//
for (Module::const_giterator I = Src->gbegin(), E = Src->gend(); I != E; ++I){
const GlobalVariable *SGV = I;
- Value *V;
-
- // If the global variable has a name, and that name is already in use in the
- // Dest module, make sure that the name is a compatible global variable...
- //
- if (SGV->hasExternalLinkage() && SGV->hasName() &&
- (V = ST->lookup(SGV->getType(), SGV->getName())) &&
- cast<GlobalVariable>(V)->hasExternalLinkage()) {
- // The same named thing is a global variable, because the only two things
+ GlobalVariable *DGV = 0;
+ if (SGV->hasName()) {
+ // A same named thing is a global variable, because the only two things
// that may be in a module level symbol table are Global Vars and
// Functions, and they both have distinct, nonoverlapping, possible types.
//
- GlobalVariable *DGV = cast<GlobalVariable>(V);
+ DGV = cast_or_null<GlobalVariable>(ST->lookup(SGV->getType(),
+ SGV->getName()));
+ }
- // Check to see if the two GV's have the same Const'ness...
- if (SGV->isConstant() != DGV->isConstant())
- return Error(Err, "Global Variable Collision on '" +
- SGV->getType()->getDescription() + "':%" + SGV->getName() +
- " - Global variables differ in const'ness");
+ assert(SGV->hasInitializer() || SGV->hasExternalLinkage() &&
+ "Global must either be external or have an initializer!");
- // Okay, everything is cool, remember the mapping...
- ValueMap.insert(std::make_pair(SGV, DGV));
- } else {
+ bool SGExtern = SGV->isExternal();
+ bool DGExtern = DGV ? DGV->isExternal() : false;
+
+ if (!DGV || DGV->hasInternalLinkage() || SGV->hasInternalLinkage()) {
// 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...
//
- GlobalVariable *DGV =
- new GlobalVariable(SGV->getType()->getElementType(), SGV->isConstant(),
- SGV->hasInternalLinkage(), 0, SGV->getName());
-
- // Add the new global to the dest module
- Dest->getGlobalList().push_back(DGV);
+ GlobalVariable *NewDGV =
+ new GlobalVariable(SGV->getType()->getElementType(),
+ SGV->isConstant(), SGV->getLinkage(), /*init*/0,
+ SGV->getName(), Dest);
+
+ // 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()){
+ assert(DGV && DGV->getName() == SGV->getName() &&
+ DGV->hasInternalLinkage());
+ DGV->setName("");
+ NewDGV->setName(SGV->getName()); // Force the name back
+ DGV->setName(SGV->getName()); // This will cause a renaming
+ assert(NewDGV->getName() == SGV->getName() &&
+ DGV->getName() != SGV->getName());
+ }
// Make sure to remember this mapping...
+ ValueMap.insert(std::make_pair(SGV, NewDGV));
+ } else if (SGV->isExternal()) {
+ // If SGV is external or if both SGV & DGV are external.. Just link the
+ // external globals, we aren't adding anything.
ValueMap.insert(std::make_pair(SGV, DGV));
+
+ } else if (DGV->isExternal()) { // If DGV is external but SGV is not...
+ ValueMap.insert(std::make_pair(SGV, DGV));
+ DGV->setLinkage(SGV->getLinkage()); // Inherit linkage!
+ } else if (SGV->getLinkage() != DGV->getLinkage()) {
+ return Error(Err, "Global variables named '" + SGV->getName() +
+ "' have different linkage specifiers!");
+ } else if (SGV->hasExternalLinkage()) {
+ // Allow linking two exactly identical external global variables...
+ if (SGV->isConstant() != DGV->isConstant() ||
+ SGV->getInitializer() != DGV->getInitializer())
+ return Error(Err, "Global Variable Collision on '" +
+ SGV->getType()->getDescription() + " %" + SGV->getName() +
+ "' - Global variables differ in const'ness");
+ ValueMap.insert(std::make_pair(SGV, DGV));
+ } else if (SGV->hasLinkOnceLinkage()) {
+ // If the global variable has a name, and that name is already in use in
+ // the Dest module, make sure that the name is a compatible global
+ // variable...
+ //
+ // Check to see if the two GV's have the same Const'ness...
+ if (SGV->isConstant() != DGV->isConstant())
+ return Error(Err, "Global Variable Collision on '" +
+ SGV->getType()->getDescription() + " %" + SGV->getName() +
+ "' - Global variables differ in const'ness");
+
+ // Okay, everything is cool, remember the mapping...
+ ValueMap.insert(std::make_pair(SGV, DGV));
+ } else if (SGV->hasAppendingLinkage()) {
+ assert(0 && "FIXME: Appending linkage unimplemented!");
+ } else {
+ assert(0 && "Unknown linkage!");
}
}
return false;
if (SGV->hasInitializer()) { // Only process initialized GV's
// Figure out what the initializer looks like in the dest module...
