1494 lines
55 KiB
C++
1494 lines
55 KiB
C++
//===- lib/Linker/IRMover.cpp ---------------------------------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/Linker/IRMover.h"
|
|
#include "LinkDiagnosticInfo.h"
|
|
#include "llvm/ADT/SetVector.h"
|
|
#include "llvm/ADT/SmallString.h"
|
|
#include "llvm/ADT/Triple.h"
|
|
#include "llvm/IR/Constants.h"
|
|
#include "llvm/IR/DebugInfo.h"
|
|
#include "llvm/IR/DiagnosticPrinter.h"
|
|
#include "llvm/IR/GVMaterializer.h"
|
|
#include "llvm/IR/Intrinsics.h"
|
|
#include "llvm/IR/TypeFinder.h"
|
|
#include "llvm/Support/Error.h"
|
|
#include "llvm/Transforms/Utils/Cloning.h"
|
|
#include <utility>
|
|
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;
|
|
|
|
/// 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<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;
|
|
|
|
/// 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(IRMover::IdentifiedStructTypeSet &DstStructTypesSet)
|
|
: DstStructTypesSet(DstStructTypesSet) {}
|
|
|
|
IRMover::IdentifiedStructTypeSet &DstStructTypesSet;
|
|
/// 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);
|
|
|
|
/// Produce a body for an opaque type in the dest module from a type
|
|
/// definition in the source module.
|
|
void linkDefinedTypeBodies();
|
|
|
|
/// Return the mapped type to use for the specified input type from the
|
|
/// source module.
|
|
Type *get(Type *SrcTy);
|
|
Type *get(Type *SrcTy, SmallPtrSet<StructType *, 8> &Visited);
|
|
|
|
void finishType(StructType *DTy, StructType *STy, ArrayRef<Type *> ETypes);
|
|
|
|
FunctionType *get(FunctionType *T) {
|
|
return cast<FunctionType>(get((Type *)T));
|
|
}
|
|
|
|
private:
|
|
Type *remapType(Type *SrcTy) override { return get(SrcTy); }
|
|
|
|
bool areTypesIsomorphic(Type *DstTy, Type *SrcTy);
|
|
};
|
|
}
|
|
|
|
void TypeMapTy::addTypeMapping(Type *DstTy, Type *SrcTy) {
|
|
assert(SpeculativeTypes.empty());
|
|
assert(SpeculativeDstOpaqueTypes.empty());
|
|
|
|
// Check to see if these types are recursively isomorphic and establish a
|
|
// mapping between them if so.
|
|
if (!areTypesIsomorphic(DstTy, SrcTy)) {
|
|
// Oops, they aren't isomorphic. Just discard this request by rolling out
|
|
// any speculative mappings we've established.
|
|
for (Type *Ty : SpeculativeTypes)
|
|
MappedTypes.erase(Ty);
|
|
|
|
SrcDefinitionsToResolve.resize(SrcDefinitionsToResolve.size() -
|
|
SpeculativeDstOpaqueTypes.size());
|
|
for (StructType *Ty : SpeculativeDstOpaqueTypes)
|
|
DstResolvedOpaqueTypes.erase(Ty);
|
|
} else {
|
|
// SrcTy and DstTy are recursively ismorphic. We clear names of SrcTy
|
|
// and all its descendants to lower amount of renaming in LLVM context
|
|
// Renaming occurs because we load all source modules to the same context
|
|
// and declaration with existing name gets renamed (i.e Foo -> Foo.42).
|
|
// As a result we may get several different types in the destination
|
|
// module, which are in fact the same.
|
|
for (Type *Ty : SpeculativeTypes)
|
|
if (auto *STy = dyn_cast<StructType>(Ty))
|
|
if (STy->hasName())
|
|
STy->setName("");
|
|
}
|
|
SpeculativeTypes.clear();
|
|
SpeculativeDstOpaqueTypes.clear();
|
|
}
|
|
|
|
/// 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;
|
|
|
|
// If we have an entry in the MappedTypes table, then we have our answer.
|
|
Type *&Entry = MappedTypes[SrcTy];
|
|
if (Entry)
|
|
return Entry == DstTy;
|
|
|
|
// Two identical types are clearly isomorphic. Remember this
|
|
// non-speculatively.
|
|
if (DstTy == SrcTy) {
|
|
Entry = DstTy;
|
|
return true;
|
|
}
|
|
|
|
// Okay, we have two types with identical kinds that we haven't seen before.
|
|
|
|
// If this is an opaque struct type, special case it.
|
|
if (StructType *SSTy = dyn_cast<StructType>(SrcTy)) {
|
|
// Mapping an opaque type to any struct, just keep the dest struct.
|
|
if (SSTy->isOpaque()) {
|
|
Entry = DstTy;
|
|
SpeculativeTypes.push_back(SrcTy);
|
|
return true;
|
|
}
|
|
|
|
// Mapping a non-opaque source type to an opaque dest. If this is the first
|
|
// type that we're mapping onto this destination type then we succeed. Keep
|
|
// the dest, but fill it in later. If this is the second (different) type
|
|
// that we're trying to map onto the 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)).second)
|
|
return false;
|
|
SrcDefinitionsToResolve.push_back(SSTy);
|
|
SpeculativeTypes.push_back(SrcTy);
|
|
SpeculativeDstOpaqueTypes.push_back(cast<StructType>(DstTy));
|
|
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;
|
|
} else if (StructType *DSTy = dyn_cast<StructType>(DstTy)) {
|
|
StructType *SSTy = cast<StructType>(SrcTy);
|
|
if (DSTy->isLiteral() != SSTy->isLiteral() ||
|
|
DSTy->isPacked() != SSTy->isPacked())
|
|
return false;
|
|
} else if (auto *DSeqTy = dyn_cast<SequentialType>(DstTy)) {
|
|
if (DSeqTy->getNumElements() !=
|
|
cast<SequentialType>(SrcTy)->getNumElements())
|
|
return false;
|
|
}
|
|
|
|
// Otherwise, we speculate that these two types will line up and recursively
|
|
// check the subelements.
|
|
Entry = DstTy;
|
|
SpeculativeTypes.push_back(SrcTy);
|
|
|
|
for (unsigned I = 0, E = SrcTy->getNumContainedTypes(); I != E; ++I)
|
|
if (!areTypesIsomorphic(DstTy->getContainedType(I),
|
|
SrcTy->getContainedType(I)))
|
|
return false;
|
|
|
|
// If everything seems to have lined up, then everything is great.
|
|
return true;
|
|
}
|
|
|
|
void TypeMapTy::linkDefinedTypeBodies() {
|
|
SmallVector<Type *, 16> Elements;
|
|
for (StructType *SrcSTy : SrcDefinitionsToResolve) {
|
|
StructType *DstSTy = cast<StructType>(MappedTypes[SrcSTy]);
|
|
assert(DstSTy->isOpaque());
|
|
|
|
// 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] = get(SrcSTy->getElementType(I));
|
|
|
|
DstSTy->setBody(Elements, SrcSTy->isPacked());
|
|
DstStructTypesSet.switchToNonOpaque(DstSTy);
|
|
}
|
|
SrcDefinitionsToResolve.clear();
|
|
DstResolvedOpaqueTypes.clear();
|
|
}
|
|
|
|
void TypeMapTy::finishType(StructType *DTy, StructType *STy,
|
|
ArrayRef<Type *> ETypes) {
|
|
DTy->setBody(ETypes, STy->isPacked());
|
|
|
|
// Steal STy's name.
|
|
if (STy->hasName()) {
|
|
SmallString<16> TmpName = STy->getName();
|
|
STy->setName("");
|
|
DTy->setName(TmpName);
|
|
}
|
|
|
|
DstStructTypesSet.addNonOpaque(DTy);
|
|
}
|
|
|
|
Type *TypeMapTy::get(Type *Ty) {
|
|
SmallPtrSet<StructType *, 8> Visited;
|
|
return get(Ty, Visited);
|
|
}
|
|
|
|
Type *TypeMapTy::get(Type *Ty, SmallPtrSet<StructType *, 8> &Visited) {
|
|
// If we already have an entry for this type, return it.
