//
//===----------------------------------------------------------------------===//
-#include "llvm/Linker.h"
+#include "llvm/Linker/Linker.h"
#include "llvm-c/Linker.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/IR/Constants.h"
+#include "llvm/IR/DiagnosticInfo.h"
+#include "llvm/IR/DiagnosticPrinter.h"
+#include "llvm/IR/LLVMContext.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.
//===----------------------------------------------------------------------===//
namespace {
- typedef SmallPtrSet<StructType*, 32> TypeSet;
+typedef SmallPtrSet<StructType *, 32> TypeSet;
class TypeMapTy : public ValueMapTypeRemapper {
- /// MappedTypes - This is a mapping from a source type to a destination type
- /// to use.
+ /// This is a mapping from a source type to a destination type to use.
DenseMap<Type*, Type*> MappedTypes;
- /// SpeculativeTypes - 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.
+ /// 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;
-
- /// SrcDefinitionsToResolve - This is a list of non-opaque structs in the
- /// source module that are mapped to an opaque struct in the destination
- /// module.
+
+ /// 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.
+
+ /// 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(TypeSet &Set) : DstStructTypesSet(Set) {}
TypeSet &DstStructTypesSet;
- /// addTypeMapping - Indicate that the specified type in the destination
- /// module is conceptually equivalent to the specified type in the source
- /// module.
+ /// 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);
/// 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
+
+ /// Return the mapped type to use for the specified input type from the
/// source module.
Type *get(Type *SrcTy);
FunctionType *get(FunctionType *T) {return cast<FunctionType>(get((Type*)T));}
- /// dump - Dump out the type map for debugging purposes.
+ /// Dump out the type map for debugging purposes.
void dump() const {
for (DenseMap<Type*, Type*>::const_iterator
I = MappedTypes.begin(), E = MappedTypes.end(); I != E; ++I) {
dbgs() << "TypeMap: ";
- I->first->dump();
+ I->first->print(dbgs());
dbgs() << " => ";
- I->second->dump();
+ I->second->print(dbgs());
dbgs() << '\n';
}
}
private:
Type *getImpl(Type *T);
- /// remapType - Implement the ValueMapTypeRemapper interface.
- Type *remapType(Type *SrcTy) {
+ /// Implement the ValueMapTypeRemapper interface.
+ Type *remapType(Type *SrcTy) override {
return get(SrcTy);
}
-
+
bool areTypesIsomorphic(Type *DstTy, Type *SrcTy);
};
}
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)) {
SpeculativeTypes.clear();
}
-/// areTypesIsomorphic - Recursively walk this pair of types, returning true
-/// if they are isomorphic, false if they are not.
+/// 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;
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.
// 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)))
+ if (!DstResolvedOpaqueTypes.insert(cast<StructType>(DstTy)).second)
return false;
SrcDefinitionsToResolve.push_back(SSTy);
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;
if (!areTypesIsomorphic(DstTy->getContainedType(i),
SrcTy->getContainedType(i)))
return false;
-
+
// If everything seems to have lined up, then everything is great.
return true;
}
-/// linkDefinedTypeBodies - Produce a body for an opaque type in the dest
-/// module from a type definition in the source module.
+/// Produce a body for an opaque type in the dest module from a type definition
+/// in the source module.
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("");
TmpName.clear();
}
}
-
+
DstResolvedOpaqueTypes.clear();
}
-/// get - Return the mapped type to use for the specified input type from the
-/// 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();
return Result;
}
-/// getImpl - This is the recursive version of get().
+/// This is the recursive version of get().
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()) {
// 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;
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:
// 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
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);
namespace {
class ModuleLinker;
- /// ValueMaterializerTy - 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.
+ /// 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 ValueMaterializerTy : public ValueMaterializer {
TypeMapTy &TypeMap;
Module *DstM;
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.
+ namespace {
+ class LinkDiagnosticInfo : public DiagnosticInfo {
+ const Twine &Msg;
+
+ public:
+ LinkDiagnosticInfo(DiagnosticSeverity Severity, const Twine &Msg);
+ void print(DiagnosticPrinter &DP) const override;
+ };
+ LinkDiagnosticInfo::LinkDiagnosticInfo(DiagnosticSeverity Severity,
+ const Twine &Msg)
+ : DiagnosticInfo(DK_Linker, Severity), Msg(Msg) {}
+ void LinkDiagnosticInfo::print(DiagnosticPrinter &DP) const { DP << Msg; }
+ }
+
+ /// 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
- /// 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.
