X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FLinker%2FLinkModules.cpp;h=1609c6c0e094c7435f11d7f398630d500218a75d;hb=73b43b9b549a75fb0015c825df68abd95705a67c;hp=33da6684575407d76e3e7edd93eda49b17fd95eb;hpb=01f69399352380532d480f6749daed660f50b15c;p=oota-llvm.git diff --git a/lib/Linker/LinkModules.cpp b/lib/Linker/LinkModules.cpp index 33da6684575..1609c6c0e09 100644 --- a/lib/Linker/LinkModules.cpp +++ b/lib/Linker/LinkModules.cpp @@ -26,6 +26,7 @@ #include "llvm/Assembly/Writer.h" #include "llvm/Support/Streams.h" #include "llvm/System/Path.h" +#include "llvm/ADT/DenseMap.h" #include using namespace llvm; @@ -52,7 +53,6 @@ static std::string ToStr(const Type *Ty, const Module *M) { // Inputs: // DestTy - The type to which we wish to resolve. // SrcTy - The original type which we want to resolve. -// Name - The name of the type. // // Outputs: // DestST - The symbol table in which the new type should be placed. @@ -61,121 +61,203 @@ static std::string ToStr(const Type *Ty, const Module *M) { // true - There is an error and the types cannot yet be linked. // false - No errors. // -static bool ResolveTypes(const Type *DestTy, const Type *SrcTy, - TypeSymbolTable *DestST, const std::string &Name) { +static bool ResolveTypes(const Type *DestTy, const Type *SrcTy) { if (DestTy == SrcTy) return false; // If already equal, noop + assert(DestTy && SrcTy && "Can't handle null types"); - // Does the type already exist in the module? - if (DestTy && !isa(DestTy)) { // Yup, the type already exists... - if (const OpaqueType *OT = dyn_cast(SrcTy)) { - const_cast(OT)->refineAbstractTypeTo(DestTy); - } else { - return true; // Cannot link types... neither is opaque and not-equal - } - } else { // Type not in dest module. Add it now. - if (DestTy) // Type _is_ in module, just opaque... - const_cast(cast(DestTy)) - ->refineAbstractTypeTo(SrcTy); - else if (!Name.empty()) - DestST->insert(Name, const_cast(SrcTy)); + if (const OpaqueType *OT = dyn_cast(DestTy)) { + // Type _is_ in module, just opaque... + const_cast(OT)->refineAbstractTypeTo(SrcTy); + } else if (const OpaqueType *OT = dyn_cast(SrcTy)) { + const_cast(OT)->refineAbstractTypeTo(DestTy); + } else { + return true; // Cannot link types... not-equal and neither is opaque. } return false; } -static const FunctionType *getFT(const PATypeHolder &TH) { - return cast(TH.get()); -} -static const StructType *getST(const PATypeHolder &TH) { - return cast(TH.get()); +/// 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 TheMapTy; + TheMapTy TheMap; + + LinkerTypeMap(const LinkerTypeMap&); // DO NOT IMPLEMENT + void operator=(const LinkerTypeMap&); // DO NOT IMPLEMENT +public: + LinkerTypeMap() {} + ~LinkerTypeMap() { + for (DenseMap::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)))) + 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, - TypeSymbolTable *DestST, - const std::string &Name, - std::vector > &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(DestTyT) || isa(SrcTyT)) - return ResolveTypes(DestTyT, SrcTyT, DestST, Name); + if (isa(DstTy) || isa(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()) { - case Type::IntegerTyID: { - if (cast(DestTyT)->getBitWidth() != - cast(SrcTyT)->getBitWidth()) - return true; - return false; - } + switch (DstTy->getTypeID()) { + default: + return true; case Type::FunctionTyID: { - if (cast(DestTyT)->isVarArg() != - cast(SrcTyT)->isVarArg() || - cast(DestTyT)->getNumContainedTypes() != - cast(SrcTyT)->getNumContainedTypes()) + const FunctionType *DstFT = cast(DstTy); + const FunctionType *SrcFT = cast(SrcTy); + if (DstFT->isVarArg() != SrcFT->isVarArg() || + DstFT->getNumContainedTypes() != SrcFT->getNumContainedTypes()) return true; - for (unsigned i = 0, e = getFT(DestTy)->getNumContainedTypes(); i != e; ++i) - if (RecursiveResolveTypesI(getFT(DestTy)->getContainedType(i), - getFT(SrcTy)->getContainedType(i), DestST, "", - 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: { - if (getST(DestTy)->getNumContainedTypes() != - getST(SrcTy)->getNumContainedTypes()) return 1; - for (unsigned i = 0, e = getST(DestTy)->getNumContainedTypes(); i != e; ++i) - if (RecursiveResolveTypesI(getST(DestTy)->getContainedType(i), - getST(SrcTy)->getContainedType(i), DestST, "", - Pointers)) + const StructType *DstST = cast(DstTy); + const StructType *SrcST = cast(SrcTy); + if (DstST->getNumContainedTypes() != SrcST->getNumContainedTypes()) + return true; + + 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(DestTy.get()); - const ArrayType *SAT = cast(SrcTy.get()); + const ArrayType *DAT = cast(DstTy); + const ArrayType *SAT = cast(SrcTy); if (DAT->getNumElements() != SAT->getNumElements()) return true; return RecursiveResolveTypesI(DAT->getElementType(), SAT->getElementType(), - DestST, "", Pointers); + Pointers); + } + case Type::VectorTyID: { + const VectorType *DVT = cast(DstTy); + const VectorType *SVT = cast(SrcTy); + if (DVT->getNumElements() != SVT->getNumElements()) return true; + return RecursiveResolveTypesI(DVT->getElementType(), SVT->getElementType(), + Pointers); } case Type::PointerTyID: { + const PointerType *DstPT = cast(DstTy); + const PointerType *SrcPT = cast(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)); - bool Result = - RecursiveResolveTypesI(cast(DestTy.get())->getElementType(), - cast(SrcTy.get())->getElementType(), - DestST, "", Pointers); - Pointers.pop_back(); - return Result; + if (DstPT->isAbstract()) + Pointers.insert(DstPT, SrcPT); + if (SrcPT->isAbstract()) + Pointers.insert(SrcPT, DstPT); + + return RecursiveResolveTypesI(DstPT->getElementType(), + SrcPT->getElementType(), Pointers); } - default: assert(0 && "Unexpected type!"); return true; } } -static bool RecursiveResolveTypes(const PATypeHolder &DestTy, - const PATypeHolder &SrcTy, - TypeSymbolTable *DestST, - const std::string &Name){ - std::vector > PointerTypes; - return RecursiveResolveTypesI(DestTy, SrcTy, DestST, Name, PointerTypes); +static bool RecursiveResolveTypes(const Type *DestTy, const Type *SrcTy) { + LinkerTypeMap PointerTypes; + return RecursiveResolveTypesI(DestTy, SrcTy, PointerTypes); } @@ -200,10 +282,14 @@ static bool LinkTypes(Module *Dest, const Module *Src, std::string *Err) { const std::string &Name = TI->first; const Type *RHS = TI->second; - // Check to see if this type name is already in the dest module... + // Check to see if this type name is already in the dest module. Type *Entry = DestST->lookup(Name); - if (ResolveTypes(Entry, RHS, DestST, Name)) { + // If the name is just in the source module, bring it over to the dest. + if (Entry == 0) { + if (!Name.empty()) + DestST->insert(Name, const_cast(RHS)); + } else if (ResolveTypes(Entry, RHS)) { // They look different, save the types 'till later to resolve. DelayedTypesToResolve.push_back(Name); } @@ -219,7 +305,7 @@ static bool LinkTypes(Module *Dest, const Module *Src, std::string *Err) { const std::string &Name = DelayedTypesToResolve[i]; Type *T1 = SrcST->lookup(Name); Type *T2 = DestST->lookup(Name); - if (!ResolveTypes(T2, T1, DestST, Name)) { + if (!ResolveTypes(T2, T1)) { // We are making progress! DelayedTypesToResolve.erase(DelayedTypesToResolve.begin()+i); --i; @@ -232,10 +318,7 @@ static bool LinkTypes(Module *Dest, const Module *Src, std::string *Err) { // 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, DestST, Name)) { + if (!RecursiveResolveTypes(SrcST->lookup(Name), DestST->lookup(Name))) { // We are making progress! DelayedTypesToResolve.erase(DelayedTypesToResolve.begin()+i); @@ -316,7 +399,7 @@ static Value *RemapOperand(const Value *In, // Cache the mapping in our local map structure if (Result) { - ValueMap.insert(std::make_pair(In, Result)); + ValueMap[In] = Result; return Result; } @@ -351,20 +434,10 @@ static void ForceRenaming(GlobalValue *GV, const std::string &Name) { /// CopyGVAttributes - copy additional attributes (those not needed to construct /// a GlobalValue) from the SrcGV to the DestGV. static void CopyGVAttributes(GlobalValue *DestGV, const GlobalValue *SrcGV) { - // Propagate alignment, visibility and section info. - DestGV->setAlignment(std::max(DestGV->getAlignment(), SrcGV->getAlignment())); - DestGV->setSection(SrcGV->getSection()); - DestGV->setVisibility(SrcGV->getVisibility()); - if (const Function *SrcF = dyn_cast(SrcGV)) { - Function *DestF = cast(DestGV); - DestF->setCallingConv(SrcF->getCallingConv()); - DestF->setParamAttrs(SrcF->getParamAttrs()); - if (SrcF->hasCollector()) - DestF->setCollector(SrcF->getCollector()); - } else if (const GlobalVariable *SrcVar = dyn_cast(SrcGV)) { - GlobalVariable *DestVar = cast(DestGV); - DestVar->setThreadLocal(SrcVar->isThreadLocal()); - } + // Use the maximum alignment, rather than just copying the alignment of SrcGV. + unsigned Alignment = std::max(DestGV->getAlignment(), SrcGV->getAlignment()); + DestGV->copyAttributesFrom(SrcGV); + DestGV->setAlignment(Alignment); } /// GetLinkageResult - This analyzes the two global values and determines what @@ -410,10 +483,12 @@ static bool GetLinkageResult(GlobalValue *Dest, const GlobalValue *Src, "': can only link appending global with another appending global!"); LinkFromSrc = true; // Special cased. LT = Src->getLinkage(); - } else if (Src->hasWeakLinkage() || Src->hasLinkOnceLinkage()) { - // At this point we know that Dest has LinkOnce, External*, Weak, or - // DLL* linkage. - if ((Dest->hasLinkOnceLinkage() && Src->hasWeakLinkage()) || + } else if (Src->hasWeakLinkage() || Src->hasLinkOnceLinkage() || + Src->hasCommonLinkage()) { + // At this point we know that Dest has LinkOnce, External*, Weak, Common, + // or DLL* linkage. + if ((Dest->hasLinkOnceLinkage() && + (Src->hasWeakLinkage() || Src->hasCommonLinkage())) || Dest->hasExternalWeakLinkage()) { LinkFromSrc = true; LT = Src->getLinkage(); @@ -421,7 +496,8 @@ static bool GetLinkageResult(GlobalValue *Dest, const GlobalValue *Src, LinkFromSrc = false; LT = Dest->getLinkage(); } - } else if (Dest->hasWeakLinkage() || Dest->hasLinkOnceLinkage()) { + } else if (Dest->hasWeakLinkage() || Dest->hasLinkOnceLinkage() || + Dest->hasCommonLinkage()) { // At this point we know that Src has External* or DLL* linkage. if (Src->hasExternalWeakLinkage()) { LinkFromSrc = false; @@ -469,17 +545,15 @@ static bool LinkGlobals(Module *Dest, const Module *Src, 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(), - &Dest->getTypeSymbolTable(), ""); + RecursiveResolveTypes(SGV->getType(), DGV->getType()); } // Check to see if may have to link the global with the alias - if (SGV->hasName() && !SGV->hasInternalLinkage()) { + 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(), - &Dest->getTypeSymbolTable(), ""); + RecursiveResolveTypes(SGV->getType(), DGV->getType()); } if (DGV && DGV->hasInternalLinkage()) @@ -512,7 +586,8 @@ static bool LinkGlobals(Module *Dest, const Module *Src, ForceRenaming(NewDGV, SGV->getName()); // Make sure to remember this mapping... - ValueMap.insert(std::make_pair(SGV, NewDGV)); + ValueMap[SGV] = NewDGV; + if (SGV->hasAppendingLinkage()) // Keep track that this is an appending variable... AppendingVars.insert(std::make_pair(SGV->getName(), NewDGV)); @@ -532,23 +607,23 @@ static bool LinkGlobals(Module *Dest, const Module *Src, CopyGVAttributes(NewDGV, SGV); // Make sure to remember this mapping... - ValueMap.insert(std::make_pair(SGV, NewDGV)); + ValueMap[SGV] = NewDGV; // Keep track that this is an appending variable... AppendingVars.insert(std::make_pair(SGV->getName(), NewDGV)); } else if (GlobalAlias *DGA = dyn_cast(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 is correct. + // linkage calculation was correct. if (SGV->isDeclaration() && !LinkFromSrc) { // Make sure to remember this mapping... - ValueMap.insert(std::make_pair(SGV, DGA)); + ValueMap[SGV] = DGA; } else - return Error(Err, "Global-Alias Collision on '" + - ToStr(SGV->getType(), Src) +"':%"+SGV->getName()+ - " - symbol multiple defined"); + return Error(Err, "Global-Alias Collision on '" + SGV->getName() + + "': symbol multiple defined"); } else if (GlobalVariable *DGVar = dyn_cast(DGV)) { - // Otherwise, perform the mapping as instructed by GetLinkageResult. + // Otherwise, perform the global-global mapping as instructed by + // GetLinkageResult. if (LinkFromSrc) { // Propagate alignment, section, and visibility info. CopyGVAttributes(DGVar, SGV); @@ -593,9 +668,7 @@ static bool LinkGlobals(Module *Dest, const Module *Src, DGVar->setLinkage(NewLinkage); // Make sure to remember this mapping... - ValueMap.insert(std::make_pair(SGV, - ConstantExpr::getBitCast(DGVar, - SGV->getType()))); + ValueMap[SGV] = ConstantExpr::getBitCast(DGVar, SGV->getType()); } } return false; @@ -628,21 +701,49 @@ static bool LinkAlias(Module *Dest, const Module *Src, GlobalAlias *NewGA = NULL; // Globals were already linked, thus we can just query ValueMap for variant - // of SAliasee in Dest + // of SAliasee in Dest. std::map::const_iterator VMI = ValueMap.find(SAliasee); assert(VMI != ValueMap.end() && "Aliasee not linked"); GlobalValue* DAliasee = cast(VMI->second); + GlobalValue* DGV = NULL; // Try to find something 'similar' to SGA in destination module. - if (GlobalAlias *DGA = Dest->getNamedAlias(SGA->getName())) { + if (!DGV && !SGA->hasInternalLinkage()) { + 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"); + } + + if (!DGV && !SGA->hasInternalLinkage()) { + 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"); + } + + if (!DGV && !SGA->hasInternalLinkage()) { + DGV = Dest->getFunction(SGA->getName()); + // If types don't agree due to opaque types, try to resolve them. - if (RecursiveResolveTypes(SGA->getType(), DGA->getType(), - &Dest->getTypeSymbolTable(), "")) - return Error(Err, "Alias Collision on '" + - ToStr(SGA->getType(), Src) +"':%"+SGA->getName()+ - " - aliases have different types"); + if (DGV && DGV->getType() != SGA->getType()) + if (RecursiveResolveTypes(SGA->getType(), DGV->getType())) + return Error(Err, "Alias Collision on '" + SGA->getName()+ + "': aliases have different types"); + } - // Now types are known to be the same, check whether aliasees equal. As + // No linking to be performed on internal stuff. + if (DGV && DGV->hasInternalLinkage()) + DGV = NULL; + + if (GlobalAlias *DGA = dyn_cast_or_null(DGV)) { + // Types are known to be the same, check whether aliasees equal. As // globals are already linked we just need query ValueMap to