-//===- lib/Linker/LinkModules.cpp - Module Linker Implementation ----------===//
+ //===- lib/Linker/LinkModules.cpp - Module Linker Implementation ----------===//
//
// The LLVM Compiler Infrastructure
//
#include "llvm/Assembly/Writer.h"
#include "llvm/Support/Streams.h"
#include "llvm/System/Path.h"
+#include "llvm/ADT/DenseMap.h"
#include <sstream>
using namespace llvm;
return true;
}
-// ToStr - Simple wrapper function to convert a type to a string.
-static std::string ToStr(const Type *Ty, const Module *M) {
- std::ostringstream OS;
- WriteTypeSymbolic(OS, Ty, M);
- return OS.str();
-}
-
-//
// Function: ResolveTypes()
//
// Description:
return false;
}
+/// LinkerTypeMap - This implements a map of types that is stable
+/// even if types are resolved/refined to other types. This is not a general
+/// purpose map, it is specific to the linker's use.
+namespace {
+class LinkerTypeMap : public AbstractTypeUser {
+ typedef DenseMap<const Type*, PATypeHolder> TheMapTy;
+ TheMapTy TheMap;
+
+ LinkerTypeMap(const LinkerTypeMap&); // DO NOT IMPLEMENT
+ void operator=(const LinkerTypeMap&); // DO NOT IMPLEMENT
+public:
+ LinkerTypeMap() {}
+ ~LinkerTypeMap() {
+ for (DenseMap<const Type*, PATypeHolder>::iterator I = TheMap.begin(),
+ E = TheMap.end(); I != E; ++I)
+ I->first->removeAbstractTypeUser(this);
+ }
+
+ /// lookup - Return the value for the specified type or null if it doesn't
+ /// exist.
+ const Type *lookup(const Type *Ty) const {
+ TheMapTy::const_iterator I = TheMap.find(Ty);
+ if (I != TheMap.end()) return I->second;
+ return 0;
+ }
+
+ /// erase - Remove the specified type, returning true if it was in the set.
+ bool erase(const Type *Ty) {
+ if (!TheMap.erase(Ty))
+ return false;
+ if (Ty->isAbstract())
+ Ty->removeAbstractTypeUser(this);
+ return true;
+ }
+
+ /// insert - This returns true if the pointer was new to the set, false if it
+ /// was already in the set.
+ bool insert(const Type *Src, const Type *Dst) {
+ if (!TheMap.insert(std::make_pair(Src, PATypeHolder(Dst))).second)
+ return false; // Already in map.
+ if (Src->isAbstract())
+ Src->addAbstractTypeUser(this);
+ return true;
+ }
+
+protected:
+ /// refineAbstractType - The callback method invoked when an abstract type is
+ /// resolved to another type. An object must override this method to update
+ /// its internal state to reference NewType instead of OldType.
+ ///
+ virtual void refineAbstractType(const DerivedType *OldTy,
+ const Type *NewTy) {
+ TheMapTy::iterator I = TheMap.find(OldTy);
+ const Type *DstTy = I->second;
+
+ TheMap.erase(I);
+ if (OldTy->isAbstract())
+ OldTy->removeAbstractTypeUser(this);
+
+ // Don't reinsert into the map if the key is concrete now.
+ if (NewTy->isAbstract())
+ insert(NewTy, DstTy);
+ }
+
+ /// The other case which AbstractTypeUsers must be aware of is when a type
+ /// makes the transition from being abstract (where it has clients on it's
+ /// AbstractTypeUsers list) to concrete (where it does not). This method
+ /// notifies ATU's when this occurs for a type.
+ virtual void typeBecameConcrete(const DerivedType *AbsTy) {
+ TheMap.erase(AbsTy);
+ AbsTy->removeAbstractTypeUser(this);
+ }
+
+ // for debugging...
+ virtual void dump() const {
+ cerr << "AbstractTypeSet!\n";
+ }
+};
+}
+
+
// RecursiveResolveTypes - This is just like ResolveTypes, except that it
// recurses down into derived types, merging the used types if the parent types
// are compatible.
-static bool RecursiveResolveTypesI(const PATypeHolder &DestTy,
- const PATypeHolder &SrcTy,
- std::vector<std::pair<PATypeHolder, PATypeHolder> > &Pointers) {
- const Type *SrcTyT = SrcTy.get();
- const Type *DestTyT = DestTy.get();
- if (DestTyT == SrcTyT) return false; // If already equal, noop
+static bool RecursiveResolveTypesI(const Type *DstTy, const Type *SrcTy,
+ LinkerTypeMap &Pointers) {
+ if (DstTy == SrcTy) return false; // If already equal, noop
// If we found our opaque type, resolve it now!
- if (isa<OpaqueType>(DestTyT) || isa<OpaqueType>(SrcTyT))
- return ResolveTypes(DestTyT, SrcTyT);
+ if (isa<OpaqueType>(DstTy) || isa<OpaqueType>(SrcTy))
+ return ResolveTypes(DstTy, SrcTy);
// Two types cannot be resolved together if they are of different primitive
// type. For example, we cannot resolve an int to a float.
- if (DestTyT->getTypeID() != SrcTyT->getTypeID()) return true;
+ if (DstTy->getTypeID() != SrcTy->getTypeID()) return true;
+ // If neither type is abstract, then they really are just different types.
