+ RF_None, &TypeMap, &ValMaterializer));
+ }
+}
+
+/// linkModuleFlagsMetadata - Merge the linker flags in Src into the Dest
+/// module.
+bool ModuleLinker::linkModuleFlagsMetadata() {
+ // If the source module has no module flags, we are done.
+ const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
+ if (!SrcModFlags) return false;
+
+ // If the destination module doesn't have module flags yet, then just copy
+ // over the source module's flags.
+ NamedMDNode *DstModFlags = DstM->getOrInsertModuleFlagsMetadata();
+ if (DstModFlags->getNumOperands() == 0) {
+ for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
+ DstModFlags->addOperand(SrcModFlags->getOperand(I));
+
+ return false;
+ }
+
+ // First build a map of the existing module flags and requirements.
+ DenseMap<MDString*, MDNode*> Flags;
+ SmallSetVector<MDNode*, 16> Requirements;
+ for (unsigned I = 0, E = DstModFlags->getNumOperands(); I != E; ++I) {
+ MDNode *Op = DstModFlags->getOperand(I);
+ ConstantInt *Behavior = cast<ConstantInt>(Op->getOperand(0));
+ MDString *ID = cast<MDString>(Op->getOperand(1));
+
+ if (Behavior->getZExtValue() == Module::Require) {
+ Requirements.insert(cast<MDNode>(Op->getOperand(2)));
+ } else {
+ Flags[ID] = Op;
+ }
+ }
+
+ // Merge in the flags from the source module, and also collect its set of
+ // requirements.
+ bool HasErr = false;
+ for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I) {
+ MDNode *SrcOp = SrcModFlags->getOperand(I);
+ ConstantInt *SrcBehavior = cast<ConstantInt>(SrcOp->getOperand(0));
+ MDString *ID = cast<MDString>(SrcOp->getOperand(1));
+ MDNode *DstOp = Flags.lookup(ID);
+ unsigned SrcBehaviorValue = SrcBehavior->getZExtValue();
+
+ // If this is a requirement, add it and continue.
+ if (SrcBehaviorValue == Module::Require) {
+ // If the destination module does not already have this requirement, add
+ // it.
+ if (Requirements.insert(cast<MDNode>(SrcOp->getOperand(2)))) {
+ DstModFlags->addOperand(SrcOp);
+ }
+ continue;
+ }
+
+ // If there is no existing flag with this ID, just add it.
+ if (!DstOp) {
+ Flags[ID] = SrcOp;
+ DstModFlags->addOperand(SrcOp);
+ continue;
+ }
+
+ // Otherwise, perform a merge.
+ ConstantInt *DstBehavior = cast<ConstantInt>(DstOp->getOperand(0));
+ unsigned DstBehaviorValue = DstBehavior->getZExtValue();
+
+ // If either flag has override behavior, handle it first.
+ if (DstBehaviorValue == Module::Override) {
+ // Diagnose inconsistent flags which both have override behavior.
+ if (SrcBehaviorValue == Module::Override &&
+ SrcOp->getOperand(2) != DstOp->getOperand(2)) {
+ HasErr |= emitError("linking module flags '" + ID->getString() +
+ "': IDs have conflicting override values");
+ }
+ continue;
+ } else if (SrcBehaviorValue == Module::Override) {
+ // Update the destination flag to that of the source.
+ DstOp->replaceOperandWith(0, SrcBehavior);
+ DstOp->replaceOperandWith(2, SrcOp->getOperand(2));
+ continue;
+ }
+
+ // Diagnose inconsistent merge behavior types.
+ if (SrcBehaviorValue != DstBehaviorValue) {
+ HasErr |= emitError("linking module flags '" + ID->getString() +
+ "': IDs have conflicting behaviors");
+ continue;
+ }
+
+ // Perform the merge for standard behavior types.
+ switch (SrcBehaviorValue) {
+ case Module::Require:
+ case Module::Override: assert(0 && "not possible"); break;
+ case Module::Error: {
+ // Emit an error if the values differ.
+ if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
+ HasErr |= emitError("linking module flags '" + ID->getString() +
+ "': IDs have conflicting values");
+ }
+ continue;
+ }
+ case Module::Warning: {
+ // Emit a warning if the values differ.
+ if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
+ if (!SuppressWarnings) {
+ errs() << "WARNING: linking module flags '" << ID->getString()
+ << "': IDs have conflicting values";
+ }
+ }
+ continue;
+ }
+ case Module::Append: {
+ MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
+ MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
+ unsigned NumOps = DstValue->getNumOperands() + SrcValue->getNumOperands();
+ Value **VP, **Values = VP = new Value*[NumOps];
+ for (unsigned i = 0, e = DstValue->getNumOperands(); i != e; ++i, ++VP)
+ *VP = DstValue->getOperand(i);
+ for (unsigned i = 0, e = SrcValue->getNumOperands(); i != e; ++i, ++VP)
+ *VP = SrcValue->getOperand(i);
+ DstOp->replaceOperandWith(2, MDNode::get(DstM->getContext(),
+ ArrayRef<Value*>(Values,
+ NumOps)));
+ delete[] Values;
+ break;
+ }
+ case Module::AppendUnique: {
+ SmallSetVector<Value*, 16> Elts;
+ MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
+ MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
+ for (unsigned i = 0, e = DstValue->getNumOperands(); i != e; ++i)
+ Elts.insert(DstValue->getOperand(i));
+ for (unsigned i = 0, e = SrcValue->getNumOperands(); i != e; ++i)
+ Elts.insert(SrcValue->getOperand(i));
+ DstOp->replaceOperandWith(2, MDNode::get(DstM->getContext(),
+ ArrayRef<Value*>(Elts.begin(),
+ Elts.end())));
+ break;
+ }
+ }
+ }
+
+ // Check all of the requirements.
+ for (unsigned I = 0, E = Requirements.size(); I != E; ++I) {
+ MDNode *Requirement = Requirements[I];
+ MDString *Flag = cast<MDString>(Requirement->getOperand(0));
+ Value *ReqValue = Requirement->getOperand(1);
+
+ MDNode *Op = Flags[Flag];
+ if (!Op || Op->getOperand(2) != ReqValue) {
+ HasErr |= emitError("linking module flags '" + Flag->getString() +
+ "': does not have the required value");
+ continue;
+ }