+ /// 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;
-
+
struct AppendingVarInfo {
- GlobalVariable *NewGV; // New aggregate global in dest module.
- Constant *DstInit; // Old initializer from dest module.
- Constant *SrcInit; // Old initializer from src module.
+ GlobalVariable *NewGV; // New aggregate global in dest module.
+ const Constant *DstInit; // Old initializer from dest module.
+ const 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;
-
+
+ Linker::DiagnosticHandlerFunction DiagnosticHandler;
+
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,
+ Linker::DiagnosticHandlerFunction DiagnosticHandler)
+ : DstM(dstM), SrcM(srcM), TypeMap(Set),
+ ValMaterializer(TypeMap, DstM, LazilyLinkFunctions),
+ DiagnosticHandler(DiagnosticHandler) {}
+
bool run();
-
+
private:
- /// emitError - Helper method for setting a message and returning an error
- /// code.
+ bool shouldLinkFromSource(bool &LinkFromSrc, const GlobalValue &Dest,
+ const GlobalValue &Src);
+
+ /// Helper method for setting a message and returning an error code.
bool emitError(const Twine &Message) {
- ErrorMsg = Message.str();
+ DiagnosticHandler(LinkDiagnosticInfo(DS_Error, Message));
return true;
}
-
- /// 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,
- GlobalValue::LinkageTypes <,
- GlobalValue::VisibilityTypes &Vis,
- bool &LinkFromSrc);
-
- /// getLinkedToGlobal - Given a global in the source module, return the
- /// global in the destination module that is being linked to, if any.
- GlobalValue *getLinkedToGlobal(GlobalValue *SrcGV) {
+
+ void emitWarning(const Twine &Message) {
+ DiagnosticHandler(LinkDiagnosticInfo(DS_Warning, Message));
+ }
+
+ 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);
+
+ /// 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 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);
+
+ void upgradeMismatchedGlobalArray(StringRef Name);
+ void upgradeMismatchedGlobals();
+
+ bool linkAppendingVarProto(GlobalVariable *DstGV,
+ const GlobalVariable *SrcGV);
+
+ bool linkGlobalValueProto(GlobalValue *GV);
+ GlobalValue *linkGlobalVariableProto(const GlobalVariable *SGVar,
+ GlobalValue *DGV, bool LinkFromSrc);
+ GlobalValue *linkFunctionProto(const Function *SF, GlobalValue *DGV,
+ bool LinkFromSrc);
+ GlobalValue *linkGlobalAliasProto(const GlobalAlias *SGA, GlobalValue *DGV,
+ bool LinkFromSrc);
+
bool linkModuleFlagsMetadata();
-
+
void linkAppendingVarInit(const AppendingVarInfo &AVI);
void linkGlobalInits();
void linkFunctionBody(Function *Dst, Function *Src);
};
}
-/// forceRenaming - 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.
+/// 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.
}
}
-/// copyGVAttributes - copy additional attributes (those not needed to construct
-/// a GlobalValue) from the SrcGV to the DestGV.
+/// copy additional attributes (those not needed to construct 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());
}
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);
copyGVAttributes(DF, SF);
+ if (Comdat *SC = SF->getComdat()) {
+ Comdat *DC = DstM->getOrInsertComdat(SC->getName());
+ DF->setComdat(DC);
+ }
+
LazilyLinkFunctions.push_back(SF);
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) {
+ Comdat::SelectionKind SSK = SrcC->getSelectionKind();
+ StringRef ComdatName = SrcC->getName();
+ Module::ComdatSymTabType &ComdatSymTab = DstM->getComdatSymbolTable();
+ Module::ComdatSymTabType::iterator DstCI = ComdatSymTab.find(ComdatName);
+
+ if (DstCI == ComdatSymTab.end()) {
+ // Use the comdat if it is only available in one of the modules.
