#include "llvm/Linker/Linker.h"
#include "llvm-c/Linker.h"
-#include "llvm/ADT/Hashing.h"
-#include "llvm/ADT/Optional.h"
#include "llvm/ADT/SetVector.h"
#include "llvm/ADT/SmallString.h"
-#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/Triple.h"
#include "llvm/IR/Constants.h"
-#include "llvm/IR/DebugInfo.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 {
class TypeMapTy : public ValueMapTypeRemapper {
/// This is a mapping from a source type to a destination type to use.
- DenseMap<Type*, Type*> MappedTypes;
+ DenseMap<Type *, Type *> MappedTypes;
/// When checking to see if two subgraphs are isomorphic, we speculatively
/// add types to MappedTypes, but keep track of them here in case we need to
/// roll back.
- SmallVector<Type*, 16> SpeculativeTypes;
+ SmallVector<Type *, 16> SpeculativeTypes;
- SmallVector<StructType*, 16> SpeculativeDstOpaqueTypes;
+ SmallVector<StructType *, 16> SpeculativeDstOpaqueTypes;
/// This is a list of non-opaque structs in the source module that are mapped
/// to an opaque struct in the destination module.
- SmallVector<StructType*, 16> SrcDefinitionsToResolve;
+ SmallVector<StructType *, 16> SrcDefinitionsToResolve;
/// This is the set of opaque types in the destination modules who are
/// getting a body from the source module.
- SmallPtrSet<StructType*, 16> DstResolvedOpaqueTypes;
+ SmallPtrSet<StructType *, 16> DstResolvedOpaqueTypes;
public:
TypeMapTy(Linker::IdentifiedStructTypeSet &DstStructTypesSet)
// Fail if any of the extra properties (e.g. array size) of the type disagree.
if (isa<IntegerType>(DstTy))
- return false; // bitwidth disagrees.
+ return false; // bitwidth disagrees.
if (PointerType *PT = dyn_cast<PointerType>(DstTy)) {
if (PT->getAddressSpace() != cast<PointerType>(SrcTy)->getAddressSpace())
return false;
}
void TypeMapTy::linkDefinedTypeBodies() {
- SmallVector<Type*, 16> Elements;
+ SmallVector<Type *, 16> Elements;
for (StructType *SrcSTy : SrcDefinitionsToResolve) {
StructType *DstSTy = cast<StructType>(MappedTypes[SrcSTy]);
assert(DstSTy->isOpaque());
/// speeds up linking for modules with many/ lazily linked functions of which
/// few get used.
class ValueMaterializerTy final : public ValueMaterializer {
- TypeMapTy &TypeMap;
- Module *DstM;
- std::vector<GlobalValue *> &LazilyLinkGlobalValues;
ModuleLinker *ModLinker;
public:
- ValueMaterializerTy(TypeMapTy &TypeMap, Module *DstM,
- std::vector<GlobalValue *> &LazilyLinkGlobalValues,
- ModuleLinker *ModLinker)
- : ValueMaterializer(), TypeMap(TypeMap), DstM(DstM),
- LazilyLinkGlobalValues(LazilyLinkGlobalValues), ModLinker(ModLinker) {}
+ ValueMaterializerTy(ModuleLinker *ModLinker) : ModLinker(ModLinker) {}
- Value *materializeValueFor(Value *V) override;
+ Value *materializeDeclFor(Value *V) override;
+ void materializeInitFor(GlobalValue *New, GlobalValue *Old) override;
};
class LinkDiagnosticInfo : public DiagnosticInfo {
/// This is an implementation class for the LinkModules function, which is the
/// entrypoint for this file.
class ModuleLinker {
- Module *DstM, *SrcM;
+ Module &DstM;
+ Module &SrcM;
TypeMapTy TypeMap;
ValueMaterializerTy ValMaterializer;
/// but this allows us to reuse the ValueMapper code.
ValueToValueMapTy ValueMap;
- struct AppendingVarInfo {
- 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;
-
- // Set of items not to link in from source.
- SmallPtrSet<const Value *, 16> DoNotLinkFromSource;
-
- // Vector of GlobalValues to lazily link in.
- std::vector<GlobalValue *> LazilyLinkGlobalValues;
+ SetVector<GlobalValue *> ValuesToLink;
DiagnosticHandlerFunction DiagnosticHandler;
/// Function index passed into ModuleLinker for using in function
/// importing/exporting handling.
- FunctionInfoIndex *ImportIndex;
+ const FunctionInfoIndex *ImportIndex;
/// Function to import from source module, all other functions are
/// imported as declarations instead of definitions.
- Function *ImportFunction;
+ DenseSet<const GlobalValue *> *ImportFunction;
/// Set to true if the given FunctionInfoIndex contains any functions
/// from this source module, in which case we must conservatively assume
/// that any of its functions may be imported into another module
/// as part of a different backend compilation process.
- bool HasExportedFunctions;
+ bool HasExportedFunctions = false;
/// Set to true when all global value body linking is complete (including
/// lazy linking). Used to prevent metadata linking from creating new
/// references.
- bool DoneLinkingBodies;
+ bool DoneLinkingBodies = false;
+
+ bool HasError = false;
public:
- ModuleLinker(Module *dstM, Linker::IdentifiedStructTypeSet &Set, Module *srcM,
+ ModuleLinker(Module &DstM, Linker::IdentifiedStructTypeSet &Set, Module &SrcM,
DiagnosticHandlerFunction DiagnosticHandler, unsigned Flags,
- FunctionInfoIndex *Index = nullptr,
- Function *FuncToImport = nullptr)
- : DstM(dstM), SrcM(srcM), TypeMap(Set),
- ValMaterializer(TypeMap, DstM, LazilyLinkGlobalValues, this),
+ const FunctionInfoIndex *Index = nullptr,
+ DenseSet<const GlobalValue *> *FunctionsToImport = nullptr)
+ : DstM(DstM), SrcM(SrcM), TypeMap(Set), ValMaterializer(this),
DiagnosticHandler(DiagnosticHandler), Flags(Flags), ImportIndex(Index),
- ImportFunction(FuncToImport), HasExportedFunctions(false),
- DoneLinkingBodies(false) {
+ ImportFunction(FunctionsToImport) {
assert((ImportIndex || !ImportFunction) &&
"Expect a FunctionInfoIndex when importing");
// If we have a FunctionInfoIndex but no function to import,
}
bool run();
+ Value *materializeDeclFor(Value *V);
+ void materializeInitFor(GlobalValue *New, GlobalValue *Old);
+private:
bool shouldOverrideFromSrc() { return Flags & Linker::OverrideFromSrc; }
bool shouldLinkOnlyNeeded() { return Flags & Linker::LinkOnlyNeeded; }
bool shouldInternalizeLinkedSymbols() {
/// Handles cloning of a global values from the source module into
/// the destination module, including setting the attributes and visibility.
- GlobalValue *copyGlobalValueProto(TypeMapTy &TypeMap, const GlobalValue *SGV,
- const GlobalValue *DGV = nullptr);
+ GlobalValue *copyGlobalValueProto(const GlobalValue *SGV,
+ const GlobalValue *DGV, bool ForDefinition);
/// Check if we should promote the given local value to global scope.
bool doPromoteLocalToGlobal(const GlobalValue *SGV);
- /// Check if all global value body linking is complete.
