+Constant *Module::getOrInsertFunction(const std::string &Name,
+ const FunctionType *Ty,
+ AttrListPtr AttributeList) {
+ ValueSymbolTable &SymTab = getValueSymbolTable();
+
+ // See if we have a definition for the specified function already.
+ GlobalValue *F = dyn_cast_or_null<GlobalValue>(SymTab.lookup(Name));
+ if (F == 0) {
+ // Nope, add it
+ Function *New = Function::Create(Ty, GlobalVariable::ExternalLinkage, Name);
+ if (!New->isIntrinsic()) // Intrinsics get attrs set on construction
+ New->setAttributes(AttributeList);
+ FunctionList.push_back(New);
+ return New; // Return the new prototype.
+ }
+
+ // Okay, the function exists. Does it have externally visible linkage?
+ if (F->hasLocalLinkage()) {
+ // Clear the function's name.
+ F->setName("");
+ // Retry, now there won't be a conflict.
+ Constant *NewF = getOrInsertFunction(Name, Ty);
+ F->setName(&Name[0], Name.size());
+ return NewF;
+ }
+
+ // If the function exists but has the wrong type, return a bitcast to the
+ // right type.
+ if (F->getType() != PointerType::getUnqual(Ty))
+ return ConstantExpr::getBitCast(F, PointerType::getUnqual(Ty));
+
+ // Otherwise, we just found the existing function or a prototype.
+ return F;
+}