|
|
Type **Entry = &MappedTypes[Ty];
|
|
if (*Entry)
|
|
return *Entry;
|
|
|
|
// These are types that LLVM itself will unique.
|
|
bool IsUniqued = !isa<StructType>(Ty) || cast<StructType>(Ty)->isLiteral();
|
|
|
|
if (!IsUniqued) {
|
|
StructType *STy = cast<StructType>(Ty);
|
|
// This is actually a type from the destination module, this can be reached
|
|
// when this type is loaded in another module, added to DstStructTypesSet,
|
|
// and then we reach the same type in another module where it has not been
|
|
// added to MappedTypes. (PR37684)
|
|
if (STy->getContext().isODRUniquingDebugTypes() && !STy->isOpaque() &&
|
|
DstStructTypesSet.hasType(STy))
|
|
return *Entry = STy;
|
|
|
|
#ifndef NDEBUG
|
|
for (auto &Pair : MappedTypes) {
|
|
assert(!(Pair.first != Ty && Pair.second == Ty) &&
|
|
"mapping to a source type");
|
|
}
|
|
#endif
|
|
|
|
if (!Visited.insert(STy).second) {
|
|
StructType *DTy = StructType::create(Ty->getContext());
|
|
return *Entry = DTy;
|
|
}
|
|
}
|
|
|
|
// If this is not a recursive type, then just map all of the elements and
|
|
// then rebuild the type from inside out.
|
|
SmallVector<Type *, 4> ElementTypes;
|
|
|
|
// If there are no element types to map, then the type is itself. This is
|
|
// true for the anonymous {} struct, things like 'float', integers, etc.
|
|
if (Ty->getNumContainedTypes() == 0 && IsUniqued)
|
|
return *Entry = Ty;
|
|
|
|
// Remap all of the elements, keeping track of whether any of them change.
|
|
bool AnyChange = false;
|
|
ElementTypes.resize(Ty->getNumContainedTypes());
|
|
for (unsigned I = 0, E = Ty->getNumContainedTypes(); I != E; ++I) {
|
|
ElementTypes[I] = get(Ty->getContainedType(I), Visited);
|
|
AnyChange |= ElementTypes[I] != Ty->getContainedType(I);
|
|
}
|
|
|
|
// If we found our type while recursively processing stuff, just use it.
|
|
Entry = &MappedTypes[Ty];
|
|
if (*Entry) {
|
|
if (auto *DTy = dyn_cast<StructType>(*Entry)) {
|
|
if (DTy->isOpaque()) {
|
|
auto *STy = cast<StructType>(Ty);
|
|
finishType(DTy, STy, ElementTypes);
|
|
}
|
|
}
|
|
return *Entry;
|
|
}
|
|
|
|
// If all of the element types mapped directly over and the type is not
|
|
// a named struct, then the type is usable as-is.
|
|
if (!AnyChange && IsUniqued)
|
|
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:
|
|
return *Entry = VectorType::get(ElementTypes[0],
|
|
cast<VectorType>(Ty)->getNumElements());
|
|
case Type::PointerTyID:
|
|
return *Entry = PointerType::get(ElementTypes[0],
|
|
cast<PointerType>(Ty)->getAddressSpace());
|
|
case Type::FunctionTyID:
|
|
return *Entry = FunctionType::get(ElementTypes[0],
|
|
makeArrayRef(ElementTypes).slice(1),
|
|
cast<FunctionType>(Ty)->isVarArg());
|
|
case Type::StructTyID: {
|
|
auto *STy = cast<StructType>(Ty);
|
|
bool IsPacked = STy->isPacked();
|
|
if (IsUniqued)
|
|
return *Entry = StructType::get(Ty->getContext(), ElementTypes, IsPacked);
|
|
|
|
// If the type is opaque, we can just use it directly.
|
|
if (STy->isOpaque()) {
|
|
DstStructTypesSet.addOpaque(STy);
|
|
return *Entry = Ty;
|
|
}
|
|
|
|
if (StructType *OldT =
|
|
DstStructTypesSet.findNonOpaque(ElementTypes, IsPacked)) {
|
|
STy->setName("");
|
|
return *Entry = OldT;
|
|
}
|
|
|
|
if (!AnyChange) {
|
|
DstStructTypesSet.addNonOpaque(STy);
|
|
return *Entry = Ty;
|
|
}
|
|
|
|
StructType *DTy = StructType::create(Ty->getContext());
|
|
finishType(DTy, STy, ElementTypes);
|
|
return *Entry = DTy;
|
|
}
|
|
}
|
|
}
|
|
|
|
LinkDiagnosticInfo::LinkDiagnosticInfo(DiagnosticSeverity Severity,
|
|
const Twine &Msg)
|
|
: DiagnosticInfo(DK_Linker, Severity), Msg(Msg) {}
|
|
void LinkDiagnosticInfo::print(DiagnosticPrinter &DP) const { DP << Msg; }
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// IRLinker implementation.
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
namespace {
|
|
class IRLinker;
|
|
|
|
/// 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 GlobalValueMaterializer final : public ValueMaterializer {
|
|
IRLinker &TheIRLinker;
|
|
|
|
public:
|
|
GlobalValueMaterializer(IRLinker &TheIRLinker) : TheIRLinker(TheIRLinker) {}
|
|
Value *materialize(Value *V) override;
|
|
};
|
|
|
|
class LocalValueMaterializer final : public ValueMaterializer {
|
|
IRLinker &TheIRLinker;
|
|
|
|
public:
|
|
LocalValueMaterializer(IRLinker &TheIRLinker) : TheIRLinker(TheIRLinker) {}
|
|
Value *materialize(Value *V) override;
|
|
};
|
|
|
|
/// Type of the Metadata map in \a ValueToValueMapTy.
|
|
typedef DenseMap<const Metadata *, TrackingMDRef> MDMapT;
|
|
|
|
/// This is responsible for keeping track of the state used for moving data
|
|
/// from SrcM to DstM.
|
|
class IRLinker {
|
|
Module &DstM;
|
|
std::unique_ptr<Module> SrcM;
|
|
|
|
/// See IRMover::move().
|
|
std::function<void(GlobalValue &, IRMover::ValueAdder)> AddLazyFor;
|
|
|
|
TypeMapTy TypeMap;
|
|
GlobalValueMaterializer GValMaterializer;
|
|
LocalValueMaterializer LValMaterializer;
|
|
|
|
/// A metadata map that's shared between IRLinker instances.
|
|
MDMapT &SharedMDs;
|
|
|
|
/// 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;
|
|
ValueToValueMapTy AliasValueMap;
|
|
|
|
DenseSet<GlobalValue *> ValuesToLink;
|
|
std::vector<GlobalValue *> Worklist;
|
|
|
|
void maybeAdd(GlobalValue *GV) {
|
|
if (ValuesToLink.insert(GV).second)
|
|
Worklist.push_back(GV);
|
|
}
|
|
|
|
/// Whether we are importing globals for ThinLTO, as opposed to linking the
|
|
/// source module. If this flag is set, it means that we can rely on some
|
|
/// other object file to define any non-GlobalValue entities defined by the
|
|
/// source module. This currently causes us to not link retained types in
|
|
/// debug info metadata and module inline asm.
|
|
bool IsPerformingImport;
|
|
|
|
/// 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 = false;
|
|
|
|
/// The Error encountered during materialization. We use an Optional here to
|
|
/// avoid needing to manage an unconsumed success value.
|
|
Optional<Error> FoundError;
|
|
void setError(Error E) {
|
|
if (E)
|
|
FoundError = std::move(E);
|
|
}
|
|
|
|
/// Most of the errors produced by this module are inconvertible StringErrors.
