bool run();
private:
+ bool shouldLinkFromSource(const GlobalValue &Dest, const GlobalValue &Src);
+
/// emitError - Helper method for setting a message and returning an error
/// code.
bool emitError(const Twine &Message) {
SF->getLinkage(), SF->getName(), DstM);
copyGVAttributes(DF, SF);
+ if (Comdat *SC = SF->getComdat()) {
+ Comdat *DC = DstM->getOrInsertComdat(SC->getName());
+ DF->setComdat(DC);
+ }
+
LazilyLinkFunctions.push_back(SF);
return DF;
}
LinkFromSrc);
}
-/// getLinkageResult - This analyzes the two global values and determines what
-/// the result will look like in the destination module. In particular, it
-/// computes the resultant linkage type and visibility, computes whether the
-/// global in the source should be copied over to the destination (replacing
-/// the existing one), and computes whether this linkage is an error or not.
+// FIXME: Duplicated from the gold plugin. This should be refactored somewhere.
+static bool isDeclaration(const GlobalValue &V) {
+ if (V.hasAvailableExternallyLinkage())
+ return true;
+
+ if (V.isMaterializable())
+ return false;
+
+ return V.isDeclaration();
+}
+
+bool ModuleLinker::shouldLinkFromSource(const GlobalValue &Dest,
+ const GlobalValue &Src) {
+ bool SrcIsDeclaration = isDeclaration(Src);
+ bool DestIsDeclaration = isDeclaration(Dest);
+
+ // FIXME: Make datalayout mandatory and just use getDataLayout().
+ DataLayout DL(Dest.getParent());
+
+ 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.hasDLLImportStorageClass())
+ // If one of GVs is marked as DLLImport, result should be dllimport'ed.
+ return DestIsDeclaration;
+ // If the Dest is weak, use the source linkage.
+ return Dest.hasExternalWeakLinkage();
+ }
+
+ if (DestIsDeclaration)
+ // If Dest is external but Src is not:
+ return true;
+
+ if (Src.hasCommonLinkage()) {
+ if (Dest.hasLinkOnceLinkage() || Dest.hasWeakLinkage())
+ return true;
+
+ if (!Dest.hasCommonLinkage())
+ return false;
+
+ uint64_t DestSize = DL.getTypeAllocSize(Dest.getType()->getElementType());
+ uint64_t SrcSize = DL.getTypeAllocSize(Src.getType()->getElementType());
+ return SrcSize > DestSize;
+ }
+
+ if (Src.isWeakForLinker()) {
+ assert(!Dest.hasExternalWeakLinkage());
+ assert(!Dest.hasAvailableExternallyLinkage());
+
+ if (Dest.hasLinkOnceLinkage() && Src.hasWeakLinkage())
+ return true;
+
+ return false;
+ }
+
+ if (Dest.isWeakForLinker()) {
+ assert(Src.hasExternalLinkage());
+ return true;
+ }
+
+ assert(!Src.hasExternalWeakLinkage());
+ assert(!Dest.hasExternalWeakLinkage());
+ assert(Dest.hasExternalLinkage() && Src.hasExternalLinkage() &&
+ "Unexpected linkage type!");
+ return emitError("Linking globals named '" + Src.getName() +
+ "': symbol multiply defined!");
+}
+
+/// This analyzes the two global values and determines what the result will look
+/// like in the destination module. In particular, it computes the resultant
+/// linkage type and visibility, computes whether the global in the source
+/// should be copied over to the destination (replacing the existing one), and
+/// computes whether this linkage is an error or not.
bool ModuleLinker::getLinkageResult(GlobalValue *Dest, const GlobalValue *Src,
GlobalValue::LinkageTypes <,
GlobalValue::VisibilityTypes &Vis,
assert(!Src->hasLocalLinkage() &&
"If Src has internal linkage, Dest shouldn't be set!");
- bool SrcIsDeclaration = Src->isDeclaration() && !Src->isMaterializable();
- bool DestIsDeclaration = Dest->isDeclaration();
+ assert(ErrorMsg.empty());
+ LinkFromSrc = shouldLinkFromSource(*Dest, *Src);
+ if (!ErrorMsg.empty())
+ return true;
- 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->hasDLLImportStorageClass()) {
- // If one of GVs is marked as DLLImport, result should be dllimport'ed.
- if (DestIsDeclaration) {
- LinkFromSrc = true;
- LT = Src->getLinkage();
- }
- } else if (Dest->hasExternalWeakLinkage()) {
- // If the Dest is weak, use the source linkage.
- LinkFromSrc = true;
- LT = Src->getLinkage();
- } else {
- LinkFromSrc = false;
- LT = Dest->getLinkage();
- }
- } else if (DestIsDeclaration && !Dest->hasDLLImportStorageClass()) {
- // If Dest is external but Src is not:
- LinkFromSrc = true;
+ if (LinkFromSrc)
LT = Src->getLinkage();
- } else if (Src->isWeakForLinker()) {
- // At this point we know that Dest has LinkOnce, External*, Weak, Common,
- // or DLL* linkage.