+ if (!DstTy->isAbstract() && !SrcTy->isAbstract())
+ return true;
+
// Otherwise, resolve the used type used by this derived type...
- switch (DestTyT->getTypeID()) {
+ switch (DstTy->getTypeID()) {
default:
return true;
case Type::FunctionTyID: {
- const FunctionType *DstFT = cast<FunctionType>(DestTyT);
- const FunctionType *SrcFT = cast<FunctionType>(SrcTyT);
+ const FunctionType *DstFT = cast<FunctionType>(DstTy);
+ const FunctionType *SrcFT = cast<FunctionType>(SrcTy);
if (DstFT->isVarArg() != SrcFT->isVarArg() ||
DstFT->getNumContainedTypes() != SrcFT->getNumContainedTypes())
return true;
- for (unsigned i = 0, e = DstFT->getNumContainedTypes(); i != e; ++i)
- if (RecursiveResolveTypesI(DstFT->getContainedType(i),
- SrcFT->getContainedType(i), Pointers))
+
+ // Use TypeHolder's so recursive resolution won't break us.
+ PATypeHolder ST(SrcFT), DT(DstFT);
+ for (unsigned i = 0, e = DstFT->getNumContainedTypes(); i != e; ++i) {
+ const Type *SE = ST->getContainedType(i), *DE = DT->getContainedType(i);
+ if (SE != DE && RecursiveResolveTypesI(DE, SE, Pointers))
return true;
+ }
return false;
}
case Type::StructTyID: {
- const StructType *DstST = cast<StructType>(DestTyT);
- const StructType *SrcST = cast<StructType>(SrcTyT);
+ const StructType *DstST = cast<StructType>(DstTy);
+ const StructType *SrcST = cast<StructType>(SrcTy);
if (DstST->getNumContainedTypes() != SrcST->getNumContainedTypes())
return true;
- for (unsigned i = 0, e = DstST->getNumContainedTypes(); i != e; ++i)
- if (RecursiveResolveTypesI(DstST->getContainedType(i),
- SrcST->getContainedType(i), Pointers))
+
+ PATypeHolder ST(SrcST), DT(DstST);
+ for (unsigned i = 0, e = DstST->getNumContainedTypes(); i != e; ++i) {
+ const Type *SE = ST->getContainedType(i), *DE = DT->getContainedType(i);
+ if (SE != DE && RecursiveResolveTypesI(DE, SE, Pointers))
return true;
+ }
return false;
}
case Type::ArrayTyID: {
- const ArrayType *DAT = cast<ArrayType>(DestTy.get());
- const ArrayType *SAT = cast<ArrayType>(SrcTy.get());
+ const ArrayType *DAT = cast<ArrayType>(DstTy);
+ const ArrayType *SAT = cast<ArrayType>(SrcTy);
if (DAT->getNumElements() != SAT->getNumElements()) return true;
return RecursiveResolveTypesI(DAT->getElementType(), SAT->getElementType(),
Pointers);
}
case Type::VectorTyID: {
- const VectorType *DVT = cast<VectorType>(DestTy.get());
- const VectorType *SVT = cast<VectorType>(SrcTy.get());
+ const VectorType *DVT = cast<VectorType>(DstTy);
+ const VectorType *SVT = cast<VectorType>(SrcTy);
if (DVT->getNumElements() != SVT->getNumElements()) return true;
return RecursiveResolveTypesI(DVT->getElementType(), SVT->getElementType(),
Pointers);
}
case Type::PointerTyID: {
- const PointerType *DstPT = cast<PointerType>(DestTy.get());
- const PointerType *SrcPT = cast<PointerType>(SrcTy.get());
+ const PointerType *DstPT = cast<PointerType>(DstTy);
+ const PointerType *SrcPT = cast<PointerType>(SrcTy);
if (DstPT->getAddressSpace() != SrcPT->getAddressSpace())
return true;
// If this is a pointer type, check to see if we have already seen it. If
// so, we are in a recursive branch. Cut off the search now. We cannot use
// an associative container for this search, because the type pointers (keys
- // in the container) change whenever types get resolved...
- for (unsigned i = 0, e = Pointers.size(); i != e; ++i)
- if (Pointers[i].first == DestTy)
- return Pointers[i].second != SrcTy;
-
+ // in the container) change whenever types get resolved.
+ if (SrcPT->isAbstract())
+ if (const Type *ExistingDestTy = Pointers.lookup(SrcPT))
+ return ExistingDestTy != DstPT;
+
+ if (DstPT->isAbstract())
+ if (const Type *ExistingSrcTy = Pointers.lookup(DstPT))
+ return ExistingSrcTy != SrcPT;
// Otherwise, add the current pointers to the vector to stop recursion on
// this pair.