|
|
/// This convenience function lets us return one of those more easily.
|
|
Error stringErr(const Twine &T) {
|
|
return make_error<StringError>(T, inconvertibleErrorCode());
|
|
}
|
|
|
|
/// Entry point for mapping values and alternate context for mapping aliases.
|
|
ValueMapper Mapper;
|
|
unsigned AliasMCID;
|
|
|
|
/// Handles cloning of a global values from the source module into
|
|
/// the destination module, including setting the attributes and visibility.
|
|
GlobalValue *copyGlobalValueProto(const GlobalValue *SGV, bool ForDefinition);
|
|
|
|
void emitWarning(const Twine &Message) {
|
|
SrcM->getContext().diagnose(LinkDiagnosticInfo(DS_Warning, Message));
|
|
}
|
|
|
|
/// 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 nullptr;
|
|
|
|
// Otherwise see if we have a match in the destination module's symtab.
|
|
GlobalValue *DGV = DstM.getNamedValue(SrcGV->getName());
|
|
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 nullptr;
|
|
|
|
// Otherwise, we do in fact link to the destination global.
|
|
return DGV;
|
|
}
|
|
|
|
void computeTypeMapping();
|
|
|
|
Expected<Constant *> linkAppendingVarProto(GlobalVariable *DstGV,
|
|
const GlobalVariable *SrcGV);
|
|
|
|
/// Given the GlobaValue \p SGV in the source module, and the matching
|
|
/// GlobalValue \p DGV (if any), return true if the linker will pull \p SGV
|
|
/// into the destination module.
|
|
///
|
|
/// Note this code may call the client-provided \p AddLazyFor.
|
|
bool shouldLink(GlobalValue *DGV, GlobalValue &SGV);
|
|
Expected<Constant *> linkGlobalValueProto(GlobalValue *GV, bool ForAlias);
|
|
|
|
Error linkModuleFlagsMetadata();
|
|
|
|
void linkGlobalVariable(GlobalVariable &Dst, GlobalVariable &Src);
|
|
Error linkFunctionBody(Function &Dst, Function &Src);
|
|
void linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src);
|
|
Error linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src);
|
|
|
|
/// Functions that take care of cloning a specific global value type
|
|
/// into the destination module.
|
|
GlobalVariable *copyGlobalVariableProto(const GlobalVariable *SGVar);
|
|
Function *copyFunctionProto(const Function *SF);
|
|
GlobalValue *copyGlobalAliasProto(const GlobalAlias *SGA);
|
|
|
|
/// When importing for ThinLTO, prevent importing of types listed on
|
|
/// the DICompileUnit that we don't need a copy of in the importing
|
|
/// module.
|
|
void prepareCompileUnitsForImport();
|
|
void linkNamedMDNodes();
|
|
|
|
public:
|
|
IRLinker(Module &DstM, MDMapT &SharedMDs,
|
|
IRMover::IdentifiedStructTypeSet &Set, std::unique_ptr<Module> SrcM,
|
|
ArrayRef<GlobalValue *> ValuesToLink,
|
|
std::function<void(GlobalValue &, IRMover::ValueAdder)> AddLazyFor,
|
|
bool IsPerformingImport)
|
|
: DstM(DstM), SrcM(std::move(SrcM)), AddLazyFor(std::move(AddLazyFor)),
|
|
TypeMap(Set), GValMaterializer(*this), LValMaterializer(*this),
|
|
SharedMDs(SharedMDs), IsPerformingImport(IsPerformingImport),
|
|
Mapper(ValueMap, RF_MoveDistinctMDs | RF_IgnoreMissingLocals, &TypeMap,
|
|
&GValMaterializer),
|
|
AliasMCID(Mapper.registerAlternateMappingContext(AliasValueMap,
|
|
&LValMaterializer)) {
|
|
ValueMap.getMDMap() = std::move(SharedMDs);
|
|
for (GlobalValue *GV : ValuesToLink)
|
|
maybeAdd(GV);
|
|
if (IsPerformingImport)
|
|
prepareCompileUnitsForImport();
|
|
}
|
|
~IRLinker() { SharedMDs = std::move(*ValueMap.getMDMap()); }
|
|
|
|
Error run();
|
|
Value *materialize(Value *V, bool ForAlias);
|
|
};
|
|
}
|
|
|
|
/// 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.
|
|
if (GV->hasLocalLinkage() || GV->getName() == Name)
|
|
return;
|
|
|
|
Module *M = GV->getParent();
|
|
|
|
// 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
|
|
assert(ConflictGV->getName() != Name && "forceRenaming didn't work");
|
|
} else {
|
|
GV->setName(Name); // Force the name back
|
|
}
|
|
}
|
|
|
|
Value *GlobalValueMaterializer::materialize(Value *SGV) {
|
|
return TheIRLinker.materialize(SGV, false);
|
|
}
|
|
|
|
Value *LocalValueMaterializer::materialize(Value *SGV) {
|
|
return TheIRLinker.materialize(SGV, true);
|
|
}
|
|
|
|
Value *IRLinker::materialize(Value *V, bool ForAlias) {
|
|
auto *SGV = dyn_cast<GlobalValue>(V);
|
|
if (!SGV)
|
|
return nullptr;
|
|
|
|
Expected<Constant *> NewProto = linkGlobalValueProto(SGV, ForAlias);
|
|
if (!NewProto) {
|
|
setError(NewProto.takeError());
|
|
return nullptr;
|
|
}
|
|
if (!*NewProto)
|
|
return nullptr;
|
|
|
|
GlobalValue *New = dyn_cast<GlobalValue>(*NewProto);
|
|
if (!New)
|
|
return *NewProto;
|
|
|
|
// If we already created the body, just return.
|
|
if (auto *F = dyn_cast<Function>(New)) {
|
|
if (!F->isDeclaration())
|
|
return New;
|
|
} else if (auto *V = dyn_cast<GlobalVariable>(New)) {
|
|
if (V->hasInitializer() || V->hasAppendingLinkage())
|
|
return New;
|
|
} else {
|
|
auto *A = cast<GlobalAlias>(New);
|
|
if (A->getAliasee())
|
|
return New;
|
|
}
|
|
|
|
// When linking a global for an alias, it will always be linked. However we
|
|
// need to check if it was not already scheduled to satisfy a reference from a
|
|
// regular global value initializer. We know if it has been schedule if the
|
|
// "New" GlobalValue that is mapped here for the alias is the same as the one
|
|
// already mapped. If there is an entry in the ValueMap but the value is
|
|
// different, it means that the value already had a definition in the
|
|
// destination module (linkonce for instance), but we need a new definition
|
|
// for the alias ("New" will be different.
|
|
if (ForAlias && ValueMap.lookup(SGV) == New)
|
|
return New;
|
|
|
|
if (ForAlias || shouldLink(New, *SGV))
|
|
setError(linkGlobalValueBody(*New, *SGV));
|
|
|
|
return New;
|
|
}
|
|
|
|
/// Loop through the global variables in the src module and merge them into the
|
|
/// dest module.
|
|
GlobalVariable *IRLinker::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->getValueType()),
|
|
SGVar->isConstant(), GlobalValue::ExternalLinkage,
|
|
/*init*/ nullptr, SGVar->getName(),
|
|
/*insertbefore*/ nullptr, SGVar->getThreadLocalMode(),
|
|
SGVar->getType()->getAddressSpace());
|
|
NewDGV->setAlignment(SGVar->getAlignment());
|
|
NewDGV->copyAttributesFrom(SGVar);
|
|
return NewDGV;
|
|
}
|
|
|
|
/// Link the function in the source module into the destination module if
|
|
/// needed, setting up mapping information.
|
|
Function *IRLinker::copyFunctionProto(const Function *SF) {
|
|
// If there is no linkage to be performed or we are linking from the source,
|
|
// bring SF over.