- bool doneLinkingBodies() { return DoneLinkingBodies; }
-
-private:
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) {
DiagnosticHandler(LinkDiagnosticInfo(DS_Error, Message));
+ HasError = true;
return true;
}
DiagnosticHandler(LinkDiagnosticInfo(DS_Warning, Message));
}
- bool getComdatLeader(Module *M, StringRef ComdatName,
+ bool getComdatLeader(Module &M, StringRef ComdatName,
const GlobalVariable *&GVar);
bool computeResultingSelectionKind(StringRef ComdatName,
Comdat::SelectionKind Src,
ComdatsChosen;
bool getComdatResult(const Comdat *SrcC, Comdat::SelectionKind &SK,
bool &LinkFromSrc);
+ // Keep track of the global value members of each comdat in source.
+ DenseMap<const Comdat *, std::vector<GlobalValue *>> ComdatMembers;
/// 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())
+ if (!SrcGV->hasName() || GlobalValue::isLocalLinkage(getLinkage(SrcGV)))
return nullptr;
// Otherwise see if we have a match in the destination module's symtab.
- GlobalValue *DGV = DstM->getNamedValue(SrcGV->getName());
+ GlobalValue *DGV = DstM.getNamedValue(getName(SrcGV));
if (!DGV)
return nullptr;
void upgradeMismatchedGlobalArray(StringRef Name);
void upgradeMismatchedGlobals();
- bool linkAppendingVarProto(GlobalVariable *DstGV,
- const GlobalVariable *SrcGV);
+ bool linkIfNeeded(GlobalValue &GV);
+ Constant *linkAppendingVarProto(GlobalVariable *DstGV,
+ const GlobalVariable *SrcGV);
- bool linkGlobalValueProto(GlobalValue *GV);
+ Constant *linkGlobalValueProto(GlobalValue *GV);
bool linkModuleFlagsMetadata();
- void linkAppendingVarInit(const AppendingVarInfo &AVI);
-
void linkGlobalInit(GlobalVariable &Dst, GlobalVariable &Src);
bool linkFunctionBody(Function &Dst, Function &Src);
void linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src);
- bool linkGlobalValueBody(GlobalValue &Src);
+ bool linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src);
/// Functions that take care of cloning a specific global value type
/// into the destination module.
- GlobalVariable *copyGlobalVariableProto(TypeMapTy &TypeMap,
- const GlobalVariable *SGVar);
- Function *copyFunctionProto(TypeMapTy &TypeMap, const Function *SF);
- GlobalValue *copyGlobalAliasProto(TypeMapTy &TypeMap, const GlobalAlias *SGA);
+ GlobalVariable *copyGlobalVariableProto(const GlobalVariable *SGVar);
+ Function *copyFunctionProto(const Function *SF);
+ GlobalValue *copyGlobalAliasProto(const GlobalAlias *SGA);
/// Helper methods to check if we are importing from or potentially
/// exporting from the current source module.
// If there is a conflict, rename the conflict.
if (GlobalValue *ConflictGV = M->getNamedValue(Name)) {
GV->takeName(ConflictGV);
- ConflictGV->setName(Name); // This will cause ConflictGV to get renamed
+ ConflictGV->setName(Name); // This will cause ConflictGV to get renamed
assert(ConflictGV->getName() != Name && "forceRenaming didn't work");
} else {
- GV->setName(Name); // Force the name back
+ GV->setName(Name); // Force the name back
}
}
/// from the SrcGV to the DestGV.
void ModuleLinker::copyGVAttributes(GlobalValue *NewGV,
const GlobalValue *SrcGV) {
- auto *GA = dyn_cast<GlobalAlias>(SrcGV);
- // Check for the special case of converting an alias (definition) to a
- // non-alias (declaration). This can happen when we are importing and
- // encounter a weak_any alias (weak_any defs may not be imported, see
- // comments in ModuleLinker::getLinkage) or an alias whose base object is
- // being imported as a declaration. In that case copy the attributes from the
- // base object.
- if (GA && !dyn_cast<GlobalAlias>(NewGV)) {
- assert(isPerformingImport() &&
- (GA->hasWeakAnyLinkage() ||
- !doImportAsDefinition(GA->getBaseObject())));
- NewGV->copyAttributesFrom(GA->getBaseObject());
- } else
- NewGV->copyAttributesFrom(SrcGV);
+ NewGV->copyAttributesFrom(SrcGV);
forceRenaming(NewGV, getName(SrcGV));
}
-static bool isLessConstraining(GlobalValue::VisibilityTypes a,
- GlobalValue::VisibilityTypes b) {
- if (a == GlobalValue::HiddenVisibility)
- return false;
- if (b == GlobalValue::HiddenVisibility)
- return true;
- if (a == GlobalValue::ProtectedVisibility)
- return false;
- if (b == GlobalValue::ProtectedVisibility)
- return true;
- return false;
-}
-
bool ModuleLinker::doImportAsDefinition(const GlobalValue *SGV) {
if (!isPerformingImport())
return false;
- // Always import GlobalVariable definitions. The linkage changes
+ auto *GA = dyn_cast<GlobalAlias>(SGV);
+ if (GA) {
+ if (GA->hasWeakAnyLinkage())
+ return false;
+ const GlobalObject *GO = GA->getBaseObject();
+ if (!GO->hasLinkOnceODRLinkage())
+ return false;
+ return doImportAsDefinition(GO);
+ }
+ // Always import GlobalVariable definitions, except for the special
+ // case of WeakAny which are imported as ExternalWeak declarations
+ // (see comments in ModuleLinker::getLinkage). The linkage changes
// described in ModuleLinker::getLinkage ensure the correct behavior (e.g.
// global variables with external linkage are transformed to
- // available_externally defintions, which are ultimately turned into
- // declaratios after the EliminateAvailableExternally pass).
- if (dyn_cast<GlobalVariable>(SGV) && !SGV->isDeclaration())
+ // available_externally definitions, which are ultimately turned into
+ // declarations after the EliminateAvailableExternally pass).
+ if (isa<GlobalVariable>(SGV) && !SGV->isDeclaration() &&
+ !SGV->hasWeakAnyLinkage())
return true;
// Only import the function requested for importing.
auto *SF = dyn_cast<Function>(SGV);
- if (SF && SF == ImportFunction)
+ if (SF && ImportFunction->count(SF))
return true;
// Otherwise no.
return false;
// definitions upon import, so that they are available for inlining
// and/or optimization, but are turned into declarations later
// during the EliminateAvailableExternally pass.
- if (doImportAsDefinition(SGV))
+ if (doImportAsDefinition(SGV) && !dyn_cast<GlobalAlias>(SGV))
return GlobalValue::AvailableExternallyLinkage;
// An imported external declaration stays external.
return SGV->getLinkage();
// equivalent, so the issue described above for weak_any does not exist,
// and the definition can be imported. It can be treated similarly
// to an imported externally visible global value.
- if (doImportAsDefinition(SGV))
+ if (doImportAsDefinition(SGV) && !dyn_cast<GlobalAlias>(SGV))
return GlobalValue::AvailableExternallyLinkage;
else
return GlobalValue::ExternalLinkage;
// It would be incorrect to import an appending linkage variable,
// since it would cause global constructors/destructors to be
// executed multiple times. This should have already been handled
- // by linkGlobalValueProto.