- Pointers.push_back(std::make_pair(DestTyT, SrcTyT));
+ if (DstPT->isAbstract())
+ Pointers.insert(DstPT, SrcPT);
+ if (SrcPT->isAbstract())
+ Pointers.insert(SrcPT, DstPT);
+
return RecursiveResolveTypesI(DstPT->getElementType(),
SrcPT->getElementType(), Pointers);
}
}
}
-static bool RecursiveResolveTypes(const PATypeHolder &DestTy,
- const PATypeHolder &SrcTy) {
- std::vector<std::pair<PATypeHolder, PATypeHolder> > PointerTypes;
+static bool RecursiveResolveTypes(const Type *DestTy, const Type *SrcTy) {
+ LinkerTypeMap PointerTypes;
return RecursiveResolveTypesI(DestTy, SrcTy, PointerTypes);
}
// two types: { int* } and { opaque* }
for (unsigned i = 0, e = DelayedTypesToResolve.size(); i != e; ++i) {
const std::string &Name = DelayedTypesToResolve[i];
- PATypeHolder T1(SrcST->lookup(Name));
- PATypeHolder T2(DestST->lookup(Name));
-
- if (!RecursiveResolveTypes(T2, T1)) {
+ if (!RecursiveResolveTypes(SrcST->lookup(Name), DestST->lookup(Name))) {
// We are making progress!
DelayedTypesToResolve.erase(DelayedTypesToResolve.begin()+i);
return false;
}
+#ifndef NDEBUG
static void PrintMap(const std::map<const Value*, Value*> &M) {
for (std::map<const Value*, Value*>::const_iterator I = M.begin(), E =M.end();
I != E; ++I) {
cerr << "\n";
}
}
+#endif
// RemapOperand - Use ValueMap to convert constants from one module to another.
for (unsigned i = 0, e = CE->getNumOperands(); i != e; ++i)
Ops.push_back(cast<Constant>(RemapOperand(CE->getOperand(i),ValueMap)));
Result = CE->getWithOperands(Ops);
- } else if (isa<GlobalValue>(CPV)) {
- assert(0 && "Unmapped global?");
} else {
+ assert(!isa<GlobalValue>(CPV) && "Unmapped global?");
assert(0 && "Unknown type of derived type constant value!");
}
} else if (isa<InlineAsm>(In)) {
return Result;
}
-
+#ifndef NDEBUG
cerr << "LinkModules ValueMap: \n";
PrintMap(ValueMap);
cerr << "Couldn't remap value: " << (void*)In << " " << *In << "\n";
assert(0 && "Couldn't remap value!");
+#endif
return 0;
}
// If there is a conflict, rename the conflict.
if (GlobalValue *ConflictGV = cast_or_null<GlobalValue>(ST.lookup(Name))) {
- assert(ConflictGV->hasInternalLinkage() &&
+ assert(ConflictGV->hasLocalLinkage() &&
"Not conflicting with a static global, should link instead!");
GV->takeName(ConflictGV);
ConflictGV->setName(Name); // This will cause ConflictGV to get renamed
static bool GetLinkageResult(GlobalValue *Dest, const GlobalValue *Src,
GlobalValue::LinkageTypes <, bool &LinkFromSrc,
std::string *Err) {
- assert((!Dest || !Src->hasInternalLinkage()) &&
+ assert((!Dest || !Src->hasLocalLinkage()) &&
"If Src has internal linkage, Dest shouldn't be set!");
if (!Dest) {
// Linking something to nothing.
"': can only link appending global with another appending global!");
LinkFromSrc = true; // Special cased.
LT = Src->getLinkage();
- } else if (Src->hasWeakLinkage() || Src->hasLinkOnceLinkage() ||
- Src->hasCommonLinkage()) {
+ } else if (Src->mayBeOverridden()) {
// At this point we know that Dest has LinkOnce, External*, Weak, Common,
// or DLL* linkage.
- if ((Dest->hasLinkOnceLinkage() &&
+ if ((Dest->hasLinkOnceLinkage() &&
(Src->hasWeakLinkage() || Src->hasCommonLinkage())) ||
Dest->hasExternalWeakLinkage()) {
LinkFromSrc = true;
LinkFromSrc = false;
LT = Dest->getLinkage();
}
- } else if (Dest->hasWeakLinkage() || Dest->hasLinkOnceLinkage() ||
- Dest->hasCommonLinkage()) {
+ } else if (Dest->mayBeOverridden()) {
// At this point we know that Src has External* or DLL* linkage.
if (Src->hasExternalWeakLinkage()) {
LinkFromSrc = false;
std::map<const Value*, Value*> &ValueMap,
std::multimap<std::string, GlobalVariable *> &AppendingVars,
std::string *Err) {
+ ValueSymbolTable &DestSymTab = Dest->getValueSymbolTable();
+
// Loop over all of the globals in the src module, mapping them over as we go
- for (Module::const_global_iterator I = Src->global_begin(), E = Src->global_end();
- I != E; ++I) {
+ for (Module::const_global_iterator I = Src->global_begin(),
+ E = Src->global_end(); I != E; ++I) {
const GlobalVariable *SGV = I;
GlobalValue *DGV = 0;
- // Check to see if may have to link the global with the global
- if (SGV->hasName() && !SGV->hasInternalLinkage()) {
- DGV = Dest->getGlobalVariable(SGV->getName());
- if (DGV && DGV->getType() != SGV->getType())
- // If types don't agree due to opaque types, try to resolve them.
- RecursiveResolveTypes(SGV->getType(), DGV->getType());
- }
-
- // Check to see if may have to link the global with the alias
- if (!DGV && SGV->hasName() && !SGV->hasInternalLinkage()) {
- DGV = Dest->getNamedAlias(SGV->getName());
- if (DGV && DGV->getType() != SGV->getType())
- // If types don't agree due to opaque types, try to resolve them.