|
|
auto *F =
|
|
Function::Create(TypeMap.get(SF->getFunctionType()),
|
|
GlobalValue::ExternalLinkage, SF->getName(), &DstM);
|
|
F->copyAttributesFrom(SF);
|
|
return F;
|
|
}
|
|
|
|
/// Set up prototypes for any aliases that come over from the source module.
|
|
GlobalValue *IRLinker::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());
|
|
auto *GA =
|
|
GlobalAlias::create(Ty, SGA->getType()->getPointerAddressSpace(),
|
|
GlobalValue::ExternalLinkage, SGA->getName(), &DstM);
|
|
GA->copyAttributesFrom(SGA);
|
|
return GA;
|
|
}
|
|
|
|
GlobalValue *IRLinker::copyGlobalValueProto(const GlobalValue *SGV,
|
|
bool ForDefinition) {
|
|
GlobalValue *NewGV;
|
|
if (auto *SGVar = dyn_cast<GlobalVariable>(SGV)) {
|
|
NewGV = copyGlobalVariableProto(SGVar);
|
|
} else if (auto *SF = dyn_cast<Function>(SGV)) {
|
|
NewGV = copyFunctionProto(SF);
|
|
} else {
|
|
if (ForDefinition)
|
|
NewGV = copyGlobalAliasProto(cast<GlobalAlias>(SGV));
|
|
else if (SGV->getValueType()->isFunctionTy())
|
|
NewGV =
|
|
Function::Create(cast<FunctionType>(TypeMap.get(SGV->getValueType())),
|
|
GlobalValue::ExternalLinkage, SGV->getName(), &DstM);
|
|
else
|
|
NewGV = new GlobalVariable(
|
|
DstM, TypeMap.get(SGV->getValueType()),
|
|
/*isConstant*/ false, GlobalValue::ExternalLinkage,
|
|
/*init*/ nullptr, SGV->getName(),
|
|
/*insertbefore*/ nullptr, SGV->getThreadLocalMode(),
|
|
SGV->getType()->getAddressSpace());
|
|
}
|
|
|
|
if (ForDefinition)
|
|
NewGV->setLinkage(SGV->getLinkage());
|
|
else if (SGV->hasExternalWeakLinkage())
|
|
NewGV->setLinkage(GlobalValue::ExternalWeakLinkage);
|
|
|
|
if (auto *NewGO = dyn_cast<GlobalObject>(NewGV)) {
|
|
// Metadata for global variables and function declarations is copied eagerly.
|
|
if (isa<GlobalVariable>(SGV) || SGV->isDeclaration())
|
|
NewGO->copyMetadata(cast<GlobalObject>(SGV), 0);
|
|
}
|
|
|
|
// Remove these copied constants in case this stays a declaration, since
|
|
// they point to the source module. If the def is linked the values will
|
|
// be mapped in during linkFunctionBody.
|
|
if (auto *NewF = dyn_cast<Function>(NewGV)) {
|
|
NewF->setPersonalityFn(nullptr);
|
|
NewF->setPrefixData(nullptr);
|
|
NewF->setPrologueData(nullptr);
|
|
}
|
|
|
|
return NewGV;
|
|
}
|
|
|
|
static StringRef getTypeNamePrefix(StringRef Name) {
|
|
size_t DotPos = Name.rfind('.');
|
|
return (DotPos == 0 || DotPos == StringRef::npos || Name.back() == '.' ||
|
|
!isdigit(static_cast<unsigned char>(Name[DotPos + 1])))
|
|
? Name
|
|
: Name.substr(0, DotPos);
|
|
}
|
|
|
|
/// 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 IRLinker::computeTypeMapping() {
|
|
for (GlobalValue &SGV : SrcM->globals()) {
|
|
GlobalValue *DGV = getLinkedToGlobal(&SGV);
|
|
if (!DGV)
|
|
continue;
|
|
|
|
if (!DGV->hasAppendingLinkage() || !SGV.hasAppendingLinkage()) {
|
|
TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
|
|
continue;
|
|
}
|
|
|
|
// Unify the element type of appending arrays.
|
|
ArrayType *DAT = cast<ArrayType>(DGV->getValueType());
|
|
ArrayType *SAT = cast<ArrayType>(SGV.getValueType());
|
|
TypeMap.addTypeMapping(DAT->getElementType(), SAT->getElementType());
|
|
}
|
|
|
|
for (GlobalValue &SGV : *SrcM)
|
|
if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
|
|
TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
|
|
|
|
for (GlobalValue &SGV : SrcM->aliases())
|
|
if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
|
|
TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
|
|
|
|
// Incorporate types by name, scanning all the types in the source module.
|
|
// 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();
|
|
for (StructType *ST : Types) {
|
|
if (!ST->hasName())
|
|
continue;
|
|
|
|
if (TypeMap.DstStructTypesSet.hasType(ST)) {
|
|
// This is actually a type from the destination module.
|
|
// getIdentifiedStructTypes() can have found it by walking debug info
|
|
// metadata nodes, some of which get linked by name when ODR Type Uniquing
|
|
// is enabled on the Context, from the source to the destination module.
|
|
continue;
|
|
}
|
|
|
|
auto STTypePrefix = getTypeNamePrefix(ST->getName());
|
|
if (STTypePrefix.size()== ST->getName().size())
|
|
continue;
|
|
|
|
// Check to see if the destination module has a struct with the prefix name.
|
|
StructType *DST = DstM.getTypeByName(STTypePrefix);
|
|
if (!DST)
|
|
continue;
|
|
|
|
// Don't use it if this actually came from the source module. They're in
|
|
// the same LLVMContext after all. Also don't use it unless the type is
|
|
// actually used in the destination module. This can happen in situations
|
|
// like this:
|
|
//
|
|
// Module A Module B
|
|
// -------- --------
|
|
// %Z = type { %A } %B = type { %C.1 }
|
|
// %A = type { %B.1, [7 x i8] } %C.1 = type { i8* }
|
|
// %B.1 = type { %C } %A.2 = type { %B.3, [5 x i8] }
|
|
// %C = type { i8* } %B.3 = type { %C.1 }
|
|
//
|
|
// When we link Module B with Module A, the '%B' in Module B is
|
|
// used. However, that would then use '%C.1'. But when we process '%C.1',
|
|
// we prefer to take the '%C' version. So we are then left with both
|
|
// '%C.1' and '%C' being used for the same types. This leads to some
|
|
// variables using one type and some using the other.
|
|
if (TypeMap.DstStructTypesSet.hasType(DST))
|
|
TypeMap.addTypeMapping(DST, ST);
|
|
}
|
|
|
|
// 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.
|
|
TypeMap.linkDefinedTypeBodies();
|
|
}
|
|
|
|
static void getArrayElements(const Constant *C,
|
|
SmallVectorImpl<Constant *> &Dest) {
|
|
unsigned NumElements = cast<ArrayType>(C->getType())->getNumElements();
|
|
|
|
for (unsigned i = 0; i != NumElements; ++i)
|
|
Dest.push_back(C->getAggregateElement(i));
|
|
}
|
|
|
|
/// If there were any appending global variables, link them together now.
|
|
Expected<Constant *>
|
|
IRLinker::linkAppendingVarProto(GlobalVariable *DstGV,
|
|
const GlobalVariable *SrcGV) {
|
|
Type *EltTy = cast<ArrayType>(TypeMap.get(SrcGV->getValueType()))
|
|
->getElementType();
|
|
|
|
// FIXME: This upgrade is done during linking to support the C API. Once the
|
|
// old form is deprecated, we should move this upgrade to
|
|
// llvm::UpgradeGlobalVariable() and simplify the logic here and in
|
|
// Mapper::mapAppendingVariable() in ValueMapper.cpp.