find the // mapping. if (DAliasee == DGA->getAliasedGlobal()) { @@ -653,42 +754,44 @@ static bool LinkAlias(Module *Dest, const Module *Src, NewGA = DGA; // Proceed to 'common' steps } else - return Error(Err, "Alias Collision on '" + - ToStr(SGA->getType(), Src) +"':%"+SGA->getName()+ - " - aliases have different aliasees"); - } else if (GlobalVariable *DGV = Dest->getGlobalVariable(SGA->getName())) { - RecursiveResolveTypes(SGA->getType(), DGV->getType(), - &Dest->getTypeSymbolTable(), ""); - + return Error(Err, "Alias Collision on '" + SGA->getName()+ + "': aliases have different aliasees"); + } else if (GlobalVariable *DGVar = dyn_cast_or_null(DGV)) { // The only allowed way is to link alias with external declaration. - if (DGV->isDeclaration()) { + if (DGVar->isDeclaration()) { + // But only if aliasee is global too... + if (!isa(DAliasee)) + return Error(Err, "Global-Alias Collision on '" + SGA->getName() + + "': aliasee is not global variable"); + NewGA = new GlobalAlias(SGA->getType(), SGA->getLinkage(), SGA->getName(), DAliasee, Dest); CopyGVAttributes(NewGA, SGA); // Any uses of DGV need to change to NewGA, with cast, if needed. - if (SGA->getType() != DGV->getType()) - DGV->replaceAllUsesWith(ConstantExpr::getBitCast(NewGA, - DGV->getType())); + if (SGA->getType() != DGVar->getType()) + DGVar->replaceAllUsesWith(ConstantExpr::getBitCast(NewGA, + DGVar->getType())); else - DGV->replaceAllUsesWith(NewGA); + DGVar->replaceAllUsesWith(NewGA); - // DGV will conflict with NewGA because they both had the same + // DGVar will conflict with NewGA because they both had the same // name. We must erase this now so ForceRenaming doesn't assert // because DGV might not have internal linkage. - DGV->eraseFromParent(); + DGVar->eraseFromParent(); // Proceed to 'common' steps } else - return Error(Err, "Global-Alias Collision on '" + - ToStr(SGA->getType(), Src) +"':%"+SGA->getName()+ - " - symbol multiple defined"); - } else if (Function *DF = Dest->getFunction(SGA->getName())) { - RecursiveResolveTypes(SGA->getType(), DF->getType(), - &Dest->getTypeSymbolTable(), ""); - + return Error(Err, "Global-Alias Collision on '" + SGA->getName() + + "': symbol multiple defined"); + } else if (Function *DF = dyn_cast_or_null(DGV)) { // The only allowed way is to link alias with external declaration. if (DF->isDeclaration()) { + // But only if aliasee is function too... + if (!isa(DAliasee)) + return Error(Err, "Function-Alias Collision on '" + SGA->getName() + + "': aliasee is not function"); + NewGA = new GlobalAlias(SGA->getType(), SGA->getLinkage(), SGA->getName(), DAliasee, Dest); CopyGVAttributes(NewGA, SGA); @@ -707,11 +810,11 @@ static bool LinkAlias(Module *Dest, const Module *Src, // Proceed to 'common' steps } else - return Error(Err, "Function-Alias Collision on '" + - ToStr(SGA->getType(), Src) +"':%"+SGA->getName()+ - " - symbol multiple defined"); + return Error(Err, "Function-Alias Collision on '" + SGA->getName() + + "': symbol multiple defined"); } else { - // Nothing similar found, just copy alias into destination module. + // No linking to be performed, simply create an identical version of the + // alias over in the dest module... NewGA = new GlobalAlias(SGA->getType(), SGA->getLinkage(), SGA->getName(), DAliasee, Dest); @@ -722,16 +825,15 @@ static bool LinkAlias(Module *Dest, const Module *Src, assert(NewGA && "No alias was created in destination module!"); - // If the symbol table renamed the function, but it is an externally - // visible symbol, DGV must be an existing function with internal - // linkage. Rename it. + // 