSpace());
NG->copyAttributesFrom(SrcGV);
forceRenaming(NG, SrcGV->getName());
Constant *Ret = ConstantExpr::getBitCast(NG, TypeMap.get(SrcGV->getType()));
Mapper.scheduleMapAppendingVariable(*NG,
DstGV ? DstGV->getInitializer() : nullptr,
IsOldStructor, SrcElements);
if (DstGV) {
DstGV->replaceAllUsesWith(ConstantExpr::getBitCast(NG, DstGV->getType()));
DstGV->eraseFromParent();
}
return Ret;
}
bool IRLinker::shouldLink(GlobalValue *DGV, GlobalValue &SGV) {
if (ValuesToLink.count(&SGV))
return true;
if (SGV.hasLocalLinkage())
return true;
if (DGV && !DGV->isDeclarationForLinker())
return false;
if (SGV.hasAvailableExternallyLinkage())
return true;
if (SGV.isDeclaration())
return false;
if (DoneLinkingBodies)
return false;
bool LazilyAdded = false;
AddLazyFor(SGV, [this, &LazilyAdded](GlobalValue &GV) {
maybeAdd(&GV);
LazilyAdded = true;
});
return LazilyAdded;
}
Constant *IRLinker::linkGlobalValueProto(GlobalValue *SGV, bool ForAlias) {
GlobalValue *DGV = getLinkedToGlobal(SGV);
bool ShouldLink = shouldLink(DGV, *SGV);
if (ShouldLink) {
auto I = ValueMap.find(SGV);
if (I != ValueMap.end())
return cast<Constant>(I->second);
I = AliasValueMap.find(SGV);
if (I != AliasValueMap.end())
return cast<Constant>(I->second);
}
if (!ShouldLink && ForAlias)
DGV = nullptr;
assert(!DGV || SGV->hasAppendingLinkage() == DGV->hasAppendingLinkage());
if (SGV->hasAppendingLinkage())
return linkAppendingVarProto(cast_or_null<GlobalVariable>(DGV),
cast<GlobalVariable>(SGV));
GlobalValue *NewGV;
if (DGV && !ShouldLink) {
NewGV = DGV;
} else {
if (DoneLinkingBodies)
return nullptr;
NewGV = copyGlobalValueProto(SGV, ShouldLink);
if (ShouldLink || !ForAlias)
forceRenaming(NewGV, SGV->getName());
}
if (ShouldLink || ForAlias) {
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 && ForAlias)
NewGV->setLinkage(GlobalValue::InternalLinkage);
Constant *C = NewGV;
if (DGV)
C = ConstantExpr::getBitCast(NewGV, TypeMap.get(SGV->getType()));
if (DGV && NewGV != DGV) {
DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewGV, DGV->getType()));
DGV->eraseFromParent();
}
return C;
}
void IRLinker::linkGlobalInit(GlobalVariable &Dst, GlobalVariable &Src) {
Mapper.scheduleMapGlobalInitializer(Dst, *Src.getInitializer());
}
bool IRLinker::linkFunctionBody(Function &Dst, Function &Src) {
assert(Dst.isDeclaration() && !Src.isDeclaration());
if (std::error_code EC = Src.materialize())
return emitError(EC.message());
if (Src.hasPrefixData())
Dst.setPrefixData(Src.getPrefixData());
if (Src.hasPrologueData())
Dst.setPrologueData(Src.getPrologueData());
if (Src.hasPersonalityFn())
Dst.setPersonalityFn(Src.getPersonalityFn());
SmallVector<std::pair<unsigned, MDNode *>, 8> MDs;
Src.getAllMetadata(MDs);
for (const auto &I : MDs)
Dst.setMetadata(I.first, I.second);
Dst.stealArgumentListFrom(Src);
Dst.getBasicBlockList().splice(Dst.end(), Src.getBasicBlockList());
Mapper.scheduleRemapFunction(Dst);
return false;
}
void IRLinker::linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src) {
Mapper.scheduleMapGlobalAliasee(Dst, *Src.getAliasee(), AliasMCID);
}
bool 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)) {
linkGlobalInit(cast<GlobalVariable>(Dst), *GVar);
return false;
}
linkAliasBody(cast<GlobalAlias>(Dst), cast<GlobalAlias>(Src));
return false;
}
void IRLinker::linkNamedMDNodes() {
const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
for (const NamedMDNode &NMD : SrcM->named_metadata()) {
if (&NMD == SrcModFlags)
continue;
NamedMDNode *DestNMD = DstM.getOrInsertNamedMetadata(NMD.getName());
for (const MDNode *Op : NMD.operands())
DestNMD->addOperand(Mapper.mapMDNode(*Op));
}
}
bool IRLinker::linkModuleFlagsMetadata() {
const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
if (!SrcModFlags)
return false;
NamedMDNode *DstModFlags = DstM.getOrInsertModuleFlagsMetadata();
if (DstModFlags->getNumOperands() == 0) {
for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
DstModFlags->addOperand(SrcModFlags->getOperand(I));
return false;
}
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);
}
}
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 (SrcBehaviorValue == Module::Require) {
if (Requirements.insert(cast<MDNode>(SrcOp->getOperand(2)))) {
DstModFlags->addOperand(SrcOp);
}
continue;
}
if (!DstOp) {
Flags[ID] = std::make_pair(SrcOp, DstModFlags->getNumOperands());
DstModFlags->addOperand(SrcOp);
continue;
}
ConstantInt *DstBehavior =
mdconst::extract<ConstantInt>(DstOp->getOperand(0));
unsigned DstBehaviorValue = DstBehavior->getZExtValue();
if (DstBehaviorValue == Module::Override) {
if (SrcBehaviorValue == Module::Override &&