- Constant *DInit =
+ Constant *SInit =
cast<Constant>(RemapOperand(SGV->getInitializer(), ValueMap, 0));
GlobalVariable *DGV = cast<GlobalVariable>(ValueMap[SGV]);
- if (DGV->hasInitializer() && SGV->hasExternalLinkage() &&
- DGV->hasExternalLinkage()) {
- if (DGV->getInitializer() != DInit)
- return Error(Err, "Global Variable Collision on '" +
- SGV->getType()->getDescription() + "':%" +SGV->getName()+
- " - Global variables have different initializers");
+ if (DGV->hasInitializer()) {
+ assert(SGV->getLinkage() == DGV->getLinkage());
+ if (SGV->hasExternalLinkage()) {
+ if (DGV->getInitializer() != SInit)
+ return Error(Err, "Global Variable Collision on '" +
+ SGV->getType()->getDescription() +"':%"+SGV->getName()+
+ " - Global variables have different initializers");
+ } else if (DGV->hasLinkOnceLinkage()) {
+ // Nothing is required, mapped values will take the new global
+ // automatically.
+ } else if (DGV->hasAppendingLinkage()) {
+ assert(0 && "Appending linkage unimplemented!");
+ } else {
+ assert(0 && "Unknown linkage!");
+ }
} else {
// Copy the initializer over now...
- DGV->setInitializer(DInit);
+ DGV->setInitializer(SInit);
}
}
}
//
for (Module::const_iterator I = Src->begin(), E = Src->end(); I != E; ++I) {
const Function *SF = I; // SrcFunction
- Value *V;
-
- // If the function has a name, and that name is already in use in the Dest
- // module, make sure that the name is a compatible function...
- //
- if (SF->hasExternalLinkage() && SF->hasName() &&
- (V = ST->lookup(SF->getType(), SF->getName())) &&
- cast<Function>(V)->hasExternalLinkage()) {
+ Function *DF = 0;
+ if (SF->hasName())
// The same named thing is a Function, because the only two things
// that may be in a module level symbol table are Global Vars and
// Functions, and they both have distinct, nonoverlapping, possible types.
//
- Function *DF = cast<Function>(V); // DestFunction
-
- // Check to make sure the function is not defined in both modules...
- if (!SF->isExternal() && !DF->isExternal())
- return Error(Err, "Function '" +
- SF->getFunctionType()->getDescription() + "':\"" +
- SF->getName() + "\" - Function is already defined!");
-
- // Otherwise, just remember this mapping...
- ValueMap.insert(std::make_pair(SF, DF));
- } else {
- // Function does not already exist, simply insert an external function
- // signature identical to SF into the dest module...
- Function *DF = new Function(SF->getFunctionType(),
- SF->hasInternalLinkage(),
- SF->getName());
-
- // Add the function signature to the dest module...
- Dest->getFunctionList().push_back(DF);
+ DF = cast_or_null<Function>(ST->lookup(SF->getType(), SF->getName()));
+
+ 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);
+
+ // 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()) {
+ assert(DF && DF->getName() == SF->getName() &&DF->hasInternalLinkage());
+ DF->setName("");
+ NewDF->setName(SF->getName()); // Force the name back
+ DF->setName(SF->getName()); // This will cause a renaming
+ assert(NewDF->getName() == SF->getName() &&
+ DF->getName() != SF->getName());
+ }
// ... and remember this mapping...
+ ValueMap.insert(std::make_pair(SF, NewDF));
+ } else if (SF->isExternal()) {
+ // If SF is external or if both SF & DF are external.. Just link the
+ // external functions, we aren't adding anything.
+ ValueMap.insert(std::make_pair(SF, DF));
+ } else if (DF->isExternal()) { // If DF is external but SF is not...
+ // Link the external functions, update linkage qualifiers
ValueMap.insert(std::make_pair(SF, DF));
+ 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 in both modules!!
+ return Error(Err, "Function '" +
+ SF->getFunctionType()->getDescription() + "':\"" +
+ SF->getName() + "\" - Function is already defined!");
+ } else if (SF->hasLinkOnceLinkage()) {
+ // Completely ignore the source function.
+ ValueMap.insert(std::make_pair(SF, DF));
+ } else {
+ assert(0 && "Unknown linkage configuration found!");
}
}
return false;
// DF not external SF external?
if (!DF->isExternal()) {
+ if (DF->hasLinkOnceLinkage()) continue; // No relinkage for link-once!
if (Err)
*Err = "Function '" + (SF->hasName() ? SF->getName() :std::string(""))
+ "' body multiply defined!";
// shouldn't be relied on to be consistent.
//
bool LinkModules(Module *Dest, const Module *Src, std::string *ErrorMsg) {
+ if (Dest->getEndianness() != Src->getEndianness())
+ std::cerr << "WARNING: Linking two modules of different endianness!\n";
+ if (Dest->getPointerSize() != Src->getPointerSize())
+ std::cerr << "WARNING: Linking two modules of different pointer size!\n";
// LinkTypes - Go through the symbol table of the Src module and see if any
// types are named in the src module that are not named in the Dst module.
projects / oota-llvm.git / blobdiff