- RecursiveResolveTypes(SGV->getType(), DGV->getType());
- }
-
- if (DGV && DGV->hasInternalLinkage())
+ // Check to see if may have to link the global with the global, alias or
+ // function.
+ if (SGV->hasName() && !SGV->hasLocalLinkage())
+ DGV = cast_or_null<GlobalValue>(DestSymTab.lookup(SGV->getNameStart(),
+ SGV->getNameEnd()));
+
+ // 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 && DGV->hasLocalLinkage())
DGV = 0;
+
+ // If types don't agree due to opaque types, try to resolve them.
+ if (DGV && DGV->getType() != SGV->getType())
+ RecursiveResolveTypes(SGV->getType(), DGV->getType());
assert((SGV->hasInitializer() || SGV->hasExternalWeakLinkage() ||
SGV->hasExternalLinkage() || SGV->hasDLLImportLinkage()) &&
if (GetLinkageResult(DGV, SGV, NewLinkage, LinkFromSrc, Err))
return true;
- if (!DGV) {
+ if (DGV == 0) {
// No linking to be performed, simply create an identical version of the
// symbol over in the dest module... the initializer will be filled in
- // later by LinkGlobalInits...
+ // later by LinkGlobalInits.
GlobalVariable *NewDGV =
new GlobalVariable(SGV->getType()->getElementType(),
SGV->isConstant(), SGV->getLinkage(), /*init*/0,
- SGV->getName(), Dest);
+ SGV->getName(), Dest, false,
+ SGV->getType()->getAddressSpace());
// Propagate alignment, visibility and section info.
CopyGVAttributes(NewDGV, SGV);
// If the LLVM runtime renamed the global, but it is an externally visible
// symbol, DGV must be an existing global with internal linkage. Rename
// it.
- if (NewDGV->getName() != SGV->getName() && !NewDGV->hasInternalLinkage())
+ if (!NewDGV->hasLocalLinkage() && NewDGV->getName() != SGV->getName())
ForceRenaming(NewDGV, SGV->getName());
- // Make sure to remember this mapping...
+ // Make sure to remember this mapping.
ValueMap[SGV] = NewDGV;
+ // Keep track that this is an appending variable.
if (SGV->hasAppendingLinkage())
- // Keep track that this is an appending variable...
AppendingVars.insert(std::make_pair(SGV->getName(), NewDGV));
- } else if (DGV->hasAppendingLinkage()) {
+ continue;
+ }
+
+ // If the visibilities of the symbols disagree and the destination is a
+ // prototype, take the visibility of its input.
+ if (DGV->isDeclaration())
+ DGV->setVisibility(SGV->getVisibility());
+
+ if (DGV->hasAppendingLinkage()) {
// No linking is performed yet. Just insert a new copy of the global, and
// keep track of the fact that it is an appending variable in the
// AppendingVars map. The name is cleared out so that no linkage is
GlobalVariable *NewDGV =
new GlobalVariable(SGV->getType()->getElementType(),
SGV->isConstant(), SGV->getLinkage(), /*init*/0,
- "", Dest);
+ "", Dest, false,
+ SGV->getType()->getAddressSpace());
// Set alignment allowing CopyGVAttributes merge it with alignment of SGV.
NewDGV->setAlignment(DGV->getAlignment());
// Keep track that this is an appending variable...
AppendingVars.insert(std::make_pair(SGV->getName(), NewDGV));
- } else if (GlobalAlias *DGA = dyn_cast<GlobalAlias>(DGV)) {
- // SGV is global, but DGV is alias. The only valid mapping is when SGV is
- // external declaration, which is effectively a no-op. Also make sure
- // linkage calculation was correct.
- if (SGV->isDeclaration() && !LinkFromSrc) {
- // Make sure to remember this mapping...
- ValueMap[SGV] = DGA;
- } else
+ continue;
+ }
+
+ if (LinkFromSrc) {
+ if (isa<GlobalAlias>(DGV))
+ return Error(Err, "Global-Alias Collision on '" + SGV->getName() +
+ "': symbol multiple defined");
+
+ // If the types don't match, and if we are to link from the source, nuke
+ // DGV and create a new one of the appropriate type. Note that the thing
+ // we are replacing may be a function (if a prototype, weak, etc) or a
+ // global variable.
+ GlobalVariable *NewDGV =
+ new GlobalVariable(SGV->getType()->getElementType(), SGV->isConstant(),
+ NewLinkage, /*init*/0, DGV->getName(), Dest, false,
+ SGV->getType()->getAddressSpace());
+
+ // Propagate alignment, section, and visibility info.
+ CopyGVAttributes(NewDGV, SGV);
+ DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewDGV, DGV->getType()));
+
+ // DGV will conflict with NewDGV because they both had the same
+ // name. We must erase this now so ForceRenaming doesn't assert
+ // because DGV might not have internal linkage.
+ if (GlobalVariable *Var = dyn_cast<GlobalVariable>(DGV))
+ Var->eraseFromParent();
+ else
+ cast<Function>(DGV)->eraseFromParent();
+ DGV = NewDGV;
+
+ // If the symbol table renamed the global, but it is an externally visible
+ // symbol, DGV must be an existing global with internal linkage. Rename.
+ if (NewDGV->getName() != SGV->getName() && !NewDGV->hasLocalLinkage())
+ ForceRenaming(NewDGV, SGV->getName());
+
+ // Inherit const as appropriate.