+ LinkFromSrc = true;
+ Result = SSK;
+ return false;
+ }
+
+ const Comdat *DstC = &DstCI->second;
+ Comdat::SelectionKind DSK = DstC->getSelectionKind();
+ return computeResultingSelectionKind(ComdatName, SSK, DSK, Result,
+ LinkFromSrc);
+}
+
+bool ModuleLinker::shouldLinkFromSource(bool &LinkFromSrc,
+ const GlobalValue &Dest,
+ const GlobalValue &Src) {
+ // We always have to add Src if it has appending linkage.
+ if (Src.hasAppendingLinkage()) {
+ LinkFromSrc = true;
+ return false;
+ }
+
+ bool SrcIsDeclaration = Src.isDeclarationForLinker();
+ bool DestIsDeclaration = Dest.isDeclarationForLinker();
-/// 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.
-bool ModuleLinker::getLinkageResult(GlobalValue *Dest, const GlobalValue *Src,
- GlobalValue::LinkageTypes <,
- GlobalValue::VisibilityTypes &Vis,
- bool &LinkFromSrc) {
- 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 (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();
+ if (Src.hasDLLImportStorageClass()) {
+ // If one of GVs is marked as DLLImport, result should be dllimport'ed.
+ LinkFromSrc = DestIsDeclaration;
+ return false;
}
- } else if (DestIsDeclaration && !Dest->hasDLLImportLinkage()) {
+ // If the Dest is weak, use the source linkage.
+ LinkFromSrc = Dest.hasExternalWeakLinkage();
+ return false;
+ }
+
+ if (DestIsDeclaration) {
// If Dest is external but Src is not:
LinkFromSrc = true;
- 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()))) {
+ return false;
+ }
+
+ if (Src.hasCommonLinkage()) {
+ if (Dest.hasLinkOnceLinkage() || Dest.hasWeakLinkage()) {
LinkFromSrc = true;
- LT = Src->getLinkage();
- } else {
- LinkFromSrc = false;
- LT = Dest->getLinkage();
+ return false;
}
- } else if (Dest->isWeakForLinker()) {
- // At this point we know that Src has External* or DLL* linkage.
- if (Src->hasExternalWeakLinkage()) {
+
+ if (!Dest.hasCommonLinkage()) {
LinkFromSrc = false;
- LT = Dest->getLinkage();
- } else {
+ return false;
+ }
+
+ // FIXME: Make datalayout mandatory and just use getDataLayout().
+ DataLayout DL(Dest.getParent());
+
+ uint64_t DestSize = DL.getTypeAllocSize(Dest.getType()->getElementType());
+ uint64_t SrcSize = DL.getTypeAllocSize(Src.getType()->getElementType());
+ LinkFromSrc = SrcSize > DestSize;
+ return false;
+ }
+
+ if (Src.isWeakForLinker()) {
+ assert(!Dest.hasExternalWeakLinkage());
+ assert(!Dest.hasAvailableExternallyLinkage());
+
+ if (Dest.hasLinkOnceLinkage() && Src.hasWeakLinkage()) {
LinkFromSrc = true;
- LT = GlobalValue::ExternalLinkage;
+ return false;
}
- } else {
- assert((Dest->hasExternalLinkage() || Dest->hasDLLImportLinkage() ||
- Dest->hasDLLExportLinkage() || Dest->hasExternalWeakLinkage()) &&
- (Src->hasExternalLinkage() || Src->hasDLLImportLinkage() ||
- Src->hasDLLExportLinkage() || Src->hasExternalWeakLinkage()) &&
- "Unexpected linkage type!");
- return emitError("Linking globals named '" + Src->getName() +
- "': symbol multiply defined!");
+
+ LinkFromSrc = false;
+ return false;
}
- // Compute the visibility. We follow the rules in the System V Application
- // Binary Interface.
- Vis = isLessConstraining(Src->getVisibility(), Dest->getVisibility()) ?