- assert(false && "Cannot import appending linkage variable");
+ // by linkIfNeeded, and we will assert in shouldLinkFromSource
+ // if we try to import, so we simply return AppendingLinkage here
+ // as this helper is called more widely in getLinkedToGlobal.
+ return GlobalValue::AppendingLinkage;
case GlobalValue::InternalLinkage:
case GlobalValue::PrivateLinkage:
// If we are promoting the local to global scope, it is handled
// similarly to a normal externally visible global.
if (doPromoteLocalToGlobal(SGV)) {
- if (doImportAsDefinition(SGV))
+ if (doImportAsDefinition(SGV) && !dyn_cast<GlobalAlias>(SGV))
return GlobalValue::AvailableExternallyLinkage;
else
return GlobalValue::ExternalLinkage;
/// Loop through the global variables in the src module and merge them into the
/// dest module.
GlobalVariable *
-ModuleLinker::copyGlobalVariableProto(TypeMapTy &TypeMap,
- const GlobalVariable *SGVar) {
+ModuleLinker::copyGlobalVariableProto(const GlobalVariable *SGVar) {
// No linking to be performed or linking from the source: simply create an
// identical version of the symbol over in the dest module... the
// initializer will be filled in later by LinkGlobalInits.
- GlobalVariable *NewDGV = new GlobalVariable(
- *DstM, TypeMap.get(SGVar->getType()->getElementType()),
- SGVar->isConstant(), getLinkage(SGVar), /*init*/ nullptr, getName(SGVar),
- /*insertbefore*/ nullptr, SGVar->getThreadLocalMode(),
- SGVar->getType()->getAddressSpace());
+ GlobalVariable *NewDGV =
+ new GlobalVariable(DstM, TypeMap.get(SGVar->getType()->getElementType()),
+ SGVar->isConstant(), GlobalValue::ExternalLinkage,
+ /*init*/ nullptr, getName(SGVar),
+ /*insertbefore*/ nullptr, SGVar->getThreadLocalMode(),
+ SGVar->getType()->getAddressSpace());
return NewDGV;
}
/// Link the function in the source module into the destination module if
/// needed, setting up mapping information.
-Function *ModuleLinker::copyFunctionProto(TypeMapTy &TypeMap,
- const Function *SF) {
+Function *ModuleLinker::copyFunctionProto(const Function *SF) {
// If there is no linkage to be performed or we are linking from the source,
// bring SF over.
- return Function::Create(TypeMap.get(SF->getFunctionType()), getLinkage(SF),
- getName(SF), DstM);
+ return Function::Create(TypeMap.get(SF->getFunctionType()),
+ GlobalValue::ExternalLinkage, getName(SF), &DstM);
}
/// Set up prototypes for any aliases that come over from the source module.
-GlobalValue *ModuleLinker::copyGlobalAliasProto(TypeMapTy &TypeMap,
- const GlobalAlias *SGA) {
- // If we are importing and encounter a weak_any alias, or an alias to
- // an object being imported as a declaration, we must import the alias
- // as a declaration as well, which involves converting it to a non-alias.
- // See comments in ModuleLinker::getLinkage for why we cannot import
- // weak_any defintions.
- if (isPerformingImport() && (SGA->hasWeakAnyLinkage() ||
- !doImportAsDefinition(SGA->getBaseObject()))) {
- // Need to convert to declaration. All aliases must be definitions.
- const GlobalValue *GVal = SGA->getBaseObject();
- GlobalValue *NewGV;
- if (auto *GVar = dyn_cast<GlobalVariable>(GVal))
- NewGV = copyGlobalVariableProto(TypeMap, GVar);
- else {
- auto *F = dyn_cast<Function>(GVal);
- assert(F);
- NewGV = copyFunctionProto(TypeMap, F);
- }
- // Set the linkage to External or ExternalWeak (see comments in
- // ModuleLinker::getLinkage for why WeakAny is converted to ExternalWeak).
- if (SGA->hasWeakAnyLinkage())
- NewGV->setLinkage(GlobalValue::ExternalWeakLinkage);
- else
- NewGV->setLinkage(GlobalValue::ExternalLinkage);
- // Don't attempt to link body, needs to be a declaration.
- DoNotLinkFromSource.insert(SGA);
- return NewGV;
- }
+GlobalValue *ModuleLinker::copyGlobalAliasProto(const GlobalAlias *SGA) {
// If there is no linkage to be performed or we're linking from the source,
// bring over SGA.
auto *Ty = TypeMap.get(SGA->getValueType());
return GlobalAlias::create(Ty, SGA->getType()->getPointerAddressSpace(),
- getLinkage(SGA), getName(SGA), DstM);
+ GlobalValue::ExternalLinkage, getName(SGA), &DstM);
+}
+
+static GlobalValue::VisibilityTypes
+getMinVisibility(GlobalValue::VisibilityTypes A,
+ GlobalValue::VisibilityTypes B) {
+ if (A == GlobalValue::HiddenVisibility || B == GlobalValue::HiddenVisibility)
+ return GlobalValue::HiddenVisibility;
+ if (A == GlobalValue::ProtectedVisibility ||
+ B == GlobalValue::ProtectedVisibility)
+ return GlobalValue::ProtectedVisibility;
+ return GlobalValue::DefaultVisibility;
}
void ModuleLinker::setVisibility(GlobalValue *NewGV, const GlobalValue *SGV,
const GlobalValue *DGV) {
GlobalValue::VisibilityTypes Visibility = SGV->getVisibility();
if (DGV)
- Visibility = isLessConstraining(Visibility, DGV->getVisibility())
- ? DGV->getVisibility()
- : Visibility;
+ Visibility = getMinVisibility(DGV->getVisibility(), Visibility);
// For promoted locals, mark them hidden so that they can later be
// stripped from the symbol table to reduce bloat.
if (SGV->hasLocalLinkage() && doPromoteLocalToGlobal(SGV))
NewGV->setVisibility(Visibility);
}
-GlobalValue *ModuleLinker::copyGlobalValueProto(TypeMapTy &TypeMap,
- const GlobalValue *SGV,
- const GlobalValue *DGV) {
+GlobalValue *ModuleLinker::copyGlobalValueProto(const GlobalValue *SGV,
+ const GlobalValue *DGV,
+ bool ForDefinition) {
GlobalValue *NewGV;
- if (auto *SGVar = dyn_cast<GlobalVariable>(SGV))
- NewGV = copyGlobalVariableProto(TypeMap, SGVar);
- else if (auto *SF = dyn_cast<Function>(SGV))
- NewGV = copyFunctionProto(TypeMap, SF);
- else
- NewGV = copyGlobalAliasProto(TypeMap, cast<GlobalAlias>(SGV));
+ 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->getType()->getElementType()),
+ /*isConstant*/ false, GlobalValue::ExternalLinkage,
+ /*init*/ nullptr, getName(SGV),
+ /*insertbefore*/ nullptr, SGV->getThreadLocalMode(),
+ SGV->getType()->getAddressSpace());
+ }
+
+ if (ForDefinition)
+ NewGV->setLinkage(getLinkage(SGV));
+ else if (SGV->hasAvailableExternallyLinkage() || SGV->hasWeakLinkage() ||
+ SGV->hasLinkOnceLinkage())
+ NewGV->setLinkage(GlobalValue::ExternalWeakLinkage);
+
copyGVAttributes(NewGV, SGV);
setVisibility(NewGV, SGV, DGV);
return NewGV;
}
-Value *ValueMaterializerTy::materializeValueFor(Value *V) {
+Value *ValueMaterializerTy::materializeDeclFor(Value *V) {
+ return ModLinker->materializeDeclFor(V);
+}
+
+Value *ModuleLinker::materializeDeclFor(Value *V) {
auto *SGV = dyn_cast<GlobalValue>(V);
if (!SGV)
return nullptr;
- // If we are done linking global value bodies (i.e. we are performing
- // metadata linking), don't link in the global value due to this
- // reference, simply map it to null.