|
|
StringRef Name = SrcGV->getName();
|
|
bool IsNewStructor = false;
|
|
bool IsOldStructor = false;
|
|
if (Name == "llvm.global_ctors" || Name == "llvm.global_dtors") {
|
|
if (cast<StructType>(EltTy)->getNumElements() == 3)
|
|
IsNewStructor = true;
|
|
else
|
|
IsOldStructor = true;
|
|
}
|
|
|
|
PointerType *VoidPtrTy = Type::getInt8Ty(SrcGV->getContext())->getPointerTo();
|
|
if (IsOldStructor) {
|
|
auto &ST = *cast<StructType>(EltTy);
|
|
Type *Tys[3] = {ST.getElementType(0), ST.getElementType(1), VoidPtrTy};
|
|
EltTy = StructType::get(SrcGV->getContext(), Tys, false);
|
|
}
|
|
|
|
uint64_t DstNumElements = 0;
|
|
if (DstGV) {
|
|
ArrayType *DstTy = cast<ArrayType>(DstGV->getValueType());
|
|
DstNumElements = DstTy->getNumElements();
|
|
|
|
if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage())
|
|
return stringErr(
|
|
"Linking globals named '" + SrcGV->getName() +
|
|
"': can only link appending global with another appending "
|
|
"global!");
|
|
|
|
// Check to see that they two arrays agree on type.
|
|
if (EltTy != DstTy->getElementType())
|
|
return stringErr("Appending variables with different element types!");
|
|
if (DstGV->isConstant() != SrcGV->isConstant())
|
|
return stringErr("Appending variables linked with different const'ness!");
|
|
|
|
if (DstGV->getAlignment() != SrcGV->getAlignment())
|
|
return stringErr(
|
|
"Appending variables with different alignment need to be linked!");
|
|
|
|
if (DstGV->getVisibility() != SrcGV->getVisibility())
|
|
return stringErr(
|
|
"Appending variables with different visibility need to be linked!");
|
|
|
|
if (DstGV->hasGlobalUnnamedAddr() != SrcGV->hasGlobalUnnamedAddr())
|
|
return stringErr(
|
|
"Appending variables with different unnamed_addr need to be linked!");
|
|
|
|
if (DstGV->getSection() != SrcGV->getSection())
|
|
return stringErr(
|
|
"Appending variables with different section name need to be linked!");
|
|
}
|
|
|
|
SmallVector<Constant *, 16> SrcElements;
|
|
getArrayElements(SrcGV->getInitializer(), SrcElements);
|
|
|
|
if (IsNewStructor) {
|
|
auto It = remove_if(SrcElements, [this](Constant *E) {
|
|
auto *Key =
|
|
dyn_cast<GlobalValue>(E->getAggregateElement(2)->stripPointerCasts());
|
|
if (!Key)
|
|
return false;
|
|
GlobalValue *DGV = getLinkedToGlobal(Key);
|
|
return !shouldLink(DGV, *Key);
|
|
});
|
|
SrcElements.erase(It, SrcElements.end());
|
|
}
|
|
uint64_t NewSize = DstNumElements + SrcElements.size();
|
|
ArrayType *NewType = ArrayType::get(EltTy, NewSize);
|
|
|
|
// Create the new global variable.
|
|
GlobalVariable *NG = new GlobalVariable(
|
|
DstM, NewType, SrcGV->isConstant(), SrcGV->getLinkage(),
|
|
/*init*/ nullptr, /*name*/ "", DstGV, SrcGV->getThreadLocalMode(),
|
|
SrcGV->getType()->getAddressSpace());
|
|
|
|
NG->copyAttributesFrom(SrcGV);
|
|
forceRenaming(NG, SrcGV->getName());
|
|
|
|
Constant *Ret = ConstantExpr::getBitCast(NG, TypeMap.get(SrcGV->getType()));
|
|
|
|
Mapper.scheduleMapAppendingVariable(*NG,
|
|
DstGV ? DstGV->getInitializer() : nullptr,
|
|
IsOldStructor, SrcElements);
|
|
|
|
// 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 IRLinker::shouldLink(GlobalValue *DGV, GlobalValue &SGV) {
|
|
if (ValuesToLink.count(&SGV) || SGV.hasLocalLinkage())
|
|
return true;
|
|
|
|
if (DGV && !DGV->isDeclarationForLinker())
|
|
return false;
|
|
|
|
if (SGV.isDeclaration() || DoneLinkingBodies)
|
|
return false;
|
|
|
|
// Callback to the client to give a chance to lazily add the Global to the
|
|
// list of value to link.
|
|
bool LazilyAdded = false;
|
|
AddLazyFor(SGV, [this, &LazilyAdded](GlobalValue &GV) {
|
|
maybeAdd(&GV);
|
|
LazilyAdded = true;
|
|
});
|
|
return LazilyAdded;
|
|
}
|
|
|
|
Expected<Constant *> IRLinker::linkGlobalValueProto(GlobalValue *SGV,
|
|
bool ForAlias) {
|
|
GlobalValue *DGV = getLinkedToGlobal(SGV);
|
|
|
|
bool ShouldLink = shouldLink(DGV, *SGV);
|
|
|
|
// just missing from map
|
|
if (ShouldLink) {
|
|
auto I = ValueMap.find(SGV);
|
|
if (I != ValueMap.end())
|
|
return cast<Constant>(I->second);
|
|
|
|
I = AliasValueMap.find(SGV);
|
|
if (I != AliasValueMap.end())
|
|
return cast<Constant>(I->second);
|
|
}
|
|
|
|
if (!ShouldLink && ForAlias)
|
|
DGV = nullptr;
|
|
|
|
// Handle the ultra special appending linkage case first.
|
|
assert(!DGV || SGV->hasAppendingLinkage() == DGV->hasAppendingLinkage());
|
|
if (SGV->hasAppendingLinkage())
|
|
return linkAppendingVarProto(cast_or_null<GlobalVariable>(DGV),
|
|
cast<GlobalVariable>(SGV));
|
|
|
|
GlobalValue *NewGV;
|
|
if (DGV && !ShouldLink) {
|
|
NewGV = DGV;
|
|
} else {
|
|
// If 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(SGV, ShouldLink || ForAlias);
|
|
if (ShouldLink || !ForAlias)
|
|
forceRenaming(NewGV, SGV->getName());
|
|
}
|
|
|
|
// Overloaded intrinsics have overloaded types names as part of their
|
|
// names. If we renamed overloaded types we should rename the intrinsic
|
|
// as well.
|
|
if (Function *F = dyn_cast<Function>(NewGV))
|
|
if (auto Remangled = Intrinsic::remangleIntrinsicFunction(F))
|
|
NewGV = Remangled.getValue();
|
|
|
|
if (ShouldLink || ForAlias) {
|
|
if (const Comdat *SC = SGV->getComdat()) {
|
|
if (auto *GO = dyn_cast<GlobalObject>(NewGV)) {
|
|
Comdat *DC = DstM.getOrInsertComdat(SC->getName());
|
|
DC->setSelectionKind(SC->getSelectionKind());
|
|
GO->setComdat(DC);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!ShouldLink && ForAlias)
|
|
NewGV->setLinkage(GlobalValue::InternalLinkage);
|
|
|
|
Constant *C = NewGV;
|
|
// Only create a bitcast if necessary. In particular, with
|
|
// DebugTypeODRUniquing we may reach metadata in the destination module
|
|
// containing a GV from the source module, in which case SGV will be
|
|
// the same as DGV and NewGV, and TypeMap.get() will assert since it
|
|
// assumes it is being invoked on a type in the source module.
|
|
if (DGV && NewGV != SGV) {
|
|
C = ConstantExpr::getPointerBitCastOrAddrSpaceCast(
|
|
NewGV, TypeMap.get(SGV->getType()));
|
|
}
|
|
|
|
if (DGV && NewGV != DGV) {
|
|
DGV->replaceAllUsesWith(
|
|
ConstantExpr::getPointerBitCastOrAddrSpaceCast(NewGV, DGV->getType()));
|
|
DGV->eraseFromParent();
|
|
}
|
|
|
|
return C;
|
|
}
|
|
|
|
/// Update the initializers in the Dest module now that all globals that may be
|
|
/// referenced are in Dest.