- if (Dest->hasExternalWeakLinkage() ||
- Dest->hasAvailableExternallyLinkage() ||
- (Dest->hasLinkOnceLinkage() &&
- (Src->hasWeakLinkage() || Src->hasCommonLinkage()))) {
- LinkFromSrc = true;
- LT = Src->getLinkage();
- } else {
- LinkFromSrc = false;
- LT = Dest->getLinkage();
- }
- } else if (Dest->isWeakForLinker()) {
- // At this point we know that Src has External* or DLL* linkage.
- if (Src->hasExternalWeakLinkage()) {
- LinkFromSrc = false;
- LT = Dest->getLinkage();
- } else {
- LinkFromSrc = true;
- LT = GlobalValue::ExternalLinkage;
- }
- } else {
- assert((Dest->hasExternalLinkage() || Dest->hasExternalWeakLinkage()) &&
- (Src->hasExternalLinkage() || Src->hasExternalWeakLinkage()) &&
- "Unexpected linkage type!");
- return emitError("Linking globals named '" + Src->getName() +
- "': symbol multiply defined!");
- }
+ else
+ LT = Dest->getLinkage();
// Compute the visibility. We follow the rules in the System V Application
// Binary Interface.
GlobalValue *DGV = getLinkedToGlobal(SGV);
llvm::Optional<GlobalValue::VisibilityTypes> NewVisibility;
bool HasUnnamedAddr = SGV->hasUnnamedAddr();
+ unsigned Alignment = SGV->getAlignment();
bool LinkFromSrc = false;
Comdat *DC = nullptr;
return true;
NewVisibility = NV;
HasUnnamedAddr = HasUnnamedAddr && DGV->hasUnnamedAddr();
+ if (DGV->hasCommonLinkage() && SGV->hasCommonLinkage())
+ Alignment = std::max(Alignment, DGV->getAlignment());
+ else if (!LinkFromSrc)
+ Alignment = DGV->getAlignment();
// 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 (GlobalVariable *DGVar = dyn_cast<GlobalVariable>(DGV)) {
+ DGVar->setAlignment(Alignment);
+
if (DGVar->isDeclaration() && SGV->isConstant() &&
!DGVar->isConstant())
DGVar->setConstant(true);
+ }
// Set calculated linkage, visibility and unnamed_addr.
DGV->setLinkage(NewLinkage);
SGV->getType()->getAddressSpace());
// Propagate alignment, visibility and section info.
copyGVAttributes(NewDGV, SGV);
+ NewDGV->setAlignment(Alignment);
if (NewVisibility)
NewDGV->setVisibility(*NewVisibility);
NewDGV->setUnnamedAddr(HasUnnamedAddr);
void ModuleLinker::linkAppendingVarInit(const AppendingVarInfo &AVI) {
// Merge the initializer.
- SmallVector<Constant*, 16> Elements;
- getArrayElements(AVI.DstInit, Elements);
+ SmallVector<Constant *, 16> DstElements;
+ getArrayElements(AVI.DstInit, DstElements);
- Constant *SrcInit = MapValue(AVI.SrcInit, ValueMap, RF_None, &TypeMap, &ValMaterializer);
- getArrayElements(SrcInit, Elements);
+ SmallVector<Constant *, 16> SrcElements;
+ getArrayElements(AVI.SrcInit, SrcElements);
ArrayType *NewType = cast<ArrayType>(AVI.NewGV->getType()->getElementType());
- AVI.NewGV->setInitializer(ConstantArray::get(NewType, Elements));
+
+ StringRef Name = AVI.NewGV->getName();
+ bool IsNewStructor =
+ (Name == "llvm.global_ctors" || Name == "llvm.global_dtors") &&
+ cast<StructType>(NewType->getElementType())->getNumElements() == 3;
+
+ for (auto *V : SrcElements) {
+ if (IsNewStructor) {
+ Constant *Key = V->getAggregateElement(2);
+ if (DoNotLinkFromSource.count(Key))
+ continue;
+ }
+ DstElements.push_back(
+ MapValue(V, ValueMap, RF_None, &TypeMap, &ValMaterializer));
+ }
+ if (IsNewStructor) {
+ NewType = ArrayType::get(NewType->getElementType(), DstElements.size());
+ AVI.NewGV->mutateType(PointerType::get(NewType, 0));
+ }
+
+ AVI.NewGV->setInitializer(ConstantArray::get(NewType, DstElements));
}
/// linkGlobalInits - Update the initializers in the Dest module now that all
projects / oota-llvm.git / blobdiff