- if (ModLinker->doneLinkingBodies())
- return nullptr;
+ return linkGlobalValueProto(SGV);
+}
- GlobalValue *DGV = ModLinker->copyGlobalValueProto(TypeMap, SGV);
+void ValueMaterializerTy::materializeInitFor(GlobalValue *New,
+ GlobalValue *Old) {
+ return ModLinker->materializeInitFor(New, Old);
+}
- if (Comdat *SC = SGV->getComdat()) {
- if (auto *DGO = dyn_cast<GlobalObject>(DGV)) {
- Comdat *DC = DstM->getOrInsertComdat(SC->getName());
- DGO->setComdat(DC);
- }
+static bool shouldLazyLink(const GlobalValue &GV) {
+ return GV.hasLocalLinkage() || GV.hasLinkOnceLinkage() ||
+ GV.hasAvailableExternallyLinkage();
+}
+
+void ModuleLinker::materializeInitFor(GlobalValue *New, GlobalValue *Old) {
+ if (auto *F = dyn_cast<Function>(New)) {
+ if (!F->isDeclaration())
+ return;
+ } else if (auto *V = dyn_cast<GlobalVariable>(New)) {
+ if (V->hasInitializer())
+ return;
+ } else {
+ auto *A = cast<GlobalAlias>(New);
+ if (A->getAliasee())
+ return;
}
- LazilyLinkGlobalValues.push_back(SGV);
- return DGV;
+ if (Old->isDeclaration())
+ return;
+
+ if (isPerformingImport() && !doImportAsDefinition(Old))
+ return;
+
+ if (!ValuesToLink.count(Old) && !shouldLazyLink(*Old))
+ return;
+
+ linkGlobalValueBody(*New, *Old);
}
-bool ModuleLinker::getComdatLeader(Module *M, StringRef ComdatName,
+bool ModuleLinker::getComdatLeader(Module &M, StringRef ComdatName,
const GlobalVariable *&GVar) {
- const GlobalValue *GVal = M->getNamedValue(ComdatName);
+ const GlobalValue *GVal = M.getNamedValue(ComdatName);
if (const auto *GA = dyn_cast_or_null<GlobalAlias>(GVal)) {
GVal = GA->getBaseObject();
if (!GVal)
getComdatLeader(SrcM, ComdatName, SrcGV))
return true;
- const DataLayout &DstDL = DstM->getDataLayout();
- const DataLayout &SrcDL = SrcM->getDataLayout();
+ const DataLayout &DstDL = DstM.getDataLayout();
+ const DataLayout &SrcDL = SrcM.getDataLayout();
uint64_t DstSize =
DstDL.getTypeAllocSize(DstGV->getType()->getPointerElementType());
uint64_t SrcSize =
bool &LinkFromSrc) {
Comdat::SelectionKind SSK = SrcC->getSelectionKind();
StringRef ComdatName = SrcC->getName();
- Module::ComdatSymTabType &ComdatSymTab = DstM->getComdatSymbolTable();
+ Module::ComdatSymTabType &ComdatSymTab = DstM.getComdatSymbolTable();
Module::ComdatSymTabType::iterator DstCI = ComdatSymTab.find(ComdatName);
if (DstCI == ComdatSymTab.end()) {
// We always have to add Src if it has appending linkage.
if (Src.hasAppendingLinkage()) {
- // Caller should have already determined that we can't link from source
- // when importing (see comments in linkGlobalValueProto).
+ // Should have prevented importing for appending linkage in linkIfNeeded.
assert(!isPerformingImport());
LinkFromSrc = true;
return false;
if (isa<Function>(&Src)) {
// For functions, LinkFromSrc iff this is the function requested
// for importing. For variables, decide below normally.
- LinkFromSrc = (&Src == ImportFunction);
+ LinkFromSrc = ImportFunction->count(&Src);
return false;
}
/// types 'Foo' but one got renamed when the module was loaded into the same
/// LLVMContext.
void ModuleLinker::computeTypeMapping() {
- for (GlobalValue &SGV : SrcM->globals()) {
+ for (GlobalValue &SGV : SrcM.globals()) {
GlobalValue *DGV = getLinkedToGlobal(&SGV);
if (!DGV)
continue;
TypeMap.addTypeMapping(DAT->getElementType(), SAT->getElementType());
}
- for (GlobalValue &SGV : *SrcM) {
+ for (GlobalValue &SGV : SrcM) {
if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
}
- for (GlobalValue &SGV : SrcM->aliases()) {
+ for (GlobalValue &SGV : SrcM.aliases()) {
if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
}
// At this point, the destination module may have a type "%foo = { i32 }" for
// example. When the source module got loaded into the same LLVMContext, if
// it had the same type, it would have been renamed to "%foo.42 = { i32 }".
- std::vector<StructType *> Types = SrcM->getIdentifiedStructTypes();
+ std::vector<StructType *> Types = SrcM.getIdentifiedStructTypes();
for (StructType *ST : Types) {
if (!ST->hasName())
continue;
continue;
// Check to see if the destination module has a struct with the prefix name.
- StructType *DST = DstM->getTypeByName(ST->getName().substr(0, DotPos));
+ StructType *DST = DstM.getTypeByName(ST->getName().substr(0, DotPos));
if (!DST)
continue;
void ModuleLinker::upgradeMismatchedGlobalArray(StringRef Name) {
// Look for the global arrays.
- auto *DstGV = dyn_cast_or_null<GlobalVariable>(DstM->getNamedValue(Name));
+ auto *DstGV = dyn_cast_or_null<GlobalVariable>(DstM.getNamedValue(Name));
if (!DstGV)
return;
- auto *SrcGV = dyn_cast_or_null<GlobalVariable>(SrcM->getNamedValue(Name));
+ auto *SrcGV = dyn_cast_or_null<GlobalVariable>(SrcM.getNamedValue(Name));
if (!SrcGV)
return;
upgradeMismatchedGlobalArray("llvm.global_dtors");
}
+static void getArrayElements(const Constant *C,
+ SmallVectorImpl<Constant *> &Dest) {
+ unsigned NumElements = cast<ArrayType>(C->getType())->getNumElements();
+
+ for (unsigned i = 0; i != NumElements; ++i)
+ Dest.push_back(C->getAggregateElement(i));
+}
+
/// If there were any appending global variables, link them together now.
/// Return true on error.