- Dest->getVisibility() : Src->getVisibility();
- return false;
+ if (Dest.isWeakForLinker()) {
+ assert(Src.hasExternalLinkage());
+ LinkFromSrc = true;
+ return false;
+ }
+
+ assert(!Src.hasExternalWeakLinkage());
+ assert(!Dest.hasExternalWeakLinkage());
+ assert(Dest.hasExternalLinkage() && Src.hasExternalLinkage() &&
+ "Unexpected linkage type!");
+ return emitError("Linking globals named '" + Src.getName() +
+ "': symbol multiply defined!");
}
-/// computeTypeMapping - 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.
+/// 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 ModuleLinker::computeTypeMapping() {
// Incorporate globals.
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))
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
}
// 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();
}
-/// linkAppendingVarProto - If there were any appending global variables, link
-/// them together now. Return true on error.
+static void upgradeGlobalArray(GlobalVariable *GV) {
+ ArrayType *ATy = cast<ArrayType>(GV->getType()->getElementType());
+ StructType *OldTy = cast<StructType>(ATy->getElementType());
+ assert(OldTy->getNumElements() == 2 && "Expected to upgrade from 2 elements");
+
+ // Get the upgraded 3 element type.
+ PointerType *VoidPtrTy = Type::getInt8Ty(GV->getContext())->getPointerTo();
+ Type *Tys[3] = {OldTy->getElementType(0), OldTy->getElementType(1),
+ VoidPtrTy};
+ StructType *NewTy = StructType::get(GV->getContext(), Tys, false);
+
+ // Build new constants with a null third field filled in.
+ Constant *OldInitC = GV->getInitializer();
+ ConstantArray *OldInit = dyn_cast<ConstantArray>(OldInitC);
+ if (!OldInit && !isa<ConstantAggregateZero>(OldInitC))
+ // Invalid initializer; give up.
+ return;
+ std::vector<Constant *> Initializers;
+ if (OldInit && OldInit->getNumOperands()) {
+ Value *Null = Constant::getNullValue(VoidPtrTy);
+ for (Use &U : OldInit->operands()) {
+ ConstantStruct *Init = cast<ConstantStruct>(U.get());
+ Initializers.push_back(ConstantStruct::get(
+ NewTy, Init->getOperand(0), Init->getOperand(1), Null, nullptr));
+ }
+ }
+ assert(Initializers.size() == ATy->getNumElements() &&
+ "Failed to copy all array elements");
+
+ // Replace the old GV with a new one.
+ ATy = ArrayType::get(NewTy, Initializers.size());
+ Constant *NewInit = ConstantArray::get(ATy, Initializers);
+ GlobalVariable *NewGV = new GlobalVariable(
+ *GV->getParent(), ATy, GV->isConstant(), GV->getLinkage(), NewInit, "",
+ GV, GV->getThreadLocalMode(), GV->getType()->getAddressSpace(),
+ GV->isExternallyInitialized());
+ NewGV->copyAttributesFrom(GV);
+ NewGV->takeName(GV);
+ assert(GV->use_empty() && "program cannot use initializer list");
+ GV->eraseFromParent();
+}
+
+void ModuleLinker::upgradeMismatchedGlobalArray(StringRef Name) {
+ // Look for the global arrays.
+ auto *DstGV = dyn_cast_or_null<GlobalVariable>(DstM->getNamedValue(Name));
+ if (!DstGV)
+ return;
+ auto *SrcGV = dyn_cast_or_null<GlobalVariable>(SrcM->getNamedValue(Name));
+ if (!SrcGV)
+ return;
+
+ // Check if the types already match.
+ auto *DstTy = cast<ArrayType>(DstGV->getType()->getElementType());
+ auto *SrcTy =
+ cast<ArrayType>(TypeMap.get(SrcGV->getType()->getElementType()));
+ if (DstTy == SrcTy)
+ return;
+
+ // Grab the element types. We can only upgrade an array of a two-field
+ // struct. Only bother if the other one has three-fields.
+ auto *DstEltTy = cast<StructType>(DstTy->getElementType());
+ auto *SrcEltTy = cast<StructType>(SrcTy->getElementType());
+ if (DstEltTy->getNumElements() == 2 && SrcEltTy->getNumElements() == 3) {
+ upgradeGlobalArray(DstGV);
+ return;
+ }
+ if (DstEltTy->getNumElements() == 3 && SrcEltTy->getNumElements() == 2)
+ upgradeGlobalArray(SrcGV);
+
+ // We can't upgrade any other differences.