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()) ForceRenaming(NewGA, SGA->getName()); // Remember this mapping so uses in the source module get remapped // later by RemapOperand. - ValueMap.insert(std::make_pair(SGA, NewGA)); + ValueMap[SGA] = NewGA; } return false; @@ -754,17 +856,19 @@ static bool LinkGlobalInits(Module *Dest, const Module *Src, Constant *SInit = cast(RemapOperand(SGV->getInitializer(), ValueMap)); - GlobalVariable *DGV = cast(ValueMap[SGV]); + GlobalVariable *DGV = + cast(ValueMap[SGV]->stripPointerCasts()); if (DGV->hasInitializer()) { if (SGV->hasExternalLinkage()) { if (DGV->getInitializer() != SInit) - return Error(Err, "Global Variable Collision on '" + - ToStr(SGV->getType(), Src) +"':%"+SGV->getName()+ - " - Global variables have different initializers"); - } else if (DGV->hasLinkOnceLinkage() || DGV->hasWeakLinkage()) { + 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()) { + } else if (SGV->hasLinkOnceLinkage() || SGV->hasWeakLinkage() || + SGV->hasCommonLinkage()) { // Nothing is required, mapped values will take the new global // automatically. } else if (DGV->hasAppendingLinkage()) { @@ -791,36 +895,66 @@ static bool LinkFunctionProtos(Module *Dest, const Module *Src, // 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 + Function *DF = 0; + Value *MappedDF; + + // 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 && SF->getType() != DF->getType()) - // If types don't agree because of opaque, try to resolve them - RecursiveResolveTypes(SF->getType(), DF->getType(), - &Dest->getTypeSymbolTable(), ""); + if (DF && DF->hasInternalLinkage()) + DF = 0; } - - // Check visibility - if (DF && !DF->hasInternalLinkage() && - SF->getVisibility() != DF->getVisibility()) { + + // If there is no linkage to be performed, just bring over SF without + // modifying it. + if (DF == 0) { + // Function does not already exist, simply insert an function signature + // identical to SF into the dest module. + Function *NewDF = Function::Create(SF->getFunctionType(), + SF->getLinkage(), + SF->getName(), Dest); + CopyGVAttributes(NewDF, SF); + + // 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()) + ForceRenaming(NewDF, SF->getName()); + + // ... and remember this mapping... + ValueMap[SF] = NewDF; + continue; + } + + + // 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!"); + + // Otherwise, replace the visibility of DF if DF is a prototype. + if (DF->isDeclaration()) + DF->setVisibility(SF->getVisibility()); } - if (DF && DF->hasInternalLinkage()) - DF = NULL; - - if (DF && DF->getType() != SF->getType()) { + 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 = new Function(SF->getFunctionType(), SF->getLinkage(), - SF->getName(), Dest); + 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 @@ -840,77 +974,77 @@ static bool LinkFunctionProtos(Module *Dest, const Module *Src, // 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()); + continue; } 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) + "'"); + // We have two functions of the same name but different type. Any use + // of the source must be mapped to the destination, with a cast. + MappedDF = ConstantExpr::getBitCast(DF, SF->getType()); } - } else if (!DF || SF->hasInternalLinkage() || DF->hasInternalLinkage()) { - // Function does not already exist, simply insert an function signature - // identical to SF into the dest module. - Function *NewDF = new Function(SF->getFunctionType(), SF->getLinkage(), - SF->getName(), Dest); - CopyGVAttributes(NewDF, SF); - - // 