-bool ModuleLinker::linkAppendingVarProto(GlobalVariable *DstGV,
- const GlobalVariable *SrcGV) {
+Constant *ModuleLinker::linkAppendingVarProto(GlobalVariable *DstGV,
+ const GlobalVariable *SrcGV) {
+ ArrayType *SrcTy =
+ cast<ArrayType>(TypeMap.get(SrcGV->getType()->getElementType()));
+ Type *EltTy = SrcTy->getElementType();
- if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage())
- return emitError("Linking globals named '" + SrcGV->getName() +
- "': can only link appending global with another appending global!");
+ if (DstGV) {
+ ArrayType *DstTy = cast<ArrayType>(DstGV->getType()->getElementType());
- ArrayType *DstTy = cast<ArrayType>(DstGV->getType()->getElementType());
- ArrayType *SrcTy =
- cast<ArrayType>(TypeMap.get(SrcGV->getType()->getElementType()));
- Type *EltTy = DstTy->getElementType();
+ if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage()) {
+ emitError(
+ "Linking globals named '" + SrcGV->getName() +
+ "': can only link appending global with another appending global!");
+ return nullptr;
+ }
- // 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!");
+ // Check to see that they two arrays agree on type.
+ 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())
- return emitError(
- "Appending variables with different alignment need to be linked!");
+ if (DstGV->getAlignment() != SrcGV->getAlignment()) {
+ emitError(
+ "Appending variables with different alignment need to be linked!");
+ return nullptr;
+ }
- if (DstGV->getVisibility() != SrcGV->getVisibility())
- return emitError(
- "Appending variables with different visibility need to be linked!");
+ if (DstGV->getVisibility() != SrcGV->getVisibility()) {
+ emitError(
+ "Appending variables with different visibility need to be linked!");
+ return nullptr;
+ }
- if (DstGV->hasUnnamedAddr() != SrcGV->hasUnnamedAddr())
- return emitError(
- "Appending variables with different unnamed_addr need to be linked!");
+ if (DstGV->hasUnnamedAddr() != SrcGV->hasUnnamedAddr()) {
+ emitError(
+ "Appending variables with different unnamed_addr need to be linked!");
+ return nullptr;
+ }
- if (StringRef(DstGV->getSection()) != SrcGV->getSection())
- return emitError(
+ if (StringRef(DstGV->getSection()) != SrcGV->getSection()) {
+ emitError(
"Appending variables with different section name need to be linked!");
+ return nullptr;
+ }
+ }
+
+ SmallVector<Constant *, 16> DstElements;
+ if (DstGV)
+ getArrayElements(DstGV->getInitializer(), DstElements);
+
+ SmallVector<Constant *, 16> SrcElements;
+ getArrayElements(SrcGV->getInitializer(), SrcElements);
- uint64_t NewSize = DstTy->getNumElements() + SrcTy->getNumElements();
+ StringRef Name = SrcGV->getName();
+ bool IsNewStructor =
+ (Name == "llvm.global_ctors" || Name == "llvm.global_dtors") &&
+ cast<StructType>(EltTy)->getNumElements() == 3;
+ if (IsNewStructor)
+ SrcElements.erase(
+ std::remove_if(SrcElements.begin(), SrcElements.end(),
+ [this](Constant *E) {
+ auto *Key = dyn_cast<GlobalValue>(
+ E->getAggregateElement(2)->stripPointerCasts());
+ return Key && !ValuesToLink.count(Key) &&
+ !shouldLazyLink(*Key);
+ }),
+ SrcElements.end());
+ uint64_t NewSize = DstElements.size() + SrcElements.size();
ArrayType *NewType = ArrayType::get(EltTy, NewSize);
// Create the new global variable.
- GlobalVariable *NG =
- new GlobalVariable(*DstGV->getParent(), NewType, SrcGV->isConstant(),
- DstGV->getLinkage(), /*init*/nullptr, /*name*/"", DstGV,
- DstGV->getThreadLocalMode(),
- DstGV->getType()->getAddressSpace());
+ GlobalVariable *NG = new GlobalVariable(
+ DstM, NewType, SrcGV->isConstant(), SrcGV->getLinkage(),
+ /*init*/ nullptr, /*name*/ "", DstGV, SrcGV->getThreadLocalMode(),
+ SrcGV->getType()->getAddressSpace());
// Propagate alignment, visibility and section info.
- copyGVAttributes(NG, DstGV);
+ copyGVAttributes(NG, SrcGV);
- AppendingVarInfo AVI;
- AVI.NewGV = NG;
- AVI.DstInit = DstGV->getInitializer();
- AVI.SrcInit = SrcGV->getInitializer();
- AppendingVars.push_back(AVI);
+ Constant *Ret = ConstantExpr::getBitCast(NG, TypeMap.get(SrcGV->getType()));
- // Replace any uses of the two global variables with uses of the new
- // global.
- ValueMap[SrcGV] = ConstantExpr::getBitCast(NG, TypeMap.get(SrcGV->getType()));
+ // Stop recursion.
+ ValueMap[SrcGV] = Ret;
- DstGV->replaceAllUsesWith(ConstantExpr::getBitCast(NG, DstGV->getType()));
- DstGV->eraseFromParent();
+ for (auto *V : SrcElements) {
+ DstElements.push_back(
+ MapValue(V, ValueMap, RF_MoveDistinctMDs, &TypeMap, &ValMaterializer));
+ }
- // Track the source variable so we don't try to link it.
- DoNotLinkFromSource.insert(SrcGV);
+ NG->setInitializer(ConstantArray::get(NewType, DstElements));
- return false;
+ // Replace any uses of the two global variables with uses of the new
+ // global.
+ if (DstGV) {
+ DstGV->replaceAllUsesWith(ConstantExpr::getBitCast(NG, DstGV->getType()));
+ DstGV->eraseFromParent();
+ }
+
+ return Ret;
}
-bool ModuleLinker::linkGlobalValueProto(GlobalValue *SGV) {
+Constant *ModuleLinker::linkGlobalValueProto(GlobalValue *SGV) {
GlobalValue *DGV = getLinkedToGlobal(SGV);
// Handle the ultra special appending linkage case first.
assert(!DGV || SGV->hasAppendingLinkage() == DGV->hasAppendingLinkage());
- if (SGV->hasAppendingLinkage() && isPerformingImport()) {
- // Don't want to append to global_ctors list, for example, when we
- // are importing for ThinLTO, otherwise the global ctors and dtors
- // get executed multiple times for local variables (the latter causing
- // double frees).
- DoNotLinkFromSource.insert(SGV);
- return false;
- }
- if (DGV && DGV->hasAppendingLinkage())
- return linkAppendingVarProto(cast<GlobalVariable>(DGV),
+ if (SGV->hasAppendingLinkage()) {
+ // Should have prevented importing for appending linkage in linkIfNeeded.
+ assert(!isPerformingImport());
+ return linkAppendingVarProto(cast_or_null<GlobalVariable>(DGV),
cast<GlobalVariable>(SGV));
+ }
bool LinkFromSrc = true;
Comdat *C = nullptr;
bool HasUnnamedAddr = SGV->hasUnnamedAddr();
- if (const Comdat *SC = SGV->getComdat()) {
+ if (isPerformingImport() && !doImportAsDefinition(SGV)) {
+ LinkFromSrc = false;
+ } else if (const Comdat *SC = SGV->getComdat()) {
Comdat::SelectionKind SK;
std::tie(SK, LinkFromSrc) = ComdatsChosen[SC];
- C = DstM->getOrInsertComdat(SC->getName());
+ C = DstM.getOrInsertComdat(SC->getName());
C->setSelectionKind(SK);
+ if (SGV->hasLocalLinkage())
+ LinkFromSrc = true;
} else if (DGV) {
if (shouldLinkFromSource(LinkFromSrc, *DGV, *SGV))
- return true;
- }
-
- 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()));
+ return nullptr;
}
if (DGV)
HasUnnamedAddr = HasUnnamedAddr && DGV->hasUnnamedAddr();
- if (!LinkFromSrc && !DGV)
- return false;
-
GlobalValue *NewGV;
- if (!LinkFromSrc) {
+ if (!LinkFromSrc && DGV) {
NewGV = DGV;
// When linking from source we setVisibility from copyGlobalValueProto.
setVisibility(NewGV, SGV, DGV);
} else {
- // If the GV is to be lazily linked, don't create it just yet.