+ NewDGV->setConstant(SGV->isConstant());
+
+ // Make sure to remember this mapping.
+ ValueMap[SGV] = NewDGV;
+ continue;
+ }
+
+ // Not "link from source", keep the one in the DestModule and remap the
+ // input onto it.
+
+ // Special case for const propagation.
+ if (GlobalVariable *DGVar = dyn_cast<GlobalVariable>(DGV))
+ if (DGVar->isDeclaration() && SGV->isConstant() && !DGVar->isConstant())
+ DGVar->setConstant(true);
+
+ // SGV is global, but DGV is alias.
+ if (isa<GlobalAlias>(DGV)) {
+ // The only valid mappings are:
+ // - SGV is external declaration, which is effectively a no-op.
+ // - SGV is weak, when we just need to throw SGV out.
+ if (!SGV->isDeclaration() && !SGV->mayBeOverridden())
return Error(Err, "Global-Alias Collision on '" + SGV->getName() +
"': symbol multiple defined");
- } else if (GlobalVariable *DGVar = dyn_cast<GlobalVariable>(DGV)) {
- // Otherwise, perform the global-global mapping as instructed by
- // GetLinkageResult.
- if (LinkFromSrc) {
- // Propagate alignment, section, and visibility info.
- CopyGVAttributes(DGVar, SGV);
-
- // If the types don't match, and if we are to link from the source, nuke
- // DGV and create a new one of the appropriate type.
- if (SGV->getType() != DGVar->getType()) {
- GlobalVariable *NewDGV =
- new GlobalVariable(SGV->getType()->getElementType(),
- DGVar->isConstant(), DGVar->getLinkage(),
- /*init*/0, DGVar->getName(), Dest);
- CopyGVAttributes(NewDGV, DGVar);
- DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewDGV,
- DGVar->getType()));
- // DGVar will conflict with NewDGV because they both had the same
- // name. We must erase this now so ForceRenaming doesn't assert
- // because DGV might not have internal linkage.
- DGVar->eraseFromParent();
-
- // If the symbol table renamed the global, but it is an externally
- // visible symbol, DGV must be an existing global with internal
- // linkage. Rename it.
- if (NewDGV->getName() != SGV->getName() &&
- !NewDGV->hasInternalLinkage())
- ForceRenaming(NewDGV, SGV->getName());
-
- DGVar = NewDGV;
- }
-
- // Inherit const as appropriate
- DGVar->setConstant(SGV->isConstant());
-
- // Set initializer to zero, so we can link the stuff later
- DGVar->setInitializer(0);
- } else {
- // Special case for const propagation
- if (DGVar->isDeclaration() && SGV->isConstant() && !DGVar->isConstant())
- DGVar->setConstant(true);
- }
-
- // Set calculated linkage
- DGVar->setLinkage(NewLinkage);
-
- // Make sure to remember this mapping...
- ValueMap[SGV] = ConstantExpr::getBitCast(DGVar, SGV->getType());
}
+
+ // Set calculated linkage
+ DGV->setLinkage(NewLinkage);
+
+ // Make sure to remember this mapping...
+ ValueMap[SGV] = ConstantExpr::getBitCast(DGV, SGV->getType());
}
return false;
}
return GlobalValue::ExternalLinkage;
else if (SGV->hasWeakLinkage() || DGV->hasWeakLinkage())
return GlobalValue::WeakLinkage;
- else {
- assert(SGV->hasInternalLinkage() && DGV->hasInternalLinkage() &&
- "Unexpected linkage type");
+ else if (SGV->hasInternalLinkage() && DGV->hasInternalLinkage())
return GlobalValue::InternalLinkage;
+ else {
+ assert (SGV->hasPrivateLinkage() && DGV->hasPrivateLinkage() &&
+ "Unexpected linkage type");
+ return GlobalValue::PrivateLinkage;
}
}
GlobalValue* DGV = NULL;
// Try to find something 'similar' to SGA in destination module.
- if (!DGV && !SGA->hasInternalLinkage()) {
+ if (!DGV && !SGA->hasLocalLinkage()) {
DGV = Dest->getNamedAlias(SGA->getName());
// If types don't agree due to opaque types, try to resolve them.
if (DGV && DGV->getType() != SGA->getType())
- if (RecursiveResolveTypes(SGA->getType(), DGV->getType()))
- return Error(Err, "Alias Collision on '" + SGA->getName()+
- "': aliases have different types");
+ RecursiveResolveTypes(SGA->getType(), DGV->getType());
}
- if (!DGV && !SGA->hasInternalLinkage()) {
+ if (!DGV && !SGA->hasLocalLinkage()) {
DGV = Dest->getGlobalVariable(SGA->getName());
// If types don't agree due to opaque types, try to resolve them.
if (DGV && DGV->getType() != SGA->getType())
- if (RecursiveResolveTypes(SGA->getType(), DGV->getType()))
- return Error(Err, "Alias Collision on '" + SGA->getName()+
- "': aliases have different types");
+ RecursiveResolveTypes(SGA->getType(), DGV->getType());
}
- if (!DGV && !SGA->hasInternalLinkage()) {
+ if (!DGV && !SGA->hasLocalLinkage()) {
DGV = Dest->getFunction(SGA->getName());
// If types don't agree due to opaque types, try to resolve them.
if (DGV && DGV->getType() != SGA->getType())
- if (RecursiveResolveTypes(SGA->getType(), DGV->getType()))
- return Error(Err, "Alias Collision on '" + SGA->getName()+
- "': aliases have different types");
+ RecursiveResolveTypes(SGA->getType(), DGV->getType());
}
// No linking to be performed on internal stuff.
