X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FLinker%2FLinkModules.cpp;h=47aa5484e76ad7e9f691b681ccf8ebed304bbb3b;hb=8f77daef04355c00b78b645f5aae5694e7a8b631;hp=b5207a8542926b01b5b3fe63b375d898834b938a;hpb=4ad02e726d9b634372b037d4b352d8b63bb9e849;p=oota-llvm.git diff --git a/lib/Linker/LinkModules.cpp b/lib/Linker/LinkModules.cpp index b5207a85429..47aa5484e76 100644 --- a/lib/Linker/LinkModules.cpp +++ b/lib/Linker/LinkModules.cpp @@ -202,22 +202,54 @@ static bool LinkGlobals(Module *Dest, const Module *Src, assert(SGV->hasInitializer() || SGV->hasExternalLinkage() && "Global must either be external or have an initializer!"); + 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... // - DGV = new GlobalVariable(SGV->getType()->getElementType(), - SGV->isConstant(), SGV->getLinkage(), /*init*/0, - SGV->getName(), Dest); + 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() || SGV->hasLinkOnceLinkage() || - SGV->hasAppendingLinkage()) { + } 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... @@ -225,10 +257,13 @@ static bool LinkGlobals(Module *Dest, const Module *Src, // 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"); + 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!"); } @@ -302,34 +337,47 @@ static bool LinkFunctionProtos(Module *Dest, const Module *Src, DF = cast_or_null(ST->lookup(SF->getType(), SF->getName())); if (!DF || SF->hasInternalLinkage() || DF->hasInternalLinkage()) { - // 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->getLinkage(), - SF->getName(), Dest); + // 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->getLinkage() == GlobalValue::AppendingLinkage) { - return Error(Err, "Functions named '" + SF->getName() + - "' have appending linkage!"); - } else if (SF->getLinkage() == GlobalValue::ExternalLinkage) { - // 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... - // - // 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 if (SF->getLinkage() == GlobalValue::LinkOnceLinkage) { + } 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; @@ -431,6 +479,10 @@ static bool LinkFunctionBodies(Module *Dest, const Module *Src, // 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.