- // The ValueMaterializerTy will deal with creating it if it's used.
- if (!DGV && !shouldOverrideFromSrc() && SGV != ImportFunction &&
- (SGV->hasLocalLinkage() || SGV->hasLinkOnceLinkage() ||
- SGV->hasAvailableExternallyLinkage())) {
- DoNotLinkFromSource.insert(SGV);
- return false;
- }
-
- // When we only want to link in unresolved dependencies, blacklist
- // the symbol unless unless DestM has a matching declaration (DGV).
- if (shouldLinkOnlyNeeded() && !(DGV && DGV->isDeclaration())) {
- DoNotLinkFromSource.insert(SGV);
- return false;
- }
+ // If we are done linking global value bodies (i.e. we are performing
+ // metadata linking), don't link in the global value due to this
+ // reference, simply map it to null.
+ if (DoneLinkingBodies)
+ return nullptr;
- NewGV = copyGlobalValueProto(TypeMap, SGV, DGV);
+ NewGV = copyGlobalValueProto(SGV, DGV, LinkFromSrc);
}
NewGV->setUnnamedAddr(HasUnnamedAddr);
if (auto *NewGO = dyn_cast<GlobalObject>(NewGV)) {
- if (C)
+ if (C && LinkFromSrc)
NewGO->setComdat(C);
if (DGV && DGV->hasCommonLinkage() && SGV->hasCommonLinkage())
NewGVar->setConstant(false);
}
- // 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;
-}
-
-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> DstElements;
- getArrayElements(AVI.DstInit, DstElements);
-
- SmallVector<Constant *, 16> SrcElements;
- getArrayElements(AVI.SrcInit, SrcElements);
-
- ArrayType *NewType = cast<ArrayType>(AVI.NewGV->getType()->getElementType());
-
- 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_MoveDistinctMDs, &TypeMap, &ValMaterializer));
- }
- if (IsNewStructor) {
- NewType = ArrayType::get(NewType->getElementType(), DstElements.size());
- AVI.NewGV->mutateType(PointerType::get(NewType, 0));
+ if (NewGV != DGV && DGV) {
+ DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewGV, DGV->getType()));
+ DGV->eraseFromParent();
}
- AVI.NewGV->setInitializer(ConstantArray::get(NewType, DstElements));
+ return ConstantExpr::getBitCast(NewGV, TypeMap.get(SGV->getType()));
}
/// Update the initializers in the Dest module now that all globals that may be
// Go through and convert function arguments over, remembering the mapping.
Function::arg_iterator DI = Dst.arg_begin();
for (Argument &Arg : Src.args()) {
- DI->setName(Arg.getName()); // Copy the name over.
+ DI->setName(Arg.getName()); // Copy the name over.
// Add a mapping to our mapping.
ValueMap[&Arg] = &*DI;
Dst.setAliasee(Val);
}
-bool ModuleLinker::linkGlobalValueBody(GlobalValue &Src) {
- Value *Dst = ValueMap[&Src];
- assert(Dst);
+bool ModuleLinker::linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src) {
+ if (const Comdat *SC = Src.getComdat()) {
+ // To ensure that we don't generate an incomplete comdat group,
+ // we must materialize and map in any other members that are not
+ // yet materialized in Dst, which also ensures their definitions
+ // are linked in. Otherwise, linkonce and other lazy linked GVs will
+ // not be materialized if they aren't referenced.
+ for (auto *SGV : ComdatMembers[SC]) {
+ auto *DGV = cast_or_null<GlobalValue>(ValueMap.lookup(SGV));
+ if (DGV && !DGV->isDeclaration())
+ continue;
+ MapValue(SGV, ValueMap, RF_MoveDistinctMDs, &TypeMap, &ValMaterializer);
+ }
+ }
if (shouldInternalizeLinkedSymbols())
- if (auto *DGV = dyn_cast<GlobalValue>(Dst))
+ if (auto *DGV = dyn_cast<GlobalValue>(&Dst))
DGV->setLinkage(GlobalValue::InternalLinkage);
if (auto *F = dyn_cast<Function>(&Src))
- return linkFunctionBody(cast<Function>(*Dst), *F);
+ return linkFunctionBody(cast<Function>(Dst), *F);
if (auto *GVar = dyn_cast<GlobalVariable>(&Src)) {
- linkGlobalInit(cast<GlobalVariable>(*Dst), *GVar);
+ linkGlobalInit(cast<GlobalVariable>(Dst), *GVar);
return false;
}
- linkAliasBody(cast<GlobalAlias>(*Dst), cast<GlobalAlias>(Src));
+ linkAliasBody(cast<GlobalAlias>(Dst), cast<GlobalAlias>(Src));
return false;
}
/// Insert all of the named MDNodes in Src into the Dest module.
void ModuleLinker::linkNamedMDNodes() {
- const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
- for (const NamedMDNode &NMD : SrcM->named_metadata()) {
+ const NamedMDNode *SrcModFlags = SrcM.getModuleFlagsMetadata();
+ for (const NamedMDNode &NMD : SrcM.named_metadata()) {
// Don't link module flags here. Do them separately.
if (&NMD == SrcModFlags)
continue;
- NamedMDNode *DestNMD = DstM->getOrInsertNamedMetadata(NMD.getName());
+ NamedMDNode *DestNMD = DstM.getOrInsertNamedMetadata(NMD.getName());
// Add Src elements into Dest node.
for (const MDNode *op : NMD.operands())
- DestNMD->addOperand(MapMetadata(op, ValueMap, RF_MoveDistinctMDs,
- &TypeMap, &ValMaterializer));
+ DestNMD->addOperand(MapMetadata(
+ op, ValueMap, RF_MoveDistinctMDs | RF_NullMapMissingGlobalValues,
+ &TypeMap, &ValMaterializer));
}
}
/// 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();
- if (!SrcModFlags) return false;
+ const NamedMDNode *SrcModFlags = SrcM.getModuleFlagsMetadata();
+ if (!SrcModFlags)
+ return false;
// If the destination module doesn't have module flags yet, then just copy
// over the source module's flags.
- NamedMDNode *DstModFlags = DstM->getOrInsertModuleFlagsMetadata();
+ NamedMDNode *DstModFlags = DstM.getOrInsertModuleFlagsMetadata();
if (DstModFlags->getNumOperands() == 0) {
for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
DstModFlags->addOperand(SrcModFlags->getOperand(I));
// First build a map of the existing module flags and requirements.