|
|
void IRLinker::linkGlobalVariable(GlobalVariable &Dst, GlobalVariable &Src) {
|
|
// Figure out what the initializer looks like in the dest module.
|
|
Mapper.scheduleMapGlobalInitializer(Dst, *Src.getInitializer());
|
|
}
|
|
|
|
/// 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.
|
|
Error IRLinker::linkFunctionBody(Function &Dst, Function &Src) {
|
|
assert(Dst.isDeclaration() && !Src.isDeclaration());
|
|
|
|
// Materialize if needed.
|
|
if (Error Err = Src.materialize())
|
|
return Err;
|
|
|
|
// Link in the operands without remapping.
|
|
if (Src.hasPrefixData())
|
|
Dst.setPrefixData(Src.getPrefixData());
|
|
if (Src.hasPrologueData())
|
|
Dst.setPrologueData(Src.getPrologueData());
|
|
if (Src.hasPersonalityFn())
|
|
Dst.setPersonalityFn(Src.getPersonalityFn());
|
|
|
|
// Copy over the metadata attachments without remapping.
|
|
Dst.copyMetadata(&Src, 0);
|
|
|
|
// Steal arguments and splice the body of Src into Dst.
|
|
Dst.stealArgumentListFrom(Src);
|
|
Dst.getBasicBlockList().splice(Dst.end(), Src.getBasicBlockList());
|
|
|
|
// Everything has been moved over. Remap it.
|
|
Mapper.scheduleRemapFunction(Dst);
|
|
return Error::success();
|
|
}
|
|
|
|
void IRLinker::linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src) {
|
|
Mapper.scheduleMapGlobalAliasee(Dst, *Src.getAliasee(), AliasMCID);
|
|
}
|
|
|
|
Error IRLinker::linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src) {
|
|
if (auto *F = dyn_cast<Function>(&Src))
|
|
return linkFunctionBody(cast<Function>(Dst), *F);
|
|
if (auto *GVar = dyn_cast<GlobalVariable>(&Src)) {
|
|
linkGlobalVariable(cast<GlobalVariable>(Dst), *GVar);
|
|
return Error::success();
|
|
}
|
|
linkAliasBody(cast<GlobalAlias>(Dst), cast<GlobalAlias>(Src));
|
|
return Error::success();
|
|
}
|
|
|
|
void IRLinker::prepareCompileUnitsForImport() {
|
|
NamedMDNode *SrcCompileUnits = SrcM->getNamedMetadata("llvm.dbg.cu");
|
|
if (!SrcCompileUnits)
|
|
return;
|
|
// When importing for ThinLTO, prevent importing of types listed on
|
|
// the DICompileUnit that we don't need a copy of in the importing
|
|
// module. They will be emitted by the originating module.
|
|
for (unsigned I = 0, E = SrcCompileUnits->getNumOperands(); I != E; ++I) {
|
|
auto *CU = cast<DICompileUnit>(SrcCompileUnits->getOperand(I));
|
|
assert(CU && "Expected valid compile unit");
|
|
// Enums, macros, and retained types don't need to be listed on the
|
|
// imported DICompileUnit. This means they will only be imported
|
|
// if reached from the mapped IR. Do this by setting their value map
|
|
// entries to nullptr, which will automatically prevent their importing
|
|
// when reached from the DICompileUnit during metadata mapping.
|
|
ValueMap.MD()[CU->getRawEnumTypes()].reset(nullptr);
|
|
ValueMap.MD()[CU->getRawMacros()].reset(nullptr);
|
|
ValueMap.MD()[CU->getRawRetainedTypes()].reset(nullptr);
|
|
// The original definition (or at least its debug info - if the variable is
|
|
// internalized an optimized away) will remain in the source module, so
|
|
// there's no need to import them.
|
|
// If LLVM ever does more advanced optimizations on global variables
|
|
// (removing/localizing write operations, for instance) that can track
|
|
// through debug info, this decision may need to be revisited - but do so
|
|
// with care when it comes to debug info size. Emitting small CUs containing
|
|
// only a few imported entities into every destination module may be very
|
|
// size inefficient.
|
|
ValueMap.MD()[CU->getRawGlobalVariables()].reset(nullptr);
|
|
|
|
// Imported entities only need to be mapped in if they have local
|
|
// scope, as those might correspond to an imported entity inside a
|
|
// function being imported (any locally scoped imported entities that
|
|
// don't end up referenced by an imported function will not be emitted
|
|
// into the object). Imported entities not in a local scope
|
|
// (e.g. on the namespace) only need to be emitted by the originating
|
|
// module. Create a list of the locally scoped imported entities, and
|
|
// replace the source CUs imported entity list with the new list, so
|
|
// only those are mapped in.
|
|
// FIXME: Locally-scoped imported entities could be moved to the
|
|
// functions they are local to instead of listing them on the CU, and
|
|
// we would naturally only link in those needed by function importing.
|
|
SmallVector<TrackingMDNodeRef, 4> AllImportedModules;
|
|
bool ReplaceImportedEntities = false;
|
|
for (auto *IE : CU->getImportedEntities()) {
|
|
DIScope *Scope = IE->getScope();
|
|
assert(Scope && "Invalid Scope encoding!");
|
|
if (isa<DILocalScope>(Scope))
|
|
AllImportedModules.emplace_back(IE);
|
|
else
|
|
ReplaceImportedEntities = true;
|
|
}
|
|
if (ReplaceImportedEntities) {
|
|
if (!AllImportedModules.empty())
|
|
CU->replaceImportedEntities(MDTuple::get(
|
|
CU->getContext(),
|
|
SmallVector<Metadata *, 16>(AllImportedModules.begin(),
|
|
AllImportedModules.end())));
|
|
else
|
|
// If there were no local scope imported entities, we can map
|
|
// the whole list to nullptr.
|
|
ValueMap.MD()[CU->getRawImportedEntities()].reset(nullptr);
|
|
}
|
|
}
|
|
}
|
|
|
|
/// Insert all of the named MDNodes in Src into the Dest module.
|
|
void IRLinker::linkNamedMDNodes() {
|
|
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());
|
|
// Add Src elements into Dest node.
|
|
for (const MDNode *Op : NMD.operands())
|
|
DestNMD->addOperand(Mapper.mapMDNode(*Op));
|
|
}
|
|
}
|
|
|
|
/// Merge the linker flags in Src into the Dest module.
|
|
Error IRLinker::linkModuleFlagsMetadata() {
|
|
// If the source module has no module flags, we are done.
|
|
const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
|
|
if (!SrcModFlags)
|
|
return Error::success();
|
|
|
|
// If the destination module doesn't have module flags yet, then just copy
|
|
// over the source module's flags.
|
|
NamedMDNode *DstModFlags = DstM.getOrInsertModuleFlagsMetadata();
|
|
if (DstModFlags->getNumOperands() == 0) {
|
|
for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
|
|
DstModFlags->addOperand(SrcModFlags->getOperand(I));
|
|
|
|
return Error::success();
|
|
}
|
|
|
|
// First build a map of the existing module flags and requirements.
|
|
DenseMap<MDString *, std::pair<MDNode *, unsigned>> Flags;
|
|
SmallSetVector<MDNode *, 16> Requirements;
|
|
for (unsigned I = 0, E = DstModFlags->getNumOperands(); I != E; ++I) {
|
|
MDNode *Op = DstModFlags->getOperand(I);
|
|
ConstantInt *Behavior = mdconst::extract<ConstantInt>(Op->getOperand(0));
|
|
MDString *ID = cast<MDString>(Op->getOperand(1));
|
|
|
|
if (Behavior->getZExtValue() == Module::Require) {
|
|
Requirements.insert(cast<MDNode>(Op->getOperand(2)));
|
|
} else {
|
|
Flags[ID] = std::make_pair(Op, I);
|
|
}
|
|
}
|
|
|
|
// Merge in the flags from the source module, and also collect its set of
|
|
// requirements.