+}
+
+void ModuleLinker::upgradeMismatchedGlobals() {
+ upgradeMismatchedGlobalArray("llvm.global_ctors");
+ upgradeMismatchedGlobalArray("llvm.global_dtors");
+}
+
+/// If there were any appending global variables, link them together now.
+/// Return true on error.
bool ModuleLinker::linkAppendingVarProto(GlobalVariable *DstGV,
- GlobalVariable *SrcGV) {
-
+ const 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!");
-
- if (DstGV->getSection() != SrcGV->getSection())
+
+ if (DstGV->hasUnnamedAddr() != SrcGV->hasUnnamedAddr())
+ return emitError(
+ "Appending variables with different unnamed_addr need to be linked!");
+
+ 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();
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;
}
-/// linkGlobalProto - Loop through the global variables in the src module and
-/// merge them into the dest module.
-bool ModuleLinker::linkGlobalProto(GlobalVariable *SGV) {
+bool ModuleLinker::linkGlobalValueProto(GlobalValue *SGV) {
GlobalValue *DGV = getLinkedToGlobal(SGV);
- llvm::Optional<GlobalValue::VisibilityTypes> NewVisibility;
+
+ // Handle the ultra special appending linkage case first.
+ if (DGV && DGV->hasAppendingLinkage())
+ return linkAppendingVarProto(cast<GlobalVariable>(DGV),
+ cast<GlobalVariable>(SGV));
+
+ bool LinkFromSrc = true;
+ Comdat *C = nullptr;
+ GlobalValue::VisibilityTypes Visibility = SGV->getVisibility();
bool HasUnnamedAddr = SGV->hasUnnamedAddr();
- 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))
+ if (const Comdat *SC = SGV->getComdat()) {
+ Comdat::SelectionKind SK;
+ std::tie(SK, LinkFromSrc) = ComdatsChosen[SC];
+ C = DstM->getOrInsertComdat(SC->getName());
+ C->setSelectionKind(SK);
+ } else if (DGV) {
+ if (shouldLinkFromSource(LinkFromSrc, *DGV, *SGV))
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 (!LinkFromSrc) {
+ // Track the source global so that we don't attempt to copy it over when
+ // processing global initializers.
+ DoNotLinkFromSource.insert(SGV);
+ if (DGV)
// 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
- // processing global initializers.
- DoNotLinkFromSource.insert(SGV);
-
- return false;
- }
+ ValueMap[SGV] =
+ ConstantExpr::getBitCast(DGV, TypeMap.get(SGV->getType()));
}
-
- // 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->getThreadLocalMode(),
- SGV->getType()->getAddressSpace());
- // Propagate alignment, visibility and section info.
- copyGVAttributes(NewDGV, SGV);
- if (NewVisibility)
- NewDGV->setVisibility(*NewVisibility);
- NewDGV->setUnnamedAddr(HasUnnamedAddr);
if (DGV) {
- DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewDGV, DGV->getType()));
- DGV->eraseFromParent();
+ Visibility = isLessConstraining(Visibility, DGV->getVisibility())
+ ? DGV->getVisibility()
+ : Visibility;
+ HasUnnamedAddr = HasUnnamedAddr && DGV->hasUnnamedAddr();
}
-
- // Make sure to remember this mapping.
- ValueMap[SGV] = NewDGV;
+
+ if (!LinkFromSrc && !DGV)
+ return false;
+
+ GlobalValue *NewGV;
+ if (auto *SGVar = dyn_cast<GlobalVariable>(SGV)) {
+ NewGV = linkGlobalVariableProto(SGVar, DGV, LinkFromSrc);
+ if (!NewGV)
+ return true;
+ } else if (auto *SF = dyn_cast<Function>(SGV)) {
+ NewGV = linkFunctionProto(SF, DGV, LinkFromSrc);
+ } else {
+ NewGV = linkGlobalAliasProto(cast<GlobalAlias>(SGV), DGV, LinkFromSrc);
+ }
+
+ if (NewGV) {
+ if (NewGV != DGV)
+ copyGVAttributes(NewGV, SGV);
+
+ NewGV->setUnnamedAddr(HasUnnamedAddr);
+ NewGV->setVisibility(Visibility);
+
+ if (auto *NewGO = dyn_cast<GlobalObject>(NewGV)) {
+ if (C)
+ NewGO->setComdat(C);
+ }
+
+ // Make sure to remember this mapping.