- if (DGV && DGV->hasInternalLinkage())
+ if (DGV && DGV->hasLocalLinkage())
DGV = NULL;
if (GlobalAlias *DGA = dyn_cast_or_null<GlobalAlias>(DGV)) {
return Error(Err, "Alias Collision on '" + SGA->getName()+
"': aliases have different aliasees");
} else if (GlobalVariable *DGVar = dyn_cast_or_null<GlobalVariable>(DGV)) {
- // The only allowed way is to link alias with external declaration.
- if (DGVar->isDeclaration()) {
+ // The only allowed way is to link alias with external declaration or weak
+ // symbol..
+ if (DGVar->isDeclaration() || DGVar->mayBeOverridden()) {
// But only if aliasee is global too...
if (!isa<GlobalVariable>(DAliasee))
return Error(Err, "Global-Alias Collision on '" + SGA->getName() +
return Error(Err, "Global-Alias Collision on '" + SGA->getName() +
"': symbol multiple defined");
} else if (Function *DF = dyn_cast_or_null<Function>(DGV)) {
- // The only allowed way is to link alias with external declaration.
- if (DF->isDeclaration()) {
+ // The only allowed way is to link alias with external declaration or weak
+ // symbol...
+ if (DF->isDeclaration() || DF->mayBeOverridden()) {
// But only if aliasee is function too...
if (!isa<Function>(DAliasee))
return Error(Err, "Function-Alias Collision on '" + SGA->getName() +
// If the symbol table renamed the alias, but it is an externally visible
// symbol, DGA must be an global value with internal linkage. Rename it.
if (NewGA->getName() != SGA->getName() &&
- !NewGA->hasInternalLinkage())
+ !NewGA->hasLocalLinkage())
ForceRenaming(NewGA, SGA->getName());
// Remember this mapping so uses in the source module get remapped
static bool LinkGlobalInits(Module *Dest, const Module *Src,
std::map<const Value*, Value*> &ValueMap,
std::string *Err) {
-
// Loop over all of the globals in the src module, mapping them over as we go
for (Module::const_global_iterator I = Src->global_begin(),
E = Src->global_end(); I != E; ++I) {
// Figure out what the initializer looks like in the dest module...
Constant *SInit =
cast<Constant>(RemapOperand(SGV->getInitializer(), ValueMap));
-
- GlobalVariable *DGV =
- cast<GlobalVariable>(ValueMap[SGV]->stripPointerCasts());
- if (DGV->hasInitializer()) {
- if (SGV->hasExternalLinkage()) {
- if (DGV->getInitializer() != SInit)
- return Error(Err, "Global Variable Collision on '" + SGV->getName() +
- "': global variables have different initializers");
- } else if (DGV->hasLinkOnceLinkage() || DGV->hasWeakLinkage() ||
- DGV->hasCommonLinkage()) {
- // Nothing is required, mapped values will take the new global
- // automatically.
- } else if (SGV->hasLinkOnceLinkage() || SGV->hasWeakLinkage() ||
- SGV->hasCommonLinkage()) {
- // Nothing is required, mapped values will take the new global
- // automatically.
- } else if (DGV->hasAppendingLinkage()) {
- assert(0 && "Appending linkage unimplemented!");
+ // Grab destination global variable or alias.
+ GlobalValue *DGV = cast<GlobalValue>(ValueMap[SGV]->stripPointerCasts());
+
+ // If dest if global variable, check that initializers match.
+ if (GlobalVariable *DGVar = dyn_cast<GlobalVariable>(DGV)) {
+ if (DGVar->hasInitializer()) {
+ if (SGV->hasExternalLinkage()) {
+ if (DGVar->getInitializer() != SInit)
+ return Error(Err, "Global Variable Collision on '" +
+ SGV->getName() +
+ "': global variables have different initializers");
+ } else if (DGVar->mayBeOverridden()) {
+ // Nothing is required, mapped values will take the new global
+ // automatically.
+ } else if (SGV->mayBeOverridden()) {
+ // Nothing is required, mapped values will take the new global
+ // automatically.
+ } else if (DGVar->hasAppendingLinkage()) {
+ assert(0 && "Appending linkage unimplemented!");
+ } else {
+ assert(0 && "Unknown linkage!");
+ }
} else {
- assert(0 && "Unknown linkage!");
+ // Copy the initializer over now...
+ DGVar->setInitializer(SInit);
}
} else {
- // Copy the initializer over now...
- DGV->setInitializer(SInit);
+ // Destination is alias, the only valid situation is when source is
+ // weak. Also, note, that we already checked linkage in LinkGlobals(),
+ // thus we assert here.
+ // FIXME: Should we weaken this assumption, 'dereference' alias and
+ // check for initializer of aliasee?