|
|
for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I) {
|
|
MDNode *SrcOp = SrcModFlags->getOperand(I);
|
|
ConstantInt *SrcBehavior =
|
|
mdconst::extract<ConstantInt>(SrcOp->getOperand(0));
|
|
MDString *ID = cast<MDString>(SrcOp->getOperand(1));
|
|
MDNode *DstOp;
|
|
unsigned DstIndex;
|
|
std::tie(DstOp, DstIndex) = Flags.lookup(ID);
|
|
unsigned SrcBehaviorValue = SrcBehavior->getZExtValue();
|
|
|
|
// If this is a requirement, add it and continue.
|
|
if (SrcBehaviorValue == Module::Require) {
|
|
// If the destination module does not already have this requirement, add
|
|
// it.
|
|
if (Requirements.insert(cast<MDNode>(SrcOp->getOperand(2)))) {
|
|
DstModFlags->addOperand(SrcOp);
|
|
}
|
|
continue;
|
|
}
|
|
|
|
// If there is no existing flag with this ID, just add it.
|
|
if (!DstOp) {
|
|
Flags[ID] = std::make_pair(SrcOp, DstModFlags->getNumOperands());
|
|
DstModFlags->addOperand(SrcOp);
|
|
continue;
|
|
}
|
|
|
|
// Otherwise, perform a merge.
|
|
ConstantInt *DstBehavior =
|
|
mdconst::extract<ConstantInt>(DstOp->getOperand(0));
|
|
unsigned DstBehaviorValue = DstBehavior->getZExtValue();
|
|
|
|
auto overrideDstValue = [&]() {
|
|
DstModFlags->setOperand(DstIndex, SrcOp);
|
|
Flags[ID].first = SrcOp;
|
|
};
|
|
|
|
// If either flag has override behavior, handle it first.
|
|
if (DstBehaviorValue == Module::Override) {
|
|
// Diagnose inconsistent flags which both have override behavior.
|
|
if (SrcBehaviorValue == Module::Override &&
|
|
SrcOp->getOperand(2) != DstOp->getOperand(2))
|
|
return stringErr("linking module flags '" + ID->getString() +
|
|
"': IDs have conflicting override values");
|
|
continue;
|
|
} else if (SrcBehaviorValue == Module::Override) {
|
|
// Update the destination flag to that of the source.
|
|
overrideDstValue();
|
|
continue;
|
|
}
|
|
|
|
// Diagnose inconsistent merge behavior types.
|
|
if (SrcBehaviorValue != DstBehaviorValue)
|
|
return stringErr("linking module flags '" + ID->getString() +
|
|
"': IDs have conflicting behaviors");
|
|
|
|
auto replaceDstValue = [&](MDNode *New) {
|
|
Metadata *FlagOps[] = {DstOp->getOperand(0), ID, New};
|
|
MDNode *Flag = MDNode::get(DstM.getContext(), FlagOps);
|
|
DstModFlags->setOperand(DstIndex, Flag);
|
|
Flags[ID].first = Flag;
|
|
};
|
|
|
|
// Perform the merge for standard behavior types.
|
|
switch (SrcBehaviorValue) {
|
|
case Module::Require:
|
|
case Module::Override:
|
|
llvm_unreachable("not possible");
|
|
case Module::Error: {
|
|
// Emit an error if the values differ.
|
|
if (SrcOp->getOperand(2) != DstOp->getOperand(2))
|
|
return stringErr("linking module flags '" + ID->getString() +
|
|
"': IDs have conflicting values");
|
|
continue;
|
|
}
|
|
case Module::Warning: {
|
|
// Emit a warning if the values differ.
|
|
if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
|
|
std::string str;
|
|
raw_string_ostream(str)
|
|
<< "linking module flags '" << ID->getString()
|
|
<< "': IDs have conflicting values ('" << *SrcOp->getOperand(2)
|
|
<< "' from " << SrcM->getModuleIdentifier() << " with '"
|
|
<< *DstOp->getOperand(2) << "' from " << DstM.getModuleIdentifier()
|
|
<< ')';
|
|
emitWarning(str);
|
|
}
|
|
continue;
|
|
}
|
|
case Module::Max: {
|
|
ConstantInt *DstValue =
|
|
mdconst::extract<ConstantInt>(DstOp->getOperand(2));
|
|
ConstantInt *SrcValue =
|
|
mdconst::extract<ConstantInt>(SrcOp->getOperand(2));
|
|
if (SrcValue->getZExtValue() > DstValue->getZExtValue())
|
|
overrideDstValue();
|
|
break;
|
|
}
|
|
case Module::Append: {
|
|
MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
|
|
MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
|
|
SmallVector<Metadata *, 8> MDs;
|
|
MDs.reserve(DstValue->getNumOperands() + SrcValue->getNumOperands());
|
|
MDs.append(DstValue->op_begin(), DstValue->op_end());
|
|
MDs.append(SrcValue->op_begin(), SrcValue->op_end());
|
|
|
|
replaceDstValue(MDNode::get(DstM.getContext(), MDs));
|
|
break;
|
|
}
|
|
case Module::AppendUnique: {
|
|
SmallSetVector<Metadata *, 16> Elts;
|
|
MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
|
|
MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
|
|
Elts.insert(DstValue->op_begin(), DstValue->op_end());
|
|
Elts.insert(SrcValue->op_begin(), SrcValue->op_end());
|
|
|
|
replaceDstValue(MDNode::get(DstM.getContext(),
|
|
makeArrayRef(Elts.begin(), Elts.end())));
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Check all of the requirements.
|
|
for (unsigned I = 0, E = Requirements.size(); I != E; ++I) {
|
|
MDNode *Requirement = Requirements[I];
|
|
MDString *Flag = cast<MDString>(Requirement->getOperand(0));
|
|
Metadata *ReqValue = Requirement->getOperand(1);
|
|
|
|
MDNode *Op = Flags[Flag].first;
|
|
if (!Op || Op->getOperand(2) != ReqValue)
|
|
return stringErr("linking module flags '" + Flag->getString() +
|
|
"': does not have the required value");
|
|
}
|
|
return Error::success();
|
|
}
|
|
|
|
/// Return InlineAsm adjusted with target-specific directives if required.
|
|
/// For ARM and Thumb, we have to add directives to select the appropriate ISA
|
|
/// to support mixing module-level inline assembly from ARM and Thumb modules.
|
|
static std::string adjustInlineAsm(const std::string &InlineAsm,
|
|
const Triple &Triple) {
|
|
if (Triple.getArch() == Triple::thumb || Triple.getArch() == Triple::thumbeb)
|
|
return ".text\n.balign 2\n.thumb\n" + InlineAsm;
|
|
if (Triple.getArch() == Triple::arm || Triple.getArch() == Triple::armeb)
|
|
return ".text\n.balign 4\n.arm\n" + InlineAsm;
|
|
return InlineAsm;
|
|
}
|
|
|
|
Error IRLinker::run() {
|
|
// Ensure metadata materialized before value mapping.