+ if (NewGV != DGV) {
+ if (DGV) {
+ DGV->replaceAllUsesWith(
+ ConstantExpr::getBitCast(NewGV, DGV->getType()));
+ DGV->eraseFromParent();
+ }
+ ValueMap[SGV] = NewGV;
+ }
+ }
+
return false;
}
-/// linkFunctionProto - Link the function in the source module into the
-/// destination module if needed, setting up mapping information.
-bool ModuleLinker::linkFunctionProto(Function *SF) {
- GlobalValue *DGV = getLinkedToGlobal(SF);
- llvm::Optional<GlobalValue::VisibilityTypes> NewVisibility;
- bool HasUnnamedAddr = SF->hasUnnamedAddr();
+/// Loop through the global variables in the src module and merge them into the
+/// dest module.
+GlobalValue *ModuleLinker::linkGlobalVariableProto(const GlobalVariable *SGVar,
+ GlobalValue *DGV,
+ bool LinkFromSrc) {
+ unsigned Alignment = 0;
+ bool ClearConstant = false;
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 (DGV->hasCommonLinkage() && SGVar->hasCommonLinkage())
+ Alignment = std::max(SGVar->getAlignment(), DGV->getAlignment());
- if (!LinkFromSrc) {
- // Set calculated linkage
- DGV->setLinkage(NewLinkage);
- DGV->setVisibility(*NewVisibility);
- DGV->setUnnamedAddr(HasUnnamedAddr);
+ auto *DGVar = dyn_cast<GlobalVariable>(DGV);
+ if (!SGVar->isConstant() || (DGVar && !DGVar->isConstant()))
+ ClearConstant = true;
+ }
- // 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
- // it.
- DoNotLinkFromSource.insert(SF);
-
- return false;
+ if (!LinkFromSrc) {
+ if (auto *NewGVar = dyn_cast<GlobalVariable>(DGV)) {
+ if (Alignment)
+ NewGVar->setAlignment(Alignment);
+ if (NewGVar->isDeclaration() && ClearConstant)
+ NewGVar->setConstant(false);
}
+ return DGV;
}
-
+
+ // 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->getType()->getElementType()),
+ SGVar->isConstant(), SGVar->getLinkage(), /*init*/ nullptr,
+ SGVar->getName(), /*insertbefore*/ nullptr, SGVar->getThreadLocalMode(),
+ SGVar->getType()->getAddressSpace());
+
+ if (Alignment)
+ NewDGV->setAlignment(Alignment);
+
+ return NewDGV;
+}
+
+/// Link the function in the source module into the destination module if
+/// needed, setting up mapping information.
+GlobalValue *ModuleLinker::linkFunctionProto(const Function *SF,
+ GlobalValue *DGV,
+ bool LinkFromSrc) {
+ if (!LinkFromSrc)
+ return DGV;
+
// 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() ||
SF->hasAvailableExternallyLinkage())) {
DoNotLinkFromSource.insert(SF);
- return false;
+ return nullptr;
}
// 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()),
- SF->getLinkage(), SF->getName(), DstM);
- copyGVAttributes(NewDF, SF);
- if (NewVisibility)
- NewDF->setVisibility(*NewVisibility);
- NewDF->setUnnamedAddr(HasUnnamedAddr);
-
- 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;
+ return Function::Create(TypeMap.get(SF->getFunctionType()), SF->getLinkage(),
+ SF->getName(), DstM);
}
-/// LinkAliasProto - Set up prototypes for any aliases that come over from the
-/// source module.
-bool ModuleLinker::linkAliasProto(GlobalAlias *SGA) {
- GlobalValue *DGV = getLinkedToGlobal(SGA);
- llvm::Optional<GlobalValue::VisibilityTypes> NewVisibility;
+/// Set up prototypes for any aliases that come over from the source module.
