+
+ Function* globalInitUsesExternalBA(GlobalVariable* GV) {
+ if (!GV->hasInitializer())
+ return 0;
+
+ Constant *I = GV->getInitializer();
+
+ // walk the values used by the initializer
+ // (and recurse into things like ConstantExpr)
+ std::vector<Constant*> Todo;
+ std::set<Constant*> Done;
+ Todo.push_back(I);
+
+ while (!Todo.empty()) {
+ Constant* V = Todo.back();
+ Todo.pop_back();
+ Done.insert(V);
+
+ if (BlockAddress *BA = dyn_cast<BlockAddress>(V)) {
+ Function *F = BA->getFunction();
+ if (F->isDeclaration())
+ return F;
+ }
+
+ for (User::op_iterator i = V->op_begin(), e = V->op_end(); i != e; ++i) {
+ Constant *C = dyn_cast<Constant>(*i);
+ if (C && !isa<GlobalValue>(C) && !Done.count(C))
+ Todo.push_back(C);
+ }
+ }
+ return 0;
+ }
+} // end anonymous namespace