|
|
if (SrcM->getMaterializer())
|
|
if (Error Err = SrcM->getMaterializer()->materializeMetadata())
|
|
return Err;
|
|
|
|
// 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 (SrcM->getDataLayout() != DstM.getDataLayout()) {
|
|
emitWarning("Linking two modules of different data layouts: '" +
|
|
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());
|
|
|
|
Triple SrcTriple(SrcM->getTargetTriple()), DstTriple(DstM.getTargetTriple());
|
|
|
|
if (!SrcM->getTargetTriple().empty()&&
|
|
!SrcTriple.isCompatibleWith(DstTriple))
|
|
emitWarning("Linking two modules of different target triples: " +
|
|
SrcM->getModuleIdentifier() + "' is '" +
|
|
SrcM->getTargetTriple() + "' whereas '" +
|
|
DstM.getModuleIdentifier() + "' is '" + DstM.getTargetTriple() +
|
|
"'\n");
|
|
|
|
DstM.setTargetTriple(SrcTriple.merge(DstTriple));
|
|
|
|
// Append the module inline asm string.
|
|
if (!IsPerformingImport && !SrcM->getModuleInlineAsm().empty()) {
|
|
std::string SrcModuleInlineAsm = adjustInlineAsm(SrcM->getModuleInlineAsm(),
|
|
SrcTriple);
|
|
if (DstM.getModuleInlineAsm().empty())
|
|
DstM.setModuleInlineAsm(SrcModuleInlineAsm);
|
|
else
|
|
DstM.setModuleInlineAsm(DstM.getModuleInlineAsm() + "\n" +
|
|
SrcModuleInlineAsm);
|
|
}
|
|
|
|
// Loop over all of the linked values to compute type mappings.
|
|
computeTypeMapping();
|
|
|
|
std::reverse(Worklist.begin(), Worklist.end());
|
|
while (!Worklist.empty()) {
|
|
GlobalValue *GV = Worklist.back();
|
|
Worklist.pop_back();
|
|
|
|
// Already mapped.
|
|
if (ValueMap.find(GV) != ValueMap.end() ||
|
|
AliasValueMap.find(GV) != AliasValueMap.end())
|
|
continue;
|
|
|
|
assert(!GV->isDeclaration());
|
|
Mapper.mapValue(*GV);
|
|
if (FoundError)
|
|
return std::move(*FoundError);
|
|
}
|
|
|
|
// Note that we are done linking global value bodies. This prevents
|
|
// metadata linking from creating new references.
|
|
DoneLinkingBodies = true;
|
|
Mapper.addFlags(RF_NullMapMissingGlobalValues);
|
|
|
|
// Remap all of the named MDNodes in Src into the DstM module. We do this
|
|
// after linking GlobalValues so that MDNodes that reference GlobalValues
|
|
// are properly remapped.
|
|
linkNamedMDNodes();
|
|
|
|
// Merge the module flags into the DstM module.
|
|
return linkModuleFlagsMetadata();
|
|
}
|
|
|
|
IRMover::StructTypeKeyInfo::KeyTy::KeyTy(ArrayRef<Type *> E, bool P)
|
|
: ETypes(E), IsPacked(P) {}
|
|
|
|
IRMover::StructTypeKeyInfo::KeyTy::KeyTy(const StructType *ST)
|
|
: ETypes(ST->elements()), IsPacked(ST->isPacked()) {}
|
|
|
|
bool IRMover::StructTypeKeyInfo::KeyTy::operator==(const KeyTy &That) const {
|
|
return IsPacked == That.IsPacked && ETypes == That.ETypes;
|
|
}
|
|
|
|
bool IRMover::StructTypeKeyInfo::KeyTy::operator!=(const KeyTy &That) const {
|
|
return !this->operator==(That);
|
|
}
|
|
|
|
StructType *IRMover::StructTypeKeyInfo::getEmptyKey() {
|
|
return DenseMapInfo<StructType *>::getEmptyKey();
|
|
}
|
|
|
|
StructType *IRMover::StructTypeKeyInfo::getTombstoneKey() {
|
|
return DenseMapInfo<StructType *>::getTombstoneKey();
|
|
}
|
|
|
|
unsigned IRMover::StructTypeKeyInfo::getHashValue(const KeyTy &Key) {
|
|
return hash_combine(hash_combine_range(Key.ETypes.begin(), Key.ETypes.end()),
|
|
Key.IsPacked);
|
|
}
|
|
|
|
unsigned IRMover::StructTypeKeyInfo::getHashValue(const StructType *ST) {
|
|
return getHashValue(KeyTy(ST));
|
|
}
|
|
|
|
bool IRMover::StructTypeKeyInfo::isEqual(const KeyTy &LHS,
|
|
const StructType *RHS) {
|
|
if (RHS == getEmptyKey() || RHS == getTombstoneKey())
|
|
return false;
|
|
return LHS == KeyTy(RHS);
|
|
}
|
|
|
|
bool IRMover::StructTypeKeyInfo::isEqual(const StructType *LHS,
|
|
const StructType *RHS) {
|
|
if (RHS == getEmptyKey() || RHS == getTombstoneKey())
|
|
return LHS == RHS;
|
|
return KeyTy(LHS) == KeyTy(RHS);
|
|
}
|
|
|
|
void IRMover::IdentifiedStructTypeSet::addNonOpaque(StructType *Ty) {
|
|
assert(!Ty->isOpaque());
|
|
NonOpaqueStructTypes.insert(Ty);
|
|
}
|
|
|
|
void IRMover::IdentifiedStructTypeSet::switchToNonOpaque(StructType *Ty) {
|
|
assert(!Ty->isOpaque());
|
|
NonOpaqueStructTypes.insert(Ty);
|
|
bool Removed = OpaqueStructTypes.erase(Ty);
|
|
(void)Removed;
|
|
assert(Removed);
|
|
}
|
|
|
|
void IRMover::IdentifiedStructTypeSet::addOpaque(StructType *Ty) {
|
|
assert(Ty->isOpaque());
|
|
OpaqueStructTypes.insert(Ty);
|
|
}
|
|
|
|
StructType *
|
|
IRMover::IdentifiedStructTypeSet::findNonOpaque(ArrayRef<Type *> ETypes,
|
|
bool IsPacked) {
|
|
IRMover::StructTypeKeyInfo::KeyTy Key(ETypes, IsPacked);
|
|
auto I = NonOpaqueStructTypes.find_as(Key);
|
|
return I == NonOpaqueStructTypes.end() ? nullptr : *I;
|
|
}
|
|
|
|
bool IRMover::IdentifiedStructTypeSet::hasType(StructType *Ty) {
|
|
if (Ty->isOpaque())
|
|
return OpaqueStructTypes.count(Ty);
|
|
auto I = NonOpaqueStructTypes.find(Ty);
|
|
return I == NonOpaqueStructTypes.end() ? false : *I == Ty;
|
|
}
|
|
|
|
IRMover::IRMover(Module &M) : Composite(M) {
|
|
TypeFinder StructTypes;
|
|
StructTypes.run(M, /* OnlyNamed */ false);
|
|
for (StructType *Ty : StructTypes) {
|
|
if (Ty->isOpaque())
|
|
IdentifiedStructTypes.addOpaque(Ty);
|
|
else
|
|
IdentifiedStructTypes.addNonOpaque(Ty);
|
|
}
|
|
// Self-map metadatas in the destination module. This is needed when
|
|
// DebugTypeODRUniquing is enabled on the LLVMContext, since metadata in the
|
|
// destination module may be reached from the source module.
|
|
for (auto *MD : StructTypes.getVisitedMetadata()) {
|
|
SharedMDs[MD].reset(const_cast<MDNode *>(MD));
|
|
}
|
|
}
|
|
|
|
Error IRMover::move(
|
|
std::unique_ptr<Module> Src, ArrayRef<GlobalValue *> ValuesToLink,
|
|
std::function<void(GlobalValue &, ValueAdder Add)> AddLazyFor,
|
|
bool IsPerformingImport) {
|
|
IRLinker TheIRLinker(Composite, SharedMDs, IdentifiedStructTypes,
|
|
std::move(Src), ValuesToLink, std::move(AddLazyFor),
|
|
IsPerformingImport);
|
|
Error E = TheIRLinker.run();
|
|
Composite.dropTriviallyDeadConstantArrays();
|
|
return E;
|
|
}
|