+GlobalValue *ModuleLinker::linkGlobalAliasProto(const GlobalAlias *SGA,
+ GlobalValue *DGV,
+ bool LinkFromSrc) {
+ if (!LinkFromSrc)
+ return DGV;
- 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 (!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 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);
- copyGVAttributes(NewDA, SGA);
- if (NewVisibility)
- NewDA->setVisibility(*NewVisibility);
-
- 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;
+ auto *PTy = cast<PointerType>(TypeMap.get(SGA->getType()));
+ return GlobalAlias::create(PTy->getElementType(), PTy->getAddressSpace(),
+ SGA->getLinkage(), SGA->getName(), DstM);
}
-static void getArrayElements(Constant *C, SmallVectorImpl<Constant*> &Dest) {
+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));
}
-
+
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);
-
+ SmallVector<Constant *, 16> DstElements;
+ getArrayElements(AVI.DstInit, DstElements);
+
+ 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
-/// globals that may be referenced are in Dest.
+/// Update the initializers in the Dest module now that all globals that may be
+/// referenced are in Dest.
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.
}
}
-/// linkFunctionBody - 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.
+/// 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.
void ModuleLinker::linkFunctionBody(Function *Dst, Function *Src) {
assert(Src && Dst && Dst->isDeclaration() && !Src->isDeclaration());
ValueMap[I] = DI;
}
- 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
- // functions and patch them up to point to the local versions.
- for (Function::iterator BB = Dst->begin(), BE = Dst->end(); BB != BE; ++BB)
- 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,
- &TypeMap, &ValMaterializer);
- }
-
+ // 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
+ // functions and patch them up to point to the local versions.
+ for (Function::iterator BB = Dst->begin(), BE = Dst->end(); BB != BE; ++BB)
+ for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ++I)
+ RemapInstruction(I, ValueMap, RF_IgnoreMissingEntries, &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.
+/// Insert all of the aliases in Src into the Dest module.
void ModuleLinker::linkAliasBodies() {
for (Module::alias_iterator I = SrcM->alias_begin(), E = SrcM->alias_end();
I != E; ++I) {
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);
}
}
}
-/// linkNamedMDNodes - Insert all of the named MDNodes in Src into the Dest
-/// module.
+/// Insert all of the named MDNodes in Src into the Dest module.
void ModuleLinker::linkNamedMDNodes() {
const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
for (Module::const_named_metadata_iterator I = SrcM->named_metadata_begin(),
}
}
-/// linkModuleFlagsMetadata - Merge the linker flags in Src into the Dest
-/// module.
+/// Merge the linker flags in Src into the Dest module.
bool ModuleLinker::linkModuleFlagsMetadata() {
// If the source module has no module flags, we are done.
const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
// 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)) {
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";
+ emitWarning("linking module flags '" + ID->getString() +
+ "': IDs have conflicting values");
}
continue;
}
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()) {
+ emitWarning("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";
+ emitWarning("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.
// Loop over all of the linked values to compute type mappings.
computeTypeMapping();
+ ComdatsChosen.clear();
+ for (const auto &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);
+ }
+
+ // Upgrade mismatched global arrays.
+ upgradeMismatchedGlobals();
+
// 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(),
E = SrcM->global_end(); I != E; ++I)
- if (linkGlobalProto(I))
+ if (linkGlobalValueProto(I))
return true;
// Link the functions together between the two modules, without doing function
// all of the global values that may be referenced are available in our
// ValueMap.
for (Module::iterator I = SrcM->begin(), E = SrcM->end(); I != E; ++I)
- if (linkFunctionProto(I))
+ if (linkGlobalValueProto(I))
return true;
// If there were any aliases, link them now.
for (Module::alias_iterator I = SrcM->alias_begin(),
E = SrcM->alias_end(); I != E; ++I)
- if (linkAliasProto(I))
+ if (linkGlobalValueProto(I))
return true;
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;
-
- // Skip if no body (function is external) or materialize.
- if (SF->isDeclaration()) {
- if (!SF->isMaterializable())
- continue;
- if (SF->Materialize(&ErrorMsg))
- return true;
+
+ Function *DF = cast<Function>(ValueMap[SF]);
+ if (SF->hasPrefixData()) {
+ // Link in the prefix data.