+ assert(SGV->mayBeOverridden());
}
}
}
static bool LinkFunctionProtos(Module *Dest, const Module *Src,
std::map<const Value*, Value*> &ValueMap,
std::string *Err) {
+ ValueSymbolTable &DestSymTab = Dest->getValueSymbolTable();
+
// Loop over all of the functions in the src module, mapping them over
for (Module::const_iterator I = Src->begin(), E = Src->end(); I != E; ++I) {
const Function *SF = I; // SrcFunction
+ GlobalValue *DGV = 0;
- Function *DF = 0;
+ // Check to see if may have to link the function with the global, alias or
+ // function.
+ if (SF->hasName() && !SF->hasLocalLinkage())
+ DGV = cast_or_null<GlobalValue>(DestSymTab.lookup(SF->getNameStart(),
+ SF->getNameEnd()));
- // If this function is internal or has no name, it doesn't participate in
- // linkage.
- if (SF->hasName() && !SF->hasInternalLinkage()) {
- // Check to see if may have to link the function.
- DF = Dest->getFunction(SF->getName());
- if (DF && DF->hasInternalLinkage())
- DF = 0;
- }
+ // 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 && DGV->hasLocalLinkage())
+ DGV = 0;
+
+ // If types don't agree due to opaque types, try to resolve them.
+ if (DGV && DGV->getType() != SF->getType())
+ RecursiveResolveTypes(SF->getType(), DGV->getType());
+
+ GlobalValue::LinkageTypes NewLinkage = GlobalValue::InternalLinkage;
+ bool LinkFromSrc = false;
+ if (GetLinkageResult(DGV, SF, NewLinkage, LinkFromSrc, Err))
+ return true;
// If there is no linkage to be performed, just bring over SF without
// modifying it.
- if (DF == 0) {
+ if (DGV == 0) {
// Function does not already exist, simply insert an function signature
// identical to SF into the dest module.
Function *NewDF = Function::Create(SF->getFunctionType(),
// If the LLVM runtime renamed the function, but it is an externally
// visible symbol, DF must be an existing function with internal linkage.
// Rename it.
- if (!NewDF->hasInternalLinkage() && NewDF->getName() != SF->getName())
+ if (!NewDF->hasLocalLinkage() && NewDF->getName() != SF->getName())
ForceRenaming(NewDF, SF->getName());
// ... and remember this mapping...
continue;
}
+ // If the visibilities of the symbols disagree and the destination is a
+ // prototype, take the visibility of its input.
+ if (DGV->isDeclaration())
+ DGV->setVisibility(SF->getVisibility());
- // If types don't agree because of opaque, try to resolve them.
- if (SF->getType() != DF->getType())
- RecursiveResolveTypes(SF->getType(), DF->getType());
-
- // Check visibility, merging if a definition overrides a prototype.
- if (SF->getVisibility() != DF->getVisibility()) {
- // If one is a prototype, ignore its visibility. Prototypes are always
- // overridden by the definition.
- if (!SF->isDeclaration() && !DF->isDeclaration())
- return Error(Err, "Linking functions named '" + SF->getName() +
- "': symbols have different visibilities!");
+ if (LinkFromSrc) {
+ if (isa<GlobalAlias>(DGV))
+ return Error(Err, "Function-Alias Collision on '" + SF->getName() +
+ "': symbol multiple defined");
- // Otherwise, replace the visibility of DF if DF is a prototype.
- if (DF->isDeclaration())
- DF->setVisibility(SF->getVisibility());
- }
-
- if (DF->getType() != SF->getType()) {
- if (DF->isDeclaration() && !SF->isDeclaration()) {
- // We have a definition of the same name but different type in the
- // source module. Copy the prototype to the destination and replace
- // uses of the destination's prototype with the new prototype.
- Function *NewDF = Function::Create(SF->getFunctionType(),
- SF->getLinkage(),
- SF->getName(), Dest);
- CopyGVAttributes(NewDF, SF);
-
- // Any uses of DF need to change to NewDF, with cast
- DF->replaceAllUsesWith(ConstantExpr::getBitCast(NewDF, DF->getType()));
-
- // DF will conflict with NewDF because they both had the same. We must
- // erase this now so ForceRenaming doesn't assert because DF might
- // not have internal linkage.
- DF->eraseFromParent();
-
- // If the symbol table renamed the function, but it is an externally
- // visible symbol, DF must be an existing function with internal
- // linkage. Rename it.
- if (NewDF->getName() != SF->getName() && !NewDF->hasInternalLinkage())
- ForceRenaming(NewDF, SF->getName());
-
- // Remember this mapping so uses in the source module get remapped
- // later by RemapOperand.
- ValueMap[SF] = NewDF;
- } else if (SF->isDeclaration()) {
- // We have two functions of the same name but different type and the
- // source is a declaration while the destination is not. Any use of
- // the source must be mapped to the destination, with a cast.
- ValueMap[SF] = ConstantExpr::getBitCast(DF, SF->getType());
- } else {
- // We have two functions of the same name but different types and they
- // are both definitions. This is an error.
- return Error(Err, "Function '" + DF->getName() + "' defined as both '" +
- ToStr(SF->getFunctionType(), Src) + "' and '" +
- ToStr(DF->getFunctionType(), Dest) + "'");
- }
- continue;
- }
-
- if (SF->isDeclaration()) {
- // If SF is a declaration or if both SF & DF are declarations, just link
- // the declarations, we aren't adding anything.