DenseMap<MDString *, std::pair<MDNode *, unsigned>> Flags;
- SmallSetVector<MDNode*, 16> Requirements;
+ 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));
auto replaceDstValue = [&](MDNode *New) {
Metadata *FlagOps[] = {DstOp->getOperand(0), ID, New};
- MDNode *Flag = MDNode::get(DstM->getContext(), FlagOps);
+ MDNode *Flag = MDNode::get(DstM.getContext(), FlagOps);
DstModFlags->setOperand(DstIndex, Flag);
Flags[ID].first = Flag;
};
// Perform the merge for standard behavior types.
switch (SrcBehaviorValue) {
case Module::Require:
- case Module::Override: llvm_unreachable("not possible");
+ case Module::Override:
+ llvm_unreachable("not possible");
case Module::Error: {
// Emit an error if the values differ.
if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
MDs.append(DstValue->op_begin(), DstValue->op_end());
MDs.append(SrcValue->op_begin(), SrcValue->op_end());
- replaceDstValue(MDNode::get(DstM->getContext(), MDs));
+ replaceDstValue(MDNode::get(DstM.getContext(), MDs));
break;
}
case Module::AppendUnique: {
Elts.insert(DstValue->op_begin(), DstValue->op_end());
Elts.insert(SrcValue->op_begin(), SrcValue->op_end());
- replaceDstValue(MDNode::get(DstM->getContext(),
+ replaceDstValue(MDNode::get(DstM.getContext(),
makeArrayRef(Elts.begin(), Elts.end())));
break;
}
static bool triplesMatch(const Triple &T0, const Triple &T1) {
// If vendor is apple, ignore the version number.
if (T0.getVendor() == Triple::Apple)
- return T0.getArch() == T1.getArch() &&
- T0.getSubArch() == T1.getSubArch() &&
- T0.getVendor() == T1.getVendor() &&
- T0.getOS() == T1.getOS();
+ return T0.getArch() == T1.getArch() && T0.getSubArch() == T1.getSubArch() &&
+ T0.getVendor() == T1.getVendor() && T0.getOS() == T1.getOS();
return T0 == T1;
}
// This function returns the merged triple.
-static std::string mergeTriples(const Triple &SrcTriple, const Triple &DstTriple) {
+static std::string mergeTriples(const Triple &SrcTriple,
+ const Triple &DstTriple) {
// If vendor is apple, pick the triple with the larger version number.
if (SrcTriple.getVendor() == Triple::Apple)
if (DstTriple.isOSVersionLT(SrcTriple))
return DstTriple.str();
}
-bool ModuleLinker::run() {
- assert(DstM && "Null destination module");
- assert(SrcM && "Null source module");
+bool ModuleLinker::linkIfNeeded(GlobalValue &GV) {
+ GlobalValue *DGV = getLinkedToGlobal(&GV);
+
+ if (shouldLinkOnlyNeeded() && !(DGV && DGV->isDeclaration()))
+ return false;
+
+ if (DGV && !GV.hasLocalLinkage() && !GV.hasAppendingLinkage()) {
+ auto *DGVar = dyn_cast<GlobalVariable>(DGV);
+ auto *SGVar = dyn_cast<GlobalVariable>(&GV);
+ if (DGVar && SGVar) {
+ if (DGVar->isDeclaration() && SGVar->isDeclaration() &&
+ (!DGVar->isConstant() || !SGVar->isConstant())) {
+ DGVar->setConstant(false);
+ SGVar->setConstant(false);
+ }
+ if (DGVar->hasCommonLinkage() && SGVar->hasCommonLinkage()) {
+ unsigned Align = std::max(DGVar->getAlignment(), SGVar->getAlignment());
+ SGVar->setAlignment(Align);
+ DGVar->setAlignment(Align);
+ }
+ }
+
+ GlobalValue::VisibilityTypes Visibility =
+ getMinVisibility(DGV->getVisibility(), GV.getVisibility());
+ DGV->setVisibility(Visibility);
+ GV.setVisibility(Visibility);
+
+ bool HasUnnamedAddr = GV.hasUnnamedAddr() && DGV->hasUnnamedAddr();
+ DGV->setUnnamedAddr(HasUnnamedAddr);
+ GV.setUnnamedAddr(HasUnnamedAddr);
+ }
+
+ // Don't want to append to global_ctors list, for example, when we
+ // are importing for ThinLTO, otherwise the global ctors and dtors
+ // get executed multiple times for local variables (the latter causing
+ // double frees).
+ if (GV.hasAppendingLinkage() && isPerformingImport())
+ return false;
+
+ if (isPerformingImport() && !doImportAsDefinition(&GV))
+ return false;
+ if (!DGV && !shouldOverrideFromSrc() &&
+ (GV.hasLocalLinkage() || GV.hasLinkOnceLinkage() ||
+ GV.hasAvailableExternallyLinkage()))
+ return false;
+
+ if (const Comdat *SC = GV.getComdat()) {
+ bool LinkFromSrc;
+ Comdat::SelectionKind SK;
+ std::tie(SK, LinkFromSrc) = ComdatsChosen[SC];
+ if (LinkFromSrc)
+ ValuesToLink.insert(&GV);
+ return false;
+ }
+
+ bool LinkFromSrc = true;
+ if (DGV && shouldLinkFromSource(LinkFromSrc, *DGV, GV))
+ return true;
+ if (LinkFromSrc)
+ ValuesToLink.insert(&GV);
+ return false;
+}
+
+bool ModuleLinker::run() {
// Inherit the target data from the source module if the destination module
// doesn't have one already.
- if (DstM->getDataLayout().isDefault())
- DstM->setDataLayout(SrcM->getDataLayout());
+ if (DstM.getDataLayout().isDefault())
+ DstM.setDataLayout(SrcM.getDataLayout());
- if (SrcM->getDataLayout() != DstM->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");
+ SrcM.getModuleIdentifier() + "' is '" +
+ SrcM.getDataLayoutStr() + "' whereas '" +
+ DstM.getModuleIdentifier() + "' is '" +
+ DstM.getDataLayoutStr() + "'\n");
}
// 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 (DstM.getTargetTriple().empty() && !SrcM.getTargetTriple().empty())
+ DstM.setTargetTriple(SrcM.getTargetTriple());
- Triple SrcTriple(SrcM->getTargetTriple()), DstTriple(DstM->getTargetTriple());
+ Triple SrcTriple(SrcM.getTargetTriple()), DstTriple(DstM.getTargetTriple());
- if (!SrcM->getTargetTriple().empty() && !triplesMatch(SrcTriple, DstTriple))
+ 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");
+ SrcM.getModuleIdentifier() + "' is '" + SrcM.getTargetTriple() +
+ "' whereas '" + DstM.getModuleIdentifier() + "' is '" +
+ DstM.getTargetTriple() + "'\n");
- DstM->setTargetTriple(mergeTriples(SrcTriple, DstTriple));
+ DstM.setTargetTriple(mergeTriples(SrcTriple, DstTriple));
// Append the module inline asm string.
