Add new linkage types to support a real frontend
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5786 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/Linker.cpp b/lib/Transforms/Utils/Linker.cpp
index 60c6e03..b5207a8 100644
--- a/lib/Transforms/Utils/Linker.cpp
+++ b/lib/Transforms/Utils/Linker.cpp
@@ -189,42 +189,48 @@
//
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()));
+ }
+ assert(SGV->hasInitializer() || SGV->hasExternalLinkage() &&
+ "Global must either be external or have an initializer!");
+
+ 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);
+
+ // Make sure to remember this mapping...
+ ValueMap.insert(std::make_pair(SGV, DGV));
+ } 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()) {
+ // 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 {
- // 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);
-
- // Make sure to remember this mapping...
- ValueMap.insert(std::make_pair(SGV, DGV));
+ assert(0 && "Unknown linkage!");
}
}
return false;
@@ -245,19 +251,28 @@
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);
}
}
}
@@ -278,39 +293,42 @@
//
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
+ 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 external function
+ // signature identical to SF into the dest module...
+ Function *DF = new Function(SF->getFunctionType(), SF->getLinkage(),
+ SF->getName(), Dest);
+
+ // ... and remember this mapping...
+ ValueMap.insert(std::make_pair(SF, DF));
+ } 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 {
- // 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);
-
- // ... and remember this mapping...
+ } else if (SF->getLinkage() == GlobalValue::LinkOnceLinkage) {
+ // Completely ignore the source function.
ValueMap.insert(std::make_pair(SF, DF));
}
}
@@ -391,6 +409,7 @@
// 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!";