- if (SF->hasDLLImportLinkage()) {
- if (DF->isDeclaration()) {
- ValueMap[SF] = DF;
- DF->setLinkage(SF->getLinkage());
- }
- } else {
- ValueMap[SF] = DF;
- }
- continue;
- }
-
- // If DF is external but SF is not, link the external functions, update
- // linkage qualifiers.
- if (DF->isDeclaration() && !DF->hasDLLImportLinkage()) {
- ValueMap.insert(std::make_pair(SF, DF));
- DF->setLinkage(SF->getLinkage());
+ // We have a definition of the same name but different type in the
+ // source module. Copy the prototype to the destination and replace
+ // uses of the destination's prototype with the new prototype.
+ Function *NewDF = Function::Create(SF->getFunctionType(), NewLinkage,
+ SF->getName(), Dest);
+ CopyGVAttributes(NewDF, SF);
+
+ // Any uses of DF need to change to NewDF, with cast
+ DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewDF, DGV->getType()));
+
+ // DF will conflict with NewDF because they both had the same. We must
+ // erase this now so ForceRenaming doesn't assert because DF might
+ // not have internal linkage.
+ if (GlobalVariable *Var = dyn_cast<GlobalVariable>(DGV))
+ Var->eraseFromParent();
+ else
+ cast<Function>(DGV)->eraseFromParent();
+
+ // If the symbol table renamed the function, but it is an externally
+ // visible symbol, DF must be an existing function with internal
+ // linkage. Rename it.
+ if (NewDF->getName() != SF->getName() && !NewDF->hasLocalLinkage())
+ ForceRenaming(NewDF, SF->getName());
+
+ // Remember this mapping so uses in the source module get remapped
+ // later by RemapOperand.
+ ValueMap[SF] = NewDF;
continue;
}
- // At this point we know that DF has LinkOnce, Weak, or External* linkage.
- if (SF->hasWeakLinkage() || SF->hasLinkOnceLinkage() ||
- SF->hasCommonLinkage()) {
- ValueMap[SF] = DF;
-
- // Linkonce+Weak = Weak
- // *+External Weak = *
- if ((DF->hasLinkOnceLinkage() &&
- (SF->hasWeakLinkage() || SF->hasCommonLinkage())) ||
- DF->hasExternalWeakLinkage())
- DF->setLinkage(SF->getLinkage());
- continue;
- }
+ // Not "link from source", keep the one in the DestModule and remap the
+ // input onto it.
- if (DF->hasWeakLinkage() || DF->hasLinkOnceLinkage() ||
- DF->hasCommonLinkage()) {
- // At this point we know that SF has LinkOnce or External* linkage.
- ValueMap[SF] = DF;
-
- // If the source function has stronger linkage than the destination,
- // its body and linkage should override ours.
- if (!SF->hasLinkOnceLinkage() && !SF->hasExternalWeakLinkage()) {
- // Don't inherit linkonce & external weak linkage.
- DF->setLinkage(SF->getLinkage());
- DF->deleteBody();
- }
- continue;
+ if (isa<GlobalAlias>(DGV)) {
+ // The only valid mappings are:
+ // - SF is external declaration, which is effectively a no-op.
+ // - SF is weak, when we just need to throw SF out.
+ if (!SF->isDeclaration() && !SF->mayBeOverridden())
+ return Error(Err, "Function-Alias Collision on '" + SF->getName() +
+ "': symbol multiple defined");
}
-
- if (SF->getLinkage() != DF->getLinkage())
- return Error(Err, "Functions named '" + SF->getName() +
- "' have different linkage specifiers!");
-
- // The function is defined identically in both modules!
- if (SF->hasExternalLinkage())
- return Error(Err, "Function '" +
- ToStr(SF->getFunctionType(), Src) + "':\"" +
- SF->getName() + "\" - Function is already defined!");
- assert(0 && "Unknown linkage configuration found!");
+
+ // Set calculated linkage
+ DGV->setLinkage(NewLinkage);
+
+ // Make sure to remember this mapping.
+ ValueMap[SF] = ConstantExpr::getBitCast(DGV, SF->getType());
}
return false;
}
// go
for (Module::iterator SF = Src->begin(), E = Src->end(); SF != E; ++SF) {
if (!SF->isDeclaration()) { // No body if function is external
- Function *DF = cast<Function>(ValueMap[SF]); // Destination function
+ Function *DF = dyn_cast<Function>(ValueMap[SF]); // Destination function
// DF not external SF external?
- if (DF->isDeclaration())
+ if (DF && DF->isDeclaration())
// Only provide the function body if there isn't one already.
if (LinkFunctionBody(DF, SF, ValueMap, Err))
return true;
// Create the new global variable...
GlobalVariable *NG =
new GlobalVariable(NewType, G1->isConstant(), G1->getLinkage(),
- /*init*/0, First->first, M, G1->isThreadLocal());
+ /*init*/0, First->first, M, G1->isThreadLocal(),
+ G1->getType()->getAddressSpace());
// Propagate alignment, visibility and section info.
CopyGVAttributes(NG, G1);
for (Module::alias_iterator I = Dest->alias_begin(), E = Dest->alias_end();
I != E; ++I)
if (const GlobalValue *GV = I->resolveAliasedGlobal())
- if (!GV->isDeclaration())
+ if (GV != I && !GV->isDeclaration())
I->replaceAllUsesWith(const_cast<GlobalValue*>(GV));
return false;
projects / oota-llvm.git / blobdiff