SrcOp->getOperand(2) != DstOp->getOperand(2)) {
emitError("linking module flags '" + ID->getString() +
"': IDs have conflicting override values");
}
continue;
} else if (SrcBehaviorValue == Module::Override) {
DstModFlags->setOperand(DstIndex, SrcOp);
Flags[ID].first = SrcOp;
continue;
}
if (SrcBehaviorValue != DstBehaviorValue) {
emitError("linking module flags '" + ID->getString() +
"': IDs have conflicting behaviors");
continue;
}
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;
};
switch (SrcBehaviorValue) {
case Module::Require:
case Module::Override:
llvm_unreachable("not possible");
case Module::Error: {
if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
emitError("linking module flags '" + ID->getString() +
"': IDs have conflicting values");
}
continue;
}
case Module::Warning: {
if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
emitWarning("linking module flags '" + ID->getString() +
"': IDs have conflicting values");
}
continue;
}
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;
}
}
}
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) {
emitError("linking module flags '" + Flag->getString() +
"': does not have the required value");
continue;
}
}
return HasError;
}
static bool triplesMatch(const Triple &T0, const Triple &T1) {
if (T0.getVendor() == Triple::Apple)
return T0.getArch() == T1.getArch() && T0.getSubArch() == T1.getSubArch() &&
T0.getVendor() == T1.getVendor() && T0.getOS() == T1.getOS();
return T0 == T1;
}
static std::string mergeTriples(const Triple &SrcTriple,
const Triple &DstTriple) {
if (SrcTriple.getVendor() == Triple::Apple)
if (DstTriple.isOSVersionLT(SrcTriple))
return SrcTriple.str();
return DstTriple.str();
}
bool IRLinker::run() {
if (SrcM->getMaterializer() && SrcM->getMaterializer()->materializeMetadata())
return true;
if (DstM.getDataLayout().isDefault())
DstM.setDataLayout(SrcM->getDataLayout());
if (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 (DstM.getTargetTriple().empty() && !SrcM->getTargetTriple().empty())
DstM.setTargetTriple(SrcM->getTargetTriple());
Triple SrcTriple(SrcM->getTargetTriple()), DstTriple(DstM.getTargetTriple());
if (!SrcM->getTargetTriple().empty() && !triplesMatch(SrcTriple, DstTriple))
emitWarning("Linking two modules of different target triples: " +
SrcM->getModuleIdentifier() + "' is '" +
SrcM->getTargetTriple() + "' whereas '" +
DstM.getModuleIdentifier() + "' is '" + DstM.getTargetTriple() +
"'\n");
DstM.setTargetTriple(mergeTriples(SrcTriple, DstTriple));
if (!SrcM->getModuleInlineAsm().empty()) {
if (DstM.getModuleInlineAsm().empty())
DstM.setModuleInlineAsm(SrcM->getModuleInlineAsm());
else
DstM.setModuleInlineAsm(DstM.getModuleInlineAsm() + "\n" +
SrcM->getModuleInlineAsm());
}
computeTypeMapping();
std::reverse(Worklist.begin(), Worklist.end());
while (!Worklist.empty()) {
GlobalValue *GV = Worklist.back();
Worklist.pop_back();
if (ValueMap.find(GV) != ValueMap.end() ||
AliasValueMap.find(GV) != AliasValueMap.end())
continue;
assert(!GV->isDeclaration());
Mapper.mapValue(*GV);
if (HasError)
return true;
}
DoneLinkingBodies = true;
Mapper.addFlags(RF_NullMapMissingGlobalValues);
linkNamedMDNodes();
if (linkModuleFlagsMetadata())
return true;
return false;
}
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 {
if (IsPacked != That.IsPacked)
return false;
if (ETypes != That.ETypes)
return false;
return true;
}
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())
return LHS == getEmptyKey();
if (RHS == getTombstoneKey())
return LHS == getTombstoneKey();
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);
if (I == NonOpaqueStructTypes.end())
return nullptr;
return *I;
}
bool IRMover::IdentifiedStructTypeSet::hasType(StructType *Ty) {
if (Ty->isOpaque())
return OpaqueStructTypes.count(Ty);
auto I = NonOpaqueStructTypes.find(Ty);
if (I == NonOpaqueStructTypes.end())
return false;
return *I == Ty;
}
IRMover::IRMover(Module &M) : Composite(M) {
TypeFinder StructTypes;
StructTypes.run(M, true);
for (StructType *Ty : StructTypes) {
if (Ty->isOpaque())
IdentifiedStructTypes.addOpaque(Ty);
else
IdentifiedStructTypes.addNonOpaque(Ty);
}
for (auto *MD : StructTypes.getVisitedMetadata()) {
SharedMDs[MD].reset(const_cast<MDNode *>(MD));
}
}
bool IRMover::move(
std::unique_ptr<Module> Src, ArrayRef<GlobalValue *> ValuesToLink,
std::function<void(GlobalValue &, ValueAdder Add)> AddLazyFor) {
IRLinker TheIRLinker(Composite, SharedMDs, IdentifiedStructTypes,
std::move(Src), ValuesToLink, AddLazyFor);
bool RetCode = TheIRLinker.run();
Composite.dropTriviallyDeadConstantArrays();
return RetCode;
}