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->getName() != SF->getName() && !NewDF->hasInternalLinkage()) - ForceRenaming(NewDF, SF->getName()); - - // ... and remember this mapping... - ValueMap.insert(std::make_pair(SF, NewDF)); - } else if (SF->isDeclaration()) { + } else { + MappedDF = DF; + } + + 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.insert(std::make_pair(SF, DF)); + ValueMap[SF] = MappedDF; DF->setLinkage(SF->getLinkage()); - } + } } else { - ValueMap.insert(std::make_pair(SF, DF)); - } - } else if (DF->isDeclaration() && !DF->hasDLLImportLinkage()) { - // If DF is external but SF is not... - // Link the external functions, update linkage qualifiers - ValueMap.insert(std::make_pair(SF, DF)); + ValueMap[SF] = MappedDF; + } + 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, MappedDF)); DF->setLinkage(SF->getLinkage()); - // Visibility of prototype is overridden by vis of definition. - DF->setVisibility(SF->getVisibility()); - } else if (SF->hasWeakLinkage() || SF->hasLinkOnceLinkage()) { - // At this point we know that DF has LinkOnce, Weak, or External* linkage. - ValueMap.insert(std::make_pair(SF, DF)); + continue; + } + + // At this point we know that DF has LinkOnce, Weak, or External* linkage. + if (SF->hasWeakLinkage() || SF->hasLinkOnceLinkage() || + SF->hasCommonLinkage()) { + ValueMap[SF] = MappedDF; // Linkonce+Weak = Weak // *+External Weak = * - if ((DF->hasLinkOnceLinkage() && SF->hasWeakLinkage()) || + if ((DF->hasLinkOnceLinkage() && + (SF->hasWeakLinkage() || SF->hasCommonLinkage())) || DF->hasExternalWeakLinkage()) DF->setLinkage(SF->getLinkage()); - } else if (DF->hasWeakLinkage() || DF->hasLinkOnceLinkage()) { + continue; + } + + if (DF->hasWeakLinkage() || DF->hasLinkOnceLinkage() || + DF->hasCommonLinkage()) { // At this point we know that SF has LinkOnce or External* linkage. - ValueMap.insert(std::make_pair(SF, DF)); - if (!SF->hasLinkOnceLinkage() && !SF->hasExternalWeakLinkage()) - // Don't inherit linkonce & external weak linkage + ValueMap[SF] = MappedDF; + + // 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()); - } else if (SF->getLinkage() != DF->getLinkage()) { - return Error(Err, "Functions named '" + SF->getName() + - "' have different linkage specifiers!"); - } else if (SF->hasExternalLinkage()) { - // The function is defined identically in both modules!! + DF->deleteBody(); + } + continue; + } + + 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!"); - } else { - assert(0 && "Unknown linkage configuration found!"); - } + assert(0 && "Unknown linkage configuration found!"); } return false; } @@ -930,7 +1064,7 @@ static bool LinkFunctionBody(Function *Dest, Function *Src, DI->setName(I->getName()); // Copy the name information over... // Add a mapping to our local map - ValueMap.insert(std::make_pair(I, DI)); + ValueMap[I] = DI; } // Splice the body of the source function into the dest function. @@ -968,10 +1102,10 @@ static bool LinkFunctionBodies(Module *Dest, Module *Src, // 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(ValueMap[SF]); // Destination function + Function *DF = dyn_cast(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; @@ -1084,11 +1218,10 @@ static bool LinkAppendingVars(Module *M, static bool ResolveAliases(Module *Dest) { for (Module::alias_iterator I = Dest->alias_begin(), E = Dest->alias_end(); - I != E; ++I) { - GlobalValue* GV = const_cast(I->getAliasedGlobal()); - if (!GV->isDeclaration()) - I->replaceAllUsesWith(GV); - } + I != E; ++I) + if (const GlobalValue *GV = I->resolveAliasedGlobal()) + if (!GV->isDeclaration()) + I->replaceAllUsesWith(const_cast(GV)); return false; }