- if (!SrcM->getModuleInlineAsm().empty()) {
- if (DstM->getModuleInlineAsm().empty())
- DstM->setModuleInlineAsm(SrcM->getModuleInlineAsm());
+ if (!SrcM.getModuleInlineAsm().empty()) {
+ if (DstM.getModuleInlineAsm().empty())
+ DstM.setModuleInlineAsm(SrcM.getModuleInlineAsm());
else
- DstM->setModuleInlineAsm(DstM->getModuleInlineAsm()+"\n"+
- SrcM->getModuleInlineAsm());
+ DstM.setModuleInlineAsm(DstM.getModuleInlineAsm() + "\n" +
+ SrcM.getModuleInlineAsm());
}
// Loop over all of the linked values to compute type mappings.
computeTypeMapping();
ComdatsChosen.clear();
- for (const auto &SMEC : SrcM->getComdatSymbolTable()) {
+ for (const auto &SMEC : SrcM.getComdatSymbolTable()) {
const Comdat &C = SMEC.getValue();
if (ComdatsChosen.count(&C))
continue;
// Upgrade mismatched global arrays.
upgradeMismatchedGlobals();
+ for (GlobalVariable &GV : SrcM.globals())
+ if (const Comdat *SC = GV.getComdat())
+ ComdatMembers[SC].push_back(&GV);
+
+ for (Function &SF : SrcM)
+ if (const Comdat *SC = SF.getComdat())
+ ComdatMembers[SC].push_back(&SF);
+
+ for (GlobalAlias &GA : SrcM.aliases())
+ if (const Comdat *SC = GA.getComdat())
+ ComdatMembers[SC].push_back(&GA);
+
// Insert all of the globals in src into the DstM module... without linking
// initializers (which could refer to functions not yet mapped over).
- for (GlobalVariable &GV : SrcM->globals())
- if (linkGlobalValueProto(&GV))
+ for (GlobalVariable &GV : SrcM.globals())
+ if (linkIfNeeded(GV))
return true;
- // Link the functions together between the two modules, without doing function
- // bodies... this just adds external function prototypes to the DstM
- // function... We do this so that when we begin processing function bodies,
- // all of the global values that may be referenced are available in our
- // ValueMap.
- for (Function &F :*SrcM)
- if (linkGlobalValueProto(&F))
+ for (Function &SF : SrcM)
+ if (linkIfNeeded(SF))
return true;
- // If there were any aliases, link them now.
- for (GlobalAlias &GA : SrcM->aliases())
- if (linkGlobalValueProto(&GA))
- return true;
-
- for (const AppendingVarInfo &AppendingVar : AppendingVars)
- linkAppendingVarInit(AppendingVar);
-
- for (const auto &Entry : DstM->getComdatSymbolTable()) {
- const Comdat &C = Entry.getValue();
- if (C.getSelectionKind() == Comdat::Any)
- continue;
- const GlobalValue *GV = SrcM->getNamedValue(C.getName());
- if (GV)
- MapValue(GV, ValueMap, RF_MoveDistinctMDs, &TypeMap, &ValMaterializer);
- }
-
- // Link in the function bodies that are defined in the source module into
- // DstM.
- for (Function &SF : *SrcM) {
- // Skip if no body (function is external).
- if (SF.isDeclaration())
- continue;
-
- // Skip if not linking from source.
- if (DoNotLinkFromSource.count(&SF))
- continue;
-
- // When importing, only materialize the function requested for import.
- if (isPerformingImport() && &SF != ImportFunction)
- continue;
-
- if (linkGlobalValueBody(SF))
+ for (GlobalAlias &GA : SrcM.aliases())
+ if (linkIfNeeded(GA))
return true;
- }
-
- // Resolve all uses of aliases with aliasees.
- for (GlobalAlias &Src : SrcM->aliases()) {
- if (DoNotLinkFromSource.count(&Src))
- continue;
- linkGlobalValueBody(Src);
- }
-
- // Update the initializers in the DstM module now that all globals that may
- // be referenced are in DstM.
- for (GlobalVariable &Src : SrcM->globals()) {
- // Only process initialized GV's or ones not already in dest.
- if (!Src.hasInitializer() || DoNotLinkFromSource.count(&Src))
- continue;
- linkGlobalValueBody(Src);
- }
-
- // Process vector of lazily linked in functions.
- while (!LazilyLinkGlobalValues.empty()) {
- GlobalValue *SGV = LazilyLinkGlobalValues.back();
- LazilyLinkGlobalValues.pop_back();
- if (isPerformingImport() && !doImportAsDefinition(SGV))
- continue;
-
- // Skip declarations that ValueMaterializer may have created in
- // case we link in only some of SrcM.
- if (shouldLinkOnlyNeeded() && SGV->isDeclaration())
- continue;
- assert(!SGV->isDeclaration() && "users should not pass down decls");
- if (linkGlobalValueBody(*SGV))
+ for (GlobalValue *GV : ValuesToLink) {
+ MapValue(GV, ValueMap, RF_MoveDistinctMDs, &TypeMap, &ValMaterializer);
+ if (HasError)
return true;
}
return *I == Ty;
}
-void Linker::init(Module *M, DiagnosticHandlerFunction DiagnosticHandler) {
- this->Composite = M;
- this->DiagnosticHandler = DiagnosticHandler;
-
+Linker::Linker(Module &M, DiagnosticHandlerFunction DiagnosticHandler)
+ : Composite(M), DiagnosticHandler(DiagnosticHandler) {
TypeFinder StructTypes;
- StructTypes.run(*M, true);
+ StructTypes.run(M, true);
for (StructType *Ty : StructTypes) {
if (Ty->isOpaque())
IdentifiedStructTypes.addOpaque(Ty);
}
}
-Linker::Linker(Module *M, DiagnosticHandlerFunction DiagnosticHandler) {
- init(M, DiagnosticHandler);
-}
-
-Linker::Linker(Module *M) {
- init(M, [this](const DiagnosticInfo &DI) {
- Composite->getContext().diagnose(DI);
- });
-}
-
-void Linker::deleteModule() {
- delete Composite;
- Composite = nullptr;
-}
-
-bool Linker::linkInModule(Module *Src, unsigned Flags, FunctionInfoIndex *Index,
- Function *FuncToImport) {
+bool Linker::linkInModule(Module &Src, unsigned Flags,
+ const FunctionInfoIndex *Index,
+ DenseSet<const GlobalValue *> *FunctionsToImport) {
ModuleLinker TheLinker(Composite, IdentifiedStructTypes, Src,
- DiagnosticHandler, Flags, Index, FuncToImport);
+ DiagnosticHandler, Flags, Index, FunctionsToImport);
bool RetCode = TheLinker.run();
- Composite->dropTriviallyDeadConstantArrays();
+ Composite.dropTriviallyDeadConstantArrays();
return RetCode;
}
-void Linker::setModule(Module *Dst) {
- init(Dst, DiagnosticHandler);
-}
-
//===----------------------------------------------------------------------===//
// LinkModules entrypoint.
//===----------------------------------------------------------------------===//
/// 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,
+bool Linker::linkModules(Module &Dest, Module &Src,
DiagnosticHandlerFunction DiagnosticHandler,
unsigned Flags) {
Linker L(Dest, DiagnosticHandler);
return L.linkInModule(Src, Flags);
}
-bool Linker::LinkModules(Module *Dest, Module *Src, unsigned Flags) {
- Linker L(Dest);
- return L.linkInModule(Src, Flags);
-}
-
//===----------------------------------------------------------------------===//
// C API.
//===----------------------------------------------------------------------===//
raw_string_ostream Stream(Message);
DiagnosticPrinterRawOStream DP(Stream);
- LLVMBool Result = Linker::LinkModules(
- D, unwrap(Src), [&](const DiagnosticInfo &DI) { DI.print(DP); });
+ LLVMBool Result = Linker::linkModules(
+ *D, *unwrap(Src), [&](const DiagnosticInfo &DI) { DI.print(DP); });
if (OutMessages && Result) {
Stream.flush();