/// SplitFunctionsOutOfModule - Given a module and a list of functions in the
/// module, split the functions OUT of the specified module, and place them in
/// the new module.
Module *
llvm::SplitFunctionsOutOfModule(Module *M,
const std::vector<Function*> &F,
ValueToValueMapTy &VMap) {
// Make sure functions & globals are all external so that linkage
// between the two modules will work.
for (Module::iterator I = M->begin(), E = M->end(); I != E; ++I)
I->setLinkage(GlobalValue::ExternalLinkage);
for (Module::global_iterator I = M->global_begin(), E = M->global_end();
I != E; ++I) {
if (I->hasName() && I->getName()[0] == '\01')
I->setName(I->getName().substr(1));
I->setLinkage(GlobalValue::ExternalLinkage);
}
ValueToValueMapTy NewVMap;
Module *New = CloneModule(M, NewVMap);
// Remove the Test functions from the Safe module
std::set<Function *> TestFunctions;
for (unsigned i = 0, e = F.size(); i != e; ++i) {
Function *TNOF = cast<Function>(VMap[F[i]]);
DEBUG(errs() << "Removing function ");
DEBUG(TNOF->printAsOperand(errs(), false));
DEBUG(errs() << "\n");
TestFunctions.insert(cast<Function>(NewVMap[TNOF]));
DeleteFunctionBody(TNOF); // Function is now external in this module!
}
// Remove the Safe functions from the Test module
for (Module::iterator I = New->begin(), E = New->end(); I != E; ++I)
if (!TestFunctions.count(I))
DeleteFunctionBody(I);
// Try to split the global initializers evenly
for (Module::global_iterator I = M->global_begin(), E = M->global_end();
I != E; ++I) {
GlobalVariable *GV = cast<GlobalVariable>(NewVMap[I]);
if (Function *TestFn = globalInitUsesExternalBA(I)) {
if (Function *SafeFn = globalInitUsesExternalBA(GV)) {
errs() << "*** Error: when reducing functions, encountered "
"the global '";
GV->printAsOperand(errs(), false);
errs() << "' with an initializer that references blockaddresses "
"from safe function '" << SafeFn->getName()
<< "' and from test function '" << TestFn->getName() << "'.\n";
exit(1);
}
I->setInitializer(nullptr); // Delete the initializer to make it external
} else {
// If we keep it in the safe module, then delete it in the test module
GV->setInitializer(nullptr);
}
}
// Make sure that there is a global ctor/dtor array in both halves of the
// module if they both have static ctor/dtor functions.
SplitStaticCtorDtor("llvm.global_ctors", M, New, NewVMap);
SplitStaticCtorDtor("llvm.global_dtors", M, New, NewVMap);
return New;
}