+ DF->setPrefixData(MapValue(
+ SF->getPrefixData(), ValueMap, RF_None, &TypeMap, &ValMaterializer));
}
-
- linkFunctionBody(cast<Function>(ValueMap[SF]), SF);
+
+ // Materialize if needed.
+ if (std::error_code EC = SF->materialize())
+ return emitError(EC.message());
+
+ // Skip if no body (function is external).
+ if (SF->isDeclaration())
+ continue;
+
+ linkFunctionBody(DF, SF);
SF->Dematerialize();
}
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;
Function *DF = cast<Function>(ValueMap[SF]);
-
- // Materialize if necessary.
- if (SF->isDeclaration()) {
- if (!SF->isMaterializable())
- continue;
- if (SF->Materialize(&ErrorMsg))
- return true;
+ if (SF->hasPrefixData()) {
+ // Link in the prefix data.
+ DF->setPrefixData(MapValue(SF->getPrefixData(),
+ ValueMap,
+ RF_None,
+ &TypeMap,
+ &ValMaterializer));
}
-
+
+ // Materialize if needed.
+ if (std::error_code EC = SF->materialize())
+ return emitError(EC.message());
+
+ // Skip if no body (function is external).
+ if (SF->isDeclaration())
+ continue;
+
// Erase from vector *before* the function body is linked - linkFunctionBody could
// invalidate I.
LazilyLinkFunctions.erase(I);
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) {
+void Linker::init(Module *M, DiagnosticHandlerFunction DiagnosticHandler) {
+ this->Composite = M;
+ this->DiagnosticHandler = DiagnosticHandler;
+
TypeFinder StructTypes;
StructTypes.run(*M, true);
IdentifiedStructTypes.insert(StructTypes.begin(), StructTypes.end());
}
+Linker::Linker(Module *M, DiagnosticHandlerFunction DiagnosticHandler) {
+ init(M, DiagnosticHandler);
+}
+
+Linker::Linker(Module *M) {
+ init(M, [this](const DiagnosticInfo &DI) {
+ Composite->getContext().diagnose(DI);
+ });
+}
+
Linker::~Linker() {
}
-bool Linker::linkInModule(Module *Src, unsigned Mode, std::string *ErrorMsg) {
- ModuleLinker TheLinker(Composite, IdentifiedStructTypes, Src, Mode);
- if (TheLinker.run()) {
- if (ErrorMsg)
- *ErrorMsg = TheLinker.ErrorMsg;
- return true;
- }
- return false;
+void Linker::deleteModule() {
+ delete Composite;
+ Composite = nullptr;
+}
+
+bool Linker::linkInModule(Module *Src) {
+ ModuleLinker TheLinker(Composite, IdentifiedStructTypes, Src,
+ DiagnosticHandler);
+ return TheLinker.run();
}
//===----------------------------------------------------------------------===//
// LinkModules entrypoint.
//===----------------------------------------------------------------------===//
-/// LinkModules - This function links two modules together, with the resulting
-/// Dest module modified to be the composite of the two input modules. If an
-/// 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,
- std::string *ErrorMsg) {
+/// This function links two modules together, with the resulting Dest module
+/// modified to be the composite of the two input modules. If an 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,
+ DiagnosticHandlerFunction DiagnosticHandler) {
+ Linker L(Dest, DiagnosticHandler);
+ return L.linkInModule(Src);
+}
+
+bool Linker::LinkModules(Module *Dest, Module *Src) {
Linker L(Dest);
- return L.linkInModule(Src, Mode, ErrorMsg);
+ return L.linkInModule(Src);
}
//===----------------------------------------------------------------------===//
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);
- if (OutMessages)
- *OutMessages = strdup(Messages.c_str());
+ Module *D = unwrap(Dest);
+ std::string Message;
+ raw_string_ostream Stream(Message);
+ DiagnosticPrinterRawOStream DP(Stream);
+
+ LLVMBool Result = Linker::LinkModules(
+ D, unwrap(Src), [&](const DiagnosticInfo &DI) { DI.print(DP); });
+
+ if (OutMessages && Result)
+ *OutMessages = strdup(Message.c_str());
return Result;
}